#!/bin/bash
#
# rtpengine		Startup script for NGCP rtpengine
#
# chkconfig: 345 84 16
# description: NGCP rtpengine
#
# processname: rtpengine
# config: /etc/sysconfig/rtpengine
# pidfile: /run/rtpengine.pid
#
### BEGIN INIT INFO
# Provides: rtpengine
# Required-Start: $local_fs $network
# Short-Description: NGCP rtpengine
# Description: NGCP rtpengine 
### END INIT INFO

# Source function library.
. /etc/rc.d/init.d/functions

# defaults

if [ -f /etc/sysconfig/rtpengine ]
then
        . /etc/sysconfig/rtpengine
else
	echo "Error: /etc/sysconfig/rtpengine not present" >&2
	exit 6
fi

rtpengine=/usr/bin/rtpengine
prog=rtpengine
pidfile=${PIDFILE-/run/rtpengine.pid}
lockfile=${LOCKFILE-/var/lock/subsys/rtpengine}
cachefile=/var/lib/ngcp-rtpengine/rtpengine.cfg
TABLE=$(/usr/sbin/rtpengine-get-table --config-file="${CONFIG_FILE-/etc/rtpengine/rtpengine.conf}")
PIDFILE=${pidfile}
RETVAL=0
OPTS=""

build_opts() {
        # kernel table
	MODULE=0
	# the variable from the config is the source of truth
	if [[ -n "$TABLE" ]];then
		if [[ $TABLE -ge 0 ]];then
			MODULE=1
		fi
	fi

	# options
	[[ "$FORK" == "no" ]] && OPTS+=" --foreground"
	[ -z "$CONFIG_FILE" ] || OPTS+=" --config-file=$CONFIG_FILE"
	[ -z "$CONFIG_SECTION" ] || OPTS+=" --config-section=$CONFIG_SECTION"
	[ -z "$PIDFILE" ] || OPTS+=" --pidfile=$PIDFILE"
}

start() {
	build_opts
	if [[ $MODULE == 1 ]];then
		echo "Loading module for in-kernel packet forwarding"
		rmmod xt_RTPENGINE 2> /dev/null
		if [[ -n "$SET_USER" ]];then
			if [[ -n "$SET_GROUP" ]];then
				proc_gid="$(grep "^$SET_GROUP:" /etc/group | cut -f3 -d:)"
			else
				proc_gid="$(id "$SET_USER" -g)"
			fi
			modprobe xt_RTPENGINE proc_uid="$(id "$SET_USER" -u)" proc_gid="$proc_gid"
		else
			modprobe xt_RTPENGINE
		fi
		if firewall-cmd --state 2>/dev/null ; then
			# Using firewalld
			# Need to check if the INPUT_prefilter chain is present (permanently)
			if ! firewall-cmd --permanent --direct --query-chain ipv4 filter INPUT_prefilter > /dev/null; then
				firewall-cmd --permanent --direct --add-chain ipv4 filter INPUT_prefilter
				firewall-cmd --permanent --direct --passthrough ipv4 -t filter -I INPUT -j INPUT_prefilter
				firewall-cmd --reload
			fi
				
			firewall-cmd --direct --add-chain ipv4 filter rtpengine
			firewall-cmd --direct --add-rule ipv4 filter INPUT_prefilter 0 -j rtpengine
			firewall-cmd --direct --add-rule ipv4 filter rtpengine 0 -p udp -j RTPENGINE --id "$TABLE"
			firewall-cmd --direct --add-rule ipv6 filter rtpengine 0 -p udp -j RTPENGINE --id "$TABLE"
  			firewall-cmd --reload
		else
			for fw in iptables ip6tables;do
				# We insert the rtpengine rule at the top of the input chain
				if ! $fw -t filter -C INPUT -j rtpengine 2> /dev/null; then
					$fw -N rtpengine
					$fw -t filter -I INPUT -j rtpengine
				fi
				if ! $fw -I rtpengine -p udp -j RTPENGINE --id "$TABLE" 2> /dev/null; then
					$fw -I rtpengine -p udp -j RTPENGINE --id "$TABLE"
				fi
			done
		fi

		cat <<EOF > "$cachefile"
CUR_TABLE=$TABLE
EOF
	fi
        echo -n $"Starting $prog: "
	if [[ -n "$SET_USER" ]];then
		# shellcheck disable=SC2086
		daemon --user "$SET_USER" --pidfile="${pidfile}" "$rtpengine" $OPTS
	else
		# shellcheck disable=SC2086
		daemon --pidfile="${pidfile}" "$rtpengine" $OPTS
	fi
        RETVAL=$?
        echo
        [ $RETVAL = 0 ] && touch "${lockfile}"
        return $RETVAL
}

stop() {
	echo -n $"Stopping $prog: "
	killproc -p "${pidfile}" "$rtpengine"
	RETVAL=$?
	echo
	if [ -f "$cachefile" ];then
		. "$cachefile"
		echo "Unloading module for in-kernel packet forwarding"
		echo "del $TABLE" > /proc/rtpengine/control
		if firewall-cmd --state 2>/dev/null; then
			firewall-cmd --direct --remove-rules ipv4 filter rtpengine
			firewall-cmd --direct --remove-rules ipv6 filter rtpengine
			firewall-cmd --direct --remove-rule ipv4 filter INPUT_prefilter 0 -j rtpengine
			firewall-cmd --direct --remove-chain ipv4 filter rtpengine
			firewall-cmd --reload
		else
			for fw in iptables ip6tables;do
				$fw -D rtpengine -p udp -j RTPENGINE --id "$CUR_TABLE"
				$fw -t filter -D INPUT -j rtpengine
				$fw -X rtpengine
			done
		fi
		rmmod xt_RTPENGINE
		rm -f "$cachefile"
	fi
 
	[ $RETVAL = 0 ] && rm -f "${lockfile}" "${pidfile}"
}

# See how we were called.
case "$1" in
  start)
	start
	;;
  stop)
	stop
	;;
  status)
        status -p "${pidfile}" "$rtpengine"
	RETVAL=$?
	;;
  restart)
	stop
	start
	;;
  condrestart|try-restart)
	if status -p "${pidfile}" "$rtpengine" >&/dev/null; then
		stop
		start
	fi
	;;
  *)
	echo $"Usage: $prog {start|stop|restart|condrestart|try-restart|status}"
	RETVAL=2
esac

exit $RETVAL