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|
class Program
{
static void Main(string[] args)
{
Program pr = new Program();
var test = pr.EncryptUsernamePassword("test");
var test2 = pr.DecryptUsernamePassword(test);
Console.ReadLine();
}
public string EncryptUsernamePassword(string clearText)
{
// TODO: Parameterize the Password, Salt, and Iterations. They should be encrypted with the machine key and stored in the registry
if (string.IsNullOrEmpty(clearText))
{
return clearText;
}
byte[] salt = {};
// NOTE: The keystring, salt, and iterations must be the same as what is used in the Demo java system.
PKCSKeyGenerator crypto = new PKCSKeyGenerator("MyPassword", salt, 20, 1);
ICryptoTransform cryptoTransform = crypto.Encryptor;
var cipherBytes = cryptoTransform.TransformFinalBlock(Encoding.UTF8.GetBytes(clearText), 0, clearText.Length);
return Convert.ToBase64String(cipherBytes);
}
public string DecryptUsernamePassword(string cipherText)
{
if (string.IsNullOrEmpty(cipherText))
{
return cipherText;
}
byte[] salt = {};
// NOTE: The keystring, salt, and iterations must be the same as what is used in the Demo java system.
PKCSKeyGenerator crypto = new PKCSKeyGenerator("MyPassword", salt, 20, 1);
ICryptoTransform cryptoTransform = crypto.Decryptor;
var cipherBytes = Convert.FromBase64String(cipherText);
var clearBytes = cryptoTransform.TransformFinalBlock(cipherBytes, 0, cipherBytes.Length);
return Encoding.UTF8.GetString(clearBytes);
}
}
}
public class PKCSKeyGenerator
{
private byte[] key = new byte[8];
private byte[] iv = new byte[8];
private DESCryptoServiceProvider des = new DESCryptoServiceProvider();
public PKCSKeyGenerator()
{
}
public PKCSKeyGenerator(string keystring, byte[] salt, int iterationsMd5, int segments)
{
this.Generate(keystring, salt, iterationsMd5, segments);
}
public byte[] Key
{
get
{
return this.key;
}
}
public byte[] IV
{
get
{
return this.iv;
}
}
public ICryptoTransform Encryptor
{
get
{
return this.des.CreateEncryptor(this.key, this.iv);
}
}
public ICryptoTransform Decryptor
{
get
{
return des.CreateDecryptor(key, iv);
}
}
public ICryptoTransform Generate(string keystring, byte[] salt, int iterationsMd5, int segments)
{
// MD5 bytes
int hashLength = 16;
// to store contatenated Mi hashed results
byte[] keyMaterial = new byte[hashLength * segments];
// --- get secret password bytes ----
byte[] passwordBytes;
passwordBytes = Encoding.UTF8.GetBytes(keystring);
// --- contatenate salt and pswd bytes into fixed data array ---
byte[] data00 = new byte[passwordBytes.Length + salt.Length];
// copy the pswd bytes
Array.Copy(passwordBytes, data00, passwordBytes.Length);
// concatenate the salt bytes
Array.Copy(salt, 0, data00, passwordBytes.Length, salt.Length);
// ---- do multi-hashing and contatenate results D1, D2 ... into keymaterial bytes ----
MD5 md5 = new MD5CryptoServiceProvider();
byte[] result = null;
// fixed length initial hashtarget
byte[] hashtarget = new byte[hashLength + data00.Length];
for (int j = 0; j < segments; j++)
{
// ---- Now hash consecutively for iterationsMd5 times ------
if (j == 0)
{
// initialize
result = data00;
}
else
{
Array.Copy(result, hashtarget, result.Length);
Array.Copy(data00, 0, hashtarget, result.Length, data00.Length);
result = hashtarget;
}
for (int i = 0; i < iterationsMd5; i++)
{
result = md5.ComputeHash(result);
}
// contatenate to keymaterial
Array.Copy(result, 0, keyMaterial, j * hashLength, result.Length);
}
Array.Copy(keyMaterial, 0, this.key, 0, 8);
Array.Copy(keyMaterial, 8, this.iv, 0, 8);
return this.Encryptor;
} |
