大家好，我是雄雄，欢迎你的到来。

前言：

最近一直在搞微信服务（公众）号开发，前面也写过一篇文章，是关于一开始配置、验证token以及接收用户触发关注/取消关注事件时的接口，文章地址：java实现微信服务（公众）号用户关注时，获取openid，安全模式下的加密解密实现

今天将加密解密的工具类汇总整理一下发出来，记录一下。

加密/解密工具类

/*** 对公众平台发送给公众账号的消息加解密示例代码.* * @copyright Copyright (c) 1998-2014 Tencent Inc.*/// ------------------------------------------------------------------------/*** 针对org.apache.commons.codec.binary.Base64，* 需要导入架包commons-codec-1.9（或commons-codec-1.8等其他版本）* 官方下载地址：http://commons.apache.org/proper/commons-codec/download_codec.cgi*/
package org.jeecg.modules.utils;import java.nio.charset.Charset;
import java.util.Arrays;
import java.util.Random;import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;import org.apache.commons.codec.binary.Base64;/*** 提供接收和推送给公众平台消息的加解密接口(UTF8编码的字符串).* <ol>* 	<li>第三方回复加密消息给公众平台</li>* 	<li>第三方收到公众平台发送的消息，验证消息的安全性，并对消息进行解密。</li>* </ol>* 说明：异常java.security.InvalidKeyException:illegal Key Size的解决方案* <ol>* 	<li>在官方网站下载JCE无限制权限策略文件（JDK7的下载地址：*      http://www.oracle.com/technetwork/java/javase/downloads/jce-7-download-432124.html</li>* 	<li>下载后解压，可以看到local_policy.jar和US_export_policy.jar以及readme.txt</li>* 	<li>如果安装了JRE，将两个jar文件放到%JRE_HOME%\lib\security目录下覆盖原来的文件</li>* 	<li>如果安装了JDK，将两个jar文件放到%JDK_HOME%\jre\lib\security目录下覆盖原来文件</li>* </ol>*/
public class WXBizMsgCrypt {static Charset CHARSET = Charset.forName("utf-8");Base64 base64 = new Base64();byte[] aesKey;String token;String appId;/*** 构造函数* @param token 公众平台上，开发者设置的token* @param encodingAesKey 公众平台上，开发者设置的EncodingAESKey* @param appId 公众平台appid* * @throws AesException 执行失败，请查看该异常的错误码和具体的错误信息*/public WXBizMsgCrypt(String token, String encodingAesKey, String appId) throws AesException {if (encodingAesKey.length() != 43) {throw new AesException(AesException.IllegalAesKey);}this.token = token;this.appId = appId;aesKey = Base64.decodeBase64(encodingAesKey + "=");}// 生成4个字节的网络字节序byte[] getNetworkBytesOrder(int sourceNumber) {byte[] orderBytes = new byte[4];orderBytes[3] = (byte) (sourceNumber & 0xFF);orderBytes[2] = (byte) (sourceNumber >> 8 & 0xFF);orderBytes[1] = (byte) (sourceNumber >> 16 & 0xFF);orderBytes[0] = (byte) (sourceNumber >> 24 & 0xFF);return orderBytes;}// 还原4个字节的网络字节序int recoverNetworkBytesOrder(byte[] orderBytes) {int sourceNumber = 0;for (int i = 0; i < 4; i++) {sourceNumber <<= 8;sourceNumber |= orderBytes[i] & 0xff;}return sourceNumber;}// 随机生成16位字符串String getRandomStr() {String base = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";Random random = new Random();StringBuffer sb = new StringBuffer();for (int i = 0; i < 16; i++) {int number = random.nextInt(base.length());sb.append(base.charAt(number));}return sb.toString();}/*** 对明文进行加密.