Java实现微信小程序加密数据解密算法

程序员文章站 2022-03-04 17:20:21

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一.概述

　　微信推出了小程序，很多公司的客户端应用不仅具有了APP、H5、还接入了小程序开发。但是，小程序中竟然没有提供Java版本的加密数据解密算法。

　　微信小程序提供的加密数据解密算法链接为：https://mp.weixin.qq.com/debug/wxadoc/dev/api/signature.html

　　我们下载的算法示例如下：

Java实现微信小程序加密数据解密算法

博客分类： java基础 java微信小程序AES
　　真的没有java实现示例。

二.实现Java版本的微信小程序加密数据解密算法

1.创建项目

　　这里，我们创建一个Maven工程，具体创建步骤略。

2.配置pom.xml

　　我们在pom.xml中加入如下配置，其中bcprov-jdk15on是为了支持AES的BouncyCastleProvider，而commons-codec则是为了顺利的对session_key,iv,encryptData进行Base64的编解码。

<dependency>
    <groupId>org.bouncycastle</groupId>
    <artifactId>bcprov-jdk16</artifactId>
    <version>1.46</version>
</dependency>

<dependency>
  	<groupId>commons-codec</groupId>
  	<artifactId>commons-codec</artifactId>
  	<version>1.10</version>
</dependency>

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.29</version>
</dependency>

3.实现AES类

package com.bijian.test;

import java.security.AlgorithmParameters;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.Key;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.Security;
 
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
 
/**
 * AES加密
 */
public class AES {
	
	public static boolean initialized = false;
 
	/**
	 * AES解密
	 * 
	 * @param content
	 *            密文
	 * @return
	 * @throws InvalidAlgorithmParameterException
	 * @throws NoSuchProviderException
	 */
	public byte[] decrypt(byte[] content, byte[] keyByte, byte[] ivByte) throws InvalidAlgorithmParameterException {
		initialize();
		try {
			Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
			Key sKeySpec = new SecretKeySpec(keyByte, "AES");
			cipher.init(Cipher.DECRYPT_MODE, sKeySpec, generateIV(ivByte));// 初始化
			byte[] result = cipher.doFinal(content);
			return result;
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		} catch (NoSuchPaddingException e) {
			e.printStackTrace();
		} catch (InvalidKeyException e) {
			e.printStackTrace();
		} catch (IllegalBlockSizeException e) {
			e.printStackTrace();
		} catch (BadPaddingException e) {
			e.printStackTrace();
		} catch (NoSuchProviderException e) {
			e.printStackTrace();
		} catch (Exception e) {
			e.printStackTrace();
		}
		return null;
	}
 
	public static void initialize() {
		if (initialized)
			return;
		Security.addProvider(new BouncyCastleProvider());
		initialized = true;
	}
 
	// 生成iv
	public static AlgorithmParameters generateIV(byte[] iv) throws Exception {
		AlgorithmParameters params = AlgorithmParameters.getInstance("AES");
		params.init(new IvParameterSpec(iv));
		return params;
	}
}

4.实现WxPKCS7Encoder类

package com.bijian.test;

import java.nio.charset.Charset;
import java.util.Arrays;

/**
 * 微信小程序加解密
 */
public class WxPKCS7Encoder {
	private static final Charset CHARSET = Charset.forName("utf-8");
	private static final int BLOCK_SIZE = 32;
 
	/**
	 * 获得对明文进行补位填充的字节.
	 *
	 * @param count
	 *            需要进行填充补位操作的明文字节个数
	 * @return 补齐用的字节数组
	 */
	public static byte[] encode(int count) {
		// 计算需要填充的位数
		int amountToPad = BLOCK_SIZE - (count % BLOCK_SIZE);
		if (amountToPad == 0) {
			amountToPad = BLOCK_SIZE;
		}
		// 获得补位所用的字符
		char padChr = chr(amountToPad);
		String tmp = new String();
		for (int index = 0; index < amountToPad; index++) {
			tmp += padChr;
		}
		return tmp.getBytes(CHARSET);
	}
 
