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
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
|
/** @file
SMM Driver Dispatcher.
Step #1 - When a FV protocol is added to the system every driver in the FV
is added to the mDiscoveredList. The Before, and After Depex are
pre-processed as drivers are added to the mDiscoveredList. If an Apriori
file exists in the FV those drivers are addeded to the
mScheduledQueue. The mFvHandleList is used to make sure a
FV is only processed once.
Step #2 - Dispatch. Remove driver from the mScheduledQueue and load and
start it. After mScheduledQueue is drained check the
mDiscoveredList to see if any item has a Depex that is ready to
be placed on the mScheduledQueue.
Step #3 - Adding to the mScheduledQueue requires that you process Before
and After dependencies. This is done recursively as the call to add
to the mScheduledQueue checks for Before and recursively adds
all Befores. It then addes the item that was passed in and then
processess the After dependecies by recursively calling the routine.
Dispatcher Rules:
The rules for the dispatcher are similar to the DXE dispatcher.
The rules for DXE dispatcher are in chapter 10 of the DXE CIS. Figure 10-3
is the state diagram for the DXE dispatcher
Depex - Dependency Expresion.
Copyright (c) 2009 - 2011, Intel Corporation. All rights reserved.<BR>
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 "PiSmmCore.h"
//
// SMM Dispatcher Data structures
//
#define KNOWN_HANDLE_SIGNATURE SIGNATURE_32('k','n','o','w')
typedef struct {
UINTN Signature;
LIST_ENTRY Link; // mFvHandleList
EFI_HANDLE Handle;
} KNOWN_HANDLE;
//
// Function Prototypes
//
/**
Insert InsertedDriverEntry onto the mScheduledQueue. To do this you
must add any driver with a before dependency on InsertedDriverEntry first.
You do this by recursively calling this routine. After all the Befores are
processed you can add InsertedDriverEntry to the mScheduledQueue.
Then you can add any driver with an After dependency on InsertedDriverEntry
by recursively calling this routine.
@param InsertedDriverEntry The driver to insert on the ScheduledLink Queue
**/
VOID
SmmInsertOnScheduledQueueWhileProcessingBeforeAndAfter (
IN EFI_SMM_DRIVER_ENTRY *InsertedDriverEntry
);
//
// The Driver List contains one copy of every driver that has been discovered.
// Items are never removed from the driver list. List of EFI_SMM_DRIVER_ENTRY
//
LIST_ENTRY mDiscoveredList = INITIALIZE_LIST_HEAD_VARIABLE (mDiscoveredList);
//
// Queue of drivers that are ready to dispatch. This queue is a subset of the
// mDiscoveredList.list of EFI_SMM_DRIVER_ENTRY.
//
LIST_ENTRY mScheduledQueue = INITIALIZE_LIST_HEAD_VARIABLE (mScheduledQueue);
//
// List of handles who's Fv's have been parsed and added to the mFwDriverList.
//
LIST_ENTRY mFvHandleList = INITIALIZE_LIST_HEAD_VARIABLE (mFvHandleList);
//
// Flag for the SMM Dispacher. TRUE if dispatcher is execuing.
//
BOOLEAN gDispatcherRunning = FALSE;
//
// Flag for the SMM Dispacher. TRUE if there is one or more SMM drivers ready to be dispatched
//
BOOLEAN gRequestDispatch = FALSE;
//
// List of file types supported by dispatcher
//
EFI_FV_FILETYPE mSmmFileTypes[] = {
EFI_FV_FILETYPE_SMM,
EFI_FV_FILETYPE_COMBINED_SMM_DXE
//
// Note: DXE core will process the FV image file, so skip it in SMM core
// EFI_FV_FILETYPE_FIRMWARE_VOLUME_IMAGE
//
};
typedef struct {
MEDIA_FW_VOL_FILEPATH_DEVICE_PATH File;
EFI_DEVICE_PATH_PROTOCOL End;
} FV_FILEPATH_DEVICE_PATH;
FV_FILEPATH_DEVICE_PATH mFvDevicePath;
//
// DXE Architecture Protocols
//
EFI_SECURITY_ARCH_PROTOCOL *mSecurity = NULL;
//
// The global variable is defined for Loading modules at fixed address feature to track the SMM code
// memory range usage. It is a bit mapped array in which every bit indicates the correspoding
// memory page available or not.
//
GLOBAL_REMOVE_IF_UNREFERENCED UINT64 *mSmmCodeMemoryRangeUsageBitMap=NULL;
/**
To check memory usage bit map array to figure out if the memory range in which the image will be loaded is available or not. If
memory range is avaliable, the function will mark the correponding bits to 1 which indicates the memory range is used.
The function is only invoked when load modules at fixed address feature is enabled.
@param ImageBase The base addres the image will be loaded at.
@param ImageSize The size of the image
@retval EFI_SUCCESS The memory range the image will be loaded in is available
@retval EFI_NOT_FOUND The memory range the image will be loaded in is not available
**/
EFI_STATUS
CheckAndMarkFixLoadingMemoryUsageBitMap (
IN EFI_PHYSICAL_ADDRESS ImageBase,
IN UINTN ImageSize
)
{
UINT32 SmmCodePageNumber;
UINT64 SmmCodeSize;
EFI_PHYSICAL_ADDRESS SmmCodeBase;
UINTN BaseOffsetPageNumber;
UINTN TopOffsetPageNumber;
UINTN Index;
//
// Build tool will calculate the smm code size and then patch the PcdLoadFixAddressSmmCodePageNumber
//
SmmCodePageNumber = PcdGet32(PcdLoadFixAddressSmmCodePageNumber);
SmmCodeSize = EFI_PAGES_TO_SIZE (SmmCodePageNumber);
SmmCodeBase = gLoadModuleAtFixAddressSmramBase;
//
// If the memory usage bit map is not initialized, do it. Every bit in the array
// indicate the status of the corresponding memory page, available or not
//
if (mSmmCodeMemoryRangeUsageBitMap == NULL) {
mSmmCodeMemoryRangeUsageBitMap = AllocateZeroPool(((SmmCodePageNumber / 64) + 1)*sizeof(UINT64));
}
//
// If the Dxe code memory range is not allocated or the bit map array allocation failed, return EFI_NOT_FOUND
//
if (mSmmCodeMemoryRangeUsageBitMap == NULL) {
return EFI_NOT_FOUND;
}
//
// see if the memory range for loading the image is in the SMM code range.
