summaryrefslogtreecommitdiffstats
path: root/MdePkg/Library/DxeServicesLib/DxeServicesLib.c
blob: 0735b2f80400ce829a6e76c0e18f99fc2e9125cb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
/** @file
  MDE DXE Services Library provides functions that simplify the development of DXE Drivers.
  These functions help access data from sections of FFS files or from file path.

  Copyright (c) 2007 - 2018, Intel Corporation. All rights reserved.<BR>
  (C) Copyright 2015 Hewlett Packard Enterprise Development LP<BR>
  SPDX-License-Identifier: BSD-2-Clause-Patent

**/

#include <PiDxe.h>
#include <Library/DebugLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/DevicePathLib.h>
#include <Library/UefiLib.h>
#include <Library/DxeServicesLib.h>
#include <Protocol/FirmwareVolume2.h>
#include <Protocol/LoadedImage.h>
#include <Protocol/LoadFile2.h>
#include <Protocol/LoadFile.h>
#include <Protocol/SimpleFileSystem.h>
#include <Guid/FileInfo.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 (
             ImageHandle,
             &gEfiLoadedImageProtocolGuid,
             (VOID **) &LoadedImage
             );

  ASSERT_EFI_ERROR (Status);

  //
  // The LoadedImage->DeviceHandle may be NULL.
  // For example for DxeCore, there is LoadedImage protocol installed for it, but the
  // LoadedImage->DeviceHandle could not be initialized before the FV2 (contain DxeCore)
  // protocol is installed.
  //
  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 SectionInstance.

  The details of this search order is defined in description of EFI_FIRMWARE_VOLUME2_PROTOCOL.ReadSection ()
  found in PI Specification.

  If SectionType is EFI_SECTION_TE, EFI_SECTION_TE is used as section type to start the search. If EFI_SECTION_TE section
  is not found, EFI_SECTION_PE32 will be used to try the search again. If no EFI_SECTION_PE32 section is found, 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 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  SectionInstance         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_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
InternalGetSectionFromFv (
  IN  EFI_HANDLE                    FvHandle,
  IN  CONST EFI_GUID                *NameGuid,
  IN  EFI_SECTION_TYPE              SectionType,
  IN  UINTN                         SectionInstance,
  OUT VOID                          **Buffer,
  OUT UINTN                         *Size
  )
{
  EFI_STATUS                    Status;
  EFI_FIRMWARE_VOLUME2_PROTOCOL *Fv;
  UINT32                        AuthenticationStatus;

  ASSERT (NameGuid != NULL);
  ASSERT (Buffer != NULL);
  ASSERT (Size != NULL);

  if (FvHandle == NULL) {
    //
    // Return EFI_NOT_FOUND directly for NULL FvHandle.
    //
    return EFI_NOT_FOUND;
  }

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

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

  return Status;
}

/**
  Searches all the available firmware volumes and returns the first matching FFS section.

  This function searches all the firmware volumes for FFS files with FV file type specified by FileType
  The order that the firmware volumes is searched is not deterministic. For each available FV a search
  is made for FFS file of type FileType. If the FV contains more than one FFS file with the same FileType,
  the FileInstance instance will be the matched FFS file. For each FFS file found a search
  is made for FFS sections of type SectionType. If the FFS file contains at least SectionInstance instances
  of the FFS section specified by SectionType, then the SectionInstance instance is returned in Buffer.
  Buffer is allocated using AllocatePool(), and the size of the allocated buffer is returned in Size.
  It is the caller's responsibility to use FreePool() to free the allocated buffer.
  See EFI_FIRMWARE_VOLUME2_PROTOCOL.ReadSection() for details on how sections
  are retrieved from an FFS file based on SectionType and SectionInstance.

  If SectionType is EFI_SECTION_TE, and the search with an FFS file fails,
  the search will be retried with a section type of EFI_SECTION_PE32.
  This function must be called with a TPL <= TPL_NOTIFY.

  If Buffer is NULL, then ASSERT().
  If Size is NULL, then ASSERT().

