diff options
Diffstat (limited to '')
| -rwxr-xr-x | mkinitramfs | 523 | ||||
| -rw-r--r-- | mkinitramfs.8 | 153 |
2 files changed, 676 insertions, 0 deletions
diff --git a/mkinitramfs b/mkinitramfs new file mode 100755 index 0000000..40e0fd1 --- /dev/null +++ b/mkinitramfs @@ -0,0 +1,523 @@ +#!/bin/sh + +umask 0022 +export PATH='/usr/bin:/sbin:/bin' + +# Defaults +keep="n" +CONFDIR="/etc/initramfs-tools" +verbose="n" +# Will be updated by busybox's conf hook, if present +BUSYBOXDIR= +export BUSYBOXDIR + +usage() +{ + cat << EOF + +Usage: mkinitramfs [option]... -o outfile [version] + +Options: + -c compress Override COMPRESS setting in initramfs.conf. + -d confdir Specify an alternative configuration directory. + -l level Override COMPRESSLEVEL setting in initramfs.conf. + -k Keep temporary directory used to make the image. + -o outfile Write to outfile. + -r root Override ROOT setting in initramfs.conf. + +See mkinitramfs(8) for further details. + +EOF +} + +usage_error() +{ + usage >&2 + exit 2 +} + +OPTIONS=$(getopt -o c:d:hl:ko:r:v --long help -n "$0" -- "$@") || usage_error + +eval set -- "$OPTIONS" + +while true; do + case "$1" in + -c) + compress="$2" + shift 2 + ;; + -d) + CONFDIR="$2" + shift 2 + if [ ! -d "${CONFDIR}" ]; then + echo "${0}: ${CONFDIR}: Not a directory" >&2 + exit 1 + fi + ;; + -h|--help) + usage + exit 0 + ;; + -l) + compresslevel="$2" + shift 2 + ;; + -o) + outfile="$2" + shift 2 + ;; + -k) + keep="y" + shift + ;; + -r) + ROOT="$2" + shift 2 + ;; + -v) + verbose="y" + shift + ;; + --) + shift + break + ;; + *) + echo "Internal error!" >&2 + exit 1 + ;; + esac +done + +# For dependency ordered mkinitramfs hook scripts. +. /usr/share/initramfs-tools/scripts/functions +. /usr/share/initramfs-tools/hook-functions + +. "${CONFDIR}/initramfs.conf" + +EXTRA_CONF='' +maybe_add_conf() { + if [ -e "$1" ] && \ + basename "$1" \ + | grep '^[[:alnum:]][[:alnum:]\._-]*$' \ + | grep -qv '\.dpkg-.*$'; then + if [ -d "$1" ]; then + echo "W: $1 is a directory instead of file" >&2 + else + EXTRA_CONF="${EXTRA_CONF} $1" + . "$1" + fi + fi +} +for i in /usr/share/initramfs-tools/conf.d/*; do + # Configuration files in /etc mask those in /usr/share + if ! [ -e "${CONFDIR}"/conf.d/"$(basename "${i}")" ]; then + maybe_add_conf "${i}" + fi +done +for i in "${CONFDIR}"/conf.d/*; do + maybe_add_conf "${i}" +done + +# source package confs +for i in /usr/share/initramfs-tools/conf-hooks.d/*; do + if [ -d "${i}" ]; then + echo "W: ${i} is a directory instead of file." >&2 + elif [ -e "${i}" ]; then + . "${i}" + fi +done + +# Check busybox dependency +if [ "${BUSYBOX}" = "y" ] && [ -z "${BUSYBOXDIR}" ]; then + echo >&2 "E: @BUSYBOX_PACKAGES@ is required but not installed" + exit 1 +fi + +if [ -n "${UMASK:-}" ]; then + umask "${UMASK}" +fi + +if [ -z "${outfile}" ]; then + usage_error +fi + +touch "$outfile" +outfile="$(readlink -f "$outfile")" + +# And by "version" we really mean path to kernel modules +# This is braindead, and exists to preserve the interface with mkinitrd +if [ ${#} -ne 1 ]; then + version="$(uname -r)" +else + version="${1}" +fi + +case "${version}" in +/lib/modules/*/[!/]*) + ;; +/lib/modules/[!/]*) + version="${version#/lib/modules/}" + version="${version%%/*}" + ;; +esac + +case "${version}" in +*/*) + echo "$PROG: ${version} is not a valid kernel version" >&2 + exit 2 + ;; +esac + +if [ -z "${compress:-}" ]; then + compress=${COMPRESS?} +fi +unset COMPRESS + +if ! command -v "${compress}" >/dev/null 2>&1; then + echo "W: No ${compress} in ${PATH}, using gzip" >&2 + compress=gzip +fi + +# Support packages installing in /lib/ rather than /boot/ +kconfig="/lib/modules/${version}/config-${version}" +if [ ! -f "$kconfig" ]; then + kconfig="/boot/config-${version}" +fi + +# Check that kernel supports selected compressor, and fall back to gzip. +# Exit if even gzip is not supported. +case "${compress}" in +gzip) kconfig_sym=CONFIG_RD_GZIP ;; +bzip2) kconfig_sym=CONFIG_RD_BZIP2 ;; +lzma) kconfig_sym=CONFIG_RD_LZMA ;; +xz) kconfig_sym=CONFIG_RD_XZ ;; +lzop) kconfig_sym=CONFIG_RD_LZO ;; +lz4) kconfig_sym=CONFIG_RD_LZ4 ;; +zstd) kconfig_sym=CONFIG_RD_ZSTD ;; +esac +if [ -e "${kconfig}" ]; then + while ! grep -q "^$kconfig_sym=y" "${kconfig}"; do + if [ "${compress}" = gzip ]; then + echo "E: gzip compression ($kconfig_sym) not supported by kernel" >&2 + exit 1 + fi + echo "W: ${compress} compression ($kconfig_sym) not supported by kernel, using gzip" >&2 + compress=gzip + kconfig_sym=CONFIG_RD_GZIP + done +else + echo "W: Kernel configuration ${kconfig} is missing, ${compress} compression" \ + "support ($kconfig_sym) cannot be checked and is assumed to be available" >&2 +fi + +if [ -z "${compresslevel:-}" ]; then + compresslevel=${COMPRESSLEVEL:-} +fi +case "${compress}" in +lz4) compresslevel="-${compresslevel:-9}" ;; +zstd) compresslevel="-${compresslevel:-9}" ;; +#gzip|xz|bzip2|lzma|lzop included +*) + # We're not using a compression level by default + compresslevel="${compresslevel:+-${compresslevel}}" + ;; +esac +unset COMPRESSLEVEL + +case "${compress}" in +gzip) # If we're doing a reproducible build, use gzip -n + if [ -n "${SOURCE_DATE_EPOCH}" ]; then + compress="gzip -n" + # Otherwise, substitute pigz if it's available + elif command -v pigz >/dev/null; then + compress=pigz + fi + if [ -n "${compresslevel}" ]; then + compress="${compress} ${compresslevel}" + fi + ;; +lz4) compress="lz4 ${compresslevel} -l" ;; +zstd) compress="zstd -q ${compresslevel}" + # If we're not doing a reproducible build, enable multithreading + test -z "${SOURCE_DATE_EPOCH}" && compress="$compress -T0" + ;; +xz) compress="xz ${compresslevel} --check=crc32" + # If we're not doing a reproducible build, enable multithreading + test -z "${SOURCE_DATE_EPOCH}" && compress="$compress --threads=0" + ;; +bzip2|lzma|lzop) + compress="${compress} ${compresslevel}" + ;; +*) echo "W: Unknown compression command ${compress}" >&2 ;; +esac + +if [ -d "${outfile}" ]; then + echo "${outfile} is a directory" >&2 + exit 1 +fi + +MODULESDIR="/lib/modules/${version}" + +if [ ! -e "${MODULESDIR}" ]; then + echo "W: missing ${MODULESDIR}" >&2 + echo "W: Ensure all necessary drivers are built into the linux image!" >&2 +fi +if [ ! -e "${MODULESDIR}/modules.dep" ]; then + depmod "${version}" +fi + +# Prepare to clean up temporary files on exit +DESTDIR= +__TMPCPIOGZ= +__TMPMAINCPIO= +__TMPEARLYCPIO= +__MODULES_TO_ADD= +# shellcheck disable=SC2317 +clean_on_exit() { + if [ "${keep}" = "y" ]; then + echo "Working files in ${DESTDIR:-<not yet created>}," \ + "early initramfs in ${__TMPEARLYCPIO:-<not yet created>}," \ + "main initramfs in ${__TMPMAINCPIO:-<not yet created>} and" \ + "overlay in ${__TMPCPIOGZ:-<not yet created>}" + else + for path in "${DESTDIR}" "${__TMPCPIOGZ}" "${__TMPMAINCPIO}" "${__TMPEARLYCPIO}" "${__MODULES_TO_ADD}"; do + test -z "${path}" || rm -rf "${path}" + done + fi +} +trap clean_on_exit EXIT +trap "exit 1" INT TERM # makes the EXIT trap effective even when killed + +# Create temporary directory and files for initramfs contents +[ -n "${TMPDIR}" ] && [ ! -w "${TMPDIR}" ] && unset TMPDIR +DESTDIR="$(mktemp -d "${TMPDIR:-/var/tmp}/mkinitramfs_XXXXXX")" || exit 1 +chmod 755 "${DESTDIR}" +__TMPCPIOGZ="$(mktemp "${TMPDIR:-/var/tmp}/mkinitramfs-OL_XXXXXX")" || exit 1 +__TMPMAINCPIO="$(mktemp "${TMPDIR:-/var/tmp}/mkinitramfs-MAIN_XXXXXX")" || exit 1 +__TMPEARLYCPIO="$(mktemp "${TMPDIR:-/var/tmp}/mkinitramfs-FW_XXXXXX")" || exit 1 +__MODULES_TO_ADD="$(mktemp "${TMPDIR:-/var/tmp}/modules_XXXXXX")" || exit 1 + +DPKG_ARCH=$(dpkg --print-architecture) + +# Export environment for hook scripts. +# +export MODULESDIR +export version +export CONFDIR +export DESTDIR +export DPKG_ARCH +export verbose +export KEYMAP +export MODULES +export BUSYBOX +export RESUME +export FSTYPE + +# Private, used by 'catenate_cpiogz'. +export __TMPCPIOGZ + +# Private, used by 'prepend_earlyinitramfs'. +export __TMPEARLYCPIO + +# Private, used by 'manual_add_modules'. +export __MODULES_TO_ADD + +# Create usr-merged filesystem layout, to avoid duplicates if the host +# filesystem is usr-merged. +for d in /bin /lib* /sbin; do + mkdir -p "${DESTDIR}/usr${d}" + ln -s "usr${d}" "${DESTDIR}${d}" +done +for d in conf/conf.d etc run scripts ${MODULESDIR}; do + mkdir -p "${DESTDIR}/${d}" +done + +# Copy in modules.builtin, modules.builtin.modinfo and modules.order (not generated by depmod) +# and modules.builtin.bin (generated by depmod, but too late to avoid +# error messages as in #948257) +for x in modules.builtin modules.builtin.bin modules.builtin.modinfo modules.order; do + if [ -f "${MODULESDIR}/${x}" ]; then + cp -p "${MODULESDIR}/${x}" "${DESTDIR}${MODULESDIR}/${x}" + fi +done + +# MODULES=list case. Always honour. +for x in "${CONFDIR}/modules" /usr/share/initramfs-tools/modules.d/*; do + if [ -f "${x}" ]; then + add_modules_from_file "${x}" + fi +done + +# MODULES=most is default +case "${MODULES}" in +dep) + dep_add_modules + ;; +most) + auto_add_modules + ;; +netboot) + auto_add_modules base + auto_add_modules net + ;; +list) + # nothing to add + ;; +*) + echo "W: mkinitramfs: unsupported MODULES setting: ${MODULES}." >&2 + echo "W: mkinitramfs: Falling back to MODULES=most." >&2 + auto_add_modules + ;; +esac + +# Add firmware for built-in code +add_builtin_firmware + +# First file executed by linux +cp -p /usr/share/initramfs-tools/init "${DESTDIR}/init" + +# add existant boot scripts +for b in $(cd /usr/share/initramfs-tools/scripts/ && find . \ + -regextype posix-extended -regex '.*/[[:alnum:]\._-]+$' -type f); do + [ -d "${DESTDIR}/scripts/$(dirname "${b}")" ] \ + || mkdir -p "${DESTDIR}/scripts/$(dirname "${b}")" + cp -p "/usr/share/initramfs-tools/scripts/${b}" \ + "${DESTDIR}/scripts/$(dirname "${b}")/" +done +# Prune dot-files/directories and limit depth to exclude VCS files +for b in $(cd "${CONFDIR}/scripts" && find . -maxdepth 2 -name '.?*' -prune -o \ + -regextype posix-extended -regex '.*/[[:alnum:]\._-]+$' -type f -print); do + [ -d "${DESTDIR}/scripts/$(dirname "${b}")" ] \ + || mkdir -p "${DESTDIR}/scripts/$(dirname "${b}")" + cp -p "${CONFDIR}/scripts/${b}" "${DESTDIR}/scripts/$(dirname "${b}")/" +done + +echo "DPKG_ARCH=${DPKG_ARCH}" > "${DESTDIR}/conf/arch.conf" +cp -p "${CONFDIR}/initramfs.conf" "${DESTDIR}/conf" +for i in ${EXTRA_CONF}; do + copy_file config "${i}" /conf/conf.d +done + +# ROOT hardcoding +if [ -n "${ROOT:-}" ]; then + echo "ROOT=${ROOT}" > "${DESTDIR}/conf/conf.d/root" +fi + +if ! command -v ldd >/dev/null 2>&1 ; then + echo "E: no ldd around - install libc-bin" >&2 + exit 1 +fi + +# fstab and mtab +touch "${DESTDIR}/etc/fstab" +ln -s /proc/mounts "${DESTDIR}/etc/mtab" + +# module-init-tools +copy_exec /sbin/modprobe /sbin +copy_exec /sbin/rmmod /sbin +mkdir -p "${DESTDIR}/etc/modprobe.d" "${DESTDIR}/lib/modprobe.d" +for file in /etc/modprobe.d/*.conf /lib/modprobe.d/*.conf ; do + if test -e "$file" || test -L "$file" ; then + copy_file config "$file" + fi +done + +# Copy kernel modules here, because some hooks rely on them being copied +apply_add_modules +run_scripts /usr/share/initramfs-tools/hooks +run_scripts "${CONFDIR}"/hooks + +# cache boot run order +for b in $(cd "${DESTDIR}/scripts" && find . -mindepth 1 -type d); do + cache_run_scripts "${DESTDIR}" "/scripts/${b#./}" +done + +apply_add_modules +# Resolve hidden dependencies +hidden_dep_add_modules + +# decompress modules for boot speed, if possible +find "${DESTDIR}/${MODULESDIR}" -name '*.ko.*' | while read -r ko; do + case "$ko" in + *.xz) + if ! command -v xz >/dev/null 2>&1; then + break + fi + xz -d "${ko}" + ;; + *.zst) + if ! command -v zstd >/dev/null 2>&1; then + break + fi + zstd -q -d --rm "${ko}" + ;; + esac +done + +# generate module deps +depmod -a -b "${DESTDIR}" "${version}" +rm -f "${DESTDIR}/lib/modules/${version}"/modules.*map + +# make sure that library search path is up to date +cp -pPr /etc/ld.so.conf* "$DESTDIR"/etc/ +if ! ldconfig -r "$DESTDIR" ; then + [ "$(id -u)" != "0" ] \ + && echo "ldconfig might need uid=0 (root) for chroot()" >&2 +fi +# The auxiliary cache is not reproducible and is always invalid at boot +# (see #845034) +if [ -d "${DESTDIR}"/var/cache/ldconfig ]; then + rm -f "${DESTDIR}"/var/cache/ldconfig/aux-cache + rmdir --ignore-fail-on-non-empty "${DESTDIR}"/var/cache/ldconfig +fi + +# Apply DSDT to initramfs +if [ -e "${CONFDIR}/DSDT.aml" ]; then + copy_file DSDT "${CONFDIR}/DSDT.aml" +fi + +[ "${verbose}" = y ] && echo "Building cpio ${outfile} initramfs" + +# preserve permissions if root builds the image, see #633582 +[ "$(id -ru)" != 0 ] && cpio_owner_root="-R 0:0" + +# if SOURCE_DATE_EPOCH is set, try and create a reproducible image +if [ -n "${SOURCE_DATE_EPOCH}" ]; then + # ensure that no timestamps are newer than $SOURCE_DATE_EPOCH + find "${DESTDIR}" -newermt "@${SOURCE_DATE_EPOCH}" -print0 | \ + xargs -0r touch --no-dereference --date="@${SOURCE_DATE_EPOCH}" + + # --reproducible requires cpio >= 2.12 + cpio_reproducible="--reproducible" +fi + +# work around lack of "set -o pipefail" for pipes. +# Write exit code to FD 3 in case of a failure to pass it through the pipes. +{ + cd "${DESTDIR}" + { + find . || { echo "E: mkinitramfs failure find $?" >&2; echo 1 >&3; exit; } + } | { + LC_ALL=C sort || { echo "E: mkinitramfs failure sort $?" >&2; echo 1 >&3; exit; } + } | { + # shellcheck disable=SC2086 + cpio --quiet $cpio_owner_root $cpio_reproducible -o -H newc >"${__TMPMAINCPIO}" || + { echo "E: mkinitramfs failure cpio $?" >&2; echo 1 >&3; exit; } + } +} 3>&1 | { read -r exit_code; exit "${exit_code:-0}"; } || exit $? + +{ + if [ -s "${__TMPEARLYCPIO}" ]; then + cat "${__TMPEARLYCPIO}" || exit 1 + fi + + $compress -c "${__TMPMAINCPIO}" || + { echo "E: mkinitramfs failure $compress $?" >&2; exit 1; } + + if [ -s "${__TMPCPIOGZ}" ]; then + cat "${__TMPCPIOGZ}" || exit 1 + fi +} >"${outfile}" || exit 1 + +exit 0 diff --git a/mkinitramfs.8 b/mkinitramfs.8 new file mode 100644 index 0000000..9a3ddc1 --- /dev/null +++ b/mkinitramfs.8 @@ -0,0 +1,153 @@ +.TH MKINITRAMFS 8 "2018/07/18" "initramfs\-tools" "System Administration" + +.SH NAME +mkinitramfs \- low-level tool for