UefiPayloadPkg/BlSupportPei: Validate NV FVH and set boot mode accord…

…ingly Signed-off-by: Michał Żygowski <[email protected]>
Dasharo · Oct 24, 2023 · 6c3dbe2 · 6c3dbe2
1 parent 8fc1c21
commit 6c3dbe2
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diff --git a/UefiPayloadPkg/BlSupportPei/BlSupportPei.c b/UefiPayloadPkg/BlSupportPei/BlSupportPei.c
@@ -392,6 +392,109 @@ MemInfoCallback (
   return EFI_SUCCESS;
 }
 
+/**
+  Check the integrity of firmware volume header.
+
+  @retval  EFI_SUCCESS   - The firmware volume is consistent
+  @retval  EFI_NOT_FOUND - The firmware volume has been corrupted.
+
+**/
+EFI_STATUS
+ValidateFvHeader (
+  SMMSTORE_INFO *SmmStoreInfo
+  )
+{
+  UINT16                      Checksum;
+  EFI_FIRMWARE_VOLUME_HEADER  *FwVolHeader;
+  VARIABLE_STORE_HEADER       *VariableStoreHeader;
+  UINTN                       VariableStoreLength;
+  UINTN                       FvLength;
+  UINT32                      NvStorageSize;
+  UINT32                      NvVariableSize;
+  UINT32                      FtwWorkingSize;
+  UINT32                      FtwSpareSize;
+
+
+  NvStorageSize = SmmStoreInfo->NumBlocks * SmmStoreInfo->BlockSize;
+  FtwSpareSize   = (SmmStoreInfo->NumBlocks / 2) * SmmStoreInfo->BlockSize;
+  FtwWorkingSize = SmmStoreInfo->BlockSize;
+  NvVariableSize = NvStorageSize - FtwSpareSize - FtwWorkingSize;
+
+  FwVolHeader        = (EFI_FIRMWARE_VOLUME_HEADER *)(UINTN)SmmStoreInfo->MmioAddress;
+  if (!FwVolHeader) {
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+
+  FvLength = FtwSpareSize + FtwWorkingSize + NvVariableSize;
+
+  //
+  // Verify the header revision, header signature, length
+  // Length of FvBlock cannot be 2**64-1
+  // HeaderLength cannot be an odd number
+  //
+  if (  (FwVolHeader->Revision  != EFI_FVH_REVISION)
+     || (FwVolHeader->Signature != EFI_FVH_SIGNATURE)
+     || (FwVolHeader->FvLength  != FvLength)
+        )
+  {
+    DEBUG ((
+      DEBUG_INFO,
+      "%a: No Firmware Volume header present\n",
+      __FUNCTION__
+      ));
+    return EFI_NOT_FOUND;
+  }
+
+  // Check the Firmware Volume Guid
+  if ( CompareGuid (&FwVolHeader->FileSystemGuid, &gEfiSystemNvDataFvGuid) == FALSE ) {
+    DEBUG ((
+      DEBUG_INFO,
+      "%a: Firmware Volume Guid non-compatible\n",
+      __FUNCTION__
+      ));
+    return EFI_NOT_FOUND;
+  }
+
+  // Verify the header checksum
+  Checksum = CalculateSum16 ((UINT16 *)FwVolHeader, FwVolHeader->HeaderLength);
+  if (Checksum != 0) {
+    DEBUG ((
+      DEBUG_INFO,
+      "%a: FV checksum is invalid (Checksum:0x%X)\n",
+      __FUNCTION__,
+      Checksum
+      ));
+    return EFI_NOT_FOUND;
+  }
+
+  VariableStoreHeader = (VARIABLE_STORE_HEADER *)(UINTN)(SmmStoreInfo->MmioAddress + FwVolHeader->HeaderLength);
+
+  // Check the Variable Store Guid
+  if (!CompareGuid (&VariableStoreHeader->Signature, &gEfiVariableGuid) &&
+      !CompareGuid (&VariableStoreHeader->Signature, &gEfiAuthenticatedVariableGuid))
+  {
+    DEBUG ((
+      DEBUG_INFO,
+      "%a: Variable Store Guid non-compatible\n",
+      __FUNCTION__
+      ));
+    return EFI_NOT_FOUND;
+  }
+
+  VariableStoreLength = NvVariableSize - FwVolHeader->HeaderLength;
+  if (VariableStoreHeader->Size != VariableStoreLength) {
+    DEBUG ((
+      DEBUG_INFO,
+      "%a: Variable Store Length does not match\n",
+      __FUNCTION__
+      ));
+    return EFI_NOT_FOUND;
+  }
+
+  return EFI_SUCCESS;
+}
+
 /**
   This is the entrypoint of PEIM
 
@@ -582,6 +685,17 @@ BlPeiEntryPoint (
     ASSERT (NewSMMSTOREInfo != NULL);
     CopyMem (NewSMMSTOREInfo, &SMMSTOREInfo, sizeof (SMMSTOREInfo));
     DEBUG ((DEBUG_INFO, "Created SMMSTORE info hob\n"));
+
+    Status = ValidateFvHeader (&SMMSTOREInfo);
+    if (EFI_ERROR (Status)) {
+      Status = PeiServicesSetBootMode (BOOT_WITH_DEFAULT_SETTINGS);
+      DEBUG ((DEBUG_INFO, "BootMode: Boot with default settings\n"));
+      ASSERT_EFI_ERROR (Status);
+    } else {
+      Status = PeiServicesSetBootMode (BOOT_ASSUMING_NO_CONFIGURATION_CHANGES);
+      DEBUG ((DEBUG_INFO, "BootMode: Boot boot assuming no configuration changes\n"));
+      ASSERT_EFI_ERROR (Status);
+    }
   }
 
   //

diff --git a/UefiPayloadPkg/BlSupportPei/BlSupportPei.h b/UefiPayloadPkg/BlSupportPei/BlSupportPei.h
@@ -23,6 +23,9 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 #include <Library/IoLib.h>
 #include <Library/PlatformSupportLib.h>
 #include <IndustryStandard/Acpi.h>
+#include <Guid/VariableFormat.h>
+#include <Guid/SystemNvDataGuid.h>
+#include <Guid/NvVarStoreFormatted.h>
 #include <Guid/MemoryTypeInformation.h>
 #include <Guid/FirmwareFileSystem2.h>
 #include <Guid/SystemTableInfoGuid.h>

diff --git a/UefiPayloadPkg/BlSupportPei/BlSupportPei.inf b/UefiPayloadPkg/BlSupportPei/BlSupportPei.inf
@@ -31,6 +31,7 @@
 [Packages]
   MdePkg/MdePkg.dec
   MdeModulePkg/MdeModulePkg.dec
+  EmbeddedPkg/EmbeddedPkg.dec
   IntelFsp2Pkg/IntelFsp2Pkg.dec
   IntelFsp2WrapperPkg/IntelFsp2WrapperPkg.dec
   UefiPayloadPkg/UefiPayloadPkg.dec
@@ -59,6 +60,10 @@
   gEfiSmmStoreInfoHobGuid
   gEfiTcgPhysicalPresenceInfoHobGuid
   gEfiFirmwarePerformanceGuid
+  gEfiSystemNvDataFvGuid
+  gEfiVariableGuid
+  gEfiAuthenticatedVariableGuid
+  gEdkiiNvVarStoreFormattedGuid
 
 [Ppis]
   gEfiPeiMasterBootModePpiGuid