]> git.proxmox.com Git - mirror_edk2.git/blob - SecurityPkg/Library/AuthVariableLib/AuthService.c
projects / mirror_edk2.git / blob
? search:


054ee4d1d9886a0f05a3cac43dd2a87728c6f47a
[mirror_edk2.git] / SecurityPkg / Library / AuthVariableLib / AuthService.c
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 - 2019, Intel Corporation. All rights reserved.<BR>
22 Copyright (c) Microsoft Corporation.
23 SPDX-License-Identifier: BSD-2-Clause-Patent
24
25 **/
26
27 #include "AuthServiceInternal.h"
28
29 #include <Protocol/VariablePolicy.h>
30 #include <Library/VariablePolicyLib.h>
31
32 //
33 // Public Exponent of RSA Key.
34 //
35 CONST UINT8 mRsaE[] = { 0x01, 0x00, 0x01 };
36
37 CONST UINT8 mSha256OidValue[] = { 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 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
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
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] TimeStamp Value of associated TimeStamp.
146
147 @retval EFI_SUCCESS The update operation is success.
148 @retval EFI_INVALID_PARAMETER Invalid parameter.
149 @retval EFI_WRITE_PROTECTED Variable is write-protected.
150 @retval EFI_OUT_OF_RESOURCES There is not enough resource.
151
152 **/
153 EFI_STATUS
154 AuthServiceInternalUpdateVariableWithTimeStamp (
155 IN CHAR16 *VariableName,
156 IN EFI_GUID *VendorGuid,
157 IN VOID *Data,
158 IN UINTN DataSize,
159 IN UINT32 Attributes,
160 IN EFI_TIME *TimeStamp
161 )
162 {
163 EFI_STATUS FindStatus;
164 VOID *OrgData;
165 UINTN OrgDataSize;
166 AUTH_VARIABLE_INFO AuthVariableInfo;
167
168 FindStatus = AuthServiceInternalFindVariable (
169 VariableName,
170 VendorGuid,
171 &OrgData,
172 &OrgDataSize
173 );
174
175 //
176 // EFI_VARIABLE_APPEND_WRITE attribute only effects for existing variable
177 //
178 if (!EFI_ERROR (FindStatus) && ((Attributes & EFI_VARIABLE_APPEND_WRITE) != 0)) {
179 if ((CompareGuid (VendorGuid, &gEfiImageSecurityDatabaseGuid) &&
180 ((StrCmp (VariableName, EFI_IMAGE_SECURITY_DATABASE) == 0) || (StrCmp (VariableName, EFI_IMAGE_SECURITY_DATABASE1) == 0) ||
181 (StrCmp (VariableName, EFI_IMAGE_SECURITY_DATABASE2) == 0))) ||
182 (CompareGuid (VendorGuid, &gEfiGlobalVariableGuid) && (StrCmp (VariableName, EFI_KEY_EXCHANGE_KEY_NAME) == 0)))
183 {
184 //
185 // For variables with formatted as EFI_SIGNATURE_LIST, the driver shall not perform an append of
186 // EFI_SIGNATURE_DATA values that are already part of the existing variable value.
187 //
188 FilterSignatureList (
189 OrgData,
190 OrgDataSize,
191 Data,
192 &DataSize
193 );
194 }
195 }
196
197 ZeroMem (&AuthVariableInfo, sizeof (AuthVariableInfo));
198 AuthVariableInfo.VariableName = VariableName;
199 AuthVariableInfo.VendorGuid = VendorGuid;
200 AuthVariableInfo.Data = Data;
201 AuthVariableInfo.DataSize = DataSize;
202 AuthVariableInfo.Attributes = Attributes;
203 AuthVariableInfo.TimeStamp = TimeStamp;
204 return mAuthVarLibContextIn->UpdateVariable (
205 &AuthVariableInfo
206 );
207 }
208
209 /**
210 Determine whether this operation needs a physical present user.
211
212 @param[in] VariableName Name of the Variable.
213 @param[in] VendorGuid GUID of the Variable.
214
215 @retval TRUE This variable is protected, only a physical present user could set this variable.
216 @retval FALSE This variable is not protected.
217
218 **/
219 BOOLEAN
220 NeedPhysicallyPresent (
221 IN CHAR16 *VariableName,
222 IN EFI_GUID *VendorGuid
223 )
224 {
225 // If the VariablePolicy engine is disabled, allow deletion of any authenticated variables.
226 if (IsVariablePolicyEnabled ()) {
227 if ( (CompareGuid (VendorGuid, &gEfiSecureBootEnableDisableGuid) && (StrCmp (VariableName, EFI_SECURE_BOOT_ENABLE_NAME) == 0))
228 || (CompareGuid (VendorGuid, &gEfiCustomModeEnableGuid) && (StrCmp (VariableName, EFI_CUSTOM_MODE_NAME) == 0)))
229 {
230 return TRUE;
231 }
232 }
233
234 return FALSE;
235 }
236
237 /**
238 Determine whether the platform is operating in Custom Secure Boot mode.
239
240 @retval TRUE The platform is operating in Custom mode.
241 @retval FALSE The platform is operating in Standard mode.
242
243 **/
244 BOOLEAN
245 InCustomMode (
246 VOID
247 )
248 {
249 EFI_STATUS Status;
250 VOID *Data;
251 UINTN DataSize;
252
253 Status = AuthServiceInternalFindVariable (EFI_CUSTOM_MODE_NAME, &gEfiCustomModeEnableGuid, &Data, &DataSize);
254 if (!EFI_ERROR (Status) && (*(UINT8 *)Data == CUSTOM_SECURE_BOOT_MODE)) {
255 return TRUE;
256 }
257
258 return FALSE;
259 }
260
261 /**
262 Update platform mode.
263
264 @param[in] Mode SETUP_MODE or USER_MODE.
265
266 @return EFI_INVALID_PARAMETER Invalid parameter.
267 @return EFI_SUCCESS Update platform mode successfully.
268
269 **/
270 EFI_STATUS
271 UpdatePlatformMode (
272 IN UINT32 Mode
273 )
274 {
275 EFI_STATUS Status;
276 VOID *Data;
277 UINTN DataSize;
278 UINT8 SecureBootMode;
279 UINT8 SecureBootEnable;
280 UINTN VariableDataSize;
281
282 Status = AuthServiceInternalFindVariable (
283 EFI_SETUP_MODE_NAME,
284 &gEfiGlobalVariableGuid,
285 &Data,
286 &DataSize
287 );
288 if (EFI_ERROR (Status)) {
289 return Status;
290 }
291
292 //
293 // Update the value of SetupMode variable by a simple mem copy, this could avoid possible
294 // variable storage reclaim at runtime.
295 //
296 mPlatformMode = (UINT8)Mode;
297 CopyMem (Data, &mPlatformMode, sizeof (UINT8));
298
299 if (mAuthVarLibContextIn->AtRuntime ()) {
300 //
301 // SecureBoot Variable indicates whether the platform firmware is operating
302 // in Secure boot mode (1) or not (0), so we should not change SecureBoot
303 // Variable in runtime.
304 //
305 return Status;
306 }
307
308 //
309 // Check "SecureBoot" variable's existence.
310 // If it doesn't exist, firmware has no capability to perform driver signing verification,
311 // then set "SecureBoot" to 0.
312 //
313 Status = AuthServiceInternalFindVariable (
314 EFI_SECURE_BOOT_MODE_NAME,
315 &gEfiGlobalVariableGuid,
316 &Data,
317 &DataSize
318 );
319 //
320 // If "SecureBoot" variable exists, then check "SetupMode" variable update.
321 // If "SetupMode" variable is USER_MODE, "SecureBoot" variable is set to 1.
322 // If "SetupMode" variable is SETUP_MODE, "SecureBoot" variable is set to 0.
323 //
324 if (EFI_ERROR (Status)) {
325 SecureBootMode = SECURE_BOOT_MODE_DISABLE;
326 } else {
327 if (mPlatformMode == USER_MODE) {
328 SecureBootMode = SECURE_BOOT_MODE_ENABLE;
329 } else if (mPlatformMode == SETUP_MODE) {
330 SecureBootMode = SECURE_BOOT_MODE_DISABLE;
331 } else {
332 return EFI_NOT_FOUND;
333 }
334 }
335
336 Status = AuthServiceInternalUpdateVariable (
337 EFI_SECURE_BOOT_MODE_NAME,
338 &gEfiGlobalVariableGuid,
339 &SecureBootMode,
340 sizeof (UINT8),
341 EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS
342 );
343 if (EFI_ERROR (Status)) {
344 return Status;
345 }
346
347 //
348 // Check "SecureBootEnable" variable's existence. It can enable/disable secure boot feature.
349 //
350 Status = AuthServiceInternalFindVariable (
351 EFI_SECURE_BOOT_ENABLE_NAME,
352 &gEfiSecureBootEnableDisableGuid,
353 &Data,
354 &DataSize
355 );
356
357 if (SecureBootMode == SECURE_BOOT_MODE_ENABLE) {
358 //
359 // Create the "SecureBootEnable" variable as secure boot is enabled.
360 //
361 SecureBootEnable = SECURE_BOOT_ENABLE;
362 VariableDataSize = sizeof (SecureBootEnable);
363 } else {
364 //
365 // Delete the "SecureBootEnable" variable if this variable exist as "SecureBoot"
366 // variable is not in secure boot state.
367 //
368 if (EFI_ERROR (Status)) {
369 return EFI_SUCCESS;
370 }
371
372 SecureBootEnable = SECURE_BOOT_DISABLE;
373 VariableDataSize = 0;
374 }
375
376 Status = AuthServiceInternalUpdateVariable (
377 EFI_SECURE_BOOT_ENABLE_NAME,
378 &gEfiSecureBootEnableDisableGuid,
379 &SecureBootEnable,
380 VariableDataSize,
381 EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS
382 );
383 return Status;
384 }
385
386 /**
387 Check input data form to make sure it is a valid EFI_SIGNATURE_LIST for PK/KEK/db/dbx/dbt variable.
388
389 @param[in] VariableName Name of Variable to be check.
390 @param[in] VendorGuid Variable vendor GUID.
391 @param[in] Data Point to the variable data to be checked.
392 @param[in] DataSize Size of Data.
393
394 @return EFI_INVALID_PARAMETER Invalid signature list format.
395 @return EFI_SUCCESS Passed signature list format check successfully.
396
397 **/
398 EFI_STATUS
399 CheckSignatureListFormat (
400 IN CHAR16 *VariableName,
401 IN EFI_GUID *VendorGuid,
402 IN VOID *Data,
403 IN UINTN DataSize
404 )
405 {
406 EFI_SIGNATURE_LIST *SigList;
407 UINTN SigDataSize;
408 UINT32 Index;
409 UINT32 SigCount;
410 BOOLEAN IsPk;
411 VOID *RsaContext;
412 EFI_SIGNATURE_DATA *CertData;
413 UINTN CertLen;
414
415 if (DataSize == 0) {
416 return EFI_SUCCESS;
417 }
418
419 ASSERT (VariableName != NULL && VendorGuid != NULL && Data != NULL);
420
421 if (CompareGuid (VendorGuid, &gEfiGlobalVariableGuid) && (StrCmp (VariableName, EFI_PLATFORM_KEY_NAME) == 0)) {
422 IsPk = TRUE;
423 } else if ((CompareGuid (VendorGuid, &gEfiGlobalVariableGuid) && (StrCmp (VariableName, EFI_KEY_EXCHANGE_KEY_NAME) == 0)) ||
424 (CompareGuid (VendorGuid, &gEfiImageSecurityDatabaseGuid) &&
425 ((StrCmp (VariableName, EFI_IMAGE_SECURITY_DATABASE) == 0) || (StrCmp (VariableName, EFI_IMAGE_SECURITY_DATABASE1) == 0) ||
426 (StrCmp (VariableName, EFI_IMAGE_SECURITY_DATABASE2) == 0))))
427 {
428 IsPk = FALSE;
429 } else {
430 return EFI_SUCCESS;
431 }
432
433 SigCount = 0;
434 SigList = (EFI_SIGNATURE_LIST *)Data;
435 SigDataSize = DataSize;
436 RsaContext = NULL;
437
438 //
439 // Walk through the input signature list and check the data format.
440 // If any signature is incorrectly formed, the whole check will fail.
441 //
442 while ((SigDataSize > 0) && (SigDataSize >= SigList->SignatureListSize)) {
443 for (Index = 0; Index < (sizeof (mSupportSigItem) / sizeof (EFI_SIGNATURE_ITEM)); Index++ ) {
444 if (CompareGuid (&SigList->SignatureType, &mSupportSigItem[Index].SigType)) {
445 //
446 // The value of SignatureSize should always be 16 (size of SignatureOwner
447 // component) add the data length according to signature type.
448 //
449 if ((mSupportSigItem[Index].SigDataSize != ((UINT32) ~0)) &&
450 ((SigList->SignatureSize - sizeof (EFI_GUID)) != mSupportSigItem[Index].SigDataSize))
451 {
452 return EFI_INVALID_PARAMETER;
453 }
454
455 if ((mSupportSigItem[Index].SigHeaderSize != ((UINT32) ~0)) &&
456 (SigList->SignatureHeaderSize != mSupportSigItem[Index].SigHeaderSize))
457 {
458 return EFI_INVALID_PARAMETER;
459 }
460
461 break;
462 }
463 }
464
465 if (Index == (sizeof (mSupportSigItem) / sizeof (EFI_SIGNATURE_ITEM))) {
466 //
467 // Undefined signature type.
468 //
469 return EFI_INVALID_PARAMETER;
470 }
471
472 if (CompareGuid (&SigList->SignatureType, &gEfiCertX509Guid)) {
473 //
474 // Try to retrieve the RSA public key from the X.509 certificate.
475 // If this operation fails, it's not a valid certificate.
476 //
477 RsaContext = RsaNew ();
478 if (RsaContext == NULL) {
479 return EFI_INVALID_PARAMETER;
480 }
481
482 CertData = (EFI_SIGNATURE_DATA *)((UINT8 *)SigList + sizeof (EFI_SIGNATURE_LIST) + SigList->SignatureHeaderSize);
483 CertLen = SigList->SignatureSize - sizeof (EFI_GUID);
484 if (!RsaGetPublicKeyFromX509 (CertData->SignatureData, CertLen, &RsaContext)) {
485 RsaFree (RsaContext);
486 return EFI_INVALID_PARAMETER;
487 }
488
489 RsaFree (RsaContext);
490 }
491
492 if ((SigList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - SigList->SignatureHeaderSize) % SigList->SignatureSize != 0) {
493 return EFI_INVALID_PARAMETER;
494 }
495
496 SigCount += (SigList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - SigList->SignatureHeaderSize) / SigList->SignatureSize;
497
498 SigDataSize -= SigList->SignatureListSize;
499 SigList = (EFI_SIGNATURE_LIST *)((UINT8 *)SigList + SigList->SignatureListSize);
500 }
501
502 if (((UINTN)SigList - (UINTN)Data) != DataSize) {
503 return EFI_INVALID_PARAMETER;
504 }
505
506 if (IsPk && (SigCount > 1)) {
507 return EFI_INVALID_PARAMETER;
508 }
509
510 return EFI_SUCCESS;
511 }
512
513 /**
514 Update "VendorKeys" variable to record the out of band secure boot key modification.
515
516 @return EFI_SUCCESS Variable is updated successfully.
517 @return Others Failed to update variable.
518
519 **/
520 EFI_STATUS
521 VendorKeyIsModified (
522 VOID
523 )
524 {
525 EFI_STATUS Status;
526
527 if (mVendorKeyState == VENDOR_KEYS_MODIFIED) {
528 return EFI_SUCCESS;
529 }
530
531 mVendorKeyState = VENDOR_KEYS_MODIFIED;
532
533 Status = AuthServiceInternalUpdateVariable (
534 EFI_VENDOR_KEYS_NV_VARIABLE_NAME,
535 &gEfiVendorKeysNvGuid,
536 &mVendorKeyState,
537 sizeof (UINT8),
538 EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS
539 );
540 if (EFI_ERROR (Status)) {
541 return Status;
542 }
543
544 return AuthServiceInternalUpdateVariable (
545 EFI_VENDOR_KEYS_VARIABLE_NAME,
546 &gEfiGlobalVariableGuid,
547 &mVendorKeyState,
548 sizeof (UINT8),
549 EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS
550 );
551 }
552
553 /**
554 Process variable with platform key for verification.
555
556 Caution: This function may receive untrusted input.
557 This function may be invoked in SMM mode, and datasize and data are external input.
558 This function will do basic validation, before parse the data.
559 This function will parse the authentication carefully to avoid security issues, like
560 buffer overflow, integer overflow.
561 This function will check attribute carefully to avoid authentication bypass.
562
563 @param[in] VariableName Name of Variable to be found.
564 @param[in] VendorGuid Variable vendor GUID.
565 @param[in] Data Data pointer.
566 @param[in] DataSize Size of Data found. If size is less than the
567 data, this value contains the required size.
568 @param[in] Attributes Attribute value of the variable
569 @param[in] IsPk Indicate whether it is to process pk.
570
571 @return EFI_INVALID_PARAMETER Invalid parameter.
572 @return EFI_SECURITY_VIOLATION The variable does NOT pass the validation.
573 check carried out by the firmware.
574 @return EFI_SUCCESS Variable passed validation successfully.
575
576 **/
577 EFI_STATUS
578 ProcessVarWithPk (
579 IN CHAR16 *VariableName,
580 IN EFI_GUID *VendorGuid,
581 IN VOID *Data,
582 IN UINTN DataSize,
583 IN UINT32 Attributes OPTIONAL,
584 IN BOOLEAN IsPk
585 )
586 {
587 EFI_STATUS Status;
588 BOOLEAN Del;
589 UINT8 *Payload;
590 UINTN PayloadSize;
591
592 if (((Attributes & EFI_VARIABLE_NON_VOLATILE) == 0) ||
593 ((Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) == 0))
594 {
595 //
596 // PK, KEK and db/dbx/dbt should set EFI_VARIABLE_NON_VOLATILE attribute and should be a time-based
597 // authenticated variable.
598 //
599 return EFI_INVALID_PARAMETER;
600 }
601
602 //
603 // Init state of Del. State may change due to secure check
604 //
605 Del = FALSE;
606 if ((InCustomMode () && UserPhysicalPresent ()) || ((mPlatformMode == SETUP_MODE) && !IsPk)) {
607 Payload = (UINT8 *)Data + AUTHINFO2_SIZE (Data);
608 PayloadSize = DataSize - AUTHINFO2_SIZE (Data);
609 if (PayloadSize == 0) {
610 Del = TRUE;
611 }
612
613 Status = CheckSignatureListFormat (VariableName, VendorGuid, Payload, PayloadSize);
614 if (EFI_ERROR (Status)) {
615 return Status;
616 }
617
618 Status = AuthServiceInternalUpdateVariableWithTimeStamp (
619 VariableName,
620 VendorGuid,
621 Payload,
622 PayloadSize,
623 Attributes,
624 &((EFI_VARIABLE_AUTHENTICATION_2 *)Data)->TimeStamp
625 );
626 if (EFI_ERROR (Status)) {
627 return Status;
628 }
629
630 if ((mPlatformMode != SETUP_MODE) || IsPk) {
631 Status = VendorKeyIsModified ();
632 }
633 } else if (mPlatformMode == USER_MODE) {
634 //
635 // Verify against X509 Cert in PK database.
636 //
637 Status = VerifyTimeBasedPayloadAndUpdate (
638 VariableName,
639 VendorGuid,
640 Data,
641 DataSize,
642 Attributes,
643 AuthVarTypePk,
644 &Del
645 );
646 } else {
647 //
648 // Verify against the certificate in data payload.
649 //
650 Status = VerifyTimeBasedPayloadAndUpdate (
651 VariableName,
652 VendorGuid,
653 Data,
654 DataSize,
655 Attributes,
656 AuthVarTypePayload,
657 &Del
658 );
659 }
660
661 if (!EFI_ERROR (Status) && IsPk) {
662 if ((mPlatformMode == SETUP_MODE) && !Del) {
663 //
664 // If enroll PK in setup mode, need change to user mode.
665 //
666 Status = UpdatePlatformMode (USER_MODE);
667 } else if ((mPlatformMode == USER_MODE) && Del) {
668 //
669 // If delete PK in user mode, need change to setup mode.
670 //
671 Status = UpdatePlatformMode (SETUP_MODE);
672 }
673 }
674
675 return Status;
676 }
677
678 /**
679 Process variable with key exchange key for verification.
680
681 Caution: This function may receive untrusted input.
682 This function may be invoked in SMM mode, and datasize and data are external input.
683 This function will do basic validation, before parse the data.
684 This function will parse the authentication carefully to avoid security issues, like
685 buffer overflow, integer overflow.
686 This function will check attribute carefully to avoid authentication bypass.
687
688 @param[in] VariableName Name of Variable to be found.
689 @param[in] VendorGuid Variable vendor GUID.
690 @param[in] Data Data pointer.
691 @param[in] DataSize Size of Data found. If size is less than the
692 data, this value contains the required size.
693 @param[in] Attributes Attribute value of the variable.
694
695 @return EFI_INVALID_PARAMETER Invalid parameter.
696 @return EFI_SECURITY_VIOLATION The variable does NOT pass the validation
697 check carried out by the firmware.
698 @return EFI_SUCCESS Variable pass validation successfully.
699
700 **/
701 EFI_STATUS
702 ProcessVarWithKek (
703 IN CHAR16 *VariableName,
704 IN EFI_GUID *VendorGuid,
705 IN VOID *Data,
706 IN UINTN DataSize,
707 IN UINT32 Attributes OPTIONAL
708 )
709 {
710 EFI_STATUS Status;
711 UINT8 *Payload;
712 UINTN PayloadSize;
713
714 if (((Attributes & EFI_VARIABLE_NON_VOLATILE) == 0) ||
715 ((Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) == 0))
716 {
717 //
718 // DB, DBX and DBT should set EFI_VARIABLE_NON_VOLATILE attribute and should be a time-based
719 // authenticated variable.
720 //
721 return EFI_INVALID_PARAMETER;
722 }
723
724 Status = EFI_SUCCESS;
725 if ((mPlatformMode == USER_MODE) && !(InCustomMode () && UserPhysicalPresent ())) {
726 //
727 // Time-based, verify against X509 Cert KEK.
728 //
729 return VerifyTimeBasedPayloadAndUpdate (
730 VariableName,
731 VendorGuid,
732 Data,
733 DataSize,
734 Attributes,
735 AuthVarTypeKek,
736 NULL
737 );
738 } else {
739 //
740 // If in setup mode or custom secure boot mode, no authentication needed.
741 //
742 Payload = (UINT8 *)Data + AUTHINFO2_SIZE (Data);
743 PayloadSize = DataSize - AUTHINFO2_SIZE (Data);
744
745 Status = CheckSignatureListFormat (VariableName, VendorGuid, Payload, PayloadSize);
746 if (EFI_ERROR (Status)) {
747 return Status;
748 }
749
750 Status = AuthServiceInternalUpdateVariableWithTimeStamp (
751 VariableName,
752 VendorGuid,
753 Payload,
754 PayloadSize,
755 Attributes,
756 &((EFI_VARIABLE_AUTHENTICATION_2 *)Data)->TimeStamp
757 );
758 if (EFI_ERROR (Status)) {
759 return Status;
760 }
761
762 if (mPlatformMode != SETUP_MODE) {
763 Status = VendorKeyIsModified ();
764 }
765 }
766
767 return Status;
768 }
769
770 /**
771 Check if it is to delete auth variable.
772
773 @param[in] OrgAttributes Original attribute value of the variable.
774 @param[in] Data Data pointer.
775 @param[in] DataSize Size of Data.
776 @param[in] Attributes Attribute value of the variable.
777
778 @retval TRUE It is to delete auth variable.
779 @retval FALSE It is not to delete auth variable.
780
781 **/
782 BOOLEAN
783 IsDeleteAuthVariable (
784 IN UINT32 OrgAttributes,
785 IN VOID *Data,
786 IN UINTN DataSize,
787 IN UINT32 Attributes
788 )
789 {
790 BOOLEAN Del;
791 UINTN PayloadSize;
792
793 Del = FALSE;
794
795 //
796 // To delete a variable created with the EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS
797 // or the EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS attribute,
798 // SetVariable must be used with attributes matching the existing variable
799 // and the DataSize set to the size of the AuthInfo descriptor.
800 //
801 if ((Attributes == OrgAttributes) &&
802 ((Attributes & (EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS)) != 0))
803 {
804 if ((Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) != 0) {
805 PayloadSize = DataSize - AUTHINFO2_SIZE (Data);
806 if (PayloadSize == 0) {
807 Del = TRUE;
808 }
809 } else {
810 PayloadSize = DataSize - AUTHINFO_SIZE;
811 if (PayloadSize == 0) {
812 Del = TRUE;
813 }
814 }
815 }
816
817 return Del;
818 }
819
820 /**
821 Process variable with EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS set
822
823 Caution: This function may receive untrusted input.
824 This function may be invoked in SMM mode, and datasize and data are external input.
825 This function will do basic validation, before parse the data.
826 This function will parse the authentication carefully to avoid security issues, like
827 buffer overflow, integer overflow.
828 This function will check attribute carefully to avoid authentication bypass.
829
830 @param[in] VariableName Name of the variable.
831 @param[in] VendorGuid Variable vendor GUID.
832 @param[in] Data Data pointer.
833 @param[in] DataSize Size of Data.
834 @param[in] Attributes Attribute value of the variable.
835
836 @return EFI_INVALID_PARAMETER Invalid parameter.
837 @return EFI_WRITE_PROTECTED Variable is write-protected and needs authentication with
838 EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS or EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS set.
839 @return EFI_OUT_OF_RESOURCES The Database to save the public key is full.
840 @return EFI_SECURITY_VIOLATION The variable is with EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS
841 set, but the AuthInfo does NOT pass the validation
842 check carried out by the firmware.
843 @return EFI_SUCCESS Variable is not write-protected or pass validation successfully.
844
845 **/
846 EFI_STATUS
847 ProcessVariable (
848 IN CHAR16 *VariableName,
849 IN EFI_GUID *VendorGuid,
850 IN VOID *Data,
851 IN UINTN DataSize,
852 IN UINT32 Attributes
853 )
854 {
855 EFI_STATUS Status;
856 AUTH_VARIABLE_INFO OrgVariableInfo;
857
858 Status = EFI_SUCCESS;
859
860 ZeroMem (&OrgVariableInfo, sizeof (OrgVariableInfo));
861 Status = mAuthVarLibContextIn->FindVariable (
862 VariableName,
863 VendorGuid,
864 &OrgVariableInfo
865 );
866
867 // If the VariablePolicy engine is disabled, allow deletion of any authenticated variables.
868 if ((!EFI_ERROR (Status)) && IsDeleteAuthVariable (OrgVariableInfo.Attributes, Data, DataSize, Attributes) && (UserPhysicalPresent () || !IsVariablePolicyEnabled ())) {
869 //
870 // Allow the delete operation of common authenticated variable(AT or AW) at user physical presence.
871 //
872 Status = AuthServiceInternalUpdateVariable (
873 VariableName,
874 VendorGuid,
875 NULL,
876 0,
877 0
878 );
879 if (!EFI_ERROR (Status) && ((Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) != 0)) {
880 Status = DeleteCertsFromDb (VariableName, VendorGuid, Attributes);
881 }
882
883 return Status;
884 }
885
886 if (NeedPhysicallyPresent (VariableName, VendorGuid) && !UserPhysicalPresent ()) {
887 //
888 // This variable is protected, only physical present user could modify its value.
889 //
890 return EFI_SECURITY_VIOLATION;
891 }
892
893 //
894 if ((Attributes & EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS) != 0) {
895 //
896 // Reject Counter Based Auth Variable processing request.
897 //
898 return EFI_UNSUPPORTED;
899 } else if ((Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) != 0) {
900 //
901 // Process Time-based Authenticated variable.
902 //
903 return VerifyTimeBasedPayloadAndUpdate (
904 VariableName,
905 VendorGuid,
906 Data,
907 DataSize,
908 Attributes,
909 AuthVarTypePriv,
910 NULL
911 );
912 }
913
914 if ((OrgVariableInfo.Data != NULL) &&
915 ((OrgVariableInfo.Attributes & (EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS)) != 0))
916 {
917 //
918 // If the variable is already write-protected, it always needs authentication before update.
919 //
920 return EFI_WRITE_PROTECTED;
921 }
922
923 //
924 // Not authenticated variable, just update variable as usual.
925 //
926 Status = AuthServiceInternalUpdateVariable (VariableName, VendorGuid, Data, DataSize, Attributes);
927 return Status;
928 }
929
930 /**
931 Filter out the duplicated EFI_SIGNATURE_DATA from the new data by comparing to the original data.
932
933 @param[in] Data Pointer to original EFI_SIGNATURE_LIST.
934 @param[in] DataSize Size of Data buffer.
935 @param[in, out] NewData Pointer to new EFI_SIGNATURE_LIST.
936 @param[in, out] NewDataSize Size of NewData buffer.
937
938 **/
939 EFI_STATUS
940 FilterSignatureList (
941 IN VOID *Data,
942 IN UINTN DataSize,
943 IN OUT VOID *NewData,
944 IN OUT UINTN *NewDataSize
945 )
946 {
947 EFI_SIGNATURE_LIST *CertList;
948 EFI_SIGNATURE_DATA *Cert;
949 UINTN CertCount;
950 EFI_SIGNATURE_LIST *NewCertList;
951 EFI_SIGNATURE_DATA *NewCert;
952 UINTN NewCertCount;
953 UINTN Index;
954 UINTN Index2;
955 UINTN Size;
956 UINT8 *Tail;
957 UINTN CopiedCount;
958 UINTN SignatureListSize;
959 BOOLEAN IsNewCert;
960 UINT8 *TempData;
961 UINTN TempDataSize;
962 EFI_STATUS Status;
963
964 if (*NewDataSize == 0) {
965 return EFI_SUCCESS;
966 }
967
968 TempDataSize = *NewDataSize;
969 Status = mAuthVarLibContextIn->GetScratchBuffer (&TempDataSize, (VOID **)&TempData);
970 if (EFI_ERROR (Status)) {
971 return EFI_OUT_OF_RESOURCES;
972 }
973
974 Tail = TempData;
975
976 NewCertList = (EFI_SIGNATURE_LIST *)NewData;
977 while ((*NewDataSize > 0) && (*NewDataSize >= NewCertList->SignatureListSize)) {
978 NewCert = (EFI_SIGNATURE_DATA *)((UINT8 *)NewCertList + sizeof (EFI_SIGNATURE_LIST) + NewCertList->SignatureHeaderSize);
979 NewCertCount = (NewCertList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - NewCertList->SignatureHeaderSize) / NewCertList->SignatureSize;
980
981 CopiedCount = 0;
982 for (Index = 0; Index < NewCertCount; Index++) {
983 IsNewCert = TRUE;
984
985 Size = DataSize;
986 CertList = (EFI_SIGNATURE_LIST *)Data;
987 while ((Size > 0) && (Size >= CertList->SignatureListSize)) {
988 if (CompareGuid (&CertList->SignatureType, &NewCertList->SignatureType) &&
989 (CertList->SignatureSize == NewCertList->SignatureSize))
990 {
991 Cert = (EFI_SIGNATURE_DATA *)((UINT8 *)CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize);
992 CertCount = (CertList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - CertList->SignatureHeaderSize) / CertList->SignatureSize;
993 for (Index2 = 0; Index2 < CertCount; Index2++) {
994 //
995 // Iterate each Signature Data in this Signature List.
