| Message ID | 20231107145048.10436-1-andrey.popov@yadro.com |
|---|---|
| State | New |
| Headers | show |
| Series | classes/image-live: Add support for building EFI-bootable ISO images for architectures other than x86 and x86_64 | expand |
This begs the question. Should we drop syslinux usage altogether? It hasn't been maintained for several years, and is unlikely to become maintained again. Alex On Tue, 7 Nov 2023 at 15:51, Andrey Popov <andrey.popov@yadro.com> wrote: > > Since syslinux is only compatible with platforms that use x86-based > CPUs, this change allows creation of bootable ISO images for other > EFI-compatible platforms by replacing invocation of the isohybrid > tool for those platforms with a python script that creates MBR > partition table with a single entry that points to a bootable > EFI image placed inside the ISO image. > > Signed-off-by: Andrey Popov <andrey.popov@yadro.com> > --- > meta/classes-recipe/image-live.bbclass | 129 ++++++++++++++++++++++--- > 1 file changed, 115 insertions(+), 14 deletions(-) > > diff --git a/meta/classes-recipe/image-live.bbclass b/meta/classes-recipe/image-live.bbclass > index 95dd44a..ac7fc1b 100644 > --- a/meta/classes-recipe/image-live.bbclass > +++ b/meta/classes-recipe/image-live.bbclass > @@ -2,15 +2,15 @@ > # > # SPDX-License-Identifier: MIT > > -# Creates a bootable image using syslinux, your kernel and an optional > +# Creates a bootable image using syslinux (for x86), your kernel and an optional > # initrd > > # > # End result is two things: > # > -# 1. A .hddimg file which is an msdos filesystem containing syslinux, a kernel, > -# an initrd and a rootfs image. These can be written to harddisks directly and > -# also booted on USB flash disks (write them there with dd). > +# 1. A .hddimg file which is an msdos filesystem containing syslinux (for x86), > +# a kernel, an initrd and a rootfs image. These can be written to harddisks > +# directly and also booted on USB flash disks (write them there with dd). > # > # 2. A CD .iso image > > @@ -29,8 +29,10 @@ do_bootimg[depends] += "dosfstools-native:do_populate_sysroot \ > mtools-native:do_populate_sysroot \ > cdrtools-native:do_populate_sysroot \ > virtual/kernel:do_deploy \ > - ${MLPREFIX}syslinux:do_populate_sysroot \ > - syslinux-native:do_populate_sysroot \ > + ${@d.getVar('MLPREFIX') + 'syslinux:do_populate_sysroot \ > + syslinux-native:do_populate_sysroot' if __import__('re').match('i.86', d.getVar('TARGET_ARCH')) or \ > + __import__('re').match('x86_64', d.getVar('TARGET_ARCH')) else \ > + 'xorriso-native:do_populate_sysroot'} \ > ${@'%s:do_image_%s' % (d.getVar('PN'), d.getVar('LIVE_ROOTFS_TYPE').replace('-', '_')) if d.getVar('ROOTFS') else ''} \ > " > > @@ -71,14 +73,92 @@ MKISOFS_OPTIONS = "-no-emul-boot -boot-load-size 4 -boot-info-table" > BOOTIMG_VOLUME_ID ?= "boot" > BOOTIMG_EXTRA_SPACE ?= "512" > > +def compute_chs(sector_z): > + C = int(sector_z / (63 * 255)) > + H = int((sector_z % (63 * 255)) / 63) > + # convert zero-based sector to CHS format > + S = int(sector_z % 63) + 1 > + # munge accord to partition table format > + S = (S & 0x3f) | (((C >> 8) & 0x3) << 6) > + C = (C & 0xFF) > + return (C, H, S) > + > +def mk_efi_part_table(iso, start, length): > + from struct import pack > + > + # Compute starting and ending CHS addresses for the partition entry. > + (s_C, s_H, s_S) = compute_chs(start) > + (e_C, e_H, e_S) = compute_chs(start + length - 1) > + > + # Write the 66 byte partition table to bytes 0x1BE through 0x1FF in > + # sector 0 of the .ISO. > + # > + # See the partition table format here: > + # http://en.wikipedia.org/wiki/Master_boot_record#Sector_layout > + f = open(iso, 'r+b') > + f.seek(0x1BE) > + f.write(pack("<8BLL48xH", 0x80, s_H, s_S, s_C, > + 0xEF, e_H, e_S, e_C, start, length, 0xAA55)) > + f.close() > + > +def runtool(cmdln_or_args): > + import subprocess > + > + if isinstance(cmdln_or_args, list): > + cmd = cmdln_or_args[0] > + shell = False > + else: > + import shlex > + cmd = shlex.split(cmdln_or_args)[0] > + shell = True > + > + sout = subprocess.PIPE > + serr = subprocess.STDOUT > + > + try: > + process = subprocess.Popen(cmdln_or_args, stdout=sout, > + stderr=serr, shell=shell) > + sout, serr = process.communicate() > + # combine stdout and stderr, filter None out and decode > + out = ''.join([out.decode('utf-8') for out in [sout, serr] if out]) > + except OSError as err: > + bb.fatal("Cannot run command %s: %s" % (cmd, err)) > + > + return process.returncode, out > + > +def exec_cmd(cmd_and_args): > + args = cmd_and_args.split() > + ret, out = runtool(args) > + out = out.strip() > + if ret != 0: > + bb.fatal("exec_cmd: %s returned '%s' instead of 0\noutput: %s" % \ > + (cmd_and_args, ret, out)) > + return ret, out > + > +def install_efi_part_table(iso_img): > + find_efi_img_cmd = "xorriso -indev %s -find /efi.img \ > + -name efi.img -exec report_lba --" % iso_img > + ret, out = exec_cmd(find_efi_img_cmd) > + efi_img_start = -1 > + efi_img_length = -1 > + for line in out.split("\n"): > + if "File data lba:" in line and "/efi.img" in line: > + file_stat = line[14:].split(',') > + efi_img_start = int(file_stat[1].strip()) * 4 > + efi_img_length = int(int(file_stat[3].strip()) / 512) > + break > + if (efi_img_start < 0) or (efi_img_length < 0): > + bb.fatal("Failed to determine /efi.img attributes") > + mk_efi_part_table(iso_img, efi_img_start, efi_img_length) > + > populate_live() { > - populate_kernel $1 > + populate_kernel $1 > if [ -s "${ROOTFS}" ]; then > install -m 0644 ${ROOTFS} $1/rootfs.img > fi > } > > -build_iso() { > +build_iso_base() { > # Only create an ISO if we have an INITRD and the live or iso image type was selected > if [ -z "${INITRD}" ] || [ "${@bb.utils.contains_any('IMAGE_FSTYPES', 'live iso', '1', '0', d)}" != "1" ]; then > bbnote "ISO image will not be created." > @@ -104,11 +184,13 @@ build_iso() { > fi > > # EFI only > - if [ "${PCBIOS}" != "1" ] && [ "${EFI}" = "1" ] ; then > - # Work around bug in isohybrid where it requires isolinux.bin > - # In the boot catalog, even though it is not used > - mkdir -p ${ISODIR}/${ISOLINUXDIR} > - install -m 0644 ${STAGING_DATADIR}/syslinux/isolinux.bin ${ISODIR}${ISOLINUXDIR} > + if [ -n "$(echo ${TARGET_ARCH} | grep -e i.86)" ] || [ "${TARGET_ARCH}" = "x86_64" ]; then > + if [ "${PCBIOS}" != "1" ] && [ "${EFI}" = "1" ]; then > + # Work around bug in isohybrid where it requires isolinux.bin > + # In the boot catalog, even though it is not used > + mkdir -p ${ISODIR}/${ISOLINUXDIR} > + install -m 0644 ${STAGING_DATADIR}/syslinux/isolinux.bin ${ISODIR}${ISOLINUXDIR} > + fi > fi > > # We used to have support for zisofs; this is a relic of that > @@ -128,7 +210,15 @@ build_iso() { > fi > fi > > - if [ "${PCBIOS}" = "1" ] && [ "${EFI}" != "1" ] ; then > + if [ -z "$(echo ${TARGET_ARCH} | grep -e i.86)" ] && [ "${TARGET_ARCH}" != "x86_64" ]; then > + mkisofs -A ${BOOTIMG_VOLUME_ID} -V ${BOOTIMG_VOLUME_ID} \ > + -o ${IMGDEPLOYDIR}/${IMAGE_NAME}.iso \ > + $mkisofs_compress_opts $mkisofs_iso_level \ > + ${ISODIR} > + return > + fi > + > + if [ "${PCBIOS}" = "1" ] && [ "${EFI}" != "1" ]; then > # PCBIOS only media > mkisofs -V ${BOOTIMG_VOLUME_ID} \ > -o ${IMGDEPLOYDIR}/${IMAGE_NAME}.iso \ > @@ -150,6 +240,17 @@ build_iso() { > isohybrid $isohybrid_args ${IMGDEPLOYDIR}/${IMAGE_NAME}.iso > } > > +python build_iso() { > + import re > + > + bb.build.exec_func("build_iso_base", d) > + target_arch = d.getVar("TARGET_ARCH") > + if not re.match("i.86", target_arch) and not re.match("x86_64", target_arch) \ > + and d.getVar("EFI") == "1": > + install_efi_part_table(d.getVar("IMGDEPLOYDIR") + "/" + \ > + d.getVar("IMAGE_NAME") + ".iso") > +} > + > build_fat_img() { > FATSOURCEDIR=$1 > FATIMG=$2 > -- > 2.34.1 > > > -=-=-=-=-=-=-=-=-=-=-=- > Links: You receive all messages sent to this group. > View/Reply Online (#190285): https://lists.openembedded.org/g/openembedded-core/message/190285 > Mute This Topic: https://lists.openembedded.org/mt/102443878/1686489 > Group Owner: openembedded-core+owner@lists.openembedded.org > Unsubscribe: https://lists.openembedded.org/g/openembedded-core/unsub [alex.kanavin@gmail.com] > -=-=-=-=-=-=-=-=-=-=-=- >
Hello, Alex! I created this patch in hope that I could ensure compatibility with legacy platforms that use BIOS, that is why I kept the syslinux part. I don't think it is a good idea to drop syslinux usage entirely, IMHO. Best regards, Andrey.
