From ef4cf3d88df2dd2b8afa790007c9f62a3d6cfcd6 Mon Sep 17 00:00:00 2001 From: Sami Mujawar Date: Fri, 28 Oct 2022 17:32:47 +0200 Subject: MdePkg/ArmTrngLib: Add NULL instance of Arm TRNG Library Bugzilla: 3668 (https://bugzilla.tianocore.org/show_bug.cgi?id=3668) The Arm True Random Number Generator (TRNG) library defines an interface to access the entropy source on a platform. On platforms that do not have access to an entropy source, a NULL instance of the TRNG library may be useful to satisfy the build dependency. Therefore, add a NULL instance of the Arm TRNG library. Signed-off-by: Pierre Gondois Reviewed-by: Liming Gao --- .../BaseArmTrngLibNull/BaseArmTrngLibNull.c | 121 +++++++++++++++++++++ .../BaseArmTrngLibNull/BaseArmTrngLibNull.inf | 30 +++++ .../BaseArmTrngLibNull/BaseArmTrngLibNull.uni | 12 ++ MdePkg/MdeLibs.dsc.inc | 1 + MdePkg/MdePkg.dsc | 1 + 5 files changed, 165 insertions(+) create mode 100644 MdePkg/Library/BaseArmTrngLibNull/BaseArmTrngLibNull.c create mode 100644 MdePkg/Library/BaseArmTrngLibNull/BaseArmTrngLibNull.inf create mode 100644 MdePkg/Library/BaseArmTrngLibNull/BaseArmTrngLibNull.uni diff --git a/MdePkg/Library/BaseArmTrngLibNull/BaseArmTrngLibNull.c b/MdePkg/Library/BaseArmTrngLibNull/BaseArmTrngLibNull.c new file mode 100644 index 0000000000..316d78bf5e --- /dev/null +++ b/MdePkg/Library/BaseArmTrngLibNull/BaseArmTrngLibNull.c @@ -0,0 +1,121 @@ +/** @file + Null version of the Arm TRNG (True Random Number Generator) services + (Cf [1]). + + Copyright (c) 2021 - 2022, Arm Limited. All rights reserved.
+ + SPDX-License-Identifier: BSD-2-Clause-Patent + + @par Reference(s): + - [1] Arm True Random Number Generator Firmware, Interface 1.0, + Platform Design Document. + (https://developer.arm.com/documentation/den0098/latest/) + - [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) + + @par Glossary: + - TRNG - True Random Number Generator +**/ + +#include +#include + +/** Get the version of the Arm TRNG backend. + + A TRNG may be implemented by the system firmware, in which case this + function shall return the version of the Arm TRNG backend. + The implementation must return NOT_SUPPORTED if a Back end is not present. + + @param [out] MajorRevision Major revision. + @param [out] MinorRevision Minor revision. + + @retval RETURN_SUCCESS The function completed successfully. + @retval RETURN_INVALID_PARAMETER Invalid parameter. + @retval RETURN_UNSUPPORTED Backend not present. +**/ +RETURN_STATUS +EFIAPI +GetArmTrngVersion ( + OUT UINT16 *MajorRevision, + OUT UINT16 *MinorRevision + ) +{ + ASSERT (FALSE); + return RETURN_UNSUPPORTED; +} + +/** Get the UUID of the Arm TRNG backend. + + A TRNG may be implemented by the system firmware, in which case this + function shall return the UUID of the TRNG backend. + Returning the Arm TRNG UUID is optional and if not implemented, + RETURN_UNSUPPORTED shall be returned. + + Note: The caller must not rely on the returned UUID as a trustworthy Arm TRNG + Back end identity + + @param [out] Guid UUID of the Arm TRNG backend. + + @retval RETURN_SUCCESS The function completed successfully. + @retval RETURN_INVALID_PARAMETER Invalid parameter. + @retval RETURN_UNSUPPORTED Function not implemented. +**/ +RETURN_STATUS +EFIAPI +GetArmTrngUuid ( + OUT GUID *Guid + ) +{ + ASSERT (FALSE); + return RETURN_UNSUPPORTED; +} + +/** Returns maximum number of entropy bits that can be returned in a single + call. + + @return Returns the maximum number of Entropy bits that can be returned + in a single call to GetArmTrngEntropy(). +**/ +UINTN +EFIAPI +GetArmTrngMaxSupportedEntropyBits ( + VOID + ) +{ + ASSERT (FALSE); + return 0; +} + +/** Returns N bits of conditioned entropy. + + See [2] Section 2.3.1 GetEntropy: An Interface to the Entropy Source + GetEntropy + Input: + bits_of_entropy: the requested amount of entropy + Output: + entropy_bitstring: The string that provides the requested entropy. + status: A Boolean value that is TRUE if the request has been satisfied, + and is FALSE otherwise. + + @param [in] EntropyBits Number of entropy bits requested. + @param [in] BufferSize Size of the Buffer in bytes. + @param [out] Buffer Buffer to return the entropy bits. + + @retval RETURN_SUCCESS The function completed successfully. + @retval RETURN_INVALID_PARAMETER Invalid parameter. + @retval RETURN_UNSUPPORTED Function not implemented. + @retval RETURN_BAD_BUFFER_SIZE Buffer size is too small. + @retval RETURN_NOT_READY No Entropy available. +**/ +RETURN_STATUS +EFIAPI +GetArmTrngEntropy ( + IN UINTN EntropyBits, + IN UINTN BufferSize, + OUT UINT8 *Buffer + ) +{ + ASSERT (FALSE); + return RETURN_UNSUPPORTED; +} diff --git a/MdePkg/Library/BaseArmTrngLibNull/BaseArmTrngLibNull.inf b/MdePkg/Library/BaseArmTrngLibNull/BaseArmTrngLibNull.inf new file mode 100644 index 0000000000..256df1373e --- /dev/null +++ b/MdePkg/Library/BaseArmTrngLibNull/BaseArmTrngLibNull.inf @@ -0,0 +1,30 @@ +## @file +# Null instance of the Arm TRNG (True Random Number Generator) Library. +# +# Copyright (c) 2021 - 2022, Arm Limited. All rights reserved.
