1 /** @file
2 Implement authentication services for the authenticated variables.
3
4 Caution: This module requires additional review when modified.
5 This driver will have external input - variable data. It may be input in SMM mode.
6 This external input must be validated carefully to avoid security issue like
7 buffer overflow, integer overflow.
8 Variable attribute should also be checked to avoid authentication bypass.
9 The whole SMM authentication variable design relies on the integrity of flash part and SMM.
10 which is assumed to be protected by platform. All variable code and metadata in flash/SMM Memory
11 may not be modified without authorization. If platform fails to protect these resources,
12 the authentication service provided in this driver will be broken, and the behavior is undefined.
13
14 ProcessVarWithPk(), ProcessVarWithKek() and ProcessVariable() are the function to do
15 variable authentication.
16
17 VerifyTimeBasedPayloadAndUpdate() and VerifyCounterBasedPayload() are sub function to do verification.
18 They will do basic validation for authentication data structure, then call crypto library
19 to verify the signature.
20
21 Copyright (c) 2009 - 2016, Intel Corporation. All rights reserved.<BR>
22 This program and the accompanying materials
23 are licensed and made available under the terms and conditions of the BSD License
24 which accompanies this distribution. The full text of the license may be found at
25 http://opensource.org/licenses/bsd-license.php
26
27 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
28 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
29
30 **/
31
32 #include "AuthServiceInternal.h"
33
34 //
35 // Public Exponent of RSA Key.
36 //
37 CONST UINT8 mRsaE[] = { 0x01, 0x00, 0x01 };
38
39 //
40 // Requirement for different signature type which have been defined in UEFI spec.
41 // These data are used to perform SignatureList format check while setting PK/KEK variable.
42 //
43 EFI_SIGNATURE_ITEM mSupportSigItem[] = {
44 //{SigType, SigHeaderSize, SigDataSize }
45 {EFI_CERT_SHA256_GUID, 0, 32 },
46 {EFI_CERT_RSA2048_GUID, 0, 256 },
47 {EFI_CERT_RSA2048_SHA256_GUID, 0, 256 },
48 {EFI_CERT_SHA1_GUID, 0, 20 },
49 {EFI_CERT_RSA2048_SHA1_GUID, 0, 256 },
50 {EFI_CERT_X509_GUID, 0, ((UINT32) ~0)},
51 {EFI_CERT_SHA224_GUID, 0, 28 },
52 {EFI_CERT_SHA384_GUID, 0, 48 },
53 {EFI_CERT_SHA512_GUID, 0, 64 },
54 {EFI_CERT_X509_SHA256_GUID, 0, 48 },
55 {EFI_CERT_X509_SHA384_GUID, 0, 64 },
56 {EFI_CERT_X509_SHA512_GUID, 0, 80 }
57 };
58
59 /**
60 Finds variable in storage blocks of volatile and non-volatile storage areas.
61
62 This code finds variable in storage blocks of volatile and non-volatile storage areas.
63 If VariableName is an empty string, then we just return the first
64 qualified variable without comparing VariableName and VendorGuid.
65
66 @param[in] VariableName Name of the variable to be found.
67 @param[in] VendorGuid Variable vendor GUID to be found.
68 @param[out] Data Pointer to data address.
69 @param[out] DataSize Pointer to data size.
70
71 @retval EFI_INVALID_PARAMETER If VariableName is not an empty string,
72 while VendorGuid is NULL.
73 @retval EFI_SUCCESS Variable successfully found.
74 @retval EFI_NOT_FOUND Variable not found
75
76 **/
77 EFI_STATUS
AuthServiceInternalFindVariable(IN CHAR16 * VariableName,IN EFI_GUID * VendorGuid,OUT VOID ** Data,OUT UINTN * DataSize)78 AuthServiceInternalFindVariable (
79 IN CHAR16 *VariableName,
80 IN EFI_GUID *VendorGuid,
81 OUT VOID **Data,
82 OUT UINTN *DataSize
83 )
84 {
85 EFI_STATUS Status;
86 AUTH_VARIABLE_INFO AuthVariableInfo;
87
88 ZeroMem (&AuthVariableInfo, sizeof (AuthVariableInfo));
89 Status = mAuthVarLibContextIn->FindVariable (
90 VariableName,
91 VendorGuid,
92 &AuthVariableInfo
93 );
94 *Data = AuthVariableInfo.Data;
95 *DataSize = AuthVariableInfo.DataSize;
96 return Status;
97 }
98
99 /**
100 Update the variable region with Variable information.
101
102 @param[in] VariableName Name of variable.
103 @param[in] VendorGuid Guid of variable.
104 @param[in] Data Data pointer.
105 @param[in] DataSize Size of Data.
106 @param[in] Attributes Attribute value of the variable.
107
108 @retval EFI_SUCCESS The update operation is success.
109 @retval EFI_INVALID_PARAMETER Invalid parameter.
110 @retval EFI_WRITE_PROTECTED Variable is write-protected.
111 @retval EFI_OUT_OF_RESOURCES There is not enough resource.
112
113 **/
114 EFI_STATUS
AuthServiceInternalUpdateVariable(IN CHAR16 * VariableName,IN EFI_GUID * VendorGuid,IN VOID * Data,IN UINTN DataSize,IN UINT32 Attributes)115 AuthServiceInternalUpdateVariable (
116 IN CHAR16 *VariableName,
117 IN EFI_GUID *VendorGuid,
118 IN VOID *Data,
119 IN UINTN DataSize,
120 IN UINT32 Attributes
121 )
122 {
123 AUTH_VARIABLE_INFO AuthVariableInfo;
124
125 ZeroMem (&AuthVariableInfo, sizeof (AuthVariableInfo));
126 AuthVariableInfo.VariableName = VariableName;
127 AuthVariableInfo.VendorGuid = VendorGuid;
128 AuthVariableInfo.Data = Data;
129 AuthVariableInfo.DataSize = DataSize;
130 AuthVariableInfo.Attributes = Attributes;
131
132 return mAuthVarLibContextIn->UpdateVariable (
133 &AuthVariableInfo
134 );
135 }
136
137 /**
138 Update the variable region with Variable information.
139
140 @param[in] VariableName Name of variable.
141 @param[in] VendorGuid Guid of variable.
142 @param[in] Data Data pointer.
143 @param[in] DataSize Size of Data.
144 @param[in] Attributes Attribute value of the variable.
145 @param[in] KeyIndex Index of associated public key.
146 @param[in] MonotonicCount Value of associated monotonic count.
147
148 @retval EFI_SUCCESS The update operation is success.
149 @retval EFI_INVALID_PARAMETER Invalid parameter.
150 @retval EFI_WRITE_PROTECTED Variable is write-protected.
151 @retval EFI_OUT_OF_RESOURCES There is not enough resource.
152
153 **/
154 EFI_STATUS
AuthServiceInternalUpdateVariableWithMonotonicCount(IN CHAR16 * VariableName,IN EFI_GUID * VendorGuid,IN VOID * Data,IN UINTN DataSize,IN UINT32 Attributes,IN UINT32 KeyIndex,IN UINT64 MonotonicCount)155 AuthServiceInternalUpdateVariableWithMonotonicCount (
156 IN CHAR16 *VariableName,
157 IN EFI_GUID *VendorGuid,
158 IN VOID *Data,
159 IN UINTN DataSize,
160 IN UINT32 Attributes,
161 IN UINT32 KeyIndex,
162 IN UINT64 MonotonicCount
163 )
164 {
165 AUTH_VARIABLE_INFO AuthVariableInfo;
166
167 ZeroMem (&AuthVariableInfo, sizeof (AuthVariableInfo));
168 AuthVariableInfo.VariableName = VariableName;
169 AuthVariableInfo.VendorGuid = VendorGuid;
170 AuthVariableInfo.Data = Data;
171 AuthVariableInfo.DataSize = DataSize;
172 AuthVariableInfo.Attributes = Attributes;
173 AuthVariableInfo.PubKeyIndex = KeyIndex;
174 AuthVariableInfo.MonotonicCount = MonotonicCount;
175
176 return mAuthVarLibContextIn->UpdateVariable (
177 &AuthVariableInfo
178 );
179 }
180
181 /**
182 Update the variable region with Variable information.
183
184 @param[in] VariableName Name of variable.
185 @param[in] VendorGuid Guid of variable.
186 @param[in] Data Data pointer.
187 @param[in] DataSize Size of Data.
188 @param[in] Attributes Attribute value of the variable.
189 @param[in] TimeStamp Value of associated TimeStamp.
190
191 @retval EFI_SUCCESS The update operation is success.
192 @retval EFI_INVALID_PARAMETER Invalid parameter.
193 @retval EFI_WRITE_PROTECTED Variable is write-protected.
194 @retval EFI_OUT_OF_RESOURCES There is not enough resource.
195
196 **/
197 EFI_STATUS
AuthServiceInternalUpdateVariableWithTimeStamp(IN CHAR16 * VariableName,IN EFI_GUID * VendorGuid,IN VOID * Data,IN UINTN DataSize,IN UINT32 Attributes,IN EFI_TIME * TimeStamp)198 AuthServiceInternalUpdateVariableWithTimeStamp (
199 IN CHAR16 *VariableName,
200 IN EFI_GUID *VendorGuid,
201 IN VOID *Data,
202 IN UINTN DataSize,
203 IN UINT32 Attributes,
204 IN EFI_TIME *TimeStamp
205 )
206 {
207 EFI_STATUS FindStatus;
208 VOID *OrgData;
209 UINTN OrgDataSize;
210 AUTH_VARIABLE_INFO AuthVariableInfo;
211
212 FindStatus = AuthServiceInternalFindVariable (
213 VariableName,
214 VendorGuid,
215 &OrgData,
216 &OrgDataSize
217 );
218
219 //
220 // EFI_VARIABLE_APPEND_WRITE attribute only effects for existing variable
221 //
222 if (!EFI_ERROR (FindStatus) && ((Attributes & EFI_VARIABLE_APPEND_WRITE) != 0)) {
223 if ((CompareGuid (VendorGuid, &gEfiImageSecurityDatabaseGuid) &&
224 ((StrCmp (VariableName, EFI_IMAGE_SECURITY_DATABASE) == 0) || (StrCmp (VariableName, EFI_IMAGE_SECURITY_DATABASE1) == 0) ||
225 (StrCmp (VariableName, EFI_IMAGE_SECURITY_DATABASE2) == 0))) ||
226 (CompareGuid (VendorGuid, &gEfiGlobalVariableGuid) && (StrCmp (VariableName, EFI_KEY_EXCHANGE_KEY_NAME) == 0))) {
227 //
228 // For variables with formatted as EFI_SIGNATURE_LIST, the driver shall not perform an append of
229 // EFI_SIGNATURE_DATA values that are already part of the existing variable value.
230 //
231 FilterSignatureList (
232 OrgData,
233 OrgDataSize,
234 Data,
235 &DataSize
236 );
237 }
238 }
239
240 ZeroMem (&AuthVariableInfo, sizeof (AuthVariableInfo));
241 AuthVariableInfo.VariableName = VariableName;
242 AuthVariableInfo.VendorGuid = VendorGuid;
243 AuthVariableInfo.Data = Data;
244 AuthVariableInfo.DataSize = DataSize;
245 AuthVariableInfo.Attributes = Attributes;
246 AuthVariableInfo.TimeStamp = TimeStamp;
247 return mAuthVarLibContextIn->UpdateVariable (
248 &AuthVariableInfo
249 );
250 }
251
252 /**
253 Determine whether this operation needs a physical present user.
254
255 @param[in] VariableName Name of the Variable.
256 @param[in] VendorGuid GUID of the Variable.
257
258 @retval TRUE This variable is protected, only a physical present user could set this variable.
259 @retval FALSE This variable is not protected.
260
261 **/
262 BOOLEAN
NeedPhysicallyPresent(IN CHAR16 * VariableName,IN EFI_GUID * VendorGuid)263 NeedPhysicallyPresent(
264 IN CHAR16 *VariableName,
265 IN EFI_GUID *VendorGuid
266 )
267 {
268 if ((CompareGuid (VendorGuid, &gEfiSecureBootEnableDisableGuid) && (StrCmp (VariableName, EFI_SECURE_BOOT_ENABLE_NAME) == 0))
269 || (CompareGuid (VendorGuid, &gEfiCustomModeEnableGuid) && (StrCmp (VariableName, EFI_CUSTOM_MODE_NAME) == 0))) {
270 return TRUE;
271 }
272
273 return FALSE;
274 }
275
276 /**
277 Determine whether the platform is operating in Custom Secure Boot mode.
278
279 @retval TRUE The platform is operating in Custom mode.
280 @retval FALSE The platform is operating in Standard mode.
