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

   1 #!/bin/sh
   2 # Copyright 2007-2008 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: ${argv0##*/} [options]
  43
  44         Inform the system about any DNS updates.
  45
  46         Options:
  47           -a \$INTERFACE    Add DNS information to the specified interface
  48                            (DNS supplied via stdin in resolv.conf format)
  49           -d \$INTERFACE    Delete DNS information from the specified interface
  50           -f               Ignore non existant interfaces
  51           -u               Run updates from our current DNS information
  52           -l [\$PATTERN]    Show DNS information, optionally from interfaces
  53                            that match the specified pattern
  54           -i [\$PATTERN]    Show interfaces that have supplied DNS information
  55                    optionally from interfaces that match the specified
  56                    pattern
  57           -v [\$PATTERN]    echo NEWDOMAIN, NEWSEARCH and NEWNS variables to
  58                            the console
  59           -s \$SVC \$CMD     Do \$CMD for the system service \$SVC
  60           -h               Show this help cruft
  61         EOF
  62         [ -z "$@" ] && exit 0
  63         echo
  64         error_exit "$*"
  65 }
  66
  67 echo_resolv() {
  68         [ -n "$1" -a -e "${IFACEDIR}/$1" ] || return 1
  69         echo "# resolv.conf for interface $1"
  70         cat "${IFACEDIR}/$1"
  71         echo
  72 }
  73
  74 uniqify() {
  75     local result=
  76     while [ -n "$1" ]; do
  77                 case " ${result} " in
  78                         *" $1 "*);;
  79                         *) result="${result} $1";;
  80                 esac
  81                 shift
  82         done
  83     echo "${result# *}"
  84 }
  85
  86 FORCE=false
  87 while getopts a:d:fhils:uv OPT; do
  88         case "${OPT}" in
  89                 f) FORCE=true;;
  90                 h) usage;;
  91                 s) CMD=s; SERVICE="${OPTARG}";;
  92                 '?') exit 1;;
  93                 *) CMD="${OPT}"; IFACE="${OPTARG}";;
  94         esac
  95 done
  96 shift $((${OPTIND} - 1))
  97 ARGS="${IFACE}${IFACE:+ }$@"
  98
  99 # We do our service restarting here so that our subscribers don't have to know
 100 # about the OS's init system.
 101 if [ "${CMD}" = "s" ]; then
 102         if [ -n "$1" ]; then
 103                 ACTION="$1"
 104                 shift
 105         fi
 106         [ -z "${ACTION}" ] && usage "Action not specified"
 107
 108         # If restarting check if service is running or not if we can
 109         if [ "${ACTION}" = "restart" ]; then
 110                 if [ -s /var/run/"${SERVICE}".pid ]; then
 111                         kill -0 $(cat /var/run/"${SERVICE}".pid) 2>/dev/null
 112                 elif [ -s /var/run/"${SERVICE}"/"${SERVICE}".pid ]; then
 113                         kill -0 $(cat /var/run/"${SERVICE}".pid) 2>/dev/null
 114                 elif [ -s /var/run/"${SERVICE}"/pid ]; then
 115                         kill -0 $(cat /var/run/"${SERVICE}"/pid) 2>/dev/null
 116                 else
 117                         false
 118                 fi
 119                 # Service not running, so don't restart
 120                 [ $? != 0 ] && exit 0
 121         fi
 122         if [ -x /sbin/service ]; then
 123                 service "${SERVICE}" "${ACTION}" "$@"
 124         elif [ -x /etc/init.d/"${SERVICE}" -a -x /sbin/runscript ]; then
 125                 if [ "${ACTION}" = "restart" ]; then
 126                         /etc/init.d/"${SERVICE}" --quiet --nodeps conditionalrestart "$@"
 127                 else
 128                         /etc/init.d/"${SERVICE}" --quiet --nodeps "${ACTION}" "$@"
 129                 fi
 130         elif [ -x /etc/init.d/"${SERVICE}" ]; then
 131                 /etc/init.d/"${SERVICE}" "${ACTION}" "$@"
 132         elif [ -x /etc/rc.d/"${SERVICE}" ]; then
 133                 /etc/rc.d/"${SERVICE}" "${ACTION}" "$@"
 134         elif [ -x /etc/rc.d/rc."${SERVICE}" ]; then
 135                 /etc/rc.d/rc."${SERVICE}" "${ACTION}" "$@"
 136         else
 137                 error_exit "Don't know how to interact with services on this platform"
 138         fi
 139         exit $?
