theme: channing-cyan
关键词
JS 混淆、源码乱码、参数动态加密
逆向目标
题目1：抓取所有（5页）机票的价格，并计算所有机票价格的平均值，填入答案。
逆向过程
解决无限debug
打开 F12 刷新页面，傻眼了。页面无法继续下翻...
陷入了无限debug!!
解决：Never pause here 不在此处下断
在debugger位置，点击行号，右键Never pause here，永远不在此处断下，然后重新刷新就可以过这第一个小坑。
抓包分析
接着我们需要找到目标url。
上下翻页，我们很快能够找到具体数据响应的接口。
请求详情：
响应：
参数page无需多言，关键是有个不知道哪里冒出来的参数m？
将
curl命令转换为Python、JavaScript等: https://curlconverter.com/
此时，如果我们构造requests请求，并不带上m查询参数，执行会发现响应结果为：
{'error': 'token failed'}
接下来就是要分析下这个m是怎么带上的？
调用堆栈
很容易猜想后半部分大概率是一个时间戳，前半部分是被加密的字符串，中间用中文的|连接。
由于
params参数是封装到请求体中发到服务器的，所以，参数m的生成必然是在请求前，因此可以直接来到请求时的这个栈中进行查看调试。
在点进去显示的那一行打断点刷新调试一下，会发现在_0xb89747已经是加密完成的参数，肯定加密过程是在这之前完成的。
所以往回找，先根据_0xb89747看看是从哪里来的，发现是:
var _0xb89747 = _0x5d83a3;
同理再往回找_0x5d83a3从哪里来，发现_0x5d83a3是定义的对象，然后往里面塞了什么东西进去组成的:
const _0x5d83a3 = {};
_0x5d83a3['\x70\x61\x67\x65'] = window['\x70\x61\x67\x65'],
_0x5d83a3['\x6d'] = _0x57feae + '\u4e28' + _0x2268f9 / (-1 * 3483 + -9059 + 13542);
根据_0xb89747为{"page": 4, "m": "8d596e76013033e75c3e23015c553c55丨1715257368"}能够得出参数里面m的组成：
_0x57feae就是前半部分被加密完成的东西。_0x2268f9就是后半部分。
是不是真相快被找到了，再往回找这两个是哪里来的：
var _0x2268f9 = Date['\x70\x61\x72\x73\x65'](new Date()) + (16798545 + -72936737 + 156138192)
, _0x57feae = oo0O0(_0x2268f9['\x74\x6f\x53\x74\x72' + '\x69\x6e\x67']()) + window['\x66'];
在线网站解混淆
通过堆栈跟踪，我们已经找到m参数加密入口，但是代码是混淆的，看起来并不那么清晰。
找在线网站，稍微解一下混淆:
https://deobfuscator.kuizuo.cn/
function a() {
var _0x2268f9 = Date.parse(new Date()) + 100000000;
var _0x57feae = oo0O0(_0x2268f9.toString()) + window.f;
const _0x5d83a3 = {
page: window.page,
m: _0x57feae + "丨" + _0x2268f9 / 1000
};
var _0xb89747 = _0x5d83a3;
$.ajax({
url: window.url,
dataType: "json",
async: false,
data: _0xb89747,
type: "GET",
beforeSend: function (_0x4c488e) {},
success: function (_0x131e59) {
_0x131e59 = _0x131e59.data;
let _0x354583 = "";
let _0x1b89ba = "中国联合航空KN5911波音737(中)13:50
大兴国际机场
3小时40分钟17:30
宝安机场
¥price_sole
收起
";
let _0x548377 = ["中国南方航空", "吉祥航空", "奥凯航空", "九元航空", "长龙航空", "东方航空", "中国国际航空", "深圳航空", "海南航空", "春秋航空", "上海航空", "西部航空", "重庆航空", "西藏航空", "中国联合航空", "云南祥鹏航空", "云南英安航空", "厦门航空", "天津航空", "山东航空", "四川航空", "华夏航空", "长城航空", "成都航空有", "北京首都航空", "中华航空", "意大利国家航空公司", "印度百捷航空", "越南航空", "远东航空", "印度航空公司", "印度捷特航空有限公司", "以色列航空公司", "意大利航空", "伊朗航空公司", "印度尼西亚鹰航空公司", "英国航空公司", "西方天空航空", "西捷航空", "西班牙欧洲航空公司", "西班牙航空公司", "中国南方航空", "吉祥航空", "奥凯航空", "九元航空", "长龙航空", "东方航空", "中国国际航空", "深圳航空", "海南航空", "春秋航空", "上海航空", "西部航空", "重庆航空", "西藏航空", "中国联合航空", "云南祥鹏航空", "云南英安航空", "厦门航空", "天津航空", "山东航空", "四川航空", "华夏航空", "长城航空", "成都航空有", "北京首都航空", "中华航空", "意大利国家航空公司", "印度百捷航空", "越南航空", "远东航空", "印度航空公司", "印度捷特航空有限公司", "以色列航空公司", "意大利航空", "伊朗航空公司", "印度尼西亚鹰航空公司", "英国航空公司", "西方天空航空", "西捷航空", "西班牙欧洲航空公司", "西班牙航空公司"];
