wtf is xdp-firewall?

XDP Firewall is a tool that blocks malicious network traffic before it can reach your server, with a particular focus on defending against DDoS attacks. It intercepts internet traffic at the very earliest point possible inside the Linux operating system, which means it can drop bad packets with almost zero delay. It supports both IPv4 and IPv6 networks. Under the hood, it uses a Linux technology called XDP, which lets the system inspect and discard network packets immediately as they arrive at the network card, before the operating system even fully processes them. You configure rules in a text file to tell it what traffic to allow or block, such as specific IP addresses, entire IP ranges, or specific ports. It also tracks traffic volume, so you can set limits on how many packets per second a single IP is allowed to send, and temporarily ban sources that flood your server. The people who would use this are network engineers, security professionals, or anyone running a Linux server that needs to withstand high-volume traffic attacks. For example, a game server operator could use it to block a known attacker's IP address, or to drop any traffic hitting a specific game port that exceeds a safe number of packets per second. It can be managed dynamically, so you can add or remove blocked IPs while the firewall is running without having to restart the service. One notable tradeoff the project makes is keeping the firewall "stateless." Unlike a traditional firewall that tracks the ongoing state of your network connections, this one evaluates each packet on its own merits. This design choice maximizes speed and efficiency, which is critical when absorbing a massive attack, but it means the tool is optimized for blocking and filtering rather than complex traffic routing.