  @param  FileType             Indicates the FV file type to search for within all
                               available FVs.
  @param  FileInstance         Indicates which file instance within all available
                               FVs specified by FileType.
                               FileInstance starts from zero.
  @param  SectionType          Indicates the FFS section type to search for
                               within the FFS file
                               specified by FileType with FileInstance.
  @param  SectionInstance      Indicates which section instance within the FFS file
                               specified by FileType with FileInstance to retrieve.
                               SectionInstance starts from zero.
  @param  Buffer               On output, a pointer to a callee allocated buffer
                               containing the FFS file section that was found.
                               Is it the caller's responsibility to free this
                               buffer using FreePool().
  @param  Size                 On output, a pointer to the size, in bytes, of Buffer.

  @retval  EFI_SUCCESS          The specified FFS section was returned.
  @retval  EFI_NOT_FOUND        The specified FFS section could not be found.
  @retval  EFI_OUT_OF_RESOURCES There are not enough resources available to retrieve
                                the matching FFS section.
  @retval  EFI_DEVICE_ERROR     The FFS section could not be retrieves due to a
                                device error.
  @retval  EFI_ACCESS_DENIED    The FFS section could not be retrieves because
                                the firmware volume that
                                contains the matching FFS section does not allow reads.
**/
EFI_STATUS
EFIAPI
GetSectionFromAnyFvByFileType  (
  IN  EFI_FV_FILETYPE               FileType,
  IN  UINTN                         FileInstance,
  IN  EFI_SECTION_TYPE              SectionType,
  IN  UINTN                         SectionInstance,
  OUT VOID                          **Buffer,
  OUT UINTN                         *Size
  )
{
  EFI_STATUS                    Status;
  EFI_HANDLE                    *HandleBuffer;
  UINTN                         HandleCount;
  UINTN                         IndexFv;
  UINTN                         IndexFile;
  UINTN                         Key;
  EFI_GUID                      NameGuid;
  EFI_FV_FILE_ATTRIBUTES        Attributes;
  EFI_FIRMWARE_VOLUME2_PROTOCOL *Fv;

  ASSERT (Buffer != NULL);
  ASSERT (Size != NULL);

  //
  // Locate all available FVs.
  //
  HandleBuffer = NULL;
  Status = gBS->LocateHandleBuffer (
                  ByProtocol,
                  &gEfiFirmwareVolume2ProtocolGuid,
                  NULL,
                  &HandleCount,
                  &HandleBuffer
                  );
  if (EFI_ERROR (Status)) {
    return Status;
  }

  //
  // Go through FVs one by one to find the required section data.
  //
  for (IndexFv = 0; IndexFv < HandleCount; IndexFv++) {
    Status = gBS->HandleProtocol (
                    HandleBuffer[IndexFv],
                    &gEfiFirmwareVolume2ProtocolGuid,
                    (VOID **)&Fv
                    );
    if (EFI_ERROR (Status)) {
      continue;
    }

    //
    // Use Firmware Volume 2 Protocol to search for a file of type FileType in all FVs.
    //
    IndexFile = FileInstance + 1;
    Key = 0;
    do {
      Status = Fv->GetNextFile (Fv, &Key, &FileType, &NameGuid, &Attributes, Size);
      if (EFI_ERROR (Status)) {
        break;
      }
      IndexFile --;
    } while (IndexFile > 0);

    //
    // Fv File with the required FV file type is found.
    // Search the section file in the found FV file.
    //
    if (IndexFile == 0) {
      Status = InternalGetSectionFromFv (
                 HandleBuffer[IndexFv],
                 &NameGuid,
                 SectionType,
                 SectionInstance,
                 Buffer,
                 Size
                 );

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

  //
  // The required FFS section file is not found.
  //
  if (IndexFv == HandleCount) {
    Status = EFI_NOT_FOUND;
  }

Done:
  if (HandleBuffer != NULL) {
    FreePool(HandleBuffer);
  }

  return Status;
}

/**
  Searches all the availables firmware volumes and returns the first matching FFS section.

  This function searches all the firmware volumes for FFS files with an FFS filename specified by NameGuid.
  The order that the firmware volumes is searched is not deterministic. For each FFS file found a search
  is made for FFS sections of type SectionType. If the FFS file contains at least SectionInstance instances
  of the FFS section specified by SectionType, then the SectionInstance instance is returned in Buffer.
  Buffer is allocated using AllocatePool(), and the size of the allocated buffer is returned in Size.
  It is the caller's responsibility to use FreePool() to free the allocated buffer.
  See EFI_FIRMWARE_VOLUME2_PROTOCOL.ReadSection() for details on how sections
  are retrieved from an FFS file based on SectionType and SectionInstance.

