xref: /openbmc/linux/drivers/char/tpm/tpm-interface.c (revision d236d361)
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 static bool tpm_validate_command(struct tpm_chip *chip,
332 				 struct tpm_space *space,
333 				 const u8 *cmd,
334 				 size_t len)
335 {
336 	const struct tpm_input_header *header = (const void *)cmd;
337 	int i;
338 	u32 cc;
339 	u32 attrs;
340 	unsigned int nr_handles;
341 
342 	if (len < TPM_HEADER_SIZE)
343 		return false;
344 
345 	if (!space)
346 		return true;
347 
348 	if (chip->flags & TPM_CHIP_FLAG_TPM2 && chip->nr_commands) {
349 		cc = be32_to_cpu(header->ordinal);
350 
351 		i = tpm2_find_cc(chip, cc);
352 		if (i < 0) {
353 			dev_dbg(&chip->dev, "0x%04X is an invalid command\n",
354 				cc);
355 			return false;
356 		}
357 
358 		attrs = chip->cc_attrs_tbl[i];
359 		nr_handles =
360 			4 * ((attrs >> TPM2_CC_ATTR_CHANDLES) & GENMASK(2, 0));
361 		if (len < TPM_HEADER_SIZE + 4 * nr_handles)
362 			goto err_len;
363 	}
364 
365 	return true;
366 err_len:
367 	dev_dbg(&chip->dev,
368 		"%s: insufficient command length %zu", __func__, len);
369 	return false;
370 }
371 
372 /**
373  * tmp_transmit - Internal kernel interface to transmit TPM commands.
374  *
375  * @chip: TPM chip to use
376  * @buf: TPM command buffer
377  * @bufsiz: length of the TPM command buffer
378  * @flags: tpm transmit flags - bitmap
379  *
380  * Return:
381  *     0 when the operation is successful.
382  *     A negative number for system errors (errno).
383  */
384 ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
385 		     u8 *buf, size_t bufsiz, unsigned int flags)
386 {
387 	struct tpm_output_header *header = (void *)buf;
388 	int rc;
389 	ssize_t len = 0;
390 	u32 count, ordinal;
391 	unsigned long stop;
392 	bool need_locality;
393 
394 	if (!tpm_validate_command(chip, space, buf, bufsiz))
395 		return -EINVAL;
396 
397 	if (bufsiz > TPM_BUFSIZE)
398 		bufsiz = TPM_BUFSIZE;
399 
400 	count = be32_to_cpu(*((__be32 *) (buf + 2)));
401 	ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
402 	if (count == 0)
403 		return -ENODATA;
404 	if (count > bufsiz) {
405 		dev_err(&chip->dev,
406 			"invalid count value %x %zx\n", count, bufsiz);
407 		return -E2BIG;
408 	}
409 
410 	if (!(flags & TPM_TRANSMIT_UNLOCKED))
411 		mutex_lock(&chip->tpm_mutex);
412 
413 	if (chip->dev.parent)
414 		pm_runtime_get_sync(chip->dev.parent);
415 
416 	/* Store the decision as chip->locality will be changed. */
417 	need_locality = chip->locality == -1;
418 
419 	if (need_locality && chip->ops->request_locality)  {
420 		rc = chip->ops->request_locality(chip, 0);
421 		if (rc < 0)
422 			goto out_no_locality;
423 		chip->locality = rc;
424 	}
425 
426 	rc = tpm2_prepare_space(chip, space, ordinal, buf);
427 	if (rc)
428 		goto out;
429 
430 	rc = chip->ops->send(chip, (u8 *) buf, count);
431 	if (rc < 0) {
432 		dev_err(&chip->dev,
433 			"tpm_transmit: tpm_send: error %d\n", rc);
434 		goto out;
435 	}
436 
437 	if (chip->flags & TPM_CHIP_FLAG_IRQ)
438 		goto out_recv;
439 
440 	if (chip->flags & TPM_CHIP_FLAG_TPM2)
441 		stop = jiffies + tpm2_calc_ordinal_duration(chip, ordinal);
442 	else
443 		stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
444 	do {
445 		u8 status = chip->ops->status(chip);
446 		if ((status & chip->ops->req_complete_mask) ==
447 		    chip->ops->req_complete_val)
448 			goto out_recv;
449 
450 		if (chip->ops->req_canceled(chip, status)) {
