[PATCH v2 0/3] TDX Guest Quote generation support

From: Kuppuswamy Sathyanarayanan
Date: Wed Apr 12 2023 - 23:42:12 EST


Hi All,

In TDX guest, the attestation process is used to verify the TDX guest
trustworthiness to other entities before provisioning secrets to the
guest.

The TDX guest attestation process consists of two steps:

1. TDREPORT generation
2. Quote generation.

The First step (TDREPORT generation) involves getting the TDX guest
measurement data in the format of TDREPORT which is further used to
validate the authenticity of the TDX guest. The second step involves
sending the TDREPORT to a Quoting Enclave (QE) server to generate a
remotely verifiable Quote. TDREPORT by design can only be verified on
the local platform. To support remote verification of the TDREPORT,
TDX leverages Intel SGX Quoting Enclave to verify the TDREPORT
locally and convert it to a remotely verifiable Quote. Although
attestation software can use communication methods like TCP/IP or
vsock to send the TDREPORT to QE, not all platforms support these
communication models. So TDX GHCI specification [1] defines a method
for Quote generation via hypercalls. Please check the discussion from
Google [2] and Alibaba [3] which clarifies the need for hypercall based
Quote generation support. This patch set adds this support.

Support for TDREPORT generation already exists in the TDX guest driver.
This patchset extends the same driver to add the Quote generation
support.

Following are the details of the patch set:

Patch 1/3 -> Adds event notification IRQ support.
Patch 2/3 -> Adds Quote generation support.
Patch 3/3 -> Adds selftest support for Quote generation feature.

[1] https://cdrdv2.intel.com/v1/dl/getContent/726790, section titled "TDG.VP.VMCALL<GetQuote>".
[2] https://lore.kernel.org/lkml/CAAYXXYxxs2zy_978GJDwKfX5Hud503gPc8=1kQ-+JwG_kA79mg@xxxxxxxxxxxxxx/
[3] https://lore.kernel.org/lkml/a69faebb-11e8-b386-d591-dbd08330b008@xxxxxxxxxxxxxxxxx/

Kuppuswamy Sathyanarayanan (3):
x86/tdx: Add TDX Guest event notify interrupt support
virt: tdx-guest: Add Quote generation support
selftests/tdx: Test GetQuote TDX attestation feature

Documentation/virt/coco/tdx-guest.rst | 11 ++
arch/x86/coco/tdx/tdx.c | 196 +++++++++++++++++++
arch/x86/include/asm/tdx.h | 8 +
drivers/virt/coco/tdx-guest/tdx-guest.c | 168 +++++++++++++++-
include/uapi/linux/tdx-guest.h | 43 ++++
tools/testing/selftests/tdx/tdx_guest_test.c | 68 ++++++-
6 files changed, 487 insertions(+), 7 deletions(-)

--
2.34.1