Publish EDK's TPM eventlog that contains coreboot's entries

DasharoModulePkg/Library/DasharoVariablesLib/DasharoVariablesLib.c

@@ -338,6 +338,27 @@ MeasureVariable (
   return Status;
 }
 
+/**
+  A comparison function for sorting an array of variable names.
+
+  @param Buffer1  Pointer to pointer of the first variable name.
+  @param Buffer2  Pointer to pointer of the second variable name.
+
+  @retval <0  The first variable name is less than the second one.
+  @retval =0  The names are equal.
+  @retval >0  The first variable name is greater than the second one.
+**/
+STATIC
+INTN
+EFIAPI
+CompareVariableNames (
+  IN CONST VOID  *Buffer1,
+  IN CONST VOID  *Buffer2
+  )
+{
+  return StrCmp (*(CONST CHAR16 **) Buffer1, *(CONST CHAR16 **) Buffer2);
+}
+
 /**
   Measures single all existing variables with the specified GUID.
 
@@ -357,12 +378,25 @@ MeasureVariables (
   UINTN       MaxNameSize;
   UINTN       NameSize;
   EFI_GUID    Guid;
+  CHAR16      **Names;
+  UINTN       NameCount;
+  CHAR16      SortBuf;
+  UINTN       MaxNameCount;
+  UINTN       Index;
 
-  MaxNameSize = 32*sizeof (CHAR16);
+  MaxNameSize = 32 * sizeof (CHAR16);
   Name = AllocateZeroPool (MaxNameSize);
   if (Name == NULL)
     return EFI_OUT_OF_RESOURCES;
 
+  MaxNameCount = 32;
+  NameCount = 0;
+  Names = AllocatePool (MaxNameCount * sizeof (*Names));
+  if (Names == NULL) {
+    FreePool(Name);
+    return EFI_OUT_OF_RESOURCES;
+  }
+
   while (TRUE) {
     NameSize = MaxNameSize;
     Status = gRT->GetNextVariableName (&NameSize, Name, &Guid);
@@ -373,7 +407,7 @@ MeasureVariables (
         break;
       }
 
-      StrnCpyS (NewBuf, NameSize/sizeof (CHAR16), Name, MaxNameSize/sizeof (CHAR16));
+      StrnCpyS (NewBuf, NameSize / sizeof (CHAR16), Name, MaxNameSize / sizeof (CHAR16));
       FreePool (Name);
 
       Name = NewBuf;
@@ -390,11 +424,59 @@ MeasureVariables (
     if (EFI_ERROR (Status))
       break;
 
-    if (CompareGuid (&Guid, Vendor))
-      MeasureVariable (Name, Vendor);
+    if (!CompareGuid (&Guid, Vendor))
+      continue;
+
+    if (NameCount == MaxNameCount - 1) {
+      Names = ReallocatePool (
+          MaxNameCount * sizeof (*Names),
+          2 * MaxNameCount * sizeof (*Names),
+          Names
+          );
+      if (Names == NULL) {
+        Status = EFI_OUT_OF_RESOURCES;
+        break;
+      }
+
+      MaxNameCount *= 2;
+    }
+
+    Names[NameCount] = AllocateCopyPool (NameSize, Name);
+    if (Names[NameCount] == NULL) {
+      Status = EFI_OUT_OF_RESOURCES;
+      break;
+    }
+
+    NameCount++;
   }
 
+  if (Status == EFI_SUCCESS) {
+    //
+    // Achieve predictable ordering of variables by sorting them by name within
+    // a particular vendor.
+    //
+    QuickSort (
+        Names,
+        NameCount,
+        sizeof (*Names),
+        CompareVariableNames,
+        &SortBuf
+        );
+
+    for (Index = 0; Index < NameCount; Index++) {
+      Status = MeasureVariable (Names[Index], Vendor);
+      if (EFI_ERROR (Status)) {
+        DEBUG ((EFI_D_WARN, "%a(): Failed to measure variable: %g:%s.\n",
+                __FUNCTION__, Vendor, Name));
+      }
+    }
+  }
+
+  for (Index = 0; Index < NameCount; Index++)
+    FreePool (Names[Index]);
+
   FreePool (Name);
+  FreePool (Names);
   return Status;
 }
 

DasharoPayloadPkg/BlSupportPei/BlSupportPei.c

@@ -8,6 +8,9 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 **/
 #include "BlSupportPei.h"
 
+#include <Coreboot.h>
+#include <IndustryStandard/UefiTcgPlatform.h>
+
 #define LEGACY_8259_MASK_REGISTER_MASTER  0x21
 #define LEGACY_8259_MASK_REGISTER_SLAVE   0xA1
 
@@ -496,6 +499,139 @@ ValidateFvHeader (
   return EFI_SUCCESS;
 }
 
+STATIC
+EFI_STATUS
+ParseAndPublishTPM1Log (
+  CONST struct tcpa_spec_entry  *SpecEntry,
+  UINTN                         Size
+)
+{
+  UINT8                  ZeroBlock[sizeof (struct tcpa_spec_entry)];
+  struct tcpa_log_entry  *Entry;
+  EFI_PHYSICAL_ADDRESS   Start;
+  EFI_PHYSICAL_ADDRESS   Current;
+  UINTN                  EntrySize;
+
+  // This must hold to avoid integer overflow below.
+  ASSERT (Size >= sizeof (*Entry));
+
+  ZeroMem (ZeroBlock, sizeof (ZeroBlock));
+
+  Start = (EFI_PHYSICAL_ADDRESS)(UINTN) SpecEntry;
+  Current = Start;
+  while (Current - Start < Size - sizeof (*Entry) &&
+         CompareMem ((VOID *)(UINTN) Current, (VOID *) ZeroBlock, sizeof (ZeroBlock)) != 0) {
+    Entry = (VOID *)(UINTN) Current;
+    EntrySize = sizeof (*Entry) + Entry->event_data_size;
+
+    BuildGuidDataHob (&gTcgEventEntryHobGuid, Entry, EntrySize);
+    Current += EntrySize;
+  }
+
+  return EFI_SUCCESS;
+}
+
+STATIC
+EFI_STATUS
+ParseAndPublishTPM2Log (
+  CONST struct tcg_efi_spec_id_event  *SpecEntry,
+  UINTN                               Size
+)
+{
+  UINT8                         ZeroBlock[sizeof (struct tcg_pcr_event2_header)];
+  struct tcg_pcr_event2_header  *Header;
+  EFI_PHYSICAL_ADDRESS          Start;
+  EFI_PHYSICAL_ADDRESS          Current;
+  UINTN                         EntrySize;
+  UINTN                         DigestsSize;
+  UINTN                         Idx;
+
+  // This must hold to avoid integer overflow below.
+  ASSERT (Size >= sizeof (*Header));
+
+  ZeroMem (ZeroBlock, sizeof (ZeroBlock));
+
+  DigestsSize = 0;
+  for (Idx = 0; Idx < SpecEntry->num_of_algorithms; ++Idx) {
+    DigestsSize += sizeof (UINT16) + SpecEntry->digest_sizes[Idx].digest_size;
+  }
+
+  Start = (EFI_PHYSICAL_ADDRESS)(UINTN) SpecEntry;
+
+  // Not adding Spec ID Event for TPM2 because Tcg2Dxe adds one, coreboot's
+  // event would have to be modified to be suitable due to the list of
+  // algorithms there.
+  Current = Start + sizeof (struct tcpa_log_entry) + SpecEntry->event_size;
+
+  while (Current - Start < Size - sizeof (*Header) &&
+         CompareMem ((VOID *)(UINTN) Current, (VOID *) ZeroBlock, sizeof (ZeroBlock)) != 0) {
+    Header = (VOID *)(UINTN) Current;
+    EntrySize = sizeof (*Header) + DigestsSize;
+
+    // Event data size field and data itself.
+    EntrySize += sizeof (UINT32) + *(CONST UINT32 *)(UINTN) (Current + EntrySize);
+
+    BuildGuidDataHob (&gTcgEvent2EntryHobGuid, Header, EntrySize);
+    Current += EntrySize;
+  }
+
+  return EFI_SUCCESS;
+}
+
+STATIC
+EFI_STATUS
+ParseAndPublishTPMLog (
+  VOID
+)
+{
+  RETURN_STATUS  Status;
+  VOID           *LogBase;
+  UINTN          LogSize;
+
+  const struct tcpa_spec_entry        *Tcg1Entry;
+  const struct tcg_efi_spec_id_event  *Tcg2Entry;
+
+  Status = ParseTPMLog (&LogBase, &LogSize);
+  if (EFI_ERROR (Status)) {
+    DEBUG ((
+      DEBUG_INFO,
+      "%a: Not publishing coreboot's TPM log entries because: %r.\n",
+      __FUNCTION__, Status
+      ));
+    return Status;
+  }
+
+  Tcg1Entry = LogBase;
+  if (AsciiStrCmp((CONST CHAR8 *)Tcg1Entry->signature, TCPA_SPEC_ID_EVENT_SIGNATURE) == 0) {
+    if (Tcg1Entry->spec_version_major == 1 &&
+        Tcg1Entry->spec_version_minor == 2 &&
+        Tcg1Entry->spec_errata >= 1 &&
+        Tcg1Entry->entry.event_type == EV_NO_ACTION) {
+      return ParseAndPublishTPM1Log (Tcg1Entry, LogSize);
+    }
+
+    DEBUG ((DEBUG_WARN, "%a: Unknown TPM1.2 log specification.\n", __FUNCTION__));
+    return EFI_UNSUPPORTED;
+  }
+
+  Tcg2Entry = LogBase;
+  if (AsciiStrCmp((CONST CHAR8 *)Tcg1Entry->signature, TCG_EFI_SPEC_ID_EVENT_SIGNATURE) == 0) {
+    if (Tcg2Entry->spec_version_major == 2 &&
+        Tcg2Entry->spec_version_minor == 0 &&
+        Tcg2Entry->event_type == EV_NO_ACTION) {
+      return ParseAndPublishTPM2Log (Tcg2Entry, LogSize);
+    }
+
+    DEBUG ((DEBUG_WARN, "%a: Unknown TPM2 log specification.\n", __FUNCTION__));
+    return EFI_UNSUPPORTED;
+  }
+
+  DEBUG ((DEBUG_WARN,
+          "%a: Unknown TPM log specification %.*s.\n",
+          __FUNCTION__, (int)sizeof(Tcg2Entry->signature), (CONST CHAR8 *)Tcg2Entry->signature));
+  return EFI_UNSUPPORTED;
+}
+
 /**
   This is the entrypoint of PEIM
 
