RSA非对称 私钥加密

RSA生成公钥和私钥对

 /// <summary>
         /// RSA生成公钥和私钥
         /// </summary>
         /// <returns></returns>
         public static string[] GenerateKeys()
         {
             try
             {
                 string[] sKeys = new String[];
                 RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
                 sKeys[] = rsa.ToXmlString(true);//私钥
                 sKeys[] = rsa.ToXmlString(false);//公钥
                 return sKeys;
             }
             catch (Exception)
             {
                 return null;
             }
         }

RSA私钥格式转换

 public class RSAKeyConvert
     {
         /// <summary>
         /// RSA私钥格式转换，java->.net
         /// </summary>
         /// <param name="privateKey">java生成的RSA私钥</param>
         /// <returns></returns>
         public static string RSAPrivateKeyJava2DotNet(string privateKey)
         {
             RsaPrivateCrtKeyParameters privateKeyParam = (RsaPrivateCrtKeyParameters)PrivateKeyFactory.CreateKey(Convert.FromBase64String(privateKey));

             return string.Format("<RSAKeyValue><Modulus>{0}</Modulus><Exponent>{1}</Exponent><P>{2}</P><Q>{3}</Q><DP>{4}</DP><DQ>{5}</DQ><InverseQ>{6}</InverseQ><D>{7}</D></RSAKeyValue>",
                 Convert.ToBase64String(privateKeyParam.Modulus.ToByteArrayUnsigned()),
                 Convert.ToBase64String(privateKeyParam.PublicExponent.ToByteArrayUnsigned()),
                 Convert.ToBase64String(privateKeyParam.P.ToByteArrayUnsigned()),
                 Convert.ToBase64String(privateKeyParam.Q.ToByteArrayUnsigned()),
                 Convert.ToBase64String(privateKeyParam.DP.ToByteArrayUnsigned()),
                 Convert.ToBase64String(privateKeyParam.DQ.ToByteArrayUnsigned()),
                 Convert.ToBase64String(privateKeyParam.QInv.ToByteArrayUnsigned()),
                 Convert.ToBase64String(privateKeyParam.Exponent.ToByteArrayUnsigned()));
         }

         /// <summary>
         /// RSA私钥格式转换，.net->java
         /// </summary>
         /// <param name="privateKey">.net生成的私钥</param>
         /// <returns></returns>
         public static string RSAPrivateKeyDotNet2Java(string privateKey)
         {
             XmlDocument doc = new XmlDocument();
             doc.LoadXml(privateKey);
             BigInteger m = new BigInteger(, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("Modulus")[].InnerText));
             BigInteger exp = new BigInteger(, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("Exponent")[].InnerText));
             BigInteger d = new BigInteger(, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("D")[].InnerText));
             BigInteger p = new BigInteger(, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("P")[].InnerText));
             BigInteger q = new BigInteger(, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("Q")[].InnerText));
             BigInteger dp = new BigInteger(, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("DP")[].InnerText));
             BigInteger dq = new BigInteger(, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("DQ")[].InnerText));
             BigInteger qinv = new BigInteger(, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("InverseQ")[].InnerText));

             RsaPrivateCrtKeyParameters privateKeyParam = new RsaPrivateCrtKeyParameters(m, exp, d, p, q, dp, dq, qinv);

             PrivateKeyInfo privateKeyInfo = PrivateKeyInfoFactory.CreatePrivateKeyInfo(privateKeyParam);
             byte[] serializedPrivateBytes = privateKeyInfo.ToAsn1Object().GetEncoded();
             return Convert.ToBase64String(serializedPrivateBytes);
         }

         /// <summary>
         /// RSA公钥格式转换，java->.net
         /// </summary>
         /// <param name="publicKey">java生成的公钥</param>
         /// <returns></returns>
         public static string RSAPublicKeyJava2DotNet(string publicKey)
         {
             RsaKeyParameters publicKeyParam = (RsaKeyParameters)PublicKeyFactory.CreateKey(Convert.FromBase64String(publicKey));
             return string.Format("<RSAKeyValue><Modulus>{0}</Modulus><Exponent>{1}</Exponent></RSAKeyValue>",
                 Convert.ToBase64String(publicKeyParam.Modulus.ToByteArrayUnsigned()),
                 Convert.ToBase64String(publicKeyParam.Exponent.ToByteArrayUnsigned()));
         }

         /// <summary>
         /// RSA公钥格式转换，.net->java
         /// </summary>
         /// <param name="publicKey">.net生成的公钥</param>
         /// <returns></returns>
         public static string RSAPublicKeyDotNet2Java(string publicKey)
         {
             XmlDocument doc = new XmlDocument();
             doc.LoadXml(publicKey);
             BigInteger m = new BigInteger(, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("Modulus")[].InnerText));
             BigInteger p = new BigInteger(, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("Exponent")[].InnerText));
             RsaKeyParameters pub = new RsaKeyParameters(false, m, p);

             SubjectPublicKeyInfo publicKeyInfo = SubjectPublicKeyInfoFactory.CreateSubjectPublicKeyInfo(pub);
             byte[] serializedPublicBytes = publicKeyInfo.ToAsn1Object().GetDerEncoded();
             return Convert.ToBase64String(serializedPublicBytes);
         }
     }

私钥加密数据

 /// <summary>
         /// 用私钥给数据进行RSA加密
         /// </summary>
         /// <param name="xmlPrivateKey">私钥</param>
         /// <param name="strEncryptString">待加密数据</param>
         /// <returns>加密后的数据（Base64）</returns>
         public static string RSAEncryptByPrivateKey(string xmlPrivateKey, string strEncryptString)
         {
             //加载私钥
             RSACryptoServiceProvider privateRsa = new RSACryptoServiceProvider();
             privateRsa.FromXmlString(xmlPrivateKey);

             //转换密钥
             AsymmetricCipherKeyPair keyPair = DotNetUtilities.GetKeyPair(privateRsa);

             IBufferedCipher c = CipherUtilities.GetCipher("RSA/ECB/PKCS1Padding");// 参数与Java中加密解密的参数一致
             //第一个参数为true表示加密，为false表示解密；第二个参数表示密钥
             c.Init(true, keyPair.Private);

             byte[] DataToEncrypt = Encoding.UTF8.GetBytes(strEncryptString);
             byte[] outBytes = c.DoFinal(DataToEncrypt);//加密
             string strBase64 = Convert.ToBase64String(outBytes);

             return strBase64;
         }

需要引用BouncyCastle.Crypto.dll