RFC: https://bugzilla.tianocore.org/show_bug.cgi?id=3853
TdHobList and Configuration FV are external data provided by Host VMM.
These are not trusted in Td guest. So they should be validated , measured
and extended to Td RTMR registers. In the meantime 2 EFI_CC_EVENT_HOB are
created. These 2 GUIDed HOBs carry the hash value of TdHobList and
Configuration FV. In DXE phase EFI_CC_EVENT can be created based on these
2 GUIDed HOBs.
Cc: Ard Biesheuvel <ardb+tianoc...@kernel.org>
Cc: Jiewen Yao <jiewen....@intel.com>
Cc: Jordan Justen <jordan.l.jus...@intel.com>
Cc: Brijesh Singh <brijesh.si...@amd.com>
Cc: Erdem Aktas <erdemak...@google.com>
Cc: James Bottomley <j...@linux.ibm.com>
Cc: Jiewen Yao <jiewen....@intel.com>
Cc: Tom Lendacky <thomas.lenda...@amd.com>
Cc: Gerd Hoffmann <kra...@redhat.com>
Signed-off-by: Min Xu <min.m...@intel.com>
---
OvmfPkg/IntelTdx/IntelTdxX64.dsc | 4 +
OvmfPkg/Library/PeilessStartupLib/IntelTdx.c | 163 ++++++++++++++++++
.../PeilessStartupLib/PeilessStartup.c | 31 ++++
.../PeilessStartupInternal.h | 17 ++
.../PeilessStartupLib/PeilessStartupLib.inf | 8 +-
5 files changed, 221 insertions(+), 2 deletions(-)
create mode 100644 OvmfPkg/Library/PeilessStartupLib/IntelTdx.c
diff --git a/OvmfPkg/IntelTdx/IntelTdxX64.dsc b/OvmfPkg/IntelTdx/IntelTdxX64.dsc
index 245155d41b30..e6cd10a120a8 100644
--- a/OvmfPkg/IntelTdx/IntelTdxX64.dsc
+++ b/OvmfPkg/IntelTdx/IntelTdxX64.dsc
@@ -520,6 +520,10 @@
OvmfPkg/IntelTdx/Sec/SecMain.inf {
<LibraryClasses>
NULL|MdeModulePkg/Library/LzmaCustomDecompressLib/LzmaCustomDecompressLib.inf
+
SecMeasurementLib|OvmfPkg/Library/SecMeasurementLib/SecMeasurementLibTdx.inf
+ BaseCryptLib|CryptoPkg/Library/BaseCryptLib/SecCryptLib.inf
+ HashLib|SecurityPkg/Library/HashLibTdx/HashLibTdx.inf
+ NULL|SecurityPkg/Library/HashInstanceLibSha384/HashInstanceLibSha384.inf
}
#
diff --git a/OvmfPkg/Library/PeilessStartupLib/IntelTdx.c
b/OvmfPkg/Library/PeilessStartupLib/IntelTdx.c
new file mode 100644
index 000000000000..d240d3b7719f
--- /dev/null
+++ b/OvmfPkg/Library/PeilessStartupLib/IntelTdx.c
@@ -0,0 +1,163 @@
+/** @file
+ Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#include <PiPei.h>
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/DebugLib.h>
+#include <Guid/VariableFormat.h>
+#include <Guid/SystemNvDataGuid.h>
+#include "PeilessStartupInternal.h"
+
+/**
+ Check padding data all bit should be 1.
+
+ @param[in] Buffer - A pointer to buffer header
+ @param[in] BufferSize - Buffer size
+
+ @retval TRUE - The padding data is valid.
+ @retval TRUE - The padding data is invalid.
+
+**/
+BOOLEAN
+CheckPaddingData (
+ IN UINT8 *Buffer,
+ IN UINT32 BufferSize
+ )
+{
+ UINT32 index;
+
+ for (index = 0; index < BufferSize; index++) {
+ if (Buffer[index] != 0xFF) {
+ return FALSE;
+ }
+ }
+
+ return TRUE;
+}
+
+/**
+ Check the integrity of CFV data.
