加解密总结(附助手类)

Posted fanfan-90

tags:

篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了加解密总结(附助手类)相关的知识,希望对你有一定的参考价值。

对称加密算法:DES、AES、IDEA、RC2、RC4、SKIPJACK……
加解密使用相同密钥,这个是对称加密。对称加密优点是速度快

非对称加密算法:RSA、DSA、DH、ECC、EL GAMAL……
公钥加密数据,然后私钥解密的情况被称为加密解密;
因为公钥加密的数据只有它相对应的私钥可以解开,所以你可以把公钥给人和人,让他加密他想要传送给你的数据,这个数据只有到了有私钥的你这里,才可以解开成有用的数据,其他人就是得到了,也看懂内容
实际应用中,一般都是和对方交换公钥,然后你要发给对方的数据,用他的公钥加密,他得到后用他的私钥解密,他要发给你的数据,用你的公钥加密,你得到后用你的私钥解密,这样最大程度保证了安全性.

缺点速度慢

Hash算法:MD5、SHA1、SHA256……
无论消息有多长,计算出的摘要长度都是固定的,MD5没有SHA算法安全

数字签名:
私钥签名和公钥验证签名;RSA可以用来做签名、验签
如果你用你的私钥对数据进行签名,那这个数据就只有配对的公钥可以解开,有这个私钥的只有你,所以如果配对的公钥解开了数据,就说明这数据是你发的,相反,则不是.这个被称为签名。数字签名的意义就是这些数据与原文数据比对是否修改过。

 

CA证书如何保证网站数据安全:

网站向CA机构申请证书,网站方提供网站信息及公钥给CA机构,CA机构使用自己的私钥对公钥签名,以防篡改。

网站服务器安装CA证书

浏览器发起请求,先请求CA证书,浏览器端保存了CA机构的公钥,对证书验签,验证通过,取出证书中的公钥

使用公钥对http请求信息加密,发起http请求

网站服务器接收到http请求后使用私钥解密。这样就可以防止http请求中的重要信息被拦截者看到,如密码等信息

如果网站没有安装CA证书,也可以在客户端使用RSA加密,公钥保存在浏览器端就可以,我有一篇文章对此有介绍。

 

DES助手类:

 1     /// <summary>
 2     /// 可逆对称加密  密钥长度8
 3     /// </summary>
 4     public class DesEncrypt
 5     {
 6         private static string _key = "fanfanfanfanfan";
 7         private static byte[] _rgbKey = ASCIIEncoding.ASCII.GetBytes(_key.Substring(0, 8));
 8         private static byte[] _rgbIV = ASCIIEncoding.ASCII.GetBytes(_key.Insert(0, "w").Substring(0, 8));
 9 
10         /// <summary>
11         /// DES 加密
12         /// </summary>
13         /// <param name="text">需要加密的值</param>
14         /// <returns>加密后的结果</returns>
15         public static string Encrypt(string text)
16         {
17             DESCryptoServiceProvider dsp = new DESCryptoServiceProvider();
18             using (MemoryStream memStream = new MemoryStream())
19             {
20                 CryptoStream crypStream = new CryptoStream(memStream, dsp.CreateEncryptor(_rgbKey, _rgbIV), CryptoStreamMode.Write);
21                 StreamWriter sWriter = new StreamWriter(crypStream);
22                 sWriter.Write(text);
23                 sWriter.Flush();
24                 crypStream.FlushFinalBlock();
25                 memStream.Flush();
26                 return Convert.ToBase64String(memStream.GetBuffer(), 0, (int)memStream.Length);
27             }
28         }
29 
30         /// <summary>
31         /// DES 解密
32         /// </summary>
33         /// <param name="encryptText"></param>
34         /// <returns>解密后的结果</returns>
35         public static string Decrypt(string encryptText)
36         {
37             DESCryptoServiceProvider dsp = new DESCryptoServiceProvider();
38             byte[] buffer = Convert.FromBase64String(encryptText);
39 
40             using (MemoryStream memStream = new MemoryStream())
41             {
42                 CryptoStream crypStream = new CryptoStream(memStream, dsp.CreateDecryptor(_rgbKey, _rgbIV), CryptoStreamMode.Write);
43                 crypStream.Write(buffer, 0, buffer.Length);
44                 crypStream.FlushFinalBlock();
45                 return ASCIIEncoding.UTF8.GetString(memStream.ToArray());
46             }
47         }
48     }

 

AES助手类:

  1     /// <summary>
  2     /// AES加密解密
  4     /// 密码必须是16位,否则会报错哈
  5     /// </summary>
  6     public class AESCryptoHelper
  7     {
  8         /// <summary>
  9         /// APP默认加密Key
 10         /// </summary>
 11         public static string Default_AESKey = "1111111111111111";//必须是十六位
 12 
 13         /// <summary>
 14         ///  AES 加密
 15         /// </summary>
 16         /// <param name="plainText">明文</param>
 17         /// <param name="key">密码必须是16位,否则会报错哈</param>
 18         /// <returns>密文</returns>
 19         public static string Encrypt(string plainText, string key)
 20         {
 21             string result = null;
 22             if (string.IsNullOrEmpty(plainText))
 23             {
 24                 return result;
 25             }
 26             byte[] plainTextArray = Encoding.UTF8.GetBytes(plainText);
 27             using (RijndaelManaged rijndaelManaged = new RijndaelManaged
 28             {
 29                 Key = Encoding.UTF8.GetBytes(key),
 30                 Mode = CipherMode.ECB,
 31                 Padding = PaddingMode.PKCS7
 32             })
 33             {
 34                 using (ICryptoTransform cryptoTransform = rijndaelManaged.CreateEncryptor())
 35                 {
 36                     byte[] resultArray = cryptoTransform.TransformFinalBlock(plainTextArray, 0, plainTextArray.Length);
 37                     result = Convert.ToBase64String(resultArray, 0, resultArray.Length);
 38                     Array.Clear(resultArray, 0, resultArray.Length);
 39                     resultArray = null;
 40                 }
 41             }
 42             Array.Clear(plainTextArray, 0, plainTextArray.Length);
 43             plainTextArray = null;
 44             return result;
 45         }
 46 
 47         /// <summary>
 48         ///  AES 解密
 49         /// </summary>
 50         /// <param name="encryptText">密文</param>
 51         /// <param name="key">密码必须是16位,否则会报错哈</param>
 52         /// <returns>明文</returns>
 53         public static string Decrypt(string encryptText, string key)
 54         {
 55             string result = null;
 56             if (string.IsNullOrEmpty(encryptText))
 57             {
 58                 return result;
 59             }
 60             byte[] encryptTextArray = Convert.FromBase64String(encryptText);
 61             using (RijndaelManaged rijndaelManaged = new RijndaelManaged
 62             {
 63                 Key = Encoding.UTF8.GetBytes(key),
 64                 Mode = CipherMode.ECB,
 65                 Padding = PaddingMode.PKCS7
 66             })
 67             {
 68                 using (ICryptoTransform cryptoTransform = rijndaelManaged.CreateDecryptor())
 69                 {
 70                     byte[] resultArray = cryptoTransform.TransformFinalBlock(encryptTextArray, 0, encryptTextArray.Length);
 71                     result = Encoding.UTF8.GetString(resultArray);
 72                     Array.Clear(resultArray, 0, resultArray.Length);
 73                     resultArray = null;
 74                 }
 75             }
 76             Array.Clear(encryptTextArray, 0, encryptTextArray.Length);
 77             encryptTextArray = null;
 78             return result;
 79         }
 80 
 81         /// <summary>
 82         /// AES 加密(URL传参数加密)
 83         /// </summary>
 84         /// <param name="plainText">明文</param>
 85         /// <param name="key"></param>
 86         /// <returns>加密之后URL编码</returns>
 87         public static string UrlEncrypt(string plainText, string key)
 88         {
 89             string encryptText = Encrypt(plainText, key);
 90             return HttpUtilityHelper.UrlEncode(encryptText);
 91         }
 92 
 93         /// <summary>
 94         /// AES 解密(URL传参数解密)
 95         /// </summary>
 96         /// <param name="encodeEncryptText">URL编码之后的密文</param>
 97         /// <param name="key"></param>
 98         /// <returns>明文</returns>
 99         public static string UrlDecrypt(string encodeEncryptText, string key)
100         {
101             if (!string.IsNullOrEmpty(encodeEncryptText))
102             {
103                 string encodeText = HttpUtilityHelper.UrlDecode(encodeEncryptText);
104                 return Decrypt(encodeText, key);
105             }
106             return "";
107         }
108     }

 

MD5助手类:

 1     /// <summary>
 2     /// MD5
 3     /// </summary>
 4     public class MD5Encrypt
 5     {
 6         #region MD5
 7         /// <summary>
 8         /// MD5加密,和动网上的16/32位MD5加密结果相同,
 9         /// 使用的UTF8编码
10         /// </summary>
11         /// <param name="source">待加密字串</param>
12         /// <param name="length">16或32值之一,其它则采用.net默认MD5加密算法</param>
13         /// <returns>加密后的字串</returns>
14         public static string Encrypt(string source, int length = 32)//默认参数
15         {
16             if (string.IsNullOrEmpty(source)) return string.Empty;
17             HashAlgorithm provider = CryptoConfig.CreateFromName("MD5") as HashAlgorithm;
18             byte[] bytes = Encoding.UTF8.GetBytes(source);//这里需要区别编码的
19             byte[] hashValue = provider.ComputeHash(bytes);
20             StringBuilder sb = new StringBuilder();
21             switch (length)
22             {
23                 case 16://16位密文是32位密文的9到24位字符
24                     for (int i = 4; i < 12; i++)
25                     {
26                         sb.Append(hashValue[i].ToString("x2"));
27                     }
28                     break;
29                 case 32:
30                     for (int i = 0; i < 16; i++)
31                     {
32                         sb.Append(hashValue[i].ToString("x2"));
33                     }
34                     break;
35                 default:
36                     for (int i = 0; i < hashValue.Length; i++)
37                     {
38                         sb.Append(hashValue[i].ToString("x2"));
39                     }
40                     break;
41             }
42             return sb.ToString();
43         }
44         #endregion MD5
45 
46         #region MD5摘要
47         /// <summary>
48         /// 获取文件的MD5摘要
49         /// </summary>
50         /// <param name="fileName"></param>
51         /// <returns></returns>
52         public static string AbstractFile(string fileName)
53         {
54             using (FileStream file = new FileStream(fileName, FileMode.Open))
55             {
56                 return AbstractFile(file);
57             }
58         }
59 
60         /// <summary>
61         /// 根据stream获取文件摘要
62         /// </summary>
63         /// <param name="stream"></param>
64         /// <returns></returns>
65         public static string AbstractFile(Stream stream)
66         {
67             MD5 md5 = new MD5CryptoServiceProvider();
68             byte[] retVal = md5.ComputeHash(stream);
69 
70             StringBuilder sb = new StringBuilder();
71             for (int i = 0; i < retVal.Length; i++)
72             {
73                 sb.Append(retVal[i].ToString("x2"));
74             }
75             return sb.ToString();
76         }
77         #endregion
78     }

 

RSA助手类:

 1     /// <summary>
 2     /// RSA
 3     /// </summary>
 4     public class RsaEncrypt
 5     {
 6         /// <summary>
 7         /// 生成公钥、私钥
 8         /// </summary>
 9         /// <returns>Encrypt   Decrypt</returns>
10         public static KeyValuePair<string, string> GetKeyPair()
11         {
12             RSACryptoServiceProvider RSA = new RSACryptoServiceProvider();
13             string publicKey = RSA.ToXmlString(false);
14             string privateKey = RSA.ToXmlString(true);
15             return new KeyValuePair<string, string>(publicKey, privateKey);
16         }
17 
18         /// <summary>
19         /// 加密:内容+加密key
20         /// </summary>
21         /// <param name="content"></param>
22         /// <param name="publicKey">加密key</param>
23         /// <returns></returns>
24         public static string Encrypt(string content, string publicKey)
25         {
26             RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
27             rsa.FromXmlString(publicKey);
28             UnicodeEncoding ByteConverter = new UnicodeEncoding();
29             byte[] DataToEncrypt = ByteConverter.GetBytes(content);
30             byte[] resultBytes = rsa.Encrypt(DataToEncrypt, false);
31             return Convert.ToBase64String(resultBytes);
32         }
33 
34         /// <summary>
35         /// 解密  内容+解密key
36         /// </summary>
37         /// <param name="content"></param>
38         /// <param name="privateKey">解密key</param>
39         /// <returns></returns>
40         public static string Decrypt(string content, string privateKey)
41         {
42             byte[] dataToDecrypt = Convert.FromBase64String(content);
43             RSACryptoServiceProvider RSA = new RSACryptoServiceProvider();
44             RSA.FromXmlString(privateKey);
45             byte[] resultBytes = RSA.Decrypt(dataToDecrypt, false);
46             UnicodeEncoding ByteConverter = new UnicodeEncoding();
47             return ByteConverter.GetString(resultBytes);
48         }
49 
50 
51         /// <summary>
52         /// 可以合并在一起的,,每次产生一组新的密钥
53         /// </summary>
54         /// <param name="content"></param>
55         /// <param name="encryptKey">加密key</param>
56         /// <param name="decryptKey">解密key</param>
57         /// <returns>加密后结果</returns>
58         private static string Encrypt(string content, out string publicKey, out string privateKey)
59         {
60             RSACryptoServiceProvider rsaProvider = new RSACryptoServiceProvider();
61             publicKey = rsaProvider.ToXmlString(false);
62             privateKey = rsaProvider.ToXmlString(true);
63 
64             UnicodeEncoding ByteConverter = new UnicodeEncoding();
65             byte[] DataToEncrypt = ByteConverter.GetBytes(content);
66             byte[] resultBytes = rsaProvider.Encrypt(DataToEncrypt, false);
67             return Convert.ToBase64String(resultBytes);
68         }
69     }

 

以上是关于加解密总结(附助手类)的主要内容,如果未能解决你的问题,请参考以下文章

某助手备份手机文件加解密分析

AES加密解密 助手类 CBC加密模式

11.Java 加解密技术系列之 总结

Python3 - RSA双向加解密(详解)

Python3 - RSA双向加解密(详解)

Python3 - RSA双向加解密(详解)