xref: /openbmc/linux/drivers/char/tpm/tpm2-cmd.c (revision 2359ccdd)
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_get_tpm_pt_in {
35 	__be32	cap_id;
36 	__be32	property_id;
37 	__be32	property_cnt;
38 } __packed;
39 
40 struct tpm2_get_tpm_pt_out {
41 	u8	more_data;
42 	__be32	subcap_id;
43 	__be32	property_cnt;
44 	__be32	property_id;
45 	__be32	value;
46 } __packed;
47 
48 struct tpm2_get_random_in {
49 	__be16	size;
50 } __packed;
51 
52 struct tpm2_get_random_out {
53 	__be16	size;
54 	u8	buffer[TPM_MAX_RNG_DATA];
55 } __packed;
56 
57 union tpm2_cmd_params {
58 	struct	tpm2_startup_in		startup_in;
59 	struct	tpm2_get_tpm_pt_in	get_tpm_pt_in;
60 	struct	tpm2_get_tpm_pt_out	get_tpm_pt_out;
61 	struct	tpm2_get_random_in	getrandom_in;
62 	struct	tpm2_get_random_out	getrandom_out;
63 };
64 
65 struct tpm2_cmd {
66 	tpm_cmd_header		header;
67 	union tpm2_cmd_params	params;
68 } __packed;
69 
70 struct tpm2_hash {
71 	unsigned int crypto_id;
72 	unsigned int tpm_id;
73 };
74 
75 static struct tpm2_hash tpm2_hash_map[] = {
76 	{HASH_ALGO_SHA1, TPM2_ALG_SHA1},
77 	{HASH_ALGO_SHA256, TPM2_ALG_SHA256},
78 	{HASH_ALGO_SHA384, TPM2_ALG_SHA384},
79 	{HASH_ALGO_SHA512, TPM2_ALG_SHA512},
80 	{HASH_ALGO_SM3_256, TPM2_ALG_SM3_256},
81 };
82 
83 /*
84  * Array with one entry per ordinal defining the maximum amount
85  * of time the chip could take to return the result. The values
86  * of the SHORT, MEDIUM, and LONG durations are taken from the
87  * PC Client Profile (PTP) specification.
88  * LONG_LONG is for commands that generates keys which empirically
89  * takes longer time on some systems.
90  */
91 static const u8 tpm2_ordinal_duration[TPM2_CC_LAST - TPM2_CC_FIRST + 1] = {
92 	TPM_UNDEFINED,		/* 11F */
93 	TPM_UNDEFINED,		/* 120 */
94 	TPM_LONG,		/* 121 */
95 	TPM_UNDEFINED,		/* 122 */
96 	TPM_UNDEFINED,		/* 123 */
97 	TPM_UNDEFINED,		/* 124 */
98 	TPM_UNDEFINED,		/* 125 */
99 	TPM_UNDEFINED,		/* 126 */
100 	TPM_UNDEFINED,		/* 127 */
101 	TPM_UNDEFINED,		/* 128 */
102 	TPM_LONG,		/* 129 */
103 	TPM_UNDEFINED,		/* 12a */
104 	TPM_UNDEFINED,		/* 12b */
105 	TPM_UNDEFINED,		/* 12c */
106 	TPM_UNDEFINED,		/* 12d */
107 	TPM_UNDEFINED,		/* 12e */
108 	TPM_UNDEFINED,		/* 12f */
109 	TPM_UNDEFINED,		/* 130 */
110 	TPM_LONG_LONG,		/* 131 */
111 	TPM_UNDEFINED,		/* 132 */
112 	TPM_UNDEFINED,		/* 133 */
113 	TPM_UNDEFINED,		/* 134 */
114 	TPM_UNDEFINED,		/* 135 */
115 	TPM_UNDEFINED,		/* 136 */
116 	TPM_UNDEFINED,		/* 137 */
117 	TPM_UNDEFINED,		/* 138 */
118 	TPM_UNDEFINED,		/* 139 */
119 	TPM_UNDEFINED,		/* 13a */
120 	TPM_UNDEFINED,		/* 13b */
121 	TPM_UNDEFINED,		/* 13c */
122 	TPM_UNDEFINED,		/* 13d */
123 	TPM_MEDIUM,		/* 13e */
124 	TPM_UNDEFINED,		/* 13f */
125 	TPM_UNDEFINED,		/* 140 */
