xref: /openbmc/linux/drivers/char/tpm/tpm-interface.c (revision be4c9acfe2976b6e024d15656254d2eb207b83a8)
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 (!(flags & TPM_TRANSMIT_RAW) &&
420 	    need_locality && chip->ops->request_locality)  {
421 		rc = chip->ops->request_locality(chip, 0);
422 		if (rc < 0)
423 			goto out_no_locality;
424 		chip->locality = rc;
425 	}
426 
427 	rc = tpm2_prepare_space(chip, space, ordinal, buf);
428 	if (rc)
429 		goto out;
430 
431 	rc = chip->ops->send(chip, (u8 *) buf, count);
432 	if (rc < 0) {
433 		if (rc != -EPIPE)
434 			dev_err(&chip->dev,
435 				"%s: tpm_send: error %d\n", __func__, rc);
436 		goto out;
437 	}
438 
439 	if (chip->flags & TPM_CHIP_FLAG_IRQ)
440 		goto out_recv;
441 
442 	if (chip->flags & TPM_CHIP_FLAG_TPM2)
443 		stop = jiffies + tpm2_calc_ordinal_duration(chip, ordinal);
444 	else
445 		stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
446 	do {
447 		u8 status = chip->ops->status(chip);
448 		if ((status & chip->ops->req_complete_mask) ==
449 		    chip->ops->req_complete_val)
450 			goto out_recv;
451 
452 		if (chip->ops->req_canceled(chip, status)) {
453 			dev_err(&chip->dev, "Operation Canceled\n");
454 			rc = -ECANCELED;
455 			goto out;
456 		}
457 
458 		msleep(TPM_TIMEOUT);	/* CHECK */
459 		rmb();
460 	} while (time_before(jiffies, stop));
461 
462 	chip->ops->cancel(chip);
463 	dev_err(&chip->dev, "Operation Timed out\n");
464 	rc = -ETIME;
465 	goto out;
466 
467 out_recv:
468 	len = chip->ops->recv(chip, (u8 *) buf, bufsiz);
469 	if (len < 0) {
470 		rc = len;
471 		dev_err(&chip->dev,
472 			"tpm_transmit: tpm_recv: error %d\n", rc);
473 		goto out;
474 	} else if (len < TPM_HEADER_SIZE) {
475 		rc = -EFAULT;
476 		goto out;
477 	}
478 
479 	if (len != be32_to_cpu(header->length)) {
480 		rc = -EFAULT;
481 		goto out;
482 	}
483 
484 	rc = tpm2_commit_space(chip, space, ordinal, buf, &len);
485 
486 out:
487 	if (need_locality && chip->ops->relinquish_locality) {
488 		chip->ops->relinquish_locality(chip, chip->locality);
489 		chip->locality = -1;
490 	}
491 out_no_locality:
492 	if (chip->dev.parent)
493 		pm_runtime_put_sync(chip->dev.parent);
494 
495 	if (!(flags & TPM_TRANSMIT_UNLOCKED))
496 		mutex_unlock(&chip->tpm_mutex);
497 	return rc ? rc : len;
498 }
499 
500 /**
501  * tmp_transmit_cmd - send a tpm command to the device
502  *    The function extracts tpm out header return code
503  *
504  * @chip: TPM chip to use
505  * @buf: TPM command buffer
506  * @bufsiz: length of the buffer
507  * @min_rsp_body_length: minimum expected length of response body
508  * @flags: tpm transmit flags - bitmap
509  * @desc: command description used in the error message
510  *
511  * Return:
512  *     0 when the operation is successful.
513  *     A negative number for system errors (errno).
514  *     A positive number for a TPM error.
