用C#实现AES加密和解密

AES 是一个新的可以用于保护电子数据的加密算法。明确地说，AES 是一个迭代的、对称密钥分组的密码，它可以使用128、192 和 256 位密钥，并且用 128 位（16字节）分组加密和解密数据。与公共密钥密码使用密钥对不同，对称密钥密码使用相同的密钥加密和解密数据。通过分组密码返回的加密数据 的位数与输入数据相同。迭代加密使用一个循环结构，在该循环中重复置换（permutations ）和替换(substitutions）输入数据。

需要加入引用 using System.Security.Cryptography;

1. /// <summary> 
2.         /// 有密码的AES加密   
3.         /// </summary> 
4.         /// <param name="text">加密字符</param> 
5.         /// <param name="password">加密的密码</param> 
6.         /// <param name="iv">密钥</param> 
7.         /// <returns></returns> 
8.         public static string AESEncrypt(string text, string password, string iv)  
9.         {  
10.             RijndaelManaged rijndaelCipher = new RijndaelManaged();  
11.  
12.             rijndaelCipher.Mode = CipherMode.CBC;  
13.  
14.             rijndaelCipher.Padding = PaddingMode.PKCS7;  
15.  
16.             rijndaelCipher.KeySize = 128;  
17.  
18.             rijndaelCipher.BlockSize = 128;  
19.  
20.             byte[] pwdBytes = System.Text.Encoding.UTF8.GetBytes(password);  
21.  
22.             byte[] keyBytes = new byte[16];  
23.  
24.             int len = pwdBytes.Length;  
25.  
26.             if (len > keyBytes.Length) len = keyBytes.Length;  
27.  
28.             System.Array.Copy(pwdBytes, keyBytes, len);  
29.  
30.             rijndaelCipher.Key = keyBytes;  
31.  
32.  
33.             byte[] ivBytes = System.Text.Encoding.UTF8.GetBytes(iv);  
34.             rijndaelCipher.IV = ivBytes;  
35.  
36.             ICryptoTransform transform = rijndaelCipher.CreateEncryptor();  
37.  
38.             byte[] plainText = Encoding.UTF8.GetBytes(text);  
39.  
40.             byte[] cipherBytes = transform.TransformFinalBlock(plainText, 0, plainText.Length);  
41.  
42.             return Convert.ToBase64String(cipherBytes);  
43.  
44.         }  
45.  
46.         /// <summary> 
47.         /// 随机生成密钥  
48.         /// </summary> 
49.         /// <returns></returns> 
50.         public static string GetIv(int n)  
51.         {  
52.             char[] arrChar = new char[]{  
53.            'a','b','d','c','e','f','g','h','i','j','k','l','m','n','p','r','q','s','t','u','v','w','z','y','x',  
54.            '0','1','2','3','4','5','6','7','8','9',  
55.            'A','B','C','D','E','F','G','H','I','J','K','L','M','N','Q','P','R','T','S','V','U','W','X','Y','Z'  
56.           };  
57.  
58.             StringBuilder num = new StringBuilder();  
59.  
60.             Random rnd = new Random(DateTime.Now.Millisecond);  
61.             for (int i = 0; i < n; i++)  
62.             {  
63.                 num.Append(arrChar[rnd.Next(0, arrChar.Length)].ToString());  
64.  
65.             }  
66.  
67.             return num.ToString();  
68.         }  
69.  
70.         /// <summary> 
71.         /// AES解密  
72.         /// </summary> 
73.         /// <param name="text"></param> 
74.         /// <param name="password"></param> 
75.         /// <param name="iv"></param> 
76.         /// <returns></returns> 
77.         public static string AESDecrypt(string text, string password, string iv)  
78.         {  
79.             RijndaelManaged rijndaelCipher = new RijndaelManaged();  
80.  
81.             rijndaelCipher.Mode = CipherMode.CBC;  
82.  
83.             rijndaelCipher.Padding = PaddingMode.PKCS7;  
84.  
85.             rijndaelCipher.KeySize = 128;  
86.  
87.             rijndaelCipher.BlockSize = 128;  
88.  
89.             byte[] encryptedData = Convert.FromBase64String(text);  
90.  
91.             byte[] pwdBytes = System.Text.Encoding.UTF8.GetBytes(password);  
92.  
93.             byte[] keyBytes = new byte[16];  
94.  
95.             int len = pwdBytes.Length;  
96.  
97.             if (len > keyBytes.Length) len = keyBytes.Length;  
98.  
99.             System.Array.Copy(pwdBytes, keyBytes, len);  
100.  
101.             rijndaelCipher.Key = keyBytes;  
102.  
103.             byte[] ivBytes = System.Text.Encoding.UTF8.GetBytes(iv);  
104.             rijndaelCipher.IV = ivBytes;  
105.  
106.             ICryptoTransform transform = rijndaelCipher.CreateDecryptor();  
107.  
108.             byte[] plainText = transform.TransformFinalBlock(encryptedData, 0, encryptedData.Length);  
109.  
110.             return Encoding.UTF8.GetString(plainText);  
111.  
112.         } 

本文转自linzheng 51CTO博客，原文链接:http://blog.51cto.com/linzheng/1078718