Add iOS 16.1+ support on Linux

[hiylx]

Overview

I added iOS 16.1+ support on Linux by using apfs-fuse to process APFS DMGs.
I used an alternative iBoot64Patcher binary from my repo as the one included did not work

Technical Details

Building a statically linked standalone apfs driver for linux which does not have dependencies

iOS 16.1 support was added to linux by first compiling a statically linked apfs-fuse with the following steps

Spin up a docker container for alpine linux
sudo docker run -it -v $(pwd):/workspace alpine:latest /bin/sh

Install dependencies for building

apk update
apk add build-base cmake git zlib-dev zlib-static bzip2-dev bzip2-static attr-dev linux-headers fuse3-dev fuse3-static

Clone repo

git clone https://github.com/sgan81/apfs-fuse.git
cd apfs-fuse
git submodule update --init

Prepare build folder
mkdir build && cd build

Patch to support static linking

sed -i 's/struct stat64/struct stat/g' ../ApfsLib/DeviceLinux.cpp
sed -i 's/fstat64/fstat/g' ../ApfsLib/DeviceLinux.cpp
sed -i 's/pread64/pread/g' ../ApfsLib/DeviceLinux.cpp
find .. -type f \( -name "*.cpp" -o -name "*.h" \) -exec sed -i '1i #include <cstdint>' {} +
find ../3rdparty -type f -name "*.h" -exec sed -i 's/<cstdint>/<stdint.h>/g' {} +

Create statically linked build files
cmake -DCMAKE_EXE_LINKER_FLAGS="-static" -DCMAKE_POLICY_VERSION_MINIMUM=3.5 ..

Build the executable
make

Building a statically linked standalone HFS driver for linux which does not have dependencies

Spin up a docker container for Ubuntu 20.04
sudo docker run -it -v $(pwd):/workspace ubuntu:20.04 /bin/bash

Install dependencies for building
apt-get update && apt-get install -y build-essential clang wget uuid-dev libssl-dev libbsd-dev libblocksruntime-dev

Download fedora HFS tools

wget https://src.fedoraproject.org/repo/pkgs/hfsplus-tools/diskdev_cmds-540.1.linux3.tar.gz/0435afc389b919027b69616ad1b05709/diskdev_cmds-540.1.linux3.tar.gz
tar -xzf diskdev_cmds-540.1.linux3.tar.gz
cd diskdev_cmds-540.1.linux3

Compile

export CFLAGS="-static"
export LDFLAGS="-static"
make CC="clang -static" LDFLAGS="-static"

Note: It might give an error about fsck, we do not care as the only file we need is newfs_hfs

Logic when APFS ramdisk is used

Create mount points

	mkdir -p /tmp/SSHRD_APFS
	mkdir -p /tmp/SSHRD_HFS

Mount APFS ramdisk

	"$oscheck"/apfs-fuse -o allow_other work/ramdisk.dmg /tmp/SSHRD_APFS

Create empty image file of 400 MB for a new HFS ramdisk

	dd if=/dev/zero of=work/ramdisk1.dmg bs=1M count=400

Format the image as HFS+

	"$oscheck"/newfs_hfs -v SSHRD work/ramdisk1.dmg

Mount the newly created HFS image

	mount -o loop work/ramdisk1.dmg /tmp/SSHRD_HFS

Copy over files from the original ramdisk to the new HFS ramdisk

	rsync -a /tmp/SSHRD_APFS/root/ /tmp/SSHRD_HFS/

Extract sshtars to the newly created image

	tar -xf sshtars/ssh.tar -C /tmp/SSHRD_HFS/

Unmounnt both the ramdisks

	umount /tmp/SSHRD_HFS
	umount /tmp/SSHRD_APFS

Delete mount points

	rm -rf /temp/SSHRD_HFS
	rm -rf /temp/SSHRD_APFS