GPROX: An ACME DNS Proxy for Google Cloud DNS - Synology

[rioncm]

Hi!

I’m excited to share GPROX, a project I created to address a specific challenge in my home network: automating SSL certificates with DNS challenges for systems using Google Cloud DNS—particularly my Synology NAS devices.

The Problem

Like many of you, I rely on SSL certificates to secure my systems and services. Synology’s built-in certificate management is great for basic setups but lacks support for DNS-based ACME challenges. This limitation is especially frustrating when trying to automate certificates for domains hosted on Google Cloud DNS. The existing dns_acemproxy.sh didn't quite fit my need. Specifically I had no success getting it to work with Google Cloud DNS.

I needed a solution that could:
1. Work seamlessly with Google Cloud DNS.
2. Integrate with the awesome acme.sh tool.
3. Fit neatly into my network’s architecture, running in Docker and behind a reverse proxy.

I built: GPROX

GPROX is a lightweight DNS proxy designed to bridge the gap between Google Cloud DNS and acme.sh. It simplifies the process of managing DNS TXT records for ACME challenges, enabling seamless SSL automation. The entire project was built in about a day with the help of some basic programming skills and a lot of support from AI tools like OpenAI’s ChatGPT.

How GPROX Works

1.	Receives Requests: acme.sh sends requests to GPROX to create or remove DNS TXT records for ACME challenges.
2.      Authenticates the request against a user defined API key and validates the requested domain in defined in the config.
3.	Uses a predefined Google Cloud service account to manage DNS records securely.
4.	Validates and Automates: The TXT records are created and deleted automatically, according to acme.sh direction.

Empowered by AI

I'm a total amateur programmer, I relied heavily on AI for this project. ChatGPT helped me:
• Design the system architecture.
• Write and debug the Flask app powering the proxy.
• Create the acme.sh integration scripts.
• Document everything clearly for future reference.

AI truly felt like a coding sidekick, turning what might have been weeks of work into a one-day sprint.

Why This Matters

It’s free, open-source, and available for anyone who wants to use or adapt it:
• GitHub Repo: GPROX
• Docker Hub: rioncm/gprox

What’s Next?

For now, GPROX meets my needs perfectly, but I’m curious how others might use or extend it. I’ve included configuration examples and documentation in the GitHub repository to make it easy for anyone to get started.

Questions or Feedback?

Have you faced similar challenges with SSL automation? How do you handle DNS challenges for your domains? I’d love to hear your thoughts, ideas, or suggestions for improvement.

Thanks for checking out GPROX, and happy automating! 🚀