1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2004 IBM Corporation
4 * Authors:
5 * Leendert van Doorn <leendert@watson.ibm.com>
6 * Dave Safford <safford@watson.ibm.com>
7 * Reiner Sailer <sailer@watson.ibm.com>
8 * Kylene Hall <kjhall@us.ibm.com>
9 *
10 * Copyright (C) 2013 Obsidian Research Corp
11 * Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
12 *
13 * sysfs filesystem inspection interface to the TPM
14 */
15 #include <linux/device.h>
16 #include "tpm.h"
17
18 struct tpm_readpubek_out {
19 u8 algorithm[4];
20 u8 encscheme[2];
21 u8 sigscheme[2];
22 __be32 paramsize;
23 u8 parameters[12];
24 __be32 keysize;
25 u8 modulus[256];
26 u8 checksum[20];
27 } __packed;
28
29 #define READ_PUBEK_RESULT_MIN_BODY_SIZE (28 + 256)
30 #define TPM_ORD_READPUBEK 124
31
pubek_show(struct device * dev,struct device_attribute * attr,char * buf)32 static ssize_t pubek_show(struct device *dev, struct device_attribute *attr,
33 char *buf)
34 {
35 struct tpm_readpubek_out *out;
36 int i;
37 char *str = buf;
38 struct tpm_chip *chip = to_tpm_chip(dev);
39 char anti_replay[20];
40 struct tpm_buf *tpm_buf __free(kfree) = NULL;
41
42 memset(&anti_replay, 0, sizeof(anti_replay));
43
44 if (tpm_try_get_ops(chip))
45 return 0;
46
47 tpm_buf = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
48 if (!tpm_buf) {
49 tpm_put_ops(chip);
50 return 0;
51 }
52
53 tpm_buf_init(tpm_buf, TPM_BUFSIZE);
54 tpm_buf_reset(tpm_buf, TPM_TAG_RQU_COMMAND, TPM_ORD_READPUBEK);
55 tpm_buf_append(tpm_buf, anti_replay, sizeof(anti_replay));
56
57 if (tpm_transmit_cmd(chip, tpm_buf, READ_PUBEK_RESULT_MIN_BODY_SIZE,
58 "attempting to read the PUBEK")) {
59 tpm_put_ops(chip);
60 return 0;
61 }
62
63 out = (struct tpm_readpubek_out *)&tpm_buf->data[10];
64 str +=
65 sprintf(str,
66 "Algorithm: %4ph\n"
67 "Encscheme: %2ph\n"
68 "Sigscheme: %2ph\n"
69 "Parameters: %12ph\n"
70 "Modulus length: %d\n"
71 "Modulus:\n",
72 out->algorithm,
73 out->encscheme,
74 out->sigscheme,
75 out->parameters,
76 be32_to_cpu(out->keysize));
77
78 for (i = 0; i < 256; i += 16)
79 str += sprintf(str, "%16ph\n", &out->modulus[i]);
80
81 tpm_put_ops(chip);
82 return str - buf;
83 }
84 static DEVICE_ATTR_RO(pubek);
85
pcrs_show(struct device * dev,struct device_attribute * attr,char * buf)86 static ssize_t pcrs_show(struct device *dev, struct device_attribute *attr,
87 char *buf)
88 {
89 cap_t cap;
90 u8 digest[TPM_DIGEST_SIZE];
91 u32 i, j, num_pcrs;
92 char *str = buf;
93 struct tpm_chip *chip = to_tpm_chip(dev);
94
95 if (tpm_try_get_ops(chip))
96 return 0;
97
98 if (tpm1_getcap(chip, TPM_CAP_PROP_PCR, &cap,
99 "attempting to determine the number of PCRS",
100 sizeof(cap.num_pcrs))) {
101 tpm_put_ops(chip);
102 return 0;
103 }
104
105 num_pcrs = be32_to_cpu(cap.num_pcrs);
106 for (i = 0; i < num_pcrs; i++) {
107 if (tpm1_pcr_read(chip, i, digest)) {
108 str = buf;
109 break;
110 }
111 str += sprintf(str, "PCR-%02d: ", i);
112 for (j = 0; j < TPM_DIGEST_SIZE; j++)
113 str += sprintf(str, "%02X ", digest[j]);
114 str += sprintf(str, "\n");
115 }
116 tpm_put_ops(chip);
117 return str - buf;
118 }
119 static DEVICE_ATTR_RO(pcrs);
120