  If SectionType is EFI_SECTION_TE, and the search with an FFS file fails,
  the search will be retried with a section type of EFI_SECTION_PE32.
  This function must be called with a TPL <= TPL_NOTIFY.

  If NameGuid is NULL, then ASSERT().
  If Buffer is NULL, then ASSERT().
  If Size is NULL, then ASSERT().


  @param  NameGuid             A pointer to to the FFS filename GUID to search for
                               within any of the firmware volumes in the platform.
  @param  SectionType          Indicates the FFS section type to search for within
                               the FFS file specified by NameGuid.
  @param  SectionInstance      Indicates which section instance within the FFS file
                               specified by NameGuid to retrieve.
  @param  Buffer               On output, a pointer to a callee allocated buffer
                               containing the FFS file section that was found.
                               Is it the caller's responsibility to free this buffer
                               using FreePool().
  @param  Size                 On output, a pointer to the size, in bytes, of Buffer.

  @retval  EFI_SUCCESS          The specified FFS section was returned.
  @retval  EFI_NOT_FOUND        The specified FFS section could not be found.
  @retval  EFI_OUT_OF_RESOURCES There are not enough resources available to
                                retrieve the matching FFS section.
  @retval  EFI_DEVICE_ERROR     The FFS section could not be retrieves due to a
                                device error.
  @retval  EFI_ACCESS_DENIED    The FFS section could not be retrieves because the
                                firmware volume that
                                contains the matching FFS section does not allow reads.
**/
EFI_STATUS
EFIAPI
GetSectionFromAnyFv  (
  IN CONST  EFI_GUID           *NameGuid,
  IN        EFI_SECTION_TYPE   SectionType,
  IN        UINTN              SectionInstance,
  OUT       VOID               **Buffer,
  OUT       UINTN              *Size
  )
{
  EFI_STATUS                    Status;
  EFI_HANDLE                    *HandleBuffer;
  UINTN                         HandleCount;
  UINTN                         Index;
  EFI_HANDLE                    FvHandle;

  //
  // 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 = InternalGetSectionFromFv (
             FvHandle,
             NameGuid,
             SectionType,
             SectionInstance,
             Buffer,
             Size
             );
  if (!EFI_ERROR (Status)) {
    return EFI_SUCCESS;
  }

  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) {
      Status = InternalGetSectionFromFv (
                 HandleBuffer[Index],
                 NameGuid,
                 SectionType,
                 SectionInstance,
                 Buffer,
                 Size
                 );

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

  }

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

Done:

  if (HandleBuffer != NULL) {
    FreePool(HandleBuffer);
  }
  return Status;

}

/**
  Searches the firmware volume that the currently executing module was loaded from and returns the first matching FFS section.

  This function searches the firmware volume that the currently executing module was loaded
  from for an FFS file with an FFS filename specified by NameGuid. If the FFS file is found a search
  is made for FFS sections of type SectionType. If the FFS file contains at least SectionInstance
  instances of the FFS section specified by SectionType, then the SectionInstance instance is returned in Buffer.
  Buffer is allocated using AllocatePool(), and the size of the allocated buffer is returned in Size.
  It is the caller's responsibility to use FreePool() to free the allocated buffer.
  See EFI_FIRMWARE_VOLUME2_PROTOCOL.ReadSection() for details on how sections are retrieved from
  an FFS file based on SectionType and SectionInstance.

  If the currently executing module was not loaded from a firmware volume, then EFI_NOT_FOUND is returned.
  If SectionType is EFI_SECTION_TE, and the search with an FFS file fails,
  the search will be retried with a section type of EFI_SECTION_PE32.

  This function must be called with a TPL <= TPL_NOTIFY.
  If NameGuid is NULL, then ASSERT().
  If Buffer is NULL, then ASSERT().
  If Size is NULL, then ASSERT().

