分别用java和javaScript实现md5验签算法

在金融领域，牵涉到下单支付的接口，为了增加接口的安全性（防止中间人攻击），增加md5签名算法。分别用java和javaScript实现，测试签名结果一致，大家可以放心使用。
md5验签算法主要有以下几步：
1，将请求头head和请求体body合并, 并剔除key值为sign的选项，因为签名本身不参与计算；
2，将参数名key按照ASCII码从小到大排序（字典序），参数名区分大小写；
3，如果key或者value的值为null或者空字符串则不参与签名；
4，将签名密钥和待签名字符串一起进行md5算法计算，得到签名sign值

java实现

HashMap<String, String> params = new HashMap<String, String>();
HashMap<String, String> head   = new HashMap<String, String>();

head.put("trans_code", "0001");
head.put("chnlId", "01");
head.put("chnlUserId", "da91d3a936f34fad82788892c4574e43b");
head.put("sessionId", "4cfjejenddu1fcd4b6eaa4f8db4fe628a8a");
head.put("timestamp", System.currentTimeMillis());

HashMap<String, String> body = new HashMap<String, String>();
body.put("bakNo", "77777777777");
body.put("productNo", "66666666666");
body.put("accountNum", 3);
body.put("moduleType", "1");
String sign = NetUtils.getSign(head, body);   // 进行签名计算
head.put("sign", "'" + sign + "'");

params.put("syshead", head.toString());
params.put("body", body.toString());

String msgId = "0001";

String url = "";  
net.execute(url, params, new NetMessage(msgId));

NetUtils.java

public class NetUtils {

    public static String getSign(HashMap<String, String> head, HashMap<String, String> body) {
        HashMap<String, String> signMap = new HashMap<String, String>();
        signMap.putAll(body);
        signMap.putAll(head);//head中的参数覆盖body
        signMap.remove("sign");

        return getSign(signMap);
    }

    public static String getSign(HashMap<String, String> requestParams) {
        List<Map.Entry<String, String>> infoIds = new ArrayList<Map.Entry<String, String>>
                (requestParams.entrySet());

        // 对HashMap中的key 进行排序
        Collections.sort(infoIds, new Comparator<Map.Entry<String, String>>() {
            public int compare(Map.Entry<String, String> o1, Map.Entry<String, String> o2) {
                return (o1.getKey()).toString().compareTo(o2.getKey().toString());
            }
        });

        StringBuilder paramsBuilder = new StringBuilder("");
        for (int i = 0; i < infoIds.size(); i++) {
            String key = infoIds.get(i).getKey();
            String value = infoIds.get(i).getValue();
            if (TextUtils.isEmpty(key) || TextUtils.isEmpty(value) || "''".equals(value) || "'null'".equals(value)) {
                continue;
            }
            paramsBuilder.append(key + value);
        }

        //验证密钥
        String confirmKey = "";

        //md5计算,原map中value大多加了单引号，需要去除
        String md1 = getMD5(confirmKey + paramsBuilder.toString().replaceAll("'", ""));

        if (md1 != null) {
            String md2 = getMD5(md1.substring(0, 5) + md1.substring(md1.length() - 5, md1.length()));
            return md2.toUpperCase();//转大写
        }

        return "";
    }

    public static String getMD5(String data) {

        MessageDigest md = null;
        try {
            md = MessageDigest.getInstance("MD5");
            md.update(data.getBytes());
            byte byteData[] = md.digest();

            StringBuffer result = new StringBuffer();
            for (int i = 0; i < byteData.length; i++) {
                result.append(Integer.toString((byteData[i] & 0xff) + 0x100, 16).substring(1));
            }
            return result.toString();
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
        return "";
    }
}

javaScript实现

安装md5:

npm install md5 --save

import md5 from 'md5';
var data = {
    "syshead": {
        "trans_code": '0001',
        "chnlId": '01',
        "chnlUserId": 'da91d3a936f34fad82788892c4574e43b',
        "sessionId": '4cfjejenddu1fcd4b6eaa4f8db4fe628a8a',
        "timestamp": new Date().getTime()
    },
    "body": {
        "bakNo": '77777777777',
        "productNo": '66666666666',
        "accountNum": 3,
        "moduleType": '1'
    }
}
data.syshead.sign = me.getSign(data.syshead, data.body);

获取md5签名

getSign(syshead, body) {
    let signObj = {};
    Object.assign(signObj, syshead, body);
    delete signObj.sign;
    function getSignString(params) {
        let arr = [];
        for (let key in params) {
            if (!key || !params[key]) {
                continue;
            }
            arr.push(key + params[key]);
        }
        return arr.sort().join('').replace(/\'/g, "");

    }
    let sign = getSignString(signObj); //获取签名字符串sign
    //验证密钥
    let confirmKey = '';
    //md5计算
    let md1 = md5(confirmKey + sign);

    if (md1) {
        let md2 = md5(md1.substring(0, 5) + md1.substring(md1.length - 5, md1.length));
        return md2.toUpperCase();//转大写
    }
    return "";
}