SecurityPkg/VariableAuthenticated/RuntimeDxe/Variable.h

   1 /** @file
   2   The internal header file includes the common header files, defines
   3   internal structure and functions used by Variable modules.
   4
   5 Copyright (c) 2009 - 2014, Intel Corporation. All rights reserved.<BR>
   6 This program and the accompanying materials
   7 are licensed and made available under the terms and conditions of the BSD License
   8 which accompanies this distribution.  The 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 #ifndef _VARIABLE_H_
  17 #define _VARIABLE_H_
  18
  19 #include <PiDxe.h>
  20 #include <Protocol/VariableWrite.h>
  21 #include <Protocol/FaultTolerantWrite.h>
  22 #include <Protocol/FirmwareVolumeBlock.h>
  23 #include <Protocol/Variable.h>
  24 #include <Protocol/VariableLock.h>
  25 #include <Library/PcdLib.h>
  26 #include <Library/HobLib.h>
  27 #include <Library/UefiDriverEntryPoint.h>
  28 #include <Library/DxeServicesTableLib.h>
  29 #include <Library/UefiRuntimeLib.h>
  30 #include <Library/DebugLib.h>
  31 #include <Library/BaseMemoryLib.h>
  32 #include <Library/UefiBootServicesTableLib.h>
  33 #include <Library/UefiLib.h>
  34 #include <Library/BaseLib.h>
  35 #include <Library/SynchronizationLib.h>
  36 #include <Library/MemoryAllocationLib.h>
  37 #include <Library/BaseCryptLib.h>
  38 #include <Library/PlatformSecureLib.h>
  39 #include <Guid/GlobalVariable.h>
  40 #include <Guid/EventGroup.h>
  41 #include <Guid/AuthenticatedVariableFormat.h>
  42 #include <Guid/ImageAuthentication.h>
  43 #include <Guid/SystemNvDataGuid.h>
  44 #include <Guid/FaultTolerantWrite.h>
  45 #include <Guid/HardwareErrorVariable.h>
  46
  47 #define EFI_VARIABLE_ATTRIBUTES_MASK (EFI_VARIABLE_NON_VOLATILE | \
  48                                       EFI_VARIABLE_BOOTSERVICE_ACCESS | \
  49                                       EFI_VARIABLE_RUNTIME_ACCESS | \
  50                                       EFI_VARIABLE_HARDWARE_ERROR_RECORD | \
  51                                       EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS | \
  52                                       EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS | \
  53                                       EFI_VARIABLE_APPEND_WRITE)
  54
  55 #define VARIABLE_ATTRIBUTE_BS_RT        (EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS)
  56 #define VARIABLE_ATTRIBUTE_NV_BS_RT     (VARIABLE_ATTRIBUTE_BS_RT | EFI_VARIABLE_NON_VOLATILE)
  57 #define VARIABLE_ATTRIBUTE_NV_BS_RT_AT  (VARIABLE_ATTRIBUTE_NV_BS_RT | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS)
  58
  59 typedef struct {
  60   CHAR16      *Name;
  61   UINT32      Attributes;
  62 } GLOBAL_VARIABLE_ENTRY;
  63
  64 ///
  65 /// The size of a 3 character ISO639 language code.
  66 ///
  67 #define ISO_639_2_ENTRY_SIZE    3
  68
  69 typedef enum {
  70   VariableStoreTypeVolatile,
  71   VariableStoreTypeHob,
  72   VariableStoreTypeNv,
  73   VariableStoreTypeMax
  74 } VARIABLE_STORE_TYPE;
  75
  76 typedef struct {
  77   VARIABLE_HEADER *CurrPtr;
  78   //
  79   // If both ADDED and IN_DELETED_TRANSITION variable are present,
  80   // InDeletedTransitionPtr will point to the IN_DELETED_TRANSITION one.
  81   // Otherwise, CurrPtr will point to the ADDED or IN_DELETED_TRANSITION one,
  82   // and InDeletedTransitionPtr will be NULL at the same time.
