Bot Blocker Middleware

Traefik ForwardAuth middleware for blocking bots and rate limiting requests.

Features

• Rate limiting (60 req/min per IP by default)
• Bot detection via user agent patterns
• Chinese botnet detection (IP + HTTP version + outdated browser combo)
• CIDR subnet blocking for known malicious IP ranges
• Locale scraping detection (auto-bans IPs switching locales rapidly)
• Permanent IP banning with 30-day expiry
• Static assets excluded from rate limiting
• Daily log rotation with summaries
• User-friendly block pages

Quick Start

Docker Compose

services:
  bot-blocker:
    image: ghcr.io/myspeedpuzzling/bot-blocker-middleware:latest
    restart: always
    environment:
      - RATE_LIMIT=60
      - [email protected]
    volumes:
      - ./bot-blocker-logs:/var/log/bot-blocker
    networks:
      - traefik

Traefik Configuration

Add to your dynamic-config.yml:

http:
  middlewares:
    bot-blocker:
      forwardAuth:
        address: "http://bot-blocker:3000"
        trustForwardHeader: true

Apply to a router:

labels:
  - "traefik.http.routers.myapp.middlewares=bot-blocker@file"

Environment Variables

Variable	Default	Description
PORT	3000	Server port
RATE_LIMIT	60	Max requests per window
RATE_WINDOW	60000	Window size in ms (1 min)
LOCALE_THRESHOLD	4	Unique locales to trigger ban
LOCALE_MIN_HITS	3	Min requests per locale
LOCALE_WINDOW	60000	Detection window in ms
BAN_DURATION	2592000000	Ban duration in ms (30 days)
CONTACT_EMAIL	[email protected]	Contact email on block pages
LOG_DIR	/var/log/bot-blocker	Log directory

Adding New Bot Patterns

Edit server.js and add patterns to BLOCKED_BOTS array:

const BLOCKED_BOTS = [
  { pattern: /YourBotName/i, reason: 'Description of why blocked' },
  // ... existing patterns
];

Chinese Botnet Detection

Blocks distributed botnets from Chinese cloud providers (Alibaba, Tencent) that evade per-IP rate limiting by rotating through hundreds of IPs.

Detection methods:

1. CIDR blocklist - Known malicious subnets (43.104.33.0/24, 43.173.168.0/21)
2. Combination detection - Blocks requests matching ALL of:
   • IP starts with 43.
   • HTTP/1.1 protocol (bots don't use HTTP/2)
   • Windows 10 + Chrome 100-139 (outdated versions)
3. Fake iOS detection - Blocks 43.x IPs with ancient iOS 13.2.3 user agents

Locale Scraping Detection

Automatically bans IPs that access multiple locale paths rapidly (e.g., scraping /en/, /de/, /fr/, /es/, /ja/ versions).

Trigger: 4+ unique locales with 3+ requests each within 60 seconds = 30-day ban

Persistence: Banned IPs stored in banned-ips.json (survives restarts)

Log Files

/var/log/bot-blocker/
├── blocked-2025-12-07.log    # Daily JSON logs
├── summary-2025-12-06.txt    # Auto-generated summaries
└── banned-ips.json           # Persistent IP bans

View logs:

docker compose logs bot-blocker
cat ./bot-blocker-logs/blocked-$(date +%Y-%m-%d).log | jq .