+
+ @param[in] TdxCfvBase - A pointer to CFV header
+ @param[in] TdxCfvSize - CFV data size
+
+ @retval TRUE - The CFV data is valid.
+ @retval FALSE - The CFV data is invalid.
+
+**/
+BOOLEAN
+EFIAPI
+TdxValidateCfv (
+ IN UINT8 *TdxCfvBase,
+ IN UINT32 TdxCfvSize
+ )
+{
+ UINT16 Checksum;
+ UINTN VariableBase;
+ UINT32 VariableOffset;
+ UINT32 VariableOffsetBeforeAlign;
+ EFI_FIRMWARE_VOLUME_HEADER *CfvFvHeader;
+ VARIABLE_STORE_HEADER *CfvVariableStoreHeader;
+ AUTHENTICATED_VARIABLE_HEADER *VariableHeader;
+
+ static EFI_GUID FvHdrGUID = EFI_SYSTEM_NV_DATA_FV_GUID;
+ static EFI_GUID VarStoreHdrGUID = EFI_AUTHENTICATED_VARIABLE_GUID;
+
+ VariableOffset = 0;
+
+ if (TdxCfvBase == NULL) {
+ DEBUG ((DEBUG_ERROR, "TDX CFV: CFV pointer is NULL\n"));
+ return FALSE;
+ }
+
+ //
+ // Verify the header zerovetor, filesystemguid,
+ // revision, signature, attributes, fvlength, checksum
+ // HeaderLength cannot be an odd number
+ //
+ CfvFvHeader = (EFI_FIRMWARE_VOLUME_HEADER *)TdxCfvBase;
+
+ if ((!IsZeroBuffer (CfvFvHeader->ZeroVector, 16)) ||
+ (!CompareGuid (&FvHdrGUID, &CfvFvHeader->FileSystemGuid)) ||
+ (CfvFvHeader->Signature != EFI_FVH_SIGNATURE) ||
+ (CfvFvHeader->Attributes != 0x4feff) ||
+ (CfvFvHeader->Revision != EFI_FVH_REVISION) ||
+ (CfvFvHeader->FvLength != TdxCfvSize)
+ )
+ {
+ DEBUG ((DEBUG_ERROR, "TDX CFV: Basic FV headers were invalid\n"));
+ return FALSE;
+ }
+
+ //
+ // Verify the header checksum
+ //
+ Checksum = CalculateSum16 ((VOID *)CfvFvHeader, CfvFvHeader->HeaderLength);
+
+ if (Checksum != 0) {
+ DEBUG ((DEBUG_ERROR, "TDX CFV: FV checksum was invalid\n"));
+ return FALSE;
+ }
+
+ //
+ // Verify the header signature, size, format, state
+ //
+ CfvVariableStoreHeader = (VARIABLE_STORE_HEADER *)(TdxCfvBase +
CfvFvHeader->HeaderLength);
+ if ((!CompareGuid (&VarStoreHdrGUID, &CfvVariableStoreHeader->Signature)) ||
+ (CfvVariableStoreHeader->Format != VARIABLE_STORE_FORMATTED) ||
+ (CfvVariableStoreHeader->State != VARIABLE_STORE_HEALTHY) ||
+ (CfvVariableStoreHeader->Size > (CfvFvHeader->FvLength -
CfvFvHeader->HeaderLength)) ||
+ (CfvVariableStoreHeader->Size < sizeof (VARIABLE_STORE_HEADER))
+ )
+ {
+ DEBUG ((DEBUG_ERROR, "TDX CFV: Variable Store header was invalid\n"));
+ return FALSE;
+ }
+
+ //
+ // Verify the header startId, state
+ // Verify data to the end
+ //
+ VariableBase = (UINTN)TdxCfvBase + CfvFvHeader->HeaderLength + sizeof
(VARIABLE_STORE_HEADER);
+ while (VariableOffset < (CfvVariableStoreHeader->Size - sizeof
