roy.marples.name Git - openresolv/blob - 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) continue;;
 112                 *) newns="$newns${newns:+ }$n"
 113                 esac
 114         done
 115         echo "NAMESERVERS=\"$newns\""
 116         newns=
 117
 118         while read line; do
 119                 case "$line" in
 120                 "# resolv.conf from "*)
 121                         if ${new}; then
 122                                 iface="${line#\# resolv.conf from *}"
 123                                 new=false
 124                                 if [ -e "$PRIVATEDIR/$iface" ]; then
 125                                         private=true
 126                                 else
 127                                         # Allow expansion
 128                                         cd "$IFACEDIR"
 129                                         private=false
 130                                         for p in $private_interfaces; do
 131                                                 if [ "$p" = "$iface" ]; then
 132                                                         private=true
 133                                                         break
 134                                                 fi
 135                                         done
 136                                 fi
 137                         fi
 138                         ;;
 139                 "nameserver "*)
 140                         case "${line#* }" in
 141                         127.*|0.0.0.0|255.255.255.255|::1) continue;;
 142                         esac
 143                         ns="$ns${line#* } "
 144                         ;;
 145                 "domain "*|"search "*)
 146                         search="${line#* }"
 147                         ;;
 148                 *)
 149                         [ -n "$line" ] && continue
 150                         if [ -n "$ns" -a -n "$search" ]; then
 151                                 newns=
 152                                 for n in $ns; do
 153                                         newns="$newns${newns:+,}$n"
 154                                 done
 155                                 ds=
 156                                 for d in $search; do
 157                                         ds="$ds${ds:+ }$d:$newns"
 158                                 done
 159                                 echo "DOMAINS=\"\$DOMAINS $ds\""
 160                         fi
 161                         echo "SEARCH=\"\$SEARCH $search\""
 162                         if ! $private; then
 163                                 echo "NAMESERVERS=\"\$NAMESERVERS $ns\""
 164                         fi
 165                         ns=
 166                         search=
 167                         new=true
 168                         ;;
 169                 esac
 170         done
 171 }
 172
 173 uniqify()
 174 {
 175         local result=
 176         while [ -n "$1" ]; do
 177                 case " $result " in
 178                 *" $1 "*);;
 179                 *) result="$result $1";;
 180                 esac
 181                 shift
 182         done
 183         echo "${result# *}"
 184 }
 185
 186 list_resolv()
 187 {
 188         [ -d "$IFACEDIR" ] || return 0
 189
 190         local report=false list= retval=0 cmd="$1"
 191         shift
 192
 193         # If we have an interface ordering list, then use that.
 194         # It works by just using pathname expansion in the interface directory.
 195         if [ -n "$1" ]; then
 196                 list="$@"
 197                 $force || report=true
 198         else
 199                 cd "$IFACEDIR"
 200                 for i in $interface_order; do
 201                         [ -e "$i" ] && list="$list $i"
 202                 done
 203                 for i in $dynamic_order; do
 204                         if [ -e "$i" -a ! -e "$METRICDIR/"*" $i" ]; then
 205                                 list="$list $i"
 206                         fi
 207                 done
 208                 if [ -d "$METRICDIR" ]; then
 209                         cd "$METRICDIR"
 210                         for i in *; do
 211                                 list="$list ${i#* }"
 212                         done
 213                 fi
 214                 list="$list *"
 215         fi
 216
 217         cd "$IFACEDIR"
 218         for i in $(uniqify $list); do
 219                 # Only list interfaces which we really have
 220                 if ! [ -e "$i" ]; then
 221                         if $report; then
 222                                 echo "No resolv.conf for interface $i" >&2
 223                                 retval=$(($retval + 1))
 224                         fi
 225                         continue
 226                 fi
 227
 228                 if [ "$cmd" = i -o "$cmd" = "-i" ]; then
 229                         printf "$i "
 230                 else
 231                         echo_resolv "$i"
 232                 fi
 233         done
 234         [ "$cmd" = i -o "$cmd" = "-i" ] && echo
 235         return $retval
 236 }
 237
 238 make_vars()
 239 {
 240         eval "$(list_resolv -l "$@" | parse_resolv)"
 241
 242         # Ensure that we only list each domain once
 243         newdomains=
 244         for d in $DOMAINS; do
 245                 dn="${d%%:*}"
 246                 case " $newdomains" in
 247                 *" ${dn}:"*) continue;;
 248                 esac
 249                 newdomains="$newdomains${newdomains:+ }$dn:"
 250                 newns=
 251                 for nd in $DOMAINS; do
 252                         if [ "$dn" = "${nd%%:*}" ]; then
 253                                 ns="${nd#*:}"
 254                                 while [ -n "$ns" ]; do
 255                                         case ",$newns," in
 256                                         *,${ns%%,*},*) ;;
 257                                         *) newns="$newns${newns:+,}${ns%%,*}";;
 258                                         esac
 259                                         [ "$ns" = "${ns#*,}" ] && break
 260                                         ns="${ns#*,}"
 261                                 done
 262                         fi
 263                 done
 264                 newdomains="$newdomains$newns"
 265         done
 266         echo "DOMAINS='$newdomains'"
 267         echo "SEARCH='$(uniqify $SEARCH)'"
 268         echo "NAMESERVERS='$(uniqify $NAMESERVERS)'"
 269 }
 270
 271 force=false
 272 while getopts a:d:fhilm:puv OPT; do
 273         case "$OPT" in
 274         f) force=true;;
 275         h) usage;;
 276         m) IF_METRIC="$OPTARG";;
 277         p) IF_PRIVATE=1;;
 278         '?') ;;
 279         *) cmd="$OPT"; iface="$OPTARG";;
 280         esac
 281 done
 282 shift $(($OPTIND - 1))
 283 args="$iface${iface:+ }$@"
 284
 285 # -I inits the state dir
 286 if [ "$cmd" = I ]; then
 287         if [ -d "$VARDIR" ]; then
 288                 rm -rf "$VARDIR"/*
 289         fi
 290         exit $?
