contrib/openresolv/resolvconf.in

   1 #!/bin/sh
   2 # Copyright (c) 2007-2009 Roy Marples
   3 # All rights reserved
   4
   5 # Redistribution and use in source and binary forms, with or without
   6 # modification, are permitted provided that the following conditions
   7 # are met:
   8 #     * Redistributions of source code must retain the above copyright
   9 #       notice, this list of conditions and the following disclaimer.
  10 #     * Redistributions in binary form must reproduce the above
  11 #       copyright notice, this list of conditions and the following
  12 #       disclaimer in the documentation and/or other materials provided
  13 #       with the distribution.
  14 #
  15 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  16 # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  17 # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  18 # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  19 # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  20 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  21 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  25 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26
  27 RESOLVCONF="$0"
  28 SYSCONFDIR=@SYSCONFDIR@
  29 LIBEXECDIR=@LIBEXECDIR@
  30 VARDIR=@VARDIR@
  31 # Support original resolvconf configuration layout
  32 # as well as the openresolv config file
  33 if [ -f "$SYSCONFDIR"/resolvconf.conf ]; then
  34         . "$SYSCONFDIR"/resolvconf.conf
  35         [ -n "$state_dir" ] && VARDIR="$state_dir"
  36 elif [ -d "$SYSCONFDIR/resolvconf" ]; then
  37         SYSCONFDIR="$SYSCONFDIR/resolvconf"
  38         if [ -f "$SYSCONFDIR"/interface-order ]; then
  39                 interface_order="$(cat "$SYSCONFDIR"/interface-order)"
  40         fi
  41 fi
  42 IFACEDIR="$VARDIR/interfaces"
  43 METRICDIR="$VARDIR/metrics"
  44 PRIVATEDIR="$VARDIR/private"
  45
  46 : ${dynamic_order:=tap[0-9]* tun[0-9]* vpn vpn[0-9]* ppp[0-9]* ippp[0-9]*}
  47 : ${interface_order:=lo lo[0-9]*}
  48
  49 error_exit()
  50 {
  51         echo "$*" >&2
  52         exit 1
  53 }
  54
  55 usage()
  56 {
  57         cat <<-EOF
  58         Usage: ${RESOLVCONF##*/} [options]
  59
  60         Inform the system about any DNS updates.
  61
  62         Options:
  63           -a \$INTERFACE    Add DNS information to the specified interface
  64                            (DNS supplied via stdin in resolv.conf format)
  65           -m metric        Give the added DNS information a metric
  66           -p               Mark the interface as private
  67           -d \$INTERFACE    Delete DNS information from the specified interface
  68           -f               Ignore non existant interfaces
  69           -I               Init the state dir
  70           -u               Run updates from our current DNS information
  71           -l [\$PATTERN]    Show DNS information, optionally from interfaces
  72                            that match the specified pattern
  73           -i [\$PATTERN]    Show interfaces that have supplied DNS information
  74                    optionally from interfaces that match the specified
  75                    pattern
  76           -v [\$PATTERN]    echo NEWDOMAIN, NEWSEARCH and NEWNS variables to
  77                            the console
  78           -h               Show this help cruft
  79         EOF
  80         [ -z "$1" ] && exit 0
  81         echo
  82         error_exit "$*"
  83 }
  84
  85 echo_resolv()
  86 {
  87         local line=
  88         [ -n "$1" -a -e "$IFACEDIR/$1" ] || return 1
  89         echo "# resolv.conf from $1"
  90         # Our variable maker works of the fact each resolv.conf per interface
  91         # is separated by blank lines.
  92         # So we remove them when echoing them.
