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* [Patch v2 00/28] UEFI variable protection
@ 2022-04-29 18:04 Judah Vang
  2022-04-29 18:04 ` [Patch v2 01/28] MdeModulePkg: Add new GUID for Variable Store Info Judah Vang
                   ` (29 more replies)
  0 siblings, 30 replies; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel

For a more detail description of the UEFI variable protected feature you can
view the Readme.md located at the following location:
https://github.com/judahvang/edk2/tree/rpmc-update


Judah Vang (28):
  MdeModulePkg: Add new GUID for Variable Store Info
  SecurityPkg: Add new GUIDs for
  MdeModulePkg: Update AUTH_VARIABLE_INFO struct
  MdeModulePkg: Add reference to new Ppi Guid
  MdeModulePkg: Add new ProtectedVariable GUIDs
  MdeModulePkg: Add new include files
  MdeModulePkg: Add Null ProtectedVariable Library
  MdeModulePkg: Add new Variable functionality
  MdeModulePkg: Add support for Protected Variables
  SecurityPkg: Add new KeyService types and defines
  SecurityPkg: Update RPMC APIs with index
  SecurityPkg: Add new variable types and functions
  SecurityPkg: Fix GetVariableKey API
  SecurityPkg: Add null encryption variable libs
  SecurityPkg: Add VariableKey library function
  SecurityPkg: Add EncryptionVariable lib with AES
  SecurityPkg: Add Protected Variable Services
  MdeModulePkg: Reference Null ProtectedVariableLib
  SecurityPkg: Add references to new *.inf files
  ArmVirtPkg: Add reference to ProtectedVariableNull
  UefiPayloadPkg: Add ProtectedVariable reference
  EmulatorPkg: Add ProtectedVariable reference
  OvmfPkg: Add ProtectedVariable reference
  OvmfPkg: Add ProtectedVariableLib reference
  OvmfPkg: Add ProtectedVariableLib reference
  OvmfPkg: Add ProtectedVariableLib reference
  OvmfPkg: Add ProtectedVariable reference
  CryptoPkg: Enable cypto HMAC KDF library

 MdeModulePkg/MdeModulePkg.dec                                               |   13 +-
 SecurityPkg/SecurityPkg.dec                                                 |   43 +-
 ArmVirtPkg/ArmVirtQemu.dsc                                                  |    3 +-
 EmulatorPkg/EmulatorPkg.dsc                                                 |    3 +-
 MdeModulePkg/MdeModulePkg.dsc                                               |    4 +-
 OvmfPkg/AmdSev/AmdSevX64.dsc                                                |    3 +-
 OvmfPkg/Bhyve/BhyveX64.dsc                                                  |    3 +-
 OvmfPkg/CloudHv/CloudHvX64.dsc                                              |    1 +
 OvmfPkg/Microvm/MicrovmX64.dsc                                              |    3 +-
 OvmfPkg/OvmfPkgIa32.dsc                                                     |    1 +
 OvmfPkg/OvmfPkgIa32X64.dsc                                                  |    1 +
 OvmfPkg/OvmfPkgX64.dsc                                                      |    1 +
 OvmfPkg/OvmfXen.dsc                                                         |    3 +-
 SecurityPkg/SecurityPkg.dsc                                                 |   13 +-
 UefiPayloadPkg/UefiPayloadPkg.dsc                                           |    2 +
 CryptoPkg/Library/BaseCryptLib/SmmCryptLib.inf                              |    2 +-
 MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf  |   34 +
 MdeModulePkg/Universal/Variable/Pei/VariablePei.inf                         |   10 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf           |    3 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf                  |    3 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.inf        |    4 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf         |    3 +-
 SecurityPkg/Library/EncryptionVariableLib/EncryptionVariableLib.inf         |   43 +
 SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf |   38 +
 SecurityPkg/Library/ProtectedVariableLib/DxeProtectedVariableLib.inf        |   64 +
 SecurityPkg/Library/ProtectedVariableLib/PeiProtectedVariableLib.inf        |   68 +
 SecurityPkg/Library/ProtectedVariableLib/SmmProtectedVariableLib.inf        |   67 +
 SecurityPkg/Library/ProtectedVariableLib/SmmRuntimeProtectedVariableLib.inf |   62 +
 SecurityPkg/Library/VariableKeyLib/VariableKeyLib.inf                       |   36 +
 MdeModulePkg/Include/Guid/ProtectedVariable.h                               |   22 +
 MdeModulePkg/Include/Library/AuthVariableLib.h                              |    4 +-
 MdeModulePkg/Include/Library/EncryptionVariableLib.h                        |  165 ++
 MdeModulePkg/Include/Library/ProtectedVariableLib.h                         |  700 +++++++
 MdeModulePkg/Universal/Variable/Pei/Variable.h                              |   80 +-
 MdeModulePkg/Universal/Variable/Pei/VariableParsing.h                       |  309 +++
 MdeModulePkg/Universal/Variable/Pei/VariableStore.h                         |  116 ++
 MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h                       |  126 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.h                |   91 +-
 MdePkg/Include/Ppi/ReadOnlyVariable2.h                                      |    4 +-
 SecurityPkg/Include/Library/RpmcLib.h                                       |   15 +-
 SecurityPkg/Include/Library/VariableKeyLib.h                                |   37 +-
 SecurityPkg/Include/Ppi/KeyServicePpi.h                                     |   57 +
 SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.h              |   49 +
 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableInternal.h        |  611 ++++++
 MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariable.c           |  449 ++++
 MdeModulePkg/Universal/Variable/Pei/Variable.c                              |  886 ++------
 MdeModulePkg/Universal/Variable/Pei/VariableParsing.c                       |  941 +++++++++
 MdeModulePkg/Universal/Variable/Pei/VariableStore.c                         |  305 +++
 MdeModulePkg/Universal/Variable/RuntimeDxe/Reclaim.c                        |  349 +++-
 MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c                       | 2139 +++++++++++---------
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableDxe.c                    |   26 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableExLib.c                  |  167 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableNonVolatile.c            |  194 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.c                |  320 ++-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeCache.c           |    2 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c                    |   39 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.c          |   41 +-
 SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.c              |  728 +++++++
 SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariable.c          |  107 +
 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableCommon.c          | 2095 +++++++++++++++++++
 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableDxe.c             |  163 ++
 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariablePei.c             | 1331 ++++++++++++
 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmm.c             |  209 ++
 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmDxeCommon.c    |  975 +++++++++
 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmRuntime.c      |  233 +++
 SecurityPkg/Library/RpmcLibNull/RpmcLibNull.c                               |    8 +-
 SecurityPkg/Library/VariableKeyLib/VariableKeyLib.c                         |   59 +
 SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.c                 |    6 +-
 SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.uni |   16 +
 69 files changed, 12845 insertions(+), 1863 deletions(-)
 create mode 100644 MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
 create mode 100644 SecurityPkg/Library/EncryptionVariableLib/EncryptionVariableLib.inf
 create mode 100644 SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf
 create mode 100644 SecurityPkg/Library/ProtectedVariableLib/DxeProtectedVariableLib.inf
 create mode 100644 SecurityPkg/Library/ProtectedVariableLib/PeiProtectedVariableLib.inf
 create mode 100644 SecurityPkg/Library/ProtectedVariableLib/SmmProtectedVariableLib.inf
 create mode 100644 SecurityPkg/Library/ProtectedVariableLib/SmmRuntimeProtectedVariableLib.inf
 create mode 100644 SecurityPkg/Library/VariableKeyLib/VariableKeyLib.inf
 create mode 100644 MdeModulePkg/Include/Guid/ProtectedVariable.h
 create mode 100644 MdeModulePkg/Include/Library/EncryptionVariableLib.h
 create mode 100644 MdeModulePkg/Include/Library/ProtectedVariableLib.h
 create mode 100644 MdeModulePkg/Universal/Variable/Pei/VariableParsing.h
 create mode 100644 MdeModulePkg/Universal/Variable/Pei/VariableStore.h
 create mode 100644 SecurityPkg/Include/Ppi/KeyServicePpi.h
 create mode 100644 SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.h
 create mode 100644 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableInternal.h
 create mode 100644 MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariable.c
 create mode 100644 MdeModulePkg/Universal/Variable/Pei/VariableParsing.c
 create mode 100644 MdeModulePkg/Universal/Variable/Pei/VariableStore.c
 create mode 100644 SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.c
 create mode 100644 SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariable.c
 create mode 100644 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableCommon.c
 create mode 100644 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableDxe.c
 create mode 100644 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariablePei.c
 create mode 100644 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmm.c
 create mode 100644 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmDxeCommon.c
 create mode 100644 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmRuntime.c
 create mode 100644 SecurityPkg/Library/VariableKeyLib/VariableKeyLib.c
 create mode 100644 SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.uni

-- 
2.35.1.windows.2


^ permalink raw reply	[flat|nested] 49+ messages in thread

* [Patch v2 01/28] MdeModulePkg: Add new GUID for Variable Store Info
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-12  9:32   ` Wang, Jian J
  2022-04-29 18:04 ` [Patch v2 02/28] SecurityPkg: Add new GUIDs for Judah Vang
                   ` (28 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Liming Gao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Discover if Variable Store Info HOB has been published
by platform driver. It contains information in regards
to HOB or NV Variable Store availability

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 MdeModulePkg/MdeModulePkg.dec | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/MdeModulePkg/MdeModulePkg.dec b/MdeModulePkg/MdeModulePkg.dec
index cf79292ec877..f39827e4eacd 100644
--- a/MdeModulePkg/MdeModulePkg.dec
+++ b/MdeModulePkg/MdeModulePkg.dec
@@ -4,7 +4,7 @@
 # and libraries instances, which are used for those modules.
 #
 # Copyright (c) 2019, NVIDIA CORPORATION. All rights reserved.
-# Copyright (c) 2007 - 2021, Intel Corporation. All rights reserved.<BR>
+# Copyright (c) 2007 - 2022, Intel Corporation. All rights reserved.<BR>
 # Copyright (c) 2016, Linaro Ltd. All rights reserved.<BR>
 # (C) Copyright 2016 - 2019 Hewlett Packard Enterprise Development LP<BR>
 # Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR>
@@ -93,6 +93,14 @@ [LibraryClasses]
   #
   TpmMeasurementLib|Include/Library/TpmMeasurementLib.h
 
+  ## @libraryclass  Provides interfaces to encrypt/decrypt variable.
+  #
+  EncryptionVariableLib|Include/Library/EncryptionVariableLib.h
+
+  ## @libraryclass  Provides interfaces to encrypt/decrypt variable.
+  #
+  ProtectedVariableLib|Include/Library/ProtectedVariableLib.h
+
   ## @libraryclass  Provides authenticated variable services.
   #
   AuthVariableLib|Include/Library/AuthVariableLib.h
@@ -505,6 +513,9 @@ [Ppis]
   gEdkiiPeiCapsuleOnDiskPpiGuid             = { 0x71a9ea61, 0x5a35, 0x4a5d, { 0xac, 0xef, 0x9c, 0xf8, 0x6d, 0x6d, 0x67, 0xe0 } }
   gEdkiiPeiBootInCapsuleOnDiskModePpiGuid   = { 0xb08a11e4, 0xe2b7, 0x4b75, { 0xb5, 0x15, 0xaf, 0x61, 0x6, 0x68, 0xbf, 0xd1  } }
 
+  ## Include/Ppi/ReadOnlyVariable2.h
+  gEfiPeiVariableStoreDiscoveredPpiGuid     = { 0xa2fc038d, 0xfdf5, 0x4501, { 0xaf, 0x8e, 0x69, 0xb0, 0x20, 0xec, 0xe6, 0x63 } }
+
 [Protocols]
   ## Load File protocol provides capability to load and unload EFI image into memory and execute it.
   #  Include/Protocol/LoadPe32Image.h
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 02/28] SecurityPkg: Add new GUIDs for
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
  2022-04-29 18:04 ` [Patch v2 01/28] MdeModulePkg: Add new GUID for Variable Store Info Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-12  9:33   ` Wang, Jian J
  2022-04-29 18:04 ` [Patch v2 03/28] MdeModulePkg: Update AUTH_VARIABLE_INFO struct Judah Vang
                   ` (27 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Jiewen Yao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

The gEdkiiProtectedVariableGlobalGuid HOB contains the global
configuration data structure which is verified in PEI Phase.
The gEdkiiMetaDataHmacVariableGuid is used for saving the
meta data HMAC variable.
The gEdkiiProtectedVariableContextGuid contains the Protected
Variable context saved in PEI phase to be used later.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 SecurityPkg/SecurityPkg.dec | 43 +++++++++++++++++++-
 1 file changed, 42 insertions(+), 1 deletion(-)

diff --git a/SecurityPkg/SecurityPkg.dec b/SecurityPkg/SecurityPkg.dec
index 9f7a032d60d5..ea88908ea7d2 100644
--- a/SecurityPkg/SecurityPkg.dec
+++ b/SecurityPkg/SecurityPkg.dec
@@ -5,7 +5,7 @@
 #  It also provides the definitions(including PPIs/PROTOCOLs/GUIDs and library classes)
 #  and libraries instances, which are used for those features.
 #
-# Copyright (c) 2009 - 2020, Intel Corporation. All rights reserved.<BR>
+# Copyright (c) 2009 - 2022, Intel Corporation. All rights reserved.<BR>
 # (C) Copyright 2015 Hewlett Packard Enterprise Development LP <BR>
 # Copyright (c) Microsoft Corporation.<BR>
 # SPDX-License-Identifier: BSD-2-Clause-Patent
@@ -217,6 +217,18 @@ [Guids]
   ## GUID used to specify section with default dbt content
   gDefaultdbtFileGuid                = { 0x36c513ee, 0xa338, 0x4976, { 0xa0, 0xfb, 0x6d, 0xdb, 0xa3, 0xda, 0xfe, 0x87 } }
 
+  ## Include/Guid/ProtectedVariable.h
+  # {8EBF379A-F18E-4728-A410-00CF9A65BE91}
+  gEdkiiProtectedVariableGlobalGuid = { 0x8ebf379a, 0xf18e, 0x4728, { 0xa4, 0x10, 0x0, 0xcf, 0x9a, 0x65, 0xbe, 0x91 } }
+
+  ## Include/Guid/ProtectedVariable.h
+  # {e3e890ad-5b67-466e-904f-94ca7e9376bb}
+  gEdkiiMetaDataHmacVariableGuid = {0xe3e890ad, 0x5b67, 0x466e, {0x90, 0x4f, 0x94, 0xca, 0x7e, 0x93, 0x76, 0xbb}}
+
+  ## Include/Guid/ProtectedVariable.h
+  # {a11a3652-875b-495a-b097-200917580b98}
+  gEdkiiProtectedVariableContextGuid = {0xa11a3652, 0x875b, 0x495a, {0xb0, 0x97, 0x20, 0x09, 0x17, 0x58, 0x0b, 0x98} }
+
 [Ppis]
   ## The PPI GUID for that TPM physical presence should be locked.
   # Include/Ppi/LockPhysicalPresence.h
@@ -242,6 +254,10 @@ [Ppis]
   ## Include/Ppi/Tcg.h
   gEdkiiTcgPpiGuid = {0x57a13b87, 0x133d, 0x4bf3, { 0xbf, 0xf1, 0x1b, 0xca, 0xc7, 0x17, 0x6c, 0xf1 } }
 
+  ## Key Service Ppi
+  # Include/Ppi/KeyServicePpi.h
+  gKeyServicePpiGuid = {0x583592f6, 0xEC34, 0x4CED, {0x8E, 0x81, 0xC8, 0xD1, 0x36, 0x93, 0x04, 0x27}}
+
 #
 # [Error.gEfiSecurityPkgTokenSpaceGuid]
 #   0x80000001 | Invalid value provided.
@@ -325,6 +341,31 @@ [PcdsFixedAtBuild, PcdsPatchableInModule]
 
   gEfiSecurityPkgTokenSpaceGuid.PcdCpuRngSupportedAlgorithm|{0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00}|VOID*|0x00010032
 
+  ## Progress Code for variable integrity check result.<BR><BR>
+  #  DEFAULT: (EFI_PERIPHERAL_FIXED_MEDIA | [EFI_STATUS&0xFF])
+  # @Prompt Status Code for variable integiry check result
+  gEfiSecurityPkgTokenSpaceGuid.PcdStatusCodeVariableIntegrity|0x01070000|UINT32|0x00010033
+
+  ## Null-terminated Unicode string of the Platform Variable Name
+  # @Prompt known unprotected variable name
+  gEfiSecurityPkgTokenSpaceGuid.PcdPlatformVariableName|L""|VOID*|0x00010034
+
+  ## Guid name to identify Platform Variable Guid
+  # @Prompt known unprotected variable guid
+  gEfiSecurityPkgTokenSpaceGuid.PcdPlatformVariableGuid|{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }|VOID*|0x00010035
+
+  ## Defines Protected Variable Integrity support.
+  #   TRUE  - Enable Protected Variable Integrity.<BR>
+  #   FALSE - Disable Protected Variable Integrity.<BR>
+  # @Prompt Protected Variable Integrity support.
+  gEfiSecurityPkgTokenSpaceGuid.PcdProtectedVariableIntegrity|FALSE|BOOLEAN|0x00010036
+
+  ## Defines Protected Variable Confidentiality support.
+  #   TRUE  - Enable Protected Variable Confidentiality.<BR>
+  #   FALSE - Disable Protected Variable Confidentiality.<BR>
+  # @Prompt Protected Variable Integrity support.
+  gEfiSecurityPkgTokenSpaceGuid.PcdProtectedVariableConfidentiality|FALSE|BOOLEAN|0x00010037
+
 [PcdsFixedAtBuild, PcdsPatchableInModule, PcdsDynamic, PcdsDynamicEx]
   ## Image verification policy for OptionRom. Only following values are valid:<BR><BR>
   #  NOTE: Do NOT use 0x5 and 0x2 since it violates the UEFI specification and has been removed.<BR>
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 03/28] MdeModulePkg: Update AUTH_VARIABLE_INFO struct
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
  2022-04-29 18:04 ` [Patch v2 01/28] MdeModulePkg: Add new GUID for Variable Store Info Judah Vang
  2022-04-29 18:04 ` [Patch v2 02/28] SecurityPkg: Add new GUIDs for Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-12  9:33   ` Wang, Jian J
  2022-04-29 18:04 ` [Patch v2 04/28] MdeModulePkg: Add reference to new Ppi Guid Judah Vang
                   ` (26 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Liming Gao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Added NameSize and State to AUTH_VARIABLE_INFO struct.
The size of the name and state is needed when creating
the variable digest.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 MdeModulePkg/Include/Library/AuthVariableLib.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/MdeModulePkg/Include/Library/AuthVariableLib.h b/MdeModulePkg/Include/Library/AuthVariableLib.h
index 37aceba699e6..32391bbf2b61 100644
--- a/MdeModulePkg/Include/Library/AuthVariableLib.h
+++ b/MdeModulePkg/Include/Library/AuthVariableLib.h
@@ -1,7 +1,7 @@
 /** @file
   Provides services to initialize and process authenticated variables.
 
-Copyright (c) 2015 - 2017, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2015 - 2022, Intel Corporation. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
@@ -25,9 +25,11 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
                                        (OFFSET_OF (WIN_CERTIFICATE_UEFI_GUID, CertData)))
 
 typedef struct {
+  UINTN       NameSize;
   CHAR16      *VariableName;
   EFI_GUID    *VendorGuid;
   UINT32      Attributes;
+  UINT8       State;
   UINTN       DataSize;
   VOID        *Data;
   UINT32      PubKeyIndex;
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 04/28] MdeModulePkg: Add reference to new Ppi Guid
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (2 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 03/28] MdeModulePkg: Update AUTH_VARIABLE_INFO struct Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-12  9:32   ` Wang, Jian J
  2022-04-29 18:04 ` [Patch v2 05/28] MdeModulePkg: Add new ProtectedVariable GUIDs Judah Vang
                   ` (25 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Liming Gao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add reference to gEfiPeiVariableStoreDiscoveredPpiGuid which
contains information whether variable store is available.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 MdePkg/Include/Ppi/ReadOnlyVariable2.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/MdePkg/Include/Ppi/ReadOnlyVariable2.h b/MdePkg/Include/Ppi/ReadOnlyVariable2.h
index 926c0bc82a43..c5a8470565bb 100644
--- a/MdePkg/Include/Ppi/ReadOnlyVariable2.h
+++ b/MdePkg/Include/Ppi/ReadOnlyVariable2.h
@@ -2,7 +2,7 @@
   This file declares Read-only Variable Service2 PPI.
   This ppi permits read-only access to the UEFI variable store during the PEI phase.
 
-Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
   @par Revision Reference:
@@ -106,4 +106,6 @@ struct _EFI_PEI_READ_ONLY_VARIABLE2_PPI {
 
 extern EFI_GUID  gEfiPeiReadOnlyVariable2PpiGuid;
 
+extern EFI_GUID  gEfiPeiVariableStoreDiscoveredPpiGuid;
+
 #endif
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 05/28] MdeModulePkg: Add new ProtectedVariable GUIDs
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (3 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 04/28] MdeModulePkg: Add reference to new Ppi Guid Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-12  9:32   ` Wang, Jian J
  2022-04-29 18:04 ` [Patch v2 06/28] MdeModulePkg: Add new include files Judah Vang
                   ` (24 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Liming Gao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

New ProtectVariable GUIDs for passing variable information
from PEI phase to SMM phase.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 MdeModulePkg/Include/Guid/ProtectedVariable.h | 22 ++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/MdeModulePkg/Include/Guid/ProtectedVariable.h b/MdeModulePkg/Include/Guid/ProtectedVariable.h
new file mode 100644
index 000000000000..0c6e19e0456b
--- /dev/null
+++ b/MdeModulePkg/Include/Guid/ProtectedVariable.h
@@ -0,0 +1,22 @@
+/** @file
+  The GUID definitions specific for protected variable services.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef PROTECTED_VARIABLE_H_
+#define PROTECTED_VARIABLE_H_
+
+#define EDKII_PROTECTED_VARIABLE_GLOBAL_GUID \
+  { 0x8ebf379a, 0xf18e, 0x4728, { 0xa4, 0x10, 0x0, 0xcf, 0x9a, 0x65, 0xbe, 0x91 } }
+
+#define EDKII_METADATA_HMAC_VARIABLE_GUID \
+  { 0xb54cda50, 0xec54, 0x4b20, { 0x85, 0xb4, 0x57, 0xbf, 0x52, 0x98, 0x68, 0x3d } }
+
+extern EFI_GUID  gEdkiiProtectedVariableGlobalGuid;
+extern EFI_GUID  gEdkiiMetaDataHmacVariableGuid;
+extern EFI_GUID  gEdkiiProtectedVariableContextGuid;
+
+#endif // __PROTECTED_VARIABLE_H__
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 06/28] MdeModulePkg: Add new include files
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (4 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 05/28] MdeModulePkg: Add new ProtectedVariable GUIDs Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-12  9:31   ` Wang, Jian J
  2022-04-29 18:04 ` [Patch v2 07/28] MdeModulePkg: Add Null ProtectedVariable Library Judah Vang
                   ` (23 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Liming Gao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add EncryptionVariableLib.h for providing encryption and
decryption services for protected variables.
Add ProtectedVariableLib.h for providing integrity or
variables.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 MdeModulePkg/Include/Library/EncryptionVariableLib.h | 165 +++++
 MdeModulePkg/Include/Library/ProtectedVariableLib.h  | 700 ++++++++++++++++++++
 2 files changed, 865 insertions(+)

diff --git a/MdeModulePkg/Include/Library/EncryptionVariableLib.h b/MdeModulePkg/Include/Library/EncryptionVariableLib.h
new file mode 100644
index 000000000000..c7740e659dcf
--- /dev/null
+++ b/MdeModulePkg/Include/Library/EncryptionVariableLib.h
@@ -0,0 +1,165 @@
+/** @file
+  Provides services to encrypt/decrypt variables.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef ENCRYPTION_VARIABLE_LIB_H_
+#define ENCRYPTION_VARIABLE_LIB_H_
+
+#include <IndustryStandard/Tpm20.h>
+
+#include <Guid/VariableFormat.h>
+
+#include <Library/AuthVariableLib.h>
+
+#define ENC_TYPE_NULL  0
+#define ENC_TYPE_AES   TPM_ALG_AES
+
+typedef struct  _VARIABLE_ENCRYPTION_FLAGS {
+  BOOLEAN    Auth;            // Variable is authenticated or not
+  BOOLEAN    DecryptInPlace;  // Do decryption in place
+  BOOLEAN    Protected;       // Variable is protected or not
+} VARIABLE_ENCRYPTION_FLAGS;
+
+typedef struct _VARIABLE_ENCRYPTION_INFO {
+  AUTH_VARIABLE_INFO           Header;            // Authenticated varabile header
+  VARIABLE_HEADER              *Buffer;           // Pointer to variable buffer
+  UINT64                       StoreIndex;        // Variable store index
+  VOID                         *PlainData;        // Pointer to plain data
+  UINT32                       PlainDataSize;     // Size of plain data
+  VOID                         *CipherData;       // Pointer to cipher data
+  UINT32                       CipherDataSize;    // Size of cipher data
+  UINT32                       CipherHeaderSize;  // Size of cipher header
+  UINT32                       CipherDataType;    // Type of cipher data
+  VOID                         *Key;              // Pointer to encrypt/decrypt key
+  UINT32                       KeySize;           // Size of key
+  VARIABLE_ENCRYPTION_FLAGS    Flags;             // Encryption flags
+} VARIABLE_ENCRYPTION_INFO;
+
+/**
+  Encrypt variable data.
+
+  @param[in, out]   VarInfo   Pointer to structure containing detailed information about a variable.
+
+  @retval EFI_SUCCESS               Function successfully executed.
+  @retval EFI_INVALID_PARAMETER     If ProtectedVarLibContextIn == NULL or ProtectedVarLibContextOut == NULL.
+  @retval EFI_OUT_OF_RESOURCES      Fail to allocate enough resource.
+  @retval EFI_UNSUPPORTED           Unsupported to process authenticated variable.
+
+**/
+EFI_STATUS
+EFIAPI
+EncryptVariable (
+  IN OUT VARIABLE_ENCRYPTION_INFO  *VarInfo
+  );
+
+/**
+  Decrypt variable data.
+
+  If VarEncInfo->CipherData is not NULL, it must holds the cipher data to be
+  decrypted. Otherwise, assume the cipher data from variable data buffer, i.e.
+  VarEncInfo->Header.Data.
+
+  If VarEncInfo->Flags.DecryptInPlace is TRUE, the decrypted data will be put
+  back in the same buffer as cipher buffer got above, after encryption header,
+  which helps to identify later if the data in buffer is decrypted or not. This
+  can avoid repeat decryption when accessing the same variable more than once.
+
+  If VarEncInfo->Flags.DecryptInPlace is FALSE, VarEncInfo->PlainData must be
+  passed in with a valid buffer with VarEncInfo->PlainDataSize set correctly
+  with its size.
+
+  Note the VarEncInfo->PlainData is always pointing to the buffer address with
+  decrypted data without encryption header, and VarEncInfo->PlainDataSize is
+  always the size of original variable data, if this function returned
+  successfully.
+
+  @param[in, out]   VarInfo   Pointer to structure containing detailed
+                              information about a variable.
+
+  @retval EFI_SUCCESS             Variable was decrypted successfully.
+  @retval EFI_INVALID_PARAMETER   Variable information in VarEncInfo is invalid.
+  @retval EFI_BUFFER_TOO_SMALL    VarEncInfo->PlainData is not NULL but
+                                  VarEncInfo->PlainDataSize is too small.
+  @retval EFI_ABORTED             Uknown error occurred during decrypting.
+  @retval EFI_OUT_OF_RESOURCES    Fail to allocate enough resource.
+  @retval EFI_COMPROMISED_DATA    The cipher header is not valid.
+  @retval EFI_UNSUPPORTED         Unsupported to encrypt variable.
+
+**/
+EFI_STATUS
+EFIAPI
+DecryptVariable (
+  IN OUT VARIABLE_ENCRYPTION_INFO  *VarInfo
+  );
+
+/**
+  Get cipher information about a variable, including plaindata size,
+  cipher algorithm type, etc.
+
+  For data passed in with VarEncInfo,
+
+    VarEncInfo->Header.Data
+      - The variable data in normal variable structure.
+    VarEncInfo->Header.DataSize
+      - The size of variable data.
+
+  For data passed out with VarEncInfo (valid only if EFI_SUCCESS is returned),
+
+    VarEncInfo->CipherDataType
+      - ENC_TYPE_NULL, if the variable is not encrypted or has been decrypted;
+      - ENC_TYPE_AES, if the variable is encrypted.
+    VarEncInfo->CipherHeaderSize
+      - Size of cipher header put before encrypted or decrypted data.
+    VarEncInfo->PlainData
+      - NULL, if the variable is encrypted; Or
+      - pointer to original variable data, if the variable has been decrypted.
+    VarEncInfo->PlainDataSize
+      - The size of original variable data
+    VarEncInfo->CipherData
+      - NULL, if the variable is decrypted; Or
+      - pointer to start of encrypted variable data, including encryption header;
+    VarEncInfo->CipherDataSize
+      - The size of encrypted variable data, including encryption header.
+
+  @param[in, out]   VarInfo   Pointer to structure containing detailed
+                              information about a variable.
+
+  @retval EFI_SUCCESS             The information was retrieved successfully.
+  @retval EFI_INVALID_PARAMETER   Variable information in VarEncInfo is invalid.
+  @retval EFI_NOT_FOUND           No cipher information recognized.
+  @retval EFI_UNSUPPORTED         Unsupported interface.
+
+**/
+EFI_STATUS
+EFIAPI
+GetCipherDataInfo (
+  IN  OUT VARIABLE_ENCRYPTION_INFO  *VarInfo
+  );
+
+/**
+  Force set cipher information for a variable, like plaindata size,
+  cipher algorithm type, cipher data etc.
+
+  The destination buffer must be passed via VarEncInfo->Header.Data.
+
+  This method is only used to update and/or change plain data information.
+
+  @param[in, out]   VarInfo   Pointer to structure containing detailed
+                              information about a variable.
+
+  @retval EFI_SUCCESS             The information was updated successfully.
+  @retval EFI_INVALID_PARAMETER   Variable information in VarEncInfo is invalid.
+  @retval EFI_UNSUPPORTED         If this method is not supported.
+
+**/
+EFI_STATUS
+EFIAPI
+SetCipherDataInfo (
+  IN  OUT VARIABLE_ENCRYPTION_INFO  *VarInfo
+  );
+
+#endif //_ENCRYPTION_VARIABLE_LIB_H_
diff --git a/MdeModulePkg/Include/Library/ProtectedVariableLib.h b/MdeModulePkg/Include/Library/ProtectedVariableLib.h
new file mode 100644
index 000000000000..2f57b4ebbc70
--- /dev/null
+++ b/MdeModulePkg/Include/Library/ProtectedVariableLib.h
@@ -0,0 +1,700 @@
+/** @file
+  Defines interfaces of protected variable services for non-volatile variable
+  storage.
+
+Copyright (c) 2020 - 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef PROTECTED_VARIABLE_LIB_H_
+#define PROTECTED_VARIABLE_LIB_H_
+
+#include <PiPei.h>
+#include <PiDxe.h>
+
+#include <Guid/VariableFormat.h>
+
+#include <Protocol/VarCheck.h>
+#include <Protocol/FirmwareVolumeBlock.h>
+
+#include <Library/UefiLib.h>
+#include <Library/EncryptionVariableLib.h>
+
+#pragma pack(1)
+
+typedef struct _VARIABLE_DIGEST_FLAGS {
+  BOOLEAN    Auth;                           // Authenticated variable format
+  BOOLEAN    Valid;                          // Valid variable data in current variable
+  BOOLEAN    Protected;                      // Protected variable (used in calculating HMAC)
+  BOOLEAN    Encrypted;                      // Encrypted variable
+  BOOLEAN    Freeable;                       // Memory reserved for current node can be freed
+  BOOLEAN    CacheIndexAhead;                // Indicates if CacheIndex is Ahead relative to Global structure
+  BOOLEAN    Reserved[2];                    // Reserved fields
+} VARIABLE_DIGEST_FLAGS;
+
+typedef struct _VARIABLE_DIGEST {
+  ///
+  /// Pointer to digest of next variable in a pre-defined rule of order for
+  /// integration verification. In other words, the final HMAC of all
+  /// protected variables is calculated by concatenating digest of each
+  /// variable in the order of this singly linked list.
+  ///
+  EFI_PHYSICAL_ADDRESS     Prev;
+  EFI_PHYSICAL_ADDRESS     Next;
+  ///
+  /// Index to variable in physical store, used to locate the variable directly
+  /// inside the store (Implementation dependent).
+  ///
+  EFI_PHYSICAL_ADDRESS     StoreIndex;
+  ///
+  /// Index to variable in memory cache, used to locate the variable directly
+  /// inside the cache (Implementation dependent).
+  ///
+  EFI_PHYSICAL_ADDRESS     CacheIndex;
+
+  ///
+  /// Pointer to Cache offset within Global Structure
+  ///
+  UINT32                   CacheOffset;
+
+  ///
+  /// Frequently accessed information relating to the variable.
+  ///
+  UINT16                   DigestSize;    // Size of digest value
+  UINT16                   NameSize;      // Size of variable name
+  UINT32                   DataSize;      // Size of variable data
+  UINT32                   PlainDataSize; // Size of plain data of current variable (if encrypted)
+  UINT32                   State;         // State of current variable
+  UINT32                   Attributes;    // Attributes of current variable
+
+  EFI_GUID                 VendorGuid;    // GUID
+  VARIABLE_DIGEST_FLAGS    Flags;         // Variable digest flags
+  //
+  // Data with variable length are put at the end of this structure.
+  //
+  // CHAR16                VariableName[NameSize/2];
+  // UINT8                 DigestValue[DigestSize];
+} VARIABLE_DIGEST;
+
+#pragma pack()
+
+#define VAR_DIG_NAMEOFF(VarDig)  (sizeof (VARIABLE_DIGEST))
+#define VAR_DIG_DIGOFF(VarDig)   (VAR_DIG_NAMEOFF (VarDig) + (VarDig)->NameSize)
+
+#define VAR_DIG_END(VarDig)  (VAR_DIG_DIGOFF (VarDig) + (VarDig)->DigestSize)
+
+#define VAR_DIG_VALUE(VarDig)  (VOID *)((UINTN)(VarDig) + VAR_DIG_DIGOFF (VarDig))
+#define VAR_DIG_NAME(VarDig)   (CHAR16 *)((UINTN)(VarDig) + VAR_DIG_NAMEOFF (VarDig))
+#define VAR_DIG_GUID(VarDig)   &(VAR_DIG_PTR (VarDig)->VendorGuid)
+
+#define VAR_DIG_PTR(Addr)     ((VARIABLE_DIGEST *)(UINTN)(Addr))
+#define VAR_DIG_ADR(Ptr)      ((EFI_PHYSICAL_ADDRESS)(UINTN)(Ptr))
+#define VAR_DIG_NEXT(VarDig)  (VAR_DIG_PTR ((VarDig)->Next))
+#define VAR_DIG_PREV(VarDig)  (VAR_DIG_PTR ((VarDig)->Prev))
+
+#define VAR_INDEX_INVALID  ((UINT64)(-1))
+
+#define VAR_HDR_PTR(Addr)  ((VARIABLE_HEADER *)(UINTN)(Addr))
+
+typedef VARIABLE_ENCRYPTION_INFO PROTECTED_VARIABLE_INFO;
+
+/**
+
+  This function writes data to the NV variable storage at given position.
+
+  Note: Per current variable service architecture, only SMM is allowed to
+        (directly) change NV variable storage.
+
+  @param VariableInfo             Pointer to structure holding details of a variable.
+  @param Offset                   Offset to the given variable to write from.
+  @param Size                     Size of data to be written.
+  @param Buffer                   Pointer to the buffer from which data is written.
+
+  @retval EFI_INVALID_PARAMETER  Invalid parameters passed in.
+  @retval EFI_UNSUPPORTED        Updating NV variable storage is not supported.
+  @retval EFI_OUT_OF_RESOURCES   Not enough resource to complete the operation.
+  @retval EFI_SUCCESS            Variable store successfully updated.
+
+**/
+typedef
+EFI_STATUS
+(EFIAPI *PROTECTED_VAR_LIB_UPDATE_VARIABLE_STORE)(
+  IN  PROTECTED_VARIABLE_INFO     *VariableInfo,
+  IN  UINTN                       Offset,
+  IN  UINT32                      Size,
+  IN  UINT8                       *Buffer
+  );
+
+/**
+  Update the variable region with Variable information.
+
+  @param[in] AuthVariableInfo       Pointer AUTH_VARIABLE_INFO structure for
+                                    input of the variable.
+
+  @retval EFI_SUCCESS               The update operation is success.
+  @retval EFI_INVALID_PARAMETER     Invalid parameter.
+  @retval EFI_WRITE_PROTECTED       Variable is write-protected.
+  @retval EFI_OUT_OF_RESOURCES      There is not enough resource.
+
+**/
+typedef
+EFI_STATUS
+(EFIAPI *PROTECTED_VAR_LIB_UPDATE_VARIABLE)(
+  IN AUTH_VARIABLE_INFO     *AuthVariableInfo
+  );
+
+/**
+
+  Retrieve details about a variable and return them in VariableInfo->Header.
+
+  If VariableInfo->Address is given, this function will calculate its offset
+  relative to given variable storage via VariableStore; Otherwise, it will try
+  other internal variable storages or cached copies. It's assumed that, for all
+  copies of NV variable storage, all variables are stored in the same relative
+  position. If VariableInfo->Address is found in the range of any storage copies,
+  its offset relative to that storage should be the same in other copies.
+
+  If VariableInfo->Offset is given (non-zero) but not VariableInfo->Address,
+  this function will return the variable memory address inside VariableStore,
+  if given, via VariableInfo->Address; Otherwise, the address of other storage
+  copies will be returned, if any.
+
+  For a new variable whose offset has not been determined, a value of -1 as
+  VariableInfo->Offset should be passed to skip the offset calculation.
+
+  @param VariableInfo             Pointer to variable information.
+
+  @retval EFI_INVALID_PARAMETER  VariableInfo is NULL or both VariableInfo->Address
+                                 and VariableInfo->Offset are NULL (0).
+  @retval EFI_NOT_FOUND          If given Address or Offset is out of range of
+                                 any given or internal storage copies.
+  @retval EFI_SUCCESS            Variable details are retrieved successfully.
+
+**/
+typedef
+EFI_STATUS
+(EFIAPI *PROTECTED_VAR_LIB_GET_VAR_INFO)(
+  IN  OUT PROTECTED_VARIABLE_INFO   *VariableInfo
+  );
+
+/**
+
+  Retrieve details of the variable next to given variable within VariableStore.
+
+  If VarInfo->Address is NULL, the first one in VariableStore is returned.
+
+  VariableStart and/or VariableEnd can be given optionally for the situation
+  in which the valid storage space is smaller than the VariableStore->Size.
+  This usually happens when PEI variable services make a compact variable
+  cache to save memory, which cannot make use VariableStore->Size to determine
+  the correct variable storage range.
+
+  @param VariableStore            Pointer to a variable storage. It's optional.
+  @param VariableStart            Start point of valid range in VariableStore.
+  @param VariableEnd              End point of valid range in VariableStore.
+  @param VariableInfo             Pointer to variable information.
+
+  @retval EFI_INVALID_PARAMETER  VariableInfo or VariableStore is NULL.
+  @retval EFI_NOT_FOUND          If the end of VariableStore is reached.
+  @retval EFI_SUCCESS            The next variable is retrieved successfully.
+
+**/
+typedef
+EFI_STATUS
+(EFIAPI *PROTECTED_VAR_LIB_GET_NEXT_VAR_INFO)(
+  IN  OUT PROTECTED_VARIABLE_INFO   *VariableInfo
+  );
+
+typedef
+EFI_STATUS
+(EFIAPI *DIGEST_METHOD_CALLBACK)(
+  IN      VARIABLE_HEADER           *Variable,
+  IN  OUT VARIABLE_DIGEST        *Digest
+  );
+
+/**
+
+  Initialize a memory copy of NV variable storage.
+
+  To save memory consumption (especially in PEI phase), it's allowed to cache
+  only valid variables. In such case, an index table recording offset of each
+  valid variables could be employed. The index table makes sure the cached copy
+  to be synchronized with the original copy in NV variable storage. To avoid
+  TOCTOU issue, once the variables are cached in memory and verified, NV
+  variable storage should not be used to read variable information. The cached
+  copy should be used instead.
+
+  If StoreCacheBase is not given, this function should return the required
+  cache size and valid variable number, if VariableNumber is not NULL. Then
+  the caller can prepare correct cache buffer and index table buffer before
+  next calling.
+
+  @param[in]      CacheBase       Base address of NV variable storage cache.
+  @param[in]      CacheSize       Size of CacheBuffer.
+  @param[out]     CacheSize       Size of required cache buffer.
+  @param[out]     DigBuffer       Base address of digest of each variable.
+  @param[in, out] DigBufferSize   Digest size of one variable if DigestBuffer is NULL.
+                                  Size of DigestBuffer if DigestBuffer is NOT NULL.
+  @param[out]     DigSize         Required size of DigestBuffer if DigestBuffer is NULL.
+  @param[out]     DigMethod       Method used to generate digest for each variable.
+  @param[out]     VarNumber       Number of valid variables.
+  @param[out]     AuthFlag        Auth-variable indicator.
+
+  @retval EFI_INVALID_PARAMETER   CacheSize is NULL; Or,
+                                  StoreCacheBase is 0 but *CacheSize it not.
+  @retval EFI_VOLUME_CORRUPTED    If original NV variable storage is corrupted.
+  @retval EFI_BUFFER_TOO_SMALL    If *CacheSize is smaller than required memory.
+  @retval EFI_SUCCESS             The cached variable storage is initialized.
+
+**/
+typedef
+EFI_STATUS
+(EFIAPI *PROTECTED_VAR_LIB_INIT_VAR_STORE)(
+  OUT  VOID                      *CacheBase OPTIONAL,
+  IN OUT  UINT32                    *CacheSize OPTIONAL,
+  OUT  VOID                      *DigBuffer OPTIONAL,
+  IN OUT  UINT32                    *DigBufferSize OPTIONAL,
+  IN      UINT32                    DigSize OPTIONAL,
+  IN      DIGEST_METHOD_CALLBACK    DigMethod OPTIONAL,
+  OUT  UINT32                    *VarNumber OPTIONAL,
+  OUT  BOOLEAN                   *AuthFlag OPTIONAL
+  );
+
+/**
+
+  Initiate a variable retrieval in SMM environment from non-SMM environment.
+
+  This is usually required in BS/RT environment when local cached copy is in
+  encrypted form. Variable decryption can only be done in SMM environment.
+
+  @param[in]      VariableName       Name of Variable to be found.
+  @param[in]      VendorGuid         Variable vendor GUID.
+  @param[out]     Attributes         Attribute value of the variable found.
+  @param[in, out] DataSize           Size of Data found. If size is less than the
+                                     data, this value contains the required size.
+  @param[out]     Data               Data pointer.
+
+  @retval EFI_SUCCESS                Found the specified variable.
+  @retval EFI_INVALID_PARAMETER      Invalid parameter.
+  @retval EFI_NOT_FOUND              The specified variable could not be found.
+
+**/
+typedef
+EFI_STATUS
+(EFIAPI *PROTECTED_VAR_LIB_FIND_VAR_SMM)(
+  IN      CHAR16                     *VariableName,
+  IN      EFI_GUID                   *VendorGuid,
+  OUT UINT32                     *Attributes OPTIONAL,
+  IN  OUT UINTN                      *DataSize,
+  OUT VOID                       *Data OPTIONAL
+  );
+
+/**
+  Check if a variable is user variable or not.
+
+  @param[in] Variable   Pointer to variable header.
+
+  @retval TRUE          User variable.
+  @retval FALSE         System variable.
+
+**/
+typedef
+BOOLEAN
+(EFIAPI *PROTECTED_VAR_LIB_IS_USER_VAR)(
+  IN VARIABLE_HEADER    *Variable
+  );
+
+/**
+  Check if a HOB variable store is available or not.
+
+  @retval EFI_NOT_READY  HOB variable store info not available.
+  @retval EFI_NOT_FOUND  HOB variable store is NOT available.
+  @retval EFI_SUCCESS    HOB variable store is available.
+**/
+typedef
+EFI_STATUS
+(EFIAPI *PROTECTED_VAR_LIB_HOB_STORE_AVAILABLE)(
+  VOID
+  );
+
+typedef enum {
+  FromPeiModule,
+  FromBootServiceModule,
+  FromRuntimeModule,
+  FromSmmModule
+} VARIABLE_SERVICE_USER;
+
+#pragma pack(1)
+
+#define PROTECTED_VARIABLE_CONTEXT_IN_STRUCT_VERSION  0x02
+
+typedef struct _PROTECTED_VARIABLE_CONTEXT_IN {
+  UINT32                                     StructVersion;
+  UINT32                                     StructSize;
+  UINT32                                     MaxVariableSize;
+
+  VARIABLE_SERVICE_USER                      VariableServiceUser;
+
+  PROTECTED_VAR_LIB_FIND_VAR_SMM             FindVariableSmm;
+  PROTECTED_VAR_LIB_GET_VAR_INFO             GetVariableInfo;
+  PROTECTED_VAR_LIB_GET_NEXT_VAR_INFO        GetNextVariableInfo;
+  PROTECTED_VAR_LIB_UPDATE_VARIABLE_STORE    UpdateVariableStore;
+  PROTECTED_VAR_LIB_UPDATE_VARIABLE          UpdateVariable;
+  PROTECTED_VAR_LIB_HOB_STORE_AVAILABLE      IsHobVariableStoreAvailable;
+} PROTECTED_VARIABLE_CONTEXT_IN;
+
+#pragma pack()
+
+/**
+
+  Initialization for protected variable services.
+
+  If this initialization failed upon any error, the whole variable services
+  should not be used.  A system reset might be needed to re-construct NV
+  variable storage to be the default state.
+
+  @param[in]  ContextIn   Pointer to variable service context needed by
+                          protected variable.
+
+  @retval EFI_SUCCESS               Protected variable services are ready.
+  @retval EFI_INVALID_PARAMETER     If ContextIn == NULL or something missing or
+                                    mismatching in the content in ContextIn.
+  @retval EFI_COMPROMISED_DATA      If failed to check integrity of protected variables.
+  @retval EFI_OUT_OF_RESOURCES      Fail to allocate enough resource.
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibInitialize (
+  IN  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn
+  );
+
+/**
+
+  An alternative version of ProtectedVariableLibGetData to get plain data, if
+  encrypted, from given variable, for different use cases.
+
+  @param[in,out]      VarInfo     Pointer to structure containing variable information.
+
+  @retval EFI_SUCCESS               Found the specified variable.
+  @retval EFI_INVALID_PARAMETER     VarInfo is NULL or both VarInfo->Address and
+                                    VarInfo->Offset are invalid.
+  @retval EFI_NOT_FOUND             The specified variable could not be found.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetByInfo (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
+  );
+
+/**
+  This service retrieves a variable's value using its name and GUID.
+
+  Read the specified variable from the UEFI variable store. If the Data
+  buffer is too small to hold the contents of the variable, the error
+  EFI_BUFFER_TOO_SMALL is returned and DataSize is set to the required buffer
+  size to obtain the data.
+
+  @param  VariableName          A pointer to a null-terminated string that is the variable's name.
+  @param  VariableGuid          A pointer to an EFI_GUID that is the variable's GUID. The combination of
+                                VariableGuid and VariableName must be unique.
+  @param  Attributes            If non-NULL, on return, points to the variable's attributes.
+  @param  DataSize              On entry, points to the size in bytes of the Data buffer.
+                                On return, points to the size of the data returned in Data.
+  @param  Data                  Points to the buffer which will hold the returned variable value.
+                                May be NULL with a zero DataSize in order to determine the size of the buffer needed.
+
+  @retval EFI_SUCCESS           The variable was read successfully.
+  @retval EFI_NOT_FOUND         The variable was be found.
+  @retval EFI_BUFFER_TOO_SMALL  The DataSize is too small for the resulting data.
+                                DataSize is updated with the size required for
+                                the specified variable.
+  @retval EFI_INVALID_PARAMETER VariableName, VariableGuid, DataSize or Data is NULL.
+  @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetByName (
+  IN      CONST  CHAR16    *VariableName,
+  IN      CONST  EFI_GUID  *VariableGuid,
+  OUT UINT32               *Attributes,
+  IN  OUT UINTN            *DataSize,
+  OUT VOID                 *Data OPTIONAL
+  );
+
+/**
+
+  Retrieve plain data, if encrypted, of given variable.
+
+  If variable encryption is employed, this function will initiate a SMM request
+  to get the plain data. Due to security consideration, the decryption can only
+  be done in SMM environment.
+
+  @param[in]      Variable           Pointer to header of a Variable.
+  @param[out]     Data               Pointer to plain data of the given variable.
+  @param[in, out] DataSize           Size of data returned or data buffer needed.
+  @param[in]      AuthFlag           Auth-variable indicator.
+
+  @retval EFI_SUCCESS                Found the specified variable.
+  @retval EFI_INVALID_PARAMETER      Invalid parameter.
+  @retval EFI_NOT_FOUND              The specified variable could not be found.
+  @retval EFI_BUFFER_TOO_SMALL       If *DataSize is smaller than needed.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetByBuffer (
+  IN      VARIABLE_HEADER  *Variable,
+  IN  OUT VOID             *Data,
+  IN  OUT UINT32           *DataSize,
+  IN      BOOLEAN          AuthFlag
+  );
+
+/**
+
+  Prepare for variable update.
+
+  This is needed only once during current boot to mitigate replay attack. Its
+  major job is to advance RPMC (Replay Protected Monotonic Counter).
+
+  @retval EFI_SUCCESS             Variable is ready to update hereafter.
+  @retval EFI_UNSUPPORTED         Updating variable is not supported.
+  @retval EFI_DEVICE_ERROR        Error in advancing RPMC.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibWriteInit (
+  VOID
+  );
+
+/**
+
+  Update a variable with protection provided by this library.
+
+  If variable encryption is employed, the new variable data will be encrypted
+  before being written to NV variable storage.
+
+  A special variable, called "MetaDataHmacVar", will always be updated along
+  with variable being updated to reflect the changes (HMAC value) of all
+  protected valid variables. The only exceptions, currently, are variable
+  "MetaDataHmacVar" itself and variable "VarErrorLog".
+
+  The buffer passed by NewVariable must be double of maximum variable size,
+  which allows to pass the "MetaDataHmacVar" back to caller along with encrypted
+  new variable data, if any. This can make sure the new variable data and
+  "MetaDataHmacVar" can be written at almost the same time to reduce the chance
+  of compromising the integrity.
+
+  If *NewVariableSize is zero, it means to delete variable passed by CurrVariable
+  and/or CurrVariableInDel. "MetaDataHmacVar" will be updated as well in such
+  case because of less variables in storage. NewVariable should be always passed
+  in to convey new "MetaDataHmacVar" back.
+
+  @param[in,out]  CurrVariable        Variable to be updated. It's NULL if
+                                      adding a new variable.
+  @param[in,out]  CurrVariableInDel   In-delete-transition copy of updating variable.
+  @param[in]      NewVariable         Buffer of new variable data.
+  @param[out]     NewVariable         Buffer of "MetaDataHmacVar" and new
+                                      variable (encrypted).
+  @param[in]      NewVariableSize     Size of NewVariable.
+  @param[out]     NewVariableSize     Size of (encrypted) NewVariable and
+                                      "MetaDataHmacVar".
+
+  @retval EFI_SUCCESS             The variable is updated with protection successfully.
+  @retval EFI_INVALID_PARAMETER   NewVariable is NULL.
+  @retval EFI_NOT_FOUND           Information missing to finish the operation.
+  @retval EFI_ABORTED             Failed to encrypt variable or calculate HMAC.
+  @retval EFI_NOT_READY           The RPMC device is not yet initialized.
+  @retval EFI_DEVICE_ERROR        The RPMC device has error in updating.
+  @retval EFI_ACCESS_DENIED       The given variable is not allowed to update.
+                                  Currently this only happens on updating
+                                  "MetaDataHmacVar" from code outside of this
+                                  library.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibUpdate (
+  IN  OUT VARIABLE_HEADER  *CurrVariable OPTIONAL,
+  IN  OUT VARIABLE_HEADER  *CurrVariableInDel OPTIONAL,
+  IN  OUT VARIABLE_HEADER  *NewVariable,
+  IN  OUT UINTN            *NewVariableSize
+  );
+
+/**
+
+  Finalize a variable updating after it's written to NV variable storage
+  successfully.
+
+  This usually includes works like increasing RPMC, synchronizing local cache,
+  updating new position of "MetaDataHmacVar", deleting old copy of "MetaDataHmacVar"
+  completely, etc.
+
+  @param[in]      NewVariable       Buffer of new variables and MetaDataHmacVar.
+  @param[in]      VariableSize      Size of buffer pointed by NewVariable.
+  @param[in]      Offset            Offset to NV variable storage from where the new
+                                    variable and MetaDataHmacVar have been written.
+
+  @retval EFI_SUCCESS         No problem in winding up the variable write operation.
+  @retval Others              Failed to updating state of old copy of updated
+                              variable, or failed to increase RPMC, etc.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibWriteFinal (
+  IN  VARIABLE_HEADER  *NewVariable,
+  IN  UINTN            VariableSize,
+  IN  UINT64           StoreIndex
+  );
+
+/**
+  Return the request variable name and GUID as per StoreIndex.
+
+  This function is called multiple times to retrieve the VariableName
+  and VariableGuid of all variables currently available in the system.
+  On each call, the previous results are passed into the interface,
+  and, on return, the interface returns the data for the next
+  interface. When the entire variable list has been returned,
+  EFI_NOT_FOUND is returned.
+
+  @param  This              A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
+
+  @param  VariableNameSize  On entry, points to the size of the buffer pointed to by VariableName.
+                            On return, the size of the variable name buffer.
+  @param  VariableName      On entry, a pointer to a null-terminated string that is the variable's name.
+                            On return, points to the next variable's null-terminated name string.
+  @param  VariableGuid      On entry, a pointer to an EFI_GUID that is the variable's GUID.
+                            On return, a pointer to the next variable's GUID.
+
+  @retval EFI_SUCCESS           The variable was read successfully.
+  @retval EFI_NOT_FOUND         The variable could not be found.
+  @retval EFI_BUFFER_TOO_SMALL  The VariableNameSize is too small for the resulting
+                                data. VariableNameSize is updated with the size
+                                required for the specified variable.
+  @retval EFI_INVALID_PARAMETER VariableName, VariableGuid or
+                                VariableNameSize is NULL.
+  @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibFind (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
+  );
+
+/**
+  Return the next variable name and GUID.
+
+  This function is called multiple times to retrieve the VariableName
+  and VariableGuid of all variables currently available in the system.
+  On each call, the previous results are passed into the interface,
+  and, on return, the interface returns the data for the next
+  interface. When the entire variable list has been returned,
+  EFI_NOT_FOUND is returned.
+
+  @param  VariableNameSize  On entry, points to the size of the buffer pointed to by VariableName.
+                            On return, the size of the variable name buffer.
+  @param  VariableName      On entry, a pointer to a null-terminated string that is the variable's name.
+                            On return, points to the next variable's null-terminated name string.
+  @param  VariableGuid      On entry, a pointer to an EFI_GUID that is the variable's GUID.
+                            On return, a pointer to the next variable's GUID.
+
+  @retval EFI_SUCCESS           The variable was read successfully.
+  @retval EFI_NOT_FOUND         The variable could not be found.
+  @retval EFI_BUFFER_TOO_SMALL  The VariableNameSize is too small for the resulting
+                                data. VariableNameSize is updated with the size
+                                required for the specified variable.
+  @retval EFI_INVALID_PARAMETER VariableName, VariableGuid or
+                                VariableNameSize is NULL.
+  @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibFindNext (
+  IN OUT UINTN     *VariableNameSize,
+  IN OUT CHAR16    *VariableName,
+  IN OUT EFI_GUID  *VariableGuid
+  );
+
+/**
+  Find variable via information in data structure PROTECTED_VARIABLE_INFO.
+
+   If VarInfo->StoreIndex is given and valid, always used it to search variable
+   in store. Otherwise, search the variable via variable name and guid pointed
+   by VarInfo->Header.VariableName and VarInfo->Header.VendorGuid.
+
+  @param VarInfo    Pointer to data containing variable information.
+
+  @return EFI_SUCCESS           Found the variable.
+  @return EFI_INVALID_PARAMETER No valid variable information is given.
+  @return EFI_NOT_FOUND         The given variable was not found or no more
+                                variables available.
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibFindNextEx (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
+  );
+
+/**
+  Refresh variable information changed by variable service.
+
+  @param Variable         Pointer to buffer of the updated variable.
+  @param VariableSize     Size of variable pointed by Variable.
+  @param StoreIndex       New index of the variable in store.
+  @param RefreshData      Flag to indicate if the variable has been updated.
+
+  @return EFI_SUCCESS     No error occurred in updating.
+  @return EFI_NOT_FOUND   The given variable was not found in
+                          ProtectedVariableLib.
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibRefresh (
+  IN  VARIABLE_HEADER  *Variable,
+  IN  UINTN            VariableSize,
+  IN  UINT64           StoreIndex,
+  IN  BOOLEAN          RefreshData
+  );
+
+/**
+  Refresh variable information changed by variable service.
+
+  @param Buffer           Pointer to a pointer of buffer.
+  @param NumElements      Pointer to number of elements in list.
+
+
+  @return EFI_SUCCESS     Successfully retrieved sorted list.
+  @return others          Unsuccessful.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetSortedList (
+  IN  OUT  EFI_PHYSICAL_ADDRESS  **Buffer,
+  IN  OUT  UINTN                 *NumElements
+  );
+
+/**
+
+  Determine if the variable is the HMAC variable
+
+  @param VariableName   Pointer to variable name.
+
+  @return TRUE      Variable is HMAC variable
+  @return FALSE     Variable is not HMAC variable
+
+**/
+BOOLEAN
+ProtectedVariableLibIsHmac (
+  IN CHAR16  *VariableName
+  );
+
+#endif
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 07/28] MdeModulePkg: Add Null ProtectedVariable Library
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (5 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 06/28] MdeModulePkg: Add new include files Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-22  8:38   ` Wang, Jian J
  2022-04-29 18:04 ` [Patch v2 08/28] MdeModulePkg: Add new Variable functionality Judah Vang
                   ` (22 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Liming Gao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add Null versions of the ProtectedVariable Library.
This will be the default libraries for platforms that
do not support ProtectedVariable.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf |  34 ++
 MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariable.c          | 449 ++++++++++++++++++++
 2 files changed, 483 insertions(+)

diff --git a/MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf b/MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
new file mode 100644
index 000000000000..6a17191c4e1e
--- /dev/null
+++ b/MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
@@ -0,0 +1,34 @@
+## @file
+#  Provides null version of protected variable services.
+#
+#  Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010029
+  BASE_NAME                      = ProtectedVariableLibNull
+  FILE_GUID                      = 352C6A1B-403A-4E37-8517-FAA50BC45251
+  MODULE_TYPE                    = BASE
+  VERSION_STRING                 = 0.1
+  LIBRARY_CLASS                  = ProtectedVariableLib
+
+#
+# The following information is for reference only and not required by the build tools.
+#
+#  VALID_ARCHITECTURES           = IA32 X64
+#
+
+[Sources]
+  ProtectedVariable.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+
+[LibraryClasses]
+  BaseLib
+  BaseMemoryLib
+  DebugLib
+
diff --git a/MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariable.c b/MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariable.c
new file mode 100644
index 000000000000..cc1e16c1a671
--- /dev/null
+++ b/MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariable.c
@@ -0,0 +1,449 @@
+/** @file
+  NULL version of ProtectedVariableLib used to disable protected variable services.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <PiDxe.h>
+#include <Uefi.h>
+
+#include <Library/DebugLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/ProtectedVariableLib.h>
+
+/**
+
+  Initialization for protected varibale services.
+
+  @param[in]  ContextIn   Pointer to variable service context needed by
+                          protected variable.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibInitialize (
+  IN  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Get a verified copy of NV variable storage.
+
+  @param[out]     VariableFvHeader      Pointer to the header of whole NV firmware volume.
+  @param[out]     VariableStoreHeader   Pointer to the header of variable storage.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetStore (
+  OUT EFI_FIRMWARE_VOLUME_HEADER  **VariableFvHeader,
+  OUT VARIABLE_STORE_HEADER       **VariableStoreHeader
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Prepare for variable update.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibWriteInit (
+  VOID
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Update a variable with protection provided by this library.
+
+  @param[in,out]  CurrVariable        Variable to be updated. It's NULL if
+                                      adding a new variable.
+  @param[in]      CurrVariableInDel   In-delete-transiion copy of updating variable.
+  @param[in,out]  NewVariable         Buffer of new variable data.
+                                      Buffer of "MetaDataHmacVar" and new
+                                      variable (encrypted).
+  @param[in,out]  NewVariableSize     Size of NewVariable.
+                                      Size of (encrypted) NewVariable and
+                                      "MetaDataHmacVar".
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibUpdate (
+  IN  OUT VARIABLE_HEADER  *CurrVariable,
+  IN      VARIABLE_HEADER  *CurrVariableInDel,
+  IN  OUT VARIABLE_HEADER  *NewVariable,
+  IN  OUT UINTN            *NewVariableSize
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Finalize a variable updating after it's written to NV variable storage
+  successfully.
+
+  @param[in]      NewVariable       Buffer of new variables and MetaDataHmacVar.
+  @param[in]      VariableSize      Size of buffer pointed by NewVariable.
+  @param[in]      StoreIndex        New index of the variable in store.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibWriteFinal (
+  IN  VARIABLE_HEADER  *NewVariable,
+  IN  UINTN            VariableSize,
+  IN  UINT64           StoreIndex
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Perform garbage collection against the cached copy of NV variable storage.
+
+  @param[in]      VariableStoreBuffer         Buffer used to do the reclaim.
+  @param[out]     LastVariableOffset          New free space start point.
+  @param[in]      CurrVariableOffset          Offset of existing variable.
+  @param[in]      CurrVariableInDelOffset     Offset of old copy of existing variable.
+  @param[in,out]  NewVariable                 Buffer of new variable data.
+  @param[in]      NewVariableSize             Size of new variable data.
+  @param[in,out]  HwErrVariableTotalSize      Total size of variables with HR attribute.
+  @param[in,out]  CommonVariableTotalSize     Total size of common variables.
+  @param[in,out]  CommonUserVariableTotalSize Total size of user variables.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibReclaim (
+  IN      VARIABLE_STORE_HEADER  *VariableStoreBuffer,
+  OUT     UINTN                  *LastVariableOffset,
+  IN      UINTN                  CurrVariableOffset,
+  IN      UINTN                  CurrVariableInDelOffset,
+  IN  OUT VARIABLE_HEADER        **NewVariable,
+  IN      UINTN                  NewVariableSize,
+  IN  OUT UINTN                  *HwErrVariableTotalSize,
+  IN  OUT UINTN                  *CommonVariableTotalSize,
+  IN  OUT UINTN                  *CommonUserVariableTotalSize
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  An alternative version of ProtectedVariableLibGetData to get plain data, if
+  encrypted, from given variable, for different use cases.
+
+  @param[in,out]      VarInfo     Pointer to structure containing variable information.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetDataInfo (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Retrieve plain data, if encrypted, of given variable.
+
+  @param[in]      Variable           Pointer to header of a Variable.
+  @param[in,out]  Data               Pointer to plain data of the given variable.
+  @param[in,out]  DataSize           Size of data returned or data buffer needed.
+  @param[in]      AuthFlag           Auth-variable indicator.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetData (
+  IN      VARIABLE_HEADER  *Variable,
+  IN  OUT VOID             *Data,
+  IN  OUT UINT32           *DataSize,
+  IN      BOOLEAN          AuthFlag
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Retrieve next protected variable stub.
+
+  @param[in,out]      VarInfo     Pointer to structure containing variable information.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetNextEx (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Retrieve next protected variable.
+
+  @param[in,out]      VariableNameSize    Pointer to size of variable name.
+  @param[in,out]      VariableName        Pointer to variable name.
+  @param[in,out]      VariableGuid        Pointer to vairable GUID.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetNext (
+  IN OUT UINTN     *VariableNameSize,
+  IN OUT CHAR16    *VariableName,
+  IN OUT EFI_GUID  *VariableGuid
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Get the specified protected variable.
+
+  @param[in]      VariableName      Pointer to variable name.
+  @param[in]      VariableGuid      Pointer to vairable GUID.
+  @param[out]     Attributes        Pointer to attributes.
+  @param[in,out]  DataSize          Pointer to data size.
+  @param[out]     Data              Pointer to data.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGet (
+  IN      CONST  CHAR16    *VariableName,
+  IN      CONST  EFI_GUID  *VariableGuid,
+  OUT UINT32               *Attributes,
+  IN  OUT UINTN            *DataSize,
+  OUT VOID                 *Data OPTIONAL
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Find the protected variable.
+
+  @param[in,out]      VarInfo     Pointer to structure containing variable information.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibFind (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Find next protected variable.
+
+  @param[in,out]      VariableNameSize    Pointer to size of variable name.
+  @param[in,out]      VariableName        Pointer to variable name.
+  @param[in,out]      VariableGuid        Pointer to vairable GUID.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibFindNext (
+  IN OUT UINTN     *VariableNameSize,
+  IN OUT CHAR16    *VariableName,
+  IN OUT EFI_GUID  *VariableGuid
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Find next protected variable stub.
+
+  @param[in,out]      VarInfo     Pointer to structure containing variable information.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibFindNextEx (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Get protected variable by information.
+
+  @param[in,out]      VarInfo     Pointer to structure containing variable information.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetByInfo (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Get protected variable by name.
+
+  @param[in]      VariableName      Pointer to variable name.
+  @param[in]      VariableGuid      Pointer to vairable GUID.
+  @param[out]     Attributes        Pointer to attributes.
+  @param[in,out]  DataSize          Pointer to data size.
+  @param[out]     Data              Pointer to data.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetByName (
+  IN      CONST  CHAR16    *VariableName,
+  IN      CONST  EFI_GUID  *VariableGuid,
+  OUT UINT32               *Attributes,
+  IN  OUT UINTN            *DataSize,
+  OUT VOID                 *Data OPTIONAL
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Get protected variable by name.
+
+  @param[in]      Variable      Pointer to variable name.
+  @param[in,out]  Data          Pointer to variable data.
+  @param[in,out]  DataSize      Pointer to data size.
+  @param[in]      AuthFlag      Authenticate flag.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetByBuffer (
+  IN      VARIABLE_HEADER  *Variable,
+  IN  OUT VOID             *Data,
+  IN  OUT UINT32           *DataSize,
+  IN      BOOLEAN          AuthFlag
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+  Refresh variable information changed by variable service.
+
+  @param[in]  Variable         Pointer to buffer of the updated variable.
+  @param[in]  VariableSize     Size of variable pointed by Variable.
+  @param[in]  StoreIndex       New index of the variable in store.
+  @param[in]  RefreshData      Flag to indicate if the variable has been updated.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibRefresh (
+  IN  VARIABLE_HEADER  *Variable,
+  IN  UINTN            VariableSize,
+  IN  UINT64           StoreIndex,
+  IN  BOOLEAN          RefreshData
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Get sorted protected variable list.
+
+  @param[in,out]  Buffer        Pointer to buffer.
+  @param[in,out]  NumElements   Pointer to number of elements.
+
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetSortedList (
+  IN  OUT  EFI_PHYSICAL_ADDRESS  **Buffer,
+  IN  OUT  UINTN                 *NumElements
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Determine if the variable is the HMAC variable.
+
+  @param[in]  VariableName   Pointer to variable name.
+
+  @return FALSE     Variable is not HMAC variable
+
+**/
+BOOLEAN
+ProtectedVariableLibIsHmac (
+  IN CHAR16  *VariableName
+  )
+{
+  return FALSE;
+}
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 08/28] MdeModulePkg: Add new Variable functionality
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (6 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 07/28] MdeModulePkg: Add Null ProtectedVariable Library Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-22 10:24   ` Wang, Jian J
  2022-04-29 18:04 ` [Patch v2 09/28] MdeModulePkg: Add support for Protected Variables Judah Vang
                   ` (21 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Liming Gao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Provide new APIs for retrieving variable information.
Add new function stubs for retrieving Protected
variable information.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 MdeModulePkg/Universal/Variable/Pei/VariablePei.inf   |  10 +-
 MdeModulePkg/Universal/Variable/Pei/Variable.h        |  80 +-
 MdeModulePkg/Universal/Variable/Pei/VariableParsing.h | 309 +++++++
 MdeModulePkg/Universal/Variable/Pei/VariableStore.h   | 116 +++
 MdeModulePkg/Universal/Variable/Pei/Variable.c        | 886 +++---------------
 MdeModulePkg/Universal/Variable/Pei/VariableParsing.c | 941 ++++++++++++++++++++
 MdeModulePkg/Universal/Variable/Pei/VariableStore.c   | 305 +++++++
 7 files changed, 1891 insertions(+), 756 deletions(-)

diff --git a/MdeModulePkg/Universal/Variable/Pei/VariablePei.inf b/MdeModulePkg/Universal/Variable/Pei/VariablePei.inf
index 7cbdd2385e8f..af172126a011 100644
--- a/MdeModulePkg/Universal/Variable/Pei/VariablePei.inf
+++ b/MdeModulePkg/Universal/Variable/Pei/VariablePei.inf
@@ -3,7 +3,7 @@
 #
 #  This module implements ReadOnly Variable Services required by PEIM and installs PEI ReadOnly Varaiable2 PPI.
 #
-#  Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
+#  Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
 #  SPDX-License-Identifier: BSD-2-Clause-Patent
 #
 ##
@@ -26,6 +26,10 @@ [Defines]
 [Sources]
   Variable.c
   Variable.h
+  VariableStore.c
+  VariableStore.h
+  VariableParsing.c
+  VariableParsing.h
 
 [Packages]
   MdePkg/MdePkg.dec
@@ -39,6 +43,7 @@ [LibraryClasses]
   DebugLib
   PeiServicesTablePointerLib
   PeiServicesLib
+  ProtectedVariableLib
 
 [Guids]
   ## CONSUMES             ## GUID # Variable store header
@@ -56,7 +61,8 @@ [Guids]
   gEdkiiFaultTolerantWriteGuid
 
 [Ppis]
-  gEfiPeiReadOnlyVariable2PpiGuid   ## PRODUCES
+  gEfiPeiReadOnlyVariable2PpiGuid        ## PRODUCES
+  gEfiPeiVariableStoreDiscoveredPpiGuid  ## CONSUMES
 
 [Pcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageVariableBase      ## SOMETIMES_CONSUMES
diff --git a/MdeModulePkg/Universal/Variable/Pei/Variable.h b/MdeModulePkg/Universal/Variable/Pei/Variable.h
index 7f9ad5bfc357..115426edd626 100644
--- a/MdeModulePkg/Universal/Variable/Pei/Variable.h
+++ b/MdeModulePkg/Universal/Variable/Pei/Variable.h
@@ -2,7 +2,7 @@
   The internal header file includes the common header files, defines
   internal structure and functions used by PeiVariable module.
 
-Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
@@ -20,11 +20,13 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 #include <Library/BaseMemoryLib.h>
 #include <Library/PeiServicesTablePointerLib.h>
 #include <Library/PeiServicesLib.h>
+#include <Library/ProtectedVariableLib.h>
 
 #include <Guid/VariableFormat.h>
 #include <Guid/VariableIndexTable.h>
 #include <Guid/SystemNvDataGuid.h>
 #include <Guid/FaultTolerantWrite.h>
+#include <Guid/ProtectedVariable.h>
 
 typedef enum {
   VariableStoreTypeHob,
@@ -142,4 +144,80 @@ PeiGetNextVariableName (
   IN OUT EFI_GUID                            *VariableGuid
   );
 
+/**
+  This service retrieves a variable's value using its name and GUID.
+
+  Read the specified variable from the UEFI variable store. If the Data
+  buffer is too small to hold the contents of the variable, the error
+  EFI_BUFFER_TOO_SMALL is returned and DataSize is set to the required buffer
+  size to obtain the data.
+
+  @param  This                  A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
+  @param  VariableName          A pointer to a null-terminated string that is the variable's name.
+  @param  VariableGuid          A pointer to an EFI_GUID that is the variable's GUID. The combination of
+                                VariableGuid and VariableName must be unique.
+  @param  Attributes            If non-NULL, on return, points to the variable's attributes.
+  @param  DataSize              On entry, points to the size in bytes of the Data buffer.
+                                On return, points to the size of the data returned in Data.
+  @param  Data                  Points to the buffer which will hold the returned variable value.
+                                May be NULL with a zero DataSize in order to determine the size of the buffer needed.
+
+  @retval EFI_SUCCESS           The variable was read successfully.
+  @retval EFI_NOT_FOUND         The variable was not found.
+  @retval EFI_BUFFER_TOO_SMALL  The DataSize is too small for the resulting data.
+                                DataSize is updated with the size required for
+                                the specified variable.
+  @retval EFI_INVALID_PARAMETER VariableName, VariableGuid, DataSize or Data is NULL.
+  @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
+
+**/
+EFI_STATUS
+EFIAPI
+PeiGetVariableEx (
+  IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI  *This,
+  IN CONST  CHAR16                           *VariableName,
+  IN CONST  EFI_GUID                         *VariableGuid,
+  OUT       UINT32                           *Attributes,
+  IN OUT    UINTN                            *DataSize,
+  OUT       VOID                             *Data OPTIONAL
+  );
+
+/**
+  Return the next variable name and GUID.
+
+  This function is called multiple times to retrieve the VariableName
+  and VariableGuid of all variables currently available in the system.
+  On each call, the previous results are passed into the interface,
+  and, on return, the interface returns the data for the next
+  interface. When the entire variable list has been returned,
+  EFI_NOT_FOUND is returned.
+
+  @param  This              A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
+
+  @param  VariableNameSize  On entry, points to the size of the buffer pointed to by VariableName.
+  @param  VariableName      On entry, a pointer to a null-terminated string that is the variable's name.
+                            On return, points to the next variable's null-terminated name string.
+
+  @param  VariableGuid      On entry, a pointer to an UEFI _GUID that is the variable's GUID.
+                            On return, a pointer to the next variable's GUID.
+
+  @retval EFI_SUCCESS           The variable was read successfully.
+  @retval EFI_NOT_FOUND         The variable could not be found.
+  @retval EFI_BUFFER_TOO_SMALL  The VariableNameSize is too small for the resulting
+                                data. VariableNameSize is updated with the size
+                                required for the specified variable.
+  @retval EFI_INVALID_PARAMETER VariableName, VariableGuid or
+                                VariableNameSize is NULL.
+  @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
+
+**/
+EFI_STATUS
+EFIAPI
+PeiGetNextVariableNameEx (
+  IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI  *This,
+  IN OUT UINTN                               *VariableNameSize,
+  IN OUT CHAR16                              *VariableName,
+  IN OUT EFI_GUID                            *VariableGuid
+  );
+
 #endif
diff --git a/MdeModulePkg/Universal/Variable/Pei/VariableParsing.h b/MdeModulePkg/Universal/Variable/Pei/VariableParsing.h
new file mode 100644
index 000000000000..d7af6cb6e8be
--- /dev/null
+++ b/MdeModulePkg/Universal/Variable/Pei/VariableParsing.h
@@ -0,0 +1,309 @@
+/** @file
+  The internal header file includes the common header files, defines
+  internal structure and functions used by PeiVariable module.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef PEI_VARIABLE_PARSING_H_
+#define PEI_VARIABLE_PARSING_H_
+
+#include "Variable.h"
+
+/**
+
+  Gets the pointer to the first variable header in given variable store area.
+
+  @param[in] VarStoreHeader  Pointer to the Variable Store Header.
+
+  @return Pointer to the first variable header.
+
+**/
+VARIABLE_HEADER *
+GetStartPointer (
+  IN VARIABLE_STORE_HEADER  *VarStoreHeader
+  );
+
+/**
+
+  Gets the pointer to the end of the variable storage area.
+
+  This function gets pointer to the end of the variable storage
+  area, according to the input variable store header.
+
+  @param[in] VarStoreHeader  Pointer to the Variable Store Header.
+
+  @return Pointer to the end of the variable storage area.
+
+**/
+VARIABLE_HEADER *
+GetEndPointer (
+  IN VARIABLE_STORE_HEADER  *VarStoreHeader
+  );
+
+/**
+  This code checks if variable header is valid or not.
+
+  @param[in]  Variable  Pointer to the Variable Header.
+
+  @retval TRUE      Variable header is valid.
+  @retval FALSE     Variable header is not valid.
+
+**/
+BOOLEAN
+IsValidVariableHeader (
+  IN  VARIABLE_HEADER  *Variable
+  );
+
+/**
+  This code gets the pointer to the next variable header.
+
+  @param[in]  StoreInfo         Pointer to variable store info structure.
+  @param[in]  Variable          Pointer to the Variable Header.
+  @param[in]  VariableHeader    Pointer to the Variable Header that has consecutive content.
+
+  @return  A VARIABLE_HEADER* pointer to next variable header.
+
+**/
+VARIABLE_HEADER *
+GetNextVariablePtr (
+  IN  VARIABLE_STORE_INFO  *StoreInfo,
+  IN  VARIABLE_HEADER      *Variable,
+  IN  VARIABLE_HEADER      *VariableHeader
+  );
+
+/**
+  This code gets the pointer to the variable guid.
+
+  @param[in]  Variable   Pointer to the Variable Header.
+  @param[in]  AuthFlag   Authenticated variable flag.
+
+  @return A EFI_GUID* pointer to Vendor Guid.
+
+**/
+EFI_GUID *
+GetVendorGuidPtr (
+  IN VARIABLE_HEADER  *Variable,
+  IN BOOLEAN          AuthFlag
+  );
+
+/**
+  This code gets the pointer to the variable name.
+
+  @param[in]   Variable  Pointer to the Variable Header.
+  @param[in]   AuthFlag  Authenticated variable flag.
+
+  @return  A CHAR16* pointer to Variable Name.
+
+**/
+CHAR16 *
+GetVariableNamePtr (
+  IN VARIABLE_HEADER  *Variable,
+  IN BOOLEAN          AuthFlag
+  );
+
+/**
+  This code gets the size of name of variable.
+
+  @param[in]  Variable  Pointer to the Variable Header.
+  @param[in]  AuthFlag  Authenticated variable flag.
+
+  @return Size of variable in bytes in type UINTN.
+
+**/
+UINTN
+NameSizeOfVariable (
+  IN  VARIABLE_HEADER  *Variable,
+  IN  BOOLEAN          AuthFlag
+  );
+
+/**
+  This code gets the size of data of variable.
+
+  @param[in]  Variable  Pointer to the Variable Header.
+  @param[in]  AuthFlag  Authenticated variable flag.
+
+  @return Size of variable in bytes in type UINTN.
+
+**/
+UINTN
+DataSizeOfVariable (
+  IN  VARIABLE_HEADER  *Variable,
+  IN  BOOLEAN          AuthFlag
+  );
+
+/**
+  This code gets the pointer to the variable data.
+
+  @param[in]   Variable         Pointer to the Variable Header.
+  @param[in]   VariableHeader   Pointer to the Variable Header that has consecutive content.
+  @param[in]   AuthFlag         Authenticated variable flag.
+
+  @return  A UINT8* pointer to Variable Data.
+
+**/
+UINT8 *
+GetVariableDataPtr (
+  IN  VARIABLE_HEADER  *Variable,
+  IN  VARIABLE_HEADER  *VariableHeader,
+  IN  BOOLEAN          AuthFlag
+  );
+
+/**
+  Get variable header that has consecutive content.
+
+  @param[in]  StoreInfo      Pointer to variable store info structure.
+  @param[in]  Variable       Pointer to the Variable Header.
+  @param[out] VariableHeader Pointer to Pointer to the Variable Header that has consecutive content.
+
+  @retval TRUE          Variable header is valid.
+  @retval FALSE         Variable header is not valid.
+
+**/
+BOOLEAN
+GetVariableHeader (
+  IN VARIABLE_STORE_INFO  *StoreInfo,
+  IN VARIABLE_HEADER      *Variable,
+  OUT VARIABLE_HEADER     **VariableHeader
+  );
+
+/**
+  This code gets the size of variable header.
+
+  @param[in] AuthFlag   Authenticated variable flag.
+
+  @return Size of variable header in bytes in type UINTN.
+
+**/
+UINTN
+GetVariableHeaderSize (
+  IN  BOOLEAN  AuthFlag
+  );
+
+/**
+  Get variable name or data to output buffer.
+
+  @param[in]  StoreInfo     Pointer to variable store info structure.
+  @param[in]  NameOrData    Pointer to the variable name/data that may be inconsecutive.
+  @param[in]  Size          Variable name/data size.
+  @param[out] Buffer        Pointer to output buffer to hold the variable name/data.
+
+**/
+VOID
+GetVariableNameOrData (
+  IN VARIABLE_STORE_INFO  *StoreInfo,
+  IN UINT8                *NameOrData,
+  IN UINTN                Size,
+  OUT UINT8               *Buffer
+  );
+
+/**
+  This function compares a variable with variable entries in database.
+
+  @param[in]  StoreInfo     Pointer to variable store info structure.
+  @param[in]  Variable      Pointer to the variable in our database
+  @param[in]  VariableHeader Pointer to the Variable Header that has consecutive content.
+  @param[in]  VariableName  Name of the variable to compare to 'Variable'
+  @param[in]  VendorGuid    GUID of the variable to compare to 'Variable'
+  @param[out] PtrTrack      Variable Track Pointer structure that contains Variable Information.
+
+  @retval EFI_SUCCESS    Found match variable
+  @retval EFI_NOT_FOUND  Variable not found
+
+**/
+EFI_STATUS
+CompareWithValidVariable (
+  IN  VARIABLE_STORE_INFO     *StoreInfo,
+  IN  VARIABLE_HEADER         *Variable,
+  IN  VARIABLE_HEADER         *VariableHeader,
+  IN  CONST CHAR16            *VariableName,
+  IN  CONST EFI_GUID          *VendorGuid,
+  OUT VARIABLE_POINTER_TRACK  *PtrTrack
+  );
+
+/**
+
+  Retrieve details of the variable next to given variable within VariableStore.
+
+  If VarInfo->Address is NULL, the first one in VariableStore is returned.
+
+  VariableStart and/or VariableEnd can be given optionally for the situation
+  in which the valid storage space is smaller than the VariableStore->Size.
+  This usually happens when PEI variable services make a compact variable
+  cache to save memory, which cannot make use VariableStore->Size to determine
+  the correct variable storage range.
+
+  @param[in,out] VariableInfo             Pointer to variable information.
+
+  @retval EFI_INVALID_PARAMETER  VariableInfo or VariableStore is NULL.
+  @retval EFI_NOT_FOUND          If the end of VariableStore is reached.
+  @retval EFI_SUCCESS            The next variable is retrieved successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+GetNextVariableInfo (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VariableInfo
+  );
+
+/**
+
+  Retrieve details about a variable and return them in VariableInfo->Header.
+
+  If VariableInfo->Address is given, this function will calculate its offset
+  relative to given variable storage via VariableStore; Otherwise, it will try
+  other internal variable storages or cached copies. It's assumed that, for all
+  copies of NV variable storage, all variables are stored in the same relative
+  position. If VariableInfo->Address is found in the range of any storage copies,
+  its offset relative to that storage should be the same in other copies.
+
+  If VariableInfo->Offset is given (non-zero) but not VariableInfo->Address,
+  this function will return the variable memory address inside VariableStore,
+  if given, via VariableInfo->Address; Otherwise, the address of other storage
+  copies will be returned, if any.
+
+  For a new variable whose offset has not been determined, a value of -1 as
+  VariableInfo->Offset should be passed to skip the offset calculation.
+
+  @param[in,out] VariableInfo             Pointer to variable information.
+
+  @retval EFI_INVALID_PARAMETER  VariableInfo is NULL or both VariableInfo->Address
+                                 and VariableInfo->Offset are NULL (0).
+  @retval EFI_NOT_FOUND          If given Address or Offset is out of range of
+                                 any given or internal storage copies.
+  @retval EFI_SUCCESS            Variable details are retrieved successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+GetVariableInfo (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VariableInfo
+  );
+
+/**
+
+  Find variable specified with input parameters.
+
+  @param[in] StoreInfo             Pointer to variable information.
+  @param[in] VariableName          Pointer to variable name.
+  @param[in] VendorGuid            Pointer to variable GUID.
+  @param[in] PtrTrack              Pointer to variable track.
+
+  @retval EFI_INVALID_PARAMETER  VariableInfo is NULL or both VariableInfo->Address
+                                 and VariableInfo->Offset are NULL (0).
+  @retval EFI_NOT_FOUND          If given Address or Offset is out of range of
+                                 any given or internal storage copies.
+  @retval EFI_SUCCESS            Variable details are retrieved successfully.
+
+**/
+EFI_STATUS
+FindVariableEx (
+  IN VARIABLE_STORE_INFO      *StoreInfo,
+  IN CONST CHAR16             *VariableName,
+  IN CONST EFI_GUID           *VendorGuid,
+  OUT VARIABLE_POINTER_TRACK  *PtrTrack
+  );
+
+#endif
diff --git a/MdeModulePkg/Universal/Variable/Pei/VariableStore.h b/MdeModulePkg/Universal/Variable/Pei/VariableStore.h
new file mode 100644
index 000000000000..6e2f6f939bab
--- /dev/null
+++ b/MdeModulePkg/Universal/Variable/Pei/VariableStore.h
@@ -0,0 +1,116 @@
+/** @file
+  Implement ReadOnly Variable Services required by PEIM and install
+  PEI ReadOnly Varaiable2 PPI. These services operates the non volatile storage space.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef PEI_VARIABLE_STORE_H_
+#define PEI_VARIABLE_STORE_H_
+
+/**
+  Get variable store status.
+
+  @param[in]  VarStoreHeader  Pointer to the Variable Store Header.
+
+  @retval  EfiRaw      Variable store is raw
+  @retval  EfiValid    Variable store is valid
+  @retval  EfiInvalid  Variable store is invalid
+
+**/
+VARIABLE_STORE_STATUS
+GetVariableStoreStatus (
+  IN VARIABLE_STORE_HEADER  *VarStoreHeader
+  );
+
+/**
+  Reports HOB variable store is available or not.
+
+  @retval EFI_NOT_READY  HOB variable store info not available.
+  @retval EFI_NOT_FOUND  HOB variable store is NOT available.
+  @retval EFI_SUCCESS    HOB variable store is available.
+**/
+EFI_STATUS
+EFIAPI
+IsHobVariableStoreAvailable (
+  VOID
+  );
+
+/**
+  Get HOB variable store.
+
+  @param[out] StoreInfo             Return the store info.
+
+**/
+VOID
+GetHobVariableStore (
+  OUT VARIABLE_STORE_INFO  *StoreInfo
+  );
+
+/**
+  Get NV variable store.
+
+  @param[out] StoreInfo             Return the store info.
+  @param[out] VariableStoreHeader   Return header of FV containing the store.
+
+**/
+VOID
+GetNvVariableStore (
+  OUT VARIABLE_STORE_INFO         *StoreInfo,
+  OUT EFI_FIRMWARE_VOLUME_HEADER  **VariableFvHeader
+  );
+
+/**
+  Return the variable store header and the store info based on the Index.
+
+  @param[in]  Type       The type of the variable store.
+  @param[out] StoreInfo  Return the store info.
+
+  @return  Pointer to the variable store header.
+**/
+VARIABLE_STORE_HEADER *
+GetVariableStore (
+  IN VARIABLE_STORE_TYPE   Type,
+  OUT VARIABLE_STORE_INFO  *StoreInfo
+  );
+
+/**
+  Make a cached copy of NV variable storage.
+
+  To save memory in PEI phase, only valid variables are copied into cache.
+  An IndexTable could be used to store the offset (relative to NV storage
+  base) of each copied variable, in case we need to restore the storage
+  as the same (valid) variables layout as in original one.
+
+  Variables with valid format and following state can be taken as valid:
+    - with state VAR_ADDED;
+    - with state VAR_IN_DELETED_TRANSITION but without the same variable
+      with state VAR_ADDED;
+    - with state VAR_ADDED and/or VAR_IN_DELETED_TRANSITION for variable
+      MetaDataHmacVar.
+
+  @param[out]     StoreCacheBase    Base address of variable storage cache.
+  @param[in,out]  StoreCacheSize    Size of space in StoreCacheBase.
+  @param[out]     IndexTable        Buffer of index (offset) table with entries of
+                                    VariableNumber.
+  @param[out]     VariableNumber    Number of valid variables.
+  @param[out]     AuthFlag          Aut-variable indicator.
+
+  @return EFI_INVALID_PARAMETER Invalid StoreCacheSize and/or StoreCacheBase.
+  @return EFI_VOLUME_CORRUPTED  Invalid or no NV variable storage found.
+  @return EFI_BUFFER_TOO_SMALL  StoreCacheSize is smaller than needed.
+  @return EFI_SUCCESS           NV variable storage is cached successfully.
+**/
+EFI_STATUS
+EFIAPI
+InitNvVariableStore (
+  OUT  EFI_PHYSICAL_ADDRESS  StoreCacheBase OPTIONAL,
+  IN OUT  UINT32             *StoreCacheSize,
+  OUT  UINT32                *IndexTable OPTIONAL,
+  OUT  UINT32                *VariableNumber OPTIONAL,
+  OUT  BOOLEAN               *AuthFlag OPTIONAL
+  );
+
+#endif
diff --git a/MdeModulePkg/Universal/Variable/Pei/Variable.c b/MdeModulePkg/Universal/Variable/Pei/Variable.c
index b36dd0de67b2..ce790946626e 100644
--- a/MdeModulePkg/Universal/Variable/Pei/Variable.c
+++ b/MdeModulePkg/Universal/Variable/Pei/Variable.c
@@ -2,20 +2,22 @@
   Implement ReadOnly Variable Services required by PEIM and install
   PEI ReadOnly Varaiable2 PPI. These services operates the non volatile storage space.
 
-Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
 Copyright (c) Microsoft Corporation.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
 #include "Variable.h"
+#include "VariableParsing.h"
+#include "VariableStore.h"
 
 //
 // Module globals
 //
 EFI_PEI_READ_ONLY_VARIABLE2_PPI  mVariablePpi = {
-  PeiGetVariable,
-  PeiGetNextVariableName
+  PeiGetVariableEx,
+  PeiGetNextVariableNameEx
 };
 
 EFI_PEI_PPI_DESCRIPTOR  mPpiListVariable = {
@@ -41,759 +43,33 @@ PeimInitializeVariableServices (
   IN CONST EFI_PEI_SERVICES     **PeiServices
   )
 {
+  EFI_STATUS                     Status;
+  PROTECTED_VARIABLE_CONTEXT_IN  ContextIn;
+
+  //
+  // If protected variable services are not supported, EFI_UNSUPPORTED should
+  // be always returned. Check it here.
+  //
+  ContextIn.StructVersion = PROTECTED_VARIABLE_CONTEXT_IN_STRUCT_VERSION;
+  ContextIn.StructSize    = sizeof (ContextIn);
+
+  ContextIn.MaxVariableSize             = 0;
+  ContextIn.VariableServiceUser         = FromPeiModule;
+  ContextIn.GetVariableInfo             = GetVariableInfo;
+  ContextIn.GetNextVariableInfo         = GetNextVariableInfo;
+  ContextIn.FindVariableSmm             = NULL;
+  ContextIn.UpdateVariableStore         = NULL;
+  ContextIn.UpdateVariable              = NULL;
+  ContextIn.IsHobVariableStoreAvailable = IsHobVariableStoreAvailable;
+
+  Status = ProtectedVariableLibInitialize (&ContextIn);
+  if (EFI_ERROR (Status) && (Status != EFI_UNSUPPORTED)) {
+    return Status;
+  }
+
   return PeiServicesInstallPpi (&mPpiListVariable);
 }
 
-/**
-
-  Gets the pointer to the first variable header in given variable store area.
-
-  @param VarStoreHeader  Pointer to the Variable Store Header.
-
-  @return Pointer to the first variable header.
-
-**/
-VARIABLE_HEADER *
-GetStartPointer (
-  IN VARIABLE_STORE_HEADER  *VarStoreHeader
-  )
-{
-  //
-  // The start of variable store
-  //
-  return (VARIABLE_HEADER *)HEADER_ALIGN (VarStoreHeader + 1);
-}
-
-/**
-
-  Gets the pointer to the end of the variable storage area.
-
-  This function gets pointer to the end of the variable storage
-  area, according to the input variable store header.
-
-  @param VarStoreHeader  Pointer to the Variable Store Header.
-
-  @return Pointer to the end of the variable storage area.
-
-**/
-VARIABLE_HEADER *
-GetEndPointer (
-  IN VARIABLE_STORE_HEADER  *VarStoreHeader
-  )
-{
-  //
-  // The end of variable store
-  //
-  return (VARIABLE_HEADER *)HEADER_ALIGN ((UINTN)VarStoreHeader + VarStoreHeader->Size);
-}
-
-/**
-  This code checks if variable header is valid or not.
-
-  @param  Variable  Pointer to the Variable Header.
-
-  @retval TRUE      Variable header is valid.
-  @retval FALSE     Variable header is not valid.
-
-**/
-BOOLEAN
-IsValidVariableHeader (
-  IN  VARIABLE_HEADER  *Variable
-  )
-{
-  if ((Variable == NULL) || (Variable->StartId != VARIABLE_DATA)) {
-    return FALSE;
-  }
-
-  return TRUE;
-}
-
-/**
-  This code gets the size of variable header.
-
-  @param AuthFlag   Authenticated variable flag.
-
-  @return Size of variable header in bytes in type UINTN.
-
-**/
-UINTN
-GetVariableHeaderSize (
-  IN  BOOLEAN  AuthFlag
-  )
-{
-  UINTN  Value;
-
-  if (AuthFlag) {
-    Value = sizeof (AUTHENTICATED_VARIABLE_HEADER);
-  } else {
-    Value = sizeof (VARIABLE_HEADER);
-  }
-
-  return Value;
-}
-
-/**
-  This code gets the size of name of variable.
-
-  @param  Variable  Pointer to the Variable Header.
-  @param  AuthFlag  Authenticated variable flag.
-
-  @return Size of variable in bytes in type UINTN.
-
-**/
-UINTN
-NameSizeOfVariable (
-  IN  VARIABLE_HEADER  *Variable,
-  IN  BOOLEAN          AuthFlag
-  )
-{
-  AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
-
-  AuthVariable = (AUTHENTICATED_VARIABLE_HEADER *)Variable;
-  if (AuthFlag) {
-    if ((AuthVariable->State == (UINT8)(-1)) ||
-        (AuthVariable->DataSize == (UINT32)(-1)) ||
-        (AuthVariable->NameSize == (UINT32)(-1)) ||
-        (AuthVariable->Attributes == (UINT32)(-1)))
-    {
-      return 0;
-    }
-
-    return (UINTN)AuthVariable->NameSize;
-  } else {
-    if ((Variable->State == (UINT8)(-1)) ||
-        (Variable->DataSize == (UINT32)(-1)) ||
-        (Variable->NameSize == (UINT32)(-1)) ||
-        (Variable->Attributes == (UINT32)(-1)))
-    {
-      return 0;
-    }
-
-    return (UINTN)Variable->NameSize;
-  }
-}
-
-/**
-  This code gets the size of data of variable.
-
-  @param  Variable  Pointer to the Variable Header.
-  @param  AuthFlag  Authenticated variable flag.
-
-  @return Size of variable in bytes in type UINTN.
-
-**/
-UINTN
-DataSizeOfVariable (
-  IN  VARIABLE_HEADER  *Variable,
-  IN  BOOLEAN          AuthFlag
-  )
-{
-  AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
-
-  AuthVariable = (AUTHENTICATED_VARIABLE_HEADER *)Variable;
-  if (AuthFlag) {
-    if ((AuthVariable->State == (UINT8)(-1)) ||
-        (AuthVariable->DataSize == (UINT32)(-1)) ||
-        (AuthVariable->NameSize == (UINT32)(-1)) ||
-        (AuthVariable->Attributes == (UINT32)(-1)))
-    {
-      return 0;
-    }
-
-    return (UINTN)AuthVariable->DataSize;
-  } else {
-    if ((Variable->State == (UINT8)(-1)) ||
-        (Variable->DataSize == (UINT32)(-1)) ||
-        (Variable->NameSize == (UINT32)(-1)) ||
-        (Variable->Attributes == (UINT32)(-1)))
-    {
-      return 0;
-    }
-
-    return (UINTN)Variable->DataSize;
-  }
-}
-
-/**
-  This code gets the pointer to the variable name.
-
-  @param   Variable  Pointer to the Variable Header.
-  @param   AuthFlag  Authenticated variable flag.
-
-  @return  A CHAR16* pointer to Variable Name.
-
-**/
-CHAR16 *
-GetVariableNamePtr (
-  IN VARIABLE_HEADER  *Variable,
-  IN BOOLEAN          AuthFlag
-  )
-{
-  return (CHAR16 *)((UINTN)Variable + GetVariableHeaderSize (AuthFlag));
-}
-
-/**
-  This code gets the pointer to the variable guid.
-
-  @param Variable   Pointer to the Variable Header.
-  @param AuthFlag   Authenticated variable flag.
-
-  @return A EFI_GUID* pointer to Vendor Guid.
-
-**/
-EFI_GUID *
-GetVendorGuidPtr (
-  IN VARIABLE_HEADER  *Variable,
-  IN BOOLEAN          AuthFlag
-  )
-{
-  AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
-
-  AuthVariable = (AUTHENTICATED_VARIABLE_HEADER *)Variable;
-  if (AuthFlag) {
-    return &AuthVariable->VendorGuid;
-  } else {
-    return &Variable->VendorGuid;
-  }
-}
-
-/**
-  This code gets the pointer to the variable data.
-
-  @param   Variable         Pointer to the Variable Header.
-  @param   VariableHeader   Pointer to the Variable Header that has consecutive content.
-  @param   AuthFlag         Authenticated variable flag.
-
-  @return  A UINT8* pointer to Variable Data.
-
-**/
-UINT8 *
-GetVariableDataPtr (
-  IN  VARIABLE_HEADER  *Variable,
-  IN  VARIABLE_HEADER  *VariableHeader,
-  IN  BOOLEAN          AuthFlag
-  )
-{
-  UINTN  Value;
-
-  //
-  // Be careful about pad size for alignment
-  //
-  Value  =  (UINTN)GetVariableNamePtr (Variable, AuthFlag);
-  Value += NameSizeOfVariable (VariableHeader, AuthFlag);
-  Value += GET_PAD_SIZE (NameSizeOfVariable (VariableHeader, AuthFlag));
-
-  return (UINT8 *)Value;
-}
-
-/**
-  This code gets the pointer to the next variable header.
-
-  @param  StoreInfo         Pointer to variable store info structure.
-  @param  Variable          Pointer to the Variable Header.
-  @param  VariableHeader    Pointer to the Variable Header that has consecutive content.
-
-  @return  A VARIABLE_HEADER* pointer to next variable header.
-
-**/
-VARIABLE_HEADER *
-GetNextVariablePtr (
-  IN  VARIABLE_STORE_INFO  *StoreInfo,
-  IN  VARIABLE_HEADER      *Variable,
-  IN  VARIABLE_HEADER      *VariableHeader
-  )
-{
-  EFI_PHYSICAL_ADDRESS  TargetAddress;
-  EFI_PHYSICAL_ADDRESS  SpareAddress;
-  UINTN                 Value;
-
-  Value  =  (UINTN)GetVariableDataPtr (Variable, VariableHeader, StoreInfo->AuthFlag);
-  Value += DataSizeOfVariable (VariableHeader, StoreInfo->AuthFlag);
-  Value += GET_PAD_SIZE (DataSizeOfVariable (VariableHeader, StoreInfo->AuthFlag));
-  //
-  // Be careful about pad size for alignment
-  //
-  Value = HEADER_ALIGN (Value);
-
-  if (StoreInfo->FtwLastWriteData != NULL) {
-    TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
-    SpareAddress  = StoreInfo->FtwLastWriteData->SpareAddress;
-    if (((UINTN)Variable < (UINTN)TargetAddress) && (Value >= (UINTN)TargetAddress)) {
-      //
-      // Next variable is in spare block.
-      //
-      Value = (UINTN)SpareAddress + (Value - (UINTN)TargetAddress);
-    }
-  }
-
-  return (VARIABLE_HEADER *)Value;
-}
-
-/**
-  Get variable store status.
-
-  @param  VarStoreHeader  Pointer to the Variable Store Header.
-
-  @retval  EfiRaw      Variable store is raw
-  @retval  EfiValid    Variable store is valid
-  @retval  EfiInvalid  Variable store is invalid
-
-**/
-VARIABLE_STORE_STATUS
-GetVariableStoreStatus (
-  IN VARIABLE_STORE_HEADER  *VarStoreHeader
-  )
-{
-  if ((CompareGuid (&VarStoreHeader->Signature, &gEfiAuthenticatedVariableGuid) ||
-       CompareGuid (&VarStoreHeader->Signature, &gEfiVariableGuid)) &&
-      (VarStoreHeader->Format == VARIABLE_STORE_FORMATTED) &&
-      (VarStoreHeader->State == VARIABLE_STORE_HEALTHY)
-      )
-  {
-    return EfiValid;
-  }
-
-  if ((((UINT32 *)(&VarStoreHeader->Signature))[0] == 0xffffffff) &&
-      (((UINT32 *)(&VarStoreHeader->Signature))[1] == 0xffffffff) &&
-      (((UINT32 *)(&VarStoreHeader->Signature))[2] == 0xffffffff) &&
-      (((UINT32 *)(&VarStoreHeader->Signature))[3] == 0xffffffff) &&
-      (VarStoreHeader->Size == 0xffffffff) &&
-      (VarStoreHeader->Format == 0xff) &&
-      (VarStoreHeader->State == 0xff)
-      )
-  {
-    return EfiRaw;
-  } else {
-    return EfiInvalid;
-  }
-}
-
-/**
-  Compare two variable names, one of them may be inconsecutive.
-
-  @param StoreInfo      Pointer to variable store info structure.
-  @param Name1          Pointer to one variable name.
-  @param Name2          Pointer to another variable name.
-  @param NameSize       Variable name size.
-
-  @retval TRUE          Name1 and Name2 are identical.
-  @retval FALSE         Name1 and Name2 are not identical.
-
-**/
-BOOLEAN
-CompareVariableName (
-  IN VARIABLE_STORE_INFO  *StoreInfo,
-  IN CONST CHAR16         *Name1,
-  IN CONST CHAR16         *Name2,
-  IN UINTN                NameSize
-  )
-{
-  EFI_PHYSICAL_ADDRESS  TargetAddress;
-  EFI_PHYSICAL_ADDRESS  SpareAddress;
-  UINTN                 PartialNameSize;
-
-  if (StoreInfo->FtwLastWriteData != NULL) {
-    TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
-    SpareAddress  = StoreInfo->FtwLastWriteData->SpareAddress;
-    if (((UINTN)Name1 < (UINTN)TargetAddress) && (((UINTN)Name1 + NameSize) > (UINTN)TargetAddress)) {
-      //
-      // Name1 is inconsecutive.
-      //
-      PartialNameSize = (UINTN)TargetAddress - (UINTN)Name1;
-      //
-      // Partial content is in NV storage.
-      //
-      if (CompareMem ((UINT8 *)Name1, (UINT8 *)Name2, PartialNameSize) == 0) {
-        //
-        // Another partial content is in spare block.
-        //
-        if (CompareMem ((UINT8 *)(UINTN)SpareAddress, (UINT8 *)Name2 + PartialNameSize, NameSize - PartialNameSize) == 0) {
-          return TRUE;
-        }
-      }
-
-      return FALSE;
-    } else if (((UINTN)Name2 < (UINTN)TargetAddress) && (((UINTN)Name2 + NameSize) > (UINTN)TargetAddress)) {
-      //
-      // Name2 is inconsecutive.
-      //
-      PartialNameSize = (UINTN)TargetAddress - (UINTN)Name2;
-      //
-      // Partial content is in NV storage.
-      //
-      if (CompareMem ((UINT8 *)Name2, (UINT8 *)Name1, PartialNameSize) == 0) {
-        //
-        // Another partial content is in spare block.
-        //
-        if (CompareMem ((UINT8 *)(UINTN)SpareAddress, (UINT8 *)Name1 + PartialNameSize, NameSize - PartialNameSize) == 0) {
-          return TRUE;
-        }
-      }
-
-      return FALSE;
-    }
-  }
-
-  //
-  // Both Name1 and Name2 are consecutive.
-  //
-  if (CompareMem ((UINT8 *)Name1, (UINT8 *)Name2, NameSize) == 0) {
-    return TRUE;
-  }
-
-  return FALSE;
-}
-
-/**
-  This function compares a variable with variable entries in database.
-
-  @param  StoreInfo     Pointer to variable store info structure.
-  @param  Variable      Pointer to the variable in our database
-  @param  VariableHeader Pointer to the Variable Header that has consecutive content.
-  @param  VariableName  Name of the variable to compare to 'Variable'
-  @param  VendorGuid    GUID of the variable to compare to 'Variable'
-  @param  PtrTrack      Variable Track Pointer structure that contains Variable Information.
-
-  @retval EFI_SUCCESS    Found match variable
-  @retval EFI_NOT_FOUND  Variable not found
-
-**/
-EFI_STATUS
-CompareWithValidVariable (
-  IN  VARIABLE_STORE_INFO     *StoreInfo,
-  IN  VARIABLE_HEADER         *Variable,
-  IN  VARIABLE_HEADER         *VariableHeader,
-  IN  CONST CHAR16            *VariableName,
-  IN  CONST EFI_GUID          *VendorGuid,
-  OUT VARIABLE_POINTER_TRACK  *PtrTrack
-  )
-{
-  VOID      *Point;
-  EFI_GUID  *TempVendorGuid;
-
-  TempVendorGuid = GetVendorGuidPtr (VariableHeader, StoreInfo->AuthFlag);
-
-  if (VariableName[0] == 0) {
-    PtrTrack->CurrPtr = Variable;
-    return EFI_SUCCESS;
-  } else {
-    //
-    // Don't use CompareGuid function here for performance reasons.
-    // Instead we compare the GUID a UINT32 at a time and branch
-    // on the first failed comparison.
-    //
-    if ((((INT32 *)VendorGuid)[0] == ((INT32 *)TempVendorGuid)[0]) &&
-        (((INT32 *)VendorGuid)[1] == ((INT32 *)TempVendorGuid)[1]) &&
-        (((INT32 *)VendorGuid)[2] == ((INT32 *)TempVendorGuid)[2]) &&
-        (((INT32 *)VendorGuid)[3] == ((INT32 *)TempVendorGuid)[3])
-        )
-    {
-      ASSERT (NameSizeOfVariable (VariableHeader, StoreInfo->AuthFlag) != 0);
-      Point = (VOID *)GetVariableNamePtr (Variable, StoreInfo->AuthFlag);
-      if (CompareVariableName (StoreInfo, VariableName, Point, NameSizeOfVariable (VariableHeader, StoreInfo->AuthFlag))) {
-        PtrTrack->CurrPtr = Variable;
-        return EFI_SUCCESS;
-      }
-    }
-  }
-
-  return EFI_NOT_FOUND;
-}
-
-/**
-  Get HOB variable store.
-
-  @param[out] StoreInfo             Return the store info.
-  @param[out] VariableStoreHeader   Return variable store header.
-
-**/
-VOID
-GetHobVariableStore (
-  OUT VARIABLE_STORE_INFO    *StoreInfo,
-  OUT VARIABLE_STORE_HEADER  **VariableStoreHeader
-  )
-{
-  EFI_HOB_GUID_TYPE  *GuidHob;
-
-  //
-  // Make sure there is no more than one Variable HOB.
-  //
-  DEBUG_CODE_BEGIN ();
-  GuidHob = GetFirstGuidHob (&gEfiAuthenticatedVariableGuid);
-  if (GuidHob != NULL) {
-    if ((GetNextGuidHob (&gEfiAuthenticatedVariableGuid, GET_NEXT_HOB (GuidHob)) != NULL)) {
-      DEBUG ((DEBUG_ERROR, "ERROR: Found two Auth Variable HOBs\n"));
-      ASSERT (FALSE);
-    } else if (GetFirstGuidHob (&gEfiVariableGuid) != NULL) {
-      DEBUG ((DEBUG_ERROR, "ERROR: Found one Auth + one Normal Variable HOBs\n"));
-      ASSERT (FALSE);
-    }
-  } else {
-    GuidHob = GetFirstGuidHob (&gEfiVariableGuid);
-    if (GuidHob != NULL) {
-      if ((GetNextGuidHob (&gEfiVariableGuid, GET_NEXT_HOB (GuidHob)) != NULL)) {
-        DEBUG ((DEBUG_ERROR, "ERROR: Found two Normal Variable HOBs\n"));
-        ASSERT (FALSE);
-      }
-    }
-  }
-
-  DEBUG_CODE_END ();
-
-  GuidHob = GetFirstGuidHob (&gEfiAuthenticatedVariableGuid);
-  if (GuidHob != NULL) {
-    *VariableStoreHeader = (VARIABLE_STORE_HEADER *)GET_GUID_HOB_DATA (GuidHob);
-    StoreInfo->AuthFlag  = TRUE;
-  } else {
-    GuidHob = GetFirstGuidHob (&gEfiVariableGuid);
-    if (GuidHob != NULL) {
-      *VariableStoreHeader = (VARIABLE_STORE_HEADER *)GET_GUID_HOB_DATA (GuidHob);
-      StoreInfo->AuthFlag  = FALSE;
-    }
-  }
-}
-
-/**
-  Return the variable store header and the store info based on the Index.
-
-  @param Type       The type of the variable store.
-  @param StoreInfo  Return the store info.
-
-  @return  Pointer to the variable store header.
-**/
-VARIABLE_STORE_HEADER *
-GetVariableStore (
-  IN VARIABLE_STORE_TYPE   Type,
-  OUT VARIABLE_STORE_INFO  *StoreInfo
-  )
-{
-  EFI_HOB_GUID_TYPE                     *GuidHob;
-  EFI_FIRMWARE_VOLUME_HEADER            *FvHeader;
-  VARIABLE_STORE_HEADER                 *VariableStoreHeader;
-  EFI_PHYSICAL_ADDRESS                  NvStorageBase;
-  UINT32                                NvStorageSize;
-  FAULT_TOLERANT_WRITE_LAST_WRITE_DATA  *FtwLastWriteData;
-  UINT32                                BackUpOffset;
-
-  StoreInfo->IndexTable       = NULL;
-  StoreInfo->FtwLastWriteData = NULL;
-  StoreInfo->AuthFlag         = FALSE;
-  VariableStoreHeader         = NULL;
-  switch (Type) {
-    case VariableStoreTypeHob:
-      GetHobVariableStore (StoreInfo, &VariableStoreHeader);
-
-      break;
-
-    case VariableStoreTypeNv:
-      if (!PcdGetBool (PcdEmuVariableNvModeEnable)) {
-        //
-        // Emulated non-volatile variable mode is not enabled.
-        //
-
-        NvStorageSize = PcdGet32 (PcdFlashNvStorageVariableSize);
-        NvStorageBase = (EFI_PHYSICAL_ADDRESS)(PcdGet64 (PcdFlashNvStorageVariableBase64) != 0 ?
-                                               PcdGet64 (PcdFlashNvStorageVariableBase64) :
-                                               PcdGet32 (PcdFlashNvStorageVariableBase)
-                                               );
-        ASSERT (NvStorageBase != 0);
-
-        //
-        // First let FvHeader point to NV storage base.
-        //
-        FvHeader = (EFI_FIRMWARE_VOLUME_HEADER *)(UINTN)NvStorageBase;
-
-        //
-        // Check the FTW last write data hob.
-        //
-        BackUpOffset = 0;
-        GuidHob      = GetFirstGuidHob (&gEdkiiFaultTolerantWriteGuid);
-        if (GuidHob != NULL) {
-          FtwLastWriteData = (FAULT_TOLERANT_WRITE_LAST_WRITE_DATA *)GET_GUID_HOB_DATA (GuidHob);
-          if (FtwLastWriteData->TargetAddress == NvStorageBase) {
-            //
-            // Let FvHeader point to spare block.
-            //
-            FvHeader = (EFI_FIRMWARE_VOLUME_HEADER *)(UINTN)FtwLastWriteData->SpareAddress;
-            DEBUG ((DEBUG_INFO, "PeiVariable: NV storage is backed up in spare block: 0x%x\n", (UINTN)FtwLastWriteData->SpareAddress));
-          } else if ((FtwLastWriteData->TargetAddress > NvStorageBase) && (FtwLastWriteData->TargetAddress < (NvStorageBase + NvStorageSize))) {
-            StoreInfo->FtwLastWriteData = FtwLastWriteData;
-            //
-            // Flash NV storage from the offset is backed up in spare block.
-            //
-            BackUpOffset = (UINT32)(FtwLastWriteData->TargetAddress - NvStorageBase);
-            DEBUG ((DEBUG_INFO, "PeiVariable: High partial NV storage from offset: %x is backed up in spare block: 0x%x\n", BackUpOffset, (UINTN)FtwLastWriteData->SpareAddress));
-            //
-            // At least one block data in flash NV storage is still valid, so still leave FvHeader point to NV storage base.
-            //
-          }
-        }
-
-        //
-        // Check if the Firmware Volume is not corrupted
-        //
-        if ((FvHeader->Signature != EFI_FVH_SIGNATURE) || (!CompareGuid (&gEfiSystemNvDataFvGuid, &FvHeader->FileSystemGuid))) {
-          DEBUG ((DEBUG_ERROR, "Firmware Volume for Variable Store is corrupted\n"));
-          break;
-        }
-
-        VariableStoreHeader = (VARIABLE_STORE_HEADER *)((UINT8 *)FvHeader + FvHeader->HeaderLength);
-
-        StoreInfo->AuthFlag = (BOOLEAN)(CompareGuid (&VariableStoreHeader->Signature, &gEfiAuthenticatedVariableGuid));
-
-        GuidHob = GetFirstGuidHob (&gEfiVariableIndexTableGuid);
-        if (GuidHob != NULL) {
-          StoreInfo->IndexTable = GET_GUID_HOB_DATA (GuidHob);
-        } else {
-          //
-          // If it's the first time to access variable region in flash, create a guid hob to record
-          // VAR_ADDED type variable info.
-          // Note that as the resource of PEI phase is limited, only store the limited number of
-          // VAR_ADDED type variables to reduce access time.
-          //
-          StoreInfo->IndexTable              = (VARIABLE_INDEX_TABLE *)BuildGuidHob (&gEfiVariableIndexTableGuid, sizeof (VARIABLE_INDEX_TABLE));
-          StoreInfo->IndexTable->Length      = 0;
-          StoreInfo->IndexTable->StartPtr    = GetStartPointer (VariableStoreHeader);
-          StoreInfo->IndexTable->EndPtr      = GetEndPointer (VariableStoreHeader);
-          StoreInfo->IndexTable->GoneThrough = 0;
-        }
-      }
-
-      break;
-
-    default:
-      ASSERT (FALSE);
-      break;
-  }
-
-  StoreInfo->VariableStoreHeader = VariableStoreHeader;
-  return VariableStoreHeader;
-}
-
-/**
-  Get variable header that has consecutive content.
-
-  @param StoreInfo      Pointer to variable store info structure.
-  @param Variable       Pointer to the Variable Header.
-  @param VariableHeader Pointer to Pointer to the Variable Header that has consecutive content.
-
-  @retval TRUE          Variable header is valid.
-  @retval FALSE         Variable header is not valid.
-
-**/
-BOOLEAN
-GetVariableHeader (
-  IN VARIABLE_STORE_INFO  *StoreInfo,
-  IN VARIABLE_HEADER      *Variable,
-  OUT VARIABLE_HEADER     **VariableHeader
-  )
-{
-  EFI_PHYSICAL_ADDRESS  TargetAddress;
-  EFI_PHYSICAL_ADDRESS  SpareAddress;
-  EFI_HOB_GUID_TYPE     *GuidHob;
-  UINTN                 PartialHeaderSize;
-
-  if (Variable == NULL) {
-    return FALSE;
-  }
-
-  //
-  // First assume variable header pointed by Variable is consecutive.
-  //
-  *VariableHeader = Variable;
-
-  if (StoreInfo->FtwLastWriteData != NULL) {
-    TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
-    SpareAddress  = StoreInfo->FtwLastWriteData->SpareAddress;
-    if (((UINTN)Variable > (UINTN)SpareAddress) &&
-        (((UINTN)Variable - (UINTN)SpareAddress + (UINTN)TargetAddress) >= (UINTN)GetEndPointer (StoreInfo->VariableStoreHeader)))
-    {
-      //
-      // Reach the end of variable store.
-      //
-      return FALSE;
-    }
-
-    if (((UINTN)Variable < (UINTN)TargetAddress) && (((UINTN)Variable + GetVariableHeaderSize (StoreInfo->AuthFlag)) > (UINTN)TargetAddress)) {
-      //
-      // Variable header pointed by Variable is inconsecutive,
-      // create a guid hob to combine the two partial variable header content together.
-      //
-      GuidHob = GetFirstGuidHob (&gEfiCallerIdGuid);
-      if (GuidHob != NULL) {
-        *VariableHeader = (VARIABLE_HEADER *)GET_GUID_HOB_DATA (GuidHob);
-      } else {
-        *VariableHeader   = (VARIABLE_HEADER *)BuildGuidHob (&gEfiCallerIdGuid, GetVariableHeaderSize (StoreInfo->AuthFlag));
-        PartialHeaderSize = (UINTN)TargetAddress - (UINTN)Variable;
-        //
-        // Partial content is in NV storage.
-        //
-        CopyMem ((UINT8 *)*VariableHeader, (UINT8 *)Variable, PartialHeaderSize);
-        //
-        // Another partial content is in spare block.
-        //
-        CopyMem ((UINT8 *)*VariableHeader + PartialHeaderSize, (UINT8 *)(UINTN)SpareAddress, GetVariableHeaderSize (StoreInfo->AuthFlag) - PartialHeaderSize);
-      }
-    }
-  } else {
-    if (Variable >= GetEndPointer (StoreInfo->VariableStoreHeader)) {
-      //
-      // Reach the end of variable store.
-      //
-      return FALSE;
-    }
-  }
-
-  return IsValidVariableHeader (*VariableHeader);
-}
-
-/**
-  Get variable name or data to output buffer.
-
-  @param  StoreInfo     Pointer to variable store info structure.
-  @param  NameOrData    Pointer to the variable name/data that may be inconsecutive.
-  @param  Size          Variable name/data size.
-  @param  Buffer        Pointer to output buffer to hold the variable name/data.
-
-**/
-VOID
-GetVariableNameOrData (
-  IN VARIABLE_STORE_INFO  *StoreInfo,
-  IN UINT8                *NameOrData,
-  IN UINTN                Size,
-  OUT UINT8               *Buffer
-  )
-{
-  EFI_PHYSICAL_ADDRESS  TargetAddress;
-  EFI_PHYSICAL_ADDRESS  SpareAddress;
-  UINTN                 PartialSize;
-
-  if (StoreInfo->FtwLastWriteData != NULL) {
-    TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
-    SpareAddress  = StoreInfo->FtwLastWriteData->SpareAddress;
-    if (((UINTN)NameOrData < (UINTN)TargetAddress) && (((UINTN)NameOrData + Size) > (UINTN)TargetAddress)) {
-      //
-      // Variable name/data is inconsecutive.
-      //
-      PartialSize = (UINTN)TargetAddress - (UINTN)NameOrData;
-      //
-      // Partial content is in NV storage.
-      //
-      CopyMem (Buffer, NameOrData, PartialSize);
-      //
-      // Another partial content is in spare block.
-      //
-      CopyMem (Buffer + PartialSize, (UINT8 *)(UINTN)SpareAddress, Size - PartialSize);
-      return;
-    }
-  }
-
-  //
-  // Variable name/data is consecutive.
-  //
-  CopyMem (Buffer, NameOrData, Size);
-}
-
 /**
   Find the variable in the specified variable store.
 