515  */
516 ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_space *space,
517 			 const void *buf, size_t bufsiz,
518 			 size_t min_rsp_body_length, unsigned int flags,
519 			 const char *desc)
520 {
521 	const struct tpm_output_header *header = buf;
522 	int err;
523 	ssize_t len;
524 
525 	len = tpm_transmit(chip, space, (u8 *)buf, bufsiz, flags);
526 	if (len <  0)
527 		return len;
528 
529 	err = be32_to_cpu(header->return_code);
530 	if (err != 0 && desc)
531 		dev_err(&chip->dev, "A TPM error (%d) occurred %s\n", err,
532 			desc);
533 	if (err)
534 		return err;
535 
536 	if (len < min_rsp_body_length + TPM_HEADER_SIZE)
537 		return -EFAULT;
538 
539 	return 0;
540 }
541 EXPORT_SYMBOL_GPL(tpm_transmit_cmd);
542 
543 #define TPM_DIGEST_SIZE 20
544 #define TPM_RET_CODE_IDX 6
545 #define TPM_INTERNAL_RESULT_SIZE 200
546 #define TPM_ORD_GET_CAP 101
547 #define TPM_ORD_GET_RANDOM 70
548 
549 static const struct tpm_input_header tpm_getcap_header = {
550 	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
551 	.length = cpu_to_be32(22),
552 	.ordinal = cpu_to_be32(TPM_ORD_GET_CAP)
553 };
554 
555 ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
556 		   const char *desc, size_t min_cap_length)
557 {
558 	struct tpm_buf buf;
559 	int rc;
560 
561 	rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_CAP);
562 	if (rc)
563 		return rc;
564 
565 	if (subcap_id == TPM_CAP_VERSION_1_1 ||
566 	    subcap_id == TPM_CAP_VERSION_1_2) {
567 		tpm_buf_append_u32(&buf, subcap_id);
568 		tpm_buf_append_u32(&buf, 0);
569 	} else {
570 		if (subcap_id == TPM_CAP_FLAG_PERM ||
571 		    subcap_id == TPM_CAP_FLAG_VOL)
572 			tpm_buf_append_u32(&buf, TPM_CAP_FLAG);
573 		else
574 			tpm_buf_append_u32(&buf, TPM_CAP_PROP);
575 
576 		tpm_buf_append_u32(&buf, 4);
577 		tpm_buf_append_u32(&buf, subcap_id);
578 	}
579 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE,
580 			      min_cap_length, 0, desc);
581 	if (!rc)
582 		*cap = *(cap_t *)&buf.data[TPM_HEADER_SIZE + 4];
583 
584 	tpm_buf_destroy(&buf);
585 	return rc;
586 }
587 EXPORT_SYMBOL_GPL(tpm_getcap);
588 
589 #define TPM_ORD_STARTUP 153
590 #define TPM_ST_CLEAR cpu_to_be16(1)
591 #define TPM_ST_STATE cpu_to_be16(2)
592 #define TPM_ST_DEACTIVATED cpu_to_be16(3)
593 static const struct tpm_input_header tpm_startup_header = {
594 	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
595 	.length = cpu_to_be32(12),
596 	.ordinal = cpu_to_be32(TPM_ORD_STARTUP)
597 };
598 
599 static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
600 {
601 	struct tpm_cmd_t start_cmd;
602 	start_cmd.header.in = tpm_startup_header;
603 
604 	start_cmd.params.startup_in.startup_type = startup_type;
605 	return tpm_transmit_cmd(chip, NULL, &start_cmd,
606 				TPM_INTERNAL_RESULT_SIZE, 0,
607 				0, "attempting to start the TPM");
608 }
609 
610 int tpm_get_timeouts(struct tpm_chip *chip)
611 {
612 	cap_t cap;
613 	unsigned long timeout_old[4], timeout_chip[4], timeout_eff[4];
614 	ssize_t rc;
615 
616 	if (chip->flags & TPM_CHIP_FLAG_HAVE_TIMEOUTS)
617 		return 0;
618 
619 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
620 		/* Fixed timeouts for TPM2 */
621 		chip->timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
622 		chip->timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
623 		chip->timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
624 		chip->timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
625 		chip->duration[TPM_SHORT] =
626 		    msecs_to_jiffies(TPM2_DURATION_SHORT);
627 		chip->duration[TPM_MEDIUM] =
628 		    msecs_to_jiffies(TPM2_DURATION_MEDIUM);
629 		chip->duration[TPM_LONG] =
630 		    msecs_to_jiffies(TPM2_DURATION_LONG);
631 
632 		chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
633 		return 0;
634 	}
635 
636 	rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, NULL,
637 			sizeof(cap.timeout));
638 	if (rc == TPM_ERR_INVALID_POSTINIT) {
639 		/* The TPM is not started, we are the first to talk to it.
