iptables block port on linux

this is my iptables now iptables -t nat -F iptables --table nat --append POSTROUTING -j MASQUERADE sysctl -w net.ipv4.ip_forward=1 iptables -t nat -A PREROUTING -p tcp -d [login to view URL] --dport 2013 -j DNAT --to-destination [login to view URL] so if any one hit [login to view URL] FWD to [login to view URL] but i want to block this for everyone i want to allow only 1IP other every one DROP i try too many way but fail need a expert who can do it you have to work on teamview or if you can test on ur end send me code i will check if work i will pay to check live on my system u need to come teamview dont ask me before test for award if you can do please bid