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="$0"
  28 SYSCONFDIR=@SYSCONFDIR@
  29 VARDIR=@VARBASE@/run/resolvconf
  30 IFACEDIR="${VARDIR}/interfaces"
  31 METRICDIR="${VARDIR}/metrics"
  32
  33 error_exit()
  34 {
  35         echo "$*" >&2
  36         exit 1
  37 }
  38
  39 usage()
  40 {
  41         cat <<-EOF
  42         Usage: ${ARGV0##*/} [options]
  43
  44         Inform the system about any DNS updates.
  45
  46         Options:
  47           -a \$INTERFACE    Add DNS information to the specified interface
  48                            (DNS supplied via stdin in resolv.conf format)
  49           -m metric        Give the added DNS information a metric
  50           -d \$INTERFACE    Delete DNS information from the specified interface
  51           -f               Ignore non existant interfaces
  52           -u               Run updates from our current DNS information
  53           -l [\$PATTERN]    Show DNS information, optionally from interfaces
  54                            that match the specified pattern
  55           -i [\$PATTERN]    Show interfaces that have supplied DNS information
  56                    optionally from interfaces that match the specified
  57                    pattern
  58           -v [\$PATTERN]    echo NEWDOMAIN, NEWSEARCH and NEWNS variables to
  59                            the console
  60           -s \$SVC \$CMD     Do \$CMD for the system service \$SVC
  61           -h               Show this help cruft
  62         EOF
  63         [ -z "$@" ] && exit 0
  64         echo
  65         error_exit "$*"
  66 }
  67
  68 echo_resolv()
  69 {
  70         local LINE=
  71         [ -n "$1" -a -e "${IFACEDIR}/$1" ] || return 1
  72         echo "# resolv.conf from $1"
  73         # Our variable maker works of the fact each resolv.conf per interface
  74         # is separated by blank lines.
  75         # So we remove them when echoing them.
  76         while read LINE; do
  77                 [ -n "${LINE}" ] && echo "${LINE}"
  78         done < "${IFACEDIR}/$1"
  79         echo
  80 }
  81
  82 # Parse resolv.conf's and make variables
  83 # for domain name servers, search name servers and global nameservers
  84 parse_resolv()
  85 {
  86         local LINE= NS= DOMAIN= SEARCH= N= NEWDOMAIN= NEWSEARCH= NEWNS=
  87
  88         echo "NEWDOMAIN="
  89         echo "NEWSEARCH="
  90         echo "NEWNS="
  91
  92         while read LINE; do
  93                 case "${LINE}" in
  94                 "nameserver "*)
  95                         case "${LINE#* }" in
  96                         127.*) continue;;
  97                         esac
  98                         NS="${NS}${LINE#* } "
  99                         ;;
 100                 "domain "*)
 101                         [ -z "${SEARCH}" ] && DOMAIN="${LINE#* }"
 102                         ;;
 103                 "search "*)
 104                         SEARCH="${LINE#* }"
 105                         DOMAIN=
 106                         ;;
 107                 *)
 108                         if [ -z "${LINE}" ]; then
 109                                 for N in ${NS}; do
 110                                         if [ -n "${DOMAIN}" ]; then
 111                                                 echo "NEWDOMAIN=\"\${NEWDOMAIN} ${DOMAIN},${N}\""
 112                                         elif [ -n "${SEARCH}" ]; then
 113                                                 for S in ${SEARCH}; do
 114                                                         echo "NEWSEARCH=\"\${NEWSEARCH} ${S},${N}\""
 115                                                 done
 116                                         else
 117                                                 echo "NEWNS=\"\${NEWNS} ${N}\""
 118                                         fi
 119                                 done
 120                                 NS=
 121                                 DOMAIN=
 122                                 SEARCH=
 123                         fi
 124                         ;;
 125                 esac
 126         done
 127 }
 128
 129 uniqify()
 130 {
 131     local result=
 132     while [ -n "$1" ]; do
 133                 case " ${result} " in
 134                 *" $1 "*);;
 135                 *) result="${result} $1";;
 136                 esac
 137                 shift
 138         done
 139     echo "${result# *}"
 140 }
 141
 142 FORCE=false
 143 while getopts a:d:fhilm:s:uv OPT; do
 144         case "${OPT}" in
 145         f) FORCE=true;;
 146         h) usage;;
 147         m) IF_METRIC="${OPTARG}";;
 148         s) CMD=s; SERVICE="${OPTARG}";;
 149         '?') ;;
 150         *) CMD="${OPT}"; IFACE="${OPTARG}";;
 151         esac
 152 done
 153 shift $((${OPTIND} - 1))
 154 ARGS="${IFACE}${IFACE:+ }$@"
 155
 156 # We do our service restarting here so that our subscribers don't have to know
 157 # about the OS's init system.