generating an initramfs image + +.SH SYNOPSIS +.B mkinitramfs +.RI [ option ]... +.B \-o +.IR outfile +.RI [ version ] +.br +.BR mkinitramfs " " -h + +.SH DESCRIPTION +The +.B mkinitramfs +script generates an initramfs image. +The initramfs is a compressed cpio archive. The archive can be used on a +different box of the same arch with the corresponding Linux kernel. +.B mkinitramfs +is meant for advanced usage. On your local box +.B update-initramfs +calls +.B mkinitramfs +with the relevant parameters. +.B update-initramfs +keeps sha1sum of generated initramfs. It takes care to generate backups +and eventually runs the bootloader. + +At boot time, the kernel unpacks that archive into RAM disk, mounts and +uses it as initial root file system. All finding of the root device +happens in this early userspace. + +.SH OPTIONS +.TP +\fB\-c \fI compress +Override the +.B COMPRESS +setting in +.IR initramfs.conf . + +.TP +\fB\-d \fI confdir +Set an alternate configuration directory. + +.TP +\fB\-k +Keep the temporary directory used to make the image. + +.TP +\fB\-l \fI compresslevel +Override the +.B COMPRESSLEVEL +setting in +.IR initramfs.conf . + +.TP +\fB\-o \fI outfile +Write the image to +.IR outfile . + +.TP +\fB\-r \fI root +Override the +.B ROOT +setting in +.IR initramfs.conf . + +.TP +\fB\-v +Set the verbose mode output. + +.TP +\fIversion +Set the kernel version of the initramfs image +(defaults to the running kernel). + +.TP +\fB\-h\fR, \fB\-\-help\fR +Display usage information and exit. + +.SH ENVIRONMENT +.B mkinitramfs +honours the +.B TMPDIR +environment variable. If set, it uses subdirectories in the given +directory to create its temporary working directories. Else it uses +.I /var/tmp +as default value for that purpose. The given directory should be on a +filesystem which allows the execution of files stored there, i.e. +should not be mounted with the +.B noexec +mount option. + +If +.B SOURCE_DATE_EPOCH +is set, +.B mkinitramfs +attempts to generate a reproducible initramfs image. + +.SH FILES +.TP +.I /etc/initramfs-tools/initramfs.conf +The default configuration file for the script. See +.BR initramfs.conf (5) +for a description of the available configuration parameter. + +.TP +.I /etc/initramfs-tools/modules +Specified modules will be put in the generated image and loaded when the system boots. The format - one per line - is identical to that of +.I /etc/modules, +which is described in +.BR modules (5). + +.TP +.I /etc/initramfs-tools/conf.d +The conf.d directory allows one to hardcode bootargs at initramfs build time +via config snippets. This allows one to set ROOT or RESUME. +This is especially useful for bootloaders, which do not pass an root bootarg. + +.TP +.I /etc/initramfs-tools/DSDT.aml +If this file exists, it will be appended to the initramfs in a way that causes +it to be loaded by ACPI. + +.SH EXAMPLES + +Create an initramfs for current running kernel: + +.PP +.B mkinitramfs -o ~/tmp/initramfs-$(uname -r) + +Create an initramfs for specific kernel and keep builddirs: + +.PP +.B mkinitramfs -k -o ~/tmp/initramfs-2.6.21-686 2.6.21-686 + +Debug initramfs creation (check out written logfile) +.PP +.B sh -x mkinitramfs -o ~/tmp/initramfs-$(uname -r) 2> ~/tmp/log + +.SH AUTHOR +The initramfs-tools are written by Maximilian Attems <maks@debian.org>, +Jeff Bailey <jbailey@raspberryginger.com> and numerous others. + +.SH SEE ALSO +.BR +.IR initramfs.conf (5), +.IR initramfs-tools (7), +.IR update-initramfs (8), +.IR lsinitramfs (8), +.IR unmkinitramfs (8). |