(VARIABLE_STORE_HEADER))) {
+ VariableHeader = (AUTHENTICATED_VARIABLE_HEADER *)(VariableBase +
VariableOffset);
+ if (VariableHeader->StartId != VARIABLE_DATA) {
+ if (!CheckPaddingData ((UINT8 *)VariableHeader,
CfvVariableStoreHeader->Size - sizeof (VARIABLE_STORE_HEADER) -
VariableOffset)) {
+ DEBUG ((DEBUG_ERROR, "TDX CFV: Variable header was invalid\n"));
+ return FALSE;
+ }
+
+ VariableOffset = CfvVariableStoreHeader->Size - sizeof
(VARIABLE_STORE_HEADER);
+ } else {
+ if (!((VariableHeader->State == VAR_IN_DELETED_TRANSITION) ||
+ (VariableHeader->State == VAR_DELETED) ||
+ (VariableHeader->State == VAR_HEADER_VALID_ONLY) ||
+ (VariableHeader->State == VAR_ADDED)))
+ {
+ DEBUG ((DEBUG_ERROR, "TDX CFV: Variable header was invalid\n"));
+ return FALSE;
+ }
+
+ VariableOffset += sizeof (AUTHENTICATED_VARIABLE_HEADER) +
VariableHeader->NameSize + VariableHeader->DataSize;
+ // Verify VariableOffset should be less than or equal
CfvVariableStoreHeader->Size - sizeof(VARIABLE_STORE_HEADER)
+ if (VariableOffset > (CfvVariableStoreHeader->Size - sizeof
(VARIABLE_STORE_HEADER))) {
+ DEBUG ((DEBUG_ERROR, "TDX CFV: Variable header was invalid\n"));
+ return FALSE;
+ }
+
+ VariableOffsetBeforeAlign = VariableOffset;
+ // 4 byte align
+ VariableOffset = (VariableOffset + 3) & (UINTN)(~3);
+
+ if (!CheckPaddingData ((UINT8 *)(VariableBase +
VariableOffsetBeforeAlign), VariableOffset - VariableOffsetBeforeAlign)) {
+ DEBUG ((DEBUG_ERROR, "TDX CFV: Variable header was invalid\n"));
+ return FALSE;
+ }
+ }
+ }
+
+ return TRUE;
+}
diff --git a/OvmfPkg/Library/PeilessStartupLib/PeilessStartup.c
b/OvmfPkg/Library/PeilessStartupLib/PeilessStartup.c
index 126eb74048f4..54236b956c52 100644
--- a/OvmfPkg/Library/PeilessStartupLib/PeilessStartup.c
+++ b/OvmfPkg/Library/PeilessStartupLib/PeilessStartup.c
@@ -20,6 +20,7 @@
#include <ConfidentialComputingGuestAttr.h>
#include <Guid/MemoryTypeInformation.h>
#include <OvmfPlatforms.h>
+#include <Library/SecMeasurementLib.h>
#include "PeilessStartupInternal.h"
#define GET_GPAW_INIT_STATE(INFO) ((UINT8) ((INFO) & 0x3f))
@@ -133,11 +134,13 @@ PeilessStartup (
UINT32 DxeCodeSize;
TD_RETURN_DATA TdReturnData;
VOID *VmmHobList;
+ UINT8 *CfvBase;
Status = EFI_SUCCESS;
BootFv = NULL;
VmmHobList = NULL;
SecCoreData = (EFI_SEC_PEI_HAND_OFF *)Context;
+ CfvBase = (UINT8 *)(UINTN)FixedPcdGet32 (PcdCfvBase);
ZeroMem (&PlatformInfoHob, sizeof (PlatformInfoHob));