let _0x5286d2 = 1;
let _0xa24ff9 = ["北京首都国际机场", "上海虹桥国际机场", "上海浦东国际机场", "天津滨海国际机场", "太原武宿机场", "呼和浩特白塔机场", "沈阳桃仙国际机场", "大连周水子国际机场", "长春大房身机场", "哈尔滨阎家岗国际机场", "齐齐哈尔三家子机场", "佳木斯东郊机场", "厦门高崎国际机场", "福州长乐国际机场", "杭州萧山国际机场", "合肥骆岗机场", "宁波栎社机场", "南京禄口国际机场", "广州白云国际机场", "深圳宝安国际机场", "长沙黄花机场", "海口美亚机场", "武汉天河机场", "济南遥墙机场", "青岛流亭机场", "南宁吴墟机场", "三亚凤凰国际机场", "重庆江北国际机场", "成都双流国际机场", "昆明巫家坝国际机场", "昆明长水国际机场", "桂林两江国际机场", "西安咸阳国际机场", "兰州中川机场", "贵阳龙洞堡机场", "拉萨贡嘎机场", "乌鲁木齐地窝堡机场", "南昌向塘机场", "郑州新郑机场", "北京首都国际机场", "上海虹桥国际机场", "上海浦东国际机场", "天津滨海国际机场", "太原武宿机场", "呼和浩特白塔机场", "沈阳桃仙国际机场", "大连周水子国际机场", "长春大房身机场", "哈尔滨阎家岗国际机场", "齐齐哈尔三家子机场", "佳木斯东郊机场", "厦门高崎国际机场", "福州长乐国际机场", "杭州萧山国际机场", "合肥骆岗机场", "宁波栎社机场", "南京禄口国际机场", "广州白云国际机场", "深圳宝安国际机场", "长沙黄花机场", "海口美亚机场", "武汉天河机场", "济南遥墙机场", "青岛流亭机场", "南宁吴墟机场", "三亚凤凰国际机场", "重庆江北国际机场", "成都双流国际机场", "昆明巫家坝国际机场", "昆明长水国际机场", "桂林两江国际机场", "西安咸阳国际机场", "兰州中川机场", "贵阳龙洞堡机场", "拉萨贡嘎机场", "乌鲁木齐地窝堡机场", "南昌向塘机场", "郑州新郑机场"];
if (window.page) {} else {
window.page = 1;
}
$.each(_0x131e59, function (_0x282f1d, _0x4e0853) {
_0x354583 += _0x1b89ba.replace("price_sole", _0x4e0853.value).replace("中国联合航空", _0x548377[_0x5286d2 * window.page]).replace("大兴国际", _0xa24ff9[parseInt(_0x5286d2 * window.page / 2) + 1]).replace("宝安机场", _0xa24ff9[_0xa24ff9.length - parseInt(_0x5286d2 * window.page / 2) - 1]);
_0x5286d2 += 1;
});
$(".m-airfly-lst").text("").append(_0x354583);
},
complete: function () {},
error: function () {
alert("数据拉取失败。可能是触发了风控系统，若您是正常访问，请使用谷歌浏览器无痕模式，并且校准电脑的系统时间重新尝试");
alert("生而为虫，我很抱歉，请刷新页面，查看问题是否存在");
$(".page-message").eq(0).addClass("active");
$(".page-message").removeClass("active");
}
});
}
通过解混淆后的 JS 代码也是进一步验证了我们跟踪堆栈的正确性。
我们可以看到m字符串是通过oo0O0()函数 + window.f + ‘|’ + 时间处理构成的，接下来我们来找oo0O0()这个函数。
跟栈找到oo0O0()函数的定义：
抠出function oo0O0(mw)函数，使用在线 HTML 美化工具美化。
HTML 美化代码工具分析: https://beautifier.io/
function oo0O0(mw)
{
window.b = '';
for (var i = 0, len = window.a.length; i < len; i++)
{
console.log(window.a[i]);
window.b += String[document.e + document.g](window.a[i][document.f +
document.h
]() - i - window.c)
}
var U = ['W5r5W6VdIHZcT8kU', 'WQ8CWRaxWQirAW=='];
var J = function (o, E)
{
o = o - 0x0;
var N = U[o];
if (J['bSSGte'] === undefined)
{
var Y = function (w)
{
var m =
'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789+/=',
T = String(w)['replace'](/=+$/, '');
var A = '';
for (var C = 0x0, b, W, l = 0x0; W = T['charAt'](l++); ~
W && (b = C % 0x4 ? b * 0x40 + W : W, C++ % 0x4) ?
