企业微信开启接收消息+验证URL有效性-CSDN博客

简介

前期准备

• 一个备案的域名。
• 可线上部署的应用与域名对应。

2.3使用到的示例代码来源企业微信-开发者中心

• 访问地址

  https://developer.work.weixin.qq.com/document/path/90468
  

• 示例代码下载链接

  https://open.work.weixin.qq.com/wwopen/downloadfile/java.zip
  

关于企业微信的开启接收信息的文档

https://developer.work.weixin.qq.com/document/10514

本文关键词

企业微信开启接收消息、验证URL有效性、SHA1、提供接收和推送给企业微信消息的加解密接口、计算消息签名接口

实现步骤

1 开启接收消息

1.1 设置接收消息的参数

在企业的管理端后台进入需要设置接收消息的目标应用点击“接收消息”的“设置API接收”按钮进入配置页面。

用的URL、Token、EncodingAESKey三个参数

• URL是企业后台接收企业微信推送请求的访问协议和地址支持http或https协议。
• Token可由企业任意填写用于生成签名。
• EncodingAESKey用于消息体的加密是AES密钥的Base64编码。

这三个参数需要在下面代码中使用到。

2 验证URL有效性

2.1 官方说明

当点击“保存”提交以上信息时企业微信会发送一条验证消息到填写的URL发送方法为GET。
企业的接收消息服务器接收到验证请求后需要作出正确的响应才能通过URL验证。

假设接收消息地址设置为http://api.3dept.com/企业微信将向该地址发送如下验证请求

请求方式GET
请求地址

http://api.3dept.com/?msg_signature=ASDFQWEXZCVAQFASDFASDFSS&timestamp=13500001234&nonce=123412323&echostr=ENCRYPT_STR

参数说明

参数	必须	说明
msg_signature	是	企业微信加密签名msg_signature结合了企业填写的token、请求中的timestamp、nonce参数、加密的消息体
timestamp	是	时间戳
nonce	是	随机数
echostr	是	加密的字符串。需要解密得到消息内容明文解密后有random、msg_len、msg、CorpID四个字段其中msg即为消息内容明文

企业后台收到请求后需要做如下操作

1. 对收到的请求做Urldecode处理
2. 通过参数msg_signature对请求进行校验确认调用者的合法性。
3. 解密echostr参数得到消息内容(即msg字段)
4. 在1秒内原样返回明文消息内容(不能加引号不能带bom头不能带换行符)

2.2 Java代码

控制器层代码QYWeiXinLoginController.java

package com.ruoyi.project.controller;


import com.ruoyi.project.tx.qyweixin.service.IQYWeiXinLoginService;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;


@RestController
@RequestMapping("/wechat/info")
public class QYWechatInfoController {

    @Resource
    private IQYWeiXinLoginService qyWeiXinLoginService;

    /**
     * 验证URL有效性
     *
     */
    @RequestMapping(value = "/verifyURLValidity", method = RequestMethod.GET)
    public void verifyURLValidity(@RequestParam(value = "msg_signature", required = true) String msgSignature,
                                  @RequestParam(value = "timestamp", required = true) String timestamp,
                                  @RequestParam(value = "nonce", required = true) String nonce,
                                  @RequestParam(value = "echostr", required = true) String echostr,
                                  HttpServletResponse response) {
        String msg = qyWeiXinLoginService.verifyURLValidity(msgSignature, timestamp, nonce, echostr);
        try {
            response.getWriter().print(msg);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

}

业务接口IQYWeiXinLoginService.java

package com.ruoyi.project.tx.qyweixin.service;


public interface IQYWeiXinLoginService {
    String verifyURLValidity(String msgSignature, String timestamp, String nonce, String echostr);
}

业务接口实现QYWeiXinLoginServiceImpl.java

package com.ruoyi.project.tx.qyweixin.service.impl;


import com.ruoyi.project.tx.qyweixin.service.IQYWeiXinLoginService;
import com.ruoyi.project.utils.aes.AesException;
import com.ruoyi.project.utils.aes.WXBizMsgCrypt;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Service;

@Service
public class QYWeiXinLoginServiceImpl implements IQYWeiXinLoginService {
    private static final Logger logger = LoggerFactory.getLogger(QYWeiXinLoginServiceImpl.class);

    @Override
    public String  verifyURLValidity(String msgSignature, String timestamp, String nonce, String echostr) {
        logger.info("企业微信登录获取到的参数msgSignature:{},timestamp:{},nonce:{},echostr:{}:",msgSignature,timestamp,nonce,echostr);
        //token
        String TOKEN = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";
        // encodingAESKey
        String ENCODINGAES_KEY = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";
        //企业ID
        String CORP_ID = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";

        // 通过检验msg_signature对请求进行校验若校验成功则原样返回echostr表示接入成功否则接入失败
        String result = null;
        try {
            WXBizMsgCrypt wxcpt = new WXBizMsgCrypt(TOKEN, ENCODINGAES_KEY, CORP_ID);
            result = wxcpt.VerifyURL(msgSignature, timestamp, nonce, echostr);
        } catch (AesException e) {
            e.printStackTrace();
        }
        logger.info("----------微信接口访问结束----------");
        return result;
    }
}

2.3 使用到的示例代码

提供接收和推送给企业微信消息的加解密接口WXBizMsgCrypt.java

/**
 * 对企业微信发送给企业后台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 com.ruoyi.project.utils.aes;

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;

/**
 * 提供接收和推送给企业微信消息的加解密接口(UTF8编码的字符串).
 * <ol>
 * 	<li>第三方回复加密消息给企业微信</li>
 * 	<li>第三方收到企业微信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 receiveid;

	/**
	 * 构造函数
	 * @param token 企业微信后台开发者设置的token
	 * @param encodingAesKey 企业微信后台开发者设置的EncodingAESKey
	 * @param receiveid, 不同场景含义不同详见文档
	 *
	 * @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 receiveid) throws AesException {
		if (encodingAesKey.length() != 43) {
			throw new AesException(AesException.IllegalAesKey);
		}

		this.token = token;
		this.receiveid = receiveid;
		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[] receiveidBytes = receiveid.getBytes(CHARSET);

		// randomStr + networkBytesOrder + text + receiveid
		byteCollector.addBytes(randomStrBytes);
		byteCollector.addBytes(networkBytesOrder);
		byteCollector.addBytes(textBytes);
		byteCollector.addBytes(receiveidBytes);

		// ... + 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_receiveid;
		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receiveid
			byte[] networkOrder = Arrays.copyOfRange(bytes, 16, 20);

			int xmlLength = recoverNetworkBytesOrder(networkOrder);

			xmlContent = new String(Arrays.copyOfRange(bytes, 20, 20 + xmlLength), CHARSET);
			from_receiveid = new String(Arrays.copyOfRange(bytes, 20 + xmlLength, bytes.length),
					CHARSET);
		} catch (Exception e) {
			e.printStackTrace();
			throw new AesException(AesException.IllegalBuffer);
		}

		// receiveid不相同的情况
		if (!from_receiveid.equals(receiveid)) {
			throw new AesException(AesException.ValidateCorpidError);
		}
		return xmlContent;

	}

	/**
	 * 将企业微信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 企业微信待回复用户的消息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xml
		String 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;
	}

}

加解密异常类AesException.java

package com.ruoyi.project.utils.aes;

