OvmfPkg: Refactor MeasureHobList

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=4243

MeasureHobList once was implemented in PeilessStartupLib and it does
measurement and logging for TdHob in one go, using TpmMeasureAndLogData().
But it doesn't work in SEC.

This patch splits MeasureHobList into 2 functions and implement them in
SecTdxHelperLib.
 - TdxHelperMeasureTdHob
 - TdxHelperBuildGuidHobForTdxMeasurement

TdxHelperMeasureTdHob measures the TdHob and stores the hash value in
WorkArea. TdxHelperBuildGuidHobForTdxMeasurement builds GuidHob for the
measurement based on the hash value in WorkArea.

After these 2 functions are introduced, PeilessStartupLib should also be
updated:
 - Call these 2 functions instead of the MeasureHobList
 - Delete the duplicated codes in PeilessStartupLib

Cc: Erdem Aktas <erdemaktas@google.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Michael Roth <michael.roth@amd.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Signed-off-by: Min Xu <min.m.xu@intel.com>

4 files changed, 297 insertions, 1 deletions

diff --git a/OvmfPkg/IntelTdx/IntelTdxX64.dsc b/OvmfPkg/IntelTdx/IntelTdxX64.dsc
index 0f1e970fbb..920f1c6080 100644
--- a/OvmfPkg/IntelTdx/IntelTdxX64.dsc
+++ b/OvmfPkg/IntelTdx/IntelTdxX64.dsc
@@ -549,6 +549,7 @@
     <LibraryClasses>

       NULL|MdeModulePkg/Library/LzmaCustomDecompressLib/LzmaCustomDecompressLib.inf

       TpmMeasurementLib|SecurityPkg/Library/SecTpmMeasurementLib/SecTpmMeasurementLibTdx.inf

+      NULL|OvmfPkg/IntelTdx/TdxHelperLib/SecTdxHelperLib.inf

       BaseCryptLib|CryptoPkg/Library/BaseCryptLib/SecCryptLib.inf

       HashLib|SecurityPkg/Library/HashLibTdx/HashLibTdx.inf

       NULL|SecurityPkg/Library/HashInstanceLibSha384/HashInstanceLibSha384.inf

diff --git a/OvmfPkg/IntelTdx/TdxHelperLib/SecTdxHelper.c b/OvmfPkg/IntelTdx/TdxHelperLib/SecTdxHelper.c
index ef958b3359..6ca6f01aff 100644
--- a/OvmfPkg/IntelTdx/TdxHelperLib/SecTdxHelper.c
+++ b/OvmfPkg/IntelTdx/TdxHelperLib/SecTdxHelper.c
@@ -8,6 +8,31 @@
 **/

 

 #include <PiPei.h>

+#include <Library/BaseLib.h>

+#include <Library/DebugLib.h>

+#include <Library/HobLib.h>

+#include <Library/BaseCryptLib.h>

+#include <Library/BaseMemoryLib.h>

+#include <IndustryStandard/Tdx.h>

+#include <IndustryStandard/IntelTdx.h>

+#include <IndustryStandard/Tpm20.h>

+#include <Library/TdxLib.h>

+#include <Pi/PrePiHob.h>

+#include <WorkArea.h>

+#include <ConfidentialComputingGuestAttr.h>

+#include <Library/TdxHelperLib.h>

+

+/**

+  Build the GuidHob for tdx measurements which were done in SEC phase.

+  The measurement values are stored in WorkArea.

+

+  @retval EFI_SUCCESS  The GuidHob is built successfully

+  @retval Others       Other errors as indicated

+**/

+EFI_STATUS

+InternalBuildGuidHobForTdxMeasurement (

+  VOID

+  );

 

 /**

   In Tdx guest, some information need to be passed from host VMM to guest

@@ -28,6 +53,58 @@ TdxHelperProcessTdHob (
 }

 

 /**

+ * Calculate the sha384 of input Data and extend it to RTMR register.