640 		   Execute a startup command. */
641 		dev_info(&chip->dev, "Issuing TPM_STARTUP\n");
642 		if (tpm_startup(chip, TPM_ST_CLEAR))
643 			return rc;
644 
645 		rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
646 				"attempting to determine the timeouts",
647 				sizeof(cap.timeout));
648 	}
649 
650 	if (rc) {
651 		dev_err(&chip->dev,
652 			"A TPM error (%zd) occurred attempting to determine the timeouts\n",
653 			rc);
654 		return rc;
655 	}
656 
657 	timeout_old[0] = jiffies_to_usecs(chip->timeout_a);
658 	timeout_old[1] = jiffies_to_usecs(chip->timeout_b);
659 	timeout_old[2] = jiffies_to_usecs(chip->timeout_c);
660 	timeout_old[3] = jiffies_to_usecs(chip->timeout_d);
661 	timeout_chip[0] = be32_to_cpu(cap.timeout.a);
662 	timeout_chip[1] = be32_to_cpu(cap.timeout.b);
663 	timeout_chip[2] = be32_to_cpu(cap.timeout.c);
664 	timeout_chip[3] = be32_to_cpu(cap.timeout.d);
665 	memcpy(timeout_eff, timeout_chip, sizeof(timeout_eff));
666 
667 	/*
668 	 * Provide ability for vendor overrides of timeout values in case
669 	 * of misreporting.
670 	 */
671 	if (chip->ops->update_timeouts != NULL)
672 		chip->timeout_adjusted =
673 			chip->ops->update_timeouts(chip, timeout_eff);
674 
675 	if (!chip->timeout_adjusted) {
676 		/* Restore default if chip reported 0 */
677 		int i;
678 
679 		for (i = 0; i < ARRAY_SIZE(timeout_eff); i++) {
680 			if (timeout_eff[i])
681 				continue;
682 
683 			timeout_eff[i] = timeout_old[i];
684 			chip->timeout_adjusted = true;
685 		}
686 
687 		if (timeout_eff[0] != 0 && timeout_eff[0] < 1000) {
688 			/* timeouts in msec rather usec */
689 			for (i = 0; i != ARRAY_SIZE(timeout_eff); i++)
690 				timeout_eff[i] *= 1000;
691 			chip->timeout_adjusted = true;
692 		}
693 	}
694 
695 	/* Report adjusted timeouts */
696 	if (chip->timeout_adjusted) {
697 		dev_info(&chip->dev,
698 			 HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n",
699 			 timeout_chip[0], timeout_eff[0],
700 			 timeout_chip[1], timeout_eff[1],
701 			 timeout_chip[2], timeout_eff[2],
702 			 timeout_chip[3], timeout_eff[3]);
703 	}
704 
705 	chip->timeout_a = usecs_to_jiffies(timeout_eff[0]);
706 	chip->timeout_b = usecs_to_jiffies(timeout_eff[1]);
707 	chip->timeout_c = usecs_to_jiffies(timeout_eff[2]);
708 	chip->timeout_d = usecs_to_jiffies(timeout_eff[3]);
709 
710 	rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap,
711 			"attempting to determine the durations",
712 			sizeof(cap.duration));
713 	if (rc)
714 		return rc;
715 
716 	chip->duration[TPM_SHORT] =
717 		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short));
718 	chip->duration[TPM_MEDIUM] =
719 		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium));
720 	chip->duration[TPM_LONG] =
721 		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long));
722 
723 	/* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
724 	 * value wrong and apparently reports msecs rather than usecs. So we
725 	 * fix up the resulting too-small TPM_SHORT value to make things work.
726 	 * We also scale the TPM_MEDIUM and -_LONG values by 1000.
