基于RSA的数字签名和验证C#源码

/* 备注： * 若要使用公钥系统对消息进行数字签名，发送方先向该消息应用哈希函数以创建消息摘要。 * 然后，发送方用自己的私钥对消息摘要进行加密，以创建发送方的个人签名。在收到消息和 * 签名后，接收方使用发送方的公钥解密该签名，以恢复消息摘要，并使用发送方所用的同一 * 哈希算法对该消息进行哈希运算。如果接收方计算的消息摘要与从发送方收到的消息摘要完 * 全匹配，则接收方可以假定消息在传输中未被更改。请注意，因为发送方的公钥是公共知识， * 所以任何人都可以验证签名。 */using System;using System.Security.Cryptography;using System.Text;class RSACSPSample{ static void Main() { try { string str_DataToSign = @"Data to Sign!Data to Sign!Data to Sign!"; Console.WriteLine("原文：" str_DataToSign); Console.WriteLine("长度：" str_DataToSign.Length.ToString()); Console.WriteLine(); RSACryptoServiceProvider RSAalg = new RSACryptoServiceProvider(); string str_Private_Key = Convert.ToBase64String( RSAalg.ExportCspBlob(true) ); string str_Public_Key = Convert.ToBase64String( RSAalg.ExportCspBlob(false) ); Console.WriteLine("公钥：" str_Public_Key); Console.WriteLine(); Console.WriteLine("私钥：" str_Private_Key); Console.WriteLine(); string str_SignedData = HashAndSign(str_DataToSign, str_Private_Key);// Hash and sign the data. Console.WriteLine("签名数据：" str_SignedData); Console.WriteLine(); if (VerifySignedHash(str_DataToSign, str_SignedData, str_Public_Key)) { Console.WriteLine("验证签名OK."); } else { Console.WriteLine("签名不匹配!"); } Console.WriteLine(); } catch (ArgumentNullException) { Console.WriteLine("The data was not signed or verified"); } } //对数据签名 public static string HashAndSign(string str_DataToSign, string str_Private_Key) { ASCIIEncoding ByteConverter = new ASCIIEncoding(); byte[] DataToSign = ByteConverter.GetBytes(str_DataToSign); try { RSACryptoServiceProvider RSAalg = new RSACryptoServiceProvider(); RSAalg.ImportCspBlob( Convert.FromBase64String(str_Private_Key) ); byte[] signedData = RSAalg.SignData(DataToSign, new SHA1CryptoServiceProvider()); string str_SignedData = Convert.ToBase64String(signedData); return str_SignedData; } catch (CryptographicException e) { Console.WriteLine(e.Message); return null; } } //验证签名 public static bool VerifySignedHash(string str_DataToVerify, string str_SignedData, string str_Public_Key) { byte[] SignedData = Convert.FromBase64String(str_SignedData); ASCIIEncoding ByteConverter = new ASCIIEncoding(); byte[] DataToVerify = ByteConverter.GetBytes(str_DataToVerify); try { RSACryptoServiceProvider RSAalg = new RSACryptoServiceProvider(); RSAalg.ImportCspBlob( Convert.FromBase64String(str_Public_Key) ); return RSAalg.VerifyData(DataToVerify, new SHA1CryptoServiceProvider(), SignedData); } catch (CryptographicException e) { Console.WriteLine(e.Message); return false; } }}