使用類庫：“BouncyCastle.NetCore”（.Net FrameWork使用“BouncyCastle”）
/// <summary>
/// 生成PEM格式的公鑰和密鑰
/// </summary>
/// <param name="strength">長度</param>
/// <returns>Item1:公鑰；Item2:私鑰；</returns>
public static (string, string) CreateKeyPair(int strength = 1024)
{
RsaKeyPairGenerator r = new RsaKeyPairGenerator();
r.Init(new KeyGenerationParameters(new SecureRandom(), strength));
AsymmetricCipherKeyPair keys = r.GenerateKeyPair();
TextWriter privateTextWriter = new StringWriter();
PemWriter privatePemWriter = new PemWriter(privateTextWriter);
privatePemWriter.WriteObject(keys.Private);
privatePemWriter.Writer.Flush();
TextWriter publicTextWriter = new StringWriter();
PemWriter publicPemWriter = new PemWriter(publicTextWriter);
publicPemWriter.WriteObject(keys.Public);
publicPemWriter.Writer.Flush();
return (publicTextWriter.ToString(), privateTextWriter.ToString());
}
/// <summary>
/// RSA解密
/// </summary>
/// <param name="privateKey">私鑰</param>
/// <param name="decryptstring">待解密的字符串(Base64)</param>
/// <returns>解密后的字符串</returns>
public static string Decrypt(string privateKey, string decryptstring)
{
using (TextReader reader = new StringReader(privateKey))
{
dynamic key = new PemReader(reader).ReadObject();
var rsaDecrypt = new Pkcs1Encoding(new RsaEngine());
if (key is AsymmetricKeyParameter)
{
key = (AsymmetricKeyParameter)key;
}
else if (key is AsymmetricCipherKeyPair)
{
key = ((AsymmetricCipherKeyPair)key).Private;
}
rsaDecrypt.Init(false, key); //這里加密是true；解密是false
byte[] entData = Convert.FromBase64String(decryptstring);
entData = rsaDecrypt.ProcessBlock(entData, 0, entData.Length);
return Encoding.UTF8.GetString(entData);
}
}
如果想私鑰加密，公鑰解密可以引用類庫：“BouncyCastle.Crypto”,參考地址如下：
https://www.cnblogs.com/dj258/p/6049786.html
前端
前端引用jsencrypt.js
function RSAEncryption(key, encryptstring) { //rsa加密隨機密鑰 var rsa = new JSEncrypt(); //設置后端接口傳回的公鑰（無需對公鑰字符串做任何處理） rsa.setPublicKey(key); //注意：RSA加解密有大小限制（最多117 bytes） var rsaEncrypted = rsa.encrypt(encryptstring); //已加密的字符串（Base64） return rsaEncrypted; }
PEM格式存在換行，因此建議把公鑰放在隱藏域中：<input id="encryption" name="encryption" type="hidden" value="@ViewData["publicKey"]">
原文地址：https://www.cnblogs.com/NBDWDYS2214143926/p/13329231.html