A += String['fromCharCode'](0xff & b >> (-0x2 * C &
0x6)) : 0x0)
{
W = m['indexOf'](W)
}
return A
};
var t = function (w, m)
{
var T = [],
A = 0x0,
C, b = '',
W = '';
w = Y(w);
for (var R = 0x0, v = w['length']; R < v; R++)
{
W += '%' + ('00' + w['charCodeAt'](R)['toString'](
0x10))['slice'](-0x2)
}
w = decodeURIComponent(W);
var l;
for (l = 0x0; l < 0x100; l++)
{
T[l] = l
}
for (l = 0x0; l < 0x100; l++)
{
A = (A + T[l] + m['charCodeAt'](l % m['length'])) %
0x100, C = T[l], T[l] = T[A], T[A] = C
}
l = 0x0, A = 0x0;
for (var L = 0x0; L < w['length']; L++)
{
l = (l + 0x1) % 0x100, A = (A + T[l]) % 0x100, C =
T[l], T[l] = T[A], T[A] = C, b += String[
'fromCharCode'](w['charCodeAt'](L) ^ T[(T[
l] + T[A]) % 0x100])
}
return b
};
J['luAabU'] = t, J['qlVPZg'] = {}, J['bSSGte'] = !![]
}
var H = J['qlVPZg'][o];
return H === undefined ? (J['TUDBIJ'] === undefined && (J[
'TUDBIJ'] = !![]), N = J['luAabU'](N, E), J['qlVPZg'][
o] = N) : N = H, N
};
eval(atob(window['b'])[J('0x0', ']dQW')](J('0x1', 'GTu!'), '\x27' + mw +
'\x27'));
return ''
}
这里我们会发现，oo0O0()这个函数只是执行了eval，而函数本身返回空值""。
优秀啊，年轻人真是会玩！
接下来分析这条代码：
> atob(window['b'])
> 'var hexcase=0;var b64pad="";var chrsz=16;function hex_md5(a){return binl2hex(core_md5(str2binl(a),a.length*chrsz))}function b64_md5(a){return binl2b64(core_md5(str2binl(a),a.length*chrsz))}function str_md5(a){return binl2str(core_md5(str2binl(a),a.length*chrsz))}function hex_hmac_md5(a,b){return binl2hex(core_hmac_md5(a,b))}function b64_hmac_md5(a,b){return binl2b64(core_hmac_md5(a,b))}function str_hmac_md5(a,b){return binl2str(core_hmac_md5(a,b))}function md5_vm_test(){return hex_md5("abc")=="900150983cd24fb0d6963f7d28e17f72"}function core_md5(p,k){p[k>>5]|=128<<((k)%32);p[(((k+64)>>>9)<<4)+14]=k;var o=1732584193;var n=-271733879;var m=-1732584194;var l=271733878;for(var g=0;g16){e=core_md5(e,c.length*chrsz)}var a=Array(16),d=Array(16);for(var b=0;b<16;b++){a[b]=e[b]^909522486;d[b]=e[b]^1549556828}var g=core_md5(a.concat(str2binl(f)),512+f.length*chrsz);return core_md5(d.concat(g),512+128)}function safe_add(a,d){var c=(a&65535)+(d&65535);var b=(a>>16)+(d>>16)+(c>>16);return(b<<16)|(c&65535)}function bit_rol(a,b){return(a<>>(32-b))}function str2binl(d){var c=Array();var a=(1<>5]|=(d.charCodeAt(b/chrsz)&a)<<(b%32)}return c}function binl2str(c){var d="";var a=(1<>5]>>>(b%32))&a)}return d}function binl2hex(c){var b=hexcase?"0123456789ABCDEF":"0123456789abcdef";var d="";for(var a=0;a>2]>>((a%4)*8+4))&15)+b.charAt((c[a>>2]>>((a%4)*8))&15)}return d}function binl2b64(d){var c="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";var f="";for(var b=0;b>2]>>8*(b%4))&255)<<16)|(((d[b+1>>2]>>8*((b+1)%4))&255)<<8)|((d[b+2>>2]>>8*((b+2)%4))&255);for(var a=0;a<4;a++){if(b*8+a*6>d.length*32){f+=b64pad}else{f+=c.charAt((e>>6*(3-a))&63)}}}return f};window.f = hex_md5(mwqqppz)'
atob()函数是JavaScript中的一个内置函数，用于将base64编码的字符串解码为原始字符串。
使用美化工具(**https://beautifier.io/**)美化得到下面可读的`JavaScript`代码：
var hexcase = 0; var b64pad = ""; var chrsz = 16;function hex_md5(a)
{
return binl2hex(core_md5(str2binl(a), a.length * chrsz))
}function b64_md5(a)
{
return binl2b64(core_md5(str2binl(a), a.length * chrsz))
}function str_md5(a)
{
return binl2str(core_md5(str2binl(a), a.length * chrsz))
}function hex_hmac_md5(a, b)
{
return binl2hex(core_hmac_md5(a, b))
}function b64_hmac_md5(a, b)
{
return binl2b64(core_hmac_md5(a, b))
}function str_hmac_md5(a, b)
{
return binl2str(core_hmac_md5(a, b))
}function md5_vm_test()
{
return hex_md5(“abc”) == “900150983cd24fb0d6963f7d28e17f72”
}function core_md5(p, k)
{
p[k >> 5] |= 128 << ((k) % 32);
p[(((k + 64) >>> 9) << 4) + 14] = k;
var o = 1732584193;
var n = -271733879;