  93         while read line; do
  94                 [ -n "$line" ] && echo "$line"
  95         done < "$IFACEDIR/$1"
  96         echo
  97 }
  98
  99 # Parse resolv.conf's and make variables
 100 # for domain name servers, search name servers and global nameservers
 101 parse_resolv()
 102 {
 103         local line= ns= ds= search= d= n= newns=
 104         local new=true iface= private=false p=
 105
 106         echo "DOMAINS="
 107         echo "SEARCH=\"$search_domains\""
 108         # let our subscribers know about global nameservers
 109         for n in $name_servers; do
 110                 case "$n" in
 111                 127.*|0.0.0.0|255.255.255.255|::1) :;;
 112                 *) newns="$newns${newns:+ }$n";;
 113                 esac
 114         done
 115         echo "NAMESERVERS=\"$newns\""
 116         echo "LOCALNAMESERVERS="
 117         newns=
 118
 119         while read line; do
 120                 case "$line" in
 121                 "# resolv.conf from "*)
 122                         if ${new}; then
 123                                 iface="${line#\# resolv.conf from *}"
 124                                 new=false
 125                                 if [ -e "$PRIVATEDIR/$iface" ]; then
 126                                         private=true
 127                                 else
 128                                         # Allow expansion
 129                                         cd "$IFACEDIR"
 130                                         private=false
 131                                         for p in $private_interfaces; do
 132                                                 if [ "$p" = "$iface" ]; then
 133                                                         private=true
 134                                                         break
 135                                                 fi
 136                                         done
 137                                 fi
 138                         fi
 139                         ;;
 140                 "nameserver "*)
 141                         case "${line#* }" in
 142                         127.*|0.0.0.0|255.255.255.255|::1)
 143                                 echo "LOCALNAMESERVERS=\"\$LOCALNAMESERVERS ${line#* }\""
 144                                 continue
 145                                 ;;
 146                         esac
 147                         ns="$ns${line#* } "
 148                         ;;
 149                 "domain "*|"search "*)
 150                         search="${line#* }"
 151                         ;;
 152                 *)
 153                         [ -n "$line" ] && continue
 154                         if [ -n "$ns" -a -n "$search" ]; then
 155                                 newns=
 156                                 for n in $ns; do
 157                                         newns="$newns${newns:+,}$n"
 158                                 done
 159                                 ds=
 160                                 for d in $search; do
 161                                         ds="$ds${ds:+ }$d:$newns"
 162                                 done
 163                                 echo "DOMAINS=\"\$DOMAINS $ds\""
 164                         fi
 165                         echo "SEARCH=\"\$SEARCH $search\""
 166                         if ! $private; then
 167                                 echo "NAMESERVERS=\"\$NAMESERVERS $ns\""
 168                         fi
 169                         ns=
 170                         search=
 171                         new=true
 172                         ;;
 173                 esac
 174         done
 175 }
 176
 177 uniqify()
 178 {
 179         local result=
 180         while [ -n "$1" ]; do
 181                 case " $result " in
 182                 *" $1 "*);;
 183                 *) result="$result $1";;
 184                 esac
 185                 shift
 186         done
 187         echo "${result# *}"
 188 }
 189
 190 list_resolv()
 191 {
 192         [ -d "$IFACEDIR" ] || return 0
 193
 194         local report=false list= retval=0 cmd="$1"
 195         shift
 196
 197         # If we have an interface ordering list, then use that.
 198         # It works by just using pathname expansion in the interface directory.