281
282 **/
283 BOOLEAN
InCustomMode(VOID)284 InCustomMode (
285 VOID
286 )
287 {
288 EFI_STATUS Status;
289 VOID *Data;
290 UINTN DataSize;
291
292 Status = AuthServiceInternalFindVariable (EFI_CUSTOM_MODE_NAME, &gEfiCustomModeEnableGuid, &Data, &DataSize);
293 if (!EFI_ERROR (Status) && (*(UINT8 *) Data == CUSTOM_SECURE_BOOT_MODE)) {
294 return TRUE;
295 }
296
297 return FALSE;
298 }
299
300 /**
301 Get available public key index.
302
303 @param[in] PubKey Pointer to Public Key data.
304
305 @return Public key index, 0 if no any public key index available.
306
307 **/
308 UINT32
GetAvailableKeyIndex(IN UINT8 * PubKey)309 GetAvailableKeyIndex (
310 IN UINT8 *PubKey
311 )
312 {
313 EFI_STATUS Status;
314 UINT8 *Data;
315 UINTN DataSize;
316 UINT8 *Ptr;
317 UINT32 Index;
318 BOOLEAN IsFound;
319 EFI_GUID VendorGuid;
320 CHAR16 Name[1];
321 AUTH_VARIABLE_INFO AuthVariableInfo;
322 UINT32 KeyIndex;
323
324 Status = AuthServiceInternalFindVariable (
325 AUTHVAR_KEYDB_NAME,
326 &gEfiAuthenticatedVariableGuid,
327 (VOID **) &Data,
328 &DataSize
329 );
330 if (EFI_ERROR (Status)) {
331 DEBUG ((EFI_D_ERROR, "Get public key database variable failure, Status = %r\n", Status));
332 return 0;
333 }
334
335 if (mPubKeyNumber == mMaxKeyNumber) {
336 Name[0] = 0;
337 AuthVariableInfo.VariableName = Name;
338 ZeroMem (&VendorGuid, sizeof (VendorGuid));
339 AuthVariableInfo.VendorGuid = &VendorGuid;
340 mPubKeyNumber = 0;
341 //
342 // Collect valid key data.
343 //
344 do {
345 Status = mAuthVarLibContextIn->FindNextVariable (AuthVariableInfo.VariableName, AuthVariableInfo.VendorGuid, &AuthVariableInfo);
346 if (!EFI_ERROR (Status)) {
347 if (AuthVariableInfo.PubKeyIndex != 0) {
348 for (Ptr = Data; Ptr < (Data + DataSize); Ptr += sizeof (AUTHVAR_KEY_DB_DATA)) {
349 if (ReadUnaligned32 (&(((AUTHVAR_KEY_DB_DATA *) Ptr)->KeyIndex)) == AuthVariableInfo.PubKeyIndex) {
350 //
351 // Check if the key data has been collected.
352 //
353 for (Index = 0; Index < mPubKeyNumber; Index++) {
354 if (ReadUnaligned32 (&(((AUTHVAR_KEY_DB_DATA *) mPubKeyStore + Index)->KeyIndex)) == AuthVariableInfo.PubKeyIndex) {
355 break;
356 }
357 }
358 if (Index == mPubKeyNumber) {
359 //
360 // New key data.
361 //
362 CopyMem ((AUTHVAR_KEY_DB_DATA *) mPubKeyStore + mPubKeyNumber, Ptr, sizeof (AUTHVAR_KEY_DB_DATA));
363 mPubKeyNumber++;
364 }
365 break;
366 }
367 }
368 }
369 }
370 } while (Status != EFI_NOT_FOUND);
371
372 //
373 // No available space to add new public key.
374 //
375 if (mPubKeyNumber == mMaxKeyNumber) {
376 return 0;
377 }
378 }
379
380 //
381 // Find available public key index.
382 //
383 for (KeyIndex = 1; KeyIndex <= mMaxKeyNumber; KeyIndex++) {
384 IsFound = FALSE;
385 for (Ptr = mPubKeyStore; Ptr < (mPubKeyStore + mPubKeyNumber * sizeof (AUTHVAR_KEY_DB_DATA)); Ptr += sizeof (AUTHVAR_KEY_DB_DATA)) {
386 if (ReadUnaligned32 (&(((AUTHVAR_KEY_DB_DATA *) Ptr)->KeyIndex)) == KeyIndex) {
387 IsFound = TRUE;
388 break;
389 }
390 }
391 if (!IsFound) {
392 break;
393 }
394 }
395
396 return KeyIndex;
397 }
398
399 /**
400 Add public key in store and return its index.
401
402 @param[in] PubKey Input pointer to Public Key data.
403 @param[in] VariableDataEntry The variable data entry.
404
405 @return Index of new added public key.
406
407 **/
408 UINT32
AddPubKeyInStore(IN UINT8 * PubKey,IN VARIABLE_ENTRY_CONSISTENCY * VariableDataEntry)409 AddPubKeyInStore (
410 IN UINT8 *PubKey,
411 IN VARIABLE_ENTRY_CONSISTENCY *VariableDataEntry
412 )
413 {
414 EFI_STATUS Status;
415 UINT32 Index;
416 VARIABLE_ENTRY_CONSISTENCY PublicKeyEntry;
417 UINT32 Attributes;
418 UINT32 KeyIndex;
419
420 if (PubKey == NULL) {
421 return 0;
422 }
423
424 //
425 // Check whether the public key entry does exist.
426 //
427 for (Index = 0; Index < mPubKeyNumber; Index++) {
428 if (CompareMem (((AUTHVAR_KEY_DB_DATA *) mPubKeyStore + Index)->KeyData, PubKey, EFI_CERT_TYPE_RSA2048_SIZE) == 0) {
429 return ReadUnaligned32 (&(((AUTHVAR_KEY_DB_DATA *) mPubKeyStore + Index)->KeyIndex));
430 }
431 }
432
433 KeyIndex = GetAvailableKeyIndex (PubKey);
434 if (KeyIndex == 0) {
435 return 0;
436 }
437
438 //
439 // Check the variable space for both public key and variable data.
440 //
441 PublicKeyEntry.VariableSize = (mPubKeyNumber + 1) * sizeof (AUTHVAR_KEY_DB_DATA);
442 PublicKeyEntry.Guid = &gEfiAuthenticatedVariableGuid;
443 PublicKeyEntry.Name = AUTHVAR_KEYDB_NAME;
444 Attributes = VARIABLE_ATTRIBUTE_NV_BS_RT | EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS;
445
446 if (!mAuthVarLibContextIn->CheckRemainingSpaceForConsistency (Attributes, &PublicKeyEntry, VariableDataEntry, NULL)) {
447 //
448 // No enough variable space.
449 //
450 return 0;
451 }
452
453 WriteUnaligned32 (&(((AUTHVAR_KEY_DB_DATA *) mPubKeyStore + mPubKeyNumber)->KeyIndex), KeyIndex);
454 CopyMem (((AUTHVAR_KEY_DB_DATA *) mPubKeyStore + mPubKeyNumber)->KeyData, PubKey, EFI_CERT_TYPE_RSA2048_SIZE);
455 mPubKeyNumber++;
456
457 //
458 // Update public key database variable.
459 //
460 Status = AuthServiceInternalUpdateVariable (
461 AUTHVAR_KEYDB_NAME,
462 &gEfiAuthenticatedVariableGuid,
463 mPubKeyStore,
464 mPubKeyNumber * sizeof (AUTHVAR_KEY_DB_DATA),
465 Attributes
466 );
467 if (EFI_ERROR (Status)) {
468 DEBUG ((EFI_D_ERROR, "Update public key database variable failure, Status = %r\n", Status));
469 return 0;
470 }
471
472 return KeyIndex;
473 }
474
475 /**
476 Verify data payload with AuthInfo in EFI_CERT_TYPE_RSA2048_SHA256_GUID type.
477 Follow the steps in UEFI2.2.
478
479 Caution: This function may receive untrusted input.
480 This function may be invoked in SMM mode, and datasize and data are external input.
481 This function will do basic validation, before parse the data.
482 This function will parse the authentication carefully to avoid security issues, like
483 buffer overflow, integer overflow.
484
485 @param[in] Data Pointer to data with AuthInfo.
486 @param[in] DataSize Size of Data.
487 @param[in] PubKey Public key used for verification.
488
489 @retval EFI_INVALID_PARAMETER Invalid parameter.
490 @retval EFI_SECURITY_VIOLATION If authentication failed.
491 @retval EFI_SUCCESS Authentication successful.
492
493 **/
494 EFI_STATUS
VerifyCounterBasedPayload(IN UINT8 * Data,IN UINTN DataSize,IN UINT8 * PubKey)495 VerifyCounterBasedPayload (
496 IN UINT8 *Data,
497 IN UINTN DataSize,
498 IN UINT8 *PubKey
499 )
500 {
501 BOOLEAN Status;
502 EFI_VARIABLE_AUTHENTICATION *CertData;
503 EFI_CERT_BLOCK_RSA_2048_SHA256 *CertBlock;
504 UINT8 Digest[SHA256_DIGEST_SIZE];
505 VOID *Rsa;
506 UINTN PayloadSize;
507
508 PayloadSize = DataSize - AUTHINFO_SIZE;
509 Rsa = NULL;
510 CertData = NULL;
511 CertBlock = NULL;
512
513 if (Data == NULL || PubKey == NULL) {
514 return EFI_INVALID_PARAMETER;
515 }
516
517 CertData = (EFI_VARIABLE_AUTHENTICATION *) Data;
518 CertBlock = (EFI_CERT_BLOCK_RSA_2048_SHA256 *) (CertData->AuthInfo.CertData);
519
520 //
521 // wCertificateType should be WIN_CERT_TYPE_EFI_GUID.
522 // Cert type should be EFI_CERT_TYPE_RSA2048_SHA256_GUID.
523 //
524 if ((CertData->AuthInfo.Hdr.wCertificateType != WIN_CERT_TYPE_EFI_GUID) ||
525 !CompareGuid (&CertData->AuthInfo.CertType, &gEfiCertTypeRsa2048Sha256Guid)) {
526 //
527 // Invalid AuthInfo type, return EFI_SECURITY_VIOLATION.
528 //
529 return EFI_SECURITY_VIOLATION;
530 }
531 //
532 // Hash data payload with SHA256.
533 //
534 ZeroMem (Digest, SHA256_DIGEST_SIZE);
535 Status = Sha256Init (mHashCtx);
536 if (!Status) {
537 goto Done;
538 }
539 Status = Sha256Update (mHashCtx, Data + AUTHINFO_SIZE, PayloadSize);
540 if (!Status) {
541 goto Done;
542 }
543 //
544 // Hash Size.
545 //
546 Status = Sha256Update (mHashCtx, &PayloadSize, sizeof (UINTN));
547 if (!Status) {
548 goto Done;
549 }
550 //
551 // Hash Monotonic Count.
552 //
553 Status = Sha256Update (mHashCtx, &CertData->MonotonicCount, sizeof (UINT64));
554 if (!Status) {
555 goto Done;
556 }
557 Status = Sha256Final (mHashCtx, Digest);
558 if (!Status) {
559 goto Done;
560 }
561 //
562 // Generate & Initialize RSA Context.
563 //
564 Rsa = RsaNew ();
565 ASSERT (Rsa != NULL);
566 //
567 // Set RSA Key Components.
568 // NOTE: Only N and E are needed to be set as RSA public key for signature verification.
569 //
570 Status = RsaSetKey (Rsa, RsaKeyN, PubKey, EFI_CERT_TYPE_RSA2048_SIZE);
571 if (!Status) {
572 goto Done;
573 }
574 Status = RsaSetKey (Rsa, RsaKeyE, mRsaE, sizeof (mRsaE));
575 if (!Status) {
576 goto Done;
577 }
578 //
579 // Verify the signature.
580 //
581 Status = RsaPkcs1Verify (
582 Rsa,
583 Digest,
584 SHA256_DIGEST_SIZE,
585 CertBlock->Signature,
586 EFI_CERT_TYPE_RSA2048_SHA256_SIZE
587 );
588
589 Done:
590 if (Rsa != NULL) {
591 RsaFree (Rsa);
592 }
593 if (Status) {
594 return EFI_SUCCESS;
595 } else {
596 return EFI_SECURITY_VIOLATION;
597 }
598 }
599
600 /**
601 Update platform mode.
602
603 @param[in] Mode SETUP_MODE or USER_MODE.
604
605 @return EFI_INVALID_PARAMETER Invalid parameter.
606 @return EFI_SUCCESS Update platform mode successfully.
607
608 **/
609 EFI_STATUS
UpdatePlatformMode(IN UINT32 Mode)610 UpdatePlatformMode (
611 IN UINT32 Mode
612 )
613 {
614 EFI_STATUS Status;
615 VOID *Data;
616 UINTN DataSize;
617 UINT8 SecureBootMode;
618 UINT8 SecureBootEnable;
619 UINTN VariableDataSize;
620
621 Status = AuthServiceInternalFindVariable (
622 EFI_SETUP_MODE_NAME,
623 &gEfiGlobalVariableGuid,
624 &Data,
625 &DataSize
626 );
627 if (EFI_ERROR (Status)) {
628 return Status;
629 }
630
631 //
632 // Update the value of SetupMode variable by a simple mem copy, this could avoid possible
633 // variable storage reclaim at runtime.
