I have started looking at Trezor Safe 7 as a potential platform on which to implement some custom HSM logic. Specifically, I have seen that you enforce your firmware chain of trust using a vendor header as an intermediate step between bootloader and firmware. I would like to know whether Trezor can issue custom signed vendor headers to developers or companies wanting to build custom firmware on top of your platform. If that was the case, I would assume these headers would include things like delays, red background, user click and/or custom wording and logo ā which would be completely fine for the use case Iām thinking about. Is that a possibility? Also: what would happen to hardware attestation in this case? Would I still be able to attest to firmware running on authentic hardware? Thanks!
can? for sure
Will? Nope.
While this feature was originally designed for this purpose, there are no plans to ever open up vendor headers to 3rd parties.
The vendor headers have flags that allow or disallow access to hardware attestation. So in the event you could get your own vendor header, you could also in theory have it set to not lose attestation.
Unfortunately, the attestation as-is attests to the whole package, so allowing it for a 3rd party is out of the question. But if you were to go that way, you can use the U5ās security features to do your own attestation.
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