RE: [PATCH 0/2] efi: Enhance capsule loader to support signed Quark images

From: Kweh, Hock Leong
Date: Fri Feb 17 2017 - 03:23:59 EST


> -----Original Message-----
> From: Bryan O'Donoghue [mailto:pure.logic@xxxxxxxxxxxxxxxxx]
> Sent: Friday, February 17, 2017 8:54 AM
> To: Kweh, Hock Leong <hock.leong.kweh@xxxxxxxxx>; Jan Kiszka
> <jan.kiszka@xxxxxxxxxxx>; Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> Cc: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx>; Ard Biesheuvel
> <ard.biesheuvel@xxxxxxxxxx>; linux-efi@xxxxxxxxxxxxxxx; Linux Kernel Mailing
> List <linux-kernel@xxxxxxxxxxxxxxx>; Borislav Petkov <bp@xxxxxxxxx>
> Subject: Re: [PATCH 0/2] efi: Enhance capsule loader to support signed Quark
> images
>
>
>
> On 16/02/17 03:00, Kweh, Hock Leong wrote:
> >> -----Original Message-----
> >> From: Jan Kiszka [mailto:jan.kiszka@xxxxxxxxxxx]
> >> Sent: Thursday, February 16, 2017 3:00 AM
> >> To: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> >> Cc: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx>; Ard Biesheuvel
> >> <ard.biesheuvel@xxxxxxxxxx>; linux-efi@xxxxxxxxxxxxxxx; Linux Kernel
> >> Mailing List <linux-kernel@xxxxxxxxxxxxxxx>; Borislav Petkov
> >> <bp@xxxxxxxxx>; Kweh, Hock Leong <hock.leong.kweh@xxxxxxxxx>; Bryan
> >> O'Donoghue <pure.logic@xxxxxxxxxxxxxxxxx>
> >> Subject: Re: [PATCH 0/2] efi: Enhance capsule loader to support
> >> signed Quark images
> >>
> >> On 2017-02-15 19:50, Jan Kiszka wrote:
> >>> On 2017-02-15 19:46, Andy Shevchenko wrote:
> >>>> On Wed, Feb 15, 2017 at 8:14 PM, Jan Kiszka
> >>>> <jan.kiszka@xxxxxxxxxxx>
> >> wrote:
> >>>>> See patch 2 for the background.
> >>>>>
> >>>>> Series has been tested on the Galileo Gen2, to exclude
> >>>>> regressions, with a firmware.cap without security header and the
> >>>>> SIMATIC IOT2040 which requires the header because of its mandatory
> secure boot.
> >>>>
> >>>> Briefly looking to the code it looks like a real hack.
> >>>> Sorry, but it would be carefully (re-)designed.
> >>>
> >>> The interface that the firmware provides us? That should have been
> >>> done differently, I agree, but I'm not too much into those firmware
> >>> details, specifically when it comes to signatures.
> >>>
> >>> The Linux code was designed around that suboptimal situation. If
> >>> there are better ideas, I'm all ears.
> >>>
> >>
> >> Expanding CC's as requested by Andy.
> >>
> >> Jan
> >>
> >
> > Hi Jan,
> >
> > While I upstreaming the capsule loader patches, I did work with
> > maintainer Matt and look into this security header created for Quark.
> > Eventually both of us agreed that this will not be upstream to
> > mainline as it is really a Quark specific implementation.
>
> What's the logic of that ?
>
> It should be possible to provide a hook (or a custom function).
>
> >
> > The proper implementation may require to work with UEFI community to
> > expand its capsule spec to support signed binary.
>
> Are you volunteering to do that with - getting the CSH into the UEFI spec ?
>
> If not then we should have a method to load/ignore a capsule including the CSH,
> if so then we should have a realistic timeline laid out for getting that spec work
> done.
>
> Hint: I don't believe integrating the CSH into the UEFI standard will happen...
>

Hi Jan & Bryan,

Please don't get me wrong. I am not rejecting the patch submission.
I am just sharing a summary for the discussion that I had had it a year back
with maintainer Matt for this topic. From the discussion, we did mention
what would be the proper handling to this case. And to have UEFI expand
it capsule support and take in signed binary would be a more secured way.
So, influencing UEFI community to have such support would be the right
move throughout the discussion. That is my summary.

Of course, influencing the UEFI community would be the longer path.
I think it is worth for try to bring the topic up here again to see if Matt
would reconsider it.


Regards,
Wilson