C# 实现 Rsa字符串非对称加密简单例子

C# Rsa加密帮助类\Rsa字符串非对称加密简单例子

本代码是应用于以前就职的一家公司里两个系统对接加密实现的加密算法，对面是java语言我这边是场.net 折腾了很久才实现对接成功，这段核心的rsa加密代码的来源代码里备注的有，代码被我改的有点乱，封装成了一个类原装稍微又些区别，代码实测可用就是需要引用BouncyCastle 的组件库建议nuget上直接引用，单独引用的话需要引用多个dll 少了貌似不行。

加密例子

string p="我是要加密的字符串";
string result= Common.RsaCrypto.Encrypt(p)

解密例子

p =Common.RsaCrypto.Decrypt(result);

网上找到的一段rsa的帮助类已在实际落地项目中验证过可用性

using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;

namespace Common
{
    ////// Rsa加密解密-可逆非对称加密(公钥加密算法)
    /// RSA公钥加密算法是1977年由Ron Rivest、Adi Shamirh和LenAdleman在（美国麻省理工学院）开发的。
    /// 安全性好，性能不如Des
    public static class RsaCrypto
    {
        public static String KEY_ALGORITHM = "RSA";
        #region 加密解密方式一：加密密钥和解密密钥相同

        //参考：https://www.cnblogs.com/guohu/p/5562759.html

        ////// 秘钥：加密、解密（秘钥相同,注意保存）
                //////private static CspParameters GetCspKey()
        {
            CspParameters param = new CspParameters
            {
                KeyContainerName = KEY_ALGORITHM//密匙容器的名称，保持加密解密一致才能解密成功
            };
            return param;
        }

        ////// 加密
                //////明文///编码方式///密文
				public static string Encrypt(string palinData, 
				EncodingStrOrByte.EncodingType encodingType 
				= EncodingStrOrByte.EncodingType.UTF8)
        {
            if (string.IsNullOrWhiteSpace(palinData)) return null;
            using (RSACryptoServiceProvider rsa = new RSACryptoServiceProvider(GetCspKey()))
            {
                byte[] bytes = EncodingStrOrByte.GetByte(palinData, encodingType); //将要加密的字符串转换为指定编码的字节数组
                byte[] encryptData = rsa.Encrypt(bytes, false);//将加密后的字节数据转换为新的加密字节数组
                return Convert.ToBase64String(encryptData);//将加密后的字节数组转换为字符串
            }
        }

        ////// 解密
                //////密文///编码方式///明文
				public static string Decrypt(string encryptData, 
				EncodingStrOrByte.EncodingType encodingType 
				= EncodingStrOrByte.EncodingType.UTF8)
        {
            if (string.IsNullOrWhiteSpace(encryptData)) return null;
            using (RSACryptoServiceProvider rsa = new RSACryptoServiceProvider(GetCspKey()))
            {
                byte[] bytes = Convert.FromBase64String(encryptData);
                byte[] palinData = rsa.Decrypt(bytes, false);
                return EncodingStrOrByte.GetString(palinData, encodingType);
            }
        }
        #endregion

        #region 加密解密方式二：公钥加密/私钥解密

        #region 公/私密钥
        //openssl genrsa -out rsa_1024_priv.pem 1024
        private static readonly string _privateKey = @"MIICeAIBADANBgkqhkiG9w0BAQEFAASCAmIwggJeAgEAAoGBALVcQjHHc35w4s9K3nYTkp/
		eS7VGi/8X
		kNbQwZSAKkgoIbj4NfxMzxumvmhI1UNFYpHKhvYV1Fms5a1aC47D4XytekRI9zFQrYb9kTXVTf0XARmdwv
		PoGk/JmWdsCpxrV8AAVzz8xY0m6OktpBpqcweMBmd72hSX9faniQet2ul9AgMBAAECgYAPsunD91jnBAy
		OFxQEspMJpat2CKJLtZWDEtT+7s06K8cnhMzfhyKSaS+oRU24ogPzTM279Y3JKW9EPzwq4ofdJnjjpef+yq
		ToYey9M5YvhEsJ/KjoeEMCMJ8VEVXaeL6OOIImncKWk9fwDxPMqcKMkmQt8F5j7gxhdp6a+LBCXQJBAPEe
		xjvAu9tN22V4D3GWd3rxyE2+2xdA/7BZ1M3/UPozrfifPdbKcsdzpXkOqbXukhAcRS9OKwMjceIeGfCIWoMC
		QQDAjWV3l0SO4ixvwAU1CgH0knD1oh9Z9x7tjdXWGB6Du0oS5KpzaG2cZmwjPTsGaV5KvQnFVYWnCguyr
		/HgvGv/AkEA1/CsrjTUyPn4Q+57Pkn4JTZGIkKMKk4+72v0JqzCk+EWrDPJCQT0OGX8yubz3IiVbTI0T8Jcy
		QnEYzJ8HquvCwJBALE4sr4aZMhZlOqZwnEpr9kJe5woxlBIaZfdJoYxlsxJ8ghnnBYydEgx4K+iaJQjIN0LFlYg
		u62dSl0BIU9mPMMCQQCQ5dWzJrTrMWAJh9JXw0PSp55we2PC6x36wvGp391lrnSUPP638HcDvlW6q/
		RaXeE/ZJKf3lhlBrcZszAowYIH".Replace("\n", "");

