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MdeModulePkg/SecurityStubDxe: Defer 3rd party image before EndOfDxe
The images not from FV are treated as 3rd party images. They will be deferred to dispatch when they are dispatched before EndOfDxe event. It's a new feature in the BS.LoadImage() path which can disallow executing 3rd party images before EndOfDxe and re-execute them after EndOfDxe (through EfiBootManagerDispatchDeferredImages introduced in next commit). Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com> Reviewed-by: Liming Gao <liming.gao@intel.com> Cc: Jiewen Yao <jiewen.yao@intel.com> Reviewed-by: Chao B Zhang <chao.b.zhang@intel.com> Reviewed-by: Sunny Wang <sunnywang@hpe.com>
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/** @file
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Implement defer image load services for user identification in UEFI2.2.
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Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
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This program and the accompanying materials
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are licensed and made available under the terms and conditions of the BSD License
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which accompanies this distribution. The full text of the license may be found at
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http://opensource.org/licenses/bsd-license.php
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THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
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WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
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**/
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#include "Defer3rdPartyImageLoad.h"
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//
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// The structure to save the deferred 3rd party image information.
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//
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typedef struct {
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EFI_DEVICE_PATH_PROTOCOL *ImageDevicePath;
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BOOLEAN BootOption;
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BOOLEAN Loaded;
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} DEFERRED_3RD_PARTY_IMAGE_INFO;
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//
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// The table to save the deferred 3rd party image item.
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//
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typedef struct {
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UINTN Count; ///< deferred 3rd party image count
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DEFERRED_3RD_PARTY_IMAGE_INFO *ImageInfo; ///< deferred 3rd party image item
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} DEFERRED_3RD_PARTY_IMAGE_TABLE;
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BOOLEAN mEndOfDxe = FALSE;
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DEFERRED_3RD_PARTY_IMAGE_TABLE mDeferred3rdPartyImage = {
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0, // Deferred image count
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NULL // The deferred image info
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};
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EFI_DEFERRED_IMAGE_LOAD_PROTOCOL mDeferredImageLoad = {
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GetDefferedImageInfo
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};
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/**
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Return whether the file comes from FV.
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@param[in] File This is a pointer to the device path of the file
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that is being dispatched.
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@retval TRUE File comes from FV.
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@retval FALSE File doesn't come from FV.
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**/
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BOOLEAN
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FileFromFv (
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IN CONST EFI_DEVICE_PATH_PROTOCOL *File
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)
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{
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EFI_STATUS Status;
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EFI_HANDLE DeviceHandle;
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EFI_DEVICE_PATH_PROTOCOL *TempDevicePath;
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//
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// First check to see if File is from a Firmware Volume
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//
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DeviceHandle = NULL;
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TempDevicePath = (EFI_DEVICE_PATH_PROTOCOL *) File;
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Status = gBS->LocateDevicePath (
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&gEfiFirmwareVolume2ProtocolGuid,
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&TempDevicePath,
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&DeviceHandle
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);
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if (!EFI_ERROR (Status)) {
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Status = gBS->OpenProtocol (
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DeviceHandle,
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&gEfiFirmwareVolume2ProtocolGuid,
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NULL,
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NULL,
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NULL,
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EFI_OPEN_PROTOCOL_TEST_PROTOCOL
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);
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if (!EFI_ERROR (Status)) {
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return TRUE;
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}
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}
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return FALSE;
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}
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/**
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Find the deferred image which matches the device path.
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@param[in] ImageDevicePath A pointer to the device path of a image.
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@param[in] BootOption Whether the image is a boot option.
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@return Pointer to the found deferred image or NULL if not found.
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**/
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DEFERRED_3RD_PARTY_IMAGE_INFO *
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LookupImage (
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IN CONST EFI_DEVICE_PATH_PROTOCOL *ImageDevicePath,
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IN BOOLEAN BootOption
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)
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{
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UINTN Index;
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UINTN DevicePathSize;
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DevicePathSize = GetDevicePathSize (ImageDevicePath);
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for (Index = 0; Index < mDeferred3rdPartyImage.Count; Index++) {
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if (CompareMem (ImageDevicePath, mDeferred3rdPartyImage.ImageInfo[Index].ImageDevicePath, DevicePathSize) == 0) {
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ASSERT (mDeferred3rdPartyImage.ImageInfo[Index].BootOption == BootOption);
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return &mDeferred3rdPartyImage.ImageInfo[Index];
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}
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}
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return NULL;
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}
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/**
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Add the image info to a deferred image list.