126 	TPM_UNDEFINED,		/* 141 */
127 	TPM_UNDEFINED,		/* 142 */
128 	TPM_LONG,		/* 143 */
129 	TPM_MEDIUM,		/* 144 */
130 	TPM_UNDEFINED,		/* 145 */
131 	TPM_UNDEFINED,		/* 146 */
132 	TPM_UNDEFINED,		/* 147 */
133 	TPM_UNDEFINED,		/* 148 */
134 	TPM_UNDEFINED,		/* 149 */
135 	TPM_UNDEFINED,		/* 14a */
136 	TPM_UNDEFINED,		/* 14b */
137 	TPM_UNDEFINED,		/* 14c */
138 	TPM_UNDEFINED,		/* 14d */
139 	TPM_LONG,		/* 14e */
140 	TPM_UNDEFINED,		/* 14f */
141 	TPM_UNDEFINED,		/* 150 */
142 	TPM_UNDEFINED,		/* 151 */
143 	TPM_UNDEFINED,		/* 152 */
144 	TPM_LONG_LONG,		/* 153 */
145 	TPM_UNDEFINED,		/* 154 */
146 	TPM_UNDEFINED,		/* 155 */
147 	TPM_UNDEFINED,		/* 156 */
148 	TPM_UNDEFINED,		/* 157 */
149 	TPM_UNDEFINED,		/* 158 */
150 	TPM_UNDEFINED,		/* 159 */
151 	TPM_UNDEFINED,		/* 15a */
152 	TPM_UNDEFINED,		/* 15b */
153 	TPM_MEDIUM,		/* 15c */
154 	TPM_UNDEFINED,		/* 15d */
155 	TPM_UNDEFINED,		/* 15e */
156 	TPM_UNDEFINED,		/* 15f */
157 	TPM_UNDEFINED,		/* 160 */
158 	TPM_UNDEFINED,		/* 161 */
159 	TPM_UNDEFINED,		/* 162 */
160 	TPM_UNDEFINED,		/* 163 */
161 	TPM_UNDEFINED,		/* 164 */
162 	TPM_UNDEFINED,		/* 165 */
163 	TPM_UNDEFINED,		/* 166 */
164 	TPM_UNDEFINED,		/* 167 */
165 	TPM_UNDEFINED,		/* 168 */
166 	TPM_UNDEFINED,		/* 169 */
167 	TPM_UNDEFINED,		/* 16a */
168 	TPM_UNDEFINED,		/* 16b */
169 	TPM_UNDEFINED,		/* 16c */
170 	TPM_UNDEFINED,		/* 16d */
171 	TPM_UNDEFINED,		/* 16e */
172 	TPM_UNDEFINED,		/* 16f */
173 	TPM_UNDEFINED,		/* 170 */
174 	TPM_UNDEFINED,		/* 171 */
175 	TPM_UNDEFINED,		/* 172 */
176 	TPM_UNDEFINED,		/* 173 */
177 	TPM_UNDEFINED,		/* 174 */
178 	TPM_UNDEFINED,		/* 175 */
179 	TPM_UNDEFINED,		/* 176 */
180 	TPM_LONG,		/* 177 */
181 	TPM_UNDEFINED,		/* 178 */
182 	TPM_UNDEFINED,		/* 179 */
183 	TPM_MEDIUM,		/* 17a */
184 	TPM_LONG,		/* 17b */
185 	TPM_UNDEFINED,		/* 17c */
186 	TPM_UNDEFINED,		/* 17d */
187 	TPM_UNDEFINED,		/* 17e */
188 	TPM_UNDEFINED,		/* 17f */
189 	TPM_UNDEFINED,		/* 180 */
190 	TPM_UNDEFINED,		/* 181 */
191 	TPM_MEDIUM,		/* 182 */
192 	TPM_UNDEFINED,		/* 183 */
193 	TPM_UNDEFINED,		/* 184 */
194 	TPM_MEDIUM,		/* 185 */
195 	TPM_MEDIUM,		/* 186 */
196 	TPM_UNDEFINED,		/* 187 */
197 	TPM_UNDEFINED,		/* 188 */
198 	TPM_UNDEFINED,		/* 189 */
199 	TPM_UNDEFINED,		/* 18a */
200 	TPM_UNDEFINED,		/* 18b */
201 	TPM_UNDEFINED,		/* 18c */
202 	TPM_UNDEFINED,		/* 18d */
203 	TPM_UNDEFINED,		/* 18e */
204 	TPM_UNDEFINED		/* 18f */
205 };
206 
207 struct tpm2_pcr_read_out {
208 	__be32	update_cnt;
209 	__be32	pcr_selects_cnt;
210 	__be16	hash_alg;
211 	u8	pcr_select_size;
212 	u8	pcr_select[TPM2_PCR_SELECT_MIN];
213 	__be32	digests_cnt;
214 	__be16	digest_size;
215 	u8	digest[];
216 } __packed;
217 
218 /**
219  * tpm2_pcr_read() - read a PCR value
220  * @chip:	TPM chip to use.
