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import argparse
import pathlib
import subprocess
import tempfile
import pathlib
__author__ = "Trent W. Buck"
__copyright__ = "Copyright © 2020 Trent W. Buck"
__license__ = "expat"
__doc__ = """ build a Debian Live image that can install Debian 11 on ZFS 2
This uses mmdebstrap to do the heavy lifting;
it can run entirely without root privileges.
It emits a USB key disk image that contains a bootable EFI ESP,
which in turn includes a bootloader (refind), kernel, ramdisk, and filesystem.squashfs.
parser = argparse.ArgumentParser(description=__doc__)
"output_file", nargs="?", default=pathlib.Path("filesystem.img"), type=pathlib.Path
type=lambda s: s.split("/"),
help='NOTE: MUST be "Area/Zone" not e.g. "UTC", for now',
"--locale", default="en_AU.UTF-8", help='NOTE: MUST end in ".UTF-8", for now'
args = parser.parse_args()
filesystem_img_size = "512M" # big enough to include filesystem.squashfs + about 64M of bootloader, kernel, and ramdisk.
esp_offset = 1024 * 1024 # 1MiB
esp_label = "UEFI-ESP" # max 8 bytes for FAT32
live_media_path = "debian-live"
with tempfile.TemporaryDirectory(prefix="debian-sid-zfs.") as td:
td = pathlib.Path(td)
'--aptopt=Acquire::http::Proxy ""',
'--aptopt=Acquire::https::Proxy "DIRECT"',
"--components=main contrib non-free", # needed for CPU security patches
"--include=init initramfs-tools xz-utils live-boot netbase",
"--include=dbus", #
"--include=linux-image-amd64 firmware-linux",
# Have ZFS 2.0 support.
"--include=zfs-dkms zfsutils-linux zfs-zed build-essential linux-headers-amd64", # ZFS 2 support
# Make the initrd a little smaller (41MB -> 20MB), at the expensive of significantly slower image build time.
"--essential-hook=mkdir -p $1/etc/initramfs-tools/conf.d",
"--essential-hook=>$1/etc/initramfs-tools/conf.d/zstd echo COMPRESS=zstd",
# Be the equivalent of Debian Live GNOME
# '--include=live-task-gnome',
# FIXME: enable this? It makes live-task-xfce go from 1G to 16G... so no.
#'--aptopt=Apt::Install-Recommends "true"',
# ...cherry-pick instead
# UPDATE: debian-installer-launcher DOES NOT WORK because we don't load crap SPECIFICALLY into /live/installer, in the ESP.
# UPDATE: network-manager-gnome DOES NOT WORK, nor is systemd-networkd auto-started... WTF?
# end result is no networking.
#'--include=live-config user-setup sudo firmware-linux haveged',
#'--include=calamares-settings-debian udisks2', # 300MB weirdo Qt GUI debian installer
# x86_64 CPUs are undocumented proprietary RISC chips that EMULATE a documented x86_64 CISC ISA.
# The emulator is called "microcode", and is full of security vulnerabilities.
# Make sure security patches for microcode for *ALL* CPUs are included.
# By default, it tries to auto-detect the running CPU, so only patches the CPU of the build server.
"--include=intel-microcode amd64-microcode iucode-tool",
"--essential-hook=>$1/etc/default/intel-microcode echo IUCODE_TOOL_INITRAMFS=yes IUCODE_TOOL_SCANCPUS=no",
"--essential-hook=>$1/etc/default/amd64-microcode echo AMD64UCODE_INITRAMFS=yes",
"--dpkgopt=force-confold", # Work around
# DHCP/DNS/SNTP clients...
# FIXME: use live-config ?
"--include=libnss-resolve libnss-myhostname systemd-timesyncd",
"--customize-hook=chroot $1 cp -alf /lib/systemd/resolv.conf /etc/resolv.conf", # This probably needs to happen LAST
# FIXME: fix resolv.conf to point to resolved, not "copy from the build-time OS"
# FIXME: fix hostname & hosts to not exist, not "copy from the build-time OS"
"--customize-hook=systemctl --root=$1 enable systemd-networkd systemd-timesyncd", # is this needed?
