Re: [PATCH V2 1/1] OvmfPkg: Add README for TDVF

["Yao, Jiewen" <jiewen.yao@intel.com>]

Reviewed-by: Jiewen Yao <Jiewen.yao@intel.com>

> -----Original Message-----
> From: Xu, Min M <min.m.xu@intel.com>
> Sent: Wednesday, May 4, 2022 8:14 AM
> To: devel@edk2.groups.io
> Cc: Xu, Min M <min.m.xu@intel.com>; Brijesh Singh <brijesh.singh@amd.com>;
> Aktas, Erdem <erdemaktas@google.com>; Gerd Hoffmann
> <kraxel@redhat.com>; James Bottomley <jejb@linux.ibm.com>; Yao, Jiewen
> <jiewen.yao@intel.com>; Tom Lendacky <thomas.lendacky@amd.com>
> Subject: [PATCH V2 1/1] OvmfPkg: Add README for TDVF
> 
> RFC: https://bugzilla.tianocore.org/show_bug.cgi?id=3249
> 
> Add README for TDVF.
> 
> Cc: Brijesh Singh <brijesh.singh@amd.com>
> Cc: Erdem Aktas <erdemaktas@google.com>
> Cc: Gerd Hoffmann <kraxel@redhat.com>
> Cc: James Bottomley <jejb@linux.ibm.com>
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Tom Lendacky <thomas.lendacky@amd.com>
> Signed-off-by: Min Xu <min.m.xu@intel.com>
> ---
>  OvmfPkg/IntelTdx/README | 88
> +++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 88 insertions(+)
>  create mode 100644 OvmfPkg/IntelTdx/README
> 
> diff --git a/OvmfPkg/IntelTdx/README b/OvmfPkg/IntelTdx/README
> new file mode 100644
> index 000000000000..20426a4f0bf8
> --- /dev/null
> +++ b/OvmfPkg/IntelTdx/README
> @@ -0,0 +1,88 @@
> +TDVF Overview
> +-------------
> +
> +<b>Intel Trust Domain Extension (TDX)</b> is Intel Architecture extension
> +to provide trusted, isolated VM execution by removing CSP software
> +(hypervisor etc) from the TCB. <b>TDX Virtual Firmware (TDVF)</b> is an
> +EDK II based project to enable UEFI support for TDX based Virtual
> +Machines. It provides the capability to launch a TD.
> +
> +The <b>Intel® TDX Virtual Firmware Design Guide</b> is at
> +https://www.intel.com/content/dam/develop/external/us/en/documents/tdx-
> virtual-firmware-design-guide-rev-1.01.pdf.
> +
> +More information can be found at:
> +https://www.intel.com/content/www/us/en/developer/articles/technical/intel
> -trust-domain-extensions.html
> +
> +
> +Configurations and Features
> +----------------------------
> +
> +There are 2 configurations for TDVF.
> +
> +<b>Config-A:</b>
> + - Merge the *basic* TDVF feature to existing OvmfX64Pkg.dsc. (Align
> +   with existing SEV)
> + - Threat model: VMM is NOT out of TCB. (We don’t make things worse)
> + - The OvmfX64Pkg.dsc includes SEV/TDX/normal OVMF basic boot capability.
> +   The final binary can run on SEV/TDX/normal OVMF.
> + - No changes to existing OvmfPkgX64 image layout.
> + - No need to add additional security features if they do not exist today.
> + - No need to remove features if they exist today.
> + - RTMR is not supported.
> + - PEI phase is NOT skipped in either Td or Non-Td.
> +
> +<b>Config-B:</b>
> + - (*) Add a standalone IntelTdx.dsc to a TDX specific directory for a *full*
> +   feature TDVF.(Align with existing SEV)
> + - (*) Threat model: VMM is out of TCB. (We need necessary change to prevent
> +   attack from VMM)
> + - (*) IntelTdx.dsc includes TDX/normal OVMF basic boot capability. The final
> +   binary can run on TDX/normal OVMF.
> + - It might eventually merge with AmdSev.dsc, but NOT at this point of
> +   time. And we don’t know when it will happen. We need sync with AMD in
> +   the community after both of us think the solutions are mature to merge.
> + - Need to add necessary security feature as mandatory requirement, such
> +   as RTMR based Trusted Boot support.
> + - Need to measure the external input from Host VMM, such as TdHob, CFV.
> + - Need to measure other external input, such as FW_CFG data, os loader,
> +   initrd, etc.
> + - Need to remove unnecessary attack surfaces, such as network stack.
> +
> +In current stage, <b>Config-A</b> has been merged into edk2-master branch.
> +The corresponding pkg file is OvmfPkg/OvmfPkgX64.dsc.
> +
> +<b>Config-B</b> is split into several waves. The corresponding pkg file is
> +OvmfPkg/IntelTdx/IntelTdxX64.dsc. The features with (*) have been
> implemented
> +and merged into edk2-master branch. Others are in upstreaming progress.
> +
> +Build
> +------
> +- Build the TDVF (Config-A) target:
> +`cd /path/to/edk2`
> +`source edksetup.sh`
> +`build.sh -p OvmfPkg/OvmfPkgX64.dsc -a X64 -t GCC5`
> +
> +- Build the TDVF (Config-B) target:
> +`cd /path/to/edk2`
> +`set PACKAGES_PATH=/path/to/edk2/OvmfPkg`
> +`source edksetup.sh`
> +`build.sh -p OvmfPkg/IntelTdx/IntelTdxX64.dsc -a X64 -t GCC5`
> +
> +Usage
> +-----
> +
> +Assuming TDX-QEMU/TDX-KVM are already built, one can start a TD virtual
> +machine as [launching-td-guest](https://github.com/intel/qemu-tdx/blob/tdx-
> qemu-upstream-rfc-v3/docs/system/i386/tdx.rst#launching-a-td-tdx-vm):
> +
> +`qemu_system_x86 \`
> +`   -machine ...,confidential-guest-support=tdx0 \`
> +`   -object tdx-guest,id=tdx0,[sept-ve-disable=off] \`
> +`   -drive if=pflash,format=raw,unit=0,file=/path/to/OVMF_CODE.fd \`
> +`   -drive if=pflash,format=raw,unit=1,file=/path/to/OVMF_VARS.fd \`
> +
> +Note:
> +TDX-QEMU/TDX-KVM are still in upstreaming progress. Please refer to:
> + - kvm  : https://github.com/intel/tdx/tree/kvm-upstream
> + - qemu : https://github.com/intel/qemu-tdx/blob/tdx-qemu-upstream-rfc-v3
> +
> +Once above 2 upstreaming are completed a minimum qemu/kvm version will
> be updated here.
> --
> 2.29.2.windows.2