221  * @pcr_idx:	index of the PCR to read.
222  * @res_buf:	buffer to store the resulting hash.
223  *
224  * Return: Same as with tpm_transmit_cmd.
225  */
226 int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
227 {
228 	int rc;
229 	struct tpm_buf buf;
230 	struct tpm2_pcr_read_out *out;
231 	u8 pcr_select[TPM2_PCR_SELECT_MIN] = {0};
232 
233 	if (pcr_idx >= TPM2_PLATFORM_PCR)
234 		return -EINVAL;
235 
236 	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ);
237 	if (rc)
238 		return rc;
239 
240 	pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
241 
242 	tpm_buf_append_u32(&buf, 1);
243 	tpm_buf_append_u16(&buf, TPM2_ALG_SHA1);
244 	tpm_buf_append_u8(&buf, TPM2_PCR_SELECT_MIN);
245 	tpm_buf_append(&buf, (const unsigned char *)pcr_select,
246 		       sizeof(pcr_select));
247 
248 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
249 			res_buf ? "attempting to read a pcr value" : NULL);
250 	if (rc == 0 && res_buf) {
251 		out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE];
252 		memcpy(res_buf, out->digest, SHA1_DIGEST_SIZE);
253 	}
254 
255 	tpm_buf_destroy(&buf);
256 	return rc;
257 }
258 
259 struct tpm2_null_auth_area {
260 	__be32  handle;
261 	__be16  nonce_size;
262 	u8  attributes;
263 	__be16  auth_size;
264 } __packed;
265 
266 /**
267  * tpm2_pcr_extend() - extend a PCR value
268  *
269  * @chip:	TPM chip to use.
270  * @pcr_idx:	index of the PCR.
271  * @count:	number of digests passed.
272  * @digests:	list of pcr banks and corresponding digest values to extend.
273  *
274  * Return: Same as with tpm_transmit_cmd.
275  */
276 int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, u32 count,
277 		    struct tpm2_digest *digests)
278 {
279 	struct tpm_buf buf;
280 	struct tpm2_null_auth_area auth_area;
281 	int rc;
282 	int i;
283 	int j;
284 
285 	if (count > ARRAY_SIZE(chip->active_banks))
286 		return -EINVAL;
287 
288 	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
289 	if (rc)
290 		return rc;
291 
292 	tpm_buf_append_u32(&buf, pcr_idx);
293 
294 	auth_area.handle = cpu_to_be32(TPM2_RS_PW);
295 	auth_area.nonce_size = 0;
296 	auth_area.attributes = 0;
297 	auth_area.auth_size = 0;
298 
299 	tpm_buf_append_u32(&buf, sizeof(struct tpm2_null_auth_area));
300 	tpm_buf_append(&buf, (const unsigned char *)&auth_area,
301 		       sizeof(auth_area));
302 	tpm_buf_append_u32(&buf, count);
303 
304 	for (i = 0; i < count; i++) {
305 		for (j = 0; j < ARRAY_SIZE(tpm2_hash_map); j++) {
306 			if (digests[i].alg_id != tpm2_hash_map[j].tpm_id)
307 				continue;
308 			tpm_buf_append_u16(&buf, digests[i].alg_id);
309 			tpm_buf_append(&buf, (const unsigned char
310 					      *)&digests[i].digest,
311 			       hash_digest_size[tpm2_hash_map[j].crypto_id]);
312 		}
313 	}
314 
315 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
316 			      "attempting extend a PCR value");
317 
318 	tpm_buf_destroy(&buf);
319 
320 	return rc;
321 }
322 
323 
324 #define TPM2_GETRANDOM_IN_SIZE \
325 	(sizeof(struct tpm_input_header) + \
326 	 sizeof(struct tpm2_get_random_in))
327 
328 static const struct tpm_input_header tpm2_getrandom_header = {
329 	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
330 	.length = cpu_to_be32(TPM2_GETRANDOM_IN_SIZE),
331 	.ordinal = cpu_to_be32(TPM2_CC_GET_RANDOM)
332 };
333 
334 /**
335  * tpm2_get_random() - get random bytes from the TPM RNG
336  *
337  * @chip: TPM chip to use
338  * @out: destination buffer for the random bytes
339  * @max: the max number of bytes to write to @out
340  *
341  * Return:
342  *    Size of the output buffer, or -EIO on error.
