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
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
|
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Unlike log.c this implements TPM log according to TPM2.0 specification
* rather then using coreboot-specific log format.
*
* First entry is in TPM1.2 format and serves as a header, the rest are in
* a newer (agile) format which supports SHA256 and multiple hashes, but we
* store only one hash.
*
* This is defined in "TCG EFI Protocol Specification".
*/
#include <endian.h>
#include <console/console.h>
#include <security/tpm/tspi.h>
#include <security/tpm/tspi/crtm.h>
#include <security/tpm/tspi/logs.h>
#include <region_file.h>
#include <string.h>
#include <symbols.h>
#include <cbmem.h>
#include <vb2_sha.h>
static uint16_t tpmalg_from_vb2_hash(enum vb2_hash_algorithm hash_type)
{
switch (hash_type) {
case VB2_HASH_SHA1:
return TPM2_ALG_SHA1;
case VB2_HASH_SHA256:
return TPM2_ALG_SHA256;
case VB2_HASH_SHA384:
return TPM2_ALG_SHA384;
case VB2_HASH_SHA512:
return TPM2_ALG_SHA512;
default:
return 0xFF;
}
}
void *tpm2_log_cbmem_init(void)
{
static struct tpm_2_log_table *tclt;
if (tclt)
return tclt;
if (ENV_HAS_CBMEM) {
size_t tpm_log_len;
struct tcg_efi_spec_id_event *hdr;
tclt = cbmem_find(CBMEM_ID_TPM2_TCG_LOG);
if (tclt)
return tclt;
tpm_log_len = sizeof(struct tpm_2_log_table) +
MAX_TPM_LOG_ENTRIES * sizeof(struct tpm_2_log_entry);
tclt = cbmem_add(CBMEM_ID_TPM2_TCG_LOG, tpm_log_len);
if (!tclt)
return NULL;
memset(tclt, 0, tpm_log_len);
hdr = &tclt->header;
hdr->event_type = htole32(EV_NO_ACTION);
hdr->event_size = htole32(33 + sizeof(tclt->vendor));
strcpy((char *)hdr->signature, TPM_20_SPEC_ID_EVENT_SIGNATURE);
hdr->platform_class = htole32(0x00); // client platform
hdr->spec_version_minor = 0x00;
hdr->spec_version_major = 0x02;
hdr->spec_errata = 0x00;
hdr->uintn_size = 0x02; // 64-bit UINT
hdr->num_of_algorithms = htole32(1);
hdr->digest_sizes[0].alg_id = htole16(tpmalg_from_vb2_hash(TPM_MEASURE_ALGO));
hdr->digest_sizes[0].digest_size = htole16(vb2_digest_size(TPM_MEASURE_ALGO));
tclt->vendor_info_size = sizeof(tclt->vendor);
tclt->vendor.reserved = 0;
tclt->vendor.version_major = TPM_20_LOG_VI_MAJOR;
tclt->vendor.version_minor = TPM_20_LOG_VI_MINOR;
tclt->vendor.magic = htole32(TPM_20_LOG_VI_MAGIC);
tclt->vendor.max_entries = htole16(MAX_TPM_LOG_ENTRIES);
tclt->vendor.num_entries = htole16(0);
tclt->vendor.entry_size = htole32(sizeof(struct tpm_2_log_entry));
}
return tclt;
}
void tpm2_log_dump(void)
{
int i, j;
struct tpm_2_log_table *tclt;
int hash_size;
const char *alg_name;
tclt = tpm_log_init();
if (!tclt)
return;
hash_size = vb2_digest_size(TPM_MEASURE_ALGO);
alg_name = vb2_get_hash_algorithm_name(TPM_MEASURE_ALGO);
printk(BIOS_INFO, "coreboot TPM 2.0 measurements:\n\n");
for (i = 0; i < le16toh(tclt->vendor.num_entries); i++) {
struct tpm_2_log_entry *tce = &tclt->entries[i];
printk(BIOS_INFO, " PCR-%u ", le32toh(tce->pcr));
for (j = 0; j < hash_size; j++)
printk(BIOS_INFO, "%02x", tce->digest[j]);
printk(BIOS_INFO, " %s [%s]\n", alg_name, tce->data);
}
printk(BIOS_INFO, "\n");
}
void tpm2_log_add_table_entry(const char *name, const uint32_t pcr,
enum vb2_hash_algorithm digest_algo,
