rc.firewall revision 64028
1############
2# Setup system for firewall service.
3# $FreeBSD: head/etc/rc.firewall 64028 2000-07-30 19:28:05Z obrien $
4
5# Suck in the configuration variables.
6if [ -r /etc/defaults/rc.conf ]; then
7	. /etc/defaults/rc.conf
8	source_rc_confs
9elif [ -r /etc/rc.conf ]; then
10	. /etc/rc.conf
11fi
12
13############
14# Define the firewall type in /etc/rc.conf.  Valid values are:
15#   open     - will allow anyone in
16#   client   - will try to protect just this machine
17#   simple   - will try to protect a whole network
18#   closed   - totally disables IP services except via lo0 interface
19#   UNKNOWN  - disables the loading of firewall rules.
20#   filename - will load the rules in the given filename (full path required)
21#
22# For ``client'' and ``simple'' the entries below should be customized
23# appropriately.
24
25############
26#
27# If you don't know enough about packet filtering, we suggest that you
28# take time to read this book:
29#
30#	Building Internet Firewalls
31#	Brent Chapman and Elizabeth Zwicky
32#
33#	O'Reilly & Associates, Inc
34#	ISBN 1-56592-124-0
35#	http://www.ora.com/
36#
37# For a more advanced treatment of Internet Security read:
38#
39#	Firewalls & Internet Security
40#	Repelling the wily hacker
41#	William R. Cheswick, Steven M. Bellowin
42#
43#	Addison-Wesley
44#	ISBN 0-201-6337-4
45#	http://www.awl.com/
46#
47
48if [ -n "${1}" ]; then
49	firewall_type="${1}"
50fi
51
52############
53# Set quiet mode if requested
54#
55case ${firewall_quiet} in
56[Yy][Ee][Ss])
57	fwcmd="/sbin/ipfw -q"
58	;;
59*)
60	fwcmd="/sbin/ipfw"
61	;;
62esac
63
64############
65# Flush out the list before we begin.
66#
67${fwcmd} -f flush
68
69############
70# These rules are required for using natd.  All packets are passed to
71# natd before they encounter your remaining rules.  The firewall rules
72# will then be run again on each packet after translation by natd,
73# minus any divert rules (see natd(8)).
74#
75case ${natd_enable} in
76[Yy][Ee][Ss])
77	if [ -n "${natd_interface}" ]; then
78	      ${fwcmd} add 50 divert natd all from any to any via ${natd_interface}
79	fi
80	;;
81esac
82
83############
84# If you just configured ipfw in the kernel as a tool to solve network
85# problems or you just want to disallow some particular kinds of traffic
86# then you will want to change the default policy to open.  You can also
87# do this as your only action by setting the firewall_type to ``open''.
88#
89# ${fwcmd} add 65000 pass all from any to any
90
91############
92# Only in rare cases do you want to change these rules
93#
94${fwcmd} add 100 pass all from any to any via lo0
95${fwcmd} add 200 deny all from any to 127.0.0.0/8
96# If you're using 'options BRIDGE', uncomment the following line to pass ARP
97#${fwcmd} add 300 pass udp from 0.0.0.0 2054 to 0.0.0.0
98
99
100# Prototype setups.
101#
102case ${firewall_type} in
103[Oo][Pp][Ee][Nn])
104	${fwcmd} add 65000 pass all from any to any
105	;;
106
107[Cc][Ll][Ii][Ee][Nn][Tt])
108	############
109	# This is a prototype setup that will protect your system somewhat
110	# against people from outside your own network.
111	############
112
113	# set these to your network and netmask and ip
114	net="192.0.2.0"
115	mask="255.255.255.0"
116	ip="192.0.2.1"
117
118	# Allow any traffic to or from my own net.
119	${fwcmd} add pass all from ${ip} to ${net}:${mask}
120	${fwcmd} add pass all from ${net}:${mask} to ${ip}
121
122	# Allow TCP through if setup succeeded
123	${fwcmd} add pass tcp from any to any established
124
125	# Allow IP fragments to pass through
126	${fwcmd} add pass all from any to any frag
127
128	# Allow setup of incoming email
129	${fwcmd} add pass tcp from any to ${ip} 25 setup
130
131	# Allow setup of outgoing TCP connections only
132	${fwcmd} add pass tcp from ${ip} to any setup
133
134	# Disallow setup of all other TCP connections
135	${fwcmd} add deny tcp from any to any setup
136
137	# Allow DNS queries out in the world
138	${fwcmd} add pass udp from any 53 to ${ip}
139	${fwcmd} add pass udp from ${ip} to any 53
140
141	# Allow NTP queries out in the world
142	${fwcmd} add pass udp from any 123 to ${ip}
143	${fwcmd} add pass udp from ${ip} to any 123
144
145	# Everything else is denied by default, unless the
146	# IPFIREWALL_DEFAULT_TO_ACCEPT option is set in your kernel
147	# config file.
