#!/bin/sh -
############
# Setup system for IPv6 firewall service.
# $FreeBSD$

# Suck in the configuration variables.
if [ -z "${source_rc_confs_defined}" ]; then
	if [ -r /etc/defaults/rc.conf ]; then
		. /etc/defaults/rc.conf
		source_rc_confs
	elif [ -r /etc/rc.conf ]; then
		. /etc/rc.conf
	fi
fi

############
# Define the firewall type in /etc/rc.conf.  Valid values are:
#   open     - will allow anyone in
#   client   - will try to protect just this machine
#   simple   - will try to protect a whole network
#   closed   - totally disables IP services except via lo0 interface
#   UNKNOWN  - disables the loading of firewall rules.
#   filename - will load the rules in the given filename (full path required)
#
# For ``client'' and ``simple'' the entries below should be customized
# appropriately.

############
#
# If you don't know enough about packet filtering, we suggest that you
# take time to read this book:
#
#	Building Internet Firewalls, 2nd Edition
#	Brent Chapman and Elizabeth Zwicky
#
#	O'Reilly & Associates, Inc
#	ISBN 1-56592-871-7
#	http://www.ora.com/
#	http://www.oreilly.com/catalog/fire2/
#
# For a more advanced treatment of Internet Security read:
#
#	Firewalls and Internet Security: Repelling the Wily Hacker, 2nd Edition
#	William R. Cheswick, Steven M. Bellowin, Aviel D. Rubin
#
#	Addison-Wesley / Prentice Hall
#	ISBN 0-201-63466-X
#	http://www.pearsonhighered.com/
#	http://www.pearsonhighered.com/educator/academic/product/0,3110,020163466X,00.html
#

setup_local () {
	############
	# Only in rare cases do you want to change these rules
	#
	${fw6cmd} add 100 pass ip6 from any to any via lo0
	${fw6cmd} add 200 deny ip6 from any to ::1
	${fw6cmd} add 300 deny ip6 from ::1 to any
	#
	# ND
	#
	# DAD
	${fw6cmd} add pass ip6 from :: to ff02::/16 proto ipv6-icmp
	# RS, RA, NS, NA, redirect...
	${fw6cmd} add pass ip6 from fe80::/10 to fe80::/10 proto ipv6-icmp
	${fw6cmd} add pass ip6 from fe80::/10 to ff02::/16 proto ipv6-icmp
}

if [ -n "${1}" ]; then
	ipv6_firewall_type="${1}"
fi

############
# Set quiet mode if requested
#
case ${ipv6_firewall_quiet} in
[Yy][Ee][Ss])
	fw6cmd="/sbin/ipfw -q"
	;;
*)
	fw6cmd="/sbin/ipfw"
	;;
esac

############
# Flush out the list before we begin.
#
${fw6cmd} -f flush

############
# If you just configured ipfw in the kernel as a tool to solve network
# problems or you just want to disallow some particular kinds of traffic
# then you will want to change the default policy to open.  You can also
# do this as your only action by setting the ipv6_firewall_type to ``open''.
#
# ${fw6cmd} add 65000 pass all from any to any


# Prototype setups.
#
case ${ipv6_firewall_type} in
[Oo][Pp][Ee][Nn])
	setup_local
	${fw6cmd} add 65000 pass ip6 from any to any
	;;

[Cc][Ll][Ii][Ee][Nn][Tt])
	############
	# This is a prototype setup that will protect your system somewhat
	# against people from outside your own network.
	############

	# set these to your network and prefixlen and ip
	#
	# This needs more work
	#
	net="2001:db8:2:1::"
	prefixlen="64"
	ip="2001:db8:2:1::1"

	setup_local

	# Allow any traffic to or from my own net.
	${fw6cmd} add pass ip6 from ${ip} to ${net}/${prefixlen}
	${fw6cmd} add pass ip6 from ${net}/${prefixlen} to ${ip}

	# Allow any link-local multicast traffic
	${fw6cmd} add pass ip6 from fe80::/10 to ff02::/16
	${fw6cmd} add pass ip6 from ${net}/${prefixlen} to ff02::/16

