OSX-KVM

Note

This README documents the new method to install macOS. The older README is
available here.

This new method does not require an existing physical/virtual macOS
installation. However, this new method requires internet access during the
macOS installation process. This limitation may be addressed in a future
commit.

Note: All blobs and resources included in this repository are re-derivable (all
instructions are included!).

Note: Checkout ideas.md. This project can always use your help,
time and attention.

Requirements

• A modern Linux distribution. E.g. Ubuntu 18.04 LTS 64-bit.

• QEMU > 2.11.1

• A CPU with Intel VT-x / AMD SVM support is required

• A CPU with SSE4.1 support is required for macOS Sierra

• A CPU with AVX2 support is required for macOS Mojave

Note: Older AMD CPU(s) are known to be problematic. AMD FX-8350 works but
Phenom II X3 720 does not. Ryzen processors work just fine.

Installation Preparation

• KVM may need the following tweak on the host machine to work.

  # echo 1 > /sys/module/kvm/parameters/ignore_msrs
  

  To make this change permanent, you may use the following command.

  $ sudo cp kvm.conf /etc/modprobe.d/kvm.conf
  

• Install QEMU and other packages.

  sudo apt-get install qemu uml-utilities virt-manager dmg2img git wget libguestfs-tools
  

  This step may need to be adapted for your Linux distribution.

• Clone this repository on your QEMU system. Files from this repository are
  used in the following steps.

  cd ~
  
  git clone https://github.com/kholia/OSX-KVM.git
  
  cd OSX-KVM
  

• Fetch macOS installer.

  ./fetch-macOS.py
  

  You can choose your desired macOS version here. After executing this step,
  you should have the BaseSystem.dmg file in the current folder.

  Sample run:

  $ ./fetch-macOS.py
  #    ProductID    Version    Build   Post Date  Title
  1    041-47723    10.14.4  18E2034  2019-03-25  macOS Mojave
  2    091-95155    10.13.6    17G66  2019-01-08  macOS High Sierra
  3    041-64745    10.14.5   18F203  2019-05-22  macOS Mojave
  4    041-59913    10.14.5   18F132  2019-05-13  macOS Mojave
  5    041-71284      10.15  19A471t  2019-06-03  macOS 10.15 Beta
  
  Choose a product to download (1-5): 5
  

  Attention: Modern NVIDIA GPUs are supported on HighSierra but not on Mojave
  (yet).

  Next, convert this file into a usable format.

  dmg2img BaseSystem.dmg BaseSystem.img
  

  Note: You can also use the following command to do this conversion, if your
  QEMU version is >= 4.0.0.

  qemu-img convert BaseSystem.dmg -O raw BaseSystem.img
  

• Create a virtual HDD image where macOS will be installed. If you change the
  name of the disk image from mac_hdd.img to something else, the boot scripts
  will need updating to point to the new image name.

  qemu-img create -f qcow2 mac_hdd_ng.img 128G
  

• Setup quick networking by running the following commands.

  sudo ip tuntap add dev tap0 mode tap
  sudo ip link set tap0 up promisc on
  sudo ip link set dev virbr0 up
  sudo ip link set dev tap0 master virbr0
  

  Note: If virbr0 network interface is not present on your system, it may
  have been deactivated. Try enabling it by using the following commands,

  virsh net-start default
  
  virsh net-autostart default
  

• Now you are ready to install macOS ?

Installation

• CLI method (primary). Just run the boot-macOS-NG.sh script to start the
  installation proces.

  ./boot-macOS-NG.sh
  

  If you are new to installing macOS, see the older README for
  help.

  For macOS Catalina, use boot-macOS-Catalina.sh script.

• GUI method (alternate - functional but needs further debugging work).

  • Edit macOS-libvirt-NG.xml file and change the various file paths (search
    for CHANGEME strings in that file). The following command should do the
    trick usually.

    sed -i "s/CHANGEME/$USER/g" macOS-libvirt-NG.xml
    

  • Create a VM by running the following command.

    virsh --connect qemu:///system define macOS-libvirt-NG.xml
    

  • Launch virt-manager, start the macOS virtual machine and install macOS
    as usual.

    Note: You may need to run sudo ip link delete tap0 command before
    virt-manager is able to start the macOS VM.

    Note: You may need to remove the following block from macOS-libvirt-NG.xml
    and run virsh --connect ... again. Alternate easier fix: Remove SATA Disk 3 from the macOS virtual machine in virt-manager.

    <disk type='file' device='disk'>
    <driver name='qemu' type='raw' cache='writeback'/>
      <source file='/home/CHANGEME/OSX-KVM/BaseSystem.img'/>
      <target dev='sdc' bus='sata'/>
      <boot order='3'/>
      <address type='drive' controller='0' bus='0' target='0' unit='2'/>
    </disk>
    

Post-Installation

• See networking notes to setup guest networking.

  I have the following commands present in /etc/rc.local.

  #!/bin/bash
  
  sudo ip tuntap add dev tap0 mode tap
  sudo ip link set tap0 up promisc on
  sudo ip link set dev virbr0 up
  sudo ip link set dev tap0 master virbr0
  

  This has been enough for me so far.

• To get sound on your virtual Mac, see the "Virtual Sound Device" in notes.

• To passthrough GPUs and other devices, see these notes.

• Need a different resolution? Check out the notes included in this
  repository.

Is This Legal?

The "secret" Apple OSK string is widely available on the Internet. It is also included in a public court document available here. I am not a lawyer but it seems that Apple's attempt(s) to get the OSK string treated as a trade secret did not work out. Due to these reasons, the OSK string is freely included in this repository.

Gabriel Somlo also has some thoughts on the legal aspects involved in running macOS under QEMU/KVM.

Motivation

My aim is to enable macOS based builds + testing, kernel debugging, reversing
and security tasks in an easy, reproducible manner without needing to invest in
Apple's closed ecosystem (too heavily).

Backstory: I was a (poor) student in Canada once and Apple made my work on
cracking Apple Keychains a lot
harder than it needed to be.

References

• https://github.com/foxlet/macOS-Simple-KVM

• http://www.contrib.andrew.cmu.edu/~somlo/OSXKVM/

• https://www.kraxel.org/blog/2017/09/running-macos-as-guest-in-kvm/