[mirror_edk2.git] / FmpDevicePkg / FmpDxe / VariableSupport.c

/** @file\r
  UEFI variable support functions for Firmware Management Protocol based\r
  firmware updates.\r
\r
  Copyright (c) 2016, Microsoft Corporation. All rights reserved.<BR>\r
  Copyright (c) 2018 - 2021, Intel Corporation. All rights reserved.<BR>\r
\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include "FmpDxe.h"\r
#include "VariableSupport.h"\r
\r
/**\r
  Retrieve the value of a 32-bit UEFI Variable specified by VariableName and\r
  a GUID of gEfiCallerIdGuid.\r
\r
  @param[in]  VariableName  Pointer to the UEFI Variable name to retrieve.\r
  @param[out] Valid         Set to TRUE if UEFI Variable is present and the size\r
                            of the UEFI Variable value is 32-bits.  Otherwise\r
                            FALSE.\r
  @param[out] Value         If Valid is set to TRUE, then the 32-bit value of\r
                            the UEFI Variable.  Otherwise 0.\r
**/\r
static\r
VOID\r
GetFmpVariable (\r
  IN  CHAR16   *VariableName,\r
  OUT BOOLEAN  *Valid,\r
  OUT UINT32   *Value\r
  )\r
{\r
  EFI_STATUS  Status;\r
  UINTN       Size;\r
  UINT32      *Buffer;\r
\r
  *Valid = FALSE;\r
  *Value = 0;\r
  Size   = 0;\r
  Buffer = NULL;\r
  Status = GetVariable2 (\r
             VariableName,\r
             &gEfiCallerIdGuid,\r
             (VOID **)&Buffer,\r
             &Size\r
             );\r
  if (!EFI_ERROR (Status) && (Size == sizeof (*Value)) && (Buffer != NULL)) {\r
    *Valid = TRUE;\r
    *Value = *Buffer;\r
  }\r
\r
  if (Buffer != NULL) {\r
    FreePool (Buffer);\r
  }\r
}\r
\r
/**\r
  Delete the UEFI Variable with name specified by VariableName and GUID of\r
  gEfiCallerIdGuid.  If the variable can not be deleted, then print a\r
  DEBUG_ERROR message.\r
\r
  @param[in] VariableName  Pointer to the UEFI Variable name to delete.\r
**/\r
static\r
VOID\r
DeleteFmpVariable (\r
  IN CHAR16  *VariableName\r
  )\r
{\r
  EFI_STATUS  Status;\r
  BOOLEAN     Valid;\r
  UINT32      Value;\r
\r
  GetFmpVariable (VariableName, &Valid, &Value);\r
  if (Valid) {\r
    Status = gRT->SetVariable (VariableName, &gEfiCallerIdGuid, 0, 0, NULL);\r
    if (EFI_ERROR (Status)) {\r
      DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Failed to delete variable %s.  Status = %r\n", mImageIdName, VariableName, Status));\r
    } else {\r
      DEBUG ((DEBUG_INFO, "FmpDxe(%s): Deleted variable %s\n", mImageIdName, VariableName));\r
    }\r
  }\r
}\r
\r
/**\r
  Retrieve the FMP Controller State UEFI Variable value.  Return NULL if\r
  the variable does not exist or if the size of the UEFI Variable is not the\r
  size of FMP_CONTROLLER_STATE.  The buffer for the UEFI Variable value\r
  if allocated using the UEFI Boot Service AllocatePool().\r
\r
  @param[in] Private  Private context structure for the managed controller.\r
\r
  @return  Pointer to the allocated FMP Controller State.  Returns NULL\r
           if the variable does not exist or is a different size than expected.\r
**/\r
static\r
FMP_CONTROLLER_STATE *\r
GetFmpControllerState (\r
  IN FIRMWARE_MANAGEMENT_PRIVATE_DATA  *Private\r
  )\r
{\r
  EFI_STATUS            Status;\r
  FMP_CONTROLLER_STATE  *FmpControllerState;\r
  UINTN                 Size;\r
\r
  FmpControllerState = NULL;\r
  Size               = 0;\r
  Status             = GetVariable2 (\r
                         Private->FmpStateVariableName,\r
                         &gEfiCallerIdGuid,\r
                         (VOID **)&FmpControllerState,\r
                         &Size\r
                         );\r
  if (EFI_ERROR (Status) || (FmpControllerState == NULL)) {\r
    DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Failed to get the controller state.  Status = %r\n", mImageIdName, Status));\r
