1 /** @file
2 Boot Script Helper SMM driver.
3
4 This driver is responsible to store BootScriptThunk from ReservedMemory to SMRAM for security consideration.
5
6 Copyright (c) 2010 - 2012, Intel Corporation. All rights reserved.<BR>
7
8 This program and the accompanying materials
9 are licensed and made available under the terms and conditions
10 of the BSD License which accompanies this distribution. The
11 full text of the license may be found at
12 http://opensource.org/licenses/bsd-license.php
13
14 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
15 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
16
17 **/
18
19 #include <PiDxe.h>
20 #include <Library/BaseLib.h>
21 #include <Library/PcdLib.h>
22 #include <Library/DebugLib.h>
23 #include <Library/LockBoxLib.h>
24
25 #include <Guid/BootScriptThunkData.h>
26
27 EFI_GUID mBootScriptThunkGuid = {
28 0xa053f561, 0xf56b, 0x4140, {0x89, 0x1, 0xb4, 0xcb, 0x5d, 0x70, 0x92, 0x9e}
29 };
30
31 /**
32 Entry point function of the Boot Script Thunk Helper SMM driver.
33
34 @param[in] ImageHandle The firmware allocated handle for the EFI image.
35 @param[in] SystemTable A pointer to the EFI System Table.
36
37 @retval EFI_SUCCESS The entry point is executed successfully.
38 @retval other Some error occurs when executing this entry point.
39 **/
40 EFI_STATUS
41 EFIAPI
BootScriptThunkHelperMain(IN EFI_HANDLE ImageHandle,IN EFI_SYSTEM_TABLE * SystemTable)42 BootScriptThunkHelperMain (
43 IN EFI_HANDLE ImageHandle,
44 IN EFI_SYSTEM_TABLE *SystemTable
45 )
46 {
47 BOOT_SCRIPT_THUNK_DATA *BootScriptThunkData;
48 EFI_STATUS Status;
49
50 //
51 // Get BootScriptThunk variable
52 //
53 BootScriptThunkData = (BOOT_SCRIPT_THUNK_DATA *)(UINTN)PcdGet64(BootScriptThunkDataPtr);
54 ASSERT (BootScriptThunkData != NULL);
55 if (BootScriptThunkData == NULL) {
56 return EFI_NOT_FOUND;
57 }
58
59 //
60 // Save BootScriptThunk image
61 //
62 Status = SaveLockBox (
63 &mBootScriptThunkGuid,
64 (VOID *)(UINTN)BootScriptThunkData->BootScriptThunkBase,
65 (UINTN)BootScriptThunkData->BootScriptThunkLength
66 );
67 ASSERT_EFI_ERROR (Status);
68
69 Status = SetLockBoxAttributes (&mBootScriptThunkGuid, LOCK_BOX_ATTRIBUTE_RESTORE_IN_PLACE);
70 ASSERT_EFI_ERROR (Status);
71
72 return Status;
73 }
74