Mini Shell
#!/usr/bin/bash
#
# Copyright 2005-2010 Harald Hoyer <harald@redhat.com>
# Copyright 2005-2010 Red Hat, Inc. All rights reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
usage() {
{
echo "Usage: ${0##*/} [options] [<initramfs file> [<filename> [<filename> [...] ]]]"
echo "Usage: ${0##*/} [options] -k <kernel version>"
echo
echo "-h, --help print a help message and exit."
echo "-s, --size sort the contents of the initramfs by size."
echo "-m, --mod list modules."
echo "-f, --file <filename> print the contents of <filename>."
echo "--unpack unpack the initramfs, instead of displaying the contents."
echo " If optional filenames are given, will only unpack specified files,"
echo " else the whole image will be unpacked. Won't unpack anything from early cpio part."
echo "--unpackearly unpack the early microcode part of the initramfs."
echo " Same as --unpack, but only unpack files from early cpio part."
echo "-v, --verbose unpack verbosely."
echo "-k, --kver <kernel version> inspect the initramfs of <kernel version>."
echo
} >&2
}
[[ $dracutbasedir ]] || dracutbasedir=/usr/lib/dracut
sorted=0
modules=0
unset verbose
declare -A filenames
unset POSIXLY_CORRECT
TEMP=$(getopt \
-o "vshmf:k:" \
--long kver: \
--long file: \
--long mod \
--long help \
--long size \
--long unpack \
--long unpackearly \
--long verbose \
-- "$@")
# shellcheck disable=SC2181
if (($? != 0)); then
usage
exit 1
fi
eval set -- "$TEMP"
while (($# > 0)); do
case $1 in
-k | --kver)
KERNEL_VERSION="$2"
shift
;;
-f | --file)
filenames[${2#/}]=1
shift
;;
-s | --size) sorted=1 ;;
-h | --help)
usage
exit 0
;;
-m | --mod) modules=1 ;;
-v | --verbose) verbose="--verbose" ;;
--unpack) unpack=1 ;;
--unpackearly) unpackearly=1 ;;
--)
shift
break
;;
*)
usage
exit 1
;;
esac
shift
done
[[ $KERNEL_VERSION ]] || KERNEL_VERSION="$(uname -r)"
if [[ $1 ]]; then
image="$1"
if ! [[ -f $image ]]; then
{
echo "$image does not exist"
echo
} >&2
usage
exit 1
fi
else
if [[ -d /efi/Default ]] || [[ -d /boot/Default ]] || [[ -d /boot/efi/Default ]]; then
MACHINE_ID="Default"
elif [[ -f /etc/machine-id ]]; then
read -r MACHINE_ID < /etc/machine-id
else
MACHINE_ID="Default"
fi
if [[ -d /efi/loader/entries || -L /efi/loader/entries ]] \
&& [[ $MACHINE_ID ]] \
&& [[ -d /efi/${MACHINE_ID} || -L /efi/${MACHINE_ID} ]]; then
image="/efi/${MACHINE_ID}/${KERNEL_VERSION}/initrd"
elif [[ -d /boot/loader/entries || -L /boot/loader/entries ]] \
&& [[ $MACHINE_ID ]] \
&& [[ -d /boot/${MACHINE_ID} || -L /boot/${MACHINE_ID} ]]; then
image="/boot/${MACHINE_ID}/${KERNEL_VERSION}/initrd"
elif [[ -d /boot/efi/loader/entries || -L /boot/efi/loader/entries ]] \
&& [[ $MACHINE_ID ]] \
&& [[ -d /boot/efi/${MACHINE_ID} || -L /boot/efi/${MACHINE_ID} ]]; then
image="/boot/efi/${MACHINE_ID}/${KERNEL_VERSION}/initrd"
elif [[ -f /lib/modules/${KERNEL_VERSION}/initrd ]]; then
image="/lib/modules/${KERNEL_VERSION}/initrd"
elif [[ -f /boot/initramfs-${KERNEL_VERSION}.img ]]; then
image="/boot/initramfs-${KERNEL_VERSION}.img"
elif [[ -f /usr/lib/modules/${KERNEL_VERSION}/initramfs.img ]]; then
image="/usr/lib/modules/${KERNEL_VERSION}/initramfs.img"
elif [[ $MACHINE_ID ]] \
&& mountpoint -q /efi; then
image="/efi/${MACHINE_ID}/${KERNEL_VERSION}/initrd"
elif [[ $MACHINE_ID ]] \
&& mountpoint -q /boot/efi; then
image="/boot/efi/${MACHINE_ID}/${KERNEL_VERSION}/initrd"
else
image=""
fi
fi
shift
while (($# > 0)); do
filenames[${1#/}]=1
shift
done
if ! [[ -f $image ]]; then
{
echo "No <initramfs file> specified and the default image '$image' cannot be accessed!"