451 			dev_err(&chip->dev, "Operation Canceled\n");
452 			rc = -ECANCELED;
453 			goto out;
454 		}
455 
456 		msleep(TPM_TIMEOUT);	/* CHECK */
457 		rmb();
458 	} while (time_before(jiffies, stop));
459 
460 	chip->ops->cancel(chip);
461 	dev_err(&chip->dev, "Operation Timed out\n");
462 	rc = -ETIME;
463 	goto out;
464 
465 out_recv:
466 	len = chip->ops->recv(chip, (u8 *) buf, bufsiz);
467 	if (len < 0) {
468 		rc = len;
469 		dev_err(&chip->dev,
470 			"tpm_transmit: tpm_recv: error %d\n", rc);
471 		goto out;
472 	} else if (len < TPM_HEADER_SIZE) {
473 		rc = -EFAULT;
474 		goto out;
475 	}
476 
477 	if (len != be32_to_cpu(header->length)) {
478 		rc = -EFAULT;
479 		goto out;
480 	}
481 
482 	rc = tpm2_commit_space(chip, space, ordinal, buf, &len);
483 
484 out:
485 	if (need_locality && chip->ops->relinquish_locality) {
486 		chip->ops->relinquish_locality(chip, chip->locality);
487 		chip->locality = -1;
488 	}
489 out_no_locality:
490 	if (chip->dev.parent)
491 		pm_runtime_put_sync(chip->dev.parent);
492 
493 	if (!(flags & TPM_TRANSMIT_UNLOCKED))
494 		mutex_unlock(&chip->tpm_mutex);
495 	return rc ? rc : len;
496 }
497 
498 /**
499  * tmp_transmit_cmd - send a tpm command to the device
500  *    The function extracts tpm out header return code
501  *
502  * @chip: TPM chip to use
503  * @buf: TPM command buffer
504  * @bufsiz: length of the buffer
505  * @min_rsp_body_length: minimum expected length of response body
506  * @flags: tpm transmit flags - bitmap
507  * @desc: command description used in the error message
508  *
509  * Return:
510  *     0 when the operation is successful.
511  *     A negative number for system errors (errno).
512  *     A positive number for a TPM error.
513  */
514 ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_space *space,
515 			 const void *buf, size_t bufsiz,
516 			 size_t min_rsp_body_length, unsigned int flags,
517 			 const char *desc)
518 {
519 	const struct tpm_output_header *header = buf;
520 	int err;
521 	ssize_t len;
522 
523 	len = tpm_transmit(chip, space, (u8 *)buf, bufsiz, flags);
524 	if (len <  0)
525 		return len;
526 
527 	err = be32_to_cpu(header->return_code);
528 	if (err != 0 && desc)
529 		dev_err(&chip->dev, "A TPM error (%d) occurred %s\n", err,
530 			desc);
531 	if (err)
532 		return err;
533 
534 	if (len < min_rsp_body_length + TPM_HEADER_SIZE)
535 		return -EFAULT;
536 
537 	return 0;
538 }
539 
540 #define TPM_DIGEST_SIZE 20
541 #define TPM_RET_CODE_IDX 6
542 #define TPM_INTERNAL_RESULT_SIZE 200
543 #define TPM_ORD_GET_CAP cpu_to_be32(101)
544 #define TPM_ORD_GET_RANDOM cpu_to_be32(70)
545 
546 static const struct tpm_input_header tpm_getcap_header = {
547 	.tag = TPM_TAG_RQU_COMMAND,
548 	.length = cpu_to_be32(22),
549 	.ordinal = TPM_ORD_GET_CAP
550 };
551 
552 ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
553 		   const char *desc, size_t min_cap_length)
554 {
555 	struct tpm_cmd_t tpm_cmd;
556 	int rc;
557 
558 	tpm_cmd.header.in = tpm_getcap_header;
559 	if (subcap_id == TPM_CAP_VERSION_1_1 ||
560 	    subcap_id == TPM_CAP_VERSION_1_2) {
561 		tpm_cmd.params.getcap_in.cap = cpu_to_be32(subcap_id);
562 		/*subcap field not necessary */
563 		tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
564 		tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
565 	} else {
566 		if (subcap_id == TPM_CAP_FLAG_PERM ||
567 		    subcap_id == TPM_CAP_FLAG_VOL)
568 			tpm_cmd.params.getcap_in.cap =
569 				cpu_to_be32(TPM_CAP_FLAG);
570 		else
571 			tpm_cmd.params.getcap_in.cap =
572 				cpu_to_be32(TPM_CAP_PROP);
573 		tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
574 		tpm_cmd.params.getcap_in.subcap = cpu_to_be32(subcap_id);
575 	}
576 	rc = tpm_transmit_cmd(chip, NULL, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
577 			      min_cap_length, 0, desc);
578 	if (!rc)
579 		*cap = tpm_cmd.params.getcap_out.cap;
580 	return rc;
581 }
582 EXPORT_SYMBOL_GPL(tpm_getcap);
583 
584 #define TPM_ORD_STARTUP cpu_to_be32(153)
585 #define TPM_ST_CLEAR cpu_to_be16(1)
586 #define TPM_ST_STATE cpu_to_be16(2)
587 #define TPM_ST_DEACTIVATED cpu_to_be16(3)
588 static const struct tpm_input_header tpm_startup_header = {
589 	.tag = TPM_TAG_RQU_COMMAND,
590 	.length = cpu_to_be32(12),
591 	.ordinal = TPM_ORD_STARTUP
592 };
593 
594 static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
595 {
596 	struct tpm_cmd_t start_cmd;
597 	start_cmd.header.in = tpm_startup_header;
598 
599 	start_cmd.params.startup_in.startup_type = startup_type;
600 	return tpm_transmit_cmd(chip, NULL, &start_cmd,
601 				TPM_INTERNAL_RESULT_SIZE, 0,
602 				0, "attempting to start the TPM");
603 }
604 
605 int tpm_get_timeouts(struct tpm_chip *chip)
606 {
607 	cap_t cap;
608 	unsigned long timeout_old[4], timeout_chip[4], timeout_eff[4];
609 	ssize_t rc;
610 
611 	if (chip->flags & TPM_CHIP_FLAG_HAVE_TIMEOUTS)
612 		return 0;
613 
614 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
615 		/* Fixed timeouts for TPM2 */
616 		chip->timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
617 		chip->timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
618 		chip->timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
619 		chip->timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
620 		chip->duration[TPM_SHORT] =
621 		    msecs_to_jiffies(TPM2_DURATION_SHORT);
622 		chip->duration[TPM_MEDIUM] =
623 		    msecs_to_jiffies(TPM2_DURATION_MEDIUM);
624 		chip->duration[TPM_LONG] =
625 		    msecs_to_jiffies(TPM2_DURATION_LONG);
626 
627 		chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
628 		return 0;
629 	}
630 
631 	rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, NULL,
632 			sizeof(cap.timeout));
633 	if (rc == TPM_ERR_INVALID_POSTINIT) {
634 		/* The TPM is not started, we are the first to talk to it.
635 		   Execute a startup command. */
636 		dev_info(&chip->dev, "Issuing TPM_STARTUP\n");
637 		if (tpm_startup(chip, TPM_ST_CLEAR))
638 			return rc;
639 
640 		rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
641 				"attempting to determine the timeouts",
642 				sizeof(cap.timeout));
643 	}
644 
645 	if (rc) {
646 		dev_err(&chip->dev,
647 			"A TPM error (%zd) occurred attempting to determine the timeouts\n",
648 			rc);
649 		return rc;
650 	}
651 
652 	timeout_old[0] = jiffies_to_usecs(chip->timeout_a);
653 	timeout_old[1] = jiffies_to_usecs(chip->timeout_b);
654 	timeout_old[2] = jiffies_to_usecs(chip->timeout_c);
655 	timeout_old[3] = jiffies_to_usecs(chip->timeout_d);
656 	timeout_chip[0] = be32_to_cpu(cap.timeout.a);
657 	timeout_chip[1] = be32_to_cpu(cap.timeout.b);
658 	timeout_chip[2] = be32_to_cpu(cap.timeout.c);
659 	timeout_chip[3] = be32_to_cpu(cap.timeout.d);
660 	memcpy(timeout_eff, timeout_chip, sizeof(timeout_eff));
661 
662 	/*
663 	 * Provide ability for vendor overrides of timeout values in case
664 	 * of misreporting.
