| 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 | "158.152.1.76 158.152.1.204 194.159.253.2 195.173.57.232") |
| 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 | ## 62.49.204.144/28 |
| 43 | ## House border network (dmz). We have all of these, but .145 |
| 44 | ## is reserved for the router. |
| 45 | ## |
| 46 | ## 212.13.18.64/28 |
| 47 | ## Jump colocated network (jump). .65--68 are used by Jump |
| 48 | ## network infrastructure; we get the rest. |
| 49 | ## |
| 50 | ## The latter is the block 172.29.196.0/22. Currently the low half is |
| 51 | ## unallocated (and may be returned to the G-RIN); the remaining addresses |
| 52 | ## are allocated as follows. |
| 53 | ## |
| 54 | ## 172.29.198.0/24 Untrusted networks. |
| 55 | ## .0/25 house wireless net |
| 56 | ## .128/28 iodine (IP-over-DNS) network |
| 57 | ## |
| 58 | ## 172.29.199.0/24 Trusted networks. |
| 59 | ## .0/25 house wired network |
| 60 | ## .128/27 mobile VPN hosts |
| 61 | ## .160/28 reserved, except .160/30 allocated for ITS |
| 62 | ## .176/28 internal colocated network |
| 63 | ## .192/27 house safe network |
| 64 | ## .224/27 anycast services |
| 65 | |
| 66 | ## IPv6 addressing. |
| 67 | ## |
| 68 | ## There are five blocks of publicly routable IPv6 addresses, though some of |
| 69 | ## them aren't very interesting. The ranges are as follows. |
| 70 | ## |
| 71 | ## 2001:470:1f08:1b98::/64 |
| 72 | ## Hurricane Electric tunnel network: only :1 (HE) and :2 |
| 73 | ## (radius) are used. |
| 74 | ## |
| 75 | ## 2001:470:1f09:1b98::/64 |
| 76 | ## House border network (dmz). |
| 77 | ## |
| 78 | ## 2001:470:9740::/48 |
| 79 | ## Main house range. See below for allocation policy. |
| 80 | ## |
| 81 | ## 2001:ba8:0:1d9::/64 |
| 82 | ## Jump border network (jump): :1 is the router (supplied by |
| 83 | ## Jump); other addresses are ours. |
| 84 | ## |
| 85 | ## 2001:ba8:1d9::/48 |
| 86 | ## Main colocated range. See below for allocation policy. |
| 87 | ## |
| 88 | ## Addresses in the /64 networks are simply allocated in ascending order. |
| 89 | ## The /48s are split into /64s by appending a 16-bit network number. The |
| 90 | ## top nibble of the network number classifies the network, as follows. |
| 91 | ## |
| 92 | ## 8xxx Untrusted |
| 93 | ## 6xxx Virtual, safe |
| 94 | ## 4xxx Safe |
| 95 | ## 0xxx Unsafe, trusted |
| 96 | ## |
| 97 | ## These have been chosen so that network properties can be deduced by |
| 98 | ## inspecting bits of the network number: |
| 99 | ## |
| 100 | ## Bit 15 If set, the network is untrusted; otherwise it is trusted. |
| 101 | ## Bit 14 If set, the network is safe; otherwise it is unsafe. |
| 102 | ## |
| 103 | ## Finally, the low-order nibbles identify the site. |
| 104 | ## |
| 105 | ## 0 No specific site: mobile VPN endpoints or anycast addresses. |
| 106 | ## 1 House. |
| 107 | ## 2 Jump colocation. |
| 108 | ## |
| 109 | ## Usually site-0 networks are allocated from the Jump range to improve |
| 110 | ## expected performance from/to external sites which don't engage in our |
| 111 | ## dynamic routing protocols. |
| 112 | |
| 113 | ## Define the available network classes. |
| 114 | m4_divert(42)m4_dnl |
| 115 | defnetclass untrusted untrusted trusted mcast |
