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Posted on
2007-12-19 11:37
SummerRain
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* 将BitConverter.ToString的结果转回byte[]
*
* 采用随机的密钥Key和初始化向量IV加密
* 使用随机密码的好处:系统不会产生弱密钥
* 备注:本例与《数据加密标准(DES)的C#实现(2)》本质相同,只是采用BitConverter.ToString
* 输出密文、密钥和初始化向量,而不是采用Base64编码格式
![](/Images/OutliningIndicators/ExpandedBlockStart.gif) /**//*
* 数据加密标准(DES)的C#实现(3)
* 将BitConverter.ToString的结果转回byte[]
*
* 采用随机的密钥Key和初始化向量IV加密
* 使用随机密码的好处:系统不会产生弱密钥
* 备注:本例与《数据加密标准(DES)的C#实现(2)》本质相同,只是采用BitConverter.ToString
* 输出密文、密钥和初始化向量,而不是采用Base64编码格式
*
*
* 夏春涛 Email:xChuntao@163.com
* Blog:http://bluesky521.cnblogs.com
* 运行环境:.net2.0 framework
*/
![](/Images/OutliningIndicators/None.gif)
![](/Images/OutliningIndicators/ExpandedBlockStart.gif) /**//*
* 关于DES加密中的初始化向量IV:
* 对于给定的密钥 k,不使用初始化向量的简单块密码将同一个纯文本输入块加密为
* 同一个密码文本输出块。如果您的纯文本流中有重复块,则您的密码文本流中也会
* 有重复块。如果未经授权的用户知道了您的纯文本块结构的任何信息,他们就可以
* 利用该信息来解密已知的密码文本块,并有可能重新获得您的密钥。为了防止这个
* 问题,前一个块中的信息被混合到下一个块的加密过程中。这样一来,两个相同的
* 纯文本块的输出就变得不一样了。由于此技术使用前一个块加密下一个块,因此需
* 要初始化向量来加密数据的第一个块。
*/
![](/Images/OutliningIndicators/None.gif)
using System;
using System.Collections.Generic;
using System.Text;
using System.Security.Cryptography;
using System.IO;
![](/Images/OutliningIndicators/None.gif)
namespace DES_App3
![](/Images/OutliningIndicators/ExpandedBlockStart.gif) ![](/Images/OutliningIndicators/ContractedBlock.gif) {
class Program
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif) {
static void Main(string[] args)
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif) {
string str_plain_text = "How are you?";
Console.WriteLine("原文:" + str_plain_text);
![](/Images/OutliningIndicators/InBlock.gif)
string KEY_64 = "";
string IV_64 = "";
![](/Images/OutliningIndicators/InBlock.gif)
string str_cypher_text = DES_Encrypt(str_plain_text, out KEY_64, out IV_64);
Console.WriteLine("密文:" + str_cypher_text);
Console.WriteLine("解密:" + DES_Decrypt(str_cypher_text, KEY_64, IV_64));
![](/Images/OutliningIndicators/InBlock.gif)
Console.WriteLine("本次密钥:" + KEY_64);
Console.WriteLine("本次初始化向量:" + IV_64);
Console.WriteLine();
![](/Images/OutliningIndicators/InBlock.gif)
//-------------------------------
![](/Images/OutliningIndicators/InBlock.gif)
str_cypher_text = DES_Encrypt(str_plain_text, out KEY_64, out IV_64, false);
Console.WriteLine("密文:" + str_cypher_text);
![](/Images/OutliningIndicators/InBlock.gif)
Console.WriteLine("解密:" + DES_Decrypt(str_cypher_text, KEY_64, IV_64));
![](/Images/OutliningIndicators/InBlock.gif)
Console.WriteLine("本次密钥:" + KEY_64);
Console.WriteLine("本次初始化向量:" + IV_64);
Console.WriteLine();
}
![](/Images/OutliningIndicators/InBlock.gif)
//将BitConverter.ToString字符串,如"98-ED-0S-9A",还原转换为byte[]
static public byte[] BitStr_ToBytes(string bit_str)
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif) {
string[] arrSplit = bit_str.Split('-');
byte[] byteTemp = new byte[arrSplit.Length];
for (int i = 0; i < byteTemp.Length; i++)
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif) {
byteTemp[i] = byte.Parse(arrSplit[i], System.Globalization.NumberStyles.AllowHexSpecifier);
![](/Images/OutliningIndicators/InBlock.gif)
}
![](/Images/OutliningIndicators/InBlock.gif)
return byteTemp;
}
![](/Images/OutliningIndicators/InBlock.gif)
//将BitConverter.ToString字符串(不含'-'),如"98ED0S9A",还原转换为byte[]
static public byte[] BitStr_ToBytes2(string bit_str)
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif) {
int n = bit_str.Length / 2 - 1;
for (int i = n; i > 0; i--)
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif) {
bit_str = bit_str.Insert(i * 2, "-");
}
![](/Images/OutliningIndicators/InBlock.gif)
return BitStr_ToBytes(bit_str);
}
![](/Images/OutliningIndicators/InBlock.gif)
