C#使用BouncyCastle來實現私鑰加密公鑰解密的方法與java互通的RSA加解密和簽名（轉）
阿新 • • 發佈：2021-01-20
因為C#的RSA加密解密只有公鑰加密，私鑰解密，沒有私鑰加密，公鑰解密。在網上查了很久也沒有很好的實現。BouncyCastle的文件少之又少。很多人可能會說，C#也是可以的，通過Biginteger開源類來實現，不過那個是有一個文章，不過他加密出來的是16進位制結果的。根本不能和JAVA互通。連加密出來的都不和C#原生的加密出來的結果格式一樣。所以還是沒有好的解決方法。
接下來還是不斷的找資料，找方法。找朋友找同事。個個都找。問題是有的，方法也是有的，所以總結各路大神之後寫了這個類。實現了私鑰加密，公鑰解密。並通過線上的校驗之後，釋出上來。大家可以做一個DEMO，然後進去線上RSA加密解密校驗。
線上RSA，DES等加密解密地址：
https://the-x.cn/cryptography/Rsa.aspx
http://tool.chacuo.net/cryptrsapubkey
可以直接nuget搜尋BouncyCastle，安裝即可
下面是程式碼：
using System; using System.Collections.Generic; using System.Linq; using System.Text; using Org.BouncyCastle.Asn1.Pkcs; using Org.BouncyCastle.Asn1.X509; using Org.BouncyCastle.Crypto.Generators;using Org.BouncyCastle.Crypto.Parameters; using Org.BouncyCastle.Math; using Org.BouncyCastle.Pkcs; using Org.BouncyCastle.Security; using Org.BouncyCastle.Crypto.Engines; using Org.BouncyCastle.X509; using Org.BouncyCastle.Crypto; using Org.BouncyCastle.Asn1; using Org.BouncyCastle.Crypto.Encodings;using System.IO; namespace Tool { public class RSATool { public RSATool() { } /// <summary> /// KEY 結構體 /// </summary> public struct RSAKEY { /// <summary> /// 公鑰 /// </summary> public string PublicKey { get; set; } /// <summary> /// 私鑰 /// </summary> public string PrivateKey { get; set; } } public RSAKEY GetKey() { //RSA金鑰對的構造器 RsaKeyPairGenerator keyGenerator = new RsaKeyPairGenerator(); //RSA金鑰構造器的引數 RsaKeyGenerationParameters param = new RsaKeyGenerationParameters( Org.BouncyCastle.Math.BigInteger.ValueOf(3), new Org.BouncyCastle.Security.SecureRandom(), 1024, //金鑰長度 25); //用引數初始化金鑰構造器 keyGenerator.Init(param); //產生金鑰對 AsymmetricCipherKeyPair keyPair = keyGenerator.GenerateKeyPair(); //獲取公鑰和金鑰 AsymmetricKeyParameter publicKey = keyPair.Public; AsymmetricKeyParameter privateKey = keyPair.Private; SubjectPublicKeyInfo subjectPublicKeyInfo = SubjectPublicKeyInfoFactory.CreateSubjectPublicKeyInfo(publicKey); PrivateKeyInfo privateKeyInfo = PrivateKeyInfoFactory.CreatePrivateKeyInfo(privateKey); Asn1Object asn1ObjectPublic = subjectPublicKeyInfo.ToAsn1Object(); byte[] publicInfoByte = asn1ObjectPublic.GetEncoded("UTF-8"); Asn1Object asn1ObjectPrivate = privateKeyInfo.ToAsn1Object(); byte[] privateInfoByte = asn1ObjectPrivate.GetEncoded("UTF-8"); RSAKEY item = new RSAKEY() { PublicKey = Convert.ToBase64String(publicInfoByte), PrivateKey = Convert.ToBase64String(privateInfoByte) }; return item; } private AsymmetricKeyParameter GetPublicKeyParameter(string s) { s = s.Replace("\r", "").Replace("\n", "").Replace(" ", ""); byte[] publicInfoByte = Convert.FromBase64String(s); Asn1Object pubKeyObj = Asn1Object.FromByteArray(publicInfoByte);//這裡也可以從流中讀取，從本地匯入 AsymmetricKeyParameter pubKey = PublicKeyFactory.CreateKey(publicInfoByte); return pubKey; } private AsymmetricKeyParameter GetPrivateKeyParameter(string s) { s = s.Replace("\r", "").Replace("\n", "").Replace(" ", ""); byte[] privateInfoByte = Convert.FromBase64String(s); // Asn1Object priKeyObj = Asn1Object.FromByteArray(privateInfoByte);//這裡也可以從流中讀取，從本地匯入 // PrivateKeyInfo privateKeyInfo = PrivateKeyInfoFactory.CreatePrivateKeyInfo(privateKey); AsymmetricKeyParameter priKey = PrivateKeyFactory.CreateKey(privateInfoByte); return priKey; } public string EncryptByKey(string s, string key, bool isPublic) { //非對稱加密演算法，加解密用 IAsymmetricBlockCipher