+ *

+ * @param RtmrIndex       Index of the RTMR register

+ * @param DataToHash      Data to be hashed

+ * @param DataToHashLen   Length of the data

+ * @param Digest          Hash value of the input data

+ * @param DigestLen       Length of the hash value

+ *

+ * @retval EFI_SUCCESS    Successfully hash and extend to RTMR

+ * @retval Others         Other errors as indicated

+ */

+STATIC

+EFI_STATUS

+HashAndExtendToRtmr (

+  IN UINT32  RtmrIndex,

+  IN VOID    *DataToHash,

+  IN UINTN   DataToHashLen,

+  OUT UINT8  *Digest,

+  IN  UINTN  DigestLen

+  )

+{

+  EFI_STATUS  Status;

+

+  if ((DataToHash == NULL) || (DataToHashLen == 0)) {

+    return EFI_INVALID_PARAMETER;

+  }

+

+  if ((Digest == NULL) || (DigestLen != SHA384_DIGEST_SIZE)) {

+    return EFI_INVALID_PARAMETER;

+  }

+

+  //

+  // Calculate the sha384 of the data

+  //

+  if (!Sha384HashAll (DataToHash, DataToHashLen, Digest)) {

+    return EFI_ABORTED;

+  }

+

+  //

+  // Extend to RTMR

+  //

+  Status = TdExtendRtmr (

+             (UINT32 *)Digest,

+             SHA384_DIGEST_SIZE,

+             (UINT8)RtmrIndex

+             );

+

+  ASSERT (!EFI_ERROR (Status));

+  return Status;

+}

+

+/**

   In Tdx guest, TdHob is passed from host VMM to guest firmware and it contains

   the information of the memory resource. From the security perspective before

   it is consumed, it should be measured and extended.

@@ -41,7 +118,47 @@ TdxHelperMeasureTdHob (
   VOID

   )

 {

-  return EFI_UNSUPPORTED;

+  EFI_PEI_HOB_POINTERS  Hob;

+  EFI_STATUS            Status;

+  UINT8                 Digest[SHA384_DIGEST_SIZE];

+  OVMF_WORK_AREA        *WorkArea;

+  VOID                  *TdHob;

+

+  TdHob   = (VOID *)(UINTN)FixedPcdGet32 (PcdOvmfSecGhcbBase);

+  Hob.Raw = (UINT8 *)TdHob;

+

+  //

+  // Walk thru the TdHob list until end of list.

+  //

+  while (!END_OF_HOB_LIST (Hob)) {

+    Hob.Raw = GET_NEXT_HOB (Hob);

+  }

+

+  Status = HashAndExtendToRtmr (

+             0,

+             (UINT8 *)TdHob,

+             (UINTN)((UINT8 *)Hob.Raw - (UINT8 *)TdHob),

+             Digest,

+             SHA384_DIGEST_SIZE

+             );

+

+  if (EFI_ERROR (Status)) {

+    return Status;

+  }

+

+  //

+  // This function is called in SEC phase and at that moment the Hob service

+  // is not available. So the TdHob measurement value is stored in workarea.

+  //

+  WorkArea = (OVMF_WORK_AREA *)FixedPcdGet32 (PcdOvmfWorkAreaBase);

+  if (WorkArea == NULL) {

+    return EFI_DEVICE_ERROR;

+  }

+

+  WorkArea->TdxWorkArea.SecTdxWorkArea.TdxMeasurementsData.MeasurementsBitmap |= TDX_MEASUREMENT_TDHOB_BITMASK;

+  CopyMem (WorkArea->TdxWorkArea.SecTdxWorkArea.TdxMeasurementsData.TdHobHashValue, Digest, SHA384_DIGEST_SIZE);

+

+  return EFI_SUCCESS;

 }

 

 /**

@@ -74,5 +191,9 @@ TdxHelperBuildGuidHobForTdxMeasurement (
   VOID

   )

 {

+ #ifdef TDX_PEI_LESS_BOOT

+  return InternalBuildGuidHobForTdxMeasurement ();

+ #else

   return EFI_UNSUPPORTED;