665 	 */
666 	if (chip->ops->update_timeouts != NULL)
667 		chip->timeout_adjusted =
668 			chip->ops->update_timeouts(chip, timeout_eff);
669 
670 	if (!chip->timeout_adjusted) {
671 		/* Restore default if chip reported 0 */
672 		int i;
673 
674 		for (i = 0; i < ARRAY_SIZE(timeout_eff); i++) {
675 			if (timeout_eff[i])
676 				continue;
677 
678 			timeout_eff[i] = timeout_old[i];
679 			chip->timeout_adjusted = true;
680 		}
681 
682 		if (timeout_eff[0] != 0 && timeout_eff[0] < 1000) {
683 			/* timeouts in msec rather usec */
684 			for (i = 0; i != ARRAY_SIZE(timeout_eff); i++)
685 				timeout_eff[i] *= 1000;
686 			chip->timeout_adjusted = true;
687 		}
688 	}
689 
690 	/* Report adjusted timeouts */
691 	if (chip->timeout_adjusted) {
692 		dev_info(&chip->dev,
693 			 HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n",
694 			 timeout_chip[0], timeout_eff[0],
695 			 timeout_chip[1], timeout_eff[1],
696 			 timeout_chip[2], timeout_eff[2],
697 			 timeout_chip[3], timeout_eff[3]);
698 	}
699 
700 	chip->timeout_a = usecs_to_jiffies(timeout_eff[0]);
701 	chip->timeout_b = usecs_to_jiffies(timeout_eff[1]);
702 	chip->timeout_c = usecs_to_jiffies(timeout_eff[2]);
703 	chip->timeout_d = usecs_to_jiffies(timeout_eff[3]);
704 
705 	rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap,
706 			"attempting to determine the durations",
707 			sizeof(cap.duration));
708 	if (rc)
709 		return rc;
710 
711 	chip->duration[TPM_SHORT] =
712 		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short));
713 	chip->duration[TPM_MEDIUM] =
714 		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium));
715 	chip->duration[TPM_LONG] =
716 		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long));
717 
718 	/* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
719 	 * value wrong and apparently reports msecs rather than usecs. So we
720 	 * fix up the resulting too-small TPM_SHORT value to make things work.
721 	 * We also scale the TPM_MEDIUM and -_LONG values by 1000.
722 	 */
723 	if (chip->duration[TPM_SHORT] < (HZ / 100)) {
724 		chip->duration[TPM_SHORT] = HZ;
725 		chip->duration[TPM_MEDIUM] *= 1000;
726 		chip->duration[TPM_LONG] *= 1000;
727 		chip->duration_adjusted = true;
728 		dev_info(&chip->dev, "Adjusting TPM timeout parameters.");
729 	}
730 
731 	chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
732 	return 0;
733 }
734 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
735 
736 #define TPM_ORD_CONTINUE_SELFTEST 83
737 #define CONTINUE_SELFTEST_RESULT_SIZE 10
738 
739 static const struct tpm_input_header continue_selftest_header = {
740 	.tag = TPM_TAG_RQU_COMMAND,
741 	.length = cpu_to_be32(10),
742 	.ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
743 };
744 
745 /**
746  * tpm_continue_selftest -- run TPM's selftest
747  * @chip: TPM chip to use
748  *
749  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
750  * a TPM error code.
751  */
752 static int tpm_continue_selftest(struct tpm_chip *chip)
753 {
754 	int rc;
755 	struct tpm_cmd_t cmd;
756 
757 	cmd.header.in = continue_selftest_header;
758 	rc = tpm_transmit_cmd(chip, NULL, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
759 			      0, 0, "continue selftest");
760 	return rc;
761 }
762 
763 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
764 #define READ_PCR_RESULT_SIZE 30
765 #define READ_PCR_RESULT_BODY_SIZE 20
766 static const struct tpm_input_header pcrread_header = {
767 	.tag = TPM_TAG_RQU_COMMAND,
768 	.length = cpu_to_be32(14),
769 	.ordinal = TPM_ORDINAL_PCRREAD
770 };
771 
772 int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
773 {
774 	int rc;
775 	struct tpm_cmd_t cmd;
776 
777 	cmd.header.in = pcrread_header;
778 	cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
779 	rc = tpm_transmit_cmd(chip, NULL, &cmd, READ_PCR_RESULT_SIZE,
780 			      READ_PCR_RESULT_BODY_SIZE, 0,
781 			      "attempting to read a pcr value");
782 
783 	if (rc == 0)
784 		memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
785 		       TPM_DIGEST_SIZE);
786 	return rc;
787 }
788 
789 /**
790  * tpm_is_tpm2 - is the chip a TPM2 chip?
791  * @chip_num:	tpm idx # or ANY
792  *
793  * Returns < 0 on error, and 1 or 0 on success depending whether the chip
794  * is a TPM2 chip.
795  */
796 int tpm_is_tpm2(u32 chip_num)
797 {
798 	struct tpm_chip *chip;
799 	int rc;
800 
801 	chip = tpm_chip_find_get(chip_num);
802 	if (chip == NULL)
803 		return -ENODEV;
804 
805 	rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0;
806 
807 	tpm_put_ops(chip);
808 
809 	return rc;
810 }
811 EXPORT_SYMBOL_GPL(tpm_is_tpm2);
812 
813 /**
814  * tpm_pcr_read - read a pcr value
815  * @chip_num:	tpm idx # or ANY
816  * @pcr_idx:	pcr idx to retrieve
817  * @res_buf:	TPM_PCR value
818  *		size of res_buf is 20 bytes (or NULL if you don't care)
819  *
820  * The TPM driver should be built-in, but for whatever reason it
821  * isn't, protect against the chip disappearing, by incrementing
822  * the module usage count.
823  */
824 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
825 {
826 	struct tpm_chip *chip;
827 	int rc;
828 
829 	chip = tpm_chip_find_get(chip_num);
830 	if (chip == NULL)
831 		return -ENODEV;
832 	if (chip->flags & TPM_CHIP_FLAG_TPM2)
833 		rc = tpm2_pcr_read(chip, pcr_idx, res_buf);
834 	else
835 		rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf);
836 	tpm_put_ops(chip);
837 	return rc;
838 }
839 EXPORT_SYMBOL_GPL(tpm_pcr_read);
840 
841 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
842 #define EXTEND_PCR_RESULT_SIZE 34
843 #define EXTEND_PCR_RESULT_BODY_SIZE 20
844 static const struct tpm_input_header pcrextend_header = {
845 	.tag = TPM_TAG_RQU_COMMAND,
846 	.length = cpu_to_be32(34),
847 	.ordinal = TPM_ORD_PCR_EXTEND
848 };
849 
850 /**
851  * tpm_pcr_extend - extend pcr value with hash
852  * @chip_num:	tpm idx # or AN&
853  * @pcr_idx:	pcr idx to extend
854  * @hash:	hash value used to extend pcr value
855  *
856  * The TPM driver should be built-in, but for whatever reason it
857  * isn't, protect against the chip disappearing, by incrementing
858  * the module usage count.
859  */
860 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
861 {
862 	struct tpm_cmd_t cmd;
863 	int rc;
864 	struct tpm_chip *chip;
865 	struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)];
866 	u32 count = 0;
867 	int i;
868 
869 	chip = tpm_chip_find_get(chip_num);
870 	if (chip == NULL)
871 		return -ENODEV;
872 
873 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
874 		memset(digest_list, 0, sizeof(digest_list));
875 
876 		for (i = 0; i < ARRAY_SIZE(chip->active_banks) &&
877 			    chip->active_banks[i] != TPM2_ALG_ERROR; i++) {
878 			digest_list[i].alg_id = chip->active_banks[i];
879 			memcpy(digest_list[i].digest, hash, TPM_DIGEST_SIZE);
880 			count++;
881 		}
882 
883 		rc = tpm2_pcr_extend(chip, pcr_idx, count, digest_list);
884 		tpm_put_ops(chip);
885 		return rc;
886 	}
887 
888 	cmd.header.in = pcrextend_header;
889 	cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
890 	memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
891 	rc = tpm_transmit_cmd(chip, NULL, &cmd, EXTEND_PCR_RESULT_SIZE,
892 			      EXTEND_PCR_RESULT_BODY_SIZE, 0,
893 			      "attempting extend a PCR value");
894 
895 	tpm_put_ops(chip);
896 	return rc;
897 }
898 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
899 
900 /**
901  * tpm_do_selftest - have the TPM continue its selftest and wait until it
902  *                   can receive further commands
903  * @chip: TPM chip to use
904  *
905  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
906  * a TPM error code.
907  */
908 int tpm_do_selftest(struct tpm_chip *chip)
909 {
910 	int rc;
911 	unsigned int loops;
912 	unsigned int delay_msec = 100;
913 	unsigned long duration;
914 	u8 dummy[TPM_DIGEST_SIZE];
915 
916 	duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST);
917 
918 	loops = jiffies_to_msecs(duration) / delay_msec;
919 
920 	rc = tpm_continue_selftest(chip);
921 	/* This may fail if there was no TPM driver during a suspend/resume
922 	 * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
923 	 */
924 	if (rc)
925 		return rc;
926 
927 	do {
928 		/* Attempt to read a PCR value */
929 		rc = tpm_pcr_read_dev(chip, 0, dummy);
930 
931 		/* Some buggy TPMs will not respond to tpm_tis_ready() for
932 		 * around 300ms while the self test is ongoing, keep trying
933 		 * until the self test duration expires. */
934 		if (rc == -ETIME) {
935 			dev_info(
936 			    &chip->dev, HW_ERR
937 			    "TPM command timed out during continue self test");
938 			msleep(delay_msec);
939 			continue;
940 		}
941 
942 		if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
943 			dev_info(&chip->dev,
944 				 "TPM is disabled/deactivated (0x%X)\n", rc);
945 			/* TPM is disabled and/or deactivated; driver can
946 			 * proceed and TPM does handle commands for
947 			 * suspend/resume correctly
948 			 */
949 			return 0;
950 		}
951 		if (rc != TPM_WARN_DOING_SELFTEST)
952 			return rc;
953 		msleep(delay_msec);
954 	} while (--loops > 0);
955 
956 	return rc;
957 }
958 EXPORT_SYMBOL_GPL(tpm_do_selftest);
959 
960 /**
961  * tpm1_auto_startup - Perform the standard automatic TPM initialization
962  *                     sequence
963  * @chip: TPM chip to use
964  *
965  * Returns 0 on success, < 0 in case of fatal error.
966  */
967 int tpm1_auto_startup(struct tpm_chip *chip)
968 {
969 	int rc;
970 
971 	rc = tpm_get_timeouts(chip);
972 	if (rc)
973 		goto out;
974 	rc = tpm_do_selftest(chip);
975 	if (rc) {
976 		dev_err(&chip->dev, "TPM self test failed\n");
977 		goto out;
978 	}
979 
980 	return rc;
981 out:
982 	if (rc > 0)
983 		rc = -ENODEV;
984 	return rc;
985 }
986 
987 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
988 {
989 	struct tpm_chip *chip;
990 	int rc;
991 
992 	chip = tpm_chip_find_get(chip_num);
993 	if (chip == NULL)
994 		return -ENODEV;
995 
996 	rc = tpm_transmit_cmd(chip, NULL, cmd, buflen, 0, 0,
997 			      "attempting tpm_cmd");
998 	tpm_put_ops(chip);
999 	return rc;
1000 }
1001 EXPORT_SYMBOL_GPL(tpm_send);
1002 
1003 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
1004 					bool check_cancel, bool *canceled)
1005 {
1006 	u8 status = chip->ops->status(chip);
1007 
1008 	*canceled = false;
1009 	if ((status & mask) == mask)
1010 		return true;
1011 	if (check_cancel && chip->ops->req_canceled(chip, status)) {
1012 		*canceled = true;
1013 		return true;
1014 	}
1015 	return false;
1016 }
1017 
1018 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
1019 		      wait_queue_head_t *queue, bool check_cancel)
1020 {
1021 	unsigned long stop;
1022 	long rc;
1023 	u8 status;
1024 	bool canceled = false;
1025 
1026 	/* check current status */
1027 	status = chip->ops->status(chip);
1028 	if ((status & mask) == mask)
1029 		return 0;
1030 
1031 	stop = jiffies + timeout;
1032 
1033 	if (chip->flags & TPM_CHIP_FLAG_IRQ) {
1034 again:
1035 		timeout = stop - jiffies;
1036 		if ((long)timeout <= 0)
1037 			return -ETIME;
1038 		rc = wait_event_interruptible_timeout(*queue,
1039 			wait_for_tpm_stat_cond(chip, mask, check_cancel,
1040 					       &canceled),
1041 			timeout);
1042 		if (rc > 0) {
1043 			if (canceled)
1044 				return -ECANCELED;
1045 			return 0;
1046 		}
1047 		if (rc == -ERESTARTSYS && freezing(current)) {
1048 			clear_thread_flag(TIF_SIGPENDING);
1049 			goto again;
1050 		}
1051 	} else {
1052 		do {
1053 			msleep(TPM_TIMEOUT);
1054 			status = chip->ops->status(chip);
1055 			if ((status & mask) == mask)
1056 				return 0;
1057 		} while (time_before(jiffies, stop));
1058 	}
1059 	return -ETIME;
1060 }
1061 EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
1062 
1063 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1064 #define SAVESTATE_RESULT_SIZE 10
1065 
1066 static const struct tpm_input_header savestate_header = {
1067 	.tag = TPM_TAG_RQU_COMMAND,
1068 	.length = cpu_to_be32(10),
1069 	.ordinal = TPM_ORD_SAVESTATE
1070 };
1071 
1072 /*
1073  * We are about to suspend. Save the TPM state
1074  * so that it can be restored.
