I've rewritten the extract-ikconfig script to extract the kernel configuration from a kernel compiled with CONFIG_IKCONFIG. The main motivation for the rewrite was to remove the dependency on the external C program binoffset.c, which is compiled on the initial run. The binoffset executable is invoked with a relative path, which means that the old script can only be run from the top of the kernel tree, and only when you have write permission in the scripts directory. The new script uses tr/grep/tail/zcat only, and can be invoked from anywhere. The binoffset.c program has been removed. This script requires GNU grep 2.5 (released 2002-03-13) or higher, because the -o option was introduced in that version.
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| @@ -6,5 +6,4 @@ kallsyms · 5 unmodified lines | |||
| 6 | pnmtologo | 6 | pnmtologo |
| 7 | bin2c | 7 | bin2c |
| 8 | unifdef | 8 | unifdef |
| 9 | binoffset | ||
| 10 | ihex2fw | 9 | ihex2fw |
| @@ -1,163 +0,0 @@ | |||
| 1 | /*************************************************************************** | ||
| 2 | * binoffset.c | ||
| 3 | * (C) 2002 Randy Dunlap <rdunlap@xenotime.net> | ||
| 4 | |||
| 5 | # This program is free software; you can redistribute it and/or modify | ||
| 6 | # it under the terms of the GNU General Public License as published by | ||
| 7 | # the Free Software Foundation; either version 2 of the License, or | ||
| 8 | # (at your option) any later version. | ||
| 9 | # | ||
| 10 | # This program is distributed in the hope that it will be useful, | ||
| 11 | # but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
| 12 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
| 13 | # GNU General Public License for more details. | ||
| 14 | # | ||
| 15 | # You should have received a copy of the GNU General Public License | ||
| 16 | # along with this program; if not, write to the Free Software | ||
| 17 | # Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | ||
| 18 | |||
| 19 | # binoffset.c: | ||
| 20 | # - searches a (binary) file for a specified (binary) pattern | ||
| 21 | # - returns the offset of the located pattern or ~0 if not found | ||
| 22 | # - exits with exit status 0 normally or non-0 if pattern is not found | ||
| 23 | # or any other error occurs. | ||
| 24 | |||
| 25 | ****************************************************************/ | ||
| 26 | |||
| 27 | #include <stdio.h> | ||
| 28 | #include <stdlib.h> | ||
| 29 | #include <string.h> | ||
| 30 | #include <errno.h> | ||
| 31 | #include <unistd.h> | ||
| 32 | #include <fcntl.h> | ||
| 33 | #include <sys/types.h> | ||
| 34 | #include <sys/stat.h> | ||
| 35 | #include <sys/mman.h> | ||
| 36 | |||
| 37 | #define VERSION "0.1" | ||
| 38 | #define BUF_SIZE (16 * 1024) | ||
| 39 | #define PAT_SIZE 100 | ||
| 40 | |||
| 41 | char *progname; | ||
| 42 | char *inputname; | ||
| 43 | int inputfd; | ||
| 44 | unsigned int bix; /* buf index */ | ||
| 45 | unsigned char patterns [PAT_SIZE] = {0}; /* byte-sized pattern array */ | ||
| 46 | int pat_len; /* actual number of pattern bytes */ | ||
| 47 | unsigned char *madr; /* mmap address */ | ||
| 48 | size_t filesize; | ||
| 49 | int num_matches = 0; | ||
| 50 | off_t firstloc = 0; | ||
| 51 | |||
| 52 | void usage (void) | ||
| 53 | { | ||
| 54 | fprintf (stderr, "%s ver. %s\n", progname, VERSION); | ||
| 55 | fprintf (stderr, "usage: %s filename pattern_bytes\n", | ||
| 56 | progname); | ||
| 57 | fprintf (stderr, " [prints location of pattern_bytes in file]\n"); | ||
| 58 | exit (1); | ||
| 59 | } | ||
| 60 | |||
| 61 | void get_pattern (int pat_count, char *pats []) | ||
| 62 | { | ||
| 63 | int ix, err, tmp; | ||
| 64 | |||
| 65 | #ifdef DEBUG | ||
| 66 | fprintf (stderr,"get_pattern: count = %d\n", pat_count); | ||