  @param  NameGuid             A pointer to to the FFS filename GUID to search for
                               within the firmware volumes that the currently
                               executing module was loaded from.
  @param  SectionType          Indicates the FFS section type to search for within
                               the FFS file specified by NameGuid.
  @param  SectionInstance      Indicates which section instance within the FFS file
                               specified by NameGuid to retrieve.
  @param  Buffer               On output, a pointer to a callee allocated buffer
                               containing the FFS file section that was found.
                               Is it the caller's responsibility to free this buffer
                               using FreePool().
  @param  Size                 On output, a pointer to the size, in bytes, of Buffer.


  @retval  EFI_SUCCESS          The specified FFS section was returned.
  @retval  EFI_NOT_FOUND        The specified FFS section could not be found.
  @retval  EFI_OUT_OF_RESOURCES There are not enough resources available to retrieve
                                the matching FFS section.
  @retval  EFI_DEVICE_ERROR     The FFS section could not be retrieves due to a
                                device error.
  @retval  EFI_ACCESS_DENIED    The FFS section could not be retrieves because the
                                firmware volume that contains the matching FFS
                                section does not allow reads.
**/
EFI_STATUS
EFIAPI
GetSectionFromFv (
  IN  CONST EFI_GUID                *NameGuid,
  IN  EFI_SECTION_TYPE              SectionType,
  IN  UINTN                         SectionInstance,
  OUT VOID                          **Buffer,
  OUT UINTN                         *Size
    )
{
  return InternalGetSectionFromFv (
           InternalImageHandleToFvHandle(gImageHandle),
           NameGuid,
           SectionType,
           SectionInstance,
           Buffer,
           Size
           );
}


/**
  Searches the FFS file the the currently executing module was loaded from and returns the first matching FFS section.

  This function searches the FFS file that the currently executing module was loaded from for a FFS sections of type SectionType.
  If the FFS file contains at least SectionInstance instances of the FFS section specified by SectionType,
  then the SectionInstance instance is returned in Buffer. Buffer is allocated using AllocatePool(),
  and the size of the allocated buffer is returned in Size. It is the caller's responsibility
  to use FreePool() to free the allocated buffer. See EFI_FIRMWARE_VOLUME2_PROTOCOL.ReadSection() for
  details on how sections are retrieved from an FFS file based on SectionType and SectionInstance.

  If the currently executing module was not loaded from an FFS file, then EFI_NOT_FOUND is returned.
  If SectionType is EFI_SECTION_TE, and the search with an FFS file fails,
  the search will be retried with a section type of EFI_SECTION_PE32.
  This function must be called with a TPL <= TPL_NOTIFY.

  If Buffer is NULL, then ASSERT().
  If Size is NULL, then ASSERT().


  @param  SectionType          Indicates the FFS section type to search for within
                               the FFS file that the currently executing module
                               was loaded from.
  @param  SectionInstance      Indicates which section instance to retrieve within
                               the FFS file that the currently executing module
                               was loaded from.
  @param  Buffer               On output, a pointer to a callee allocated buffer
                               containing the FFS file section that was found.
                               Is it the caller's responsibility to free this buffer
                               using FreePool().
  @param  Size                 On output, a pointer to the size, in bytes, of Buffer.

  @retval  EFI_SUCCESS          The specified FFS section was returned.
  @retval  EFI_NOT_FOUND        The specified FFS section could not be found.
  @retval  EFI_OUT_OF_RESOURCES There are not enough resources available to retrieve
                                the matching FFS section.
  @retval  EFI_DEVICE_ERROR     The FFS section could not be retrieves due to a
                                device error.
  @retval  EFI_ACCESS_DENIED    The FFS section could not be retrieves because the
                                firmware volume that contains the matching FFS
                                section does not allow reads.

**/
EFI_STATUS
EFIAPI
GetSectionFromFfs (
  IN  EFI_SECTION_TYPE              SectionType,
  IN  UINTN                         SectionInstance,
  OUT VOID                          **Buffer,
  OUT UINTN                         *Size
    )
{
  return InternalGetSectionFromFv(
           InternalImageHandleToFvHandle(gImageHandle),
           &gEfiCallerIdGuid,
           SectionType,
           SectionInstance,
           Buffer,
           Size
           );
}


/**
  Get the image file buffer data and buffer size by its device path.

  Access the file either from a firmware volume, from a file system interface,
  or from the load file interface.