634 //
635 mPlatformMode = (UINT8) Mode;
636 CopyMem (Data, &mPlatformMode, sizeof(UINT8));
637
638 if (mAuthVarLibContextIn->AtRuntime ()) {
639 //
640 // SecureBoot Variable indicates whether the platform firmware is operating
641 // in Secure boot mode (1) or not (0), so we should not change SecureBoot
642 // Variable in runtime.
643 //
644 return Status;
645 }
646
647 //
648 // Check "SecureBoot" variable's existence.
649 // If it doesn't exist, firmware has no capability to perform driver signing verification,
650 // then set "SecureBoot" to 0.
651 //
652 Status = AuthServiceInternalFindVariable (
653 EFI_SECURE_BOOT_MODE_NAME,
654 &gEfiGlobalVariableGuid,
655 &Data,
656 &DataSize
657 );
658 //
659 // If "SecureBoot" variable exists, then check "SetupMode" variable update.
660 // If "SetupMode" variable is USER_MODE, "SecureBoot" variable is set to 1.
661 // If "SetupMode" variable is SETUP_MODE, "SecureBoot" variable is set to 0.
662 //
663 if (EFI_ERROR (Status)) {
664 SecureBootMode = SECURE_BOOT_MODE_DISABLE;
665 } else {
666 if (mPlatformMode == USER_MODE) {
667 SecureBootMode = SECURE_BOOT_MODE_ENABLE;
668 } else if (mPlatformMode == SETUP_MODE) {
669 SecureBootMode = SECURE_BOOT_MODE_DISABLE;
670 } else {
671 return EFI_NOT_FOUND;
672 }
673 }
674
675 Status = AuthServiceInternalUpdateVariable (
676 EFI_SECURE_BOOT_MODE_NAME,
677 &gEfiGlobalVariableGuid,
678 &SecureBootMode,
679 sizeof(UINT8),
680 EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS
681 );
682 if (EFI_ERROR (Status)) {
683 return Status;
684 }
685
686 //
687 // Check "SecureBootEnable" variable's existence. It can enable/disable secure boot feature.
688 //
689 Status = AuthServiceInternalFindVariable (
690 EFI_SECURE_BOOT_ENABLE_NAME,
691 &gEfiSecureBootEnableDisableGuid,
692 &Data,
693 &DataSize
694 );
695
696 if (SecureBootMode == SECURE_BOOT_MODE_ENABLE) {
697 //
698 // Create the "SecureBootEnable" variable as secure boot is enabled.
699 //
700 SecureBootEnable = SECURE_BOOT_ENABLE;
701 VariableDataSize = sizeof (SecureBootEnable);
702 } else {
703 //
704 // Delete the "SecureBootEnable" variable if this variable exist as "SecureBoot"
705 // variable is not in secure boot state.
706 //
707 if (EFI_ERROR (Status)) {
708 return EFI_SUCCESS;
709 }
710 SecureBootEnable = SECURE_BOOT_DISABLE;
711 VariableDataSize = 0;
712 }
713
714 Status = AuthServiceInternalUpdateVariable (
715 EFI_SECURE_BOOT_ENABLE_NAME,
716 &gEfiSecureBootEnableDisableGuid,
717 &SecureBootEnable,
718 VariableDataSize,
719 EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS
720 );
721 return Status;
722 }
723
724 /**
725 Check input data form to make sure it is a valid EFI_SIGNATURE_LIST for PK/KEK/db/dbx/dbt variable.
726
727 @param[in] VariableName Name of Variable to be check.
728 @param[in] VendorGuid Variable vendor GUID.
729 @param[in] Data Point to the variable data to be checked.
730 @param[in] DataSize Size of Data.
731
732 @return EFI_INVALID_PARAMETER Invalid signature list format.
733 @return EFI_SUCCESS Passed signature list format check successfully.
734
735 **/
736 EFI_STATUS
CheckSignatureListFormat(IN CHAR16 * VariableName,IN EFI_GUID * VendorGuid,IN VOID * Data,IN UINTN DataSize)737 CheckSignatureListFormat(
738 IN CHAR16 *VariableName,
739 IN EFI_GUID *VendorGuid,
740 IN VOID *Data,
741 IN UINTN DataSize
742 )
743 {
744 EFI_SIGNATURE_LIST *SigList;
745 UINTN SigDataSize;
746 UINT32 Index;
747 UINT32 SigCount;
748 BOOLEAN IsPk;
749 VOID *RsaContext;
750 EFI_SIGNATURE_DATA *CertData;
751 UINTN CertLen;
752
753 if (DataSize == 0) {
754 return EFI_SUCCESS;
755 }
756
757 ASSERT (VariableName != NULL && VendorGuid != NULL && Data != NULL);
758
759 if (CompareGuid (VendorGuid, &gEfiGlobalVariableGuid) && (StrCmp (VariableName, EFI_PLATFORM_KEY_NAME) == 0)){
760 IsPk = TRUE;
761 } else if ((CompareGuid (VendorGuid, &gEfiGlobalVariableGuid) && (StrCmp (VariableName, EFI_KEY_EXCHANGE_KEY_NAME) == 0)) ||
762 (CompareGuid (VendorGuid, &gEfiImageSecurityDatabaseGuid) &&
763 ((StrCmp (VariableName, EFI_IMAGE_SECURITY_DATABASE) == 0) || (StrCmp (VariableName, EFI_IMAGE_SECURITY_DATABASE1) == 0) ||
764 (StrCmp (VariableName, EFI_IMAGE_SECURITY_DATABASE2) == 0)))) {
765 IsPk = FALSE;
766 } else {
767 return EFI_SUCCESS;
768 }
769
770 SigCount = 0;
771 SigList = (EFI_SIGNATURE_LIST *) Data;
772 SigDataSize = DataSize;
773 RsaContext = NULL;
774
775 //
776 // Walk throuth the input signature list and check the data format.
777 // If any signature is incorrectly formed, the whole check will fail.
778 //
779 while ((SigDataSize > 0) && (SigDataSize >= SigList->SignatureListSize)) {
780 for (Index = 0; Index < (sizeof (mSupportSigItem) / sizeof (EFI_SIGNATURE_ITEM)); Index++ ) {
781 if (CompareGuid (&SigList->SignatureType, &mSupportSigItem[Index].SigType)) {
782 //
783 // The value of SignatureSize should always be 16 (size of SignatureOwner
784 // component) add the data length according to signature type.
785 //
786 if (mSupportSigItem[Index].SigDataSize != ((UINT32) ~0) &&
787 (SigList->SignatureSize - sizeof (EFI_GUID)) != mSupportSigItem[Index].SigDataSize) {
788 return EFI_INVALID_PARAMETER;
789 }
790 if (mSupportSigItem[Index].SigHeaderSize != ((UINT32) ~0) &&
791 SigList->SignatureHeaderSize != mSupportSigItem[Index].SigHeaderSize) {
792 return EFI_INVALID_PARAMETER;
793 }
794 break;
795 }
796 }
797
798 if (Index == (sizeof (mSupportSigItem) / sizeof (EFI_SIGNATURE_ITEM))) {
799 //
800 // Undefined signature type.
801 //
802 return EFI_INVALID_PARAMETER;
803 }
804
805 if (CompareGuid (&SigList->SignatureType, &gEfiCertX509Guid)) {
806 //
807 // Try to retrieve the RSA public key from the X.509 certificate.
808 // If this operation fails, it's not a valid certificate.
809 //
810 RsaContext = RsaNew ();
811 if (RsaContext == NULL) {
812 return EFI_INVALID_PARAMETER;
813 }
814 CertData = (EFI_SIGNATURE_DATA *) ((UINT8 *) SigList + sizeof (EFI_SIGNATURE_LIST) + SigList->SignatureHeaderSize);
815 CertLen = SigList->SignatureSize - sizeof (EFI_GUID);
816 if (!RsaGetPublicKeyFromX509 (CertData->SignatureData, CertLen, &RsaContext)) {
817 RsaFree (RsaContext);
818 return EFI_INVALID_PARAMETER;
819 }
820 RsaFree (RsaContext);
821 }
822
823 if ((SigList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - SigList->SignatureHeaderSize) % SigList->SignatureSize != 0) {
824 return EFI_INVALID_PARAMETER;
825 }
826 SigCount += (SigList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - SigList->SignatureHeaderSize) / SigList->SignatureSize;
827
828 SigDataSize -= SigList->SignatureListSize;
829 SigList = (EFI_SIGNATURE_LIST *) ((UINT8 *) SigList + SigList->SignatureListSize);
830 }
831
832 if (((UINTN) SigList - (UINTN) Data) != DataSize) {
833 return EFI_INVALID_PARAMETER;
834 }
835
836 if (IsPk && SigCount > 1) {
837 return EFI_INVALID_PARAMETER;
838 }
839
840 return EFI_SUCCESS;
841 }
842
843 /**
844 Update "VendorKeys" variable to record the out of band secure boot key modification.
845
846 @return EFI_SUCCESS Variable is updated successfully.
847 @return Others Failed to update variable.
848
849 **/
850 EFI_STATUS
VendorKeyIsModified(VOID)851 VendorKeyIsModified (
852 VOID
853 )
854 {
855 EFI_STATUS Status;
856
857 if (mVendorKeyState == VENDOR_KEYS_MODIFIED) {
858 return EFI_SUCCESS;
859 }
860 mVendorKeyState = VENDOR_KEYS_MODIFIED;
861
862 Status = AuthServiceInternalUpdateVariable (
863 EFI_VENDOR_KEYS_NV_VARIABLE_NAME,
864 &gEfiVendorKeysNvGuid,
865 &mVendorKeyState,
866 sizeof (UINT8),
867 EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS
868 );
869 if (EFI_ERROR (Status)) {
870 return Status;
871 }
872
873 return AuthServiceInternalUpdateVariable (
874 EFI_VENDOR_KEYS_VARIABLE_NAME,
875 &gEfiGlobalVariableGuid,
876 &mVendorKeyState,
877 sizeof (UINT8),
878 EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS
879 );
880 }
881
882 /**
883 Process variable with platform key for verification.
884
885 Caution: This function may receive untrusted input.
886 This function may be invoked in SMM mode, and datasize and data are external input.
887 This function will do basic validation, before parse the data.
888 This function will parse the authentication carefully to avoid security issues, like
889 buffer overflow, integer overflow.
890 This function will check attribute carefully to avoid authentication bypass.
891
892 @param[in] VariableName Name of Variable to be found.
893 @param[in] VendorGuid Variable vendor GUID.
894 @param[in] Data Data pointer.
895 @param[in] DataSize Size of Data found. If size is less than the
896 data, this value contains the required size.
897 @param[in] Attributes Attribute value of the variable
898 @param[in] IsPk Indicate whether it is to process pk.
899
900 @return EFI_INVALID_PARAMETER Invalid parameter.
901 @return EFI_SECURITY_VIOLATION The variable does NOT pass the validation.
902 check carried out by the firmware.
903 @return EFI_SUCCESS Variable passed validation successfully.
904
905 **/
906 EFI_STATUS
ProcessVarWithPk(IN CHAR16 * VariableName,IN EFI_GUID * VendorGuid,IN VOID * Data,IN UINTN DataSize,IN UINT32 Attributes OPTIONAL,IN BOOLEAN IsPk)907 ProcessVarWithPk (
908 IN CHAR16 *VariableName,
909 IN EFI_GUID *VendorGuid,
910 IN VOID *Data,
911 IN UINTN DataSize,
912 IN UINT32 Attributes OPTIONAL,
913 IN BOOLEAN IsPk
914 )
915 {
916 EFI_STATUS Status;
917 BOOLEAN Del;
918 UINT8 *Payload;
919 UINTN PayloadSize;
920
921 if ((Attributes & EFI_VARIABLE_NON_VOLATILE) == 0 ||
922 (Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) == 0) {
923 //
924 // PK, KEK and db/dbx/dbt should set EFI_VARIABLE_NON_VOLATILE attribute and should be a time-based
925 // authenticated variable.
926 //
927 return EFI_INVALID_PARAMETER;
928 }
929
930 //
931 // Init state of Del. State may change due to secure check
932 //
933 Del = FALSE;
934 if ((InCustomMode() && UserPhysicalPresent()) || (mPlatformMode == SETUP_MODE && !IsPk)) {
935 Payload = (UINT8 *) Data + AUTHINFO2_SIZE (Data);
936 PayloadSize = DataSize - AUTHINFO2_SIZE (Data);
937 if (PayloadSize == 0) {
938 Del = TRUE;
939 }
940
941 Status = CheckSignatureListFormat(VariableName, VendorGuid, Payload, PayloadSize);
942 if (EFI_ERROR (Status)) {
943 return Status;
944 }
945
946 Status = AuthServiceInternalUpdateVariableWithTimeStamp (
947 VariableName,
948 VendorGuid,
949 Payload,
950 PayloadSize,
951 Attributes,
952 &((EFI_VARIABLE_AUTHENTICATION_2 *) Data)->TimeStamp
953 );
954 if (EFI_ERROR(Status)) {
955 return Status;
956 }
957
958 if ((mPlatformMode != SETUP_MODE) || IsPk) {
959 Status = VendorKeyIsModified ();
960 }
961 } else if (mPlatformMode == USER_MODE) {
962 //
963 // Verify against X509 Cert in PK database.
