dsa-check-running-kernel: Check from all compression tokens

[mirror/dsa-nagios.git] / dsa-nagios-checks / checks / dsa-check-running-kernel

diff --git a/dsa-nagios-checks/checks/dsa-check-running-kernel b/dsa-nagios-checks/checks/dsa-check-running-kernel
index a5874dc..ca4170e 100755 (executable)
--- a/dsa-nagios-checks/checks/dsa-check-running-kernel
+++ b/dsa-nagios-checks/checks/dsa-check-running-kernel
@@ -3,9 +3,9 @@
 # Check if the running kernel has the same version string as the on-disk
 # kernel image.
 
-# Copyright 2008,2009,2011 Peter Palfrader
+# Copyright 2008,2009,2011,2012,2013,2014 Peter Palfrader
 # Copyright 2009 Stephen Gran
-# Copyright 2010 Uli Martens
+# Copyright 2010,2012,2013 Uli Martens
 # Copyright 2011 Alexander Reichle-Schmehl
 #
 # Permission is hereby granted, free of charge, to any person obtaining
@@ -37,9 +37,11 @@ get_offset() {
 
        file="$1"
        needle="$2"
+       pos="$3"
+
        perl -e '
                undef $/;
-               $i = index(<>, "'"$needle"'");
+               $i = index(<>, "'"$needle"'", '"$pos"');
                if ($i < 0) {
                        exit 1;
                };
@@ -121,35 +123,45 @@ get_avail() {
        return 1
 }
 
-get_image_linux() {
-       local image GZHDR1 GZHDR2 LZHDR off
+cat_vmlinux() {
+       local image header filter hdroff
 
        image="$1"
+       header="$2"
+       filter="$3"
+       hdroff="$4"
+       nextoff=0
+
+       while : ; do
+               off=`get_offset "$image" $header $nextoff`
+               local ret="$?"
+               if [ "$ret" != 0 ]; then
+                       # not found, exit
+                       return 1
+               fi
 
-       GZHDR1="\x1f\x8b\x08\x00"
-       GZHDR2="\x1f\x8b\x08\x08"
-       LZHDR="\x00\x00\x00\x02\xff"
+               (if [ "$off" != 0 ]; then
+                  dd ibs="$((off+hdroff))" skip=1 count=0
+                fi &&
+                dd bs=512k) < "$image"  2>/dev/null | $filter 2>/dev/null
+               nextoff=$((off + 1))
+       done
+       return 0
+}
 
-       off=`get_offset "$image" $GZHDR1`
-       [ "$?" != "0" ] && off="-1"
-       if [ "$off" -eq "-1" ]; then
-               off=`get_offset "$image" $GZHDR2`
-               [ "$?" != "0" ] && off="-1"
-       fi
-       if [ "$off" -eq "0" ]; then
-               zcat < "$image"
-               return
-       elif [ "$off" -ne "-1" ]; then
-               (dd ibs="$off" skip=1 count=0 && dd bs=512k) < "$image"  2>/dev/null | zcat 2>/dev/null
-               return
-       fi
+get_image_linux() {
+       local image
 
-       off=`get_offset "$image" $LZHDR`
-       [ "$?" != "0" ] && off="-1"
-       if [ "$off" -ne "-1" ]; then
-               (dd ibs="$[off-1]" skip=1 count=0 && dd bs=512k) < "$image" 2>/dev/null | xzcat 2>/dev/null
-               return
-       fi
+       image="$1"
+
+       # gzip compressed image
+       cat_vmlinux "$image" "\x1f\x8b\x08\x00"      "zcat"   0
+       cat_vmlinux "$image" "\x1f\x8b\x08\x08"      "zcat"   0
+       # lzma compressed image
+       cat_vmlinux "$image" "\x00\x00\x00\x02\xff"  "xzcat" -1
+       cat_vmlinux "$image" "\x00\x00\x00\x04\xff"  "xzcat" -1
+       # xz compressed image
+       cat_vmlinux "$image" "\xfd\x37\x7a\x58\x5a " "xzcat"  0
 
        echo "ERROR: Unable to extract kernel image." 2>&1
        exit 1
@@ -164,13 +176,20 @@ freebsd_check_running_version() {
 
        local q='@\(#\)FreeBSD '"$r $v"
 
-       if zcat "$imagefile" | strings | egrep -q "$q"; then
+       if zcat "$imagefile" | $STRINGS | egrep -q "$q"; then
                echo "OK"
        else
                echo "not OK"
        fi
 }
 
+STRINGS="";
+if [ -x "$(which strings)" ]; then
+       STRINGS="$(which strings)"
+elif [ -x "$(which busybox)" -a "$( echo foobar | $(which busybox) strings 2>/dev/null)" = "foobar" ]; then
+       STRINGS="$(which busybox) strings"
+fi
+
 searched=""
 for on_disk in \
        "/boot/vmlinuz-`uname -r`"\
@@ -178,12 +197,12 @@ for on_disk in \
        "/boot/kfreebsd-`uname -r`.gz"; do
 
        if [ -e "$on_disk" ]; then
-               if [ ! -x "$(which strings)" ]; then
-                       echo "UNKNOWN: 'strings' command missing, perhaps install binutils?"
+               if [ -z "$STRINGS" ]; then
+                       echo "UNKNOWN: 'strings' command missing, perhaps install binutils or busybox?"
                        exit $UNKNOWN
                fi
                if [ "${on_disk/vmlinu}" != "$on_disk" ]; then
-                       on_disk_version="`get_image_linux "$on_disk" | strings | grep 'Linux version' | head -n1`"
+                       on_disk_version="`get_image_linux "$on_disk" | $STRINGS | grep 'Linux version' | head -n1`"
                        if [ -x /usr/bin/lsb_release ] ; then
                                vendor=$(lsb_release -i -s)
                                if [ -n "$vendor" ] && [ "xDebian" != "x$vendor" ] ; then
@@ -191,13 +210,13 @@ for on_disk in \
                                fi
                        fi
                        [ -z "$on_disk_version" ] || break
-                       on_disk_version="`cat "$on_disk" | strings | grep 'Linux version' | head -n1`"
+                       on_disk_version="`cat "$on_disk" | $STRINGS | grep 'Linux version' | head -n1`"
                        [ -z "$on_disk_version" ] || break
 
                        echo "UNKNOWN: Failed to get a version string from image $on_disk"
                        exit $UNKNOWN
                else
-                       on_disk_version="$(zcat $on_disk | strings | grep Debian | head -n 1 | sed -e 's/Debian [[:alnum:]]\+ (\(.*\))/\1/')"
+                       on_disk_version="$(zcat $on_disk | $STRINGS | grep Debian | head -n 1 | sed -e 's/Debian [[:alnum:]]\+ (\(.*\))/\1/')"
                fi
        fi
        searched="$searched $on_disk"