关于C#中使用DES加解密问题

Question

  private static byte[] Keys = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };
        private static string EncryptDES(string encryptString, string encryptKey)
        {
            try
            {                byte[] rgbKey = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 8));
                byte[] rgbIV = Keys;
                byte[] inputByteArray = Encoding.UTF8.GetBytes(encryptString);
                DESCryptoServiceProvider dCSP = new DESCryptoServiceProvider();
                MemoryStream mStream = new MemoryStream();
                CryptoStream cStream = new CryptoStream(mStream, dCSP.CreateEncryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
                cStream.Write(inputByteArray, 0, inputByteArray.Length);
                cStream.FlushFinalBlock();
                return Convert.ToBase64String(mStream.ToArray());
            }
            catch
            {
                return encryptString;
            }
        }        private static string DecryptDES(string decryptString, string decryptKey)
        {
            try
            {
                byte[] rgbKey = Encoding.UTF8.GetBytes(decryptKey.Substring(0, 8));
                byte[] rgbIV = Keys;
                byte[] inputByteArray = Convert.FromBase64String(decryptString);
                DESCryptoServiceProvider DCSP = new DESCryptoServiceProvider();
                MemoryStream mStream = new MemoryStream();
                CryptoStream cStream = new CryptoStream(mStream, DCSP.CreateDecryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
                cStream.Write(inputByteArray, 0, inputByteArray.Length);
                cStream.FlushFinalBlock();                return Encoding.UTF8.GetString(mStream.ToArray());
            }
            catch(Exception ex)
            {
                return decryptString;
            }
        }
以上是我使用的对于字符串加解密的方法，以前使用都是OK的，但是现在使用加密时在 CryptoStream cStream = new CryptoStream(mStream, dCSP.CreateEncryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
就有错误了，但是还可以继续，可以返回加密后的字符串，但是等到解密时，系统会Catch到Exception，也是在   CryptoStream cStream = new CryptoStream(mStream, DCSP.CreateDecryptor(rgbKey, rgbIV), CryptoStreamMode.Write);时就有错误了，错误信息是
+ Length “cStream.Length”引发了“System.NotSupportedException”类型的异常 long {System.NotSupportedException}
，，，+ Position “cStream.Position”引发了“System.NotSupportedException”类型的异常 long {System.NotSupportedException}然后要运行到cStream.FlushFinalBlock();才会跳到异常捕获代码。异常信息为“不正确的数据”，ex.StackTrace为：
   在 System.Security.Cryptography.CryptographicException.ThrowCryptogaphicException(Int32 hr)
   在 System.Security.Cryptography.Utils._DecryptData(SafeKeyHandle hKey, Byte[] data, Int32 ib, Int32 cb, Byte[]& outputBuffer, Int32 outputOffset, PaddingMode PaddingMode, Boolean fDone)
   在 System.Security.Cryptography.CryptoAPITransform.TransformFinalBlock(Byte[] inputBuffer, Int32 inputOffset, Int32 inputCount)
   在 System.Security.Cryptography.CryptoStream.FlushFinalBlock()
   在 KM.Web.Utility.CryptBase.DecryptDES(String decryptString, String decryptKey) 位置 d:\KM3.0\03_Code\01_SourceCode\KM3.0\KM3.0\KMWeb\App_Code\CryptBase.cs:行号 57请各位牛人帮忙解决，谢谢！

Answer 1

记得C#里边的DES加密只能用ASC,用别的报错.

