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Merge branches 'for-4.11/upstream-fixes', 'for-4.12/accutouch', 'for-4.12/cp2112...
[mirror_ubuntu-artful-kernel.git] / drivers / char / tpm / tpm-interface.c
1 /*
2 * Copyright (C) 2004 IBM Corporation
3 * Copyright (C) 2014 Intel Corporation
4 *
5 * Authors:
6 * Leendert van Doorn <leendert@watson.ibm.com>
7 * Dave Safford <safford@watson.ibm.com>
8 * Reiner Sailer <sailer@watson.ibm.com>
9 * Kylene Hall <kjhall@us.ibm.com>
10 *
11 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
12 *
13 * Device driver for TCG/TCPA TPM (trusted platform module).
14 * Specifications at www.trustedcomputinggroup.org
15 *
16 * This program is free software; you can redistribute it and/or
17 * modify it under the terms of the GNU General Public License as
18 * published by the Free Software Foundation, version 2 of the
19 * License.
20 *
21 * Note, the TPM chip is not interrupt driven (only polling)
22 * and can have very long timeouts (minutes!). Hence the unusual
23 * calls to msleep.
24 *
25 */
26
27 #include <linux/poll.h>
28 #include <linux/slab.h>
29 #include <linux/mutex.h>
30 #include <linux/spinlock.h>
31 #include <linux/freezer.h>
32 #include <linux/pm_runtime.h>
33
34 #include "tpm.h"
35 #include "tpm_eventlog.h"
36
37 #define TPM_MAX_ORDINAL 243
38 #define TSC_MAX_ORDINAL 12
39 #define TPM_PROTECTED_COMMAND 0x00
40 #define TPM_CONNECTION_COMMAND 0x40
41
42 /*
43 * Bug workaround - some TPM's don't flush the most
44 * recently changed pcr on suspend, so force the flush
45 * with an extend to the selected _unused_ non-volatile pcr.
46 */
47 static int tpm_suspend_pcr;
48 module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644);
49 MODULE_PARM_DESC(suspend_pcr,
50 "PCR to use for dummy writes to facilitate flush on suspend.");
51
52 /*
53 * Array with one entry per ordinal defining the maximum amount
54 * of time the chip could take to return the result. The ordinal
55 * designation of short, medium or long is defined in a table in
56 * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
57 * values of the SHORT, MEDIUM, and LONG durations are retrieved
58 * from the chip during initialization with a call to tpm_get_timeouts.
59 */
60 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
61 TPM_UNDEFINED, /* 0 */
62 TPM_UNDEFINED,
63 TPM_UNDEFINED,
64 TPM_UNDEFINED,
65 TPM_UNDEFINED,
66 TPM_UNDEFINED, /* 5 */
67 TPM_UNDEFINED,
68 TPM_UNDEFINED,
69 TPM_UNDEFINED,
70 TPM_UNDEFINED,
71 TPM_SHORT, /* 10 */
72 TPM_SHORT,
73 TPM_MEDIUM,
74 TPM_LONG,
75 TPM_LONG,
76 TPM_MEDIUM, /* 15 */
77 TPM_SHORT,
78 TPM_SHORT,
79 TPM_MEDIUM,
80 TPM_LONG,
81 TPM_SHORT, /* 20 */
82 TPM_SHORT,
83 TPM_MEDIUM,
84 TPM_MEDIUM,
85 TPM_MEDIUM,
86 TPM_SHORT, /* 25 */
87 TPM_SHORT,
88 TPM_MEDIUM,
89 TPM_SHORT,
90 TPM_SHORT,
91 TPM_MEDIUM, /* 30 */
92 TPM_LONG,
93 TPM_MEDIUM,
94 TPM_SHORT,
95 TPM_SHORT,
96 TPM_SHORT, /* 35 */
97 TPM_MEDIUM,
98 TPM_MEDIUM,
99 TPM_UNDEFINED,
100 TPM_UNDEFINED,
101 TPM_MEDIUM, /* 40 */
102 TPM_LONG,
103 TPM_MEDIUM,
104 TPM_SHORT,
105 TPM_SHORT,
106 TPM_SHORT, /* 45 */
107 TPM_SHORT,
108 TPM_SHORT,
109 TPM_SHORT,
110 TPM_LONG,
111 TPM_MEDIUM, /* 50 */
112 TPM_MEDIUM,
113 TPM_UNDEFINED,
114 TPM_UNDEFINED,
115 TPM_UNDEFINED,
116 TPM_UNDEFINED, /* 55 */
117 TPM_UNDEFINED,
118 TPM_UNDEFINED,
119 TPM_UNDEFINED,
120 TPM_UNDEFINED,
121 TPM_MEDIUM, /* 60 */
122 TPM_MEDIUM,
123 TPM_MEDIUM,
124 TPM_SHORT,
125 TPM_SHORT,
126 TPM_MEDIUM, /* 65 */
127 TPM_UNDEFINED,
128 TPM_UNDEFINED,
129 TPM_UNDEFINED,
130 TPM_UNDEFINED,
131 TPM_SHORT, /* 70 */
132 TPM_SHORT,
133 TPM_UNDEFINED,
134 TPM_UNDEFINED,
135 TPM_UNDEFINED,
