1 /** @file
2 
3 Copyright (c) 2010 - 2015, Intel Corporation. All rights reserved.<BR>
4 
5 This program and the accompanying materials
6 are licensed and made available under the terms and conditions
7 of the BSD License which accompanies this distribution.  The
8 full text of the license may be found at
9 http://opensource.org/licenses/bsd-license.php
10 
11 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
12 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
13 
14 **/
15 
16 #include <PiSmm.h>
17 #include <Library/SmmServicesTableLib.h>
18 #include <Library/BaseLib.h>
19 #include <Library/BaseMemoryLib.h>
20 #include <Library/LockBoxLib.h>
21 #include <Library/DebugLib.h>
22 #include <Guid/SmmLockBox.h>
23 
24 #include "SmmLockBoxLibPrivate.h"
25 
26 /**
27   We need handle this library carefully. Only one library instance will construct the environment.
28   Below 2 global variable can only be used in constructor. They should NOT be used in any other library functions.
29 **/
30 SMM_LOCK_BOX_CONTEXT mSmmLockBoxContext;
31 LIST_ENTRY           mLockBoxQueue = INITIALIZE_LIST_HEAD_VARIABLE (mLockBoxQueue);
32 
33 /**
34   This function return SmmLockBox context from SMST.
35 
36   @return SmmLockBox context from SMST.
37 **/
38 SMM_LOCK_BOX_CONTEXT *
InternalGetSmmLockBoxContext(VOID)39 InternalGetSmmLockBoxContext (
40   VOID
41   )
42 {
43   UINTN   Index;
44 
45   //
46   // Check if gEfiSmmLockBoxCommunicationGuid is installed by someone
47   //
48   for (Index = 0; Index < gSmst->NumberOfTableEntries; Index++) {
49     if (CompareGuid (&gSmst->SmmConfigurationTable[Index].VendorGuid, &gEfiSmmLockBoxCommunicationGuid)) {
50       //
51       // Found. That means some other library instance is already run.
52       // No need to install again, just return.
53       //
54       return (SMM_LOCK_BOX_CONTEXT *)gSmst->SmmConfigurationTable[Index].VendorTable;
55     }
56   }
57 
58   //
59   // Not found.
60   //
61   return NULL;
62 }
63 
64 /**
65   Constructor for SmmLockBox library.
66   This is used to set SmmLockBox context, which will be used in PEI phase in S3 boot path later.
67 
68   @param[in] ImageHandle  Image handle of this driver.
69   @param[in] SystemTable  A Pointer to the EFI System Table.
70 
71   @retval EFI_SUCEESS
72   @return Others          Some error occurs.
73 **/
74 EFI_STATUS
75 EFIAPI
SmmLockBoxSmmConstructuor(IN EFI_HANDLE ImageHandle,IN EFI_SYSTEM_TABLE * SystemTable)76 SmmLockBoxSmmConstructuor (
77   IN EFI_HANDLE        ImageHandle,
78   IN EFI_SYSTEM_TABLE  *SystemTable
79   )
80 {
81   EFI_STATUS           Status;
82   SMM_LOCK_BOX_CONTEXT *SmmLockBoxContext;
83 
84   DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib SmmLockBoxSmmConstructuor - Enter\n"));
85 
86   //
87   // Check if gEfiSmmLockBoxCommunicationGuid is installed by someone
88   //
89   SmmLockBoxContext = InternalGetSmmLockBoxContext ();
90   if (SmmLockBoxContext != NULL) {
91     //
92     // Find it. That means some other library instance is already run.
93     // No need to install again, just return.
94     //
95     DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib SmmLockBoxContext - already installed\n"));
96     DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib SmmLockBoxSmmConstructuor - Exit\n"));
97     return EFI_SUCCESS;
98   }
99 
100   //
101   // If no one install this, it means this is first instance. Install it.
