RSA非对称加密算法在C#中的实现（.NET/C#实现RSA非对称加密算法）

using Cari.Safety.SSO.Interface;
using System;
using Org.BouncyCastle.Asn1;
using Org.BouncyCastle.Asn1.Pkcs;
using Org.BouncyCastle.Asn1.X509;
using Org.BouncyCastle.Crypto;
using Org.BouncyCastle.Crypto.Encodings;
using Org.BouncyCastle.Crypto.Engines;
using Org.BouncyCastle.Crypto.Generators;
using Org.BouncyCastle.Crypto.Parameters;
using Org.BouncyCastle.Pkcs;
using Org.BouncyCastle.Security;
using Org.BouncyCastle.X509;
using System.Text;
using System.ComponentModel.Composition;

namespace Cari.Safety.SSO.Tool
{
    /// 

    /// Summary: RSA非对称加密算法实现
    /// API详情请参考: http://www.bouncycastle.org/csharp/
    /// 密钥默认长度为1024（应该够用吧），可以解密的源字符串最大长度为：密钥长度/8-11，这里就是1024/8-11=117
    /// Author: Lee Liu
    /// Date: 20181031
    /// 
    [Export("RSA",typeof(IRSAHelper))]
    public class RSA : IRSAHelper
    {
        //设定编码方式为UTF-8
        private static Encoding Encoding_UTF8 = Encoding.UTF8;

        //全局变量: RSA公私密钥对
        private RSAKEY keyPair;

        //RSA引用，这里用作单例模式使用。
        private static RSA rsa;

        #region 私有化无参构造方法
        private RSA()
        {
            keyPair = GetKey();
        }
        #endregion

        #region 单例模式，获取RSA类的实例
        /// 

        /// 单例模式，获取RSA类的实例
        /// 
        /// 
        public static RSA GetRSAInstance()
        {
            if (rsa != null)
            {
                return rsa;
            }
            else
            {
                return new RSA();
            }
        }
        #endregion

        #region 实现IRSAHelper接口
        public string DecryptViaPrivateKey(string data, string privateKey)
        {
            return DecryptByPrivateKey(data, privateKey);
        }

        public string DecryptViaPublicKey(string data, string publicKey)
        {
            return DecryptByPublicKey(data, publicKey);
        }

        public string EncryptViaPrivateKey(string data, string privateKey)
        {
            return EncryptByPrivateKey(data, privateKey);
        }

        public string EncryptViaPublicKey(string data, string publicKey)
        {
            return EncryptByPublicKey(data, publicKey);
        }

        public string GetPrivateKey()
        {
            return keyPair.PrivateKey;
        }

        public string GetPublicKey()
        {
            return keyPair.PublicKey;
        }

        public void SetPrivateKey(string privateKey)
        {
            keyPair.PrivateKey = privateKey;
        }

        public void SetPublicKey(string publicKey)
        {
            keyPair.PublicKey = publicKey;
        }
        #endregion

        #region Key Pair结构体
        /// 

        /// KEY 结构体
        /// 
        public struct RSAKEY
        {
            /// 

            /// 公钥
            /// 
            public string PublicKey
            {
                get;
                set;
            }
            /// 

            /// 私钥
            /// 
            public string PrivateKey
            {
                get;
                set;
            }
        }
        #endregion

        #region 获取公私钥
        private RSAKEY GetKey()
        {
            //RSA密钥对的构造器  
            RsaKeyPairGenerator keyGenerator = new RsaKeyPairGenerator();

            //RSA密钥构造器的参数  
            RsaKeyGenerationParameters param = new RsaKeyGenerationParameters(
                Org.BouncyCastle.Math.BigInteger.ValueOf(3),
                new Org.BouncyCastle.Security.SecureRandom(),
                1024,   //密钥长度  
                25);
            //用参数初始化密钥构造器  
            keyGenerator.Init(param);
            //产生密钥对  
            AsymmetricCipherKeyPair keyPair = keyGenerator.GenerateKeyPair();
            //获取公钥和密钥  
            AsymmetricKeyParameter publicKey = keyPair.Public;
            AsymmetricKeyParameter privateKey = keyPair.Private;

            SubjectPublicKeyInfo subjectPublicKeyInfo = SubjectPublicKeyInfoFactory.CreateSubjectPublicKeyInfo(publicKey);
            PrivateKeyInfo privateKeyInfo = PrivateKeyInfoFactory.CreatePrivateKeyInfo(privateKey);

            Asn1Object asn1ObjectPublic = subjectPublicKeyInfo.ToAsn1Object();

            byte[] publicInfoByte = asn1ObjectPublic.GetEncoded("UTF-8");
            Asn1Object asn1ObjectPrivate = privateKeyInfo.ToAsn1Object();
            byte[] privateInfoByte = asn1ObjectPrivate.GetEncoded("UTF-8");

            RSAKEY item = new RSAKEY()
            {
                PublicKey = Convert.ToBase64String(publicInfoByte),
                PrivateKey = Convert.ToBase64String(privateInfoByte)
            };
            return item;
        }
        #endregion

        #region 获取公私钥参数
        /// 

        /// 获取公钥参数
        /// 
        /// 公钥
        /// 
        private AsymmetricKeyParameter GetPublicKeyParameter(string keyBase64)
        {
            keyBase64 = keyBase64.Replace("r", "").Replace("n", "").Replace(" ", "");
            byte[] publicInfoByte = Convert.FromBase64String(keyBase64);
            Asn1Object pubKeyObj = Asn1Object.FromByteArray(publicInfoByte);//这里也可以从流中读取，从本地导入   
            AsymmetricKeyParameter pubKey = PublicKeyFactory.CreateKey(publicInfoByte);
            return pubKey;
        }