343  */
344 int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
345 {
346 	struct tpm2_cmd cmd;
347 	u32 recd, rlength;
348 	u32 num_bytes;
349 	int err;
350 	int total = 0;
351 	int retries = 5;
352 	u8 *dest = out;
353 
354 	num_bytes = min_t(u32, max, sizeof(cmd.params.getrandom_out.buffer));
355 
356 	if (!out || !num_bytes ||
357 	    max > sizeof(cmd.params.getrandom_out.buffer))
358 		return -EINVAL;
359 
360 	do {
361 		cmd.header.in = tpm2_getrandom_header;
362 		cmd.params.getrandom_in.size = cpu_to_be16(num_bytes);
363 
364 		err = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd),
365 				       offsetof(struct tpm2_get_random_out,
366 						buffer),
367 				       0, "attempting get random");
368 		if (err)
369 			break;
370 
371 		recd = min_t(u32, be16_to_cpu(cmd.params.getrandom_out.size),
372 			     num_bytes);
373 		rlength = be32_to_cpu(cmd.header.out.length);
374 		if (rlength < offsetof(struct tpm2_get_random_out, buffer) +
375 			      recd)
376 			return -EFAULT;
377 		memcpy(dest, cmd.params.getrandom_out.buffer, recd);
378 
379 		dest += recd;
380 		total += recd;
381 		num_bytes -= recd;
382 	} while (retries-- && total < max);
383 
384 	return total ? total : -EIO;
385 }
386 
387 #define TPM2_GET_TPM_PT_IN_SIZE \
388 	(sizeof(struct tpm_input_header) + \
389 	 sizeof(struct tpm2_get_tpm_pt_in))
390 
391 #define TPM2_GET_TPM_PT_OUT_BODY_SIZE \
392 	 sizeof(struct tpm2_get_tpm_pt_out)
393 
394 static const struct tpm_input_header tpm2_get_tpm_pt_header = {
395 	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
396 	.length = cpu_to_be32(TPM2_GET_TPM_PT_IN_SIZE),
397 	.ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
398 };
399 
400 /**
401  * tpm2_flush_context_cmd() - execute a TPM2_FlushContext command
402  * @chip: TPM chip to use
403  * @payload: the key data in clear and encrypted form
404  * @options: authentication values and other options
405  *
406  * Return: same as with tpm_transmit_cmd
407  */
408 void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
409 			    unsigned int flags)
410 {
411 	struct tpm_buf buf;
412 	int rc;
413 
414 	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
415 	if (rc) {
416 		dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n",
417 			 handle);
418 		return;
419 	}
420 
421 	tpm_buf_append_u32(&buf, handle);
422 
423 	(void) tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, flags,
424 				"flushing context");
425 
426 	tpm_buf_destroy(&buf);
427 }
428 
429 /**
430  * tpm_buf_append_auth() - append TPMS_AUTH_COMMAND to the buffer.
