MdeModulePkg/Universal/Variable/RuntimeDxe/VarCheck.c

   1 /** @file
   2   Implementation functions and structures for var check protocol
   3   and variable lock protocol based on VarCheckLib.
   4
   5 Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
   6 SPDX-License-Identifier: BSD-2-Clause-Patent
   7
   8 **/
   9
  10 #include "Variable.h"
  11
  12 /**
  13   Mark a variable that will become read-only after leaving the DXE phase of execution.
  14   Write request coming from SMM environment through EFI_SMM_VARIABLE_PROTOCOL is allowed.
  15
  16   @param[in] This          The VARIABLE_LOCK_PROTOCOL instance.
  17   @param[in] VariableName  A pointer to the variable name that will be made read-only subsequently.
  18   @param[in] VendorGuid    A pointer to the vendor GUID that will be made read-only subsequently.
  19
  20   @retval EFI_SUCCESS           The variable specified by the VariableName and the VendorGuid was marked
  21                                 as pending to be read-only.
  22   @retval EFI_INVALID_PARAMETER VariableName or VendorGuid is NULL.
  23                                 Or VariableName is an empty string.
  24   @retval EFI_ACCESS_DENIED     EFI_END_OF_DXE_EVENT_GROUP_GUID or EFI_EVENT_GROUP_READY_TO_BOOT has
  25                                 already been signaled.
  26   @retval EFI_OUT_OF_RESOURCES  There is not enough resource to hold the lock request.
  27 **/
  28 EFI_STATUS
  29 EFIAPI
  30 VariableLockRequestToLock (
  31   IN CONST EDKII_VARIABLE_LOCK_PROTOCOL *This,
  32   IN       CHAR16                       *VariableName,
  33   IN       EFI_GUID                     *VendorGuid
  34   )
  35 {
  36   EFI_STATUS                    Status;
  37   VAR_CHECK_VARIABLE_PROPERTY   Property;
  38
  39   AcquireLockOnlyAtBootTime (&mVariableModuleGlobal->VariableGlobal.VariableServicesLock);
  40
  41   Status = VarCheckLibVariablePropertyGet (VariableName, VendorGuid, &Property);
  42   if (!EFI_ERROR (Status)) {
  43     Property.Property |= VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY;
  44   } else {
  45     Property.Revision = VAR_CHECK_VARIABLE_PROPERTY_REVISION;
  46     Property.Property = VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY;
  47     Property.Attributes = 0;
  48     Property.MinSize = 1;
  49     Property.MaxSize = MAX_UINTN;
  50   }
  51   Status = VarCheckLibVariablePropertySet (VariableName, VendorGuid, &Property);
  52
  53   DEBUG ((EFI_D_INFO, "[Variable] Lock: %g:%s %r\n", VendorGuid, VariableName, Status));
  54
  55   ReleaseLockOnlyAtBootTime (&mVariableModuleGlobal->VariableGlobal.VariableServicesLock);
  56
  57   return Status;
  58 }
  59
  60 /**
  61   Register SetVariable check handler.
  62
  63   @param[in] Handler            Pointer to check handler.
  64
  65   @retval EFI_SUCCESS           The SetVariable check handler was registered successfully.
  66   @retval EFI_INVALID_PARAMETER Handler is NULL.
  67   @retval EFI_ACCESS_DENIED     EFI_END_OF_DXE_EVENT_GROUP_GUID or EFI_EVENT_GROUP_READY_TO_BOOT has
  68                                 already been signaled.
  69   @retval EFI_OUT_OF_RESOURCES  There is not enough resource for the SetVariable check handler register request.
  70   @retval EFI_UNSUPPORTED       This interface is not implemented.
  71                                 For example, it is unsupported in VarCheck protocol if both VarCheck and SmmVarCheck protocols are present.
  72
  73 **/
  74 EFI_STATUS
  75 EFIAPI
  76 VarCheckRegisterSetVariableCheckHandler (
  77   IN VAR_CHECK_SET_VARIABLE_CHECK_HANDLER   Handler
  78   )
  79 {
  80   EFI_STATUS    Status;
  81
  82   AcquireLockOnlyAtBootTime (&mVariableModuleGlobal->VariableGlobal.VariableServicesLock);
  83   Status = VarCheckLibRegisterSetVariableCheckHandler (Handler);
  84   ReleaseLockOnlyAtBootTime (&mVariableModuleGlobal->VariableGlobal.VariableServicesLock);
  85
  86   return Status;
  87 }
  88
  89 /**
  90   Variable property set.
  91
  92   @param[in] Name               Pointer to the variable name.
  93   @param[in] Guid               Pointer to the vendor GUID.
  94   @param[in] VariableProperty   Pointer to the input variable property.
  95
  96   @retval EFI_SUCCESS           The property of variable specified by the Name and Guid was set successfully.
  97   @retval EFI_INVALID_PARAMETER Name, Guid or VariableProperty is NULL, or Name is an empty string,
  98                                 or the fields of VariableProperty are not valid.
  99   @retval EFI_ACCESS_DENIED     EFI_END_OF_DXE_EVENT_GROUP_GUID or EFI_EVENT_GROUP_READY_TO_BOOT has
 100                                 already been signaled.
 101   @retval EFI_OUT_OF_RESOURCES  There is not enough resource for the variable property set request.
 102
 103 **/
 104 EFI_STATUS
 105 EFIAPI
 106 VarCheckVariablePropertySet (
 107   IN CHAR16                         *Name,
 108   IN EFI_GUID                       *Guid,
 109   IN VAR_CHECK_VARIABLE_PROPERTY    *VariableProperty
 110   )
 111 {
 112   EFI_STATUS    Status;
 113
 114   AcquireLockOnlyAtBootTime (&mVariableModuleGlobal->VariableGlobal.VariableServicesLock);
 115   Status = VarCheckLibVariablePropertySet (Name, Guid, VariableProperty);
 116   ReleaseLockOnlyAtBootTime (&mVariableModuleGlobal->VariableGlobal.VariableServicesLock);
 117
 118   return Status;
 119 }
 120
 121 /**
 122   Variable property get.
 123
 124   @param[in]  Name              Pointer to the variable name.
 125   @param[in]  Guid              Pointer to the vendor GUID.
 126   @param[out] VariableProperty  Pointer to the output variable property.
 127
 128   @retval EFI_SUCCESS           The property of variable specified by the Name and Guid was got successfully.
 129   @retval EFI_INVALID_PARAMETER Name, Guid or VariableProperty is NULL, or Name is an empty string.
 130   @retval EFI_NOT_FOUND         The property of variable specified by the Name and Guid was not found.
 131
 132 **/
 133 EFI_STATUS
 134 EFIAPI
 135 VarCheckVariablePropertyGet (
 136   IN CHAR16                         *Name,
 137   IN EFI_GUID                       *Guid,
 138   OUT VAR_CHECK_VARIABLE_PROPERTY   *VariableProperty
 139   )
 140 {
 141   EFI_STATUS    Status;
 142
 143   AcquireLockOnlyAtBootTime (&mVariableModuleGlobal->VariableGlobal.VariableServicesLock);
 144   Status = VarCheckLibVariablePropertyGet (Name, Guid, VariableProperty);
 145   ReleaseLockOnlyAtBootTime (&mVariableModuleGlobal->VariableGlobal.VariableServicesLock);
 146
 147   return Status;
 148 }
 149