+ #endif

 }

diff --git a/OvmfPkg/IntelTdx/TdxHelperLib/SecTdxHelperLib.inf b/OvmfPkg/IntelTdx/TdxHelperLib/SecTdxHelperLib.inf
index 3c6b96f775..d17b84c01f 100644
--- a/OvmfPkg/IntelTdx/TdxHelperLib/SecTdxHelperLib.inf
+++ b/OvmfPkg/IntelTdx/TdxHelperLib/SecTdxHelperLib.inf
@@ -24,6 +24,7 @@
 

 [Sources]

   SecTdxHelper.c

+  TdxMeasurementHob.c

 

 [Packages]

   CryptoPkg/CryptoPkg.dec

diff --git a/OvmfPkg/IntelTdx/TdxHelperLib/TdxMeasurementHob.c b/OvmfPkg/IntelTdx/TdxHelperLib/TdxMeasurementHob.c
new file mode 100644
index 0000000000..6cbc7600ad
--- /dev/null
+++ b/OvmfPkg/IntelTdx/TdxHelperLib/TdxMeasurementHob.c
@@ -0,0 +1,173 @@
+/** @file

+  Build GuidHob for tdx measurement.

+

+  Copyright (c) 2022 - 2023, 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 <IndustryStandard/Tpm20.h>

+#include <IndustryStandard/UefiTcgPlatform.h>

+#include <Library/HobLib.h>

+#include <Library/PrintLib.h>

+#include <WorkArea.h>

+

+#pragma pack(1)

+

+#define HANDOFF_TABLE_DESC  "TdxTable"

+typedef struct {

+  UINT8                      TableDescriptionSize;

+  UINT8                      TableDescription[sizeof (HANDOFF_TABLE_DESC)];

+  UINT64                     NumberOfTables;

+  EFI_CONFIGURATION_TABLE    TableEntry[1];

+} TDX_HANDOFF_TABLE_POINTERS2;

+

+#pragma pack()

+

+/**

+ * Build GuidHob for Tdx measurement.

+ *

+ * Tdx measurement includes the measurement of TdHob and CFV. They're measured

+ * and extended to RTMR registers in SEC phase. Because at that moment the Hob

+ * service are not available. So the values of the measurement are saved in

+ * workarea and will be built into GuidHob after the Hob service is ready.

+ *

+ * @param RtmrIndex     RTMR index

+ * @param EventType     Event type

+ * @param EventData     Event data

+ * @param EventSize     Size of event data

+ * @param HashValue     Hash value

+ * @param HashSize      Size of hash

+ *

+ * @retval EFI_SUCCESS  Successfully build the GuidHobs

+ * @retval Others       Other error as indicated

+ */

+STATIC

+EFI_STATUS

+BuildTdxMeasurementGuidHob (

+  UINT32  RtmrIndex,

+  UINT32  EventType,

+  UINT8   *EventData,

+  UINT32  EventSize,

+  UINT8   *HashValue,

+  UINT32  HashSize

+  )

+{

+  VOID                *EventHobData;

+  UINT8               *Ptr;

+  TPML_DIGEST_VALUES  *TdxDigest;

+

+  if (HashSize != SHA384_DIGEST_SIZE) {

+    return EFI_INVALID_PARAMETER;

+  }

+

+  #define TDX_DIGEST_VALUE_LEN  (sizeof (UINT32) + sizeof (TPMI_ALG_HASH) + SHA384_DIGEST_SIZE)

+

+  EventHobData = BuildGuidHob (

+                   &gCcEventEntryHobGuid,

+                   sizeof (TCG_PCRINDEX) + sizeof (TCG_EVENTTYPE) +

+                   TDX_DIGEST_VALUE_LEN +

+                   sizeof (UINT32) + EventSize

+                   );

+

+  if (EventHobData == NULL) {

+    return EFI_OUT_OF_RESOURCES;

+  }

+

+  Ptr = (UINT8 *)EventHobData;

+

+  //

+  // There are 2 types of measurement registers in TDX: MRTD and RTMR[0-3].