431  *
432  * @buf: an allocated tpm_buf instance
433  * @session_handle: session handle
434  * @nonce: the session nonce, may be NULL if not used
435  * @nonce_len: the session nonce length, may be 0 if not used
436  * @attributes: the session attributes
437  * @hmac: the session HMAC or password, may be NULL if not used
438  * @hmac_len: the session HMAC or password length, maybe 0 if not used
439  */
440 static void tpm2_buf_append_auth(struct tpm_buf *buf, u32 session_handle,
441 				 const u8 *nonce, u16 nonce_len,
442 				 u8 attributes,
443 				 const u8 *hmac, u16 hmac_len)
444 {
445 	tpm_buf_append_u32(buf, 9 + nonce_len + hmac_len);
446 	tpm_buf_append_u32(buf, session_handle);
447 	tpm_buf_append_u16(buf, nonce_len);
448 
449 	if (nonce && nonce_len)
450 		tpm_buf_append(buf, nonce, nonce_len);
451 
452 	tpm_buf_append_u8(buf, attributes);
453 	tpm_buf_append_u16(buf, hmac_len);
454 
455 	if (hmac && hmac_len)
456 		tpm_buf_append(buf, hmac, hmac_len);
457 }
458 
459 /**
460  * tpm2_seal_trusted() - seal the payload of a trusted key
461  *
462  * @chip: TPM chip to use
463  * @payload: the key data in clear and encrypted form
464  * @options: authentication values and other options
465  *
466  * Return: < 0 on error and 0 on success.
467  */
468 int tpm2_seal_trusted(struct tpm_chip *chip,
469 		      struct trusted_key_payload *payload,
470 		      struct trusted_key_options *options)
471 {
472 	unsigned int blob_len;
473 	struct tpm_buf buf;
474 	u32 hash, rlength;
475 	int i;
476 	int rc;
477 
478 	for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {
479 		if (options->hash == tpm2_hash_map[i].crypto_id) {
480 			hash = tpm2_hash_map[i].tpm_id;
481 			break;
482 		}
483 	}
484 
485 	if (i == ARRAY_SIZE(tpm2_hash_map))
486 		return -EINVAL;
487 
488 	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
489 	if (rc)
490 		return rc;
491 
492 	tpm_buf_append_u32(&buf, options->keyhandle);
493 	tpm2_buf_append_auth(&buf, TPM2_RS_PW,
494 			     NULL /* nonce */, 0,
495 			     0 /* session_attributes */,
496 			     options->keyauth /* hmac */,
497 			     TPM_DIGEST_SIZE);
498 
499 	/* sensitive */
500 	tpm_buf_append_u16(&buf, 4 + TPM_DIGEST_SIZE + payload->key_len + 1);
501 
502 	tpm_buf_append_u16(&buf, TPM_DIGEST_SIZE);
503 	tpm_buf_append(&buf, options->blobauth, TPM_DIGEST_SIZE);
504 	tpm_buf_append_u16(&buf, payload->key_len + 1);
505 	tpm_buf_append(&buf, payload->key, payload->key_len);
506 	tpm_buf_append_u8(&buf, payload->migratable);
507 
508 	/* public */
509 	tpm_buf_append_u16(&buf, 14 + options->policydigest_len);
510 	tpm_buf_append_u16(&buf, TPM2_ALG_KEYEDHASH);
511 	tpm_buf_append_u16(&buf, hash);
512 
513 	/* policy */
514 	if (options->policydigest_len) {
515 		tpm_buf_append_u32(&buf, 0);
516 		tpm_buf_append_u16(&buf, options->policydigest_len);
517 		tpm_buf_append(&buf, options->policydigest,
518 			       options->policydigest_len);
519 	} else {
520 		tpm_buf_append_u32(&buf, TPM2_OA_USER_WITH_AUTH);
521 		tpm_buf_append_u16(&buf, 0);
522 	}
523 
524 	/* public parameters */
525 	tpm_buf_append_u16(&buf, TPM2_ALG_NULL);
526 	tpm_buf_append_u16(&buf, 0);
527 
528 	/* outside info */
529 	tpm_buf_append_u16(&buf, 0);
530 
531 	/* creation PCR */
532 	tpm_buf_append_u32(&buf, 0);
533 
534 	if (buf.flags & TPM_BUF_OVERFLOW) {
535 		rc = -E2BIG;
536 		goto out;
537 	}
538 
539 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 4, 0,
540 			      "sealing data");
541 	if (rc)
