NAT and blocking all but Port 22

This is a review of the iptables firewall script that allows for NAT and blocking all but Port 22. The script is simple and easy to install, making it a great option for users looking for basic network security.

The script includes modules such as ip_tables, ip_conntrack, ip_conntrack_ftp, ipt_state, iptable_nat, and ipt_MASQUERADE, which all work together to provide robust security features. The script deletes all rules in the Filtertable and defines new chains for blocking traffic.

The script also includes various chain rules such as BLOCK, EXT-INT, INT-EXT, ICMP-DENY, INT-IF, and EXT-IF to help organize and prioritize traffic. The script allows for established, related, and new traffic, but blocks all other traffic. It also includes point-to-chains rules for input, forward, and output traffic.

The NAT rules in the script include standard routing as well as port forwarding rules. The script also allows for IP-forwarding and enables easy communication between internal and external devices.

Overall, this iptables firewall script is a reliable and easy-to-use option for users looking for basic network security. The various modules, chains, and rules included make it a robust option for home or small office networks.