        /// 

        /// 获取私钥参数
        /// 
        /// 私钥
        /// 
        private AsymmetricKeyParameter GetPrivateKeyParameter(string keyBase64)
        {
            keyBase64 = keyBase64.Replace("r", "").Replace("n", "").Replace(" ", "");
            byte[] privateInfoByte = Convert.FromBase64String(keyBase64);
            // Asn1Object priKeyObj = Asn1Object.FromByteArray(privateInfoByte);//这里也可以从流中读取，从本地导入   
            // PrivateKeyInfo privateKeyInfo = PrivateKeyInfoFactory.CreatePrivateKeyInfo(privateKey);
            AsymmetricKeyParameter priKey = PrivateKeyFactory.CreateKey(privateInfoByte);
            return priKey;
        }
        #endregion

        #region 使用私钥加密内容
        /// 

        /// 私钥加密
        /// 
        /// 加密内容
        /// 私钥（Base64后的）
        /// 返回Base64内容
        private string EncryptByPrivateKey(string data, string privateKey)
        {
            //非对称加密算法，加解密用  
            IAsymmetricBlockCipher engine = new Pkcs1Encoding(new RsaEngine());

            //加密  
            try
            {
                engine.Init(true, GetPrivateKeyParameter(privateKey));
                byte[] byteData = Encoding_UTF8.GetBytes(data);
                var ResultData = engine.ProcessBlock(byteData, 0, byteData.Length);
                return Convert.ToBase64String(ResultData);
                //Console.WriteLine("密文（base64编码）:" + Convert.ToBase64String(testData) + Environment.NewLine);
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
        #endregion

        #region 使用私钥解密内容
        /// 

        /// 私钥解密
        /// 
        /// 待解密的内容
        /// 私钥（Base64编码后的）
        /// 返回明文
        private string DecryptByPrivateKey(string data, string privateKey)
        {
            data = data.Replace("r", "").Replace("n", "").Replace(" ", "");
            //非对称加密算法，加解密用  
            IAsymmetricBlockCipher engine = new Pkcs1Encoding(new RsaEngine());

            //解密  
            try
            {
                engine.Init(false, GetPrivateKeyParameter(privateKey));
                byte[] byteData = Convert.FromBase64String(data);
                var ResultData = engine.ProcessBlock(byteData, 0, byteData.Length);
                return Encoding_UTF8.GetString(ResultData);
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
        #endregion

        #region 使用公钥加密内容
        /// 

        /// 公钥加密
        /// 
        /// 加密内容
        /// 公钥（Base64编码后的）
        /// 返回Base64内容
        private string EncryptByPublicKey(string data, string publicKey)
        {
            //非对称加密算法，加解密用  
            IAsymmetricBlockCipher engine = new Pkcs1Encoding(new RsaEngine());

            //加密  
            try
            {
                engine.Init(true, GetPublicKeyParameter(publicKey));
                byte[] byteData = Encoding_UTF8.GetBytes(data);
                var ResultData = engine.ProcessBlock(byteData, 0, byteData.Length);
                return Convert.ToBase64String(ResultData);
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
        #endregion

        #region 使用公钥解密内容
        /// 

        /// 公钥解密
        /// 
        /// 待解密的内容
        /// 公钥（Base64编码后的）
        /// 返回明文
        private string DecryptByPublicKey(string data, string publicKey)
        {
            data = data.Replace("r", "").Replace("n", "").Replace(" ", "");
            //非对称加密算法，加解密用  
            IAsymmetricBlockCipher engine = new Pkcs1Encoding(new RsaEngine());

            //解密  
            try
            {
                engine.Init(false, GetPublicKeyParameter(publicKey));
                byte[] byteData = Convert.FromBase64String(data);
                var ResultData = engine.ProcessBlock(byteData, 0, byteData.Length);
                return Encoding_UTF8.GetString(ResultData);

            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
        #endregion
    }
}

对应的IRSAHelper接口，这里主要是MEF依赖注入用，所以写了个接口：

namespace Cari.Safety.SSO.Interface
{
    /// 

    /// Summary: RSAHelper接口
    /// Author: Lee Liu
    /// Date: 20181031
    /// 
    public interface IRSAHelper
    {
        /// 

        /// 使用私钥解密
        /// 
        /// 要解密的数据
        /// 私钥
        /// 明文
        string DecryptViaPrivateKey(string data, string privateKey);

        /// 

        /// 使用公钥解密
        /// 
        /// 要解密的数据
        /// 公钥
        /// 明文
        string DecryptViaPublicKey(string data, string publicKey);

        /// 

        /// 使用私钥加密
        /// 
        /// 要加密的数据
        /// 私钥
        /// 密文
        string EncryptViaPrivateKey(string data, string privateKey);

        /// 

        /// 使用公钥加密
        /// 
        /// 要加密的数据
        /// 公钥
        /// 密文
        string EncryptViaPublicKey(string data, string publicKey);

        /// 

        /// 获取公钥
        /// 
        /// 返回公钥字符串
        string GetPublicKey();

        /// 

        /// 获取私钥
        /// 
        /// 返回私钥字符串
        string GetPrivateKey();

        /// 

        /// 设置公钥
        /// 
        /// 公钥
        void SetPublicKey(string publicKey);

        /// 

        /// 设置私钥
        /// 
        /// 私钥
        void SetPrivateKey(string privateKey);
    }
}