* * @param text 需要加密的明文* @return 加密后base64编码的字符串* @throws AesException aes加密失败*/String encrypt(String randomStr, String text) throws AesException {ByteGroup byteCollector = new ByteGroup();byte[] randomStrBytes = randomStr.getBytes(CHARSET);byte[] textBytes = text.getBytes(CHARSET);byte[] networkBytesOrder = getNetworkBytesOrder(textBytes.length);byte[] appidBytes = appId.getBytes(CHARSET);// randomStr + networkBytesOrder + text + appidbyteCollector.addBytes(randomStrBytes);byteCollector.addBytes(networkBytesOrder);byteCollector.addBytes(textBytes);byteCollector.addBytes(appidBytes);// ... + pad: 使用自定义的填充方式对明文进行补位填充byte[] padBytes = PKCS7Encoder.encode(byteCollector.size());byteCollector.addBytes(padBytes);// 获得最终的字节流, 未加密byte[] unencrypted = byteCollector.toBytes();try {// 设置加密模式为AES的CBC模式Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");SecretKeySpec keySpec = new SecretKeySpec(aesKey, "AES");IvParameterSpec iv = new IvParameterSpec(aesKey, 0, 16);cipher.init(Cipher.ENCRYPT_MODE, keySpec, iv);// 加密byte[] encrypted = cipher.doFinal(unencrypted);// 使用BASE64对加密后的字符串进行编码String base64Encrypted = base64.encodeToString(encrypted);return base64Encrypted;} catch (Exception e) {e.printStackTrace();throw new AesException(AesException.EncryptAESError);}}/*** 对密文进行解密.* * @param text 需要解密的密文* @return 解密得到的明文* @throws AesException aes解密失败*/String decrypt(String text) throws AesException {byte[] original;try {// 设置解密模式为AES的CBC模式Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");SecretKeySpec key_spec = new SecretKeySpec(aesKey, "AES");IvParameterSpec iv = new IvParameterSpec(Arrays.copyOfRange(aesKey, 0, 16));cipher.init(Cipher.DECRYPT_MODE, key_spec, iv);// 使用BASE64对密文进行解码byte[] encrypted = Base64.decodeBase64(text);// 解密original = cipher.doFinal(encrypted);} catch (Exception e) {e.printStackTrace();throw new AesException(AesException.DecryptAESError);}String xmlContent, from_appid;try {// 去除补位字符byte[] bytes = PKCS7Encoder.decode(original);// 分离16位随机字符串,网络字节序和AppIdbyte[] networkOrder = Arrays.copyOfRange(bytes, 16, 20);int xmlLength = recoverNetworkBytesOrder(networkOrder);xmlContent = new String(Arrays.copyOfRange(bytes, 20, 20 + xmlLength), CHARSET);from_appid = new String(Arrays.copyOfRange(bytes, 20 + xmlLength, bytes.length),CHARSET);} catch (Exception e) {e.printStackTrace();throw new AesException(AesException.IllegalBuffer);}// appid不相同的情况if (!from_appid.equals(appId)) {throw new AesException(AesException.ValidateAppidError);}return xmlContent;}/*** 将公众平台回复用户的消息加密打包.