xref: /linux/drivers/char/tpm/tpm2-cmd.c (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
1 /*
2  * Copyright (C) 2014, 2015 Intel Corporation
3  *
4  * Authors:
5  * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
6  *
7  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
8  *
9  * This file contains TPM2 protocol implementations of the commands
10  * used by the kernel internally.
11  *
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License
14  * as published by the Free Software Foundation; version 2
15  * of the License.
16  */
17 
18 #include "tpm.h"
19 #include <crypto/hash_info.h>
20 #include <keys/trusted-type.h>
21 
22 enum tpm2_object_attributes {
23 	TPM2_OA_USER_WITH_AUTH		= BIT(6),
24 };
25 
26 enum tpm2_session_attributes {
27 	TPM2_SA_CONTINUE_SESSION	= BIT(0),
28 };
29 
30 struct tpm2_startup_in {
31 	__be16	startup_type;
32 } __packed;
33 
34 struct tpm2_self_test_in {
35 	u8	full_test;
36 } __packed;
37 
38 struct tpm2_pcr_read_in {
39 	__be32	pcr_selects_cnt;
40 	__be16	hash_alg;
41 	u8	pcr_select_size;
42 	u8	pcr_select[TPM2_PCR_SELECT_MIN];
43 } __packed;
44 
45 struct tpm2_pcr_read_out {
46 	__be32	update_cnt;
47 	__be32	pcr_selects_cnt;
48 	__be16	hash_alg;
49 	u8	pcr_select_size;
50 	u8	pcr_select[TPM2_PCR_SELECT_MIN];
51 	__be32	digests_cnt;
52 	__be16	digest_size;
53 	u8	digest[TPM_DIGEST_SIZE];
54 } __packed;
55 
56 struct tpm2_get_tpm_pt_in {
57 	__be32	cap_id;
58 	__be32	property_id;
59 	__be32	property_cnt;
60 } __packed;
61 
62 struct tpm2_get_tpm_pt_out {
63 	u8	more_data;
64 	__be32	subcap_id;
65 	__be32	property_cnt;
66 	__be32	property_id;
67 	__be32	value;
68 } __packed;
69 
70 struct tpm2_get_random_in {
71 	__be16	size;
72 } __packed;
73 
74 struct tpm2_get_random_out {
75 	__be16	size;
76 	u8	buffer[TPM_MAX_RNG_DATA];
77 } __packed;
78 
79 union tpm2_cmd_params {
80 	struct	tpm2_startup_in		startup_in;
81 	struct	tpm2_self_test_in	selftest_in;
82 	struct	tpm2_pcr_read_in	pcrread_in;
83 	struct	tpm2_pcr_read_out	pcrread_out;
84 	struct	tpm2_get_tpm_pt_in	get_tpm_pt_in;
85 	struct	tpm2_get_tpm_pt_out	get_tpm_pt_out;
86 	struct	tpm2_get_random_in	getrandom_in;
87 	struct	tpm2_get_random_out	getrandom_out;
88 };
89 
90 struct tpm2_cmd {
91 	tpm_cmd_header		header;
92 	union tpm2_cmd_params	params;
93 } __packed;
94 
95 struct tpm2_hash {
96 	unsigned int crypto_id;
97 	unsigned int tpm_id;
98 };
99 
100 static struct tpm2_hash tpm2_hash_map[] = {
101 	{HASH_ALGO_SHA1, TPM2_ALG_SHA1},
102 	{HASH_ALGO_SHA256, TPM2_ALG_SHA256},
103 	{HASH_ALGO_SHA384, TPM2_ALG_SHA384},
104 	{HASH_ALGO_SHA512, TPM2_ALG_SHA512},
105 	{HASH_ALGO_SM3_256, TPM2_ALG_SM3_256},
106 };
107 
108 /*
109  * Array with one entry per ordinal defining the maximum amount
110  * of time the chip could take to return the result. The values
111  * of the SHORT, MEDIUM, and LONG durations are taken from the
112  * PC Client Profile (PTP) specification.