1075  */
1076 int tpm_pm_suspend(struct device *dev)
1077 {
1078 	struct tpm_chip *chip = dev_get_drvdata(dev);
1079 	struct tpm_cmd_t cmd;
1080 	int rc, try;
1081 
1082 	u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1083 
1084 	if (chip == NULL)
1085 		return -ENODEV;
1086 
1087 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
1088 		tpm2_shutdown(chip, TPM2_SU_STATE);
1089 		return 0;
1090 	}
1091 
1092 	/* for buggy tpm, flush pcrs with extend to selected dummy */
1093 	if (tpm_suspend_pcr) {
1094 		cmd.header.in = pcrextend_header;
1095 		cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1096 		memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1097 		       TPM_DIGEST_SIZE);
1098 		rc = tpm_transmit_cmd(chip, NULL, &cmd, EXTEND_PCR_RESULT_SIZE,
1099 				      EXTEND_PCR_RESULT_BODY_SIZE, 0,
1100 				      "extending dummy pcr before suspend");
1101 	}
1102 
1103 	/* now do the actual savestate */
1104 	for (try = 0; try < TPM_RETRY; try++) {
1105 		cmd.header.in = savestate_header;
1106 		rc = tpm_transmit_cmd(chip, NULL, &cmd, SAVESTATE_RESULT_SIZE,
1107 				      0, 0, NULL);
1108 
1109 		/*
1110 		 * If the TPM indicates that it is too busy to respond to
1111 		 * this command then retry before giving up.  It can take
1112 		 * several seconds for this TPM to be ready.
1113 		 *
1114 		 * This can happen if the TPM has already been sent the
1115 		 * SaveState command before the driver has loaded.  TCG 1.2
1116 		 * specification states that any communication after SaveState
1117 		 * may cause the TPM to invalidate previously saved state.
1118 		 */
1119 		if (rc != TPM_WARN_RETRY)
1120 			break;
1121 		msleep(TPM_TIMEOUT_RETRY);
1122 	}
1123 
1124 	if (rc)
1125 		dev_err(&chip->dev,
1126 			"Error (%d) sending savestate before suspend\n", rc);
1127 	else if (try > 0)
1128 		dev_warn(&chip->dev, "TPM savestate took %dms\n",
1129 			 try * TPM_TIMEOUT_RETRY);
1130 
1131 	return rc;
1132 }
1133 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1134 
1135 /*
1136  * Resume from a power safe. The BIOS already restored
1137  * the TPM state.
1138  */
1139 int tpm_pm_resume(struct device *dev)
1140 {
1141 	struct tpm_chip *chip = dev_get_drvdata(dev);
1142 
1143 	if (chip == NULL)
1144 		return -ENODEV;
1145 
1146 	return 0;
1147 }
1148 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1149 
1150 #define TPM_GETRANDOM_RESULT_SIZE	18
1151 static const struct tpm_input_header tpm_getrandom_header = {
1152 	.tag = TPM_TAG_RQU_COMMAND,
1153 	.length = cpu_to_be32(14),
1154 	.ordinal = TPM_ORD_GET_RANDOM
1155 };
1156 
1157 /**
1158  * tpm_get_random() - Get random bytes from the tpm's RNG
1159  * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1160  * @out: destination buffer for the random bytes
1161  * @max: the max number of bytes to write to @out
1162  *
1163  * Returns < 0 on error and the number of bytes read on success
1164  */
1165 int tpm_get_random(u32 chip_num, u8 *out, size_t max)
1166 {
1167 	struct tpm_chip *chip;
1168 	struct tpm_cmd_t tpm_cmd;
1169 	u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA), rlength;
1170 	int err, total = 0, retries = 5;
1171 	u8 *dest = out;
1172 
1173 	if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
1174 		return -EINVAL;
1175 
1176 	chip = tpm_chip_find_get(chip_num);
1177 	if (chip == NULL)
1178 		return -ENODEV;
1179 
1180 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
1181 		err = tpm2_get_random(chip, out, max);
1182 		tpm_put_ops(chip);
1183 		return err;
1184 	}
1185 
1186 	do {
1187 		tpm_cmd.header.in = tpm_getrandom_header;
1188 		tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
1189 
1190 		err = tpm_transmit_cmd(chip, NULL, &tpm_cmd,
1191 				       TPM_GETRANDOM_RESULT_SIZE + num_bytes,
1192 				       offsetof(struct tpm_getrandom_out,
1193 						rng_data),
1194 				       0, "attempting get random");
1195 		if (err)
1196 			break;
1197 
1198 		recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
1199 
1200 		rlength = be32_to_cpu(tpm_cmd.header.out.length);
1201 		if (rlength < offsetof(struct tpm_getrandom_out, rng_data) +
1202 			      recd) {
1203 			total = -EFAULT;
1204 			break;
1205 		}
1206 		memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
1207 
1208 		dest += recd;
1209 		total += recd;
1210 		num_bytes -= recd;
1211 	} while (retries-- && total < max);
1212 
1213 	tpm_put_ops(chip);
1214 	return total ? total : -EIO;
1215 }
1216 EXPORT_SYMBOL_GPL(tpm_get_random);
1217 
1218 /**
1219  * tpm_seal_trusted() - seal a trusted key
1220  * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1221  * @options: authentication values and other options
1222  * @payload: the key data in clear and encrypted form
1223  *
1224  * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips
1225  * are supported.
