From: Dan Williams <dan.j.williams@intel.com>
To: Tom Lendacky <thomas.lendacky@amd.com>,
Dan Williams <dan.j.williams@intel.com>,
<linux-coco@lists.linux.dev>
Cc: Borislav Petkov <bp@alien8.de>,
Dionna Glaze <dionnaglaze@google.com>,
Brijesh Singh <brijesh.singh@amd.com>,
Jeremi Piotrowski <jpiotrowski@linux.microsoft.com>,
Kuppuswamy Sathyanarayanan
<sathyanarayanan.kuppuswamy@linux.intel.com>,
<peterz@infradead.org>, <dave.hansen@linux.intel.com>
Subject: Re: [PATCH v6 6/7] virt: sevguest: Add TSM_REPORTS support for SNP_GET_EXT_REPORT
Date: Fri, 13 Oct 2023 21:46:51 -0700 [thread overview]
Message-ID: <652a1d3b68ca4_f879294c3@dwillia2-mobl3.amr.corp.intel.com.notmuch> (raw)
In-Reply-To: <4778317a-af55-40a6-912c-cc685cb431d9@amd.com>
Tom Lendacky wrote:
> On 10/12/23 21:14, Dan Williams wrote:
> > The sevguest driver was a first mover in the confidential computing
> > space. As a first mover that afforded some leeway to build the driver
> > without concern for common infrastructure.
> >
> > Now that sevguest is no longer a singleton [1] the common operation of
> > building and transmitting attestation report blobs can / should be made
> > common. In this model the so called "TSM-provider" implementations can
> > share a common envelope ABI even if the contents of that envelope remain
> > vendor-specific. When / if the industry agrees on an attestation record
> > format, that definition can also fit in the same ABI. In the meantime
> > the kernel's maintenance burden is reduced and collaboration on the
> > commons is increased.
> >
> > Convert sevguest to use CONFIG_TSM_REPORTS to retrieve the data that
> > the SNP_GET_EXT_REPORT ioctl produces. An example flow follows for
> > retrieving the report blob via the TSM interface utility,
> > assuming no nonce and VMPL==2:
> >
> > report=/sys/kernel/config/tsm/report/report0
> > mkdir $report
> > echo 2 > $report/privlevel
> > dd if=/dev/urandom bs=64 count=1 > $report/inblob
> > hexdump -C $report/outblob # SNP report
> > hexdump -C $report/auxblob # cert_table
> > rmdir $report
> >
> > Given that the platform implementation is free to return empty
> > certificate data if none is available it lets configfs-tsm be simplified
> > as it only needs to worry about wrapping SNP_GET_EXT_REPORT, and leave
> > SNP_GET_REPORT alone.
> >
> > The old ioctls can be lazily deprecated, the main motivation of this
> > effort is to stop the proliferation of new ioctls, and to increase
> > cross-vendor collaboration.
>
> Everything looks good.
I appreciate the help here, thank you.
> As for deprecating the ioctl(), you will probably only be able to
> deprecate the certificate related portions of it. If we ever have a
> common key derivation interface, then the complete ioctl() could be
> deprecated.
Yes, lets cross that bridge when/if another implementation develops a
derived-key retrieval facility. It feels like the unified ABI approach
there wants to be wrapped by trusted-keys. I recall James had thoughts
about that relative to vTPM, and whether vTPM supersedes this facility.
next prev parent reply other threads:[~2023-10-14 4:47 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-10-13 2:13 [PATCH v6 0/7] configfs-tsm: Attestation Report ABI Dan Williams
2023-10-13 2:14 ` [PATCH v6 1/7] virt: sevguest: Fix passing a stack buffer as a scatterlist target Dan Williams
2023-10-13 2:14 ` [PATCH v6 2/7] virt: coco: Add a coco/Makefile and coco/Kconfig Dan Williams
2023-10-13 2:14 ` [PATCH v6 3/7] configfs-tsm: Introduce a shared ABI for attestation reports Dan Williams
2023-10-13 4:43 ` Dionna Amalie Glaze
2023-10-13 5:15 ` Dan Williams
2023-10-16 6:36 ` Alexey Kardashevskiy
2023-10-17 2:19 ` Dan Williams
2023-10-17 6:20 ` Alexey Kardashevskiy
2023-10-19 1:29 ` Dan Williams
2023-10-19 20:24 ` Dan Williams
2023-10-13 2:14 ` [PATCH v6 4/7] virt: sevguest: Prep for kernel internal get_ext_report() Dan Williams
2023-10-13 2:14 ` [PATCH v6 5/7] mm/slab: Add __free() support for kvfree Dan Williams
2023-10-13 2:14 ` [PATCH v6 6/7] virt: sevguest: Add TSM_REPORTS support for SNP_GET_EXT_REPORT Dan Williams
2023-10-13 15:38 ` Tom Lendacky
2023-10-14 4:46 ` Dan Williams [this message]
2023-10-16 11:36 ` Alexey Kardashevskiy
2023-10-16 15:39 ` Dionna Amalie Glaze
2023-10-16 15:42 ` Peter Gonda
2023-10-17 0:42 ` Alexey Kardashevskiy
2023-10-19 4:30 ` Dan Williams
2023-10-17 4:07 ` Dan Williams
2023-10-17 5:35 ` Alexey Kardashevskiy
2023-10-17 6:28 ` Alexey Kardashevskiy
2023-10-19 4:43 ` Dan Williams
2023-10-19 5:12 ` Alexey Kardashevskiy
2023-10-19 3:34 ` Dan Williams
2023-10-13 2:14 ` [PATCH v6 7/7] virt: tdx-guest: Add Quote generation support using TSM_REPORTS Dan Williams
2023-10-19 18:12 ` Peter Gonda
2023-10-13 15:39 ` [PATCH v6 0/7] configfs-tsm: Attestation Report ABI Tom Lendacky
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=652a1d3b68ca4_f879294c3@dwillia2-mobl3.amr.corp.intel.com.notmuch \
--to=dan.j.williams@intel.com \
--cc=bp@alien8.de \
--cc=brijesh.singh@amd.com \
--cc=dave.hansen@linux.intel.com \
--cc=dionnaglaze@google.com \
--cc=jpiotrowski@linux.microsoft.com \
--cc=linux-coco@lists.linux.dev \
--cc=peterz@infradead.org \
--cc=sathyanarayanan.kuppuswamy@linux.intel.com \
--cc=thomas.lendacky@amd.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox