#!/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

LOCALHOST=::1

if [ -x /usr/bin/logger ]; then
	LOGGER="/usr/bin/logger -s -p user.notice -t dhclient6"
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
}

delete_old_states() {
	$LOGGER "Starting delete_old_states()"
	# If the IP changed, remove states from the old one
	if [ -f /var/db/${interface}_ipv6 ]; then
		OLD_IPv6 = `cat /var/db/${interface}_ipv6`
		$LOGGER "Comparing IPv6s: Old: ${OLD_IPv6} New: ${new_ip6_address}"
		if [ -n "${OLD_IPv6}" ] && [ "${OLD_IPv6}" != "${new_ip6_address}" ]; then
			$LOGGER "Removing states from old IPv6 '${OLD_IPv6}' (new IP '${new_ip6_address}')"
			/sbin/pfctl -k :: -k ${OLD_IPv6}/128
			/sbin/pfctl -k ${OLD_IPv6}/128
			pfctl -K ${OLD_IPv6}/128
		fi
	fi
	# Delete states through old gateway if it's not the same
	# FIXME: dhcp6 doesn't know about routers. Needs fixing elsewhere.
}

delete_old_address() {
	/bin/rm -f /var/db/${interface}_ipv6
	$IFCONFIG $interface inet6 -alias $old_ip6_address
}

add_new_address() {
	if [ -z $new_ip6_address ]; then
		return;
	fi

	$LOGGER "Starting add_new_address()"
	$LOGGER "ifconfig $interface inet6 $new_ip6_address prefixlen $new_ip6_prefixlen"
	$IFCONFIG $interface \
		inet6 $new_ip6_address \
		prefixlen $new_ip6_prefixlen

		$LOGGER "New IPv6 Address ($interface): $new_ip6_address"
		$LOGGER "New Prefix Length ($interface): $new_ip6_prefixlen"

	echo $new_ip6_address > /var/db/${interface}_ipv6
}

add_new_prefix() {
	if [ -z $new_ip6_prefix ]; then
		return
	fi
	$LOGGER "Starting add_new_prefix()"
	echo $new_ip6_prefix > /var/db/${interface}_pd_ipv6
}

delete_old_prefix() {
	if [ -z $old_ip6_prefix ]; then
		return
	fi
	$LOGGER "Starting delete_old_prefix()"
	rm -f /var/db/${interface}_pd_ipv6
}

delete_old_alias() {
	if [ -n "$alias_ip6_address" ]; then
		$IFCONFIG $interface inet6 -alias $alias_ip6_address > /dev/null 2>&1
		$ROUTE delete -inet6 $alias_ip6_address $LOCALHOST > /dev/null 2>&1
	fi
}

add_new_alias() {
	if [ -n "$alias_ip6_address" ]; then
		$IFCONFIG $interface inet6 alias $alias_ip6_address prefixlen $new_ip6_prefixlen
		$ROUTE add -inet6 $alias_ip6_address $LOCALHOST
	fi
}

add_new_resolv_conf() {
	$LOGGER "Creating resolv.conf"
	if [ -f "/var/etc/nameserver_v6$interface" ]; then
		# Remove old entries
		for nameserver in `cat /var/etc/nameserver_v6$interface`; do
			$ROUTE delete -inet6 $nameserver >/dev/null 2>&1
		done
	fi
	if [ -n "$new_dhcp6_name_servers" ]; then 
		/bin/rm -f /var/etc/nameserver_v6$interface
		ALLOWOVERRIDE=`/usr/bin/grep dnsallowoverride /conf/config.xml | /usr/bin/wc -l`
		for nameserver in $new_dhcp6_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 $nameserver >>/var/etc/nameserver_v6$interface
				$ROUTE add -inet6 $nameserver -iface $interface
			fi
		done
		echo $new_dhcp6_domain_search >/var/etc/searchdomain_v6$interface
	fi

	return 0
}

# Notify rc.newwanip of changes to an interface
notify_rc_newwanipv6() {
	/etc/rc.newwanipv6 $interface
	# /usr/local/sbin/pfSctl -c "interface newipv6 $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

$LOGGER $reason
case $reason in
PREINIT6)
	delete_old_alias
	delete_old_prefix
	$IFCONFIG $interface inet6 up
	delete_old_states
	;;

BOUND6|RENEW6|REBIND6|REBOOT6)

	set
	check_hostname
	changes="no"
	if [ "$old_ip6_address" != "$new_ip6_address" ]; then
		delete_old_states
	fi
	if [ -n "$old_ip6_address" ]; then
		if [ "$old_ip6_address" != "$alias_ip6_address" ]; then
			delete_old_alias
			changes="yes"
		fi
	fi
	if [ "$old_ip6_prefix" != "$new_ip6_prefix" ]; then
		delete_old_prefix
		changes="yes"
	fi
	if [ "$reason" = BOUND6 ] || \
	   [ "$reason" = REBOOT6 ] || \
	   [ "$reason" = REBIND6 ] || \
	   [ -z "$old_ip6_address" ] || \
	   [ "$old_ip6_address" || "$new_ip6_address" ]; then
		add_new_address
		add_new_prefix
		changes="yes"
	fi
	if [ -n "$alias_ip6_address" ] && \
		[ "$new_ip6_address" != "$alias_ip6_address" ]; then
		add_new_alias
		changes="yes"
	fi
	add_new_resolv_conf
	if [ "$changes" = "yes" ] ; then
		notify_rc_newwanipv6
	fi
	;;

EXPIRE6|FAIL6)
	delete_old_alias
	delete_old_states
	if [ -n "$old_ip6_address" ]; then
		delete_old_address
	fi
	;;

TIMEOUT6)
	delete_old_alias
	add_new_address
	/bin/sleep 1
	$IFCONFIG $interface inet6 -alias $new_ip6_address $medium
	delete_old_states
	;;
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