Devices may want to support more than one protocol, and for some devices
(e.g. Unifying peripherals stuck in bootloader mode) you might not even be able
to query for the correct protocol anyway.
Asking the user for the UID mapping isn't working very well, as it requires lots
of manual handholding. It also doesn't work very well when the device vendor
does not actually have a PCI ID or if the vendor has split into two entities.
Just use the OUI address as an additional VendorID and match any of the device
IDs against any of the metadata-supplied values.
To do this mount all ESP partitions and check all the binaries there to see if
they match any entries in the new dbx. If we applied the update when a hash
matched, we would unintentially 'brick' the users machine, as the grub and shim
binaries *have* to be updated first.
This functionality does reimplement the PE hashing functionality found in
sbsigntools and pesign. This was done for 4 main reasons:
* There were some memory safety issues found when fuzzing random binaries
* Executing the tools hundreds of times was a lot of overhead
* Operating from a blob of immutable mmap'd memory is much faster
* We only need a very small amount of functionality from both tools
