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repack ubuntu desktop iso with console output
Raw
README.md

repack ubuntu iso without graphical login.

This was useful for me to use remotely. Basically a live server image.

Basically run:

./fix-iso consolify -vv ubuntu-18.04.2.0-desktop-amd64.iso.dist ubuntu-18.04.2.0-desktop-amd64.iso

And then

qemu-system-x86_64 -enable-kvm -device virtio-scsi-pci,id=virtio-scsi-xkvm \
    -object rng-random,filename=/dev/urandom,id=objrng0 \
    -device virtio-rng-pci,rng=objrng0,id=rng0 \
    -device virtio-net-pci,netdev=net00 \
    -netdev type=user,id=net00 \
    -drive file=ubuntu-18.04.2.0-desktop-amd64.iso,id=disk00,if=none,format=raw,index=0 \
    -device virtio-blk,drive=disk00,serial=ubuntu-18.04.2.0-desktop-amd64.iso \
    -snapshot -m 2G
Raw
fix-iso
#!/bin/bash
VERBOSITY=0
unset TEMP_D
TEMP_D=""
error() { echo "$@" 1>&2; }
fail() { local r=$?; [ $r -eq 0 ] && r=1; failrc "$r" "$@"; }
failrc() { local r=$1; shift; [ $# -eq 0 ] || error "$@"; exit $r; }
Usage() {
local ufunc="${1:-main}_Usage"
"$ufunc"
}
bad_Usage() {
Usage "$1" 1>&2;
[ $# -eq 0 ] || shift
[ $# -eq 0 ] || error "$@";
return 1;
}
cleanup() {
[ -z "${TEMP_D}" -o ! -d "${TEMP_D}" ] || rm -Rf "${TEMP_D}"
}
debug() {
local level=${1}; shift;
[ "${level}" -gt "${VERBOSITY}" ] && return
error "${@}"
}
vflag() {
# vflag([change=+0], [base=$VERBOSITY])
# write to stdout the 'vflag' (-v or -vv ..) for expected verbosity.
# vflag(-1, 3) = "-vv"
local myv=$((${2-${VERBOSITY}}${1:-+0}))
[ "$myv" -le "0" ] && return
local flag="-" i=0
while [ $i -lt $myv ] && i=$((i+1)); do
flag="${flag}v"
done
echo "$flag"
}
find_cmd() {
local cmd="$1" found="" p=""
shift
if found=$(command -v "$cmd"); then
echo "$found"
return 0
fi
for p in "$@"; do
[ -x "$p/$cmd" ] && { echo "$p/$cmd"; return 0; }
done
return 1
}
extract_Usage() {
cat <<EOF
Usage: ${0##*/} extract iso_in out_d
Extract the iso to out_d.
EOF
}
extract_iso() {
local iso="$1" out_d="$2"
shift 2
[ -d "$out_d" ] || mkdir -p "$out_d" || {
error "Failed to create dir '$out_d'"
return 1
}
[ -f "$iso" ] || { error "$iso: not a file."; return 1; }
debug 1 "extracting iso $iso to $out_d"
