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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
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_search" ]; then
echo "search $new_domain_search" >>$tmpres
elif [ -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
case $resolvconf_enable in
# "no", "false", "off", or "0"
[Nn][Oo]|[Ff][Aa][Ll][Ss][Ee]|[Oo][Ff][Ff]|0)
# 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
# Try to ensure correct ownership and permissions.
chown -RL root:wheel /etc/resolv.conf
chmod -RL 644 /etc/resolv.conf
;;
*)
/sbin/resolvconf -a ${interface} < $tmpres
;;
esac
rm -f $tmpres
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
: ${resolvconf_enable="YES"}
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
case $resolvconf_enable in
# "no", "false", "off", or "0"
[Nn][Oo]|[Ff][Aa][Ll][Ss][Ee]|[Oo][Ff][Ff]|0)
if [ -f /etc/resolv.conf.save ]; then
cat /etc/resolv.conf.save > /etc/resolv.conf
fi
;;
*)
/sbin/resolvconf -d ${interface}
;;
esac
fi
;;
TIMEOUT)
delete_old_alias
add_new_address
sleep 1
if [ -n "$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
|