java 中DH的方式实现非对称加密的实例

java 中DH的方式实现非对称加密的实例

实现代码：

package com.sahadev;

import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.spec.X509EncodedKeySpec;
import java.util.Objects;

import javax.crypto.Cipher;
import javax.crypto.KeyAgreement;
import javax.crypto.SecretKey;
import javax.crypto.interfaces.DHPublicKey;
import javax.crypto.spec.DHParameterSpec;

import org.apache.commons.codec.binary.Hex;

public class DH {

  public static String src = "Hello,sahadev!";

  public static void main(String[] args) {
    JDKDH();
  }

  public static void JDKDH() {
    try {
      // 初始化发送方密钥
      KeyPairGenerator senderKeyPairGenerator = KeyPairGenerator.getInstance("DH");
      senderKeyPairGenerator.initialize(512);
      KeyPair senderKeyPair = senderKeyPairGenerator.generateKeyPair();
      byte[] senderPublicKey = senderKeyPair.getPublic().getEncoded();

      // 初始化接收方的密钥
      KeyFactory instance = KeyFactory.getInstance("DH");
      X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(senderPublicKey);
      PublicKey sendPublicKeyTemp = instance.generatePublic(x509EncodedKeySpec);
      DHParameterSpec dhParameterSpec = ((DHPublicKey) sendPublicKeyTemp).getParams();
      KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("DH");
      keyPairGenerator.initialize(dhParameterSpec);
      // 接收方生成密钥
      KeyPair generateKeyPair = keyPairGenerator.generateKeyPair();
      byte[] receiverPublicKey = generateKeyPair.getPublic().getEncoded();
      PrivateKey receiverPrivateKey = generateKeyPair.getPrivate();

      // 接收方密钥构建
      KeyAgreement receiverKeyAgreement = KeyAgreement.getInstance("DH");
      receiverKeyAgreement.init(receiverPrivateKey);
      receiverKeyAgreement.doPhase(senderKeyPair.getPublic(), true);
      // 使用我的密钥和你的公钥生成密钥
      SecretKey receiverDesKey = receiverKeyAgreement.generateSecret("DES");

      // 发送方密钥构建
      KeyFactory keyFactory = KeyFactory.getInstance("DH");
      X509EncodedKeySpec x509EncodedKeySpec2 = new X509EncodedKeySpec(receiverPublicKey);
      PublicKey receiverPublicKeyTemp = keyFactory.generatePublic(x509EncodedKeySpec2);

      // 发送方拿到接收方返回的公钥做本地密钥
      KeyAgreement senderKeyAgreement = KeyAgreement.getInstance("DH");
      senderKeyAgreement.init(senderKeyPair.getPrivate());
      senderKeyAgreement.doPhase(receiverPublicKeyTemp, true);
      // 使用你的密钥我的公钥进行构建
      SecretKey senderDesKey = senderKeyAgreement.generateSecret("DES");

      // 判断双方的本地密钥是否相同
      if (Objects.equals(receiverDesKey, senderDesKey)) {
        System.out.println("双方密钥相同");
      }

      // 加密
      Cipher cipher = Cipher.getInstance("DES");
      cipher.init(Cipher.ENCRYPT_MODE, senderDesKey);
      byte[] result = cipher.doFinal(src.getBytes());
      System.out.println("加密结果为 : " + Hex.encodeHexString(result));

      // 解密
      cipher.init(Cipher.DECRYPT_MODE, senderDesKey);
      result = cipher.doFinal(result);
      System.out.println("解密结果为 : " + new String(result));
    } catch (Exception e) {
      e.printStackTrace();
    }

  }

}

附上结果： 

双方密钥相同
DES : da1cc13d388423e82a110539414b1ec0
解密结果为 : Hello,sahadev! 

以上就是DH实现非对称加密的实例，如有 疑问请留言或者到本站社区交流讨论，感谢阅读，希望能帮助到大家，谢谢大家对本站的支持！