RSA-C#

  /*@file rsasample.cs

compiled ok with C#2005 by chinayaosir
本程序直接使用类库Cryptography实现RSA加解密演示
通用加解密原理
M=明文，C=密文，k1=加密钥匙，k2=解密钥匙
E=加密算法， D=解密算法
加密：C=Ek1(M)
解密：M=Dk2(C)=Dk2(Ek1(M))
k1==k2称为对称密码系统,精典代码是DES
k1<>k2称为非对称密码系统，精典代表是RSA

 */

using System;
using System.Collections.Generic;
using System.Text;
using System.Security.Cryptography;

namespace rsa
{
    class Program
    {
        public static void Main()
        {
            try
            {
                string str_Plain_Text = "rsa with c#,very good!" ;
                Console.WriteLine("明文：" + str_Plain_Text);
                Console.WriteLine("长度：" + str_Plain_Text.Length.ToString());
                Console.WriteLine();

                RSACryptoServiceProvider RSA = new RSACryptoServiceProvider();

                string str_Public_Key;
                string str_Private_Key;
                string str_Cypher_Text = RSA_Encrypt(str_Plain_Text, out str_Public_Key, out str_Private_Key);
                Console.WriteLine("密文：/n" + str_Cypher_Text);
                Console.WriteLine("公钥：/n" + str_Public_Key);
                Console.WriteLine("私钥：/n" + str_Private_Key);

                string str_Plain_Text2 = RSA_Decrypt(str_Cypher_Text, str_Private_Key);
                Console.WriteLine("解密：" + str_Plain_Text2);

                Console.ReadLine();
            }
            catch (ArgumentNullException)
            {
                Console.WriteLine("Encryption failed.");
            }
        }

        //随机生成公私密钥对
        //RSA加密函数       
        static public string RSA_Encrypt(string str_Plain_Text, out string str_Public_Key, out string str_Private_Key)
        {
            str_Public_Key = "";
            str_Private_Key = "";
            UnicodeEncoding ByteConverter = new UnicodeEncoding();
            byte[] DataToEncrypt = ByteConverter.GetBytes(str_Plain_Text);
            try
            {
                RSACryptoServiceProvider RSA = new RSACryptoServiceProvider();
                str_Public_Key = Convert.ToBase64String(RSA.ExportCspBlob(false));
                str_Private_Key = Convert.ToBase64String(RSA.ExportCspBlob(true));

                //OAEP padding is only available on Microsoft Windows XP or later. 
                byte[] bytes_Cypher_Text = RSA.Encrypt(DataToEncrypt, false);
                str_Public_Key = Convert.ToBase64String(RSA.ExportCspBlob(false));
                str_Private_Key = Convert.ToBase64String(RSA.ExportCspBlob(true));
                string str_Cypher_Text = Convert.ToBase64String(bytes_Cypher_Text);
                return str_Cypher_Text;
            }
            catch (CryptographicException e)
            {
                Console.WriteLine(e.Message);
                return null;
            }
        }

        //RSA解密函数
        static public string RSA_Decrypt(string str_Cypher_Text, string str_Private_Key)
        {
            byte[] DataToDecrypt = Convert.FromBase64String(str_Cypher_Text);
            try
            {
                RSACryptoServiceProvider RSA = new RSACryptoServiceProvider();
                //RSA.ImportParameters(RSAKeyInfo);
                byte[] bytes_Public_Key = Convert.FromBase64String(str_Private_Key);
                RSA.ImportCspBlob(bytes_Public_Key);

                //OAEP padding is only available on Microsoft Windows XP or later. 
                byte[] bytes_Plain_Text = RSA.Decrypt(DataToDecrypt, false);
                UnicodeEncoding ByteConverter = new UnicodeEncoding();
                string str_Plain_Text = ByteConverter.GetString(bytes_Plain_Text);
                return str_Plain_Text;
            }
            catch (CryptographicException e)
            {
                Console.WriteLine(e.ToString());
                return null;
            }
        }//end RSA_Decrypt

    }
}