xref: /openbmc/linux/drivers/char/tpm/tpm2-cmd.c (revision d3964221)
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_get_tpm_pt_in {
39 	__be32	cap_id;
40 	__be32	property_id;
41 	__be32	property_cnt;
42 } __packed;
43 
44 struct tpm2_get_tpm_pt_out {
45 	u8	more_data;
46 	__be32	subcap_id;
47 	__be32	property_cnt;
48 	__be32	property_id;
49 	__be32	value;
50 } __packed;
51 
52 struct tpm2_get_random_in {
53 	__be16	size;
54 } __packed;
55 
56 struct tpm2_get_random_out {
57 	__be16	size;
58 	u8	buffer[TPM_MAX_RNG_DATA];
59 } __packed;
60 
61 union tpm2_cmd_params {
62 	struct	tpm2_startup_in		startup_in;
63 	struct	tpm2_self_test_in	selftest_in;
64 	struct	tpm2_get_tpm_pt_in	get_tpm_pt_in;
65 	struct	tpm2_get_tpm_pt_out	get_tpm_pt_out;
66 	struct	tpm2_get_random_in	getrandom_in;
67 	struct	tpm2_get_random_out	getrandom_out;
68 };
69 
70 struct tpm2_cmd {
71 	tpm_cmd_header		header;
72 	union tpm2_cmd_params	params;
73 } __packed;
74 
75 struct tpm2_hash {
76 	unsigned int crypto_id;
77 	unsigned int tpm_id;
78 };
79 
80 static struct tpm2_hash tpm2_hash_map[] = {
81 	{HASH_ALGO_SHA1, TPM2_ALG_SHA1},
82 	{HASH_ALGO_SHA256, TPM2_ALG_SHA256},
83 	{HASH_ALGO_SHA384, TPM2_ALG_SHA384},
84 	{HASH_ALGO_SHA512, TPM2_ALG_SHA512},
85 	{HASH_ALGO_SM3_256, TPM2_ALG_SM3_256},
86 };
87 
88 /*
89  * Array with one entry per ordinal defining the maximum amount
90  * of time the chip could take to return the result. The values
91  * of the SHORT, MEDIUM, and LONG durations are taken from the
92  * PC Client Profile (PTP) specification.
93  */
94 static const u8 tpm2_ordinal_duration[TPM2_CC_LAST - TPM2_CC_FIRST + 1] = {
95 	TPM_UNDEFINED,		/* 11F */
96 	TPM_UNDEFINED,		/* 120 */
97 	TPM_LONG,		/* 121 */
98 	TPM_UNDEFINED,		/* 122 */
99 	TPM_UNDEFINED,		/* 123 */
100 	TPM_UNDEFINED,		/* 124 */
101 	TPM_UNDEFINED,		/* 125 */
102 	TPM_UNDEFINED,		/* 126 */
103 	TPM_UNDEFINED,		/* 127 */
104 	TPM_UNDEFINED,		/* 128 */
105 	TPM_LONG,		/* 129 */
106 	TPM_UNDEFINED,		/* 12a */
107 	TPM_UNDEFINED,		/* 12b */
108 	TPM_UNDEFINED,		/* 12c */
109 	TPM_UNDEFINED,		/* 12d */
110 	TPM_UNDEFINED,		/* 12e */
111 	TPM_UNDEFINED,		/* 12f */
112 	TPM_UNDEFINED,		/* 130 */
113 	TPM_UNDEFINED,		/* 131 */
114 	TPM_UNDEFINED,		/* 132 */
115 	TPM_UNDEFINED,		/* 133 */
116 	TPM_UNDEFINED,		/* 134 */
117 	TPM_UNDEFINED,		/* 135 */
118 	TPM_UNDEFINED,		/* 136 */
119 	TPM_UNDEFINED,		/* 137 */
120 	TPM_UNDEFINED,		/* 138 */
121 	TPM_UNDEFINED,		/* 139 */
122 	TPM_UNDEFINED,		/* 13a */
123 	TPM_UNDEFINED,		/* 13b */
124 	TPM_UNDEFINED,		/* 13c */
125 	TPM_UNDEFINED,		/* 13d */
126 	TPM_MEDIUM,		/* 13e */
127 	TPM_UNDEFINED,		/* 13f */
128 	TPM_UNDEFINED,		/* 140 */
129 	TPM_UNDEFINED,		/* 141 */
130 	TPM_UNDEFINED,		/* 142 */
131 	TPM_LONG,		/* 143 */
132 	TPM_MEDIUM,		/* 144 */
