internal BCryptSymmetricCryptoTransform(SafeBCryptAlgorithmHandle algorithm,
byte[] key,
byte[] iv,
PaddingMode paddingMode,
bool encrypting)
{
Debug.Assert(algorithm != null, "algorithm != null");
Debug.Assert(!algorithm.IsClosed && !algorithm.IsInvalid, "!algorithm.IsClosed && !algorithm.IsInvalid");
Debug.Assert(key != null, "key != null");
m_algorithm = algorithm;
m_encrypting = encrypting;
m_paddingMode = BlockPaddingMethod.Create(paddingMode,
BCryptNative.GetInt32Property(algorithm, BCryptNative.ObjectPropertyName.BlockLength));
m_iv = ProcessIV(iv, BCryptNative.GetInt32Property(algorithm,
BCryptNative.ObjectPropertyName.BlockLength),
BCryptNative.MapChainingMode(BCryptNative.GetStringProperty(algorithm, BCryptNative.ObjectPropertyName.ChainingMode)));
m_key = BCryptNative.ImportSymmetricKey(algorithm, key);
}
private SafeBCryptAlgorithmHandle SetupAlgorithm()
{
SafeBCryptAlgorithmHandle algorithmHandle = BCryptNative.OpenAlgorithm(m_algorithm.Algorithm, m_algorithmProvider.Provider);
// If we've selected a different block size than the default, set that now
if (BlockSize / 8 != BCryptNative.GetInt32Property(algorithmHandle, BCryptNative.ObjectPropertyName.BlockLength))
{
BCryptNative.SetInt32Property(algorithmHandle, BCryptNative.ObjectPropertyName.BlockLength, BlockSize / 8);
}
BCryptNative.SetStringProperty(algorithmHandle, BCryptNative.ObjectPropertyName.ChainingMode, BCryptNative.MapChainingMode(Mode));
return(algorithmHandle);
}