[PATCH RESEND v1 2/9] MdePkg/DrbgLib: Add NULL instance of Drbg Library

["PierreGondois" <pierre.gondois@arm.com>]

From: Pierre Gondois <Pierre.Gondois@arm.com>

Add a Null instance of the DrbgLib satisfy potential
build dependencies issues.

Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
---
 MdePkg/Library/DrbgLibNull/DrbgLib.c       | 165 +++++++++++++++++++++
 MdePkg/Library/DrbgLibNull/DrbgLibNull.inf |  21 +++
 MdePkg/MdePkg.dsc                          |   1 +
 3 files changed, 187 insertions(+)
 create mode 100644 MdePkg/Library/DrbgLibNull/DrbgLib.c
 create mode 100644 MdePkg/Library/DrbgLibNull/DrbgLibNull.inf

diff --git a/MdePkg/Library/DrbgLibNull/DrbgLib.c b/MdePkg/Library/DrbgLibNull/DrbgLib.c
new file mode 100644
index 000000000000..e366843b03f0
--- /dev/null
+++ b/MdePkg/Library/DrbgLibNull/DrbgLib.c
@@ -0,0 +1,165 @@
+/** @file
+  Drbg library.
+  Cf. [1] s9 DRBG Mechanism Functions
+
+  Copyright (c) 2022, Arm Limited. All rights reserved.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+  @par Reference(s):
+  - [1] NIST Special Publication 800-90A Revision 1, June 2015, Recommendation
+        for Random Number Generation Using Deterministic Random Bit Generators.
+        (https://csrc.nist.gov/publications/detail/sp/800-90a/rev-1/final)
+  - [2] NIST Special Publication 800-90B, Recommendation for the Entropy
+        Sources Used for Random Bit Generation.
+        (https://csrc.nist.gov/publications/detail/sp/800-90b/final)
+  - [3] (Second Draft) NIST Special Publication 800-90C, Recommendation for
+        Random Bit Generator (RBG) Constructions.
+        (https://csrc.nist.gov/publications/detail/sp/800-90c/draft)
+  - [4] NIST Special Publication 800-57 Part 1 Revision 5, May 2020,
+        Recommendation for Key Management:Part 1 - General.
+        (https://csrc.nist.gov/publications/detail/sp/800-57-part-1/rev-5/final)
+  - [5] Unified Extensible Firmware Interface (UEFI) Specification,
+        Version 2.8 Errata B, May 2020
+        (https://www.uefi.org/specifications)
+
+  @par Glossary:
+    - TRNG - True Random Number Generator
+    - Sec  - Security
+    - DRBG - Deterministic Random Bits Generator
+    - CTR  - Counter
+**/
+
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+#include <Library/DrbgLib.h>
+
+/** Reseed a DRBG instance.
+
+  Implementation of Reseed_function.
+  Cf. [1] s9.2 'Reseeding a DRBG Instantiation'
+
+  @param  [in] PredResRequest   Indicates whether prediction resistance
+                                is to be provided during the request.
+                                Might not be supported by all Drbgs.
+  @param  [in] AddInput         An optional additional input.
+                                Might not be supported by all Drbgs.
+  @param  [in] AddInputLen      Additional input length (in bits).
+                                Might not be supported by all Drbgs.
+  @param  [in, out] Handle  The Drbg handle.
+
+  @retval EFI_SUCCESS             Success.
+  @retval EFI_INVALID_PARAMETER   Invalid parameter.
+  @retval EFI_OUT_OF_RESOURCES    Out of resources.
+**/
+EFI_STATUS
+EFIAPI
+DrbgReseedFn (
+  IN        BOOLEAN  PredResRequest,
+  IN  CONST CHAR8    *AddInput,
+  IN        UINTN    AddInputLen,
+  IN  OUT   VOID     *Handle
+  )
+{
+  ASSERT (FALSE);
+  return EFI_UNSUPPORTED;
+}
+
+/** Create a Drbg instance.
+
+  Implementation of Instantiate_function.
+  Cf. [1] s9.1 Instantiating a DRBG
+
+  @param  [in] DrbgMechanism    DRBG mechanism chosen.
+  @param  [in] DrbgEntropySrc   Entropy source chosen.
+  @param  [in] ReqSecStrength   Requested security strength (in bits).
+                                The security strenght granted can be different.
+  @param  [in] PredRes          Prediction resistance flag.
+                                If relevant, instantiate a DRBG that supports
+                                prediction resistance.
+                                Might not be supported by all Drbgs.
+  @param  [in] PersStr          Personnalization string.
