PHP script to execute iptables command

I'm trying to get a web-accessible .php page to trigger an iptables command (which requires root privileges). The php page has one line: exec('sudo iptables -I INPUT 3 -s [login to view URL] -p tcp --destination-port 443 -j DROP'); I used visudo to modify /etc/[login to view URL] I have two questions that you're bidding on: QUESTION 1) Which is the correct format for the [login to view URL] file: www-data ALL=(ALL:ALL) NOPASSWD: /sbin/iptables www-data ALL = NOPASSWD: /sbin/iptables www-data ALL=(ALL) NOPASSWD: /sbin/iptables QUESTION 2) Is there a better way to do this? Should I not be allowing www-data to run iptables? The only command I need to run is "iptables -I INPUT...-j DROP" Please post your bid for answering both questions. And if #2 is "yes", for explaining what to do. Thanks for reading!