freebsd-dev/sbin/dhclient/dhclient-script
Brooks Davis b1f35e43b1 When we give up on an interface, use the arp(8) command to remove all
entries from the interface rather than using ifconfig's delete command.
This preserves non-dhclient configured addresses (though they are wiped
out when dhclient is restarted).

MFC after:	1 week
2006-01-10 05:33:33 +00:00

295 lines
7.3 KiB
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#!/bin/sh
#
# $OpenBSD: dhclient-script,v 1.6 2004/05/06 18:22:41 claudio Exp $
# $FreeBSD$
#
# Copyright (c) 2003 Kenneth R Westerback <krw@openbsd.org>
#
# 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
AWK=/usr/bin/awk
HOSTNAME=/bin/hostname
NETSTAT=/usr/bin/netstat
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 $LOCALHOST
fi
}
delete_old_routes() {
#route delete "$old_ip_address" $LOCALHOST >/dev/null 2>&1
for router in $old_routers; do
if [ $if_defaultroute = x -o $if_defaultroute = $interface ]; then
route delete default $route >/dev/null 2>&1
fi
done
if [ -n "$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
for router in $new_routers; do
if [ "$new_ip_address" = "$router" ]; then
route add default -iface $router >/dev/null 2>&1
else
route add default $router >/dev/null 2>&1
fi
# 2nd and subsequent default routers error out, so explicitly
# stop processing the list after the first one.
break
done
if [ -n "$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 $new_domain_name_servers and
# thus broke the script. This code creates the resolv.conf if either
# are provided.
rm -f /etc/resolv.conf.std
if [ -n "$new_domain_name" ]; then
echo "search $new_domain_name" >>/etc/resolv.conf.std
fi
if [ -n "$new_domain_name_servers" ]; then
for nameserver in $new_domain_name_servers; do
echo "nameserver $nameserver" >>/etc/resolv.conf.std
done
fi
if [ -f /etc/resolv.conf.std ]; then
if [ -f /etc/resolv.conf.tail ]; then
cat /etc/resolv.conf.tail >>/etc/resolv.conf.std
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 /etc/resolv.conf.std /etc/resolv.conf; then
rm -f /etc/resolv.conf.std
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 /etc/resolv.conf.std > /etc/resolv.conf
rm -f /etc/resolv.conf.std
# 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
}
#
# 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
if [ -x $NETSTAT ]; then
if_defaultroute=`$NETSTAT -rnf inet | $AWK '{if ($1=="default") printf $6}'`
else
if_defaultroute="x"
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 $interface inet 0.0.0.0 netmask 0.0.0.0 broadcast 255.255.255.255 up
;;
ARPCHECK|ARPSEND)
;;
BOUND|RENEW|REBIND|REBOOT)
check_hostname
if [ -n "$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" != "$alias_ip_address" ]; then
add_new_alias
fi
add_new_resolv_conf
;;
EXPIRE|FAIL)
delete_old_alias
if [ -n "$old_ip_address" ]; then
delete_old_address
delete_old_routes
fi
if [ -x $ARP ]; then
$ARP -d -a -i $interface
fi
# XXX Why add alias we just deleted above?
add_new_alias
if [ -f /etc/resolv.conf.save ]; then
cat /etc/resolv.conf.save > /etc/resolv.conf
fi
;;
TIMEOUT)
delete_old_alias
add_new_address
sleep 1
if [ -n "$new_routers" ]; then
$LOGGER "New Routers ($interface): $new_routers"
set "$new_routers"
if ping -q -c 1 -w 1 "$1"; then
if [ "$new_ip_address" != "$alias_ip_address" ]; then
add_new_alias
fi
add_new_routes
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