C#可逆加密-Rijndael算法

CS文件:


using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;

namespace DataCrypto
{
    
/// <summary>
    
/// DataCrypto 的摘要说明
    
/// </summary>

    public class SymmetricMethod
    
{

        
private SymmetricAlgorithm mobjCryptoService;
        
private string Key;
        
/// <summary>
        
/// 对称加密类的构造函数
        
/// </summary>

        public SymmetricMethod()
        
{
            mobjCryptoService 
= new RijndaelManaged();
            Key 
= "lijianfufaicaixiaoke";
        }

        
/// <summary>
        
/// 获得密钥
        
/// </summary>
        
/// <returns>密钥</returns>

        private byte[] GetLegalKey()
        
{
            
string sTemp = Key;
            mobjCryptoService.GenerateKey();
            
byte[] bytTemp = mobjCryptoService.Key;
            
int KeyLength = bytTemp.Length;
            
if (sTemp.Length > KeyLength)
                sTemp 
= sTemp.Substring(0, KeyLength);
            
else if (sTemp.Length < KeyLength)
                sTemp 
= sTemp.PadRight(KeyLength, ' ');
            
return ASCIIEncoding.ASCII.GetBytes(sTemp);
        }

        
/// <summary>
        
/// 获得初始向量IV
        
/// </summary>
        
/// <returns>初试向量IV</returns>

        private byte[] GetLegalIV()
        
{
            
string sTemp = "caoxiaokeailijianfu";
            mobjCryptoService.GenerateIV();
            
byte[] bytTemp = mobjCryptoService.IV;
            
int IVLength = bytTemp.Length;
            
if (sTemp.Length > IVLength)
                sTemp 
= sTemp.Substring(0, IVLength);
            
else if (sTemp.Length < IVLength)
                sTemp 
= sTemp.PadRight(IVLength, ' ');
            
return ASCIIEncoding.ASCII.GetBytes(sTemp);
        }

        
/// <summary>
        
/// 加密方法
        
/// </summary>
        
/// <param name="Source">待加密的串</param>
        
/// <returns>经过加密的串</returns>

        public string Encrypto(string Source)
        
{
            
byte[] bytIn = UTF8Encoding.UTF8.GetBytes(Source);
            MemoryStream ms 
= new MemoryStream();
            mobjCryptoService.Key 
= GetLegalKey();
            mobjCryptoService.IV 
= GetLegalIV();
            ICryptoTransform encrypto 
= mobjCryptoService.CreateEncryptor();
            CryptoStream cs 
= new CryptoStream(ms, encrypto, CryptoStreamMode.Write);
            cs.Write(bytIn, 
0, bytIn.Length);
            cs.FlushFinalBlock();
            ms.Close();
            
byte[] bytOut = ms.ToArray();
            
return Convert.ToBase64String(bytOut);
        }

        
/// <summary>
        
/// 解密方法
        
/// </summary>
        
/// <param name="Source">待解密的串</param>
        
/// <returns>经过解密的串</returns>

        public string Decrypto(string Source)
        
{
            
byte[] bytIn = Convert.FromBase64String(Source);
            MemoryStream ms 
= new MemoryStream(bytIn, 0, bytIn.Length);
            mobjCryptoService.Key 
= GetLegalKey();
            mobjCryptoService.IV 
= GetLegalIV();
            ICryptoTransform encrypto 
= mobjCryptoService.CreateDecryptor();
            CryptoStream cs 
= new CryptoStream(ms, encrypto, CryptoStreamMode.Read);
            StreamReader sr 
= new StreamReader(cs);
            
return sr.ReadToEnd();
        }

    }

}

前台显示:

    protected void Page_Load(object sender, EventArgs e)
    
{
        DataCrypto.SymmetricMethod sm 
= new DataCrypto.SymmetricMethod();
        
string a = sm.Encrypto("asdf").ToString().Trim();
        
string b = sm.Decrypto(a).ToString();
        Response.Write(a
+"<br>"+b);
    }
posted on 2007-05-23 13:19  mbskys  阅读(404)  评论(0编辑  收藏  举报