727 	 */
728 	if (chip->duration[TPM_SHORT] < (HZ / 100)) {
729 		chip->duration[TPM_SHORT] = HZ;
730 		chip->duration[TPM_MEDIUM] *= 1000;
731 		chip->duration[TPM_LONG] *= 1000;
732 		chip->duration_adjusted = true;
733 		dev_info(&chip->dev, "Adjusting TPM timeout parameters.");
734 	}
735 
736 	chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
737 	return 0;
738 }
739 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
740 
741 #define TPM_ORD_CONTINUE_SELFTEST 83
742 #define CONTINUE_SELFTEST_RESULT_SIZE 10
743 
744 static const struct tpm_input_header continue_selftest_header = {
745 	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
746 	.length = cpu_to_be32(10),
747 	.ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
748 };
749 
750 /**
751  * tpm_continue_selftest -- run TPM's selftest
752  * @chip: TPM chip to use
753  *
754  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
755  * a TPM error code.
756  */
757 static int tpm_continue_selftest(struct tpm_chip *chip)
758 {
759 	int rc;
760 	struct tpm_cmd_t cmd;
761 
762 	cmd.header.in = continue_selftest_header;
763 	rc = tpm_transmit_cmd(chip, NULL, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
764 			      0, 0, "continue selftest");
765 	return rc;
766 }
767 
768 #define TPM_ORDINAL_PCRREAD 21
769 #define READ_PCR_RESULT_SIZE 30
770 #define READ_PCR_RESULT_BODY_SIZE 20
771 static const struct tpm_input_header pcrread_header = {
772 	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
773 	.length = cpu_to_be32(14),
774 	.ordinal = cpu_to_be32(TPM_ORDINAL_PCRREAD)
775 };
776 
777 int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
778 {
779 	int rc;
780 	struct tpm_cmd_t cmd;
781 
782 	cmd.header.in = pcrread_header;
783 	cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
784 	rc = tpm_transmit_cmd(chip, NULL, &cmd, READ_PCR_RESULT_SIZE,
785 			      READ_PCR_RESULT_BODY_SIZE, 0,
786 			      "attempting to read a pcr value");
787 
788 	if (rc == 0)
789 		memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
790 		       TPM_DIGEST_SIZE);
791 	return rc;
792 }
793 
794 /**
795  * tpm_is_tpm2 - is the chip a TPM2 chip?
796  * @chip_num:	tpm idx # or ANY
797  *
798  * Returns < 0 on error, and 1 or 0 on success depending whether the chip
799  * is a TPM2 chip.
800  */
801 int tpm_is_tpm2(u32 chip_num)
802 {
803 	struct tpm_chip *chip;
804 	int rc;
805 
806 	chip = tpm_chip_find_get(chip_num);
807 	if (chip == NULL)
808 		return -ENODEV;
809 
810 	rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0;
811 
812 	tpm_put_ops(chip);
813 
814 	return rc;
815 }
816 EXPORT_SYMBOL_GPL(tpm_is_tpm2);
817 
818 /**
819  * tpm_pcr_read - read a pcr value
820  * @chip_num:	tpm idx # or ANY
821  * @pcr_idx:	pcr idx to retrieve
822  * @res_buf:	TPM_PCR value
823  *		size of res_buf is 20 bytes (or NULL if you don't care)
824  *
825  * The TPM driver should be built-in, but for whatever reason it
826  * isn't, protect against the chip disappearing, by incrementing
827  * the module usage count.