133 	TPM_UNDEFINED,		/* 145 */
134 	TPM_UNDEFINED,		/* 146 */
135 	TPM_UNDEFINED,		/* 147 */
136 	TPM_UNDEFINED,		/* 148 */
137 	TPM_UNDEFINED,		/* 149 */
138 	TPM_UNDEFINED,		/* 14a */
139 	TPM_UNDEFINED,		/* 14b */
140 	TPM_UNDEFINED,		/* 14c */
141 	TPM_UNDEFINED,		/* 14d */
142 	TPM_LONG,		/* 14e */
143 	TPM_UNDEFINED,		/* 14f */
144 	TPM_UNDEFINED,		/* 150 */
145 	TPM_UNDEFINED,		/* 151 */
146 	TPM_UNDEFINED,		/* 152 */
147 	TPM_UNDEFINED,		/* 153 */
148 	TPM_UNDEFINED,		/* 154 */
149 	TPM_UNDEFINED,		/* 155 */
150 	TPM_UNDEFINED,		/* 156 */
151 	TPM_UNDEFINED,		/* 157 */
152 	TPM_UNDEFINED,		/* 158 */
153 	TPM_UNDEFINED,		/* 159 */
154 	TPM_UNDEFINED,		/* 15a */
155 	TPM_UNDEFINED,		/* 15b */
156 	TPM_MEDIUM,		/* 15c */
157 	TPM_UNDEFINED,		/* 15d */
158 	TPM_UNDEFINED,		/* 15e */
159 	TPM_UNDEFINED,		/* 15f */
160 	TPM_UNDEFINED,		/* 160 */
161 	TPM_UNDEFINED,		/* 161 */
162 	TPM_UNDEFINED,		/* 162 */
163 	TPM_UNDEFINED,		/* 163 */
164 	TPM_UNDEFINED,		/* 164 */
165 	TPM_UNDEFINED,		/* 165 */
166 	TPM_UNDEFINED,		/* 166 */
167 	TPM_UNDEFINED,		/* 167 */
168 	TPM_UNDEFINED,		/* 168 */
169 	TPM_UNDEFINED,		/* 169 */
170 	TPM_UNDEFINED,		/* 16a */
171 	TPM_UNDEFINED,		/* 16b */
172 	TPM_UNDEFINED,		/* 16c */
173 	TPM_UNDEFINED,		/* 16d */
174 	TPM_UNDEFINED,		/* 16e */
175 	TPM_UNDEFINED,		/* 16f */
176 	TPM_UNDEFINED,		/* 170 */
177 	TPM_UNDEFINED,		/* 171 */
178 	TPM_UNDEFINED,		/* 172 */
179 	TPM_UNDEFINED,		/* 173 */
180 	TPM_UNDEFINED,		/* 174 */
181 	TPM_UNDEFINED,		/* 175 */
182 	TPM_UNDEFINED,		/* 176 */
183 	TPM_LONG,		/* 177 */
184 	TPM_UNDEFINED,		/* 178 */
185 	TPM_UNDEFINED,		/* 179 */
186 	TPM_MEDIUM,		/* 17a */
187 	TPM_LONG,		/* 17b */
188 	TPM_UNDEFINED,		/* 17c */
189 	TPM_UNDEFINED,		/* 17d */
190 	TPM_UNDEFINED,		/* 17e */
191 	TPM_UNDEFINED,		/* 17f */
192 	TPM_UNDEFINED,		/* 180 */
193 	TPM_UNDEFINED,		/* 181 */
194 	TPM_MEDIUM,		/* 182 */
195 	TPM_UNDEFINED,		/* 183 */
196 	TPM_UNDEFINED,		/* 184 */
197 	TPM_MEDIUM,		/* 185 */
198 	TPM_MEDIUM,		/* 186 */
199 	TPM_UNDEFINED,		/* 187 */
200 	TPM_UNDEFINED,		/* 188 */
201 	TPM_UNDEFINED,		/* 189 */
202 	TPM_UNDEFINED,		/* 18a */
203 	TPM_UNDEFINED,		/* 18b */
204 	TPM_UNDEFINED,		/* 18c */
205 	TPM_UNDEFINED,		/* 18d */
206 	TPM_UNDEFINED,		/* 18e */
207 	TPM_UNDEFINED		/* 18f */
208 };
209 
210 struct tpm2_pcr_read_out {
211 	__be32	update_cnt;
212 	__be32	pcr_selects_cnt;
213 	__be16	hash_alg;
214 	u8	pcr_select_size;
215 	u8	pcr_select[TPM2_PCR_SELECT_MIN];
216 	__be32	digests_cnt;
217 	__be16	digest_size;
218 	u8	digest[];
219 } __packed;
220 
221 /**
222  * tpm2_pcr_read() - read a PCR value
223  * @chip:	TPM chip to use.
224  * @pcr_idx:	index of the PCR to read.
225  * @res_buf:	buffer to store the resulting hash.
226  *
227  * Return: Same as with tpm_transmit_cmd.
