README.md

@@ -12,7 +12,7 @@ On a UEFI system ensure these conditions are met. See [How to prep](#how-to-prep
 
 - One GPT-partitioned disk
 - Arch Linux live CD ISO image sees exactly one partition with partition type code `BF00` ("Solaris root")
-- Arch Linux live CD ISO image sees exactly one partition with partition type code `EF00` ("EFI system partition")
+- Arch Linux live CD ISO image sees exactly one partition with partition type code `EF00` ("EFI System Partition")
 - The `EF00` EFI partition is mountable, in practical terms this usually only means it has a file system.
 - No ZFS zpool exists
 
@@ -21,16 +21,22 @@ On a UEFI system ensure these conditions are met. See [How to prep](#how-to-prep
 If you are instead running a legacy BIOS machine ensure these conditions are met. See [How to prep](#how-to-prep) for details on how to meet these conditions.
 
 - One MBR-partitioned disk
-- Arch Linux live CD ISO image sees exactly one partition with partition type code `BF` ("Solaris root")
+- Arch Linux live CD ISO image sees exactly one partition with partition type code `bf` ("Solaris root")
 - Arch Linux live CD ISO image sees exactly one partition with partition type code `83` ("Linux")
 - The `83` Linux partition is mountable, in practical terms this usually only means it has a file system.
 - No ZFS zpool exists
 
+Neither with a UEFI nor legacy BIOS system are any of these conditions a requirement from ZFSBootMenu. We're just setting requirements to easily identify if you intend to do a UEFI or a legacy BIOS install. Subsequently the script has no logic to detect UEFI or legacy BIOS mode, that's legwork left to the reader :) The Internet seems to agree that a good quick check is to see if your Arch Linux live CD ISO image has directory `/sys/firmware/efi`.
+```
+[ -d /sys/firmware/efi ] && echo 'Likely a UEFI system' || echo 'Probably a legacy BIOS system'
+```
+If you're unsure nothing's stopping you from just giving it a go with a best guess and if that fails you know you guessed wrong.
+
 ## How to prep
 
 ### UEFI
 
-On a blank example disk `/dev/sda` you can fulfill the UEFI requirements (One `EF00` partition with a file system plus one `BF00` partition) for example like so:
+On a blank example disk `/dev/sda` you can fulfill the UEFI requirements (one `EF00` partition with a file system plus one `BF00` partition) for example like so:
 ```
 sgdisk --new '1::+512M' --new '2' --typecode '1:EF00' --typecode '2:BF00' /dev/sda
 mkfs.vfat /dev/sda1
@@ -39,29 +45,27 @@ mkfs.vfat /dev/sda1
 >
 > `--new '2'`: Create partition number `2`. Both field number 2, the start sector, and field number 3, the end sector, are unspecified, there's no field separator `:`. Field number 2 will be the first free sector - in this case right after partition 1 - and field number 3 will be end of disk. Thus partition `2` will fill the remaining free disk space.
 >
-> `--typecode '1:EF00'`: Partition 1 gets partition type code `EF00`, an EFI system partition.
+> `--typecode '1:EF00'`: Partition 1 gets partition type code `EF00`, an EFI System Partition.
 >
 > `--typecode '2:BF00'`: Partition 2 gets partition type code `BF00`, a Solaris root partition.
 
 The result will be something like this at which point you can start the `setup.sh` script, see [How to run this?](#how-to-run-this) below for more details.
 ```
-# lsblk --paths
+# lsblk --paths --output 'NAME,SIZE,FSTYPE,PARTTYPE,PARTTYPENAME,PTTYPE' /dev/sda
-NAME         MAJ:MIN RM   SIZE RO TYPE MOUNTPOINTS
+NAME         SIZE FSTYPE PARTTYPE                             PARTTYPENAME PTTYPE
-/dev/loop0     7:0    0 685.5M  1 loop /run/archiso/airootfs
+/dev/sda      10G                                                          gpt
-/dev/sr0      11:0    1 808.3M  0 rom  /run/archiso/bootmnt
+├─/dev/sda1  512M vfat   c12a7328-f81f-11d2-ba4b-00a0c93ec93b EFI System   gpt
-/dev/sda    202:0    0    10G  0 disk
+└─/dev/sda2  9.5G        6a85cf4d-1dd2-11b2-99a6-080020736631 Solaris root gpt
-├─/dev/sda1 202:1    0   512M  0 part
-└─/dev/sda2 202:2    0   9.5G  0 part
 ```
 
 ### Legacy BIOS
 
-For a legacy BIOS machine you'll be using a master boot record (MBR) on your disk.
+For a legacy BIOS machine you'll be using a Master Boot Record (MBR) on your disk.
 ```
 printf -- '%s\n' 'label: dos' 'start=1MiB, size=512MiB, type=83, bootable' 'start=513MiB, size=+, type=bf' | sfdisk /dev/sda
 mkfs.vfat /dev/sda1
 ```
-> `label: dos`: Create the following partition layout in a master boot record.
+> `label: dos`: Create the following partition layout in a Master Boot Record.
 >
 > `start=1MiB, size=512MiB, type=83, bootable`: Partition 1 begins 1 Mebibyte after disk start and is 512 Mebibyte in size. We're setting its bootable flag and setting partition type code `83` ("Linux").
 >
@@ -76,13 +80,15 @@ NAME         SIZE FSTYPE PARTTYPE PARTTYPENAME PTTYPE
 └─/dev/sda2  9.5G        0xbf     Solaris      dos
 ```
 
