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 SPDX-License-Identifier: BSD-2-Clause-Patent
   8
   9 **/
  10
  11 #include <Library/UefiBootServicesTableLib.h>
  12 #include <Library/SmmMemLib.h>
  13 #include "Variable.h"
  14
  15 /**
  16   This function checks if the buffer is valid per processor architecture and
  17   does not overlap with SMRAM.
  18
  19   @param Buffer The buffer start address to be checked.
  20   @param Length The buffer length to be checked.
  21
  22   @retval TRUE  This buffer is valid per processor architecture and does not
  23                 overlap with SMRAM.
  24   @retval FALSE This buffer is not valid per processor architecture or overlaps
  25                 with SMRAM.
  26 **/
  27 BOOLEAN
  28 VariableSmmIsBufferOutsideSmmValid (
  29   IN EFI_PHYSICAL_ADDRESS  Buffer,
  30   IN UINT64                Length
  31   )
  32 {
  33   return SmmIsBufferOutsideSmmValid (Buffer, Length);
  34 }
  35
  36 /**
  37   Notify the system that the SMM variable driver is ready.
  38 **/
  39 VOID
  40 VariableNotifySmmReady (
  41   VOID
  42   )
  43 {
  44   EFI_STATUS            Status;
  45   EFI_HANDLE            Handle;
  46
  47   Handle = NULL;
  48   Status = gBS->InstallProtocolInterface (
  49                   &Handle,
  50                   &gEfiSmmVariableProtocolGuid,
  51                   EFI_NATIVE_INTERFACE,
  52                   NULL
  53                   );
  54   ASSERT_EFI_ERROR (Status);
  55 }
  56
  57 /**
  58   Notify the system that the SMM variable write driver is ready.
  59 **/
  60 VOID
  61 VariableNotifySmmWriteReady (
  62   VOID
  63   )
  64 {
  65   EFI_STATUS            Status;
  66   EFI_HANDLE            Handle;
  67
  68   Handle = NULL;
  69   Status = gBS->InstallProtocolInterface (
  70                   &Handle,
  71                   &gSmmVariableWriteGuid,
  72                   EFI_NATIVE_INTERFACE,
  73                   NULL
  74                   );
  75   ASSERT_EFI_ERROR (Status);
  76 }
  77
  78 /**
  79   Variable service MM driver entry point
  80
  81   @param[in] ImageHandle    A handle for the image that is initializing this
  82                             driver
  83   @param[in] SystemTable    A pointer to the EFI system table
  84
  85   @retval EFI_SUCCESS       Variable service successfully initialized.
  86 **/
  87 EFI_STATUS
  88 EFIAPI
  89 VariableServiceInitialize (
  90   IN EFI_HANDLE                           ImageHandle,
  91   IN EFI_SYSTEM_TABLE                     *SystemTable
  92   )
  93 {
  94   return MmVariableServiceInitialize ();
  95 }
  96
  97 /**
  98   Whether the TCG or TCG2 protocols are installed in the UEFI protocol database.
  99   This information is used by the MorLock code to infer whether an existing
 100   MOR variable is legitimate or not.
 101
 102   @retval TRUE  Either the TCG or TCG2 protocol is installed in the UEFI
 103                 protocol database
 104   @retval FALSE Neither the TCG nor the TCG2 protocol is installed in the UEFI
 105                 protocol database
 106 **/
 107 BOOLEAN
 108 VariableHaveTcgProtocols (
 109   VOID
 110   )
 111 {
 112   EFI_STATUS            Status;
 113   VOID                  *Interface;
 114
 115   Status = gBS->LocateProtocol (
 116                   &gEfiTcg2ProtocolGuid,
 117                   NULL,                     // Registration
 118                   &Interface
 119                   );
 120   if (!EFI_ERROR (Status)) {
 121     return TRUE;
 122   }
 123
 124   Status = gBS->LocateProtocol (
 125                   &gEfiTcgProtocolGuid,
 126                   NULL,                     // Registration
 127                   &Interface
 128                   );
 129   return !EFI_ERROR (Status);
 130 }