echo
} >&2
usage
exit 1
fi
TMPDIR="$(mktemp -d -t lsinitrd.XXXXXX)"
# shellcheck disable=SC2064
trap "rm -rf '$TMPDIR'" EXIT
dracutlibdirs() {
for d in lib64/dracut lib/dracut usr/lib64/dracut usr/lib/dracut; do
echo "$d/$1"
done
}
extract_files() {
((${#filenames[@]} == 1)) && nofileinfo=1
for f in "${!filenames[@]}"; do
[[ $nofileinfo ]] || echo "initramfs:/$f"
[[ $nofileinfo ]] || echo "========================================================================"
$CAT "$image" 2> /dev/null | cpio --extract --verbose --quiet --to-stdout "$f" 2> /dev/null
((ret += $?))
[[ $nofileinfo ]] || echo "========================================================================"
[[ $nofileinfo ]] || echo
done
}
list_modules() {
echo "dracut modules:"
# shellcheck disable=SC2046
$CAT "$image" | cpio --extract --verbose --quiet --to-stdout -- \
$(dracutlibdirs modules.txt) 2> /dev/null
((ret += $?))
}
list_files() {
echo "========================================================================"
if [ "$sorted" -eq 1 ]; then
$CAT "$image" 2> /dev/null | cpio --extract --verbose --quiet --list | sort -n -k5
else
$CAT "$image" 2> /dev/null | cpio --extract --verbose --quiet --list | sort -k9
fi
((ret += $?))
echo "========================================================================"
}
list_squash_content() {
SQUASH_IMG="squash-root.img"
SQUASH_TMPFILE="$TMPDIR/initrd.root.sqsh"
$CAT "$image" 2> /dev/null | cpio --extract --verbose --quiet --to-stdout -- \
$SQUASH_IMG > "$SQUASH_TMPFILE" 2> /dev/null
if [[ -s $SQUASH_TMPFILE ]]; then
echo "Squashed content ($SQUASH_IMG):"
echo "========================================================================"
unsquashfs -ll "$SQUASH_TMPFILE" | tail -n +4
echo "========================================================================"
fi
}
unpack_files() {
if ((${#filenames[@]} > 0)); then
for f in "${!filenames[@]}"; do
$CAT "$image" 2> /dev/null | cpio -id --quiet $verbose $f
((ret += $?))
done
else
$CAT "$image" 2> /dev/null | cpio -id --quiet $verbose
((ret += $?))
fi
}
read -r -N 2 bin < "$image"
if [ "$bin" = "MZ" ]; then
command -v objcopy > /dev/null || {
echo "Need 'objcopy' to unpack an UEFI executable."
