#!/bin/sh # # $OpenBSD: dhclient-script,v 1.6 2004/05/06 18:22:41 claudio Exp $ # $FreeBSD$ # # Copyright (c) 2003 Kenneth R Westerback # # Permission to use, copy, modify, and distribute this software for any # purpose with or without fee is hereby granted, provided that the above # copyright notice and this permission notice appear in all copies. # # THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES # WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF # MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR # ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES # WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN # ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF # OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. # # ARP=/usr/sbin/arp HOSTNAME=/bin/hostname IFCONFIG='/sbin/ifconfig -n' LOCALHOST=127.0.0.1 if [ -x /usr/bin/logger ]; then LOGGER="/usr/bin/logger -s -p user.notice -t dhclient" else LOGGER=echo fi # # Helper functions that implement common actions. # check_hostname() { current_hostname=`$HOSTNAME` if [ -z "$current_hostname" ]; then $LOGGER "New Hostname ($interface): $new_host_name" $HOSTNAME $new_host_name elif [ "$current_hostname" = "$old_host_name" -a \ "$new_host_name" != "$old_host_name" ]; then $LOGGER "New Hostname ($interface): $new_host_name" $HOSTNAME $new_host_name fi } arp_flush() { arp -an -i $interface | \ sed -n -e 's/^.*(\(.*\)) at .*$/arp -d \1/p' | \ sh >/dev/null 2>&1 } delete_old_address() { eval "$IFCONFIG $interface inet -alias $old_ip_address $medium" } add_new_address() { eval "$IFCONFIG $interface \ inet $new_ip_address \ netmask $new_subnet_mask \ broadcast $new_broadcast_address \ $medium" $LOGGER "New IP Address ($interface): $new_ip_address" $LOGGER "New Subnet Mask ($interface): $new_subnet_mask" $LOGGER "New Broadcast Address ($interface): $new_broadcast_address" $LOGGER "New Routers ($interface): $new_routers" } delete_old_alias() { if [ -n "$alias_ip_address" ]; then $IFCONFIG $interface inet -alias $alias_ip_address > /dev/null 2>&1 #route delete $alias_ip_address $LOCALHOST > /dev/null 2>&1 fi } add_new_alias() { if [ -n "$alias_ip_address" ]; then $IFCONFIG $interface inet alias $alias_ip_address netmask \ $alias_subnet_mask #route add $alias_ip_address $LOCALHOST fi } fill_classless_routes() { set $1 while [ $# -ge 5 ]; do if [ $1 -eq 0 ]; then route="default" elif [ $1 -le 8 ]; then route="$2.0.0.0/$1" shift elif [ $1 -le 16 ]; then route="$2.$3.0.0/$1" shift; shift elif [ $1 -le 24 ]; then route="$2.$3.$4.0/$1" shift; shift; shift else route="$2.$3.$4.$5/$1" shift; shift; shift; shift fi shift router="$1.$2.$3.$4" classless_routes="$classless_routes $route $router" shift; shift; shift; shift done } delete_old_routes() { #route delete "$old_ip_address" $LOCALHOST >/dev/null 2>&1 if [ -n "$old_classless_routes" ]; then fill_classless_routes "$old_classless_routes" set $classless_routes while [ $# -gt 1 ]; do route delete "$1" "$2" shift; shift done return 0; fi # If we supported multiple default routes, we'd be removing each # one here. We don't so just delete the default route if it's # through our interface. if is_default_interface; then route delete default >/dev/null 2>&1 fi if [ -n "$old_static_routes" ]; then set $old_static_routes while [ $# -gt 1 ]; do route delete "$1" "$2" shift; shift done fi arp_flush } add_new_routes() { #route add $new_ip_address $LOCALHOST >/dev/null 2>&1 # RFC 3442: If the DHCP server returns both a Classless Static # Routes option and a Router option, the DHCP client MUST ignore # the Router option. # # DHCP clients that support this option (Classless Static Routes) # MUST NOT install the routes specified in the Static Routes # option (option code 33) if both a Static Routes option and the # Classless Static Routes option are provided. if [ -n "$new_classless_routes" ]; then fill_classless_routes "$new_classless_routes" $LOGGER "New Classless Static Routes ($interface): $classless_routes" set $classless_routes while [ $# -gt 1 ]; do if [ "0.0.0.0" = "$2" ]; then route add "$1" -iface "$interface" else route add "$1" "$2" fi shift; shift done return fi for router in $new_routers; do if is_default_interface; then if [ "$new_ip_address" = "$router" ]; then route add default -iface $router >/dev/null 2>&1 else route add default $router >/dev/null 2>&1 fi fi # 2nd and subsequent default routers error out, so explicitly # stop processing the list after the first one. break done if [ -n "$new_static_routes" ]; then $LOGGER "New Static Routes ($interface): $new_static_routes" set $new_static_routes while [ $# -gt 1 ]; do route add $1 $2 shift; shift done fi } add_new_resolv_conf() { # XXX Old code did not create/update resolv.conf unless both # $new_domain_name and $new_domain_name_servers were provided. PR # #3135 reported some ISP's only provide $new_domain_name_servers and # thus broke the script. This code creates the resolv.conf if either # are provided. local tmpres=/var/run/resolv.conf.