contrib/openresolv/dnsmasq.in

   1 #!/bin/sh
   2 # Copyright (c) 2007-2023 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 "${dnsmasq_conf}${dnsmasq_resolv}" ] && exit 0
  32 [ -z "$RESOLVCONF" ] && eval "$(@SBINDIR@/resolvconf -v)"
  33 NL="
  34 "
  35
  36 : ${dnsmasq_pid:=/var/run/dnsmasq.pid}
  37 [ -s "$dnsmasq_pid" ] || dnsmasq_pid=/var/run/dnsmasq/dnsmasq.pid
  38 [ -s "$dnsmasq_pid" ] || unset dnsmasq_pid
  39 : ${dnsmasq_service:=dnsmasq}
  40 newconf="# Generated by resolvconf$NL"
  41 newresolv="$newconf"
  42
  43 # Using dbus means that we never have to restart the daemon
  44 # This is important as it means we should not drop DNS queries
  45 # whilst changing DNS options around. However, dbus support is optional
  46 # so we need to validate a few things first.
  47 # Check for DBus support in the binary
  48 dbus=false
  49 dbus_ex=false
  50 dbus_introspect=$(dbus-send --print-reply --system \
  51         --dest=uk.org.thekelleys.dnsmasq \
  52         /uk/org/thekelleys/dnsmasq \
  53         org.freedesktop.DBus.Introspectable.Introspect \
  54         2>/dev/null)
  55 if [ $? = 0 ]; then
  56         dbus=true
  57         if printf %s "$dbus_introspect" | \
  58             grep -q '<method name="SetDomainServers">'
  59         then
  60                 dbus_ex=true
  61         fi
  62 fi
  63
  64 for n in $NAMESERVERS; do
  65         newresolv="${newresolv}nameserver $n$NL"
  66 done
  67
  68 dbusdest=
  69 dbusdest_ex=
  70 conf=
  71 for d in $DOMAINS; do
  72         dn="${d%%:*}"
  73         ns="${d#*:}"
  74         while [ -n "$ns" ]; do
  75                 n="${ns%%,*}"
  76                 if $dbus && ! $dbus_ex; then
  77                         case "$n" in
  78                         *.*.*.*)
  79                                 SIFS=${IFS-y} OIFS=$IFS
  80                                 IFS=.
  81                                 set -- $n
  82                                 num="0x$(printf %02x $1 $2 $3 $4)"
  83                                 if [ "$SIFS" = y ]; then
  84                                         unset IFS
  85                                 else
  86                                         IFS=$OIFS
  87                                 fi
  88                                 dbusdest="$dbusdest uint32:$(printf %u $num)"
  89                                 dbusdest="$dbusdest string:$dn"
  90                                 ;;
  91                         *:*%*)
  92                                 # This version of dnsmasq won't accept
  93                                 # scoped IPv6 addresses
  94                                 dbus=false
  95                                 ;;
  96                         *:*)
  97                                 SIFS=${IFS-y} OIFS=$IFS bytes= front= back=
  98                                 empty=false i=0
  99                                 IFS=:
 100                                 set -- $n
 101                                 while [ -n "$1" ] || [ -n "$2" ]; do
 102                                         addr="$1"
 103                                         shift
 104                                         if [ -z "$addr" ]; then
 105                                                 empty=true
 106                                                 continue
 107                                         fi
 108                                         i=$((i + 1))
 109                                         while [ ${#addr} -lt 4 ]; do
 110                                                 addr="0${addr}"
 111                                         done
 112                                         byte1="$(printf %d 0x${addr%??})"
 113                                         byte2="$(printf %d 0x${addr#??})"
 114                                         if $empty; then
 115                                                 back="$back byte:$byte1 byte:$byte2"
 116                                         else
 117                                                 front="$front byte:$byte1 byte:$byte2"
 118                                         fi
 119                                 done
 120                                 while [ $i != 8 ]; do
 121                                 i=$((i + 1))
 122                                         front="$front byte:0 byte:0"
 123                                 done
 124                                 front="${front}$back"
 125                                 if [ "$SIFS" = y ]; then
 126                                         unset IFS
 127                                 else
 128                                         IFS=$OIFS
 129                                 fi
 130                                 dbusdest="${dbusdest}$front string:$dn"
 131                                 ;;
 132                         *)
 133                                 if ! $dbus_ex; then
 134                                         dbus=false
 135                                 fi
 136                                 ;;
 137                         esac
 138                 fi
 139                 dbusdest_ex="$dbusdest_ex${dbusdest_ex:+,}/$dn/$n"
 140                 conf="${conf}server=/$dn/$n$NL"
 141                 [ "$ns" = "${ns#*,}" ] && break
 142                 ns="${ns#*,}"
 143         done
 144 done
 145
 146 if $dbus; then
 147         newconf="$newconf$NL# Domain specific servers will"
 148         newconf="$newconf be sent over dbus${NL}"
 149 else
 150         newconf="$newconf$conf"
 151 fi
 152
 153 # Try to ensure that config dirs exist
 154 if command -v config_mkdirs >/dev/null 2>&1; then
 155         config_mkdirs "$dnsmasq_conf" "$dnsmasq_resolv"
 156 else
 157         @SBINDIR@/resolvconf -D "$dnsmasq_conf" "$dnsmasq_resolv"
 158 fi
 159
 160 changed=false
 161 if [ -n "$dnsmasq_conf" ]; then
 162         if [ ! -f "$dnsmasq_conf" ] || \
 163                 [ "$(cat "$dnsmasq_conf")" != "$(printf %s "$newconf")" ]
 164         then
 165                 changed=true
 166                 printf %s "$newconf" >"$dnsmasq_conf"
 167         fi
 168 fi
 169 if [ -n "$dnsmasq_resolv" ]; then
 170         # dnsmasq polls this file so no need to set changed=true
 171         if [ -f "$dnsmasq_resolv" ]; then
 172                 if [ "$(cat "$dnsmasq_resolv")" != "$(printf %s "$newresolv")" ]
 173                 then
 174                         printf %s "$newresolv" >"$dnsmasq_resolv"
 175                 fi
 176         else
 177                 printf %s "$newresolv" >"$dnsmasq_resolv"
 178         fi
 179 fi
 180
 181 if $changed; then
 182         # dnsmasq does not re-read the configuration file on SIGHUP
 183         if [ -n "$dnsmasq_restart" ]; then
 184                 eval $dnsmasq_restart
 185         elif [ -n "$RESTARTCMD" ]; then
 186                 set -- ${dnsmasq_service}
 187                 eval "$RESTARTCMD"
 188         else
 189                 @SBINDIR@/resolvconf -r ${dnsmasq_service}
 190         fi
 191 fi
 192 if $dbus; then
 193         if [ -s "$dnsmasq_pid" ]; then
 194                 $changed || kill -HUP $(cat "$dnsmasq_pid")
 195         fi
 196         # Send even if empty so old servers are cleared
 197         if $dbus_ex; then
 198                 method=SetDomainServers
 199                 if [ -n "$dbusdest_ex" ]; then
 200                         dbusdest_ex="array:string:$dbusdest_ex"
 201                 fi
 202                 dbusdest="$dbusdest_ex"
 203         else
 204                 method=SetServers
 205         fi
 206         dbus-send --system --dest=uk.org.thekelleys.dnsmasq \
 207                 /uk/org/thekelleys/dnsmasq uk.org.thekelleys.$method \
 208                 $dbusdest
 209         dbus-send --system --dest=uk.org.thekelleys.dnsmasq \
 210                 /uk/org/thekelleys/dnsmasq uk.org.thekelleys.ClearCache
 211 fi