This is a tool built to unpack javascript bundles prudiced by webpack and browserify.
[You can use webpack to bundle the ouput source files from this tool and run on the browser](compiling the ouput from debundle.md)
npm i -g @scil/reliable-debundle
$ debundle
Usage: debundle [input file] {OPTIONS}
Options:
--input, -i Bundle to debundle
--output, -o Directory to debundle code into.
--config, -c Configuration file
$ curl https://raw.githubusercontent.com/1egoman/debundle/master/test_bundles/browserify/bundle.js > bundle.js
$ curl https://raw.githubusercontent.com/1egoman/debundle/master/test_bundles/browserify/debundle.config.json > debundle.config.json
$ cat debundle.config.json
{
"type": "browserify",
"knownPaths": {}
}
$ debundle -i bundle.js -o dist/ -c debundle.config.json
$ tree dist/
dist/
├── index.js
└── node_modules
├── number
│ └── index.js
└── uuid
├── index.js
├── lib
│ ├── bytesToUuid.js
│ └── rng.js
├── v1.js
└── v4.js
4 directories, 7 files
The simplest way is use "replaceRequires": "variable",
but in the produced js files, n(1)
would not support code jumping in Intellij Idea family products currently.
To use code jumping, wait for a better Intellij Idea, or use "replaceRequires": "inline,variable",
{
"type": "webpack",
"entryPoint": 0,
"moduleAst": ["body", 0, "expression", "argument", "arguments", 0],
"keepDeeperThan": 3,
"inDescendantsOfSameNameDeclaraton": "keep",
"replaceRequires": "inline,variable",
"replaceModules": "variable",
"replaceExports": "variable",
"variableType": "const",
"require_visitors": {
"convertRequireBind": {
"enable": 1
}
},
"other_visitors": {
"friendlyBool": {
"enable": 1
},
"friendlyExports": {
"enable": 1,
"regexp": "^require\\.d\\(t, ['\"](\\w+?)['\"],\\s*function\\s*\\(\\)\\s*\\{\\s+return ([^;]+);\\s+\\}\\)",
"deleteOld": 0
},
"reduceComma": {
"enable": 1,
"support_nest": 0
}
},
"replaceResultString":{
"from": "e.exports = require('electron');",
"to": "//e.exports = require('electron');",
"regexp": 0,
"all": 1
},
"filters": {
"js-beautify": {
"enable": 0,
"break_chained_methods": true
},
"prettier": {
"enable": 1
}
},
"knownPaths": {}
}
Always use variable
for replaceModules
and replaceExports
. Because inline
for both is not supported fully, most times
e
and t
would not be replaced.
return function(){return m1,m2}, n;
but maybe not fully guaranteed because reduceComma
change ast during tree travel.
Maybe a better ways is to set multiple visitors for reduceComma
"reduceComma": {
"enable": 1,
"support_nest": 0
},
"reduceComma": {
"enable": 1,
"support_nest": 0
}
require.d(t, 'c', function () {
return F1;
}), require.d(t, 'd', function () {
return F2;
});
and at the bottom of a module put following code
exports.c = F1;
exports.d = F2;
There code allow you jump and refactor in Intellij Idea products.
'"deleteOld": 1' would drop origian code, providing more terse code, but cause errors in the following case
r.d(t, "o", function () { return o; });
r.d(t, "setup", function () { return setup; });
let o = 'not ready';
const setup = () => ( o = 'ok' );
when this module is exectuted, o==="not ready"
. but in a real-life app, after setup()
, o==="not ready"
.
If r.d(t, "o", function () { return o; });
is dropped, o
is alway equal to "not really"
.
It would produce new statement require('./bcs1');
from require.bind(null, 'bcs1')
require_visitors
works for the node found related with require
. This type of visitors can created new code and find and replace require
in the new code.
set to '393'
when the webpack runtime code in bundle file is like
!function (e) {
var t = {};
function r(n) {
if (t[n]) return t[n].exports;
var a = t[n] = {i: n, l: !1, exports: {}};
return e[n].call(a.exports, a, a.exports, r), a.l = !0, a.exports
}
...
r.p = "", r(r.s = 393)
}
set to 'jbcS'
if something like
i.push(["jbcS", 13]), r()
find other examples here https://github.com/search?q=repo%3Ascil%2Freliable-debundle%20entryPoint&type=code
you can output some modules into dir or files with meaningfule names, like:
"knownPaths": {
"411": "./banner/js/index.js",
"413": "./cart/js/index.js",
"837": "./categorypage/js/index.js"
}
bug: maybe the output file contains require("..\\..\\412");
which should be replaced into require("../../412");
-
2020.07.16 merge from hectorqin/debundle
-
use
config.moduleAst = ["body", 0, "expression", "argument", "arguments", 0];
for webpack,
instead of["body", 0, "expression", "arguments", 0];
.
file:src/index.js
-
use
recast.types.visit
instead ofrecast.types.traverse
.
file:src/extern/replace-method/index.js
-
v0.5.3.1 support windows os dir style using
path.normalize
. -
v0.5.3.2 able to parse
n.d
torequire.d
-
v0.5.3.3 support
"replaceRequires": "inline",
in the situation SameNameVar -
v0.5.3.4 support
"replaceRequires": "inline,variable",
and configkeepArgumentsDeeperThan
-
v0.5.3.5 support
"fileExt":".js"
.