828  */
829 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
830 {
831 	struct tpm_chip *chip;
832 	int rc;
833 
834 	chip = tpm_chip_find_get(chip_num);
835 	if (chip == NULL)
836 		return -ENODEV;
837 	if (chip->flags & TPM_CHIP_FLAG_TPM2)
838 		rc = tpm2_pcr_read(chip, pcr_idx, res_buf);
839 	else
840 		rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf);
841 	tpm_put_ops(chip);
842 	return rc;
843 }
844 EXPORT_SYMBOL_GPL(tpm_pcr_read);
845 
846 #define TPM_ORD_PCR_EXTEND 20
847 #define EXTEND_PCR_RESULT_SIZE 34
848 #define EXTEND_PCR_RESULT_BODY_SIZE 20
849 static const struct tpm_input_header pcrextend_header = {
850 	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
851 	.length = cpu_to_be32(34),
852 	.ordinal = cpu_to_be32(TPM_ORD_PCR_EXTEND)
853 };
854 
855 static int tpm1_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash,
856 			   char *log_msg)
857 {
858 	struct tpm_buf buf;
859 	int rc;
860 
861 	rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_PCR_EXTEND);
862 	if (rc)
863 		return rc;
864 
865 	tpm_buf_append_u32(&buf, pcr_idx);
866 	tpm_buf_append(&buf, hash, TPM_DIGEST_SIZE);
867 
868 	rc = tpm_transmit_cmd(chip, NULL, buf.data, EXTEND_PCR_RESULT_SIZE,
869 			      EXTEND_PCR_RESULT_BODY_SIZE, 0, log_msg);
870 	tpm_buf_destroy(&buf);
871 	return rc;
872 }
873 
874 /**
875  * tpm_pcr_extend - extend pcr value with hash
876  * @chip_num:	tpm idx # or AN&
877  * @pcr_idx:	pcr idx to extend
878  * @hash:	hash value used to extend pcr value
879  *
880  * The TPM driver should be built-in, but for whatever reason it
881  * isn't, protect against the chip disappearing, by incrementing
882  * the module usage count.
883  */
884 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
885 {
886 	int rc;
887 	struct tpm_chip *chip;
888 	struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)];
889 	u32 count = 0;
890 	int i;
891 
892 	chip = tpm_chip_find_get(chip_num);
893 	if (chip == NULL)
894 		return -ENODEV;
895 
896 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
897 		memset(digest_list, 0, sizeof(digest_list));
898 
899 		for (i = 0; i < ARRAY_SIZE(chip->active_banks) &&
900 			    chip->active_banks[i] != TPM2_ALG_ERROR; i++) {
901 			digest_list[i].alg_id = chip->active_banks[i];
902 			memcpy(digest_list[i].digest, hash, TPM_DIGEST_SIZE);
903 			count++;
904 		}
905 
906 		rc = tpm2_pcr_extend(chip, pcr_idx, count, digest_list);
907 		tpm_put_ops(chip);
908 		return rc;
909 	}
910 
911 	rc = tpm1_pcr_extend(chip, pcr_idx, hash,
912 			     "attempting extend a PCR value");
913 	tpm_put_ops(chip);
914 	return rc;
915 }
916 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
917 
918 /**
919  * tpm_do_selftest - have the TPM continue its selftest and wait until it
920  *                   can receive further commands
921  * @chip: TPM chip to use
922  *
923  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
924  * a TPM error code.
925  */
926 int tpm_do_selftest(struct tpm_chip *chip)
927 {
928 	int rc;
929 	unsigned int loops;
930 	unsigned int delay_msec = 100;
931 	unsigned long duration;
932 	u8 dummy[TPM_DIGEST_SIZE];
933 
934 	duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST);
935 
936 	loops = jiffies_to_msecs(duration) / delay_msec;
937 
938 	rc = tpm_continue_selftest(chip);
939 	/* This may fail if there was no TPM driver during a suspend/resume
940 	 * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
941 	 */
942 	if (rc)
943 		return rc;
944 
945 	do {
946 		/* Attempt to read a PCR value */
947 		rc = tpm_pcr_read_dev(chip, 0, dummy);
948 
949 		/* Some buggy TPMs will not respond to tpm_tis_ready() for
950 		 * around 300ms while the self test is ongoing, keep trying
951 		 * until the self test duration expires. */
952 		if (rc == -ETIME) {
953 			dev_info(
954 			    &chip->dev, HW_ERR
955 			    "TPM command timed out during continue self test");
956 			msleep(delay_msec);
957 			continue;
958 		}
959 
960 		if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
961 			dev_info(&chip->dev,
962 				 "TPM is disabled/deactivated (0x%X)\n", rc);
963 			/* TPM is disabled and/or deactivated; driver can
964 			 * proceed and TPM does handle commands for
965 			 * suspend/resume correctly
966 			 */
967 			return 0;
968 		}
969 		if (rc != TPM_WARN_DOING_SELFTEST)
970 			return rc;
971 		msleep(delay_msec);
972 	} while (--loops > 0);
973 
974 	return rc;
975 }
976 EXPORT_SYMBOL_GPL(tpm_do_selftest);
977 
978 /**
979  * tpm1_auto_startup - Perform the standard automatic TPM initialization
980  *                     sequence
981  * @chip: TPM chip to use
982  *
983  * Returns 0 on success, < 0 in case of fatal error.
