
justcaptcha
⚡ Professional Velocity anti-bot by JustPlugins! 🛡️ Map-captcha, interactive quests & smart VPN check. 🔗 Works perfectly with LimboAuth / LimboAPI! 🚀
🛡️ ProstoCaptcha (by JustPlugins)
ProstoCaptcha is a professional-grade anti-bot solution for Velocity 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:
- Resource Gathering: High-precision tracking of mining tasks including wood, stone, iron, coal, and diamonds.
- Crafting & Smelting Logic: 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:
- Advanced Rendering: Uses
Graphics2Dwith anti-aliasing and gradient paints to generate unique codes on the fly. - OCR Protection: 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:
- Gravity Analysis: 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:
- External API Support: 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
- Platform: Velocity Proxy (Java 17+)
- Dependencies: LimboAPI (Required).
- Protocol Handling: Custom implementation of
BlockDigPacketandUseItemOnBlockPacketfor low-level action tracking without overhead. - Visuals: Full MiniMessage support for modern hex-gradients in BossBars, Titles, and Chat.
📦 Project Structure
me.prostoac.captcha.protocol: Custom packet decoders for serverbound-only actions, ensuring efficient communication handling.CaptchaSessionHandler: 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.
