Re: [PATCH v4 1/1] UefiCpuPkg: Extend measurement of microcode patches to TPM

["Ni, Ray" <ray.ni@intel.com>]

Reviewed-by: Ray Ni <ray.ni@intel.com>

-----Original Message-----
From: Yang, Longlong <longlong.yang@intel.com> 
Sent: Tuesday, December 14, 2021 3:19 PM
To: devel@edk2.groups.io
Cc: Yang, Longlong <longlong.yang@intel.com>; Dong, Eric <eric.dong@intel.com>; Ni, Ray <ray.ni@intel.com>; Kumar, Rahul1 <rahul1.kumar@intel.com>; Yao, Jiewen <jiewen.yao@intel.com>; Xu, Min M <min.m.xu@intel.com>; Zhang, Qi1 <qi1.zhang@intel.com>
Subject: [PATCH v4 1/1] UefiCpuPkg: Extend measurement of microcode patches to TPM

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3683

TCG specification says BIOS should extend measurement of microcode to TPM.
However, reference BIOS is not doing this. BIOS shall extend measurement of
microcode to TPM.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Min M Xu <min.m.xu@intel.com>
Cc: Qi Zhang <qi1.zhang@intel.com>
Signed-off-by: Longlong Yang <longlong.yang@intel.com>
---
 .../MicrocodeMeasurementDxe.c                 | 281 ++++++++++++++++++
 .../MicrocodeMeasurementDxe.inf               |  56 ++++
 .../MicrocodeMeasurementDxe.uni               |  15 +
 .../MicrocodeMeasurementDxeExtra.uni          |  12 +
 UefiCpuPkg/UefiCpuPkg.dsc                     |   1 +
 5 files changed, 365 insertions(+)
 create mode 100644 UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxe.c
 create mode 100644 UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxe.inf
 create mode 100644 UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxe.uni
 create mode 100644 UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxeExtra.uni