@@ -1246,3 +522,107 @@ PeiGetNextVariableName (
     }
   }
 }
+
+/**
+  This service retrieves a variable's value using its name and GUID.
+
+  Read the specified variable from the UEFI variable store. If the Data
+  buffer is too small to hold the contents of the variable, the error
+  EFI_BUFFER_TOO_SMALL is returned and DataSize is set to the required buffer
+  size to obtain the data.
+
+  @param  This                  A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
+  @param  VariableName          A pointer to a null-terminated string that is the variable's name.
+  @param  VariableGuid          A pointer to an EFI_GUID that is the variable's GUID. The combination of
+                                VariableGuid and VariableName must be unique.
+  @param  Attributes            If non-NULL, on return, points to the variable's attributes.
+  @param  DataSize              On entry, points to the size in bytes of the Data buffer.
+                                On return, points to the size of the data returned in Data.
+  @param  Data                  Points to the buffer which will hold the returned variable value.
+                                May be NULL with a zero DataSize in order to determine the size of the buffer needed.
+
+  @retval EFI_SUCCESS           The variable was read successfully.
+  @retval EFI_NOT_FOUND         The variable was be found.
+  @retval EFI_BUFFER_TOO_SMALL  The DataSize is too small for the resulting data.
+                                DataSize is updated with the size required for
+                                the specified variable.
+  @retval EFI_INVALID_PARAMETER VariableName, VariableGuid, DataSize or Data is NULL.
+  @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
+
+**/
+EFI_STATUS
+EFIAPI
+PeiGetVariableEx (
+  IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI  *This,
+  IN CONST  CHAR16                           *VariableName,
+  IN CONST  EFI_GUID                         *VariableGuid,
+  OUT       UINT32                           *Attributes,
+  IN OUT    UINTN                            *DataSize,
+  OUT       VOID                             *Data OPTIONAL
+  )
+{
+  EFI_STATUS  Status;
+
+  //
+  // If variable protection is employed, always get variable data through
+  // ProtectedVariableLib.
+  //
+  Status = ProtectedVariableLibGetByName (VariableName, VariableGuid, Attributes, DataSize, Data);
+  if (Status != EFI_UNSUPPORTED) {
+    return Status;
+  }
+
+  return PeiGetVariable (This, VariableName, VariableGuid, Attributes, DataSize, Data);
+}
+
+/**
+  Return the next variable name and GUID.
+
+  This function is called multiple times to retrieve the VariableName
+  and VariableGuid of all variables currently available in the system.
+  On each call, the previous results are passed into the interface,
+  and, on return, the interface returns the data for the next
+  interface. When the entire variable list has been returned,
+  EFI_NOT_FOUND is returned.
+
+  @param  This              A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
+
+  @param  VariableNameSize  On entry, points to the size of the buffer pointed to by VariableName.
+                            On return, the size of the variable name buffer.
+  @param  VariableName      On entry, a pointer to a null-terminated string that is the variable's name.
+                            On return, points to the next variable's null-terminated name string.
+  @param  VariableGuid      On entry, a pointer to an EFI_GUID that is the variable's GUID.
+                            On return, a pointer to the next variable's GUID.
+
+  @retval EFI_SUCCESS           The variable was read successfully.
+  @retval EFI_NOT_FOUND         The variable could not be found.
+  @retval EFI_BUFFER_TOO_SMALL  The VariableNameSize is too small for the resulting
+                                data. VariableNameSize is updated with the size
+                                required for the specified variable.
+  @retval EFI_INVALID_PARAMETER VariableName, VariableGuid or
+                                VariableNameSize is NULL.
+  @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
+
+**/
+EFI_STATUS
+EFIAPI
+PeiGetNextVariableNameEx (
+  IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI  *This,
+  IN OUT UINTN                               *VariableNameSize,
+  IN OUT CHAR16                              *VariableName,
+  IN OUT EFI_GUID                            *VariableGuid
+  )
+{
+  EFI_STATUS  Status;
+
+  //
+  // If variable protection is employed, always get next variable through
+  // ProtectedVariableLib.
+  //
+  Status = ProtectedVariableLibFindNext (VariableNameSize, VariableName, VariableGuid);
+  if (Status != EFI_UNSUPPORTED) {
+    return Status;
+  }
+
+  return PeiGetNextVariableName (This, VariableNameSize, VariableName, VariableGuid);
+}
diff --git a/MdeModulePkg/Universal/Variable/Pei/VariableParsing.c b/MdeModulePkg/Universal/Variable/Pei/VariableParsing.c
new file mode 100644
index 000000000000..2d605d39cbb6
--- /dev/null
+++ b/MdeModulePkg/Universal/Variable/Pei/VariableParsing.c
@@ -0,0 +1,941 @@
+/** @file
+  Implement ReadOnly Variable Services required by PEIM and install
+  PEI ReadOnly Varaiable2 PPI. These services operates the non volatile storage space.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include "Variable.h"
+#include "VariableStore.h"
+
+/**
+
+  Gets the pointer to the first variable header in given variable store area.
+
+  @param[in] VarStoreHeader  Pointer to the Variable Store Header.
+
+  @return Pointer to the first variable header.
+
+**/
+VARIABLE_HEADER *
+GetStartPointer (
+  IN VARIABLE_STORE_HEADER  *VarStoreHeader
+  )
+{
+  //
+  // The start of variable store
+  //
+  return (VARIABLE_HEADER *)HEADER_ALIGN (VarStoreHeader + 1);
+}
+
+/**
+
+  Gets the pointer to the end of the variable storage area.
+
+  This function gets pointer to the end of the variable storage
+  area, according to the input variable store header.
+
+  @param[in] VarStoreHeader  Pointer to the Variable Store Header.
+
+  @return Pointer to the end of the variable storage area.
+
+**/
+VARIABLE_HEADER *
+GetEndPointer (
+  IN VARIABLE_STORE_HEADER  *VarStoreHeader
+  )
+{
+  //
+  // The end of variable store
+  //
+  return (VARIABLE_HEADER *)HEADER_ALIGN ((UINTN)VarStoreHeader + VarStoreHeader->Size);
+}
+
+/**
+  This code checks if variable header is valid or not.
+
+  @param[in]  Variable  Pointer to the Variable Header.
+
+  @retval TRUE      Variable header is valid.
+  @retval FALSE     Variable header is not valid.
+
+**/
+BOOLEAN
+IsValidVariableHeader (
+  IN  VARIABLE_HEADER  *Variable
+  )
+{
+  if ((Variable == NULL) || (Variable->StartId != VARIABLE_DATA)) {
+    return FALSE;
+  }
+
+  return TRUE;
+}
+
+/**
+  This code gets the size of variable header.
+
+  @param[in] AuthFlag   Authenticated variable flag.
+
+  @return Size of variable header in bytes in type UINTN.
+
+**/
+UINTN
+GetVariableHeaderSize (
+  IN  BOOLEAN  AuthFlag
+  )
+{
+  UINTN  Value;
+
+  if (AuthFlag) {
+    Value = sizeof (AUTHENTICATED_VARIABLE_HEADER);
+  } else {
+    Value = sizeof (VARIABLE_HEADER);
+  }
+
+  return Value;
+}
+
+/**
+  This code gets the size of name of variable.
+
+  @param[in]  Variable  Pointer to the Variable Header.
+  @param[in]  AuthFlag  Authenticated variable flag.
+
+  @return Size of variable in bytes in type UINTN.
+
+**/
+UINTN
+NameSizeOfVariable (
+  IN  VARIABLE_HEADER  *Variable,
+  IN  BOOLEAN          AuthFlag
+  )
+{
+  AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
+
+  AuthVariable = (AUTHENTICATED_VARIABLE_HEADER *)Variable;
+  if (AuthFlag) {
+    if ((AuthVariable->State == (UINT8)(-1)) ||
+        (AuthVariable->DataSize == (UINT32)(-1)) ||
+        (AuthVariable->NameSize == (UINT32)(-1)) ||
+        (AuthVariable->Attributes == (UINT32)(-1)))
+    {
+      return 0;
+    }
+
+    return (UINTN)AuthVariable->NameSize;
+  } else {
+    if ((Variable->State == (UINT8)(-1)) ||
+        (Variable->DataSize == (UINT32)(-1)) ||
+        (Variable->NameSize == (UINT32)(-1)) ||
+        (Variable->Attributes == (UINT32)(-1)))
+    {
+      return 0;
+    }
+
+    return (UINTN)Variable->NameSize;
+  }
+}
+
+/**
+  This code gets the size of data of variable.
+
+  @param[in]  Variable  Pointer to the Variable Header.
+  @param[in]  AuthFlag  Authenticated variable flag.
+
+  @return Size of variable in bytes in type UINTN.
+
+**/
+UINTN
+DataSizeOfVariable (
+  IN  VARIABLE_HEADER  *Variable,
+  IN  BOOLEAN          AuthFlag
+  )
+{
+  AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
+
+  AuthVariable = (AUTHENTICATED_VARIABLE_HEADER *)Variable;
+  if (AuthFlag) {
+    if ((AuthVariable->State == (UINT8)(-1)) ||
+        (AuthVariable->DataSize == (UINT32)(-1)) ||
+        (AuthVariable->NameSize == (UINT32)(-1)) ||
+        (AuthVariable->Attributes == (UINT32)(-1)))
+    {
+      return 0;
+    }
+
+    return (UINTN)AuthVariable->DataSize;
+  } else {
+    if ((Variable->State == (UINT8)(-1)) ||
+        (Variable->DataSize == (UINT32)(-1)) ||
+        (Variable->NameSize == (UINT32)(-1)) ||
+        (Variable->Attributes == (UINT32)(-1)))
+    {
+      return 0;
+    }
+
+    return (UINTN)Variable->DataSize;
+  }
+}
+
+/**
+  This code gets the pointer to the variable name.
+
+  @param[in]   Variable  Pointer to the Variable Header.
+  @param[in]   AuthFlag  Authenticated variable flag.
+
+  @return  A CHAR16* pointer to Variable Name.
+
+**/
+CHAR16 *
+GetVariableNamePtr (
+  IN VARIABLE_HEADER  *Variable,
+  IN BOOLEAN          AuthFlag
+  )
+{
+  return (CHAR16 *)((UINTN)Variable + GetVariableHeaderSize (AuthFlag));
+}
+
+/**
+  This code gets the pointer to the variable guid.
+
+  @param[in] Variable   Pointer to the Variable Header.
+  @param[in] AuthFlag   Authenticated variable flag.
+
+  @return A EFI_GUID* pointer to Vendor Guid.
+
+**/
+EFI_GUID *
+GetVendorGuidPtr (
+  IN VARIABLE_HEADER  *Variable,
+  IN BOOLEAN          AuthFlag
+  )
+{
+  AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
+
+  AuthVariable = (AUTHENTICATED_VARIABLE_HEADER *)Variable;
+  if (AuthFlag) {
+    return &AuthVariable->VendorGuid;
+  } else {
+    return &Variable->VendorGuid;
+  }
+}
+
+/**
+  This code gets the pointer to the variable data.
+
+  @param[in]   Variable         Pointer to the Variable Header.
+  @param[in]   VariableHeader   Pointer to the Variable Header that has consecutive content.
+  @param[in]   AuthFlag         Authenticated variable flag.
+
+  @return  A UINT8* pointer to Variable Data.
+
+**/
+UINT8 *
+GetVariableDataPtr (
+  IN  VARIABLE_HEADER  *Variable,
+  IN  VARIABLE_HEADER  *VariableHeader,
+  IN  BOOLEAN          AuthFlag
+  )
+{
+  UINTN  Value;
+
+  //
+  // Be careful about pad size for alignment
+  //
+  Value  =  (UINTN)GetVariableNamePtr (Variable, AuthFlag);
+  Value += NameSizeOfVariable (VariableHeader, AuthFlag);
+  Value += GET_PAD_SIZE (NameSizeOfVariable (VariableHeader, AuthFlag));
+
+  return (UINT8 *)Value;
+}
+
+/**
+  This code gets the pointer to the next variable header.
+
+  @param[in]  StoreInfo         Pointer to variable store info structure.
+  @param[in]  Variable          Pointer to the Variable Header.
+  @param[in]  VariableHeader    Pointer to the Variable Header that has consecutive content.
+
+  @return  A VARIABLE_HEADER* pointer to next variable header.
+
+**/
+VARIABLE_HEADER *
+GetNextVariablePtr (
+  IN  VARIABLE_STORE_INFO  *StoreInfo,
+  IN  VARIABLE_HEADER      *Variable,
+  IN  VARIABLE_HEADER      *VariableHeader
+  )
+{
+  EFI_PHYSICAL_ADDRESS  TargetAddress;
+  EFI_PHYSICAL_ADDRESS  SpareAddress;
+  UINTN                 Value;
+
+  Value  =  (UINTN)GetVariableDataPtr (Variable, VariableHeader, StoreInfo->AuthFlag);
+  Value += DataSizeOfVariable (VariableHeader, StoreInfo->AuthFlag);
+  Value += GET_PAD_SIZE (DataSizeOfVariable (VariableHeader, StoreInfo->AuthFlag));
+  //
+  // Be careful about pad size for alignment
+  //
+  Value = HEADER_ALIGN (Value);
+
+  if (StoreInfo->FtwLastWriteData != NULL) {
+    TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
+    SpareAddress  = StoreInfo->FtwLastWriteData->SpareAddress;
+    if (((UINTN)Variable < (UINTN)TargetAddress) && (Value >= (UINTN)TargetAddress)) {
+      //
+      // Next variable is in spare block.
+      //
+      Value = (UINTN)SpareAddress + (Value - (UINTN)TargetAddress);
+    }
+  }
+
+  return (VARIABLE_HEADER *)Value;
+}
+
+/**
+  Compare two variable names, one of them may be inconsecutive.
+
+  @param[in] StoreInfo      Pointer to variable store info structure.
+  @param[in] Name1          Pointer to one variable name.
+  @param[in] Name2          Pointer to another variable name.
+  @param[in] NameSize       Variable name size.
+
+  @retval TRUE          Name1 and Name2 are identical.
+  @retval FALSE         Name1 and Name2 are not identical.
+
+**/
+BOOLEAN
+CompareVariableName (
+  IN VARIABLE_STORE_INFO  *StoreInfo,
+  IN CONST CHAR16         *Name1,
+  IN CONST CHAR16         *Name2,
+  IN UINTN                NameSize
+  )
+{
+  EFI_PHYSICAL_ADDRESS  TargetAddress;
+  EFI_PHYSICAL_ADDRESS  SpareAddress;
+  UINTN                 PartialNameSize;
+
+  if (StoreInfo->FtwLastWriteData != NULL) {
+    TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
+    SpareAddress  = StoreInfo->FtwLastWriteData->SpareAddress;
+    if (((UINTN)Name1 < (UINTN)TargetAddress) && (((UINTN)Name1 + NameSize) > (UINTN)TargetAddress)) {
+      //
+      // Name1 is inconsecutive.
+      //
+      PartialNameSize = (UINTN)TargetAddress - (UINTN)Name1;
+      //
+      // Partial content is in NV storage.
+      //
+      if (CompareMem ((UINT8 *)Name1, (UINT8 *)Name2, PartialNameSize) == 0) {
+        //
+        // Another partial content is in spare block.
+        //
+        if (CompareMem ((UINT8 *)(UINTN)SpareAddress, (UINT8 *)Name2 + PartialNameSize, NameSize - PartialNameSize) == 0) {
+          return TRUE;
+        }
+      }
+
+      return FALSE;
+    } else if (((UINTN)Name2 < (UINTN)TargetAddress) && (((UINTN)Name2 + NameSize) > (UINTN)TargetAddress)) {
+      //
+      // Name2 is inconsecutive.
+      //
+      PartialNameSize = (UINTN)TargetAddress - (UINTN)Name2;
+      //
+      // Partial content is in NV storage.
+      //
+      if (CompareMem ((UINT8 *)Name2, (UINT8 *)Name1, PartialNameSize) == 0) {
+        //
+        // Another partial content is in spare block.
+        //
+        if (CompareMem ((UINT8 *)(UINTN)SpareAddress, (UINT8 *)Name1 + PartialNameSize, NameSize - PartialNameSize) == 0) {
+          return TRUE;
+        }
+      }
+
+      return FALSE;
+    }
+  }
+
+  //
+  // Both Name1 and Name2 are consecutive.
+  //
+  if (CompareMem ((UINT8 *)Name1, (UINT8 *)Name2, NameSize) == 0) {
+    return TRUE;
+  }
+
+  return FALSE;
+}
+
+/**
+  This function compares a variable with variable entries in database.
+
+  @param[in]   StoreInfo        Pointer to variable store info structure.
+  @param[in]   Variable         Pointer to the variable in our database
+  @param[in]   VariableHeader   Pointer to the Variable Header that has
+                                consecutive content.
+  @param[in]   VariableName     Name of the variable to compare to 'Variable'
+  @param[in]   VendorGuid       GUID of the variable to compare to 'Variable'
+  @param[out]  PtrTrack         Variable Track Pointer structure that contains
+                                Variable Information.
+
+  @retval EFI_SUCCESS    Found match variable
+  @retval EFI_NOT_FOUND  Variable not found
+
+**/
+EFI_STATUS
+CompareWithValidVariable (
+  IN  VARIABLE_STORE_INFO     *StoreInfo,
+  IN  VARIABLE_HEADER         *Variable,
+  IN  VARIABLE_HEADER         *VariableHeader,
+  IN  CONST CHAR16            *VariableName,
+  IN  CONST EFI_GUID          *VendorGuid,
+  OUT VARIABLE_POINTER_TRACK  *PtrTrack
+  )
+{
+  VOID      *Point;
+  EFI_GUID  *TempVendorGuid;
+
+  TempVendorGuid = GetVendorGuidPtr (VariableHeader, StoreInfo->AuthFlag);
+
+  if (VariableName[0] == 0) {
+    PtrTrack->CurrPtr = Variable;
+    return EFI_SUCCESS;
+  } else {
+    //
+    // Don't use CompareGuid function here for performance reasons.
+    // Instead we compare the GUID a UINT32 at a time and branch
+    // on the first failed comparison.
+    //
+    if ((((INT32 *)VendorGuid)[0] == ((INT32 *)TempVendorGuid)[0]) &&
+        (((INT32 *)VendorGuid)[1] == ((INT32 *)TempVendorGuid)[1]) &&
+        (((INT32 *)VendorGuid)[2] == ((INT32 *)TempVendorGuid)[2]) &&
+        (((INT32 *)VendorGuid)[3] == ((INT32 *)TempVendorGuid)[3])
+        )
+    {
+      ASSERT (NameSizeOfVariable (VariableHeader, StoreInfo->AuthFlag) != 0);
+      Point = (VOID *)GetVariableNamePtr (Variable, StoreInfo->AuthFlag);
+      if (CompareVariableName (StoreInfo, VariableName, Point, NameSizeOfVariable (VariableHeader, StoreInfo->AuthFlag))) {
+        PtrTrack->CurrPtr = Variable;
+        return EFI_SUCCESS;
+      }
+    }
+  }
+
+  return EFI_NOT_FOUND;
+}
+
+/**
+  Get variable header that has consecutive content.
+
+  @param[in]  StoreInfo       Pointer to variable store info structure.
+  @param[in]  Variable        Pointer to the Variable Header.
+  @param[out] VariableHeader  Pointer to Pointer to the Variable Header
+                              that has consecutive content.
+
+  @retval TRUE          Variable header is valid.
+  @retval FALSE         Variable header is not valid.
+
+**/
+BOOLEAN
+GetVariableHeader (
+  IN VARIABLE_STORE_INFO  *StoreInfo,
+  IN VARIABLE_HEADER      *Variable,
+  OUT VARIABLE_HEADER     **VariableHeader
+  )
+{
+  EFI_PHYSICAL_ADDRESS  TargetAddress;
+  EFI_PHYSICAL_ADDRESS  SpareAddress;
+  EFI_HOB_GUID_TYPE     *GuidHob;
+  UINTN                 PartialHeaderSize;
+
+  if (Variable == NULL) {
+    return FALSE;
+  }
+
+  //
+  // First assume variable header pointed by Variable is consecutive.
+  //
+  *VariableHeader = Variable;
+
+  if (StoreInfo->FtwLastWriteData != NULL) {
+    TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
+    SpareAddress  = StoreInfo->FtwLastWriteData->SpareAddress;
+    if (((UINTN)Variable > (UINTN)SpareAddress) &&
+        (((UINTN)Variable - (UINTN)SpareAddress + (UINTN)TargetAddress) >= (UINTN)GetEndPointer (StoreInfo->VariableStoreHeader)))
+    {
+      //
+      // Reach the end of variable store.
+      //
+      return FALSE;
+    }
+
+    if (((UINTN)Variable < (UINTN)TargetAddress) && (((UINTN)Variable + GetVariableHeaderSize (StoreInfo->AuthFlag)) > (UINTN)TargetAddress)) {
+      //
+      // Variable header pointed by Variable is inconsecutive,
+      // create a guid hob to combine the two partial variable header content together.
+      //
+      GuidHob = GetFirstGuidHob (&gEfiCallerIdGuid);
+      if (GuidHob != NULL) {
+        *VariableHeader = (VARIABLE_HEADER *)GET_GUID_HOB_DATA (GuidHob);
+      } else {
+        *VariableHeader   = (VARIABLE_HEADER *)BuildGuidHob (&gEfiCallerIdGuid, GetVariableHeaderSize (StoreInfo->AuthFlag));
+        PartialHeaderSize = (UINTN)TargetAddress - (UINTN)Variable;
+        //
+        // Partial content is in NV storage.
+        //
+        CopyMem ((UINT8 *)*VariableHeader, (UINT8 *)Variable, PartialHeaderSize);
+        //
+        // Another partial content is in spare block.
+        //
+        CopyMem ((UINT8 *)*VariableHeader + PartialHeaderSize, (UINT8 *)(UINTN)SpareAddress, GetVariableHeaderSize (StoreInfo->AuthFlag) - PartialHeaderSize);
+      }
+    }
+  } else {
+    if (Variable >= GetEndPointer (StoreInfo->VariableStoreHeader)) {
+      //
+      // Reach the end of variable store.
+      //
+      return FALSE;
+    }
+  }
+
+  return IsValidVariableHeader (*VariableHeader);
+}
+
+/**
+  Get variable name or data to output buffer.
+
+  @param[in]   StoreInfo     Pointer to variable store info structure.
+  @param[in]   NameOrData    Pointer to the variable name/data that may be inconsecutive.
+  @param[in]   Size          Variable name/data size.
+  @param[out]  Buffer        Pointer to output buffer to hold the variable name/data.
+
+**/
+VOID
+GetVariableNameOrData (
+  IN VARIABLE_STORE_INFO  *StoreInfo,
+  IN UINT8                *NameOrData,
+  IN UINTN                Size,
+  OUT UINT8               *Buffer
+  )
+{
+  EFI_PHYSICAL_ADDRESS  TargetAddress;
+  EFI_PHYSICAL_ADDRESS  SpareAddress;
+  UINTN                 PartialSize;
+
+  if (StoreInfo->FtwLastWriteData != NULL) {
+    TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
+    SpareAddress  = StoreInfo->FtwLastWriteData->SpareAddress;
+    if (((UINTN)NameOrData < (UINTN)TargetAddress) && (((UINTN)NameOrData + Size) > (UINTN)TargetAddress)) {
+      //
+      // Variable name/data is inconsecutive.
+      //
+      PartialSize = (UINTN)TargetAddress - (UINTN)NameOrData;
+      //
+      // Partial content is in NV storage.
+      //
+      CopyMem (Buffer, NameOrData, PartialSize);
+      //
+      // Another partial content is in spare block.
+      //
+      CopyMem (Buffer + PartialSize, (UINT8 *)(UINTN)SpareAddress, Size - PartialSize);
+      return;
+    }
+  }
+
+  //
+  // Variable name/data is consecutive.
+  //
+  CopyMem (Buffer, NameOrData, Size);
+}
+
+/**
+
+  Internal function to retrieve variable information.
+
+  @param[in,out] VariableInfo     Pointer to variable information.
+  @param[in]     StoreInfo        Pointer to store copy of variable (optional).
+  @param[in]     VariablePtr      Pointer to variable buffer.
+  @param[in]     VariableHeader   Pointer to variable header.
+
+  @retval EFI_INVALID_PARAMETER  One ore more required parameters are NULL.
+  @retval EFI_BUFFER_TOO_SMALL   Given buffer is too small to hold data.
+  @retval EFI_SUCCESS            Variable details are retrieved successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+GetVariableInfoInternal (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VariableInfo,
+  IN      VARIABLE_STORE_INFO      *StoreInfo OPTIONAL,
+  IN      VARIABLE_HEADER          *VariablePtr,
+  IN      VARIABLE_HEADER          *VariableHeader
+  )
+{
+  VARIABLE_HEADER                *VariableBuffer;
+  AUTHENTICATED_VARIABLE_HEADER  *AuthVariableHeader;
+  UINTN                          NameSize;
+  UINTN                          DataSize;
+  UINTN                          VariableSize;
+
+  if ((VariableInfo == NULL) || (VariablePtr == NULL) || (VariableHeader == NULL)) {
+    ASSERT (VariableInfo != NULL);
+    ASSERT (VariablePtr != NULL);
+    ASSERT (VariableHeader != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  VariableBuffer = VariableInfo->Buffer;
+
+  //
+  // Make a copy of the whole variable if VariableInfo->Buffer is given. But
+  // don't do this if StoreInfo is not given, because VariableInfo->Buffer
+  // has already hold a copy of variable in such situation.
+  //
+  NameSize = NameSizeOfVariable (VariableHeader, VariableInfo->Flags.Auth);
+  DataSize = DataSizeOfVariable (VariableHeader, VariableInfo->Flags.Auth);
+  if ((VariableBuffer != NULL) && (VariableBuffer != VariablePtr)) {
+    if (StoreInfo != NULL) {
+      CopyMem (
+        VariableBuffer,
+        VariableHeader,
+        GetVariableHeaderSize (VariableInfo->Flags.Auth)
+        );
+      GetVariableNameOrData (
+        StoreInfo,
+        (UINT8 *)GetVariableNamePtr (VariablePtr, VariableInfo->Flags.Auth),
+        NameSize,
+        (UINT8 *)GetVariableNamePtr (VariableBuffer, VariableInfo->Flags.Auth)
+        );
+      GetVariableNameOrData (
+        StoreInfo,
+        (UINT8 *)GetVariableDataPtr (VariablePtr, VariableHeader, VariableInfo->Flags.Auth),
+        DataSize,
+        (UINT8 *)GetVariableDataPtr (VariableBuffer, VariableHeader, VariableInfo->Flags.Auth)
+        );
+    } else {
+      //
+      // Suppose the variable is in consecutive space.
+      //
+      VariableSize = GetVariableHeaderSize (VariableInfo->Flags.Auth)
+                     + NameSize + GET_PAD_SIZE (NameSize)
+                     + DataSize;
+      CopyMem (VariableBuffer, VariablePtr, VariableSize);
+    }
+  }
+
+  //
+  // Generally, if no consecutive buffer passed in, don't return back any data.
+  //
+  // If follow pointers are NULL, return back pointers to following data inside
+  // VariableInfo->Buffer, if it's given.
+  //
+  //  VariableInfo->Header.VariableName
+  //  VariableInfo->Header.Data
+  //  VariableInfo->Header.VendorGuid
+  //  VariableInfo->Header.TimeStamp
+  //
+  // Otherwise, suppose they're buffers used to hold a copy of corresponding
+  // data.
+  //
+  //
+
+  //
+  // AuthVariable header
+  //
+  if (VariableInfo->Flags.Auth) {
+    AuthVariableHeader = (AUTHENTICATED_VARIABLE_HEADER *)VariableHeader;
+
+    VariableInfo->Header.State          = AuthVariableHeader->State;
+    VariableInfo->Header.Attributes     = AuthVariableHeader->Attributes;
+    VariableInfo->Header.PubKeyIndex    = AuthVariableHeader->PubKeyIndex;
+    VariableInfo->Header.MonotonicCount = ReadUnaligned64 (
+                                            &(AuthVariableHeader->MonotonicCount)
+                                            );
+    if (VariableInfo->Header.TimeStamp != NULL) {
+      CopyMem (
+        VariableInfo->Header.TimeStamp,
+        &AuthVariableHeader->TimeStamp,
+        sizeof (EFI_TIME)
+        );
+    } else if (VariableBuffer != NULL) {
+      AuthVariableHeader             = (AUTHENTICATED_VARIABLE_HEADER *)VariableBuffer;
+      VariableInfo->Header.TimeStamp = &AuthVariableHeader->TimeStamp;
+    }
+  } else {
+    VariableInfo->Header.State          = VariableHeader->State;
+    VariableInfo->Header.Attributes     = VariableHeader->Attributes;
+    VariableInfo->Header.PubKeyIndex    = 0;
+    VariableInfo->Header.MonotonicCount = 0;
+    VariableInfo->Header.TimeStamp      = NULL;
+  }
+
+  //
+  // VendorGuid
+  //
+  if (VariableInfo->Header.VendorGuid != NULL) {
+    CopyGuid (
+      VariableInfo->Header.VendorGuid,
+      GetVendorGuidPtr (VariableHeader, VariableInfo->Flags.Auth)
+      );
+  } else if (VariableBuffer != NULL) {
+    VariableInfo->Header.VendorGuid
+      = GetVendorGuidPtr (VariableBuffer, VariableInfo->Flags.Auth);
+  }
+
+  //
+  // VariableName
+  //
+  if (  (VariableInfo->Header.VariableName != NULL)
+     && (VariableInfo->Header.NameSize >= NameSize))
+  {
+    GetVariableNameOrData (
+      StoreInfo,
+      (UINT8 *)GetVariableNamePtr (VariablePtr, VariableInfo->Flags.Auth),
+      NameSize,
+      (UINT8 *)VariableInfo->Header.VariableName
+      );
+  } else if (VariableBuffer != NULL) {
+    VariableInfo->Header.VariableName
+      = GetVariableNamePtr (VariableBuffer, VariableInfo->Flags.Auth);
+  } else if (VariableInfo->Header.VariableName != NULL) {
+    return EFI_BUFFER_TOO_SMALL;
+  }
+
+  //
+  // Data
+  //
+  if (  (VariableInfo->Header.Data != NULL)
+     && (VariableInfo->Header.DataSize >= DataSize))
+  {
+    GetVariableNameOrData (
+      StoreInfo,
+      GetVariableDataPtr (VariablePtr, VariableHeader, StoreInfo->AuthFlag),
+      DataSize,
+      VariableInfo->Header.Data
+      );
+  } else if (VariableBuffer != NULL) {
+    VariableInfo->Header.Data
+      = GetVariableDataPtr (VariableBuffer, VariableBuffer, VariableInfo->Flags.Auth);
+  } else if (VariableInfo->Header.Data != NULL) {
+    return EFI_BUFFER_TOO_SMALL;
+  }
+
+  //
+  // Update size information about name & data.
+  //
+  VariableInfo->Header.NameSize = NameSize;
+  VariableInfo->Header.DataSize = DataSize;
+
+  return EFI_SUCCESS;
+}
+
+/**
+
+  Retrieve details about a variable, given by VariableInfo->Buffer or
+  VariableInfo->Index, and pass the details back in VariableInfo->Header.
+
+  This function is used to resolve the variable data structure into
+  VariableInfo->Header, for easier access later without revisiting the variable
+  data in variable store. If pointers in the structure of VariableInfo->Header
+  are not NULL, it's supposed that they are buffers passed in to hold a copy of
+  data of corresponding data fields in variable data structure. Otherwise, this
+  function simply returns pointers pointing to address of those data fields.
+
+  The variable is specified by either VariableInfo->Index or VariableInfo->Buffer.
+  If VariableInfo->Index is given, this function finds the corresponding variable
+  first from variable storage according to the Index.
+
+  If both VariableInfo->Index and VariableInfo->Buffer are given, it's supposed
+  that VariableInfo->Buffer is a buffer passed in to hold a whole copy of
+  requested variable data to be returned.
+
+  @param[in,out] VariableInfo             Pointer to variable information.
+
+  @retval EFI_INVALID_PARAMETER  VariableInfo is NULL or both VariableInfo->Buffer
+                                 and VariableInfo->Index are NULL (0).
+  @retval EFI_NOT_FOUND          If given Buffer or Index is out of range of
+                                 any given or internal storage copies.
+  @retval EFI_SUCCESS            Variable details are retrieved successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+GetVariableInfo (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VariableInfo
+  )
+{
+  VARIABLE_HEADER      *VariablePtr;
+  VARIABLE_HEADER      *VariableHeader;
+  VARIABLE_STORE_TYPE  StoreType;
+  VARIABLE_STORE_INFO  StoreInfo;
+  UINTN                Offset;
+
+  if ((VariableInfo == NULL) ||
+      ((VariableInfo->Buffer == NULL) && (VariableInfo->StoreIndex == VAR_INDEX_INVALID)))
+  {
+    ASSERT (VariableInfo != NULL);
+    ASSERT (VariableInfo->StoreIndex != VAR_INDEX_INVALID || VariableInfo->Buffer != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  StoreInfo.VariableStoreHeader = NULL;
+  for (StoreType = VariableStoreTypeHob; StoreType < VariableStoreTypeMax; ++StoreType) {
+    GetVariableStore (StoreType, &StoreInfo);
+    if (StoreInfo.VariableStoreHeader != NULL) {
+      break;
+    }
+  }
+
+  ASSERT (StoreInfo.VariableStoreHeader != NULL);
+
+  //
+  // No StoreIndex? Don't retrieve variable information from store but just from
+  // VariableInfo->Buffer.
+  //
+  if (VariableInfo->StoreIndex == VAR_INDEX_INVALID) {
+    VariablePtr    = VariableInfo->Buffer;
+    VariableHeader = VariablePtr;
+
+    return GetVariableInfoInternal (VariableInfo, NULL, VariablePtr, VariableHeader);
+  }
+
+  Offset = (UINTN)VariableInfo->StoreIndex;
+  if (  (StoreInfo.FtwLastWriteData != NULL)
+     && (Offset >= ((UINTN)StoreInfo.FtwLastWriteData->TargetAddress
+                    - (UINTN)StoreInfo.VariableStoreHeader)))
+  {
+    Offset -= ((UINTN)StoreInfo.FtwLastWriteData->TargetAddress
+               - (UINTN)StoreInfo.VariableStoreHeader);
+    VariablePtr = (VARIABLE_HEADER *)
+                  ((UINTN)StoreInfo.FtwLastWriteData->SpareAddress + Offset);
+  } else {
+    VariablePtr = (VARIABLE_HEADER *)
+                  ((UINTN)StoreInfo.VariableStoreHeader + Offset);
+  }
+
+  //
+  // Note that variable might be in unconsecutive space. Always get a copy
+  // of its header in consecutive buffer.
+  //
+  if (!GetVariableHeader (&StoreInfo, VariablePtr, &VariableHeader)) {
+    return EFI_NOT_FOUND;
+  }
+
+  return GetVariableInfoInternal (VariableInfo, &StoreInfo, VariablePtr, VariableHeader);
+}
+
+/**
+
+  Retrieve details of the variable next to given variable within VariableStore.
+
+  If VarInfo->Buffer is NULL, the first one in VariableStore is returned.
+
+  VariableStart and/or VariableEnd can be given optionally for the situation
+  in which the valid storage space is smaller than the VariableStore->Size.
+  This usually happens when PEI variable services make a compact variable
+  cache to save memory, which cannot make use VariableStore->Size to determine
+  the correct variable storage range.
+
+  @param[in,out] VariableInfo             Pointer to variable information.
+
+  @retval EFI_INVALID_PARAMETER  VariableInfo or VariableStore is NULL.
+  @retval EFI_NOT_FOUND          If the end of VariableStore is reached.
+  @retval EFI_SUCCESS            The next variable is retrieved successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+GetNextVariableInfo (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VariableInfo
+  )
+{
+  VARIABLE_HEADER      *VariablePtr;
+  VARIABLE_HEADER      *VariableHeader;
+  VARIABLE_STORE_INFO  StoreInfo;
+  VARIABLE_STORE_TYPE  StoreType;
+  UINTN                Offset;
+
+  if (VariableInfo == NULL) {
+    ASSERT (VariableInfo != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  StoreInfo.VariableStoreHeader = NULL;
+  for (StoreType = VariableStoreTypeHob; StoreType < VariableStoreTypeMax; ++StoreType) {
+    GetVariableStore (StoreType, &StoreInfo);
+    if (StoreInfo.VariableStoreHeader != NULL) {
+      break;
+    }
+  }
+
+  ASSERT (StoreInfo.VariableStoreHeader != NULL);
+
+  //
+  // VariableInfo->StoreIndex is supposed to be the index to variable found
+  // last time. Use it to get the variable next to it in store. If it's invalid,
+  // return the first variable available in store.
+  //
+  VariableInfo->Flags.Auth = StoreInfo.AuthFlag;
+  if (VariableInfo->StoreIndex == VAR_INDEX_INVALID) {
+    VariablePtr = GetStartPointer (StoreInfo.VariableStoreHeader);
+  } else {
+    Offset = (UINTN)VariableInfo->StoreIndex;
+    if (  (StoreInfo.FtwLastWriteData != NULL)
+       && (Offset >= ((UINTN)StoreInfo.FtwLastWriteData->TargetAddress
+                      - (UINTN)StoreInfo.VariableStoreHeader)))
+    {
+      Offset -= ((UINTN)StoreInfo.FtwLastWriteData->TargetAddress
+                 - (UINTN)StoreInfo.VariableStoreHeader);
+      VariablePtr = (VARIABLE_HEADER *)
+                    ((UINTN)StoreInfo.FtwLastWriteData->SpareAddress + Offset);
+    } else {
+      VariablePtr = (VARIABLE_HEADER *)
+                    ((UINTN)StoreInfo.VariableStoreHeader + Offset);
+    }
+
+    //
+    // Note that variable might be in unconsecutive space. Always get a copy
+    // of its header in consecutive buffer.
+    //
+    if (!GetVariableHeader (&StoreInfo, VariablePtr, &VariableHeader)) {
+      return EFI_NOT_FOUND;
+    }
+
+    VariablePtr = GetNextVariablePtr (&StoreInfo, VariablePtr, VariableHeader);
+  }
+
+  //
+  // Get a copy of variable header in consecutive buffer.
+  //
+  if (!GetVariableHeader (&StoreInfo, VariablePtr, &VariableHeader)) {
+    return EFI_NOT_FOUND;
+  }
+
+  //
+  // Use the offset to the start of variable store as index of the variable.
+  //
+  if (  (StoreInfo.FtwLastWriteData == NULL)
+     || ((UINTN)VariablePtr < (UINTN)StoreInfo.FtwLastWriteData->TargetAddress))
+  {
+    VariableInfo->StoreIndex
+      = (UINT64)((UINTN)VariablePtr - (UINTN)StoreInfo.VariableStoreHeader);
+  } else {
+    VariableInfo->StoreIndex
+      = (UINT64)((UINTN)StoreInfo.FtwLastWriteData->TargetAddress
+                 - (UINTN)StoreInfo.VariableStoreHeader);
+    VariableInfo->StoreIndex
+      += (UINT64)((UINTN)VariablePtr - (UINTN)StoreInfo.FtwLastWriteData->SpareAddress);
+  }
+
+  if ((StoreType == VariableStoreTypeHob) && (VariableInfo->Buffer == NULL)) {
+    VariableInfo->Buffer = VariablePtr;
+  }
+
+  return GetVariableInfoInternal (VariableInfo, &StoreInfo, VariablePtr, VariableHeader);
+}
diff --git a/MdeModulePkg/Universal/Variable/Pei/VariableStore.c b/MdeModulePkg/Universal/Variable/Pei/VariableStore.c
new file mode 100644
index 000000000000..72bd17a43048
--- /dev/null
+++ b/MdeModulePkg/Universal/Variable/Pei/VariableStore.c
@@ -0,0 +1,305 @@
+/** @file
+  Implement ReadOnly Variable Services required by PEIM and install
+  PEI ReadOnly Varaiable2 PPI. These services operates the non volatile storage space.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include "VariableParsing.h"
+#include "VariableStore.h"
+
+/**
+  Get variable store status.
+
+  @param[in]  VarStoreHeader  Pointer to the Variable Store Header.
+
+  @retval  EfiRaw      Variable store is raw
+  @retval  EfiValid    Variable store is valid
+  @retval  EfiInvalid  Variable store is invalid
+
+**/
+VARIABLE_STORE_STATUS
+GetVariableStoreStatus (
+  IN VARIABLE_STORE_HEADER  *VarStoreHeader
+  )
+{
+  if ((CompareGuid (&VarStoreHeader->Signature, &gEfiAuthenticatedVariableGuid) ||
+       CompareGuid (&VarStoreHeader->Signature, &gEfiVariableGuid)) &&
+      (VarStoreHeader->Format == VARIABLE_STORE_FORMATTED) &&
+      (VarStoreHeader->State == VARIABLE_STORE_HEALTHY)
+      )
+  {
+    return EfiValid;
+  }
+
+  if ((((UINT32 *)(&VarStoreHeader->Signature))[0] == 0xffffffff) &&
+      (((UINT32 *)(&VarStoreHeader->Signature))[1] == 0xffffffff) &&
+      (((UINT32 *)(&VarStoreHeader->Signature))[2] == 0xffffffff) &&
+      (((UINT32 *)(&VarStoreHeader->Signature))[3] == 0xffffffff) &&
+      (VarStoreHeader->Size == 0xffffffff) &&
+      (VarStoreHeader->Format == 0xff) &&
+      (VarStoreHeader->State == 0xff)
+      )
+  {
+    return EfiRaw;
+  } else {
+    return EfiInvalid;
+  }
+}
+
+/**
+  Reports HOB variable store is available or not.
+
+  @retval EFI_NOT_READY  HOB variable store info not available.
+  @retval EFI_NOT_FOUND  HOB variable store is NOT available.
+  @retval EFI_SUCCESS    HOB variable store is available.
+**/
+EFI_STATUS
+EFIAPI
+IsHobVariableStoreAvailable (
+  VOID
+  )
+{
+  EFI_HOB_GUID_TYPE  *GuidHob;
+  VOID               *VariableStoreInfoHob;
+
+  //
+  // Discover if Variable Store Info Hob has been published by platform driver.
+  // It contains information regards to HOB or NV Variable Store availability
+  //
+  GuidHob = GetFirstGuidHob (&gEfiPeiVariableStoreDiscoveredPpiGuid);
+  if (GuidHob == NULL) {
+    return EFI_NOT_READY;
+  }
+
+  //
+  // Check if HOB Variable Store is available
+  //
+  VariableStoreInfoHob = GET_GUID_HOB_DATA (GuidHob);
+  if (*(BOOLEAN *)VariableStoreInfoHob == TRUE) {
+    return EFI_SUCCESS;
+  }
+
+  //
+  // This might be NV Variable Store
+  //
+  return EFI_NOT_FOUND;
+}
+
+/**
+  Get HOB variable store.
+
+  @param[out] StoreInfo             Return the store info.
+
+**/
+VOID
+GetHobVariableStore (
+  OUT VARIABLE_STORE_INFO  *StoreInfo
+  )
+{
+  EFI_HOB_GUID_TYPE  *GuidHob;
+
+  //
+  // Make sure there is no more than one Variable HOB.
+  //
+  DEBUG_CODE_BEGIN ();
+  GuidHob = GetFirstGuidHob (&gEfiAuthenticatedVariableGuid);
+  if (GuidHob != NULL) {
+    if ((GetNextGuidHob (&gEfiAuthenticatedVariableGuid, GET_NEXT_HOB (GuidHob)) != NULL)) {
+      DEBUG ((DEBUG_ERROR, "ERROR: Found two Auth Variable HOBs\n"));
+      ASSERT (FALSE);
+    } else if (GetFirstGuidHob (&gEfiVariableGuid) != NULL) {
+      DEBUG ((DEBUG_ERROR, "ERROR: Found one Auth + one Normal Variable HOBs\n"));
+      ASSERT (FALSE);
+    }
+  } else {
+    GuidHob = GetFirstGuidHob (&gEfiVariableGuid);
+    if (GuidHob != NULL) {
+      if ((GetNextGuidHob (&gEfiVariableGuid, GET_NEXT_HOB (GuidHob)) != NULL)) {
+        DEBUG ((DEBUG_ERROR, "ERROR: Found two Normal Variable HOBs\n"));
+        ASSERT (FALSE);
+      }
+    }
+  }
+
+  DEBUG_CODE_END ();
+
+  GuidHob = GetFirstGuidHob (&gEfiAuthenticatedVariableGuid);
+  if (GuidHob != NULL) {
+    StoreInfo->VariableStoreHeader = (VARIABLE_STORE_HEADER *)GET_GUID_HOB_DATA (GuidHob);
+    StoreInfo->AuthFlag            = TRUE;
+  } else {
+    GuidHob = GetFirstGuidHob (&gEfiVariableGuid);
+    if (GuidHob != NULL) {
+      StoreInfo->VariableStoreHeader = (VARIABLE_STORE_HEADER *)GET_GUID_HOB_DATA (GuidHob);
+      StoreInfo->AuthFlag            = FALSE;
+    }
+  }
+}
+
+/**
+  Get NV variable store.
+
+  @param[out] StoreInfo             Return the store info.
+  @param[out] VariableFvHeader      Return header of FV containing the store.
+
+**/
+VOID
+GetNvVariableStore (
+  OUT VARIABLE_STORE_INFO         *StoreInfo,
+  OUT EFI_FIRMWARE_VOLUME_HEADER  **VariableFvHeader
+  )
+{
+  EFI_HOB_GUID_TYPE                     *GuidHob;
+  EFI_FIRMWARE_VOLUME_HEADER            *FvHeader;
+  VARIABLE_STORE_HEADER                 *StoreHeader;
+  FAULT_TOLERANT_WRITE_LAST_WRITE_DATA  *HobData;
+  FAULT_TOLERANT_WRITE_LAST_WRITE_DATA  *FtwLastWriteData;
+  EFI_PHYSICAL_ADDRESS                  NvStorageBase;
+  UINT32                                NvStorageSize;
+  UINT32                                BackUpOffset;
+
+  NvStorageSize = PcdGet32 (PcdFlashNvStorageVariableSize);
+  NvStorageBase = (EFI_PHYSICAL_ADDRESS)
+                  (PcdGet64 (PcdFlashNvStorageVariableBase64) != 0)
+                  ? PcdGet64 (PcdFlashNvStorageVariableBase64)
+                  : PcdGet32 (PcdFlashNvStorageVariableBase);
+  ASSERT (NvStorageBase != 0);
+
+  FvHeader = (EFI_FIRMWARE_VOLUME_HEADER *)(UINTN)NvStorageBase;
+
+  //
+  // Check the FTW last write data hob.
+  //
+  BackUpOffset     = 0;
+  FtwLastWriteData = NULL;
+  HobData          = NULL;
+  GuidHob          = GetFirstGuidHob (&gEdkiiFaultTolerantWriteGuid);
+
+  if (GuidHob != NULL) {
+    HobData = (FAULT_TOLERANT_WRITE_LAST_WRITE_DATA *)GET_GUID_HOB_DATA (GuidHob);
+    if (HobData->TargetAddress == NvStorageBase) {
+      //
+      // Let FvHeader point to spare block.
+      //
+      DEBUG ((
+        EFI_D_INFO,
+        "PeiVariable: NV storage is backed up in spare block: 0x%x\n",
+        (UINTN)HobData->SpareAddress
+        ));
+
+      FvHeader = (EFI_FIRMWARE_VOLUME_HEADER *)(UINTN)HobData->SpareAddress;
+      HobData  = NULL;
+    } else if ((HobData->TargetAddress > NvStorageBase) &&
+               (HobData->TargetAddress < (NvStorageBase + NvStorageSize)))
+    {
+      //
+      // Flash NV storage from the offset is backed up in spare block.
+      //
+      BackUpOffset = (UINT32)(HobData->TargetAddress - NvStorageBase);
+      DEBUG ((
+        EFI_D_INFO,
+        "PeiVariable: High partial NV storage from offset: %x is backed up in spare block: 0x%x\n",
+        BackUpOffset,
+        (UINTN)FtwLastWriteData->SpareAddress
+        ));
+      //
+      // At least one block data in flash NV storage is still valid, so still
+      // leave FvHeader point to NV storage base.
+      //
+    }
+  }
+
+  if (StoreInfo != NULL) {
+    StoreInfo->FtwLastWriteData = HobData;
+  }
+
+  if (VariableFvHeader != NULL) {
+    *VariableFvHeader = FvHeader;
+  }
+
+  //
+  // Check if the Firmware Volume is not corrupted
+  //
+  if ((FvHeader->Signature == EFI_FVH_SIGNATURE) &&
+      CompareGuid (&gEfiSystemNvDataFvGuid, &FvHeader->FileSystemGuid))
+  {
+    StoreHeader = (VARIABLE_STORE_HEADER *)((UINTN)FvHeader + FvHeader->HeaderLength);
+  } else {
+    StoreHeader = NULL;
+    DEBUG ((DEBUG_ERROR, "Firmware Volume for Variable Store is corrupted\n"));
+  }
+
+  if (StoreInfo != NULL) {
+    StoreInfo->VariableStoreHeader = StoreHeader;
+    if (StoreHeader != NULL) {
+      StoreInfo->AuthFlag = CompareGuid (
+                              &StoreHeader->Signature,
+                              &gEfiAuthenticatedVariableGuid
+                              );
+    }
+  }
+}
+
+/**
+  Return the variable store header and the store info based on the Index.
+
+  @param[in]  Type       The type of the variable store.
+  @param[out] StoreInfo  Return the store info.
+
+  @return  Pointer to the variable store header.
+**/
+VARIABLE_STORE_HEADER *
+GetVariableStore (
+  IN VARIABLE_STORE_TYPE   Type,
+  OUT VARIABLE_STORE_INFO  *StoreInfo
+  )
+{
+  EFI_HOB_GUID_TYPE  *GuidHob;
+
+  StoreInfo->VariableStoreHeader = NULL;
+  StoreInfo->IndexTable          = NULL;
+  StoreInfo->FtwLastWriteData    = NULL;
+  StoreInfo->AuthFlag            = FALSE;
+  switch (Type) {
+    case VariableStoreTypeHob:
+      GetHobVariableStore (StoreInfo);
+      break;
+
+    case VariableStoreTypeNv:
+      if (!PcdGetBool (PcdEmuVariableNvModeEnable)) {
+        //
+        // Emulated non-volatile variable mode is not enabled.
+        //
+        GetNvVariableStore (StoreInfo, NULL);
+        if (StoreInfo->VariableStoreHeader != NULL) {
+          GuidHob = GetFirstGuidHob (&gEfiVariableIndexTableGuid);
+          if (GuidHob != NULL) {
+            StoreInfo->IndexTable = GET_GUID_HOB_DATA (GuidHob);
+          } else {
+            //
+            // If it's the first time to access variable region in flash, create a guid hob to record
+            // VAR_ADDED type variable info.
+            // Note that as the resource of PEI phase is limited, only store the limited number of
+            // VAR_ADDED type variables to reduce access time.
+            //
+            StoreInfo->IndexTable              = (VARIABLE_INDEX_TABLE *)BuildGuidHob (&gEfiVariableIndexTableGuid, sizeof (VARIABLE_INDEX_TABLE));
+            StoreInfo->IndexTable->Length      = 0;
+            StoreInfo->IndexTable->StartPtr    = GetStartPointer (StoreInfo->VariableStoreHeader);
+            StoreInfo->IndexTable->EndPtr      = GetEndPointer (StoreInfo->VariableStoreHeader);
+            StoreInfo->IndexTable->GoneThrough = 0;
+          }
+        }
+      }
+
+      break;
+
+    default:
+      ASSERT (FALSE);
+      break;
+  }
+
+  return StoreInfo->VariableStoreHeader;
+}
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 09/28] MdeModulePkg: Add support for Protected Variables
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (7 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 08/28] MdeModulePkg: Add new Variable functionality Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-22 14:03   ` Wang, Jian J
  2022-04-29 18:04 ` [Patch v2 10/28] SecurityPkg: Add new KeyService types and defines Judah Vang
                   ` (20 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Liming Gao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add support for Protected Variables.
Add new API to retrieve Variable Infomation and data.
Add new API to update variable in non-volatile storage or
cached copy.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf    |    3 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf           |    3 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.inf |    4 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf  |    3 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h                |  126 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.h         |   91 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/Reclaim.c                 |  349 +++-
 MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c                | 2139 +++++++++++---------
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableDxe.c             |   26 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableExLib.c           |  167 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableNonVolatile.c     |  194 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.c         |  320 ++-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeCache.c    |    2 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c             |   39 +-
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.c   |   41 +-
 15 files changed, 2454 insertions(+), 1053 deletions(-)

diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf
index c9434df631ee..c0b90e6ca066 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf
@@ -9,7 +9,7 @@
 #  This external input must be validated carefully to avoid security issues such as
 #  buffer overflow or integer overflow.
 #
-# Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
+# Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
 # Copyright (c) Microsoft Corporation.
 # SPDX-License-Identifier: BSD-2-Clause-Patent
 #
@@ -73,6 +73,7 @@ [LibraryClasses]
   VarCheckLib
   VariablePolicyLib
   VariablePolicyHelperLib
+  ProtectedVariableLib
 
 [Protocols]
   gEfiFirmwareVolumeBlockProtocolGuid           ## CONSUMES
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf
index eaa97a01c6e5..6f9f027fbb0f 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf
@@ -18,7 +18,7 @@
 #  may not be modified without authorization. If platform fails to protect these resources,
 #  the authentication service provided in this driver will be broken, and the behavior is undefined.
 #
-# Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>
+# Copyright (c) 2010 - 2022, Intel Corporation. All rights reserved.<BR>
 # Copyright (c) Microsoft Corporation.
 # SPDX-License-Identifier: BSD-2-Clause-Patent
 #
@@ -82,6 +82,7 @@ [LibraryClasses]
   UefiBootServicesTableLib
   VariablePolicyLib
   VariablePolicyHelperLib
+  ProtectedVariableLib
 
 [Protocols]
   gEfiSmmFirmwareVolumeBlockProtocolGuid        ## CONSUMES
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.inf b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.inf
index a0d8b2267e92..5d2fc78ea917 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.inf
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.inf
@@ -13,7 +13,7 @@
 #  may not be modified without authorization. If platform fails to protect these resources,
 #  the authentication service provided in this driver will be broken, and the behavior is undefined.
 #
-# Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>
+# Copyright (c) 2010 - 2022, Intel Corporation. All rights reserved.<BR>
 # Copyright (c) Microsoft Corporation.<BR>
 # SPDX-License-Identifier: BSD-2-Clause-Patent
 #
@@ -61,6 +61,8 @@ [LibraryClasses]
   SafeIntLib
   PcdLib
   MmUnblockMemoryLib
+  ProtectedVariableLib
+  IoLib
 
 [Protocols]
   gEfiVariableWriteArchProtocolGuid             ## PRODUCES
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf
index d8c4f77e7f1f..6ea7b8d4293e 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf
@@ -18,7 +18,7 @@
 #  may not be modified without authorization. If platform fails to protect these resources,
 #  the authentication service provided in this driver will be broken, and the behavior is undefined.
 #
-# Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>
+# Copyright (c) 2010 - 2022, Intel Corporation. All rights reserved.<BR>
 # Copyright (c) 2018, Linaro, Ltd. All rights reserved.<BR>
 # Copyright (c) Microsoft Corporation.
 # SPDX-License-Identifier: BSD-2-Clause-Patent
@@ -78,6 +78,7 @@ [LibraryClasses]
   VarCheckLib
   VariablePolicyLib
   VariablePolicyHelperLib
+  ProtectedVariableLib
 
 [Protocols]
   gEfiSmmFirmwareVolumeBlockProtocolGuid        ## CONSUMES
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h
index 31e408976a35..97b4f9c906ff 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h
@@ -2,7 +2,7 @@
   The internal header file includes the common header files, defines
   internal structure and functions used by Variable modules.
 
-Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
@@ -31,6 +31,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 #include <Library/MemoryAllocationLib.h>
 #include <Library/AuthVariableLib.h>
 #include <Library/VarCheckLib.h>
+#include <Library/ProtectedVariableLib.h>
 #include <Guid/GlobalVariable.h>
 #include <Guid/EventGroup.h>
 #include <Guid/VariableFormat.h>
@@ -823,4 +824,127 @@ VariableExLibAtRuntime (
   VOID
   );
 
+/**
+  Is user variable?
+
+  @param[in] Variable   Pointer to variable header.
+
+  @retval TRUE          User variable.
+  @retval FALSE         System variable.
+
+**/
+BOOLEAN
+IsUserVariable (
+  IN VARIABLE_HEADER  *Variable
+  );
+
+/**
+
+  Variable store garbage collection and reclaim operation.
+
+  @param[in]      VariableBase            Base address of variable store.
+  @param[out]     LastVariableOffset      Offset of last variable.
+  @param[in]      IsVolatile              The variable store is volatile or not;
+                                          if it is non-volatile, need FTW.
+  @param[in, out] UpdatingPtrTrack        Pointer to updating variable pointer track structure.
+  @param[in]      NewVariable             Pointer to new variable.
+  @param[in]      NewVariableSize         New variable size.
+
+  @return EFI_SUCCESS                  Reclaim operation has finished successfully.
+  @return EFI_OUT_OF_RESOURCES         No enough memory resources or variable space.
+  @return Others                       Unexpect error happened during reclaim operation.
+
+**/
+EFI_STATUS
+Reclaim (
+  IN     EFI_PHYSICAL_ADDRESS    VariableBase,
+  OUT    UINTN                   *LastVariableOffset,
+  IN     BOOLEAN                 IsVolatile,
+  IN OUT VARIABLE_POINTER_TRACK  *UpdatingPtrTrack,
+  IN     VARIABLE_HEADER         *NewVariable,
+  IN     UINTN                   NewVariableSize
+  );
+
+/**
+
+  This function writes data to the FWH at the correct LBA even if the LBAs
+  are fragmented.
+
+  @param Global                  Pointer to VARIABLE_GLOBAL structure.
+  @param Volatile                Point out the Variable is Volatile or Non-Volatile.
+  @param SetByIndex              TRUE if target pointer is given as index.
+                                 FALSE if target pointer is absolute.
+  @param Fvb                     Pointer to the writable FVB protocol.
+  @param DataPtrIndex            Pointer to the Data from the end of VARIABLE_STORE_HEADER
+                                 structure.
+  @param DataSize                Size of data to be written.
+  @param Buffer                  Pointer to the buffer from which data is written.
+
+  @retval EFI_INVALID_PARAMETER  Parameters not valid.
+  @retval EFI_UNSUPPORTED        Fvb is a NULL for Non-Volatile variable update.
+  @retval EFI_OUT_OF_RESOURCES   The remaining size is not enough.
+  @retval EFI_SUCCESS            Variable store successfully updated.
+
+**/
+EFI_STATUS
+UpdateVariableStore (
+  IN VARIABLE_GLOBAL                     *Global,
+  IN BOOLEAN                             Volatile,
+  IN BOOLEAN                             SetByIndex,
+  IN EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *Fvb,
+  IN UINTN                               DataPtrIndex,
+  IN UINT32                              DataSize,
+  IN UINT8                               *Buffer
+  );
+
+/**
+  Update partial data of a variable on NV storage and/or cached copy.
+
+  @param[in]  VariableInfo  Pointer to a variable with detailed information.
+  @param[in]  Offset        Offset to write from.
+  @param[in]  Size          Size of data Buffer to update.
+  @param[in]  Buffer        Pointer to data buffer to update.
+
+  @retval EFI_SUCCESS             The variable data was updated successfully.
+  @retval EFI_UNSUPPORTED         If this function is called directly in runtime.
+  @retval EFI_INVALID_PARAMETER   If VariableInfo, Buffer or Size are not valid.
+  @retval Others                  Failed to update NV storage or variable cache.
+
+**/
+EFI_STATUS
+EFIAPI
+VariableExLibUpdateNvVariable (
+  IN  PROTECTED_VARIABLE_INFO  *VariableInfo,
+  IN  UINTN                    Offset,
+  IN  UINT32                   Size,
+  IN  UINT8                    *Buffer
+  );
+
+/**
+  Finds the given variable in a variable store in SMM.
+
+  Caution: This function may receive untrusted input.
+  The data size is external input, so this function will validate it carefully to avoid buffer overflow.
+
+  @param[in]      VariableName       Name of Variable to be found.
+  @param[in]      VendorGuid         Variable vendor GUID.
+  @param[out]     Attributes         Attribute value of the variable found.
+  @param[in, out] DataSize           Size of Data found. If size is less than the
+                                     data, this value contains the required size.
+  @param[out]     Data               Data pointer.
+
+  @retval EFI_SUCCESS                Found the specified variable.
+  @retval EFI_INVALID_PARAMETER      Invalid parameter.
+  @retval EFI_NOT_FOUND              The specified variable could not be found.
+
+**/
+EFI_STATUS
+FindVariableInSmm (
+  IN      CHAR16    *VariableName,
+  IN      EFI_GUID  *VendorGuid,
+  OUT     UINT32    *Attributes OPTIONAL,
+  IN OUT  UINTN     *DataSize,
+  OUT     VOID      *Data OPTIONAL
+  );
+
 #endif
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.h b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.h
index 951e8a089e34..3a4e8019aaf9 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.h
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.h
@@ -2,7 +2,7 @@
   Functions in this module are associated with variable parsing operations and
   are intended to be usable across variable driver source files.
 
-Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2019 - 2022, Intel Corporation. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
@@ -19,6 +19,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 
   @param[in] Variable           Pointer to the Variable Header.
   @param[in] VariableStoreEnd   Pointer to the Variable Store End.
+  @param[in] AuthFormat         Auth-variable indicator.
 
   @retval TRUE              Variable header is valid.
   @retval FALSE             Variable header is not valid.
@@ -27,7 +28,8 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 BOOLEAN
 IsValidVariableHeader (
   IN  VARIABLE_HEADER  *Variable,
-  IN  VARIABLE_HEADER  *VariableStoreEnd
+  IN  VARIABLE_HEADER  *VariableStoreEnd,
+  IN  BOOLEAN          AuthFormat
   );
 
 /**
@@ -192,6 +194,28 @@ GetVariableDataOffset (
   IN  BOOLEAN          AuthFormat
   );
 
+/**
+  Get variable data payload.
+
+  @param[in]      Variable     Pointer to the Variable Header.
+  @param[out]     Data         Pointer to buffer used to store the variable data.
+  @param[in]      DataSize     Size of buffer passed by Data.
+  @param[out]     DataSize     Size of data copied into Data buffer.
+  @param[in]      AuthFlag     Auth-variable indicator.
+
+  @return EFI_SUCCESS             Data was fetched.
+  @return EFI_INVALID_PARAMETER   DataSize is NULL.
+  @return EFI_BUFFER_TOO_SMALL    DataSize is smaller than size of variable data.
+
+**/
+EFI_STATUS
+GetVariableData (
+  IN      VARIABLE_HEADER  *Variable,
+  IN  OUT VOID             *Data,
+  IN  OUT UINT32           *DataSize,
+  IN      BOOLEAN          AuthFlag
+  );
+
 /**
 
   This code gets the pointer to the next variable header.
@@ -344,4 +368,67 @@ UpdateVariableInfo (
   IN OUT VARIABLE_INFO_ENTRY  **VariableInfo
   );
 
+/**
+
+  Retrieve details of the variable next to given variable within VariableStore.
+
+  If VarInfo->Address is NULL, the first one in VariableStore is returned.
+
+  VariableStart and/or VariableEnd can be given optionally for the situation
+  in which the valid storage space is smaller than the VariableStore->Size.
+  This usually happens when PEI variable services make a compact variable
+  cache to save memory, which cannot make use VariableStore->Size to determine
+  the correct variable storage range.
+
+  @param VariableStore            Pointer to a variable storage. It's optional.
+  @param VariableStart            Start point of valid range in VariableStore.
+  @param VariableEnd              End point of valid range in VariableStore.
+  @param VariableInfo             Pointer to variable information.
+
+  @retval EFI_INVALID_PARAMETER  VariableInfo or VariableStore is NULL.
+  @retval EFI_NOT_FOUND          If the end of VariableStore is reached.
+  @retval EFI_SUCCESS            The next variable is retrieved successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+GetNextVariableInfo (
+  IN OUT  PROTECTED_VARIABLE_INFO  *VarInfo
+  );
+
+/**
+
+  Retrieve details about a variable and return them in VariableInfo->Header.
+
+  If VariableInfo->Address is given, this function will calculate its offset
+  relative to given variable storage via VariableStore; Otherwise, it will try
+  other internal variable storages or cached copies. It's assumed that, for all
+  copies of NV variable storage, all variables are stored in the same relative
+  position. If VariableInfo->Address is found in the range of any storage copies,
+  its offset relative to that storage should be the same in other copies.
+
+  If VariableInfo->Offset is given (non-zero) but not VariableInfo->Address,
+  this function will return the variable memory address inside VariableStore,
+  if given, via VariableInfo->Address; Otherwise, the address of other storage
+  copies will be returned, if any.
+
+  For a new variable whose offset has not been determined, a value of -1 as
+  VariableInfo->Offset should be passed to skip the offset calculation.
+
+  @param VariableStore            Pointer to a variable storage. It's optional.
+  @param VariableInfo             Pointer to variable information.
+
+  @retval EFI_INVALID_PARAMETER  VariableInfo is NULL or both VariableInfo->Address
+                                 and VariableInfo->Offset are NULL (0).
+  @retval EFI_NOT_FOUND          If given Address or Offset is out of range of
+                                 any given or internal storage copies.
+  @retval EFI_SUCCESS            Variable details are retrieved successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+GetVariableInfo (
+  IN OUT  PROTECTED_VARIABLE_INFO  *VarInfo
+  );
+
 #endif
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/Reclaim.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/Reclaim.c
index fe64d0a2b3dd..a5b7f8a1fbe2 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/Reclaim.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/Reclaim.c
@@ -2,12 +2,15 @@
   Handles non-volatile variable store garbage collection, using FTW
   (Fault Tolerant Write) protocol.
 
-Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
 #include "Variable.h"
+#include "VariableNonVolatile.h"
+#include "VariableParsing.h"
+#include "VariableRuntimeCache.h"
 
 /**
   Gets LBA of block and offset by given address.
@@ -155,3 +158,347 @@ FtwVariableSpace (
 
   return Status;
 }
+
+/**
+
+  Variable store garbage collection and reclaim operation.
+
+  @param[in]      VariableBase            Base address of variable store.
+  @param[out]     LastVariableOffset      Offset of last variable.
+  @param[in]      IsVolatile              The variable store is volatile or not;
+                                          if it is non-volatile, need FTW.
+  @param[in, out] UpdatingPtrTrack        Pointer to updating variable pointer track structure.
+  @param[in]      NewVariable             Pointer to new variable.
+  @param[in]      NewVariableSize         New variable size.
+
+  @return EFI_SUCCESS                  Reclaim operation has finished successfully.
+  @return EFI_OUT_OF_RESOURCES         No enough memory resources or variable space.
+  @return Others                       Unexpect error happened during reclaim operation.
+
+**/
+EFI_STATUS
+Reclaim (
+  IN     EFI_PHYSICAL_ADDRESS    VariableBase,
+  OUT    UINTN                   *LastVariableOffset,
+  IN     BOOLEAN                 IsVolatile,
+  IN OUT VARIABLE_POINTER_TRACK  *UpdatingPtrTrack,
+  IN     VARIABLE_HEADER         *NewVariable,
+  IN     UINTN                   NewVariableSize
+  )
+{
+  VARIABLE_HEADER        *Variable;
+  VARIABLE_HEADER        *AddedVariable;
+  VARIABLE_HEADER        *NextVariable;
+  VARIABLE_HEADER        *NextAddedVariable;
+  VARIABLE_STORE_HEADER  *VariableStoreHeader;
+  UINT8                  *ValidBuffer;
+  UINTN                  MaximumBufferSize;
+  UINTN                  VariableSize;
+  UINTN                  NameSize;
+  UINT8                  *CurrPtr;
+  VOID                   *Point0;
+  VOID                   *Point1;
+  BOOLEAN                FoundAdded;
+  EFI_STATUS             Status;
+  EFI_STATUS             DoneStatus;
+  UINTN                  CommonVariableTotalSize;
+  UINTN                  CommonUserVariableTotalSize;
+  UINTN                  HwErrVariableTotalSize;
+  VARIABLE_HEADER        *UpdatingVariable;
+  VARIABLE_HEADER        *UpdatingInDeletedTransition;
+  BOOLEAN                AuthFormat;
+
+  AuthFormat                  = mVariableModuleGlobal->VariableGlobal.AuthFormat;
+  UpdatingVariable            = NULL;
+  UpdatingInDeletedTransition = NULL;
+  if (UpdatingPtrTrack != NULL) {
+    UpdatingVariable            = UpdatingPtrTrack->CurrPtr;
+    UpdatingInDeletedTransition = UpdatingPtrTrack->InDeletedTransitionPtr;
+  }
+
+  VariableStoreHeader = (VARIABLE_STORE_HEADER *)((UINTN)VariableBase);
+
+  CommonVariableTotalSize     = 0;
+  CommonUserVariableTotalSize = 0;
+  HwErrVariableTotalSize      = 0;
+
+  if (IsVolatile || mVariableModuleGlobal->VariableGlobal.EmuNvMode) {
+    //
+    // Start Pointers for the variable.
+    //
+    Variable          = GetStartPointer (VariableStoreHeader);
+    MaximumBufferSize = sizeof (VARIABLE_STORE_HEADER);
+
+    while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader), AuthFormat)) {
+      NextVariable = GetNextVariablePtr (Variable, AuthFormat);
+      if (((Variable->State == VAR_ADDED) || (Variable->State == (VAR_IN_DELETED_TRANSITION & VAR_ADDED))) &&
+          (Variable != UpdatingVariable) &&
+          (Variable != UpdatingInDeletedTransition)
+          )
+      {
+        VariableSize       = (UINTN)NextVariable - (UINTN)Variable;
+        MaximumBufferSize += VariableSize;
+      }
+
+      Variable = NextVariable;
+    }
+
+    if (NewVariable != NULL) {
+      //
+      // Add the new variable size.
+      //
+      MaximumBufferSize += NewVariableSize;
+    }
+
+    //
+    // Reserve the 1 Bytes with Oxff to identify the
+    // end of the variable buffer.
+    //
+    MaximumBufferSize += 1;
+    ValidBuffer        = AllocatePool (MaximumBufferSize);
+    if (ValidBuffer == NULL) {
+      return EFI_OUT_OF_RESOURCES;
+    }
+  } else {
+    //
+    // For NV variable reclaim, don't allocate pool here and just use mNvVariableCache
+    // as the buffer to reduce SMRAM consumption for SMM variable driver.
+    //
+    MaximumBufferSize = mNvVariableCache->Size;
+    ValidBuffer       = (UINT8 *)mNvVariableCache;
+  }
+
+  SetMem (ValidBuffer, MaximumBufferSize, 0xff);
+
+  //
+  // Copy variable store header.
+  //
+  CopyMem (ValidBuffer, VariableStoreHeader, sizeof (VARIABLE_STORE_HEADER));
+  CurrPtr = (UINT8 *)GetStartPointer ((VARIABLE_STORE_HEADER *)ValidBuffer);
+
+  //
+  // Reinstall all ADDED variables as long as they are not identical to Updating Variable.
+  //
+  Variable = GetStartPointer (VariableStoreHeader);
+  while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader), AuthFormat)) {
+    NextVariable = GetNextVariablePtr (Variable, AuthFormat);
+    if ((Variable != UpdatingVariable) && (Variable->State == VAR_ADDED)) {
+      VariableSize = (UINTN)NextVariable - (UINTN)Variable;
+      CopyMem (CurrPtr, (UINT8 *)Variable, VariableSize);
+      if (!IsVolatile) {
+        (VOID)ProtectedVariableLibRefresh (
+                (VARIABLE_HEADER *)CurrPtr,
+                VariableSize,
+                (UINTN)CurrPtr - (UINTN)ValidBuffer,
+                FALSE
+                );
+
+        if ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD)
+            == EFI_VARIABLE_HARDWARE_ERROR_RECORD)
+        {
+          HwErrVariableTotalSize += VariableSize;
+        } else {
+          CommonVariableTotalSize += VariableSize;
+          if (IsUserVariable (Variable)) {
+            CommonUserVariableTotalSize += VariableSize;
+          }
+        }
+      }
+
+      CurrPtr += VariableSize;
+    }
+
+    Variable = NextVariable;
+  }
+
+  //
+  // Reinstall all in delete transition variables.
+  //
+  Variable = GetStartPointer (VariableStoreHeader);
+  while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader), AuthFormat)) {
+    NextVariable = GetNextVariablePtr (Variable, AuthFormat);
+    if ((Variable != UpdatingVariable) && (Variable != UpdatingInDeletedTransition) && (Variable->State == (VAR_IN_DELETED_TRANSITION & VAR_ADDED)) &&
+        (ProtectedVariableLibIsHmac (GetVariableNamePtr (Variable, AuthFormat)) == FALSE))
+    {
+      FoundAdded    = FALSE;
+      AddedVariable = GetStartPointer ((VARIABLE_STORE_HEADER *)ValidBuffer);
+      while (IsValidVariableHeader (AddedVariable, GetEndPointer ((VARIABLE_STORE_HEADER *)ValidBuffer), AuthFormat)) {
+        NextAddedVariable = GetNextVariablePtr (AddedVariable, AuthFormat);
+        NameSize          = NameSizeOfVariable (AddedVariable, AuthFormat);
+        if (CompareGuid (
+              GetVendorGuidPtr (AddedVariable, AuthFormat),
+              GetVendorGuidPtr (Variable, AuthFormat)
+              ) && (NameSize == NameSizeOfVariable (Variable, AuthFormat)))
+        {
+          Point0 = (VOID *)GetVariableNamePtr (AddedVariable, AuthFormat);
+          Point1 = (VOID *)GetVariableNamePtr (Variable, AuthFormat);
+          if (CompareMem (Point0, Point1, NameSize) == 0) {
+            FoundAdded = TRUE;
+            break;
+          }
+        }
+
+        AddedVariable = NextAddedVariable;
+      }
+
+      if (!FoundAdded) {
+        //
+        // Promote VAR_IN_DELETED_TRANSITION to VAR_ADDED.
+        //
+        VariableSize = (UINTN)NextVariable - (UINTN)Variable;
+        CopyMem (CurrPtr, (UINT8 *)Variable, VariableSize);
+        ((VARIABLE_HEADER *)CurrPtr)->State = VAR_ADDED;
+        if (!IsVolatile) {
+          (VOID)ProtectedVariableLibRefresh (
+                  (VARIABLE_HEADER *)CurrPtr,
+                  VariableSize,
+                  (UINTN)CurrPtr - (UINTN)ValidBuffer,
+                  FALSE
+                  );
+
+          if ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD)
+              == EFI_VARIABLE_HARDWARE_ERROR_RECORD)
+          {
+            HwErrVariableTotalSize += VariableSize;
+          } else {
+            CommonVariableTotalSize += VariableSize;
+            if (IsUserVariable (Variable)) {
+              CommonUserVariableTotalSize += VariableSize;
+            }
+          }
+        }
+
+        CurrPtr += VariableSize;
+      }
+    }
+
+    Variable = NextVariable;
+  }
+
+  //
+  // Install the new variable if it is not NULL.
+  //
+  if (NewVariable != NULL) {
+    if (((UINTN)CurrPtr - (UINTN)ValidBuffer) + NewVariableSize > VariableStoreHeader->Size) {
+      //
+      // No enough space to store the new variable.
+      //
+      Status = EFI_OUT_OF_RESOURCES;
+      goto Done;
+    }
+
+    if (!IsVolatile) {
+      if ((NewVariable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) == EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
+        HwErrVariableTotalSize += NewVariableSize;
+      } else if ((NewVariable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) != EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
+        CommonVariableTotalSize += NewVariableSize;
+        if (IsUserVariable (NewVariable)) {
+          CommonUserVariableTotalSize += NewVariableSize;
+        }
+      }
+
+      if ((HwErrVariableTotalSize > PcdGet32 (PcdHwErrStorageSize)) ||
+          (CommonVariableTotalSize > mVariableModuleGlobal->CommonVariableSpace) ||
+          (CommonUserVariableTotalSize > mVariableModuleGlobal->CommonMaxUserVariableSpace))
+      {
+        //
+        // No enough space to store the new variable by NV or NV+HR attribute.
+        //
+        Status = EFI_OUT_OF_RESOURCES;
+        goto Done;
+      }
+    }
+
+    CopyMem (CurrPtr, (UINT8 *)NewVariable, NewVariableSize);
+    ((VARIABLE_HEADER *)CurrPtr)->State = VAR_ADDED;
+    if (UpdatingVariable != NULL) {
+      UpdatingPtrTrack->CurrPtr                = (VARIABLE_HEADER *)((UINTN)UpdatingPtrTrack->StartPtr + ((UINTN)CurrPtr - (UINTN)GetStartPointer ((VARIABLE_STORE_HEADER *)ValidBuffer)));
+      UpdatingPtrTrack->InDeletedTransitionPtr = NULL;
+    }
+
+    CurrPtr += NewVariableSize;
+  }
+
+  if (IsVolatile || mVariableModuleGlobal->VariableGlobal.EmuNvMode) {
+    //
+    // If volatile/emulated non-volatile variable store, just copy valid buffer.
+    //
+    SetMem ((UINT8 *)(UINTN)VariableBase, VariableStoreHeader->Size, 0xff);
+    CopyMem ((UINT8 *)(UINTN)VariableBase, ValidBuffer, (UINTN)CurrPtr - (UINTN)ValidBuffer);
+    *LastVariableOffset = (UINTN)CurrPtr - (UINTN)ValidBuffer;
+    if (!IsVolatile) {
+      //
+      // Emulated non-volatile variable mode.
+      //
+      mVariableModuleGlobal->HwErrVariableTotalSize      = HwErrVariableTotalSize;
+      mVariableModuleGlobal->CommonVariableTotalSize     = CommonVariableTotalSize;
+      mVariableModuleGlobal->CommonUserVariableTotalSize = CommonUserVariableTotalSize;
+    }
+
+    Status = EFI_SUCCESS;
+  } else {
+    //
+    // If non-volatile variable store, perform FTW here.
+    //
+    Status = FtwVariableSpace (
+               VariableBase,
+               (VARIABLE_STORE_HEADER *)ValidBuffer
+               );
+    if (!EFI_ERROR (Status)) {
+      *LastVariableOffset                                = (UINTN)CurrPtr - (UINTN)ValidBuffer;
+      mVariableModuleGlobal->HwErrVariableTotalSize      = HwErrVariableTotalSize;
+      mVariableModuleGlobal->CommonVariableTotalSize     = CommonVariableTotalSize;
+      mVariableModuleGlobal->CommonUserVariableTotalSize = CommonUserVariableTotalSize;
+    } else {
+      mVariableModuleGlobal->HwErrVariableTotalSize      = 0;
+      mVariableModuleGlobal->CommonVariableTotalSize     = 0;
+      mVariableModuleGlobal->CommonUserVariableTotalSize = 0;
+      Variable                                           = GetStartPointer ((VARIABLE_STORE_HEADER *)(UINTN)VariableBase);
+      while (IsValidVariableHeader (Variable, GetEndPointer ((VARIABLE_STORE_HEADER *)(UINTN)VariableBase), AuthFormat)) {
+        NextVariable = GetNextVariablePtr (Variable, AuthFormat);
+        VariableSize = (UINTN)NextVariable - (UINTN)Variable;
+        if ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) == EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
+          mVariableModuleGlobal->HwErrVariableTotalSize += VariableSize;
+        } else if ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) != EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
+          mVariableModuleGlobal->CommonVariableTotalSize += VariableSize;
+          if (IsUserVariable (Variable)) {
+            mVariableModuleGlobal->CommonUserVariableTotalSize += VariableSize;
+          }
+        }
+
+        Variable = NextVariable;
+      }
+
+      *LastVariableOffset = (UINTN)Variable - (UINTN)VariableBase;
+    }
+  }
+
+Done:
+  DoneStatus = EFI_SUCCESS;
+  if (IsVolatile || mVariableModuleGlobal->VariableGlobal.EmuNvMode) {
+    DoneStatus = SynchronizeRuntimeVariableCache (
+                   &mVariableModuleGlobal->VariableGlobal.VariableRuntimeCacheContext.VariableRuntimeVolatileCache,
+                   0,
+                   VariableStoreHeader->Size
+                   );
+    ASSERT_EFI_ERROR (DoneStatus);
+    FreePool (ValidBuffer);
+  } else {
+    //
+    // For NV variable reclaim, we use mNvVariableCache as the buffer, so copy the data back.
+    //
+    CopyMem (mNvVariableCache, (UINT8 *)(UINTN)VariableBase, VariableStoreHeader->Size);
+    DoneStatus = SynchronizeRuntimeVariableCache (
+                   &mVariableModuleGlobal->VariableGlobal.VariableRuntimeCacheContext.VariableRuntimeNvCache,
+                   0,
+                   VariableStoreHeader->Size
+                   );
+    ASSERT_EFI_ERROR (DoneStatus);
+  }
+
+  if (!EFI_ERROR (Status) && EFI_ERROR (DoneStatus)) {
+    Status = DoneStatus;
+  }
+
+  return Status;
+}
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
index 6c1a3440ac8c..6e86099eb72b 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
@@ -16,7 +16,7 @@
   VariableServiceSetVariable() should also check authenticate data to avoid buffer overflow,
   integer overflow. It should also check attribute to avoid authentication bypass.
 
-Copyright (c) 2006 - 2020, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
 (C) Copyright 2015-2018 Hewlett Packard Enterprise Development LP<BR>
 Copyright (c) Microsoft Corporation.<BR>
 Copyright (c) 2022, ARM Limited. All rights reserved.<BR>
@@ -30,7 +30,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 #include "VariableParsing.h"
 #include "VariableRuntimeCache.h"
 
-VARIABLE_MODULE_GLOBAL  *mVariableModuleGlobal;
+VARIABLE_MODULE_GLOBAL  *mVariableModuleGlobal = NULL;
 
 ///
 /// Define a memory cache that improves the search performance for a variable.
@@ -458,7 +458,7 @@ CalculateCommonUserVariableTotalSize (
   //
   if (mEndOfDxe && (mVariableModuleGlobal->CommonMaxUserVariableSpace != mVariableModuleGlobal->CommonVariableSpace)) {
     Variable = GetStartPointer (mNvVariableCache);
-    while (IsValidVariableHeader (Variable, GetEndPointer (mNvVariableCache))) {
+    while (IsValidVariableHeader (Variable, GetEndPointer (mNvVariableCache), mVariableModuleGlobal->VariableGlobal.AuthFormat)) {
       NextVariable = GetNextVariablePtr (Variable, mVariableModuleGlobal->VariableGlobal.AuthFormat);
       VariableSize = (UINTN)NextVariable - (UINTN)Variable;
       if ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) != EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
@@ -497,330 +497,6 @@ InitializeVariableQuota (
   CalculateCommonUserVariableTotalSize ();
 }
 
-/**
-
-  Variable store garbage collection and reclaim operation.
-
-  @param[in]      VariableBase            Base address of variable store.
-  @param[out]     LastVariableOffset      Offset of last variable.
-  @param[in]      IsVolatile              The variable store is volatile or not;
-                                          if it is non-volatile, need FTW.
-  @param[in, out] UpdatingPtrTrack        Pointer to updating variable pointer track structure.
-  @param[in]      NewVariable             Pointer to new variable.
-  @param[in]      NewVariableSize         New variable size.
-
-  @return EFI_SUCCESS                  Reclaim operation has finished successfully.
-  @return EFI_OUT_OF_RESOURCES         No enough memory resources or variable space.
-  @return Others                       Unexpect error happened during reclaim operation.
-
-**/
-EFI_STATUS
-Reclaim (
-  IN     EFI_PHYSICAL_ADDRESS    VariableBase,
-  OUT    UINTN                   *LastVariableOffset,
-  IN     BOOLEAN                 IsVolatile,
-  IN OUT VARIABLE_POINTER_TRACK  *UpdatingPtrTrack,
-  IN     VARIABLE_HEADER         *NewVariable,
-  IN     UINTN                   NewVariableSize
-  )
-{
-  VARIABLE_HEADER        *Variable;
-  VARIABLE_HEADER        *AddedVariable;
-  VARIABLE_HEADER        *NextVariable;
-  VARIABLE_HEADER        *NextAddedVariable;
-  VARIABLE_STORE_HEADER  *VariableStoreHeader;
-  UINT8                  *ValidBuffer;
-  UINTN                  MaximumBufferSize;
-  UINTN                  VariableSize;
-  UINTN                  NameSize;
-  UINT8                  *CurrPtr;
-  VOID                   *Point0;
-  VOID                   *Point1;
-  BOOLEAN                FoundAdded;
-  EFI_STATUS             Status;
-  EFI_STATUS             DoneStatus;
-  UINTN                  CommonVariableTotalSize;
-  UINTN                  CommonUserVariableTotalSize;
-  UINTN                  HwErrVariableTotalSize;
-  VARIABLE_HEADER        *UpdatingVariable;
-  VARIABLE_HEADER        *UpdatingInDeletedTransition;
-  BOOLEAN                AuthFormat;
-
-  AuthFormat                  = mVariableModuleGlobal->VariableGlobal.AuthFormat;
-  UpdatingVariable            = NULL;
-  UpdatingInDeletedTransition = NULL;
-  if (UpdatingPtrTrack != NULL) {
-    UpdatingVariable            = UpdatingPtrTrack->CurrPtr;
-    UpdatingInDeletedTransition = UpdatingPtrTrack->InDeletedTransitionPtr;
-  }
-
-  VariableStoreHeader = (VARIABLE_STORE_HEADER *)((UINTN)VariableBase);
-
-  CommonVariableTotalSize     = 0;
-  CommonUserVariableTotalSize = 0;
-  HwErrVariableTotalSize      = 0;
-
-  if (IsVolatile || mVariableModuleGlobal->VariableGlobal.EmuNvMode) {
-    //
-    // Start Pointers for the variable.
-    //
-    Variable          = GetStartPointer (VariableStoreHeader);
-    MaximumBufferSize = sizeof (VARIABLE_STORE_HEADER);
-
-    while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader))) {
-      NextVariable = GetNextVariablePtr (Variable, AuthFormat);
-      if (((Variable->State == VAR_ADDED) || (Variable->State == (VAR_IN_DELETED_TRANSITION & VAR_ADDED))) &&
-          (Variable != UpdatingVariable) &&
-          (Variable != UpdatingInDeletedTransition)
-          )
-      {
-        VariableSize       = (UINTN)NextVariable - (UINTN)Variable;
-        MaximumBufferSize += VariableSize;
-      }
-
-      Variable = NextVariable;
-    }
-
-    if (NewVariable != NULL) {
-      //
-      // Add the new variable size.
-      //
-      MaximumBufferSize += NewVariableSize;
-    }
-
-    //
-    // Reserve the 1 Bytes with Oxff to identify the
-    // end of the variable buffer.
-    //
-    MaximumBufferSize += 1;
-    ValidBuffer        = AllocatePool (MaximumBufferSize);
-    if (ValidBuffer == NULL) {
-      return EFI_OUT_OF_RESOURCES;
-    }
-  } else {
-    //
-    // For NV variable reclaim, don't allocate pool here and just use mNvVariableCache
-    // as the buffer to reduce SMRAM consumption for SMM variable driver.
-    //
-    MaximumBufferSize = mNvVariableCache->Size;
-    ValidBuffer       = (UINT8 *)mNvVariableCache;
-  }
-
-  SetMem (ValidBuffer, MaximumBufferSize, 0xff);
-
-  //
-  // Copy variable store header.
-  //
-  CopyMem (ValidBuffer, VariableStoreHeader, sizeof (VARIABLE_STORE_HEADER));
-  CurrPtr = (UINT8 *)GetStartPointer ((VARIABLE_STORE_HEADER *)ValidBuffer);
-
-  //
-  // Reinstall all ADDED variables as long as they are not identical to Updating Variable.
-  //
-  Variable = GetStartPointer (VariableStoreHeader);
-  while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader))) {
-    NextVariable = GetNextVariablePtr (Variable, AuthFormat);
-    if ((Variable != UpdatingVariable) && (Variable->State == VAR_ADDED)) {
-      VariableSize = (UINTN)NextVariable - (UINTN)Variable;
-      CopyMem (CurrPtr, (UINT8 *)Variable, VariableSize);
-      CurrPtr += VariableSize;
-      if ((!IsVolatile) && ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) == EFI_VARIABLE_HARDWARE_ERROR_RECORD)) {
-        HwErrVariableTotalSize += VariableSize;
-      } else if ((!IsVolatile) && ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) != EFI_VARIABLE_HARDWARE_ERROR_RECORD)) {
-        CommonVariableTotalSize += VariableSize;
-        if (IsUserVariable (Variable)) {
-          CommonUserVariableTotalSize += VariableSize;
-        }
-      }
-    }
-
-    Variable = NextVariable;
-  }
-
-  //
-  // Reinstall all in delete transition variables.
-  //
-  Variable = GetStartPointer (VariableStoreHeader);
-  while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader))) {
-    NextVariable = GetNextVariablePtr (Variable, AuthFormat);
-    if ((Variable != UpdatingVariable) && (Variable != UpdatingInDeletedTransition) && (Variable->State == (VAR_IN_DELETED_TRANSITION & VAR_ADDED))) {
-      //
-      // Buffer has cached all ADDED variable.
-      // Per IN_DELETED variable, we have to guarantee that
-      // no ADDED one in previous buffer.
-      //
-
-      FoundAdded    = FALSE;
-      AddedVariable = GetStartPointer ((VARIABLE_STORE_HEADER *)ValidBuffer);
-      while (IsValidVariableHeader (AddedVariable, GetEndPointer ((VARIABLE_STORE_HEADER *)ValidBuffer))) {
-        NextAddedVariable = GetNextVariablePtr (AddedVariable, AuthFormat);
-        NameSize          = NameSizeOfVariable (AddedVariable, AuthFormat);
-        if (CompareGuid (
-              GetVendorGuidPtr (AddedVariable, AuthFormat),
-              GetVendorGuidPtr (Variable, AuthFormat)
-              ) && (NameSize == NameSizeOfVariable (Variable, AuthFormat)))
-        {
-          Point0 = (VOID *)GetVariableNamePtr (AddedVariable, AuthFormat);
-          Point1 = (VOID *)GetVariableNamePtr (Variable, AuthFormat);
-          if (CompareMem (Point0, Point1, NameSize) == 0) {
-            FoundAdded = TRUE;
-            break;
-          }
-        }
-
-        AddedVariable = NextAddedVariable;
-      }
-
-      if (!FoundAdded) {
-        //
-        // Promote VAR_IN_DELETED_TRANSITION to VAR_ADDED.
-        //
-        VariableSize = (UINTN)NextVariable - (UINTN)Variable;
-        CopyMem (CurrPtr, (UINT8 *)Variable, VariableSize);
-        ((VARIABLE_HEADER *)CurrPtr)->State = VAR_ADDED;
-        CurrPtr                            += VariableSize;
-        if ((!IsVolatile) && ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) == EFI_VARIABLE_HARDWARE_ERROR_RECORD)) {
-          HwErrVariableTotalSize += VariableSize;
-        } else if ((!IsVolatile) && ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) != EFI_VARIABLE_HARDWARE_ERROR_RECORD)) {
-          CommonVariableTotalSize += VariableSize;
-          if (IsUserVariable (Variable)) {
-            CommonUserVariableTotalSize += VariableSize;
-          }
-        }
-      }
-    }
-
-    Variable = NextVariable;
-  }
-
-  //
-  // Install the new variable if it is not NULL.
-  //
-  if (NewVariable != NULL) {
-    if (((UINTN)CurrPtr - (UINTN)ValidBuffer) + NewVariableSize > VariableStoreHeader->Size) {
-      //
-      // No enough space to store the new variable.
-      //
-      Status = EFI_OUT_OF_RESOURCES;
-      goto Done;
-    }
-
-    if (!IsVolatile) {
-      if ((NewVariable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) == EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
-        HwErrVariableTotalSize += NewVariableSize;
-      } else if ((NewVariable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) != EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
-        CommonVariableTotalSize += NewVariableSize;
-        if (IsUserVariable (NewVariable)) {
-          CommonUserVariableTotalSize += NewVariableSize;
-        }
-      }
-
-      if ((HwErrVariableTotalSize > PcdGet32 (PcdHwErrStorageSize)) ||
-          (CommonVariableTotalSize > mVariableModuleGlobal->CommonVariableSpace) ||
-          (CommonUserVariableTotalSize > mVariableModuleGlobal->CommonMaxUserVariableSpace))
-      {
-        //
-        // No enough space to store the new variable by NV or NV+HR attribute.
-        //
-        Status = EFI_OUT_OF_RESOURCES;
-        goto Done;
-      }
-    }
-
-    CopyMem (CurrPtr, (UINT8 *)NewVariable, NewVariableSize);
-    ((VARIABLE_HEADER *)CurrPtr)->State = VAR_ADDED;
-    if (UpdatingVariable != NULL) {
-      UpdatingPtrTrack->CurrPtr                = (VARIABLE_HEADER *)((UINTN)UpdatingPtrTrack->StartPtr + ((UINTN)CurrPtr - (UINTN)GetStartPointer ((VARIABLE_STORE_HEADER *)ValidBuffer)));
-      UpdatingPtrTrack->InDeletedTransitionPtr = NULL;
-    }
-
-    CurrPtr += NewVariableSize;
-  }
-
-  if (IsVolatile || mVariableModuleGlobal->VariableGlobal.EmuNvMode) {
-    //
-    // If volatile/emulated non-volatile variable store, just copy valid buffer.
-    //
-    SetMem ((UINT8 *)(UINTN)VariableBase, VariableStoreHeader->Size, 0xff);
-    CopyMem ((UINT8 *)(UINTN)VariableBase, ValidBuffer, (UINTN)CurrPtr - (UINTN)ValidBuffer);
-    *LastVariableOffset = (UINTN)CurrPtr - (UINTN)ValidBuffer;
-    if (!IsVolatile) {
-      //
-      // Emulated non-volatile variable mode.
-      //
-      mVariableModuleGlobal->HwErrVariableTotalSize      = HwErrVariableTotalSize;
-      mVariableModuleGlobal->CommonVariableTotalSize     = CommonVariableTotalSize;
-      mVariableModuleGlobal->CommonUserVariableTotalSize = CommonUserVariableTotalSize;
-    }
-
-    Status = EFI_SUCCESS;
-  } else {
-    //
-    // If non-volatile variable store, perform FTW here.
-    //
-    Status = FtwVariableSpace (
-               VariableBase,
-               (VARIABLE_STORE_HEADER *)ValidBuffer
-               );
-    if (!EFI_ERROR (Status)) {
-      *LastVariableOffset                                = (UINTN)CurrPtr - (UINTN)ValidBuffer;
-      mVariableModuleGlobal->HwErrVariableTotalSize      = HwErrVariableTotalSize;
-      mVariableModuleGlobal->CommonVariableTotalSize     = CommonVariableTotalSize;
-      mVariableModuleGlobal->CommonUserVariableTotalSize = CommonUserVariableTotalSize;
-    } else {
-      mVariableModuleGlobal->HwErrVariableTotalSize      = 0;
-      mVariableModuleGlobal->CommonVariableTotalSize     = 0;
-      mVariableModuleGlobal->CommonUserVariableTotalSize = 0;
-      Variable                                           = GetStartPointer ((VARIABLE_STORE_HEADER *)(UINTN)VariableBase);
-      while (IsValidVariableHeader (Variable, GetEndPointer ((VARIABLE_STORE_HEADER *)(UINTN)VariableBase))) {
-        NextVariable = GetNextVariablePtr (Variable, AuthFormat);
-        VariableSize = (UINTN)NextVariable - (UINTN)Variable;
-        if ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) == EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
-          mVariableModuleGlobal->HwErrVariableTotalSize += VariableSize;
-        } else if ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) != EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
-          mVariableModuleGlobal->CommonVariableTotalSize += VariableSize;
-          if (IsUserVariable (Variable)) {
-            mVariableModuleGlobal->CommonUserVariableTotalSize += VariableSize;
-          }
-        }
-
-        Variable = NextVariable;
-      }
-
-      *LastVariableOffset = (UINTN)Variable - (UINTN)VariableBase;
-    }
-  }
-
-Done:
-  DoneStatus = EFI_SUCCESS;
-  if (IsVolatile || mVariableModuleGlobal->VariableGlobal.EmuNvMode) {
-    DoneStatus = SynchronizeRuntimeVariableCache (
-                   &mVariableModuleGlobal->VariableGlobal.VariableRuntimeCacheContext.VariableRuntimeVolatileCache,
-                   0,
-                   VariableStoreHeader->Size
-                   );
-    ASSERT_EFI_ERROR (DoneStatus);
-    FreePool (ValidBuffer);
-  } else {
-    //
-    // For NV variable reclaim, we use mNvVariableCache as the buffer, so copy the data back.
-    //
-    CopyMem (mNvVariableCache, (UINT8 *)(UINTN)VariableBase, VariableStoreHeader->Size);
-    DoneStatus = SynchronizeRuntimeVariableCache (
-                   &mVariableModuleGlobal->VariableGlobal.VariableRuntimeCacheContext.VariableRuntimeNvCache,
-                   0,
-                   VariableStoreHeader->Size
-                   );
-    ASSERT_EFI_ERROR (DoneStatus);
-  }
-
-  if (!EFI_ERROR (Status) && EFI_ERROR (DoneStatus)) {
-    Status = DoneStatus;
-  }
-
-  return Status;
-}
-
 /**
   Finds variable in storage blocks of volatile and non-volatile storage areas.
 
@@ -1657,9 +1333,665 @@ AutoUpdateLangVariable (
 }
 
 /**
-  Update the variable region with Variable information. If EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS is set,
-  index of associated public key is needed.
+  Check if there's enough free space in storage to write the new variable.
 
+  @param[in] NewVariable        Pointer to buffer of new variable.
+  @param[in] VariableSize       Size of new variable.
+  @param[in] VariableName       Name of variable.
+  @param[in] VendorGuid         Guid of variable.
+  @param[in] Attributes         Attributes of the variable.
+  @param[in] VolatileFlag       Volatile/non-volatile variable indicator.
+
+  @retval EFI_SUCCESS           Enough free space on variable storage.
+  @retval EFI_BUFFER_TOO_SMALL  There's not enough continuous free space.
+  @retval EFI_OUT_OF_RESOURCES  There's not enough free space in total.
+**/
+EFI_STATUS
+CheckVariableStoreSpace (
+  IN  VARIABLE_HEADER  *NewVariable,
+  IN  UINTN            VariableSize,
+  IN  CHAR16           *VariableName,
+  IN  EFI_GUID         *VendorGuid,
+  IN  UINT32           Attributes,
+  IN  BOOLEAN          VolatileFlag
+  )
+{
+  BOOLEAN                IsCommonVariable;
+  BOOLEAN                IsCommonUserVariable;
+  UINTN                  CommonVariableTotalSize;
+  UINTN                  CommonUserVariableTotalSize;
+  UINTN                  HwErrVariableTotalSize;
+  VARIABLE_STORE_HEADER  *VarStore;
+
+  if ((NewVariable == NULL) || (VariableSize == 0)) {
+    return EFI_SUCCESS;
+  }
+
+  if (VolatileFlag) {
+    VarStore = (VARIABLE_STORE_HEADER *)(UINTN)
+               mVariableModuleGlobal->VariableGlobal.VolatileVariableBase;
+    if ((UINT32)(VariableSize + mVariableModuleGlobal->VolatileLastVariableOffset)
+        > VarStore->Size)
+    {
+      return EFI_BUFFER_TOO_SMALL;
+    }
+  } else {
+    if ((Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) == 0) {
+      IsCommonVariable     = TRUE;
+      IsCommonUserVariable = IsUserVariable (NewVariable);
+    } else {
+      IsCommonVariable     = FALSE;
+      IsCommonUserVariable = FALSE;
+    }
+
+    CommonVariableTotalSize     = mVariableModuleGlobal->CommonVariableTotalSize + VariableSize;
+    CommonUserVariableTotalSize = mVariableModuleGlobal->CommonUserVariableTotalSize + VariableSize;
+    HwErrVariableTotalSize      = mVariableModuleGlobal->HwErrVariableTotalSize + VariableSize;
+
+    if (  (((Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) != 0) &&
+           (HwErrVariableTotalSize > PcdGet32 (PcdHwErrStorageSize)))
+       || (IsCommonVariable && (CommonVariableTotalSize > mVariableModuleGlobal->CommonVariableSpace))
+       || (IsCommonVariable &&
+           AtRuntime () &&
+           (CommonVariableTotalSize > mVariableModuleGlobal->CommonRuntimeVariableSpace))
+       || (IsCommonUserVariable &&
+           (CommonUserVariableTotalSize > mVariableModuleGlobal->CommonMaxUserVariableSpace)))
+    {
+      if (AtRuntime ()) {
+        if (IsCommonUserVariable &&
+            ((VariableSize + mVariableModuleGlobal->CommonUserVariableTotalSize)
+             > mVariableModuleGlobal->CommonMaxUserVariableSpace))
+        {
+          RecordVarErrorFlag (
+            VAR_ERROR_FLAG_USER_ERROR,
+            VariableName,
+            VendorGuid,
+            Attributes,
+            VariableSize
+            );
+        }
+
+        if (IsCommonVariable &&
+            ((VariableSize + mVariableModuleGlobal->CommonVariableTotalSize)
+             > mVariableModuleGlobal->CommonRuntimeVariableSpace))
+        {
+          RecordVarErrorFlag (
+            VAR_ERROR_FLAG_SYSTEM_ERROR,
+            VariableName,
+            VendorGuid,
+            Attributes,
+            VariableSize
+            );
+        }
+
+        return EFI_OUT_OF_RESOURCES;
+      }
+
+      return EFI_BUFFER_TOO_SMALL;
+    }
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Fill specific data of auth-variable in buffer.
+
+  @param[in,out]  NewVariable        Pointer to buffer of new variable.
+  @param[in]      OldVariable        Pointer to buffer of old copy of the variable.
+  @param[in]      Attributes         Attributes of the variable.
+  @param[in]      KeyIndex           Index of associated public key.
+  @param[in]      MonotonicCount     Value of associated monotonic count.
+  @param[in]      TimeStamp          Value of associated TimeStamp.
+
+**/
+VOID
+SetVariableAuthData (
+  IN  OUT AUTHENTICATED_VARIABLE_HEADER  *NewVariable,
+  IN      AUTHENTICATED_VARIABLE_HEADER  *OldVariable,
+  IN      UINT32                         Attributes,
+  IN      UINT32                         KeyIndex,
+  IN      UINT64                         MonotonicCount,
+  IN      EFI_TIME                       *TimeStamp
+  )
+{
+  NewVariable->PubKeyIndex    = KeyIndex;
+  NewVariable->MonotonicCount = MonotonicCount;
+
+  if ((TimeStamp != NULL) &&
+      ((Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) != 0))
+  {
+    //
+    // In the case when the EFI_VARIABLE_APPEND_WRITE attribute is set, only
+    // when the new TimeStamp value is later than the current timestamp associated
+    // with the variable, we need associate the new timestamp with the updated value.
+    //
+    if (((Attributes & EFI_VARIABLE_APPEND_WRITE) != 0) &&
+        (OldVariable != NULL) &&
+        !VariableCompareTimeStampInternal (&OldVariable->TimeStamp, TimeStamp))
+    {
+      TimeStamp = &OldVariable->TimeStamp;
+    }
+
+    CopyMem (&NewVariable->TimeStamp, TimeStamp, sizeof (EFI_TIME));
+  } else {
+    ZeroMem (&NewVariable->TimeStamp, sizeof (EFI_TIME));
+  }
+}
+
+/**
+  Fill the variable data buffer according to variable format on storage.
+
+  @param[in,out]  NewVariable        Pointer to buffer of new variable.
+  @param[in]      OldVariable        Pointer to buffer of old copy of the variable.
+  @param[in]      VariableName       Name of variable.
+  @param[in]      VendorGuid         Guid of variable.
+  @param[in]      Data               Variable data.
+  @param[in]      DataSize           Size of data. 0 means delete.
+  @param[in]      Attributes         Attributes of the variable.
+  @param[in]      KeyIndex           Index of associated public key.
+  @param[in]      MonotonicCount     Value of associated monotonic count.
+  @param[in]      TimeStamp          Value of associated TimeStamp.
+
+  @retval Size of the new variable.
+
+**/
+UINTN
+SetVariableData (
+  IN  OUT VARIABLE_HEADER  *NewVariable,
+  IN      VARIABLE_HEADER  *OldVariable,
+  IN      CHAR16           *VariableName,
+  IN      EFI_GUID         *VendorGuid,
+  IN      VOID             *Data,
+  IN      UINTN            DataSize,
+  IN      UINT32           Attributes,
+  IN      UINT32           KeyIndex,
+  IN      UINT64           MonotonicCount,
+  IN      EFI_TIME         *TimeStamp
+  )
+{
+  EFI_STATUS  Status;
+  BOOLEAN     AuthFormat;
+  UINT8       *DataPtr;
+  UINTN       NameSize;
+  UINTN       OldDataSize;
+
+  AuthFormat = mVariableModuleGlobal->VariableGlobal.AuthFormat;
+
+  if (AuthFormat) {
+    SetVariableAuthData (
+      (AUTHENTICATED_VARIABLE_HEADER *)NewVariable,
+      (AUTHENTICATED_VARIABLE_HEADER *)OldVariable,
+      Attributes,
+      KeyIndex,
+      MonotonicCount,
+      TimeStamp
+      );
+  }
+
+  NewVariable->StartId    = VARIABLE_DATA;
+  NewVariable->State      = VAR_ADDED;
+  NewVariable->Reserved   = 0;
+  NewVariable->Attributes = Attributes & (~EFI_VARIABLE_APPEND_WRITE);
+
+  CopyMem (
+    GetVendorGuidPtr (NewVariable, AuthFormat),
+    VendorGuid,
+    sizeof (EFI_GUID)
+    );
+
+  NameSize = StrSize (VariableName);
+  SetNameSizeOfVariable (NewVariable, NameSize, AuthFormat);
+  CopyMem (
+    (UINT8 *)GetVariableNamePtr (NewVariable, AuthFormat),
+    VariableName,
+    NameSize
+    );
+
+  //
+  // Set data size first otherwise we can't get correct data pointer in the
+  // buffer of new variable.
+  //
+  SetDataSizeOfVariable (NewVariable, DataSize, AuthFormat);
+  DataPtr = GetVariableDataPtr (NewVariable, AuthFormat);
+  if (((Attributes & EFI_VARIABLE_APPEND_WRITE) != 0) &&
+      (OldVariable != NULL) &&
+      ((OldVariable->State == VAR_ADDED) ||
+       (OldVariable->State == (VAR_ADDED & VAR_IN_DELETED_TRANSITION))))
+  {
+    //
+    // Get old data, which might be encrypted.
+    //
+    OldDataSize = mVariableModuleGlobal->ScratchBufferSize
+                  - ((UINTN)DataPtr - (UINTN)NewVariable);
+    Status = ProtectedVariableLibGetByBuffer (
+               OldVariable,
+               DataPtr,
+               (UINT32 *)&OldDataSize,
+               AuthFormat
+               );
+    if (Status == EFI_UNSUPPORTED) {
+      OldDataSize = DataSizeOfVariable (OldVariable, AuthFormat);
+      CopyMem (DataPtr, GetVariableDataPtr (OldVariable, AuthFormat), OldDataSize);
+    } else if (EFI_ERROR (Status)) {
+      ASSERT_EFI_ERROR (Status);
+      return 0;
+    }
+
+    DataPtr += OldDataSize;
+    //
+    // Update data size.
+    //
+    SetDataSizeOfVariable (NewVariable, DataSize + OldDataSize, AuthFormat);
+  }
+
+  CopyMem (DataPtr, Data, DataSize);
+
+  //
+  // The actual size of the variable stored in storage should include padding.
+  //
+  return ((UINTN)GetNextVariablePtr (NewVariable, AuthFormat) - (UINTN)NewVariable);
+}
+
+/**
+  Update state of given variable as well as its cached copy.
+
+  @param[in,out]  Variable        Pointer to the buffer of the variable.
+  @param[in,out]  CacheVariable   Cache copy of the variable.
+  @param[in]      NewState        New state value.
+  @param[in]      Volatile        Volatile/non-volatile variable indicator.
+
+  @retval EFI_SUCCESS     Variable state was updated successfully.
+  @retval Others          Failed to update the variable state.
+
+**/
+EFI_STATUS
+UpdateVariableState (
+  IN  OUT VARIABLE_HEADER  *Variable,
+  IN  OUT VARIABLE_HEADER  *CacheVariable,
+  IN      UINT8            NewState,
+  IN      BOOLEAN          Volatile
+  )
+{
+  EFI_STATUS  Status;
+
+  Status = UpdateVariableStore (
+             &mVariableModuleGlobal->VariableGlobal,
+             Volatile,
+             FALSE,
+             mVariableModuleGlobal->FvbInstance,
+             (UINTN)&Variable->State,
+             sizeof (NewState),
+             &NewState
+             );
+  if (!EFI_ERROR (Status) && (CacheVariable != NULL)) {
+    CacheVariable->State = NewState;
+  }
+
+  return Status;
+}
+
+/**
+  Flush variable data to variable storage.
+
+  @param[in]      VarStoreBase    Base address of variable storage.
+  @param[in,out]  Offset          Offset to write the variable from.
+                                  Offset from where next variable can be written.
+  @param[in,out]  NewVariable     Pointer to the buffer of new variable.
+  @param[in]      VariableSize    Size of new variable.
+  @param[in]      Volatile        Volatile/non-volatile variable indicator.
+  @param[in]      AuthFormat      Auth-variable indicator.
+
+  @retval EFI_SUCCESS     Variable(s) were written successfully.
+  @retval Others          Failed to write the variable data.
+
+**/
+EFI_STATUS
+WriteVariable (
+  IN  EFI_PHYSICAL_ADDRESS  VarStoreBase,
+  IN  OUT UINTN             *Offset,
+  IN  OUT VARIABLE_HEADER   **NewVariable,
+  IN      UINT32            VariableSize,
+  IN      BOOLEAN           Volatile,
+  IN      BOOLEAN           AuthFormat
+  )
+{
+  EFI_STATUS  Status;
+
+  struct {
+    UINTN     Offset;
+    UINT8     *Buffer;
+    UINT32    Size;
+    UINT8     State;
+  }                   WriteSteps[4];
+  UINTN            Index;
+  UINTN            Steps;
+  VARIABLE_HEADER  *Variable;
+
+  Variable = *NewVariable;
+  if (Volatile) {
+    //
+    // For non-volatile variable, one step only :
+    //
+    WriteSteps[0].Offset = *Offset;
+    WriteSteps[0].Buffer = (UINT8 *)Variable;
+    WriteSteps[0].Size   = VariableSize;
+
+    Steps = 1;
+  } else {
+    //
+    // Four steps for non-volatile variable:
+    //
+    // 1. Write variable header
+    // 2. Set variable state to header valid
+    // 3. Write variable name and data
+    // 4. Set variable state to valid
+    //
+    Variable->State      = 0xff;
+    WriteSteps[0].Offset = *Offset;
+    WriteSteps[0].Buffer = (UINT8 *)Variable;
+    WriteSteps[0].Size   = (UINT32)GetVariableHeaderSize (AuthFormat);
+
+    WriteSteps[1].State  = VAR_HEADER_VALID_ONLY;
+    WriteSteps[1].Offset = *Offset + OFFSET_OF (VARIABLE_HEADER, State);
+    WriteSteps[1].Buffer = &WriteSteps[1].State;
+    WriteSteps[1].Size   = sizeof (Variable->State);
+
+    WriteSteps[2].Offset = *Offset + GetVariableHeaderSize (AuthFormat);
+    WriteSteps[2].Buffer = (UINT8 *)Variable + GetVariableHeaderSize (AuthFormat);
+    WriteSteps[2].Size   = VariableSize - (UINT32)GetVariableHeaderSize (AuthFormat);
+
+    WriteSteps[3].State  = VAR_ADDED;
+    WriteSteps[3].Offset = *Offset + OFFSET_OF (VARIABLE_HEADER, State);
+    WriteSteps[3].Buffer = &WriteSteps[3].State;
+    WriteSteps[3].Size   = sizeof (Variable->State);
+
+    Steps = ARRAY_SIZE (WriteSteps);
+  }
+
+  for (Index = 0; Index < Steps; ++Index) {
+    Status = UpdateVariableStore (
+               &mVariableModuleGlobal->VariableGlobal,
+               Volatile,
+               TRUE,
+               mVariableModuleGlobal->FvbInstance,
+               WriteSteps[Index].Offset,
+               WriteSteps[Index].Size,
+               WriteSteps[Index].Buffer
+               );
+    if (EFI_ERROR (Status)) {
+      ASSERT_EFI_ERROR (Status);
+      return Status;
+    }
+  }
+
+  Variable->State = VAR_ADDED;
+  if (!Volatile) {
+    CopyMem ((UINT8 *)mNvVariableCache + *Offset, Variable, VariableSize);
+  }
+
+  *NewVariable = (VARIABLE_HEADER *)((UINTN)VarStoreBase + *Offset);
+  *Offset     += HEADER_ALIGN (VariableSize);
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Rebase the given variable pointer(s) to the equivalent one in given variable
+  storage via VarStore.
+
+  @param[in]      InVarTrackPtr     Pointer to current variable in cache.
+  @param[out]     OutVarTrackPtr    Pointer to rebased variable against VarStore.
+  @param[in]      VarStore          Start of variable storage to rebase against.
+  @param[in]      VariableName      Name of variable.
+  @param[in]      VendorGuid        Guid of variable.
+  @param[in]      ByOffset          If TRUE, don't do variable search in VarStore.
+
+  @retval EFI_SUCCESS           Variable(s) were deleted successfully.
+  @retval EFI_INVALID_PARAMETER Invalid parameters passed.
+  @retval EFI_NOT_FOUND         Given variable (VariableName & VendorGuid) was
+                                not found in VarStore, if ByOffset is FALSE.
+
+**/
+EFI_STATUS
+RebaseVariablePtr (
+  IN      VARIABLE_POINTER_TRACK  *InVarTrackPtr,
+  OUT VARIABLE_POINTER_TRACK      *OutVarTrackPtr,
+  IN      VARIABLE_STORE_HEADER   *VarStore,
+  IN      CHAR16                  *VariableName,
+  IN      EFI_GUID                *VendorGuid,
+  IN      BOOLEAN                 ByOffset
+  )
+{
+  EFI_STATUS       Status;
+  BOOLEAN          AuthFormat;
+  VARIABLE_HEADER  *NewStart;
+
+  if ((InVarTrackPtr == NULL) || (OutVarTrackPtr == NULL) || (VarStore == NULL)) {
+    ASSERT (InVarTrackPtr != NULL);
+    ASSERT (OutVarTrackPtr != NULL);
+    ASSERT (VarStore != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  AuthFormat = mVariableModuleGlobal->VariableGlobal.AuthFormat;
+
+  if (  (InVarTrackPtr->CurrPtr == NULL)
+     || (InVarTrackPtr->StartPtr == GetStartPointer (VarStore)))
+  {
+    CopyMem (OutVarTrackPtr, InVarTrackPtr, sizeof (VARIABLE_POINTER_TRACK));
+    return EFI_SUCCESS;
+  }
+
+  NewStart = GetStartPointer (VarStore);
+  if (ByOffset) {
+    OutVarTrackPtr->CurrPtr = (VARIABLE_HEADER *)
+                              ((UINTN)NewStart + ((UINTN)InVarTrackPtr->CurrPtr -
+                                                  (UINTN)InVarTrackPtr->StartPtr));
+
+    if (InVarTrackPtr->InDeletedTransitionPtr != NULL) {
+      OutVarTrackPtr->InDeletedTransitionPtr =
+        (VARIABLE_HEADER *)((UINTN)NewStart +
+                            ((UINTN)InVarTrackPtr->InDeletedTransitionPtr -
+                             (UINTN)InVarTrackPtr->StartPtr));
+    } else {
+      OutVarTrackPtr->InDeletedTransitionPtr = NULL;
+    }
+
+    OutVarTrackPtr->StartPtr = NewStart;
+    OutVarTrackPtr->EndPtr   = GetEndPointer (VarStore);
+  } else {
+    OutVarTrackPtr->StartPtr = NewStart;
+    OutVarTrackPtr->EndPtr   = GetEndPointer (VarStore);
+
+    Status = FindVariableEx (VariableName, VendorGuid, FALSE, OutVarTrackPtr, AuthFormat);
+    if ((OutVarTrackPtr->CurrPtr == NULL) || EFI_ERROR (Status)) {
+      return EFI_NOT_FOUND;
+    }
+  }
+
+  if (  (VarStore == mNvVariableCache)
+     || ((UINTN)VarStore == (UINTN)mVariableModuleGlobal->VariableGlobal.NonVolatileVariableBase))
+  {
+    OutVarTrackPtr->Volatile = FALSE;
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Check if the given variable is from HOB.
+
+  @param[in] CacheVariable      Pointer to current variable in cache.
+
+  @retval TRUE    The variable is from HOB.
+  @retval FALSE   The variable is NOT from HOB.
+
+**/
+BOOLEAN
+IsHobVariable (
+  IN VARIABLE_POINTER_TRACK  *CacheVariable
+  )
+{
+  VARIABLE_STORE_HEADER  *HobVarStore;
+
+  HobVarStore = (VARIABLE_STORE_HEADER *)(UINTN)
+                mVariableModuleGlobal->VariableGlobal.HobVariableBase;
+  return (CacheVariable->CurrPtr != NULL &&
+          HobVarStore != NULL &&
+          CacheVariable->StartPtr == GetStartPointer (HobVarStore));
+}
+
+/**
+  Get temporary buffer for a new variable data.
+
+  @retval Pointer to the buffer address.
+
+**/
+VARIABLE_HEADER *
+GetNewVariableBuffer (
+  VOID
+  )
+{
+  VARIABLE_HEADER        *NewVariable;
+  VARIABLE_STORE_HEADER  *VarStore;
+
+  //
+  // Tricky part: Use scratch data area at the end of volatile variable store
+  // as a temporary storage.
+  //
+  VarStore = (VARIABLE_STORE_HEADER *)(UINTN)
+             mVariableModuleGlobal->VariableGlobal.VolatileVariableBase;
+  NewVariable = GetEndPointer (VarStore);
+
+  SetMem (NewVariable, mVariableModuleGlobal->ScratchBufferSize, 0xff);
+
+  return NewVariable;
+}
+
+/**
+  Delete old copies of variable completely.
+
+  @param[in]      VariableName       Name of variable.
+  @param[in]      VendorGuid         Guid of variable.
+  @param[in]      Variable           Pointer to current variable on storage.
+  @param[in,out]  CacheVariable      Pointer to current variable in cache.
+  @param[in]      VolatileFlag       Auth-variable indicator.
+
+  @retval EFI_SUCCESS           Variable(s) were deleted successfully.
+  @retval Others                Failed to update variable state.
+
+**/
+EFI_STATUS
+DeleteVariable (
+  IN      CHAR16                  *VariableName,
+  IN      EFI_GUID                *VendorGuid,
+  IN      VARIABLE_POINTER_TRACK  *Variable,
+  IN  OUT VARIABLE_POINTER_TRACK  *CacheVariable,
+  IN      BOOLEAN                 VolatileFlag
+  )
+{
+  EFI_STATUS  Status;
+
+  if (Variable->InDeletedTransitionPtr != NULL) {
+    ASSERT (CacheVariable->InDeletedTransitionPtr != NULL);
+    //
+    // Both ADDED and IN_DELETED_TRANSITION variable are present,
+    // set IN_DELETED_TRANSITION one to DELETED state first.
+    //
+    Status = UpdateVariableState (
+               Variable->InDeletedTransitionPtr,
+               CacheVariable->InDeletedTransitionPtr,
+               CacheVariable->InDeletedTransitionPtr->State & VAR_DELETED,
+               VolatileFlag
+               );
+    if (EFI_ERROR (Status)) {
+      return Status;
+    }
+  }
+
+  ASSERT (CacheVariable->CurrPtr != NULL);
+  Status = UpdateVariableState (
+             Variable->CurrPtr,
+             CacheVariable->CurrPtr,
+             CacheVariable->CurrPtr->State & VAR_DELETED,
+             VolatileFlag
+             );
+
+  if (!EFI_ERROR (Status)) {
+    UpdateVariableInfo (
+      VariableName,
+      VendorGuid,
+      Variable->Volatile,
+      FALSE,
+      FALSE,
+      TRUE,
+      FALSE,
+      &gVariableInfo
+      );
+    if (!Variable->Volatile) {
+      FlushHobVariableToFlash (VariableName, VendorGuid);
+    }
+  }
+
+  return Status;
+}
+
+/**
+  Check if it's the right time to update a variable.
+
+  @param[in] Attributes         Attributes of a variable.
+
+  @retval TRUE    It's ready for variable update.
+  @retval FALSE   It's NOT ready for variable update.
+
+**/
+BOOLEAN
+ReadyForUpdate (
+  IN UINT32  Attributes
+  )
+{
+  if ((mVariableModuleGlobal->FvbInstance == NULL) &&
+      !mVariableModuleGlobal->VariableGlobal.EmuNvMode)
+  {
+    //
+    // The FVB protocol is not ready, so the EFI_VARIABLE_WRITE_ARCH_PROTOCOL
+    // is not installed.
+    //
+    if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
+      //
+      // Trying to update NV variable prior to the installation of
+      // EFI_VARIABLE_WRITE_ARCH_PROTOCOL
+      //
+      DEBUG ((
+        DEBUG_ERROR,
+        "Update NV variable before EFI_VARIABLE_WRITE_ARCH_PROTOCOL ready - %r\n",
+        EFI_NOT_AVAILABLE_YET
+        ));
+      return FALSE;
+    } else if ((Attributes & VARIABLE_ATTRIBUTE_AT_AW) != 0) {
+      //
+      // Trying to update volatile authenticated variable prior to the
+      // installation of EFI_VARIABLE_WRITE_ARCH_PROTOCOL. The authenticated
+      // variable perhaps is not initialized, just return here.
+      //
+      DEBUG ((
+        DEBUG_ERROR,
+        "Update AUTH variable before EFI_VARIABLE_WRITE_ARCH_PROTOCOL ready - %r\n",
+        EFI_NOT_AVAILABLE_YET
+        ));
+      return FALSE;
+    }
+  }
+
+  return TRUE;
+}
+
+/**
+  Check parameters associated with the variable to update.
+
+  @param[in] Variable           Pointer to current variable on storage.
+  @param[in] CacheVariable      Pointer to current variable in cache.
   @param[in] VariableName       Name of variable.
   @param[in] VendorGuid         Guid of variable.
   @param[in] Data               Variable data.
@@ -1667,9 +1999,130 @@ AutoUpdateLangVariable (
   @param[in] Attributes         Attributes of the variable.
   @param[in] KeyIndex           Index of associated public key.
   @param[in] MonotonicCount     Value of associated monotonic count.
-  @param[in, out] CacheVariable The variable information which is used to keep track of variable usage.
   @param[in] TimeStamp          Value of associated TimeStamp.
 
+  @retval EFI_SUCCESS           The variable is ok to be updated.
+  @retval EFI_ALREADY_STARTED   No need to update the variable.
+  @retval EFI_WRITE_PROTECTED   The variable cannot be updated.
+  @retval EFI_INVALID_PARAMETER The variable attributes are not valid.
+  @retval EFI_NOT_FOUND         Trying to delete non-existing variable.
+
+**/
+EFI_STATUS
+ValidateVariableParameters (
+  IN VARIABLE_POINTER_TRACK  *Variable,
+  IN VARIABLE_POINTER_TRACK  *CacheVariable,
+  IN CHAR16                  *VariableName,
+  IN EFI_GUID                *VendorGuid,
+  IN VOID                    *Data,
+  IN UINTN                   DataSize,
+  IN UINT32                  Attributes,
+  IN UINT32                  KeyIndex,
+  IN UINT64                  MonotonicCount,
+  IN EFI_TIME                *TimeStamp
+  )
+{
+  BOOLEAN  AuthFlag;
+
+  AuthFlag = mVariableModuleGlobal->VariableGlobal.AuthFormat;
+
+  if ((DataSize == 0) && ((Attributes & EFI_VARIABLE_APPEND_WRITE) != 0)) {
+    return EFI_ALREADY_STARTED;
+  }
+
+  if (Variable->CurrPtr != NULL) {
+    //
+    // Update/Delete existing variable.
+    //
+    if (AtRuntime ()) {
+      //
+      // If AtRuntime and the variable is Volatile and Runtime Access,
+      // the volatile is ReadOnly, and SetVariable should be aborted and
+      // return EFI_WRITE_PROTECTED.
+      //
+      if (Variable->Volatile) {
+        return EFI_WRITE_PROTECTED;
+      }
+
+      //
+      // Only variable that have NV attributes can be updated/deleted in Runtime.
+      //
+      if ((CacheVariable->CurrPtr->Attributes & EFI_VARIABLE_NON_VOLATILE) == 0) {
+        return EFI_INVALID_PARAMETER;
+      }
+
+      //
+      // Only variable that have RT attributes can be updated/deleted in Runtime.
+      //
+      if ((CacheVariable->CurrPtr->Attributes & EFI_VARIABLE_RUNTIME_ACCESS) == 0) {
+        return EFI_INVALID_PARAMETER;
+      }
+    }
+
+    //
+    // Variable content unchanged and no need to update timestamp, just return.
+    //
+    if (  ((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0)
+       && (TimeStamp == NULL)
+       && (DataSizeOfVariable (CacheVariable->CurrPtr, AuthFlag) == DataSize)
+       && (CompareMem (Data, GetVariableDataPtr (CacheVariable->CurrPtr, AuthFlag), DataSize) == 0))
+    {
+      UpdateVariableInfo (
+        VariableName,
+        VendorGuid,
+        Variable->Volatile,
+        FALSE,
+        TRUE,
+        FALSE,
+        FALSE,
+        &gVariableInfo
+        );
+      return EFI_ALREADY_STARTED;
+    }
+  } else {
+    //
+    // Create a new variable.
+    //
+
+    //
+    // Make sure we are trying to create a new variable. You cannot delete a new
+    // variable.
+    //
+    if ((DataSize == 0) ||
+        ((Attributes & (EFI_VARIABLE_RUNTIME_ACCESS|EFI_VARIABLE_BOOTSERVICE_ACCESS)) == 0))
+    {
+      return EFI_NOT_FOUND;
+    }
+
+    //
+    // Only variable have NV|RT attribute can be created in Runtime.
+    //
+    if (  AtRuntime ()
+       && (  ((Attributes & EFI_VARIABLE_RUNTIME_ACCESS) == 0)
+          || ((Attributes & EFI_VARIABLE_NON_VOLATILE) == 0)))
+    {
+      return EFI_INVALID_PARAMETER;
+    }
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Update the variable region with Variable information. If EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS is set,
+  index of associated public key is needed.
+
+  @param[in]      VariableName       Name of variable.
+  @param[in]      VendorGuid         Guid of variable.
+  @param[in]      Data               Variable data.
+  @param[in]      DataSize           Size of data. 0 means delete.
+  @param[in]      Attributes         Attributes of the variable.
+  @param[in]      KeyIndex           Index of associated public key.
+  @param[in]      MonotonicCount     Value of associated monotonic count.
+  @param[in,out]  CacheVariable      The variable information which is used
+                                     to keep track of variable usage.
+  @param[in]      TimeStamp          Value of associated TimeStamp.
+
   @retval EFI_SUCCESS           The update operation is success.
   @retval EFI_OUT_OF_RESOURCES  Variable region is full, can not write other data into this region.
 