964 //
965 Status = VerifyTimeBasedPayloadAndUpdate (
966 VariableName,
967 VendorGuid,
968 Data,
969 DataSize,
970 Attributes,
971 AuthVarTypePk,
972 &Del
973 );
974 } else {
975 //
976 // Verify against the certificate in data payload.
977 //
978 Status = VerifyTimeBasedPayloadAndUpdate (
979 VariableName,
980 VendorGuid,
981 Data,
982 DataSize,
983 Attributes,
984 AuthVarTypePayload,
985 &Del
986 );
987 }
988
989 if (!EFI_ERROR(Status) && IsPk) {
990 if (mPlatformMode == SETUP_MODE && !Del) {
991 //
992 // If enroll PK in setup mode, need change to user mode.
993 //
994 Status = UpdatePlatformMode (USER_MODE);
995 } else if (mPlatformMode == USER_MODE && Del){
996 //
997 // If delete PK in user mode, need change to setup mode.
998 //
999 Status = UpdatePlatformMode (SETUP_MODE);
1000 }
1001 }
1002
1003 return Status;
1004 }
1005
1006 /**
1007 Process variable with key exchange key for verification.
1008
1009 Caution: This function may receive untrusted input.
1010 This function may be invoked in SMM mode, and datasize and data are external input.
1011 This function will do basic validation, before parse the data.
1012 This function will parse the authentication carefully to avoid security issues, like
1013 buffer overflow, integer overflow.
1014 This function will check attribute carefully to avoid authentication bypass.
1015
1016 @param[in] VariableName Name of Variable to be found.
1017 @param[in] VendorGuid Variable vendor GUID.
1018 @param[in] Data Data pointer.
1019 @param[in] DataSize Size of Data found. If size is less than the
1020 data, this value contains the required size.
1021 @param[in] Attributes Attribute value of the variable.
1022
1023 @return EFI_INVALID_PARAMETER Invalid parameter.
1024 @return EFI_SECURITY_VIOLATION The variable does NOT pass the validation
1025 check carried out by the firmware.
1026 @return EFI_SUCCESS Variable pass validation successfully.
1027
1028 **/
1029 EFI_STATUS
ProcessVarWithKek(IN CHAR16 * VariableName,IN EFI_GUID * VendorGuid,IN VOID * Data,IN UINTN DataSize,IN UINT32 Attributes OPTIONAL)1030 ProcessVarWithKek (
1031 IN CHAR16 *VariableName,
1032 IN EFI_GUID *VendorGuid,
1033 IN VOID *Data,
1034 IN UINTN DataSize,
1035 IN UINT32 Attributes OPTIONAL
1036 )
1037 {
1038 EFI_STATUS Status;
1039 UINT8 *Payload;
1040 UINTN PayloadSize;
1041
1042 if ((Attributes & EFI_VARIABLE_NON_VOLATILE) == 0 ||
1043 (Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) == 0) {
1044 //
1045 // DB, DBX and DBT should set EFI_VARIABLE_NON_VOLATILE attribute and should be a time-based
1046 // authenticated variable.
1047 //
1048 return EFI_INVALID_PARAMETER;
1049 }
1050
1051 Status = EFI_SUCCESS;
1052 if (mPlatformMode == USER_MODE && !(InCustomMode() && UserPhysicalPresent())) {
1053 //
1054 // Time-based, verify against X509 Cert KEK.
1055 //
1056 return VerifyTimeBasedPayloadAndUpdate (
1057 VariableName,
1058 VendorGuid,
1059 Data,
1060 DataSize,
1061 Attributes,
1062 AuthVarTypeKek,
1063 NULL
1064 );
1065 } else {
1066 //
1067 // If in setup mode or custom secure boot mode, no authentication needed.
1068 //
1069 Payload = (UINT8 *) Data + AUTHINFO2_SIZE (Data);
1070 PayloadSize = DataSize - AUTHINFO2_SIZE (Data);
1071
1072 Status = CheckSignatureListFormat(VariableName, VendorGuid, Payload, PayloadSize);
1073 if (EFI_ERROR (Status)) {
1074 return Status;
1075 }
1076
1077 Status = AuthServiceInternalUpdateVariableWithTimeStamp (
1078 VariableName,
1079 VendorGuid,
1080 Payload,
1081 PayloadSize,
1082 Attributes,
1083 &((EFI_VARIABLE_AUTHENTICATION_2 *) Data)->TimeStamp
1084 );
1085 if (EFI_ERROR (Status)) {
1086 return Status;
1087 }
1088
1089 if (mPlatformMode != SETUP_MODE) {
1090 Status = VendorKeyIsModified ();
1091 }
1092 }
1093
1094 return Status;
1095 }
1096
1097 /**
1098 Check if it is to delete auth variable.
1099
1100 @param[in] OrgAttributes Original attribute value of the variable.
1101 @param[in] Data Data pointer.
1102 @param[in] DataSize Size of Data.
1103 @param[in] Attributes Attribute value of the variable.
1104
1105 @retval TRUE It is to delete auth variable.
1106 @retval FALSE It is not to delete auth variable.
1107
1108 **/
1109 BOOLEAN
IsDeleteAuthVariable(IN UINT32 OrgAttributes,IN VOID * Data,IN UINTN DataSize,IN UINT32 Attributes)1110 IsDeleteAuthVariable (
1111 IN UINT32 OrgAttributes,
1112 IN VOID *Data,
1113 IN UINTN DataSize,
1114 IN UINT32 Attributes
1115 )
1116 {
1117 BOOLEAN Del;
1118 UINTN PayloadSize;
1119
1120 Del = FALSE;
1121
1122 //
1123 // To delete a variable created with the EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS
1124 // or the EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS attribute,
1125 // SetVariable must be used with attributes matching the existing variable
1126 // and the DataSize set to the size of the AuthInfo descriptor.
1127 //
1128 if ((Attributes == OrgAttributes) &&
1129 ((Attributes & (EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS)) != 0)) {
1130 if ((Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) != 0) {
1131 PayloadSize = DataSize - AUTHINFO2_SIZE (Data);
1132 if (PayloadSize == 0) {
1133 Del = TRUE;
1134 }
1135 } else {
1136 PayloadSize = DataSize - AUTHINFO_SIZE;
1137 if (PayloadSize == 0) {
1138 Del = TRUE;
1139 }
1140 }
1141 }
1142
1143 return Del;
1144 }
1145
1146 /**
1147 Process variable with EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS/EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS set
1148
1149 Caution: This function may receive untrusted input.
1150 This function may be invoked in SMM mode, and datasize and data are external input.
1151 This function will do basic validation, before parse the data.
1152 This function will parse the authentication carefully to avoid security issues, like
1153 buffer overflow, integer overflow.
1154 This function will check attribute carefully to avoid authentication bypass.
1155
1156 @param[in] VariableName Name of the variable.
1157 @param[in] VendorGuid Variable vendor GUID.
1158 @param[in] Data Data pointer.
1159 @param[in] DataSize Size of Data.
1160 @param[in] Attributes Attribute value of the variable.
1161
1162 @return EFI_INVALID_PARAMETER Invalid parameter.
1163 @return EFI_WRITE_PROTECTED Variable is write-protected and needs authentication with
1164 EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS set.
1165 @return EFI_OUT_OF_RESOURCES The Database to save the public key is full.
1166 @return EFI_SECURITY_VIOLATION The variable is with EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS
1167 set, but the AuthInfo does NOT pass the validation
1168 check carried out by the firmware.
1169 @return EFI_SUCCESS Variable is not write-protected or pass validation successfully.
1170
1171 **/
1172 EFI_STATUS
ProcessVariable(IN CHAR16 * VariableName,IN EFI_GUID * VendorGuid,IN VOID * Data,IN UINTN DataSize,IN UINT32 Attributes)1173 ProcessVariable (
1174 IN CHAR16 *VariableName,
1175 IN EFI_GUID *VendorGuid,
1176 IN VOID *Data,
1177 IN UINTN DataSize,
1178 IN UINT32 Attributes
1179 )
1180 {
1181 EFI_STATUS Status;
1182 BOOLEAN IsDeletion;
1183 BOOLEAN IsFirstTime;
1184 UINT8 *PubKey;
1185 EFI_VARIABLE_AUTHENTICATION *CertData;
1186 EFI_CERT_BLOCK_RSA_2048_SHA256 *CertBlock;
1187 UINT32 KeyIndex;
1188 UINT64 MonotonicCount;
1189 VARIABLE_ENTRY_CONSISTENCY VariableDataEntry;
1190 UINT32 Index;
1191 AUTH_VARIABLE_INFO OrgVariableInfo;
1192
1193 KeyIndex = 0;
1194 CertData = NULL;
1195 CertBlock = NULL;
1196 PubKey = NULL;
1197 IsDeletion = FALSE;
1198 Status = EFI_SUCCESS;
1199
1200 ZeroMem (&OrgVariableInfo, sizeof (OrgVariableInfo));
1201 Status = mAuthVarLibContextIn->FindVariable (
1202 VariableName,
1203 VendorGuid,
1204 &OrgVariableInfo
1205 );
1206
1207 if ((!EFI_ERROR (Status)) && IsDeleteAuthVariable (OrgVariableInfo.Attributes, Data, DataSize, Attributes) && UserPhysicalPresent()) {
1208 //
1209 // Allow the delete operation of common authenticated variable at user physical presence.
1210 //
1211 Status = AuthServiceInternalUpdateVariable (
1212 VariableName,
1213 VendorGuid,
1214 NULL,
1215 0,
1216 0
1217 );
1218 if (!EFI_ERROR (Status) && ((Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) != 0)) {
1219 Status = DeleteCertsFromDb (VariableName, VendorGuid, Attributes);
1220 }
1221
1222 return Status;
1223 }
1224
1225 if (NeedPhysicallyPresent (VariableName, VendorGuid) && !UserPhysicalPresent()) {
1226 //
1227 // This variable is protected, only physical present user could modify its value.
1228 //
1229 return EFI_SECURITY_VIOLATION;
1230 }
1231
1232 //
1233 // A time-based authenticated variable and a count-based authenticated variable
1234 // can't be updated by each other.
1235 //
1236 if (OrgVariableInfo.Data != NULL) {
1237 if (((Attributes & EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS) != 0) &&
1238 ((OrgVariableInfo.Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) != 0)) {
1239 return EFI_SECURITY_VIOLATION;
1240 }
1241
1242 if (((Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) != 0) &&
1243 ((OrgVariableInfo.Attributes & EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS) != 0)) {
1244 return EFI_SECURITY_VIOLATION;
1245 }
1246 }
1247
1248 //
1249 // Process Time-based Authenticated variable.
1250 //
1251 if ((Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) != 0) {
1252 return VerifyTimeBasedPayloadAndUpdate (
1253 VariableName,
1254 VendorGuid,
1255 Data,
1256 DataSize,
1257 Attributes,
1258 AuthVarTypePriv,
1259 NULL
1260 );
1261 }
1262
1263 //
1264 // Determine if first time SetVariable with the EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS.
1265 //
1266 if ((Attributes & EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS) != 0) {
1267 //
1268 // Determine current operation type.
1269 //
1270 if (DataSize == AUTHINFO_SIZE) {
1271 IsDeletion = TRUE;
1272 }
1273 //
1274 // Determine whether this is the first time with EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS set.
1275 //
1276 if (OrgVariableInfo.Data == NULL) {
1277 IsFirstTime = TRUE;
1278 } else if ((OrgVariableInfo.Attributes & EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS) == 0) {
1279 IsFirstTime = TRUE;
1280 } else {
1281 KeyIndex = OrgVariableInfo.PubKeyIndex;
1282 IsFirstTime = FALSE;
1283 }
1284 } else if ((OrgVariableInfo.Data != NULL) &&
1285 ((OrgVariableInfo.Attributes & (EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS)) != 0)
1286 ) {
1287 //
1288 // If the variable is already write-protected, it always needs authentication before update.
1289 //
1290 return EFI_WRITE_PROTECTED;
1291 } else {
1292 //
1293 // If without EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS, set and attributes collision.
1294 // That means it is not authenticated variable, just update variable as usual.
1295 //
1296 Status = AuthServiceInternalUpdateVariable (VariableName, VendorGuid, Data, DataSize, Attributes);
1297 return Status;
1298 }
1299
1300 //
1301 // Get PubKey and check Monotonic Count value corresponding to the variable.
1302 //
1303 CertData = (EFI_VARIABLE_AUTHENTICATION *) Data;
1304 CertBlock = (EFI_CERT_BLOCK_RSA_2048_SHA256 *) (CertData->AuthInfo.CertData);
1305 PubKey = CertBlock->PublicKey;
1306
1307 //
1308 // Update Monotonic Count value.
