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

Petko Manolov
2015-05-21T05:41:31Z

On 15-05-20 21:41:04, Greg Kroah-Hartman wrote:
> On Wed, May 20, 2015 at 07:46:13PM +0300, Petko Manolov wrote:
> > On 15-05-20 17:24:46, One Thousand Gnomes wrote:
> > >
> > > More to the point why do you want to sign firmware files ? Leaving aside the
> > > fact that someone will produce a device with GPLv3 firmware just to p*ss you
> > > off there's the rather more relevant fact that firmware for devices on a so
> > > called "trusted" platform already have signed firmware.
> >
> > For "trusted" systems one would like to make sure everything that goes in has
> > known provenance. Maybe this was the idea?
>
> If so, then just do what people do today, verify their known valid disk image
> before mounting it and then they know they can trust the data on it to be use
> for whatever (including firmware.) No kernel changes needed, distro support
> is already there for this.

I do agree, the infrastructure is already in place. The project i am working on
has very strict security requirements, quite unlike regular Linux box. I was
pleasantly surprised that it didn't take much kernel hacking to get to the point
where stuff is working to our liking.

> I too don't understand this need to sign something that you don't really know
> what it is from some other company, just to send it to a separate device that
> is going to do whatever it wants with it if it is signed or not.

This is not the point. What you need to know is _where_ the firmware came from,
not _what_ it does once it reach your system. If you don't care about such
things, just ignore the signature. :)

Petko