| 67 | for (ix = 0; ix < pat_count; ix++) | ||
| 68 | fprintf (stderr, " pat # %d: [%s]\n", ix, pats[ix]); | ||
| 69 | #endif | ||
| 70 | |||
| 71 | for (ix = 0; ix < pat_count; ix++) { | ||
| 72 | tmp = 0; | ||
| 73 | err = sscanf (pats[ix], "%5i", &tmp); | ||
| 74 | if (err != 1 || tmp > 0xff) { | ||
| 75 | fprintf (stderr, "pattern or value error in pattern # %d [%s]\n", | ||
| 76 | ix, pats[ix]); | ||
| 77 | usage (); | ||
| 78 | } | ||
| 79 | patterns [ix] = tmp; | ||
| 80 | } | ||
| 81 | pat_len = pat_count; | ||
| 82 | } | ||
| 83 | |||
| 84 | void search_pattern (void) | ||
| 85 | { | ||
| 86 | for (bix = 0; bix < filesize; bix++) { | ||
| 87 | if (madr[bix] == patterns[0]) { | ||
| 88 | if (memcmp (&madr[bix], patterns, pat_len) == 0) { | ||
| 89 | if (num_matches == 0) | ||
| 90 | firstloc = bix; | ||
| 91 | num_matches++; | ||
| 92 | } | ||
| 93 | } | ||
| 94 | } | ||
| 95 | } | ||
| 96 | |||
| 97 | #ifdef NOTDEF | ||
| 98 | size_t get_filesize (int fd) | ||
| 99 | { | ||
| 100 | off_t end_off = lseek (fd, 0, SEEK_END); | ||
| 101 | lseek (fd, 0, SEEK_SET); | ||
| 102 | return (size_t) end_off; | ||
| 103 | } | ||
| 104 | #endif | ||
| 105 | |||
| 106 | size_t get_filesize (int fd) | ||
| 107 | { | ||
| 108 | int err; | ||
| 109 | struct stat stat; | ||
| 110 | |||
| 111 | err = fstat (fd, &stat); | ||
| 112 | fprintf (stderr, "filesize: %ld\n", err < 0 ? (long)err : stat.st_size); | ||
| 113 | if (err < 0) | ||
| 114 | return err; | ||
| 115 | return (size_t) stat.st_size; | ||
| 116 | } | ||
| 117 | |||
| 118 | int main (int argc, char *argv []) | ||
| 119 | { | ||
| 120 | progname = argv[0]; | ||
| 121 | |||
| 122 | if (argc < 3) | ||
| 123 | usage (); | ||
| 124 | |||
| 125 | get_pattern (argc - 2, argv + 2); | ||
| 126 | |||
| 127 | inputname = argv[1]; | ||
| 128 | |||
| 129 | inputfd = open (inputname, O_RDONLY); | ||
| 130 | if (inputfd == -1) { | ||
| 131 | fprintf (stderr, "%s: cannot open '%s'\n", | ||
| 132 | progname, inputname); | ||
| 133 | exit (3); | ||
| 134 | } | ||
| 135 | |||
| 136 | filesize = get_filesize (inputfd); | ||
| 137 | |||
| 138 | madr = mmap (0, filesize, PROT_READ, MAP_PRIVATE, inputfd, 0); | ||
| 139 | if (madr == MAP_FAILED) { | ||
| 140 | fprintf (stderr, "mmap error = %d\n", errno); | ||
| 141 | close (inputfd); | ||
| 142 | exit (4); | ||
| 143 | } | ||
| 144 | |||
| 145 | search_pattern (); | ||
| 146 | |||
| 147 | if (munmap (madr, filesize)) | ||
| 148 | fprintf (stderr, "munmap error = %d\n", errno); | ||
| 149 | |||
| 150 | if (close (inputfd)) | ||
| 151 | fprintf (stderr, "%s: error %d closing '%s'\n", | ||
| 152 | progname, errno, inputname); | ||
| 153 | |||
| 154 | fprintf (stderr, "number of pattern matches = %d\n", num_matches); | ||
| 155 | if (num_matches == 0) | ||
| 156 | firstloc = ~0; | ||
| 157 | printf ("%ld\n", firstloc); | ||
| 158 | fprintf (stderr, "%ld\n", firstloc); | ||
| 159 | |||
| 160 | exit (num_matches ? 0 : 2); | ||
| 161 | } | ||
| 162 | |||
| 163 | /* end binoffset.c */ | ||
| @@ -1,92 +1,53 @@ | |||
| 1 | #!/bin/sh | 1 | #!/bin/sh |
| 2 | # extracts .config info from a [b]zImage file | 2 | # ---------------------------------------------------------------------- |
| 3 | # uses: binoffset (new), dd, zcat, strings, grep | 3 | # extract-ikconfig - Extract the .config file from a kernel image |
| 4 | # $arg1 is [b]zImage filename | 4 | # |
| 5 | 5 | # This will only work when the kernel was compiled with CONFIG_IKCONFIG. | |
| 6 | binoffset="./scripts/binoffset" | 6 | # |
| 7 | test -e $binoffset || cc -o $binoffset ./scripts/binoffset.c || exit 1 | 7 | # The obscure use of the "tr" filter is to work around older versions of |
| 8 | 8 | # "grep" that report the byte offset of the line instead of the pattern. | |
