Verified Commit 729d16b4 authored by nl6720's avatar nl6720
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Move FAT image to a separate partition outside the ISO 9660 file system

Support bios.syslinux.eltorito boot mode without bios.syslinux.mbr.
bios.syslinux.mbr does not work without bios.syslinux.eltorito because -isohybrid-mbr requires the El Torito boot image.

Support uefi-x64.systemd-boot.esp boot mode without uefi-x64.systemd-boot.eltorito and vice versa.
If uefi-x64.systemd-boot.eltorito is used without uefi-x64.systemd-boot.esp, the El Torito boot image will be placed in the ISO 9660 file system as before.
Note that an ISO created with only uefi-x64.systemd-boot.eltorito will still be bootable as a "hard disk" on OVMF. OVMF will boot the El Torito image.

This change has the following effect on the partition tables:

- *.eltorito options add El Torito boot catalog entries. MBR and GPT are not affected.
- uefi-x64.systemd-boot.esp creates a protective MBR partition table and a GPT table that includes a Linux filesystem data partition for the ISO 9660 volume, an EFI system partition and a Microsoft basic data partition that maps the 300 KiB padding added by xorriso.
- bios.syslinux.mbr (without uefi-x64.systemd-boot.esp): adds a MBR partition table and maps the ISO 9660 volume as a partition of type 0x83. No GPT is produced.
- bios.syslinux.mbr (with uefi-x64.systemd-boot.esp): adds an second partition in the MBR (after 0xEE) starting from sector 0 to sector 1 with type 0 and marks it as bootable. This violates the GPT specification, but allows some systems to succesfully boot in BIOS mode from GPT.