113  */
114 static const u8 tpm2_ordinal_duration[TPM2_CC_LAST - TPM2_CC_FIRST + 1] = {
115 	TPM_UNDEFINED,		/* 11F */
116 	TPM_UNDEFINED,		/* 120 */
117 	TPM_LONG,		/* 121 */
118 	TPM_UNDEFINED,		/* 122 */
119 	TPM_UNDEFINED,		/* 123 */
120 	TPM_UNDEFINED,		/* 124 */
121 	TPM_UNDEFINED,		/* 125 */
122 	TPM_UNDEFINED,		/* 126 */
123 	TPM_UNDEFINED,		/* 127 */
124 	TPM_UNDEFINED,		/* 128 */
125 	TPM_LONG,		/* 129 */
126 	TPM_UNDEFINED,		/* 12a */
127 	TPM_UNDEFINED,		/* 12b */
128 	TPM_UNDEFINED,		/* 12c */
129 	TPM_UNDEFINED,		/* 12d */
130 	TPM_UNDEFINED,		/* 12e */
131 	TPM_UNDEFINED,		/* 12f */
132 	TPM_UNDEFINED,		/* 130 */
133 	TPM_UNDEFINED,		/* 131 */
134 	TPM_UNDEFINED,		/* 132 */
135 	TPM_UNDEFINED,		/* 133 */
136 	TPM_UNDEFINED,		/* 134 */
137 	TPM_UNDEFINED,		/* 135 */
138 	TPM_UNDEFINED,		/* 136 */
139 	TPM_UNDEFINED,		/* 137 */
140 	TPM_UNDEFINED,		/* 138 */
141 	TPM_UNDEFINED,		/* 139 */
142 	TPM_UNDEFINED,		/* 13a */
143 	TPM_UNDEFINED,		/* 13b */
144 	TPM_UNDEFINED,		/* 13c */
145 	TPM_UNDEFINED,		/* 13d */
146 	TPM_MEDIUM,		/* 13e */
147 	TPM_UNDEFINED,		/* 13f */
148 	TPM_UNDEFINED,		/* 140 */
149 	TPM_UNDEFINED,		/* 141 */
150 	TPM_UNDEFINED,		/* 142 */
151 	TPM_LONG,		/* 143 */
152 	TPM_MEDIUM,		/* 144 */
153 	TPM_UNDEFINED,		/* 145 */
154 	TPM_UNDEFINED,		/* 146 */
155 	TPM_UNDEFINED,		/* 147 */
156 	TPM_UNDEFINED,		/* 148 */
157 	TPM_UNDEFINED,		/* 149 */
158 	TPM_UNDEFINED,		/* 14a */
159 	TPM_UNDEFINED,		/* 14b */
160 	TPM_UNDEFINED,		/* 14c */
161 	TPM_UNDEFINED,		/* 14d */
162 	TPM_LONG,		/* 14e */
163 	TPM_UNDEFINED,		/* 14f */
164 	TPM_UNDEFINED,		/* 150 */
165 	TPM_UNDEFINED,		/* 151 */
166 	TPM_UNDEFINED,		/* 152 */
167 	TPM_UNDEFINED,		/* 153 */
168 	TPM_UNDEFINED,		/* 154 */
169 	TPM_UNDEFINED,		/* 155 */
170 	TPM_UNDEFINED,		/* 156 */
171 	TPM_UNDEFINED,		/* 157 */
172 	TPM_UNDEFINED,		/* 158 */
173 	TPM_UNDEFINED,		/* 159 */
174 	TPM_UNDEFINED,		/* 15a */
175 	TPM_UNDEFINED,		/* 15b */
176 	TPM_MEDIUM,		/* 15c */
177 	TPM_UNDEFINED,		/* 15d */
178 	TPM_UNDEFINED,		/* 15e */
179 	TPM_UNDEFINED,		/* 15f */
180 	TPM_UNDEFINED,		/* 160 */
181 	TPM_UNDEFINED,		/* 161 */
182 	TPM_UNDEFINED,		/* 162 */
183 	TPM_UNDEFINED,		/* 163 */
184 	TPM_UNDEFINED,		/* 164 */
185 	TPM_UNDEFINED,		/* 165 */
186 	TPM_UNDEFINED,		/* 166 */
187 	TPM_UNDEFINED,		/* 167 */
188 	TPM_UNDEFINED,		/* 168 */
189 	TPM_UNDEFINED,		/* 169 */
190 	TPM_UNDEFINED,		/* 16a */
191 	TPM_UNDEFINED,		/* 16b */
192 	TPM_UNDEFINED,		/* 16c */
193 	TPM_UNDEFINED,		/* 16d */
194 	TPM_UNDEFINED,		/* 16e */
195 	TPM_UNDEFINED,		/* 16f */
196 	TPM_UNDEFINED,		/* 170 */
197 	TPM_UNDEFINED,		/* 171 */
198 	TPM_UNDEFINED,		/* 172 */
199 	TPM_UNDEFINED,		/* 173 */
200 	TPM_UNDEFINED,		/* 174 */
201 	TPM_UNDEFINED,		/* 175 */
202 	TPM_UNDEFINED,		/* 176 */
203 	TPM_LONG,		/* 177 */
204 	TPM_UNDEFINED,		/* 178 */
205 	TPM_UNDEFINED,		/* 179 */
206 	TPM_MEDIUM,		/* 17a */
207 	TPM_LONG,		/* 17b */
208 	TPM_UNDEFINED,		/* 17c */
209 	TPM_UNDEFINED,		/* 17d */
210 	TPM_UNDEFINED,		/* 17e */
211 	TPM_UNDEFINED,		/* 17f */
212 	TPM_UNDEFINED,		/* 180 */
213 	TPM_UNDEFINED,		/* 181 */
214 	TPM_MEDIUM,		/* 182 */
215 	TPM_UNDEFINED,		/* 183 */
216 	TPM_UNDEFINED,		/* 184 */
217 	TPM_MEDIUM,		/* 185 */
218 	TPM_MEDIUM,		/* 186 */
219 	TPM_UNDEFINED,		/* 187 */
220 	TPM_UNDEFINED,		/* 188 */
221 	TPM_UNDEFINED,		/* 189 */
222 	TPM_UNDEFINED,		/* 18a */
223 	TPM_UNDEFINED,		/* 18b */
224 	TPM_UNDEFINED,		/* 18c */
225 	TPM_UNDEFINED,		/* 18d */
226 	TPM_UNDEFINED,		/* 18e */
227 	TPM_UNDEFINED		/* 18f */
228 };
229 
230 #define TPM2_PCR_READ_IN_SIZE \
231 	(sizeof(struct tpm_input_header) + \
232 	 sizeof(struct tpm2_pcr_read_in))
233 
234 #define TPM2_PCR_READ_RESP_BODY_SIZE \
235 	 sizeof(struct tpm2_pcr_read_out)
236 
237 static const struct tpm_input_header tpm2_pcrread_header = {
238 	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
239 	.length = cpu_to_be32(TPM2_PCR_READ_IN_SIZE),
240 	.ordinal = cpu_to_be32(TPM2_CC_PCR_READ)
241 };
242 
243 /**
244  * tpm2_pcr_read() - read a PCR value
245  * @chip:	TPM chip to use.
