Js Anti Ddos

# DDoS Protection Proxy 🛡️

A lightweight, high-performance DDoS protection proxy with captcha and Under Attack Mode (UAM) challenges. This proxy sits in front of your origin server and helps protect against automated attacks and excessive traffic.

🌟 Features

• Rate Limiting: Per-IP request tracking and throttling
• Dual Protection Modes:
  • Standard Mode with CAPTCHA challenges
  • Under Attack Mode (UAM) with browser verification (WIP)
• High Performance: Minimal overhead with in-memory tracking
• Easy Integration: Works with any origin server
• Modern UI: Clean, responsive design using Tailwind CSS
• Configurable: Adjustable thresholds and protection modes

🚀 Quick Start

# Clone the repository
git clone https://github.com/denigkt/js-anti-ddos.git

# Install dependencies
cd js-anti-ddos
npm install

# Start the server
npm start

🔧 Configuration

Create a .env file in the root directory:

PORT=3000
ORIGIN_URL=https://your-origin-server.com
RPS_THRESHOLD=10
UAM_MODE=false

Configuration Options

🏗️ Architecture

Protection Flow

Request → Rate Limit Check → Challenge (if needed) → Origin Server

Components

• Rate Limiter: Tracks requests per IP
• Challenge Generator: Creates CAPTCHA or browser challenges
• Proxy Handler: Forwards validated requests to origin
• In-Memory Store: Tracks request counts and validations

💻 Technical Stack

• Runtime: Node.js (v18+)
• Framework: Express.js
• Proxy: http-proxy-middleware
• CAPTCHA: svg-captcha
• UI: Tailwind CSS

📦 Project Structure

js-anti-ddos/
├── config/
│   └── config.js
├── src/
│   ├── middleware/
│   │   └── rateLimiter.js
│   ├── services/
│   │   └── captchaService.js
│   ├── utils/
│   │   └── inMemoryStore.js
│   └── server.js
├── public/
│   ├── css/
│   └── js/
├── views/
│   ├── captcha.html
│   └── uam.html
├── package.json
└── README.md

🔨 Development

# Run in development mode
npm run dev

# Run tests
npm test

# Run with specific config
PORT=4000 RPS_THRESHOLD=5 npm start

🔒 Security Features

1. Rate Limiting

   • Configurable RPS threshold
   • IP-based tracking
   • Automatic challenge triggering

2. CAPTCHA Protection

   • SVG-based CAPTCHA
   • Refresh capability
   • Temporary IP validation after success

3. Under Attack Mode (WIP)

   • Browser behavior validation
   • JavaScript execution verification
   • Extended challenge period

🌐 API Endpoints

Protected Routes

• All requests to your origin server are automatically protected

Internal Endpoints

• GET /captcha - Generate CAPTCHA image
• POST /verify-captcha - Verify CAPTCHA solution
• POST /verify-browser - Browser verification (UAM mode)

📝 Example Usage

// Basic proxy setup
const express = require('express');
const app = express();
const { createProxyMiddleware } = require('http-proxy-middleware');

// Apply DDoS protection
app.use(rateLimiter);

// Proxy requests to origin
app.use('/', createProxyMiddleware({ 
    target: config.ORIGIN_URL,
    changeOrigin: true
}));

⚠️ Production Considerations

1. Memory Management

   • Implement Redis/Memcached for distributed setups
   • Regular cleanup of expired data

2. Security

   • Enable HTTPS
   • Set secure headers
   • Implement request validation
   • Add logging and monitoring

3. Performance

   • Use Node.js clustering
   • Implement caching strategies
   • Monitor memory usage

📋 Requirements

• Node.js >= 18.0.0
• npm >= 7.0.0

📜 License

This project is licensed under the MIT License - see the LICENSE file for details.

🗺️ Roadmap

• Redis/Memcached integration
• Clustering support
• Additional challenge types
• Enhanced browser fingerprinting
• Real-time monitoring dashboard
• WebSocket support

🙏 Acknowledgments

• Express.js
• http-proxy-middleware
• svg-captcha
• Tailwind CSS

📞 Support

For support, please:

1. Check the documentation
2. Open an issue in the GitHub repository
3. Contact the maintainers

Made with ❤️ by @denigkt