Skip to content

Instantly share code, notes, and snippets.

@rosegayming
Last active March 16, 2022 11:49
Show Gist options
  • Save rosegayming/b6372e7abd8b51be6cc4efd1606242be to your computer and use it in GitHub Desktop.
Save rosegayming/b6372e7abd8b51be6cc4efd1606242be to your computer and use it in GitHub Desktop.

While Chrome OS can run a linux virtual machine and you can install checkra1n, you cannot use it because you can't give it usb access to your device. In this tutorial, we're going to enable usb booting on your chromebook and then boot into checkn1x, a tiny linux distribution that you can run from a usb drive that has checkra1n and everything it needs to run pre-installed.

Before continuing, make sure you have a usb flash drive that you don't mind erasing as this process WILL WIPE ALL DATA ON THE DRIVE.

Back up your data

Enabling or disabling developer mode will wipe your chromebook. Most things like extensions, apps, docs, slideshows and such are saved to your google drive automatically and aren't saved locally. Anything stored locally however, such as things in the “My files” tab will be gone unless you upload them somewhere else, such as your google drive.

Enable developer mode

This process is the same on nearly all chromebooks but if it doesn't work for you, google “enable developer mode ” and you should find device specific instructions. First, power off your chromebook. Then, press and hold escape and the refresh button(F3) until you see a screen like this saying “Chrome OS is missing or damaged”. Don't worry, this is normal. Press control and D here. You'll see a 2nd screen saying “To turn OS verification OFF, press ENTER”. Press enter here and congratulations, you’ve enabled developer mode. Due to being in developer mode, you’ll see this warning screen at every boot from now. Either press control and D together and it will boot chrome OS normally, or wait a few seconds and it will just boot automatically. The 1st time you boot in developer mode, it will need to do some setup so it will take a while longer than subsequent boots.

Go and setup your chromebook like normal before continuing to the next step.

Making a bootable usb

First, download the checkn1x iso from https://github.com/asineth0/checkn1x/releases. Next, download Chromebook Recovery Utility from the chrome web store and Checkn1x. Most Chromebooks are 64 bit so download the amd64 one. If that doesn't work, get the 32 bit one, i686. This utility is normally used to make Chromebook Recovery drives (hence the name), but we can trick it into flashing whatever OS we want. Change the extension of the file from .iso to .bin so Chromebook Recovery Utility can detect it.

Then, run the utility and click the gear in put the upper right corner.

Click “Use local image” and select the Checkn1x file. Make sure your usb is plugged in and select it on the next screen. Click continue and it will flash the usb with Checkn1x. The usb is done, now we just have to tell the Chromebook to boot it.

Enable usb booting

We now need to run this script to install the required extra software for usb booting. Press control, alt, and t together to open crosh(Chrome OS Shell). Then, type shell then press enter to get a full shell. Now run the following commands.
cd; curl -LO mrchromebox.tech/firmware-util.sh
sudo install -Dt /usr/local/bin -m 755 firmware-util.sh
sudo firmware-util.sh
You’ll now see the following gui.

We want to install RW_LEGACY firmware, so enter 1. Enter Y to default to booting from usb and wait until it finishes. We can now boot Checkn1x.

Boot Checkn1x

Make sure the usb is plugged in then reboot the Chromebook but rather than pressing control and D at the warning screen, press control and L. This will now open the bios. Press escape to select the boot device. It should just be the name of your usb. Wait a few moments and you should see the Checkra1n gui!

Jailbreak!

Just follow the on screen instructions to jailbreak your phone and reboot the Chromebook when finished. Just follow step 5 again when you need to re-jailbreak.

If you have any other issues, comment below or join the r/jailbreak discord server.

@shadoez
Copy link

shadoez commented Nov 12, 2020

after i hit ctrl L and select my usb, nothing happens

@rosegayming
Copy link
Author

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment