| 1 | ### -*-sh-*- |
| 2 | ### |
| 3 | ### Local firewall configuration |
| 4 | ### |
| 5 | ### (c) 2008 Mark Wooding |
| 6 | ### |
| 7 | |
| 8 | ###----- Licensing notice --------------------------------------------------- |
| 9 | ### |
| 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. |
| 14 | ### |
| 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. |
| 19 | ### |
| 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. |
| 23 | |
| 24 | ###-------------------------------------------------------------------------- |
| 25 | ### Local configuration. |
| 26 | |
| 27 | m4_divert(6)m4_dnl |
| 28 | ## Default NTP servers. |
| 29 | defconf(ntp_servers, |
| 30 | "81.187.26.174 90.155.23.205 2001:8b0:0:23::205 185.73.44.6 2001:ba8:0:2c06::") |
| 31 | |
| 32 | m4_divert(-1) |
| 33 | ###-------------------------------------------------------------------------- |
| 34 | ### Packet classification. |
| 35 | |
| 36 | ## IPv4 addressing. |
| 37 | ## |
| 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. |
| 41 | ## |
| 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. |
| 45 | ## |
| 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. |
| 49 | ## |
| 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 |
| 55 | ## |
| 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 |
| 63 | |
| 64 | ## IPv6 addressing. |
| 65 | ## |
| 66 | ## There are five blocks of publicly routable IPv6 addresses, though some of |
| 67 | ## them aren't very interesting. The ranges are as follows. |
| 68 | ## |
| 69 | ## 2001:8b0:c92::/48 |
| 70 | ## Main house range (aaisp). See below for allocation policy. |
| 71 | ## There is no explicit DMZ allocation (and no need for one). |
| 72 | ## |
| 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. |
| 76 | ## |
| 77 | ## axxx Virtual, untrusted |
| 78 | ## 8xxx Untrusted |
| 79 | ## 6xxx Virtual, safe |
| 80 | ## 4xxx Safe |
| 81 | ## 0xxx Unsafe, trusted |
| 82 | ## |
| 83 | ## These have been chosen so that network properties can be deduced by |
| 84 | ## inspecting bits of the network number: |
| 85 | ## |
| 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. |
| 88 | ## |
| 89 | ## Finally, the low-order nibbles identify the site. |
| 90 | ## |
| 91 | ## 0 No specific site: mobile VPN endpoints or anycast addresses. |
| 92 | ## 1 House. |
| 93 | ## fff Local border network. |
| 94 | |
| 95 | ## Define the available network classes. |
| 96 | m4_divert(42)m4_dnl |
| 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 |
| 103 | |
| 104 | defnetclass link |
| 105 | defnetclass mcast |
| 106 | m4_divert(-1) |
| 107 | |
| 108 | m4_divert(26)m4_dnl |
| 109 | ###-------------------------------------------------------------------------- |
| 110 | ### Network layout. |
| 111 | |
| 112 | ## House networks. |
| 113 | defnet dmz trusted |
| 114 | addr 81.2.113.195 81.187.238.128/28 217.169.12.64/28 2001:8b0:c92:fff::/64 |
| 115 | via unsafe untrusted |
| 116 | defnet unsafe trusted |
| 117 | addr 172.29.199.0/25 2001:8b0:c92:1::/64 |
| 118 | via househub |
| 119 | defnet safe safe |
| 120 | addr 172.29.199.192/27 2001:8b0:c92:4001::/64 |
| 121 | via househub |
| 122 | defnet untrusted untrusted |
| 123 | addr 172.29.198.0/25 2001:8b0:c92:8001::/64 |
| 124 | via househub |
| 125 | |
| 126 | defnet househub virtual |
| 127 | via housebdry dmz unsafe safe untrusted |
| 128 | defnet housebdry virtual |
| 129 | via househub hub |
| 130 | |
| 131 | ## House hosts. |
| 132 | defhost radius |
| 133 | hosttype router |
| 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 |
| 138 | iface ppp0 default |
| 139 | iface t6-he default |
| 140 | iface vpn-precision vpn sgo |
| 141 | iface vpn-chiark sgo |
| 142 | iface vpn-+ vpn |
| 143 | defhost roadstar |
| 144 | iface eth0 dmz unsafe |
| 145 | iface eth1 dmz unsafe |
| 146 | defhost jem |
| 147 | iface eth0 dmz unsafe |
| 148 | iface eth1 dmz unsafe |
| 149 | defhost universe |
| 150 | iface eth0 dmz unsafe |
| 151 | iface eth1 dmz unsafe |
| 152 | defhost artist |
| 153 | hosttype router |
| 154 | iface eth0 dmz unsafe untrusted |
| 155 | iface eth1 dmz unsafe untrusted |
| 156 | iface eth3 unsafe untrusted |
| 157 | defhost vampire |
| 158 | hosttype router |
| 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 |
| 164 | iface vpn-chiark sgo |
| 165 | iface vpn-+ vpn |
| 166 | defhost ibanez |
| 167 | iface br-dmz dmz unsafe |
| 168 | iface br-unsafe unsafe |
| 169 | defhost orange |
| 170 | iface wlan0 untrusted |
| 171 | iface vpn-radius unsafe |
| 172 | defhost groove |
| 173 | iface eth0 unsafe |
| 174 | iface wlan0 untrusted |
| 175 | iface vpn-radius unsafe |
| 176 | |
| 177 | defhost gibson |
| 178 | hosttype client |
| 179 | iface eth0 unsafe |
| 180 | |
| 181 | ## Formerly colocated hosts. |
| 182 | defhost fender |
| 183 | iface br-dmz dmz unsafe |
| 184 | iface br-unsafe dmz unsafe |
| 185 | defhost precision |
| 186 | hosttype router |
| 187 | iface eth0 dmz unsafe vpn sgo |
| 188 | iface eth1 dmz unsafe vpn sgo |
| 189 | iface vpn-mango binswood |
| 190 | iface vpn-chiark sgo |
| 191 | iface vpn-national upn |
| 192 | iface vpn-mdwdev upn |
| 193 | iface vpn-eggle upn |
| 194 | iface vpn-+ vpn |
| 195 | defhost telecaster |
| 196 | iface eth0 dmz unsafe vpn sgo |
| 197 | iface eth1 dmz unsafe vpn sgo |
| 198 | defhost stratocaster |
| 199 | iface eth0 dmz unsafe vpn sgo |
| 200 | iface eth1 dmz unsafe vpn sgo |
| 201 | defhost jazz |
| 202 | hosttype router |
| 203 | iface eth0 dmz unsafe vpn sgo |
| 204 | iface eth1 dmz unsafe vpn sgo |
| 205 | iface dns0 iodine |
| 206 | iface hippo-svc hippotat |
| 207 | iface vpn-+ vpn |
| 208 | |
| 209 | ## Stunt connectivity networks. |
| 210 | defnet iodine untrusted |
| 211 | addr 172.29.198.128/28 |
| 212 | via colohub |
| 213 | defnet hippotat untrusted |
| 214 | addr 172.29.198.144/28 |
| 215 | via colohub |
| 216 | |
| 217 | |
| 218 | ## Other networks. |
| 219 | defnet hub virtual |
| 220 | via housebdry |
| 221 | defnet sgo noloop |
| 222 | addr !172.29.198.0/23 |
| 223 | addr !10.165.27.0/24 |
| 224 | addr 10.0.0.0/8 |
| 225 | addr 172.16.0.0/12 |
| 226 | addr 192.168.0.0/16 |
| 227 | via househub |
| 228 | defnet vpn trusted |
| 229 | addr 172.29.199.128/27 2001:8b0:c92:6000::/64 |
| 230 | via househub |
| 231 | host crybaby 1 ::1:1 |
| 232 | host terror 2 ::2:1 |
| 233 | host orange 3 ::3:1 |
| 234 | host haze 4 ::4:1 |
| 235 | host spirit 9 ::9:1 |
| 236 | host groove 10 ::10:1 |
| 237 | defnet anycast trusted |
| 238 | addr 172.29.199.224/27 2001:8b0:c92:0::/64 |
| 239 | via dmz unsafe safe untrusted vpn nvpn |
| 240 | defnet default scary |
| 241 | addr 81.2.113.195 81.187.238.128/28 217.169.12.64/28 \ |