+                                Might not be supported by all Drbgs.
+  @param  [in] PersStrLen       Personnalization string length (in bits).
+                                Might not be supported by all Drbgs.
+  @param  [out] HandlePtr   Pointer containting the created Drbg handle.
+
+  @retval EFI_SUCCESS             Success.
+  @retval EFI_INVALID_PARAMETER   Invalid parameter.
+  @retval EFI_OUT_OF_RESOURCES    Out of resources.
+**/
+EFI_STATUS
+EFIAPI
+DrbgInstantiateFn (
+  IN        DRBG_MECHANISM    DrbgMechanism,
+  IN        DRBG_ENTROPY_SRC  DrbgEntropySrc,
+  IN        UINTN             ReqSecStrength,
+  IN        BOOLEAN           PredRes,
+  IN  CONST CHAR8             *PersStr,
+  IN        UINTN             PersStrLen,
+  OUT       VOID              **HandlePtr
+  )
+{
+  ASSERT (FALSE);
+  return EFI_UNSUPPORTED;
+}
+
+/** Generate a random number.
+
+  Implementation of Generate_function.
+  Cf. [1] s9.3.1 The Generate Function
+
+  @param  [in] ReqSecStrength   Requested security strength (in bits).
+                                If the DrbgHandle cannot satisfy the request,
+                                an error is returned.
+  @param  [in] PredResReq       Request prediction resistance.
+                                If the DrbgHandle cannot satisfy the request,
+                                an error is returned.
+  @param  [in] AddInput         Additional input.
+                                Might not be supported by all Drbgs.
+  @param  [in] AddInputLen      Additional input length (in bits).
+                                Might not be supported by all Drbgs.
+  @param  [in] ReqNbBits        Number of random bits requested.
+  @param  [in, out] OutBuffer   If success, contains the random bits.
+                                The buffer must be at least ReqNbBits bits
+                                long.
+  @param  [in, out] Handle  The Drbg handle.
+
+  @retval EFI_SUCCESS             Success.
+  @retval EFI_INVALID_PARAMETER   Invalid parameter.
+  @retval EFI_OUT_OF_RESOURCES    Out of resources.
+**/
+EFI_STATUS
+EFIAPI
+DrbgGenerateFn (
+  IN        UINTN    ReqSecStrength,
+  IN        BOOLEAN  PredResReq,
+  IN  CONST CHAR8    *AddInput,
+  IN        UINTN    AddInputLen,
+  IN        UINTN    ReqNbBits,
+  IN  OUT   UINT8    *OutBuffer,
+  IN  OUT   VOID     *Handle
+  )
+{
+  ASSERT (FALSE);
+  return EFI_UNSUPPORTED;
+}
+
+/** Remove a DRBG instance.
+
+  Implementation of Uninstantiate_function.
+  Cf. [1] s9.4 Removing a DRBG Instantiation
+
+  @param  [in, out] Handle    The Drbg handle.
+
+  @retval EFI_SUCCESS             Success.
+  @retval EFI_INVALID_PARAMETER   Invalid parameter.
+**/
+EFI_STATUS
+EFIAPI
+DrbgUninstantiateFn (
+  IN  OUT VOID  *Handle
+  )
+{
+  ASSERT (FALSE);
+  return EFI_UNSUPPORTED;
+}
diff --git a/MdePkg/Library/DrbgLibNull/DrbgLibNull.inf b/MdePkg/Library/DrbgLibNull/DrbgLibNull.inf
new file mode 100644
index 000000000000..6e17af4390fc
--- /dev/null
+++ b/MdePkg/Library/DrbgLibNull/DrbgLibNull.inf
@@ -0,0 +1,21 @@
+## @file
+#  Drbg Null library
+#
+#  Copyright (c) 2022, Arm Limited. All rights reserved.<BR>
+#
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+##
+
+[Defines]
+  INF_VERSION    = 0x0001001B
+  BASE_NAME      = DrbgLib
+  FILE_GUID      = B8A688E5-C31A-4CF8-9A76-B31211D292DE
+  VERSION_STRING = 1.0
+  MODULE_TYPE    = DXE_DRIVER
+  LIBRARY_CLASS  = DrbgLib
+
+[Sources]
+  DrbgLib.c
+
+[Packages]
+  MdePkg/MdePkg.dec
diff --git a/MdePkg/MdePkg.dsc b/MdePkg/MdePkg.dsc
index 726350c215e5..4820cecd0db8 100644
--- a/MdePkg/MdePkg.dsc
+++ b/MdePkg/MdePkg.dsc
@@ -69,6 +69,7 @@ [Components]
   MdePkg/Library/BaseRngLibTimerLib/BaseRngLibTimerLib.inf
   MdePkg/Library/BaseTrngLibNull/BaseTrngLibNull.inf
   MdePkg/Library/AesLibNull/AesLibNull.inf
+  MdePkg/Library/DrbgLibNull/DrbgLibNull.inf
 
   MdePkg/Library/BaseSerialPortLibNull/BaseSerialPortLibNull.inf
   MdePkg/Library/BaseSynchronizationLib/BaseSynchronizationLib.inf
-- 
2.25.1