SecurityPkg/Library/PeiTcg2PhysicalPresenceLib/PeiTcg2PhysicalPresenceLib.c

   1 /** @file
   2   Get TPM 2.0 physical presence information.
   3
   4   This library will get TPM 2.0 physical presence information.
   5
   6 Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
   7 This program and the accompanying materials
   8 are licensed and made available under the terms and conditions of the BSD License
   9 which accompanies this distribution.  The full text of the license may be found at
  10 http://opensource.org/licenses/bsd-license.php
  11
  12 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15 **/
  16
  17 #include <PiPei.h>
  18
  19 #include <Guid/Tcg2PhysicalPresenceData.h>
  20 #include <Ppi/ReadOnlyVariable2.h>
  21
  22 #include <Library/DebugLib.h>
  23 #include <Library/PeiServicesLib.h>
  24 #include <Library/PeiServicesTablePointerLib.h>
  25 #include <Library/Tcg2PhysicalPresenceLib.h>
  26
  27 /**
  28   Return TPM2 ManagementFlags set by PP interface.
  29
  30   @retval    ManagementFlags    TPM2 Management Flags.
  31 **/
  32 UINT32
  33 EFIAPI
  34 Tcg2PhysicalPresenceLibGetManagementFlags (
  35   VOID
  36   )
  37 {
  38   EFI_STATUS                        Status;
  39   EFI_PEI_READ_ONLY_VARIABLE2_PPI   *VariablePpi;
  40   EFI_TCG2_PHYSICAL_PRESENCE_FLAGS  PpiFlags;
  41   UINTN                             DataSize;
  42
  43   Status = PeiServicesLocatePpi (&gEfiPeiReadOnlyVariable2PpiGuid, 0, NULL, (VOID **) &VariablePpi);
  44   ASSERT_EFI_ERROR (Status);
  45
  46   DataSize = sizeof (EFI_TCG2_PHYSICAL_PRESENCE_FLAGS);
  47   Status = VariablePpi->GetVariable (
  48                           VariablePpi,
  49                           TCG2_PHYSICAL_PRESENCE_FLAGS_VARIABLE,
  50                           &gEfiTcg2PhysicalPresenceGuid,
  51                           NULL,
  52                           &DataSize,
  53                           &PpiFlags
  54                           );
  55   if (EFI_ERROR (Status)) {
  56     PpiFlags.PPFlags = TCG2_BIOS_TPM_MANAGEMENT_FLAG_DEFAULT;
  57   }
  58   return PpiFlags.PPFlags;
  59 }