| 116 | defnetclass trusted untrusted trusted safe noloop mcast |
| 117 | defnetclass safe trusted safe noloop mcast |
| 118 | defnetclass noloop trusted safe mcast |
| 119 | |
| 120 | defnetclass link |
| 121 | defnetclass mcast |
| 122 | m4_divert(-1) |
| 123 | |
| 124 | m4_divert(26)m4_dnl |
| 125 | ###-------------------------------------------------------------------------- |
| 126 | ### Network layout. |
| 127 | |
| 128 | ## House networks. |
| 129 | defnet dmz trusted |
| 130 | addr 62.49.204.144/28 2001:470:1f09:1b98::/64 |
| 131 | via unsafe untrusted |
| 132 | defnet unsafe trusted |
| 133 | addr 172.29.199.0/25 2001:470:9740:1::/64 |
| 134 | via househub |
| 135 | defnet safe safe |
| 136 | addr 172.29.199.192/27 2001:470:9740:4001::/64 |
| 137 | via househub |
| 138 | defnet untrusted untrusted |
| 139 | addr 172.29.198.0/25 2001:470:9740:8001::/64 |
| 140 | via househub |
| 141 | |
| 142 | defnet househub virtual |
| 143 | via housebdry dmz unsafe safe untrusted |
| 144 | defnet housebdry virtual |
| 145 | via househub hub |
| 146 | noxit dmz |
| 147 | |
| 148 | ## House hosts. |
| 149 | defhost radius |
| 150 | hosttype router |
| 151 | iface eth0 dmz unsafe safe untrusted vpn sgo colobdry default |
| 152 | iface eth1 dmz unsafe safe untrusted vpn sgo colobdry default |
| 153 | iface eth2 dmz unsafe safe untrusted vpn sgo colobdry |
| 154 | iface eth3 unsafe untrusted vpn default |
| 155 | iface ppp0 default |
| 156 | iface t6-he default |
| 157 | iface vpn-precision colobdry vpn sgo |
| 158 | iface vpn-chiark sgo |
| 159 | iface vpn-+ vpn |
| 160 | defhost roadstar |
| 161 | iface eth0 dmz unsafe |
| 162 | iface eth1 dmz unsafe |
| 163 | defhost jem |
| 164 | iface eth0 dmz unsafe |
| 165 | iface eth1 dmz unsafe |
| 166 | defhost artist |
| 167 | hosttype router |
| 168 | iface eth0 dmz unsafe untrusted |
| 169 | iface eth1 dmz unsafe untrusted |
| 170 | iface eth3 unsafe untrusted |
| 171 | defhost vampire |
| 172 | hosttype router |
| 173 | iface eth0.4 dmz unsafe untrusted safe vpn sgo colobdry |
| 174 | iface eth0.5 dmz unsafe untrusted safe vpn sgo colobdry |
| 175 | iface eth0.6 dmz unsafe safe untrusted vpn sgo colobdry |
| 176 | iface eth0.7 unsafe untrusted vpn |
| 177 | iface vpn-precision colobdry vpn sgo |
| 178 | iface vpn-chiark sgo |
| 179 | iface vpn-+ vpn |
| 180 | defhost ibanez |
| 181 | iface br-dmz dmz unsafe |
| 182 | iface br-unsafe unsafe |
| 183 | defhost orange |
| 184 | iface wlan0 untrusted |
| 185 | iface vpn-radius unsafe |
| 186 | |
| 187 | defhost gibson |
| 188 | hosttype client |
| 189 | iface eth0 unsafe |
| 190 | |
| 191 | ## Colocated networks. |
| 192 | defnet jump trusted |
| 193 | addr 212.13.198.64/28 2001:ba8:0:1d9::/64 |
| 194 | via colohub |
| 195 | defnet colo trusted |
| 196 | addr 172.29.199.176/28 2001:ba8:1d9:2::/64 |
| 197 | via colohub |
| 198 | defnet colohub virtual |
| 199 | via colobdry jump colo |
| 200 | defnet colobdry virtual |
| 201 | via colohub hub |
| 202 | noxit jump |
| 203 | defnet iodine untrusted |
| 204 | addr 172.29.198.128/28 |
| 205 | via colohub |
| 206 | |
| 207 | ## Colocated hosts. |
| 208 | defhost fender |
| 209 | iface br-jump jump colo |
| 210 | iface br-colo jump colo |
| 211 | defhost precision |
| 212 | hosttype router |
| 213 | iface eth0 jump colo vpn sgo |
| 214 | iface eth1 jump colo vpn sgo |
| 215 | iface vpn-mango binswood |
| 216 | iface vpn-radius housebdry vpn sgo |
| 217 | iface vpn-chiark sgo |
| 218 | iface vpn-+ vpn |
| 219 | defhost telecaster |
| 220 | iface eth0 jump colo |
| 221 | iface eth1 jump colo |
| 222 | defhost stratocaster |
| 223 | iface eth0 jump colo |
| 224 | iface eth1 jump colo |
| 225 | defhost jaguar |
| 226 | iface eth0 jump |
| 227 | defhost jazz |
| 228 | hosttype router |
| 229 | iface eth0 jump colo vpn |
| 230 | iface eth1 jump colo vpn |
| 231 | iface dns0 iodine |
| 232 | iface vpn-+ vpn |
| 233 | |
| 234 | ## Other networks. |
| 235 | defnet hub virtual |
| 236 | via housebdry colobdry |
| 237 | defnet sgo noloop |
| 238 | addr !172.29.198.0/23 |
| 239 | addr 10.0.0.0/8 |
| 240 | addr 172.16.0.0/12 |
| 241 | addr 192.168.0.0/16 |
| 242 | via househub colohub |
| 243 | defnet vpn safe |
| 244 | addr 172.29.199.128/27 2001:ba8:1d9:6000::/64 |
| 245 | via househub colohub |
| 246 | host crybaby 1 ::1:1 |
| 247 | host terror 2 ::2:1 |
| 248 | host orange 3 ::3:1 |
| 249 | defnet anycast trusted |
| 250 | addr 172.29.199.224/27 2001:ba8:1d9:0::/64 |
| 251 | via dmz unsafe safe untrusted jump colo vpn |
| 252 | defnet default untrusted |
| 253 | addr 62.49.204.144/28 2001:470:1f09:1b98::/64 |
| 254 | addr 212.13.198.64/28 2001:ba8:0:1d9::/64 |
| 255 | addr 2001:ba8:1d9::/48 #temporary |
| 256 | via dmz unsafe untrusted jump colo |
| 257 | |
| 258 | ## Satellite networks. |
| 259 | defnet binswood noloop |
| 260 | addr 10.165.27.0/24 |
| 261 | via colohub |
| 262 | |
| 263 | defhost mango |
| 264 | hosttype router |
| 265 | iface eth0 binswood default |
| 266 | iface vpn-precision colo |
| 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(84)m4_dnl |
| 341 | ###-------------------------------------------------------------------------- |
| 342 | ### Locally-bound packet inspection. |
| 343 | |
| 344 | clearchain inbound |
| 345 | |
| 346 | ## Track connections. |
| 347 | commonrules inbound |
| 348 | conntrack inbound |
| 349 | |
| 350 | ## Allow incoming bootp. Bootp won't be forwarded, so this is obviously a |
| 351 | ## local request. |
| 352 | run iptables -A inbound -j ACCEPT \ |
| 353 | -s 0.0.0.0 -d 255.255.255.255 \ |
| 354 | -p udp --source-port $port_bootpc --destination-port $port_bootps |
| 355 | run iptables -A inbound -j ACCEPT \ |
| 356 | -s 172.29.198.0/23 \ |
| 357 | -p udp --source-port $port_bootpc --destination-port $port_bootps |
| 358 | |
| 359 | ## Allow incoming ping. This is the only ICMP left. |
| 360 | run ip46tables -A inbound -j ACCEPT -p icmp |
| 361 | |
| 362 | m4_divert(88)m4_dnl |
| 363 | ## Allow unusual things. |
| 364 | openports inbound |
| 365 | |
| 366 | ## Inspect inbound packets from untrusted sources. |
| 367 | run ip46tables -A inbound -j forbidden |
| 368 | run ip46tables -A INPUT -m mark --mark $from_untrusted/$MASK_FROM -g inbound |
| 369 | |
| 370 | ## Otherwise process as indicated by the mark. |
| 371 | for i in $inchains; do |
| 372 | run ip46tables -A $i -m mark ! --mark 0/$MASK_MASK -j ACCEPT |
| 373 | done |
| 374 | |
| 375 | m4_divert(-1) |
| 376 | ###----- That's all, folks -------------------------------------------------- |