1309 //
1310 MonotonicCount = CertData->MonotonicCount;
1311
1312 if (!IsFirstTime) {
1313 //
1314 // 2 cases need to check here
1315 // 1. Internal PubKey variable. PubKeyIndex is always 0
1316 // 2. Other counter-based AuthVariable. Check input PubKey.
1317 //
1318 if (KeyIndex == 0) {
1319 return EFI_SECURITY_VIOLATION;
1320 }
1321 for (Index = 0; Index < mPubKeyNumber; Index++) {
1322 if (ReadUnaligned32 (&(((AUTHVAR_KEY_DB_DATA *) mPubKeyStore + Index)->KeyIndex)) == KeyIndex) {
1323 if (CompareMem (((AUTHVAR_KEY_DB_DATA *) mPubKeyStore + Index)->KeyData, PubKey, EFI_CERT_TYPE_RSA2048_SIZE) == 0) {
1324 break;
1325 } else {
1326 return EFI_SECURITY_VIOLATION;
1327 }
1328 }
1329 }
1330 if (Index == mPubKeyNumber) {
1331 return EFI_SECURITY_VIOLATION;
1332 }
1333
1334 //
1335 // Compare the current monotonic count and ensure that it is greater than the last SetVariable
1336 // operation with the EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS attribute set.
1337 //
1338 if (MonotonicCount <= OrgVariableInfo.MonotonicCount) {
1339 //
1340 // Monotonic count check fail, suspicious replay attack, return EFI_SECURITY_VIOLATION.
1341 //
1342 return EFI_SECURITY_VIOLATION;
1343 }
1344 }
1345 //
1346 // Verify the certificate in Data payload.
1347 //
1348 Status = VerifyCounterBasedPayload (Data, DataSize, PubKey);
1349 if (EFI_ERROR (Status)) {
1350 return Status;
1351 }
1352
1353 //
1354 // Now, the signature has been verified!
1355 //
1356 if (IsFirstTime && !IsDeletion) {
1357 VariableDataEntry.VariableSize = DataSize - AUTHINFO_SIZE;
1358 VariableDataEntry.Guid = VendorGuid;
1359 VariableDataEntry.Name = VariableName;
1360
1361 //
1362 // Update public key database variable if need.
1363 //
1364 KeyIndex = AddPubKeyInStore (PubKey, &VariableDataEntry);
1365 if (KeyIndex == 0) {
1366 return EFI_OUT_OF_RESOURCES;
1367 }
1368 }
1369
1370 //
1371 // Verification pass.
1372 //
1373 return AuthServiceInternalUpdateVariableWithMonotonicCount (VariableName, VendorGuid, (UINT8*)Data + AUTHINFO_SIZE, DataSize - AUTHINFO_SIZE, Attributes, KeyIndex, MonotonicCount);
1374 }
1375
1376 /**
1377 Filter out the duplicated EFI_SIGNATURE_DATA from the new data by comparing to the original data.
1378
1379 @param[in] Data Pointer to original EFI_SIGNATURE_LIST.
1380 @param[in] DataSize Size of Data buffer.
1381 @param[in, out] NewData Pointer to new EFI_SIGNATURE_LIST.
1382 @param[in, out] NewDataSize Size of NewData buffer.
1383
1384 **/
1385 EFI_STATUS
FilterSignatureList(IN VOID * Data,IN UINTN DataSize,IN OUT VOID * NewData,IN OUT UINTN * NewDataSize)1386 FilterSignatureList (
1387 IN VOID *Data,
1388 IN UINTN DataSize,
1389 IN OUT VOID *NewData,
1390 IN OUT UINTN *NewDataSize
1391 )
1392 {
1393 EFI_SIGNATURE_LIST *CertList;
1394 EFI_SIGNATURE_DATA *Cert;
1395 UINTN CertCount;
1396 EFI_SIGNATURE_LIST *NewCertList;
1397 EFI_SIGNATURE_DATA *NewCert;
1398 UINTN NewCertCount;
1399 UINTN Index;
1400 UINTN Index2;
1401 UINTN Size;
1402 UINT8 *Tail;
1403 UINTN CopiedCount;
1404 UINTN SignatureListSize;
1405 BOOLEAN IsNewCert;
1406 UINT8 *TempData;
1407 UINTN TempDataSize;
1408 EFI_STATUS Status;
1409
1410 if (*NewDataSize == 0) {
1411 return EFI_SUCCESS;
1412 }
1413
1414 TempDataSize = *NewDataSize;
1415 Status = mAuthVarLibContextIn->GetScratchBuffer (&TempDataSize, (VOID **) &TempData);
1416 if (EFI_ERROR (Status)) {
1417 return EFI_OUT_OF_RESOURCES;
1418 }
1419
1420 Tail = TempData;
1421
1422 NewCertList = (EFI_SIGNATURE_LIST *) NewData;
1423 while ((*NewDataSize > 0) && (*NewDataSize >= NewCertList->SignatureListSize)) {
1424 NewCert = (EFI_SIGNATURE_DATA *) ((UINT8 *) NewCertList + sizeof (EFI_SIGNATURE_LIST) + NewCertList->SignatureHeaderSize);
1425 NewCertCount = (NewCertList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - NewCertList->SignatureHeaderSize) / NewCertList->SignatureSize;
1426
1427 CopiedCount = 0;
1428 for (Index = 0; Index < NewCertCount; Index++) {
1429 IsNewCert = TRUE;
1430
1431 Size = DataSize;
1432 CertList = (EFI_SIGNATURE_LIST *) Data;
1433 while ((Size > 0) && (Size >= CertList->SignatureListSize)) {
1434 if (CompareGuid (&CertList->SignatureType, &NewCertList->SignatureType) &&
1435 (CertList->SignatureSize == NewCertList->SignatureSize)) {
1436 Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize);
1437 CertCount = (CertList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - CertList->SignatureHeaderSize) / CertList->SignatureSize;
1438 for (Index2 = 0; Index2 < CertCount; Index2++) {
1439 //
1440 // Iterate each Signature Data in this Signature List.
1441 //
1442 if (CompareMem (NewCert, Cert, CertList->SignatureSize) == 0) {
1443 IsNewCert = FALSE;
1444 break;
1445 }
1446 Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) Cert + CertList->SignatureSize);
1447 }
1448 }
1449
1450 if (!IsNewCert) {
1451 break;
1452 }
1453 Size -= CertList->SignatureListSize;
1454 CertList = (EFI_SIGNATURE_LIST *) ((UINT8 *) CertList + CertList->SignatureListSize);
1455 }
1456
1457 if (IsNewCert) {
1458 //
1459 // New EFI_SIGNATURE_DATA, keep it.
1460 //
1461 if (CopiedCount == 0) {
1462 //
1463 // Copy EFI_SIGNATURE_LIST header for only once.
1464 //
1465 CopyMem (Tail, NewCertList, sizeof (EFI_SIGNATURE_LIST) + NewCertList->SignatureHeaderSize);
1466 Tail = Tail + sizeof (EFI_SIGNATURE_LIST) + NewCertList->SignatureHeaderSize;
1467 }
1468
1469 CopyMem (Tail, NewCert, NewCertList->SignatureSize);
1470 Tail += NewCertList->SignatureSize;
1471 CopiedCount++;
1472 }
1473
1474 NewCert = (EFI_SIGNATURE_DATA *) ((UINT8 *) NewCert + NewCertList->SignatureSize);
1475 }
1476
1477 //
1478 // Update SignatureListSize in the kept EFI_SIGNATURE_LIST.
1479 //
1480 if (CopiedCount != 0) {
1481 SignatureListSize = sizeof (EFI_SIGNATURE_LIST) + NewCertList->SignatureHeaderSize + (CopiedCount * NewCertList->SignatureSize);
1482 CertList = (EFI_SIGNATURE_LIST *) (Tail - SignatureListSize);
1483 CertList->SignatureListSize = (UINT32) SignatureListSize;
1484 }
1485
1486 *NewDataSize -= NewCertList->SignatureListSize;
1487 NewCertList = (EFI_SIGNATURE_LIST *) ((UINT8 *) NewCertList + NewCertList->SignatureListSize);
1488 }
1489
1490 TempDataSize = (Tail - (UINT8 *) TempData);
1491
1492 CopyMem (NewData, TempData, TempDataSize);
1493 *NewDataSize = TempDataSize;
1494
1495 return EFI_SUCCESS;
1496 }
1497
1498 /**
1499 Compare two EFI_TIME data.
1500
1501
1502 @param FirstTime A pointer to the first EFI_TIME data.
1503 @param SecondTime A pointer to the second EFI_TIME data.
1504
1505 @retval TRUE The FirstTime is not later than the SecondTime.
1506 @retval FALSE The FirstTime is later than the SecondTime.
1507
1508 **/
1509 BOOLEAN
AuthServiceInternalCompareTimeStamp(IN EFI_TIME * FirstTime,IN EFI_TIME * SecondTime)1510 AuthServiceInternalCompareTimeStamp (
1511 IN EFI_TIME *FirstTime,
1512 IN EFI_TIME *SecondTime
1513 )
1514 {
1515 if (FirstTime->Year != SecondTime->Year) {
1516 return (BOOLEAN) (FirstTime->Year < SecondTime->Year);
1517 } else if (FirstTime->Month != SecondTime->Month) {
1518 return (BOOLEAN) (FirstTime->Month < SecondTime->Month);
1519 } else if (FirstTime->Day != SecondTime->Day) {
1520 return (BOOLEAN) (FirstTime->Day < SecondTime->Day);
1521 } else if (FirstTime->Hour != SecondTime->Hour) {
1522 return (BOOLEAN) (FirstTime->Hour < SecondTime->Hour);
1523 } else if (FirstTime->Minute != SecondTime->Minute) {
1524 return (BOOLEAN) (FirstTime->Minute < SecondTime->Minute);
1525 }
1526
1527 return (BOOLEAN) (FirstTime->Second <= SecondTime->Second);
1528 }
1529
1530 /**
1531 Find matching signer's certificates for common authenticated variable
1532 by corresponding VariableName and VendorGuid from "certdb" or "certdbv".
1533
1534 The data format of "certdb" or "certdbv":
1535 //
1536 // UINT32 CertDbListSize;
1537 // /// AUTH_CERT_DB_DATA Certs1[];
1538 // /// AUTH_CERT_DB_DATA Certs2[];
1539 // /// ...
1540 // /// AUTH_CERT_DB_DATA Certsn[];
1541 //
1542
1543 @param[in] VariableName Name of authenticated Variable.
1544 @param[in] VendorGuid Vendor GUID of authenticated Variable.
1545 @param[in] Data Pointer to variable "certdb" or "certdbv".
1546 @param[in] DataSize Size of variable "certdb" or "certdbv".
1547 @param[out] CertOffset Offset of matching CertData, from starting of Data.
1548 @param[out] CertDataSize Length of CertData in bytes.
1549 @param[out] CertNodeOffset Offset of matching AUTH_CERT_DB_DATA , from
1550 starting of Data.
1551 @param[out] CertNodeSize Length of AUTH_CERT_DB_DATA in bytes.
1552
1553 @retval EFI_INVALID_PARAMETER Any input parameter is invalid.
1554 @retval EFI_NOT_FOUND Fail to find matching certs.
1555 @retval EFI_SUCCESS Find matching certs and output parameters.
1556
1557 **/
1558 EFI_STATUS
FindCertsFromDb(IN CHAR16 * VariableName,IN EFI_GUID * VendorGuid,IN UINT8 * Data,IN UINTN DataSize,OUT UINT32 * CertOffset,OPTIONAL OUT UINT32 * CertDataSize,OPTIONAL OUT UINT32 * CertNodeOffset,OPTIONAL OUT UINT32 * CertNodeSize OPTIONAL)1559 FindCertsFromDb (
1560 IN CHAR16 *VariableName,
1561 IN EFI_GUID *VendorGuid,
1562 IN UINT8 *Data,
1563 IN UINTN DataSize,
1564 OUT UINT32 *CertOffset, OPTIONAL
1565 OUT UINT32 *CertDataSize, OPTIONAL
1566 OUT UINT32 *CertNodeOffset,OPTIONAL
1567 OUT UINT32 *CertNodeSize OPTIONAL
1568 )
1569 {
1570 UINT32 Offset;
1571 AUTH_CERT_DB_DATA *Ptr;
1572 UINT32 CertSize;
1573 UINT32 NameSize;
1574 UINT32 NodeSize;
1575 UINT32 CertDbListSize;
1576
1577 if ((VariableName == NULL) || (VendorGuid == NULL) || (Data == NULL)) {
1578 return EFI_INVALID_PARAMETER;
1579 }
1580
1581 //
1582 // Check whether DataSize matches recorded CertDbListSize.
1583 //
1584 if (DataSize < sizeof (UINT32)) {
1585 return EFI_INVALID_PARAMETER;
1586 }
1587
1588 CertDbListSize = ReadUnaligned32 ((UINT32 *) Data);
1589
1590 if (CertDbListSize != (UINT32) DataSize) {
1591 return EFI_INVALID_PARAMETER;
1592 }
1593
1594 Offset = sizeof (UINT32);
1595
1596 //
1597 // Get corresponding certificates by VendorGuid and VariableName.