136 TPM_UNDEFINED, /* 75 */
137 TPM_UNDEFINED,
138 TPM_UNDEFINED,
139 TPM_UNDEFINED,
140 TPM_UNDEFINED,
141 TPM_LONG, /* 80 */
142 TPM_UNDEFINED,
143 TPM_MEDIUM,
144 TPM_LONG,
145 TPM_SHORT,
146 TPM_UNDEFINED, /* 85 */
147 TPM_UNDEFINED,
148 TPM_UNDEFINED,
149 TPM_UNDEFINED,
150 TPM_UNDEFINED,
151 TPM_SHORT, /* 90 */
152 TPM_SHORT,
153 TPM_SHORT,
154 TPM_SHORT,
155 TPM_SHORT,
156 TPM_UNDEFINED, /* 95 */
157 TPM_UNDEFINED,
158 TPM_UNDEFINED,
159 TPM_UNDEFINED,
160 TPM_UNDEFINED,
161 TPM_MEDIUM, /* 100 */
162 TPM_SHORT,
163 TPM_SHORT,
164 TPM_UNDEFINED,
165 TPM_UNDEFINED,
166 TPM_UNDEFINED, /* 105 */
167 TPM_UNDEFINED,
168 TPM_UNDEFINED,
169 TPM_UNDEFINED,
170 TPM_UNDEFINED,
171 TPM_SHORT, /* 110 */
172 TPM_SHORT,
173 TPM_SHORT,
174 TPM_SHORT,
175 TPM_SHORT,
176 TPM_SHORT, /* 115 */
177 TPM_SHORT,
178 TPM_SHORT,
179 TPM_UNDEFINED,
180 TPM_UNDEFINED,
181 TPM_LONG, /* 120 */
182 TPM_LONG,
183 TPM_MEDIUM,
184 TPM_UNDEFINED,
185 TPM_SHORT,
186 TPM_SHORT, /* 125 */
187 TPM_SHORT,
188 TPM_LONG,
189 TPM_SHORT,
190 TPM_SHORT,
191 TPM_SHORT, /* 130 */
192 TPM_MEDIUM,
193 TPM_UNDEFINED,
194 TPM_SHORT,
195 TPM_MEDIUM,
196 TPM_UNDEFINED, /* 135 */
197 TPM_UNDEFINED,
198 TPM_UNDEFINED,
199 TPM_UNDEFINED,
200 TPM_UNDEFINED,
201 TPM_SHORT, /* 140 */
202 TPM_SHORT,
203 TPM_UNDEFINED,
204 TPM_UNDEFINED,
205 TPM_UNDEFINED,
206 TPM_UNDEFINED, /* 145 */
207 TPM_UNDEFINED,
208 TPM_UNDEFINED,
209 TPM_UNDEFINED,
210 TPM_UNDEFINED,
211 TPM_SHORT, /* 150 */
212 TPM_MEDIUM,
213 TPM_MEDIUM,
214 TPM_SHORT,
215 TPM_SHORT,
216 TPM_UNDEFINED, /* 155 */
217 TPM_UNDEFINED,
218 TPM_UNDEFINED,
219 TPM_UNDEFINED,
220 TPM_UNDEFINED,
221 TPM_SHORT, /* 160 */
222 TPM_SHORT,
223 TPM_SHORT,
224 TPM_SHORT,
225 TPM_UNDEFINED,
226 TPM_UNDEFINED, /* 165 */
227 TPM_UNDEFINED,
228 TPM_UNDEFINED,
229 TPM_UNDEFINED,
230 TPM_UNDEFINED,
231 TPM_LONG, /* 170 */
232 TPM_UNDEFINED,
233 TPM_UNDEFINED,
234 TPM_UNDEFINED,
235 TPM_UNDEFINED,
236 TPM_UNDEFINED, /* 175 */
237 TPM_UNDEFINED,
238 TPM_UNDEFINED,
239 TPM_UNDEFINED,
240 TPM_UNDEFINED,
241 TPM_MEDIUM, /* 180 */
242 TPM_SHORT,
243 TPM_MEDIUM,
244 TPM_MEDIUM,
245 TPM_MEDIUM,
246 TPM_MEDIUM, /* 185 */
247 TPM_SHORT,
248 TPM_UNDEFINED,
249 TPM_UNDEFINED,
250 TPM_UNDEFINED,
251 TPM_UNDEFINED, /* 190 */
252 TPM_UNDEFINED,
253 TPM_UNDEFINED,
254 TPM_UNDEFINED,
255 TPM_UNDEFINED,
256 TPM_UNDEFINED, /* 195 */
257 TPM_UNDEFINED,
258 TPM_UNDEFINED,
259 TPM_UNDEFINED,
260 TPM_UNDEFINED,
261 TPM_SHORT, /* 200 */
262 TPM_UNDEFINED,
263 TPM_UNDEFINED,
264 TPM_UNDEFINED,
265 TPM_SHORT,
266 TPM_SHORT, /* 205 */
267 TPM_SHORT,
268 TPM_SHORT,
269 TPM_SHORT,
270 TPM_SHORT,
271 TPM_MEDIUM, /* 210 */
272 TPM_UNDEFINED,
273 TPM_MEDIUM,
274 TPM_MEDIUM,
275 TPM_MEDIUM,
276 TPM_UNDEFINED, /* 215 */
277 TPM_MEDIUM,
278 TPM_UNDEFINED,
279 TPM_UNDEFINED,
280 TPM_SHORT,
281 TPM_SHORT, /* 220 */
282 TPM_SHORT,
283 TPM_SHORT,
284 TPM_SHORT,
285 TPM_SHORT,
286 TPM_UNDEFINED, /* 225 */
287 TPM_UNDEFINED,
288 TPM_UNDEFINED,
289 TPM_UNDEFINED,
290 TPM_UNDEFINED,
291 TPM_SHORT, /* 230 */
292 TPM_LONG,
293 TPM_MEDIUM,
294 TPM_UNDEFINED,
295 TPM_UNDEFINED,
296 TPM_UNDEFINED, /* 235 */
297 TPM_UNDEFINED,
298 TPM_UNDEFINED,
299 TPM_UNDEFINED,
300 TPM_UNDEFINED,
301 TPM_SHORT, /* 240 */
302 TPM_UNDEFINED,
303 TPM_MEDIUM,
304 };
305
306 /*
307 * Returns max number of jiffies to wait
308 */
309 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
310 u32 ordinal)
311 {
312 int duration_idx = TPM_UNDEFINED;
313 int duration = 0;
314
315 /*
316 * We only have a duration table for protected commands, where the upper
317 * 16 bits are 0. For the few other ordinals the fallback will be used.