        //openssl rsa -pubout -in rsa_1024_priv.pem -out rsa_1024_pub.pem
        private static readonly string _publicKey = @"MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC5UK1mrA9U5iXYS9OmQlYL7N0Okg/gzDtwS
		WPnyLlgpy
7EC419jQTaWQY2rCqsH1jmO4TrT55keKkchK3s7PKvpnM0hjn4QpzvDJzKaCvESuVAbpGekkYAV
rxLb8Or
S68f0cc+WCOroyKTDfgHxbgQWqDCsScnE/UBsn6Xii/thQIDAQAB".Replace("\n", "");
        #endregion
        ////// 公钥加密
        //////明文///编码方式///string：密文
public static string EncryptByPublicKey(string palinData, 
EncodingStrOrByte.EncodingType encodingType 
		= EncodingStrOrByte.EncodingType.UTF8)
        {
            if (string.IsNullOrWhiteSpace(palinData)) return null;
            RSA rsa = CreateRsaFromPublicKey(_publicKey);
            byte[] palinDataBytes = EncodingStrOrByte.GetByte(palinData, encodingType);
            byte[] encryptDataBytes = rsa.EncryptValue(palinDataBytes);
            return Convert.ToBase64String(encryptDataBytes);
        }

        ////// 私钥解密
                //////密文///编码方式///string：明文
				
				(string encryptData, EncodingStrOrByte.EncodingType encodingType 
				= EncodingStrOrByte.EncodingType.UTF8)
        {
            if (string.IsNullOrWhiteSpace(encryptData)) return null;
            RSA rsa = CreateRsaFromPrivateKey(_privateKey);
            byte[] encryptDataBytes = Convert.FromBase64String(encryptData);
            byte[] palinDataBytes = rsa.DecryptValue(encryptDataBytes);
            return EncodingStrOrByte.GetString(palinDataBytes, encodingType);
        }

        ////// 创建私钥
        private static RSA CreateRsaFromPrivateKey(string privateKey)
        {
            var privateKeyBits = Convert.FromBase64String(privateKey);
            var rsa = RSA.Create();
            var RSAparams = new RSAParameters();

            using (var binr = new BinaryReader(new MemoryStream(privateKeyBits)))
            {
                byte bt = 0;
                ushort twobytes = 0;
                twobytes = binr.ReadUInt16();
                if (twobytes == 0x8130)
                    binr.ReadByte();
                else if (twobytes == 0x8230)
                    binr.ReadInt16();
                else
                    throw new Exception("Unexpected value read binr.ReadUInt16()");

                twobytes = binr.ReadUInt16();
                if (twobytes != 0x0102)
                    throw new Exception("Unexpected version");

                bt = binr.ReadByte();
                if (bt != 0x00)
                    throw new Exception("Unexpected value read binr.ReadByte()");

                RSAparams.Modulus = binr.ReadBytes(GetIntegerSize(binr));
                RSAparams.Exponent = binr.ReadBytes(GetIntegerSize(binr));
                RSAparams.D = binr.ReadBytes(GetIntegerSize(binr));
                RSAparams.P = binr.ReadBytes(GetIntegerSize(binr));
                RSAparams.Q = binr.ReadBytes(GetIntegerSize(binr));
                RSAparams.DP = binr.ReadBytes(GetIntegerSize(binr));
                RSAparams.DQ = binr.ReadBytes(GetIntegerSize(binr));
                RSAparams.InverseQ = binr.ReadBytes(GetIntegerSize(binr));
            }
            rsa.ImportParameters(RSAparams);
            return rsa;
        }

        private static int GetIntegerSize(BinaryReader binr)
        {
            byte bt = 0;
            byte lowbyte = 0x00;
            byte highbyte = 0x00;
            int count = 0;
            bt = binr.ReadByte();
            if (bt != 0x02)
            { return count; }
            bt = binr.ReadByte();
            if (bt == 0x81)
            { count = binr.ReadByte(); }
            else if (bt == 0x82)
            {
                highbyte = binr.ReadByte();
                lowbyte = binr.ReadByte();
                byte[] modint = { lowbyte, highbyte, 0x00, 0x00 };
                count = BitConverter.ToInt32(modint, 0);
            }
            else { count = bt; }
            while (binr.ReadByte() == 0x00)
            {
                count -= 1;
            }
            binr.BaseStream.Seek(-1, SeekOrigin.Current);
            return count;
        }

