Re: [PATCH v6 4/7] tpm: modify tpm_pcr_read() definition to pass a TPM hash algorithm

From: Mimi Zohar
Date: Thu Dec 06 2018 - 14:49:28 EST


On Wed, 2018-12-05 at 15:31 -0500, Mimi Zohar wrote:
> On Tue, 2018-12-04 at 15:40 -0800, Jarkko Sakkinen wrote:
> > On Tue, Dec 04, 2018 at 09:21:35AM +0100, Roberto Sassu wrote:
> > > Currently the TPM driver allows other kernel subsystems to read only the
> > > SHA1 PCR bank. This patch modifies the parameters of tpm_pcr_read() and
> > > tpm2_pcr_read() to pass a tpm_digest structure, which contains the desired
> > > hash algorithm. Also, since commit 125a22105410 ("tpm: React correctly to
> > > RC_TESTING from TPM 2.0 self tests") removed the call to tpm2_pcr_read(),
> > > the new parameter is expected to be always not NULL.
> > >
> > > Due to the API change, IMA functions have been modified.
> > >
> > > Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
> > > Acked-by: Mimi Zohar <zohar@xxxxxxxxxxxxx>
> >
> > Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> >
> > Mimi, Nayna, can you help with testing this (because of the IMA change)?
>
> It's up & running and the measurement list verifies against the TPM
> PCR. ÂAlthough this system has two algorithms enabled, all of the PCRs
> are allocated for one algorithm and none for the other. ÂI'm still
> looking around for another system with PCR 10 enabled for multiple
> algorithms.

PCRs for sha1 and sha256 algorithms are being updated and the
measurement list verifies against the SHA1 PCR-10.

Roberto, have you added support in ima-evm-utils to validate the other
banks?

Mimi