318 */
319 if (ordinal < TPM_MAX_ORDINAL)
320 duration_idx = tpm_ordinal_duration[ordinal];
321
322 if (duration_idx != TPM_UNDEFINED)
323 duration = chip->duration[duration_idx];
324 if (duration <= 0)
325 return 2 * 60 * HZ;
326 else
327 return duration;
328 }
329 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
330
331 /**
332 * tmp_transmit - Internal kernel interface to transmit TPM commands.
333 *
334 * @chip: TPM chip to use
335 * @buf: TPM command buffer
336 * @bufsiz: length of the TPM command buffer
337 * @flags: tpm transmit flags - bitmap
338 *
339 * Return:
340 * 0 when the operation is successful.
341 * A negative number for system errors (errno).
342 */
343 ssize_t tpm_transmit(struct tpm_chip *chip, const u8 *buf, size_t bufsiz,
344 unsigned int flags)
345 {
346 ssize_t rc;
347 u32 count, ordinal;
348 unsigned long stop;
349
350 if (bufsiz < TPM_HEADER_SIZE)
351 return -EINVAL;
352
353 if (bufsiz > TPM_BUFSIZE)
354 bufsiz = TPM_BUFSIZE;
355
356 count = be32_to_cpu(*((__be32 *) (buf + 2)));
357 ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
358 if (count == 0)
359 return -ENODATA;
360 if (count > bufsiz) {
361 dev_err(&chip->dev,
362 "invalid count value %x %zx\n", count, bufsiz);
363 return -E2BIG;
364 }
365
366 if (!(flags & TPM_TRANSMIT_UNLOCKED))
367 mutex_lock(&chip->tpm_mutex);
368
369 if (chip->dev.parent)
370 pm_runtime_get_sync(chip->dev.parent);
371
372 rc = chip->ops->send(chip, (u8 *) buf, count);
373 if (rc < 0) {
374 dev_err(&chip->dev,
375 "tpm_transmit: tpm_send: error %zd\n", rc);
376 goto out;
377 }
378
379 if (chip->flags & TPM_CHIP_FLAG_IRQ)
380 goto out_recv;
381
382 if (chip->flags & TPM_CHIP_FLAG_TPM2)
383 stop = jiffies + tpm2_calc_ordinal_duration(chip, ordinal);
384 else
385 stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
386 do {
387 u8 status = chip->ops->status(chip);
388 if ((status & chip->ops->req_complete_mask) ==
389 chip->ops->req_complete_val)
390 goto out_recv;
391
392 if (chip->ops->req_canceled(chip, status)) {
393 dev_err(&chip->dev, "Operation Canceled\n");
394 rc = -ECANCELED;
395 goto out;
396 }
397
398 msleep(TPM_TIMEOUT); /* CHECK */
399 rmb();
400 } while (time_before(jiffies, stop));
401
402 chip->ops->cancel(chip);
403 dev_err(&chip->dev, "Operation Timed out\n");
404 rc = -ETIME;
405 goto out;
406
407 out_recv:
408 rc = chip->ops->recv(chip, (u8 *) buf, bufsiz);
409 if (rc < 0)
410 dev_err(&chip->dev,
411 "tpm_transmit: tpm_recv: error %zd\n", rc);
412 out:
413 if (chip->dev.parent)
414 pm_runtime_put_sync(chip->dev.parent);
415
416 if (!(flags & TPM_TRANSMIT_UNLOCKED))
417 mutex_unlock(&chip->tpm_mutex);
418 return rc;
419 }
420
421 /**
422 * tmp_transmit_cmd - send a tpm command to the device
423 * The function extracts tpm out header return code
424 *
425 * @chip: TPM chip to use
426 * @buf: TPM command buffer
427 * @bufsiz: length of the buffer
428 * @min_rsp_body_length: minimum expected length of response body
429 * @flags: tpm transmit flags - bitmap
430 * @desc: command description used in the error message
431 *
432 * Return:
433 * 0 when the operation is successful.
