/contrib/openresolv/dnsmasq.in

  1#!/bin/sh
  2# Copyright (c) 2007-2009 Roy Marples
  3# All rights reserved
  4
  5# dnsmasq subscriber for resolvconf
  6
  7# Redistribution and use in source and binary forms, with or without
  8# modification, are permitted provided that the following conditions
  9# are met:
 10#     * Redistributions of source code must retain the above copyright
 11#       notice, this list of conditions and the following disclaimer.
 12#     * Redistributions in binary form must reproduce the above
 13#       copyright notice, this list of conditions and the following
 14#       disclaimer in the documentation and/or other materials provided
 15#       with the distribution.
 16#
 17# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 18# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 19# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 20# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 21# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 22# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 23# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 24# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 25# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 26# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 27# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 28
 29[ -f "@SYSCONFDIR@"/resolvconf.conf ] || exit 0
 30. "@SYSCONFDIR@/resolvconf.conf" || exit 1
 31[ -z "$dnsmasq_conf" -a -z "$dnsmasq_resolv" ] && exit 0
 32[ -z "$RESOLVCONF" ] && eval "$(@PREFIX@/sbin/resolvconf -v)"
 33NL="
 34"
 35
 36: ${dnsmasq_pid:=/var/run/dnsmasq.pid}
 37[ -s "$dnsmasq_pid" ] || dnsmasq_pid=/var/run/dnsmasq/dnsmasq.pid
 38: ${dnsmasq_service:=dnsmasq}
 39: ${dnsmasq_restart:=@RESTARTCMD ${dnsmasq_service}@}
 40newconf="# Generated by resolvconf$NL"
 41newresolv="$newconf"
 42
 43# Using dbus means that we never have to restart the daemon
 44# This is important as it means we should not drop DNS queries
 45# whilst changing DNS options around. However, dbus support is optional
 46# so we need to validate a few things first.
 47# Check for DBus support in the binary
 48dbus=false
 49: ${dbus_pid:=/var/run/dbus/dbus.pid}
 50[ -s "$dbus_pid" ] || dbus_pid=/var/run/dbus.pid
 51[ -s "$dbus_pid" ] || dbus_pid=/var/run/dbus/pid
 52if [ -s "$dbus_pid" -a -s "$dnsmasq_pid" ]; then
 53	if dnsmasq --version 2>/dev/null | \
 54		grep -q "^Compile time options.*[[:space:]]DBus[[:space:]]"
 55	then
 56		# Sanity - check that dnsmasq and dbus are running
 57		if kill -0 $(cat "$dbus_pid") 2>/dev/null && \
 58			kill -0 $(cat "$dnsmasq_pid") 2>/dev/null
 59		then
 60			dbus=true
 61			newconf="$newconf$NL# Domain specific servers will"
 62			newconf="$newconf be sent over dbus${NL}enable-dbus$NL"
 63		fi
 64	fi
 65fi
 66
 67for n in $NAMESERVERS; do
 68	newresolv="${newresolv}nameserver $n$NL"
 69done
 70
 71dbusdest=
 72for d in $DOMAINS; do
 73	dn="${d%%:*}"
 74	ns="${d#*:}"
 75	while [ -n "$ns" ]; do
 76		if $dbus; then
 77			SIFS=${IFS-y} OIFS=$IFS
 78			IFS=.
 79			set -- ${ns%%,*}
 80			num="0x$(printf %02x $1 $2 $3 $4)"
 81			if [ "$SIFS" = yi ]; then
 82				unset IFS
 83			else
 84				IFS=$OIFS
 85			fi
 86			dbusdest="$dbusdest uint32:$(printf %u $num)"
 87			dbusdest="$dbusdest string:$dn"
 88		else
 89			newconf="${newconf}server=/$dn/${ns%%,*}$NL"
 90		fi
 91		[ "$ns" = "${ns#*,}" ] && break
 92		ns="${ns#*,}"
 93	done
 94done
 95
 96changed=false
 97if [ -n "$dnsmasq_conf" ]; then
 98	if [ ! -f "$dnsmasq_conf" ] || \
 99		[ "$(cat "$dnsmasq_conf")" != "$(printf %s "$newconf")" ]
100	then
101		changed=true
102		printf %s "$newconf" >"$dnsmasq_conf"
103	fi
104fi
105if [ -n "$dnsmasq_resolv" ]; then
106	if [ -f "$dnsmasq_resolv" ]; then
107		if [ "$(cat "$dnsmasq_resolv")" != "$(printf %s "$newresolv")" ]
108		then
109			changed=true
110			printf %s "$newresolv" >"$dnsmasq_resolv"
111		fi
112	else
113		# dnsmasq polls this file so no need to set changed=true
114		printf %s "$newresolv" >"$dnsmasq_resolv"
115	fi
116fi
117
118if $changed; then
119	eval $dnsmasq_restart
120fi
121if $dbus; then
122	$changed || kill -HUP $(cat "$dnsmasq_pid")
123	# Send even if empty so old servers are cleared
124	dbus-send --system --dest=uk.org.thekelleys.dnsmasq \
125 		/uk/org/thekelleys/dnsmasq uk.org.thekelleys.SetServers \
126  		$dbusdest
127fi