UnivNautes

#!/bin/sh

# $Id$

# $OpenBSD: dhclient-script,v 1.6 2004/05/06 18:22:41 claudio Exp $

# $FreeBSD: src/sbin/dhclient/dhclient-script,v 1.4 2005/06/10 03:41:18 brooks Exp $

#

# 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.

#

NETSTAT=/usr/bin/netstat

GREP=/usr/bin/grep

AWK=/usr/bin/awk

HOSTNAME=/bin/hostname

GREP=/usr/bin/grep

ROUTE=/sbin/route

SED=/usr/bin/sed

ARP=/usr/sbin/arp

IFCONFIG=/sbin/ifconfig

PFCTL=/sbin/pfctl

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" ] || \

	   [ "$current_hostname" = "$old_host_name" -a \

	     "$new_hostname" != "$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' | \

		/bin/sh >/dev/null 2>&1

}

# NOTE: use of the below has been disabled because rc.newwanip handles this correctly and this

# unnecessarily killed states in multiple circumstances. Leaving here for now, should be safe

# to remove later.  -cmb 20141105

delete_old_states() {

	$LOGGER "Starting delete_old_states()"

	_FLUSHED=0

	# If the IP changed, remove states from the old one

	if [ -f /var/db/${interface}_ip ]; then

		OLD_IP=`cat /var/db/${interface}_ip`

		$LOGGER "Comparing IPs: Old: ${OLD_IP} New: ${new_ip_address}"

		if [ -n "${OLD_IP}" ] && [ "${OLD_IP}" != "${new_ip_address}" ]; then

			$LOGGER "Removing states from old IP '${OLD_IP}' (new IP '${new_ip_address}')"

			${PFCTL} -i $interface -Fs

			${PFCTL} -K ${OLD_IP}/32

			_FLUSHED=1

		fi

	fi

	# Delete states through old gateway if it's not the same

	OLD_ROUTER=""

	if [ -n "${old_routers}" ]; then

		OLD_ROUTER=$old_routers

	elif [ -f /tmp/${interface}_router ]; then

		OLD_ROUTER=`cat /tmp/${interface}_router`

	fi

	if [ ${_FLUSHED} -eq 0 -a -n "${OLD_ROUTER}" ]; then

		$LOGGER "Comparing Routers: Old: ${OLD_ROUTER} New: ${new_routers}"

		if [ "${OLD_ROUTER}" != "${new_routers}" ]; then

			$LOGGER "Removing states through old gateway '${OLD_ROUTER}' (new gateway '${new_routers}')"

			${PFCTL} -i $interface -Fs

		fi

	fi

}

delete_old_address() {

	/bin/rm -f /var/db/${interface}_ip

	$IFCONFIG $interface inet -alias $old_ip_address $medium

}

add_new_address() {

	$LOGGER "Starting add_new_address()"

	$LOGGER "ifconfig $interface inet $new_ip_address netmask $new_subnet_mask broadcast $new_broadcast_address $medium"

	$IFCONFIG $interface \

		inet $new_ip_address \

		netmask $new_subnet_mask \

		broadcast $new_broadcast_address \

		$medium

	$IFCONFIG $interface setfirst $new_ip_address

	$LOGGER "New IP Address ($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"

	# This is necessary otherwise apinger will try to ping all 1s address

	if [ -n "$new_routers" ] && [ "$new_routers" != "255.255.255.255" ]; then

		echo $new_routers > /tmp/${interface}_router

	fi

	echo $new_ip_address > /var/db/${interface}_ip

}

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() {

	$LOGGER "Deleting old routes"

	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

	# Only allow the default route to be overridden if it's on our own interface

	if [ -f "/tmp/${interface}_defaultgw" ]; then

		for router in $old_routers; do

			$ROUTE delete default $router >/dev/null 2>&1

			/bin/rm -f /tmp/${interface}_router

		done

	fi

	if [ -n "$old_static_routes" ]; then

		set $old_static_routes

		while [ $# -gt 1 ]; do

			$ROUTE delete "$1" "$2"

			shift; shift

                        /bin/rm -f /tmp/${interface}_router

		done

	fi

	arp_flush

}

add_new_routes() {

	$LOGGER "Adding new routes to interface: $interface"

