OpenBSD Builder

This project builds the OpenBSD VM image for the cross-platform-actions/action GitHub action. The image contains a standard OpenBSD installation without any man pages or games. It will install the following file sets:

• bsd
• bsd.mp
• bsd.rd
• baseXX.tgz
• compXX.tgz
• xbaseXX.tgz
• xfontXX.tgz
• xservXX.tgz
• xshareXX.tgz

In addition to the above file sets, the following packages are installed as well:

• sudo
• bash
• curl
• rsync

Except for the root user, there's one additional user, runner, which is the user that will be running the commands in the GitHub action. This user is allowed use sudo without a password.

Architectures and Versions

The following architectures and versions are supported:

Version	x86-64	arm64
6.8	✓	✓
6.9	✓	✓
7.1	✓	✓
7.2	✓	✓
7.3	✓	✓
7.4	✓	✓
7.5	✓	✓
7.6	✓	✓

Building Locally

Prerequisite

UEFI firmware

This needs to be located at resources/ovmf.fd. Copy the OVMF.fd for it's install location to resources/ovmf.fd.

• Ubuntu - Install the ovmf package.
• Fedora - Install the edk2-ovmf package.
• macOS - Copy the OVMF.fd file from a Linux machine

Other

• Packer 1.7.1 or later
• QEMU

Building

1. Clone the repository:

   git clone https://github.com/cross-platform-actions/openbsd-builder
   cd openbsd-builder
   

2. Run build.sh to build the image:

   ./build.sh <version> <architecture>
   

   Where <version> and <architecture> are the any of the versions or architectures available in the above table.

   To target a snapshot, override the checksum variable manually by specifying -var checksum=<checksum> at the end when invoking the build.sh script. You can find the appropriate checksum by looking at the SHA256 file for miniroot<version>.img on an OpenBSD mirror.

   ./build.sh <version> <architecture> -var checksum=<checksum>
   

   On non-macOS platforms the display variable needs to be overridden by specifying -var display=gtk or -var display=sdl at the end when invoking the build.sh script:

   ./build.sh <version> <architecture> -var display=gtk
   

The above command will build the VM image and the resulting disk image will be at the path: output/openbsd-6.8-amd64.qcow2.

Additional Information

At startup, the image will look for a second hard drive. If present and it contains a file named keys at the root, it will install this file as the authorized_keys file for the runner user. The disk is expected to be formatted as FAT32. This is used as an alternative to a shared folder between the host and the guest, since this is not supported by the xhyve hypervisor. FAT32 is chosen because it's the only filesystem that is supported by both the host (macOS) and the guest (OpenBSD) out of the box.

The VM needs to be configured with the e1000 network device. The disk needs to be configured with the GPT partitioning scheme. And the VM needs to be configured to use UEFI. All this is required for the VM image to be able to run using the xhyve hypervisor.

The qcow2 format is chosen because unused space doesn't take up any space on disk, it's compressible and easily converts the raw format, used by xhyve.