1598 //
1599 while (Offset < (UINT32) DataSize) {
1600 Ptr = (AUTH_CERT_DB_DATA *) (Data + Offset);
1601 //
1602 // Check whether VendorGuid matches.
1603 //
1604 if (CompareGuid (&Ptr->VendorGuid, VendorGuid)) {
1605 NodeSize = ReadUnaligned32 (&Ptr->CertNodeSize);
1606 NameSize = ReadUnaligned32 (&Ptr->NameSize);
1607 CertSize = ReadUnaligned32 (&Ptr->CertDataSize);
1608
1609 if (NodeSize != sizeof (EFI_GUID) + sizeof (UINT32) * 3 + CertSize +
1610 sizeof (CHAR16) * NameSize) {
1611 return EFI_INVALID_PARAMETER;
1612 }
1613
1614 Offset = Offset + sizeof (EFI_GUID) + sizeof (UINT32) * 3;
1615 //
1616 // Check whether VariableName matches.
1617 //
1618 if ((NameSize == StrLen (VariableName)) &&
1619 (CompareMem (Data + Offset, VariableName, NameSize * sizeof (CHAR16)) == 0)) {
1620 Offset = Offset + NameSize * sizeof (CHAR16);
1621
1622 if (CertOffset != NULL) {
1623 *CertOffset = Offset;
1624 }
1625
1626 if (CertDataSize != NULL) {
1627 *CertDataSize = CertSize;
1628 }
1629
1630 if (CertNodeOffset != NULL) {
1631 *CertNodeOffset = (UINT32) ((UINT8 *) Ptr - Data);
1632 }
1633
1634 if (CertNodeSize != NULL) {
1635 *CertNodeSize = NodeSize;
1636 }
1637
1638 return EFI_SUCCESS;
1639 } else {
1640 Offset = Offset + NameSize * sizeof (CHAR16) + CertSize;
1641 }
1642 } else {
1643 NodeSize = ReadUnaligned32 (&Ptr->CertNodeSize);
1644 Offset = Offset + NodeSize;
1645 }
1646 }
1647
1648 return EFI_NOT_FOUND;
1649 }
1650
1651 /**
1652 Retrieve signer's certificates for common authenticated variable
1653 by corresponding VariableName and VendorGuid from "certdb"
1654 or "certdbv" according to authenticated variable attributes.
1655
1656 @param[in] VariableName Name of authenticated Variable.
1657 @param[in] VendorGuid Vendor GUID of authenticated Variable.
1658 @param[in] Attributes Attributes of authenticated variable.
1659 @param[out] CertData Pointer to signer's certificates.
1660 @param[out] CertDataSize Length of CertData in bytes.
1661
1662 @retval EFI_INVALID_PARAMETER Any input parameter is invalid.
1663 @retval EFI_NOT_FOUND Fail to find "certdb"/"certdbv" or matching certs.
1664 @retval EFI_SUCCESS Get signer's certificates successfully.
1665
1666 **/
1667 EFI_STATUS
GetCertsFromDb(IN CHAR16 * VariableName,IN EFI_GUID * VendorGuid,IN UINT32 Attributes,OUT UINT8 ** CertData,OUT UINT32 * CertDataSize)1668 GetCertsFromDb (
1669 IN CHAR16 *VariableName,
1670 IN EFI_GUID *VendorGuid,
1671 IN UINT32 Attributes,
1672 OUT UINT8 **CertData,
1673 OUT UINT32 *CertDataSize
1674 )
1675 {
1676 EFI_STATUS Status;
1677 UINT8 *Data;
1678 UINTN DataSize;
1679 UINT32 CertOffset;
1680 CHAR16 *DbName;
1681
1682 if ((VariableName == NULL) || (VendorGuid == NULL) || (CertData == NULL) || (CertDataSize == NULL)) {
1683 return EFI_INVALID_PARAMETER;
1684 }
1685
1686
1687 if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
1688 //
1689 // Get variable "certdb".
1690 //
1691 DbName = EFI_CERT_DB_NAME;
1692 } else {
1693 //
1694 // Get variable "certdbv".
1695 //
1696 DbName = EFI_CERT_DB_VOLATILE_NAME;
1697 }
1698
1699 //
1700 // Get variable "certdb" or "certdbv".
1701 //
1702 Status = AuthServiceInternalFindVariable (
1703 DbName,
1704 &gEfiCertDbGuid,
1705 (VOID **) &Data,
1706 &DataSize
1707 );
1708 if (EFI_ERROR (Status)) {
1709 return Status;
1710 }
1711
1712 if ((DataSize == 0) || (Data == NULL)) {
1713 ASSERT (FALSE);
1714 return EFI_NOT_FOUND;
1715 }
1716
1717 Status = FindCertsFromDb (
1718 VariableName,
1719 VendorGuid,
1720 Data,
1721 DataSize,
1722 &CertOffset,
1723 CertDataSize,
1724 NULL,
1725 NULL
1726 );
1727
1728 if (EFI_ERROR (Status)) {
1729 return Status;
1730 }
1731
1732 *CertData = Data + CertOffset;
1733 return EFI_SUCCESS;
1734 }
1735
1736 /**
1737 Delete matching signer's certificates when deleting common authenticated
1738 variable by corresponding VariableName and VendorGuid from "certdb" or
1739 "certdbv" according to authenticated variable attributes.
1740
1741 @param[in] VariableName Name of authenticated Variable.
1742 @param[in] VendorGuid Vendor GUID of authenticated Variable.
1743 @param[in] Attributes Attributes of authenticated variable.
1744
1745 @retval EFI_INVALID_PARAMETER Any input parameter is invalid.
1746 @retval EFI_NOT_FOUND Fail to find "certdb"/"certdbv" or matching certs.
1747 @retval EFI_OUT_OF_RESOURCES The operation is failed due to lack of resources.
1748 @retval EFI_SUCCESS The operation is completed successfully.
1749
1750 **/
1751 EFI_STATUS
DeleteCertsFromDb(IN CHAR16 * VariableName,IN EFI_GUID * VendorGuid,IN UINT32 Attributes)1752 DeleteCertsFromDb (
1753 IN CHAR16 *VariableName,
1754 IN EFI_GUID *VendorGuid,
1755 IN UINT32 Attributes
1756 )
1757 {
1758 EFI_STATUS Status;
1759 UINT8 *Data;
1760 UINTN DataSize;
1761 UINT32 VarAttr;
1762 UINT32 CertNodeOffset;
1763 UINT32 CertNodeSize;
1764 UINT8 *NewCertDb;
1765 UINT32 NewCertDbSize;
1766 CHAR16 *DbName;
1767
1768 if ((VariableName == NULL) || (VendorGuid == NULL)) {
1769 return EFI_INVALID_PARAMETER;
1770 }
1771
1772 if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
1773 //
1774 // Get variable "certdb".
1775 //
1776 DbName = EFI_CERT_DB_NAME;
1777 VarAttr = EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS;
1778 } else {
1779 //
1780 // Get variable "certdbv".
1781 //
1782 DbName = EFI_CERT_DB_VOLATILE_NAME;
1783 VarAttr = EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS;
1784 }
1785
1786 Status = AuthServiceInternalFindVariable (
1787 DbName,
1788 &gEfiCertDbGuid,
1789 (VOID **) &Data,
1790 &DataSize
1791 );
1792
1793 if (EFI_ERROR (Status)) {
1794 return Status;
1795 }
1796
1797 if ((DataSize == 0) || (Data == NULL)) {
1798 ASSERT (FALSE);
1799 return EFI_NOT_FOUND;
1800 }
1801
1802 if (DataSize == sizeof (UINT32)) {
1803 //
1804 // There is no certs in "certdb" or "certdbv".
1805 //
1806 return EFI_SUCCESS;
1807 }
1808
1809 //
1810 // Get corresponding cert node from "certdb" or "certdbv".
1811 //
1812 Status = FindCertsFromDb (
1813 VariableName,
1814 VendorGuid,
1815 Data,
1816 DataSize,
1817 NULL,
1818 NULL,
1819 &CertNodeOffset,
1820 &CertNodeSize
1821 );
1822
1823 if (EFI_ERROR (Status)) {
1824 return Status;
1825 }
1826
1827 if (DataSize < (CertNodeOffset + CertNodeSize)) {
1828 return EFI_NOT_FOUND;
1829 }
1830
1831 //
1832 // Construct new data content of variable "certdb" or "certdbv".
1833 //
1834 NewCertDbSize = (UINT32) DataSize - CertNodeSize;
1835 NewCertDb = (UINT8*) mCertDbStore;
1836
1837 //
1838 // Copy the DB entries before deleting node.
1839 //
1840 CopyMem (NewCertDb, Data, CertNodeOffset);
1841 //
1842 // Update CertDbListSize.
1843 //
1844 CopyMem (NewCertDb, &NewCertDbSize, sizeof (UINT32));
1845 //
1846 // Copy the DB entries after deleting node.
1847 //
1848 if (DataSize > (CertNodeOffset + CertNodeSize)) {
1849 CopyMem (
1850 NewCertDb + CertNodeOffset,
1851 Data + CertNodeOffset + CertNodeSize,
1852 DataSize - CertNodeOffset - CertNodeSize
1853 );
1854 }
1855
1856 //
1857 // Set "certdb" or "certdbv".
1858 //
1859 Status = AuthServiceInternalUpdateVariable (
1860 DbName,
1861 &gEfiCertDbGuid,
1862 NewCertDb,
1863 NewCertDbSize,
1864 VarAttr
1865 );
1866
1867 return Status;
1868 }
1869
1870 /**
1871 Insert signer's certificates for common authenticated variable with VariableName
1872 and VendorGuid in AUTH_CERT_DB_DATA to "certdb" or "certdbv" according to
1873 time based authenticated variable attributes.
1874
1875 @param[in] VariableName Name of authenticated Variable.
1876 @param[in] VendorGuid Vendor GUID of authenticated Variable.
1877 @param[in] Attributes Attributes of authenticated variable.
1878 @param[in] CertData Pointer to signer's certificates.
1879 @param[in] CertDataSize Length of CertData in bytes.
1880
1881 @retval EFI_INVALID_PARAMETER Any input parameter is invalid.
1882 @retval EFI_ACCESS_DENIED An AUTH_CERT_DB_DATA entry with same VariableName
1883 and VendorGuid already exists.
1884 @retval EFI_OUT_OF_RESOURCES The operation is failed due to lack of resources.
1885 @retval EFI_SUCCESS Insert an AUTH_CERT_DB_DATA entry to "certdb" or "certdbv"
1886
1887 **/
1888 EFI_STATUS
InsertCertsToDb(IN CHAR16 * VariableName,IN EFI_GUID * VendorGuid,IN UINT32 Attributes,IN UINT8 * CertData,IN UINTN CertDataSize)1889 InsertCertsToDb (
1890 IN CHAR16 *VariableName,
1891 IN EFI_GUID *VendorGuid,
1892 IN UINT32 Attributes,
1893 IN UINT8 *CertData,
1894 IN UINTN CertDataSize
1895 )
1896 {
1897 EFI_STATUS Status;
1898 UINT8 *Data;
1899 UINTN DataSize;
1900 UINT32 VarAttr;
1901 UINT8 *NewCertDb;
1902 UINT32 NewCertDbSize;
1903 UINT32 CertNodeSize;
1904 UINT32 NameSize;
1905 AUTH_CERT_DB_DATA *Ptr;
1906 CHAR16 *DbName;
1907
1908 if ((VariableName == NULL) || (VendorGuid == NULL) || (CertData == NULL)) {
1909 return EFI_INVALID_PARAMETER;
1910 }
1911
1912 if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
1913 //
1914 // Get variable "certdb".
1915 //
1916 DbName = EFI_CERT_DB_NAME;
1917 VarAttr = EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS;
1918 } else {
1919 //
1920 // Get variable "certdbv".
1921 //
1922 DbName = EFI_CERT_DB_VOLATILE_NAME;
1923 VarAttr = EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS;
1924 }
1925
1926 //
1927 // Get variable "certdb" or "certdbv".
1928 //
1929 Status = AuthServiceInternalFindVariable (
1930 DbName,
1931 &gEfiCertDbGuid,
1932 (VOID **) &Data,
1933 &DataSize
1934 );
1935 if (EFI_ERROR (Status)) {
1936 return Status;
1937 }
1938
1939 if ((DataSize == 0) || (Data == NULL)) {
1940 ASSERT (FALSE);
1941 return EFI_NOT_FOUND;
1942 }
1943
1944 //
1945 // Find whether matching cert node already exists in "certdb" or "certdbv".
1946 // If yes return error.
1947 //
1948 Status = FindCertsFromDb (
1949 VariableName,
1950 VendorGuid,
1951 Data,
1952 DataSize,
1953 NULL,
1954 NULL,
1955 NULL,
1956 NULL
1957 );
1958
1959 if (!EFI_ERROR (Status)) {
1960 ASSERT (FALSE);
1961 return EFI_ACCESS_DENIED;
1962 }
1963
1964 //
1965 // Construct new data content of variable "certdb" or "certdbv".