228  */
229 int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
230 {
231 	int rc;
232 	struct tpm_buf buf;
233 	struct tpm2_pcr_read_out *out;
234 	u8 pcr_select[TPM2_PCR_SELECT_MIN] = {0};
235 
236 	if (pcr_idx >= TPM2_PLATFORM_PCR)
237 		return -EINVAL;
238 
239 	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ);
240 	if (rc)
241 		return rc;
242 
243 	pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
244 
245 	tpm_buf_append_u32(&buf, 1);
246 	tpm_buf_append_u16(&buf, TPM2_ALG_SHA1);
247 	tpm_buf_append_u8(&buf, TPM2_PCR_SELECT_MIN);
248 	tpm_buf_append(&buf, (const unsigned char *)pcr_select,
249 		       sizeof(pcr_select));
250 
251 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
252 			res_buf ? "attempting to read a pcr value" : NULL);
253 	if (rc == 0 && res_buf) {
254 		out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE];
255 		memcpy(res_buf, out->digest, SHA1_DIGEST_SIZE);
256 	}
257 
258 	tpm_buf_destroy(&buf);
259 	return rc;
260 }
261 
262 struct tpm2_null_auth_area {
263 	__be32  handle;
264 	__be16  nonce_size;
265 	u8  attributes;
266 	__be16  auth_size;
267 } __packed;
268 
269 /**
270  * tpm2_pcr_extend() - extend a PCR value
271  *
272  * @chip:	TPM chip to use.
273  * @pcr_idx:	index of the PCR.
274  * @count:	number of digests passed.
275  * @digests:	list of pcr banks and corresponding digest values to extend.
276  *
277  * Return: Same as with tpm_transmit_cmd.
278  */
279 int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, u32 count,
280 		    struct tpm2_digest *digests)
281 {
282 	struct tpm_buf buf;
283 	struct tpm2_null_auth_area auth_area;
284 	int rc;
285 	int i;
286 	int j;
287 
288 	if (count > ARRAY_SIZE(chip->active_banks))
289 		return -EINVAL;
290 
291 	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
292 	if (rc)
293 		return rc;
294 
295 	tpm_buf_append_u32(&buf, pcr_idx);
296 
297 	auth_area.handle = cpu_to_be32(TPM2_RS_PW);
298 	auth_area.nonce_size = 0;
299 	auth_area.attributes = 0;
300 	auth_area.auth_size = 0;
301 
302 	tpm_buf_append_u32(&buf, sizeof(struct tpm2_null_auth_area));
303 	tpm_buf_append(&buf, (const unsigned char *)&auth_area,
304 		       sizeof(auth_area));
305 	tpm_buf_append_u32(&buf, count);
306 
307 	for (i = 0; i < count; i++) {
308 		for (j = 0; j < ARRAY_SIZE(tpm2_hash_map); j++) {
309 			if (digests[i].alg_id != tpm2_hash_map[j].tpm_id)
310 				continue;
311 			tpm_buf_append_u16(&buf, digests[i].alg_id);
312 			tpm_buf_append(&buf, (const unsigned char
313 					      *)&digests[i].digest,
314 			       hash_digest_size[tpm2_hash_map[j].crypto_id]);
315 		}
316 	}
317 
318 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
319 			      "attempting extend a PCR value");
320 
321 	tpm_buf_destroy(&buf);
322 
323 	return rc;
324 }
325 
326 
327 #define TPM2_GETRANDOM_IN_SIZE \
328 	(sizeof(struct tpm_input_header) + \
329 	 sizeof(struct tpm2_get_random_in))
330 
331 static const struct tpm_input_header tpm2_getrandom_header = {
332 	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
333 	.length = cpu_to_be32(TPM2_GETRANDOM_IN_SIZE),
334 	.ordinal = cpu_to_be32(TPM2_CC_GET_RANDOM)
335 };
336 
337 /**
338  * tpm2_get_random() - get random bytes from the TPM RNG
339  *
340  * @chip: TPM chip to use
341  * @out: destination buffer for the random bytes
342  * @max: the max number of bytes to write to @out
343  *
344  * Return:
345  *    Size of the output buffer, or -EIO on error.
346  */
347 int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
348 {
349 	struct tpm2_cmd cmd;
350 	u32 recd, rlength;
351 	u32 num_bytes;
352 	int err;
353 	int total = 0;
354 	int retries = 5;
355 	u8 *dest = out;
356 
357 	num_bytes = min_t(u32, max, sizeof(cmd.params.getrandom_out.buffer));
358 
359 	if (!out || !num_bytes ||
360 	    max > sizeof(cmd.params.getrandom_out.buffer))
361 		return -EINVAL;
362 
363 	do {
364 		cmd.header.in = tpm2_getrandom_header;
365 		cmd.params.getrandom_in.size = cpu_to_be16(num_bytes);
366 
367 		err = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd),
368 				       offsetof(struct tpm2_get_random_out,
369 						buffer),
370 				       0, "attempting get random");
371 		if (err)
372 			break;
373 
374 		recd = min_t(u32, be16_to_cpu(cmd.params.getrandom_out.size),
375 			     num_bytes);
376 		rlength = be32_to_cpu(cmd.header.out.length);
377 		if (rlength < offsetof(struct tpm2_get_random_out, buffer) +
378 			      recd)
379 			return -EFAULT;
380 		memcpy(dest, cmd.params.getrandom_out.buffer, recd);
381 
382 		dest += recd;
383 		total += recd;
384 		num_bytes -= recd;
385 	} while (retries-- && total < max);
386 
387 	return total ? total : -EIO;
388 }
389 
390 #define TPM2_GET_TPM_PT_IN_SIZE \
391 	(sizeof(struct tpm_input_header) + \
392 	 sizeof(struct tpm2_get_tpm_pt_in))
393 
394 #define TPM2_GET_TPM_PT_OUT_BODY_SIZE \
395 	 sizeof(struct tpm2_get_tpm_pt_out)
396 
397 static const struct tpm_input_header tpm2_get_tpm_pt_header = {
398 	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
399 	.length = cpu_to_be32(TPM2_GET_TPM_PT_IN_SIZE),
400 	.ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
401 };
402 
403 /**
404  * tpm2_flush_context_cmd() - execute a TPM2_FlushContext command
405  * @chip: TPM chip to use
406  * @payload: the key data in clear and encrypted form
407  * @options: authentication values and other options
408  *
409  * Return: same as with tpm_transmit_cmd
410  */
411 void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
412 			    unsigned int flags)
413 {
414 	struct tpm_buf buf;
415 	int rc;
416 
417 	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
418 	if (rc) {
419 		dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n",
420 			 handle);
421 		return;
422 	}
423 
424 	tpm_buf_append_u32(&buf, handle);
425 
426 	(void) tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, flags,
427 				"flushing context");
428 
429 	tpm_buf_destroy(&buf);
430 }
431 
432 /**
433  * tpm_buf_append_auth() - append TPMS_AUTH_COMMAND to the buffer.