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@param[in] ImageDevicePath A pointer to the device path of a image.
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@param[in] BootOption Whether the image is a boot option.
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**/
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VOID
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QueueImage (
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IN CONST EFI_DEVICE_PATH_PROTOCOL *ImageDevicePath,
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IN BOOLEAN BootOption
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)
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{
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DEFERRED_3RD_PARTY_IMAGE_INFO *ImageInfo;
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//
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// Expand memory for the new deferred image.
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//
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ImageInfo = ReallocatePool (
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mDeferred3rdPartyImage.Count * sizeof (DEFERRED_3RD_PARTY_IMAGE_INFO),
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(mDeferred3rdPartyImage.Count + 1) * sizeof (DEFERRED_3RD_PARTY_IMAGE_INFO),
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mDeferred3rdPartyImage.ImageInfo
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);
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if (ImageInfo == NULL) {
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return;
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}
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mDeferred3rdPartyImage.ImageInfo = ImageInfo;
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//
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// Save the deferred image information.
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//
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ImageInfo = &mDeferred3rdPartyImage.ImageInfo[mDeferred3rdPartyImage.Count];
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ImageInfo->ImageDevicePath = DuplicateDevicePath (ImageDevicePath);
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if (ImageInfo->ImageDevicePath == NULL) {
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return;
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}
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ImageInfo->BootOption = BootOption;
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ImageInfo->Loaded = FALSE;
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mDeferred3rdPartyImage.Count++;
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}
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/**
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Returns information about a deferred image.
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This function returns information about a single deferred image. The deferred images are
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numbered consecutively, starting with 0. If there is no image which corresponds to
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ImageIndex, then EFI_NOT_FOUND is returned. All deferred images may be returned by
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iteratively calling this function until EFI_NOT_FOUND is returned.
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Image may be NULL and ImageSize set to 0 if the decision to defer execution was made
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because of the location of the executable image, rather than its actual contents.
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@param[in] This Points to this instance of the EFI_DEFERRED_IMAGE_LOAD_PROTOCOL.
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@param[in] ImageIndex Zero-based index of the deferred index.
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@param[out] ImageDevicePath On return, points to a pointer to the device path of the image.
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The device path should not be freed by the caller.
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@param[out] Image On return, points to the first byte of the image or NULL if the
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image is not available. The image should not be freed by the caller
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unless LoadImage() has been successfully called.
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@param[out] ImageSize On return, the size of the image, or 0 if the image is not available.
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@param[out] BootOption On return, points to TRUE if the image was intended as a boot option
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or FALSE if it was not intended as a boot option.
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@retval EFI_SUCCESS Image information returned successfully.
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@retval EFI_NOT_FOUND ImageIndex does not refer to a valid image.
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@retval EFI_INVALID_PARAMETER ImageDevicePath is NULL or Image is NULL or ImageSize is NULL or
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BootOption is NULL.
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**/
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EFI_STATUS
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EFIAPI
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GetDefferedImageInfo (
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IN EFI_DEFERRED_IMAGE_LOAD_PROTOCOL *This,
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IN UINTN ImageIndex,
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OUT EFI_DEVICE_PATH_PROTOCOL **ImageDevicePath,
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OUT VOID **Image,
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OUT UINTN *ImageSize,
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OUT BOOLEAN *BootOption
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)
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{
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UINTN Index;
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UINTN NewCount;
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if ((This == NULL) || (ImageSize == NULL) || (Image == NULL)) {
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return EFI_INVALID_PARAMETER;
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}
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if ((ImageDevicePath == NULL) || (BootOption == NULL)) {
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return EFI_INVALID_PARAMETER;
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}
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//
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// Remove the loaded images from the defer list in the first call.
