SecurityPkg/Tcg/Tcg2Smm/Tcg2StandaloneMm.c

   1 /** @file
   2   TCG2 Standalone MM 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/StandaloneMmMemLib.h>
  20
  21 /**
  22   Notify the system that the SMM variable driver is ready.
  23 **/
  24 VOID
  25 Tcg2NotifyMmReady (
  26   VOID
  27   )
  28 {
  29   // Do nothing
  30 }
  31
  32 /**
  33   This function is an abstraction layer for implementation specific Mm buffer validation routine.
  34
  35   @param Buffer  The buffer start address to be checked.
  36   @param Length  The buffer length to be checked.
  37
  38   @retval TRUE  This buffer is valid per processor architecture and not overlap with SMRAM.
  39   @retval FALSE This buffer is not valid per processor architecture or overlap with SMRAM.
  40 **/
  41 BOOLEAN
  42 IsBufferOutsideMmValid (
  43   IN EFI_PHYSICAL_ADDRESS  Buffer,
  44   IN UINT64                Length
  45   )
  46 {
  47   return MmIsBufferOutsideMmValid (Buffer, Length);
  48 }
  49
  50 /**
  51   The driver's entry point.
  52
  53   It install callbacks for TPM physical presence and MemoryClear, and locate
  54   SMM variable to be used in the callback function.
  55
  56   @param[in] ImageHandle  The firmware allocated handle for the EFI image.
  57   @param[in] SystemTable  A pointer to the EFI System Table.
  58
  59   @retval EFI_SUCCESS     The entry point is executed successfully.
  60   @retval Others          Some error occurs when executing this entry point.
  61
  62 **/
  63 EFI_STATUS
  64 EFIAPI
  65 InitializeTcgStandaloneMm (
  66   IN EFI_HANDLE           ImageHandle,
  67   IN EFI_MM_SYSTEM_TABLE  *SystemTable
  68   )
  69 {
  70   return InitializeTcgCommon ();
  71 }