summaryrefslogtreecommitdiffstats
path: root/drivers/char/tpm/tpm2-cmd.c
blob: 011909a9be9627632bd1d1ec19230d5945d86719 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
/*
 * Copyright (C) 2014 Intel Corporation
 *
 * Authors:
 * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
 *
 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
 *
 * This file contains TPM2 protocol implementations of the commands
 * used by the kernel internally.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; version 2
 * of the License.
 */

#include "tpm.h"

struct tpm2_startup_in {
	__be16	startup_type;
} __packed;

struct tpm2_self_test_in {
	u8	full_test;
} __packed;

struct tpm2_pcr_read_in {
	__be32	pcr_selects_cnt;
	__be16	hash_alg;
	u8	pcr_select_size;
	u8	pcr_select[TPM2_PCR_SELECT_MIN];
} __packed;

struct tpm2_pcr_read_out {
	__be32	update_cnt;
	__be32	pcr_selects_cnt;
	__be16	hash_alg;
	u8	pcr_select_size;
	u8	pcr_select[TPM2_PCR_SELECT_MIN];
	__be32	digests_cnt;
	__be16	digest_size;
	u8	digest[TPM_DIGEST_SIZE];
} __packed;

struct tpm2_null_auth_area {
	__be32			handle;
	__be16			nonce_size;
	u8			attributes;
	__be16			auth_size;
} __packed;

struct tpm2_pcr_extend_in {
	__be32				pcr_idx;
	__be32				auth_area_size;
	struct tpm2_null_auth_area	auth_area;
	__be32				digest_cnt;
	__be16				hash_alg;
	u8				digest[TPM_DIGEST_SIZE];
} __packed;

struct tpm2_get_tpm_pt_in {
	__be32	cap_id;
	__be32	property_id;
	__be32	property_cnt;
} __packed;

struct tpm2_get_tpm_pt_out {
	u8	more_data;
	__be32	subcap_id;
	__be32	property_cnt;
	__be32	property_id;
	__be32	value;
} __packed;

struct tpm2_get_random_in {
	__be16	size;
} __packed;

struct tpm2_get_random_out {
	__be16	size;
	u8	buffer[TPM_MAX_RNG_DATA];
} __packed;

union tpm2_cmd_params {
	struct	tpm2_startup_in		startup_in;
	struct	tpm2_self_test_in	selftest_in;
	struct	tpm2_pcr_read_in	pcrread_in;
	struct	tpm2_pcr_read_out	pcrread_out;
	struct	tpm2_pcr_extend_in	pcrextend_in;
	struct	tpm2_get_tpm_pt_in	get_tpm_pt_in;
	struct	tpm2_get_tpm_pt_out	get_tpm_pt_out;
	struct	tpm2_get_random_in	getrandom_in;
	struct	tpm2_get_random_out	getrandom_out;
};

struct tpm2_cmd {
	tpm_cmd_header		header;
	union tpm2_cmd_params	params;
} __packed;