246  * @pcr_idx:	index of the PCR to read.
247  * @res_buf:	buffer to store the resulting hash.
248  *
249  * Return: Same as with tpm_transmit_cmd.
250  */
251 int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
252 {
253 	int rc;
254 	struct tpm2_cmd cmd;
255 	u8 *buf;
256 
257 	if (pcr_idx >= TPM2_PLATFORM_PCR)
258 		return -EINVAL;
259 
260 	cmd.header.in = tpm2_pcrread_header;
261 	cmd.params.pcrread_in.pcr_selects_cnt = cpu_to_be32(1);
262 	cmd.params.pcrread_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
263 	cmd.params.pcrread_in.pcr_select_size = TPM2_PCR_SELECT_MIN;
264 
265 	memset(cmd.params.pcrread_in.pcr_select, 0,
266 	       sizeof(cmd.params.pcrread_in.pcr_select));
267 	cmd.params.pcrread_in.pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
268 
269 	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd),
270 			      TPM2_PCR_READ_RESP_BODY_SIZE,
271 			      0, "attempting to read a pcr value");
272 	if (rc == 0) {
273 		buf = cmd.params.pcrread_out.digest;
274 		memcpy(res_buf, buf, TPM_DIGEST_SIZE);
275 	}
276 
277 	return rc;
278 }
279 
280 struct tpm2_null_auth_area {
281 	__be32  handle;
282 	__be16  nonce_size;
283 	u8  attributes;
284 	__be16  auth_size;
285 } __packed;
286 
287 /**
288  * tpm2_pcr_extend() - extend a PCR value
289  *
290  * @chip:	TPM chip to use.
291  * @pcr_idx:	index of the PCR.
292  * @count:	number of digests passed.
293  * @digests:	list of pcr banks and corresponding digest values to extend.
294  *
295  * Return: Same as with tpm_transmit_cmd.
296  */
297 int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, u32 count,
298 		    struct tpm2_digest *digests)
299 {
300 	struct tpm_buf buf;
301 	struct tpm2_null_auth_area auth_area;
302 	int rc;
303 	int i;
304 	int j;
305 
306 	if (count > ARRAY_SIZE(chip->active_banks))
307 		return -EINVAL;
308 
309 	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
310 	if (rc)
311 		return rc;
312 
313 	tpm_buf_append_u32(&buf, pcr_idx);
314 
315 	auth_area.handle = cpu_to_be32(TPM2_RS_PW);
316 	auth_area.nonce_size = 0;
317 	auth_area.attributes = 0;
318 	auth_area.auth_size = 0;
319 
320 	tpm_buf_append_u32(&buf, sizeof(struct tpm2_null_auth_area));
321 	tpm_buf_append(&buf, (const unsigned char *)&auth_area,
322 		       sizeof(auth_area));
323 	tpm_buf_append_u32(&buf, count);
324 
325 	for (i = 0; i < count; i++) {
326 		for (j = 0; j < ARRAY_SIZE(tpm2_hash_map); j++) {
327 			if (digests[i].alg_id != tpm2_hash_map[j].tpm_id)
328 				continue;
329 			tpm_buf_append_u16(&buf, digests[i].alg_id);
330 			tpm_buf_append(&buf, (const unsigned char
331 					      *)&digests[i].digest,
332 			       hash_digest_size[tpm2_hash_map[j].crypto_id]);
333 		}
334 	}
335 
336 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
337 			      "attempting extend a PCR value");
338 
339 	tpm_buf_destroy(&buf);
340 
341 	return rc;
342 }
343 
344 
345 #define TPM2_GETRANDOM_IN_SIZE \
346 	(sizeof(struct tpm_input_header) + \
347 	 sizeof(struct tpm2_get_random_in))
348 
349 static const struct tpm_input_header tpm2_getrandom_header = {
350 	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
351 	.length = cpu_to_be32(TPM2_GETRANDOM_IN_SIZE),
352 	.ordinal = cpu_to_be32(TPM2_CC_GET_RANDOM)
353 };
354 
355 /**
356  * tpm2_get_random() - get random bytes from the TPM RNG
357  *
358  * @chip: TPM chip to use
359  * @out: destination buffer for the random bytes
360  * @max: the max number of bytes to write to @out
361  *
362  * Return:
363  *    Size of the output buffer, or -EIO on error.