996 //
997 if (CompareMem (NewCert, Cert, CertList->SignatureSize) == 0) {
998 IsNewCert = FALSE;
999 break;
1000 }
1001
1002 Cert = (EFI_SIGNATURE_DATA *)((UINT8 *)Cert + CertList->SignatureSize);
1003 }
1004 }
1005
1006 if (!IsNewCert) {
1007 break;
1008 }
1009
1010 Size -= CertList->SignatureListSize;
1011 CertList = (EFI_SIGNATURE_LIST *)((UINT8 *)CertList + CertList->SignatureListSize);
1012 }
1013
1014 if (IsNewCert) {
1015 //
1016 // New EFI_SIGNATURE_DATA, keep it.
1017 //
1018 if (CopiedCount == 0) {
1019 //
1020 // Copy EFI_SIGNATURE_LIST header for only once.
1021 //
1022 CopyMem (Tail, NewCertList, sizeof (EFI_SIGNATURE_LIST) + NewCertList->SignatureHeaderSize);
1023 Tail = Tail + sizeof (EFI_SIGNATURE_LIST) + NewCertList->SignatureHeaderSize;
1024 }
1025
1026 CopyMem (Tail, NewCert, NewCertList->SignatureSize);
1027 Tail += NewCertList->SignatureSize;
1028 CopiedCount++;
1029 }
1030
1031 NewCert = (EFI_SIGNATURE_DATA *)((UINT8 *)NewCert + NewCertList->SignatureSize);
1032 }
1033
1034 //
1035 // Update SignatureListSize in the kept EFI_SIGNATURE_LIST.
1036 //
1037 if (CopiedCount != 0) {
1038 SignatureListSize = sizeof (EFI_SIGNATURE_LIST) + NewCertList->SignatureHeaderSize + (CopiedCount * NewCertList->SignatureSize);
1039 CertList = (EFI_SIGNATURE_LIST *)(Tail - SignatureListSize);
1040 CertList->SignatureListSize = (UINT32)SignatureListSize;
1041 }
1042
1043 *NewDataSize -= NewCertList->SignatureListSize;
1044 NewCertList = (EFI_SIGNATURE_LIST *)((UINT8 *)NewCertList + NewCertList->SignatureListSize);
1045 }
1046
1047 TempDataSize = (Tail - (UINT8 *)TempData);
1048
1049 CopyMem (NewData, TempData, TempDataSize);
1050 *NewDataSize = TempDataSize;
1051
1052 return EFI_SUCCESS;
1053 }
1054
1055 /**
1056 Compare two EFI_TIME data.
1057
1058
1059 @param FirstTime A pointer to the first EFI_TIME data.
1060 @param SecondTime A pointer to the second EFI_TIME data.
1061
1062 @retval TRUE The FirstTime is not later than the SecondTime.
1063 @retval FALSE The FirstTime is later than the SecondTime.
1064
1065 **/
1066 BOOLEAN
1067 AuthServiceInternalCompareTimeStamp (
1068 IN EFI_TIME *FirstTime,
1069 IN EFI_TIME *SecondTime
1070 )
1071 {
1072 if (FirstTime->Year != SecondTime->Year) {
1073 return (BOOLEAN)(FirstTime->Year < SecondTime->Year);
1074 } else if (FirstTime->Month != SecondTime->Month) {
1075 return (BOOLEAN)(FirstTime->Month < SecondTime->Month);
1076 } else if (FirstTime->Day != SecondTime->Day) {
1077 return (BOOLEAN)(FirstTime->Day < SecondTime->Day);
1078 } else if (FirstTime->Hour != SecondTime->Hour) {
1079 return (BOOLEAN)(FirstTime->Hour < SecondTime->Hour);
1080 } else if (FirstTime->Minute != SecondTime->Minute) {
1081 return (BOOLEAN)(FirstTime->Minute < SecondTime->Minute);
1082 }
1083
1084 return (BOOLEAN)(FirstTime->Second <= SecondTime->Second);
1085 }
1086
1087 /**
1088 Calculate SHA256 digest of SignerCert CommonName + ToplevelCert tbsCertificate
1089 SignerCert and ToplevelCert are inside the signer certificate chain.
1090
1091 @param[in] SignerCert A pointer to SignerCert data.
1092 @param[in] SignerCertSize Length of SignerCert data.
1093 @param[in] TopLevelCert A pointer to TopLevelCert data.
1094 @param[in] TopLevelCertSize Length of TopLevelCert data.
1095 @param[out] Sha256Digest Sha256 digest calculated.
1096
1097 @return EFI_ABORTED Digest process failed.
1098 @return EFI_SUCCESS SHA256 Digest is successfully calculated.
1099
1100 **/
1101 EFI_STATUS
1102 CalculatePrivAuthVarSignChainSHA256Digest (
1103 IN UINT8 *SignerCert,
1104 IN UINTN SignerCertSize,
1105 IN UINT8 *TopLevelCert,
1106 IN UINTN TopLevelCertSize,
1107 OUT UINT8 *Sha256Digest
1108 )
1109 {
1110 UINT8 *TbsCert;
1111 UINTN TbsCertSize;
1112 CHAR8 CertCommonName[128];
1113 UINTN CertCommonNameSize;
1114 BOOLEAN CryptoStatus;
1115 EFI_STATUS Status;
1116
1117 CertCommonNameSize = sizeof (CertCommonName);
1118
1119 //
1120 // Get SignerCert CommonName
1121 //
1122 Status = X509GetCommonName (SignerCert, SignerCertSize, CertCommonName, &CertCommonNameSize);
1123 if (EFI_ERROR (Status)) {
1124 DEBUG ((DEBUG_INFO, "%a Get SignerCert CommonName failed with status %x\n", __FUNCTION__, Status));
1125 return EFI_ABORTED;
1126 }
1127
1128 //
1129 // Get TopLevelCert tbsCertificate
1130 //
1131 if (!X509GetTBSCert (TopLevelCert, TopLevelCertSize, &TbsCert, &TbsCertSize)) {
1132 DEBUG ((DEBUG_INFO, "%a Get Top-level Cert tbsCertificate failed!\n", __FUNCTION__));
1133 return EFI_ABORTED;
1134 }
1135
1136 //
1137 // Digest SignerCert CN + TopLevelCert tbsCertificate
1138 //
1139 ZeroMem (Sha256Digest, SHA256_DIGEST_SIZE);
1140 CryptoStatus = Sha256Init (mHashCtx);
1141 if (!CryptoStatus) {
1142 return EFI_ABORTED;
1143 }
1144
1145 //
1146 // '\0' is forced in CertCommonName. No overflow issue
1147 //
1148 CryptoStatus = Sha256Update (
1149 mHashCtx,
1150 CertCommonName,
1151 AsciiStrLen (CertCommonName)
1152 );
1153 if (!CryptoStatus) {
1154 return EFI_ABORTED;
1155 }
1156
1157 CryptoStatus = Sha256Update (mHashCtx, TbsCert, TbsCertSize);
1158 if (!CryptoStatus) {
1159 return EFI_ABORTED;
1160 }
1161
1162 CryptoStatus = Sha256Final (mHashCtx, Sha256Digest);
1163 if (!CryptoStatus) {
1164 return EFI_ABORTED;
1165 }
1166
1167 return EFI_SUCCESS;
1168 }
1169
1170 /**
1171 Find matching signer's certificates for common authenticated variable
1172 by corresponding VariableName and VendorGuid from "certdb" or "certdbv".
1173
1174 The data format of "certdb" or "certdbv":
1175 //
1176 // UINT32 CertDbListSize;
1177 // /// AUTH_CERT_DB_DATA Certs1[];
1178 // /// AUTH_CERT_DB_DATA Certs2[];
1179 // /// ...
1180 // /// AUTH_CERT_DB_DATA Certsn[];
1181 //
1182
1183 @param[in] VariableName Name of authenticated Variable.
1184 @param[in] VendorGuid Vendor GUID of authenticated Variable.
1185 @param[in] Data Pointer to variable "certdb" or "certdbv".
1186 @param[in] DataSize Size of variable "certdb" or "certdbv".
1187 @param[out] CertOffset Offset of matching CertData, from starting of Data.
1188 @param[out] CertDataSize Length of CertData in bytes.
1189 @param[out] CertNodeOffset Offset of matching AUTH_CERT_DB_DATA , from
1190 starting of Data.
1191 @param[out] CertNodeSize Length of AUTH_CERT_DB_DATA in bytes.
1192
1193 @retval EFI_INVALID_PARAMETER Any input parameter is invalid.
1194 @retval EFI_NOT_FOUND Fail to find matching certs.
1195 @retval EFI_SUCCESS Find matching certs and output parameters.
1196
1197 **/
1198 EFI_STATUS
1199 FindCertsFromDb (
1200 IN CHAR16 *VariableName,
1201 IN EFI_GUID *VendorGuid,
1202 IN UINT8 *Data,
1203 IN UINTN DataSize,
1204 OUT UINT32 *CertOffset OPTIONAL,
1205 OUT UINT32 *CertDataSize OPTIONAL,
1206 OUT UINT32 *CertNodeOffset OPTIONAL,
1207 OUT UINT32 *CertNodeSize OPTIONAL
1208 )
1209 {
1210 UINT32 Offset;
1211 AUTH_CERT_DB_DATA *Ptr;
1212 UINT32 CertSize;
1213 UINT32 NameSize;
1214 UINT32 NodeSize;
1215 UINT32 CertDbListSize;
1216
1217 if ((VariableName == NULL) || (VendorGuid == NULL) || (Data == NULL)) {
1218 return EFI_INVALID_PARAMETER;
1219 }
1220
1221 //
1222 // Check whether DataSize matches recorded CertDbListSize.
1223 //
1224 if (DataSize < sizeof (UINT32)) {
1225 return EFI_INVALID_PARAMETER;
1226 }
1227
1228 CertDbListSize = ReadUnaligned32 ((UINT32 *)Data);
1229
1230 if (CertDbListSize != (UINT32)DataSize) {
1231 return EFI_INVALID_PARAMETER;
1232 }
1233
1234 Offset = sizeof (UINT32);
1235
1236 //
1237 // Get corresponding certificates by VendorGuid and VariableName.
1238 //
1239 while (Offset < (UINT32)DataSize) {
1240 Ptr = (AUTH_CERT_DB_DATA *)(Data + Offset);
1241 //
1242 // Check whether VendorGuid matches.