102   //
103   if (sizeof(UINTN) == sizeof(UINT64)) {
104     mSmmLockBoxContext.Signature = SMM_LOCK_BOX_SIGNATURE_64;
105   } else {
106     mSmmLockBoxContext.Signature = SMM_LOCK_BOX_SIGNATURE_32;
107   }
108   mSmmLockBoxContext.LockBoxDataAddress = (EFI_PHYSICAL_ADDRESS)(UINTN)&mLockBoxQueue;
109 
110   Status = gSmst->SmmInstallConfigurationTable (
111                     gSmst,
112                     &gEfiSmmLockBoxCommunicationGuid,
113                     &mSmmLockBoxContext,
114                     sizeof(mSmmLockBoxContext)
115                     );
116   ASSERT_EFI_ERROR (Status);
117 
118   DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib SmmLockBoxContext - %x\n", (UINTN)&mSmmLockBoxContext));
119   DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib LockBoxDataAddress - %x\n", (UINTN)&mLockBoxQueue));
120   DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib SmmLockBoxSmmConstructuor - Exit\n"));
121 
122   return Status;
123 }
124 
125 /**
126   This function return SmmLockBox queue address.
127 
128   @return SmmLockBox queue address.
129 **/
130 LIST_ENTRY *
InternalGetLockBoxQueue(VOID)131 InternalGetLockBoxQueue (
132   VOID
133   )
134 {
135   SMM_LOCK_BOX_CONTEXT        *SmmLockBoxContext;
136 
137   SmmLockBoxContext = InternalGetSmmLockBoxContext ();
138   ASSERT (SmmLockBoxContext != NULL);
139   if (SmmLockBoxContext == NULL) {
140     return NULL;
141   }
142   return (LIST_ENTRY *)(UINTN)SmmLockBoxContext->LockBoxDataAddress;
143 }
144 
145 /**
146   This function find LockBox by GUID.
147 
148   @param Guid The guid to indentify the LockBox
149 
150   @return LockBoxData
151 **/
152 SMM_LOCK_BOX_DATA *
InternalFindLockBoxByGuid(IN EFI_GUID * Guid)153 InternalFindLockBoxByGuid (
154   IN EFI_GUID   *Guid
155   )
156 {
157   LIST_ENTRY                    *Link;
158   SMM_LOCK_BOX_DATA             *LockBox;
159   LIST_ENTRY                    *LockBoxQueue;
160 
161   LockBoxQueue = InternalGetLockBoxQueue ();
162   ASSERT (LockBoxQueue != NULL);
163 
164   for (Link = LockBoxQueue->ForwardLink;
165        Link != LockBoxQueue;
166        Link = Link->ForwardLink) {
167     LockBox = BASE_CR (
168                 Link,
169                 SMM_LOCK_BOX_DATA,
170                 Link
171                 );
172     if (CompareGuid (&LockBox->Guid, Guid)) {
173       return LockBox;
174     }
175   }
176   return NULL;
177 }
178 
179 /**
180   This function will save confidential information to lockbox.
181 
182   @param Guid       the guid to identify the confidential information
183   @param Buffer     the address of the confidential information
184   @param Length     the length of the confidential information
185 
186   @retval RETURN_SUCCESS            the information is saved successfully.
187   @retval RETURN_INVALID_PARAMETER  the Guid is NULL, or Buffer is NULL, or Length is 0
188   @retval RETURN_ALREADY_STARTED    the requested GUID already exist.
189   @retval RETURN_OUT_OF_RESOURCES   no enough resource to save the information.
190   @retval RETURN_ACCESS_DENIED      it is too late to invoke this interface
191   @retval RETURN_NOT_STARTED        it is too early to invoke this interface
192   @retval RETURN_UNSUPPORTED        the service is not supported by implementaion.
