BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3275
During the SNP guest launch sequence, a special secrets page needs to be inserted by the VMM. The PSP will populate the page; it will contain the VM Platform Communication Key (VMPCKs) used by the guest to send and receive secure messages to the PSP. The purpose of the secrets page in the SEV-SNP is different from the one used in SEV guests. In SEV, the secrets page contains the guest owner's private data after the remote attestation. Cc: Michael Roth <[email protected]> Cc: James Bottomley <[email protected]> Cc: Min Xu <[email protected]> Cc: Jiewen Yao <[email protected]> Cc: Tom Lendacky <[email protected]> Cc: Jordan Justen <[email protected]> Cc: Ard Biesheuvel <[email protected]> Cc: Erdem Aktas <[email protected]> Cc: Gerd Hoffmann <[email protected]> Acked-by: Jiewen Yao <[email protected]> Acked-by: Gerd Hoffmann <[email protected]> Signed-off-by: Brijesh Singh <[email protected]> --- OvmfPkg/OvmfPkg.dec | 6 ++++++ OvmfPkg/OvmfPkgX64.fdf | 3 +++ OvmfPkg/ResetVector/ResetVector.inf | 2 ++ OvmfPkg/ResetVector/ResetVector.nasmb | 2 ++ OvmfPkg/ResetVector/X64/OvmfSevMetadata.asm | 9 +++++++++ 5 files changed, 22 insertions(+) diff --git a/OvmfPkg/OvmfPkg.dec b/OvmfPkg/OvmfPkg.dec index 1be8d5dccbc7..3e4e80a1e5a0 100644 --- a/OvmfPkg/OvmfPkg.dec +++ b/OvmfPkg/OvmfPkg.dec @@ -340,6 +340,12 @@ [PcdsFixedAtBuild] # header definition. gUefiOvmfPkgTokenSpaceGuid.PcdOvmfConfidentialComputingWorkAreaHeader|4|UINT32|0x51 + ## The base address and size of the SEV-SNP Secrets Area that contains + # the VM platform communication key used to send and recieve the + # messages to the PSP. If this is set in the .fdf, the platform + # is responsible to reserve this area from DXE phase overwrites. + gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSnpSecretsBase|0|UINT32|0x52 + gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSnpSecretsSize|0|UINT32|0x53 [PcdsDynamic, PcdsDynamicEx] gUefiOvmfPkgTokenSpaceGuid.PcdEmuVariableEvent|0|UINT64|2 diff --git a/OvmfPkg/OvmfPkgX64.fdf b/OvmfPkg/OvmfPkgX64.fdf index b6cc3cabdd69..1313c7f016bf 100644 --- a/OvmfPkg/OvmfPkgX64.fdf +++ b/OvmfPkg/OvmfPkgX64.fdf @@ -88,6 +88,9 @@ [FD.MEMFD] 0x00C000|0x001000 gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSecGhcbBackupBase|gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSecGhcbBackupSize +0x00D000|0x001000 +gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSnpSecretsBase|gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSnpSecretsSize + 0x010000|0x010000 gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSecPeiTempRamBase|gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSecPeiTempRamSize diff --git a/OvmfPkg/ResetVector/ResetVector.inf b/OvmfPkg/ResetVector/ResetVector.inf index a2520dde5508..09454d0797e6 100644 --- a/OvmfPkg/ResetVector/ResetVector.inf +++ b/OvmfPkg/ResetVector/ResetVector.inf @@ -50,3 +50,5 @@ [FixedPcd] gUefiOvmfPkgTokenSpaceGuid.PcdSevLaunchSecretSize gUefiOvmfPkgTokenSpaceGuid.PcdQemuHashTableBase gUefiOvmfPkgTokenSpaceGuid.PcdQemuHashTableSize + gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSnpSecretsBase + gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSnpSecretsSize diff --git a/OvmfPkg/ResetVector/ResetVector.nasmb b/OvmfPkg/ResetVector/ResetVector.nasmb index 6a3b1b73cf53..e6a868730897 100644 --- a/OvmfPkg/ResetVector/ResetVector.nasmb +++ b/OvmfPkg/ResetVector/ResetVector.nasmb @@ -78,6 +78,8 @@ %define SEV_ES_WORK_AREA_RDRAND (FixedPcdGet32 (PcdSevEsWorkAreaBase) + 8) %define SEV_ES_WORK_AREA_ENC_MASK (FixedPcdGet32 (PcdSevEsWorkAreaBase) + 16) %define SEV_ES_VC_TOP_OF_STACK (FixedPcdGet32 (PcdOvmfSecPeiTempRamBase) + FixedPcdGet32 (PcdOvmfSecPeiTempRamSize)) + %define SEV_SNP_SECRETS_BASE (FixedPcdGet32 (PcdOvmfSnpSecretsBase)) + %define SEV_SNP_SECRETS_SIZE (FixedPcdGet32 (PcdOvmfSnpSecretsSize)) %include "Ia32/Flat32ToFlat64.asm" %include "Ia32/AmdSev.asm" %include "Ia32/PageTables64.asm" diff --git a/OvmfPkg/ResetVector/X64/OvmfSevMetadata.asm b/OvmfPkg/ResetVector/X64/OvmfSevMetadata.asm index c42ad779be49..eba861129333 100644 --- a/OvmfPkg/ResetVector/X64/OvmfSevMetadata.asm +++ b/OvmfPkg/ResetVector/X64/OvmfSevMetadata.asm @@ -14,6 +14,9 @@ BITS 64 ; The section must be accepted or validated by the VMM before the boot %define OVMF_SECTION_TYPE_SNP_SEC_MEM 0x1 +; AMD SEV-SNP specific sections +%define OVMF_SECTION_TYPE_SNP_SECRETS 0x2 + ALIGN 16 TIMES (15 - ((OvmfSevGuidedStructureEnd - OvmfSevGuidedStructureStart + 15) % 16)) DB 0 @@ -30,5 +33,11 @@ _Descriptor: DD OVMF_SEV_METADATA_VERSION ; Version DD (OvmfSevGuidedStructureEnd - _Descriptor - 16) / 12 ; Number of sections +; SEV-SNP Secrets page +SevSnpSecrets: + DD SEV_SNP_SECRETS_BASE + DD SEV_SNP_SECRETS_SIZE + DD OVMF_SECTION_TYPE_SNP_SECRETS + OvmfSevGuidedStructureEnd: ALIGN 16 -- 2.25.1 -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#82568): https://edk2.groups.io/g/devel/message/82568 Mute This Topic: https://groups.io/mt/86530711/21656 Group Owner: [email protected] Unsubscribe: https://edk2.groups.io/g/devel/unsub [[email protected]] -=-=-=-=-=-=-=-=-=-=-=-