364  */
365 int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
366 {
367 	struct tpm2_cmd cmd;
368 	u32 recd, rlength;
369 	u32 num_bytes;
370 	int err;
371 	int total = 0;
372 	int retries = 5;
373 	u8 *dest = out;
374 
375 	num_bytes = min_t(u32, max, sizeof(cmd.params.getrandom_out.buffer));
376 
377 	if (!out || !num_bytes ||
378 	    max > sizeof(cmd.params.getrandom_out.buffer))
379 		return -EINVAL;
380 
381 	do {
382 		cmd.header.in = tpm2_getrandom_header;
383 		cmd.params.getrandom_in.size = cpu_to_be16(num_bytes);
384 
385 		err = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd),
386 				       offsetof(struct tpm2_get_random_out,
387 						buffer),
388 				       0, "attempting get random");
389 		if (err)
390 			break;
391 
392 		recd = min_t(u32, be16_to_cpu(cmd.params.getrandom_out.size),
393 			     num_bytes);
394 		rlength = be32_to_cpu(cmd.header.out.length);
395 		if (rlength < offsetof(struct tpm2_get_random_out, buffer) +
396 			      recd)
397 			return -EFAULT;
398 		memcpy(dest, cmd.params.getrandom_out.buffer, recd);
399 
400 		dest += recd;
401 		total += recd;
402 		num_bytes -= recd;
403 	} while (retries-- && total < max);
404 
405 	return total ? total : -EIO;
406 }
407 
408 #define TPM2_GET_TPM_PT_IN_SIZE \
409 	(sizeof(struct tpm_input_header) + \
410 	 sizeof(struct tpm2_get_tpm_pt_in))
411 
412 #define TPM2_GET_TPM_PT_OUT_BODY_SIZE \
413 	 sizeof(struct tpm2_get_tpm_pt_out)
414 
415 static const struct tpm_input_header tpm2_get_tpm_pt_header = {
416 	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
417 	.length = cpu_to_be32(TPM2_GET_TPM_PT_IN_SIZE),
418 	.ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
419 };
420 
421 /**
422  * tpm2_flush_context_cmd() - execute a TPM2_FlushContext command
423  * @chip: TPM chip to use
424  * @payload: the key data in clear and encrypted form
425  * @options: authentication values and other options
426  *
427  * Return: same as with tpm_transmit_cmd
428  */
429 void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
430 			    unsigned int flags)
431 {
432 	struct tpm_buf buf;
433 	int rc;
434 
435 	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
436 	if (rc) {
437 		dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n",
438 			 handle);
439 		return;
440 	}
441 
442 	tpm_buf_append_u32(&buf, handle);
443 
444 	(void) tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, flags,
445 				"flushing context");
446 
447 	tpm_buf_destroy(&buf);
448 }
449 
450 /**
451  * tpm_buf_append_auth() - append TPMS_AUTH_COMMAND to the buffer.
452  *
453  * @buf: an allocated tpm_buf instance
454  * @session_handle: session handle
455  * @nonce: the session nonce, may be NULL if not used
456  * @nonce_len: the session nonce length, may be 0 if not used
457  * @attributes: the session attributes
458  * @hmac: the session HMAC or password, may be NULL if not used
459  * @hmac_len: the session HMAC or password length, maybe 0 if not used
460  */
461 static void tpm2_buf_append_auth(struct tpm_buf *buf, u32 session_handle,
462 				 const u8 *nonce, u16 nonce_len,
463 				 u8 attributes,
464 				 const u8 *hmac, u16 hmac_len)
465 {
466 	tpm_buf_append_u32(buf, 9 + nonce_len + hmac_len);
467 	tpm_buf_append_u32(buf, session_handle);
468 	tpm_buf_append_u16(buf, nonce_len);
469 
470 	if (nonce && nonce_len)
471 		tpm_buf_append(buf, nonce, nonce_len);
472 
473 	tpm_buf_append_u8(buf, attributes);
474 	tpm_buf_append_u16(buf, hmac_len);
475 
476 	if (hmac && hmac_len)
477 		tpm_buf_append(buf, hmac, hmac_len);
478 }
479 
480 /**
481  * tpm2_seal_trusted() - seal the payload of a trusted key
482  *
483  * @chip: TPM chip to use
484  * @payload: the key data in clear and encrypted form
485  * @options: authentication values and other options
486  *
487  * Return: < 0 on error and 0 on success.
488  */
489 int tpm2_seal_trusted(struct tpm_chip *chip,
490 		      struct trusted_key_payload *payload,
491 		      struct trusted_key_options *options)
492 {
493 	unsigned int blob_len;
494 	struct tpm_buf buf;
495 	u32 hash, rlength;
496 	int i;
497 	int rc;
498 
499 	for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {
500 		if (options->hash == tpm2_hash_map[i].crypto_id) {
501 			hash = tpm2_hash_map[i].tpm_id;
502 			break;
503 		}
504 	}
505 
506 	if (i == ARRAY_SIZE(tpm2_hash_map))
507 		return -EINVAL;
508 
509 	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
510 	if (rc)
511 		return rc;
512 
513 	tpm_buf_append_u32(&buf, options->keyhandle);
514 	tpm2_buf_append_auth(&buf, TPM2_RS_PW,
515 			     NULL /* nonce */, 0,
516 			     0 /* session_attributes */,
517 			     options->keyauth /* hmac */,
518 			     TPM_DIGEST_SIZE);
519 
520 	/* sensitive */
521 	tpm_buf_append_u16(&buf, 4 + TPM_DIGEST_SIZE + payload->key_len + 1);
522 
523 	tpm_buf_append_u16(&buf, TPM_DIGEST_SIZE);
524 	tpm_buf_append(&buf, options->blobauth, TPM_DIGEST_SIZE);
525 	tpm_buf_append_u16(&buf, payload->key_len + 1);
526 	tpm_buf_append(&buf, payload->key, payload->key_len);
527 	tpm_buf_append_u8(&buf, payload->migratable);
528 
529 	/* public */
530 	tpm_buf_append_u16(&buf, 14 + options->policydigest_len);
531 	tpm_buf_append_u16(&buf, TPM2_ALG_KEYEDHASH);
532 	tpm_buf_append_u16(&buf, hash);
533 
534 	/* policy */
535 	if (options->policydigest_len) {
536 		tpm_buf_append_u32(&buf, 0);