1243 //
1244 if (CompareGuid (&Ptr->VendorGuid, VendorGuid)) {
1245 NodeSize = ReadUnaligned32 (&Ptr->CertNodeSize);
1246 NameSize = ReadUnaligned32 (&Ptr->NameSize);
1247 CertSize = ReadUnaligned32 (&Ptr->CertDataSize);
1248
1249 if (NodeSize != sizeof (EFI_GUID) + sizeof (UINT32) * 3 + CertSize +
1250 sizeof (CHAR16) * NameSize)
1251 {
1252 return EFI_INVALID_PARAMETER;
1253 }
1254
1255 Offset = Offset + sizeof (EFI_GUID) + sizeof (UINT32) * 3;
1256 //
1257 // Check whether VariableName matches.
1258 //
1259 if ((NameSize == StrLen (VariableName)) &&
1260 (CompareMem (Data + Offset, VariableName, NameSize * sizeof (CHAR16)) == 0))
1261 {
1262 Offset = Offset + NameSize * sizeof (CHAR16);
1263
1264 if (CertOffset != NULL) {
1265 *CertOffset = Offset;
1266 }
1267
1268 if (CertDataSize != NULL) {
1269 *CertDataSize = CertSize;
1270 }
1271
1272 if (CertNodeOffset != NULL) {
1273 *CertNodeOffset = (UINT32)((UINT8 *)Ptr - Data);
1274 }
1275
1276 if (CertNodeSize != NULL) {
1277 *CertNodeSize = NodeSize;
1278 }
1279
1280 return EFI_SUCCESS;
1281 } else {
1282 Offset = Offset + NameSize * sizeof (CHAR16) + CertSize;
1283 }
1284 } else {
1285 NodeSize = ReadUnaligned32 (&Ptr->CertNodeSize);
1286 Offset = Offset + NodeSize;
1287 }
1288 }
1289
1290 return EFI_NOT_FOUND;
1291 }
1292
1293 /**
1294 Retrieve signer's certificates for common authenticated variable
1295 by corresponding VariableName and VendorGuid from "certdb"
1296 or "certdbv" according to authenticated variable attributes.
1297
1298 @param[in] VariableName Name of authenticated Variable.
1299 @param[in] VendorGuid Vendor GUID of authenticated Variable.
1300 @param[in] Attributes Attributes of authenticated variable.
1301 @param[out] CertData Pointer to signer's certificates.
1302 @param[out] CertDataSize Length of CertData in bytes.
1303
1304 @retval EFI_INVALID_PARAMETER Any input parameter is invalid.
1305 @retval EFI_NOT_FOUND Fail to find "certdb"/"certdbv" or matching certs.
1306 @retval EFI_SUCCESS Get signer's certificates successfully.
1307
1308 **/
1309 EFI_STATUS
1310 GetCertsFromDb (
1311 IN CHAR16 *VariableName,
1312 IN EFI_GUID *VendorGuid,
1313 IN UINT32 Attributes,
1314 OUT UINT8 **CertData,
1315 OUT UINT32 *CertDataSize
1316 )
1317 {
1318 EFI_STATUS Status;
1319 UINT8 *Data;
1320 UINTN DataSize;
1321 UINT32 CertOffset;
1322 CHAR16 *DbName;
1323
1324 if ((VariableName == NULL) || (VendorGuid == NULL) || (CertData == NULL) || (CertDataSize == NULL)) {
1325 return EFI_INVALID_PARAMETER;
1326 }
1327
1328 if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
1329 //
1330 // Get variable "certdb".
1331 //
1332 DbName = EFI_CERT_DB_NAME;
1333 } else {
1334 //
1335 // Get variable "certdbv".
1336 //
1337 DbName = EFI_CERT_DB_VOLATILE_NAME;
1338 }
1339
1340 //
1341 // Get variable "certdb" or "certdbv".
1342 //
1343 Status = AuthServiceInternalFindVariable (
1344 DbName,
1345 &gEfiCertDbGuid,
1346 (VOID **)&Data,
1347 &DataSize
1348 );
1349 if (EFI_ERROR (Status)) {
1350 return Status;
1351 }
1352
1353 if ((DataSize == 0) || (Data == NULL)) {
1354 ASSERT (FALSE);
1355 return EFI_NOT_FOUND;
1356 }
1357
1358 Status = FindCertsFromDb (
1359 VariableName,
1360 VendorGuid,
1361 Data,
1362 DataSize,
1363 &CertOffset,
1364 CertDataSize,
1365 NULL,
1366 NULL
1367 );
1368
1369 if (EFI_ERROR (Status)) {
1370 return Status;
1371 }
1372
1373 *CertData = Data + CertOffset;
1374 return EFI_SUCCESS;
1375 }
1376
1377 /**
1378 Delete matching signer's certificates when deleting common authenticated
1379 variable by corresponding VariableName and VendorGuid from "certdb" or
1380 "certdbv" according to authenticated variable attributes.
1381
1382 @param[in] VariableName Name of authenticated Variable.
1383 @param[in] VendorGuid Vendor GUID of authenticated Variable.
1384 @param[in] Attributes Attributes of authenticated variable.
1385
1386 @retval EFI_INVALID_PARAMETER Any input parameter is invalid.
1387 @retval EFI_NOT_FOUND Fail to find "certdb"/"certdbv" or matching certs.
1388 @retval EFI_OUT_OF_RESOURCES The operation is failed due to lack of resources.
1389 @retval EFI_SUCCESS The operation is completed successfully.
1390
1391 **/
1392 EFI_STATUS
1393 DeleteCertsFromDb (
1394 IN CHAR16 *VariableName,
1395 IN EFI_GUID *VendorGuid,
1396 IN UINT32 Attributes
1397 )
1398 {
1399 EFI_STATUS Status;
1400 UINT8 *Data;
1401 UINTN DataSize;
1402 UINT32 VarAttr;
1403 UINT32 CertNodeOffset;
1404 UINT32 CertNodeSize;
1405 UINT8 *NewCertDb;
1406 UINT32 NewCertDbSize;
1407 CHAR16 *DbName;
1408
1409 if ((VariableName == NULL) || (VendorGuid == NULL)) {
1410 return EFI_INVALID_PARAMETER;
1411 }
1412
1413 if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
1414 //
1415 // Get variable "certdb".
1416 //
1417 DbName = EFI_CERT_DB_NAME;
1418 VarAttr = EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS;
1419 } else {
1420 //
1421 // Get variable "certdbv".
1422 //
1423 DbName = EFI_CERT_DB_VOLATILE_NAME;
1424 VarAttr = EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS;
1425 }
1426
1427 Status = AuthServiceInternalFindVariable (
1428 DbName,
1429 &gEfiCertDbGuid,
1430 (VOID **)&Data,
1431 &DataSize
1432 );
1433
1434 if (EFI_ERROR (Status)) {
1435 return Status;
1436 }
1437
1438 if ((DataSize == 0) || (Data == NULL)) {
1439 ASSERT (FALSE);
1440 return EFI_NOT_FOUND;
1441 }
1442
1443 if (DataSize == sizeof (UINT32)) {
1444 //
1445 // There is no certs in "certdb" or "certdbv".
1446 //
1447 return EFI_SUCCESS;
1448 }
1449
1450 //
1451 // Get corresponding cert node from "certdb" or "certdbv".
1452 //
1453 Status = FindCertsFromDb (
1454 VariableName,
1455 VendorGuid,
1456 Data,
1457 DataSize,
1458 NULL,
1459 NULL,
1460 &CertNodeOffset,
1461 &CertNodeSize
1462 );
1463
1464 if (EFI_ERROR (Status)) {
1465 return Status;
1466 }
1467
1468 if (DataSize < (CertNodeOffset + CertNodeSize)) {
1469 return EFI_NOT_FOUND;
1470 }
1471
1472 //
1473 // Construct new data content of variable "certdb" or "certdbv".
1474 //
1475 NewCertDbSize = (UINT32)DataSize - CertNodeSize;
1476 NewCertDb = (UINT8 *)mCertDbStore;
1477
1478 //
1479 // Copy the DB entries before deleting node.
1480 //
1481 CopyMem (NewCertDb, Data, CertNodeOffset);
1482 //
1483 // Update CertDbListSize.
1484 //
1485 CopyMem (NewCertDb, &NewCertDbSize, sizeof (UINT32));
1486 //
1487 // Copy the DB entries after deleting node.
1488 //
1489 if (DataSize > (CertNodeOffset + CertNodeSize)) {
1490 CopyMem (
1491 NewCertDb + CertNodeOffset,
1492 Data + CertNodeOffset + CertNodeSize,
1493 DataSize - CertNodeOffset - CertNodeSize
1494 );
1495 }
1496
1497 //
1498 // Set "certdb" or "certdbv".
1499 //
1500 Status = AuthServiceInternalUpdateVariable (
1501 DbName,
1502 &gEfiCertDbGuid,
1503 NewCertDb,
1504 NewCertDbSize,
1505 VarAttr
1506 );
1507
1508 return Status;
1509 }
1510
1511 /**
1512 Insert signer's certificates for common authenticated variable with VariableName
1513 and VendorGuid in AUTH_CERT_DB_DATA to "certdb" or "certdbv" according to
1514 time based authenticated variable attributes. CertData is the SHA256 digest of
1515 SignerCert CommonName + TopLevelCert tbsCertificate.
1516
1517 @param[in] VariableName Name of authenticated Variable.
1518 @param[in] VendorGuid Vendor GUID of authenticated Variable.
1519 @param[in] Attributes Attributes of authenticated variable.
1520 @param[in] SignerCert Signer certificate data.
1521 @param[in] SignerCertSize Length of signer certificate.
1522 @param[in] TopLevelCert Top-level certificate data.
1523 @param[in] TopLevelCertSize Length of top-level certificate.
1524
1525 @retval EFI_INVALID_PARAMETER Any input parameter is invalid.
1526 @retval EFI_ACCESS_DENIED An AUTH_CERT_DB_DATA entry with same VariableName
1527 and VendorGuid already exists.
1528 @retval EFI_OUT_OF_RESOURCES The operation is failed due to lack of resources.
1529 @retval EFI_SUCCESS Insert an AUTH_CERT_DB_DATA entry to "certdb" or "certdbv"
1530
1531 **/
1532 EFI_STATUS
1533 InsertCertsToDb (
1534 IN CHAR16 *VariableName,
1535 IN EFI_GUID *VendorGuid,
1536 IN UINT32 Attributes,
1537 IN UINT8 *SignerCert,
1538 IN UINTN SignerCertSize,
1539 IN UINT8 *TopLevelCert,
1540 IN UINTN TopLevelCertSize
1541 )
1542 {
1543 EFI_STATUS Status;
1544 UINT8 *Data;
1545 UINTN DataSize;
1546 UINT32 VarAttr;
1547 UINT8 *NewCertDb;
1548 UINT32 NewCertDbSize;
1549 UINT32 CertNodeSize;
1550 UINT32 NameSize;
1551 UINT32 CertDataSize;
1552 AUTH_CERT_DB_DATA *Ptr;
1553 CHAR16 *DbName;
1554 UINT8 Sha256Digest[SHA256_DIGEST_SIZE];
1555
1556 if ((VariableName == NULL) || (VendorGuid == NULL) || (SignerCert == NULL) || (TopLevelCert == NULL)) {
1557 return EFI_INVALID_PARAMETER;
1558 }
1559
1560 if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
1561 //
1562 // Get variable "certdb".