@@ -1687,710 +2140,381 @@ UpdateVariable (
   IN      EFI_TIME                *TimeStamp      OPTIONAL
   )
 {
-  EFI_STATUS                          Status;
-  VARIABLE_HEADER                     *NextVariable;
-  UINTN                               ScratchSize;
-  UINTN                               MaxDataSize;
-  UINTN                               VarNameOffset;
-  UINTN                               VarDataOffset;
-  UINTN                               VarNameSize;
-  UINTN                               VarSize;
-  BOOLEAN                             Volatile;
-  EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *Fvb;
-  UINT8                               State;
-  VARIABLE_POINTER_TRACK              *Variable;
-  VARIABLE_POINTER_TRACK              NvVariable;
-  VARIABLE_STORE_HEADER               *VariableStoreHeader;
-  VARIABLE_RUNTIME_CACHE              *VolatileCacheInstance;
-  UINT8                               *BufferForMerge;
-  UINTN                               MergedBufSize;
-  BOOLEAN                             DataReady;
-  UINTN                               DataOffset;
-  BOOLEAN                             IsCommonVariable;
-  BOOLEAN                             IsCommonUserVariable;
-  AUTHENTICATED_VARIABLE_HEADER       *AuthVariable;
-  BOOLEAN                             AuthFormat;
+  EFI_STATUS              Status;
+  VARIABLE_GLOBAL         *VarGlobal;
+  VARIABLE_HEADER         *NewVariable;
+  VARIABLE_HEADER         *NextVariable;
+  VARIABLE_HEADER         *UpdatingVariable;
+  UINTN                   VarSize;
+  UINTN                   UpdateSize;
+  UINTN                   Offset;
+  VARIABLE_POINTER_TRACK  *Variable;
+  VARIABLE_POINTER_TRACK  NvVariable;
+  VARIABLE_STORE_HEADER   *VariableStoreHeader;
+  VARIABLE_RUNTIME_CACHE  *VolatileCacheInstance;
+  BOOLEAN                 IsCommonVariable;
+  BOOLEAN                 IsCommonUserVariable;
+  BOOLEAN                 DeleteFlag;
+  BOOLEAN                 VolatileFlag;
+  BOOLEAN                 HobVarOnlyFlag;
+  EFI_PHYSICAL_ADDRESS    VarStoreBase;
+  UINTN                   *LastVariableOffset;
 
-  if ((mVariableModuleGlobal->FvbInstance == NULL) && !mVariableModuleGlobal->VariableGlobal.EmuNvMode) {
-    //
-    // The FVB protocol is not ready, so the EFI_VARIABLE_WRITE_ARCH_PROTOCOL is not installed.
-    //
-    if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
-      //
-      // Trying to update NV variable prior to the installation of EFI_VARIABLE_WRITE_ARCH_PROTOCOL
-      //
-      DEBUG ((DEBUG_ERROR, "Update NV variable before EFI_VARIABLE_WRITE_ARCH_PROTOCOL ready - %r\n", EFI_NOT_AVAILABLE_YET));
-      return EFI_NOT_AVAILABLE_YET;
-    } else if ((Attributes & VARIABLE_ATTRIBUTE_AT_AW) != 0) {
-      //
-      // Trying to update volatile authenticated variable prior to the installation of EFI_VARIABLE_WRITE_ARCH_PROTOCOL
-      // The authenticated variable perhaps is not initialized, just return here.
-      //
-      DEBUG ((DEBUG_ERROR, "Update AUTH variable before EFI_VARIABLE_WRITE_ARCH_PROTOCOL ready - %r\n", EFI_NOT_AVAILABLE_YET));
-      return EFI_NOT_AVAILABLE_YET;
-    }
+  if (!ReadyForUpdate (Attributes)) {
+    return EFI_NOT_AVAILABLE_YET;
   }
 
-  AuthFormat = mVariableModuleGlobal->VariableGlobal.AuthFormat;
+  VarGlobal = &mVariableModuleGlobal->VariableGlobal;
+
+  if (  (((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0) && (DataSize == 0))
+     || (Attributes == 0)
+     || (AtRuntime () && ((Attributes & (EFI_VARIABLE_RUNTIME_ACCESS
+                                         |EFI_VARIABLE_BOOTSERVICE_ACCESS)) == 0)))
+  {
+    DeleteFlag = TRUE;
+  } else {
+    DeleteFlag = FALSE;
+  }
+
+  if (  ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0)
+     || ((CacheVariable->CurrPtr != NULL) &&
+         ((CacheVariable->CurrPtr->Attributes & EFI_VARIABLE_NON_VOLATILE) != 0)))
+  {
+    VolatileFlag = FALSE;
+  } else {
+    VolatileFlag = TRUE;
+  }
 
   //
   // Check if CacheVariable points to the variable in variable HOB.
   // If yes, let CacheVariable points to the variable in NV variable cache.
   //
-  if ((CacheVariable->CurrPtr != NULL) &&
-      (mVariableModuleGlobal->VariableGlobal.HobVariableBase != 0) &&
-      (CacheVariable->StartPtr == GetStartPointer ((VARIABLE_STORE_HEADER *)(UINTN)mVariableModuleGlobal->VariableGlobal.HobVariableBase))
-      )
-  {
-    CacheVariable->StartPtr = GetStartPointer (mNvVariableCache);
-    CacheVariable->EndPtr   = GetEndPointer (mNvVariableCache);
-    CacheVariable->Volatile = FALSE;
-    Status                  = FindVariableEx (VariableName, VendorGuid, FALSE, CacheVariable, AuthFormat);
+  HobVarOnlyFlag = FALSE;
+  if (IsHobVariable (CacheVariable)) {
+    Status = RebaseVariablePtr (
+               CacheVariable,
+               CacheVariable,
+               mNvVariableCache,
+               VariableName,
+               VendorGuid,
+               FALSE
+               );
     if ((CacheVariable->CurrPtr == NULL) || EFI_ERROR (Status)) {
       //
       // There is no matched variable in NV variable cache.
       //
-      if ((((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0) && (DataSize == 0)) || (Attributes == 0)) {
+      if (DeleteFlag) {
         //
-        // It is to delete variable,
-        // go to delete this variable in variable HOB and
-        // try to flush other variables from HOB to flash.
+        // Leave the deletion to FlushHobVariableToFlash() before return.
         //
-        UpdateVariableInfo (VariableName, VendorGuid, FALSE, FALSE, FALSE, TRUE, FALSE, &gVariableInfo);
-        FlushHobVariableToFlash (VariableName, VendorGuid);
-        return EFI_SUCCESS;
+        HobVarOnlyFlag = TRUE;
+        Status         = EFI_SUCCESS;
+        goto Done;
       }
     }
   }
 
+  //
+  // Determine the physical position of variable store to update, due to cache
+  // mechanims of variable service.
+  //
   if ((CacheVariable->CurrPtr == NULL) || CacheVariable->Volatile) {
+    //
+    // - Add new variable (volatile or non-volatile); Or
+    // - Update/delete volatile variable in place.
+    //
     Variable = CacheVariable;
   } else {
     //
-    // Update/Delete existing NV variable.
-    // CacheVariable points to the variable in the memory copy of Flash area
-    // Now let Variable points to the same variable in Flash area.
+    // - Update/Delete existing NV variable.
+    //    CacheVariable points to the variable in the memory copy of Flash area.
+    //    Now let Variable points to the same variable in Flash area.
     //
-    VariableStoreHeader = (VARIABLE_STORE_HEADER *)((UINTN)mVariableModuleGlobal->VariableGlobal.NonVolatileVariableBase);
-    Variable            = &NvVariable;
-    Variable->StartPtr  = GetStartPointer (VariableStoreHeader);
-    Variable->EndPtr    = (VARIABLE_HEADER *)((UINTN)Variable->StartPtr + ((UINTN)CacheVariable->EndPtr - (UINTN)CacheVariable->StartPtr));
-
-    Variable->CurrPtr = (VARIABLE_HEADER *)((UINTN)Variable->StartPtr + ((UINTN)CacheVariable->CurrPtr - (UINTN)CacheVariable->StartPtr));
-    if (CacheVariable->InDeletedTransitionPtr != NULL) {
-      Variable->InDeletedTransitionPtr = (VARIABLE_HEADER *)((UINTN)Variable->StartPtr + ((UINTN)CacheVariable->InDeletedTransitionPtr - (UINTN)CacheVariable->StartPtr));
-    } else {
-      Variable->InDeletedTransitionPtr = NULL;
-    }
-
-    Variable->Volatile = FALSE;
+    VariableStoreHeader = (VARIABLE_STORE_HEADER *)(UINTN)
+                          VarGlobal->NonVolatileVariableBase;
+    Variable = &NvVariable;
+    Status   = RebaseVariablePtr (
+                 CacheVariable,
+                 Variable,
+                 VariableStoreHeader,
+                 VariableName,
+                 VendorGuid,
+                 TRUE
+                 );
+    ASSERT_EFI_ERROR (Status);
   }
 
-  Fvb = mVariableModuleGlobal->FvbInstance;
-
   //
-  // Tricky part: Use scratch data area at the end of volatile variable store
-  // as a temporary storage.
+  // Validate variable parameters.
   //
-  NextVariable = GetEndPointer ((VARIABLE_STORE_HEADER *)((UINTN)mVariableModuleGlobal->VariableGlobal.VolatileVariableBase));
-  ScratchSize  = mVariableModuleGlobal->ScratchBufferSize;
-  SetMem (NextVariable, ScratchSize, 0xff);
-  DataReady = FALSE;
-
-  if (Variable->CurrPtr != NULL) {
-    //
-    // Update/Delete existing variable.
-    //
-    if (AtRuntime ()) {
-      //
-      // If AtRuntime and the variable is Volatile and Runtime Access,
-      // the volatile is ReadOnly, and SetVariable should be aborted and
-      // return EFI_WRITE_PROTECTED.
-      //
-      if (Variable->Volatile) {
-        Status = EFI_WRITE_PROTECTED;
-        goto Done;
-      }
-
-      //
-      // Only variable that have NV attributes can be updated/deleted in Runtime.
-      //
-      if ((CacheVariable->CurrPtr->Attributes & EFI_VARIABLE_NON_VOLATILE) == 0) {
-        Status = EFI_INVALID_PARAMETER;
-        goto Done;
-      }
-
-      //
-      // Only variable that have RT attributes can be updated/deleted in Runtime.
-      //
-      if ((CacheVariable->CurrPtr->Attributes & EFI_VARIABLE_RUNTIME_ACCESS) == 0) {
-        Status = EFI_INVALID_PARAMETER;
-        goto Done;
-      }
-    }
-
-    //
-    // Setting a data variable with no access, or zero DataSize attributes
-    // causes it to be deleted.
-    // When the EFI_VARIABLE_APPEND_WRITE attribute is set, DataSize of zero will
-    // not delete the variable.
-    //
-    if ((((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0) && (DataSize == 0)) || ((Attributes & (EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS)) == 0)) {
-      if (Variable->InDeletedTransitionPtr != NULL) {
-        //
-        // Both ADDED and IN_DELETED_TRANSITION variable are present,
-        // set IN_DELETED_TRANSITION one to DELETED state first.
-        //
-        ASSERT (CacheVariable->InDeletedTransitionPtr != NULL);
-        State  = CacheVariable->InDeletedTransitionPtr->State;
-        State &= VAR_DELETED;
-        Status = UpdateVariableStore (
-                   &mVariableModuleGlobal->VariableGlobal,
-                   Variable->Volatile,
-                   FALSE,
-                   Fvb,
-                   (UINTN)&Variable->InDeletedTransitionPtr->State,
-                   sizeof (UINT8),
-                   &State
-                   );
-        if (!EFI_ERROR (Status)) {
-          if (!Variable->Volatile) {
-            CacheVariable->InDeletedTransitionPtr->State = State;
-          }
-        } else {
-          goto Done;
-        }
-      }
-
-      State  = CacheVariable->CurrPtr->State;
-      State &= VAR_DELETED;
-
-      Status = UpdateVariableStore (
-                 &mVariableModuleGlobal->VariableGlobal,
-                 Variable->Volatile,
-                 FALSE,
-                 Fvb,
-                 (UINTN)&Variable->CurrPtr->State,
-                 sizeof (UINT8),
-                 &State
-                 );
-      if (!EFI_ERROR (Status)) {
-        UpdateVariableInfo (VariableName, VendorGuid, Variable->Volatile, FALSE, FALSE, TRUE, FALSE, &gVariableInfo);
-        if (!Variable->Volatile) {
-          CacheVariable->CurrPtr->State = State;
-          FlushHobVariableToFlash (VariableName, VendorGuid);
-        }
-      }
+  Status = ValidateVariableParameters (
+             Variable,
+             CacheVariable,
+             VariableName,
+             VendorGuid,
+             Data,
+             DataSize,
+             Attributes,
+             KeyIndex,
+             MonotonicCount,
+             TimeStamp
+             );
+  if (EFI_ERROR (Status)) {
+    goto Done;
+  }
 
-      goto Done;
-    }
+  //
+  // Add or update a variable. Allocate a buffer to hold it temporarily.
+  //
+  NewVariable = GetNewVariableBuffer ();
 
+  //
+  // Fill-up variable data first, if necessary.
+  //
+  IsCommonVariable     = FALSE;
+  IsCommonUserVariable = FALSE;
+  if (DeleteFlag) {
     //
-    // If the variable is marked valid, and the same data has been passed in,
-    // then return to the caller immediately.
+    // No need to fill up variable buffer when deleting a variable. But the
+    // buffer is still needed if variable protection is employed.
     //
-    if ((DataSizeOfVariable (CacheVariable->CurrPtr, AuthFormat) == DataSize) &&
-        (CompareMem (Data, GetVariableDataPtr (CacheVariable->CurrPtr, AuthFormat), DataSize) == 0) &&
-        ((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0) &&
-        (TimeStamp == NULL))
-    {
-      //
-      // Variable content unchanged and no need to update timestamp, just return.
-      //
-      UpdateVariableInfo (VariableName, VendorGuid, Variable->Volatile, FALSE, TRUE, FALSE, FALSE, &gVariableInfo);
-      Status = EFI_SUCCESS;
-      goto Done;
-    } else if ((CacheVariable->CurrPtr->State == VAR_ADDED) ||
-               (CacheVariable->CurrPtr->State == (VAR_ADDED & VAR_IN_DELETED_TRANSITION)))
-    {
-      //
-      // EFI_VARIABLE_APPEND_WRITE attribute only effects for existing variable.
-      //
-      if ((Attributes & EFI_VARIABLE_APPEND_WRITE) != 0) {
-        //
-        // NOTE: From 0 to DataOffset of NextVariable is reserved for Variable Header and Name.
-        // From DataOffset of NextVariable is to save the existing variable data.
-        //
-        DataOffset     = GetVariableDataOffset (CacheVariable->CurrPtr, AuthFormat);
-        BufferForMerge = (UINT8 *)((UINTN)NextVariable + DataOffset);
-        CopyMem (
-          BufferForMerge,
-          (UINT8 *)((UINTN)CacheVariable->CurrPtr + DataOffset),
-          DataSizeOfVariable (CacheVariable->CurrPtr, AuthFormat)
-          );
-
-        //
-        // Set Max Auth/Non-Volatile/Volatile Variable Data Size as default MaxDataSize.
-        //
-        if ((Attributes & VARIABLE_ATTRIBUTE_AT_AW) != 0) {
-          MaxDataSize = mVariableModuleGlobal->MaxAuthVariableSize - DataOffset;
-        } else if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
-          MaxDataSize = mVariableModuleGlobal->MaxVariableSize - DataOffset;
-        } else {
-          MaxDataSize = mVariableModuleGlobal->MaxVolatileVariableSize - DataOffset;
-        }
-
-        //
-        // Append the new data to the end of existing data.
-        // Max Harware error record variable data size is different from common/auth variable.
-        //
-        if ((Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) == EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
-          MaxDataSize = PcdGet32 (PcdMaxHardwareErrorVariableSize) - DataOffset;
-        }
-
-        if (DataSizeOfVariable (CacheVariable->CurrPtr, AuthFormat) + DataSize > MaxDataSize) {
-          //
-          // Existing data size + new data size exceed maximum variable size limitation.
-          //
-          Status = EFI_INVALID_PARAMETER;
-          goto Done;
-        }
-
-        CopyMem (
-          (UINT8 *)(
-                    (UINTN)BufferForMerge + DataSizeOfVariable (CacheVariable->CurrPtr, AuthFormat)
-                    ),
-          Data,
-          DataSize
-          );
-        MergedBufSize = DataSizeOfVariable (CacheVariable->CurrPtr, AuthFormat) +
-                        DataSize;
-
-        //
-        // BufferForMerge(from DataOffset of NextVariable) has included the merged existing and new data.
-        //
-        Data      = BufferForMerge;
-        DataSize  = MergedBufSize;
-        DataReady = TRUE;
-      }
-
-      //
-      // Mark the old variable as in delete transition.
-      //
-      State  = CacheVariable->CurrPtr->State;
-      State &= VAR_IN_DELETED_TRANSITION;
-
-      Status = UpdateVariableStore (
-                 &mVariableModuleGlobal->VariableGlobal,
-                 Variable->Volatile,
-                 FALSE,
-                 Fvb,
-                 (UINTN)&Variable->CurrPtr->State,
-                 sizeof (UINT8),
-                 &State
-                 );
-      if (EFI_ERROR (Status)) {
-        goto Done;
-      }
-
-      if (!Variable->Volatile) {
-        CacheVariable->CurrPtr->State = State;
-      }
-    }
+    VarSize = 0;
   } else {
-    //
-    // Not found existing variable. Create a new variable.
-    //
+    VarSize = SetVariableData (
+                NewVariable,
+                CacheVariable->CurrPtr,
+                VariableName,
+                VendorGuid,
+                Data,
+                DataSize,
+                Attributes,
+                KeyIndex,
+                MonotonicCount,
+                TimeStamp
+                );
 
-    if ((DataSize == 0) && ((Attributes & EFI_VARIABLE_APPEND_WRITE) != 0)) {
-      Status = EFI_SUCCESS;
-      goto Done;
-    }
-
-    //
-    // Make sure we are trying to create a new variable.
-    // Setting a data variable with zero DataSize or no access attributes means to delete it.
-    //
-    if ((DataSize == 0) || ((Attributes & (EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS)) == 0)) {
-      Status = EFI_NOT_FOUND;
-      goto Done;
-    }
-
-    //
-    // Only variable have NV|RT attribute can be created in Runtime.
-    //
-    if (AtRuntime () &&
-        (((Attributes & EFI_VARIABLE_RUNTIME_ACCESS) == 0) || ((Attributes & EFI_VARIABLE_NON_VOLATILE) == 0)))
-    {
-      Status = EFI_INVALID_PARAMETER;
-      goto Done;
-    }
-  }
-
-  //
-  // Function part - create a new variable and copy the data.
-  // Both update a variable and create a variable will come here.
-  //
-  NextVariable->StartId = VARIABLE_DATA;
-  //
-  // NextVariable->State = VAR_ADDED;
-  //
-  NextVariable->Reserved = 0;
-  if (mVariableModuleGlobal->VariableGlobal.AuthFormat) {
-    AuthVariable                 = (AUTHENTICATED_VARIABLE_HEADER *)NextVariable;
-    AuthVariable->PubKeyIndex    = KeyIndex;
-    AuthVariable->MonotonicCount = MonotonicCount;
-    ZeroMem (&AuthVariable->TimeStamp, sizeof (EFI_TIME));
-
-    if (((Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) != 0) &&
-        (TimeStamp != NULL))
-    {
-      if ((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0) {
-        CopyMem (&AuthVariable->TimeStamp, TimeStamp, sizeof (EFI_TIME));
-      } else {
-        //
-        // In the case when the EFI_VARIABLE_APPEND_WRITE attribute is set, only
-        // when the new TimeStamp value is later than the current timestamp associated
-        // with the variable, we need associate the new timestamp with the updated value.
-        //
-        if (Variable->CurrPtr != NULL) {
-          if (VariableCompareTimeStampInternal (&(((AUTHENTICATED_VARIABLE_HEADER *)CacheVariable->CurrPtr)->TimeStamp), TimeStamp)) {
-            CopyMem (&AuthVariable->TimeStamp, TimeStamp, sizeof (EFI_TIME));
-          } else {
-            CopyMem (&AuthVariable->TimeStamp, &(((AUTHENTICATED_VARIABLE_HEADER *)CacheVariable->CurrPtr)->TimeStamp), sizeof (EFI_TIME));
-          }
-        }
-      }
-    }
-  }
-
-  //
-  // The EFI_VARIABLE_APPEND_WRITE attribute will never be set in the returned
-  // Attributes bitmask parameter of a GetVariable() call.
-  //
-  NextVariable->Attributes = Attributes & (~EFI_VARIABLE_APPEND_WRITE);
-
-  VarNameOffset = GetVariableHeaderSize (AuthFormat);
-  VarNameSize   = StrSize (VariableName);
-  CopyMem (
-    (UINT8 *)((UINTN)NextVariable + VarNameOffset),
-    VariableName,
-    VarNameSize
-    );
-  VarDataOffset = VarNameOffset + VarNameSize + GET_PAD_SIZE (VarNameSize);
-
-  //
-  // If DataReady is TRUE, it means the variable data has been saved into
-  // NextVariable during EFI_VARIABLE_APPEND_WRITE operation preparation.
-  //
-  if (!DataReady) {
-    CopyMem (
-      (UINT8 *)((UINTN)NextVariable + VarDataOffset),
-      Data,
-      DataSize
-      );
-  }
-
-  CopyMem (
-    GetVendorGuidPtr (NextVariable, AuthFormat),
-    VendorGuid,
-    sizeof (EFI_GUID)
-    );
-  //
-  // There will be pad bytes after Data, the NextVariable->NameSize and
-  // NextVariable->DataSize should not include pad size so that variable
-  // service can get actual size in GetVariable.
-  //
-  SetNameSizeOfVariable (NextVariable, VarNameSize, AuthFormat);
-  SetDataSizeOfVariable (NextVariable, DataSize, AuthFormat);
-
-  //
-  // The actual size of the variable that stores in storage should
-  // include pad size.
-  //
-  VarSize = VarDataOffset + DataSize + GET_PAD_SIZE (DataSize);
-  if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
-    //
-    // Create a nonvolatile variable.
-    //
-    Volatile = FALSE;
-
-    IsCommonVariable     = FALSE;
-    IsCommonUserVariable = FALSE;
     if ((Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) == 0) {
       IsCommonVariable     = TRUE;
-      IsCommonUserVariable = IsUserVariable (NextVariable);
+      IsCommonUserVariable = IsUserVariable (NewVariable);
     }
+  }
 
-    if (  (  ((Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) != 0)
-          && ((VarSize + mVariableModuleGlobal->HwErrVariableTotalSize) > PcdGet32 (PcdHwErrStorageSize)))
-       || (IsCommonVariable && ((VarSize + mVariableModuleGlobal->CommonVariableTotalSize) > mVariableModuleGlobal->CommonVariableSpace))
-       || (IsCommonVariable && AtRuntime () && ((VarSize + mVariableModuleGlobal->CommonVariableTotalSize) > mVariableModuleGlobal->CommonRuntimeVariableSpace))
-       || (IsCommonUserVariable && ((VarSize + mVariableModuleGlobal->CommonUserVariableTotalSize) > mVariableModuleGlobal->CommonMaxUserVariableSpace)))
-    {
-      if (AtRuntime ()) {
-        if (IsCommonUserVariable && ((VarSize + mVariableModuleGlobal->CommonUserVariableTotalSize) > mVariableModuleGlobal->CommonMaxUserVariableSpace)) {
-          RecordVarErrorFlag (VAR_ERROR_FLAG_USER_ERROR, VariableName, VendorGuid, Attributes, VarSize);
-        }
-
-        if (IsCommonVariable && ((VarSize + mVariableModuleGlobal->CommonVariableTotalSize) > mVariableModuleGlobal->CommonRuntimeVariableSpace)) {
-          RecordVarErrorFlag (VAR_ERROR_FLAG_SYSTEM_ERROR, VariableName, VendorGuid, Attributes, VarSize);
-        }
-
-        Status = EFI_OUT_OF_RESOURCES;
-        goto Done;
-      }
-
-      //
-      // Perform garbage collection & reclaim operation, and integrate the new variable at the same time.
-      //
-      Status = Reclaim (
-                 mVariableModuleGlobal->VariableGlobal.NonVolatileVariableBase,
-                 &mVariableModuleGlobal->NonVolatileLastVariableOffset,
-                 FALSE,
-                 Variable,
-                 NextVariable,
-                 HEADER_ALIGN (VarSize)
-                 );
-      if (!EFI_ERROR (Status)) {
-        //
-        // The new variable has been integrated successfully during reclaiming.
-        //
-        if (Variable->CurrPtr != NULL) {
-          CacheVariable->CurrPtr                = (VARIABLE_HEADER *)((UINTN)CacheVariable->StartPtr + ((UINTN)Variable->CurrPtr - (UINTN)Variable->StartPtr));
-          CacheVariable->InDeletedTransitionPtr = NULL;
-        }
-
-        UpdateVariableInfo (VariableName, VendorGuid, FALSE, FALSE, TRUE, FALSE, FALSE, &gVariableInfo);
-        FlushHobVariableToFlash (VariableName, VendorGuid);
-      } else {
-        if (IsCommonUserVariable && ((VarSize + mVariableModuleGlobal->CommonUserVariableTotalSize) > mVariableModuleGlobal->CommonMaxUserVariableSpace)) {
-          RecordVarErrorFlag (VAR_ERROR_FLAG_USER_ERROR, VariableName, VendorGuid, Attributes, VarSize);
-        }
+  //
+  // We might need to do protection for non-volatile variable before flushing
+  // the data to storage. A null version (meaning no protection) of following
+  // APIs should simply return EFI_SUCCESS or EFI_UNSUPPORTED without any
+  // changes to original data.
+  //
+  if (!VolatileFlag) {
+    Status = ProtectedVariableLibUpdate (
+               Variable->CurrPtr,
+               Variable->InDeletedTransitionPtr,
+               NewVariable,
+               &VarSize
+               );
+    if (EFI_ERROR (Status) && (Status != EFI_UNSUPPORTED)) {
+      return Status;
+    }
 
-        if (IsCommonVariable && ((VarSize + mVariableModuleGlobal->CommonVariableTotalSize) > mVariableModuleGlobal->CommonVariableSpace)) {
-          RecordVarErrorFlag (VAR_ERROR_FLAG_SYSTEM_ERROR, VariableName, VendorGuid, Attributes, VarSize);
-        }
-      }
+    Status = EFI_SUCCESS;
+  }
 
+  //
+  // Mark the old variable as in delete transition first. There's no such need
+  // for deleting a variable, even if variable protection is employed.
+  //
+  if (  !DeleteFlag
+     && (CacheVariable->CurrPtr != NULL)
+     && (  (CacheVariable->CurrPtr->State == VAR_ADDED)
+        || (CacheVariable->CurrPtr->State == (VAR_ADDED & VAR_IN_DELETED_TRANSITION))))
+  {
+    Status = UpdateVariableState (
+               Variable->CurrPtr,
+               CacheVariable->CurrPtr,
+               CacheVariable->CurrPtr->State & VAR_IN_DELETED_TRANSITION,
+               Variable->Volatile
+               );
+    if (EFI_ERROR (Status)) {
       goto Done;
     }
-
-    if (!mVariableModuleGlobal->VariableGlobal.EmuNvMode) {
-      //
-      // Four steps
-      // 1. Write variable header
-      // 2. Set variable state to header valid
-      // 3. Write variable data
-      // 4. Set variable state to valid
-      //
-      //
-      // Step 1:
-      //
-      Status = UpdateVariableStore (
-                 &mVariableModuleGlobal->VariableGlobal,
-                 FALSE,
-                 TRUE,
-                 Fvb,
-                 mVariableModuleGlobal->NonVolatileLastVariableOffset,
-                 (UINT32)GetVariableHeaderSize (AuthFormat),
-                 (UINT8 *)NextVariable
-                 );
-
-      if (EFI_ERROR (Status)) {
-        goto Done;
-      }
-
-      //
-      // Step 2:
-      //
-      NextVariable->State = VAR_HEADER_VALID_ONLY;
-      Status              = UpdateVariableStore (
-                              &mVariableModuleGlobal->VariableGlobal,
-                              FALSE,
-                              TRUE,
-                              Fvb,
-                              mVariableModuleGlobal->NonVolatileLastVariableOffset + OFFSET_OF (VARIABLE_HEADER, State),
-                              sizeof (UINT8),
-                              &NextVariable->State
-                              );
-
-      if (EFI_ERROR (Status)) {
-        goto Done;
-      }
-
-      //
-      // Step 3:
-      //
-      Status = UpdateVariableStore (
-                 &mVariableModuleGlobal->VariableGlobal,
-                 FALSE,
-                 TRUE,
-                 Fvb,
-                 mVariableModuleGlobal->NonVolatileLastVariableOffset + GetVariableHeaderSize (AuthFormat),
-                 (UINT32)(VarSize - GetVariableHeaderSize (AuthFormat)),
-                 (UINT8 *)NextVariable + GetVariableHeaderSize (AuthFormat)
+  }
+
+  //
+  // Have enough space to store the variable?
+  //
+  Status = CheckVariableStoreSpace (
+             NewVariable,
+             VarSize,
+             VariableName,
+             VendorGuid,
+             Attributes,
+             VolatileFlag
+             );
+  if (Status == EFI_OUT_OF_RESOURCES) {
+    //
+    // Not a chance.
+    //
+    goto Done;
+  }
+
+  //
+  // Maybe not...
+  //
+  VarStoreBase = (VolatileFlag) ? VarGlobal->VolatileVariableBase
+                                : VarGlobal->NonVolatileVariableBase;
+  LastVariableOffset = (VolatileFlag)
+                        ? &mVariableModuleGlobal->VolatileLastVariableOffset
+                        : &mVariableModuleGlobal->NonVolatileLastVariableOffset;
+  if (!EFI_ERROR (Status)) {
+    //
+    // There's enough free space at the tail of variable storage.
+    //
+
+    //
+    // If non-volatile variable is protected, a separate variable (MetaDataHmacVar)
+    // is always updated along with current updating variable. The buffer pointed
+    // by NewVariable must have two variables. They should be written at this
+    // time orderly.
+    //
+    NextVariable     = NewVariable;
+    UpdatingVariable = NULL;
+    UpdateSize       = 0;
+    while (  !EFI_ERROR (Status)
+          && ((UINTN)NextVariable - (UINTN)NewVariable) < VarSize)
+    {
+      UpdatingVariable = NextVariable;
+      NextVariable     = GetNextVariablePtr (UpdatingVariable, VarGlobal->AuthFormat);
+      UpdateSize       = (UINTN)NextVariable - (UINTN)UpdatingVariable;
+
+      Status = WriteVariable (
+                 VarStoreBase,
+                 LastVariableOffset,
+                 &UpdatingVariable,
+                 (UINT32)UpdateSize,
+                 VolatileFlag,
+                 VarGlobal->AuthFormat
                  );
-
-      if (EFI_ERROR (Status)) {
-        goto Done;
-      }
-
-      //
-      // Step 4:
-      //
-      NextVariable->State = VAR_ADDED;
-      Status              = UpdateVariableStore (
-                              &mVariableModuleGlobal->VariableGlobal,
-                              FALSE,
-                              TRUE,
-                              Fvb,
-                              mVariableModuleGlobal->NonVolatileLastVariableOffset + OFFSET_OF (VARIABLE_HEADER, State),
-                              sizeof (UINT8),
-                              &NextVariable->State
-                              );
-
-      if (EFI_ERROR (Status)) {
-        goto Done;
-      }
-
-      //
-      // Update the memory copy of Flash region.
-      //
-      CopyMem ((UINT8 *)mNvVariableCache + mVariableModuleGlobal->NonVolatileLastVariableOffset, (UINT8 *)NextVariable, VarSize);
-    } else {
-      //
-      // Emulated non-volatile variable mode.
-      //
-      NextVariable->State = VAR_ADDED;
-      Status              = UpdateVariableStore (
-                              &mVariableModuleGlobal->VariableGlobal,
-                              FALSE,
-                              TRUE,
-                              Fvb,
-                              mVariableModuleGlobal->NonVolatileLastVariableOffset,
-                              (UINT32)VarSize,
-                              (UINT8 *)NextVariable
-                              );
-
-      if (EFI_ERROR (Status)) {
-        goto Done;
-      }
     }
 
-    mVariableModuleGlobal->NonVolatileLastVariableOffset += HEADER_ALIGN (VarSize);
-
+    //
+    // UpdatingVariable must point to the last written variable. Restore it to
+    // the first one so that we can calculate the offset in variable storage.
+    //
+    UpdatingVariable = (VARIABLE_HEADER *)((UINTN)UpdatingVariable + UpdateSize
+                                           - VarSize);
     if ((Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) != 0) {
-      mVariableModuleGlobal->HwErrVariableTotalSize += HEADER_ALIGN (VarSize);
+      mVariableModuleGlobal->HwErrVariableTotalSize += VarSize;
     } else {
-      mVariableModuleGlobal->CommonVariableTotalSize += HEADER_ALIGN (VarSize);
+      mVariableModuleGlobal->CommonVariableTotalSize += VarSize;
       if (IsCommonUserVariable) {
-        mVariableModuleGlobal->CommonUserVariableTotalSize += HEADER_ALIGN (VarSize);
+        mVariableModuleGlobal->CommonUserVariableTotalSize += VarSize;
       }
     }
-  } else {
-    //
-    // Create a volatile variable.
-    //
-    Volatile = TRUE;
 
-    if ((UINT32)(VarSize + mVariableModuleGlobal->VolatileLastVariableOffset) >
-        ((VARIABLE_STORE_HEADER *)((UINTN)(mVariableModuleGlobal->VariableGlobal.VolatileVariableBase)))->Size)
-    {
-      //
-      // Perform garbage collection & reclaim operation, and integrate the new variable at the same time.
-      //
-      Status = Reclaim (
-                 mVariableModuleGlobal->VariableGlobal.VolatileVariableBase,
-                 &mVariableModuleGlobal->VolatileLastVariableOffset,
-                 TRUE,
+    //
+    // Mark the old variable(s) as deleted.
+    //
+    if (!EFI_ERROR (Status) && (Variable->CurrPtr != NULL)) {
+      Status = DeleteVariable (
+                 VariableName,
+                 VendorGuid,
                  Variable,
-                 NextVariable,
-                 HEADER_ALIGN (VarSize)
+                 CacheVariable,
+                 VolatileFlag
                  );
-      if (!EFI_ERROR (Status)) {
-        //
-        // The new variable has been integrated successfully during reclaiming.
-        //
-        if (Variable->CurrPtr != NULL) {
-          CacheVariable->CurrPtr                = (VARIABLE_HEADER *)((UINTN)CacheVariable->StartPtr + ((UINTN)Variable->CurrPtr - (UINTN)Variable->StartPtr));
-          CacheVariable->InDeletedTransitionPtr = NULL;
-        }
-
-        UpdateVariableInfo (VariableName, VendorGuid, TRUE, FALSE, TRUE, FALSE, FALSE, &gVariableInfo);
-      }
-
-      goto Done;
     }
-
-    NextVariable->State = VAR_ADDED;
-    Status              = UpdateVariableStore (
-                            &mVariableModuleGlobal->VariableGlobal,
-                            TRUE,
-                            TRUE,
-                            Fvb,
-                            mVariableModuleGlobal->VolatileLastVariableOffset,
-                            (UINT32)VarSize,
-                            (UINT8 *)NextVariable
-                            );
-
-    if (EFI_ERROR (Status)) {
-      goto Done;
-    }
-
-    mVariableModuleGlobal->VolatileLastVariableOffset += HEADER_ALIGN (VarSize);
-  }
-
-  //
-  // Mark the old variable as deleted.
-  //
-  if (!EFI_ERROR (Status) && (Variable->CurrPtr != NULL)) {
-    if (Variable->InDeletedTransitionPtr != NULL) {
-      //
-      // Both ADDED and IN_DELETED_TRANSITION old variable are present,
-      // set IN_DELETED_TRANSITION one to DELETED state first.
-      //
-      ASSERT (CacheVariable->InDeletedTransitionPtr != NULL);
-      State  = CacheVariable->InDeletedTransitionPtr->State;
-      State &= VAR_DELETED;
-      Status = UpdateVariableStore (
-                 &mVariableModuleGlobal->VariableGlobal,
-                 Variable->Volatile,
-                 FALSE,
-                 Fvb,
-                 (UINTN)&Variable->InDeletedTransitionPtr->State,
-                 sizeof (UINT8),
-                 &State
-                 );
-      if (!EFI_ERROR (Status)) {
-        if (!Variable->Volatile) {
-          CacheVariable->InDeletedTransitionPtr->State = State;
-        }
-      } else {
-        goto Done;
-      }
-    }
-
-    State  = CacheVariable->CurrPtr->State;
-    State &= VAR_DELETED;
-
-    Status = UpdateVariableStore (
-               &mVariableModuleGlobal->VariableGlobal,
-               Variable->Volatile,
-               FALSE,
-               Fvb,
-               (UINTN)&Variable->CurrPtr->State,
-               sizeof (UINT8),
-               &State
+  } else {
+    //
+    // There's not enough space at the tail of variable storage but there's
+    // enough free space holes in the whole storage. Perform garbage collection
+    // & reclaim operation, and integrate the new variable at the same time.
+    //
+    Status = Reclaim (
+               VarStoreBase,
+               LastVariableOffset,
+               VolatileFlag,
+               Variable,
+               NewVariable,
+               VarSize
                );
-    if (!EFI_ERROR (Status) && !Variable->Volatile) {
-      CacheVariable->CurrPtr->State = State;
-    }
-  }
+    UpdatingVariable = Variable->CurrPtr;
 
-  if (!EFI_ERROR (Status)) {
-    UpdateVariableInfo (VariableName, VendorGuid, Volatile, FALSE, TRUE, FALSE, FALSE, &gVariableInfo);
-    if (!Volatile) {
-      FlushHobVariableToFlash (VariableName, VendorGuid);
+    if (EFI_ERROR (Status) &&
+        ((Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) == 0))
+    {
+      //
+      // Out of space.
+      //
+      IsCommonUserVariable = IsUserVariable (NewVariable);
+      IsCommonVariable     = TRUE;
+
+      if (IsCommonUserVariable &&
+          ((VarSize + mVariableModuleGlobal->CommonUserVariableTotalSize)
+           > mVariableModuleGlobal->CommonMaxUserVariableSpace))
+      {
+        RecordVarErrorFlag (
+          VAR_ERROR_FLAG_USER_ERROR,
+          VariableName,
+          VendorGuid,
+          Attributes,
+          VarSize
+          );
+      }
+
+      if (IsCommonVariable &&
+          ((VarSize + mVariableModuleGlobal->CommonVariableTotalSize)
+           > mVariableModuleGlobal->CommonVariableSpace))
+      {
+        RecordVarErrorFlag (
+          VAR_ERROR_FLAG_SYSTEM_ERROR,
+          VariableName,
+          VendorGuid,
+          Attributes,
+          VarSize
+          );
+      }
     }
   }
 
 Done:
   if (!EFI_ERROR (Status)) {
-    if (((Variable->CurrPtr != NULL) && !Variable->Volatile) || ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0)) {
-      VolatileCacheInstance = &(mVariableModuleGlobal->VariableGlobal.VariableRuntimeCacheContext.VariableRuntimeNvCache);
+    if (!VolatileFlag) {
+      Offset = (UpdatingVariable != NULL) ? (UINTN)UpdatingVariable - (UINTN)VarStoreBase
+                                          : 0;
+      Status = ProtectedVariableLibWriteFinal (
+                 NewVariable,
+                 VarSize,
+                 Offset
+                 );
+      if (EFI_ERROR (Status) && (Status != EFI_UNSUPPORTED)) {
+        return Status;
+      }
+
+      Status = EFI_SUCCESS;
+    }
+
+    UpdateVariableInfo (
+      VariableName,
+      VendorGuid,
+      VolatileFlag,
+      FALSE,
+      TRUE,
+      FALSE,
+      FALSE,
+      &gVariableInfo
+      );
+    //
+    // HOB copy of the same variable is no longer needed, no matter it has
+    // been deleted, updated or added from/to real variable storage.
+    //
+    if (HobVarOnlyFlag || !VolatileFlag) {
+      FlushHobVariableToFlash (VariableName, VendorGuid);
+    }
+
+    if (!VolatileFlag) {
+      VolatileCacheInstance = &(VarGlobal->VariableRuntimeCacheContext.VariableRuntimeNvCache);
     } else {
-      VolatileCacheInstance = &(mVariableModuleGlobal->VariableGlobal.VariableRuntimeCacheContext.VariableRuntimeVolatileCache);
+      VolatileCacheInstance = &(VarGlobal->VariableRuntimeCacheContext.VariableRuntimeVolatileCache);
     }
 
     if (VolatileCacheInstance->Store != NULL) {
@@ -2401,6 +2525,11 @@ Done:
                   );
       ASSERT_EFI_ERROR (Status);
     }
+  } else if (Status == EFI_ALREADY_STARTED) {
+    //
+    // Meaning nothing needs to be done. Just return success.
+    //
+    Status = EFI_SUCCESS;
   }
 
   return Status;
@@ -2440,7 +2569,6 @@ VariableServiceGetVariable (
 {
   EFI_STATUS              Status;
   VARIABLE_POINTER_TRACK  Variable;
-  UINTN                   VarDataSize;
 
   if ((VariableName == NULL) || (VendorGuid == NULL) || (DataSize == NULL)) {
     return EFI_INVALID_PARAMETER;
@@ -2458,28 +2586,26 @@ VariableServiceGetVariable (
   }
 
   //
-  // Get data size
+  // Get data and its size
   //
-  VarDataSize = DataSizeOfVariable (Variable.CurrPtr, mVariableModuleGlobal->VariableGlobal.AuthFormat);
-  ASSERT (VarDataSize != 0);
+  if (!Variable.Volatile) {
+    //
+    // Currently only non-volatile variable needs protection.
+    //
+    Status = ProtectedVariableLibGetByBuffer (
+               Variable.CurrPtr,
+               Data,
+               (UINT32 *)DataSize,
+               mVariableModuleGlobal->VariableGlobal.AuthFormat
+               );
+  }
 
-  if (*DataSize >= VarDataSize) {
-    if (Data == NULL) {
-      Status = EFI_INVALID_PARAMETER;
-      goto Done;
-    }
+  if (Variable.Volatile || (Status == EFI_UNSUPPORTED)) {
+    Status = GetVariableData (Variable.CurrPtr, Data, (UINT32 *)DataSize, mVariableModuleGlobal->VariableGlobal.AuthFormat);
+  }
 
-    CopyMem (Data, GetVariableDataPtr (Variable.CurrPtr, mVariableModuleGlobal->VariableGlobal.AuthFormat), VarDataSize);
-
-    *DataSize = VarDataSize;
+  if (!EFI_ERROR (Status)) {
     UpdateVariableInfo (VariableName, VendorGuid, Variable.Volatile, TRUE, FALSE, FALSE, FALSE, &gVariableInfo);
-
-    Status = EFI_SUCCESS;
-    goto Done;
-  } else {
-    *DataSize = VarDataSize;
-    Status    = EFI_BUFFER_TOO_SMALL;
-    goto Done;
   }
 
 Done:
@@ -2860,7 +2986,7 @@ VariableServiceSetVariable (
     // Parse non-volatile variable data and get last variable offset.
     //
     NextVariable = GetStartPointer ((VARIABLE_STORE_HEADER *)(UINTN)Point);
-    while (IsValidVariableHeader (NextVariable, GetEndPointer ((VARIABLE_STORE_HEADER *)(UINTN)Point))) {
+    while (IsValidVariableHeader (NextVariable, GetEndPointer ((VARIABLE_STORE_HEADER *)(UINTN)Point), AuthFormat)) {
       NextVariable = GetNextVariablePtr (NextVariable, AuthFormat);
     }
 
@@ -3022,7 +3148,12 @@ VariableServiceQueryVariableInfoInternal (
   //
   // Now walk through the related variable store.
   //
-  while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader))) {
+  while (IsValidVariableHeader (
+           Variable,
+           GetEndPointer (VariableStoreHeader),
+           mVariableModuleGlobal->VariableGlobal.AuthFormat
+           ))
+  {
     NextVariable = GetNextVariablePtr (Variable, mVariableModuleGlobal->VariableGlobal.AuthFormat);
     VariableSize = (UINT64)(UINTN)NextVariable - (UINT64)(UINTN)Variable;
 
@@ -3315,7 +3446,7 @@ FlushHobVariableToFlash (
     //
     mVariableModuleGlobal->VariableGlobal.HobVariableBase = 0;
     for ( Variable = GetStartPointer (VariableStoreHeader)
-          ; IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader))
+          ; IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader), AuthFormat)
           ; Variable = GetNextVariablePtr (Variable, AuthFormat)
           )
     {
@@ -3525,11 +3656,11 @@ ConvertNormalVarStorageToAuthVarStorage (
   VARIABLE_HEADER                *StartPtr;
   UINT8                          *NextPtr;
   VARIABLE_HEADER                *EndPtr;
-  UINTN                          AuthVarStroageSize;
+  UINTN                          AuthVarStorageSize;
   AUTHENTICATED_VARIABLE_HEADER  *AuthStartPtr;
   VARIABLE_STORE_HEADER          *AuthVarStorage;
 
-  AuthVarStroageSize = sizeof (VARIABLE_STORE_HEADER);
+  AuthVarStorageSize = sizeof (VARIABLE_STORE_HEADER);
   //
   // Set AuthFormat as FALSE for normal variable storage
   //
@@ -3542,10 +3673,10 @@ ConvertNormalVarStorageToAuthVarStorage (
   EndPtr   = GetEndPointer (NormalVarStorage);
   while (StartPtr < EndPtr) {
     if (StartPtr->State == VAR_ADDED) {
-      AuthVarStroageSize  = HEADER_ALIGN (AuthVarStroageSize);
-      AuthVarStroageSize += sizeof (AUTHENTICATED_VARIABLE_HEADER);
-      AuthVarStroageSize += StartPtr->NameSize + GET_PAD_SIZE (StartPtr->NameSize);
-      AuthVarStroageSize += StartPtr->DataSize + GET_PAD_SIZE (StartPtr->DataSize);
+      AuthVarStorageSize  = HEADER_ALIGN (AuthVarStorageSize);
+      AuthVarStorageSize += sizeof (AUTHENTICATED_VARIABLE_HEADER);
+      AuthVarStorageSize += StartPtr->NameSize + GET_PAD_SIZE (StartPtr->NameSize);
+      AuthVarStorageSize += StartPtr->DataSize + GET_PAD_SIZE (StartPtr->DataSize);
     }
 
     StartPtr = GetNextVariablePtr (StartPtr, mVariableModuleGlobal->VariableGlobal.AuthFormat);
@@ -3554,7 +3685,7 @@ ConvertNormalVarStorageToAuthVarStorage (
   //
   // Allocate Runtime memory for Auth Variable Storage
   //
-  AuthVarStorage = AllocateRuntimeZeroPool (AuthVarStroageSize);
+  AuthVarStorage = AllocateRuntimeZeroPool (AuthVarStorageSize);
   ASSERT (AuthVarStorage != NULL);
   if (AuthVarStorage == NULL) {
     return NULL;
@@ -3608,7 +3739,7 @@ ConvertNormalVarStorageToAuthVarStorage (
   AuthVarStorage->State  = NormalVarStorage->State;
   AuthVarStorage->Size   = (UINT32)((UINTN)AuthStartPtr - (UINTN)AuthVarStorage);
   CopyGuid (&AuthVarStorage->Signature, &gEfiAuthenticatedVariableGuid);
-  ASSERT (AuthVarStorage->Size <= AuthVarStroageSize);
+  ASSERT (AuthVarStorage->Size <= AuthVarStorageSize);
 
   //
   // Restore AuthFormat
@@ -3774,7 +3905,7 @@ VariableCommonInitialize (
   //
   // Allocate memory for volatile variable store, note that there is a scratch space to store scratch data.
   //
-  ScratchSize                              = GetMaxVariableSize ();
+  ScratchSize                              = GetMaxVariableSize () * 2;
   mVariableModuleGlobal->ScratchBufferSize = ScratchSize;
   VolatileVariableStore                    = AllocateRuntimePool (PcdGet32 (PcdVariableStoreSize) + ScratchSize);
   if (VolatileVariableStore == NULL) {
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableDxe.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableDxe.c
index 03fec3048dc4..52bf29ec4c5c 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableDxe.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableDxe.c
@@ -3,7 +3,7 @@
   and volatile storage space and install variable architecture protocol.
 
 Copyright (C) 2013, Red Hat, Inc.
-Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
 (C) Copyright 2015 Hewlett Packard Enterprise Development LP<BR>
 Copyright (c) Microsoft Corporation.
 SPDX-License-Identifier: BSD-2-Clause-Patent
@@ -14,6 +14,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 
 #include <Protocol/VariablePolicy.h>
 #include <Library/VariablePolicyLib.h>
+#include "VariableParsing.h"
 
 EFI_STATUS
 EFIAPI
@@ -534,6 +535,29 @@ VariableServiceInitialize (
   EFI_EVENT   ReadyToBootEvent;
   EFI_EVENT   EndOfDxeEvent;
 
+  PROTECTED_VARIABLE_CONTEXT_IN  ContextIn;
+
+  //
+  // Initialze protected variable service, if enabled.
+  //
+  ContextIn.StructSize    = sizeof (ContextIn);
+  ContextIn.StructVersion = PROTECTED_VARIABLE_CONTEXT_IN_STRUCT_VERSION;
+
+  ContextIn.FindVariableSmm     = NULL;
+  ContextIn.GetVariableInfo     = GetVariableInfo;
+  ContextIn.GetNextVariableInfo = GetNextVariableInfo;
+  ContextIn.UpdateVariableStore = VariableExLibUpdateNvVariable;
+  ContextIn.UpdateVariable      = VariableExLibUpdateVariable;
+
+  ContextIn.MaxVariableSize     = (UINT32)GetMaxVariableSize ();
+  ContextIn.VariableServiceUser = FromSmmModule;
+
+  Status = ProtectedVariableLibInitialize (&ContextIn);
+  if (EFI_ERROR (Status) && (Status != EFI_UNSUPPORTED)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
   Status = VariableCommonInitialize ();
   ASSERT_EFI_ERROR (Status);
 
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableExLib.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableExLib.c
index 62cde0335512..5904bcbff78a 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableExLib.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableExLib.c
@@ -1,13 +1,14 @@
 /** @file
   Provides variable driver extended services.
 
-Copyright (c) 2015 - 2019, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2015 - 2022, Intel Corporation. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
 #include "Variable.h"
 #include "VariableParsing.h"
+#include "VariableRuntimeCache.h"
 
 /**
   Finds variable in storage blocks of volatile and non-volatile storage areas.
@@ -38,6 +39,7 @@ VariableExLibFindVariable (
   EFI_STATUS                     Status;
   VARIABLE_POINTER_TRACK         Variable;
   AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
+  PROTECTED_VARIABLE_INFO        VarInfo;
 
   Status = FindVariable (
              VariableName,
@@ -56,9 +58,12 @@ VariableExLibFindVariable (
     return Status;
   }
 
-  AuthVariableInfo->DataSize   = DataSizeOfVariable (Variable.CurrPtr, mVariableModuleGlobal->VariableGlobal.AuthFormat);
-  AuthVariableInfo->Data       = GetVariableDataPtr (Variable.CurrPtr, mVariableModuleGlobal->VariableGlobal.AuthFormat);
-  AuthVariableInfo->Attributes = Variable.CurrPtr->Attributes;
+  AuthVariableInfo->NameSize     = NameSizeOfVariable (Variable.CurrPtr, mVariableModuleGlobal->VariableGlobal.AuthFormat);
+  AuthVariableInfo->VariableName = GetVariableNamePtr (Variable.CurrPtr, mVariableModuleGlobal->VariableGlobal.AuthFormat);
+  AuthVariableInfo->VendorGuid   = GetVendorGuidPtr (Variable.CurrPtr, mVariableModuleGlobal->VariableGlobal.AuthFormat);
+  AuthVariableInfo->DataSize     = DataSizeOfVariable (Variable.CurrPtr, mVariableModuleGlobal->VariableGlobal.AuthFormat);
+  AuthVariableInfo->Data         = GetVariableDataPtr (Variable.CurrPtr, mVariableModuleGlobal->VariableGlobal.AuthFormat);
+  AuthVariableInfo->Attributes   = Variable.CurrPtr->Attributes;
   if (mVariableModuleGlobal->VariableGlobal.AuthFormat) {
     AuthVariable                     = (AUTHENTICATED_VARIABLE_HEADER *)Variable.CurrPtr;
     AuthVariableInfo->PubKeyIndex    = AuthVariable->PubKeyIndex;
@@ -66,6 +71,24 @@ VariableExLibFindVariable (
     AuthVariableInfo->TimeStamp      = &AuthVariable->TimeStamp;
   }
 
+  CopyMem (&VarInfo.Header, AuthVariableInfo, sizeof (VarInfo.Header));
+
+  VarInfo.Buffer        = Variable.CurrPtr;
+  VarInfo.PlainData     = NULL;
+  VarInfo.PlainDataSize = 0;
+  VarInfo.Flags.Auth    = mVariableModuleGlobal->VariableGlobal.AuthFormat;
+
+  //
+  // In case the variable is encrypted.
+  //
+  Status = ProtectedVariableLibGetByInfo (&VarInfo);
+  if (!EFI_ERROR (Status)) {
+    if (VarInfo.PlainData != NULL) {
+      AuthVariableInfo->Data     = VarInfo.PlainData;
+      AuthVariableInfo->DataSize = VarInfo.PlainDataSize;
+    }
+  }
+
   return EFI_SUCCESS;
 }
 
@@ -99,6 +122,7 @@ VariableExLibFindNextVariable (
   VARIABLE_HEADER                *VariablePtr;
   AUTHENTICATED_VARIABLE_HEADER  *AuthVariablePtr;
   VARIABLE_STORE_HEADER          *VariableStoreHeader[VariableStoreTypeMax];
+  PROTECTED_VARIABLE_INFO        VarInfo;
 
   VariableStoreHeader[VariableStoreTypeVolatile] = (VARIABLE_STORE_HEADER *)(UINTN)mVariableModuleGlobal->VariableGlobal.VolatileVariableBase;
   VariableStoreHeader[VariableStoreTypeHob]      = (VARIABLE_STORE_HEADER *)(UINTN)mVariableModuleGlobal->VariableGlobal.HobVariableBase;
@@ -123,6 +147,7 @@ VariableExLibFindNextVariable (
     return Status;
   }
 
+  AuthVariableInfo->NameSize     = NameSizeOfVariable (VariablePtr, mVariableModuleGlobal->VariableGlobal.AuthFormat);
   AuthVariableInfo->VariableName = GetVariableNamePtr (VariablePtr, mVariableModuleGlobal->VariableGlobal.AuthFormat);
   AuthVariableInfo->VendorGuid   = GetVendorGuidPtr (VariablePtr, mVariableModuleGlobal->VariableGlobal.AuthFormat);
   AuthVariableInfo->DataSize     = DataSizeOfVariable (VariablePtr, mVariableModuleGlobal->VariableGlobal.AuthFormat);
@@ -135,6 +160,20 @@ VariableExLibFindNextVariable (
     AuthVariableInfo->TimeStamp      = &AuthVariablePtr->TimeStamp;
   }
 
+  CopyMem (&VarInfo.Header, AuthVariableInfo, sizeof (VarInfo.Header));
+
+  VarInfo.Buffer        = VariablePtr;
+  VarInfo.PlainData     = NULL;
+  VarInfo.PlainDataSize = 0;
+
+  Status = ProtectedVariableLibGetByInfo (&VarInfo);
+  if (!EFI_ERROR (Status)) {
+    if (VarInfo.PlainData != NULL) {
+      AuthVariableInfo->Data     = VarInfo.PlainData;
+      AuthVariableInfo->DataSize = VarInfo.PlainDataSize;
+    }
+  }
+
   return EFI_SUCCESS;
 }
 
@@ -256,3 +295,123 @@ VariableExLibAtRuntime (
 {
   return AtRuntime ();
 }
+
+/**
+  Update partial data of a variable on NV storage and/or cached copy.
+
+  @param[in]  VariableInfo  Pointer to a variable with detailed information.
+  @param[in]  Offset        Offset to write from.
+  @param[in]  Size          Size of data Buffer to update.
+  @param[in]  Buffer        Pointer to data buffer to update.
+
+  @retval EFI_SUCCESS             The variable data was updated successfully.
+  @retval EFI_UNSUPPORTED         If this function is called directly in runtime.
+  @retval EFI_INVALID_PARAMETER   If VariableInfo, Buffer or Size are not valid.
+  @retval Others                  Failed to update NV storage or variable cache.
+
+**/
+EFI_STATUS
+EFIAPI
+VariableExLibUpdateNvVariable (
+  IN  PROTECTED_VARIABLE_INFO  *VariableInfo,
+  IN  UINTN                    Offset,
+  IN  UINT32                   Size,
+  IN  UINT8                    *Buffer
+  )
+{
+  EFI_STATUS              Status;
+  VARIABLE_GLOBAL         *Global;
+  VARIABLE_RUNTIME_CACHE  *CacheInstance;
+  VARIABLE_HEADER         *VariableCache;
+
+  if ((mVariableModuleGlobal == NULL) || (mNvVariableCache == NULL)) {
+    return EFI_UNSUPPORTED;
+  }
+
+  //
+  // Flush the cache to store.
+  //
+  if (Size == (UINT32)-1) {
+    Status = FtwVariableSpace (
+               mVariableModuleGlobal->VariableGlobal.NonVolatileVariableBase,
+               mNvVariableCache
+               );
+    if (  !EFI_ERROR (Status)
+       && (mVariableModuleGlobal->VariableGlobal.HobVariableBase != 0))
+    {
+      FlushHobVariableToFlash (NULL, NULL);
+      if (mVariableModuleGlobal->VariableGlobal.HobVariableBase != 0) {
+        FreePool ((VOID *)(UINTN)mVariableModuleGlobal->VariableGlobal.HobVariableBase);
+        mVariableModuleGlobal->VariableGlobal.HobVariableBase = 0;
+      }
+    }
+
+    return Status;
+  }
+
+  if (  (VariableInfo == NULL)
+     || (VariableInfo->StoreIndex == VAR_INDEX_INVALID)
+     || (Buffer == NULL)
+     || (Size == 0))
+  {
+    ASSERT (VariableInfo != NULL);
+    ASSERT (VariableInfo->StoreIndex != VAR_INDEX_INVALID);
+    ASSERT (Buffer != NULL);
+    ASSERT (Size != 0);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Global = &mVariableModuleGlobal->VariableGlobal;
+
+  VariableCache = (VARIABLE_HEADER *)((UINTN)mNvVariableCache + (UINTN)VariableInfo->StoreIndex);
+
+  ASSERT (
+    StrCmp (
+      VariableInfo->Header.VariableName,
+      GetVariableNamePtr (VariableCache, Global->AuthFormat)
+      ) == 0
+    );
+  ASSERT (
+    CompareGuid (
+      VariableInfo->Header.VendorGuid,
+      GetVendorGuidPtr (VariableCache, Global->AuthFormat)
+      )
+    );
+
+  //
+  // Forcibly update part data of flash copy of the variable ...
+  //
+  Status =  UpdateVariableStore (
+              Global,
+              FALSE,
+              FALSE,
+              mVariableModuleGlobal->FvbInstance,
+              (UINTN)(Global->NonVolatileVariableBase + VariableInfo->StoreIndex + Offset),
+              Size,
+              Buffer
+              );
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
+  //
+  // ... as well as the local cached copy.
+  //
+  CopyMem ((VOID *)((UINTN)VariableCache + Offset), Buffer, Size);
+
+  //
+  // Sync remote cached copy.
+  //
+  CacheInstance = &Global->VariableRuntimeCacheContext.VariableRuntimeNvCache;
+  if (CacheInstance->Store != NULL) {
+    Status =  SynchronizeRuntimeVariableCache (
+                CacheInstance,
+                (UINTN)VariableInfo->StoreIndex + Offset,
+                Size
+                );
+    ASSERT_EFI_ERROR (Status);
+  }
+
+  return EFI_SUCCESS;
+}
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableNonVolatile.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableNonVolatile.c
index 5e9d40b67ac2..e8b8f0b7f705 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableNonVolatile.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableNonVolatile.c
@@ -1,7 +1,7 @@
 /** @file
   Common variable non-volatile store routines.
 
-Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2019 - 2022, Intel Corporation. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
@@ -120,6 +120,181 @@ InitEmuNonVolatileVariableStore (
   return EFI_SUCCESS;
 }
 
+/**
+
+  Create a dummy variable used to fill the gap in NV variable storage caused by
+  the invalid variables found in HMAC verification phase.
+
+  @param[out] Variable    Variable buffer.
+  @param[in]  Name        Variable Name.
+  @param[in]  Guid        Vendor GUID of the variable.
+  @param[in]  Size        Whole size of the variable requested.
+  @param[in]  AuthFlag    Variable format flag.
+
+**/
+STATIC
+VOID
+CreateDummyVariable (
+  OUT VARIABLE_HEADER  *Variable,
+  IN  CHAR16           *Name,
+  IN  EFI_GUID         *Guid,
+  IN  UINT32           Size,
+  IN  BOOLEAN          AuthFlag
+  )
+{
+  AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
+
+  ASSERT (Variable != NULL);
+
+  if (Name == NULL) {
+    Name = L"Dummy";
+  }
+
+  if (AuthFlag) {
+    AuthVariable = (AUTHENTICATED_VARIABLE_HEADER *)Variable;
+
+    AuthVariable->StartId    = VARIABLE_DATA;
+    AuthVariable->State      = VAR_ADDED & VAR_DELETED;
+    AuthVariable->Attributes = EFI_VARIABLE_NON_VOLATILE;
+    AuthVariable->NameSize   = (UINT32)StrSize (Name);
+    AuthVariable->DataSize   = Size - sizeof (AUTHENTICATED_VARIABLE_HEADER)
+                               - AuthVariable->NameSize;
+    if (Guid != NULL) {
+      CopyMem ((VOID *)&AuthVariable->VendorGuid, (VOID *)Guid, sizeof (EFI_GUID));
+    }
+
+    CopyMem (GetVariableNamePtr (Variable, AuthFlag), (VOID *)Name, AuthVariable->NameSize);
+  } else {
+    Variable->StartId    = VARIABLE_DATA;
+    Variable->State      = VAR_ADDED & VAR_DELETED;
+    Variable->Attributes = EFI_VARIABLE_NON_VOLATILE;
+    Variable->NameSize   = (UINT32)StrSize (Name);
+    Variable->DataSize   = Size - sizeof (VARIABLE_HEADER) - Variable->NameSize;
+    if (Guid != NULL) {
+      CopyMem ((VOID *)&Variable->VendorGuid, (VOID *)Guid, sizeof (EFI_GUID));
+    }
+
+    CopyMem (GetVariableNamePtr (Variable, AuthFlag), (VOID *)Name, Variable->NameSize);
+  }
+}
+
+/**
+
+  Init protected variable store.
+
+  @param[in, out]  VariableStore  Pointer to real protected variable store base.
+
+**/
+EFI_STATUS
+InitProtectedVariableStore (
+  IN  OUT VARIABLE_STORE_HEADER  *VariableStore
+  )
+{
+  EFI_STATUS               Status;
+  PROTECTED_VARIABLE_INFO  VarInfo;
+  UINTN                    Size;
+  UINTN                    Index;
+  BOOLEAN                  AuthFlag;
+  EFI_PHYSICAL_ADDRESS     NextVariableStore;
+  EFI_PHYSICAL_ADDRESS     *VarList;
+  UINTN                    NumVars;
+  UINTN                    CurrVar;
+
+  SetMem (
+    (UINT8 *)VariableStore + sizeof (VARIABLE_STORE_HEADER),
+    VariableStore->Size - sizeof (VARIABLE_STORE_HEADER),
+    0xFF
+    );
+  Index = sizeof (VARIABLE_STORE_HEADER);
+
+  VarList = NULL;
+  NumVars = 0;
+  ProtectedVariableLibGetSortedList (&VarList, &NumVars);
+
+  //
+  // Search variable in the order of StoreIndex
+  //
+  ZeroMem (&VarInfo, sizeof (VarInfo));
+
+  for (CurrVar = 0; CurrVar < NumVars; CurrVar++) {
+    VarInfo.Buffer     = NULL;
+    VarInfo.StoreIndex = VarList[CurrVar];
+    if (VarInfo.StoreIndex == VAR_INDEX_INVALID) {
+      break;
+    }
+
+    Status = ProtectedVariableLibFind (&VarInfo);
+    if (EFI_ERROR (Status)) {
+      break;
+    }
+
+    ASSERT (VarInfo.Buffer != NULL);
+
+    AuthFlag = VarInfo.Flags.Auth;
+    if (VarInfo.StoreIndex == VAR_INDEX_INVALID) {
+      continue;
+    } else {
+      ASSERT (VarInfo.StoreIndex == HEADER_ALIGN (VarInfo.StoreIndex));
+      ASSERT (VarInfo.StoreIndex < (VariableStore->Size - sizeof (VARIABLE_STORE_HEADER)));
+      ASSERT ((VariableStore->Size - VarInfo.StoreIndex) > GetVariableHeaderSize (AuthFlag));
+    }
+
+    //
+    // Fill gap caused by invalid variable.
+    //
+    if (VarInfo.StoreIndex > Index) {
+      Size = (UINTN)VarInfo.StoreIndex - Index;
+      CreateDummyVariable (
+        (VARIABLE_HEADER *)((UINT8 *)VariableStore + Index),
+        NULL,
+        NULL,
+        (UINT32)Size,
+        AuthFlag
+        );
+      Index += Size;
+    }
+
+    Size = (UINTN)GetNextVariablePtr (VarInfo.Buffer, AuthFlag)
+           - (UINTN)VarInfo.Buffer;
+    CopyMem ((UINT8 *)VariableStore + VarInfo.StoreIndex, VarInfo.Buffer, Size);
+
+    Index += Size;
+    Index  = HEADER_ALIGN (Index);
+
+    NextVariableStore = (EFI_PHYSICAL_ADDRESS)((UINTN)VariableStore + VarInfo.StoreIndex + Size);
+  }
+
+  //
+  // Search variable in the order of StoreIndex
+  //
+  ZeroMem (&VarInfo, sizeof (VarInfo));
+  for ( ; CurrVar < NumVars; CurrVar++) {
+    VarInfo.Buffer     = NULL;
+    VarInfo.StoreIndex = VarList[CurrVar];
+    Status             = ProtectedVariableLibFind (&VarInfo);
+    if (EFI_ERROR (Status)) {
+      break;
+    }
+
+    ASSERT (VarInfo.Buffer != NULL);
+
+    AuthFlag = VarInfo.Flags.Auth;
+    if (VarInfo.StoreIndex == VAR_INDEX_INVALID) {
+      Size = (UINTN)GetNextVariablePtr (VarInfo.Buffer, AuthFlag)
+             - (UINTN)VarInfo.Buffer;
+      CopyMem ((UINT8 *)&NextVariableStore, VarInfo.Buffer, Size);
+      Status            = ProtectedVariableLibRefresh (VarInfo.Buffer, 0, NextVariableStore - (UINTN)VariableStore, FALSE);
+      NextVariableStore = NextVariableStore + Size;
+    }
+  }
+
+  if (Status == EFI_UNSUPPORTED) {
+    return Status;
+  }
+
+  return EFI_SUCCESS;
+}
+
 /**
   Init real non-volatile variable store.
 
@@ -230,6 +405,16 @@ InitRealNonVolatileVariableStore (
     return EFI_VOLUME_CORRUPTED;
   }
 
+  //
+  // Overwrite the store with verified copy of protected variables, if enabled.
+  //
+  Status = InitProtectedVariableStore (VariableStore);
+  if ((Status != EFI_SUCCESS) && (Status != EFI_UNSUPPORTED)) {
+    FreePool (NvStorageData);
+    DEBUG ((DEBUG_ERROR, "Variable integrity might have been compromised\n"));
+    return Status;
+  }
+
   mNvFvHeaderCache = FvHeader;
 
   *VariableStoreBase = (EFI_PHYSICAL_ADDRESS)(UINTN)VariableStore;
@@ -323,7 +508,12 @@ InitNonVolatileVariableStore (
   // Parse non-volatile variable data and get last variable offset.
   //
   Variable = GetStartPointer (mNvVariableCache);
-  while (IsValidVariableHeader (Variable, GetEndPointer (mNvVariableCache))) {
+  while (IsValidVariableHeader (
+           Variable,
+           GetEndPointer (mNvVariableCache),
+           mVariableModuleGlobal->VariableGlobal.AuthFormat
+           ))
+  {
     NextVariable = GetNextVariablePtr (Variable, mVariableModuleGlobal->VariableGlobal.AuthFormat);
     VariableSize = (UINTN)NextVariable - (UINTN)Variable;
     if ((Variable->Attributes & (EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_HARDWARE_ERROR_RECORD)) == (EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_HARDWARE_ERROR_RECORD)) {
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.c
index 39060ed405b8..000e4b546888 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.c
@@ -2,11 +2,12 @@
   Functions in this module are associated with variable parsing operations and
   are intended to be usable across variable driver source files.
 
-Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2019 - 2022, Intel Corporation. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
+#include "Variable.h"
 #include "VariableParsing.h"
 
 /**
@@ -15,6 +16,8 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 
   @param[in] Variable           Pointer to the Variable Header.
   @param[in] VariableStoreEnd   Pointer to the Variable Store End.
+  @param[in] AuthFormat         TRUE indicates authenticated variables are used.
+                                FALSE indicates authenticated variables are not used.
 
   @retval TRUE              Variable header is valid.
   @retval FALSE             Variable header is not valid.
@@ -23,10 +26,14 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 BOOLEAN
 IsValidVariableHeader (
   IN  VARIABLE_HEADER  *Variable,
-  IN  VARIABLE_HEADER  *VariableStoreEnd
+  IN  VARIABLE_HEADER  *VariableStoreEnd,
+  IN  BOOLEAN          AuthFormat
   )
 {
-  if ((Variable == NULL) || (Variable >= VariableStoreEnd) || (Variable->StartId != VARIABLE_DATA)) {
+  if (  (Variable == NULL)
+     || (((UINTN)Variable + GetVariableHeaderSize (AuthFormat)) >= (UINTN)VariableStoreEnd)
+     || (Variable->StartId != VARIABLE_DATA))
+  {
     //
     // Variable is NULL or has reached the end of variable store,
     // or the StartId is not correct.
@@ -341,6 +348,52 @@ GetVariableDataOffset (
   return Value;
 }
 
+/**
+  Get variable data payload.
+
+  @param[in]      Variable     Pointer to the Variable Header.
+  @param[in,out]  Data         Pointer to buffer used to store the variable data.
+  @param[in,out]  DataSize     Size of buffer passed by Data.
+                               Size of data copied into Data buffer.
+  @param[in]      AuthFlag     Auth-variable indicator.
+
+  @return EFI_SUCCESS             Data was fetched.
+  @return EFI_INVALID_PARAMETER   DataSize is NULL.
+  @return EFI_BUFFER_TOO_SMALL    DataSize is smaller than size of variable data.
+
+**/
+EFI_STATUS
+GetVariableData (
+  IN      VARIABLE_HEADER  *Variable,
+  IN  OUT VOID             *Data,
+  IN  OUT UINT32           *DataSize,
+  IN      BOOLEAN          AuthFlag
+  )
+{
+  UINT32  Size;
+
+  if (DataSize == NULL) {
+    ASSERT (DataSize != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Size = (UINT32)DataSizeOfVariable (Variable, AuthFlag);
+  if (*DataSize < Size) {
+    *DataSize = Size;
+    return EFI_BUFFER_TOO_SMALL;
+  }
+
+  if (Data == NULL) {
+    ASSERT (Data != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  CopyMem (Data, GetVariableDataPtr (Variable, AuthFlag), Size);
+  *DataSize = Size;
+
+  return EFI_SUCCESS;
+}
+
 /**
 
   This code gets the pointer to the next variable header.
@@ -479,7 +532,7 @@ FindVariableEx (
   InDeletedVariable = NULL;
 
   for ( PtrTrack->CurrPtr = PtrTrack->StartPtr
-        ; IsValidVariableHeader (PtrTrack->CurrPtr, PtrTrack->EndPtr)
+        ; IsValidVariableHeader (PtrTrack->CurrPtr, PtrTrack->EndPtr, AuthFormat)
         ; PtrTrack->CurrPtr = GetNextVariablePtr (PtrTrack->CurrPtr, AuthFormat)
         )
   {
@@ -608,7 +661,7 @@ VariableServiceGetNextVariableInternal (
     //
     // Switch to the next variable store if needed
     //
-    while (!IsValidVariableHeader (Variable.CurrPtr, Variable.EndPtr)) {
+    while (!IsValidVariableHeader (Variable.CurrPtr, Variable.EndPtr, AuthFormat)) {
       //
       // Find current storage index
       //
@@ -804,3 +857,260 @@ UpdateVariableInfo (
     }
   }
 }
+
+/**
+
+  Retrieve details about a variable and return them in VariableInfo->Header.
+
+  If VariableInfo->Address is given, this function will calculate its offset
+  relative to given variable storage via VariableStore; Otherwise, it will try
+  other internal variable storages or cached copies. It's assumed that, for all
+  copies of NV variable storage, all variables are stored in the same relative
+  position. If VariableInfo->Address is found in the range of any storage copies,
+  its offset relative to that storage should be the same in other copies.
+
+  If VariableInfo->Offset is given (non-zero) but not VariableInfo->Address,
+  this function will return the variable memory address inside VariableStore,
+  if given, via VariableInfo->Address; Otherwise, the address of other storage
+  copies will be returned, if any.
+
+  For a new variable whose offset has not been determined, a value of -1 as
+  VariableInfo->Offset should be passed to skip the offset calculation.
+
+  @param[in,out] VariableInfo             Pointer to variable information.
+
+  @retval EFI_INVALID_PARAMETER  VariableInfo is NULL or both VariableInfo->Address
+                                 and VariableInfo->Offset are NULL (0).
+  @retval EFI_NOT_FOUND          If given Address or Offset is out of range of
+                                 any given or internal storage copies.
+  @retval EFI_SUCCESS            Variable details are retrieved successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+GetVariableInfo (
+  IN OUT  PROTECTED_VARIABLE_INFO  *VariableInfo
+  )
+{
+  VARIABLE_STORE_HEADER          *Stores[2];
+  UINTN                          Index;
+  VARIABLE_HEADER                *VariablePtr;
+  VARIABLE_HEADER                *VariableBuffer;
+  AUTHENTICATED_VARIABLE_HEADER  *AuthVariablePtr;
+  BOOLEAN                        AuthFlag;
+  UINTN                          NameSize;
+  UINTN                          DataSize;
+  UINTN                          VariableSize;
+
+  if ((VariableInfo == NULL) || (  (VariableInfo->Buffer == NULL)
+                                && (VariableInfo->StoreIndex == VAR_INDEX_INVALID)))
+  {
+    ASSERT (VariableInfo != NULL);
+    ASSERT (VariableInfo->Buffer != NULL || VariableInfo->StoreIndex != VAR_INDEX_INVALID);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Stores[0] = mNvVariableCache;
+  Stores[1] = (mVariableModuleGlobal != NULL)
+              ? (VARIABLE_STORE_HEADER *)(UINTN)mVariableModuleGlobal->VariableGlobal.NonVolatileVariableBase
+              : NULL;
+
+  VariableBuffer = VariableInfo->Buffer;
+  VariablePtr    = NULL;
+  if (VariableInfo->StoreIndex != VAR_INDEX_INVALID) {
+    for (Index = 0; Index < ARRAY_SIZE (Stores); ++Index) {
+      if (Stores[Index] == NULL) {
+        continue;
+      }
+
+      if ((UINTN)VariableInfo->StoreIndex
+          < ((UINTN)GetEndPointer (Stores[Index]) - (UINTN)Stores[Index]))
+      {
+        VariablePtr          = (VARIABLE_HEADER *)((UINTN)Stores[Index] + (UINTN)VariableInfo->StoreIndex);
+        VariableInfo->Buffer = VariablePtr;
+        break;
+      }
+    }
+  } else {
+    VariablePtr = VariableInfo->Buffer;
+  }
+
+  if (VariablePtr == NULL) {
+    return EFI_NOT_FOUND;
+  }
+
+  AuthFlag = VariableInfo->Flags.Auth;
+  ASSERT (AuthFlag == TRUE || AuthFlag == FALSE);
+
+  //
+  // Make a copy of the whole variable if a buffer is passed in.
+  //
+  if ((VariableBuffer != NULL) && (VariableBuffer != VariablePtr)) {
+    VariableSize = (UINTN)GetNextVariablePtr (VariablePtr, AuthFlag)
+                   - (UINTN)VariablePtr;
+    CopyMem (VariableBuffer, VariablePtr, VariableSize);
+  }
+
+  //
+  // AuthVariable header
+  //
+  if (AuthFlag) {
+    AuthVariablePtr = (AUTHENTICATED_VARIABLE_HEADER *)VariablePtr;
+
+    VariableInfo->Header.State          = AuthVariablePtr->State;
+    VariableInfo->Header.Attributes     = AuthVariablePtr->Attributes;
+    VariableInfo->Header.PubKeyIndex    = AuthVariablePtr->PubKeyIndex;
+    VariableInfo->Header.MonotonicCount = ReadUnaligned64 (
+                                            &(AuthVariablePtr->MonotonicCount)
+                                            );
+    if (VariableInfo->Header.TimeStamp != NULL) {
+      CopyMem (
+        VariableInfo->Header.TimeStamp,
+        &AuthVariablePtr->TimeStamp,
+        sizeof (EFI_TIME)
+        );
+    } else if (VariableBuffer != NULL) {
+      AuthVariablePtr                = (AUTHENTICATED_VARIABLE_HEADER *)VariableBuffer;
+      VariableInfo->Header.TimeStamp = &AuthVariablePtr->TimeStamp;
+    }
+  } else {
+    VariableInfo->Header.State          = VariablePtr->State;
+    VariableInfo->Header.Attributes     = VariablePtr->Attributes;
+    VariableInfo->Header.PubKeyIndex    = 0;
+    VariableInfo->Header.MonotonicCount = 0;
+    VariableInfo->Header.TimeStamp      = NULL;
+  }
+
+  //
+  // VendorGuid
+  //
+  if (VariableInfo->Header.VendorGuid != NULL) {
+    CopyGuid (
+      VariableInfo->Header.VendorGuid,
+      GetVendorGuidPtr (VariablePtr, AuthFlag)
+      );
+  } else {
+    VariableInfo->Header.VendorGuid = GetVendorGuidPtr (VariablePtr, AuthFlag);
+  }
+
+  //
+  // VariableName
+  //
+  NameSize = NameSizeOfVariable (VariablePtr, AuthFlag);
+  if (  (VariableInfo->Header.VariableName != NULL)
+     && (VariableInfo->Header.NameSize >= NameSize))
+  {
+    CopyMem (
+      VariableInfo->Header.VariableName,
+      GetVariableNamePtr (VariablePtr, AuthFlag),
+      NameSize
+      );
+  } else if (VariableInfo->Header.VariableName != NULL) {
+    return EFI_BUFFER_TOO_SMALL;
+  } else {
+    VariableInfo->Header.VariableName = GetVariableNamePtr (VariablePtr, AuthFlag);
+  }
+
+  //
+  // Data
+  //
+  DataSize = DataSizeOfVariable (VariablePtr, AuthFlag);
+  if (  (VariableInfo->Header.Data != NULL)
+     && (VariableInfo->Header.DataSize >= DataSize))
+  {
+    CopyMem (
+      VariableInfo->Header.Data,
+      GetVariableDataPtr (VariablePtr, AuthFlag),
+      NameSize
+      );
+  } else if (VariableInfo->Header.Data != NULL) {
+    return EFI_BUFFER_TOO_SMALL;
+  } else {
+    VariableInfo->Header.Data = GetVariableDataPtr (VariablePtr, AuthFlag);
+  }
+
+  //
+  // Update size information about name & data.
+  //
+  VariableInfo->Header.NameSize = NameSize;
+  VariableInfo->Header.DataSize = DataSize;
+
+  return EFI_SUCCESS;
+}
+
+/**
+
+  Retrieve details of the variable next to given variable within VariableStore.
+
+  If VarInfo->Address is NULL, the first one in VariableStore is returned.
+
+  VariableStart and/or VariableEnd can be given optionally for the situation
+  in which the valid storage space is smaller than the VariableStore->Size.
+  This usually happens when PEI variable services make a compact variable
+  cache to save memory, which cannot make use VariableStore->Size to determine
+  the correct variable storage range.
+
+  @param[in,out] VariableInfo             Pointer to variable information.
+
+  @retval EFI_INVALID_PARAMETER  VariableInfo or VariableStore is NULL.
+  @retval EFI_NOT_FOUND          If the end of VariableStore is reached.
+  @retval EFI_SUCCESS            The next variable is retrieved successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+GetNextVariableInfo (
+  IN OUT  PROTECTED_VARIABLE_INFO  *VariableInfo
+  )
+{
+  VARIABLE_STORE_HEADER  *VarStore;
+  VARIABLE_HEADER        *VariablePtr;
+  VARIABLE_HEADER        *VariableStart;
+  VARIABLE_HEADER        *VariableEnd;
+  BOOLEAN                AuthFlag;
+
+  if (VariableInfo == NULL) {
+    ASSERT (VariableInfo != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  if (mNvVariableCache != NULL) {
+    VarStore = mNvVariableCache;
+  } else if (mVariableModuleGlobal != NULL) {
+    VarStore = (VARIABLE_STORE_HEADER *)(UINTN)
+               mVariableModuleGlobal->VariableGlobal.NonVolatileVariableBase;
+  } else {
+    return EFI_NOT_FOUND;
+  }
+
+  VariableStart = GetStartPointer (VarStore);
+  VariableEnd   = GetEndPointer (VarStore);
+
+  if ((VariableInfo->Flags.Auth != TRUE) && (VariableInfo->Flags.Auth != FALSE)) {
+    VariableInfo->Flags.Auth = CompareGuid (
+                                 &VarStore->Signature,
+                                 &gEfiAuthenticatedVariableGuid
+                                 );
+  }
+
+  AuthFlag = VariableInfo->Flags.Auth;
+
+  if (VariableInfo->StoreIndex == VAR_INDEX_INVALID) {
+    VariablePtr = VariableStart;
+  } else {
+    VariablePtr = (VARIABLE_HEADER *)
+                  ((UINTN)VarStore + (UINTN)VariableInfo->StoreIndex);
+    if (VariablePtr >= VariableEnd) {
+      return EFI_NOT_FOUND;
+    }
+
+    VariablePtr = GetNextVariablePtr (VariablePtr, AuthFlag);
+  }
+
+  if (!IsValidVariableHeader (VariablePtr, VariableEnd, AuthFlag)) {
+    return EFI_NOT_FOUND;
+  }
+
+  VariableInfo->StoreIndex = (UINTN)VariablePtr - (UINTN)VarStore;
+  return GetVariableInfo (VariableInfo);
+}
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeCache.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeCache.c
index 9bb30bc1e804..dc319feee727 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeCache.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeCache.c
@@ -7,7 +7,7 @@
   This external input must be validated carefully to avoid security issue like
   buffer overflow, integer overflow.
 
-Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2019 - 2022, Intel Corporation. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c
index 517cae7b00f8..c2b689f6202d 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c
@@ -14,7 +14,7 @@
   VariableServiceSetVariable(), VariableServiceQueryVariableInfo(), ReclaimForOS(),
   SmmVariableGetStatistics() should also do validation based on its own knowledge.
 
-Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2010 - 2022, Intel Corporation. All rights reserved.<BR>
 Copyright (c) 2018, Linaro, Ltd. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
@@ -1045,6 +1045,13 @@ VariableWriteServiceInitializeSmm (
 {
   EFI_STATUS  Status;
 
+  Status = ProtectedVariableLibWriteInit ();
+  if (EFI_ERROR (Status) && (Status != EFI_UNSUPPORTED)) {
+    DEBUG ((DEBUG_ERROR, "Variable protection service: write-init failed. Status = %r\n", Status));
+    ASSERT_EFI_ERROR (Status);
+    return;
+  }
+
   Status = VariableWriteServiceInitialize ();
   if (EFI_ERROR (Status)) {
     DEBUG ((DEBUG_ERROR, "Variable write service initialization failed. Status = %r\n", Status));
@@ -1143,10 +1150,32 @@ MmVariableServiceInitialize (
   VOID
   )
 {
-  EFI_STATUS  Status;
-  EFI_HANDLE  VariableHandle;
-  VOID        *SmmFtwRegistration;
-  VOID        *SmmEndOfDxeRegistration;
+  EFI_STATUS                     Status;
+  EFI_HANDLE                     VariableHandle;
+  VOID                           *SmmFtwRegistration;
+  VOID                           *SmmEndOfDxeRegistration;
+  PROTECTED_VARIABLE_CONTEXT_IN  ContextIn;
+
+  //
+  // Initialize protected variable service, if enabled.
+  //
+  ContextIn.StructSize    = sizeof (ContextIn);
+  ContextIn.StructVersion = PROTECTED_VARIABLE_CONTEXT_IN_STRUCT_VERSION;
+
+  ContextIn.FindVariableSmm     = NULL;
+  ContextIn.GetVariableInfo     = GetVariableInfo;
+  ContextIn.GetNextVariableInfo = GetNextVariableInfo;
+  ContextIn.UpdateVariableStore = VariableExLibUpdateNvVariable;
+  ContextIn.UpdateVariable      = VariableExLibUpdateVariable;
+
+  ContextIn.MaxVariableSize     = (UINT32)GetMaxVariableSize ();
+  ContextIn.VariableServiceUser = FromSmmModule;
+
+  Status = ProtectedVariableLibInitialize (&ContextIn);
+  if (EFI_ERROR (Status) && (Status != EFI_UNSUPPORTED)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
 
   //
   // Variable initialize.
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.c
index 4aaeb5ba8806..8fb8679671ad 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.c
@@ -13,7 +13,7 @@
 
   InitCommunicateBuffer() is really function to check the variable data size.
 
-Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2010 - 2022, Intel Corporation. All rights reserved.<BR>
 Copyright (c) Microsoft Corporation.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
@@ -36,11 +36,13 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 #include <Library/UefiLib.h>
 #include <Library/BaseLib.h>
 #include <Library/MmUnblockMemoryLib.h>
+#include <Library/IoLib.h>
 
 #include <Guid/EventGroup.h>
 #include <Guid/SmmVariableCommon.h>
 
 #include "PrivilegePolymorphic.h"
+#include "Variable.h"
 #include "VariableParsing.h"
 
 EFI_HANDLE                      mHandle                              = NULL;
@@ -53,6 +55,8 @@ VARIABLE_INFO_ENTRY             *mVariableInfo                       = NULL;
 VARIABLE_STORE_HEADER           *mVariableRuntimeHobCacheBuffer      = NULL;
 VARIABLE_STORE_HEADER           *mVariableRuntimeNvCacheBuffer       = NULL;
 VARIABLE_STORE_HEADER           *mVariableRuntimeVolatileCacheBuffer = NULL;
+VARIABLE_STORE_HEADER           *mNvVariableCache                    = NULL;
+VARIABLE_MODULE_GLOBAL          *mVariableModuleGlobal               = NULL;
 UINTN                           mVariableBufferSize;
 UINTN                           mVariableRuntimeHobCacheBufferSize;
 UINTN                           mVariableRuntimeNvCacheBufferSize;
@@ -616,7 +620,6 @@ FindVariableInRuntimeCache (
   )
 {
   EFI_STATUS              Status;
-  UINTN                   TempDataSize;
   VARIABLE_POINTER_TRACK  RtPtrTrack;
   VARIABLE_STORE_TYPE     StoreType;
   VARIABLE_STORE_HEADER   *VariableStoreList[VariableStoreTypeMax];
@@ -669,31 +672,23 @@ FindVariableInRuntimeCache (
       //
       // Get data size
       //
-      TempDataSize = DataSizeOfVariable (RtPtrTrack.CurrPtr, mVariableAuthFormat);
-      ASSERT (TempDataSize != 0);
-
-      if (*DataSize >= TempDataSize) {
-        if (Data == NULL) {
-          Status = EFI_INVALID_PARAMETER;
-          goto Done;
-        }
-
-        CopyMem (Data, GetVariableDataPtr (RtPtrTrack.CurrPtr, mVariableAuthFormat), TempDataSize);
-        *DataSize = TempDataSize;
-
-        UpdateVariableInfo (VariableName, VendorGuid, RtPtrTrack.Volatile, TRUE, FALSE, FALSE, TRUE, &mVariableInfo);
-
-        Status = EFI_SUCCESS;
-        goto Done;
-      } else {
-        *DataSize = TempDataSize;
-        Status    = EFI_BUFFER_TOO_SMALL;
-        goto Done;
+      if (!RtPtrTrack.Volatile) {
+        //
+        // Currently only non-volatile variable needs protection.
+        //
+        Status = ProtectedVariableLibGetByBuffer (RtPtrTrack.CurrPtr, Data, (UINT32 *)DataSize, mVariableAuthFormat);
+      }
+
+      if (RtPtrTrack.Volatile || (Status == EFI_UNSUPPORTED)) {
+        Status = GetVariableData (RtPtrTrack.CurrPtr, Data, (UINT32 *)DataSize, mVariableAuthFormat);
+      }
+
+      if (!EFI_ERROR (Status)) {
+        UpdateVariableInfo (VariableName, VendorGuid, RtPtrTrack.Volatile, TRUE, FALSE, FALSE, FALSE, &mVariableInfo);
       }
     }
   }
 
-Done:
   if ((Status == EFI_SUCCESS) || (Status == EFI_BUFFER_TOO_SMALL)) {
     if ((Attributes != NULL) && (RtPtrTrack.CurrPtr != NULL)) {
       *Attributes = RtPtrTrack.CurrPtr->Attributes;
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 10/28] SecurityPkg: Add new KeyService types and defines
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (8 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 09/28] MdeModulePkg: Add support for Protected Variables Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-22 14:06   ` Wang, Jian J
  2022-04-29 18:04 ` [Patch v2 11/28] SecurityPkg: Update RPMC APIs with index Judah Vang
                   ` (19 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Jiewen Yao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add new KeyService types and defines.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 SecurityPkg/Include/Ppi/KeyServicePpi.h | 57 ++++++++++++++++++++
 1 file changed, 57 insertions(+)

diff --git a/SecurityPkg/Include/Ppi/KeyServicePpi.h b/SecurityPkg/Include/Ppi/KeyServicePpi.h
new file mode 100644
index 000000000000..f126913d2d81
--- /dev/null
+++ b/SecurityPkg/Include/Ppi/KeyServicePpi.h
@@ -0,0 +1,57 @@
+/** @file
+  Provides Key Services.
+
+Copyright (c) 2008 - 2018, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+@par Specification Reference:
+**/
+
+#ifndef PEI_KEY_SERVICE_PPI_H_
+#define PEI_KEY_SERVICE_PPI_H_
+///
+/// KEY SERVICE PPI GUID
+///
+extern EFI_GUID  gKeyServicePpiGuid;
+
+/**
+  Generate a new key from root key.
+
+  @param[in]   Salt                     Pointer to the salt(non-secret) value.
+  @param[in]   SaltSize                 Salt size in bytes.
+  @param[out]  NewKey                   Pointer to buffer to receive new key.
+  @param[in]   NewKeySize               Size of new key bytes to generate.
+
+  @retval EFI_SUCCESS                   The function completed successfully
+  @retval OTHER                         The function completed with failure.
+**/
+typedef
+EFI_STATUS
+(EFIAPI *KEY_SERVICE_GEN_KEY)(
+  IN   UINT8        *Salt,
+  IN   UINTN        SaltSize,
+  OUT  UINT8        *NewKey,
+  IN   UINTN        NewKeySize
+  );
+
+#define KEY_SERVICE_PPI_REVISION  1
+#define ROOT_KEY_LEN              64
+#define SALT_SIZE_MIN_LEN         64
+#define KEY_SERVICE_KEY_NAME      L"KEY_SERVICE_KEY"
+
+typedef struct {
+  UINT8    RootKey[ROOT_KEY_LEN];
+  UINT8    PreviousRootKey[ROOT_KEY_LEN];
+} KEY_SERVICE_DATA;
+
+typedef struct _KEY_SERVICE_PPI KEY_SERVICE_PPI;
+
+///
+/// KEY SERVICE PPI
+/// The interface functions are for Key Service in PEI Phase
+///
+struct _KEY_SERVICE_PPI {
+  KEY_SERVICE_GEN_KEY    GenerateKey; /// Generate Key
+};
+
+#endif
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 11/28] SecurityPkg: Update RPMC APIs with index
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (9 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 10/28] SecurityPkg: Add new KeyService types and defines Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-22 14:07   ` Wang, Jian J
  2022-04-29 18:04 ` [Patch v2 12/28] SecurityPkg: Add new variable types and functions Judah Vang
                   ` (18 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Jiewen Yao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Update RPMC APIs with index parameter because sometimes
there are more than 1 RPMC counter on the platform.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 SecurityPkg/Library/RpmcLibNull/RpmcLibNull.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/SecurityPkg/Library/RpmcLibNull/RpmcLibNull.c b/SecurityPkg/Library/RpmcLibNull/RpmcLibNull.c
index 792e48250e5d..557aeb6abf09 100644
--- a/SecurityPkg/Library/RpmcLibNull/RpmcLibNull.c
+++ b/SecurityPkg/Library/RpmcLibNull/RpmcLibNull.c
@@ -1,7 +1,7 @@
 /** @file
   NULL RpmcLib instance for build purpose.
 
-Copyright (c) 2020, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2020 - 2022, Intel Corporation. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
@@ -12,6 +12,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 /**
   Requests the monotonic counter from the designated RPMC counter.
 
+  @param[in]    CounterIndex            The RPMC index
   @param[out]   CounterValue            A pointer to a buffer to store the RPMC value.
 
   @retval       EFI_SUCCESS             The operation completed successfully.
@@ -21,6 +22,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 EFI_STATUS
 EFIAPI
 RequestMonotonicCounter (
+  IN  UINT8   CounterIndex,
   OUT UINT32  *CounterValue
   )
 {
@@ -31,6 +33,8 @@ RequestMonotonicCounter (
 /**
   Increments the monotonic counter in the SPI flash device by 1.
 
+  @param[in]    CounterIndex            The RPMC index
+
   @retval       EFI_SUCCESS             The operation completed successfully.
   @retval       EFI_DEVICE_ERROR        A device error occurred while attempting to update the counter.
   @retval       EFI_UNSUPPORTED         The operation is un-supported.
@@ -38,7 +42,7 @@ RequestMonotonicCounter (
 EFI_STATUS
 EFIAPI
 IncrementMonotonicCounter (
-  VOID
+  IN  UINT8  CounterIndex
   )
 {
   ASSERT (FALSE);
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 12/28] SecurityPkg: Add new variable types and functions
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (10 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 11/28] SecurityPkg: Update RPMC APIs with index Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-22 14:12   ` Wang, Jian J
  2022-04-29 18:04 ` [Patch v2 13/28] SecurityPkg: Fix GetVariableKey API Judah Vang
                   ` (17 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Jiewen Yao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add new variable encryption/decryption function prototypes.
Add new variable digest structure. Add new Protected
variable function prototypes. Update RPMC APIs to Add
an index because there is could more than one counter.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 SecurityPkg/Include/Library/RpmcLib.h        | 15 +++++---
 SecurityPkg/Include/Library/VariableKeyLib.h | 37 +++-----------------
 2 files changed, 16 insertions(+), 36 deletions(-)

diff --git a/SecurityPkg/Include/Library/RpmcLib.h b/SecurityPkg/Include/Library/RpmcLib.h
index df4ba34ba8cf..cb71dfcd7e4d 100644
--- a/SecurityPkg/Include/Library/RpmcLib.h
+++ b/SecurityPkg/Include/Library/RpmcLib.h
@@ -1,19 +1,23 @@
 /** @file
   Public definitions for the Replay Protected Monotonic Counter (RPMC) Library.
 
-Copyright (c) 2020, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2020 - 2022, Intel Corporation. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
-#ifndef _RPMC_LIB_H_
-#define _RPMC_LIB_H_
+#ifndef RPMC_LIB_H_
+#define RPMC_LIB_H_
 
 #include <Uefi/UefiBaseType.h>
 
+#define RPMC_COUNTER_1  0
+#define RPMC_COUNTER_2  1
+
 /**
   Requests the monotonic counter from the designated RPMC counter.
 
+  @param[in]    CounterIndex            The RPMC index
   @param[out]   CounterValue            A pointer to a buffer to store the RPMC value.
 
   @retval       EFI_SUCCESS             The operation completed successfully.
@@ -23,12 +27,15 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 EFI_STATUS
 EFIAPI
 RequestMonotonicCounter (
+  IN  UINT8   CounterIndex,
   OUT UINT32  *CounterValue
   );
 
 /**
   Increments the monotonic counter in the SPI flash device by 1.
 
+  @param[in]    CounterIndex            The RPMC index
+
   @retval       EFI_SUCCESS             The operation completed successfully.
   @retval       EFI_DEVICE_ERROR        A device error occurred while attempting to update the counter.
   @retval       EFI_UNSUPPORTED         The operation is un-supported.
@@ -36,7 +43,7 @@ RequestMonotonicCounter (
 EFI_STATUS
 EFIAPI
 IncrementMonotonicCounter (
-  VOID
+  IN  UINT8  CounterIndex
   );
 
 #endif
diff --git a/SecurityPkg/Include/Library/VariableKeyLib.h b/SecurityPkg/Include/Library/VariableKeyLib.h
index 561ebad09da2..6076c4d4731b 100644
--- a/SecurityPkg/Include/Library/VariableKeyLib.h
+++ b/SecurityPkg/Include/Library/VariableKeyLib.h
@@ -1,13 +1,13 @@
 /** @file
   Public definitions for Variable Key Library.
 
-Copyright (c) 2020, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2020 - 2022, Intel Corporation. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
-#ifndef _VARIABLE_KEY_LIB_H_
-#define _VARIABLE_KEY_LIB_H_
+#ifndef VARIABLE_KEY_LIB_H_
+#define VARIABLE_KEY_LIB_H_
 
 #include <Uefi/UefiBaseType.h>
 
@@ -25,35 +25,8 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 EFI_STATUS
 EFIAPI
 GetVariableKey (
-  OUT VOID       **VariableKey,
-  IN  OUT UINTN  *VariableKeySize
-  );
-
-/**
-  Regenerates the variable key.
-
-  @retval       EFI_SUCCESS             The variable key was regenerated successfully.
-  @retval       EFI_DEVICE_ERROR        An error occurred while attempting to regenerate the key.
-  @retval       EFI_ACCESS_DENIED       The function was invoked after locking the key interface.
-  @retval       EFI_UNSUPPORTED         Key regeneration is not supported in the current boot configuration.
-**/
-EFI_STATUS
-EFIAPI
-RegenerateVariableKey (
-  VOID
-  );
-
-/**
-  Locks the regenerate key interface.
-
-  @retval       EFI_SUCCESS             The key interface was locked successfully.
-  @retval       EFI_UNSUPPORTED         Locking the key interface is not supported in the current boot configuration.
-  @retval       Others                  An error occurred while attempting to lock the key interface.
-**/
-EFI_STATUS
-EFIAPI
-LockVariableKeyInterface (
-  VOID
+  OUT VOID   *VariableKey,
+  IN  UINTN  VariableKeySize
   );
 
 #endif
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 13/28] SecurityPkg: Fix GetVariableKey API
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (11 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 12/28] SecurityPkg: Add new variable types and functions Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-22 14:15   ` Wang, Jian J
  2022-04-29 18:04 ` [Patch v2 14/28] SecurityPkg: Add null encryption variable libs Judah Vang
                   ` (16 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Jiewen Yao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Fix GetVariableKey API to match changes in header files.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.c b/SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.c
index a08def767b5f..cfbad54ba106 100644
--- a/SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.c
+++ b/SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.c
@@ -1,7 +1,7 @@
 /** @file
   Null version of VariableKeyLib for build purpose. Don't use it in real product.
 
-Copyright (c) 2020, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2020 - 2022, Intel Corporation. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
@@ -22,8 +22,8 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 EFI_STATUS
 EFIAPI
 GetVariableKey (
-  OUT VOID       **VariableKey,
-  IN  OUT UINTN  *VariableKeySize
+  OUT VOID   *VariableKey,
+  IN  UINTN  VariableKeySize
   )
 {
   ASSERT (FALSE);
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 14/28] SecurityPkg: Add null encryption variable libs
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (12 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 13/28] SecurityPkg: Fix GetVariableKey API Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-22 14:20   ` Wang, Jian J
  2022-04-29 18:04 ` [Patch v2 15/28] SecurityPkg: Add VariableKey library function Judah Vang
                   ` (15 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Jiewen Yao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Provide null ecryption variable libraries.
These will be used by default for platforms that don't
support protected variable encryption.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf |  38 +++++++
 SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariable.c          | 107 ++++++++++++++++++++
 SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.uni |  16 +++
 3 files changed, 161 insertions(+)

diff --git a/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf b/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf
new file mode 100644
index 000000000000..ff5631b336eb
--- /dev/null
+++ b/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf
@@ -0,0 +1,38 @@
+## @file
+#  Provides NULL version of encryption variable services.
+#
+#  Copyright (c) 2015 - 2022, Intel Corporation. All rights reserved.<BR>
+#
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010005
+  BASE_NAME                      = EncryptionVariableLibNull
+  MODULE_UNI_FILE                = EncryptionVariableLib.uni
+  FILE_GUID                      = 3972E6FE-74D5-45C3-A9FB-DB9E5E5C9C17
+  MODULE_TYPE                    = BASE
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = EncryptionVariableLib
+
+#
+# The following information is for reference only and not required by the build tools.
+#
+#  VALID_ARCHITECTURES           = IA32 X64
+#
+
+[Sources]
+  EncryptionVariable.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+  SecurityPkg/SecurityPkg.dec
+
+[LibraryClasses]
+  BaseLib
+  DebugLib
+
+[Guids]
+
diff --git a/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariable.c b/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariable.c
new file mode 100644
index 000000000000..58a4ae9f4282
--- /dev/null
+++ b/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariable.c
@@ -0,0 +1,107 @@
+/** @file
+  The common variable operation routines shared by DXE_RUNTIME variable
+  module and DXE_SMM variable module.
+
+  Caution: This module requires additional review when modified.
+  This driver will have external input - variable data. They may be input in SMM mode.
+  This external input must be validated carefully to avoid security issue like
+  buffer overflow, integer overflow.
+
+  VariableServiceGetNextVariableName () and VariableServiceQueryVariableInfo() are external API.
+  They need check input parameter.
+
+  VariableServiceGetVariable() and VariableServiceSetVariable() are external API
+  to receive datasize and data buffer. The size should be checked carefully.
+
+  VariableServiceSetVariable() should also check authenticate data to avoid buffer overflow,
+  integer overflow. It should also check attribute to avoid authentication bypass.
+
+Copyright (c) 2019 - 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Uefi.h>
+
+#include <Library/EncryptionVariableLib.h>
+#include <Library/DebugLib.h>
+
+/**
+  Encrypt variable data.
+
+  Null version.
+
+  @param[in, out]   VarEncInfo   Pointer to structure containing detailed
+                                 information about a variable.
+
+  @retval EFI_UNSUPPORTED         Unsupported to encrypt variable.
+
+**/
+EFI_STATUS
+EFIAPI
+EncryptVariable (
+  IN OUT VARIABLE_ENCRYPTION_INFO  *VarEncInfo
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+  Decrypt variable data.
+
+  Null version.
+
+  @param[in, out]   VarEncInfo   Pointer to structure containing detailed
+                                 information about a variable.
+
+  @retval EFI_UNSUPPORTED         Unsupported to encrypt variable.
+
+**/
+EFI_STATUS
+EFIAPI
+DecryptVariable (
+  IN OUT VARIABLE_ENCRYPTION_INFO  *VarEncInfo
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+  Get cipher information.
+
+  Null version.
+
+  @param[in]   VarEncInfo   Pointer to structure containing detailed
+                            information about a variable.
+
+  @retval EFI_UNSUPPORTED         Unsupported interface.
+
+**/
+EFI_STATUS
+EFIAPI
+GetCipherDataInfo (
+  IN VARIABLE_ENCRYPTION_INFO  *VarEncInfo
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+  Set cipher information for a variable.
+
+  Null version.
+
+  @param[in]   VarEncInfo   Pointer to structure containing detailed
+                            information about a variable.
+
+  @retval EFI_UNSUPPORTED         If this method is not supported.
+
+**/
+EFI_STATUS
+EFIAPI
+SetCipherDataInfo (
+  IN VARIABLE_ENCRYPTION_INFO  *VarEncInfo
+  )
+{
+  return EFI_UNSUPPORTED;
+}
diff --git a/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.uni b/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.uni
new file mode 100644
index 000000000000..856fa201b8df
--- /dev/null
+++ b/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.uni
@@ -0,0 +1,16 @@
+// /** @file
+// Provides authenticated variable services.
+//
+// Provides authenticated variable services.
+//
+// Copyright (c) 2015 - 2022, Intel Corporation. All rights reserved.<BR>
+//
+// SPDX-License-Identifier: BSD-2-Clause-Patent
+//
+// **/
+
+
+#string STR_MODULE_ABSTRACT             #language en-US "Provides authenticated variable services"
+
+#string STR_MODULE_DESCRIPTION          #language en-US "Provides authenticated variable services."
+
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 15/28] SecurityPkg: Add VariableKey library function
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (13 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 14/28] SecurityPkg: Add null encryption variable libs Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-04-29 18:04 ` [Patch v2 16/28] SecurityPkg: Add EncryptionVariable lib with AES Judah Vang
                   ` (14 subsequent siblings)
  29 siblings, 0 replies; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Jiewen Yao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Provide function that retrieves the key for protected
variables.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 SecurityPkg/Library/VariableKeyLib/VariableKeyLib.inf | 36 ++++++++++++
 SecurityPkg/Library/VariableKeyLib/VariableKeyLib.c   | 59 ++++++++++++++++++++
 2 files changed, 95 insertions(+)

diff --git a/SecurityPkg/Library/VariableKeyLib/VariableKeyLib.inf b/SecurityPkg/Library/VariableKeyLib/VariableKeyLib.inf
new file mode 100644
index 000000000000..f62c80ce9943
--- /dev/null
+++ b/SecurityPkg/Library/VariableKeyLib/VariableKeyLib.inf
@@ -0,0 +1,36 @@
+## @file
+#  Provides default implementation of VariableKeyLib.
+#
+#  Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010029
+  BASE_NAME                      = VariableKeyLib
+  FILE_GUID                      = 7DF5A0BA-1DBB-4E67-A9F7-9FCCB1F9D250
+  MODULE_TYPE                    = BASE
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = VariableKeyLib
+
+#
+# The following information is for reference only and not required by the build tools.
+#
+#  VALID_ARCHITECTURES           = IA32 X64 Arm AArch64
+#
+
+[Sources]
+  VariableKeyLib.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+  SecurityPkg/SecurityPkg.dec
+
+[LibraryClasses]
+  BaseLib
+  DebugLib
+
+[PpiS]
+  gKeyServicePpiGuid ## CONSUMES
+
diff --git a/SecurityPkg/Library/VariableKeyLib/VariableKeyLib.c b/SecurityPkg/Library/VariableKeyLib/VariableKeyLib.c
new file mode 100644
index 000000000000..31b22782cb0c
--- /dev/null
+++ b/SecurityPkg/Library/VariableKeyLib/VariableKeyLib.c
@@ -0,0 +1,59 @@
+/** @file
+  VariableKeyLib implementation.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <PiPei.h>
+
+#include <Library/PeiServicesLib.h>
+#include <Library/DebugLib.h>
+#include <Library/VariableKeyLib.h>
+
+#include <Ppi/KeyServicePpi.h>
+
+#define VAR_KEY_SALT       L"Key for RPMC Variable"
+#define VAR_KEY_SALT_SIZE  sizeof (VAR_KEY_SALT)
+
+/**
+  Retrieves the key for integrity and/or confidentiality of variables.
+
+  @param[out]     VariableKey         A pointer to pointer for the variable key buffer.
+  @param[in]      VariableKeySize     The size in bytes of the variable key.
+
+  @retval       EFI_SUCCESS             The variable key was returned.
+  @retval       EFI_DEVICE_ERROR        An error occurred while attempting to get the variable key.
+  @retval       EFI_ACCESS_DENIED       The function was invoked after locking the key interface.
+  @retval       EFI_UNSUPPORTED         The variable key is not supported in the current boot configuration.
+**/
+EFI_STATUS
+EFIAPI
+GetVariableKey (
+  OUT VOID   *VariableKey,
+  IN  UINTN  VariableKeySize
+  )
+{
+  EFI_STATUS       Status;
+  KEY_SERVICE_PPI  *KeyService;
+
+  Status = PeiServicesLocatePpi (
+             &gKeyServicePpiGuid,
+             0,
+             NULL,
+             (void **)&KeyService
+             );
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
+  Status = KeyService->GenerateKey (
+                         (UINT8 *)VAR_KEY_SALT,
+                         VAR_KEY_SALT_SIZE,
+                         VariableKey,
+                         VariableKeySize
+                         );
+  return Status;
+}
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 16/28] SecurityPkg: Add EncryptionVariable lib with AES
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (14 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 15/28] SecurityPkg: Add VariableKey library function Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-04-29 18:04 ` [Patch v2 17/28] SecurityPkg: Add Protected Variable Services Judah Vang
                   ` (13 subsequent siblings)
  29 siblings, 0 replies; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Jiewen Yao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add encryption/decryption of protected variable functionality.
Add functions to get/set cipher data of a protected variable.
This is use for supporting confidentiality for protected
variables.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 SecurityPkg/Library/EncryptionVariableLib/EncryptionVariableLib.inf |  43 ++
 SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.h      |  49 ++
 SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.c      | 728 ++++++++++++++++++++
 3 files changed, 820 insertions(+)

diff --git a/SecurityPkg/Library/EncryptionVariableLib/EncryptionVariableLib.inf b/SecurityPkg/Library/EncryptionVariableLib/EncryptionVariableLib.inf
new file mode 100644
index 000000000000..7ece52f2fb58
--- /dev/null
+++ b/SecurityPkg/Library/EncryptionVariableLib/EncryptionVariableLib.inf
@@ -0,0 +1,43 @@
+## @file
+#  Provides variable encryption/decryption services.
+#
+#  Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+#
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010029
+  BASE_NAME                      = EncryptionVariableLib
+  FILE_GUID                      = 459E2CB0-AF4B-4415-B6A1-335E71FD8B85
+  MODULE_TYPE                    = BASE
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = EncryptionVariableLib
+
+#
+# The following information is for reference only and not required by the build tools.
+#
+#  VALID_ARCHITECTURES           = IA32 X64
+#
+
+[Sources]
+  EncryptionVariable.c
+  EncryptionVariable.h
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+  SecurityPkg/SecurityPkg.dec
+  CryptoPkg/CryptoPkg.dec
+
+[LibraryClasses]
+  BaseLib
+  BaseMemoryLib
+  DebugLib
+  MemoryAllocationLib
+  BaseCryptLib
+
+[Guids]
+  gEfiVariableGuid
+  gEfiAuthenticatedVariableGuid
diff --git a/SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.h b/SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.h
new file mode 100644
index 000000000000..f35f9f9e3ad7
--- /dev/null
+++ b/SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.h
@@ -0,0 +1,49 @@
+/** @file
+  Definitions used by this library implementation.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef ENCRYPTION_VARIABLE_H_
+#define ENCRYPTION_VARIABLE_H_
+
+#define ENC_KEY_SEP        L":"
+#define ENC_KEY_SEP_SIZE   2
+#define ENC_KEY_NAME       L"VAR_ENC_KEY"
+#define ENC_KEY_NAME_SIZE  22
+
+#define ENC_KEY_SIZE    (256/8)
+#define ENC_BLOCK_SIZE  AES_BLOCK_SIZE
+#define ENC_IVEC_SIZE   ENC_BLOCK_SIZE
+
+#define ENC_PADDING_BYTE  0x0F
+
+//
+// PKCS#5 padding
+//
+// #define AES_CIPHER_DATA_SIZE(PlainDataSize)
+//  (AES_BLOCK_SIZE + (PlainDataSize)) & (~(AES_BLOCK_SIZE - 1))
+//
+#define AES_CIPHER_DATA_SIZE(PlainDataSize)  ALIGN_VALUE (PlainDataSize, AES_BLOCK_SIZE)
+
+#define FREE_POOL(Address)      \
+    if ((Address) != NULL) {    \
+      FreePool (Address);       \
+      (Address) = NULL;         \
+    }
+
+#pragma pack(1)
+
+typedef struct {
+  UINT32    DataType;         // SYM_TYPE_AES
+  UINT32    HeaderSize;       // sizeof(VARIABLE_ENCRYPTION_HEADER)
+  UINT32    PlainDataSize;    // Plain data size
+  UINT32    CipherDataSize;   // Cipher data size
+  UINT8     KeyIvec[ENC_IVEC_SIZE];
+} VARIABLE_ENCRYPTION_HEADER;
+
+#pragma pack()
+
+#endif // _ENCRYPTION_VARIABLE_H_
diff --git a/SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.c b/SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.c
new file mode 100644
index 000000000000..58ffb09e0373
--- /dev/null
+++ b/SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.c
@@ -0,0 +1,728 @@
+/** @file
+  Implementation of EncryptionVariableLib with AES algorithm support.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Uefi.h>
+
+#include <Guid/VariableFormat.h>
+#include <Library/EncryptionVariableLib.h>
+#include <Library/BaseCryptLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/DebugLib.h>
+
+#include "EncryptionVariable.h"
+
+/**
+  Derive encryption key for given variable from variable root key.
+
+  The derivation algorithm is depicted below
+
+    HKDF_Expand(SHA256, RootKey, Name||':'||Guid||':'||Attr||"VAR_ENC_KEY")
+
+  @param[in]    VarEncInfo    Pointer to structure containing detailed
+                              information about a variable.
+  @param[in]    EncKeySize    Size of key requested.
+  @param[out]   EncKey        Buffer of key.
+
+  @retval TRUE    The key was derived successfully.
+  @retval FALSE   Failed to generate encryption key.
+
+**/
+STATIC
+BOOLEAN
+EncVarLibGenEncKey (
+  IN VARIABLE_ENCRYPTION_INFO  *VarEncInfo,
+  IN UINTN                     EncKeySize,
+  OUT UINT8                    *EncKey
+  )
+{
+  BOOLEAN  Status;
+
+  struct {
+    VOID     *Data;
+    UINTN    Size;
+  }                 InfoGroup[6];
+  UINT8  *Info;
+  UINTN  InfoSize;
+  UINTN  Index;
+  UINT8  Salt[16];
+
+  //
+  // info: Name||':'||Guid||':'||Attr||"VAR_ENC_KEY"
+  //
+  InfoGroup[0].Size = VarEncInfo->Header.NameSize;
+  InfoGroup[0].Data = VarEncInfo->Header.VariableName;
+
+  InfoGroup[1].Size = ENC_KEY_SEP_SIZE;
+  InfoGroup[1].Data = ENC_KEY_SEP;
+
+  InfoGroup[2].Size = sizeof (*VarEncInfo->Header.VendorGuid);
+  InfoGroup[2].Data = VarEncInfo->Header.VendorGuid;
+
+  InfoGroup[3].Size = ENC_KEY_SEP_SIZE;
+  InfoGroup[3].Data = ENC_KEY_SEP;
+
+  InfoGroup[4].Size = sizeof (VarEncInfo->Header.Attributes);
+  InfoGroup[4].Data = &VarEncInfo->Header.Attributes;
+
+  InfoGroup[5].Size = ENC_KEY_NAME_SIZE;
+  InfoGroup[5].Data = ENC_KEY_NAME;
+
+  for (InfoSize = 0, Index = 0; Index < ARRAY_SIZE (InfoGroup); ++Index) {
+    InfoSize += InfoGroup[Index].Size;
+  }
+
+  Info = AllocateZeroPool (InfoSize);
+  if (Info == NULL) {
+    ASSERT (Info != NULL);
+    return FALSE;
+  }
+
+  for (InfoSize = 0, Index = 0; Index < ARRAY_SIZE (InfoGroup); ++Index) {
+    CopyMem (Info + InfoSize, InfoGroup[Index].Data, InfoGroup[Index].Size);
+    InfoSize += InfoGroup[Index].Size;
+  }
+
+  Status = HkdfSha256ExtractAndExpand (
+             VarEncInfo->Key,
+             VarEncInfo->KeySize,
+             Salt,
+             0,
+             Info,
+             InfoSize,
+             EncKey,
+             EncKeySize
+             );
+
+  FreePool (Info);
+
+  return Status;
+}
+
+/**
+  Generate init-vector for AES encryption.
+
+  @param[out]   InitVector  IVEC buffer.
+  @param[in]    Size        Size of IVEC requested.
+
+  @retval TRUE    IVEC was generated successfully.
+  @retval FALSE   Failed to generate IVEC.
+
+**/
+STATIC
+BOOLEAN
+EncVarLibGenIvec (
+  OUT UINT8  *InitVector,
+  IN  UINTN  Size
+  )
+{
+  return RandomBytes (InitVector, Size);
+}
+
+/**
+  Check if there's valid variable information needed by encrypting or decrypting.
+
+  @param[in]    VarEncInfo    Buffer conveying details about a variable.
+  @param[in]    CheckForEnc   Flag indicating check for encrypting (TRUE) or
+                              decrypting (FALSE).
+
+  @retval TRUE    VarEncInfo is valid.
+  @retval FALSE   VarEncInfo is invalid.
+
+**/
+STATIC
+BOOLEAN
+IsValidVariableInfo (
+  IN VARIABLE_ENCRYPTION_INFO  *VarEncInfo,
+  IN BOOLEAN                   CheckForEnc
+  )
+{
+  BOOLEAN  Valid;
+
+  if (CheckForEnc) {
+    Valid = (VarEncInfo->Header.Data != NULL && VarEncInfo->Header.DataSize > 0)
+            || (VarEncInfo->PlainData != NULL && VarEncInfo->PlainDataSize > 0);
+    if (!Valid) {
+      ASSERT (
+        (VarEncInfo->Header.Data != NULL && VarEncInfo->Header.DataSize > 0)
+             || (VarEncInfo->PlainData != NULL && VarEncInfo->PlainDataSize > 0)
+        );
+    }
+  } else {
+    Valid = (VarEncInfo->Header.Data != NULL && VarEncInfo->Header.DataSize > 0)
+            || (VarEncInfo->CipherData != NULL && VarEncInfo->CipherDataSize > 0);
+    if (!Valid) {
+      ASSERT (
+        (VarEncInfo->Header.Data != NULL && VarEncInfo->Header.DataSize > 0)
+             || (VarEncInfo->CipherData != NULL && VarEncInfo->CipherDataSize > 0)
+        );
+    }
+  }
+
+  Valid = Valid
+          && VarEncInfo->Header.VariableName != NULL
+          && VarEncInfo->Header.NameSize > 0
+          && VarEncInfo->Header.VendorGuid != NULL
+          && VarEncInfo->Key != NULL
+          && VarEncInfo->KeySize > 0;
+  if (!Valid) {
+    ASSERT (VarEncInfo->Header.VariableName != NULL);
+    ASSERT (VarEncInfo->Header.NameSize != 0);
+    ASSERT (VarEncInfo->Header.VendorGuid != NULL);
+    ASSERT (VarEncInfo->Key != NULL);
+    ASSERT (VarEncInfo->KeySize > 0);
+  }
+
+  return Valid;
+}
+
+/**
+  Sanity check of encrption header prefixed to encrypted data.
+
+  @param[in]    EncHeader   Pointer to VARIABLE_ENCRYPTION_HEADER.
+  @param[in]    DataSize    Size of variable data payload.
+
+  @retval TRUE    EncHeader is valid.
+  @retval FALSE   EncHeader is invalid.
+
+**/
+STATIC
+BOOLEAN
+IsValidEncrptionHeader (
+  IN VARIABLE_ENCRYPTION_HEADER  *EncHeader,
+  IN UINT32                      DataSize
+  )
+{
+  if (  (DataSize > sizeof (VARIABLE_ENCRYPTION_HEADER))
+     && ((EncHeader->DataType == ENC_TYPE_AES) || (EncHeader->DataType == ENC_TYPE_NULL))
+     && (EncHeader->HeaderSize >= sizeof (VARIABLE_ENCRYPTION_HEADER))
+     && (EncHeader->CipherDataSize > 0)
+     && ((EncHeader->CipherDataSize % ENC_BLOCK_SIZE) == 0)
+     && (EncHeader->PlainDataSize > 0)
+     && (EncHeader->PlainDataSize <= EncHeader->CipherDataSize)
+     && ((EncHeader->CipherDataSize + EncHeader->HeaderSize) <= DataSize))
+  {
+    return TRUE;
+  }
+
+  return FALSE;
+}
+
+/**
+  Encrypt variable data.
+
+  If VarEncInfo->PlainData is not NULL, VarEncInfo->PlainData holds the plain
+  data. Otherwise, VarEncInfo->Headr.Data is supposed to be the plain data.
+
+  If VarEncInfo->CipherData is not NULL, The encrypted data is stored in
+  VarEncInfo->CipherData. Otherwise, the encrypted data is stored directly
+  in variable data buffer, i.e. VarEncInfo->Headr.Data.
+
+  @param[in, out]   VarEncInfo   Pointer to structure containing detailed
+                                 information about a variable.
+
+  @retval EFI_SUCCESS             Variable was encrypted successfully.
+  @retval EFI_INVALID_PARAMETER   Variable information in VarEncInfo is invalid.
+  @retval EFI_BUFFER_TOO_SMALL    VarEncInfo->CipherData is not NULL but
+                                  VarEncInfo->CipherDataSize is too small.
+  @retval EFI_ABORTED             Uknown error occurred during encrypting.
+  @retval EFI_OUT_OF_RESOURCES    Fail to allocate enough resource.
+  @retval EFI_UNSUPPORTED         Unsupported to encrypt variable.
+
+**/
+EFI_STATUS
+EFIAPI
+EncryptVariable (
+  IN OUT VARIABLE_ENCRYPTION_INFO  *VarEncInfo
+  )
+{
+  EFI_STATUS                  Status;
+  VOID                        *AesContext;
+  UINT8                       EncKey[ENC_KEY_SIZE];
+  UINT8                       Ivec[ENC_IVEC_SIZE];
+  UINT8                       *PlainBuffer;
+  UINT8                       *CipherBuffer;
+  UINT8                       *PlainData;
+  UINT32                      PlainDataSize;
+  VARIABLE_ENCRYPTION_HEADER  *CipherData;
+  UINT32                      CipherDataSize;
+  UINT32                      PaddingBytes;
+
+  Status       = EFI_ABORTED;
+  AesContext   = NULL;
+  PlainBuffer  = NULL;
+  CipherBuffer = NULL;
+
+  if (!IsValidVariableInfo (VarEncInfo, TRUE)) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  if (VarEncInfo->PlainData != NULL) {
+    PlainData     = VarEncInfo->PlainData;
+    PlainDataSize = VarEncInfo->PlainDataSize;
+  } else {
+    PlainData     = VarEncInfo->Header.Data;
+    PlainDataSize = (UINT32)VarEncInfo->Header.DataSize;
+  }
+
+  CipherDataSize = AES_CIPHER_DATA_SIZE (PlainDataSize);
+  if (VarEncInfo->CipherData != NULL) {
+    if (VarEncInfo->CipherDataSize
+        < (CipherDataSize + sizeof (VARIABLE_ENCRYPTION_HEADER)))
+    {
+      VarEncInfo->CipherDataSize = CipherDataSize
+                                   + sizeof (VARIABLE_ENCRYPTION_HEADER);
+      return EFI_BUFFER_TOO_SMALL;
+    }
+
+    CipherData = VarEncInfo->CipherData;
+  } else {
+    CipherData = VarEncInfo->Header.Data;
+  }
+
+  //
+  // Prepare buffer for encrypted data.
+  //
+  if ((UINTN)CipherData == (UINTN)PlainData) {
+    //
+    // Need buffer to store the encrypted data temporarily.
+    //
+    CipherBuffer = (UINT8 *)AllocateZeroPool (
+                              CipherDataSize
+                              + sizeof (VARIABLE_ENCRYPTION_HEADER)
+                              );
+    if (CipherBuffer == NULL) {
+      ASSERT (CipherBuffer != NULL);
+      return EFI_OUT_OF_RESOURCES;
+    }
+  } else {
+    CipherBuffer = (UINT8 *)CipherData;
+  }
+
+  //
+  // Plain variable data must also be multiple of ENC_BLOCK_SIZE.
+  //
+  PaddingBytes = ALIGN_VALUE (PlainDataSize, ENC_BLOCK_SIZE) - PlainDataSize;
+  if (PaddingBytes != 0) {
+    //
+    // Since the plain data size will be saved in the VARIABLE_ENCRYPTION_HEADER,
+    // there's no need to do PKCS way of padding. To save space, just padding
+    // the plain data to be of the nearest n*ENC_BLOCK_SIZE.
+    //
+    PlainBuffer = AllocateZeroPool (PlainDataSize + PaddingBytes);
+    if (PlainBuffer == NULL) {
+      ASSERT (PlainBuffer != NULL);
+      goto Done;
+    }
+
+    CopyMem (PlainBuffer, PlainData, PlainDataSize);
+    SetMem (PlainBuffer + PlainDataSize, PaddingBytes, ENC_PADDING_BYTE);
+  } else {
+    PlainBuffer = PlainData;
+  }
+
+  //
+  // Skip EFI_VARIABLE_APPEND_WRITE bit in generating encryption key.
+  //
+  VarEncInfo->Header.Attributes &= (~EFI_VARIABLE_APPEND_WRITE);
+  if (!EncVarLibGenEncKey (VarEncInfo, ENC_KEY_SIZE, EncKey)) {
+    ASSERT (FALSE);
+    return EFI_ABORTED;
+  }
+
+  if (!EncVarLibGenIvec (Ivec, ENC_IVEC_SIZE)) {
+    ASSERT (FALSE);
+    return EFI_ABORTED;
+  }
+
+  AesContext = AllocateZeroPool (AesGetContextSize ());
+  if (AesContext == NULL) {
+    ASSERT (AesContext != NULL);
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  if (!AesInit (AesContext, EncKey, ENC_KEY_SIZE * 8)) {
+    ASSERT (FALSE);
+    goto Done;
+  }
+
+  if (AesCbcEncrypt (
+        AesContext,
+        PlainBuffer,
+        PlainDataSize + PaddingBytes,
+        Ivec,
+        CipherBuffer + sizeof (VARIABLE_ENCRYPTION_HEADER)
+        ))
+  {
+    //
+    // Keep the IV for decryption.
+    //
+    CopyMem (CipherData->KeyIvec, Ivec, ENC_BLOCK_SIZE);
+
+    if ((UINTN)CipherBuffer != (UINTN)CipherData) {
+      CopyMem (
+        CipherData + 1,
+        CipherBuffer + sizeof (VARIABLE_ENCRYPTION_HEADER),
+        CipherDataSize
+        );
+    }
+
+    CipherData->CipherDataSize = CipherDataSize;
+    CipherData->PlainDataSize  = PlainDataSize;
+    CipherData->DataType       = ENC_TYPE_AES;
+    CipherData->HeaderSize     = sizeof (VARIABLE_ENCRYPTION_HEADER);
+
+    VarEncInfo->CipherData       = CipherData;
+    VarEncInfo->CipherDataSize   = CipherDataSize + sizeof (VARIABLE_ENCRYPTION_HEADER);
+    VarEncInfo->CipherHeaderSize = sizeof (VARIABLE_ENCRYPTION_HEADER);
+    VarEncInfo->CipherDataType   = ENC_TYPE_AES;
+
+    Status = EFI_SUCCESS;
+  } else {
+    VarEncInfo->CipherData       = NULL;
+    VarEncInfo->CipherDataSize   = 0;
+    VarEncInfo->CipherHeaderSize = 0;
+    VarEncInfo->CipherDataType   = ENC_TYPE_NULL;
+
+    ASSERT (FALSE);
+  }
+
+Done:
+  FREE_POOL (AesContext);
+  if (PlainBuffer != PlainData) {
+    FREE_POOL (PlainBuffer);
+  }
+
+  if (CipherBuffer != (UINT8 *)CipherData) {
+    FREE_POOL (CipherBuffer);
+  }
+
+  return Status;
+}
+
+/**
+  Decrypt variable data.
+
+  If VarEncInfo->CipherData is not NULL, it must holds the cipher data to be
+  decrypted. Otherwise, assume the cipher data from variable data buffer, i.e.
+  VarEncInfo->Header.Data.
+
+  If VarEncInfo->Flags.DecryptInPlace is TRUE, the decrypted data will be put
+  back in the same buffer as cipher buffer got above, after encryption header,
+  which helps to identify later if the data in buffer is decrypted or not. This
+  can avoid repeat decryption when accessing the same variable more than once.
+
+  If VarEncInfo->Flags.DecryptInPlace is FALSE, VarEncInfo->PlainData must be
+  passed in with a valid buffer with VarEncInfo->PlainDataSize set correctly
+  with its size.
+
+  Note the VarEncInfo->PlainData is always pointing to the buffer address with
+  decrypted data without encryption header, and VarEncInfo->PlainDataSize is
+  always the size of original variable data, if this function returned
+  successfully.
+
+  @param[in, out]   VarEncInfo   Pointer to structure containing detailed
+                                 information about a variable.
+
+  @retval EFI_SUCCESS             Variable was decrypted successfully.
+  @retval EFI_INVALID_PARAMETER   Variable information in VarEncInfo is invalid.
+  @retval EFI_BUFFER_TOO_SMALL    VarEncInfo->PlainData is not NULL but
+                                  VarEncInfo->PlainDataSize is too small.
+  @retval EFI_ABORTED             Uknown error occurred during decrypting.
+  @retval EFI_OUT_OF_RESOURCES    Fail to allocate enough resource.
+  @retval EFI_COMPROMISED_DATA    The cipher header is not valid.
+  @retval EFI_UNSUPPORTED         Unsupported to encrypt variable.
+
+**/
+EFI_STATUS
+EFIAPI
+DecryptVariable (
+  IN OUT VARIABLE_ENCRYPTION_INFO  *VarEncInfo
+  )
+{
+  VOID                        *AesContext;
+  UINT8                       EncKey[ENC_KEY_SIZE];
+  UINT8                       *PlainBuffer;
+  UINT8                       *PlainData;
+  VARIABLE_ENCRYPTION_HEADER  *CipherData;
+  UINT32                      CipherDataSize;
+  EFI_STATUS                  Status;
+
+  Status      = EFI_ABORTED;
+  AesContext  = NULL;
+  PlainBuffer = NULL;
+
+  if (!IsValidVariableInfo (VarEncInfo, FALSE)) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  if (VarEncInfo->CipherData != NULL) {
+    CipherData     = VarEncInfo->CipherData;
+    CipherDataSize = VarEncInfo->CipherDataSize;
+  } else {
+    CipherData     = VarEncInfo->Header.Data;
+    CipherDataSize = (UINT32)VarEncInfo->Header.DataSize;
+  }
+
+  //
+  // Sanity check of cipher header.
+  //
+  if (!IsValidEncrptionHeader (CipherData, CipherDataSize)) {
+    return EFI_COMPROMISED_DATA;
+  }
+
+  if (  (VarEncInfo->PlainData != NULL)
+     && (VarEncInfo->PlainDataSize < CipherData->PlainDataSize))
+  {
+    VarEncInfo->PlainDataSize = CipherData->PlainDataSize;
+    return EFI_BUFFER_TOO_SMALL;
+  }
+
+  if (CipherData->DataType == ENC_TYPE_AES) {
+    if (VarEncInfo->Flags.DecryptInPlace) {
+      //
+      // Reusing cipher data buffer needs to keep the encryption header.
+      //
+      PlainData = (UINT8 *)CipherData + CipherData->HeaderSize;
+    } else {
+      PlainData = VarEncInfo->PlainData;
+    }
+
+    if (PlainData == NULL) {
+      return EFI_INVALID_PARAMETER;
+    }
+
+    //
+    // Always need buffer to store the decrypted data temporarily, due to
+    // padding bytes or buffer reuse. Then the buffer must be larger than
+    // CipherData->PlainDataSize.
+    //
+    PlainBuffer = AllocatePages (EFI_SIZE_TO_PAGES (CipherDataSize));
+    if (PlainBuffer == NULL) {
+      ASSERT (PlainBuffer != NULL);
+      return EFI_OUT_OF_RESOURCES;
+    }
+
+    if (!EncVarLibGenEncKey (VarEncInfo, ENC_KEY_SIZE, EncKey)) {
+      ASSERT (FALSE);
+      goto Done;
+    }
+
+    AesContext = AllocatePages (EFI_SIZE_TO_PAGES (AesGetContextSize ()));
+    if (AesContext == NULL) {
+      ASSERT (AesContext != NULL);
+      Status = EFI_OUT_OF_RESOURCES;
+      goto Done;
+    }
+
+    if (!AesInit (AesContext, EncKey, ENC_KEY_SIZE * 8)) {
+      ASSERT (FALSE);
+      goto Done;
+    }
+
+    if (AesCbcDecrypt (
+          AesContext,
+          (UINT8 *)CipherData + CipherData->HeaderSize,
+          CipherDataSize - CipherData->HeaderSize,
+          CipherData->KeyIvec,
+          PlainBuffer
+          ))
+    {
+      Status = EFI_SUCCESS;
+    } else {
+      Status = EFI_COMPROMISED_DATA;
+    }
+  } else {
+    //
+    // The data has been decrypted already.
+    //
+    PlainBuffer = (UINT8 *)CipherData + CipherData->HeaderSize;
+
+    if (VarEncInfo->PlainData != NULL) {
+      PlainData = VarEncInfo->PlainData;
+    } else {
+      PlainData = PlainBuffer;
+    }
+
+    Status = EFI_SUCCESS;
+  }
+
+  if (!EFI_ERROR (Status)) {
+    if (PlainBuffer != PlainData) {
+      CopyMem (PlainData, PlainBuffer, CipherData->PlainDataSize);
+    }
+
+    if (VarEncInfo->PlainData != NULL) {
+      if (VarEncInfo->PlainData != PlainBuffer) {
+        CopyMem (VarEncInfo->PlainData, PlainBuffer, CipherData->PlainDataSize);
+      }
+    } else {
+      VarEncInfo->PlainData = PlainData;
+    }
+
+    VarEncInfo->PlainDataSize    = CipherData->PlainDataSize;
+    VarEncInfo->CipherHeaderSize = CipherData->HeaderSize;
+    VarEncInfo->CipherDataType   = CipherData->DataType;
+
+    if (VarEncInfo->Flags.DecryptInPlace) {
+      CipherData->DataType = ENC_TYPE_NULL;
+    }
+  }
+
+Done:
+  FreePages (PlainBuffer, EFI_SIZE_TO_PAGES ((CipherDataSize)));
+  FreePages (AesContext, EFI_SIZE_TO_PAGES (AesGetContextSize ()));
+  return Status;
+}
+
+/**
+  Get cipher information about a variable, including plaindata size,
+  cipher algorithm type, etc.
+
+  For data passed in with VarEncInfo,
+
+    VarEncInfo->Header.Data
+      - The variable data in normal variable structure.
+    VarEncInfo->Header.DataSize
+      - The size of variable data.
+
+  For data passed out with VarEncInfo (valid only if EFI_SUCCESS is returned),
+
+    VarEncInfo->CipherDataType
+      - ENC_TYPE_NULL, if the variable is not encrypted or has been decrypted;
+      - ENC_TYPE_AES, if the variable is encrypted.
+    VarEncInfo->CipherHeaderSize
+      - Size of cipher header put before encrypted or decrypted data.
+    VarEncInfo->PlainData
+      - NULL, if the variable is encrypted; Or
+      - pointer to original variable data, if the variable has been decrypted.
+    VarEncInfo->PlainDataSize
+      - The size of original variable data
+    VarEncInfo->CipherData
+      - NULL, if the variable is decrypted; Or
+      - pointer to start of encrypted variable data, including encryption header;
+    VarEncInfo->CipherDataSize
+      - The size of encrypted variable data, including encryption header.
+
+  @param[in]   VarEncInfo   Pointer to structure containing detailed
+                            information about a variable.
+
+  @retval EFI_SUCCESS             The information was retrieved successfully.
+  @retval EFI_INVALID_PARAMETER   Variable information in VarEncInfo is invalid.
+  @retval EFI_NOT_FOUND           No cipher information recognized.
+  @retval EFI_UNSUPPORTED         Unsupported interface.
+
+**/
+EFI_STATUS
+EFIAPI
+GetCipherDataInfo (
+  IN VARIABLE_ENCRYPTION_INFO  *VarEncInfo
+  )
+{
+  VARIABLE_ENCRYPTION_HEADER  *EncHeader;
+
+  if ((VarEncInfo->Header.Data == NULL) || (VarEncInfo->Header.DataSize == 0)) {
+    ASSERT (VarEncInfo->Header.Data != NULL);
+    ASSERT (VarEncInfo->Header.DataSize != 0);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // Validate encryption header.
+  //
+  EncHeader = (VARIABLE_ENCRYPTION_HEADER *)VarEncInfo->Header.Data;
+  if (!IsValidEncrptionHeader (EncHeader, (UINT32)VarEncInfo->Header.DataSize)) {
+    //
+    // Not an encrypted variable.
+    //
+    return EFI_NOT_FOUND;
+  }
+
+  if (EncHeader->DataType == ENC_TYPE_NULL) {
+    //
+    // The data must have been decrypted.
+    //
+    VarEncInfo->PlainData            = (UINT8 *)VarEncInfo->Header.Data + EncHeader->HeaderSize;
+    VarEncInfo->CipherData           = NULL;
+    VarEncInfo->Flags.DecryptInPlace = TRUE;
+  } else {
+    //
+    // The data is encrypted.
+    //
+    VarEncInfo->CipherData           = VarEncInfo->Header.Data;
+    VarEncInfo->PlainData            = NULL;
+    VarEncInfo->Flags.DecryptInPlace = FALSE;
+  }
+
+  VarEncInfo->PlainDataSize    = EncHeader->PlainDataSize;
+  VarEncInfo->CipherDataSize   = EncHeader->CipherDataSize + EncHeader->HeaderSize;
+  VarEncInfo->CipherDataType   = EncHeader->DataType;
+  VarEncInfo->CipherHeaderSize = EncHeader->HeaderSize;
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Force set cipher information for a variable, like plaindata size,
+  cipher algorithm type, cipher data etc.
+
+  The destination buffer must be passed via VarEncInfo->Header.Data.
+
+  This method is only used to update and/or change plain data information.
+
+  @param[in]   VarEncInfo   Pointer to structure containing detailed
+                            information about a variable.
+
+  @retval EFI_SUCCESS             The information was updated successfully.
+  @retval EFI_INVALID_PARAMETER   Variable information in VarEncInfo is invalid.
+  @retval EFI_UNSUPPORTED         If this method is not supported.
+
+**/
+EFI_STATUS
+EFIAPI
+SetCipherDataInfo (
+  IN VARIABLE_ENCRYPTION_INFO  *VarEncInfo
+  )
+{
+  VARIABLE_ENCRYPTION_HEADER  *EncHeader;
+  UINT8                       *Data;
+
+  if (  (VarEncInfo->Header.Data == NULL)
+     || (VarEncInfo->Header.DataSize < sizeof (VARIABLE_ENCRYPTION_HEADER))
+     || (VarEncInfo->CipherDataType != ENC_TYPE_NULL))
+  {
+    ASSERT (VarEncInfo->Header.Data != NULL);
+    ASSERT (VarEncInfo->Header.DataSize >= sizeof (VARIABLE_ENCRYPTION_HEADER));
+    ASSERT (VarEncInfo->CipherDataType == ENC_TYPE_NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Data      = VarEncInfo->Header.Data;
+  EncHeader = (VARIABLE_ENCRYPTION_HEADER *)Data;
+
+  if (  !IsValidEncrptionHeader (EncHeader, (UINT32)VarEncInfo->Header.DataSize)
+     || (VarEncInfo->PlainDataSize > EncHeader->CipherDataSize))
+  {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  if ((VarEncInfo->PlainData != NULL) && (VarEncInfo->PlainDataSize > 0)) {
+    CopyMem (
+      Data + EncHeader->HeaderSize,
+      VarEncInfo->PlainData,
+      VarEncInfo->PlainDataSize
+      );
+  }
+
+  EncHeader->DataType = VarEncInfo->CipherDataType;
+  if (VarEncInfo->PlainDataSize != 0) {
+    EncHeader->PlainDataSize = VarEncInfo->PlainDataSize;
+  }
+
+  return EFI_SUCCESS;
+}
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 17/28] SecurityPkg: Add Protected Variable Services
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (15 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 16/28] SecurityPkg: Add EncryptionVariable lib with AES Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-04-29 18:04 ` [Patch v2 18/28] MdeModulePkg: Reference Null ProtectedVariableLib Judah Vang
                   ` (12 subsequent siblings)
  29 siblings, 0 replies; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Jiewen Yao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add Protected Variable Services across the different UEFI phases.
Functions includes creating variable digest, performing integrity
check, initializing protected variables, updating protected
variables, and verifying the MetaDataHmacVar variable.
This module prevents UEFI variable tampering.  It provides
variable integrity and confidentiality.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 SecurityPkg/Library/ProtectedVariableLib/DxeProtectedVariableLib.inf        |   64 +
 SecurityPkg/Library/ProtectedVariableLib/PeiProtectedVariableLib.inf        |   68 +
 SecurityPkg/Library/ProtectedVariableLib/SmmProtectedVariableLib.inf        |   67 +
 SecurityPkg/Library/ProtectedVariableLib/SmmRuntimeProtectedVariableLib.inf |   62 +
 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableInternal.h        |  611 ++++++
 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableCommon.c          | 2095 ++++++++++++++++++++
 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableDxe.c             |  163 ++
 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariablePei.c             | 1331 +++++++++++++
 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmm.c             |  209 ++
 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmDxeCommon.c    |  975 +++++++++
 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmRuntime.c      |  233 +++
 11 files changed, 5878 insertions(+)

