Пример #1
0
/**
  Check the integrity of firmware volume header.

  @param[in] FwVolHeader - A pointer to a firmware volume header

  @retval  EFI_SUCCESS   - The firmware volume is consistent
  @retval  EFI_NOT_FOUND - The firmware volume has been corrupted.

**/
EFI_STATUS
ValidateFvHeader (
  IN EFI_FIRMWARE_VOLUME_HEADER   *FwVolHeader
  )
{
  UINT16  Checksum;

  //
  // Verify the header revision, header signature, length
  // Length of FvBlock cannot be 2**64-1
  // HeaderLength cannot be an odd number
  //
  if ((FwVolHeader->Revision != EFI_FVH_REVISION) ||
      (FwVolHeader->Signature != EFI_FVH_SIGNATURE) ||
      (FwVolHeader->FvLength != EMU_FVB_SIZE) ||
      (FwVolHeader->HeaderLength != EMU_FV_HEADER_LENGTH)
      ) {
    DEBUG ((EFI_D_INFO, "EMU Variable FVB: Basic FV headers were invalid\n"));
    return EFI_NOT_FOUND;
  }
  //
  // Verify the header checksum
  //
  Checksum = CalculateSum16((VOID*) FwVolHeader, FwVolHeader->HeaderLength);

  if (Checksum != 0) {
    DEBUG ((EFI_D_INFO, "EMU Variable FVB: FV checksum was invalid\n"));
    return EFI_NOT_FOUND;
  }

  return EFI_SUCCESS;
}
Пример #2
0
/**
  Check the integrity of firmware volume header.

  @param[in] FwVolHeader - A pointer to a firmware volume header

  @retval  EFI_SUCCESS   - The firmware volume is consistent
  @retval  EFI_NOT_FOUND - The firmware volume has been corrupted.

**/
EFI_STATUS
ValidateFvHeader (
  IN  NOR_FLASH_INSTANCE *Instance
  )
{
  UINT16                      Checksum;
  EFI_FIRMWARE_VOLUME_HEADER  *FwVolHeader;
  VARIABLE_STORE_HEADER       *VariableStoreHeader;
  UINTN                       VariableStoreLength;
  UINTN						  FvLength;

  FwVolHeader = (EFI_FIRMWARE_VOLUME_HEADER*)Instance->RegionBaseAddress;

  FvLength = PcdGet32(PcdFlashNvStorageVariableSize) + PcdGet32(PcdFlashNvStorageFtwWorkingSize) +
      PcdGet32(PcdFlashNvStorageFtwSpareSize);

  //
  // Verify the header revision, header signature, length
  // Length of FvBlock cannot be 2**64-1
  // HeaderLength cannot be an odd number
  //
  if (   (FwVolHeader->Revision  != EFI_FVH_REVISION)
      || (FwVolHeader->Signature != EFI_FVH_SIGNATURE)
      || (FwVolHeader->FvLength  != FvLength)
      )
  {
    DEBUG ((EFI_D_ERROR, "ValidateFvHeader: No Firmware Volume header present\n"));
    return EFI_NOT_FOUND;
  }

  // Check the Firmware Volume Guid
  if( CompareGuid (&FwVolHeader->FileSystemGuid, &gEfiSystemNvDataFvGuid) == FALSE ) {
    DEBUG ((EFI_D_ERROR, "ValidateFvHeader: Firmware Volume Guid non-compatible\n"));
    return EFI_NOT_FOUND;
  }

  // Verify the header checksum
  Checksum = CalculateSum16((UINT16*)FwVolHeader, FwVolHeader->HeaderLength);
  if (Checksum != 0) {
    DEBUG ((EFI_D_ERROR, "ValidateFvHeader: FV checksum is invalid (Checksum:0x%X)\n",Checksum));
    return EFI_NOT_FOUND;
  }

  VariableStoreHeader = (VARIABLE_STORE_HEADER*)((UINTN)FwVolHeader + FwVolHeader->HeaderLength);

  // Check the Variable Store Guid
  if( CompareGuid (&VariableStoreHeader->Signature, &gEfiVariableGuid) == FALSE ) {
    DEBUG ((EFI_D_ERROR, "ValidateFvHeader: Variable Store Guid non-compatible\n"));
    return EFI_NOT_FOUND;
  }

  VariableStoreLength = PcdGet32 (PcdFlashNvStorageVariableSize) - FwVolHeader->HeaderLength;
  if (VariableStoreHeader->Size != VariableStoreLength) {
    DEBUG ((EFI_D_ERROR, "ValidateFvHeader: Variable Store Length does not match\n"));
    return EFI_NOT_FOUND;
  }

  return EFI_SUCCESS;
}
Пример #3
0
/**
  Verify checksum of the firmware volume header.

  @param  FvHeader       Points to the firmware volume header to be checked

  @retval TRUE           Checksum verification passed
  @retval FALSE          Checksum verification failed

**/
BOOLEAN
VerifyFvHeaderChecksum (
  IN EFI_FIRMWARE_VOLUME_HEADER *FvHeader
  )
{
  UINT16  Checksum;

  Checksum = CalculateSum16 ((UINT16 *) FvHeader, FvHeader->HeaderLength);

  if (Checksum == 0) {
    return TRUE;
  } else {
    return FALSE;
  }
}
Пример #4
0
//
// will not parse compressed sections
//
EFI_STATUS
VerifyFv (
  IN EFI_FIRMWARE_VOLUME_HEADER   *FvHeader
  )
/*++

Routine Description:

  Verify the current pointer points to a valid FV header.

Arguments:

  FvHeader     Pointer to an alleged FV file.

Returns:

  EFI_SUCCESS             The FV header is valid.
  EFI_VOLUME_CORRUPTED    The FV header is not valid.
  EFI_INVALID_PARAMETER   A required parameter was NULL.
  EFI_ABORTED             Operation aborted.

--*/
{
  UINT16  Checksum;

  //
  // Verify input parameters
  //
  if (FvHeader == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  if (FvHeader->Signature != EFI_FVH_SIGNATURE) {
    Error (NULL, 0, 0006, "invalid FV header signature", NULL);
    return EFI_VOLUME_CORRUPTED;
  }
  //
  // Verify header checksum
  //
  Checksum = CalculateSum16 ((UINT16 *) FvHeader, FvHeader->HeaderLength / sizeof (UINT16));

  if (Checksum != 0) {
    Error (NULL, 0, 0006, "invalid FV header checksum", NULL);
    return EFI_ABORTED;
  }

  return EFI_SUCCESS;
}
Пример #5
0
/**
  Returns the two's complement checksum of all elements in a buffer of
  16-bit values.

  This function first calculates the sum of the 16-bit values in the buffer
  specified by Buffer and Length.  The carry bits in the result of addition
  are dropped. Then, the two's complement of the sum is returned.  If Length
  is 0, then 0 is returned.

  If Buffer is NULL, then ASSERT().
  If Buffer is not aligned on a 16-bit boundary, then ASSERT().
  If Length is not aligned on a 16-bit boundary, then ASSERT().
  If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().

  @param  Buffer      Pointer to the buffer to carry out the checksum operation.
  @param  Length      The size, in bytes, of Buffer.

  @return Checksum    The 2's complement checksum of Buffer.

**/
UINT16
EFIAPI
CalculateCheckSum16 (
  IN      CONST UINT16             *Buffer,
  IN      UINTN                     Length
  )
{
  UINT16     CheckSum;

  CheckSum = CalculateSum16 (Buffer, Length);

  //
  // Return the checksum based on 2's complement.
  //
  return (UINT16) (0x10000 - CheckSum);
}
Пример #6
0
UINT16
CalculateChecksum16 (
  IN UINT16       *Buffer,
  IN UINTN        Size
  )
/*++
  
Routine Description::

  This function calculates the value needed for a valid UINT16 checksum

Arguments:

  Buffer      Pointer to buffer containing byte data of component.
  Size        Size of the buffer

Returns:

  The 16 bit checksum value needed.

--*/
{
  return (UINT16) (0x10000 - CalculateSum16 (Buffer, Size));
}