1563 //
1564 DbName = EFI_CERT_DB_NAME;
1565 VarAttr = EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS;
1566 } else {
1567 //
1568 // Get variable "certdbv".
1569 //
1570 DbName = EFI_CERT_DB_VOLATILE_NAME;
1571 VarAttr = EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS;
1572 }
1573
1574 //
1575 // Get variable "certdb" or "certdbv".
1576 //
1577 Status = AuthServiceInternalFindVariable (
1578 DbName,
1579 &gEfiCertDbGuid,
1580 (VOID **)&Data,
1581 &DataSize
1582 );
1583 if (EFI_ERROR (Status)) {
1584 return Status;
1585 }
1586
1587 if ((DataSize == 0) || (Data == NULL)) {
1588 ASSERT (FALSE);
1589 return EFI_NOT_FOUND;
1590 }
1591
1592 //
1593 // Find whether matching cert node already exists in "certdb" or "certdbv".
1594 // If yes return error.
1595 //
1596 Status = FindCertsFromDb (
1597 VariableName,
1598 VendorGuid,
1599 Data,
1600 DataSize,
1601 NULL,
1602 NULL,
1603 NULL,
1604 NULL
1605 );
1606
1607 if (!EFI_ERROR (Status)) {
1608 ASSERT (FALSE);
1609 return EFI_ACCESS_DENIED;
1610 }
1611
1612 //
1613 // Construct new data content of variable "certdb" or "certdbv".
1614 //
1615 NameSize = (UINT32)StrLen (VariableName);
1616 CertDataSize = sizeof (Sha256Digest);
1617 CertNodeSize = sizeof (AUTH_CERT_DB_DATA) + (UINT32)CertDataSize + NameSize * sizeof (CHAR16);
1618 NewCertDbSize = (UINT32)DataSize + CertNodeSize;
1619 if (NewCertDbSize > mMaxCertDbSize) {
1620 return EFI_OUT_OF_RESOURCES;
1621 }
1622
1623 Status = CalculatePrivAuthVarSignChainSHA256Digest (
1624 SignerCert,
1625 SignerCertSize,
1626 TopLevelCert,
1627 TopLevelCertSize,
1628 Sha256Digest
1629 );
1630 if (EFI_ERROR (Status)) {
1631 return Status;
1632 }
1633
1634 NewCertDb = (UINT8 *)mCertDbStore;
1635
1636 //
1637 // Copy the DB entries before inserting node.
1638 //
1639 CopyMem (NewCertDb, Data, DataSize);
1640 //
1641 // Update CertDbListSize.
1642 //
1643 CopyMem (NewCertDb, &NewCertDbSize, sizeof (UINT32));
1644 //
1645 // Construct new cert node.
1646 //
1647 Ptr = (AUTH_CERT_DB_DATA *)(NewCertDb + DataSize);
1648 CopyGuid (&Ptr->VendorGuid, VendorGuid);
1649 CopyMem (&Ptr->CertNodeSize, &CertNodeSize, sizeof (UINT32));
1650 CopyMem (&Ptr->NameSize, &NameSize, sizeof (UINT32));
1651 CopyMem (&Ptr->CertDataSize, &CertDataSize, sizeof (UINT32));
1652
1653 CopyMem (
1654 (UINT8 *)Ptr + sizeof (AUTH_CERT_DB_DATA),
1655 VariableName,
1656 NameSize * sizeof (CHAR16)
1657 );
1658
1659 CopyMem (
1660 (UINT8 *)Ptr + sizeof (AUTH_CERT_DB_DATA) + NameSize * sizeof (CHAR16),
1661 Sha256Digest,
1662 CertDataSize
1663 );
1664
1665 //
1666 // Set "certdb" or "certdbv".
1667 //
1668 Status = AuthServiceInternalUpdateVariable (
1669 DbName,
1670 &gEfiCertDbGuid,
1671 NewCertDb,
1672 NewCertDbSize,
1673 VarAttr
1674 );
1675
1676 return Status;
1677 }
1678
1679 /**
1680 Clean up signer's certificates for common authenticated variable
1681 by corresponding VariableName and VendorGuid from "certdb".
1682 System may break down during Timebased Variable update & certdb update,
1683 make them inconsistent, this function is called in AuthVariable Init
1684 to ensure consistency.
1685
1686 @retval EFI_NOT_FOUND Fail to find variable "certdb".
1687 @retval EFI_OUT_OF_RESOURCES The operation is failed due to lack of resources.
1688 @retval EFI_SUCCESS The operation is completed successfully.
1689
1690 **/
1691 EFI_STATUS
1692 CleanCertsFromDb (
1693 VOID
1694 )
1695 {
1696 UINT32 Offset;
1697 AUTH_CERT_DB_DATA *Ptr;
1698 UINT32 NameSize;
1699 UINT32 NodeSize;
1700 CHAR16 *VariableName;
1701 EFI_STATUS Status;
1702 BOOLEAN CertCleaned;
1703 UINT8 *Data;
1704 UINTN DataSize;
1705 EFI_GUID AuthVarGuid;
1706 AUTH_VARIABLE_INFO AuthVariableInfo;
1707
1708 Status = EFI_SUCCESS;
1709
1710 //
1711 // Get corresponding certificates by VendorGuid and VariableName.
1712 //
1713 do {
1714 CertCleaned = FALSE;
1715
1716 //
1717 // Get latest variable "certdb"
1718 //
1719 Status = AuthServiceInternalFindVariable (
1720 EFI_CERT_DB_NAME,
1721 &gEfiCertDbGuid,
1722 (VOID **)&Data,
1723 &DataSize
1724 );
1725 if (EFI_ERROR (Status)) {
1726 return Status;
1727 }
1728
1729 if ((DataSize == 0) || (Data == NULL)) {
1730 ASSERT (FALSE);
1731 return EFI_NOT_FOUND;
1732 }
1733
1734 Offset = sizeof (UINT32);
1735
1736 while (Offset < (UINT32)DataSize) {
1737 Ptr = (AUTH_CERT_DB_DATA *)(Data + Offset);
1738 NodeSize = ReadUnaligned32 (&Ptr->CertNodeSize);
1739 NameSize = ReadUnaligned32 (&Ptr->NameSize);
1740
1741 //
1742 // Get VarName tailed with '\0'
1743 //
1744 VariableName = AllocateZeroPool ((NameSize + 1) * sizeof (CHAR16));
1745 if (VariableName == NULL) {
1746 return EFI_OUT_OF_RESOURCES;
1747 }
1748
1749 CopyMem (VariableName, (UINT8 *)Ptr + sizeof (AUTH_CERT_DB_DATA), NameSize * sizeof (CHAR16));
1750 //
1751 // Keep VarGuid aligned
1752 //
1753 CopyMem (&AuthVarGuid, &Ptr->VendorGuid, sizeof (EFI_GUID));
1754
1755 //
1756 // Find corresponding time auth variable
1757 //
1758 ZeroMem (&AuthVariableInfo, sizeof (AuthVariableInfo));
1759 Status = mAuthVarLibContextIn->FindVariable (
1760 VariableName,
1761 &AuthVarGuid,
1762 &AuthVariableInfo
1763 );
1764
1765 if (EFI_ERROR (Status) || ((AuthVariableInfo.Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) == 0)) {
1766 //
1767 // While cleaning certdb, always delete the variable in certdb regardless of it attributes.
1768 //
1769 Status = DeleteCertsFromDb (
1770 VariableName,
1771 &AuthVarGuid,
1772 AuthVariableInfo.Attributes | EFI_VARIABLE_NON_VOLATILE
1773 );
1774 CertCleaned = TRUE;
1775 DEBUG ((DEBUG_INFO, "Recovery!! Cert for Auth Variable %s Guid %g is removed for consistency\n", VariableName, &AuthVarGuid));
1776 FreePool (VariableName);
1777 break;
1778 }
1779
1780 FreePool (VariableName);
1781 Offset = Offset + NodeSize;
1782 }
1783 } while (CertCleaned);
1784
1785 return Status;
1786 }
1787
1788 /**
1789 Process variable with EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS set
1790
1791 Caution: This function may receive untrusted input.
1792 This function may be invoked in SMM mode, and datasize and data are external input.
1793 This function will do basic validation, before parse the data.
1794 This function will parse the authentication carefully to avoid security issues, like
1795 buffer overflow, integer overflow.
1796
1797 @param[in] VariableName Name of Variable to be found.
1798 @param[in] VendorGuid Variable vendor GUID.
1799 @param[in] Data Data pointer.
1800 @param[in] DataSize Size of Data found. If size is less than the
1801 data, this value contains the required size.
1802 @param[in] Attributes Attribute value of the variable.
1803 @param[in] AuthVarType Verify against PK, KEK database, private database or certificate in data payload.
1804 @param[in] OrgTimeStamp Pointer to original time stamp,
1805 original variable is not found if NULL.
1806 @param[out] VarPayloadPtr Pointer to variable payload address.
1807 @param[out] VarPayloadSize Pointer to variable payload size.
1808
1809 @retval EFI_INVALID_PARAMETER Invalid parameter.
1810 @retval EFI_SECURITY_VIOLATION The variable does NOT pass the validation
1811 check carried out by the firmware.
1812 @retval EFI_OUT_OF_RESOURCES Failed to process variable due to lack
1813 of resources.
1814 @retval EFI_SUCCESS Variable pass validation successfully.
