*filter
:INPUT DROP [0:0]
:FORWARD DROP [0:0]
:OUTPUT DROP [0:0]

###################################################################
# Simple tcp filter template. $ARG1 is the port number.
#
# Usage:  $ARG1 in this template is replaced by 5001 from command line below
#
#   firejail --net=eth0 --ip=192.168.1.105 --netfilter=/etc/firejail/tcpserver.net,5001 server-program
#
###################################################################

# allow server traffic
-A INPUT -p tcp --dport $ARG1 -m state --state NEW,ESTABLISHED -j ACCEPT
-A OUTPUT -p tcp --sport $ARG1 -m state --state ESTABLISHED -j ACCEPT

# allow incoming ping
-A INPUT -p icmp --icmp-type echo-request -j ACCEPT
-A OUTPUT -p icmp --icmp-type echo-reply -j ACCEPT

# allow outgoing DNS
-A OUTPUT -p udp --dport 53 -j ACCEPT
-A INPUT -p udp --sport 53 -j ACCEPT

COMMIT