4 # Rules that should be run before the ufw command line added rules. Custom
5 # rules should be added to one of these chains:
11 # Don't delete these required lines, otherwise there will be errors
13 :ufw-before-input - [0:0]
14 :ufw-before-output - [0:0]
15 :ufw-before-forward - [0:0]
16 :ufw-not-local - [0:0]
20 # allow all on loopback
21 -A ufw-before-input -i lo -j ACCEPT
22 -A ufw-before-output -i lo -j ACCEPT
24 # connection tracking rules
25 -A ufw-before-input -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
26 -A ufw-before-forward -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
28 # drop INVALID packets
29 # uncomment to log INVALID packets
30 -A ufw-before-input -m conntrack --ctstate INVALID -j LOG --log-prefix "[UFW BLOCK INVALID]: " --log-level err -m limit --limit 3/min --limit-burst 10
31 -A ufw-before-input -m conntrack --ctstate INVALID -j DROP
33 ## Ingress filter (see RFC 2827) (eth0:LAN<192.168.100.0/24>)
34 -A ufw-before-forward -i eth0 -s ! 192.168.100.0/24 -j LOG --log-tcp-options --log-ip-options --log-prefix "[UFW BLOCK LOG_INGRESS]: " --log-level err -m limit --limit 3/min --limit-burst 10
35 -A ufw-before-forward -i eth0 -s ! 192.168.100.0/24 -j DROP
37 ## DROP CIFS(Samba) access from/to WAN(eth1)
38 -A ufw-before-input -i eth1 -p tcp -m multiport --dports 135,137:139,445 -j DROP
39 -A ufw-before-input -i eth1 -p udp -m multiport --dports 135,137:139,445 -j DROP
40 -A ufw-before-forward -i eth1 -p tcp -m multiport --dports 135,137:139,445 -j DROP
41 -A ufw-before-forward -i eth1 -p udp -m multiport --dports 135,137:139,445 -j DROP
42 -A ufw-before-forward -o eth1 -p tcp -m multiport --dports 135,137:139,445 -j DROP
43 -A ufw-before-forward -o eth1 -p udp -m multiport --dports 135,137:139,445 -j DROP
44 -A ufw-before-output -o eth1 -p tcp -m multiport --dports 135,137:139,445 -j DROP
45 -A ufw-before-output -o eth1 -p udp -m multiport --dports 135,137:139,445 -j DROP
48 -A ufw-before-input -i eth0 -j ACCEPT
49 -A ufw-before-forward -i eth0 -j ACCEPT
51 # connection tracking for outbound
52 -A ufw-before-output -p tcp -m state --state NEW,ESTABLISHED,RELATED -j ACCEPT
53 -A ufw-before-output -p udp -m state --state NEW,ESTABLISHED,RELATED -j ACCEPT
56 -A ufw-before-input -p icmp --icmp-type destination-unreachable -j ACCEPT
57 -A ufw-before-input -p icmp --icmp-type source-quench -j ACCEPT
58 -A ufw-before-input -p icmp --icmp-type time-exceeded -j ACCEPT
59 -A ufw-before-input -p icmp --icmp-type parameter-problem -j ACCEPT
60 -A ufw-before-input -p icmp --icmp-type echo-request -j ACCEPT
62 # allow dhcp client to work
63 -A ufw-before-input -p udp --sport 67 --dport 68 -j ACCEPT
68 -A ufw-before-input -j ufw-not-local
71 -A ufw-not-local -m addrtype --dst-type LOCAL -j RETURN
73 # if MULTICAST, RETURN
74 -A ufw-not-local -m addrtype --dst-type MULTICAST -j RETURN
76 # if BROADCAST, RETURN
77 -A ufw-not-local -m addrtype --dst-type BROADCAST -j RETURN
79 -A ufw-not-local -m limit --limit 3/min --limit-burst 10 -j LOG --log-prefix "[UFW BLOCK NOT-TO-ME]: " --log-level err
81 # all other non-local packets are dropped
82 -A ufw-not-local -j DROP
84 # allow MULTICAST, be sure the MULTICAST line above is uncommented
85 -A ufw-before-input -s 224.0.0.0/4 -j ACCEPT
86 -A ufw-before-input -d 224.0.0.0/4 -j ACCEPT
89 # don't delete the 'COMMIT' line or these rules won't be processed