enabled_show(struct device * dev,struct device_attribute * attr,char * buf)121 static ssize_t enabled_show(struct device *dev, struct device_attribute *attr,
122 char *buf)
123 {
124 struct tpm_chip *chip = to_tpm_chip(dev);
125 ssize_t rc = 0;
126 cap_t cap;
127
128 if (tpm_try_get_ops(chip))
129 return 0;
130
131 if (tpm1_getcap(chip, TPM_CAP_FLAG_PERM, &cap,
132 "attempting to determine the permanent enabled state",
133 sizeof(cap.perm_flags)))
134 goto out_ops;
135
136 rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
137 out_ops:
138 tpm_put_ops(chip);
139 return rc;
140 }
141 static DEVICE_ATTR_RO(enabled);
142
active_show(struct device * dev,struct device_attribute * attr,char * buf)143 static ssize_t active_show(struct device *dev, struct device_attribute *attr,
144 char *buf)
145 {
146 struct tpm_chip *chip = to_tpm_chip(dev);
147 ssize_t rc = 0;
148 cap_t cap;
149
150 if (tpm_try_get_ops(chip))
151 return 0;
152
153 if (tpm1_getcap(chip, TPM_CAP_FLAG_PERM, &cap,
154 "attempting to determine the permanent active state",
155 sizeof(cap.perm_flags)))
156 goto out_ops;
157
158 rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
159 out_ops:
160 tpm_put_ops(chip);
161 return rc;
162 }
163 static DEVICE_ATTR_RO(active);
164
owned_show(struct device * dev,struct device_attribute * attr,char * buf)165 static ssize_t owned_show(struct device *dev, struct device_attribute *attr,
166 char *buf)
167 {
168 struct tpm_chip *chip = to_tpm_chip(dev);
169 ssize_t rc = 0;
170 cap_t cap;
171
172 if (tpm_try_get_ops(chip))
173 return 0;
174
175 if (tpm1_getcap(to_tpm_chip(dev), TPM_CAP_PROP_OWNER, &cap,
176 "attempting to determine the owner state",
177 sizeof(cap.owned)))
178 goto out_ops;
179
180 rc = sprintf(buf, "%d\n", cap.owned);
181 out_ops:
182 tpm_put_ops(chip);
183 return rc;
184 }
185 static DEVICE_ATTR_RO(owned);
186
temp_deactivated_show(struct device * dev,struct device_attribute * attr,char * buf)187 static ssize_t temp_deactivated_show(struct device *dev,
188 struct device_attribute *attr, char *buf)
189 {
190 struct tpm_chip *chip = to_tpm_chip(dev);
191 ssize_t rc = 0;
192 cap_t cap;
193
194 if (tpm_try_get_ops(chip))
195 return 0;
196
197 if (tpm1_getcap(to_tpm_chip(dev), TPM_CAP_FLAG_VOL, &cap,
198 "attempting to determine the temporary state",
199 sizeof(cap.stclear_flags)))
200 goto out_ops;
201
202 rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
203 out_ops:
204 tpm_put_ops(chip);
205 return rc;
206 }
207 static DEVICE_ATTR_RO(temp_deactivated);
208
caps_show(struct device * dev,struct device_attribute * attr,char * buf)209 static ssize_t caps_show(struct device *dev, struct device_attribute *attr,
210 char *buf)
211 {
212 struct tpm_chip *chip = to_tpm_chip(dev);
213 struct tpm1_version *version;
214 ssize_t rc = 0;
215 char *str = buf;
216 cap_t cap;
217
218 if (tpm_try_get_ops(chip))
219 return 0;
220
221 if (tpm1_getcap(chip, TPM_CAP_PROP_MANUFACTURER, &cap,
222 "attempting to determine the manufacturer",
223 sizeof(cap.manufacturer_id)))
224 goto out_ops;
225
226 str += sprintf(str, "Manufacturer: 0x%x\n",
227 be32_to_cpu(cap.manufacturer_id));
228
229 /* TPM 1.2 */
230 if (!tpm1_getcap(chip, TPM_CAP_VERSION_1_2, &cap,
231 "attempting to determine the 1.2 version",
