public byte[] DecryptKeyExchange(byte[] data)
{
if (m_Disposed)
{
throw new CryptographicException("The key has been disposed");
}
if (m_NeedsHack)
{
// get the key handle
IntPtr key = GetHandle(m_Key);
// decrypt the data
byte[] dec = (byte[])data.Clone();
Array.Reverse(dec); // big endian to little endian
int size = data.Length;
if (SspiProvider.CryptDecrypt(key, 0, 1, 0, dec, ref size) == 0)
{
throw new CryptographicException("Unable to decrypt the key exchange [" + Marshal.GetLastWin32Error() + "].");
}
byte[] ret = new byte[size];
Buffer.BlockCopy(dec, 0, ret, 0, size);
return(ret);
}
else
{
return(m_Key.Decrypt(data, false));
}
}
/// <summary>
/// Transforms the specified region of the input byte array and copies the resulting transform to the specified region of the output byte array.
/// </summary>
/// <param name="inputBuffer">The input for which to compute the transform.</param>
/// <param name="inputOffset">The offset into the input byte array from which to begin using data.</param>
/// <param name="inputCount">The number of bytes in the input byte array to use as data.</param>
/// <param name="outputBuffer">The output to which to write the transform.</param>
/// <param name="outputOffset">The offset into the output byte array from which to begin writing data.</param>
/// <returns>The number of bytes written.</returns>
/// <exception cref="ObjectDisposedException">The object has been disposed.</exception>
/// <exception cref="ArgumentNullException"><paramref name="inputBuffer"/> or <paramref name="outputBuffer"/> is a null reference (<b>Nothing</b> in Visual Basic).</exception>
/// <exception cref="ArgumentOutOfRangeException">One of the specified offsets or lengths is invalid.</exception>
/// <exception cref="CryptographicException">An error occurs while transforming the specified data.</exception>
public int TransformBlock(byte[] inputBuffer, int inputOffset, int inputCount, byte[] outputBuffer, int outputOffset)
{
if (m_Key == null)
{
throw new ObjectDisposedException(this.GetType().FullName);
}
if (inputBuffer == null || outputBuffer == null)
{
throw new ArgumentNullException();
}
if (inputCount < 0 || inputOffset < 0 || outputOffset < 0 || inputOffset + inputCount > inputBuffer.Length)
{
throw new ArgumentOutOfRangeException();
}
int length = inputCount;
if (m_Method == CryptoMethod.Encrypt)
{
if (SspiProvider.CryptEncrypt(m_Key.Handle, 0, 0, 0, null, ref length, 0) == 0)
{
throw new CryptographicException("Could not encrypt data.");
}
if (outputBuffer.Length - outputOffset < length)
{
throw new ArgumentOutOfRangeException();
}
Buffer.BlockCopy(inputBuffer, inputOffset, outputBuffer, outputOffset, inputCount);
length = inputCount;
GCHandle h = GCHandle.Alloc(outputBuffer, GCHandleType.Pinned);
try {
if (SspiProvider.CryptEncrypt(m_Key.Handle, 0, 0, 0, new IntPtr(h.AddrOfPinnedObject().ToInt64() + outputOffset), ref length, outputBuffer.Length - outputOffset) == 0)
{
throw new CryptographicException("Could not encrypt data.");
}
} finally {
h.Free();
}
}
else // decrypt
{
byte[] orgCopy = new byte[inputCount];
Buffer.BlockCopy(inputBuffer, inputOffset, orgCopy, 0, inputCount);
if (SspiProvider.CryptDecrypt(m_Key.Handle, 0, 0, 0, orgCopy, ref length) == 0)
{
throw new CryptographicException("Could not decrypt data.");
}
if (length > outputBuffer.Length - outputOffset)
{
throw new ArgumentOutOfRangeException();
}
Buffer.BlockCopy(orgCopy, 0, outputBuffer, outputOffset, length);
}
return(length);
}
/// <summary>
/// Transforms the specified region of the specified byte array.
/// </summary>
/// <param name="inputBuffer">The input for which to compute the transform.</param>
/// <param name="inputOffset">The offset into the byte array from which to begin using data.</param>
/// <param name="inputCount">The number of bytes in the byte array to use as data.</param>
/// <returns>The computed transform.</returns>
/// <exception cref="ObjectDisposedException">The object has been disposed.</exception>
/// <exception cref="ArgumentNullException"><paramref name="inputBuffer"/> is a null reference (<b>Nothing</b> in Visual Basic).</exception>
/// <exception cref="ArgumentOutOfRangeException">The combination of offset and length is invalid.</exception>
/// <exception cref="CryptographicException">An error occurs while transforming the specified data.</exception>
public byte[] TransformFinalBlock(byte[] inputBuffer, int inputOffset, int inputCount)
{
if (m_Key == null)
{
throw new ObjectDisposedException(this.GetType().FullName);
}
if (inputBuffer == null)
{
throw new ArgumentNullException();
}
if (inputCount < 0 || inputOffset < 0 || inputOffset + inputCount > inputBuffer.Length)
{
throw new ArgumentOutOfRangeException();
}
int length = inputCount;
byte[] ret;
if (m_Method == CryptoMethod.Encrypt)
{
if (SspiProvider.CryptEncrypt(m_Key.Handle, 0, 1, 0, null, ref length, 0) == 0)
{
throw new CryptographicException("Could not encrypt data.");
}
ret = new byte[length];
Buffer.BlockCopy(inputBuffer, inputOffset, ret, 0, inputCount);
length = inputCount;
if (SspiProvider.CryptEncrypt(m_Key.Handle, 0, 1, 0, ret, ref length, ret.Length) == 0)
{
throw new CryptographicException("Could not encrypt data.");
}
}
else // decrypt
{
byte[] orgCopy = new byte[inputCount];
Buffer.BlockCopy(inputBuffer, inputOffset, orgCopy, 0, inputCount);
if (SspiProvider.CryptDecrypt(m_Key.Handle, 0, 1, 0, orgCopy, ref length) == 0)
{
throw new CryptographicException("Could not decrypt data.");
}
ret = new byte[length];
Buffer.BlockCopy(orgCopy, 0, ret, 0, length);
}
return(ret);
}