diff --git a/SecurityPkg/Library/ProtectedVariableLib/DxeProtectedVariableLib.inf b/SecurityPkg/Library/ProtectedVariableLib/DxeProtectedVariableLib.inf
new file mode 100644
index 000000000000..74a0285af7ef
--- /dev/null
+++ b/SecurityPkg/Library/ProtectedVariableLib/DxeProtectedVariableLib.inf
@@ -0,0 +1,64 @@
+## @file
+#  Provides protected variable services for EmulatorPkg.
+#
+#  Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010029
+  BASE_NAME                      = DxeProtectedVariableLib
+  MODULE_UNI_FILE                = ProtectedVariableLib.uni
+  FILE_GUID                      = 6F424E10-0F75-4716-9F97-58C2E1C643AD
+  MODULE_TYPE                    = DXE_RUNTIME_DRIVER
+  VERSION_STRING                 = 0.1
+  LIBRARY_CLASS                  = ProtectedVariableLib|DXE_RUNTIME_DRIVER
+
+#
+# The following information is for reference only and not required by the build tools.
+#
+#  VALID_ARCHITECTURES           = IA32 X64
+#
+
+[Sources]
+  ProtectedVariableDxe.c
+  ProtectedVariableCommon.c
+  ProtectedVariableSmmDxeCommon.c
+  ProtectedVariableInternal.h
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+  SecurityPkg/SecurityPkg.dec
+  CryptoPkg/CryptoPkg.dec
+
+[LibraryClasses]
+  BaseLib
+  BaseMemoryLib
+  DebugLib
+  MemoryAllocationLib
+  HobLib
+  BaseCryptLib
+  EncryptionVariableLib
+  RpmcLib
+  HashApiLib
+  SortLib
+
+[Protocols]
+  gEfiVariableWriteArchProtocolGuid
+
+[Guids]
+  gEdkiiMetaDataHmacVariableGuid
+  gEdkiiProtectedVariableGlobalGuid
+  gEdkiiVarErrorFlagGuid
+  gEdkiiProtectedVariableContextGuid
+
+[Pcd]
+  gEfiSecurityPkgTokenSpaceGuid.PcdPlatformVariableName
+  gEfiSecurityPkgTokenSpaceGuid.PcdPlatformVariableGuid
+  gEfiSecurityPkgTokenSpaceGuid.PcdProtectedVariableIntegrity
+  gEfiSecurityPkgTokenSpaceGuid.PcdProtectedVariableConfidentiality
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxAuthVariableSize
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxHardwareErrorVariableSize
diff --git a/SecurityPkg/Library/ProtectedVariableLib/PeiProtectedVariableLib.inf b/SecurityPkg/Library/ProtectedVariableLib/PeiProtectedVariableLib.inf
new file mode 100644
index 000000000000..44c959a94ca3
--- /dev/null
+++ b/SecurityPkg/Library/ProtectedVariableLib/PeiProtectedVariableLib.inf
@@ -0,0 +1,68 @@
+## @file
+#  Provides protected variable services.
+#
+#  Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010029
+  BASE_NAME                      = PeiProtectedVariableLib
+  MODULE_UNI_FILE                = ProtectedVariableLib.uni
+  FILE_GUID                      = 76FBFBCE-ACBB-4084-A348-8FCC97AAEB9D
+  MODULE_TYPE                    = PEIM
+  VERSION_STRING                 = 0.1
+  LIBRARY_CLASS                  = ProtectedVariableLib|PEIM
+
+#
+# The following information is for reference only and not required by the build tools.
+#
+#  VALID_ARCHITECTURES           = IA32 X64 AARCH64
+#
+
+[Sources]
+  ProtectedVariablePei.c
+  ProtectedVariableCommon.c
+  ProtectedVariableInternal.h
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+  SecurityPkg/SecurityPkg.dec
+  CryptoPkg/CryptoPkg.dec
+
+[LibraryClasses]
+  BaseLib
+  BaseMemoryLib
+  DebugLib
+  MemoryAllocationLib
+  HobLib
+  BaseCryptLib
+  RpmcLib
+  VariableKeyLib
+  EncryptionVariableLib
+  ReportStatusCodeLib
+  PeiServicesLib
+  HashApiLib
+  SortLib
+
+[Guids]
+  gEdkiiMetaDataHmacVariableGuid
+  gEdkiiProtectedVariableGlobalGuid
+  gEdkiiVarErrorFlagGuid
+  gEdkiiProtectedVariableContextGuid
+
+[Ppis]
+  gEfiPeiMemoryDiscoveredPpiGuid
+  gEfiPeiVariableStoreDiscoveredPpiGuid
+
+[Pcd]
+  gEfiSecurityPkgTokenSpaceGuid.PcdStatusCodeVariableIntegrity
+  gEfiSecurityPkgTokenSpaceGuid.PcdPlatformVariableName
+  gEfiSecurityPkgTokenSpaceGuid.PcdPlatformVariableGuid
+  gEfiSecurityPkgTokenSpaceGuid.PcdProtectedVariableIntegrity
+  gEfiSecurityPkgTokenSpaceGuid.PcdProtectedVariableConfidentiality
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxAuthVariableSize
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxHardwareErrorVariableSize
diff --git a/SecurityPkg/Library/ProtectedVariableLib/SmmProtectedVariableLib.inf b/SecurityPkg/Library/ProtectedVariableLib/SmmProtectedVariableLib.inf
new file mode 100644
index 000000000000..ecf0b1a43d30
--- /dev/null
+++ b/SecurityPkg/Library/ProtectedVariableLib/SmmProtectedVariableLib.inf
@@ -0,0 +1,67 @@
+## @file
+#  Provides protected variable services.
+#
+#  Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010029
+  BASE_NAME                      = SmmProtectedVariableLib
+  MODULE_UNI_FILE                = ProtectedVariableLib.uni
+  FILE_GUID                      = 2BEE71E5-259B-4057-A2C1-2115DF43C76A
+  MODULE_TYPE                    = DXE_SMM_DRIVER
+  VERSION_STRING                 = 0.1
+  LIBRARY_CLASS                  = ProtectedVariableLib|DXE_SMM_DRIVER MM_STANDALONE
+
+#
+# The following information is for reference only and not required by the build tools.
+#
+#  VALID_ARCHITECTURES           = IA32 X64
+#
+
+[Sources]
+  ProtectedVariableSmm.c
+  ProtectedVariableCommon.c
+  ProtectedVariableSmmDxeCommon.c
+  ProtectedVariableInternal.h
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+  SecurityPkg/SecurityPkg.dec
+  CryptoPkg/CryptoPkg.dec
+
+[LibraryClasses]
+  BaseLib
+  BaseMemoryLib
+  DebugLib
+  MemoryAllocationLib
+  HobLib
+  BaseCryptLib
+  EncryptionVariableLib
+  RpmcLib
+  VariableKeyLib
+  HashApiLib
+  SortLib
+
+[Protocols]
+  gEfiMmEndOfDxeProtocolGuid
+
+[Guids]
+  gSmmVariableWriteGuid
+  gEdkiiMetaDataHmacVariableGuid
+  gEdkiiProtectedVariableGlobalGuid
+  gEdkiiVarErrorFlagGuid
+  gEdkiiProtectedVariableContextGuid
+
+[Pcd]
+  gEfiSecurityPkgTokenSpaceGuid.PcdPlatformVariableName
+  gEfiSecurityPkgTokenSpaceGuid.PcdPlatformVariableGuid
+  gEfiSecurityPkgTokenSpaceGuid.PcdProtectedVariableIntegrity
+  gEfiSecurityPkgTokenSpaceGuid.PcdProtectedVariableConfidentiality
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxAuthVariableSize
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxHardwareErrorVariableSize
+
diff --git a/SecurityPkg/Library/ProtectedVariableLib/SmmRuntimeProtectedVariableLib.inf b/SecurityPkg/Library/ProtectedVariableLib/SmmRuntimeProtectedVariableLib.inf
new file mode 100644
index 000000000000..011ccdce2db8
--- /dev/null
+++ b/SecurityPkg/Library/ProtectedVariableLib/SmmRuntimeProtectedVariableLib.inf
@@ -0,0 +1,62 @@
+## @file
+#  Provides protected variable services.
+#
+#  Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010029
+  BASE_NAME                      = SmmRuntimeProtectedVariableLib
+  MODULE_UNI_FILE                = ProtectedVariableLib.uni
+  FILE_GUID                      = 99A623DE-1AD3-4AB3-909D-E3AADD7845EF
+  MODULE_TYPE                    = DXE_RUNTIME_DRIVER
+  VERSION_STRING                 = 0.1
+  LIBRARY_CLASS                  = ProtectedVariableLib|DXE_DRIVER DXE_RUNTIME_DRIVER
+
+#
+# The following information is for reference only and not required by the build tools.
+#
+#  VALID_ARCHITECTURES           = IA32 X64
+#
+
+[Sources]
+  ProtectedVariableSmmRuntime.c
+  ProtectedVariableCommon.c
+  ProtectedVariableInternal.h
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+  SecurityPkg/SecurityPkg.dec
+  CryptoPkg/CryptoPkg.dec
+
+[LibraryClasses]
+  BaseLib
+  BaseMemoryLib
+  DebugLib
+  MemoryAllocationLib
+  HobLib
+  BaseCryptLib
+  EncryptionVariableLib
+  RpmcLib
+  HashApiLib
+  SortLib
+
+[Guids]
+  gEfiEventVirtualAddressChangeGuid
+  gEdkiiMetaDataHmacVariableGuid
+  gEdkiiProtectedVariableGlobalGuid
+  gEdkiiVarErrorFlagGuid
+  gEdkiiProtectedVariableContextGuid
+
+[Pcd]
+  gEfiSecurityPkgTokenSpaceGuid.PcdPlatformVariableName
+  gEfiSecurityPkgTokenSpaceGuid.PcdPlatformVariableGuid
+  gEfiSecurityPkgTokenSpaceGuid.PcdProtectedVariableIntegrity
+  gEfiSecurityPkgTokenSpaceGuid.PcdProtectedVariableConfidentiality
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxAuthVariableSize
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxHardwareErrorVariableSize
+
diff --git a/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableInternal.h b/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableInternal.h
new file mode 100644
index 000000000000..fd38b5bd2019
--- /dev/null
+++ b/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableInternal.h
@@ -0,0 +1,611 @@
+/** @file
+  Definitions shared among different implementation of ProtectedVariableLib.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef PROTECTED_VARIABLE_INTERNAL_H_
+#define PROTECTED_VARIABLE_INTERNAL_H_
+
+#include <Guid/VariableFormat.h>
+#include <Guid/ProtectedVariable.h>
+
+#include <Library/DebugLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/BaseCryptLib.h>
+#include <Library/RpmcLib.h>
+#include <Library/VariableKeyLib.h>
+#include <Library/EncryptionVariableLib.h>
+#include <Library/ProtectedVariableLib.h>
+#include <Library/HashApiLib.h>
+
+#define VARIABLE_KEY_SIZE  (256/8)
+
+#define METADATA_HMAC_SIZE           (256/8)
+#define METADATA_HMAC_KEY_NAME       L"HMAC_KEY"
+#define METADATA_HMAC_KEY_NAME_SIZE  0x10
+
+#define METADATA_HMAC_SEP       L":"
+#define METADATA_HMAC_SEP_SIZE  2
+
+#define METADATA_HMAC_VARIABLE_NAME       L"MetaDataHmacVar"
+#define METADATA_HMAC_VARIABLE_NAME_SIZE  sizeof (METADATA_HMAC_VARIABLE_NAME)
+#define METADATA_HMAC_VARIABLE_GUID       gEdkiiMetaDataHmacVariableGuid
+#define METADATA_HMAC_VARIABLE_ATTR       VARIABLE_ATTRIBUTE_NV_BS_RT
+
+#define DIGEST_CONTEXT_SIZE  (HashApiGetContextSize())
+
+#define MAX_VARIABLE_SIZE                                                       \
+  MAX (MAX (PcdGet32 (PcdMaxVariableSize), PcdGet32 (PcdMaxAuthVariableSize)),  \
+       PcdGet32 (PcdMaxHardwareErrorVariableSize))
+
+#define IS_VARIABLE(Var, Name, Guid)          \
+  (StrCmp ((Var)->VariableName, (Name)) == 0  \
+   && CompareGuid ((CONST EFI_GUID *)(Var)->VendorGuid, (CONST EFI_GUID *)(Guid)))
+
+#define VARIABLE_SIZE(VarInfo)                                  \
+  (((UINTN)(VarInfo)->Header.Data - (UINTN)(VarInfo)->Buffer)   \
+   + (VarInfo)->Header.DataSize                                 \
+   + GET_PAD_SIZE ((VarInfo)->Header.DataSize))
+
+#define VARIABLE_HEADER_SIZE(AuthFlag)                    \
+  ((AuthFlag) ? sizeof (AUTHENTICATED_VARIABLE_HEADER)    \
+              : sizeof (VARIABLE_HEADER))
+
+#define VARIABLE_NAME(Var, AuthFlag)                    \
+  ((CHAR16 *)((UINTN)(Var) + VARIABLE_HEADER_SIZE(AuthFlag)))
+
+#define VARIABLE_START(VarStore)  \
+   ((VARIABLE_HEADER *)HEADER_ALIGN ((VARIABLE_STORE_HEADER *)(VarStore) + 1))
+
+#define VARIABLE_END(VarStore)                         \
+   ((VARIABLE_HEADER *)HEADER_ALIGN ((UINTN)(VarStore) \
+     + ((VARIABLE_STORE_HEADER *)(VarStore))->Size))
+
+#define SET_VARIABLE_DATA_SIZE(VarInfo, Size)                                 \
+  if ((VarInfo)->Flags.Auth) {                                                \
+    ((AUTHENTICATED_VARIABLE_HEADER *)((VarInfo)->Buffer))->DataSize = Size;  \
+    (VarInfo)->Header.DataSize = Size;                                        \
+  } else {                                                                    \
+    ((VARIABLE_HEADER *)((VarInfo)->Buffer))->DataSize = Size;                \
+      (VarInfo)->Header.DataSize = Size;                                      \
+  }
+
+#define IS_KNOWN_UNPROTECTED_VARIABLE(Global, VarInfo)  \
+  (CheckKnownUnprotectedVariable ((Global), (VarInfo)) < UnprotectedVarIndexMax)
+
+#define GET_CNTX(Global)   ((PROTECTED_VARIABLE_CONTEXT_IN *)(UINTN)((Global)->ContextIn))
+#define GET_BUFR(Address)  ((VOID *)(UINTN)(Address))
+#define GET_ADRS(Buffer)   ((EFI_PHYSICAL_ADDRESS)(UINTN)(Buffer))
+
+typedef struct _VARIABLE_IDENTIFIER {
+  CHAR16      *VariableName;
+  EFI_GUID    *VendorGuid;
+  UINT8       State;
+} VARIABLE_IDENTIFIER;
+
+typedef enum {
+  IndexHmacInDel = 0,     /// MetaDataHmacVar with state VAR_IN_DELETED_TRANSITION
+  IndexHmacAdded,         /// MetaDataHmacVar with state VAR_ADDED
+  IndexErrorFlag,         /// VarErrorFlag
+  IndexPlatformVar,       /// Platform Variable
+  UnprotectedVarIndexMax
+} UNPROTECTED_VARIABLE_INDEX;
+
+#pragma pack(1)
+
+#define PROTECTED_VARIABLE_CONTEXT_OUT_STRUCT_VERSION  0x02
+
+typedef struct _PROTECTED_VARIABLE_FLAG {
+  BOOLEAN    Auth;          // Authenticated variable format
+  BOOLEAN    WriteInit;     // Write-init-done
+  BOOLEAN    WriteReady;    // Ready-to-write
+  BOOLEAN    RecoveryMode;  // Variable storage recovery or provisioning
+  BOOLEAN    CacheReady;    // Indicates Cache is available
+  BOOLEAN    Reserved;      // reserved
+} PROTECTED_VARIABLE_FLAG;
+
+typedef struct _PROTECTED_VARIABLE_GLOBAL {
+  UINT32                     StructVersion;
+  UINT32                     StructSize;
+
+  ///
+  /// Variable root key used to derive Encryption key and HMAC key.
+  ///
+  UINT8                      RootKey[VARIABLE_KEY_SIZE];
+  ///
+  /// HMAC key derived from RootKey.
+  ///
+  UINT8                      MetaDataHmacKey[VARIABLE_KEY_SIZE];
+  ///
+  /// Number of variables in linked list pointed by VariableDigests.
+  ///
+  UINT32                     VariableNumber;
+  ///
+  /// Size of memory reserved by VariableCache.
+  ///
+  UINT32                     VariableCacheSize;
+  ///
+  /// Memory reserved to temporarily hold data of one variable, for integrity
+  /// validation purpose.
+  ///
+  EFI_PHYSICAL_ADDRESS       VariableCache;
+  ///
+  /// Pointer to linked list, in which each node holds the digest value of each
+  /// variable.
+  ///
+  EFI_PHYSICAL_ADDRESS       VariableDigests;
+  ///
+  /// Memory reserved for Context used in hash API to avoid repeat alloc/free.
+  ///
+  EFI_PHYSICAL_ADDRESS       DigestContext;
+  ///
+  /// Pointer to one of node in linked list pointed by VariableDigests, which
+  /// has been just accessed. This is mainly used to facilitate the two calls
+  /// use case of GetVariable().
+  ///
+  EFI_PHYSICAL_ADDRESS       LastAccessedVariable;
+  ///
+  /// Cached copy of pointers to nodes of unprotected variables in the linked
+  /// list pointed by VariableDigests.
+  ///
+  EFI_PHYSICAL_ADDRESS       Unprotected[UnprotectedVarIndexMax];
+  ///
+  /// Pointer to data structure holding helper functions passed by user of
+  /// ProtectedVariableLib, most of which are used to complete operations on
+  /// variable storage.
+  ///
+  EFI_PHYSICAL_ADDRESS       ContextIn;
+
+  ///
+  /// Pointer to Global data structure. This is to hold pre-mem address value.
+  /// Later to be used to identify pre-mem to post-mem transition.
+  ///
+  EFI_PHYSICAL_ADDRESS       GlobalSelf;
+
+  PROTECTED_VARIABLE_FLAG    Flags;
+} PROTECTED_VARIABLE_GLOBAL;
+
+#pragma pack()
+
+/* Sort method function pointer taking two parameters */
+typedef
+INTN
+(*SORT_METHOD) (
+  IN VARIABLE_DIGEST  *Variable1,
+  IN VARIABLE_DIGEST  *Variable2
+  );
+
+/* Update variable digest data function pointer */
+typedef
+BOOLEAN
+(*DIGEST_UPDATE) (
+  IN OUT  VOID   *Context,
+  IN      VOID   *Data,
+  IN      UINTN  DataSize
+  );
+
+/**
+
+  Print variable information
+
+  @param[in]   Data8      Pointer to data
+  @param[out]  DataSize   Size of data
+
+**/
+VOID
+PrintVariableData (
+  IN UINT8  *Data8,
+  IN UINTN  DataSize
+  );
+
+/**
+
+  Derive HMAC key from given variable root key.
+
+  @param[in]  RootKey       Pointer to root key to derive from.
+  @param[in]  RootKeySize   Size of root key.
+  @param[out] HmacKey       Pointer to generated HMAC key.
+  @param[in]  HmacKeySize   Size of HMAC key.
+
+  @retval TRUE      The HMAC key is derived successfully.
+  @retval FALSE     Failed to generate HMAC key from given root key.
+
+**/
+BOOLEAN
+EFIAPI
+GenerateMetaDataHmacKey (
+  IN   CONST UINT8  *RootKey,
+  IN   UINTN        RootKeySize,
+  OUT  UINT8        *HmacKey,
+  IN   UINTN        HmacKeySize
+  );
+
+/**
+
+  Digests the given variable data and updates HMAC context.
+
+  @param[in,out]  Context   Pointer to initialized HMAC context.
+  @param[in]      VarInfo   Pointer to variable data.
+
+  @retval TRUE    HMAC context was updated successfully.
+  @retval FALSE   Failed to update HMAC context.
+
+**/
+BOOLEAN
+UpdateVariableMetadataHmac (
+  IN  VOID                     *Context,
+  IN  PROTECTED_VARIABLE_INFO  *VarInfo
+  );
+
+/**
+
+  Re-calculate HMAC based on new variable data and re-generate MetaDataHmacVar.
+
+  @param[in]      Global          Pointer to global configuration data.
+  @param[in]      NewVarInfo      Pointer to buffer of new variable data.
+  @param[in,out]  NewHmacVarInfo  Pointer to buffer of new MetaDataHmacVar.
+
+  @return EFI_SUCCESS           The HMAC value was updated successfully.
+  @return EFI_ABORTED           Failed to calculate the HMAC value.
+  @return EFI_OUT_OF_RESOURCES  Not enough resource to calculate HMC value.
+  @return EFI_NOT_FOUND         The MetaDataHmacVar was not found in storage.
+
+**/
+EFI_STATUS
+RefreshVariableMetadataHmac (
+  IN      PROTECTED_VARIABLE_GLOBAL  *Global,
+  IN      PROTECTED_VARIABLE_INFO    *NewVarInfo,
+  IN  OUT PROTECTED_VARIABLE_INFO    *NewHmacVarInfo
+  );
+
+/**
+
+  Retrieve the context and global configuration data structure from HOB.
+
+  Once protected NV variable storage is cached and verified in PEI phase,
+  all related information are stored in a HOB which can be used by PEI variable
+  service itself and passed to SMM along with the boot flow, which can avoid
+  many duplicate works, like generating HMAC key, verifying NV variable storage,
+  etc.
+
+  The HOB can be identified by gEdkiiProtectedVariableGlobalGuid.
+
+  @param[out]   Global      Pointer to global configuration data from PEI phase.
+
+  @retval EFI_SUCCESS     The HOB was found, and Context and Global are retrieved.
+  @retval EFI_NOT_FOUND   The HOB was not found.
+
+**/
+EFI_STATUS
+EFIAPI
+GetProtectedVariableGlobalFromHob (
+  OUT PROTECTED_VARIABLE_GLOBAL  **Global OPTIONAL
+  );
+
+/**
+
+  Get context and/or global data structure used to process protected variable.
+
+  @param[out]   Global      Pointer to global configuration data.
+
+  @retval EFI_SUCCESS         Get requested structure successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+GetProtectedVariableGlobal (
+  OUT PROTECTED_VARIABLE_GLOBAL  **Global OPTIONAL
+  );
+
+/**
+
+  Get context data structure used to process protected variable.
+
+  @param[out]   ContextIn   Pointer to context provided by variable runtime services.
+
+  @retval EFI_SUCCESS         Get requested structure successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+GetProtectedVariableContext (
+  PROTECTED_VARIABLE_CONTEXT_IN  **ContextIn  OPTIONAL
+  );
+
+/**
+
+  Check if a given variable is unprotected variable specified in advance
+  and return its index ID.
+
+  @param[in] Global     Pointer to global configuration data.
+  @param[in] VarInfo    Pointer to variable information data.
+
+  @retval IndexHmacInDel    Variable is MetaDataHmacVar in delete-transition state.
+  @retval IndexHmacAdded    Variable is MetaDataHmacVar in valid state.
+  @retval IndexErrorFlag    Variable is VarErrorLog.
+  @retval Others            Variable is not any known unprotected variables.
+
+**/
+UNPROTECTED_VARIABLE_INDEX
+CheckKnownUnprotectedVariable (
+  IN  PROTECTED_VARIABLE_GLOBAL  *Global,
+  IN  PROTECTED_VARIABLE_INFO    *VarInfo
+  );
+
+/**
+
+  Return the size of variable MetaDataHmacVar.
+
+  @param[in] AuthFlag         Auth-variable indicator.
+
+  @retval size of variable MetaDataHmacVar.
+
+**/
+UINTN
+GetMetaDataHmacVarSize (
+  IN      BOOLEAN  AuthFlag
+  );
+
+/**
+
+  Fix state of MetaDataHmacVar on NV variable storage, if there's failure at
+  last boot during updating variable.
+
+  This must be done before the first writing of variable in current boot,
+  including storage reclaim.
+
+  @retval EFI_UNSUPPORTED        Updating NV variable storage is not supported.
+  @retval EFI_OUT_OF_RESOURCES   Not enough resource to complete the operation.
+  @retval EFI_SUCCESS            Variable store was successfully updated.
+
+**/
+EFI_STATUS
+FixupHmacVariable (
+  VOID
+  );
+
+/**
+
+  Verify the variable digest.
+
+  @param[in]  Global      Pointer to global configuration data.
+  @param[in]  VarInfo     Pointer to verified copy of protected variables.
+  @param[in]  VarDig      Pointer to variable digest data.
+
+  @retval EFI_INVALID_PARAMETER  Invalid parameter was passed in.
+  @retval EFI_OUT_OF_RESOURCES   Not enough resource to calculate hash.
+  @retval EFI_ABORTED            An error was encountered.
+  @retval EFI_COMPROMISED_DATA   The data was compromised.
+  @retval EFI_SUCCESS            Variable digest was successfully verified.
+
+**/
+EFI_STATUS
+VerifyVariableDigest (
+  IN  PROTECTED_VARIABLE_GLOBAL  *Global,
+  IN  PROTECTED_VARIABLE_INFO    *VarInfo,
+  IN  VARIABLE_DIGEST            *VarDig
+  );
+
+/**
+
+  Get the variable digest.
+
+  @param[in]      Global        Pointer to global configuration data.
+  @param[in]      VarInfo       Pointer to verified copy of protected variables.
+  @param[in,out]  DigestValue   Pointer to variable digest value.
+
+  @retval EFI_INVALID_PARAMETER  Invalid parameter was passed in.
+  @retval EFI_OUT_OF_RESOURCES   Not enough resource to calculate hash.
+  @retval EFI_ABORTED            An error was encountered.
+  @retval EFI_COMPROMISED_DATA   The data was compromised.
+  @retval EFI_SUCCESS            Variable digest was successfully verified.
+
+**/
+EFI_STATUS
+GetVariableDigest (
+  IN      PROTECTED_VARIABLE_GLOBAL  *Global,
+  IN      PROTECTED_VARIABLE_INFO    *VarInfo,
+  IN  OUT UINT8                      *DigestValue
+  );
+
+/**
+
+  Compare variable name and Guid
+
+  @param[in]  Name1      Name of first variable.
+  @param[in]  Name1Size  Size of first variable.
+  @param[in]  Name2      Name of second variable.
+  @param[in]  Name2Size  Size of second variable.
+  @param[in]  Guid1      Guid for first variable.
+  @param[in]  Guid2      Guid for second variable.
+
+  @retval 0         First name is identical to Second name.
+  @return others    First name is not identical to Second name.
+
+**/
+INTN
+CompareVariableNameAndGuid (
+  IN CONST CHAR16  *Name1,
+  IN UINTN         Name1Size,
+  IN CONST CHAR16  *Name2,
+  IN UINTN         Name2Size,
+  IN EFI_GUID      *Guid1,
+  IN EFI_GUID      *Guid2
+  );
+
+/**
+
+  Compare variable digest.
+
+  @param[in]  Variable1     Pointer to first variable digest.
+  @param[in]  Variable2     Pointer to second variable digest.
+
+  @retval 0         Variables are identical.
+  @return others    Variables are not identical.
+
+**/
+INTN
+CompareVariableDigestInfo (
+  IN  VARIABLE_DIGEST  *Variable1,
+  IN  VARIABLE_DIGEST  *Variable2
+  );
+
+/**
+
+  Move a node backward in the order controlled by SortMethod.
+
+  @param[in]  Node          Pointer to node to be moved.
+  @param[in]  SortMethod    Method used to compare node in list.
+
+**/
+VOID
+MoveNodeBackward (
+  IN  OUT VARIABLE_DIGEST  *Node,
+  IN  SORT_METHOD          SortMethod
+  );
+
+/**
+
+  Remove variable digest node.
+
+  @param[in,out]  Global        Pointer to global configuration data.
+  @param[in,out]  VarDig        Pointer to variable digest value.
+  @param[in]      FreeResource  Flag to indicate whether to free resource.
+
+**/
+VOID
+RemoveVariableDigestNode (
+  IN  OUT PROTECTED_VARIABLE_GLOBAL  *Global,
+  IN  OUT VARIABLE_DIGEST            *VarDig,
+  IN      BOOLEAN                    FreeResource
+  );
+
+/**
+
+  Insert variable digest node.
+
+  @param[in,out]  Global        Pointer to global configuration data.
+  @param[in]      VarDig        Pointer to variable digest value.
+  @param[in]      SortMethod    Method for sorting.
+
+**/
+VOID
+InsertVariableDigestNode (
+  IN  OUT PROTECTED_VARIABLE_GLOBAL  *Global,
+  IN      VARIABLE_DIGEST            *VarDig,
+  IN      SORT_METHOD                SortMethod
+  );
+
+/**
+
+  Create variable digest node.
+
+  @param[in]  VariableName      Name of variable.
+  @param[in]  VendorGuid        Guid of variable.
+  @param[in]  NameSize          Size of variable name.
+  @param[in]  DataSize          Size of variable data.
+  @param[in]  AuthVar           Authenticated variable flag.
+  @param[in]  Global            Pointer to global configuration data.
+
+  @retval Ptr   Pointer to variable digest
+
+**/
+VARIABLE_DIGEST *
+CreateVariableDigestNode (
+  IN CHAR16                     *VariableName,
+  IN EFI_GUID                   *VendorGuid,
+  IN UINT16                     NameSize,
+  IN UINT32                     DataSize,
+  IN BOOLEAN                    AuthVar,
+  IN PROTECTED_VARIABLE_GLOBAL  *Global
+  );
+
+/**
+
+  This function is used to enumerate the variables managed by current
+  ProtectedVariableLib.
+
+  If the VarInfo->StoreIndex is invalid (VAR_INDEX_INVALID), the first variable
+  with the smallest StoreIndex will be returned. Otherwise, the variable with
+  StoreIndex just after than the VarInfo->StoreIndex will be returned.
+
+  @param[in,out]      VarInfo     Pointer to structure containing variable information.
+
+  @retval EFI_SUCCESS               Found the specified variable.
+  @retval EFI_INVALID_PARAMETER     VarInfo is NULL.
+  @retval EFI_NOT_FOUND             The specified variable could not be found.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetNextInternal (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
+  );
+
+/**
+
+  Find the specified variable digest
+
+  @param[in]  Global        Pointer to global configuration data.
+  @param[in]  VarInfo       Pointer to variable data.
+  @param[in]  FindNext      Flag to continue looking for variable.
+
+**/
+VARIABLE_DIGEST *
+FindVariableInternal (
+  IN PROTECTED_VARIABLE_GLOBAL  *Global,
+  IN PROTECTED_VARIABLE_INFO    *VarInfo,
+  IN BOOLEAN                    FindNext
+  );
+
+/**
+
+  Synchronize the RPMC counters
+
+  @param[in]  Global      Pointer to global configuration data.
+  @param[in]  VarInfo     Pointer to variable data.
+  @param[in]  FindNext    Flag to continue looking for variable.
+
+  @retval EFI_SUCCESS     Successfully sync RPMC counters.
+  @return others          Failed to sync RPMC counters.
+
+**/
+EFI_STATUS
+SyncRpmcCounter (
+  VOID
+  );
+
+/**
+
+  Perform for protected variable integrity check.
+
+  If this initialization failed upon any error, the whole variable services
+  should not be used.  A system reset might be needed to re-construct NV
+  variable storage to be the default state.
+
+  @param[in]  ContextIn   Pointer to variable service context needed by
+                          protected variable.
+
+  @retval EFI_SUCCESS               Protected variable services are ready.
+  @retval EFI_INVALID_PARAMETER     If ContextIn == NULL or something missing or
+                                    mismatching in the content in ContextIn.
+  @retval EFI_COMPROMISED_DATA      If failed to check integrity of protected variables.
+  @retval EFI_OUT_OF_RESOURCES      Fail to allocate enough resource.
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+PerformVariableIntegrityCheck (
+  IN  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn
+  );
+
+extern EFI_TIME                       mDefaultTimeStamp;
+extern VARIABLE_IDENTIFIER            mUnprotectedVariables[UnprotectedVarIndexMax];
+extern PROTECTED_VARIABLE_CONTEXT_IN  mVariableContextIn;
+extern PROTECTED_VARIABLE_GLOBAL      mProtectedVariableGlobal;
+
+#endif
diff --git a/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableCommon.c b/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableCommon.c
new file mode 100644
index 000000000000..ed1a8e1ec545
--- /dev/null
+++ b/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableCommon.c
@@ -0,0 +1,2095 @@
+/** @file
+  The common protected variable operation routines.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Base.h>
+#include <Uefi.h>
+#include <PiPei.h>
+
+#include <Guid/VariableFormat.h>
+#include <Guid/VarErrorFlag.h>
+
+#include <Library/HobLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/HashApiLib.h>
+#include <Library/SortLib.h>
+
+#include "ProtectedVariableInternal.h"
+
+EFI_TIME             mDefaultTimeStamp       = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+VARIABLE_IDENTIFIER  mUnprotectedVariables[] = {
+  {
+    METADATA_HMAC_VARIABLE_NAME,
+    &METADATA_HMAC_VARIABLE_GUID,
+    VAR_ADDED & VAR_IN_DELETED_TRANSITION
+  },
+  {
+    METADATA_HMAC_VARIABLE_NAME,
+    &METADATA_HMAC_VARIABLE_GUID,
+    VAR_ADDED
+  },
+  {
+    VAR_ERROR_FLAG_NAME,
+    &gEdkiiVarErrorFlagGuid,
+    VAR_ADDED
+  },
+  {
+    (CHAR16 *)PcdGetPtr (PcdPlatformVariableName),
+    (EFI_GUID *)PcdGetPtr (PcdPlatformVariableGuid),
+    VAR_ADDED
+  }
+};
+
+/**
+  Print variable information.
+
+  @param[in]   Data8      Pointer to data.
+  @param[in]   DataSize   Size of data.
+
+**/
+VOID
+PrintVariableData (
+  IN UINT8  *Data8,
+  IN UINTN  DataSize
+  )
+{
+  UINTN  Index;
+
+  for (Index = 0; Index < DataSize; Index++) {
+    if (Index % 0x10 == 0) {
+      DEBUG ((DEBUG_INFO, "\n%08X:", Index));
+    }
+
+    DEBUG ((DEBUG_INFO, " %02X", *Data8++));
+  }
+
+  DEBUG ((DEBUG_INFO, "\n"));
+}
+
+/**
+
+  Retrieve the context and global configuration data structure from HOB.
+
+  Once protected NV variable storage is cached and verified in PEI phase,
+  all related information are stored in a HOB which can be used by PEI variable
+  service itself and passed to SMM along with the boot flow, which can avoid
+  many duplicate works, like generating HMAC key, verifying NV variable storage,
+  etc.
+
+  The HOB can be identified by gEdkiiProtectedVariableGlobalGuid.
+
+  @param[out]   Global      Pointer to global configuration data from PEI phase.
+
+  @retval EFI_SUCCESS     The HOB was found, and Context and Global are retrieved.
+  @retval EFI_NOT_FOUND   The HOB was not found.
+
+**/
+EFI_STATUS
+EFIAPI
+GetProtectedVariableGlobalFromHob (
+  OUT PROTECTED_VARIABLE_GLOBAL  **Global
+  )
+{
+  VOID                           *Data;
+  EFI_PEI_HOB_POINTERS           Hob;
+  EFI_HOB_MEMORY_ALLOCATION      *MemoryAllocationHob;
+  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn;
+  EFI_PHYSICAL_ADDRESS           OldStart;
+  VARIABLE_DIGEST                *VarDig;
+  EFI_HOB_GUID_TYPE              *GuidHob;
+  UINTN                          Index;
+
+  Hob.Raw = GetFirstGuidHob (&gEdkiiProtectedVariableGlobalGuid);
+  if (Hob.Raw != NULL) {
+    Data = GET_GUID_HOB_DATA (Hob);
+  } else {
+    //
+    // Search the global from allocated memory blob.
+    //
+    Data                = NULL;
+    MemoryAllocationHob = NULL;
+
+    Hob.Raw = GetFirstHob (EFI_HOB_TYPE_MEMORY_ALLOCATION);
+    while (Hob.Raw != NULL) {
+      MemoryAllocationHob = (EFI_HOB_MEMORY_ALLOCATION *)Hob.Raw;
+      if (CompareGuid (
+            &MemoryAllocationHob->AllocDescriptor.Name,
+            &gEdkiiProtectedVariableGlobalGuid
+            ))
+      {
+        Data = (VOID *)(UINTN)
+               MemoryAllocationHob->AllocDescriptor.MemoryBaseAddress;
+        break;
+      }
+
+      Hob.Raw = GET_NEXT_HOB (Hob);
+      Hob.Raw = GetNextHob (EFI_HOB_TYPE_MEMORY_ALLOCATION, Hob.Raw);
+    }
+  }
+
+  if (Data == NULL) {
+    return EFI_NOT_FOUND;
+  }
+
+  if (Global != NULL) {
+    GuidHob = GetFirstGuidHob (&gEdkiiProtectedVariableContextGuid);
+    if (GuidHob != NULL) {
+      ContextIn = (PROTECTED_VARIABLE_CONTEXT_IN *)GET_GUID_HOB_DATA (GuidHob);
+    } else {
+      ASSERT (GuidHob == NULL);
+    }
+
+    *Global = (PROTECTED_VARIABLE_GLOBAL *)((UINT8 *)Data);
+    //
+    // Fix pointers in the HOB (due to physical memory readiness)
+    //
+    if ((*Global)->GlobalSelf != (EFI_PHYSICAL_ADDRESS)(UINTN)(*Global)) {
+      OldStart             = (*Global)->GlobalSelf;
+      (*Global)->ContextIn = GET_ADRS (ContextIn);
+
+      //
+      // Mark Memory caching is available
+      //
+      (*Global)->Flags.CacheReady = TRUE;
+
+      //
+      // Re-allocate new minimum cache
+      //
+      (*Global)->VariableCache = GET_ADRS (Data)
+                                 + ((*Global)->VariableCache - OldStart);
+
+      (*Global)->DigestContext = GET_ADRS (((*Global) + 1));
+      for (Index = 0; Index < UnprotectedVarIndexMax; Index++) {
+        if ((*Global)->Unprotected[Index] != VAR_INDEX_INVALID) {
+          (*Global)->Unprotected[Index] = GET_ADRS (Data)
+                                          + ((*Global)->Unprotected[Index] - OldStart);
+        }
+      }
+
+      (*Global)->LastAccessedVariable = GET_ADRS (Data)
+                                        + ((*Global)->LastAccessedVariable - OldStart);
+
+      //
+      // Fix all linked-list pointers inside VARIABLE_SIGNATURE.
+      //
+      (*Global)->VariableDigests = GET_ADRS (Data)
+                                   + ((*Global)->VariableDigests - OldStart);
+      VarDig = VAR_DIG_PTR ((*Global)->VariableDigests);
+      while (VarDig != NULL) {
+        if (VarDig->Prev != 0) {
+          VarDig->Prev = GET_ADRS (Data) + (VarDig->Prev - OldStart);
+        }
+
+        if (VarDig->Next != 0) {
+          VarDig->Next = GET_ADRS (Data) + (VarDig->Next - OldStart);
+        }
+
+        VarDig = VAR_DIG_NEXT (VarDig);
+      }
+
+      (*Global)->GlobalSelf = (EFI_PHYSICAL_ADDRESS)(UINTN)(*Global);
+    }
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+
+  Derive HMAC key from given variable root key.
+
+  @param[in]  RootKey       Pointer to root key to derive from.
+  @param[in]  RootKeySize   Size of root key.
+  @param[out] HmacKey       Pointer to generated HMAC key.
+  @param[in]  HmacKeySize   Size of HMAC key.
+
+  @retval TRUE      The HMAC key is derived successfully.
+  @retval FALSE     Failed to generate HMAC key from given root key.
+
+**/
+BOOLEAN
+EFIAPI
+GenerateMetaDataHmacKey (
+  IN   CONST UINT8  *RootKey,
+  IN   UINTN        RootKeySize,
+  OUT  UINT8        *HmacKey,
+  IN   UINTN        HmacKeySize
+  )
+{
+  UINT8  Salt[AES_BLOCK_SIZE];
+
+  return HkdfSha256ExtractAndExpand (
+           RootKey,
+           RootKeySize,
+           Salt,
+           0,
+           (UINT8 *)METADATA_HMAC_KEY_NAME,
+           METADATA_HMAC_KEY_NAME_SIZE,
+           HmacKey,
+           HmacKeySize
+           );
+}
+
+/**
+
+  Return the size of variable MetaDataHmacVar.
+
+  @param[in] AuthFlag         Auth-variable indicator.
+
+  @retval size of variable MetaDataHmacVar.
+
+**/
+UINTN
+GetMetaDataHmacVarSize (
+  IN      BOOLEAN  AuthFlag
+  )
+{
+  UINTN  Size;
+
+  if (AuthFlag) {
+    Size = sizeof (AUTHENTICATED_VARIABLE_HEADER);
+  } else {
+    Size = sizeof (VARIABLE_HEADER);
+  }
+
+  Size += METADATA_HMAC_VARIABLE_NAME_SIZE;
+  Size += GET_PAD_SIZE (Size);
+  Size += METADATA_HMAC_SIZE;
+  Size += GET_PAD_SIZE (Size);
+
+  return Size;
+}
+
+/**
+
+  Digests the given variable data and updates HMAC context.
+
+  @param[in]      Context        Pointer to initialized HMAC context.
+  @param[in]      VarInfo        Pointer to variable data.
+  @param[in]      UpdateMethod   Function to run when updating variable digest.
+
+  @retval TRUE    HMAC context was updated successfully.
+  @retval FALSE   Failed to update HMAC context.
+
+**/
+STATIC
+BOOLEAN
+UpdateVariableDigestData (
+  IN  VOID                     *Context,
+  IN  PROTECTED_VARIABLE_INFO  *VarInfo,
+  IN  DIGEST_UPDATE            UpdateMethod
+  )
+{
+  VOID     *Buffer[12];
+  UINT32   BufferSize[12];
+  UINTN    Index;
+  BOOLEAN  Status;
+
+  //
+  // Empty variable is legal here (e.g. variable deletion case or write-init case).
+  //
+  if ((VarInfo == NULL) ||
+      (VarInfo->CipherData == NULL) ||
+      (VarInfo->CipherDataSize == 0))
+  {
+    return TRUE;
+  }
+
+  //
+  // HMAC (":" || VariableName)
+  //
+  Buffer[0]     = METADATA_HMAC_SEP;
+  BufferSize[0] = METADATA_HMAC_SEP_SIZE;
+
+  Buffer[1]     = VarInfo->Header.VariableName;
+  BufferSize[1] = (UINT32)VarInfo->Header.NameSize;
+
+  //
+  // HMAC (":" || VendorGuid || Attributes || DataSize)
+  //
+  Buffer[2]     = METADATA_HMAC_SEP;
+  BufferSize[2] = METADATA_HMAC_SEP_SIZE;
+
+  Buffer[3]     = VarInfo->Header.VendorGuid;
+  BufferSize[3] = sizeof (EFI_GUID);
+
+  Buffer[4]     = &VarInfo->Header.Attributes;
+  BufferSize[4] = sizeof (VarInfo->Header.Attributes);
+
+  Buffer[5]     = &VarInfo->CipherDataSize;
+  BufferSize[5] = sizeof (VarInfo->CipherDataSize);
+
+  //
+  // HMAC (":" || CipherData)
+  //
+  Buffer[6]     = METADATA_HMAC_SEP;
+  BufferSize[6] = METADATA_HMAC_SEP_SIZE;
+
+  Buffer[7]     = VarInfo->CipherData;
+  BufferSize[7] = VarInfo->CipherDataSize;
+
+  //
+  // HMAC (":" || PubKeyIndex || AuthMonotonicCount || TimeStamp)
+  //
+  Buffer[8]     = METADATA_HMAC_SEP;
+  BufferSize[8] = METADATA_HMAC_SEP_SIZE;
+
+  Buffer[9]     = &VarInfo->Header.PubKeyIndex;
+  BufferSize[9] = sizeof (VarInfo->Header.PubKeyIndex);
+
+  Buffer[10]     = &VarInfo->Header.MonotonicCount;
+  BufferSize[10] = sizeof (VarInfo->Header.MonotonicCount);
+
+  Buffer[11] = (VarInfo->Header.TimeStamp != NULL) ?
+               VarInfo->Header.TimeStamp : &mDefaultTimeStamp;
+  BufferSize[11] = sizeof (EFI_TIME);
+
+  for (Index = 0; Index < ARRAY_SIZE (Buffer); ++Index) {
+    Status = UpdateMethod (Context, Buffer[Index], BufferSize[Index]);
+    if (!Status) {
+      ASSERT (FALSE);
+      return FALSE;
+    }
+  }
+
+  return TRUE;
+}
+
+/**
+
+  Digests the given variable data and updates HMAC context.
+
+  @param[in]      Context   Pointer to initialized HMAC context.
+  @param[in]      VarInfo   Pointer to variable data.
+
+  @retval TRUE    HMAC context was updated successfully.
+  @retval FALSE   Failed to update HMAC context.
+
+**/
+BOOLEAN
+UpdateVariableMetadataHmac (
+  IN  VOID                     *Context,
+  IN  PROTECTED_VARIABLE_INFO  *VarInfo
+  )
+{
+  return UpdateVariableDigestData (Context, VarInfo, (DIGEST_UPDATE)HmacSha256Update);
+}
+
+/**
+
+  Get the variable digest.
+
+  @param[in]      Global        Pointer to global configuration data.
+  @param[in]      VarInfo       Pointer to verified copy of protected variables.
+  @param[in,out]  DigestValue   Pointer to variable digest value.
+
+  @retval EFI_INVALID_PARAMETER  Invalid parameter was passed in.
+  @retval EFI_OUT_OF_RESOURCES   Not enough resource to calculate hash.
+  @retval EFI_ABORTED            An error was encountered.
+  @retval EFI_COMPROMISED_DATA   The data was compromised.
+  @retval EFI_SUCCESS            Variable digest was successfully verified.
+
+**/
+EFI_STATUS
+GetVariableDigest (
+  IN      PROTECTED_VARIABLE_GLOBAL  *Global,
+  IN      PROTECTED_VARIABLE_INFO    *VarInfo,
+  IN  OUT UINT8                      *DigestValue
+  )
+{
+  EFI_STATUS  Status;
+  VOID        *Context;
+
+  if ((Global == NULL) || (VarInfo == NULL) || (DigestValue == NULL)) {
+    ASSERT (Global != NULL);
+    ASSERT (VarInfo != NULL);
+    ASSERT (DigestValue != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Context = GET_BUFR (Global->DigestContext);
+  if (!HashApiInit (Context)) {
+    ASSERT (Context != NULL);
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  if (VarInfo->CipherData == NULL) {
+    VarInfo->CipherData     = VarInfo->Header.Data;
+    VarInfo->CipherDataSize = (UINT32)VarInfo->Header.DataSize;
+  }
+
+  if (  !UpdateVariableDigestData (Context, VarInfo, (DIGEST_UPDATE)HashApiUpdate)
+     || !HashApiFinal (Context, DigestValue))
+  {
+    ASSERT (FALSE);
+    Status = EFI_ABORTED;
+  } else {
+    Status = EFI_SUCCESS;
+  }
+
+  return Status;
+}
+
+/**
+
+  Verify the variable digest.
+
+  @param[in]  Global      Pointer to global configuration data.
+  @param[in]  VarInfo     Pointer to verified copy of protected variables.
+  @param[in]  VarDig      Pointer to variable digest data.
+
+  @retval EFI_INVALID_PARAMETER  Invalid parameter was passed in.
+  @retval EFI_OUT_OF_RESOURCES   Not enough resource to calculate hash.
+  @retval EFI_ABORTED            An error was encountered.
+  @retval EFI_COMPROMISED_DATA   The data was compromised.
+  @retval EFI_SUCCESS            Variable digest was successfully verified.
+
+**/
+EFI_STATUS
+VerifyVariableDigest (
+  IN  PROTECTED_VARIABLE_GLOBAL  *Global,
+  IN  PROTECTED_VARIABLE_INFO    *VarInfo,
+  IN  VARIABLE_DIGEST            *VarDig
+  )
+{
+  EFI_STATUS  Status;
+  UINT8       NewDigest[METADATA_HMAC_SIZE];
+
+  if (Global->Flags.RecoveryMode || !VarDig->Flags.Protected) {
+    return EFI_SUCCESS;
+  }
+
+  ASSERT (VarDig->DigestSize == sizeof (NewDigest));
+
+  Status = GetVariableDigest (Global, VarInfo, NewDigest);
+  if (!EFI_ERROR (Status)) {
+    if (CompareMem (VAR_DIG_VALUE (VarDig), NewDigest, VarDig->DigestSize) != 0) {
+      Status = EFI_COMPROMISED_DATA;
+    }
+  }
+
+  return Status;
+}
+
+/**
+  Initialize variable MetaDataHmacVar.
+
+  @param[in,out]  Variable      Pointer to buffer of MetaDataHmacVar.
+  @param[in]      AuthFlag      Variable format flag.
+
+**/
+VOID
+InitMetadataHmacVariable (
+  IN  OUT VARIABLE_HEADER  *Variable,
+  IN      BOOLEAN          AuthFlag
+  )
+{
+  UINT8                          *NamePtr;
+  AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
+
+  Variable->StartId    = VARIABLE_DATA;
+  Variable->State      = VAR_ADDED;
+  Variable->Reserved   = 0;
+  Variable->Attributes = VARIABLE_ATTRIBUTE_NV_BS_RT;
+
+  if (AuthFlag) {
+    AuthVariable = (AUTHENTICATED_VARIABLE_HEADER *)Variable;
+
+    AuthVariable->NameSize       = METADATA_HMAC_VARIABLE_NAME_SIZE;
+    AuthVariable->DataSize       = METADATA_HMAC_SIZE;
+    AuthVariable->PubKeyIndex    = 0;
+    AuthVariable->MonotonicCount = 0;
+
+    ZeroMem (&AuthVariable->TimeStamp, sizeof (EFI_TIME));
+    CopyMem (&AuthVariable->VendorGuid, &METADATA_HMAC_VARIABLE_GUID, sizeof (EFI_GUID));
+
+    NamePtr = (UINT8 *)AuthVariable + sizeof (AUTHENTICATED_VARIABLE_HEADER);
+  } else {
+    Variable->NameSize = METADATA_HMAC_VARIABLE_NAME_SIZE;
+    Variable->DataSize = METADATA_HMAC_SIZE;
+
+    CopyMem (&Variable->VendorGuid, &METADATA_HMAC_VARIABLE_GUID, sizeof (EFI_GUID));
+
+    NamePtr = (UINT8 *)Variable + sizeof (VARIABLE_HEADER);
+  }
+
+  CopyMem (NamePtr, METADATA_HMAC_VARIABLE_NAME, METADATA_HMAC_VARIABLE_NAME_SIZE);
+}
+
+/**
+  Re-calculate HMAC based on new variable data and re-generate MetaDataHmacVar.
+
+  @param[in]      Global          Pointer to global configuration data.
+  @param[in]      NewVarInfo      Pointer to buffer of new variable data.
+  @param[in,out]  NewHmacVarInfo  Pointer to buffer of new MetaDataHmacVar.
+
+  @return EFI_SUCCESS           The HMAC value was updated successfully.
+  @return EFI_ABORTED           Failed to calculate the HMAC value.
+  @return EFI_OUT_OF_RESOURCES  Not enough resource to calculate HMC value.
+  @return EFI_NOT_FOUND         The MetaDataHmacVar was not found in storage.
+
+**/
+EFI_STATUS
+RefreshVariableMetadataHmac (
+  IN      PROTECTED_VARIABLE_GLOBAL  *Global,
+  IN      PROTECTED_VARIABLE_INFO    *NewVarInfo,
+  IN  OUT PROTECTED_VARIABLE_INFO    *NewHmacVarInfo
+  )
+{
+  EFI_STATUS                     Status;
+  VOID                           *Context;
+  UINT32                         Counter;
+  PROTECTED_VARIABLE_INFO        VarInfo;
+  PROTECTED_VARIABLE_INFO        CurrHmacVarInfo;
+  UINT8                          *HmacValue;
+  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn;
+  VARIABLE_DIGEST                *VarDig;
+  VARIABLE_DIGEST                *HmacVarDig;
+
+  ZeroMem ((VOID *)&VarInfo, sizeof (VarInfo));
+  ZeroMem ((VOID *)&CurrHmacVarInfo, sizeof (CurrHmacVarInfo));
+
+  Status = RequestMonotonicCounter (RPMC_COUNTER_2, &Counter);
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
+  Counter  += 1;
+  ContextIn = GET_CNTX (Global);
+
+  //
+  // Delete current MetaDataHmacVariable first, if any.
+  //
+  if (Global->Unprotected[IndexHmacAdded] != VAR_INDEX_INVALID) {
+    HmacVarDig = VAR_DIG_PTR (Global->Unprotected[IndexHmacAdded]);
+
+    CurrHmacVarInfo.Header.NameSize     = HmacVarDig->NameSize;
+    CurrHmacVarInfo.Header.VariableName = VAR_DIG_NAME (HmacVarDig);
+    CurrHmacVarInfo.Header.VendorGuid   = VAR_DIG_GUID (HmacVarDig);
+
+    CurrHmacVarInfo.Buffer     = VAR_HDR_PTR (HmacVarDig->CacheIndex);
+    CurrHmacVarInfo.StoreIndex = HmacVarDig->StoreIndex;
+    CurrHmacVarInfo.Flags.Auth = HmacVarDig->Flags.Auth;
+    //
+    // Force marking current MetaDataHmacVariable as VAR_IN_DELETED_TRANSITION.
+    //
+    CurrHmacVarInfo.Buffer->State &= VAR_IN_DELETED_TRANSITION;
+    HmacVarDig->State             &= VAR_IN_DELETED_TRANSITION;
+    Status                         = ContextIn->UpdateVariableStore (
+                                                  &CurrHmacVarInfo,
+                                                  OFFSET_OF (VARIABLE_HEADER, State),
+                                                  sizeof (CurrHmacVarInfo.Buffer->State),
+                                                  &CurrHmacVarInfo.Buffer->State
+                                                  );
+    if (EFI_ERROR (Status)) {
+      ASSERT_EFI_ERROR (Status);
+      return Status;
+    }
+  } else if (Global->Unprotected[IndexHmacInDel] != VAR_INDEX_INVALID) {
+    HmacVarDig = VAR_DIG_PTR (Global->Unprotected[IndexHmacInDel]);
+  } else {
+    //
+    // No MetaDataHmacVar. Allocate space to cache its value.
+    //
+    HmacVarDig = CreateVariableDigestNode (
+                   METADATA_HMAC_VARIABLE_NAME,
+                   &METADATA_HMAC_VARIABLE_GUID,
+                   METADATA_HMAC_VARIABLE_NAME_SIZE,
+                   METADATA_HMAC_SIZE,
+                   Global->Flags.Auth,
+                   Global
+                   );
+    if (HmacVarDig == NULL) {
+      ASSERT (HmacVarDig != NULL);
+      return EFI_OUT_OF_RESOURCES;
+    }
+
+    HmacVarDig->Flags.Protected = FALSE;
+  }
+
+  if (HmacVarDig->CacheIndex == VAR_INDEX_INVALID) {
+    HmacVarDig->CacheIndex = (GET_ADRS (Global)) + (Global->StructSize - GetMetaDataHmacVarSize (Global->Flags.Auth));
+  }
+
+  //
+  // Construct new MetaDataHmacVar.
+  //
+  if (NewHmacVarInfo == NULL) {
+    NewHmacVarInfo         = &VarInfo;
+    NewHmacVarInfo->Buffer = GET_BUFR (HmacVarDig->CacheIndex);
+  }
+
+  InitMetadataHmacVariable (NewHmacVarInfo->Buffer, Global->Flags.Auth);
+
+  NewHmacVarInfo->StoreIndex = VAR_INDEX_INVALID;     // Skip calculating offset
+  NewHmacVarInfo->Flags.Auth = Global->Flags.Auth;
+  Status                     = ContextIn->GetVariableInfo (NewHmacVarInfo);
+  ASSERT_EFI_ERROR (Status);
+  HmacValue = NewHmacVarInfo->Header.Data;
+
+  //
+  // Re-calculate HMAC for all valid variables
+  //
+  Context = HmacSha256New ();
+  if (Context == NULL) {
+    ASSERT (Context != NULL);
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  Status = EFI_ABORTED;
+  if (!HmacSha256SetKey (
+         Context,
+         Global->MetaDataHmacKey,
+         sizeof (Global->MetaDataHmacKey)
+         ))
+  {
+    ASSERT (FALSE);
+    goto Done;
+  }
+
+  //
+  // HMAC (|| hash(Var1) || hash(Var2) || ... || hash(VarN))
+  //
+  VarDig = VAR_DIG_PTR (Global->VariableDigests);
+  while (VarDig != NULL) {
+    if (VarDig->Flags.Valid && VarDig->Flags.Protected) {
+      HmacSha256Update (Context, VAR_DIG_VALUE (VarDig), VarDig->DigestSize);
+    }
+
+    VarDig = VAR_DIG_NEXT (VarDig);
+  }
+
+  //
+  // HMAC (RpmcMonotonicCounter)
+  //
+  if (!HmacSha256Update (Context, &Counter, sizeof (Counter))) {
+    ASSERT (FALSE);
+    goto Done;
+  }
+
+  if (!HmacSha256Final (Context, HmacValue)) {
+    ASSERT (FALSE);
+    goto Done;
+  }
+
+  //
+  // Update HMAC value in cache.
+  //
+  CopyMem (VAR_DIG_VALUE (HmacVarDig), HmacValue, HmacVarDig->DataSize);
+  if ((HmacVarDig->Prev == 0) && (HmacVarDig->Next == 0)) {
+    InsertVariableDigestNode (Global, HmacVarDig, NULL);
+  }
+
+  //
+  // Just one MetaDataHmacVar is needed for normal operation.
+  //
+  Global->Unprotected[IndexHmacAdded] = VAR_DIG_ADR (HmacVarDig);
+  Global->Unprotected[IndexHmacInDel] = VAR_INDEX_INVALID;
+
+  Status = EFI_SUCCESS;
+
+Done:
+  if (Context != NULL) {
+    HmacSha256Free (Context);
+  }
+
+  return Status;
+}
+
+/**
+
+  Check if a given variable is unprotected variable specified in advance
+  and return its index ID.
+
+  @param[in] Global     Pointer to global configuration data.
+  @param[in] VarInfo    Pointer to variable information data.
+
+  @retval IndexHmacInDel    Variable is MetaDataHmacVar in delete-transition state.
+  @retval IndexHmacAdded    Variable is MetaDataHmacVar in valid state.
+  @retval IndexErrorFlag    Variable is VarErrorLog.
+  @retval Others            Variable is not any known unprotected variables.
+
+**/
+UNPROTECTED_VARIABLE_INDEX
+CheckKnownUnprotectedVariable (
+  IN  PROTECTED_VARIABLE_GLOBAL  *Global,
+  IN  PROTECTED_VARIABLE_INFO    *VarInfo
+  )
+{
+  UNPROTECTED_VARIABLE_INDEX  Index;
+
+  if ((VarInfo == NULL) || (  (VarInfo->StoreIndex == VAR_INDEX_INVALID)
+                           && (  (VarInfo->Header.VariableName == NULL)
+                              || (VarInfo->Header.VendorGuid == NULL))))
+  {
+    ASSERT (VarInfo != NULL);
+    ASSERT (VarInfo->StoreIndex != VAR_INDEX_INVALID);
+    ASSERT (VarInfo->Header.VariableName != NULL);
+    ASSERT (VarInfo->Header.VendorGuid != NULL);
+    return UnprotectedVarIndexMax;
+  }
+
+  for (Index = 0; Index < UnprotectedVarIndexMax; ++Index) {
+    if (  (Global->Unprotected[Index] != VAR_INDEX_INVALID)
+       && (VarInfo->StoreIndex != VAR_INDEX_INVALID))
+    {
+      if (VarInfo->StoreIndex == VAR_DIG_PTR (Global->Unprotected[Index])->StoreIndex) {
+        break;
+      }
+    } else if (IS_VARIABLE (
+                 &VarInfo->Header,
+                 mUnprotectedVariables[Index].VariableName,
+                 mUnprotectedVariables[Index].VendorGuid
+                 ) && (VarInfo->Header.State == mUnprotectedVariables[Index].State))
+    {
+      break;
+    }
+  }
+
+  return Index;
+}
+
+/**
+
+  Compare variable name and Guid
+
+  @param[in]  Name1      Name of first variable.
+  @param[in]  Name1Size  Size of first variable.
+  @param[in]  Name2      Name of second variable.
+  @param[in]  Name2Size  Size of second variable.
+  @param[in]  Guid1      Guid for first variable.
+  @param[in]  Guid2      Guid for second variable.
+
+  @retval 0         First name is identical to Second name.
+  @return others    First name is not identical to Second name.
+
+**/
+INTN
+CompareVariableNameAndGuid (
+  IN CONST CHAR16  *Name1,
+  IN UINTN         Name1Size,
+  IN CONST CHAR16  *Name2,
+  IN UINTN         Name2Size,
+  IN EFI_GUID      *Guid1,
+  IN EFI_GUID      *Guid2
+  )
+{
+  INTN  Result;
+
+  Result = StrnCmp (
+             Name1,
+             Name2,
+             MIN (Name1Size, Name2Size) / sizeof (CHAR16)
+             );
+  if (Result == 0) {
+    if (Name1Size != Name2Size) {
+      //
+      // Longer name is 'bigger' than shorter one.
+      //
+      Result = (INTN)Name1Size - (INTN)Name2Size;
+    } else {
+      //
+      // The variable name is the same. Compare the GUID.
+      //
+      Result = CompareMem ((VOID *)Guid1, (VOID *)Guid2, sizeof (EFI_GUID));
+    }
+  }
+
+  return Result;
+}
+
+/**
+
+  Compare variable digest.
+
+  @param[in]  Variable1     Pointer to first variable digest.
+  @param[in]  Variable2     Pointer to second variable digest.
+
+  @retval 0         Variables are identical.
+  @return others    Variables are not identical.
+
+**/
+INTN
+CompareVariableDigestInfo (
+  IN  VARIABLE_DIGEST  *Variable1,
+  IN  VARIABLE_DIGEST  *Variable2
+  )
+{
+  return CompareVariableNameAndGuid (
+           VAR_DIG_NAME (Variable1),
+           Variable1->NameSize,
+           VAR_DIG_NAME (Variable2),
+           Variable2->NameSize,
+           &Variable1->VendorGuid,
+           &Variable2->VendorGuid
+           );
+}
+
+/**
+
+  Move a node backward in the order controlled by SortMethod.
+
+  @param[in,out]  Node          Pointer to node to be moved.
+  @param[in]      SortMethod    Method used to compare node in list.
+
+**/
+VOID
+MoveNodeBackward (
+  IN  OUT VARIABLE_DIGEST  *Node,
+  IN      SORT_METHOD      SortMethod
+  )
+{
+  VARIABLE_DIGEST  *Curr;
+  VARIABLE_DIGEST  *Prev;
+  INTN             Result;
+
+  Curr = Node;
+  while (Curr != NULL) {
+    Prev = VAR_DIG_PREV (Curr);
+    if (Prev == NULL) {
+      Result = -1;
+    } else {
+      Result = SortMethod (Prev, Node);
+    }
+
+    //
+    // 'Result > 0' means the 'Prev' is 'bigger' than 'Node'. Continue to check
+    // previous node til a node 'smaller' than 'Node' found.
+    //
+    if (Result > 0) {
+      Curr = Prev;
+      continue;
+    }
+
+    if (Curr != Node) {
+      //
+      // Remove Node first
+      //
+      if (VAR_DIG_PREV (Node) != NULL) {
+        VAR_DIG_PREV (Node)->Next = Node->Next;
+      }
+
+      if (VAR_DIG_NEXT (Node) != NULL) {
+        VAR_DIG_NEXT (Node)->Prev = Node->Prev;
+      }
+
+      //
+      // Insert Node before Curr.
+      //
+      Node->Prev = Curr->Prev;
+      Node->Next = VAR_DIG_ADR (Curr);
+
+      if (Curr->Prev != 0) {
+        VAR_DIG_PREV (Curr)->Next = VAR_DIG_ADR (Node);
+      }
+
+      Curr->Prev = VAR_DIG_ADR (Node);
+    }
+
+    //
+    // If there're two identical variables in storage, one of them must be
+    // "in-delete-transition" state. Mark it as "deleted" anyway.
+    //
+    if (Result == 0) {
+      if (Curr->State == (VAR_ADDED & VAR_IN_DELETED_TRANSITION)) {
+        Curr->State &= VAR_DELETED;
+      }
+
+      if (Prev->State == (VAR_ADDED & VAR_IN_DELETED_TRANSITION)) {
+        Prev->State &= VAR_DELETED;
+      }
+    }
+
+    break;
+  }
+}
+
+/**
+
+  Create variable digest node.
+
+  @param[in]  VariableName      Name of variable.
+  @param[in]  VendorGuid        Guid of variable.
+  @param[in]  NameSize          Size of variable name.
+  @param[in]  DataSize          Size of variable data.
+  @param[in]  AuthVar           Authenticated variable flag.
+  @param[in]  Global            Pointer to global configuration data.
+
+  @retval Ptr   Pointer to variable digest
+
+**/
+VARIABLE_DIGEST *
+CreateVariableDigestNode (
+  IN CHAR16                     *VariableName,
+  IN EFI_GUID                   *VendorGuid,
+  IN UINT16                     NameSize,
+  IN UINT32                     DataSize,
+  IN BOOLEAN                    AuthVar,
+  IN PROTECTED_VARIABLE_GLOBAL  *Global
+  )
+{
+  VARIABLE_DIGEST  *VarDig;
+  VOID             *Buffer;
+  UINTN            VarSize;
+
+  VarDig = (VARIABLE_DIGEST *)AllocateZeroPool (
+                                sizeof (VARIABLE_DIGEST) + NameSize + METADATA_HMAC_SIZE
+                                );
+  if ((VarDig == NULL) || (Global == NULL)) {
+    ASSERT (VarDig != NULL);
+    ASSERT (Global != NULL);
+    return NULL;
+  }
+
+  VarDig->DataSize        = DataSize;
+  VarDig->NameSize        = NameSize;
+  VarDig->DigestSize      = METADATA_HMAC_SIZE;
+  VarDig->State           = VAR_ADDED;
+  VarDig->Attributes      = VARIABLE_ATTRIBUTE_NV_BS_RT;
+  VarDig->Flags.Auth      = AuthVar;
+  VarDig->Flags.Valid     = TRUE;
+  VarDig->Flags.Freeable  = TRUE;
+  VarDig->Flags.Protected = PcdGetBool (PcdProtectedVariableIntegrity);
+  VarDig->Flags.Encrypted = PcdGetBool (PcdProtectedVariableConfidentiality);
+  VarDig->StoreIndex      = VAR_INDEX_INVALID;
+  VarDig->CacheIndex      = VAR_INDEX_INVALID;
+
+  if (Global->Flags.CacheReady == TRUE) {
+    VarSize  =  VARIABLE_HEADER_SIZE (VarDig->Flags.Auth);
+    VarSize += VarDig->NameSize + GET_PAD_SIZE (VarDig->NameSize);
+    VarSize += VarDig->DataSize + GET_PAD_SIZE (VarDig->DataSize);
+    VarSize  = HEADER_ALIGN (VarSize);
+
+    Buffer = AllocateZeroPool (VarSize);
+    if (Buffer != NULL) {
+      VarDig->CacheIndex = (EFI_PHYSICAL_ADDRESS)(UINTN)Buffer;
+    }
+  }
+
+  CopyMem (VAR_DIG_NAME (VarDig), VariableName, NameSize);
+  CopyMem (VAR_DIG_GUID (VarDig), VendorGuid, sizeof (EFI_GUID));
+
+  return VarDig;
+}
+
+/**
+
+  Remove variable digest node.
+
+  @param[in,out]  Global        Pointer to global configuration data.
+  @param[in,out]  VarDig        Pointer to variable digest value.
+  @param[in]      FreeResource  Flag to indicate whether to free resource.
+
+**/
+VOID
+RemoveVariableDigestNode (
+  IN  OUT PROTECTED_VARIABLE_GLOBAL  *Global,
+  IN  OUT VARIABLE_DIGEST            *VarDig,
+  IN      BOOLEAN                    FreeResource
+  )
+{
+  VARIABLE_DIGEST  *Prev;
+  VARIABLE_DIGEST  *Next;
+
+  Prev = VAR_DIG_PREV (VarDig);
+  Next = VAR_DIG_NEXT (VarDig);
+
+  if (Global->VariableDigests == VAR_DIG_ADR (VarDig)) {
+    Global->VariableDigests = VAR_DIG_ADR (Next);
+  }
+
+  if (Prev != NULL) {
+    Prev->Next = VAR_DIG_ADR (Next);
+  }
+
+  if (Next != NULL) {
+    Next->Prev = VAR_DIG_ADR (Prev);
+  }
+
+  VarDig->Prev        = 0;
+  VarDig->Next        = 0;
+  VarDig->Flags.Valid = FALSE;
+
+  if (FreeResource && VarDig->Flags.Freeable) {
+    if ((VarDig->CacheIndex != 0) && (VarDig->CacheIndex != VAR_INDEX_INVALID)) {
+      VarDig->CacheIndex = VAR_INDEX_INVALID;
+    }
+  }
+}
+
+/**
+
+  Insert variable digest node.
+
+  @param[in,out]  Global        Pointer to global configuration data.
+  @param[in]      VarDig        Pointer to variable digest value.
+  @param[in]      SortMethod    Method for sorting.
+
+**/
+VOID
+InsertVariableDigestNode (
+  IN  OUT PROTECTED_VARIABLE_GLOBAL  *Global,
+  IN      VARIABLE_DIGEST            *VarDig,
+  IN      SORT_METHOD                SortMethod
+  )
+{
+  VARIABLE_DIGEST  *Curr;
+  VARIABLE_DIGEST  *Prev;
+  BOOLEAN          DoReplace;
+  INTN             Result;
+
+  if (SortMethod == NULL) {
+    SortMethod = CompareVariableDigestInfo;
+  }
+
+  DoReplace = FALSE;
+  Curr      = VAR_DIG_PTR (Global->VariableDigests);
+  if (Curr == NULL) {
+    //
+    // First one.
+    //
+    VarDig->Prev            = 0;
+    VarDig->Next            = 0;
+    Global->VariableDigests = VAR_DIG_ADR (VarDig);
+    return;
+  }
+
+  while (Curr != NULL && Curr != VarDig) {
+    Result = SortMethod (VarDig, Curr);
+
+    if (Result <= 0) {
+      ASSERT (VarDig->StoreIndex != Curr->StoreIndex);
+
+      //
+      // The same variable already in list?
+      //
+      if (Result == 0) {
+        //
+        // Keep only the same new one, unless states are different. In such
+        // situation, the one with no VAR_ADDED will be deleted.
+        //
+        if (VarDig->State >= Curr->State) {
+          DoReplace         = TRUE;
+          Curr->Flags.Valid = FALSE;    // to-be-deleted
+        } else {
+          DoReplace           = FALSE;
+          VarDig->Flags.Valid = FALSE;  // to-be-deleted
+        }
+      }
+
+      //
+      // Put VarDig before Curr
+      //
+      VarDig->Next = VAR_DIG_ADR (Curr);
+      VarDig->Prev = Curr->Prev;
+
+      if (VAR_DIG_PREV (Curr) != NULL) {
+        VAR_DIG_PREV (Curr)->Next = VAR_DIG_ADR (VarDig);
+      }
+
+      Curr->Prev = VAR_DIG_ADR (VarDig);
+
+      if (DoReplace) {
+        RemoveVariableDigestNode (Global, Curr, TRUE);
+      }
+
+      break;
+    }
+
+    Prev = Curr;
+    Curr = VAR_DIG_NEXT (Curr);
+    if (Curr == NULL) {
+      Prev->Next = VAR_DIG_ADR (VarDig);
+
+      VarDig->Prev = VAR_DIG_ADR (Prev);
+      VarDig->Next = 0;
+    }
+  }
+
+  //
+  // Update the head node if necessary.
+  //
+  if (VAR_DIG_PTR (VarDig->Prev) == NULL) {
+    Global->VariableDigests = VAR_DIG_ADR (VarDig);
+  }
+}
+
+/**
+
+  Find the specified variable digest
+
+  @param[in]  Global        Pointer to global configuration data.
+  @param[in]  VarInfo       Pointer to variable data.
+  @param[in]  FindNext      Flag to continue looking for variable.
+
+**/
+VARIABLE_DIGEST *
+FindVariableInternal (
+  IN PROTECTED_VARIABLE_GLOBAL  *Global,
+  IN PROTECTED_VARIABLE_INFO    *VarInfo,
+  IN BOOLEAN                    FindNext
+  )
+{
+  VARIABLE_DIGEST  *VarDig;
+  VARIABLE_DIGEST  *Found;
+  VARIABLE_DIGEST  *FirstStoreIndexVar;
+  BOOLEAN          ByIndex;
+  INTN             FwdOrBwd;
+
+  //
+  // If VarInfo->StoreIndex is valid, use it to find the variable. Otherwise,
+  // use the variable name and guid instead, if given. If no clue at all, return
+  // the variable with lowest StoreIndex.
+  //
+  if (  (VarInfo->StoreIndex != VAR_INDEX_INVALID)
+     || (VarInfo->Header.VariableName == NULL)
+     || (VarInfo->Header.VendorGuid == NULL))
+  {
+    ByIndex = TRUE;
+  } else {
+    ByIndex = FALSE;
+  }
+
+  Found              = NULL;
+  VarDig             = VAR_DIG_PTR (Global->VariableDigests);
+  FirstStoreIndexVar = VarDig;
+  FwdOrBwd           = 1;
+
+  //
+  // Discover variable with first/smallest store index
+  //
+  while (VarDig != NULL) {
+    if (VarDig->StoreIndex < FirstStoreIndexVar->StoreIndex) {
+      FirstStoreIndexVar = VAR_DIG_PTR (VarDig);
+    }
+
+    VarDig = VAR_DIG_NEXT (VarDig);
+  }
+
+  //
+  // Input variable is NULL than return first variable
+  // with smallest store index from the variable digest list.
+  //
+  if (((VarInfo->Header.VariableName == NULL) ||
+       (VarInfo->Header.VendorGuid == NULL)) &&
+      (ByIndex == FALSE))
+  {
+    return FirstStoreIndexVar;
+  }
+
+  //
+  // Start with first entry
+  //
+  VarDig = VAR_DIG_PTR (Global->VariableDigests);
+  while (VarDig != NULL) {
+    if (ByIndex) {
+      if (FindNext) {
+        if (VarDig->StoreIndex == VarInfo->StoreIndex) {
+          Found = VarDig = VAR_DIG_NEXT (VarDig);
+          break;
+        }
+      } else if (VarDig->StoreIndex == VarInfo->StoreIndex) {
+        Found = VarDig;
+        break;
+      }
+    } else {
+      //
+      // Match given variable name and vendor guid.
+      //
+      if (IS_VARIABLE (&VarInfo->Header, VAR_DIG_NAME (VarDig), VAR_DIG_GUID (VarDig))) {
+        Found = (FindNext) ? VAR_DIG_NEXT (VarDig) : VarDig;
+        break;
+      }
+    }
+
+    VarDig = (FwdOrBwd > 0) ? VAR_DIG_NEXT (VarDig) : VAR_DIG_PREV (VarDig);
+    if (VarDig == NULL) {
+    }
+  }
+
+  return Found;
+}
+
+/**
+
+  Synchronize the RPMC counters
+
+  @param[in]  Global      Pointer to global configuration data.
+  @param[in]  VarInfo     Pointer to variable data.
+  @param[in]  FindNext    Flag to continue looking for variable.
+
+  @retval EFI_SUCCESS     Successfully sync RPMC counters.
+  @return others          Failed to sync RPMC counters.
+
+**/
+EFI_STATUS
+SyncRpmcCounter (
+  VOID
+  )
+{
+  UINT32      Counter1;
+  UINT32      Counter2;
+  EFI_STATUS  Status;
+
+  //
+  // Sync RPMC1 & RPMC2.
+  //
+  Status = RequestMonotonicCounter (RPMC_COUNTER_1, &Counter1);
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
+  Status = RequestMonotonicCounter (RPMC_COUNTER_2, &Counter2);
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
+  while (Counter1 < Counter2) {
+    Status = IncrementMonotonicCounter (RPMC_COUNTER_1);
+    if (EFI_ERROR (Status)) {
+      ASSERT_EFI_ERROR (Status);
+      return Status;
+    }
+
+    ++Counter1;
+  }
+
+  while (Counter2 < Counter1) {
+    Status = IncrementMonotonicCounter (RPMC_COUNTER_2);
+    if (EFI_ERROR (Status)) {
+      ASSERT_EFI_ERROR (Status);
+      return Status;
+    }
+
+    ++Counter2;
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+
+  An alternative version of ProtectedVariableLibGetData to get plain data from
+  given variable, if encrypted.
+
+  @param[in]          Global        Pointer to global configuration data.
+  @param[in,out]      VarInfo       Pointer to structure containing variable
+                                    information. VarInfo->Header.Data must point
+                                    to the original variable data.
+
+  @retval EFI_SUCCESS               Found the specified variable.
+  @retval EFI_INVALID_PARAMETER     VarInfo is NULL or both VarInfo->Buffer and
+                                    VarInfo->Offset are invalid.
+  @retval EFI_NOT_FOUND             The specified variable could not be found.
+
+**/
+STATIC
+EFI_STATUS
+ProtectedVariableLibGetDataInternal (
+  IN      PROTECTED_VARIABLE_GLOBAL  *Global,
+  IN  OUT PROTECTED_VARIABLE_INFO    *VarInfo
+  )
+{
+  EFI_STATUS                     Status;
+  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn;
+  VOID                           *Buffer;
+  UINTN                          BufferSize;
+
+  if ((Global == NULL) || (VarInfo == NULL)) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  ContextIn = GET_CNTX (Global);
+
+  //
+  // Check if the data has been decrypted or not.
+  //
+  VarInfo->CipherData     = NULL;
+  VarInfo->CipherDataSize = 0;
+  VarInfo->PlainData      = NULL;
+  VarInfo->PlainDataSize  = 0;
+  Status                  = GetCipherDataInfo (VarInfo);
+
+  if ((Status == EFI_UNSUPPORTED) || (Status == EFI_NOT_FOUND)) {
+    VarInfo->Flags.DecryptInPlace = TRUE;
+    VarInfo->PlainDataSize        = (UINT32)VarInfo->Header.DataSize;
+    VarInfo->PlainData            = VarInfo->Header.Data;
+    VarInfo->CipherDataType       = 0;
+    VarInfo->CipherHeaderSize     = 0;
+    Status                        = EFI_SUCCESS;
+  } else if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
+  //
+  // If the variable data is cipher data, decrypt it inplace if possible.
+  //
+  if ((VarInfo->PlainData == NULL) && (VarInfo->CipherData != NULL)) {
+    VarInfo->Key     = Global->RootKey;
+    VarInfo->KeySize = sizeof (Global->RootKey);
+
+    switch (ContextIn->VariableServiceUser) {
+      case FromPeiModule:
+        VarInfo->Flags.DecryptInPlace = FALSE;
+        //
+        // In PEI VariableCache holds Cipher header + Cipher data
+        // Do not override Cipher header data during decrypt operation
+        //
+        VarInfo->PlainData = GET_BUFR (Global->VariableCache + VarInfo->CipherHeaderSize);
+
+        Status = DecryptVariable (VarInfo);
+        if (Status == EFI_UNSUPPORTED) {
+          VarInfo->PlainData        = VarInfo->Header.Data;
+          VarInfo->PlainDataSize    = (UINT32)VarInfo->Header.DataSize;
+          VarInfo->CipherDataType   = 0;
+          VarInfo->CipherHeaderSize = 0;
+
+          Status = EFI_SUCCESS;
+        }
+
+        break;
+
+      case FromSmmModule:
+        VarInfo->Flags.DecryptInPlace = FALSE;
+        VarInfo->PlainData            = GET_BUFR (Global->VariableCache);
+
+        Status = DecryptVariable (VarInfo);
+        if (Status == EFI_UNSUPPORTED) {
+          VarInfo->PlainData        = VarInfo->Header.Data;
+          VarInfo->PlainDataSize    = (UINT32)VarInfo->Header.DataSize;
+          VarInfo->CipherDataType   = 0;
+          VarInfo->CipherHeaderSize = 0;
+
+          Status = EFI_SUCCESS;
+        }
+
+        break;
+
+      case FromBootServiceModule:
+      case FromRuntimeModule:
+        //
+        // The SMM passes back only decrypted data. We re-use the original cipher
+        // data buffer to keep the plain data along with the cipher header.
+        //
+        VarInfo->Flags.DecryptInPlace = TRUE;
+        Buffer                        = (VOID *)((UINTN)VarInfo->CipherData + VarInfo->CipherHeaderSize);
+        BufferSize                    = VarInfo->PlainDataSize;
+        Status                        = ContextIn->FindVariableSmm (
+                                                     VarInfo->Header.VariableName,
+                                                     VarInfo->Header.VendorGuid,
+                                                     &VarInfo->Header.Attributes,
+                                                     &BufferSize,
+                                                     Buffer
+                                                     );
+        if (!EFI_ERROR (Status)) {
+          //
+          // Flag the payload as plain data to avoid re-decrypting.
+          //
+          VarInfo->CipherDataType = ENC_TYPE_NULL;
+          VarInfo->PlainDataSize  = (UINT32)BufferSize;
+          VarInfo->PlainData      = Buffer;
+
+          Status = SetCipherDataInfo (VarInfo);
+          if (Status == EFI_UNSUPPORTED) {
+            Status = EFI_SUCCESS;
+          }
+        }
+
+        break;
+
+      default:
+        Status = EFI_UNSUPPORTED;
+        break;
+    }
+
+    VarInfo->CipherData     = NULL;
+    VarInfo->CipherDataSize = 0;
+  }
+
+  return Status;
+}
+
+/**
+
+  An alternative version of ProtectedVariableLibGetData to get plain data, if
+  encrypted, from given variable, for different use cases.
+
+  @param[in,out]      VarInfo     Pointer to structure containing variable information.
+
+  @retval EFI_SUCCESS               Found the specified variable.
+  @retval EFI_INVALID_PARAMETER     VarInfo is NULL or both VarInfo->Buffer and
+                                    VarInfo->Offset are invalid.
+  @retval EFI_NOT_FOUND             The specified variable could not be found.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetByInfo (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
+  )
+{
+  EFI_STATUS                 Status;
+  PROTECTED_VARIABLE_GLOBAL  *Global;
+  VOID                       **Buffer;
+  UINT32                     BufferSize;
+
+  Status = GetProtectedVariableGlobal (&Global);
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
+  //
+  // Save the output data buffer because below call
+  // call will use this struct field internally.
+  //
+  Buffer     = VarInfo->PlainData;
+  BufferSize = VarInfo->PlainDataSize;
+
+  Status = ProtectedVariableLibGetDataInternal (Global, VarInfo);
+  if (EFI_ERROR (Status)) {
+    //
+    // Return with caller provided buffer with zero DataSize
+    //
+    VarInfo->PlainData     = Buffer;
+    VarInfo->PlainDataSize = 0;
+    return Status;
+  }
+
+  if ((Buffer == NULL) || ((BufferSize) < VarInfo->PlainDataSize)) {
+    //
+    // Return with caller provided buffer with true PlainDataSize
+    //
+    VarInfo->PlainData = Buffer;
+    return EFI_BUFFER_TOO_SMALL;
+  }
+
+  //
+  // Copy Plain data to ouput data buffer
+  //
+  CopyMem (Buffer, VarInfo->PlainData, VarInfo->PlainDataSize);
+  VarInfo->PlainData = Buffer;
+
+  return Status;
+}
+
+/**
+
+  Retrieve plain data, if encrypted, of given variable.
+
+  If variable encryption is employed, this function will initiate a SMM request
+  to get the plain data. Due to security consideration, the decryption can only
+  be done in SMM environment.
+
+  @param[in]      Variable           Pointer to header of a Variable.
+  @param[in,out]  Data               Pointer to plain data of the given variable.
+  @param[in,out]  DataSize           Size of data returned or data buffer needed.
+  @param[in]      AuthFlag           Auth-variable indicator.
+
+  @retval EFI_SUCCESS                Found the specified variable.
+  @retval EFI_INVALID_PARAMETER      Invalid parameter.
+  @retval EFI_NOT_FOUND              The specified variable could not be found.
+  @retval EFI_BUFFER_TOO_SMALL       If *DataSize is smaller than needed.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetByBuffer (
+  IN      VARIABLE_HEADER  *Variable,
+  IN  OUT VOID             *Data,
+  IN  OUT UINT32           *DataSize,
+  IN      BOOLEAN          AuthFlag
+  )
+{
+  EFI_STATUS                     Status;
+  PROTECTED_VARIABLE_INFO        VarInfo;
+  PROTECTED_VARIABLE_GLOBAL      *Global;
+  AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
+  VOID                           *Buffer;
+
+  if ((Variable == NULL) || (DataSize == NULL)) {
+    ASSERT (Variable != NULL);
+    ASSERT (DataSize != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Status = GetProtectedVariableGlobal (&Global);
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
+  ZeroMem (&VarInfo, sizeof (VarInfo));
+
+  VarInfo.Buffer     = Variable;
+  VarInfo.Flags.Auth = AuthFlag;
+
+  if (VarInfo.Flags.Auth == TRUE) {
+    AuthVariable = (AUTHENTICATED_VARIABLE_HEADER *)Variable;
+
+    VarInfo.Header.VariableName = (CHAR16 *)((UINTN)Variable + sizeof (AUTHENTICATED_VARIABLE_HEADER));
+    VarInfo.Header.NameSize     = AuthVariable->NameSize;
+    VarInfo.Header.VendorGuid   = &AuthVariable->VendorGuid;
+    VarInfo.Header.Attributes   = AuthVariable->Attributes;
+    VarInfo.Header.DataSize     = AuthVariable->DataSize;
+  } else {
+    VarInfo.Header.VariableName = (CHAR16 *)((UINTN)Variable + sizeof (VARIABLE_HEADER));
+    VarInfo.Header.NameSize     = Variable->NameSize;
+    VarInfo.Header.VendorGuid   = &Variable->VendorGuid;
+    VarInfo.Header.Attributes   = Variable->Attributes;
+    VarInfo.Header.DataSize     = Variable->DataSize;
+  }
+
+  Buffer              = VARIABLE_NAME (VarInfo.Buffer, VarInfo.Flags.Auth);
+  Buffer              = GET_BUFR (GET_ADRS (Buffer) + VarInfo.Header.NameSize);
+  Buffer              = GET_BUFR (GET_ADRS (Buffer) + GET_PAD_SIZE (VarInfo.Header.NameSize));
+  VarInfo.Header.Data = Buffer;
+
+  Status = ProtectedVariableLibGetDataInternal (Global, &VarInfo);
+  if (!EFI_ERROR (Status)) {
+    if ((*DataSize) < VarInfo.PlainDataSize) {
+      *DataSize = VarInfo.PlainDataSize;
+      return EFI_BUFFER_TOO_SMALL;
+    }
+
+    *DataSize = VarInfo.PlainDataSize;
+    CopyMem (Data, VarInfo.PlainData, VarInfo.PlainDataSize);
+  }
+
+  return Status;
+}
+
+/**
+  This service retrieves a variable's value using its name and GUID.
+
+  Read the specified variable from the UEFI variable store. If the Data
+  buffer is too small to hold the contents of the variable, the error
+  EFI_BUFFER_TOO_SMALL is returned and DataSize is set to the required buffer
+  size to obtain the data.
+
+  @param  VariableName          A pointer to a null-terminated string that is the variable's name.
+  @param  VariableGuid          A pointer to an EFI_GUID that is the variable's GUID. The combination of
+                                VariableGuid and VariableName must be unique.
+  @param  Attributes            If non-NULL, on return, points to the variable's attributes.
+  @param  DataSize              On entry, points to the size in bytes of the Data buffer.
+                                On return, points to the size of the data returned in Data.
+  @param  Data                  Points to the buffer which will hold the returned variable value.
+                                May be NULL with a zero DataSize in order to determine the size of the buffer needed.
+
+  @retval EFI_SUCCESS           The variable was read successfully.
+  @retval EFI_NOT_FOUND         The variable was be found.
+  @retval EFI_BUFFER_TOO_SMALL  The DataSize is too small for the resulting data.
+                                DataSize is updated with the size required for
+                                the specified variable.
+  @retval EFI_INVALID_PARAMETER VariableName, VariableGuid, DataSize or Data is NULL.
+  @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetByName (
+  IN      CONST  CHAR16    *VariableName,
+  IN      CONST  EFI_GUID  *VariableGuid,
+  OUT UINT32               *Attributes,
+  IN  OUT UINTN            *DataSize,
+  OUT VOID                 *Data OPTIONAL
+  )
+{
+  EFI_STATUS                     Status;
+  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn;
+  PROTECTED_VARIABLE_GLOBAL      *Global;
+  VARIABLE_DIGEST                *VarDig;
+  PROTECTED_VARIABLE_INFO        VarInfo;
+  EFI_TIME                       TimeStamp;
+  VOID                           *DataBuffer;
+
+  if ((VariableName == NULL) || (VariableGuid == NULL) || (DataSize == NULL)) {
+    ASSERT (VariableName != NULL);
+    ASSERT (VariableGuid != NULL);
+    ASSERT (DataSize != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Status = GetProtectedVariableGlobal (&Global);
+
+  if (EFI_ERROR (Status)) {
+    return EFI_UNSUPPORTED;
+  }
+
+  ContextIn = GET_CNTX (Global);
+
+  ZeroMem (&VarInfo, sizeof (VarInfo));
+  VarInfo.StoreIndex          = VAR_INDEX_INVALID;
+  VarInfo.Header.VariableName = (CHAR16 *)VariableName;
+  VarInfo.Header.NameSize     = StrSize (VariableName);
+  VarInfo.Header.VendorGuid   = (EFI_GUID *)VariableGuid;
+
+  VarDig = FindVariableInternal (Global, &VarInfo, FALSE);
+  if (VarDig == NULL) {
+    return EFI_NOT_FOUND;
+  }
+
+  if (Attributes != NULL) {
+    *Attributes = VarDig->Attributes;
+  }
+
+  if ((Data == NULL) || (*DataSize < VarDig->PlainDataSize)) {
+    *DataSize = VarDig->PlainDataSize;
+    return EFI_BUFFER_TOO_SMALL;
+  }
+
+  VarInfo.Flags.Auth      = VarDig->Flags.Auth;
+  VarInfo.Flags.Protected = VarDig->Flags.Protected;
+
+  //
+  // Verify digest before copy the data back, if the variable is not in cache.
+  //
+  if (VarDig->CacheIndex != VAR_INDEX_INVALID) {
+    VarInfo.Header.VariableName = NULL;
+    VarInfo.Header.VendorGuid   = NULL;
+    VarInfo.Buffer              = GET_BUFR (VarDig->CacheIndex);
+
+    Status = ContextIn->GetVariableInfo (&VarInfo);
+    ASSERT_EFI_ERROR (Status);
+  } else {
+    //
+    // A buffer for at least one variable data (<=PcdMax(Auth)VariableSize)
+    // must be reserved in advance.
+    //
+    ASSERT (
+      Global->VariableCache != 0
+           && Global->VariableCacheSize >= VarDig->DataSize
+      );
+    DataBuffer = GET_BUFR (Global->VariableCache);
+    //
+    // Note name and GUID are already there.
+    //
+    VarInfo.StoreIndex = VarDig->StoreIndex;
+
+    VarInfo.Header.VariableName = NULL; // Prevent name from being retrieved again.
+    VarInfo.Header.NameSize     = 0;
+    VarInfo.Header.VendorGuid   = NULL; // Prevent guid from being retrieved again.
+    VarInfo.Header.TimeStamp    = &TimeStamp;
+    VarInfo.Header.Data         = DataBuffer;
+    VarInfo.Header.DataSize     = VarDig->DataSize;
+
+    //
+    // Get detailed information about the variable.
+    //
+    Status = ContextIn->GetVariableInfo (&VarInfo);
+    ASSERT_EFI_ERROR (Status);
+
+    //
+    // The variable must be validated its digest value to avoid TOCTOU, if it's
+    // not been cached yet.
+    //
+    VarInfo.Header.VariableName = VAR_DIG_NAME (VarDig);
+    VarInfo.Header.NameSize     = VarDig->NameSize;
+    VarInfo.Header.VendorGuid   = &VarDig->VendorGuid;
+    Status                      = VerifyVariableDigest (Global, &VarInfo, VarDig);
+    if (EFI_ERROR (Status)) {
+      return Status;
+    }
+  }
+
+  //
+  // Decrypt the data, if necessary.
+  //
+  Status = ProtectedVariableLibGetDataInternal (Global, &VarInfo);
+  if (!EFI_ERROR (Status)) {
+    if (*DataSize < VarInfo.PlainDataSize) {
+      *DataSize = VarInfo.PlainDataSize;
+      return EFI_BUFFER_TOO_SMALL;
+    }
+
+    *DataSize = VarInfo.PlainDataSize;
+    CopyMem (Data, VarInfo.PlainData, VarInfo.PlainDataSize);
+  }
+
+  return Status;
+}
+
+/**
+
+  This function is used to enumerate the variables managed by current
+  ProtectedVariableLib.
+
+  If the VarInfo->StoreIndex is invalid (VAR_INDEX_INVALID), the first variable
+  with the smallest StoreIndex will be returned. Otherwise, the variable with
+  StoreIndex just after than the VarInfo->StoreIndex will be returned.
+
+  @param[in,out]      VarInfo     Pointer to structure containing variable information.
+
+  @retval EFI_SUCCESS               Found the specified variable.
+  @retval EFI_INVALID_PARAMETER     VarInfo is NULL.
+  @retval EFI_NOT_FOUND             The specified variable could not be found.
+
+**/
+STATIC
+EFI_STATUS
+GetNextVariableInternal (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
+  )
+{
+  EFI_STATUS                 Status;
+  PROTECTED_VARIABLE_GLOBAL  *Global;
+  VARIABLE_DIGEST            *Found;
+
+  if (VarInfo == NULL) {
+    ASSERT (VarInfo != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Status = GetProtectedVariableGlobal (&Global);
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
+  Found = FindVariableInternal (Global, VarInfo, TRUE);
+  if (Found == NULL) {
+    return EFI_NOT_FOUND;
+  }
+
+  //
+  // Return all cached data.
+  //
+  VarInfo->Header.VariableName = VAR_DIG_NAME (Found);
+  VarInfo->Header.VendorGuid   = VAR_DIG_GUID (Found);
+  VarInfo->Header.NameSize     = Found->NameSize;
+  VarInfo->Header.DataSize     = Found->DataSize;
+  VarInfo->Header.Attributes   = Found->Attributes;
+
+  VarInfo->PlainDataSize = Found->PlainDataSize;
+  VarInfo->StoreIndex    = Found->StoreIndex;
+  if (Found->CacheIndex != VAR_INDEX_INVALID) {
+    VarInfo->Buffer = GET_BUFR (Found->CacheIndex);
+  }
+
+  VarInfo->Flags.Auth = Found->Flags.Auth;
+
+  return EFI_SUCCESS;
+}
+
+/**
+
+  Find the request variable.
+
+  @param[in, out]  VarInfo      Pointer to variable data.
+
+  @retval EFI_SUCCESS           The variable was read successfully.
+  @retval EFI_NOT_FOUND         The variable could not be found.
+  @retval EFI_INVALID_PARAMETER Variable info is NULL.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibFind (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
+  )
+{
+  EFI_STATUS                 Status;
+  PROTECTED_VARIABLE_GLOBAL  *Global;
+  VARIABLE_DIGEST            *Found;
+
+  if (VarInfo == NULL) {
+    ASSERT (VarInfo != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Status = GetProtectedVariableGlobal (&Global);
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
+  Found = FindVariableInternal (Global, VarInfo, FALSE);
+  if (Found == NULL) {
+    return EFI_NOT_FOUND;
+  }
+
+  //
+  // Return all cached data.
+  //
+  VarInfo->Header.VariableName = VAR_DIG_NAME (Found);
+  VarInfo->Header.VendorGuid   = VAR_DIG_GUID (Found);
+  VarInfo->Header.NameSize     = Found->NameSize;
+  VarInfo->Header.DataSize     = Found->DataSize;
+  VarInfo->Header.Attributes   = Found->Attributes;
+
+  VarInfo->PlainDataSize = Found->PlainDataSize;
+  VarInfo->StoreIndex    = Found->StoreIndex;
+  if (Found->CacheIndex != VAR_INDEX_INVALID) {
+    VarInfo->Buffer = GET_BUFR (Found->CacheIndex);
+  }
+
+  VarInfo->Flags.Auth = Found->Flags.Auth;
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Return the next variable name and GUID.
+
+  This function is called multiple times to retrieve the VariableName
+  and VariableGuid of all variables currently available in the system.
+  On each call, the previous results are passed into the interface,
+  and, on return, the interface returns the data for the next
+  interface. When the entire variable list has been returned,
+  EFI_NOT_FOUND is returned.
+
+  @param  VariableNameSize  On entry, points to the size of the buffer pointed to by VariableName.
+                            On return, the size of the variable name buffer.
+  @param  VariableName      On entry, a pointer to a null-terminated string that is the variable's name.
+                            On return, points to the next variable's null-terminated name string.
+  @param  VariableGuid      On entry, a pointer to an EFI_GUID that is the variable's GUID.
+                            On return, a pointer to the next variable's GUID.
+
+  @retval EFI_SUCCESS           The variable was read successfully.
+  @retval EFI_NOT_FOUND         The variable could not be found.
+  @retval EFI_BUFFER_TOO_SMALL  The VariableNameSize is too small for the resulting
+                                data. VariableNameSize is updated with the size
+                                required for the specified variable.
+  @retval EFI_INVALID_PARAMETER VariableName, VariableGuid or
+                                VariableNameSize is NULL.
+  @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibFindNext (
+  IN OUT UINTN     *VariableNameSize,
+  IN OUT CHAR16    *VariableName,
+  IN OUT EFI_GUID  *VariableGuid
+  )
+{
+  EFI_STATUS                 Status;
+  PROTECTED_VARIABLE_INFO    VarInfo;
+  PROTECTED_VARIABLE_GLOBAL  *Global;
+  VARIABLE_DIGEST            *VarDig;
+  UINTN                      Size;
+
+  if ((VariableNameSize == NULL) || (VariableName == NULL) || (VariableGuid == NULL)) {
+    ASSERT (VariableNameSize != NULL);
+    ASSERT (VariableName != NULL);
+    ASSERT (VariableGuid != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Status = GetProtectedVariableGlobal (&Global);
+  if (EFI_ERROR (Status)) {
+    return Status;
+  }
+
+  SetMem (&VarInfo, sizeof (VarInfo), 0);
+  Size = StrSize (VariableName);
+
+  if (Size <= 2) {
+    VarDig = VAR_DIG_PTR (Global->VariableDigests);
+  } else {
+    VarInfo.Header.VariableName = VariableName;
+    VarInfo.Header.NameSize     = Size;
+    VarInfo.Header.VendorGuid   = VariableGuid;
+
+    VarInfo.StoreIndex = VAR_INDEX_INVALID;
+
+    VarDig = FindVariableInternal (Global, &VarInfo, TRUE);
+  }
+
+  if (VarDig == NULL) {
+    return EFI_NOT_FOUND;
+  }
+
+  if (VarDig->NameSize > *VariableNameSize) {
+    return EFI_BUFFER_TOO_SMALL;
+  }
+
+  CopyMem (VariableName, VAR_DIG_NAME (VarDig), VarDig->NameSize);
+  CopyGuid (VariableGuid, &VarDig->VendorGuid);
+  *VariableNameSize = VarInfo.Header.NameSize;
+
+  return EFI_SUCCESS;
+}
+
+/**
+
+  Return the next variable name and GUID.
+
+  @param[in, out]  VarInfo        Pointer to variable data.
+
+  @retval EFI_SUCCESS             The variable was read successfully.
+  @retval EFI_INVALID_PARAMETER   VarInfo is NULL.
+  @retval EFI_NOT_FOUND           The specified variable could not be found.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibFindNextEx (
+  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
+  )
+{
+  return GetNextVariableInternal (VarInfo);
+}
+
+/**
+
+  Return the max count of a variable.
+
+  @return   max count of a variable.
+
+**/
+UINTN
+ProtectedVariableLibGetMaxVariablesCount (
+  VOID
+  )
+{
+  PROTECTED_VARIABLE_GLOBAL  *Global;
+  PROTECTED_VARIABLE_INFO    VarInfo;
+  VARIABLE_DIGEST            *VarDig;
+  EFI_STATUS                 Status;
+  UINTN                      Count;
+
+  Status = GetProtectedVariableGlobal (&Global);
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return 0;
+  }
+
+  Count = 0;
+  ZeroMem (&VarInfo, sizeof (VarInfo));
+
+  //
+  // Start with first entry
+  //
+  VarDig                      = VAR_DIG_PTR (Global->VariableDigests);
+  VarInfo.Header.VariableName = VAR_DIG_NAME (VarDig);
+  VarInfo.Header.VendorGuid   = VAR_DIG_GUID (VarDig);
+  VarInfo.StoreIndex          = VarDig->StoreIndex;
+
+  do {
+    VarInfo.Buffer = NULL;
+    Status         = ProtectedVariableLibFindNextEx (&VarInfo);
+    if (EFI_ERROR (Status)) {
+      return Count;
+    }
+
+    Count++;
+  } while (TRUE);
+}
+
+/**
+  The function is called by PerformQuickSort to sort.
+
+  @param[in] Left            The pointer to first buffer.
+  @param[in] Right           The pointer to second buffer.
+
+  @retval 0                  Buffer1 equal to Buffer2.
+  @return < 0                Buffer1 is less than Buffer2.
+  @return > 0                Buffer1 is greater than Buffer2.
+
+**/
+INTN
+EFIAPI
+CompareStoreIndex (
+  IN CONST VOID  *Left,
+  IN CONST VOID  *Right
+  )
+{
+  EFI_PHYSICAL_ADDRESS  StoreIndex1;
+  EFI_PHYSICAL_ADDRESS  StoreIndex2;
+
+  StoreIndex1 = (*(EFI_PHYSICAL_ADDRESS *)Left);
+  StoreIndex2 = (*(EFI_PHYSICAL_ADDRESS *)Right);
+
+  if (StoreIndex1 == StoreIndex2) {
+    return (0);
+  }
+
+  if (StoreIndex1 < StoreIndex2) {
+    return (-1);
+  }
+
+  return (1);
+}
+
+/**
+  Refresh variable information changed by variable service.
+
+  @param Buffer           Pointer to a pointer of buffer.
+  @param NumElements      Pointer to number of elements in list.
+
+
+  @return EFI_SUCCESS     Successfully retrieved sorted list.
+  @return others          Unsuccessful.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibGetSortedList (
+  IN  OUT  EFI_PHYSICAL_ADDRESS  **Buffer,
+  IN  OUT  UINTN                 *NumElements
+  )
+{
+  EFI_STATUS                 Status;
+  UINTN                      Count;
+  UINTN                      StoreIndexTableSize;
+  EFI_PHYSICAL_ADDRESS       *StoreIndexTable;
+  PROTECTED_VARIABLE_INFO    VarInfo;
+  PROTECTED_VARIABLE_GLOBAL  *Global;
+  VARIABLE_DIGEST            *VarDig;
+
+  Status = GetProtectedVariableGlobal (&Global);
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
+  Count = 0;
+  ZeroMem (&VarInfo, sizeof (VarInfo));
+  StoreIndexTableSize = ProtectedVariableLibGetMaxVariablesCount ();
+  StoreIndexTable     = AllocateZeroPool (sizeof (EFI_PHYSICAL_ADDRESS) * StoreIndexTableSize);
+
+  //
+  // Start with first entry
+  //
+  VarDig                      = VAR_DIG_PTR (Global->VariableDigests);
+  VarInfo.Header.VariableName = VAR_DIG_NAME (VarDig);
+  VarInfo.Header.VendorGuid   = VAR_DIG_GUID (VarDig);
+  VarInfo.StoreIndex          = VarDig->StoreIndex;
+  StoreIndexTable[Count]      = VarInfo.StoreIndex;
+  Count++;
+
+  //
+  // Populate the un-sorted table
+  //
+  do {
+    VarInfo.Buffer = NULL;
+    Status         = ProtectedVariableLibFindNextEx (&VarInfo);
+    if (EFI_ERROR (Status)) {
+      break;
+    }
+
+    StoreIndexTable[Count] = VarInfo.StoreIndex;
+    Count++;
+  } while (TRUE);
+
+  PerformQuickSort (
+    StoreIndexTable,
+    Count,
+    sizeof (EFI_PHYSICAL_ADDRESS),
+    (SORT_COMPARE)CompareStoreIndex
+    );
+
+  *Buffer      = StoreIndexTable;
+  *NumElements = Count;
+
+  return EFI_SUCCESS;
+}
diff --git a/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableDxe.c b/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableDxe.c
new file mode 100644
index 000000000000..94df21eacf25
--- /dev/null
+++ b/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableDxe.c
@@ -0,0 +1,163 @@
+/** @file
+  Implemention of ProtectedVariableLib for SMM variable services.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <PiDxe.h>
+#include <Uefi.h>
+
+#include "Library/UefiBootServicesTableLib.h"
+#include "Library/MemoryAllocationLib.h"
+
+#include "ProtectedVariableInternal.h"
+
+PROTECTED_VARIABLE_CONTEXT_IN  mVariableContextIn = {
+  PROTECTED_VARIABLE_CONTEXT_IN_STRUCT_VERSION,
+  sizeof (PROTECTED_VARIABLE_CONTEXT_IN),
+  0,
+  FromSmmModule,
+  NULL,
+  NULL,
+  NULL,
+  NULL,
+  NULL
+};
+
+PROTECTED_VARIABLE_GLOBAL  mProtectedVariableGlobal = {
+  PROTECTED_VARIABLE_CONTEXT_OUT_STRUCT_VERSION,
+  sizeof (PROTECTED_VARIABLE_GLOBAL),
+  { 0 },
+  { 0 },
+  0,
+  0,
+  0,
+  0,
+  0,
+  0,
+  { 0,                                          0,  0 },
+  0,
+  0,
+  { 0,                                          0,  0, 0, 0, 0}
+};
+
+/**
+  Fix incorrect state of MetaDataHmacVariable before any variable update.
+
+  @param[in]   Event    The event that occurred
+  @param[in]   Context  For EFI compatibility.  Not used.
+
+**/
+VOID
+EFIAPI
+VariableWriteProtocolCallback (
+  IN  EFI_EVENT  Event,
+  IN  VOID       *Context
+  )
+{
+  EFI_STATUS  Status;
+
+  //
+  // Fix incorrect state of MetaDataHmacVariable before any variable update.
+  // This has to be done here due to the fact that this operation needs to
+  // update NV storage but the FVB and FTW protocol might not be ready during
+  // ProtectedVariableLibInitialize().
+  //
+  Status = FixupHmacVariable ();
+  ASSERT_EFI_ERROR (Status);
+
+  Status = ProtectedVariableLibWriteInit ();
+  ASSERT_EFI_ERROR (Status);
+
+  gBS->CloseEvent (Event);
+}
+
+/**
+
+  Initialization for protected variable services.
+
+  If this initialization failed upon any error, the whole variable services
+  should not be used.  A system reset might be needed to re-construct NV
+  variable storage to be the default state.
+
+  @param[in]  ContextIn   Pointer to variable service context needed by
+                          protected variable.
+
+  @retval EFI_SUCCESS               Protected variable services are ready.
+  @retval EFI_INVALID_PARAMETER     If ContextIn == NULL or something missing or
+                                    mismatching in the content in ContextIn.
+  @retval EFI_COMPROMISED_DATA      If failed to check integrity of protected variables.
+  @retval EFI_OUT_OF_RESOURCES      Fail to allocate enough resource.
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibInitialize (
+  IN  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn
+  )
+{
+  EFI_STATUS                     Status;
+  PROTECTED_VARIABLE_CONTEXT_IN  *ProtectedVarContext;
+  PROTECTED_VARIABLE_GLOBAL      *OldGlobal;
+  PROTECTED_VARIABLE_GLOBAL      *NewGlobal;
+  VOID                           *VarWriteReg;
+
+  if (  (ContextIn == NULL)
+     || (ContextIn->StructVersion != PROTECTED_VARIABLE_CONTEXT_IN_STRUCT_VERSION)
+     || (ContextIn->StructSize != sizeof (PROTECTED_VARIABLE_CONTEXT_IN))
+     || (ContextIn->GetVariableInfo == NULL)
+     || (ContextIn->GetNextVariableInfo == NULL)
+     || (ContextIn->UpdateVariableStore == NULL)
+     || (ContextIn->UpdateVariable == NULL))
+  {
+    ASSERT (ContextIn != NULL);
+    ASSERT (ContextIn->StructVersion == PROTECTED_VARIABLE_CONTEXT_IN_STRUCT_VERSION);
+    ASSERT (ContextIn->StructSize == sizeof (PROTECTED_VARIABLE_CONTEXT_IN));
+    ASSERT (ContextIn->GetVariableInfo != NULL);
+    ASSERT (ContextIn->GetNextVariableInfo != NULL);
+    ASSERT (ContextIn->UpdateVariableStore != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  GetProtectedVariableGlobal (&NewGlobal);
+  ProtectedVarContext = GET_CNTX (NewGlobal);
+  CopyMem (ProtectedVarContext, ContextIn, sizeof (mVariableContextIn));
+  ProtectedVarContext->VariableServiceUser = FromSmmModule;
+
+  //
+  // Get root key and HMAC key from HOB created by PEI variable driver.
+  //
+  Status = GetProtectedVariableGlobalFromHob (&OldGlobal);
+  ASSERT_EFI_ERROR (Status);
+
+  CopyMem ((VOID *)NewGlobal, (CONST VOID *)OldGlobal, sizeof (*OldGlobal));
+
+  //
+  // The keys must not be available outside SMM.
+  //
+  if (ProtectedVarContext->VariableServiceUser == FromSmmModule) {
+    ZeroMem (OldGlobal->RootKey, sizeof (OldGlobal->RootKey));
+    ZeroMem (OldGlobal->MetaDataHmacKey, sizeof (OldGlobal->MetaDataHmacKey));
+  }
+
+  //
+  // Register variable write protocol notify function used to fix any
+  // inconsistency in MetaDataHmacVariable before the first variable write
+  // operation.
+  //
+  NewGlobal->Flags.WriteInit  = FALSE;
+  NewGlobal->Flags.WriteReady = FALSE;
+
+  EfiCreateProtocolNotifyEvent (
+    &gEfiVariableWriteArchProtocolGuid,
+    TPL_CALLBACK,
+    VariableWriteProtocolCallback,
+    NULL,
+    &VarWriteReg
+    );
+
+  return EFI_SUCCESS;
+}
diff --git a/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariablePei.c b/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariablePei.c
new file mode 100644
index 000000000000..91d71a1e8525
--- /dev/null
+++ b/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariablePei.c
@@ -0,0 +1,1331 @@
+/** @file
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Base.h>
+#include <Uefi.h>
+#include <PiPei.h>
+
+#include <Guid/VariableFormat.h>
+#include <Ppi/MemoryDiscovered.h>
+
+#include <Library/HobLib.h>
+#include <Library/PeiServicesLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/ReportStatusCodeLib.h>
+
+#include "ProtectedVariableInternal.h"
+
+/**
+  Function allocates a global buffer.
+
+  This function allocates a buffer with the specified size.
+
+  @param[in] Size           Size of buffer to allocate.
+  @param[in] AllocatePage   Whether to allocate pages.
+
+  @retval Buffer             Pointer to the Buffer allocated.
+  @retval NULL               if no Buffer was found.
+
+**/
+VOID *
+AllocateGlobalBuffer (
+  IN UINT32   Size,
+  IN BOOLEAN  AllocatePage
+  )
+{
+  VOID                       *Buffer;
+  EFI_HOB_MEMORY_ALLOCATION  *MemoryAllocationHob;
+  EFI_PEI_HOB_POINTERS       Hob;
+
+  Buffer = NULL;
+  if (!AllocatePage) {
+    Buffer = BuildGuidHob (&gEdkiiProtectedVariableGlobalGuid, Size);
+  }
+
+  if (Buffer == NULL) {
+    //
+    // Use the AllocatePages() to get over size limit of general GUID-ed HOB.
+    //
+    Buffer = AllocatePages (EFI_SIZE_TO_PAGES (Size));
+    if (Buffer == NULL) {
+      ASSERT_EFI_ERROR (EFI_OUT_OF_RESOURCES);
+      return NULL;
+    }
+
+    //
+    // Mark the HOB holding the pages just allocated so that it can be
+    // identified later.
+    //
+    MemoryAllocationHob = NULL;
+    Hob.Raw             = GetFirstHob (EFI_HOB_TYPE_MEMORY_ALLOCATION);
+    while (Hob.Raw != NULL) {
+      MemoryAllocationHob = (EFI_HOB_MEMORY_ALLOCATION *)Hob.Raw;
+      if ((UINTN)Buffer == (UINTN)MemoryAllocationHob->AllocDescriptor.MemoryBaseAddress) {
+        CopyGuid (
+          &MemoryAllocationHob->AllocDescriptor.Name,
+          &gEdkiiProtectedVariableGlobalGuid
+          );
+        break;
+      }
+
+      Hob.Raw = GET_NEXT_HOB (Hob);
+      Hob.Raw = GetNextHob (EFI_HOB_TYPE_MEMORY_ALLOCATION, Hob.Raw);
+    }
+  }
+
+  return Buffer;
+}
+
+/**
+  Callback use to re-verify all variables and cache them in memory.
+
+  @param[in] PeiServices          General purpose services available to every PEIM.
+  @param[in] NotifyDescriptor     The notification structure this PEIM registered on install.
+  @param[in] Ppi                  The memory discovered PPI.  Not used.
+
+  @retval EFI_SUCCESS             The function completed successfully.
+  @retval others                  There's error in MP initialization.
+**/
+EFI_STATUS
+EFIAPI
+MemoryDiscoveredPpiNotifyCallback (
+  IN EFI_PEI_SERVICES           **PeiServices,
+  IN EFI_PEI_NOTIFY_DESCRIPTOR  *NotifyDescriptor,
+  IN VOID                       *Ppi
+  )
+{
+  EFI_STATUS                     Status;
+  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn;
+  PROTECTED_VARIABLE_GLOBAL      *Global;
+  VARIABLE_DIGEST                *VarDig;
+  PROTECTED_VARIABLE_INFO        VarInfo;
+  VOID                           *Buffer;
+  UINT32                         VarSize;
+  INTN                           Result;
+
+  Status = GetProtectedVariableGlobal (&Global);
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
+  ContextIn = GET_CNTX (Global);
+
+  VarSize = Global->VariableNumber * MAX_VARIABLE_SIZE;
+  Buffer  = AllocateGlobalBuffer (VarSize, TRUE);
+
+  //
+  // It's safe to store the pointer in Global->VariableCache, which has been
+  // cleared by above calling of GetProtectedVariableGlobal().
+  //
+  Global->VariableCache     = GET_ADRS (Buffer);
+  Global->VariableCacheSize = EFI_SIZE_TO_PAGES (VarSize);
+
+  //
+  // Traverse all valid variables.
+  //
+  VarDig = VAR_DIG_PTR (Global->VariableDigests);
+  while (VarDig != NULL) {
+    if (VarDig->CacheIndex == VAR_INDEX_INVALID) {
+      ASSERT (VarDig->StoreIndex != VAR_INDEX_INVALID);
+
+      VarSize  =  VARIABLE_HEADER_SIZE (Global->Flags.Auth);
+      VarSize += VarDig->NameSize + GET_PAD_SIZE (VarDig->NameSize);
+      VarSize += VarDig->DataSize + GET_PAD_SIZE (VarDig->DataSize);
+      VarSize  = HEADER_ALIGN (VarSize);
+
+      //
+      // Note the variable might be in unconsecutive space.
+      //
+      ZeroMem (&VarInfo, sizeof (VarInfo));
+      VarInfo.StoreIndex = VarDig->StoreIndex;
+      VarInfo.Buffer     = Buffer;
+      VarInfo.Flags.Auth = VarDig->Flags.Auth;
+
+      Status = ContextIn->GetVariableInfo (&VarInfo);
+      ASSERT_EFI_ERROR (Status);
+      //
+      // VerifyVariableDigest() refers to CipherData for raw data.
+      //
+      VarInfo.CipherData     = VarInfo.Header.Data;
+      VarInfo.CipherDataSize = (UINT32)VarInfo.Header.DataSize;
+
+      //
+      // Make sure that the cached copy is not compromised.
+      //
+      Status = VerifyVariableDigest (Global, &VarInfo, VarDig);
+      if (EFI_ERROR (Status)) {
+        REPORT_STATUS_CODE (
+          EFI_ERROR_CODE | EFI_ERROR_UNRECOVERED,
+          (PcdGet32 (PcdStatusCodeVariableIntegrity) | (Status & 0xFF))
+          );
+        ASSERT_EFI_ERROR (Status);
+        CpuDeadLoop ();
+      }
+
+      //
+      // Simply use the cache address as CacheIndex of the variable.
+      //
+      VarDig->CacheIndex = GET_ADRS (Buffer);
+      Buffer             = (UINT8 *)Buffer + MAX_VARIABLE_SIZE;
+    } else {
+      Result = StrnCmp (
+                 VAR_DIG_NAME (VarDig),
+                 METADATA_HMAC_VARIABLE_NAME,
+                 METADATA_HMAC_VARIABLE_NAME_SIZE
+                 );
+      if (Result == 0) {
+        CopyMem (
+          Buffer,
+          GET_BUFR (Global->GlobalSelf + (Global->StructSize - GetMetaDataHmacVarSize (Global->Flags.Auth))),
+          GetMetaDataHmacVarSize (Global->Flags.Auth)
+          );
+
+        //
+        // Simply use the cache address as CacheIndex of the variable.
+        //
+        VarDig->CacheIndex = GET_ADRS (Buffer);
+        Buffer             = (UINT8 *)Buffer + MAX_VARIABLE_SIZE;
+      }
+    }
+
+    VarDig = VAR_DIG_NEXT (VarDig);
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Callback use to perform variable integrity check.
+
+  @param[in] PeiServices          General purpose services available to every PEIM.
+  @param[in] NotifyDescriptor     The notification structure this PEIM registered on install.
+  @param[in] Ppi                  The memory discovered PPI.  Not used.
+
+  @retval EFI_SUCCESS             The function completed successfully.
+  @retval others                  There's error in MP initialization.
+**/
+EFI_STATUS
+EFIAPI
+VariableStoreDiscoveredPpiNotifyCallback (
+  IN EFI_PEI_SERVICES           **PeiServices,
+  IN EFI_PEI_NOTIFY_DESCRIPTOR  *NotifyDescriptor,
+  IN VOID                       *Ppi
+  )
+{
+  EFI_STATUS                     Status;
+  EFI_HOB_GUID_TYPE              *GuidHob;
+  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn;
+
+  GuidHob = GetFirstGuidHob (&gEdkiiProtectedVariableContextGuid);
+  if (GuidHob != NULL) {
+    ContextIn = (PROTECTED_VARIABLE_CONTEXT_IN *)GET_GUID_HOB_DATA (GuidHob);
+  } else {
+    ASSERT (GuidHob == NULL);
+  }
+
+  Status = ContextIn->IsHobVariableStoreAvailable ();
+
+  if (Status == EFI_NOT_READY) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
+  Status = PerformVariableIntegrityCheck (ContextIn);
+
+  return Status;
+}
+
+EFI_PEI_NOTIFY_DESCRIPTOR  mPostMemNotifyList[] = {
+  {
+    (EFI_PEI_PPI_DESCRIPTOR_NOTIFY_CALLBACK | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),
+    &gEfiPeiMemoryDiscoveredPpiGuid,
+    MemoryDiscoveredPpiNotifyCallback
+  }
+};
+
+EFI_PEI_NOTIFY_DESCRIPTOR  mVariableStoreNotifyList[] = {
+  {
+    (EFI_PEI_PPI_DESCRIPTOR_NOTIFY_CALLBACK | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),
+    &gEfiPeiVariableStoreDiscoveredPpiGuid,
+    VariableStoreDiscoveredPpiNotifyCallback
+  }
+};
+
+/**
+
+  Get global data structure used to process protected variable.
+
+  @param[out]   Global      Pointer to global configuration data.
+
+  @retval EFI_SUCCESS         Get requested structure successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+GetProtectedVariableGlobal (
+  OUT PROTECTED_VARIABLE_GLOBAL  **Global OPTIONAL
+  )
+{
+  return GetProtectedVariableGlobalFromHob (Global);
+}
+
+/**
+
+  Get context data structure used to process protected variable.
+
+  @param[out]   ContextIn   Pointer to context provided by variable runtime services.
+
+  @retval EFI_SUCCESS         Get requested structure successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+GetProtectedVariableContext (
+  PROTECTED_VARIABLE_CONTEXT_IN  **ContextIn  OPTIONAL
+  )
+{
+  EFI_HOB_GUID_TYPE  *GuidHob;
+
+  GuidHob = GetFirstGuidHob (&gEdkiiProtectedVariableContextGuid);
+  if (GuidHob != NULL) {
+    *ContextIn = (PROTECTED_VARIABLE_CONTEXT_IN *)GET_GUID_HOB_DATA (GuidHob);
+    return EFI_SUCCESS;
+  }
+
+  return EFI_NOT_FOUND;
+}
+
+/**
+  Verify the HMAC value stored in MetaDataHmacVar against all valid and
+  protected variables in storage.
+
+  @param[in,out]  Global          Pointer to global configuration data.
+
+  @retval   EFI_SUCCESS           The HMAC value matches.
+  @retval   EFI_ABORTED           Error in HMAC value calculation.
+  @retval   EFI_VOLUME_CORRUPTED  Inconsistency found in NV variable storage.
+  @retval   EFI_COMPROMISED_DATA  The HMAC value doesn't match.
+
+**/
+EFI_STATUS
+VerifyMetaDataHmac (
+  IN OUT  PROTECTED_VARIABLE_GLOBAL  *Global
+  )
+{
+  EFI_STATUS       Status;
+  VARIABLE_DIGEST  *VariableDig;
+  UINT32           Counter1;
+  UINT32           Counter2;
+  VOID             *Hmac1;
+  VOID             *Hmac2;
+  UINT8            HmacVal1[METADATA_HMAC_SIZE];
+  UINT8            HmacVal2[METADATA_HMAC_SIZE];
+
+  Hmac1 = NULL;
+  Hmac2 = HmacSha256New ();
+  if (Hmac2 == NULL) {
+    ASSERT (Hmac2 != NULL);
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  if (!HmacSha256SetKey (Hmac2, Global->MetaDataHmacKey, sizeof (Global->MetaDataHmacKey))) {
+    ASSERT (FALSE);
+    Status = EFI_ABORTED;
+    goto Done;
+  }
+
+  //
+  // Retrieve the RPMC counter value.
+  //
+  Status = RequestMonotonicCounter (RPMC_COUNTER_1, &Counter1);
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    goto Done;
+  }
+
+  Status = RequestMonotonicCounter (RPMC_COUNTER_2, &Counter2);
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    goto Done;
+  }
+
+  //
+  // Counter1 must be either equal to Counter2 or just one step ahead of Counter2.
+  //
+  if ((Counter1 > Counter2) && ((Counter1 - Counter2) > 1)) {
+    Status = EFI_COMPROMISED_DATA;
+    goto Done;
+  }
+
+  VariableDig = VAR_DIG_PTR (Global->VariableDigests);
+  while (VariableDig != NULL) {
+    //
+    // Only take valid protected variables into account.
+    //
+    if (VariableDig->Flags.Protected && VariableDig->Flags.Valid) {
+      if (!HmacSha256Update (
+             Hmac2,
+             VAR_DIG_VALUE (VariableDig),
+             VariableDig->DigestSize
+             ))
+      {
+        ASSERT (FALSE);
+        Status = EFI_ABORTED;
+        goto Done;
+      }
+    }
+
+    VariableDig = VAR_DIG_NEXT (VariableDig);
+  }
+
+  //
+  // If two MetaDataHmacVariable were found, check which one is valid. We might
+  // need two HMAC values to check against: one for Counter1, one for Counter2.
+  //
+  if (  (Global->Unprotected[IndexHmacAdded] != VAR_INDEX_INVALID)
+     && (Global->Unprotected[IndexHmacInDel] != VAR_INDEX_INVALID)
+     && (Counter1 != Counter2))
+  {
+    //
+    // Might need to check Counter1. There must be something wrong in last boot.
+    //
+    Hmac1 = HmacSha256New ();
+    if ((Hmac1 == NULL) || !HmacSha256Duplicate (Hmac2, Hmac1)) {
+      ASSERT (FALSE);
+      Status = EFI_OUT_OF_RESOURCES;
+      goto Done;
+    }
+
+    if (  !HmacSha256Update (Hmac1, &Counter1, sizeof (Counter1))
+       || !HmacSha256Final (Hmac1, HmacVal1))
+    {
+      ASSERT (FALSE);
+      Status = EFI_ABORTED;
+      goto Done;
+    }
+  }
+
+  //
+  // Always check Counter2.
+  //
+  if (  !HmacSha256Update (Hmac2, &Counter2, sizeof (Counter2))
+     || !HmacSha256Final (Hmac2, HmacVal2))
+  {
+    ASSERT (FALSE);
+    Status = EFI_ABORTED;
+    goto Done;
+  }
+
+  //
+  //  When writing (update or add) a variable, there must be following steps
+  //  performed:
+  //
+  //    A - Increment Counter1
+  //    B - Mark old MetaDataHmacVar as VAR_IN_DELETED_TRANSITION
+  //    C - Calculate new HMAC value against Counter2+1,
+  //        and force-add a new MetaDataHmacVar with state of VAR_ADDED
+  //    D - Write the new protected variable
+  //    E - Increment Counter2
+  //    F - Mark old MetaDataHmacVar as VAR_DELETED
+  //
+  Status = EFI_COMPROMISED_DATA;
+  if (  (Global->Unprotected[IndexHmacAdded] != VAR_INDEX_INVALID)
+     && (Global->Unprotected[IndexHmacInDel] == VAR_INDEX_INVALID))
+  {
+    if (CompareMem (
+          VAR_DIG_VALUE (VAR_DIG_PTR (Global->Unprotected[IndexHmacAdded])),
+          HmacVal2,
+          METADATA_HMAC_SIZE
+          ) == 0)
+    {
+      //
+      //
+      // + A - Increment Counter1
+      //   B - Mark old MetaDataHmacVar as VAR_IN_DELETED_TRANSITION
+      //   C - Calculate new HMAC value against Counter2+1,
+      //       and force-add a new MetaDataHmacVar with state of VAR_ADDED
+      //   D - Write the new protected variable
+      //   E - Increment Counter2
+      //   F - Mark old MetaDataHmacVar as VAR_DELETED
+      //
+      // or,
+      //
+      // + A - Increment Counter1
+      // + B - Mark old MetaDataHmacVar as VAR_IN_DELETED_TRANSITION
+      // + C - Calculate new HMAC value against Counter2+1,
+      //       and force-add a new MetaDataHmacVar with state of VAR_ADDED
+      // + D - Write the new protected variable
+      // + E - Increment Counter2
+      // + F - Mark old MetaDataHmacVar as VAR_DELETED
+      //
+      Status = EFI_SUCCESS;
+
+      VAR_DIG_PTR (Global->Unprotected[IndexHmacAdded])->Flags.Valid = TRUE;
+    }
+  } else if (  (Global->Unprotected[IndexHmacAdded] == VAR_INDEX_INVALID)
+            && (Global->Unprotected[IndexHmacInDel] != VAR_INDEX_INVALID))
+  {
+    if (CompareMem (
+          VAR_DIG_VALUE (VAR_DIG_PTR (Global->Unprotected[IndexHmacInDel])),
+          HmacVal2,
+          METADATA_HMAC_SIZE
+          ) == 0)
+    {
+      //
+      // + A - Increment Counter1
+      // + B - Mark old MetaDataHmacVar as VAR_IN_DELETED_TRANSITION
+      //   C - Calculate new HMAC value against Counter2+1,
+      //       and force-add a new MetaDataHmacVar with state of VAR_ADDED
+      //   D - Write the new protected variable
+      //   E - Increment Counter2
+      //   F - Mark old MetaDataHmacVar as VAR_DELETED
+      //
+      Status = EFI_SUCCESS;
+
+      VAR_DIG_PTR (Global->Unprotected[IndexHmacInDel])->Flags.Valid = TRUE;
+    }
+  } else if (  (Global->Unprotected[IndexHmacAdded] != VAR_INDEX_INVALID)
+            && (Global->Unprotected[IndexHmacInDel] != VAR_INDEX_INVALID))
+  {
+    if (Counter1 > Counter2) {
+      if (CompareMem (
+            VAR_DIG_VALUE (VAR_DIG_PTR (Global->Unprotected[IndexHmacInDel])),
+            HmacVal2,
+            METADATA_HMAC_SIZE
+            ) == 0)
+      {
+        //
+        // + A - Increment Counter1
+        // + B - Mark old MetaDataHmacVar as VAR_IN_DELETED_TRANSITION
+        // + C - Calculate new HMAC value against Counter2+1,
+        //       and force-add a new MetaDataHmacVar with state VAR_ADDED
+        //   D - Write the new protected variable
+        //   E - Increment Counter2
+        //   F - Mark old MetaDataHmacVar as VAR_DELETED
+        //
+        Status = EFI_SUCCESS;
+
+        VAR_DIG_PTR (Global->Unprotected[IndexHmacAdded])->Flags.Valid = FALSE;
+        VAR_DIG_PTR (Global->Unprotected[IndexHmacInDel])->Flags.Valid = TRUE;
+      } else if (CompareMem (
+                   VAR_DIG_VALUE (VAR_DIG_PTR (Global->Unprotected[IndexHmacAdded])),
+                   HmacVal1,
+                   METADATA_HMAC_SIZE
+                   ) == 0)
+      {
+        //
+        // + A - Increment Counter1
+        // + B - Mark old MetaDataHmacVar as VAR_IN_DELETED_TRANSITION
+        // + C - Calculate new HMAC value against Counter2+1,
+        //       and force-add a new MetaDataHmacVar with state of VAR_ADDED
+        // + D - Write the new protected variable
+        //   E - Increment Counter2
+        //   F - Mark old MetaDataHmacVar as VAR_DELETED
+        //
+        Status = EFI_SUCCESS;
+
+        VAR_DIG_PTR (Global->Unprotected[IndexHmacAdded])->Flags.Valid = TRUE;
+        VAR_DIG_PTR (Global->Unprotected[IndexHmacInDel])->Flags.Valid = FALSE;
+      }
+    } else {
+      if (CompareMem (
+            VAR_DIG_VALUE (VAR_DIG_PTR (Global->Unprotected[IndexHmacAdded])),
+            HmacVal2,
+            METADATA_HMAC_SIZE
+            ) == 0)
+      {
+        //
+        // + A - Increment Counter1
+        // + B - Mark old MetaDataHmacVar as VAR_IN_DELETED_TRANSITION
+        // + C - Calculate new HMAC value against Counter2+1,
+        //       and force-add a new MetaDataHmacVar with state of VAR_ADDED
+        // + D - Write the new protected variable
+        // + E - Increment Counter2
+        //   F - Mark old MetaDataHmacVar as VAR_DELETED
+        //
+        Status = EFI_SUCCESS;
+
+        VAR_DIG_PTR (Global->Unprotected[IndexHmacAdded])->Flags.Valid = TRUE;
+        VAR_DIG_PTR (Global->Unprotected[IndexHmacInDel])->Flags.Valid = FALSE;
+      }
+    }
+  } else {
+    //
+    // There must be logic error or variable written to storage skipped
+    // the protected variable service, if code reaches here.
+    //
+    ASSERT (FALSE);
+  }
+
+Done:
+  if (Hmac1 != NULL) {
+    HmacSha256Free (Hmac1);
+  }
+
+  if (Hmac2 != NULL) {
+    HmacSha256Free (Hmac2);
+  }
+
+  return Status;
+}
+
+/**
+  Collect variable digest information.
+
+  This information is collected to be used to for integrity check.
+
+  @param[in]       Global             Pointer to global configuration data.
+  @param[in]       ContextIn          Pointer to variable service context needed by
+                                      protected variable.
+  @param[in, out]  DigestBuffer       Base address of digest of each variable.
+  @param[out]      DigestBufferSize   Digest size of one variable if DigestBuffer is NULL.
+                                      Size of DigestBuffer if DigestBuffer is NOT NULL.
+  @param[out]      VariableNumber     Number of valid variables.
+
+  @retval   EFI_SUCCESS             Successfully retreived variable digest.
+  @retval   EFI_INVALID_PARAMETER   One ore more parameters are invalid.
+  @retval   EFI_OUT_OF_RESOURCES    Unable to allocate memory.
+  @retval   EFI_BUFFER_TOO_SMALL    The DigestBufferSize pass in is too small.
+
+**/
+EFI_STATUS
+CollectVariableDigestInfo (
+  IN      PROTECTED_VARIABLE_GLOBAL      *Global,
+  IN      PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn,
+  IN  OUT VOID                           *DigestBuffer OPTIONAL,
+  OUT UINT32                             *DigestBufferSize OPTIONAL,
+  OUT UINT32                             *VariableNumber OPTIONAL
+  )
+{
+  EFI_STATUS                  Status;
+  PROTECTED_VARIABLE_INFO     VarInfo;
+  UINT32                      VarNum;
+  UINT32                      DigSize;
+  VARIABLE_DIGEST             *VarDig;
+  EFI_TIME                    TimeStamp;
+  UNPROTECTED_VARIABLE_INDEX  VarIndex;
+
+  //
+  // This function might be called before Global is initialized. In that case,
+  // Global must be NULL but not ContextIn.
+  //
+  if ((Global == NULL) && (ContextIn == NULL)) {
+    ASSERT (Global != NULL || ContextIn != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  if ((Global == NULL) && (DigestBuffer != NULL)) {
+    ASSERT (Global != NULL && DigestBuffer != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  if (  (DigestBuffer != NULL)
+     && ((DigestBufferSize == NULL) || (*DigestBufferSize == 0)))
+  {
+    ASSERT (
+      DigestBuffer != NULL
+           && DigestBufferSize != NULL && *DigestBufferSize > 0
+      );
+    return EFI_INVALID_PARAMETER;
+  }
+
+  if ((Global != NULL) && (ContextIn == NULL)) {
+    ContextIn = GET_CNTX (Global);
+  }
+
+  DigSize = 0;
+  VarNum  = 0;
+  VarDig  = NULL;
+
+  ZeroMem (&VarInfo, sizeof (VarInfo));
+  VarInfo.StoreIndex = VAR_INDEX_INVALID; // To get the first variable.
+
+  if ((Global != NULL) &&
+      (Global->VariableCache != 0) &&
+      (Global->VariableCacheSize > 0))
+  {
+    //
+    // Use the variable cache to hold a copy of one variable.
+    //
+    VarInfo.Buffer = GET_BUFR (Global->VariableCache);
+  } else {
+    //
+    // Allocate a buffer to hold a copy of one variable
+    //
+    VarInfo.Buffer = AllocatePages (EFI_SIZE_TO_PAGES (MAX_VARIABLE_SIZE));
+    if (VarInfo.Buffer == NULL) {
+      ASSERT (VarInfo.Buffer != NULL);
+      return EFI_OUT_OF_RESOURCES;
+    }
+  }
+
+  if ((DigestBuffer != NULL) && (*DigestBufferSize > 0)) {
+    VarDig = DigestBuffer;
+  }
+
+  while (TRUE) {
+    if (VarDig != NULL) {
+      if (DigSize >= (*DigestBufferSize)) {
+        //
+        // Out of buffer.
+        //
+        break;
+      }
+
+      VarInfo.Header.VendorGuid   = &VarDig->VendorGuid;
+      VarInfo.Header.VariableName = VAR_DIG_NAME (VarDig);
+      VarInfo.Header.NameSize     = (UINTN)DigestBuffer + (UINTN)*DigestBufferSize
+                                    - (UINTN)VarInfo.Header.VariableName;
+      VarInfo.Header.TimeStamp = &TimeStamp;
+      VarInfo.Header.Data      = NULL;
+    } else {
+      ZeroMem ((VOID *)&VarInfo.Header, sizeof (VarInfo.Header));
+    }
+
+    Status = ContextIn->GetNextVariableInfo (&VarInfo);
+    if (EFI_ERROR (Status)) {
+      break;
+    }
+
+    //
+    // Skip deleted variables.
+    //
+    if (  (VarInfo.Header.State != VAR_ADDED)
+       && (VarInfo.Header.State != (VAR_ADDED & VAR_IN_DELETED_TRANSITION)))
+    {
+      continue;
+    }
+
+    if (Global != NULL) {
+      Global->Flags.Auth &= VarInfo.Flags.Auth;
+    }
+
+    VarNum  += 1;
+    DigSize += (UINT32)(sizeof (VARIABLE_DIGEST)
+                        + VarInfo.Header.NameSize
+                        + METADATA_HMAC_SIZE);
+    if ((DigestBuffer != NULL) && (DigSize > *DigestBufferSize)) {
+      ASSERT (DigSize <= *DigestBufferSize);
+      return EFI_BUFFER_TOO_SMALL;
+    }
+
+    if (VarDig != NULL) {
+      VarDig->Prev       = 0;
+      VarDig->Next       = 0;
+      VarDig->State      = VarInfo.Header.State;
+      VarDig->Attributes = VarInfo.Header.Attributes;
+      VarDig->DataSize   = (UINT32)VarInfo.Header.DataSize;
+      VarDig->NameSize   = (UINT16)VarInfo.Header.NameSize;
+      VarDig->DigestSize = METADATA_HMAC_SIZE;
+      VarDig->StoreIndex = VarInfo.StoreIndex;
+
+      if ((VarInfo.Buffer != NULL) && ((UINTN)VarInfo.Buffer != Global->VariableCache)) {
+        VarDig->CacheIndex = GET_ADRS (VarInfo.Buffer);
+      } else {
+        VarDig->CacheIndex = VAR_INDEX_INVALID;
+      }
+
+      VarDig->Flags.Auth  = VarInfo.Flags.Auth;
+      VarDig->Flags.Valid = TRUE;
+
+      VarIndex = CheckKnownUnprotectedVariable (Global, &VarInfo);
+      if (VarIndex >= UnprotectedVarIndexMax) {
+        //
+        // Check information relating to encryption, if enabled.
+        //
+        VarDig->Flags.Encrypted = FALSE;
+        if ((VarInfo.Header.Data != NULL) && (VarInfo.Header.DataSize > 0)) {
+          VarInfo.CipherData     = NULL;
+          VarInfo.CipherDataSize = 0;
+          VarInfo.PlainData      = NULL;
+          VarInfo.PlainDataSize  = 0;
+          Status                 = GetCipherDataInfo (&VarInfo);
+          if (!EFI_ERROR (Status)) {
+            //
+            // Discovered encrypted variable mark variable to be
+            // encrypted on the next SetVariable() operation
+            //
+            VarDig->Flags.Encrypted = PcdGetBool (PcdProtectedVariableConfidentiality);
+          } else {
+            VarInfo.PlainData        = VarInfo.Header.Data;
+            VarInfo.PlainDataSize    = (UINT32)VarInfo.Header.DataSize;
+            VarInfo.CipherDataType   = 0;
+            VarInfo.CipherHeaderSize = 0;
+            if (Status == EFI_NOT_FOUND) {
+              //
+              // Found variable that is not encrypted mark variable to be
+              // encrypted on the next SetVariable() operation
+              //
+              VarDig->Flags.Encrypted = PcdGetBool (PcdProtectedVariableConfidentiality);
+            }
+          }
+        }
+
+        //
+        // Variable is protected
+        //
+        VarDig->Flags.Protected = PcdGetBool (PcdProtectedVariableIntegrity);
+        VarDig->PlainDataSize   = VarInfo.PlainDataSize;
+
+        //
+        // Calculate digest only for protected variable.
+        //
+        Status = GetVariableDigest (Global, &VarInfo, VAR_DIG_VALUE (VarDig));
+        if (EFI_ERROR (Status)) {
+          return Status;
+        }
+
+        //
+        // Keep the VarDig in an ordered list.
+        //
+        InsertVariableDigestNode (Global, VarDig, CompareVariableDigestInfo);
+      } else {
+        VarDig->Flags.Protected = FALSE;
+        VarDig->Flags.Encrypted = FALSE;
+        VarDig->PlainDataSize   = VarDig->DataSize;
+
+        //
+        // Make use of VARIABLE_DIGEST->DigestValue to cache HMAC value from
+        // MetaDataHmacVar, which doesn't need a digest value (only protected
+        // variables need it for integrity check).
+        //
+        if ((VarIndex == IndexHmacInDel) || (VarIndex == IndexHmacAdded)) {
+          if (VarDig->State == VAR_ADDED) {
+            VarIndex = IndexHmacAdded;
+          } else {
+            VarIndex = IndexHmacInDel;
+          }
+        }
+
+        Global->Unprotected[VarIndex] = VAR_DIG_ADR (VarDig);
+
+        if ((VarInfo.Header.Data != NULL) && (VarDig->DataSize <= VarDig->DigestSize)) {
+          CopyMem (VAR_DIG_VALUE (VarDig), VarInfo.Header.Data, VarDig->DataSize);
+        }
+
+        //
+        // Don't add the VarDig for MetaDataHmacVar into the linked list now.
+        // Do it after the HMAC has been validated.
+        //
+        if ((VarIndex != IndexHmacInDel) || (VarIndex != IndexHmacAdded)) {
+          InsertVariableDigestNode (Global, VarDig, CompareVariableDigestInfo);
+        }
+      }
+
+      VarDig = (VARIABLE_DIGEST *)((UINTN)VarDig + VAR_DIG_END (VarDig));
+    }
+  }
+
+  if (EFI_ERROR (Status) && (Status != EFI_NOT_FOUND)) {
+    return Status;
+  }
+
+  if (DigestBufferSize != NULL) {
+    *DigestBufferSize = DigSize;
+  }
+
+  if (VariableNumber != NULL) {
+    *VariableNumber = VarNum;
+  }
+
+  if ((Global == NULL) && (VarInfo.Buffer != NULL)) {
+    //
+    // Free Buffer
+    //
+    FreePages (VarInfo.Buffer, EFI_SIZE_TO_PAGES (MAX_VARIABLE_SIZE));
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+
+  Perform for protected variable integrity check.
+
+  If this initialization failed upon any error, the whole variable services
+  should not be used.  A system reset might be needed to re-construct NV
+  variable storage to be the default state.
+
+  @param[in]  ContextIn   Pointer to variable service context needed by
+                          protected variable.
+
+  @retval EFI_SUCCESS               Protected variable services are ready.
+  @retval EFI_INVALID_PARAMETER     If ContextIn == NULL or something missing or
+                                    mismatching in the content in ContextIn.
+  @retval EFI_COMPROMISED_DATA      If failed to check integrity of protected variables.
+  @retval EFI_OUT_OF_RESOURCES      Fail to allocate enough resource.
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+PerformVariableIntegrityCheck (
+  IN  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn
+  )
+{
+  EFI_STATUS                 Status;
+  UINT32                     HobDataSize;
+  UINT32                     VarNumber;
+  VOID                       *Buffer;
+  PROTECTED_VARIABLE_GLOBAL  *Global;
+  VARIABLE_DIGEST            *DigBuffer;
+  UINT32                     DigBufferSize;
+  UINT32                     HmacMetaDataSize;
+  UINTN                      Index;
+  BOOLEAN                    PreviousKey;
+  EFI_HOB_GUID_TYPE          *GuidHob;
+
+  if ((ContextIn == NULL) || (ContextIn->GetNextVariableInfo == NULL)) {
+    ASSERT (ContextIn != NULL);
+    ASSERT (ContextIn->GetNextVariableInfo != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  ContextIn->StructSize = (ContextIn->StructSize == 0) ? sizeof (*ContextIn)
+                                                       : ContextIn->StructSize;
+
+  //
+  // Enumerate all variables first to collect info for resource allocation.
+  //
+  DigBufferSize = 0;
+  Status        = CollectVariableDigestInfo (
+                    NULL,
+                    ContextIn,
+                    NULL,
+                    &DigBufferSize,
+                    &VarNumber
+                    );
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return EFI_VOLUME_CORRUPTED;
+  }
+
+  //
+  // Allocate buffer for Global. Memory layout:
+  //
+  //      Global
+  //      Digest context
+  //      Variable Digest List
+  //      HmacMetaData
+  //
+  // To save precious NEM space of processor, variable cache will not be
+  // allocated at this point until physical memory is ready for use.
+  //
+  HmacMetaDataSize = (UINT32)GetMetaDataHmacVarSize (TRUE);
+  HobDataSize      = sizeof (PROTECTED_VARIABLE_GLOBAL)
+                     + (UINT32)DIGEST_CONTEXT_SIZE
+                     + DigBufferSize
+                     + HmacMetaDataSize;
+  Buffer = AllocateGlobalBuffer (HobDataSize, FALSE);
+  if (Buffer == NULL) {
+    ASSERT (Buffer != NULL);
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  Global                = (PROTECTED_VARIABLE_GLOBAL *)((UINTN)Buffer);
+  Global->DigestContext = GET_ADRS (Global + 1);
+
+  if (DigBufferSize > 0) {
+    DigBuffer = (VARIABLE_DIGEST *)(UINTN)(Global->DigestContext + DIGEST_CONTEXT_SIZE);
+    ZeroMem (DigBuffer, DigBufferSize);
+  } else {
+    DigBuffer = NULL;
+  }
+
+  //
+  // Keep a copy of ContextIn in HOB for later uses.
+  //
+  Global->GlobalSelf = GET_ADRS (Global);
+  Global->ContextIn  = GET_ADRS (ContextIn);
+
+  Global->StructVersion = PROTECTED_VARIABLE_CONTEXT_OUT_STRUCT_VERSION;
+  Global->StructSize    = HobDataSize;
+
+  Global->VariableNumber  = VarNumber;
+  Global->VariableDigests = 0;
+
+  Global->Flags.Auth       = TRUE;
+  Global->Flags.WriteInit  = FALSE;
+  Global->Flags.WriteReady = FALSE;
+
+  GuidHob = GetFirstGuidHob (&gEfiAuthenticatedVariableGuid);
+  if (GuidHob == NULL) {
+    GuidHob = GetFirstGuidHob (&gEfiVariableGuid);
+    if (GuidHob != NULL) {
+      Global->Flags.Auth = FALSE;
+    }
+  }
+
+  Global->Flags.RecoveryMode = (GuidHob != NULL);
+
+  //
+  // Before physical memory is ready, we cannot cache all variables in the very
+  // limited NEM space. But we still need to reserve buffer to hold data of
+  // one variable as well as context for integrity check (HMAC calculation).
+  //
+  Global->VariableCacheSize = MAX_VARIABLE_SIZE;
+  Buffer                    = AllocatePages (EFI_SIZE_TO_PAGES (Global->VariableCacheSize));
+  if (Buffer == NULL) {
+    ASSERT (Buffer != NULL);
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  Global->VariableCache        = GET_ADRS (Buffer);
+  Global->LastAccessedVariable = VAR_INDEX_INVALID;
+
+  for (Index = 0; Index < UnprotectedVarIndexMax; ++Index) {
+    Global->Unprotected[Index] = VAR_INDEX_INVALID;
+  }
+
+  //
+  // Re-enumerate all NV variables and build digest list.
+  //
+  Status = CollectVariableDigestInfo (
+             Global,
+             ContextIn,
+             DigBuffer,
+             &DigBufferSize,
+             &VarNumber
+             );
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
+  ASSERT (Global->VariableNumber == VarNumber);
+
+  //
+  // Fix-up number of valid protected variables (i.e. exclude unprotected ones)
+  //
+  for (Index = 0; VarNumber != 0 && Index < UnprotectedVarIndexMax; ++Index) {
+    if (Global->Unprotected[Index] != VAR_INDEX_INVALID) {
+      --VarNumber;
+    }
+  }
+
+  //
+  // Get root key and generate HMAC key.
+  //
+  PreviousKey = FALSE;
+  Status      = GetVariableKey ((VOID *)Global->RootKey, sizeof (Global->RootKey));
+  if (EFI_ERROR (Status)) {
+    ASSERT (FALSE);
+    Status = EFI_COMPROMISED_DATA;
+  }
+
+  //
+  // Derive the MetaDataHmacKey from root key
+  //
+  if (!GenerateMetaDataHmacKey (
+         Global->RootKey,
+         sizeof (Global->RootKey),
+         Global->MetaDataHmacKey,
+         sizeof (Global->MetaDataHmacKey)
+         ))
+  {
+    ASSERT (FALSE);
+    Status = EFI_COMPROMISED_DATA;
+  }
+
+  //
+  // Check the integrity of all NV variables, if any.
+  //
+  if ((  (Global->Unprotected[IndexHmacAdded] != VAR_INDEX_INVALID)
+      || (Global->Unprotected[IndexHmacInDel] != VAR_INDEX_INVALID)))
+  {
+    //
+    // Validate the HMAC stored in variable MetaDataHmacVar.
+    //
+    Status = VerifyMetaDataHmac (Global);
+    if (EFI_ERROR (Status)) {
+      //
+      // Try again with the previous root key if the latest key failed the HMAC validation.
+      //
+      Status = GetVariableKey ((VOID *)Global->RootKey, sizeof (Global->RootKey));
+      if (!EFI_ERROR (Status)) {
+        //
+        // Derive the MetaDataHmacKey from previous root key
+        //
+        if (GenerateMetaDataHmacKey (
+              Global->RootKey,
+              sizeof (Global->RootKey),
+              Global->MetaDataHmacKey,
+              sizeof (Global->MetaDataHmacKey)
+              ) == TRUE)
+        {
+          //
+          // Validate the HMAC stored in variable MetaDataHmacVar.
+          //
+          Status = VerifyMetaDataHmac (Global);
+          if (!EFI_ERROR (Status)) {
+            Status = EFI_COMPROMISED_DATA;
+          }
+        } else {
+          Status = EFI_COMPROMISED_DATA;
+        }
+      }
+    }
+  } else if (Global->Flags.RecoveryMode) {
+    //
+    // Generate the first version of MetaDataHmacVar.
+    //
+    Status = SyncRpmcCounter ();
+    if (!EFI_ERROR (Status)) {
+      Status = RefreshVariableMetadataHmac (Global, NULL, NULL);
+      if (!EFI_ERROR (Status)) {
+        //
+        // MetaDataHmacVar is always calculated against Counter2+1. Updating
+        // RPMCs to match it.
+        //
+        (VOID)IncrementMonotonicCounter (RPMC_COUNTER_1);
+        (VOID)IncrementMonotonicCounter (RPMC_COUNTER_2);
+      }
+    }
+  } else if ((VarNumber > 0) && !Global->Flags.RecoveryMode) {
+    //
+    // There's no MetaDataHmacVar found for protected variables. Suppose
+    // the variable storage is compromised.
+    //
+    Status = EFI_COMPROMISED_DATA;
+  }
+
+  if (EFI_ERROR (Status)) {
+    //
+    // The integrity of variables have been compromised. The platform has to do
+    // something to recover the variable store. But the boot should not go on
+    // anyway this time.
+    //
+    DEBUG ((DEBUG_ERROR, "%a: %d Integrity check Status = %r\n", __FUNCTION__, __LINE__, Status));
+    REPORT_STATUS_CODE (
+      EFI_ERROR_CODE | EFI_ERROR_UNRECOVERED,
+      (PcdGet32 (PcdStatusCodeVariableIntegrity) | EFI_SW_PEI_PC_RECOVERY_BEGIN)
+      );
+ #if defined (EDKII_UNIT_TEST_FRAMEWORK_ENABLED) // Avoid test malfunctioning.
+    return Status;
+ #else
+    ASSERT_EFI_ERROR (Status);
+    CpuDeadLoop ();
+ #endif
+  }
+
+  //
+  // Everything's OK.
+  //
+  REPORT_STATUS_CODE (
+    EFI_PROGRESS_CODE,
+    PcdGet32 (PcdStatusCodeVariableIntegrity)
+    );
+
+  if (GET_BUFR (Global->VariableCacheSize) != NULL) {
+    //
+    // Free Buffer
+    //
+    FreePages (Buffer, EFI_SIZE_TO_PAGES (Global->VariableCacheSize));
+  }
+
+  //
+  // Keep the valid MetaDataHmacVar in the list.
+  //
+  for (Index = 0; Index < IndexPlatformVar; ++Index) {
+    if (  (Global->Unprotected[Index] != VAR_INDEX_INVALID)
+       && VAR_DIG_PTR (Global->Unprotected[Index])->Flags.Valid)
+    {
+      InsertVariableDigestNode (
+        Global,
+        VAR_DIG_PTR (Global->Unprotected[Index]),
+        NULL
+        );
+    }
+  }
+
+  //
+  // Restore the key to the latest one.
+  //
+  if (PreviousKey) {
+    Status = GetVariableKey ((VOID *)Global->RootKey, sizeof (Global->RootKey));
+    ASSERT_EFI_ERROR (Status);
+
+    //
+    // Derive the MetaDataHmacKey from root key
+    //
+    if (!GenerateMetaDataHmacKey (
+           Global->RootKey,
+           sizeof (Global->RootKey),
+           Global->MetaDataHmacKey,
+           sizeof (Global->MetaDataHmacKey)
+           ))
+    {
+      ASSERT (FALSE);
+    }
+  }
+
+  //
+  // Make sure that the RPMC counter is in-sync.
+  //
+  Status = SyncRpmcCounter ();
+
+  //
+  // Setup a hook to migrate data in Global once physical memory is ready.
+  //
+  Status = PeiServicesNotifyPpi (mPostMemNotifyList);
+
+  return Status;
+}
+
+/**
+
+  Initialization for protected variable services.
+
+  If the variable store is available than perform integrity check.
+  Otherwise, defer integrity check until variable store is available.
+
+
+  @param[in]  ContextIn   Pointer to variable service context needed by
+                          protected variable.
+
+  @retval EFI_SUCCESS               Protected variable services are ready.
+  @retval EFI_INVALID_PARAMETER     If ContextIn == NULL or something missing or
+                                    mismatching in the content in ContextIn.
+  @retval EFI_COMPROMISED_DATA      If failed to check integrity of protected variables.
+  @retval EFI_OUT_OF_RESOURCES      Fail to allocate enough resource.
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibInitialize (
+  IN  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn
+  )
+{
+  EFI_STATUS               Status;
+  VOID                     *ContextInHob;
+  PROTECTED_VARIABLE_INFO  VarInfo;
+
+  if ((ContextIn == NULL) || (ContextIn->GetNextVariableInfo == NULL)) {
+    ASSERT (ContextIn != NULL);
+    ASSERT (ContextIn->GetNextVariableInfo != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // Keep a copy of ContextIn in HOB for later uses.
+  //
+  ContextIn->StructSize = (ContextIn->StructSize == 0) ? sizeof (*ContextIn)
+                                                       : ContextIn->StructSize;
+  ContextInHob = BuildGuidHob (&gEdkiiProtectedVariableContextGuid, ContextIn->StructSize);
+  CopyMem (ContextInHob, ContextIn, ContextIn->StructSize);
+
+  //
+  // Discover if Variable Store Info Hob has been published by platform driver.
+  // It contains information regards to HOB or NV Variable Store availability
+  //
+  ZeroMem ((VOID *)&VarInfo.Header, sizeof (VarInfo.Header));
+  VarInfo.StoreIndex = VAR_INDEX_INVALID;
+  VarInfo.Buffer     = AllocatePages (EFI_SIZE_TO_PAGES (MAX_VARIABLE_SIZE));
+  if (VarInfo.Buffer == NULL) {
+    ASSERT (VarInfo.Buffer != NULL);
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  FreePages (VarInfo.Buffer, EFI_SIZE_TO_PAGES ((MAX_VARIABLE_SIZE)));
+
+  Status = ContextIn->GetNextVariableInfo (&VarInfo);
+  if (EFI_ERROR (Status)) {
+    //
+    // Register for platform driver callback when Variable Store is available.
+    //
+    DEBUG ((DEBUG_INFO, "Variable Store is not available. Register for a integrity check callback\n"));
+    Status = PeiServicesNotifyPpi (mVariableStoreNotifyList);
+    return Status;
+  }
+
+  //
+  // HOB Variable store is not available
+  // Assume NV Variable store is available instead
+  // Perform integrity check on NV Variable Store
+  //
+  DEBUG ((DEBUG_INFO, "NV Variable Store is available. Perform integrity check\n"));
+  Status = PerformVariableIntegrityCheck (ContextInHob);
+  return Status;
+}
+
+/**
+
+  Prepare for variable update.
+
+  (Not suppported in PEI phase.)
+
+  @retval EFI_UNSUPPORTED         Updating variable is not supported.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibWriteInit (
+  VOID
+  )
+{
+  ASSERT (FALSE);
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Update a variable with protection provided by this library.
+
+  Not supported in PEI phase.
+
+  @param[in,out]  CurrVariable        Variable to be updated. It's NULL if
+                                      adding a new variable.
+  @param[in]      CurrVariableInDel   In-delete-transition copy of updating variable.
+  @param[in,out]  NewVariable         Buffer of new variable data.
+                                      Buffer of "MetaDataHmacVar" and new
+                                      variable (encrypted).
+  @param[in,out]  NewVariableSize     Size of NewVariable.
+                                      Size of (encrypted) NewVariable and
+                                      "MetaDataHmacVar".
+
+  @retval EFI_UNSUPPORTED         Not support updating variable in PEI phase.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibUpdate (
+  IN  OUT VARIABLE_HEADER  *CurrVariable,
+  IN      VARIABLE_HEADER  *CurrVariableInDel,
+  IN  OUT VARIABLE_HEADER  *NewVariable,
+  IN  OUT UINTN            *NewVariableSize
+  )
+{
+  ASSERT (FALSE);
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Finalize a variable updating after it's written to NV variable storage
+  successfully.
+
+  @param[in]      NewVariable       Buffer of new variables and MetaDataHmacVar.
+  @param[in]      VariableSize      Size of buffer pointed by NewVariable.
+  @param[in]      StoreIndex        StoreIndex to NV variable storage from where the new
+                                    variable and MetaDataHmacVar have been written.
+
+  @retval EFI_UNSUPPORTED           Not support updating variable in PEI phase.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibWriteFinal (
+  IN  VARIABLE_HEADER  *NewVariable,
+  IN  UINTN            VariableSize,
+  IN  UINT64           StoreIndex
+  )
+{
+  ASSERT (FALSE);
+  return EFI_UNSUPPORTED;
+}
diff --git a/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmm.c b/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmm.c
new file mode 100644
index 000000000000..8e964f4cd28d
--- /dev/null
+++ b/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmm.c
@@ -0,0 +1,209 @@
+/** @file
+  Implemention of ProtectedVariableLib for SMM variable services.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <PiDxe.h>
+#include <Uefi.h>
+
+#include "Guid/SmmVariableCommon.h"
+
+#include "Library/MmServicesTableLib.h"
+#include "Library/MemoryAllocationLib.h"
+
+#include "ProtectedVariableInternal.h"
+
+PROTECTED_VARIABLE_CONTEXT_IN  mVariableContextIn = {
+  PROTECTED_VARIABLE_CONTEXT_IN_STRUCT_VERSION,
+  sizeof (PROTECTED_VARIABLE_CONTEXT_IN),
+  0,
+  FromSmmModule,
+  NULL,
+  NULL,
+  NULL,
+  NULL,
+  NULL
+};
+
+PROTECTED_VARIABLE_GLOBAL  mProtectedVariableGlobal = {
+  PROTECTED_VARIABLE_CONTEXT_OUT_STRUCT_VERSION,
+  sizeof (PROTECTED_VARIABLE_GLOBAL),
+  { 0 },
+  { 0 },
+  0,
+  0,
+  0,
+  0,
+  0,
+  0,
+  { 0,                                          0,  0 },
+  0,
+  0,
+  { 0,                                          0,  0, 0}
+};
+
+/**
+
+  Callback function to call variable write.
+
+  @param[in]  Protocol    Not Used.
+  @param[in]  Interface   Not Used.
+  @param[in]  Handle      Not Used.
+
+  @retval EFI_SUCCESS     Protected variable write successful.
+  @retval others          Protected variable write failed.
+
+**/
+EFI_STATUS
+EFIAPI
+VariableWriteProtocolCallback (
+  IN CONST EFI_GUID  *Protocol,
+  IN VOID            *Interface,
+  IN EFI_HANDLE      Handle
+  )
+{
+  EFI_STATUS  Status;
+
+  Status = ProtectedVariableLibWriteInit ();
+  ASSERT_EFI_ERROR (Status);
+
+  return EFI_SUCCESS;
+}
+
+/**
+
+  Initialization for protected variable services.
+
+  If this initialization failed upon any error, the whole variable services
+  should not be used.  A system reset might be needed to re-construct NV
+  variable storage to be the default state.
+
+  @param[in]  ContextIn   Pointer to variable service context needed by
+                          protected variable.
+
+  @retval EFI_SUCCESS               Protected variable services are ready.
+  @retval EFI_INVALID_PARAMETER     If ContextIn == NULL or something missing or
+                                    mismatching in the content in ContextIn.
+  @retval EFI_COMPROMISED_DATA      If failed to check integrity of protected variables.
+  @retval EFI_OUT_OF_RESOURCES      Fail to allocate enough resource.
+  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibInitialize (
+  IN  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn
+  )
+{
+  EFI_STATUS                     Status;
+  PROTECTED_VARIABLE_CONTEXT_IN  *ProtectedVarContext;
+  PROTECTED_VARIABLE_GLOBAL      *OldGlobal;
+  PROTECTED_VARIABLE_GLOBAL      *NewGlobal;
+  VARIABLE_DIGEST                *VarDig;
+  VARIABLE_DIGEST                *NewVarDig;
+  EFI_PHYSICAL_ADDRESS           NewCacheIndex;
+  UINTN                          VarSize;
+  UNPROTECTED_VARIABLE_INDEX     Index;
+
+  if (  (ContextIn == NULL)
+     || (ContextIn->StructVersion != PROTECTED_VARIABLE_CONTEXT_IN_STRUCT_VERSION)
+     || (ContextIn->StructSize != sizeof (PROTECTED_VARIABLE_CONTEXT_IN))
+     || (ContextIn->GetVariableInfo == NULL)
+     || (ContextIn->GetNextVariableInfo == NULL)
+     || (ContextIn->UpdateVariableStore == NULL)
+     || (ContextIn->UpdateVariable == NULL))
+  {
+    ASSERT (ContextIn != NULL);
+    ASSERT (ContextIn->StructVersion == PROTECTED_VARIABLE_CONTEXT_IN_STRUCT_VERSION);
+    ASSERT (ContextIn->StructSize == sizeof (PROTECTED_VARIABLE_CONTEXT_IN));
+    ASSERT (ContextIn->GetVariableInfo != NULL);
+    ASSERT (ContextIn->GetNextVariableInfo != NULL);
+    ASSERT (ContextIn->UpdateVariableStore != NULL);
+    ASSERT (ContextIn->UpdateVariable != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  GetProtectedVariableGlobal (&NewGlobal);
+  ProtectedVarContext = GET_CNTX (NewGlobal);
+  CopyMem (ProtectedVarContext, ContextIn, sizeof (mVariableContextIn));
+  ProtectedVarContext->VariableServiceUser = FromSmmModule;
+
+  //
+  // Get root key and HMAC key from HOB created by PEI variable driver.
+  //
+  Status = GetProtectedVariableGlobalFromHob (&OldGlobal);
+  ASSERT_EFI_ERROR (Status);
+
+  CopyMem ((VOID *)NewGlobal, (CONST VOID *)OldGlobal, sizeof (*OldGlobal));
+
+  //
+  // The keys must not be available outside SMM.
+  //
+  if (ProtectedVarContext->VariableServiceUser == FromSmmModule) {
+    ZeroMem (OldGlobal->RootKey, sizeof (OldGlobal->RootKey));
+    ZeroMem (OldGlobal->MetaDataHmacKey, sizeof (OldGlobal->MetaDataHmacKey));
+  }
+
+  NewGlobal->Flags.WriteInit      = FALSE;
+  NewGlobal->Flags.WriteReady     = FALSE;
+  NewGlobal->LastAccessedVariable = 0;
+  NewGlobal->VariableCache        = GET_ADRS (AllocateZeroPool (MAX_VARIABLE_SIZE));
+  NewGlobal->DigestContext        = GET_ADRS (AllocateZeroPool (DIGEST_CONTEXT_SIZE));
+  if (NewGlobal->DigestContext == 0) {
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  //
+  // Copy over variable from HOB to SMM memory
+  //
+  NewGlobal->VariableDigests = 0;
+  VarDig                     = VAR_DIG_PTR (OldGlobal->VariableDigests);
+  while (VarDig != NULL) {
+    //
+    // Allocate new Var Digest in SMM memory
+    //
+    NewVarDig = (VARIABLE_DIGEST *)AllocateZeroPool (
+                                     sizeof (VARIABLE_DIGEST) + VarDig->NameSize + METADATA_HMAC_SIZE
+                                     );
+    if (NewVarDig == NULL) {
+      ASSERT (NewVarDig != NULL);
+      return EFI_OUT_OF_RESOURCES;
+    }
+
+    CopyMem (NewVarDig, VarDig, sizeof (VARIABLE_DIGEST));
+    NewVarDig->Prev = 0;
+    NewVarDig->Next = 0;
+
+    CopyMem (VAR_DIG_NAME (NewVarDig), VAR_DIG_NAME (VarDig), VarDig->NameSize);
+    CopyMem (VAR_DIG_VALUE (NewVarDig), VAR_DIG_VALUE (VarDig), VarDig->DigestSize);
+
+    VarSize  =  VARIABLE_HEADER_SIZE (NewGlobal->Flags.Auth);
+    VarSize += VarDig->NameSize + GET_PAD_SIZE (VarDig->NameSize);
+    VarSize += VarDig->DataSize + GET_PAD_SIZE (VarDig->DataSize);
+    VarSize  = HEADER_ALIGN (VarSize);
+
+    NewCacheIndex = GET_ADRS (AllocateZeroPool (VarSize));
+    if (GET_BUFR (NewCacheIndex) == NULL) {
+      return EFI_OUT_OF_RESOURCES;
+    }
+
+    CopyMem (GET_BUFR (NewCacheIndex), GET_BUFR (VarDig->CacheIndex), VarSize);
+    NewVarDig->CacheIndex     = NewCacheIndex;
+    NewVarDig->Flags.Freeable = TRUE;
+
+    for (Index = 0; Index < UnprotectedVarIndexMax; ++Index) {
+      if (OldGlobal->Unprotected[Index] == VAR_DIG_ADR (VarDig)) {
+        NewGlobal->Unprotected[Index] = VAR_DIG_ADR (NewVarDig);
+      }
+    }
+
+    InsertVariableDigestNode (NewGlobal, NewVarDig, NULL);
+
+    VarDig = VAR_DIG_NEXT (VarDig);
+  }
+
+  return Status;
+}
diff --git a/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmDxeCommon.c b/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmDxeCommon.c
new file mode 100644
index 000000000000..92ba7cb12763
--- /dev/null
+++ b/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmDxeCommon.c
@@ -0,0 +1,975 @@
+/** @file
+  Implemention of ProtectedVariableLib for SMM variable services.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <PiDxe.h>
+#include <Uefi.h>
+
+#include "Guid/SmmVariableCommon.h"
+
+#include "Library/MmServicesTableLib.h"
+#include "Library/MemoryAllocationLib.h"
+#include <Library/HobLib.h>
+
+#include "ProtectedVariableInternal.h"
+
+/**
+
+  Get context and/or global data structure used to process protected variable.
+
+  @param[out]   Global      Pointer to global configuration data.
+
+  @retval EFI_SUCCESS         Get requested structure successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+GetProtectedVariableGlobal (
+  OUT PROTECTED_VARIABLE_GLOBAL  **Global OPTIONAL
+  )
+{
+  if (Global != NULL) {
+    mProtectedVariableGlobal.ContextIn = GET_ADRS (&mVariableContextIn);
+    *Global                            = &mProtectedVariableGlobal;
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Encrypt given variable data and generate new HMAC value against it.
+
+  @param[in]      Global          Pointer to global configuration data.
+  @param[in,out]  NewVarInfo      Pointer to buffer of new variable data.
+  @param[in,out]  NewVarDig       Pointer to buffer of new variable digest.
+
+  @retval EFI_SUCCESS           No error occurred during the encryption and HMC calculation.
+  @retval EFI_ABORTED           Failed to do HMC calculation.
+  @return EFI_OUT_OF_RESOURCES  Not enough resource to calculate HMC value.
+  @return EFI_NOT_FOUND         The MetaDataHmacVar was not found in storage.
+
+**/
+STATIC
+EFI_STATUS
+UpdateVariableInternal (
+  IN      PROTECTED_VARIABLE_GLOBAL  *Global,
+  IN  OUT PROTECTED_VARIABLE_INFO    *NewVarInfo,
+  IN  OUT VARIABLE_DIGEST            *NewVarDig
+  )
+{
+  EFI_STATUS               Status;
+  PROTECTED_VARIABLE_INFO  CachedVarInfo;
+  VOID                     *Buffer;
+  UINTN                    VarSize;
+
+  if ((NewVarInfo == NULL) || (NewVarDig == NULL)) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // If Add or update variable, encrypt new data first.
+  //
+  if (NewVarInfo->Buffer != NULL) {
+    Status = EFI_UNSUPPORTED;
+
+    if (NewVarDig->Flags.Encrypted) {
+      NewVarInfo->PlainData          = NULL;
+      NewVarInfo->PlainDataSize      = 0;
+      NewVarInfo->CipherData         = NULL;
+      NewVarInfo->CipherDataSize     = 0;
+      NewVarInfo->Key                = Global->RootKey;
+      NewVarInfo->KeySize            = sizeof (Global->RootKey);
+      NewVarInfo->Header.Attributes &= (~EFI_VARIABLE_APPEND_WRITE);
+      Status                         = EncryptVariable (NewVarInfo);
+      if (!EFI_ERROR (Status)) {
+        //
+        // Update new data size in variable header.
+        //
+        SET_VARIABLE_DATA_SIZE (NewVarInfo, NewVarInfo->CipherDataSize);
+      } else if (Status != EFI_UNSUPPORTED) {
+        ASSERT (FALSE);
+        return Status;
+      }
+    }
+
+    if (Status == EFI_UNSUPPORTED) {
+      NewVarInfo->CipherData     = NewVarInfo->Header.Data;
+      NewVarInfo->CipherDataSize = (UINT32)NewVarInfo->Header.DataSize;
+      NewVarInfo->PlainData      = NULL;
+      NewVarInfo->PlainDataSize  = 0;
+    }
+  } else {
+    NewVarInfo->CipherData     = NULL;
+    NewVarInfo->CipherDataSize = 0;
+    NewVarInfo->PlainData      = NULL;
+    NewVarInfo->PlainDataSize  = 0;
+  }
+
+  if (NewVarDig->CacheIndex != 0) {
+    //
+    // Update the cached copy.
+    //
+    ZeroMem ((VOID *)&CachedVarInfo, sizeof (CachedVarInfo));
+    CachedVarInfo.Buffer     = GET_BUFR (NewVarDig->CacheIndex);
+    CachedVarInfo.StoreIndex = VAR_INDEX_INVALID;
+    CachedVarInfo.Flags.Auth = NewVarInfo->Flags.Auth;
+
+    Status = GET_CNTX (Global)->GetVariableInfo (&CachedVarInfo);
+    ASSERT_EFI_ERROR (Status);
+
+    if ((CachedVarInfo.Header.DataSize != 0) && (NewVarInfo->CipherDataSize > CachedVarInfo.Header.DataSize)) {
+      //
+      // allocate new VarInfo buffer that is of greater CipherDataSize
+      //
+      VarSize  =  VARIABLE_HEADER_SIZE (NewVarDig->Flags.Auth);
+      VarSize += NewVarInfo->Header.NameSize + GET_PAD_SIZE (NewVarInfo->Header.NameSize);
+      VarSize += NewVarInfo->CipherDataSize + GET_PAD_SIZE (NewVarInfo->CipherDataSize);
+      VarSize  = HEADER_ALIGN (VarSize);
+      Buffer   = AllocateZeroPool (VarSize);
+      if (Buffer != NULL) {
+        VarSize  =  VARIABLE_HEADER_SIZE (NewVarDig->Flags.Auth);
+        VarSize += CachedVarInfo.Header.NameSize + GET_PAD_SIZE (CachedVarInfo.Header.NameSize);
+        VarSize += CachedVarInfo.Header.DataSize + GET_PAD_SIZE (CachedVarInfo.DataSize);
+        VarSize  = HEADER_ALIGN (VarSize);
+
+        CopyMem (
+          Buffer,
+          CachedVarInfo.Buffer,
+          VarSize
+          );
+
+        FreePool (CachedVarInfo.Buffer);
+
+        //
+        // Update the cached copy.
+        //
+        ZeroMem ((VOID *)&CachedVarInfo, sizeof (CachedVarInfo));
+        CachedVarInfo.Buffer     = Buffer;
+        CachedVarInfo.StoreIndex = VAR_INDEX_INVALID;
+        CachedVarInfo.Flags.Auth = NewVarInfo->Flags.Auth;
+        Status                   = GET_CNTX (Global)->GetVariableInfo (&CachedVarInfo);
+        ASSERT_EFI_ERROR (Status);
+        NewVarDig->CacheIndex = (EFI_PHYSICAL_ADDRESS)(UINTN)Buffer;
+      }
+    }
+
+    CopyMem (
+      CachedVarInfo.Header.Data,
+      NewVarInfo->CipherData,
+      NewVarInfo->CipherDataSize
+      );
+    SET_VARIABLE_DATA_SIZE (&CachedVarInfo, NewVarInfo->CipherDataSize);
+
+    NewVarDig->State    = VAR_ADDED;
+    NewVarDig->DataSize = NewVarInfo->CipherDataSize;
+
+    if (NewVarInfo->PlainDataSize > 0) {
+      NewVarDig->PlainDataSize = NewVarInfo->PlainDataSize;
+    } else {
+      NewVarDig->PlainDataSize = NewVarDig->DataSize;
+    }
+
+    //
+    // (Re-)Calculate the hash of the variable.
+    //
+    if (NewVarDig->Flags.Protected) {
+      GetVariableDigest (Global, NewVarInfo, VAR_DIG_VALUE (NewVarDig));
+    }
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+
+  Fix state of MetaDataHmacVar on NV variable storage, if there's failure at
+  last boot during updating variable.
+
+  This must be done before the first writing of variable in current boot,
+  including storage reclaim.
+
+  @retval EFI_UNSUPPORTED        Updating NV variable storage is not supported.
+  @retval EFI_OUT_OF_RESOURCES   Not enough resource to complete the operation.
+  @retval EFI_SUCCESS            Variable store was successfully updated.
+
+**/
+EFI_STATUS
+FixupHmacVariable (
+  VOID
+  )
+{
+  EFI_STATUS                     Status;
+  PROTECTED_VARIABLE_INFO        HmacVarInfo;
+  PROTECTED_VARIABLE_GLOBAL      *Global;
+  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn;
+  VARIABLE_DIGEST                *VarDig;
+  UINTN                          Index;
+
+  Status = GetProtectedVariableGlobal (&Global);
+  ASSERT_EFI_ERROR (Status);
+
+  if (Global->Flags.WriteReady) {
+    return EFI_SUCCESS;
+  }
+
+  ContextIn = GET_CNTX (Global);
+
+  //
+  // Delete invalid MetaDataHmacVar.
+  //
+  for (Index = 0; Index <= IndexHmacAdded; ++Index) {
+    if (Global->Unprotected[Index] == VAR_INDEX_INVALID) {
+      continue;
+    }
+
+    VarDig = VAR_DIG_PTR (Global->Unprotected[Index]);
+    if (VarDig->Flags.Valid) {
+      continue;
+    }
+
+    ZeroMem ((VOID *)&HmacVarInfo, sizeof (HmacVarInfo));
+    HmacVarInfo.StoreIndex = VarDig->StoreIndex;
+    HmacVarInfo.Flags.Auth = VarDig->Flags.Auth;
+
+    Status = ContextIn->GetVariableInfo (&HmacVarInfo);
+    if (!EFI_ERROR (Status) && (HmacVarInfo.Buffer != NULL)) {
+      HmacVarInfo.Buffer->State &= VAR_DELETED;
+      Status                     = ContextIn->UpdateVariableStore (
+                                                &HmacVarInfo,
+                                                OFFSET_OF (VARIABLE_HEADER, State),
+                                                sizeof (HmacVarInfo.Buffer->State),
+                                                &HmacVarInfo.Buffer->State
+                                                );
+      if (EFI_ERROR (Status)) {
+        ASSERT_EFI_ERROR (Status);
+        return Status;
+      }
+    }
+
+    //
+    // Release the resource and update related states.
+    //
+    VarDig->State &= VAR_DELETED;
+    RemoveVariableDigestNode (Global, VarDig, FALSE);
+    Global->Unprotected[Index] = VAR_INDEX_INVALID;
+  }
+
+  //
+  // There should be no MetaDataHmacVar if in variable storage recovery mode.
+  //
+  if (Global->Flags.RecoveryMode) {
+    ASSERT (Global->Unprotected[IndexHmacAdded] == VAR_INDEX_INVALID);
+    ASSERT (Global->Unprotected[IndexHmacInDel] == VAR_INDEX_INVALID);
+  }
+
+  Global->Flags.WriteReady = TRUE;
+
+  return EFI_SUCCESS;
+}
+
+/**
+
+  Prepare for variable update.
+
+  This is needed only once during current boot to mitigate replay attack. Its
+  major job is to advance RPMC (Replay Protected Monotonic Counter).
+
+  @retval EFI_SUCCESS             Variable is ready to update hereafter.
+  @retval EFI_UNSUPPORTED         Updating variable is not supported.
+  @retval EFI_DEVICE_ERROR        Error in advancing RPMC.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibWriteInit (
+  VOID
+  )
+{
+  EFI_STATUS                     Status;
+  PROTECTED_VARIABLE_GLOBAL      *Global;
+  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn;
+  PROTECTED_VARIABLE_INFO        VarInfo;
+
+  (VOID)GetProtectedVariableGlobal (&Global);
+  ContextIn = GET_CNTX (Global);
+
+  //
+  // HmacVarInfo should be here
+  //
+  if (Global->Flags.RecoveryMode) {
+    //
+    // Flush default variables to variable storage if in variable recovery mode.
+    //
+    Status = ContextIn->UpdateVariableStore (NULL, 0, (UINT32)-1, NULL);
+    if (EFI_ERROR (Status)) {
+      ASSERT_EFI_ERROR (Status);
+      return Status;
+    }
+  } else {
+    //
+    // RPMC1 is going to be one step ahead of RPMC2 here, in order to
+    // refresh the MetaDataHmacVar in each boot before writing any other
+    // variables.
+    //
+    Status = IncrementMonotonicCounter (RPMC_COUNTER_1);
+    ASSERT_EFI_ERROR (Status);
+
+    ContextIn = GET_CNTX (Global);
+
+    //
+    // Fix any wrong MetaDataHmacVar information before adding new one.
+    //
+    Status = FixupHmacVariable ();
+    if (EFI_ERROR (Status)) {
+      ASSERT_EFI_ERROR (Status);
+      return Status;
+    }
+
+    if (!Global->Flags.WriteReady) {
+      return EFI_NOT_READY;
+    }
+
+    //
+    // Refresh MetaDataHmacVar with RPMC2 by 1 in each boot before any variable
+    // update,  by deleting (attr == 0 && datasize == 0) the old one.
+    //
+    ZeroMem (&VarInfo, sizeof (PROTECTED_VARIABLE_INFO));  // Zero attr & datasize
+
+    VarInfo.Flags.Auth          = Global->Flags.Auth;
+    VarInfo.Header.VariableName = METADATA_HMAC_VARIABLE_NAME;
+    VarInfo.Header.NameSize     = METADATA_HMAC_VARIABLE_NAME_SIZE;
+    VarInfo.Header.VendorGuid   = &METADATA_HMAC_VARIABLE_GUID;
+
+    //
+    // Pretend to delete MetaDataHmacVar.
+    //
+    Status = ContextIn->UpdateVariable (&VarInfo.Header);
+    if (EFI_ERROR (Status)) {
+      ASSERT_EFI_ERROR (Status);
+      return Status;
+    }
+  }
+
+  mProtectedVariableGlobal.Flags.WriteInit = TRUE;
+
+  return EFI_SUCCESS;
+}
+
+/**
+
+  Update a variable with protection provided by this library.
+
+  If variable encryption is employed, the new variable data will be encrypted
+  before being written to NV variable storage.
+
+  A special variable, called "MetaDataHmacVar", will always be updated along
+  with variable being updated to reflect the changes (HMAC value) of all
+  protected valid variables. The only exceptions, currently, is variable
+  variable "VarErrorLog".
+
+  The buffer passed by NewVariable must be double of maximum variable size,
+  which allows to pass the "MetaDataHmacVar" back to caller along with encrypted
+  new variable data, if any. This can make sure the new variable data and
+  "MetaDataHmacVar" can be written at almost the same time to reduce the chance
+  of compromising the integrity.
+
+  If *NewVariableSize is zero, it means to delete variable passed by CurrVariable
+  and/or CurrVariableInDel. "MetaDataHmacVar" will be updated as well in such
+  case because of less variables in storage. NewVariable should be always passed
+  in to convey new "MetaDataHmacVar" back.
+
+  @param[in,out]  CurrVariable        Variable to be updated. It's NULL if
+                                      adding a new variable.
+  @param[in]      CurrVariableInDel   In-delete-transition copy of updating variable.
+  @param[in,out]  NewVariable         Buffer of new variable data.
+                                      Buffer of "MetaDataHmacVar" and new
+                                      variable (encrypted).
+  @param[in,out]  NewVariableSize     Size of NewVariable.
+                                      Size of (encrypted) NewVariable and
+                                      "MetaDataHmacVar".
+
+  @retval EFI_SUCCESS             The variable is updated with protection successfully.
+  @retval EFI_INVALID_PARAMETER   NewVariable is NULL.
+  @retval EFI_NOT_FOUND           Information missing to finish the operation.
+  @retval EFI_ABORTED             Failed to encrypt variable or calculate HMAC.
+  @retval EFI_NOT_READY           The RPMC device is not yet initialized.
+  @retval EFI_DEVICE_ERROR        The RPMC device has error in updating.
+  @retval EFI_ACCESS_DENIED       The given variable is not allowed to update.
+                                  Currently this only happens on updating
+                                  "MetaDataHmacVar" from code outside of this
+                                  library.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibUpdate (
+  IN  OUT VARIABLE_HEADER  *CurrVariable,
+  IN      VARIABLE_HEADER  *CurrVariableInDel,
+  IN  OUT VARIABLE_HEADER  *NewVariable,
+  IN  OUT UINTN            *NewVariableSize
+  )
+{
+  EFI_STATUS                     Status;
+  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn;
+  PROTECTED_VARIABLE_GLOBAL      *Global;
+  PROTECTED_VARIABLE_INFO        VarInfo;
+  VARIABLE_DIGEST                *VarDig;
+  VARIABLE_DIGEST                *CurrVarDig;
+  VARIABLE_DIGEST                *NewVarDig;
+  PROTECTED_VARIABLE_INFO        NewVarInfo;
+  PROTECTED_VARIABLE_INFO        NewHmacVarInfo;
+  UINTN                          VarSize;
+  UINT64                         UnprotectedVarIndex;
+
+  //
+  // Advance RPMC
+  //
+  Status = IncrementMonotonicCounter (RPMC_COUNTER_1);
+  ASSERT_EFI_ERROR (Status);
+
+  //
+  // Buffer for new variable is always needed, even this function is called to
+  // delete an existing one, because we need to pass the MetaDataHmacVar back
+  // which will be updated upon each variable addition or deletion.
+  //
+  if ((NewVariable == NULL) || (NewVariableSize == NULL)) {
+    ASSERT (NewVariable != NULL);
+    ASSERT (NewVariableSize != NULL);
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Status = GetProtectedVariableGlobal (&Global);
+  ASSERT_EFI_ERROR (Status);
+  ContextIn = GET_CNTX (Global);
+
+  if (!Global->Flags.WriteReady && !Global->Flags.WriteInit) {
+    return EFI_NOT_READY;
+  }
+
+  VarSize             = 0;
+  CurrVarDig          = NULL;
+  NewVarDig           = NULL;
+  UnprotectedVarIndex = VAR_INDEX_INVALID;
+
+  //
+  // Check existing copy of the same variable.
+  //
+  if (CurrVariable != NULL) {
+    //
+    // Find local cached copy, if possible.
+    //
+    ZeroMem (&VarInfo, sizeof (VarInfo));
+    VarInfo.Buffer     = CurrVariable;
+    VarInfo.StoreIndex = VAR_INDEX_INVALID;
+    VarInfo.Flags.Auth = Global->Flags.Auth;
+
+    Status = ContextIn->GetVariableInfo (&VarInfo); // Retrieve the name/guid
+    ASSERT_EFI_ERROR (Status);
+
+    UnprotectedVarIndex = CheckKnownUnprotectedVariable (Global, &VarInfo);
+    if (UnprotectedVarIndex < UnprotectedVarIndexMax) {
+      CurrVarDig = VAR_DIG_PTR (Global->Unprotected[UnprotectedVarIndex]);
+    } else {
+      CurrVarDig = FindVariableInternal (Global, &VarInfo, FALSE);
+    }
+
+    ASSERT (CurrVarDig != NULL);
+    CurrVarDig->State &= VAR_DELETED;
+  }
+
+  //
+  // The old copy of the variable might haven't been deleted completely.
+  //
+  if (CurrVariableInDel != NULL) {
+    //
+    // Find local cached copy, if possible.
+    //
+    ZeroMem (&VarInfo, sizeof (VarInfo));
+    VarInfo.Buffer     = CurrVariableInDel;
+    VarInfo.StoreIndex = VAR_INDEX_INVALID;
+    VarInfo.Flags.Auth = Global->Flags.Auth;
+
+    Status = ContextIn->GetVariableInfo (&VarInfo); // Retrieve the name/guid
+    ASSERT_EFI_ERROR (Status);
+
+    if (UnprotectedVarIndex == VAR_INDEX_INVALID) {
+      UnprotectedVarIndex = CheckKnownUnprotectedVariable (Global, &VarInfo);
+    }
+
+    if (UnprotectedVarIndex < UnprotectedVarIndexMax) {
+      VarDig = VAR_DIG_PTR (Global->Unprotected[UnprotectedVarIndex]);
+    } else {
+      VarDig = FindVariableInternal (Global, &VarInfo, FALSE);
+    }
+
+    if ((VarDig != NULL) && (VAR_DIG_ADR (VarDig) != VAR_INDEX_INVALID)) {
+      VarDig->State &= VAR_DELETED;
+
+      //
+      // Just need one node for the same variable. So remove the one
+      // in-del-transition.
+      //
+      if ((CurrVarDig != NULL) && (VarDig != CurrVarDig)) {
+        RemoveVariableDigestNode (Global, VarDig, TRUE);
+      } else {
+        CurrVarDig = VarDig;  // Reuse the one in-del-transition.
+      }
+    }
+  }
+
+  //
+  // New data of the variable or new variable to be added.
+  //
+  if (NewVariable != NULL) {
+    //
+    // Completely new variable?
+    //
+    if (UnprotectedVarIndex == VAR_INDEX_INVALID) {
+      ZeroMem (&VarInfo, sizeof (VarInfo));
+      VarInfo.Buffer     = NewVariable;
+      VarInfo.StoreIndex = VAR_INDEX_INVALID;
+      VarInfo.Flags.Auth = Global->Flags.Auth;
+
+      Status = ContextIn->GetVariableInfo (&VarInfo); // Retrieve the name/guid
+      ASSERT_EFI_ERROR (Status);
+
+      UnprotectedVarIndex = CheckKnownUnprotectedVariable (Global, &VarInfo);
+    }
+  }
+
+  //
+  // Reserve space for MetaDataHmacVar (before the new variable so
+  // that it can be written first).
+  //
+  ZeroMem (&NewVarInfo, sizeof (NewVarInfo));
+  ZeroMem (&NewHmacVarInfo, sizeof (NewHmacVarInfo));
+
+  //
+  // Put the MetaDataHmacVar at the beginning of buffer.
+  //
+  NewHmacVarInfo.Buffer = NewVariable;
+
+  if (*NewVariableSize == 0) {
+    //
+    // Delete variable (but not MetaDataHmacVar)
+    //
+    if (  (UnprotectedVarIndex != IndexHmacAdded)
+       && (UnprotectedVarIndex != IndexHmacInDel))
+    {
+      RemoveVariableDigestNode (Global, CurrVarDig, TRUE);
+    }
+
+    NewVarInfo.Buffer = NULL;
+  } else if (UnprotectedVarIndex >= IndexPlatformVar) {
+    //
+    // Add/update variable. Move new variable data to be after MetaDataHmacVar.
+    //
+    // TRICK: New MetaDataHmacVar will be put at the beginning of buffer
+    //        for new variable so that they can be written into non-volatile
+    //        variable storage in one call. This can avoid writing one variable
+    //        (NewHmacVarInfo) in the middle of writing another variable
+    //        (NewVarInfo), which will need two calls and introduce extra
+    //        complexities (from temp variable buffer reservation to variable
+    //        space reclaim, etc.) in current implementation of variable
+    //        services. The caller must make sure there's enough space in
+    //        variable buffer (i.e. at least 2 * MaxVariableSize).
+    //
+    NewVarInfo.Buffer = (VARIABLE_HEADER *)((UINTN)NewVariable
+                                            + GetMetaDataHmacVarSize (Global->Flags.Auth));
+    CopyMem ((VOID *)NewVarInfo.Buffer, (VOID *)NewVariable, *NewVariableSize);
+
+    NewVarInfo.StoreIndex = VAR_INDEX_INVALID;   // Skip offset calculation (it's new one)
+    NewVarInfo.Flags.Auth = Global->Flags.Auth;
+
+    Status = ContextIn->GetVariableInfo (&NewVarInfo);
+    ASSERT_EFI_ERROR (Status);
+
+    if (CurrVarDig != NULL) {
+      //
+      // Update existing variable. Re-use the node.
+      //
+      NewVarDig = CurrVarDig;
+    } else {
+      //
+      // Add new variable.
+      //
+      NewVarDig = CreateVariableDigestNode (
+                    NewVarInfo.Header.VariableName,
+                    NewVarInfo.Header.VendorGuid,
+                    (UINT16)NewVarInfo.Header.NameSize,
+                    (UINT32)NewVarInfo.Header.DataSize,
+                    NewVarInfo.Flags.Auth,
+                    Global
+                    );
+      if (NewVarDig == NULL) {
+        return EFI_OUT_OF_RESOURCES;
+      }
+
+      NewVarDig->Attributes = NewVarInfo.Header.Attributes;
+      if (UnprotectedVarIndex < UnprotectedVarIndexMax) {
+        NewVarDig->Flags.Protected               = FALSE;
+        NewVarDig->Flags.Encrypted               = FALSE;
+        Global->Unprotected[UnprotectedVarIndex] = VAR_DIG_ADR (NewVarDig);
+      }
+
+      //
+      // copy new variable to CacheIndex
+      //
+      VarSize  =  VARIABLE_HEADER_SIZE (NewVarInfo.Flags.Auth);
+      VarSize += NewVarInfo.Header.NameSize + GET_PAD_SIZE (NewVarInfo.Header.NameSize);
+      VarSize += NewVarInfo.Header.DataSize + GET_PAD_SIZE (NewVarInfo.Header.DataSize);
+      VarSize  = HEADER_ALIGN (VarSize);
+      CopyMem (GET_BUFR (NewVarDig->CacheIndex), GET_BUFR (NewVarInfo.Buffer), VarSize);
+      InsertVariableDigestNode (Global, NewVarDig, NULL);
+    }
+  }
+
+  if (  (UnprotectedVarIndex == IndexHmacAdded)
+     || (UnprotectedVarIndex == IndexHmacInDel))
+  {
+    //
+    // MetaDataHmacVar should be managed only by this library. It's not
+    // supposed to be updated by external users of variable service. The only
+    // exception is that deleting it (not really delete but refresh the HMAC
+    // value against RPMC+1) is allowed before WriteInit, as a way to always
+    // increment RPMC once in current boot before any variable updates.
+    //
+    if ((NewVarInfo.Buffer != NULL) || Global->Flags.WriteInit) {
+      return EFI_ACCESS_DENIED;
+    }
+  } else {
+    //
+    // Do encryption, if enabled.
+    //
+    if ((NewVarDig != NULL) && (NewVarInfo.Buffer != NULL)) {
+      Status = UpdateVariableInternal (Global, &NewVarInfo, NewVarDig);
+      if (EFI_ERROR (Status)) {
+        ASSERT_EFI_ERROR (Status);
+        return Status;
+      }
+    }
+  }
+
+  //
+  // Refresh MetaDataHmacVar.
+  //
+  Status = RefreshVariableMetadataHmac (Global, NULL, &NewHmacVarInfo);
+  if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+    return Status;
+  }
+
+  //
+  // Return size for both MetaDataHmacVar and added/updated one.
+  //
+  VarSize          = VARIABLE_SIZE (&NewHmacVarInfo);
+  *NewVariableSize = HEADER_ALIGN (VarSize);
+  if (NewVarInfo.Buffer != NULL) {
+    VarSize = VARIABLE_SIZE (&NewVarInfo);
+    VarSize = HEADER_ALIGN (VarSize);
+
+    if (VarSize > GET_CNTX (Global)->MaxVariableSize) {
+      return EFI_BAD_BUFFER_SIZE;
+    }
+
+    *NewVariableSize += VarSize;
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+
+  Finalize a variable updating after it's written to NV variable storage
+  successfully.
+
+  This usually includes works like increasing RPMC, synchronizing local cache,
+  updating new position of "MetaDataHmacVar", deleting old copy of "MetaDataHmacVar"
+  completely, etc.
+
+  @param[in]      NewVariable       Buffer of new variables and MetaDataHmacVar.
+  @param[in]      VariableSize      Size of buffer pointed by NewVariable.
+  @param[in]      StoreIndex        StoreIndex to NV variable storage from where the new
+                                    variable and MetaDataHmacVar have been written.
+
+  @retval EFI_SUCCESS         No problem in winding up the variable write operation.
+  @retval Others              Failed to updating state of old copy of updated
+                              variable, or failed to increase RPMC, etc.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibWriteFinal (
+  IN  VARIABLE_HEADER  *NewVariable,
+  IN  UINTN            VariableSize,
+  IN  UINT64           StoreIndex
+  )
+{
+  EFI_STATUS                     Status;
+  PROTECTED_VARIABLE_INFO        VarInfo;
+  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn;
+  PROTECTED_VARIABLE_GLOBAL      *Global;
+  UNPROTECTED_VARIABLE_INDEX     Index;
+  VARIABLE_DIGEST                *VarDig;
+  VOID                           *Buffer;
+  UINTN                          VarSize;
+  UINTN                          NewVarSize;
+
+  Status = GetProtectedVariableGlobal (&Global);
+  ASSERT_EFI_ERROR (Status);
+  ContextIn = GET_CNTX (Global);
+
+  ZeroMem ((VOID *)&VarInfo, sizeof (VarInfo));
+  VarInfo.Buffer     = NewVariable;
+  VarInfo.StoreIndex = VAR_INDEX_INVALID;
+  VarInfo.Flags.Auth = Global->Flags.Auth;
+
+  Status = ContextIn->GetVariableInfo (&VarInfo);
+  ASSERT_EFI_ERROR (Status);
+
+  Index = CheckKnownUnprotectedVariable (Global, &VarInfo);
+  if (Index < UnprotectedVarIndexMax) {
+    VarDig = VAR_DIG_PTR (Global->Unprotected[Index]);
+  } else {
+    VarDig = FindVariableInternal (Global, &VarInfo, FALSE);
+  }
+
+  if (Index == IndexHmacAdded) {
+    //
+    // Advance the RPMC to let it match new MetaDataHmacVar.
+    //
+    Status = IncrementMonotonicCounter (RPMC_COUNTER_2);
+    ASSERT_EFI_ERROR (Status);
+
+    if ((VarDig->StoreIndex != VAR_INDEX_INVALID) && (VarDig->State != VAR_ADDED)) {
+      ZeroMem ((VOID *)&VarInfo, sizeof (VarInfo));
+      VarInfo.StoreIndex = VarDig->StoreIndex;  // Still point to old copy
+      VarInfo.Flags.Auth = Global->Flags.Auth;
+
+      //
+      // Delete variable completely.
+      //
+      Status = ContextIn->GetVariableInfo (&VarInfo);
+      ASSERT_EFI_ERROR (Status);
+
+      if (  (VarInfo.Buffer->State == VAR_ADDED)
+         || (VarInfo.Buffer->State == (VAR_ADDED & VAR_IN_DELETED_TRANSITION)))
+      {
+        VarInfo.Buffer->State &= VAR_DELETED;
+        Status                 = ContextIn->UpdateVariableStore (
+                                              &VarInfo,
+                                              OFFSET_OF (VARIABLE_HEADER, State),
+                                              sizeof (VarInfo.Buffer->State),
+                                              &VarInfo.Buffer->State
+                                              );
+        if (EFI_ERROR (Status)) {
+          ASSERT_EFI_ERROR (Status);
+          return Status;
+        }
+      }
+    }
+  }
+
+  VarDig->StoreIndex = StoreIndex;
+  VarDig->State      = VAR_ADDED;
+
+  ZeroMem ((VOID *)&VarInfo, sizeof (VarInfo));
+  VarInfo.Buffer     = NULL;
+  VarInfo.StoreIndex = VarDig->StoreIndex;
+  VarInfo.Flags.Auth = Global->Flags.Auth;
+  Status             = ContextIn->GetVariableInfo (&VarInfo);
+
+  //
+  // Check if cache pool need re-allocation due to variable size increase
+  //
+  VarSize  =  VARIABLE_HEADER_SIZE (VarDig->Flags.Auth);
+  VarSize += VarDig->NameSize + GET_PAD_SIZE (VarDig->NameSize);
+  VarSize += VarDig->DataSize + GET_PAD_SIZE (VarDig->DataSize);
+  VarSize  = HEADER_ALIGN (VarSize);
+
+  NewVarSize  =  VARIABLE_HEADER_SIZE (VarInfo.Flags.Auth);
+  NewVarSize += VarInfo.Header.NameSize + GET_PAD_SIZE (VarInfo.Header.NameSize);
+  NewVarSize += VarInfo.Header.DataSize + GET_PAD_SIZE (VarInfo.Header.DataSize);
+  NewVarSize  = HEADER_ALIGN (NewVarSize);
+
+  if (VarSize < NewVarSize) {
+    if (VarDig->Flags.Freeable == TRUE) {
+      FreePool (GET_BUFR (VarDig->CacheIndex));
+    }
+
+    Buffer = AllocatePool (NewVarSize);
+    if (Buffer != NULL) {
+      VarDig->CacheIndex = (EFI_PHYSICAL_ADDRESS)(UINTN)Buffer;
+    } else {
+      ASSERT (FALSE);
+      return EFI_ABORTED;
+    }
+  }
+
+  //
+  // Update cached copy.
+  //
+  CopyMem (GET_BUFR (VarDig->CacheIndex), NewVariable, NewVarSize);
+
+  //
+  // Check if there is consecutive variable as part of the write or
+  // is it just the MetaDataHmacVar variable
+  //
+  if (NewVarSize < VariableSize) {
+    //
+    // Advance to consecutive Variable
+    //
+    NewVariable = GET_BUFR (GET_ADRS (NewVariable) + NewVarSize);
+
+    //
+    // Update the StoreIndex of consecutive Variable
+    //
+    ZeroMem ((VOID *)&VarInfo, sizeof (VarInfo));
+    VarInfo.Buffer     = NULL;
+    VarInfo.StoreIndex = VarDig->StoreIndex;
+    VarInfo.Flags.Auth = Global->Flags.Auth;
+    Status             = ContextIn->GetNextVariableInfo (&VarInfo);
+    StoreIndex         = VarInfo.StoreIndex;
+
+    //
+    // The new StoreIndex does not exist in the variable digest.
+    // It is yet to be updated.
+    // Therefore, find variable by Name & Guid instead.
+    //
+    VarInfo.StoreIndex = VAR_INDEX_INVALID;
+    VarDig             = FindVariableInternal (Global, &VarInfo, FALSE);
+
+    //
+    // Check if cache pool need re-allocation due to variable size increase
+    //
+    VarSize  =  VARIABLE_HEADER_SIZE (VarDig->Flags.Auth);
+    VarSize += VarDig->NameSize + GET_PAD_SIZE (VarDig->NameSize);
+    VarSize += VarDig->DataSize + GET_PAD_SIZE (VarDig->DataSize);
+    VarSize  = HEADER_ALIGN (VarSize);
+
+    NewVarSize  =  VARIABLE_HEADER_SIZE (VarInfo.Flags.Auth);
+    NewVarSize += VarInfo.Header.NameSize + GET_PAD_SIZE (VarInfo.Header.NameSize);
+    NewVarSize += VarInfo.Header.DataSize + GET_PAD_SIZE (VarInfo.Header.DataSize);
+    NewVarSize  = HEADER_ALIGN (NewVarSize);
+
+    if (VarSize < NewVarSize) {
+      if (VarDig->Flags.Freeable == TRUE) {
+        FreePool (GET_BUFR (VarDig->CacheIndex));
+      }
+
+      Buffer = AllocatePool (NewVarSize);
+      if (Buffer != NULL) {
+        VarDig->CacheIndex = (EFI_PHYSICAL_ADDRESS)(UINTN)Buffer;
+      } else {
+        ASSERT (FALSE);
+        return EFI_ABORTED;
+      }
+    }
+
+    //
+    // Update cached copy.
+    //
+    CopyMem (GET_BUFR (VarDig->CacheIndex), NewVariable, NewVarSize);
+    VarDig->StoreIndex = StoreIndex;
+  }
+
+  return Status;
+}
+
+/**
+  Refresh variable information changed by variable service.
+
+  @param[in]  Variable         Pointer to buffer of the updated variable.
+  @param[in]  VariableSize     Size of variable pointed by Variable.
+  @param[in]  StoreIndex       New index of the variable in store.
+  @param[in]  RefreshData      Flag to indicate if the variable has been updated.
+
+  @return EFI_SUCCESS     No error occurred in updating.
+  @return EFI_NOT_FOUND   The given variable was not found in
+                          ProtectedVariableLib.
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibRefresh (
+  IN  VARIABLE_HEADER  *Variable,
+  IN  UINTN            VariableSize,
+  IN  UINT64           StoreIndex,
+  IN  BOOLEAN          RefreshData
+  )
+{
+  EFI_STATUS                 Status;
+  PROTECTED_VARIABLE_INFO    VarInfo;
+  PROTECTED_VARIABLE_GLOBAL  *Global;
+  VARIABLE_DIGEST            *VarDig;
+
+  (VOID)GetProtectedVariableGlobal (&Global);
+
+  ZeroMem ((VOID *)&VarInfo, sizeof (VarInfo));
+  VarInfo.Buffer     = Variable;
+  VarInfo.StoreIndex = VAR_INDEX_INVALID;
+  VarInfo.Flags.Auth = Global->Flags.Auth;
+
+  Status = GET_CNTX (Global)->GetVariableInfo (&VarInfo);
+  ASSERT_EFI_ERROR (Status);
+
+  VarDig = FindVariableInternal (Global, &VarInfo, FALSE);
+  if (VarDig == NULL) {
+    ASSERT (VarDig != NULL);
+    return EFI_NOT_FOUND;
+  }
+
+  if (StoreIndex != VAR_INDEX_INVALID) {
+    VarDig->StoreIndex = StoreIndex;
+  }
+
+  if (RefreshData) {
+    if (VarDig->CacheIndex == VAR_INDEX_INVALID) {
+      VarDig->CacheIndex = (EFI_PHYSICAL_ADDRESS)(UINTN)
+                           AllocatePool (MAX_VARIABLE_SIZE);
+    }
+
+    CopyMem (GET_BUFR (VarDig->CacheIndex), Variable, VariableSize);
+  }
+
+  //
+  // Information should stay the same other than following ones.
+  //
+  VarDig->State    = VarInfo.Header.State;
+  VarDig->DataSize = (UINT32)VarInfo.Header.DataSize;
+
+  return EFI_SUCCESS;
+}
+
+/**
+
+  Determine if the variable is the HMAC variable
+
+  @param VariableName   Pointer to variable name.
+
+  @return TRUE      Variable is HMAC variable
+  @return FALSE     Variable is not HMAC variable
+
+**/
+BOOLEAN
+ProtectedVariableLibIsHmac (
+  IN CHAR16  *VariableName
+  )
+{
+  INTN  Result;
+
+  Result = StrnCmp (
+             METADATA_HMAC_VARIABLE_NAME,
+             VariableName,
+             METADATA_HMAC_VARIABLE_NAME_SIZE
+             );
+
+  if (Result == 0) {
+    return TRUE;
+  }
+
+  return FALSE;
+}
diff --git a/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmRuntime.c b/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmRuntime.c
new file mode 100644
index 000000000000..4591d1cd59e5
--- /dev/null
+++ b/SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmRuntime.c
@@ -0,0 +1,233 @@
+/** @file
+  Implemention of ProtectedVariableLib for BootService/Runtime use cases.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <PiDxe.h>
+#include <Uefi.h>
+
+#include "Library/MemoryAllocationLib.h"
+#include "Library/UefiBootServicesTableLib.h"
+#include "Library/UefiRuntimeLib.h"
+#include "ProtectedVariableInternal.h"
+
+EFI_EVENT  mVaChangeEvent = NULL;
+
+PROTECTED_VARIABLE_CONTEXT_IN  mRtVariableContextIn = {
+  PROTECTED_VARIABLE_CONTEXT_IN_STRUCT_VERSION,
+  sizeof (PROTECTED_VARIABLE_CONTEXT_IN),
+  0,
+  FromRuntimeModule,
+  NULL,
+  NULL,
+  NULL,
+  NULL,
+  NULL
+};
+
+PROTECTED_VARIABLE_GLOBAL  mRtProtectedVariableGlobal = {
+  PROTECTED_VARIABLE_CONTEXT_OUT_STRUCT_VERSION,
+  sizeof (PROTECTED_VARIABLE_GLOBAL),
+  { 0 },
+  { 0 },
+  0,
+  0,
+  0,
+  0,
+  0,
+  0,
+  { 0,                                          0,  0 },
+  0,
+  0,
+  { 0,                                          0,  0, 0, 0, 0}
+};
+
+/**
+
+  Get global data structure used to process protected variable.
+
+  @param[out]   Global      Pointer to global configuration data.
+
+  @retval EFI_SUCCESS         Get requested structure successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+GetProtectedVariableGlobal (
+  OUT PROTECTED_VARIABLE_GLOBAL  **Global OPTIONAL
+  )
+{
+  if (Global != NULL) {
+    mRtProtectedVariableGlobal.ContextIn = GET_ADRS (&mRtVariableContextIn);
+    *Global                              = &mRtProtectedVariableGlobal;
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Notification function of EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE.
+
+  This is a notification function registered on EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE event.
+  It convers pointer to new virtual address.
+
+  @param[in]  Event        Event whose notification function is being invoked.
+  @param[in]  Context      Pointer to the notification function's context.
+
+**/
+VOID
+EFIAPI
+VirtualAddressChangeEvent (
+  IN EFI_EVENT  Event,
+  IN VOID       *Context
+  )
+{
+  if (mRtVariableContextIn.FindVariableSmm != NULL) {
+    EfiConvertPointer (0x0, (VOID **)&mRtVariableContextIn.FindVariableSmm);
+  }
+
+  if (mRtVariableContextIn.GetVariableInfo != NULL) {
+    EfiConvertPointer (0x0, (VOID **)&mRtVariableContextIn.GetVariableInfo);
+  }
+
+  if (mRtVariableContextIn.GetNextVariableInfo != NULL) {
+    EfiConvertPointer (0x0, (VOID **)&mRtVariableContextIn.GetNextVariableInfo);
+  }
+
+  if (mRtVariableContextIn.UpdateVariableStore != NULL) {
+    EfiConvertPointer (0x0, (VOID **)&mRtVariableContextIn.UpdateVariableStore);
+  }
+
+  EfiConvertPointer (0x0, (VOID **)&mRtVariableContextIn);
+  if (mRtProtectedVariableGlobal.VariableCache != 0) {
+    EfiConvertPointer (0x0, (VOID **)&mRtProtectedVariableGlobal.VariableCache);
+  }
+
+  EfiConvertPointer (0x0, (VOID **)&mRtProtectedVariableGlobal);
+}
+
+/**
+
+  Initialization for protected variable services.
+
+  If this initialization failed upon any error, the whole variable services
+  should not be used.  A system reset might be needed to re-construct NV
+  variable storage to be the default state.
+
+  @param[in]  ContextIn   Pointer to variable service context needed by
+                          protected variable.
+
+  @retval EFI_SUCCESS               Protected variable services are ready.
+  @retval EFI_INVALID_PARAMETER     If ContextIn == NULL or something missing or
+                                    mismatching in the content in ContextIn.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibInitialize (
+  IN  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn
+  )
+{
+  if (  (ContextIn == NULL)
+     || (ContextIn->StructVersion != PROTECTED_VARIABLE_CONTEXT_IN_STRUCT_VERSION)
+     || (ContextIn->FindVariableSmm == NULL)
+     || (ContextIn->GetVariableInfo == NULL))
+  {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  CopyMem (&mRtVariableContextIn, ContextIn, sizeof (mRtVariableContextIn));
+
+  //
+  // Register the event to convert the pointer for runtime.
+  //
+  gBS->CreateEventEx (
+         EVT_NOTIFY_SIGNAL,
+         TPL_NOTIFY,
+         VirtualAddressChangeEvent,
+         NULL,
+         &gEfiEventVirtualAddressChangeGuid,
+         &mVaChangeEvent
+         );
+
+  return EFI_SUCCESS;
+}
+
+/**
+
+  Prepare for variable update.
+
+  Not supported in DXE phase.
+
+  @retval EFI_UNSUPPORTED         Updating variable is not supported.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibWriteInit (
+  VOID
+  )
+{
+  ASSERT (FALSE);
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Update a variable with protection provided by this library.
+
+  Not supported in DXE phase.
+
+  @param[in,out]  CurrVariable        Variable to be updated. It's NULL if
+                                      adding a new variable.
+  @param[in]      CurrVariableInDel   In-delete-transition copy of updating variable.
+  @param[in,out]  NewVariable         Buffer of new variable data or
+                                      Buffer of "MetaDataHmacVar" and new variable (encrypted).
+  @param[in,out]  NewVariableSize     Size of NewVariable or
+                                      Size of (encrypted) NewVariable and "MetaDataHmacVar".
+
+  @retval EFI_UNSUPPORTED             Not support updating variable.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibUpdate (
+  IN  OUT VARIABLE_HEADER  *CurrVariable,
+  IN      VARIABLE_HEADER  *CurrVariableInDel,
+  IN  OUT VARIABLE_HEADER  *NewVariable,
+  IN  OUT UINTN            *NewVariableSize
+  )
+{
+  ASSERT (FALSE);
+  return EFI_UNSUPPORTED;
+}
+
+/**
+
+  Finalize a variable updating after it's written to NV variable storage
+  successfully.
+
+  (Not supported for BootService/Runtime use cases.)
+
+  @param[in]      NewVariable       Buffer of new variables and MetaDataHmacVar.
+  @param[in]      VariableSize      Size of buffer pointed by NewVariable.
+  @param[in]      StoreIndex        StoreIndex to NV variable storage from where the new
+                                    variable and MetaDataHmacVar have been written.
+
+  @retval EFI_UNSUPPORTED           Not supported for BootService/Runtime use cases.
+
+**/
+EFI_STATUS
+EFIAPI
+ProtectedVariableLibWriteFinal (
+  IN  VARIABLE_HEADER  *NewVariable,
+  IN  UINTN            VariableSize,
+  IN  UINT64           StoreIndex
+  )
+{
+  ASSERT (FALSE);
+  return EFI_UNSUPPORTED;
+}
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 18/28] MdeModulePkg: Reference Null ProtectedVariableLib
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (16 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 17/28] SecurityPkg: Add Protected Variable Services Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-04-29 18:04 ` [Patch v2 19/28] SecurityPkg: Add references to new *.inf files Judah Vang
                   ` (11 subsequent siblings)
  29 siblings, 0 replies; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Liming Gao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Make reference to new Null ProtectVariableLib.
The null ProtectedVariableLib is used by default.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 MdeModulePkg/MdeModulePkg.dsc | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/MdeModulePkg/MdeModulePkg.dsc b/MdeModulePkg/MdeModulePkg.dsc
index b1d83461865e..6d9847c0cd34 100644
--- a/MdeModulePkg/MdeModulePkg.dsc
+++ b/MdeModulePkg/MdeModulePkg.dsc
@@ -2,7 +2,7 @@
 # EFI/PI Reference Module Package for All Architectures
 #
 # (C) Copyright 2014 Hewlett-Packard Development Company, L.P.<BR>
-# Copyright (c) 2007 - 2021, Intel Corporation. All rights reserved.<BR>
+# Copyright (c) 2007 - 2022, Intel Corporation. All rights reserved.<BR>
 # Copyright (c) Microsoft Corporation.
 #
 #    SPDX-License-Identifier: BSD-2-Clause-Patent
@@ -103,6 +103,7 @@ [LibraryClasses]
   DisplayUpdateProgressLib|MdeModulePkg/Library/DisplayUpdateProgressLibGraphics/DisplayUpdateProgressLibGraphics.inf
   VariablePolicyHelperLib|MdeModulePkg/Library/VariablePolicyHelperLib/VariablePolicyHelperLib.inf
   MmUnblockMemoryLib|MdePkg/Library/MmUnblockMemoryLib/MmUnblockMemoryLibNull.inf
+  ProtectedVariableLib|MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
 
