I just read through the MS docs on SecureBoot and this is the biggest Rube-Goldberg
machine.
I could not think of a nastier solution to a problem than what they've dreamt up
here.
The whole problem they are trying to solve is that of booting only known-good code.
That would be much easier accomplished by having the OS reside on a read-only device that
could only be written to by
the user actively using hardware to enable the write during installation.
That would create a system where there was no possible programmatic means of corrupting
the OS during normal operation.
No signatures, no crypto-databases, or other SecureBoot gobbledy-gook needed.
To implement this would require only that new systems support two drives, one with
controllable-by-user
read-write-controller interface for storing the OS.
Forensic firms have been using these types of read-write controllable drive interfaces for
years. Hardware already exists.
.