* <ol>* 	<li>对要发送的消息进行AES-CBC加密</li>* 	<li>生成安全签名</li>* 	<li>将消息密文和安全签名打包成xml格式</li>* </ol>* * @param replyMsg 公众平台待回复用户的消息，xml格式的字符串* @param timeStamp 时间戳，可以自己生成，也可以用URL参数的timestamp* @param nonce 随机串，可以自己生成，也可以用URL参数的nonce* * @return 加密后的可以直接回复用户的密文，包括msg_signature, timestamp, nonce, encrypt的xml格式的字符串* @throws AesException 执行失败，请查看该异常的错误码和具体的错误信息*/public String encryptMsg(String replyMsg, String timeStamp, String nonce) throws AesException {// 加密String encrypt = encrypt(getRandomStr(), replyMsg);// 生成安全签名if (timeStamp == "") {timeStamp = Long.toString(System.currentTimeMillis());}String signature = SHA1.getSHA1(token, timeStamp, nonce, encrypt);// System.out.println("发送给平台的签名是: " + signature[1].toString());// 生成发送的xmlString result = XMLParse.generate(encrypt, signature, timeStamp, nonce);return result;}/*** 检验消息的真实性，并且获取解密后的明文.* <ol>* 	<li>利用收到的密文生成安全签名，进行签名验证</li>* 	<li>若验证通过，则提取xml中的加密消息</li>* 	<li>对消息进行解密</li>* </ol>* * @param msgSignature 签名串，对应URL参数的msg_signature* @param timeStamp 时间戳，对应URL参数的timestamp* @param nonce 随机串，对应URL参数的nonce* @param postData 密文，对应POST请求的数据* * @return 解密后的原文* @throws AesException 执行失败，请查看该异常的错误码和具体的错误信息*/public String decryptMsg(String msgSignature, String timeStamp, String nonce, String postData)throws AesException {// 密钥，公众账号的app secret// 提取密文Object[] encrypt = XMLParse.extract(postData);// 验证安全签名String signature = SHA1.getSHA1(token, timeStamp, nonce, encrypt[1].toString());// 和URL中的签名比较是否相等// System.out.println("第三方收到URL中的签名：" + msg_sign);// System.out.println("第三方校验签名：" + signature);if (!signature.equals(msgSignature)) {throw new AesException(AesException.ValidateSignatureError);}// 解密String result = decrypt(encrypt[1].toString());return result;}/*** 验证URL* @param msgSignature 签名串，对应URL参数的msg_signature* @param timeStamp 时间戳，对应URL参数的timestamp* @param nonce 随机串，对应URL参数的nonce* @param echoStr 随机串，对应URL参数的echostr* * @return 解密之后的echostr* @throws AesException 执行失败，请查看该异常的错误码和具体的错误信息*/public String verifyUrl(String msgSignature, String timeStamp, String nonce, String echoStr)throws AesException {String signature = SHA1.getSHA1(token, timeStamp, nonce, echoStr);if (!signature.equals(msgSignature)) {throw new AesException(AesException.ValidateSignatureError);}String result = decrypt(echoStr);return result;}}