diff --git a/UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxe.c b/UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxe.c
new file mode 100644
index 000000000000..762ca159ff0e
--- /dev/null
+++ b/UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxe.c
@@ -0,0 +1,281 @@
+/** @file
+  This driver measures microcode patches to TPM.
+
+  This driver consumes gEdkiiMicrocodePatchHobGuid, packs all unique microcode patch found in gEdkiiMicrocodePatchHobGuid to a binary blob, and measures the binary blob to TPM.
+
+  Copyright (c) 2021, Intel Corporation. All rights reserved.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <IndustryStandard/UefiTcgPlatform.h>
+#include <Guid/EventGroup.h>
+#include <Guid/MicrocodePatchHob.h>
+#include <Library/DebugLib.h>
+#include <Library/UefiDriverEntryPoint.h>
+#include <Library/UefiLib.h>
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/HobLib.h>
+#include <Library/MicrocodeLib.h>
+#include <Library/TpmMeasurementLib.h>
+
+#define CPU_MICROCODE_MEASUREMENT_DESCRIPTION                "Microcode Measurement"
+#define CPU_MICROCODE_MEASUREMENT_EVENT_LOG_DESCRIPTION_LEN  sizeof (CPU_MICROCODE_MEASUREMENT_DESCRIPTION)
+
+#pragma pack(1)
+typedef struct {
+  UINT8    Description[CPU_MICROCODE_MEASUREMENT_EVENT_LOG_DESCRIPTION_LEN];
+  UINTN    NumberOfMicrocodePatchesMeasured;
+  UINTN    SizeOfMicrocodePatchesMeasured;
+} CPU_MICROCODE_MEASUREMENT_EVENT_LOG;
+#pragma pack()
+
+/**
+  Helping function.
+
+  The function is called by QuickSort to compare the order of offsets of
+  two microcode patches in RAM relative to their base address. Elements
+  will be in ascending order.
+
+  @param[in] Offset1   The pointer to the offset of first microcode patch.
+  @param[in] Offset2   The pointer to the offset of second microcode patch.
+
+  @retval 1                   The offset of first microcode patch is bigger than that of the second.
+  @retval -1                  The offset of first microcode patch is smaller than that of the second.
+  @retval 0                   The offset of first microcode patch equals to that of the second.
+**/
+INTN
+EFIAPI
+MicrocodePatchOffsetCompareFunction (
+  IN CONST VOID  *Offset1,
+  IN CONST VOID  *Offset2
+  )
+{
+  if (*(UINT64 *)(Offset1) > *(UINT64 *)(Offset2)) {
+    return 1;
+  } else if (*(UINT64 *)(Offset1) < *(UINT64 *)(Offset2)) {
+    return -1;
+  } else {
+    return 0;
+  }
+}
+
+/**
+  This function remove duplicate and invalid offsets in Offsets.
+
+  This function remove duplicate and invalid offsets in Offsets. Invalid offset means MAX_UINT64 in Offsets.
+
+  @param[in] Offsets        Microcode offset list.
+  @param[in, out] Count          On call as the count of raw microcode offset list; On return as count of the clean microcode offset list.
+  **/
+VOID
+RemoveDuplicateAndInvalidOffset (
+  IN     UINT64  *Offsets,
+  IN OUT UINTN   *Count
+  )
+{
+  UINTN   Index;
+  UINTN   NewCount;
+  UINT64  LastOffset;
+  UINT64  QuickSortBuffer;
+
+  //
+  // The order matters when packing all applied microcode patches to a single binary blob.
+  // Therefore it is a must to do sorting before packing.
+  // NOTE: Since microcode patches are sorted by their addresses in memory, the order of
+  // addresses in memory of all the microcode patches before sorting is required to be the
+  // same in every boot flow. If any future updates made this assumption untenable, then
+  // there needs a new solution to measure microcode patches.
+  //
+  QuickSort (
+    Offsets,
+    *Count,
+    sizeof (UINT64),
+    MicrocodePatchOffsetCompareFunction,
+    (VOID *)&QuickSortBuffer
+    );
+
+  NewCount   = 0;
+  LastOffset = MAX_UINT64;
+  for (Index = 0; Index < *Count; Index++) {
+    //
+    // When MAX_UINT64 element is met, all following elements are MAX_UINT64.
+    //
+    if (Offsets[Index] == MAX_UINT64) {
+      break;
+    }
+
+    //
+    // Remove duplicated offsets
+    //
+    if (Offsets[Index] != LastOffset) {
+      LastOffset        = Offsets[Index];
+      Offsets[NewCount] = Offsets[Index];
+      NewCount++;
+    }
+  }
+
+  *Count = NewCount;
+}
+
+/**
+  Callback function.
+
+  Called after signaling of the Ready to Boot Event. Measure microcode patches binary blob with event type EV_CPU_MICROCODE to PCR[1] in TPM.
+
+  @param[in] Event      Event whose notification function is being invoked.
+  @param[in] Context    Pointer to the notification function's context.
+
+**/
