.Net使用DES加密，.Net和java分别解密，并正则匹配替换加密密码为明文

在VS中用WindowsApplication做一个exe程序，用来给数据库密码加密，加密代码如下

 private void generateBtn_Click(object sender, EventArgs e)
        {
            string pwd = pwdtxt.Text;
            if(pwd==null ||pwd.Length==0)
            {
                return;
            }
            string resultPwd = EncryptDES(pwd,"");
            resultPwdTxt.Text = resultPwd;
        }

/**/
        /// <summary>
        /// DES加密字符串
        /// </summary>
        /// <param name="encryptString">待加密的字符串</param>
        /// <param name="encryptKey">加密密钥</param>
        /// <returns>加密成功返回加密后的字符串，失败返回源串</returns>
        private string  EncryptDES(string encryptString, string encryptKey) 
        {
            try
            {
                if (encryptKey.Length < 8)
                {
                    encryptKey += "@#$%^&*!";
                }
                byte[] rgbKey = Encoding.UTF8.GetBytes(encryptKey.Substring (0,8));
                byte[] inputByteArray = Encoding.UTF8.GetBytes(encryptString);
                DESCryptoServiceProvider dCSP = new DESCryptoServiceProvider();
                MemoryStream mStream = new MemoryStream();
                CryptoStream cStream = new CryptoStream(mStream, dCSP.CreateEncryptor(rgbKey, rgbKey), CryptoStreamMode.Write);
                cStream.Write(inputByteArray, 0, inputByteArray.Length);
                cStream.FlushFinalBlock();
                return Convert.ToBase64String(mStream.ToArray());
            }
            catch
            {
                return encryptString;
            }
        }

        /**/
        /// <summary>
        /// DES解密字符串
        /// </summary>
        /// <param name="decryptString">待解密的字符串</param>
        /// <param name="decryptKey">解密密钥,和加密密钥相同</param>
        /// <returns>解密成功返回解密后的字符串，失败返源串</returns>

        private string  DecryptDES(string decryptString, string decryptKey)
        {
            try
            {
                if (decryptKey.Length < 8)
                {
                    decryptKey += "@#$%^&*!";
                }
                byte[] rgbKey = Encoding.UTF8.GetBytes(decryptKey.Substring (0,8));
                byte[] inputByteArray = Convert.FromBase64String(decryptString);
                DESCryptoServiceProvider DCSP = new DESCryptoServiceProvider();
                MemoryStream mStream = new MemoryStream();
                CryptoStream cStream = new CryptoStream(mStream, DCSP.CreateDecryptor(rgbKey, rgbKey), CryptoStreamMode.Write);
                cStream.Write(inputByteArray, 0, inputByteArray.Length);
                cStream.FlushFinalBlock();
                return Encoding.UTF8.GetString(mStream.ToArray());
            }
            catch
            {
                return decryptString;
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {
            string resultPwd = resultPwdTxt.Text;
            string pwd = DecryptDES(resultPwd, "");
            textBox1.Text = pwd;
        }

下面是.net对数据库连接字符串中加密的密码进行密码解密

public static string getdecodePwd(string currentConnectionStr)
        {
            Regex regex = new Regex("(;Password=)(.*)(;)", RegexOptions.IgnoreCase);
            MatchCollection matcheCollection = regex.Matches(currentConnectionStr);
            foreach (Match match in matcheCollection)
            {
                GroupCollection groups = match.Groups;
                if (groups.Count == 4)
                {
                    string enpwd = groups[2].Value;
                    string depwd = DecryptDES(enpwd, "");
                    currentConnectionStr = regex.Replace(currentConnectionStr, ";Password=" + depwd + ";");
                }
            }
            return currentConnectionStr;
        }

        private static string DecryptDES(string decryptString, string decryptKey)
        {
            try
            {
                if (decryptKey.Trim().Length < 8)
                {
                    decryptKey += "@#$%^&*!";
                }
                byte[] rgbKey = Encoding.UTF8.GetBytes(decryptKey.Substring(0, 8));
                byte[] inputByteArray = Convert.FromBase64String(decryptString);
                DESCryptoServiceProvider DCSP = new DESCryptoServiceProvider();
                MemoryStream mStream = new MemoryStream();
                CryptoStream cStream = new CryptoStream(mStream, DCSP.CreateDecryptor(rgbKey, rgbKey), CryptoStreamMode.Write);
                cStream.Write(inputByteArray, 0, inputByteArray.Length);
                cStream.FlushFinalBlock();
                return Encoding.UTF8.GetString(mStream.ToArray());
            }
            catch
            {
                return decryptString;
            }
        }

下面是javat对数据库连接字符串中加密的密码进行密码解密

public static String getdecodePwd(String currentConnectionStr){
        Pattern  regex = Pattern.compile("(;Password=)(.*)(;)",Pattern.CASE_INSENSITIVE); 
        Matcher matcher=regex.matcher(currentConnectionStr); 
        if(matcher.find()&&matcher.groupCount()==3){
            String enpwd = matcher.group(2);
            String depwd = DecryptDES(enpwd, "");
            currentConnectionStr =currentConnectionStr.replaceAll("(;Password=)(.*)(;)",";Password=" + depwd + ";");
        }
        return currentConnectionStr;
    }
    
    private static String DecryptDES(String decryptString,String decryptKey){
        try{
            if(decryptKey.trim().length()<8){
                decryptKey += "@#$%^&*!";
            }
            String key=decryptKey.substring(0, 8);
            BASE64Decoder decoder = new BASE64Decoder();
            byte[] bytesrc = decoder.decodeBuffer(decryptString);
            Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
            DESKeySpec desKeySpec = new DESKeySpec(key.getBytes("UTF-8"));
            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
            SecretKey secretKey = keyFactory.generateSecret(desKeySpec);
            IvParameterSpec iv = new IvParameterSpec(key.getBytes("UTF-8"));
            cipher.init(Cipher.DECRYPT_MODE, secretKey, iv);
            byte[] retByte = cipher.doFinal(bytesrc);
            String result= new String(retByte);
            return result;
        }catch(Exception e){
            e.printStackTrace();
            return "";
        }
    }