xref: /openbmc/linux/drivers/char/tpm/tpm-interface.c (revision 68198dca)
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 		tpm_msleep(TPM_TIMEOUT);
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_ORD_STARTUP 153
544 #define TPM_ST_CLEAR 1
545 
546 /**
547  * tpm_startup - turn on the TPM
548  * @chip: TPM chip to use
549  *
550  * Normally the firmware should start the TPM. This function is provided as a
551  * workaround if this does not happen. A legal case for this could be for
552  * example when a TPM emulator is used.
553  *
554  * Return: same as tpm_transmit_cmd()
555  */
556 int tpm_startup(struct tpm_chip *chip)
557 {
558 	struct tpm_buf buf;
559 	int rc;
560 
561 	dev_info(&chip->dev, "starting up the TPM manually\n");
562 
563 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
564 		rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_STARTUP);
565 		if (rc < 0)
566 			return rc;
567 
568 		tpm_buf_append_u16(&buf, TPM2_SU_CLEAR);
569 	} else {
570 		rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_STARTUP);
571 		if (rc < 0)
572 			return rc;
573 
574 		tpm_buf_append_u16(&buf, TPM_ST_CLEAR);
575 	}
576 
577 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
578 			      "attempting to start the TPM");
579 
580 	tpm_buf_destroy(&buf);
581 	return rc;
582 }
583 
584 #define TPM_DIGEST_SIZE 20
585 #define TPM_RET_CODE_IDX 6
586 #define TPM_INTERNAL_RESULT_SIZE 200
587 #define TPM_ORD_GET_CAP 101
588 #define TPM_ORD_GET_RANDOM 70
589 
590 static const struct tpm_input_header tpm_getcap_header = {
591 	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
592 	.length = cpu_to_be32(22),
593 	.ordinal = cpu_to_be32(TPM_ORD_GET_CAP)
594 };
595 
596 ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
597 		   const char *desc, size_t min_cap_length)
598 {
599 	struct tpm_buf buf;
600 	int rc;
601 
602 	rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_CAP);
603 	if (rc)
604 		return rc;
605 
606 	if (subcap_id == TPM_CAP_VERSION_1_1 ||
607 	    subcap_id == TPM_CAP_VERSION_1_2) {
608 		tpm_buf_append_u32(&buf, subcap_id);
609 		tpm_buf_append_u32(&buf, 0);
610 	} else {
611 		if (subcap_id == TPM_CAP_FLAG_PERM ||
612 		    subcap_id == TPM_CAP_FLAG_VOL)
613 			tpm_buf_append_u32(&buf, TPM_CAP_FLAG);
614 		else
615 			tpm_buf_append_u32(&buf, TPM_CAP_PROP);
616 
617 		tpm_buf_append_u32(&buf, 4);
618 		tpm_buf_append_u32(&buf, subcap_id);
619 	}
620 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE,
621 			      min_cap_length, 0, desc);
622 	if (!rc)
623 		*cap = *(cap_t *)&buf.data[TPM_HEADER_SIZE + 4];
624 
625 	tpm_buf_destroy(&buf);
626 	return rc;
627 }
628 EXPORT_SYMBOL_GPL(tpm_getcap);
629 
630 int tpm_get_timeouts(struct tpm_chip *chip)
631 {
632 	cap_t cap;
633 	unsigned long timeout_old[4], timeout_chip[4], timeout_eff[4];
634 	ssize_t rc;
635 
636 	if (chip->flags & TPM_CHIP_FLAG_HAVE_TIMEOUTS)
637 		return 0;
638 
639 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
640 		/* Fixed timeouts for TPM2 */
641 		chip->timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
642 		chip->timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
643 		chip->timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
644 		chip->timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
645 		chip->duration[TPM_SHORT] =
646 		    msecs_to_jiffies(TPM2_DURATION_SHORT);