  } else {\r
    if (Size == sizeof (*FmpControllerState)) {\r
      return FmpControllerState;\r
    }\r
\r
    DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Getting controller state returned a size different than expected. Size = 0x%x\n", mImageIdName, Size));\r
  }\r
\r
  if (FmpControllerState != NULL) {\r
    FreePool (FmpControllerState);\r
  }\r
\r
  return NULL;\r
}\r
\r
/**\r
  Generates a Null-terminated Unicode string UEFI Variable name from a base name\r
  and a hardware instance.  If the hardware instance value is 0, then the base\r
  name is returned.  If the hardware instance value is non-zero, then the 64-bit\r
  hardware instance value is converted to a 16 character hex string and appended\r
  to base name.  The UEFI Variable name returned is allocated using the UEFI\r
  Boot Service AllocatePool().\r
\r
  @param[in] HardwareInstance  64-bit hardware instance value.\r
  @param[in] BaseVariableName  Null-terminated Unicode string that is the base\r
                               name of the UEFI Variable.\r
\r
  @return  Pointer to the allocated UEFI Variable name.  Returns NULL if the\r
           UEFI Variable can not be allocated.\r
**/\r
static\r
CHAR16 *\r
GenerateFmpVariableName (\r
  IN  UINT64  HardwareInstance,\r
  IN  CHAR16  *BaseVariableName\r
  )\r
{\r
  UINTN   Size;\r
  CHAR16  *VariableName;\r
\r
  //\r
  // Allocate Unicode string with room for BaseVariableName and a 16 digit\r
  // hexadecimal value for the HardwareInstance value.\r
  //\r
  Size         = StrSize (BaseVariableName) + 16 * sizeof (CHAR16);\r
  VariableName = AllocateCopyPool (Size, BaseVariableName);\r
  if (VariableName == NULL) {\r
    DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Failed to generate variable name %s.\n", mImageIdName, BaseVariableName));\r
    return VariableName;\r
  }\r
\r
  if (HardwareInstance == 0) {\r
    return VariableName;\r
  }\r
\r
  UnicodeValueToStringS (\r
    &VariableName[StrLen (BaseVariableName)],\r
    Size,\r
    PREFIX_ZERO | RADIX_HEX,\r
    HardwareInstance,\r
    16\r
    );\r
  return VariableName;\r
}\r
\r
/**\r
  Generate the names of the UEFI Variables used to store state information for\r
  a managed controller.  The UEFI Variables names are a combination of a base\r
  name and an optional hardware instance value as a 16 character hex value.  If\r
  the hardware instance value is 0, then the 16 character hex value is not\r
  included.  These storage for the UEFI Variable names are allocated using the\r
  UEFI Boot Service AllocatePool() and the pointers are stored in the Private.\r
  The following are examples of variable names produces for hardware instance\r
  value 0 and value 0x1234567812345678.\r
\r
    FmpVersion\r
    FmpLsv\r
    LastAttemptStatus\r
    LastAttemptVersion\r
    FmpState\r
\r
    FmpVersion1234567812345678\r
    FmpLsv1234567812345678\r
    LastAttemptStatus1234567812345678\r
    LastAttemptVersion1234567812345678\r
    FmpState1234567812345678\r
\r
  @param[in,out] Private  Private context structure for the managed controller.\r
**/\r
VOID\r
GenerateFmpVariableNames (\r
  IN OUT FIRMWARE_MANAGEMENT_PRIVATE_DATA  *Private\r
  )\r
{\r
  EFI_STATUS            Status;\r
  VOID                  *Buffer;\r
  FMP_CONTROLLER_STATE  FmpControllerState;\r
\r
  if (Private->VersionVariableName != NULL) {\r
    FreePool (Private->VersionVariableName);\r
  }\r
\r
  if (Private->LsvVariableName != NULL) {\r
    FreePool (Private->LsvVariableName);\r
  }\r
\r
  if (Private->LastAttemptStatusVariableName != NULL) {\r
    FreePool (Private->LastAttemptStatusVariableName);\r
  }\r
\r
  if (Private->LastAttemptVersionVariableName != NULL) {\r
    FreePool (Private->LastAttemptVersionVariableName);\r
  }\r
\r