+# +# SPDX-License-Identifier: BSD-2-Clause-Patent +# +## + +[Defines] + INF_VERSION = 1.29 + BASE_NAME = BaseArmTrngLibNull + MODULE_UNI_FILE = BaseArmTrngLibNull.uni + FILE_GUID = ABDE1C87-4F50-4B82-9133-7A79E13F69AB + MODULE_TYPE = BASE + VERSION_STRING = 1.0 + LIBRARY_CLASS = ArmTrngLib + +# +# VALID_ARCHITECTURES = IA32 X64 ARM AARCH64 RISCV64 +# + +[Sources] + BaseArmTrngLibNull.c + +[Packages] + MdePkg/MdePkg.dec + +[LibraryClasses] + DebugLib diff --git a/MdePkg/Library/BaseArmTrngLibNull/BaseArmTrngLibNull.uni b/MdePkg/Library/BaseArmTrngLibNull/BaseArmTrngLibNull.uni new file mode 100644 index 0000000000..876764b8be --- /dev/null +++ b/MdePkg/Library/BaseArmTrngLibNull/BaseArmTrngLibNull.uni @@ -0,0 +1,12 @@ +// /** @file +// Null Instance of the Arm TRNG (True Random Number Generator) Library. +// +// Copyright (c) 2021 - 2022, Arm Limited. All rights reserved.
+// +// SPDX-License-Identifier: BSD-2-Clause-Patent +// +// **/ + +#string STR_MODULE_ABSTRACT #language en-US "Null instance of TRNG Library" + +#string STR_MODULE_DESCRIPTION #language en-US "This library instance should be used with modules that inherit an (indirect) dependency on the ArmTrngLib class, but never actually call ArmTrngLib APIs for consuming Entropy." diff --git a/MdePkg/MdeLibs.dsc.inc b/MdePkg/MdeLibs.dsc.inc index fc6f385b30..4580481cb5 100644 --- a/MdePkg/MdeLibs.dsc.inc +++ b/MdePkg/MdeLibs.dsc.inc @@ -12,6 +12,7 @@ ## [LibraryClasses] + ArmTrngLib|MdePkg/Library/BaseArmTrngLibNull/BaseArmTrngLibNull.inf RegisterFilterLib|MdePkg/Library/RegisterFilterLibNull/RegisterFilterLibNull.inf CpuLib|MdePkg/Library/BaseCpuLib/BaseCpuLib.inf SmmCpuRendezvousLib|MdePkg/Library/SmmCpuRendezvousLibNull/SmmCpuRendezvousLibNull.inf diff --git a/MdePkg/MdePkg.dsc b/MdePkg/MdePkg.dsc index 493a13ec91..32a852dc46 100644 --- a/MdePkg/MdePkg.dsc +++ b/MdePkg/MdePkg.dsc @@ -57,6 +57,7 @@ MdePkg/Library/PciSegmentLibSegmentInfo/BasePciSegmentLibSegmentInfo.inf MdePkg/Library/PciSegmentLibSegmentInfo/DxeRuntimePciSegmentLibSegmentInfo.inf MdePkg/Library/BaseS3PciSegmentLib/BaseS3PciSegmentLib.inf + MdePkg/Library/BaseArmTrngLibNull/BaseArmTrngLibNull.inf MdePkg/Library/BasePeCoffGetEntryPointLib/BasePeCoffGetEntryPointLib.inf MdePkg/Library/BasePeCoffLib/BasePeCoffLib.inf MdePkg/Library/BasePeCoffExtraActionLibNull/BasePeCoffExtraActionLibNull.inf -- cgit v1.2.3