434  *
435  * @buf: an allocated tpm_buf instance
436  * @session_handle: session handle
437  * @nonce: the session nonce, may be NULL if not used
438  * @nonce_len: the session nonce length, may be 0 if not used
439  * @attributes: the session attributes
440  * @hmac: the session HMAC or password, may be NULL if not used
441  * @hmac_len: the session HMAC or password length, maybe 0 if not used
442  */
443 static void tpm2_buf_append_auth(struct tpm_buf *buf, u32 session_handle,
444 				 const u8 *nonce, u16 nonce_len,
445 				 u8 attributes,
446 				 const u8 *hmac, u16 hmac_len)
447 {
448 	tpm_buf_append_u32(buf, 9 + nonce_len + hmac_len);
449 	tpm_buf_append_u32(buf, session_handle);
450 	tpm_buf_append_u16(buf, nonce_len);
451 
452 	if (nonce && nonce_len)
453 		tpm_buf_append(buf, nonce, nonce_len);
454 
455 	tpm_buf_append_u8(buf, attributes);
456 	tpm_buf_append_u16(buf, hmac_len);
457 
458 	if (hmac && hmac_len)
459 		tpm_buf_append(buf, hmac, hmac_len);
460 }
461 
462 /**
463  * tpm2_seal_trusted() - seal the payload of a trusted key
464  *
465  * @chip: TPM chip to use
466  * @payload: the key data in clear and encrypted form
467  * @options: authentication values and other options
468  *
469  * Return: < 0 on error and 0 on success.
470  */
471 int tpm2_seal_trusted(struct tpm_chip *chip,
472 		      struct trusted_key_payload *payload,
473 		      struct trusted_key_options *options)
474 {
475 	unsigned int blob_len;
476 	struct tpm_buf buf;
477 	u32 hash, rlength;
478 	int i;
479 	int rc;
480 
481 	for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {
482 		if (options->hash == tpm2_hash_map[i].crypto_id) {
483 			hash = tpm2_hash_map[i].tpm_id;
484 			break;
485 		}
486 	}
487 
488 	if (i == ARRAY_SIZE(tpm2_hash_map))
489 		return -EINVAL;
490 
491 	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
492 	if (rc)
493 		return rc;
494 
495 	tpm_buf_append_u32(&buf, options->keyhandle);
496 	tpm2_buf_append_auth(&buf, TPM2_RS_PW,
497 			     NULL /* nonce */, 0,
498 			     0 /* session_attributes */,
499 			     options->keyauth /* hmac */,
500 			     TPM_DIGEST_SIZE);
501 
502 	/* sensitive */
503 	tpm_buf_append_u16(&buf, 4 + TPM_DIGEST_SIZE + payload->key_len + 1);
504 
505 	tpm_buf_append_u16(&buf, TPM_DIGEST_SIZE);
506 	tpm_buf_append(&buf, options->blobauth, TPM_DIGEST_SIZE);
507 	tpm_buf_append_u16(&buf, payload->key_len + 1);
508 	tpm_buf_append(&buf, payload->key, payload->key_len);
509 	tpm_buf_append_u8(&buf, payload->migratable);
510 
511 	/* public */
512 	tpm_buf_append_u16(&buf, 14 + options->policydigest_len);
513 	tpm_buf_append_u16(&buf, TPM2_ALG_KEYEDHASH);
514 	tpm_buf_append_u16(&buf, hash);
515 
516 	/* policy */
517 	if (options->policydigest_len) {
518 		tpm_buf_append_u32(&buf, 0);
519 		tpm_buf_append_u16(&buf, options->policydigest_len);
520 		tpm_buf_append(&buf, options->policydigest,
521 			       options->policydigest_len);
522 	} else {
523 		tpm_buf_append_u32(&buf, TPM2_OA_USER_WITH_AUTH);
524 		tpm_buf_append_u16(&buf, 0);
525 	}
526 
527 	/* public parameters */
528 	tpm_buf_append_u16(&buf, TPM2_ALG_NULL);
529 	tpm_buf_append_u16(&buf, 0);
530 
531 	/* outside info */
532 	tpm_buf_append_u16(&buf, 0);
533 
534 	/* creation PCR */
535 	tpm_buf_append_u32(&buf, 0);
536 
537 	if (buf.flags & TPM_BUF_OVERFLOW) {
538 		rc = -E2BIG;
539 		goto out;
540 	}
541 
542 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 4, 0,
543 			      "sealing data");
544 	if (rc)