//
if (SmmCodeBase + SmmCodeSize < ImageBase + ImageSize || SmmCodeBase > ImageBase) {
return EFI_NOT_FOUND;
}
//
// Test if the memory is avalaible or not.
//
BaseOffsetPageNumber = (UINTN)EFI_SIZE_TO_PAGES((UINT32)(ImageBase - SmmCodeBase));
TopOffsetPageNumber = (UINTN)EFI_SIZE_TO_PAGES((UINT32)(ImageBase + ImageSize - SmmCodeBase));
for (Index = BaseOffsetPageNumber; Index < TopOffsetPageNumber; Index ++) {
if ((mSmmCodeMemoryRangeUsageBitMap[Index / 64] & LShiftU64(1, (Index % 64))) != 0) {
//
// This page is already used.
//
return EFI_NOT_FOUND;
}
}
//
// Being here means the memory range is available. So mark the bits for the memory range
//
for (Index = BaseOffsetPageNumber; Index < TopOffsetPageNumber; Index ++) {
mSmmCodeMemoryRangeUsageBitMap[Index / 64] |= LShiftU64(1, (Index % 64));
}
return EFI_SUCCESS;
}
/**
Get the fixed loadding address from image header assigned by build tool. This function only be called
when Loading module at Fixed address feature enabled.
@param ImageContext Pointer to the image context structure that describes the PE/COFF
image that needs to be examined by this function.
@retval EFI_SUCCESS An fixed loading address is assigned to this image by build tools .
@retval EFI_NOT_FOUND The image has no assigned fixed loadding address.
**/
EFI_STATUS
GetPeCoffImageFixLoadingAssignedAddress(
IN OUT PE_COFF_LOADER_IMAGE_CONTEXT *ImageContext
)
{
UINTN SectionHeaderOffset;
EFI_STATUS Status;
EFI_IMAGE_SECTION_HEADER SectionHeader;
EFI_IMAGE_OPTIONAL_HEADER_UNION *ImgHdr;
EFI_PHYSICAL_ADDRESS FixLoaddingAddress;
UINT16 Index;
UINTN Size;
UINT16 NumberOfSections;
UINT64 ValueInSectionHeader;
FixLoaddingAddress = 0;
Status = EFI_NOT_FOUND;
//
// Get PeHeader pointer
//
ImgHdr = (EFI_IMAGE_OPTIONAL_HEADER_UNION *)((CHAR8* )ImageContext->Handle + ImageContext->PeCoffHeaderOffset);
SectionHeaderOffset = (UINTN)(
ImageContext->PeCoffHeaderOffset +
sizeof (UINT32) +
sizeof (EFI_IMAGE_FILE_HEADER) +
ImgHdr->Pe32.FileHeader.SizeOfOptionalHeader
);
NumberOfSections = ImgHdr->Pe32.FileHeader.NumberOfSections;
//
// Get base address from the first section header that doesn't point to code section.
//
for (Index = 0; Index < NumberOfSections; Index++) {
//
// Read section header from file
//
Size = sizeof (EFI_IMAGE_SECTION_HEADER);
Status = ImageContext->ImageRead (
ImageContext->Handle,
SectionHeaderOffset,
&Size,
&SectionHeader
);
if (EFI_ERROR (Status)) {
return Status;
}
Status = EFI_NOT_FOUND;
if ((SectionHeader.Characteristics & EFI_IMAGE_SCN_CNT_CODE) == 0) {
//
// Build tool will save the address in PointerToRelocations & PointerToLineNumbers fields in the first section header
// that doesn't point to code section in image header.So there is an assumption that when the feature is enabled,
// if a module with a loading address assigned by tools, the PointerToRelocations & PointerToLineNumbers fields
// should not be Zero, or else, these 2 fileds should be set to Zero
//
ValueInSectionHeader = ReadUnaligned64((UINT64*)&SectionHeader.PointerToRelocations);
if (ValueInSectionHeader != 0) {
//
// Found first section header that doesn't point to code section in which uild tool saves the
// offset to SMRAM base as image base in PointerToRelocations & PointerToLineNumbers fields
//
FixLoaddingAddress = (EFI_PHYSICAL_ADDRESS)(gLoadModuleAtFixAddressSmramBase + (INT64)ValueInSectionHeader);
//
// Check if the memory range is avaliable.
//
Status = CheckAndMarkFixLoadingMemoryUsageBitMap (FixLoaddingAddress, (UINTN)(ImageContext->ImageSize + ImageContext->SectionAlignment));
if (!EFI_ERROR(Status)) {
//
// The assigned address is valid. Return the specified loadding address
//
ImageContext->ImageAddress = FixLoaddingAddress;
}
}
break;
}
SectionHeaderOffset += sizeof (EFI_IMAGE_SECTION_HEADER);
}
DEBUG ((EFI_D_INFO|EFI_D_LOAD, "LOADING MODULE FIXED INFO: Loading module at fixed address %x, Status = %r\n", FixLoaddingAddress, Status));
return Status;
}
/**
Loads an EFI image into SMRAM.
@param DriverEntry EFI_SMM_DRIVER_ENTRY instance
@return EFI_STATUS
**/
EFI_STATUS
EFIAPI
SmmLoadImage (
IN OUT EFI_SMM_DRIVER_ENTRY *DriverEntry
)
{
UINT32 AuthenticationStatus;
UINTN FilePathSize;
VOID *Buffer;
UINTN Size;
UINTN PageCount;
EFI_GUID *NameGuid;
EFI_STATUS Status;
EFI_STATUS SecurityStatus;
EFI_HANDLE DeviceHandle;
EFI_PHYSICAL_ADDRESS DstBuffer;
EFI_DEVICE_PATH_PROTOCOL *FilePath;
EFI_DEVICE_PATH_PROTOCOL *OriginalFilePath;
EFI_DEVICE_PATH_PROTOCOL *HandleFilePath;
EFI_FIRMWARE_VOLUME2_PROTOCOL *Fv;
PE_COFF_LOADER_IMAGE_CONTEXT ImageContext;
Buffer = NULL;
Size = 0;
Fv = DriverEntry->Fv;
NameGuid = &DriverEntry->FileName;
FilePath = DriverEntry->FvFileDevicePath;
OriginalFilePath = FilePath;
HandleFilePath = FilePath;
DeviceHandle = NULL;
SecurityStatus = EFI_SUCCESS;
Status = EFI_SUCCESS;
AuthenticationStatus = 0;
//
// Try to get the image device handle by checking the match protocol.
//
Status = gBS->LocateDevicePath (&gEfiFirmwareVolume2ProtocolGuid, &HandleFilePath, &DeviceHandle);
if (EFI_ERROR(Status)) {
return Status;
}
//
// If the Security Architectural Protocol has not been located yet, then attempt to locate it
//
if (mSecurity == NULL) {
gBS->LocateProtocol (&gEfiSecurityArchProtocolGuid, NULL, (VOID**)&mSecurity);
}
//
// Verify the Authentication Status through the Security Architectural Protocol
//
if ((mSecurity != NULL) && (OriginalFilePath != NULL)) {
SecurityStatus = mSecurity->FileAuthenticationState (
mSecurity,
AuthenticationStatus,
OriginalFilePath
);
if (EFI_ERROR (SecurityStatus) && SecurityStatus != EFI_SECURITY_VIOLATION) {
Status = SecurityStatus;
return Status;
}
}
//
// Pull out just the file portion of the DevicePath for the LoadedImage FilePath
//
FilePath = OriginalFilePath;
Status = gBS->HandleProtocol (DeviceHandle, &gEfiDevicePathProtocolGuid, (VOID **)&HandleFilePath);
if (!EFI_ERROR (Status)) {
FilePathSize = GetDevicePathSize (HandleFilePath) - sizeof(EFI_DEVICE_PATH_PROTOCOL);
FilePath = (EFI_DEVICE_PATH_PROTOCOL *) (((UINT8 *)FilePath) + FilePathSize );
}
//
// Try reading PE32 section firstly
//
Status = Fv->ReadSection (
Fv,
NameGuid,
EFI_SECTION_PE32,
0,
&Buffer,
&Size,
&AuthenticationStatus
);
if (EFI_ERROR (Status)) {
//
// Try reading TE section secondly
//
Buffer = NULL;
Size = 0;
Status = Fv->ReadSection (
Fv,
NameGuid,
EFI_SECTION_TE,
0,
&Buffer,
&Size,
&AuthenticationStatus
);
}
if (EFI_ERROR (Status)) {
if (Buffer != NULL) {
Status = gBS->FreePool (Buffer);
}
return Status;
}
//
// Initialize ImageContext
//
ImageContext.Handle = Buffer;
ImageContext.ImageRead = PeCoffLoaderImageReadFromMemory;
//
// Get information about the image being loaded
//
Status = PeCoffLoaderGetImageInfo (&ImageContext);
if (EFI_ERROR (Status)) {
if (Buffer != NULL) {
Status = gBS->FreePool (Buffer);
}
return Status;
}
//
// if Loading module at Fixed Address feature is enabled, then cut out a memory range started from TESG BASE
// to hold the Smm driver code
//
if (PcdGet64(PcdLoadModuleAtFixAddressEnable) != 0) {
//
// Get the fixed loading address assigned by Build tool
//
Status = GetPeCoffImageFixLoadingAssignedAddress (&ImageContext);
if (!EFI_ERROR (Status)) {
//
// Since the memory range to load Smm core alreay been cut out, so no need to allocate and free this range
// following statements is to bypass SmmFreePages
//
PageCount = 0;
DstBuffer = (UINTN)gLoadModuleAtFixAddressSmramBase;
} else {
DEBUG ((EFI_D_INFO|EFI_D_LOAD, "LOADING MODULE FIXED ERROR: Failed to load module at fixed address. \n"));
//
// allocate the memory to load the SMM driver
//
PageCount = (UINTN)EFI_SIZE_TO_PAGES(ImageContext.ImageSize + ImageContext.SectionAlignment);
DstBuffer = (UINTN)(-1);
Status = SmmAllocatePages (
AllocateMaxAddress,
EfiRuntimeServicesCode,
PageCount,
&DstBuffer
);
if (EFI_ERROR (Status)) {
if (Buffer != NULL) {
Status = gBS->FreePool (Buffer);
}
return Status;
}
ImageContext.ImageAddress = (EFI_PHYSICAL_ADDRESS)DstBuffer;
}
} else {
PageCount = (UINTN)EFI_SIZE_TO_PAGES(ImageContext.ImageSize + ImageContext.SectionAlignment);
DstBuffer = (UINTN)(-1);
Status = SmmAllocatePages (
AllocateMaxAddress,
EfiRuntimeServicesCode,
PageCount,
&DstBuffer
);
if (EFI_ERROR (Status)) {
if (Buffer != NULL) {
Status = gBS->FreePool (Buffer);
}
return Status;
}
ImageContext.ImageAddress = (EFI_PHYSICAL_ADDRESS)DstBuffer;
}
//
// Align buffer on section boundry
//
ImageContext.ImageAddress += ImageContext.SectionAlignment - 1;
ImageContext.ImageAddress &= ~(ImageContext.SectionAlignment - 1);
//
// Load the image to our new buffer
//
Status = PeCoffLoaderLoadImage (&ImageContext);
if (EFI_ERROR (Status)) {
if (Buffer != NULL) {
Status = gBS->FreePool (Buffer);
}
SmmFreePages (DstBuffer, PageCount);
return Status;
}
//
// Relocate the image in our new buffer
//
Status = PeCoffLoaderRelocateImage (&ImageContext);
if (EFI_ERROR (Status)) {
if (Buffer != NULL) {
Status = gBS->FreePool (Buffer);
}
SmmFreePages (DstBuffer, PageCount);
return Status;
}
//
// Flush the instruction cache so the image data are written before we execute it
//
InvalidateInstructionCacheRange ((VOID *)(UINTN) ImageContext.ImageAddress, (UINTN) ImageContext.ImageSize);
//
// Save Image EntryPoint in DriverEntry
//
DriverEntry->ImageEntryPoint = ImageContext.EntryPoint;
DriverEntry->ImageBuffer = DstBuffer;
DriverEntry->NumberOfPage = PageCount;
//
// Allocate a Loaded Image Protocol in EfiBootServicesData
//
Status = gBS->AllocatePool (EfiBootServicesData, sizeof (EFI_LOADED_IMAGE_PROTOCOL), (VOID **)&DriverEntry->LoadedImage);
if (EFI_ERROR (Status)) {
if (Buffer != NULL) {
Status = gBS->FreePool (Buffer);
}
SmmFreePages (DstBuffer, PageCount);
return Status;
}
//
// Fill in the remaining fields of the Loaded Image Protocol instance.
