summaryrefslogtreecommitdiff
path: root/SecurityPkg/Tcg/TcgDxe/TcgDxe.c
blob: 05a11360d46b16d3339c9ec580c0619227da23d7 (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
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
/** @file  
  This module implements TCG EFI Protocol.
  
Copyright (c) 2005 - 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 <PiDxe.h>
#include <IndustryStandard/Tpm12.h>
#include <IndustryStandard/Acpi.h>
#include <IndustryStandard/PeImage.h>
#include <IndustryStandard/SmBios.h>

#include <Guid/GlobalVariable.h>
#include <Guid/SmBios.h>
#include <Guid/HobList.h>
#include <Guid/TcgEventHob.h>
#include <Guid/EventGroup.h>
#include <Protocol/DevicePath.h>
#include <Protocol/TcgService.h>
#include <Protocol/AcpiTable.h>

#include <Library/DebugLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/UefiRuntimeServicesTableLib.h>
#include <Library/UefiDriverEntryPoint.h>
#include <Library/HobLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/BaseLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/PrintLib.h>
#include <Library/TpmCommLib.h>
#include <Library/PcdLib.h>
#include <Library/UefiLib.h>

#include "TpmComm.h"

#define  EFI_TCG_LOG_AREA_SIZE        0x10000

#pragma pack (1)

typedef struct _EFI_TCG_CLIENT_ACPI_TABLE {
  EFI_ACPI_DESCRIPTION_HEADER       Header;
  UINT16                            PlatformClass;
  UINT32                            Laml;
  EFI_PHYSICAL_ADDRESS              Lasa;
} EFI_TCG_CLIENT_ACPI_TABLE;

typedef struct _EFI_TCG_SERVER_ACPI_TABLE {
  EFI_ACPI_DESCRIPTION_HEADER             Header;
  UINT16                                  PlatformClass;
  UINT16                                  Reserved0;
  UINT64                                  Laml;
  EFI_PHYSICAL_ADDRESS                    Lasa;
  UINT16                                  SpecRev;
  UINT8                                   DeviceFlags;
  UINT8                                   InterruptFlags;
  UINT8                                   Gpe;
  UINT8                                   Reserved1[3];
  UINT32                                  GlobalSysInt;
  EFI_ACPI_3_0_GENERIC_ADDRESS_STRUCTURE  BaseAddress;
  UINT32                                  Reserved2;
  EFI_ACPI_3_0_GENERIC_ADDRESS_STRUCTURE  ConfigAddress;
  UINT8                                   PciSegNum;
  UINT8                                   PciBusNum;
  UINT8                                   PciDevNum;
  UINT8                                   PciFuncNum;
} EFI_TCG_SERVER_ACPI_TABLE;

#pragma pack ()

#define TCG_DXE_DATA_FROM_THIS(this)  \
  BASE_CR (this, TCG_DXE_DATA, TcgProtocol)

typedef struct _TCG_DXE_DATA {
  EFI_TCG_PROTOCOL                  TcgProtocol;
  TCG_EFI_BOOT_SERVICE_CAPABILITY   BsCap;
  EFI_TCG_CLIENT_ACPI_TABLE         *TcgClientAcpiTable;
  EFI_TCG_SERVER_ACPI_TABLE         *TcgServerAcpiTable;
  UINTN                             EventLogSize;
  UINT8                             *LastEvent;
  TIS_TPM_HANDLE                    TpmHandle;
} TCG_DXE_DATA;



EFI_TCG_CLIENT_ACPI_TABLE           mTcgClientAcpiTemplate = {
  {
    EFI_ACPI_3_0_TRUSTED_COMPUTING_PLATFORM_ALLIANCE_CAPABILITIES_TABLE_SIGNATURE,
    sizeof (mTcgClientAcpiTemplate),
    0x02                      //Revision
    //
    // Compiler initializes the remaining bytes to 0
    // These fields should be filled in in production
    //
  },
  0,                          // 0 for PC Client Platform Class
  0,                          // Log Area Max Length
  (EFI_PHYSICAL_ADDRESS) (SIZE_4GB - 1)  // Log Area Start Address
};

//
// The following EFI_TCG_SERVER_ACPI_TABLE default setting is just one example,
// the TPM device connectes to LPC, and also defined the ACPI _UID as 0xFF,
// this _UID can be changed and should match with the _UID setting of the TPM 
// ACPI device object  
//
EFI_TCG_SERVER_ACPI_TABLE           mTcgServerAcpiTemplate = {
  {
    EFI_ACPI_3_0_TRUSTED_COMPUTING_PLATFORM_ALLIANCE_CAPABILITIES_TABLE_SIGNATURE,
    sizeof (mTcgServerAcpiTemplate),
    0x02                      //Revision
    //
    // Compiler initializes the remaining bytes to 0
    // These fields should be filled in in production
    //
  },
  1,                          // 1 for Server Platform Class
  0,                          // Reserved
  0,                          // Log Area Max Length
  (EFI_PHYSICAL_ADDRESS) (SIZE_4GB - 1), // Log Area Start Address
  0x0100,                     // TCG Specification revision 1.0
  2,                          // Device Flags
  0,                          // Interrupt Flags
  0,                          // GPE
  {0},                        // Reserved 3 bytes
  0,                          // Global System Interrupt
  {
    EFI_ACPI_3_0_SYSTEM_MEMORY,
    0,
    0,
    EFI_ACPI_3_0_BYTE,
    TPM_BASE_ADDRESS          // Base Address
  },
  0,                          // Reserved
  {0},                        // Configuration Address
  0xFF,                       // ACPI _UID value of the device, can be changed for different platforms
  0,                          // ACPI _UID value of the device, can be changed for different platforms
  0,                          // ACPI _UID value of the device, can be changed for different platforms
  0                           // ACPI _UID value of the device, can be changed for different platforms
};

UINTN  mBootAttempts  = 0;
CHAR16 mBootVarName[] = L"BootOrder";

/**
  This service provides EFI protocol capability information, state information 
  about the TPM, and Event Log state information.

  @param[in]  This               Indicates the calling context
  @param[out] ProtocolCapability The callee allocates memory for a TCG_BOOT_SERVICE_CAPABILITY 
                                 structure and fills in the fields with the EFI protocol 
                                 capability information and the current TPM state information.
  @param[out] TCGFeatureFlags    This is a pointer to the feature flags. No feature 
                                 flags are currently defined so this parameter 
                                 MUST be set to 0. However, in the future, 
                                 feature flags may be defined that, for example, 
                                 enable hash algorithm agility.
  @param[out] EventLogLocation   This is a pointer to the address of the event log in memory.
  @param[out] EventLogLastEntry  If the Event Log contains more than one entry, 
                                 this is a pointer to the address of the start of 
                                 the last entry in the event log in memory. 

  @retval EFI_SUCCESS            Operation completed successfully.
  @retval EFI_INVALID_PARAMETER  ProtocolCapability does not match TCG capability.
  
**/
EFI_STATUS
EFIAPI
TcgDxeStatusCheck (
  IN      EFI_TCG_PROTOCOL                 *This,
  OUT     TCG_EFI_BOOT_SERVICE_CAPABILITY  *ProtocolCapability,
  OUT     UINT32                           *TCGFeatureFlags,
  OUT     EFI_PHYSICAL_ADDRESS             *EventLogLocation,
  OUT     EFI_PHYSICAL_ADDRESS             *EventLogLastEntry
  )
{
  TCG_DXE_DATA                      *TcgData;

  TcgData = TCG_DXE_DATA_FROM_THIS (This);

  if (ProtocolCapability != NULL) {
    *ProtocolCapability = TcgData->BsCap;
  }

  if (TCGFeatureFlags != NULL) {
    *TCGFeatureFlags = 0;
  }

  if (EventLogLocation != NULL) {
    if (PcdGet8 (PcdTpmPlatformClass) == TCG_PLATFORM_TYPE_CLIENT) {
      *EventLogLocation = TcgData->TcgClientAcpiTable->Lasa;
    } else {
      *EventLogLocation = TcgData->TcgServerAcpiTable->Lasa;
    }
  }

  if (EventLogLastEntry != NULL) {
    if (TcgData->BsCap.TPMDeactivatedFlag) {
      *EventLogLastEntry = (EFI_PHYSICAL_ADDRESS)(UINTN)0;
    } else {
      *EventLogLastEntry = (EFI_PHYSICAL_ADDRESS)(UINTN)TcgData->LastEvent;
    }
  }

  return EFI_SUCCESS;
}

/**
  This service abstracts the capability to do a hash operation on a data buffer.
  
  @param[in]      This             Indicates the calling context
  @param[in]      HashData         Pointer to the data buffer to be hashed
  @param[in]      HashDataLen      Length of the data buffer to be hashed
  @param[in]      AlgorithmId      Identification of the Algorithm to use for the hashing operation
  @param[in, out] HashedDataLen    Resultant length of the hashed data
  @param[in, out] HashedDataResult Resultant buffer of the hashed data  
  
  @retval EFI_SUCCESS              Operation completed successfully.
  @retval EFI_INVALID_PARAMETER    HashDataLen is NULL.
  @retval EFI_INVALID_PARAMETER    HashDataLenResult is NULL.
  @retval EFI_OUT_OF_RESOURCES     Cannot allocate buffer of size *HashedDataLen.
  @retval EFI_UNSUPPORTED          AlgorithmId not supported.
  @retval EFI_BUFFER_TOO_SMALL     *HashedDataLen < sizeof (TCG_DIGEST).
  
**/
EFI_STATUS
EFIAPI
TcgDxeHashAll (
  IN      EFI_TCG_PROTOCOL          *This,
  IN      UINT8                     *HashData,
  IN      UINT64                    HashDataLen,
  IN      TCG_ALGORITHM_ID          AlgorithmId,
  IN OUT  UINT64                    *HashedDataLen,
  IN OUT  UINT8                     **HashedDataResult
  )
{
  if (HashedDataLen == NULL || HashedDataResult == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  switch (AlgorithmId) {
    case TPM_ALG_SHA:
      if (*HashedDataLen == 0) {
        *HashedDataLen    = sizeof (TPM_DIGEST);
        *HashedDataResult = AllocatePool ((UINTN) *HashedDataLen);
        if (*HashedDataResult == NULL) {
          return EFI_OUT_OF_RESOURCES;
        }
      }

      if (*HashedDataLen < sizeof (TPM_DIGEST)) {
        *HashedDataLen = sizeof (TPM_DIGEST);
        return EFI_BUFFER_TOO_SMALL;
      }
      *HashedDataLen = sizeof (TPM_DIGEST);

      return TpmCommHashAll (
               HashData,
               (UINTN) HashDataLen,
               (TPM_DIGEST*)*HashedDataResult
               );
    default:
      return EFI_UNSUPPORTED;
  }
}

/**
  Add a new entry to the Event Log.

  @param[in] TcgData       TCG_DXE_DATA structure.
  @param[in] NewEventHdr   Pointer to a TCG_PCR_EVENT_HDR data structure.  
  @param[in] NewEventData  Pointer to the new event data.  
  
  @retval EFI_SUCCESS           The new event log entry was added.
  @retval EFI_OUT_OF_RESOURCES  No enough memory to log the new event.

**/
EFI_STATUS
EFIAPI
TcgDxeLogEventI (
  IN      TCG_DXE_DATA              *TcgData,
  IN      TCG_PCR_EVENT_HDR         *NewEventHdr,
  IN      UINT8                     *NewEventData
  )
{
  if (PcdGet8 (PcdTpmPlatformClass) == TCG_PLATFORM_TYPE_CLIENT) {
    TcgData->LastEvent = (UINT8*)(UINTN)TcgData->TcgClientAcpiTable->Lasa;
    return TpmCommLogEvent (
             &TcgData->LastEvent,
             &TcgData->EventLogSize,
             (UINTN)TcgData->TcgClientAcpiTable->Laml,
             NewEventHdr,
             NewEventData
             );
  } else {
    TcgData->LastEvent = (UINT8*)(UINTN)TcgData->TcgServerAcpiTable->Lasa;
    return TpmCommLogEvent (
             &TcgData->LastEvent,
             &TcgData->EventLogSize,
             (UINTN)TcgData->TcgServerAcpiTable->Laml,
             NewEventHdr,
             NewEventData
             );
  }
}

/**
  This service abstracts the capability to add an entry to the Event Log.

  @param[in]      This           Indicates the calling context
  @param[in]      TCGLogData     Pointer to the start of the data buffer containing 
                                 the TCG_PCR_EVENT data structure. All fields in 
                                 this structure are properly filled by the caller.
  @param[in, out] EventNumber    The event number of the event just logged
  @param[in]      Flags          Indicate additional flags. Only one flag has been 
                                 defined at this time, which is 0x01 and means the 
                                 extend operation should not be performed. All 
                                 other bits are reserved. 
 
  @retval EFI_SUCCESS            Operation completed successfully.
  @retval EFI_OUT_OF_RESOURCES   Insufficient memory in the event log to complete this action.
  
**/
EFI_STATUS
EFIAPI
TcgDxeLogEvent (
  IN      EFI_TCG_PROTOCOL          *This,
  IN      TCG_PCR_EVENT             *TCGLogData,
  IN OUT  UINT32                    *EventNumber,
  IN      UINT32                    Flags
  )
{
  TCG_DXE_DATA  *TcgData;

  TcgData = TCG_DXE_DATA_FROM_THIS (This);
  
  if (TcgData->BsCap.TPMDeactivatedFlag) {
    return EFI_DEVICE_ERROR;
  }
  return TcgDxeLogEventI (
           TcgData,
           (TCG_PCR_EVENT_HDR*)TCGLogData,
           TCGLogData->Event
           );
}

/**
  This service is a proxy for commands to the TPM.

  @param[in]  This                        Indicates the calling context
  @param[in]  TpmInputParameterBlockSize  Size of the TPM input parameter block
  @param[in]  TpmInputParameterBlock      Pointer to the TPM input parameter block
  @param[in]  TpmOutputParameterBlockSize Size of the TPM output parameter block
  @param[in]  TpmOutputParameterBlock     Pointer to the TPM output parameter block

  @retval     EFI_SUCCESS                 Operation completed successfully.
  @retval     EFI_INVALID_PARAMETER       Invalid ordinal.
  @retval     EFI_UNSUPPORTED             Current Task Priority Level  >= EFI_TPL_CALLBACK.
  @retval     EFI_TIMEOUT                 The TIS timed-out.
  
**/
EFI_STATUS
EFIAPI
TcgDxePassThroughToTpm (
  IN      EFI_TCG_PROTOCOL          *This,
  IN      UINT32                    TpmInputParameterBlockSize,
  IN      UINT8                     *TpmInputParameterBlock,
  IN      UINT32                    TpmOutputParameterBlockSize,
  IN      UINT8                     *TpmOutputParameterBlock
  )
{
  TCG_DXE_DATA                      *TcgData;

  TcgData = TCG_DXE_DATA_FROM_THIS (This);

  return TisPcExecute (
           TcgData->TpmHandle,
           "%r%/%r",
           TpmInputParameterBlock,
           (UINTN) TpmInputParameterBlockSize,
           TpmOutputParameterBlock,
           (UINTN) TpmOutputParameterBlockSize
           );
}

/**
  Do a hash operation on a data buffer, extend a specific TPM PCR with the hash result,
  and add an entry to the Event Log.

  @param[in]      TcgData       TCG_DXE_DATA structure.
  @param[in]      HashData      Physical address of the start of the data buffer 
                                to be hashed, extended, and logged.
  @param[in]      HashDataLen   The length, in bytes, of the buffer referenced by HashData
  @param[in, out] NewEventHdr   Pointer to a TCG_PCR_EVENT_HDR data structure.  
  @param[in]      NewEventData  Pointer to the new event data.  

  @retval EFI_SUCCESS           Operation completed successfully.
  @retval EFI_OUT_OF_RESOURCES  No enough memory to log the new event.
  @retval EFI_DEVICE_ERROR      The command was unsuccessful.

**/
EFI_STATUS
EFIAPI
TcgDxeHashLogExtendEventI (
  IN      TCG_DXE_DATA              *TcgData,
  IN      UINT8                     *HashData,
  IN      UINT64                    HashDataLen,
  IN OUT  TCG_PCR_EVENT_HDR         *NewEventHdr,
  IN      UINT8                     *NewEventData
  )
{
  EFI_STATUS                        Status;

  if (HashDataLen > 0) {
    Status = TpmCommHashAll (
               HashData,
               (UINTN) HashDataLen,
               &NewEventHdr->Digest
               );
    ASSERT_EFI_ERROR (Status);
  }

  Status = TpmCommExtend (
             TcgData->TpmHandle,
             &NewEventHdr->Digest,
             NewEventHdr->PCRIndex,
             NULL
             );
  if (!EFI_ERROR (Status)) {
    Status = TcgDxeLogEventI (TcgData, NewEventHdr, NewEventData);
  }

  return Status;
}

/**
  This service abstracts the capability to do a hash operation on a data buffer,
  extend a specific TPM PCR with the hash result, and add an entry to the Event Log

  @param[in]      This               Indicates the calling context
  @param[in]      HashData           Physical address of the start of the data buffer 
                                     to be hashed, extended, and logged.
  @param[in]      HashDataLen        The length, in bytes, of the buffer referenced by HashData
  @param[in]      AlgorithmId        Identification of the Algorithm to use for the hashing operation
  @param[in, out] TCGLogData         The physical address of the start of the data 
                                     buffer containing the TCG_PCR_EVENT data structure.
  @param[in, out] EventNumber        The event number of the event just logged.
  @param[out]     EventLogLastEntry  Physical address of the first byte of the entry 
                                     just placed in the Event Log. If the Event Log was 
                                     empty when this function was called then this physical 
                                     address will be the same as the physical address of 
                                     the start of the Event Log.

  @retval EFI_SUCCESS                Operation completed successfully.
  @retval EFI_UNSUPPORTED            AlgorithmId != TPM_ALG_SHA.
  @retval EFI_UNSUPPORTED            Current TPL >= EFI_TPL_CALLBACK.
  @retval EFI_DEVICE_ERROR           The command was unsuccessful.
  
**/
EFI_STATUS
EFIAPI
TcgDxeHashLogExtendEvent (
  IN      EFI_TCG_PROTOCOL          *This,
  IN      EFI_PHYSICAL_ADDRESS      HashData,
  IN      UINT64                    HashDataLen,
  IN      TPM_ALGORITHM_ID          AlgorithmId,
  IN OUT  TCG_PCR_EVENT             *TCGLogData,
  IN OUT  UINT32                    *EventNumber,
     OUT  EFI_PHYSICAL_ADDRESS      *EventLogLastEntry
  )
{
  TCG_DXE_DATA  *TcgData;

  TcgData = TCG_DXE_DATA_FROM_THIS (This);
  
  if (TcgData->BsCap.TPMDeactivatedFlag) {
    return EFI_DEVICE_ERROR;
  }
    
  if (AlgorithmId != TPM_ALG_SHA) {
    return EFI_UNSUPPORTED;
  }

  return TcgDxeHashLogExtendEventI (
           TcgData,
           (UINT8 *) (UINTN) HashData,
           HashDataLen,
           (TCG_PCR_EVENT_HDR*)TCGLogData,
           TCGLogData->Event
           );
}

TCG_DXE_DATA                 mTcgDxeData = {
  {
    TcgDxeStatusCheck,
    TcgDxeHashAll,
    TcgDxeLogEvent,
    TcgDxePassThroughToTpm,
    TcgDxeHashLogExtendEvent
  },
  {
    sizeof (mTcgDxeData.BsCap),
    { 1, 2, 0, 0 },
    { 1, 2, 0, 0 },
    1,
    TRUE,
    FALSE
  },
  &mTcgClientAcpiTemplate,
  &mTcgServerAcpiTemplate,
  0,
  NULL,
  NULL
};

/**
  Initialize the Event Log and log events passed from the PEI phase.

  @retval EFI_SUCCESS           Operation completed successfully.
  @retval EFI_OUT_OF_RESOURCES  Out of memory.

**/
EFI_STATUS
EFIAPI
SetupEventLog (
  VOID
  )
{
  EFI_STATUS            Status;
  TCG_PCR_EVENT         *TcgEvent;
  EFI_PEI_HOB_POINTERS  GuidHob;
  EFI_PHYSICAL_ADDRESS  Lasa;
  
  if (PcdGet8 (PcdTpmPlatformClass) == TCG_PLATFORM_TYPE_CLIENT) {
    Lasa = mTcgClientAcpiTemplate.Lasa;
  
    Status = gBS->AllocatePages (
                    AllocateMaxAddress,
                    EfiACPIMemoryNVS,
                    EFI_SIZE_TO_PAGES (EFI_TCG_LOG_AREA_SIZE),
                    &Lasa
                    );
    if (EFI_ERROR (Status)) {
      return Status;
    }
    mTcgClientAcpiTemplate.Lasa = Lasa;
    //
    // To initialize them as 0xFF is recommended 
    // because the OS can know the last entry for that.
    //
    SetMem ((VOID *)(UINTN)mTcgClientAcpiTemplate.Lasa, EFI_TCG_LOG_AREA_SIZE, 0xFF);
    mTcgClientAcpiTemplate.Laml = EFI_TCG_LOG_AREA_SIZE;
  
  } else {
    Lasa = mTcgServerAcpiTemplate.Lasa;
  
    Status = gBS->AllocatePages (
                    AllocateMaxAddress,
                    EfiACPIMemoryNVS,
                    EFI_SIZE_TO_PAGES (EFI_TCG_LOG_AREA_SIZE),
                    &Lasa
                    );
    if (EFI_ERROR (Status)) {
      return Status;
    }
    mTcgServerAcpiTemplate.Lasa = Lasa;
    //
    // To initialize them as 0xFF is recommended 
    // because the OS can know the last entry for that.
    //
    SetMem ((VOID *)(UINTN)mTcgServerAcpiTemplate.Lasa, EFI_TCG_LOG_AREA_SIZE, 0xFF);
    mTcgServerAcpiTemplate.Laml = EFI_TCG_LOG_AREA_SIZE;
  }

  GuidHob.Raw = GetHobList ();
  while (!EFI_ERROR (Status) && 
         (GuidHob.Raw = GetNextGuidHob (&gTcgEventEntryHobGuid, GuidHob.Raw)) != NULL) {
    TcgEvent    = GET_GUID_HOB_DATA (GuidHob.Guid);
    GuidHob.Raw = GET_NEXT_HOB (GuidHob);
    Status = TcgDxeLogEventI (
               &mTcgDxeData,
               (TCG_PCR_EVENT_HDR*)TcgEvent,
               TcgEvent->Event
               );
  }

  return Status;
}

/**
  Measure and log an action string, and extend the measurement result into PCR[5].

  @param[in] String           A specific string that indicates an Action event.  
  
  @retval EFI_SUCCESS         Operation completed successfully.
  @retval EFI_DEVICE_ERROR    The operation was unsuccessful.

**/
EFI_STATUS
EFIAPI
TcgMeasureAction (
  IN      CHAR8                     *String
  )
{
  TCG_PCR_EVENT_HDR                 TcgEvent;

  TcgEvent.PCRIndex  = 5;
  TcgEvent.EventType = EV_EFI_ACTION;
  TcgEvent.EventSize = (UINT32)AsciiStrLen (String);
  return TcgDxeHashLogExtendEventI (
           &mTcgDxeData,
           (UINT8*)String,
           TcgEvent.EventSize,
           &TcgEvent,
           (UINT8 *) String
           );
}

/**
  Measure and log EFI handoff tables, and extend the measurement result into PCR[1].

  @retval EFI_SUCCESS         Operation completed successfully.
  @retval EFI_DEVICE_ERROR    The operation was unsuccessful.

**/
EFI_STATUS
EFIAPI
MeasureHandoffTables (
  VOID
  )
{
  EFI_STATUS                        Status;
  SMBIOS_TABLE_ENTRY_POINT          *SmbiosTable;
  TCG_PCR_EVENT_HDR                 TcgEvent;
  EFI_HANDOFF_TABLE_POINTERS        HandoffTables;

  Status = EfiGetSystemConfigurationTable (
             &gEfiSmbiosTableGuid,
             (VOID **) &SmbiosTable
             );

  if (!EFI_ERROR (Status)) {
    ASSERT (SmbiosTable != NULL);

    TcgEvent.PCRIndex  = 1;
    TcgEvent.EventType = EV_EFI_HANDOFF_TABLES;
    TcgEvent.EventSize = sizeof (HandoffTables);

    HandoffTables.NumberOfTables = 1;
    HandoffTables.TableEntry[0].VendorGuid  = gEfiSmbiosTableGuid;
    HandoffTables.TableEntry[0].VendorTable = SmbiosTable;

    DEBUG ((DEBUG_INFO, "The Smbios Table starts at: 0x%x\n", SmbiosTable->TableAddress));
    DEBUG ((DEBUG_INFO, "The Smbios Table size: 0x%x\n", SmbiosTable->TableLength));

    Status = TcgDxeHashLogExtendEventI (
               &mTcgDxeData,
               (UINT8*)(UINTN)SmbiosTable->TableAddress,
               SmbiosTable->TableLength,
               &TcgEvent,
               (UINT8*)&HandoffTables
               );
  }

  return Status;
}

/**
  Measure and log Separator event, and extend the measurement result into a specific PCR.

  @param[in] PCRIndex         PCR index.  

  @retval EFI_SUCCESS         Operation completed successfully.
  @retval EFI_DEVICE_ERROR    The operation was unsuccessful.

**/
EFI_STATUS
EFIAPI
MeasureSeparatorEvent (
  IN      TPM_PCRINDEX              PCRIndex
  )
{
  TCG_PCR_EVENT_HDR                 TcgEvent;
  UINT32                            EventData;

  EventData = 0;
  TcgEvent.PCRIndex  = PCRIndex;
  TcgEvent.EventType = EV_SEPARATOR;
  TcgEvent.EventSize = (UINT32)sizeof (EventData);
  return TcgDxeHashLogExtendEventI (
           &mTcgDxeData,
           (UINT8 *)&EventData,
           sizeof (EventData),
           &TcgEvent,
           (UINT8 *)&EventData
           );
}

/**
  Read an EFI Variable.

  This function allocates a buffer to return the contents of the variable. The caller is
  responsible for freeing the buffer.

  @param[in]  VarName     A Null-terminated string that is the name of the vendor's variable.
  @param[in]  VendorGuid  A unique identifier for the vendor.
  @param[out] VarSize     The size of the variable data.  

  @return A pointer to the buffer to return the contents of the variable.Otherwise NULL.

**/
VOID *
EFIAPI
ReadVariable (
  IN      CHAR16                    *VarName,
  IN      EFI_GUID                  *VendorGuid,
  OUT     UINTN                     *VarSize
  )
{
  EFI_STATUS                        Status;
  VOID                              *VarData;

  *VarSize = 0;
  Status = gRT->GetVariable (
                  VarName,
                  VendorGuid,
                  NULL,
                  VarSize,
                  NULL
                  );
  if (Status != EFI_BUFFER_TOO_SMALL) {
    return NULL;
  }

  VarData = AllocatePool (*VarSize);
  if (VarData != NULL) {
    Status = gRT->GetVariable (
                    VarName,
                    VendorGuid,
                    NULL,
                    VarSize,
                    VarData
                    );
    if (EFI_ERROR (Status)) {
      FreePool (VarData);
      VarData = NULL;
      *VarSize = 0;
    }
  }
  return VarData;
}

/**
  Measure and log an EFI variable, and extend the measurement result into a specific PCR.

  @param[in]  PCRIndex          PCR Index.  
  @param[in]  EventType         Event type.  
  @param[in]  VarName           A Null-terminated string that is the name of the vendor's variable.
  @param[in]  VendorGuid        A unique identifier for the vendor.
  @param[in]  VarData           The content of the variable data.  
  @param[in]  VarSize           The size of the variable data.  
 
  @retval EFI_SUCCESS           Operation completed successfully.
  @retval EFI_OUT_OF_RESOURCES  Out of memory.
  @retval EFI_DEVICE_ERROR      The operation was unsuccessful.

**/
EFI_STATUS
EFIAPI
MeasureVariable (
  IN      TPM_PCRINDEX              PCRIndex,
  IN      TCG_EVENTTYPE             EventType,
  IN      CHAR16                    *VarName,
  IN      EFI_GUID                  *VendorGuid,
  IN      VOID                      *VarData,
  IN      UINTN                     VarSize
  )
{
  EFI_STATUS                        Status;
  TCG_PCR_EVENT_HDR                 TcgEvent;
  UINTN                             VarNameLength;
  EFI_VARIABLE_DATA                 *VarLog;

  VarNameLength      = StrLen (VarName);
  TcgEvent.PCRIndex  = PCRIndex;
  TcgEvent.EventType = EventType;
  TcgEvent.EventSize = (UINT32)(sizeof (*VarLog) + VarNameLength * sizeof (*VarName) + VarSize
                        - sizeof (VarLog->UnicodeName) - sizeof (VarLog->VariableData));

  VarLog = (EFI_VARIABLE_DATA*)AllocatePool (TcgEvent.EventSize);
  if (VarLog == NULL) {
    return EFI_OUT_OF_RESOURCES;
  }

  VarLog->VariableName       = *VendorGuid;
  VarLog->UnicodeNameLength  = VarNameLength;
  VarLog->VariableDataLength = VarSize;
  CopyMem (
     VarLog->UnicodeName,
     VarName,
     VarNameLength * sizeof (*VarName)
     );
  CopyMem (
     (CHAR16 *)VarLog->UnicodeName + VarNameLength,
     VarData,
     VarSize
     );

  Status = TcgDxeHashLogExtendEventI (
             &mTcgDxeData,
             (UINT8*)VarData,
             VarSize,
             &TcgEvent,
             (UINT8*)VarLog
             );
  FreePool (VarLog);
  return Status;
}

/**
  Read then Measure and log an EFI boot variable, and extend the measurement result into PCR[5].

  @param[in]   VarName          A Null-terminated string that is the name of the vendor's variable.
  @param[in]   VendorGuid       A unique identifier for the vendor.
  @param[out]  VarSize          The size of the variable data.  
  @param[out]  VarData          Pointer to the content of the variable.  
 
  @retval EFI_SUCCESS           Operation completed successfully.
  @retval EFI_OUT_OF_RESOURCES  Out of memory.
  @retval EFI_DEVICE_ERROR      The operation was unsuccessful.

**/
EFI_STATUS
EFIAPI
ReadAndMeasureBootVariable (
  IN      CHAR16                    *VarName,
  IN      EFI_GUID                  *VendorGuid,
  OUT     UINTN                     *VarSize,
  OUT     VOID                      **VarData
  )
{
  EFI_STATUS                        Status;

  *VarData = ReadVariable (VarName, VendorGuid, VarSize);
  if (*VarData == NULL) {
    return EFI_NOT_FOUND;
  }

  Status = MeasureVariable (
             5,
             EV_EFI_VARIABLE_BOOT,
             VarName,
             VendorGuid,
             *VarData,
             *VarSize
             );
  return Status;
}

/**
  Measure and log all EFI boot variables, and extend the measurement result into a specific PCR.

  The EFI boot variables are BootOrder and Boot#### variables.

  @retval EFI_SUCCESS           Operation completed successfully.
  @retval EFI_OUT_OF_RESOURCES  Out of memory.
  @retval EFI_DEVICE_ERROR      The operation was unsuccessful.

**/
EFI_STATUS
EFIAPI
MeasureAllBootVariables (
  VOID
  )
{
  EFI_STATUS                        Status;
  UINT16                            *BootOrder;
  UINTN                             BootCount;
  UINTN                             Index;
  VOID                              *BootVarData;
  UINTN                             Size;

  Status = ReadAndMeasureBootVariable (
             mBootVarName,
             &gEfiGlobalVariableGuid,
             &BootCount,
             (VOID **) &BootOrder
             );
  if (Status == EFI_NOT_FOUND) {
    return EFI_SUCCESS;
  }
  ASSERT (BootOrder != NULL);

  if (EFI_ERROR (Status)) {
    FreePool (BootOrder);
    return Status;
  }

  BootCount /= sizeof (*BootOrder);
  for (Index = 0; Index < BootCount; Index++) {
    UnicodeSPrint (mBootVarName, sizeof (mBootVarName), L"Boot%04x", BootOrder[Index]);
    Status = ReadAndMeasureBootVariable (
               mBootVarName,
               &gEfiGlobalVariableGuid,
               &Size,
               &BootVarData
               );
    if (!EFI_ERROR (Status)) {
      FreePool (BootVarData);
    }
  }

  FreePool (BootOrder);
  return EFI_SUCCESS;
}

/**
  Ready to Boot Event notification handler.

  Sequence of OS boot events is measured in this event notification handler.

  @param[in]  Event     Event whose notification function is being invoked
  @param[in]  Context   Pointer to the notification function's context

**/
VOID
EFIAPI
OnReadyToBoot (
  IN      EFI_EVENT                 Event,
  IN      VOID                      *Context
  )
{
  EFI_STATUS                        Status;
  TPM_PCRINDEX                      PcrIndex;

  if (mBootAttempts == 0) {

    //
    // Measure handoff tables.
    //
    Status = MeasureHandoffTables ();
    if (EFI_ERROR (Status)) {
      DEBUG ((EFI_D_ERROR, "HOBs not Measured. Error!\n"));
    }

    //
    // Measure BootOrder & Boot#### variables.
    //
    Status = MeasureAllBootVariables ();
    if (EFI_ERROR (Status)) {
      DEBUG ((EFI_D_ERROR, "Boot Variables not Measured. Error!\n"));
    }

    //
    // 1. This is the first boot attempt.
    //
    Status = TcgMeasureAction (
               EFI_CALLING_EFI_APPLICATION
               );
    ASSERT_EFI_ERROR (Status);

    //
    // 2. Draw a line between pre-boot env and entering post-boot env.
    //
    for (PcrIndex = 0; PcrIndex < 8; PcrIndex++) {
      Status = MeasureSeparatorEvent (PcrIndex);
      ASSERT_EFI_ERROR (Status);
    }

    //
    // 3. Measure GPT. It would be done in SAP driver.
    //

    //
    // 4. Measure PE/COFF OS loader. It would be done in SAP driver.
    //

    //
    // 5. Read & Measure variable. BootOrder already measured.
    //
  } else {
    //
    // 6. Not first attempt, meaning a return from last attempt
    //
    Status = TcgMeasureAction (
               EFI_RETURNING_FROM_EFI_APPLICATOIN
               );
    ASSERT_EFI_ERROR (Status);
  }

  DEBUG ((EFI_D_INFO, "TPM TcgDxe Measure Data when ReadyToBoot\n"));
  //
  // Increase boot attempt counter.
  //
  mBootAttempts++;
}

/**
  Install TCG ACPI Table when ACPI Table Protocol is available.

  A system's firmware uses an ACPI table to identify the system's TCG capabilities 
  to the Post-Boot environment. The information in this ACPI table is not guaranteed 
  to be valid until the Host Platform transitions from pre-boot state to post-boot state.  

  @param[in]  Event     Event whose notification function is being invoked
  @param[in]  Context   Pointer to the notification function's context
**/
VOID
EFIAPI
InstallAcpiTable (
  IN EFI_EVENT                      Event,
  IN VOID*                          Context
  )
{
  UINTN                             TableKey;
  EFI_STATUS                        Status;
  EFI_ACPI_TABLE_PROTOCOL           *AcpiTable;
  UINT8                             Checksum;

  Status = gBS->LocateProtocol (&gEfiAcpiTableProtocolGuid, NULL, (VOID **)&AcpiTable);
  if (EFI_ERROR (Status)) {
    return;
  }

  if (PcdGet8 (PcdTpmPlatformClass) == TCG_PLATFORM_TYPE_CLIENT) {
 
    //
    // The ACPI table must be checksumed before calling the InstallAcpiTable() 
    // service of the ACPI table protocol to install it.
    //
    Checksum = CalculateCheckSum8 ((UINT8 *)&mTcgClientAcpiTemplate, sizeof (mTcgClientAcpiTemplate));
    mTcgClientAcpiTemplate.Header.Checksum = Checksum;

    Status = AcpiTable->InstallAcpiTable (
                            AcpiTable,
                            &mTcgClientAcpiTemplate,
                            sizeof (mTcgClientAcpiTemplate),
                            &TableKey
                            );
  } else {

    //
    // The ACPI table must be checksumed before calling the InstallAcpiTable() 
    // service of the ACPI table protocol to install it.
    //
    Checksum = CalculateCheckSum8 ((UINT8 *)&mTcgServerAcpiTemplate, sizeof (mTcgServerAcpiTemplate));
    mTcgServerAcpiTemplate.Header.Checksum = Checksum;

    Status = AcpiTable->InstallAcpiTable (
                            AcpiTable,
                            &mTcgServerAcpiTemplate,
                            sizeof (mTcgServerAcpiTemplate),
                            &TableKey
                            );
  }
  ASSERT_EFI_ERROR (Status);
}

/**
  Exit Boot Services Event notification handler.

  Measure invocation and success of ExitBootServices.

  @param[in]  Event     Event whose notification function is being invoked
  @param[in]  Context   Pointer to the notification function's context

**/
VOID
EFIAPI
OnExitBootServices (
  IN      EFI_EVENT                 Event,
  IN      VOID                      *Context
  )
{
  EFI_STATUS    Status;

  //
  // Measure invocation of ExitBootServices,
  //
  Status = TcgMeasureAction (
             EFI_EXIT_BOOT_SERVICES_INVOCATION
             );
  ASSERT_EFI_ERROR (Status);

  //
  // Measure success of ExitBootServices
  //
  Status = TcgMeasureAction (
             EFI_EXIT_BOOT_SERVICES_SUCCEEDED
             );
  ASSERT_EFI_ERROR (Status);
}

/**
  Get TPM Deactivated state.

  @param[out] TPMDeactivatedFlag   Returns TPM Deactivated state.  

  @retval EFI_SUCCESS              Operation completed successfully.
  @retval EFI_DEVICE_ERROR         The operation was unsuccessful.

**/
EFI_STATUS
GetTpmStatus (
     OUT  BOOLEAN                   *TPMDeactivatedFlag
  )
{
  EFI_STATUS                        Status;
  TPM_STCLEAR_FLAGS                 VFlags;

  Status = TpmCommGetFlags (
             mTcgDxeData.TpmHandle,
             TPM_CAP_FLAG_VOLATILE,
             &VFlags,
             sizeof (VFlags)
             );
  if (!EFI_ERROR (Status)) {
    *TPMDeactivatedFlag = VFlags.deactivated;
  }

  return Status;
}

/**
  The driver's entry point.

  It publishes EFI TCG Protocol.

  @param[in] ImageHandle  The firmware allocated handle for the EFI image.  
  @param[in] SystemTable  A pointer to the EFI System Table.
  
  @retval EFI_SUCCESS     The entry point is executed successfully.
  @retval other           Some error occurs when executing this entry point.

**/
EFI_STATUS
EFIAPI
DriverEntry (
  IN    EFI_HANDLE                  ImageHandle,
  IN    EFI_SYSTEM_TABLE            *SystemTable
  )
{
  EFI_STATUS                        Status;
  EFI_EVENT                         Event;
  VOID                              *Registration;

  mTcgDxeData.TpmHandle = (TIS_TPM_HANDLE)(UINTN)TPM_BASE_ADDRESS;
  Status = TisPcRequestUseTpm (mTcgDxeData.TpmHandle);
  if (EFI_ERROR (Status)) {
    DEBUG ((EFI_D_ERROR, "TPM not detected!\n"));
    return Status;
  }

  Status = GetTpmStatus (&mTcgDxeData.BsCap.TPMDeactivatedFlag);
  if (EFI_ERROR (Status)) {
    DEBUG ((
      EFI_D_ERROR,
      "Line %d in file " __FILE__ ":\n    "
      "DriverEntry: TPM not working properly\n",
      __LINE__
      ));
    return Status;
  }

  Status = gBS->InstallProtocolInterface (
                  &ImageHandle,
                  &gEfiTcgProtocolGuid,
                  EFI_NATIVE_INTERFACE,
                  &mTcgDxeData.TcgProtocol
                  );
  //
  // Install ACPI Table
  //
  EfiCreateProtocolNotifyEvent (&gEfiAcpiTableProtocolGuid, TPL_CALLBACK, InstallAcpiTable, NULL, &Registration);
    
  if (!EFI_ERROR (Status) && !mTcgDxeData.BsCap.TPMDeactivatedFlag) {
    //
    // Setup the log area and copy event log from hob list to it
    //
    Status = SetupEventLog ();
    ASSERT_EFI_ERROR (Status);

    //
    // Measure handoff tables, Boot#### variables etc.
    //
    Status = EfiCreateEventReadyToBootEx (
               TPL_CALLBACK,
               OnReadyToBoot,
               NULL,
               &Event
               );

    Status = gBS->CreateEventEx (
                    EVT_NOTIFY_SIGNAL,
                    TPL_NOTIFY,
                    OnExitBootServices,
                    NULL,
                    &gEfiEventExitBootServicesGuid,
                    &Event
                    );
  }

  return Status;
}