const uint8_t *digest,
const size_t digest_len)
{
struct tpm_2_log_table *tclt;
struct tpm_2_log_entry *tce;
tclt = tpm_log_init();
if (!tclt) {
printk(BIOS_WARNING, "TPM LOG: non-existent!\n");
return;
}
if (!name) {
printk(BIOS_WARNING, "TPM LOG: entry name not set\n");
return;
}
if (digest_algo != TPM_MEASURE_ALGO) {
printk(BIOS_WARNING, "TPM LOG: digest is of unsupported type: %s\n",
vb2_get_hash_algorithm_name(digest_algo));
return;
}
if (digest_len != vb2_digest_size(TPM_MEASURE_ALGO)) {
printk(BIOS_WARNING, "TPM LOG: digest has invalid length: %d\n",
(int)digest_len);
return;
}
if (le16toh(tclt->vendor.num_entries) >= le16toh(tclt->vendor.max_entries)) {
printk(BIOS_WARNING, "TPM LOG: log table is full\n");
return;
}
tce = &tclt->entries[le16toh(tclt->vendor.num_entries)];
tclt->vendor.num_entries = htole16(le16toh(tclt->vendor.num_entries) + 1);
tce->pcr = htole32(pcr);
tce->event_type = htole32(EV_ACTION);
tce->digest_count = htole32(1);
tce->digest_type = htole16(tpmalg_from_vb2_hash(TPM_MEASURE_ALGO));
memcpy(tce->digest, digest, vb2_digest_size(TPM_MEASURE_ALGO));
tce->data_length = htole32(sizeof(tce->data));
strncpy((char *)tce->data, name, sizeof(tce->data) - 1);
tce->data[sizeof(tce->data) - 1] = '\0';
}
int tpm2_log_get(int entry_idx, int *pcr, const uint8_t **digest_data,
enum vb2_hash_algorithm *digest_algo, const char **event_name)
{
struct tpm_2_log_table *tclt;
struct tpm_2_log_entry *tce;
tclt = tpm_log_init();
if (!tclt)
return 1;
if (entry_idx < 0 || entry_idx >= le16toh(tclt->vendor.num_entries))
return 1;
tce = &tclt->entries[entry_idx];
*pcr = le32toh(tce->pcr);
*digest_data = tce->digest;
*digest_algo = TPM_MEASURE_ALGO; /* We validate algorithm on addition */
*event_name = (char *)tce->data;
return 0;
}
uint16_t tpm2_log_get_size(const void *log_table)
{
const struct tpm_2_log_table *tclt = log_table;
return le16toh(tclt->vendor.num_entries);
}
void tpm2_preram_log_clear(void)
{
printk(BIOS_INFO, "TPM LOG: clearing the log\n");
/*
* Pre-RAM log is only for internal use and isn't exported anywhere, hence it's header
* is not initialized.
*/
struct tpm_2_log_table *tclt = (struct tpm_2_log_table *)_tpm_log;
tclt->vendor.max_entries = htole16(MAX_TPM_LOG_ENTRIES);
tclt->vendor.num_entries = htole16(0);
}
void tpm2_log_copy_entries(const void *from, void *to)
{
const struct tpm_2_log_table *from_log = from;
struct tpm_2_log_table *to_log = to;
int i;
for (i = 0; i < le16toh(from_log->vendor.num_entries); i++) {
if (le16toh(to_log->vendor.num_entries) >= le16toh(to_log->vendor.max_entries)) {
printk(BIOS_WARNING, "TPM LOG: log table is full\n");
return;
}
struct tpm_2_log_entry *tce =
&to_log->entries[le16toh(to_log->vendor.num_entries)];
to_log->vendor.num_entries = htole16(le16toh(to_log->vendor.num_entries) + 1);
tce->pcr = from_log->entries[i].pcr;
tce->event_type = from_log->entries[i].event_type;
tce->digest_count = from_log->entries[i].digest_count;
tce->digest_type = from_log->entries[i].digest_type;
memcpy(tce->digest, from_log->entries[i].digest, sizeof(tce->digest));
tce->data_length = from_log->entries[i].data_length;
memcpy(tce->data, from_log->entries[i].data, sizeof(tce->data));
}
}
|