| 242 | 2001:8b0:c92::/48 |
| 243 | via dmz unsafe untrusted |
| 244 | defnet upn untrusted |
| 245 | addr 172.29.198.160/27 2001:8b0:c92:a000::/64 |
| 246 | via househub |
| 247 | host national 1 ::1:1 |
| 248 | host mdwdev 2 ::2:1 |
| 249 | host eggle 3 ::3:1 |
| 250 | |
| 251 | ## VPS hosts. |
| 252 | defhost eggle |
| 253 | iface eth0 default |
| 254 | iface vpn-precision househub |
| 255 | defhost national |
| 256 | iface eth0 default |
| 257 | iface vpn-precision househub |
| 258 | |
| 259 | ## Satellite networks. |
| 260 | defnet binswood vpnnat |
| 261 | addr 10.165.27.0/24 |
| 262 | via househub |
| 263 | defhost mango |
| 264 | hosttype router |
| 265 | iface eth0 binswood default |
| 266 | iface vpn-precision dmz default |
| 267 | |
| 268 | m4_divert(80)m4_dnl |
| 269 | ###-------------------------------------------------------------------------- |
| 270 | ### Connection tracking helper modules. |
| 271 | |
| 272 | for i in ftp; do |
| 273 | modprobe nf_conntrack_$i |
| 274 | done |
| 275 | |
| 276 | m4_divert(80)m4_dnl |
| 277 | ###-------------------------------------------------------------------------- |
| 278 | ### Special forwarding exemptions. |
| 279 | |
| 280 | case $forward in |
| 281 | 1) |
| 282 | |
| 283 | ## Only allow these packets if they're not fragmented. (Don't trust safe |
| 284 | ## hosts's fragment reassembly to be robust against malicious fragments.) |
| 285 | ## There's a hideous bug in iptables 1.4.11.1 which botches the meaning |
| 286 | ## of `! -f', so we do the negation using early return from a subchain. |
| 287 | clearchain fwd-spec-nofrag |
| 288 | run iptables -A fwd-spec-nofrag -j RETURN --fragment |
| 289 | run ip6tables -A fwd-spec-nofrag -j RETURN \ |
| 290 | -m ipv6header --soft --header frag |
| 291 | run ip46tables -A FORWARD -j fwd-spec-nofrag |
| 292 | |
| 293 | ## Allow ping from safe/noloop to untrusted networks. |
| 294 | run iptables -A fwd-spec-nofrag -j ACCEPT \ |
| 295 | -p icmp --icmp-type echo-request \ |
| 296 | -m mark --mark $to_untrusted/$MASK_TO |
| 297 | run iptables -A fwd-spec-nofrag -j ACCEPT \ |
| 298 | -p icmp --icmp-type echo-reply \ |
| 299 | -m mark --mark $from_untrusted/$MASK_FROM \ |
| 300 | -m state --state ESTABLISHED |
| 301 | run ip6tables -A fwd-spec-nofrag -j ACCEPT \ |
| 302 | -p icmpv6 --icmpv6-type echo-request \ |
| 303 | -m mark --mark $to_untrusted/$MASK_TO |
| 304 | run ip6tables -A fwd-spec-nofrag -j ACCEPT \ |
| 305 | -p icmpv6 --icmpv6-type echo-reply \ |
| 306 | -m mark --mark $from_untrusted/$MASK_FROM \ |
| 307 | -m state --state ESTABLISHED |
| 308 | |
| 309 | ## Allow SSH from safe/noloop to untrusted networks. |
| 310 | run ip46tables -A fwd-spec-nofrag -j ACCEPT \ |
| 311 | -p tcp --destination-port $port_ssh \ |
| 312 | -m mark --mark $to_untrusted/$MASK_TO |
| 313 | run ip46tables -A fwd-spec-nofrag -j ACCEPT \ |
| 314 | -p tcp --source-port $port_ssh \ |
| 315 | -m mark --mark $from_untrusted/$MASK_FROM \ |
| 316 | -m state --state ESTABLISHED |
| 317 | |
| 318 | ;; |
| 319 | esac |
| 320 | |
| 321 | m4_divert(80)m4_dnl |
| 322 | ###-------------------------------------------------------------------------- |
| 323 | ### Kill things we don't understand properly. |
| 324 | ### |
| 325 | ### I don't like having to do this, but since I don't know how to do proper |