 140 fi
 141
 142 # -l lists our resolv files, optionally for a specific interface
 143 if [ "${CMD}" = "l" -o "${CMD}" = "i" ]; then
 144         [ -d "${IFACEDIR}" ] || exit 0
 145
 146         REPORT=false
 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 "${ARGS}" ]; then
 150                 LIST="${ARGS}"
 151                 ${FORCE} || REPORT=true
 152         elif [ -r "${RESOLVCONF}"/interface-order ]; then
 153                 LIST="$(cat "${RESOLVCONF}"/interface-order)"
 154         fi
 155
 156         # If we don't have a list then prefer lo, tunnels, ppp
 157         # and then anything else.
 158         if [ -z "${LIST}" ]; then
 159                 LIST="lo lo[0-9]* tap[0-9]* tun[0-9]* vpn vpn[0-9]* ppp[0-9]* ippp[0-9]* *"
 160         fi
 161
 162         RETVAL=0
 163         cd "${IFACEDIR}"
 164         for IFACE in $(uniqify ${LIST}); do
 165                 # Only list interfaces which we really have
 166                 if ! [ -e "${IFACE}" ]; then
 167                         if ${REPORT}; then
 168                                 echo "No resolv.conf for interface ${IFACE}" >&2
 169                                 RETVAL=$((${RETVAL} + 1))
 170                         fi
 171                         continue
 172                 fi
 173
 174                 if [ "${CMD}" = "i" ]; then
 175                         printf "${IFACE} "
 176                 else
 177                         echo_resolv "${IFACE}"
 178                 fi
 179         done
 180         [ "${CMD}" = "i" ] && echo
 181         exit ${RETVAL}
 182 fi
 183
 184 if [ "${CMD}" = "v" ]; then
 185         NS=
 186         DOMAIN=
 187         SEARCH=
 188         NEWSEARCH=
 189         NEWNS=
 190         NEWDOMAIN=
 191         LINES="$("${argv0}" -l "${IFACE}" |
 192                 sed -e "s/'/'\\\\''/g" -e "s/^/'/g" -e "s/$/'/g")"
 193         eval set -- ${LINES}
 194         for LINE in "$@"; do
 195                 case "${LINE}" in
 196                         "nameserver "*)
 197                                 case "${LINE#* }" in
 198                                         127.*) continue;;
 199                                 esac
 200                                 NS="${NS}${LINE#* } "
 201                                 ;;
 202                         "domain "*)
 203                                 [ -z "${SEARCH}" ] && DOMAIN="${LINE#* }"
 204                                 ;;
 205                         "search "*)
 206                                 SEARCH="${LINE#* }"
 207                                 DOMAIN=
 208                                 ;;
 209                         *)
 210                                 if [ -z "${LINE}" ]; then
 211                                         for N in ${NS}; do
 212                                                 if [ -n "${DOMAIN}" ]; then
 213                                                         NEWDOMAIN="${NEWDOMAIN} ${DOMAIN},${N}"
 214                                                 elif [ -n "${SEARCH}" ]; then
 215                                                         for S in ${SEARCH}; do
 216                                                                 NEWSEARCH="${NEWSEARCH} ${S},${N}"
 217                                                         done
 218                                                 else
 219                                                         NEWNS="${NEWNS} ${N}"
 220                                                 fi
 221                                         done
 222                                         NS=
 223                                         DOMAIN=
 224                                         SEARCH=
 225                                 fi
 226                                 ;;
 227                 esac
 228         done
 229
 230         # Prefer DOMAIN nameservers over SEARCH nameservers
 231         # if we are supplied both.
