X-Git-Url: https://git.distorted.org.uk/~mdw/firewall/blobdiff_plain/f98dfdf667181aad1d53a6e3a3758c2c6caec3a8..d119795:/vampire.m4

diff --git a/vampire.m4 b/vampire.m4
index e5ab346..55c7961 100644
--- a/vampire.m4
+++ b/vampire.m4
@@ -1,4 +1,4 @@
-### -*-m4-*-
+### -*-sh-*-
 ###
 ### Firewall configuration for vampire
 ###
@@ -22,76 +22,101 @@
 ### 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)
 ###--------------------------------------------------------------------------
 ### vampire-specific rules.
 
-m4_divert(35)m4_dnl
-errorchain ddos-evil-dns DROP
-## Invalid DNS request with probably-forged sender address, with intent to
-## cause DDOS.
-
 m4_divert(82)m4_dnl
-## Repelling evil DDos attack.
-run ipset -N ddos-evil-dns iphash 2>/dev/null || :
-run iptables -A inbound -g ddos-evil-dns \
-	-m set --set ddos-evil-dns src \
-	-p udp --destination-port $port_dns
-
 ## Externally visible services.
 allowservices inbound tcp \
 	finger ident \
 	dns iodine \
 	ssh \
-	smtp \
+	smtp submission \
 	gnutella_svc \
 	ftp ftp_data \
 	rsync \
-	disorder \
-	http https \
-	git	
-allowservices inbound tcp \
-	tor_public tor_directory
+	imaps \
+	disorder mpd \
+	http https squid \
+	git \
+	tor_public tor_directory i2p
 allowservices inbound udp \
 	dns iodine \
 	tripe \
-	gnutella_svc
+	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
+
+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 --------------------------------------------------