dsa-nagios-checks/checks/dsa-check-running-kernel

   1 #!/bin/bash
   2
   3 # Check if the running kernel has the same version string as the on-disk
   4 # kernel image.
   5
   6 # Copyright 2008,2009,2011 Peter Palfrader
   7 # Copyright 2009 Stephen Gran
   8 # Copyright 2010 Uli Martens
   9 # Copyright 2011 Alexander Reichle-Schmehl
  10 #
  11 # Permission is hereby granted, free of charge, to any person obtaining
  12 # a copy of this software and associated documentation files (the
  13 # "Software"), to deal in the Software without restriction, including
  14 # without limitation the rights to use, copy, modify, merge, publish,
  15 # distribute, sublicense, and/or sell copies of the Software, and to
  16 # permit persons to whom the Software is furnished to do so, subject to
  17 # the following conditions:
  18 #
  19 # The above copyright notice and this permission notice shall be
  20 # included in all copies or substantial portions of the Software.
  21 #
  22 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 # EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 # MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29
  30 OK=0;
  31 WARNING=1;
  32 CRITICAL=2;
  33 UNKNOWN=3;
  34
  35 get_offset() {
  36         local file needle
  37
  38         file="$1"
  39         needle="$2"
  40         perl -e '
  41                 undef $/;
  42                 $i = index(<>, "'"$needle"'");
  43                 if ($i < 0) {
  44                         exit 1;
  45                 };
  46                 print $i,"\n"' < "$file"
  47 }
  48
  49 get_avail() {
  50         # This is wrong, but leaves room for when we have to care for machines running
  51         # myfirstunix-image-0.1-dsa-arm
  52         local prefix="$1"; shift
  53
  54         local kervers=$(uname -r)
  55
  56         local metavers=''
  57
  58         # DSA uses kernel versions of the form 2.6.29.3-dsa-dl380-oldxeon, where
  59         # Debian uses versions of the form 2.6.29-2-amd64
  60         if [ "${kervers#3}" != "$kervers" ]; then
  61                 metavers=$(echo $kervers | sed -r -e 's/^3\.[0-9].[0-9]+-[A-Za-z0-9\.]+-(.*)/\1/')
  62         elif [ "${kervers//dsa}" != "$kervers" ]; then
  63                 metavers=$(echo $kervers | sed -r -e 's/^2\.(4|6)\.[0-9]+([\.0-9]+?)-(.*)/2.\1-\3/')
  64         else
  65                 metavers=$(echo $kervers | sed -r -e 's/^2\.(4|6)\.[0-9]+-[A-Za-z0-9\.]+-(.*)/2.\1-\2/')
  66         fi
  67
  68         # Attempt to track back to a metapackage failed.  bail
  69         if [ "$metavers" = "$kervers" ]; then
  70                 return 2
  71         fi
  72
  73         # We're just going to give up if we can't find a matching metapackage
  74         # I tried being strict once, and it just caused a lot of headaches.  We'll see how
  75         # being lax does for us
  76
  77         local output=$(apt-cache policy ${prefix}-image-${metavers} 2>/dev/null)
  78         local metaavailvers=$(echo "$output" | grep '^  Candidate:' | awk '{print $2}')
  79         local metainstavers=$(echo "$output" | grep '^  Installed:' | awk '{print $2}')
  80
  81         if [ -z "$metaavailvers" ] || [ "$metaavailvers" = '(none)' ]; then
  82                 return 2
  83         fi
  84         if [ -z "$metainstavers" ] || [ "$metainstavers" = '(none)' ]; then
  85                 return 2
  86         fi
  87
  88         if [ "$metaavailvers" != "$metainstavers" ] ; then
  89                 echo "${prefix}-image-${metavers} $metaavailvers available but $metainstavers installed"
  90                 return 1
  91         fi
  92
  93         local imagename=0
  94         # --no-all-versions show shows only the candidate
  95         for vers in $(apt-cache --no-all-versions show ${prefix}-image-${metavers} | sed -n 's/^Depends: //p' | tr ',' '\n' | tr -d ' ' | grep ${prefix}-image | awk '{print $1}' | sort -u); do
  96                 if dpkg --compare-versions "1.$vers" gt "1.$imagename"; then
  97                         imagename=$vers
  98                 fi
  99         done
 100
 101         if [ -z "$imagename" ] || [ "$imagename" = 0 ]; then
 102                 return 2
 103         fi
 104
 105         if [ "$imagename" != "${prefix}-image-${kervers}" ]; then
 106                 if dpkg --compare-versions 1."$imagename" lt 1."${prefix}-image-${kervers}"; then
 107                         return 2
 108                 fi
 109                 echo "$imagename" != "${prefix}-image-${kervers}"
 110                 return 1
 111         fi
 112
 113         local availvrs=$(apt-cache policy ${imagename} 2>/dev/null | grep '^  Candidate' | awk '{print $2}')
 114         local kernelversion=$(apt-cache policy ${prefix}-image-${kervers} 2>/dev/null | grep '^  Installed:' | awk '{print $2}')
 115
 116         if [ "$availvrs" = "$kernelversion" ]; then
 117                 return 0
 118         fi
 119
 120         echo "$kernelversion != $availvrs"
 121         return 1
 122 }
 123
 124 get_image_linux() {
 125         local image GZHDR1 GZHDR2 LZHDR off
 126
 127         image="$1"
 128
 129         GZHDR1="\x1f\x8b\x08\x00"
 130         GZHDR2="\x1f\x8b\x08\x08"
 131         LZHDR1="\x00\x00\x00\x02\xff"