647 		chip->duration[TPM_MEDIUM] =
648 		    msecs_to_jiffies(TPM2_DURATION_MEDIUM);
649 		chip->duration[TPM_LONG] =
650 		    msecs_to_jiffies(TPM2_DURATION_LONG);
651 
652 		chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
653 		return 0;
654 	}
655 
656 	rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, NULL,
657 			sizeof(cap.timeout));
658 	if (rc == TPM_ERR_INVALID_POSTINIT) {
659 		if (tpm_startup(chip))
660 			return rc;
661 
662 		rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
663 				"attempting to determine the timeouts",
664 				sizeof(cap.timeout));
665 	}
666 
667 	if (rc) {
668 		dev_err(&chip->dev,
669 			"A TPM error (%zd) occurred attempting to determine the timeouts\n",
670 			rc);
671 		return rc;
672 	}
673 
674 	timeout_old[0] = jiffies_to_usecs(chip->timeout_a);
675 	timeout_old[1] = jiffies_to_usecs(chip->timeout_b);
676 	timeout_old[2] = jiffies_to_usecs(chip->timeout_c);
677 	timeout_old[3] = jiffies_to_usecs(chip->timeout_d);
678 	timeout_chip[0] = be32_to_cpu(cap.timeout.a);
679 	timeout_chip[1] = be32_to_cpu(cap.timeout.b);
680 	timeout_chip[2] = be32_to_cpu(cap.timeout.c);
681 	timeout_chip[3] = be32_to_cpu(cap.timeout.d);
682 	memcpy(timeout_eff, timeout_chip, sizeof(timeout_eff));
683 
684 	/*
685 	 * Provide ability for vendor overrides of timeout values in case
686 	 * of misreporting.
687 	 */
688 	if (chip->ops->update_timeouts != NULL)
689 		chip->timeout_adjusted =
690 			chip->ops->update_timeouts(chip, timeout_eff);
691 
692 	if (!chip->timeout_adjusted) {
693 		/* Restore default if chip reported 0 */
694 		int i;
695 
696 		for (i = 0; i < ARRAY_SIZE(timeout_eff); i++) {
697 			if (timeout_eff[i])
698 				continue;
699 
700 			timeout_eff[i] = timeout_old[i];
701 			chip->timeout_adjusted = true;
702 		}
703 
704 		if (timeout_eff[0] != 0 && timeout_eff[0] < 1000) {
705 			/* timeouts in msec rather usec */
706 			for (i = 0; i != ARRAY_SIZE(timeout_eff); i++)
707 				timeout_eff[i] *= 1000;
708 			chip->timeout_adjusted = true;
709 		}
710 	}
711 
712 	/* Report adjusted timeouts */
713 	if (chip->timeout_adjusted) {
714 		dev_info(&chip->dev,
715 			 HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n",
716 			 timeout_chip[0], timeout_eff[0],
717 			 timeout_chip[1], timeout_eff[1],
718 			 timeout_chip[2], timeout_eff[2],
719 			 timeout_chip[3], timeout_eff[3]);
720 	}
721 
722 	chip->timeout_a = usecs_to_jiffies(timeout_eff[0]);
723 	chip->timeout_b = usecs_to_jiffies(timeout_eff[1]);
724 	chip->timeout_c = usecs_to_jiffies(timeout_eff[2]);
725 	chip->timeout_d = usecs_to_jiffies(timeout_eff[3]);
726 
727 	rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap,
728 			"attempting to determine the durations",
729 			sizeof(cap.duration));
730 	if (rc)
731 		return rc;
732 
733 	chip->duration[TPM_SHORT] =
734 		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short));
735 	chip->duration[TPM_MEDIUM] =
736 		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium));
737 	chip->duration[TPM_LONG] =
738 		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long));
739 
740 	/* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
741 	 * value wrong and apparently reports msecs rather than usecs. So we
742 	 * fix up the resulting too-small TPM_SHORT value to make things work.
743 	 * We also scale the TPM_MEDIUM and -_LONG values by 1000.