Fixes #49
parent 5f4260fc
......@@ -523,9 +523,9 @@ _make_efi() {
_make_boot_on_fat() {
local ucode_image all_ucode_images=()
_msg_info "Preparing kernel and intramfs for the FAT file system..."
mmd -i "${isofs_dir}/EFI/archiso/efiboot.img" \
mmd -i "${work_dir}/efiboot.img" \
"::/${install_dir}" "::/${install_dir}/boot" "::/${install_dir}/boot/${arch}"
mcopy -i "${isofs_dir}/EFI/archiso/efiboot.img" "${airootfs_dir}/boot/vmlinuz-"* \
mcopy -i "${work_dir}/efiboot.img" "${airootfs_dir}/boot/vmlinuz-"* \
"${airootfs_dir}/boot/initramfs-"*".img" "::/${install_dir}/boot/${arch}/"
for ucode_image in \
"${airootfs_dir}/boot/"{intel-uc.img,intel-ucode.img,amd-uc.img,amd-ucode.img,early_ucode.cpio,microcode.cpio}
......@@ -535,7 +535,7 @@ _make_boot_on_fat() {
fi
done
if (( ${#all_ucode_images[@]} )); then
mcopy -i "${isofs_dir}/EFI/archiso/efiboot.img" "${all_ucode_images[@]}" "::/${install_dir}/boot/"
mcopy -i "${work_dir}/efiboot.img" "${all_ucode_images[@]}" "::/${install_dir}/boot/"
fi
_msg_info "Done!"
}
......@@ -544,7 +544,6 @@ _make_boot_on_fat() {
_make_boot_uefi-x64.systemd-boot.esp() {
local efiboot_imgsize="0"
_msg_info "Setting up systemd-boot for UEFI booting..."
install -d -m 0755 -- "${isofs_dir}/EFI/archiso"
# the required image size in KiB (rounded up to the next full MiB with an additional MiB for reserved sectors)
efiboot_imgsize="$(du -bc \
......@@ -561,26 +560,26 @@ _make_boot_uefi-x64.systemd-boot.esp() {
)"
# The FAT image must be created with mkfs.fat not mformat, as some systems have issues with mformat made images:
# https://lists.gnu.org/archive/html/grub-devel/2019-04/msg00099.html
[[ -e "${isofs_dir}/EFI/archiso/efiboot.img" ]] && rm -f -- "${isofs_dir}/EFI/archiso/efiboot.img"
[[ -e "${work_dir}/efiboot.img" ]] && rm -f -- "${work_dir}/efiboot.img"
_msg_info "Creating FAT image of size: ${efiboot_imgsize} KiB..."
mkfs.fat -C -n ARCHISO_EFI "${isofs_dir}/EFI/archiso/efiboot.img" "$efiboot_imgsize"
mkfs.fat -C -n ARCHISO_EFI "${work_dir}/efiboot.img" "$efiboot_imgsize"
mmd -i "${isofs_dir}/EFI/archiso/efiboot.img" ::/EFI ::/EFI/BOOT
mcopy -i "${isofs_dir}/EFI/archiso/efiboot.img" \
mmd -i "${work_dir}/efiboot.img" ::/EFI ::/EFI/BOOT
mcopy -i "${work_dir}/efiboot.img" \
"${airootfs_dir}/usr/lib/systemd/boot/efi/systemd-bootx64.efi" ::/EFI/BOOT/BOOTx64.EFI
mmd -i "${isofs_dir}/EFI/archiso/efiboot.img" ::/loader ::/loader/entries
mcopy -i "${isofs_dir}/EFI/archiso/efiboot.img" "${profile}/efiboot/loader/loader.conf" ::/loader/
mmd -i "${work_dir}/efiboot.img" ::/loader ::/loader/entries
mcopy -i "${work_dir}/efiboot.img" "${profile}/efiboot/loader/loader.conf" ::/loader/
for _conf in "${profile}/efiboot/loader/entries/"*".conf"; do
sed "s|%ARCHISO_LABEL%|${iso_label}|g;
s|%INSTALL_DIR%|${install_dir}|g;
s|%ARCH%|${arch}|g" \
"${_conf}" | mcopy -i "${isofs_dir}/EFI/archiso/efiboot.img" - "::/loader/entries/${_conf##*/}"
"${_conf}" | mcopy -i "${work_dir}/efiboot.img" - "::/loader/entries/${_conf##*/}"
done
# shellx64.efi is picked up automatically when on /
if [[ -e "${airootfs_dir}/usr/share/edk2-shell/x64/Shell_Full.efi" ]]; then
mcopy -i "${isofs_dir}/EFI/archiso/efiboot.img" \
mcopy -i "${work_dir}/efiboot.img" \
"${airootfs_dir}/usr/share/edk2-shell/x64/Shell_Full.efi" ::/shellx64.efi
fi
......@@ -619,29 +618,106 @@ _make_iso() {
if [[ "${quiet}" == "y" ]]; then
xorrisofs_options+=('-quiet')
fi
# xorrisofs options for x86 BIOS booting using SYSLINUX
# shellcheck disable=SC2076
if [[ " ${bootmodes[*]} " =~ ' bios.syslinux.' ]]; then
if [[ ! -f "${isofs_dir}/isolinux/isolinux.bin" ]]; then
_msg_error "The file '${isofs_dir}/isolinux/isolinux.bin' does not exist." 1
fi
if [[ ! -f "${isofs_dir}/isolinux/isohdpfx.bin" ]]; then
_msg_error "The file '${isofs_dir}/isolinux/isohdpfx.bin' does not exist." 1
# SYSLINUX El Torito
if [[ " ${bootmodes[*]} " =~ ' bios.syslinux.eltorito ' ]]; then
if [[ ! -f "${isofs_dir}/isolinux/isolinux.bin" ]]; then
_msg_error "The file '${isofs_dir}/isolinux/isolinux.bin' does not exist." 1
fi
# SYSLINUX MBR
if [[ " ${bootmodes[*]} " =~ ' bios.syslinux.mbr ' ]]; then
if [[ ! -f "${isofs_dir}/isolinux/isohdpfx.bin" ]]; then
_msg_error "The file '${isofs_dir}/isolinux/isohdpfx.bin' does not exist." 1
fi
xorrisofs_options+=(
# SYSLINUX MBR bootstrap code; does not work without "-eltorito-boot isolinux/isolinux.bin"
'-isohybrid-mbr' "${isofs_dir}/isolinux/isohdpfx.bin"