545 		goto out;
546 
547 	blob_len = be32_to_cpup((__be32 *) &buf.data[TPM_HEADER_SIZE]);
548 	if (blob_len > MAX_BLOB_SIZE) {
549 		rc = -E2BIG;
550 		goto out;
551 	}
552 	rlength = be32_to_cpu(((struct tpm2_cmd *)&buf)->header.out.length);
553 	if (rlength < TPM_HEADER_SIZE + 4 + blob_len) {
554 		rc = -EFAULT;
555 		goto out;
556 	}
557 
558 	memcpy(payload->blob, &buf.data[TPM_HEADER_SIZE + 4], blob_len);
559 	payload->blob_len = blob_len;
560 
561 out:
562 	tpm_buf_destroy(&buf);
563 
564 	if (rc > 0) {
565 		if (tpm2_rc_value(rc) == TPM2_RC_HASH)
566 			rc = -EINVAL;
567 		else
568 			rc = -EPERM;
569 	}
570 
571 	return rc;
572 }
573 
574 /**
575  * tpm2_load_cmd() - execute a TPM2_Load command
576  *
577  * @chip: TPM chip to use
578  * @payload: the key data in clear and encrypted form
579  * @options: authentication values and other options
580  * @blob_handle: returned blob handle
581  * @flags: tpm transmit flags
582  *
583  * Return: 0 on success.
584  *        -E2BIG on wrong payload size.
585  *        -EPERM on tpm error status.
586  *        < 0 error from tpm_transmit_cmd.
587  */
588 static int tpm2_load_cmd(struct tpm_chip *chip,
589 			 struct trusted_key_payload *payload,
590 			 struct trusted_key_options *options,
591 			 u32 *blob_handle, unsigned int flags)
592 {
593 	struct tpm_buf buf;
594 	unsigned int private_len;
595 	unsigned int public_len;
596 	unsigned int blob_len;
597 	int rc;
598 
599 	private_len = be16_to_cpup((__be16 *) &payload->blob[0]);
600 	if (private_len > (payload->blob_len - 2))
601 		return -E2BIG;
602 
603 	public_len = be16_to_cpup((__be16 *) &payload->blob[2 + private_len]);
604 	blob_len = private_len + public_len + 4;
605 	if (blob_len > payload->blob_len)
606 		return -E2BIG;
607 
608 	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
609 	if (rc)
610 		return rc;
611 
612 	tpm_buf_append_u32(&buf, options->keyhandle);
613 	tpm2_buf_append_auth(&buf, TPM2_RS_PW,
614 			     NULL /* nonce */, 0,
615 			     0 /* session_attributes */,
616 			     options->keyauth /* hmac */,
617 			     TPM_DIGEST_SIZE);
618 
619 	tpm_buf_append(&buf, payload->blob, blob_len);
620 
621 	if (buf.flags & TPM_BUF_OVERFLOW) {
622 		rc = -E2BIG;
623 		goto out;
624 	}
625 
626 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 4, flags,
627 			      "loading blob");
628 	if (!rc)
629 		*blob_handle = be32_to_cpup(
630 			(__be32 *) &buf.data[TPM_HEADER_SIZE]);
631 
632 out:
633 	tpm_buf_destroy(&buf);
634 
635 	if (rc > 0)
636 		rc = -EPERM;
637 
638 	return rc;
639 }
640 
641 /**
642  * tpm2_unseal_cmd() - execute a TPM2_Unload command
643  *
644  * @chip: TPM chip to use
645  * @payload: the key data in clear and encrypted form
646  * @options: authentication values and other options
647  * @blob_handle: blob handle
648  * @flags: tpm_transmit_cmd flags
649  *
650  * Return: 0 on success
651  *         -EPERM on tpm error status
652  *         < 0 error from tpm_transmit_cmd
653  */
654 static int tpm2_unseal_cmd(struct tpm_chip *chip,
655 			   struct trusted_key_payload *payload,
656 			   struct trusted_key_options *options,
657 			   u32 blob_handle, unsigned int flags)
658 {
659 	struct tpm_buf buf;
660 	u16 data_len;
661 	u8 *data;
662 	int rc;
663 	u32 rlength;
664 
665 	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
666 	if (rc)
667 		return rc;
668 
669 	tpm_buf_append_u32(&buf, blob_handle);
670 	tpm2_buf_append_auth(&buf,
671 			     options->policyhandle ?