542 		goto out;
543 
544 	blob_len = be32_to_cpup((__be32 *) &buf.data[TPM_HEADER_SIZE]);
545 	if (blob_len > MAX_BLOB_SIZE) {
546 		rc = -E2BIG;
547 		goto out;
548 	}
549 	rlength = be32_to_cpu(((struct tpm2_cmd *)&buf)->header.out.length);
550 	if (rlength < TPM_HEADER_SIZE + 4 + blob_len) {
551 		rc = -EFAULT;
552 		goto out;
553 	}
554 
555 	memcpy(payload->blob, &buf.data[TPM_HEADER_SIZE + 4], blob_len);
556 	payload->blob_len = blob_len;
557 
558 out:
559 	tpm_buf_destroy(&buf);
560 
561 	if (rc > 0) {
562 		if (tpm2_rc_value(rc) == TPM2_RC_HASH)
563 			rc = -EINVAL;
564 		else
565 			rc = -EPERM;
566 	}
567 
568 	return rc;
569 }
570 
571 /**
572  * tpm2_load_cmd() - execute a TPM2_Load command
573  *
574  * @chip: TPM chip to use
575  * @payload: the key data in clear and encrypted form
576  * @options: authentication values and other options
577  * @blob_handle: returned blob handle
578  * @flags: tpm transmit flags
579  *
580  * Return: 0 on success.
581  *        -E2BIG on wrong payload size.
582  *        -EPERM on tpm error status.
583  *        < 0 error from tpm_transmit_cmd.
584  */
585 static int tpm2_load_cmd(struct tpm_chip *chip,
586 			 struct trusted_key_payload *payload,
587 			 struct trusted_key_options *options,
588 			 u32 *blob_handle, unsigned int flags)
589 {
590 	struct tpm_buf buf;
591 	unsigned int private_len;
592 	unsigned int public_len;
593 	unsigned int blob_len;
594 	int rc;
595 
596 	private_len = be16_to_cpup((__be16 *) &payload->blob[0]);
597 	if (private_len > (payload->blob_len - 2))
598 		return -E2BIG;
599 
600 	public_len = be16_to_cpup((__be16 *) &payload->blob[2 + private_len]);
601 	blob_len = private_len + public_len + 4;
602 	if (blob_len > payload->blob_len)
603 		return -E2BIG;
604 
605 	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
606 	if (rc)
607 		return rc;
608 
609 	tpm_buf_append_u32(&buf, options->keyhandle);
610 	tpm2_buf_append_auth(&buf, TPM2_RS_PW,
611 			     NULL /* nonce */, 0,
612 			     0 /* session_attributes */,
613 			     options->keyauth /* hmac */,
614 			     TPM_DIGEST_SIZE);
615 
616 	tpm_buf_append(&buf, payload->blob, blob_len);
617 
618 	if (buf.flags & TPM_BUF_OVERFLOW) {
619 		rc = -E2BIG;
620 		goto out;
621 	}
622 
623 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 4, flags,
624 			      "loading blob");
625 	if (!rc)
626 		*blob_handle = be32_to_cpup(
627 			(__be32 *) &buf.data[TPM_HEADER_SIZE]);
628 
629 out:
630 	tpm_buf_destroy(&buf);
631 
632 	if (rc > 0)
633 		rc = -EPERM;
634 
635 	return rc;
636 }
637 
638 /**
639  * tpm2_unseal_cmd() - execute a TPM2_Unload command
640  *
641  * @chip: TPM chip to use
642  * @payload: the key data in clear and encrypted form
643  * @options: authentication values and other options
644  * @blob_handle: blob handle
645  * @flags: tpm_transmit_cmd flags
646  *
647  * Return: 0 on success
648  *         -EPERM on tpm error status
649  *         < 0 error from tpm_transmit_cmd
650  */
651 static int tpm2_unseal_cmd(struct tpm_chip *chip,
652 			   struct trusted_key_payload *payload,
653 			   struct trusted_key_options *options,
654 			   u32 blob_handle, unsigned int flags)
655 {
656 	struct tpm_buf buf;
657 	u16 data_len;
658 	u8 *data;
659 	int rc;
660 	u32 rlength;
661 
662 	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
663 	if (rc)
664 		return rc;
665 
666 	tpm_buf_append_u32(&buf, blob_handle);
667 	tpm2_buf_append_auth(&buf,
668 			     options->policyhandle ?
