5 releases
0.2.0 | Aug 30, 2024 |
---|---|
0.1.3 | Aug 30, 2024 |
0.1.2 | Aug 23, 2024 |
0.1.1 | Aug 22, 2024 |
0.1.0 | Aug 21, 2024 |
#193 in Filesystem
41 downloads per month
61KB
1.5K
SLoC
buildfs
buildfs
is an easy-to-use CLI tool meant for both manual and automated (CI) use to create raw filesystem (rootfs) images that can be used to boot virtual machines.
It has 4 subcommands: pack
and unpack
to manage packages, dry-run
to test the correctness of a package and run
to actually fully execute the package. A package can be a single TOML build script, a directory with the build script and references to other resources, or such a directory compressed in either a .tar
or a .tar.gz
.
Getting started
cargo install buildfs
.- Root privileges are needed (for
mkfs
andmount/umount
), so ensure you can runsudo
on the target machine and that it is running a Linux distribution. - Insert the following build script contents into
/tmp/build_script.toml
. This is a simple configuration that will make a minified bootable Debian root filesystem from thedocker.io/library/debian:bookworm-slim
image:
[filesystem]
type = "Ext4"
size_mib = 250
[container]
engine = "Docker"
rootful = true
wait_timeout_s = 1
image = { name = "docker.io/library/debian", tag = "bookworm-slim" }
[[commands]]
script_inline = """
#!/bin/bash
apt update
apt install -y udev systemd-sysv iputils-ping curl
rm -f /etc/systemd/system/multi-user.target.wants/systemd-resolved.service
rm -f /etc/systemd/system/dbus-org.freedesktop.resolve1.service
rm -f /etc/systemd/system/sysinit.target.wants/systemd-timesyncd.service
systemctl disable e2scrub_reap.service
rm -vf /etc/systemd/system/timers.target.wants/*
for console in ttyS0; do
mkdir "/etc/systemd/system/serial-getty@$console.service.d/"
cat <<'EOF' > "/etc/systemd/system/serial-getty@$console.service.d/override.conf"
[Service]
# systemd requires this empty ExecStart line to override
ExecStart=
ExecStart=-/sbin/agetty --autologin root -o '-p -- \\u' --keep-baud 115200,38400,9600 %I dumb
EOF
done
passwd -d root
rm -rf /usr/share/{doc,man,info,locale}
cat >> /etc/sysctl.conf <<EOF
# This avoids a SPECTRE vuln
kernel.unprivileged_bpf_disabled=1
EOF
"""
[[overlays]]
source_inline = """
nameserver 8.8.8.8
nameserver 8.8.4.4
nameserver 1.1.1.1
"""
destination = "/etc/resolv.conf"
[export.directories]
include = [ "/bin", "/etc", "/home", "/lib", "/lib64", "/root", "/sbin", "/usr" ]
create = [ "/var/lib/dpkg", "/dev", "/proc", "/sys", "/run", "/tmp", "/var/lib/systemd" ]
- Ensure
~/.cargo/bin
is on your PATH so thatbuildfs
is accessible and ensure Docker is installed (Podman is also supported, just change the value ofengine
in the build script and ensure a Podman Unix socket is bound). - Run
sudo buildfs run -o debian.ext4 /tmp/build_script.toml
and wait until it produces you a ready-to-usedebian.ext4
root filesystem!
Dependencies
~17–30MB
~483K SLoC