  Allocate memory to store the found image. The caller is responsible to free memory.

  If FilePath is NULL, then NULL is returned.
  If FileSize is NULL, then NULL is returned.
  If AuthenticationStatus is NULL, then NULL is returned.

  @param[in]       BootPolicy           Policy for Open Image File.If TRUE, indicates
                                        that the request originates from the boot
                                        manager, and that the boot manager is
                                        attempting to load FilePath as a boot
                                        selection. If FALSE, then FilePath must
                                        match an exact file to be loaded.
  @param[in]       FilePath             The pointer to the device path of the file
                                        that is absracted to the file buffer.
  @param[out]      FileSize             The pointer to the size of the abstracted
                                        file buffer.
  @param[out]      AuthenticationStatus Pointer to the authentication status.

  @retval NULL   FilePath is NULL, or FileSize is NULL, or AuthenticationStatus is NULL, or the file can't be found.
  @retval other  The abstracted file buffer. The caller is responsible to free memory.
**/
VOID *
EFIAPI
GetFileBufferByFilePath (
  IN BOOLEAN                           BootPolicy,
  IN CONST EFI_DEVICE_PATH_PROTOCOL    *FilePath,
  OUT      UINTN                       *FileSize,
  OUT UINT32                           *AuthenticationStatus
  )
{
  EFI_DEVICE_PATH_PROTOCOL          *DevicePathNode;
  EFI_DEVICE_PATH_PROTOCOL          *OrigDevicePathNode;
  EFI_DEVICE_PATH_PROTOCOL          *TempDevicePathNode;
  EFI_HANDLE                        Handle;
  EFI_GUID                          *FvNameGuid;
  EFI_FIRMWARE_VOLUME2_PROTOCOL     *FwVol;
  EFI_SECTION_TYPE                  SectionType;
  UINT8                             *ImageBuffer;
  UINTN                             ImageBufferSize;
  EFI_FV_FILETYPE                   Type;
  EFI_FV_FILE_ATTRIBUTES            Attrib;
  EFI_SIMPLE_FILE_SYSTEM_PROTOCOL   *Volume;
  EFI_FILE_HANDLE                   FileHandle;
  EFI_FILE_HANDLE                   LastHandle;
  EFI_FILE_INFO                     *FileInfo;
  UINTN                             FileInfoSize;
  EFI_LOAD_FILE_PROTOCOL            *LoadFile;
  EFI_LOAD_FILE2_PROTOCOL           *LoadFile2;
  EFI_STATUS                        Status;

  //
  // Check input File device path.
  //
  if (FilePath == NULL || FileSize == NULL || AuthenticationStatus == NULL) {
    return NULL;
  }

  //
  // Init local variable
  //
  TempDevicePathNode  = NULL;
  FvNameGuid          = NULL;
  FileInfo            = NULL;
  FileHandle          = NULL;
  ImageBuffer         = NULL;
  ImageBufferSize     = 0;
  *AuthenticationStatus = 0;

  //
  // Copy File Device Path
  //
  OrigDevicePathNode = DuplicateDevicePath (FilePath);
  if (OrigDevicePathNode == NULL) {
    return NULL;
  }

  //
  // Check whether this device path support FV2 protocol.
  // Is so, this device path may contain a Image.
  //
  DevicePathNode = OrigDevicePathNode;
  Status = gBS->LocateDevicePath (&gEfiFirmwareVolume2ProtocolGuid, &DevicePathNode, &Handle);
  if (!EFI_ERROR (Status)) {
    //
    // For FwVol File system there is only a single file name that is a GUID.
    //
    FvNameGuid = EfiGetNameGuidFromFwVolDevicePathNode ((CONST MEDIA_FW_VOL_FILEPATH_DEVICE_PATH *) DevicePathNode);
    if (FvNameGuid == NULL) {
      Status = EFI_INVALID_PARAMETER;
    } else {
      //
      // Read image from the firmware file
      //
      Status = gBS->HandleProtocol (Handle, &gEfiFirmwareVolume2ProtocolGuid, (VOID**)&FwVol);
      if (!EFI_ERROR (Status)) {
        SectionType = EFI_SECTION_PE32;
        ImageBuffer = NULL;
        Status = FwVol->ReadSection (
                          FwVol,
                          FvNameGuid,
                          SectionType,
                          0,
                          (VOID **)&ImageBuffer,
                          &ImageBufferSize,
                          AuthenticationStatus
                          );
        if (EFI_ERROR (Status)) {
          //
          // Try a raw file, since a PE32 SECTION does not exist
          //
          if (ImageBuffer != NULL) {
            FreePool (ImageBuffer);
            *AuthenticationStatus = 0;
          }
          ImageBuffer = NULL;
          Status = FwVol->ReadFile (
                            FwVol,
                            FvNameGuid,
                            (VOID **)&ImageBuffer,
                            &ImageBufferSize,
                            &Type,
                            &Attrib,
                            AuthenticationStatus
                            );
        }
      }
    }
    if (!EFI_ERROR (Status)) {
      goto Finish;
    }
  }