232 sizeof(cap.version2))) {
233 version = &cap.version2.version;
234 goto out_print;
235 }
236
237 /* TPM 1.1 */
238 if (tpm1_getcap(chip, TPM_CAP_VERSION_1_1, &cap,
239 "attempting to determine the 1.1 version",
240 sizeof(cap.version1))) {
241 goto out_ops;
242 }
243
244 version = &cap.version1;
245
246 out_print:
247 str += sprintf(str,
248 "TCG version: %d.%d\nFirmware version: %d.%d\n",
249 version->major, version->minor,
250 version->rev_major, version->rev_minor);
251
252 rc = str - buf;
253
254 out_ops:
255 tpm_put_ops(chip);
256 return rc;
257 }
258 static DEVICE_ATTR_RO(caps);
259
cancel_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)260 static ssize_t cancel_store(struct device *dev, struct device_attribute *attr,
261 const char *buf, size_t count)
262 {
263 struct tpm_chip *chip = to_tpm_chip(dev);
264
265 if (tpm_try_get_ops(chip))
266 return 0;
267
268 chip->ops->cancel(chip);
269 tpm_put_ops(chip);
270 return count;
271 }
272 static DEVICE_ATTR_WO(cancel);
273
durations_show(struct device * dev,struct device_attribute * attr,char * buf)274 static ssize_t durations_show(struct device *dev, struct device_attribute *attr,
275 char *buf)
276 {
277 struct tpm_chip *chip = to_tpm_chip(dev);
278
279 if (chip->duration[TPM_LONG] == 0)
280 return 0;
281
282 return sprintf(buf, "%d %d %d [%s]\n",
283 jiffies_to_usecs(chip->duration[TPM_SHORT]),
284 jiffies_to_usecs(chip->duration[TPM_MEDIUM]),
285 jiffies_to_usecs(chip->duration[TPM_LONG]),
286 chip->duration_adjusted
287 ? "adjusted" : "original");
288 }
289 static DEVICE_ATTR_RO(durations);
290
timeouts_show(struct device * dev,struct device_attribute * attr,char * buf)291 static ssize_t timeouts_show(struct device *dev, struct device_attribute *attr,
292 char *buf)
293 {
294 struct tpm_chip *chip = to_tpm_chip(dev);
295
296 return sprintf(buf, "%d %d %d %d [%s]\n",
297 jiffies_to_usecs(chip->timeout_a),
298 jiffies_to_usecs(chip->timeout_b),
299 jiffies_to_usecs(chip->timeout_c),
300 jiffies_to_usecs(chip->timeout_d),
301 chip->timeout_adjusted
302 ? "adjusted" : "original");
303 }
304 static DEVICE_ATTR_RO(timeouts);
305
tpm_version_major_show(struct device * dev,struct device_attribute * attr,char * buf)306 static ssize_t tpm_version_major_show(struct device *dev,
307 struct device_attribute *attr, char *buf)
308 {
309 struct tpm_chip *chip = to_tpm_chip(dev);
310
311 return sprintf(buf, "%s\n", chip->flags & TPM_CHIP_FLAG_TPM2
312 ? "2" : "1");
313 }
314 static DEVICE_ATTR_RO(tpm_version_major);
315
316 #ifdef CONFIG_TCG_TPM2_HMAC
null_name_show(struct device * dev,struct device_attribute * attr,char * buf)317 static ssize_t null_name_show(struct device *dev, struct device_attribute *attr,
318 char *buf)
319 {
320 struct tpm_chip *chip = to_tpm_chip(dev);
321 int size = TPM2_NAME_SIZE;
322
323 bin2hex(buf, chip->null_key_name, size);
324 size *= 2;
325 buf[size++] = '\n';
326 return size;
327 }
328 static DEVICE_ATTR_RO(null_name);
329 #endif
330
331 static struct attribute *tpm1_dev_attrs[] = {
332 &dev_attr_pubek.attr,
333 &dev_attr_pcrs.attr,
334 &dev_attr_enabled.attr,
335 &dev_attr_active.attr,
336 &dev_attr_owned.attr,
