#!/bin/bash
#
# Nagios plugin to check clamav daemon status
# 
# Author : Benjamin Renard <brenard@easter-eggs.com>
# Date : Wed, 12 Jun 2019 13:15:33 +0200
# Source : http://gogs.zionetrix.net/check_clamd
#

CLAMDSCAN=clamdscan
FILE_TO_CHECK="/etc/mtab"
DEBUG=0

function debug() {
	if [ $DEBUG -eq 1 ]
	then
		>&2 echo -e "[DEBUG] $1"
	fi
}

function usage() {
	cat << EOF
Usage : $0 [-d] [-h] [options]
	-c			Path to clamdscan (Default : auto-detected)
	-f			Path of the file to check with clamdscan (Default : $FILE_TO_CHECK)
	-d			Debug mode
	-h 			Show this message
EOF
}

while getopts "hf:c:n:d" OPTION
do
	case $OPTION in
		f)
			FILE_TO_CHECK=$OPTARG
		;;
		c)
			CLAMDSCAN=$OPTARG
		;;
		d)
			DEBUG=1
		;;
		h)
			usage
			exit 0
		;;
		*)
			echo "Unkown option '$OPTION'"
			usage
			exit 1
	esac
done

CMD="$CLAMDSCAN --stream --stdout --infected --no-summary $FILE_TO_CHECK"
debug "clamdscan command = '$CMD'"

ERRORS=$( $CMD 2>&1 )
EXITCODE=$?

debug "clamdscan exit code = $EXITCODE"
debug "clamdscan output =\n$ERRORS"

if [ $EXITCODE -ne 0 ]
then
	echo "CRITICAL - clamdscan exit with $EXITCODE"
	[ -n "$ERRORS" ] && echo -e "clamdscan return:\n$ERRORS"
	exit 2
elif [ -z "$ERRORS" ]
then
	echo "OK - Clamav daemon is running and answer to scan request"
	exit 0
else
	echo "WARNING - clamdscan return some errors checking $FILE_TO_CHECK file"
	echo -e "$ERRORS"
	exit 1
fi