Re: [RFD] linux-firmware key arrangement for firmware signing

David Howells
2015-05-26T23:07:22Z

One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> wrote:

> Ie you need to sign something more than the firmware, such as (firmware,
> modinfo), so it's signed for "firmware X on PCI:8086,1114 or "firmware Y
> on ACPI:0A1D"

I'm suggesting that we use the name string passed to request_firmware().

> IMHO we want the supplier of a given firmware providing signatures on
> the firmware git tree if this is done. A generic linux-firmware owned key
> would be both a horrendously inviting attack target, and a single point of
> failure.
>
> Git can already do all the needed commit signing bits unless I'm missing
> something here ?

How does this help the kernel check that it's been given the right firmware
blob for its request? Unless you compile into the kernel a list of hashes
compiled from the linux-firmware git head (or representative root hash) - in
which case we're back to Andy's hash list/hash tree approach with the problems
that that entails.

David