iptables - rule to block all other incoming traffic except ssh

I currently have the following rules to allow connections to my SSH server on port 2233:

iptables -A INPUT -p tcp --dport 2233 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
iptables -A OUTPUT -p tcp --sport 2233 -m conntrack --ctstate ESTABLISHED -j ACCEPT

However, I now need to write a rule that blocks all other incoming traffic apart from the incoming traffic to the SSH on port 2233. I also need to enable logging for all other blocked traffic to be labelled as "BLOCKED TRAFFIC >"

Any help would be greatly appreciated. Thanks!

1 Answer

Just append this:

iptables -A INPUT -j LOG --log-prefix "BLOCKED TRAFFIC > " --log-level 4
iptables -A INPUT -j DROP

Packets not matched by previous ACCEPTs (or DROPs) will be processed and so get LOGged and then DROPped...