MdePkg/Library/TdxLib/Rtmr.c

   1 /** @file
   2
   3   Extends one of the RTMR measurement registers in TDCS with the provided
   4   extension data in memory.
   5
   6   Copyright (c) 2020 - 2021, Intel Corporation. All rights reserved.<BR>
   7   SPDX-License-Identifier: BSD-2-Clause-Patent
   8
   9 **/
  10
  11 #include <Library/BaseLib.h>
  12 #include <Library/DebugLib.h>
  13 #include <Uefi/UefiBaseType.h>
  14 #include <Library/TdxLib.h>
  15 #include <Library/BaseMemoryLib.h>
  16 #include <IndustryStandard/Tpm20.h>
  17 #include <IndustryStandard/Tdx.h>
  18
  19 #define RTMR_COUNT            4
  20 #define TD_EXTEND_BUFFER_LEN  (64 + 48)
  21
  22 UINT8  mExtendBuffer[TD_EXTEND_BUFFER_LEN];
  23
  24 /**
  25   This function extends one of the RTMR measurement register
  26   in TDCS with the provided extension data in memory.
  27   RTMR extending supports SHA384 which length is 48 bytes.
  28
  29   @param[in]  Data      Point to the data to be extended
  30   @param[in]  DataLen   Length of the data. Must be 48
  31   @param[in]  Index     RTMR index
  32
  33   @return EFI_SUCCESS
  34   @return EFI_INVALID_PARAMETER
  35   @return EFI_DEVICE_ERROR
  36
  37 **/
  38 EFI_STATUS
  39 EFIAPI
  40 TdExtendRtmr (
  41   IN  UINT32  *Data,
  42   IN  UINT32  DataLen,
  43   IN  UINT8   Index
  44   )
  45 {
  46   EFI_STATUS  Status;
  47   UINT64      TdCallStatus;
  48   UINT8       *ExtendBuffer;
  49
  50   Status = EFI_SUCCESS;
  51
  52   ASSERT (Data != NULL);
  53   ASSERT (DataLen == SHA384_DIGEST_SIZE);
  54   ASSERT (Index >= 0 && Index < RTMR_COUNT);
  55
  56   if ((Data == NULL) || (DataLen != SHA384_DIGEST_SIZE) || (Index >= RTMR_COUNT)) {
  57     return EFI_INVALID_PARAMETER;
  58   }
  59
  60   // TD.RTMR.EXTEND requires 64B-aligned guest physical address of
  61   // 48B-extension data. We use ALIGN_POINTER(Pointer, 64) to get
  62   // the 64B-aligned guest physical address.
  63   ExtendBuffer = ALIGN_POINTER (mExtendBuffer, 64);
  64   ASSERT (((UINTN)ExtendBuffer & 0x3f) == 0);
  65
  66   ZeroMem (ExtendBuffer, SHA384_DIGEST_SIZE);
  67   CopyMem (ExtendBuffer, Data, SHA384_DIGEST_SIZE);
  68
  69   TdCallStatus = TdCall (TDCALL_TDEXTENDRTMR, (UINT64)(UINTN)ExtendBuffer, Index, 0, 0);
  70
  71   if (TdCallStatus == TDX_EXIT_REASON_SUCCESS) {
  72     Status = EFI_SUCCESS;
  73   } else if (TdCallStatus == TDX_EXIT_REASON_OPERAND_INVALID) {
  74     Status = EFI_INVALID_PARAMETER;
  75   } else {
  76     Status = EFI_DEVICE_ERROR;
  77   }
  78
  79   if (Status != EFI_SUCCESS) {
  80     DEBUG ((DEBUG_ERROR, "Error returned from TdExtendRtmr call - 0x%lx\n", TdCallStatus));
  81   }
  82
  83   return Status;
  84 }