官方提供的测试类：

package org.jeecg.modules.utils;import static org.junit.Assert.*;import java.io.IOException;
import java.io.StringReader;import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;import org.junit.*;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;public class WXBizMsgCryptTest {String encodingAesKey = "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFG";String tokeN = "";String timestamp = "1409304348";String nonce = "xxxxxx";String appId = "wxb11529c136998cb6";String replyMsg = "我是中文abcd123";String xmlFormat = "<xml><><![CDATA[toUser]]></ToUserName><Encrypt><![CDATA[%1$s]]></Encrypt></xml>";String afterAesEncrypt = "jn1L23DB+6ELqJ++3bnyg5K55bgVtVzd832WzZGMhkP72vVOfg==";String randomStr = "aaaabbbbccccdddd";String replyMsg2 = "<xml><ToUserName><![CDATA[oia2Tj我是中文jewbmiOUlr6X-1crbLOvLw]]></ToUserName><FromUserName><![CDATA[gh_7f083739789a]]></FromUserName><CreateTime>1407743423</CreateTime><MsgType><![CDATA[video]]></MsgType><Video><MediaId><![CDATA[eYJ1MbwPRJtOvIEabaxHs7TX2D-HV71s79GUxqdUkjm6Gs2Ed1KF3ulAOA9H1xG0]]></MediaId><Title><![CDATA[testCallBackReplyVideo]]></Title><Description><![CDATA[testCallBackReplyVideo]]></Description></Video></xml>";String afterAesEncrypt2 = "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";@BeforeClasspublic static void setUpBeforeClass() throws Exception {}@AfterClasspublic static void tearDownAfterClass() throws Exception {}@Beforepublic void setUp() throws Exception {}@Afterpublic void tearDown() throws Exception {}@Testpublic void testNormal() throws ParserConfigurationException, SAXException, IOException {try {WXBizMsgCrypt pc = new WXBizMsgCrypt(token, encodingAesKey, appId);String afterEncrpt = pc.encryptMsg(replyMsg, timestamp, nonce);DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();DocumentBuilder db = dbf.newDocumentBuilder();StringReader sr = new StringReader(afterEncrpt);InputSource is = new InputSource(sr);Document document = db.parse(is);Element root = document.getDocumentElement();NodeList nodelist1 = root.getElementsByTagName("Encrypt");NodeList nodelist2 = root.getElementsByTagName("MsgSignature");String encrypt = nodelist1.item(0).getTextContent();String msgSignature = nodelist2.item(0).getTextContent();String fromXML = String.format(xmlFormat, encrypt);// 第三方收到公众号平台发送的消息String afterDecrpt = pc.decryptMsg(msgSignature, timestamp, nonce, fromXML);assertEquals(replyMsg, afterDecrpt);} catch (AesException e) {fail("正常流程，怎么就抛出异常了？？？？？？");}}@Testpublic void testAesEncrypt() {try {WXBizMsgCrypt pc = new WXBizMsgCrypt(token, encodingAesKey, appId);assertEquals(afterAesEncrypt, pc.encrypt(randomStr, replyMsg));} catch (AesException e) {e.printStackTrace();fail("no异常");}}@Testpublic void testAesEncrypt2() {try {WXBizMsgCrypt pc = new WXBizMsgCrypt(token, encodingAesKey, appId);assertEquals(afterAesEncrypt2, pc.encrypt(randomStr, replyMsg2));} catch (AesException e) {e.printStackTrace();fail("no异常");}}@Testpublic void testIllegalAesKey() {try {new WXBizMsgCrypt(token, "abcde", appId);} catch (AesException e) {assertEquals(AesException.IllegalAesKey, e.getCode());return;}fail("错误流程不抛出异常？？？");}@Testpublic void testValidateSignatureError() throws ParserConfigurationException, SAXException,IOException {try {WXBizMsgCrypt pc = new WXBizMsgCrypt(token, encodingAesKey, appId);String afterEncrpt = pc.encryptMsg(replyMsg, timestamp, nonce);DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();DocumentBuilder db = dbf.newDocumentBuilder();StringReader sr = new StringReader(afterEncrpt);InputSource is = new InputSource(sr);Document document = db.parse(is);Element root = document.getDocumentElement();NodeList nodelist1 = root.getElementsByTagName("Encrypt");String encrypt = nodelist1.item(0).getTextContent();String fromXML = String.format(xmlFormat, encrypt);pc.decryptMsg("12345", timestamp, nonce, fromXML); // 这里签名错误} catch (AesException e) {assertEquals(AesException.ValidateSignatureError, e.getCode());return;}fail("错误流程不抛出异常？？？");}@Testpublic void testVerifyUrl() throws AesException {WXBizMsgCrypt wxcpt = new WXBizMsgCrypt("QDG6eK","jWmYm7qr5nMoAUwZRjGtBxmz3KA1tkAj3ykkR6q2B2C", "wx5823bf96d3bd56c7");String verifyMsgSig = "5c45ff5e21c57e6ad56bac8758b79b1d9ac89fd3";String timeStamp = "1409659589";String nonce = "263014780";String echoStr = "P9nAzCzyDtyTWESHep1vC5X9xho/qYX3Zpb4yKa9SKld1DsH3Iyt3tP3zNdtp+4RPcs8TgAE7OaBO+FZXvnaqQ==";wxcpt.verifyUrl(verifyMsgSig, timeStamp, nonce, echoStr);// 只要不抛出异常就好}
}