984  */
985 int tpm1_auto_startup(struct tpm_chip *chip)
986 {
987 	int rc;
988 
989 	rc = tpm_get_timeouts(chip);
990 	if (rc)
991 		goto out;
992 	rc = tpm_do_selftest(chip);
993 	if (rc) {
994 		dev_err(&chip->dev, "TPM self test failed\n");
995 		goto out;
996 	}
997 
998 	return rc;
999 out:
1000 	if (rc > 0)
1001 		rc = -ENODEV;
1002 	return rc;
1003 }
1004 
1005 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
1006 {
1007 	struct tpm_chip *chip;
1008 	int rc;
1009 
1010 	chip = tpm_chip_find_get(chip_num);
1011 	if (chip == NULL)
1012 		return -ENODEV;
1013 
1014 	rc = tpm_transmit_cmd(chip, NULL, cmd, buflen, 0, 0,
1015 			      "attempting tpm_cmd");
1016 	tpm_put_ops(chip);
1017 	return rc;
1018 }
1019 EXPORT_SYMBOL_GPL(tpm_send);
1020 
1021 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
1022 					bool check_cancel, bool *canceled)
1023 {
1024 	u8 status = chip->ops->status(chip);
1025 
1026 	*canceled = false;
1027 	if ((status & mask) == mask)
1028 		return true;
1029 	if (check_cancel && chip->ops->req_canceled(chip, status)) {
1030 		*canceled = true;
1031 		return true;
1032 	}
1033 	return false;
1034 }
1035 
1036 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
1037 		      wait_queue_head_t *queue, bool check_cancel)
1038 {
1039 	unsigned long stop;
1040 	long rc;
1041 	u8 status;
1042 	bool canceled = false;
1043 
1044 	/* check current status */
1045 	status = chip->ops->status(chip);
1046 	if ((status & mask) == mask)
1047 		return 0;
1048 
1049 	stop = jiffies + timeout;
1050 
1051 	if (chip->flags & TPM_CHIP_FLAG_IRQ) {
1052 again:
1053 		timeout = stop - jiffies;
1054 		if ((long)timeout <= 0)
1055 			return -ETIME;
1056 		rc = wait_event_interruptible_timeout(*queue,
1057 			wait_for_tpm_stat_cond(chip, mask, check_cancel,
1058 					       &canceled),
1059 			timeout);
1060 		if (rc > 0) {
1061 			if (canceled)
1062 				return -ECANCELED;
1063 			return 0;
1064 		}
1065 		if (rc == -ERESTARTSYS && freezing(current)) {
1066 			clear_thread_flag(TIF_SIGPENDING);
1067 			goto again;
1068 		}
1069 	} else {
1070 		do {
1071 			msleep(TPM_TIMEOUT);
1072 			status = chip->ops->status(chip);
1073 			if ((status & mask) == mask)
1074 				return 0;
1075 		} while (time_before(jiffies, stop));
1076 	}
1077 	return -ETIME;
1078 }
1079 EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
1080 
1081 #define TPM_ORD_SAVESTATE 152
1082 #define SAVESTATE_RESULT_SIZE 10
1083 
1084 static const struct tpm_input_header savestate_header = {
1085 	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
1086 	.length = cpu_to_be32(10),
1087 	.ordinal = cpu_to_be32(TPM_ORD_SAVESTATE)
1088 };
1089 
1090 /*
1091  * We are about to suspend. Save the TPM state
1092  * so that it can be restored.
