mdw@git.distorted.org.uk Git - firewall/blob - local.m4

   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 ## Define the available network classes.
  37 m4_divert(42)m4_dnl
  38 defnetclass untrusted untrusted trusted
  39 defnetclass trusted untrusted trusted safe noloop
  40 defnetclass safe trusted safe noloop
  41 defnetclass noloop trusted safe
  42 m4_divert(-1)
  43
  44 m4_divert(26)m4_dnl
  45 ###--------------------------------------------------------------------------
  46 ### Network layout.
  47
  48 ## House networks.
  49 defnet dmz trusted
  50         addr 62.49.204.144/28 2001:470:1f09:1b98::/64
  51         forwards unsafe untrusted
  52 defnet unsafe trusted
  53         addr 172.29.199.0/25 2001:470:9740:1::/64
  54         forwards househub
  55 defnet safe safe
  56         addr 172.29.199.192/27 2001:470:9740:4001::/64
  57         forwards househub
  58 defnet untrusted untrusted
  59         addr 172.29.198.0/25 2001:470:9740:8001::/64
  60         forwards househub
  61 defnet vpn safe
  62         addr 172.29.199.128/27 2001:ba8:1d9:6000::/64
  63         forwards househub colohub
  64         host crybaby 1
  65         host terror 2
  66 defnet iodine untrusted
  67         addr 172.29.198.128/28
  68
  69 defnet househub virtual
  70         forwards housebdry dmz unsafe safe untrusted
  71 defnet housebdry virtual
  72         forwards househub hub
  73         noxit dmz
  74
  75 ## House hosts.
  76 defhost radius
  77         router
  78         iface eth0 dmz unsafe safe
  79         iface eth1 dmz unsafe safe
  80         iface eth2 safe
  81         iface eth3 untrusted
  82 defhost roadstar
  83         iface eth0 dmz unsafe
  84         iface eth1 dmz unsafe
  85 defhost jem
  86         iface eth0 dmz unsafe
  87         iface eth1 dmz unsafe
  88 defhost artist
  89         iface eth0 dmz unsafe
  90         iface eth1 dmz unsafe
  91 defhost vampire
  92         router
  93         iface eth0.0 dmz unsafe safe
  94         iface eth0.1 dmz unsafe safe
  95         iface eth0.2 safe
  96         iface eth0.3 untrusted
  97         iface dns0 dns
  98         iface vpn-+ vpn
  99         iface vpn-precision colobdry vpn
 100 defhost ibanez
 101         iface br-dmz dmz unsafe
 102         iface br-unsafe unsafe
 103
 104 defhost gibson
 105         iface eth0 unsafe
 106
 107 ## Colocated networks.
 108 defnet jump trusted
 109         addr 212.13.198.64/28 2001:ba8:0:1d9::/64
 110         forwards colohub
 111 defnet colo trusted
 112         addr 172.29.199.176/28 2001:ba8:1d9:2::/64
 113         forwards colohub
 114 defnet colohub virtual
 115         forwards colobdry jump colo
 116 defnet colobdry virtual
 117         forwards colohub hub
 118         noxit jump
 119
 120 ## Colocated hosts.
 121 defhost fender
 122         iface br-jump jump colo
 123         iface br-colo jump colo
 124 defhost precision
 125         router
 126         iface eth0 jump colo
 127         iface eth1 jump colo
 128         iface vpn-+ vpn
 129         iface vpn-vampire housebdry vpn
 130 defhost telecaster
 131         iface eth0 jump colo
 132         iface eth1 jump colo
 133 defhost stratocaster
 134         iface eth0 jump colo
 135         iface eth1 jump colo
 136 defhost jazz
 137         iface eth0 jump colo
 138         iface eth1 jump colo
 139
 140 ## Other networks.
 141 defnet hub virtual
 142         forwards housebdry colobdry
 143 defnet default untrusted
 144         addr 62.49.204.144/28 2001:470:1f09:1b98::/64
 145         addr 212.13.198.64/28 2001:ba8:0:1d9::/64
 146         addr 2001:ba8:1d9::/48 #temporary
 147         forwards dmz untrusted unsafe jump colo
 148
 149 m4_divert(80)m4_dnl
 150 ###--------------------------------------------------------------------------
 151 ### Special forwarding exemptions.
 152
 153 case $forward in
 154   1)
 155
 156     ## Only allow these packets if they're not fragmented.  (Don't trust safe
 157     ## hosts's fragment reassembly to be robust against malicious fragments.)
 158     ## There's a hideous bug in iptables 1.4.11.1 which botches the meaning
 159     ## of `! -f', so we do the negation using early return from a subchain.
 160     clearchain fwd-spec-nofrag
 161     run iptables -A fwd-spec-nofrag -j RETURN --fragment
 162     run ip6tables -A fwd-spec-nofrag -j RETURN \
 163             -m ipv6header --soft --header frag
 164     run iptables -A FORWARD -j fwd-spec-nofrag
 165
 166     ## Allow ping from safe/noloop to untrusted networks.
