iptables -A INPUT -p tcp --destination-port 22 -j ACCEPT
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A INPUT -p udp --destination-port 5353 -d 224.0.0.251 -j ACCEPT 
iptables -A INPUT -i lo -j ACCEPT
iptables -P INPUT DROP
iptables -P FORWARD DROP