148	;;
149
150[Ss][Ii][Mm][Pp][Ll][Ee])
151	############
152	# This is a prototype setup for a simple firewall.  Configure this
153	# machine as a named server and ntp server, and point all the machines
154	# on the inside at this machine for those services.
155	############
156
157	# set these to your outside interface network and netmask and ip
158	oif="ed0"
159	onet="192.0.2.0"
160	omask="255.255.255.240"
161	oip="192.0.2.1"
162
163	# set these to your inside interface network and netmask and ip
164	iif="ed1"
165	inet="192.0.2.16"
166	imask="255.255.255.240"
167	iip="192.0.2.17"
168
169	# Stop spoofing
170	${fwcmd} add deny all from ${inet}:${imask} to any in via ${oif}
171	${fwcmd} add deny all from ${onet}:${omask} to any in via ${iif}
172
173	# Stop RFC1918 nets on the outside interface
174	${fwcmd} add deny all from 10.0.0.0/8 to any via ${oif}
175	${fwcmd} add deny all from any to 10.0.0.0/8 via ${oif}
176	${fwcmd} add deny all from 172.16.0.0/12 to any via ${oif}
177	${fwcmd} add deny all from any to 172.16.0.0/12 via ${oif}
178	${fwcmd} add deny all from 192.168.0.0/16 to any via ${oif}
179	${fwcmd} add deny all from any to 192.168.0.0/16 via ${oif}
180
181	# Stop draft-manning-dsua-03.txt (1 May 2000) nets (includes RESERVED-1,
182	# DHCP auto-configuration, NET-TEST, MULTICAST (class D), and class E)
183	# on the outside interface
184	${fwcmd} add deny all from 0.0.0.0/8 to any via ${oif}
185	${fwcmd} add deny all from any to 0.0.0.0/8 via ${oif}
186	${fwcmd} add deny all from 169.254.0.0/16 to any via ${oif}
187	${fwcmd} add deny all from any to 169.254.0.0/16 via ${oif}
188	${fwcmd} add deny all from 192.0.2.0/24 to any via ${oif}
189	${fwcmd} add deny all from any to 192.0.2.0/24 via ${oif}
190	${fwcmd} add deny all from 224.0.0.0/4 to any via ${oif}
191	${fwcmd} add deny all from any to 224.0.0.0/4 via ${oif}
192	${fwcmd} add deny all from 240.0.0.0/4 to any via ${oif}
193	${fwcmd} add deny all from any to 240.0.0.0/4 via ${oif}
194
195	# Allow TCP through if setup succeeded
196	${fwcmd} add pass tcp from any to any established
197
198	# Allow IP fragments to pass through
199	${fwcmd} add pass all from any to any frag
200
201	# Allow setup of incoming email
202	${fwcmd} add pass tcp from any to ${oip} 25 setup
203
204	# Allow access to our DNS
205	${fwcmd} add pass tcp from any to ${oip} 53 setup
206	${fwcmd} add pass udp from any to ${oip} 53
207	${fwcmd} add pass udp from ${oip} 53 to any
208
209	# Allow access to our WWW
210	${fwcmd} add pass tcp from any to ${oip} 80 setup
211
212	# Reject&Log all setup of incoming connections from the outside
213	${fwcmd} add deny log tcp from any to any in via ${oif} setup
214
215	# Allow setup of any other TCP connection
216	${fwcmd} add pass tcp from any to any setup
217
218	# Allow DNS queries out in the world
219	${fwcmd} add pass udp from any 53 to ${oip}
220	${fwcmd} add pass udp from ${oip} to any 53
221
222	# Allow NTP queries out in the world
223	${fwcmd} add pass udp from any 123 to ${oip}
224	${fwcmd} add pass udp from ${oip} to any 123
225
226	# Everything else is denied by default, unless the
227	# IPFIREWALL_DEFAULT_TO_ACCEPT option is set in your kernel
228	# config file.
229	;;
230
231[Uu][Nn][Kk][Nn][Oo][Ww][Nn])
232	;;
233*)
234	if [ -r "${firewall_type}" ]; then
235		${fwcmd} ${firewall_flags} ${firewall_type}
236	fi
237	;;
238esac
239