434 * A negative number for system errors (errno).
435 * A positive number for a TPM error.
436 */
437 ssize_t tpm_transmit_cmd(struct tpm_chip *chip, const void *buf,
438 size_t bufsiz, size_t min_rsp_body_length,
439 unsigned int flags, const char *desc)
440 {
441 const struct tpm_output_header *header;
442 int err;
443 ssize_t len;
444
445 len = tpm_transmit(chip, (const u8 *)buf, bufsiz, flags);
446 if (len < 0)
447 return len;
448 else if (len < TPM_HEADER_SIZE)
449 return -EFAULT;
450
451 header = buf;
452 if (len != be32_to_cpu(header->length))
453 return -EFAULT;
454
455 err = be32_to_cpu(header->return_code);
456 if (err != 0 && desc)
457 dev_err(&chip->dev, "A TPM error (%d) occurred %s\n", err,
458 desc);
459 if (err)
460 return err;
461
462 if (len < min_rsp_body_length + TPM_HEADER_SIZE)
463 return -EFAULT;
464
465 return 0;
466 }
467
468 #define TPM_DIGEST_SIZE 20
469 #define TPM_RET_CODE_IDX 6
470 #define TPM_INTERNAL_RESULT_SIZE 200
471 #define TPM_ORD_GET_CAP cpu_to_be32(101)
472 #define TPM_ORD_GET_RANDOM cpu_to_be32(70)
473
474 static const struct tpm_input_header tpm_getcap_header = {
475 .tag = TPM_TAG_RQU_COMMAND,
476 .length = cpu_to_be32(22),
477 .ordinal = TPM_ORD_GET_CAP
478 };
479
480 ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
481 const char *desc, size_t min_cap_length)
482 {
483 struct tpm_cmd_t tpm_cmd;
484 int rc;
485
486 tpm_cmd.header.in = tpm_getcap_header;
487 if (subcap_id == TPM_CAP_VERSION_1_1 ||
488 subcap_id == TPM_CAP_VERSION_1_2) {
489 tpm_cmd.params.getcap_in.cap = cpu_to_be32(subcap_id);
490 /*subcap field not necessary */
491 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
492 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
493 } else {
494 if (subcap_id == TPM_CAP_FLAG_PERM ||
495 subcap_id == TPM_CAP_FLAG_VOL)
496 tpm_cmd.params.getcap_in.cap =
497 cpu_to_be32(TPM_CAP_FLAG);
498 else
499 tpm_cmd.params.getcap_in.cap =
500 cpu_to_be32(TPM_CAP_PROP);
501 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
502 tpm_cmd.params.getcap_in.subcap = cpu_to_be32(subcap_id);
503 }
504 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
505 min_cap_length, 0, desc);
506 if (!rc)
507 *cap = tpm_cmd.params.getcap_out.cap;
508 return rc;
509 }
510 EXPORT_SYMBOL_GPL(tpm_getcap);
511
512 #define TPM_ORD_STARTUP cpu_to_be32(153)
513 #define TPM_ST_CLEAR cpu_to_be16(1)
514 #define TPM_ST_STATE cpu_to_be16(2)
515 #define TPM_ST_DEACTIVATED cpu_to_be16(3)
516 static const struct tpm_input_header tpm_startup_header = {
517 .tag = TPM_TAG_RQU_COMMAND,
518 .length = cpu_to_be32(12),
519 .ordinal = TPM_ORD_STARTUP
520 };
521
522 static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
523 {
524 struct tpm_cmd_t start_cmd;
525 start_cmd.header.in = tpm_startup_header;
526
527 start_cmd.params.startup_in.startup_type = startup_type;
528 return tpm_transmit_cmd(chip, &start_cmd, TPM_INTERNAL_RESULT_SIZE, 0,
529 0, "attempting to start the TPM");
530 }
531
532 int tpm_get_timeouts(struct tpm_chip *chip)
533 {
534 cap_t cap;
535 unsigned long timeout_old[4], timeout_chip[4], timeout_eff[4];
536 ssize_t rc;
537
538 if (chip->flags & TPM_CHIP_FLAG_HAVE_TIMEOUTS)
539 return 0;
540
541 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
542 /* Fixed timeouts for TPM2 */
543 chip->timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
544 chip->timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
545 chip->timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
546 chip->timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
547 chip->duration[TPM_SHORT] =
548 msecs_to_jiffies(TPM2_DURATION_SHORT);
549 chip->duration[TPM_MEDIUM] =
550 msecs_to_jiffies(TPM2_DURATION_MEDIUM);
551 chip->duration[TPM_LONG] =
552 msecs_to_jiffies(TPM2_DURATION_LONG);
553
554 chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
555 return 0;
556 }
557
558 rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, NULL,
559 sizeof(cap.timeout));
560 if (rc == TPM_ERR_INVALID_POSTINIT) {
561 /* The TPM is not started, we are the first to talk to it.
