#!/bin/bash
#daemon_monitor - look at all processes with a PPID of 1 and make sure
#                 that everything that should be running is, and that
#                 no other daemons are running on your system
# Copyright Brian Brazil <bbrazil@netsoc.tcd.ie> 2005
# http://www.netsoc.tcd.ie/~bbrazil/code/brmon
# $Id: daemon_monitor,v 1.1 2005/12/26 17:17:27 bbrazil Exp $
#
#    This program is free software; you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation; version 2 of the License.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program; if not, write to the Free Software
#    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA


#These should be sorted files with 'username args' e.g.
#mailman /usr/local/bin/python /usr/local/mailman/bin/mailmanctl -s -q start
#This *is* case sensitive - its also the output format.
SYSTEM_DAEMONS=~/sys_daemons		#Things that should always be running
KNOWN_DAEMONS=~/known_daemons		#Things that might be running

#Filter to pass unknown daemons through - set to 'cat' if you don't want to filter
#Default:
filter(){ cat; }
#Ignore screen
#filter(){ egrep -vi '^[^ ]+ +screen(| .*)$'; }


#These seem to work on Solaris and GNU/Linux
PS=/bin/ps
SED=/bin/sed
SORT=/usr/bin/sort
COMM=/usr/bin/comm

DAEMONS=$($PS -e -o 'ppid user args' | $SED -n 's/^ *1  *\(.*\)$/\1/p' | $SORT)

MISSING=$(cat << EOF |
$DAEMONS
EOF
comm -13 - $SYSTEM_DAEMONS )

UNKNOWN=$(cat << EOF |
$DAEMONS
EOF
comm -23 - $SYSTEM_DAEMONS | filter | comm -23 - $KNOWN_DAEMONS )

SUBJECT=
MESSAGE=

if [ x != "x$MISSING" ]; then
	SUBJECT="$HOSTNAME: Some daemons not running"
	MESSAGE=$(
	cat << EOF
The following daemons are not running:
$MISSING

EOF
)
fi

if [ x != "x$UNKNOWN" ]; then
	SUBJECT="$HOSTNAME: Warning - unknown daemons"
	MESSAGE=$(
	cat << EOF
$MESSAGE

The following unknown daemons are running:
$UNKNOWN

EOF
)
fi

[ x == "x$SUBJECT" ] && exit 0

mail -s "$SUBJECT" root << EOF
$MESSAGE
EOF