| 326 | ### multicast filtering, I'm just going to ban it from being forwarded. |
| 327 | |
| 328 | errorchain poorly-understood REJECT |
| 329 | |
| 330 | ## Ban multicast destination addresses in forwarding. |
| 331 | case $forward in |
| 332 | 1) |
| 333 | run iptables -A FORWARD -g poorly-understood \ |
| 334 | -d 224.0.0.0/4 |
| 335 | run ip6tables -A FORWARD -g poorly-understood \ |
| 336 | -d ff::/8 |
| 337 | ;; |
| 338 | esac |
| 339 | |
| 340 | m4_divert(82)m4_dnl |
| 341 | ###-------------------------------------------------------------------------- |
| 342 | ### Check for source routing. |
| 343 | |
| 344 | clearchain check-srcroute |
| 345 | |
| 346 | run iptables -A check-srcroute -g forbidden \ |
| 347 | -m ipv4options --any --flags lsrr,ssrr |
| 348 | run ip6tables -A check-srcroute -g forbidden \ |
| 349 | -m rt |
| 350 | |
| 351 | for c in INPUT FORWARD; do |
| 352 | for m in $from_scary $from_untrusted; do |
| 353 | run ip46tables -A $c -m mark --mark $m/$MASK_FROM -j check-srcroute |
| 354 | done |
| 355 | done |
| 356 | |
| 357 | m4_divert(84)m4_dnl |
| 358 | ###-------------------------------------------------------------------------- |
| 359 | ### Locally-bound packet inspection. |
| 360 | |
| 361 | clearchain inbound |
| 362 | clearchain inbound-untrusted |
| 363 | |
| 364 | ## Track connections. |
| 365 | commonrules inbound |
| 366 | conntrack inbound |
| 367 | |
| 368 | ## Allow incoming bootp. Bootp won't be forwarded, so this is obviously a |
| 369 | ## local request. |
| 370 | run iptables -A inbound -j ACCEPT \ |
| 371 | -s 0.0.0.0 -d 255.255.255.255 \ |
| 372 | -p udp --source-port $port_bootpc --destination-port $port_bootps |
| 373 | run iptables -A inbound -j ACCEPT \ |
| 374 | -s 172.29.198.0/23 \ |
| 375 | -p udp --source-port $port_bootpc --destination-port $port_bootps |
| 376 | |
| 377 | ## Allow incoming ping. This is the only ICMP left. |
| 378 | run iptables -A inbound -j ACCEPT -p icmp |
| 379 | run ip6tables -A inbound -j ACCEPT -p icmpv6 |
| 380 | |
| 381 | m4_divert(88)m4_dnl |
| 382 | ## Allow unusual things. |
| 383 | openports inbound |
| 384 | |
| 385 | ## Inspect inbound packets from untrusted sources. |
| 386 | run iptables -A inbound -s 172.29.198.0/24 -g inbound-untrusted |
| 387 | run ip6tables -A inbound -s 2001:8b0:c92:8000::/49 -g inbound-untrusted |
| 388 | run ip46tables -A inbound-untrusted -g forbidden |
| 389 | run ip46tables -A inbound -g forbidden |
| 390 | run ip46tables -A INPUT -m mark --mark $from_scary/$MASK_FROM -g inbound |
| 391 | run ip46tables -A INPUT -m mark --mark $from_untrusted/$MASK_FROM -g inbound |
| 392 | |
| 393 | ## Allow responses from the scary outside world into the untrusted net, but |
| 394 | ## don't let untrusted things run services. |
| 395 | case $forward in |
| 396 | 1) |
| 397 | run ip46tables -A FORWARD -j ACCEPT \ |
| 398 | -m mark --mark $(( $from_scary | $to_untrusted ))/$(( $MASK_FROM | $MASK_TO )) \ |
| 399 | -m state --state ESTABLISHED,RELATED |
| 400 | ;; |
| 401 | esac |
| 402 | |
| 403 | ## Otherwise process as indicated by the mark. |
| 404 | for i in $inchains; do |
| 405 | run ip46tables -A $i -m mark ! --mark 0/$MASK_MASK -j ACCEPT |
| 406 | done |
| 407 | |
| 408 | m4_divert(-1) |
| 409 | ###----- That's all, folks -------------------------------------------------- |