explanation

How-it-works.md

@@ -0,0 +1,60 @@
+# How it works
+
+A lot of the behavior is similar to the [client patcher](https://github.com/y9x/client-patcher).
+
+1. Open the Electron Asar archive
+   This file is similar to a zip archive. It contains all the scripts for the client.
+
+   You can find this by opening the folder where the Electron executable can be found. There will be a folder named "resources". Inside of it, you'll find the app.asar.
+
+   Tools that can be used to open the Asar archive are:
+
+   - 7-Zip - [Asar7z](https://www.tc4shell.com/en/7zip/asar/)
+   - [@electron/asar](https://www.npmjs.com/package/@electron/asar)
+
+2. Open package.json and locate the entry point
+   Electron apps are structured like NodeJS libraries. The package file contains a field named "main". This allows NodeJS and Electron to determine the location of the main entry point.
+
+   In the case of Electron, this entry point is executed in the [main process](https://www.electronjs.org/docs/latest/tutorial/process-model#the-main-process).
+
+   The main process is responsible for creating the [BrowserWindow](https://www.electronjs.org/docs/latest/api/browser-window) which has an API for running a script everytime a page loads.
+
+3. Hook BrowserWindow and run our own preload.
+
+   We can use require.cache to overwrite the exports on the `electron` module. By default, Electron freezes the module exports and makes all the descriptors unconfigurable. This can be bypased by overriding the exports on the module itself.
+
+   ```js
+   (() => {
+     "use strict";
+     const { BrowserWindow } = require("electron");
+     const electronModule = require.cache.electron;
+     const electronExports = electronModule.exports;
+
+     const descs = Object.getOwnPropertyDescriptors(electronExports);
+
+     function hooked(options) {
+       const bw = new BrowserWindow(options);
+
+       console.log("Stole the BrowserWindow:", bw, options);
+
+       return bw;
+     }
+
+     descs.BrowserWindow.get = () => {
+       return hooked;
+     };
+
+     const newExports = Object.defineProperties({}, descs);
+
+     Object.defineProperty(electronModule, "exports", {
+       get: () => newExports,
+       configurable: true,
+       enumerable: true,
+     });
+   })();
+   ```
+
+   All we have to do is modify the entry point and add this code before everything else.
+
+4. Change the preload to a custom one and make sure the original is executed
+   The original preload can be accessed via `options.webPreferences.preload`. For the purpose of this, explanation, this part will be omitted.

README.md

@@ -1,7 +1,9 @@
-# Client Injector
+# Electron Injector
 
 A web-based Asar preload injector.
 
+See [how it works](./How-it-works.md)
+
 ## Features
 
 - No .exe