  if (Private->FmpStateVariableName != NULL) {\r
    FreePool (Private->FmpStateVariableName);\r
  }\r
\r
  Private->VersionVariableName = GenerateFmpVariableName (\r
                                   Private->Descriptor.HardwareInstance,\r
                                   VARNAME_VERSION\r
                                   );\r
  Private->LsvVariableName = GenerateFmpVariableName (\r
                               Private->Descriptor.HardwareInstance,\r
                               VARNAME_LSV\r
                               );\r
  Private->LastAttemptStatusVariableName = GenerateFmpVariableName (\r
                                             Private->Descriptor.HardwareInstance,\r
                                             VARNAME_LASTATTEMPTSTATUS\r
                                             );\r
  Private->LastAttemptVersionVariableName = GenerateFmpVariableName (\r
                                              Private->Descriptor.HardwareInstance,\r
                                              VARNAME_LASTATTEMPTVERSION\r
                                              );\r
  Private->FmpStateVariableName = GenerateFmpVariableName (\r
                                    Private->Descriptor.HardwareInstance,\r
                                    VARNAME_FMPSTATE\r
                                    );\r
\r
  DEBUG ((DEBUG_INFO, "FmpDxe(%s): Variable %g %s\n", mImageIdName, &gEfiCallerIdGuid, Private->VersionVariableName));\r
  DEBUG ((DEBUG_INFO, "FmpDxe(%s): Variable %g %s\n", mImageIdName, &gEfiCallerIdGuid, Private->LsvVariableName));\r
  DEBUG ((DEBUG_INFO, "FmpDxe(%s): Variable %g %s\n", mImageIdName, &gEfiCallerIdGuid, Private->LastAttemptStatusVariableName));\r
  DEBUG ((DEBUG_INFO, "FmpDxe(%s): Variable %g %s\n", mImageIdName, &gEfiCallerIdGuid, Private->LastAttemptVersionVariableName));\r
  DEBUG ((DEBUG_INFO, "FmpDxe(%s): Variable %g %s\n", mImageIdName, &gEfiCallerIdGuid, Private->FmpStateVariableName));\r
\r
  Buffer = GetFmpControllerState (Private);\r
  if (Buffer != NULL) {\r
    //\r
    // FMP Controller State was found with correct size.\r
    // Delete old variables if they exist.\r
    //\r
    FreePool (Buffer);\r
    DeleteFmpVariable (Private->VersionVariableName);\r
    DeleteFmpVariable (Private->LsvVariableName);\r
    DeleteFmpVariable (Private->LastAttemptStatusVariableName);\r
    DeleteFmpVariable (Private->LastAttemptVersionVariableName);\r
    return;\r
  }\r
\r
  //\r
  // FMP Controller State was either not found or is wrong size.\r
  // Create a new FMP Controller State variable with the correct size.\r
  //\r
  DEBUG ((DEBUG_INFO, "FmpDxe(%s): Create controller state\n", mImageIdName));\r
  GetFmpVariable (\r
    Private->VersionVariableName,\r
    &FmpControllerState.VersionValid,\r
    &FmpControllerState.Version\r
    );\r
  GetFmpVariable (\r
    Private->LsvVariableName,\r
    &FmpControllerState.LsvValid,\r
    &FmpControllerState.Lsv\r
    );\r
  GetFmpVariable (\r
    Private->LastAttemptStatusVariableName,\r
    &FmpControllerState.LastAttemptStatusValid,\r
    &FmpControllerState.LastAttemptStatus\r
    );\r
  GetFmpVariable (\r
    Private->LastAttemptVersionVariableName,\r
    &FmpControllerState.LastAttemptVersionValid,\r
    &FmpControllerState.LastAttemptVersion\r
    );\r
  Status = gRT->SetVariable (\r
                  Private->FmpStateVariableName,\r
                  &gEfiCallerIdGuid,\r
                  EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS,\r
                  sizeof (FmpControllerState),\r
                  &FmpControllerState\r
                  );\r
  if (EFI_ERROR (Status)) {\r
    //\r
    // Failed to create FMP Controller State.  In this case, do not\r
    // delete the individual variables.  They can be used again on next boot\r