+VOID
+EFIAPI
+MeasureMicrocodePatches (
+  IN      EFI_EVENT  Event,
+  IN      VOID       *Context
+  )
+{
+  EFI_STATUS                           Status;
+  UINT32                               PCRIndex;
+  UINT32                               EventType;
+  CPU_MICROCODE_MEASUREMENT_EVENT_LOG  EventLog;
+  UINT32                               EventLogSize;
+  EFI_HOB_GUID_TYPE                    *GuidHob;
+  EDKII_MICROCODE_PATCH_HOB            *MicrocodePatchHob;
+  UINT64                               *Offsets;
+  UINTN                                Count;
+  UINTN                                Index;
+  UINTN                                TotalMicrocodeSize;
+  UINT8                                *MicrocodePatchesBlob;
+
+  PCRIndex  = 1;
+  EventType = EV_CPU_MICROCODE;
+  AsciiStrCpyS (
+    (CHAR8 *)(EventLog.Description),
+    CPU_MICROCODE_MEASUREMENT_EVENT_LOG_DESCRIPTION_LEN,
+    CPU_MICROCODE_MEASUREMENT_DESCRIPTION
+    );
+  EventLog.NumberOfMicrocodePatchesMeasured = 0;
+  EventLog.SizeOfMicrocodePatchesMeasured   = 0;
+  EventLogSize                              = sizeof (CPU_MICROCODE_MEASUREMENT_EVENT_LOG);
+  Offsets                                   = NULL;
+  TotalMicrocodeSize                        = 0;
+  Count                                     = 0;
+
+  GuidHob = GetFirstGuidHob (&gEdkiiMicrocodePatchHobGuid);
+  if (NULL == GuidHob) {
+    DEBUG ((DEBUG_ERROR, "ERROR: GetFirstGuidHob (&gEdkiiMicrocodePatchHobGuid) failed.\n"));
+    return;
+  }
+
+  MicrocodePatchHob = GET_GUID_HOB_DATA (GuidHob);
+  DEBUG (
+    (DEBUG_INFO,
+     "INFO: Got MicrocodePatchHob with microcode patches starting address:0x%x, microcode patches region size:0x%x, processor count:0x%x\n",
+     MicrocodePatchHob->MicrocodePatchAddress, MicrocodePatchHob->MicrocodePatchRegionSize,
+     MicrocodePatchHob->ProcessorCount)
+    );
+
+  Offsets = AllocateCopyPool (
+              MicrocodePatchHob->ProcessorCount * sizeof (UINT64),
+              MicrocodePatchHob->ProcessorSpecificPatchOffset
+              );
+  Count = MicrocodePatchHob->ProcessorCount;
+
+  RemoveDuplicateAndInvalidOffset (Offsets, &Count);
+
+  if (0 == Count) {
+    DEBUG ((DEBUG_INFO, "INFO: No microcode patch is ever applied, skip the measurement of microcode!\n"));
+    FreePool (Offsets);
+    return;
+  }
+
+  for (Index = 0; Index < Count; Index++) {
+    TotalMicrocodeSize +=
+      GetMicrocodeLength ((CPU_MICROCODE_HEADER *)((UINTN)(MicrocodePatchHob->MicrocodePatchAddress + Offsets[Index])));
+  }
+
+  EventLog.NumberOfMicrocodePatchesMeasured = Count;
+  EventLog.SizeOfMicrocodePatchesMeasured   = TotalMicrocodeSize;
+
+  MicrocodePatchesBlob = AllocateZeroPool (TotalMicrocodeSize);
+  if (NULL == MicrocodePatchesBlob) {
+    DEBUG ((DEBUG_ERROR, "ERROR: AllocateZeroPool to MicrocodePatchesBlob failed!\n"));
+    FreePool (Offsets);
+    return;
+  }
+
+  TotalMicrocodeSize = 0;
+  for (Index = 0; Index < Count; Index++) {
+    CopyMem (
+      (VOID *)(MicrocodePatchesBlob + TotalMicrocodeSize),
+      (VOID *)((UINTN)(MicrocodePatchHob->MicrocodePatchAddress + Offsets[Index])),
+      (UINTN)(GetMicrocodeLength (
+                (CPU_MICROCODE_HEADER *)((UINTN)(MicrocodePatchHob->MicrocodePatchAddress +
+                                                 Offsets[Index]))
+                ))
+      );
+    TotalMicrocodeSize +=
+      GetMicrocodeLength ((CPU_MICROCODE_HEADER *)((UINTN)(MicrocodePatchHob->MicrocodePatchAddress + Offsets[Index])));
+  }
+
+  Status = TpmMeasureAndLogData (
+             PCRIndex,                                 // PCRIndex
+             EventType,                                // EventType
+             &EventLog,                                // EventLog
+             EventLogSize,                             // LogLen
+             MicrocodePatchesBlob,                     // HashData
+             TotalMicrocodeSize                        // HashDataLen
+             );
+  if (!EFI_ERROR (Status)) {
+    gBS->CloseEvent (Event);
+    DEBUG (
+      (DEBUG_INFO,
+       "INFO: %d Microcode patches are successfully extended to TPM! The total size measured to TPM is 0x%x\n",
+       Count,
+       TotalMicrocodeSize)
+      );
+  } else {
+    DEBUG ((DEBUG_ERROR, "ERROR: TpmMeasureAndLogData failed with status %a!\n", Status));
+  }
+
+  FreePool (Offsets);
+  FreePool (MicrocodePatchesBlob);
+  return;
+}
+
+/**
+
+  Driver to produce microcode measurement.
