Re: [PATCH v9 2/2] tpm: Add support for event log pointer found in TPM2 ACPI table

From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To: Stefan Berger <stefanb@linux.ibm.com>
Cc: Stefan Berger <stefanb@linux.vnet.ibm.com>,
	linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-acpi@vger.kernel.org,
	linux-security-module@vger.kernel.org
Subject: Re: [PATCH v9 2/2] tpm: Add support for event log pointer found in TPM2 ACPI table
Date: Wed, 8 Jul 2020 17:07:53 +0300	[thread overview]
Message-ID: <20200708140753.GC538949@linux.intel.com> (raw)
In-Reply-To: <85c27199-df55-eecc-855c-dedcea64f89e@linux.ibm.com>

On Tue, Jul 07, 2020 at 12:09:11AM -0400, Stefan Berger wrote:
> On 7/7/20 12:03 AM, Jarkko Sakkinen wrote:
> > On Mon, Jul 06, 2020 at 11:08:12PM -0400, Stefan Berger wrote:
> > > On 7/6/20 10:24 PM, Jarkko Sakkinen wrote:
> > > > On Mon, Jul 06, 2020 at 07:55:26PM -0400, Stefan Berger wrote:
> > > > > On 7/6/20 7:09 PM, Jarkko Sakkinen wrote:
> > > > > > On Mon, Jul 06, 2020 at 02:19:53PM -0400, Stefan Berger wrote:
> > > > > > > From: Stefan Berger <stefanb@linux.ibm.com>
> > > > > > > 
> > > > > > > In case a TPM2 is attached, search for a TPM2 ACPI table when trying
> > > > > > > to get the event log from ACPI. If one is found, use it to get the
> > > > > > > start and length of the log area. This allows non-UEFI systems, such
> > > > > > > as SeaBIOS, to pass an event log when using a TPM2.
> > > > > > > 
> > > > > > > Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
> > > > > > Do you think that QEMU with TPM 1.2 emulator turned on would be a viable
> > > > > > way to test this?
> > > > > Yes.
> > > > Is the emulator bundled with QEMU or does it have to be installed
> > > > separately?
> > > It has to be installed separately. On Fedora 31 it would just be a `sudo dnf
> > > -y install swtpm-tools` and you should be good to go with libvirt /
> > > virt-manager.
> > Is there some packaging for Debian/Ubuntu available?
> 
> 
> So far may not be available yet. I had *experimented* with a PPA once:
> https://launchpad.net/~stefanberger/+archive/ubuntu/swtpm-focal

There is a snap available:

name:      swtpm-mvo
summary:   Libtpms-based TPM emulator
publisher: Michael Vogt (mvo)
store-url: https://snapcraft.io/swtpm-mvo
license:   unset
description: |
  Libtpms-based TPM emulator with socket, character device, and Linux
  CUSE interface.
commands:
  - swtpm-mvo.swtpm
services:
  swtpm-mvo.swtpm-sock: simple, enabled, active
snap-id:      HNl1TwHRBk3OtXQ8OriRB93FDZ6vman7
tracking:     latest/edge
refresh-date: today at 02:05 EEST
channels:
  latest/stable:    –                         
  latest/candidate: –                         
  latest/beta:      0.1.0 2019-07-26 (11) 3MB -
  latest/edge:      0.1.0 2020-07-08 (75) 3MB -
installed:          0.1.0            (74) 3MB -

This is the version information:

❯ swtpm-mvo.swtpm --version
TPM emulator version 0.4.0, Copyright (c) 2014 IBM Corp.

However, if I try to run the first example from [*], I get:

❯ swtpm-mvo.swtpm socket --tpmstate dir=/tmp/mytpm1 \
  --ctrl type=unixio,path=/tmp/mytpm1/swtpm-sock \
  --log level=20
swtpm: Could not open UnixIO socket: No such file or directory

[*] https://www.qemu.org/docs/master/specs/tpm.html

/Jarkko