bsdtar "--directory=$out_d" -xf "$iso" "$@" ||
{ error "Failed to extract iso '$iso'"; return 1; }
# needed or cleanup will fail.
find "$out_d/" -type d -exec chmod u+w '{}' \; ||
{ error "Failed to give user write perms."; return 1; }
local out=""
if [ -f "${out_d}/images/efiboot.img" ]; then
debug 1 "creating images/isohdpfx.bin from $iso"
out=$(dd if=$iso bs=432 count=1 of="$out_d/images/isohdpfx.bin" 2>&1) ||
{ error "Failed to isohdpfx.bin from front of $iso"; return 1; }
fi
}
extract_main() {
local short_opts="hv"
local long_opts="help,verbose"
local getopt_out=""
getopt_out=$(getopt --name "${0##*/}" \
--options "${short_opts}" --long "${long_opts}" -- "$@") &&
eval set -- "${getopt_out}" ||
{ bad_Usage get_krd; return; }
local cur="" next="" iso_in="" out_d=""
while [ $# -ne 0 ]; do
cur="$1"; next="$2";
case "$cur" in
-h|--help) Usage extract; exit 0;;
-v|--verbose) VERBOSITY=$((${VERBOSITY}+1));;
--) shift; break;;
esac
shift;
done
[ $# -eq 2 ] || {
bad_Usage extract "Expected 2 args, got $# ($*)"
return;
}
iso_in="$1"
out_d="$2"
[ -f "$iso_in" ] || { bad_Usage extract "$1: not a file"; return; }
[ ! -e "$out_d" -o -d "$out_d" ] || {
bad_Usage extract "$2: exists but is not a directory.";
return;
}
extract_iso "$iso_in" "$out_d" || return
return 0
}
pack_Usage() {
cat <<EOF
Usage: pack [options] iso_dir iso_file
Create iso_file from iso_dir.
EOF
}
cat_isohdpfx() {
# isolinux 3:6.03+dfsg1-2 /usr/lib/ISOLINUX/isohdpfx.bin
base64 --decode <<"EOF"
M+2QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJAz7fqO1bwAfPv8ZjHbZjHJZlNmUQZXjt2O
xVK+AHy/AAa5AAHzpepLBgAAUrRBu6pVMckw9vnNE3IWgftVqnUQg+EBdAtmxwbzBrRC6xXrAjHJ
WlG0CM0TWw+2xkBQg+E/UffhU1JQuwB8uQQAZqGwB+hEAA+CgABmQIDHAuLyZoE+QHz7wHhwdQn6
vOx76kR8AADogwBpc29saW51eC5iaW4gbWlzc2luZyBvciBjb3JydXB0Lg0KZmBmMdJmAwb4e2YT
Fvx7ZlJmUAZTagFqEInmZvc26HvA5AaI4YjFkvY27nuIxgjhQbgBAooW8nvNE41kEGZhw+geAE9w
ZXJhdGluZyBzeXN0ZW0gbG9hZCBlcnJvci4NCl6stA6KPmIEswfNEDwKdfHNGPTr/QAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
EOF
}
pack_iso() {
local isocmd="" iso="$1" in_d="$2" ret=""
[ -d "$in_d" ] || { error "$in_d: not a directory"; return 1; }
assert_tmpdir
local hdpfx="${TEMP_D}/isohdpfx.bin" efiimg="boot/grub/efi.img"
local label="ubuntu-repack"
cat_isohdpfx > "$hdpfx" || { error "Failed writing $hdpfx"; return 1; }
if [ -f "${in_d}/$efiimg" ]; then
isocmd=(
xorriso -as mkisofs
-output "$iso"
-V "$label"
-isohybrid-mbr "${hdpfx}"
-eltorito-catalog isolinux/boot.cat
-eltorito-boot isolinux/isolinux.bin
-no-emul-boot -boot-load-size 4 -boot-info-table
-eltorito-alt-boot
-e "$efiimg" -no-emul-boot -isohybrid-gpt-basdat
"${in_d}"
)
else
isocmd=(
mkisofs
-V "$label" -JR -o "$iso"
-c isolinux/boot.cat -b isolinux/isolinux.bin
-no-emul-boot -boot-load-size 4 -boot-info-table
-joliet-long
"$in_d"
)
fi
local isolinux="$in_d/isolinux/isolinux.bin"
if [ -e "$isolinux" -a ! -w "$isolinux" ]; then
chmod u+w "$isolinux" || {
error "Failed adding write to $isolinux"
return 1
}
fi
debug 2 "creating $iso: ${isocmd[*]}"
[ ! -e "$iso" ] || rm -f "$iso" ||
{ error "Failed to remove existing $iso"; return 1; }
if [ $VERBOSITY -lt 2 ]; then
local out=""
out=$("${isocmd[@]}" 2>&1)
ret=$?
else
"${isocmd[@]}"
ret=$?
