Re: [PATCH v1 0/3] TDX Guest Quote generation support

From: Dionna Amalie Glaze
Date: Tue Mar 28 2023 - 16:00:45 EST


+Chong Cai

Adding a colleague per his request since he's not subscribed to the list yet.

On Mon, Mar 27, 2023 at 10:36 AM Erdem Aktas <erdemaktas@xxxxxxxxxx> wrote:
>
> On Sat, Mar 25, 2023 at 11:20 PM Kuppuswamy Sathyanarayanan
> <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> wrote:
> >
> > 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
> Thanks Sathyanarayanan for submitting patches again.
>
> I just wanted to reiterate what I said before that having a clean
> TDVMCALL based interface to get TDX Quote without any virtio/vsock
> dependency is critical for us to support many use cases.



--
-Dionna Glaze, PhD (she/her)