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Date:   Wed, 28 Jun 2023 08:46:08 +0200
From:   "gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>
To:     "Huang, Kai" <kai.huang@intel.com>
Cc:     "Williams, Dan J" <dan.j.williams@intel.com>,
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Subject: Re: [PATCH v3 3/3] selftests/tdx: Test GetQuote TDX attestation
 feature
Message-ID: <2023062805-drove-privatize-ae2c@gregkh>
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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