1226  */
1227 int tpm_seal_trusted(u32 chip_num, struct trusted_key_payload *payload,
1228 		     struct trusted_key_options *options)
1229 {
1230 	struct tpm_chip *chip;
1231 	int rc;
1232 
1233 	chip = tpm_chip_find_get(chip_num);
1234 	if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1235 		return -ENODEV;
1236 
1237 	rc = tpm2_seal_trusted(chip, payload, options);
1238 
1239 	tpm_put_ops(chip);
1240 	return rc;
1241 }
1242 EXPORT_SYMBOL_GPL(tpm_seal_trusted);
1243 
1244 /**
1245  * tpm_unseal_trusted() - unseal a trusted key
1246  * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1247  * @options: authentication values and other options
1248  * @payload: the key data in clear and encrypted form
1249  *
1250  * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips
1251  * are supported.
1252  */
1253 int tpm_unseal_trusted(u32 chip_num, struct trusted_key_payload *payload,
1254 		       struct trusted_key_options *options)
1255 {
1256 	struct tpm_chip *chip;
1257 	int rc;
1258 
1259 	chip = tpm_chip_find_get(chip_num);
1260 	if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1261 		return -ENODEV;
1262 
1263 	rc = tpm2_unseal_trusted(chip, payload, options);
1264 
1265 	tpm_put_ops(chip);
1266 
1267 	return rc;
1268 }
1269 EXPORT_SYMBOL_GPL(tpm_unseal_trusted);
1270 
1271 static int __init tpm_init(void)
1272 {
1273 	int rc;
1274 
1275 	tpm_class = class_create(THIS_MODULE, "tpm");
1276 	if (IS_ERR(tpm_class)) {
1277 		pr_err("couldn't create tpm class\n");
1278 		return PTR_ERR(tpm_class);
1279 	}
1280 
1281 	tpmrm_class = class_create(THIS_MODULE, "tpmrm");
1282 	if (IS_ERR(tpmrm_class)) {
1283 		pr_err("couldn't create tpmrm class\n");
1284 		class_destroy(tpm_class);
1285 		return PTR_ERR(tpmrm_class);
1286 	}
1287 
1288 	rc = alloc_chrdev_region(&tpm_devt, 0, 2*TPM_NUM_DEVICES, "tpm");
1289 	if (rc < 0) {
1290 		pr_err("tpm: failed to allocate char dev region\n");
1291 		class_destroy(tpmrm_class);
1292 		class_destroy(tpm_class);
1293 		return rc;
1294 	}
1295 
1296 	return 0;
1297 }
1298 
1299 static void __exit tpm_exit(void)
1300 {
1301 	idr_destroy(&dev_nums_idr);
1302 	class_destroy(tpm_class);
1303 	class_destroy(tpmrm_class);
1304 	unregister_chrdev_region(tpm_devt, 2*TPM_NUM_DEVICES);
1305 }
1306 
1307 subsys_initcall(tpm_init);
1308 module_exit(tpm_exit);
1309 
1310 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1311 MODULE_DESCRIPTION("TPM Driver");
1312 MODULE_VERSION("2.0");
1313 MODULE_LICENSE("GPL");
1314