CryptoPkg/Library/BaseCryptLibOnProtocolPpi/SmmCryptLib.c

   1 /** @file
   2   Implements the GetCryptoServices() API that retuns a pointer to the EDK II
   3   SMM Crypto Protocol.
   4
   5   Copyright (C) Microsoft Corporation. All rights reserved.
   6   SPDX-License-Identifier: BSD-2-Clause-Patent
   7
   8 **/
   9
  10 #include <PiSmm.h>
  11 #include <Library/BaseLib.h>
  12 #include <Library/DebugLib.h>
  13 #include <Library/SmmServicesTableLib.h>
  14 #include <Protocol/SmmCrypto.h>
  15
  16 EDKII_SMM_CRYPTO_PROTOCOL  *mSmmCryptoProtocol = NULL;
  17
  18 /**
  19   Internal worker function that returns the pointer to an EDK II Crypto
  20   Protocol/PPI.  The layout of the PPI, DXE Protocol, and SMM Protocol are
  21   identical which allows the implementation of the BaseCryptLib functions that
  22   call through a Protocol/PPI to be shared for the PEI, DXE, and SMM
  23   implementations.
  24
  25   This SMM implementation returns the pointer to the EDK II SMM Crypto Protocol
  26   that was found in the library constructor SmmCryptLibConstructor().
  27 **/
  28 VOID *
  29 GetCryptoServices (
  30   VOID
  31   )
  32 {
  33   return (VOID *)mSmmCryptoProtocol;
  34 }
  35
  36 /**
  37   Constructor looks up the EDK II SMM Crypto Protocol and verifies that it is
  38   not NULL and has a high enough version value to support all the BaseCryptLib
  39   functions.
  40
  41   @param  ImageHandle   The firmware allocated handle for the EFI image.
  42   @param  SystemTable   A pointer to the EFI System Table.
  43
  44   @retval  EFI_SUCCESS    The EDK II SMM Crypto Protocol was found.
  45   @retval  EFI_NOT_FOUND  The EDK II SMM Crypto Protocol was not found.
  46 **/
  47 EFI_STATUS
  48 EFIAPI
  49 SmmCryptLibConstructor (
  50   IN EFI_HANDLE        ImageHandle,
  51   IN EFI_SYSTEM_TABLE  *SystemTable
  52   )
  53 {
  54   EFI_STATUS  Status;
  55   UINTN       Version;
  56
  57   Status = gSmst->SmmLocateProtocol (
  58                     &gEdkiiSmmCryptoProtocolGuid,
  59                     NULL,
  60                     (VOID **)&mSmmCryptoProtocol
  61                     );
  62   if (EFI_ERROR (Status) || mSmmCryptoProtocol == NULL) {
  63     DEBUG((DEBUG_ERROR, "[SmmCryptLib] Failed to locate Crypto SMM Protocol. Status = %r\n", Status));
  64     ASSERT_EFI_ERROR (Status);
  65     ASSERT (mSmmCryptoProtocol != NULL);
  66     mSmmCryptoProtocol = NULL;
  67     return EFI_NOT_FOUND;
  68   }
  69
  70   Version = mSmmCryptoProtocol->GetVersion ();
  71   if (Version < EDKII_CRYPTO_VERSION) {
  72     DEBUG((DEBUG_ERROR, "[SmmCryptLib] Crypto SMM Protocol unsupported version %d\n", Version));
  73     ASSERT (Version >= EDKII_CRYPTO_VERSION);
  74     mSmmCryptoProtocol = NULL;
  75     return EFI_NOT_FOUND;
  76   }
  77
  78   return EFI_SUCCESS;
  79 }