193 **/
194 RETURN_STATUS
195 EFIAPI
SaveLockBox(IN GUID * Guid,IN VOID * Buffer,IN UINTN Length)196 SaveLockBox (
197   IN  GUID                        *Guid,
198   IN  VOID                        *Buffer,
199   IN  UINTN                       Length
200   )
201 {
202   SMM_LOCK_BOX_DATA           *LockBox;
203   EFI_PHYSICAL_ADDRESS        SmramBuffer;
204   EFI_STATUS                  Status;
205   LIST_ENTRY                  *LockBoxQueue;
206 
207   DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib SaveLockBox - Enter\n"));
208 
209   //
210   // Basic check
211   //
212   if ((Guid == NULL) || (Buffer == NULL) || (Length == 0)) {
213     DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib SaveLockBox - Exit (%r)\n", EFI_INVALID_PARAMETER));
214     return EFI_INVALID_PARAMETER;
215   }
216 
217   //
218   // Find LockBox
219   //
220   LockBox = InternalFindLockBoxByGuid (Guid);
221   if (LockBox != NULL) {
222     DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib SaveLockBox - Exit (%r)\n", EFI_ALREADY_STARTED));
223     return EFI_ALREADY_STARTED;
224   }
225 
226   //
227   // Allocate SMRAM buffer
228   //
229   Status = gSmst->SmmAllocatePages (
230                     AllocateAnyPages,
231                     EfiRuntimeServicesData,
232                     EFI_SIZE_TO_PAGES (Length),
233                     &SmramBuffer
234                     );
235   ASSERT_EFI_ERROR (Status);
236   if (EFI_ERROR (Status)) {
237     DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib SaveLockBox - Exit (%r)\n", EFI_OUT_OF_RESOURCES));
238     return EFI_OUT_OF_RESOURCES;
239   }
240 
241   //
242   // Allocate LockBox
243   //
244   Status = gSmst->SmmAllocatePool (
245                     EfiRuntimeServicesData,
246                     sizeof(*LockBox),
247                     (VOID **)&LockBox
248                     );
249   ASSERT_EFI_ERROR (Status);
250   if (EFI_ERROR (Status)) {
251     gSmst->SmmFreePages (SmramBuffer, EFI_SIZE_TO_PAGES (Length));
252     DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib SaveLockBox - Exit (%r)\n", EFI_OUT_OF_RESOURCES));
253     return EFI_OUT_OF_RESOURCES;
254   }
255 
256   //
257   // Save data
258   //
259   CopyMem ((VOID *)(UINTN)SmramBuffer, (VOID *)(UINTN)Buffer, Length);
260 
261   //
262   // Insert LockBox to queue
263   //
264   LockBox->Signature   = SMM_LOCK_BOX_DATA_SIGNATURE;
265   CopyMem (&LockBox->Guid, Guid, sizeof(EFI_GUID));
266   LockBox->Buffer      = (EFI_PHYSICAL_ADDRESS)(UINTN)Buffer;
267   LockBox->Length      = (UINT64)Length;
268   LockBox->Attributes  = 0;
269   LockBox->SmramBuffer = SmramBuffer;
270 
271   DEBUG ((
272     EFI_D_INFO,
273     "LockBoxGuid - %g, SmramBuffer - 0x%lx, Length - 0x%lx\n",
274     &LockBox->Guid,
275     LockBox->SmramBuffer,
276     LockBox->Length
277     ));
278 
279   LockBoxQueue = InternalGetLockBoxQueue ();
280   ASSERT (LockBoxQueue != NULL);
281   InsertTailList (LockBoxQueue, &LockBox->Link);
282 
283   //
284   // Done
285   //
286   DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib SaveLockBox - Exit (%r)\n", EFI_SUCCESS));
287   return EFI_SUCCESS;
288 }
289 
290 /**
291   This function will set lockbox attributes.
292 
293   @param Guid       the guid to identify the confidential information
294   @param Attributes the attributes of the lockbox
295 
296   @retval RETURN_SUCCESS            the information is saved successfully.
297   @retval RETURN_INVALID_PARAMETER  attributes is invalid.
298   @retval RETURN_NOT_FOUND          the requested GUID not found.
299   @retval RETURN_ACCESS_DENIED      it is too late to invoke this interface
300   @retval RETURN_NOT_STARTED        it is too early to invoke this interface
301   @retval RETURN_UNSUPPORTED        the service is not supported by implementaion.
302 **/
303 RETURN_STATUS
304 EFIAPI
SetLockBoxAttributes(IN GUID * Guid,IN UINT64 Attributes)305 SetLockBoxAttributes (
306   IN  GUID                        *Guid,
307   IN  UINT64                      Attributes
308   )
309 {
310   SMM_LOCK_BOX_DATA              *LockBox;
311 
312   DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib SetLockBoxAttributes - Enter\n"));
313 
314   //
315   // Basic check
316   //
317   if ((Guid == NULL) ||
318       ((Attributes & ~LOCK_BOX_ATTRIBUTE_RESTORE_IN_PLACE) != 0)) {
319     DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib SetLockBoxAttributes - Exit (%r)\n", EFI_INVALID_PARAMETER));
320     return EFI_INVALID_PARAMETER;
321   }
322 
323   //
324   // Find LockBox
325   //
326   LockBox = InternalFindLockBoxByGuid (Guid);
327   if (LockBox == NULL) {
328     DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib SetLockBoxAttributes - Exit (%r)\n", EFI_NOT_FOUND));
329     return EFI_NOT_FOUND;
330   }
331 
332   //
333   // Update data
334   //
335   LockBox->Attributes = Attributes;
336 
337   //
338   // Done
339   //
340   DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib SetLockBoxAttributes - Exit (%r)\n", EFI_SUCCESS));
341   return EFI_SUCCESS;
342 }
343 
344 /**
345   This function will update confidential information to lockbox.
346 
347   @param Guid   the guid to identify the original confidential information
348   @param Offset the offset of the original confidential information
349   @param Buffer the address of the updated confidential information
350   @param Length the length of the updated confidential information
351 
352   @retval RETURN_SUCCESS            the information is saved successfully.
