C++ (Cpp) calc_esv_lengthの例

コード例 #1

ファイル: AS_DCP_PCM.cpp プロジェクト: lucat/opendcp-1

static ui32_t
calc_CBR_frame_size(ASDCP::WriterInfo& Info, const ASDCP::PCM::AudioDescriptor& ADesc)
{
  ui32_t CBR_frame_size = 0;

  if ( Info.EncryptedEssence )
    {
      CBR_frame_size =
	SMPTE_UL_LENGTH
	+ MXF_BER_LENGTH
	+ klv_cryptinfo_size
	+ calc_esv_length(ASDCP::PCM::CalcFrameBufferSize(ADesc), 0)
	+ ( Info.UsesHMAC ? klv_intpack_size : (MXF_BER_LENGTH * 3) );
    }
  else
    {
      CBR_frame_size = ASDCP::PCM::CalcFrameBufferSize(ADesc) + SMPTE_UL_LENGTH + MXF_BER_LENGTH;
    }

  return CBR_frame_size;
}

コード例 #2

ファイル: AS_DCP_MXF.cpp プロジェクト: ArthurGeorget/asdcplib

Result_t
ASDCP::EncryptFrameBuffer(const ASDCP::FrameBuffer& FBin, ASDCP::FrameBuffer& FBout, AESEncContext* Ctx)
{
  ASDCP_TEST_NULL(Ctx);
  FBout.Size(0);

  // size the buffer
  Result_t result = FBout.Capacity(calc_esv_length(FBin.Size(), FBin.PlaintextOffset()));

  // write the IV
  byte_t* p = FBout.Data();

  // write the IV to the frame buffer
  Ctx->GetIVec(p);
  p += CBC_BLOCK_SIZE;


  // encrypt the check value to the frame buffer
  if ( ASDCP_SUCCESS(result) )
    {
      result = Ctx->EncryptBlock(ESV_CheckValue, p, CBC_BLOCK_SIZE);
      p += CBC_BLOCK_SIZE;
    }

  // write optional plaintext region
  if ( FBin.PlaintextOffset() > 0 )
    {
      assert(FBin.PlaintextOffset() <= FBin.Size());
      memcpy(p, FBin.RoData(), FBin.PlaintextOffset());
      p += FBin.PlaintextOffset();
    }

  ui32_t ct_size = FBin.Size() - FBin.PlaintextOffset();
  ui32_t diff = ct_size % CBC_BLOCK_SIZE;
  ui32_t block_size = ct_size - diff;
  assert((block_size % CBC_BLOCK_SIZE) == 0);

  // encrypt the ciphertext region essence data
  if ( ASDCP_SUCCESS(result) )
    {
      result = Ctx->EncryptBlock(FBin.RoData() + FBin.PlaintextOffset(), p, block_size);
      p += block_size;
    }

  // construct and encrypt the padding
  if ( ASDCP_SUCCESS(result) )
    {
      byte_t the_last_block[CBC_BLOCK_SIZE];

      if ( diff > 0 )
	memcpy(the_last_block, FBin.RoData() + FBin.PlaintextOffset() + block_size, diff);

      for (ui32_t i = 0; diff < CBC_BLOCK_SIZE; diff++, i++ )
	the_last_block[diff] = i;

      result = Ctx->EncryptBlock(the_last_block, p, CBC_BLOCK_SIZE);
    }

  if ( ASDCP_SUCCESS(result) )
    FBout.Size(calc_esv_length(FBin.Size(), FBin.PlaintextOffset()));

  return result;
}