    // to create the FMP Controller State.\r
    //\r
    DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Failed to create controller state.  Status = %r\n", mImageIdName, Status));\r
  } else {\r
    DeleteFmpVariable (Private->VersionVariableName);\r
    DeleteFmpVariable (Private->LsvVariableName);\r
    DeleteFmpVariable (Private->LastAttemptStatusVariableName);\r
    DeleteFmpVariable (Private->LastAttemptVersionVariableName);\r
  }\r
}\r
\r
/**\r
  Returns the value used to fill in the Version field of the\r
  EFI_FIRMWARE_IMAGE_DESCRIPTOR structure that is returned by the GetImageInfo()\r
  service of the Firmware Management Protocol.  The value is read from a UEFI\r
  variable.  If the UEFI variables does not exist, then a default version value\r
  is returned.\r
\r
  UEFI Variable accessed: GUID = gEfiCallerIdGuid, Name = L"FmpState"\r
\r
  @param[in] Private  Private context structure for the managed controller.\r
\r
  @return  The version of the firmware image in the firmware device.\r
**/\r
UINT32\r
GetVersionFromVariable (\r
  IN FIRMWARE_MANAGEMENT_PRIVATE_DATA  *Private\r
  )\r
{\r
  FMP_CONTROLLER_STATE  *FmpControllerState;\r
  UINT32                Value;\r
\r
  Value              = DEFAULT_VERSION;\r
  FmpControllerState = GetFmpControllerState (Private);\r
  if (FmpControllerState != NULL) {\r
    if (FmpControllerState->VersionValid) {\r
      Value = FmpControllerState->Version;\r
      DEBUG ((\r
        DEBUG_INFO,\r
        "FmpDxe(%s): Get variable %g %s Version %08x\n",\r
        mImageIdName,\r
        &gEfiCallerIdGuid,\r
        Private->FmpStateVariableName,\r
        Value\r
        ));\r
    }\r
\r
    FreePool (FmpControllerState);\r
  }\r
\r
  return Value;\r
}\r
\r
/**\r
  Returns the value used to fill in the LowestSupportedVersion field of the\r
  EFI_FIRMWARE_IMAGE_DESCRIPTOR structure that is returned by the GetImageInfo()\r
  service of the Firmware Management Protocol.  The value is read from a UEFI\r
  variable.  If the UEFI variables does not exist, then a default lowest\r
  supported version value is returned.\r
\r
  UEFI Variable accessed: GUID = gEfiCallerIdGuid, Name = L"FmpState"\r
\r
  @param[in] Private  Private context structure for the managed controller.\r
\r
  @return  The lowest supported version of the firmware image in the firmware\r
           device.\r
**/\r
UINT32\r
GetLowestSupportedVersionFromVariable (\r
  IN FIRMWARE_MANAGEMENT_PRIVATE_DATA  *Private\r
  )\r
{\r
  FMP_CONTROLLER_STATE  *FmpControllerState;\r
  UINT32                Value;\r
\r
  Value              = DEFAULT_LOWESTSUPPORTEDVERSION;\r
  FmpControllerState = GetFmpControllerState (Private);\r
  if (FmpControllerState != NULL) {\r
    if (FmpControllerState->LsvValid) {\r
      Value = FmpControllerState->Lsv;\r
      DEBUG ((\r
        DEBUG_INFO,\r
        "FmpDxe(%s): Get variable %g %s LowestSupportedVersion %08x\n",\r
        mImageIdName,\r
        &gEfiCallerIdGuid,\r
        Private->FmpStateVariableName,\r
        Value\r
        ));\r
    }\r
\r
    FreePool (FmpControllerState);\r
  }\r
\r
  return Value;\r
}\r
\r
/**\r
  Returns the value used to fill in the LastAttemptStatus field of the\r
  EFI_FIRMWARE_IMAGE_DESCRIPTOR structure that is returned by the GetImageInfo()\r
  service of the Firmware Management Protocol.  The value is read from a UEFI\r
  variable.  If the UEFI variables does not exist, then a default last attempt\r
  status value is returned.\r
\r
  UEFI Variable accessed: GUID = gEfiCallerIdGuid, Name = L"FmpState"\r
\r
  @param[in] Private  Private context structure for the managed controller.\r
\r
  @return  The last attempt status value for the most recent capsule update.\r
**/\r
UINT32\r
GetLastAttemptStatusFromVariable (\r