337 &dev_attr_temp_deactivated.attr,
338 &dev_attr_caps.attr,
339 &dev_attr_cancel.attr,
340 &dev_attr_durations.attr,
341 &dev_attr_timeouts.attr,
342 &dev_attr_tpm_version_major.attr,
343 NULL,
344 };
345
346 static struct attribute *tpm2_dev_attrs[] = {
347 &dev_attr_tpm_version_major.attr,
348 #ifdef CONFIG_TCG_TPM2_HMAC
349 &dev_attr_null_name.attr,
350 #endif
351 NULL
352 };
353
354 static const struct attribute_group tpm1_dev_group = {
355 .attrs = tpm1_dev_attrs,
356 };
357
358 static const struct attribute_group tpm2_dev_group = {
359 .attrs = tpm2_dev_attrs,
360 };
361
362 struct tpm_pcr_attr {
363 int alg_id;
364 int pcr;
365 struct device_attribute attr;
366 };
367
368 #define to_tpm_pcr_attr(a) container_of(a, struct tpm_pcr_attr, attr)
369
pcr_value_show(struct device * dev,struct device_attribute * attr,char * buf)370 static ssize_t pcr_value_show(struct device *dev,
371 struct device_attribute *attr,
372 char *buf)
373 {
374 struct tpm_pcr_attr *ha = to_tpm_pcr_attr(attr);
375 struct tpm_chip *chip = to_tpm_chip(dev);
376 struct tpm_digest digest;
377 int i;
378 int digest_size = 0;
379 int rc;
380 char *str = buf;
381
382 for (i = 0; i < chip->nr_allocated_banks; i++)
383 if (ha->alg_id == chip->allocated_banks[i].alg_id)
384 digest_size = chip->allocated_banks[i].digest_size;
385 /* should never happen */
386 if (!digest_size)
387 return -EINVAL;
388
389 digest.alg_id = ha->alg_id;
390 rc = tpm_pcr_read(chip, ha->pcr, &digest);
391 if (rc)
392 return rc;
393 for (i = 0; i < digest_size; i++)
394 str += sprintf(str, "%02X", digest.digest[i]);
395 str += sprintf(str, "\n");
396
397 return str - buf;
398 }
399
400 /*
401 * The following set of defines represents all the magic to build
402 * the per hash attribute groups for displaying each bank of PCRs.
403 * The only slight problem with this approach is that every PCR is
404 * hard coded to be present, so you don't know if an PCR is missing
405 * until a cat of the file returns -EINVAL
406 *
407 * Also note you must ignore checkpatch warnings in this macro
408 * code. This is deep macro magic that checkpatch.pl doesn't
409 * understand.
410 */
411
412 /* Note, this must match TPM2_PLATFORM_PCR which is fixed at 24. */
413 #define _TPM_HELPER(_alg, _hash, F) \
414 F(_alg, _hash, 0) \
415 F(_alg, _hash, 1) \
416 F(_alg, _hash, 2) \
417 F(_alg, _hash, 3) \
418 F(_alg, _hash, 4) \
419 F(_alg, _hash, 5) \
420 F(_alg, _hash, 6) \
421 F(_alg, _hash, 7) \
422 F(_alg, _hash, 8) \
423 F(_alg, _hash, 9) \
424 F(_alg, _hash, 10) \
425 F(_alg, _hash, 11) \
426 F(_alg, _hash, 12) \
427 F(_alg, _hash, 13) \
428 F(_alg, _hash, 14) \
429 F(_alg, _hash, 15) \
430 F(_alg, _hash, 16) \
431 F(_alg, _hash, 17) \
432 F(_alg, _hash, 18) \
433 F(_alg, _hash, 19) \
434 F(_alg, _hash, 20) \
435 F(_alg, _hash, 21) \
436 F(_alg, _hash, 22) \
437 F(_alg, _hash, 23)
438
439 /* ignore checkpatch warning about trailing ; in macro. */
440 #define PCR_ATTR(_alg, _hash, _pcr) \
441 static struct tpm_pcr_attr dev_attr_pcr_##_hash##_##_pcr = { \
442 .alg_id = _alg, \
443 .pcr = _pcr, \
444 .attr = { \
445 .attr = { \
446 .name = __stringify(_pcr), \
447 .mode = 0444 \
448 }, \
449 .show = pcr_value_show \
450 } \
451 };
452
453 #define PCR_ATTRS(_alg, _hash) \
454 _TPM_HELPER(_alg, _hash, PCR_ATTR)
455
456 /* ignore checkpatch warning about trailing , in macro. */
457 #define PCR_ATTR_VAL(_alg, _hash, _pcr) \
458 &dev_attr_pcr_##_hash##_##_pcr.attr.attr,
459
460 #define PCR_ATTR_GROUP_ARRAY(_alg, _hash) \
461 static struct attribute *pcr_group_attrs_##_hash[] = { \
462 _TPM_HELPER(_alg, _hash, PCR_ATTR_VAL) \
463 NULL \
464 }
465
466 #define PCR_ATTR_GROUP(_alg, _hash) \
467 static struct attribute_group pcr_group_##_hash = { \
468 .name = "pcr-" __stringify(_hash), \
469 .attrs = pcr_group_attrs_##_hash \
470 }
471
472 #define PCR_ATTR_BUILD(_alg, _hash) \
473 PCR_ATTRS(_alg, _hash) \
474 PCR_ATTR_GROUP_ARRAY(_alg, _hash); \
475 PCR_ATTR_GROUP(_alg, _hash)
476 /*
477 * End of macro structure to build an attribute group containing 24
478 * PCR value files for each supported hash algorithm
479 */
480
481 /*
482 * The next set of macros implements the cleverness for each hash to
483 * build a static attribute group called pcr_group_<hash> which can be
484 * added to chip->groups[].
485 *
486 * The first argument is the TPM algorithm id and the second is the
487 * hash used as both the suffix and the group name. Note: the group
488 * name is a directory in the top level tpm class with the name
489 * pcr-<hash>, so it must not clash with any other names already
490 * in the sysfs directory.
491 */
492 PCR_ATTR_BUILD(TPM_ALG_SHA1, sha1);
493 PCR_ATTR_BUILD(TPM_ALG_SHA256, sha256);
494 PCR_ATTR_BUILD(TPM_ALG_SHA384, sha384);
495 PCR_ATTR_BUILD(TPM_ALG_SHA512, sha512);
496 PCR_ATTR_BUILD(TPM_ALG_SM3_256, sm3);
497
498
tpm_sysfs_add_device(struct tpm_chip * chip)499 void tpm_sysfs_add_device(struct tpm_chip *chip)
500 {
501 int i;
502
503 WARN_ON(chip->groups_cnt != 0);
504
505 if (tpm_is_firmware_upgrade(chip))
506 return;
507
508 if (chip->flags & TPM_CHIP_FLAG_TPM2)
509 chip->groups[chip->groups_cnt++] = &tpm2_dev_group;
510 else
511 chip->groups[chip->groups_cnt++] = &tpm1_dev_group;
512
513 /* add one group for each bank hash */
514 for (i = 0; i < chip->nr_allocated_banks; i++) {
515 switch (chip->allocated_banks[i].alg_id) {
516 case TPM_ALG_SHA1:
517 chip->groups[chip->groups_cnt++] = &pcr_group_sha1;
518 break;
519 case TPM_ALG_SHA256:
520 chip->groups[chip->groups_cnt++] = &pcr_group_sha256;
521 break;
522 case TPM_ALG_SHA384:
523 chip->groups[chip->groups_cnt++] = &pcr_group_sha384;
524 break;
525 case TPM_ALG_SHA512:
526 chip->groups[chip->groups_cnt++] = &pcr_group_sha512;
527 break;
528 case TPM_ALG_SM3_256:
529 chip->groups[chip->groups_cnt++] = &pcr_group_sm3;
530 break;
531 default:
532 /*
533 * If triggers, send a patch to add both a
534 * PCR_ATTR_BUILD() macro above for the
535 * missing algorithm as well as an additional
536 * case in this switch statement.
537 */
538 dev_err(&chip->dev,
539 "TPM with unsupported bank algorithm 0x%04x",
540 chip->allocated_banks[i].alg_id);
541 break;
542 }
543 }
544
545 /*
546 * This will only trigger if someone has added an additional
547 * hash to the tpm_algorithms enum without incrementing
548 * TPM_MAX_HASHES.
549 */
550 WARN_ON(chip->groups_cnt > TPM_MAX_HASHES + 1);
551 }
552