# $FreeBSD: head/share/examples/ipfilter/ipf.conf.restrictive 85213 2001-10-20 04:17:07Z darrenr $
#--------------------------------------------------------------------------
# ed1 - external interface
# fxp0 - internal interface
#--------------------------------------------------------------------------
# First, nasty packets which we don't want near us at all
# packets which are too short to be real except echo replies on lo0
pass in log quick on lo0 proto icmp from 127.0.0.1/8 to 127.0.0.1/8 with short
block in log quick all with short
block in log quick all with opt lsrr
block in log quick all with opt ssrr
#--------------------------------------------------------------------------
# loopback packets left unmolested
pass in log quick on lo0 all
pass out log quick on lo0 all
#--------------------------------------------------------------------------
# Group setup:
# 100 incoming ed1
# 150 outgoing ed1
# 200 incoming fxp0
# 250 outgoing fxp0
#--------------------------------------------------------------------------
block in log body on ed1 all head 100
block out log body on ed1 all head 150
#--------------------------------------------------------------------------
block in log on fxp0 all head 200
block out log on fxp0 all head 250
#--------------------------------------------------------------------------
# incoming ed1 traffic - group 100
# 1) prevent localhost spoofing
block in log quick from 127.0.0.1/32 to 192.168.0.0/24 group 100
block in log quick from 127.0.0.1/32 to 192.168.1.0/24 group 100
block in log quick from any to 127.0.0.1/8 group 100
#--------------------------------------------------------------------------
# 2) deny pakets which should not be seen on th internet (paranoid)
block in log quick from 10.0.0.0/8 to any group 100
block in log quick from any to 10.0.0.0/8 group 100
block in log quick from 172.16.0.0/16 to any group 100
block in log quick from any to 172.16.0.0/16 group 100
block in log quick from 192.168.0.0/16 to any group 100
block in log from any to 192.168.0.0/16 group 100
# 3) implement policy
# allow incoming ftp-data
pass in log quick proto tcp/udp from any to 192.168.1.1/24 keep state group 100
# if nothing applies, block and return icmp-replies (unreachable and rst)
block return-icmp(net-unr) in proto udp from any to any group 100
block return-rst in log proto tcp from any to any group 100
#--------------------------------------------------------------------------
# outgoing ed1 traffic - group 150
# Setup outgoing DNS
pass out log quick proto tcp/udp from any to 212.40.0.10 port = 53 keep state group 150
pass out log quick proto tcp/udp from any to 212.40.5.50 port = 53 keep state group 150
# allow outgoing http-service
pass out log quick proto tcp from any to any port = 80 flags S/SA keep state keep frags group 150
# allow outgoing smtp traffic
pass out log quick proto tcp from 192.168.1.1/24 to any port = 25 flags S/SA keep state group 150
# allow outgoing pop3 traffic
pass out log quick proto tcp from 192.168.1.1/24 to any port = 110 flags S/SA keep state group 150
# allow outgoing ftp traffic
pass out log quick proto tcp/udp from 192.168.1.1/24 to any port = ftp keep state group 150
pass out log quick proto icmp from any to any keep state keep frags group 150
#--------------------------------------------------------------------------
# incoming traffic on fxp0 - group 200
#--------------------------------------------------------------------------
# 1) prevent localhost spoofing
block in log quick from 127.0.0.0/8 to any group 200
block in log quick from 192.168.0.1/32 to any group 200
block in log quick from 192.168.1.110/24 to any group 200
pass in log quick from any to any group 200
#--------------------------------------------------------------------------
# outgoing traffic on fxp0 - group 250
#--------------------------------------------------------------------------
block out log quick from 127.0.0.0/8 to any group 250
block out quick from any to 127.0.0.0/8 group 250
block out log quick from any to 192.168.0.1/32 group 250
pass out log quick from any to nay group 250
#--------------------------------------------------------------------------