Java實現RSA算法的方法詳解

更新時間：2018年03月30日 15:02:57 作者：chengqiuming

這篇文章主要介紹了Java實現RSA算法的方法,結合實例形式分析了RSA算法的原理、實現與使用方法,需要的朋友可以參考下

本文實例講述了Java實現RSA算法的方法。分享給大家供大家參考，具體如下：

一介紹

唯一廣泛接受并實現
用于數據加密和數字簽名
公鑰加密、私鑰解密
私鑰加密、公鑰解密

二 RSA參數說明

三實現

package com.imooc.security.rsa;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import javax.crypto.Cipher;
import org.apache.commons.codec.binary.Base64;
public class ImoocRSA {
  private static String src = "cakin24 security rsa";
  public static void main(String[] args) {
    jdkRSA();
  }
  public static void jdkRSA() {
    try {
      //1.初始化密鑰
      KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
      keyPairGenerator.initialize(512);
      KeyPair keyPair = keyPairGenerator.generateKeyPair();
      RSAPublicKey rsaPublicKey = (RSAPublicKey)keyPair.getPublic();
      RSAPrivateKey rsaPrivateKey = (RSAPrivateKey)keyPair.getPrivate();
      System.out.println("Public Key : " + Base64.encodeBase64String(rsaPublicKey.getEncoded()));
      System.out.println("Private Key : " + Base64.encodeBase64String(rsaPrivateKey.getEncoded()));
      //2.私鑰加密、公鑰解密——加密
      PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(rsaPrivateKey.getEncoded());
      KeyFactory keyFactory = KeyFactory.getInstance("RSA");
      PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
      Cipher cipher = Cipher.getInstance("RSA");
      cipher.init(Cipher.ENCRYPT_MODE, privateKey);
      byte[] result = cipher.doFinal(src.getBytes());
      System.out.println("私鑰加密、公鑰解密——加密 : " + Base64.encodeBase64String(result));
      //3.私鑰加密、公鑰解密——解密
      X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(rsaPublicKey.getEncoded());
      keyFactory = KeyFactory.getInstance("RSA");
      PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
      cipher = Cipher.getInstance("RSA");
      cipher.init(Cipher.DECRYPT_MODE, publicKey);
      result = cipher.doFinal(result);
      System.out.println("私鑰加密、公鑰解密——解密：" + new String(result));
      //4.公鑰加密、私鑰解密——加密
      x509EncodedKeySpec = new X509EncodedKeySpec(rsaPublicKey.getEncoded());
      keyFactory = KeyFactory.getInstance("RSA");
      publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
      cipher = Cipher.getInstance("RSA");
      cipher.init(Cipher.ENCRYPT_MODE, publicKey);
      result = cipher.doFinal(src.getBytes());
      System.out.println("公鑰加密、私鑰解密——加密 : " + Base64.encodeBase64String(result));
      //5.公鑰加密、私鑰解密——解密
      pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(rsaPrivateKey.getEncoded());
      keyFactory = KeyFactory.getInstance("RSA");
      privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
      cipher = Cipher.getInstance("RSA");
      cipher.init(Cipher.DECRYPT_MODE, privateKey);
      result = cipher.doFinal(result);
      System.out.println("公鑰加密、私鑰解密——解密：" + new String(result));
    } catch (Exception e) {
      e.printStackTrace();
    }
  }
}

四實現效果

Public Key : MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBAJcBeOb97IdkkirBmx3MOY5e4eRwh0uvC2BcNlY1rDo0lZ8ibR1bl1RJXWkHv7U0ASO/5DBlnnnGbQRtsJlsCPMCAwEAAQ==
Private Key : MIIBVAIBADANBgkqhkiG9w0BAQEFAASCAT4wggE6AgEAAkEAlwF45v3sh2SSKsGbHcw5jl7h5HCHS68LYFw2VjWsOjSVnyJtHVuXVEldaQe/tTQBI7/kMGWeecZtBG2wmWwI8wIDAQABAkAdSkPRSl+ew3s2n+cemIZxfyYB0XHs1D84qapAfpixkUNvWL0A4ovrwsnwt4MEjAtWVTufNvTxIZcZdx+Q5DbBAiEA9TzzYMGRU+3mdlAx0ICF+NIqwvlqyvedKa4KSx55gVUCIQCdoeX6mqGRP78aQjYKWeogwliszjU5fN/LFvKZrcgBJwIhAMvbBLzzaykHY0IKW75kd/lkSyOUTY+20bAp+miDRqGZAiA6r36eeRkzqUbtcL8LxYPb5F79HtxD5dCvnIB/ZGp0uwIgWtXI7IxHjYCsNomSJdu1J3dU9KqQuW/eOHxrk/OgUYE=
私鑰加密、公鑰解密——加密 : VjkFsOiVeLvKES5RprhsJK9tdTzohdELLS7yluidCYEe7DkuCM9srj8kwadynHI4M0oLAfJhK6447hp7Ia8x7A==
私鑰加密、公鑰解密——解密：cakin24 security rsa
公鑰加密、私鑰解密——加密 : gAWl73UxHtO+EfKkpmfMdhtK0Vh7HB8n+30l1Hp8aAMIagD21h2x/q/Ns+soGsOXNovuNzaSGZenmZzcjB4VEA==
公鑰加密、私鑰解密——解密：cakin24 security rsa

五應用場景