一款JavaScript 混淆(Obfuscator)工具(Tool)的研究(七）更新2

之前系列中的 花指令和控制流平坦化 ，其中的控制流的变化似乎不大，但是死代码注入这个似乎是进行了较大的升级。

deadCodeInjection

Type: boolean Default: false

⚠️ Dramatically increases size of obfuscated code (up to 200%), use only if size of obfuscated code doesn't matter. Use deadCodeInjectionThreshold to set percentage of nodes that will affected by dead code injection.

显着增加混淆代码的大小（高达 200%），仅当混淆代码的大小无关紧要时才使用。使用 deadCodeInjectionThreshold 设置将受死代码注入影响的节点的百分比。

⚠️ This option forcibly enables stringArray option.

With this option, random blocks of dead code will be added to the obfuscated code.

使用此选项，死代码的随机块将添加到混淆代码中。

看页面下方的例子：

// input
(function(){
    if (true) {
        var foo = function () {
            console.log('abc');
        };
        var bar = function () {
            console.log('def');
        };
        var baz = function () {
            console.log('ghi');
        };
        var bark = function () {
            console.log('jkl');
        };
        var hawk = function () {
            console.log('mno');
        };

        foo();
        bar();
        baz();
        bark();
        hawk();
    }
})();

// output
var _0x37b8 = [
    'YBCtz',
    'GlrkA',
    'urPbb',
    'abc',
    'NMIhC',
    'yZgAj',
    'zrAId',
    'EtyJA',
    'log',
    'mno',
    'jkl',
    'def',
    'Quzya',
    'IWbBa',
    'ghi'
];
function _0x43a7(_0x12cf56, _0x587376) {
    _0x43a7 = function (_0x2f87a8, _0x47eac2) {
        _0x2f87a8 = _0x2f87a8 - (0x16a7 * 0x1 + 0x5 * 0x151 + -0x1c92);
        var _0x341e03 = _0x37b8[_0x2f87a8];
        return _0x341e03;
    };
    return _0x43a7(_0x12cf56, _0x587376);
}
(function () {
    if (!![]) {
        var _0xbbe28f = function () {
            var _0x2fc85f = _0x43a7;
            if (_0x2fc85f(0xaf) === _0x2fc85f(0xae)) {
                _0x1dd94f[_0x2fc85f(0xb2)](_0x2fc85f(0xb5));
            } else {
                console[_0x2fc85f(0xb2)](_0x2fc85f(0xad));
            }
        };
        var _0x5e46bc = function () {
            var _0x15b472 = _0x43a7;
            if (_0x15b472(0xb6) !== _0x15b472(0xaa)) {
                console[_0x15b472(0xb2)](_0x15b472(0xb5));
            } else {
                _0x47eac2[_0x15b472(0xb2)](_0x15b472(0xad));
            }
        };
        var _0x3669e8 = function () {
            var _0x47a442 = _0x43a7;
            if (_0x47a442(0xb7) !== _0x47a442(0xb0)) {
                console[_0x47a442(0xb2)](_0x47a442(0xb8));
            } else {
                _0x24e0bf[_0x47a442(0xb2)](_0x47a442(0xb3));
            }
        };
        var _0x28b05a = function () {
            var _0x497902 = _0x43a7;
            if (_0x497902(0xb1) === _0x497902(0xb1)) {
                console[_0x497902(0xb2)](_0x497902(0xb4));
            } else {
                _0x59c9c6[_0x497902(0xb2)](_0x497902(0xb4));
            }
        };
        var _0x402a54 = function () {
            var _0x1906b7 = _0x43a7;
            if (_0x1906b7(0xab) === _0x1906b7(0xac)) {
                _0xb89cd0[_0x1906b7(0xb2)](_0x1906b7(0xb8));
            } else {
                console[_0x1906b7(0xb2)](_0x1906b7(0xb3));
            }
        };
        _0xbbe28f();
        _0x5e46bc();
        _0x3669e8();
        _0x28b05a();
        _0x402a54();
    }
}());

 这个是添加了一些辣鸡if分支。这个先通过函数把字符串还原，然后再判断if条件，是可以去掉这些辣鸡分支的。

混淆代码源码：GitHub - javascript-obfuscator/javascript-obfuscator: A powerful obfuscator for JavaScript and Node.js

其中的混淆代码的模版在：

.\javascript-obfuscator-master\src\custom-code-helpers

里边的templates 都是替换的case。

其他变化不再介绍，请各位自行学习！