namespace Pwd
{
using System;
using System.Reflection;
using System.Text;
using System.Web.Configuration;
using System.Web.Security;

public class Crypto
{
public Crypto()
{
}

// Fields
private MethodInfo _EncDecMethod = null;

// Methods
public string Decrypt(string data)
{
string str;
Initialize();
try
{
byte [] buffer = Convert.FromBase64String(data);
object [] parameters = new object [5] ;
parameters [0] = false;
parameters [1] = buffer;
parameters [3] = 0;
parameters [4] = buffer.Length;
byte [] bytes = (byte [] )_EncDecMethod.Invoke(null, parameters);
str = Encoding.UTF8.GetString(bytes);
}
catch
{
throw new Exception("Failed to encrypt data.");
}
return str;
}

public string Encrypt(byte [] bytes)
{
string str = "";
Initialize();
try
{
object [] parameters = new object [5] ;
parameters [0] = true;
parameters [1] = bytes;
parameters [3] = 0;
parameters [4] = bytes.Length;
byte [] inArray = (byte [] )_EncDecMethod.Invoke(null, parameters);
str = Convert.ToBase64String(inArray);
}
catch
{
throw new Exception("Failed to encrypt data.");
}
return str;
}

private void Initialize()
{
try
{
_EncDecMethod = typeof(MachineKeySection).GetMethod("EncryptOrDecryptData",
BindingFlags.NonPublic | BindingFlags.Static,
Type.DefaultBinder,
new Type [] { typeof(bool), typeof(byte [] ), typeof(byte [] ), typeof(int), typeof(int) }, null);
}
catch
{
throw new Exception("Failed to initialized base encryption method.");
}
}

public string Encode(string pass, string salt)
{
byte [] bytes = Encoding.Unicode.GetBytes(pass);
byte [] src = Convert.FromBase64String(salt);
byte [] data = new byte [src.Length + bytes.Length] ;
Buffer.BlockCopy(src, 0, data, 0, src.Length);
Buffer.BlockCopy(bytes, 0, data, src.Length, bytes.Length);

string s = Encrypt(data);
return s;
}
}
}