 [LibraryClasses.EBC.PEIM]
   IoLib|MdePkg/Library/PeiIoLibCpuIo/PeiIoLibCpuIo.inf
@@ -316,6 +317,7 @@ [Components]
   MdeModulePkg/Library/PlatformBootManagerLibNull/PlatformBootManagerLibNull.inf
   MdeModulePkg/Library/BootLogoLib/BootLogoLib.inf
   MdeModulePkg/Library/TpmMeasurementLibNull/TpmMeasurementLibNull.inf
+  MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
   MdeModulePkg/Library/AuthVariableLibNull/AuthVariableLibNull.inf
   MdeModulePkg/Library/VariablePolicyLib/VariablePolicyLib.inf
   MdeModulePkg/Library/VariablePolicyLib/VariablePolicyLibRuntimeDxe.inf
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 19/28] SecurityPkg: Add references to new *.inf files
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (17 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 18/28] MdeModulePkg: Reference Null ProtectedVariableLib Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-04-29 18:04 ` [Patch v2 20/28] ArmVirtPkg: Add reference to ProtectedVariableNull Judah Vang
                   ` (10 subsequent siblings)
  29 siblings, 0 replies; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Jiewen Yao, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add references to the different *ProtectedVariableLib.inf.
Also add references to VariableKeyLibNull.inf,
EncryptionVariableLibNull.inf, ProtectedVariableNull.inf.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 SecurityPkg/SecurityPkg.dsc | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/SecurityPkg/SecurityPkg.dsc b/SecurityPkg/SecurityPkg.dsc
index 73a93c2285b1..6d8318c6e4bf 100644
--- a/SecurityPkg/SecurityPkg.dsc
+++ b/SecurityPkg/SecurityPkg.dsc
@@ -1,7 +1,7 @@
 ## @file
 #  Security Module Package for All Architectures.
 #
-# Copyright (c) 2009 - 2021, Intel Corporation. All rights reserved.<BR>
+# Copyright (c) 2009 - 2022, Intel Corporation. All rights reserved.<BR>
 # (C) Copyright 2015-2020 Hewlett Packard Enterprise Development LP<BR>
 # SPDX-License-Identifier: BSD-2-Clause-Patent
 #
@@ -66,8 +66,11 @@ [LibraryClasses]
   TcgStorageCoreLib|SecurityPkg/Library/TcgStorageCoreLib/TcgStorageCoreLib.inf
   TcgStorageOpalLib|SecurityPkg/Library/TcgStorageOpalLib/TcgStorageOpalLib.inf
   ResetSystemLib|MdeModulePkg/Library/BaseResetSystemLibNull/BaseResetSystemLibNull.inf
+
+  # These should be Null by default
   VariableKeyLib|SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.inf
   RpmcLib|SecurityPkg/Library/RpmcLibNull/RpmcLibNull.inf
+  EncryptionVariableLib|SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf
   TcgEventLogRecordLib|SecurityPkg/Library/TcgEventLogRecordLib/TcgEventLogRecordLib.inf
   MmUnblockMemoryLib|MdePkg/Library/MmUnblockMemoryLib/MmUnblockMemoryLibNull.inf
   SecureBootVariableLib|SecurityPkg/Library/SecureBootVariableLib/SecureBootVariableLib.inf
@@ -251,8 +254,16 @@ [Components]
   #
   # Variable Confidentiality & Integrity
   #
+  SecurityPkg/Library/ProtectedVariableLib/PeiProtectedVariableLib.inf
+  SecurityPkg/Library/ProtectedVariableLib/DxeProtectedVariableLib.inf
+  SecurityPkg/Library/ProtectedVariableLib/SmmProtectedVariableLib.inf
+  SecurityPkg/Library/ProtectedVariableLib/SmmRuntimeProtectedVariableLib.inf
+  SecurityPkg/Library/EncryptionVariableLib/EncryptionVariableLib.inf
+  SecurityPkg/Library/VariableKeyLib/VariableKeyLib.inf
+
   SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.inf
   SecurityPkg/Library/RpmcLibNull/RpmcLibNull.inf
+  SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf
 
   #
   # Other
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 20/28] ArmVirtPkg: Add reference to ProtectedVariableNull
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (18 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 19/28] SecurityPkg: Add references to new *.inf files Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-03  7:29   ` Ard Biesheuvel
  2022-04-29 18:04 ` [Patch v2 21/28] UefiPayloadPkg: Add ProtectedVariable reference Judah Vang
                   ` (9 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Ard Biesheuvel, Leif Lindholm, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Need reference to ProtectVariableNullLib otherwise build fails.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 ArmVirtPkg/ArmVirtQemu.dsc | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/ArmVirtPkg/ArmVirtQemu.dsc b/ArmVirtPkg/ArmVirtQemu.dsc
index aa0ce61630f7..cdebd94a9fce 100644
--- a/ArmVirtPkg/ArmVirtQemu.dsc
+++ b/ArmVirtPkg/ArmVirtQemu.dsc
@@ -1,7 +1,7 @@
 #
 #  Copyright (c) 2011-2015, ARM Limited. All rights reserved.
 #  Copyright (c) 2014, Linaro Limited. All rights reserved.
-#  Copyright (c) 2015 - 2020, Intel Corporation. All rights reserved.
+#  Copyright (c) 2015 - 2022, Intel Corporation. All rights reserved.
 #
 #  SPDX-License-Identifier: BSD-2-Clause-Patent
 #
@@ -81,6 +81,7 @@ [LibraryClasses.common]
   PciSegmentLib|MdePkg/Library/BasePciSegmentLibPci/BasePciSegmentLibPci.inf
   PciHostBridgeLib|OvmfPkg/Fdt/FdtPciHostBridgeLib/FdtPciHostBridgeLib.inf
   PciHostBridgeUtilityLib|OvmfPkg/Library/PciHostBridgeUtilityLib/PciHostBridgeUtilityLib.inf
+  ProtectedVariableLib|MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
 
 !if $(TPM2_ENABLE) == TRUE
   Tpm2CommandLib|SecurityPkg/Library/Tpm2CommandLib/Tpm2CommandLib.inf
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 21/28] UefiPayloadPkg: Add ProtectedVariable reference
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (19 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 20/28] ArmVirtPkg: Add reference to ProtectedVariableNull Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-04-29 21:03   ` Guo Dong
  2022-04-29 18:04 ` [Patch v2 22/28] EmulatorPkg: " Judah Vang
                   ` (8 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel
  Cc: Jian J Wang, Guo Dong, Ray Ni, Maurice Ma, Benjamin You,
	Sean Rhodes, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add reference for ProtectedVariableLib so build is successful.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Guo Dong <guo.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Maurice Ma <maurice.ma@intel.com>
Cc: Benjamin You <benjamin.you@intel.com>
Cc: Sean Rhodes <sean@starlabs.systems>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 UefiPayloadPkg/UefiPayloadPkg.dsc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/UefiPayloadPkg/UefiPayloadPkg.dsc b/UefiPayloadPkg/UefiPayloadPkg.dsc
index 17b30589e77c..fe835eed1bc7 100644
--- a/UefiPayloadPkg/UefiPayloadPkg.dsc
+++ b/UefiPayloadPkg/UefiPayloadPkg.dsc
@@ -263,9 +263,11 @@ [LibraryClasses]
   AuthVariableLib|MdeModulePkg/Library/AuthVariableLibNull/AuthVariableLibNull.inf
 !if $(VARIABLE_SUPPORT) == "EMU"
   TpmMeasurementLib|MdeModulePkg/Library/TpmMeasurementLibNull/TpmMeasurementLibNull.inf
+  ProtectedVariableLib|MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
 !elseif $(VARIABLE_SUPPORT) == "SPI"
   PlatformSecureLib|SecurityPkg/Library/PlatformSecureLibNull/PlatformSecureLibNull.inf
   TpmMeasurementLib|SecurityPkg/Library/DxeTpmMeasurementLib/DxeTpmMeasurementLib.inf
+  ProtectedVariableLib|SecurityPkg/Library/ProtectedVariableLib/DxeProtectedVariableLib.inf
   S3BootScriptLib|MdePkg/Library/BaseS3BootScriptLibNull/BaseS3BootScriptLibNull.inf
   MmUnblockMemoryLib|MdePkg/Library/MmUnblockMemoryLib/MmUnblockMemoryLibNull.inf
 !endif
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 22/28] EmulatorPkg: Add ProtectedVariable reference
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (20 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 21/28] UefiPayloadPkg: Add ProtectedVariable reference Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-04-29 18:04 ` [Patch v2 23/28] OvmfPkg: " Judah Vang
                   ` (7 subsequent siblings)
  29 siblings, 0 replies; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Andrew Fish, Ray Ni, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add reference to null ProtectedVariableLib.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Andrew Fish <afish@apple.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 EmulatorPkg/EmulatorPkg.dsc | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/EmulatorPkg/EmulatorPkg.dsc b/EmulatorPkg/EmulatorPkg.dsc
index 554c13ddb500..4a6d50390db7 100644
--- a/EmulatorPkg/EmulatorPkg.dsc
+++ b/EmulatorPkg/EmulatorPkg.dsc
@@ -4,7 +4,7 @@
 # The Emulation Platform can be used to debug individual modules, prior to creating
 # a real platform. This also provides an example for how an DSC is created.
 #
-# Copyright (c) 2006 - 2021, Intel Corporation. All rights reserved.<BR>
+# Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
 # Portions copyright (c) 2010 - 2011, Apple Inc. All rights reserved.<BR>
 # Copyright (c) Microsoft Corporation.
 #
@@ -119,6 +119,7 @@ [LibraryClasses]
   LockBoxLib|MdeModulePkg/Library/LockBoxNullLib/LockBoxNullLib.inf
   CpuExceptionHandlerLib|MdeModulePkg/Library/CpuExceptionHandlerLibNull/CpuExceptionHandlerLibNull.inf
   TpmMeasurementLib|MdeModulePkg/Library/TpmMeasurementLibNull/TpmMeasurementLibNull.inf
+  ProtectedVariableLib|MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
   VarCheckLib|MdeModulePkg/Library/VarCheckLib/VarCheckLib.inf
   VariablePolicyLib|MdeModulePkg/Library/VariablePolicyLib/VariablePolicyLibRuntimeDxe.inf
   VariablePolicyHelperLib|MdeModulePkg/Library/VariablePolicyHelperLib/VariablePolicyHelperLib.inf
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 23/28] OvmfPkg: Add ProtectedVariable reference
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (21 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 22/28] EmulatorPkg: " Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-04-29 18:04 ` [Patch v2 24/28] OvmfPkg: Add ProtectedVariableLib reference Judah Vang
                   ` (6 subsequent siblings)
  29 siblings, 0 replies; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel
  Cc: Jian J Wang, Ard Biesheuvel, Jiewen Yao, Jordan Justen,
	Gerd Hoffmann, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add reference to null ProtectedVariableLib.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 OvmfPkg/OvmfPkgIa32.dsc    | 1 +
 OvmfPkg/OvmfPkgIa32X64.dsc | 1 +
 OvmfPkg/OvmfPkgX64.dsc     | 1 +
 OvmfPkg/OvmfXen.dsc        | 3 ++-
 4 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/OvmfPkg/OvmfPkgIa32.dsc b/OvmfPkg/OvmfPkgIa32.dsc
index f02b371f7427..358ad991a2dc 100644
--- a/OvmfPkg/OvmfPkgIa32.dsc
+++ b/OvmfPkg/OvmfPkgIa32.dsc
@@ -178,6 +178,7 @@ [LibraryClasses]
   LoadLinuxLib|OvmfPkg/Library/LoadLinuxLib/LoadLinuxLib.inf
   MemEncryptSevLib|OvmfPkg/Library/BaseMemEncryptSevLib/DxeMemEncryptSevLib.inf
   MemEncryptTdxLib|OvmfPkg/Library/BaseMemEncryptTdxLib/BaseMemEncryptTdxLibNull.inf
+  ProtectedVariableLib|MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
 !if $(SMM_REQUIRE) == FALSE
   LockBoxLib|OvmfPkg/Library/LockBoxLib/LockBoxBaseLib.inf
 !endif
diff --git a/OvmfPkg/OvmfPkgIa32X64.dsc b/OvmfPkg/OvmfPkgIa32X64.dsc
index cb68e612bd35..7e46d53061b1 100644
--- a/OvmfPkg/OvmfPkgIa32X64.dsc
+++ b/OvmfPkg/OvmfPkgIa32X64.dsc
@@ -182,6 +182,7 @@ [LibraryClasses]
   LoadLinuxLib|OvmfPkg/Library/LoadLinuxLib/LoadLinuxLib.inf
   MemEncryptSevLib|OvmfPkg/Library/BaseMemEncryptSevLib/DxeMemEncryptSevLib.inf
   MemEncryptTdxLib|OvmfPkg/Library/BaseMemEncryptTdxLib/BaseMemEncryptTdxLibNull.inf
+  ProtectedVariableLib|MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
 !if $(SMM_REQUIRE) == FALSE
   LockBoxLib|OvmfPkg/Library/LockBoxLib/LockBoxBaseLib.inf
 !endif
diff --git a/OvmfPkg/OvmfPkgX64.dsc b/OvmfPkg/OvmfPkgX64.dsc
index 45ffa2dbe35f..32ebe045c03d 100644
--- a/OvmfPkg/OvmfPkgX64.dsc
+++ b/OvmfPkg/OvmfPkgX64.dsc
@@ -189,6 +189,7 @@ [LibraryClasses]
   LoadLinuxLib|OvmfPkg/Library/LoadLinuxLib/LoadLinuxLib.inf
   MemEncryptSevLib|OvmfPkg/Library/BaseMemEncryptSevLib/DxeMemEncryptSevLib.inf
   MemEncryptTdxLib|OvmfPkg/Library/BaseMemEncryptTdxLib/BaseMemEncryptTdxLib.inf
+  ProtectedVariableLib|MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
 
 !if $(SMM_REQUIRE) == FALSE
   LockBoxLib|OvmfPkg/Library/LockBoxLib/LockBoxBaseLib.inf
diff --git a/OvmfPkg/OvmfXen.dsc b/OvmfPkg/OvmfXen.dsc
index a1626d06dfc3..532a3e1b2027 100644
--- a/OvmfPkg/OvmfXen.dsc
+++ b/OvmfPkg/OvmfXen.dsc
@@ -1,7 +1,7 @@
 ## @file
 #  EFI/Framework Open Virtual Machine Firmware (OVMF) platform
 #
-#  Copyright (c) 2006 - 2021, Intel Corporation. All rights reserved.<BR>
+#  Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
 #  (C) Copyright 2016 Hewlett Packard Enterprise Development LP<BR>
 #  Copyright (c) 2019, Citrix Systems, Inc.
 #  Copyright (c) Microsoft Corporation.
@@ -218,6 +218,7 @@ [LibraryClasses]
 
   Tcg2PhysicalPresenceLib|OvmfPkg/Library/Tcg2PhysicalPresenceLibNull/DxeTcg2PhysicalPresenceLib.inf
   TpmMeasurementLib|MdeModulePkg/Library/TpmMeasurementLibNull/TpmMeasurementLibNull.inf
+  ProtectedVariableLib|MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
   RealTimeClockLib|OvmfPkg/Library/XenRealTimeClockLib/XenRealTimeClockLib.inf
   TimeBaseLib|EmbeddedPkg/Library/TimeBaseLib/TimeBaseLib.inf
 !ifdef $(DEBUG_ON_HYPERVISOR_CONSOLE)
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 24/28] OvmfPkg: Add ProtectedVariableLib reference
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (22 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 23/28] OvmfPkg: " Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-04-29 18:04 ` [Patch v2 25/28] " Judah Vang
                   ` (5 subsequent siblings)
  29 siblings, 0 replies; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel
  Cc: Jian J Wang, Jiewen Yao, Min Xu, Brijesh Singh, Erdem Aktas,
	James Bottomley, Tom Lendacky, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add reference to null ProtectedVariableLib.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Min Xu <min.m.xu@intel.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 OvmfPkg/AmdSev/AmdSevX64.dsc | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/OvmfPkg/AmdSev/AmdSevX64.dsc b/OvmfPkg/AmdSev/AmdSevX64.dsc
index f0700035c116..b0072f5fb0d3 100644
--- a/OvmfPkg/AmdSev/AmdSevX64.dsc
+++ b/OvmfPkg/AmdSev/AmdSevX64.dsc
@@ -3,7 +3,7 @@
 #  virtual machine remote attestation and secret injection
 #
 #  Copyright (c) 2020 James Bottomley, IBM Corporation.
-#  Copyright (c) 2006 - 2021, Intel Corporation. All rights reserved.<BR>
+#  Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
 #  (C) Copyright 2016 Hewlett Packard Enterprise Development LP<BR>
 #
 #  SPDX-License-Identifier: BSD-2-Clause-Patent
@@ -176,6 +176,7 @@ [LibraryClasses]
   FrameBufferBltLib|MdeModulePkg/Library/FrameBufferBltLib/FrameBufferBltLib.inf
   BlobVerifierLib|OvmfPkg/AmdSev/BlobVerifierLibSevHashes/BlobVerifierLibSevHashes.inf
   MemEncryptTdxLib|OvmfPkg/Library/BaseMemEncryptTdxLib/BaseMemEncryptTdxLib.inf
+  ProtectedVariableLib|MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
 
 !if $(SOURCE_DEBUG_ENABLE) == TRUE
   PeCoffExtraActionLib|SourceLevelDebugPkg/Library/PeCoffExtraActionLibDebug/PeCoffExtraActionLibDebug.inf
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 25/28] OvmfPkg: Add ProtectedVariableLib reference
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (23 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 24/28] OvmfPkg: Add ProtectedVariableLib reference Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-04-29 18:04 ` [Patch v2 26/28] " Judah Vang
                   ` (4 subsequent siblings)
  29 siblings, 0 replies; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Rebecca Cran, Peter Grehan, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add reference to null ProtectedVariableLib.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Rebecca Cran <rebecca@bsdio.com>
Cc: Peter Grehan <grehan@freebsd.org>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 OvmfPkg/Bhyve/BhyveX64.dsc | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/OvmfPkg/Bhyve/BhyveX64.dsc b/OvmfPkg/Bhyve/BhyveX64.dsc
index a8fa4d38ab60..5b36dc2358bb 100644
--- a/OvmfPkg/Bhyve/BhyveX64.dsc
+++ b/OvmfPkg/Bhyve/BhyveX64.dsc
@@ -1,6 +1,6 @@
 #
 #  Copyright (c) 2020, Rebecca Cran <rebecca@bsdio.com>
-#  Copyright (c) 2006 - 2021, Intel Corporation. All rights reserved.<BR>
+#  Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
 #  (C) Copyright 2016 Hewlett Packard Enterprise Development LP<BR>
 #  Copyright (c) 2014, Pluribus Networks, Inc.
 #
@@ -171,6 +171,7 @@ [LibraryClasses]
   MemEncryptSevLib|OvmfPkg/Library/BaseMemEncryptSevLib/DxeMemEncryptSevLib.inf
   LockBoxLib|OvmfPkg/Library/LockBoxLib/LockBoxBaseLib.inf
   MemEncryptTdxLib|OvmfPkg/Library/BaseMemEncryptTdxLib/BaseMemEncryptTdxLib.inf
+  ProtectedVariableLib|MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
 
   CustomizedDisplayLib|MdeModulePkg/Library/CustomizedDisplayLib/CustomizedDisplayLib.inf
   FrameBufferBltLib|MdeModulePkg/Library/FrameBufferBltLib/FrameBufferBltLib.inf
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 26/28] OvmfPkg: Add ProtectedVariableLib reference
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (24 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 25/28] " Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-04-29 18:04 ` [Patch v2 27/28] OvmfPkg: Add ProtectedVariable reference Judah Vang
                   ` (3 subsequent siblings)
  29 siblings, 0 replies; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Gerd Hoffmann, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add reference to null ProtectedVariableLib.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 OvmfPkg/Microvm/MicrovmX64.dsc | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/OvmfPkg/Microvm/MicrovmX64.dsc b/OvmfPkg/Microvm/MicrovmX64.dsc
index 20c3c9c4d862..723be8ad345c 100644
--- a/OvmfPkg/Microvm/MicrovmX64.dsc
+++ b/OvmfPkg/Microvm/MicrovmX64.dsc
@@ -1,7 +1,7 @@
 ## @file
 #  EFI/Framework Open Virtual Machine Firmware (OVMF) platform
 #
-#  Copyright (c) 2006 - 2021, Intel Corporation. All rights reserved.<BR>
+#  Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
 #  (C) Copyright 2016 Hewlett Packard Enterprise Development LP<BR>
 #  Copyright (c) Microsoft Corporation.
 #
@@ -183,6 +183,7 @@ [LibraryClasses]
   CustomizedDisplayLib|MdeModulePkg/Library/CustomizedDisplayLib/CustomizedDisplayLib.inf
   FrameBufferBltLib|MdeModulePkg/Library/FrameBufferBltLib/FrameBufferBltLib.inf
   MemEncryptTdxLib|OvmfPkg/Library/BaseMemEncryptTdxLib/BaseMemEncryptTdxLib.inf
+  ProtectedVariableLib|MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
 
 !if $(SOURCE_DEBUG_ENABLE) == TRUE
   PeCoffExtraActionLib|SourceLevelDebugPkg/Library/PeCoffExtraActionLibDebug/PeCoffExtraActionLibDebug.inf
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 27/28] OvmfPkg: Add ProtectedVariable reference
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (25 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 26/28] " Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-03  7:30   ` [edk2-devel] " Ard Biesheuvel
  2022-04-29 18:04 ` [Patch v2 28/28] CryptoPkg: Enable cypto HMAC KDF library Judah Vang
                   ` (2 subsequent siblings)
  29 siblings, 1 reply; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jian J Wang, Sebastien Boeuf, Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add reference to null ProtectedVariableLib.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Sebastien Boeuf <sebastien.boeuf@intel.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 OvmfPkg/CloudHv/CloudHvX64.dsc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/OvmfPkg/CloudHv/CloudHvX64.dsc b/OvmfPkg/CloudHv/CloudHvX64.dsc
index d1c85f60c768..3ec7e860c613 100644
--- a/OvmfPkg/CloudHv/CloudHvX64.dsc
+++ b/OvmfPkg/CloudHv/CloudHvX64.dsc
@@ -180,6 +180,7 @@ [LibraryClasses]
   VirtioLib|OvmfPkg/Library/VirtioLib/VirtioLib.inf
   LoadLinuxLib|OvmfPkg/Library/LoadLinuxLib/LoadLinuxLib.inf
   MemEncryptSevLib|OvmfPkg/Library/BaseMemEncryptSevLib/DxeMemEncryptSevLib.inf
+  ProtectedVariableLib|MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
 !if $(SMM_REQUIRE) == FALSE
   LockBoxLib|OvmfPkg/Library/LockBoxLib/LockBoxBaseLib.inf
 !endif
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* [Patch v2 28/28] CryptoPkg: Enable cypto HMAC KDF library
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (26 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 27/28] OvmfPkg: Add ProtectedVariable reference Judah Vang
@ 2022-04-29 18:04 ` Judah Vang
  2022-05-17  2:48 ` [edk2-devel] [Patch v2 00/28] UEFI variable protection Michael Kubacki
       [not found] ` <16EFC4965F71DFB8.20068@groups.io>
  29 siblings, 0 replies; 49+ messages in thread
From: Judah Vang @ 2022-04-29 18:04 UTC (permalink / raw)
  To: devel; +Cc: Jiewen Yao, Jian J Wang, Xiaoyu Lu, Guomin Jiang,
	Nishant C Mistry

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

RPMC confidentiality feature requires HMAC-SHA256 support during
SMM phase. This allows the protected variable's data to be
encrypted in the SPI flash.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Xiaoyu Lu <xiaoyux.lu@intel.com>
Cc: Guomin Jiang <guomin.jiang@intel.com>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 CryptoPkg/Library/BaseCryptLib/SmmCryptLib.inf | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/CryptoPkg/Library/BaseCryptLib/SmmCryptLib.inf b/CryptoPkg/Library/BaseCryptLib/SmmCryptLib.inf
index ae75bc87b5e5..28ad0bf0816d 100644
--- a/CryptoPkg/Library/BaseCryptLib/SmmCryptLib.inf
+++ b/CryptoPkg/Library/BaseCryptLib/SmmCryptLib.inf
@@ -43,7 +43,7 @@ [Sources]
   Hash/CryptCShake256.c
   Hash/CryptParallelHash.c
   Hmac/CryptHmacSha256.c
-  Kdf/CryptHkdfNull.c
+  Kdf/CryptHkdf.c
   Cipher/CryptAes.c
   Pk/CryptRsaBasic.c
   Pk/CryptRsaExtNull.c
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* Re: [Patch v2 21/28] UefiPayloadPkg: Add ProtectedVariable reference
  2022-04-29 18:04 ` [Patch v2 21/28] UefiPayloadPkg: Add ProtectedVariable reference Judah Vang
@ 2022-04-29 21:03   ` Guo Dong
  0 siblings, 0 replies; 49+ messages in thread
From: Guo Dong @ 2022-04-29 21:03 UTC (permalink / raw)
  To: Vang, Judah, devel@edk2.groups.io
  Cc: Wang, Jian J, Ni, Ray, Maurice Ma, You, Benjamin, Rhodes, Sean,
	Mistry, Nishant C


Reviewed-by: Guo Dong <guo.dong@intel.com>

-----Original Message-----
From: Vang, Judah <judah.vang@intel.com> 
Sent: Friday, April 29, 2022 11:04 AM
To: devel@edk2.groups.io
Cc: Wang, Jian J <jian.j.wang@intel.com>; Dong, Guo <guo.dong@intel.com>; Ni, Ray <ray.ni@intel.com>; Maurice Ma <maurice.ma@intel.com>; You, Benjamin <benjamin.you@intel.com>; Rhodes, Sean <sean@starlabs.systems>; Mistry, Nishant C <nishant.c.mistry@intel.com>
Subject: [Patch v2 21/28] UefiPayloadPkg: Add ProtectedVariable reference

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594

Add reference for ProtectedVariableLib so build is successful.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Guo Dong <guo.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Maurice Ma <maurice.ma@intel.com>
Cc: Benjamin You <benjamin.you@intel.com>
Cc: Sean Rhodes <sean@starlabs.systems>
Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
Signed-off-by: Judah Vang <judah.vang@intel.com>
---
 UefiPayloadPkg/UefiPayloadPkg.dsc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/UefiPayloadPkg/UefiPayloadPkg.dsc b/UefiPayloadPkg/UefiPayloadPkg.dsc
index 17b30589e77c..fe835eed1bc7 100644
--- a/UefiPayloadPkg/UefiPayloadPkg.dsc
+++ b/UefiPayloadPkg/UefiPayloadPkg.dsc
@@ -263,9 +263,11 @@ [LibraryClasses]
   AuthVariableLib|MdeModulePkg/Library/AuthVariableLibNull/AuthVariableLibNull.inf
 !if $(VARIABLE_SUPPORT) == "EMU"
   TpmMeasurementLib|MdeModulePkg/Library/TpmMeasurementLibNull/TpmMeasurementLibNull.inf
+  ProtectedVariableLib|MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
 !elseif $(VARIABLE_SUPPORT) == "SPI"
   PlatformSecureLib|SecurityPkg/Library/PlatformSecureLibNull/PlatformSecureLibNull.inf
   TpmMeasurementLib|SecurityPkg/Library/DxeTpmMeasurementLib/DxeTpmMeasurementLib.inf
+  ProtectedVariableLib|SecurityPkg/Library/ProtectedVariableLib/DxeProtectedVariableLib.inf
   S3BootScriptLib|MdePkg/Library/BaseS3BootScriptLibNull/BaseS3BootScriptLibNull.inf
   MmUnblockMemoryLib|MdePkg/Library/MmUnblockMemoryLib/MmUnblockMemoryLibNull.inf
 !endif
-- 
2.35.1.windows.2


^ permalink raw reply related	[flat|nested] 49+ messages in thread

* Re: [Patch v2 20/28] ArmVirtPkg: Add reference to ProtectedVariableNull
  2022-04-29 18:04 ` [Patch v2 20/28] ArmVirtPkg: Add reference to ProtectedVariableNull Judah Vang
@ 2022-05-03  7:29   ` Ard Biesheuvel
  0 siblings, 0 replies; 49+ messages in thread
From: Ard Biesheuvel @ 2022-05-03  7:29 UTC (permalink / raw)
  To: Judah Vang
  Cc: edk2-devel-groups-io, Jian J Wang, Ard Biesheuvel, Leif Lindholm,
	Nishant C Mistry

On Fri, 29 Apr 2022 at 20:05, Judah Vang <judah.vang@intel.com> wrote:
>
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594
>
> Need reference to ProtectVariableNullLib otherwise build fails.
>
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
> Cc: Leif Lindholm <quic_llindhol@quicinc.com>
> Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Judah Vang <judah.vang@intel.com>

Acked-by: Ard Biesheuvel <ardb@kernel.org>

> ---
>  ArmVirtPkg/ArmVirtQemu.dsc | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/ArmVirtPkg/ArmVirtQemu.dsc b/ArmVirtPkg/ArmVirtQemu.dsc
> index aa0ce61630f7..cdebd94a9fce 100644
> --- a/ArmVirtPkg/ArmVirtQemu.dsc
> +++ b/ArmVirtPkg/ArmVirtQemu.dsc
> @@ -1,7 +1,7 @@
>  #
>  #  Copyright (c) 2011-2015, ARM Limited. All rights reserved.
>  #  Copyright (c) 2014, Linaro Limited. All rights reserved.
> -#  Copyright (c) 2015 - 2020, Intel Corporation. All rights reserved.
> +#  Copyright (c) 2015 - 2022, Intel Corporation. All rights reserved.
>  #
>  #  SPDX-License-Identifier: BSD-2-Clause-Patent
>  #
> @@ -81,6 +81,7 @@ [LibraryClasses.common]
>    PciSegmentLib|MdePkg/Library/BasePciSegmentLibPci/BasePciSegmentLibPci.inf
>    PciHostBridgeLib|OvmfPkg/Fdt/FdtPciHostBridgeLib/FdtPciHostBridgeLib.inf
>    PciHostBridgeUtilityLib|OvmfPkg/Library/PciHostBridgeUtilityLib/PciHostBridgeUtilityLib.inf
> +  ProtectedVariableLib|MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
>
>  !if $(TPM2_ENABLE) == TRUE
>    Tpm2CommandLib|SecurityPkg/Library/Tpm2CommandLib/Tpm2CommandLib.inf
> --
> 2.35.1.windows.2
>

^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [edk2-devel] [Patch v2 27/28] OvmfPkg: Add ProtectedVariable reference
  2022-04-29 18:04 ` [Patch v2 27/28] OvmfPkg: Add ProtectedVariable reference Judah Vang
@ 2022-05-03  7:30   ` Ard Biesheuvel
  0 siblings, 0 replies; 49+ messages in thread
From: Ard Biesheuvel @ 2022-05-03  7:30 UTC (permalink / raw)
  To: edk2-devel-groups-io, Judah Vang
  Cc: Jian J Wang, Sebastien Boeuf, Nishant C Mistry

On Fri, 29 Apr 2022 at 20:05, Judah Vang <judah.vang@intel.com> wrote:
>
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594
>
> Add reference to null ProtectedVariableLib.
>
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Sebastien Boeuf <sebastien.boeuf@intel.com>
> Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Judah Vang <judah.vang@intel.com>

Acked-by: Ard Biesheuvel <ardb@kernel.org>

> ---
>  OvmfPkg/CloudHv/CloudHvX64.dsc | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/OvmfPkg/CloudHv/CloudHvX64.dsc b/OvmfPkg/CloudHv/CloudHvX64.dsc
> index d1c85f60c768..3ec7e860c613 100644
> --- a/OvmfPkg/CloudHv/CloudHvX64.dsc
> +++ b/OvmfPkg/CloudHv/CloudHvX64.dsc
> @@ -180,6 +180,7 @@ [LibraryClasses]
>    VirtioLib|OvmfPkg/Library/VirtioLib/VirtioLib.inf
>    LoadLinuxLib|OvmfPkg/Library/LoadLinuxLib/LoadLinuxLib.inf
>    MemEncryptSevLib|OvmfPkg/Library/BaseMemEncryptSevLib/DxeMemEncryptSevLib.inf
> +  ProtectedVariableLib|MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
>  !if $(SMM_REQUIRE) == FALSE
>    LockBoxLib|OvmfPkg/Library/LockBoxLib/LockBoxBaseLib.inf
>  !endif
> --
> 2.35.1.windows.2
>
>
>
> 
>
>

^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [Patch v2 06/28] MdeModulePkg: Add new include files
  2022-04-29 18:04 ` [Patch v2 06/28] MdeModulePkg: Add new include files Judah Vang
@ 2022-05-12  9:31   ` Wang, Jian J
  0 siblings, 0 replies; 49+ messages in thread
From: Wang, Jian J @ 2022-05-12  9:31 UTC (permalink / raw)
  To: Vang, Judah, devel@edk2.groups.io; +Cc: Gao, Liming, Mistry, Nishant C

Hi Judah,

Please check my comments inlined below.

Regards,
Jian

> -----Original Message-----
> From: Vang, Judah <judah.vang@intel.com>
> Sent: Saturday, April 30, 2022 2:04 AM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Gao, Liming
> <gaoliming@byosoft.com.cn>; Mistry, Nishant C <nishant.c.mistry@intel.com>
> Subject: [Patch v2 06/28] MdeModulePkg: Add new include files
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594
> 
> Add EncryptionVariableLib.h for providing encryption and
> decryption services for protected variables.
> Add ProtectedVariableLib.h for providing integrity or
> variables.
> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Liming Gao <gaoliming@byosoft.com.cn>
> Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Judah Vang <judah.vang@intel.com>
> ---
>  MdeModulePkg/Include/Library/EncryptionVariableLib.h | 165 +++++
>  MdeModulePkg/Include/Library/ProtectedVariableLib.h  | 700
> ++++++++++++++++++++
>  2 files changed, 865 insertions(+)
> 
> diff --git a/MdeModulePkg/Include/Library/EncryptionVariableLib.h
> b/MdeModulePkg/Include/Library/EncryptionVariableLib.h
> new file mode 100644
> index 000000000000..c7740e659dcf
> --- /dev/null
> +++ b/MdeModulePkg/Include/Library/EncryptionVariableLib.h
> @@ -0,0 +1,165 @@
> +/** @file
> +  Provides services to encrypt/decrypt variables.
> +
> +Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
> +SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#ifndef ENCRYPTION_VARIABLE_LIB_H_
> +#define ENCRYPTION_VARIABLE_LIB_H_
> +
> +#include <IndustryStandard/Tpm20.h>
> +
> +#include <Guid/VariableFormat.h>
> +
> +#include <Library/AuthVariableLib.h>
> +
> +#define ENC_TYPE_NULL  0
> +#define ENC_TYPE_AES   TPM_ALG_AES
> +
> +typedef struct  _VARIABLE_ENCRYPTION_FLAGS {
> +  BOOLEAN    Auth;            // Variable is authenticated or not
> +  BOOLEAN    DecryptInPlace;  // Do decryption in place
> +  BOOLEAN    Protected;       // Variable is protected or not
> +} VARIABLE_ENCRYPTION_FLAGS;
> +
> +typedef struct _VARIABLE_ENCRYPTION_INFO {
> +  AUTH_VARIABLE_INFO           Header;            // Authenticated varabile header
> +  VARIABLE_HEADER              *Buffer;           // Pointer to variable buffer
> +  UINT64                       StoreIndex;        // Variable store index
> +  VOID                         *PlainData;        // Pointer to plain data
> +  UINT32                       PlainDataSize;     // Size of plain data
> +  VOID                         *CipherData;       // Pointer to cipher data
> +  UINT32                       CipherDataSize;    // Size of cipher data
> +  UINT32                       CipherHeaderSize;  // Size of cipher header
> +  UINT32                       CipherDataType;    // Type of cipher data
> +  VOID                         *Key;              // Pointer to encrypt/decrypt key
> +  UINT32                       KeySize;           // Size of key
> +  VARIABLE_ENCRYPTION_FLAGS    Flags;             // Encryption flags
> +} VARIABLE_ENCRYPTION_INFO;
> +
> +/**
> +  Encrypt variable data.
> +
> +  @param[in, out]   VarInfo   Pointer to structure containing detailed
> information about a variable.
> +
> +  @retval EFI_SUCCESS               Function successfully executed.
> +  @retval EFI_INVALID_PARAMETER     If ProtectedVarLibContextIn == NULL or
> ProtectedVarLibContextOut == NULL.
> +  @retval EFI_OUT_OF_RESOURCES      Fail to allocate enough resource.
> +  @retval EFI_UNSUPPORTED           Unsupported to process authenticated
> variable.

[JianJW] authenticated -> encrypted

> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +EncryptVariable (
> +  IN OUT VARIABLE_ENCRYPTION_INFO  *VarInfo
> +  );
> +
> +/**
> +  Decrypt variable data.
> +
> +  If VarEncInfo->CipherData is not NULL, it must holds the cipher data to be
> +  decrypted. Otherwise, assume the cipher data from variable data buffer, i.e.
> +  VarEncInfo->Header.Data.
> +
> +  If VarEncInfo->Flags.DecryptInPlace is TRUE, the decrypted data will be put
> +  back in the same buffer as cipher buffer got above, after encryption header,
> +  which helps to identify later if the data in buffer is decrypted or not. This
> +  can avoid repeat decryption when accessing the same variable more than
> once.
> +
> +  If VarEncInfo->Flags.DecryptInPlace is FALSE, VarEncInfo->PlainData must be
> +  passed in with a valid buffer with VarEncInfo->PlainDataSize set correctly
> +  with its size.
> +
> +  Note the VarEncInfo->PlainData is always pointing to the buffer address with
> +  decrypted data without encryption header, and VarEncInfo->PlainDataSize is
> +  always the size of original variable data, if this function returned
> +  successfully.
> +
> +  @param[in, out]   VarInfo   Pointer to structure containing detailed
> +                              information about a variable.
> +
> +  @retval EFI_SUCCESS             Variable was decrypted successfully.
> +  @retval EFI_INVALID_PARAMETER   Variable information in VarEncInfo is
> invalid.
> +  @retval EFI_BUFFER_TOO_SMALL    VarEncInfo->PlainData is not NULL but
> +                                  VarEncInfo->PlainDataSize is too small.
> +  @retval EFI_ABORTED             Uknown error occurred during decrypting.

[JianJW] Uknown -> Unknown

> +  @retval EFI_OUT_OF_RESOURCES    Fail to allocate enough resource.
> +  @retval EFI_COMPROMISED_DATA    The cipher header is not valid.
> +  @retval EFI_UNSUPPORTED         Unsupported to encrypt variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +DecryptVariable (
> +  IN OUT VARIABLE_ENCRYPTION_INFO  *VarInfo
> +  );
> +
> +/**
> +  Get cipher information about a variable, including plaindata size,
> +  cipher algorithm type, etc.
> +
> +  For data passed in with VarEncInfo,
> +
> +    VarEncInfo->Header.Data
> +      - The variable data in normal variable structure.
> +    VarEncInfo->Header.DataSize
> +      - The size of variable data.
> +
> +  For data passed out with VarEncInfo (valid only if EFI_SUCCESS is returned),
> +
> +    VarEncInfo->CipherDataType
> +      - ENC_TYPE_NULL, if the variable is not encrypted or has been decrypted;
> +      - ENC_TYPE_AES, if the variable is encrypted.
> +    VarEncInfo->CipherHeaderSize
> +      - Size of cipher header put before encrypted or decrypted data.
> +    VarEncInfo->PlainData
> +      - NULL, if the variable is encrypted; Or
> +      - pointer to original variable data, if the variable has been decrypted.
> +    VarEncInfo->PlainDataSize
> +      - The size of original variable data
> +    VarEncInfo->CipherData
> +      - NULL, if the variable is decrypted; Or
> +      - pointer to start of encrypted variable data, including encryption header;
> +    VarEncInfo->CipherDataSize
> +      - The size of encrypted variable data, including encryption header.
> +
> +  @param[in, out]   VarInfo   Pointer to structure containing detailed
> +                              information about a variable.
> +
> +  @retval EFI_SUCCESS             The information was retrieved successfully.
> +  @retval EFI_INVALID_PARAMETER   Variable information in VarEncInfo is
> invalid.
> +  @retval EFI_NOT_FOUND           No cipher information recognized.
> +  @retval EFI_UNSUPPORTED         Unsupported interface.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +GetCipherDataInfo (
> +  IN  OUT VARIABLE_ENCRYPTION_INFO  *VarInfo
> +  );
> +
> +/**
> +  Force set cipher information for a variable, like plaindata size,
> +  cipher algorithm type, cipher data etc.
> +
> +  The destination buffer must be passed via VarEncInfo->Header.Data.
> +
> +  This method is only used to update and/or change plain data information.
> +
> +  @param[in, out]   VarInfo   Pointer to structure containing detailed
> +                              information about a variable.
> +
> +  @retval EFI_SUCCESS             The information was updated successfully.
> +  @retval EFI_INVALID_PARAMETER   Variable information in VarEncInfo is
> invalid.
> +  @retval EFI_UNSUPPORTED         If this method is not supported.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +SetCipherDataInfo (
> +  IN  OUT VARIABLE_ENCRYPTION_INFO  *VarInfo
> +  );
> +
> +#endif //_ENCRYPTION_VARIABLE_LIB_H_
> diff --git a/MdeModulePkg/Include/Library/ProtectedVariableLib.h
> b/MdeModulePkg/Include/Library/ProtectedVariableLib.h
> new file mode 100644
> index 000000000000..2f57b4ebbc70
> --- /dev/null
> +++ b/MdeModulePkg/Include/Library/ProtectedVariableLib.h
> @@ -0,0 +1,700 @@
> +/** @file
> +  Defines interfaces of protected variable services for non-volatile variable
> +  storage.
> +
> +Copyright (c) 2020 - 2022, Intel Corporation. All rights reserved.<BR>
> +SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#ifndef PROTECTED_VARIABLE_LIB_H_
> +#define PROTECTED_VARIABLE_LIB_H_
> +
> +#include <PiPei.h>
> +#include <PiDxe.h>
> +
> +#include <Guid/VariableFormat.h>
> +
> +#include <Protocol/VarCheck.h>
> +#include <Protocol/FirmwareVolumeBlock.h>
> +
> +#include <Library/UefiLib.h>
> +#include <Library/EncryptionVariableLib.h>
> +
> +#pragma pack(1)
> +
> +typedef struct _VARIABLE_DIGEST_FLAGS {
> +  BOOLEAN    Auth;                           // Authenticated variable format
> +  BOOLEAN    Valid;                          // Valid variable data in current variable
> +  BOOLEAN    Protected;                      // Protected variable (used in calculating
> HMAC)
> +  BOOLEAN    Encrypted;                      // Encrypted variable
> +  BOOLEAN    Freeable;                       // Memory reserved for current node can
> be freed
> +  BOOLEAN    CacheIndexAhead;                // Indicates if CacheIndex is Ahead
> relative to Global structure
> +  BOOLEAN    Reserved[2];                    // Reserved fields
> +} VARIABLE_DIGEST_FLAGS;
> +
> +typedef struct _VARIABLE_DIGEST {
> +  ///
> +  /// Pointer to digest of next variable in a pre-defined rule of order for
> +  /// integration verification. In other words, the final HMAC of all
> +  /// protected variables is calculated by concatenating digest of each
> +  /// variable in the order of this singly linked list.
> +  ///
> +  EFI_PHYSICAL_ADDRESS     Prev;
> +  EFI_PHYSICAL_ADDRESS     Next;
> +  ///
> +  /// Index to variable in physical store, used to locate the variable directly
> +  /// inside the store (Implementation dependent).
> +  ///
> +  EFI_PHYSICAL_ADDRESS     StoreIndex;
> +  ///
> +  /// Index to variable in memory cache, used to locate the variable directly
> +  /// inside the cache (Implementation dependent).
> +  ///
> +  EFI_PHYSICAL_ADDRESS     CacheIndex;
> +
> +  ///
> +  /// Pointer to Cache offset within Global Structure
> +  ///
> +  UINT32                   CacheOffset;
> +
> +  ///
> +  /// Frequently accessed information relating to the variable.
> +  ///
> +  UINT16                   DigestSize;    // Size of digest value
> +  UINT16                   NameSize;      // Size of variable name
> +  UINT32                   DataSize;      // Size of variable data
> +  UINT32                   PlainDataSize; // Size of plain data of current variable (if
> encrypted)
> +  UINT32                   State;         // State of current variable
> +  UINT32                   Attributes;    // Attributes of current variable
> +
> +  EFI_GUID                 VendorGuid;    // GUID
> +  VARIABLE_DIGEST_FLAGS    Flags;         // Variable digest flags
> +  //
> +  // Data with variable length are put at the end of this structure.
> +  //
> +  // CHAR16                VariableName[NameSize/2];
> +  // UINT8                 DigestValue[DigestSize];
> +} VARIABLE_DIGEST;
> +
> +#pragma pack()
> +
> +#define VAR_DIG_NAMEOFF(VarDig)  (sizeof (VARIABLE_DIGEST))
> +#define VAR_DIG_DIGOFF(VarDig)   (VAR_DIG_NAMEOFF (VarDig) + (VarDig)-
> >NameSize)
> +
> +#define VAR_DIG_END(VarDig)  (VAR_DIG_DIGOFF (VarDig) + (VarDig)-
> >DigestSize)
> +
> +#define VAR_DIG_VALUE(VarDig)  (VOID *)((UINTN)(VarDig) +
> VAR_DIG_DIGOFF (VarDig))
> +#define VAR_DIG_NAME(VarDig)   (CHAR16 *)((UINTN)(VarDig) +
> VAR_DIG_NAMEOFF (VarDig))
> +#define VAR_DIG_GUID(VarDig)   &(VAR_DIG_PTR (VarDig)->VendorGuid)
> +
> +#define VAR_DIG_PTR(Addr)     ((VARIABLE_DIGEST *)(UINTN)(Addr))
> +#define VAR_DIG_ADR(Ptr)      ((EFI_PHYSICAL_ADDRESS)(UINTN)(Ptr))
> +#define VAR_DIG_NEXT(VarDig)  (VAR_DIG_PTR ((VarDig)->Next))
> +#define VAR_DIG_PREV(VarDig)  (VAR_DIG_PTR ((VarDig)->Prev))
> +
> +#define VAR_INDEX_INVALID  ((UINT64)(-1))
> +
> +#define VAR_HDR_PTR(Addr)  ((VARIABLE_HEADER *)(UINTN)(Addr))
> +
> +typedef VARIABLE_ENCRYPTION_INFO PROTECTED_VARIABLE_INFO;
> +
> +/**
> +
> +  This function writes data to the NV variable storage at given position.
> +
> +  Note: Per current variable service architecture, only SMM is allowed to
> +        (directly) change NV variable storage.
> +
> +  @param VariableInfo             Pointer to structure holding details of a variable.
> +  @param Offset                   Offset to the given variable to write from.
> +  @param Size                     Size of data to be written.
> +  @param Buffer                   Pointer to the buffer from which data is written.
> +
> +  @retval EFI_INVALID_PARAMETER  Invalid parameters passed in.
> +  @retval EFI_UNSUPPORTED        Updating NV variable storage is not
> supported.
> +  @retval EFI_OUT_OF_RESOURCES   Not enough resource to complete the
> operation.
> +  @retval EFI_SUCCESS            Variable store successfully updated.
> +
> +**/
> +typedef
> +EFI_STATUS
> +(EFIAPI *PROTECTED_VAR_LIB_UPDATE_VARIABLE_STORE)(
> +  IN  PROTECTED_VARIABLE_INFO     *VariableInfo,
> +  IN  UINTN                       Offset,
> +  IN  UINT32                      Size,
> +  IN  UINT8                       *Buffer
> +  );
> +
> +/**
> +  Update the variable region with Variable information.
> +
> +  @param[in] AuthVariableInfo       Pointer AUTH_VARIABLE_INFO structure for
> +                                    input of the variable.

[JianJW] "Pointer" -> "Pointer to"

> +
> +  @retval EFI_SUCCESS               The update operation is success.
> +  @retval EFI_INVALID_PARAMETER     Invalid parameter.
> +  @retval EFI_WRITE_PROTECTED       Variable is write-protected.
> +  @retval EFI_OUT_OF_RESOURCES      There is not enough resource.
> +
> +**/
> +typedef
> +EFI_STATUS
> +(EFIAPI *PROTECTED_VAR_LIB_UPDATE_VARIABLE)(
> +  IN AUTH_VARIABLE_INFO     *AuthVariableInfo
> +  );
> +
> +/**
> +
> +  Retrieve details about a variable and return them in VariableInfo->Header.
> +
> +  If VariableInfo->Address is given, this function will calculate its offset
> +  relative to given variable storage via VariableStore; Otherwise, it will try
> +  other internal variable storages or cached copies. It's assumed that, for all
> +  copies of NV variable storage, all variables are stored in the same relative
> +  position. If VariableInfo->Address is found in the range of any storage copies,
> +  its offset relative to that storage should be the same in other copies.
> +
> +  If VariableInfo->Offset is given (non-zero) but not VariableInfo->Address,
> +  this function will return the variable memory address inside VariableStore,
> +  if given, via VariableInfo->Address; Otherwise, the address of other storage
> +  copies will be returned, if any.
> +
> +  For a new variable whose offset has not been determined, a value of -1 as
> +  VariableInfo->Offset should be passed to skip the offset calculation.
> +
> +  @param VariableInfo             Pointer to variable information.
> +
> +  @retval EFI_INVALID_PARAMETER  VariableInfo is NULL or both VariableInfo-
> >Address
> +                                 and VariableInfo->Offset are NULL (0).
> +  @retval EFI_NOT_FOUND          If given Address or Offset is out of range of
> +                                 any given or internal storage copies.
> +  @retval EFI_SUCCESS            Variable details are retrieved successfully.
> +
> +**/
> +typedef
> +EFI_STATUS
> +(EFIAPI *PROTECTED_VAR_LIB_GET_VAR_INFO)(
> +  IN  OUT PROTECTED_VARIABLE_INFO   *VariableInfo
> +  );
> +
> +/**
> +
> +  Retrieve details of the variable next to given variable within VariableStore.
> +
> +  If VarInfo->Address is NULL, the first one in VariableStore is returned.
> +
> +  VariableStart and/or VariableEnd can be given optionally for the situation
> +  in which the valid storage space is smaller than the VariableStore->Size.
> +  This usually happens when PEI variable services make a compact variable
> +  cache to save memory, which cannot make use VariableStore->Size to
> determine
> +  the correct variable storage range.
> +
> +  @param VariableStore            Pointer to a variable storage. It's optional.
> +  @param VariableStart            Start point of valid range in VariableStore.
> +  @param VariableEnd              End point of valid range in VariableStore.
> +  @param VariableInfo             Pointer to variable information.
> +
> +  @retval EFI_INVALID_PARAMETER  VariableInfo or VariableStore is NULL.
> +  @retval EFI_NOT_FOUND          If the end of VariableStore is reached.
> +  @retval EFI_SUCCESS            The next variable is retrieved successfully.

[JianJW] The list of @param and @retval don't match the function prototype

> +
> +**/
> +typedef
> +EFI_STATUS
> +(EFIAPI *PROTECTED_VAR_LIB_GET_NEXT_VAR_INFO)(
> +  IN  OUT PROTECTED_VARIABLE_INFO   *VariableInfo
> +  );
> +
> +typedef
> +EFI_STATUS
> +(EFIAPI *DIGEST_METHOD_CALLBACK)(
> +  IN      VARIABLE_HEADER           *Variable,
> +  IN  OUT VARIABLE_DIGEST        *Digest
> +  );

[JianJW] Missing function header comment

> +
> +/**
> +
> +  Initialize a memory copy of NV variable storage.
> +
> +  To save memory consumption (especially in PEI phase), it's allowed to cache
> +  only valid variables. In such case, an index table recording offset of each
> +  valid variables could be employed. The index table makes sure the cached
> copy
> +  to be synchronized with the original copy in NV variable storage. To avoid
> +  TOCTOU issue, once the variables are cached in memory and verified, NV
> +  variable storage should not be used to read variable information. The cached
> +  copy should be used instead.
> +
> +  If StoreCacheBase is not given, this function should return the required
> +  cache size and valid variable number, if VariableNumber is not NULL. Then
> +  the caller can prepare correct cache buffer and index table buffer before
> +  next calling.
> +
> +  @param[in]      CacheBase       Base address of NV variable storage cache.
> +  @param[in]      CacheSize       Size of CacheBuffer.
> +  @param[out]     CacheSize       Size of required cache buffer.
> +  @param[out]     DigBuffer       Base address of digest of each variable.
> +  @param[in, out] DigBufferSize   Digest size of one variable if DigestBuffer is
> NULL.
> +                                  Size of DigestBuffer if DigestBuffer is NOT NULL.
> +  @param[out]     DigSize         Required size of DigestBuffer if DigestBuffer is
> NULL.
> +  @param[out]     DigMethod       Method used to generate digest for each
> variable.
> +  @param[out]     VarNumber       Number of valid variables.
> +  @param[out]     AuthFlag        Auth-variable indicator.
> +
> +  @retval EFI_INVALID_PARAMETER   CacheSize is NULL; Or,
> +                                  StoreCacheBase is 0 but *CacheSize it not.
> +  @retval EFI_VOLUME_CORRUPTED    If original NV variable storage is
> corrupted.
> +  @retval EFI_BUFFER_TOO_SMALL    If *CacheSize is smaller than required
> memory.
> +  @retval EFI_SUCCESS             The cached variable storage is initialized.
> +
> +**/
> +typedef
> +EFI_STATUS
> +(EFIAPI *PROTECTED_VAR_LIB_INIT_VAR_STORE)(
> +  OUT  VOID                      *CacheBase OPTIONAL,
> +  IN OUT  UINT32                    *CacheSize OPTIONAL,
> +  OUT  VOID                      *DigBuffer OPTIONAL,
> +  IN OUT  UINT32                    *DigBufferSize OPTIONAL,
> +  IN      UINT32                    DigSize OPTIONAL,
> +  IN      DIGEST_METHOD_CALLBACK    DigMethod OPTIONAL,
> +  OUT  UINT32                    *VarNumber OPTIONAL,
> +  OUT  BOOLEAN                   *AuthFlag OPTIONAL
> +  );

[JianJW] This function and above one are not used at all. Please remove it.

> +
> +/**
> +
> +  Initiate a variable retrieval in SMM environment from non-SMM environment.
> +
> +  This is usually required in BS/RT environment when local cached copy is in
> +  encrypted form. Variable decryption can only be done in SMM environment.
> +
> +  @param[in]      VariableName       Name of Variable to be found.
> +  @param[in]      VendorGuid         Variable vendor GUID.
> +  @param[out]     Attributes         Attribute value of the variable found.
> +  @param[in, out] DataSize           Size of Data found. If size is less than the
> +                                     data, this value contains the required size.
> +  @param[out]     Data               Data pointer.
> +
> +  @retval EFI_SUCCESS                Found the specified variable.
> +  @retval EFI_INVALID_PARAMETER      Invalid parameter.
> +  @retval EFI_NOT_FOUND              The specified variable could not be found.
> +
> +**/
> +typedef
> +EFI_STATUS
> +(EFIAPI *PROTECTED_VAR_LIB_FIND_VAR_SMM)(
> +  IN      CHAR16                     *VariableName,
> +  IN      EFI_GUID                   *VendorGuid,
> +  OUT UINT32                     *Attributes OPTIONAL,
> +  IN  OUT UINTN                      *DataSize,
> +  OUT VOID                       *Data OPTIONAL
> +  );

[JianJW] The parameters are not aligned.

> +
> +/**
> +  Check if a variable is user variable or not.
> +
> +  @param[in] Variable   Pointer to variable header.
> +
> +  @retval TRUE          User variable.
> +  @retval FALSE         System variable.
> +
> +**/
> +typedef
> +BOOLEAN
> +(EFIAPI *PROTECTED_VAR_LIB_IS_USER_VAR)(
> +  IN VARIABLE_HEADER    *Variable
> +  );

[JianJW] This function type is not used at all. Please remove it.

> +
> +/**
> +  Check if a HOB variable store is available or not.
> +
> +  @retval EFI_NOT_READY  HOB variable store info not available.
> +  @retval EFI_NOT_FOUND  HOB variable store is NOT available.
> +  @retval EFI_SUCCESS    HOB variable store is available.
> +**/
> +typedef
> +EFI_STATUS
> +(EFIAPI *PROTECTED_VAR_LIB_HOB_STORE_AVAILABLE)(
> +  VOID
> +  );
> +
> +typedef enum {
> +  FromPeiModule,
> +  FromBootServiceModule,
> +  FromRuntimeModule,
> +  FromSmmModule
> +} VARIABLE_SERVICE_USER;
> +
> +#pragma pack(1)
> +
> +#define PROTECTED_VARIABLE_CONTEXT_IN_STRUCT_VERSION  0x02
> +
> +typedef struct _PROTECTED_VARIABLE_CONTEXT_IN {
> +  UINT32                                     StructVersion;
> +  UINT32                                     StructSize;
> +  UINT32                                     MaxVariableSize;
> +
> +  VARIABLE_SERVICE_USER                      VariableServiceUser;
> +
> +  PROTECTED_VAR_LIB_FIND_VAR_SMM             FindVariableSmm;
> +  PROTECTED_VAR_LIB_GET_VAR_INFO             GetVariableInfo;
> +  PROTECTED_VAR_LIB_GET_NEXT_VAR_INFO        GetNextVariableInfo;
> +  PROTECTED_VAR_LIB_UPDATE_VARIABLE_STORE    UpdateVariableStore;
> +  PROTECTED_VAR_LIB_UPDATE_VARIABLE          UpdateVariable;
> +  PROTECTED_VAR_LIB_HOB_STORE_AVAILABLE
> IsHobVariableStoreAvailable;
> +} PROTECTED_VARIABLE_CONTEXT_IN;
> +
> +#pragma pack()
> +
> +/**
> +
> +  Initialization for protected variable services.
> +
> +  If this initialization failed upon any error, the whole variable services
> +  should not be used.  A system reset might be needed to re-construct NV
> +  variable storage to be the default state.
> +
> +  @param[in]  ContextIn   Pointer to variable service context needed by
> +                          protected variable.
> +
> +  @retval EFI_SUCCESS               Protected variable services are ready.
> +  @retval EFI_INVALID_PARAMETER     If ContextIn == NULL or something
> missing or
> +                                    mismatching in the content in ContextIn.
> +  @retval EFI_COMPROMISED_DATA      If failed to check integrity of protected
> variables.
> +  @retval EFI_OUT_OF_RESOURCES      Fail to allocate enough resource.
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibInitialize (
> +  IN  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn
> +  );
> +
> +/**
> +
> +  An alternative version of ProtectedVariableLibGetData to get plain data, if
> +  encrypted, from given variable, for different use cases.
> +
> +  @param[in,out]      VarInfo     Pointer to structure containing variable
> information.
> +
> +  @retval EFI_SUCCESS               Found the specified variable.
> +  @retval EFI_INVALID_PARAMETER     VarInfo is NULL or both VarInfo-
> >Address and
> +                                    VarInfo->Offset are invalid.
> +  @retval EFI_NOT_FOUND             The specified variable could not be found.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibGetByInfo (
> +  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
> +  );
> +
> +/**
> +  This service retrieves a variable's value using its name and GUID.
> +
> +  Read the specified variable from the UEFI variable store. If the Data
> +  buffer is too small to hold the contents of the variable, the error
> +  EFI_BUFFER_TOO_SMALL is returned and DataSize is set to the required buffer
> +  size to obtain the data.
> +
> +  @param  VariableName          A pointer to a null-terminated string that is the
> variable's name.
> +  @param  VariableGuid          A pointer to an EFI_GUID that is the variable's
> GUID. The combination of
> +                                VariableGuid and VariableName must be unique.
> +  @param  Attributes            If non-NULL, on return, points to the variable's
> attributes.
> +  @param  DataSize              On entry, points to the size in bytes of the Data
> buffer.
> +                                On return, points to the size of the data returned in Data.
> +  @param  Data                  Points to the buffer which will hold the returned
> variable value.
> +                                May be NULL with a zero DataSize in order to determine the
> size of the buffer needed.
> +
> +  @retval EFI_SUCCESS           The variable was read successfully.
> +  @retval EFI_NOT_FOUND         The variable was be found.
> +  @retval EFI_BUFFER_TOO_SMALL  The DataSize is too small for the resulting
> data.
> +                                DataSize is updated with the size required for
> +                                the specified variable.
> +  @retval EFI_INVALID_PARAMETER VariableName, VariableGuid, DataSize or
> Data is NULL.
> +  @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of
> a device error.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibGetByName (
> +  IN      CONST  CHAR16    *VariableName,
> +  IN      CONST  EFI_GUID  *VariableGuid,
> +  OUT UINT32               *Attributes,
> +  IN  OUT UINTN            *DataSize,
> +  OUT VOID                 *Data OPTIONAL
> +  );

[JianJW] The data type of parameters are not aligned.