Answer 2

用C#实现DES加密解密
using System;
using System.Security.Cryptography;
using System.Text;
using System.IO;namespace Common
...{
    /**//// <summary>
    /// DESEncrypt加密解密算法。
    /// </summary>
    public sealed class DESEncrypt
    ...{
        private DESEncrypt()
        ...{
            //
            // TODO: 在此处添加构造函数逻辑
            //
        }        private static string key = "zhoufoxcn";        /**//// <summary>
        /// 对称加密解密的密钥
        /// </summary>
        public static string Key
        ...{
            get
            ...{
                return key;
            }
            set
            ...{
                key = value;
            }
        }        /**//// <summary>
        /// DES加密
        /// </summary>
        /// <param name="encryptString"></param>
        /// <returns></returns>
        public static string DesEncrypt(string encryptString)
        ...{
            byte[] keyBytes = Encoding.UTF8.GetBytes(key.Substring(0, 8));
            byte[] keyIV = keyBytes;
            byte[] inputByteArray = Encoding.UTF8.GetBytes(encryptString);
            DESCryptoServiceProvider provider = new DESCryptoServiceProvider();
            MemoryStream mStream = new MemoryStream();
            CryptoStream cStream = new CryptoStream(mStream, provider.CreateEncryptor(keyBytes, keyIV), CryptoStreamMode.Write);
            cStream.Write(inputByteArray, 0, inputByteArray.Length);
            cStream.FlushFinalBlock();
            return Convert.ToBase64String(mStream.ToArray());
        }        /**//// <summary>
        /// DES解密
        /// </summary>
        /// <param name="decryptString"></param>
        /// <returns></returns>
        public static string DesDecrypt(string decryptString)
        ...{
            byte[] keyBytes = Encoding.UTF8.GetBytes(key.Substring(0, 8));
            byte[] keyIV = keyBytes;
            byte[] inputByteArray = Convert.FromBase64String(decryptString);
            DESCryptoServiceProvider provider = new DESCryptoServiceProvider();
            MemoryStream mStream = new MemoryStream();
            CryptoStream cStream = new CryptoStream(mStream, provider.CreateDecryptor(keyBytes, keyIV), CryptoStreamMode.Write);
            cStream.Write(inputByteArray, 0, inputByteArray.Length);
            cStream.FlushFinalBlock();
            return Encoding.UTF8.GetString(mStream.ToArray());
        }
    }
}

Answer 3

加密与解密只要有加密就够用了
你将得到的字符串进行加密然后比较两串加密的字符串就可以。
在我的空间里有MD5，DES等加解密的案例

Answer 4

我测试了一下你的代码.很正常
public class Program
    {
        private static byte[] Keys = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };         static void Main(string[] args)
        {
            string key = "123456789";            string str = "cc";            string str2 = EncryptDES(str, key);
            Console.WriteLine(str2);            Console.WriteLine(DecryptDES(str2, key));            Console.ReadKey();
        }        private static string EncryptDES(string encryptString, string encryptKey)
        {
            try
            {                byte[] rgbKey = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 8));
                byte[] rgbIV = Keys;
                byte[] inputByteArray = Encoding.UTF8.GetBytes(encryptString);
                DESCryptoServiceProvider dCSP = new DESCryptoServiceProvider();
                MemoryStream mStream = new MemoryStream();
                CryptoStream cStream = new CryptoStream(mStream, dCSP.CreateEncryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
                cStream.Write(inputByteArray, 0, inputByteArray.Length);
                cStream.FlushFinalBlock();
                return Convert.ToBase64String(mStream.ToArray());
            }
            catch
            {
                return encryptString;
            }
        }        private static string DecryptDES(string decryptString, string decryptKey)
        {
            try
            {
                byte[] rgbKey = Encoding.UTF8.GetBytes(decryptKey.Substring(0, 8));
                byte[] rgbIV = Keys;
                byte[] inputByteArray = Convert.FromBase64String(decryptString);
                DESCryptoServiceProvider DCSP = new DESCryptoServiceProvider();
                MemoryStream mStream = new MemoryStream();
                CryptoStream cStream = new CryptoStream(mStream, DCSP.CreateDecryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
                cStream.Write(inputByteArray, 0, inputByteArray.Length);
                cStream.FlushFinalBlock(); return Encoding.UTF8.GetString(mStream.ToArray());
            }
            catch (Exception ex)
            {
                return decryptString;
            }
        } 
    }   

Answer 5

不过你的代码看着就怪.那两个方法都有一个Key了(第二个参数)
你还要一个private的Keys干啥?代码我也没仔细看,感觉很奇怪.不过能测试通过发两个方法,参考一下.我一直在用#region TripleDES加/解密
/// <summary>
/// TripleDES解密
/// </summary>
public static string TripleDESDecrypt(string encryptedString,string key)
{
if(encryptedString.Equals(string.Empty))
{
return encryptedString;
}
TripleDESCryptoServiceProvider tdes=new TripleDESCryptoServiceProvider();
 
//将秘钥编码成为二进制数组
PasswordDeriveBytes derive = new PasswordDeriveBytes(key,null);
byte[] tdesIV=new byte[8];
byte[] btaKey=derive.CryptDeriveKey("TripleDES","SHA1",0,tdesIV); //从字符串转换为字节组
byte[] btaCode=System.Convert.FromBase64String(encryptedString); tdes.Mode = CipherMode.ECB;
MemoryStream ms=new MemoryStream(btaCode); CryptoStream encStream = new CryptoStream(ms,tdes.CreateDecryptor(btaKey,tdesIV),CryptoStreamMode.Read);
StreamReader sr=new StreamReader(encStream,System.Text.Encoding.Unicode);
string strtmp=sr.ReadToEnd();
sr.Close();
encStream.Close(); return strtmp;
} /// <summary>
/// TripleDES加密
/// </summary>
public static string TripleDESEcrypt(string plainString,string key)
{
if(plainString.Equals(string.Empty))
{
return plainString;
} TripleDESCryptoServiceProvider tdes=new TripleDESCryptoServiceProvider();