562 Execute a startup command. */
563 dev_info(&chip->dev, "Issuing TPM_STARTUP\n");
564 if (tpm_startup(chip, TPM_ST_CLEAR))
565 return rc;
566
567 rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
568 "attempting to determine the timeouts",
569 sizeof(cap.timeout));
570 }
571
572 if (rc) {
573 dev_err(&chip->dev,
574 "A TPM error (%zd) occurred attempting to determine the timeouts\n",
575 rc);
576 return rc;
577 }
578
579 timeout_old[0] = jiffies_to_usecs(chip->timeout_a);
580 timeout_old[1] = jiffies_to_usecs(chip->timeout_b);
581 timeout_old[2] = jiffies_to_usecs(chip->timeout_c);
582 timeout_old[3] = jiffies_to_usecs(chip->timeout_d);
583 timeout_chip[0] = be32_to_cpu(cap.timeout.a);
584 timeout_chip[1] = be32_to_cpu(cap.timeout.b);
585 timeout_chip[2] = be32_to_cpu(cap.timeout.c);
586 timeout_chip[3] = be32_to_cpu(cap.timeout.d);
587 memcpy(timeout_eff, timeout_chip, sizeof(timeout_eff));
588
589 /*
590 * Provide ability for vendor overrides of timeout values in case
591 * of misreporting.
592 */
593 if (chip->ops->update_timeouts != NULL)
594 chip->timeout_adjusted =
595 chip->ops->update_timeouts(chip, timeout_eff);
596
597 if (!chip->timeout_adjusted) {
598 /* Restore default if chip reported 0 */
599 int i;
600
601 for (i = 0; i < ARRAY_SIZE(timeout_eff); i++) {
602 if (timeout_eff[i])
603 continue;
604
605 timeout_eff[i] = timeout_old[i];
606 chip->timeout_adjusted = true;
607 }
608
609 if (timeout_eff[0] != 0 && timeout_eff[0] < 1000) {
610 /* timeouts in msec rather usec */
611 for (i = 0; i != ARRAY_SIZE(timeout_eff); i++)
612 timeout_eff[i] *= 1000;
613 chip->timeout_adjusted = true;
614 }
615 }
616
617 /* Report adjusted timeouts */
618 if (chip->timeout_adjusted) {
619 dev_info(&chip->dev,
620 HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n",
621 timeout_chip[0], timeout_eff[0],
622 timeout_chip[1], timeout_eff[1],
623 timeout_chip[2], timeout_eff[2],
624 timeout_chip[3], timeout_eff[3]);
625 }
626
627 chip->timeout_a = usecs_to_jiffies(timeout_eff[0]);
628 chip->timeout_b = usecs_to_jiffies(timeout_eff[1]);
629 chip->timeout_c = usecs_to_jiffies(timeout_eff[2]);
630 chip->timeout_d = usecs_to_jiffies(timeout_eff[3]);
631
632 rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap,
633 "attempting to determine the durations",
634 sizeof(cap.duration));
635 if (rc)
636 return rc;
637
638 chip->duration[TPM_SHORT] =
639 usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short));
640 chip->duration[TPM_MEDIUM] =
641 usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium));
642 chip->duration[TPM_LONG] =
643 usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long));
644
645 /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
646 * value wrong and apparently reports msecs rather than usecs. So we
647 * fix up the resulting too-small TPM_SHORT value to make things work.
648 * We also scale the TPM_MEDIUM and -_LONG values by 1000.
649 */
650 if (chip->duration[TPM_SHORT] < (HZ / 100)) {
651 chip->duration[TPM_SHORT] = HZ;
652 chip->duration[TPM_MEDIUM] *= 1000;
653 chip->duration[TPM_LONG] *= 1000;
654 chip->duration_adjusted = true;
655 dev_info(&chip->dev, "Adjusting TPM timeout parameters.");
656 }
657
658 chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
659 return 0;
660 }
661 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
662
663 #define TPM_ORD_CONTINUE_SELFTEST 83
664 #define CONTINUE_SELFTEST_RESULT_SIZE 10
665
666 static const struct tpm_input_header continue_selftest_header = {
667 .tag = TPM_TAG_RQU_COMMAND,
668 .length = cpu_to_be32(10),
669 .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
670 };
671
672 /**
673 * tpm_continue_selftest -- run TPM's selftest
674 * @chip: TPM chip to use
675 *
676 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
677 * a TPM error code.
678 */
679 static int tpm_continue_selftest(struct tpm_chip *chip)
680 {
681 int rc;
682 struct tpm_cmd_t cmd;
683
684 cmd.header.in = continue_selftest_header;
685 rc = tpm_transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE, 0, 0,
686 "continue selftest");
687 return rc;
688 }
689
690 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
691 #define READ_PCR_RESULT_SIZE 30
692 #define READ_PCR_RESULT_BODY_SIZE 20
693 static const struct tpm_input_header pcrread_header = {
694 .tag = TPM_TAG_RQU_COMMAND,
695 .length = cpu_to_be32(14),
696 .ordinal = TPM_ORDINAL_PCRREAD
697 };
698
699 int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
700 {
701 int rc;
702 struct tpm_cmd_t cmd;
703
704 cmd.header.in = pcrread_header;
705 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
706 rc = tpm_transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
707 READ_PCR_RESULT_BODY_SIZE, 0,
708 "attempting to read a pcr value");
709
710 if (rc == 0)
711 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
712 TPM_DIGEST_SIZE);
713 return rc;
714 }
715
716 /**
717 * tpm_is_tpm2 - is the chip a TPM2 chip?
