Oliver Tzeng olivertzeng

How to downgrade from iOS 15 to iOS 14

The latest SEP/BB as of right now is iOS 15.1, and is partially or fully compatible with iOS 14 depending on your device. See the appropriate section for exact compatibility info.

Prequisites

SHSH blobs for the version you want to downgrade to (e.g. from https://tsssaver.1conan.com/, https://shsh.host/)
macOS or Linux (Ubuntu 20.04 or newer recommended). Windows or a VM will NOT work.

Notes

If the exploit fails even after multiple attempts or your device reboots out of DFU mode, you'll have to start over from the beginning and be quicker next time. (You don't have to redownload anything though.) You may have to force restart your device if it's stuck in DFU.

Arch Linux Installation Guide

Guide to install Arch Linux on an EFI System. Includes these features:

Full Disk Encryption with LUKS
BTRFS with @ and @home subvolumes
Timeshift Backups
Encrypted Swap Partition
rEFInd bootloader
SDDM display manager
KDE Plasma desktop environment

Hi TrollBox user !

You might be here as you saw on Readme or idk where that I were cancelling TrollBox developement. This is true. Before reading this, please excuse my bad english. You probably use TrollBox to unsupervise your device or to use the LocSim. To not disturb any of those activities, I've only archived the repo so you can still use it. But I won't develop anymore on TrollBox, here is why :

Not well organized

The app's structure and code was written by me 1 year ago when I was learning Swift. It's not stable, not clean at all, and is slow.

	Unfortunately I have some bad news for downgrading.
	Before I explain the bad news at the end of this post, I first need to introduce a background of iOS devices.
	In iOS 16, Apple introduced a new firmware component known as Cryptex1. Technically, this is a "virtual" co-processor.
	It's purpose is to allow Apple to push RSRs (Rapid Security Responses) which are separate from traditional iOS updates and can be installed much faster.
	Like other firmwares, it also has a signing ticket locked to a cryptographic nonce (number-used-once).
	We commonly refer to the Apple signing tickets as SHSH blobs.
	Meaning the firmware can't be installed without a valid signing ticket as well as a matching nonce.
	The "big two" components we deal with signing/nonces are AP and SEP. AP is basically the main device chip (Application Processor).
	SEP is the security chip (Secure Enclave Processor).
	With regards to APNonce, Apple conveniently gave us the com.apple.System.boot-nonce NVRAM property which we use to set the APNonce generator.