/**
 * 加解密异常类
 */
public class AesException extends Exception {
    public final static int OK = 0;
    public final static int ValidateSignatureError = -40001;
    public final static int ParseXmlError = -40002;
    public final static int ComputeSignatureError = -40003;
    public final static int IllegalAesKey = -40004;
    public final static int ValidateCorpidError = -40005;
    public final static int EncryptAESError = -40006;
    public final static int DecryptAESError = -40007;
    public final static int IllegalBuffer = -40008;
//public final static int EncodeBase64Error = -40009;
//public final static int DecodeBase64Error = -40010;
//public final static int GenReturnXmlError = -40011;
    private int code;

    private static String getMessage(int code) {
        switch (code) {
            case ValidateSignatureError:
                return "签名验证错误";
            case ParseXmlError:
                return "xml解析失败";
            case ComputeSignatureError:
                return "sha加密生成签名失败";
            case IllegalAesKey:
                return "SymmetricKey非法";
            case ValidateCorpidError:
                return "corpid校验失败";
            case EncryptAESError:
                return "aes加密失败";
            case DecryptAESError:
                return "aes解密失败";
            case IllegalBuffer:
                return "解密后得到的buffer非法";
//		case EncodeBase64Error:
//			return "base64加密错误";
//		case DecodeBase64Error:
//			return "base64解密错误";
//		case GenReturnXmlError:
//			return "xml生成失败";
            default:
                return null; // cannot be
        }
    }
    public int getCode() {
        return code;
    }
    AesException(int code) {
        super(getMessage(code));
        this.code = code;
    }
}

ByteGroup.java

package com.ruoyi.project.utils.aes;

import java.util.ArrayList;

class ByteGroup {
	ArrayList<Byte> byteContainer = new ArrayList<Byte>();

	public byte[] toBytes() {
		byte[] bytes = new byte[byteContainer.size()];
		for (int i = 0; i < byteContainer.size(); i++) {
			bytes[i] = byteContainer.get(i);
		}
		return bytes;
	}

	public ByteGroup addBytes(byte[] bytes) {
		for (byte b : bytes) {
			byteContainer.add(b);
		}
		return this;
	}

	public int size() {
		return byteContainer.size();
	}
}

提供基于PKCS7算法的加解密接口PKCS7Encoder.java

package com.ruoyi.project.utils.aes;

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

/**
 * 提供基于PKCS7算法的加解密接口.
 */
class PKCS7Encoder {
	static Charset CHARSET = Charset.forName("utf-8");
	static 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
	 */
	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
	 */
	static byte[] decode(byte[] decrypted) {
		int pad = (int) 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
	 */
	static char chr(int a) {
		byte target = (byte) (a & 0xFF);
		return (char) target;
	}

}

计算消息签名接口SHA1.java

package com.ruoyi.project.utils.aes;

import java.security.MessageDigest;
import java.util.Arrays;
/**
 * 对企业微信发送给企业后台的消息加解密示例代码.
 *
 * @copyright Copyright (c) 1998-2014 Tencent Inc.
 */
/**
 * SHA1 class
 *
 * 计算消息签名接口.
 */
public class SHA1 {

	/**
	 * 用SHA1算法生成安全签名
	 * @param token 票据
	 * @param timestamp 时间戳
	 * @param nonce 随机字符串
	 * @param encrypt 密文
	 * @return 安全签名
	 * @throws AesException
	 */
	public static String getSHA1(String token, String timestamp, String nonce, String encrypt) throws AesException
			  {
		try {
			String[] array = new String[] { token, timestamp, nonce, encrypt };
			StringBuffer sb = new StringBuffer();
			// 字符串排序
			Arrays.sort(array);
			for (int i = 0; i < 4; i++) {
				sb.append(array[i]);
			}
			String str = sb.toString();
			// SHA1签名生成
			MessageDigest md = MessageDigest.getInstance("SHA-1");
			md.update(str.getBytes());
			byte[] digest = md.digest();

			StringBuffer hexstr = new StringBuffer();
			String shaHex = "";
			for (int i = 0; i < digest.length; i++) {
				shaHex = Integer.toHexString(digest[i] & 0xFF);
				if (shaHex.length() < 2) {
					hexstr.append(0);
				}
				hexstr.append(shaHex);
			}
			return hexstr.toString();
		} catch (Exception e) {
			e.printStackTrace();
			throw new AesException(AesException.ComputeSignatureError);
		}
	}
}

