[PATCH v2 08/17] MdeModulePkg/VariableRuntimeDxe: implement standalone MM version

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

Reuse most of the existing code to implement a variable runtime
driver that will be able to execute in the context of standalone
MM.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
---
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf | 136 ++++++++++++++++++++
 MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.c   |  89 +++++++++++++
 2 files changed, 225 insertions(+)

diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf
new file mode 100644
index 000000000000..efb84ed87832
--- /dev/null
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf
@@ -0,0 +1,136 @@
+## @file
+#  Provides SMM variable service.
+#
+#  This module installs SMM variable protocol into SMM protocol database,
+#  which can be used by SMM driver, and installs SMM variable protocol
+#  into BS protocol database, which can be used to notify the SMM Runtime
+#  Dxe driver that the SMM variable service is ready.
+#  This module should be used with SMM Runtime DXE module together. The
+#  SMM Runtime DXE module would install variable arch protocol and variable
+#  write arch protocol based on SMM variable module.
+#
+#  Caution: This module requires additional review when modified.
+#  This driver will have external input - variable data and communicate buffer in SMM mode.
+#  This external input must be validated carefully to avoid security issues such as
+#  buffer overflow or integer overflow.
+#    The whole SMM authentication variable design relies on the integrity of flash part and SMM.
+#  which is assumed to be protected by platform.  All variable code and metadata in flash/SMM Memory
+#  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 - 2016, Intel Corporation. All rights reserved.<BR>
+# Copyright (c) 2018, Linaro, Ltd. All rights reserved.<BR>
+# This program and the accompanying materials
+# are licensed and made available under the terms and conditions of the BSD License
+# which accompanies this distribution. The full text of the license may be found at
+# http://opensource.org/licenses/bsd-license.php
+# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x0001001B
+  BASE_NAME                      = VariableStandaloneMm
+  FILE_GUID                      = 7ee2c0c1-c21a-4113-a53a-66824a95696f
+  MODULE_TYPE                    = MM_STANDALONE
+  VERSION_STRING                 = 1.0
+  PI_SPECIFICATION_VERSION       = 0x00010032
+  ENTRY_POINT                    = VariableServiceInitialize
+
+#
+# The following information is for reference only and not required by the build tools.
+#
+#  VALID_ARCHITECTURES           = IA32 X64 ARM AARCH64
+#
+
+
+[Sources]
+  Reclaim.c
+  Variable.c
+  VariableSmm.c
+  VariableStandaloneMm.c
+  VarCheck.c
+  Variable.h
+  PrivilegePolymorphic.h
+  VariableExLib.c
+  TcgMorLockSmm.c
+  SpeculationBarrierSmm.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+  StandaloneMmPkg/StandaloneMmPkg.dec
+
+[LibraryClasses]
+  AuthVariableLib
+  BaseLib
+  BaseMemoryLib
+  DebugLib
+  HobLib
+  MemoryAllocationLib
+  MmServicesTableLib
+  StandaloneMmDriverEntryPoint
+  SynchronizationLib
+  VarCheckLib
+
+[Protocols]
+  gEfiSmmFirmwareVolumeBlockProtocolGuid        ## CONSUMES
+  ## CONSUMES
+  ## NOTIFY
+  gEfiSmmFaultTolerantWriteProtocolGuid
+  ## PRODUCES
+  ## UNDEFINED # SmiHandlerRegister
+  gEfiSmmVariableProtocolGuid
+  gEfiMmEndOfDxeProtocolGuid                   ## NOTIFY
+  gEdkiiSmmVarCheckProtocolGuid                ## PRODUCES
+
+[Guids]
+  ## SOMETIMES_CONSUMES   ## GUID # Signature of Variable store header
+  ## SOMETIMES_PRODUCES   ## GUID # Signature of Variable store header
+  ## SOMETIMES_CONSUMES   ## HOB
+  ## SOMETIMES_PRODUCES   ## SystemTable
+  gEfiAuthenticatedVariableGuid
+
+  ## SOMETIMES_CONSUMES   ## GUID # Signature of Variable store header
+  ## SOMETIMES_PRODUCES   ## GUID # Signature of Variable store header
+  ## SOMETIMES_CONSUMES   ## HOB
+  ## SOMETIMES_PRODUCES   ## SystemTable
+  gEfiVariableGuid
+
+  ## SOMETIMES_CONSUMES   ## Variable:L"PlatformLang"