  83   //
  84   VARIABLE_HEADER *InDeletedTransitionPtr;
  85   VARIABLE_HEADER *EndPtr;
  86   VARIABLE_HEADER *StartPtr;
  87   BOOLEAN         Volatile;
  88 } VARIABLE_POINTER_TRACK;
  89
  90 typedef struct {
  91   EFI_PHYSICAL_ADDRESS  HobVariableBase;
  92   EFI_PHYSICAL_ADDRESS  VolatileVariableBase;
  93   EFI_PHYSICAL_ADDRESS  NonVolatileVariableBase;
  94   EFI_LOCK              VariableServicesLock;
  95   UINT32                ReentrantState;
  96 } VARIABLE_GLOBAL;
  97
  98 typedef struct {
  99   VARIABLE_GLOBAL VariableGlobal;
 100   UINTN           VolatileLastVariableOffset;
 101   UINTN           NonVolatileLastVariableOffset;
 102   UINTN           CommonVariableTotalSize;
 103   UINTN           HwErrVariableTotalSize;
 104   CHAR8           *PlatformLangCodes;
 105   CHAR8           *LangCodes;
 106   CHAR8           *PlatformLang;
 107   CHAR8           Lang[ISO_639_2_ENTRY_SIZE + 1];
 108   EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL *FvbInstance;
 109 } VARIABLE_MODULE_GLOBAL;
 110
 111 typedef struct {
 112   EFI_GUID    *Guid;
 113   CHAR16      *Name;
 114   UINTN       VariableSize;
 115 } VARIABLE_ENTRY_CONSISTENCY;
 116
 117 typedef struct {
 118   EFI_GUID    Guid;
 119   CHAR16      *Name;
 120   LIST_ENTRY  Link;
 121 } VARIABLE_ENTRY;
 122
 123 /**
 124   Flush the HOB variable to flash.
 125
 126   @param[in] VariableName       Name of variable has been updated or deleted.
 127   @param[in] VendorGuid         Guid of variable has been updated or deleted.
 128
 129 **/
 130 VOID
 131 FlushHobVariableToFlash (
 132   IN CHAR16                     *VariableName,
 133   IN EFI_GUID                   *VendorGuid
 134   );
 135
 136 /**
 137   Writes a buffer to variable storage space, in the working block.
 138
 139   This function writes a buffer to variable storage space into a firmware
 140   volume block device. The destination is specified by the parameter
 141   VariableBase. Fault Tolerant Write protocol is used for writing.
 142
 143   @param  VariableBase   Base address of the variable to write.
 144   @param  VariableBuffer Point to the variable data buffer.
 145
 146   @retval EFI_SUCCESS    The function completed successfully.
 147   @retval EFI_NOT_FOUND  Fail to locate Fault Tolerant Write protocol.
 148   @retval EFI_ABORTED    The function could not complete successfully.
 149
 150 **/
 151 EFI_STATUS
 152 FtwVariableSpace (
 153   IN EFI_PHYSICAL_ADDRESS   VariableBase,
 154   IN VARIABLE_STORE_HEADER  *VariableBuffer
 155   );
 156
 157 /**
 158   Finds variable in storage blocks of volatile and non-volatile storage areas.
 159
 160   This code finds variable in storage blocks of volatile and non-volatile storage areas.
 161   If VariableName is an empty string, then we just return the first
 162   qualified variable without comparing VariableName and VendorGuid.
 163   If IgnoreRtCheck is TRUE, then we ignore the EFI_VARIABLE_RUNTIME_ACCESS attribute check
 164   at runtime when searching existing variable, only VariableName and VendorGuid are compared.
 165   Otherwise, variables without EFI_VARIABLE_RUNTIME_ACCESS are not visible at runtime.
 166
 167   @param[in]   VariableName           Name of the variable to be found.
 168   @param[in]   VendorGuid             Vendor GUID to be found.
 169   @param[out]  PtrTrack               VARIABLE_POINTER_TRACK structure for output,
 170                                       including the range searched and the target position.
 171   @param[in]   Global                 Pointer to VARIABLE_GLOBAL structure, including
 172                                       base of volatile variable storage area, base of
 173                                       NV variable storage area, and a lock.
 174   @param[in]   IgnoreRtCheck          Ignore EFI_VARIABLE_RUNTIME_ACCESS attribute
 175                                       check at runtime when searching variable.
