[kfreds]

> .. I wish there was some sort of black box mechanism for logging certain events in such a way that the device itself can't tamper with it..

This is called an append-only log. It can be built in many ways. Which way is suitable largely depends on the security requirements.

My personal favorite kind of append-only logging is transparency logging. If you'd like to learn more you can check out e.g. sigsum.org, an open-source project my colleagues and I have been working on for several years now.