indiv
indiv

Reputation: 17866

Certificates for SSL-enabled embedded systems

I have an embedded system that I expect to be in use for the next 15 years or so, and it has an https-based administration console. From what I understand:

Is there any way to have a long-life certificate so browsers won't complain, or is it necessary to release new firmware every time the certificate expires over the life of the product? Or provide a way for the users to load a new certificate?

Upvotes: 13

Views: 4314

Answers (2)

President James K. Polk
President James K. Polk

Reputation: 42010

This could be one of the rare cases where a self-signed certificate is the correct approach. How many people will need to administer the box? I would think few, and part of the deployment of the box would be to have the certificate installed into the truststore of the administrator's browser.

Upvotes: 4

Paul McMillan
Paul McMillan

Reputation: 20117

Geotrust issues certs for up to 6 years.

I would probably build a firmware update mechanism in anyway in case your issuer (or someone along the line) is compromised and gets added to the Certificate Revocation List.

Is your device expected to be connected to the internet? Building a re-issue process so that it can get a new, trusted cert every few years via the network shouldn't be too hard.

If your security model would allow you to use a self-signed cert, have you considered why you are encrypting the communication at all? A non-trusted cert (and teaching users to ignore the warning) is as bad (or worse) than no encryption at all in many cases.

As an aside, I really hope you're not planning on rolling out the exact same cert to every device you construct. If so, and you have a download process that makes the cert available to the general public via firmware updates, you're back to square 1 of having communications easily spoofed.

Upvotes: 2

Related Questions