C#(TripleDES)对应Java(3DES)加密工具类

    3DES又称Triple DES，是DES加密算法的一种模式，它使用3条56位的密钥对3DES数据进行三次加密。

    加密过程为：C=Ek3(Dk2(Ek1(P)))

    解密过程为：P=Dk1(EK2(Dk3(C)))

    C#已经对3DES加密进行了封装，可使用System.Security.Cryptography中的TripleDESCryptoServiceProvider类来实现，项目的需求是采用24位KEY、ECB模式来对应java平台的加解密。其中还涉及unix时间戳，MD5散列，base64编码的综合使用。

    开始的时候对HttpWebRequest认识不深，在对base64的编码“+”符号上犯错，POST与GET请求中“+”【%2B】会出现替换的不同，以至于平台解析不成功。以下是测试后的代码：

using System;using System.Text;using System.Security.Cryptography;namespace TestProject{/// <summary>/// 数据加密工具类/// </summary>public sealed class EncryptionUtils{#region DES解密//3DES(DESede>Jave)24位KEYprivate const string ENCRYPT_KEY = "3DES_MD5_Timestamp123456";/// <summary>/// 3DES加密/// base64小细节，当使用get请求时，base64生成字符中有“+”号，/// 注意需要转换“%2B”，否则会被替换成空格。POST不存在/// while (str.IndexOf('+') != -1) {/// str = str.Replace("+","%2B");//  }/// </summary>public static string Encrypt3DES (string fValue){if(string.IsNullOrEmpty(fValue)){return fValue;}try{Encoding encoding = Encoding.GetEncoding("UTF-8");var DES = new TripleDESCryptoServiceProvider();DES.Key = encoding.GetBytes(ENCRYPT_KEY);DES.Mode = CipherMode.ECB;ICryptoTransform DESEncrypt = DES.CreateEncryptor();byte[] Buffer = encoding.GetBytes(fValue);return Convert.ToBase64String(DESEncrypt.TransformFinalBlock(Buffer, 0, Buffer.Length));}catch(Exception ex){Log.Error("Encrypt3DES>>"+ex.Message);return string.Empty;}}/// <summary>/// 3DES解密/// </summary>/// <returns>解密串</returns>/// <param name="a_strString">加密串</param>public static string Decrypt3DES (string a_strString){if(string.IsNullOrEmpty(a_strString)){return a_strString;}try {var DES = new TripleDESCryptoServiceProvider ();DES.Key = ASCIIEncoding.ASCII.GetBytes (ENCRYPT_KEY);DES.Mode = CipherMode.ECB;DES.Padding = System.Security.Cryptography.PaddingMode.PKCS7;ICryptoTransform DESDecrypt = DES.CreateDecryptor ();byte[] Buffer = Convert.FromBase64String (a_strString);return ASCIIEncoding.ASCII.GetString (DESDecrypt.TransformFinalBlock (Buffer, 0, Buffer.Length));} catch (Exception e) {Log.Error("Decrypt3DES>>"+e.Message);return string.Empty;}}#endregion#region 基础方法/// <summary>/// MD5编码/// </summary>public static string MD5(string str){if(string.IsNullOrEmpty(str)){return str;}var md5 = new MD5CryptoServiceProvider();var datas = Encoding.UTF8.GetBytes(str);var hash = md5.ComputeHash(datas);md5.Clear();str = string.Empty;//把MD5所得用16进制小写的字符串形式，让函数返回一个32字节长的可打印字符串。for(int i =0;i<hash.Length;i++){str += hash[i].ToString("X").PadLeft(2,'0');}return str;}/// <summary>/// 并进行base64编码/// </summary>public static string ToBase64String(string str){if(string.IsNullOrEmpty(str)){return string.Empty;}return Convert.ToBase64String(Encoding.UTF8.GetBytes(str));}/// <summary>/// unix时间戳/// </summary>public static string GetTimestamp(){DateTime startTime = TimeZone.CurrentTimeZone.ToLocalTime (new System.DateTime (1970, 1, 1, 0, 0, 0, 0));DateTime nowTime = DateTime.Now;long unixTime = (long)Math.Round ((nowTime - startTime).TotalMilliseconds, MidpointRounding.AwayFromZero);return unixTime.ToString ();}#endregion}public static class Log{public static void Error(string msg){Console.WriteLine ("Error"+msg);}public static void Info(string msg){Console.WriteLine ("Info"+msg);}}}

测试代码：

public static void Main (string[] args){Console.WriteLine ("Hello World!");string line = string.Empty;while ((line = Console.ReadLine ()) != null) {var encrypt = EncryptionUtils.Encrypt3DES (line);var decrypt = EncryptionUtils.Decrypt3DES (encrypt);Log.Info ("输入>>" + line);Log.Info ("密文>>" + encrypt);Log.Info ("明文>>" + decrypt);}}