# When GPT is used, create an additional partition in the MBR (besides 0xEE) for sectors 0–1 (MBR
# bootstrap code area) and mark it as bootable
# This violates the UEFI specification, but may allow booting on some systems
# https://wiki.archlinux.org/index.php/Partitioning#Tricking_old_BIOS_into_booting_from_GPT
'--mbr-force-bootable'
# Set the ISO 9660 partition's type to "Linux filesystem data"
# When only MBR is present, the partition type ID will be 0x83 "Linux" as xorriso translates all
# GPT partition type GUIDs except for the ESP GUID to MBR type ID 0x83
'-iso_mbr_part_type' '0FC63DAF-8483-4772-8E79-3D69D8477DE4'
# Move the first partition away from the start of the ISO to match the expectations of partition
# editors
# May allow booting on some systems
# https://dev.lovelyhq.com/libburnia/libisoburn/src/branch/master/doc/partition_offset.wiki
'-partition_offset' '16'
)
fi
xorrisofs_options+=(
# El Torito boot image for x86 BIOS
'-eltorito-boot' 'isolinux/isolinux.bin'
# El Torito boot catalog file
'-eltorito-catalog' 'isolinux/boot.cat'
# Required options to boot with ISOLINUX
'-no-emul-boot' '-boot-load-size' '4' '-boot-info-table'
)
else
_msg_error "Using 'bios.syslinux.mbr' boot mode without 'bios.syslinux.eltorito' is not supported." 1
fi
xorrisofs_options+=(
'-eltorito-boot' 'isolinux/isolinux.bin'
'-eltorito-catalog' 'isolinux/boot.cat'
'-no-emul-boot' '-boot-load-size' '4' '-boot-info-table'
'-isohybrid-mbr' "${isofs_dir}/isolinux/isohdpfx.bin"
)
fi
# xorrisofs options for X64 UEFI booting using systemd-boot
# shellcheck disable=SC2076
if [[ " ${bootmodes[*]} " =~ ' uefi-x64.systemd-boot.' ]]; then
xorrisofs_options+=(
'-eltorito-alt-boot'
'-e' 'EFI/archiso/efiboot.img'
'-no-emul-boot'
'-isohybrid-gpt-basdat'
)
if [[ ! -f "${work_dir}/efiboot.img" ]]; then
_msg_error "The file '${work_dir}/efiboot.img' does not exist." 1
fi
[[ -e "${isofs_dir}/EFI/archiso" ]] && rm -rf -- "${isofs_dir}/EFI/archiso"
# systemd-boot in an attached EFI system partition
if [[ " ${bootmodes[*]} " =~ ' uefi-x64.systemd-boot.esp ' ]]; then
# Move the first partition away from the start of the ISO, otherwise the GPT will not be valid and ISO 9660
# partition will not be mountable
[[ " ${xorrisofs_options[*]} " =~ ' -partition_offset ' ]] || xorrisofs_options+=('-partition_offset' '16')
xorrisofs_options+=(
# Attach efiboot.img as a second partition and set its partition type to "EFI system partition"
'-append_partition' '2' 'C12A7328-F81F-11D2-BA4B-00A0C93EC93B' "${work_dir}/efiboot.img"
# Ensure GPT is used as some systems do not support UEFI booting without it
'-appended_part_as_gpt'
)
# systemd-boot in an attached EFI system partition via El Torito
if [[ " ${bootmodes[*]} " =~ ' uefi-x64.systemd-boot.eltorito ' ]]; then
xorrisofs_options+=(
# Start a new El Torito boot entry for UEFI
'-eltorito-alt-boot'
# Set the second partition as the El Torito UEFI boot image
'-e' '--interval:appended_partition_2:all::'
# Boot image is not emulating floppy or hard disk; required for all known boot loaders
'-no-emul-boot'
)
fi
# systemd-boot in an embedded efiboot.img via El Torito
elif [[ " ${bootmodes[*]} " =~ ' uefi-x64.systemd-boot.eltorito ' ]]; then
# The ISO will not contain a GPT partition table, so to be able to reference efiboot.img, place it as a
# file inside the ISO 9660 file system
install -d -m 0755 -- "${isofs_dir}/EFI/archiso"
cp -a -- "${work_dir}/efiboot.img" "${isofs_dir}/EFI/archiso/efiboot.img"
xorrisofs_options+=(
# Start a new El Torito boot entry for UEFI
'-eltorito-alt-boot'
# Set efiboot.img as the El Torito UEFI boot image
'-e' 'EFI/archiso/efiboot.img'
# Boot image is not emulating floppy or hard disk; required for all known boot loaders
'-no-emul-boot'
)
fi
# Specify where to save the El Torito boot catalog file in case it is not already set by bios.syslinux.eltorito
[[ " ${bootmodes[*]} " =~ ' bios.' ]] || xorrisofs_options+=('-eltorito-catalog' 'EFI/boot.cat')
fi
_msg_info "Creating ISO image..."
......@@ -737,7 +813,7 @@ command_iso() {
bootmodes=('bios.syslinux.mbr' 'bios.syslinux.eltorito')
# If exists, add an EFI "El Torito" boot image (FAT filesystem) to ISO-9660 image.
if [[ -f "${isofs_dir}/EFI/archiso/efiboot.img" ]]; then
if [[ -f "${work_dir}/efiboot.img" ]]; then
bootmodes+=('uefi-x64.systemd-boot.esp' 'uefi-x64.systemd-boot.eltorito')
fi
......
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