Bots: A Threat to Your Golang Web Applications

In the ever-evolving landscape of web development, safeguarding your Golang web application from malicious bots and automated attacks is paramount. One effective technique to combat these threats is by employing rate limiting and IP blocking. Today, we'll delve into creating a middleware solution that takes bot protection to the next level: the jailBotsMiddleware.

The JailBotsMiddleware. Quick Overview

The jailBotsMiddleware is a powerful middleware that empowers developers to proactively defend their applications against malicious bots. It functions by analyzing incoming requests and flagging suspicious behavior, such as excessive requests from a single IP address or requests targeting vulnerable endpoints. Once a bot is identified, the middleware takes decisive action. It temporarily jails the offending IP address, preventing further access to the application. This proactive approach significantly reduces the risk of DDoS attacks, scraping, and other harmful activities.

The JailBotsMiddleware. Key Features and Benefits

The jailBotsMiddleware offers several key features that make it a valuable addition to your application's security arsenal:

- IP Blocking: It effectively blocks malicious IP addresses, preventing further attacks.
- Rate Limiting: It can be configured to limit the number of requests per IP address or per time period.
- URL-Based Filtering: It allows you to identify and block requests targeting specific URLs or patterns.
- Customizable Jail Time: You can set the duration for which an IP address remains jailed, providing flexibility in your security strategy.
- Logging and Monitoring: It logs detailed information about blocked requests, enabling you to analyze attack patterns and refine your security measures.

By incorporating the jailBotsMiddleware into your application stack, you can significantly enhance your website's resilience against automated threats, ensuring a smooth and secure user experience.

The JailBotsMiddleware. Implementation

To implement the jailBotsMiddleware, we first need to establish a caching mechanism to store the jailed IP addresses. A popular choice is using an in-memory cache like Redis or a distributed cache like Memcached.

The middleware intercepts incoming requests, extracts the client's IP address, and checks if it's present in the cache. If the IP is found, the request is immediately rejected. For new requests, the middleware can analyze the request headers, URL, and user-agent to identify potential bot behavior. If suspicious activity is detected, the IP is added to the cache for a specified duration.

Logging plays a crucial role in monitoring the effectiveness of the jailBotsMiddleware. By logging information about blocked requests, suspicious activity, and potential false positives, you can gain valuable insights into the behavior of malicious bots and fine-tune their security strategies. Additionally, logs can be used for forensic analysis in case of security breaches, aiding in incident response and investigation.

type jailBotsMiddleware struct{}

func (j *jailBotsMiddleware) Name() string {
	return "Jail Bots Middleware"
}

func (m *jailBotsMiddleware) Handler(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		uri := r.RequestURI
		ip := utils.IP(r)

		if m.isJailed(ip) {
			w.WriteHeader(http.StatusForbidden)
			responses.HTMLResponse(w, r, "malicious access not allowed (jb)")
			return
		}

		if m.isJailable(uri) {
			m.jail(ip)

			config.Logger.Info("Jailed bot from "+ip+" for 5 minutes",
				slog.String("uri", uri),
				slog.String("ip", ip),
				slog.String("useragent", r.UserAgent()),
			)

			w.WriteHeader(http.StatusForbidden)
			responses.HTMLResponse(w, r, "malicious access not allowed (jb)")
			return
		}

		next.ServeHTTP(w, r)
	})
}

func (m jailBotsMiddleware) isJailed(ip string) bool {
	return config.CacheMemory.Has("jail:" + ip)
}

func (m jailBotsMiddleware) jail(ip string) {
	config.CacheMemory.Set("jail:"+ip, ip, 5*time.Minute)
}

func (m jailBotsMiddleware) isJailable(uri string) bool {
	startsWithList := m.startsWithBlacklistedUriList()
	for i := 0; i < len(startsWithList); i++ {
		if strings.HasPrefix(uri, startsWithList[i]) {
			return true
		}
	}

	containsList := m.containsBlacklistedUriList()

	for i := 0; i < len(containsList); i++ {
		if strings.Contains(uri, containsList[i]) {
			return true
		}
	}

	return false
}

Conclusion

In today's digital age, protecting your web applications from malicious bots is a critical security concern. The JailBotsMiddleware offers a robust and effective solution to mitigate these threats. By understanding its features, benefits, and implementation, you can significantly enhance your application's security posture.

Remember, security is an ongoing process. Stay informed about the latest threats, regularly update your middleware and other security measures, and be vigilant in monitoring your application's logs. By taking these steps, you can ensure the long-term security and reliability of your web applications.