-## ZFS dataset layout
+# Partition naming
 
-The script will create a single ZFS zpool `zpool` on the `BF00` partition with dataset child `zpool/root` which itself has one child `zpool/root/archlinux`, that's where Arch Linux gets installed. Parallel to `zpool/root` it'll create `zpool/data` with a `zpool/data/home` child dataset that gets mounted at `/home`.
+Since this script works with UEFI and legacy BIOS mode we'll be addressing both disk layout schemes with umbrella terms for better readability: "The zpool partition" will be GPT `BF00` partition and MBR `bf` partition. You'll parse the text accordingly. "The boot partition" will be GPT `EF00` partition as well as the MBR `83` partition.
 
-The script will use the `EF00` partition to install a ZFSBootMenu EFI executable if `efibootmgr` says that no such `ZFSBootMenu` entry exists. If ZFSBootMenu gets added to the EFI partition it'll become primary boot option.
+# ZFS dataset layout
 
-## How to run this?
+The script will create a single ZFS zpool `zpool` on the zpool partition with dataset child `zpool/root` which itself has one child `zpool/root/archlinux`, that's where Arch Linux gets installed. Parallel to `zpool/root` it'll create `zpool/data` with a `zpool/data/home` child dataset that gets mounted at `/home`.
+
+# How to run this?
 
 - Boot an Arch Linux live CD ISO image
 - Run:
@@ -91,9 +97,9 @@ The script will use the `EF00` partition to install a ZFSBootMenu EFI executable
     ```
     During execution the script will call itself when it changes into its `chroot`, that's why we `export SCRIPT_URL`. Feel free to update `"${SCRIPT_URL}"` with whatever branch or revision you want to use from [quico.space/quico-os-setup/arch-zbm](https://quico.space/quico-os-setup/arch-zbm). Typically `.../branch/main/setup.sh` as shown above is what you want.
 
-### Options
+## Options
 
-#### Compression
+### Compression
 
 By default we create a zpool with ZFS property `compression=on`. If the `lz4_compress` pool feature is active this will by default enable `compression=lz4`. See `man 7 zfsprops` for example in ZFS 2.1.9 for details. See `zpool get feature@lz4_compress <pool>` to check this feature's status on your `<pool>`.
 
@@ -102,7 +108,7 @@ To get a zpool with uncompressed datasets export the shell variable `ARCHZBM_ZFS
 export ARCHZBM_ZFSPROPS_NO_COMPRESSION=yesplease
 ```
 
-#### Encryption
+### Encryption
 
 By default we encrypt the zpool with ZFS property `encryption=on`. In ZFS 2.1.9 this defaults to `encryption=aes-256-gcm`.
 
@@ -111,19 +117,23 @@ To get a zpool with unencrypted datasets export the shell variable `ARCHZBM_ZFSP
 export ARCHZBM_ZFSPROPS_NO_ENCRYPTION=yup
 ```
 
-## Steps
+# Steps
 
 The script takes the following installation steps.
 
