#!/bin/sh
### BEGIN INIT INFO
# Provides:       dnsmasq
# Required-Start: $network $remote_fs $syslog
# Required-Stop:  $network $remote_fs $syslog
# Default-Start:  2 3 4 5
# Default-Stop:   0 1 6
# Description:    DHCP and DNS server
### END INIT INFO

# Don't exit on error status
set +e

PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
DAEMON=/usr/sbin/dnsmasq
NAME=dnsmasq
DESC="DNS forwarder and DHCP server"

# Most configuration options in /etc/default/dnsmasq are deprecated
# but still honoured.
ENABLED=1
if [ -r /etc/default/$NAME ]; then
	. /etc/default/$NAME
fi

# Get the system locale, so that messages are in the correct language, and the 
# charset for IDN is correct
if [ -r /etc/default/locale ]; then
        . /etc/default/locale
        export LANG
fi

# The following test ensures the dnsmasq service is not started, when the
# package 'dnsmasq' is removed but not purged, even if the dnsmasq-base 
# package is still in place.
test -e /usr/share/dnsmasq/installed-marker || exit 0
 
test -x $DAEMON || exit 0

# Provide skeleton LSB log functions for backports which don't have LSB functions.
if [ -f /lib/lsb/init-functions ]; then
         . /lib/lsb/init-functions
else
         log_warning_msg () {
            echo "${@}."
         }

         log_success_msg () {
            echo "${@}."
         }

         log_daemon_msg () {
            echo -n "${1}: $2"
         }

	 log_end_msg () {
            if [ $1 -eq 0 ]; then
              echo "."
            elif [ $1 -eq 255 ]; then
              /bin/echo -e " (warning)."
            else
              /bin/echo -e " failed!"
            fi
         }
fi

# RESOLV_CONF:
# If the resolvconf package is installed then use the resolv conf file
# that it provides as the default.  Otherwise use /etc/resolv.conf as
# the default.
#
# If IGNORE_RESOLVCONF is set in /etc/default/dnsmasq or an explicit
# filename is set there then this inhibits the use of the resolvconf-provided
# information.
#
# Note that if the resolvconf package is installed it is not possible to 
# override it just by configuration in /etc/dnsmasq.conf, it is necessary
# to set IGNORE_RESOLVCONF=yes in /etc/default/dnsmasq.

if [ ! "$RESOLV_CONF" ] &&
   [ "$IGNORE_RESOLVCONF" != "yes" ] &&
   [ -x /sbin/resolvconf ]
then
	RESOLV_CONF=/run/dnsmasq/resolv.conf
fi

for INTERFACE in $DNSMASQ_INTERFACE; do
	DNSMASQ_INTERFACES="$DNSMASQ_INTERFACES -i $INTERFACE"
done

for INTERFACE in $DNSMASQ_EXCEPT; do
	DNSMASQ_INTERFACES="$DNSMASQ_INTERFACES -I $INTERFACE"
done

if [ ! "$DNSMASQ_USER" ]; then
   DNSMASQ_USER="dnsmasq"
fi

# This tells dnsmasq to ignore DNS requests that don't come from a local network.
# It's automatically ignored if  --interface --except-interface, --listen-address 
# or --auth-server exist in the configuration, so for most installations, it will
# have no effect, but for otherwise-unconfigured installations, it stops dnsmasq
# from being vulnerable to DNS-reflection attacks.

DNSMASQ_OPTS="$DNSMASQ_OPTS --local-service"

# If the dns-root-data package is installed, then the trust anchors will be 
# available in $ROOT_DS, in BIND zone-file format. Reformat as dnsmasq
# --trust-anchor options.

ROOT_DS="/usr/share/dns/root.ds"

if [ -f $ROOT_DS ]; then
    DNSMASQ_OPTS="$DNSMASQ_OPTS `env LC_ALL=C sed -rne "s/^([.a-zA-Z0-9]+)([[:space:]]+[0-9]+)*([[:space:]]+IN)*[[:space:]]+DS[[:space:]]+/--trust-anchor=\1,/;s/[[:space:]]+/,/gp" $ROOT_DS | tr '\n' ' '`"
fi

start()
{
        # Return
	#   0 if daemon has been started
	#   1 if daemon was already running
	#   2 if daemon could not be started

        # /run may be volatile, so we need to ensure that
        # /run/dnsmasq exists here as well as in postinst
        if [ ! -d /run/dnsmasq ]; then
           mkdir /run/dnsmasq || return 2
           chown dnsmasq:nogroup /run/dnsmasq || return 2
        fi

	start-stop-daemon --start --quiet --pidfile /run/dnsmasq/$NAME.pid --exec $DAEMON --test > /dev/null || return 1
	start-stop-daemon --start --quiet --pidfile /run/dnsmasq/$NAME.pid --exec $DAEMON -- \
		-x /run/dnsmasq/$NAME.pid \
	        ${MAILHOSTNAME:+ -m $MAILHOSTNAME} \
		${MAILTARGET:+ -t $MAILTARGET} \
		${DNSMASQ_USER:+ -u $DNSMASQ_USER} \
		${DNSMASQ_INTERFACES:+ $DNSMASQ_INTERFACES} \
		${DHCP_LEASE:+ -l $DHCP_LEASE} \
		${DOMAIN_SUFFIX:+ -s $DOMAIN_SUFFIX} \
		${RESOLV_CONF:+ -r $RESOLV_CONF} \
		${CACHESIZE:+ -c $CACHESIZE} \
	        ${CONFIG_DIR:+ -7 $CONFIG_DIR} \
		${DNSMASQ_OPTS:+ $DNSMASQ_OPTS} \
		|| return 2
}

start_resolvconf()
{
# If interface "lo" is explicitly disabled in /etc/default/dnsmasq
# Then dnsmasq won't be providing local DNS, so don't add it to
# the resolvconf server set.
	for interface in $DNSMASQ_EXCEPT
	do
		[ $interface = lo ] && return
	done

