dhclient-script revision 154164
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 154164 2006-01-10 05:33:33Z 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 $new_domain_name_servers and 135 # thus broke the script. This code creates the resolv.conf if either 136 # are provided. 137 138 rm -f /etc/resolv.conf.std 139 140 if [ -n "$new_domain_name" ]; then 141 echo "search $new_domain_name" >>/etc/resolv.conf.std 142 fi 143 144 if [ -n "$new_domain_name_servers" ]; then 145 for nameserver in $new_domain_name_servers; do 146 echo "nameserver $nameserver" >>/etc/resolv.conf.std 147 done 148 fi 149 150 if [ -f /etc/resolv.conf.std ]; then 151 if [ -f /etc/resolv.conf.tail ]; then 152 cat /etc/resolv.conf.tail >>/etc/resolv.conf.std 153 fi 154 155 # When resolv.conf is not changed actually, we don't 156 # need to update it. 157 # If /usr is not mounted yet, we cannot use cmp, then 158 # the following test fails. In such case, we simply 159 # ignore an error and do update resolv.conf. 160 if cmp -s /etc/resolv.conf.std /etc/resolv.conf; then 161 rm -f /etc/resolv.conf.std 162 return 0 163 fi 2>/dev/null 164 165 # In case (e.g. during OpenBSD installs) /etc/resolv.conf 166 # is a symbolic link, take care to preserve the link and write 167 # the new data in the correct location. 168 169 if [ -f /etc/resolv.conf ]; then 170 cat /etc/resolv.conf > /etc/resolv.conf.save 171 fi 172 cat /etc/resolv.conf.std > /etc/resolv.conf 173 rm -f /etc/resolv.conf.std 174 175 # Try to ensure correct ownership and permissions. 176 chown -RL root:wheel /etc/resolv.conf 177 chmod -RL 644 /etc/resolv.conf 178 179 return 0 180 fi 181 182 return 1 183} 184 185# Must be used on exit. Invokes the local dhcp client exit hooks, if any. 186exit_with_hooks() { 187 exit_status=$1 188 if [ -f /etc/dhclient-exit-hooks ]; then 189 . /etc/dhclient-exit-hooks 190 fi 191 # probably should do something with exit status of the local script 192 exit $exit_status 193} 194 195# 196# Start of active code. 197# 198 199# Invoke the local dhcp client enter hooks, if they exist. 200if [ -f /etc/dhclient-enter-hooks ]; then 201 exit_status=0 202 . /etc/dhclient-enter-hooks 203 # allow the local script to abort processing of this state 204 # local script must set exit_status variable to nonzero. 205 if [ $exit_status -ne 0 ]; then 206 exit $exit_status 207 fi 208fi 209 210if [ -x $NETSTAT ]; then 211 if_defaultroute=`$NETSTAT -rnf inet | $AWK '{if ($1=="default") printf $6}'` 212else 213 if_defaultroute="x" 214fi 215 216case $reason in 217MEDIUM) 218 eval "ifconfig $interface $medium" 219 eval "ifconfig $interface inet -alias 0.0.0.0 $medium" >/dev/null 2>&1 220 sleep 1 221 ;; 222 223PREINIT) 224 delete_old_alias 225 ifconfig $interface inet 0.0.0.0 netmask 0.0.0.0 broadcast 255.255.255.255 up 226 ;; 227 228ARPCHECK|ARPSEND) 229 ;; 230 231BOUND|RENEW|REBIND|REBOOT) 232 check_hostname 233 if [ -n "$old_ip_address" ]; then 234 if [ "$old_ip_address" != "$alias_ip_address" ]; then 235 delete_old_alias 236 fi 237 if [ "$old_ip_address" != "$new_ip_address" ]; then 238 delete_old_address 239 delete_old_routes 240 fi 241 fi 242 if [ "$reason" = BOUND ] || \ 243 [ "$reason" = REBOOT ] || \ 244 [ -z "$old_ip_address" ] || \ 245 [ "$old_ip_address" != "$new_ip_address" ]; then 246 add_new_address 247 add_new_routes 248 fi 249 if [ "$new_ip_address" != "$alias_ip_address" ]; then 250 add_new_alias 251 fi 252 add_new_resolv_conf 253 ;; 254 255EXPIRE|FAIL) 256 delete_old_alias 257 if [ -n "$old_ip_address" ]; then 258 delete_old_address 259 delete_old_routes 260 fi 261 if [ -x $ARP ]; then 262 $ARP -d -a -i $interface 263 fi 264 # XXX Why add alias we just deleted above? 265 add_new_alias 266 if [ -f /etc/resolv.conf.save ]; then 267 cat /etc/resolv.conf.save > /etc/resolv.conf 268 fi 269 ;; 270 271TIMEOUT) 272 delete_old_alias 273 add_new_address 274 sleep 1 275 if [ -n "$new_routers" ]; then 276 $LOGGER "New Routers ($interface): $new_routers" 277 set "$new_routers" 278 if ping -q -c 1 -w 1 "$1"; then 279 if [ "$new_ip_address" != "$alias_ip_address" ]; then 280 add_new_alias 281 fi 282 add_new_routes 283 if add_new_resolv_conf; then 284 exit_with_hooks 0 285 fi 286 fi 287 fi 288 eval "ifconfig $interface inet -alias $new_ip_address $medium" 289 delete_old_routes 290 exit_with_hooks 1 291 ;; 292esac 293 294exit_with_hooks 0 295