// Note: ImageBase is an SMRAM address that can not be accessed outside of SMRAM if SMRAM window is closed.
//
DriverEntry->LoadedImage->Revision = EFI_LOADED_IMAGE_PROTOCOL_REVISION;
DriverEntry->LoadedImage->ParentHandle = gSmmCorePrivate->SmmIplImageHandle;
DriverEntry->LoadedImage->SystemTable = gST;
DriverEntry->LoadedImage->DeviceHandle = DeviceHandle;
//
// Make an EfiBootServicesData buffer copy of FilePath
//
Status = gBS->AllocatePool (EfiBootServicesData, GetDevicePathSize (FilePath), (VOID **)&DriverEntry->LoadedImage->FilePath);
if (EFI_ERROR (Status)) {
if (Buffer != NULL) {
Status = gBS->FreePool (Buffer);
}
SmmFreePages (DstBuffer, PageCount);
return Status;
}
CopyMem (DriverEntry->LoadedImage->FilePath, FilePath, GetDevicePathSize (FilePath));
DriverEntry->LoadedImage->ImageBase = (VOID *)(UINTN)DriverEntry->ImageBuffer;
DriverEntry->LoadedImage->ImageSize = ImageContext.ImageSize;
DriverEntry->LoadedImage->ImageCodeType = EfiRuntimeServicesCode;
DriverEntry->LoadedImage->ImageDataType = EfiRuntimeServicesData;
//
// Create a new image handle in the UEFI handle database for the SMM Driver
//
DriverEntry->ImageHandle = NULL;
Status = gBS->InstallMultipleProtocolInterfaces (
&DriverEntry->ImageHandle,
&gEfiLoadedImageProtocolGuid, DriverEntry->LoadedImage,
NULL
);
//
// Print the load address and the PDB file name if it is available
//
DEBUG_CODE_BEGIN ();
UINTN Index;
UINTN StartIndex;
CHAR8 EfiFileName[256];
DEBUG ((DEBUG_INFO | DEBUG_LOAD,
"Loading SMM driver at 0x%11p EntryPoint=0x%11p ",
(VOID *)(UINTN) ImageContext.ImageAddress,
FUNCTION_ENTRY_POINT (ImageContext.EntryPoint)));
//
// Print Module Name by Pdb file path.
// Windows and Unix style file path are all trimmed correctly.
//
if (ImageContext.PdbPointer != NULL) {
StartIndex = 0;
for (Index = 0; ImageContext.PdbPointer[Index] != 0; Index++) {
if ((ImageContext.PdbPointer[Index] == '\\') || (ImageContext.PdbPointer[Index] == '/')) {
StartIndex = Index + 1;
}
}
//
// Copy the PDB file name to our temporary string, and replace .pdb with .efi
// The PDB file name is limited in the range of 0~255.
// If the length is bigger than 255, trim the redudant characters to avoid overflow in array boundary.
//
for (Index = 0; Index < sizeof (EfiFileName) - 4; Index++) {
EfiFileName[Index] = ImageContext.PdbPointer[Index + StartIndex];
if (EfiFileName[Index] == 0) {
EfiFileName[Index] = '.';
}
if (EfiFileName[Index] == '.') {
EfiFileName[Index + 1] = 'e';
EfiFileName[Index + 2] = 'f';
EfiFileName[Index + 3] = 'i';
EfiFileName[Index + 4] = 0;
break;
}
}
if (Index == sizeof (EfiFileName) - 4) {
EfiFileName[Index] = 0;
}
DEBUG ((DEBUG_INFO | DEBUG_LOAD, "%a", EfiFileName)); // &Image->ImageContext.PdbPointer[StartIndex]));
}
DEBUG ((DEBUG_INFO | DEBUG_LOAD, "\n"));
DEBUG_CODE_END ();
//
// Free buffer allocated by Fv->ReadSection.
//
// The UEFI Boot Services FreePool() function must be used because Fv->ReadSection
// used the UEFI Boot Services AllocatePool() function
//
Status = gBS->FreePool(Buffer);
return Status;
}
/**
Preprocess dependency expression and update DriverEntry to reflect the
state of Before and After dependencies. If DriverEntry->Before
or DriverEntry->After is set it will never be cleared.
@param DriverEntry DriverEntry element to update .
@retval EFI_SUCCESS It always works.
**/
EFI_STATUS
SmmPreProcessDepex (
IN EFI_SMM_DRIVER_ENTRY *DriverEntry
)
{
UINT8 *Iterator;
Iterator = DriverEntry->Depex;
DriverEntry->Dependent = TRUE;
if (*Iterator == EFI_DEP_BEFORE) {
DriverEntry->Before = TRUE;
} else if (*Iterator == EFI_DEP_AFTER) {
DriverEntry->After = TRUE;
}
if (DriverEntry->Before || DriverEntry->After) {
CopyMem (&DriverEntry->BeforeAfterGuid, Iterator + 1, sizeof (EFI_GUID));
}
return EFI_SUCCESS;
}
/**
Read Depex and pre-process the Depex for Before and After. If Section Extraction
protocol returns an error via ReadSection defer the reading of the Depex.
@param DriverEntry Driver to work on.
@retval EFI_SUCCESS Depex read and preprossesed
@retval EFI_PROTOCOL_ERROR The section extraction protocol returned an error
and Depex reading needs to be retried.
@retval Error DEPEX not found.
**/
EFI_STATUS
SmmGetDepexSectionAndPreProccess (
IN EFI_SMM_DRIVER_ENTRY *DriverEntry
)
{
EFI_STATUS Status;
EFI_SECTION_TYPE SectionType;
UINT32 AuthenticationStatus;
EFI_FIRMWARE_VOLUME2_PROTOCOL *Fv;
Fv = DriverEntry->Fv;
//
// Grab Depex info, it will never be free'ed.
// (Note: DriverEntry->Depex is in DXE memory)
//
SectionType = EFI_SECTION_SMM_DEPEX;
Status = Fv->ReadSection (
DriverEntry->Fv,
&DriverEntry->FileName,
SectionType,
0,
&DriverEntry->Depex,
(UINTN *)&DriverEntry->DepexSize,
&AuthenticationStatus
);
if (EFI_ERROR (Status)) {
if (Status == EFI_PROTOCOL_ERROR) {
//
// The section extraction protocol failed so set protocol error flag
//
DriverEntry->DepexProtocolError = TRUE;
} else {
//
// If no Depex assume depend on all architectural protocols
//
DriverEntry->Depex = NULL;
DriverEntry->Dependent = TRUE;
DriverEntry->DepexProtocolError = FALSE;
}
} else {
//
// Set Before and After state information based on Depex
// Driver will be put in Dependent state
//
SmmPreProcessDepex (DriverEntry);
DriverEntry->DepexProtocolError = FALSE;
}
return Status;
}
/**
This is the main Dispatcher for SMM and it exits when there are no more
drivers to run. Drain the mScheduledQueue and load and start a PE
image for each driver. Search the mDiscoveredList to see if any driver can
be placed on the mScheduledQueue. If no drivers are placed on the
mScheduledQueue exit the function. On exit it is assumed the Bds()
will be called, and when the Bds() exits the Dispatcher will be called
again.
@retval EFI_ALREADY_STARTED The SMM Dispatcher is already running
@retval EFI_NOT_FOUND No SMM Drivers were dispatched
@retval EFI_SUCCESS One or more SMM Drivers were dispatched
**/
EFI_STATUS
SmmDispatcher (
VOID
)
{
EFI_STATUS Status;
EFI_STATUS ReturnStatus;
LIST_ENTRY *Link;
EFI_SMM_DRIVER_ENTRY *DriverEntry;
BOOLEAN ReadyToRun;
if (!gRequestDispatch) {
return EFI_NOT_FOUND;
}
if (gDispatcherRunning) {
//
// If the dispatcher is running don't let it be restarted.
//
return EFI_ALREADY_STARTED;
}
gDispatcherRunning = TRUE;
ReturnStatus = EFI_NOT_FOUND;
do {
//
// Drain the Scheduled Queue
//
while (!IsListEmpty (&mScheduledQueue)) {
DriverEntry = CR (
mScheduledQueue.ForwardLink,
EFI_SMM_DRIVER_ENTRY,
ScheduledLink,
EFI_SMM_DRIVER_ENTRY_SIGNATURE
);
//
// Load the SMM Driver image into memory. If the Driver was transitioned from
// Untrused to Scheduled it would have already been loaded so we may need to
// skip the LoadImage
//
if (DriverEntry->ImageHandle == NULL) {
Status = SmmLoadImage (DriverEntry);
//
// Update the driver state to reflect that it's been loaded
//
if (EFI_ERROR (Status)) {
//
// The SMM Driver could not be loaded, and do not attempt to load or start it again.
// Take driver from Scheduled to Initialized.
//
DriverEntry->Initialized = TRUE;
DriverEntry->Scheduled = FALSE;
RemoveEntryList (&DriverEntry->ScheduledLink);
//
// If it's an error don't try the StartImage
//
continue;
}
}
DriverEntry->Scheduled = FALSE;
DriverEntry->Initialized = TRUE;
RemoveEntryList (&DriverEntry->ScheduledLink);
REPORT_STATUS_CODE_WITH_EXTENDED_DATA (
EFI_PROGRESS_CODE,
EFI_SOFTWARE_SMM_DRIVER | EFI_SW_PC_INIT_BEGIN,
&DriverEntry->ImageHandle,
sizeof (DriverEntry->ImageHandle)
);
//
// For each SMM driver, pass NULL as ImageHandle
//
Status = ((EFI_IMAGE_ENTRY_POINT)(UINTN)DriverEntry->ImageEntryPoint)(DriverEntry->ImageHandle, gST);
if (EFI_ERROR(Status)){
SmmFreePages(DriverEntry->ImageBuffer, DriverEntry->NumberOfPage);
}
REPORT_STATUS_CODE_WITH_EXTENDED_DATA (
EFI_PROGRESS_CODE,
EFI_SOFTWARE_SMM_DRIVER | EFI_SW_PC_INIT_END,
&DriverEntry->ImageHandle,
sizeof (DriverEntry->ImageHandle)
);
ReturnStatus = EFI_SUCCESS;
}
//
// Search DriverList for items to place on Scheduled Queue
//
ReadyToRun = FALSE;
for (Link = mDiscoveredList.ForwardLink; Link != &mDiscoveredList; Link = Link->ForwardLink) {
DriverEntry = CR (Link, EFI_SMM_DRIVER_ENTRY, Link, EFI_SMM_DRIVER_ENTRY_SIGNATURE);
if (DriverEntry->DepexProtocolError){
//
// If Section Extraction Protocol did not let the Depex be read before retry the read
//
Status = SmmGetDepexSectionAndPreProccess (DriverEntry);
}
if (DriverEntry->Dependent) {
if (SmmIsSchedulable (DriverEntry)) {
SmmInsertOnScheduledQueueWhileProcessingBeforeAndAfter (DriverEntry);
ReadyToRun = TRUE;
}
}
}
} while (ReadyToRun);
//
// If there is no more SMM driver to dispatch, stop the dispatch request
//
gRequestDispatch = FALSE;
for (Link = mDiscoveredList.ForwardLink; Link != &mDiscoveredList; Link = Link->ForwardLink) {
DriverEntry = CR (Link, EFI_SMM_DRIVER_ENTRY, Link, EFI_SMM_DRIVER_ENTRY_SIGNATURE);
if (!DriverEntry->Initialized){
//
// We have SMM driver pending to dispatch
//
gRequestDispatch = TRUE;
break;
}
}
gDispatcherRunning = FALSE;
return ReturnStatus;
}
/**
Insert InsertedDriverEntry onto the mScheduledQueue. To do this you
must add any driver with a before dependency on InsertedDriverEntry first.
You do this by recursively calling this routine. After all the Befores are
processed you can add InsertedDriverEntry to the mScheduledQueue.
Then you can add any driver with an After dependency on InsertedDriverEntry
by recursively calling this routine.
@param InsertedDriverEntry The driver to insert on the ScheduledLink Queue
**/
VOID
SmmInsertOnScheduledQueueWhileProcessingBeforeAndAfter (
IN EFI_SMM_DRIVER_ENTRY *InsertedDriverEntry
)
{
LIST_ENTRY *Link;
EFI_SMM_DRIVER_ENTRY *DriverEntry;
//
// Process Before Dependency
//
for (Link = mDiscoveredList.ForwardLink; Link != &mDiscoveredList; Link = Link->ForwardLink) {
DriverEntry = CR(Link, EFI_SMM_DRIVER_ENTRY, Link, EFI_SMM_DRIVER_ENTRY_SIGNATURE);
if (DriverEntry->Before && DriverEntry->Dependent && DriverEntry != InsertedDriverEntry) {
DEBUG ((DEBUG_DISPATCH, "Evaluate SMM DEPEX for FFS(%g)\n", &DriverEntry->FileName));
DEBUG ((DEBUG_DISPATCH, " BEFORE FFS(%g) = ", &DriverEntry->BeforeAfterGuid));
if (CompareGuid (&InsertedDriverEntry->FileName, &DriverEntry->BeforeAfterGuid)) {
//
// Recursively process BEFORE
//
DEBUG ((DEBUG_DISPATCH, "TRUE\n END\n RESULT = TRUE\n"));
SmmInsertOnScheduledQueueWhileProcessingBeforeAndAfter (DriverEntry);
} else {
DEBUG ((DEBUG_DISPATCH, "FALSE\n END\n RESULT = FALSE\n"));
}
}
}
//
// Convert driver from Dependent to Scheduled state
//
InsertedDriverEntry->Dependent = FALSE;
InsertedDriverEntry->Scheduled = TRUE;
InsertTailList (&mScheduledQueue, &InsertedDriverEntry->ScheduledLink);
//
// Process After Dependency
//
for (Link = mDiscoveredList.ForwardLink; Link != &mDiscoveredList; Link = Link->ForwardLink) {
DriverEntry = CR(Link, EFI_SMM_DRIVER_ENTRY, Link, EFI_SMM_DRIVER_ENTRY_SIGNATURE);
if (DriverEntry->After && DriverEntry->Dependent && DriverEntry != InsertedDriverEntry) {
DEBUG ((DEBUG_DISPATCH, "Evaluate SMM DEPEX for FFS(%g)\n", &DriverEntry->FileName));
DEBUG ((DEBUG_DISPATCH, " AFTER FFS(%g) = ", &DriverEntry->BeforeAfterGuid));
if (CompareGuid (&InsertedDriverEntry->FileName, &DriverEntry->BeforeAfterGuid)) {
//
// Recursively process AFTER
//
DEBUG ((DEBUG_DISPATCH, "TRUE\n END\n RESULT = TRUE\n"));
SmmInsertOnScheduledQueueWhileProcessingBeforeAndAfter (DriverEntry);
} else {
DEBUG ((DEBUG_DISPATCH, "FALSE\n END\n RESULT = FALSE\n"));
}
}
}
}
/**
Return TRUE if the Fv has been processed, FALSE if not.
@param FvHandle The handle of a FV that's being tested
@retval TRUE Fv protocol on FvHandle has been processed
@retval FALSE Fv protocol on FvHandle has not yet been
processed
**/
BOOLEAN
FvHasBeenProcessed (
IN EFI_HANDLE FvHandle
)
{
LIST_ENTRY *Link;
KNOWN_HANDLE *KnownHandle;
for (Link = mFvHandleList.ForwardLink; Link != &mFvHandleList; Link = Link->ForwardLink) {
KnownHandle = CR(Link, KNOWN_HANDLE, Link, KNOWN_HANDLE_SIGNATURE);
if (KnownHandle->Handle == FvHandle) {
return TRUE;
}
}
return FALSE;
}
/**
Remember that Fv protocol on FvHandle has had it's drivers placed on the
mDiscoveredList. This fucntion adds entries on the mFvHandleList. Items are
never removed/freed from the mFvHandleList.
