#!/bin/sh -

# set these to your outside interface network and netmask and ip
oif="tun0"
#	onet="x.x.x.x"
#	omask="255.255.255.0"
#	oip="x.x.x.x"

# set these to your inside interface network and netmask and ip
iif="fxp0"
inet="10.0.0.0"
imask="255.255.255.0"
iip="10.0.0.1"

# inetd mailserver
inetdmail="211.13.206.142"


# Setup system for firewall service.
#

# 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

setup_loopback () {
	############
	# Only in rare cases do you want to change these rules
	#
	${fwcmd} add 100 pass all from any to any via lo0
	${fwcmd} add 200 deny all from any to 127.0.0.0/8
	${fwcmd} add 300 deny ip from 127.0.0.0/8 to any
}

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

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

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

	############
	# This is a prototype setup for a simple firewall.  Configure this
	# machine as a named server and ntp server, and point all the machines
	# on the inside at this machine for those services.
	############


	setup_loopback

	# Stop spoofing
#	${fwcmd} add deny all from ${inet}:${imask} to any in via ${oif}
#	${fwcmd} add deny all from ${onet}:${omask} to any in via ${iif}

	# Stop RFC1918 nets on the outside interface
	${fwcmd} add deny all from any to 10.0.0.0/8 via ${oif}
	${fwcmd} add deny all from any to 172.16.0.0/12 via ${oif}
	${fwcmd} add deny all from any to 192.168.0.0/16 via ${oif}

	# Stop draft-manning-dsua-03.txt (1 May 2000) nets (includes RESERVED-1,
	# DHCP auto-configuration, NET-TEST, MULTICAST (class D), and class E)
	# on the outside interface
	${fwcmd} add deny all from any to 0.0.0.0/8 via ${oif}
	${fwcmd} add deny all from any to 169.254.0.0/16 via ${oif}
	${fwcmd} add deny all from any to 192.0.2.0/24 via ${oif}
	${fwcmd} add deny all from any to 224.0.0.0/4 via ${oif}
	${fwcmd} add deny all from any to 240.0.0.0/4 via ${oif}

	# NetBIOS
	${fwcmd} add deny log udp from any to any 137-139,135,445 via tun0
	${fwcmd} add deny log udp from any 137-139,135,445 to any via tun0
	${fwcmd} add deny log tcp from any to any 137-139,135,445 via tun0
	${fwcmd} add deny log tcp from any 137-139,135,445 to any via tun0

	# Network Address Translation.  This rule is placed here deliberately
	# so that it does not interfere with the surrounding address-checking
	# rules.  If for example one of your internal LAN machines had its IP
	# address set to 192.0.2.1 then an incoming packet for it after being
	# translated by natd(8) would match the `deny' rule above.  Similarly
	# an outgoing packet originated from it before being translated would
	# match the `deny' rule below.
	case ${natd_enable} in
	[Yy][Ee][Ss])
		if [ -n "${natd_interface}" ]; then
			${fwcmd} add divert natd all from any to any via ${natd_interface}
		fi
		;;
	esac

	# Stop RFC1918 nets on the outside interface
	${fwcmd} add deny all from 10.0.0.0/8 to any via ${oif}
	${fwcmd} add deny all from 172.16.0.0/12 to any via ${oif}
	${fwcmd} add deny all from 192.168.0.0/16 to any via ${oif}

	# Stop draft-manning-dsua-03.txt (1 May 2000) nets (includes RESERVED-1,
	# DHCP auto-configuration, NET-TEST, MULTICAST (class D), and class E)
	# on the outside interface
	${fwcmd} add deny all from 0.0.0.0/8 to any via ${oif}
	${fwcmd} add deny all from 169.254.0.0/16 to any via ${oif}
	${fwcmd} add deny all from 192.0.2.0/24 to any via ${oif}
	${fwcmd} add deny all from 224.0.0.0/4 to any via ${oif}
	${fwcmd} add deny all from 240.0.0.0/4 to any via ${oif}

	# Reject SMTP from local network except toriyu.dd.que.ne.jp and inetdmail
	${fwcmd} add allow tcp from ${iip} to any 25 setup
	${fwcmd} add allow tcp from any to ${inetdmail} 25 setup
	${fwcmd} add allow tcp from ${inet}:${imask} to ${iip} 25 setup
	${fwcmd} add deny log tcp from ${inet}:${imask} to any 25 setup

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

	# Allow IP fragments to pass through
	${fwcmd} add pass all from any to any frag

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

	# Allow setup of incoming POP3
#	${fwcmd} add pass tcp from any to ${oip} 110 setup


	# CHECK STATE
	${fwcmd} add check-state

	${fwcmd} add allow tcp from any to any keep-state out via ${oif}
	${fwcmd} add allow udp from any to any keep-state out via ${oif}
	${fwcmd} add allow tcp from ${inet}:$imask to any keep-state
	${fwcmd} add allow udp from ${inet}:$imask to any keep-state

	# ftp
#	${fwcmd} add allow tcp from any 20 to ${inet}:${imask} 1024-65535 setup in via ${oif}


	# Reject&Log all setup of incoming connections from the outside
	${fwcmd} add 30000 deny log tcp from any to any in via ${oif} setup

	# Allow setup of any other TCP connection
	${fwcmd} add pass tcp from any to any via ${oif} setup

	# allow ICMP
	${fwcmd} add allow icmp from any to any in via ${oif} icmptype 0,3,4,11,12
	${fwcmd} add allow icmp from any to any out via ${oif} icmptype 0,3,4,8,11,12
	${fwcmd} add allow icmp from any to any via ${iif} icmptype 0,3,4,8,11,12
#	${fwcmd} add deny icmp from any to any via ${oif}

#	${fwcmd} add 65000 deny log tcp from any to any
#	${fwcmd} add 65100 deny log udp from any to any

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