var m = -1732584194;
var l = 271733878;
for (var g = 0; g < p.length; g += 16)
{
var j = o;
var h = n;
var f = m;
var e = l;
o = md5_ff(o, n, m, l, p[g + 0], 7, -680976936);
l = md5_ff(l, o, n, m, p[g + 1], 12, -389564586);
m = md5_ff(m, l, o, n, p[g + 2], 17, 606105819);
n = md5_ff(n, m, l, o, p[g + 3], 22, -1044525330);
o = md5_ff(o, n, m, l, p[g + 4], 7, -176418897);
l = md5_ff(l, o, n, m, p[g + 5], 12, 1200080426);
m = md5_ff(m, l, o, n, p[g + 6], 17, -1473231341);
n = md5_ff(n, m, l, o, p[g + 7], 22, -45705983);
o = md5_ff(o, n, m, l, p[g + 8], 7, 1770035416);
l = md5_ff(l, o, n, m, p[g + 9], 12, -1958414417);
m = md5_ff(m, l, o, n, p[g + 10], 17, -42063);
n = md5_ff(n, m, l, o, p[g + 11], 22, -1990404162);
o = md5_ff(o, n, m, l, p[g + 12], 7, 1804660682);
l = md5_ff(l, o, n, m, p[g + 13], 12, -40341101);
m = md5_ff(m, l, o, n, p[g + 14], 17, -1502002290);
n = md5_ff(n, m, l, o, p[g + 15], 22, 1236535329);
o = md5_gg(o, n, m, l, p[g + 1], 5, -165796510);
l = md5_gg(l, o, n, m, p[g + 6], 9, -1069501632);
m = md5_gg(m, l, o, n, p[g + 11], 14, 643717713);
n = md5_gg(n, m, l, o, p[g + 0], 20, -373897302);
o = md5_gg(o, n, m, l, p[g + 5], 5, -701558691);
l = md5_gg(l, o, n, m, p[g + 10], 9, 38016083);
m = md5_gg(m, l, o, n, p[g + 15], 14, -660478335);
n = md5_gg(n, m, l, o, p[g + 4], 20, -405537848);
o = md5_gg(o, n, m, l, p[g + 9], 5, 568446438);
l = md5_gg(l, o, n, m, p[g + 14], 9, -1019803690);
m = md5_gg(m, l, o, n, p[g + 3], 14, -187363961);
n = md5_gg(n, m, l, o, p[g + 8], 20, 1163531501);
o = md5_gg(o, n, m, l, p[g + 13], 5, -1444681467);
l = md5_gg(l, o, n, m, p[g + 2], 9, -51403784);
m = md5_gg(m, l, o, n, p[g + 7], 14, 1735328473);
n = md5_gg(n, m, l, o, p[g + 12], 20, -1921207734);
o = md5_hh(o, n, m, l, p[g + 5], 4, -378558);
l = md5_hh(l, o, n, m, p[g + 8], 11, -2022574463);
m = md5_hh(m, l, o, n, p[g + 11], 16, 1839030562);
n = md5_hh(n, m, l, o, p[g + 14], 23, -35309556);
o = md5_hh(o, n, m, l, p[g + 1], 4, -1530992060);
l = md5_hh(l, o, n, m, p[g + 4], 11, 1272893353);
m = md5_hh(m, l, o, n, p[g + 7], 16, -155497632);
n = md5_hh(n, m, l, o, p[g + 10], 23, -1094730640);
o = md5_hh(o, n, m, l, p[g + 13], 4, 681279174);
l = md5_hh(l, o, n, m, p[g + 0], 11, -358537222);
m = md5_hh(m, l, o, n, p[g + 3], 16, -722881979);
n = md5_hh(n, m, l, o, p[g + 6], 23, 76029189);
o = md5_hh(o, n, m, l, p[g + 9], 4, -640364487);
l = md5_hh(l, o, n, m, p[g + 12], 11, -421815835);
m = md5_hh(m, l, o, n, p[g + 15], 16, 530742520);
n = md5_hh(n, m, l, o, p[g + 2], 23, -995338651);
o = md5_ii(o, n, m, l, p[g + 0], 6, -198630844);
l = md5_ii(l, o, n, m, p[g + 7], 10, 11261161415);
m = md5_ii(m, l, o, n, p[g + 14], 15, -1416354905);
n = md5_ii(n, m, l, o, p[g + 5], 21, -57434055);
o = md5_ii(o, n, m, l, p[g + 12], 6, 1700485571);
l = md5_ii(l, o, n, m, p[g + 3], 10, -1894446606);
m = md5_ii(m, l, o, n, p[g + 10], 15, -1051523);
n = md5_ii(n, m, l, o, p[g + 1], 21, -2054922799);
o = md5_ii(o, n, m, l, p[g + 8], 6, 1873313359);
l = md5_ii(l, o, n, m, p[g + 15], 10, -30611744);
m = md5_ii(m, l, o, n, p[g + 6], 15, -1560198380);
n = md5_ii(n, m, l, o, p[g + 13], 21, 1309151649);
o = md5_ii(o, n, m, l, p[g + 4], 6, -145523070);
l = md5_ii(l, o, n, m, p[g + 11], 10, -1120210379);
m = md5_ii(m, l, o, n, p[g + 2], 15, 718787259);
n = md5_ii(n, m, l, o, p[g + 9], 21, -343485551);
o = safe_add(o, j);
n = safe_add(n, h);
m = safe_add(m, f);
l = safe_add(l, e)
}
return Array(o, n, m, l)
}function md5_cmn(h, e, d, c, g, f)
{
return safe_add(bit_rol(safe_add(safe_add(e, h), safe_add(c, f)), g), d)
}function md5_ff(g, f, k, j, e, i, h)
{
return md5_cmn((f & k) | ((~f) & j), g, f, e, i, h)
}function md5_gg(g, f, k, j, e, i, h)
