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Date:   Sat, 20 Feb 2021 05:09:07 +0200
From:   Jarkko Sakkinen <jarkko@kernel.org>
To:     Matthew Garrett <matthewgarrett@google.com>
Cc:     linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org,
        linux-pm@vger.kernel.org, keyrings@vger.kernel.org,
        zohar@linux.ibm.com, jejb@linux.ibm.com, corbet@lwn.net,
        rjw@rjwysocki.net, Matthew Garrett <mjg59@google.com>
Subject: Re: [PATCH 5/9] security: keys: trusted: Allow storage of PCR values
 in creation data
Message-ID: <YDB9U2oyt0fmvLDF@kernel.org>
References: <20210220013255.1083202-1-matthewgarrett@google.com>
 <20210220013255.1083202-6-matthewgarrett@google.com>
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On Sat, Feb 20, 2021 at 01:32:51AM +0000, Matthew Garrett wrote:
> When TPMs generate keys, they can also generate some information
> describing the state of the PCRs at creation time. This data can then
> later be certified by the TPM, allowing verification of the PCR values.
> This allows us to determine the state of the system at the time a key
> was generated. Add an additional argument to the trusted key creation
> options, allowing the user to provide the set of PCRs that should have
> their values incorporated into the creation data.
> 
> Signed-off-by: Matthew Garrett <mjg59@google.com>

LGTM too.

Something popped into mind: could we make PCR 23 reservation dynamic
instead of a config option.

E.g. if the user space uses it, then it's dirty and hibernate will
fail. I really dislike the static compilation time firewall on it.

/Jarkko