  IN FIRMWARE_MANAGEMENT_PRIVATE_DATA  *Private\r
  )\r
{\r
  FMP_CONTROLLER_STATE  *FmpControllerState;\r
  UINT32                Value;\r
\r
  Value              = DEFAULT_LASTATTEMPTSTATUS;\r
  FmpControllerState = GetFmpControllerState (Private);\r
  if (FmpControllerState != NULL) {\r
    if (FmpControllerState->LastAttemptStatusValid) {\r
      Value = FmpControllerState->LastAttemptStatus;\r
      DEBUG ((\r
        DEBUG_INFO,\r
        "FmpDxe(%s): Get variable %g %s LastAttemptStatus %08x\n",\r
        mImageIdName,\r
        &gEfiCallerIdGuid,\r
        Private->FmpStateVariableName,\r
        Value\r
        ));\r
    }\r
\r
    FreePool (FmpControllerState);\r
  }\r
\r
  return Value;\r
}\r
\r
/**\r
  Returns the value used to fill in the LastAttemptVersion field of the\r
  EFI_FIRMWARE_IMAGE_DESCRIPTOR structure that is returned by the GetImageInfo()\r
  service of the Firmware Management Protocol.  The value is read from a UEFI\r
  variable.  If the UEFI variables does not exist, then a default last attempt\r
  version value is returned.\r
\r
  UEFI Variable accessed: GUID = gEfiCallerIdGuid, Name = L"FmpState"\r
\r
  @param[in] Private  Private context structure for the managed controller.\r
\r
  @return  The last attempt version value for the most recent capsule update.\r
**/\r
UINT32\r
GetLastAttemptVersionFromVariable (\r
  IN FIRMWARE_MANAGEMENT_PRIVATE_DATA  *Private\r
  )\r
{\r
  FMP_CONTROLLER_STATE  *FmpControllerState;\r
  UINT32                Value;\r
\r
  Value              = DEFAULT_LASTATTEMPTVERSION;\r
  FmpControllerState = GetFmpControllerState (Private);\r
  if (FmpControllerState != NULL) {\r
    if (FmpControllerState->LastAttemptVersionValid) {\r
      Value = FmpControllerState->LastAttemptVersion;\r
      DEBUG ((\r
        DEBUG_INFO,\r
        "FmpDxe(%s): Get variable %g %s LastAttemptVersion %08x\n",\r
        mImageIdName,\r
        &gEfiCallerIdGuid,\r
        Private->FmpStateVariableName,\r
        Value\r
        ));\r
    }\r
\r
    FreePool (FmpControllerState);\r
  }\r
\r
  return Value;\r
}\r
\r
/**\r
  Saves the version current of the firmware image in the firmware device to a\r
  UEFI variable.\r
\r
  UEFI Variable accessed: GUID = gEfiCallerIdGuid, Name = L"FmpState"\r
\r
  @param[in] Private  Private context structure for the managed controller.\r
  @param[in] Version  The version of the firmware image in the firmware device.\r
**/\r
VOID\r
SetVersionInVariable (\r
  IN FIRMWARE_MANAGEMENT_PRIVATE_DATA  *Private,\r
  IN UINT32                            Version\r
  )\r
{\r
  EFI_STATUS            Status;\r
  FMP_CONTROLLER_STATE  *FmpControllerState;\r
  BOOLEAN               Update;\r
\r
  FmpControllerState = GetFmpControllerState (Private);\r
  if (FmpControllerState == NULL) {\r
    //\r
    // Can not update value if FMP Controller State does not exist.\r
    // This variable is guaranteed to be created by GenerateFmpVariableNames().\r
    //\r
    return;\r
  }\r
\r
  Update = FALSE;\r
  if (!FmpControllerState->VersionValid) {\r
    Update = TRUE;\r
  }\r
\r
  if (FmpControllerState->Version != Version) {\r
    Update = TRUE;\r
  }\r
\r
  if (!Update) {\r
    DEBUG ((DEBUG_INFO, "FmpDxe(%s): No need to update controller state.  Same value as before.\n", mImageIdName));\r
  } else {\r
    FmpControllerState->VersionValid = TRUE;\r
    FmpControllerState->Version      = Version;\r
    Status                           = gRT->SetVariable (\r
                                              Private->FmpStateVariableName,\r
                                              &gEfiCallerIdGuid,\r
                                              EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS,\r
                                              sizeof (*FmpControllerState),\r