{
return md5_cmn((f & j) | (k & (~j)), g, f, e, i, h)
}function md5_hh(g, f, k, j, e, i, h)
{
return md5_cmn(f ^ k ^ j, g, f, e, i, h)
}function md5_ii(g, f, k, j, e, i, h)
{
return md5_cmn(k ^ (f | (~j)), g, f, e, i, h)
}function core_hmac_md5(c, f)
{
var e = str2binl(c);
if (e.length > 16)
{
e = core_md5(e, c.length * chrsz)
}
var a = Array(16),
d = Array(16);
for (var b = 0; b < 16; b++)
{
a[b] = e[b] ^ 909522486;
d[b] = e[b] ^ 1549556828
}
var g = core_md5(a.concat(str2binl(f)), 512 + f.length * chrsz);
return core_md5(d.concat(g), 512 + 128)
}function safe_add(a, d)
{
var c = (a & 65535) + (d & 65535);
var b = (a >> 16) + (d >> 16) + (c >> 16);
return (b << 16) | (c & 65535)
}function bit_rol(a, b)
{
return (a << b) | (a >>> (32 - b))
}function str2binl(d)
{
var c = Array();
var a = (1 << chrsz) - 1;
for (var b = 0; b < d.length * chrsz; b += chrsz)
{
c[b >> 5] |= (d.charCodeAt(b / chrsz) & a) << (b % 32)
}
return c
}function binl2str(c)
{
var d = “”;
var a = (1 << chrsz) - 1;
for (var b = 0; b < c.length * 32; b += chrsz)
{
d += String.fromCharCode((c[b >> 5] >>> (b % 32)) & a)
}
return d
}function binl2hex(c)
{
var b = hexcase ? “0123456789ABCDEF” : “0123456789abcdef”;
var d = “”;
for (var a = 0; a < c.length * 4; a++)
{
d += b.charAt((c[a >> 2] >> ((a % 4) * 8 + 4)) & 15) + b.charAt((c[a >>
2] >> ((a % 4) * 8)) & 15)
}
return d
}
function binl2b64(d)
{
var c = “ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/”;
var f = “”;
for (var b = 0; b < d.length * 4; b += 3)
{
var e = (((d[b >> 2] >> 8 * (b % 4)) & 255) << 16) | (((d[b + 1 >> 2] >>
8 * ((b + 1) % 4)) & 255) << 8) | ((d[b + 2 >> 2] >> 8 * ((b +
2) % 4)) & 255);
for (var a = 0; a < 4; a++)
{
if (b * 8 + a * 6 > d.length * 32)
{
f += b64pad
}
else
{
f += c.charAt((e >> 6 * (3 - a)) & 63)
}
}
}
return f
};
window.f = hex_md5(mwqqppz)
我们发现window.f = hex_md5(mwqqppz)，是通过很多函数加密的，最重要的就是这最后一条，接下来我们来寻找mwqqppz参数。
回到调用oo0O0()函数的部分：
var _0x2268f9 = Date.parse(new Date()) + 100000000;
var _0x57feae = oo0O0(_0x2268f9.toString()) + window.f;
const _0x5d83a3 = {
page: window.page,
m: _0x57feae + "丨" + _0x2268f9 / 1000
};
以及eval()那一条代码，分析传入的参数。
eval(atob(window['b'])[J('0x0', ']dQW')](J('0x1', 'GTu!'), '\x27' + mw + '\x27'));
通过分析，我们发现J函数就在oo0O0函数内定义，我们将J函数抠出:
var U = ['W5r5W6VdIHZcT8kU', 'WQ8CWRaxWQirAW==']; var J = function (o, E) { o = o - 0x0; var N = U[o]; if (J['bSSGte'] === undefined) { var Y = function (w) { var m = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789+/=', T = String(w)['replace'](/=+$/, ''); var A = ''; for (var C = 0x0, b, W, l = 0x0; W = T['charAt'](l++); ~ W && (b = C % 0x4 ? b * 0x40 + W : W, C++ % 0x4) ? A += String['fromCharCode'](0xff & b >> (-0x2 * C & 0x6)) : 0x0) { W = m['indexOf'](W) } return A }; var t = function (w, m) { var T = [], A = 0x0, C, b = '', W = ''; w = Y(w); for (var R = 0x0, v = w['length']; R < v; R++) { W += '%' + ('00' + w['charCodeAt'](R)['toString']( 0x10))['slice'](-0x2) } w = decodeURIComponent(W); var l; for (l = 0x0; l < 0x100; l++) { T[l] = l } for (l = 0x0; l < 0x100; l++) { A = (A + T[l] + m['charCodeAt'](l % m['length'])) % 0x100, C = T[l], T[l] = T[A], T[A] = C } l = 0x0, A = 0x0; for (var L = 0x0; L < w['length']; L++) { l = (l + 0x1) % 0x100, A = (A + T[l]) % 0x100, C = T[l], T[l] = T[A], T[A] = C, b += String[ 'fromCharCode'](w['charCodeAt'](L) ^ T[(T[ l] + T[A]) % 0x100]) } return b }; J['luAabU'] = t, J['qlVPZg'] = {}, J['bSSGte'] = !![] } var H = J['qlVPZg'][o]; return H === undefined ? (J['TUDBIJ'] === undefined && (J[ 'TUDBIJ'] = !![]), N = J['luAabU'](N, E), J['qlVPZg'][ o] = N) : N = H, N };
console.log(J(‘0x0’, ‘]dQW’))
console.log(J(‘0x1’, ‘GTu!’))