  //
  // Attempt to access the file via a file system interface
  //
  DevicePathNode = OrigDevicePathNode;
  Status = gBS->LocateDevicePath (&gEfiSimpleFileSystemProtocolGuid, &DevicePathNode, &Handle);
  if (!EFI_ERROR (Status)) {
    Status = gBS->HandleProtocol (Handle, &gEfiSimpleFileSystemProtocolGuid, (VOID**)&Volume);
    if (!EFI_ERROR (Status)) {
      //
      // Open the Volume to get the File System handle
      //
      Status = Volume->OpenVolume (Volume, &FileHandle);
      if (!EFI_ERROR (Status)) {
        //
        // Duplicate the device path to avoid the access to unaligned device path node.
        // Because the device path consists of one or more FILE PATH MEDIA DEVICE PATH
        // nodes, It assures the fields in device path nodes are 2 byte aligned.
        //
        TempDevicePathNode = DuplicateDevicePath (DevicePathNode);
        if (TempDevicePathNode == NULL) {
          FileHandle->Close (FileHandle);
          //
          // Setting Status to an EFI_ERROR value will cause the rest of
          // the file system support below to be skipped.
          //
          Status = EFI_OUT_OF_RESOURCES;
        }
        //
        // Parse each MEDIA_FILEPATH_DP node. There may be more than one, since the
        // directory information and filename can be seperate. The goal is to inch
        // our way down each device path node and close the previous node
        //
        DevicePathNode = TempDevicePathNode;
        while (!EFI_ERROR (Status) && !IsDevicePathEnd (DevicePathNode)) {
          if (DevicePathType (DevicePathNode) != MEDIA_DEVICE_PATH ||
              DevicePathSubType (DevicePathNode) != MEDIA_FILEPATH_DP) {
            Status = EFI_UNSUPPORTED;
            break;
          }

          LastHandle = FileHandle;
          FileHandle = NULL;

          Status = LastHandle->Open (
                                LastHandle,
                                &FileHandle,
                                ((FILEPATH_DEVICE_PATH *) DevicePathNode)->PathName,
                                EFI_FILE_MODE_READ,
                                0
                                );

          //
          // Close the previous node
          //
          LastHandle->Close (LastHandle);

          DevicePathNode = NextDevicePathNode (DevicePathNode);
        }

        if (!EFI_ERROR (Status)) {
          //
          // We have found the file. Now we need to read it. Before we can read the file we need to
          // figure out how big the file is.
          //
          FileInfo = NULL;
          FileInfoSize = 0;
          Status = FileHandle->GetInfo (
                                FileHandle,
                                &gEfiFileInfoGuid,
                                &FileInfoSize,
                                FileInfo
                                );

          if (Status == EFI_BUFFER_TOO_SMALL) {
            FileInfo = AllocatePool (FileInfoSize);
            if (FileInfo == NULL) {
              Status = EFI_OUT_OF_RESOURCES;
            } else {
              Status = FileHandle->GetInfo (
                                    FileHandle,
                                    &gEfiFileInfoGuid,
                                    &FileInfoSize,
                                    FileInfo
                                    );
            }
          }

