3 ### Local firewall configuration
5 ### (c) 2008 Mark Wooding
8 ###----- Licensing notice ---------------------------------------------------
10 ### This program is free software; you can redistribute it and/or modify
11 ### it under the terms of the GNU General Public License as published by
12 ### the Free Software Foundation; either version 2 of the License, or
13 ### (at your option) any later version.
15 ### This program is distributed in the hope that it will be useful,
16 ### but WITHOUT ANY WARRANTY; without even the implied warranty of
17 ### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 ### GNU General Public License for more details.
20 ### You should have received a copy of the GNU General Public License
21 ### along with this program; if not, write to the Free Software Foundation,
22 ### Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
24 ###--------------------------------------------------------------------------
25 ### Local configuration.
28 ## Default NTP servers.
30 "81.187.26.174 90.155.23.205 2001:8b0:0:23::205 185.73.44.6 2001:ba8:0:2c06::")
33 ###--------------------------------------------------------------------------
34 ### Packet classification.
38 ## There are two small blocks of publicly routable IPv4 addresses, and a
39 ## block of RFC1918 private-use addresses allocated from the Cambridge G-RIN.
40 ## The former are as follows.
42 ## 81.2.113.195, 81.187.238.128/28, 217.169.12.64/28
43 ## House border network (dmz). We have all of these; the loose
44 ## address is for the router.
46 ## The latter is the block 172.29.196.0/22. Currently the low half is
47 ## unallocated (and may be returned to the G-RIN); the remaining addresses
48 ## are allocated as follows.
50 ## 172.29.198.0/24 Untrusted networks.
51 ## .0/25 house wireless net
52 ## .128/28 iodine (IP-over-DNS) network
53 ## .144/28 hippotat (IP-over-HTTP) network
54 ## .160/27 untrusted virtual network
56 ## 172.29.199.0/24 Trusted networks.
57 ## .0/25 house wired network
58 ## .128/27 mobile VPN hosts
59 ## .160/28 reserved, except .160/30 allocated for ITS
60 ## .176/28 internal colocated network
61 ## .192/27 house safe network
62 ## .224/27 anycast services
66 ## There are five blocks of publicly routable IPv6 addresses, though some of
67 ## them aren't very interesting. The ranges are as follows.
70 ## Main house range (aaisp). See below for allocation policy.
71 ## There is no explicit DMZ allocation (and no need for one).
73 ## Addresses in the /64 networks are simply allocated in ascending order.
74 ## The /48s are split into /64s by appending a 16-bit network number. The
75 ## top nibble of the network number classifies the network, as follows.
77 ## axxx Virtual, untrusted
81 ## 0xxx Unsafe, trusted
83 ## These have been chosen so that network properties can be deduced by
84 ## inspecting bits of the network number:
86 ## Bit 15 If set, the network is untrusted; otherwise it is trusted.
87 ## Bit 14 If set, the network is safe; otherwise it is unsafe.
89 ## Finally, the low-order nibbles identify the site.
91 ## 0 No specific site: mobile VPN endpoints or anycast addresses.
93 ## fff Local border network.
95 ## Define the available network classes.
