//
// Overrides
//
protected override Stream CreateCryptoStream(Stream stream, AlgorithmKey key)
{
SymmetricAlgorithm algo = AlgorithmProvider.Create(this.Algorithm);
ICryptoTransform transform = algo.CreateDecryptor(key.Key, key.IV);
//
// CryptoStream is not seekable, and BizTalk doesn't like that
// We'll get a "Stream does not support seeking." error
// at runtime. So we decrypt into an in-memory buffer
// and then give BizTalk that instead.
//
Stream cryptoStream = new CryptoStream(stream, transform, CryptoStreamMode.Read);
using ( cryptoStream ) {
MemoryStream memStream = new MemoryStream();
byte[] buffer = new byte[1024 * 64];
int bytes = 0;
do {
bytes = cryptoStream.Read(buffer, 0, buffer.Length);
memStream.Write(buffer, 0, bytes);
} while ( bytes > 0 );
memStream.Position = 0;
return memStream;
}
}
//
// Overrides
//
protected override Stream CreateCryptoStream(Stream stream, AlgorithmKey key)
{
SymmetricAlgorithm algo = AlgorithmProvider.Create(this.Algorithm);
ICryptoTransform transform = algo.CreateEncryptor(key.Key, key.IV);
return new CryptoStream(stream, transform, CryptoStreamMode.Read);
}
// // Overridable Methods // /// <summary> /// Creates the crypto stream used to encrypt/decrypt the message /// </summary> /// <param name="stream"></param> /// <param name="key"></param> /// <returns></returns> protected abstract Stream CreateCryptoStream(Stream stream, AlgorithmKey key);