[PATCH 4/4] MdeModulePkg/UefiBootManagerLib: allow foreign Driver#### images

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

Allow PE/COFF images that must execute under emulation for Driver####
options, by relaxing the machine type check to include support for
machine types that is provided by the emulator.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 MdeModulePkg/Library/UefiBootManagerLib/BmLoadOption.c         | 26 +++++++++++++++++++-
 MdeModulePkg/Library/UefiBootManagerLib/InternalBm.h           |  1 +
 MdeModulePkg/Library/UefiBootManagerLib/UefiBootManagerLib.inf |  1 +
 3 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/MdeModulePkg/Library/UefiBootManagerLib/BmLoadOption.c b/MdeModulePkg/Library/UefiBootManagerLib/BmLoadOption.c
index 7bf96646c690..67e3dfd7e9e1 100644
--- a/MdeModulePkg/Library/UefiBootManagerLib/BmLoadOption.c
+++ b/MdeModulePkg/Library/UefiBootManagerLib/BmLoadOption.c
@@ -1185,6 +1185,29 @@ EfiBootManagerFreeLoadOptions (
   return EFI_SUCCESS;
 }
 
+STATIC
+BOOLEAN
+BmIsImageTypeSupported (
+  IN  UINT16    MachineType,
+  IN  UINT16    SubSystem
+  )
+{
+  EFI_STATUS                            Status;
+  EDKII_PECOFF_IMAGE_EMULATOR_PROTOCOL  *Emu;
+
+  if (EFI_IMAGE_MACHINE_TYPE_SUPPORTED (MachineType)) {
+    return TRUE;
+  }
+
+  Status = gBS->LocateProtocol (&gEdkiiPeCoffImageEmulatorProtocolGuid,
+                  NULL, (VOID **)&Emu);
+  if (EFI_ERROR (Status)) {
+    return FALSE;
+  }
+
+  return Emu->IsImageSupported (Emu, MachineType, SubSystem);
+}
+
 /**
   Return whether the PE header of the load option is valid or not.
 
@@ -1235,7 +1258,8 @@ BmIsLoadOptionPeHeaderValid (
       OptionalHeader = (EFI_IMAGE_OPTIONAL_HEADER32 *) &PeHeader->Pe32.OptionalHeader;
       if ((OptionalHeader->Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC ||
            OptionalHeader->Magic == EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC) &&
-          EFI_IMAGE_MACHINE_TYPE_SUPPORTED (PeHeader->Pe32.FileHeader.Machine)
+          BmIsImageTypeSupported (PeHeader->Pe32.FileHeader.Machine,
+                                  OptionalHeader->Subsystem)
           ) {
         //
         // Check the Subsystem:
diff --git a/MdeModulePkg/Library/UefiBootManagerLib/InternalBm.h b/MdeModulePkg/Library/UefiBootManagerLib/InternalBm.h
index 978fbff966f6..5f64ef304b87 100644
--- a/MdeModulePkg/Library/UefiBootManagerLib/InternalBm.h
+++ b/MdeModulePkg/Library/UefiBootManagerLib/InternalBm.h
@@ -47,6 +47,7 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 #include <Protocol/VariableLock.h>
 #include <Protocol/RamDisk.h>
 #include <Protocol/DeferredImageLoad.h>
+#include <Protocol/PeCoffImageEmulator.h>
 
 #include <Guid/MemoryTypeInformation.h>
 #include <Guid/FileInfo.h>
diff --git a/MdeModulePkg/Library/UefiBootManagerLib/UefiBootManagerLib.inf b/MdeModulePkg/Library/UefiBootManagerLib/UefiBootManagerLib.inf
index 72c5ca1cd59e..09e2134acf8e 100644
--- a/MdeModulePkg/Library/UefiBootManagerLib/UefiBootManagerLib.inf
+++ b/MdeModulePkg/Library/UefiBootManagerLib/UefiBootManagerLib.inf
@@ -104,6 +104,7 @@
   gEfiDevicePathProtocolGuid                    ## SOMETIMES_CONSUMES
   gEfiBootLogoProtocolGuid                      ## SOMETIMES_CONSUMES
   gEfiSimpleTextInputExProtocolGuid             ## SOMETIMES_CONSUMES
+  gEdkiiPeCoffImageEmulatorProtocolGuid         ## SOMETIMES_CONSUMES
   gEdkiiVariableLockProtocolGuid                ## SOMETIMES_CONSUMES
   gEfiGraphicsOutputProtocolGuid                ## SOMETIMES_CONSUMES
   gEfiUsbIoProtocolGuid                         ## SOMETIMES_CONSUMES
-- 
2.17.1