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
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2005 IBM Corporation
*
* Authors:
* Seiji Munetoh <munetoh@jp.ibm.com>
* Stefan Berger <stefanb@us.ibm.com>
* Reiner Sailer <sailer@watson.ibm.com>
* Kylene Hall <kjhall@us.ibm.com>
* Nayna Jain <nayna@linux.vnet.ibm.com>
*
* Maintained by: <tpmdd-devel@lists.sourceforge.net>
*
* Access to the event log extended by the TCG BIOS of PC platform
*/
#include <linux/seq_file.h>
#include <linux/fs.h>
#include <linux/security.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/acpi.h>
#include <linux/tpm_eventlog.h>
#include "../tpm.h"
#include "common.h"
struct acpi_tcpa {
struct acpi_table_header hdr;
u16 platform_class;
union {
struct client_hdr {
u32 log_max_len __packed;
u64 log_start_addr __packed;
} client;
struct server_hdr {
u16 reserved;
u64 log_max_len __packed;
u64 log_start_addr __packed;
} server;
};
};
/* Check that the given log is indeed a TPM2 log. */
static bool tpm_is_tpm2_log(void *bios_event_log, u64 len)
{
struct tcg_efi_specid_event_head *efispecid;
struct tcg_pcr_event *event_header;
int n;
if (len < sizeof(*event_header))
return false;
len -= sizeof(*event_header);
event_header = bios_event_log;
if (len < sizeof(*efispecid))
return false;
efispecid = (struct tcg_efi_specid_event_head *)event_header->event;
n = memcmp(efispecid->signature, TCG_SPECID_SIG,
sizeof(TCG_SPECID_SIG));
return n == 0;
}
/* read binary bios log */
int tpm_read_log_acpi(struct tpm_chip *chip)
{
struct acpi_tcpa *buff;
acpi_status status;
void __iomem *virt;
u64 len, start;
struct tpm_bios_log *log;
struct acpi_table_tpm2 *tbl;
struct acpi_tpm2_phy *tpm2_phy;
int format;
int ret;
log = &chip->log;
/* Unfortuntely ACPI does not associate the event log with a specific
* TPM, like PPI. Thus all ACPI TPMs will read the same log.
*/
if (!chip->acpi_dev_handle)
return -ENODEV;
if (chip->flags & TPM_CHIP_FLAG_TPM2) {
status = acpi_get_table("TPM2", 1,
(struct acpi_table_header **)&tbl);
if (ACPI_FAILURE(status))
return -ENODEV;
if (tbl->header.length <
sizeof(*tbl) + sizeof(struct acpi_tpm2_phy))
return -ENODEV;
tpm2_phy = (void *)tbl + sizeof(*tbl);
len = tpm2_phy->log_area_minimum_length;
start = tpm2_phy->log_area_start_address;
if (!start || !len)
return -ENODEV;
format = EFI_TCG2_EVENT_LOG_FORMAT_TCG_2;
} else {
/* Find TCPA entry in RSDT (ACPI_LOGICAL_ADDRESSING) */
status = acpi_get_table(ACPI_SIG_TCPA, 1,
(struct acpi_table_header **)&buff);
if (ACPI_FAILURE(status))
return -ENODEV;
switch (buff->platform_class) {
case BIOS_SERVER:
len = buff->server.log_max_len;
start = buff->server.log_start_addr;
break;
case BIOS_CLIENT:
default:
len = buff->client.log_max_len;
start = buff->client.log_start_addr;
break;
}
format = EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2;
}
if (!len) {
dev_warn(&chip->dev, "%s: TCPA log area empty\n", __func__);
return -EIO;
}
/* malloc EventLog space */
log->bios_event_log = kmalloc(len, GFP_KERNEL);
if (!log->bios_event_log)
return -ENOMEM;
log->bios_event_log_end = log->bios_event_log + len;
ret = -EIO;
virt = acpi_os_map_iomem(start, len);
if (!virt)
goto err;
memcpy_fromio(log->bios_event_log, virt, len);
acpi_os_unmap_iomem(virt, len);
if (chip->flags & TPM_CHIP_FLAG_TPM2 &&
!tpm_is_tpm2_log(log->bios_event_log, len)) {
/* try EFI log next */
ret = -ENODEV;
goto err;
}
return format;
err:
kfree(log->bios_event_log);
log->bios_event_log = NULL;
return ret;
}
|