 1. Install ZFS tools and kernel module with [github.com/eoli3n/archiso-zfs](https://github.com/eoli3n/archiso-zfs)
-1. Create one ZFS zpool on top of `BF00` partition, encrypted and compressed datasets, password `password`
+1. Create one ZFS zpool on top of zpool partition, encrypted and compressed datasets, password `password`
     1. _See paragraphs [Compression](#compression)/[Encryption](#encryption) to optionally disable properties_
 1. Create dataset for Arch Linux and `/home`
 1. Install Arch Linux into pool
-1. Add ZFSBootMenu to `EF00` partition if it doesn't exist already
+1. Add ZFSBootMenu to boot partition
+1. Configure boot method
+    - Either an EFI image with EFI boot order entries on a UEFI machine
+    - Or Syslinux with `extlinux` for a legacy BIOS computer
+1. Add `pacman` hooks to keep ZFSBootMenu images (and `extlinux`) updated
 1. Exit into Arch Linux live CD ISO image shell for you to `reboot` and frolick
 
-## Flavor choices
+# Flavor choices
 
 We make the following opinionated flavor choices. Feel free to change them to your liking.
 
@@ -135,7 +145,7 @@ We make the following opinionated flavor choices. Feel free to change them to yo
 - Timezone is `Etc/UTC`
     - Check `timedatectl set-timezone <tzdata-zone>`
 
-## Post-run manual steps
+# Post-run manual steps
 
 After installation you're going to want to at least touch these points in your new Arch Linux install:
 