 232         NEWDOMAIN="$(uniqify ${NEWDOMAIN})"
 233         NEWSEARCH="$(uniqify ${NEWSEARCH})"
 234         NEWNS="$(uniqify ${NEWNS})"
 235         for S in ${NEWSEARCH}; do
 236                 for DN in ${NEWDOMAIN}; do
 237                         if [ "${S%,*}" = "${DN%,*}" ]; then
 238                                 NEWSEARCH="$(echo "${NEWSEARCH}" |
 239                                         sed -e "s/${S}/${DN}/g")"
 240                                 NEWDOMAIN="$(echo "${NEWDOMAIN}" |
 241                                         sed -e "s/${DN}//g")"
 242                                 break
 243                         fi
 244                 done
 245         done
 246
 247         echo "NEWDOMAIN='${NEWDOMAIN}'"
 248         echo "NEWSEARCH='${NEWSEARCH}'"
 249         echo "NEWNS='${NEWNS}'"
 250         exit 0
 251 fi
 252
 253 # Test that we have valid options
 254 if [ "${CMD}" = "a" -o "${CMD}" = "d" ]; then
 255         if [ -z "${IFACE}" ]; then
 256                 usage "Interface not specified"
 257         fi
 258 elif [ "${CMD}" != "u" ]; then
 259         [ -n "${CMD}" -a "${CMD}" != "h" ] && usage "Unknown option ${CMD}"
 260         usage
 261 fi
 262 if [ "${CMD}" = "a" ]; then
 263         for x in '/' \\ ' ' '*'; do
 264                 case "${IFACE}" in
 265                         *[${x}]*) error_exit "${x} not allowed in interface name";;
 266                 esac
 267         done
 268         for x in '.' '-' '~'; do
 269                 case "${IFACE}" in
 270                         [${x}]*) error_exit "${x} not allowed at start of interface name";;
 271                 esac
 272         done
 273         [ "${CMD}" = "a" -a -t 0 ] && error_exit "No file given via stdin"
 274         IFACERESOLV="${IFACEDIR}/${IFACE}"
 275 fi
 276
 277 # Ensure that libdir exists
 278 if [ ! -d "${IFACEDIR}" ]; then
 279         if [ ! -d "${VARDIR}" ]; then
 280                 if [ -L "${VARDIR}" ]; then
 281                         DIR="$(readlink "${VARDIR}")"
 282                         # Change to /etc as link maybe relative
 283                         cd "${VARDIR%/*}"
 284                         if ! mkdir -m 0755 -p "${DIR}"; then
 285                                 error_exit "Failed to create needed directory ${DIR}"
 286                         fi
 287                 else
 288                         if ! mkdir -m 0755 -p "${VARDIR}"; then
 289                                 error_exit "Failed to create needed directory ${VARDIR}"
 290                         fi
 291                 fi
 292         fi
 293         mkdir -m 0755 -p "${IFACEDIR}" || \
 294                 error_exit "Failed to create needed directory ${IFACEDIR}"
 295 else
 296         # Delete any existing information about the interface
 297         if [ "${CMD}" = "a" -o "${CMD}" = "d" ]; then
 298                 cd "${IFACEDIR}"
 299                 for iface in ${IFACE}; do
 300                         if [ "${CMD}" = "d" -a ! -e "${iface}" ]; then
 301                                 ${FORCE} && continue
 302                                 error_exit "No resolv.conf for interface ${iface}"
 303                         fi
 304                         rm -f "${iface}" || exit $?
 305                 done
 306         fi
 307 fi
 308
 309 if [ "${CMD}" = "a" ]; then
 310         # Create our resolv.conf file
 311         cat >"${IFACEDIR}"/"${IFACE}" || exit $?
 312 fi
 313
 314 RETVAL=0
 315 for x in "${UPDATED}"/*; do
 316         if [ -e "${x}" ]; then
 317                 "${x}" "${CMD}" "${IFACE}"
 318                 RETVAL=$((${RETVAL} + $?))
 319         fi
 320 done
 321
 322 exit ${RETVAL}