/*
 * Array with one entry per ordinal defining the maximum amount
 * of time the chip could take to return the result. The values
 * of the SHORT, MEDIUM, and LONG durations are taken from the
 * PC Client Profile (PTP) specification.
 */
static const u8 tpm2_ordinal_duration[TPM2_CC_LAST - TPM2_CC_FIRST + 1] = {
	TPM_UNDEFINED,		/* 11F */
	TPM_UNDEFINED,		/* 120 */
	TPM_LONG,		/* 121 */
	TPM_UNDEFINED,		/* 122 */
	TPM_UNDEFINED,		/* 123 */
	TPM_UNDEFINED,		/* 124 */
	TPM_UNDEFINED,		/* 125 */
	TPM_UNDEFINED,		/* 126 */
	TPM_UNDEFINED,		/* 127 */
	TPM_UNDEFINED,		/* 128 */
	TPM_LONG,		/* 129 */
	TPM_UNDEFINED,		/* 12a */
	TPM_UNDEFINED,		/* 12b */
	TPM_UNDEFINED,		/* 12c */
	TPM_UNDEFINED,		/* 12d */
	TPM_UNDEFINED,		/* 12e */
	TPM_UNDEFINED,		/* 12f */
	TPM_UNDEFINED,		/* 130 */
	TPM_UNDEFINED,		/* 131 */
	TPM_UNDEFINED,		/* 132 */
	TPM_UNDEFINED,		/* 133 */
	TPM_UNDEFINED,		/* 134 */
	TPM_UNDEFINED,		/* 135 */
	TPM_UNDEFINED,		/* 136 */
	TPM_UNDEFINED,		/* 137 */
	TPM_UNDEFINED,		/* 138 */
	TPM_UNDEFINED,		/* 139 */
	TPM_UNDEFINED,		/* 13a */
	TPM_UNDEFINED,		/* 13b */
	TPM_UNDEFINED,		/* 13c */
	TPM_UNDEFINED,		/* 13d */
	TPM_MEDIUM,		/* 13e */
	TPM_UNDEFINED,		/* 13f */
	TPM_UNDEFINED,		/* 140 */
	TPM_UNDEFINED,		/* 141 */
	TPM_UNDEFINED,		/* 142 */
	TPM_LONG,		/* 143 */
	TPM_MEDIUM,		/* 144 */
	TPM_UNDEFINED,		/* 145 */
	TPM_UNDEFINED,		/* 146 */
	TPM_UNDEFINED,		/* 147 */
	TPM_UNDEFINED,		/* 148 */
	TPM_UNDEFINED,		/* 149 */
	TPM_UNDEFINED,		/* 14a */
	TPM_UNDEFINED,		/* 14b */
	TPM_UNDEFINED,		/* 14c */
	TPM_UNDEFINED,		/* 14d */
	TPM_LONG,		/* 14e */
	TPM_UNDEFINED,		/* 14f */
	TPM_UNDEFINED,		/* 150 */
	TPM_UNDEFINED,		/* 151 */
	TPM_UNDEFINED,		/* 152 */
	TPM_UNDEFINED,		/* 153 */
	TPM_UNDEFINED,		/* 154 */
	TPM_UNDEFINED,		/* 155 */
	TPM_UNDEFINED,		/* 156 */
	TPM_UNDEFINED,		/* 157 */
	TPM_UNDEFINED,		/* 158 */
	TPM_UNDEFINED,		/* 159 */
	TPM_UNDEFINED,		/* 15a */
	TPM_UNDEFINED,		/* 15b */
	TPM_MEDIUM,		/* 15c */
	TPM_UNDEFINED,		/* 15d */
	TPM_UNDEFINED,		/* 15e */
	TPM_UNDEFINED,		/* 15f */
	TPM_UNDEFINED,		/* 160 */
	TPM_UNDEFINED,		/* 161 */
	TPM_UNDEFINED,		/* 162 */
	TPM_UNDEFINED,		/* 163 */
	TPM_UNDEFINED,		/* 164 */
	TPM_UNDEFINED,		/* 165 */
	TPM_UNDEFINED,		/* 166 */
	TPM_UNDEFINED,		/* 167 */
	TPM_UNDEFINED,		/* 168 */
	TPM_UNDEFINED,		/* 169 */
	TPM_UNDEFINED,		/* 16a */
	TPM_UNDEFINED,		/* 16b */
	TPM_UNDEFINED,		/* 16c */
	TPM_UNDEFINED,		/* 16d */
	TPM_UNDEFINED,		/* 16e */
	TPM_UNDEFINED,		/* 16f */
	TPM_UNDEFINED,		/* 170 */
	TPM_UNDEFINED,		/* 171 */
	TPM_UNDEFINED,		/* 172 */
	TPM_UNDEFINED,		/* 173 */
	TPM_UNDEFINED,		/* 174 */
	TPM_UNDEFINED,		/* 175 */
	TPM_UNDEFINED,		/* 176 */
	TPM_LONG,		/* 177 */
	TPM_UNDEFINED,		/* 178 */
	TPM_UNDEFINED,		/* 179 */
	TPM_MEDIUM,		/* 17a */
	TPM_LONG,		/* 17b */
	TPM_UNDEFINED,		/* 17c */
	TPM_UNDEFINED,		/* 17d */
	TPM_UNDEFINED,		/* 17e */
	TPM_UNDEFINED,		/* 17f */
	TPM_UNDEFINED,		/* 180 */
	TPM_UNDEFINED,		/* 181 */
	TPM_MEDIUM,		/* 182 */
	TPM_UNDEFINED,		/* 183 */
	TPM_UNDEFINED,		/* 184 */
	TPM_MEDIUM,		/* 185 */
	TPM_MEDIUM,		/* 186 */
	TPM_UNDEFINED,		/* 187 */
	TPM_UNDEFINED,		/* 188 */
	TPM_UNDEFINED,		/* 189 */
	TPM_UNDEFINED,		/* 18a */
	TPM_UNDEFINED,		/* 18b */
	TPM_UNDEFINED,		/* 18c */
	TPM_UNDEFINED,		/* 18d */
	TPM_UNDEFINED,		/* 18e */
	TPM_UNDEFINED		/* 18f */
};