1815
1816 **/
1817 EFI_STATUS
1818 VerifyTimeBasedPayload (
1819 IN CHAR16 *VariableName,
1820 IN EFI_GUID *VendorGuid,
1821 IN VOID *Data,
1822 IN UINTN DataSize,
1823 IN UINT32 Attributes,
1824 IN AUTHVAR_TYPE AuthVarType,
1825 IN EFI_TIME *OrgTimeStamp,
1826 OUT UINT8 **VarPayloadPtr,
1827 OUT UINTN *VarPayloadSize
1828 )
1829 {
1830 EFI_VARIABLE_AUTHENTICATION_2 *CertData;
1831 UINT8 *SigData;
1832 UINT32 SigDataSize;
1833 UINT8 *PayloadPtr;
1834 UINTN PayloadSize;
1835 UINT32 Attr;
1836 BOOLEAN VerifyStatus;
1837 EFI_STATUS Status;
1838 EFI_SIGNATURE_LIST *CertList;
1839 EFI_SIGNATURE_DATA *Cert;
1840 UINTN Index;
1841 UINTN CertCount;
1842 UINT32 KekDataSize;
1843 UINT8 *NewData;
1844 UINTN NewDataSize;
1845 UINT8 *Buffer;
1846 UINTN Length;
1847 UINT8 *TopLevelCert;
1848 UINTN TopLevelCertSize;
1849 UINT8 *TrustedCert;
1850 UINTN TrustedCertSize;
1851 UINT8 *SignerCerts;
1852 UINTN CertStackSize;
1853 UINT8 *CertsInCertDb;
1854 UINT32 CertsSizeinDb;
1855 UINT8 Sha256Digest[SHA256_DIGEST_SIZE];
1856 EFI_CERT_DATA *CertDataPtr;
1857
1858 //
1859 // 1. TopLevelCert is the top-level issuer certificate in signature Signer Cert Chain
1860 // 2. TrustedCert is the certificate which firmware trusts. It could be saved in protected
1861 // storage or PK payload on PK init
1862 //
1863 VerifyStatus = FALSE;
1864 CertData = NULL;
1865 NewData = NULL;
1866 Attr = Attributes;
1867 SignerCerts = NULL;
1868 TopLevelCert = NULL;
1869 CertsInCertDb = NULL;
1870 CertDataPtr = NULL;
1871
1872 //
1873 // When the attribute EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS is
1874 // set, then the Data buffer shall begin with an instance of a complete (and serialized)
1875 // EFI_VARIABLE_AUTHENTICATION_2 descriptor. The descriptor shall be followed by the new
1876 // variable value and DataSize shall reflect the combined size of the descriptor and the new
1877 // variable value. The authentication descriptor is not part of the variable data and is not
1878 // returned by subsequent calls to GetVariable().
1879 //
1880 CertData = (EFI_VARIABLE_AUTHENTICATION_2 *)Data;
1881
1882 //
1883 // Verify that Pad1, Nanosecond, TimeZone, Daylight and Pad2 components of the
1884 // TimeStamp value are set to zero.
1885 //
1886 if ((CertData->TimeStamp.Pad1 != 0) ||
1887 (CertData->TimeStamp.Nanosecond != 0) ||
1888 (CertData->TimeStamp.TimeZone != 0) ||
1889 (CertData->TimeStamp.Daylight != 0) ||
1890 (CertData->TimeStamp.Pad2 != 0))
1891 {
1892 return EFI_SECURITY_VIOLATION;
1893 }
1894
1895 if ((OrgTimeStamp != NULL) && ((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0)) {
1896 if (AuthServiceInternalCompareTimeStamp (&CertData->TimeStamp, OrgTimeStamp)) {
1897 //
1898 // TimeStamp check fail, suspicious replay attack, return EFI_SECURITY_VIOLATION.
1899 //
1900 return EFI_SECURITY_VIOLATION;
1901 }
1902 }
1903
1904 //
1905 // wCertificateType should be WIN_CERT_TYPE_EFI_GUID.
1906 // Cert type should be EFI_CERT_TYPE_PKCS7_GUID.
1907 //
1908 if ((CertData->AuthInfo.Hdr.wCertificateType != WIN_CERT_TYPE_EFI_GUID) ||
1909 !CompareGuid (&CertData->AuthInfo.CertType, &gEfiCertPkcs7Guid))
1910 {
1911 //
1912 // Invalid AuthInfo type, return EFI_SECURITY_VIOLATION.
1913 //
1914 return EFI_SECURITY_VIOLATION;
1915 }
1916
1917 //
1918 // Find out Pkcs7 SignedData which follows the EFI_VARIABLE_AUTHENTICATION_2 descriptor.
1919 // AuthInfo.Hdr.dwLength is the length of the entire certificate, including the length of the header.
1920 //
1921 SigData = CertData->AuthInfo.CertData;
1922 SigDataSize = CertData->AuthInfo.Hdr.dwLength - (UINT32)(OFFSET_OF (WIN_CERTIFICATE_UEFI_GUID, CertData));
1923
1924 //
1925 // SignedData.digestAlgorithms shall contain the digest algorithm used when preparing the
1926 // signature. Only a digest algorithm of SHA-256 is accepted.
1927 //
1928 // According to PKCS#7 Definition:
1929 // SignedData ::= SEQUENCE {
1930 // version Version,
1931 // digestAlgorithms DigestAlgorithmIdentifiers,
1932 // contentInfo ContentInfo,
1933 // .... }
1934 // The DigestAlgorithmIdentifiers can be used to determine the hash algorithm
1935 // in VARIABLE_AUTHENTICATION_2 descriptor.
1936 // This field has the fixed offset (+13) and be calculated based on two bytes of length encoding.
1937 //
1938 if ((Attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) != 0) {
1939 if (SigDataSize >= (13 + sizeof (mSha256OidValue))) {
1940 if (((*(SigData + 1) & TWO_BYTE_ENCODE) != TWO_BYTE_ENCODE) ||
1941 (CompareMem (SigData + 13, &mSha256OidValue, sizeof (mSha256OidValue)) != 0))
1942 {
1943 return EFI_SECURITY_VIOLATION;
1944 }
1945 }
1946 }
1947
1948 //
1949 // Find out the new data payload which follows Pkcs7 SignedData directly.
1950 //
1951 PayloadPtr = SigData + SigDataSize;
1952 PayloadSize = DataSize - OFFSET_OF_AUTHINFO2_CERT_DATA - (UINTN)SigDataSize;
1953
1954 // If the VariablePolicy engine is disabled, allow deletion of any authenticated variables.
1955 if ((PayloadSize == 0) && ((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0) && !IsVariablePolicyEnabled ()) {
1956 VerifyStatus = TRUE;
1957 goto Exit;
1958 }
1959
1960 //
1961 // Construct a serialization buffer of the values of the VariableName, VendorGuid and Attributes
1962 // parameters of the SetVariable() call and the TimeStamp component of the
1963 // EFI_VARIABLE_AUTHENTICATION_2 descriptor followed by the variable's new value
1964 // i.e. (VariableName, VendorGuid, Attributes, TimeStamp, Data)
1965 //
1966 NewDataSize = PayloadSize + sizeof (EFI_TIME) + sizeof (UINT32) +
1967 sizeof (EFI_GUID) + StrSize (VariableName) - sizeof (CHAR16);
1968
1969 //
1970 // Here is to reuse scratch data area(at the end of volatile variable store)
1971 // to reduce SMRAM consumption for SMM variable driver.
1972 // The scratch buffer is enough to hold the serialized data and safe to use,
1973 // because it is only used at here to do verification temporarily first
1974 // and then used in UpdateVariable() for a time based auth variable set.
1975 //
1976 Status = mAuthVarLibContextIn->GetScratchBuffer (&NewDataSize, (VOID **)&NewData);
1977 if (EFI_ERROR (Status)) {
1978 return EFI_OUT_OF_RESOURCES;
1979 }
1980
1981 Buffer = NewData;
1982 Length = StrLen (VariableName) * sizeof (CHAR16);
1983 CopyMem (Buffer, VariableName, Length);
1984 Buffer += Length;
1985
1986 Length = sizeof (EFI_GUID);
1987 CopyMem (Buffer, VendorGuid, Length);
1988 Buffer += Length;
1989
1990 Length = sizeof (UINT32);
1991 CopyMem (Buffer, &Attr, Length);
1992 Buffer += Length;
1993
1994 Length = sizeof (EFI_TIME);
1995 CopyMem (Buffer, &CertData->TimeStamp, Length);
1996 Buffer += Length;
1997
1998 CopyMem (Buffer, PayloadPtr, PayloadSize);
1999
2000 if (AuthVarType == AuthVarTypePk) {
2001 //
2002 // Verify that the signature has been made with the current Platform Key (no chaining for PK).
2003 // First, get signer's certificates from SignedData.
2004 //
2005 VerifyStatus = Pkcs7GetSigners (
2006 SigData,
2007 SigDataSize,
2008 &SignerCerts,
2009 &CertStackSize,
2010 &TopLevelCert,
2011 &TopLevelCertSize
2012 );
2013 if (!VerifyStatus) {
2014 goto Exit;
2015 }
2016
2017 //
2018 // Second, get the current platform key from variable. Check whether it's identical with signer's certificates
2019 // in SignedData. If not, return error immediately.
2020 //
2021 Status = AuthServiceInternalFindVariable (
2022 EFI_PLATFORM_KEY_NAME,
2023 &gEfiGlobalVariableGuid,
2024 &Data,
2025 &DataSize
2026 );
2027 if (EFI_ERROR (Status)) {
2028 VerifyStatus = FALSE;
2029 goto Exit;
2030 }
2031
2032 CertList = (EFI_SIGNATURE_LIST *)Data;
2033 Cert = (EFI_SIGNATURE_DATA *)((UINT8 *)CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize);
2034 if ((TopLevelCertSize != (CertList->SignatureSize - (sizeof (EFI_SIGNATURE_DATA) - 1))) ||
2035 (CompareMem (Cert->SignatureData, TopLevelCert, TopLevelCertSize) != 0))
2036 {
2037 VerifyStatus = FALSE;
2038 goto Exit;
2039 }
2040
2041 //
2042 // Verify Pkcs7 SignedData via Pkcs7Verify library.
2043 //
2044 VerifyStatus = Pkcs7Verify (
2045 SigData,
2046 SigDataSize,
2047 TopLevelCert,
2048 TopLevelCertSize,
2049 NewData,
2050 NewDataSize
2051 );
2052 } else if (AuthVarType == AuthVarTypeKek) {
2053 //
2054 // Get KEK database from variable.
2055 //
2056 Status = AuthServiceInternalFindVariable (
2057 EFI_KEY_EXCHANGE_KEY_NAME,
2058 &gEfiGlobalVariableGuid,
2059 &Data,
2060 &DataSize
2061 );
2062 if (EFI_ERROR (Status)) {
2063 return Status;
2064 }
2065
2066 //
2067 // Ready to verify Pkcs7 SignedData. Go through KEK Signature Database to find out X.509 CertList.