                                              FmpControllerState\r
                                              );\r
    if (EFI_ERROR (Status)) {\r
      DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Failed to update controller state.  Status = %r\n", mImageIdName, Status));\r
    } else {\r
      DEBUG ((\r
        DEBUG_INFO,\r
        "FmpDxe(%s): Set variable %g %s Version %08x\n",\r
        mImageIdName,\r
        &gEfiCallerIdGuid,\r
        Private->FmpStateVariableName,\r
        Version\r
        ));\r
    }\r
  }\r
\r
  FreePool (FmpControllerState);\r
}\r
\r
/**\r
  Saves the lowest supported version current of the firmware image in the\r
  firmware device to a UEFI variable.\r
\r
  UEFI Variable accessed: GUID = gEfiCallerIdGuid, Name = L"FmpState"\r
\r
  @param[in] Private                 Private context structure for the managed\r
                                     controller.\r
  @param[in] LowestSupportedVersion  The lowest supported version of the\r
                                     firmware image in the firmware device.\r
**/\r
VOID\r
SetLowestSupportedVersionInVariable (\r
  IN FIRMWARE_MANAGEMENT_PRIVATE_DATA  *Private,\r
  IN UINT32                            LowestSupportedVersion\r
  )\r
{\r
  EFI_STATUS            Status;\r
  FMP_CONTROLLER_STATE  *FmpControllerState;\r
  BOOLEAN               Update;\r
\r
  FmpControllerState = GetFmpControllerState (Private);\r
  if (FmpControllerState == NULL) {\r
    //\r
    // Can not update value if FMP Controller State does not exist.\r
    // This variable is guaranteed to be created by GenerateFmpVariableNames().\r
    //\r
    return;\r
  }\r
\r
  Update = FALSE;\r
  if (!FmpControllerState->LsvValid) {\r
    Update = TRUE;\r
  }\r
\r
  if (FmpControllerState->Lsv < LowestSupportedVersion) {\r
    Update = TRUE;\r
  }\r
\r
  if (!Update) {\r
    DEBUG ((DEBUG_INFO, "FmpDxe(%s): No need to update controller state.  Same value as before.\n", mImageIdName));\r
  } else {\r
    FmpControllerState->LsvValid = TRUE;\r
    FmpControllerState->Lsv      = LowestSupportedVersion;\r
    Status                       = gRT->SetVariable (\r
                                          Private->FmpStateVariableName,\r
                                          &gEfiCallerIdGuid,\r
                                          EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS,\r
                                          sizeof (*FmpControllerState),\r
                                          FmpControllerState\r
                                          );\r
    if (EFI_ERROR (Status)) {\r
      DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Failed to update controller state.  Status = %r\n", mImageIdName, Status));\r
    } else {\r
      DEBUG ((\r
        DEBUG_INFO,\r
        "FmpDxe(%s): Set variable %g %s LowestSupportedVersion %08x\n",\r
        mImageIdName,\r
        &gEfiCallerIdGuid,\r
        Private->FmpStateVariableName,\r
        LowestSupportedVersion\r
        ));\r
    }\r
  }\r
\r
  FreePool (FmpControllerState);\r
}\r
\r
/**\r
  Saves the last attempt status value of the most recent FMP capsule update to a\r
  UEFI variable.\r
\r
  UEFI Variable accessed: GUID = gEfiCallerIdGuid, Name = L"FmpState"\r
\r
  @param[in] Private            Private context structure for the managed\r
                                controller.\r
  @param[in] LastAttemptStatus  The last attempt status of the most recent FMP\r
                                capsule update.\r
**/\r
VOID\r
SetLastAttemptStatusInVariable (\r
  IN FIRMWARE_MANAGEMENT_PRIVATE_DATA  *Private,\r
  IN UINT32                            LastAttemptStatus\r
  )\r
{\r
  EFI_STATUS            Status;\r
  FMP_CONTROLLER_STATE  *FmpControllerState;\r
