#

# rules.before

#

# Rules that should be run before the ufw command line added rules. Custom

# rules should be added to one of these chains:

#   ufw-before-input

#   ufw-before-output

#   ufw-before-forward

#



# Don't delete these required lines, otherwise there will be errors

*filter

:ufw-before-input - [0:0]

:ufw-before-output - [0:0]

:ufw-before-forward - [0:0]

:ufw-not-local - [0:0]

# End required lines





# allow all on loopback

-A ufw-before-input -i lo -j ACCEPT

-A ufw-before-output -o lo -j ACCEPT



# hand off control for sshd to sshguard

:sshguard - [0:0]

-A ufw-before-input -p tcp --dport 22 -j sshguard



# quickly process packets for which we already have a connection

-A ufw-before-input -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT

-A ufw-before-output -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT

-A ufw-before-forward -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT



# drop INVALID packets (logs these in loglevel medium and higher)

-A ufw-before-input -m conntrack --ctstate INVALID -j ufw-logging-deny

-A ufw-before-input -m conntrack --ctstate INVALID -j DROP



# ok icmp codes for INPUT

-A ufw-before-input -p icmp --icmp-type destination-unreachable -j ACCEPT

-A ufw-before-input -p icmp --icmp-type time-exceeded -j ACCEPT

-A ufw-before-input -p icmp --icmp-type parameter-problem -j ACCEPT

-A ufw-before-input -p icmp --icmp-type echo-request -j ACCEPT



# ok icmp code for FORWARD

-A ufw-before-forward -p icmp --icmp-type destination-unreachable -j ACCEPT

-A ufw-before-forward -p icmp --icmp-type time-exceeded -j ACCEPT

-A ufw-before-forward -p icmp --icmp-type parameter-problem -j ACCEPT

-A ufw-before-forward -p icmp --icmp-type echo-request -j ACCEPT



# allow dhcp client to work

-A ufw-before-input -p udp --sport 67 --dport 68 -j ACCEPT



#

# ufw-not-local

#

-A ufw-before-input -j ufw-not-local



# if LOCAL, RETURN

-A ufw-not-local -m addrtype --dst-type LOCAL -j RETURN



# if MULTICAST, RETURN

-A ufw-not-local -m addrtype --dst-type MULTICAST -j RETURN



# if BROADCAST, RETURN

-A ufw-not-local -m addrtype --dst-type BROADCAST -j RETURN



# all other non-local packets are dropped

-A ufw-not-local -m limit --limit 3/min --limit-burst 10 -j ufw-logging-deny

-A ufw-not-local -j DROP



# allow MULTICAST mDNS for service discovery (be sure the MULTICAST line above

# is uncommented)

-A ufw-before-input -p udp -d 224.0.0.251 --dport 5353 -j ACCEPT



# allow MULTICAST UPnP for service discovery (be sure the MULTICAST line above

# is uncommented)

-A ufw-before-input -p udp -d 239.255.255.250 --dport 1900 -j ACCEPT



# don't delete the 'COMMIT' line or these rules won't be processed

COMMIT