#define TPM2_PCR_READ_IN_SIZE \
	(sizeof(struct tpm_input_header) + \
	 sizeof(struct tpm2_pcr_read_in))

static const struct tpm_input_header tpm2_pcrread_header = {
	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
	.length = cpu_to_be32(TPM2_PCR_READ_IN_SIZE),
	.ordinal = cpu_to_be32(TPM2_CC_PCR_READ)
};

/**
 * tpm2_pcr_read() - read a PCR value
 * @chip:	TPM chip to use.
 * @pcr_idx:	index of the PCR to read.
 * @ref_buf:	buffer to store the resulting hash,
 *
 * 0 is returned when the operation is successful. If a negative number is
 * returned it remarks a POSIX error code. If a positive number is returned
 * it remarks a TPM error.
 */
int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
{
	int rc;
	struct tpm2_cmd cmd;
	u8 *buf;

	if (pcr_idx >= TPM2_PLATFORM_PCR)
		return -EINVAL;

	cmd.header.in = tpm2_pcrread_header;
	cmd.params.pcrread_in.pcr_selects_cnt = cpu_to_be32(1);
	cmd.params.pcrread_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
	cmd.params.pcrread_in.pcr_select_size = TPM2_PCR_SELECT_MIN;

	memset(cmd.params.pcrread_in.pcr_select, 0,
	       sizeof(cmd.params.pcrread_in.pcr_select));
	cmd.params.pcrread_in.pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);

	rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
			      "attempting to read a pcr value");
	if (rc == 0) {
		buf = cmd.params.pcrread_out.digest;
		memcpy(res_buf, buf, TPM_DIGEST_SIZE);
	}

	return rc;
}

#define TPM2_GET_PCREXTEND_IN_SIZE \
	(sizeof(struct tpm_input_header) + \
	 sizeof(struct tpm2_pcr_extend_in))

static const struct tpm_input_header tpm2_pcrextend_header = {
	.tag = cpu_to_be16(TPM2_ST_SESSIONS),
	.length = cpu_to_be32(TPM2_GET_PCREXTEND_IN_SIZE),
	.ordinal = cpu_to_be32(TPM2_CC_PCR_EXTEND)
};