# Run a DHCP client on *ALL* ifaces.
# Consider network "up" (start sshd and local login prompt) when *ANY* (not ALL) ifaces are up.
"--customize-hook=>$1/etc/systemd/network/ printf '%s\n' '[Match]' Name='en*' '[Network]' DHCP=yes", # try DHCP on all ethernet ifaces
"--customize-hook=mkdir $1/etc/systemd/system/systemd-networkd-wait-online.service.d",
"--customize-hook=>$1/etc/systemd/system/systemd-networkd-wait-online.service.d/any-not-all.conf printf '%s\n' '[Service]' 'ExecStart=' 'ExecStart=/lib/systemd/systemd-networkd-wait-online --any'",
# Hope there's a central smarthost SMTP server called "mail" in the local search domain.
# FIXME: can live-config do this?
"--customize-hook=>$1/etc/msmtprc printf '%s\n' 'account default' 'syslog LOG_MAIL' 'host mail' 'auto_from on'",
# Hope there's a central RELP logserver called "logserv" in the local domain.
# FIXME: can live-config do this?
"""--customize-hook=>$1/etc/rsyslog.conf printf '%s\n' 'module(load="imuxsock")' 'module(load="imklog")' 'module(load="omrelp")' 'action(type="omrelp" target="logserv" port="2514" template="RSYSLOG_SyslogProtocol23Format")'""",
# Run self-tests on all discoverable hard disks, and (try to) email if something goes wrong.
"--include=smartmontools bsd-mailx",
"--customize-hook=>$1/etc/smartd.conf echo 'DEVICESCAN -n standby,15 -a -o on -S on -s (S/../../7/00|L/../01/./01) -t -H -m root -M once'",
# For rarely-updated, rarely-rebooted SOEs, apply what security updates we can into transient tmpfs COW.
# This CANNOT apply kernel security updates (though it will download them).
# This CANNOT make the upgrades persistent across reboots (they re-download each boot).
# FIXME: Would it be cleaner to set Environment=NEEDRESTART_MODE=a in
# apt-daily-upgrade.service and/or
# unattended-upgrades.service, so
# needrestart is noninteractive only when apt is noninteractive?
"--include=unattended-upgrades needrestart",
"--customize-hook=echo 'unattended-upgrades unattended-upgrades/enable_auto_updates boolean true' | chroot $1 debconf-set-selections",
"""--customize-hook=>$1/etc/needrestart/conf.d/unattended-needrestart.conf echo '$nrconf{restart} = "a";'""", #
# Do an apt update & apt upgrade at boot time (as well as @daily).
# The lack of /etc/machine-id causes these to be implicitly enabled.
# FIXME: use dropin in /etc.
"--customize-hook=>>$1/lib/systemd/system/apt-daily.service printf '%s\n' '[Install]' ''",
"--customize-hook=>>$1/lib/systemd/system/apt-daily-upgrade.service printf '%s\n' '[Install]' ''",
# FIXME: add support for this stuff (for the non-live final install this happens via ansible):
# unattended-upgrades
# smartd
# networkd (boot off ANY NIC, not EVERY NIC --
# refind (bootloader config)
# misc safety nets
# double-check that mmdebstrap's machine-id support works properly
# Bare minimum to let me SSH in.
# FIXME: make this configurable.
# FIXME: trust a CA certificate instead -- see Zero Trust SSH, Jeremy Stott, LCA 2020 <>
# WARNING: tinysshd does not support RSA, nor MaxStartups, nor sftp (unless you also install openssh-client, which is huge).
# FIXME: double-check no host keys are baked into the image (openssh-server and dropbear do this).
"--include=tinysshd rsync",
"--essential-hook=install -dm700 $1/root/.ssh",
'--essential-hook=echo "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIIapAZ0E0353DaY6xBnasvu/DOvdWdKQ6RQURwq4l6Wu (Trent W. Buck)" >$1/root/.ssh/authorized_keys',
