GateKeeper

Overview

GateKeeper is a modern, security-focused authentication plugin designed specifically for Minecraft servers running in offline-mode.

It focuses on reducing account abuse, brute-force attempts, and common authentication bypasses while remaining lightweight and easy to configure.

Features

- Password-based authentication using BCrypt - Full player lockdown before authentication - Per-account rate limiting to reduce brute-force attempts - Automatic account locking after configurable failed login attempts - Staff commands: `/gate lock`, `/gate unlock`, `/gate forcereset`, `/gate info`, `/gate help` - Persistent storage using SQLite - Username filtering to block disallowed names - Authentication teleport system (optional auth spawn and return location) - Sensible defaults with minimal configuration required

Lightweight and Simple

- No proxies required - No external servers or services - No unnecessary dependencies - Designed for long-term, unattended operation

GateKeeper is intended to be installed once and run reliably with minimal maintenance.

Important Notes

GateKeeper is intended for servers running in offline-mode.

This means: - Mojang account ownership cannot be verified - Premium account trust is not automatic - It should not be used on servers running in online-mode

For full account security, it is recommended to: - Enable `online-mode=true`, or - Use a proxy with online authentication

GateKeeper exists to reduce risk on offline-mode servers, not to replace official authentication.

Compatibility

- Paper - Purpur - Pufferfish - Spigot

Philosophy

Offline-mode servers will never be perfectly secure. GateKeeper focuses on risk reduction through strong authentication and sensible security defaults.