//----
![](/Images/OutliningIndicators/ContractedSubBlock.gif) DES加密/解密#region DES加密/解密
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif) /**//// <summary>
/// DES加密
/// </summary>
/// <param name="str_plain_text">明文</param>
/// <param name="str_des_key">密钥,8个字符(64bit)</param>
/// <param name="str_des_iv">初始向量,8个字符(64bit)</param>
/// <param name="hasSubSign">输出密文、str_des_key和str_des_iv时,是否保留BitConvert.ToString中的减号</param>
/// <returns>密文</returns>
static public string DES_Encrypt(string str_plain_text, out string str_des_key, out string str_des_iv, bool hasSubSign)
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif) {
string str_cypher_text = "";
![](/Images/OutliningIndicators/InBlock.gif)
DESCryptoServiceProvider cryptoProvider = new DESCryptoServiceProvider();
![](/Images/OutliningIndicators/InBlock.gif)
MemoryStream ms = new MemoryStream();
CryptoStream cst = new CryptoStream(ms, cryptoProvider.CreateEncryptor(), CryptoStreamMode.Write);
![](/Images/OutliningIndicators/InBlock.gif)
StreamWriter sw = new StreamWriter(cst);
sw.Write(str_plain_text);
sw.Flush();
cst.FlushFinalBlock();
sw.Flush();
//-----
str_cypher_text = BitConverter.ToString(ms.GetBuffer(),0,(int)ms.Length);//**
str_des_key = BitConverter.ToString(cryptoProvider.Key);//**
str_des_iv = BitConverter.ToString(cryptoProvider.IV); //**
![](/Images/OutliningIndicators/InBlock.gif)
if (!hasSubSign)
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif) {
str_cypher_text = str_cypher_text.Replace("-", "");
str_des_key = str_des_key.Replace("-","");
str_des_iv = str_des_iv.Replace("-","");
}
![](/Images/OutliningIndicators/InBlock.gif)
return str_cypher_text;
}
![](/Images/OutliningIndicators/InBlock.gif)
static public string DES_Encrypt(string str_plain_text, out string str_des_key, out string str_des_iv)
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif) {
return DES_Encrypt(str_plain_text, out str_des_key, out str_des_iv, true);
}
![](/Images/OutliningIndicators/InBlock.gif)
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif) /**//// <summary>
/// DES解密
/// </summary>
/// <param name="str_cypher_text">密文</param>
/// <param name="str_des_key">密钥,8个字符(64bit)</param>
/// <param name="str_des_iv">初始向量,8个字符(64bit)</param>
/// <returns>明文</returns>
static public string DES_Decrypt(string str_cypher_text, string str_des_key, string str_des_iv)
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif) {
byte[] byKey;
byte[] byIV;
byte[] byEnc;
try
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif) {
if (str_cypher_text.IndexOf('-') > 0 && str_des_key.IndexOf('-') > 0 && str_des_iv.IndexOf('-') > 0)//有"-"号
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif) {
byKey = BitStr_ToBytes(str_des_key);
byIV = BitStr_ToBytes(str_des_iv);
byEnc = BitStr_ToBytes(str_cypher_text);
}
else//无"-"号
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif) {
byKey = BitStr_ToBytes2(str_des_key);
byIV = BitStr_ToBytes2(str_des_iv);
byEnc = BitStr_ToBytes2(str_cypher_text);
}
}
catch
![](/Images/OutliningIndicators/ExpandedSubBlockStart.gif) {
return null;
}
![](/Images/OutliningIndicators/InBlock.gif)
DESCryptoServiceProvider cryptoProvider = new DESCryptoServiceProvider();
MemoryStream ms = new MemoryStream(byEnc);
CryptoStream cst = new CryptoStream(ms, cryptoProvider.CreateDecryptor(byKey, byIV), CryptoStreamMode.Read);
StreamReader sr = new StreamReader(cst);
string str_plain_text = sr.ReadToEnd();
![](/Images/OutliningIndicators/InBlock.gif)
![](/Images/OutliningIndicators/InBlock.gif)
return str_plain_text;
}
#endregion
}
}
![](/Images/OutliningIndicators/None.gif)
源码附件: /Files/bluesky521/DES_Hash_Demo.rar
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