HardenedBSD/etc/rc.network6

#! /bin/sh
#
# Copyright (c) 2000  The KAME Project
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
#
# $FreeBSD$
#

# Note that almost all of the user-configurable behavior is not in this
# file, but rather in /etc/defaults/rc.conf.  Please check that file
# first before contemplating any changes here.  If you do need to change
# this file for some reason, we would like to know about it.

hexdigit () {
	if [ $1 -lt 10 ]; then
		echo $1
	else
		case $1 in
		10)	echo a ;;
		11)	echo b ;;
		12)	echo c ;;
		13)	echo d ;;
		14)	echo e ;;
		15)	echo f ;;
		esac
	fi
}

hexprint () {
	val=$1
	str=''

	dig=`hexdigit $((${val} & 15))`
	str=${dig}${str}
	val=$((${val} >> 4))
	while [ ${val} -gt 0 ]; do
		dig=`hexdigit $((${val} & 15))`
		str=${dig}${str}
		val=$((${val} >> 4))
	done

	echo ${str}
}

# IPv6 startup

network6_pass1() {
	echo -n 'Doing IPv6 network setup:'

	# Initialize IP filtering using ip6fw
	#
	if /sbin/ip6fw -q flush > /dev/null 2>&1; then
		ipv6_firewall_in_kernel=1
	else
		ipv6_firewall_in_kernel=0
	fi

	case ${ipv6_firewall_enable} in
	[Yy][Ee][Ss])
		if [ "${ipv6_firewall_in_kernel}" -eq 0 ] && kldload ip6fw; then
			ipv6_firewall_in_kernel=1
			echo "Kernel IPv6 firewall module loaded."
		elif [ "${ipv6_firewall_in_kernel}" -eq 0 ]; then
			echo "Warning: IPv6 firewall kernel module failed to load."
		fi
		;;
	esac

	# Load the filters if required
	#
	case ${ipv6_firewall_in_kernel} in
	1)
		if [ -z "${ipv6_firewall_script}" ]; then
			ipv6_firewall_script=/etc/rc.firewall6
		fi

		case ${ipv6_firewall_enable} in
		[Yy][Ee][Ss])
			if [ -r "${ipv6_firewall_script}" ]; then
				. "${ipv6_firewall_script}"
				echo -n 'IPv6 Firewall rules loaded.'
			elif [ "`ip6fw l 65535`" = "65535 deny ipv6 from any to any" ]; then
				echo -n "Warning: kernel has IPv6 firewall functionality, "
				echo "but IPv6 firewall rules are not enabled."
				echo "		 All ipv6 services are disabled."
			fi

			case ${ipv6_firewall_logging} in
			[Yy][Ee][Ss] | '')
				echo 'IPv6 Firewall logging=YES'
				sysctl net.inet6.ip6.fw.verbose=1 >/dev/null
				;;
			*)
				;;
			esac

			;;
		esac
		;;
	esac

	case ${ipv6_network_interfaces} in
	[Aa][Uu][Tt][Oo])
		#
		# list of interfaces, and prefix for interfaces
		#
		ipv6_network_interfaces="`ifconfig -l`"
		;;
	esac

	# just to make sure
	ifconfig lo0 up

	# disallow "internal" addresses to appear on the wire
	route add -inet6 ::ffff:0.0.0.0 -prefixlen 96 ::1 -reject
	route add -inet6 ::0.0.0.0 -prefixlen 96 ::1 -reject

	case ${ipv6_gateway_enable} in
	[Yy][Ee][Ss])
		# act as a router
		sysctl net.inet6.ip6.forwarding=1
		sysctl net.inet6.ip6.accept_rtadv=0

		# wait for DAD
		for i in $ipv6_network_interfaces; do
			ifconfig $i up
		done
		sleep `sysctl -n net.inet6.ip6.dad_count`
		sleep 1
		;;
	*)
		# act as endhost - start with manual configuration
		sysctl net.inet6.ip6.forwarding=0
		sysctl net.inet6.ip6.accept_rtadv=0
		;;
	esac

	# setting up interfaces
	network6_interface_setup $ipv6_network_interfaces

	# wait for DAD's completion (for global addrs)
	sleep `sysctl -n net.inet6.ip6.dad_count`
	sleep 1

	case ${ipv6_gateway_enable} in
	[Yy][Ee][Ss])
		# Filter out interfaces on which IPv6 addr init failed.
		ipv6_working_interfaces=""
		for i in ${ipv6_network_interfaces}; do
			laddr=`network6_getladdr $i exclude_tentative`
			case ${laddr} in
			'')
				;;
			*)
				ipv6_working_interfaces="$i \
					${ipv6_working_interfaces}"
				;;
			esac
		done
		ipv6_network_interfaces=${ipv6_working_interfaces}
		;;
	esac

	# 6to4 setup
	network6_stf_setup

	# install the "default interface" to kernel, which will be used
	# as the default route when there's no router.
	network6_default_interface_setup

