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

Stefan Berger stefanb at linux.ibm.com
Wed Jul 8 14:17:17 UTC 2020


On 7/8/20 10:07 AM, Jarkko Sakkinen wrote:
> 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 at 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 at 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


Did you create the directory '/tmp/mytpm1' ?


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




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