vampire.m4: Load protocol-specific NAT helper modules.

[firewall] / vampire.m4

diff --git a/vampire.m4 b/vampire.m4
index 18365be..55c7961 100644 (file)
--- a/vampire.m4
+++ b/vampire.m4
@@ -1,4 +1,4 @@
-### -*-m4-*-
+### -*-sh-*-
 ###
 ### Firewall configuration for vampire
 ###
@@ -22,16 +22,25 @@
 ### Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
 ###--------------------------------------------------------------------------
+### Config settings.
+
+## This router is involved in a routing asymmetry.
+setconf(rp_filter, 0)
+setconf(log_martians, 0)
+
+###--------------------------------------------------------------------------
 ### Network interfaces.
 
 m4_divert(44)m4_dnl
 ## Interface definitions.
-if_untrusted=eth0.1
-if_trusted=eth0.0
+if_dmz=eth0.0
+if_trusted=eth0.1
+if_safe=$if_dmz,$if_trusted
+if_untrusted=eth0.3
 if_vpn=vpn-+
 if_iodine=dns+
-if_its_mz=eth0.0
-if_its_pi=eth0.0
+if_its_mz=$if_dmz,$if_trusted
+if_its_pi=$if_dmz,$if_trusted
 
 m4_divert(-1)
 ###--------------------------------------------------------------------------
@@ -43,12 +52,13 @@ allowservices inbound tcp \
        finger ident \
        dns iodine \
        ssh \
-       smtp \
+       smtp submission \
        gnutella_svc \
        ftp ftp_data \
        rsync \
+       imaps \
        disorder mpd \
-       http https \
+       http https squid \
        git \
        tor_public tor_directory i2p
 allowservices inbound udp \
@@ -57,40 +67,56 @@ allowservices inbound udp \
        gnutella_svc \
        i2p
 
-## Provide DNS resolution to local untrusted hosts.
-for p in tcp udp; do
-  run iptables -A inbound -j ACCEPT \
-         -s 172.29.198.0/24 \
-         -p $p --destination-port $port_dns
-done
+## Extend some services to local untrusted hosts.
+clearchain inbound-untrusted
+run iptables -A inbound -j inbound-untrusted \
+       -s 172.29.198.0/24
 
-## Allow smb and nmb to untrusted hosts.  This is a bit experimental.
-run iptables -A inbound -j ACCEPT \
-       -s 172.29.198.0/24 \
-       -p udp -m multiport --destination-ports \
-               $port_netbios_ns,$port_netbios_dgm
-run iptables -A inbound -j ACCEPT \
-       -s 172.29.198.0/24 \
-       -p tcp -m multiport --destination-ports \
-               $port_netbios_ssn,$port_microsoft_ds
+allowservices inbound-untrusted tcp \
+       dns \
+       netbios_ssn microsoft_ds
+allowservices inbound-untrusted udp \
+       dns \
+       tftp
 
 ## Provide syslog for evolution.
 run iptables -A inbound -j ACCEPT \
        -s 172.29.198.2 \
        -p udp --destination-port $port_syslog
 
-## Provide a web cache to local untrusted hosts.
-run iptables -A inbound -j ACCEPT \
-       -s 172.29.198.0/24 \
-       -p tcp --destination-port $port_squid
-
 ## Watch outgoing Tor usage.
 run iptables -A OUTPUT -m multiport \
        -p tcp --source-ports $port_tor_public,$port_tor_directory
 
 ## Other interesting things.
 dnsresolver inbound
-ntpclient inbound 158.152.1.76 158.152.1.204 194.159.253.2
+ntpclient inbound $ntp_servers
+
+## NAT for RFC1918 addresses.
+for i in PREROUTING OUTPUT POSTROUTING; do
+  run iptables -t nat -P $i ACCEPT 2>/dev/null || :
+  run iptables -t nat -F $i 2>/dev/null || :
+done
+run iptables -t nat -F
+run iptables -t nat -X
+
+run iptables -t nat -N outbound
+run iptables -t nat -A outbound -j RETURN ! -o $if_dmz
+run iptables -t nat -A outbound -j RETURN ! -s 172.29.198.0/23
+run iptables -t nat -A outbound -j RETURN -d 62.49.204.144/28
+run iptables -t nat -A outbound -j RETURN -d 172.29.198.0/23
+run iptables -t nat -A outbound -j SNAT --to-source 62.49.204.158
+run iptables -t nat -A POSTROUTING -j outbound
+
+## Set up NAT protocol helpers.  In particular, SIP needs some special
+## twiddling.
+run modprobe nf_conntrack_sip \
+  ports=5060 \
+  sip_direct_signalling=0 \
+  sip_direct_media=0
+for p in ftp sip h323; do
+  run modprobe nf_nat_$p
+done
 
 m4_divert(-1)
 ###----- That's all, folks --------------------------------------------------