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_kA... [3] https://lore.kernel.org/lkml/a69faebb-11e8-b386-d591-dbd08330b008@linux.alib...
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(-)