Re: [edk2-devel] [PATCH 06/11] SecurityPkg/DxeRngLibRngProtocol: add RNG protocol version of RngLib

["Laszlo Ersek" <lersek@redhat.com>]

On 11/14/19 03:17, Wang, Jian J wrote:
> From: Matthew Carlson <macarl@microsoft.com>
> 
> This version of RngLib makes use of EFI_RNG_PROTOCOL to provide random
> number. According to UEFI spec, EFI_RNG_PROTOCOL should meet NIST SP
> 800-90 and/or ANSI X9.31 standards.

I'd like to slightly correct the UEFI spec reference. In UEFI-2.8,
section "37.5.1 EFI RNG Algorithm Definitions" writes,

    [...] The algorithms listed are optional, not meant to be exhaustive
    and may be augmented by vendors or other industry standards. [...]

Meaning that an EFI_RNG_PROTOCOL instance is not "required", per spec,
to support any one of the
- gEfiRngAlgorithmSp80090Ctr256Guid
- gEfiRngAlgorithmSp80090Hmac256Guid
- gEfiRngAlgorithmSp80090Hash256Guid
algorithms.

It's of course fine to require one of those algorithms, as a policy
decision, in this particular library instance -- but, as far as I can
tell, that decision does not follow from the spec.

Thanks
Laszlo

> 
> Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1871
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Chao Zhang <chao.b.zhang@intel.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> Cc: Matthew Carlson <macarl@microsoft.com>
> Cc: Sean Brogan <sean.brogan@microsoft.com>
> Cc: Bret Barkelew <bret.barkelew@microsoft.com>
> Cc: Liming Gao <liming.gao@intel.com>
> Cc: Ray Ni <ray.ni@intel.com>
> Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
> ---
>  .../DxeRngLibRngProtocol.c                    | 200 ++++++++++++++++++
>  .../DxeRngLibRngProtocol.inf                  |  42 ++++
>  .../DxeRngLibRngProtocol.uni                  |  14 ++
>  3 files changed, 256 insertions(+)
>  create mode 100644 SecurityPkg/RandomNumberGenerator/DxeRngLibRngProtocol/DxeRngLibRngProtocol.c
>  create mode 100644 SecurityPkg/RandomNumberGenerator/DxeRngLibRngProtocol/DxeRngLibRngProtocol.inf
>  create mode 100644 SecurityPkg/RandomNumberGenerator/DxeRngLibRngProtocol/DxeRngLibRngProtocol.uni
> 
> diff --git a/SecurityPkg/RandomNumberGenerator/DxeRngLibRngProtocol/DxeRngLibRngProtocol.c b/SecurityPkg/RandomNumberGenerator/DxeRngLibRngProtocol/DxeRngLibRngProtocol.c
> new file mode 100644
> index 0000000000..8ce4a7050d
> --- /dev/null
> +++ b/SecurityPkg/RandomNumberGenerator/DxeRngLibRngProtocol/DxeRngLibRngProtocol.c
> @@ -0,0 +1,200 @@
> +/** @file
> + Provides an implementation of the library class RngLib that uses the Rng protocol.
> +
> +Copyright (c) Microsoft Corporation. All rights reserved.
> +Copyright (c) 2019, Intel Corporation. All rights reserved.
> +SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +#include <Uefi.h>
> +#include <Library/UefiBootServicesTableLib.h>
> +#include <Library/DebugLib.h>
> +#include <Library/RngLib.h>
> +#include <Protocol/Rng.h>
> +
> +/**
> +  Generates a random number via the NIST 800-9A algorithm.  Refer to
> +  http://csrc.nist.gov/groups/STM/cavp/documents/drbg/DRBGVS.pdf
> +  for more information.
> +
> +  @param[out] Buffer      Buffer to receive the random number.
> +  @param[in]  BufferSize  Number of bytes in Buffer.
> +
> +  @retval EFI_SUCCESS  Random data generated successfully.
> +  @retval Others       Failed to generate the random number.
> +
> +**/
> +STATIC
> +EFI_STATUS
> +GenerateRandomNumberViaNist800Algorithm(
> +  OUT UINT8* Buffer,
> +  IN  UINTN  BufferSize
> +  )
> +{
> +  EFI_STATUS        Status;
> +  EFI_RNG_PROTOCOL* RngProtocol;
> +
> +  Status = EFI_UNSUPPORTED;
> +  RngProtocol = NULL;
> +
> +  if (Buffer == NULL) {
> +    DEBUG ((DEBUG_ERROR, "[%a] Buffer == NULL.\n", __FUNCTION__));
> +    return EFI_INVALID_PARAMETER;
> +  }
> +
> +  if (gBS == NULL) {
> +    DEBUG ((DEBUG_ERROR, "[%a] GenerateRandomNumber, gBS == NULL.  Called too soon.\n", __FUNCTION__));
> +    return EFI_LOAD_ERROR;
> +  }
> +
> +  Status = gBS->LocateProtocol (&gEfiRngProtocolGuid, NULL, (VOID **)&RngProtocol);
> +  if (EFI_ERROR (Status) || RngProtocol == NULL) {
> +    DEBUG ((DEBUG_ERROR, "[%a] Could not locate RNG prototocol, Status = %r\n", __FUNCTION__, Status));
> +    return Status;
> +  }
> +
> +  Status = RngProtocol->GetRNG (RngProtocol, &gEfiRngAlgorithmSp80090Ctr256Guid, BufferSize, Buffer);
> +  DEBUG ((DEBUG_VERBOSE, "[%a] GetRNG algorithm CTR-256 - Status = %r\n", __FUNCTION__, Status));
> +  if (!EFI_ERROR (Status)) {
> +    return Status;
> +  }
> +
> +  Status = RngProtocol->GetRNG (RngProtocol, &gEfiRngAlgorithmSp80090Hmac256Guid, BufferSize, Buffer);
> +  DEBUG ((DEBUG_VERBOSE, "[%a] GetRNG algorithm HMAC-256 - Status = %r\n", __FUNCTION__, Status));
> +  if (!EFI_ERROR (Status)) {
> +    return Status;
> +  }
> +
> +  Status = RngProtocol->GetRNG (RngProtocol, &gEfiRngAlgorithmSp80090Hash256Guid, BufferSize, Buffer);
> +  DEBUG ((DEBUG_VERBOSE, "[%a] GetRNG algorithm Hash-256 - Status = %r\n", __FUNCTION__, Status));
> +  if (!EFI_ERROR (Status)) {
> +    return Status;
> +  }
> +  //
> +  // If we get to this point, we have failed
> +  //
> +  DEBUG((DEBUG_ERROR, "[%a] GetRNG() failed, staus = %r\n", __FUNCTION__, Status));
> +
> +  return Status;
> +}
> +
> +
> +/**
> +  Generates a 16-bit random number.
> +
> +  if Rand is NULL, return FALSE.
> +
> +  @param[out] Rand     Buffer pointer to store the 16-bit random value.
> +
> +  @retval TRUE         Random number generated successfully.
> +  @retval FALSE        Failed to generate the random number.
> +
> +**/
> +BOOLEAN
> +EFIAPI
> +GetRandomNumber16 (
> +  OUT     UINT16                    *Rand
> +  )
> +{
> +  EFI_STATUS Status;
> +
> +  if (Rand == NULL) {
> +    return FALSE;
> +  }
> +
> +  Status = GenerateRandomNumberViaNist800Algorithm ((UINT8 *)Rand, 2);
> +  if (EFI_ERROR (Status)) {
> +    return FALSE;
> +  }
> +  return TRUE;
> +}
> +
> +/**
> +  Generates a 32-bit random number.
> +
> +  if Rand is NULL, return FALSE.
> +
> +  @param[out] Rand     Buffer pointer to store the 32-bit random value.
> +
> +  @retval TRUE         Random number generated successfully.
> +  @retval FALSE        Failed to generate the random number.
> +
> +**/
> +BOOLEAN
> +EFIAPI
> +GetRandomNumber32 (
> +  OUT     UINT32                    *Rand
> +  )
> +{
> +  EFI_STATUS Status;
> +
> +  if (Rand == NULL) {
> +    return FALSE;
> +  }
> +
> +  Status = GenerateRandomNumberViaNist800Algorithm ((UINT8 *)Rand, 4);
> +  if (EFI_ERROR (Status)) {
> +    return FALSE;
> +  }
> +  return TRUE;
> +}
> +
> +/**
> +  Generates a 64-bit random number.
> +
> +  if Rand is NULL, return FALSE.
> +
> +  @param[out] Rand     Buffer pointer to store the 64-bit random value.
> +
> +  @retval TRUE         Random number generated successfully.
> +  @retval FALSE        Failed to generate the random number.