          if (!EFI_ERROR (Status) && (FileInfo != NULL)) {
            if ((FileInfo->Attribute & EFI_FILE_DIRECTORY) == 0) {
              //
              // Allocate space for the file
              //
              ImageBuffer = AllocatePool ((UINTN)FileInfo->FileSize);
              if (ImageBuffer == NULL) {
                Status = EFI_OUT_OF_RESOURCES;
              } else {
                //
                // Read the file into the buffer we allocated
                //
                ImageBufferSize = (UINTN)FileInfo->FileSize;
                Status          = FileHandle->Read (FileHandle, &ImageBufferSize, ImageBuffer);
              }
            }
          }
        }
        //
        // Close the file and Free FileInfo and TempDevicePathNode since we are done
        //
        if (FileInfo != NULL) {
          FreePool (FileInfo);
        }
        if (FileHandle != NULL) {
          FileHandle->Close (FileHandle);
        }
        if (TempDevicePathNode != NULL) {
          FreePool (TempDevicePathNode);
        }
      }
    }
    if (!EFI_ERROR (Status)) {
      goto Finish;
    }
  }

  //
  // Attempt to access the file via LoadFile2 interface
  //
  if (!BootPolicy) {
    DevicePathNode = OrigDevicePathNode;
    Status = gBS->LocateDevicePath (&gEfiLoadFile2ProtocolGuid, &DevicePathNode, &Handle);
    if (!EFI_ERROR (Status)) {
      Status = gBS->HandleProtocol (Handle, &gEfiLoadFile2ProtocolGuid, (VOID**)&LoadFile2);
      if (!EFI_ERROR (Status)) {
        //
        // Call LoadFile2 with the correct buffer size
        //
        ImageBufferSize = 0;
        ImageBuffer     = NULL;
        Status = LoadFile2->LoadFile (
                             LoadFile2,
                             DevicePathNode,
                             FALSE,
                             &ImageBufferSize,
                             ImageBuffer
                             );
        if (Status == EFI_BUFFER_TOO_SMALL) {
          ImageBuffer = AllocatePool (ImageBufferSize);
          if (ImageBuffer == NULL) {
            Status = EFI_OUT_OF_RESOURCES;
          } else {
            Status = LoadFile2->LoadFile (
                                 LoadFile2,
                                 DevicePathNode,
                                 FALSE,
                                 &ImageBufferSize,
                                 ImageBuffer
                                 );
          }
        }
      }
      if (!EFI_ERROR (Status)) {
        goto Finish;
      }
    }
  }

  //
  // Attempt to access the file via LoadFile interface
  //
  DevicePathNode = OrigDevicePathNode;
  Status = gBS->LocateDevicePath (&gEfiLoadFileProtocolGuid, &DevicePathNode, &Handle);
  if (!EFI_ERROR (Status)) {
    Status = gBS->HandleProtocol (Handle, &gEfiLoadFileProtocolGuid, (VOID**)&LoadFile);
    if (!EFI_ERROR (Status)) {
      //
      // Call LoadFile with the correct buffer size
      //
      ImageBufferSize = 0;
      ImageBuffer     = NULL;
      Status = LoadFile->LoadFile (
                           LoadFile,
                           DevicePathNode,
                           BootPolicy,
                           &ImageBufferSize,
                           ImageBuffer
                           );
      if (Status == EFI_BUFFER_TOO_SMALL) {
        ImageBuffer = AllocatePool (ImageBufferSize);
        if (ImageBuffer == NULL) {
          Status = EFI_OUT_OF_RESOURCES;
        } else {
          Status = LoadFile->LoadFile (
                               LoadFile,
                               DevicePathNode,
                               BootPolicy,
                               &ImageBufferSize,
                               ImageBuffer
                               );
        }
      }
    }
  }

Finish:

  if (EFI_ERROR (Status)) {
    if (ImageBuffer != NULL) {
      FreePool (ImageBuffer);
      ImageBuffer = NULL;
    }
    *FileSize = 0;
  } else {
    *FileSize = ImageBufferSize;
  }

  FreePool (OrigDevicePathNode);

  return ImageBuffer;
}

/**
  Searches all the available firmware volumes and returns the file device path of first matching
  FFS section.

  This function searches all the firmware volumes for FFS files with an FFS filename specified by NameGuid.
  The order that the firmware volumes is searched is not deterministic. For each FFS file found a search
  is made for FFS sections of type SectionType.

