/// <summary>
/// <para>Decrypts encrypted binary data, using specified symmetric algorithm.</para>
/// </summary>
/// <param name="self">Symmetric algorithm which have been used for encryption previously and should be used for decryption now.</param>
/// <param name="source">Binary data to be decrypted.</param>
/// <returns>Decrypted binary data.</returns>
/// <exception cref="ArgumentNullException">If either <paramref name="self"/> or <paramref name="source"/> is a <c>null</c> reference.</exception>
/// <seealso cref="Decrypt(SymmetricAlgorithm, Stream, bool)"/>
public static byte[] Decrypt(this SymmetricAlgorithm self, byte[] source)
{
Assertion.NotNull(self);
Assertion.NotNull(source);
return self.CreateDecryptor().TransformFinalBlock(source, 0, source.Length);
}
public static byte[] Decrypt(this SymmetricAlgorithm algorithm, byte[] inputBuffer)
{
using (var decryptor = algorithm.CreateDecryptor())
{
return decryptor.TransformFinalBlock(inputBuffer);
}
}
internal static byte[] Decrypt(this SymmetricAlgorithm alg, byte[] cipher, int blockSizeMultipler = 1)
{
using (ICryptoTransform decryptor = alg.CreateDecryptor())
{
return decryptor.Transform(cipher, blockSizeMultipler);
}
}
public static Byte[] Decrypt(this AesManaged aes, Byte[] source, Byte[] key, Byte[] iv)
{
var bytesKey = ResizeBytesArray(key, aes.Key.Length);
var bytesIv = ResizeBytesArray(iv, aes.IV.Length);
using (var msIn = new MemoryStream(source))
using (var cryptStreem = new CryptoStream(msIn, aes.CreateDecryptor(bytesKey, bytesIv), CryptoStreamMode.Read))
{
MemoryStream m = new MemoryStream();
cryptStreem.CopyTo(m);
return m.ToArray();
}
}
public static string DecryptString(this SymmetricAlgorithm algorithm, string ciphertext)
{
if (string.IsNullOrEmpty(ciphertext))
throw new ArgumentNullException("ciphertext");
var decryptor = algorithm.CreateDecryptor();
var bytes = Convert.FromBase64String(ciphertext);
var ms = new MemoryStream(bytes);
var cs = new CryptoStream(ms, decryptor, CryptoStreamMode.Read);
using (var reader = new StreamReader(cs))
{
return reader.ReadToEnd();
}
}
/// <summary>
/// Dencryptors the specified algorithm.
/// </summary>
/// <param name="algorithm">The algorithm.</param>
/// <param name="data">The data.</param>
/// <param name="offset">The offset.</param>
/// <param name="count">The count.</param>
/// <returns></returns>
public static byte[] Dencryptor(this SymmetricAlgorithm algorithm, byte[] data, int offset, int count)
{
MemoryStream tmp = new MemoryStream(data);
tmp.Position = 0;
System.Security.Cryptography.CryptoStream cryptoStream = new CryptoStream(tmp, algorithm.CreateDecryptor(), CryptoStreamMode.Read);
MemoryStream ms = new MemoryStream();
byte[] buffer = new byte[1024];
int readCount = -1;
do
{
readCount = cryptoStream.Read(buffer, 0, 1024);
ms.Write(buffer, 0, readCount);
}
while (readCount != 0);
return ms.ToArray();
}
public static byte[] Decrypt(this SymmetricAlgorithm algorithm, byte[] input)
{
// Create memory stream to which from read decrypted data.
using (var memoryStream = new MemoryStream(input))
{
//// Ensure that crypto operations are thread-safe.
//lock (algorithm)
//{
using (var transform = algorithm.CreateDecryptor())
{
var cryptoStream = new CryptoStream(memoryStream, transform, CryptoStreamMode.Read);
// Read output data to crypto stream.
byte[] output = new byte[input.Length];
int outputLength = cryptoStream.Read(output, 0, output.Length);
Array.Resize(ref output, outputLength);
// Return decrypted data.
return output;
}
//}
}
}
/// <summary>
/// Decrypts input stream onto output stream for the given parameters.
/// </summary>
/// <param name="algorithm"><see cref="SymmetricAlgorithm"/> to use for decryption.</param>
/// <param name="source">Source stream that contains data to decrypt.</param>
/// <param name="destination">Destination stream used to hold decrypted data.</param>
/// <param name="key">The secret key to use for the symmetric algorithm.</param>
/// <param name="iv">The initialization vector to use for the symmetric algorithm.</param>
public static void Decrypt(this SymmetricAlgorithm algorithm, Stream source, Stream destination, byte[] key, byte[] iv)
{
byte[] buffer = new byte[Standard.BufferSize];
CryptoStream decodeStream = new CryptoStream(destination, algorithm.CreateDecryptor(key, iv), CryptoStreamMode.Write);
int read;
// Decrypts data onto output stream.
read = source.Read(buffer, 0, Standard.BufferSize);
while (read > 0)
{
decodeStream.Write(buffer, 0, read);
read = source.Read(buffer, 0, Standard.BufferSize);
}
decodeStream.FlushFinalBlock();
}
/// <summary>Decrypts input stream onto output stream for the given parameters.</summary>
public static void Decrypt(this SymmetricAlgorithm algorithm, Stream inStream, Stream outStream, byte[] key, byte[] IV)
{
// This is the root decryption function. Eventually, all the symmetric algorithm based decryption
// functions perform their actual decryption here.
byte[] rgbKey = algorithm.GetLegalKey(key);
byte[] rgbIV = algorithm.GetLegalIV(IV);
byte[] buffer = new byte[BufferSize];
CryptoStream decodeStream = new CryptoStream(outStream, algorithm.CreateDecryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
int read;
// Decrypts data onto output stream.
read = inStream.Read(buffer, 0, BufferSize);
while (read > 0)
{
decodeStream.Write(buffer, 0, read);
read = inStream.Read(buffer, 0, BufferSize);
}
decodeStream.FlushFinalBlock();
}
public static ICryptoTransform CreateDecryptor(this SymmetricAlgorithm symmetricAlgorithm, CryptoKey cryptoKey, CryptoIV cryptoIV)
{
return symmetricAlgorithm.CreateDecryptor(cryptoKey.Value, cryptoIV.Value);
}
