MdeModulePkg/Universal/Variable/RuntimeDxe/VariableLockRequestToLock.c

   1 /** @file
   2   Temporary location of the RequestToLock shim code while projects
   3   are moved to VariablePolicy. Should be removed when deprecated.
   4
   5   Copyright (c) Microsoft Corporation.
   6   SPDX-License-Identifier: BSD-2-Clause-Patent
   7
   8 **/
   9
  10 #include <Uefi.h>
  11 #include <Library/DebugLib.h>
  12 #include <Library/MemoryAllocationLib.h>
  13 #include <Library/VariablePolicyLib.h>
  14 #include <Library/VariablePolicyHelperLib.h>
  15 #include <Protocol/VariableLock.h>
  16
  17 /**
  18   DEPRECATED. THIS IS ONLY HERE AS A CONVENIENCE WHILE PORTING.
  19   Mark a variable that will become read-only after leaving the DXE phase of
  20   execution. Write request coming from SMM environment through
  21   EFI_SMM_VARIABLE_PROTOCOL is allowed.
  22
  23   @param[in] This          The VARIABLE_LOCK_PROTOCOL instance.
  24   @param[in] VariableName  A pointer to the variable name that will be made
  25                            read-only subsequently.
  26   @param[in] VendorGuid    A pointer to the vendor GUID that will be made
  27                            read-only subsequently.
  28
  29   @retval EFI_SUCCESS           The variable specified by the VariableName and
  30                                 the VendorGuid was marked as pending to be
  31                                 read-only.
  32   @retval EFI_INVALID_PARAMETER VariableName or VendorGuid is NULL.
  33                                 Or VariableName is an empty string.
  34   @retval EFI_ACCESS_DENIED     EFI_END_OF_DXE_EVENT_GROUP_GUID or
  35                                 EFI_EVENT_GROUP_READY_TO_BOOT has already been
  36                                 signaled.
  37   @retval EFI_OUT_OF_RESOURCES  There is not enough resource to hold the lock
  38                                 request.
  39 **/
  40 EFI_STATUS
  41 EFIAPI
  42 VariableLockRequestToLock (
  43   IN CONST EDKII_VARIABLE_LOCK_PROTOCOL  *This,
  44   IN CHAR16                              *VariableName,
  45   IN EFI_GUID                            *VendorGuid
  46   )
  47 {
  48   EFI_STATUS             Status;
  49   VARIABLE_POLICY_ENTRY  *NewPolicy;
  50
  51   DEBUG ((DEBUG_WARN, "!!! DEPRECATED INTERFACE !!! %a() will go away soon!\n", __FUNCTION__));
  52   DEBUG ((DEBUG_WARN, "!!! DEPRECATED INTERFACE !!! Please move to use Variable Policy!\n"));
  53   DEBUG ((DEBUG_WARN, "!!! DEPRECATED INTERFACE !!! Variable: %g %s\n", VendorGuid, VariableName));
  54
  55   NewPolicy = NULL;
  56   Status = CreateBasicVariablePolicy(
  57              VendorGuid,
  58              VariableName,
  59              VARIABLE_POLICY_NO_MIN_SIZE,
  60              VARIABLE_POLICY_NO_MAX_SIZE,
  61              VARIABLE_POLICY_NO_MUST_ATTR,
  62              VARIABLE_POLICY_NO_CANT_ATTR,
  63              VARIABLE_POLICY_TYPE_LOCK_NOW,
  64              &NewPolicy
  65              );
  66   if (!EFI_ERROR( Status )) {
  67     Status = RegisterVariablePolicy (NewPolicy);
  68
  69     //
  70     // If the error returned is EFI_ALREADY_STARTED, we need to check the
  71     // current database for the variable and see whether it's locked. If it's
  72     // locked, we're still fine, but also generate a DEBUG_WARN message so the
  73     // duplicate lock can be removed.
  74     //
  75     if (Status == EFI_ALREADY_STARTED) {
  76       Status = ValidateSetVariable (VariableName, VendorGuid, 0, 0, NULL);
  77       if (Status == EFI_WRITE_PROTECTED) {
  78         DEBUG ((DEBUG_WARN, "  Variable: %g %s is already locked!\n", VendorGuid, VariableName));
  79         Status = EFI_SUCCESS;
  80       } else {
  81         DEBUG ((DEBUG_ERROR, "  Variable: %g %s can not be locked!\n", VendorGuid, VariableName));
  82         Status = EFI_ACCESS_DENIED;
  83       }
  84     }
  85   }
  86   if (EFI_ERROR (Status)) {
  87     DEBUG(( DEBUG_ERROR, "%a - Failed to lock variable %s! %r\n", __FUNCTION__, VariableName, Status ));
  88   }
  89   if (NewPolicy != NULL) {
  90     FreePool( NewPolicy );
  91   }
  92
  93   return Status;
  94 }