Mkinitramfs script file analysis, location/usr/sbin/mkinitramfs, mkinitramfssbin
Mkinitramfs-o/boot/initrd. img-version
The following is a script file:
#! /Bin/sh
Umask 0022
Export PATH = '/usr/bin:/sbin:/bin'
# Defaults
Keep = "n"
CONFDIR = "/etc/initramfs-tools"
Verbose = "n"
Test-e/bin/busybox & BUSYBOXDIR =/bin
Test-e/usr/lib/initramfs-tools/bin/busybox & BUSYBOXDIR =/usr/lib/initramfs-tools/bin
Export BUSYBOXDIR
OPTIONS = 'getopt-o c: d: ko: r: v-n "$0" -- "$ @"'
# Check for non-GNU getopt
If [$? ! = 0]; then echo "W: non-GNU getopt"> & 2; exit 1; fi
Eval set -- "$ 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
;;
-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 =''
For I in/usr/share/initramfs-tools/conf. d/* $ {CONFDIR}/conf. d/*; do
[-E $ I] & EXTRA_CONF = "$ {EXTRA_CONF} $ (basename $ I \
| Grep '^ [[: alnum:] [[: alnum:] \. _-] * $ '| grep-v '\. dpkg -. * $ ')";
Done
# FIXME: deprecated those settings on mkinitramfs run
# These conf dirs are for boot scripts and land on initramfs
For I in $ {EXTRA_CONF}; do
If [-e $ {CONFDIR}/conf. d/$ {I}]; then
. $ {CONFDIR}/conf. d/$ {I}
Elif [-e/usr/share/initramfs-tools/conf. d/$ {I}]; then
./Usr/share/initramfs-tools/conf. d/$ {I}
Fi
Done
# Source package confs
For I in/usr/share/initramfs-tools/conf-hooks.d/*; do
If [-e "$ {I}"]; then
. "$ {I }"
Fi
Done
If [-n "$ {UMASK:-}"]; then
Umask "$ {UMASK }"
Fi
If [-z "$ {outfile}"]; then
Usage
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
# Check that we're using a new enough kernel version, first for ourselves,
# Then for each of the hooks, which can have a MINKVER variable defined
Check_minkver $ {version}
Check_minkver $ {version}/usr/share/initramfs-tools/hooks
Check_minkver $ {version }$ {CONFDIR}/hooks
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 1
;;
Esac
# Check userspace and kernel support for compressed initramfs images
If [-z "$ {compress:-}"]; then
Compress =$ {COMPRESS}
Else
COMPRESS =$ {compress}
Fi
If! Command-v "$ {compress}">/dev/null 2> & 1; then
Compress = gzip
["$ {Verbose}" = y] & \
Echo "No $ {COMPRESS} in $ {PATH}, using gzip"
COMPRESS = gzip
Fi
If! 'Grep-q-I ^ config_rd _ $ {COMPRESS % p}/boot/config-$ {version} '; then
Compress = gzip
["$ {Verbose}" = y] & \
Echo "linux-2.6 misses $ {COMPRESS} support, using gzip"
Fi
["$ {Compress}" = lzop] & compress = "lzop-9"
["$ {Compress}" = xz] & compress = "xz-8 -- check = crc32"
If [-d "$ {outfile}"]; then
Echo "$ {outfile} is a directory"> & 2
Exit 1
Fi
MODULESDIR = "/lib/modules/$ {version }"
If [! -E "$ {MODULESDIR}"]; then
Echo "WARNING: missing $ {MODULESDIR }"
Echo "Device driver support needs thus be built-in linux image! "
Fi
If [! -E "$ {MODULESDIR}/modules. dep"]; then
Depmod $ {version}
Fi
DESTDIR = "$ (mktemp-d $ {TMPDIR:-/tmp}/mkinitramfs_XXXXXX)" | exit 1
Chmod 755 "$ {DESTDIR }"
# Do not execute cache_run_scripts () if mounted with noexec
NOEXEC = ""
Fs = $ (df-P $ DESTDIR | tail-1 | awk '{print $6 }')
If [-n "$ fs"] & mount | grep-q "on $ fs. * noexec"; then
NOEXEC = 1
Fi
_ TMPCPIOGZ = "$ (mktemp $ {TMPDIR:-/tmp}/mkinitramfs-OL_XXXXXX)" | exit 1
_ TMPEARLYCPIO = "$ (mktemp $ {TMPDIR:-/var/tmp}/mkinitramfs-FW_XXXXXX)" | exit 1
DPKG_ARCH = 'dpkg -- print-System'