1093  */
1094 int tpm_pm_suspend(struct device *dev)
1095 {
1096 	struct tpm_chip *chip = dev_get_drvdata(dev);
1097 	struct tpm_cmd_t cmd;
1098 	int rc, try;
1099 
1100 	u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1101 
1102 	if (chip == NULL)
1103 		return -ENODEV;
1104 
1105 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
1106 		tpm2_shutdown(chip, TPM2_SU_STATE);
1107 		return 0;
1108 	}
1109 
1110 	/* for buggy tpm, flush pcrs with extend to selected dummy */
1111 	if (tpm_suspend_pcr)
1112 		rc = tpm1_pcr_extend(chip, tpm_suspend_pcr, dummy_hash,
1113 				     "extending dummy pcr before suspend");
1114 
1115 	/* now do the actual savestate */
1116 	for (try = 0; try < TPM_RETRY; try++) {
1117 		cmd.header.in = savestate_header;
1118 		rc = tpm_transmit_cmd(chip, NULL, &cmd, SAVESTATE_RESULT_SIZE,
1119 				      0, 0, NULL);
1120 
1121 		/*
1122 		 * If the TPM indicates that it is too busy to respond to
1123 		 * this command then retry before giving up.  It can take
1124 		 * several seconds for this TPM to be ready.
1125 		 *
1126 		 * This can happen if the TPM has already been sent the
1127 		 * SaveState command before the driver has loaded.  TCG 1.2
1128 		 * specification states that any communication after SaveState
1129 		 * may cause the TPM to invalidate previously saved state.
1130 		 */
1131 		if (rc != TPM_WARN_RETRY)
1132 			break;
1133 		msleep(TPM_TIMEOUT_RETRY);
1134 	}
1135 
1136 	if (rc)
1137 		dev_err(&chip->dev,
1138 			"Error (%d) sending savestate before suspend\n", rc);
1139 	else if (try > 0)
1140 		dev_warn(&chip->dev, "TPM savestate took %dms\n",
1141 			 try * TPM_TIMEOUT_RETRY);
1142 
1143 	return rc;
1144 }
1145 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1146 
1147 /*
1148  * Resume from a power safe. The BIOS already restored
1149  * the TPM state.
1150  */
1151 int tpm_pm_resume(struct device *dev)
1152 {
1153 	struct tpm_chip *chip = dev_get_drvdata(dev);
1154 
1155 	if (chip == NULL)
1156 		return -ENODEV;
1157 
1158 	return 0;
1159 }
1160 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1161 
1162 #define TPM_GETRANDOM_RESULT_SIZE	18
1163 static const struct tpm_input_header tpm_getrandom_header = {
1164 	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
1165 	.length = cpu_to_be32(14),
1166 	.ordinal = cpu_to_be32(TPM_ORD_GET_RANDOM)
1167 };
1168 
1169 /**
1170  * tpm_get_random() - Get random bytes from the tpm's RNG
1171  * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1172  * @out: destination buffer for the random bytes
1173  * @max: the max number of bytes to write to @out
1174  *
1175  * Returns < 0 on error and the number of bytes read on success
1176  */
1177 int tpm_get_random(u32 chip_num, u8 *out, size_t max)
1178 {
1179 	struct tpm_chip *chip;
1180 	struct tpm_cmd_t tpm_cmd;
1181 	u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA), rlength;
1182 	int err, total = 0, retries = 5;
1183 	u8 *dest = out;
1184 
1185 	if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
1186 		return -EINVAL;
1187 
1188 	chip = tpm_chip_find_get(chip_num);
1189 	if (chip == NULL)
1190 		return -ENODEV;
1191 
1192 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
1193 		err = tpm2_get_random(chip, out, max);
1194 		tpm_put_ops(chip);
1195 		return err;
1196 	}
1197 
1198 	do {
1199 		tpm_cmd.header.in = tpm_getrandom_header;
1200 		tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
1201 
1202 		err = tpm_transmit_cmd(chip, NULL, &tpm_cmd,
1203 				       TPM_GETRANDOM_RESULT_SIZE + num_bytes,
1204 				       offsetof(struct tpm_getrandom_out,
1205 						rng_data),
1206 				       0, "attempting get random");
1207 		if (err)
1208 			break;
1209 
1210 		recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
1211 
1212 		rlength = be32_to_cpu(tpm_cmd.header.out.length);
1213 		if (rlength < offsetof(struct tpm_getrandom_out, rng_data) +
1214 			      recd) {
1215 			total = -EFAULT;
1216 			break;
1217 		}
1218 		memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
1219 
1220 		dest += recd;
1221 		total += recd;
1222 		num_bytes -= recd;
1223 	} while (retries-- && total < max);
1224 
1225 	tpm_put_ops(chip);
1226 	return total ? total : -EIO;
1227 }
1228 EXPORT_SYMBOL_GPL(tpm_get_random);
1229 
1230 /**
1231  * tpm_seal_trusted() - seal a trusted key
1232  * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1233  * @options: authentication values and other options
1234  * @payload: the key data in clear and encrypted form
1235  *
1236  * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips
1237  * are supported.