744 	 */
745 	if (chip->duration[TPM_SHORT] < (HZ / 100)) {
746 		chip->duration[TPM_SHORT] = HZ;
747 		chip->duration[TPM_MEDIUM] *= 1000;
748 		chip->duration[TPM_LONG] *= 1000;
749 		chip->duration_adjusted = true;
750 		dev_info(&chip->dev, "Adjusting TPM timeout parameters.");
751 	}
752 
753 	chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
754 	return 0;
755 }
756 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
757 
758 #define TPM_ORD_CONTINUE_SELFTEST 83
759 #define CONTINUE_SELFTEST_RESULT_SIZE 10
760 
761 static const struct tpm_input_header continue_selftest_header = {
762 	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
763 	.length = cpu_to_be32(10),
764 	.ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
765 };
766 
767 /**
768  * tpm_continue_selftest -- run TPM's selftest
769  * @chip: TPM chip to use
770  *
771  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
772  * a TPM error code.
773  */
774 static int tpm_continue_selftest(struct tpm_chip *chip)
775 {
776 	int rc;
777 	struct tpm_cmd_t cmd;
778 
779 	cmd.header.in = continue_selftest_header;
780 	rc = tpm_transmit_cmd(chip, NULL, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
781 			      0, 0, "continue selftest");
782 	return rc;
783 }
784 
785 #define TPM_ORDINAL_PCRREAD 21
786 #define READ_PCR_RESULT_SIZE 30
787 #define READ_PCR_RESULT_BODY_SIZE 20
788 static const struct tpm_input_header pcrread_header = {
789 	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
790 	.length = cpu_to_be32(14),
791 	.ordinal = cpu_to_be32(TPM_ORDINAL_PCRREAD)
792 };
793 
794 int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
795 {
796 	int rc;
797 	struct tpm_cmd_t cmd;
798 
799 	cmd.header.in = pcrread_header;
800 	cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
801 	rc = tpm_transmit_cmd(chip, NULL, &cmd, READ_PCR_RESULT_SIZE,
802 			      READ_PCR_RESULT_BODY_SIZE, 0,
803 			      "attempting to read a pcr value");
804 
805 	if (rc == 0)
806 		memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
807 		       TPM_DIGEST_SIZE);
808 	return rc;
809 }
810 
811 /**
812  * tpm_is_tpm2 - is the chip a TPM2 chip?
813  * @chip_num:	tpm idx # or ANY
814  *
815  * Returns < 0 on error, and 1 or 0 on success depending whether the chip
816  * is a TPM2 chip.
817  */
818 int tpm_is_tpm2(u32 chip_num)
819 {
820 	struct tpm_chip *chip;
821 	int rc;
822 
823 	chip = tpm_chip_find_get(chip_num);
824 	if (chip == NULL)
825 		return -ENODEV;
826 
827 	rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0;
828 
829 	tpm_put_ops(chip);
830 
831 	return rc;
832 }
833 EXPORT_SYMBOL_GPL(tpm_is_tpm2);
834 
835 /**
836  * tpm_pcr_read - read a pcr value
837  * @chip_num:	tpm idx # or ANY
838  * @pcr_idx:	pcr idx to retrieve
839  * @res_buf:	TPM_PCR value
840  *		size of res_buf is 20 bytes (or NULL if you don't care)
841  *
842  * The TPM driver should be built-in, but for whatever reason it
843  * isn't, protect against the chip disappearing, by incrementing
844  * the module usage count.
