Web前端安全探秘：技术理论与现实应用

前言

Web前端安全是个新概念，可以理解为它是Web安全防护领域的一部分。

早些时候，曾被狭义的认为前端安全即JS安全。倒是没有错，但不全面。目前来看，应该说：前端代码安全(JS代码安全)+ 前端攻击入侵防护功能 = Web前端安全。

也可以通俗的解释为：Web前端安全，包含：JS代码安全、Web前端安全防护两个方面。

为什么要做Web前端安全工作?

简短的概述而言：做好Web前端安全，可以防止很多Web安全事件的发生。比如：Web页面功能被分析、JS\H5应用被复制或盗用、正常功能被篡改;还比如：防止爬虫、防止自动化攻击、防止SQL注入、防止XSS攻击、防止CRSF等等。

看到这里，不要疑惑，上面没打错字：Web前端安全做好了，可以实现很多本该是WAF才有的安全防护效果。

如果安全要求不是非常高，很多中小企业的Web防护，完全可以在Web前端实现。

Web前端安全实操

1. JS代码安全

Web页面功能，都是由JS代码实现的。JS代码公开透明的特点，使代码谁都可以任意查看，这就带来了如：被分析、复制、盗用、功能篡改等一系列安全隐患。

知名的事件如：锤子手机发布时销量造假事件、小米手机英国众筹作弊事件，都是由于JS代码未保护而直接导致的。

JS代码经过混淆加密后，会变成不可读、不可分析、不可盗用(代码可与域名绑定)的安全代码，可极大的提高前端功能安全性。

JS代码混淆加密，有专业的平台工具，比如：JShaman。

一段未经保护的代码，如：

function hello_world()  
{   
alert("hello world");  
}   
hello_world(); 

经JShaman混淆加密，低强度的保护结果，代码会变为：

var _0x5f2d=['hello\x20world'];(function(_0x1d7bcc,_0x3c8ae3){var _0x51bb3c=function(_0x1df202){while(--_0x1df202){_0x1d7bcc['\x70\x75\x73\x68'](_0x1d7bcc['\x73\x68\x69\x66\x74']());}};_0x51bb3c(++_0x3c8ae3);}(_0x5f2d,0x121));var _0xd5f2=function(_0x32a75d,_0x18d324){_0x32a75d_0x32a75d=_0x32a75d-0x0;var    _0x462cef=_0x5f2d[_0x32a75d];return _0x462cef;};function hello_world(){alert(_0xd5f2('0x0'));}hello_world(); 

到这里，也许有人会有异意：eval也是可以对JS代码进行加密的。此言差异，eval早已经被玩坏了，还原eval加密代码的办法简直是千千万。而这种混淆加密的方式，保护后的代码是不可逆的。

也许上面的保护结果还不够安全?那么将加密强度调高一些，结果可成为:

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代码已变的完全不可读、不可逆，更无法理解代码含义了。代码安全性真正得到了极大提高。当然，功能上与混淆加密前是无异的，不影响正常运行。

这样前端代码(JS代码)安全问题得到了解决。

想必不少人对JS混淆加密是熟悉的，上面的内容还称不上是硬货。那么接下来，是展示黑魔法的时候了。

2. Web前端防护

（编辑：ASP站长网）