1238  */
1239 int tpm_seal_trusted(u32 chip_num, struct trusted_key_payload *payload,
1240 		     struct trusted_key_options *options)
1241 {
1242 	struct tpm_chip *chip;
1243 	int rc;
1244 
1245 	chip = tpm_chip_find_get(chip_num);
1246 	if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1247 		return -ENODEV;
1248 
1249 	rc = tpm2_seal_trusted(chip, payload, options);
1250 
1251 	tpm_put_ops(chip);
1252 	return rc;
1253 }
1254 EXPORT_SYMBOL_GPL(tpm_seal_trusted);
1255 
1256 /**
1257  * tpm_unseal_trusted() - unseal a trusted key
1258  * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1259  * @options: authentication values and other options
1260  * @payload: the key data in clear and encrypted form
1261  *
1262  * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips
1263  * are supported.
1264  */
1265 int tpm_unseal_trusted(u32 chip_num, struct trusted_key_payload *payload,
1266 		       struct trusted_key_options *options)
1267 {
1268 	struct tpm_chip *chip;
1269 	int rc;
1270 
1271 	chip = tpm_chip_find_get(chip_num);
1272 	if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1273 		return -ENODEV;
1274 
1275 	rc = tpm2_unseal_trusted(chip, payload, options);
1276 
1277 	tpm_put_ops(chip);
1278 
1279 	return rc;
1280 }
1281 EXPORT_SYMBOL_GPL(tpm_unseal_trusted);
1282 
1283 static int __init tpm_init(void)
1284 {
1285 	int rc;
1286 
1287 	tpm_class = class_create(THIS_MODULE, "tpm");
1288 	if (IS_ERR(tpm_class)) {
1289 		pr_err("couldn't create tpm class\n");
1290 		return PTR_ERR(tpm_class);
1291 	}
1292 
1293 	tpmrm_class = class_create(THIS_MODULE, "tpmrm");
1294 	if (IS_ERR(tpmrm_class)) {
1295 		pr_err("couldn't create tpmrm class\n");
1296 		class_destroy(tpm_class);
1297 		return PTR_ERR(tpmrm_class);
1298 	}
1299 
1300 	rc = alloc_chrdev_region(&tpm_devt, 0, 2*TPM_NUM_DEVICES, "tpm");
1301 	if (rc < 0) {
1302 		pr_err("tpm: failed to allocate char dev region\n");
1303 		class_destroy(tpmrm_class);
1304 		class_destroy(tpm_class);
1305 		return rc;
1306 	}
1307 
1308 	return 0;
1309 }
1310 
1311 static void __exit tpm_exit(void)
1312 {
1313 	idr_destroy(&dev_nums_idr);
1314 	class_destroy(tpm_class);
1315 	class_destroy(tpmrm_class);
1316 	unregister_chrdev_region(tpm_devt, 2*TPM_NUM_DEVICES);
1317 }
1318 
1319 subsys_initcall(tpm_init);
1320 module_exit(tpm_exit);
1321 
1322 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1323 MODULE_DESCRIPTION("TPM Driver");
1324 MODULE_VERSION("2.0");
1325 MODULE_LICENSE("GPL");
1326