roy.marples.name Git - openresolv/blob - resolvconf.in

   1 #!/bin/sh
   2 # Copyright 2007 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 argv0="$0"
  28
  29 PREFIX=
  30 RESOLVCONF="${PREFIX}"/etc/resolvconf
  31 UPDATED="${RESOLVCONF}"/update.d
  32 VARDIR="${RESOLVCONF}"/run
  33 IFACEDIR="${VARDIR}/interfaces"
  34
  35 error_exit() {
  36         echo "$*" >&2
  37         exit 1
  38 }
  39
  40 usage() {
  41         cat <<-EOF
  42         Usage: ${argv0##*/} [options]
  43
  44         Inform the system about any DNS updates.
  45
  46         Options:
  47           -a \$INTERFACE    Add DNS information to the specified interface
  48                            (DNS supplied via stdin in resolv.conf format)
  49           -d \$INTERFACE    Delete DNS information from the specified interface
  50           -u               Run updates from our current DNS information
  51           -l [\$PATTERN]    Show DNS information, optionally from interfaces
  52                            that match the specified pattern
  53           -i [\$PATTERN]    Show interfaces that have supplied DNS information
  54                    optionally from interfaces that match the specified
  55                    pattern
  56           -v [\$PATTERN]    echo NEWDOMAIN, NEWSEARCH and NEWNS variables to
  57                            the console
  58           -s \$SVC \$CMD     Do \$CMD for the system service \$SVC
  59           -h               Show this help cruft
  60         EOF
  61         [ -z "$@" ] && exit 0
  62         echo
  63         error_exit "$*"
  64 }
  65
  66 echo_resolv() {
  67         [ -n "$1" -a -e "${IFACEDIR}/$1" ] || return 1
  68         echo "# resolv.conf for interface $1"
  69         cat "${IFACEDIR}/$1"
  70         echo
  71 }
  72
  73 uniqify() {
  74     local result=
  75     while [ -n "$1" ]; do
  76                 case " ${result} " in
  77                         *" $1 "*);;
  78                         *) result="${result} $1";;
  79                 esac
  80                 shift
  81         done
  82     echo "${result# *}"
  83 }
  84
  85 if [ -n "$1" ]; then
  86         CMD="$1"
  87         shift
  88 fi
  89
  90 # We do our service restarting here so that our subscribers don't have to know
  91 # about the OS's init system.
  92 if [ "x${CMD}" = "x-s" ]; then
  93         if [ -n "$1" ]; then
  94                 SERVICE="$1"
  95                 shift
  96         fi
  97         [ -z "${SERVICE}" ] && usage "Service not specified"
  98         if [ -n "$1" ]; then
  99                 ACTION="$1"
 100                 shift
 101         fi
 102         [ -z "${ACTION}" ] && usage "Action not specified"
 103
 104         # If restarting check if service is running or not if we can
 105         if [ "x${ACTION}" = "xrestart" ]; then
 106                 if [ -s /var/run/"${SERVICE}".pid ]; then
 107                         kill -0 $(cat /var/run/"${SERVICE}".pid)
 108                 elif [ -s /var/run/"${SERVICE}"/"${SERVICE}".pid ]; then
 109                         kill -0 $(cat /var/run/"${SERVICE}".pid)
 110                 elif [ -s /var/run/"${SERVICE}"/pid ]; then
 111                         kill -0 $(cat /var/run/"${SERVICE}"/pid)
 112                 else
 113                         false
 114                 fi
 115                 # Service not running, so don't restart
 116                 [ $? != 0 ] && exit 1
 117         fi
 118         if [ -x /sbin/service ]; then
 119                 service "${SERVICE}" "${ACTION}" "$@"
 120         elif [ -x /etc/init.d/"${SERVICE}" -a -x /sbin/runscript ]; then
 121                 if [ "x${ACTION}" = "xrestart" ]; then
 122                         /etc/init.d/"${SERVICE}" --quiet --nodeps conditionalrestart "$@"
 123                 else
 124                         /etc/init.d/"${SERVICE}" --quiet --nodeps "${ACTION}" "$@"
 125                 fi
 126         elif [ -x /etc/init.d/"${SERVICE}" ]; then
 127                 /etc/init.d/"${SERVICE}" "${ACTION}" "$@"
 128         elif [ -x /etc/rc.d/"${SERVICE}" ]; then
 129                 /etc/rc.d/"${SERVICE}" "${ACTION}" "$@"
 130         elif [ -x /etc/rc.d/rc."${SERVICE}" ]; then
 131                 /etc/rc.d/rc."${SERVICE}" "${ACTION}" "$@"
 132         else
 133                 error_exit "Don't know how to interact with services on this platform"
 134         fi
 135         exit $?
