SecurityPkg/VariableAuthenticated/Pei/Variable.h

   1 /** @file
   2   The internal header file includes the common header files, defines
   3   internal structure and functions used by PeiVariable module.
   4
   5 Copyright (c) 2009 - 2013, 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 _PEI_VARIABLE_H_
  17 #define _PEI_VARIABLE_H_
  18
  19 #include <PiPei.h>
  20 #include <Ppi/ReadOnlyVariable2.h>
  21
  22 #include <Library/DebugLib.h>
  23 #include <Library/PeimEntryPoint.h>
  24 #include <Library/HobLib.h>
  25 #include <Library/PcdLib.h>
  26 #include <Library/BaseMemoryLib.h>
  27 #include <Library/PeiServicesTablePointerLib.h>
  28 #include <Library/PeiServicesLib.h>
  29
  30 #include <Guid/AuthenticatedVariableFormat.h>
  31 #include <Guid/VariableIndexTable.h>
  32 #include <Guid/SystemNvDataGuid.h>
  33 #include <Guid/FaultTolerantWrite.h>
  34
  35 typedef enum {
  36   VariableStoreTypeHob,
  37   VariableStoreTypeNv,
  38   VariableStoreTypeMax
  39 } VARIABLE_STORE_TYPE;
  40
  41 typedef struct {
  42   VARIABLE_STORE_HEADER                   *VariableStoreHeader;
  43   VARIABLE_INDEX_TABLE                    *IndexTable;
  44   //
  45   // If it is not NULL, it means there may be an inconsecutive variable whose
  46   // partial content is still in NV storage, but another partial content is backed up
  47   // in spare block.
  48   //
  49   FAULT_TOLERANT_WRITE_LAST_WRITE_DATA    *FtwLastWriteData;
  50 } VARIABLE_STORE_INFO;
  51
  52 //
  53 // Functions
  54 //
  55 /**
  56   Provide the functionality of the variable services.
  57
  58   @param  FileHandle  Handle of the file being invoked.
  59                       Type EFI_PEI_FILE_HANDLE is defined in FfsFindNextFile().
  60   @param  PeiServices  General purpose services available to every PEIM.
  61
  62   @retval EFI_SUCCESS  If the interface could be successfully installed
  63   @retval Others       Returned from PeiServicesInstallPpi()
  64
  65 **/
  66 EFI_STATUS
  67 EFIAPI
  68 PeimInitializeVariableServices (
  69   IN       EFI_PEI_FILE_HANDLE       FileHandle,
  70   IN CONST EFI_PEI_SERVICES          **PeiServices
  71   );
  72
  73 /**
  74   This service retrieves a variable's value using its name and GUID.
  75
  76   Read the specified variable from the UEFI variable store. If the Data
  77   buffer is too small to hold the contents of the variable, the error
  78   EFI_BUFFER_TOO_SMALL is returned and DataSize is set to the required buffer
  79   size to obtain the data.
  80
  81   @param  This                  A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
  82   @param  VariableName          A pointer to a null-terminated string that is the variable's name.
  83   @param  VariableGuid          A pointer to an EFI_GUID that is the variable's GUID. The combination of
  84                                 VariableGuid and VariableName must be unique.
  85   @param  Attributes            If non-NULL, on return, points to the variable's attributes.
  86   @param  DataSize              On entry, points to the size in bytes of the Data buffer.
  87                                 On return, points to the size of the data returned in Data.
  88   @param  Data                  Points to the buffer which will hold the returned variable value.
  89
  90   @retval EFI_SUCCESS           The variable was read successfully.
  91   @retval EFI_NOT_FOUND         The variable could not be found.
  92   @retval EFI_BUFFER_TOO_SMALL  The DataSize is too small for the resulting data.
  93                                 DataSize is updated with the size required for
  94                                 the specified variable.
  95   @retval EFI_INVALID_PARAMETER VariableName, VariableGuid, DataSize or Data is NULL.
  96   @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
  97
  98 **/
  99 EFI_STATUS
 100 EFIAPI
 101 PeiGetVariable (
 102   IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI *This,
 103   IN CONST  CHAR16                          *VariableName,
 104   IN CONST  EFI_GUID                        *VariableGuid,
 105   OUT       UINT32                          *Attributes,
 106   IN OUT    UINTN                           *DataSize,
 107   OUT       VOID                            *Data
 108   );
 109
 110 /**
 111   Return the next variable name and GUID.
 112
 113   This function is called multiple times to retrieve the VariableName
 114   and VariableGuid of all variables currently available in the system.
 115   On each call, the previous results are passed into the interface,
 116   and, on return, the interface returns the data for the next
 117   interface. When the entire variable list has been returned,
 118   EFI_NOT_FOUND is returned.
 119
 120   @param  This              A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
 121
 122   @param  VariableNameSize  On entry, points to the size of the buffer pointed to by VariableName.
 123   @param  VariableName      On entry, a pointer to a null-terminated string that is the variable's name.
 124                             On return, points to the next variable's null-terminated name string.
 125
 126   @param  VariableGuid      On entry, a pointer to an UEFI _GUID that is the variable's GUID.
 127                             On return, a pointer to the next variable's GUID.
 128
 129   @retval EFI_SUCCESS           The variable was read successfully.
 130   @retval EFI_NOT_FOUND         The variable could not be found.
 131   @retval EFI_BUFFER_TOO_SMALL  The VariableNameSize is too small for the resulting
 132                                 data. VariableNameSize is updated with the size
 133                                 required for the specified variable.
 134   @retval EFI_INVALID_PARAMETER VariableName, VariableGuid or
 135                                 VariableNameSize is NULL.
 136   @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
 137
 138 **/
 139 EFI_STATUS
 140 EFIAPI
 141 PeiGetNextVariableName (
 142   IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI *This,
 143   IN OUT UINTN                              *VariableNameSize,
 144   IN OUT CHAR16                             *VariableName,
 145   IN OUT EFI_GUID                           *VariableGuid
 146   );
 147
 148 #endif