	/**
	 * 删除解密后明文的补位字符
	 *
	 * @param decrypted
	 *            解密后的明文
	 * @return 删除补位字符后的明文
	 */
	public static byte[] decode(byte[] decrypted) {
		int pad = decrypted[decrypted.length - 1];
		if (pad < 1 || pad > 32) {
			pad = 0;
		}
		return Arrays.copyOfRange(decrypted, 0, decrypted.length - pad);
	}
 
	/**
	 * 将数字转化成ASCII码对应的字符，用于对明文进行补码
	 *
	 * @param a
	 *            需要转化的数字
	 * @return 转化得到的字符
	 */
	public static char chr(int a) {
		byte target = (byte) (a & 0xFF);
		return (char) target;
	}
}

5.实现WXCore类

package com.bijian.test;

import org.apache.commons.codec.binary.Base64;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;

/**
 * 封装对外访问方法
 */
public class WXCore {

	private static final String WATERMARK = "watermark";
	private static final String APPID = "appid";

	/**
	 * 解密数据
	 * 
	 * @return
	 * @throws Exception
	 */
	public static String decrypt(String appId, String encryptedData,
			String sessionKey, String iv) {
		String result = "";
		try {
			AES aes = new AES();
			byte[] resultByte = aes.decrypt(Base64.decodeBase64(encryptedData), Base64.decodeBase64(sessionKey), Base64.decodeBase64(iv));
			if (null != resultByte && resultByte.length > 0) {
				result = new String(WxPKCS7Encoder.decode(resultByte));
				JSONObject jsonObject = JSON.parseObject(result);
				String decryptAppid = jsonObject.getJSONObject(WATERMARK)
						.getString(APPID);
				if (!appId.equals(decryptAppid)) {
					result = "";
				}
			}
		} catch (Exception e) {
			result = "";
			e.printStackTrace();
		}
		return result;
	}

	public static void main(String[] args) throws Exception {

		String appId = "wx4f4bc4dec97d474b";
		String encryptedData = "CiyLU1Aw2KjvrjMdj8YKliAjtP4gsMZMQmRzooG2xrDcvSnxIMXFufNstNGTyaGS9uT5geRa0W4oTOb1WT7fJlAC+oNPdbB+3hVbJSRgv+4lGOETKUQz6OYStslQ142dNCuabNPGBzlooOmB231qMM85d2/fV6ChevvXvQP8Hkue1poOFtnEtpyxVLW1zAo6/1Xx1COxFvrc2d7UL/lmHInNlxuacJXwu0fjpXfz/YqYzBIBzD6WUfTIF9GRHpOn/Hz7saL8xz+W//FRAUid1OksQaQx4CMs8LOddcQhULW4ucetDf96JcR3g0gfRK4PC7E/r7Z6xNrXd2UIeorGj5Ef7b1pJAYB6Y5anaHqZ9J6nKEBvB4DnNLIVWSgARns/8wR2SiRS7MNACwTyrGvt9ts8p12PKFdlqYTopNHR1Vf7XjfhQlVsAJdNiKdYmYVoKlaRv85IfVunYzO0IKXsyl7JCUjCpoG20f0a04COwfneQAGGwd5oa+T8yO5hzuyDb/XcxxmK01EpqOyuxINew==";
		String sessionKey = "tiihtNczf5v6AKRyjwEUhQ==";
		String iv = "r7BXXKkLb8qrSNn05n0qiA==";
		System.out.println(decrypt(appId, encryptedData, sessionKey, iv));
	}
}

　　这个类主要是对具体算法的封装，统一对外提供方法。

三.测试

1.运行Java版微信小程序加密数据解密算法

　　这里我就直接运行WXcore类的main方法，这里的测试数据都是从Node.js版微信小程序加密数据解密算法的示例程序中提出来的。我们的运行结果如下：

{"openId":"oGZUI0egBJY1zhBYw2KhdUfwVJJE","nickName":"Band","gender":1,"language":"zh_CN","city":"Guangzhou","province":"Guangdong","country":"CN","avatarUrl":"http://wx.qlogo.cn/mmopen/vi_32/aSKcBBPpibyKNicHNTMM0qJVh8Kjgiak2AHWr8MHM4WgMEm7GFhsf8OYrySdbvAMvTsw3mo8ibKicsnfN5pRjl1p8HQ/0","unionId":"ocMvos6NjeKLIBqg5Mr9QjxrP1FA","watermark":{"timestamp":1477314187,"appid":"wx4f4bc4dec97d474b"}}