@@ -452,7 +462,13 @@ zpool import zpool -d /dev/disk/by-partuuid -R /mnt -f -N
 zfs load-key -L prompt zpool
 zfs mount zpool/root/archlinux
 zfs mount -a
+
+# UEFI system ...
 mount /dev/sda1 /mnt/efi
+
+# ... or legacy BIOS system
+mount /dev/sda1 /mnt/boot/syslinux
+
 arch-chroot /mnt /bin/bash
 ```
 
@@ -503,7 +519,7 @@ Explanation:
     zpool/root            none        off       no
     zpool/root/archlinux  /mnt        noauto    yes <-- Now mounted
     ```
-- We lastly mount our EFI system partition (ESP), in this example it's living at `/dev/sda1` so adjust this path accordingly.
+- We lastly mount our EFI System Partition (ESP), in this example it's living at `/dev/sda1` so adjust this path accordingly.
 
     ```
     # df -hTP

setup.sh

@@ -18,7 +18,6 @@ exec 3>&1
 
 declare this_script_url
 this_script_url="${SCRIPT_URL:?}"
-postconf_hook="$(dirname "${this_script_url}")"'/zbm_set_new_uefi_boot_entries.sh'
 
 declare zpool_name zfs_arch_dataset_name
 zpool_name='zpool'
@@ -221,7 +220,7 @@ function select_part () {
     if [[ ! "${parts}" ]]; then
         case "${part_type}" in
             efi)
-                part_type_human_readable='EFI system partition (ESP) with partition type code EF00'
+                part_type_human_readable='EFI System Partition (ESP) with partition type code EF00'
                 ;;
             zfs)
                 if [[ "${part_schema}" = 'mbr' ]]; then
@@ -658,25 +657,22 @@ function configure_zfsbootmenu () {
     paru_install 'zfsbootmenu'
 
     if [[ "${part_schema}" = 'gpt' ]]; then
-        mkdir -p '/etc/zfsbootmenu/posthooks.d'
         cat > '/etc/zfsbootmenu/config.yaml' <<EOF
 Global:
   ManageImages: true
   BootMountPoint: /efi
   InitCPIO: true
-  PostHooksDir: /etc/zfsbootmenu/posthooks.d
 Components:
   Enabled: false
 EFI:
   ImageDir: /efi/EFI/ZBM
   Versions: false
   Enabled: true
-  Stub: /etc/zfsbootmenu/stub-loader.d/linuxx64.efi.stub
+  Stub: /usr/share/zfsbootmenu/stubs/linuxx64.efi.stub/linuxx64.efi.stub  # workaround: https://github.com/zbm-dev/zfsbootmenu/discussions/501
 Kernel:
   CommandLine: ro loglevel=0 zbm.import_policy=hostid
   Prefix: vmlinuz
 EOF
-        get_known_good_stub_loader
     else
         configure_syslinux
         cat > '/etc/zfsbootmenu/config.yaml' <<EOF
@@ -701,12 +697,18 @@ EOF
     zfs set org.zfsbootmenu:commandline='rw nowatchdog rd.vconsole.keymap=de-latin1' "${zpool_name}"'/root/'"${zfs_arch_dataset_name}"
 }
 
-function get_known_good_stub_loader () {
+function add_syslinux_pacman_hook () {
-    local known_good_stub_loader local_stub_loader_abs
+    mkdir -p '/opt/git/quico.space/quico-os-setup/zbm-syslinux-pacman-hook/branches/main'
-    known_good_stub_loader='https://github.com/zbm-dev/zfsbootmenu/raw/master/testing/stubs/linuxx64.efi.stub'
+    git -C '/opt/git/quico.space/quico-os-setup/zbm-syslinux-pacman-hook/branches/main' clone 'https://quico.space/quico-os-setup/zbm-syslinux-pacman-hook.git' .
-    local local_stub_loader_abs='/etc/zfsbootmenu/stub-loader.d/linuxx64.efi.stub'
+    chmod +x '/opt/git/quico.space/quico-os-setup/zbm-syslinux-pacman-hook/branches/main/pacman-zbm-syslinux-regen.sh'
-    mkdir -p "$(dirname "${local_stub_loader_abs}")"
+    ln -s '/opt/git/quico.space/quico-os-setup/zbm-syslinux-pacman-hook/branches/main/pacman-zbm-syslinux-regen.sh' '/usr/local/bin/pacman-zbm-syslinux-regen'
-    curl --silent --location "${known_good_stub_loader}" --output "${local_stub_loader_abs}"
+    ln -s '/opt/git/quico.space/quico-os-setup/zbm-syslinux-pacman-hook/branches/main/pacman-zbm-syslinux-regen.hook' '/usr/share/libalpm/hooks/pacman-zbm-syslinux-regen.hook'
+}
+
+function add_zbm_pacman_hook () {
+    mkdir -p '/opt/git/quico.space/quico-os-setup/zbm-regen-pacman-hook/branches/main'
+    git -C '/opt/git/quico.space/quico-os-setup/zbm-regen-pacman-hook/branches/main' clone 'https://quico.space/quico-os-setup/zbm-regen-pacman-hook.git' .
+    ln -s '/opt/git/quico.space/quico-os-setup/zbm-regen-pacman-hook/branches/main/pacman-zbm-image-regen.hook' '/usr/share/libalpm/hooks/pacman-zbm-image-regen.hook'