672 			     options->policyhandle : TPM2_RS_PW,
673 			     NULL /* nonce */, 0,
674 			     TPM2_SA_CONTINUE_SESSION,
675 			     options->blobauth /* hmac */,
676 			     TPM_DIGEST_SIZE);
677 
678 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 6, flags,
679 			      "unsealing");
680 	if (rc > 0)
681 		rc = -EPERM;
682 
683 	if (!rc) {
684 		data_len = be16_to_cpup(
685 			(__be16 *) &buf.data[TPM_HEADER_SIZE + 4]);
686 
687 		rlength = be32_to_cpu(((struct tpm2_cmd *)&buf)
688 					->header.out.length);
689 		if (rlength < TPM_HEADER_SIZE + 6 + data_len) {
690 			rc = -EFAULT;
691 			goto out;
692 		}
693 		data = &buf.data[TPM_HEADER_SIZE + 6];
694 
695 		memcpy(payload->key, data, data_len - 1);
696 		payload->key_len = data_len - 1;
697 		payload->migratable = data[data_len - 1];
698 	}
699 
700 out:
701 	tpm_buf_destroy(&buf);
702 	return rc;
703 }
704 
705 /**
706  * tpm2_unseal_trusted() - unseal the payload of a trusted key
707  *
708  * @chip: TPM chip to use
709  * @payload: the key data in clear and encrypted form
710  * @options: authentication values and other options
711  *
712  * Return: Same as with tpm_transmit_cmd.
713  */
714 int tpm2_unseal_trusted(struct tpm_chip *chip,
715 			struct trusted_key_payload *payload,
716 			struct trusted_key_options *options)
717 {
718 	u32 blob_handle;
719 	int rc;
720 
721 	mutex_lock(&chip->tpm_mutex);
722 	rc = tpm2_load_cmd(chip, payload, options, &blob_handle,
723 			   TPM_TRANSMIT_UNLOCKED);
724 	if (rc)
725 		goto out;
726 
727 	rc = tpm2_unseal_cmd(chip, payload, options, blob_handle,
728 			     TPM_TRANSMIT_UNLOCKED);
729 	tpm2_flush_context_cmd(chip, blob_handle, TPM_TRANSMIT_UNLOCKED);
730 out:
731 	mutex_unlock(&chip->tpm_mutex);
732 	return rc;
733 }
734 
735 /**
736  * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
737  * @chip:		TPM chip to use.
738  * @property_id:	property ID.
739  * @value:		output variable.
740  * @desc:		passed to tpm_transmit_cmd()
741  *
742  * Return: Same as with tpm_transmit_cmd.
743  */
744 ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
745 			const char *desc)
746 {
747 	struct tpm2_cmd cmd;
748 	int rc;
749 
750 	cmd.header.in = tpm2_get_tpm_pt_header;
751 	cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
752 	cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(property_id);
753 	cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
754 
755 	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd),
756 			      TPM2_GET_TPM_PT_OUT_BODY_SIZE, 0, desc);
757 	if (!rc)
758 		*value = be32_to_cpu(cmd.params.get_tpm_pt_out.value);
759 
760 	return rc;
761 }
762 EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
763 
764 #define TPM2_SHUTDOWN_IN_SIZE \
765 	(sizeof(struct tpm_input_header) + \
766 	 sizeof(struct tpm2_startup_in))
767 
768 static const struct tpm_input_header tpm2_shutdown_header = {
769 	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
770 	.length = cpu_to_be32(TPM2_SHUTDOWN_IN_SIZE),
771 	.ordinal = cpu_to_be32(TPM2_CC_SHUTDOWN)
772 };
773 
774 /**
775  * tpm2_shutdown() - send shutdown command to the TPM chip
776  *
777  * @chip:		TPM chip to use.
778  * @shutdown_type:	shutdown type. The value is either
779  *			TPM_SU_CLEAR or TPM_SU_STATE.
780  */
781 void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
782 {
783 	struct tpm2_cmd cmd;
784 	int rc;
785 
786 	cmd.header.in = tpm2_shutdown_header;
787 	cmd.params.startup_in.startup_type = cpu_to_be16(shutdown_type);
788 
789 	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0,
790 			      "stopping the TPM");
791 
792 	/* In places where shutdown command is sent there's no much we can do
793 	 * except print the error code on a system failure.
794 	 */
795 	if (rc < 0 && rc != -EPIPE)
796 		dev_warn(&chip->dev, "transmit returned %d while stopping the TPM",
797 			 rc);
798 }
799 
800 /*
801  * tpm2_calc_ordinal_duration() - maximum duration for a command
802  *
803  * @chip:	TPM chip to use.
804  * @ordinal:	command code number.
