以DH的方式实现非对称加密-阿里云开发者社区

开发者社区> 安全> 正文
登录阅读全文

以DH的方式实现非对称加密

简介: package com.sahadev; import java.security.KeyFactory; import java.security.KeyPair; import java.
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!


版权声明:本文内容由阿里云实名注册用户自发贡献,版权归原作者所有,阿里云开发者社区不拥有其著作权,亦不承担相应法律责任。具体规则请查看《阿里云开发者社区用户服务协议》和《阿里云开发者社区知识产权保护指引》。如果您发现本社区中有涉嫌抄袭的内容,填写侵权投诉表单进行举报,一经查实,本社区将立刻删除涉嫌侵权内容。

分享:
+ 订阅

云安全开发者的大本营

其他文章