 199         if [ -n "$1" ]; then
 200                 list="$@"
 201                 $force || report=true
 202         else
 203                 cd "$IFACEDIR"
 204                 for i in $interface_order; do
 205                         [ -e "$i" ] && list="$list $i"
 206                 done
 207                 for i in $dynamic_order; do
 208                         if [ -e "$i" -a ! -e "$METRICDIR/"*" $i" ]; then
 209                                 list="$list $i"
 210                         fi
 211                 done
 212                 if [ -d "$METRICDIR" ]; then
 213                         cd "$METRICDIR"
 214                         for i in *; do
 215                                 list="$list ${i#* }"
 216                         done
 217                 fi
 218                 list="$list *"
 219         fi
 220
 221         cd "$IFACEDIR"
 222         for i in $(uniqify $list); do
 223                 # Only list interfaces which we really have
 224                 if ! [ -e "$i" ]; then
 225                         if $report; then
 226                                 echo "No resolv.conf for interface $i" >&2
 227                                 retval=$(($retval + 1))
 228                         fi
 229                         continue
 230                 fi
 231
 232                 if [ "$cmd" = i -o "$cmd" = "-i" ]; then
 233                         printf "$i "
 234                 else
 235                         echo_resolv "$i"
 236                 fi
 237         done
 238         [ "$cmd" = i -o "$cmd" = "-i" ] && echo
 239         return $retval
 240 }
 241
 242 make_vars()
 243 {
 244         eval "$(list_resolv -l "$@" | parse_resolv)"
 245
 246         # Ensure that we only list each domain once
 247         newdomains=
 248         for d in $DOMAINS; do
 249                 dn="${d%%:*}"
 250                 case " $newdomains" in
 251                 *" ${dn}:"*) continue;;
 252                 esac
 253                 newdomains="$newdomains${newdomains:+ }$dn:"
 254                 newns=
 255                 for nd in $DOMAINS; do
 256                         if [ "$dn" = "${nd%%:*}" ]; then
 257                                 ns="${nd#*:}"
 258                                 while [ -n "$ns" ]; do
 259                                         case ",$newns," in
 260                                         *,${ns%%,*},*) ;;
 261                                         *) newns="$newns${newns:+,}${ns%%,*}";;
 262                                         esac
 263                                         [ "$ns" = "${ns#*,}" ] && break
 264                                         ns="${ns#*,}"
 265                                 done
 266                         fi
 267                 done
 268                 newdomains="$newdomains$newns"
 269         done
 270         echo "DOMAINS='$newdomains'"
 271         echo "SEARCH='$(uniqify $SEARCH)'"
 272         echo "NAMESERVERS='$(uniqify $NAMESERVERS)'"
 273         echo "LOCALNAMESERVERS='$(uniqify $LOCALNAMESERVERS)'"
 274 }
 275
 276 force=false
 277 while getopts a:d:fhIilm:puv OPT; do
 278         case "$OPT" in
 279         f) force=true;;
 280         h) usage;;
 281         m) IF_METRIC="$OPTARG";;
 282         p) IF_PRIVATE=1;;
 283         '?') ;;
 284         *) cmd="$OPT"; iface="$OPTARG";;
 285         esac
 286 done
 287 shift $(($OPTIND - 1))
 288 args="$iface${iface:+ }$@"
 289
 290 # -I inits the state dir
 291 if [ "$cmd" = I ]; then
 292         if [ -d "$VARDIR" ]; then
 293                 rm -rf "$VARDIR"/*
 294         fi
 295         exit $?
 296 fi
 297
 298 # -l lists our resolv files, optionally for a specific interface
 299 if [ "$cmd" = l -o "$cmd" = i ]; then
 300         list_resolv "$cmd" "$args"
 301         exit $?
 302 fi
 303
 304 # Not normally needed, but subscribers should be able to run independently
 305 if [ "$cmd" = v ]; then
 306         make_vars "$iface"
 307         exit $?
