FilesExpand file tree

 master

/

extract-ikconfig

Copy path

Blame

More file actions

Blame

More file actions

Latest commit

 

History

History

History

executable file

·

67 lines (59 loc) · 1.64 KB

 master

/

extract-ikconfig

Copy path

Top

File metadata and controls

• Code
• Blame

executable file

·

67 lines (59 loc) · 1.64 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

67

#!/bin/sh

# ----------------------------------------------------------------------

# 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()

{

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

}

try_decompress()

{

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

}

# Check invocation:

me=${0##*/}

img=$1

if [ $# -ne 1 -o ! -s "$img" ]

then

echo "Usage: $me <kernel-image>" >&2

exit 2

fi

# Prepare temp files:

tmp1=/tmp/ikconfig$$.1

tmp2=/tmp/ikconfig$$.2

trap "rm -f $tmp1 $tmp2" 0

# Initial attempt for uncompressed images or objects:

dump_config "$img"

# That didn't work, so retry after decompression.

try_decompress '\037\213\010' xy gunzip

try_decompress '\3757zXZ\000' abcde unxz

try_decompress 'BZh' xy bunzip2

try_decompress '\135\0\0\0' xxx unlzma

try_decompress '\211\114\132' xy 'lzop -d'

# Bail out:

echo "$me: Cannot find kernel config." >&2

exit 1