SecurityPkg/Tcg/Tcg2Smm/Tcg2TraditionalMm.c

   1 /** @file
   2   TCG2 SMM driver that updates TPM2 items in ACPI table and registers
   3   SMI2 callback functions for Tcg2 physical presence, ClearMemory, and
   4   sample for dTPM StartMethod.
   5
   6   Caution: This module requires additional review when modified.
   7   This driver will have external input - variable and ACPINvs data in SMM mode.
   8   This external input must be validated carefully to avoid security issue.
   9
  10   PhysicalPresenceCallback() and MemoryClearCallback() will receive untrusted input and do some check.
  11
  12 Copyright (c) 2015 - 2018, Intel Corporation. All rights reserved.<BR>
  13 Copyright (c) Microsoft Corporation.
  14 SPDX-License-Identifier: BSD-2-Clause-Patent
  15
  16 **/
  17
  18 #include "Tcg2Smm.h"
  19 #include <Library/UefiBootServicesTableLib.h>
  20 #include <Library/SmmMemLib.h>
  21
  22 /**
  23   Notify the system that the SMM variable driver is ready.
  24 **/
  25 VOID
  26 Tcg2NotifyMmReady (
  27   VOID
  28   )
  29 {
  30   EFI_STATUS  Status;
  31   EFI_HANDLE  Handle;
  32
  33   Handle = NULL;
  34   Status = gBS->InstallProtocolInterface (
  35                   &Handle,
  36                   &gTcg2MmSwSmiRegisteredGuid,
  37                   EFI_NATIVE_INTERFACE,
  38                   NULL
  39                   );
  40   ASSERT_EFI_ERROR (Status);
  41 }
  42
  43 /**
  44   This function is an abstraction layer for implementation specific Mm buffer validation routine.
  45
  46   @param Buffer  The buffer start address to be checked.
  47   @param Length  The buffer length to be checked.
  48
  49   @retval TRUE  This buffer is valid per processor architecture and not overlap with SMRAM.
  50   @retval FALSE This buffer is not valid per processor architecture or overlap with SMRAM.
  51 **/
  52 BOOLEAN
  53 IsBufferOutsideMmValid (
  54   IN EFI_PHYSICAL_ADDRESS  Buffer,
  55   IN UINT64                Length
  56   )
  57 {
  58   return SmmIsBufferOutsideSmmValid (Buffer, Length);
  59 }
  60
  61 /**
  62   The driver's entry point.
  63
  64   It install callbacks for TPM physical presence and MemoryClear, and locate
  65   SMM variable to be used in the callback function.
  66
  67   @param[in] ImageHandle  The firmware allocated handle for the EFI image.
  68   @param[in] SystemTable  A pointer to the EFI System Table.
  69
  70   @retval EFI_SUCCESS     The entry point is executed successfully.
  71   @retval Others          Some error occurs when executing this entry point.
  72
  73 **/
  74 EFI_STATUS
  75 EFIAPI
  76 InitializeTcgSmm (
  77   IN EFI_HANDLE        ImageHandle,
  78   IN EFI_SYSTEM_TABLE  *SystemTable
  79   )
  80 {
  81   return InitializeTcgCommon ();
  82 }