> +
> +/**
> +
> +  Retrieve plain data, if encrypted, of given variable.
> +
> +  If variable encryption is employed, this function will initiate a SMM request
> +  to get the plain data. Due to security consideration, the decryption can only
> +  be done in SMM environment.
> +
> +  @param[in]      Variable           Pointer to header of a Variable.
> +  @param[out]     Data               Pointer to plain data of the given variable.
> +  @param[in, out] DataSize           Size of data returned or data buffer needed.
> +  @param[in]      AuthFlag           Auth-variable indicator.
> +
> +  @retval EFI_SUCCESS                Found the specified variable.
> +  @retval EFI_INVALID_PARAMETER      Invalid parameter.
> +  @retval EFI_NOT_FOUND              The specified variable could not be found.
> +  @retval EFI_BUFFER_TOO_SMALL       If *DataSize is smaller than needed.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibGetByBuffer (
> +  IN      VARIABLE_HEADER  *Variable,
> +  IN  OUT VOID             *Data,
> +  IN  OUT UINT32           *DataSize,
> +  IN      BOOLEAN          AuthFlag
> +  );
> +
> +/**
> +
> +  Prepare for variable update.
> +
> +  This is needed only once during current boot to mitigate replay attack. Its
> +  major job is to advance RPMC (Replay Protected Monotonic Counter).
> +
> +  @retval EFI_SUCCESS             Variable is ready to update hereafter.
> +  @retval EFI_UNSUPPORTED         Updating variable is not supported.
> +  @retval EFI_DEVICE_ERROR        Error in advancing RPMC.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibWriteInit (
> +  VOID
> +  );
> +
> +/**
> +
> +  Update a variable with protection provided by this library.
> +
> +  If variable encryption is employed, the new variable data will be encrypted
> +  before being written to NV variable storage.
> +
> +  A special variable, called "MetaDataHmacVar", will always be updated along
> +  with variable being updated to reflect the changes (HMAC value) of all
> +  protected valid variables. The only exceptions, currently, are variable
> +  "MetaDataHmacVar" itself and variable "VarErrorLog".
> +
> +  The buffer passed by NewVariable must be double of maximum variable size,
> +  which allows to pass the "MetaDataHmacVar" back to caller along with
> encrypted
> +  new variable data, if any. This can make sure the new variable data and
> +  "MetaDataHmacVar" can be written at almost the same time to reduce the
> chance
> +  of compromising the integrity.
> +
> +  If *NewVariableSize is zero, it means to delete variable passed by CurrVariable
> +  and/or CurrVariableInDel. "MetaDataHmacVar" will be updated as well in such
> +  case because of less variables in storage. NewVariable should be always
> passed
> +  in to convey new "MetaDataHmacVar" back.
> +
> +  @param[in,out]  CurrVariable        Variable to be updated. It's NULL if
> +                                      adding a new variable.
> +  @param[in,out]  CurrVariableInDel   In-delete-transition copy of updating
> variable.
> +  @param[in]      NewVariable         Buffer of new variable data.
> +  @param[out]     NewVariable         Buffer of "MetaDataHmacVar" and new
> +                                      variable (encrypted).
> +  @param[in]      NewVariableSize     Size of NewVariable.
> +  @param[out]     NewVariableSize     Size of (encrypted) NewVariable and
> +                                      "MetaDataHmacVar".
> +
> +  @retval EFI_SUCCESS             The variable is updated with protection
> successfully.
> +  @retval EFI_INVALID_PARAMETER   NewVariable is NULL.
> +  @retval EFI_NOT_FOUND           Information missing to finish the operation.
> +  @retval EFI_ABORTED             Failed to encrypt variable or calculate HMAC.
> +  @retval EFI_NOT_READY           The RPMC device is not yet initialized.
> +  @retval EFI_DEVICE_ERROR        The RPMC device has error in updating.
> +  @retval EFI_ACCESS_DENIED       The given variable is not allowed to update.
> +                                  Currently this only happens on updating
> +                                  "MetaDataHmacVar" from code outside of this
> +                                  library.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibUpdate (
> +  IN  OUT VARIABLE_HEADER  *CurrVariable OPTIONAL,
> +  IN  OUT VARIABLE_HEADER  *CurrVariableInDel OPTIONAL,
> +  IN  OUT VARIABLE_HEADER  *NewVariable,
> +  IN  OUT UINTN            *NewVariableSize
> +  );
> +
> +/**
> +
> +  Finalize a variable updating after it's written to NV variable storage
> +  successfully.
> +
> +  This usually includes works like increasing RPMC, synchronizing local cache,
> +  updating new position of "MetaDataHmacVar", deleting old copy of
> "MetaDataHmacVar"
> +  completely, etc.
> +
> +  @param[in]      NewVariable       Buffer of new variables and
> MetaDataHmacVar.
> +  @param[in]      VariableSize      Size of buffer pointed by NewVariable.
> +  @param[in]      Offset            Offset to NV variable storage from where the
> new

[JianJW] The "Offset" doesn't match the parameter name (StoreIndex) used in below

> +                                    variable and MetaDataHmacVar have been written.
> +
> +  @retval EFI_SUCCESS         No problem in winding up the variable write
> operation.
> +  @retval Others              Failed to updating state of old copy of updated
> +                              variable, or failed to increase RPMC, etc.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibWriteFinal (
> +  IN  VARIABLE_HEADER  *NewVariable,
> +  IN  UINTN            VariableSize,
> +  IN  UINT64           StoreIndex
> +  );
> +
> +/**
> +  Return the request variable name and GUID as per StoreIndex.
> +
> +  This function is called multiple times to retrieve the VariableName
> +  and VariableGuid of all variables currently available in the system.
> +  On each call, the previous results are passed into the interface,
> +  and, on return, the interface returns the data for the next
> +  interface. When the entire variable list has been returned,
> +  EFI_NOT_FOUND is returned.
> +
> +  @param  This              A pointer to this instance of the
> EFI_PEI_READ_ONLY_VARIABLE2_PPI.
> +
> +  @param  VariableNameSize  On entry, points to the size of the buffer pointed
> to by VariableName.
> +                            On return, the size of the variable name buffer.
> +  @param  VariableName      On entry, a pointer to a null-terminated string that
> is the variable's name.
> +                            On return, points to the next variable's null-terminated name
> string.
> +  @param  VariableGuid      On entry, a pointer to an EFI_GUID that is the
> variable's GUID.
> +                            On return, a pointer to the next variable's GUID.

[JianJW] The @param list doesn't match the real parameters declared below.

> +
> +  @retval EFI_SUCCESS           The variable was read successfully.
> +  @retval EFI_NOT_FOUND         The variable could not be found.
> +  @retval EFI_BUFFER_TOO_SMALL  The VariableNameSize is too small for the
> resulting
> +                                data. VariableNameSize is updated with the size
> +                                required for the specified variable.
> +  @retval EFI_INVALID_PARAMETER VariableName, VariableGuid or
> +                                VariableNameSize is NULL.
> +  @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of
> a device error.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibFind (
> +  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
> +  );
> +
> +/**
> +  Return the next variable name and GUID.
> +
> +  This function is called multiple times to retrieve the VariableName
> +  and VariableGuid of all variables currently available in the system.
> +  On each call, the previous results are passed into the interface,
> +  and, on return, the interface returns the data for the next
> +  interface. When the entire variable list has been returned,
> +  EFI_NOT_FOUND is returned.
> +
> +  @param  VariableNameSize  On entry, points to the size of the buffer pointed
> to by VariableName.
> +                            On return, the size of the variable name buffer.
> +  @param  VariableName      On entry, a pointer to a null-terminated string that
> is the variable's name.
> +                            On return, points to the next variable's null-terminated name
> string.
> +  @param  VariableGuid      On entry, a pointer to an EFI_GUID that is the
> variable's GUID.
> +                            On return, a pointer to the next variable's GUID.
> +
> +  @retval EFI_SUCCESS           The variable was read successfully.
> +  @retval EFI_NOT_FOUND         The variable could not be found.
> +  @retval EFI_BUFFER_TOO_SMALL  The VariableNameSize is too small for the
> resulting
> +                                data. VariableNameSize is updated with the size
> +                                required for the specified variable.
> +  @retval EFI_INVALID_PARAMETER VariableName, VariableGuid or
> +                                VariableNameSize is NULL.
> +  @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of
> a device error.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibFindNext (
> +  IN OUT UINTN     *VariableNameSize,
> +  IN OUT CHAR16    *VariableName,
> +  IN OUT EFI_GUID  *VariableGuid
> +  );
> +
> +/**
> +  Find variable via information in data structure PROTECTED_VARIABLE_INFO.
> +
> +   If VarInfo->StoreIndex is given and valid, always used it to search variable
> +   in store. Otherwise, search the variable via variable name and guid pointed
> +   by VarInfo->Header.VariableName and VarInfo->Header.VendorGuid.
> +
> +  @param VarInfo    Pointer to data containing variable information.
> +
> +  @return EFI_SUCCESS           Found the variable.
> +  @return EFI_INVALID_PARAMETER No valid variable information is given.
> +  @return EFI_NOT_FOUND         The given variable was not found or no more
> +                                variables available.
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibFindNextEx (
> +  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
> +  );
> +
> +/**
> +  Refresh variable information changed by variable service.
> +
> +  @param Variable         Pointer to buffer of the updated variable.
> +  @param VariableSize     Size of variable pointed by Variable.
> +  @param StoreIndex       New index of the variable in store.
> +  @param RefreshData      Flag to indicate if the variable has been updated.
> +
> +  @return EFI_SUCCESS     No error occurred in updating.
> +  @return EFI_NOT_FOUND   The given variable was not found in
> +                          ProtectedVariableLib.
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibRefresh (
> +  IN  VARIABLE_HEADER  *Variable,
> +  IN  UINTN            VariableSize,
> +  IN  UINT64           StoreIndex,
> +  IN  BOOLEAN          RefreshData
> +  );
> +
> +/**
> +  Refresh variable information changed by variable service.

[JianJW] This function description looks unmatching the function name.

> +
> +  @param Buffer           Pointer to a pointer of buffer.
> +  @param NumElements      Pointer to number of elements in list.
> +
> +
> +  @return EFI_SUCCESS     Successfully retrieved sorted list.
> +  @return others          Unsuccessful.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibGetSortedList (
> +  IN  OUT  EFI_PHYSICAL_ADDRESS  **Buffer,
> +  IN  OUT  UINTN                 *NumElements
> +  );
> +
> +/**
> +
> +  Determine if the variable is the HMAC variable
> +
> +  @param VariableName   Pointer to variable name.
> +
> +  @return TRUE      Variable is HMAC variable
> +  @return FALSE     Variable is not HMAC variable
> +
> +**/
> +BOOLEAN
> +ProtectedVariableLibIsHmac (
> +  IN CHAR16  *VariableName
> +  );
> +
> +#endif
> --
> 2.35.1.windows.2


^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [Patch v2 05/28] MdeModulePkg: Add new ProtectedVariable GUIDs
  2022-04-29 18:04 ` [Patch v2 05/28] MdeModulePkg: Add new ProtectedVariable GUIDs Judah Vang
@ 2022-05-12  9:32   ` Wang, Jian J
  0 siblings, 0 replies; 49+ messages in thread
From: Wang, Jian J @ 2022-05-12  9:32 UTC (permalink / raw)
  To: Vang, Judah, devel@edk2.groups.io; +Cc: Gao, Liming, Mistry, Nishant C

Reviewed-by: Jian J Wang <jian.j.wang@intel.com>

Regards,
Jian

> -----Original Message-----
> From: Vang, Judah <judah.vang@intel.com>
> Sent: Saturday, April 30, 2022 2:04 AM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Gao, Liming
> <gaoliming@byosoft.com.cn>; Mistry, Nishant C <nishant.c.mistry@intel.com>
> Subject: [Patch v2 05/28] MdeModulePkg: Add new ProtectedVariable GUIDs
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594
> 
> New ProtectVariable GUIDs for passing variable information
> from PEI phase to SMM phase.
> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Liming Gao <gaoliming@byosoft.com.cn>
> Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Judah Vang <judah.vang@intel.com>
> ---
>  MdeModulePkg/Include/Guid/ProtectedVariable.h | 22
> ++++++++++++++++++++
>  1 file changed, 22 insertions(+)
> 
> diff --git a/MdeModulePkg/Include/Guid/ProtectedVariable.h
> b/MdeModulePkg/Include/Guid/ProtectedVariable.h
> new file mode 100644
> index 000000000000..0c6e19e0456b
> --- /dev/null
> +++ b/MdeModulePkg/Include/Guid/ProtectedVariable.h
> @@ -0,0 +1,22 @@
> +/** @file
> +  The GUID definitions specific for protected variable services.
> +
> +Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
> +SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#ifndef PROTECTED_VARIABLE_H_
> +#define PROTECTED_VARIABLE_H_
> +
> +#define EDKII_PROTECTED_VARIABLE_GLOBAL_GUID \
> +  { 0x8ebf379a, 0xf18e, 0x4728, { 0xa4, 0x10, 0x0, 0xcf, 0x9a, 0x65, 0xbe,
> 0x91 } }
> +
> +#define EDKII_METADATA_HMAC_VARIABLE_GUID \
> +  { 0xb54cda50, 0xec54, 0x4b20, { 0x85, 0xb4, 0x57, 0xbf, 0x52, 0x98, 0x68,
> 0x3d } }
> +
> +extern EFI_GUID  gEdkiiProtectedVariableGlobalGuid;
> +extern EFI_GUID  gEdkiiMetaDataHmacVariableGuid;
> +extern EFI_GUID  gEdkiiProtectedVariableContextGuid;
> +
> +#endif // __PROTECTED_VARIABLE_H__
> --
> 2.35.1.windows.2


^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [Patch v2 04/28] MdeModulePkg: Add reference to new Ppi Guid
  2022-04-29 18:04 ` [Patch v2 04/28] MdeModulePkg: Add reference to new Ppi Guid Judah Vang
@ 2022-05-12  9:32   ` Wang, Jian J
  0 siblings, 0 replies; 49+ messages in thread
From: Wang, Jian J @ 2022-05-12  9:32 UTC (permalink / raw)
  To: Vang, Judah, devel@edk2.groups.io; +Cc: Gao, Liming, Mistry, Nishant C

Reviewed-by: Jian J Wang <jian.j.wang@intel.com>

Regards,
Jian

> -----Original Message-----
> From: Vang, Judah <judah.vang@intel.com>
> Sent: Saturday, April 30, 2022 2:04 AM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Gao, Liming
> <gaoliming@byosoft.com.cn>; Mistry, Nishant C <nishant.c.mistry@intel.com>
> Subject: [Patch v2 04/28] MdeModulePkg: Add reference to new Ppi Guid
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594
> 
> Add reference to gEfiPeiVariableStoreDiscoveredPpiGuid which
> contains information whether variable store is available.
> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Liming Gao <gaoliming@byosoft.com.cn>
> Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Judah Vang <judah.vang@intel.com>
> ---
>  MdePkg/Include/Ppi/ReadOnlyVariable2.h | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/MdePkg/Include/Ppi/ReadOnlyVariable2.h
> b/MdePkg/Include/Ppi/ReadOnlyVariable2.h
> index 926c0bc82a43..c5a8470565bb 100644
> --- a/MdePkg/Include/Ppi/ReadOnlyVariable2.h
> +++ b/MdePkg/Include/Ppi/ReadOnlyVariable2.h
> @@ -2,7 +2,7 @@
>    This file declares Read-only Variable Service2 PPI.
>    This ppi permits read-only access to the UEFI variable store during the PEI
> phase.
> 
> -Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>    @par Revision Reference:
> @@ -106,4 +106,6 @@ struct _EFI_PEI_READ_ONLY_VARIABLE2_PPI {
> 
>  extern EFI_GUID  gEfiPeiReadOnlyVariable2PpiGuid;
> 
> +extern EFI_GUID  gEfiPeiVariableStoreDiscoveredPpiGuid;
> +
>  #endif
> --
> 2.35.1.windows.2


^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [Patch v2 01/28] MdeModulePkg: Add new GUID for Variable Store Info
  2022-04-29 18:04 ` [Patch v2 01/28] MdeModulePkg: Add new GUID for Variable Store Info Judah Vang
@ 2022-05-12  9:32   ` Wang, Jian J
  0 siblings, 0 replies; 49+ messages in thread
From: Wang, Jian J @ 2022-05-12  9:32 UTC (permalink / raw)
  To: Vang, Judah, devel@edk2.groups.io; +Cc: Gao, Liming, Mistry, Nishant C

Reviewed-by: Jian J Wang <jian.j.wang@intel.com>

Regards,
Jian

> -----Original Message-----
> From: Vang, Judah <judah.vang@intel.com>
> Sent: Saturday, April 30, 2022 2:04 AM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Gao, Liming
> <gaoliming@byosoft.com.cn>; Mistry, Nishant C <nishant.c.mistry@intel.com>
> Subject: [Patch v2 01/28] MdeModulePkg: Add new GUID for Variable Store Info
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594
> 
> Discover if Variable Store Info HOB has been published
> by platform driver. It contains information in regards
> to HOB or NV Variable Store availability
> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Liming Gao <gaoliming@byosoft.com.cn>
> Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Judah Vang <judah.vang@intel.com>
> ---
>  MdeModulePkg/MdeModulePkg.dec | 13 ++++++++++++-
>  1 file changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/MdeModulePkg/MdeModulePkg.dec
> b/MdeModulePkg/MdeModulePkg.dec
> index cf79292ec877..f39827e4eacd 100644
> --- a/MdeModulePkg/MdeModulePkg.dec
> +++ b/MdeModulePkg/MdeModulePkg.dec
> @@ -4,7 +4,7 @@
>  # and libraries instances, which are used for those modules.
>  #
>  # Copyright (c) 2019, NVIDIA CORPORATION. All rights reserved.
> -# Copyright (c) 2007 - 2021, Intel Corporation. All rights reserved.<BR>
> +# Copyright (c) 2007 - 2022, Intel Corporation. All rights reserved.<BR>
>  # Copyright (c) 2016, Linaro Ltd. All rights reserved.<BR>
>  # (C) Copyright 2016 - 2019 Hewlett Packard Enterprise Development LP<BR>
>  # Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR>
> @@ -93,6 +93,14 @@ [LibraryClasses]
>    #
>    TpmMeasurementLib|Include/Library/TpmMeasurementLib.h
> 
> +  ## @libraryclass  Provides interfaces to encrypt/decrypt variable.
> +  #
> +  EncryptionVariableLib|Include/Library/EncryptionVariableLib.h
> +
> +  ## @libraryclass  Provides interfaces to encrypt/decrypt variable.
> +  #
> +  ProtectedVariableLib|Include/Library/ProtectedVariableLib.h
> +
>    ## @libraryclass  Provides authenticated variable services.
>    #
>    AuthVariableLib|Include/Library/AuthVariableLib.h
> @@ -505,6 +513,9 @@ [Ppis]
>    gEdkiiPeiCapsuleOnDiskPpiGuid             = { 0x71a9ea61, 0x5a35, 0x4a5d, { 0xac,
> 0xef, 0x9c, 0xf8, 0x6d, 0x6d, 0x67, 0xe0 } }
>    gEdkiiPeiBootInCapsuleOnDiskModePpiGuid   = { 0xb08a11e4, 0xe2b7, 0x4b75,
> { 0xb5, 0x15, 0xaf, 0x61, 0x6, 0x68, 0xbf, 0xd1  } }
> 
> +  ## Include/Ppi/ReadOnlyVariable2.h
> +  gEfiPeiVariableStoreDiscoveredPpiGuid     = { 0xa2fc038d, 0xfdf5, 0x4501,
> { 0xaf, 0x8e, 0x69, 0xb0, 0x20, 0xec, 0xe6, 0x63 } }
> +
>  [Protocols]
>    ## Load File protocol provides capability to load and unload EFI image into
> memory and execute it.
>    #  Include/Protocol/LoadPe32Image.h
> --
> 2.35.1.windows.2


^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [Patch v2 03/28] MdeModulePkg: Update AUTH_VARIABLE_INFO struct
  2022-04-29 18:04 ` [Patch v2 03/28] MdeModulePkg: Update AUTH_VARIABLE_INFO struct Judah Vang
@ 2022-05-12  9:33   ` Wang, Jian J
  0 siblings, 0 replies; 49+ messages in thread
From: Wang, Jian J @ 2022-05-12  9:33 UTC (permalink / raw)
  To: Vang, Judah, devel@edk2.groups.io; +Cc: Gao, Liming, Mistry, Nishant C

Reviewed-by: Jian J Wang <jian.j.wang@intel.com>

Regards,
Jian

> -----Original Message-----
> From: Vang, Judah <judah.vang@intel.com>
> Sent: Saturday, April 30, 2022 2:04 AM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Gao, Liming
> <gaoliming@byosoft.com.cn>; Mistry, Nishant C <nishant.c.mistry@intel.com>
> Subject: [Patch v2 03/28] MdeModulePkg: Update AUTH_VARIABLE_INFO struct
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594
> 
> Added NameSize and State to AUTH_VARIABLE_INFO struct.
> The size of the name and state is needed when creating
> the variable digest.
> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Liming Gao <gaoliming@byosoft.com.cn>
> Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Judah Vang <judah.vang@intel.com>
> ---
>  MdeModulePkg/Include/Library/AuthVariableLib.h | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/MdeModulePkg/Include/Library/AuthVariableLib.h
> b/MdeModulePkg/Include/Library/AuthVariableLib.h
> index 37aceba699e6..32391bbf2b61 100644
> --- a/MdeModulePkg/Include/Library/AuthVariableLib.h
> +++ b/MdeModulePkg/Include/Library/AuthVariableLib.h
> @@ -1,7 +1,7 @@
>  /** @file
>    Provides services to initialize and process authenticated variables.
> 
> -Copyright (c) 2015 - 2017, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2015 - 2022, Intel Corporation. All rights reserved.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> @@ -25,9 +25,11 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
>                                         (OFFSET_OF (WIN_CERTIFICATE_UEFI_GUID, CertData)))
> 
>  typedef struct {
> +  UINTN       NameSize;
>    CHAR16      *VariableName;
>    EFI_GUID    *VendorGuid;
>    UINT32      Attributes;
> +  UINT8       State;
>    UINTN       DataSize;
>    VOID        *Data;
>    UINT32      PubKeyIndex;
> --
> 2.35.1.windows.2


^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [Patch v2 02/28] SecurityPkg: Add new GUIDs for
  2022-04-29 18:04 ` [Patch v2 02/28] SecurityPkg: Add new GUIDs for Judah Vang
@ 2022-05-12  9:33   ` Wang, Jian J
  0 siblings, 0 replies; 49+ messages in thread
From: Wang, Jian J @ 2022-05-12  9:33 UTC (permalink / raw)
  To: Vang, Judah, devel@edk2.groups.io; +Cc: Yao, Jiewen, Mistry, Nishant C

Reviewed-by: Jian J Wang <jian.j.wang@intel.com>

Regards,
Jian

> -----Original Message-----
> From: Vang, Judah <judah.vang@intel.com>
> Sent: Saturday, April 30, 2022 2:04 AM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Yao, Jiewen <jiewen.yao@intel.com>;
> Mistry, Nishant C <nishant.c.mistry@intel.com>
> Subject: [Patch v2 02/28] SecurityPkg: Add new GUIDs for
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594
> 
> The gEdkiiProtectedVariableGlobalGuid HOB contains the global
> configuration data structure which is verified in PEI Phase.
> The gEdkiiMetaDataHmacVariableGuid is used for saving the
> meta data HMAC variable.
> The gEdkiiProtectedVariableContextGuid contains the Protected
> Variable context saved in PEI phase to be used later.
> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Judah Vang <judah.vang@intel.com>
> ---
>  SecurityPkg/SecurityPkg.dec | 43 +++++++++++++++++++-
>  1 file changed, 42 insertions(+), 1 deletion(-)
> 
> diff --git a/SecurityPkg/SecurityPkg.dec b/SecurityPkg/SecurityPkg.dec
> index 9f7a032d60d5..ea88908ea7d2 100644
> --- a/SecurityPkg/SecurityPkg.dec
> +++ b/SecurityPkg/SecurityPkg.dec
> @@ -5,7 +5,7 @@
>  #  It also provides the definitions(including PPIs/PROTOCOLs/GUIDs and library
> classes)
>  #  and libraries instances, which are used for those features.
>  #
> -# Copyright (c) 2009 - 2020, Intel Corporation. All rights reserved.<BR>
> +# Copyright (c) 2009 - 2022, Intel Corporation. All rights reserved.<BR>
>  # (C) Copyright 2015 Hewlett Packard Enterprise Development LP <BR>
>  # Copyright (c) Microsoft Corporation.<BR>
>  # SPDX-License-Identifier: BSD-2-Clause-Patent
> @@ -217,6 +217,18 @@ [Guids]
>    ## GUID used to specify section with default dbt content
>    gDefaultdbtFileGuid                = { 0x36c513ee, 0xa338, 0x4976, { 0xa0, 0xfb,
> 0x6d, 0xdb, 0xa3, 0xda, 0xfe, 0x87 } }
> 
> +  ## Include/Guid/ProtectedVariable.h
> +  # {8EBF379A-F18E-4728-A410-00CF9A65BE91}
> +  gEdkiiProtectedVariableGlobalGuid = { 0x8ebf379a, 0xf18e, 0x4728, { 0xa4,
> 0x10, 0x0, 0xcf, 0x9a, 0x65, 0xbe, 0x91 } }
> +
> +  ## Include/Guid/ProtectedVariable.h
> +  # {e3e890ad-5b67-466e-904f-94ca7e9376bb}
> +  gEdkiiMetaDataHmacVariableGuid = {0xe3e890ad, 0x5b67, 0x466e, {0x90,
> 0x4f, 0x94, 0xca, 0x7e, 0x93, 0x76, 0xbb}}
> +
> +  ## Include/Guid/ProtectedVariable.h
> +  # {a11a3652-875b-495a-b097-200917580b98}
> +  gEdkiiProtectedVariableContextGuid = {0xa11a3652, 0x875b, 0x495a, {0xb0,
> 0x97, 0x20, 0x09, 0x17, 0x58, 0x0b, 0x98} }
> +
>  [Ppis]
>    ## The PPI GUID for that TPM physical presence should be locked.
>    # Include/Ppi/LockPhysicalPresence.h
> @@ -242,6 +254,10 @@ [Ppis]
>    ## Include/Ppi/Tcg.h
>    gEdkiiTcgPpiGuid = {0x57a13b87, 0x133d, 0x4bf3, { 0xbf, 0xf1, 0x1b, 0xca,
> 0xc7, 0x17, 0x6c, 0xf1 } }
> 
> +  ## Key Service Ppi
> +  # Include/Ppi/KeyServicePpi.h
> +  gKeyServicePpiGuid = {0x583592f6, 0xEC34, 0x4CED, {0x8E, 0x81, 0xC8, 0xD1,
> 0x36, 0x93, 0x04, 0x27}}
> +
>  #
>  # [Error.gEfiSecurityPkgTokenSpaceGuid]
>  #   0x80000001 | Invalid value provided.
> @@ -325,6 +341,31 @@ [PcdsFixedAtBuild, PcdsPatchableInModule]
> 
> 
> gEfiSecurityPkgTokenSpaceGuid.PcdCpuRngSupportedAlgorithm|{0x00,0x00,0x0
> 0,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00}|VOID
> *|0x00010032
> 
> +  ## Progress Code for variable integrity check result.<BR><BR>
> +  #  DEFAULT: (EFI_PERIPHERAL_FIXED_MEDIA | [EFI_STATUS&0xFF])
> +  # @Prompt Status Code for variable integiry check result
> +
> gEfiSecurityPkgTokenSpaceGuid.PcdStatusCodeVariableIntegrity|0x01070000|U
> INT32|0x00010033
> +
> +  ## Null-terminated Unicode string of the Platform Variable Name
> +  # @Prompt known unprotected variable name
> +
> gEfiSecurityPkgTokenSpaceGuid.PcdPlatformVariableName|L""|VOID*|0x00010
> 034
> +
> +  ## Guid name to identify Platform Variable Guid
> +  # @Prompt known unprotected variable guid
> +  gEfiSecurityPkgTokenSpaceGuid.PcdPlatformVariableGuid|{ 0x00, 0x00, 0x00,
> 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> 0x00 }|VOID*|0x00010035
> +
> +  ## Defines Protected Variable Integrity support.
> +  #   TRUE  - Enable Protected Variable Integrity.<BR>
> +  #   FALSE - Disable Protected Variable Integrity.<BR>
> +  # @Prompt Protected Variable Integrity support.
> +
> gEfiSecurityPkgTokenSpaceGuid.PcdProtectedVariableIntegrity|FALSE|BOOLEA
> N|0x00010036
> +
> +  ## Defines Protected Variable Confidentiality support.
> +  #   TRUE  - Enable Protected Variable Confidentiality.<BR>
> +  #   FALSE - Disable Protected Variable Confidentiality.<BR>
> +  # @Prompt Protected Variable Integrity support.
> +
> gEfiSecurityPkgTokenSpaceGuid.PcdProtectedVariableConfidentiality|FALSE|BO
> OLEAN|0x00010037
> +
>  [PcdsFixedAtBuild, PcdsPatchableInModule, PcdsDynamic, PcdsDynamicEx]
>    ## Image verification policy for OptionRom. Only following values are
> valid:<BR><BR>
>    #  NOTE: Do NOT use 0x5 and 0x2 since it violates the UEFI specification and
> has been removed.<BR>
> --
> 2.35.1.windows.2


^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [edk2-devel] [Patch v2 00/28] UEFI variable protection
  2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
                   ` (27 preceding siblings ...)
  2022-04-29 18:04 ` [Patch v2 28/28] CryptoPkg: Enable cypto HMAC KDF library Judah Vang
@ 2022-05-17  2:48 ` Michael Kubacki
       [not found] ` <16EFC4965F71DFB8.20068@groups.io>
  29 siblings, 0 replies; 49+ messages in thread
From: Michael Kubacki @ 2022-05-17  2:48 UTC (permalink / raw)
  To: devel, judah.vang

Hi Judah,

Do you have reference information for the following?

1. Overall boot time impact for a sample variable store?

-  In particular:
   - Initial HMAC calculation/verification time.
   - Non-volatile write impact time to caluclate new store HMAC value 
and update MetaDataHmacVar.
   - Variable reclaim before and after time.

2. Overall non-volatile store size overhead impact with AES-CBC 
encrypted variables?

I understand these will vary based on system properties like SPI flash 
parameters, cryptographic processor details, etc. I'm trying to get an 
idea of the impact from sample data or averages on a particular system 
configuration. Also to learn whether the native encryption instruction 
(AES-NI) was used and if that could provide any benefit given the 
potential number of encryption/decryption operations introduced.

For the code design, I feel the ProtectedVariableLib interface is a bit 
too coupled against internal implementation details of the variable 
driver. I generally understand why the code is split out to wrap 
operations around the new functionality and it follows the AuthVarLib 
pattern but changing the library or driver will continue to require 
large changes across both like this due to the coupling.

Small things I noticed:
1. VariableKeyLib.inf should not be "BASE", it directly depends on PEI 
services
2. Typo "varabile" in some files
3. Does ProtectedVariableLibNull actually need to depend on BaseMemoryLib?

Thanks,
Michael

On 4/29/2022 2:04 PM, Judah Vang wrote:
> For a more detail description of the UEFI variable protected feature you can
> view the Readme.md located at the following location:
> https://github.com/judahvang/edk2/tree/rpmc-update
> 
> 
> Judah Vang (28):
>    MdeModulePkg: Add new GUID for Variable Store Info
>    SecurityPkg: Add new GUIDs for
>    MdeModulePkg: Update AUTH_VARIABLE_INFO struct
>    MdeModulePkg: Add reference to new Ppi Guid
>    MdeModulePkg: Add new ProtectedVariable GUIDs
>    MdeModulePkg: Add new include files
>    MdeModulePkg: Add Null ProtectedVariable Library
>    MdeModulePkg: Add new Variable functionality
>    MdeModulePkg: Add support for Protected Variables
>    SecurityPkg: Add new KeyService types and defines
>    SecurityPkg: Update RPMC APIs with index
>    SecurityPkg: Add new variable types and functions
>    SecurityPkg: Fix GetVariableKey API
>    SecurityPkg: Add null encryption variable libs
>    SecurityPkg: Add VariableKey library function
>    SecurityPkg: Add EncryptionVariable lib with AES
>    SecurityPkg: Add Protected Variable Services
>    MdeModulePkg: Reference Null ProtectedVariableLib
>    SecurityPkg: Add references to new *.inf files
>    ArmVirtPkg: Add reference to ProtectedVariableNull
>    UefiPayloadPkg: Add ProtectedVariable reference
>    EmulatorPkg: Add ProtectedVariable reference
>    OvmfPkg: Add ProtectedVariable reference
>    OvmfPkg: Add ProtectedVariableLib reference
>    OvmfPkg: Add ProtectedVariableLib reference
>    OvmfPkg: Add ProtectedVariableLib reference
>    OvmfPkg: Add ProtectedVariable reference
>    CryptoPkg: Enable cypto HMAC KDF library
> 
>   MdeModulePkg/MdeModulePkg.dec                                               |   13 +-
>   SecurityPkg/SecurityPkg.dec                                                 |   43 +-
>   ArmVirtPkg/ArmVirtQemu.dsc                                                  |    3 +-
>   EmulatorPkg/EmulatorPkg.dsc                                                 |    3 +-
>   MdeModulePkg/MdeModulePkg.dsc                                               |    4 +-
>   OvmfPkg/AmdSev/AmdSevX64.dsc                                                |    3 +-
>   OvmfPkg/Bhyve/BhyveX64.dsc                                                  |    3 +-
>   OvmfPkg/CloudHv/CloudHvX64.dsc                                              |    1 +
>   OvmfPkg/Microvm/MicrovmX64.dsc                                              |    3 +-
>   OvmfPkg/OvmfPkgIa32.dsc                                                     |    1 +
>   OvmfPkg/OvmfPkgIa32X64.dsc                                                  |    1 +
>   OvmfPkg/OvmfPkgX64.dsc                                                      |    1 +
>   OvmfPkg/OvmfXen.dsc                                                         |    3 +-
>   SecurityPkg/SecurityPkg.dsc                                                 |   13 +-
>   UefiPayloadPkg/UefiPayloadPkg.dsc                                           |    2 +
>   CryptoPkg/Library/BaseCryptLib/SmmCryptLib.inf                              |    2 +-
>   MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf  |   34 +
>   MdeModulePkg/Universal/Variable/Pei/VariablePei.inf                         |   10 +-
>   MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf           |    3 +-
>   MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf                  |    3 +-
>   MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.inf        |    4 +-
>   MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf         |    3 +-
>   SecurityPkg/Library/EncryptionVariableLib/EncryptionVariableLib.inf         |   43 +
>   SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf |   38 +
>   SecurityPkg/Library/ProtectedVariableLib/DxeProtectedVariableLib.inf        |   64 +
>   SecurityPkg/Library/ProtectedVariableLib/PeiProtectedVariableLib.inf        |   68 +
>   SecurityPkg/Library/ProtectedVariableLib/SmmProtectedVariableLib.inf        |   67 +
>   SecurityPkg/Library/ProtectedVariableLib/SmmRuntimeProtectedVariableLib.inf |   62 +
>   SecurityPkg/Library/VariableKeyLib/VariableKeyLib.inf                       |   36 +
>   MdeModulePkg/Include/Guid/ProtectedVariable.h                               |   22 +
>   MdeModulePkg/Include/Library/AuthVariableLib.h                              |    4 +-
>   MdeModulePkg/Include/Library/EncryptionVariableLib.h                        |  165 ++
>   MdeModulePkg/Include/Library/ProtectedVariableLib.h                         |  700 +++++++
>   MdeModulePkg/Universal/Variable/Pei/Variable.h                              |   80 +-
>   MdeModulePkg/Universal/Variable/Pei/VariableParsing.h                       |  309 +++
>   MdeModulePkg/Universal/Variable/Pei/VariableStore.h                         |  116 ++
>   MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h                       |  126 +-
>   MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.h                |   91 +-
>   MdePkg/Include/Ppi/ReadOnlyVariable2.h                                      |    4 +-
>   SecurityPkg/Include/Library/RpmcLib.h                                       |   15 +-
>   SecurityPkg/Include/Library/VariableKeyLib.h                                |   37 +-
>   SecurityPkg/Include/Ppi/KeyServicePpi.h                                     |   57 +
>   SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.h              |   49 +
>   SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableInternal.h        |  611 ++++++
>   MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariable.c           |  449 ++++
>   MdeModulePkg/Universal/Variable/Pei/Variable.c                              |  886 ++------
>   MdeModulePkg/Universal/Variable/Pei/VariableParsing.c                       |  941 +++++++++
>   MdeModulePkg/Universal/Variable/Pei/VariableStore.c                         |  305 +++
>   MdeModulePkg/Universal/Variable/RuntimeDxe/Reclaim.c                        |  349 +++-
>   MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c                       | 2139 +++++++++++---------
>   MdeModulePkg/Universal/Variable/RuntimeDxe/VariableDxe.c                    |   26 +-
>   MdeModulePkg/Universal/Variable/RuntimeDxe/VariableExLib.c                  |  167 +-
>   MdeModulePkg/Universal/Variable/RuntimeDxe/VariableNonVolatile.c            |  194 +-
>   MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.c                |  320 ++-
>   MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeCache.c           |    2 +-
>   MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c                    |   39 +-
>   MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.c          |   41 +-
>   SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.c              |  728 +++++++
>   SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariable.c          |  107 +
>   SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableCommon.c          | 2095 +++++++++++++++++++
>   SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableDxe.c             |  163 ++
>   SecurityPkg/Library/ProtectedVariableLib/ProtectedVariablePei.c             | 1331 ++++++++++++
>   SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmm.c             |  209 ++
>   SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmDxeCommon.c    |  975 +++++++++
>   SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmRuntime.c      |  233 +++
>   SecurityPkg/Library/RpmcLibNull/RpmcLibNull.c                               |    8 +-
>   SecurityPkg/Library/VariableKeyLib/VariableKeyLib.c                         |   59 +
>   SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.c                 |    6 +-
>   SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.uni |   16 +
>   69 files changed, 12845 insertions(+), 1863 deletions(-)
>   create mode 100644 MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
>   create mode 100644 SecurityPkg/Library/EncryptionVariableLib/EncryptionVariableLib.inf
>   create mode 100644 SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf
>   create mode 100644 SecurityPkg/Library/ProtectedVariableLib/DxeProtectedVariableLib.inf
>   create mode 100644 SecurityPkg/Library/ProtectedVariableLib/PeiProtectedVariableLib.inf
>   create mode 100644 SecurityPkg/Library/ProtectedVariableLib/SmmProtectedVariableLib.inf
>   create mode 100644 SecurityPkg/Library/ProtectedVariableLib/SmmRuntimeProtectedVariableLib.inf
>   create mode 100644 SecurityPkg/Library/VariableKeyLib/VariableKeyLib.inf
>   create mode 100644 MdeModulePkg/Include/Guid/ProtectedVariable.h
>   create mode 100644 MdeModulePkg/Include/Library/EncryptionVariableLib.h
>   create mode 100644 MdeModulePkg/Include/Library/ProtectedVariableLib.h
>   create mode 100644 MdeModulePkg/Universal/Variable/Pei/VariableParsing.h
>   create mode 100644 MdeModulePkg/Universal/Variable/Pei/VariableStore.h
>   create mode 100644 SecurityPkg/Include/Ppi/KeyServicePpi.h
>   create mode 100644 SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.h
>   create mode 100644 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableInternal.h
>   create mode 100644 MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariable.c
>   create mode 100644 MdeModulePkg/Universal/Variable/Pei/VariableParsing.c
>   create mode 100644 MdeModulePkg/Universal/Variable/Pei/VariableStore.c
>   create mode 100644 SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.c
>   create mode 100644 SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariable.c
>   create mode 100644 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableCommon.c
>   create mode 100644 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableDxe.c
>   create mode 100644 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariablePei.c
>   create mode 100644 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmm.c
>   create mode 100644 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmDxeCommon.c
>   create mode 100644 SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmRuntime.c
>   create mode 100644 SecurityPkg/Library/VariableKeyLib/VariableKeyLib.c
>   create mode 100644 SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.uni
> 

^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [Patch v2 07/28] MdeModulePkg: Add Null ProtectedVariable Library
  2022-04-29 18:04 ` [Patch v2 07/28] MdeModulePkg: Add Null ProtectedVariable Library Judah Vang
@ 2022-05-22  8:38   ` Wang, Jian J
  0 siblings, 0 replies; 49+ messages in thread
From: Wang, Jian J @ 2022-05-22  8:38 UTC (permalink / raw)
  To: Vang, Judah, devel@edk2.groups.io; +Cc: Gao, Liming, Mistry, Nishant C

Judah,

Following interface has no non-Null version implemented.
Consider removing them completely.

ProtectedVariableLibGetStore()
ProtectedVariableLibReclaim()
ProtectedVariableLibGetDataInfo()
ProtectedVariableLibGetNextEx()
ProtectedVariableLibGetNext ()

Regards,
Jian

> -----Original Message-----
> From: Vang, Judah <judah.vang@intel.com>
> Sent: Saturday, April 30, 2022 2:04 AM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Gao, Liming
> <gaoliming@byosoft.com.cn>; Mistry, Nishant C <nishant.c.mistry@intel.com>
> Subject: [Patch v2 07/28] MdeModulePkg: Add Null ProtectedVariable Library
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594
> 
> Add Null versions of the ProtectedVariable Library.
> This will be the default libraries for platforms that
> do not support ProtectedVariable.
> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Liming Gao <gaoliming@byosoft.com.cn>
> Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Judah Vang <judah.vang@intel.com>
> ---
>  MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf
> |  34 ++
>  MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariable.c          |
> 449 ++++++++++++++++++++
>  2 files changed, 483 insertions(+)
> 
> diff --git
> a/MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.in
> f
> b/MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.in
> f
> new file mode 100644
> index 000000000000..6a17191c4e1e
> --- /dev/null
> +++
> b/MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.in
> f
> @@ -0,0 +1,34 @@
> +## @file
> +#  Provides null version of protected variable services.
> +#
> +#  Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
> +#  SPDX-License-Identifier: BSD-2-Clause-Patent
> +#
> +##
> +
> +[Defines]
> +  INF_VERSION                    = 0x00010029
> +  BASE_NAME                      = ProtectedVariableLibNull
> +  FILE_GUID                      = 352C6A1B-403A-4E37-8517-FAA50BC45251
> +  MODULE_TYPE                    = BASE
> +  VERSION_STRING                 = 0.1
> +  LIBRARY_CLASS                  = ProtectedVariableLib
> +
> +#
> +# The following information is for reference only and not required by the build
> tools.
> +#
> +#  VALID_ARCHITECTURES           = IA32 X64
> +#
> +
> +[Sources]
> +  ProtectedVariable.c
> +
> +[Packages]
> +  MdePkg/MdePkg.dec
> +  MdeModulePkg/MdeModulePkg.dec
> +
> +[LibraryClasses]
> +  BaseLib
> +  BaseMemoryLib
> +  DebugLib
> +
> diff --git
> a/MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariable.c
> b/MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariable.c
> new file mode 100644
> index 000000000000..cc1e16c1a671
> --- /dev/null
> +++ b/MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariable.c
> @@ -0,0 +1,449 @@
> +/** @file
> +  NULL version of ProtectedVariableLib used to disable protected variable
> services.
> +
> +Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
> +SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#include <PiDxe.h>
> +#include <Uefi.h>
> +
> +#include <Library/DebugLib.h>
> +#include <Library/BaseMemoryLib.h>
> +#include <Library/ProtectedVariableLib.h>
> +
> +/**
> +
> +  Initialization for protected varibale services.
> +
> +  @param[in]  ContextIn   Pointer to variable service context needed by
> +                          protected variable.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibInitialize (
> +  IN  PROTECTED_VARIABLE_CONTEXT_IN  *ContextIn
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Get a verified copy of NV variable storage.
> +
> +  @param[out]     VariableFvHeader      Pointer to the header of whole NV
> firmware volume.
> +  @param[out]     VariableStoreHeader   Pointer to the header of variable
> storage.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibGetStore (
> +  OUT EFI_FIRMWARE_VOLUME_HEADER  **VariableFvHeader,
> +  OUT VARIABLE_STORE_HEADER       **VariableStoreHeader
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Prepare for variable update.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibWriteInit (
> +  VOID
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Update a variable with protection provided by this library.
> +
> +  @param[in,out]  CurrVariable        Variable to be updated. It's NULL if
> +                                      adding a new variable.
> +  @param[in]      CurrVariableInDel   In-delete-transiion copy of updating
> variable.
> +  @param[in,out]  NewVariable         Buffer of new variable data.
> +                                      Buffer of "MetaDataHmacVar" and new
> +                                      variable (encrypted).
> +  @param[in,out]  NewVariableSize     Size of NewVariable.
> +                                      Size of (encrypted) NewVariable and
> +                                      "MetaDataHmacVar".
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibUpdate (
> +  IN  OUT VARIABLE_HEADER  *CurrVariable,
> +  IN      VARIABLE_HEADER  *CurrVariableInDel,
> +  IN  OUT VARIABLE_HEADER  *NewVariable,
> +  IN  OUT UINTN            *NewVariableSize
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Finalize a variable updating after it's written to NV variable storage
> +  successfully.
> +
> +  @param[in]      NewVariable       Buffer of new variables and
> MetaDataHmacVar.
> +  @param[in]      VariableSize      Size of buffer pointed by NewVariable.
> +  @param[in]      StoreIndex        New index of the variable in store.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibWriteFinal (
> +  IN  VARIABLE_HEADER  *NewVariable,
> +  IN  UINTN            VariableSize,
> +  IN  UINT64           StoreIndex
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Perform garbage collection against the cached copy of NV variable storage.
> +
> +  @param[in]      VariableStoreBuffer         Buffer used to do the reclaim.
> +  @param[out]     LastVariableOffset          New free space start point.
> +  @param[in]      CurrVariableOffset          Offset of existing variable.
> +  @param[in]      CurrVariableInDelOffset     Offset of old copy of existing
> variable.
> +  @param[in,out]  NewVariable                 Buffer of new variable data.
> +  @param[in]      NewVariableSize             Size of new variable data.
> +  @param[in,out]  HwErrVariableTotalSize      Total size of variables with HR
> attribute.
> +  @param[in,out]  CommonVariableTotalSize     Total size of common variables.
> +  @param[in,out]  CommonUserVariableTotalSize Total size of user variables.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibReclaim (
> +  IN      VARIABLE_STORE_HEADER  *VariableStoreBuffer,
> +  OUT     UINTN                  *LastVariableOffset,
> +  IN      UINTN                  CurrVariableOffset,
> +  IN      UINTN                  CurrVariableInDelOffset,
> +  IN  OUT VARIABLE_HEADER        **NewVariable,
> +  IN      UINTN                  NewVariableSize,
> +  IN  OUT UINTN                  *HwErrVariableTotalSize,
> +  IN  OUT UINTN                  *CommonVariableTotalSize,
> +  IN  OUT UINTN                  *CommonUserVariableTotalSize
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  An alternative version of ProtectedVariableLibGetData to get plain data, if
> +  encrypted, from given variable, for different use cases.
> +
> +  @param[in,out]      VarInfo     Pointer to structure containing variable
> information.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibGetDataInfo (
> +  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Retrieve plain data, if encrypted, of given variable.
> +
> +  @param[in]      Variable           Pointer to header of a Variable.
> +  @param[in,out]  Data               Pointer to plain data of the given variable.
> +  @param[in,out]  DataSize           Size of data returned or data buffer needed.
> +  @param[in]      AuthFlag           Auth-variable indicator.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibGetData (
> +  IN      VARIABLE_HEADER  *Variable,
> +  IN  OUT VOID             *Data,
> +  IN  OUT UINT32           *DataSize,
> +  IN      BOOLEAN          AuthFlag
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Retrieve next protected variable stub.
> +
> +  @param[in,out]      VarInfo     Pointer to structure containing variable
> information.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibGetNextEx (
> +  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Retrieve next protected variable.
> +
> +  @param[in,out]      VariableNameSize    Pointer to size of variable name.
> +  @param[in,out]      VariableName        Pointer to variable name.
> +  @param[in,out]      VariableGuid        Pointer to vairable GUID.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibGetNext (
> +  IN OUT UINTN     *VariableNameSize,
> +  IN OUT CHAR16    *VariableName,
> +  IN OUT EFI_GUID  *VariableGuid
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Get the specified protected variable.
> +
> +  @param[in]      VariableName      Pointer to variable name.
> +  @param[in]      VariableGuid      Pointer to vairable GUID.
> +  @param[out]     Attributes        Pointer to attributes.
> +  @param[in,out]  DataSize          Pointer to data size.
> +  @param[out]     Data              Pointer to data.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibGet (
> +  IN      CONST  CHAR16    *VariableName,
> +  IN      CONST  EFI_GUID  *VariableGuid,
> +  OUT UINT32               *Attributes,
> +  IN  OUT UINTN            *DataSize,
> +  OUT VOID                 *Data OPTIONAL
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Find the protected variable.
> +
> +  @param[in,out]      VarInfo     Pointer to structure containing variable
> information.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibFind (
> +  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Find next protected variable.
> +
> +  @param[in,out]      VariableNameSize    Pointer to size of variable name.
> +  @param[in,out]      VariableName        Pointer to variable name.
> +  @param[in,out]      VariableGuid        Pointer to vairable GUID.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibFindNext (
> +  IN OUT UINTN     *VariableNameSize,
> +  IN OUT CHAR16    *VariableName,
> +  IN OUT EFI_GUID  *VariableGuid
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Find next protected variable stub.
> +
> +  @param[in,out]      VarInfo     Pointer to structure containing variable
> information.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibFindNextEx (
> +  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Get protected variable by information.
> +
> +  @param[in,out]      VarInfo     Pointer to structure containing variable
> information.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibGetByInfo (
> +  IN  OUT PROTECTED_VARIABLE_INFO  *VarInfo
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Get protected variable by name.
> +
> +  @param[in]      VariableName      Pointer to variable name.
> +  @param[in]      VariableGuid      Pointer to vairable GUID.
> +  @param[out]     Attributes        Pointer to attributes.
> +  @param[in,out]  DataSize          Pointer to data size.
> +  @param[out]     Data              Pointer to data.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibGetByName (
> +  IN      CONST  CHAR16    *VariableName,
> +  IN      CONST  EFI_GUID  *VariableGuid,
> +  OUT UINT32               *Attributes,
> +  IN  OUT UINTN            *DataSize,
> +  OUT VOID                 *Data OPTIONAL
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Get protected variable by name.
> +
> +  @param[in]      Variable      Pointer to variable name.
> +  @param[in,out]  Data          Pointer to variable data.
> +  @param[in,out]  DataSize      Pointer to data size.
> +  @param[in]      AuthFlag      Authenticate flag.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibGetByBuffer (
> +  IN      VARIABLE_HEADER  *Variable,
> +  IN  OUT VOID             *Data,
> +  IN  OUT UINT32           *DataSize,
> +  IN      BOOLEAN          AuthFlag
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +  Refresh variable information changed by variable service.
> +
> +  @param[in]  Variable         Pointer to buffer of the updated variable.
> +  @param[in]  VariableSize     Size of variable pointed by Variable.
> +  @param[in]  StoreIndex       New index of the variable in store.
> +  @param[in]  RefreshData      Flag to indicate if the variable has been updated.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibRefresh (
> +  IN  VARIABLE_HEADER  *Variable,
> +  IN  UINTN            VariableSize,
> +  IN  UINT64           StoreIndex,
> +  IN  BOOLEAN          RefreshData
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Get sorted protected variable list.
> +
> +  @param[in,out]  Buffer        Pointer to buffer.
> +  @param[in,out]  NumElements   Pointer to number of elements.
> +
> +  @retval EFI_UNSUPPORTED           Unsupported to process protected variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +ProtectedVariableLibGetSortedList (
> +  IN  OUT  EFI_PHYSICAL_ADDRESS  **Buffer,
> +  IN  OUT  UINTN                 *NumElements
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +
> +  Determine if the variable is the HMAC variable.
> +
> +  @param[in]  VariableName   Pointer to variable name.
> +
> +  @return FALSE     Variable is not HMAC variable
> +
> +**/
> +BOOLEAN
> +ProtectedVariableLibIsHmac (
> +  IN CHAR16  *VariableName
> +  )
> +{
> +  return FALSE;
> +}
> --
> 2.35.1.windows.2


^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [Patch v2 08/28] MdeModulePkg: Add new Variable functionality
  2022-04-29 18:04 ` [Patch v2 08/28] MdeModulePkg: Add new Variable functionality Judah Vang
@ 2022-05-22 10:24   ` Wang, Jian J
  0 siblings, 0 replies; 49+ messages in thread
From: Wang, Jian J @ 2022-05-22 10:24 UTC (permalink / raw)
  To: Vang, Judah, devel@edk2.groups.io; +Cc: Gao, Liming, Mistry, Nishant C

Judah,

One general comment: please add variable store provision/recovery flow and
explanations in the readme.

See my other inline comments below.

Regards,
Jian

> -----Original Message-----
> From: Vang, Judah <judah.vang@intel.com>
> Sent: Saturday, April 30, 2022 2:04 AM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Gao, Liming
> <gaoliming@byosoft.com.cn>; Mistry, Nishant C <nishant.c.mistry@intel.com>
> Subject: [Patch v2 08/28] MdeModulePkg: Add new Variable functionality
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594
> 
> Provide new APIs for retrieving variable information.
> Add new function stubs for retrieving Protected
> variable information.
> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Liming Gao <gaoliming@byosoft.com.cn>
> Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Judah Vang <judah.vang@intel.com>
> ---
>  MdeModulePkg/Universal/Variable/Pei/VariablePei.inf   |  10 +-
>  MdeModulePkg/Universal/Variable/Pei/Variable.h        |  80 +-
>  MdeModulePkg/Universal/Variable/Pei/VariableParsing.h | 309 +++++++
>  MdeModulePkg/Universal/Variable/Pei/VariableStore.h   | 116 +++
>  MdeModulePkg/Universal/Variable/Pei/Variable.c        | 886 +++---------------
>  MdeModulePkg/Universal/Variable/Pei/VariableParsing.c | 941
> ++++++++++++++++++++
>  MdeModulePkg/Universal/Variable/Pei/VariableStore.c   | 305 +++++++
>  7 files changed, 1891 insertions(+), 756 deletions(-)
> 
> diff --git a/MdeModulePkg/Universal/Variable/Pei/VariablePei.inf
> b/MdeModulePkg/Universal/Variable/Pei/VariablePei.inf
> index 7cbdd2385e8f..af172126a011 100644
> --- a/MdeModulePkg/Universal/Variable/Pei/VariablePei.inf
> +++ b/MdeModulePkg/Universal/Variable/Pei/VariablePei.inf
> @@ -3,7 +3,7 @@
>  #
>  #  This module implements ReadOnly Variable Services required by PEIM and
> installs PEI ReadOnly Varaiable2 PPI.
>  #
> -#  Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
> +#  Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
>  #  SPDX-License-Identifier: BSD-2-Clause-Patent
>  #
>  ##
> @@ -26,6 +26,10 @@ [Defines]
>  [Sources]
>    Variable.c
>    Variable.h
> +  VariableStore.c
> +  VariableStore.h
> +  VariableParsing.c
> +  VariableParsing.h
> 
>  [Packages]
>    MdePkg/MdePkg.dec
> @@ -39,6 +43,7 @@ [LibraryClasses]
>    DebugLib
>    PeiServicesTablePointerLib
>    PeiServicesLib
> +  ProtectedVariableLib
> 
>  [Guids]
>    ## CONSUMES             ## GUID # Variable store header
> @@ -56,7 +61,8 @@ [Guids]
>    gEdkiiFaultTolerantWriteGuid
> 
>  [Ppis]
> -  gEfiPeiReadOnlyVariable2PpiGuid   ## PRODUCES
> +  gEfiPeiReadOnlyVariable2PpiGuid        ## PRODUCES
> +  gEfiPeiVariableStoreDiscoveredPpiGuid  ## CONSUMES
> 
>  [Pcd]
>    gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageVariableBase      ##
> SOMETIMES_CONSUMES
> diff --git a/MdeModulePkg/Universal/Variable/Pei/Variable.h
> b/MdeModulePkg/Universal/Variable/Pei/Variable.h
> index 7f9ad5bfc357..115426edd626 100644
> --- a/MdeModulePkg/Universal/Variable/Pei/Variable.h
> +++ b/MdeModulePkg/Universal/Variable/Pei/Variable.h
> @@ -2,7 +2,7 @@
>    The internal header file includes the common header files, defines
>    internal structure and functions used by PeiVariable module.
> 
> -Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> @@ -20,11 +20,13 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
>  #include <Library/BaseMemoryLib.h>
>  #include <Library/PeiServicesTablePointerLib.h>
>  #include <Library/PeiServicesLib.h>
> +#include <Library/ProtectedVariableLib.h>
> 
>  #include <Guid/VariableFormat.h>
>  #include <Guid/VariableIndexTable.h>
>  #include <Guid/SystemNvDataGuid.h>
>  #include <Guid/FaultTolerantWrite.h>
> +#include <Guid/ProtectedVariable.h>
> 
>  typedef enum {
>    VariableStoreTypeHob,
> @@ -142,4 +144,80 @@ PeiGetNextVariableName (
>    IN OUT EFI_GUID                            *VariableGuid
>    );
> 
> +/**
> +  This service retrieves a variable's value using its name and GUID.
> +
> +  Read the specified variable from the UEFI variable store. If the Data
> +  buffer is too small to hold the contents of the variable, the error
> +  EFI_BUFFER_TOO_SMALL is returned and DataSize is set to the required buffer
> +  size to obtain the data.
> +
> +  @param  This                  A pointer to this instance of the
> EFI_PEI_READ_ONLY_VARIABLE2_PPI.
> +  @param  VariableName          A pointer to a null-terminated string that is the
> variable's name.
> +  @param  VariableGuid          A pointer to an EFI_GUID that is the variable's
> GUID. The combination of
> +                                VariableGuid and VariableName must be unique.
> +  @param  Attributes            If non-NULL, on return, points to the variable's
> attributes.
> +  @param  DataSize              On entry, points to the size in bytes of the Data
> buffer.
> +                                On return, points to the size of the data returned in Data.
> +  @param  Data                  Points to the buffer which will hold the returned
> variable value.
> +                                May be NULL with a zero DataSize in order to determine the
> size of the buffer needed.
> +
> +  @retval EFI_SUCCESS           The variable was read successfully.
> +  @retval EFI_NOT_FOUND         The variable was not found.
> +  @retval EFI_BUFFER_TOO_SMALL  The DataSize is too small for the resulting
> data.
> +                                DataSize is updated with the size required for
> +                                the specified variable.
> +  @retval EFI_INVALID_PARAMETER VariableName, VariableGuid, DataSize or
> Data is NULL.
> +  @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of
> a device error.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +PeiGetVariableEx (
> +  IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI  *This,
> +  IN CONST  CHAR16                           *VariableName,
> +  IN CONST  EFI_GUID                         *VariableGuid,
> +  OUT       UINT32                           *Attributes,
> +  IN OUT    UINTN                            *DataSize,
> +  OUT       VOID                             *Data OPTIONAL
> +  );
> +
> +/**
> +  Return the next variable name and GUID.
> +
> +  This function is called multiple times to retrieve the VariableName
> +  and VariableGuid of all variables currently available in the system.
> +  On each call, the previous results are passed into the interface,
> +  and, on return, the interface returns the data for the next
> +  interface. When the entire variable list has been returned,
> +  EFI_NOT_FOUND is returned.
> +
> +  @param  This              A pointer to this instance of the
> EFI_PEI_READ_ONLY_VARIABLE2_PPI.
> +
> +  @param  VariableNameSize  On entry, points to the size of the buffer pointed
> to by VariableName.
> +  @param  VariableName      On entry, a pointer to a null-terminated string that
> is the variable's name.
> +                            On return, points to the next variable's null-terminated name
> string.
> +
> +  @param  VariableGuid      On entry, a pointer to an UEFI _GUID that is the
> variable's GUID.
> +                            On return, a pointer to the next variable's GUID.
> +
> +  @retval EFI_SUCCESS           The variable was read successfully.
> +  @retval EFI_NOT_FOUND         The variable could not be found.
> +  @retval EFI_BUFFER_TOO_SMALL  The VariableNameSize is too small for the
> resulting
> +                                data. VariableNameSize is updated with the size
> +                                required for the specified variable.
> +  @retval EFI_INVALID_PARAMETER VariableName, VariableGuid or
> +                                VariableNameSize is NULL.
> +  @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of
> a device error.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +PeiGetNextVariableNameEx (
> +  IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI  *This,
> +  IN OUT UINTN                               *VariableNameSize,
> +  IN OUT CHAR16                              *VariableName,
> +  IN OUT EFI_GUID                            *VariableGuid
> +  );
> +
>  #endif
> diff --git a/MdeModulePkg/Universal/Variable/Pei/VariableParsing.h
> b/MdeModulePkg/Universal/Variable/Pei/VariableParsing.h
> new file mode 100644
> index 000000000000..d7af6cb6e8be
> --- /dev/null
> +++ b/MdeModulePkg/Universal/Variable/Pei/VariableParsing.h
> @@ -0,0 +1,309 @@
> +/** @file
> +  The internal header file includes the common header files, defines
> +  internal structure and functions used by PeiVariable module.
> +
> +Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
> +SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#ifndef PEI_VARIABLE_PARSING_H_
> +#define PEI_VARIABLE_PARSING_H_
> +
> +#include "Variable.h"
> +
> +/**
> +
> +  Gets the pointer to the first variable header in given variable store area.
> +
> +  @param[in] VarStoreHeader  Pointer to the Variable Store Header.
> +
> +  @return Pointer to the first variable header.
> +
> +**/
> +VARIABLE_HEADER *
> +GetStartPointer (
> +  IN VARIABLE_STORE_HEADER  *VarStoreHeader
> +  );
> +
> +/**
> +
> +  Gets the pointer to the end of the variable storage area.
> +
> +  This function gets pointer to the end of the variable storage
> +  area, according to the input variable store header.
> +
> +  @param[in] VarStoreHeader  Pointer to the Variable Store Header.
> +
> +  @return Pointer to the end of the variable storage area.
> +
> +**/
> +VARIABLE_HEADER *
> +GetEndPointer (
> +  IN VARIABLE_STORE_HEADER  *VarStoreHeader
> +  );
> +
> +/**
> +  This code checks if variable header is valid or not.
> +
> +  @param[in]  Variable  Pointer to the Variable Header.
> +
> +  @retval TRUE      Variable header is valid.
> +  @retval FALSE     Variable header is not valid.
> +
> +**/
> +BOOLEAN
> +IsValidVariableHeader (
> +  IN  VARIABLE_HEADER  *Variable
> +  );
> +
> +/**
> +  This code gets the pointer to the next variable header.
> +
> +  @param[in]  StoreInfo         Pointer to variable store info structure.
> +  @param[in]  Variable          Pointer to the Variable Header.
> +  @param[in]  VariableHeader    Pointer to the Variable Header that has
> consecutive content.
> +
> +  @return  A VARIABLE_HEADER* pointer to next variable header.
> +
> +**/
> +VARIABLE_HEADER *
> +GetNextVariablePtr (
> +  IN  VARIABLE_STORE_INFO  *StoreInfo,
> +  IN  VARIABLE_HEADER      *Variable,
> +  IN  VARIABLE_HEADER      *VariableHeader
> +  );
> +
> +/**
> +  This code gets the pointer to the variable guid.
> +
> +  @param[in]  Variable   Pointer to the Variable Header.
> +  @param[in]  AuthFlag   Authenticated variable flag.
> +
> +  @return A EFI_GUID* pointer to Vendor Guid.
> +
> +**/
> +EFI_GUID *
> +GetVendorGuidPtr (
> +  IN VARIABLE_HEADER  *Variable,
> +  IN BOOLEAN          AuthFlag
> +  );
> +
> +/**
> +  This code gets the pointer to the variable name.
> +
> +  @param[in]   Variable  Pointer to the Variable Header.
> +  @param[in]   AuthFlag  Authenticated variable flag.
> +
> +  @return  A CHAR16* pointer to Variable Name.
> +
> +**/
> +CHAR16 *
> +GetVariableNamePtr (
> +  IN VARIABLE_HEADER  *Variable,
> +  IN BOOLEAN          AuthFlag
> +  );
> +
> +/**
> +  This code gets the size of name of variable.
> +
> +  @param[in]  Variable  Pointer to the Variable Header.
> +  @param[in]  AuthFlag  Authenticated variable flag.
> +
> +  @return Size of variable in bytes in type UINTN.
> +
> +**/
> +UINTN
> +NameSizeOfVariable (
> +  IN  VARIABLE_HEADER  *Variable,
> +  IN  BOOLEAN          AuthFlag
> +  );
> +
> +/**
> +  This code gets the size of data of variable.
> +
> +  @param[in]  Variable  Pointer to the Variable Header.
> +  @param[in]  AuthFlag  Authenticated variable flag.
> +
> +  @return Size of variable in bytes in type UINTN.
> +
> +**/
> +UINTN
> +DataSizeOfVariable (
> +  IN  VARIABLE_HEADER  *Variable,
> +  IN  BOOLEAN          AuthFlag
> +  );
> +
> +/**
> +  This code gets the pointer to the variable data.
> +
> +  @param[in]   Variable         Pointer to the Variable Header.
> +  @param[in]   VariableHeader   Pointer to the Variable Header that has
> consecutive content.
> +  @param[in]   AuthFlag         Authenticated variable flag.
> +
> +  @return  A UINT8* pointer to Variable Data.
> +
> +**/
> +UINT8 *
> +GetVariableDataPtr (
> +  IN  VARIABLE_HEADER  *Variable,
> +  IN  VARIABLE_HEADER  *VariableHeader,
> +  IN  BOOLEAN          AuthFlag
> +  );
> +
> +/**
> +  Get variable header that has consecutive content.
> +
> +  @param[in]  StoreInfo      Pointer to variable store info structure.
> +  @param[in]  Variable       Pointer to the Variable Header.
> +  @param[out] VariableHeader Pointer to Pointer to the Variable Header that
> has consecutive content.
> +
> +  @retval TRUE          Variable header is valid.
> +  @retval FALSE         Variable header is not valid.
> +
> +**/
> +BOOLEAN
> +GetVariableHeader (
> +  IN VARIABLE_STORE_INFO  *StoreInfo,
> +  IN VARIABLE_HEADER      *Variable,
> +  OUT VARIABLE_HEADER     **VariableHeader
> +  );
> +
> +/**
> +  This code gets the size of variable header.
> +
> +  @param[in] AuthFlag   Authenticated variable flag.
> +
> +  @return Size of variable header in bytes in type UINTN.
> +
> +**/
> +UINTN
> +GetVariableHeaderSize (
> +  IN  BOOLEAN  AuthFlag
> +  );
> +
> +/**
> +  Get variable name or data to output buffer.
> +
> +  @param[in]  StoreInfo     Pointer to variable store info structure.
> +  @param[in]  NameOrData    Pointer to the variable name/data that may be
> inconsecutive.
> +  @param[in]  Size          Variable name/data size.
> +  @param[out] Buffer        Pointer to output buffer to hold the variable
> name/data.
> +
> +**/
> +VOID
> +GetVariableNameOrData (
> +  IN VARIABLE_STORE_INFO  *StoreInfo,
> +  IN UINT8                *NameOrData,
> +  IN UINTN                Size,
> +  OUT UINT8               *Buffer
> +  );
> +
> +/**
> +  This function compares a variable with variable entries in database.
> +
> +  @param[in]  StoreInfo     Pointer to variable store info structure.
> +  @param[in]  Variable      Pointer to the variable in our database
> +  @param[in]  VariableHeader Pointer to the Variable Header that has
> consecutive content.
> +  @param[in]  VariableName  Name of the variable to compare to 'Variable'
> +  @param[in]  VendorGuid    GUID of the variable to compare to 'Variable'
> +  @param[out] PtrTrack      Variable Track Pointer structure that contains
> Variable Information.
> +
> +  @retval EFI_SUCCESS    Found match variable
> +  @retval EFI_NOT_FOUND  Variable not found
> +
> +**/
> +EFI_STATUS
> +CompareWithValidVariable (
> +  IN  VARIABLE_STORE_INFO     *StoreInfo,
> +  IN  VARIABLE_HEADER         *Variable,
> +  IN  VARIABLE_HEADER         *VariableHeader,
> +  IN  CONST CHAR16            *VariableName,
> +  IN  CONST EFI_GUID          *VendorGuid,
> +  OUT VARIABLE_POINTER_TRACK  *PtrTrack
> +  );
> +
> +/**
> +
> +  Retrieve details of the variable next to given variable within VariableStore.
> +
> +  If VarInfo->Address is NULL, the first one in VariableStore is returned.
> +
> +  VariableStart and/or VariableEnd can be given optionally for the situation
> +  in which the valid storage space is smaller than the VariableStore->Size.
> +  This usually happens when PEI variable services make a compact variable
> +  cache to save memory, which cannot make use VariableStore->Size to
> determine
> +  the correct variable storage range.
> +
> +  @param[in,out] VariableInfo             Pointer to variable information.
> +
> +  @retval EFI_INVALID_PARAMETER  VariableInfo or VariableStore is NULL.
> +  @retval EFI_NOT_FOUND          If the end of VariableStore is reached.
> +  @retval EFI_SUCCESS            The next variable is retrieved successfully.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +GetNextVariableInfo (
> +  IN  OUT PROTECTED_VARIABLE_INFO  *VariableInfo
> +  );
> +
> +/**
> +
> +  Retrieve details about a variable and return them in VariableInfo->Header.
> +
> +  If VariableInfo->Address is given, this function will calculate its offset
> +  relative to given variable storage via VariableStore; Otherwise, it will try
> +  other internal variable storages or cached copies. It's assumed that, for all
> +  copies of NV variable storage, all variables are stored in the same relative
> +  position. If VariableInfo->Address is found in the range of any storage copies,
> +  its offset relative to that storage should be the same in other copies.
> +
> +  If VariableInfo->Offset is given (non-zero) but not VariableInfo->Address,
> +  this function will return the variable memory address inside VariableStore,
> +  if given, via VariableInfo->Address; Otherwise, the address of other storage
> +  copies will be returned, if any.
> +
> +  For a new variable whose offset has not been determined, a value of -1 as
> +  VariableInfo->Offset should be passed to skip the offset calculation.
> +
> +  @param[in,out] VariableInfo             Pointer to variable information.
> +
> +  @retval EFI_INVALID_PARAMETER  VariableInfo is NULL or both VariableInfo-
> >Address
> +                                 and VariableInfo->Offset are NULL (0).
> +  @retval EFI_NOT_FOUND          If given Address or Offset is out of range of
> +                                 any given or internal storage copies.
> +  @retval EFI_SUCCESS            Variable details are retrieved successfully.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +GetVariableInfo (
> +  IN  OUT PROTECTED_VARIABLE_INFO  *VariableInfo
> +  );
> +
> +/**
> +
> +  Find variable specified with input parameters.
> +
> +  @param[in] StoreInfo             Pointer to variable information.
> +  @param[in] VariableName          Pointer to variable name.
> +  @param[in] VendorGuid            Pointer to variable GUID.
> +  @param[in] PtrTrack              Pointer to variable track.
> +
> +  @retval EFI_INVALID_PARAMETER  VariableInfo is NULL or both VariableInfo-
> >Address
> +                                 and VariableInfo->Offset are NULL (0).
> +  @retval EFI_NOT_FOUND          If given Address or Offset is out of range of
> +                                 any given or internal storage copies.
> +  @retval EFI_SUCCESS            Variable details are retrieved successfully.
> +
> +**/
> +EFI_STATUS
> +FindVariableEx (
> +  IN VARIABLE_STORE_INFO      *StoreInfo,
> +  IN CONST CHAR16             *VariableName,
> +  IN CONST EFI_GUID           *VendorGuid,
> +  OUT VARIABLE_POINTER_TRACK  *PtrTrack
> +  );
> +
> +#endif
> diff --git a/MdeModulePkg/Universal/Variable/Pei/VariableStore.h
> b/MdeModulePkg/Universal/Variable/Pei/VariableStore.h
> new file mode 100644
> index 000000000000..6e2f6f939bab
> --- /dev/null
> +++ b/MdeModulePkg/Universal/Variable/Pei/VariableStore.h
> @@ -0,0 +1,116 @@
> +/** @file
> +  Implement ReadOnly Variable Services required by PEIM and install
> +  PEI ReadOnly Varaiable2 PPI. These services operates the non volatile storage
> space.
> +
> +Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
> +SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#ifndef PEI_VARIABLE_STORE_H_
> +#define PEI_VARIABLE_STORE_H_
> +
> +/**
> +  Get variable store status.
> +
> +  @param[in]  VarStoreHeader  Pointer to the Variable Store Header.
> +
> +  @retval  EfiRaw      Variable store is raw
> +  @retval  EfiValid    Variable store is valid
> +  @retval  EfiInvalid  Variable store is invalid
> +
> +**/
> +VARIABLE_STORE_STATUS
> +GetVariableStoreStatus (
> +  IN VARIABLE_STORE_HEADER  *VarStoreHeader
> +  );
> +
> +/**
> +  Reports HOB variable store is available or not.
> +
> +  @retval EFI_NOT_READY  HOB variable store info not available.
> +  @retval EFI_NOT_FOUND  HOB variable store is NOT available.
> +  @retval EFI_SUCCESS    HOB variable store is available.
> +**/
> +EFI_STATUS
> +EFIAPI
> +IsHobVariableStoreAvailable (
> +  VOID
> +  );
> +
> +/**
> +  Get HOB variable store.
> +
> +  @param[out] StoreInfo             Return the store info.
> +
> +**/
> +VOID
> +GetHobVariableStore (
> +  OUT VARIABLE_STORE_INFO  *StoreInfo
> +  );
> +
> +/**
> +  Get NV variable store.
> +
> +  @param[out] StoreInfo             Return the store info.
> +  @param[out] VariableStoreHeader   Return header of FV containing the store.
> +
> +**/
> +VOID
> +GetNvVariableStore (
> +  OUT VARIABLE_STORE_INFO         *StoreInfo,
> +  OUT EFI_FIRMWARE_VOLUME_HEADER  **VariableFvHeader
> +  );
> +
> +/**
> +  Return the variable store header and the store info based on the Index.
> +
> +  @param[in]  Type       The type of the variable store.
> +  @param[out] StoreInfo  Return the store info.
> +
> +  @return  Pointer to the variable store header.
> +**/
> +VARIABLE_STORE_HEADER *
> +GetVariableStore (
> +  IN VARIABLE_STORE_TYPE   Type,
> +  OUT VARIABLE_STORE_INFO  *StoreInfo
> +  );
> +
> +/**
> +  Make a cached copy of NV variable storage.
> +
> +  To save memory in PEI phase, only valid variables are copied into cache.
> +  An IndexTable could be used to store the offset (relative to NV storage
> +  base) of each copied variable, in case we need to restore the storage
> +  as the same (valid) variables layout as in original one.
> +
> +  Variables with valid format and following state can be taken as valid:
> +    - with state VAR_ADDED;
> +    - with state VAR_IN_DELETED_TRANSITION but without the same variable
> +      with state VAR_ADDED;
> +    - with state VAR_ADDED and/or VAR_IN_DELETED_TRANSITION for variable
> +      MetaDataHmacVar.
> +
> +  @param[out]     StoreCacheBase    Base address of variable storage cache.
> +  @param[in,out]  StoreCacheSize    Size of space in StoreCacheBase.
> +  @param[out]     IndexTable        Buffer of index (offset) table with entries of
> +                                    VariableNumber.
> +  @param[out]     VariableNumber    Number of valid variables.
> +  @param[out]     AuthFlag          Aut-variable indicator.
> +
> +  @return EFI_INVALID_PARAMETER Invalid StoreCacheSize and/or
> StoreCacheBase.
> +  @return EFI_VOLUME_CORRUPTED  Invalid or no NV variable storage found.
> +  @return EFI_BUFFER_TOO_SMALL  StoreCacheSize is smaller than needed.
> +  @return EFI_SUCCESS           NV variable storage is cached successfully.
> +**/
> +EFI_STATUS
> +EFIAPI
> +InitNvVariableStore (
> +  OUT  EFI_PHYSICAL_ADDRESS  StoreCacheBase OPTIONAL,
> +  IN OUT  UINT32             *StoreCacheSize,
> +  OUT  UINT32                *IndexTable OPTIONAL,
> +  OUT  UINT32                *VariableNumber OPTIONAL,
> +  OUT  BOOLEAN               *AuthFlag OPTIONAL
> +  );
> +
> +#endif
> diff --git a/MdeModulePkg/Universal/Variable/Pei/Variable.c
> b/MdeModulePkg/Universal/Variable/Pei/Variable.c
> index b36dd0de67b2..ce790946626e 100644
> --- a/MdeModulePkg/Universal/Variable/Pei/Variable.c
> +++ b/MdeModulePkg/Universal/Variable/Pei/Variable.c
> @@ -2,20 +2,22 @@
>    Implement ReadOnly Variable Services required by PEIM and install
>    PEI ReadOnly Varaiable2 PPI. These services operates the non volatile storage
> space.
> 
> -Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
>  Copyright (c) Microsoft Corporation.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> 
>  #include "Variable.h"
> +#include "VariableParsing.h"
> +#include "VariableStore.h"
> 
>  //
>  // Module globals
>  //
>  EFI_PEI_READ_ONLY_VARIABLE2_PPI  mVariablePpi = {
> -  PeiGetVariable,
> -  PeiGetNextVariableName
> +  PeiGetVariableEx,
> +  PeiGetNextVariableNameEx
>  };
> 
>  EFI_PEI_PPI_DESCRIPTOR  mPpiListVariable = {
> @@ -41,759 +43,33 @@ PeimInitializeVariableServices (
>    IN CONST EFI_PEI_SERVICES     **PeiServices
>    )
>  {
> +  EFI_STATUS                     Status;
> +  PROTECTED_VARIABLE_CONTEXT_IN  ContextIn;
> +
> +  //
> +  // If protected variable services are not supported, EFI_UNSUPPORTED should
> +  // be always returned. Check it here.
> +  //
> +  ContextIn.StructVersion =
> PROTECTED_VARIABLE_CONTEXT_IN_STRUCT_VERSION;
> +  ContextIn.StructSize    = sizeof (ContextIn);
> +
> +  ContextIn.MaxVariableSize             = 0;
> +  ContextIn.VariableServiceUser         = FromPeiModule;
> +  ContextIn.GetVariableInfo             = GetVariableInfo;
> +  ContextIn.GetNextVariableInfo         = GetNextVariableInfo;
> +  ContextIn.FindVariableSmm             = NULL;
> +  ContextIn.UpdateVariableStore         = NULL;
> +  ContextIn.UpdateVariable              = NULL;
> +  ContextIn.IsHobVariableStoreAvailable = IsHobVariableStoreAvailable;
> +
> +  Status = ProtectedVariableLibInitialize (&ContextIn);
> +  if (EFI_ERROR (Status) && (Status != EFI_UNSUPPORTED)) {
> +    return Status;
> +  }
> +
>    return PeiServicesInstallPpi (&mPpiListVariable);
>  }
> 
> -/**
> -
> -  Gets the pointer to the first variable header in given variable store area.
> -
> -  @param VarStoreHeader  Pointer to the Variable Store Header.
> -
> -  @return Pointer to the first variable header.
> -
> -**/
> -VARIABLE_HEADER *
> -GetStartPointer (
> -  IN VARIABLE_STORE_HEADER  *VarStoreHeader
> -  )
> -{
> -  //
> -  // The start of variable store
> -  //
> -  return (VARIABLE_HEADER *)HEADER_ALIGN (VarStoreHeader + 1);
> -}
> -
> -/**
> -
> -  Gets the pointer to the end of the variable storage area.
> -
> -  This function gets pointer to the end of the variable storage
> -  area, according to the input variable store header.
> -
> -  @param VarStoreHeader  Pointer to the Variable Store Header.
> -
> -  @return Pointer to the end of the variable storage area.
> -
> -**/
> -VARIABLE_HEADER *
> -GetEndPointer (
> -  IN VARIABLE_STORE_HEADER  *VarStoreHeader
> -  )
> -{
> -  //
> -  // The end of variable store
> -  //
> -  return (VARIABLE_HEADER *)HEADER_ALIGN ((UINTN)VarStoreHeader +
> VarStoreHeader->Size);
> -}
> -
> -/**
> -  This code checks if variable header is valid or not.
> -
> -  @param  Variable  Pointer to the Variable Header.
> -
> -  @retval TRUE      Variable header is valid.
> -  @retval FALSE     Variable header is not valid.
> -
> -**/
> -BOOLEAN
> -IsValidVariableHeader (
> -  IN  VARIABLE_HEADER  *Variable
> -  )
> -{
> -  if ((Variable == NULL) || (Variable->StartId != VARIABLE_DATA)) {
> -    return FALSE;
> -  }
> -
> -  return TRUE;
> -}
> -
> -/**
> -  This code gets the size of variable header.
> -
> -  @param AuthFlag   Authenticated variable flag.
> -
> -  @return Size of variable header in bytes in type UINTN.
> -
> -**/
> -UINTN
> -GetVariableHeaderSize (
> -  IN  BOOLEAN  AuthFlag
> -  )
> -{
> -  UINTN  Value;
> -
> -  if (AuthFlag) {
> -    Value = sizeof (AUTHENTICATED_VARIABLE_HEADER);
> -  } else {
> -    Value = sizeof (VARIABLE_HEADER);
> -  }
> -
> -  return Value;
> -}
> -
> -/**
> -  This code gets the size of name of variable.
> -
> -  @param  Variable  Pointer to the Variable Header.
> -  @param  AuthFlag  Authenticated variable flag.
> -
> -  @return Size of variable in bytes in type UINTN.
> -
> -**/
> -UINTN
> -NameSizeOfVariable (
> -  IN  VARIABLE_HEADER  *Variable,
> -  IN  BOOLEAN          AuthFlag
> -  )
> -{
> -  AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
> -
> -  AuthVariable = (AUTHENTICATED_VARIABLE_HEADER *)Variable;
> -  if (AuthFlag) {
> -    if ((AuthVariable->State == (UINT8)(-1)) ||
> -        (AuthVariable->DataSize == (UINT32)(-1)) ||
> -        (AuthVariable->NameSize == (UINT32)(-1)) ||
> -        (AuthVariable->Attributes == (UINT32)(-1)))
> -    {
> -      return 0;
> -    }
> -
> -    return (UINTN)AuthVariable->NameSize;
> -  } else {
> -    if ((Variable->State == (UINT8)(-1)) ||
> -        (Variable->DataSize == (UINT32)(-1)) ||
> -        (Variable->NameSize == (UINT32)(-1)) ||
> -        (Variable->Attributes == (UINT32)(-1)))
> -    {
> -      return 0;
> -    }
> -
> -    return (UINTN)Variable->NameSize;
> -  }
> -}
> -
> -/**
> -  This code gets the size of data of variable.
> -
> -  @param  Variable  Pointer to the Variable Header.
> -  @param  AuthFlag  Authenticated variable flag.
> -
> -  @return Size of variable in bytes in type UINTN.
> -
> -**/
> -UINTN
> -DataSizeOfVariable (
> -  IN  VARIABLE_HEADER  *Variable,
> -  IN  BOOLEAN          AuthFlag
> -  )
> -{
> -  AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
> -
> -  AuthVariable = (AUTHENTICATED_VARIABLE_HEADER *)Variable;
> -  if (AuthFlag) {
> -    if ((AuthVariable->State == (UINT8)(-1)) ||
> -        (AuthVariable->DataSize == (UINT32)(-1)) ||
> -        (AuthVariable->NameSize == (UINT32)(-1)) ||
> -        (AuthVariable->Attributes == (UINT32)(-1)))
> -    {
> -      return 0;
> -    }
> -
> -    return (UINTN)AuthVariable->DataSize;
> -  } else {
> -    if ((Variable->State == (UINT8)(-1)) ||
> -        (Variable->DataSize == (UINT32)(-1)) ||
> -        (Variable->NameSize == (UINT32)(-1)) ||
> -        (Variable->Attributes == (UINT32)(-1)))
> -    {
> -      return 0;
> -    }
> -
> -    return (UINTN)Variable->DataSize;
> -  }
> -}
> -
> -/**
> -  This code gets the pointer to the variable name.
> -
> -  @param   Variable  Pointer to the Variable Header.
> -  @param   AuthFlag  Authenticated variable flag.
> -
> -  @return  A CHAR16* pointer to Variable Name.
> -
> -**/
> -CHAR16 *
> -GetVariableNamePtr (
> -  IN VARIABLE_HEADER  *Variable,
> -  IN BOOLEAN          AuthFlag
> -  )
> -{
> -  return (CHAR16 *)((UINTN)Variable + GetVariableHeaderSize (AuthFlag));
> -}
> -
> -/**
> -  This code gets the pointer to the variable guid.
> -
> -  @param Variable   Pointer to the Variable Header.
> -  @param AuthFlag   Authenticated variable flag.
> -
> -  @return A EFI_GUID* pointer to Vendor Guid.
> -
> -**/
> -EFI_GUID *
> -GetVendorGuidPtr (
> -  IN VARIABLE_HEADER  *Variable,
> -  IN BOOLEAN          AuthFlag
> -  )
> -{
> -  AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
> -
> -  AuthVariable = (AUTHENTICATED_VARIABLE_HEADER *)Variable;
> -  if (AuthFlag) {
> -    return &AuthVariable->VendorGuid;
> -  } else {
> -    return &Variable->VendorGuid;
> -  }
> -}
> -
> -/**
> -  This code gets the pointer to the variable data.
> -
> -  @param   Variable         Pointer to the Variable Header.
> -  @param   VariableHeader   Pointer to the Variable Header that has
> consecutive content.
> -  @param   AuthFlag         Authenticated variable flag.
> -
> -  @return  A UINT8* pointer to Variable Data.
> -
> -**/
> -UINT8 *
> -GetVariableDataPtr (
> -  IN  VARIABLE_HEADER  *Variable,
> -  IN  VARIABLE_HEADER  *VariableHeader,
> -  IN  BOOLEAN          AuthFlag
> -  )
> -{
> -  UINTN  Value;
> -
> -  //
> -  // Be careful about pad size for alignment
> -  //
> -  Value  =  (UINTN)GetVariableNamePtr (Variable, AuthFlag);
> -  Value += NameSizeOfVariable (VariableHeader, AuthFlag);
> -  Value += GET_PAD_SIZE (NameSizeOfVariable (VariableHeader, AuthFlag));
> -
> -  return (UINT8 *)Value;
> -}
> -
> -/**
> -  This code gets the pointer to the next variable header.
> -
> -  @param  StoreInfo         Pointer to variable store info structure.
> -  @param  Variable          Pointer to the Variable Header.
> -  @param  VariableHeader    Pointer to the Variable Header that has
> consecutive content.
> -
> -  @return  A VARIABLE_HEADER* pointer to next variable header.
> -
> -**/
> -VARIABLE_HEADER *
> -GetNextVariablePtr (
> -  IN  VARIABLE_STORE_INFO  *StoreInfo,
> -  IN  VARIABLE_HEADER      *Variable,
> -  IN  VARIABLE_HEADER      *VariableHeader
> -  )
> -{
> -  EFI_PHYSICAL_ADDRESS  TargetAddress;
> -  EFI_PHYSICAL_ADDRESS  SpareAddress;
> -  UINTN                 Value;
> -
> -  Value  =  (UINTN)GetVariableDataPtr (Variable, VariableHeader, StoreInfo-
> >AuthFlag);
> -  Value += DataSizeOfVariable (VariableHeader, StoreInfo->AuthFlag);
> -  Value += GET_PAD_SIZE (DataSizeOfVariable (VariableHeader, StoreInfo-
> >AuthFlag));
> -  //
> -  // Be careful about pad size for alignment
> -  //
> -  Value = HEADER_ALIGN (Value);
> -
> -  if (StoreInfo->FtwLastWriteData != NULL) {
> -    TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
> -    SpareAddress  = StoreInfo->FtwLastWriteData->SpareAddress;
> -    if (((UINTN)Variable < (UINTN)TargetAddress) && (Value >=
> (UINTN)TargetAddress)) {
> -      //
> -      // Next variable is in spare block.
> -      //
> -      Value = (UINTN)SpareAddress + (Value - (UINTN)TargetAddress);
> -    }
> -  }
> -
> -  return (VARIABLE_HEADER *)Value;
> -}
> -
> -/**
> -  Get variable store status.
> -
> -  @param  VarStoreHeader  Pointer to the Variable Store Header.
> -
> -  @retval  EfiRaw      Variable store is raw
> -  @retval  EfiValid    Variable store is valid
> -  @retval  EfiInvalid  Variable store is invalid
> -
> -**/
> -VARIABLE_STORE_STATUS
> -GetVariableStoreStatus (
> -  IN VARIABLE_STORE_HEADER  *VarStoreHeader
> -  )
> -{
> -  if ((CompareGuid (&VarStoreHeader->Signature,
> &gEfiAuthenticatedVariableGuid) ||
> -       CompareGuid (&VarStoreHeader->Signature, &gEfiVariableGuid)) &&
> -      (VarStoreHeader->Format == VARIABLE_STORE_FORMATTED) &&
> -      (VarStoreHeader->State == VARIABLE_STORE_HEALTHY)
> -      )
> -  {
> -    return EfiValid;
> -  }
> -
> -  if ((((UINT32 *)(&VarStoreHeader->Signature))[0] == 0xffffffff) &&
> -      (((UINT32 *)(&VarStoreHeader->Signature))[1] == 0xffffffff) &&
> -      (((UINT32 *)(&VarStoreHeader->Signature))[2] == 0xffffffff) &&
> -      (((UINT32 *)(&VarStoreHeader->Signature))[3] == 0xffffffff) &&
> -      (VarStoreHeader->Size == 0xffffffff) &&
> -      (VarStoreHeader->Format == 0xff) &&
> -      (VarStoreHeader->State == 0xff)
> -      )
> -  {
> -    return EfiRaw;
> -  } else {
> -    return EfiInvalid;
> -  }
> -}
> -
> -/**
> -  Compare two variable names, one of them may be inconsecutive.
> -
> -  @param StoreInfo      Pointer to variable store info structure.
> -  @param Name1          Pointer to one variable name.
> -  @param Name2          Pointer to another variable name.
> -  @param NameSize       Variable name size.
> -
> -  @retval TRUE          Name1 and Name2 are identical.
> -  @retval FALSE         Name1 and Name2 are not identical.
> -
> -**/
> -BOOLEAN
> -CompareVariableName (
> -  IN VARIABLE_STORE_INFO  *StoreInfo,
> -  IN CONST CHAR16         *Name1,
> -  IN CONST CHAR16         *Name2,
> -  IN UINTN                NameSize
> -  )
> -{
> -  EFI_PHYSICAL_ADDRESS  TargetAddress;
> -  EFI_PHYSICAL_ADDRESS  SpareAddress;
> -  UINTN                 PartialNameSize;
> -
> -  if (StoreInfo->FtwLastWriteData != NULL) {
> -    TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
> -    SpareAddress  = StoreInfo->FtwLastWriteData->SpareAddress;
> -    if (((UINTN)Name1 < (UINTN)TargetAddress) && (((UINTN)Name1 +
> NameSize) > (UINTN)TargetAddress)) {
> -      //
> -      // Name1 is inconsecutive.
> -      //
> -      PartialNameSize = (UINTN)TargetAddress - (UINTN)Name1;
> -      //
> -      // Partial content is in NV storage.
> -      //
> -      if (CompareMem ((UINT8 *)Name1, (UINT8 *)Name2, PartialNameSize) == 0)
> {
> -        //
> -        // Another partial content is in spare block.
> -        //
> -        if (CompareMem ((UINT8 *)(UINTN)SpareAddress, (UINT8 *)Name2 +
> PartialNameSize, NameSize - PartialNameSize) == 0) {
> -          return TRUE;
> -        }
> -      }
> -
> -      return FALSE;
> -    } else if (((UINTN)Name2 < (UINTN)TargetAddress) && (((UINTN)Name2 +
> NameSize) > (UINTN)TargetAddress)) {
> -      //
> -      // Name2 is inconsecutive.
> -      //
> -      PartialNameSize = (UINTN)TargetAddress - (UINTN)Name2;
> -      //
> -      // Partial content is in NV storage.
> -      //
> -      if (CompareMem ((UINT8 *)Name2, (UINT8 *)Name1, PartialNameSize) == 0)
> {
> -        //
> -        // Another partial content is in spare block.
> -        //
> -        if (CompareMem ((UINT8 *)(UINTN)SpareAddress, (UINT8 *)Name1 +
> PartialNameSize, NameSize - PartialNameSize) == 0) {
> -          return TRUE;
> -        }
> -      }
> -
> -      return FALSE;
> -    }
> -  }
> -
> -  //
> -  // Both Name1 and Name2 are consecutive.
> -  //
> -  if (CompareMem ((UINT8 *)Name1, (UINT8 *)Name2, NameSize) == 0) {
> -    return TRUE;
> -  }
> -
> -  return FALSE;
> -}
> -
> -/**
> -  This function compares a variable with variable entries in database.
> -
> -  @param  StoreInfo     Pointer to variable store info structure.
> -  @param  Variable      Pointer to the variable in our database
> -  @param  VariableHeader Pointer to the Variable Header that has consecutive
> content.
> -  @param  VariableName  Name of the variable to compare to 'Variable'
> -  @param  VendorGuid    GUID of the variable to compare to 'Variable'
> -  @param  PtrTrack      Variable Track Pointer structure that contains Variable
> Information.
> -
> -  @retval EFI_SUCCESS    Found match variable
> -  @retval EFI_NOT_FOUND  Variable not found
> -
> -**/
> -EFI_STATUS
> -CompareWithValidVariable (
> -  IN  VARIABLE_STORE_INFO     *StoreInfo,
> -  IN  VARIABLE_HEADER         *Variable,
> -  IN  VARIABLE_HEADER         *VariableHeader,
> -  IN  CONST CHAR16            *VariableName,
> -  IN  CONST EFI_GUID          *VendorGuid,
> -  OUT VARIABLE_POINTER_TRACK  *PtrTrack
> -  )
> -{
> -  VOID      *Point;
> -  EFI_GUID  *TempVendorGuid;
> -
> -  TempVendorGuid = GetVendorGuidPtr (VariableHeader, StoreInfo->AuthFlag);
> -
> -  if (VariableName[0] == 0) {
> -    PtrTrack->CurrPtr = Variable;
> -    return EFI_SUCCESS;
> -  } else {
> -    //
> -    // Don't use CompareGuid function here for performance reasons.
> -    // Instead we compare the GUID a UINT32 at a time and branch
> -    // on the first failed comparison.
> -    //
> -    if ((((INT32 *)VendorGuid)[0] == ((INT32 *)TempVendorGuid)[0]) &&
> -        (((INT32 *)VendorGuid)[1] == ((INT32 *)TempVendorGuid)[1]) &&
> -        (((INT32 *)VendorGuid)[2] == ((INT32 *)TempVendorGuid)[2]) &&
> -        (((INT32 *)VendorGuid)[3] == ((INT32 *)TempVendorGuid)[3])
> -        )
> -    {
> -      ASSERT (NameSizeOfVariable (VariableHeader, StoreInfo->AuthFlag) != 0);
> -      Point = (VOID *)GetVariableNamePtr (Variable, StoreInfo->AuthFlag);
> -      if (CompareVariableName (StoreInfo, VariableName, Point,
> NameSizeOfVariable (VariableHeader, StoreInfo->AuthFlag))) {
> -        PtrTrack->CurrPtr = Variable;
> -        return EFI_SUCCESS;
> -      }
> -    }
> -  }
> -
> -  return EFI_NOT_FOUND;
> -}
> -
> -/**
> -  Get HOB variable store.
> -
> -  @param[out] StoreInfo             Return the store info.
> -  @param[out] VariableStoreHeader   Return variable store header.
> -
> -**/
> -VOID
> -GetHobVariableStore (
> -  OUT VARIABLE_STORE_INFO    *StoreInfo,
> -  OUT VARIABLE_STORE_HEADER  **VariableStoreHeader
> -  )
> -{
> -  EFI_HOB_GUID_TYPE  *GuidHob;
> -
> -  //
> -  // Make sure there is no more than one Variable HOB.
> -  //
> -  DEBUG_CODE_BEGIN ();
> -  GuidHob = GetFirstGuidHob (&gEfiAuthenticatedVariableGuid);
> -  if (GuidHob != NULL) {
> -    if ((GetNextGuidHob (&gEfiAuthenticatedVariableGuid, GET_NEXT_HOB
> (GuidHob)) != NULL)) {
> -      DEBUG ((DEBUG_ERROR, "ERROR: Found two Auth Variable HOBs\n"));
> -      ASSERT (FALSE);
> -    } else if (GetFirstGuidHob (&gEfiVariableGuid) != NULL) {
> -      DEBUG ((DEBUG_ERROR, "ERROR: Found one Auth + one Normal Variable
> HOBs\n"));
> -      ASSERT (FALSE);
> -    }
> -  } else {
> -    GuidHob = GetFirstGuidHob (&gEfiVariableGuid);
> -    if (GuidHob != NULL) {
> -      if ((GetNextGuidHob (&gEfiVariableGuid, GET_NEXT_HOB (GuidHob)) !=
> NULL)) {
> -        DEBUG ((DEBUG_ERROR, "ERROR: Found two Normal Variable HOBs\n"));
> -        ASSERT (FALSE);
> -      }
> -    }
> -  }
> -
> -  DEBUG_CODE_END ();
> -
> -  GuidHob = GetFirstGuidHob (&gEfiAuthenticatedVariableGuid);
> -  if (GuidHob != NULL) {
> -    *VariableStoreHeader = (VARIABLE_STORE_HEADER
> *)GET_GUID_HOB_DATA (GuidHob);
> -    StoreInfo->AuthFlag  = TRUE;
> -  } else {
> -    GuidHob = GetFirstGuidHob (&gEfiVariableGuid);
> -    if (GuidHob != NULL) {
> -      *VariableStoreHeader = (VARIABLE_STORE_HEADER
> *)GET_GUID_HOB_DATA (GuidHob);
> -      StoreInfo->AuthFlag  = FALSE;
> -    }
> -  }
> -}
> -
> -/**
> -  Return the variable store header and the store info based on the Index.
> -
> -  @param Type       The type of the variable store.
> -  @param StoreInfo  Return the store info.
> -
> -  @return  Pointer to the variable store header.
> -**/
> -VARIABLE_STORE_HEADER *
> -GetVariableStore (
> -  IN VARIABLE_STORE_TYPE   Type,
> -  OUT VARIABLE_STORE_INFO  *StoreInfo
> -  )
> -{
> -  EFI_HOB_GUID_TYPE                     *GuidHob;
> -  EFI_FIRMWARE_VOLUME_HEADER            *FvHeader;
> -  VARIABLE_STORE_HEADER                 *VariableStoreHeader;
> -  EFI_PHYSICAL_ADDRESS                  NvStorageBase;
> -  UINT32                                NvStorageSize;
> -  FAULT_TOLERANT_WRITE_LAST_WRITE_DATA  *FtwLastWriteData;
> -  UINT32                                BackUpOffset;
> -
> -  StoreInfo->IndexTable       = NULL;
> -  StoreInfo->FtwLastWriteData = NULL;
> -  StoreInfo->AuthFlag         = FALSE;
> -  VariableStoreHeader         = NULL;
> -  switch (Type) {
> -    case VariableStoreTypeHob:
> -      GetHobVariableStore (StoreInfo, &VariableStoreHeader);
> -
> -      break;
> -
> -    case VariableStoreTypeNv:
> -      if (!PcdGetBool (PcdEmuVariableNvModeEnable)) {
> -        //
> -        // Emulated non-volatile variable mode is not enabled.
> -        //
> -
> -        NvStorageSize = PcdGet32 (PcdFlashNvStorageVariableSize);
> -        NvStorageBase = (EFI_PHYSICAL_ADDRESS)(PcdGet64
> (PcdFlashNvStorageVariableBase64) != 0 ?
> -                                               PcdGet64 (PcdFlashNvStorageVariableBase64) :
> -                                               PcdGet32 (PcdFlashNvStorageVariableBase)
> -                                               );
> -        ASSERT (NvStorageBase != 0);
> -
> -        //
> -        // First let FvHeader point to NV storage base.
> -        //
> -        FvHeader = (EFI_FIRMWARE_VOLUME_HEADER *)(UINTN)NvStorageBase;
> -
> -        //
> -        // Check the FTW last write data hob.
> -        //
> -        BackUpOffset = 0;
> -        GuidHob      = GetFirstGuidHob (&gEdkiiFaultTolerantWriteGuid);
> -        if (GuidHob != NULL) {
> -          FtwLastWriteData = (FAULT_TOLERANT_WRITE_LAST_WRITE_DATA
> *)GET_GUID_HOB_DATA (GuidHob);
> -          if (FtwLastWriteData->TargetAddress == NvStorageBase) {
> -            //
> -            // Let FvHeader point to spare block.
> -            //
> -            FvHeader = (EFI_FIRMWARE_VOLUME_HEADER
> *)(UINTN)FtwLastWriteData->SpareAddress;
> -            DEBUG ((DEBUG_INFO, "PeiVariable: NV storage is backed up in spare
> block: 0x%x\n", (UINTN)FtwLastWriteData->SpareAddress));
> -          } else if ((FtwLastWriteData->TargetAddress > NvStorageBase) &&
> (FtwLastWriteData->TargetAddress < (NvStorageBase + NvStorageSize))) {
> -            StoreInfo->FtwLastWriteData = FtwLastWriteData;
> -            //
> -            // Flash NV storage from the offset is backed up in spare block.
> -            //
> -            BackUpOffset = (UINT32)(FtwLastWriteData->TargetAddress -
> NvStorageBase);
> -            DEBUG ((DEBUG_INFO, "PeiVariable: High partial NV storage from
> offset: %x is backed up in spare block: 0x%x\n", BackUpOffset,
> (UINTN)FtwLastWriteData->SpareAddress));
> -            //
> -            // At least one block data in flash NV storage is still valid, so still leave
> FvHeader point to NV storage base.
> -            //
> -          }
> -        }
> -
> -        //
> -        // Check if the Firmware Volume is not corrupted
> -        //
> -        if ((FvHeader->Signature != EFI_FVH_SIGNATURE) || (!CompareGuid
> (&gEfiSystemNvDataFvGuid, &FvHeader->FileSystemGuid))) {
> -          DEBUG ((DEBUG_ERROR, "Firmware Volume for Variable Store is
> corrupted\n"));
> -          break;
> -        }
> -
> -        VariableStoreHeader = (VARIABLE_STORE_HEADER *)((UINT8 *)FvHeader +
> FvHeader->HeaderLength);
> -
> -        StoreInfo->AuthFlag = (BOOLEAN)(CompareGuid (&VariableStoreHeader-
> >Signature, &gEfiAuthenticatedVariableGuid));
> -
> -        GuidHob = GetFirstGuidHob (&gEfiVariableIndexTableGuid);
> -        if (GuidHob != NULL) {
> -          StoreInfo->IndexTable = GET_GUID_HOB_DATA (GuidHob);
> -        } else {
> -          //
> -          // If it's the first time to access variable region in flash, create a guid hob
> to record
> -          // VAR_ADDED type variable info.
> -          // Note that as the resource of PEI phase is limited, only store the limited
> number of
> -          // VAR_ADDED type variables to reduce access time.
> -          //
> -          StoreInfo->IndexTable              = (VARIABLE_INDEX_TABLE *)BuildGuidHob
> (&gEfiVariableIndexTableGuid, sizeof (VARIABLE_INDEX_TABLE));
> -          StoreInfo->IndexTable->Length      = 0;
> -          StoreInfo->IndexTable->StartPtr    = GetStartPointer
> (VariableStoreHeader);
> -          StoreInfo->IndexTable->EndPtr      = GetEndPointer (VariableStoreHeader);
> -          StoreInfo->IndexTable->GoneThrough = 0;
> -        }
> -      }
> -
> -      break;
> -
> -    default:
> -      ASSERT (FALSE);
> -      break;
> -  }
> -
> -  StoreInfo->VariableStoreHeader = VariableStoreHeader;
> -  return VariableStoreHeader;
> -}
> -
> -/**
> -  Get variable header that has consecutive content.
> -
> -  @param StoreInfo      Pointer to variable store info structure.
> -  @param Variable       Pointer to the Variable Header.
> -  @param VariableHeader Pointer to Pointer to the Variable Header that has
> consecutive content.
> -
> -  @retval TRUE          Variable header is valid.
> -  @retval FALSE         Variable header is not valid.
> -
> -**/
> -BOOLEAN
> -GetVariableHeader (
> -  IN VARIABLE_STORE_INFO  *StoreInfo,
> -  IN VARIABLE_HEADER      *Variable,
> -  OUT VARIABLE_HEADER     **VariableHeader
> -  )
> -{
> -  EFI_PHYSICAL_ADDRESS  TargetAddress;
> -  EFI_PHYSICAL_ADDRESS  SpareAddress;
> -  EFI_HOB_GUID_TYPE     *GuidHob;
> -  UINTN                 PartialHeaderSize;
> -
> -  if (Variable == NULL) {
> -    return FALSE;
> -  }
> -
> -  //
> -  // First assume variable header pointed by Variable is consecutive.
> -  //
> -  *VariableHeader = Variable;
> -
> -  if (StoreInfo->FtwLastWriteData != NULL) {
> -    TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
> -    SpareAddress  = StoreInfo->FtwLastWriteData->SpareAddress;
> -    if (((UINTN)Variable > (UINTN)SpareAddress) &&
> -        (((UINTN)Variable - (UINTN)SpareAddress + (UINTN)TargetAddress) >=
> (UINTN)GetEndPointer (StoreInfo->VariableStoreHeader)))
> -    {
> -      //
> -      // Reach the end of variable store.
> -      //
> -      return FALSE;
> -    }
> -
> -    if (((UINTN)Variable < (UINTN)TargetAddress) && (((UINTN)Variable +
> GetVariableHeaderSize (StoreInfo->AuthFlag)) > (UINTN)TargetAddress)) {
> -      //
> -      // Variable header pointed by Variable is inconsecutive,
> -      // create a guid hob to combine the two partial variable header content
> together.
> -      //
> -      GuidHob = GetFirstGuidHob (&gEfiCallerIdGuid);
> -      if (GuidHob != NULL) {
> -        *VariableHeader = (VARIABLE_HEADER *)GET_GUID_HOB_DATA (GuidHob);
> -      } else {
> -        *VariableHeader   = (VARIABLE_HEADER *)BuildGuidHob (&gEfiCallerIdGuid,
> GetVariableHeaderSize (StoreInfo->AuthFlag));
> -        PartialHeaderSize = (UINTN)TargetAddress - (UINTN)Variable;
> -        //
> -        // Partial content is in NV storage.
> -        //
> -        CopyMem ((UINT8 *)*VariableHeader, (UINT8 *)Variable,
> PartialHeaderSize);
> -        //
> -        // Another partial content is in spare block.
> -        //
> -        CopyMem ((UINT8 *)*VariableHeader + PartialHeaderSize, (UINT8
> *)(UINTN)SpareAddress, GetVariableHeaderSize (StoreInfo->AuthFlag) -
> PartialHeaderSize);
> -      }
> -    }
> -  } else {
> -    if (Variable >= GetEndPointer (StoreInfo->VariableStoreHeader)) {
> -      //
> -      // Reach the end of variable store.
> -      //
> -      return FALSE;
> -    }
> -  }
> -
> -  return IsValidVariableHeader (*VariableHeader);
> -}
> -
> -/**
> -  Get variable name or data to output buffer.
> -
> -  @param  StoreInfo     Pointer to variable store info structure.
> -  @param  NameOrData    Pointer to the variable name/data that may be
> inconsecutive.
> -  @param  Size          Variable name/data size.
> -  @param  Buffer        Pointer to output buffer to hold the variable name/data.
> -
> -**/
> -VOID
> -GetVariableNameOrData (
> -  IN VARIABLE_STORE_INFO  *StoreInfo,
> -  IN UINT8                *NameOrData,
> -  IN UINTN                Size,
> -  OUT UINT8               *Buffer
> -  )
> -{
> -  EFI_PHYSICAL_ADDRESS  TargetAddress;
> -  EFI_PHYSICAL_ADDRESS  SpareAddress;
> -  UINTN                 PartialSize;
> -
> -  if (StoreInfo->FtwLastWriteData != NULL) {
> -    TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
> -    SpareAddress  = StoreInfo->FtwLastWriteData->SpareAddress;
> -    if (((UINTN)NameOrData < (UINTN)TargetAddress) &&
> (((UINTN)NameOrData + Size) > (UINTN)TargetAddress)) {
> -      //
> -      // Variable name/data is inconsecutive.
> -      //
> -      PartialSize = (UINTN)TargetAddress - (UINTN)NameOrData;
> -      //
> -      // Partial content is in NV storage.
> -      //
> -      CopyMem (Buffer, NameOrData, PartialSize);
> -      //
> -      // Another partial content is in spare block.
> -      //
> -      CopyMem (Buffer + PartialSize, (UINT8 *)(UINTN)SpareAddress, Size -
> PartialSize);
> -      return;
> -    }
> -  }
> -
> -  //
> -  // Variable name/data is consecutive.
> -  //
> -  CopyMem (Buffer, NameOrData, Size);
> -}
> -
>  /**
>    Find the variable in the specified variable store.
> 
> @@ -1246,3 +522,107 @@ PeiGetNextVariableName (
>      }
>    }
>  }
> +
> +/**
> +  This service retrieves a variable's value using its name and GUID.
> +
> +  Read the specified variable from the UEFI variable store. If the Data
> +  buffer is too small to hold the contents of the variable, the error
> +  EFI_BUFFER_TOO_SMALL is returned and DataSize is set to the required buffer
> +  size to obtain the data.
> +
> +  @param  This                  A pointer to this instance of the
> EFI_PEI_READ_ONLY_VARIABLE2_PPI.
> +  @param  VariableName          A pointer to a null-terminated string that is the
> variable's name.
> +  @param  VariableGuid          A pointer to an EFI_GUID that is the variable's
> GUID. The combination of
> +                                VariableGuid and VariableName must be unique.
> +  @param  Attributes            If non-NULL, on return, points to the variable's
> attributes.
> +  @param  DataSize              On entry, points to the size in bytes of the Data
> buffer.
> +                                On return, points to the size of the data returned in Data.
> +  @param  Data                  Points to the buffer which will hold the returned
> variable value.
> +                                May be NULL with a zero DataSize in order to determine the
> size of the buffer needed.
> +
> +  @retval EFI_SUCCESS           The variable was read successfully.
> +  @retval EFI_NOT_FOUND         The variable was be found.
> +  @retval EFI_BUFFER_TOO_SMALL  The DataSize is too small for the resulting
> data.
> +                                DataSize is updated with the size required for
> +                                the specified variable.
> +  @retval EFI_INVALID_PARAMETER VariableName, VariableGuid, DataSize or
> Data is NULL.
> +  @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of
> a device error.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +PeiGetVariableEx (
> +  IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI  *This,
> +  IN CONST  CHAR16                           *VariableName,
> +  IN CONST  EFI_GUID                         *VariableGuid,
> +  OUT       UINT32                           *Attributes,
> +  IN OUT    UINTN                            *DataSize,
> +  OUT       VOID                             *Data OPTIONAL
> +  )
> +{
> +  EFI_STATUS  Status;
> +
> +  //
> +  // If variable protection is employed, always get variable data through
> +  // ProtectedVariableLib.
> +  //
> +  Status = ProtectedVariableLibGetByName (VariableName, VariableGuid,
> Attributes, DataSize, Data);
> +  if (Status != EFI_UNSUPPORTED) {
> +    return Status;
> +  }
> +
> +  return PeiGetVariable (This, VariableName, VariableGuid, Attributes, DataSize,
> Data);
> +}
> +
> +/**
> +  Return the next variable name and GUID.
> +
> +  This function is called multiple times to retrieve the VariableName
> +  and VariableGuid of all variables currently available in the system.
> +  On each call, the previous results are passed into the interface,
> +  and, on return, the interface returns the data for the next
> +  interface. When the entire variable list has been returned,
> +  EFI_NOT_FOUND is returned.
> +
> +  @param  This              A pointer to this instance of the
> EFI_PEI_READ_ONLY_VARIABLE2_PPI.
> +
> +  @param  VariableNameSize  On entry, points to the size of the buffer pointed
> to by VariableName.
> +                            On return, the size of the variable name buffer.
> +  @param  VariableName      On entry, a pointer to a null-terminated string that
> is the variable's name.
> +                            On return, points to the next variable's null-terminated name
> string.
> +  @param  VariableGuid      On entry, a pointer to an EFI_GUID that is the
> variable's GUID.
> +                            On return, a pointer to the next variable's GUID.
> +
> +  @retval EFI_SUCCESS           The variable was read successfully.
> +  @retval EFI_NOT_FOUND         The variable could not be found.
> +  @retval EFI_BUFFER_TOO_SMALL  The VariableNameSize is too small for the
> resulting
> +                                data. VariableNameSize is updated with the size
> +                                required for the specified variable.
> +  @retval EFI_INVALID_PARAMETER VariableName, VariableGuid or
> +                                VariableNameSize is NULL.
> +  @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of
> a device error.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +PeiGetNextVariableNameEx (
> +  IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI  *This,
> +  IN OUT UINTN                               *VariableNameSize,
> +  IN OUT CHAR16                              *VariableName,
> +  IN OUT EFI_GUID                            *VariableGuid
> +  )
> +{
> +  EFI_STATUS  Status;
> +
> +  //
> +  // If variable protection is employed, always get next variable through
> +  // ProtectedVariableLib.
> +  //
> +  Status = ProtectedVariableLibFindNext (VariableNameSize, VariableName,
> VariableGuid);
> +  if (Status != EFI_UNSUPPORTED) {
> +    return Status;
> +  }
> +
> +  return PeiGetNextVariableName (This, VariableNameSize, VariableName,
> VariableGuid);
> +}
> diff --git a/MdeModulePkg/Universal/Variable/Pei/VariableParsing.c
> b/MdeModulePkg/Universal/Variable/Pei/VariableParsing.c
> new file mode 100644
> index 000000000000..2d605d39cbb6
> --- /dev/null
> +++ b/MdeModulePkg/Universal/Variable/Pei/VariableParsing.c
> @@ -0,0 +1,941 @@
> +/** @file
> +  Implement ReadOnly Variable Services required by PEIM and install
> +  PEI ReadOnly Varaiable2 PPI. These services operates the non volatile storage
> space.
> +
> +Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
> +SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#include "Variable.h"
> +#include "VariableStore.h"
> +
> +/**
> +
> +  Gets the pointer to the first variable header in given variable store area.
> +
> +  @param[in] VarStoreHeader  Pointer to the Variable Store Header.
> +
> +  @return Pointer to the first variable header.
> +
> +**/
> +VARIABLE_HEADER *
> +GetStartPointer (
> +  IN VARIABLE_STORE_HEADER  *VarStoreHeader
> +  )
> +{
> +  //
> +  // The start of variable store
> +  //
> +  return (VARIABLE_HEADER *)HEADER_ALIGN (VarStoreHeader + 1);
> +}
> +
> +/**
> +
> +  Gets the pointer to the end of the variable storage area.
> +
> +  This function gets pointer to the end of the variable storage
> +  area, according to the input variable store header.
> +
> +  @param[in] VarStoreHeader  Pointer to the Variable Store Header.
> +
> +  @return Pointer to the end of the variable storage area.
> +
> +**/
> +VARIABLE_HEADER *
> +GetEndPointer (
> +  IN VARIABLE_STORE_HEADER  *VarStoreHeader
> +  )
> +{
> +  //
> +  // The end of variable store
> +  //
> +  return (VARIABLE_HEADER *)HEADER_ALIGN ((UINTN)VarStoreHeader +
> VarStoreHeader->Size);
> +}
> +
> +/**
> +  This code checks if variable header is valid or not.
> +
> +  @param[in]  Variable  Pointer to the Variable Header.
> +
> +  @retval TRUE      Variable header is valid.
> +  @retval FALSE     Variable header is not valid.
> +
> +**/
> +BOOLEAN
> +IsValidVariableHeader (
> +  IN  VARIABLE_HEADER  *Variable
> +  )
> +{
> +  if ((Variable == NULL) || (Variable->StartId != VARIABLE_DATA)) {
> +    return FALSE;
> +  }
> +
> +  return TRUE;
> +}
> +
> +/**
> +  This code gets the size of variable header.
> +
> +  @param[in] AuthFlag   Authenticated variable flag.
> +
> +  @return Size of variable header in bytes in type UINTN.
> +
> +**/
> +UINTN
> +GetVariableHeaderSize (
> +  IN  BOOLEAN  AuthFlag
> +  )
> +{
> +  UINTN  Value;
> +
> +  if (AuthFlag) {
> +    Value = sizeof (AUTHENTICATED_VARIABLE_HEADER);
> +  } else {
> +    Value = sizeof (VARIABLE_HEADER);
> +  }
> +
> +  return Value;
> +}
> +
> +/**
> +  This code gets the size of name of variable.
> +
> +  @param[in]  Variable  Pointer to the Variable Header.
> +  @param[in]  AuthFlag  Authenticated variable flag.
> +
> +  @return Size of variable in bytes in type UINTN.
> +
> +**/
> +UINTN
> +NameSizeOfVariable (
> +  IN  VARIABLE_HEADER  *Variable,
> +  IN  BOOLEAN          AuthFlag
> +  )
> +{
> +  AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
> +
> +  AuthVariable = (AUTHENTICATED_VARIABLE_HEADER *)Variable;
> +  if (AuthFlag) {
> +    if ((AuthVariable->State == (UINT8)(-1)) ||
> +        (AuthVariable->DataSize == (UINT32)(-1)) ||
> +        (AuthVariable->NameSize == (UINT32)(-1)) ||
> +        (AuthVariable->Attributes == (UINT32)(-1)))
> +    {
> +      return 0;
> +    }
> +
> +    return (UINTN)AuthVariable->NameSize;
> +  } else {
> +    if ((Variable->State == (UINT8)(-1)) ||
> +        (Variable->DataSize == (UINT32)(-1)) ||
> +        (Variable->NameSize == (UINT32)(-1)) ||
> +        (Variable->Attributes == (UINT32)(-1)))
> +    {
> +      return 0;
> +    }
> +
> +    return (UINTN)Variable->NameSize;
> +  }
> +}
> +
> +/**
> +  This code gets the size of data of variable.
> +
> +  @param[in]  Variable  Pointer to the Variable Header.
> +  @param[in]  AuthFlag  Authenticated variable flag.
> +
> +  @return Size of variable in bytes in type UINTN.
> +
> +**/
> +UINTN
> +DataSizeOfVariable (
> +  IN  VARIABLE_HEADER  *Variable,
> +  IN  BOOLEAN          AuthFlag
> +  )
> +{
> +  AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
> +
> +  AuthVariable = (AUTHENTICATED_VARIABLE_HEADER *)Variable;
> +  if (AuthFlag) {
> +    if ((AuthVariable->State == (UINT8)(-1)) ||
> +        (AuthVariable->DataSize == (UINT32)(-1)) ||
> +        (AuthVariable->NameSize == (UINT32)(-1)) ||
> +        (AuthVariable->Attributes == (UINT32)(-1)))
> +    {
> +      return 0;
> +    }
> +
> +    return (UINTN)AuthVariable->DataSize;
> +  } else {
> +    if ((Variable->State == (UINT8)(-1)) ||
> +        (Variable->DataSize == (UINT32)(-1)) ||
> +        (Variable->NameSize == (UINT32)(-1)) ||
> +        (Variable->Attributes == (UINT32)(-1)))
> +    {
> +      return 0;
> +    }
> +
> +    return (UINTN)Variable->DataSize;
> +  }
> +}
> +
> +/**
> +  This code gets the pointer to the variable name.
> +
> +  @param[in]   Variable  Pointer to the Variable Header.
> +  @param[in]   AuthFlag  Authenticated variable flag.
> +
> +  @return  A CHAR16* pointer to Variable Name.
> +
> +**/
> +CHAR16 *
> +GetVariableNamePtr (
> +  IN VARIABLE_HEADER  *Variable,
> +  IN BOOLEAN          AuthFlag
> +  )
> +{
> +  return (CHAR16 *)((UINTN)Variable + GetVariableHeaderSize (AuthFlag));
> +}
> +
> +/**
> +  This code gets the pointer to the variable guid.
> +
> +  @param[in] Variable   Pointer to the Variable Header.
> +  @param[in] AuthFlag   Authenticated variable flag.
> +
> +  @return A EFI_GUID* pointer to Vendor Guid.
> +
> +**/
> +EFI_GUID *
> +GetVendorGuidPtr (
> +  IN VARIABLE_HEADER  *Variable,
> +  IN BOOLEAN          AuthFlag
> +  )
> +{
> +  AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
> +
> +  AuthVariable = (AUTHENTICATED_VARIABLE_HEADER *)Variable;
> +  if (AuthFlag) {
> +    return &AuthVariable->VendorGuid;
> +  } else {
> +    return &Variable->VendorGuid;
> +  }
> +}
> +
> +/**
> +  This code gets the pointer to the variable data.
> +
> +  @param[in]   Variable         Pointer to the Variable Header.
> +  @param[in]   VariableHeader   Pointer to the Variable Header that has
> consecutive content.
> +  @param[in]   AuthFlag         Authenticated variable flag.
> +
> +  @return  A UINT8* pointer to Variable Data.
> +
> +**/
> +UINT8 *
> +GetVariableDataPtr (
> +  IN  VARIABLE_HEADER  *Variable,
> +  IN  VARIABLE_HEADER  *VariableHeader,
> +  IN  BOOLEAN          AuthFlag
> +  )
> +{
> +  UINTN  Value;
> +
> +  //
> +  // Be careful about pad size for alignment
> +  //
> +  Value  =  (UINTN)GetVariableNamePtr (Variable, AuthFlag);
> +  Value += NameSizeOfVariable (VariableHeader, AuthFlag);
> +  Value += GET_PAD_SIZE (NameSizeOfVariable (VariableHeader, AuthFlag));
> +
> +  return (UINT8 *)Value;
> +}
> +
> +/**
> +  This code gets the pointer to the next variable header.
> +
> +  @param[in]  StoreInfo         Pointer to variable store info structure.
> +  @param[in]  Variable          Pointer to the Variable Header.
> +  @param[in]  VariableHeader    Pointer to the Variable Header that has
> consecutive content.
> +
> +  @return  A VARIABLE_HEADER* pointer to next variable header.
> +
> +**/
> +VARIABLE_HEADER *
> +GetNextVariablePtr (
> +  IN  VARIABLE_STORE_INFO  *StoreInfo,
> +  IN  VARIABLE_HEADER      *Variable,
> +  IN  VARIABLE_HEADER      *VariableHeader
> +  )
> +{
> +  EFI_PHYSICAL_ADDRESS  TargetAddress;
> +  EFI_PHYSICAL_ADDRESS  SpareAddress;
> +  UINTN                 Value;
> +
> +  Value  =  (UINTN)GetVariableDataPtr (Variable, VariableHeader, StoreInfo-
> >AuthFlag);
> +  Value += DataSizeOfVariable (VariableHeader, StoreInfo->AuthFlag);
> +  Value += GET_PAD_SIZE (DataSizeOfVariable (VariableHeader, StoreInfo-
> >AuthFlag));
> +  //
> +  // Be careful about pad size for alignment
> +  //
> +  Value = HEADER_ALIGN (Value);
> +
> +  if (StoreInfo->FtwLastWriteData != NULL) {
> +    TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
> +    SpareAddress  = StoreInfo->FtwLastWriteData->SpareAddress;
> +    if (((UINTN)Variable < (UINTN)TargetAddress) && (Value >=
> (UINTN)TargetAddress)) {
> +      //
> +      // Next variable is in spare block.
> +      //
> +      Value = (UINTN)SpareAddress + (Value - (UINTN)TargetAddress);
> +    }
> +  }
> +
> +  return (VARIABLE_HEADER *)Value;
> +}
> +
> +/**
> +  Compare two variable names, one of them may be inconsecutive.
> +
> +  @param[in] StoreInfo      Pointer to variable store info structure.
> +  @param[in] Name1          Pointer to one variable name.
> +  @param[in] Name2          Pointer to another variable name.
> +  @param[in] NameSize       Variable name size.
> +
> +  @retval TRUE          Name1 and Name2 are identical.
> +  @retval FALSE         Name1 and Name2 are not identical.
> +
> +**/
> +BOOLEAN
> +CompareVariableName (
> +  IN VARIABLE_STORE_INFO  *StoreInfo,
> +  IN CONST CHAR16         *Name1,
> +  IN CONST CHAR16         *Name2,
> +  IN UINTN                NameSize
> +  )
> +{
> +  EFI_PHYSICAL_ADDRESS  TargetAddress;
> +  EFI_PHYSICAL_ADDRESS  SpareAddress;
> +  UINTN                 PartialNameSize;
> +
> +  if (StoreInfo->FtwLastWriteData != NULL) {
> +    TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
> +    SpareAddress  = StoreInfo->FtwLastWriteData->SpareAddress;
> +    if (((UINTN)Name1 < (UINTN)TargetAddress) && (((UINTN)Name1 +
> NameSize) > (UINTN)TargetAddress)) {
> +      //
> +      // Name1 is inconsecutive.
> +      //
> +      PartialNameSize = (UINTN)TargetAddress - (UINTN)Name1;
> +      //
> +      // Partial content is in NV storage.
> +      //
> +      if (CompareMem ((UINT8 *)Name1, (UINT8 *)Name2, PartialNameSize) ==
> 0) {
> +        //
> +        // Another partial content is in spare block.
> +        //
> +        if (CompareMem ((UINT8 *)(UINTN)SpareAddress, (UINT8 *)Name2 +
> PartialNameSize, NameSize - PartialNameSize) == 0) {
> +          return TRUE;
> +        }
> +      }
> +
> +      return FALSE;
> +    } else if (((UINTN)Name2 < (UINTN)TargetAddress) && (((UINTN)Name2 +
> NameSize) > (UINTN)TargetAddress)) {
> +      //
> +      // Name2 is inconsecutive.
> +      //
> +      PartialNameSize = (UINTN)TargetAddress - (UINTN)Name2;
> +      //
> +      // Partial content is in NV storage.
> +      //
> +      if (CompareMem ((UINT8 *)Name2, (UINT8 *)Name1, PartialNameSize) ==
> 0) {
> +        //
> +        // Another partial content is in spare block.
> +        //
> +        if (CompareMem ((UINT8 *)(UINTN)SpareAddress, (UINT8 *)Name1 +
> PartialNameSize, NameSize - PartialNameSize) == 0) {
> +          return TRUE;
> +        }
> +      }
> +
> +      return FALSE;
> +    }
> +  }
> +
> +  //
> +  // Both Name1 and Name2 are consecutive.
> +  //
> +  if (CompareMem ((UINT8 *)Name1, (UINT8 *)Name2, NameSize) == 0) {
> +    return TRUE;
> +  }
> +
> +  return FALSE;
> +}
> +
> +/**
> +  This function compares a variable with variable entries in database.
> +
> +  @param[in]   StoreInfo        Pointer to variable store info structure.
> +  @param[in]   Variable         Pointer to the variable in our database
> +  @param[in]   VariableHeader   Pointer to the Variable Header that has
> +                                consecutive content.
> +  @param[in]   VariableName     Name of the variable to compare to 'Variable'
> +  @param[in]   VendorGuid       GUID of the variable to compare to 'Variable'
> +  @param[out]  PtrTrack         Variable Track Pointer structure that contains
> +                                Variable Information.
> +
> +  @retval EFI_SUCCESS    Found match variable
> +  @retval EFI_NOT_FOUND  Variable not found
> +
> +**/
> +EFI_STATUS
> +CompareWithValidVariable (
> +  IN  VARIABLE_STORE_INFO     *StoreInfo,
> +  IN  VARIABLE_HEADER         *Variable,
> +  IN  VARIABLE_HEADER         *VariableHeader,
> +  IN  CONST CHAR16            *VariableName,
> +  IN  CONST EFI_GUID          *VendorGuid,
> +  OUT VARIABLE_POINTER_TRACK  *PtrTrack
> +  )
> +{
> +  VOID      *Point;
> +  EFI_GUID  *TempVendorGuid;
> +
> +  TempVendorGuid = GetVendorGuidPtr (VariableHeader, StoreInfo->AuthFlag);
> +
> +  if (VariableName[0] == 0) {
> +    PtrTrack->CurrPtr = Variable;
> +    return EFI_SUCCESS;
> +  } else {
> +    //
> +    // Don't use CompareGuid function here for performance reasons.
> +    // Instead we compare the GUID a UINT32 at a time and branch
> +    // on the first failed comparison.
> +    //
> +    if ((((INT32 *)VendorGuid)[0] == ((INT32 *)TempVendorGuid)[0]) &&
> +        (((INT32 *)VendorGuid)[1] == ((INT32 *)TempVendorGuid)[1]) &&
> +        (((INT32 *)VendorGuid)[2] == ((INT32 *)TempVendorGuid)[2]) &&
> +        (((INT32 *)VendorGuid)[3] == ((INT32 *)TempVendorGuid)[3])
> +        )
> +    {
> +      ASSERT (NameSizeOfVariable (VariableHeader, StoreInfo->AuthFlag) != 0);
> +      Point = (VOID *)GetVariableNamePtr (Variable, StoreInfo->AuthFlag);
> +      if (CompareVariableName (StoreInfo, VariableName, Point,
> NameSizeOfVariable (VariableHeader, StoreInfo->AuthFlag))) {
> +        PtrTrack->CurrPtr = Variable;
> +        return EFI_SUCCESS;
> +      }
> +    }
> +  }
> +
> +  return EFI_NOT_FOUND;
> +}
> +
> +/**
> +  Get variable header that has consecutive content.
> +
> +  @param[in]  StoreInfo       Pointer to variable store info structure.
> +  @param[in]  Variable        Pointer to the Variable Header.
> +  @param[out] VariableHeader  Pointer to Pointer to the Variable Header
> +                              that has consecutive content.
> +
> +  @retval TRUE          Variable header is valid.
> +  @retval FALSE         Variable header is not valid.
> +
> +**/
> +BOOLEAN
> +GetVariableHeader (
> +  IN VARIABLE_STORE_INFO  *StoreInfo,
> +  IN VARIABLE_HEADER      *Variable,
> +  OUT VARIABLE_HEADER     **VariableHeader
> +  )
> +{
> +  EFI_PHYSICAL_ADDRESS  TargetAddress;
> +  EFI_PHYSICAL_ADDRESS  SpareAddress;
> +  EFI_HOB_GUID_TYPE     *GuidHob;
> +  UINTN                 PartialHeaderSize;
> +
> +  if (Variable == NULL) {
> +    return FALSE;
> +  }
> +
> +  //
> +  // First assume variable header pointed by Variable is consecutive.
> +  //
> +  *VariableHeader = Variable;
> +
> +  if (StoreInfo->FtwLastWriteData != NULL) {
> +    TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
> +    SpareAddress  = StoreInfo->FtwLastWriteData->SpareAddress;
> +    if (((UINTN)Variable > (UINTN)SpareAddress) &&
> +        (((UINTN)Variable - (UINTN)SpareAddress + (UINTN)TargetAddress) >=
> (UINTN)GetEndPointer (StoreInfo->VariableStoreHeader)))
> +    {
> +      //
> +      // Reach the end of variable store.
> +      //
> +      return FALSE;
> +    }
> +
> +    if (((UINTN)Variable < (UINTN)TargetAddress) && (((UINTN)Variable +
> GetVariableHeaderSize (StoreInfo->AuthFlag)) > (UINTN)TargetAddress)) {
> +      //
> +      // Variable header pointed by Variable is inconsecutive,
> +      // create a guid hob to combine the two partial variable header content
> together.
> +      //
> +      GuidHob = GetFirstGuidHob (&gEfiCallerIdGuid);
> +      if (GuidHob != NULL) {
> +        *VariableHeader = (VARIABLE_HEADER *)GET_GUID_HOB_DATA
> (GuidHob);
> +      } else {
> +        *VariableHeader   = (VARIABLE_HEADER *)BuildGuidHob
> (&gEfiCallerIdGuid, GetVariableHeaderSize (StoreInfo->AuthFlag));
> +        PartialHeaderSize = (UINTN)TargetAddress - (UINTN)Variable;
> +        //
> +        // Partial content is in NV storage.
> +        //
> +        CopyMem ((UINT8 *)*VariableHeader, (UINT8 *)Variable,
> PartialHeaderSize);
> +        //
> +        // Another partial content is in spare block.
> +        //
> +        CopyMem ((UINT8 *)*VariableHeader + PartialHeaderSize, (UINT8
> *)(UINTN)SpareAddress, GetVariableHeaderSize (StoreInfo->AuthFlag) -
> PartialHeaderSize);
> +      }
> +    }
> +  } else {
> +    if (Variable >= GetEndPointer (StoreInfo->VariableStoreHeader)) {
> +      //
> +      // Reach the end of variable store.
> +      //
> +      return FALSE;
> +    }
> +  }
> +
> +  return IsValidVariableHeader (*VariableHeader);
> +}
> +
> +/**
> +  Get variable name or data to output buffer.
> +
> +  @param[in]   StoreInfo     Pointer to variable store info structure.
> +  @param[in]   NameOrData    Pointer to the variable name/data that may be
> inconsecutive.
> +  @param[in]   Size          Variable name/data size.
> +  @param[out]  Buffer        Pointer to output buffer to hold the variable
> name/data.
> +
> +**/
> +VOID
> +GetVariableNameOrData (
> +  IN VARIABLE_STORE_INFO  *StoreInfo,
> +  IN UINT8                *NameOrData,
> +  IN UINTN                Size,
> +  OUT UINT8               *Buffer
> +  )
> +{
> +  EFI_PHYSICAL_ADDRESS  TargetAddress;
> +  EFI_PHYSICAL_ADDRESS  SpareAddress;
> +  UINTN                 PartialSize;
> +
> +  if (StoreInfo->FtwLastWriteData != NULL) {
> +    TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
> +    SpareAddress  = StoreInfo->FtwLastWriteData->SpareAddress;
> +    if (((UINTN)NameOrData < (UINTN)TargetAddress) &&
> (((UINTN)NameOrData + Size) > (UINTN)TargetAddress)) {
> +      //
> +      // Variable name/data is inconsecutive.
> +      //
> +      PartialSize = (UINTN)TargetAddress - (UINTN)NameOrData;
> +      //
> +      // Partial content is in NV storage.
> +      //
> +      CopyMem (Buffer, NameOrData, PartialSize);
> +      //
> +      // Another partial content is in spare block.
> +      //
> +      CopyMem (Buffer + PartialSize, (UINT8 *)(UINTN)SpareAddress, Size -
> PartialSize);
> +      return;
> +    }
> +  }
> +
> +  //
> +  // Variable name/data is consecutive.
> +  //
> +  CopyMem (Buffer, NameOrData, Size);
> +}
> +
> +/**
> +
> +  Internal function to retrieve variable information.
> +
> +  @param[in,out] VariableInfo     Pointer to variable information.
> +  @param[in]     StoreInfo        Pointer to store copy of variable (optional).
> +  @param[in]     VariablePtr      Pointer to variable buffer.
> +  @param[in]     VariableHeader   Pointer to variable header.
> +
> +  @retval EFI_INVALID_PARAMETER  One ore more required parameters are
> NULL.
> +  @retval EFI_BUFFER_TOO_SMALL   Given buffer is too small to hold data.
> +  @retval EFI_SUCCESS            Variable details are retrieved successfully.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +GetVariableInfoInternal (
> +  IN  OUT PROTECTED_VARIABLE_INFO  *VariableInfo,
> +  IN      VARIABLE_STORE_INFO      *StoreInfo OPTIONAL,
> +  IN      VARIABLE_HEADER          *VariablePtr,
> +  IN      VARIABLE_HEADER          *VariableHeader
> +  )
> +{
> +  VARIABLE_HEADER                *VariableBuffer;
> +  AUTHENTICATED_VARIABLE_HEADER  *AuthVariableHeader;
> +  UINTN                          NameSize;
> +  UINTN                          DataSize;
> +  UINTN                          VariableSize;
> +
> +  if ((VariableInfo == NULL) || (VariablePtr == NULL) || (VariableHeader ==
> NULL)) {
> +    ASSERT (VariableInfo != NULL);
> +    ASSERT (VariablePtr != NULL);
> +    ASSERT (VariableHeader != NULL);
> +    return EFI_INVALID_PARAMETER;
> +  }
> +
> +  VariableBuffer = VariableInfo->Buffer;
> +
> +  //
> +  // Make a copy of the whole variable if VariableInfo->Buffer is given. But
> +  // don't do this if StoreInfo is not given, because VariableInfo->Buffer
> +  // has already hold a copy of variable in such situation.
> +  //
> +  NameSize = NameSizeOfVariable (VariableHeader, VariableInfo->Flags.Auth);
> +  DataSize = DataSizeOfVariable (VariableHeader, VariableInfo->Flags.Auth);
> +  if ((VariableBuffer != NULL) && (VariableBuffer != VariablePtr)) {
> +    if (StoreInfo != NULL) {
> +      CopyMem (
> +        VariableBuffer,
> +        VariableHeader,
> +        GetVariableHeaderSize (VariableInfo->Flags.Auth)
> +        );
> +      GetVariableNameOrData (
> +        StoreInfo,
> +        (UINT8 *)GetVariableNamePtr (VariablePtr, VariableInfo->Flags.Auth),
> +        NameSize,
> +        (UINT8 *)GetVariableNamePtr (VariableBuffer, VariableInfo->Flags.Auth)
> +        );
> +      GetVariableNameOrData (
> +        StoreInfo,
> +        (UINT8 *)GetVariableDataPtr (VariablePtr, VariableHeader, VariableInfo-
> >Flags.Auth),
> +        DataSize,
> +        (UINT8 *)GetVariableDataPtr (VariableBuffer, VariableHeader,
> VariableInfo->Flags.Auth)
> +        );
> +    } else {
> +      //
> +      // Suppose the variable is in consecutive space.
> +      //
> +      VariableSize = GetVariableHeaderSize (VariableInfo->Flags.Auth)
> +                     + NameSize + GET_PAD_SIZE (NameSize)
> +                     + DataSize;
> +      CopyMem (VariableBuffer, VariablePtr, VariableSize);
> +    }
> +  }
> +
> +  //
> +  // Generally, if no consecutive buffer passed in, don't return back any data.
> +  //
> +  // If follow pointers are NULL, return back pointers to following data inside
> +  // VariableInfo->Buffer, if it's given.
> +  //
> +  //  VariableInfo->Header.VariableName
> +  //  VariableInfo->Header.Data
> +  //  VariableInfo->Header.VendorGuid
> +  //  VariableInfo->Header.TimeStamp
> +  //
> +  // Otherwise, suppose they're buffers used to hold a copy of corresponding
> +  // data.
> +  //
> +  //
> +
> +  //
> +  // AuthVariable header
> +  //
> +  if (VariableInfo->Flags.Auth) {
> +    AuthVariableHeader = (AUTHENTICATED_VARIABLE_HEADER
> *)VariableHeader;
> +
> +    VariableInfo->Header.State          = AuthVariableHeader->State;
> +    VariableInfo->Header.Attributes     = AuthVariableHeader->Attributes;
> +    VariableInfo->Header.PubKeyIndex    = AuthVariableHeader->PubKeyIndex;
> +    VariableInfo->Header.MonotonicCount = ReadUnaligned64 (
> +                                            &(AuthVariableHeader->MonotonicCount)
> +                                            );
> +    if (VariableInfo->Header.TimeStamp != NULL) {
> +      CopyMem (
> +        VariableInfo->Header.TimeStamp,
> +        &AuthVariableHeader->TimeStamp,
> +        sizeof (EFI_TIME)
> +        );
> +    } else if (VariableBuffer != NULL) {
> +      AuthVariableHeader             = (AUTHENTICATED_VARIABLE_HEADER
> *)VariableBuffer;
> +      VariableInfo->Header.TimeStamp = &AuthVariableHeader->TimeStamp;
> +    }
> +  } else {
> +    VariableInfo->Header.State          = VariableHeader->State;
> +    VariableInfo->Header.Attributes     = VariableHeader->Attributes;
> +    VariableInfo->Header.PubKeyIndex    = 0;
> +    VariableInfo->Header.MonotonicCount = 0;
> +    VariableInfo->Header.TimeStamp      = NULL;
> +  }
> +
> +  //
> +  // VendorGuid
> +  //
> +  if (VariableInfo->Header.VendorGuid != NULL) {
> +    CopyGuid (
> +      VariableInfo->Header.VendorGuid,
> +      GetVendorGuidPtr (VariableHeader, VariableInfo->Flags.Auth)
> +      );
> +  } else if (VariableBuffer != NULL) {
> +    VariableInfo->Header.VendorGuid
> +      = GetVendorGuidPtr (VariableBuffer, VariableInfo->Flags.Auth);
> +  }
> +
> +  //
> +  // VariableName
> +  //
> +  if (  (VariableInfo->Header.VariableName != NULL)
> +     && (VariableInfo->Header.NameSize >= NameSize))
> +  {
> +    GetVariableNameOrData (
> +      StoreInfo,
> +      (UINT8 *)GetVariableNamePtr (VariablePtr, VariableInfo->Flags.Auth),
> +      NameSize,
> +      (UINT8 *)VariableInfo->Header.VariableName
> +      );
> +  } else if (VariableBuffer != NULL) {
> +    VariableInfo->Header.VariableName
> +      = GetVariableNamePtr (VariableBuffer, VariableInfo->Flags.Auth);
> +  } else if (VariableInfo->Header.VariableName != NULL) {
> +    return EFI_BUFFER_TOO_SMALL;
> +  }
> +
> +  //
> +  // Data
> +  //
> +  if (  (VariableInfo->Header.Data != NULL)
> +     && (VariableInfo->Header.DataSize >= DataSize))
> +  {
> +    GetVariableNameOrData (
> +      StoreInfo,
> +      GetVariableDataPtr (VariablePtr, VariableHeader, StoreInfo->AuthFlag),
> +      DataSize,
> +      VariableInfo->Header.Data
> +      );
> +  } else if (VariableBuffer != NULL) {
> +    VariableInfo->Header.Data
> +      = GetVariableDataPtr (VariableBuffer, VariableBuffer, VariableInfo-
> >Flags.Auth);
> +  } else if (VariableInfo->Header.Data != NULL) {
> +    return EFI_BUFFER_TOO_SMALL;
> +  }
> +
> +  //
> +  // Update size information about name & data.
> +  //
> +  VariableInfo->Header.NameSize = NameSize;
> +  VariableInfo->Header.DataSize = DataSize;
> +
> +  return EFI_SUCCESS;
> +}
> +
> +/**
> +
> +  Retrieve details about a variable, given by VariableInfo->Buffer or
> +  VariableInfo->Index, and pass the details back in VariableInfo->Header.
> +
> +  This function is used to resolve the variable data structure into
> +  VariableInfo->Header, for easier access later without revisiting the variable
> +  data in variable store. If pointers in the structure of VariableInfo->Header
> +  are not NULL, it's supposed that they are buffers passed in to hold a copy of
> +  data of corresponding data fields in variable data structure. Otherwise, this
> +  function simply returns pointers pointing to address of those data fields.
> +
> +  The variable is specified by either VariableInfo->Index or VariableInfo->Buffer.
> +  If VariableInfo->Index is given, this function finds the corresponding variable
> +  first from variable storage according to the Index.
> +
> +  If both VariableInfo->Index and VariableInfo->Buffer are given, it's supposed
> +  that VariableInfo->Buffer is a buffer passed in to hold a whole copy of
> +  requested variable data to be returned.
> +
> +  @param[in,out] VariableInfo             Pointer to variable information.
> +
> +  @retval EFI_INVALID_PARAMETER  VariableInfo is NULL or both VariableInfo-
> >Buffer
> +                                 and VariableInfo->Index are NULL (0).
> +  @retval EFI_NOT_FOUND          If given Buffer or Index is out of range of
> +                                 any given or internal storage copies.
> +  @retval EFI_SUCCESS            Variable details are retrieved successfully.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +GetVariableInfo (
> +  IN  OUT PROTECTED_VARIABLE_INFO  *VariableInfo
> +  )
> +{
> +  VARIABLE_HEADER      *VariablePtr;
> +  VARIABLE_HEADER      *VariableHeader;
> +  VARIABLE_STORE_TYPE  StoreType;
> +  VARIABLE_STORE_INFO  StoreInfo;
> +  UINTN                Offset;
> +
> +  if ((VariableInfo == NULL) ||
> +      ((VariableInfo->Buffer == NULL) && (VariableInfo->StoreIndex ==
> VAR_INDEX_INVALID)))
> +  {
> +    ASSERT (VariableInfo != NULL);
> +    ASSERT (VariableInfo->StoreIndex != VAR_INDEX_INVALID || VariableInfo-
> >Buffer != NULL);
> +    return EFI_INVALID_PARAMETER;
> +  }
> +
> +  StoreInfo.VariableStoreHeader = NULL;
> +  for (StoreType = VariableStoreTypeHob; StoreType < VariableStoreTypeMax;
> ++StoreType) {
> +    GetVariableStore (StoreType, &StoreInfo);
> +    if (StoreInfo.VariableStoreHeader != NULL) {
> +      break;
> +    }
> +  }
> +
> +  ASSERT (StoreInfo.VariableStoreHeader != NULL);
> +
> +  //
> +  // No StoreIndex? Don't retrieve variable information from store but just from
> +  // VariableInfo->Buffer.
> +  //
> +  if (VariableInfo->StoreIndex == VAR_INDEX_INVALID) {
> +    VariablePtr    = VariableInfo->Buffer;
> +    VariableHeader = VariablePtr;
> +
> +    return GetVariableInfoInternal (VariableInfo, NULL, VariablePtr,
> VariableHeader);
> +  }
> +
> +  Offset = (UINTN)VariableInfo->StoreIndex;
> +  if (  (StoreInfo.FtwLastWriteData != NULL)
> +     && (Offset >= ((UINTN)StoreInfo.FtwLastWriteData->TargetAddress
> +                    - (UINTN)StoreInfo.VariableStoreHeader)))
> +  {
> +    Offset -= ((UINTN)StoreInfo.FtwLastWriteData->TargetAddress
> +               - (UINTN)StoreInfo.VariableStoreHeader);
> +    VariablePtr = (VARIABLE_HEADER *)
> +                  ((UINTN)StoreInfo.FtwLastWriteData->SpareAddress + Offset);
> +  } else {
> +    VariablePtr = (VARIABLE_HEADER *)
> +                  ((UINTN)StoreInfo.VariableStoreHeader + Offset);
> +  }
> +
> +  //
> +  // Note that variable might be in unconsecutive space. Always get a copy
> +  // of its header in consecutive buffer.
> +  //
> +  if (!GetVariableHeader (&StoreInfo, VariablePtr, &VariableHeader)) {
> +    return EFI_NOT_FOUND;
> +  }
> +
> +  return GetVariableInfoInternal (VariableInfo, &StoreInfo, VariablePtr,
> VariableHeader);
> +}
> +
> +/**
> +
> +  Retrieve details of the variable next to given variable within VariableStore.
> +
> +  If VarInfo->Buffer is NULL, the first one in VariableStore is returned.
> +
> +  VariableStart and/or VariableEnd can be given optionally for the situation
> +  in which the valid storage space is smaller than the VariableStore->Size.
> +  This usually happens when PEI variable services make a compact variable
> +  cache to save memory, which cannot make use VariableStore->Size to
> determine
> +  the correct variable storage range.
> +
> +  @param[in,out] VariableInfo             Pointer to variable information.
> +
> +  @retval EFI_INVALID_PARAMETER  VariableInfo or VariableStore is NULL.
> +  @retval EFI_NOT_FOUND          If the end of VariableStore is reached.
> +  @retval EFI_SUCCESS            The next variable is retrieved successfully.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +GetNextVariableInfo (
> +  IN  OUT PROTECTED_VARIABLE_INFO  *VariableInfo
> +  )
> +{
> +  VARIABLE_HEADER      *VariablePtr;
> +  VARIABLE_HEADER      *VariableHeader;
> +  VARIABLE_STORE_INFO  StoreInfo;
> +  VARIABLE_STORE_TYPE  StoreType;
> +  UINTN                Offset;
> +
> +  if (VariableInfo == NULL) {
> +    ASSERT (VariableInfo != NULL);
> +    return EFI_INVALID_PARAMETER;
> +  }
> +
> +  StoreInfo.VariableStoreHeader = NULL;
> +  for (StoreType = VariableStoreTypeHob; StoreType < VariableStoreTypeMax;
> ++StoreType) {
> +    GetVariableStore (StoreType, &StoreInfo);
> +    if (StoreInfo.VariableStoreHeader != NULL) {
> +      break;
> +    }
> +  }
> +
> +  ASSERT (StoreInfo.VariableStoreHeader != NULL);
> +
> +  //
> +  // VariableInfo->StoreIndex is supposed to be the index to variable found
> +  // last time. Use it to get the variable next to it in store. If it's invalid,
> +  // return the first variable available in store.
> +  //
> +  VariableInfo->Flags.Auth = StoreInfo.AuthFlag;
> +  if (VariableInfo->StoreIndex == VAR_INDEX_INVALID) {
> +    VariablePtr = GetStartPointer (StoreInfo.VariableStoreHeader);
> +  } else {
> +    Offset = (UINTN)VariableInfo->StoreIndex;
> +    if (  (StoreInfo.FtwLastWriteData != NULL)
> +       && (Offset >= ((UINTN)StoreInfo.FtwLastWriteData->TargetAddress
> +                      - (UINTN)StoreInfo.VariableStoreHeader)))
> +    {
> +      Offset -= ((UINTN)StoreInfo.FtwLastWriteData->TargetAddress
> +                 - (UINTN)StoreInfo.VariableStoreHeader);
> +      VariablePtr = (VARIABLE_HEADER *)
> +                    ((UINTN)StoreInfo.FtwLastWriteData->SpareAddress + Offset);
> +    } else {
> +      VariablePtr = (VARIABLE_HEADER *)
> +                    ((UINTN)StoreInfo.VariableStoreHeader + Offset);
> +    }
> +
> +    //
> +    // Note that variable might be in unconsecutive space. Always get a copy
> +    // of its header in consecutive buffer.
> +    //
> +    if (!GetVariableHeader (&StoreInfo, VariablePtr, &VariableHeader)) {
> +      return EFI_NOT_FOUND;
> +    }
> +
> +    VariablePtr = GetNextVariablePtr (&StoreInfo, VariablePtr, VariableHeader);
> +  }
> +
> +  //
> +  // Get a copy of variable header in consecutive buffer.
> +  //
> +  if (!GetVariableHeader (&StoreInfo, VariablePtr, &VariableHeader)) {
> +    return EFI_NOT_FOUND;
> +  }
> +
> +  //
> +  // Use the offset to the start of variable store as index of the variable.
> +  //
> +  if (  (StoreInfo.FtwLastWriteData == NULL)
> +     || ((UINTN)VariablePtr < (UINTN)StoreInfo.FtwLastWriteData-
> >TargetAddress))
> +  {
> +    VariableInfo->StoreIndex
> +      = (UINT64)((UINTN)VariablePtr - (UINTN)StoreInfo.VariableStoreHeader);
> +  } else {
> +    VariableInfo->StoreIndex
> +      = (UINT64)((UINTN)StoreInfo.FtwLastWriteData->TargetAddress
> +                 - (UINTN)StoreInfo.VariableStoreHeader);
> +    VariableInfo->StoreIndex
> +      += (UINT64)((UINTN)VariablePtr - (UINTN)StoreInfo.FtwLastWriteData-
> >SpareAddress);
> +  }
> +
> +  if ((StoreType == VariableStoreTypeHob) && (VariableInfo->Buffer == NULL)) {
> +    VariableInfo->Buffer = VariablePtr;
> +  }
> +
> +  return GetVariableInfoInternal (VariableInfo, &StoreInfo, VariablePtr,
> VariableHeader);
> +}
> diff --git a/MdeModulePkg/Universal/Variable/Pei/VariableStore.c
> b/MdeModulePkg/Universal/Variable/Pei/VariableStore.c
> new file mode 100644
> index 000000000000..72bd17a43048
> --- /dev/null
> +++ b/MdeModulePkg/Universal/Variable/Pei/VariableStore.c
> @@ -0,0 +1,305 @@
> +/** @file
> +  Implement ReadOnly Variable Services required by PEIM and install
> +  PEI ReadOnly Varaiable2 PPI. These services operates the non volatile storage
> space.
> +
> +Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
> +SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#include "VariableParsing.h"
> +#include "VariableStore.h"
> +
> +/**
> +  Get variable store status.
> +
> +  @param[in]  VarStoreHeader  Pointer to the Variable Store Header.
> +
> +  @retval  EfiRaw      Variable store is raw
> +  @retval  EfiValid    Variable store is valid
> +  @retval  EfiInvalid  Variable store is invalid
> +
> +**/
> +VARIABLE_STORE_STATUS
> +GetVariableStoreStatus (
> +  IN VARIABLE_STORE_HEADER  *VarStoreHeader
> +  )
> +{
> +  if ((CompareGuid (&VarStoreHeader->Signature,
> &gEfiAuthenticatedVariableGuid) ||
> +       CompareGuid (&VarStoreHeader->Signature, &gEfiVariableGuid)) &&
> +      (VarStoreHeader->Format == VARIABLE_STORE_FORMATTED) &&
> +      (VarStoreHeader->State == VARIABLE_STORE_HEALTHY)
> +      )
> +  {
> +    return EfiValid;
> +  }
> +
> +  if ((((UINT32 *)(&VarStoreHeader->Signature))[0] == 0xffffffff) &&
> +      (((UINT32 *)(&VarStoreHeader->Signature))[1] == 0xffffffff) &&
> +      (((UINT32 *)(&VarStoreHeader->Signature))[2] == 0xffffffff) &&
> +      (((UINT32 *)(&VarStoreHeader->Signature))[3] == 0xffffffff) &&
> +      (VarStoreHeader->Size == 0xffffffff) &&
> +      (VarStoreHeader->Format == 0xff) &&
> +      (VarStoreHeader->State == 0xff)
> +      )
> +  {
> +    return EfiRaw;
> +  } else {
> +    return EfiInvalid;
> +  }
> +}
> +
> +/**
> +  Reports HOB variable store is available or not.
> +
> +  @retval EFI_NOT_READY  HOB variable store info not available.
> +  @retval EFI_NOT_FOUND  HOB variable store is NOT available.
> +  @retval EFI_SUCCESS    HOB variable store is available.
> +**/
> +EFI_STATUS
> +EFIAPI
> +IsHobVariableStoreAvailable (
> +  VOID
> +  )
> +{
> +  EFI_HOB_GUID_TYPE  *GuidHob;
> +  VOID               *VariableStoreInfoHob;
> +
> +  //
> +  // Discover if Variable Store Info Hob has been published by platform driver.
> +  // It contains information regards to HOB or NV Variable Store availability
> +  //
> +  GuidHob = GetFirstGuidHob (&gEfiPeiVariableStoreDiscoveredPpiGuid);
> +  if (GuidHob == NULL) {
> +    return EFI_NOT_READY;
> +  }
> +
> +  //
> +  // Check if HOB Variable Store is available
> +  //
> +  VariableStoreInfoHob = GET_GUID_HOB_DATA (GuidHob);
> +  if (*(BOOLEAN *)VariableStoreInfoHob == TRUE) {

