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

   1 ### -*-sh-*-
   2 ###
   3 ### Firewall configuration for fender actual
   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 ### fender-specific rules.
  26
  27 m4_divert(86)m4_dnl
  28 ## Externally visible services.
  29 allowservices inbound tcp \
  30         ssh \
  31         ident
  32
  33 ## We have to provide NTP service.  The guests sync to our clock.
  34 ntpclient inbound $ntp_servers
  35
  36 ## Provide NTP service to untrusted clients.
  37 iptables -A inbound -p udp -j ACCEPT \
  38         --source-port 123 --destination-port 123 \
  39         -s 172.29.198.0/23
  40 ip6tables -A inbound -p udp -j ACCEPT \
  41         --source-port 123 --destination-port 123 \
  42         -s 2001:470:9740::/48
  43
  44 ## Guaranteed black hole.  Put this at the very front of the chain.
  45 run iptables -I INPUT -d 212.13.198.78 -j DROP
  46 run ip6tables -I INPUT -d 2001:ba8:0:1d9::ffff -j DROP
  47
  48 ## Ethernet bridge-level filtering for source addresses.
  49 run ebtables -F
  50 for i in log limit ip ip6; do run modprobe ebt-$i; done
  51
  52 for c in bad-source-addr check-eth0 bcp38 check-bcp38; do
  53   run ebtables -X $c >/dev/null 2>&1 || :
  54 done
  55
  56 for ch in bad-source-addr bcp38; do
  57   run ebtables -N $ch
  58   run ebtables -A $ch \
  59           --limit 20/second --limit-burst 100 \
  60           --log-prefix "fw: $ch(br)" --log-ip --log-ip6
  61   run ebtables -A $ch -j DROP
  62 done
  63
  64 run ebtables -N check-eth0
  65 run ebtables -A check-eth0 -j RETURN -p ip --ip-source ! 212.13.198.64/28
  66 run ebtables -A check-eth0 -j RETURN -p ip6 --ip6-source 2001:ba8:0:1d9::1
  67 run ebtables -A check-eth0 -j bad-source-addr \
  68         -p ip6 --ip6-source 2001:ba8:1d9::/48
  69 run ebtables -A check-eth0 -j bad-source-addr \
  70         -p ip6 --ip6-source 2001:ba8:0:1d9::/64
  71 run ebtables -A check-eth0 -j RETURN -p ip6
  72 run ebtables -A check-eth0 -j RETURN -p ip --ip-source 212.13.198.64/30
  73 run ebtables -A check-eth0 -j RETURN -p ip --ip-source 212.13.198.68
  74 run ebtables -A check-eth0 -j bad-source-addr -p ip
  75 run ebtables -A INPUT -j check-eth0 -i bond0
  76 run ebtables -A FORWARD -j check-eth0 -i bond0
  77
  78 run ebtables -N check-bcp38
  79 run ebtables -A check-bcp38 -j RETURN -p ip --ip-source 212.13.198.64/28
  80 run ebtables -A check-bcp38 -j bcp38 -p ip
  81 run ebtables -A check-bcp38 -j RETURN -p ip6 --ip6-source 2001:ba8:0:1d9::/64
  82 run ebtables -A check-bcp38 -j RETURN -p ip6 --ip6-source 2001:ba8:1d9::/48
  83 run ebtables -A check-bcp38 -j RETURN -p ip6 --ip6-source fe80::/10
  84 run ebtables -A check-bcp38 -j bcp38 -p ip6
  85 run ebtables -A FORWARD -j check-bcp38 -o bond0
  86
  87 ## There's a hideous bug in Linux' 3.2.51-1's ebtables: for some reason it
  88 ## misparses (at least) locally originated multicast packets, and tries to
  89 ## extract IP header fields relative to the start of the Ethernet frame.  The
  90 ## result is obviously a hideous mess.  Don't try to do BCP38 checking for
  91 ## locally originated packets until this is fixed.
  92 ##run ebtables -A OUTPUT -j check-bcp38 -o bond0
  93
  94 m4_divert(-1)
  95 ###----- That's all, folks --------------------------------------------------