fi
[ $ret -eq 0 ] || {
rm -f "$iso"
error "Failed to create iso $iso from $in_d"
return $ret
}
}
pack_main() {
local short_opts="hv"
local long_opts="help,verbose"
local getopt_out=""
getopt_out=$(getopt --name "${0##*/}" \
--options "${short_opts}" --long "${long_opts}" -- "$@") &&
eval set -- "${getopt_out}" ||
{ bad_Usage get_krd; return; }
local cur="" next="" iso_in="" out_d=""
while [ $# -ne 0 ]; do
cur="$1"; next="$2";
case "$cur" in
-h|--help) Usage get_krd; exit 0;;
-v|--verbose) VERBOSITY=$((${VERBOSITY}+1));;
--) shift; break;;
esac
shift;
done
[ $# -eq 2 ] || {
bad_Usage pack "Expected 2 args, got $# ($*)"
return;
}
in_d="$1"
iso="$2"
[ -d "$in_d" ] || {
bad_Usage pack "$1: is not a directory"
return;
}
pack_iso "$iso" "$in_d" || fail
error "Created $iso from $in_d"
return 0
}
dir2squashfs() {
local src_d="$1" out="$2" owner="${3:-$(id -u):$(id -g)}"
local tmpfile ret="" cmd=""
tmpfile="${out}.${0##*/}.$$" || return
cmd=( mksquashfs "$src_d" "$tmpfile" -xattrs -comp xz )
debug 1 "starting: ${cmd[*]}"
"${cmd[@]}"
ret=$?
debug 1 "finished: returned $ret"
if [ $ret -eq 0 ]; then
chown "$owner" "$tmpfile" ||
{ error "failed chown $owner $tmpfile"; return 1; }
mv "$tmpfile" "$out" ||
{ error "failed to move file to $out"; return 1; }
else
rm -f "$tmpfile"
error "mksquashfs failed [$ret]: ${cmd[*]}."
fi
return $ret
}
consolify_Usage() {
cat <<EOF
Usage: ${0##*/} consolify [-v] input.iso output.iso
modify input.iso to disable graphics and other server-like things.
options:
-v | --verbose be more verbose
EOF
}
consolify_main() {
local short_opts="hv"
local long_opts="help,verbose"
local getopt_out=""
getopt_out=$(getopt --name "${0##*/}" \
--options "${short_opts}" --long "${long_opts}" -- "$@") &&
eval set -- "${getopt_out}" ||
{ bad_Usage consolify; return; }
local cur="" next="" iso_in="" iso_out="" mp=""
while [ $# -ne 0 ]; do
cur="$1"; next="$2";
case "$cur" in
-h|--help) Usage consolify; exit 0;;
-v|--verbose) VERBOSITY=$((${VERBOSITY}+1));;
--) shift; break;;
esac
shift;
done
[ $# -ge 2 ] || {
bad_Usage edit "must provide iso_in and iso_out.";
return;
}
iso_in="$1"
iso_out="$2"
shift 2
[ -f "$iso_in" ] || { fail "$iso_in: not a file"; return 1; }
local iso_out_fp=""
iso_out_fp=$(realpath "$iso_out") ||
fail "Failed to get full path to '$iso_out'"
if [ -d "$iso_in" ]; then
debug 1 "using source directory $iso_in"
mp="$iso_in"
else
assert_tmpdir
[ -n "$mp" ] || mp="$TEMP_D/workd"
[ -d "$mp" ] || mkdir -p "$mp" ||
fail "Failed to create dir '$mp'"
fi
debug 1 "iso_in=$iso_in iso_out=$iso_out"
local start_d="$PWD" cmd="" arg=""
cmd=( "$0" consolify-iso $(vflag) "$mp" )
if [ ! -d "$iso_in" ]; then
extract_iso "$iso_in" "$mp" || return
fi
debug 1 "invoking ${cmd[*]} in $PWD"
"${cmd[@]}"
ret=$?
if [ $ret -ne 0 ]; then
debug 1 "cmd returned $ret. Not creating '$iso_out'"
failrc $ret
fi
pack_iso "$iso_out_fp" "$mp" ||
fail "Failed to pack iso."
error "created $iso_out."