  BOOLEAN               Update;\r
\r
  FmpControllerState = GetFmpControllerState (Private);\r
  if (FmpControllerState == NULL) {\r
    //\r
    // Can not update value if FMP Controller State does not exist.\r
    // This variable is guaranteed to be created by GenerateFmpVariableNames().\r
    //\r
    return;\r
  }\r
\r
  Update = FALSE;\r
  if (!FmpControllerState->LastAttemptStatusValid) {\r
    Update = TRUE;\r
  }\r
\r
  if (FmpControllerState->LastAttemptStatus != LastAttemptStatus) {\r
    Update = TRUE;\r
  }\r
\r
  if (!Update) {\r
    DEBUG ((DEBUG_INFO, "FmpDxe(%s): No need to update controller state.  Same value as before.\n", mImageIdName));\r
  } else {\r
    FmpControllerState->LastAttemptStatusValid = TRUE;\r
    FmpControllerState->LastAttemptStatus      = LastAttemptStatus;\r
    Status                                     = gRT->SetVariable (\r
                                                        Private->FmpStateVariableName,\r
                                                        &gEfiCallerIdGuid,\r
                                                        EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS,\r
                                                        sizeof (*FmpControllerState),\r
                                                        FmpControllerState\r
                                                        );\r
    if (EFI_ERROR (Status)) {\r
      DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Failed to update controller state.  Status = %r\n", mImageIdName, Status));\r
    } else {\r
      DEBUG ((\r
        DEBUG_INFO,\r
        "FmpDxe(%s): Set variable %g %s LastAttemptStatus %08x\n",\r
        mImageIdName,\r
        &gEfiCallerIdGuid,\r
        Private->FmpStateVariableName,\r
        LastAttemptStatus\r
        ));\r
    }\r
  }\r
\r
  FreePool (FmpControllerState);\r
}\r
\r
/**\r
  Saves the last attempt version value of the most recent FMP capsule update to\r
  a UEFI variable.\r
\r
  UEFI Variable accessed: GUID = gEfiCallerIdGuid, Name = L"FmpState"\r
\r
  @param[in] Private             Private context structure for the managed\r
                                 controller.\r
  @param[in] LastAttemptVersion  The last attempt version value of the most\r
                                 recent FMP capsule update.\r
**/\r
VOID\r
SetLastAttemptVersionInVariable (\r
  IN FIRMWARE_MANAGEMENT_PRIVATE_DATA  *Private,\r
  IN UINT32                            LastAttemptVersion\r
  )\r
{\r
  EFI_STATUS            Status;\r
  FMP_CONTROLLER_STATE  *FmpControllerState;\r
  BOOLEAN               Update;\r
\r
  FmpControllerState = GetFmpControllerState (Private);\r
  if (FmpControllerState == NULL) {\r
    //\r
    // Can not update value if FMP Controller State does not exist.\r
    // This variable is guaranteed to be created by GenerateFmpVariableNames().\r
    //\r
    return;\r
  }\r
\r
  Update = FALSE;\r
  if (!FmpControllerState->LastAttemptVersionValid) {\r
    Update = TRUE;\r
  }\r
\r
  if (FmpControllerState->LastAttemptVersion != LastAttemptVersion) {\r
    Update = TRUE;\r
  }\r
\r
  if (!Update) {\r
    DEBUG ((DEBUG_INFO, "FmpDxe(%s): No need to update controller state.  Same value as before.\n", mImageIdName));\r
  } else {\r
    FmpControllerState->LastAttemptVersionValid = TRUE;\r
    FmpControllerState->LastAttemptVersion      = LastAttemptVersion;\r
    Status                                      = gRT->SetVariable (\r
                                                         Private->FmpStateVariableName,\r
                                                         &gEfiCallerIdGuid,\r
                                                         EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS,\r
                                                         sizeof (*FmpControllerState),\r