1966 //
1967 NameSize = (UINT32) StrLen (VariableName);
1968 CertNodeSize = sizeof (AUTH_CERT_DB_DATA) + (UINT32) CertDataSize + NameSize * sizeof (CHAR16);
1969 NewCertDbSize = (UINT32) DataSize + CertNodeSize;
1970 if (NewCertDbSize > mMaxCertDbSize) {
1971 return EFI_OUT_OF_RESOURCES;
1972 }
1973 NewCertDb = (UINT8*) mCertDbStore;
1974
1975 //
1976 // Copy the DB entries before inserting node.
1977 //
1978 CopyMem (NewCertDb, Data, DataSize);
1979 //
1980 // Update CertDbListSize.
1981 //
1982 CopyMem (NewCertDb, &NewCertDbSize, sizeof (UINT32));
1983 //
1984 // Construct new cert node.
1985 //
1986 Ptr = (AUTH_CERT_DB_DATA *) (NewCertDb + DataSize);
1987 CopyGuid (&Ptr->VendorGuid, VendorGuid);
1988 CopyMem (&Ptr->CertNodeSize, &CertNodeSize, sizeof (UINT32));
1989 CopyMem (&Ptr->NameSize, &NameSize, sizeof (UINT32));
1990 CopyMem (&Ptr->CertDataSize, &CertDataSize, sizeof (UINT32));
1991
1992 CopyMem (
1993 (UINT8 *) Ptr + sizeof (AUTH_CERT_DB_DATA),
1994 VariableName,
1995 NameSize * sizeof (CHAR16)
1996 );
1997
1998 CopyMem (
1999 (UINT8 *) Ptr + sizeof (AUTH_CERT_DB_DATA) + NameSize * sizeof (CHAR16),
2000 CertData,
2001 CertDataSize
2002 );
2003
2004 //
2005 // Set "certdb" or "certdbv".
2006 //
2007 Status = AuthServiceInternalUpdateVariable (
2008 DbName,
2009 &gEfiCertDbGuid,
2010 NewCertDb,
2011 NewCertDbSize,
2012 VarAttr
2013 );
2014
2015 return Status;
2016 }
2017
2018 /**
2019 Clean up signer's certificates for common authenticated variable
2020 by corresponding VariableName and VendorGuid from "certdb".
2021 System may break down during Timebased Variable update & certdb update,
2022 make them inconsistent, this function is called in AuthVariable Init
2023 to ensure consistency.
2024
2025 @retval EFI_NOT_FOUND Fail to find variable "certdb".
2026 @retval EFI_OUT_OF_RESOURCES The operation is failed due to lack of resources.
2027 @retval EFI_SUCCESS The operation is completed successfully.
2028
2029 **/
2030 EFI_STATUS
CleanCertsFromDb(VOID)2031 CleanCertsFromDb (
2032 VOID
2033 )
2034 {
2035 UINT32 Offset;
2036 AUTH_CERT_DB_DATA *Ptr;
2037 UINT32 NameSize;
2038 UINT32 NodeSize;
2039 CHAR16 *VariableName;
2040 EFI_STATUS Status;
2041 BOOLEAN CertCleaned;
2042 UINT8 *Data;
2043 UINTN DataSize;
2044 EFI_GUID AuthVarGuid;
2045 AUTH_VARIABLE_INFO AuthVariableInfo;
2046
2047 Status = EFI_SUCCESS;
2048
2049 //
2050 // Get corresponding certificates by VendorGuid and VariableName.
2051 //
2052 do {
2053 CertCleaned = FALSE;
2054
2055 //
2056 // Get latest variable "certdb"
2057 //
2058 Status = AuthServiceInternalFindVariable (
2059 EFI_CERT_DB_NAME,
2060 &gEfiCertDbGuid,
2061 (VOID **) &Data,
2062 &DataSize
2063 );
2064 if (EFI_ERROR (Status)) {
2065 return Status;
2066 }
2067
2068 if ((DataSize == 0) || (Data == NULL)) {
2069 ASSERT (FALSE);
2070 return EFI_NOT_FOUND;
2071 }
2072
2073 Offset = sizeof (UINT32);
2074
2075 while (Offset < (UINT32) DataSize) {
2076 Ptr = (AUTH_CERT_DB_DATA *) (Data + Offset);
2077 NodeSize = ReadUnaligned32 (&Ptr->CertNodeSize);
2078 NameSize = ReadUnaligned32 (&Ptr->NameSize);
2079
2080 //
2081 // Get VarName tailed with '\0'
2082 //
2083 VariableName = AllocateZeroPool((NameSize + 1) * sizeof(CHAR16));
2084 if (VariableName == NULL) {
2085 return EFI_OUT_OF_RESOURCES;
2086 }
2087 CopyMem (VariableName, (UINT8 *) Ptr + sizeof (AUTH_CERT_DB_DATA), NameSize * sizeof(CHAR16));
2088 //
2089 // Keep VarGuid aligned
2090 //
2091 CopyMem (&AuthVarGuid, &Ptr->VendorGuid, sizeof(EFI_GUID));
2092
2093 //
2094 // Find corresponding time auth variable
2095 //
2096 ZeroMem (&AuthVariableInfo, sizeof (AuthVariableInfo));
2097 Status = mAuthVarLibContextIn->FindVariable (
2098 VariableName,
2099 &AuthVarGuid,
2100 &AuthVariableInfo
2101 );
2102
2103 if (EFI_ERROR(Status) || (AuthVariableInfo.Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) == 0) {
2104 Status = DeleteCertsFromDb(
2105 VariableName,
2106 &AuthVarGuid,
2107 AuthVariableInfo.Attributes
2108 );
2109 CertCleaned = TRUE;
2110 DEBUG((EFI_D_INFO, "Recovery!! Cert for Auth Variable %s Guid %g is removed for consistency\n", VariableName, &AuthVarGuid));
2111 FreePool(VariableName);
2112 break;
2113 }
2114
2115 FreePool(VariableName);
2116 Offset = Offset + NodeSize;
2117 }
2118 } while (CertCleaned);
2119
2120 return Status;
2121 }
2122
2123 /**
2124 Process variable with EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS set
2125
2126 Caution: This function may receive untrusted input.
2127 This function may be invoked in SMM mode, and datasize and data are external input.
2128 This function will do basic validation, before parse the data.
2129 This function will parse the authentication carefully to avoid security issues, like
2130 buffer overflow, integer overflow.
2131
2132 @param[in] VariableName Name of Variable to be found.
2133 @param[in] VendorGuid Variable vendor GUID.
2134 @param[in] Data Data pointer.
2135 @param[in] DataSize Size of Data found. If size is less than the
2136 data, this value contains the required size.
2137 @param[in] Attributes Attribute value of the variable.
2138 @param[in] AuthVarType Verify against PK, KEK database, private database or certificate in data payload.
2139 @param[in] OrgTimeStamp Pointer to original time stamp,
2140 original variable is not found if NULL.
2141 @param[out] VarPayloadPtr Pointer to variable payload address.
2142 @param[out] VarPayloadSize Pointer to variable payload size.
2143
2144 @retval EFI_INVALID_PARAMETER Invalid parameter.
2145 @retval EFI_SECURITY_VIOLATION The variable does NOT pass the validation
2146 check carried out by the firmware.
2147 @retval EFI_OUT_OF_RESOURCES Failed to process variable due to lack
2148 of resources.
2149 @retval EFI_SUCCESS Variable pass validation successfully.
2150
2151 **/
2152 EFI_STATUS
VerifyTimeBasedPayload(IN CHAR16 * VariableName,IN EFI_GUID * VendorGuid,IN VOID * Data,IN UINTN DataSize,IN UINT32 Attributes,IN AUTHVAR_TYPE AuthVarType,IN EFI_TIME * OrgTimeStamp,OUT UINT8 ** VarPayloadPtr,OUT UINTN * VarPayloadSize)2153 VerifyTimeBasedPayload (
2154 IN CHAR16 *VariableName,
2155 IN EFI_GUID *VendorGuid,
2156 IN VOID *Data,
2157 IN UINTN DataSize,
2158 IN UINT32 Attributes,
2159 IN AUTHVAR_TYPE AuthVarType,
2160 IN EFI_TIME *OrgTimeStamp,
2161 OUT UINT8 **VarPayloadPtr,
2162 OUT UINTN *VarPayloadSize
2163 )
2164 {
2165 EFI_VARIABLE_AUTHENTICATION_2 *CertData;
2166 UINT8 *SigData;
2167 UINT32 SigDataSize;
2168 UINT8 *PayloadPtr;
2169 UINTN PayloadSize;
2170 UINT32 Attr;
2171 BOOLEAN VerifyStatus;
2172 EFI_STATUS Status;
2173 EFI_SIGNATURE_LIST *CertList;
2174 EFI_SIGNATURE_DATA *Cert;
2175 UINTN Index;
2176 UINTN CertCount;
2177 UINT32 KekDataSize;
2178 UINT8 *NewData;
2179 UINTN NewDataSize;
2180 UINT8 *Buffer;
2181 UINTN Length;
2182 UINT8 *RootCert;
2183 UINTN RootCertSize;
2184 UINT8 *SignerCerts;
2185 UINTN CertStackSize;
2186 UINT8 *CertsInCertDb;
2187 UINT32 CertsSizeinDb;
2188
2189 VerifyStatus = FALSE;
2190 CertData = NULL;
2191 NewData = NULL;
2192 Attr = Attributes;
2193 SignerCerts = NULL;
2194 RootCert = NULL;
2195 CertsInCertDb = NULL;
2196
2197 //
2198 // When the attribute EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS is
2199 // set, then the Data buffer shall begin with an instance of a complete (and serialized)
2200 // EFI_VARIABLE_AUTHENTICATION_2 descriptor. The descriptor shall be followed by the new
2201 // variable value and DataSize shall reflect the combined size of the descriptor and the new
2202 // variable value. The authentication descriptor is not part of the variable data and is not
2203 // returned by subsequent calls to GetVariable().
2204 //
2205 CertData = (EFI_VARIABLE_AUTHENTICATION_2 *) Data;
2206
2207 //
2208 // Verify that Pad1, Nanosecond, TimeZone, Daylight and Pad2 components of the
2209 // TimeStamp value are set to zero.
2210 //
2211 if ((CertData->TimeStamp.Pad1 != 0) ||
2212 (CertData->TimeStamp.Nanosecond != 0) ||
2213 (CertData->TimeStamp.TimeZone != 0) ||
2214 (CertData->TimeStamp.Daylight != 0) ||
2215 (CertData->TimeStamp.Pad2 != 0)) {
2216 return EFI_SECURITY_VIOLATION;
2217 }
2218
2219 if ((OrgTimeStamp != NULL) && ((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0)) {
2220 if (AuthServiceInternalCompareTimeStamp (&CertData->TimeStamp, OrgTimeStamp)) {
2221 //
2222 // TimeStamp check fail, suspicious replay attack, return EFI_SECURITY_VIOLATION.
2223 //
2224 return EFI_SECURITY_VIOLATION;
2225 }
2226 }
2227
2228 //
2229 // wCertificateType should be WIN_CERT_TYPE_EFI_GUID.
2230 // Cert type should be EFI_CERT_TYPE_PKCS7_GUID.
2231 //
2232 if ((CertData->AuthInfo.Hdr.wCertificateType != WIN_CERT_TYPE_EFI_GUID) ||
2233 !CompareGuid (&CertData->AuthInfo.CertType, &gEfiCertPkcs7Guid)) {
2234 //
2235 // Invalid AuthInfo type, return EFI_SECURITY_VIOLATION.
2236 //
2237 return EFI_SECURITY_VIOLATION;
2238 }
2239
2240 //
2241 // Find out Pkcs7 SignedData which follows the EFI_VARIABLE_AUTHENTICATION_2 descriptor.
2242 // AuthInfo.Hdr.dwLength is the length of the entire certificate, including the length of the header.
2243 //
2244 SigData = CertData->AuthInfo.CertData;
2245 SigDataSize = CertData->AuthInfo.Hdr.dwLength - (UINT32) (OFFSET_OF (WIN_CERTIFICATE_UEFI_GUID, CertData));
2246
2247 //
2248 // Find out the new data payload which follows Pkcs7 SignedData directly.
2249 //
2250 PayloadPtr = SigData + SigDataSize;
2251 PayloadSize = DataSize - OFFSET_OF_AUTHINFO2_CERT_DATA - (UINTN) SigDataSize;
2252
2253 //
2254 // Construct a serialization buffer of the values of the VariableName, VendorGuid and Attributes
2255 // parameters of the SetVariable() call and the TimeStamp component of the
2256 // EFI_VARIABLE_AUTHENTICATION_2 descriptor followed by the variable's new value
2257 // i.e. (VariableName, VendorGuid, Attributes, TimeStamp, Data)
2258 //
2259 NewDataSize = PayloadSize + sizeof (EFI_TIME) + sizeof (UINT32) +
2260 sizeof (EFI_GUID) + StrSize (VariableName) - sizeof (CHAR16);
2261
2262 //
2263 // Here is to reuse scratch data area(at the end of volatile variable store)
2264 // to reduce SMRAM consumption for SMM variable driver.
