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