[JianJW]
What's the scenario in which *(BOOLEAN *)VariableStoreInfoHob equals FALSE?
Which case the VariableStoreInfoHob is generated but HOB variable store available?
Is it possible to simply use VariableStoreDiscoveredPpi notify callback only? Then
you can just check HOB(gEfiAuthenticatedVariableGuid) or HOB(gEfiVariableGuid)
to confirm if the HOB version of variable store is available now.

> +    return EFI_SUCCESS;
> +  }
> +
> +  //
> +  // This might be NV Variable Store
> +  //
> +  return EFI_NOT_FOUND;
> +}
> +
> +/**
> +  Get HOB variable store.
> +
> +  @param[out] StoreInfo             Return the store info.
> +
> +**/
> +VOID
> +GetHobVariableStore (
> +  OUT VARIABLE_STORE_INFO  *StoreInfo
> +  )
> +{
> +  EFI_HOB_GUID_TYPE  *GuidHob;
> +
> +  //
> +  // Make sure there is no more than one Variable HOB.
> +  //
> +  DEBUG_CODE_BEGIN ();
> +  GuidHob = GetFirstGuidHob (&gEfiAuthenticatedVariableGuid);
> +  if (GuidHob != NULL) {
> +    if ((GetNextGuidHob (&gEfiAuthenticatedVariableGuid, GET_NEXT_HOB
> (GuidHob)) != NULL)) {
> +      DEBUG ((DEBUG_ERROR, "ERROR: Found two Auth Variable HOBs\n"));
> +      ASSERT (FALSE);
> +    } else if (GetFirstGuidHob (&gEfiVariableGuid) != NULL) {
> +      DEBUG ((DEBUG_ERROR, "ERROR: Found one Auth + one Normal Variable
> HOBs\n"));
> +      ASSERT (FALSE);
> +    }
> +  } else {
> +    GuidHob = GetFirstGuidHob (&gEfiVariableGuid);
> +    if (GuidHob != NULL) {
> +      if ((GetNextGuidHob (&gEfiVariableGuid, GET_NEXT_HOB (GuidHob)) !=
> NULL)) {
> +        DEBUG ((DEBUG_ERROR, "ERROR: Found two Normal Variable HOBs\n"));
> +        ASSERT (FALSE);
> +      }
> +    }
> +  }
> +
> +  DEBUG_CODE_END ();
> +
> +  GuidHob = GetFirstGuidHob (&gEfiAuthenticatedVariableGuid);
> +  if (GuidHob != NULL) {
> +    StoreInfo->VariableStoreHeader = (VARIABLE_STORE_HEADER
> *)GET_GUID_HOB_DATA (GuidHob);
> +    StoreInfo->AuthFlag            = TRUE;
> +  } else {
> +    GuidHob = GetFirstGuidHob (&gEfiVariableGuid);
> +    if (GuidHob != NULL) {
> +      StoreInfo->VariableStoreHeader = (VARIABLE_STORE_HEADER
> *)GET_GUID_HOB_DATA (GuidHob);
> +      StoreInfo->AuthFlag            = FALSE;
> +    }
> +  }
> +}
> +
> +/**
> +  Get NV variable store.
> +
> +  @param[out] StoreInfo             Return the store info.
> +  @param[out] VariableFvHeader      Return header of FV containing the store.
> +
> +**/
> +VOID
> +GetNvVariableStore (
> +  OUT VARIABLE_STORE_INFO         *StoreInfo,
> +  OUT EFI_FIRMWARE_VOLUME_HEADER  **VariableFvHeader
> +  )
> +{
> +  EFI_HOB_GUID_TYPE                     *GuidHob;
> +  EFI_FIRMWARE_VOLUME_HEADER            *FvHeader;
> +  VARIABLE_STORE_HEADER                 *StoreHeader;
> +  FAULT_TOLERANT_WRITE_LAST_WRITE_DATA  *HobData;
> +  FAULT_TOLERANT_WRITE_LAST_WRITE_DATA  *FtwLastWriteData;
> +  EFI_PHYSICAL_ADDRESS                  NvStorageBase;
> +  UINT32                                NvStorageSize;
> +  UINT32                                BackUpOffset;
> +
> +  NvStorageSize = PcdGet32 (PcdFlashNvStorageVariableSize);
> +  NvStorageBase = (EFI_PHYSICAL_ADDRESS)
> +                  (PcdGet64 (PcdFlashNvStorageVariableBase64) != 0)
> +                  ? PcdGet64 (PcdFlashNvStorageVariableBase64)
> +                  : PcdGet32 (PcdFlashNvStorageVariableBase);
> +  ASSERT (NvStorageBase != 0);
> +
> +  FvHeader = (EFI_FIRMWARE_VOLUME_HEADER *)(UINTN)NvStorageBase;
> +
> +  //
> +  // Check the FTW last write data hob.
> +  //
> +  BackUpOffset     = 0;
> +  FtwLastWriteData = NULL;
> +  HobData          = NULL;
> +  GuidHob          = GetFirstGuidHob (&gEdkiiFaultTolerantWriteGuid);
> +
> +  if (GuidHob != NULL) {
> +    HobData = (FAULT_TOLERANT_WRITE_LAST_WRITE_DATA
> *)GET_GUID_HOB_DATA (GuidHob);
> +    if (HobData->TargetAddress == NvStorageBase) {
> +      //
> +      // Let FvHeader point to spare block.
> +      //
> +      DEBUG ((
> +        EFI_D_INFO,
> +        "PeiVariable: NV storage is backed up in spare block: 0x%x\n",
> +        (UINTN)HobData->SpareAddress
> +        ));
> +
> +      FvHeader = (EFI_FIRMWARE_VOLUME_HEADER *)(UINTN)HobData-
> >SpareAddress;
> +      HobData  = NULL;
> +    } else if ((HobData->TargetAddress > NvStorageBase) &&
> +               (HobData->TargetAddress < (NvStorageBase + NvStorageSize)))
> +    {
> +      //
> +      // Flash NV storage from the offset is backed up in spare block.
> +      //
> +      BackUpOffset = (UINT32)(HobData->TargetAddress - NvStorageBase);
> +      DEBUG ((
> +        EFI_D_INFO,
> +        "PeiVariable: High partial NV storage from offset: %x is backed up in spare
> block: 0x%x\n",
> +        BackUpOffset,
> +        (UINTN)FtwLastWriteData->SpareAddress
> +        ));
> +      //
> +      // At least one block data in flash NV storage is still valid, so still
> +      // leave FvHeader point to NV storage base.
> +      //
> +    }
> +  }
> +
> +  if (StoreInfo != NULL) {
> +    StoreInfo->FtwLastWriteData = HobData;
> +  }
> +
> +  if (VariableFvHeader != NULL) {
> +    *VariableFvHeader = FvHeader;
> +  }
> +
> +  //
> +  // Check if the Firmware Volume is not corrupted
> +  //
> +  if ((FvHeader->Signature == EFI_FVH_SIGNATURE) &&
> +      CompareGuid (&gEfiSystemNvDataFvGuid, &FvHeader->FileSystemGuid))

[JianJW] It'd be better also validate the FvHeader->HeaderLength, to make sure
StoreHeader is in the valid area.

> +  {
> +    StoreHeader = (VARIABLE_STORE_HEADER *)((UINTN)FvHeader + FvHeader-
> >HeaderLength);
> +  } else {
> +    StoreHeader = NULL;
> +    DEBUG ((DEBUG_ERROR, "Firmware Volume for Variable Store is
> corrupted\n"));
> +  }
> +
> +  if (StoreInfo != NULL) {
> +    StoreInfo->VariableStoreHeader = StoreHeader;
> +    if (StoreHeader != NULL) {
> +      StoreInfo->AuthFlag = CompareGuid (
> +                              &StoreHeader->Signature,
> +                              &gEfiAuthenticatedVariableGuid
> +                              );
> +    }
> +  }
> +}
> +
> +/**
> +  Return the variable store header and the store info based on the Index.
> +
> +  @param[in]  Type       The type of the variable store.
> +  @param[out] StoreInfo  Return the store info.
> +
> +  @return  Pointer to the variable store header.
> +**/
> +VARIABLE_STORE_HEADER *
> +GetVariableStore (
> +  IN VARIABLE_STORE_TYPE   Type,
> +  OUT VARIABLE_STORE_INFO  *StoreInfo
> +  )
> +{
> +  EFI_HOB_GUID_TYPE  *GuidHob;
> +
> +  StoreInfo->VariableStoreHeader = NULL;
> +  StoreInfo->IndexTable          = NULL;
> +  StoreInfo->FtwLastWriteData    = NULL;
> +  StoreInfo->AuthFlag            = FALSE;
> +  switch (Type) {
> +    case VariableStoreTypeHob:
> +      GetHobVariableStore (StoreInfo);
> +      break;
> +
> +    case VariableStoreTypeNv:
> +      if (!PcdGetBool (PcdEmuVariableNvModeEnable)) {
> +        //
> +        // Emulated non-volatile variable mode is not enabled.
> +        //
> +        GetNvVariableStore (StoreInfo, NULL);
> +        if (StoreInfo->VariableStoreHeader != NULL) {
> +          GuidHob = GetFirstGuidHob (&gEfiVariableIndexTableGuid);
> +          if (GuidHob != NULL) {
> +            StoreInfo->IndexTable = GET_GUID_HOB_DATA (GuidHob);
> +          } else {
> +            //
> +            // If it's the first time to access variable region in flash, create a guid hob
> to record
> +            // VAR_ADDED type variable info.
> +            // Note that as the resource of PEI phase is limited, only store the
> limited number of
> +            // VAR_ADDED type variables to reduce access time.
> +            //
> +            StoreInfo->IndexTable              = (VARIABLE_INDEX_TABLE
> *)BuildGuidHob (&gEfiVariableIndexTableGuid, sizeof (VARIABLE_INDEX_TABLE));
> +            StoreInfo->IndexTable->Length      = 0;
> +            StoreInfo->IndexTable->StartPtr    = GetStartPointer (StoreInfo-
> >VariableStoreHeader);
> +            StoreInfo->IndexTable->EndPtr      = GetEndPointer (StoreInfo-
> >VariableStoreHeader);
> +            StoreInfo->IndexTable->GoneThrough = 0;
> +          }
> +        }
> +      }
> +
> +      break;
> +
> +    default:
> +      ASSERT (FALSE);
> +      break;
> +  }
> +
> +  return StoreInfo->VariableStoreHeader;
> +}
> --
> 2.35.1.windows.2


^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [Patch v2 09/28] MdeModulePkg: Add support for Protected Variables
  2022-04-29 18:04 ` [Patch v2 09/28] MdeModulePkg: Add support for Protected Variables Judah Vang
@ 2022-05-22 14:03   ` Wang, Jian J
  0 siblings, 0 replies; 49+ messages in thread
From: Wang, Jian J @ 2022-05-22 14:03 UTC (permalink / raw)
  To: Vang, Judah, devel@edk2.groups.io; +Cc: Gao, Liming, Mistry, Nishant C

Judah,

See my inline comments below.

Regards,
Jian

> -----Original Message-----
> From: Vang, Judah <judah.vang@intel.com>
> Sent: Saturday, April 30, 2022 2:04 AM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Gao, Liming
> <gaoliming@byosoft.com.cn>; Mistry, Nishant C <nishant.c.mistry@intel.com>
> Subject: [Patch v2 09/28] MdeModulePkg: Add support for Protected Variables
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594
> 
> Add support for Protected Variables.
> Add new API to retrieve Variable Infomation and data.
> Add new API to update variable in non-volatile storage or
> cached copy.
> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Liming Gao <gaoliming@byosoft.com.cn>
> Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Judah Vang <judah.vang@intel.com>
> ---
>  MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf    |    3
> +-
>  MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf           |    3 +-
>  MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.inf |
> 4 +-
>  MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf  |
> 3 +-
>  MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h                |  126 +-
>  MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.h         |   91 +-
>  MdeModulePkg/Universal/Variable/RuntimeDxe/Reclaim.c                 |  349 +++-
>  MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c                | 2139
> +++++++++++---------
>  MdeModulePkg/Universal/Variable/RuntimeDxe/VariableDxe.c             |   26 +-
>  MdeModulePkg/Universal/Variable/RuntimeDxe/VariableExLib.c           |  167 +-
>  MdeModulePkg/Universal/Variable/RuntimeDxe/VariableNonVolatile.c     |  194
> +-
>  MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.c         |  320
> ++-
>  MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeCache.c    |
> 2 +-
>  MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c             |   39 +-
>  MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.c   |
> 41 +-
>  15 files changed, 2454 insertions(+), 1053 deletions(-)
> 
> diff --git
> a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf
> index c9434df631ee..c0b90e6ca066 100644
> --- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf
> +++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf
> @@ -9,7 +9,7 @@
>  #  This external input must be validated carefully to avoid security issues such as
>  #  buffer overflow or integer overflow.
>  #
> -# Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
> +# Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
>  # Copyright (c) Microsoft Corporation.
>  # SPDX-License-Identifier: BSD-2-Clause-Patent
>  #
> @@ -73,6 +73,7 @@ [LibraryClasses]
>    VarCheckLib
>    VariablePolicyLib
>    VariablePolicyHelperLib
> +  ProtectedVariableLib
> 
>  [Protocols]
>    gEfiFirmwareVolumeBlockProtocolGuid           ## CONSUMES
> diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf
> index eaa97a01c6e5..6f9f027fbb0f 100644
> --- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf
> +++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf
> @@ -18,7 +18,7 @@
>  #  may not be modified without authorization. If platform fails to protect these
> resources,
>  #  the authentication service provided in this driver will be broken, and the
> behavior is undefined.
>  #
> -# Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>
> +# Copyright (c) 2010 - 2022, Intel Corporation. All rights reserved.<BR>
>  # Copyright (c) Microsoft Corporation.
>  # SPDX-License-Identifier: BSD-2-Clause-Patent
>  #
> @@ -82,6 +82,7 @@ [LibraryClasses]
>    UefiBootServicesTableLib
>    VariablePolicyLib
>    VariablePolicyHelperLib
> +  ProtectedVariableLib
> 
>  [Protocols]
>    gEfiSmmFirmwareVolumeBlockProtocolGuid        ## CONSUMES
> diff --git
> a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.inf
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.inf
> index a0d8b2267e92..5d2fc78ea917 100644
> ---
> a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.inf
> +++
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.inf
> @@ -13,7 +13,7 @@
>  #  may not be modified without authorization. If platform fails to protect these
> resources,
>  #  the authentication service provided in this driver will be broken, and the
> behavior is undefined.
>  #
> -# Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>
> +# Copyright (c) 2010 - 2022, Intel Corporation. All rights reserved.<BR>
>  # Copyright (c) Microsoft Corporation.<BR>
>  # SPDX-License-Identifier: BSD-2-Clause-Patent
>  #
> @@ -61,6 +61,8 @@ [LibraryClasses]
>    SafeIntLib
>    PcdLib
>    MmUnblockMemoryLib
> +  ProtectedVariableLib
> +  IoLib
[JianJW] 
Why's IoLib needed here? I didn't find any of its interfaces used in this patch.

> 
>  [Protocols]
>    gEfiVariableWriteArchProtocolGuid             ## PRODUCES
> diff --git
> a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf
> index d8c4f77e7f1f..6ea7b8d4293e 100644
> ---
> a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf
> +++
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf
> @@ -18,7 +18,7 @@
>  #  may not be modified without authorization. If platform fails to protect these
> resources,
>  #  the authentication service provided in this driver will be broken, and the
> behavior is undefined.
>  #
> -# Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>
> +# Copyright (c) 2010 - 2022, Intel Corporation. All rights reserved.<BR>
>  # Copyright (c) 2018, Linaro, Ltd. All rights reserved.<BR>
>  # Copyright (c) Microsoft Corporation.
>  # SPDX-License-Identifier: BSD-2-Clause-Patent
> @@ -78,6 +78,7 @@ [LibraryClasses]
>    VarCheckLib
>    VariablePolicyLib
>    VariablePolicyHelperLib
> +  ProtectedVariableLib
> 
>  [Protocols]
>    gEfiSmmFirmwareVolumeBlockProtocolGuid        ## CONSUMES
> diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h
> index 31e408976a35..97b4f9c906ff 100644
> --- a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h
> +++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h
> @@ -2,7 +2,7 @@
>    The internal header file includes the common header files, defines
>    internal structure and functions used by Variable modules.
> 
> -Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> @@ -31,6 +31,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
>  #include <Library/MemoryAllocationLib.h>
>  #include <Library/AuthVariableLib.h>
>  #include <Library/VarCheckLib.h>
> +#include <Library/ProtectedVariableLib.h>
>  #include <Guid/GlobalVariable.h>
>  #include <Guid/EventGroup.h>
>  #include <Guid/VariableFormat.h>
> @@ -823,4 +824,127 @@ VariableExLibAtRuntime (
>    VOID
>    );
> 
> +/**
> +  Is user variable?
> +
> +  @param[in] Variable   Pointer to variable header.
> +
> +  @retval TRUE          User variable.
> +  @retval FALSE         System variable.
> +
> +**/
> +BOOLEAN
> +IsUserVariable (
> +  IN VARIABLE_HEADER  *Variable
> +  );
> +
> +/**
> +
> +  Variable store garbage collection and reclaim operation.
> +
> +  @param[in]      VariableBase            Base address of variable store.
> +  @param[out]     LastVariableOffset      Offset of last variable.
> +  @param[in]      IsVolatile              The variable store is volatile or not;
> +                                          if it is non-volatile, need FTW.
> +  @param[in, out] UpdatingPtrTrack        Pointer to updating variable pointer
> track structure.
> +  @param[in]      NewVariable             Pointer to new variable.
> +  @param[in]      NewVariableSize         New variable size.
> +
> +  @return EFI_SUCCESS                  Reclaim operation has finished successfully.
> +  @return EFI_OUT_OF_RESOURCES         No enough memory resources or
> variable space.
> +  @return Others                       Unexpect error happened during reclaim
> operation.
> +
> +**/
> +EFI_STATUS
> +Reclaim (
> +  IN     EFI_PHYSICAL_ADDRESS    VariableBase,
> +  OUT    UINTN                   *LastVariableOffset,
> +  IN     BOOLEAN                 IsVolatile,
> +  IN OUT VARIABLE_POINTER_TRACK  *UpdatingPtrTrack,
> +  IN     VARIABLE_HEADER         *NewVariable,
> +  IN     UINTN                   NewVariableSize
> +  );
> +
> +/**
> +
> +  This function writes data to the FWH at the correct LBA even if the LBAs
> +  are fragmented.
> +
> +  @param Global                  Pointer to VARIABLE_GLOBAL structure.
> +  @param Volatile                Point out the Variable is Volatile or Non-Volatile.
> +  @param SetByIndex              TRUE if target pointer is given as index.
> +                                 FALSE if target pointer is absolute.
> +  @param Fvb                     Pointer to the writable FVB protocol.
> +  @param DataPtrIndex            Pointer to the Data from the end of
> VARIABLE_STORE_HEADER
> +                                 structure.
> +  @param DataSize                Size of data to be written.
> +  @param Buffer                  Pointer to the buffer from which data is written.
> +
> +  @retval EFI_INVALID_PARAMETER  Parameters not valid.
> +  @retval EFI_UNSUPPORTED        Fvb is a NULL for Non-Volatile variable
> update.
> +  @retval EFI_OUT_OF_RESOURCES   The remaining size is not enough.
> +  @retval EFI_SUCCESS            Variable store successfully updated.
> +
> +**/
> +EFI_STATUS
> +UpdateVariableStore (
> +  IN VARIABLE_GLOBAL                     *Global,
> +  IN BOOLEAN                             Volatile,
> +  IN BOOLEAN                             SetByIndex,
> +  IN EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *Fvb,
> +  IN UINTN                               DataPtrIndex,
> +  IN UINT32                              DataSize,
> +  IN UINT8                               *Buffer
> +  );
> +
> +/**
> +  Update partial data of a variable on NV storage and/or cached copy.
> +
> +  @param[in]  VariableInfo  Pointer to a variable with detailed information.
> +  @param[in]  Offset        Offset to write from.
> +  @param[in]  Size          Size of data Buffer to update.
> +  @param[in]  Buffer        Pointer to data buffer to update.
> +
> +  @retval EFI_SUCCESS             The variable data was updated successfully.
> +  @retval EFI_UNSUPPORTED         If this function is called directly in runtime.
> +  @retval EFI_INVALID_PARAMETER   If VariableInfo, Buffer or Size are not
> valid.
> +  @retval Others                  Failed to update NV storage or variable cache.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +VariableExLibUpdateNvVariable (
> +  IN  PROTECTED_VARIABLE_INFO  *VariableInfo,
> +  IN  UINTN                    Offset,
> +  IN  UINT32                   Size,
> +  IN  UINT8                    *Buffer
> +  );
> +
> +/**
> +  Finds the given variable in a variable store in SMM.
> +
> +  Caution: This function may receive untrusted input.
> +  The data size is external input, so this function will validate it carefully to
> avoid buffer overflow.
> +
> +  @param[in]      VariableName       Name of Variable to be found.
> +  @param[in]      VendorGuid         Variable vendor GUID.
> +  @param[out]     Attributes         Attribute value of the variable found.
> +  @param[in, out] DataSize           Size of Data found. If size is less than the
> +                                     data, this value contains the required size.
> +  @param[out]     Data               Data pointer.
> +
> +  @retval EFI_SUCCESS                Found the specified variable.
> +  @retval EFI_INVALID_PARAMETER      Invalid parameter.
> +  @retval EFI_NOT_FOUND              The specified variable could not be found.
> +
> +**/
> +EFI_STATUS
> +FindVariableInSmm (
> +  IN      CHAR16    *VariableName,
> +  IN      EFI_GUID  *VendorGuid,
> +  OUT     UINT32    *Attributes OPTIONAL,
> +  IN OUT  UINTN     *DataSize,
> +  OUT     VOID      *Data OPTIONAL
> +  );
> +
>  #endif
> diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.h
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.h
> index 951e8a089e34..3a4e8019aaf9 100644
> --- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.h
> +++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.h
> @@ -2,7 +2,7 @@
>    Functions in this module are associated with variable parsing operations and
>    are intended to be usable across variable driver source files.
> 
> -Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2019 - 2022, Intel Corporation. All rights reserved.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> @@ -19,6 +19,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>    @param[in] Variable           Pointer to the Variable Header.
>    @param[in] VariableStoreEnd   Pointer to the Variable Store End.
> +  @param[in] AuthFormat         Auth-variable indicator.
> 
>    @retval TRUE              Variable header is valid.
>    @retval FALSE             Variable header is not valid.
> @@ -27,7 +28,8 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
>  BOOLEAN
>  IsValidVariableHeader (
>    IN  VARIABLE_HEADER  *Variable,
> -  IN  VARIABLE_HEADER  *VariableStoreEnd
> +  IN  VARIABLE_HEADER  *VariableStoreEnd,
> +  IN  BOOLEAN          AuthFormat
>    );
> 
>  /**
> @@ -192,6 +194,28 @@ GetVariableDataOffset (
>    IN  BOOLEAN          AuthFormat
>    );
> 
> +/**
> +  Get variable data payload.
> +
> +  @param[in]      Variable     Pointer to the Variable Header.
> +  @param[out]     Data         Pointer to buffer used to store the variable data.
> +  @param[in]      DataSize     Size of buffer passed by Data.
> +  @param[out]     DataSize     Size of data copied into Data buffer.
> +  @param[in]      AuthFlag     Auth-variable indicator.
> +
> +  @return EFI_SUCCESS             Data was fetched.
> +  @return EFI_INVALID_PARAMETER   DataSize is NULL.
> +  @return EFI_BUFFER_TOO_SMALL    DataSize is smaller than size of variable
> data.
> +
> +**/
> +EFI_STATUS
> +GetVariableData (
> +  IN      VARIABLE_HEADER  *Variable,
> +  IN  OUT VOID             *Data,
> +  IN  OUT UINT32           *DataSize,
> +  IN      BOOLEAN          AuthFlag
> +  );
> +
>  /**
> 
>    This code gets the pointer to the next variable header.
> @@ -344,4 +368,67 @@ UpdateVariableInfo (
>    IN OUT VARIABLE_INFO_ENTRY  **VariableInfo
>    );
> 
> +/**
> +
> +  Retrieve details of the variable next to given variable within VariableStore.
> +
> +  If VarInfo->Address is NULL, the first one in VariableStore is returned.
> +
> +  VariableStart and/or VariableEnd can be given optionally for the situation
> +  in which the valid storage space is smaller than the VariableStore->Size.
> +  This usually happens when PEI variable services make a compact variable
> +  cache to save memory, which cannot make use VariableStore->Size to
> determine
> +  the correct variable storage range.
> +
> +  @param VariableStore            Pointer to a variable storage. It's optional.
> +  @param VariableStart            Start point of valid range in VariableStore.
> +  @param VariableEnd              End point of valid range in VariableStore.
> +  @param VariableInfo             Pointer to variable information.
[JianJW] 
The parameters don't  match the prototype below

> +
> +  @retval EFI_INVALID_PARAMETER  VariableInfo or VariableStore is NULL.
> +  @retval EFI_NOT_FOUND          If the end of VariableStore is reached.
> +  @retval EFI_SUCCESS            The next variable is retrieved successfully.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +GetNextVariableInfo (
> +  IN OUT  PROTECTED_VARIABLE_INFO  *VarInfo
> +  );
> +
> +/**
> +
> +  Retrieve details about a variable and return them in VariableInfo->Header.
> +
> +  If VariableInfo->Address is given, this function will calculate its offset
> +  relative to given variable storage via VariableStore; Otherwise, it will try
> +  other internal variable storages or cached copies. It's assumed that, for all
> +  copies of NV variable storage, all variables are stored in the same relative
> +  position. If VariableInfo->Address is found in the range of any storage copies,
> +  its offset relative to that storage should be the same in other copies.
> +
> +  If VariableInfo->Offset is given (non-zero) but not VariableInfo->Address,
> +  this function will return the variable memory address inside VariableStore,
> +  if given, via VariableInfo->Address; Otherwise, the address of other storage
> +  copies will be returned, if any.
> +
> +  For a new variable whose offset has not been determined, a value of -1 as
> +  VariableInfo->Offset should be passed to skip the offset calculation.
> +
> +  @param VariableStore            Pointer to a variable storage. It's optional.
> +  @param VariableInfo             Pointer to variable information.
[JianJW] 
The parameters doesn't match the prototype below

> +
> +  @retval EFI_INVALID_PARAMETER  VariableInfo is NULL or both VariableInfo-
> >Address
> +                                 and VariableInfo->Offset are NULL (0).
> +  @retval EFI_NOT_FOUND          If given Address or Offset is out of range of
> +                                 any given or internal storage copies.
> +  @retval EFI_SUCCESS            Variable details are retrieved successfully.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +GetVariableInfo (
> +  IN OUT  PROTECTED_VARIABLE_INFO  *VarInfo
> +  );
> +
>  #endif
> diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/Reclaim.c
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/Reclaim.c
> index fe64d0a2b3dd..a5b7f8a1fbe2 100644
> --- a/MdeModulePkg/Universal/Variable/RuntimeDxe/Reclaim.c
> +++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/Reclaim.c
> @@ -2,12 +2,15 @@
>    Handles non-volatile variable store garbage collection, using FTW
>    (Fault Tolerant Write) protocol.
> 
> -Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> 
>  #include "Variable.h"
> +#include "VariableNonVolatile.h"
> +#include "VariableParsing.h"
> +#include "VariableRuntimeCache.h"
> 
>  /**
>    Gets LBA of block and offset by given address.
> @@ -155,3 +158,347 @@ FtwVariableSpace (
> 
>    return Status;
>  }
> +
> +/**
> +
> +  Variable store garbage collection and reclaim operation.
> +
> +  @param[in]      VariableBase            Base address of variable store.
> +  @param[out]     LastVariableOffset      Offset of last variable.
> +  @param[in]      IsVolatile              The variable store is volatile or not;
> +                                          if it is non-volatile, need FTW.
> +  @param[in, out] UpdatingPtrTrack        Pointer to updating variable pointer
> track structure.
> +  @param[in]      NewVariable             Pointer to new variable.
> +  @param[in]      NewVariableSize         New variable size.
> +
> +  @return EFI_SUCCESS                  Reclaim operation has finished successfully.
> +  @return EFI_OUT_OF_RESOURCES         No enough memory resources or
> variable space.
> +  @return Others                       Unexpect error happened during reclaim
> operation.
> +
> +**/
> +EFI_STATUS
> +Reclaim (
> +  IN     EFI_PHYSICAL_ADDRESS    VariableBase,
> +  OUT    UINTN                   *LastVariableOffset,
> +  IN     BOOLEAN                 IsVolatile,
> +  IN OUT VARIABLE_POINTER_TRACK  *UpdatingPtrTrack,
> +  IN     VARIABLE_HEADER         *NewVariable,
> +  IN     UINTN                   NewVariableSize
> +  )
> +{
> +  VARIABLE_HEADER        *Variable;
> +  VARIABLE_HEADER        *AddedVariable;
> +  VARIABLE_HEADER        *NextVariable;
> +  VARIABLE_HEADER        *NextAddedVariable;
> +  VARIABLE_STORE_HEADER  *VariableStoreHeader;
> +  UINT8                  *ValidBuffer;
> +  UINTN                  MaximumBufferSize;
> +  UINTN                  VariableSize;
> +  UINTN                  NameSize;
> +  UINT8                  *CurrPtr;
> +  VOID                   *Point0;
> +  VOID                   *Point1;
> +  BOOLEAN                FoundAdded;
> +  EFI_STATUS             Status;
> +  EFI_STATUS             DoneStatus;
> +  UINTN                  CommonVariableTotalSize;
> +  UINTN                  CommonUserVariableTotalSize;
> +  UINTN                  HwErrVariableTotalSize;
> +  VARIABLE_HEADER        *UpdatingVariable;
> +  VARIABLE_HEADER        *UpdatingInDeletedTransition;
> +  BOOLEAN                AuthFormat;
> +
> +  AuthFormat                  = mVariableModuleGlobal->VariableGlobal.AuthFormat;
> +  UpdatingVariable            = NULL;
> +  UpdatingInDeletedTransition = NULL;
> +  if (UpdatingPtrTrack != NULL) {
> +    UpdatingVariable            = UpdatingPtrTrack->CurrPtr;
> +    UpdatingInDeletedTransition = UpdatingPtrTrack->InDeletedTransitionPtr;
> +  }
> +
> +  VariableStoreHeader = (VARIABLE_STORE_HEADER *)((UINTN)VariableBase);
> +
> +  CommonVariableTotalSize     = 0;
> +  CommonUserVariableTotalSize = 0;
> +  HwErrVariableTotalSize      = 0;
> +
> +  if (IsVolatile || mVariableModuleGlobal->VariableGlobal.EmuNvMode) {
> +    //
> +    // Start Pointers for the variable.
> +    //
> +    Variable          = GetStartPointer (VariableStoreHeader);
> +    MaximumBufferSize = sizeof (VARIABLE_STORE_HEADER);
> +
> +    while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader),
> AuthFormat)) {
> +      NextVariable = GetNextVariablePtr (Variable, AuthFormat);
> +      if (((Variable->State == VAR_ADDED) || (Variable->State ==
> (VAR_IN_DELETED_TRANSITION & VAR_ADDED))) &&
> +          (Variable != UpdatingVariable) &&
> +          (Variable != UpdatingInDeletedTransition)
> +          )
> +      {
> +        VariableSize       = (UINTN)NextVariable - (UINTN)Variable;
> +        MaximumBufferSize += VariableSize;
> +      }
> +
> +      Variable = NextVariable;
> +    }
> +
> +    if (NewVariable != NULL) {
> +      //
> +      // Add the new variable size.
> +      //
> +      MaximumBufferSize += NewVariableSize;
> +    }
> +
> +    //
> +    // Reserve the 1 Bytes with Oxff to identify the
> +    // end of the variable buffer.
> +    //
> +    MaximumBufferSize += 1;
> +    ValidBuffer        = AllocatePool (MaximumBufferSize);
> +    if (ValidBuffer == NULL) {
> +      return EFI_OUT_OF_RESOURCES;
> +    }
> +  } else {
> +    //
> +    // For NV variable reclaim, don't allocate pool here and just use
> mNvVariableCache
> +    // as the buffer to reduce SMRAM consumption for SMM variable driver.
> +    //
> +    MaximumBufferSize = mNvVariableCache->Size;
> +    ValidBuffer       = (UINT8 *)mNvVariableCache;
> +  }
> +
> +  SetMem (ValidBuffer, MaximumBufferSize, 0xff);
> +
> +  //
> +  // Copy variable store header.
> +  //
> +  CopyMem (ValidBuffer, VariableStoreHeader, sizeof
> (VARIABLE_STORE_HEADER));
> +  CurrPtr = (UINT8 *)GetStartPointer ((VARIABLE_STORE_HEADER *)ValidBuffer);
> +
> +  //
> +  // Reinstall all ADDED variables as long as they are not identical to Updating
> Variable.
> +  //
> +  Variable = GetStartPointer (VariableStoreHeader);
> +  while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader),
> AuthFormat)) {
> +    NextVariable = GetNextVariablePtr (Variable, AuthFormat);
> +    if ((Variable != UpdatingVariable) && (Variable->State == VAR_ADDED)) {
> +      VariableSize = (UINTN)NextVariable - (UINTN)Variable;
> +      CopyMem (CurrPtr, (UINT8 *)Variable, VariableSize);
> +      if (!IsVolatile) {
> +        (VOID)ProtectedVariableLibRefresh (
> +                (VARIABLE_HEADER *)CurrPtr,
> +                VariableSize,
> +                (UINTN)CurrPtr - (UINTN)ValidBuffer,
> +                FALSE
> +                );
> +
> +        if ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD)
> +            == EFI_VARIABLE_HARDWARE_ERROR_RECORD)
> +        {
> +          HwErrVariableTotalSize += VariableSize;
> +        } else {
> +          CommonVariableTotalSize += VariableSize;
> +          if (IsUserVariable (Variable)) {
> +            CommonUserVariableTotalSize += VariableSize;
> +          }
> +        }
> +      }
> +
> +      CurrPtr += VariableSize;
> +    }
> +
> +    Variable = NextVariable;
> +  }
> +
> +  //
> +  // Reinstall all in delete transition variables.
> +  //
> +  Variable = GetStartPointer (VariableStoreHeader);
> +  while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader),
> AuthFormat)) {
> +    NextVariable = GetNextVariablePtr (Variable, AuthFormat);
> +    if ((Variable != UpdatingVariable) && (Variable !=
> UpdatingInDeletedTransition) && (Variable->State ==
> (VAR_IN_DELETED_TRANSITION & VAR_ADDED)) &&
> +        (ProtectedVariableLibIsHmac (GetVariableNamePtr (Variable, AuthFormat))
> == FALSE))
> +    {
> +      FoundAdded    = FALSE;
> +      AddedVariable = GetStartPointer ((VARIABLE_STORE_HEADER *)ValidBuffer);
> +      while (IsValidVariableHeader (AddedVariable, GetEndPointer
> ((VARIABLE_STORE_HEADER *)ValidBuffer), AuthFormat)) {
> +        NextAddedVariable = GetNextVariablePtr (AddedVariable, AuthFormat);
> +        NameSize          = NameSizeOfVariable (AddedVariable, AuthFormat);
> +        if (CompareGuid (
> +              GetVendorGuidPtr (AddedVariable, AuthFormat),
> +              GetVendorGuidPtr (Variable, AuthFormat)
> +              ) && (NameSize == NameSizeOfVariable (Variable, AuthFormat)))
> +        {
> +          Point0 = (VOID *)GetVariableNamePtr (AddedVariable, AuthFormat);
> +          Point1 = (VOID *)GetVariableNamePtr (Variable, AuthFormat);
> +          if (CompareMem (Point0, Point1, NameSize) == 0) {
> +            FoundAdded = TRUE;
> +            break;
> +          }
> +        }
> +
> +        AddedVariable = NextAddedVariable;
> +      }
> +
> +      if (!FoundAdded) {
> +        //
> +        // Promote VAR_IN_DELETED_TRANSITION to VAR_ADDED.
> +        //
> +        VariableSize = (UINTN)NextVariable - (UINTN)Variable;
> +        CopyMem (CurrPtr, (UINT8 *)Variable, VariableSize);
> +        ((VARIABLE_HEADER *)CurrPtr)->State = VAR_ADDED;
> +        if (!IsVolatile) {
> +          (VOID)ProtectedVariableLibRefresh (
> +                  (VARIABLE_HEADER *)CurrPtr,
> +                  VariableSize,
> +                  (UINTN)CurrPtr - (UINTN)ValidBuffer,
> +                  FALSE
> +                  );
> +
> +          if ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD)
> +              == EFI_VARIABLE_HARDWARE_ERROR_RECORD)
> +          {
> +            HwErrVariableTotalSize += VariableSize;
> +          } else {
> +            CommonVariableTotalSize += VariableSize;
> +            if (IsUserVariable (Variable)) {
> +              CommonUserVariableTotalSize += VariableSize;
> +            }
> +          }
> +        }
> +
> +        CurrPtr += VariableSize;
> +      }
> +    }
> +
> +    Variable = NextVariable;
> +  }
> +
> +  //
> +  // Install the new variable if it is not NULL.
> +  //
> +  if (NewVariable != NULL) {
> +    if (((UINTN)CurrPtr - (UINTN)ValidBuffer) + NewVariableSize >
> VariableStoreHeader->Size) {
> +      //
> +      // No enough space to store the new variable.
> +      //
> +      Status = EFI_OUT_OF_RESOURCES;
> +      goto Done;
> +    }
> +
> +    if (!IsVolatile) {
> +      if ((NewVariable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD)
> == EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
> +        HwErrVariableTotalSize += NewVariableSize;
> +      } else if ((NewVariable->Attributes &
> EFI_VARIABLE_HARDWARE_ERROR_RECORD) !=
> EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
> +        CommonVariableTotalSize += NewVariableSize;
> +        if (IsUserVariable (NewVariable)) {
> +          CommonUserVariableTotalSize += NewVariableSize;
> +        }
> +      }
> +
> +      if ((HwErrVariableTotalSize > PcdGet32 (PcdHwErrStorageSize)) ||
> +          (CommonVariableTotalSize > mVariableModuleGlobal-
> >CommonVariableSpace) ||
> +          (CommonUserVariableTotalSize > mVariableModuleGlobal-
> >CommonMaxUserVariableSpace))
> +      {
> +        //
> +        // No enough space to store the new variable by NV or NV+HR attribute.
> +        //
> +        Status = EFI_OUT_OF_RESOURCES;
> +        goto Done;
> +      }
> +    }
> +
> +    CopyMem (CurrPtr, (UINT8 *)NewVariable, NewVariableSize);
> +    ((VARIABLE_HEADER *)CurrPtr)->State = VAR_ADDED;
> +    if (UpdatingVariable != NULL) {
> +      UpdatingPtrTrack->CurrPtr                = (VARIABLE_HEADER
> *)((UINTN)UpdatingPtrTrack->StartPtr + ((UINTN)CurrPtr -
> (UINTN)GetStartPointer ((VARIABLE_STORE_HEADER *)ValidBuffer)));
> +      UpdatingPtrTrack->InDeletedTransitionPtr = NULL;
> +    }
> +
> +    CurrPtr += NewVariableSize;
> +  }
> +
> +  if (IsVolatile || mVariableModuleGlobal->VariableGlobal.EmuNvMode) {
> +    //
> +    // If volatile/emulated non-volatile variable store, just copy valid buffer.
> +    //
> +    SetMem ((UINT8 *)(UINTN)VariableBase, VariableStoreHeader->Size, 0xff);
> +    CopyMem ((UINT8 *)(UINTN)VariableBase, ValidBuffer, (UINTN)CurrPtr -
> (UINTN)ValidBuffer);
> +    *LastVariableOffset = (UINTN)CurrPtr - (UINTN)ValidBuffer;
> +    if (!IsVolatile) {
> +      //
> +      // Emulated non-volatile variable mode.
> +      //
> +      mVariableModuleGlobal->HwErrVariableTotalSize      =
> HwErrVariableTotalSize;
> +      mVariableModuleGlobal->CommonVariableTotalSize     =
> CommonVariableTotalSize;
> +      mVariableModuleGlobal->CommonUserVariableTotalSize =
> CommonUserVariableTotalSize;
> +    }
> +
> +    Status = EFI_SUCCESS;
> +  } else {
> +    //
> +    // If non-volatile variable store, perform FTW here.
> +    //
> +    Status = FtwVariableSpace (
> +               VariableBase,
> +               (VARIABLE_STORE_HEADER *)ValidBuffer
> +               );
> +    if (!EFI_ERROR (Status)) {
> +      *LastVariableOffset                                = (UINTN)CurrPtr - (UINTN)ValidBuffer;
> +      mVariableModuleGlobal->HwErrVariableTotalSize      =
> HwErrVariableTotalSize;
> +      mVariableModuleGlobal->CommonVariableTotalSize     =
> CommonVariableTotalSize;
> +      mVariableModuleGlobal->CommonUserVariableTotalSize =
> CommonUserVariableTotalSize;
> +    } else {
> +      mVariableModuleGlobal->HwErrVariableTotalSize      = 0;
> +      mVariableModuleGlobal->CommonVariableTotalSize     = 0;
> +      mVariableModuleGlobal->CommonUserVariableTotalSize = 0;
> +      Variable                                           = GetStartPointer
> ((VARIABLE_STORE_HEADER *)(UINTN)VariableBase);
> +      while (IsValidVariableHeader (Variable, GetEndPointer
> ((VARIABLE_STORE_HEADER *)(UINTN)VariableBase), AuthFormat)) {
> +        NextVariable = GetNextVariablePtr (Variable, AuthFormat);
> +        VariableSize = (UINTN)NextVariable - (UINTN)Variable;
> +        if ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD)
> == EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
> +          mVariableModuleGlobal->HwErrVariableTotalSize += VariableSize;
> +        } else if ((Variable->Attributes &
> EFI_VARIABLE_HARDWARE_ERROR_RECORD) !=
> EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
> +          mVariableModuleGlobal->CommonVariableTotalSize += VariableSize;
> +          if (IsUserVariable (Variable)) {
> +            mVariableModuleGlobal->CommonUserVariableTotalSize +=
> VariableSize;
> +          }
> +        }
> +
> +        Variable = NextVariable;
> +      }
> +
> +      *LastVariableOffset = (UINTN)Variable - (UINTN)VariableBase;
> +    }
> +  }
> +
> +Done:
> +  DoneStatus = EFI_SUCCESS;
> +  if (IsVolatile || mVariableModuleGlobal->VariableGlobal.EmuNvMode) {
> +    DoneStatus = SynchronizeRuntimeVariableCache (
> +                   &mVariableModuleGlobal-
> >VariableGlobal.VariableRuntimeCacheContext.VariableRuntimeVolatileCache,
> +                   0,
> +                   VariableStoreHeader->Size
> +                   );
> +    ASSERT_EFI_ERROR (DoneStatus);
> +    FreePool (ValidBuffer);
> +  } else {
> +    //
> +    // For NV variable reclaim, we use mNvVariableCache as the buffer, so copy
> the data back.
> +    //
> +    CopyMem (mNvVariableCache, (UINT8 *)(UINTN)VariableBase,
> VariableStoreHeader->Size);
> +    DoneStatus = SynchronizeRuntimeVariableCache (
> +                   &mVariableModuleGlobal-
> >VariableGlobal.VariableRuntimeCacheContext.VariableRuntimeNvCache,
> +                   0,
> +                   VariableStoreHeader->Size
> +                   );
> +    ASSERT_EFI_ERROR (DoneStatus);
> +  }
> +
> +  if (!EFI_ERROR (Status) && EFI_ERROR (DoneStatus)) {
> +    Status = DoneStatus;
> +  }
> +
> +  return Status;
> +}
> diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
> index 6c1a3440ac8c..6e86099eb72b 100644
> --- a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
> +++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
> @@ -16,7 +16,7 @@
>    VariableServiceSetVariable() should also check authenticate data to avoid
> buffer overflow,
>    integer overflow. It should also check attribute to avoid authentication bypass.
> 
> -Copyright (c) 2006 - 2020, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
>  (C) Copyright 2015-2018 Hewlett Packard Enterprise Development LP<BR>
>  Copyright (c) Microsoft Corporation.<BR>
>  Copyright (c) 2022, ARM Limited. All rights reserved.<BR>
> @@ -30,7 +30,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
>  #include "VariableParsing.h"
>  #include "VariableRuntimeCache.h"
> 
> -VARIABLE_MODULE_GLOBAL  *mVariableModuleGlobal;
> +VARIABLE_MODULE_GLOBAL  *mVariableModuleGlobal = NULL;
> 
>  ///
>  /// Define a memory cache that improves the search performance for a variable.
> @@ -458,7 +458,7 @@ CalculateCommonUserVariableTotalSize (
>    //
>    if (mEndOfDxe && (mVariableModuleGlobal-
> >CommonMaxUserVariableSpace != mVariableModuleGlobal-
> >CommonVariableSpace)) {
>      Variable = GetStartPointer (mNvVariableCache);
> -    while (IsValidVariableHeader (Variable, GetEndPointer (mNvVariableCache))) {
> +    while (IsValidVariableHeader (Variable, GetEndPointer (mNvVariableCache),
> mVariableModuleGlobal->VariableGlobal.AuthFormat)) {
>        NextVariable = GetNextVariablePtr (Variable, mVariableModuleGlobal-
> >VariableGlobal.AuthFormat);
>        VariableSize = (UINTN)NextVariable - (UINTN)Variable;
>        if ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) !=
> EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
> @@ -497,330 +497,6 @@ InitializeVariableQuota (
>    CalculateCommonUserVariableTotalSize ();
>  }
> 
> -/**
> -
> -  Variable store garbage collection and reclaim operation.
> -
> -  @param[in]      VariableBase            Base address of variable store.
> -  @param[out]     LastVariableOffset      Offset of last variable.
> -  @param[in]      IsVolatile              The variable store is volatile or not;
> -                                          if it is non-volatile, need FTW.
> -  @param[in, out] UpdatingPtrTrack        Pointer to updating variable pointer
> track structure.
> -  @param[in]      NewVariable             Pointer to new variable.
> -  @param[in]      NewVariableSize         New variable size.
> -
> -  @return EFI_SUCCESS                  Reclaim operation has finished successfully.
> -  @return EFI_OUT_OF_RESOURCES         No enough memory resources or
> variable space.
> -  @return Others                       Unexpect error happened during reclaim
> operation.
> -
> -**/
> -EFI_STATUS
> -Reclaim (
> -  IN     EFI_PHYSICAL_ADDRESS    VariableBase,
> -  OUT    UINTN                   *LastVariableOffset,
> -  IN     BOOLEAN                 IsVolatile,
> -  IN OUT VARIABLE_POINTER_TRACK  *UpdatingPtrTrack,
> -  IN     VARIABLE_HEADER         *NewVariable,
> -  IN     UINTN                   NewVariableSize
> -  )
> -{
> -  VARIABLE_HEADER        *Variable;
> -  VARIABLE_HEADER        *AddedVariable;
> -  VARIABLE_HEADER        *NextVariable;
> -  VARIABLE_HEADER        *NextAddedVariable;
> -  VARIABLE_STORE_HEADER  *VariableStoreHeader;
> -  UINT8                  *ValidBuffer;
> -  UINTN                  MaximumBufferSize;
> -  UINTN                  VariableSize;
> -  UINTN                  NameSize;
> -  UINT8                  *CurrPtr;
> -  VOID                   *Point0;
> -  VOID                   *Point1;
> -  BOOLEAN                FoundAdded;
> -  EFI_STATUS             Status;
> -  EFI_STATUS             DoneStatus;
> -  UINTN                  CommonVariableTotalSize;
> -  UINTN                  CommonUserVariableTotalSize;
> -  UINTN                  HwErrVariableTotalSize;
> -  VARIABLE_HEADER        *UpdatingVariable;
> -  VARIABLE_HEADER        *UpdatingInDeletedTransition;
> -  BOOLEAN                AuthFormat;
> -
> -  AuthFormat                  = mVariableModuleGlobal->VariableGlobal.AuthFormat;
> -  UpdatingVariable            = NULL;
> -  UpdatingInDeletedTransition = NULL;
> -  if (UpdatingPtrTrack != NULL) {
> -    UpdatingVariable            = UpdatingPtrTrack->CurrPtr;
> -    UpdatingInDeletedTransition = UpdatingPtrTrack->InDeletedTransitionPtr;
> -  }
> -
> -  VariableStoreHeader = (VARIABLE_STORE_HEADER *)((UINTN)VariableBase);
> -
> -  CommonVariableTotalSize     = 0;
> -  CommonUserVariableTotalSize = 0;
> -  HwErrVariableTotalSize      = 0;
> -
> -  if (IsVolatile || mVariableModuleGlobal->VariableGlobal.EmuNvMode) {
> -    //
> -    // Start Pointers for the variable.
> -    //
> -    Variable          = GetStartPointer (VariableStoreHeader);
> -    MaximumBufferSize = sizeof (VARIABLE_STORE_HEADER);
> -
> -    while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader)))
> {
> -      NextVariable = GetNextVariablePtr (Variable, AuthFormat);
> -      if (((Variable->State == VAR_ADDED) || (Variable->State ==
> (VAR_IN_DELETED_TRANSITION & VAR_ADDED))) &&
> -          (Variable != UpdatingVariable) &&
> -          (Variable != UpdatingInDeletedTransition)
> -          )
> -      {
> -        VariableSize       = (UINTN)NextVariable - (UINTN)Variable;
> -        MaximumBufferSize += VariableSize;
> -      }
> -
> -      Variable = NextVariable;
> -    }
> -
> -    if (NewVariable != NULL) {
> -      //
> -      // Add the new variable size.
> -      //
> -      MaximumBufferSize += NewVariableSize;
> -    }
> -
> -    //
> -    // Reserve the 1 Bytes with Oxff to identify the
> -    // end of the variable buffer.
> -    //
> -    MaximumBufferSize += 1;
> -    ValidBuffer        = AllocatePool (MaximumBufferSize);
> -    if (ValidBuffer == NULL) {
> -      return EFI_OUT_OF_RESOURCES;
> -    }
> -  } else {
> -    //
> -    // For NV variable reclaim, don't allocate pool here and just use
> mNvVariableCache
> -    // as the buffer to reduce SMRAM consumption for SMM variable driver.
> -    //
> -    MaximumBufferSize = mNvVariableCache->Size;
> -    ValidBuffer       = (UINT8 *)mNvVariableCache;
> -  }
> -
> -  SetMem (ValidBuffer, MaximumBufferSize, 0xff);
> -
> -  //
> -  // Copy variable store header.
> -  //
> -  CopyMem (ValidBuffer, VariableStoreHeader, sizeof
> (VARIABLE_STORE_HEADER));
> -  CurrPtr = (UINT8 *)GetStartPointer ((VARIABLE_STORE_HEADER *)ValidBuffer);
> -
> -  //
> -  // Reinstall all ADDED variables as long as they are not identical to Updating
> Variable.
> -  //
> -  Variable = GetStartPointer (VariableStoreHeader);
> -  while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader)))
> {
> -    NextVariable = GetNextVariablePtr (Variable, AuthFormat);
> -    if ((Variable != UpdatingVariable) && (Variable->State == VAR_ADDED)) {
> -      VariableSize = (UINTN)NextVariable - (UINTN)Variable;
> -      CopyMem (CurrPtr, (UINT8 *)Variable, VariableSize);
> -      CurrPtr += VariableSize;
> -      if ((!IsVolatile) && ((Variable->Attributes &
> EFI_VARIABLE_HARDWARE_ERROR_RECORD) ==
> EFI_VARIABLE_HARDWARE_ERROR_RECORD)) {
> -        HwErrVariableTotalSize += VariableSize;
> -      } else if ((!IsVolatile) && ((Variable->Attributes &
> EFI_VARIABLE_HARDWARE_ERROR_RECORD) !=
> EFI_VARIABLE_HARDWARE_ERROR_RECORD)) {
> -        CommonVariableTotalSize += VariableSize;
> -        if (IsUserVariable (Variable)) {
> -          CommonUserVariableTotalSize += VariableSize;
> -        }
> -      }
> -    }
> -
> -    Variable = NextVariable;
> -  }
> -
> -  //
> -  // Reinstall all in delete transition variables.
> -  //
> -  Variable = GetStartPointer (VariableStoreHeader);
> -  while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader)))
> {
> -    NextVariable = GetNextVariablePtr (Variable, AuthFormat);
> -    if ((Variable != UpdatingVariable) && (Variable !=
> UpdatingInDeletedTransition) && (Variable->State ==
> (VAR_IN_DELETED_TRANSITION & VAR_ADDED))) {
> -      //
> -      // Buffer has cached all ADDED variable.
> -      // Per IN_DELETED variable, we have to guarantee that
> -      // no ADDED one in previous buffer.
> -      //
> -
> -      FoundAdded    = FALSE;
> -      AddedVariable = GetStartPointer ((VARIABLE_STORE_HEADER *)ValidBuffer);
> -      while (IsValidVariableHeader (AddedVariable, GetEndPointer
> ((VARIABLE_STORE_HEADER *)ValidBuffer))) {
> -        NextAddedVariable = GetNextVariablePtr (AddedVariable, AuthFormat);
> -        NameSize          = NameSizeOfVariable (AddedVariable, AuthFormat);
> -        if (CompareGuid (
> -              GetVendorGuidPtr (AddedVariable, AuthFormat),
> -              GetVendorGuidPtr (Variable, AuthFormat)
> -              ) && (NameSize == NameSizeOfVariable (Variable, AuthFormat)))
> -        {
> -          Point0 = (VOID *)GetVariableNamePtr (AddedVariable, AuthFormat);
> -          Point1 = (VOID *)GetVariableNamePtr (Variable, AuthFormat);
> -          if (CompareMem (Point0, Point1, NameSize) == 0) {
> -            FoundAdded = TRUE;
> -            break;
> -          }
> -        }
> -
> -        AddedVariable = NextAddedVariable;
> -      }
> -
> -      if (!FoundAdded) {
> -        //
> -        // Promote VAR_IN_DELETED_TRANSITION to VAR_ADDED.
> -        //
> -        VariableSize = (UINTN)NextVariable - (UINTN)Variable;
> -        CopyMem (CurrPtr, (UINT8 *)Variable, VariableSize);
> -        ((VARIABLE_HEADER *)CurrPtr)->State = VAR_ADDED;
> -        CurrPtr                            += VariableSize;
> -        if ((!IsVolatile) && ((Variable->Attributes &
> EFI_VARIABLE_HARDWARE_ERROR_RECORD) ==
> EFI_VARIABLE_HARDWARE_ERROR_RECORD)) {
> -          HwErrVariableTotalSize += VariableSize;
> -        } else if ((!IsVolatile) && ((Variable->Attributes &
> EFI_VARIABLE_HARDWARE_ERROR_RECORD) !=
> EFI_VARIABLE_HARDWARE_ERROR_RECORD)) {
> -          CommonVariableTotalSize += VariableSize;
> -          if (IsUserVariable (Variable)) {
> -            CommonUserVariableTotalSize += VariableSize;
> -          }
> -        }
> -      }
> -    }
> -
> -    Variable = NextVariable;
> -  }
> -
> -  //
> -  // Install the new variable if it is not NULL.
> -  //
> -  if (NewVariable != NULL) {
> -    if (((UINTN)CurrPtr - (UINTN)ValidBuffer) + NewVariableSize >
> VariableStoreHeader->Size) {
> -      //
> -      // No enough space to store the new variable.
> -      //
> -      Status = EFI_OUT_OF_RESOURCES;
> -      goto Done;
> -    }
> -
> -    if (!IsVolatile) {
> -      if ((NewVariable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD)
> == EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
> -        HwErrVariableTotalSize += NewVariableSize;
> -      } else if ((NewVariable->Attributes &
> EFI_VARIABLE_HARDWARE_ERROR_RECORD) !=
> EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
> -        CommonVariableTotalSize += NewVariableSize;
> -        if (IsUserVariable (NewVariable)) {
> -          CommonUserVariableTotalSize += NewVariableSize;
> -        }
> -      }
> -
> -      if ((HwErrVariableTotalSize > PcdGet32 (PcdHwErrStorageSize)) ||
> -          (CommonVariableTotalSize > mVariableModuleGlobal-
> >CommonVariableSpace) ||
> -          (CommonUserVariableTotalSize > mVariableModuleGlobal-
> >CommonMaxUserVariableSpace))
> -      {
> -        //
> -        // No enough space to store the new variable by NV or NV+HR attribute.
> -        //
> -        Status = EFI_OUT_OF_RESOURCES;
> -        goto Done;
> -      }
> -    }
> -
> -    CopyMem (CurrPtr, (UINT8 *)NewVariable, NewVariableSize);
> -    ((VARIABLE_HEADER *)CurrPtr)->State = VAR_ADDED;
> -    if (UpdatingVariable != NULL) {
> -      UpdatingPtrTrack->CurrPtr                = (VARIABLE_HEADER
> *)((UINTN)UpdatingPtrTrack->StartPtr + ((UINTN)CurrPtr -
> (UINTN)GetStartPointer ((VARIABLE_STORE_HEADER *)ValidBuffer)));
> -      UpdatingPtrTrack->InDeletedTransitionPtr = NULL;
> -    }
> -
> -    CurrPtr += NewVariableSize;
> -  }
> -
> -  if (IsVolatile || mVariableModuleGlobal->VariableGlobal.EmuNvMode) {
> -    //
> -    // If volatile/emulated non-volatile variable store, just copy valid buffer.
> -    //
> -    SetMem ((UINT8 *)(UINTN)VariableBase, VariableStoreHeader->Size, 0xff);
> -    CopyMem ((UINT8 *)(UINTN)VariableBase, ValidBuffer, (UINTN)CurrPtr -
> (UINTN)ValidBuffer);
> -    *LastVariableOffset = (UINTN)CurrPtr - (UINTN)ValidBuffer;
> -    if (!IsVolatile) {
> -      //
> -      // Emulated non-volatile variable mode.
> -      //
> -      mVariableModuleGlobal->HwErrVariableTotalSize      =
> HwErrVariableTotalSize;
> -      mVariableModuleGlobal->CommonVariableTotalSize     =
> CommonVariableTotalSize;
> -      mVariableModuleGlobal->CommonUserVariableTotalSize =
> CommonUserVariableTotalSize;
> -    }
> -
> -    Status = EFI_SUCCESS;
> -  } else {
> -    //
> -    // If non-volatile variable store, perform FTW here.
> -    //
> -    Status = FtwVariableSpace (
> -               VariableBase,
> -               (VARIABLE_STORE_HEADER *)ValidBuffer
> -               );
> -    if (!EFI_ERROR (Status)) {
> -      *LastVariableOffset                                = (UINTN)CurrPtr - (UINTN)ValidBuffer;
> -      mVariableModuleGlobal->HwErrVariableTotalSize      =
> HwErrVariableTotalSize;
> -      mVariableModuleGlobal->CommonVariableTotalSize     =
> CommonVariableTotalSize;
> -      mVariableModuleGlobal->CommonUserVariableTotalSize =
> CommonUserVariableTotalSize;
> -    } else {
> -      mVariableModuleGlobal->HwErrVariableTotalSize      = 0;
> -      mVariableModuleGlobal->CommonVariableTotalSize     = 0;
> -      mVariableModuleGlobal->CommonUserVariableTotalSize = 0;
> -      Variable                                           = GetStartPointer
> ((VARIABLE_STORE_HEADER *)(UINTN)VariableBase);
> -      while (IsValidVariableHeader (Variable, GetEndPointer
> ((VARIABLE_STORE_HEADER *)(UINTN)VariableBase))) {
> -        NextVariable = GetNextVariablePtr (Variable, AuthFormat);
> -        VariableSize = (UINTN)NextVariable - (UINTN)Variable;
> -        if ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) ==
> EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
> -          mVariableModuleGlobal->HwErrVariableTotalSize += VariableSize;
> -        } else if ((Variable->Attributes &
> EFI_VARIABLE_HARDWARE_ERROR_RECORD) !=
> EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
> -          mVariableModuleGlobal->CommonVariableTotalSize += VariableSize;
> -          if (IsUserVariable (Variable)) {
> -            mVariableModuleGlobal->CommonUserVariableTotalSize += VariableSize;
> -          }
> -        }
> -
> -        Variable = NextVariable;
> -      }
> -
> -      *LastVariableOffset = (UINTN)Variable - (UINTN)VariableBase;
> -    }
> -  }
> -
> -Done:
> -  DoneStatus = EFI_SUCCESS;
> -  if (IsVolatile || mVariableModuleGlobal->VariableGlobal.EmuNvMode) {
> -    DoneStatus = SynchronizeRuntimeVariableCache (
> -                   &mVariableModuleGlobal-
> >VariableGlobal.VariableRuntimeCacheContext.VariableRuntimeVolatileCache,
> -                   0,
> -                   VariableStoreHeader->Size
> -                   );
> -    ASSERT_EFI_ERROR (DoneStatus);
> -    FreePool (ValidBuffer);
> -  } else {
> -    //
> -    // For NV variable reclaim, we use mNvVariableCache as the buffer, so copy
> the data back.
> -    //
> -    CopyMem (mNvVariableCache, (UINT8 *)(UINTN)VariableBase,
> VariableStoreHeader->Size);
> -    DoneStatus = SynchronizeRuntimeVariableCache (
> -                   &mVariableModuleGlobal-
> >VariableGlobal.VariableRuntimeCacheContext.VariableRuntimeNvCache,
> -                   0,
> -                   VariableStoreHeader->Size
> -                   );
> -    ASSERT_EFI_ERROR (DoneStatus);
> -  }
> -
> -  if (!EFI_ERROR (Status) && EFI_ERROR (DoneStatus)) {
> -    Status = DoneStatus;
> -  }
> -
> -  return Status;
> -}
> -
>  /**
>    Finds variable in storage blocks of volatile and non-volatile storage areas.
> 
> @@ -1657,9 +1333,665 @@ AutoUpdateLangVariable (
>  }
> 
>  /**
> -  Update the variable region with Variable information. If
> EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS is set,
> -  index of associated public key is needed.
> +  Check if there's enough free space in storage to write the new variable.
> 
> +  @param[in] NewVariable        Pointer to buffer of new variable.
> +  @param[in] VariableSize       Size of new variable.
> +  @param[in] VariableName       Name of variable.
> +  @param[in] VendorGuid         Guid of variable.
> +  @param[in] Attributes         Attributes of the variable.
> +  @param[in] VolatileFlag       Volatile/non-volatile variable indicator.
> +
> +  @retval EFI_SUCCESS           Enough free space on variable storage.
> +  @retval EFI_BUFFER_TOO_SMALL  There's not enough continuous free space.
> +  @retval EFI_OUT_OF_RESOURCES  There's not enough free space in total.
> +**/
> +EFI_STATUS
> +CheckVariableStoreSpace (
> +  IN  VARIABLE_HEADER  *NewVariable,
> +  IN  UINTN            VariableSize,
> +  IN  CHAR16           *VariableName,
> +  IN  EFI_GUID         *VendorGuid,
> +  IN  UINT32           Attributes,
> +  IN  BOOLEAN          VolatileFlag
> +  )
> +{
> +  BOOLEAN                IsCommonVariable;
> +  BOOLEAN                IsCommonUserVariable;
> +  UINTN                  CommonVariableTotalSize;
> +  UINTN                  CommonUserVariableTotalSize;
> +  UINTN                  HwErrVariableTotalSize;
> +  VARIABLE_STORE_HEADER  *VarStore;
> +
> +  if ((NewVariable == NULL) || (VariableSize == 0)) {
> +    return EFI_SUCCESS;
> +  }
> +
> +  if (VolatileFlag) {
> +    VarStore = (VARIABLE_STORE_HEADER *)(UINTN)
> +               mVariableModuleGlobal->VariableGlobal.VolatileVariableBase;
> +    if ((UINT32)(VariableSize + mVariableModuleGlobal-
> >VolatileLastVariableOffset)
> +        > VarStore->Size)
> +    {
> +      return EFI_BUFFER_TOO_SMALL;
> +    }
> +  } else {
> +    if ((Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) == 0) {
> +      IsCommonVariable     = TRUE;
> +      IsCommonUserVariable = IsUserVariable (NewVariable);
> +    } else {
> +      IsCommonVariable     = FALSE;
> +      IsCommonUserVariable = FALSE;
> +    }
> +
> +    CommonVariableTotalSize     = mVariableModuleGlobal-
> >CommonVariableTotalSize + VariableSize;
> +    CommonUserVariableTotalSize = mVariableModuleGlobal-
> >CommonUserVariableTotalSize + VariableSize;
> +    HwErrVariableTotalSize      = mVariableModuleGlobal-
> >HwErrVariableTotalSize + VariableSize;
> +
> +    if (  (((Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) != 0) &&
> +           (HwErrVariableTotalSize > PcdGet32 (PcdHwErrStorageSize)))
> +       || (IsCommonVariable && (CommonVariableTotalSize >
> mVariableModuleGlobal->CommonVariableSpace))
> +       || (IsCommonVariable &&
> +           AtRuntime () &&
> +           (CommonVariableTotalSize > mVariableModuleGlobal-
> >CommonRuntimeVariableSpace))
> +       || (IsCommonUserVariable &&
> +           (CommonUserVariableTotalSize > mVariableModuleGlobal-
> >CommonMaxUserVariableSpace)))
> +    {
> +      if (AtRuntime ()) {
> +        if (IsCommonUserVariable &&
> +            ((VariableSize + mVariableModuleGlobal-
> >CommonUserVariableTotalSize)
> +             > mVariableModuleGlobal->CommonMaxUserVariableSpace))
> +        {
> +          RecordVarErrorFlag (
> +            VAR_ERROR_FLAG_USER_ERROR,
> +            VariableName,
> +            VendorGuid,
> +            Attributes,
> +            VariableSize
> +            );
> +        }
> +
> +        if (IsCommonVariable &&
> +            ((VariableSize + mVariableModuleGlobal->CommonVariableTotalSize)
> +             > mVariableModuleGlobal->CommonRuntimeVariableSpace))
> +        {
> +          RecordVarErrorFlag (
> +            VAR_ERROR_FLAG_SYSTEM_ERROR,
> +            VariableName,
> +            VendorGuid,
> +            Attributes,
> +            VariableSize
> +            );
> +        }
> +
> +        return EFI_OUT_OF_RESOURCES;
> +      }
> +
> +      return EFI_BUFFER_TOO_SMALL;
> +    }
> +  }
> +
> +  return EFI_SUCCESS;
> +}
> +
> +/**
> +  Fill specific data of auth-variable in buffer.
> +
> +  @param[in,out]  NewVariable        Pointer to buffer of new variable.
> +  @param[in]      OldVariable        Pointer to buffer of old copy of the variable.
> +  @param[in]      Attributes         Attributes of the variable.
> +  @param[in]      KeyIndex           Index of associated public key.
> +  @param[in]      MonotonicCount     Value of associated monotonic count.
> +  @param[in]      TimeStamp          Value of associated TimeStamp.
> +
> +**/
> +VOID
> +SetVariableAuthData (
> +  IN  OUT AUTHENTICATED_VARIABLE_HEADER  *NewVariable,
> +  IN      AUTHENTICATED_VARIABLE_HEADER  *OldVariable,
> +  IN      UINT32                         Attributes,
> +  IN      UINT32                         KeyIndex,
> +  IN      UINT64                         MonotonicCount,
> +  IN      EFI_TIME                       *TimeStamp
> +  )
> +{
> +  NewVariable->PubKeyIndex    = KeyIndex;
> +  NewVariable->MonotonicCount = MonotonicCount;
> +
> +  if ((TimeStamp != NULL) &&
> +      ((Attributes &
> EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) != 0))
> +  {
> +    //
> +    // In the case when the EFI_VARIABLE_APPEND_WRITE attribute is set, only
> +    // when the new TimeStamp value is later than the current timestamp
> associated
> +    // with the variable, we need associate the new timestamp with the updated
> value.
> +    //
> +    if (((Attributes & EFI_VARIABLE_APPEND_WRITE) != 0) &&
> +        (OldVariable != NULL) &&
> +        !VariableCompareTimeStampInternal (&OldVariable->TimeStamp,
> TimeStamp))
> +    {
> +      TimeStamp = &OldVariable->TimeStamp;
> +    }
> +
> +    CopyMem (&NewVariable->TimeStamp, TimeStamp, sizeof (EFI_TIME));
> +  } else {
> +    ZeroMem (&NewVariable->TimeStamp, sizeof (EFI_TIME));
> +  }
> +}
> +
> +/**
> +  Fill the variable data buffer according to variable format on storage.
> +
> +  @param[in,out]  NewVariable        Pointer to buffer of new variable.
> +  @param[in]      OldVariable        Pointer to buffer of old copy of the variable.
> +  @param[in]      VariableName       Name of variable.
> +  @param[in]      VendorGuid         Guid of variable.
> +  @param[in]      Data               Variable data.
> +  @param[in]      DataSize           Size of data. 0 means delete.
> +  @param[in]      Attributes         Attributes of the variable.
> +  @param[in]      KeyIndex           Index of associated public key.
> +  @param[in]      MonotonicCount     Value of associated monotonic count.
> +  @param[in]      TimeStamp          Value of associated TimeStamp.
> +
> +  @retval Size of the new variable.
> +
> +**/
> +UINTN
> +SetVariableData (
> +  IN  OUT VARIABLE_HEADER  *NewVariable,
> +  IN      VARIABLE_HEADER  *OldVariable,
> +  IN      CHAR16           *VariableName,
> +  IN      EFI_GUID         *VendorGuid,
> +  IN      VOID             *Data,
> +  IN      UINTN            DataSize,
> +  IN      UINT32           Attributes,
> +  IN      UINT32           KeyIndex,
> +  IN      UINT64           MonotonicCount,
> +  IN      EFI_TIME         *TimeStamp
> +  )
> +{
> +  EFI_STATUS  Status;
> +  BOOLEAN     AuthFormat;
> +  UINT8       *DataPtr;
> +  UINTN       NameSize;
> +  UINTN       OldDataSize;
> +
> +  AuthFormat = mVariableModuleGlobal->VariableGlobal.AuthFormat;
> +
> +  if (AuthFormat) {
> +    SetVariableAuthData (
> +      (AUTHENTICATED_VARIABLE_HEADER *)NewVariable,
> +      (AUTHENTICATED_VARIABLE_HEADER *)OldVariable,
> +      Attributes,
> +      KeyIndex,
> +      MonotonicCount,
> +      TimeStamp
> +      );
> +  }
> +
> +  NewVariable->StartId    = VARIABLE_DATA;
> +  NewVariable->State      = VAR_ADDED;
> +  NewVariable->Reserved   = 0;
> +  NewVariable->Attributes = Attributes & (~EFI_VARIABLE_APPEND_WRITE);
> +
> +  CopyMem (
> +    GetVendorGuidPtr (NewVariable, AuthFormat),
> +    VendorGuid,
> +    sizeof (EFI_GUID)
> +    );
> +
> +  NameSize = StrSize (VariableName);
> +  SetNameSizeOfVariable (NewVariable, NameSize, AuthFormat);
> +  CopyMem (
> +    (UINT8 *)GetVariableNamePtr (NewVariable, AuthFormat),
> +    VariableName,
> +    NameSize
> +    );
> +
> +  //
> +  // Set data size first otherwise we can't get correct data pointer in the
> +  // buffer of new variable.
> +  //
> +  SetDataSizeOfVariable (NewVariable, DataSize, AuthFormat);
> +  DataPtr = GetVariableDataPtr (NewVariable, AuthFormat);
> +  if (((Attributes & EFI_VARIABLE_APPEND_WRITE) != 0) &&
> +      (OldVariable != NULL) &&
> +      ((OldVariable->State == VAR_ADDED) ||
> +       (OldVariable->State == (VAR_ADDED & VAR_IN_DELETED_TRANSITION))))
> +  {
> +    //
> +    // Get old data, which might be encrypted.
> +    //
> +    OldDataSize = mVariableModuleGlobal->ScratchBufferSize
> +                  - ((UINTN)DataPtr - (UINTN)NewVariable);
> +    Status = ProtectedVariableLibGetByBuffer (
> +               OldVariable,
> +               DataPtr,
> +               (UINT32 *)&OldDataSize,
> +               AuthFormat
> +               );
> +    if (Status == EFI_UNSUPPORTED) {
> +      OldDataSize = DataSizeOfVariable (OldVariable, AuthFormat);
> +      CopyMem (DataPtr, GetVariableDataPtr (OldVariable, AuthFormat),
> OldDataSize);
> +    } else if (EFI_ERROR (Status)) {
> +      ASSERT_EFI_ERROR (Status);
> +      return 0;
> +    }
> +
> +    DataPtr += OldDataSize;
> +    //
> +    // Update data size.
> +    //
> +    SetDataSizeOfVariable (NewVariable, DataSize + OldDataSize, AuthFormat);
> +  }
> +
> +  CopyMem (DataPtr, Data, DataSize);
> +
> +  //
> +  // The actual size of the variable stored in storage should include padding.
> +  //
> +  return ((UINTN)GetNextVariablePtr (NewVariable, AuthFormat) -
> (UINTN)NewVariable);
> +}
> +
> +/**
> +  Update state of given variable as well as its cached copy.
> +
> +  @param[in,out]  Variable        Pointer to the buffer of the variable.
> +  @param[in,out]  CacheVariable   Cache copy of the variable.
> +  @param[in]      NewState        New state value.
> +  @param[in]      Volatile        Volatile/non-volatile variable indicator.
> +
> +  @retval EFI_SUCCESS     Variable state was updated successfully.
> +  @retval Others          Failed to update the variable state.
> +
> +**/
> +EFI_STATUS
> +UpdateVariableState (
> +  IN  OUT VARIABLE_HEADER  *Variable,
> +  IN  OUT VARIABLE_HEADER  *CacheVariable,
> +  IN      UINT8            NewState,
> +  IN      BOOLEAN          Volatile
> +  )
> +{
> +  EFI_STATUS  Status;
> +
> +  Status = UpdateVariableStore (
> +             &mVariableModuleGlobal->VariableGlobal,
> +             Volatile,
> +             FALSE,
> +             mVariableModuleGlobal->FvbInstance,
> +             (UINTN)&Variable->State,
> +             sizeof (NewState),
> +             &NewState
> +             );
> +  if (!EFI_ERROR (Status) && (CacheVariable != NULL)) {
> +    CacheVariable->State = NewState;
> +  }
> +
> +  return Status;
> +}
> +
> +/**
> +  Flush variable data to variable storage.
> +
> +  @param[in]      VarStoreBase    Base address of variable storage.
> +  @param[in,out]  Offset          Offset to write the variable from.
> +                                  Offset from where next variable can be written.
> +  @param[in,out]  NewVariable     Pointer to the buffer of new variable.
> +  @param[in]      VariableSize    Size of new variable.
> +  @param[in]      Volatile        Volatile/non-volatile variable indicator.
> +  @param[in]      AuthFormat      Auth-variable indicator.
> +
> +  @retval EFI_SUCCESS     Variable(s) were written successfully.
> +  @retval Others          Failed to write the variable data.
> +
> +**/
> +EFI_STATUS
> +WriteVariable (
> +  IN  EFI_PHYSICAL_ADDRESS  VarStoreBase,
> +  IN  OUT UINTN             *Offset,
> +  IN  OUT VARIABLE_HEADER   **NewVariable,
> +  IN      UINT32            VariableSize,
> +  IN      BOOLEAN           Volatile,
> +  IN      BOOLEAN           AuthFormat
> +  )
> +{
> +  EFI_STATUS  Status;
> +
> +  struct {
> +    UINTN     Offset;
> +    UINT8     *Buffer;
> +    UINT32    Size;
> +    UINT8     State;
> +  }                   WriteSteps[4];
> +  UINTN            Index;
> +  UINTN            Steps;
> +  VARIABLE_HEADER  *Variable;
> +
> +  Variable = *NewVariable;
> +  if (Volatile) {
> +    //
> +    // For non-volatile variable, one step only :
> +    //
> +    WriteSteps[0].Offset = *Offset;
> +    WriteSteps[0].Buffer = (UINT8 *)Variable;
> +    WriteSteps[0].Size   = VariableSize;
> +
> +    Steps = 1;
> +  } else {
> +    //
> +    // Four steps for non-volatile variable:
> +    //
> +    // 1. Write variable header
> +    // 2. Set variable state to header valid
> +    // 3. Write variable name and data
> +    // 4. Set variable state to valid
> +    //
> +    Variable->State      = 0xff;
> +    WriteSteps[0].Offset = *Offset;
> +    WriteSteps[0].Buffer = (UINT8 *)Variable;
> +    WriteSteps[0].Size   = (UINT32)GetVariableHeaderSize (AuthFormat);
> +
> +    WriteSteps[1].State  = VAR_HEADER_VALID_ONLY;
> +    WriteSteps[1].Offset = *Offset + OFFSET_OF (VARIABLE_HEADER, State);
> +    WriteSteps[1].Buffer = &WriteSteps[1].State;
> +    WriteSteps[1].Size   = sizeof (Variable->State);
> +
> +    WriteSteps[2].Offset = *Offset + GetVariableHeaderSize (AuthFormat);
> +    WriteSteps[2].Buffer = (UINT8 *)Variable + GetVariableHeaderSize
> (AuthFormat);
> +    WriteSteps[2].Size   = VariableSize - (UINT32)GetVariableHeaderSize
> (AuthFormat);
> +
> +    WriteSteps[3].State  = VAR_ADDED;
> +    WriteSteps[3].Offset = *Offset + OFFSET_OF (VARIABLE_HEADER, State);
> +    WriteSteps[3].Buffer = &WriteSteps[3].State;
> +    WriteSteps[3].Size   = sizeof (Variable->State);
> +
> +    Steps = ARRAY_SIZE (WriteSteps);
> +  }
> +
> +  for (Index = 0; Index < Steps; ++Index) {
> +    Status = UpdateVariableStore (
> +               &mVariableModuleGlobal->VariableGlobal,
> +               Volatile,
> +               TRUE,
> +               mVariableModuleGlobal->FvbInstance,
> +               WriteSteps[Index].Offset,
> +               WriteSteps[Index].Size,
> +               WriteSteps[Index].Buffer
> +               );
> +    if (EFI_ERROR (Status)) {
> +      ASSERT_EFI_ERROR (Status);
> +      return Status;
> +    }
> +  }
> +
> +  Variable->State = VAR_ADDED;
> +  if (!Volatile) {
> +    CopyMem ((UINT8 *)mNvVariableCache + *Offset, Variable, VariableSize);
> +  }
> +
> +  *NewVariable = (VARIABLE_HEADER *)((UINTN)VarStoreBase + *Offset);
> +  *Offset     += HEADER_ALIGN (VariableSize);
> +
> +  return EFI_SUCCESS;
> +}
> +
> +/**
> +  Rebase the given variable pointer(s) to the equivalent one in given variable
> +  storage via VarStore.
> +
> +  @param[in]      InVarTrackPtr     Pointer to current variable in cache.
> +  @param[out]     OutVarTrackPtr    Pointer to rebased variable against VarStore.
> +  @param[in]      VarStore          Start of variable storage to rebase against.
> +  @param[in]      VariableName      Name of variable.
> +  @param[in]      VendorGuid        Guid of variable.
> +  @param[in]      ByOffset          If TRUE, don't do variable search in VarStore.
> +
> +  @retval EFI_SUCCESS           Variable(s) were deleted successfully.
> +  @retval EFI_INVALID_PARAMETER Invalid parameters passed.
> +  @retval EFI_NOT_FOUND         Given variable (VariableName & VendorGuid)
> was
> +                                not found in VarStore, if ByOffset is FALSE.
> +
> +**/
> +EFI_STATUS
> +RebaseVariablePtr (
> +  IN      VARIABLE_POINTER_TRACK  *InVarTrackPtr,
> +  OUT VARIABLE_POINTER_TRACK      *OutVarTrackPtr,
> +  IN      VARIABLE_STORE_HEADER   *VarStore,
> +  IN      CHAR16                  *VariableName,
> +  IN      EFI_GUID                *VendorGuid,
> +  IN      BOOLEAN                 ByOffset
> +  )
> +{
> +  EFI_STATUS       Status;
> +  BOOLEAN          AuthFormat;
> +  VARIABLE_HEADER  *NewStart;
> +
> +  if ((InVarTrackPtr == NULL) || (OutVarTrackPtr == NULL) || (VarStore ==
> NULL)) {
> +    ASSERT (InVarTrackPtr != NULL);
> +    ASSERT (OutVarTrackPtr != NULL);
> +    ASSERT (VarStore != NULL);
> +    return EFI_INVALID_PARAMETER;
> +  }
> +
> +  AuthFormat = mVariableModuleGlobal->VariableGlobal.AuthFormat;
> +
> +  if (  (InVarTrackPtr->CurrPtr == NULL)
> +     || (InVarTrackPtr->StartPtr == GetStartPointer (VarStore)))
> +  {
> +    CopyMem (OutVarTrackPtr, InVarTrackPtr, sizeof
> (VARIABLE_POINTER_TRACK));
> +    return EFI_SUCCESS;
> +  }
> +
> +  NewStart = GetStartPointer (VarStore);
> +  if (ByOffset) {
> +    OutVarTrackPtr->CurrPtr = (VARIABLE_HEADER *)
> +                              ((UINTN)NewStart + ((UINTN)InVarTrackPtr->CurrPtr -
> +                                                  (UINTN)InVarTrackPtr->StartPtr));
> +
> +    if (InVarTrackPtr->InDeletedTransitionPtr != NULL) {
> +      OutVarTrackPtr->InDeletedTransitionPtr =
> +        (VARIABLE_HEADER *)((UINTN)NewStart +
> +                            ((UINTN)InVarTrackPtr->InDeletedTransitionPtr -
> +                             (UINTN)InVarTrackPtr->StartPtr));
> +    } else {
> +      OutVarTrackPtr->InDeletedTransitionPtr = NULL;
> +    }
> +
> +    OutVarTrackPtr->StartPtr = NewStart;
> +    OutVarTrackPtr->EndPtr   = GetEndPointer (VarStore);
> +  } else {
> +    OutVarTrackPtr->StartPtr = NewStart;
> +    OutVarTrackPtr->EndPtr   = GetEndPointer (VarStore);
> +
> +    Status = FindVariableEx (VariableName, VendorGuid, FALSE, OutVarTrackPtr,
> AuthFormat);
> +    if ((OutVarTrackPtr->CurrPtr == NULL) || EFI_ERROR (Status)) {
> +      return EFI_NOT_FOUND;
> +    }
> +  }
> +
> +  if (  (VarStore == mNvVariableCache)
> +     || ((UINTN)VarStore == (UINTN)mVariableModuleGlobal-
> >VariableGlobal.NonVolatileVariableBase))
> +  {
> +    OutVarTrackPtr->Volatile = FALSE;
> +  }
> +
> +  return EFI_SUCCESS;
> +}
> +
> +/**
> +  Check if the given variable is from HOB.
> +
> +  @param[in] CacheVariable      Pointer to current variable in cache.
> +
> +  @retval TRUE    The variable is from HOB.
> +  @retval FALSE   The variable is NOT from HOB.
> +
> +**/
> +BOOLEAN
> +IsHobVariable (
> +  IN VARIABLE_POINTER_TRACK  *CacheVariable
> +  )
> +{
> +  VARIABLE_STORE_HEADER  *HobVarStore;
> +
> +  HobVarStore = (VARIABLE_STORE_HEADER *)(UINTN)
> +                mVariableModuleGlobal->VariableGlobal.HobVariableBase;
> +  return (CacheVariable->CurrPtr != NULL &&
> +          HobVarStore != NULL &&
> +          CacheVariable->StartPtr == GetStartPointer (HobVarStore));
> +}
> +
> +/**
> +  Get temporary buffer for a new variable data.
> +
> +  @retval Pointer to the buffer address.
> +
> +**/
> +VARIABLE_HEADER *
> +GetNewVariableBuffer (
> +  VOID
> +  )
> +{
> +  VARIABLE_HEADER        *NewVariable;
> +  VARIABLE_STORE_HEADER  *VarStore;
> +
> +  //
> +  // Tricky part: Use scratch data area at the end of volatile variable store
> +  // as a temporary storage.
> +  //
> +  VarStore = (VARIABLE_STORE_HEADER *)(UINTN)
> +             mVariableModuleGlobal->VariableGlobal.VolatileVariableBase;
> +  NewVariable = GetEndPointer (VarStore);
> +
> +  SetMem (NewVariable, mVariableModuleGlobal->ScratchBufferSize, 0xff);
> +
> +  return NewVariable;
> +}
> +
> +/**
> +  Delete old copies of variable completely.
> +
> +  @param[in]      VariableName       Name of variable.
> +  @param[in]      VendorGuid         Guid of variable.
> +  @param[in]      Variable           Pointer to current variable on storage.
> +  @param[in,out]  CacheVariable      Pointer to current variable in cache.
> +  @param[in]      VolatileFlag       Auth-variable indicator.
> +
> +  @retval EFI_SUCCESS           Variable(s) were deleted successfully.
> +  @retval Others                Failed to update variable state.
> +
> +**/
> +EFI_STATUS
> +DeleteVariable (
> +  IN      CHAR16                  *VariableName,
> +  IN      EFI_GUID                *VendorGuid,
> +  IN      VARIABLE_POINTER_TRACK  *Variable,
> +  IN  OUT VARIABLE_POINTER_TRACK  *CacheVariable,
> +  IN      BOOLEAN                 VolatileFlag
> +  )
> +{
> +  EFI_STATUS  Status;
> +
> +  if (Variable->InDeletedTransitionPtr != NULL) {
> +    ASSERT (CacheVariable->InDeletedTransitionPtr != NULL);
> +    //
> +    // Both ADDED and IN_DELETED_TRANSITION variable are present,
> +    // set IN_DELETED_TRANSITION one to DELETED state first.
> +    //
> +    Status = UpdateVariableState (
> +               Variable->InDeletedTransitionPtr,
> +               CacheVariable->InDeletedTransitionPtr,
> +               CacheVariable->InDeletedTransitionPtr->State & VAR_DELETED,
> +               VolatileFlag
> +               );
> +    if (EFI_ERROR (Status)) {
> +      return Status;
> +    }
> +  }
> +
> +  ASSERT (CacheVariable->CurrPtr != NULL);
> +  Status = UpdateVariableState (
> +             Variable->CurrPtr,
> +             CacheVariable->CurrPtr,
> +             CacheVariable->CurrPtr->State & VAR_DELETED,
> +             VolatileFlag
> +             );
> +
> +  if (!EFI_ERROR (Status)) {
> +    UpdateVariableInfo (
> +      VariableName,
> +      VendorGuid,
> +      Variable->Volatile,
> +      FALSE,
> +      FALSE,
> +      TRUE,
> +      FALSE,
> +      &gVariableInfo
> +      );
> +    if (!Variable->Volatile) {
> +      FlushHobVariableToFlash (VariableName, VendorGuid);
> +    }
> +  }
> +
> +  return Status;
> +}
> +
> +/**
> +  Check if it's the right time to update a variable.
> +
> +  @param[in] Attributes         Attributes of a variable.
> +
> +  @retval TRUE    It's ready for variable update.
> +  @retval FALSE   It's NOT ready for variable update.
> +
> +**/
> +BOOLEAN
> +ReadyForUpdate (
> +  IN UINT32  Attributes
> +  )
> +{
> +  if ((mVariableModuleGlobal->FvbInstance == NULL) &&
> +      !mVariableModuleGlobal->VariableGlobal.EmuNvMode)
> +  {
> +    //
> +    // The FVB protocol is not ready, so the
> EFI_VARIABLE_WRITE_ARCH_PROTOCOL
> +    // is not installed.
> +    //
> +    if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
> +      //
> +      // Trying to update NV variable prior to the installation of
> +      // EFI_VARIABLE_WRITE_ARCH_PROTOCOL
> +      //
> +      DEBUG ((
> +        DEBUG_ERROR,
> +        "Update NV variable before EFI_VARIABLE_WRITE_ARCH_PROTOCOL
> ready - %r\n",
> +        EFI_NOT_AVAILABLE_YET
> +        ));
> +      return FALSE;
> +    } else if ((Attributes & VARIABLE_ATTRIBUTE_AT_AW) != 0) {
> +      //
> +      // Trying to update volatile authenticated variable prior to the
> +      // installation of EFI_VARIABLE_WRITE_ARCH_PROTOCOL. The
> authenticated
> +      // variable perhaps is not initialized, just return here.
> +      //
> +      DEBUG ((
> +        DEBUG_ERROR,
> +        "Update AUTH variable before EFI_VARIABLE_WRITE_ARCH_PROTOCOL
> ready - %r\n",
> +        EFI_NOT_AVAILABLE_YET
> +        ));
> +      return FALSE;
> +    }
> +  }
> +
> +  return TRUE;
> +}
> +
> +/**
> +  Check parameters associated with the variable to update.
> +
> +  @param[in] Variable           Pointer to current variable on storage.
> +  @param[in] CacheVariable      Pointer to current variable in cache.
>    @param[in] VariableName       Name of variable.
>    @param[in] VendorGuid         Guid of variable.
>    @param[in] Data               Variable data.
> @@ -1667,9 +1999,130 @@ AutoUpdateLangVariable (
>    @param[in] Attributes         Attributes of the variable.
>    @param[in] KeyIndex           Index of associated public key.
>    @param[in] MonotonicCount     Value of associated monotonic count.
> -  @param[in, out] CacheVariable The variable information which is used to keep
> track of variable usage.
>    @param[in] TimeStamp          Value of associated TimeStamp.
> 
> +  @retval EFI_SUCCESS           The variable is ok to be updated.
> +  @retval EFI_ALREADY_STARTED   No need to update the variable.
> +  @retval EFI_WRITE_PROTECTED   The variable cannot be updated.
> +  @retval EFI_INVALID_PARAMETER The variable attributes are not valid.
> +  @retval EFI_NOT_FOUND         Trying to delete non-existing variable.
> +
> +**/
> +EFI_STATUS
> +ValidateVariableParameters (
> +  IN VARIABLE_POINTER_TRACK  *Variable,
> +  IN VARIABLE_POINTER_TRACK  *CacheVariable,
> +  IN CHAR16                  *VariableName,
> +  IN EFI_GUID                *VendorGuid,
> +  IN VOID                    *Data,
> +  IN UINTN                   DataSize,
> +  IN UINT32                  Attributes,
> +  IN UINT32                  KeyIndex,
> +  IN UINT64                  MonotonicCount,
> +  IN EFI_TIME                *TimeStamp
> +  )
> +{
> +  BOOLEAN  AuthFlag;
> +
> +  AuthFlag = mVariableModuleGlobal->VariableGlobal.AuthFormat;
> +
> +  if ((DataSize == 0) && ((Attributes & EFI_VARIABLE_APPEND_WRITE) != 0)) {
> +    return EFI_ALREADY_STARTED;
> +  }
> +
> +  if (Variable->CurrPtr != NULL) {
> +    //
> +    // Update/Delete existing variable.
> +    //
> +    if (AtRuntime ()) {
> +      //
> +      // If AtRuntime and the variable is Volatile and Runtime Access,
> +      // the volatile is ReadOnly, and SetVariable should be aborted and
> +      // return EFI_WRITE_PROTECTED.
> +      //
> +      if (Variable->Volatile) {
> +        return EFI_WRITE_PROTECTED;
> +      }
> +
> +      //
> +      // Only variable that have NV attributes can be updated/deleted in Runtime.
> +      //
> +      if ((CacheVariable->CurrPtr->Attributes & EFI_VARIABLE_NON_VOLATILE)
> == 0) {
> +        return EFI_INVALID_PARAMETER;
> +      }
> +
> +      //
> +      // Only variable that have RT attributes can be updated/deleted in Runtime.
> +      //
> +      if ((CacheVariable->CurrPtr->Attributes & EFI_VARIABLE_RUNTIME_ACCESS)
> == 0) {
> +        return EFI_INVALID_PARAMETER;
> +      }
> +    }
> +
> +    //
> +    // Variable content unchanged and no need to update timestamp, just return.
> +    //
> +    if (  ((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0)
> +       && (TimeStamp == NULL)
> +       && (DataSizeOfVariable (CacheVariable->CurrPtr, AuthFlag) == DataSize)
> +       && (CompareMem (Data, GetVariableDataPtr (CacheVariable->CurrPtr,
> AuthFlag), DataSize) == 0))
> +    {
> +      UpdateVariableInfo (
> +        VariableName,
> +        VendorGuid,
> +        Variable->Volatile,
> +        FALSE,
> +        TRUE,
> +        FALSE,
> +        FALSE,
> +        &gVariableInfo
> +        );
> +      return EFI_ALREADY_STARTED;
> +    }
> +  } else {
> +    //
> +    // Create a new variable.
> +    //
> +
> +    //
> +    // Make sure we are trying to create a new variable. You cannot delete a
> new
> +    // variable.
> +    //
> +    if ((DataSize == 0) ||
> +        ((Attributes &
> (EFI_VARIABLE_RUNTIME_ACCESS|EFI_VARIABLE_BOOTSERVICE_ACCESS)) ==
> 0))
> +    {
> +      return EFI_NOT_FOUND;
> +    }
> +
> +    //
> +    // Only variable have NV|RT attribute can be created in Runtime.
> +    //
> +    if (  AtRuntime ()
> +       && (  ((Attributes & EFI_VARIABLE_RUNTIME_ACCESS) == 0)
> +          || ((Attributes & EFI_VARIABLE_NON_VOLATILE) == 0)))
> +    {
> +      return EFI_INVALID_PARAMETER;
> +    }
> +  }
> +
> +  return EFI_SUCCESS;
> +}
> +
> +/**
> +  Update the variable region with Variable information. If
> EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS is set,
> +  index of associated public key is needed.
> +
> +  @param[in]      VariableName       Name of variable.
> +  @param[in]      VendorGuid         Guid of variable.
> +  @param[in]      Data               Variable data.
> +  @param[in]      DataSize           Size of data. 0 means delete.
> +  @param[in]      Attributes         Attributes of the variable.
> +  @param[in]      KeyIndex           Index of associated public key.
> +  @param[in]      MonotonicCount     Value of associated monotonic count.
> +  @param[in,out]  CacheVariable      The variable information which is used
> +                                     to keep track of variable usage.
> +  @param[in]      TimeStamp          Value of associated TimeStamp.
> +
>    @retval EFI_SUCCESS           The update operation is success.
>    @retval EFI_OUT_OF_RESOURCES  Variable region is full, can not write other
> data into this region.
> 
> @@ -1687,710 +2140,381 @@ UpdateVariable (
>    IN      EFI_TIME                *TimeStamp      OPTIONAL
>    )
>  {
> -  EFI_STATUS                          Status;
> -  VARIABLE_HEADER                     *NextVariable;
> -  UINTN                               ScratchSize;
> -  UINTN                               MaxDataSize;
> -  UINTN                               VarNameOffset;
> -  UINTN                               VarDataOffset;
> -  UINTN                               VarNameSize;
> -  UINTN                               VarSize;
> -  BOOLEAN                             Volatile;
> -  EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *Fvb;
> -  UINT8                               State;
> -  VARIABLE_POINTER_TRACK              *Variable;
> -  VARIABLE_POINTER_TRACK              NvVariable;
> -  VARIABLE_STORE_HEADER               *VariableStoreHeader;
> -  VARIABLE_RUNTIME_CACHE              *VolatileCacheInstance;
> -  UINT8                               *BufferForMerge;
> -  UINTN                               MergedBufSize;
> -  BOOLEAN                             DataReady;
> -  UINTN                               DataOffset;
> -  BOOLEAN                             IsCommonVariable;
> -  BOOLEAN                             IsCommonUserVariable;
> -  AUTHENTICATED_VARIABLE_HEADER       *AuthVariable;
> -  BOOLEAN                             AuthFormat;
> +  EFI_STATUS              Status;
> +  VARIABLE_GLOBAL         *VarGlobal;
> +  VARIABLE_HEADER         *NewVariable;
> +  VARIABLE_HEADER         *NextVariable;
> +  VARIABLE_HEADER         *UpdatingVariable;
> +  UINTN                   VarSize;
> +  UINTN                   UpdateSize;
> +  UINTN                   Offset;
> +  VARIABLE_POINTER_TRACK  *Variable;
> +  VARIABLE_POINTER_TRACK  NvVariable;
> +  VARIABLE_STORE_HEADER   *VariableStoreHeader;
> +  VARIABLE_RUNTIME_CACHE  *VolatileCacheInstance;
> +  BOOLEAN                 IsCommonVariable;
> +  BOOLEAN                 IsCommonUserVariable;
> +  BOOLEAN                 DeleteFlag;
> +  BOOLEAN                 VolatileFlag;
> +  BOOLEAN                 HobVarOnlyFlag;
> +  EFI_PHYSICAL_ADDRESS    VarStoreBase;
> +  UINTN                   *LastVariableOffset;
> 
> -  if ((mVariableModuleGlobal->FvbInstance == NULL)
> && !mVariableModuleGlobal->VariableGlobal.EmuNvMode) {
> -    //
> -    // The FVB protocol is not ready, so the
> EFI_VARIABLE_WRITE_ARCH_PROTOCOL is not installed.
> -    //
> -    if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
> -      //
> -      // Trying to update NV variable prior to the installation of
> EFI_VARIABLE_WRITE_ARCH_PROTOCOL
> -      //
> -      DEBUG ((DEBUG_ERROR, "Update NV variable before
> EFI_VARIABLE_WRITE_ARCH_PROTOCOL ready - %r\n",
> EFI_NOT_AVAILABLE_YET));
> -      return EFI_NOT_AVAILABLE_YET;
> -    } else if ((Attributes & VARIABLE_ATTRIBUTE_AT_AW) != 0) {
> -      //
> -      // Trying to update volatile authenticated variable prior to the installation of
> EFI_VARIABLE_WRITE_ARCH_PROTOCOL
> -      // The authenticated variable perhaps is not initialized, just return here.
> -      //
> -      DEBUG ((DEBUG_ERROR, "Update AUTH variable before
> EFI_VARIABLE_WRITE_ARCH_PROTOCOL ready - %r\n",
> EFI_NOT_AVAILABLE_YET));
> -      return EFI_NOT_AVAILABLE_YET;
> -    }
> +  if (!ReadyForUpdate (Attributes)) {
> +    return EFI_NOT_AVAILABLE_YET;
>    }
> 
> -  AuthFormat = mVariableModuleGlobal->VariableGlobal.AuthFormat;
> +  VarGlobal = &mVariableModuleGlobal->VariableGlobal;
> +
> +  if (  (((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0) && (DataSize == 0))
> +     || (Attributes == 0)
> +     || (AtRuntime () && ((Attributes & (EFI_VARIABLE_RUNTIME_ACCESS
> +                                         |EFI_VARIABLE_BOOTSERVICE_ACCESS)) == 0)))
> +  {
> +    DeleteFlag = TRUE;
> +  } else {
> +    DeleteFlag = FALSE;
> +  }
> +
> +  if (  ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0)
> +     || ((CacheVariable->CurrPtr != NULL) &&
> +         ((CacheVariable->CurrPtr->Attributes & EFI_VARIABLE_NON_VOLATILE) !=
> 0)))
> +  {
> +    VolatileFlag = FALSE;
> +  } else {
> +    VolatileFlag = TRUE;
> +  }
> 
>    //
>    // Check if CacheVariable points to the variable in variable HOB.
>    // If yes, let CacheVariable points to the variable in NV variable cache.
>    //
> -  if ((CacheVariable->CurrPtr != NULL) &&
> -      (mVariableModuleGlobal->VariableGlobal.HobVariableBase != 0) &&
> -      (CacheVariable->StartPtr == GetStartPointer ((VARIABLE_STORE_HEADER
> *)(UINTN)mVariableModuleGlobal->VariableGlobal.HobVariableBase))
> -      )
> -  {
> -    CacheVariable->StartPtr = GetStartPointer (mNvVariableCache);
> -    CacheVariable->EndPtr   = GetEndPointer (mNvVariableCache);
> -    CacheVariable->Volatile = FALSE;
> -    Status                  = FindVariableEx (VariableName, VendorGuid, FALSE,
> CacheVariable, AuthFormat);
> +  HobVarOnlyFlag = FALSE;
> +  if (IsHobVariable (CacheVariable)) {
> +    Status = RebaseVariablePtr (
> +               CacheVariable,
> +               CacheVariable,
> +               mNvVariableCache,
> +               VariableName,
> +               VendorGuid,
> +               FALSE
> +               );
>      if ((CacheVariable->CurrPtr == NULL) || EFI_ERROR (Status)) {
>        //
>        // There is no matched variable in NV variable cache.
>        //
> -      if ((((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0) && (DataSize == 0))
> || (Attributes == 0)) {
> +      if (DeleteFlag) {
>          //
> -        // It is to delete variable,
> -        // go to delete this variable in variable HOB and
> -        // try to flush other variables from HOB to flash.
> +        // Leave the deletion to FlushHobVariableToFlash() before return.
>          //
> -        UpdateVariableInfo (VariableName, VendorGuid, FALSE, FALSE, FALSE,
> TRUE, FALSE, &gVariableInfo);
> -        FlushHobVariableToFlash (VariableName, VendorGuid);
> -        return EFI_SUCCESS;
> +        HobVarOnlyFlag = TRUE;
> +        Status         = EFI_SUCCESS;
> +        goto Done;
>        }
>      }
>    }
> 
> +  //
> +  // Determine the physical position of variable store to update, due to cache
> +  // mechanims of variable service.
> +  //
>    if ((CacheVariable->CurrPtr == NULL) || CacheVariable->Volatile) {
> +    //
> +    // - Add new variable (volatile or non-volatile); Or
> +    // - Update/delete volatile variable in place.
> +    //
>      Variable = CacheVariable;
>    } else {
>      //
> -    // Update/Delete existing NV variable.
> -    // CacheVariable points to the variable in the memory copy of Flash area
> -    // Now let Variable points to the same variable in Flash area.
> +    // - Update/Delete existing NV variable.
> +    //    CacheVariable points to the variable in the memory copy of Flash area.
> +    //    Now let Variable points to the same variable in Flash area.
>      //
> -    VariableStoreHeader = (VARIABLE_STORE_HEADER
> *)((UINTN)mVariableModuleGlobal->VariableGlobal.NonVolatileVariableBase);
> -    Variable            = &NvVariable;
> -    Variable->StartPtr  = GetStartPointer (VariableStoreHeader);
> -    Variable->EndPtr    = (VARIABLE_HEADER *)((UINTN)Variable->StartPtr +
> ((UINTN)CacheVariable->EndPtr - (UINTN)CacheVariable->StartPtr));
> -
> -    Variable->CurrPtr = (VARIABLE_HEADER *)((UINTN)Variable->StartPtr +
> ((UINTN)CacheVariable->CurrPtr - (UINTN)CacheVariable->StartPtr));
> -    if (CacheVariable->InDeletedTransitionPtr != NULL) {
> -      Variable->InDeletedTransitionPtr = (VARIABLE_HEADER *)((UINTN)Variable-
> >StartPtr + ((UINTN)CacheVariable->InDeletedTransitionPtr -
> (UINTN)CacheVariable->StartPtr));
> -    } else {
> -      Variable->InDeletedTransitionPtr = NULL;
> -    }
> -
> -    Variable->Volatile = FALSE;
> +    VariableStoreHeader = (VARIABLE_STORE_HEADER *)(UINTN)
> +                          VarGlobal->NonVolatileVariableBase;
> +    Variable = &NvVariable;
> +    Status   = RebaseVariablePtr (
> +                 CacheVariable,
> +                 Variable,
> +                 VariableStoreHeader,
> +                 VariableName,
> +                 VendorGuid,
> +                 TRUE
> +                 );
> +    ASSERT_EFI_ERROR (Status);
>    }
> 
> -  Fvb = mVariableModuleGlobal->FvbInstance;
> -
>    //
> -  // Tricky part: Use scratch data area at the end of volatile variable store
> -  // as a temporary storage.
> +  // Validate variable parameters.
>    //
> -  NextVariable = GetEndPointer ((VARIABLE_STORE_HEADER
> *)((UINTN)mVariableModuleGlobal->VariableGlobal.VolatileVariableBase));
> -  ScratchSize  = mVariableModuleGlobal->ScratchBufferSize;
> -  SetMem (NextVariable, ScratchSize, 0xff);
> -  DataReady = FALSE;
> -
> -  if (Variable->CurrPtr != NULL) {
> -    //
> -    // Update/Delete existing variable.
> -    //
> -    if (AtRuntime ()) {
> -      //
> -      // If AtRuntime and the variable is Volatile and Runtime Access,
> -      // the volatile is ReadOnly, and SetVariable should be aborted and
> -      // return EFI_WRITE_PROTECTED.
> -      //
> -      if (Variable->Volatile) {
> -        Status = EFI_WRITE_PROTECTED;
> -        goto Done;
> -      }
> -
> -      //
> -      // Only variable that have NV attributes can be updated/deleted in Runtime.
> -      //
> -      if ((CacheVariable->CurrPtr->Attributes & EFI_VARIABLE_NON_VOLATILE) ==
> 0) {
> -        Status = EFI_INVALID_PARAMETER;
> -        goto Done;
> -      }
> -
> -      //
> -      // Only variable that have RT attributes can be updated/deleted in Runtime.
> -      //
> -      if ((CacheVariable->CurrPtr->Attributes & EFI_VARIABLE_RUNTIME_ACCESS)
> == 0) {
> -        Status = EFI_INVALID_PARAMETER;
> -        goto Done;
> -      }
> -    }
> -
> -    //
> -    // Setting a data variable with no access, or zero DataSize attributes
> -    // causes it to be deleted.
> -    // When the EFI_VARIABLE_APPEND_WRITE attribute is set, DataSize of zero
> will
> -    // not delete the variable.
> -    //
> -    if ((((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0) && (DataSize == 0)) ||
> ((Attributes & (EFI_VARIABLE_RUNTIME_ACCESS |
> EFI_VARIABLE_BOOTSERVICE_ACCESS)) == 0)) {
> -      if (Variable->InDeletedTransitionPtr != NULL) {
> -        //
> -        // Both ADDED and IN_DELETED_TRANSITION variable are present,
> -        // set IN_DELETED_TRANSITION one to DELETED state first.
> -        //
> -        ASSERT (CacheVariable->InDeletedTransitionPtr != NULL);
> -        State  = CacheVariable->InDeletedTransitionPtr->State;
> -        State &= VAR_DELETED;
> -        Status = UpdateVariableStore (
> -                   &mVariableModuleGlobal->VariableGlobal,
> -                   Variable->Volatile,
> -                   FALSE,
> -                   Fvb,
> -                   (UINTN)&Variable->InDeletedTransitionPtr->State,
> -                   sizeof (UINT8),
> -                   &State
> -                   );
> -        if (!EFI_ERROR (Status)) {
> -          if (!Variable->Volatile) {
> -            CacheVariable->InDeletedTransitionPtr->State = State;
> -          }
> -        } else {
> -          goto Done;
> -        }
> -      }
> -
> -      State  = CacheVariable->CurrPtr->State;
> -      State &= VAR_DELETED;
> -
> -      Status = UpdateVariableStore (
> -                 &mVariableModuleGlobal->VariableGlobal,
> -                 Variable->Volatile,
> -                 FALSE,
> -                 Fvb,
> -                 (UINTN)&Variable->CurrPtr->State,
> -                 sizeof (UINT8),
> -                 &State
> -                 );
> -      if (!EFI_ERROR (Status)) {
> -        UpdateVariableInfo (VariableName, VendorGuid, Variable->Volatile, FALSE,
> FALSE, TRUE, FALSE, &gVariableInfo);
> -        if (!Variable->Volatile) {
> -          CacheVariable->CurrPtr->State = State;
> -          FlushHobVariableToFlash (VariableName, VendorGuid);
> -        }
> -      }
> +  Status = ValidateVariableParameters (
> +             Variable,
> +             CacheVariable,
> +             VariableName,
> +             VendorGuid,
> +             Data,
> +             DataSize,
> +             Attributes,
> +             KeyIndex,
> +             MonotonicCount,
> +             TimeStamp
> +             );
> +  if (EFI_ERROR (Status)) {
> +    goto Done;
> +  }
> 
> -      goto Done;
> -    }
> +  //
> +  // Add or update a variable. Allocate a buffer to hold it temporarily.
> +  //
> +  NewVariable = GetNewVariableBuffer ();
> 
> +  //
> +  // Fill-up variable data first, if necessary.
> +  //
> +  IsCommonVariable     = FALSE;
> +  IsCommonUserVariable = FALSE;
> +  if (DeleteFlag) {
>      //
> -    // If the variable is marked valid, and the same data has been passed in,
> -    // then return to the caller immediately.
> +    // No need to fill up variable buffer when deleting a variable. But the
> +    // buffer is still needed if variable protection is employed.
>      //
> -    if ((DataSizeOfVariable (CacheVariable->CurrPtr, AuthFormat) == DataSize)
> &&
> -        (CompareMem (Data, GetVariableDataPtr (CacheVariable->CurrPtr,
> AuthFormat), DataSize) == 0) &&
> -        ((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0) &&
> -        (TimeStamp == NULL))
> -    {
> -      //
> -      // Variable content unchanged and no need to update timestamp, just return.
> -      //
> -      UpdateVariableInfo (VariableName, VendorGuid, Variable->Volatile, FALSE,
> TRUE, FALSE, FALSE, &gVariableInfo);
> -      Status = EFI_SUCCESS;
> -      goto Done;
> -    } else if ((CacheVariable->CurrPtr->State == VAR_ADDED) ||
> -               (CacheVariable->CurrPtr->State == (VAR_ADDED &
> VAR_IN_DELETED_TRANSITION)))
> -    {
> -      //
> -      // EFI_VARIABLE_APPEND_WRITE attribute only effects for existing variable.
> -      //
> -      if ((Attributes & EFI_VARIABLE_APPEND_WRITE) != 0) {
> -        //
> -        // NOTE: From 0 to DataOffset of NextVariable is reserved for Variable
> Header and Name.
> -        // From DataOffset of NextVariable is to save the existing variable data.
> -        //
> -        DataOffset     = GetVariableDataOffset (CacheVariable->CurrPtr,
> AuthFormat);
> -        BufferForMerge = (UINT8 *)((UINTN)NextVariable + DataOffset);
> -        CopyMem (
> -          BufferForMerge,
> -          (UINT8 *)((UINTN)CacheVariable->CurrPtr + DataOffset),
> -          DataSizeOfVariable (CacheVariable->CurrPtr, AuthFormat)
> -          );
> -
> -        //
> -        // Set Max Auth/Non-Volatile/Volatile Variable Data Size as default
> MaxDataSize.
> -        //
> -        if ((Attributes & VARIABLE_ATTRIBUTE_AT_AW) != 0) {
> -          MaxDataSize = mVariableModuleGlobal->MaxAuthVariableSize -
> DataOffset;
> -        } else if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
> -          MaxDataSize = mVariableModuleGlobal->MaxVariableSize - DataOffset;
> -        } else {
> -          MaxDataSize = mVariableModuleGlobal->MaxVolatileVariableSize -
> DataOffset;
> -        }
> -
> -        //
> -        // Append the new data to the end of existing data.
> -        // Max Harware error record variable data size is different from
> common/auth variable.
> -        //
> -        if ((Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) ==
> EFI_VARIABLE_HARDWARE_ERROR_RECORD) {
> -          MaxDataSize = PcdGet32 (PcdMaxHardwareErrorVariableSize) -
> DataOffset;
> -        }
> -
> -        if (DataSizeOfVariable (CacheVariable->CurrPtr, AuthFormat) + DataSize >
> MaxDataSize) {
> -          //
> -          // Existing data size + new data size exceed maximum variable size
> limitation.
> -          //
> -          Status = EFI_INVALID_PARAMETER;
> -          goto Done;
> -        }
> -
> -        CopyMem (
> -          (UINT8 *)(
> -                    (UINTN)BufferForMerge + DataSizeOfVariable (CacheVariable-
> >CurrPtr, AuthFormat)
> -                    ),
> -          Data,
> -          DataSize
> -          );
> -        MergedBufSize = DataSizeOfVariable (CacheVariable->CurrPtr, AuthFormat)
> +
> -                        DataSize;
> -
> -        //
> -        // BufferForMerge(from DataOffset of NextVariable) has included the
> merged existing and new data.
> -        //
> -        Data      = BufferForMerge;
> -        DataSize  = MergedBufSize;
> -        DataReady = TRUE;
> -      }
> -
> -      //
> -      // Mark the old variable as in delete transition.
> -      //
> -      State  = CacheVariable->CurrPtr->State;
> -      State &= VAR_IN_DELETED_TRANSITION;
> -
> -      Status = UpdateVariableStore (
> -                 &mVariableModuleGlobal->VariableGlobal,
> -                 Variable->Volatile,
> -                 FALSE,
> -                 Fvb,
> -                 (UINTN)&Variable->CurrPtr->State,
> -                 sizeof (UINT8),
> -                 &State
> -                 );
> -      if (EFI_ERROR (Status)) {
> -        goto Done;
> -      }
> -
> -      if (!Variable->Volatile) {
> -        CacheVariable->CurrPtr->State = State;
> -      }
> -    }
> +    VarSize = 0;
>    } else {
> -    //
> -    // Not found existing variable. Create a new variable.
> -    //
> +    VarSize = SetVariableData (
> +                NewVariable,
> +                CacheVariable->CurrPtr,
> +                VariableName,
> +                VendorGuid,
> +                Data,
> +                DataSize,
> +                Attributes,
> +                KeyIndex,
> +                MonotonicCount,
> +                TimeStamp
> +                );
> 
> -    if ((DataSize == 0) && ((Attributes & EFI_VARIABLE_APPEND_WRITE) != 0)) {
> -      Status = EFI_SUCCESS;
> -      goto Done;
> -    }
> -
> -    //
> -    // Make sure we are trying to create a new variable.
> -    // Setting a data variable with zero DataSize or no access attributes means to
> delete it.
> -    //
> -    if ((DataSize == 0) || ((Attributes & (EFI_VARIABLE_RUNTIME_ACCESS |
> EFI_VARIABLE_BOOTSERVICE_ACCESS)) == 0)) {
> -      Status = EFI_NOT_FOUND;
> -      goto Done;
> -    }
> -
> -    //
> -    // Only variable have NV|RT attribute can be created in Runtime.
> -    //
> -    if (AtRuntime () &&
> -        (((Attributes & EFI_VARIABLE_RUNTIME_ACCESS) == 0) || ((Attributes &
> EFI_VARIABLE_NON_VOLATILE) == 0)))
> -    {
> -      Status = EFI_INVALID_PARAMETER;
> -      goto Done;
> -    }
> -  }
> -
> -  //
> -  // Function part - create a new variable and copy the data.
> -  // Both update a variable and create a variable will come here.
> -  //
> -  NextVariable->StartId = VARIABLE_DATA;
> -  //
> -  // NextVariable->State = VAR_ADDED;
> -  //
> -  NextVariable->Reserved = 0;
> -  if (mVariableModuleGlobal->VariableGlobal.AuthFormat) {
> -    AuthVariable                 = (AUTHENTICATED_VARIABLE_HEADER
> *)NextVariable;
> -    AuthVariable->PubKeyIndex    = KeyIndex;
> -    AuthVariable->MonotonicCount = MonotonicCount;
> -    ZeroMem (&AuthVariable->TimeStamp, sizeof (EFI_TIME));
> -
> -    if (((Attributes &
> EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) != 0) &&
> -        (TimeStamp != NULL))
> -    {
> -      if ((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0) {
> -        CopyMem (&AuthVariable->TimeStamp, TimeStamp, sizeof (EFI_TIME));
> -      } else {
> -        //
> -        // In the case when the EFI_VARIABLE_APPEND_WRITE attribute is set,
> only
> -        // when the new TimeStamp value is later than the current timestamp
> associated
> -        // with the variable, we need associate the new timestamp with the
> updated value.
> -        //
> -        if (Variable->CurrPtr != NULL) {
> -          if (VariableCompareTimeStampInternal
> (&(((AUTHENTICATED_VARIABLE_HEADER *)CacheVariable->CurrPtr)-
> >TimeStamp), TimeStamp)) {
> -            CopyMem (&AuthVariable->TimeStamp, TimeStamp, sizeof (EFI_TIME));
> -          } else {
> -            CopyMem (&AuthVariable->TimeStamp,
> &(((AUTHENTICATED_VARIABLE_HEADER *)CacheVariable->CurrPtr)-
> >TimeStamp), sizeof (EFI_TIME));
> -          }
> -        }
> -      }
> -    }
> -  }
> -
> -  //
> -  // The EFI_VARIABLE_APPEND_WRITE attribute will never be set in the
> returned
> -  // Attributes bitmask parameter of a GetVariable() call.
> -  //
> -  NextVariable->Attributes = Attributes & (~EFI_VARIABLE_APPEND_WRITE);
> -
> -  VarNameOffset = GetVariableHeaderSize (AuthFormat);
> -  VarNameSize   = StrSize (VariableName);
> -  CopyMem (
> -    (UINT8 *)((UINTN)NextVariable + VarNameOffset),
> -    VariableName,
> -    VarNameSize
> -    );
> -  VarDataOffset = VarNameOffset + VarNameSize + GET_PAD_SIZE
> (VarNameSize);
> -
> -  //
> -  // If DataReady is TRUE, it means the variable data has been saved into
> -  // NextVariable during EFI_VARIABLE_APPEND_WRITE operation preparation.
> -  //
> -  if (!DataReady) {
> -    CopyMem (
> -      (UINT8 *)((UINTN)NextVariable + VarDataOffset),
> -      Data,
> -      DataSize
> -      );
> -  }
> -
> -  CopyMem (
> -    GetVendorGuidPtr (NextVariable, AuthFormat),
> -    VendorGuid,
> -    sizeof (EFI_GUID)
> -    );
> -  //
> -  // There will be pad bytes after Data, the NextVariable->NameSize and
> -  // NextVariable->DataSize should not include pad size so that variable
> -  // service can get actual size in GetVariable.
> -  //
> -  SetNameSizeOfVariable (NextVariable, VarNameSize, AuthFormat);
> -  SetDataSizeOfVariable (NextVariable, DataSize, AuthFormat);
> -
> -  //
> -  // The actual size of the variable that stores in storage should
> -  // include pad size.
> -  //
> -  VarSize = VarDataOffset + DataSize + GET_PAD_SIZE (DataSize);
> -  if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
> -    //
> -    // Create a nonvolatile variable.
> -    //
> -    Volatile = FALSE;
> -
> -    IsCommonVariable     = FALSE;
> -    IsCommonUserVariable = FALSE;
>      if ((Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) == 0) {
>        IsCommonVariable     = TRUE;
> -      IsCommonUserVariable = IsUserVariable (NextVariable);
> +      IsCommonUserVariable = IsUserVariable (NewVariable);
>      }
> +  }
> 
> -    if (  (  ((Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) != 0)
> -          && ((VarSize + mVariableModuleGlobal->HwErrVariableTotalSize) >
> PcdGet32 (PcdHwErrStorageSize)))
> -       || (IsCommonVariable && ((VarSize + mVariableModuleGlobal-
> >CommonVariableTotalSize) > mVariableModuleGlobal-
> >CommonVariableSpace))
> -       || (IsCommonVariable && AtRuntime () && ((VarSize +
> mVariableModuleGlobal->CommonVariableTotalSize) >
> mVariableModuleGlobal->CommonRuntimeVariableSpace))
> -       || (IsCommonUserVariable && ((VarSize + mVariableModuleGlobal-
> >CommonUserVariableTotalSize) > mVariableModuleGlobal-
> >CommonMaxUserVariableSpace)))
> -    {
> -      if (AtRuntime ()) {
> -        if (IsCommonUserVariable && ((VarSize + mVariableModuleGlobal-
> >CommonUserVariableTotalSize) > mVariableModuleGlobal-
> >CommonMaxUserVariableSpace)) {
> -          RecordVarErrorFlag (VAR_ERROR_FLAG_USER_ERROR, VariableName,
> VendorGuid, Attributes, VarSize);
> -        }
> -
> -        if (IsCommonVariable && ((VarSize + mVariableModuleGlobal-
> >CommonVariableTotalSize) > mVariableModuleGlobal-
> >CommonRuntimeVariableSpace)) {
> -          RecordVarErrorFlag (VAR_ERROR_FLAG_SYSTEM_ERROR, VariableName,
> VendorGuid, Attributes, VarSize);
> -        }
> -
> -        Status = EFI_OUT_OF_RESOURCES;
> -        goto Done;
> -      }
> -
> -      //
> -      // Perform garbage collection & reclaim operation, and integrate the new
> variable at the same time.
> -      //
> -      Status = Reclaim (
> -                 mVariableModuleGlobal->VariableGlobal.NonVolatileVariableBase,
> -                 &mVariableModuleGlobal->NonVolatileLastVariableOffset,
> -                 FALSE,
> -                 Variable,
> -                 NextVariable,
> -                 HEADER_ALIGN (VarSize)
> -                 );
> -      if (!EFI_ERROR (Status)) {
> -        //
> -        // The new variable has been integrated successfully during reclaiming.
> -        //
> -        if (Variable->CurrPtr != NULL) {
> -          CacheVariable->CurrPtr                = (VARIABLE_HEADER
> *)((UINTN)CacheVariable->StartPtr + ((UINTN)Variable->CurrPtr -
> (UINTN)Variable->StartPtr));
> -          CacheVariable->InDeletedTransitionPtr = NULL;
> -        }
> -
> -        UpdateVariableInfo (VariableName, VendorGuid, FALSE, FALSE, TRUE,
> FALSE, FALSE, &gVariableInfo);
> -        FlushHobVariableToFlash (VariableName, VendorGuid);
> -      } else {
> -        if (IsCommonUserVariable && ((VarSize + mVariableModuleGlobal-
> >CommonUserVariableTotalSize) > mVariableModuleGlobal-
> >CommonMaxUserVariableSpace)) {
> -          RecordVarErrorFlag (VAR_ERROR_FLAG_USER_ERROR, VariableName,
> VendorGuid, Attributes, VarSize);
> -        }
> +  //
> +  // We might need to do protection for non-volatile variable before flushing
> +  // the data to storage. A null version (meaning no protection) of following
> +  // APIs should simply return EFI_SUCCESS or EFI_UNSUPPORTED without any
> +  // changes to original data.
> +  //
> +  if (!VolatileFlag) {
> +    Status = ProtectedVariableLibUpdate (
> +               Variable->CurrPtr,
> +               Variable->InDeletedTransitionPtr,
> +               NewVariable,
> +               &VarSize
> +               );
> +    if (EFI_ERROR (Status) && (Status != EFI_UNSUPPORTED)) {
> +      return Status;
> +    }
> 
> -        if (IsCommonVariable && ((VarSize + mVariableModuleGlobal-
> >CommonVariableTotalSize) > mVariableModuleGlobal-
> >CommonVariableSpace)) {
> -          RecordVarErrorFlag (VAR_ERROR_FLAG_SYSTEM_ERROR, VariableName,
> VendorGuid, Attributes, VarSize);
> -        }
> -      }
> +    Status = EFI_SUCCESS;
> +  }
> 
> +  //
> +  // Mark the old variable as in delete transition first. There's no such need
> +  // for deleting a variable, even if variable protection is employed.
> +  //
> +  if (  !DeleteFlag
> +     && (CacheVariable->CurrPtr != NULL)
> +     && (  (CacheVariable->CurrPtr->State == VAR_ADDED)
> +        || (CacheVariable->CurrPtr->State == (VAR_ADDED &
> VAR_IN_DELETED_TRANSITION))))
> +  {
> +    Status = UpdateVariableState (
> +               Variable->CurrPtr,
> +               CacheVariable->CurrPtr,
> +               CacheVariable->CurrPtr->State & VAR_IN_DELETED_TRANSITION,
> +               Variable->Volatile
> +               );
> +    if (EFI_ERROR (Status)) {
>        goto Done;
>      }
> -
> -    if (!mVariableModuleGlobal->VariableGlobal.EmuNvMode) {
> -      //
> -      // Four steps
> -      // 1. Write variable header
> -      // 2. Set variable state to header valid
> -      // 3. Write variable data
> -      // 4. Set variable state to valid
> -      //
> -      //
> -      // Step 1:
> -      //
> -      Status = UpdateVariableStore (
> -                 &mVariableModuleGlobal->VariableGlobal,
> -                 FALSE,
> -                 TRUE,
> -                 Fvb,
> -                 mVariableModuleGlobal->NonVolatileLastVariableOffset,
> -                 (UINT32)GetVariableHeaderSize (AuthFormat),
> -                 (UINT8 *)NextVariable
> -                 );
> -
> -      if (EFI_ERROR (Status)) {
> -        goto Done;
> -      }
> -
> -      //
> -      // Step 2:
> -      //
> -      NextVariable->State = VAR_HEADER_VALID_ONLY;
> -      Status              = UpdateVariableStore (
> -                              &mVariableModuleGlobal->VariableGlobal,
> -                              FALSE,
> -                              TRUE,
> -                              Fvb,
> -                              mVariableModuleGlobal->NonVolatileLastVariableOffset +
> OFFSET_OF (VARIABLE_HEADER, State),
> -                              sizeof (UINT8),
> -                              &NextVariable->State
> -                              );
> -
> -      if (EFI_ERROR (Status)) {
> -        goto Done;
> -      }
> -
> -      //
> -      // Step 3:
> -      //
> -      Status = UpdateVariableStore (
> -                 &mVariableModuleGlobal->VariableGlobal,
> -                 FALSE,
> -                 TRUE,
> -                 Fvb,
> -                 mVariableModuleGlobal->NonVolatileLastVariableOffset +
> GetVariableHeaderSize (AuthFormat),
> -                 (UINT32)(VarSize - GetVariableHeaderSize (AuthFormat)),
> -                 (UINT8 *)NextVariable + GetVariableHeaderSize (AuthFormat)
> +  }
> +
> +  //
> +  // Have enough space to store the variable?
> +  //
> +  Status = CheckVariableStoreSpace (
> +             NewVariable,
> +             VarSize,
> +             VariableName,
> +             VendorGuid,
> +             Attributes,
> +             VolatileFlag
> +             );
> +  if (Status == EFI_OUT_OF_RESOURCES) {
> +    //
> +    // Not a chance.
> +    //
> +    goto Done;
> +  }
> +
> +  //
> +  // Maybe not...
> +  //
> +  VarStoreBase = (VolatileFlag) ? VarGlobal->VolatileVariableBase
> +                                : VarGlobal->NonVolatileVariableBase;
> +  LastVariableOffset = (VolatileFlag)
> +                        ? &mVariableModuleGlobal->VolatileLastVariableOffset
> +                        : &mVariableModuleGlobal->NonVolatileLastVariableOffset;
> +  if (!EFI_ERROR (Status)) {
> +    //
> +    // There's enough free space at the tail of variable storage.
> +    //
> +
> +    //
> +    // If non-volatile variable is protected, a separate variable
> (MetaDataHmacVar)
> +    // is always updated along with current updating variable. The buffer pointed
> +    // by NewVariable must have two variables. They should be written at this
> +    // time orderly.
> +    //
> +    NextVariable     = NewVariable;
> +    UpdatingVariable = NULL;
> +    UpdateSize       = 0;
> +    while (  !EFI_ERROR (Status)
> +          && ((UINTN)NextVariable - (UINTN)NewVariable) < VarSize)
> +    {
> +      UpdatingVariable = NextVariable;
> +      NextVariable     = GetNextVariablePtr (UpdatingVariable, VarGlobal-
> >AuthFormat);
> +      UpdateSize       = (UINTN)NextVariable - (UINTN)UpdatingVariable;
> +
> +      Status = WriteVariable (
> +                 VarStoreBase,
> +                 LastVariableOffset,
> +                 &UpdatingVariable,
> +                 (UINT32)UpdateSize,
> +                 VolatileFlag,
> +                 VarGlobal->AuthFormat
>                   );
> -
> -      if (EFI_ERROR (Status)) {
> -        goto Done;
> -      }
> -
> -      //
> -      // Step 4:
> -      //
> -      NextVariable->State = VAR_ADDED;
> -      Status              = UpdateVariableStore (
> -                              &mVariableModuleGlobal->VariableGlobal,
> -                              FALSE,
> -                              TRUE,
> -                              Fvb,
> -                              mVariableModuleGlobal->NonVolatileLastVariableOffset +
> OFFSET_OF (VARIABLE_HEADER, State),
> -                              sizeof (UINT8),
> -                              &NextVariable->State
> -                              );
> -
> -      if (EFI_ERROR (Status)) {
> -        goto Done;
> -      }
> -
> -      //
> -      // Update the memory copy of Flash region.
> -      //
> -      CopyMem ((UINT8 *)mNvVariableCache + mVariableModuleGlobal-
> >NonVolatileLastVariableOffset, (UINT8 *)NextVariable, VarSize);
> -    } else {
> -      //
> -      // Emulated non-volatile variable mode.
> -      //
> -      NextVariable->State = VAR_ADDED;
> -      Status              = UpdateVariableStore (
> -                              &mVariableModuleGlobal->VariableGlobal,
> -                              FALSE,
> -                              TRUE,
> -                              Fvb,
> -                              mVariableModuleGlobal->NonVolatileLastVariableOffset,
> -                              (UINT32)VarSize,
> -                              (UINT8 *)NextVariable
> -                              );
> -
> -      if (EFI_ERROR (Status)) {
> -        goto Done;
> -      }
>      }
> 
> -    mVariableModuleGlobal->NonVolatileLastVariableOffset += HEADER_ALIGN
> (VarSize);
> -
> +    //
> +    // UpdatingVariable must point to the last written variable. Restore it to
> +    // the first one so that we can calculate the offset in variable storage.
> +    //
> +    UpdatingVariable = (VARIABLE_HEADER *)((UINTN)UpdatingVariable +
> UpdateSize
> +                                           - VarSize);
>      if ((Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) != 0) {
> -      mVariableModuleGlobal->HwErrVariableTotalSize += HEADER_ALIGN
> (VarSize);
> +      mVariableModuleGlobal->HwErrVariableTotalSize += VarSize;
>      } else {
> -      mVariableModuleGlobal->CommonVariableTotalSize += HEADER_ALIGN
> (VarSize);
> +      mVariableModuleGlobal->CommonVariableTotalSize += VarSize;
>        if (IsCommonUserVariable) {
> -        mVariableModuleGlobal->CommonUserVariableTotalSize +=
> HEADER_ALIGN (VarSize);
> +        mVariableModuleGlobal->CommonUserVariableTotalSize += VarSize;
>        }
>      }
> -  } else {
> -    //
> -    // Create a volatile variable.
> -    //
> -    Volatile = TRUE;
> 
> -    if ((UINT32)(VarSize + mVariableModuleGlobal->VolatileLastVariableOffset) >
> -        ((VARIABLE_STORE_HEADER *)((UINTN)(mVariableModuleGlobal-
> >VariableGlobal.VolatileVariableBase)))->Size)
> -    {
> -      //
> -      // Perform garbage collection & reclaim operation, and integrate the new
> variable at the same time.
> -      //
> -      Status = Reclaim (
> -                 mVariableModuleGlobal->VariableGlobal.VolatileVariableBase,
> -                 &mVariableModuleGlobal->VolatileLastVariableOffset,
> -                 TRUE,
> +    //
> +    // Mark the old variable(s) as deleted.
> +    //
> +    if (!EFI_ERROR (Status) && (Variable->CurrPtr != NULL)) {
> +      Status = DeleteVariable (
> +                 VariableName,
> +                 VendorGuid,
>                   Variable,
> -                 NextVariable,
> -                 HEADER_ALIGN (VarSize)
> +                 CacheVariable,
> +                 VolatileFlag
>                   );
> -      if (!EFI_ERROR (Status)) {
> -        //
> -        // The new variable has been integrated successfully during reclaiming.
> -        //
> -        if (Variable->CurrPtr != NULL) {
> -          CacheVariable->CurrPtr                = (VARIABLE_HEADER
> *)((UINTN)CacheVariable->StartPtr + ((UINTN)Variable->CurrPtr -
> (UINTN)Variable->StartPtr));
> -          CacheVariable->InDeletedTransitionPtr = NULL;
> -        }
> -
> -        UpdateVariableInfo (VariableName, VendorGuid, TRUE, FALSE, TRUE,
> FALSE, FALSE, &gVariableInfo);
> -      }
> -
> -      goto Done;
>      }
> -
> -    NextVariable->State = VAR_ADDED;
> -    Status              = UpdateVariableStore (
> -                            &mVariableModuleGlobal->VariableGlobal,
> -                            TRUE,
> -                            TRUE,
> -                            Fvb,
> -                            mVariableModuleGlobal->VolatileLastVariableOffset,
> -                            (UINT32)VarSize,
> -                            (UINT8 *)NextVariable
> -                            );
> -
> -    if (EFI_ERROR (Status)) {
> -      goto Done;
> -    }
> -
> -    mVariableModuleGlobal->VolatileLastVariableOffset += HEADER_ALIGN
> (VarSize);
> -  }
> -
> -  //
> -  // Mark the old variable as deleted.
> -  //
> -  if (!EFI_ERROR (Status) && (Variable->CurrPtr != NULL)) {
> -    if (Variable->InDeletedTransitionPtr != NULL) {
> -      //
> -      // Both ADDED and IN_DELETED_TRANSITION old variable are present,
> -      // set IN_DELETED_TRANSITION one to DELETED state first.
> -      //
> -      ASSERT (CacheVariable->InDeletedTransitionPtr != NULL);
> -      State  = CacheVariable->InDeletedTransitionPtr->State;
> -      State &= VAR_DELETED;
> -      Status = UpdateVariableStore (
> -                 &mVariableModuleGlobal->VariableGlobal,
> -                 Variable->Volatile,
> -                 FALSE,
> -                 Fvb,
> -                 (UINTN)&Variable->InDeletedTransitionPtr->State,
> -                 sizeof (UINT8),
> -                 &State
> -                 );
> -      if (!EFI_ERROR (Status)) {
> -        if (!Variable->Volatile) {
> -          CacheVariable->InDeletedTransitionPtr->State = State;
> -        }
> -      } else {
> -        goto Done;
> -      }
> -    }
> -
> -    State  = CacheVariable->CurrPtr->State;
> -    State &= VAR_DELETED;
> -
> -    Status = UpdateVariableStore (
> -               &mVariableModuleGlobal->VariableGlobal,
> -               Variable->Volatile,
> -               FALSE,
> -               Fvb,
> -               (UINTN)&Variable->CurrPtr->State,
> -               sizeof (UINT8),
> -               &State
> +  } else {
> +    //
> +    // There's not enough space at the tail of variable storage but there's
> +    // enough free space holes in the whole storage. Perform garbage collection
> +    // & reclaim operation, and integrate the new variable at the same time.
> +    //
> +    Status = Reclaim (
> +               VarStoreBase,
> +               LastVariableOffset,
> +               VolatileFlag,
> +               Variable,
> +               NewVariable,
> +               VarSize
>                 );
> -    if (!EFI_ERROR (Status) && !Variable->Volatile) {
> -      CacheVariable->CurrPtr->State = State;
> -    }
> -  }
> +    UpdatingVariable = Variable->CurrPtr;
> 
> -  if (!EFI_ERROR (Status)) {
> -    UpdateVariableInfo (VariableName, VendorGuid, Volatile, FALSE, TRUE,
> FALSE, FALSE, &gVariableInfo);
> -    if (!Volatile) {
> -      FlushHobVariableToFlash (VariableName, VendorGuid);
> +    if (EFI_ERROR (Status) &&
> +        ((Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) == 0))
> +    {
> +      //
> +      // Out of space.
> +      //
> +      IsCommonUserVariable = IsUserVariable (NewVariable);
> +      IsCommonVariable     = TRUE;
> +
> +      if (IsCommonUserVariable &&
> +          ((VarSize + mVariableModuleGlobal->CommonUserVariableTotalSize)
> +           > mVariableModuleGlobal->CommonMaxUserVariableSpace))
> +      {
> +        RecordVarErrorFlag (
> +          VAR_ERROR_FLAG_USER_ERROR,
> +          VariableName,
> +          VendorGuid,
> +          Attributes,
> +          VarSize
> +          );
> +      }
> +
> +      if (IsCommonVariable &&
> +          ((VarSize + mVariableModuleGlobal->CommonVariableTotalSize)
> +           > mVariableModuleGlobal->CommonVariableSpace))
> +      {
> +        RecordVarErrorFlag (
> +          VAR_ERROR_FLAG_SYSTEM_ERROR,
> +          VariableName,
> +          VendorGuid,
> +          Attributes,
> +          VarSize
> +          );
> +      }
>      }
>    }
> 
>  Done:
>    if (!EFI_ERROR (Status)) {
> -    if (((Variable->CurrPtr != NULL) && !Variable->Volatile) || ((Attributes &
> EFI_VARIABLE_NON_VOLATILE) != 0)) {
> -      VolatileCacheInstance = &(mVariableModuleGlobal-
> >VariableGlobal.VariableRuntimeCacheContext.VariableRuntimeNvCache);
> +    if (!VolatileFlag) {
> +      Offset = (UpdatingVariable != NULL) ? (UINTN)UpdatingVariable -
> (UINTN)VarStoreBase
> +                                          : 0;
> +      Status = ProtectedVariableLibWriteFinal (
> +                 NewVariable,
> +                 VarSize,
> +                 Offset
> +                 );
> +      if (EFI_ERROR (Status) && (Status != EFI_UNSUPPORTED)) {
> +        return Status;
> +      }
> +
> +      Status = EFI_SUCCESS;
> +    }
> +
> +    UpdateVariableInfo (
> +      VariableName,
> +      VendorGuid,
> +      VolatileFlag,
> +      FALSE,
> +      TRUE,
> +      FALSE,
> +      FALSE,
> +      &gVariableInfo
> +      );
> +    //
> +    // HOB copy of the same variable is no longer needed, no matter it has
> +    // been deleted, updated or added from/to real variable storage.
> +    //
> +    if (HobVarOnlyFlag || !VolatileFlag) {
> +      FlushHobVariableToFlash (VariableName, VendorGuid);
> +    }
> +
> +    if (!VolatileFlag) {
> +      VolatileCacheInstance = &(VarGlobal-
> >VariableRuntimeCacheContext.VariableRuntimeNvCache);
>      } else {
> -      VolatileCacheInstance = &(mVariableModuleGlobal-
> >VariableGlobal.VariableRuntimeCacheContext.VariableRuntimeVolatileCache);
> +      VolatileCacheInstance = &(VarGlobal-
> >VariableRuntimeCacheContext.VariableRuntimeVolatileCache);
>      }
> 
>      if (VolatileCacheInstance->Store != NULL) {
> @@ -2401,6 +2525,11 @@ Done:
>                    );
>        ASSERT_EFI_ERROR (Status);
>      }
> +  } else if (Status == EFI_ALREADY_STARTED) {
> +    //
> +    // Meaning nothing needs to be done. Just return success.
> +    //
> +    Status = EFI_SUCCESS;
>    }
> 
>    return Status;
> @@ -2440,7 +2569,6 @@ VariableServiceGetVariable (
>  {
>    EFI_STATUS              Status;
>    VARIABLE_POINTER_TRACK  Variable;
> -  UINTN                   VarDataSize;
> 
>    if ((VariableName == NULL) || (VendorGuid == NULL) || (DataSize == NULL)) {
>      return EFI_INVALID_PARAMETER;
> @@ -2458,28 +2586,26 @@ VariableServiceGetVariable (
>    }
> 
>    //
> -  // Get data size
> +  // Get data and its size
>    //
> -  VarDataSize = DataSizeOfVariable (Variable.CurrPtr, mVariableModuleGlobal-
> >VariableGlobal.AuthFormat);
> -  ASSERT (VarDataSize != 0);
> +  if (!Variable.Volatile) {
> +    //
> +    // Currently only non-volatile variable needs protection.
> +    //
> +    Status = ProtectedVariableLibGetByBuffer (
> +               Variable.CurrPtr,
> +               Data,
> +               (UINT32 *)DataSize,
> +               mVariableModuleGlobal->VariableGlobal.AuthFormat
> +               );
> +  }
> 
> -  if (*DataSize >= VarDataSize) {
> -    if (Data == NULL) {
> -      Status = EFI_INVALID_PARAMETER;
> -      goto Done;
> -    }
> +  if (Variable.Volatile || (Status == EFI_UNSUPPORTED)) {
> +    Status = GetVariableData (Variable.CurrPtr, Data, (UINT32 *)DataSize,
> mVariableModuleGlobal->VariableGlobal.AuthFormat);
> +  }
> 
> -    CopyMem (Data, GetVariableDataPtr (Variable.CurrPtr,
> mVariableModuleGlobal->VariableGlobal.AuthFormat), VarDataSize);
> -
> -    *DataSize = VarDataSize;
> +  if (!EFI_ERROR (Status)) {
>      UpdateVariableInfo (VariableName, VendorGuid, Variable.Volatile, TRUE,
> FALSE, FALSE, FALSE, &gVariableInfo);
> -
> -    Status = EFI_SUCCESS;
> -    goto Done;
> -  } else {
> -    *DataSize = VarDataSize;
> -    Status    = EFI_BUFFER_TOO_SMALL;
> -    goto Done;
>    }
> 
>  Done:
> @@ -2860,7 +2986,7 @@ VariableServiceSetVariable (
>      // Parse non-volatile variable data and get last variable offset.
>      //
>      NextVariable = GetStartPointer ((VARIABLE_STORE_HEADER *)(UINTN)Point);
> -    while (IsValidVariableHeader (NextVariable, GetEndPointer
> ((VARIABLE_STORE_HEADER *)(UINTN)Point))) {
> +    while (IsValidVariableHeader (NextVariable, GetEndPointer
> ((VARIABLE_STORE_HEADER *)(UINTN)Point), AuthFormat)) {
>        NextVariable = GetNextVariablePtr (NextVariable, AuthFormat);
>      }
> 
> @@ -3022,7 +3148,12 @@ VariableServiceQueryVariableInfoInternal (
>    //
>    // Now walk through the related variable store.
>    //
> -  while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader)))
> {
> +  while (IsValidVariableHeader (
> +           Variable,
> +           GetEndPointer (VariableStoreHeader),
> +           mVariableModuleGlobal->VariableGlobal.AuthFormat
> +           ))
> +  {
>      NextVariable = GetNextVariablePtr (Variable, mVariableModuleGlobal-
> >VariableGlobal.AuthFormat);
>      VariableSize = (UINT64)(UINTN)NextVariable - (UINT64)(UINTN)Variable;
> 
> @@ -3315,7 +3446,7 @@ FlushHobVariableToFlash (
>      //
>      mVariableModuleGlobal->VariableGlobal.HobVariableBase = 0;
>      for ( Variable = GetStartPointer (VariableStoreHeader)
> -          ; IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader))
> +          ; IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader),
> AuthFormat)
>            ; Variable = GetNextVariablePtr (Variable, AuthFormat)
>            )
>      {
> @@ -3525,11 +3656,11 @@ ConvertNormalVarStorageToAuthVarStorage (
>    VARIABLE_HEADER                *StartPtr;
>    UINT8                          *NextPtr;
>    VARIABLE_HEADER                *EndPtr;
> -  UINTN                          AuthVarStroageSize;
> +  UINTN                          AuthVarStorageSize;
>    AUTHENTICATED_VARIABLE_HEADER  *AuthStartPtr;
>    VARIABLE_STORE_HEADER          *AuthVarStorage;
> 
> -  AuthVarStroageSize = sizeof (VARIABLE_STORE_HEADER);
> +  AuthVarStorageSize = sizeof (VARIABLE_STORE_HEADER);
>    //
>    // Set AuthFormat as FALSE for normal variable storage
>    //
> @@ -3542,10 +3673,10 @@ ConvertNormalVarStorageToAuthVarStorage (
>    EndPtr   = GetEndPointer (NormalVarStorage);
>    while (StartPtr < EndPtr) {
>      if (StartPtr->State == VAR_ADDED) {
> -      AuthVarStroageSize  = HEADER_ALIGN (AuthVarStroageSize);
> -      AuthVarStroageSize += sizeof (AUTHENTICATED_VARIABLE_HEADER);
> -      AuthVarStroageSize += StartPtr->NameSize + GET_PAD_SIZE (StartPtr-
> >NameSize);
> -      AuthVarStroageSize += StartPtr->DataSize + GET_PAD_SIZE (StartPtr-
> >DataSize);
> +      AuthVarStorageSize  = HEADER_ALIGN (AuthVarStorageSize);
> +      AuthVarStorageSize += sizeof (AUTHENTICATED_VARIABLE_HEADER);
> +      AuthVarStorageSize += StartPtr->NameSize + GET_PAD_SIZE (StartPtr-
> >NameSize);
> +      AuthVarStorageSize += StartPtr->DataSize + GET_PAD_SIZE (StartPtr-
> >DataSize);
>      }
> 
>      StartPtr = GetNextVariablePtr (StartPtr, mVariableModuleGlobal-
> >VariableGlobal.AuthFormat);
> @@ -3554,7 +3685,7 @@ ConvertNormalVarStorageToAuthVarStorage (
>    //
>    // Allocate Runtime memory for Auth Variable Storage
>    //
> -  AuthVarStorage = AllocateRuntimeZeroPool (AuthVarStroageSize);
> +  AuthVarStorage = AllocateRuntimeZeroPool (AuthVarStorageSize);
>    ASSERT (AuthVarStorage != NULL);
>    if (AuthVarStorage == NULL) {
>      return NULL;
> @@ -3608,7 +3739,7 @@ ConvertNormalVarStorageToAuthVarStorage (
>    AuthVarStorage->State  = NormalVarStorage->State;
>    AuthVarStorage->Size   = (UINT32)((UINTN)AuthStartPtr -
> (UINTN)AuthVarStorage);
>    CopyGuid (&AuthVarStorage->Signature, &gEfiAuthenticatedVariableGuid);
> -  ASSERT (AuthVarStorage->Size <= AuthVarStroageSize);
> +  ASSERT (AuthVarStorage->Size <= AuthVarStorageSize);
> 
>    //
>    // Restore AuthFormat
> @@ -3774,7 +3905,7 @@ VariableCommonInitialize (
>    //
>    // Allocate memory for volatile variable store, note that there is a scratch
> space to store scratch data.
>    //
> -  ScratchSize                              = GetMaxVariableSize ();
> +  ScratchSize                              = GetMaxVariableSize () * 2;
>    mVariableModuleGlobal->ScratchBufferSize = ScratchSize;
>    VolatileVariableStore                    = AllocateRuntimePool (PcdGet32
> (PcdVariableStoreSize) + ScratchSize);
>    if (VolatileVariableStore == NULL) {
> diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableDxe.c
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableDxe.c
> index 03fec3048dc4..52bf29ec4c5c 100644
> --- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableDxe.c
> +++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableDxe.c
> @@ -3,7 +3,7 @@
>    and volatile storage space and install variable architecture protocol.
> 
>  Copyright (C) 2013, Red Hat, Inc.
> -Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
>  (C) Copyright 2015 Hewlett Packard Enterprise Development LP<BR>
>  Copyright (c) Microsoft Corporation.
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> @@ -14,6 +14,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  #include <Protocol/VariablePolicy.h>
>  #include <Library/VariablePolicyLib.h>
> +#include "VariableParsing.h"
> 
>  EFI_STATUS
>  EFIAPI
> @@ -534,6 +535,29 @@ VariableServiceInitialize (
>    EFI_EVENT   ReadyToBootEvent;
>    EFI_EVENT   EndOfDxeEvent;
> 
> +  PROTECTED_VARIABLE_CONTEXT_IN  ContextIn;
> +
> +  //
> +  // Initialze protected variable service, if enabled.
> +  //
> +  ContextIn.StructSize    = sizeof (ContextIn);
> +  ContextIn.StructVersion =
> PROTECTED_VARIABLE_CONTEXT_IN_STRUCT_VERSION;
> +
> +  ContextIn.FindVariableSmm     = NULL;
> +  ContextIn.GetVariableInfo     = GetVariableInfo;
> +  ContextIn.GetNextVariableInfo = GetNextVariableInfo;
> +  ContextIn.UpdateVariableStore = VariableExLibUpdateNvVariable;
> +  ContextIn.UpdateVariable      = VariableExLibUpdateVariable;
> +
> +  ContextIn.MaxVariableSize     = (UINT32)GetMaxVariableSize ();
> +  ContextIn.VariableServiceUser = FromSmmModule;
> +
> +  Status = ProtectedVariableLibInitialize (&ContextIn);
> +  if (EFI_ERROR (Status) && (Status != EFI_UNSUPPORTED)) {
> +    ASSERT_EFI_ERROR (Status);
> +    return Status;
> +  }
> +
>    Status = VariableCommonInitialize ();
>    ASSERT_EFI_ERROR (Status);
> 
> diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableExLib.c
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableExLib.c
> index 62cde0335512..5904bcbff78a 100644
> --- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableExLib.c
> +++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableExLib.c
> @@ -1,13 +1,14 @@
>  /** @file
>    Provides variable driver extended services.
> 
> -Copyright (c) 2015 - 2019, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2015 - 2022, Intel Corporation. All rights reserved.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> 
>  #include "Variable.h"
>  #include "VariableParsing.h"
> +#include "VariableRuntimeCache.h"
> 
>  /**
>    Finds variable in storage blocks of volatile and non-volatile storage areas.
> @@ -38,6 +39,7 @@ VariableExLibFindVariable (
>    EFI_STATUS                     Status;
>    VARIABLE_POINTER_TRACK         Variable;
>    AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
> +  PROTECTED_VARIABLE_INFO        VarInfo;
> 
>    Status = FindVariable (
>               VariableName,
> @@ -56,9 +58,12 @@ VariableExLibFindVariable (
>      return Status;
>    }
> 
> -  AuthVariableInfo->DataSize   = DataSizeOfVariable (Variable.CurrPtr,
> mVariableModuleGlobal->VariableGlobal.AuthFormat);
> -  AuthVariableInfo->Data       = GetVariableDataPtr (Variable.CurrPtr,
> mVariableModuleGlobal->VariableGlobal.AuthFormat);
> -  AuthVariableInfo->Attributes = Variable.CurrPtr->Attributes;
> +  AuthVariableInfo->NameSize     = NameSizeOfVariable (Variable.CurrPtr,
> mVariableModuleGlobal->VariableGlobal.AuthFormat);
> +  AuthVariableInfo->VariableName = GetVariableNamePtr (Variable.CurrPtr,
> mVariableModuleGlobal->VariableGlobal.AuthFormat);
> +  AuthVariableInfo->VendorGuid   = GetVendorGuidPtr (Variable.CurrPtr,
> mVariableModuleGlobal->VariableGlobal.AuthFormat);
> +  AuthVariableInfo->DataSize     = DataSizeOfVariable (Variable.CurrPtr,
> mVariableModuleGlobal->VariableGlobal.AuthFormat);
> +  AuthVariableInfo->Data         = GetVariableDataPtr (Variable.CurrPtr,
> mVariableModuleGlobal->VariableGlobal.AuthFormat);
> +  AuthVariableInfo->Attributes   = Variable.CurrPtr->Attributes;
>    if (mVariableModuleGlobal->VariableGlobal.AuthFormat) {
>      AuthVariable                     = (AUTHENTICATED_VARIABLE_HEADER
> *)Variable.CurrPtr;
>      AuthVariableInfo->PubKeyIndex    = AuthVariable->PubKeyIndex;
> @@ -66,6 +71,24 @@ VariableExLibFindVariable (
>      AuthVariableInfo->TimeStamp      = &AuthVariable->TimeStamp;
>    }
> 
> +  CopyMem (&VarInfo.Header, AuthVariableInfo, sizeof (VarInfo.Header));
> +
> +  VarInfo.Buffer        = Variable.CurrPtr;
> +  VarInfo.PlainData     = NULL;
> +  VarInfo.PlainDataSize = 0;
> +  VarInfo.Flags.Auth    = mVariableModuleGlobal->VariableGlobal.AuthFormat;
> +
> +  //
> +  // In case the variable is encrypted.
> +  //
> +  Status = ProtectedVariableLibGetByInfo (&VarInfo);
> +  if (!EFI_ERROR (Status)) {
> +    if (VarInfo.PlainData != NULL) {
> +      AuthVariableInfo->Data     = VarInfo.PlainData;
> +      AuthVariableInfo->DataSize = VarInfo.PlainDataSize;
> +    }
> +  }
> +
>    return EFI_SUCCESS;
>  }
> 
> @@ -99,6 +122,7 @@ VariableExLibFindNextVariable (
>    VARIABLE_HEADER                *VariablePtr;
>    AUTHENTICATED_VARIABLE_HEADER  *AuthVariablePtr;
>    VARIABLE_STORE_HEADER
> *VariableStoreHeader[VariableStoreTypeMax];
> +  PROTECTED_VARIABLE_INFO        VarInfo;
> 
>    VariableStoreHeader[VariableStoreTypeVolatile] = (VARIABLE_STORE_HEADER
> *)(UINTN)mVariableModuleGlobal->VariableGlobal.VolatileVariableBase;
>    VariableStoreHeader[VariableStoreTypeHob]      = (VARIABLE_STORE_HEADER
> *)(UINTN)mVariableModuleGlobal->VariableGlobal.HobVariableBase;
> @@ -123,6 +147,7 @@ VariableExLibFindNextVariable (
>      return Status;
>    }
> 
> +  AuthVariableInfo->NameSize     = NameSizeOfVariable (VariablePtr,
> mVariableModuleGlobal->VariableGlobal.AuthFormat);
>    AuthVariableInfo->VariableName = GetVariableNamePtr (VariablePtr,
> mVariableModuleGlobal->VariableGlobal.AuthFormat);
>    AuthVariableInfo->VendorGuid   = GetVendorGuidPtr (VariablePtr,
> mVariableModuleGlobal->VariableGlobal.AuthFormat);
>    AuthVariableInfo->DataSize     = DataSizeOfVariable (VariablePtr,
> mVariableModuleGlobal->VariableGlobal.AuthFormat);
> @@ -135,6 +160,20 @@ VariableExLibFindNextVariable (
>      AuthVariableInfo->TimeStamp      = &AuthVariablePtr->TimeStamp;
>    }
> 
> +  CopyMem (&VarInfo.Header, AuthVariableInfo, sizeof (VarInfo.Header));
> +
> +  VarInfo.Buffer        = VariablePtr;
> +  VarInfo.PlainData     = NULL;
> +  VarInfo.PlainDataSize = 0;
> +
> +  Status = ProtectedVariableLibGetByInfo (&VarInfo);
> +  if (!EFI_ERROR (Status)) {
> +    if (VarInfo.PlainData != NULL) {
> +      AuthVariableInfo->Data     = VarInfo.PlainData;
> +      AuthVariableInfo->DataSize = VarInfo.PlainDataSize;
> +    }
> +  }
> +
>    return EFI_SUCCESS;
>  }
> 
> @@ -256,3 +295,123 @@ VariableExLibAtRuntime (
>  {
>    return AtRuntime ();
>  }
> +
> +/**
> +  Update partial data of a variable on NV storage and/or cached copy.
> +
> +  @param[in]  VariableInfo  Pointer to a variable with detailed information.
> +  @param[in]  Offset        Offset to write from.
> +  @param[in]  Size          Size of data Buffer to update.
> +  @param[in]  Buffer        Pointer to data buffer to update.
> +
> +  @retval EFI_SUCCESS             The variable data was updated successfully.
> +  @retval EFI_UNSUPPORTED         If this function is called directly in runtime.
> +  @retval EFI_INVALID_PARAMETER   If VariableInfo, Buffer or Size are not
> valid.
> +  @retval Others                  Failed to update NV storage or variable cache.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +VariableExLibUpdateNvVariable (
> +  IN  PROTECTED_VARIABLE_INFO  *VariableInfo,
> +  IN  UINTN                    Offset,
> +  IN  UINT32                   Size,
> +  IN  UINT8                    *Buffer
> +  )
> +{
> +  EFI_STATUS              Status;
> +  VARIABLE_GLOBAL         *Global;
> +  VARIABLE_RUNTIME_CACHE  *CacheInstance;
> +  VARIABLE_HEADER         *VariableCache;
> +
> +  if ((mVariableModuleGlobal == NULL) || (mNvVariableCache == NULL)) {
> +    return EFI_UNSUPPORTED;
> +  }
> +
> +  //
> +  // Flush the cache to store.
> +  //
> +  if (Size == (UINT32)-1) {
> +    Status = FtwVariableSpace (
> +               mVariableModuleGlobal->VariableGlobal.NonVolatileVariableBase,
> +               mNvVariableCache
> +               );
> +    if (  !EFI_ERROR (Status)
> +       && (mVariableModuleGlobal->VariableGlobal.HobVariableBase != 0))
> +    {
> +      FlushHobVariableToFlash (NULL, NULL);
> +      if (mVariableModuleGlobal->VariableGlobal.HobVariableBase != 0) {
> +        FreePool ((VOID *)(UINTN)mVariableModuleGlobal-
> >VariableGlobal.HobVariableBase);
> +        mVariableModuleGlobal->VariableGlobal.HobVariableBase = 0;
> +      }
> +    }
> +
> +    return Status;
> +  }
> +
> +  if (  (VariableInfo == NULL)
> +     || (VariableInfo->StoreIndex == VAR_INDEX_INVALID)
> +     || (Buffer == NULL)
> +     || (Size == 0))
> +  {
> +    ASSERT (VariableInfo != NULL);
> +    ASSERT (VariableInfo->StoreIndex != VAR_INDEX_INVALID);
> +    ASSERT (Buffer != NULL);
> +    ASSERT (Size != 0);
> +    return EFI_INVALID_PARAMETER;
> +  }
> +
> +  Global = &mVariableModuleGlobal->VariableGlobal;
> +
> +  VariableCache = (VARIABLE_HEADER *)((UINTN)mNvVariableCache +
> (UINTN)VariableInfo->StoreIndex);
> +
> +  ASSERT (
> +    StrCmp (
> +      VariableInfo->Header.VariableName,
> +      GetVariableNamePtr (VariableCache, Global->AuthFormat)
> +      ) == 0
> +    );
> +  ASSERT (
> +    CompareGuid (
> +      VariableInfo->Header.VendorGuid,
> +      GetVendorGuidPtr (VariableCache, Global->AuthFormat)
> +      )
> +    );
> +
> +  //
> +  // Forcibly update part data of flash copy of the variable ...
> +  //
> +  Status =  UpdateVariableStore (
> +              Global,
> +              FALSE,
> +              FALSE,
> +              mVariableModuleGlobal->FvbInstance,
> +              (UINTN)(Global->NonVolatileVariableBase + VariableInfo->StoreIndex +
> Offset),
> +              Size,
> +              Buffer
> +              );
> +  if (EFI_ERROR (Status)) {
> +    ASSERT_EFI_ERROR (Status);
> +    return Status;
> +  }
> +
> +  //
> +  // ... as well as the local cached copy.
> +  //
> +  CopyMem ((VOID *)((UINTN)VariableCache + Offset), Buffer, Size);
> +
> +  //
> +  // Sync remote cached copy.
> +  //
> +  CacheInstance = &Global-
> >VariableRuntimeCacheContext.VariableRuntimeNvCache;
> +  if (CacheInstance->Store != NULL) {
> +    Status =  SynchronizeRuntimeVariableCache (
> +                CacheInstance,
> +                (UINTN)VariableInfo->StoreIndex + Offset,
> +                Size
> +                );
> +    ASSERT_EFI_ERROR (Status);
> +  }
> +
> +  return EFI_SUCCESS;
> +}
> diff --git
> a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableNonVolatile.c
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableNonVolatile.c
> index 5e9d40b67ac2..e8b8f0b7f705 100644
> --- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableNonVolatile.c
> +++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableNonVolatile.c
> @@ -1,7 +1,7 @@
>  /** @file
>    Common variable non-volatile store routines.
> 
> -Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2019 - 2022, Intel Corporation. All rights reserved.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> @@ -120,6 +120,181 @@ InitEmuNonVolatileVariableStore (
>    return EFI_SUCCESS;
>  }
> 
> +/**
> +
> +  Create a dummy variable used to fill the gap in NV variable storage caused by
> +  the invalid variables found in HMAC verification phase.
> +
> +  @param[out] Variable    Variable buffer.
> +  @param[in]  Name        Variable Name.
> +  @param[in]  Guid        Vendor GUID of the variable.
> +  @param[in]  Size        Whole size of the variable requested.
> +  @param[in]  AuthFlag    Variable format flag.
> +
> +**/
> +STATIC
> +VOID
> +CreateDummyVariable (
> +  OUT VARIABLE_HEADER  *Variable,
> +  IN  CHAR16           *Name,
> +  IN  EFI_GUID         *Guid,
> +  IN  UINT32           Size,
> +  IN  BOOLEAN          AuthFlag
> +  )
> +{
> +  AUTHENTICATED_VARIABLE_HEADER  *AuthVariable;
> +
> +  ASSERT (Variable != NULL);
> +
> +  if (Name == NULL) {
> +    Name = L"Dummy";
> +  }
> +
> +  if (AuthFlag) {
> +    AuthVariable = (AUTHENTICATED_VARIABLE_HEADER *)Variable;
> +
> +    AuthVariable->StartId    = VARIABLE_DATA;
> +    AuthVariable->State      = VAR_ADDED & VAR_DELETED;
> +    AuthVariable->Attributes = EFI_VARIABLE_NON_VOLATILE;
> +    AuthVariable->NameSize   = (UINT32)StrSize (Name);
> +    AuthVariable->DataSize   = Size - sizeof
> (AUTHENTICATED_VARIABLE_HEADER)
> +                               - AuthVariable->NameSize;
> +    if (Guid != NULL) {
> +      CopyMem ((VOID *)&AuthVariable->VendorGuid, (VOID *)Guid, sizeof
> (EFI_GUID));
> +    }
> +
> +    CopyMem (GetVariableNamePtr (Variable, AuthFlag), (VOID *)Name,
> AuthVariable->NameSize);
> +  } else {
> +    Variable->StartId    = VARIABLE_DATA;
> +    Variable->State      = VAR_ADDED & VAR_DELETED;
> +    Variable->Attributes = EFI_VARIABLE_NON_VOLATILE;
> +    Variable->NameSize   = (UINT32)StrSize (Name);
> +    Variable->DataSize   = Size - sizeof (VARIABLE_HEADER) - Variable-
> >NameSize;
> +    if (Guid != NULL) {
> +      CopyMem ((VOID *)&Variable->VendorGuid, (VOID *)Guid, sizeof
> (EFI_GUID));
> +    }
> +
> +    CopyMem (GetVariableNamePtr (Variable, AuthFlag), (VOID *)Name,
> Variable->NameSize);
> +  }
> +}
> +
> +/**
> +
> +  Init protected variable store.
> +
> +  @param[in, out]  VariableStore  Pointer to real protected variable store base.
> +
> +**/
> +EFI_STATUS
> +InitProtectedVariableStore (
> +  IN  OUT VARIABLE_STORE_HEADER  *VariableStore
> +  )
> +{
> +  EFI_STATUS               Status;
> +  PROTECTED_VARIABLE_INFO  VarInfo;
> +  UINTN                    Size;
> +  UINTN                    Index;
> +  BOOLEAN                  AuthFlag;
> +  EFI_PHYSICAL_ADDRESS     NextVariableStore;
> +  EFI_PHYSICAL_ADDRESS     *VarList;
> +  UINTN                    NumVars;
> +  UINTN                    CurrVar;
> +
> +  SetMem (
> +    (UINT8 *)VariableStore + sizeof (VARIABLE_STORE_HEADER),
> +    VariableStore->Size - sizeof (VARIABLE_STORE_HEADER),
> +    0xFF
> +    );
> +  Index = sizeof (VARIABLE_STORE_HEADER);
> +
> +  VarList = NULL;
> +  NumVars = 0;
> +  ProtectedVariableLibGetSortedList (&VarList, &NumVars);
> +
> +  //
> +  // Search variable in the order of StoreIndex
> +  //
> +  ZeroMem (&VarInfo, sizeof (VarInfo));
> +
> +  for (CurrVar = 0; CurrVar < NumVars; CurrVar++) {
> +    VarInfo.Buffer     = NULL;
> +    VarInfo.StoreIndex = VarList[CurrVar];
> +    if (VarInfo.StoreIndex == VAR_INDEX_INVALID) {
> +      break;
> +    }
> +
> +    Status = ProtectedVariableLibFind (&VarInfo);
> +    if (EFI_ERROR (Status)) {
> +      break;
> +    }
> +
> +    ASSERT (VarInfo.Buffer != NULL);
> +
> +    AuthFlag = VarInfo.Flags.Auth;
> +    if (VarInfo.StoreIndex == VAR_INDEX_INVALID) {
> +      continue;
> +    } else {
> +      ASSERT (VarInfo.StoreIndex == HEADER_ALIGN (VarInfo.StoreIndex));
> +      ASSERT (VarInfo.StoreIndex < (VariableStore->Size - sizeof
> (VARIABLE_STORE_HEADER)));
> +      ASSERT ((VariableStore->Size - VarInfo.StoreIndex) > GetVariableHeaderSize
> (AuthFlag));
> +    }
> +
> +    //
> +    // Fill gap caused by invalid variable.
> +    //
> +    if (VarInfo.StoreIndex > Index) {
> +      Size = (UINTN)VarInfo.StoreIndex - Index;
> +      CreateDummyVariable (
> +        (VARIABLE_HEADER *)((UINT8 *)VariableStore + Index),
> +        NULL,
> +        NULL,
> +        (UINT32)Size,
> +        AuthFlag
> +        );
> +      Index += Size;
> +    }
> +
> +    Size = (UINTN)GetNextVariablePtr (VarInfo.Buffer, AuthFlag)
> +           - (UINTN)VarInfo.Buffer;
> +    CopyMem ((UINT8 *)VariableStore + VarInfo.StoreIndex, VarInfo.Buffer,
> Size);
> +
> +    Index += Size;
> +    Index  = HEADER_ALIGN (Index);
> +
> +    NextVariableStore = (EFI_PHYSICAL_ADDRESS)((UINTN)VariableStore +
> VarInfo.StoreIndex + Size);
> +  }
> +
> +  //
> +  // Search variable in the order of StoreIndex
> +  //
> +  ZeroMem (&VarInfo, sizeof (VarInfo));
> +  for ( ; CurrVar < NumVars; CurrVar++) {
> +    VarInfo.Buffer     = NULL;
> +    VarInfo.StoreIndex = VarList[CurrVar];
> +    Status             = ProtectedVariableLibFind (&VarInfo);
> +    if (EFI_ERROR (Status)) {
> +      break;
> +    }
> +
> +    ASSERT (VarInfo.Buffer != NULL);
> +
> +    AuthFlag = VarInfo.Flags.Auth;
> +    if (VarInfo.StoreIndex == VAR_INDEX_INVALID) {
> +      Size = (UINTN)GetNextVariablePtr (VarInfo.Buffer, AuthFlag)
> +             - (UINTN)VarInfo.Buffer;
> +      CopyMem ((UINT8 *)&NextVariableStore, VarInfo.Buffer, Size);
> +      Status            = ProtectedVariableLibRefresh (VarInfo.Buffer, 0,
> NextVariableStore - (UINTN)VariableStore, FALSE);
> +      NextVariableStore = NextVariableStore + Size;
> +    }
> +  }
> +
> +  if (Status == EFI_UNSUPPORTED) {
> +    return Status;
> +  }
> +
> +  return EFI_SUCCESS;
> +}
> +
>  /**
>    Init real non-volatile variable store.
> 
> @@ -230,6 +405,16 @@ InitRealNonVolatileVariableStore (
>      return EFI_VOLUME_CORRUPTED;
>    }
> 
> +  //
> +  // Overwrite the store with verified copy of protected variables, if enabled.
> +  //
> +  Status = InitProtectedVariableStore (VariableStore);
> +  if ((Status != EFI_SUCCESS) && (Status != EFI_UNSUPPORTED)) {
> +    FreePool (NvStorageData);
> +    DEBUG ((DEBUG_ERROR, "Variable integrity might have been
> compromised\n"));
> +    return Status;
> +  }
> +
>    mNvFvHeaderCache = FvHeader;
> 
>    *VariableStoreBase = (EFI_PHYSICAL_ADDRESS)(UINTN)VariableStore;
> @@ -323,7 +508,12 @@ InitNonVolatileVariableStore (
>    // Parse non-volatile variable data and get last variable offset.
>    //
>    Variable = GetStartPointer (mNvVariableCache);
> -  while (IsValidVariableHeader (Variable, GetEndPointer (mNvVariableCache))) {
> +  while (IsValidVariableHeader (
> +           Variable,
> +           GetEndPointer (mNvVariableCache),
> +           mVariableModuleGlobal->VariableGlobal.AuthFormat
> +           ))
> +  {
>      NextVariable = GetNextVariablePtr (Variable, mVariableModuleGlobal-
> >VariableGlobal.AuthFormat);
>      VariableSize = (UINTN)NextVariable - (UINTN)Variable;
>      if ((Variable->Attributes & (EFI_VARIABLE_NON_VOLATILE |
> EFI_VARIABLE_HARDWARE_ERROR_RECORD)) ==
> (EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_HARDWARE_ERROR_RECORD))
> {
> diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.c
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.c
> index 39060ed405b8..000e4b546888 100644
> --- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.c
> +++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.c
> @@ -2,11 +2,12 @@
>    Functions in this module are associated with variable parsing operations and
>    are intended to be usable across variable driver source files.
> 
> -Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2019 - 2022, Intel Corporation. All rights reserved.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> 
> +#include "Variable.h"
>  #include "VariableParsing.h"
> 
>  /**
> @@ -15,6 +16,8 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>    @param[in] Variable           Pointer to the Variable Header.
>    @param[in] VariableStoreEnd   Pointer to the Variable Store End.
> +  @param[in] AuthFormat         TRUE indicates authenticated variables are used.
> +                                FALSE indicates authenticated variables are not used.
> 
>    @retval TRUE              Variable header is valid.
>    @retval FALSE             Variable header is not valid.
> @@ -23,10 +26,14 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
>  BOOLEAN
>  IsValidVariableHeader (
>    IN  VARIABLE_HEADER  *Variable,
> -  IN  VARIABLE_HEADER  *VariableStoreEnd
> +  IN  VARIABLE_HEADER  *VariableStoreEnd,
> +  IN  BOOLEAN          AuthFormat
>    )
>  {
> -  if ((Variable == NULL) || (Variable >= VariableStoreEnd) || (Variable->StartId !=
> VARIABLE_DATA)) {
> +  if (  (Variable == NULL)
> +     || (((UINTN)Variable + GetVariableHeaderSize (AuthFormat)) >=
> (UINTN)VariableStoreEnd)
> +     || (Variable->StartId != VARIABLE_DATA))
> +  {
>      //
>      // Variable is NULL or has reached the end of variable store,
>      // or the StartId is not correct.
> @@ -341,6 +348,52 @@ GetVariableDataOffset (
>    return Value;
>  }
> 
> +/**
> +  Get variable data payload.
> +
> +  @param[in]      Variable     Pointer to the Variable Header.
> +  @param[in,out]  Data         Pointer to buffer used to store the variable data.
> +  @param[in,out]  DataSize     Size of buffer passed by Data.
> +                               Size of data copied into Data buffer.
> +  @param[in]      AuthFlag     Auth-variable indicator.
> +
> +  @return EFI_SUCCESS             Data was fetched.
> +  @return EFI_INVALID_PARAMETER   DataSize is NULL.
> +  @return EFI_BUFFER_TOO_SMALL    DataSize is smaller than size of variable
> data.
> +
> +**/
> +EFI_STATUS
> +GetVariableData (
> +  IN      VARIABLE_HEADER  *Variable,
> +  IN  OUT VOID             *Data,
> +  IN  OUT UINT32           *DataSize,
> +  IN      BOOLEAN          AuthFlag
> +  )
> +{
> +  UINT32  Size;
> +
> +  if (DataSize == NULL) {
> +    ASSERT (DataSize != NULL);
> +    return EFI_INVALID_PARAMETER;
> +  }
> +
> +  Size = (UINT32)DataSizeOfVariable (Variable, AuthFlag);
> +  if (*DataSize < Size) {
> +    *DataSize = Size;
> +    return EFI_BUFFER_TOO_SMALL;
> +  }
> +
> +  if (Data == NULL) {
> +    ASSERT (Data != NULL);
> +    return EFI_INVALID_PARAMETER;
> +  }
> +
> +  CopyMem (Data, GetVariableDataPtr (Variable, AuthFlag), Size);
> +  *DataSize = Size;
> +
> +  return EFI_SUCCESS;
> +}
> +
>  /**
> 
>    This code gets the pointer to the next variable header.
> @@ -479,7 +532,7 @@ FindVariableEx (
>    InDeletedVariable = NULL;
> 
>    for ( PtrTrack->CurrPtr = PtrTrack->StartPtr
> -        ; IsValidVariableHeader (PtrTrack->CurrPtr, PtrTrack->EndPtr)
> +        ; IsValidVariableHeader (PtrTrack->CurrPtr, PtrTrack->EndPtr, AuthFormat)
>          ; PtrTrack->CurrPtr = GetNextVariablePtr (PtrTrack->CurrPtr, AuthFormat)
>          )
>    {
> @@ -608,7 +661,7 @@ VariableServiceGetNextVariableInternal (
>      //
>      // Switch to the next variable store if needed
>      //
> -    while (!IsValidVariableHeader (Variable.CurrPtr, Variable.EndPtr)) {
> +    while (!IsValidVariableHeader (Variable.CurrPtr, Variable.EndPtr,
> AuthFormat)) {
>        //
>        // Find current storage index
>        //
> @@ -804,3 +857,260 @@ UpdateVariableInfo (
>      }
>    }
>  }
> +
> +/**
> +
> +  Retrieve details about a variable and return them in VariableInfo->Header.
> +
> +  If VariableInfo->Address is given, this function will calculate its offset
> +  relative to given variable storage via VariableStore; Otherwise, it will try
> +  other internal variable storages or cached copies. It's assumed that, for all
> +  copies of NV variable storage, all variables are stored in the same relative
> +  position. If VariableInfo->Address is found in the range of any storage copies,
> +  its offset relative to that storage should be the same in other copies.
> +
> +  If VariableInfo->Offset is given (non-zero) but not VariableInfo->Address,
> +  this function will return the variable memory address inside VariableStore,
> +  if given, via VariableInfo->Address; Otherwise, the address of other storage
> +  copies will be returned, if any.
> +
> +  For a new variable whose offset has not been determined, a value of -1 as
> +  VariableInfo->Offset should be passed to skip the offset calculation.
> +
> +  @param[in,out] VariableInfo             Pointer to variable information.
> +
> +  @retval EFI_INVALID_PARAMETER  VariableInfo is NULL or both VariableInfo-
> >Address
> +                                 and VariableInfo->Offset are NULL (0).
> +  @retval EFI_NOT_FOUND          If given Address or Offset is out of range of
> +                                 any given or internal storage copies.
> +  @retval EFI_SUCCESS            Variable details are retrieved successfully.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +GetVariableInfo (
> +  IN OUT  PROTECTED_VARIABLE_INFO  *VariableInfo
> +  )
> +{
> +  VARIABLE_STORE_HEADER          *Stores[2];
> +  UINTN                          Index;
> +  VARIABLE_HEADER                *VariablePtr;
> +  VARIABLE_HEADER                *VariableBuffer;
> +  AUTHENTICATED_VARIABLE_HEADER  *AuthVariablePtr;
> +  BOOLEAN                        AuthFlag;
> +  UINTN                          NameSize;
> +  UINTN                          DataSize;
> +  UINTN                          VariableSize;
> +
> +  if ((VariableInfo == NULL) || (  (VariableInfo->Buffer == NULL)
> +                                && (VariableInfo->StoreIndex == VAR_INDEX_INVALID)))
> +  {
> +    ASSERT (VariableInfo != NULL);
> +    ASSERT (VariableInfo->Buffer != NULL || VariableInfo->StoreIndex !=
> VAR_INDEX_INVALID);
> +    return EFI_INVALID_PARAMETER;
> +  }
> +
> +  Stores[0] = mNvVariableCache;
> +  Stores[1] = (mVariableModuleGlobal != NULL)
> +              ? (VARIABLE_STORE_HEADER *)(UINTN)mVariableModuleGlobal-
> >VariableGlobal.NonVolatileVariableBase
> +              : NULL;
> +
> +  VariableBuffer = VariableInfo->Buffer;
> +  VariablePtr    = NULL;
> +  if (VariableInfo->StoreIndex != VAR_INDEX_INVALID) {
> +    for (Index = 0; Index < ARRAY_SIZE (Stores); ++Index) {
> +      if (Stores[Index] == NULL) {
> +        continue;
> +      }
> +
> +      if ((UINTN)VariableInfo->StoreIndex
> +          < ((UINTN)GetEndPointer (Stores[Index]) - (UINTN)Stores[Index]))
> +      {
> +        VariablePtr          = (VARIABLE_HEADER *)((UINTN)Stores[Index] +
> (UINTN)VariableInfo->StoreIndex);
> +        VariableInfo->Buffer = VariablePtr;
> +        break;
> +      }
> +    }
> +  } else {
> +    VariablePtr = VariableInfo->Buffer;
> +  }
> +
> +  if (VariablePtr == NULL) {
> +    return EFI_NOT_FOUND;
> +  }
> +
> +  AuthFlag = VariableInfo->Flags.Auth;
> +  ASSERT (AuthFlag == TRUE || AuthFlag == FALSE);
> +
> +  //
> +  // Make a copy of the whole variable if a buffer is passed in.
> +  //
> +  if ((VariableBuffer != NULL) && (VariableBuffer != VariablePtr)) {
> +    VariableSize = (UINTN)GetNextVariablePtr (VariablePtr, AuthFlag)
> +                   - (UINTN)VariablePtr;
> +    CopyMem (VariableBuffer, VariablePtr, VariableSize);
> +  }
> +
> +  //
> +  // AuthVariable header
> +  //
> +  if (AuthFlag) {
> +    AuthVariablePtr = (AUTHENTICATED_VARIABLE_HEADER *)VariablePtr;
> +
> +    VariableInfo->Header.State          = AuthVariablePtr->State;
> +    VariableInfo->Header.Attributes     = AuthVariablePtr->Attributes;
> +    VariableInfo->Header.PubKeyIndex    = AuthVariablePtr->PubKeyIndex;
> +    VariableInfo->Header.MonotonicCount = ReadUnaligned64 (
> +                                            &(AuthVariablePtr->MonotonicCount)
> +                                            );
> +    if (VariableInfo->Header.TimeStamp != NULL) {
> +      CopyMem (
> +        VariableInfo->Header.TimeStamp,
> +        &AuthVariablePtr->TimeStamp,
> +        sizeof (EFI_TIME)
> +        );
> +    } else if (VariableBuffer != NULL) {
> +      AuthVariablePtr                = (AUTHENTICATED_VARIABLE_HEADER
> *)VariableBuffer;
> +      VariableInfo->Header.TimeStamp = &AuthVariablePtr->TimeStamp;
> +    }
> +  } else {
> +    VariableInfo->Header.State          = VariablePtr->State;
> +    VariableInfo->Header.Attributes     = VariablePtr->Attributes;
> +    VariableInfo->Header.PubKeyIndex    = 0;
> +    VariableInfo->Header.MonotonicCount = 0;
> +    VariableInfo->Header.TimeStamp      = NULL;
> +  }
> +
> +  //
> +  // VendorGuid
> +  //
> +  if (VariableInfo->Header.VendorGuid != NULL) {
> +    CopyGuid (
> +      VariableInfo->Header.VendorGuid,
> +      GetVendorGuidPtr (VariablePtr, AuthFlag)
> +      );
> +  } else {
> +    VariableInfo->Header.VendorGuid = GetVendorGuidPtr (VariablePtr,
> AuthFlag);
> +  }
> +
> +  //
> +  // VariableName
> +  //
> +  NameSize = NameSizeOfVariable (VariablePtr, AuthFlag);
> +  if (  (VariableInfo->Header.VariableName != NULL)
> +     && (VariableInfo->Header.NameSize >= NameSize))
> +  {
> +    CopyMem (
> +      VariableInfo->Header.VariableName,
> +      GetVariableNamePtr (VariablePtr, AuthFlag),
> +      NameSize
> +      );
> +  } else if (VariableInfo->Header.VariableName != NULL) {
> +    return EFI_BUFFER_TOO_SMALL;
> +  } else {
> +    VariableInfo->Header.VariableName = GetVariableNamePtr (VariablePtr,
> AuthFlag);
> +  }
> +
> +  //
> +  // Data
> +  //
> +  DataSize = DataSizeOfVariable (VariablePtr, AuthFlag);
> +  if (  (VariableInfo->Header.Data != NULL)
> +     && (VariableInfo->Header.DataSize >= DataSize))
> +  {
> +    CopyMem (
> +      VariableInfo->Header.Data,
> +      GetVariableDataPtr (VariablePtr, AuthFlag),
> +      NameSize
> +      );
> +  } else if (VariableInfo->Header.Data != NULL) {
> +    return EFI_BUFFER_TOO_SMALL;
> +  } else {
> +    VariableInfo->Header.Data = GetVariableDataPtr (VariablePtr, AuthFlag);
> +  }
> +
> +  //
> +  // Update size information about name & data.
> +  //
> +  VariableInfo->Header.NameSize = NameSize;
> +  VariableInfo->Header.DataSize = DataSize;
> +
> +  return EFI_SUCCESS;
> +}
> +
> +/**
> +
> +  Retrieve details of the variable next to given variable within VariableStore.
> +
> +  If VarInfo->Address is NULL, the first one in VariableStore is returned.
> +
> +  VariableStart and/or VariableEnd can be given optionally for the situation
> +  in which the valid storage space is smaller than the VariableStore->Size.
> +  This usually happens when PEI variable services make a compact variable
> +  cache to save memory, which cannot make use VariableStore->Size to
> determine
> +  the correct variable storage range.
> +
> +  @param[in,out] VariableInfo             Pointer to variable information.
> +
> +  @retval EFI_INVALID_PARAMETER  VariableInfo or VariableStore is NULL.
> +  @retval EFI_NOT_FOUND          If the end of VariableStore is reached.
> +  @retval EFI_SUCCESS            The next variable is retrieved successfully.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +GetNextVariableInfo (
> +  IN OUT  PROTECTED_VARIABLE_INFO  *VariableInfo
> +  )
> +{
> +  VARIABLE_STORE_HEADER  *VarStore;
> +  VARIABLE_HEADER        *VariablePtr;
> +  VARIABLE_HEADER        *VariableStart;
> +  VARIABLE_HEADER        *VariableEnd;
> +  BOOLEAN                AuthFlag;
> +
> +  if (VariableInfo == NULL) {
> +    ASSERT (VariableInfo != NULL);
> +    return EFI_INVALID_PARAMETER;
> +  }
> +
> +  if (mNvVariableCache != NULL) {
> +    VarStore = mNvVariableCache;
> +  } else if (mVariableModuleGlobal != NULL) {
> +    VarStore = (VARIABLE_STORE_HEADER *)(UINTN)
> +               mVariableModuleGlobal->VariableGlobal.NonVolatileVariableBase;
> +  } else {
> +    return EFI_NOT_FOUND;
> +  }
> +
> +  VariableStart = GetStartPointer (VarStore);
> +  VariableEnd   = GetEndPointer (VarStore);
> +
> +  if ((VariableInfo->Flags.Auth != TRUE) && (VariableInfo->Flags.Auth != FALSE))
> {
> +    VariableInfo->Flags.Auth = CompareGuid (
> +                                 &VarStore->Signature,
> +                                 &gEfiAuthenticatedVariableGuid
> +                                 );
> +  }
> +
> +  AuthFlag = VariableInfo->Flags.Auth;
> +
> +  if (VariableInfo->StoreIndex == VAR_INDEX_INVALID) {
> +    VariablePtr = VariableStart;
> +  } else {
> +    VariablePtr = (VARIABLE_HEADER *)
> +                  ((UINTN)VarStore + (UINTN)VariableInfo->StoreIndex);
> +    if (VariablePtr >= VariableEnd) {
> +      return EFI_NOT_FOUND;
> +    }
> +
> +    VariablePtr = GetNextVariablePtr (VariablePtr, AuthFlag);
> +  }
> +
> +  if (!IsValidVariableHeader (VariablePtr, VariableEnd, AuthFlag)) {
> +    return EFI_NOT_FOUND;
> +  }
> +
> +  VariableInfo->StoreIndex = (UINTN)VariablePtr - (UINTN)VarStore;
> +  return GetVariableInfo (VariableInfo);
> +}
> diff --git
> a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeCache.c
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeCache.c
> index 9bb30bc1e804..dc319feee727 100644
> --- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeCache.c
> +++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeCache.c
> @@ -7,7 +7,7 @@
>    This external input must be validated carefully to avoid security issue like
>    buffer overflow, integer overflow.
> 
> -Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2019 - 2022, Intel Corporation. All rights reserved.<BR>
[JianJW] 
It looks that there's no other changes in this file. No need to update the year.

