audk/MdePkg/Library/DxePiLib/DxePiLib.c

/** @file
  Mde PI library functions.

  Copyright (c) 2007, Intel Corporation<BR>
  All rights reserved. This program and the accompanying materials
  are licensed and made available under the terms and conditions of the BSD License
  which accompanies this distribution.  The full text of the license may be found at
  http://opensource.org/licenses/bsd-license.php

  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#include <PiDxe.h>
#include <Library/DebugLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/DxePiLib.h>
#include <Protocol/FirmwareVolume2.h>
#include <Protocol/LoadedImage.h>


/**
  Identify the device handle from which the Image is loaded from. As this device handle is passed to
  GetSectionFromFv as the identifier for a Firmware Volume, an EFI_FIRMWARE_VOLUME2_PROTOCOL 
  protocol instance should be located succesfully by calling gBS->HandleProtocol ().

  This function locates the EFI_LOADED_IMAGE_PROTOCOL instance installed
  on ImageHandle. It then returns EFI_LOADED_IMAGE_PROTOCOL.DeviceHandle.
  
  If ImageHandle is NULL, then ASSERT ();
  If failed to locate a EFI_LOADED_IMAGE_PROTOCOL on ImageHandle, then ASSERT ();
  
  @param  ImageHandle         The firmware allocated handle for UEFI image.

  @retval  EFI_HANDLE	        The device handle from which the Image is loaded from.

**/
EFI_HANDLE
InternalImageHandleToFvHandle (
  EFI_HANDLE ImageHandle
  )
{
  EFI_STATUS                    Status;
  EFI_LOADED_IMAGE_PROTOCOL     *LoadedImage;
  
  ASSERT (ImageHandle != NULL);

  Status = gBS->HandleProtocol (
             (EFI_HANDLE *) ImageHandle,
             &gEfiLoadedImageProtocolGuid,
             (VOID **) &LoadedImage
             );

  ASSERT_EFI_ERROR (Status);

  return LoadedImage->DeviceHandle;

}

/**
    Allocate and fill a buffer from a Firmware Section identified by a Firmware File GUID name, a Firmware 
    Section type and instance number from the specified Firmware Volume.
  
    This functions first locate the EFI_FIRMWARE_VOLUME2_PROTOCOL protocol instance on FvHandle in order to 
    carry out the Firmware Volume read operation. The function then reads the Firmware Section found sepcifed 
    by NameGuid, SectionType and Instance. 
    
    The search order for the section specified by SectionType within a Firmware File is defined by
    EFI_FIRMWARE_VOLUME2_PROTOCOL.ReadSection (). Please check Section 2.4 of Volume 3: Platform Initialization 
    Shared Architectural Elements for detailes.
    
    If SectionType is EFI_SECTION_TE, EFI_SECTION_TE will be used as Firmware Section type to read Firmware Section 
    data from the Firmware File. If no such section exists, EFI_SECTION_PE32 will be used as Firmware Section type to 
    read Firmware Section data from the Firmware File. If no such section specified is found to match , 
    EFI_NOT_FOUND is returned.
    
    The data and size is returned by Buffer and Size. The caller is responsible to free the Buffer allocated 
    by this function. This function can be only called at TPL_NOTIFY and below.
    
    If FvHandle is NULL, then ASSERT ();
    If NameGuid is NULL, then ASSERT();
    If Buffer is NULL, then ASSERT();
    If Size is NULL, then ASSERT().

    @param  FvHandle              The device handle that contains a instance of EFI_FIRMWARE_VOLUME2_PROTOCOL instance.
    @param  NameGuid             The GUID name of a Firmware File.
    @param  SectionType         The Firmware Section type.
    @param  Instance              The instance number of Firmware Section to read from starting from 0.
    @param  Buffer                  On output, Buffer contains the the data read from the section in the Firmware File found.
    @param  Size                    On output, the size of Buffer.
  
    @retval  EFI_SUCCESS        The image is found and data and size is returned.
    @retval  EFI_UNSUPPORTED   FvHandle does not support EFI_FIRMWARE_VOLUME2_PROTOCOL.
    @retval  EFI_NOT_FOUND      The image specified by NameGuid and SectionType can't be found.
    @retval  EFI_OUT_OF_RESOURCES There were not enough resources to allocate the output data buffer or complete the operations.
    @retval  EFI_DEVICE_ERROR A hardware error occurs during reading from the Firmware Volume.
    @retval  EFI_ACCESS_DENIED  The firmware volume containing the searched Firmware File is configured to disallow reads.
  