> +
> +**/
> +BOOLEAN
> +EFIAPI
> +GetRandomNumber64 (
> +  OUT     UINT64                    *Rand
> +  )
> +{
> +  EFI_STATUS Status;
> +
> +  if (Rand == NULL) {
> +    return FALSE;
> +  }
> +
> +  Status = GenerateRandomNumberViaNist800Algorithm ((UINT8 *)Rand, 8);
> +  if (EFI_ERROR (Status)) {
> +    return FALSE;
> +  }
> +  return TRUE;
> +}
> +
> +/**
> +  Generates a 128-bit random number.
> +
> +  if Rand is NULL, return FALSE.
> +
> +  @param[out] Rand     Buffer pointer to store the 128-bit random value.
> +
> +  @retval TRUE         Random number generated successfully.
> +  @retval FALSE        Failed to generate the random number.
> +
> +**/
> +BOOLEAN
> +EFIAPI
> +GetRandomNumber128 (
> +  OUT     UINT64                    *Rand
> +  )
> +{
> +  EFI_STATUS Status;
> +
> +  if (Rand == NULL) {
> +    return FALSE;
> +  }
> +
> +  Status = GenerateRandomNumberViaNist800Algorithm ((UINT8 *)Rand, 16);
> +  if (EFI_ERROR (Status)) {
> +    return FALSE;
> +  }
> +  return TRUE;
> +}
> diff --git a/SecurityPkg/RandomNumberGenerator/DxeRngLibRngProtocol/DxeRngLibRngProtocol.inf b/SecurityPkg/RandomNumberGenerator/DxeRngLibRngProtocol/DxeRngLibRngProtocol.inf
> new file mode 100644
> index 0000000000..d47fe3be53
> --- /dev/null
> +++ b/SecurityPkg/RandomNumberGenerator/DxeRngLibRngProtocol/DxeRngLibRngProtocol.inf
> @@ -0,0 +1,42 @@
> +# @file
> +# Provides implementation of the library class RngLib that uses the RngProtocol
> +#
> +# @copyright
> +# Copyright (c) Microsoft Corporation. All rights reserved.
> +# SPDX-License-Identifier: BSD-2-Clause-Patent
> +#
> +##
> +
> +[Defines]
> +  INF_VERSION     = 0x00010029
> +  BASE_NAME       = DxeRngLibRngProtocol
> +  MODULE_UNI_FILE = DxeRngLibRngProtocol.uni
> +  FILE_GUID       = FF9F84C5-A33E-44E3-9BB5-0D654B2D4149
> +  MODULE_TYPE     = DXE_DRIVER
> +  VERSION_STRING  = 1.0
> +  LIBRARY_CLASS   = RngLib|DXE_DRIVER DXE_RUNTIME_DRIVER DXE_SMM_DRIVER UEFI_APPLICATION UEFI_DRIVER
> +
> +#
> +#  VALID_ARCHITECTURES           = IA32 X64 EBC ARM AARCH64
> +#
> +
> +[Packages]
> +  MdePkg/MdePkg.dec
> +
> +[Sources]
> +  DxeRngLibRngProtocol.c
> +
> +[LibraryClasses]
> +  DebugLib
> +  UefiBootServicesTableLib
> +
> +[Protocols]
> +  gEfiRngProtocolGuid                 ## CONSUMES
> +
> +[Depex]
> +  gEfiRngProtocolGuid
> +
> +[Guids]
> +  gEfiRngAlgorithmSp80090Ctr256Guid            ## CONSUMES
> +  gEfiRngAlgorithmSp80090Hash256Guid           ## CONSUMES
> +  gEfiRngAlgorithmSp80090Hmac256Guid           ## CONSUMES
> diff --git a/SecurityPkg/RandomNumberGenerator/DxeRngLibRngProtocol/DxeRngLibRngProtocol.uni b/SecurityPkg/RandomNumberGenerator/DxeRngLibRngProtocol/DxeRngLibRngProtocol.uni
> new file mode 100644
> index 0000000000..09af056bd3
> --- /dev/null
> +++ b/SecurityPkg/RandomNumberGenerator/DxeRngLibRngProtocol/DxeRngLibRngProtocol.uni
> @@ -0,0 +1,14 @@
> +// /** @file
> +// Instance of RNG (Random Number Generator) Library Based on EFI_RNG_PROTOCOL.
> +//
> +// Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
> +//
> +// SPDX-License-Identifier: BSD-2-Clause-Patent
> +//
> +// **/
> +
> +
> +#string STR_MODULE_ABSTRACT             #language en-US "Instance of RNG Library Based on EFI_RNG_PROTOCOL."
> +
> +#string STR_MODULE_DESCRIPTION          #language en-US "This version of RNG library makes use of EFI_RNG_PROTOCOL to generate random number compliant with NIST 800-9A."
> +
>