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;
}
}
}