 158 if [ "${CMD}" = "s" ]; then
 159         if [ -n "$1" ]; then
 160                 ACTION="$1"
 161                 shift
 162         fi
 163         [ -z "${ACTION}" ] && usage "Action not specified"
 164
 165         # If restarting check if service is running or not if we can
 166         if [ "${ACTION}" = "restart" ]; then
 167                 if [ -s /var/run/"${SERVICE}".pid ]; then
 168                         kill -0 $(cat /var/run/"${SERVICE}".pid) 2>/dev/null
 169                 elif [ -s /var/run/"${SERVICE}"/"${SERVICE}".pid ]; then
 170                         kill -0 $(cat /var/run/"${SERVICE}"/"${SERVICE}".pid) 2>/dev/null
 171                 elif [ -s /var/run/"${SERVICE}"/pid ]; then
 172                         kill -0 $(cat /var/run/"${SERVICE}"/pid) 2>/dev/null
 173                 else
 174                         false
 175                 fi
 176                 # Service not running, so don't restart
 177                 [ $? != 0 ] && exit 0
 178         fi
 179         if [ -x /sbin/service ]; then
 180                 service "${SERVICE}" "${ACTION}" "$@"
 181         elif [ -x /etc/init.d/"${SERVICE}" -a -x /sbin/runscript ]; then
 182                 if [ "${ACTION}" = "restart" ]; then
 183                         /etc/init.d/"${SERVICE}" --quiet --nodeps conditionalrestart "$@"
 184                 else
 185                         /etc/init.d/"${SERVICE}" --quiet --nodeps "${ACTION}" "$@"
 186                 fi
 187         elif [ -x /etc/init.d/"${SERVICE}" ]; then
 188                 /etc/init.d/"${SERVICE}" "${ACTION}" "$@"
 189         elif [ -x /etc/rc.d/"${SERVICE}" ]; then
 190                 /etc/rc.d/"${SERVICE}" "${ACTION}" "$@"
 191         elif [ -x /etc/rc.d/rc."${SERVICE}" ]; then
 192                 /etc/rc.d/rc."${SERVICE}" "${ACTION}" "$@"
 193         else
 194                 error_exit "Don't know how to interact with services on this platform"
 195         fi
 196         exit $?
 197 fi
 198
 199 # -l lists our resolv files, optionally for a specific interface
 200 if [ "${CMD}" = "l" -o "${CMD}" = "i" ]; then
 201         [ -d "${IFACEDIR}" ] || exit 0
 202
 203         REPORT=false
 204         # If we have an interface ordering list, then use that.
 205         # It works by just using pathname expansion in the interface directory.
 206         if [ -n "${ARGS}" ]; then
 207                 LIST="${ARGS}"
 208                 ${FORCE} || REPORT=true
 209         elif [ -r "${SYSCONFDIR}"/interface-order ]; then
 210                 LIST="lo lo[0-9]* $(cat "${SYSCONFDIR}"/interface-order) *"
 211         fi
 212         # If we don't have a list then prefer lo, metrics, tunnels, ppp
 213         # and then anything else.
 214         if [ -z "${LIST}" ]; then
 215                 LIST="lo lo[0-9]* "
 216                 cd "${METRICDIR}"
 217                 for METRIC in *; do
 218                         LIST="${LIST} ${METRIC#* }"
 219                 done
 220                 LIST="${LIST} tap[0-9]* tun[0-9]* vpn vpn[0-9]* ppp[0-9]* ippp[0-9]* *"
 221         fi
 222
 223         RETVAL=0
 224         cd "${IFACEDIR}"
 225         for IFACE in $(uniqify ${LIST}); do
 226                 # Only list interfaces which we really have
 227                 if ! [ -e "${IFACE}" ]; then
 228                         if ${REPORT}; then
 229                                 echo "No resolv.conf for interface ${IFACE}" >&2
 230                                 RETVAL=$((${RETVAL} + 1))
 231                         fi
 232                         continue
 233                 fi
 234
 235                 if [ "${CMD}" = "i" ]; then
 236                         printf "${IFACE} "
 237                 else
 238                         echo_resolv "${IFACE}"
 239                 fi
 240         done
 241         [ "${CMD}" = "i" ] && echo
 242         exit ${RETVAL}
 243 fi
 244
 245 if [ "${CMD}" = "v" ]; then
 246         eval "$("${ARGV0}" -l "${IFACE}" | parse_resolv)"
 247
 248         # Prefer DOMAIN nameservers over SEARCH nameservers
 249         # if we are supplied both, but put them in the SEARCH list
 250         NEWDOMAIN="$(uniqify ${NEWDOMAIN})"
 251         NEWSEARCH="$(uniqify ${NEWSEARCH})"
 252         NEWNS="$(uniqify ${NEWNS})"
 253         _NEWDOMAIN=
 254         _NEWSEARCH=
 255         for S in ${NEWSEARCH}; do
 256                 for DN in ${NEWDOMAIN}; do
 257                         if [ "${S%,*}" = "${DN%,*}" ]; then
 258                                 S="${DN}"