 136 fi
 137
 138 if [ -n "$1" ]; then
 139         IFACE="$1"
 140         shift
 141 fi
 142
 143 # -l lists our resolv files, optionally for a specific interface
 144 if [ "x${CMD}" = "x-l" -o "x${CMD}" = "x-i" ]; then
 145         [ -d "${IFACEDIR}" ] || exit 0
 146
 147         # If we have an interface ordering list, then use that.
 148         # It works by just using pathname expansion in the interface directory.
 149         if [ -n "${IFACE}" ]; then
 150                 LIST="${IFACE} $@"
 151         elif [ -r "${RESOLVCONF}"/interface-order ]; then
 152                 LIST="$(cat "${RESOLVCONF}"/interface-order)"
 153         fi
 154
 155         # If we don't have a list then prefer lo, tunnels, ppp
 156         # and then anything else.
 157         if [ -z "${LIST}" ]; then
 158                 LIST="lo lo[0-9]* tap[0-9]* tun[0-9]* vpn vpn[0-9]* ppp[0-9]* ippp[0-9]* *"
 159         fi
 160
 161         cd "${IFACEDIR}"
 162         for IFACE in $(uniqify ${LIST}); do
 163                 # Only list interfaces which we really have
 164                 [ -e "${IFACE}" ] || continue
 165
 166                 if [ "x${CMD}" = "x-i" ]; then
 167                         printf "${IFACE} "
 168                 else
 169                         echo_resolv "${IFACE}"
 170                 fi
 171         done
 172         [ "x${CMD}" = "x-i" ] && echo
 173         exit 0
 174 fi
 175
 176 if [ "x${CMD}" = "x-v" ]; then
 177         NS=
 178         DOMAIN=
 179         SEARCH=
 180         NEWSEARCH=
 181         NEWNS=
 182         NEWDOMAIN=
 183         LINES="$("${argv0}" -l "${IFACE}" | sed -e "s/'/'\\\\''/g" -e "s/^/'/g" -e "s/$/'/g")"
 184         eval set -- ${LINES}
 185         for LINE in "$@"; do
 186                 case "${LINE}" in
 187                         "nameserver "*)
 188                                 case "${LINE#* }" in
 189                                         127.*) continue;;
 190                                 esac
 191                                 NS="${NS}${LINE#* } "
 192                                 ;;
 193                         "domain "*)
 194                                 [ -z "${SEARCH}" ] && DOMAIN="${LINE#* }"
 195                                 ;;
 196                         "search "*)
 197                                 SEARCH="${LINE#* }"
 198                                 DOMAIN=
 199                                 ;;
 200                         *)
 201                                 if [ -z "${LINE}" ]; then
 202                                         for N in ${NS}; do
 203                                                 if [ -n "${DOMAIN}" ]; then
 204                                                         NEWDOMAIN="${NEWDOMAIN} ${DOMAIN},${N}"
 205                                                 elif [ -n "${SEARCH}" ]; then
 206                                                         for S in ${SEARCH}; do
 207                                                                 NEWSEARCH="${NEWSEARCH} ${S},${N}"
 208                                                         done
 209                                                 else
 210                                                         NEWNS="${NEWNS} ${N}"
 211                                                 fi
 212                                         done
 213                                         NS=
 214                                         DOMAIN=
 215                                         SEARCH=
 216                                 fi
 217                                 ;;
 218                 esac
 219         done
 220
 221         # Prefer DOMAIN nameservers over SEARCH nameservers
 222         # if we are supplied both.