 291 fi
 292
 293 # -l lists our resolv files, optionally for a specific interface
 294 if [ "$cmd" = l -o "$cmd" = i ]; then
 295         list_resolv "$cmd" "$args"
 296         exit $?
 297 fi
 298
 299 # Not normally needed, but subscribers should be able to run independently
 300 if [ "$cmd" = v ]; then
 301         make_vars "$iface"
 302         exit $?
 303 fi
 304
 305 # Test that we have valid options
 306 if [ "$cmd" = a -o "$cmd" = d ]; then
 307         if [ -z "$iface" ]; then
 308                 usage "Interface not specified"
 309         fi
 310 elif [ "$cmd" != u ]; then
 311         [ -n "$cmd" -a "$cmd" != h ] && usage "Unknown option $cmd"
 312         usage
 313 fi
 314 if [ "$cmd" = a ]; then
 315         for x in '/' \\ ' ' '*'; do
 316                 case "$iface" in
 317                 *[$x]*) error_exit "$x not allowed in interface name";;
 318                 esac
 319         done
 320         for x in '.' '-' '~'; do
 321                 case "$iface" in
 322                 [$x]*) error_exit \
 323                         "$x not allowed at start of interface name";;
 324                 esac
 325         done
 326         [ "$cmd" = a -a -t 0 ] && error_exit "No file given via stdin"
 327 fi
 328
 329 if [ ! -d "$IFACEDIR" ]; then
 330         if [ ! -d "$VARDIR" ]; then
 331                 if [ -L "$VARDIR" ]; then
 332                         dir="$(readlink "$VARDIR")"
 333                         # link maybe relative
 334                         cd "${VARDIR%/*}"
 335                         if ! mkdir -m 0755 -p "$dir"; then
 336                                 error_exit "Failed to create needed" \
 337                                         "directory $dir"
 338                         fi
 339                 else
 340                         if ! mkdir -m 0755 -p "$VARDIR"; then
 341                                 error_exit "Failed to create needed" \
 342                                         "directory $VARDIR"
 343                         fi
 344                 fi
 345         fi
 346         mkdir -m 0755 -p "$IFACEDIR" || \
 347                 error_exit "Failed to create needed directory $IFACEDIR"
 348 else
 349         # Delete any existing information about the interface
 350         if [ "$cmd" = d ]; then
 351                 cd "$IFACEDIR"
 352                 for i in $args; do
 353                         if [ "$cmd" = d -a ! -e "$i" ]; then
 354                                 $force && continue
 355                                 error_exit "No resolv.conf for" \
 356                                         "interface $i"
 357                         fi
 358                         rm -f "$i" "$METRICDIR/"*" $i" \
 359                                 "$PRIVATEDIR/$i" || exit $?
 360                 done
 361         fi
 362 fi
 363
 364 if [ "$cmd" = a ]; then
 365         # Read resolv.conf from stdin
 366         resolv="$(cat)\n"
 367         # If what we are given matches what we have, then do nothing
 368         if [ -e "$IFACEDIR/$iface" ]; then
 369                 if [ "$(printf "$resolv")" = \
 370                         "$(cat "$IFACEDIR/$iface")" ]
 371                 then
 372                         exit 0
 373                 fi
 374                 rm "$IFACEDIR/$iface"
 375         fi
 376         printf "$resolv" >"$IFACEDIR/$iface" || exit $?
 377         [ ! -d "$METRICDIR" ] && mkdir "$METRICDIR"
 378         rm -f "$METRICDIR/"*" $iface"
 379         if [ -n "$IF_METRIC" ]; then
 380                 # Pad metric to 6 characters, so 5 is less than 10
 381                 while [ ${#IF_METRIC} -le 6 ]; do
 382                         IF_METRIC="0$IF_METRIC"
 383                 done
 384                 echo " " >"$METRICDIR/$IF_METRIC $iface"
 385         fi
 386         case "$IF_PRIVATE" in
 387         [Yy][Ee][Ss]|[Tt][Rr][Uu][Ee]|[Oo][Nn]|1)
 388                 if [ ! -d "$PRIVATEDIR" ]; then
 389                         [ -e "$PRIVATEDIR" ] && rm "$PRIVATEDIR"
 390                         mkdir "$PRIVATEDIR"
 391                 fi
 392                 [ -d "$PRIVATEDIR" ] && echo " " >"$PRIVATEDIR/$iface"
 393                 ;;
 394         *)
 395                 if [ -e "$PRIVATEDIR/$iface" ]; then
 396                         rm -f "$PRIVATEDIR/$iface"
 397                 fi
 398                 ;;
 399         esac
 400 fi
 401
 402 eval "$(make_vars)"
 403 export RESOLVCONF DOMAINS SEARCH NAMESERVERS
 404 : ${list_resolv:=list_resolv -l}
 405 retval=0
 406 for script in "$LIBEXECDIR"/*; do
 407         if [ -f "$script" ]; then
 408                 if [ -x "$script" ]; then
 409                         "$script" "$cmd" "$iface"
 410                 else
 411                         (. "$script" "$cmd" "$iface")
 412                 fi
 413                 retval=$(($retval + $?))
 414         fi
 415 done
 416 exit $retval