private int EncryptData(byte[] inputBuffer, int inputOffset, int inputCount, ref byte[] outputBuffer,
int outputOffset, PaddingMode paddingMode, bool final)
{
if (inputBuffer.Length < (inputOffset + inputCount))
{
throw new CryptographicException();
}
int inputBlockSize = InputBlockSize;
int blockSizeBytes = BlockSizeBytes;
ExtendedCipherMode mode = Mode;
int partialBlockSize = inputCount % inputBlockSize;
int paddingSizeRequired = 0;
byte[] data;
if (final)
{
switch (paddingMode)
{
case PaddingMode.None:
if (partialBlockSize != 0 & !Utils.IsStreamMode(mode))
{
throw new CryptographicException();
}
break;
case PaddingMode.PKCS7:
paddingSizeRequired = inputBlockSize - partialBlockSize;
break;
case PaddingMode.Zeros:
if (partialBlockSize != 0)
{
paddingSizeRequired = inputBlockSize - partialBlockSize;
}
break;
case PaddingMode.ANSIX923:
paddingSizeRequired = inputBlockSize - partialBlockSize;
break;
case PaddingMode.ISO10126:
paddingSizeRequired = inputBlockSize - partialBlockSize;
break;
}
if (paddingSizeRequired != 0)
{
data = new byte[paddingSizeRequired];
switch (paddingMode)
{
case PaddingMode.PKCS7:
int index = 0;
while (index < paddingSizeRequired)
{
data[index] = (byte)paddingSizeRequired;
index++;
}
break;
case PaddingMode.ANSIX923:
data[paddingSizeRequired - 1] = (byte)paddingSizeRequired;
break;
case PaddingMode.ISO10126:
Utils.RandomNumberGeneratorSingleton.GetBytes(data);
data[paddingSizeRequired - 1] = (byte)paddingSizeRequired;
break;
}
var tempBuffer = new byte[inputCount + paddingSizeRequired];
Array.Copy(inputBuffer, 0, tempBuffer, 0, inputCount);
data.CopyTo(tempBuffer, inputCount);
inputBuffer = tempBuffer;
}
}
if (outputBuffer == null)
{
outputBuffer = new byte[inputCount + paddingSizeRequired];
outputOffset = 0;
}
else if ((outputBuffer.Length - outputOffset) < (inputCount + paddingSizeRequired))
{
throw new CryptographicException();
}
int byteCount = 0;
var tempState = new byte[blockSizeBytes];
int count = blockSizeBytes;
if (mode == ExtendedCipherMode.CFB)
{
count = _registerShiftSize == 0 ? 1 : _registerShiftSize;
}
while (byteCount < inputCount + paddingSizeRequired)
{
var block = new byte[blockSizeBytes];
int bytesToCopy = count;
if (blockSizeBytes + inputOffset > inputBuffer.Length)
{
bytesToCopy = inputBuffer.Length - inputOffset;
}
Array.Copy(inputBuffer, inputOffset, block, 0, bytesToCopy);
switch (mode)
{
case ExtendedCipherMode.ECB:
EncryptBlock(block);
break;
case ExtendedCipherMode.CBC:
for (int i = 0; i < blockSizeBytes; i++)
{
block[i] ^= _feedbackValue[i];
}
EncryptBlock(block);
block.CopyTo(_feedbackValue, 0);
break;
case ExtendedCipherMode.CFB:
Array.Copy(_feedbackValue, count, tempState, 0, blockSizeBytes - count);
EncryptBlock(_feedbackValue);
for (int i = 0; i < count; i++)
{
_feedbackValue[i] ^= block[i];
}
Array.Copy(_feedbackValue, 0, block, 0, count);
tempState.CopyTo(_feedbackValue, 0);
Array.Copy(block, 0, _feedbackValue, blockSizeBytes - count, count);
break;
case ExtendedCipherMode.OFB:
Array.Copy(_feedbackValue, count, tempState, 0, blockSizeBytes - count);
EncryptBlock(_feedbackValue);
for (int i = 0; i < count; i++)
{
block[i] ^= _feedbackValue[i];
}
Array.Copy(_feedbackValue, 0, _feedbackValue, blockSizeBytes - count, count);
Array.Copy(tempState, 0, _feedbackValue, 0, blockSizeBytes - count);