2068 //
2069 KekDataSize = (UINT32)DataSize;
2070 CertList = (EFI_SIGNATURE_LIST *)Data;
2071 while ((KekDataSize > 0) && (KekDataSize >= CertList->SignatureListSize)) {
2072 if (CompareGuid (&CertList->SignatureType, &gEfiCertX509Guid)) {
2073 Cert = (EFI_SIGNATURE_DATA *)((UINT8 *)CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize);
2074 CertCount = (CertList->SignatureListSize - sizeof (EFI_SIGNATURE_LIST) - CertList->SignatureHeaderSize) / CertList->SignatureSize;
2075 for (Index = 0; Index < CertCount; Index++) {
2076 //
2077 // Iterate each Signature Data Node within this CertList for a verify
2078 //
2079 TrustedCert = Cert->SignatureData;
2080 TrustedCertSize = CertList->SignatureSize - (sizeof (EFI_SIGNATURE_DATA) - 1);
2081
2082 //
2083 // Verify Pkcs7 SignedData via Pkcs7Verify library.
2084 //
2085 VerifyStatus = Pkcs7Verify (
2086 SigData,
2087 SigDataSize,
2088 TrustedCert,
2089 TrustedCertSize,
2090 NewData,
2091 NewDataSize
2092 );
2093 if (VerifyStatus) {
2094 goto Exit;
2095 }
2096
2097 Cert = (EFI_SIGNATURE_DATA *)((UINT8 *)Cert + CertList->SignatureSize);
2098 }
2099 }
2100
2101 KekDataSize -= CertList->SignatureListSize;
2102 CertList = (EFI_SIGNATURE_LIST *)((UINT8 *)CertList + CertList->SignatureListSize);
2103 }
2104 } else if (AuthVarType == AuthVarTypePriv) {
2105 //
2106 // Process common authenticated variable except PK/KEK/DB/DBX/DBT.
2107 // Get signer's certificates from SignedData.
2108 //
2109 VerifyStatus = Pkcs7GetSigners (
2110 SigData,
2111 SigDataSize,
2112 &SignerCerts,
2113 &CertStackSize,
2114 &TopLevelCert,
2115 &TopLevelCertSize
2116 );
2117 if (!VerifyStatus) {
2118 goto Exit;
2119 }
2120
2121 //
2122 // Get previously stored signer's certificates from certdb or certdbv for existing
2123 // variable. Check whether they are identical with signer's certificates
2124 // in SignedData. If not, return error immediately.
2125 //
2126 if (OrgTimeStamp != NULL) {
2127 VerifyStatus = FALSE;
2128
2129 Status = GetCertsFromDb (VariableName, VendorGuid, Attributes, &CertsInCertDb, &CertsSizeinDb);
2130 if (EFI_ERROR (Status)) {
2131 goto Exit;
2132 }
2133
2134 if (CertsSizeinDb == SHA256_DIGEST_SIZE) {
2135 //
2136 // Check hash of signer cert CommonName + Top-level issuer tbsCertificate against data in CertDb
2137 //
2138 CertDataPtr = (EFI_CERT_DATA *)(SignerCerts + 1);
2139 Status = CalculatePrivAuthVarSignChainSHA256Digest (
2140 CertDataPtr->CertDataBuffer,
2141 ReadUnaligned32 ((UINT32 *)&(CertDataPtr->CertDataLength)),
2142 TopLevelCert,
2143 TopLevelCertSize,
2144 Sha256Digest
2145 );
2146 if (EFI_ERROR (Status) || (CompareMem (Sha256Digest, CertsInCertDb, CertsSizeinDb) != 0)) {
2147 goto Exit;
2148 }
2149 } else {
2150 //
2151 // Keep backward compatible with previous solution which saves whole signer certs stack in CertDb
2152 //
2153 if ((CertStackSize != CertsSizeinDb) ||
2154 (CompareMem (SignerCerts, CertsInCertDb, CertsSizeinDb) != 0))
2155 {
2156 goto Exit;
2157 }
2158 }
2159 }
2160
2161 VerifyStatus = Pkcs7Verify (
2162 SigData,
2163 SigDataSize,
2164 TopLevelCert,
2165 TopLevelCertSize,
2166 NewData,
2167 NewDataSize
2168 );
2169 if (!VerifyStatus) {
2170 goto Exit;
2171 }
2172
2173 if ((OrgTimeStamp == NULL) && (PayloadSize != 0)) {
2174 //
2175 // When adding a new common authenticated variable, always save Hash of cn of signer cert + tbsCertificate of Top-level issuer
2176 //
2177 CertDataPtr = (EFI_CERT_DATA *)(SignerCerts + 1);
2178 Status = InsertCertsToDb (
2179 VariableName,
2180 VendorGuid,
2181 Attributes,
2182 CertDataPtr->CertDataBuffer,
2183 ReadUnaligned32 ((UINT32 *)&(CertDataPtr->CertDataLength)),
2184 TopLevelCert,
2185 TopLevelCertSize
2186 );
2187 if (EFI_ERROR (Status)) {
2188 VerifyStatus = FALSE;
2189 goto Exit;
2190 }
2191 }
2192 } else if (AuthVarType == AuthVarTypePayload) {
2193 CertList = (EFI_SIGNATURE_LIST *)PayloadPtr;
2194 Cert = (EFI_SIGNATURE_DATA *)((UINT8 *)CertList + sizeof (EFI_SIGNATURE_LIST) + CertList->SignatureHeaderSize);
2195 TrustedCert = Cert->SignatureData;
2196 TrustedCertSize = CertList->SignatureSize - (sizeof (EFI_SIGNATURE_DATA) - 1);
2197 //
2198 // Verify Pkcs7 SignedData via Pkcs7Verify library.
2199 //
2200 VerifyStatus = Pkcs7Verify (
2201 SigData,
2202 SigDataSize,
2203 TrustedCert,
2204 TrustedCertSize,
2205 NewData,
2206 NewDataSize
2207 );
2208 } else {
2209 return EFI_SECURITY_VIOLATION;
2210 }
2211
2212 Exit:
2213
2214 if ((AuthVarType == AuthVarTypePk) || (AuthVarType == AuthVarTypePriv)) {
2215 if (TopLevelCert != NULL) {
2216 Pkcs7FreeSigners (TopLevelCert);
2217 }
2218
2219 if (SignerCerts != NULL) {
2220 Pkcs7FreeSigners (SignerCerts);
2221 }
2222 }
2223
2224 if (!VerifyStatus) {
2225 return EFI_SECURITY_VIOLATION;
2226 }
2227
2228 Status = CheckSignatureListFormat (VariableName, VendorGuid, PayloadPtr, PayloadSize);
2229 if (EFI_ERROR (Status)) {
2230 return Status;
2231 }
2232
2233 *VarPayloadPtr = PayloadPtr;
2234 *VarPayloadSize = PayloadSize;
2235
2236 return EFI_SUCCESS;
2237 }
2238
2239 /**
2240 Process variable with EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS set
2241
2242 Caution: This function may receive untrusted input.
2243 This function may be invoked in SMM mode, and datasize and data are external input.
2244 This function will do basic validation, before parse the data.
2245 This function will parse the authentication carefully to avoid security issues, like
2246 buffer overflow, integer overflow.
2247
2248 @param[in] VariableName Name of Variable to be found.
2249 @param[in] VendorGuid Variable vendor GUID.
2250 @param[in] Data Data pointer.
2251 @param[in] DataSize Size of Data found. If size is less than the
2252 data, this value contains the required size.
2253 @param[in] Attributes Attribute value of the variable.
2254 @param[in] AuthVarType Verify against PK, KEK database, private database or certificate in data payload.
2255 @param[out] VarDel Delete the variable or not.
2256
2257 @retval EFI_INVALID_PARAMETER Invalid parameter.
2258 @retval EFI_SECURITY_VIOLATION The variable does NOT pass the validation
2259 check carried out by the firmware.
2260 @retval EFI_OUT_OF_RESOURCES Failed to process variable due to lack
2261 of resources.
2262 @retval EFI_SUCCESS Variable pass validation successfully.
2263
2264 **/
2265 EFI_STATUS
2266 VerifyTimeBasedPayloadAndUpdate (
2267 IN CHAR16 *VariableName,
2268 IN EFI_GUID *VendorGuid,
2269 IN VOID *Data,
2270 IN UINTN DataSize,
2271 IN UINT32 Attributes,
2272 IN AUTHVAR_TYPE AuthVarType,
2273 OUT BOOLEAN *VarDel
2274 )
2275 {
2276 EFI_STATUS Status;
2277 EFI_STATUS FindStatus;
2278 UINT8 *PayloadPtr;
2279 UINTN PayloadSize;
2280 EFI_VARIABLE_AUTHENTICATION_2 *CertData;
2281 AUTH_VARIABLE_INFO OrgVariableInfo;
2282 BOOLEAN IsDel;
2283
2284 ZeroMem (&OrgVariableInfo, sizeof (OrgVariableInfo));
2285 FindStatus = mAuthVarLibContextIn->FindVariable (
2286 VariableName,
2287 VendorGuid,
2288 &OrgVariableInfo
2289 );
2290
2291 Status = VerifyTimeBasedPayload (
2292 VariableName,
2293 VendorGuid,
2294 Data,
2295 DataSize,
2296 Attributes,
2297 AuthVarType,
2298 (!EFI_ERROR (FindStatus)) ? OrgVariableInfo.TimeStamp : NULL,
2299 &PayloadPtr,
2300 &PayloadSize
2301 );
2302 if (EFI_ERROR (Status)) {
2303 return Status;
2304 }
2305
2306 if ( !EFI_ERROR (FindStatus)
2307 && (PayloadSize == 0)
2308 && ((Attributes & EFI_VARIABLE_APPEND_WRITE) == 0))
2309 {
2310 IsDel = TRUE;
2311 } else {
2312 IsDel = FALSE;
2313 }
2314
2315 CertData = (EFI_VARIABLE_AUTHENTICATION_2 *)Data;
2316
2317 //
2318 // Final step: Update/Append Variable if it pass Pkcs7Verify
2319 //
2320 Status = AuthServiceInternalUpdateVariableWithTimeStamp (
2321 VariableName,
2322 VendorGuid,
2323 PayloadPtr,
2324 PayloadSize,
2325 Attributes,
2326 &CertData->TimeStamp
2327 );
2328
2329 //
2330 // Delete signer's certificates when delete the common authenticated variable.
2331 //
2332 if (IsDel && (AuthVarType == AuthVarTypePriv) && !EFI_ERROR (Status)) {
2333 Status = DeleteCertsFromDb (VariableName, VendorGuid, Attributes);
2334 }
2335
2336 if (VarDel != NULL) {
2337 if (IsDel && !EFI_ERROR (Status)) {
2338 *VarDel = TRUE;
2339 } else {
2340 *VarDel = FALSE;
2341 }
2342 }
2343
2344 return Status;
2345 }
EFI Development Kit II mirror for PVE