 }
 
 function get_disks_with_one_efipart () {
@@ -752,6 +754,12 @@ function install_os_in_chroot () {
 
     # Yes, we do this twice so we immediately get a functional backup file
     generate-zbm
+
+    if [[ "${part_schema}" = 'mbr' ]]; then
+        paru_install 'rsync'
+        add_syslinux_pacman_hook
+    fi
+    add_zbm_pacman_hook
 }
 
 function set_root_pw () {
@@ -849,15 +857,8 @@ function set_new_uefi_boot_entries () {
     fi
 }
 
-function insert_zbm_postconf_hook () {
-    #3.9
-    declare postconf_target_abs='/mnt/etc/zfsbootmenu/posthooks.d/'"$(basename "${postconf_hook}")"
-    curl --silent --location "${postconf_hook}" --output "${postconf_target_abs}"
-    chmod +x "${postconf_target_abs}"
-}
-
 function umount_all () {
-    #3.10
+    #3.9
     if [[ "${part_schema}" = 'mbr' ]]; then
         umount '/mnt/boot/syslinux'
     else
@@ -877,9 +878,8 @@ function finalize_os_setup () {
     configure_zfs_mount_gen                     #3.7
     if [[ "${part_schema}" = 'gpt' ]]; then
         set_new_uefi_boot_entries               #3.8
-        insert_zbm_postconf_hook                #3.9
     fi
-    umount_all                                  #3.10
+    umount_all                                  #3.9
 }
 
 function main () {

zbm_set_new_uefi_boot_entries.sh

@@ -1,177 +0,0 @@
-#!/bin/bash
-
-# Whatever comes in on file descriptor (FD) 3 gets redirected to where file
-# descriptor 1 is pointing. File descriptor 1 points to stdout so when we
-# output-redirect something into FD 3 it shows up on stdout. We can use this
-# to produce arbitrary logging output inside a subshell like so:
-#
-# function my_func () {
-#     some_command "${1:?}"
-#     >&3 echo 'A log message'
-# }
-#
-# var="$(my_func arg_1)"
-#
-# Here "${var}" will only capture the output of some_command "${1:?}". It
-# will not capture 'echo' which will instead show up on our stdout/FD 1.
-exec 3>&1
-
-# https://unix.stackexchange.com/a/48550
-set -E
-trap '[ "$?" -ne 77 ] || exit 77' ERR
-
-function get_partitions () {
-    declare partitions_json
-    partitions_json="$(lsblk --output PATH,PARTTYPE --json --tree)" || return 1
-    printf -- '%s' "${partitions_json}"
-    return 0
-}
-
-function get_parts () {
-    local zfs_install_drive
-    declare parttype parts
-    parttype="${1:?}"
-    zfs_install_drive="${2:-}"
-    case "${parttype}" in
-        zfs)
-            parts="$(get_partitions | jq --raw-output '.[][] | select(.children | length > 0) | .children[] | select(.parttype=="6a85cf4d-1dd2-11b2-99a6-080020736631") | .path')" || exit 1
-            ;;
-        efi)
-            parts="$(get_partitions | jq --raw-output '.[][] | select(.children | length > 0) | select(.path=="'"${zfs_install_drive:?}"'") | .children[] | select(.parttype=="c12a7328-f81f-11d2-ba4b-00a0c93ec93b") | .path')" || exit 1
-            ;;
-        *)
-            >&3 printf -- '%s\n' 'Unknown partition type '"'"'"${parttype}"'"'"', exiting ...'
-            exit 77
-            ;;
-    esac
-    printf -- '%s' "${parts}"
-    return 0
-}
-
-function we_have_exactly_one_part () {
-    local parttype parts_list parts_count
-    parttype="${1:?}"
-    parts_list="${2:?}"
-    parts_count="$(wc -l <<<"${parts_list}")"
-    if [[ "$(wc -c <<<"${parts_list}")" -gt '1' ]]; then
-        case "${parts_count}" in
-            0)
-                >&3 printf -- '%s\n' 'No '"${parttype^^}"' partition found. Exiting ...'
-                exit 77
-                ;;
-            1)
-                return 0
-                ;;
-            *)
-                return 1
-                ;;
-        esac
-        >&3 printf -- '%s\n' 'Partition list does not look valid. Cowardly exiting ...'
-        exit 77
-    fi
-}
-
-function select_part () {
-    local parts enriched_parts enriched_parts_count part_number part_type zfs_install_drive
-    declare part
-    part_type="${1:?}" # 'efi' or 'zfs'
-    zfs_install_drive="${2:-}"
-    if [[ "${zfs_install_drive}" ]]; then
-        # This is intended to find correct EFI partition