| 9 | IKCFG_ST="0x49 0x4b 0x43 0x46 0x47 0x5f 0x53 0x54" | 9 | # |
| 10 | IKCFG_ED="0x49 0x4b 0x43 0x46 0x47 0x5f 0x45 0x44" | 10 | # (c) 2009, Dick Streefland <dick@streefland.net> |
| 11 | dump_config() { | 11 | # Licensed under the terms of the GNU General Public License. |
| 12 | file="$1" | 12 | # ---------------------------------------------------------------------- |
| 13 | 13 | ||
| 14 | start=`$binoffset $file $IKCFG_ST 2>/dev/null` | 14 | gz1='\037\213\010' |
| 15 | [ "$?" != "0" ] && start="-1" | 15 | gz2='01' |
| 16 | if [ "$start" -eq "-1" ]; then | 16 | cf1='IKCFG_ST\037\213\010' |
| 17 | return | 17 | cf2='0123456789' |
| 18 | fi | 18 | |
| 19 | end=`$binoffset $file $IKCFG_ED 2>/dev/null` | 19 | dump_config() |
| 20 | [ "$?" != "0" ] && end="-1" | ||
| 21 | if [ "$end" -eq "-1" ]; then | ||
| 22 | return | ||
| 23 | fi | ||
| 24 | |||
| 25 | start=`expr $start + 8` | ||
| 26 | size=`expr $end - $start` | ||
| 27 | |||
| 28 | dd if="$file" ibs=1 skip="$start" count="$size" 2>/dev/null | zcat | ||
| 29 | |||
| 30 | clean_up | ||
| 31 | exit 0 | ||
| 32 | } | ||
| 33 | |||
| 34 | |||
| 35 | usage() | ||
| 36 | { | ||
| 37 | echo " usage: extract-ikconfig [b]zImage_filename" | ||
| 38 | } | ||
| 39 | |||
| 40 | clean_up() | ||
| 41 | { | 20 | { |
| 42 | if [ "$TMPFILE" != "" ]; then | 21 | if pos=`tr "$cf1\n$cf2" "\n$cf2=" < "$1" | grep -abo "^$cf2"` |
| 43 | rm -f $TMPFILE | 22 | then |
| 23 | pos=${pos%%:*} | ||
| 24 | tail -c+$(($pos+8)) "$1" | zcat -q | ||
| 25 | exit 0 | ||
| 44 | fi | 26 | fi |
| 45 | } | 27 | } |
| 46 | 28 | ||
| 47 | if [ $# -lt 1 ] | 29 | # Check invocation: |
| 30 | me=${0##*/} | ||
| 31 | img=$1 | ||
| 32 | if [ $# -ne 1 -o ! -s "$img" ] | ||
| 48 | then | 33 | then |
| 49 | usage | 34 | echo "Usage: $me <kernel-image>" >&2 |
| 50 | exit 1 | 35 | exit 2 |
| 51 | fi | 36 | fi |
| 52 | 37 | ||
| 53 | TMPFILE=`mktemp -t ikconfig-XXXXXX` || exit 1 | 38 | # Initial attempt for uncompressed images or objects: |
| 54 | image="$1" | 39 | dump_config "$img" |
| 55 | 40 | ||
| 56 | # vmlinux: Attempt to dump the configuration from the file directly | 41 | # That didn't work, so decompress and try again: |
| 57 | dump_config "$image" | 42 | tmp=/tmp/ikconfig$$ |
| 58 | 43 | trap "rm -f $tmp" 0 | |
| 59 | GZHDR1="0x1f 0x8b 0x08 0x00" | 44 | for pos in `tr "$gz1\n$gz2" "\n$gz2=" < "$img" | grep -abo "^$gz2"` |
| 60 | GZHDR2="0x1f 0x8b 0x08 0x08" | 45 | do |
| 61 | 46 | pos=${pos%%:*} | |
| 62 | ELFHDR="0x7f 0x45 0x4c 0x46" | 47 | tail -c+$pos "$img" | zcat 2> /dev/null > $tmp |
| 63 | 48 | dump_config $tmp | |
| 64 | # vmlinux.gz: Check for a compressed images | 49 | done |
| 65 | off=`$binoffset "$image" $GZHDR1 2>/dev/null` | 50 | |
| 66 | [ "$?" != "0" ] && off="-1" | 51 | # Bail out: |
| 67 | if [ "$off" -eq "-1" ]; then | 52 | echo "$me: Cannot find kernel config." >&2 |
| 68 | off=`$binoffset "$image" $GZHDR2 2>/dev/null` | ||
| 69 | [ "$?" != "0" ] && off="-1" | ||
| 70 | fi | ||
| 71 | if [ "$off" -eq "0" ]; then | ||
| 72 | zcat <"$image" >"$TMPFILE" | ||
| 73 | dump_config "$TMPFILE" | ||
| 74 | elif [ "$off" -ne "-1" ]; then | ||
| 75 | (dd ibs="$off" skip=1 count=0 && dd bs=512k) <"$image" 2>/dev/null | \ | ||
| 76 | zcat >"$TMPFILE" | ||
| 77 | dump_config "$TMPFILE" | ||
| 78 | |||
| 79 | # check if this is simply an ELF file | ||
| 80 | else | ||
| 81 | off=`$binoffset "$image" $ELFHDR 2>/dev/null` | ||
| 82 | [ "$?" != "0" ] && off="-1" | ||
| 83 | if [ "$off" -eq "0" ]; then | ||
| 84 | dump_config "$image" | ||
| 85 | fi | ||
| 86 | fi | ||
| 87 | |||
| 88 | echo "ERROR: Unable to extract kernel configuration information." | ||
| 89 | echo " This kernel image may not have the config info." | ||
| 90 | |||
| 91 | clean_up | ||
| 92 | exit 1 | 53 | exit 1 |