2265 // The scratch buffer is enough to hold the serialized data and safe to use,
2266 // because it is only used at here to do verification temporarily first
2267 // and then used in UpdateVariable() for a time based auth variable set.
2268 //
2269 Status = mAuthVarLibContextIn->GetScratchBuffer (&NewDataSize, (VOID **) &NewData);
2270 if (EFI_ERROR (Status)) {
2271 return EFI_OUT_OF_RESOURCES;
2272 }
2273
2274 Buffer = NewData;
2275 Length = StrLen (VariableName) * sizeof (CHAR16);
2276 CopyMem (Buffer, VariableName, Length);
2277 Buffer += Length;
2278
2279 Length = sizeof (EFI_GUID);
2280 CopyMem (Buffer, VendorGuid, Length);
2281 Buffer += Length;
2282
2283 Length = sizeof (UINT32);
2284 CopyMem (Buffer, &Attr, Length);
2285 Buffer += Length;
2286
2287 Length = sizeof (EFI_TIME);
2288 CopyMem (Buffer, &CertData->TimeStamp, Length);
2289 Buffer += Length;
2290
2291 CopyMem (Buffer, PayloadPtr, PayloadSize);
2292
2293 if (AuthVarType == AuthVarTypePk) {
2294 //
2295 // Verify that the signature has been made with the current Platform Key (no chaining for PK).
2296 // First, get signer's certificates from SignedData.
2297 //
2298 VerifyStatus = Pkcs7GetSigners (
2299 SigData,
2300 SigDataSize,
2301 &SignerCerts,
2302 &CertStackSize,
2303 &RootCert,
2304 &RootCertSize
2305 );
2306 if (!VerifyStatus) {
2307 goto Exit;
2308 }
2309
2310 //
2311 // Second, get the current platform key from variable. Check whether it's identical with signer's certificates
2312 // in SignedData. If not, return error immediately.
2313 //
2314 Status = AuthServiceInternalFindVariable (
2315 EFI_PLATFORM_KEY_NAME,
2316 &gEfiGlobalVariableGuid,
2317 &Data,
2318 &DataSize
2319 );
2320 if (EFI_ERROR (Status)) {
2321 VerifyStatus = FALSE;
2322 goto Exit;
2323 }
2324 CertList = (EFI_SIGNATURE_LIST *) Data;
2325 Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize);
2326 if ((RootCertSize != (CertList->SignatureSize - (sizeof (EFI_SIGNATURE_DATA) - 1))) ||
2327 (CompareMem (Cert->SignatureData, RootCert, RootCertSize) != 0)) {
2328 VerifyStatus = FALSE;
2329 goto Exit;
2330 }
2331
2332 //
2333 // Verify Pkcs7 SignedData via Pkcs7Verify library.
2334 //
2335 VerifyStatus = Pkcs7Verify (
2336 SigData,
2337 SigDataSize,
2338 RootCert,
2339 RootCertSize,
2340 NewData,
2341 NewDataSize
2342 );
2343
2344 } else if (AuthVarType == AuthVarTypeKek) {
2345
2346 //
2347 // Get KEK database from variable.
2348 //
2349 Status = AuthServiceInternalFindVariable (
2350 EFI_KEY_EXCHANGE_KEY_NAME,
2351 &gEfiGlobalVariableGuid,
2352 &Data,
2353 &DataSize
2354 );
2355 if (EFI_ERROR (Status)) {
2356 return Status;
2357 }
2358
2359 //
2360 // Ready to verify Pkcs7 SignedData. Go through KEK Signature Database to find out X.509 CertList.
2361 //
2362 KekDataSize = (UINT32) DataSize;
2363 CertList = (EFI_SIGNATURE_LIST *) Data;
2364 while ((KekDataSize > 0) && (KekDataSize >= CertList->SignatureListSize)) {
2365 if (CompareGuid (&CertList->SignatureType, &gEfiCertX509Guid)) {
2366 Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize);
2367 CertCount = (CertList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - CertList->SignatureHeaderSize) / CertList->SignatureSize;
2368 for (Index = 0; Index < CertCount; Index++) {
2369 //
2370 // Iterate each Signature Data Node within this CertList for a verify
2371 //
2372 RootCert = Cert->SignatureData;
2373 RootCertSize = CertList->SignatureSize - (sizeof (EFI_SIGNATURE_DATA) - 1);
2374
2375 //
2376 // Verify Pkcs7 SignedData via Pkcs7Verify library.
2377 //
2378 VerifyStatus = Pkcs7Verify (
2379 SigData,
2380 SigDataSize,
2381 RootCert,
2382 RootCertSize,
2383 NewData,
2384 NewDataSize
2385 );
2386 if (VerifyStatus) {
2387 goto Exit;
2388 }
2389 Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) Cert + CertList->SignatureSize);
2390 }
2391 }
2392 KekDataSize -= CertList->SignatureListSize;
2393 CertList = (EFI_SIGNATURE_LIST *) ((UINT8 *) CertList + CertList->SignatureListSize);
2394 }
2395 } else if (AuthVarType == AuthVarTypePriv) {
2396
2397 //
2398 // Process common authenticated variable except PK/KEK/DB/DBX/DBT.
2399 // Get signer's certificates from SignedData.
2400 //
2401 VerifyStatus = Pkcs7GetSigners (
2402 SigData,
2403 SigDataSize,
2404 &SignerCerts,
2405 &CertStackSize,
2406 &RootCert,
2407 &RootCertSize
2408 );
2409 if (!VerifyStatus) {
2410 goto Exit;
2411 }
2412
2413 //
2414 // Get previously stored signer's certificates from certdb or certdbv for existing
2415 // variable. Check whether they are identical with signer's certificates
2416 // in SignedData. If not, return error immediately.
2417 //
2418 if (OrgTimeStamp != NULL) {
2419 VerifyStatus = FALSE;
2420
2421 Status = GetCertsFromDb (VariableName, VendorGuid, Attributes, &CertsInCertDb, &CertsSizeinDb);
2422 if (EFI_ERROR (Status)) {
2423 goto Exit;
2424 }
2425
2426 if ((CertStackSize != CertsSizeinDb) ||
2427 (CompareMem (SignerCerts, CertsInCertDb, CertsSizeinDb) != 0)) {
2428 goto Exit;
2429 }
2430 }
2431
2432 VerifyStatus = Pkcs7Verify (
2433 SigData,
2434 SigDataSize,
2435 RootCert,
2436 RootCertSize,
2437 NewData,
2438 NewDataSize
2439 );
2440 if (!VerifyStatus) {
2441 goto Exit;
2442 }
2443
2444 if ((OrgTimeStamp == NULL) && (PayloadSize != 0)) {
2445 //
2446 // Insert signer's certificates when adding a new common authenticated variable.
2447 //
2448 Status = InsertCertsToDb (VariableName, VendorGuid, Attributes, SignerCerts, CertStackSize);
2449 if (EFI_ERROR (Status)) {
2450 VerifyStatus = FALSE;
2451 goto Exit;
2452 }
2453 }
2454 } else if (AuthVarType == AuthVarTypePayload) {
2455 CertList = (EFI_SIGNATURE_LIST *) PayloadPtr;
2456 Cert = (EFI_SIGNATURE_DATA *) ((UINT8 *) CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize);
2457 RootCert = Cert->SignatureData;
2458 RootCertSize = CertList->SignatureSize - (sizeof (EFI_SIGNATURE_DATA) - 1);
2459 //
2460 // Verify Pkcs7 SignedData via Pkcs7Verify library.
2461 //
2462 VerifyStatus = Pkcs7Verify (
2463 SigData,
2464 SigDataSize,
2465 RootCert,
2466 RootCertSize,
2467 NewData,
2468 NewDataSize
2469 );
2470 } else {
2471 return EFI_SECURITY_VIOLATION;
2472 }
2473
2474 Exit:
2475
2476 if (AuthVarType == AuthVarTypePk || AuthVarType == AuthVarTypePriv) {
2477 Pkcs7FreeSigners (RootCert);
2478 Pkcs7FreeSigners (SignerCerts);
2479 }
2480
2481 if (!VerifyStatus) {
2482 return EFI_SECURITY_VIOLATION;
2483 }
2484
2485 Status = CheckSignatureListFormat(VariableName, VendorGuid, PayloadPtr, PayloadSize);
2486 if (EFI_ERROR (Status)) {
2487 return Status;
2488 }
2489
2490 *VarPayloadPtr = PayloadPtr;
2491 *VarPayloadSize = PayloadSize;
2492
2493 return EFI_SUCCESS;
2494 }
2495
2496 /**
2497 Process variable with EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS set
2498
2499 Caution: This function may receive untrusted input.
2500 This function may be invoked in SMM mode, and datasize and data are external input.
2501 This function will do basic validation, before parse the data.
2502 This function will parse the authentication carefully to avoid security issues, like
2503 buffer overflow, integer overflow.
2504
2505 @param[in] VariableName Name of Variable to be found.
2506 @param[in] VendorGuid Variable vendor GUID.
2507 @param[in] Data Data pointer.
2508 @param[in] DataSize Size of Data found. If size is less than the
2509 data, this value contains the required size.
2510 @param[in] Attributes Attribute value of the variable.
2511 @param[in] AuthVarType Verify against PK, KEK database, private database or certificate in data payload.
2512 @param[out] VarDel Delete the variable or not.
2513
2514 @retval EFI_INVALID_PARAMETER Invalid parameter.
2515 @retval EFI_SECURITY_VIOLATION The variable does NOT pass the validation
2516 check carried out by the firmware.
2517 @retval EFI_OUT_OF_RESOURCES Failed to process variable due to lack
2518 of resources.
2519 @retval EFI_SUCCESS Variable pass validation successfully.
2520
2521 **/
2522 EFI_STATUS
VerifyTimeBasedPayloadAndUpdate(IN CHAR16 * VariableName,IN EFI_GUID * VendorGuid,IN VOID * Data,IN UINTN DataSize,IN UINT32 Attributes,IN AUTHVAR_TYPE AuthVarType,OUT BOOLEAN * VarDel)2523 VerifyTimeBasedPayloadAndUpdate (
2524 IN CHAR16 *VariableName,
2525 IN EFI_GUID *VendorGuid,
2526 IN VOID *Data,
2527 IN UINTN DataSize,
2528 IN UINT32 Attributes,
2529 IN AUTHVAR_TYPE AuthVarType,
2530 OUT BOOLEAN *VarDel
2531 )
2532 {
2533 EFI_STATUS Status;
2534 EFI_STATUS FindStatus;
2535 UINT8 *PayloadPtr;
2536 UINTN PayloadSize;
2537 EFI_VARIABLE_AUTHENTICATION_2 *CertData;
2538 AUTH_VARIABLE_INFO OrgVariableInfo;
2539 BOOLEAN IsDel;
2540
2541 ZeroMem (&OrgVariableInfo, sizeof (OrgVariableInfo));
2542 FindStatus = mAuthVarLibContextIn->FindVariable (
2543 VariableName,
2544 VendorGuid,
2545 &OrgVariableInfo
2546 );
2547
2548 Status = VerifyTimeBasedPayload (
2549 VariableName,
2550 VendorGuid,
2551 Data,
2552 DataSize,
2553 Attributes,
2554 AuthVarType,
2555 (!EFI_ERROR (FindStatus)) ? OrgVariableInfo.TimeStamp : NULL,
2556 &PayloadPtr,
2557 &PayloadSize
2558 );
2559 if (EFI_ERROR (Status)) {
2560 return Status;
2561 }
2562
2563 if (!EFI_ERROR(FindStatus)
2564 && (PayloadSize == 0)
2565 && ((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0)) {
2566 IsDel = TRUE;
2567 } else {
2568 IsDel = FALSE;
2569 }
2570
2571 CertData = (EFI_VARIABLE_AUTHENTICATION_2 *) Data;
2572
2573 //
2574 // Final step: Update/Append Variable if it pass Pkcs7Verify
2575 //
2576 Status = AuthServiceInternalUpdateVariableWithTimeStamp (
2577 VariableName,
2578 VendorGuid,
2579 PayloadPtr,
2580 PayloadSize,
2581 Attributes,
2582 &CertData->TimeStamp
2583 );
2584
2585 //
2586 // Delete signer's certificates when delete the common authenticated variable.
2587 //
2588 if (IsDel && AuthVarType == AuthVarTypePriv && !EFI_ERROR(Status) ) {
2589 Status = DeleteCertsFromDb (VariableName, VendorGuid, Attributes);
2590 }
2591
2592 if (VarDel != NULL) {
2593 if (IsDel && !EFI_ERROR(Status)) {
2594 *VarDel = TRUE;
2595 } else {
2596 *VarDel = FALSE;
2597 }
2598 }
2599
2600 return Status;
2601 }
2602