check_os_release

#!/bin/bash

# check_os_release
# https://github.com/hobbyquaker/check_os_release
#
# Simple Nagios/Icinga check for support end of Linux distributions.
#
# Currently only Debian, Raspbian and Ubuntu are supported, Pull Requests welcome!
# MIT Licensed, Copyright 2018, 2019 https://github.com/hobbyquaker

VERSION="2.0.7"

RELEASE_FILE="/etc/os-release"
DEBIAN_URL="https://debian.pages.debian.net/distro-info-data/debian.csv"
UBUNTU_URL="https://debian.pages.debian.net/distro-info-data/ubuntu.csv"
SCHEDULE_FILE="/tmp/os_release_schedule.csv"
SCHEDULE_FILE_MAXAGE=30

WARN_MONTHS=3
CRIT_MONTHS=1
DEB_LTS=0


while getopts 'w:c:lhv' OPT; do
  case $OPT in
    w)  WARN_MONTHS=$OPTARG;;
    c)  CRIT_MONTHS=$OPTARG;;
    h)
        echo "usage: $0 [ -w value ] [ -c value ] [ -l ]
    -w Warn if supports ends in less then given months      [default: 3]
    -c Critical if supports ends in less then given months  [default: 1]
    -l Use Debian LTS                                       [default: false]
    -h print this help screen
    -v show version
"
        exit 0
        ;;
    l)  DEB_LTS=1;;
    v)
        echo "$0 $VERSION"
        exit 0
        ;;
  esac
done


WARNING=$(date --date="+$WARN_MONTHS month" +"%Y-%m-%d")
CRITICAL=$(date --date="+$CRIT_MONTHS month" +"%Y-%m-%d")
TODAY=$(date +"%Y-%m-%d")


if [ ! -f $RELEASE_FILE ]; then
    echo "UNKNOWN: $RELEASE_FILE missing"
    exit 3
fi

source $RELEASE_FILE

case "$ID" in
    "ubuntu")
        REGEX="^$(echo $VERSION_ID | sed 's/\./\\./g')\s*\(LTS\)\?,"
        URL=$UBUNTU_URL
        ;;
    "debian") ;&
    "raspbian")
        REGEX="^$(echo $VERSION_ID | sed 's/\./\\./g'),"
        URL=$DEBIAN_URL
        ;;
    *)
        # TODO other Distributions...
        echo "UNKNOWN: unknown distribution ID=$ID (ID_LIKE=$ID_LIKE)"
        exit 3
        ;;
esac

if [ ! -s $SCHEDULE_FILE ] ; then
    rm -f $SCHEDULE_FILE
fi

if [ ! -f $SCHEDULE_FILE ]; then
    wget -q $URL -O $SCHEDULE_FILE.tmp
    if [ $? -ne 0 ]; then
        echo "UNKNOWN: failed to download release schedule from $URL"
        exit 3
    else
        mv $SCHEDULE_FILE.tmp $SCHEDULE_FILE
        touch $SCHEDULE_FILE
    fi
elif [[ $(find "$SCHEDULE_FILE" -mtime +$SCHEDULE_FILE_MAXAGE -print) ]]; then
    wget -q $URL -O $SCHEDULE_FILE.tmp && mv $SCHEDULE_FILE.tmp $SCHEDULE_FILE && touch $SCHEDULE_FILE
fi


LINE=$(cat $SCHEDULE_FILE | grep $REGEX)

if [ -z "$LINE" ]; then
    echo "UNKNOWN: $ID $VERSION_ID not found in release schedule"
    exit 3
fi


VERSION=$(echo $LINE | cut -d ',' -f1)
CODENAME=$(echo $LINE | cut -d ',' -f2)
RELEASE=$(echo $LINE | cut -d ',' -f5)


if [ $DEB_LTS -ne 0 ] && [ "$ID" = "debian" ]; then
    EOL=$(date --date="$RELEASE+5 years" +"%Y-%m-%d")
    ESTIMATE=" (estimated)"
    SUPPORT="LTS"
else
    EOL=$(echo $LINE | cut -d ',' -f6)
    SUPPORT="Support"
fi


if [ -z "$EOL" ] && [ "$ID" = "debian" ]; then
    EOL=$(date --date="$RELEASE+3 years" +"%Y-%m-%d")
    ESTIMATE=" (estimated)"
elif [ -z "$EOL" ] && [ "$ID_LIKE" = "debian" ]; then
    EOL=$(date --date="$RELEASE+3 years" +"%Y-%m-%d")
    ESTIMATE=" (estimated)"
elif [ -z "$EOL" ]; then
    echo "UNKNOWN: EOL Date for $ID $VERSION_ID not found in release schedule"
    exit 3
fi


if [ $EOL \< $TODAY ]; then
    echo "CRITICAL: ${SUPPORT} for $NAME $VERSION ($CODENAME) ended $EOL$ESTIMATE"
    exit 2
elif [ $EOL \< $CRITICAL ]; then
    echo "CRITICAL: ${SUPPORT} for $NAME $VERSION ($CODENAME) ends $EOL$ESTIMATE"
    exit 2
elif [ $EOL \< $WARNING ]; then
    echo "WARNING: ${SUPPORT} for $NAME $VERSION ($CODENAME) ends $EOL$ESTIMATE"
    exit 1
else
    echo "OK: ${SUPPORT} for $NAME $VERSION ($CODENAME) ends $EOL$ESTIMATE"
    exit 0
fi