exit 1
}
objcopy \
--dump-section .linux="$TMPDIR/vmlinuz" \
--dump-section .initrd="$TMPDIR/initrd.img" \
--dump-section .cmdline="$TMPDIR/cmdline.txt" \
--dump-section .osrel="$TMPDIR/osrel.txt" \
"$image" /dev/null
uefi="$image"
image="$TMPDIR/initrd.img"
[ -f "$image" ] || exit 1
fi
if ((${#filenames[@]} <= 0)) && [[ -z $unpack ]] && [[ -z $unpackearly ]]; then
if [ -n "$uefi" ]; then
echo -n "initrd in UEFI: $uefi: "
du -h "$image" | while read -r a _ || [ -n "$a" ]; do echo "$a"; done
if [ -f "$TMPDIR/osrel.txt" ]; then
name=$(sed -En '/^PRETTY_NAME/ s/^\w+=["'"'"']?([^"'"'"'$]*)["'"'"']?/\1/p' "$TMPDIR/osrel.txt")
id=$(sed -En '/^ID/ s/^\w+=["'"'"']?([^"'"'"'$]*)["'"'"']?/\1/p' "$TMPDIR/osrel.txt")
build=$(sed -En '/^BUILD_ID/ s/^\w+=["'"'"']?([^"'"'"'$]*)["'"'"']?/\1/p' "$TMPDIR/osrel.txt")
echo "OS Release: $name (${id}-${build})"
fi
if [ -f "$TMPDIR/vmlinuz" ]; then
version=$(strings -n 20 "$TMPDIR/vmlinuz" | sed -En '/[0-9]+\.[0-9]+\.[0-9]+/ { p; q 0 }')
echo "Kernel Version: $version"
fi
if [ -f "$TMPDIR/cmdline.txt" ]; then
echo "Command line:"
sed -En 's/\s+/\n/g; s/\x00/\n/; p' "$TMPDIR/cmdline.txt"
fi
else
echo -n "Image: $image: "
du -h "$image" | while read -r a _ || [ -n "$a" ]; do echo "$a"; done
fi
echo "========================================================================"
fi
read -r -N 6 bin < "$image"
case $bin in
$'\x71\xc7'* | 070701)
CAT="cat --"
is_early=$(cpio --extract --verbose --quiet --to-stdout -- 'early_cpio' < "$image" 2> /dev/null)
# Debian mkinitramfs does not create the file 'early_cpio', so let's check if firmware files exist
[[ "$is_early" ]] || is_early=$(cpio --list --verbose --quiet --to-stdout -- 'kernel/*/microcode/*.bin' < "$image" 2> /dev/null)
if [[ "$is_early" ]]; then
if [[ -n $unpack ]]; then
# should use --unpackearly for early CPIO
:
elif [[ -n $unpackearly ]]; then
unpack_files
elif ((${#filenames[@]} > 0)); then
extract_files
else
echo "Early CPIO image"
list_files
fi
if [[ -d "$dracutbasedir/skipcpio" ]]; then
SKIP="$dracutbasedir/skipcpio/skipcpio"
else
SKIP="$dracutbasedir/skipcpio"
fi
if ! [[ -x $SKIP ]]; then
echo
echo "'$SKIP' not found, cannot display remaining contents!" >&2
echo
exit 0
fi
fi
;;
esac
if [[ $SKIP ]]; then
bin="$($SKIP "$image" | { read -r -N 6 bin && echo "$bin"; })"
else
read -r -N 6 bin < "$image"
fi
case $bin in
$'\x1f\x8b'*)
CAT="zcat --"
;;
BZh*)
CAT="bzcat --"
;;
$'\x71\xc7'* | 070701)
CAT="cat --"
;;
$'\x02\x21'*)
CAT="lz4 -d -c"
;;
$'\x89'LZO$'\0'*)
CAT="lzop -d -c"
;;
$'\x28\xB5\x2F\xFD'*)
CAT="zstd -d -c"
;;
*)
if echo "test" | xz | xzcat --single-stream > /dev/null 2>&1; then
CAT="xzcat --single-stream --"
else
CAT="xzcat --"
fi
;;
esac
skipcpio() {
$SKIP "$@" | $ORIG_CAT
}
if [[ $SKIP ]]; then
ORIG_CAT="$CAT"
CAT=skipcpio
fi
if ((${#filenames[@]} > 1)); then
TMPFILE="$TMPDIR/initrd.cpio"
$CAT "$image" 2> /dev/null > "$TMPFILE"
pre_decompress() {
cat "$TMPFILE"
}
CAT=pre_decompress
fi
ret=0
if [[ -n $unpack ]]; then
unpack_files
elif ((${#filenames[@]} > 0)); then
extract_files
else
# shellcheck disable=SC2046
version=$($CAT "$image" | cpio --extract --verbose --quiet --to-stdout -- \
$(dracutlibdirs 'dracut-*') 2> /dev/null)
((ret += $?))
echo "Version: $version"
echo
if [ "$modules" -eq 1 ]; then
list_modules
echo "========================================================================"
else
echo -n "Arguments: "
# shellcheck disable=SC2046
$CAT "$image" | cpio --extract --verbose --quiet --to-stdout -- \
$(dracutlibdirs build-parameter.txt) 2> /dev/null
echo
list_modules
list_files
list_squash_content
fi
fi
exit "$ret"
Zerion Mini Shell 1.0