[ Trimming some quoting! ]

On Tue, Jun 04, 2019 at 11:17:09AM -0400, Francois Ozog wrote:
>On Tue, 4 Jun 2019 at 10:57, Ard Biesheuvel <[email protected]>
>>>
>> Yes, that makes sense. But the problem is that UEFI secure boot does not
>> support this model. An image is considered valid if it authenticates
>> against any of the keys in db. And any key in KEK can sign updates to db
>> and dbx. And today's current practice is to include Microsoft keys in both
>> KEK and db.
>>
>> I have argued time and time again that this is entirely broken as a
>> security model. Any db update that Microsoft has ever signed can be applied
>> to my brand new arm64 system (unless it has been blacklisted explicitly,
>> and my vendor has bothered to ship with an up to date dbt)
>>
>> I am perfectly happen to reopen that debate as well, by the way :-)
>>
>Is it correct to say that Msft could revoke selective keys and prevent the
>boot of selected devices?
>If true, in the current geopolitical context, I would assume this is not
>acceptable... and distros may not have the final word here as it may be
>regulatory costrainst or customer requirement.

Technically yes, but actually updating the revocation and blacklists
is quite rare. It would be up to the user (or some user-enabled
software) to take the updates.

Cheers,
-- 
Steve McIntyre                                [email protected]
<http://www.linaro.org/> Linaro.org | Open source software for ARM SoCs

_______________________________________________
boot-architecture mailing list
[email protected]
https://lists.linaro.org/mailman/listinfo/boot-architecture

Reply via email to