1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
|
/*
* EFI Boot Guard
*
* Copyright (c) Siemens AG, 2020
*
* Authors:
* Dr. Johann Pfefferl <johann.pfefferl@siemens.com>
* Jan Kiszka <jan.kiszka@siemens.com>
* Cedric Hombourger <cedric.hombourger@siemens.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
* SPDX-License-Identifier: GPL-2.0-only
*/
#include <efi.h>
#include <efilib.h>
#include "simatic.h"
#include "smbios.h"
#include "utils.h"
static UINT32 station_id;
static BOOLEAN station_id_cached;
static UINT32 get_station_id(SMBIOS_STRUCTURE_POINTER oem_strct)
{
SIMATIC_OEM_ENTRY *entry;
UINTN n;
entry = (SIMATIC_OEM_ENTRY *)(oem_strct.Raw + sizeof(*oem_strct.Hdr));
/* Find 4th entry in OEM data. */
for (n = 0; n < 3; n++) {
if (entry->type != SIMATIC_OEM_ENTRY_TYPE_BINARY) {
return 0;
}
entry = (SIMATIC_OEM_ENTRY *)((UINT8 *)entry + entry->length);
}
if (entry->type == SIMATIC_OEM_ENTRY_TYPE_BINARY &&
entry->length == sizeof(SIMATIC_OEM_ENTRY)) {
return entry->station_id;
}
return 0;
}
UINT32 simatic_station_id(VOID)
{
if (station_id_cached)
return station_id;
SMBIOS_STRUCTURE_TABLE *smbios_table;
SMBIOS_STRUCTURE_POINTER smbios_struct;
EFI_STATUS status;
status = LibGetSystemConfigurationTable(&SMBIOSTableGuid,
(VOID **)&smbios_table);
if (status != EFI_SUCCESS) {
return 0;
}
smbios_struct = smbios_find_struct(smbios_table, SMBIOS_TYPE_OEM_129);
if (smbios_struct.Raw == NULL) {
return 0;
}
station_id = get_station_id(smbios_struct);
station_id_cached = TRUE;
return station_id;
}
|