        ////// 创建公钥
       private static RSA CreateRsaFromPublicKey(string publicKeyString)
        {
            byte[] SeqOID = { 0x30, 0x0D, 0x06, 0x09, 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x01, 0x05, 0x00 };
            byte[] x509key;
            byte[] seq = new byte[15];
            int x509size;

            x509key = Convert.FromBase64String(publicKeyString);
            x509size = x509key.Length;

            using (var mem = new MemoryStream(x509key))
            {
                using (var binr = new BinaryReader(mem))
                {
                    byte bt = 0;
                    ushort twobytes = 0;
                    twobytes = binr.ReadUInt16();
                    if (twobytes == 0x8130)
                        binr.ReadByte();
                    else if (twobytes == 0x8230)
                        binr.ReadInt16();
                    else
                        return null;
                    seq = binr.ReadBytes(15);
                    if (!CompareBytearrays(seq, SeqOID))
                        return null;
                    twobytes = binr.ReadUInt16();
                    if (twobytes == 0x8103)
                        binr.ReadByte();
                    else if (twobytes == 0x8203)
                        binr.ReadInt16();
                    else
                        return null;
                    bt = binr.ReadByte();
                    if (bt != 0x00)
                        return null;
                    twobytes = binr.ReadUInt16();
                    if (twobytes == 0x8130)
                        binr.ReadByte();
                    else if (twobytes == 0x8230)
                        binr.ReadInt16();
                    else
                        return null;
                    twobytes = binr.ReadUInt16();
                    byte lowbyte = 0x00;
                    byte highbyte = 0x00;
                    if (twobytes == 0x8102)
                        lowbyte = binr.ReadByte();
                    else if (twobytes == 0x8202)
                    {
                        highbyte = binr.ReadByte();
                        lowbyte = binr.ReadByte();
                    }
                    else
                        return null;
                    byte[] modint = { lowbyte, highbyte, 0x00, 0x00 };
                    int modsize = BitConverter.ToInt32(modint, 0);
                    int firstbyte = binr.PeekChar();
                    if (firstbyte == 0x00)
                    {
                        binr.ReadByte();
                        modsize -= 1;
                    }
                    byte[] modulus = binr.ReadBytes(modsize);
                    if (binr.ReadByte() != 0x02)
                        return null;
                    int expbytes = (int)binr.ReadByte();
                    byte[] exponent = binr.ReadBytes(expbytes);
                    var rsa = RSA.Create();
                    var rsaKeyInfo = new RSAParameters
                    {
                        Modulus = modulus,
                        Exponent = exponent
                    };
                    rsa.ImportParameters(rsaKeyInfo);
                    return rsa;
                }
            }
        }

        private static bool CompareBytearrays(byte[] a, byte[] b)
        {
            if (a.Length != b.Length)
                return false;
            int i = 0;
            foreach (byte c in a)
            {
                if (c != b[i])
                    return false;
                i++;
            }
            return true;
        }
        #endregion
    }
}


 
namespace SelfHelpPrintingSystemService.Common
{
    ////// 处理编码字符串或字符串
    public static class EncodingStrOrByte
    {
        ////// 编码方式
        public enum EncodingType { UTF7, UTF8, UTF32, Unicode, BigEndianUnicode, ASCII, GB2312 };
        ////// 处理指定编码的字符串，转换字节数组
        public static byte[] GetByte(string str, EncodingType encodingType)
        {
            byte[] bytes = null;
            switch (encodingType)
            {
                //将要加密的字符串转换为指定编码的字节数组
                case EncodingType.UTF7:
                    bytes = Encoding.UTF7.GetBytes(str);
                    break;
                case EncodingType.UTF8:
                    bytes = Encoding.UTF8.GetBytes(str);
                    break;
                case EncodingType.UTF32:
                    bytes = Encoding.UTF32.GetBytes(str);
                    break;
                case EncodingType.Unicode:
                    bytes = Encoding.Unicode.GetBytes(str);
                    break;
                case EncodingType.BigEndianUnicode:
                    bytes = Encoding.BigEndianUnicode.GetBytes(str);
                    break;
                case EncodingType.ASCII:
                    bytes = Encoding.ASCII.GetBytes(str);
                    break;
                case EncodingType.GB2312:
                    bytes = Encoding.Default.GetBytes(str);
                    break;
            }
            return bytes;
        }

        ////// 处理指定编码的字节数组，转换字符串
        public static string GetString(byte[] myByte, EncodingType encodingType)
        {
            string str = null;
            switch (encodingType)
            {
                //将要加密的字符串转换为指定编码的字节数组
                case EncodingType.UTF7:
                    str = Encoding.UTF7.GetString(myByte);
                    break;
                case EncodingType.UTF8:
                    str = Encoding.UTF8.GetString(myByte);
                    break;
                case EncodingType.UTF32:
                    str = Encoding.UTF32.GetString(myByte);
                    break;
                case EncodingType.Unicode:
                    str = Encoding.Unicode.GetString(myByte);
                    break;
                case EncodingType.BigEndianUnicode:
                    str = Encoding.BigEndianUnicode.GetString(myByte);
                    break;
                case EncodingType.ASCII:
                    str = Encoding.ASCII.GetString(myByte);
                    break;
                case EncodingType.GB2312:
                    str = Encoding.Default.GetString(myByte);
                    break;
            }
            return str;
        }
    }
}