537 		tpm_buf_append_u16(&buf, options->policydigest_len);
538 		tpm_buf_append(&buf, options->policydigest,
539 			       options->policydigest_len);
540 	} else {
541 		tpm_buf_append_u32(&buf, TPM2_OA_USER_WITH_AUTH);
542 		tpm_buf_append_u16(&buf, 0);
543 	}
544 
545 	/* public parameters */
546 	tpm_buf_append_u16(&buf, TPM2_ALG_NULL);
547 	tpm_buf_append_u16(&buf, 0);
548 
549 	/* outside info */
550 	tpm_buf_append_u16(&buf, 0);
551 
552 	/* creation PCR */
553 	tpm_buf_append_u32(&buf, 0);
554 
555 	if (buf.flags & TPM_BUF_OVERFLOW) {
556 		rc = -E2BIG;
557 		goto out;
558 	}
559 
560 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 4, 0,
561 			      "sealing data");
562 	if (rc)
563 		goto out;
564 
565 	blob_len = be32_to_cpup((__be32 *) &buf.data[TPM_HEADER_SIZE]);
566 	if (blob_len > MAX_BLOB_SIZE) {
567 		rc = -E2BIG;
568 		goto out;
569 	}
570 	rlength = be32_to_cpu(((struct tpm2_cmd *)&buf)->header.out.length);
571 	if (rlength < TPM_HEADER_SIZE + 4 + blob_len) {
572 		rc = -EFAULT;
573 		goto out;
574 	}
575 
576 	memcpy(payload->blob, &buf.data[TPM_HEADER_SIZE + 4], blob_len);
577 	payload->blob_len = blob_len;
578 
579 out:
580 	tpm_buf_destroy(&buf);
581 
582 	if (rc > 0) {
583 		if (tpm2_rc_value(rc) == TPM2_RC_HASH)
584 			rc = -EINVAL;
585 		else
586 			rc = -EPERM;
587 	}
588 
589 	return rc;
590 }
591 
592 /**
593  * tpm2_load_cmd() - execute a TPM2_Load command
594  *
595  * @chip: TPM chip to use
596  * @payload: the key data in clear and encrypted form
597  * @options: authentication values and other options
598  * @blob_handle: returned blob handle
599  * @flags: tpm transmit flags
600  *
601  * Return: 0 on success.
602  *        -E2BIG on wrong payload size.
603  *        -EPERM on tpm error status.
604  *        < 0 error from tpm_transmit_cmd.
605  */
606 static int tpm2_load_cmd(struct tpm_chip *chip,
607 			 struct trusted_key_payload *payload,
608 			 struct trusted_key_options *options,
609 			 u32 *blob_handle, unsigned int flags)
610 {
611 	struct tpm_buf buf;
612 	unsigned int private_len;
613 	unsigned int public_len;
614 	unsigned int blob_len;
615 	int rc;
616 
617 	private_len = be16_to_cpup((__be16 *) &payload->blob[0]);
618 	if (private_len > (payload->blob_len - 2))
619 		return -E2BIG;
620 
621 	public_len = be16_to_cpup((__be16 *) &payload->blob[2 + private_len]);
622 	blob_len = private_len + public_len + 4;
623 	if (blob_len > payload->blob_len)
624 		return -E2BIG;
625 
626 	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
627 	if (rc)
628 		return rc;
629 
630 	tpm_buf_append_u32(&buf, options->keyhandle);
631 	tpm2_buf_append_auth(&buf, TPM2_RS_PW,
632 			     NULL /* nonce */, 0,
633 			     0 /* session_attributes */,
634 			     options->keyauth /* hmac */,
635 			     TPM_DIGEST_SIZE);
636 
637 	tpm_buf_append(&buf, payload->blob, blob_len);
638 
639 	if (buf.flags & TPM_BUF_OVERFLOW) {
640 		rc = -E2BIG;
641 		goto out;
642 	}
643 
644 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 4, flags,
645 			      "loading blob");
646 	if (!rc)
647 		*blob_handle = be32_to_cpup(
648 			(__be32 *) &buf.data[TPM_HEADER_SIZE]);
649 
650 out:
651 	tpm_buf_destroy(&buf);
652 
653 	if (rc > 0)
654 		rc = -EPERM;
655 
656 	return rc;
657 }
658 
659 /**
660  * tpm2_unseal_cmd() - execute a TPM2_Unload command
661  *
662  * @chip: TPM chip to use
663  * @payload: the key data in clear and encrypted form
664  * @options: authentication values and other options
665  * @blob_handle: blob handle
666  * @flags: tpm_transmit_cmd flags
667  *
668  * Return: 0 on success
669  *         -EPERM on tpm error status
670  *         < 0 error from tpm_transmit_cmd
671  */
672 static int tpm2_unseal_cmd(struct tpm_chip *chip,
673 			   struct trusted_key_payload *payload,
674 			   struct trusted_key_options *options,
675 			   u32 blob_handle, unsigned int flags)
676 {
677 	struct tpm_buf buf;
678 	u16 data_len;
679 	u8 *data;
680 	int rc;
681 	u32 rlength;
682 
683 	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
684 	if (rc)
685 		return rc;
686 
687 	tpm_buf_append_u32(&buf, blob_handle);
688 	tpm2_buf_append_auth(&buf,
689 			     options->policyhandle ?
690 			     options->policyhandle : TPM2_RS_PW,
691 			     NULL /* nonce */, 0,
692 			     TPM2_SA_CONTINUE_SESSION,
693 			     options->blobauth /* hmac */,
694 			     TPM_DIGEST_SIZE);
695 
696 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 6, flags,
697 			      "unsealing");
698 	if (rc > 0)
699 		rc = -EPERM;
700 
701 	if (!rc) {
702 		data_len = be16_to_cpup(
703 			(__be16 *) &buf.data[TPM_HEADER_SIZE + 4]);
704 
705 		rlength = be32_to_cpu(((struct tpm2_cmd *)&buf)
706 					->header.out.length);
707 		if (rlength < TPM_HEADER_SIZE + 6 + data_len) {
708 			rc = -EFAULT;
709 			goto out;
710 		}
711 		data = &buf.data[TPM_HEADER_SIZE + 6];
712 
713 		memcpy(payload->key, data, data_len - 1);
714 		payload->key_len = data_len - 1;
715 		payload->migratable = data[data_len - 1];
716 	}
717 
718 out:
719 	tpm_buf_destroy(&buf);
720 	return rc;
721 }
722 
723 /**
724  * tpm2_unseal_trusted() - unseal the payload of a trusted key
725  *
726  * @chip: TPM chip to use
727  * @payload: the key data in clear and encrypted form
728  * @options: authentication values and other options
729  *
730  * Return: Same as with tpm_transmit_cmd.
