diff options
Diffstat (limited to 'scripts/extract-ikconfig')
-rwxr-xr-x | scripts/extract-ikconfig | 130 |
1 files changed, 52 insertions, 78 deletions
diff --git a/scripts/extract-ikconfig b/scripts/extract-ikconfig index de233ff..1512c0a 100755 --- a/scripts/extract-ikconfig +++ b/scripts/extract-ikconfig @@ -1,92 +1,66 @@ #!/bin/sh -# extracts .config info from a [b]zImage file -# uses: binoffset (new), dd, zcat, strings, grep -# $arg1 is [b]zImage filename - -binoffset="./scripts/binoffset" -test -e $binoffset || cc -o $binoffset ./scripts/binoffset.c || exit 1 - -IKCFG_ST="0x49 0x4b 0x43 0x46 0x47 0x5f 0x53 0x54" -IKCFG_ED="0x49 0x4b 0x43 0x46 0x47 0x5f 0x45 0x44" -dump_config() { - file="$1" - - start=`$binoffset $file $IKCFG_ST 2>/dev/null` - [ "$?" != "0" ] && start="-1" - if [ "$start" -eq "-1" ]; then - return - fi - end=`$binoffset $file $IKCFG_ED 2>/dev/null` - [ "$?" != "0" ] && end="-1" - if [ "$end" -eq "-1" ]; then - return - fi - - start=`expr $start + 8` - size=`expr $end - $start` - - dd if="$file" ibs=1 skip="$start" count="$size" 2>/dev/null | zcat - - clean_up - exit 0 -} - - -usage() +# ---------------------------------------------------------------------- +# extract-ikconfig - Extract the .config file from a kernel image +# +# This will only work when the kernel was compiled with CONFIG_IKCONFIG. +# +# The obscure use of the "tr" filter is to work around older versions of +# "grep" that report the byte offset of the line instead of the pattern. +# +# (c) 2009,2010 Dick Streefland <dick@streefland.net> +# Licensed under the terms of the GNU General Public License. +# ---------------------------------------------------------------------- + +cf1='IKCFG_ST\037\213\010' +cf2='0123456789' + +dump_config() { - echo " usage: extract-ikconfig [b]zImage_filename" + if pos=`tr "$cf1\n$cf2" "\n$cf2=" < "$1" | grep -abo "^$cf2"` + then + pos=${pos%%:*} + tail -c+$(($pos+8)) "$1" | zcat > $tmp1 2> /dev/null + if [ $? != 1 ] + then # exit status must be 0 or 2 (trailing garbage warning) + cat $tmp1 + exit 0 + fi + fi } -clean_up() +try_decompress() { - if [ "$TMPFILE" != "" ]; then - rm -f $TMPFILE - fi + for pos in `tr "$1\n$2" "\n$2=" < "$img" | grep -abo "^$2"` + do + pos=${pos%%:*} + tail -c+$pos "$img" | $3 > $tmp2 2> /dev/null + dump_config $tmp2 + done } -if [ $# -lt 1 ] +# Check invocation: +me=${0##*/} +img=$1 +if [ $# -ne 1 -o ! -s "$img" ] then - usage - exit 1 + echo "Usage: $me <kernel-image>" >&2 + exit 2 fi -TMPFILE=`mktemp -t ikconfig-XXXXXX` || exit 1 -image="$1" - -# vmlinux: Attempt to dump the configuration from the file directly -dump_config "$image" - -GZHDR1="0x1f 0x8b 0x08 0x00" -GZHDR2="0x1f 0x8b 0x08 0x08" - -ELFHDR="0x7f 0x45 0x4c 0x46" +# Prepare temp files: +tmp1=/tmp/ikconfig$$.1 +tmp2=/tmp/ikconfig$$.2 +trap "rm -f $tmp1 $tmp2" 0 -# vmlinux.gz: Check for a compressed images -off=`$binoffset "$image" $GZHDR1 2>/dev/null` -[ "$?" != "0" ] && off="-1" -if [ "$off" -eq "-1" ]; then - off=`$binoffset "$image" $GZHDR2 2>/dev/null` - [ "$?" != "0" ] && off="-1" -fi -if [ "$off" -eq "0" ]; then - zcat <"$image" >"$TMPFILE" - dump_config "$TMPFILE" -elif [ "$off" -ne "-1" ]; then - (dd ibs="$off" skip=1 count=0 && dd bs=512k) <"$image" 2>/dev/null | \ - zcat >"$TMPFILE" - dump_config "$TMPFILE" - -# check if this is simply an ELF file -else - off=`$binoffset "$image" $ELFHDR 2>/dev/null` - [ "$?" != "0" ] && off="-1" - if [ "$off" -eq "0" ]; then - dump_config "$image" - fi -fi +# Initial attempt for uncompressed images or objects: +dump_config "$img" -echo "ERROR: Unable to extract kernel configuration information." -echo " This kernel image may not have the config info." +# That didn't work, so retry after decompression. +try_decompress '\037\213\010' xy gunzip +try_decompress 'BZh' xy bunzip2 +try_decompress '\135\0\0\0' xxx unlzma +try_decompress '\211\114\132' xy 'lzop -d' -clean_up +# Bail out: +echo "$me: Cannot find kernel config." >&2 exit 1 |