/**
 * tpm2_pcr_extend() - extend a PCR value
 * @chip:	TPM chip to use.
 * @pcr_idx:	index of the PCR.
 * @hash:	hash value to use for the extend operation.
 *
 * 0 is returned when the operation is successful. If a negative number is
 * returned it remarks a POSIX error code. If a positive number is returned
 * it remarks a TPM error.
 */
int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash)
{
	struct tpm2_cmd cmd;
	int rc;

	cmd.header.in = tpm2_pcrextend_header;
	cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
	cmd.params.pcrextend_in.auth_area_size =
		cpu_to_be32(sizeof(struct tpm2_null_auth_area));
	cmd.params.pcrextend_in.auth_area.handle =
		cpu_to_be32(TPM2_RS_PW);
	cmd.params.pcrextend_in.auth_area.nonce_size = 0;
	cmd.params.pcrextend_in.auth_area.attributes = 0;
	cmd.params.pcrextend_in.auth_area.auth_size = 0;
	cmd.params.pcrextend_in.digest_cnt = cpu_to_be32(1);
	cmd.params.pcrextend_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
	memcpy(cmd.params.pcrextend_in.digest, hash, TPM_DIGEST_SIZE);

	rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
			      "attempting extend a PCR value");

	return rc;
}

#define TPM2_GETRANDOM_IN_SIZE \
	(sizeof(struct tpm_input_header) + \
	 sizeof(struct tpm2_get_random_in))

static const struct tpm_input_header tpm2_getrandom_header = {
	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
	.length = cpu_to_be32(TPM2_GETRANDOM_IN_SIZE),
	.ordinal = cpu_to_be32(TPM2_CC_GET_RANDOM)
};

/**
 * tpm2_get_random() - get random bytes from the TPM RNG
 * @chip: TPM chip to use
 * @out: destination buffer for the random bytes
 * @max: the max number of bytes to write to @out
 *
 * 0 is returned when the operation is successful. If a negative number is
 * returned it remarks a POSIX error code. If a positive number is returned
 * it remarks a TPM error.
 */
int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
{
	struct tpm2_cmd cmd;
	u32 recd;
	u32 num_bytes;
	int err;
	int total = 0;
	int retries = 5;
	u8 *dest = out;

	num_bytes = min_t(u32, max, sizeof(cmd.params.getrandom_out.buffer));

	if (!out || !num_bytes ||
	    max > sizeof(cmd.params.getrandom_out.buffer))
		return -EINVAL;

	do {
		cmd.header.in = tpm2_getrandom_header;
		cmd.params.getrandom_in.size = cpu_to_be16(num_bytes);

		err = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
				       "attempting get random");
		if (err)
			break;

		recd = min_t(u32, be16_to_cpu(cmd.params.getrandom_out.size),
			     num_bytes);
		memcpy(dest, cmd.params.getrandom_out.buffer, recd);

		dest += recd;
		total += recd;
		num_bytes -= recd;
	} while (retries-- && total < max);

	return total ? total : -EIO;
}

#define TPM2_GET_TPM_PT_IN_SIZE \
	(sizeof(struct tpm_input_header) + \
	 sizeof(struct tpm2_get_tpm_pt_in))

static const struct tpm_input_header tpm2_get_tpm_pt_header = {
	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
	.length = cpu_to_be32(TPM2_GET_TPM_PT_IN_SIZE),
	.ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
};

/**
 * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
 * @chip:		TPM chip to use.
 * @property_id:	property ID.
 * @value:		output variable.
 * @desc:		passed to tpm_transmit_cmd()
 *
 * 0 is returned when the operation is successful. If a negative number is
 * returned it remarks a POSIX error code. If a positive number is returned
 * it remarks a TPM error.
 */
ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
			const char *desc)
{
	struct tpm2_cmd cmd;
	int rc;

	cmd.header.in = tpm2_get_tpm_pt_header;
	cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
	cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(property_id);
	cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);

	rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), desc);
	if (!rc)
		*value = cmd.params.get_tpm_pt_out.value;

	return rc;
}

#define TPM2_STARTUP_IN_SIZE \
	(sizeof(struct tpm_input_header) + \
	 sizeof(struct tpm2_startup_in))

static const struct tpm_input_header tpm2_startup_header = {
	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
	.length = cpu_to_be32(TPM2_STARTUP_IN_SIZE),
	.ordinal = cpu_to_be32(TPM2_CC_STARTUP)
};