                                                         FmpControllerState\r
                                                         );\r
    if (EFI_ERROR (Status)) {\r
      DEBUG ((DEBUG_ERROR, "FmpDxe(%s): Failed to update controller state.  Status = %r\n", mImageIdName, Status));\r
    } else {\r
      DEBUG ((\r
        DEBUG_INFO,\r
        "FmpDxe(%s): Set variable %g %s LastAttemptVersion %08x\n",\r
        mImageIdName,\r
        &gEfiCallerIdGuid,\r
        Private->FmpStateVariableName,\r
        LastAttemptVersion\r
        ));\r
    }\r
  }\r
\r
  FreePool (FmpControllerState);\r
}\r
\r
/**\r
  Attempts to lock a single UEFI Variable propagating the error state of the\r
  first lock attempt that fails.  Uses gEfiCallerIdGuid as the variable GUID.\r
\r
  @param[in] PreviousStatus  The previous UEFI Variable lock attempt status.\r
  @param[in] VariableLock    The EDK II Variable Lock Protocol instance.\r
  @param[in] VariableName    The name of the UEFI Variable to lock.\r
\r
  @retval  EFI_SUCCESS  The UEFI Variable was locked and the previous variable\r
                        lock attempt also succeeded.\r
  @retval  Other        The UEFI Variable could not be locked or the previous\r
                        variable lock attempt failed.\r
**/\r
static\r
EFI_STATUS\r
LockFmpVariable (\r
  IN EFI_STATUS                      PreviousStatus,\r
  IN EDKII_VARIABLE_POLICY_PROTOCOL  *VariablePolicy,\r
  IN CHAR16                          *VariableName\r
  )\r
{\r
  EFI_STATUS  Status;\r
\r
  // If success, go ahead and set the policies to protect the target variables.\r
  Status = RegisterBasicVariablePolicy (\r
             VariablePolicy,\r
             &gEfiCallerIdGuid,\r
             VariableName,\r
             VARIABLE_POLICY_NO_MIN_SIZE,\r
             VARIABLE_POLICY_NO_MAX_SIZE,\r
             VARIABLE_POLICY_NO_MUST_ATTR,\r
             VARIABLE_POLICY_NO_CANT_ATTR,\r
             VARIABLE_POLICY_TYPE_LOCK_NOW\r
             );\r
  if (EFI_ERROR (Status)) {\r
    DEBUG ((\r
      DEBUG_ERROR,\r
      "FmpDxe(%s): Failed to lock variable %g %s. Status = %r\n",\r
      mImageIdName,\r
      &gEfiCallerIdGuid,\r
      VariableName,\r
      Status\r
      ));\r
  }\r
\r
  if (EFI_ERROR (PreviousStatus)) {\r
    return PreviousStatus;\r
  }\r
\r
  return Status;\r
}\r
\r
/**\r
  Locks all the UEFI Variables that use gEfiCallerIdGuid of the currently\r
  executing module.\r
\r
  @param[in] Private  Private context structure for the managed controller.\r
\r
  @retval  EFI_SUCCESS      All UEFI variables are locked.\r
  @retval  EFI_UNSUPPORTED  Variable Lock Protocol not found.\r
  @retval  Other            One of the UEFI variables could not be locked.\r
**/\r
EFI_STATUS\r
LockAllFmpVariables (\r
  FIRMWARE_MANAGEMENT_PRIVATE_DATA  *Private\r
  )\r
{\r
  EFI_STATUS                      Status;\r
  EDKII_VARIABLE_POLICY_PROTOCOL  *VariablePolicy;\r
\r
  // Locate the VariablePolicy protocol.\r
  Status = gBS->LocateProtocol (&gEdkiiVariablePolicyProtocolGuid, NULL, (VOID **)&VariablePolicy);\r
  if (EFI_ERROR (Status)) {\r
    DEBUG ((DEBUG_ERROR, "FmpDxe %a - Could not locate VariablePolicy protocol! %r\n", __FUNCTION__, Status));\r
    return Status;\r
  }\r
\r
  Status = EFI_SUCCESS;\r
  Status = LockFmpVariable (Status, VariablePolicy, Private->VersionVariableName);\r
  Status = LockFmpVariable (Status, VariablePolicy, Private->LsvVariableName);\r
  Status = LockFmpVariable (Status, VariablePolicy, Private->LastAttemptStatusVariableName);\r
  Status = LockFmpVariable (Status, VariablePolicy, Private->LastAttemptVersionVariableName);\r
  Status = LockFmpVariable (Status, VariablePolicy, Private->FmpStateVariableName);\r
\r
  return Status;\r
}\r