731  */
732 int tpm2_unseal_trusted(struct tpm_chip *chip,
733 			struct trusted_key_payload *payload,
734 			struct trusted_key_options *options)
735 {
736 	u32 blob_handle;
737 	int rc;
738 
739 	mutex_lock(&chip->tpm_mutex);
740 	rc = tpm2_load_cmd(chip, payload, options, &blob_handle,
741 			   TPM_TRANSMIT_UNLOCKED);
742 	if (rc)
743 		goto out;
744 
745 	rc = tpm2_unseal_cmd(chip, payload, options, blob_handle,
746 			     TPM_TRANSMIT_UNLOCKED);
747 	tpm2_flush_context_cmd(chip, blob_handle, TPM_TRANSMIT_UNLOCKED);
748 out:
749 	mutex_unlock(&chip->tpm_mutex);
750 	return rc;
751 }
752 
753 /**
754  * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
755  * @chip:		TPM chip to use.
756  * @property_id:	property ID.
757  * @value:		output variable.
758  * @desc:		passed to tpm_transmit_cmd()
759  *
760  * Return: Same as with tpm_transmit_cmd.
761  */
762 ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
763 			const char *desc)
764 {
765 	struct tpm2_cmd cmd;
766 	int rc;
767 
768 	cmd.header.in = tpm2_get_tpm_pt_header;
769 	cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
770 	cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(property_id);
771 	cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
772 
773 	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd),
774 			      TPM2_GET_TPM_PT_OUT_BODY_SIZE, 0, desc);
775 	if (!rc)
776 		*value = be32_to_cpu(cmd.params.get_tpm_pt_out.value);
777 
778 	return rc;
779 }
780 EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
781 
782 #define TPM2_STARTUP_IN_SIZE \
783 	(sizeof(struct tpm_input_header) + \
784 	 sizeof(struct tpm2_startup_in))
785 
786 static const struct tpm_input_header tpm2_startup_header = {
787 	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
788 	.length = cpu_to_be32(TPM2_STARTUP_IN_SIZE),
789 	.ordinal = cpu_to_be32(TPM2_CC_STARTUP)
790 };
791 
792 /**
793  * tpm2_startup() - send startup command to the TPM chip
794  *
795  * @chip:		TPM chip to use.
796  * @startup_type:	startup type. The value is either
797  *			TPM_SU_CLEAR or TPM_SU_STATE.
798  *
799  * Return: Same as with tpm_transmit_cmd.
800  */
801 static int tpm2_startup(struct tpm_chip *chip, u16 startup_type)
802 {
803 	struct tpm2_cmd cmd;
804 
805 	cmd.header.in = tpm2_startup_header;
806 
807 	cmd.params.startup_in.startup_type = cpu_to_be16(startup_type);
808 	return tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0,
809 				"attempting to start the TPM");
810 }
811 
812 #define TPM2_SHUTDOWN_IN_SIZE \
813 	(sizeof(struct tpm_input_header) + \
814 	 sizeof(struct tpm2_startup_in))
815 
816 static const struct tpm_input_header tpm2_shutdown_header = {
817 	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
818 	.length = cpu_to_be32(TPM2_SHUTDOWN_IN_SIZE),
819 	.ordinal = cpu_to_be32(TPM2_CC_SHUTDOWN)
820 };
821 
822 /**
823  * tpm2_shutdown() - send shutdown command to the TPM chip
824  *
825  * @chip:		TPM chip to use.
826  * @shutdown_type:	shutdown type. The value is either
827  *			TPM_SU_CLEAR or TPM_SU_STATE.
828  */
829 void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
830 {
831 	struct tpm2_cmd cmd;
832 	int rc;
833 
834 	cmd.header.in = tpm2_shutdown_header;
835 	cmd.params.startup_in.startup_type = cpu_to_be16(shutdown_type);
836 
837 	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0,
838 			      "stopping the TPM");
839 
840 	/* In places where shutdown command is sent there's no much we can do
841 	 * except print the error code on a system failure.
842 	 */
843 	if (rc < 0)
844 		dev_warn(&chip->dev, "transmit returned %d while stopping the TPM",
845 			 rc);
846 }
847 
848 /*
849  * tpm2_calc_ordinal_duration() - maximum duration for a command
850  *
851  * @chip:	TPM chip to use.
852  * @ordinal:	command code number.
853  *
854  * Return: maximum duration for a command
855  */
856 unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
857 {
858 	int index = TPM_UNDEFINED;
859 	int duration = 0;
860 
861 	if (ordinal >= TPM2_CC_FIRST && ordinal <= TPM2_CC_LAST)
862 		index = tpm2_ordinal_duration[ordinal - TPM2_CC_FIRST];
863 
864 	if (index != TPM_UNDEFINED)
865 		duration = chip->duration[index];
866 
867 	if (duration <= 0)
868 		duration = 2 * 60 * HZ;
869 
870 	return duration;
871 }
872 EXPORT_SYMBOL_GPL(tpm2_calc_ordinal_duration);
873 
874 #define TPM2_SELF_TEST_IN_SIZE \
875 	(sizeof(struct tpm_input_header) + \
876 	 sizeof(struct tpm2_self_test_in))
877 
878 static const struct tpm_input_header tpm2_selftest_header = {
879 	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
880 	.length = cpu_to_be32(TPM2_SELF_TEST_IN_SIZE),
881 	.ordinal = cpu_to_be32(TPM2_CC_SELF_TEST)
882 };
883 
884 /**
885  * tpm2_continue_selftest() - start a self test
886  *
887  * @chip: TPM chip to use
888  * @full: test all commands instead of testing only those that were not
889  *        previously tested.