diff --git a/meta/classes-recipe/image-live.bbclass b/meta/classes-recipe/image-live.bbclass index 95dd44a..ac7fc1b 100644 --- a/meta/classes-recipe/image-live.bbclass +++ b/meta/classes-recipe/image-live.bbclass @@ -2,15 +2,15 @@ # # SPDX-License-Identifier: MIT -# Creates a bootable image using syslinux, your kernel and an optional +# Creates a bootable image using syslinux (for x86), your kernel and an optional # initrd # # End result is two things: # -# 1. A .hddimg file which is an msdos filesystem containing syslinux, a kernel, -# an initrd and a rootfs image. These can be written to harddisks directly and -# also booted on USB flash disks (write them there with dd). +# 1. A .hddimg file which is an msdos filesystem containing syslinux (for x86), +# a kernel, an initrd and a rootfs image. These can be written to harddisks +# directly and also booted on USB flash disks (write them there with dd). # # 2. A CD .iso image @@ -29,8 +29,10 @@ do_bootimg[depends] += "dosfstools-native:do_populate_sysroot \ mtools-native:do_populate_sysroot \ cdrtools-native:do_populate_sysroot \ virtual/kernel:do_deploy \ - ${MLPREFIX}syslinux:do_populate_sysroot \ - syslinux-native:do_populate_sysroot \ + ${@d.getVar('MLPREFIX') + 'syslinux:do_populate_sysroot \ + syslinux-native:do_populate_sysroot' if __import__('re').match('i.86', d.getVar('TARGET_ARCH')) or \ + __import__('re').match('x86_64', d.getVar('TARGET_ARCH')) else \ + 'xorriso-native:do_populate_sysroot'} \ ${@'%s:do_image_%s' % (d.getVar('PN'), d.getVar('LIVE_ROOTFS_TYPE').replace('-', '_')) if d.getVar('ROOTFS') else ''} \ " @@ -71,14 +73,92 @@ MKISOFS_OPTIONS = "-no-emul-boot -boot-load-size 4 -boot-info-table" BOOTIMG_VOLUME_ID ?= "boot" BOOTIMG_EXTRA_SPACE ?= "512" +def compute_chs(sector_z): + C = int(sector_z / (63 * 255)) + H = int((sector_z % (63 * 255)) / 63) + # convert zero-based sector to CHS format + S = int(sector_z % 63) + 1 + # munge accord to partition table format + S = (S & 0x3f) | (((C >> 8) & 0x3) << 6) + C = (C & 0xFF) + return (C, H, S) + +def mk_efi_part_table(iso, start, length): + from struct import pack + + # Compute starting and ending CHS addresses for the partition entry. + (s_C, s_H, s_S) = compute_chs(start) + (e_C, e_H, e_S) = compute_chs(start + length - 1) + + # Write the 66 byte partition table to bytes 0x1BE through 0x1FF in + # sector 0 of the .ISO. + # + # See the partition table format here: + # http://en.wikipedia.org/wiki/Master_boot_record#Sector_layout + f = open(iso, 'r+b') + f.seek(0x1BE) + f.write(pack("<8BLL48xH", 0x80, s_H, s_S, s_C, + 0xEF, e_H, e_S, e_C, start, length, 0xAA55)) + f.close() + +def runtool(cmdln_or_args): + import subprocess + + if isinstance(cmdln_or_args, list): + cmd = cmdln_or_args[0] + shell = False + else: + import shlex + cmd = shlex.split(cmdln_or_args)[0] + shell = True + + sout = subprocess.PIPE + serr = subprocess.STDOUT + + try: + process = subprocess.Popen(cmdln_or_args, stdout=sout, + stderr=serr, shell=shell) + sout, serr = process.communicate() + # combine stdout and stderr, filter None out and decode + out = ''.join([out.decode('utf-8') for out in [sout, serr] if out]) + except OSError as err: + bb.fatal("Cannot run command %s: %s" % (cmd, err)) + + return process.returncode, out + +def exec_cmd(cmd_and_args): + args = cmd_and_args.split() + ret, out = runtool(args) + out = out.strip() + if ret != 0: + bb.fatal("exec_cmd: %s returned '%s' instead of 0\noutput: %s" % \ + (cmd_and_args, ret, out)) + return ret, out + +def install_efi_part_table(iso_img): + find_efi_img_cmd = "xorriso -indev %s -find /efi.img \ + -name efi.img -exec report_lba --" % iso_img + ret, out = exec_cmd(find_efi_img_cmd) + efi_img_start = -1 + efi_img_length = -1 + for line in out.split("\n"): + if "File data lba:" in line and "/efi.img" in line: + file_stat = line[14:].split(',') + efi_img_start = int(file_stat[1].strip()) * 4 + efi_img_length = int(int(file_stat[3].strip()) / 512) + break + if (efi_img_start < 0) or (efi_img_length < 0): + bb.fatal("Failed to determine /efi.img attributes") + mk_efi_part_table(iso_img, efi_img_start, efi_img_length) + populate_live() { - populate_kernel $1 + populate_kernel $1 if [ -s "${ROOTFS}" ]; then install -m 0644 ${ROOTFS} $1/rootfs.img fi } -build_iso() { +build_iso_base() { # Only create an ISO if we have an INITRD and the live or iso image type was selected if [ -z "${INITRD}" ] || [ "${@bb.utils.contains_any('IMAGE_FSTYPES', 'live iso', '1', '0', d)}" != "1" ]; then bbnote "ISO image will not be created." @@ -104,11 +184,13 @@ build_iso() { fi # EFI only - if [ "${PCBIOS}" != "1" ] && [ "${EFI}" = "1" ] ; then - # Work around bug in isohybrid where it requires isolinux.bin - # In the boot catalog, even though it is not used - mkdir -p ${ISODIR}/${ISOLINUXDIR} - install -m 0644 ${STAGING_DATADIR}/syslinux/isolinux.bin ${ISODIR}${ISOLINUXDIR} + if [ -n "$(echo ${TARGET_ARCH} | grep -e i.86)" ] || [ "${TARGET_ARCH}" = "x86_64" ]; then + if [ "${PCBIOS}" != "1" ] && [ "${EFI}" = "1" ]; then + # Work around bug in isohybrid where it requires isolinux.bin + # In the boot catalog, even though it is not used + mkdir -p ${ISODIR}/${ISOLINUXDIR} + install -m 0644 ${STAGING_DATADIR}/syslinux/isolinux.bin ${ISODIR}${ISOLINUXDIR} + fi fi # We used to have support for zisofs; this is a relic of that @@ -128,7 +210,15 @@ build_iso() { fi fi - if [ "${PCBIOS}" = "1" ] && [ "${EFI}" != "1" ] ; then + if [ -z "$(echo ${TARGET_ARCH} | grep -e i.86)" ] && [ "${TARGET_ARCH}" != "x86_64" ]; then + mkisofs -A ${BOOTIMG_VOLUME_ID} -V ${BOOTIMG_VOLUME_ID} \ + -o ${IMGDEPLOYDIR}/${IMAGE_NAME}.iso \ + $mkisofs_compress_opts $mkisofs_iso_level \ + ${ISODIR} + return + fi + + if [ "${PCBIOS}" = "1" ] && [ "${EFI}" != "1" ]; then # PCBIOS only media mkisofs -V ${BOOTIMG_VOLUME_ID} \ -o ${IMGDEPLOYDIR}/${IMAGE_NAME}.iso \ @@ -150,6 +240,17 @@ build_iso() { isohybrid $isohybrid_args ${IMGDEPLOYDIR}/${IMAGE_NAME}.iso } +python build_iso() { + import re + + bb.build.exec_func("build_iso_base", d) + target_arch = d.getVar("TARGET_ARCH") + if not re.match("i.86", target_arch) and not re.match("x86_64", target_arch) \ + and d.getVar("EFI") == "1": + install_efi_part_table(d.getVar("IMGDEPLOYDIR") + "/" + \ + d.getVar("IMAGE_NAME") + ".iso") +} + build_fat_img() { FATSOURCEDIR=$1 FATIMG=$2
Since syslinux is only compatible with platforms that use x86-based CPUs, this change allows creation of bootable ISO images for other EFI-compatible platforms by replacing invocation of the isohybrid tool for those platforms with a python script that creates MBR partition table with a single entry that points to a bootable EFI image placed inside the ISO image. Signed-off-by: Andrey Popov <andrey.popov@yadro.com> --- meta/classes-recipe/image-live.bbclass | 129 ++++++++++++++++++++++--- 1 file changed, 115 insertions(+), 14 deletions(-)