@param FvHandle The handle of a FV that has been processed
**/
VOID
FvIsBeingProcesssed (
IN EFI_HANDLE FvHandle
)
{
KNOWN_HANDLE *KnownHandle;
KnownHandle = AllocatePool (sizeof (KNOWN_HANDLE));
ASSERT (KnownHandle != NULL);
KnownHandle->Signature = KNOWN_HANDLE_SIGNATURE;
KnownHandle->Handle = FvHandle;
InsertTailList (&mFvHandleList, &KnownHandle->Link);
}
/**
Convert FvHandle and DriverName into an EFI device path
@param Fv Fv protocol, needed to read Depex info out of
FLASH.
@param FvHandle Handle for Fv, needed in the
EFI_SMM_DRIVER_ENTRY so that the PE image can be
read out of the FV at a later time.
@param DriverName Name of driver to add to mDiscoveredList.
@return Pointer to device path constructed from FvHandle and DriverName
**/
EFI_DEVICE_PATH_PROTOCOL *
SmmFvToDevicePath (
IN EFI_FIRMWARE_VOLUME2_PROTOCOL *Fv,
IN EFI_HANDLE FvHandle,
IN EFI_GUID *DriverName
)
{
EFI_STATUS Status;
EFI_DEVICE_PATH_PROTOCOL *FvDevicePath;
EFI_DEVICE_PATH_PROTOCOL *FileNameDevicePath;
//
// Remember the device path of the FV
//
Status = gBS->HandleProtocol (FvHandle, &gEfiDevicePathProtocolGuid, (VOID **)&FvDevicePath);
if (EFI_ERROR (Status)) {
FileNameDevicePath = NULL;
} else {
//
// Build a device path to the file in the FV to pass into gBS->LoadImage
//
EfiInitializeFwVolDevicepathNode (&mFvDevicePath.File, DriverName);
SetDevicePathEndNode (&mFvDevicePath.End);
//
// Note: FileNameDevicePath is in DXE memory
//
FileNameDevicePath = AppendDevicePath (
FvDevicePath,
(EFI_DEVICE_PATH_PROTOCOL *)&mFvDevicePath
);
}
return FileNameDevicePath;
}
/**
Add an entry to the mDiscoveredList. Allocate memory to store the DriverEntry,
and initilize any state variables. Read the Depex from the FV and store it
in DriverEntry. Pre-process the Depex to set the Before and After state.
The Discovered list is never free'ed and contains booleans that represent the
other possible SMM driver states.
@param Fv Fv protocol, needed to read Depex info out of
FLASH.
@param FvHandle Handle for Fv, needed in the
EFI_SMM_DRIVER_ENTRY so that the PE image can be
read out of the FV at a later time.
@param DriverName Name of driver to add to mDiscoveredList.
@retval EFI_SUCCESS If driver was added to the mDiscoveredList.
@retval EFI_ALREADY_STARTED The driver has already been started. Only one
DriverName may be active in the system at any one
time.
**/
EFI_STATUS
SmmAddToDriverList (
IN EFI_FIRMWARE_VOLUME2_PROTOCOL *Fv,
IN EFI_HANDLE FvHandle,
IN EFI_GUID *DriverName
)
{
EFI_SMM_DRIVER_ENTRY *DriverEntry;
//
// Create the Driver Entry for the list. ZeroPool initializes lots of variables to
// NULL or FALSE.
//
DriverEntry = AllocateZeroPool (sizeof (EFI_SMM_DRIVER_ENTRY));
ASSERT (DriverEntry != NULL);
DriverEntry->Signature = EFI_SMM_DRIVER_ENTRY_SIGNATURE;
CopyGuid (&DriverEntry->FileName, DriverName);
DriverEntry->FvHandle = FvHandle;
DriverEntry->Fv = Fv;
DriverEntry->FvFileDevicePath = SmmFvToDevicePath (Fv, FvHandle, DriverName);
SmmGetDepexSectionAndPreProccess (DriverEntry);
InsertTailList (&mDiscoveredList, &DriverEntry->Link);
gRequestDispatch = TRUE;
return EFI_SUCCESS;
}
/**
This function is the main entry point for an SMM handler dispatch
or communicate-based callback.
Event notification that is fired every time a FV dispatch protocol is added.
More than one protocol may have been added when this event is fired, so you
must loop on SmmLocateHandle () to see how many protocols were added and
do the following to each FV:
If the Fv has already been processed, skip it. If the Fv has not been
processed then mark it as being processed, as we are about to process it.
Read the Fv and add any driver in the Fv to the mDiscoveredList.The
mDiscoveredList is never free'ed and contains variables that define
the other states the SMM driver transitions to..
While you are at it read the A Priori file into memory.
Place drivers in the A Priori list onto the mScheduledQueue.
@param DispatchHandle The unique handle assigned to this handler by SmiHandlerRegister().
@param Context Points to an optional handler context which was specified when the handler was registered.
@param CommBuffer A pointer to a collection of data in memory that will
be conveyed from a non-SMM environment into an SMM environment.
@param CommBufferSize The size of the CommBuffer.