	# Allow TCP through if setup succeeded
	${fw6cmd} add pass ip6 from any to any established proto tcp

	# Allow IP fragments to pass through
	${fw6cmd} add pass ip6 from any to any frag

	# Allow setup of incoming email
	${fw6cmd} add pass ip6 from any to ${ip} 25 setup proto tcp

	# Allow setup of outgoing TCP connections only
	${fw6cmd} add pass ip6 from ${ip} to any setup proto tcp

	# Disallow setup of all other TCP connections
	${fw6cmd} add deny ip6 from any to any setup proto tcp

	# Allow DNS queries out in the world
	${fw6cmd} add pass ip6 from any 53 to ${ip} proto udp
	${fw6cmd} add pass ip6 from ${ip} to any 53 proto udp

	# Allow NTP queries out in the world
	${fw6cmd} add pass ip6 from any 123 to ${ip} proto udp
	${fw6cmd} add pass ip6 from ${ip} to any 123 proto udp

	# Allow ICMPv6 destination unreach
	${fw6cmd} add pass ip6 from any to any icmp6types 1 proto ipv6-icmp

	# Allow NS/NA/toobig (don't filter it out)
	${fw6cmd} add pass ip6 from any to any icmp6types 2,135,136 \
	    proto ipv6-icmp

	# Everything else is denied by default, unless the
	# IPV6FIREWALL_DEFAULT_TO_ACCEPT option is set in your kernel
	# config file.
	;;

[Ss][Ii][Mm][Pp][Ll][Ee])
	############
	# This is a prototype setup for a simple firewall.  Configure this
	# machine as a DNS and NTP server, and point all the machines
	# on the inside at this machine for those services.
	############

	# set these to your outside interface network and prefixlen and ip
	oif="ed0"
	onet="2001:db8:2:1::"
	oprefixlen="64"
	oip="2001:db8:2:1::1"

	# set these to your inside interface network and prefixlen and ip
	iif="ed1"
	inet="2001:db8:2:2::"
	iprefixlen="64"
	iip="2001:db8:2:2::1"

	setup_local

	# Stop spoofing
	${fw6cmd} add deny ip6 from ${inet}/${iprefixlen} to any in via ${oif}
	${fw6cmd} add deny ip6 from ${onet}/${oprefixlen} to any in via ${iif}

	# Stop unique local unicast address on the outside interface
	${fw6cmd} add deny ip6 from fc00::/7 to any via ${oif}
	${fw6cmd} add deny ip6 from any to fc00::/7 via ${oif}

	# Stop site-local on the outside interface
	${fw6cmd} add deny ip6 from fec0::/10 to any via ${oif}
	${fw6cmd} add deny ip6 from any to fec0::/10 via ${oif}

	# Disallow "internal" addresses to appear on the wire.
	${fw6cmd} add deny ip6 from ::ffff:0.0.0.0/96 to any via ${oif}
	${fw6cmd} add deny ip6 from any to ::ffff:0.0.0.0/96 via ${oif}

	# Disallow packets to malicious IPv4 compatible prefix.
	${fw6cmd} add deny ip6 from ::224.0.0.0/100 to any via ${oif}
	${fw6cmd} add deny ip6 from any to ::224.0.0.0/100 via ${oif}
	${fw6cmd} add deny ip6 from ::127.0.0.0/104 to any via ${oif}
	${fw6cmd} add deny ip6 from any to ::127.0.0.0/104 via ${oif}
	${fw6cmd} add deny ip6 from ::0.0.0.0/104 to any via ${oif}
	${fw6cmd} add deny ip6 from any to ::0.0.0.0/104 via ${oif}
	${fw6cmd} add deny ip6 from ::255.0.0.0/104 to any via ${oif}
	${fw6cmd} add deny ip6 from any to ::255.0.0.0/104 via ${oif}

	${fw6cmd} add deny ip6 from ::0.0.0.0/96 to any via ${oif}
	${fw6cmd} add deny ip6 from any to ::0.0.0.0/96 via ${oif}