890  *
891  * Return: Same as with tpm_transmit_cmd with exception of RC_TESTING.
892  */
893 static int tpm2_start_selftest(struct tpm_chip *chip, bool full)
894 {
895 	int rc;
896 	struct tpm2_cmd cmd;
897 
898 	cmd.header.in = tpm2_selftest_header;
899 	cmd.params.selftest_in.full_test = full;
900 
901 	rc = tpm_transmit_cmd(chip, NULL, &cmd, TPM2_SELF_TEST_IN_SIZE, 0, 0,
902 			      "continue selftest");
903 
904 	/* At least some prototype chips seem to give RC_TESTING error
905 	 * immediately. This is a workaround for that.
906 	 */
907 	if (rc == TPM2_RC_TESTING) {
908 		dev_warn(&chip->dev, "Got RC_TESTING, ignoring\n");
909 		rc = 0;
910 	}
911 
912 	return rc;
913 }
914 
915 /**
916  * tpm2_do_selftest() - run a full self test
917  *
918  * @chip: TPM chip to use
919  *
920  * Return: Same as with tpm_transmit_cmd.
921  *
922  * During the self test TPM2 commands return with the error code RC_TESTING.
923  * Waiting is done by issuing PCR read until it executes successfully.
924  */
925 static int tpm2_do_selftest(struct tpm_chip *chip)
926 {
927 	int rc;
928 	unsigned int loops;
929 	unsigned int delay_msec = 100;
930 	unsigned long duration;
931 	struct tpm2_cmd cmd;
932 	int i;
933 
934 	duration = tpm2_calc_ordinal_duration(chip, TPM2_CC_SELF_TEST);
935 
936 	loops = jiffies_to_msecs(duration) / delay_msec;
937 
938 	rc = tpm2_start_selftest(chip, true);
939 	if (rc)
940 		return rc;
941 
942 	for (i = 0; i < loops; i++) {
943 		/* Attempt to read a PCR value */
944 		cmd.header.in = tpm2_pcrread_header;
945 		cmd.params.pcrread_in.pcr_selects_cnt = cpu_to_be32(1);
946 		cmd.params.pcrread_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
947 		cmd.params.pcrread_in.pcr_select_size = TPM2_PCR_SELECT_MIN;
948 		cmd.params.pcrread_in.pcr_select[0] = 0x01;
949 		cmd.params.pcrread_in.pcr_select[1] = 0x00;
950 		cmd.params.pcrread_in.pcr_select[2] = 0x00;
951 
952 		rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0,
953 				      NULL);
954 		if (rc < 0)
955 			break;
956 
957 		rc = be32_to_cpu(cmd.header.out.return_code);
958 		if (rc != TPM2_RC_TESTING)
959 			break;
960 
961 		msleep(delay_msec);
962 	}
963 
964 	return rc;
965 }
966 
967 /**
968  * tpm2_probe() - probe TPM 2.0
969  * @chip: TPM chip to use
970  *
971  * Return: < 0 error and 0 on success.
972  *
973  * Send idempotent TPM 2.0 command and see whether TPM 2.0 chip replied based on
974  * the reply tag.
975  */
976 int tpm2_probe(struct tpm_chip *chip)
977 {
978 	struct tpm2_cmd cmd;
979 	int rc;
980 
981 	cmd.header.in = tpm2_get_tpm_pt_header;
982 	cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
983 	cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(0x100);
984 	cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
985 
986 	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0, NULL);
987 	if (rc <  0)
988 		return rc;
989 
990 	if (be16_to_cpu(cmd.header.out.tag) == TPM2_ST_NO_SESSIONS)
991 		chip->flags |= TPM_CHIP_FLAG_TPM2;
992 
993 	return 0;
994 }
995 EXPORT_SYMBOL_GPL(tpm2_probe);
996 
997 struct tpm2_pcr_selection {
998 	__be16  hash_alg;
999 	u8  size_of_select;
1000 	u8  pcr_select[3];
1001 } __packed;
1002 
1003 static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
1004 {
1005 	struct tpm2_pcr_selection pcr_selection;
1006 	struct tpm_buf buf;
1007 	void *marker;
1008 	void *end;
1009 	void *pcr_select_offset;
1010 	unsigned int count;
1011 	u32 sizeof_pcr_selection;
1012 	u32 rsp_len;
1013 	int rc;
1014 	int i = 0;
1015 
1016 	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
1017 	if (rc)
1018 		return rc;
1019 
1020 	tpm_buf_append_u32(&buf, TPM2_CAP_PCRS);
1021 	tpm_buf_append_u32(&buf, 0);
1022 	tpm_buf_append_u32(&buf, 1);
1023 
1024 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 9, 0,
1025 			      "get tpm pcr allocation");
1026 	if (rc)
1027 		goto out;
1028 
1029 	count = be32_to_cpup(
1030 		(__be32 *)&buf.data[TPM_HEADER_SIZE + 5]);