# Export environment for hook scripts.
#
Export MODULESDIR
Export version
Export CONFDIR
Export DESTDIR
Export DPKG_ARCH
Export verbose
Export MODULES
Export BUSYBOX
Export COMPCACHE_SIZE
# Private, used by 'catenate _ cpiogz '.
Export _ TMPCPIOGZ
# Private, used by 'prepend _ earlyinitramfs '.
Export _ TMPEARLYCPIO
For d in bin conf/conf. d etc lib/modules run sbin scripts $ {MODULESDIR}; do
Mkdir-p "$ {DESTDIR}/$ {d }"
Done
# Copy in modules. builtin and modules. order (not generated by depmod)
For x in modules. builtin modules. order; do
If [-f "$ {MODULESDIR}/$ {x}"]; then
Cp-p "$ {MODULESDIR}/$ {x}" "$ {DESTDIR }$ {MODULESDIR}/$ {x }"
Fi
Done
# MODULES = list case. Always honor.
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 }."
Echo "W: mkinitramfs: Falling back to MODULES = most ."
Auto_add_modules
;;
Esac
# Resolve hidden dependencies
Hidden_dep_add_modules
# First file executed by linux-2.6
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
Option = $ (sed '/^ OPTION = /! D; $ d; s/^ OPTION = //; s/[[: space:] * $ // '"/usr/share/initramfs-tools/scripts/$ {B }")
[-Z "$ {option}"] | eval test-n \ "\$ {$ option} \"-a \ "\$ {$ option }\"! = \ "N \" | continue
[-D "$ {DESTDIR}/scripts/$ (dirname" $ {B} ")"] \
| Mkdir-p "$ {DESTDIR}/scripts/$ (dirname" $ {B }")"
Cp-p "/usr/share/initramfs-tools/scripts/$ {B }"\
"$ {DESTDIR}/scripts/$ (dirname" $ {B }")/"
Done
For B in $ (cd "$ {CONFDIR}/scripts" & find .\
-Regextype posix-extended-regex '. */[[: alnum:] \. _-] + $'-type f); do
Option = $ (sed '/^ OPTION = /! D; $ d; s/^ OPTION = //; s/[[: space:] * $ // '"$ {CONFDIR}/scripts/$ {B }")
[-Z "$ {option}"] | eval test-n \ "\$ {$ option} \"-a \ "\$ {$ option }\"! = \ "N \" | continue
[-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
If [-e "$ {CONFDIR}/conf. d/$ {I}"]; then
Copy_exec "$ {CONFDIR}/conf. d/$ {I}"/conf. d
Elif [-e "/usr/share/initramfs-tools/conf. d/$ {I}"]; then
Copy_exec "/usr/share/initramfs-tools/conf. d/$ {I}"/conf. d
Fi
Done
# ROOT hardcoding
If [-n "$ {ROOT:-}"]; then
Echo "ROOT =$ {ROOT}" >$ {DESTDIR}/conf. d/root
Fi
If! Command-v ldd>/dev/null 2> & 1; then
Echo "WARNING: no ldd around-install libc-bin"> & 2
Exit 1
Fi
Copy_exec/usr/lib/initramfs-tools/bin/wait-for-root/sbin
# Module-init-tools
Copy_exec/sbin/modprobe/sbin
Copy_exec/sbin/rmmod/sbin
Mkdir-p "$ {DESTDIR}/etc/modprobe. d"
Cp-a/etc/modprobe. d/* "$ {DESTDIR}/etc/modprobe. d /"
# Util-linux
Copy_exec/sbin/blkid/sbin
# Workaround: libgcc always needed on old-abi arm
If ["$ DPKG_ARCH" = arm] | ["$ DPKG_ARCH" = armeb]; then
Cp-a/lib/libgcc_s.so.1 "$ {DESTDIR}/lib /"
Fi
Run_scripts/usr/share/initramfs-tools/hooks optional
Run_scripts "$ {CONFDIR}"/hooks optional
# Cache boot run order
If [-n "$ NOEXEC"]; then
Echo "W: TMPDIR is mounted noexec, will not cache run scripts ."
