javascript - 这种类型的JS加密怎么破解？-PHP Tutorial-php.cn

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javascript - 这种类型的JS加密怎么破解？

WBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWB

Jun 06, 2016 pm 08:45 PM

javascriptphp

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</code>

回复内容：

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</code>

这种简单的东西压根起不到加密的效果，骗骗小孩罢了。
原理上无非就是将JS代码作为字符串，对这个字符串进行escape一类的混淆，执行时不过unescape再eval一下。

<code>this.eval=function (s) {
  console.log(s);
};
</code>

这样不就能得到原来的代码了么：

<code>var fangke_xHead = document.getElementsByTagName('HEAD').item(0);
var para = document.getElementById("qq_js");
var v;
var v = para.src;
var tmp = v.split("?");
var ids = tmp[1];
var url = tmp[0].split("Count.js");

function skip() {
    if (document.getElementById('QQfangke_iframe') == null) {
        var QQfangke_xurl = 'http://qq-812631263.huantu.net/T-census.php?' + ids;
        var QQfangke_ref = encodeURIComponent(document.referrer);
        var QQfangke_page = encodeURIComponent(document.location.href);
        var QQfangke_url = QQfangke_xurl + '&url=' + url[0] + '&llurl=' + QQfangke_ref + '&thepage=' + QQfangke_page + '&t=' + new Date().getTime();
        var iframe = document.createElement("iframe");
        iframe.src = QQfangke_url;
        iframe.id = "QQfangke_iframe";
        iframe.name = "QQfangke_iframe";
        iframe.style.width = "0px";
        iframe.style.height = "0px";
        iframe.scrolling = "no";
        iframe.setAttribute('frameborder', '0', 0);
        document.body.appendChild(iframe)
    }
}
skip();
</code>

举一隅不以三隅反，则免不了调试代码通宵～
我没有明说的是，它的代码进行了好几次的解码，所以原代码第一次运行时，eval方法截获的字符串仍然是一个"eval(SubstantialCode)"形式的字符串，所以需要将其中SubstantialCode再执行一次，反复此方法，最终eval会截获到原始的代码。
大致这样吧：

<code>var _eval=this.eval;
this.eval=function (s) {
  if (s.indexOf("eval")==0) 
    _eval(s);
  else 
    console.log(s);
};
</code>

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PHP is suitable for web development and rapid prototyping, and Python is suitable for data science and machine learning. 1.PHP is used for dynamic web development, with simple syntax and suitable for rapid development. 2. Python has concise syntax, is suitable for multiple fields, and has a strong library ecosystem.

PHP and Frameworks: Modernizing the LanguageApr 18, 2025 am 12:14 AM

PHP remains important in the modernization process because it supports a large number of websites and applications and adapts to development needs through frameworks. 1.PHP7 improves performance and introduces new features. 2. Modern frameworks such as Laravel, Symfony and CodeIgniter simplify development and improve code quality. 3. Performance optimization and best practices further improve application efficiency.

PHP's Impact: Web Development and BeyondApr 18, 2025 am 12:10 AM

PHPhassignificantlyimpactedwebdevelopmentandextendsbeyondit.1)ItpowersmajorplatformslikeWordPressandexcelsindatabaseinteractions.2)PHP'sadaptabilityallowsittoscaleforlargeapplicationsusingframeworkslikeLaravel.3)Beyondweb,PHPisusedincommand-linescrip

How does PHP type hinting work, including scalar types, return types, union types, and nullable types?Apr 17, 2025 am 12:25 AM

PHP type prompts to improve code quality and readability. 1) Scalar type tips: Since PHP7.0, basic data types are allowed to be specified in function parameters, such as int, float, etc. 2) Return type prompt: Ensure the consistency of the function return value type. 3) Union type prompt: Since PHP8.0, multiple types are allowed to be specified in function parameters or return values. 4) Nullable type prompt: Allows to include null values and handle functions that may return null values.

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