| public CreateDecryptor ( byte key, byte iv ) : ICryptoTransform | ||
| key | byte | A byte array that contains a key. The length of this key should be equal to the KeySize property |
| iv | byte | A byte array that contains an initialization vector. The length of this IV should be equal to the BlockSize property |
| Résultat | ICryptoTransform | |
public byte[] Decrypt(byte[] file)
{
Twofish fish = new Twofish();
fish.Mode = CipherMode.ECB;
byte[] dummy = { };
//create Twofish Decryptor from our twofish instance
ICryptoTransform decrypt = fish.CreateDecryptor(key, dummy);
System.IO.MemoryStream msD = new System.IO.MemoryStream();
//create crypto stream set to read and do a Twofish decryption transform on incoming bytes
CryptoStream cryptostreamDecr = new CryptoStream(msD, decrypt, CryptoStreamMode.Write);
//write out Twofish encrypted stream
cryptostreamDecr.Write(file, 0, file.Length);
cryptostreamDecr.Close();
byte[] buf = msD.GetBuffer();
// TODO: It might be pretty dangerous to cut on the size of the input buffer
// because of the padding some bytes might be added. However these bytes will
// be only zeros (External.Twofish uses Padding.Zero) so zeros should be OK.
Array.Resize(ref buf, file.Length);
// We can not remove any other padding bytes because we can not distinuish between
// bytes added by the crypto algo and bytes belonging to the original unecrtypted file.
return buf;
}
public string Decrypt(string encrypted_str)
{
Twofish fish = new Twofish();
fish.Mode = CipherMode.ECB;
byte[] plainText = {};
//create Twofish Decryptor from our twofish instance
ICryptoTransform decrypt = fish.CreateDecryptor(key, plainText);
System.IO.MemoryStream msD = new System.IO.MemoryStream();
//create crypto stream set to read and do a Twofish decryption transform on incoming bytes
CryptoStream cryptostreamDecr = new CryptoStream(msD, decrypt, CryptoStreamMode.Write);
byte[] bytOut = GetBytes(encrypted_str);
//write out Twofish encrypted stream
cryptostreamDecr.Write(bytOut, 0, bytOut.Length);
cryptostreamDecr.Close();
byte[] bytOutD = msD.GetBuffer();
return GetString(bytOutD);
}
static void Main(string[] args)
{
Twofish fish = new Twofish();
fish.Mode = CipherMode.ECB;
System.IO.MemoryStream ms = new System.IO.MemoryStream();
byte[] Key = {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16};
byte[] dummy = {};
//create Twofish Encryptor from this instance
ICryptoTransform encrypt = fish.CreateEncryptor(Key, dummy); // we use the plainText as the IV as in ECB mode the IV is not used
//Create Crypto Stream that transforms file stream using twofish encryption
CryptoStream cryptostream = new CryptoStream(ms, encrypt, CryptoStreamMode.Write);
byte[] plainText = GetBytes("Some string to encrypt");
//write out Twofish encrypted stream
cryptostream.Write(plainText, 0, plainText.Length);
cryptostream.Close();
byte[] bytOut = ms.ToArray();
System.Console.WriteLine( "Encrypted string: " + GetString( bytOut ) );
//create Twofish Decryptor from our twofish instance
ICryptoTransform decrypt = fish.CreateDecryptor(Key, plainText);
System.IO.MemoryStream msD = new System.IO.MemoryStream();
//create crypto stream set to read and do a Twofish decryption transform on incoming bytes
CryptoStream cryptostreamDecr = new CryptoStream(msD, decrypt, CryptoStreamMode.Write);
//write out Twofish encrypted stream
cryptostreamDecr.Write(bytOut, 0, bytOut.Length);
cryptostreamDecr.Close();
byte[] bytOutD = msD.GetBuffer();
System.Console.WriteLine("Decrypted string: " + GetString(bytOutD));
}
public string shadow_decrypt(string encyptedText)
{
fish = new Twofish();
fish.Mode = CipherMode.ECB;
ms = new System.IO.MemoryStream();
//form.log("we were sent the IM with " + encyptedText);
byte[] encyptedBytes = Utils.StringToBytes(encyptedText);
ICryptoTransform decode = new FromBase64Transform();
//create DES Decryptor from our des instance
ICryptoTransform decrypt = fish.CreateDecryptor(form.getKey(), encyptedBytes);
System.IO.MemoryStream msD = new System.IO.MemoryStream();
CryptoStream cryptostreamDecode = new CryptoStream(new CryptoStream(msD,decrypt,CryptoStreamMode.Write),decode,CryptoStreamMode.Write);
cryptostreamDecode.Write(encyptedBytes, 0, encyptedBytes.Length);
cryptostreamDecode.Close();
byte[] bytOutD = msD.ToArray(); // we should now have our plain text back
form.log("We decrypted "+encyptedText+" to " + Utils.BytesToString(bytOutD),Color.Red);
return ""+this.indicator+""+Utils.BytesToString(bytOutD);
}