1.RSA加密解密：
(1)获取密钥，这里是产生密钥，实际应用中可以从各种存储介质上读取密钥 (2)加密 (3)解密
2.RSA签名和验证
(1)获取密钥，这里是产生密钥，实际应用中可以从各种存储介质上读取密钥 (2)获取待签名的Hash码 (3)获取签名的字符串 (4)验证
3.公钥与私钥的理解：
(1)私钥用来进行解密和签名，是给自己用的。
(2)公钥由本人公开，用于加密和验证签名，是给别人用的。
(3)当该用户发送文件时，用私钥签名，别人用他给的公钥验证签名，可以保证该信息是由他发送的。当该用户接受文件时，别人用他的公钥加密，他用私钥解密，可以保证该信息只能由他接收到。
class RSACryption { #region RSA 加密解密 #region RSA 的密钥产生 /// <summary> /// RSA产生密钥 /// </summary> /// <param name="xmlKeys">私钥</param> /// <param name="xmlPublicKey">公钥</param> public void RSAKey(out string xmlKeys, out string xmlPublicKey) { try { System.Security.Cryptography.RSACryptoServiceProvider rsa = new RSACryptoServiceProvider(); xmlKeys = rsa.ToXmlString(true); xmlPublicKey = rsa.ToXmlString(false); } catch (Exception ex) { throw ex; } } #endregion #region RSA加密函数 //############################################################################## //RSA 方式加密 //KEY必须是XML的形式,返回的是字符串 //该加密方式有长度限制的！ //############################################################################## /// <summary> /// RSA的加密函数 /// </summary> /// <param name="xmlPublicKey">公钥</param> /// <param name="encryptString">待加密的字符串</param> /// <returns></returns> public string RSAEncrypt(string xmlPublicKey, string encryptString) { try { byte[] PlainTextBArray; byte[] CypherTextBArray; string Result; System.Security.Cryptography.RSACryptoServiceProvider rsa = new RSACryptoServiceProvider(); rsa.FromXmlString(xmlPublicKey); PlainTextBArray = (new UnicodeEncoding()).GetBytes(encryptString); CypherTextBArray = rsa.Encrypt(PlainTextBArray, false); Result = Convert.ToBase64String(CypherTextBArray); return Result; } catch (Exception ex) { throw ex; } } /// <summary> /// RSA的加密函数 /// </summary> /// <param name="xmlPublicKey">公钥</param> /// <param name="EncryptString">待加密的字节数组</param> /// <returns></returns> public string RSAEncrypt(string xmlPublicKey, byte[] EncryptString) { try { byte[] CypherTextBArray; string Result; System.Security.Cryptography.RSACryptoServiceProvider rsa = new RSACryptoServiceProvider(); rsa.FromXmlString(xmlPublicKey); CypherTextBArray = rsa.Encrypt(EncryptString, false); Result = Convert.ToBase64String(CypherTextBArray); return Result; } catch (Exception ex) { throw ex; } } #endregion #region RSA的解密函数 /// <summary> /// RSA的解密函数 /// </summary> /// <param name="xmlPrivateKey">私钥</param> /// <param name="decryptString">待解密的字符串</param> /// <returns></returns> public string RSADecrypt(string xmlPrivateKey, string decryptString) { try { byte[] PlainTextBArray; byte[] DypherTextBArray; string Result; System.Security.Cryptography.RSACryptoServiceProvider rsa = new RSACryptoServiceProvider(); rsa.FromXmlString(xmlPrivateKey); PlainTextBArray = Convert.FromBase64String(decryptString); DypherTextBArray = rsa.Decrypt(PlainTextBArray, false); Result = (new UnicodeEncoding()).GetString(DypherTextBArray); return Result; } catch (Exception ex) { throw ex; } } /// <summary> /// RSA的解密函数 /// </summary> /// <param name="xmlPrivateKey">私钥</param> /// <param name="DecryptString">待解密的字节数组</param> /// <returns></returns> public string RSADecrypt(string xmlPrivateKey, byte[] DecryptString) { try { byte[] DypherTextBArray; string Result; System.Security.Cryptography.RSACryptoServiceProvider rsa = new RSACryptoServiceProvider(); rsa.FromXmlString(xmlPrivateKey); DypherTextBArray = rsa.Decrypt(DecryptString, false); Result = (new UnicodeEncoding()).GetString(DypherTextBArray); return Result; } catch (Exception ex) { throw ex; } } #endregion #endregion #region RSA数字签名 #region 获取Hash描述表 /// <summary> /// 获取Hash描述表 /// </summary> /// <param name="strSource">待签名的字符串</param> /// <param name="HashData">Hash描述</param> /// <returns></returns> public bool GetHash(string strSource, ref byte[] HashData) { try { byte[] Buffer; System.Security.Cryptography.HashAlgorithm MD5 = System.Security.Cryptography.HashAlgorithm.Create("MD5"); Buffer = System.Text.Encoding.GetEncoding("GB2312").GetBytes(strSource); HashData = MD5.ComputeHash(Buffer); return true; } catch (Exception ex) { throw ex; } } /// <summary> /// 获取Hash描述表 /// </summary> /// <param name="strSource">待签名的字符串</param> /// <param name="strHashData">Hash描述</param> /// <returns></returns> public bool GetHash(string strSource, ref string strHashData) { try { //从字符串中取得Hash描述 byte[] Buffer; byte[] HashData; System.Security.Cryptography.HashAlgorithm MD5 = System.Security.Cryptography.HashAlgorithm.Create("MD5"); Buffer = System.Text.Encoding.GetEncoding("GB2312").GetBytes(strSource); HashData = MD5.ComputeHash(Buffer); strHashData = Convert.ToBase64String(HashData); return true; } catch (Exception ex) { throw ex; } } /// <summary> /// 获取Hash描述表 /// </summary> /// <param name="objFile">待签名的文件</param> /// <param name="HashData">Hash描述</param> /// <returns></returns> public bool GetHash(System.IO.FileStream objFile, ref byte[] HashData) { try { //从文件中取得Hash描述 System.Security.Cryptography.HashAlgorithm MD5 = System.Security.Cryptography.HashAlgorithm.Create("MD5"); HashData = MD5.ComputeHash(objFile); objFile.Close(); return true; } catch (Exception ex) { throw ex; } } /// <summary> /// 获取Hash描述表 /// </summary> /// <param name="objFile">待签名的文件</param> /// <param name="strHashData">Hash描述</param> /// <returns></returns> public bool GetHash(System.IO.FileStream objFile, ref string strHashData) { try { //从文件中取得Hash描述 byte[] HashData; System.Security.Cryptography.HashAlgorithm MD5 = System.Security.Cryptography.HashAlgorithm.Create("MD5"); HashData = MD5.ComputeHash(objFile); objFile.Close(); strHashData = Convert.ToBase64String(HashData); return true; } catch (Exception ex) { throw ex; } } #endregion #region RSA签名 /// <summary> /// RSA签名 /// </summary> /// <param name="strKeyPrivate">私钥</param> /// <param name="HashbyteSignature">待签名Hash描述</param> /// <param name="EncryptedSignatureData">签名后的结果</param> /// <returns></returns> public bool SignatureFormatter(string strKeyPrivate, byte[] HashbyteSignature, ref byte[] EncryptedSignatureData) { try { System.Security.Cryptography.RSACryptoServiceProvider RSA = new System.Security.Cryptography.RSACryptoServiceProvider(); RSA.FromXmlString(strKeyPrivate); System.Security.Cryptography.RSAPKCS1SignatureFormatter RSAFormatter = new System.Security.Cryptography.RSAPKCS1SignatureFormatter(RSA); //设置签名的算法为MD5 RSAFormatter.SetHashAlgorithm("MD5"); //执行签名 EncryptedSignatureData = RSAFormatter.CreateSignature(HashbyteSignature); return true; } catch (Exception ex) { throw ex; } } /// <summary> /// RSA签名 /// </summary> /// <param name="strKeyPrivate">私钥</param> /// <param name="HashbyteSignature">待签名Hash描述</param> /// <param