Else
For B in $ (cd "$ {DESTDIR}/scripts" & find.-mindepth 1-type d); do
Cache_run_scripts "$ {DESTDIR}" "/scripts/$ {B #./}"
Done
Fi
# 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-ar/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
# Apply DSDT to initramfs
If [-e "$ {CONFDIR}/DSDT. aml"]; then
Copy_exec "$ {CONFDIR}/DSDT. aml "/
Fi
# Remove any looping or broken symbolic links, since they break cpio.
["$ {Verbose}" = y] & xargs_verbose = "-t"
(Cd "$ {DESTDIR}" & find. -type l-printf' % p % Y \ n' | sed-n's/[LN] $ // P '\
| Xargs ${xargs_verbose:-}-rL1 rm-f)
# Dirty hack for armhf's double-linker situation; if we have one
# The two known eglibc linkers, nuke both and re-create sanity
If ["$ DPKG_ARCH" = armhf]; then
If [-e "$ {DESTDIR}/lib/arm-linux-gnueabihf/ld-linux.so.3"] | \
[-E "$ {DESTDIR}/lib/ld-linux-armhf.so.3"]; then
Rm-f "$ {DESTDIR}/lib/arm-linux-gnueabihf/ld-linux.so.3"
Rm-f "$ {DESTDIR}/lib/ld-linux-armhf.so.3"
Cp-aL/lib/ld-linux-armhf.so.3 "$ {DESTDIR}/lib /"
Ln-sf/lib/ld-linux-armhf.so.3 "$ {DESTDIR}/lib/arm-linux-gnueabihf/ld-linux.so.3"
Fi
Fi
["$ {Verbose}" = y] & echo "Building cpio $ {outfile} initramfs"
If [-s "$ {__ TMPEARLYCPIO}"]; then
Cat "$ {__ TMPEARLYCPIO}"> "$ {outfile}" | exit 1
Else
# Truncate
> "$ {Outfile }"
Fi
(
# Work around lack of "set-o pipefail" for the following pipe:
# Cd "$ {DESTDIR}" & find. | cpio -- quiet-R 0: 0-o-H newc | gzip> "$ {outfile}" | exit 1
Exec 3> & 1
Eval'
# Http://cfaj.freeshell.org/shell/cus-faq-2.html
Exec 4> & 1> & 3 3> &-
Cd "$ {DESTDIR }"
{
Find. 4> &-; echo "ec1 =$ ?; "> & 4
} | {
Cpio -- quiet-R 0: 0-o-H newc 4> &-; echo "ec2 =$ ?; "> & 4
} | $ {Compress }>> "$ {outfile }"
Echo "ec3 = $ ?; "> & 4
`
If ["$ ec1"-ne 0]; then
Echo "E: mkinitramfs failure find $ ec1 cpio $ ec2 $ compress $ ec3"
Exit "$ ec1"
Fi
If ["$ ec2"-ne 0]; then
Echo "E: mkinitramfs failure cpio $ ec2 $ compress $ ec3"
Exit "$ ec2"
Fi
If ["$ ec3"-ne 0]; then
Echo "E: mkinitramfs failure $ compress $ ec3"
Exit "$ ec3"
Fi
) | Exit 1
If [-s "$ {__ TMPCPIOGZ}"]; then
Cat "$ {__ TMPCPIOGZ}" >>" $ {outfile} "| exit 1
Fi
If ["$ {keep}" = "y"]; then
Echo "Working files in $ {DESTDIR}, early initramfs in $ {__ TMPEARLYCPIO} and overlay in $ {__ TMPCPIOGZ }"
Else
Rm-rf "$ {DESTDIR }"
Rm-rf "$ {__ TMPCPIOGZ }"
Rm-rf "$ {__ TMPEARLYCPIO }"
Fi
Exit 0