 176
 177   @retval EFI_INVALID_PARAMETER       If VariableName is not an empty string, while
 178                                       VendorGuid is NULL.
 179   @retval EFI_SUCCESS                 Variable successfully found.
 180   @retval EFI_NOT_FOUND               Variable not found
 181
 182 **/
 183 EFI_STATUS
 184 FindVariable (
 185   IN  CHAR16                  *VariableName,
 186   IN  EFI_GUID                *VendorGuid,
 187   OUT VARIABLE_POINTER_TRACK  *PtrTrack,
 188   IN  VARIABLE_GLOBAL         *Global,
 189   IN  BOOLEAN                 IgnoreRtCheck
 190   );
 191
 192 /**
 193
 194   This code gets the pointer to the variable data.
 195
 196   @param Variable        Pointer to the Variable Header.
 197
 198   @return Pointer to Variable Data.
 199
 200 **/
 201 UINT8 *
 202 GetVariableDataPtr (
 203   IN  VARIABLE_HEADER   *Variable
 204   );
 205
 206 /**
 207
 208   This code gets the size of variable data.
 209
 210   @param Variable        Pointer to the Variable Header.
 211
 212   @return Size of variable in bytes.
 213
 214 **/
 215 UINTN
 216 DataSizeOfVariable (
 217   IN  VARIABLE_HEADER   *Variable
 218   );
 219
 220 /**
 221   This function is to check if the remaining variable space is enough to set
 222   all Variables from argument list successfully. The purpose of the check
 223   is to keep the consistency of the Variables to be in variable storage.
 224
 225   Note: Variables are assumed to be in same storage.
 226   The set sequence of Variables will be same with the sequence of VariableEntry from argument list,
 227   so follow the argument sequence to check the Variables.
 228
 229   @param[in] Attributes         Variable attributes for Variable entries.
 230   @param ...                    The variable argument list with type VARIABLE_ENTRY_CONSISTENCY *.
 231                                 A NULL terminates the list. The VariableSize of
 232                                 VARIABLE_ENTRY_CONSISTENCY is the variable data size as input.
 233                                 It will be changed to variable total size as output.
 234
 235   @retval TRUE                  Have enough variable space to set the Variables successfully.
 236   @retval FALSE                 No enough variable space to set the Variables successfully.
 237
 238 **/
 239 BOOLEAN
 240 EFIAPI
 241 CheckRemainingSpaceForConsistency (
 242   IN UINT32                     Attributes,
 243   ...
 244   );
 245
 246 /**
 247   Update the variable region with Variable information. If EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS is set,
 248   index of associated public key is needed.
 249
 250   @param[in] VariableName       Name of variable.
 251   @param[in] VendorGuid         Guid of variable.
 252   @param[in] Data               Variable data.
 253   @param[in] DataSize           Size of data. 0 means delete.
 254   @param[in] Attributes         Attributes of the variable.
 255   @param[in] KeyIndex           Index of associated public key.
 256   @param[in] MonotonicCount     Value of associated monotonic count.
 257   @param[in, out] Variable      The variable information that is used to keep track of variable usage.
 258
 259   @param[in] TimeStamp          Value of associated TimeStamp.
 260
 261   @retval EFI_SUCCESS           The update operation is success.
 262   @retval EFI_OUT_OF_RESOURCES  Variable region is full, cannot write other data into this region.
 263
 264 **/
 265 EFI_STATUS
 266 UpdateVariable (
 267   IN      CHAR16          *VariableName,
 268   IN      EFI_GUID        *VendorGuid,
 269   IN      VOID            *Data,
 270   IN      UINTN           DataSize,
 271   IN      UINT32          Attributes OPTIONAL,
 272   IN      UINT32          KeyIndex  OPTIONAL,
 273   IN      UINT64          MonotonicCount  OPTIONAL,
 274   IN OUT  VARIABLE_POINTER_TRACK *Variable,
 275   IN      EFI_TIME        *TimeStamp  OPTIONAL
 276   );
 277
 278
 279 /**
 280   Return TRUE if ExitBootServices () has been called.
 281
 282   @retval TRUE If ExitBootServices () has been called.