	# 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

	ADDED_ROUTE=no

	EXISTSGW=`/bin/ls -l /tmp/*_defaultgw | /usr/bin/wc -l`

	# Only allow the default route to be overridden if it's on our own interface

	if [ -f "/tmp/${interface}_defaultgw" -o $EXISTSGW -eq 0 ]; then

		$ROUTE delete default

		for router in $new_routers; do

			if [ "$new_ip_address" = "$router" -o "$router" = "255.255.255.255" ]; then

				$ROUTE add default -iface $interface

				echo $ROUTE add default -iface $interface | $LOGGER

				# NOTE: Do not activate this for all ones address since pf(4) will try to forward packets to it.

				if [ "$new_ip_address" = "$router" ]; then

					echo $router > /tmp/${interface}_router

				fi

			else

				$ROUTE add default $router

				echo $ROUTE add default $router | $LOGGER

                       		echo $router > /tmp/${interface}_router

			fi

			ADDED_ROUTE=yes

			# 2nd and subsequent default routers error out, so explicitly

			# stop processing the list after the first one.

			break

		done

	fi

	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

			if [ "$ADDED_ROUTE" = "no" ]; then

                        	echo $2 > /tmp/${interface}_router

			fi

			shift; shift

		done

	fi

}

add_new_resolv_conf() {

	$LOGGER "Creating resolv.conf"

	if [ -f "/var/etc/nameserver_$interface" ]; then

		# Remove old entries

		for nameserver in `cat /var/etc/nameserver_$interface`; do

			$ROUTE delete $nameserver >/dev/null 2>&1

		done

	fi

	if [ -n "$new_domain_name_servers" ]; then 

		/bin/rm -f /var/etc/nameserver_$interface

		ALLOWOVERRIDE=`/usr/bin/grep dnsallowoverride /conf/config.xml | /usr/bin/wc -l`

		for nameserver in $new_domain_name_servers; do

			# Add a route to the nameserver out the correct interface

			# so that mulitple wans work correctly with multiple dns

			# also backup the nameserver for later route removal

			if [ $ALLOWOVERRIDE -gt 0 ]; then

				echo $nameserver >>/var/etc/nameserver_$interface

				$ROUTE add $nameserver -iface $interface

			fi

		done

		echo $new_domain_name >/var/etc/searchdomain_$interface

	fi

	return 0

}

# Notify rc.newwanip of changes to an interface

notify_rc_newwanip() {

	/usr/local/sbin/pfSctl -c "interface newip $interface"

}

#

# Start of active code.

#

# Invoke the local dhcp client enter hooks, if they exist.

if [ -f /etc/dhclient-enter-hooks ]; then

	$LOGGER "dhclient-enter-hooks"

	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 $ROUTE ]; then

#	if_defaultroute=`$ROUTE -n get -inet default | $GREP interface | $AWK '{print $2}'`

#else

#	$LOGGER "if_defaultroute"

#	if_defaultroute="x"

#fi

$LOGGER $reason

case $reason in

MEDIUM)

	$IFCONFIG $interface $medium

	$IFCONFIG $interface inet -alias 0.0.0.0 $medium >/dev/null 2>&1

	/bin/sleep 1

	;;

PREINIT)

	delete_old_alias

	$IFCONFIG $interface inet 0.0.0.0 netmask 255.255.255.255 broadcast 255.255.255.255 up

	/bin/rm -f /tmp/${interface}_router

	;;

ARPCHECK|ARPSEND)

	;;

BOUND|RENEW|REBIND|REBOOT)

	check_hostname

	changes="no"

	if [ -n "$old_ip_address" ]; then

		if [ -n "$alias_ip_address" ] && \

		   [ "$old_ip_address" != "$alias_ip_address" ]; then

			delete_old_alias

			changes="yes"

		fi

		if [ "$old_ip_address" != "$new_ip_address" ]; then

			delete_old_address

			delete_old_routes

			changes="yes"

		fi

	fi

	if [ "$reason" = BOUND ] || \

	   [ "$reason" = REBOOT ] || \

	   [ -z "$old_ip_address" ] || \

	   [ "$old_ip_address" != "$new_ip_address" ]; then

		add_new_address

		add_new_routes

		changes="yes"

	fi

	if [ -n "$alias_ip_address" ] && \

       [ "$new_ip_address" != "$alias_ip_address" ]; then

		add_new_alias

		changes="yes"

	fi

	add_new_resolv_conf

	if [ "$changes" = "yes" ] ; then

		notify_rc_newwanip

	fi

	;;

EXPIRE|FAIL)

	delete_old_alias

	if [ -n "$old_ip_address" ]; then

		delete_old_address

		delete_old_routes

	fi

	;;

TIMEOUT)

	delete_old_alias

	add_new_address

	/bin/sleep 1

	if [ -n "$new_routers" ]; then

		$LOGGER "New Routers ($interface): $new_routers"

		set "$new_routers"

		if /sbin/ping -q -c 1 -t 1 "$1"; then

			if [ "$new_ip_address" != "$alias_ip_address" ]; then

				add_new_alias

			fi

			add_new_routes

			if add_new_resolv_conf; then

				notify_rc_newwanip

			fi

		fi

	fi

	$IFCONFIG $interface inet -alias $new_ip_address $medium

	delete_old_routes

	;;

esac

# Invoke the local dhcp client exit hooks, if they exist.

if [ -f /etc/dhclient-exit-hooks ]; then

	$LOGGER "dhclient-exit-hooks"

	exit_status=0

	. /etc/dhclient-exit-hooks

	# allow the local script to abort processing of this state

	# local script must set exit_status variable to nonzero.

	exit $exit_status

fi