PyBoot

Script for tether booting Checkm8 vulnerable iOS devices by Matty (moski)

DISCLAIMER

MACOS ONLY - Don't ask for Windows support

Don't use this on a main device, expect issues, bugs and other problems that will make this a bad experience. In saying that, it should work without any major issues, but I'd rather have this disclaimer so I have an excuse to ignore wen eta kids.

What is PyBoot?

PyBoot is a simple alternative to ra1nsn0w for tether booting Checkm8 vulnerable iOS devices. It downloads and patches iBSS/iBEC, downloads the Kernel, DeviceTree and TrustCache for the downgraded version, patches the type to the restore type (E.G krnl -> rkrn, etc) and signs them with SHSH, then sends the images to the device and boots them! PyBoot also doesn't rely on keys being available on theiphonewiki, if there are no keys online then it will place your device into PWNDFU mode and retrieve them automatically!

PyBoot is most likely extremely broken, expect issues and bugs. I just made this for fun, and to have an alternative to ra1nsn0w for booting tethered downgraded devices with SuccessionDown (my Succession fork for tethered downgrades on-device).

How do I tether downgrade my device you might be asking? Simply add my repo (matthewpierson.github.io) to Cydia/Zebra/Sileo and install "SuccessionDown" =)

Feel free to create a pull request if you want to help improve this, or create an issue if you find one!

If you wish to donate to me, feel free to do so, but donations are in no way required or expected. My paypal account is matthewpierson01@gmail.com (I can't create a paypal.me link in New Zealand sadly, so you'd need to send donations manually). I make these things for fun and to be useful to the jailbreak community, not for profit, but money is still nice =)

Current device support

iPhone 5s
iPhone 6/6+
iPhone 6s/6s+
iPhone SE (First Gen)

Semi-Supported Devices -

iPhone 7/7+
iPhone 8/8+
iPhone X

A10/A11 devices may have some issues once booted, support is tentative currently

All iPads and iPods are untested, but they should work fine with the corresponding iPhone CPU. Please try and let me know if they work or not.

Usage

Usage: ./pyboot.py [OPTIONS]

E.G "./pyboot.py -i iPhone8,1 13.2.3 -b ~/Downloads/bootlogo.png"

Options:

  -i, --ios DEVICE IOS      Device model and downgraded iOS version to boot
  -q, --ipsw IPSW DEVICE        Path to downloaded IPSW
  -b, --bootlogo LOGO       Path to .PNG to use as boot logo
  -p, --pwn                 Enter PWNDFU mode, which will also apply sig patches
  -d, --dualboot PARTITION      Name of system partition you wish to boot (e.g disk0s1s3 or disk0s1s6)
  -a, --bootargs        Custom boot-args, will prompt user to enter, don't enter a value upon running PyBoot (Default is '-v')
  -c, --credits         Show credits
  -v, --version         List the version of PyBoot
  --debug           Add 'serial=3' to boot-args to enable the usage of serial cables for debugging
  --amfi            Apply AMFI patches to kernel

Instructions

cd into the PyBoot directory
Run pip3 install -r requirements.txt
Connect your device in DFU mode to your computer
Run PyBoot with your desiered options - E.G './pyboot.py -i iPhone8,1 13.1.1 -b ~/Downloads/customBootLogo.png'
Run PyBoot whenever you want to boot the device
Enjoy!

Known Issues

Very high storage usage after downgrading. Can be partially mitigated with a "Reset content and settings" (mobile_obliterator is called after the downgrade by successiondown but sometimes it doesn't run) You could also try this but I haven't tested this so you'd be on your own.
Some IPSW's won't download from Apple's servers. Can be avoided by either picking a different iOS version or by providing an IPSW
Jailbreak's don't work after downgrading. No current method to jailbreak devices downgraded by this method. Checkra1n will give OTA error when installing Cydia (Might be possible to fix) and Unc0ver fails when attempting to find kernel offsets (Probably can't fix) Unc0ver 4.1.0 and higher should work fine for jailbreaking 13.x - 13.3, you still can't use Checkra1n however as that will cause broken WiFi on boot, plus other issues. Electra does work for jailbreaking 11.x, but has some issues that you can fix by following this tweet from coolstar after jailbreaking. 12.x jailbreaks are untested, will edit README with info later.

Help, PyBoot is giving me errors!

First make sure you have ran "pip3 install -r requirements.txt" before doing anything
If you are getting irecovery or img4tool related errors, download this bash script and run it