 167     run iptables -A fwd-spec-nofrag -j ACCEPT \
 168             -p icmp --icmp-type echo-request \
 169             -m mark --mark $to_untrusted/$MASK_TO
 170     run iptables -A fwd-spec-nofrag -j ACCEPT \
 171             -p icmp --icmp-type echo-reply \
 172             -m mark --mark $from_untrusted/$MASK_FROM \
 173             -m state --state ESTABLISHED
 174     run ip6tables -A fwd-spec-nofrag -j ACCEPT \
 175             -p icmpv6 --icmpv6-type echo-request \
 176             -m mark --mark $to_untrusted/$MASK_TO
 177     run ip6tables -A fwd-spec-nofrag -j ACCEPT \
 178             -p icmpv6 --icmpv6-type echo-reply \
 179             -m mark --mark $from_untrusted/$MASK_FROM \
 180             -m state --state ESTABLISHED
 181
 182     ## Allow SSH from safe/noloop to untrusted networks.
 183     run iptables -A fwd-spec-nofrag -j ACCEPT \
 184             -p tcp --destination-port $port_ssh \
 185             -m mark --mark $to_untrusted/$MASK_TO
 186     run iptables -A fwd-spec-nofrag -j ACCEPT \
 187             -p tcp --source-port $port_ssh \
 188             -m mark --mark $from_untrusted/$MASK_FROM \
 189             -m state --state ESTABLISHED
 190     run ip6tables -A fwd-spec-nofrag -j ACCEPT \
 191             -p tcp --destination-port $port_ssh \
 192             -m mark --mark $to_untrusted/$MASK_TO
 193     run ip6tables -A fwd-spec-nofrag -j ACCEPT \
 194             -p tcp --source-port $port_ssh \
 195             -m mark --mark $from_untrusted/$MASK_FROM \
 196             -m state --state ESTABLISHED
 197
 198     ;;
 199 esac
 200
 201 m4_divert(80)m4_dnl
 202 ###--------------------------------------------------------------------------
 203 ### Kill things we don't understand properly.
 204 ###
 205 ### I don't like having to do this, but since I don't know how to do proper
 206 ### multicast filtering, I'm just going to ban it from being forwarded.
 207
 208 errorchain poorly-understood REJECT
 209
 210 ## Ban multicast destination addresses in forwarding.
 211 case $forward in
 212   1)
 213     run iptables -A FORWARD -g poorly-understood \
 214             -d 224.0.0.0/4
 215     run ip6tables -A FORWARD -g poorly-understood \
 216             -d ff::/8
 217     ;;
 218 esac
 219
 220 m4_divert(84)m4_dnl
 221 ###--------------------------------------------------------------------------
 222 ### Locally-bound packet inspection.
 223
 224 clearchain inbound
 225
 226 ## Track connections.
 227 commonrules inbound
 228 conntrack inbound
 229
 230 ## Allow incoming bootp.  Bootp won't be forwarded, so this is obviously a
 231 ## local request.
 232 run iptables -A inbound -j ACCEPT \
 233         -s 0.0.0.0 -d 255.255.255.255 \
 234         -p udp --source-port $port_bootpc --destination-port $port_bootps
 235 run iptables -A inbound -j ACCEPT \
 236         -s 172.29.198.0/23 \
 237         -p udp --source-port $port_bootpc --destination-port $port_bootps
 238
 239 ## Incoming multicast on a network interface associated with a trusted
 240 ## network is OK, since it must have originated there (or been forwarded, but
 241 ## we don't do that yet).
 242 seen=:-:
 243 for net in $allnets; do
 244   eval class=\$net_class_$net
 245   case $class in trusted) ;; *) continue ;; esac
 246   for iface in $(net_interfaces FWHOST $net); do
 247     case "$seen" in *:$iface:*) continue ;; esac
 248     seen=$seen$iface:
 249     run iptables -A inbound -j ACCEPT \
 250         -s 0.0.0.0 -d 224.0.0.0/24 \
 251         -i $iface
 252   done
 253 done
 254
 255 ## Allow incoming ping.  This is the only ICMP left.
 256 run ip46tables -A inbound -j ACCEPT -p icmp
 257
 258 m4_divert(88)m4_dnl
 259 ## Allow unusual things.
 260 openports inbound
 261
 262 ## Inspect inbound packets from untrusted sources.
 263 run ip46tables -A inbound -j forbidden
 264 run ip46tables -A INPUT -m mark --mark $from_untrusted/$MASK_FROM -g inbound
 265
 266 ## Otherwise process as indicated by the mark.
 267 for i in $inchains; do
 268   run ip46tables -A $i -m mark ! --mark 0/$MASK_MASK -j ACCEPT
 269 done
 270
 271 m4_divert(-1)
 272 ###----- That's all, folks --------------------------------------------------