${interface} rm -f $tmpres if [ -n "$new_domain_name" ]; then echo "search $new_domain_name" >>$tmpres fi if [ -n "$new_domain_name_servers" ]; then for nameserver in $new_domain_name_servers; do echo "nameserver $nameserver" >>$tmpres done fi if [ -f $tmpres ]; then if [ -f /etc/resolv.conf.tail ]; then cat /etc/resolv.conf.tail >>$tmpres fi # When resolv.conf is not changed actually, we don't # need to update it. # If /usr is not mounted yet, we cannot use cmp, then # the following test fails. In such case, we simply # ignore an error and do update resolv.conf. if cmp -s $tmpres /etc/resolv.conf; then rm -f $tmpres return 0 fi 2>/dev/null # In case (e.g. during OpenBSD installs) /etc/resolv.conf # is a symbolic link, take care to preserve the link and write # the new data in the correct location. if [ -f /etc/resolv.conf ]; then cat /etc/resolv.conf > /etc/resolv.conf.save fi cat $tmpres > /etc/resolv.conf rm -f $tmpres # Try to ensure correct ownership and permissions. chown -RL root:wheel /etc/resolv.conf chmod -RL 644 /etc/resolv.conf return 0 fi return 1 } # Must be used on exit. Invokes the local dhcp client exit hooks, if any. exit_with_hooks() { exit_status=$1 if [ -f /etc/dhclient-exit-hooks ]; then . /etc/dhclient-exit-hooks fi # probably should do something with exit status of the local script exit $exit_status } # Get the interface with the current ipv4 default route on it using only # commands that are available prior to /usr being mounted. is_default_interface() { routeget="`route -n get -inet default`" oldifs="$IFS" IFS=" " defif= for line in $routeget ; do case $line in *interface:*) defif=${line##*: } ;; esac done IFS=${oldifs} if [ -z "$defif" -o "$defif" = "$interface" ]; then return 0 else return 1 fi } # # Start of active code. # # Invoke the local dhcp client enter hooks, if they exist. if [ -f /etc/dhclient-enter-hooks ]; then exit_status=0 . /etc/dhclient-enter-hooks # allow the local script to abort processing of this state # local script must set exit_status variable to nonzero. if [ $exit_status -ne 0 ]; then exit $exit_status fi fi case $reason in MEDIUM) eval "$IFCONFIG $interface $medium" eval "$IFCONFIG $interface inet -alias 0.0.0.0 $medium" >/dev/null 2>&1 sleep 1 ;; PREINIT) delete_old_alias $IFCONFIG $interface inet alias 0.0.0.0 netmask 0.0.0.0 broadcast 255.255.255.255 up ;; ARPCHECK|ARPSEND) ;; BOUND|RENEW|REBIND|REBOOT) check_hostname if [ -n "$old_ip_address" ]; then if [ "$old_ip_address" != "$alias_ip_address" ]; then delete_old_alias fi if [ "$old_ip_address" != "$new_ip_address" ]; then delete_old_address delete_old_routes fi fi if [ "$reason" = BOUND ] || \ [ "$reason" = REBOOT ] || \ [ -z "$old_ip_address" ] || \ [ "$old_ip_address" != "$new_ip_address" ]; then add_new_address add_new_routes fi if [ "$new_ip_address" != "$alias_ip_address" ]; then add_new_alias fi if is_default_interface; then add_new_resolv_conf fi ;; EXPIRE|FAIL) delete_old_alias if [ -n "$old_ip_address" ]; then delete_old_address delete_old_routes fi if [ -x $ARP ]; then $ARP -d -a -i $interface fi # XXX Why add alias we just deleted above? add_new_alias if is_default_interface; then if [ -f /etc/resolv.conf.save ]; then cat /etc/resolv.conf.save > /etc/resolv.conf fi fi ;; TIMEOUT) delete_old_alias add_new_address sleep 1 if [ -n "$new_routers" ]; then $LOGGER "New Routers ($interface): $new_routers" set "$new_routers" if ping -q -c 1 -t 1 "$1"; then if [ "$new_ip_address" != "$alias_ip_address" ]; then add_new_alias fi add_new_routes if ! is_default_interface; then exit_with_hooks 0 fi if add_new_resolv_conf; then exit_with_hooks 0 fi fi fi eval "$IFCONFIG $interface inet -alias $new_ip_address $medium" delete_old_routes exit_with_hooks 1 ;; esac exit_with_hooks 0