protected virtual CryptoStream CreateDecryptingStream(
Stream encryptedStream)
{
if (encryptedStream == null)
{
throw new ArgumentNullException(nameof(encryptedStream));
}
if (!encryptedStream.CanRead)
{
throw new ArgumentException(Resources.StreamNotReadable, nameof(encryptedStream));
}
if (!IsSymmetricKeyInitialized)
{
throw new InvalidOperationException(Resources.UninitializedSymmetricKey);
}
return(new CryptoStream(
encryptedStream,
Symmetric.CreateDecryptor(),
CryptoStreamMode.Read));
}