HOSTNAME CATCHER

Hostname Catcher is a lightweight Fabric Mod for Dedicated Servers. In this mod you can set a list of allowed hostnames to use when joining your server.

This mod is perfect for any server owner that wants to ensure players joins using the right hostname to their server and avoid random people joining via server scanners.

When such whitelist is empty, your server will still log what kind of hostnames or even your server IP address is used by your player base to join.

Dependencies

This mod only depends on the Fabric API

Installation

1. Stop your server
2. Download the mod and place it in your mods folder along side with Fabric API.
3. Start your server to generate the default config file.
4. Edit the file and restart your server.

Default Configuration File (config.yml )

# Listed domains are allowed to connect, other requests will be blocked.
# If the whitelist is empty, then any connection will be allowed.
# Wildcard supported.
allowed-domains:
  - localhost
  - 127.0.0.1
  - *.example.com

How it works

Case 1: Whitelisted hostnames/domains

When your config file looks like this:

allowed-domains:
  - mc.server.com
  - server.com

When Player_A joins using any of those hostnames, they will join. When Player_B tries to join using your server IP address like "192.168.5.64" instead of such whitelisted hostnames, they will get disconnected.

Case 2: Empty whitelist

When allowed-domains is empty, any user will be able to join using any hostname or the ip address, but the server will show what hostname used a player.