How to Secure Your Website with the Open‑Source SafeLine WAF in One Command

1. What Is a WAF?

A Web Application Firewall (WAF) is a security layer that protects websites from attacks such as SQL injection, cross‑site scripting (XSS), cross‑site request forgery (CSRF), server‑side request forgery (SSRF), and WebShell uploads. It typically runs as a reverse‑proxy gateway that inspects incoming traffic and blocks malicious requests.

2. Introducing SafeLine (雷池) WAF

SafeLine is an open‑source community WAF built on top of Nginx as a reverse‑proxy. It offers a friendly web UI and can be used effectively even without deep network‑security expertise. The project is maintained by Chaitin Technology, was open‑sourced in April, and has released 31 versions within four months, attracting over 18,000 site administrators and more than 3,000 GitHub stars.

GitHub: https://github.com/chaitin/safeline

3. Installation and Deployment

SafeLine is deployed via Docker containers and provides a one‑click installation script that automatically pulls images, initializes configuration files, and starts the services.

3.1 One‑Command Installation

bash -c "$(curl -fsSLk https://waf-ce.chaitin.cn/release/latest/setup.sh)"

3.2 Installation by Cloning the Repository

git clone [email protected]:chaitin/safeline.git
cd safeline
bash ./setup.sh

3.3 Installation Success Output

____               __          _       _
 / ___|   __ _  ___ / _| ___  __| | ___ | |_ ___
 \___ \  / _` |/ __| |_ / _ \/ _` |/ _ \| __/ _ \
  ___) | | (_| | (__|  _|  __/ (_| | (_) | ||  __/
 |____/   \__,_|\___|_|  \___|\__,_|\___/ \__\___|

[SafeLine] Script call confirmed normal
[SafeLine] Missing Docker environment
[SafeLine] Auto‑install Docker? (Y/n)
# Executing docker install script, commit: xxx
...
[SafeLine] Installation directory (default '/data/safeline'):
[SafeLine] Directory '/data/safeline' has 47G free (requires at least 5G) – confirm? (Y/n)
[SafeLine] Created installation directory '/data/safeline' successfully
...
[SafeLine] SafeLine WAF community edition installed successfully. Access console at:
[SafeLine] https://0.0.0.0:9443/  # Installation successful

After the script finishes, open the displayed URL in a browser to start using the WAF.

4. Working Principle

SafeLine sits in front of the web server as a reverse proxy. All inbound traffic first passes through SafeLine, where malicious requests are detected and sanitized before being forwarded to the actual server, effectively preventing attacks from reaching the application.

5. Core Capabilities

5.1 Web Attack, CC Attack, and Crawler Protection

The detection engine, named yanshi, uses semantic analysis to recursively decode HTTP parameters, score potential attack code, and identify zero‑day exploits ( 0Day). Integrated IP threat intelligence, client fingerprinting, mouse/keyboard behavior analysis, and rate‑limiting provide robust defense against crawlers, scans, and CC attacks.

5.2 Web Traffic Access Control

Through a visual interface, administrators can configure black‑ and white‑lists based on source IP, URL path, domain, headers, body content, and other criteria.

5.3 Website Resource Identification

SafeLine automatically profiles HTTP traffic to generate API portraits, applying dynamic baselines and predictive analytics to detect anomalous behavior and isolate malicious requests hidden within normal traffic patterns.

6. Final Remarks

SafeLine represents nearly a decade of security research by Chaitin Technology, offering an out‑of‑the‑box, enterprise‑grade firewall with high performance—supporting over 10,000 TPS and adding roughly 1 ms latency.

Plug‑and‑play: single‑command installation with an intuitive UI.

Powerful features: semantic‑analysis‑driven attack detection, IP intelligence, dynamic rate limiting, and advanced modeling.

High performance: built on Nginx, capable of handling 10k+ TPS with millisecond‑level latency.

GitHub: https://github.com/chaitin/safeline