并在浏览器执行：
得到:
J('0x0', ']dQW')的值为：replaceJ('0x1', 'GTu!')的值为：mwqqppz
又'\x27' + mw + '\x27'的值为1715257368000，也就是说这里就是某一个字符串进行replace操作，将mwqqppz替换成了时间戳mw，最终这个字符串就是window['b']的值，是一个base64的编码。
eval()部分的代码即可替换为：
eval(atob(window['b'])["replace"]("mwqqppz","1715257368000"));
通过以上分析，我们可以知道window.f = hex_md5(mwqqppz)中mwqqppz就是时间戳mw，这个例子中时间戳mw的值为1715257368000。
mwqqppz字符串本身只是用于标识需要被替换的占位字符串，无特殊含义，然后通过eval执行。
我们手动替换下oo0O0_eval.js中的window.f = hex_md5(mwqqppz)为console.log(hex_md5("1715257368000"))后执行，得到8d596e76013033e75c3e23015c553c55，正是我们之前在控制台分析的_0x57feae的值。
另外，我们通过猴子脚本hook一下window.f也能得到加密算法。
hook脚本：
设置：
翻页调试：
查看第一个箭头所指的栈，清晰的看到加密算法运行时的代码：
// ... // 跟我们解混淆后的代码不能说是一样，只能说是完全相同。 // 此处省略。
function binl2b64(d) {
var c = “ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/”;
var f = “”;
for (var b = 0; b < d.length * 4; b += 3) {
var e = (((d[b >> 2] >> 8 * (b % 4)) & 255) << 16) | (((d[b + 1 >> 2] >> 8 * ((b + 1) % 4)) & 255) << 8) | ((d[b + 2 >> 2] >> 8 * ((b + 2) % 4)) & 255);
for (var a = 0; a < 4; a++) {
if (b * 8 + a * 6 > d.length * 32) {
f += b64pad
} else {
f += c.charAt((e >> 6 * (3 - a)) & 63)
}
}
}
return f
}
;window.f = hex_md5(‘1715257368000’)
完整 JS 加密代码如下：
var window =globalvar hexcase = 0;
var b64pad = “”;
var chrsz = 16;function hex_md5(a) {
return binl2hex(core_md5(str2binl(a), a.length * chrsz))
}function b64_md5(a) {
return binl2b64(core_md5(str2binl(a), a.length * chrsz))
}function str_md5(a) {
return binl2str(core_md5(str2binl(a), a.length * chrsz))
}function hex_hmac_md5(a, b) {
return binl2hex(core_hmac_md5(a, b))
}function b64_hmac_md5(a, b) {
return binl2b64(core_hmac_md5(a, b))
}function str_hmac_md5(a, b) {
return binl2str(core_hmac_md5(a, b))
}function md5_vm_test() {
return hex_md5(“abc”) == “900150983cd24fb0d6963f7d28e17f72”
}function core_md5(p, k) {
p[k >> 5] |= 128 << ((k) % 32);
p[(((k + 64) >>> 9) << 4) + 14] = k;
var o = 1732584193;
var n = -271733879;
var m = -1732584194;
var l = 271733878;
for (var g = 0; g < p.length; g += 16) {
var j = o;
var h = n;
var f = m;
var e = l;
o = md5_ff(o, n, m, l, p[g + 0], 7, -680976936);
l = md5_ff(l, o, n, m, p[g + 1], 12, -389564586);
m = md5_ff(m, l, o, n, p[g + 2], 17, 606105819);
n = md5_ff(n, m, l, o, p[g + 3], 22, -1044525330);
o = md5_ff(o, n, m, l, p[g + 4], 7, -176418897);
l = md5_ff(l, o, n, m, p[g + 5], 12, 1200080426);
m = md5_ff(m, l, o, n, p[g + 6], 17, -1473231341);
n = md5_ff(n, m, l, o, p[g + 7], 22, -45705983);
o = md5_ff(o, n, m, l, p[g + 8], 7, 1770035416);
l = md5_ff(l, o, n, m, p[g + 9], 12, -1958414417);
m = md5_ff(m, l, o, n, p[g + 10], 17, -42063);
n = md5_ff(n, m, l, o, p[g + 11], 22, -1990404162);
o = md5_ff(o, n, m, l, p[g + 12], 7, 1804660682);
l = md5_ff(l, o, n, m, p[g + 13], 12, -40341101);
m = md5_ff(m, l, o, n, p[g + 14], 17, -1502002290);
n = md5_ff(n, m, l, o, p[g + 15], 22, 1236535329);
o = md5_gg(o, n, m, l, p[g + 1], 5, -165796510);
l = md5_gg(l, o, n, m, p[g + 6], 9, -1069501632);
m = md5_gg(m, l, o, n, p[g + 11], 14, 643717713);
n = md5_gg(n, m, l, o, p[g + 0], 20, -373897302);
o = md5_gg(o, n, m, l, p[g + 5], 5, -701558691);
l = md5_gg(l, o, n, m, p[g + 10], 9, 38016083);
m = md5_gg(m, l, o, n, p[g + 15], 14, -660478335);
