audk/SecurityPkg/Tcg/MemoryOverwriteRequestControlLock/TcgMorLockSmm.c

/** @file
   TCG MOR (Memory Overwrite Request) Lock Control Driver SMM wrapper.
   
Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials 
are licensed and made available under the terms and conditions of the BSD License 
which accompanies this distribution.  The full text of the license may be found at 
http://opensource.org/licenses/bsd-license.php

THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#include <PiSmm.h>
#include <Library/SmmServicesTableLib.h>
#include <Library/DebugLib.h>
#include <Protocol/SmmVarCheck.h>
#include <Protocol/SmmVariable.h>
#include "TcgMorLock.h"

EFI_SMM_VARIABLE_PROTOCOL *mSmmVariable;

/**
  This service is a wrapper for the UEFI Runtime Service GetVariable().

  @param  VariableName the name of the vendor's variable, it's a Null-Terminated Unicode String
  @param  VendorGuid   Unify identifier for vendor.
  @param  Attributes   Point to memory location to return the attributes of variable. If the point
                       is NULL, the parameter would be ignored.
  @param  DataSize     As input, point to the maximum size of return Data-Buffer.
                       As output, point to the actual size of the returned Data-Buffer.
  @param  Data         Point to return Data-Buffer.

  @retval  EFI_SUCCESS            The function completed successfully.
  @retval  EFI_NOT_FOUND          The variable was not found.
  @retval  EFI_BUFFER_TOO_SMALL   The DataSize is too small for the result. DataSize has
                                  been updated with the size needed to complete the request.
  @retval  EFI_INVALID_PARAMETER  VariableName is NULL.
  @retval  EFI_INVALID_PARAMETER  VendorGuid is NULL.
  @retval  EFI_INVALID_PARAMETER  DataSize is NULL.
  @retval  EFI_INVALID_PARAMETER  The DataSize is not too small and Data is NULL.
  @retval  EFI_DEVICE_ERROR       The variable could not be retrieved due to a hardware error.
  @retval  EFI_SECURITY_VIOLATION The variable could not be retrieved due to an authentication failure.
**/
EFI_STATUS
EFIAPI
InternalGetVariable (
  IN      CHAR16                   *VariableName,
  IN      EFI_GUID                 *VendorGuid,
  OUT     UINT32                   *Attributes OPTIONAL,
  IN OUT  UINTN                    *DataSize,
  OUT     VOID                     *Data
  )
{
  return mSmmVariable->SmmGetVariable (
                         VariableName,
                         VendorGuid,
                         Attributes,
                         DataSize,
                         Data
                         );
}

/**
  This service is a wrapper for the UEFI Runtime Service SetVariable()

  @param  VariableName the name of the vendor's variable, as a
                       Null-Terminated Unicode String
  @param  VendorGuid   Unify identifier for vendor.
  @param  Attributes   Point to memory location to return the attributes of variable. If the point
                       is NULL, the parameter would be ignored.
  @param  DataSize     The size in bytes of Data-Buffer.
  @param  Data         Point to the content of the variable.

  @retval  EFI_SUCCESS            The firmware has successfully stored the variable and its data as
                                  defined by the Attributes.
  @retval  EFI_INVALID_PARAMETER  An invalid combination of attribute bits was supplied, or the
                                  DataSize exceeds the maximum allowed.
  @retval  EFI_INVALID_PARAMETER  VariableName is an empty Unicode string.
  @retval  EFI_OUT_OF_RESOURCES   Not enough storage is available to hold the variable and its data.
  @retval  EFI_DEVICE_ERROR       The variable could not be saved due to a hardware failure.
  @retval  EFI_WRITE_PROTECTED    The variable in question is read-only.
  @retval  EFI_WRITE_PROTECTED    The variable in question cannot be deleted.
  @retval  EFI_SECURITY_VIOLATION The variable could not be written due to EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS
                                  set but the AuthInfo does NOT pass the validation check carried
                                  out by the firmware.
  @retval  EFI_NOT_FOUND          The variable trying to be updated or deleted was not found.

**/
EFI_STATUS
EFIAPI
InternalSetVariable (
  IN CHAR16                       *VariableName,
  IN EFI_GUID                     *VendorGuid,
  IN UINT32                       Attributes,
  IN UINTN                        DataSize,
  IN VOID                         *Data
  )
{
  return mSmmVariable->SmmSetVariable (
                         VariableName,
                         VendorGuid,
                         Attributes,
                         DataSize,
                         Data
                         );
}

/**
  Entry Point for MOR Lock Control driver.

  @param[in] ImageHandle    The firmware allocated handle for the EFI image.
  @param[in] SystemTable    A pointer to the EFI System Table.

  @retval EFI_SUCCESS       EntryPoint runs successfully.

**/
EFI_STATUS
EFIAPI
MorLockDriverEntryPointSmm (
  IN EFI_HANDLE         ImageHandle,
  IN EFI_SYSTEM_TABLE   *SystemTable
  )
{
  EFI_STATUS                    Status;
  EDKII_SMM_VAR_CHECK_PROTOCOL  *SmmVarCheck;

  //
  // This driver link to Smm Variable driver
  //
  DEBUG ((EFI_D_INFO, "MorLockDriverEntryPointSmm\n"));
  
  Status = gSmst->SmmLocateProtocol (
                  &gEfiSmmVariableProtocolGuid,
                  NULL,
                  (VOID **) &mSmmVariable
                  );
  ASSERT_EFI_ERROR (Status);

  Status = gSmst->SmmLocateProtocol (
                  &gEdkiiSmmVarCheckProtocolGuid,
                  NULL,
                  (VOID **) &SmmVarCheck
                  );
  ASSERT_EFI_ERROR (Status);

  Status = MorLockDriverInit ();
  if (EFI_ERROR (Status)) {
    return Status;
  }

  Status = SmmVarCheck->SmmRegisterSetVariableCheckHandler (SetVariableCheckHandlerMor);
  ASSERT_EFI_ERROR (Status);

  return Status;
}