718 * @chip_num: tpm idx # or ANY
719 *
720 * Returns < 0 on error, and 1 or 0 on success depending whether the chip
721 * is a TPM2 chip.
722 */
723 int tpm_is_tpm2(u32 chip_num)
724 {
725 struct tpm_chip *chip;
726 int rc;
727
728 chip = tpm_chip_find_get(chip_num);
729 if (chip == NULL)
730 return -ENODEV;
731
732 rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0;
733
734 tpm_put_ops(chip);
735
736 return rc;
737 }
738 EXPORT_SYMBOL_GPL(tpm_is_tpm2);
739
740 /**
741 * tpm_pcr_read - read a pcr value
742 * @chip_num: tpm idx # or ANY
743 * @pcr_idx: pcr idx to retrieve
744 * @res_buf: TPM_PCR value
745 * size of res_buf is 20 bytes (or NULL if you don't care)
746 *
747 * The TPM driver should be built-in, but for whatever reason it
748 * isn't, protect against the chip disappearing, by incrementing
749 * the module usage count.
750 */
751 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
752 {
753 struct tpm_chip *chip;
754 int rc;
755
756 chip = tpm_chip_find_get(chip_num);
757 if (chip == NULL)
758 return -ENODEV;
759 if (chip->flags & TPM_CHIP_FLAG_TPM2)
760 rc = tpm2_pcr_read(chip, pcr_idx, res_buf);
761 else
762 rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf);
763 tpm_put_ops(chip);
764 return rc;
765 }
766 EXPORT_SYMBOL_GPL(tpm_pcr_read);
767
768 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
769 #define EXTEND_PCR_RESULT_SIZE 34
770 #define EXTEND_PCR_RESULT_BODY_SIZE 20
771 static const struct tpm_input_header pcrextend_header = {
772 .tag = TPM_TAG_RQU_COMMAND,
773 .length = cpu_to_be32(34),
774 .ordinal = TPM_ORD_PCR_EXTEND
775 };
776
777 /**
778 * tpm_pcr_extend - extend pcr value with hash
779 * @chip_num: tpm idx # or AN&
780 * @pcr_idx: pcr idx to extend
781 * @hash: hash value used to extend pcr value
782 *
783 * The TPM driver should be built-in, but for whatever reason it
784 * isn't, protect against the chip disappearing, by incrementing
785 * the module usage count.
786 */
787 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
788 {
789 struct tpm_cmd_t cmd;
790 int rc;
791 struct tpm_chip *chip;
792 struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)];
793 u32 count = 0;
794 int i;
795
796 chip = tpm_chip_find_get(chip_num);
797 if (chip == NULL)
798 return -ENODEV;
799
800 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
801 memset(digest_list, 0, sizeof(digest_list));
802
803 for (i = 0; i < ARRAY_SIZE(chip->active_banks) &&
804 chip->active_banks[i] != TPM2_ALG_ERROR; i++) {
805 digest_list[i].alg_id = chip->active_banks[i];
806 memcpy(digest_list[i].digest, hash, TPM_DIGEST_SIZE);
807 count++;
808 }
809
810 rc = tpm2_pcr_extend(chip, pcr_idx, count, digest_list);
811 tpm_put_ops(chip);
812 return rc;
813 }
814
815 cmd.header.in = pcrextend_header;
816 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
817 memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
818 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
819 EXTEND_PCR_RESULT_BODY_SIZE, 0,
820 "attempting extend a PCR value");
821
822 tpm_put_ops(chip);
823 return rc;
824 }
825 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
826
827 /**
828 * tpm_do_selftest - have the TPM continue its selftest and wait until it
829 * can receive further commands
830 * @chip: TPM chip to use
831 *
832 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
833 * a TPM error code.
834 */
835 int tpm_do_selftest(struct tpm_chip *chip)
836 {
837 int rc;
838 unsigned int loops;
839 unsigned int delay_msec = 100;
840 unsigned long duration;
841 u8 dummy[TPM_DIGEST_SIZE];
842
843 duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST);
844
845 loops = jiffies_to_msecs(duration) / delay_msec;
846
847 rc = tpm_continue_selftest(chip);
848 /* This may fail if there was no TPM driver during a suspend/resume
849 * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
850 */
851 if (rc)
852 return rc;
853
854 do {
855 /* Attempt to read a PCR value */
856 rc = tpm_pcr_read_dev(chip, 0, dummy);
857
858 /* Some buggy TPMs will not respond to tpm_tis_ready() for
859 * around 300ms while the self test is ongoing, keep trying
860 * until the self test duration expires. */
861 if (rc == -ETIME) {
862 dev_info(
863 &chip->dev, HW_ERR
864 "TPM command timed out during continue self test");
865 msleep(delay_msec);
866 continue;
867 }
868
869 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
870 dev_info(&chip->dev,
871 "TPM is disabled/deactivated (0x%X)\n", rc);
872 /* TPM is disabled and/or deactivated; driver can
873 * proceed and TPM does handle commands for
874 * suspend/resume correctly
875 */
876 return 0;
877 }
878 if (rc != TPM_WARN_DOING_SELFTEST)
879 return rc;
880 msleep(delay_msec);
881 } while (--loops > 0);
882
883 return rc;
884 }
885 EXPORT_SYMBOL_GPL(tpm_do_selftest);
886
887 /**
888 * tpm1_auto_startup - Perform the standard automatic TPM initialization
889 * sequence
890 * @chip: TPM chip to use
891 *
892 * Returns 0 on success, < 0 in case of fatal error.
