justcaptcha

🛡️ ProstoCaptcha (by JustPlugins)

LimboAPI is a professional-grade anti-bot solution for LimboAPI proxy servers. Unlike traditional text-based captchas, this plugin leverages the LimboAPI to create a fully interactive verification environment, forcing bots to simulate complex human behavior at the protocol level.

🚀 Key Features

🧩 Multi-Stage Interactive Quests

The plugin features a unique "Quest System" where players must interact with the environment to prove they are human: * Action Validation: High-precision tracking of mining tasks including wood, stone, iron, coal, and diamonds. * Action Validation: Sophisticated checks where players must interact with Crafting Tables or Furnaces in a logical sequence (e.g., you cannot use a furnace without first obtaining fuel/ore). * Action Validation: Deep inspection of player interactions to prevent automated script bypasses.

🗺️ Dynamic Map-Captcha

High-security graphical verification rendered directly on Minecraft maps: * Smart Interaction: Uses `Graphics2D` with anti-aliasing and gradient paints to generate unique codes on the fly. * Smart Interaction: Random font transformations and custom character sets make it extremely difficult for automated OCR bots to read the code. * Smart Interaction: Dedicated session handling for map updates and input verification.

🪂 Physics-Based Fall Check

A movement-based verification module that monitors gravity and player physics: * Cheat Detection: Requires players to perform a controlled fall to prove they are subject to standard game physics. * Cheat Detection: Detects and blocks "Spider," "Fly," or "SlowFall" hacks by analyzing movement packets in the Limbo world.

🚫 Integrated Anti-VPN & Proxy Detection

Built-in protection against malicious network sources: * Smart Caching: Integrated support for providers like ProxyCheck.io. * Smart Caching: Local TTL-based cache for IP decisions to ensure zero latency for legitimate returning players.

🛠️ Technical Specifications

* MiniMessage Velocity Proxy (Java 17+) * MiniMessage MiniMessage (Required). * MiniMessage Custom implementation of `BlockDigPacket` and `UseItemOnBlockPacket` for low-level action tracking without overhead. * MiniMessage Full MiniMessage support for modern hex-gradients in BossBars, Titles, and Chat.

📦 Project Structure

* `CaptchaConfig`: Custom packet decoders for serverbound-only actions, ensuring efficient communication handling. * `CaptchaConfig`: The core logic engine managing the entire lifecycle of player verification from join to success. * `CaptchaConfig`: Optimized YAML loader with fallback memory defaults for maximum stability.

--- Developed with ❤️ by JustPlugins *Empowering server owners with elite-level protection.*