805  *
806  * Return: maximum duration for a command
807  */
808 unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
809 {
810 	int index = TPM_UNDEFINED;
811 	int duration = 0;
812 
813 	if (ordinal >= TPM2_CC_FIRST && ordinal <= TPM2_CC_LAST)
814 		index = tpm2_ordinal_duration[ordinal - TPM2_CC_FIRST];
815 
816 	if (index != TPM_UNDEFINED)
817 		duration = chip->duration[index];
818 
819 	if (duration <= 0)
820 		duration = 2 * 60 * HZ;
821 
822 	return duration;
823 }
824 EXPORT_SYMBOL_GPL(tpm2_calc_ordinal_duration);
825 
826 #define TPM2_SELF_TEST_IN_SIZE \
827 	(sizeof(struct tpm_input_header) + \
828 	 sizeof(struct tpm2_self_test_in))
829 
830 static const struct tpm_input_header tpm2_selftest_header = {
831 	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
832 	.length = cpu_to_be32(TPM2_SELF_TEST_IN_SIZE),
833 	.ordinal = cpu_to_be32(TPM2_CC_SELF_TEST)
834 };
835 
836 /**
837  * tpm2_do_selftest() - ensure that all self tests have passed
838  *
839  * @chip: TPM chip to use
840  *
841  * Return: Same as with tpm_transmit_cmd.
842  *
843  * The TPM can either run all self tests synchronously and then return
844  * RC_SUCCESS once all tests were successful. Or it can choose to run the tests
845  * asynchronously and return RC_TESTING immediately while the self tests still
846  * execute in the background. This function handles both cases and waits until
847  * all tests have completed.
848  */
849 static int tpm2_do_selftest(struct tpm_chip *chip)
850 {
851 	int rc;
852 	unsigned int delay_msec = 20;
853 	long duration;
854 	struct tpm2_cmd cmd;
855 
856 	duration = jiffies_to_msecs(
857 		tpm2_calc_ordinal_duration(chip, TPM2_CC_SELF_TEST));
858 
859 	while (duration > 0) {
860 		cmd.header.in = tpm2_selftest_header;
861 		cmd.params.selftest_in.full_test = 0;
862 
863 		rc = tpm_transmit_cmd(chip, NULL, &cmd, TPM2_SELF_TEST_IN_SIZE,
864 				      0, 0, "continue selftest");
865 
866 		if (rc != TPM2_RC_TESTING)
867 			break;
868 
869 		tpm_msleep(delay_msec);
870 		duration -= delay_msec;
871 
872 		/* wait longer the next round */
873 		delay_msec *= 2;
874 	}
875 
876 	return rc;
877 }
878 
879 /**
880  * tpm2_probe() - probe TPM 2.0
881  * @chip: TPM chip to use
882  *
883  * Return: < 0 error and 0 on success.
884  *
885  * Send idempotent TPM 2.0 command and see whether TPM 2.0 chip replied based on
886  * the reply tag.
887  */
888 int tpm2_probe(struct tpm_chip *chip)
889 {
890 	struct tpm2_cmd cmd;
891 	int rc;
892 
893 	cmd.header.in = tpm2_get_tpm_pt_header;
894 	cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
895 	cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(0x100);
896 	cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
897 
898 	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0, NULL);
899 	if (rc <  0)
900 		return rc;
901 
902 	if (be16_to_cpu(cmd.header.out.tag) == TPM2_ST_NO_SESSIONS)
903 		chip->flags |= TPM_CHIP_FLAG_TPM2;
904 
905 	return 0;
906 }
907 EXPORT_SYMBOL_GPL(tpm2_probe);
908 
909 struct tpm2_pcr_selection {
910 	__be16  hash_alg;
911 	u8  size_of_select;
912 	u8  pcr_select[3];
913 } __packed;
914 
915 static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
916 {
917 	struct tpm2_pcr_selection pcr_selection;
918 	struct tpm_buf buf;
919 	void *marker;
920 	void *end;
921 	void *pcr_select_offset;
922 	unsigned int count;
923 	u32 sizeof_pcr_selection;
924 	u32 rsp_len;
925 	int rc;
926 	int i = 0;
927 
928 	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
929 	if (rc)
930 		return rc;
931 
932 	tpm_buf_append_u32(&buf, TPM2_CAP_PCRS);
933 	tpm_buf_append_u32(&buf, 0);
934 	tpm_buf_append_u32(&buf, 1);
935 
936 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 9, 0,
937 			      "get tpm pcr allocation");
938 	if (rc)
939 		goto out;
940 
941 	count = be32_to_cpup(
942 		(__be32 *)&buf.data[TPM_HEADER_SIZE + 5]);