提供提取消息格式中的密文及生成回复消息格式的接口XMLParse.java

/**
 * 对企业微信发送给企业后台的消息加解密示例代码.
 *
 * @copyright Copyright (c) 1998-2014 Tencent Inc.
 */

// ------------------------------------------------------------------------

package com.ruoyi.project.utils.aes;

import java.io.StringReader;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;

/**
 * XMLParse class
 *
 * 提供提取消息格式中的密文及生成回复消息格式的接口.
 */
class XMLParse {

	/**
	 * 提取出xml数据包中的加密消息
	 * @param xmltext 待提取的xml字符串
	 * @return 提取出的加密消息字符串
	 * @throws AesException
	 */
	public static Object[] extract(String xmltext) throws AesException     {
		Object[] result = new Object[3];
		try {
			DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();

			String FEATURE = null;
			// This is the PRIMARY defense. If DTDs (doctypes) are disallowed, almost all XML entity attacks are prevented
			// Xerces 2 only - http://xerces.apache.org/xerces2-j/features.html#disallow-doctype-decl
			FEATURE = "http://apache.org/xml/features/disallow-doctype-decl";
			dbf.setFeature(FEATURE, true);

			// If you can't completely disable DTDs, then at least do the following:
			// Xerces 1 - http://xerces.apache.org/xerces-j/features.html#external-general-entities
			// Xerces 2 - http://xerces.apache.org/xerces2-j/features.html#external-general-entities
			// JDK7+ - http://xml.org/sax/features/external-general-entities
			FEATURE = "http://xml.org/sax/features/external-general-entities";
			dbf.setFeature(FEATURE, false);

			// Xerces 1 - http://xerces.apache.org/xerces-j/features.html#external-parameter-entities
			// Xerces 2 - http://xerces.apache.org/xerces2-j/features.html#external-parameter-entities
			// JDK7+ - http://xml.org/sax/features/external-parameter-entities
			FEATURE = "http://xml.org/sax/features/external-parameter-entities";
			dbf.setFeature(FEATURE, false);

			// Disable external DTDs as well
			FEATURE = "http://apache.org/xml/features/nonvalidating/load-external-dtd";
			dbf.setFeature(FEATURE, false);

			// and these as well, per Timothy Morgan's 2014 paper: "XML Schema, DTD, and Entity Attacks"
			dbf.setXIncludeAware(false);
			dbf.setExpandEntityReferences(false);

			// And, per Timothy Morgan: "If for some reason support for inline DOCTYPEs are a requirement, then
			// ensure the entity settings are disabled (as shown above) and beware that SSRF attacks
			// (http://cwe.mitre.org/data/definitions/918.html) and denial
			// of service attacks (such as billion laughs or decompression bombs via "jar:") are a risk."

			// remaining parser logic
			DocumentBuilder db = dbf.newDocumentBuilder();
			StringReader sr = new StringReader(xmltext);
			InputSource is = new InputSource(sr);
			Document document = db.parse(is);

			Element root = document.getDocumentElement();
			NodeList nodelist1 = root.getElementsByTagName("Encrypt");
			result[0] = 0;
			result[1] = nodelist1.item(0).getTextContent();
			return result;
		} catch (Exception e) {
			e.printStackTrace();
			throw new AesException(AesException.ParseXmlError);
		}
	}

	/**
	 * 生成xml消息
	 * @param encrypt 加密后的消息密文
	 * @param signature 安全签名
	 * @param timestamp 时间戳
	 * @param nonce 随机字符串
	 * @return 生成的xml字符串
	 */
	public static String generate(String encrypt, String signature, String timestamp, String nonce) {

		String format = "<xml>\n" + "<Encrypt><![CDATA[%1$s]]></Encrypt>\n"
				+ "<MsgSignature><![CDATA[%2$s]]></MsgSignature>\n"
				+ "<TimeStamp>%3$s</TimeStamp>\n" + "<Nonce><![CDATA[%4$s]]></Nonce>\n" + "</xml>";
		return String.format(format, encrypt, signature, timestamp, nonce);

	}
}