1031 
1032 	if (count > ARRAY_SIZE(chip->active_banks)) {
1033 		rc = -ENODEV;
1034 		goto out;
1035 	}
1036 
1037 	marker = &buf.data[TPM_HEADER_SIZE + 9];
1038 
1039 	rsp_len = be32_to_cpup((__be32 *)&buf.data[2]);
1040 	end = &buf.data[rsp_len];
1041 
1042 	for (i = 0; i < count; i++) {
1043 		pcr_select_offset = marker +
1044 			offsetof(struct tpm2_pcr_selection, size_of_select);
1045 		if (pcr_select_offset >= end) {
1046 			rc = -EFAULT;
1047 			break;
1048 		}
1049 
1050 		memcpy(&pcr_selection, marker, sizeof(pcr_selection));
1051 		chip->active_banks[i] = be16_to_cpu(pcr_selection.hash_alg);
1052 		sizeof_pcr_selection = sizeof(pcr_selection.hash_alg) +
1053 			sizeof(pcr_selection.size_of_select) +
1054 			pcr_selection.size_of_select;
1055 		marker = marker + sizeof_pcr_selection;
1056 	}
1057 
1058 out:
1059 	if (i < ARRAY_SIZE(chip->active_banks))
1060 		chip->active_banks[i] = TPM2_ALG_ERROR;
1061 
1062 	tpm_buf_destroy(&buf);
1063 
1064 	return rc;
1065 }
1066 
1067 static int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
1068 {
1069 	struct tpm_buf buf;
1070 	u32 nr_commands;
1071 	u32 *attrs;
1072 	u32 cc;
1073 	int i;
1074 	int rc;
1075 
1076 	rc = tpm2_get_tpm_pt(chip, TPM_PT_TOTAL_COMMANDS, &nr_commands, NULL);
1077 	if (rc)
1078 		goto out;
1079 
1080 	if (nr_commands > 0xFFFFF) {
1081 		rc = -EFAULT;
1082 		goto out;
1083 	}
1084 
1085 	chip->cc_attrs_tbl = devm_kzalloc(&chip->dev, 4 * nr_commands,
1086 					  GFP_KERNEL);
1087 
1088 	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
1089 	if (rc)
1090 		goto out;
1091 
1092 	tpm_buf_append_u32(&buf, TPM2_CAP_COMMANDS);
1093 	tpm_buf_append_u32(&buf, TPM2_CC_FIRST);
1094 	tpm_buf_append_u32(&buf, nr_commands);
1095 
1096 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE,
1097 			      9 + 4 * nr_commands, 0, NULL);
1098 	if (rc) {
1099 		tpm_buf_destroy(&buf);
1100 		goto out;
1101 	}
1102 
1103 	if (nr_commands !=
1104 	    be32_to_cpup((__be32 *)&buf.data[TPM_HEADER_SIZE + 5])) {
1105 		tpm_buf_destroy(&buf);
1106 		goto out;
1107 	}
1108 
1109 	chip->nr_commands = nr_commands;
1110 
1111 	attrs = (u32 *)&buf.data[TPM_HEADER_SIZE + 9];
1112 	for (i = 0; i < nr_commands; i++, attrs++) {
1113 		chip->cc_attrs_tbl[i] = be32_to_cpup(attrs);
1114 		cc = chip->cc_attrs_tbl[i] & 0xFFFF;
1115 
1116 		if (cc == TPM2_CC_CONTEXT_SAVE || cc == TPM2_CC_FLUSH_CONTEXT) {
1117 			chip->cc_attrs_tbl[i] &=
1118 				~(GENMASK(2, 0) << TPM2_CC_ATTR_CHANDLES);
1119 			chip->cc_attrs_tbl[i] |= 1 << TPM2_CC_ATTR_CHANDLES;
1120 		}
1121 	}
1122 
1123 	tpm_buf_destroy(&buf);
1124 
1125 out:
1126 	if (rc > 0)
1127 		rc = -ENODEV;
1128 	return rc;
1129 }
1130 
1131 /**
1132  * tpm2_auto_startup - Perform the standard automatic TPM initialization
1133  *                     sequence
1134  * @chip: TPM chip to use
1135  *
1136  * Returns 0 on success, < 0 in case of fatal error.
1137  */
1138 int tpm2_auto_startup(struct tpm_chip *chip)
1139 {
1140 	int rc;
1141 
1142 	rc = tpm_get_timeouts(chip);
1143 	if (rc)
1144 		goto out;
1145 
1146 	rc = tpm2_do_selftest(chip);
1147 	if (rc != 0 && rc != TPM2_RC_INITIALIZE) {
1148 		dev_err(&chip->dev, "TPM self test failed\n");
1149 		goto out;
1150 	}
1151 
1152 	if (rc == TPM2_RC_INITIALIZE) {
1153 		rc = tpm2_startup(chip, TPM2_SU_CLEAR);
1154 		if (rc)
1155 			goto out;
1156 
1157 		rc = tpm2_do_selftest(chip);
1158 		if (rc) {
1159 			dev_err(&chip->dev, "TPM self test failed\n");
1160 			goto out;
1161 		}
1162 	}
1163 
1164 	rc = tpm2_get_pcr_allocation(chip);
1165 	if (rc)
1166 		goto out;
1167 
1168 	rc = tpm2_get_cc_attrs_tbl(chip);
1169 
1170 out:
1171 	if (rc > 0)
1172 		rc = -ENODEV;
1173 	return rc;
1174 }
1175 
1176 int tpm2_find_cc(struct tpm_chip *chip, u32 cc)
1177 {
1178 	int i;
1179 
1180 	for (i = 0; i < chip->nr_commands; i++)
1181 		if (cc == (chip->cc_attrs_tbl[i] & GENMASK(15, 0)))
1182 			return i;
1183 
1184 	return -1;
1185 }
1186