# Also skip this if DNS functionality is disabled in /etc/dnsmasq.conf
	if grep -qs '^port=0' /etc/dnsmasq.conf; then
		return
	fi

        if [ -x /sbin/resolvconf ] ; then
		echo "nameserver 127.0.0.1" | /sbin/resolvconf -a lo.$NAME
	fi
	return 0
}

stop()
{
	# Return
	#   0 if daemon has been stopped
	#   1 if daemon was already stopped
	#   2 if daemon could not be stopped
	#   other if a failure occurred
	start-stop-daemon --stop --quiet --retry=TERM/30/KILL/5 --pidfile /run/dnsmasq/$NAME.pid --name $NAME
}

stop_resolvconf()
{
	if [ -x /sbin/resolvconf ] ; then
		/sbin/resolvconf -d lo.$NAME
	fi
	return 0
}

status()
{
	# Return
	#   0 if daemon is running
	#   1 if daemon is dead and pid file exists
	#   3 if daemon is not running
	#   4 if daemon status is unknown
	start-stop-daemon --start --quiet --pidfile /run/dnsmasq/$NAME.pid --exec $DAEMON --test > /dev/null
	case "$?" in
		0) [ -e "/run/dnsmasq/$NAME.pid" ] && return 1 ; return 3 ;;
		1) return 0 ;;
		*) return 4 ;;
	esac
}

case "$1" in
  start)
	test "$ENABLED" != "0" || exit 0
	log_daemon_msg "Starting $DESC" "$NAME"
	start
	case "$?" in
		0)
			log_end_msg 0
			start_resolvconf
			exit 0
			;;
		1)
			log_success_msg "(already running)"
			exit 0
			;;
		*)
			log_end_msg 1
			exit 1
			;;
	esac
	;;
  stop)
	stop_resolvconf
	if [ "$ENABLED" != "0" ]; then
             log_daemon_msg "Stopping $DESC" "$NAME"
	fi
	stop
        RETVAL="$?"
	if [ "$ENABLED" = "0" ]; then
	    case "$RETVAL" in
	       0) log_daemon_msg "Stopping $DESC" "$NAME"; log_end_msg 0 ;;
            esac 
	    exit 0
	fi
	case "$RETVAL" in
		0) log_end_msg 0 ; exit 0 ;;
		1) log_warning_msg "(not running)" ; exit 0 ;;
		*) log_end_msg 1; exit 1 ;;
	esac
	;;
  restart|force-reload)
	test "$ENABLED" != "0" || exit 1
	$DAEMON --test ${CONFIG_DIR:+ -7 $CONFIG_DIR} ${DNSMASQ_OPTS:+ $DNSMASQ_OPTS} >/dev/null 2>&1
	if [ $? -ne 0 ]; then
	    NAME="configuration syntax check"
	    RETVAL="2"
	else   
	    stop_resolvconf
	    stop
	    RETVAL="$?"
        fi
	log_daemon_msg "Restarting $DESC" "$NAME"
	case "$RETVAL" in
		0|1)
		        sleep 2
			start
			case "$?" in
				0)
					log_end_msg 0
					start_resolvconf
					exit 0
					;;
			        *)
					log_end_msg 1
					exit 1
					;;
			esac
			;;
		*)
			log_end_msg 1
			exit 1
			;;
	esac
	;;
  status)
	log_daemon_msg "Checking $DESC" "$NAME"
	status
	case "$?" in
		0) log_success_msg "(running)" ; exit 0 ;;
		1) log_success_msg "(dead, pid file exists)" ; exit 1 ;;
		3) log_success_msg "(not running)" ; exit 3 ;;
		*) log_success_msg "(unknown)" ; exit 4 ;;
	esac
	;;
  dump-stats)
        kill -s USR1 `cat /run/dnsmasq/$NAME.pid`
	;;
  systemd-start-resolvconf)
	start_resolvconf
	;;
  systemd-stop-resolvconf)
	stop_resolvconf
	;;
  systemd-exec)
# /run may be volatile, so we need to ensure that
        # /run/dnsmasq exists here as well as in postinst
        if [ ! -d /run/dnsmasq ]; then
           mkdir /run/dnsmasq || return 2
           chown dnsmasq:nogroup /run/dnsmasq || return 2
        fi
	exec $DAEMON -x /run/dnsmasq/$NAME.pid \
	    ${MAILHOSTNAME:+ -m $MAILHOSTNAME} \
	    ${MAILTARGET:+ -t $MAILTARGET} \
	    ${DNSMASQ_USER:+ -u $DNSMASQ_USER} \
	    ${DNSMASQ_INTERFACES:+ $DNSMASQ_INTERFACES} \
	    ${DHCP_LEASE:+ -l $DHCP_LEASE} \
	    ${DOMAIN_SUFFIX:+ -s $DOMAIN_SUFFIX} \
	    ${RESOLV_CONF:+ -r $RESOLV_CONF} \
	    ${CACHESIZE:+ -c $CACHESIZE} \
	    ${CONFIG_DIR:+ -7 $CONFIG_DIR} \
	    ${DNSMASQ_OPTS:+ $DNSMASQ_OPTS} 
	;;
  *)
	echo "Usage: /etc/init.d/$NAME {start|stop|restart|force-reload|dump-stats|status}" >&2
	exit 3
	;;
esac

exit 0