Re: [PATCH v3 3/3] selftests/tdx: Test GetQuote TDX attestation feature

From: gregkh@xxxxxxxxxxxxxxxxxxx
Date: Wed Jun 28 2023 - 04:10:40 EST


On Wed, Jun 28, 2023 at 02:16:45AM +0000, Huang, Kai wrote:
> > You really shouldn't be putting attestation validation logic in the
> > kernel.
>
> Agreed. The data blob for remote verification should be just some data blob to
> the kernel. I think the kernel shouldn't even try to understand the data blob
> is for which architecture. From the kernel's perspective, it should be just
> some data blob that the kernel gets from hardware/firmware or whatever embedded
> in the root-of-trust in the hardware after taking some input from usrspace for
> the unique identity of the blob that can be used to, e.g., mitigate replay-
> attack, etc.

Great, then use the common "data blob" api that we have in the kernel
for a very long time now, the "firwmare download" api, or the sysfs
binary file api. Both of them just use the kernel as a pass-through and
do not touch the data at all. No need for crazy custom ioctls and all
that mess :)

thanks,

greg k-h