 283 **/
 284 BOOLEAN
 285 AtRuntime (
 286   VOID
 287   );
 288
 289 /**
 290   Initializes a basic mutual exclusion lock.
 291
 292   This function initializes a basic mutual exclusion lock to the released state
 293   and returns the lock.  Each lock provides mutual exclusion access at its task
 294   priority level.  Since there is no preemption or multiprocessor support in EFI,
 295   acquiring the lock only consists of raising to the locks TPL.
 296   If Lock is NULL, then ASSERT().
 297   If Priority is not a valid TPL value, then ASSERT().
 298
 299   @param  Lock       A pointer to the lock data structure to initialize.
 300   @param  Priority   EFI TPL is associated with the lock.
 301
 302   @return The lock.
 303
 304 **/
 305 EFI_LOCK *
 306 InitializeLock (
 307   IN OUT EFI_LOCK  *Lock,
 308   IN EFI_TPL        Priority
 309   );
 310
 311
 312 /**
 313   Acquires lock only at boot time. Simply returns at runtime.
 314
 315   This is a temperary function that will be removed when
 316   EfiAcquireLock() in UefiLib can handle the call in UEFI
 317   Runtimer driver in RT phase.
 318   It calls EfiAcquireLock() at boot time, and simply returns
 319   at runtime.
 320
 321   @param  Lock         A pointer to the lock to acquire.
 322
 323 **/
 324 VOID
 325 AcquireLockOnlyAtBootTime (
 326   IN EFI_LOCK  *Lock
 327   );
 328
 329
 330 /**
 331   Releases lock only at boot time. Simply returns at runtime.
 332
 333   This is a temperary function which will be removed when
 334   EfiReleaseLock() in UefiLib can handle the call in UEFI
 335   Runtimer driver in RT phase.
 336   It calls EfiReleaseLock() at boot time and simply returns
 337   at runtime.
 338
 339   @param  Lock         A pointer to the lock to release.
 340
 341 **/
 342 VOID
 343 ReleaseLockOnlyAtBootTime (
 344   IN EFI_LOCK  *Lock
 345   );
 346
 347 /**
 348   Retrive the FVB protocol interface by HANDLE.
 349
 350   @param[in]  FvBlockHandle     The handle of FVB protocol that provides services for
 351                                 reading, writing, and erasing the target block.
 352   @param[out] FvBlock           The interface of FVB protocol
 353
 354   @retval EFI_SUCCESS           The interface information for the specified protocol was returned.
 355   @retval EFI_UNSUPPORTED       The device does not support the FVB protocol.
 356   @retval EFI_INVALID_PARAMETER FvBlockHandle is not a valid EFI_HANDLE or FvBlock is NULL.
 357
 358 **/
 359 EFI_STATUS
 360 GetFvbByHandle (
 361   IN  EFI_HANDLE                          FvBlockHandle,
 362   OUT EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  **FvBlock
 363   );
 364
 365
 366 /**
 367   Retrive the Swap Address Range protocol interface.
 368
 369   @param[out] SarProtocol       The interface of SAR protocol
 370
 371   @retval EFI_SUCCESS           The SAR protocol instance was found and returned in SarProtocol.
 372   @retval EFI_NOT_FOUND         The SAR protocol instance was not found.
 373   @retval EFI_INVALID_PARAMETER SarProtocol is NULL.
 374
 375 **/
 376 EFI_STATUS
 377 GetSarProtocol (
 378   OUT VOID                                **SarProtocol
 379   );
 380
 381 /**
 382   Function returns an array of handles that support the FVB protocol
 383   in a buffer allocated from pool.
 384
 385   @param[out]  NumberHandles    The number of handles returned in Buffer.
 386   @param[out]  Buffer           A pointer to the buffer to return the requested
 387                                 array of  handles that support FVB protocol.
 388
 389   @retval EFI_SUCCESS           The array of handles was returned in Buffer, and the number of
 390                                 handles in Buffer was returned in NumberHandles.