我的解密测试

这个是我写的解密测试类，其实也差不多，只是我为了后面维护方便，将共用的信息提取到了常量类中：

package org.jeecg.modules.utils;import org.jeecg.modules.config.WeChatContant;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import java.io.StringReader;/*** @author: muxiongxiong* @date: 2022年08月17日 下午 9:21* 公众号：雄雄的小课堂* 博客：https://blog.csdn.net/qq_34137397* 个人站：http://www.穆雄雄.com* 个人站：http://www.muxiongxiong.cn* @Description: 官方提供的加解密demo类*/
public class Program {// 需要加密的明文String encodingAesKey = WeChatContant.ENCODINGAESKEY;String token = WeChatContant.TOKEN;String timestamp = "1409304348";String nonce = "xxxxxx";String appId = WeChatContant.APPID;/*** main方法* @param args* @throws Exception*/public static void main(String[] args) throws Exception {Program program = new Program();program.decode();}/*** 解密测试*/public  void decode() throws AesException {//构造函数WXBizMsgCrypt pc = new WXBizMsgCrypt(token, encodingAesKey, appId);String miwen = "5Fhy9chrfcshHmeCrAKLBZmJdYWm1RwDNYOyCfbVC6L1MUAUto5xOimdotgLBSCKRyt+yys+o+5aO0nRdO4XfS9CAhYK50NeO6O/M8woX0fanUn/DjYGJV4Mm/Zfg7KmpkXXxwguo5RJrYweglVOHZ96tLWZppAA5/LDl26YF2TmaBWAwPZU1n8R1Wg8jCaSolXBOYZ90lE3854n/+GV27xtpNy1+a+lPs5YPmyauL6wCCU2g2H71g4iYyz4ifi1afxmZsI6vkmKv0sncQMfkOYgX7g0pOZaQ/rnwjmnGfFpmY3DJe7ufmSyd+LA/5r93PIW0vW7j/Bf7xbw77ElrSghvA/Ro6U+xEZHNF3ZUqb5ce1P+62qPakC0r23RlJfMhTVF1yqKL0W/fM1pNbCfJC7KBX9IHja9bxPuN7QiWs=";String jiemi = pc.decrypt(miwen);System.out.println("解密后的内容是："+jiemi);}/*** 官方提供的示例代码* @throws Exception*/public  void authorityDemo() throws Exception{String replyMsg = " 中文<xml><ToUserName><![CDATA[oia2TjjewbmiOUlr6X-1crbLOvLw]]></ToUserName><FromUserName><![CDATA[gh_7f083739789a]]></FromUserName><CreateTime>1407743423</CreateTime><MsgType><![CDATA[video]]></MsgType><Video><MediaId><![CDATA[eYJ1MbwPRJtOvIEabaxHs7TX2D-HV71s79GUxqdUkjm6Gs2Ed1KF3ulAOA9H1xG0]]></MediaId><Title><![CDATA[testCallBackReplyVideo]]></Title><Description><![CDATA[testCallBackReplyVideo]]></Description></Video></xml>";//构造函数WXBizMsgCrypt pc = new WXBizMsgCrypt(token, encodingAesKey, appId);String mingwen = pc.encryptMsg(replyMsg, timestamp, nonce);System.out.println("加密后: " + mingwen);DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();dbf.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);dbf.setFeature("http://xml.org/sax/features/external-general-entities", false);dbf.setFeature("http://xml.org/sax/features/external-parameter-entities", false);dbf.setFeature("http://apache.org/xml/features/nonvalidating/load-external-dtd", false);dbf.setXIncludeAware(false);dbf.setExpandEntityReferences(false);DocumentBuilder db = dbf.newDocumentBuilder();StringReader sr = new StringReader(mingwen);InputSource is = new InputSource(sr);Document document = db.parse(is);Element root = document.getDocumentElement();NodeList nodelist1 = root.getElementsByTagName("Encrypt");NodeList nodelist2 = root.getElementsByTagName("MsgSignature");String encrypt = nodelist1.item(0).getTextContent();String msgSignature = nodelist2.item(0).getTextContent();String format = "<xml><ToUserName><![CDATA[toUser]]></ToUserName><Encrypt><![CDATA[%1$s]]></Encrypt></xml>";String fromXML = String.format(format, encrypt);//// 公众平台发送消息给第三方，第三方处理//// 第三方收到公众号平台发送的消息String result2 = pc.decryptMsg(msgSignature, timestamp, nonce, fromXML);System.out.println("解密后明文: " + result2);//pc.verifyUrl(null, null, null, null);}}

然后就可以了。