/**
 * tpm2_startup() - send startup command to the TPM chip
 * @chip:		TPM chip to use.
 * @startup_type	startup type. The value is either
 *			TPM_SU_CLEAR or TPM_SU_STATE.
 *
 * 0 is returned when the operation is successful. If a negative number is
 * returned it remarks a POSIX error code. If a positive number is returned
 * it remarks a TPM error.
 */
int tpm2_startup(struct tpm_chip *chip, u16 startup_type)
{
	struct tpm2_cmd cmd;

	cmd.header.in = tpm2_startup_header;

	cmd.params.startup_in.startup_type = cpu_to_be16(startup_type);
	return tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
				"attempting to start the TPM");
}
EXPORT_SYMBOL_GPL(tpm2_startup);

#define TPM2_SHUTDOWN_IN_SIZE \
	(sizeof(struct tpm_input_header) + \
	 sizeof(struct tpm2_startup_in))

static const struct tpm_input_header tpm2_shutdown_header = {
	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
	.length = cpu_to_be32(TPM2_SHUTDOWN_IN_SIZE),
	.ordinal = cpu_to_be32(TPM2_CC_SHUTDOWN)
};

/**
 * tpm2_shutdown() - send shutdown command to the TPM chip
 * @chip:		TPM chip to use.
 * @shutdown_type	shutdown type. The value is either
 *			TPM_SU_CLEAR or TPM_SU_STATE.
 */
void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
{
	struct tpm2_cmd cmd;
	int rc;

	cmd.header.in = tpm2_shutdown_header;
	cmd.params.startup_in.startup_type = cpu_to_be16(shutdown_type);

	rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), "stopping the TPM");

	/* In places where shutdown command is sent there's no much we can do
	 * except print the error code on a system failure.
	 */
	if (rc < 0)
		dev_warn(chip->pdev, "transmit returned %d while stopping the TPM",
			 rc);
}
EXPORT_SYMBOL_GPL(tpm2_shutdown);

/*
 * tpm2_calc_ordinal_duration() - maximum duration for a command
 * @chip:	TPM chip to use.
 * @ordinal:	command code number.
 *
 * 0 is returned when the operation is successful. If a negative number is
 * returned it remarks a POSIX error code. If a positive number is returned
 * it remarks a TPM error.
 */
unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
{
	int index = TPM_UNDEFINED;
	int duration = 0;

	if (ordinal >= TPM2_CC_FIRST && ordinal <= TPM2_CC_LAST)
		index = tpm2_ordinal_duration[ordinal - TPM2_CC_FIRST];

	if (index != TPM_UNDEFINED)
		duration = chip->vendor.duration[index];

	if (duration <= 0)
		duration = 2 * 60 * HZ;

	return duration;
}
EXPORT_SYMBOL_GPL(tpm2_calc_ordinal_duration);

#define TPM2_SELF_TEST_IN_SIZE \
	(sizeof(struct tpm_input_header) + \
	 sizeof(struct tpm2_self_test_in))

static const struct tpm_input_header tpm2_selftest_header = {
	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
	.length = cpu_to_be32(TPM2_SELF_TEST_IN_SIZE),
	.ordinal = cpu_to_be32(TPM2_CC_SELF_TEST)
};

/**
 * tpm2_continue_selftest() - start a self test
 * @chip: TPM chip to use
 * @full: test all commands instead of testing only those that were not
 *        previously tested.
 *
 * 0 is returned when the operation is successful. If a negative number is
 * returned it remarks a POSIX error code. If a positive number is returned
 * it remarks a TPM error.
 */
static int tpm2_start_selftest(struct tpm_chip *chip, bool full)
{
	int rc;
	struct tpm2_cmd cmd;

	cmd.header.in = tpm2_selftest_header;
	cmd.params.selftest_in.full_test = full;

	rc = tpm_transmit_cmd(chip, &cmd, TPM2_SELF_TEST_IN_SIZE,
			      "continue selftest");

