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
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
|
/*
* This file is part of the coreboot project.
*
* Copyright (C) 2016 Intel Corp.
* Copyright (C) 2017-2019 Eltan B.V.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <boot_device.h>
#include <cbfs.h>
#include <vboot_check.h>
#include <vboot_common.h>
#define RSA_PUBLICKEY_FILE_NAME "vboot_public_key.bin"
#if CONFIG(VENDORCODE_ELTAN_VBOOT_USE_SHA512)
#define DIGEST_SIZE VB2_SHA512_DIGEST_SIZE
#define HASH_ALG VB2_HASH_SHA512
#else
#define DIGEST_SIZE VB2_SHA256_DIGEST_SIZE
#define HASH_ALG VB2_HASH_SHA256
#endif
int verified_boot_check_manifest(void)
{
uint8_t *buffer;
uint8_t sig_buffer[1024]; /* used to build vb21_signature */
size_t size = 0;
struct vb2_public_key key;
struct vb2_workbuf wb;
struct vb21_signature *vb2_sig_hdr = (struct vb21_signature *)sig_buffer;
uint8_t wb_buffer[1024];
buffer = cbfs_boot_map_with_leak(RSA_PUBLICKEY_FILE_NAME, CBFS_TYPE_RAW, &size);
if (!buffer || !size) {
printk(BIOS_ERR, "ERROR: Public key not found!\n");
goto fail;
}
if ((size != CONFIG_VENDORCODE_ELTAN_VBOOT_KEY_SIZE) ||
(buffer != (void *)CONFIG_VENDORCODE_ELTAN_VBOOT_KEY_LOCATION)) {
printk(BIOS_ERR, "ERROR: Illegal public key!\n");
goto fail;
}
if (vb21_unpack_key(&key, buffer, size)) {
printk(BIOS_ERR, "ERROR: Invalid public key!\n");
goto fail;
}
cbfs_boot_map_with_leak("oemmanifest.bin", CBFS_TYPE_RAW, &size);
if (size != (CONFIG_VENDORCODE_ELTAN_OEM_MANIFEST_ITEMS * DIGEST_SIZE) +
vb2_rsa_sig_size(VB2_SIG_RSA2048)) {
printk(BIOS_ERR, "ERROR: Incorrect manifest size!\n");
goto fail;
}
/* prepare work buffer structure */
wb.buf = (uint8_t *)&wb_buffer;
wb.size = sizeof(wb_buffer);
/* Build vb2_sig_hdr buffer */
vb2_sig_hdr->sig_offset = sizeof(struct vb21_signature) +
(CONFIG_VENDORCODE_ELTAN_OEM_MANIFEST_ITEMS * DIGEST_SIZE);
vb2_sig_hdr->sig_alg = VB2_SIG_RSA2048;
vb2_sig_hdr->sig_size = vb2_rsa_sig_size(VB2_SIG_RSA2048);
vb2_sig_hdr->hash_alg = HASH_ALG;
vb2_sig_hdr->data_size = CONFIG_VENDORCODE_ELTAN_OEM_MANIFEST_ITEMS * DIGEST_SIZE;
memcpy(&sig_buffer[sizeof(struct vb21_signature)],
(uint8_t *)CONFIG_VENDORCODE_ELTAN_OEM_MANIFEST_LOC, size);
if (vb21_verify_data(&sig_buffer[sizeof(struct vb21_signature)], vb2_sig_hdr->data_size,
(struct vb21_signature *)&sig_buffer, &key, &wb)) {
printk(BIOS_ERR, "ERROR: Signature verification failed for hash table\n");
goto fail;
}
printk(BIOS_INFO, "%s: Successfully verified hash_table signature.\n", __func__);
return 0;
fail:
die("HASH table verification failed!\n");
return -1;
}
/*
*
* measure_item
*
* extends the defined pcr using the hash calculated by the verified boot
* routines.
*
* @param[in] pcr PCR to extend
* @param[in] *hashData Pointer to the hash data
* @param[in] hashDataLen Length of the hash data
* @param[in] *event_msg Message to log or display
* @param[in] eventType Event type to use when logging
* @retval TPM_SUCCESS Operation completed successfully.
* @retval TPM_E_IOERROR Unexpected device behavior.