97 defnetclass scary scary trusted vpnnat mcast
98 defnetclass untrusted scary untrusted trusted mcast
99 defnetclass trusted scary untrusted trusted safe noloop vpnnat mcast
100 defnetclass safe trusted safe noloop vpnnat mcast
101 defnetclass noloop trusted safe mcast
102 defnetclass vpnnat scary trusted safe mcast
109 ###--------------------------------------------------------------------------
114 addr 81.2.113.195 81.187.238.128/28 217.169.12.64/28 2001:8b0:c92:fff::/64
116 defnet unsafe trusted
117 addr 172.29.199.0/25 2001:8b0:c92:1::/64
120 addr 172.29.199.192/27 2001:8b0:c92:4001::/64
122 defnet untrusted untrusted
123 addr 172.29.198.0/25 2001:8b0:c92:8001::/64
126 defnet househub virtual
127 via housebdry dmz unsafe safe untrusted
128 defnet housebdry virtual
134 iface eth0 dmz unsafe safe untrusted vpn sgo default
135 iface eth1 dmz unsafe safe untrusted vpn sgo default
136 iface eth2 dmz unsafe safe untrusted vpn sgo
137 iface eth3 unsafe untrusted vpn default
140 iface vpn-precision vpn sgo
144 iface eth0 dmz unsafe
145 iface eth1 dmz unsafe
147 iface eth0 dmz unsafe
148 iface eth1 dmz unsafe
150 iface eth0 dmz unsafe
151 iface eth1 dmz unsafe
154 iface eth0 dmz unsafe untrusted
155 iface eth1 dmz unsafe untrusted
156 iface eth3 unsafe untrusted
159 iface eth0.4 dmz unsafe untrusted safe vpn sgo
160 iface eth0.5 dmz unsafe untrusted safe vpn sgo
161 iface eth0.6 dmz unsafe safe untrusted vpn sgo
162 iface eth0.7 unsafe untrusted vpn
163 iface vpn-precision vpn sgo
167 iface br-dmz dmz unsafe
168 iface br-unsafe unsafe
170 iface wlan0 untrusted
171 iface vpn-radius unsafe
174 iface wlan0 untrusted
175 iface vpn-radius unsafe
181 ## Formerly colocated hosts.
183 iface br-dmz dmz unsafe
184 iface br-unsafe dmz unsafe
187 iface eth0 dmz unsafe vpn sgo
188 iface eth1 dmz unsafe vpn sgo
189 iface vpn-mango binswood
191 iface vpn-national upn
195 iface eth0 dmz unsafe vpn sgo
196 iface eth1 dmz unsafe vpn sgo
198 iface eth0 dmz unsafe vpn sgo
199 iface eth1 dmz unsafe vpn sgo
202 iface eth0 dmz unsafe vpn sgo
203 iface eth1 dmz unsafe vpn sgo
205 iface hippo-svc hippotat
208 ## Stunt connectivity networks.
209 defnet iodine untrusted
210 addr 172.29.198.128/28
212 defnet hippotat untrusted
213 addr 172.29.198.144/28
221 addr !172.29.198.0/23
228 addr 172.29.199.128/27 2001:8b0:c92:6000::/64
235 host groove 10 ::10:1
236 defnet anycast trusted
237 addr 172.29.199.224/27 2001:8b0:c92:0::/64
238 via dmz unsafe safe untrusted vpn nvpn
240 addr 81.2.113.195 81.187.238.128/28 217.169.12.64/28 \
242 via dmz unsafe untrusted
244 addr 172.29.198.160/27 2001:8b0:c92:a000::/64
246 host national 1 ::1:1
252 iface vpn-precision househub
254 ## Satellite networks.
255 defnet binswood vpnnat
260 iface eth0 binswood default
261 iface vpn-precision dmz default
264 ###--------------------------------------------------------------------------
265 ### Connection tracking helper modules.
268 modprobe nf_conntrack_$i
272 ###--------------------------------------------------------------------------
273 ### Special forwarding exemptions.
278 ## Only allow these packets if they're not fragmented. (Don't trust safe
279 ## hosts's fragment reassembly to be robust against malicious fragments.)
280 ## There's a hideous bug in iptables 1.4.11.1 which botches the meaning
281 ## of `! -f', so we do the negation using early return from a subchain.
282 clearchain fwd-spec-nofrag
283 run iptables -A fwd-spec-nofrag -j RETURN --fragment
284 run ip6tables -A fwd-spec-nofrag -j RETURN \
285 -m ipv6header --soft --header frag
286 run ip46tables -A FORWARD -j fwd-spec-nofrag
288 ## Allow ping from safe/noloop to untrusted networks.