name="m_strEncryptedSignatureData">签名后的结果</param> /// <returns></returns> public bool SignatureFormatter(string strKeyPrivate, byte[] HashbyteSignature, ref string strEncryptedSignatureData) { try { byte[] EncryptedSignatureData; System.Security.Cryptography.RSACryptoServiceProvider RSA = new System.Security.Cryptography.RSACryptoServiceProvider(); RSA.FromXmlString(strKeyPrivate); System.Security.Cryptography.RSAPKCS1SignatureFormatter RSAFormatter = new System.Security.Cryptography.RSAPKCS1SignatureFormatter(RSA); //设置签名的算法为MD5 RSAFormatter.SetHashAlgorithm("MD5"); //执行签名 EncryptedSignatureData = RSAFormatter.CreateSignature(HashbyteSignature); strEncryptedSignatureData = Convert.ToBase64String(EncryptedSignatureData); return true; } catch (Exception ex) { throw ex; } } /// <summary> /// RSA签名 /// </summary> /// <param name="strKeyPrivate">私钥</param> /// <param name="strHashbyteSignature">待签名Hash描述</param> /// <param name="EncryptedSignatureData">签名后的结果</param> /// <returns></returns> public bool SignatureFormatter(string strKeyPrivate, string strHashbyteSignature, ref byte[] EncryptedSignatureData) { try { byte[] HashbyteSignature; HashbyteSignature = Convert.FromBase64String(strHashbyteSignature); System.Security.Cryptography.RSACryptoServiceProvider RSA = new System.Security.Cryptography.RSACryptoServiceProvider(); RSA.FromXmlString(strKeyPrivate); System.Security.Cryptography.RSAPKCS1SignatureFormatter RSAFormatter = new System.Security.Cryptography.RSAPKCS1SignatureFormatter(RSA); //设置签名的算法为MD5 RSAFormatter.SetHashAlgorithm("MD5"); //执行签名 EncryptedSignatureData = RSAFormatter.CreateSignature(HashbyteSignature); return true; } catch (Exception ex) { throw ex; } } /// <summary> /// RSA签名 /// </summary> /// <param name="strKeyPrivate">私钥</param> /// <param name="strHashbyteSignature">待签名Hash描述</param> /// <param name="strEncryptedSignatureData">签名后的结果</param> /// <returns></returns> public bool SignatureFormatter(string strKeyPrivate, string strHashbyteSignature, ref string strEncryptedSignatureData) { try { byte[] HashbyteSignature; byte[] EncryptedSignatureData; HashbyteSignature = Convert.FromBase64String(strHashbyteSignature); System.Security.Cryptography.RSACryptoServiceProvider RSA = new System.Security.Cryptography.RSACryptoServiceProvider(); RSA.FromXmlString(strKeyPrivate); System.Security.Cryptography.RSAPKCS1SignatureFormatter RSAFormatter = new System.Security.Cryptography.RSAPKCS1SignatureFormatter(RSA); //设置签名的算法为MD5 RSAFormatter.SetHashAlgorithm("MD5"); //执行签名 EncryptedSignatureData = RSAFormatter.CreateSignature(HashbyteSignature); strEncryptedSignatureData = Convert.ToBase64String(EncryptedSignatureData); return true; } catch (Exception ex) { throw ex; } } #endregion #region RSA 签名验证 /// <summary> /// RSA签名验证 /// </summary> /// <param name="strKeyPublic">公钥</param> /// <param name="HashbyteDeformatter">Hash描述</param> /// <param name="DeformatterData">签名后的结果</param> /// <returns></returns> public bool SignatureDeformatter(string strKeyPublic, byte[] HashbyteDeformatter, byte[] DeformatterData) { try { System.Security.Cryptography.RSACryptoServiceProvider RSA = new System.Security.Cryptography.RSACryptoServiceProvider(); RSA.FromXmlString(strKeyPublic); System.Security.Cryptography.RSAPKCS1SignatureDeformatter