using System;

using System.IO;

using System.Security.Cryptography;

using System.Text;

​

public class Program

{

    public static void Main()

    {

        string test;

        test = CR.DS("yyEq0Uvvhq2uQOcWG8peLoeRQehqip/fKdeG/kjEVb4=");

        Console.WriteLine(test);

    }

    public class CR

  {

    private const string K = "667912";

    private const string I = "1L1SA61493DRV53Z";

    private const string SA = "1313Rf99";

​

    public static string DS(string EncryptedString)

    {

      return string.IsNullOrEmpty(EncryptedString) ? string.Empty : CR.RD(EncryptedString, "667912", "1313Rf99", 3, "1L1SA61493DRV53Z", 256);

    }

​

    public static string ES(string PlainString)

    {

      return string.IsNullOrEmpty(PlainString) ? string.Empty : CR.RE(PlainString, "667912", "1313Rf99", 3, "1L1SA61493DRV53Z", 256);

    }

​

    private static string RE(

      string plainText,

      string passPhrase,

      string saltValue,

      int passwordIterations,

      string initVector,

      int keySize)

    {

      byte[] bytes1 = Encoding.ASCII.GetBytes(initVector);

      byte[] bytes2 = Encoding.ASCII.GetBytes(saltValue);

      byte[] bytes3 = Encoding.ASCII.GetBytes(plainText);

      byte[] bytes4 = new Rfc2898DeriveBytes(passPhrase, bytes2, passwordIterations).GetBytes(checked ((int) Math.Round(unchecked ((double) keySize / 8.0))));

      AesCryptoServiceProvider cryptoServiceProvider = new AesCryptoServiceProvider();

      cryptoServiceProvider.Mode = CipherMode.CBC;

      ICryptoTransform encryptor = cryptoServiceProvider.CreateEncryptor(bytes4, bytes1);

      using (MemoryStream memoryStream = new MemoryStream())

      {

        using (CryptoStream cryptoStream = new CryptoStream((Stream) memoryStream, encryptor, CryptoStreamMode.Write))

        {

          cryptoStream.Write(bytes3, 0, bytes3.Length);

          cryptoStream.FlushFinalBlock();

          byte[] array = memoryStream.ToArray();

          memoryStream.Close();

          cryptoStream.Close();

          return Convert.ToBase64String(array);

        }

      }

    }

​

    private static string RD(

      string cipherText,

      string passPhrase,

      string saltValue,

      int passwordIterations,

      string initVector,

      int keySize)

    {

      byte[] bytes1 = Encoding.ASCII.GetBytes(initVector);

      byte[] bytes2 = Encoding.ASCII.GetBytes(saltValue);

      byte[] buffer = Convert.FromBase64String(cipherText);

      byte[] bytes3 = new Rfc2898DeriveBytes(passPhrase, bytes2, passwordIterations).GetBytes(checked ((int) Math.Round(unchecked ((double) keySize / 8.0))));

      AesCryptoServiceProvider cryptoServiceProvider = new AesCryptoServiceProvider();

      cryptoServiceProvider.Mode = CipherMode.CBC;

      ICryptoTransform decryptor = cryptoServiceProvider.CreateDecryptor(bytes3, bytes1);

      MemoryStream memoryStream = new MemoryStream(buffer);

      CryptoStream cryptoStream = new CryptoStream((Stream) memoryStream, decryptor, CryptoStreamMode.Read);

      byte[] numArray = new byte[checked (buffer.Length + 1)];

      int count = cryptoStream.Read(numArray, 0, numArray.Length);

      memoryStream.Close();

      cryptoStream.Close();

      return Encoding.ASCII.GetString(numArray, 0, count);

    }

  }

}