 223         NEWDOMAIN="$(uniqify ${NEWDOMAIN})"
 224         NEWSEARCH="$(uniqify ${NEWSEARCH})"
 225         NEWNS="$(uniqify ${NEWNS})"
 226         for S in ${NEWSEARCH}; do
 227                 for DN in ${NEWDOMAIN}; do
 228                         if [ "${S%,*}" = "${DN%,*}" ]; then
 229                                 NEWSEARCH="$(echo "${NEWSEARCH}" | sed -e "s/${S}/${DN}/g")"
 230                                 NEWDOMAIN="$(echo "${NEWDOMAIN}" | sed -e "s/${DN}//g")"
 231                                 break
 232                         fi
 233                 done
 234         done
 235
 236         echo "NEWDOMAIN='${NEWDOMAIN}'"
 237         echo "NEWSEARCH='${NEWSEARCH}'"
 238         echo "NEWNS='${NEWNS}'"
 239         exit 0
 240 fi
 241
 242 # Test that we have valid options
 243 if [ "x${CMD}" = "x-a" -o "x${CMD}" = "x-d" ]; then
 244         if [ -z "${IFACE}" ]; then
 245                 usage "Interface not specified"
 246         fi
 247 elif [ "x${CMD}" != "x-u" ]; then
 248         [ -n "x${CMD}" -a "x${CMD}" != "x-h" ] && usage "Unknown option ${CMD}"
 249         usage
 250 fi
 251 if [ "x${CMD}" = "x-a" ]; then
 252         for x in '/' \\ ' ' '*'; do
 253                 case "${IFACE}" in
 254                         *[${x}]*) error_exit "${x} not allowed in interface name";;
 255                 esac
 256         done
 257         for x in '.' '-' '~'; do
 258                 case "${IFACE}" in
 259                         [${x}]*) error_exit "${x} not allowed at start of interface name";;
 260                 esac
 261         done
 262         [ "x${CMD}" = "x-a" -a -t 0 ] && error_exit "No file given via stdin"
 263         IFACERESOLV="${IFACEDIR}/${IFACE}"
 264 fi
 265
 266 # Ensure that libdir exists
 267 if [ ! -d "${IFACEDIR}" ]; then
 268         if [ ! -d "${VARDIR}" ]; then
 269                 if [ -L "${VARDIR}" ]; then
 270                         DIR="$(readlink "${VARDIR}")"
 271                         # Change to /etc as link maybe relative
 272                         cd "${VARDIR%/*}"
 273                         if ! mkdir -m 0755 -p "${DIR}"; then
 274                                 error_exit "Failed to create needed directory ${DIR}"
 275                         fi
 276                 else
 277                         if ! mkdir -m 0755 -p "${VARDIR}"; then
 278                                 error_exit "Failed to create needed directory ${VARDIR}"
 279                         fi
 280                 fi
 281         fi
 282         mkdir -m 0755 -p "${IFACEDIR}" || \
 283                 error_exit "Failed to create needed directory ${IFACEDIR}"
 284 else
 285         # Delete any existing information about the interface
 286         if [ "x${CMD}" = "x-a" -o "x${CMD}" = "x-d" ]; then
 287                 cd "${IFACEDIR}"
 288                 for iface in ${IFACE}; do
 289                         rm -f "${iface}" || exit $?
 290                 done
 291         fi
 292 fi
 293
 294 if [ "x${CMD}" = "x-a" ]; then
 295         # Create our resolv.conf file
 296         cat >"${IFACEDIR}"/"${IFACE}" || exit $?
 297 fi
 298
 299 retval=0
 300 for x in "${UPDATED}"/*; do
 301         if [ -e "${x}" ]; then
 302                 "${x}" "${CMD}" "${IFACE}"
 303                 retval=$((${retval} + $?))
 304         fi
 305 done
 306
 307 exit ${retval}
 308
 309 # vim: set ts=4 :