#!/bin/sh

# Script writen by Daniel Jakots for BGP, adapted by Jeremy Dubois for OSPF

# First we go through the list of neighbor and we write all the peer and
# their status in "${_TMPDIR}"/ospf6-status.

# Then we monitor if this file has changed between now and the previous run.

# If it did, we send a mail with the states of the different sessions.

set -u

PATH=$HOME/bin:/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin:.

_MAILTO="{{ ospf_mailto }}"
_TMPDIR=/tmp/check-ospf6
_PIDFILE="${_TMPDIR}"/ospf6d-check-peers.pid


if [ -e /etc/realname ]; then
    _REALNAME=$(cat /etc/realname)
    _HOSTNAME=$(hostname -s)
else
    _HOSTNAME=$(hostname)
fi

mkdir -p "${_TMPDIR}"

# Don't try to run if it's already running
if [ -e "${_PIDFILE}" ]; then
    echo "$(date)" >> "${_TMPDIR}"/log
    exit 1
else
    echo $$ >> "${_PIDFILE}"
fi

# Create an history
if [[ -f "${_TMPDIR}"/ospf6-status ]] ; then
    mv "${_TMPDIR}"/ospf6-status "${_TMPDIR}"/ospf6-status.old
else
    touch "${_TMPDIR}"/ospf6-status
    touch "${_TMPDIR}"/ospf6-status.old
fi

# List peers and loops on them to list them and their OSPF6 state
ospf6ctl show neighbor | grep -v "^$" | grep -v "Uptime" | awk {'print $1'} > "${_TMPDIR}"/peers-list

while read -r _PEER
do
    _STATUS=$(/usr/sbin/ospf6ctl show neighbor | grep "${_PEER} " | awk {'print $3'})
    echo -n "${_PEER}" >> "${_TMPDIR}"/ospf6-status
    echo -n " " >> "${_TMPDIR}"/ospf6-status
    if ([[ "${_STATUS}" = "FULL/BCKUP" ]] || [[ "${_STATUS}" = "FULL/DR" ]] || [[ "${_STATUS}" = "2-WAY/OTHER" ]] || [[ "${_STATUS}" = "FULL/OTHER" ]]) ; then
       _STATUS="UP"
    else
       _STATUS="DOWN"
    fi
    echo "${_STATUS}" >> "${_TMPDIR}"/ospf6-status

done <"${_TMPDIR}"/peers-list

# Check for difference with previous run
different=$(diff -q "${_TMPDIR}"/ospf6-status.old "${_TMPDIR}"/ospf6-status)

if ! [[ -n "${different}" ]] ; then
    rm -f "${_PIDFILE}"
    exit 0
fi

# It changed so we're going to send a mail

_TMPMAILDIR="${_TMPDIR}"/mail
mkdir -p "${_TMPMAILDIR}"

# go through sessions and list them depending on their OSPF6 state
echo "*** Session(s) OK ***\n" >> "${_TMPMAILDIR}"/bodyok
while read -r _LINE
do
    # _LINE is session + status
    _STATUS=$(echo "${_LINE}" | awk {'print $2'})
    _SESSION=$(echo "${_LINE}" | awk {'print $1'})
    if [[ "${_STATUS}" = "UP" ]] ; then
        ospf6ctl show neighbor | grep "${_SESSION} " {{ ospf_sed_command }} >> "${_TMPMAILDIR}"/bodyok
    else
        ospf6ctl show neighbor | grep "${_SESSION} " {{ ospf_sed_command }} >> "${_TMPMAILDIR}"/bodynok
    fi
done <"${_TMPDIR}"/ospf6-status

# create the mail body

echo "Dear NOC,\n\nThe state of one or more OSPF6 session(s) has changed:\n" > "${_TMPMAILDIR}"/header
cat "${_TMPMAILDIR}"/header "${_TMPMAILDIR}"/bodyok > "${_TMPMAILDIR}"/body

_STATE="OK"
if [[ -f "${_TMPMAILDIR}"/bodynok ]] ; then
    _STATE="NOT OK"
    echo "\n*** Session(s) on error ***\n" >> "${_TMPMAILDIR}"/body
    cat "${_TMPMAILDIR}"/bodynok >> "${_TMPMAILDIR}"/body
fi

# Add some infos
echo "\n\n*** Known OSPF routes ***\n" >>  "${_TMPMAILDIR}"/body
ospf6ctl show fib ospf >>  "${_TMPMAILDIR}"/body

echo "\n\n*** OSPF interfaces state ***\n" >>  "${_TMPMAILDIR}"/body
ospf6ctl show interfaces >>  "${_TMPMAILDIR}"/body

echo "\n\n*** Network used memory ***\n" >>  "${_TMPMAILDIR}"/body
netstat -m >>  "${_TMPMAILDIR}"/body

echo "\n\n*** Server load ***\n" >>  "${_TMPMAILDIR}"/body
w >>  "${_TMPMAILDIR}"/body

echo "\n\n*** Processes ***\n" >>  "${_TMPMAILDIR}"/body
top >>  "${_TMPMAILDIR}"/body

# Send the mail whether we have a realname or not
if [ -n "${_REALNAME}" ]; then
    cat "${_TMPMAILDIR}"/body | mail -s "[OSPF6] ${_REALNAME} (${_HOSTNAME}) - State change - ${_STATE}" "${_MAILTO}"
else
    cat "${_TMPMAILDIR}"/body | mail -s "[OSPF6] ${_HOSTNAME} - State change - ${_STATE}" "${_MAILTO}"
fi

# cleaning
if [[ -d  "${_TMPMAILDIR}" ]] ; then
    rm -rf  "${_TMPMAILDIR}"
fi
rm -f "${_PIDFILE}"