*/
static int measure_item(uint32_t pcr, uint8_t *hashData, uint32_t hashDataLen,
int8_t *event_msg, TCG_EVENTTYPE eventType)
{
int status = TPM_SUCCESS;
TCG_PCR_EVENT2_HDR tcgEventHdr;
memset(&tcgEventHdr, 0, sizeof(tcgEventHdr));
tcgEventHdr.pcrIndex = pcr;
tcgEventHdr.eventType = eventType;
if (event_msg) {
status = mboot_hash_extend_log(MBOOT_HASH_PROVIDED, hashData,
hashDataLen, &tcgEventHdr,
(uint8_t *)event_msg);
if (status == TPM_SUCCESS)
printk(BIOS_INFO, "%s: Success! %s measured to pcr %d.\n", __func__,
event_msg, pcr);
}
return status;
}
static void verified_boot_check_buffer(const char *name, void *start, size_t size,
uint32_t hash_index, int32_t pcr)
{
uint8_t digest[DIGEST_SIZE];
int hash_algorithm;
vb2_error_t status;
printk(BIOS_DEBUG, "%s: %s HASH verification buffer %p size %d\n", __func__, name,
start, (int)size);
if (start && size) {
if (CONFIG(VENDORCODE_ELTAN_VBOOT_USE_SHA512))
hash_algorithm = VB2_HASH_SHA512;
else
hash_algorithm = VB2_HASH_SHA256;
status = cb_sha_little_endian(hash_algorithm, (const uint8_t *)start, size,
digest);
if ((CONFIG(VENDORCODE_ELTAN_VBOOT) && memcmp((void *)(
(uint8_t *)CONFIG_VENDORCODE_ELTAN_OEM_MANIFEST_LOC +
sizeof(digest) * hash_index), digest, sizeof(digest))) || status) {
printk(BIOS_DEBUG, "%s: buffer hash\n", __func__);
hexdump(digest, sizeof(digest));
printk(BIOS_DEBUG, "%s: manifest hash\n", __func__);
hexdump((void *)( (uint8_t *)CONFIG_VENDORCODE_ELTAN_OEM_MANIFEST_LOC +
sizeof(digest) * hash_index), sizeof(digest));
printk(BIOS_EMERG, "%s ", name);
die("HASH verification failed!\n");
} else {
if (!ENV_BOOTBLOCK && CONFIG(VENDORCODE_ELTAN_MBOOT)) {
if (pcr != -1) {
printk(BIOS_DEBUG, "%s: measuring %s\n", __func__,
name);
if (measure_item(pcr, digest, sizeof(digest),
(int8_t *)name, 0))
printk(BIOS_DEBUG, "%s: measuring failed!\n",
__func__);
}
}
if (CONFIG(VENDORCODE_ELTAN_VBOOT))
printk(BIOS_DEBUG, "%s HASH verification success\n", name);
}
} else {
printk(BIOS_EMERG, "Invalid buffer\n");
die("HASH verification failed!\n");
}
}
void verified_boot_check_cbfsfile(const char *name, uint32_t type, uint32_t hash_index,
void **buffer, uint32_t *filesize, int32_t pcr)
{
void *start;
size_t size;
start = cbfs_boot_map_with_leak(name, type & ~VERIFIED_BOOT_COPY_BLOCK, &size);
if (start && size) {
/* Speed up processing by copying the file content to memory first */
if (!ENV_ROMSTAGE_OR_BEFORE && (type & VERIFIED_BOOT_COPY_BLOCK) && (buffer) &&
(*buffer) && ((uint32_t) start > (uint32_t)(~(CONFIG_CBFS_SIZE-1)))) {
printk(BIOS_DEBUG, "%s: move buffer to memory\n", __func__);
/* Move the file to a memory bufferof which we know it doesn't harm */
memcpy(*buffer, start, size);
start = *buffer;
printk(BIOS_DEBUG, "%s: done\n", __func__);
}
verified_boot_check_buffer(name, start, size, hash_index, pcr);
} else {
printk(BIOS_EMERG, "CBFS Failed to get file content for %s\n", name);
die("HASH verification failed!\n");
}
if (buffer)
*buffer = start;
if (filesize)
*filesize = size;
}
void process_verify_list(const verify_item_t list[])
{
int i = 0;
while (list[i].type != VERIFY_TERMINATOR) {
switch (list[i].type) {
case VERIFY_FILE:
verified_boot_check_cbfsfile(list[i].name, list[i].data.file.cbfs_type,
list[i].hash_index, NULL, NULL, list[i].pcr);
if (list[i].data.file.related_items) {