  If SectionType is EFI_SECTION_TE, and the search with an FFS file fails,
  the search will be retried with a section type of EFI_SECTION_PE32.
  This function must be called with a TPL <= TPL_NOTIFY.

  If NameGuid is NULL, then ASSERT().

   @param  NameGuid             A pointer to to the FFS filename GUID to search for
                                within any of the firmware volumes in the platform.
   @param  SectionType          Indicates the FFS section type to search for within
                                the FFS file specified by NameGuid.
   @param  SectionInstance      Indicates which section instance within the FFS file
                                specified by NameGuid to retrieve.
   @param  FvFileDevicePath     Device path for the target FFS
                                file.

   @retval  EFI_SUCCESS           The specified file device path of FFS section was returned.
   @retval  EFI_NOT_FOUND         The specified file device path of FFS section could not be found.
   @retval  EFI_DEVICE_ERROR      The FFS section could not be retrieves due to a
                                  device error.
   @retval  EFI_ACCESS_DENIED     The FFS section could not be retrieves because the
                                  firmware volume that contains the matching FFS section does not
                                  allow reads.
   @retval  EFI_INVALID_PARAMETER FvFileDevicePath is NULL.

**/
EFI_STATUS
EFIAPI
GetFileDevicePathFromAnyFv (
  IN CONST  EFI_GUID                  *NameGuid,
  IN        EFI_SECTION_TYPE          SectionType,
  IN        UINTN                     SectionInstance,
  OUT       EFI_DEVICE_PATH_PROTOCOL  **FvFileDevicePath
  )
{
  EFI_STATUS                        Status;
  EFI_HANDLE                        *HandleBuffer;
  UINTN                             HandleCount;
  UINTN                             Index;
  EFI_HANDLE                        FvHandle;
  EFI_DEVICE_PATH_PROTOCOL          *FvDevicePath;
  MEDIA_FW_VOL_FILEPATH_DEVICE_PATH *TempFvFileDevicePath;
  VOID                              *Buffer;
  UINTN                             Size;

  if (FvFileDevicePath == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  HandleBuffer         = NULL;
  FvDevicePath         = NULL;
  TempFvFileDevicePath = NULL;
  Buffer               = NULL;
  Size                 = 0;

  //
  // 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 = InternalGetSectionFromFv (
             FvHandle,
             NameGuid,
             SectionType,
             SectionInstance,
             &Buffer,
             &Size
             );
  if (!EFI_ERROR (Status)) {
    goto Done;
  }

  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) {
      Status = InternalGetSectionFromFv (
                 HandleBuffer[Index],
                 NameGuid,
                 SectionType,
                 SectionInstance,
                 &Buffer,
                 &Size
                 );

      if (!EFI_ERROR (Status)) {
        //
        // Update FvHandle to the current handle.
        //
        FvHandle = HandleBuffer[Index];
        goto Done;
      }
    }
  }

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

Done:
  if (Status == EFI_SUCCESS) {
    //
    // Build a device path to the file in the FV to pass into gBS->LoadImage
    //
    Status = gBS->HandleProtocol (FvHandle, &gEfiDevicePathProtocolGuid, (VOID **)&FvDevicePath);
    if (EFI_ERROR (Status)) {
      *FvFileDevicePath = NULL;
    } else {
      TempFvFileDevicePath = AllocateZeroPool (sizeof (MEDIA_FW_VOL_FILEPATH_DEVICE_PATH) + END_DEVICE_PATH_LENGTH);
      if (TempFvFileDevicePath == NULL) {
        *FvFileDevicePath = NULL;
        return EFI_OUT_OF_RESOURCES;
      }
      EfiInitializeFwVolDevicepathNode ((MEDIA_FW_VOL_FILEPATH_DEVICE_PATH*)TempFvFileDevicePath, NameGuid);
      SetDevicePathEndNode (NextDevicePathNode (TempFvFileDevicePath));
      *FvFileDevicePath = AppendDevicePath (
                            FvDevicePath,
                            (EFI_DEVICE_PATH_PROTOCOL *)TempFvFileDevicePath
                            );
      FreePool (TempFvFileDevicePath);
    }
  }

  if (Buffer != NULL) {
    FreePool (Buffer);
  }

  if (HandleBuffer != NULL) {
    FreePool (HandleBuffer);
  }

  return Status;
}