2.运行Node.js版微信小程序加密数据解密算法

　　我在Node.js环境中直接运行微信官方提供的Node.js版小程序加密数据解密算法，结果如下：

Java实现微信小程序加密数据解密算法

博客分类： java基础 java微信小程序AES
　　通过对比以上结果可知，我们自行使用Java实现的Java版微信小程序加密数据解密算法与微信官方提供的Node.js版小程序加密数据解密算法结果一致。

四.javax.crypto.Cipher实现

package com.bijian.test;

import org.apache.commons.codec.binary.Base64;
import org.bouncycastle.jce.provider.BouncyCastleProvider;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;

import javax.crypto.*;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

import java.security.*;

public class Test {
	
	private static final String WATERMARK = "watermark";
	private static final String APPID = "appid";
	
	private static boolean hasInited = false;

    public static void init() {
        if (hasInited) {
            return;
        }
        Security.addProvider(new BouncyCastleProvider());
        hasInited = true;
    }

    public static String decrypt(String session_key, String iv, String encryptData) {
    	
        String decryptString = "";
        init();
        byte[] sessionKeyByte = Base64.decodeBase64(session_key);
        byte[] ivByte = Base64.decodeBase64(iv);
        byte[] encryptDataByte = Base64.decodeBase64(encryptData);
        try {
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
            Key key = new SecretKeySpec(sessionKeyByte, "AES");
            AlgorithmParameters algorithmParameters = AlgorithmParameters.getInstance("AES");
            algorithmParameters.init(new IvParameterSpec(ivByte));
            cipher.init(Cipher.DECRYPT_MODE, key, algorithmParameters);
            byte[] bytes = cipher.doFinal(encryptDataByte);
            decryptString = new String(bytes);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return decryptString;
    }
    
    public static void main(String[] args) {
    	String appId = "wx4f4bc4dec97d474b";
        String session_key = "tiihtNczf5v6AKRyjwEUhQ==";
        String iv = "r7BXXKkLb8qrSNn05n0qiA==";
        String encryptData = 
        		"CiyLU1Aw2KjvrjMdj8YKliAjtP4gsMZM"+
        		"QmRzooG2xrDcvSnxIMXFufNstNGTyaGS"+
        		"9uT5geRa0W4oTOb1WT7fJlAC+oNPdbB+"+
        		"3hVbJSRgv+4lGOETKUQz6OYStslQ142d"+
        		"NCuabNPGBzlooOmB231qMM85d2/fV6Ch"+
        		"evvXvQP8Hkue1poOFtnEtpyxVLW1zAo6"+
        		"/1Xx1COxFvrc2d7UL/lmHInNlxuacJXw"+
        		"u0fjpXfz/YqYzBIBzD6WUfTIF9GRHpOn"+
        		"/Hz7saL8xz+W//FRAUid1OksQaQx4CMs"+
        		"8LOddcQhULW4ucetDf96JcR3g0gfRK4P"+
        		"C7E/r7Z6xNrXd2UIeorGj5Ef7b1pJAYB"+
        		"6Y5anaHqZ9J6nKEBvB4DnNLIVWSgARns"+
        		"/8wR2SiRS7MNACwTyrGvt9ts8p12PKFd"+
        		"lqYTopNHR1Vf7XjfhQlVsAJdNiKdYmYV"+
        		"oKlaRv85IfVunYzO0IKXsyl7JCUjCpoG"+
        		"20f0a04COwfneQAGGwd5oa+T8yO5hzuy"+
        		"Db/XcxxmK01EpqOyuxINew==";
        String decrypt = decrypt(session_key, iv, encryptData);
        JSONObject jsonObject = JSON.parseObject(decrypt);
    	String decryptAppid = jsonObject.getJSONObject(WATERMARK).getString(APPID);
    	if(!appId.equals(decryptAppid)){
    		decrypt = "";
    	}
        System.out.println(decrypt);
    }
}

　　运行结果和上面的运行结果是一致的。

附：

jar包下载地址：http://mvnrepository.com/artifact/org.bouncycastle/bcprov-jdk16/1.46

文章来源：

https://blog.csdn.net/l1028386804/article/details/79450115

https://blog.csdn.net/u013187628/article/details/80665574