break;
case ExtendedCipherMode.CTS:
throw new NotImplementedException();
case ExtendedCipherMode.CTR:
if (_initial)
{
_initial = false;
}
else
{
IncrementCounter();
}
switch (NonceCombinationMode)
{
case NonceCombinationMode.Concatenate:
_iv.CopyTo(_feedbackValue, 0);
_counter.CopyTo(_feedbackValue, blockSizeBytes - _counterSize);
break;
case NonceCombinationMode.Add:
_counter.CopyTo(_feedbackValue, 0);
break;
case NonceCombinationMode.Xor:
_iv.CopyTo(_feedbackValue, 0);
for (int index = 0; index < _counterSize; index++)
{
_feedbackValue[blockSizeBytes - _counterSize + index] ^= _counter[index];
}
break;
}
EncryptBlock(_feedbackValue);
for (int i = 0; i < blockSizeBytes; i++)
{
block[i] ^= _feedbackValue[i];
}
break;
}
if (outputOffset + count > outputBuffer.Length)
{
count = outputBuffer.Length - outputOffset;
}
Array.Copy(block, 0, outputBuffer, outputOffset, count);
byteCount += count;
inputOffset += count;
outputOffset += count;
}
if (Utils.IsStreamMode(mode) && outputBuffer.Length > inputCount && paddingMode == PaddingMode.None)
{
var result = new byte[inputCount];
Array.Copy(outputBuffer, 0, result, 0, inputCount);
outputBuffer = result;
}
return(inputCount);
}
static internal bool IsStreamMode(ExtendedCipherMode mode)
{
return(mode == ExtendedCipherMode.CFB || mode == ExtendedCipherMode.OFB || mode == ExtendedCipherMode.CTR);
}
internal static ICryptoTransform NewEncryptor(ISymmetricAlgorithm algorithm, Type type, byte[] rgbKey, ExtendedCipherMode mode, byte[] rgbIv, TransformDirection encryptDirection)
{
if (rgbKey == null)
{
rgbKey = algorithm.GenerateNonWeakKey();
}
if ((mode != ExtendedCipherMode.ECB) && (rgbIv == null))
{
rgbIv = new byte[algorithm.BlockSize / 8];
RandomNumberGeneratorSingleton.GetBytes(rgbIv);
}
ConstructorInfo constructor = type.GetConstructor(BindingFlags.Instance | BindingFlags.NonPublic, null,
new[] { typeof(ISymmetricAlgorithm), typeof(byte[]), typeof(byte[]),
typeof(TransformDirection)}, null);
return (ICryptoTransform)constructor.Invoke(new object[] {algorithm, rgbKey, rgbIv, encryptDirection});
//return (ICryptoTransform)Activator.CreateInstance(type, BindingFlags.NonPublic, null, new object[] { algorithm, rgbKey, rgbIv, encryptDirection }, null);
}
static internal ICryptoTransform NewEncryptor(ISymmetricAlgorithm algorithm, Type type, byte[] rgbKey, ExtendedCipherMode mode, byte[] rgbIv, TransformDirection encryptDirection)
{
if (rgbKey == null)
{
rgbKey = algorithm.GenerateNonWeakKey();
}
if ((mode != ExtendedCipherMode.ECB) && (rgbIv == null))
{
rgbIv = new byte[algorithm.BlockSize / 8];
RandomNumberGeneratorSingleton.GetBytes(rgbIv);
}
ConstructorInfo constructor = type.GetConstructor(BindingFlags.Instance | BindingFlags.NonPublic, null,
new[] { typeof(ISymmetricAlgorithm), typeof(byte[]), typeof(byte[]),
typeof(TransformDirection) }, null);
return((ICryptoTransform)constructor.Invoke(new object[] { algorithm, rgbKey, rgbIv, encryptDirection }));
//return (ICryptoTransform)Activator.CreateInstance(type, BindingFlags.NonPublic, null, new object[] { algorithm, rgbKey, rgbIv, encryptDirection }, null);
}
internal static bool IsStreamMode(ExtendedCipherMode mode)
{
return mode == ExtendedCipherMode.CFB || mode == ExtendedCipherMode.OFB || mode == ExtendedCipherMode.CTR;
}
