From 247a0fc65e5deea58a1486a0e506bc38fd9bed6b Mon Sep 17 00:00:00 2001 From: Min Xu Date: Wed, 4 May 2022 08:13:50 +0800 Subject: [PATCH] OvmfPkg: Add README for TDVF RFC: https://bugzilla.tianocore.org/show_bug.cgi?id=3249 Add README for TDVF. Cc: Brijesh Singh Cc: Erdem Aktas Cc: Gerd Hoffmann Cc: James Bottomley Cc: Jiewen Yao Cc: Tom Lendacky Signed-off-by: Min Xu Acked-by: Gerd Hoffmann Reviewed-by: Jiewen Yao --- 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 0000000000..cc01ebca5c --- /dev/null +++ b/OvmfPkg/IntelTdx/README @@ -0,0 +1,88 @@ +TDVF Overview +------------- + +Intel Trust Domain Extension (TDX) is Intel Architecture extension +to provide trusted, isolated VM execution by removing CSP software +(hypervisor etc) from the TCB. TDX Virtual Firmware (TDVF) is an +EDK II based project to enable UEFI support for TDX based Virtual +Machines. It provides the capability to launch a TD. + +The Intel? TDX Virtual Firmware Design Guide 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. + +Config-A: + - 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. + +Config-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, Config-A has been merged into edk2-master branch. +The corresponding pkg file is OvmfPkg/OvmfPkgX64.dsc. + +Config-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. -- 2.39.2