size_t Put2(const byte *inString, size_t length, int messageEnd, bool blocking)
{
FILTER_BEGIN;
m_ciphertextQueue.Put(inString, length);
if (messageEnd)
{
{
size_t ciphertextLength;
if (!SafeConvert(m_ciphertextQueue.CurrentSize(), ciphertextLength))
throw InvalidArgument("PK_DefaultDecryptionFilter: ciphertext too long");
size_t maxPlaintextLength = m_decryptor.MaxPlaintextLength(ciphertextLength);
SecByteBlock ciphertext(ciphertextLength);
m_ciphertextQueue.Get(ciphertext, ciphertextLength);
m_plaintext.resize(maxPlaintextLength);
m_result = m_decryptor.Decrypt(m_rng, ciphertext, ciphertextLength, m_plaintext, m_parameters);
if (!m_result.isValidCoding)
throw InvalidCiphertext(m_decryptor.AlgorithmName() + ": invalid ciphertext");
}
FILTER_OUTPUT(1, m_plaintext, m_result.messageLength, messageEnd);
}
FILTER_END_NO_MESSAGE_END;
}
unsigned int Put2(const byte *inString, unsigned int length, int messageEnd, bool blocking)
{
FILTER_BEGIN;
m_ciphertextQueue.Put(inString, length);
if (messageEnd)
{
{
unsigned int ciphertextLength = m_ciphertextQueue.CurrentSize();
unsigned int maxPlaintextLength = m_decryptor.MaxPlaintextLength(ciphertextLength);
SecByteBlock ciphertext(ciphertextLength);
m_ciphertextQueue.Get(ciphertext, ciphertextLength);
m_plaintext.resize(maxPlaintextLength);
m_result = m_decryptor.Decrypt(m_rng, ciphertext, ciphertextLength, m_plaintext, m_parameters);
if (!m_result.isValidCoding)
throw InvalidCiphertext(m_decryptor.AlgorithmName() + ": invalid ciphertext");
}
FILTER_OUTPUT(1, m_plaintext, m_result.messageLength, messageEnd);
}
FILTER_END_NO_MESSAGE_END;
}
bool IsolatedMessageEnd(bool blocking)
{
switch (m_continueAt)
{
case 0:
{
unsigned int ciphertextLength = m_inQueue.CurrentSize();
unsigned int maxPlaintextLength = m_decryptor.MaxPlaintextLength(ciphertextLength);
SecByteBlock ciphertext(ciphertextLength);
m_inQueue.Get(ciphertext, ciphertextLength);
m_plaintext.resize(maxPlaintextLength);
m_result = m_decryptor.Decrypt(ciphertext, ciphertextLength, m_plaintext);
if (!m_result.isValidCoding)
throw InvalidCiphertext(m_decryptor.AlgorithmName() + ": invalid ciphertext");
}
case 1:
if (!Output(1, m_plaintext, m_result.messageLength, 0, blocking))
return false;
}
return true;
}
void StreamTransformationFilter::LastPut(const byte *inString, size_t length)
{
byte *space = NULL;
switch (m_padding)
{
case NO_PADDING:
case ZEROS_PADDING:
if (length > 0)
{
size_t minLastBlockSize = m_cipher.MinLastBlockSize();
bool isForwardTransformation = m_cipher.IsForwardTransformation();
if (isForwardTransformation && m_padding == ZEROS_PADDING && (minLastBlockSize == 0 || length < minLastBlockSize))
{
// do padding
size_t blockSize = STDMAX(minLastBlockSize, (size_t)m_cipher.MandatoryBlockSize());
space = HelpCreatePutSpace(*AttachedTransformation(), DEFAULT_CHANNEL, blockSize);
if (inString) {memcpy(space, inString, length);}
memset(space + length, 0, blockSize - length);
m_cipher.ProcessLastBlock(space, space, blockSize);
AttachedTransformation()->Put(space, blockSize);
}
else
{
if (minLastBlockSize == 0)
{
if (isForwardTransformation)
throw InvalidDataFormat("StreamTransformationFilter: plaintext length is not a multiple of block size and NO_PADDING is specified");
else
throw InvalidCiphertext("StreamTransformationFilter: ciphertext length is not a multiple of block size");
}
space = HelpCreatePutSpace(*AttachedTransformation(), DEFAULT_CHANNEL, length, m_optimalBufferSize);
m_cipher.ProcessLastBlock(space, inString, length);
AttachedTransformation()->Put(space, length);
}
}
break;
case PKCS_PADDING:
case ONE_AND_ZEROS_PADDING:
unsigned int s;
s = m_cipher.MandatoryBlockSize();
assert(s > 1);
space = HelpCreatePutSpace(*AttachedTransformation(), DEFAULT_CHANNEL, s, m_optimalBufferSize);
if (m_cipher.IsForwardTransformation())
{
assert(length < s);
if (inString) {memcpy(space, inString, length);}
if (m_padding == PKCS_PADDING)
{
assert(s < 256);
byte pad = byte(s-length);
memset(space+length, pad, s-length);
}
else
{
space[length] = 0x80;
memset(space+length+1, 0, s-length-1);
}
m_cipher.ProcessData(space, space, s);
AttachedTransformation()->Put(space, s);
}
else
{
if (length != s)
throw InvalidCiphertext("StreamTransformationFilter: ciphertext length is not a multiple of block size");
m_cipher.ProcessData(space, inString, s);
if (m_padding == PKCS_PADDING)
{
byte pad = space[s-1];
if (pad < 1 || pad > s || std::find_if(space+s-pad, space+s, std::bind2nd(std::not_equal_to<byte>(), pad)) != space+s)
throw InvalidCiphertext("StreamTransformationFilter: invalid PKCS #7 block padding found");
length = s-pad;
}
else
{
while (length > 1 && space[length-1] == 0)
--length;
if (space[--length] != 0x80)
throw InvalidCiphertext("StreamTransformationFilter: invalid ones-and-zeros padding found");
}
AttachedTransformation()->Put(space, length);
}
break;
default:
assert(false);
}
}