845  */
846 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
847 {
848 	struct tpm_chip *chip;
849 	int rc;
850 
851 	chip = tpm_chip_find_get(chip_num);
852 	if (chip == NULL)
853 		return -ENODEV;
854 	if (chip->flags & TPM_CHIP_FLAG_TPM2)
855 		rc = tpm2_pcr_read(chip, pcr_idx, res_buf);
856 	else
857 		rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf);
858 	tpm_put_ops(chip);
859 	return rc;
860 }
861 EXPORT_SYMBOL_GPL(tpm_pcr_read);
862 
863 #define TPM_ORD_PCR_EXTEND 20
864 #define EXTEND_PCR_RESULT_SIZE 34
865 #define EXTEND_PCR_RESULT_BODY_SIZE 20
866 static const struct tpm_input_header pcrextend_header = {
867 	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
868 	.length = cpu_to_be32(34),
869 	.ordinal = cpu_to_be32(TPM_ORD_PCR_EXTEND)
870 };
871 
872 static int tpm1_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash,
873 			   char *log_msg)
874 {
875 	struct tpm_buf buf;
876 	int rc;
877 
878 	rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_PCR_EXTEND);
879 	if (rc)
880 		return rc;
881 
882 	tpm_buf_append_u32(&buf, pcr_idx);
883 	tpm_buf_append(&buf, hash, TPM_DIGEST_SIZE);
884 
885 	rc = tpm_transmit_cmd(chip, NULL, buf.data, EXTEND_PCR_RESULT_SIZE,
886 			      EXTEND_PCR_RESULT_BODY_SIZE, 0, log_msg);
887 	tpm_buf_destroy(&buf);
888 	return rc;
889 }
890 
891 /**
892  * tpm_pcr_extend - extend pcr value with hash
893  * @chip_num:	tpm idx # or AN&
894  * @pcr_idx:	pcr idx to extend
895  * @hash:	hash value used to extend pcr value
896  *
897  * The TPM driver should be built-in, but for whatever reason it
898  * isn't, protect against the chip disappearing, by incrementing
899  * the module usage count.
900  */
901 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
902 {
903 	int rc;
904 	struct tpm_chip *chip;
905 	struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)];
906 	u32 count = 0;
907 	int i;
908 
909 	chip = tpm_chip_find_get(chip_num);
910 	if (chip == NULL)
911 		return -ENODEV;
912 
913 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
914 		memset(digest_list, 0, sizeof(digest_list));
915 
916 		for (i = 0; i < ARRAY_SIZE(chip->active_banks) &&
917 			    chip->active_banks[i] != TPM2_ALG_ERROR; i++) {
918 			digest_list[i].alg_id = chip->active_banks[i];
919 			memcpy(digest_list[i].digest, hash, TPM_DIGEST_SIZE);
920 			count++;
921 		}
922 
923 		rc = tpm2_pcr_extend(chip, pcr_idx, count, digest_list);
924 		tpm_put_ops(chip);
925 		return rc;
926 	}
927 
928 	rc = tpm1_pcr_extend(chip, pcr_idx, hash,
929 			     "attempting extend a PCR value");
930 	tpm_put_ops(chip);
931 	return rc;
932 }
933 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
934 
935 /**
936  * tpm_do_selftest - have the TPM continue its selftest and wait until it
937  *                   can receive further commands
938  * @chip: TPM chip to use
939  *
940  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
941  * a TPM error code.
942  */
943 int tpm_do_selftest(struct tpm_chip *chip)
944 {
945 	int rc;
946 	unsigned int loops;
947 	unsigned int delay_msec = 100;
948 	unsigned long duration;
949 	u8 dummy[TPM_DIGEST_SIZE];
950 
951 	duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST);
952 
953 	loops = jiffies_to_msecs(duration) / delay_msec;
954 
955 	rc = tpm_continue_selftest(chip);
956 	/* This may fail if there was no TPM driver during a suspend/resume
957 	 * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
958 	 */
959 	if (rc)
960 		return rc;
961 
962 	do {
963 		/* Attempt to read a PCR value */
964 		rc = tpm_pcr_read_dev(chip, 0, dummy);
965 
966 		/* Some buggy TPMs will not respond to tpm_tis_ready() for
967 		 * around 300ms while the self test is ongoing, keep trying
968 		 * until the self test duration expires. */
969 		if (rc == -ETIME) {
970 			dev_info(
971 			    &chip->dev, HW_ERR
972 			    "TPM command timed out during continue self test");
973 			tpm_msleep(delay_msec);
974 			continue;
975 		}
976 
977 		if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
978 			dev_info(&chip->dev,
979 				 "TPM is disabled/deactivated (0x%X)\n", rc);
980 			/* TPM is disabled and/or deactivated; driver can
981 			 * proceed and TPM does handle commands for
982 			 * suspend/resume correctly
983 			 */
984 			return 0;
985 		}
986 		if (rc != TPM_WARN_DOING_SELFTEST)
987 			return rc;
988 		tpm_msleep(delay_msec);
989 	} while (--loops > 0);
990 
991 	return rc;
992 }
993 EXPORT_SYMBOL_GPL(tpm_do_selftest);
994 
995 /**
996  * tpm1_auto_startup - Perform the standard automatic TPM initialization
997  *                     sequence
998  * @chip: TPM chip to use
999  *
1000  * Returns 0 on success, < 0 in case of fatal error.