  **/


EFI_STATUS
GetSectionFromFv (
  IN  EFI_HANDLE                    FvHandle,
  IN  CONST EFI_GUID                *NameGuid,
  IN  EFI_SECTION_TYPE              SectionType,
  IN  UINTN                         Instance,
  OUT VOID                          **Buffer,
  OUT UINTN                         *Size
  )
{
  EFI_STATUS                    Status;
  EFI_FIRMWARE_VOLUME2_PROTOCOL *Fv;
  UINT32                        AuthenticationStatus;

  ASSERT (FvHandle != NULL);

  Status = gBS->HandleProtocol (
                  FvHandle,
                  &gEfiFirmwareVolume2ProtocolGuid,
                  (VOID **) &Fv
                  );
  if (EFI_ERROR (Status)) {
    return Status;
  }

  //
  // Read desired section content in NameGuid file
  //
  *Buffer     = NULL;
  *Size       = 0;
  Status      = Fv->ReadSection (
                      Fv,
                      NameGuid,
                      SectionType,
                      0,
                      Buffer,
                      Size,
                      &AuthenticationStatus
                      );

  if (EFI_ERROR (Status) && (SectionType == EFI_SECTION_TE)) {
    //
    // Try reading PE32 section, if the required section is TE type 
    //
    *Buffer = NULL;
    *Size   = 0;
    Status  = Fv->ReadSection (
                    Fv,
                    NameGuid,
                    EFI_SECTION_PE32,
                    0,
                    Buffer,
                    Size,
                    &AuthenticationStatus
                    );
  }

  return Status;
}



EFI_STATUS
EFIAPI
PiLibGetSectionFromAnyFv (
  IN CONST  EFI_GUID           *NameGuid,
  IN        EFI_SECTION_TYPE   SectionType,
  IN        UINTN              Instance,
  OUT       VOID               **Buffer,
  OUT       UINTN              *Size
  )
{
  EFI_STATUS                    Status;
  EFI_HANDLE                    *HandleBuffer;
  UINTN                         HandleCount;
  UINTN                         Index;
  EFI_HANDLE                    FvHandle;
  EFI_TPL                       OldTpl;

  //
  // Search the FV that contain the caller's FFS first.
  // FV builder can choose to build FFS into the this FV
  // so that this implementation of GetSectionFromAnyFv
  // will locate the FFS faster.
  //
  FvHandle = InternalImageHandleToFvHandle (gImageHandle);
  Status = GetSectionFromFv (
             FvHandle,
             NameGuid,
             SectionType,
             Instance,
             Buffer,
             Size
             );
  if (!EFI_ERROR (Status)) {
    return EFI_SUCCESS;
  }

  OldTpl = gBS->RaiseTPL (TPL_NOTIFY);
  
  HandleBuffer = NULL;
  Status = gBS->LocateHandleBuffer (
                  ByProtocol,
                  &gEfiFirmwareVolume2ProtocolGuid,
                  NULL,
                  &HandleCount,
                  &HandleBuffer
                  );
  if (EFI_ERROR (Status)) {
    goto Done;
  }

  for (Index = 0; Index < HandleCount; ++Index) {
    //
    // Skip the FV that contain the caller's FFS
    //
    if (HandleBuffer[Index] == FvHandle) {
      continue;
    }

    Status = GetSectionFromFv (
               HandleBuffer[Index], 
               NameGuid, 
               SectionType, 
               Instance,
               Buffer, 
               Size
               );

    if (!EFI_ERROR (Status)) {
      goto Done;
    }
  }

  if (Index == HandleCount) {
    Status = EFI_NOT_FOUND;
  }

Done:
  
  gBS->RestoreTPL (OldTpl);
  
  if (HandleBuffer != NULL) {  
    FreePool(HandleBuffer);
  }
  return Status;
  
}


EFI_STATUS
EFIAPI
PiLibGetSectionFromCurrentFv (
  IN  CONST EFI_GUID                *NameGuid,
  IN  EFI_SECTION_TYPE              SectionType,
  IN  UINTN                         Instance,
  OUT VOID                          **Buffer,
  OUT UINTN                         *Size
    )
{
  return GetSectionFromFv(
          InternalImageHandleToFvHandle(gImageHandle),
          NameGuid,
          SectionType,
          Instance,
          Buffer,
          Size
          );
}



EFI_STATUS
EFIAPI
PiLibGetSectionFromCurrentFfs (
  IN  EFI_SECTION_TYPE              SectionType,
  IN  UINTN                         Instance,
  OUT VOID                          **Buffer,
  OUT UINTN                         *Size
    )
{
  return GetSectionFromFv(
          InternalImageHandleToFvHandle(gImageHandle),
          &gEfiCallerIdGuid,
          SectionType,
          Instance,
          Buffer,
          Size
          );
}