数据加密标准(DES)的C#实现(3)--（将BitConverter.ToString的结果转回byte[]）
简介：
/**//* * 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.
/**/
/*
* 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
*/
/**/
/*
* 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。
*/
using
System;
using
System.Collections.Generic;
using
System.Text;
using
System.Security.Cryptography;
using
System.IO;
namespace
DES_App3
{
class Program
{
static void Main(string[] args)
{
string str_plain_text = "How are you?";
Console.WriteLine("原文：" + str_plain_text);
string KEY_64 = "";
string IV_64 = "";
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));
Console.WriteLine("本次密钥：" + KEY_64);
Console.WriteLine("本次初始化向量：" + IV_64);
Console.WriteLine();
//-------------------------------
str_cypher_text = DES_Encrypt(str_plain_text, out KEY_64, out IV_64, false);
Console.WriteLine("密文：" + str_cypher_text);
Console.WriteLine("解密：" + DES_Decrypt(str_cypher_text, KEY_64, IV_64));
Console.WriteLine("本次密钥：" + KEY_64);
Console.WriteLine("本次初始化向量：" + IV_64);
Console.WriteLine();
}
//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)
{
string[] arrSplit = bit_str.Split('-');
byte[] byteTemp = new byte[arrSplit.Length];
for (int i = 0; i < byteTemp.Length; i++)
{
byteTemp[i] = byte.Parse(arrSplit[i], System.Globalization.NumberStyles.AllowHexSpecifier);
}
return byteTemp;
}
//将BitConverter.ToString字符串(不含'-'),如"98ED0S9A"，还原转换为byte[]
static public byte[] BitStr_ToBytes2(string bit_str)
{
int n = bit_str.Length / 2 - 1;
for (int i = n; i > 0; i--)
{
bit_str = bit_str.Insert(i * 2, "-");
}
return BitStr_ToBytes(bit_str);
}
//----
DES加密/解密#region DES加密/解密
/**//// <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)
{
string str_cypher_text = "";
DESCryptoServiceProvider cryptoProvider = new DESCryptoServiceProvider();
MemoryStream ms = new MemoryStream();
CryptoStream cst = new CryptoStream(ms, cryptoProvider.CreateEncryptor(), CryptoStreamMode.Write);
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); //**
if (!hasSubSign)
{
str_cypher_text = str_cypher_text.Replace("-", "");
str_des_key = str_des_key.Replace("-","");
str_des_iv = str_des_iv.Replace("-","");
}
return str_cypher_text;
}
static public string DES_Encrypt(string str_plain_text, out string str_des_key, out string str_des_iv)
{
return DES_Encrypt(str_plain_text, out str_des_key, out str_des_iv, true);
}
/**//// <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)
{
byte[] byKey;
byte[] byIV;
byte[] byEnc;
try
{
if (str_cypher_text.IndexOf('-') > 0 && str_des_key.IndexOf('-') > 0 && str_des_iv.IndexOf('-') > 0)//有"-"号
{
byKey = BitStr_ToBytes(str_des_key);
byIV = BitStr_ToBytes(str_des_iv);
byEnc = BitStr_ToBytes(str_cypher_text);
}
else//无"-"号
{
byKey = BitStr_ToBytes2(str_des_key);
byIV = BitStr_ToBytes2(str_des_iv);
byEnc = BitStr_ToBytes2(str_cypher_text);
}
}
catch
{
return null;
}
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();
return str_plain_text;
}
#endregion
}
}
源码附件：
/Files/bluesky521/DES_Hash_Demo.rar