 391   @retval EFI_NOT_FOUND         No FVB handle was found.
 392   @retval EFI_OUT_OF_RESOURCES  There is not enough pool memory to store the matching results.
 393   @retval EFI_INVALID_PARAMETER NumberHandles is NULL or Buffer is NULL.
 394
 395 **/
 396 EFI_STATUS
 397 GetFvbCountAndBuffer (
 398   OUT UINTN                               *NumberHandles,
 399   OUT EFI_HANDLE                          **Buffer
 400   );
 401
 402 /**
 403   Initializes variable store area for non-volatile and volatile variable.
 404
 405   @retval EFI_SUCCESS           Function successfully executed.
 406   @retval EFI_OUT_OF_RESOURCES  Fail to allocate enough memory resource.
 407
 408 **/
 409 EFI_STATUS
 410 VariableCommonInitialize (
 411   VOID
 412   );
 413
 414 /**
 415
 416   Variable store garbage collection and reclaim operation.
 417
 418   If ReclaimPubKeyStore is FALSE, reclaim variable space by deleting the obsoleted varaibles.
 419   If ReclaimPubKeyStore is TRUE, reclaim invalid key in public key database and update the PubKeyIndex
 420   for all the count-based authenticate variable in NV storage.
 421
 422   @param[in]      VariableBase            Base address of variable store.
 423   @param[out]     LastVariableOffset      Offset of last variable.
 424   @param[in]      IsVolatile              The variable store is volatile or not;
 425                                           if it is non-volatile, need FTW.
 426   @param[in, out] UpdatingPtrTrack        Pointer to updating variable pointer track structure.
 427   @param[in]      NewVariable             Pointer to new variable.
 428   @param[in]      NewVariableSize         New variable size.
 429   @param[in]      ReclaimPubKeyStore      Reclaim for public key database or not.
 430
 431   @return EFI_SUCCESS                  Reclaim operation has finished successfully.
 432   @return EFI_OUT_OF_RESOURCES         No enough memory resources or variable space.
 433   @return EFI_DEVICE_ERROR             The public key database doesn't exist.
 434   @return Others                       Unexpect error happened during reclaim operation.
 435
 436 **/
 437 EFI_STATUS
 438 Reclaim (
 439   IN     EFI_PHYSICAL_ADDRESS         VariableBase,
 440   OUT    UINTN                        *LastVariableOffset,
 441   IN     BOOLEAN                      IsVolatile,
 442   IN OUT VARIABLE_POINTER_TRACK       *UpdatingPtrTrack,
 443   IN     VARIABLE_HEADER              *NewVariable,
 444   IN     UINTN                        NewVariableSize,
 445   IN     BOOLEAN                      ReclaimPubKeyStore
 446   );
 447
 448 /**
 449   This function reclaims variable storage if free size is below the threshold.
 450
 451 **/
 452 VOID
 453 ReclaimForOS(
 454   VOID
 455   );
 456
 457
 458 /**
 459   Initializes variable write service after FVB was ready.
 460
 461   @retval EFI_SUCCESS          Function successfully executed.
 462   @retval Others               Fail to initialize the variable service.
 463
 464 **/
 465 EFI_STATUS
 466 VariableWriteServiceInitialize (
 467   VOID
 468   );
 469
 470 /**
 471   Retrive the SMM Fault Tolerent Write protocol interface.
 472
 473   @param[out] FtwProtocol       The interface of SMM Ftw protocol
 474
 475   @retval EFI_SUCCESS           The SMM SAR protocol instance was found and returned in SarProtocol.
 476   @retval EFI_NOT_FOUND         The SMM SAR protocol instance was not found.
 477   @retval EFI_INVALID_PARAMETER SarProtocol is NULL.
 478
 479 **/
 480 EFI_STATUS
 481 GetFtwProtocol (
 482   OUT VOID                                **FtwProtocol
 483   );
 484
 485 /**
 486   Get the proper fvb handle and/or fvb protocol by the given Flash address.
 487
 488   @param[in] Address        The Flash address.
 489   @param[out] FvbHandle     In output, if it is not NULL, it points to the proper FVB handle.