1001  */
1002 int tpm1_auto_startup(struct tpm_chip *chip)
1003 {
1004 	int rc;
1005 
1006 	rc = tpm_get_timeouts(chip);
1007 	if (rc)
1008 		goto out;
1009 	rc = tpm_do_selftest(chip);
1010 	if (rc) {
1011 		dev_err(&chip->dev, "TPM self test failed\n");
1012 		goto out;
1013 	}
1014 
1015 	return rc;
1016 out:
1017 	if (rc > 0)
1018 		rc = -ENODEV;
1019 	return rc;
1020 }
1021 
1022 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
1023 {
1024 	struct tpm_chip *chip;
1025 	int rc;
1026 
1027 	chip = tpm_chip_find_get(chip_num);
1028 	if (chip == NULL)
1029 		return -ENODEV;
1030 
1031 	rc = tpm_transmit_cmd(chip, NULL, cmd, buflen, 0, 0,
1032 			      "attempting tpm_cmd");
1033 	tpm_put_ops(chip);
1034 	return rc;
1035 }
1036 EXPORT_SYMBOL_GPL(tpm_send);
1037 
1038 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
1039 					bool check_cancel, bool *canceled)
1040 {
1041 	u8 status = chip->ops->status(chip);
1042 
1043 	*canceled = false;
1044 	if ((status & mask) == mask)
1045 		return true;
1046 	if (check_cancel && chip->ops->req_canceled(chip, status)) {
1047 		*canceled = true;
1048 		return true;
1049 	}
1050 	return false;
1051 }
1052 
1053 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
1054 		      wait_queue_head_t *queue, bool check_cancel)
1055 {
1056 	unsigned long stop;
1057 	long rc;
1058 	u8 status;
1059 	bool canceled = false;
1060 
1061 	/* check current status */
1062 	status = chip->ops->status(chip);
1063 	if ((status & mask) == mask)
1064 		return 0;
1065 
1066 	stop = jiffies + timeout;
1067 
1068 	if (chip->flags & TPM_CHIP_FLAG_IRQ) {
1069 again:
1070 		timeout = stop - jiffies;
1071 		if ((long)timeout <= 0)
1072 			return -ETIME;
1073 		rc = wait_event_interruptible_timeout(*queue,
1074 			wait_for_tpm_stat_cond(chip, mask, check_cancel,
1075 					       &canceled),
1076 			timeout);
1077 		if (rc > 0) {
1078 			if (canceled)
1079 				return -ECANCELED;
1080 			return 0;
1081 		}
1082 		if (rc == -ERESTARTSYS && freezing(current)) {
1083 			clear_thread_flag(TIF_SIGPENDING);
1084 			goto again;
1085 		}
1086 	} else {
1087 		do {
1088 			tpm_msleep(TPM_TIMEOUT);
1089 			status = chip->ops->status(chip);
1090 			if ((status & mask) == mask)
1091 				return 0;
1092 		} while (time_before(jiffies, stop));
1093 	}
1094 	return -ETIME;
1095 }
1096 EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
1097 
1098 #define TPM_ORD_SAVESTATE 152
1099 #define SAVESTATE_RESULT_SIZE 10
1100 
1101 static const struct tpm_input_header savestate_header = {
1102 	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
1103 	.length = cpu_to_be32(10),
1104 	.ordinal = cpu_to_be32(TPM_ORD_SAVESTATE)
1105 };
1106 
1107 /*
1108  * We are about to suspend. Save the TPM state
1109  * so that it can be restored.
