-P INPUT DROP
-P FORWARD DROP
-P OUTPUT DROP
-A INPUT -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
-A INPUT -i lo -j ACCEPT
-A INPUT -p ipv6-icmp -j ACCEPT
-A INPUT -d ff02::fb/128 -p udp -m udp --dport 5353 -j ACCEPT
-A INPUT -p tcp -m tcp --dport 22 -j ACCEPT
-A OUTPUT -m conntrack --ctstate NEW,RELATED,ESTABLISHED -j ACCEPT
-A OUTPUT -o lo -j ACCEPT
-A OUTPUT -p ipv6-icmp -j ACCEPT