/contrib/openresolv/libc.in

  1#!/bin/sh
  2# Copyright (c) 2007-2009 Roy Marples
  3# All rights reserved
  4
  5# libc subscriber for resolvconf
  6
  7# Redistribution and use in source and binary forms, with or without
  8# modification, are permitted provided that the following conditions
  9# are met:
 10#     * Redistributions of source code must retain the above copyright
 11#       notice, this list of conditions and the following disclaimer.
 12#     * Redistributions in binary form must reproduce the above
 13#       copyright notice, this list of conditions and the following
 14#       disclaimer in the documentation and/or other materials provided
 15#       with the distribution.
 16#
 17# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 18# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 19# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 20# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 21# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 22# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 23# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 24# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 25# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 26# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 27# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 28
 29SYSCONFDIR=@SYSCONFDIR@
 30LIBEXECDIR=@LIBEXECDIR@
 31VARDIR=@VARDIR@
 32IFACEDIR="$VARDIR/interfaces"
 33NL="
 34"
 35
 36# sed may not be available, and this is faster on small files
 37key_get_value()
 38{
 39	local key="$1" value= x= line=
 40
 41	shift
 42	if [ $# -eq 0 ]; then
 43		while read line; do
 44			case "$line" in
 45			"$key"*) echo "${line##$key}";;
 46			esac
 47		done
 48	else
 49		for x; do
 50			while read line; do
 51				case "$line" in
 52				"$key"*) echo "${line##$key}";;
 53				esac
 54			done < "$x"
 55		done
 56	fi
 57}
 58
 59# Support original resolvconf configuration layout
 60# as well as the openresolv config file
 61if [ -f "$SYSCONFDIR"/resolvconf.conf ]; then
 62	. "$SYSCONFDIR"/resolvconf.conf
 63elif [ -d "$SYSCONFDIR"/resolvconf ]; then
 64	SYSCONFDIR="$SYSCONFDIR/resolvconf/resolv.conf.d"
 65	base="$SYSCONFDIR/resolv.conf.d/base"
 66	if [ -f "$base" ]; then
 67		name_servers="$(key_get_value "nameserver " "$base")"
 68		search_domains="$(key_get_value "search " "$base")"
 69		if [ -z "$search_domains" ]; then
 70			search_domains="$(key_get_value "domain " "$base")"
 71		fi
 72		resolv_conf_options="$(key_get_value "options " "$base")"
 73	fi
 74	if [ -f "$SYSCONFDIR"/resolv.conf.d/head ]; then
 75		resolv_conf_head="$(cat "${SYSCONFDIR}"/resolv.conf.d/head)"
 76	fi
 77	if [ -f "$SYSCONFDIR"/resolv.conf.d/tail ]; then
 78		resolv_conf_tail="$(cat "$SYSCONFDIR"/resolv.conf.d/tail)"
 79	fi
 80fi
 81: ${resolv_conf:=/etc/resolv.conf}
 82: ${libc_service:=nscd}
 83: ${libc_restart:=@RESTARTCMD ${libc_service}@}
 84: ${list_resolv:=@PREFIX@/sbin/resolvconf -l}
 85if [ "${resolv_conf_head-x}" = x -a -f "$SYSCONFDIR"/resolv.conf.head ]; then
 86	resolv_conf_head="$(cat "${SYSCONFDIR}"/resolv.conf.head)"
 87fi
 88if [ "${resolv_conf_tail-x}" = x -a -f "$SYSCONFDIR"/resolv.conf.tail ]; then
 89	resolv_conf_tail="$(cat "$SYSCONFDIR"/resolv.conf.tail)"
 90fi
 91
 92uniqify()
 93{
 94	local result=
 95	while [ -n "$1" ]; do
 96		case " $result " in
 97		*" $1 "*);;
 98		*) result="$result $1";;
 99		esac
100		shift
101	done
102	echo "${result# *}"
103}
104
105case "${resolv_conf_passthrough:-NO}" in
106[Yy][Ee][Ss]|[Tt][Rr][Uu][Ee]|[Oo][Nn]|1)
107	newest=
108	for conf in "$IFACEDIR"/*; do
109		if [ -z "$newest" -o "$conf" -nt "$newest" ]; then
110			newest="$conf"
111		fi
112	done
113	[ -z "$newest" ] && exit 0
114	newconf="$(cat "$newest")$NL"
115	;;
116*)
117	[ -z "$RESOLVCONF" ] && eval "$(@PREFIX@/sbin/resolvconf -v)"
118	newsearch="$(uniqify $search_domains $SEARCH $search_domains_append)"
119	NS="$LOCALNAMESERVERS $NAMESERVERS"
120	newns="$(uniqify $name_servers $NS $name_servers_append)"
121
122	# Hold our new resolv.conf in a variable to save on temporary files
123	newconf="# Generated by resolvconf$NL"
124	if [ -n "$resolv_conf_head" ]; then
125		newconf="$newconf$resolv_conf_head$NL"
126	fi
127	[ -n "$newsearch" ] && newconf="${newconf}search $newsearch$NL"
128	for n in $newns; do
129		newconf="${newconf}nameserver $n$NL"
130	done
131
132	# Now get any configured options
133	opts="$resolv_conf_options${resolv_conf_options:+ }"
134	opts="$opts$($list_resolv | key_get_value "options ")"
135	if [ -n "$opts" ]; then
136		newconf="${newconf}options"
137		for opt in $(uniqify $opts); do
138			newconf="${newconf} $opt"
139		done
140		newconf="$newconf$NL"
141	fi
142
143	if [ -n "$resolv_conf_tail" ]; then
144		newconf="$newconf$resolv_conf_tail$NL"
145	fi
146	;;
147esac
148
149# Check if the file has actually changed or not
150if [ -e "$resolv_conf" ]; then
151	[ "$(cat "$resolv_conf")" = "$(printf %s "$newconf")" ] && exit 0
152fi
153
154# Create our resolv.conf now
155(umask 022; echo "$newconf" >"$resolv_conf")
156eval $libc_restart
157
158retval=0
159# Notify users of the resolver
160for script in "$LIBEXECDIR"/libc.d/*; do
161	if [ -f "$script" ]; then
162		if [ -x "$script" ]; then
163			"$script" "$@"
164		else
165			(. "$script" "$@")
166		fi
167		retval=$(($retval + $?))
168	fi
169done
170exit $retval