dhclient-script revision 154760
1#!/bin/sh 2# 3# $OpenBSD: dhclient-script,v 1.6 2004/05/06 18:22:41 claudio Exp $ 4# $FreeBSD: head/sbin/dhclient/dhclient-script 154760 2006-01-24 06:11:55Z brooks $ 5# 6# Copyright (c) 2003 Kenneth R Westerback <krw@openbsd.org> 7# 8# Permission to use, copy, modify, and distribute this software for any 9# purpose with or without fee is hereby granted, provided that the above 10# copyright notice and this permission notice appear in all copies. 11# 12# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 13# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 14# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 15# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 16# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 17# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 18# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 19# 20# 21 22ARP=/usr/sbin/arp 23AWK=/usr/bin/awk 24HOSTNAME=/bin/hostname 25NETSTAT=/usr/bin/netstat 26 27LOCALHOST=127.0.0.1 28 29if [ -x /usr/bin/logger ]; then 30 LOGGER="/usr/bin/logger -s -p user.notice -t dhclient" 31else 32 LOGGER=echo 33fi 34 35# 36# Helper functions that implement common actions. 37# 38 39check_hostname() { 40 current_hostname=`$HOSTNAME` 41 if [ -z "$current_hostname" ]; then 42 $LOGGER "New Hostname ($interface): $new_host_name" 43 $HOSTNAME $new_host_name 44 elif [ "$current_hostname" = "$old_host_name" -a \ 45 "$new_host_name" != "$old_host_name" ]; then 46 $LOGGER "New Hostname ($interface): $new_host_name" 47 $HOSTNAME $new_host_name 48 fi 49} 50 51arp_flush() { 52 arp -an -i $interface | \ 53 sed -n -e 's/^.*(\(.*\)) at .*$/arp -d \1/p' | \ 54 sh >/dev/null 2>&1 55} 56 57delete_old_address() { 58 eval "ifconfig $interface inet -alias $old_ip_address $medium" 59} 60 61add_new_address() { 62 eval "ifconfig $interface \ 63 inet $new_ip_address \ 64 netmask $new_subnet_mask \ 65 broadcast $new_broadcast_address \ 66 $medium" 67 68 $LOGGER "New IP Address ($interface): $new_ip_address" 69 $LOGGER "New Subnet Mask ($interface): $new_subnet_mask" 70 $LOGGER "New Broadcast Address ($interface): $new_broadcast_address" 71 $LOGGER "New Routers ($interface): $new_routers" 72} 73 74delete_old_alias() { 75 if [ -n "$alias_ip_address" ]; then 76 ifconfig $interface inet -alias $alias_ip_address > /dev/null 2>&1 77 #route delete $alias_ip_address $LOCALHOST > /dev/null 2>&1 78 fi 79} 80 81add_new_alias() { 82 if [ -n "$alias_ip_address" ]; then 83 ifconfig $interface inet alias $alias_ip_address netmask \ 84 $alias_subnet_mask 85 #route add $alias_ip_address $LOCALHOST 86 fi 87} 88 89delete_old_routes() { 90 #route delete "$old_ip_address" $LOCALHOST >/dev/null 2>&1 91 for router in $old_routers; do 92 if [ $if_defaultroute = x -o $if_defaultroute = $interface ]; then 93 route delete default $route >/dev/null 2>&1 94 fi 95 done 96 97 if [ -n "$old_static_routes" ]; then 98 set $old_static_routes 99 while [ $# -gt 1 ]; do 100 route delete "$1" "$2" 101 shift; shift 102 done 103 fi 104 105 arp_flush 106} 107 108add_new_routes() { 109 #route add $new_ip_address $LOCALHOST >/dev/null 2>&1 110 for router in $new_routers; do 111 if [ "$new_ip_address" = "$router" ]; then 112 route add default -iface $router >/dev/null 2>&1 113 else 114 route add default $router >/dev/null 2>&1 115 fi 116 # 2nd and subsequent default routers error out, so explicitly 117 # stop processing the list after the first one. 118 break 119 done 120 121 if [ -n "$new_static_routes" ]; then 122 $LOGGER "New Static Routes ($interface): $new_static_routes" 123 set $new_static_routes 124 while [ $# -gt 1 ]; do 125 route add $1 $2 126 shift; shift 127 done 128 fi 129} 130 131add_new_resolv_conf() { 132 # XXX Old code did not create/update resolv.conf unless both 133 # $new_domain_name and $new_domain_name_servers were provided. PR 134 # #3135 reported some ISP's only provide $new_domain_name_servers and 135 # thus broke the script. This code creates the resolv.conf if either 136 # are provided. 