#!/bin/bash
#
#  Check saved file md5sum's against current md5sum's to
#  monitor for changes in file content.
#  Assumes that the /etc/nagios/md5s file has already been
#  generated on the client for use with "md5sum -c FILE"
#
#  To use add a new NRPE service that executes check_file_md5s
#  and define the command in nrpe.cfg on the client
#
#  Author:  Stephen Berg, Jacobs Contractor, Naval Research Lab
#           Stennis Space Center, MS
current_md5s=`mktemp`
saved_md5s=/etc/nagios/md5s

STATE_OK=0
STATE_WARNING=1
STATE_CRITICAL=2
STATE_UNKNOWN=3
STATE_DEPENDENT=4

/usr/bin/md5sum -c $saved_md5s > $current_md5s 2>&1

file_count=`wc -l $saved_md5s | awk '{ print $1 }'`
ok_count=`/bin/grep -c OK $current_md5s`
failed_count=`/bin/grep -c FAILED $current_md5s`

if [ $ok_count -eq $file_count ]
then
    echo "All monitored files (${ok_count}/${file_count}) are OK."
    cat ${current_md5s}
    /bin/rm ${current_md5s}
    exit $STATE_OK
else
    grep WARNING $current_md5s
    grep FAILED $current_md5s
    cat ${current_md5s} | grep OK
    /bin/rm ${current_md5s}
    exit $STATE_WARNING
fi