-        parts="$(get_parts "${part_type}" "${zfs_install_drive}")"
-    else
-        parts="$(get_parts "${part_type}")"
-    fi
-
-    if [[ ! "${parts}" ]]; then
-        case "${part_type}" in
-            efi)
-                part_type_human_readable='EFI system partition (ESP) with partition type code EF00'
-                ;;
-            zfs)
-                part_type_human_readable='ZFS zpool partition with partition type code BF00'
-                ;;
-        esac
-        >&3 printf -- '%s\n' \
-            'It looks as if there is no '"${part_type_human_readable}" \
-            'on any of the disks. Is this a chroot? Exiting ...'
-        exit 77
-    fi
-
-    if we_have_exactly_one_part "${part_type}" "${parts}"; then
-        part="${parts}"
-    else
-        >&3 printf -- '%s\n' 'More than one '"${part_type^^}"' partition to pick for installation. Cowardly exiting ...'
-        exit 77
-    fi
-    printf -- '%s' "${part}"
-    return 0
-}
-
-function get_part_parent () {
-    local child_partition parent_partition
-    child_partition="${1:?}"
-    parent_partition="$(get_partitions | jq --raw-output '.[][] | select(.children | length > 0) | select(.children[].path=="'"${child_partition:?}"'") | .path')"
-    printf -- '%s' "${parent_partition}"
-    return 0
-}
-
-function get_disks_with_one_efipart () {
-    local disks_with_one_efipart
-    # Find disks that have exactly one EFI partition and where that EFI
-    # partition is partition number 1. We expect exactly one disk to meet
-    # these criteria. Anything else and we bail.
-    disks_with_one_efipart="$(lsblk --output PATH,PARTTYPE --json --tree | jq --raw-output '.[][] | select(.children | length > 0) | select( any (.children[]; (.path | test("^[^[:digit:]]+1")) and (.parttype=="c12a7328-f81f-11d2-ba4b-00a0c93ec93b")) and ([select(.children[].parttype=="c12a7328-f81f-11d2-ba4b-00a0c93ec93b")] | length == 1) ) | .path')"
-    if [[ "$(wc -l <<<"${disks_with_one_efipart}")" -eq '1' ]] && [[ "$(wc -c <<<"${disks_with_one_efipart}")" -gt '1' ]]; then
-        printf -- '%s' "${disks_with_one_efipart}"
-        return 0
-    fi
-    return 1
-}
-
-function set_new_uefi_boot_entries () {
-    declare -a uefi_images
-    mapfile -t uefi_images < \
-        <(find '/efi/EFI/ZBM' -type f -iname '*.efi' -print0 | \
-        xargs -0 --no-run-if-empty --max-args '1' stat -c '%Y %n' | \
-        sort -V | \
-        awk '{print $2}')
-    zpool_drive="$(select_part 'zfs')"
-    zfs_parent="$(get_part_parent "${zpool_drive:?}")"
-    efi_drive="${zfs_parent}"
-
-    if efibootmgr | grep -Piq -- 'ZFSBootMenu'; then
-        local -a old_uefi_entries
-        mapfile -t old_uefi_entries < \
-            <(efibootmgr | \
-            grep -Pio -- '(?<=^Boot)[^\*[:space:]]+(?=\*? ZFSBootMenu)')
-        for old_uefi_entry in "${old_uefi_entries[@]}"; do
-            efibootmgr --bootnum "${old_uefi_entry}" --delete-bootnum &>/dev/null && {
-                >&3 printf -- '%s\n' \
-                    'EFI boot entry '"${old_uefi_entry}"' deleted.'
-            }
-        done
-    fi
-
-    if ! efibootmgr | grep -Piq -- 'ZFSBootMenu'; then
-        local efi_disks_list
-        efi_disks_list="$(get_disks_with_one_efipart)"
-        if grep -Piq -- '^'"${efi_drive}"'$' <<<"${efi_disks_list}"; then
-            for uefi_image in "${uefi_images[@]}"; do
-                uefi_image_version="$(basename "${uefi_image%%.EFI}")"
-                uefi_image_inverted="${uefi_image#/efi}"
-                uefi_image_inverted="${uefi_image_inverted//\//\\}"
-                efibootmgr --disk "${efi_drive}" \
-                    --part 1 \
-                    --create \
-                    --label 'ZFSBootMenu '"${uefi_image_version}" \
-                    --loader "${uefi_image_inverted}" &>/dev/null && {
-                        >&3 printf -- '%s\n' \
-                            'EFI boot entry ZFSBootMenu '"${uefi_image_version}"' added.'
-            }
-            done
-        fi
-    fi
-}
-
-set_new_uefi_boot_entries