//将秘钥编码成为二进制数组
PasswordDeriveBytes derive = new PasswordDeriveBytes(key,null);
byte[] tdesIV=new byte[8];
byte[] btaKey=derive.CryptDeriveKey("TripleDES","SHA1",0,tdesIV); //从字符串转换为字节组
byte[] btaCode=Encoding.Unicode.GetBytes(plainString); tdes.Mode = CipherMode.ECB;
MemoryStream ms=new MemoryStream();

CryptoStream encStream = new CryptoStream(ms,tdes.CreateEncryptor(btaKey,tdesIV),CryptoStreamMode.Write);
encStream.Write(btaCode, 0, btaCode.Length);
encStream.FlushFinalBlock();
encStream.Close(); //再转换为一个字符串
return System.Convert.ToBase64String(ms.ToArray());
}
#endregion

Answer 6

对了，我以前开发环境是英文版的visual studio2005，现在使用的时中文版的，不知这有影响吗？应该没有吧？？

Answer 7

我要加密的时URL后面的字符串，例如 http:wwww.dddd.com/a.aspx?mod,406中的 “mod,406”进行加密，以前开发工具时英文版时是没有问题的，但现在visual studio2005时中文版的，就有问题了。

Answer 8

我试了一下mod,406用你的代码没问题.我的是英文的.我这没有中文的,没办法测.

Answer 9

http://blog.csdn.net/PPLUNCLE/archive/2006/06/21/817828.aspx你看一下这篇文章下面的评论.

Answer 10

byte[] rgbKey = Encoding.ASCII.GetBytes(encryptKey.Substring(0, 8));
都改成ASC的.

Answer 11

我用英文版的应该也没有问题，但是为什么中文版的出现这个错误呢？根据搜索的信息，好像是设置BLOCKSIZE 和FEEDBACKSIZE  就行了，请问怎么设置？

Answer 12

用过加解密：#region   对数据进行加密
        /// <summary>
        /// 对数据进行加密
        /// </summary>
        /// <param name="encryptstring">需要加密的数据</param>
        /// <returns></returns>
        public string DESEncrypt(string encryptstring)
        {
            string strRtn;
            try
            {
                DESCryptoServiceProvider desc = new DESCryptoServiceProvider();//des进行加密
                byte[] key = System.Text.Encoding.Unicode.GetBytes(encryptkey);
                byte[] data = System.Text.Encoding.Unicode.GetBytes(encryptstring);
                MemoryStream ms = new MemoryStream();//存储加密后的数据
                CryptoStream cs = new CryptoStream(ms, desc.CreateEncryptor(key, key), CryptoStreamMode.Write);
                cs.Write(data, 0, data.Length);//进行加密
                cs.FlushFinalBlock();
                strRtn = Convert.ToBase64String(ms.ToArray());
                return strRtn;
            }            catch (Exception ex)
            {
                MessageBox.Show("错误：" + ex.Message, "错误消息提示框", MessageBoxButtons.OKCancel, MessageBoxIcon.Error);
                return null;
            }
        }
        #endregion        #region   对数据进行解密
        /// <summary>
        /// 对数据进行解密
        /// </summary>
        /// <param name="decryptstring">需要解密的数据</param>
        /// <returns></returns>
        public string DESDecrypt(string decryptstring)
        {
string strRtn;
            try
            {
                DESCryptoServiceProvider desc = new DESCryptoServiceProvider();
                byte[] key = System.Text.Encoding.Unicode.GetBytes(encryptkey);
                byte[] data = Convert.FromBase64String(decryptstring);
                MemoryStream ms = new MemoryStream();//存储解密后的数据
                CryptoStream cs = new CryptoStream(ms, desc.CreateDecryptor(key, key), CryptoStreamMode.Write);
                cs.Write(data, 0, data.Length);//解密数据
                cs.FlushFinalBlock();
                strRtn = System.Text.Encoding.Unicode.GetString(ms.ToArray());
                return strRtn;
            }
            catch (Exception ex)
            {
                MessageBox.Show("错误：" + ex.Message, "错误消息提示框", MessageBoxButtons.OKCancel, MessageBoxIcon.Error);
                return null;
            }
        }
        #endregion