Hello friends,
Just about every guide that comes up on my Google search for "How to create certificate authority with OpenSSL" seems to be out-of-date. Particularly, they all guide me towards creating a certificate that gets rejected by the browser due to the "Common Name" field deprecation, and the requirement of "Subject Alternative Name" field.
Does someone know a tool that creates a Certificate Authority and signs certificates with that CA? A tool that follows modern standards, gets accepted by browsers and other common web tools. Preferably something based on OpenSSL.
If you know a guide that does this using OpenSSL, even better! But I have low hopes for this after going through dozens of guides all having the same issue I mentioned above.
Replies to Some Questions you Might Ask Me
Why not just correct those two fields you mention?
I want to make sure I am doing this right. I don't want to keep running into errors in the future. For example, I actually did try that, and npm CLI rejected my certs without a good explanation (through browser accepts it).
Why not Let's Encrypt?
This is for private services that are only accessible on a private network or VPN
If this is for LAN and VPN only services, why do you need TLS?
TLS still has benefits. Any device on the same network could still compromise the security of the communication without TLS. Examples: random webcam or accessory at your house, a Meta Quest VR headset, or even a compromised smartphone or computer.
Use small step CA (or other ACME tools)
I am not sure I want the added complexity of this. I only have 2 services requiring TLS now, and I don't believe I will need to scale that much. I will have setup a way to consume the ACME server. I am happier with just a tool that spits out the certificates and I manage them that way, instead of a whole service for managing certs.
If I am over estimating the difficulty for this, please correct me.
Would that even work? Pointing my domain to a 192 IP address? I don't see how that would work.
Like the other commenter said, you can use Let's Encrypt without needing to expose anything on your network to the internet. I set it up on my network a couple of weeks ago using this guide; I couldn't get caddy to work with duckdns but it worked with Cloudflare without any trouble.
The article sounds like you could have the A records on a local DNS service like Unbound or Pi-hole instead of public DNS. I guess maybe they just need to be defined somewhere that they'll resolve for your Caddy instance.
After looking at my cloudflare records, it seems I misremembered my setup.