137 138 local tmpres=${TMPDIR:-/tmp}/resolv.conf.std 139 rm -f $tmpres 140 141 if [ -n "$new_domain_name" ]; then 142 echo "search $new_domain_name" >>$tmpres 143 fi 144 145 if [ -n "$new_domain_name_servers" ]; then 146 for nameserver in $new_domain_name_servers; do 147 echo "nameserver $nameserver" >>$tmpres 148 done 149 fi 150 151 if [ -f $tmpres ]; then 152 if [ -f /etc/resolv.conf.tail ]; then 153 cat /etc/resolv.conf.tail >>$tmpres 154 fi 155 156 # When resolv.conf is not changed actually, we don't 157 # need to update it. 158 # If /usr is not mounted yet, we cannot use cmp, then 159 # the following test fails. In such case, we simply 160 # ignore an error and do update resolv.conf. 161 if cmp -s $tmpres /etc/resolv.conf; then 162 rm -f $tmpres 163 return 0 164 fi 2>/dev/null 165 166 # In case (e.g. during OpenBSD installs) /etc/resolv.conf 167 # is a symbolic link, take care to preserve the link and write 168 # the new data in the correct location. 169 170 if [ -f /etc/resolv.conf ]; then 171 cat /etc/resolv.conf > /etc/resolv.conf.save 172 fi 173 cat $tmpres > /etc/resolv.conf 174 rm -f $tmpres 175 176 # Try to ensure correct ownership and permissions. 177 chown -RL root:wheel /etc/resolv.conf 178 chmod -RL 644 /etc/resolv.conf 179 180 return 0 181 fi 182 183 return 1 184} 185 186# Must be used on exit. Invokes the local dhcp client exit hooks, if any. 187exit_with_hooks() { 188 exit_status=$1 189 if [ -f /etc/dhclient-exit-hooks ]; then 190 . /etc/dhclient-exit-hooks 191 fi 192 # probably should do something with exit status of the local script 193 exit $exit_status 194} 195 196# 197# Start of active code. 198# 199 200# Invoke the local dhcp client enter hooks, if they exist. 201if [ -f /etc/dhclient-enter-hooks ]; then 202 exit_status=0 203 . /etc/dhclient-enter-hooks 204 # allow the local script to abort processing of this state 205 # local script must set exit_status variable to nonzero. 206 if [ $exit_status -ne 0 ]; then 207 exit $exit_status 208 fi 209fi 210 211if [ -x $NETSTAT ]; then 212 if_defaultroute=`$NETSTAT -rnf inet | $AWK '{if ($1=="default") printf $6}'` 213else 214 if_defaultroute="x" 215fi 216 217case $reason in 218MEDIUM) 219 eval "ifconfig $interface $medium" 220 eval "ifconfig $interface inet -alias 0.0.0.0 $medium" >/dev/null 2>&1 221 sleep 1 222 ;; 223 224PREINIT) 225 delete_old_alias 226 ifconfig $interface inet 0.0.0.0 netmask 0.0.0.0 broadcast 255.255.255.255 up 227 ;; 228 229ARPCHECK|ARPSEND) 230 ;; 231 232BOUND|RENEW|REBIND|REBOOT) 233 check_hostname 234 if [ -n "$old_ip_address" ]; then 235 if [ "$old_ip_address" != "$alias_ip_address" ]; then 236 delete_old_alias 237 fi 238 if [ "$old_ip_address" != "$new_ip_address" ]; then 239 delete_old_address 240 delete_old_routes 241 fi 242 fi 243 if [ "$reason" = BOUND ] || \ 244 [ "$reason" = REBOOT ] || \ 245 [ -z "$old_ip_address" ] || \ 246 [ "$old_ip_address" != "$new_ip_address" ]; then 247 add_new_address 248 add_new_routes 249 fi 250 if [ "$new_ip_address" != "$alias_ip_address" ]; then 251 add_new_alias 252 fi 253 add_new_resolv_conf 254 ;; 255 256EXPIRE|FAIL) 257 delete_old_alias 258 if [ -n "$old_ip_address" ]; then 259 delete_old_address 260 delete_old_routes 261 fi 262 if [ -x $ARP ]; then 263 $ARP -d -a -i $interface 264 fi 265 # XXX Why add alias we just deleted above? 266 add_new_alias 267 if [ -f /etc/resolv.conf.save ]; then 268 cat /etc/resolv.conf.save > /etc/resolv.conf 269 fi 270 ;; 271 272TIMEOUT) 273 delete_old_alias 274 add_new_address 275 sleep 1 276 if [ -n "$new_routers" ]; then 277 $LOGGER "New Routers ($interface): $new_routers" 278 set "$new_routers" 279 if ping -q -c 1 -t 1 "$1"; then 280 if [ "$new_ip_address" != "$alias_ip_address" ]; then 281 add_new_alias 282 fi 283 add_new_routes 284 if add_new_resolv_conf; then 285 exit_with_hooks 0 286 fi 287 fi 288 fi 289 eval "ifconfig $interface inet -alias $new_ip_address $medium" 290 delete_old_routes 291 exit_with_hooks 1 292 ;; 293esac 294 295exit_with_hooks 0 296