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//
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if (ImageIndex == 0) {
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NewCount = 0;
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for (Index = 0; Index < mDeferred3rdPartyImage.Count; Index++) {
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if (!mDeferred3rdPartyImage.ImageInfo[Index].Loaded) {
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CopyMem (
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&mDeferred3rdPartyImage.ImageInfo[NewCount],
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&mDeferred3rdPartyImage.ImageInfo[Index],
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sizeof (DEFERRED_3RD_PARTY_IMAGE_INFO)
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);
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NewCount++;
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}
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}
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mDeferred3rdPartyImage.Count = NewCount;
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}
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if (ImageIndex >= mDeferred3rdPartyImage.Count) {
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return EFI_NOT_FOUND;
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}
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//
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// Get the request deferred image.
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//
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*ImageDevicePath = mDeferred3rdPartyImage.ImageInfo[ImageIndex].ImageDevicePath;
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*BootOption = mDeferred3rdPartyImage.ImageInfo[ImageIndex].BootOption;
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*Image = NULL;
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*ImageSize = 0;
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return EFI_SUCCESS;
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}
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/**
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Callback function executed when the EndOfDxe event group is signaled.
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@param[in] Event Event whose notification function is being invoked.
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@param[in] Context The pointer to the notification function's context, which
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is implementation-dependent.
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**/
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VOID
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EFIAPI
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EndOfDxe (
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IN EFI_EVENT Event,
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IN VOID *Context
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)
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{
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mEndOfDxe = TRUE;
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}
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/**
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Defer the 3rd party image load and installs Deferred Image Load Protocol.
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@param[in] File This is a pointer to the device path of the file that
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is being dispatched. This will optionally be used for
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logging.
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@param[in] BootPolicy A boot policy that was used to call LoadImage() UEFI service.
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@retval EFI_SUCCESS The file is not 3rd party image and can be loaded immediately.
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@retval EFI_ACCESS_DENIED The file is 3rd party image and needs deferred.
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**/
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EFI_STATUS
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Defer3rdPartyImageLoad (
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IN CONST EFI_DEVICE_PATH_PROTOCOL *File,
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IN BOOLEAN BootPolicy
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)
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{
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DEFERRED_3RD_PARTY_IMAGE_INFO *ImageInfo;
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//
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// Ignore if File is NULL.
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//
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if (File == NULL) {
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return EFI_SUCCESS;
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}
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if (FileFromFv (File)) {
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return EFI_SUCCESS;
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}
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ImageInfo = LookupImage (File, BootPolicy);
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DEBUG_CODE (
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CHAR16 *DevicePathStr;
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DevicePathStr = ConvertDevicePathToText (File, FALSE, FALSE);
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DEBUG ((
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DEBUG_INFO,
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"[Security] 3rd party image[%p] %s EndOfDxe: %s.\n", ImageInfo,
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mEndOfDxe ? L"can be loaded after": L"is deferred to load before",
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DevicePathStr
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));
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if (DevicePathStr != NULL) {
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FreePool (DevicePathStr);
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}
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);
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if (mEndOfDxe) {
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//
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// The image might be first time loaded after EndOfDxe,
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// So ImageInfo can be NULL.
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//
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if (ImageInfo != NULL) {
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ImageInfo->Loaded = TRUE;
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}
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return EFI_SUCCESS;
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} else {
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//
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// The image might be second time loaded before EndOfDxe,
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// So ImageInfo can be non-NULL.
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//
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if (ImageInfo == NULL) {
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QueueImage (File, BootPolicy);
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}
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return EFI_ACCESS_DENIED;
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}
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}
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/**
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Installs DeferredImageLoad Protocol and listens EndOfDxe event.
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**/
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VOID
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Defer3rdPartyImageLoadInitialize (
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VOID
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)
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{
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EFI_STATUS Status;
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EFI_HANDLE Handle;
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EFI_EVENT Event;
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Handle = NULL;
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Status = gBS->InstallMultipleProtocolInterfaces (
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&Handle,
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&gEfiDeferredImageLoadProtocolGuid,
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&mDeferredImageLoad,
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NULL
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);
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ASSERT_EFI_ERROR (Status);
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Status = gBS->CreateEventEx (
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EVT_NOTIFY_SIGNAL,
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TPL_CALLBACK,
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EndOfDxe,
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NULL,
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&gEfiEndOfDxeEventGroupGuid,
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&Event
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);
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ASSERT_EFI_ERROR (Status);
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}

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