n = md5_gg(n, m, l, o, p[g + 4], 20, -405537848);
o = md5_gg(o, n, m, l, p[g + 9], 5, 568446438);
l = md5_gg(l, o, n, m, p[g + 14], 9, -1019803690);
m = md5_gg(m, l, o, n, p[g + 3], 14, -187363961);
n = md5_gg(n, m, l, o, p[g + 8], 20, 1163531501);
o = md5_gg(o, n, m, l, p[g + 13], 5, -1444681467);
l = md5_gg(l, o, n, m, p[g + 2], 9, -51403784);
m = md5_gg(m, l, o, n, p[g + 7], 14, 1735328473);
n = md5_gg(n, m, l, o, p[g + 12], 20, -1921207734);
o = md5_hh(o, n, m, l, p[g + 5], 4, -378558);
l = md5_hh(l, o, n, m, p[g + 8], 11, -2022574463);
m = md5_hh(m, l, o, n, p[g + 11], 16, 1839030562);
n = md5_hh(n, m, l, o, p[g + 14], 23, -35309556);
o = md5_hh(o, n, m, l, p[g + 1], 4, -1530992060);
l = md5_hh(l, o, n, m, p[g + 4], 11, 1272893353);
m = md5_hh(m, l, o, n, p[g + 7], 16, -155497632);
n = md5_hh(n, m, l, o, p[g + 10], 23, -1094730640);
o = md5_hh(o, n, m, l, p[g + 13], 4, 681279174);
l = md5_hh(l, o, n, m, p[g + 0], 11, -358537222);
m = md5_hh(m, l, o, n, p[g + 3], 16, -722881979);
n = md5_hh(n, m, l, o, p[g + 6], 23, 76029189);
o = md5_hh(o, n, m, l, p[g + 9], 4, -640364487);
l = md5_hh(l, o, n, m, p[g + 12], 11, -421815835);
m = md5_hh(m, l, o, n, p[g + 15], 16, 530742520);
n = md5_hh(n, m, l, o, p[g + 2], 23, -995338651);
o = md5_ii(o, n, m, l, p[g + 0], 6, -198630844);
l = md5_ii(l, o, n, m, p[g + 7], 10, 11261161415);
m = md5_ii(m, l, o, n, p[g + 14], 15, -1416354905);
n = md5_ii(n, m, l, o, p[g + 5], 21, -57434055);
o = md5_ii(o, n, m, l, p[g + 12], 6, 1700485571);
l = md5_ii(l, o, n, m, p[g + 3], 10, -1894446606);
m = md5_ii(m, l, o, n, p[g + 10], 15, -1051523);
n = md5_ii(n, m, l, o, p[g + 1], 21, -2054922799);
o = md5_ii(o, n, m, l, p[g + 8], 6, 1873313359);
l = md5_ii(l, o, n, m, p[g + 15], 10, -30611744);
m = md5_ii(m, l, o, n, p[g + 6], 15, -1560198380);
n = md5_ii(n, m, l, o, p[g + 13], 21, 1309151649);
o = md5_ii(o, n, m, l, p[g + 4], 6, -145523070);
l = md5_ii(l, o, n, m, p[g + 11], 10, -1120210379);
m = md5_ii(m, l, o, n, p[g + 2], 15, 718787259);
n = md5_ii(n, m, l, o, p[g + 9], 21, -343485551);
o = safe_add(o, j);
n = safe_add(n, h);
m = safe_add(m, f);
l = safe_add(l, e)
}
return Array(o, n, m, l)
}function md5_cmn(h, e, d, c, g, f) {
return safe_add(bit_rol(safe_add(safe_add(e, h), safe_add(c, f)), g), d)
}function md5_ff(g, f, k, j, e, i, h) {
return md5_cmn((f & k) | ((~f) & j), g, f, e, i, h)
}function md5_gg(g, f, k, j, e, i, h) {
return md5_cmn((f & j) | (k & (~j)), g, f, e, i, h)
}function md5_hh(g, f, k, j, e, i, h) {
return md5_cmn(f ^ k ^ j, g, f, e, i, h)
}function md5_ii(g, f, k, j, e, i, h) {
return md5_cmn(k ^ (f | (~j)), g, f, e, i, h)
}function core_hmac_md5(c, f) {
var e = str2binl(c);
if (e.length > 16) {
e = core_md5(e, c.length * chrsz)
}
var a = Array(16),
d = Array(16);
for (var b = 0; b < 16; b++) {
a[b] = e[b] ^ 909522486;
d[b] = e[b] ^ 1549556828
}
var g = core_md5(a.concat(str2binl(f)), 512 + f.length * chrsz);
return core_md5(d.concat(g), 512 + 128)
}function safe_add(a, d) {
var c = (a & 65535) + (d & 65535);
var b = (a >> 16) + (d >> 16) + (c >> 16);
return (b << 16) | (c & 65535)
}function bit_rol(a, b) {
return (a << b) | (a >>> (32 - b))