 490   @param[out] FvbProtocol   In output, if it is not NULL, it points to the proper FVB protocol.
 491
 492 **/
 493 EFI_STATUS
 494 GetFvbInfoByAddress (
 495   IN  EFI_PHYSICAL_ADDRESS                Address,
 496   OUT EFI_HANDLE                          *FvbHandle OPTIONAL,
 497   OUT EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  **FvbProtocol OPTIONAL
 498   );
 499
 500 /**
 501
 502   This code finds variable in storage blocks (Volatile or Non-Volatile).
 503
 504   Caution: This function may receive untrusted input.
 505   This function may be invoked in SMM mode, and datasize and data are external input.
 506   This function will do basic validation, before parse the data.
 507
 508   @param VariableName               Name of Variable to be found.
 509   @param VendorGuid                 Variable vendor GUID.
 510   @param Attributes                 Attribute value of the variable found.
 511   @param DataSize                   Size of Data found. If size is less than the
 512                                     data, this value contains the required size.
 513   @param Data                       Data pointer.
 514
 515   @return EFI_INVALID_PARAMETER     Invalid parameter.
 516   @return EFI_SUCCESS               Find the specified variable.
 517   @return EFI_NOT_FOUND             Not found.
 518   @return EFI_BUFFER_TO_SMALL       DataSize is too small for the result.
 519
 520 **/
 521 EFI_STATUS
 522 EFIAPI
 523 VariableServiceGetVariable (
 524   IN      CHAR16            *VariableName,
 525   IN      EFI_GUID          *VendorGuid,
 526   OUT     UINT32            *Attributes OPTIONAL,
 527   IN OUT  UINTN             *DataSize,
 528   OUT     VOID              *Data
 529   );
 530
 531 /**
 532
 533   This code Finds the Next available variable.
 534
 535   Caution: This function may receive untrusted input.
 536   This function may be invoked in SMM mode. This function will do basic validation, before parse the data.
 537
 538   @param VariableNameSize           Size of the variable name.
 539   @param VariableName               Pointer to variable name.
 540   @param VendorGuid                 Variable Vendor Guid.
 541
 542   @return EFI_INVALID_PARAMETER     Invalid parameter.
 543   @return EFI_SUCCESS               Find the specified variable.
 544   @return EFI_NOT_FOUND             Not found.
 545   @return EFI_BUFFER_TO_SMALL       DataSize is too small for the result.
 546
 547 **/
 548 EFI_STATUS
 549 EFIAPI
 550 VariableServiceGetNextVariableName (
 551   IN OUT  UINTN             *VariableNameSize,
 552   IN OUT  CHAR16            *VariableName,
 553   IN OUT  EFI_GUID          *VendorGuid
 554   );
 555
 556 /**
 557
 558   This code sets variable in storage blocks (Volatile or Non-Volatile).
 559
 560   Caution: This function may receive untrusted input.
 561   This function may be invoked in SMM mode, and datasize and data are external input.
 562   This function will do basic validation, before parse the data.
 563   This function will parse the authentication carefully to avoid security issues, like
 564   buffer overflow, integer overflow.
 565   This function will check attribute carefully to avoid authentication bypass.
 566
 567   @param VariableName                     Name of Variable to be found.
 568   @param VendorGuid                       Variable vendor GUID.
 569   @param Attributes                       Attribute value of the variable found
 570   @param DataSize                         Size of Data found. If size is less than the
 571                                           data, this value contains the required size.
 572   @param Data                             Data pointer.
 573
 574   @return EFI_INVALID_PARAMETER           Invalid parameter.
 575   @return EFI_SUCCESS                     Set successfully.
 576   @return EFI_OUT_OF_RESOURCES            Resource not enough to set variable.
 577   @return EFI_NOT_FOUND                   Not found.
 578   @return EFI_WRITE_PROTECTED             Variable is read-only.