353   @retval RETURN_INVALID_PARAMETER  the Guid is NULL, or Buffer is NULL, or Length is 0.
354   @retval RETURN_NOT_FOUND          the requested GUID not found.
355   @retval RETURN_BUFFER_TOO_SMALL   the original buffer to too small to hold new information.
356   @retval RETURN_ACCESS_DENIED      it is too late to invoke this interface
357   @retval RETURN_NOT_STARTED        it is too early to invoke this interface
358   @retval RETURN_UNSUPPORTED        the service is not supported by implementaion.
359 **/
360 RETURN_STATUS
361 EFIAPI
UpdateLockBox(IN GUID * Guid,IN UINTN Offset,IN VOID * Buffer,IN UINTN Length)362 UpdateLockBox (
363   IN  GUID                        *Guid,
364   IN  UINTN                       Offset,
365   IN  VOID                        *Buffer,
366   IN  UINTN                       Length
367   )
368 {
369   SMM_LOCK_BOX_DATA             *LockBox;
370 
371   DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib UpdateLockBox - Enter\n"));
372 
373   //
374   // Basic check
375   //
376   if ((Guid == NULL) || (Buffer == NULL) || (Length == 0)) {
377     DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib UpdateLockBox - Exit (%r)\n", EFI_INVALID_PARAMETER));
378     return EFI_INVALID_PARAMETER;
379   }
380 
381   //
382   // Find LockBox
383   //
384   LockBox = InternalFindLockBoxByGuid (Guid);
385   if (LockBox == NULL) {
386     DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib UpdateLockBox - Exit (%r)\n", EFI_NOT_FOUND));
387     return EFI_NOT_FOUND;
388   }
389 
390   //
391   // Update data
392   //
393   if (LockBox->Length < Offset + Length) {
394     DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib UpdateLockBox - Exit (%r)\n", EFI_BUFFER_TOO_SMALL));
395     return EFI_BUFFER_TOO_SMALL;
396   }
397   ASSERT ((UINTN)LockBox->SmramBuffer <= (MAX_ADDRESS - Offset));
398   CopyMem ((VOID *)((UINTN)LockBox->SmramBuffer + Offset), Buffer, Length);
399 
400   //
401   // Done
402   //
403   DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib UpdateLockBox - Exit (%r)\n", EFI_SUCCESS));
404   return EFI_SUCCESS;
405 }
406 
407 /**
408   This function will restore confidential information from lockbox.
409 
410   @param Guid   the guid to identify the confidential information
411   @param Buffer the address of the restored confidential information
412                 NULL means restored to original address, Length MUST be NULL at same time.
413   @param Length the length of the restored confidential information
414 
415   @retval RETURN_SUCCESS            the information is restored successfully.
416   @retval RETURN_INVALID_PARAMETER  the Guid is NULL, or one of Buffer and Length is NULL.
417   @retval RETURN_WRITE_PROTECTED    Buffer and Length are NULL, but the LockBox has no
418                                     LOCK_BOX_ATTRIBUTE_RESTORE_IN_PLACE attribute.
419   @retval RETURN_BUFFER_TOO_SMALL   the Length is too small to hold the confidential information.
420   @retval RETURN_NOT_FOUND          the requested GUID not found.
421   @retval RETURN_NOT_STARTED        it is too early to invoke this interface
422   @retval RETURN_ACCESS_DENIED      not allow to restore to the address
423   @retval RETURN_UNSUPPORTED        the service is not supported by implementaion.
