OvmfPkg/IntelTdx/TdxHelperLib/TdxHelperNull.c

   1 /** @file
   2   NULL instance of TdxHelperLib
   3
   4   Copyright (c) 2022 - 2023, Intel Corporation. All rights reserved.<BR>
   5
   6   SPDX-License-Identifier: BSD-2-Clause-Patent
   7
   8 **/
   9
  10 #include <Base.h>
  11 #include <PiPei.h>
  12
  13 /**
  14   In Tdx guest, some information need to be passed from host VMM to guest
  15   firmware. For example, the memory resource, etc. These information are
  16   prepared by host VMM and put in TdHob which is described in TdxMetadata.
  17   TDVF processes the TdHob to accept memories.
  18
  19   @retval   EFI_SUCCESS   Successfully process the TdHob
  20   @retval   Others        Other error as indicated
  21 **/
  22 EFI_STATUS
  23 EFIAPI
  24 TdxHelperProcessTdHob (
  25   VOID
  26   )
  27 {
  28   return EFI_UNSUPPORTED;
  29 }
  30
  31 /**
  32   In Tdx guest, TdHob is passed from host VMM to guest firmware and it contains
  33   the information of the memory resource. From the security perspective before
  34   it is consumed, it should be measured and extended.
  35  *
  36  * @retval EFI_SUCCESS Successfully measure the TdHob
  37  * @retval Others      Other error as indicated
  38  */
  39 EFI_STATUS
  40 EFIAPI
  41 TdxHelperMeasureTdHob (
  42   VOID
  43   )
  44 {
  45   return EFI_UNSUPPORTED;
  46 }
  47
  48 /**
  49  * In Tdx guest, Configuration FV (CFV) is treated as external input because it
  50  * may contain the data provided by VMM. From the sucurity perspective Cfv image
  51  * should be measured before it is consumed.
  52  *
  53  * @retval EFI_SUCCESS Successfully measure the CFV image
  54  * @retval Others      Other error as indicated
  55  */
  56 EFI_STATUS
  57 EFIAPI
  58 TdxHelperMeasureCfvImage (
  59   VOID
  60   )
  61 {
  62   return EFI_UNSUPPORTED;
  63 }
  64
  65 /**
  66   Build the GuidHob for tdx measurements which were done in SEC phase.
  67   The measurement values are stored in WorkArea.
  68
  69   @retval EFI_SUCCESS  The GuidHob is built successfully
  70   @retval Others       Other errors as indicated
  71 **/
  72 EFI_STATUS
  73 EFIAPI
  74 TdxHelperBuildGuidHobForTdxMeasurement (
  75   VOID
  76   )
  77 {
  78   return EFI_UNSUPPORTED;
  79 }