net core 配置文件加密（RSA加密）

前言

在配置文件中，数据库连接字符串，缓存链接字符串等敏感信息，需要配置成加密形式。今天记录一下工作经验

我使用的是RSA加密
先安装依赖包

首先生成公钥私钥

公钥与私钥是匹配的，公钥加密过后使用对应的私钥进行解密

        /// <summary>
        /// 生成PEM格式的公钥和密钥
        /// </summary>
        /// <param name="strength">长度</param>
        /// <returns>Item1:公钥；Item2:私钥；</returns>
        public static (string, string) CreateKeyPair(int strength = 1024)
        {
            RsaKeyPairGenerator r = new RsaKeyPairGenerator();
            r.Init(new KeyGenerationParameters(new SecureRandom(), strength));
            AsymmetricCipherKeyPair keys = r.GenerateKeyPair();
            TextWriter privateTextWriter = new StringWriter();
            PemWriter privatePemWriter = new PemWriter(privateTextWriter);
            privatePemWriter.WriteObject(keys.Private);
            privatePemWriter.Writer.Flush();
            TextWriter publicTextWriter = new StringWriter();
            PemWriter publicPemWriter = new PemWriter(publicTextWriter);
            publicPemWriter.WriteObject(keys.Public);
            publicPemWriter.Writer.Flush();
            return (publicTextWriter.ToString(), privateTextWriter.ToString());
        }

RSA加密算法

                /// <summary>
                /// RSA加密
                /// </summary>
                /// <param name="publicKey">公钥</param>
                /// <param name="decryptstring">待加密的字符串(Base64)</param>
                /// <returns>加密后的字符串</returns>
               public static string Crypt(string publicKey, string decryptstring)
               {
                    decryptstring = Convert.ToBase64String(System.Text.Encoding.Default.GetBytes(decryptstring));
                  using (TextReader reader = new StringReader(publicKey))
                 {
                     dynamic key = new PemReader(reader).ReadObject();
                     var rsaDecrypt = new Pkcs1Encoding(new RsaEngine());
                     if (key is AsymmetricKeyParameter)
                     {
                        key = (AsymmetricKeyParameter)key;
                     }
                     else if (key is AsymmetricCipherKeyPair)
                     {
                        key = ((AsymmetricCipherKeyPair)key).Private;
                     }
                     rsaDecrypt.Init(true, key); //这里加密是true；解密是false

                     byte[] entData = Convert.FromBase64String(decryptstring);
                     entData = rsaDecrypt.ProcessBlock(entData, 0, entData.Length);
                     return Convert.ToBase64String(entData);
                 }
              }

RSA解密算法

        /// <summary>
        /// RSA解密,解密失败返回原字符串
        /// </summary>
        /// <param name="privateKey">私钥</param>
        /// <param name="decryptstring">待解密的字符串(Base64)</param>
        /// <returns>解密后的字符串</returns>
        public static string Decrypt(string privateKey, string decryptstring)
        {
            try
            {
                using (TextReader reader = new StringReader(privateKey))
                {
                    dynamic key = new PemReader(reader).ReadObject();
                    var rsaDecrypt = new Pkcs1Encoding(new RsaEngine());
                    if (key is AsymmetricKeyParameter)
                    {
                        key = (AsymmetricKeyParameter)key;
                    }
                    else if (key is AsymmetricCipherKeyPair)
                    {
                        key = ((AsymmetricCipherKeyPair)key).Private;
                    }
                    rsaDecrypt.Init(false, key); //这里加密是true；解密是false

                    byte[] entData = Convert.FromBase64String(decryptstring);
                    entData = rsaDecrypt.ProcessBlock(entData, 0, entData.Length);
                    return Encoding.UTF8.GetString(entData);
                } 
            }
            catch (Exception e)
            {
                return decryptstring;
            }
        }