"1": "tool/str.js"
would saven(1)
astool/str.js
, nottool/str.js/index.js
-
v0.5.3.6 support
"replaceResultString"
. -
v0.5.3.7 support
friendlyExportsFrom
. -
v0.5.3.8 support
friendlyBool
. -
v0.5.3.9 support
reduceComma
. -
v0.5.3.10 support
filters
. used to change produced string. added a new filtersprettier
. -
v0.5.3.11 support
support_nest
.
function (e, t, n) { // n is require.
n(3); // n is require
function x(){
var n =3; // this n is not require
}
}
In old 1egoman/debundle, "replaceRequires": "inline"
would replace all n
with require
in a module function function (e, t ,n)
. How to limit it?
Reliable-debundle not only support inline
or variable
, but also both inline
and variable
which could produce following code:
const n = require;
require('./3');
function x(){
var n =3; // this n is not require
}
function (e, t, n) { // deep: 0
"use strict";
/// n:263
var r;
void 0 === (o = "function" == typeof (r = function () { // deep: 1
}
) ? r.call(t, n, t, e) : r) || (e.exports = o) // n is `require` as a parameter of a level 1 function
!function () { // deep: 1
r = function () { // deep:2
return d
}.call(t, n, t, e) // n is `require`, e is module of parameters of a level 2 function
void 0 === r || (e.exports = r) // e is mudule
}()
}
By default, scil/debundle only replace the parameter n
with level 1 function. To replace n
with level 2 function, set
"keepArgumentsDeeperThan":2,
In old 1egoman/debundle, inline
tends to replace all n
with require
in a module function function (e, t ,n)
. How to limit it?
"keepDeeperThan": 2,
would make debundle ignore everything in functions with level 3 or deeper.
see examples 8.0 and 8.1 in test_scil/bundle
function (e, t, n) { // deep: 0
/// as n(1)
n(0); // this is require
function deep1() { // deep: 1
return function n(param) { // deep: 2
if (param === 0) return 'from the deep2 n, not require n';
return function () { // deep: 3
return n(0) // deep2 n, not require n
}
}
}
var m = deep1()()();
console.log(m);
}
And an extra config "inDescendantsOfSameNameDeclaraton"
When n
is require
, there may be another varable which is also named n
but is not requrie
. This is SameNameVar.
function (e, t, n) { // ★★★ this n is `require`
var x = n(0);
function It(e) {
var n = p(e); // ★★★ this n is not `require`, just a SameNameVar. code: `boolVarHasSameName`
// Prior to v0.5.3.3(official debundle),
// you have to use `"replaceRequires": "variable",`,
// otherwise you got `require(99)` from `n(99)`.
return n && n(99);
}
function b(e, t, n) { // ★★★ this n is not `require`, just a SameNameVar. code: `boolParamHasSameName`
return n(99);
}
function c(){ // deep: 1
function n(){} // ★★★ this n is not `require`, just a SameNameVar. code: `boolDeclarationWithSameName`
}
function deep1() { // deep: 1
return function n(param) { // deep: 2
if (param === 0) return 'from the deep2 n, not `require` ';
return function () { // deep: 3
return n(0) // ★★★ deep2 n, not `require`.
// ★★★ Currently scil/debunble sees it as `require`,
// but adds a extra config `"inDescendantsOfSameNameDeclaraton": "keep",`
// or `"inDescendantsOfSameNameDeclaraton": "ask",`
}
}
}
var m = deep1()()();
}
Related Code:
visitFunction
and
visitVariableDeclaration
in src/extern/replace-method/index.js
Related Test:
3--webpack-SameNameVar-visitVariableDeclaration.js
and 4--webpack-SameNameVar-visitFunction.js
in test_scil/bundle
- https://astexplorer.net/ support multiple parsers
- Esprima parser
- https://github.com/benjamn/recast
- https://github.com/benjamn/ast-types/blob/master/def/core.ts
var recast = require('recast');
var print = recast.print;
print(ast_node)
Reasons vary, but this tool was originally developed to help me with a reverse engineering project. Needless to say, sifting through minified bundles to try and figure out how a service works isn't fun and is a lot easier when that bundle is broken into files and those files have semantic names.
{
"type": "browserify",
"entryPoint": 1,
"knownPaths": {}
}
(To debundle a simple Webpack bundle, replace browserify
the above configuration with webpack
)
A configuration can have a number of flags - they are documented in DOCS.md.
Is debundling lossless? Ie, if I bundle my code then debundle, will I get the same source that was originally bundled?
No. There a bunch of metadata that's lost when bundling:
- Any custom
package.json
settings for eachnode_module
and the root package. - In a webpack bundle, the names of modules aren't in the bundle. By default, debundling will produce
files named after the module id (ie,
1.js
) unless manually overridden. - If your code was minified, the output files from the debundling process will also be minified (ie, no whitespace, single letter variables, etc). It's up to you to run source through other tools to make it look nicer.
- Make sure that either when rebundling or running with node that you're using the correct file as your entrypoint.
- Read through all the configuration options. Some of them have caveats.
- You could have run into an edge case that I haven't seen yet. Feel free to open an issue if you believe that to be the case.
Not officially. However, if a bundle shares the same type module layout as Browserify or Webpack it may be possible to set the moduleAst configuration option to point to the location of the modules.
- After cloning down the project, run
npm install
- that should be it. - Debundler entry point is
./src/index.js
(that's how you run it!) - A bunch of sample bundles are in
test_bundles/
. A script,test_bundles/run_test.sh
can run the debundler against a given bundle and try to debundle it intodist/
. (CI will, as part of running tests, debundle all the bundles in that folder.) - Make sure any contribution pass the tests:
npm test
Some companies specify in their terms of service that their code cannot be "reverse engineered". Debundling can definitely (depending on how you're using the code) fall under that umbrella. Understand what you are doing so you don't break any agreements 😄