+  ## SOMETIMES_PRODUCES   ## Variable:L"PlatformLang"
+  ## SOMETIMES_CONSUMES   ## Variable:L"Lang"
+  ## SOMETIMES_PRODUCES   ## Variable:L"Lang"
+  gEfiGlobalVariableGuid
+
+  gEfiMemoryOverwriteControlDataGuid            ## SOMETIMES_CONSUMES   ## Variable:L"MemoryOverwriteRequestControl"
+  gEfiMemoryOverwriteRequestControlLockGuid     ## SOMETIMES_PRODUCES   ## Variable:L"MemoryOverwriteRequestControlLock"
+
+  gEfiSystemNvDataFvGuid                        ## CONSUMES             ## GUID
+  gEdkiiFaultTolerantWriteGuid                  ## SOMETIMES_CONSUMES   ## HOB
+
+  ## SOMETIMES_CONSUMES   ## Variable:L"VarErrorFlag"
+  ## SOMETIMES_PRODUCES   ## Variable:L"VarErrorFlag"
+  gEdkiiVarErrorFlagGuid
+
+[FixedPcd]
+  gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageVariableSize       ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageVariableBase       ## SOMETIMES_CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageVariableBase64     ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize                  ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxAuthVariableSize              ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVolatileVariableSize          ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxHardwareErrorVariableSize     ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdVariableStoreSize                ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHwErrStorageSize                 ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxUserNvVariableSpaceSize           ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdBoottimeReservedNvVariableSpaceSize  ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdReclaimVariableSpaceAtEndOfDxe   ## CONSUMES
+
+[FeaturePcd]
+  gEfiMdeModulePkgTokenSpaceGuid.PcdVariableCollectStatistics        ## CONSUMES  # statistic the information of variable.
+  gEfiMdePkgTokenSpaceGuid.PcdUefiVariableDefaultLangDeprecate       ## CONSUMES  # Auto update PlatformLang/Lang
+
+[Depex]
+  TRUE
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.c
new file mode 100644
index 000000000000..51e21c599560
--- /dev/null
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.c
@@ -0,0 +1,89 @@
+/** @file
+
+  Parts of the SMM/MM implementation that are specific to standalone MM
+
+Copyright (c) 2011 - 2018, Intel Corporation. All rights reserved. <BR>
+Copyright (c) 2018, Linaro, Ltd. All rights reserved. <BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "Variable.h"
+
+/**
+  This function checks if the buffer is valid per processor architecture and
+  does not overlap with SMRAM.
+
+  @param Buffer The buffer start address to be checked.
+  @param Length The buffer length to be checked.
+
+  @retval TRUE  This buffer is valid per processor architecture and does not
+                overlap with SMRAM.
+  @retval FALSE This buffer is not valid per processor architecture or overlaps
+                with SMRAM.
+**/
+BOOLEAN
+VariableSmmIsBufferOutsideSmmValid (
+  IN EFI_PHYSICAL_ADDRESS  Buffer,
+  IN UINT64                Length
+  )
+{
+  return TRUE;
+}
+
+/**
+  Notify the system that the SMM variable driver is ready
+**/
+VOID
+VariableNotifySmmReady (
+  VOID
+  )
+{
+}
+
+/**
+  Notify the system that the SMM variable write driver is ready
+**/
+VOID
+VariableNotifySmmWriteReady (
+  VOID
+  )
+{
+}
+
+/**
+  Variable service MM driver entry point
+**/
+EFI_STATUS
+EFIAPI
+VariableServiceInitialize (
+  IN EFI_HANDLE                           ImageHandle,
+  IN EFI_MM_SYSTEM_TABLE                  *MmSystemTable
+  )
+{
+  return MmVariableServiceInitialize ();
+}
+
+/**
+  Whether the TCG or TCG2 protocols are installed in the UEFI protocol database.
+  This information is used by the MorLock code to infer whether an existing
+  MOR variable is legitimate or not.
+
+  @retval TRUE  Either the TCG or TCG2 protocol is installed in the UEFI
+                protocol database
+  @retval FALSE Neither the TCG nor the TCG2 protocol is installed in the UEFI
+                protocol database
+**/
+BOOLEAN
+VariableHaveTcgProtocols (
+  VOID
+  )
+{
+  return FALSE;
+}
-- 
2.20.1