}
consolify_iso_main() {
local short_opts="hv"
local long_opts="help,verbose"
local getopt_out=""
getopt_out=$(getopt --name "${0##*/}" \
--options "${short_opts}" --long "${long_opts}" -- "$@") &&
eval set -- "${getopt_out}" ||
{ bad_Usage update_from; return; }
local cur="" next="" atx_d="" iso_in="" iso_out=""
local mp="" changedir=false
while [ $# -ne 0 ]; do
cur="$1"; next="$2";
case "$cur" in
-h|--help) Usage update_from; exit 0;;
-v|--verbose) VERBOSITY=$((${VERBOSITY}+1));;
--) shift; break;;
esac
shift;
done
local iso_d="$1"
local img="$iso_d/casper/filesystem.squashfs"
debug 1 "Fixing default options"
local conparms="console=tty0 console=ttyS0,115200n8"
sed -i "s/quiet splash/$conparms/" \
"$iso_d/isolinux/txt.cfg" "$iso_d/boot/grub/grub.cfg" || {
error "Failed to edit isolinux/txt.cfg or boot/grub/grub.cfg"
return 1;
}
local s_opts="serial --speed=115200; " bgrub="boot/grub/grub.cfg"
s_opts="${s_opts}terminal_input serial console; "
s_opts="${s_opts}terminal_output serial console; "
sed -i "/set timeout=/s/^/$s_opts/" "$iso_d/$bgrub" &&
grep -q "$s_opts" "$iso_d/$bgrub" || {
error "Failed to add serial opts to $bgrub"
return 1
}
debug 1 "Calling mount-image-callback to edit ${img#${iso_d}/}"
sudo mount-image-callback --overlay --system-resolvconf "$img" -- \
"$0" consolify_dir _MOUNTPOINT_ "$img.new" ||
{ error "Failed to consolify $img"; return 1; }
mv --force "$img.new" "$img" ||
{ error "Failed to rename $img.new to $img"; return 1; }
debug 1 "updated $img"
return 0
}
consolify_dir_main() {
local d="$1" out="$2"
chroot "$d" env DEBIAN_FRONTEND=noninteractive sh -exc '
apt-get --purge --assume-yes remove snapd
apt-get update --quiet
apt-get install --no-install-recommends --assume-yes \
openssh-server ssh-import-id \
screen tmux git
rm -f /etc/ssh/ssh_host_*_key
' </dev/null
cat > "$d/lib/systemd/system/ssh-keygen.service" <<"EOF"
[Unit]
Description=OpenSSH Server Key Generation
ConditionPathExists=!/etc/ssh/sshd_not_to_be_run
PartOf=ssh.service
[Service]
ExecStart=/bin/sh -c '\
fails=0; \
for kt in rsa ecdsa ed25519; do \
f="/etc/ssh/ssh_host_"$kt"_key"; \
[ -f "$f" ] && { echo "$kt: $f existed."; continue; }; \
ssh-keygen -t "$kt" -f "$f" -C "" -N "" || \
{ echo "$kt failed"; fails=$((fails+1)); }; \
done; \
exit $fails'
Type=oneshot
RemainAfterExit=yes
[Install]
WantedBy=ssh.service
Alias=sshd.service
EOF
chroot "$d" systemctl set-default -f multi-user.target
chroot "$d" systemctl enable serial-getty@ttyS0.service
chroot "$d" systemctl enable ssh-keygen.service
dir2squashfs "$d" "$2" || return 1
return
}
edit_Usage() {
cat <<EOF
Usage: ${0##*/} edit [ options ] [iso_in|dir] iso_out [cmd [arg1 [.. ]]]
extract iso_in to a temp dir, then execute cmd. Default cmd is \$SHELL.
extraction dir is set in ISO_D variable.
See also '--cd' and '--mountpoint'
If an argument in cmd is ISO_D then it will be replaced with the value.
options:
-m | --mountpoint MP mount the directory to MP rather than a tmpdir.