printk(BIOS_SPEW, "process related items\n");
process_verify_list(
(verify_item_t *)list[i].data.file.related_items);
}
break;
case VERIFY_BLOCK:
verified_boot_check_buffer(list[i].name,
(void *)list[i].data.block.start,
list[i].data.block.size,
list[i].hash_index, list[i].pcr);
break;
default:
printk(BIOS_EMERG, "INVALID TYPE IN VERIFY LIST 0x%x\n", list[i].type);
die("HASH verification failed!\n");
}
i++;
}
}
/*
* BOOTBLOCK
*/
void verified_boot_bootblock_check(void)
{
printk(BIOS_SPEW, "%s: processing bootblock items\n", __func__);
if (CONFIG(VENDORCODE_ELTAN_VBOOT_SIGNED_MANIFEST)) {
printk(BIOS_SPEW, "%s: check the manifest\n", __func__);
if (verified_boot_check_manifest() != 0)
die("invalid manifest");
}
printk(BIOS_SPEW, "%s: process bootblock verify list\n", __func__);
process_verify_list(bootblock_verify_list);
}
/*
* ROMSTAGE
*/
void verified_boot_early_check(void)
{
printk(BIOS_SPEW, "%s: processing early items\n", __func__);
if (!CONFIG(C_ENVIRONMENT_BOOTBLOCK) &&
CONFIG(VENDORCODE_ELTAN_VBOOT_SIGNED_MANIFEST)) {
printk(BIOS_SPEW, "%s: check the manifest\n", __func__);
if (verified_boot_check_manifest() != 0)
die("invalid manifest");
}
if (CONFIG(VENDORCODE_ELTAN_MBOOT)) {
printk(BIOS_DEBUG, "mb_measure returned 0x%x\n",
mb_measure(vboot_platform_is_resuming()));
}
printk(BIOS_SPEW, "%s: process early verify list\n", __func__);
process_verify_list(romstage_verify_list);
}
/*
* RAM STAGE
*/
static int process_oprom_list(const verify_item_t list[],
struct rom_header *rom_header)
{
int i = 0;
struct pci_data *rom_data;
uint32_t viddevid = 0;
if (le32_to_cpu(rom_header->signature) != PCI_ROM_HDR) {
printk(BIOS_ERR, "Incorrect expansion ROM header signature %04x DONT START\n",
le32_to_cpu(rom_header->signature));
return 0;
}
rom_data = (((void *)rom_header) + le32_to_cpu(rom_header->data));
viddevid |= (rom_data->vendor << 16);
viddevid |= rom_data->device;
while (list[i].type != VERIFY_TERMINATOR) {
switch (list[i].type) {
case VERIFY_OPROM:
if (viddevid == list[i].data.oprom.viddev) {
verified_boot_check_buffer(list[i].name,
(void *)rom_header,
rom_header->size * 512,
list[i].hash_index, list[i].pcr);
if (list[i].data.oprom.related_items) {
printk(BIOS_SPEW, "%s: process related items\n",
__func__);
process_verify_list(
(verify_item_t *)list[i].data.oprom.related_items);
}
printk(BIOS_SPEW, "%s: option rom can be started\n", __func__);
return 1;
}
break;
default:
printk(BIOS_EMERG, "%s: INVALID TYPE IN OPTION ROM LIST 0x%x\n",
__func__, list[i].type);
die("HASH verification failed!\n");
}
i++;
}
printk(BIOS_ERR, "%s: option rom not in list DONT START\n", __func__);
return 0;
}
int verified_boot_should_run_oprom(struct rom_header *rom_header)
{
return process_oprom_list(oprom_verify_list, rom_header);
}
int prog_locate_hook(struct prog *prog)
{
if (ENV_BOOTBLOCK) {
printk(BIOS_SPEW, "%s: bootblock\n", __func__);
verified_boot_bootblock_check();
}
if (ENV_ROMSTAGE) {
static int prepare_romstage = 0;
printk(BIOS_SPEW, "%s: romstage\n", __func__);
if (!prepare_romstage) {
verified_boot_early_check();
prepare_romstage = 1;
}
}
if (ENV_POSTCAR) {
printk(BIOS_SPEW, "%s: postcar\n", __func__);
process_verify_list(postcar_verify_list);
}
if (ENV_RAMSTAGE) {
printk(BIOS_SPEW, "%s: ramstage\n", __func__);
process_verify_list(payload_verify_list);
}
return 0;
}
|