 132         LZHDR2="\x00\x00\x00\x04\xff"
 133
 134         off=`get_offset "$image" $GZHDR1`
 135         [ "$?" != "0" ] && off="-1"
 136         if [ "$off" -eq "-1" ]; then
 137                 off=`get_offset "$image" $GZHDR2`
 138                 [ "$?" != "0" ] && off="-1"
 139         fi
 140         if [ "$off" -eq "0" ]; then
 141                 zcat < "$image"
 142                 return
 143         elif [ "$off" -ne "-1" ]; then
 144                 (dd ibs="$off" skip=1 count=0 && dd bs=512k) < "$image"  2>/dev/null | zcat 2>/dev/null
 145                 return
 146         fi
 147
 148         off=`get_offset "$image" $LZHDR1`
 149         [ "$?" != "0" ] && off="-1"
 150         if [ "$off" -eq "-1" ]; then
 151                 off=`get_offset "$image" $LZHDR2`
 152                 [ "$?" != "0" ] && off="-1"
 153         fi
 154         if [ "$off" -ne "-1" ]; then
 155                 (dd ibs="$[off-1]" skip=1 count=0 && dd bs=512k) < "$image" 2>/dev/null | xzcat 2>/dev/null
 156                 return
 157         fi
 158
 159         echo "ERROR: Unable to extract kernel image." 2>&1
 160         exit 1
 161 }
 162
 163
 164 freebsd_check_running_version() {
 165         local imagefile="$1"; shift
 166
 167         local r="$(uname -r)"
 168         local v="$(uname -v| sed -e 's/^#[0-9]*/&:/')"
 169
 170         local q='@\(#\)FreeBSD '"$r $v"
 171
 172         if zcat "$imagefile" | $STRINGS | egrep -q "$q"; then
 173                 echo "OK"
 174         else
 175                 echo "not OK"
 176         fi
 177 }
 178
 179 STRINGS="";
 180 if [ -x "$(which strings)" ]; then
 181         STRINGS="$(which strings)"
 182 elif [ -x "$(which busybox)" -a "$( echo foobar | $(which busybox) strings 2>/dev/null)" = "foobar" ]; then
 183         STRINGS="$(which busybox) strings"
 184 fi
 185
 186 searched=""
 187 for on_disk in \
 188         "/boot/vmlinuz-`uname -r`"\
 189         "/boot/vmlinux-`uname -r`"\
 190         "/boot/kfreebsd-`uname -r`.gz"; do
 191
 192         if [ -e "$on_disk" ]; then
 193                 if [ -z "$STRINGS" ]; then
 194                         echo "UNKNOWN: 'strings' command missing, perhaps install binutils or busybox?"
 195                         exit $UNKNOWN
 196                 fi
 197                 if [ "${on_disk/vmlinu}" != "$on_disk" ]; then
 198                         on_disk_version="`get_image_linux "$on_disk" | $STRINGS | grep 'Linux version' | head -n1`"
 199                         if [ -x /usr/bin/lsb_release ] ; then
 200                                 vendor=$(lsb_release -i -s)
 201                                 if [ -n "$vendor" ] && [ "xDebian" != "x$vendor" ] ; then
 202                                         on_disk_version=$( echo $on_disk_version|sed -e "s/ ($vendor [[:alnum:]\.-]\+ [[:alnum:]\.]\+)//")
 203                                 fi
 204                         fi
 205                         [ -z "$on_disk_version" ] || break
 206                         on_disk_version="`cat "$on_disk" | $STRINGS | grep 'Linux version' | head -n1`"
 207                         [ -z "$on_disk_version" ] || break
 208
 209                         echo "UNKNOWN: Failed to get a version string from image $on_disk"
 210                         exit $UNKNOWN
 211                 else
 212                         on_disk_version="$(zcat $on_disk | $STRINGS | grep Debian | head -n 1 | sed -e 's/Debian [[:alnum:]]\+ (\(.*\))/\1/')"
 213                 fi
 214         fi
 215         searched="$searched $on_disk"
 216 done
 217
 218 if ! [ -e "$on_disk" ]; then
 219         echo "WARNING: Did not find a kernel image (checked$searched) - I have no idea which kernel I am running"
 220         exit $WARNING
 221 fi
 222
 223 if [ "$(uname -s)" = "Linux" ]; then
 224         running_version="`cat /proc/version`"
 225         if [ -z "$running_version" ] ; then
 226                 echo "UNKNOWN: Failed to get a version string from running system"
 227                 exit $UNKNOWN
 228         fi
 229
 230         if [ "$running_version" != "$on_disk_version" ]; then
 231                 echo "WARNING: Running kernel does not match on-disk kernel image: [$running_version != $on_disk_version]"
 232                 exit $WARNING
 233         fi
 234
 235         ret="$(get_avail linux)"
 236         if [ $? = 1 ]; then
 237                 echo "WARNING: Kernel needs upgrade [$ret]"
 238                 exit $WARNING
 239         fi
 240 else
 241         image_current=$(freebsd_check_running_version $on_disk)
 242         running_version="`uname -s` `uname -r` `uname -v`"
 243         if [ "$image_current" != "OK" ]; then
 244                 approx_time="$(date -d "@`stat -c '%Y' "$on_disk"`" +"%Y-%m-%d %H:%M:%S")"
 245                 echo "WARNING: Currently running kernel ($running_version) does not match on disk image (~ $approx_time)"
 246                 exit $WARNING;
 247         fi
 248
 249         ret="$(get_avail linux)"
 250         if [ $? = 1 ]; then
 251                 echo "WARNING: Kernel needs upgrade [$ret]"
 252                 exit $WARNING
 253         fi
 254 fi
 255
 256 echo "OK: Running kernel matches on disk image: [$running_version]"
 257 exit $OK