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

   1 #!/bin/sh
   2 # Copyright 2006 Gentoo Foundation
   3 # Copyright 2007 Roy Marples
   4 # All rights reserved
   5
   6 # Redistribution and use in source and binary forms, with or without
   7 # modification, are permitted provided that the following conditions
   8 # are met:
   9 #     * Redistributions of source code must retain the above copyright
  10 #       notice, this list of conditions and the following disclaimer.
  11 #     * Redistributions in binary form must reproduce the above
  12 #       copyright notice, this list of conditions and the following
  13 #       disclaimer in the documentation and/or other materials provided
  14 #       with the distribution.
  15 #
  16 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17 # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18 # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19 # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20 # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27
  28 argv0="$0"
  29
  30 PREFIX=
  31 RESOLVCONF="${PREFIX}"/etc/resolvconf
  32 UPDATED="${RESOLVCONF}"/update.d
  33 VARDIR="${RESOLVCONF}"/run
  34 IFACEDIR="${VARDIR}/interfaces"
  35
  36 error_exit() {
  37         echo "$*" >&2
  38         exit 1
  39 }
  40
  41 usage() {
  42         cat <<-EOF
  43         Usage: ${argv0##*/} [options]
  44
  45         Inform the system about any DNS updates.
  46
  47         Options:
  48           -a \$INTERFACE    Add DNS information to the specified interface
  49                            (DNS supplied via stdin in resolv.conf format)
  50           -d \$INTERFACE    Delete DNS information from the specified interface
  51           -u               Run updates from our current DNS information
  52           -l [\$PATTERN]    Show DNS information, optionally from interfaces
  53                            that match the specified pattern
  54           -i [\$PATTERN]    Show interfaces that have supplied DNS information
  55                    optionally from interfaces that match the specified
  56                    pattern
  57           -v [\$PATTERN]    echo NEWDOMAIN, NEWSEARCH and NEWNS variables to
  58                            the console
  59           -h               Show this help cruft
  60         EOF
  61         [ -z "$@" ] && 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 $1"
  69         grep "." "${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 if [ -n "$1" ]; then
  90         IFACE="$1"
  91         shift
  92 fi
  93
  94 # -l is a Gentoo option that lists our resolv files
  95 # optionally for a specific interface
  96 if [ "x${CMD}" = "x-l" -o "x${CMD}" = "x-i" ]; then
  97         [ -d "${IFACEDIR}" ] || exit 0
  98
  99         # If we have an interface ordering list, then use that.
 100         # It works by just using pathname expansion in the interface directory.
 101         if [ -n "${IFACE}" ]; then
 102                 LIST="${IFACE} $@"
 103         elif [ -r "${RESOLVCONF}"/interface-order ]; then
 104                 LIST="$(cat "${RESOLVCONF}"/interface-order)"
 105         fi
 106
 107         # If we don't have a list then prefer lo, tunnels, ppp
 108         # and then anything else.
 109         if [ -z "${LIST}" ]; then
 110                 LIST="lo lo[0-9]* tap[0-9]* tun[0-9]* vpn vpn[0-9]* ppp[0-9]* ippp[0-9]* *"
 111         fi
 112
 113         cd "${IFACEDIR}"
 114         for IFACE in $(uniqify ${LIST}); do
 115                 # Only list interfaces which we really have
 116                 [ -e "${IFACE}" ] || continue
 117
 118                 if [ "x${CMD}" = "x-i" ]; then
 119                         printf "${IFACE} "
 120                 else
 121                         echo_resolv "${IFACE}"
 122                 fi
 123         done
 124         [ "x${CMD}" = "x-i" ] && echo
 125         exit 0
 126 fi
 127
 128 if [ "x${CMD}" = "x-v" ]; then
 129         NS=
 130         DOMAIN=
 131         SEARCH=
 132         NEWSEARCH=
 133         NEWNS=
 134         NEWDOMAIN=
 135         LINES="$("${argv0}" -l "${IFACE}" | sed -e "s/'/'\\\\''/g" -e "s/^/'/g" -e "s/$/'/g")"
 136         eval set -- ${LINES}
 137         for LINE in "$@"; do
 138                 case "${LINE}" in
 139                         "nameserver "*)
 140                                 case "${LINE#* }" in
 141                                         127.*) continue ;;
 142                                 esac
 143                                 NS="${NS}${LINE#* } "
 144                                 ;;
 145                         "domain "*)
 146                                 [ -z "${SEARCH}" ] && DOMAIN="${LINE#* }"
 147                                 ;;
 148                         "search "*)
 149                                 SEARCH="${LINE#* }"
 150                                 DOMAIN=
 151                                 ;;
 152                         *)
 153                                 if [ -z "${LINE}" ]; then
 154                                         for N in ${NS}; do
 155                                                 if [ -n "${DOMAIN}" ]; then
 156                                                         NEWDOMAIN="${NEWDOMAIN} ${DOMAIN},${N}"
 157                                                 elif [ -n "${SEARCH}" ]; then
 158                                                         for S in ${SEARCH}; do
 159                                                                 NEWSEARCH="${NEWSEARCH} ${S},${N}"
 160                                                         done
 161                                                 else
 162                                                         NEWNS="${NEWNS} ${N}"
 163                                                 fi
 164                                         done
 165                                         NS=
 166                                         DOMAIN=
 167                                         SEARCH=
 168                                 fi
 169                                 ;;
 170                 esac
 171         done
 172
 173         # Prefer DOMAIN nameservers over SEARCH nameservers
 174         # if we are supplied both.
