MdeModulePkg/Universal/Variable/RuntimeDxe/VariableTraditionalMm.c

   1 /** @file
   2
   3   Parts of the SMM/MM implementation that are specific to traditional MM
   4
   5 Copyright (c) 2011 - 2018, Intel Corporation. All rights reserved. <BR>
   6 Copyright (c) 2018, Linaro, Ltd. All rights reserved. <BR>
   7 This program and the accompanying materials
   8 are licensed and made available under the terms and conditions of the BSD License
   9 which accompanies this distribution.  The full text of the license may be found at
  10 http://opensource.org/licenses/bsd-license.php
  11
  12 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15 **/
  16
  17 #include <Library/UefiBootServicesTableLib.h>
  18 #include <Library/SmmMemLib.h>
  19 #include "Variable.h"
  20
  21 /**
  22   This function checks if the buffer is valid per processor architecture and
  23   does not overlap with SMRAM.
  24
  25   @param Buffer The buffer start address to be checked.
  26   @param Length The buffer length to be checked.
  27
  28   @retval TRUE  This buffer is valid per processor architecture and does not
  29                 overlap with SMRAM.
  30   @retval FALSE This buffer is not valid per processor architecture or overlaps
  31                 with SMRAM.
  32 **/
  33 BOOLEAN
  34 VariableSmmIsBufferOutsideSmmValid (
  35   IN EFI_PHYSICAL_ADDRESS  Buffer,
  36   IN UINT64                Length
  37   )
  38 {
  39   return SmmIsBufferOutsideSmmValid (Buffer, Length);
  40 }
  41
  42 /**
  43   Notify the system that the SMM variable driver is ready.
  44 **/
  45 VOID
  46 VariableNotifySmmReady (
  47   VOID
  48   )
  49 {
  50   EFI_STATUS            Status;
  51   EFI_HANDLE            Handle;
  52
  53   Handle = NULL;
  54   Status = gBS->InstallProtocolInterface (
  55                   &Handle,
  56                   &gEfiSmmVariableProtocolGuid,
  57                   EFI_NATIVE_INTERFACE,
  58                   NULL
  59                   );
  60   ASSERT_EFI_ERROR (Status);
  61 }
  62
  63 /**
  64   Notify the system that the SMM variable write driver is ready.
  65 **/
  66 VOID
  67 VariableNotifySmmWriteReady (
  68   VOID
  69   )
  70 {
  71   EFI_STATUS            Status;
  72   EFI_HANDLE            Handle;
  73
  74   Handle = NULL;
  75   Status = gBS->InstallProtocolInterface (
  76                   &Handle,
  77                   &gSmmVariableWriteGuid,
  78                   EFI_NATIVE_INTERFACE,
  79                   NULL
  80                   );
  81   ASSERT_EFI_ERROR (Status);
  82 }
  83
  84 /**
  85   Variable service MM driver entry point
  86
  87   @param[in] ImageHandle    A handle for the image that is initializing this
  88                             driver
  89   @param[in] SystemTable    A pointer to the EFI system table
  90
  91   @retval EFI_SUCCESS       Variable service successfully initialized.
  92 **/
  93 EFI_STATUS
  94 EFIAPI
  95 VariableServiceInitialize (
  96   IN EFI_HANDLE                           ImageHandle,
  97   IN EFI_SYSTEM_TABLE                     *SystemTable
  98   )
  99 {
 100   return MmVariableServiceInitialize ();
 101 }
 102
 103 /**
 104   Whether the TCG or TCG2 protocols are installed in the UEFI protocol database.
 105   This information is used by the MorLock code to infer whether an existing
 106   MOR variable is legitimate or not.
 107
 108   @retval TRUE  Either the TCG or TCG2 protocol is installed in the UEFI
 109                 protocol database
 110   @retval FALSE Neither the TCG nor the TCG2 protocol is installed in the UEFI
 111                 protocol database
 112 **/
 113 BOOLEAN
 114 VariableHaveTcgProtocols (
 115   VOID
 116   )
 117 {
 118   EFI_STATUS            Status;
 119   VOID                  *Interface;
 120
 121   Status = gBS->LocateProtocol (
 122                   &gEfiTcg2ProtocolGuid,
 123                   NULL,                     // Registration
 124                   &Interface
 125                   );
 126   if (!EFI_ERROR (Status)) {
 127     return TRUE;
 128   }
 129
 130   Status = gBS->LocateProtocol (
 131                   &gEfiTcgProtocolGuid,
 132                   NULL,                     // Registration
 133                   &Interface
 134                   );
 135   return !EFI_ERROR (Status);
 136 }