424 **/
425 RETURN_STATUS
426 EFIAPI
RestoreLockBox(IN GUID * Guid,IN VOID * Buffer,OPTIONAL IN OUT UINTN * Length OPTIONAL)427 RestoreLockBox (
428   IN  GUID                        *Guid,
429   IN  VOID                        *Buffer, OPTIONAL
430   IN  OUT UINTN                   *Length  OPTIONAL
431   )
432 {
433   SMM_LOCK_BOX_DATA              *LockBox;
434   VOID                           *RestoreBuffer;
435 
436   DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib RestoreLockBox - Enter\n"));
437 
438   //
439   // Restore this, Buffer and Length MUST be both NULL or both non-NULL
440   //
441   if ((Guid == NULL) ||
442       ((Buffer == NULL) && (Length != NULL)) ||
443       ((Buffer != NULL) && (Length == NULL))) {
444     DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib RestoreLockBox - Exit (%r)\n", EFI_INVALID_PARAMETER));
445     return EFI_INVALID_PARAMETER;
446   }
447 
448   //
449   // Find LockBox
450   //
451   LockBox = InternalFindLockBoxByGuid (Guid);
452   if (LockBox == NULL) {
453     //
454     // Not found
455     //
456     DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib RestoreLockBox - Exit (%r)\n", EFI_NOT_FOUND));
457     return EFI_NOT_FOUND;
458   }
459 
460   //
461   // Set RestoreBuffer
462   //
463   if (Buffer != NULL) {
464     //
465     // restore to new buffer
466     //
467     RestoreBuffer = Buffer;
468   } else {
469     //
470     // restore to original buffer
471     //
472     if ((LockBox->Attributes & LOCK_BOX_ATTRIBUTE_RESTORE_IN_PLACE) == 0) {
473       DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib RestoreLockBox - Exit (%r)\n", EFI_WRITE_PROTECTED));
474       return EFI_WRITE_PROTECTED;
475     }
476     RestoreBuffer = (VOID *)(UINTN)LockBox->Buffer;
477   }
478 
479   //
480   // Set RestoreLength
481   //
482   if (Length != NULL) {
483     if (*Length < (UINTN)LockBox->Length) {
484       //
485       // Input buffer is too small to hold all data.
486       //
487       *Length = (UINTN)LockBox->Length;
488       DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib RestoreLockBox - Exit (%r)\n", EFI_BUFFER_TOO_SMALL));
489       return EFI_BUFFER_TOO_SMALL;
490     }
491     *Length = (UINTN)LockBox->Length;
492   }
493 
494   //
495   // Restore data
496   //
497   CopyMem (RestoreBuffer, (VOID *)(UINTN)LockBox->SmramBuffer, (UINTN)LockBox->Length);
498 
499   //
500   // Done
501   //
502   DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib RestoreLockBox - Exit (%r)\n", EFI_SUCCESS));
503   return EFI_SUCCESS;
504 }
505 
506 /**
507   This function will restore confidential information from all lockbox which have RestoreInPlace attribute.
508 
509   @retval RETURN_SUCCESS            the information is restored successfully.
510   @retval RETURN_NOT_STARTED        it is too early to invoke this interface
511   @retval RETURN_UNSUPPORTED        the service is not supported by implementaion.
512 **/
513 RETURN_STATUS
514 EFIAPI
RestoreAllLockBoxInPlace(VOID)515 RestoreAllLockBoxInPlace (
516   VOID
517   )
518 {
519   SMM_LOCK_BOX_DATA             *LockBox;
520   LIST_ENTRY                    *Link;
521   LIST_ENTRY                    *LockBoxQueue;
522 
523   DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib RestoreAllLockBoxInPlace - Enter\n"));
524 
525   LockBoxQueue = InternalGetLockBoxQueue ();
526   ASSERT (LockBoxQueue != NULL);
527 
528   //
529   // Restore all, Buffer and Length MUST be NULL
530   //
531   for (Link = LockBoxQueue->ForwardLink;
532        Link != LockBoxQueue;
533        Link = Link->ForwardLink) {
534     LockBox = BASE_CR (
535                 Link,
536                 SMM_LOCK_BOX_DATA,
537                 Link
538                 );
539     if ((LockBox->Attributes & LOCK_BOX_ATTRIBUTE_RESTORE_IN_PLACE) != 0) {
540       //
541       // Restore data
542       //
543       CopyMem ((VOID *)(UINTN)LockBox->Buffer, (VOID *)(UINTN)LockBox->SmramBuffer, (UINTN)LockBox->Length);
544     }
545   }
546   //
547   // Done
548   //
549   DEBUG ((EFI_D_INFO, "SmmLockBoxSmmLib RestoreAllLockBoxInPlace - Exit (%r)\n", EFI_SUCCESS));
550   return EFI_SUCCESS;
551 }
552 
553