Re: [PATCH v2 04/10] security: keys: trusted: Allow storage of PCR values in creation data

Evan Green
2022-08-24T17:34:56Z

On Wed, Aug 24, 2022 at 4:56 AM Ben Boeckel <me@benboeckel.net> wrote:
>
> On Tue, Aug 23, 2022 at 15:25:20 -0700, Evan Green wrote:
> > diff --git a/Documentation/security/keys/trusted-encrypted.rst b/Documentation/security/keys/trusted-encrypted.rst
> > index 0bfb4c33974890..dc9e11bb4824da 100644
> > --- a/Documentation/security/keys/trusted-encrypted.rst
> > +++ b/Documentation/security/keys/trusted-encrypted.rst
> > @@ -199,6 +199,10 @@ Usage::
> > policyhandle= handle to an authorization policy session that defines the
> > same policy and with the same hash algorithm as was used to
> > seal the key.
> > + creationpcrs= hex integer representing the set of PCR values to be
> > + included in the PCR creation data. The bit corresponding
> > + to each PCR should be 1 to be included, 0 to be ignored.
> > + TPM2 only.
>
> There's inconsistent whitespace here. Given the context, I suspect the
> tabs should be expanded to spaces.
>
> As for the docs themselves, this might preferrably mention how large
> this is supposed to be. It seems to be limited to 32bits by the code.
> What happens if fewer are provided? More? Will there always be at most
> 32 PCR values? Also, how are the bits interpreted? I presume bit 0 is
> for PCR value 0?

Makes sense, I'll pin down the specification a bit better here and fix
up the spacing.

>
> Thanks for including docs.

Thanks for looking at them!

-Evan