xref: /dragonfly/share/examples/pf/faq-example1 (revision 0fe46dc6) 
1# $OpenBSD: faq-example1,v 1.3 2005/07/02 16:16:39 joel Exp $
2# $DragonFly: src/share/examples/pf/faq-example1,v 1.1 2005/12/13 01:58:27 corecode Exp $
3
4#
5# Firewall for Home or Small Office
6# http://www.openbsd.org/faq/pf/example1.html
7#
8
9
10# macros
11int_if = "fxp0"
12ext_if = "ep0"
13
14tcp_services = "{ 22, 113 }"
15icmp_types = "echoreq"
16
17priv_nets = "{ 127.0.0.0/8, 192.168.0.0/16, 172.16.0.0/12, 10.0.0.0/8 }"
18
19comp3 = "192.168.0.3"
20
21# options
22set block-policy return
23set loginterface $ext_if
24
25# scrub
26scrub in all
27
28# nat/rdr
29nat on $ext_if from $int_if:network to any -> ($ext_if)
30rdr on $int_if proto tcp from any to any port 21 -> 127.0.0.1 \
31   port 8021
32rdr on $ext_if proto tcp from any to any port 80 -> $comp3
33
34# filter rules
35block all
36
37pass quick on lo0 all
38
39block drop in  quick on $ext_if from $priv_nets to any
40block drop out quick on $ext_if from any to $priv_nets
41
42pass in on $ext_if inet proto tcp from any to ($ext_if) \
43   port $tcp_services flags S/SA keep state
44
45pass in on $ext_if proto tcp from any to $comp3 port 80 \
46   flags S/SA synproxy state
47
48pass in on $ext_if inet proto tcp from port 20 to ($ext_if) \
49   user proxy flags S/SA keep state
50
51pass in inet proto icmp all icmp-type $icmp_types keep state
52
53pass in  on $int_if from $int_if:network to any keep state
54pass out on $int_if from any to $int_if:network keep state
55
56pass out on $ext_if proto tcp all modulate state flags S/SA
57pass out on $ext_if proto { udp, icmp } all keep state
58