	# Disallow packets to malicious 6to4 prefix.
	${fw6cmd} add deny ip6 from 2002:e000::/20 to any via ${oif}
	${fw6cmd} add deny ip6 from any to 2002:e000::/20 via ${oif}
	${fw6cmd} add deny ip6 from 2002:7f00::/24 to any via ${oif}
	${fw6cmd} add deny ip6 from any to 2002:7f00::/24 via ${oif}
	${fw6cmd} add deny ip6 from 2002:0000::/24 to any via ${oif}
	${fw6cmd} add deny ip6 from any to 2002:0000::/24 via ${oif}
	${fw6cmd} add deny ip6 from 2002:ff00::/24 to any via ${oif}
	${fw6cmd} add deny ip6 from any to 2002:ff00::/24 via ${oif}

	${fw6cmd} add deny ip6 from 2002:0a00::/24 to any via ${oif}
	${fw6cmd} add deny ip6 from any to 2002:0a00::/24 via ${oif}
	${fw6cmd} add deny ip6 from 2002:ac10::/28 to any via ${oif}
	${fw6cmd} add deny ip6 from any to 2002:ac10::/28 via ${oif}
	${fw6cmd} add deny ip6 from 2002:c0a8::/32 to any via ${oif}
	${fw6cmd} add deny ip6 from any to 2002:c0a8::/32 via ${oif}

	${fw6cmd} add deny ip6 from ff05::/16 to any via ${oif}
	${fw6cmd} add deny ip6 from any to ff05::/16 via ${oif}

	# Allow TCP through if setup succeeded
	${fw6cmd} add pass tcp from any to any established

	# Allow IP fragments to pass through
	${fw6cmd} add pass ip6 from any to any frag

	# Allow setup of incoming email
	${fw6cmd} add pass ip6 from any to ${oip} 25 setup proto tcp

	# Allow access to our DNS
	${fw6cmd} add pass ip6 from any to ${oip} 53 setup proto tcp
	${fw6cmd} add pass ip6 from any to ${oip} 53 proto udp
	${fw6cmd} add pass ip6 from ${oip} 53 to any proto udp

	# Allow access to our WWW
	${fw6cmd} add pass ip6 from any to ${oip} 80 setup proto tcp

	# Reject&Log all setup of incoming connections from the outside
	${fw6cmd} add deny log ip6 from any to any in via ${oif} setup \
	    proto tcp

	# Allow setup of any other TCP connection
	${fw6cmd} add pass ip6 from any to any setup proto tcp

	# Allow DNS queries out in the world
	${fw6cmd} add pass ip6 from any 53 to ${oip} proto udp
	${fw6cmd} add pass ip6 from ${oip} to any 53 proto udp

	# Allow NTP queries out in the world
	${fw6cmd} add pass ip6 from any 123 to ${oip} proto udp
	${fw6cmd} add pass ip6 from ${oip} to any 123 proto udp

	# Allow RIPng
	#${fw6cmd} add pass ip6 from fe80::/10 521 to ff02::9 521 proto udp
	#${fw6cmd} add pass ip6 from fe80::/10 521 to fe80::/10 521 proto udp

	# Allow ICMPv6 destination unreach
	${fw6cmd} add pass ip6 from any to any icmp6types 1 proto ipv6-icmp

	# Allow NS/NA/toobig (don't filter it out)
	${fw6cmd} add pass ip6 from any to any icmp6types 2,135,136 \
	     proto ipv6-icmp

	# Everything else is denied by default, unless the
	# IPV6FIREWALL_DEFAULT_TO_ACCEPT option is set in your kernel
	# config file.
	;;

[Cc][Ll][Oo][Ss][Ee][Dd])
	# Only enable the loopback interface
	${fw6cmd} add 100 pass ip6 from any to any via lo0
	;;
[Uu][Nn][Kk][Nn][Oo][Ww][Nn])
	;;
*)
	if [ -r "${ipv6_firewall_type}" ]; then
		${fw6cmd} ${ipv6_firewall_flags} ${ipv6_firewall_type}
	fi
	;;
esac