C# Rsa加密（私钥加密、公钥解密、密钥格式转换、支持超大长度分段加密）
此为工具类，这个和java版本的加密对比过了，结果是一样的，代码赋值黏贴直接用，不多比比，直接上代码（需要在nuget上寻找"Portable.BouncyCastle"包安装）：
（java端有个和c#端不一样的地方，base64编码有好几套，有时候对不上大概率是base64那边的问题）
using Org.BouncyCastle.Asn1.Pkcs; using Org.BouncyCastle.Asn1.X509; using Org.BouncyCastle.Crypto; using Org.BouncyCastle.Crypto.Parameters; using Org.BouncyCastle.Math; using Org.BouncyCastle.Pkcs; using Org.BouncyCastle.Security; using Org.BouncyCastle.X509; using System; using System.IO; using System.Security.Cryptography; using System.Text; using System.Xml; public class RSAUtil { /// <summary> /// 生成公钥与私钥方法 /// </summary> /// <returns></returns> public static string[] CreateKey(KeyType keyType, KeySize keySize) { try { string[] sKeys = new string[2]; RSACryptoServiceProvider rsa = new RSACryptoServiceProvider((int)keySize); switch (keyType) { case KeyType.XML: { //私钥 sKeys[0] = rsa.ToXmlString(true); //公钥 sKeys[1] = rsa.ToXmlString(false); } break; case KeyType.PKS8: { sKeys[0] = rsa.ToXmlString(true); //公钥 sKeys[1] = rsa.ToXmlString(false); //JAVA私钥 sKeys[0] = RSAPrivateKeyDotNet2Java(sKeys[0]); //JAVA公钥 sKeys[1] = RSAPublicKeyDotNet2Java(sKeys[1]); } break; default: break; } return sKeys; } catch (Exception ex) { return null; } } /// <summary> /// 密钥类型 /// </summary> public enum KeyType { /// <summary> /// xml类型 /// </summary> XML, /// <summary> /// pks8类型 /// </summary> PKS8 } /// <summary> /// 密钥尺寸(一般都是1024位的) /// </summary> public enum KeySize { SMALL = 1024, BIG = 2048 } /// <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(1, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("Modulus")[0].InnerText)); BigInteger exp = new BigInteger(1, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("Exponent")[0].InnerText)); BigInteger d = new BigInteger(1, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("D")[0].InnerText)); BigInteger p = new BigInteger(1, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("P")[0].InnerText)); BigInteger q = new BigInteger(1, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("Q")[0].InnerText)); BigInteger dp = new BigInteger(1, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("DP")[0].InnerText)); BigInteger dq = new BigInteger(1, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("DQ")[0].InnerText)); BigInteger qinv = new BigInteger(1, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("InverseQ")[0].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，.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(1, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("Modulus")[0].InnerText)); BigInteger p = new BigInteger(1, Convert.FromBase64String(doc.DocumentElement.GetElementsByTagName("Exponent")[0].InnerText)); RsaKeyParameters pub = new RsaKeyParameters(false, m, p); SubjectPublicKeyInfo publicKeyInfo = SubjectPublicKeyInfoFactory.CreateSubjectPublicKeyInfo(pub); byte[] serializedPublicBytes = publicKeyInfo.ToAsn1Object().GetDerEncoded(); return Convert.ToBase64String(serializedPublicBytes); } /// <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 RSAPrivateKeyJavaToDotNet(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公钥格式转换，java->.net /// </summary> /// <param name="publicKey">java生成的公钥</param> /// <returns></returns> public static string RSAPublicKeyJavaToDotNet(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> /// 最大加密长度 /// </summary> private const int MAX_ENCRYPT_BLOCK = 245; /// <summary> /// 最大解密长度 /// </summary> private const int MAX_DECRYPT_BLOCK = 256; /// <summary> /// 用私钥给数据进行RSA加密 /// </summary> /// <param name="xmlPrivateKey"></param> /// <param name="strEncryptString"></param> /// <returns></returns> public static string PrivateKeyEncrypt(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"); //使用RSA/ECB/PKCS1Padding格式 c.Init(true, keyPair.Private);//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 byte[] dataToEncrypt = Encoding.UTF8.GetBytes(strEncryptString);//获取字节 byte[] cache; int time = 0;//次数 int inputLen = dataToEncrypt.Length; int offSet = 0; MemoryStream outStream = new MemoryStream(); while (inputLen - offSet > 0) { if (inputLen - offSet > MAX_ENCRYPT_BLOCK) { cache = c.DoFinal(dataToEncrypt, offSet, MAX_ENCRYPT_BLOCK); } else { cache = c.DoFinal(dataToEncrypt, offSet, inputLen - offSet); } //写入 outStream.Write(cache, 0, cache.Length); time++; offSet = time * MAX_ENCRYPT_BLOCK; } byte[] resData = outStream.ToArray(); string strBase64 = Convert.ToBase64String(resData); outStream.Close(); return strBase64; } /// <summary> /// 用公钥给数据进行RSA解密 /// </summary> /// <param name="xmlPublicKey"> 公钥(XML格式字符串) </param> /// <param name="strDecryptString"> 要解密数据 </param> /// <returns> 解密后的数据 </returns> public static string PublicKeyDecrypt(string xmlPublicKey, string strDecryptString) { //加载公钥 RSACryptoServiceProvider publicRsa = new RSACryptoServiceProvider(); publicRsa.FromXmlString(xmlPublicKey); RSAParameters rp = publicRsa.ExportParameters(false); //转换密钥 AsymmetricKeyParameter pbk = DotNetUtilities.GetRsaPublicKey(rp); IBufferedCipher c = CipherUtilities.GetCipher("RSA/ECB/PKCS1Padding"); //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(false, pbk); byte[] DataToDecrypt = Convert.FromBase64String(strDecryptString); byte[] cache; int time = 0;//次数 int inputLen = DataToDecrypt.Length; int offSet = 0; MemoryStream outStream = new MemoryStream(); while (inputLen - offSet > 0) { if (inputLen - offSet > MAX_DECRYPT_BLOCK) { cache = c.DoFinal(DataToDecrypt, offSet, MAX_DECRYPT_BLOCK); } else { cache = c.DoFinal(DataToDecrypt, offSet, inputLen - offSet); } //写入 outStream.Write(cache, 0, cache.Length); time++; offSet = time * MAX_DECRYPT_BLOCK; } byte[] resData = outStream.ToArray(); string strDec = Encoding.UTF8.GetString(resData); return strDec; } /// <summary> /// 签名 /// </summary> /// <param name="str">需签名的数据</param> /// <returns>签名后的值</returns> public static string Sign(string str, string privateKey, SignAlgType signAlgType) { //根据需要加签时的哈希算法转化成对应的hash字符节 byte[] bt = Encoding.GetEncoding("utf-8").GetBytes(str); byte[] rgbHash = null; switch (signAlgType) { case SignAlgType.SHA256: { SHA256CryptoServiceProvider csp = new SHA256CryptoServiceProvider(); rgbHash = csp.ComputeHash(bt); } break; case SignAlgType.MD5: { MD5CryptoServiceProvider csp = new MD5CryptoServiceProvider(); rgbHash = csp.ComputeHash(bt); } break; case SignAlgType.SHA1: { SHA1 csp = new SHA1CryptoServiceProvider(); rgbHash = csp.ComputeHash(bt); } break; default: break; } RSACryptoServiceProvider key = new RSACryptoServiceProvider(); key.FromXmlString(privateKey); RSAPKCS1SignatureFormatter formatter = new RSAPKCS1SignatureFormatter(key); formatter.SetHashAlgorithm(signAlgType.ToString());//此处是你需要加签的hash算法，需要和上边你计算的hash值的算法一致，不然会报错。 byte[] inArray = formatter.CreateSignature(rgbHash); return Convert.ToBase64String(inArray); } /// <summary> /// 签名验证 /// </summary> /// <param name="str">待验证的字符串</param> /// <param name="sign">加签之后的字符串</param> /// <returns>签名是否符合</returns> public static bool Verify(string str, string sign, string publicKey, SignAlgType signAlgType) { byte[] bt = Encoding.GetEncoding("utf-8").GetBytes(str); byte[] rgbHash = null; switch (signAlgType) { case SignAlgType.SHA256: { SHA256CryptoServiceProvider csp = new SHA256CryptoServiceProvider(); rgbHash = csp.ComputeHash(bt); } break; case SignAlgType.MD5: { MD5CryptoServiceProvider csp = new MD5CryptoServiceProvider(); rgbHash = csp.ComputeHash(bt); } break; case SignAlgType.SHA1: { SHA1 csp = new SHA1CryptoServiceProvider(); rgbHash = csp.ComputeHash(bt); } break; default: break; } RSACryptoServiceProvider key = new RSACryptoServiceProvider(); key.FromXmlString(publicKey); RSAPKCS1SignatureDeformatter deformatter = new RSAPKCS1SignatureDeformatter(key); deformatter.SetHashAlgorithm(signAlgType.ToString()); byte[] rgbSignature = Convert.FromBase64String(sign); if (deformatter.VerifySignature(rgbHash, rgbSignature)) return true; return false; } /// <summary> /// 签名算法类型 /// </summary> public enum SignAlgType { /// <summary> /// sha256 /// </summary> SHA256, /// <summary> /// md5 /// </summary> MD5, /// <summary> /// sha1 /// </summary> SHA1 } }