>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c
> index 517cae7b00f8..c2b689f6202d 100644
> --- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c
> +++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c
> @@ -14,7 +14,7 @@
>    VariableServiceSetVariable(), VariableServiceQueryVariableInfo(),
> ReclaimForOS(),
>    SmmVariableGetStatistics() should also do validation based on its own
> knowledge.
> 
> -Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2010 - 2022, Intel Corporation. All rights reserved.<BR>
>  Copyright (c) 2018, Linaro, Ltd. All rights reserved.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
> @@ -1045,6 +1045,13 @@ VariableWriteServiceInitializeSmm (
>  {
>    EFI_STATUS  Status;
> 
> +  Status = ProtectedVariableLibWriteInit ();
> +  if (EFI_ERROR (Status) && (Status != EFI_UNSUPPORTED)) {
> +    DEBUG ((DEBUG_ERROR, "Variable protection service: write-init failed.
> Status = %r\n", Status));
> +    ASSERT_EFI_ERROR (Status);
> +    return;
> +  }
> +
>    Status = VariableWriteServiceInitialize ();
>    if (EFI_ERROR (Status)) {
>      DEBUG ((DEBUG_ERROR, "Variable write service initialization failed. Status
> = %r\n", Status));
> @@ -1143,10 +1150,32 @@ MmVariableServiceInitialize (
>    VOID
>    )
>  {
> -  EFI_STATUS  Status;
> -  EFI_HANDLE  VariableHandle;
> -  VOID        *SmmFtwRegistration;
> -  VOID        *SmmEndOfDxeRegistration;
> +  EFI_STATUS                     Status;
> +  EFI_HANDLE                     VariableHandle;
> +  VOID                           *SmmFtwRegistration;
> +  VOID                           *SmmEndOfDxeRegistration;
> +  PROTECTED_VARIABLE_CONTEXT_IN  ContextIn;
> +
> +  //
> +  // Initialize protected variable service, if enabled.
> +  //
> +  ContextIn.StructSize    = sizeof (ContextIn);
> +  ContextIn.StructVersion =
> PROTECTED_VARIABLE_CONTEXT_IN_STRUCT_VERSION;
> +
> +  ContextIn.FindVariableSmm     = NULL;
> +  ContextIn.GetVariableInfo     = GetVariableInfo;
> +  ContextIn.GetNextVariableInfo = GetNextVariableInfo;
> +  ContextIn.UpdateVariableStore = VariableExLibUpdateNvVariable;
> +  ContextIn.UpdateVariable      = VariableExLibUpdateVariable;
> +
> +  ContextIn.MaxVariableSize     = (UINT32)GetMaxVariableSize ();
> +  ContextIn.VariableServiceUser = FromSmmModule;
> +
> +  Status = ProtectedVariableLibInitialize (&ContextIn);
> +  if (EFI_ERROR (Status) && (Status != EFI_UNSUPPORTED)) {
> +    ASSERT_EFI_ERROR (Status);
> +    return Status;
> +  }
> 
>    //
>    // Variable initialize.
> diff --git
> a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.c
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.c
> index 4aaeb5ba8806..8fb8679671ad 100644
> ---
> a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.c
> +++
> b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.c
> @@ -13,7 +13,7 @@
> 
>    InitCommunicateBuffer() is really function to check the variable data size.
> 
> -Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2010 - 2022, Intel Corporation. All rights reserved.<BR>
>  Copyright (c) Microsoft Corporation.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
> @@ -36,11 +36,13 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
>  #include <Library/UefiLib.h>
>  #include <Library/BaseLib.h>
>  #include <Library/MmUnblockMemoryLib.h>
> +#include <Library/IoLib.h>
[JianJW] 
I didn't find any interface from IoLib.h used this file.

> 
>  #include <Guid/EventGroup.h>
>  #include <Guid/SmmVariableCommon.h>
> 
>  #include "PrivilegePolymorphic.h"
> +#include "Variable.h"
>  #include "VariableParsing.h"
> 
>  EFI_HANDLE                      mHandle                              = NULL;
> @@ -53,6 +55,8 @@ VARIABLE_INFO_ENTRY             *mVariableInfo
> = NULL;
>  VARIABLE_STORE_HEADER           *mVariableRuntimeHobCacheBuffer      = NULL;
>  VARIABLE_STORE_HEADER           *mVariableRuntimeNvCacheBuffer       = NULL;
>  VARIABLE_STORE_HEADER           *mVariableRuntimeVolatileCacheBuffer =
> NULL;
> +VARIABLE_STORE_HEADER           *mNvVariableCache                    = NULL;
> +VARIABLE_MODULE_GLOBAL          *mVariableModuleGlobal               = NULL;
>  UINTN                           mVariableBufferSize;
>  UINTN                           mVariableRuntimeHobCacheBufferSize;
>  UINTN                           mVariableRuntimeNvCacheBufferSize;
> @@ -616,7 +620,6 @@ FindVariableInRuntimeCache (
>    )
>  {
>    EFI_STATUS              Status;
> -  UINTN                   TempDataSize;
>    VARIABLE_POINTER_TRACK  RtPtrTrack;
>    VARIABLE_STORE_TYPE     StoreType;
>    VARIABLE_STORE_HEADER   *VariableStoreList[VariableStoreTypeMax];
> @@ -669,31 +672,23 @@ FindVariableInRuntimeCache (
>        //
>        // Get data size
>        //
> -      TempDataSize = DataSizeOfVariable (RtPtrTrack.CurrPtr,
> mVariableAuthFormat);
> -      ASSERT (TempDataSize != 0);
> -
> -      if (*DataSize >= TempDataSize) {
> -        if (Data == NULL) {
> -          Status = EFI_INVALID_PARAMETER;
> -          goto Done;
> -        }
> -
> -        CopyMem (Data, GetVariableDataPtr (RtPtrTrack.CurrPtr,
> mVariableAuthFormat), TempDataSize);
> -        *DataSize = TempDataSize;
> -
> -        UpdateVariableInfo (VariableName, VendorGuid, RtPtrTrack.Volatile, TRUE,
> FALSE, FALSE, TRUE, &mVariableInfo);
> -
> -        Status = EFI_SUCCESS;
> -        goto Done;
> -      } else {
> -        *DataSize = TempDataSize;
> -        Status    = EFI_BUFFER_TOO_SMALL;
> -        goto Done;
> +      if (!RtPtrTrack.Volatile) {
> +        //
> +        // Currently only non-volatile variable needs protection.
> +        //
> +        Status = ProtectedVariableLibGetByBuffer (RtPtrTrack.CurrPtr, Data,
> (UINT32 *)DataSize, mVariableAuthFormat);
> +      }
> +
> +      if (RtPtrTrack.Volatile || (Status == EFI_UNSUPPORTED)) {
> +        Status = GetVariableData (RtPtrTrack.CurrPtr, Data, (UINT32 *)DataSize,
> mVariableAuthFormat);
> +      }
> +
> +      if (!EFI_ERROR (Status)) {
> +        UpdateVariableInfo (VariableName, VendorGuid, RtPtrTrack.Volatile,
> TRUE, FALSE, FALSE, FALSE, &mVariableInfo);
>        }
>      }
>    }
> 
> -Done:
>    if ((Status == EFI_SUCCESS) || (Status == EFI_BUFFER_TOO_SMALL)) {
>      if ((Attributes != NULL) && (RtPtrTrack.CurrPtr != NULL)) {
>        *Attributes = RtPtrTrack.CurrPtr->Attributes;
> --
> 2.35.1.windows.2


^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [Patch v2 10/28] SecurityPkg: Add new KeyService types and defines
  2022-04-29 18:04 ` [Patch v2 10/28] SecurityPkg: Add new KeyService types and defines Judah Vang
@ 2022-05-22 14:06   ` Wang, Jian J
  0 siblings, 0 replies; 49+ messages in thread
From: Wang, Jian J @ 2022-05-22 14:06 UTC (permalink / raw)
  To: Vang, Judah, devel@edk2.groups.io; +Cc: Yao, Jiewen, Mistry, Nishant C

Judah,


> -----Original Message-----
> From: Vang, Judah <judah.vang@intel.com>
> Sent: Saturday, April 30, 2022 2:04 AM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Yao, Jiewen <jiewen.yao@intel.com>;
> Mistry, Nishant C <nishant.c.mistry@intel.com>
> Subject: [Patch v2 10/28] SecurityPkg: Add new KeyService types and defines
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594
> 
> Add new KeyService types and defines.
> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Judah Vang <judah.vang@intel.com>
> ---
>  SecurityPkg/Include/Ppi/KeyServicePpi.h | 57 ++++++++++++++++++++
>  1 file changed, 57 insertions(+)
> 
> diff --git a/SecurityPkg/Include/Ppi/KeyServicePpi.h
> b/SecurityPkg/Include/Ppi/KeyServicePpi.h
> new file mode 100644
> index 000000000000..f126913d2d81
> --- /dev/null
> +++ b/SecurityPkg/Include/Ppi/KeyServicePpi.h
> @@ -0,0 +1,57 @@
> +/** @file
> +  Provides Key Services.
> +
> +Copyright (c) 2008 - 2018, Intel Corporation. All rights reserved.<BR>
[JianJW] 
2018 -> 2022

Regards,
Jian

> +SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +@par Specification Reference:
> +**/
> +
> +#ifndef PEI_KEY_SERVICE_PPI_H_
> +#define PEI_KEY_SERVICE_PPI_H_
> +///
> +/// KEY SERVICE PPI GUID
> +///
> +extern EFI_GUID  gKeyServicePpiGuid;
> +
> +/**
> +  Generate a new key from root key.
> +
> +  @param[in]   Salt                     Pointer to the salt(non-secret) value.
> +  @param[in]   SaltSize                 Salt size in bytes.
> +  @param[out]  NewKey                   Pointer to buffer to receive new key.
> +  @param[in]   NewKeySize               Size of new key bytes to generate.
> +
> +  @retval EFI_SUCCESS                   The function completed successfully
> +  @retval OTHER                         The function completed with failure.
> +**/
> +typedef
> +EFI_STATUS
> +(EFIAPI *KEY_SERVICE_GEN_KEY)(
> +  IN   UINT8        *Salt,
> +  IN   UINTN        SaltSize,
> +  OUT  UINT8        *NewKey,
> +  IN   UINTN        NewKeySize
> +  );
> +
> +#define KEY_SERVICE_PPI_REVISION  1
> +#define ROOT_KEY_LEN              64
> +#define SALT_SIZE_MIN_LEN         64
> +#define KEY_SERVICE_KEY_NAME      L"KEY_SERVICE_KEY"
> +
> +typedef struct {
> +  UINT8    RootKey[ROOT_KEY_LEN];
> +  UINT8    PreviousRootKey[ROOT_KEY_LEN];
> +} KEY_SERVICE_DATA;
> +
> +typedef struct _KEY_SERVICE_PPI KEY_SERVICE_PPI;
> +
> +///
> +/// KEY SERVICE PPI
> +/// The interface functions are for Key Service in PEI Phase
> +///
> +struct _KEY_SERVICE_PPI {
> +  KEY_SERVICE_GEN_KEY    GenerateKey; /// Generate Key
> +};
> +
> +#endif
> --
> 2.35.1.windows.2


^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [Patch v2 11/28] SecurityPkg: Update RPMC APIs with index
  2022-04-29 18:04 ` [Patch v2 11/28] SecurityPkg: Update RPMC APIs with index Judah Vang
@ 2022-05-22 14:07   ` Wang, Jian J
  0 siblings, 0 replies; 49+ messages in thread
From: Wang, Jian J @ 2022-05-22 14:07 UTC (permalink / raw)
  To: Vang, Judah, devel@edk2.groups.io; +Cc: Yao, Jiewen, Mistry, Nishant C

Reviewed-by: Jian J Wang <jian.j.wang@intel.com>

Regards,
Jian

> -----Original Message-----
> From: Vang, Judah <judah.vang@intel.com>
> Sent: Saturday, April 30, 2022 2:04 AM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Yao, Jiewen <jiewen.yao@intel.com>;
> Mistry, Nishant C <nishant.c.mistry@intel.com>
> Subject: [Patch v2 11/28] SecurityPkg: Update RPMC APIs with index
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594
> 
> Update RPMC APIs with index parameter because sometimes
> there are more than 1 RPMC counter on the platform.
> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Judah Vang <judah.vang@intel.com>
> ---
>  SecurityPkg/Library/RpmcLibNull/RpmcLibNull.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/SecurityPkg/Library/RpmcLibNull/RpmcLibNull.c
> b/SecurityPkg/Library/RpmcLibNull/RpmcLibNull.c
> index 792e48250e5d..557aeb6abf09 100644
> --- a/SecurityPkg/Library/RpmcLibNull/RpmcLibNull.c
> +++ b/SecurityPkg/Library/RpmcLibNull/RpmcLibNull.c
> @@ -1,7 +1,7 @@
>  /** @file
>    NULL RpmcLib instance for build purpose.
> 
> -Copyright (c) 2020, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2020 - 2022, Intel Corporation. All rights reserved.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> @@ -12,6 +12,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
>  /**
>    Requests the monotonic counter from the designated RPMC counter.
> 
> +  @param[in]    CounterIndex            The RPMC index
>    @param[out]   CounterValue            A pointer to a buffer to store the RPMC
> value.
> 
>    @retval       EFI_SUCCESS             The operation completed successfully.
> @@ -21,6 +22,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
>  EFI_STATUS
>  EFIAPI
>  RequestMonotonicCounter (
> +  IN  UINT8   CounterIndex,
>    OUT UINT32  *CounterValue
>    )
>  {
> @@ -31,6 +33,8 @@ RequestMonotonicCounter (
>  /**
>    Increments the monotonic counter in the SPI flash device by 1.
> 
> +  @param[in]    CounterIndex            The RPMC index
> +
>    @retval       EFI_SUCCESS             The operation completed successfully.
>    @retval       EFI_DEVICE_ERROR        A device error occurred while attempting
> to update the counter.
>    @retval       EFI_UNSUPPORTED         The operation is un-supported.
> @@ -38,7 +42,7 @@ RequestMonotonicCounter (
>  EFI_STATUS
>  EFIAPI
>  IncrementMonotonicCounter (
> -  VOID
> +  IN  UINT8  CounterIndex
>    )
>  {
>    ASSERT (FALSE);
> --
> 2.35.1.windows.2


^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [Patch v2 12/28] SecurityPkg: Add new variable types and functions
  2022-04-29 18:04 ` [Patch v2 12/28] SecurityPkg: Add new variable types and functions Judah Vang
@ 2022-05-22 14:12   ` Wang, Jian J
  0 siblings, 0 replies; 49+ messages in thread
From: Wang, Jian J @ 2022-05-22 14:12 UTC (permalink / raw)
  To: Vang, Judah, devel@edk2.groups.io; +Cc: Yao, Jiewen, Mistry, Nishant C

Judah,

Patch 11 is a library instance of RpmcLib which relies on changes introduced in this patch (12).
You need to put this patch before patch 11.

Regards,
Jian

> -----Original Message-----
> From: Vang, Judah <judah.vang@intel.com>
> Sent: Saturday, April 30, 2022 2:04 AM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Yao, Jiewen <jiewen.yao@intel.com>;
> Mistry, Nishant C <nishant.c.mistry@intel.com>
> Subject: [Patch v2 12/28] SecurityPkg: Add new variable types and functions
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594
> 
> Add new variable encryption/decryption function prototypes.
> Add new variable digest structure. Add new Protected
> variable function prototypes. Update RPMC APIs to Add
> an index because there is could more than one counter.
> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Judah Vang <judah.vang@intel.com>
> ---
>  SecurityPkg/Include/Library/RpmcLib.h        | 15 +++++---
>  SecurityPkg/Include/Library/VariableKeyLib.h | 37 +++-----------------
>  2 files changed, 16 insertions(+), 36 deletions(-)
> 
> diff --git a/SecurityPkg/Include/Library/RpmcLib.h
> b/SecurityPkg/Include/Library/RpmcLib.h
> index df4ba34ba8cf..cb71dfcd7e4d 100644
> --- a/SecurityPkg/Include/Library/RpmcLib.h
> +++ b/SecurityPkg/Include/Library/RpmcLib.h
> @@ -1,19 +1,23 @@
>  /** @file
>    Public definitions for the Replay Protected Monotonic Counter (RPMC) Library.
> 
> -Copyright (c) 2020, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2020 - 2022, Intel Corporation. All rights reserved.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> 
> -#ifndef _RPMC_LIB_H_
> -#define _RPMC_LIB_H_
> +#ifndef RPMC_LIB_H_
> +#define RPMC_LIB_H_
> 
>  #include <Uefi/UefiBaseType.h>
> 
> +#define RPMC_COUNTER_1  0
> +#define RPMC_COUNTER_2  1
> +
>  /**
>    Requests the monotonic counter from the designated RPMC counter.
> 
> +  @param[in]    CounterIndex            The RPMC index
>    @param[out]   CounterValue            A pointer to a buffer to store the RPMC
> value.
> 
>    @retval       EFI_SUCCESS             The operation completed successfully.
> @@ -23,12 +27,15 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
>  EFI_STATUS
>  EFIAPI
>  RequestMonotonicCounter (
> +  IN  UINT8   CounterIndex,
>    OUT UINT32  *CounterValue
>    );
> 
>  /**
>    Increments the monotonic counter in the SPI flash device by 1.
> 
> +  @param[in]    CounterIndex            The RPMC index
> +
>    @retval       EFI_SUCCESS             The operation completed successfully.
>    @retval       EFI_DEVICE_ERROR        A device error occurred while attempting
> to update the counter.
>    @retval       EFI_UNSUPPORTED         The operation is un-supported.
> @@ -36,7 +43,7 @@ RequestMonotonicCounter (
>  EFI_STATUS
>  EFIAPI
>  IncrementMonotonicCounter (
> -  VOID
> +  IN  UINT8  CounterIndex
>    );
> 
>  #endif
> diff --git a/SecurityPkg/Include/Library/VariableKeyLib.h
> b/SecurityPkg/Include/Library/VariableKeyLib.h
> index 561ebad09da2..6076c4d4731b 100644
> --- a/SecurityPkg/Include/Library/VariableKeyLib.h
> +++ b/SecurityPkg/Include/Library/VariableKeyLib.h
> @@ -1,13 +1,13 @@
>  /** @file
>    Public definitions for Variable Key Library.
> 
> -Copyright (c) 2020, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2020 - 2022, Intel Corporation. All rights reserved.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> 
> -#ifndef _VARIABLE_KEY_LIB_H_
> -#define _VARIABLE_KEY_LIB_H_
> +#ifndef VARIABLE_KEY_LIB_H_
> +#define VARIABLE_KEY_LIB_H_
> 
>  #include <Uefi/UefiBaseType.h>
> 
> @@ -25,35 +25,8 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
>  EFI_STATUS
>  EFIAPI
>  GetVariableKey (
> -  OUT VOID       **VariableKey,
> -  IN  OUT UINTN  *VariableKeySize
> -  );
> -
> -/**
> -  Regenerates the variable key.
> -
> -  @retval       EFI_SUCCESS             The variable key was regenerated successfully.
> -  @retval       EFI_DEVICE_ERROR        An error occurred while attempting to
> regenerate the key.
> -  @retval       EFI_ACCESS_DENIED       The function was invoked after locking
> the key interface.
> -  @retval       EFI_UNSUPPORTED         Key regeneration is not supported in the
> current boot configuration.
> -**/
> -EFI_STATUS
> -EFIAPI
> -RegenerateVariableKey (
> -  VOID
> -  );
> -
> -/**
> -  Locks the regenerate key interface.
> -
> -  @retval       EFI_SUCCESS             The key interface was locked successfully.
> -  @retval       EFI_UNSUPPORTED         Locking the key interface is not supported
> in the current boot configuration.
> -  @retval       Others                  An error occurred while attempting to lock the
> key interface.
> -**/
> -EFI_STATUS
> -EFIAPI
> -LockVariableKeyInterface (
> -  VOID
> +  OUT VOID   *VariableKey,
> +  IN  UINTN  VariableKeySize
>    );
> 
>  #endif
> --
> 2.35.1.windows.2


^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [Patch v2 13/28] SecurityPkg: Fix GetVariableKey API
  2022-04-29 18:04 ` [Patch v2 13/28] SecurityPkg: Fix GetVariableKey API Judah Vang
@ 2022-05-22 14:15   ` Wang, Jian J
  0 siblings, 0 replies; 49+ messages in thread
From: Wang, Jian J @ 2022-05-22 14:15 UTC (permalink / raw)
  To: Vang, Judah, devel@edk2.groups.io; +Cc: Yao, Jiewen, Mistry, Nishant C

Judah,

My comments below

> -----Original Message-----
> From: Vang, Judah <judah.vang@intel.com>
> Sent: Saturday, April 30, 2022 2:04 AM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Yao, Jiewen <jiewen.yao@intel.com>;
> Mistry, Nishant C <nishant.c.mistry@intel.com>
> Subject: [Patch v2 13/28] SecurityPkg: Fix GetVariableKey API
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594
> 
> Fix GetVariableKey API to match changes in header files.
> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Judah Vang <judah.vang@intel.com>
> ---
>  SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.c
> b/SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.c
> index a08def767b5f..cfbad54ba106 100644
> --- a/SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.c
> +++ b/SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.c
> @@ -1,7 +1,7 @@
>  /** @file
>    Null version of VariableKeyLib for build purpose. Don't use it in real product.
> 
> -Copyright (c) 2020, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2020 - 2022, Intel Corporation. All rights reserved.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> @@ -22,8 +22,8 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
>  EFI_STATUS
>  EFIAPI
>  GetVariableKey (
> -  OUT VOID       **VariableKey,
> -  IN  OUT UINTN  *VariableKeySize
> +  OUT VOID   *VariableKey,
> +  IN  UINTN  VariableKeySize
[JianJW] 
'OUT' is removed here but the parameter description in function comments
still declared as [in,out]. Please update the function comments in patch 12 
as well.

Regards,
Jian
>    )
>  {
>    ASSERT (FALSE);
> --
> 2.35.1.windows.2


^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [Patch v2 14/28] SecurityPkg: Add null encryption variable libs
  2022-04-29 18:04 ` [Patch v2 14/28] SecurityPkg: Add null encryption variable libs Judah Vang
@ 2022-05-22 14:20   ` Wang, Jian J
  0 siblings, 0 replies; 49+ messages in thread
From: Wang, Jian J @ 2022-05-22 14:20 UTC (permalink / raw)
  To: Vang, Judah, devel@edk2.groups.io; +Cc: Yao, Jiewen, Mistry, Nishant C

Judah,

My comments below

> -----Original Message-----
> From: Vang, Judah <judah.vang@intel.com>
> Sent: Saturday, April 30, 2022 2:04 AM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Yao, Jiewen <jiewen.yao@intel.com>;
> Mistry, Nishant C <nishant.c.mistry@intel.com>
> Subject: [Patch v2 14/28] SecurityPkg: Add null encryption variable libs
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2594
> 
> Provide null ecryption variable libraries.
> These will be used by default for platforms that don't
> support protected variable encryption.
> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> Signed-off-by: Nishant C Mistry <nishant.c.mistry@intel.com>
> Signed-off-by: Judah Vang <judah.vang@intel.com>
> ---
>  SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf |
> 38 +++++++
>  SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariable.c          | 107
> ++++++++++++++++++++
>  SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.uni |
> 16 +++
>  3 files changed, 161 insertions(+)
> 
> diff --git
> a/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf
> b/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf
> new file mode 100644
> index 000000000000..ff5631b336eb
> --- /dev/null
> +++
> b/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf
> @@ -0,0 +1,38 @@
> +## @file
> +#  Provides NULL version of encryption variable services.
> +#
> +#  Copyright (c) 2015 - 2022, Intel Corporation. All rights reserved.<BR>
> +#
> +#  SPDX-License-Identifier: BSD-2-Clause-Patent
> +#
> +##
> +
> +[Defines]
> +  INF_VERSION                    = 0x00010005
> +  BASE_NAME                      = EncryptionVariableLibNull
> +  MODULE_UNI_FILE                = EncryptionVariableLib.uni
> +  FILE_GUID                      = 3972E6FE-74D5-45C3-A9FB-DB9E5E5C9C17
> +  MODULE_TYPE                    = BASE
> +  VERSION_STRING                 = 1.0
> +  LIBRARY_CLASS                  = EncryptionVariableLib
> +
> +#
> +# The following information is for reference only and not required by the build
> tools.
> +#
> +#  VALID_ARCHITECTURES           = IA32 X64
> +#
> +
> +[Sources]
> +  EncryptionVariable.c
> +
> +[Packages]
> +  MdePkg/MdePkg.dec
> +  MdeModulePkg/MdeModulePkg.dec
> +  SecurityPkg/SecurityPkg.dec
> +
> +[LibraryClasses]
> +  BaseLib
> +  DebugLib
> +
> +[Guids]
[JianJW] 
No GUID consumed here. Suggest removing this section.

> +
> diff --git a/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariable.c
> b/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariable.c
> new file mode 100644
> index 000000000000..58a4ae9f4282
> --- /dev/null
> +++ b/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariable.c
> @@ -0,0 +1,107 @@
> +/** @file
> +  The common variable operation routines shared by DXE_RUNTIME variable
> +  module and DXE_SMM variable module.
> +
> +  Caution: This module requires additional review when modified.
> +  This driver will have external input - variable data. They may be input in SMM
> mode.
> +  This external input must be validated carefully to avoid security issue like
> +  buffer overflow, integer overflow.
> +
> +  VariableServiceGetNextVariableName () and
> VariableServiceQueryVariableInfo() are external API.
> +  They need check input parameter.
> +
> +  VariableServiceGetVariable() and VariableServiceSetVariable() are external API
> +  to receive datasize and data buffer. The size should be checked carefully.
> +
> +  VariableServiceSetVariable() should also check authenticate data to avoid
> buffer overflow,
> +  integer overflow. It should also check attribute to avoid authentication bypass.
> +
[JianJW] 
The file header comment seems irrelevant.

> +Copyright (c) 2019 - 2022, Intel Corporation. All rights reserved.<BR>
> +SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#include <Uefi.h>
> +
> +#include <Library/EncryptionVariableLib.h>
> +#include <Library/DebugLib.h>
> +
> +/**
> +  Encrypt variable data.
> +
> +  Null version.
> +
> +  @param[in, out]   VarEncInfo   Pointer to structure containing detailed
> +                                 information about a variable.
> +
> +  @retval EFI_UNSUPPORTED         Unsupported to encrypt variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +EncryptVariable (
> +  IN OUT VARIABLE_ENCRYPTION_INFO  *VarEncInfo
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +  Decrypt variable data.
> +
> +  Null version.
> +
> +  @param[in, out]   VarEncInfo   Pointer to structure containing detailed
> +                                 information about a variable.
> +
> +  @retval EFI_UNSUPPORTED         Unsupported to encrypt variable.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +DecryptVariable (
> +  IN OUT VARIABLE_ENCRYPTION_INFO  *VarEncInfo
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +  Get cipher information.
> +
> +  Null version.
> +
> +  @param[in]   VarEncInfo   Pointer to structure containing detailed
> +                            information about a variable.
> +
> +  @retval EFI_UNSUPPORTED         Unsupported interface.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +GetCipherDataInfo (
> +  IN VARIABLE_ENCRYPTION_INFO  *VarEncInfo
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> +
> +/**
> +  Set cipher information for a variable.
> +
> +  Null version.
> +
> +  @param[in]   VarEncInfo   Pointer to structure containing detailed
> +                            information about a variable.
> +
> +  @retval EFI_UNSUPPORTED         If this method is not supported.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +SetCipherDataInfo (
> +  IN VARIABLE_ENCRYPTION_INFO  *VarEncInfo
> +  )
> +{
> +  return EFI_UNSUPPORTED;
> +}
> diff --git
> a/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.uni
> b/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.uni
> new file mode 100644
> index 000000000000..856fa201b8df
> --- /dev/null
> +++
> b/SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.uni
> @@ -0,0 +1,16 @@
> +// /** @file
> +// Provides authenticated variable services.
> +//
> +// Provides authenticated variable services.
> +//
[JianJW] 
The file header is irrelevant.

Regards,
Jian

> +// Copyright (c) 2015 - 2022, Intel Corporation. All rights reserved.<BR>
> +//
> +// SPDX-License-Identifier: BSD-2-Clause-Patent
> +//
> +// **/
> +
> +
> +#string STR_MODULE_ABSTRACT             #language en-US "Provides
> authenticated variable services"
> +
> +#string STR_MODULE_DESCRIPTION          #language en-US "Provides
> authenticated variable services."
> +
> --
> 2.35.1.windows.2


^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [edk2-devel] [Patch v2 00/28] UEFI variable protection
       [not found] ` <16EFC4965F71DFB8.20068@groups.io>
@ 2022-06-16 19:13   ` Michael Kubacki
  2022-08-23  3:35     ` Michael Kubacki
  0 siblings, 1 reply; 49+ messages in thread
From: Michael Kubacki @ 2022-06-16 19:13 UTC (permalink / raw)
  To: devel, judah.vang

Do you have the data below?

This is important for platform adoption and would be useful to include 
in the following section.

https://github.com/judahvang/edk2/tree/rpmc-update#platform-integration-considerations

Thanks,
Michael

On 5/16/2022 10:48 PM, Michael Kubacki wrote:
> Hi Judah,
> 
> Do you have reference information for the following?
> 
> 1. Overall boot time impact for a sample variable store?
> 
> -  In particular:
>    - Initial HMAC calculation/verification time.
>    - Non-volatile write impact time to caluclate new store HMAC value 
> and update MetaDataHmacVar.
>    - Variable reclaim before and after time.
> 
> 2. Overall non-volatile store size overhead impact with AES-CBC 
> encrypted variables?
> 
> I understand these will vary based on system properties like SPI flash 
> parameters, cryptographic processor details, etc. I'm trying to get an 
> idea of the impact from sample data or averages on a particular system 
> configuration. Also to learn whether the native encryption instruction 
> (AES-NI) was used and if that could provide any benefit given the 
> potential number of encryption/decryption operations introduced.
> 
> For the code design, I feel the ProtectedVariableLib interface is a bit 
> too coupled against internal implementation details of the variable 
> driver. I generally understand why the code is split out to wrap 
> operations around the new functionality and it follows the AuthVarLib 
> pattern but changing the library or driver will continue to require 
> large changes across both like this due to the coupling.
> 
> Small things I noticed:
> 1. VariableKeyLib.inf should not be "BASE", it directly depends on PEI 
> services
> 2. Typo "varabile" in some files
> 3. Does ProtectedVariableLibNull actually need to depend on BaseMemoryLib?
> 
> Thanks,
> Michael
> 
> On 4/29/2022 2:04 PM, Judah Vang wrote:
>> For a more detail description of the UEFI variable protected feature 
>> you can
>> view the Readme.md located at the following location:
>> https://github.com/judahvang/edk2/tree/rpmc-update
>>
>>
>> Judah Vang (28):
>>    MdeModulePkg: Add new GUID for Variable Store Info
>>    SecurityPkg: Add new GUIDs for
>>    MdeModulePkg: Update AUTH_VARIABLE_INFO struct
>>    MdeModulePkg: Add reference to new Ppi Guid
>>    MdeModulePkg: Add new ProtectedVariable GUIDs
>>    MdeModulePkg: Add new include files
>>    MdeModulePkg: Add Null ProtectedVariable Library
>>    MdeModulePkg: Add new Variable functionality
>>    MdeModulePkg: Add support for Protected Variables
>>    SecurityPkg: Add new KeyService types and defines
>>    SecurityPkg: Update RPMC APIs with index
>>    SecurityPkg: Add new variable types and functions
>>    SecurityPkg: Fix GetVariableKey API
>>    SecurityPkg: Add null encryption variable libs
>>    SecurityPkg: Add VariableKey library function
>>    SecurityPkg: Add EncryptionVariable lib with AES
>>    SecurityPkg: Add Protected Variable Services
>>    MdeModulePkg: Reference Null ProtectedVariableLib
>>    SecurityPkg: Add references to new *.inf files
>>    ArmVirtPkg: Add reference to ProtectedVariableNull
>>    UefiPayloadPkg: Add ProtectedVariable reference
>>    EmulatorPkg: Add ProtectedVariable reference
>>    OvmfPkg: Add ProtectedVariable reference
>>    OvmfPkg: Add ProtectedVariableLib reference
>>    OvmfPkg: Add ProtectedVariableLib reference
>>    OvmfPkg: Add ProtectedVariableLib reference
>>    OvmfPkg: Add ProtectedVariable reference
>>    CryptoPkg: Enable cypto HMAC KDF library
>>
>>   
>> MdeModulePkg/MdeModulePkg.dec                                               
>> |   13 +-
>>   
>> SecurityPkg/SecurityPkg.dec                                                 
>> |   43 +-
>>   
>> ArmVirtPkg/ArmVirtQemu.dsc                                                  
>> |    3 +-
>>   
>> EmulatorPkg/EmulatorPkg.dsc                                                 
>> |    3 +-
>>   
>> MdeModulePkg/MdeModulePkg.dsc                                               
>> |    4 +-
>>   
>> OvmfPkg/AmdSev/AmdSevX64.dsc                                                
>> |    3 +-
>>   
>> OvmfPkg/Bhyve/BhyveX64.dsc                                                  
>> |    3 +-
>>   
>> OvmfPkg/CloudHv/CloudHvX64.dsc                                              
>> |    1 +
>>   
>> OvmfPkg/Microvm/MicrovmX64.dsc                                              
>> |    3 +-
>>   
>> OvmfPkg/OvmfPkgIa32.dsc                                                     
>> |    1 +
>>   
>> OvmfPkg/OvmfPkgIa32X64.dsc                                                  
>> |    1 +
>>   
>> OvmfPkg/OvmfPkgX64.dsc                                                      
>> |    1 +
>>   
>> OvmfPkg/OvmfXen.dsc                                                         
>> |    3 +-
>>   
>> SecurityPkg/SecurityPkg.dsc                                                 
>> |   13 +-
>>   
>> UefiPayloadPkg/UefiPayloadPkg.dsc                                           
>> |    2 +
>>   
>> CryptoPkg/Library/BaseCryptLib/SmmCryptLib.inf                              
>> |    2 +-
>>   
>> MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf  
>> |   34 +
>>   
>> MdeModulePkg/Universal/Variable/Pei/VariablePei.inf                         
>> |   10 +-
>>   
>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf           
>> |    3 +-
>>   
>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf                  
>> |    3 +-
>>   
>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.inf        
>> |    4 +-
>>   
>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf         
>> |    3 +-
>>   
>> SecurityPkg/Library/EncryptionVariableLib/EncryptionVariableLib.inf         
>> |   43 +
>>   
>> SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf 
>> |   38 +
>>   
>> SecurityPkg/Library/ProtectedVariableLib/DxeProtectedVariableLib.inf        
>> |   64 +
>>   
>> SecurityPkg/Library/ProtectedVariableLib/PeiProtectedVariableLib.inf        
>> |   68 +
>>   
>> SecurityPkg/Library/ProtectedVariableLib/SmmProtectedVariableLib.inf        
>> |   67 +
>>   
>> SecurityPkg/Library/ProtectedVariableLib/SmmRuntimeProtectedVariableLib.inf 
>> |   62 +
>>   
>> SecurityPkg/Library/VariableKeyLib/VariableKeyLib.inf                       
>> |   36 +
>>   
>> MdeModulePkg/Include/Guid/ProtectedVariable.h                               
>> |   22 +
>>   
>> MdeModulePkg/Include/Library/AuthVariableLib.h                              
>> |    4 +-
>>   
>> MdeModulePkg/Include/Library/EncryptionVariableLib.h                        
>> |  165 ++
>>   
>> MdeModulePkg/Include/Library/ProtectedVariableLib.h                         
>> |  700 +++++++
>>   
>> MdeModulePkg/Universal/Variable/Pei/Variable.h                              
>> |   80 +-
>>   
>> MdeModulePkg/Universal/Variable/Pei/VariableParsing.h                       
>> |  309 +++
>>   
>> MdeModulePkg/Universal/Variable/Pei/VariableStore.h                         
>> |  116 ++
>>   
>> MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h                       
>> |  126 +-
>>   
>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.h                
>> |   91 +-
>>   
>> MdePkg/Include/Ppi/ReadOnlyVariable2.h                                      
>> |    4 +-
>>   
>> SecurityPkg/Include/Library/RpmcLib.h                                       
>> |   15 +-
>>   
>> SecurityPkg/Include/Library/VariableKeyLib.h                                
>> |   37 +-
>>   
>> SecurityPkg/Include/Ppi/KeyServicePpi.h                                     
>> |   57 +
>>   
>> SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.h              
>> |   49 +
>>   
>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableInternal.h        
>> |  611 ++++++
>>   
>> MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariable.c           
>> |  449 ++++
>>   
>> MdeModulePkg/Universal/Variable/Pei/Variable.c                              
>> |  886 ++------
>>   
>> MdeModulePkg/Universal/Variable/Pei/VariableParsing.c                       
>> |  941 +++++++++
>>   
>> MdeModulePkg/Universal/Variable/Pei/VariableStore.c                         
>> |  305 +++
>>   
>> MdeModulePkg/Universal/Variable/RuntimeDxe/Reclaim.c                        
>> |  349 +++-
>>   
>> MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c                       
>> | 2139 +++++++++++---------
>>   
>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableDxe.c                    
>> |   26 +-
>>   
>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableExLib.c                  
>> |  167 +-
>>   
>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableNonVolatile.c            
>> |  194 +-
>>   
>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.c                
>> |  320 ++-
>>   
>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeCache.c           
>> |    2 +-
>>   
>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c                    
>> |   39 +-
>>   
>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.c          
>> |   41 +-
>>   
>> SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.c              
>> |  728 +++++++
>>   
>> SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariable.c          
>> |  107 +
>>   
>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableCommon.c          
>> | 2095 +++++++++++++++++++
>>   
>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableDxe.c             
>> |  163 ++
>>   
>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariablePei.c             
>> | 1331 ++++++++++++
>>   
>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmm.c             
>> |  209 ++
>>   
>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmDxeCommon.c    
>> |  975 +++++++++
>>   
>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmRuntime.c      
>> |  233 +++
>>   
>> SecurityPkg/Library/RpmcLibNull/RpmcLibNull.c                               
>> |    8 +-
>>   
>> SecurityPkg/Library/VariableKeyLib/VariableKeyLib.c                         
>> |   59 +
>>   
>> SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.c                 
>> |    6 +-
>>   
>> SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.uni 
>> |   16 +
>>   69 files changed, 12845 insertions(+), 1863 deletions(-)
>>   create mode 100644 
>> MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf 
>>
>>   create mode 100644 
>> SecurityPkg/Library/EncryptionVariableLib/EncryptionVariableLib.inf
>>   create mode 100644 
>> SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf 
>>
>>   create mode 100644 
>> SecurityPkg/Library/ProtectedVariableLib/DxeProtectedVariableLib.inf
>>   create mode 100644 
>> SecurityPkg/Library/ProtectedVariableLib/PeiProtectedVariableLib.inf
>>   create mode 100644 
>> SecurityPkg/Library/ProtectedVariableLib/SmmProtectedVariableLib.inf
>>   create mode 100644 
>> SecurityPkg/Library/ProtectedVariableLib/SmmRuntimeProtectedVariableLib.inf 
>>
>>   create mode 100644 
>> SecurityPkg/Library/VariableKeyLib/VariableKeyLib.inf
>>   create mode 100644 MdeModulePkg/Include/Guid/ProtectedVariable.h
>>   create mode 100644 MdeModulePkg/Include/Library/EncryptionVariableLib.h
>>   create mode 100644 MdeModulePkg/Include/Library/ProtectedVariableLib.h
>>   create mode 100644 
>> MdeModulePkg/Universal/Variable/Pei/VariableParsing.h
>>   create mode 100644 MdeModulePkg/Universal/Variable/Pei/VariableStore.h
>>   create mode 100644 SecurityPkg/Include/Ppi/KeyServicePpi.h
>>   create mode 100644 
>> SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.h
>>   create mode 100644 
>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableInternal.h
>>   create mode 100644 
>> MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariable.c
>>   create mode 100644 
>> MdeModulePkg/Universal/Variable/Pei/VariableParsing.c
>>   create mode 100644 MdeModulePkg/Universal/Variable/Pei/VariableStore.c
>>   create mode 100644 
>> SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.c
>>   create mode 100644 
>> SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariable.c
>>   create mode 100644 
>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableCommon.c
>>   create mode 100644 
>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableDxe.c
>>   create mode 100644 
>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariablePei.c
>>   create mode 100644 
>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmm.c
>>   create mode 100644 
>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmDxeCommon.c
>>   create mode 100644 
>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmRuntime.c
>>   create mode 100644 SecurityPkg/Library/VariableKeyLib/VariableKeyLib.c
>>   create mode 100644 
>> SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.uni 
>>
>>
> 
> 
> 
> 

^ permalink raw reply	[flat|nested] 49+ messages in thread

* Re: [edk2-devel] [Patch v2 00/28] UEFI variable protection
  2022-06-16 19:13   ` Michael Kubacki
@ 2022-08-23  3:35     ` Michael Kubacki
  0 siblings, 0 replies; 49+ messages in thread
From: Michael Kubacki @ 2022-08-23  3:35 UTC (permalink / raw)
  To: devel, judah.vang

Hi Judah,

Just wanted to send a reminder to see if you have this data from your 
testing.

Thanks,
Michael

On 6/16/2022 3:13 PM, Michael Kubacki wrote:
> Do you have the data below?
> 
> This is important for platform adoption and would be useful to include 
> in the following section.
> 
> https://github.com/judahvang/edk2/tree/rpmc-update#platform-integration-considerations 
> 
> 
> Thanks,
> Michael
> 
> On 5/16/2022 10:48 PM, Michael Kubacki wrote:
>> Hi Judah,
>>
>> Do you have reference information for the following?
>>
>> 1. Overall boot time impact for a sample variable store?
>>
>> -  In particular:
>>    - Initial HMAC calculation/verification time.
>>    - Non-volatile write impact time to caluclate new store HMAC value 
>> and update MetaDataHmacVar.
>>    - Variable reclaim before and after time.
>>
>> 2. Overall non-volatile store size overhead impact with AES-CBC 
>> encrypted variables?
>>
>> I understand these will vary based on system properties like SPI flash 
>> parameters, cryptographic processor details, etc. I'm trying to get an 
>> idea of the impact from sample data or averages on a particular system 
>> configuration. Also to learn whether the native encryption instruction 
>> (AES-NI) was used and if that could provide any benefit given the 
>> potential number of encryption/decryption operations introduced.
>>
>> For the code design, I feel the ProtectedVariableLib interface is a 
>> bit too coupled against internal implementation details of the 
>> variable driver. I generally understand why the code is split out to 
>> wrap operations around the new functionality and it follows the 
>> AuthVarLib pattern but changing the library or driver will continue to 
>> require large changes across both like this due to the coupling.
>>
>> Small things I noticed:
>> 1. VariableKeyLib.inf should not be "BASE", it directly depends on PEI 
>> services
>> 2. Typo "varabile" in some files
>> 3. Does ProtectedVariableLibNull actually need to depend on 
>> BaseMemoryLib?
>>
>> Thanks,
>> Michael
>>
>> On 4/29/2022 2:04 PM, Judah Vang wrote:
>>> For a more detail description of the UEFI variable protected feature 
>>> you can
>>> view the Readme.md located at the following location:
>>> https://github.com/judahvang/edk2/tree/rpmc-update
>>>
>>>
>>> Judah Vang (28):
>>>    MdeModulePkg: Add new GUID for Variable Store Info
>>>    SecurityPkg: Add new GUIDs for
>>>    MdeModulePkg: Update AUTH_VARIABLE_INFO struct
>>>    MdeModulePkg: Add reference to new Ppi Guid
>>>    MdeModulePkg: Add new ProtectedVariable GUIDs
>>>    MdeModulePkg: Add new include files
>>>    MdeModulePkg: Add Null ProtectedVariable Library
>>>    MdeModulePkg: Add new Variable functionality
>>>    MdeModulePkg: Add support for Protected Variables
>>>    SecurityPkg: Add new KeyService types and defines
>>>    SecurityPkg: Update RPMC APIs with index
>>>    SecurityPkg: Add new variable types and functions
>>>    SecurityPkg: Fix GetVariableKey API
>>>    SecurityPkg: Add null encryption variable libs
>>>    SecurityPkg: Add VariableKey library function
>>>    SecurityPkg: Add EncryptionVariable lib with AES
>>>    SecurityPkg: Add Protected Variable Services
>>>    MdeModulePkg: Reference Null ProtectedVariableLib
>>>    SecurityPkg: Add references to new *.inf files
>>>    ArmVirtPkg: Add reference to ProtectedVariableNull
>>>    UefiPayloadPkg: Add ProtectedVariable reference
>>>    EmulatorPkg: Add ProtectedVariable reference
>>>    OvmfPkg: Add ProtectedVariable reference
>>>    OvmfPkg: Add ProtectedVariableLib reference
>>>    OvmfPkg: Add ProtectedVariableLib reference
>>>    OvmfPkg: Add ProtectedVariableLib reference
>>>    OvmfPkg: Add ProtectedVariable reference
>>>    CryptoPkg: Enable cypto HMAC KDF library
>>>
>>> MdeModulePkg/MdeModulePkg.dec |   13 +-
>>> SecurityPkg/SecurityPkg.dec |   43 +-
>>> ArmVirtPkg/ArmVirtQemu.dsc |    3 +-
>>> EmulatorPkg/EmulatorPkg.dsc |    3 +-
>>> MdeModulePkg/MdeModulePkg.dsc |    4 +-
>>> OvmfPkg/AmdSev/AmdSevX64.dsc |    3 +-
>>> OvmfPkg/Bhyve/BhyveX64.dsc |    3 +-
>>> OvmfPkg/CloudHv/CloudHvX64.dsc |    1 +
>>> OvmfPkg/Microvm/MicrovmX64.dsc |    3 +-
>>> OvmfPkg/OvmfPkgIa32.dsc |    1 +
>>> OvmfPkg/OvmfPkgIa32X64.dsc |    1 +
>>> OvmfPkg/OvmfPkgX64.dsc |    1 +
>>> OvmfPkg/OvmfXen.dsc |    3 +-
>>> SecurityPkg/SecurityPkg.dsc |   13 +-
>>> UefiPayloadPkg/UefiPayloadPkg.dsc |    2 +
>>> CryptoPkg/Library/BaseCryptLib/SmmCryptLib.inf |    2 +-
>>> MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf 
>>> |   34 +
>>> MdeModulePkg/Universal/Variable/Pei/VariablePei.inf |   10 +-
>>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf 
>>> |    3 +-
>>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf |    3 +-
>>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.inf 
>>> |    4 +-
>>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf 
>>> |    3 +-
>>> SecurityPkg/Library/EncryptionVariableLib/EncryptionVariableLib.inf 
>>> |   43 +
>>> SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf 
>>> |   38 +
>>> SecurityPkg/Library/ProtectedVariableLib/DxeProtectedVariableLib.inf 
>>> |   64 +
>>> SecurityPkg/Library/ProtectedVariableLib/PeiProtectedVariableLib.inf 
>>> |   68 +
>>> SecurityPkg/Library/ProtectedVariableLib/SmmProtectedVariableLib.inf 
>>> |   67 +
>>> SecurityPkg/Library/ProtectedVariableLib/SmmRuntimeProtectedVariableLib.inf 
>>> |   62 +
>>> SecurityPkg/Library/VariableKeyLib/VariableKeyLib.inf |   36 +
>>> MdeModulePkg/Include/Guid/ProtectedVariable.h |   22 +
>>> MdeModulePkg/Include/Library/AuthVariableLib.h |    4 +-
>>> MdeModulePkg/Include/Library/EncryptionVariableLib.h |  165 ++
>>> MdeModulePkg/Include/Library/ProtectedVariableLib.h |  700 +++++++
>>> MdeModulePkg/Universal/Variable/Pei/Variable.h |   80 +-
>>> MdeModulePkg/Universal/Variable/Pei/VariableParsing.h |  309 +++
>>> MdeModulePkg/Universal/Variable/Pei/VariableStore.h |  116 ++
>>> MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h |  126 +-
>>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.h |   91 +-
>>> MdePkg/Include/Ppi/ReadOnlyVariable2.h |    4 +-
>>> SecurityPkg/Include/Library/RpmcLib.h |   15 +-
>>> SecurityPkg/Include/Library/VariableKeyLib.h |   37 +-
>>> SecurityPkg/Include/Ppi/KeyServicePpi.h |   57 +
>>> SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.h |   49 +
>>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableInternal.h 
>>> |  611 ++++++
>>> MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariable.c |  
>>> 449 ++++
>>> MdeModulePkg/Universal/Variable/Pei/Variable.c |  886 ++------
>>> MdeModulePkg/Universal/Variable/Pei/VariableParsing.c |  941 +++++++++
>>> MdeModulePkg/Universal/Variable/Pei/VariableStore.c |  305 +++
>>> MdeModulePkg/Universal/Variable/RuntimeDxe/Reclaim.c |  349 +++-
>>> MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c | 2139 
>>> +++++++++++---------
>>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableDxe.c |   26 +-
>>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableExLib.c |  167 +-
>>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableNonVolatile.c |  
>>> 194 +-
>>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.c |  320 ++-
>>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeCache.c 
>>> |    2 +-
>>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c |   39 +-
>>> MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmmRuntimeDxe.c 
>>> |   41 +-
>>> SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.c |  728 
>>> +++++++
>>> SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariable.c |  
>>> 107 +
>>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableCommon.c | 
>>> 2095 +++++++++++++++++++
>>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableDxe.c |  
>>> 163 ++
>>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariablePei.c | 
>>> 1331 ++++++++++++
>>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmm.c |  
>>> 209 ++
>>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmDxeCommon.c 
>>> |  975 +++++++++
>>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmRuntime.c |  
>>> 233 +++
>>> SecurityPkg/Library/RpmcLibNull/RpmcLibNull.c |    8 +-
>>> SecurityPkg/Library/VariableKeyLib/VariableKeyLib.c |   59 +
>>> SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.c |    6 +-
>>> SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.uni 
>>> |   16 +
>>>   69 files changed, 12845 insertions(+), 1863 deletions(-)
>>>   create mode 100644 
>>> MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariableLibNull.inf 
>>>
>>>   create mode 100644 
>>> SecurityPkg/Library/EncryptionVariableLib/EncryptionVariableLib.inf
>>>   create mode 100644 
>>> SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.inf 
>>>
>>>   create mode 100644 
>>> SecurityPkg/Library/ProtectedVariableLib/DxeProtectedVariableLib.inf
>>>   create mode 100644 
>>> SecurityPkg/Library/ProtectedVariableLib/PeiProtectedVariableLib.inf
>>>   create mode 100644 
>>> SecurityPkg/Library/ProtectedVariableLib/SmmProtectedVariableLib.inf
>>>   create mode 100644 
>>> SecurityPkg/Library/ProtectedVariableLib/SmmRuntimeProtectedVariableLib.inf 
>>>
>>>   create mode 100644 
>>> SecurityPkg/Library/VariableKeyLib/VariableKeyLib.inf
>>>   create mode 100644 MdeModulePkg/Include/Guid/ProtectedVariable.h
>>>   create mode 100644 
>>> MdeModulePkg/Include/Library/EncryptionVariableLib.h
>>>   create mode 100644 MdeModulePkg/Include/Library/ProtectedVariableLib.h
>>>   create mode 100644 
>>> MdeModulePkg/Universal/Variable/Pei/VariableParsing.h
>>>   create mode 100644 MdeModulePkg/Universal/Variable/Pei/VariableStore.h
>>>   create mode 100644 SecurityPkg/Include/Ppi/KeyServicePpi.h
>>>   create mode 100644 
>>> SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.h
>>>   create mode 100644 
>>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableInternal.h
>>>   create mode 100644 
>>> MdeModulePkg/Library/ProtectedVariableLibNull/ProtectedVariable.c
>>>   create mode 100644 
>>> MdeModulePkg/Universal/Variable/Pei/VariableParsing.c
>>>   create mode 100644 MdeModulePkg/Universal/Variable/Pei/VariableStore.c
>>>   create mode 100644 
>>> SecurityPkg/Library/EncryptionVariableLib/EncryptionVariable.c
>>>   create mode 100644 
>>> SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariable.c
>>>   create mode 100644 
>>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableCommon.c
>>>   create mode 100644 
>>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableDxe.c
>>>   create mode 100644 
>>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariablePei.c
>>>   create mode 100644 
>>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmm.c
>>>   create mode 100644 
>>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmDxeCommon.c
>>>   create mode 100644 
>>> SecurityPkg/Library/ProtectedVariableLib/ProtectedVariableSmmRuntime.c
>>>   create mode 100644 SecurityPkg/Library/VariableKeyLib/VariableKeyLib.c
>>>   create mode 100644 
>>> SecurityPkg/Library/EncryptionVariableLibNull/EncryptionVariableLibNull.uni 
>>>
>>>
>>
>>
>> 
>>

^ permalink raw reply	[flat|nested] 49+ messages in thread

end of thread, other threads:[~2022-08-23  3:35 UTC | newest]

Thread overview: 49+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2022-04-29 18:04 [Patch v2 00/28] UEFI variable protection Judah Vang
2022-04-29 18:04 ` [Patch v2 01/28] MdeModulePkg: Add new GUID for Variable Store Info Judah Vang
2022-05-12  9:32   ` Wang, Jian J
2022-04-29 18:04 ` [Patch v2 02/28] SecurityPkg: Add new GUIDs for Judah Vang
2022-05-12  9:33   ` Wang, Jian J
2022-04-29 18:04 ` [Patch v2 03/28] MdeModulePkg: Update AUTH_VARIABLE_INFO struct Judah Vang
2022-05-12  9:33   ` Wang, Jian J
2022-04-29 18:04 ` [Patch v2 04/28] MdeModulePkg: Add reference to new Ppi Guid Judah Vang
2022-05-12  9:32   ` Wang, Jian J
2022-04-29 18:04 ` [Patch v2 05/28] MdeModulePkg: Add new ProtectedVariable GUIDs Judah Vang
2022-05-12  9:32   ` Wang, Jian J
2022-04-29 18:04 ` [Patch v2 06/28] MdeModulePkg: Add new include files Judah Vang
2022-05-12  9:31   ` Wang, Jian J
2022-04-29 18:04 ` [Patch v2 07/28] MdeModulePkg: Add Null ProtectedVariable Library Judah Vang
2022-05-22  8:38   ` Wang, Jian J
2022-04-29 18:04 ` [Patch v2 08/28] MdeModulePkg: Add new Variable functionality Judah Vang
2022-05-22 10:24   ` Wang, Jian J
2022-04-29 18:04 ` [Patch v2 09/28] MdeModulePkg: Add support for Protected Variables Judah Vang
2022-05-22 14:03   ` Wang, Jian J
2022-04-29 18:04 ` [Patch v2 10/28] SecurityPkg: Add new KeyService types and defines Judah Vang
2022-05-22 14:06   ` Wang, Jian J
2022-04-29 18:04 ` [Patch v2 11/28] SecurityPkg: Update RPMC APIs with index Judah Vang
2022-05-22 14:07   ` Wang, Jian J
2022-04-29 18:04 ` [Patch v2 12/28] SecurityPkg: Add new variable types and functions Judah Vang
2022-05-22 14:12   ` Wang, Jian J
2022-04-29 18:04 ` [Patch v2 13/28] SecurityPkg: Fix GetVariableKey API Judah Vang
2022-05-22 14:15   ` Wang, Jian J
2022-04-29 18:04 ` [Patch v2 14/28] SecurityPkg: Add null encryption variable libs Judah Vang
2022-05-22 14:20   ` Wang, Jian J
2022-04-29 18:04 ` [Patch v2 15/28] SecurityPkg: Add VariableKey library function Judah Vang
2022-04-29 18:04 ` [Patch v2 16/28] SecurityPkg: Add EncryptionVariable lib with AES Judah Vang
2022-04-29 18:04 ` [Patch v2 17/28] SecurityPkg: Add Protected Variable Services Judah Vang
2022-04-29 18:04 ` [Patch v2 18/28] MdeModulePkg: Reference Null ProtectedVariableLib Judah Vang
2022-04-29 18:04 ` [Patch v2 19/28] SecurityPkg: Add references to new *.inf files Judah Vang
2022-04-29 18:04 ` [Patch v2 20/28] ArmVirtPkg: Add reference to ProtectedVariableNull Judah Vang
2022-05-03  7:29   ` Ard Biesheuvel
2022-04-29 18:04 ` [Patch v2 21/28] UefiPayloadPkg: Add ProtectedVariable reference Judah Vang
2022-04-29 21:03   ` Guo Dong
2022-04-29 18:04 ` [Patch v2 22/28] EmulatorPkg: " Judah Vang
2022-04-29 18:04 ` [Patch v2 23/28] OvmfPkg: " Judah Vang
2022-04-29 18:04 ` [Patch v2 24/28] OvmfPkg: Add ProtectedVariableLib reference Judah Vang
2022-04-29 18:04 ` [Patch v2 25/28] " Judah Vang
2022-04-29 18:04 ` [Patch v2 26/28] " Judah Vang
2022-04-29 18:04 ` [Patch v2 27/28] OvmfPkg: Add ProtectedVariable reference Judah Vang
2022-05-03  7:30   ` [edk2-devel] " Ard Biesheuvel
2022-04-29 18:04 ` [Patch v2 28/28] CryptoPkg: Enable cypto HMAC KDF library Judah Vang
2022-05-17  2:48 ` [edk2-devel] [Patch v2 00/28] UEFI variable protection Michael Kubacki
     [not found] ` <16EFC4965F71DFB8.20068@groups.io>
2022-06-16 19:13   ` Michael Kubacki
2022-08-23  3:35     ` Michael Kubacki

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