 259                                 break
 260                         fi
 261                 done
 262                 _NEWSEARCH="${_NEWSEARCH}${_NEWSEARCH:+ }${S}"
 263         done
 264         for DN in ${NEWDOMAIN}; do
 265                 for S in ${_NEWSEARCH}; do
 266                         if [ "${S%,*}" = "${DN%,*}" ]; then
 267                                 DN=
 268                                 break
 269                         fi
 270                 done
 271                 if [ -n "${DN}" ]; then
 272                         _NEWDOMAIN="${_NEWDOMAIN}${_NEWDOMAIN:+ }${DN}"
 273                 fi
 274         done
 275
 276         echo "NEWDOMAIN='${_NEWDOMAIN}'"
 277         echo "NEWSEARCH='${_NEWSEARCH}'"
 278         echo "NEWNS='${NEWNS}'"
 279         exit 0
 280 fi
 281
 282 # Test that we have valid options
 283 if [ "${CMD}" = "a" -o "${CMD}" = "d" ]; then
 284         if [ -z "${IFACE}" ]; then
 285                 usage "Interface not specified"
 286         fi
 287 elif [ "${CMD}" != "u" ]; then
 288         [ -n "${CMD}" -a "${CMD}" != "h" ] && usage "Unknown option ${CMD}"
 289         usage
 290 fi
 291 if [ "${CMD}" = "a" ]; then
 292         for x in '/' \\ ' ' '*'; do
 293                 case "${IFACE}" in
 294                 *[${x}]*) error_exit "${x} not allowed in interface name";;
 295                 esac
 296         done
 297         for x in '.' '-' '~'; do
 298                 case "${IFACE}" in
 299                 [${x}]*) error_exit "${x} not allowed at start of interface name";;
 300                 esac
 301         done
 302         [ "${CMD}" = "a" -a -t 0 ] && error_exit "No file given via stdin"
 303         IFACERESOLV="${IFACEDIR}/${IFACE}"
 304 fi
 305
 306 # Ensure that libdir exists
 307 if [ ! -d "${IFACEDIR}" ]; then
 308         if [ ! -d "${VARDIR}" ]; then
 309                 if [ -L "${VARDIR}" ]; then
 310                         DIR="$(readlink "${VARDIR}")"
 311                         # Change to /etc as link maybe relative
 312                         cd "${VARDIR%/*}"
 313                         if ! mkdir -m 0755 -p "${DIR}"; then
 314                                 error_exit "Failed to create needed directory ${DIR}"
 315                         fi
 316                 else
 317                         if ! mkdir -m 0755 -p "${VARDIR}"; then
 318                                 error_exit "Failed to create needed directory ${VARDIR}"
 319                         fi
 320                 fi
 321         fi
 322         mkdir -m 0755 -p "${IFACEDIR}" || \
 323                 error_exit "Failed to create needed directory ${IFACEDIR}"
 324 else
 325         # Delete any existing information about the interface
 326         if [ "${CMD}" = "d" ]; then
 327                 cd "${IFACEDIR}"
 328                 for ARG in ${ARGS}; do
 329                         if [ "${CMD}" = "d" -a ! -e "${ARG}" ]; then
 330                                 ${FORCE} && continue
 331                                 error_exit "No resolv.conf for interface ${ARG}"
 332                         fi
 333                         rm -f "${ARG}" "${METRICDIR}/"*" ${ARG}" || exit $?
 334                 done
 335         fi
 336 fi
 337
 338 if [ "${CMD}" = "a" ]; then
 339         # Read resolv.conf from stdin
 340         RESOLV="$(cat)\n"
 341         # If what we are given matches what we have, then do nothing
 342         if [ -e "${IFACEDIR}/${IFACE}" ]; then
 343                 if [ "$(printf "${RESOLV}")" = "$(cat "${IFACEDIR}/${IFACE}")" ]
 344                 then
 345                         exit 0
 346                 fi
 347                 rm "${IFACEDIR}/${IFACE}"
 348         fi
 349         printf "${RESOLV}" >"${IFACEDIR}/${IFACE}" || exit $?
 350         rm -f "${METRICDIR}/"*" ${IFACE}"
 351         if [ ! -d "${METRICDIR}" ]; then
 352                 mkdir "${METRICDIR}"
 353         fi
 354         rm -f "${METRICDIR}/"*" ${IFACE}"
 355         # Pad metric to 6 characters, so 5 is less than 10
 356         # All interfaces will get a default metric of 0
 357         while [ ${#IF_METRIC} -le 6 ]; do
 358                 IF_METRIC="0${IF_METRIC}"
 359         done
 360         echo " " >"${METRICDIR}/${IF_METRIC} ${IFACE}"
 361 fi
 362
 363 RETVAL=0
 364 for SCRIPT in "${SYSCONFDIR}"/update.d/*; do
 365         if [ -e "${SCRIPT}" ]; then
 366                 "${SCRIPT}" "${CMD}" "${IFACE}"
 367                 RETVAL=$((${RETVAL} + $?))
 368         fi
 369 done
 370
 371 exit ${RETVAL}