C# 实现RSA AES加密解密

深藏阁楼爱情的钟 2023-05-30 06:08 16阅读 0赞

### RAS： ###

C\#  System.Security.Cryptography 提供了base64和xmlstring两种方式，我更喜欢base64的

> RSA是非对称加密，经典的对称加密就是DES，AES等，不过这两种算法的缺点是加解密双方都必须知道密钥，安全性不高
> 
> RSA则可以解决这个问题，生成公钥和私钥，公钥可以公开给其他人，私钥自己保管，别人用公钥加密后，自己用私钥解密。

RSA代码如下：

using System;
    using System.Collections.Generic;
    using System.Security.Cryptography;
    using System.Text;
    using System.Windows;
    
    namespace RSA
    {
        public partial class MainWindow : Window
        {
            public MainWindow()
            {
                InitializeComponent();
                RSAUtil rsaInstance = new RSAUtil();
                var dictK = rsaInstance.GetKey();
                string strText = "aaabbbcc";
                Console.WriteLine("要加密的字符串是：{0}", strText);
                string str1 = rsaInstance.Encrypt(strText, dictK["PublicKey"]);
                Console.WriteLine("加密后的字符串：{0}", str1);
                string str2 = rsaInstance.Decrypt(str1, dictK["PrivateKey"]);
                Console.WriteLine("解密后的字符串：{0}", str2);
            }
        }
    
        public class RSAUtil
        {
            /// <summary>
            /// 使用公钥加密
            /// </summary>
            /// <returns></returns>
            public string Encrypt(string strText, string strPublicKey)
            {
                RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
                rsa.ImportCspBlob(Convert.FromBase64String(strPublicKey));
                byte[] byteText = Encoding.UTF8.GetBytes(strText);
                byte[] byteEntry = rsa.Encrypt(byteText, false);
                return Convert.ToBase64String(byteEntry);
            }
    
            /// <summary>
            /// 私钥解密
            /// </summary>
            /// <param name="strEntryText"></param>
            /// <param name="strPrivateKey"></param>
            /// <returns></returns>
            public string Decrypt(string strEntryText, string strPrivateKey)
            {
                RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
                rsa.ImportCspBlob(Convert.FromBase64String(strPrivateKey));
                byte[] byteEntry = Convert.FromBase64String(strEntryText);
                byte[] byteText = rsa.Decrypt(byteEntry, false);
                return Encoding.UTF8.GetString(byteText);
            }
    
            /// <summary>
            /// 获取公钥和私钥
            /// </summary>
            /// <returns></returns>
            public Dictionary<string, string> GetKey()
            {
                Dictionary<string, string> dictKey = new Dictionary<string, string>();
                RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
                string public_Key = Convert.ToBase64String(rsa.ExportCspBlob(false));
                string private_Key = Convert.ToBase64String(rsa.ExportCspBlob(true));
                dictKey.Add("PublicKey", public_Key);
                dictKey.Add("PrivateKey", private_Key);
                return dictKey;
            }
        }
    }

### AES代码如下： ###

using System;
    using System.IO;
    using System.Security.Cryptography;
    using System.Text;
    
    namespace AEStest
    {
        class Program
        {
            //为什么要用base64,因为得到的密文是byte[]，所以默认用base64转成str方便查看
            static void Main(string[] args)
            {
                string password = "abcAE#$M&*987";
                Console.WriteLine($"原始密码为:{password} ");
                string key = "1234567890qwerty";//16字节，128位
    
                var EncryptStr = Encrypt(key, password);
                Console.WriteLine($"使用密钥:{key} 为原密码：{password} 加密");
                Console.WriteLine($"得到密文：{EncryptStr}");
    
                Console.WriteLine($"使用密钥:{key} 为密文：{EncryptStr} 解密");
                var realPwd = Decrypt(key, EncryptStr);
                Console.WriteLine($"得到原密码：{realPwd}");
            }
    
            // AES 加密的初始化向量,加密解密需设置相同的值。默认值我们设置成 16 个 0
            public static byte[] AES_IV = Encoding.UTF8.GetBytes("0000000000000000");
    
            // AES的key支持128位，最大支持256位。256位需要32个字节。
            // 所以这里使用密钥的前 32 字节作为 key ,不足32补 0。
            public static byte[] GetKey(string pwd)
            {
                while (pwd.Length < 32)
                {
                    pwd += '0';
                }
                pwd = pwd.Substring(0, 32);
                return Encoding.UTF8.GetBytes(pwd);
            }
    
    
    
    
            /// <summary>
            ///  加密
            /// </summary>
            /// <param name="key">密钥</param>
            /// <param name="password">要被加密的原始密码</param>
            /// <returns>密文base64</returns>
            public static string Encrypt(string key, string password)
            {
                using (AesCryptoServiceProvider aesAlg = new AesCryptoServiceProvider())
                {
                    aesAlg.Key = GetKey(key);
                    aesAlg.IV = AES_IV;
                    ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);
                    using (MemoryStream msEncrypt = new MemoryStream())
                    {
                        using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
                        {
                            using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
                            {
                                swEncrypt.Write(password);
                            }
                            byte[] bytes = msEncrypt.ToArray();
                            return Convert.ToBase64String(bytes);
                        }
                    }
                }
            }
    
            /// <summary>
            /// 解密
            /// </summary>
            /// <param name="key">密钥</param>
            /// <param name="EncryptStr">密文</param>
            /// <returns>明文-原密码</returns>
            public static string Decrypt(string key, string EncryptStr)
            {
                byte[] inputBytes = Convert.FromBase64String(EncryptStr);
                using (AesCryptoServiceProvider aesAlg = new AesCryptoServiceProvider())
                {
                    aesAlg.Key = GetKey(key);
                    aesAlg.IV = AES_IV;
    
                    ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);
                    using (MemoryStream msEncrypt = new MemoryStream(inputBytes))
                    {
                        using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, decryptor, CryptoStreamMode.Read))
                        {
                            using (StreamReader srEncrypt = new StreamReader(csEncrypt))
                            {
                                return srEncrypt.ReadToEnd();
                            }
                        }
                    }
                }
            }
        }
    }

AES加解密，不同语言之间，需要对上AES的模式，密钥，向量， 编码格式