893 */
894 int tpm1_auto_startup(struct tpm_chip *chip)
895 {
896 int rc;
897
898 rc = tpm_get_timeouts(chip);
899 if (rc)
900 goto out;
901 rc = tpm_do_selftest(chip);
902 if (rc) {
903 dev_err(&chip->dev, "TPM self test failed\n");
904 goto out;
905 }
906
907 return rc;
908 out:
909 if (rc > 0)
910 rc = -ENODEV;
911 return rc;
912 }
913
914 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
915 {
916 struct tpm_chip *chip;
917 int rc;
918
919 chip = tpm_chip_find_get(chip_num);
920 if (chip == NULL)
921 return -ENODEV;
922
923 rc = tpm_transmit_cmd(chip, cmd, buflen, 0, 0, "attempting tpm_cmd");
924
925 tpm_put_ops(chip);
926 return rc;
927 }
928 EXPORT_SYMBOL_GPL(tpm_send);
929
930 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
931 bool check_cancel, bool *canceled)
932 {
933 u8 status = chip->ops->status(chip);
934
935 *canceled = false;
936 if ((status & mask) == mask)
937 return true;
938 if (check_cancel && chip->ops->req_canceled(chip, status)) {
939 *canceled = true;
940 return true;
941 }
942 return false;
943 }
944
945 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
946 wait_queue_head_t *queue, bool check_cancel)
947 {
948 unsigned long stop;
949 long rc;
950 u8 status;
951 bool canceled = false;
952
953 /* check current status */
954 status = chip->ops->status(chip);
955 if ((status & mask) == mask)
956 return 0;
957
958 stop = jiffies + timeout;
959
960 if (chip->flags & TPM_CHIP_FLAG_IRQ) {
961 again:
962 timeout = stop - jiffies;
963 if ((long)timeout <= 0)
964 return -ETIME;
965 rc = wait_event_interruptible_timeout(*queue,
966 wait_for_tpm_stat_cond(chip, mask, check_cancel,
967 &canceled),
968 timeout);
969 if (rc > 0) {
970 if (canceled)
971 return -ECANCELED;
972 return 0;
973 }
974 if (rc == -ERESTARTSYS && freezing(current)) {
975 clear_thread_flag(TIF_SIGPENDING);
976 goto again;
977 }
978 } else {
979 do {
980 msleep(TPM_TIMEOUT);
981 status = chip->ops->status(chip);
982 if ((status & mask) == mask)
983 return 0;
984 } while (time_before(jiffies, stop));
985 }
986 return -ETIME;
987 }
988 EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
989
990 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
991 #define SAVESTATE_RESULT_SIZE 10
992
993 static const struct tpm_input_header savestate_header = {
994 .tag = TPM_TAG_RQU_COMMAND,
995 .length = cpu_to_be32(10),
996 .ordinal = TPM_ORD_SAVESTATE
997 };
998
999 /*
1000 * We are about to suspend. Save the TPM state
1001 * so that it can be restored.
1002 */
1003 int tpm_pm_suspend(struct device *dev)
1004 {
1005 struct tpm_chip *chip = dev_get_drvdata(dev);
1006 struct tpm_cmd_t cmd;
1007 int rc, try;
1008
1009 u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1010
1011 if (chip == NULL)
1012 return -ENODEV;
1013
1014 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
1015 tpm2_shutdown(chip, TPM2_SU_STATE);
1016 return 0;
1017 }
1018
1019 /* for buggy tpm, flush pcrs with extend to selected dummy */
1020 if (tpm_suspend_pcr) {
1021 cmd.header.in = pcrextend_header;
1022 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1023 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1024 TPM_DIGEST_SIZE);
1025 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1026 EXTEND_PCR_RESULT_BODY_SIZE, 0,
1027 "extending dummy pcr before suspend");
1028 }
1029
1030 /* now do the actual savestate */
1031 for (try = 0; try < TPM_RETRY; try++) {
1032 cmd.header.in = savestate_header;
1033 rc = tpm_transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, 0,
1034 0, NULL);
1035
1036 /*
1037 * If the TPM indicates that it is too busy to respond to
1038 * this command then retry before giving up. It can take
1039 * several seconds for this TPM to be ready.
1040 *
1041 * This can happen if the TPM has already been sent the
1042 * SaveState command before the driver has loaded. TCG 1.2
1043 * specification states that any communication after SaveState
1044 * may cause the TPM to invalidate previously saved state.
1045 */
1046 if (rc != TPM_WARN_RETRY)
1047 break;
1048 msleep(TPM_TIMEOUT_RETRY);
1049 }
1050
1051 if (rc)
1052 dev_err(&chip->dev,
1053 "Error (%d) sending savestate before suspend\n", rc);
1054 else if (try > 0)
1055 dev_warn(&chip->dev, "TPM savestate took %dms\n",
1056 try * TPM_TIMEOUT_RETRY);
1057
1058 return rc;
1059 }
1060 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1061
1062 /*
1063 * Resume from a power safe. The BIOS already restored
1064 * the TPM state.