289 run iptables -A fwd-spec-nofrag -j ACCEPT \
290 -p icmp --icmp-type echo-request \
291 -m mark --mark $to_untrusted/$MASK_TO
292 run iptables -A fwd-spec-nofrag -j ACCEPT \
293 -p icmp --icmp-type echo-reply \
294 -m mark --mark $from_untrusted/$MASK_FROM \
295 -m state --state ESTABLISHED
296 run ip6tables -A fwd-spec-nofrag -j ACCEPT \
297 -p icmpv6 --icmpv6-type echo-request \
298 -m mark --mark $to_untrusted/$MASK_TO
299 run ip6tables -A fwd-spec-nofrag -j ACCEPT \
300 -p icmpv6 --icmpv6-type echo-reply \
301 -m mark --mark $from_untrusted/$MASK_FROM \
302 -m state --state ESTABLISHED
304 ## Allow SSH from safe/noloop to untrusted networks.
305 run ip46tables -A fwd-spec-nofrag -j ACCEPT \
306 -p tcp --destination-port $port_ssh \
307 -m mark --mark $to_untrusted/$MASK_TO
308 run ip46tables -A fwd-spec-nofrag -j ACCEPT \
309 -p tcp --source-port $port_ssh \
310 -m mark --mark $from_untrusted/$MASK_FROM \
311 -m state --state ESTABLISHED
317 ###--------------------------------------------------------------------------
318 ### Kill things we don't understand properly.
320 ### I don't like having to do this, but since I don't know how to do proper
321 ### multicast filtering, I'm just going to ban it from being forwarded.
323 errorchain poorly-understood REJECT
325 ## Ban multicast destination addresses in forwarding.
328 run iptables -A FORWARD -g poorly-understood \
330 run ip6tables -A FORWARD -g poorly-understood \
336 ###--------------------------------------------------------------------------
337 ### Check for source routing.
339 clearchain check-srcroute
341 run iptables -A check-srcroute -g forbidden \
342 -m ipv4options --any --flags lsrr,ssrr
343 run ip6tables -A check-srcroute -g forbidden \
346 for c in INPUT FORWARD; do
347 for m in $from_scary $from_untrusted; do
348 run ip46tables -A $c -m mark --mark $m/$MASK_FROM -j check-srcroute
353 ###--------------------------------------------------------------------------
354 ### Locally-bound packet inspection.
357 clearchain inbound-untrusted
359 ## Track connections.
363 ## Allow incoming bootp. Bootp won't be forwarded, so this is obviously a
365 run iptables -A inbound -j ACCEPT \
366 -s 0.0.0.0 -d 255.255.255.255 \
367 -p udp --source-port $port_bootpc --destination-port $port_bootps
368 run iptables -A inbound -j ACCEPT \
370 -p udp --source-port $port_bootpc --destination-port $port_bootps
372 ## Allow incoming ping. This is the only ICMP left.
373 run iptables -A inbound -j ACCEPT -p icmp
374 run ip6tables -A inbound -j ACCEPT -p icmpv6
377 ## Allow unusual things.
380 ## Inspect inbound packets from untrusted sources.
381 run iptables -A inbound -s 172.29.198.0/24 -g inbound-untrusted
382 run ip6tables -A inbound -s 2001:8b0:c92:8000::/49 -g inbound-untrusted
383 run ip46tables -A inbound-untrusted -g forbidden
384 run ip46tables -A inbound -g forbidden
385 run ip46tables -A INPUT -m mark --mark $from_scary/$MASK_FROM -g inbound
386 run ip46tables -A INPUT -m mark --mark $from_untrusted/$MASK_FROM -g inbound
388 ## Allow responses from the scary outside world into the untrusted net, but
389 ## don't let untrusted things run services.
392 run ip46tables -A FORWARD -j ACCEPT \
393 -m mark --mark $(( $from_scary | $to_untrusted ))/$(( $MASK_FROM | $MASK_TO )) \
394 -m state --state ESTABLISHED,RELATED
398 ## Otherwise process as indicated by the mark.
399 for i in $inchains; do
400 run ip46tables -A $i -m mark ! --mark 0/$MASK_MASK -j ACCEPT
404 ###----- That's all, folks --------------------------------------------------