	# setup static routes
	network6_static_routes_setup

	# setup faith
	network6_faith_setup

	case ${ipv6_gateway_enable} in
	[Yy][Ee][Ss])
		# ipv6_router
		case ${ipv6_router_enable} in
		[Yy][Ee][Ss])
			if [ -x ${ipv6_router} ]; then
				echo -n " ${ipv6_router}"
				${ipv6_router} ${ipv6_router_flags}
			fi
			;;
		esac

		# rtadvd
		# This should enabled with a great care.
		# You may want to fine-tune /etc/rtadvd.conf.
		#
		# And if you wish your rtadvd to receive and process
		# router renumbering messages, specify your Router Renumbering
		# security policy by -R option.
		#
		# See `man 3 ipsec_set_policy` for IPsec policy specification
		# details.
		# (CAUTION: This enables your routers prefix renumbering
		# from another machine, so if you enable this, do it with
		# enough care.)
		#
		case ${rtadvd_enable} in
		[Yy][Ee][Ss])
			# default
			case ${rtadvd_interfaces} in
			'')
				for i in ${ipv6_network_interfaces}; do
					case $i in
					lo0|gif[0-9]*|stf[0-9]*|faith[0-9]*|lp[0-9]*|sl[0-9]*|tun[0-9]*)
						continue
						;;
					*)
						rtadvd_interfaces="${rtadvd_interfaces} ${i}"
						;;
					esac
				done
				;;
			esac
			rtadvd ${rtadvd_interfaces}
			#
			# Enable Router Renumbering, unicast case
			# (use correct src/dst addr)
			# rtadvd -R "in ipsec ah/transport/fec0:0:0:1::1-fec0:0:0:10::1/require" \
			#	${ipv6_network_interfaces}
			# Enable Router Renumbering, multicast case
			# (use correct src addr)
			# rtadvd -R "in ipsec ah/transport/ff05::2-fec0:0:0:10::1/require" \
			#	${ipv6_network_interfaces}
			;;
		esac

		# mroute6d
		case ${mroute6d_enable} in
		[Yy][Ee][Ss])
			if [ -x ${mroute6d_program} ]; then
				echo -n " ${mroute6d_program}"
				${mroute6d_program} ${mroute6d_flags}
			fi
			;;
		esac
		;;
	esac

	case ${ipv6_ipv4mapping} in
	[Yy][Ee][Ss])
		echo -n ' IPv4 mapped IPv6 address support=YES'
		sysctl net.inet6.ip6.v6only=0 >/dev/null
		;;
	'' | *)
		echo -n ' IPv4 mapped IPv6 address support=NO'
		sysctl net.inet6.ip6.v6only=1 >/dev/null
		;;
	esac

	echo '.'

	# Let future generations know we made it.
	#
	network6_pass1_done=YES
}

network6_interface_setup() {
	interfaces=$*
	rtsol_interfaces=''
	case ${ipv6_gateway_enable} in
	[Yy][Ee][Ss])
		rtsol_available=no
		;;
	*)
		rtsol_available=yes
		;;
	esac
	for i in $interfaces; do
		rtsol_interface=yes
		eval prefix=\$ipv6_prefix_$i
		if [ -n "${prefix}" ]; then
			rtsol_available=no
			rtsol_interface=no
			laddr=`network6_getladdr $i`
			hostid=`expr "${laddr}" : 'fe80::\(.*\)%\(.*\)'`
			for j in ${prefix}; do
				address=$j\:${hostid}
				ifconfig $i inet6 ${address} prefixlen 64 alias

				case ${ipv6_gateway_enable} in
				[Yy][Ee][Ss])
					# subnet-router anycast address
					# (rfc2373)
					ifconfig $i inet6 $j:: prefixlen 64 \
						alias anycast
					;;
				esac
			done
		fi
		eval ipv6_ifconfig=\$ipv6_ifconfig_$i
		if [ -n "${ipv6_ifconfig}" ]; then
			rtsol_available=no
			rtsol_interface=no
			ifconfig $i inet6 ${ipv6_ifconfig} alias
		fi

		if [ ${rtsol_available} = yes -a ${rtsol_interface} = yes ]
		then
			case ${i} in
			lo0|gif[0-9]*|stf[0-9]*|faith[0-9]*|lp[0-9]*|sl[0-9]*|tun[0-9]*)
				;;
			*)
				rtsol_interfaces="${rtsol_interfaces} ${i}"
				;;
			esac
		else
			ifconfig $i inet6
		fi
	done

	if [ ${rtsol_available} = yes -a -n "${rtsol_interfaces}" ]; then
		# Act as endhost - automatically configured.
		# You can configure only single interface, as
		# specification assumes that autoconfigured host has
		# single interface only.
		sysctl net.inet6.ip6.accept_rtadv=1
		set ${rtsol_interfaces}
		ifconfig $1 up
		rtsol $1
	fi

	for i in $interfaces; do
		alias=0
		while : ; do
			eval ipv6_ifconfig=\$ipv6_ifconfig_${i}_alias${alias}
			if [ -z "${ipv6_ifconfig}" ]; then
				break;
			fi
			ifconfig $i inet6 ${ipv6_ifconfig} alias
			alias=$((${alias} + 1))
		done
	done
}