1065 */
1066 int tpm_pm_resume(struct device *dev)
1067 {
1068 struct tpm_chip *chip = dev_get_drvdata(dev);
1069
1070 if (chip == NULL)
1071 return -ENODEV;
1072
1073 return 0;
1074 }
1075 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1076
1077 #define TPM_GETRANDOM_RESULT_SIZE 18
1078 static const struct tpm_input_header tpm_getrandom_header = {
1079 .tag = TPM_TAG_RQU_COMMAND,
1080 .length = cpu_to_be32(14),
1081 .ordinal = TPM_ORD_GET_RANDOM
1082 };
1083
1084 /**
1085 * tpm_get_random() - Get random bytes from the tpm's RNG
1086 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1087 * @out: destination buffer for the random bytes
1088 * @max: the max number of bytes to write to @out
1089 *
1090 * Returns < 0 on error and the number of bytes read on success
1091 */
1092 int tpm_get_random(u32 chip_num, u8 *out, size_t max)
1093 {
1094 struct tpm_chip *chip;
1095 struct tpm_cmd_t tpm_cmd;
1096 u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA), rlength;
1097 int err, total = 0, retries = 5;
1098 u8 *dest = out;
1099
1100 if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
1101 return -EINVAL;
1102
1103 chip = tpm_chip_find_get(chip_num);
1104 if (chip == NULL)
1105 return -ENODEV;
1106
1107 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
1108 err = tpm2_get_random(chip, out, max);
1109 tpm_put_ops(chip);
1110 return err;
1111 }
1112
1113 do {
1114 tpm_cmd.header.in = tpm_getrandom_header;
1115 tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
1116
1117 err = tpm_transmit_cmd(chip, &tpm_cmd,
1118 TPM_GETRANDOM_RESULT_SIZE + num_bytes,
1119 offsetof(struct tpm_getrandom_out,
1120 rng_data),
1121 0, "attempting get random");
1122 if (err)
1123 break;
1124
1125 recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
1126
1127 rlength = be32_to_cpu(tpm_cmd.header.out.length);
1128 if (rlength < offsetof(struct tpm_getrandom_out, rng_data) +
1129 recd) {
1130 total = -EFAULT;
1131 break;
1132 }
1133 memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
1134
1135 dest += recd;
1136 total += recd;
1137 num_bytes -= recd;
1138 } while (retries-- && total < max);
1139
1140 tpm_put_ops(chip);
1141 return total ? total : -EIO;
1142 }
1143 EXPORT_SYMBOL_GPL(tpm_get_random);
1144
1145 /**
1146 * tpm_seal_trusted() - seal a trusted key
1147 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1148 * @options: authentication values and other options
1149 * @payload: the key data in clear and encrypted form
1150 *
1151 * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips
1152 * are supported.
1153 */
1154 int tpm_seal_trusted(u32 chip_num, struct trusted_key_payload *payload,
1155 struct trusted_key_options *options)
1156 {
1157 struct tpm_chip *chip;
1158 int rc;
1159
1160 chip = tpm_chip_find_get(chip_num);
1161 if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1162 return -ENODEV;
1163
1164 rc = tpm2_seal_trusted(chip, payload, options);
1165
1166 tpm_put_ops(chip);
1167 return rc;
1168 }
1169 EXPORT_SYMBOL_GPL(tpm_seal_trusted);
1170
1171 /**
1172 * tpm_unseal_trusted() - unseal a trusted key
1173 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1174 * @options: authentication values and other options
1175 * @payload: the key data in clear and encrypted form
1176 *
1177 * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips
1178 * are supported.
1179 */
1180 int tpm_unseal_trusted(u32 chip_num, struct trusted_key_payload *payload,
1181 struct trusted_key_options *options)
1182 {
1183 struct tpm_chip *chip;
1184 int rc;
1185
1186 chip = tpm_chip_find_get(chip_num);
1187 if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1188 return -ENODEV;
1189
1190 rc = tpm2_unseal_trusted(chip, payload, options);
1191
1192 tpm_put_ops(chip);
1193
1194 return rc;
1195 }
1196 EXPORT_SYMBOL_GPL(tpm_unseal_trusted);
1197
1198 static int __init tpm_init(void)
1199 {
1200 int rc;
1201
1202 tpm_class = class_create(THIS_MODULE, "tpm");
1203 if (IS_ERR(tpm_class)) {
1204 pr_err("couldn't create tpm class\n");
1205 return PTR_ERR(tpm_class);
1206 }
1207
1208 rc = alloc_chrdev_region(&tpm_devt, 0, TPM_NUM_DEVICES, "tpm");
1209 if (rc < 0) {
1210 pr_err("tpm: failed to allocate char dev region\n");
1211 class_destroy(tpm_class);
1212 return rc;
1213 }
1214
1215 return 0;
1216 }
1217
1218 static void __exit tpm_exit(void)
1219 {
1220 idr_destroy(&dev_nums_idr);
1221 class_destroy(tpm_class);
1222 unregister_chrdev_region(tpm_devt, TPM_NUM_DEVICES);
1223 }
1224
1225 subsys_initcall(tpm_init);
1226 module_exit(tpm_exit);
1227
1228 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1229 MODULE_DESCRIPTION("TPM Driver");
1230 MODULE_VERSION("2.0");
1231 MODULE_LICENSE("GPL");
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