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
VariableSmmIsBufferOutsideSmmValid(IN EFI_PHYSICAL_ADDRESS Buffer,IN UINT64 Length)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
VariableNotifySmmReady(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
VariableNotifySmmWriteReady(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
VariableServiceInitialize(IN EFI_HANDLE ImageHandle,IN EFI_SYSTEM_TABLE * SystemTable)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
VariableHaveTcgProtocols(VOID)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 }
131