1110  */
1111 int tpm_pm_suspend(struct device *dev)
1112 {
1113 	struct tpm_chip *chip = dev_get_drvdata(dev);
1114 	struct tpm_cmd_t cmd;
1115 	int rc, try;
1116 
1117 	u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1118 
1119 	if (chip == NULL)
1120 		return -ENODEV;
1121 
1122 	if (chip->flags & TPM_CHIP_FLAG_ALWAYS_POWERED)
1123 		return 0;
1124 
1125 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
1126 		tpm2_shutdown(chip, TPM2_SU_STATE);
1127 		return 0;
1128 	}
1129 
1130 	/* for buggy tpm, flush pcrs with extend to selected dummy */
1131 	if (tpm_suspend_pcr)
1132 		rc = tpm1_pcr_extend(chip, tpm_suspend_pcr, dummy_hash,
1133 				     "extending dummy pcr before suspend");
1134 
1135 	/* now do the actual savestate */
1136 	for (try = 0; try < TPM_RETRY; try++) {
1137 		cmd.header.in = savestate_header;
1138 		rc = tpm_transmit_cmd(chip, NULL, &cmd, SAVESTATE_RESULT_SIZE,
1139 				      0, 0, NULL);
1140 
1141 		/*
1142 		 * If the TPM indicates that it is too busy to respond to
1143 		 * this command then retry before giving up.  It can take
1144 		 * several seconds for this TPM to be ready.
1145 		 *
1146 		 * This can happen if the TPM has already been sent the
1147 		 * SaveState command before the driver has loaded.  TCG 1.2
1148 		 * specification states that any communication after SaveState
1149 		 * may cause the TPM to invalidate previously saved state.
1150 		 */
1151 		if (rc != TPM_WARN_RETRY)
1152 			break;
1153 		tpm_msleep(TPM_TIMEOUT_RETRY);
1154 	}
1155 
1156 	if (rc)
1157 		dev_err(&chip->dev,
1158 			"Error (%d) sending savestate before suspend\n", rc);
1159 	else if (try > 0)
1160 		dev_warn(&chip->dev, "TPM savestate took %dms\n",
1161 			 try * TPM_TIMEOUT_RETRY);
1162 
1163 	return rc;
1164 }
1165 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1166 
1167 /*
1168  * Resume from a power safe. The BIOS already restored
1169  * the TPM state.
1170  */
1171 int tpm_pm_resume(struct device *dev)
1172 {
1173 	struct tpm_chip *chip = dev_get_drvdata(dev);
1174 
1175 	if (chip == NULL)
1176 		return -ENODEV;
1177 
1178 	return 0;
1179 }
1180 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1181 
1182 #define TPM_GETRANDOM_RESULT_SIZE	18
1183 static const struct tpm_input_header tpm_getrandom_header = {
1184 	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
1185 	.length = cpu_to_be32(14),
1186 	.ordinal = cpu_to_be32(TPM_ORD_GET_RANDOM)
1187 };
1188 
1189 /**
1190  * tpm_get_random() - Get random bytes from the tpm's RNG
1191  * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1192  * @out: destination buffer for the random bytes
1193  * @max: the max number of bytes to write to @out
1194  *
1195  * Returns < 0 on error and the number of bytes read on success
1196  */
1197 int tpm_get_random(u32 chip_num, u8 *out, size_t max)
1198 {
1199 	struct tpm_chip *chip;
1200 	struct tpm_cmd_t tpm_cmd;
1201 	u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA), rlength;
1202 	int err, total = 0, retries = 5;
1203 	u8 *dest = out;
1204 
1205 	if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
1206 		return -EINVAL;
1207 
1208 	chip = tpm_chip_find_get(chip_num);
1209 	if (chip == NULL)
1210 		return -ENODEV;
1211 
1212 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
1213 		err = tpm2_get_random(chip, out, max);
1214 		tpm_put_ops(chip);
1215 		return err;
1216 	}
1217 
1218 	do {
1219 		tpm_cmd.header.in = tpm_getrandom_header;
1220 		tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
1221 
1222 		err = tpm_transmit_cmd(chip, NULL, &tpm_cmd,
1223 				       TPM_GETRANDOM_RESULT_SIZE + num_bytes,
1224 				       offsetof(struct tpm_getrandom_out,
1225 						rng_data),
1226 				       0, "attempting get random");
1227 		if (err)
1228 			break;
1229 
1230 		recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
1231 
1232 		rlength = be32_to_cpu(tpm_cmd.header.out.length);
1233 		if (rlength < offsetof(struct tpm_getrandom_out, rng_data) +
1234 			      recd) {
1235 			total = -EFAULT;
1236 			break;
1237 		}
1238 		memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
1239 
1240 		dest += recd;
1241 		total += recd;
1242 		num_bytes -= recd;
1243 	} while (retries-- && total < max);
1244 
1245 	tpm_put_ops(chip);
1246 	return total ? total : -EIO;
1247 }
1248 EXPORT_SYMBOL_GPL(tpm_get_random);
1249 
1250 /**
1251  * tpm_seal_trusted() - seal a trusted key
1252  * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1253  * @options: authentication values and other options
1254  * @payload: the key data in clear and encrypted form
1255  *
1256  * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips
1257  * are supported.