 579
 580 **/
 581 EFI_STATUS
 582 EFIAPI
 583 VariableServiceSetVariable (
 584   IN CHAR16                  *VariableName,
 585   IN EFI_GUID                *VendorGuid,
 586   IN UINT32                  Attributes,
 587   IN UINTN                   DataSize,
 588   IN VOID                    *Data
 589   );
 590
 591 /**
 592
 593   This code returns information about the EFI variables.
 594
 595   Caution: This function may receive untrusted input.
 596   This function may be invoked in SMM mode. This function will do basic validation, before parse the data.
 597
 598   @param Attributes                     Attributes bitmask to specify the type of variables
 599                                         on which to return information.
 600   @param MaximumVariableStorageSize     Pointer to the maximum size of the storage space available
 601                                         for the EFI variables associated with the attributes specified.
 602   @param RemainingVariableStorageSize   Pointer to the remaining size of the storage space available
 603                                         for EFI variables associated with the attributes specified.
 604   @param MaximumVariableSize            Pointer to the maximum size of an individual EFI variables
 605                                         associated with the attributes specified.
 606
 607   @return EFI_SUCCESS                   Query successfully.
 608
 609 **/
 610 EFI_STATUS
 611 EFIAPI
 612 VariableServiceQueryVariableInfoInternal (
 613   IN  UINT32                 Attributes,
 614   OUT UINT64                 *MaximumVariableStorageSize,
 615   OUT UINT64                 *RemainingVariableStorageSize,
 616   OUT UINT64                 *MaximumVariableSize
 617   );
 618
 619 /**
 620
 621   This code returns information about the EFI variables.
 622
 623   Caution: This function may receive untrusted input.
 624   This function may be invoked in SMM mode. This function will do basic validation, before parse the data.
 625
 626   @param Attributes                     Attributes bitmask to specify the type of variables
 627                                         on which to return information.
 628   @param MaximumVariableStorageSize     Pointer to the maximum size of the storage space available
 629                                         for the EFI variables associated with the attributes specified.
 630   @param RemainingVariableStorageSize   Pointer to the remaining size of the storage space available
 631                                         for EFI variables associated with the attributes specified.
 632   @param MaximumVariableSize            Pointer to the maximum size of an individual EFI variables
 633                                         associated with the attributes specified.
 634
 635   @return EFI_INVALID_PARAMETER         An invalid combination of attribute bits was supplied.
 636   @return EFI_SUCCESS                   Query successfully.
 637   @return EFI_UNSUPPORTED               The attribute is not supported on this platform.
 638
 639 **/
 640 EFI_STATUS
 641 EFIAPI
 642 VariableServiceQueryVariableInfo (
 643   IN  UINT32                 Attributes,
 644   OUT UINT64                 *MaximumVariableStorageSize,
 645   OUT UINT64                 *RemainingVariableStorageSize,
 646   OUT UINT64                 *MaximumVariableSize
 647   );
 648
 649 /**
 650   Mark a variable that will become read-only after leaving the DXE phase of execution.
 651
 652   @param[in] This          The VARIABLE_LOCK_PROTOCOL instance.
 653   @param[in] VariableName  A pointer to the variable name that will be made read-only subsequently.
 654   @param[in] VendorGuid    A pointer to the vendor GUID that will be made read-only subsequently.
 655
 656   @retval EFI_SUCCESS           The variable specified by the VariableName and the VendorGuid was marked
 657                                 as pending to be read-only.
 658   @retval EFI_INVALID_PARAMETER VariableName or VendorGuid is NULL.
 659                                 Or VariableName is an empty string.
 660   @retval EFI_ACCESS_DENIED     EFI_END_OF_DXE_EVENT_GROUP_GUID or EFI_EVENT_GROUP_READY_TO_BOOT has
 661                                 already been signaled.
 662   @retval EFI_OUT_OF_RESOURCES  There is not enough resource to hold the lock request.
 663 **/
 664 EFI_STATUS
 665 EFIAPI
 666 VariableLockRequestToLock (
 667   IN CONST EDKII_VARIABLE_LOCK_PROTOCOL *This,
 668   IN       CHAR16                       *VariableName,
 669   IN       EFI_GUID                     *VendorGuid
 670   );
 671
 672 extern VARIABLE_MODULE_GLOBAL  *mVariableModuleGlobal;
 673
 674 #endif