@@ -767,6 +903,15 @@ BlPeiEntryPoint (
   IoWrite8 (LEGACY_8259_MASK_REGISTER_MASTER, 0xFF);
   IoWrite8 (LEGACY_8259_MASK_REGISTER_SLAVE,  0xFF);
 
+  //
+  // Parse coreboot's log.
+  //
+  Status = ParseAndPublishTPMLog ();
+  if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_ERROR, "Error when parsing platform info, Status = %r\n", Status));
+    return Status;
+  }
+
   return EFI_SUCCESS;
 }
 

DasharoPayloadPkg/BlSupportPei/BlSupportPei.inf

@@ -34,6 +34,7 @@
   EmbeddedPkg/EmbeddedPkg.dec
   IntelFsp2Pkg/IntelFsp2Pkg.dec
   IntelFsp2WrapperPkg/IntelFsp2WrapperPkg.dec
+  SecurityPkg/SecurityPkg.dec
   DasharoPayloadPkg/DasharoPayloadPkg.dec
   UefiCpuPkg/UefiCpuPkg.dec
 
@@ -64,6 +65,8 @@
   gEfiVariableGuid
   gEfiAuthenticatedVariableGuid
   gEdkiiNvVarStoreFormattedGuid
+  gTcgEventEntryHobGuid
+  gTcgEvent2EntryHobGuid
 
 [Ppis]
   gEfiPeiMasterBootModePpiGuid

DasharoPayloadPkg/Include/Coreboot.h

@@ -264,6 +264,7 @@ struct cb_smmstorev2 {
 	UINT8 unused[3];	/* Set to zero */
 };
 
+#define CB_TAG_CBMEM_ENTRY      0x0031
 #define CB_TAG_VBOOT_WORKBUF    0x0034
 
 struct cb_cbmem_entry {
@@ -762,4 +763,67 @@ struct cb_range {
 	UINT32 range_size;
 } __attribute__((packed));
 
+#define CBMEM_ID_TCPA_TCG_LOG 0x54445041 /* TPM log per TPM 1.2 specification */
+#define CBMEM_ID_TPM2_TCG_LOG 0x54504d32 /* TPM log per TPM 2.0 specification */
+
+#define TCPA_SPEC_ID_EVENT_SIGNATURE    "Spec ID Event00"
+#define TCG_EFI_SPEC_ID_EVENT_SIGNATURE "Spec ID Event03"
+
+struct tcpa_log_entry {
+  UINT32 pcr;
+  UINT32 event_type;
+  UINT8 digest[20];
+  UINT32 event_data_size;
+  UINT8 event[0];
+} __attribute__ ((packed));
+
+struct tcpa_spec_entry {
+  struct tcpa_log_entry entry;
+  UINT8 signature[16];
+  UINT32 platform_class;
+  UINT8 spec_version_minor;
+  UINT8 spec_version_major;
+  UINT8 spec_errata;
+  UINT8 reserved;
+  UINT8 vendor_info_size;
+  UINT8 vendor_info[0];
+} __attribute__ ((packed));
+
+#define TPM2_ALG_SHA1    0x0004
+#define TPM2_ALG_SHA256  0x000B
+#define TPM2_ALG_SHA384  0x000C
+#define TPM2_ALG_SHA512  0x000D
+#define TPM2_ALG_SM3_256 0x0012
+
+struct tcg_pcr_event2_header {
+  UINT32 pcr_index;
+  UINT32 event_type;
+  UINT32 digest_count;
+  UINT8 digests[0];
+  /* UINT32 event_size; */
+  /* UINT8 event[0]; */
+} __attribute__ ((packed));
+
+struct tpm_digest_sizes {
+  UINT16 alg_id;
+  UINT16 digest_size;
+} __attribute__ ((packed));
+
+struct tcg_efi_spec_id_event {
+  UINT32 pcr_index;
+  UINT32 event_type;
+  UINT8 digest[20];
+  UINT32 event_size;
+  UINT8 signature[16];
+  UINT32 platform_class;
+  UINT8 spec_version_minor;
+  UINT8 spec_version_major;
+  UINT8 spec_errata;
+  UINT8 uintn_size;
+  UINT32 num_of_algorithms;
+  struct tpm_digest_sizes digest_sizes[0]; /* variable number of members */
+  /* UINT8 vendor_info_size; */
+  /* UINT8 vendor_info[vendor_info_size]; */
+} __attribute__ ((packed));
+
 #endif // _COREBOOT_PEI_H_INCLUDED_