MdeModulePkg/Universal/SecurityStubDxe/SecurityStub.c

   1 /** @file
   2   This driver implements one sample platform security service, which does
   3   nothing and always return EFI_SUCCESS.
   4
   5   Copyright (c) 2006 - 2008, Intel Corporation
   6   All rights reserved. This program and the accompanying materials
   7   are licensed and made available under the terms and conditions of the BSD License
   8   which accompanies this distribution.  The full text of the license may be found at
   9   http://opensource.org/licenses/bsd-license.php
  10
  11   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  12   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  13
  14 **/
  15
  16
  17 #include "SecurityStub.h"
  18
  19 //
  20 // Handle for the Security Architectural Protocol instance produced by this driver
  21 //
  22 EFI_HANDLE                  mSecurityArchProtocolHandle = NULL;
  23
  24 //
  25 // Security Architectural Protocol instance produced by this driver
  26 //
  27 EFI_SECURITY_ARCH_PROTOCOL  mSecurityStub = {
  28   SecurityStubAuthenticateState
  29 };
  30
  31
  32 /**
  33   The EFI_SECURITY_ARCH_PROTOCOL (SAP) is used to abstract platform-specific
  34   policy from the DXE core response to an attempt to use a file that returns a
  35   given status for the authentication check from the section extraction protocol.
  36
  37   The possible responses in a given SAP implementation may include locking
  38   flash upon failure to authenticate, attestation logging for all signed drivers,
  39   and other exception operations.  The File parameter allows for possible logging
  40   within the SAP of the driver.
  41
  42   If File is NULL, then EFI_INVALID_PARAMETER is returned.
  43
  44   If the file specified by File with an authentication status specified by
  45   AuthenticationStatus is safe for the DXE Core to use, then EFI_SUCCESS is returned.
  46
  47   If the file specified by File with an authentication status specified by
  48   AuthenticationStatus is not safe for the DXE Core to use under any circumstances,
  49   then EFI_ACCESS_DENIED is returned.
  50
  51   If the file specified by File with an authentication status specified by
  52   AuthenticationStatus is not safe for the DXE Core to use right now, but it
  53   might be possible to use it at a future time, then EFI_SECURITY_VIOLATION is
  54   returned.
  55
  56   @param  This             The EFI_SECURITY_ARCH_PROTOCOL instance.
  57   @param  AuthenticationStatus
  58                            This is the authentication type returned from the Section
  59                            Extraction protocol. See the Section Extraction Protocol
  60                            Specification for details on this type.
  61   @param  File             This is a pointer to the device path of the file that is
  62                            being dispatched. This will optionally be used for logging.
  63
  64   @retval EFI_SUCCESS            Do nothing and return.
  65   @retval EFI_INVALID_PARAMETER  File is NULL.
  66 **/
  67 EFI_STATUS
  68 EFIAPI
  69 SecurityStubAuthenticateState (
  70   IN CONST EFI_SECURITY_ARCH_PROTOCOL  *This,
  71   IN UINT32                            AuthenticationStatus,
  72   IN CONST EFI_DEVICE_PATH_PROTOCOL    *File
  73   )
  74 {
  75   if (File == NULL) {
  76     return EFI_INVALID_PARAMETER;
  77   }
  78
  79   return EFI_SUCCESS;
  80 }
  81
  82
  83 /**
  84   The user Entry Point installs SAP. The user code starts with this function
  85   as the real entry point for the image goes into a library that calls this
  86   function.
  87
  88   @param ImageHandle    The firmware allocated handle for the EFI image.
  89   @param SystemTable    A pointer to the EFI System Table.
  90
  91   @retval EFI_SUCCESS   Install the sample Security Architectural Protocol successfully.
  92
  93 **/
  94 EFI_STATUS
  95 EFIAPI
  96 SecurityStubInitialize (
  97   IN EFI_HANDLE        ImageHandle,
  98   IN EFI_SYSTEM_TABLE  *SystemTable
  99   )
 100 {
 101   EFI_STATUS  Status;
 102
 103   //
 104   // Make sure the Security Architectural Protocol is not already installed in the system
 105   //
 106   ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gEfiSecurityArchProtocolGuid);
 107
 108   //
 109   // Install the Security Architectural Protocol onto a new handle
 110   //
 111   Status = gBS->InstallMultipleProtocolInterfaces (
 112                   &mSecurityArchProtocolHandle,
 113                   &gEfiSecurityArchProtocolGuid,
 114                   &mSecurityStub,
 115                   NULL
 116                   );
 117   ASSERT_EFI_ERROR (Status);
 118
 119   return EFI_SUCCESS;
 120 }