-C | --cd change directory to ISO_DIR before executing cmd.
EOF
}
assert_tmpdir() {
[ -n "$TEMP_D" ] && return 0
TEMP_D=$(mktemp -d "${TMPDIR:-/tmp}/${0##*/}.XXXXXX") ||
fail "failed to make tempdir"
}
edit_main() {
local short_opts="hCm:Sv"
local long_opts="help,cd,mountpoint:,verbose"
local getopt_out=""
getopt_out=$(getopt --name "${0##*/}" \
--options "${short_opts}" --long "${long_opts}" -- "$@") &&
eval set -- "${getopt_out}" ||
{ bad_Usage edit; return; }
local cur="" next="" iso_in="" iso_out=""
local mp="" changedir=false
while [ $# -ne 0 ]; do
cur="$1"; next="$2";
case "$cur" in
-h|--help) Usage edit; exit 0;;
-C|--cd) changedir=true;;
-m|--mountpoint) mp=$next; shift;;
-v|--verbose) VERBOSITY=$((${VERBOSITY}+1));;
--) shift; break;;
esac
shift;
done
[ $# -ge 2 ] || {
bad_Usage edit "must provide iso_in and iso_out.";
return;
}
iso_in="$1"
iso_out="$2"
shift 2
[ -f "$iso_in" ] || { fail "$iso_in: not a file"; return 1; }
local iso_out_fp=""
iso_out_fp=$(realpath "$iso_out") ||
fail "Failed to get full path to '$iso_out'"
if [ -d "$iso_in" ]; then
debug 1 "using source directory $iso_in"
mp="$iso_in"
else
assert_tmpdir
[ -n "$mp" ] || mp="$TEMP_D/workd"
[ -d "$mp" ] || mkdir -p "$mp" ||
fail "Failed to create dir '$mp'"
fi
local start_d="$PWD" cmd="" arg=""
cmd=( env "ISO_D=$mp" "START_D=$start_d" )
if [ $# -eq 0 ]; then
if [ "${SHELL:-/bin/sh}" = "/bin/bash" ]; then
# norc to not get PS1 overwritten
set -- PS1="[update-${iso_in##*/} \W]$ " bash --norc
else
set -- ${SHELL}
fi
fi
for arg in "$@"; do
if [ "${arg}" = "ISO_D" ]; then
debug 1 "replaced string ISO_D in arguments arg ${#cmd[@]}"
arg="$mp"
fi
cmd[${#cmd[@]}]="$arg"
done
if [ "$mp" != "$iso_in" ]; then
extract_iso "$iso_in" "$mp" || return
fi
${changedir} && cd "$mp"
debug 1 "invoking ${cmd[*]} in $PWD"
"${cmd[@]}"
ret=$?
cd "$start_d"
if [ $ret -ne 0 ]; then
debug 1 "cmd returned $ret. Not creating '$iso_out'"
failrc $ret
fi
pack_iso "$iso_out_fp" "$mp" ||
fail "Failed to pack iso."
error "created $iso_out."
}
main_Usage() {
cat <<EOF
Usage: ${0##*/} [-v|-h] subcmd [args [...]]
Subcommands are:
edit extract, execute comand, re-pack
extract extract the iso to a directory
pack create an ISO from a directory.
consolify get rid of graphics in iso.
EOF
}
main() {
while [ $# -ne 0 ]; do
case "$1" in
-h|--help) Usage main; exit 0;;
-v|--verbose) VERBOSITY=$((VERBOSITY+1)); shift; continue;;
--) shift; break;;
-*|--*) bad_Usage main "$1: not a main argument."; return;;
*) break;;
esac
done
[ $# -gt 0 ] || { bad_Usage main; return; }
local submain="${1//-/_}_main"
type -t "$submain" >/dev/null 2>&1 || {
bad_Usage main "Unknown subcommand '$1'."
return
}
shift
trap cleanup EXIT
"$submain" "$@"
}
main "$@"
# vi: ts=4 expandtab
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