AES.cs Unity

using UnityEngine;
using System.Collections;
using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;
using System.Diagnostics;

public class AES : MonoBehaviour {

    private const string _SALT = "g46dzQ80";
    private const string _INITVECTOR = "OFRna74m*aze01xY";

    private static byte[] _saltBytes;
    private static byte[] _initVectorBytes;

    static AES()
    {
        _saltBytes = Encoding.UTF8.GetBytes(_SALT);
        _initVectorBytes = Encoding.UTF8.GetBytes(_INITVECTOR);
    }

    void Start(){
        //string enc = Encrypt ("thieumao","12345678");
        //Debug.Log ("ket qua: " + enc);
        //Debug.Log ("");
    }



    /// <summary>
    /// Encrypts a string with AES
    /// </summary>
    /// <param name="plainText">Text to be encrypted</param>
    /// <param name="password">Password to encrypt with</param>
    /// <param name="salt">Salt to encrypt with</param>
    /// <param name="initialVector">Needs to be 16 ASCII characters long</param>
    /// <returns>An encrypted string</returns>
    public static string Encrypt(string plainText, string password, string salt = null, string initialVector = null)
    {
        return Convert.ToBase64String(EncryptToBytes(plainText, password, salt, initialVector));
    }

    /// <summary>
    /// Encrypts a string with AES
    /// </summary>
    /// <param name="plainText">Text to be encrypted</param>
    /// <param name="password">Password to encrypt with</param>
    /// <param name="salt">Salt to encrypt with</param>
    /// <param name="initialVector">Needs to be 16 ASCII characters long</param>
    /// <returns>An encrypted string</returns>
    public static byte[] EncryptToBytes(string plainText, string password, string salt = null, string initialVector = null)
    {
        byte[] plainTextBytes = Encoding.UTF8.GetBytes(plainText);
        return EncryptToBytes(plainTextBytes, password, salt, initialVector);
    }

    /// <summary>
    /// Encrypts a string with AES
    /// </summary>
    /// <param name="plainTextBytes">Bytes to be encrypted</param>
    /// <param name="password">Password to encrypt with</param>
    /// <param name="salt">Salt to encrypt with</param>
    /// <param name="initialVector">Needs to be 16 ASCII characters long</param>
    /// <returns>An encrypted string</returns>
    public static byte[] EncryptToBytes(byte[] plainTextBytes, string password, string salt = null, string initialVector = null)
    {
        int keySize = 256;

        byte[] initialVectorBytes = string.IsNullOrEmpty(initialVector) ? _initVectorBytes : Encoding.UTF8.GetBytes(initialVector);
        byte[] saltValueBytes = string.IsNullOrEmpty(salt) ? _saltBytes : Encoding.UTF8.GetBytes(salt);
        byte[] keyBytes = new Rfc2898DeriveBytes(password, saltValueBytes).GetBytes(keySize / 8);

        using (RijndaelManaged symmetricKey = new RijndaelManaged())
        {
            symmetricKey.Mode = CipherMode.CBC;

            using (ICryptoTransform encryptor = symmetricKey.CreateEncryptor(keyBytes, initialVectorBytes))
            {
                using (MemoryStream memStream = new MemoryStream())
                {
                    using (CryptoStream cryptoStream = new CryptoStream(memStream, encryptor, CryptoStreamMode.Write))
                    {
                        cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length);
                        cryptoStream.FlushFinalBlock();

                        return memStream.ToArray();
                    }
                }
            }
        }
    }

    /// <summary>
    /// Decrypts an AES-encrypted string.
    /// </summary>
    /// <param name="cipherText">Text to be decrypted</param>
    /// <param name="password">Password to decrypt with</param>
    /// <param name="salt">Salt to decrypt with</param>
    /// <param name="initialVector">Needs to be 16 ASCII characters long</param>
    /// <returns>A decrypted string</returns>
    public static string Decrypt(string cipherText, string password, string salt = null, string initialVector = null)
    {
        byte[] cipherTextBytes = Convert.FromBase64String(cipherText.Replace(' ','+'));
        return Decrypt(cipherTextBytes, password, salt, initialVector).TrimEnd('\0');
    }

    /// <summary>
    /// Decrypts an AES-encrypted string.
    /// </summary>
    /// <param name="cipherText">Text to be decrypted</param>
    /// <param name="password">Password to decrypt with</param>
    /// <param name="salt">Salt to decrypt with</param>
    /// <param name="initialVector">Needs to be 16 ASCII characters long</param>
    /// <returns>A decrypted string</returns>
    public static string Decrypt(byte[] cipherTextBytes, string password, string salt = null, string initialVector = null)
    {
        int keySize = 256;

        byte[] initialVectorBytes = string.IsNullOrEmpty(initialVector) ? _initVectorBytes : Encoding.UTF8.GetBytes(initialVector);
        byte[] saltValueBytes = string.IsNullOrEmpty(salt) ? _saltBytes : Encoding.UTF8.GetBytes(salt);
        byte[] keyBytes = new Rfc2898DeriveBytes(password, saltValueBytes).GetBytes(keySize / 8);
        byte[] plainTextBytes = new byte[cipherTextBytes.Length];

        using (RijndaelManaged symmetricKey = new RijndaelManaged())
        {
            symmetricKey.Mode = CipherMode.CBC;

            using (ICryptoTransform decryptor = symmetricKey.CreateDecryptor(keyBytes, initialVectorBytes))
            {
                using (MemoryStream memStream = new MemoryStream(cipherTextBytes))
                {
                    using (CryptoStream cryptoStream = new CryptoStream(memStream, decryptor, CryptoStreamMode.Read))
                    {
                        int byteCount = cryptoStream.Read(plainTextBytes, 0, plainTextBytes.Length);

                        return Encoding.UTF8.GetString(plainTextBytes, 0, byteCount);
                    }
                }
            }
        }
    }
}