# Bare minimum to let me log in locally.
# DO NOT use this on production builds!
"--essential-hook=chroot $1 passwd --delete root",
# Configure language (not needed to boot).
# Racism saves a **LOT** of space -- something like 2GB for Debian Live images.
# FIXME: use live-config instead?
"--include=locales localepurge",
f"--essential-hook=echo locales locales/default_environment_locale select {args.locale} | chroot $1 debconf-set-selections",
f"--essential-hook=echo locales locales/locales_to_be_generated multiselect {args.locale} UTF-8 | chroot $1 debconf-set-selections",
"--customize-hook=chroot $1 sed -i /etc/locale.nopurge -e 's/^USE_DPKG/#ARGH#&/'",
"--customize-hook=chroot $1 localepurge",
"--customize-hook=chroot $1 sed -i /etc/locale.nopurge -e 's/^#ARGH#//'",
# Removing documentation also saves a LOT of space.
# Configure timezone (not needed to boot)`
# FIXME: use live-config instead?
f"--essential-hook=echo tzdata tzdata/Areas select {args.timezone[0]} | chroot $1 debconf-set-selections",
f"--essential-hook=echo tzdata tzdata/Zones/{args.timezone[0]} select {args.timezone[1]} | chroot $1 debconf-set-selections",
# Do the **BARE MINIMUM** to make a USB key that can boot on X86_64 UEFI.
# We use mtools so we do not ever need root privileges.
# We can't use mkfs.vfat, as that needs kpartx or losetup (i.e. root).
# We can't use mkfs.udf, as that needs mount (i.e. root).
# We can't use "refind-install --usedefault" as that runs mount(8) (i.e. root).
# We don't use genisoimage because
# 1) ISO9660 must die;
# 2) incomplete UDF 1.5+ support;
# 3) resulting filesystem can't be tweaked after flashing (e.g. debian-live/site.dir/etc/systemd/network/
# We use refind because 1) I hate grub; and 2) I like refind.
# If you want aarch64 or ia32 you need to install their BOOTxxx.EFI files.
# If you want kernel+initrd on something other than FAT, you need refind/drivers_xxx/xxx_xxx.EFI.
# FIXME: with qemu in UEFI mode (OVMF), I get dumped into startup.nsh (UEFI REPL).
# From there, I can manually type in "FS0:\EFI\BOOT\BOOTX64.EFI" to start refind, tho.
# So WTF is its problem? Does it not support fallback bootloader?
"--include=refind parted mtools",
"--essential-hook=echo refind refind/install_to_esp boolean false | chroot $1 debconf-set-selections",
"--customize-hook=echo refind refind/install_to_esp boolean true | chroot $1 debconf-set-selections",
"--customize-hook=chroot $1 mkdir -p /boot/USB /boot/EFI/BOOT",
"--customize-hook=chroot $1 cp /usr/share/refind/refind/refind_x64.efi /boot/EFI/BOOT/BOOTX64.EFI",
"--customize-hook=chroot $1 cp /usr/share/refind/refind/refind.conf-sample /boot/EFI/BOOT/refind.conf",
f"--customize-hook=chroot $1 truncate --size={filesystem_img_size} /boot/USB/filesystem.img",
f"--customize-hook=chroot $1 parted --script --align=optimal /boot/USB/filesystem.img mklabel gpt mkpart {esp_label} {esp_offset}b 100% set 1 esp on",
f"--customize-hook=chroot $1 mformat -i /boot/USB/filesystem.img@@{esp_offset} -F -v {esp_label}",
f"--customize-hook=chroot $1 mmd -i /boot/USB/filesystem.img@@{esp_offset} ::{live_media_path}",
f"""--customize-hook=echo '"Boot with default options" "boot=live live-media-path={live_media_path}"' >$1/boot/refind_linux.conf""",
f"""--customize-hook=chroot $1 find /boot/ -xdev -mindepth 1 -maxdepth 1 -not -name filesystem.img -not -name USB -exec mcopy -vsbpm -i /boot/USB/filesystem.img@@{esp_offset} {{}} :: ';'""",
# FIXME: copy-out doesn't handle sparseness, so is REALLY slow (about 50 seconds).
# Therefore instead leave it in the squashfs, and extract it later.
# f'--customize-hook=copy-out /boot/USB/filesystem.img /tmp/',
# f'--customize-hook=chroot $1 rm /boot/USB/filesystem.img',
td / "filesystem.squashfs",
with"wb") as f:
["rdsquashfs", "--cat=boot/USB/filesystem.img", td / "filesystem.squashfs"],
td / "filesystem.squashfs",