1258  */
1259 int tpm_seal_trusted(u32 chip_num, struct trusted_key_payload *payload,
1260 		     struct trusted_key_options *options)
1261 {
1262 	struct tpm_chip *chip;
1263 	int rc;
1264 
1265 	chip = tpm_chip_find_get(chip_num);
1266 	if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1267 		return -ENODEV;
1268 
1269 	rc = tpm2_seal_trusted(chip, payload, options);
1270 
1271 	tpm_put_ops(chip);
1272 	return rc;
1273 }
1274 EXPORT_SYMBOL_GPL(tpm_seal_trusted);
1275 
1276 /**
1277  * tpm_unseal_trusted() - unseal a trusted key
1278  * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1279  * @options: authentication values and other options
1280  * @payload: the key data in clear and encrypted form
1281  *
1282  * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips
1283  * are supported.
1284  */
1285 int tpm_unseal_trusted(u32 chip_num, struct trusted_key_payload *payload,
1286 		       struct trusted_key_options *options)
1287 {
1288 	struct tpm_chip *chip;
1289 	int rc;
1290 
1291 	chip = tpm_chip_find_get(chip_num);
1292 	if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1293 		return -ENODEV;
1294 
1295 	rc = tpm2_unseal_trusted(chip, payload, options);
1296 
1297 	tpm_put_ops(chip);
1298 
1299 	return rc;
1300 }
1301 EXPORT_SYMBOL_GPL(tpm_unseal_trusted);
1302 
1303 static int __init tpm_init(void)
1304 {
1305 	int rc;
1306 
1307 	tpm_class = class_create(THIS_MODULE, "tpm");
1308 	if (IS_ERR(tpm_class)) {
1309 		pr_err("couldn't create tpm class\n");
1310 		return PTR_ERR(tpm_class);
1311 	}
1312 
1313 	tpmrm_class = class_create(THIS_MODULE, "tpmrm");
1314 	if (IS_ERR(tpmrm_class)) {
1315 		pr_err("couldn't create tpmrm class\n");
1316 		class_destroy(tpm_class);
1317 		return PTR_ERR(tpmrm_class);
1318 	}
1319 
1320 	rc = alloc_chrdev_region(&tpm_devt, 0, 2*TPM_NUM_DEVICES, "tpm");
1321 	if (rc < 0) {
1322 		pr_err("tpm: failed to allocate char dev region\n");
1323 		class_destroy(tpmrm_class);
1324 		class_destroy(tpm_class);
1325 		return rc;
1326 	}
1327 
1328 	return 0;
1329 }
1330 
1331 static void __exit tpm_exit(void)
1332 {
1333 	idr_destroy(&dev_nums_idr);
1334 	class_destroy(tpm_class);
1335 	class_destroy(tpmrm_class);
1336 	unregister_chrdev_region(tpm_devt, 2*TPM_NUM_DEVICES);
1337 }
1338 
1339 subsys_initcall(tpm_init);
1340 module_exit(tpm_exit);
1341 
1342 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1343 MODULE_DESCRIPTION("TPM Driver");
1344 MODULE_VERSION("2.0");
1345 MODULE_LICENSE("GPL");
1346