RSADeformatter = new System.Security.Cryptography.RSAPKCS1SignatureDeformatter(RSA); //指定解密的时候HASH算法为MD5 RSADeformatter.SetHashAlgorithm("MD5"); if (RSADeformatter.VerifySignature(HashbyteDeformatter, DeformatterData)) { return true; } else { return false; } } catch (Exception ex) { throw ex; } } /// <summary> /// RSA签名验证 /// </summary> /// <param name="strKeyPublic">公钥</param> /// <param name="strHashbyteDeformatter">Hash描述</param> /// <param name="DeformatterData">签名后的结果</param> /// <returns></returns> public bool SignatureDeformatter(string strKeyPublic, string strHashbyteDeformatter, byte[] DeformatterData) { try { byte[] HashbyteDeformatter; HashbyteDeformatter = Convert.FromBase64String(strHashbyteDeformatter); System.Security.Cryptography.RSACryptoServiceProvider RSA = new System.Security.Cryptography.RSACryptoServiceProvider(); RSA.FromXmlString(strKeyPublic); System.Security.Cryptography.RSAPKCS1SignatureDeformatter RSADeformatter = new System.Security.Cryptography.RSAPKCS1SignatureDeformatter(RSA); //指定解密的时候HASH算法为MD5 RSADeformatter.SetHashAlgorithm("MD5"); if (RSADeformatter.VerifySignature(HashbyteDeformatter, DeformatterData)) { return true; } else { return false; } } catch (Exception ex) { throw ex; } } /// <summary> /// RSA签名验证 /// </summary> /// <param name="strKeyPublic">公钥</param> /// <param name="HashbyteDeformatter">Hash描述</param> /// <param name="strDeformatterData">签名后的结果</param> /// <returns></returns> public bool SignatureDeformatter(string strKeyPublic, byte[] HashbyteDeformatter, string strDeformatterData) { try { byte[] DeformatterData; System.Security.Cryptography.RSACryptoServiceProvider RSA = new System.Security.Cryptography.RSACryptoServiceProvider(); RSA.FromXmlString(strKeyPublic); System.Security.Cryptography.RSAPKCS1SignatureDeformatter RSADeformatter = new System.Security.Cryptography.RSAPKCS1SignatureDeformatter(RSA); //指定解密的时候HASH算法为MD5 RSADeformatter.SetHashAlgorithm("MD5"); DeformatterData = Convert.FromBase64String(strDeformatterData); if (RSADeformatter.VerifySignature(HashbyteDeformatter, DeformatterData)) { return true; } else { return false; } } catch (Exception ex) { throw ex; } } /// <summary> /// RSA签名验证 /// </summary> /// <param name="strKeyPublic">公钥</param> /// <param name="strHashbyteDeformatter">Hash描述</param> /// <param name="strDeformatterData">签名后的结果</param> /// <returns></returns> public bool SignatureDeformatter(string strKeyPublic, string strHashbyteDeformatter, string strDeformatterData) { try { byte[] DeformatterData; byte[] HashbyteDeformatter; HashbyteDeformatter = Convert.FromBase64String(strHashbyteDeformatter); System.Security.Cryptography.RSACryptoServiceProvider RSA = new System.Security.Cryptography.RSACryptoServiceProvider(); RSA.FromXmlString(strKeyPublic); System.Security.Cryptography.RSAPKCS1SignatureDeformatter RSADeformatter = new System.Security.Cryptography.RSAPKCS1SignatureDeformatter(RSA); //指定解密的时候HASH算法为MD5 RSADeformatter.SetHashAlgorithm("MD5"); DeformatterData = Convert.FromBase64String(strDeformatterData); if (RSADeformatter.VerifySignature(HashbyteDeformatter, DeformatterData)) { return true; } else { return false; } } catch (Exception ex) { throw ex; } } #endregion #endregion }
原文：http://www.cnblogs.com/lonelyxmas/p/5507238.html