@@ -167,6 +170,34 @@ PeilessStartup (
DEBUG ((DEBUG_INFO, "HobList: %p\n", GetHobList ()));
+ if (TdIsEnabled ()) {
+ //
+ // Measure HobList
+ //
+ Status = MeasureHobList (VmmHobList);
+ if (EFI_ERROR (Status)) {
+ ASSERT (FALSE);
+ CpuDeadLoop ();
+ }
+
+ //
+ // Validate Tdx CFV
+ //
+ if (!TdxValidateCfv (CfvBase, FixedPcdGet32 (PcdCfvRawDataSize))) {
+ ASSERT (FALSE);
+ CpuDeadLoop ();
+ }
+
+ //
+ // Measure Tdx CFV
+ //
+ Status = MeasureFvImage ((EFI_PHYSICAL_ADDRESS)(UINTN)CfvBase,
FixedPcdGet32 (PcdCfvRawDataSize), 1);
+ if (EFI_ERROR (Status)) {
+ ASSERT (FALSE);
+ CpuDeadLoop ();
+ }
+ }
+
//
// Initialize the Platform
//
diff --git a/OvmfPkg/Library/PeilessStartupLib/PeilessStartupInternal.h
b/OvmfPkg/Library/PeilessStartupLib/PeilessStartupInternal.h
index 23e9e0be53f1..dd79b8a06b44 100644
--- a/OvmfPkg/Library/PeilessStartupLib/PeilessStartupInternal.h
+++ b/OvmfPkg/Library/PeilessStartupLib/PeilessStartupInternal.h
@@ -52,4 +52,21 @@ EFIAPI
ConstructSecHobList (
);
+/**
+ Check the integrity of CFV data.
+
+ @param[in] TdxCfvBase - A pointer to CFV header
+ @param[in] TdxCfvSize - CFV data size
+
+ @retval TRUE - The CFV data is valid.
+ @retval FALSE - The CFV data is invalid.
+
+**/
+BOOLEAN
+EFIAPI
+TdxValidateCfv (
+ IN UINT8 *TdxCfvBase,
+ IN UINT32 TdxCfvSize
+ );
+
#endif
diff --git a/OvmfPkg/Library/PeilessStartupLib/PeilessStartupLib.inf
b/OvmfPkg/Library/PeilessStartupLib/PeilessStartupLib.inf
index 8791984586a4..c5d291f02bcd 100644
--- a/OvmfPkg/Library/PeilessStartupLib/PeilessStartupLib.inf
+++ b/OvmfPkg/Library/PeilessStartupLib/PeilessStartupLib.inf
@@ -29,8 +29,7 @@
PeilessStartup.c
Hob.c
DxeLoad.c
-
-[Sources.X64]
+ IntelTdx.c
X64/VirtualMemory.c
[Packages]
@@ -39,6 +38,8 @@
UefiCpuPkg/UefiCpuPkg.dec
OvmfPkg/OvmfPkg.dec
EmbeddedPkg/EmbeddedPkg.dec
+ CryptoPkg/CryptoPkg.dec
+ SecurityPkg/SecurityPkg.dec
[LibraryClasses]
BaseLib
@@ -56,6 +57,8 @@
PrePiLib
QemuFwCfgLib
PlatformInitLib
+ HashLib
+ SecMeasurementLib
[Guids]
gEfiHobMemoryAllocModuleGuid
@@ -63,6 +66,7 @@
gUefiOvmfPkgPlatformInfoGuid
gEfiMemoryTypeInformationGuid
gPcdDataBaseHobGuid
+ gCcEventEntryHobGuid
[Pcd]
gUefiOvmfPkgTokenSpaceGuid.PcdCfvBase
--
2.29.2.windows.2
-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#88988): https://edk2.groups.io/g/devel/message/88988
Mute This Topic: https://groups.io/mt/90531017/21656
Group Owner: devel+ow...@edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com]
-=-=-=-=-=-=-=-=-=-=-=-