+  // According to UEFI Spec 2.10 Section 38.4.1, RTMR[0-3] is mapped to MrIndex[1-4].

+  // So RtmrIndex must be increased by 1 before the event log is created.

+  //

+  RtmrIndex++;

+  CopyMem (Ptr, &RtmrIndex, sizeof (UINT32));

+  Ptr += sizeof (UINT32);

+

+  CopyMem (Ptr, &EventType, sizeof (TCG_EVENTTYPE));

+  Ptr += sizeof (TCG_EVENTTYPE);

+

+  TdxDigest                     = (TPML_DIGEST_VALUES *)Ptr;

+  TdxDigest->count              = 1;

+  TdxDigest->digests[0].hashAlg = TPM_ALG_SHA384;

+  CopyMem (

+    TdxDigest->digests[0].digest.sha384,

+    HashValue,

+    SHA384_DIGEST_SIZE

+    );

+  Ptr += TDX_DIGEST_VALUE_LEN;

+

+  CopyMem (Ptr, &EventSize, sizeof (UINT32));

+  Ptr += sizeof (UINT32);

+

+  CopyMem (Ptr, (VOID *)EventData, EventSize);

+  Ptr += EventSize;

+

+  return EFI_SUCCESS;

+}

+

+/**

+  Build the GuidHob for tdx measurements which were done in SEC phase.

+  The measurement values are stored in WorkArea.

+

+  @retval EFI_SUCCESS  The GuidHob is built successfully

+  @retval Others       Other errors as indicated

+**/

+EFI_STATUS

+InternalBuildGuidHobForTdxMeasurement (

+  VOID

+  )

+{

+  EFI_STATUS                   Status;

+  OVMF_WORK_AREA               *WorkArea;

+  VOID                         *TdHobList;

+  TDX_HANDOFF_TABLE_POINTERS2  HandoffTables;

+  UINT8                        *HashValue;

+

+  if (!TdIsEnabled ()) {

+    ASSERT (FALSE);

+    return EFI_UNSUPPORTED;

+  }

+

+  WorkArea = (OVMF_WORK_AREA *)FixedPcdGet32 (PcdOvmfWorkAreaBase);

+  if (WorkArea == NULL) {

+    return EFI_ABORTED;

+  }

+

+  Status = EFI_SUCCESS;

+

+  //

+  // Build the GuidHob for TdHob measurement

+  //

+  TdHobList = (VOID *)(UINTN)FixedPcdGet32 (PcdOvmfSecGhcbBase);

+  if (WorkArea->TdxWorkArea.SecTdxWorkArea.TdxMeasurementsData.MeasurementsBitmap & TDX_MEASUREMENT_TDHOB_BITMASK) {

+    HashValue                          = WorkArea->TdxWorkArea.SecTdxWorkArea.TdxMeasurementsData.TdHobHashValue;

+    HandoffTables.TableDescriptionSize = sizeof (HandoffTables.TableDescription);

+    CopyMem (HandoffTables.TableDescription, HANDOFF_TABLE_DESC, sizeof (HandoffTables.TableDescription));

+    HandoffTables.NumberOfTables = 1;

+    CopyGuid (&(HandoffTables.TableEntry[0].VendorGuid), &gUefiOvmfPkgTokenSpaceGuid);

+    HandoffTables.TableEntry[0].VendorTable = TdHobList;

+

+    Status = BuildTdxMeasurementGuidHob (

+               0,                               // RtmrIndex

+               EV_EFI_HANDOFF_TABLES2,          // EventType

+               (UINT8 *)(UINTN)&HandoffTables,  // EventData

+               sizeof (HandoffTables),          // EventSize

+               HashValue,                       // HashValue

+               SHA384_DIGEST_SIZE               // HashSize

+               );

+  }

+

+  if (EFI_ERROR (Status)) {

+    ASSERT (FALSE);

+    return Status;

+  }

+

+  return EFI_SUCCESS;

+}