@return Status Code
**/
EFI_STATUS
EFIAPI
SmmDriverDispatchHandler (
IN EFI_HANDLE DispatchHandle,
IN CONST VOID *Context, OPTIONAL
IN OUT VOID *CommBuffer, OPTIONAL
IN OUT UINTN *CommBufferSize OPTIONAL
)
{
EFI_STATUS Status;
UINTN HandleCount;
EFI_HANDLE *HandleBuffer;
EFI_STATUS GetNextFileStatus;
EFI_STATUS SecurityStatus;
EFI_FIRMWARE_VOLUME2_PROTOCOL *Fv;
EFI_DEVICE_PATH_PROTOCOL *FvDevicePath;
EFI_HANDLE FvHandle;
EFI_GUID NameGuid;
UINTN Key;
EFI_FV_FILETYPE Type;
EFI_FV_FILE_ATTRIBUTES Attributes;
UINTN Size;
EFI_SMM_DRIVER_ENTRY *DriverEntry;
EFI_GUID *AprioriFile;
UINTN AprioriEntryCount;
UINTN Index;
LIST_ENTRY *Link;
UINT32 AuthenticationStatus;
UINTN SizeOfBuffer;
HandleBuffer = NULL;
Status = gBS->LocateHandleBuffer (
ByProtocol,
&gEfiFirmwareVolume2ProtocolGuid,
NULL,
&HandleCount,
&HandleBuffer
);
if (EFI_ERROR (Status)) {
return EFI_NOT_FOUND;
}
for (Index = 0; Index < HandleCount; Index++) {
FvHandle = HandleBuffer[Index];
if (FvHasBeenProcessed (FvHandle)) {
//
// This Fv has already been processed so lets skip it!
//
continue;
}
//
// Since we are about to process this Fv mark it as processed.
//
FvIsBeingProcesssed (FvHandle);
Status = gBS->HandleProtocol (FvHandle, &gEfiFirmwareVolume2ProtocolGuid, (VOID **)&Fv);
if (EFI_ERROR (Status)) {
//
// FvHandle must have a Firmware Volume2 Protocol thus we should never get here.
//
ASSERT (FALSE);
continue;
}
Status = gBS->HandleProtocol (FvHandle, &gEfiDevicePathProtocolGuid, (VOID **)&FvDevicePath);
if (EFI_ERROR (Status)) {
//
// The Firmware volume doesn't have device path, can't be dispatched.
//
continue;
}
//
// If the Security Architectural Protocol has not been located yet, then attempt to locate it
//
if (mSecurity == NULL) {
gBS->LocateProtocol (&gEfiSecurityArchProtocolGuid, NULL, (VOID**)&mSecurity);
}
//
// Evaluate the authentication status of the Firmware Volume through
// Security Architectural Protocol
//
if (mSecurity != NULL) {
SecurityStatus = mSecurity->FileAuthenticationState (
mSecurity,
0,
FvDevicePath
);
if (SecurityStatus != EFI_SUCCESS) {
//
// Security check failed. The firmware volume should not be used for any purpose.
//
continue;
}
}
//
// Discover Drivers in FV and add them to the Discovered Driver List.
// Process EFI_FV_FILETYPE_SMM type and then EFI_FV_FILETYPE_COMBINED_SMM_DXE
//
for (Index = 0; Index < sizeof (mSmmFileTypes)/sizeof (EFI_FV_FILETYPE); Index++) {
//
// Initialize the search key
//
Key = 0;
do {
Type = mSmmFileTypes[Index];
GetNextFileStatus = Fv->GetNextFile (
Fv,
&Key,
&Type,
&NameGuid,
&Attributes,
&Size
);
if (!EFI_ERROR (GetNextFileStatus)) {
SmmAddToDriverList (Fv, FvHandle, &NameGuid);
}
} while (!EFI_ERROR (GetNextFileStatus));
}
//
// Read the array of GUIDs from the Apriori file if it is present in the firmware volume
// (Note: AprioriFile is in DXE memory)
//
AprioriFile = NULL;
Status = Fv->ReadSection (
Fv,
&gAprioriGuid,
EFI_SECTION_RAW,
0,
(VOID **)&AprioriFile,
&SizeOfBuffer,
&AuthenticationStatus
);
if (!EFI_ERROR (Status)) {
AprioriEntryCount = SizeOfBuffer / sizeof (EFI_GUID);
} else {
AprioriEntryCount = 0;
}
//
// Put drivers on Apriori List on the Scheduled queue. The Discovered List includes
// drivers not in the current FV and these must be skipped since the a priori list
// is only valid for the FV that it resided in.
//
for (Index = 0; Index < AprioriEntryCount; Index++) {
for (Link = mDiscoveredList.ForwardLink; Link != &mDiscoveredList; Link = Link->ForwardLink) {
DriverEntry = CR(Link, EFI_SMM_DRIVER_ENTRY, Link, EFI_SMM_DRIVER_ENTRY_SIGNATURE);
if (CompareGuid (&DriverEntry->FileName, &AprioriFile[Index]) &&
(FvHandle == DriverEntry->FvHandle)) {
DriverEntry->Dependent = FALSE;
DriverEntry->Scheduled = TRUE;
InsertTailList (&mScheduledQueue, &DriverEntry->ScheduledLink);
DEBUG ((DEBUG_DISPATCH, "Evaluate SMM DEPEX for FFS(%g)\n", &DriverEntry->FileName));
DEBUG ((DEBUG_DISPATCH, " RESULT = TRUE (Apriori)\n"));
break;
}
}
}
//
// Free data allocated by Fv->ReadSection ()
//
// The UEFI Boot Services FreePool() function must be used because Fv->ReadSection
// used the UEFI Boot Services AllocatePool() function
//
gBS->FreePool (AprioriFile);
}
//
// Execute the SMM Dispatcher on any newly discovered FVs and previously
// discovered SMM drivers that have been discovered but not dispatched.
//
return SmmDispatcher ();
}
/**
Traverse the discovered list for any drivers that were discovered but not loaded
because the dependency experessions evaluated to false.
**/
VOID
SmmDisplayDiscoveredNotDispatched (
VOID
)
{
LIST_ENTRY *Link;
EFI_SMM_DRIVER_ENTRY *DriverEntry;
for (Link = mDiscoveredList.ForwardLink;Link !=&mDiscoveredList; Link = Link->ForwardLink) {
DriverEntry = CR(Link, EFI_SMM_DRIVER_ENTRY, Link, EFI_SMM_DRIVER_ENTRY_SIGNATURE);
if (DriverEntry->Dependent) {
DEBUG ((DEBUG_LOAD, "SMM Driver %g was discovered but not loaded!!\n", &DriverEntry->FileName));
}
}
}
|