#!/usr/bin/python3 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__) parser.add_argument( "output_file", nargs="?", default=pathlib.Path("filesystem.img"), type=pathlib.Path ) parser.add_argument( "--timezone", default="Australia/Melbourne", type=lambda s: s.split("/"), help='NOTE: MUST be "Area/Zone" not e.g. "UTC", for now', ) parser.add_argument( "--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) subprocess.check_call( [ "mmdebstrap", "--mode=unshare", "--variant=apt", '--aptopt=Acquire::http::Proxy "http://apt-cacher-ng.cyber.com.au:3142"', '--aptopt=Acquire::https::Proxy "DIRECT"', "--dpkgopt=force-unsafe-io", "--components=main contrib non-free", # needed for CPU security patches "--include=init initramfs-tools xz-utils live-boot netbase", "--include=dbus", # https://bugs.debian.org/814758 "--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. "--include=zstd", "--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', #'--include=live-task-xfce', # 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 #'--include=xfce4-terminal', # 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 https://bugs.debian.org/981004 # 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/up.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? "--include=msmtp-mta", "--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? "--include=rsyslog-relp", """--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";'""", # https://bugs.debian.org/894444 # 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]' 'WantedBy=multi-user.target'", "--customize-hook=>>$1/lib/systemd/system/apt-daily-upgrade.service printf '%s\n' '[Install]' 'WantedBy=multi-user.target'", # 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 -- https://github.com/systemd/systemd/issues/9714) # 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 twb@cyber.com.au (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", # FIXME: https://bugs.debian.org/603700 "--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. "--dpkgopt=path-exclude=/usr/share/doc/*", "--dpkgopt=path-exclude=/usr/share/info/*", "--dpkgopt=path-exclude=/usr/share/man/*", "--dpkgopt=path-exclude=/usr/share/omf/*", "--dpkgopt=path-exclude=/usr/share/help/*", "--dpkgopt=path-exclude=/usr/share/gnome/help/*", # Configure timezone (not needed to boot)` # FIXME: use live-config instead? "--include=tzdata", 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/up.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', "sid", td / "filesystem.squashfs", ] ) with args.output_file.open("wb") as f: subprocess.check_call( ["rdsquashfs", "--cat=boot/USB/filesystem.img", td / "filesystem.squashfs"], stdout=f, ) subprocess.check_call( [ "mcopy", "-i", f"{args.output_file}@@{esp_offset}", td / "filesystem.squashfs", f"::{live_media_path}/filesystem.squashfs", ] )