network6_stf_setup() {
	case ${stf_interface_ipv4addr} in
	[Nn][Oo] | '')
		;;
	*)
		# assign IPv6 addr and interface route for 6to4 interface
		stf_prefixlen=$((16+${stf_interface_ipv4plen:-0}))
		OIFS="$IFS"
		IFS=".$IFS"
		set ${stf_interface_ipv4addr}
		IFS="$OIFS"
		hexfrag1=`hexprint $(($1*256 + $2))`
		hexfrag2=`hexprint $(($3*256 + $4))`
		ipv4_in_hexformat="${hexfrag1}:${hexfrag2}"
		case ${stf_interface_ipv6_ifid} in
		[Aa][Uu][Tt][Oo] | '')
			for i in ${ipv6_network_interfaces}; do
				laddr=`network6_getladdr ${i}`
				case ${laddr} in
				'')
					;;
				*)
					break
					;;
				esac
			done
			stf_interface_ipv6_ifid=`expr "${laddr}" : \
						      'fe80::\(.*\)%\(.*\)'`
			case ${stf_interface_ipv6_ifid} in
			'')
				stf_interface_ipv6_ifid=0:0:0:1
				;;
			esac
			;;
		esac
		ifconfig stf0 inet6 2002:${ipv4_in_hexformat}:${stf_interface_ipv6_slaid:-0}:${stf_interface_ipv6_ifid} \
			prefixlen ${stf_prefixlen}
		# disallow packets to malicious 6to4 prefix
		route add -inet6 2002:e000:: -prefixlen 20 ::1 -reject
		route add -inet6 2002:7f00:: -prefixlen 24 ::1 -reject
		route add -inet6 2002:0000:: -prefixlen 24 ::1 -reject
		route add -inet6 2002:ff00:: -prefixlen 24 ::1 -reject
		;;
	esac
}

network6_static_routes_setup() {
	# Set up any static routes.
        case ${ipv6_defaultrouter} in
        [Nn][Oo] | '')
                ;;
        *)
                ipv6_static_routes="default ${ipv6_static_routes}"
                ipv6_route_default="default ${ipv6_defaultrouter}"
                ;;
        esac
	case ${ipv6_static_routes} in
	[Nn][Oo] | '')
		;;
	*)
		for i in ${ipv6_static_routes}; do
			eval ipv6_route_args=\$ipv6_route_${i}
			route add -inet6 ${ipv6_route_args}
		done
		;;
	esac
}

network6_faith_setup() {
	case ${ipv6_faith_prefix} in
	[Nn][Oo] | '')
		;;
	*)
		sysctl net.inet6.ip6.keepfaith=1
		ifconfig faith0 up
		for prefix in ${ipv6_faith_prefix}; do
			prefixlen=`expr "${prefix}" : ".*/\(.*\)"`
			case ${prefixlen} in
			'')
				prefixlen=96
				;;
			*)
				prefix=`expr "${prefix}" : \
					     "\(.*\)/${prefixlen}"`
				;;
			esac
			route add -inet6 ${prefix} -prefixlen ${prefixlen} ::1
			route change -inet6 ${prefix} -prefixlen ${prefixlen} \
				-ifp faith0
		done
		;;
	esac
}

network6_default_interface_setup() {
	# Choose IPv6 default interface if it is not clearly specified.
	case ${ipv6_default_interface} in
	'')
		for i in ${ipv6_network_interfaces}; do
			case $i in
			lo0|faith[0-9]*)
				continue
				;;
			esac
			laddr=`network6_getladdr $i exclude_tentative`
			case ${laddr} in
			'')
				;;
			*)
				ipv6_default_interface=$i
				break
				;;
			esac
		done
		;;
	esac

	# Disallow unicast packets without outgoing scope identifiers,
	# or route such packets to a "default" interface, if it is specified.
	route add -inet6 fe80:: -prefixlen 10 ::1 -reject
	case ${ipv6_default_interface} in
	[Nn][Oo] | '')
		route add -inet6 ff02:: -prefixlen 16 ::1 -reject
		;;
	*)
		laddr=`network6_getladdr ${ipv6_default_interface}`
		route add -inet6 ff02:: ${laddr} -prefixlen 16 -interface \
			-cloning

		# Disable installing the default interface with the
		# case net.inet6.ip6.forwarding=0 and
		# net.inet6.ip6.accept_rtadv=0, due to avoid conflict
		# between the default router list and the manual
		# configured default route.
		case ${ipv6_gateway_enable} in
		[Yy][Ee][Ss])
			;;
		*)
			if [ `sysctl -n net.inet6.ip6.accept_rtadv` -eq 1 ]
			then
				ndp -I ${ipv6_default_interface}
			fi
			;;
		esac
		;;
	esac
}

network6_getladdr() {
	ifconfig $1 2>/dev/null | while read proto addr rest; do
		case ${proto} in
		inet6)
			case ${addr} in
			fe80::*)
				if [ -z "$2" ]; then
					echo ${addr}
					return
				fi
				case ${rest} in
				*tentative*)
					continue
					;;
				*)
					echo ${addr}
					return
				esac
			esac
		esac
	done
}