bannedbook/iptablesutils

This project is a simple tool for setting up port forwarding on a Linux server. Port forwarding lets you take traffic arriving at your server on one port and send it along to another server and port somewhere else. The standout feature here is that if the destination server's address changes over time (common with dynamic DNS setups), the tool automatically updates the forwarding rules for you, so traffic keeps flowing without manual intervention. You run it by downloading and executing a shell script on your server. The script presents a plain text menu: you can add a forwarding rule, delete one, list all your current rules, or view your existing network configuration. When you add a rule, it walks you through the setup step by step. Behind the scenes, it uses a built-in Linux networking tool called iptables to manage the actual traffic routing. This is useful for anyone running a relay or middleman server. For example, if you have a server in one location forwarding traffic to a service running on a home network with a changing IP address, this tool handles the bookkeeping. The README specifically mentions people forwarding traffic for an application called "trojan," noting that the most common issue people hit is related to SSL certificate configuration, and suggests the simplest fix is to have the client skip certificate verification. The project is considered stable and still works fine, but the author now recommends a newer, separate project they built. The newer version uses a more modern Linux networking framework, supports forwarding entire ranges of ports at once, and saves rules to a configuration file so you can back them up. The two projects are not compatible with each other, so you would need to uninstall this one before switching.