	/* At least some prototype chips seem to give RC_TESTING error
	 * immediately. This is a workaround for that.
	 */
	if (rc == TPM2_RC_TESTING) {
		dev_warn(chip->pdev, "Got RC_TESTING, ignoring\n");
		rc = 0;
	}

	return rc;
}

/**
 * tpm2_do_selftest() - run a full self test
 * @chip: TPM chip to use
 *
 * During the self test TPM2 commands return with the error code RC_TESTING.
 * Waiting is done by issuing PCR read until it executes successfully.
 *
 * 0 is returned when the operation is successful. If a negative number is
 * returned it remarks a POSIX error code. If a positive number is returned
 * it remarks a TPM error.
 */
int tpm2_do_selftest(struct tpm_chip *chip)
{
	int rc;
	unsigned int loops;
	unsigned int delay_msec = 100;
	unsigned long duration;
	struct tpm2_cmd cmd;
	int i;

	duration = tpm2_calc_ordinal_duration(chip, TPM2_CC_SELF_TEST);

	loops = jiffies_to_msecs(duration) / delay_msec;

	rc = tpm2_start_selftest(chip, true);
	if (rc)
		return rc;

	for (i = 0; i < loops; i++) {
		/* Attempt to read a PCR value */
		cmd.header.in = tpm2_pcrread_header;
		cmd.params.pcrread_in.pcr_selects_cnt = cpu_to_be32(1);
		cmd.params.pcrread_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
		cmd.params.pcrread_in.pcr_select_size = TPM2_PCR_SELECT_MIN;
		cmd.params.pcrread_in.pcr_select[0] = 0x01;
		cmd.params.pcrread_in.pcr_select[1] = 0x00;
		cmd.params.pcrread_in.pcr_select[2] = 0x00;

		rc = tpm_transmit_cmd(chip, (u8 *) &cmd, sizeof(cmd), NULL);
		if (rc < 0)
			break;

		rc = be32_to_cpu(cmd.header.out.return_code);
		if (rc != TPM2_RC_TESTING)
			break;

		msleep(delay_msec);
	}

	return rc;
}
EXPORT_SYMBOL_GPL(tpm2_do_selftest);

/**
 * tpm2_gen_interrupt() - generate an interrupt
 * @chip: TPM chip to use
 *
 * 0 is returned when the operation is successful. If a negative number is
 * returned it remarks a POSIX error code. If a positive number is returned
 * it remarks a TPM error.
 */
int tpm2_gen_interrupt(struct tpm_chip *chip)
{
	u32 dummy;

	return tpm2_get_tpm_pt(chip, 0x100, &dummy,
			       "attempting to generate an interrupt");
}
EXPORT_SYMBOL_GPL(tpm2_gen_interrupt);

/**
 * tpm2_probe() - probe TPM 2.0
 * @chip: TPM chip to use
 *
 * Send idempotent TPM 2.0 command and see whether TPM 2.0 chip replied based on
 * the reply tag.
 */
int tpm2_probe(struct tpm_chip *chip)
{
	struct tpm2_cmd cmd;
	int rc;

	cmd.header.in = tpm2_get_tpm_pt_header;
	cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
	cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(0x100);
	cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);

	rc = tpm_transmit(chip, (const char *) &cmd, sizeof(cmd));
	if (rc <  0)
		return rc;
	else if (rc < TPM_HEADER_SIZE)
		return -EFAULT;

	if (be16_to_cpu(cmd.header.out.tag) == TPM2_ST_NO_SESSIONS)
		chip->flags |= TPM_CHIP_FLAG_TPM2;

	return 0;
}
EXPORT_SYMBOL_GPL(tpm2_probe);