 308 fi
 309
 310 # Test that we have valid options
 311 if [ "$cmd" = a -o "$cmd" = d ]; then
 312         if [ -z "$iface" ]; then
 313                 usage "Interface not specified"
 314         fi
 315 elif [ "$cmd" != u ]; then
 316         [ -n "$cmd" -a "$cmd" != h ] && usage "Unknown option $cmd"
 317         usage
 318 fi
 319 if [ "$cmd" = a ]; then
 320         for x in '/' \\ ' ' '*'; do
 321                 case "$iface" in
 322                 *[$x]*) error_exit "$x not allowed in interface name";;
 323                 esac
 324         done
 325         for x in '.' '-' '~'; do
 326                 case "$iface" in
 327                 [$x]*) error_exit \
 328                         "$x not allowed at start of interface name";;
 329                 esac
 330         done
 331         [ "$cmd" = a -a -t 0 ] && error_exit "No file given via stdin"
 332 fi
 333
 334 if [ ! -d "$IFACEDIR" ]; then
 335         if [ ! -d "$VARDIR" ]; then
 336                 if [ -L "$VARDIR" ]; then
 337                         dir="$(readlink "$VARDIR")"
 338                         # link maybe relative
 339                         cd "${VARDIR%/*}"
 340                         if ! mkdir -m 0755 -p "$dir"; then
 341                                 error_exit "Failed to create needed" \
 342                                         "directory $dir"
 343                         fi
 344                 else
 345                         if ! mkdir -m 0755 -p "$VARDIR"; then
 346                                 error_exit "Failed to create needed" \
 347                                         "directory $VARDIR"
 348                         fi
 349                 fi
 350         fi
 351         mkdir -m 0755 -p "$IFACEDIR" || \
 352                 error_exit "Failed to create needed directory $IFACEDIR"
 353 else
 354         # Delete any existing information about the interface
 355         if [ "$cmd" = d ]; then
 356                 cd "$IFACEDIR"
 357                 for i in $args; do
 358                         if [ "$cmd" = d -a ! -e "$i" ]; then
 359                                 $force && continue
 360                                 error_exit "No resolv.conf for" \
 361                                         "interface $i"
 362                         fi
 363                         rm -f "$i" "$METRICDIR/"*" $i" \
 364                                 "$PRIVATEDIR/$i" || exit $?
 365                 done
 366         fi
 367 fi
 368
 369 if [ "$cmd" = a ]; then
 370         # Read resolv.conf from stdin
 371         resolv="$(cat)"
 372         # If what we are given matches what we have, then do nothing
 373         if [ -e "$IFACEDIR/$iface" ]; then
 374                 if [ "$(echo "$resolv")" = \
 375                         "$(cat "$IFACEDIR/$iface")" ]
 376                 then
 377                         exit 0
 378                 fi
 379                 rm "$IFACEDIR/$iface"
 380         fi
 381         echo "$resolv" >"$IFACEDIR/$iface" || exit $?
 382         [ ! -d "$METRICDIR" ] && mkdir "$METRICDIR"
 383         rm -f "$METRICDIR/"*" $iface"
 384         if [ -n "$IF_METRIC" ]; then
 385                 # Pad metric to 6 characters, so 5 is less than 10
 386                 while [ ${#IF_METRIC} -le 6 ]; do
 387                         IF_METRIC="0$IF_METRIC"
 388                 done
 389                 echo " " >"$METRICDIR/$IF_METRIC $iface"
 390         fi
 391         case "$IF_PRIVATE" in
 392         [Yy][Ee][Ss]|[Tt][Rr][Uu][Ee]|[Oo][Nn]|1)
 393                 if [ ! -d "$PRIVATEDIR" ]; then
 394                         [ -e "$PRIVATEDIR" ] && rm "$PRIVATEDIR"
 395                         mkdir "$PRIVATEDIR"
 396                 fi
 397                 [ -d "$PRIVATEDIR" ] && echo " " >"$PRIVATEDIR/$iface"
 398                 ;;
 399         *)
 400                 if [ -e "$PRIVATEDIR/$iface" ]; then
 401                         rm -f "$PRIVATEDIR/$iface"
 402                 fi
 403                 ;;
 404         esac
 405 fi
 406
 407 eval "$(make_vars)"
 408 export RESOLVCONF DOMAINS SEARCH NAMESERVERS LOCALNAMESERVERS
 409 : ${list_resolv:=list_resolv -l}
 410 retval=0
 411 for script in "$LIBEXECDIR"/*; do
 412         if [ -f "$script" ]; then
 413                 if [ -x "$script" ]; then
 414                         "$script" "$cmd" "$iface"
 415                 else
 416                         (. "$script" "$cmd" "$iface")
 417                 fi
 418                 retval=$(($retval + $?))
 419         fi
 420 done
 421 exit $retval