1 files changed, 92 insertions, 0 deletions
diff --git a/scripts/extract-ikconfig b/scripts/extract-ikconfig
new file mode 100755
index 00000000000..de233ff43c1
--- /dev/null
+++ b/scripts/extract-ikconfig
@@ -0,0 +1,92 @@
+#!/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()
+{
+	echo "  usage: extract-ikconfig [b]zImage_filename"
+}
+
+clean_up()
+{
+	if [ "$TMPFILE" != "" ]; then
+		rm -f $TMPFILE
+	fi
+}
+
+if [ $# -lt 1 ]
+then
+	usage
+	exit 1
+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"
+
+# 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
+
+echo "ERROR: Unable to extract kernel configuration information."
+echo "       This kernel image may not have the config info."
+
+clean_up
+exit 1