engine = new Pkcs1Encoding(new RsaEngine()); //加密 try { engine.Init(true, isPublic ? GetPublicKeyParameter(key) : GetPrivateKeyParameter(key)); byte[] byteData = System.Text.Encoding.UTF8.GetBytes(s); int inputLen = byteData.Length; MemoryStream ms = new MemoryStream(); int offSet = 0; byte[] cache; int i = 0; // 對資料分段加密 while (inputLen - offSet > 0) { if (inputLen - offSet > 117) { cache = engine.ProcessBlock(byteData, offSet, 117); } else { cache = engine.ProcessBlock(byteData, offSet, inputLen - offSet); } ms.Write(cache, 0, cache.Length); i++; offSet = i * 117; } byte[] encryptedData = ms.ToArray(); //var ResultData = engine.ProcessBlock(byteData, 0, byteData.Length); return Convert.ToBase64String(encryptedData); //Console.WriteLine("密文（base64編碼）:" + Convert.ToBase64String(testData) + Environment.NewLine); } catch (Exception ex) { return ex.Message; } } /// <summary> /// 解密 /// </summary> /// <param name="s"></param> /// <param name="key"></param> /// <param name="isPublic"></param> /// <returns></returns> public string DecryptByPublicKey(string s, string key, bool isPublic) { s = s.Replace("\r", "").Replace("\n", "").Replace(" ", ""); //非對稱加密演算法，加解密用 IAsymmetricBlockCipher engine = new Pkcs1Encoding(new RsaEngine()); //加密 try { engine.Init(false, isPublic ? GetPublicKeyParameter(key) : GetPrivateKeyParameter(key)); byte[] byteData = Convert.FromBase64String(s); int inputLen = byteData.Length; MemoryStream ms = new MemoryStream(); int offSet = 0; byte[] cache; int i = 0; // 對資料分段加密 while (inputLen - offSet > 0) { if (inputLen - offSet > 128) { cache = engine.ProcessBlock(byteData, offSet, 128); } else { cache = engine.ProcessBlock(byteData, offSet, inputLen - offSet); } ms.Write(cache, 0, cache.Length); i++; offSet = i * 128; } byte[] encryptedData = ms.ToArray(); //var ResultData = engine.ProcessBlock(byteData, 0, byteData.Length); return Encoding.UTF8.GetString(ms.ToArray()); //Console.WriteLine("密文（base64編碼）:" + Convert.ToBase64String(testData) + Environment.NewLine); } catch (Exception ex) { return ex.Message; } } /// <summary> /// 簽名 /// </summary> /// <param name="data">資料</param> /// <param name="key">密匙</param> /// <returns></returns> public string SignByPrivateKey(string data, string key) { AsymmetricKeyParameter priKey = GetPrivateKeyParameter(key); byte[] byteData = System.Text.Encoding.UTF8.GetBytes(data); ISigner normalSig = SignerUtilities.GetSigner("SHA1WithRSA"); normalSig.Init(true, priKey); normalSig.BlockUpdate(byteData, 0, data.Length); byte[] normalResult = normalSig.GenerateSignature(); //簽名結果 return Convert.ToBase64String(normalResult); //return System.Text.Encoding.UTF8.GetString(normalResult); } /// <summary> /// 驗籤 /// </summary> /// <param name="plainData">驗證資料</param> /// <param name="sign">簽名</param> /// <param name="key">公匙</param> /// <returns></returns> public bool ValidationPublicKey(string plainData, string sign, string key) { AsymmetricKeyParameter priKey = GetPublicKeyParameter(key); byte[] signBytes = Convert.FromBase64String(sign); byte[] plainBytes = Encoding.UTF8.GetBytes(plainData); ISigner verifier = SignerUtilities.GetSigner("SHA1WithRSA"); verifier.Init(false, priKey); verifier.BlockUpdate(plainBytes, 0, plainBytes.Length); return verifier.VerifySignature(signBytes); //驗簽結果 } } }
轉https://www.cnblogs.com/AnAng/p/10396296.html