943 
944 	if (count > ARRAY_SIZE(chip->active_banks)) {
945 		rc = -ENODEV;
946 		goto out;
947 	}
948 
949 	marker = &buf.data[TPM_HEADER_SIZE + 9];
950 
951 	rsp_len = be32_to_cpup((__be32 *)&buf.data[2]);
952 	end = &buf.data[rsp_len];
953 
954 	for (i = 0; i < count; i++) {
955 		pcr_select_offset = marker +
956 			offsetof(struct tpm2_pcr_selection, size_of_select);
957 		if (pcr_select_offset >= end) {
958 			rc = -EFAULT;
959 			break;
960 		}
961 
962 		memcpy(&pcr_selection, marker, sizeof(pcr_selection));
963 		chip->active_banks[i] = be16_to_cpu(pcr_selection.hash_alg);
964 		sizeof_pcr_selection = sizeof(pcr_selection.hash_alg) +
965 			sizeof(pcr_selection.size_of_select) +
966 			pcr_selection.size_of_select;
967 		marker = marker + sizeof_pcr_selection;
968 	}
969 
970 out:
971 	if (i < ARRAY_SIZE(chip->active_banks))
972 		chip->active_banks[i] = TPM2_ALG_ERROR;
973 
974 	tpm_buf_destroy(&buf);
975 
976 	return rc;
977 }
978 
979 static int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
980 {
981 	struct tpm_buf buf;
982 	u32 nr_commands;
983 	__be32 *attrs;
984 	u32 cc;
985 	int i;
986 	int rc;
987 
988 	rc = tpm2_get_tpm_pt(chip, TPM_PT_TOTAL_COMMANDS, &nr_commands, NULL);
989 	if (rc)
990 		goto out;
991 
992 	if (nr_commands > 0xFFFFF) {
993 		rc = -EFAULT;
994 		goto out;
995 	}
996 
997 	chip->cc_attrs_tbl = devm_kzalloc(&chip->dev, 4 * nr_commands,
998 					  GFP_KERNEL);
999 
1000 	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
1001 	if (rc)
1002 		goto out;
1003 
1004 	tpm_buf_append_u32(&buf, TPM2_CAP_COMMANDS);
1005 	tpm_buf_append_u32(&buf, TPM2_CC_FIRST);
1006 	tpm_buf_append_u32(&buf, nr_commands);
1007 
1008 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE,
1009 			      9 + 4 * nr_commands, 0, NULL);
1010 	if (rc) {
1011 		tpm_buf_destroy(&buf);
1012 		goto out;
1013 	}
1014 
1015 	if (nr_commands !=
1016 	    be32_to_cpup((__be32 *)&buf.data[TPM_HEADER_SIZE + 5])) {
1017 		tpm_buf_destroy(&buf);
1018 		goto out;
1019 	}
1020 
1021 	chip->nr_commands = nr_commands;
1022 
1023 	attrs = (__be32 *)&buf.data[TPM_HEADER_SIZE + 9];
1024 	for (i = 0; i < nr_commands; i++, attrs++) {
1025 		chip->cc_attrs_tbl[i] = be32_to_cpup(attrs);
1026 		cc = chip->cc_attrs_tbl[i] & 0xFFFF;
1027 
1028 		if (cc == TPM2_CC_CONTEXT_SAVE || cc == TPM2_CC_FLUSH_CONTEXT) {
1029 			chip->cc_attrs_tbl[i] &=
1030 				~(GENMASK(2, 0) << TPM2_CC_ATTR_CHANDLES);
1031 			chip->cc_attrs_tbl[i] |= 1 << TPM2_CC_ATTR_CHANDLES;
1032 		}
1033 	}
1034 
1035 	tpm_buf_destroy(&buf);
1036 
1037 out:
1038 	if (rc > 0)
1039 		rc = -ENODEV;
1040 	return rc;
1041 }
1042 
1043 /**
1044  * tpm2_auto_startup - Perform the standard automatic TPM initialization
1045  *                     sequence
1046  * @chip: TPM chip to use
1047  *
1048  * Returns 0 on success, < 0 in case of fatal error.
1049  */
1050 int tpm2_auto_startup(struct tpm_chip *chip)
1051 {
1052 	int rc;
1053 
1054 	rc = tpm_get_timeouts(chip);
1055 	if (rc)
1056 		goto out;
1057 
1058 	rc = tpm2_do_selftest(chip);
1059 	if (rc != 0 && rc != TPM2_RC_INITIALIZE) {
1060 		dev_err(&chip->dev, "TPM self test failed\n");
1061 		goto out;
1062 	}
1063 
1064 	if (rc == TPM2_RC_INITIALIZE) {
1065 		rc = tpm_startup(chip);
1066 		if (rc)
1067 			goto out;
1068 
1069 		rc = tpm2_do_selftest(chip);
1070 		if (rc) {
1071 			dev_err(&chip->dev, "TPM self test failed\n");
1072 			goto out;
1073 		}
1074 	}
1075 
1076 	rc = tpm2_get_pcr_allocation(chip);
1077 	if (rc)
1078 		goto out;
1079 
1080 	rc = tpm2_get_cc_attrs_tbl(chip);
1081 
1082 out:
1083 	if (rc > 0)
1084 		rc = -ENODEV;
1085 	return rc;
1086 }
1087 
1088 int tpm2_find_cc(struct tpm_chip *chip, u32 cc)
1089 {
1090 	int i;
1091 
1092 	for (i = 0; i < chip->nr_commands; i++)
1093 		if (cc == (chip->cc_attrs_tbl[i] & GENMASK(15, 0)))
1094 			return i;
1095 
1096 	return -1;
1097 }
1098