 175         NEWDOMAIN="$(uniqify ${NEWDOMAIN})"
 176         NEWSEARCH="$(uniqify ${NEWSEARCH})"
 177         NEWNS="$(uniqify ${NEWNS})"
 178         for S in ${NEWSEARCH}; do
 179                 for DN in ${NEWDOMAIN}; do
 180                         if [ "${S%,*}" = "${DN%,*}" ]; then
 181                                 NEWSEARCH="$(echo "${NEWSEARCH}" | sed -e "s/${S}/${DN}/g")"
 182                                 NEWDOMAIN="$(echo "${NEWDOMAIN}" | sed -e "s/${DN}//g")"
 183                                 break
 184                         fi
 185                 done
 186         done
 187
 188         echo "NEWDOMAIN='${NEWDOMAIN}'"
 189         echo "NEWSEARCH='${NEWSEARCH}'"
 190         echo "NEWNS='${NEWNS}'"
 191         exit 0
 192 fi
 193
 194 # Test that we have valid options
 195 if [ "x${CMD}" = "x-a" -o "x${CMD}" = "x-d" ]; then
 196         if [ -z "${IFACE}" ]; then
 197                 usage "Interface not specified"
 198         fi
 199 elif [ "x${CMD}" != "x-u" ]; then
 200         [ -n "x${CMD}" -a "x${CMD}" != "x-h" ] && usage "Unknown option ${CMD}"
 201         usage
 202 fi
 203 if [ "x${CMD}" = "x-a" ]; then
 204         for x in '/' \\ ' ' '*'; do
 205                 case "${IFACE}" in
 206                         *[${x}]*) error_exit "${x} not allowed in interface name" ;;
 207                 esac
 208         done
 209         for x in '.' '-' '~'; do
 210                 case "${IFACE}" in
 211                         [${x}]*) error_exit "${x} not allowed at start of interface name" ;;
 212                 esac
 213         done
 214         [ "x${CMD}" = "x-a" -a -t 0 ] && error_exit "No file given via stdin"
 215         IFACERESOLV="${IFACEDIR}/${IFACE}"
 216 fi
 217
 218 # Ensure that libdir exists
 219 if [ ! -d "${IFACEDIR}" ]; then
 220         if [ ! -d "${VARDIR}" ]; then
 221                 if [ -L "${VARDIR}" ]; then
 222                         DIR="$(readlink "${VARDIR}")"
 223                         # Change to /etc as link maybe relative
 224                         cd "${VARDIR%/*}"
 225                         if ! mkdir -m 0755 -p "${DIR}"; then
 226                                 error_exit "Failed to create needed directory ${DIR}"
 227                         fi
 228                 else
 229                         if ! mkdir -m 0755 -p "${VARDIR}"; then
 230                                 error_exit "Failed to create needed directory ${VARDIR}"
 231                         fi
 232                 fi
 233         fi
 234         mkdir -m 0755 -p "${IFACEDIR}" || \
 235                 error_exit "Failed to create needed directory ${IFACEDIR}"
 236 else
 237         # Delete any existing information about the interface
 238         if [ "x${CMD}" = "x-a" -o "x${CMD}" = "x-d" ]; then
 239                 cd "${IFACEDIR}"
 240                 for iface in ${IFACE}; do
 241                         rm -f "${iface}" || exit $?
 242                 done
 243         fi
 244 fi
 245
 246 if [ "x${CMD}" = "x-a" ]; then
 247         # Create our resolv.conf file
 248         cat >"${IFACEDIR}"/"${IFACE}" || exit $?
 249 fi
 250
 251 retval=0
 252 for x in "${UPDATED}"/*; do
 253         if [ -e "${x}" ]; then
 254                 "${x}" "${CMD}" "${IFACE}"
 255                 retval=$((${retval} + $?))
 256         fi
 257 done
 258
 259 exit ${retval}
 260
 261 # vim: set ts=4 :