+
+  Driver to produce microcode measurement. Which install a callback function on ready to boot event.
+
+  @param ImageHandle     Module's image handle
+  @param SystemTable     Pointer of EFI_SYSTEM_TABLE
+
+  @return EFI_SUCCESS     This function always complete successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+MicrocodeMeasurementDriverEntryPoint (
+  IN EFI_HANDLE        ImageHandle,
+  IN EFI_SYSTEM_TABLE  *SystemTable
+  )
+{
+  EFI_EVENT  Event;
+
+  //
+  // Measure Microcode patches
+  //
+  EfiCreateEventReadyToBootEx (
+    TPL_CALLBACK,
+    MeasureMicrocodePatches,
+    NULL,
+    &Event
+    );
+
+  return EFI_SUCCESS;
+}
diff --git a/UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxe.inf b/UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxe.inf
new file mode 100644
index 000000000000..649fb9403fd2
--- /dev/null
+++ b/UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxe.inf
@@ -0,0 +1,56 @@
+## @file
+#  This driver measures microcode patches to TPM.
+#
+#  This driver consumes gEdkiiMicrocodePatchHobGuid, packs all unique
+#  microcode patch found in gEdkiiMicrocodePatchHobGuid to a binary blob,
+#  and measures the binary blob to TPM.
+#
+#  Copyright (c) 2021, Intel Corporation. All rights reserved.<BR>
+#
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010005
+  BASE_NAME                      = MicrocodeMeasurementDxe
+  MODULE_UNI_FILE                = MicrocodeMeasurementDxe.uni
+  FILE_GUID                      = 0A32A803-ACDF-4C89-8293-91011548CD91
+  MODULE_TYPE                    = DXE_DRIVER
+  VERSION_STRING                 = 1.0
+  ENTRY_POINT                    = MicrocodeMeasurementDriverEntryPoint
+
+#
+# The following information is for reference only and not required by the build tools.
+#
+#  VALID_ARCHITECTURES           = IA32 X64
+#
+
+[Sources]
+  MicrocodeMeasurementDxe.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+  UefiCpuPkg/UefiCpuPkg.dec
+
+[LibraryClasses]
+  UefiBootServicesTableLib
+  MemoryAllocationLib
+  BaseMemoryLib
+  BaseLib
+  UefiLib
+  UefiDriverEntryPoint
+  DebugLib
+  HobLib
+  MicrocodeLib
+  TpmMeasurementLib
+
+[Guids]
+  gEdkiiMicrocodePatchHobGuid           ## CONSUMES ## HOB
+
+[UserExtensions.TianoCore."ExtraFiles"]
+  MicrocodeMeasurementDxeExtra.uni
+
+[Depex]
+  TRUE
diff --git a/UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxe.uni b/UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxe.uni
new file mode 100644
index 000000000000..5a21e955fbbf
--- /dev/null
+++ b/UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxe.uni
@@ -0,0 +1,15 @@
+// /** @file
+// This driver measures microcode patches to TPM.
+//
+// This driver consumes gEdkiiMicrocodePatchHobGuid, packs all uniquemicrocode patch found in gEdkiiMicrocodePatchHobGuid to a binary blob, and measures the binary blob to TPM.
+//
+// Copyright (c) 2021, Intel Corporation. All rights reserved.<BR>
+//
+// SPDX-License-Identifier: BSD-2-Clause-Patent
+//
+// **/
+
+
+#string STR_MODULE_ABSTRACT             #language en-US "This driver measures Microcode Patches to TPM."
+
+#string STR_MODULE_DESCRIPTION          #language en-US "This driver consumes gEdkiiMicrocodePatchHobGuid, packs all microcode patch found in gEdkiiMicrocodePatchHobGuid to a binary blob, and measure the binary blob to TPM."
diff --git a/UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxeExtra.uni b/UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxeExtra.uni
new file mode 100644
index 000000000000..6990cee8c6fd
--- /dev/null
+++ b/UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxeExtra.uni
@@ -0,0 +1,12 @@
+// /** @file
+// MicrocodeMeasurementDxe Localized Strings and Content
+//
+// Copyright (c) 2021, Intel Corporation. All rights reserved.<BR>
+//
+// SPDX-License-Identifier: BSD-2-Clause-Patent
+//
+// **/
+
+#string STR_PROPERTIES_MODULE_NAME
+#language en-US
+"Microcode Patches Measurement DXE Driver"
diff --git a/UefiCpuPkg/UefiCpuPkg.dsc b/UefiCpuPkg/UefiCpuPkg.dsc
index 870b45284087..d1d61dd6a03b 100644
--- a/UefiCpuPkg/UefiCpuPkg.dsc
+++ b/UefiCpuPkg/UefiCpuPkg.dsc
@@ -119,6 +119,7 @@
   UefiCpuPkg/Library/CpuTimerLib/BaseCpuTimerLib.inf
   UefiCpuPkg/Library/CpuCacheInfoLib/PeiCpuCacheInfoLib.inf
   UefiCpuPkg/Library/CpuCacheInfoLib/DxeCpuCacheInfoLib.inf
+  UefiCpuPkg/MicrocodeMeasurementDxe/MicrocodeMeasurementDxe.inf
 
 [Components.IA32, Components.X64]
   UefiCpuPkg/CpuDxe/CpuDxe.inf
-- 
2.31.1.windows.1