}function str2binl(d) {
var c = Array();
var a = (1 << chrsz) - 1;
for (var b = 0; b < d.length * chrsz; b += chrsz) {
c[b >> 5] |= (d.charCodeAt(b / chrsz) & a) << (b % 32)
}
return c
}function binl2str(c) {
var d = “”;
var a = (1 << chrsz) - 1;
for (var b = 0; b < c.length * 32; b += chrsz) {
d += String.fromCharCode((c[b >> 5] >>> (b % 32)) & a)
}
return d
}function binl2hex(c) {
var b = hexcase ? “0123456789ABCDEF” : “0123456789abcdef”;
var d = “”;
for (var a = 0; a < c.length * 4; a++) {
d += b.charAt((c[a >> 2] >> ((a % 4) * 8 + 4)) & 15) + b.charAt((c[a >>
2] >> ((a % 4) * 8)) & 15)
}
return d
}function binl2b64(d) {
var c = “ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/”;
var f = “”;
for (var b = 0; b < d.length * 4; b += 3) {
var e = (((d[b >> 2] >> 8 * (b % 4)) & 255) << 16) | (((d[b + 1 >> 2] >>
8 * ((b + 1) % 4)) & 255) << 8) | ((d[b + 2 >> 2] >> 8 * ((b +
2) % 4)) & 255);
for (var a = 0; a < 4; a++) {
if (b * 8 + a * 6 > d.length * 32) {
f += b64pad
} else {
f += c.charAt((e >> 6 * (3 - a)) & 63)
}
}
}
return f
};// window.f = hex_md5(mwqqppz)
// console.log(hex_md5(“1715257368000”))
// 整合hex_md5的参数
function get_m_value() {
var _0x2268f9 = Date[“parse”](new Date()) + 100000000;
// var _0x2268f9 = 1715257368000
var mwqqppz = _0x2268f9"toString";
var m = hex_md5(mwqqppz);
var m_value = m + ‘丨’ + _0x2268f9 / 1000;
return m_value;
};
console.log(get_m_value())
在pycharm中运行结果如下：
和浏览器分析时的m值一致，JS逆向过程结束。
大功告成
逆向结束，剩下的编码就是模拟请求，解析结果了。
将
curl命令转换为Python、JavaScript等: https://curlconverter.com/
老规矩，借用curl命令转代码工具快速生成代码，略作修改即可，重点是逆向过程分析。
#! -*-conding=: UTF-8 -*-import execjs
import requestscookies = {
‘tk’: ‘改成自己的tk’,
‘sessionid’: ‘改成自己的sessionid’,
}headers = {
‘authority’: ‘match.yuanrenxue.cn’,
‘accept’: ‘application/json, text/javascript, /; q=0.01’,
‘accept-language’: ‘zh-CN,zh;q=0.9’,
‘cache-control’: ‘no-cache’,
# ‘cookie’: ‘tk=7699535563564611254; sessionid=0qtsyidunti3daajuz7l2qkqy3m0knmd’,
‘pragma’: ‘no-cache’,
‘referer’: ‘第一题 js混淆源码乱码 - 猿人学’,
‘sec-ch-ua’: ‘“Not A(Brand”;v=“99”, “Google Chrome”;v=“121”, “Chromium”;v=“121”’,
‘sec-ch-ua-mobile’: ‘?0’,
‘sec-ch-ua-platform’: ‘“Windows”’,
‘sec-fetch-dest’: ‘empty’,
‘sec-fetch-mode’: ‘cors’,
‘sec-fetch-site’: ‘same-origin’,
‘user-agent’: ‘Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/121.0.0.0 Safari/537.36’,
‘x-requested-with’: ‘XMLHttpRequest’,
}params = {
‘page’: 1,
‘m’: ‘’,
}def calculate_m_value():
with open(‘_m.js’, mode=‘r’, encoding=‘utf-8’) as f:
JsData = f.read()
m_value = execjs.compile(JsData).call(‘get_m_value’)
# m_value_process = m_value.replace(“丨”, “%E4%B8%A8”)
return m_valuedef main() -> int:
_sum = 0
times = 0
for page_number in range(1, 6):
params[“page”] = page_number
params[“m”] = calculate_m_value()
print(params)
response = requests.get(‘https://match.yuanrenxue.cn/api/match/1’, params=params, cookies=cookies,
headers=headers).json()for data in response["data"]: _sum += data["value"] times += 1 if not times: return 0 return int(_sum / times)
if name == “main”:
result = main()
print(int(result))
结语
至此，这次逆向之旅终于结束了。
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这是一个从 https://juejin.cn/post/7369023361954332698 下的原始话题分离的讨论话题