669 			     options->policyhandle : TPM2_RS_PW,
670 			     NULL /* nonce */, 0,
671 			     TPM2_SA_CONTINUE_SESSION,
672 			     options->blobauth /* hmac */,
673 			     TPM_DIGEST_SIZE);
674 
675 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 6, flags,
676 			      "unsealing");
677 	if (rc > 0)
678 		rc = -EPERM;
679 
680 	if (!rc) {
681 		data_len = be16_to_cpup(
682 			(__be16 *) &buf.data[TPM_HEADER_SIZE + 4]);
683 		if (data_len < MIN_KEY_SIZE ||  data_len > MAX_KEY_SIZE + 1) {
684 			rc = -EFAULT;
685 			goto out;
686 		}
687 
688 		rlength = be32_to_cpu(((struct tpm2_cmd *)&buf)
689 					->header.out.length);
690 		if (rlength < TPM_HEADER_SIZE + 6 + data_len) {
691 			rc = -EFAULT;
692 			goto out;
693 		}
694 		data = &buf.data[TPM_HEADER_SIZE + 6];
695 
696 		memcpy(payload->key, data, data_len - 1);
697 		payload->key_len = data_len - 1;
698 		payload->migratable = data[data_len - 1];
699 	}
700 
701 out:
702 	tpm_buf_destroy(&buf);
703 	return rc;
704 }
705 
706 /**
707  * tpm2_unseal_trusted() - unseal the payload of a trusted key
708  *
709  * @chip: TPM chip to use
710  * @payload: the key data in clear and encrypted form
711  * @options: authentication values and other options
712  *
713  * Return: Same as with tpm_transmit_cmd.
714  */
715 int tpm2_unseal_trusted(struct tpm_chip *chip,
716 			struct trusted_key_payload *payload,
717 			struct trusted_key_options *options)
718 {
719 	u32 blob_handle;
720 	int rc;
721 
722 	mutex_lock(&chip->tpm_mutex);
723 	rc = tpm2_load_cmd(chip, payload, options, &blob_handle,
724 			   TPM_TRANSMIT_UNLOCKED);
725 	if (rc)
726 		goto out;
727 
728 	rc = tpm2_unseal_cmd(chip, payload, options, blob_handle,
729 			     TPM_TRANSMIT_UNLOCKED);
730 	tpm2_flush_context_cmd(chip, blob_handle, TPM_TRANSMIT_UNLOCKED);
731 out:
732 	mutex_unlock(&chip->tpm_mutex);
733 	return rc;
734 }
735 
736 /**
737  * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
738  * @chip:		TPM chip to use.
739  * @property_id:	property ID.
740  * @value:		output variable.
741  * @desc:		passed to tpm_transmit_cmd()
742  *
743  * Return: Same as with tpm_transmit_cmd.
744  */
745 ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
746 			const char *desc)
747 {
748 	struct tpm2_cmd cmd;
749 	int rc;
750 
751 	cmd.header.in = tpm2_get_tpm_pt_header;
752 	cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
753 	cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(property_id);
754 	cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
755 
756 	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd),
757 			      TPM2_GET_TPM_PT_OUT_BODY_SIZE, 0, desc);
758 	if (!rc)
759 		*value = be32_to_cpu(cmd.params.get_tpm_pt_out.value);
760 
761 	return rc;
762 }
763 EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
764 
765 #define TPM2_SHUTDOWN_IN_SIZE \
766 	(sizeof(struct tpm_input_header) + \
767 	 sizeof(struct tpm2_startup_in))
768 
769 static const struct tpm_input_header tpm2_shutdown_header = {
770 	.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
771 	.length = cpu_to_be32(TPM2_SHUTDOWN_IN_SIZE),
772 	.ordinal = cpu_to_be32(TPM2_CC_SHUTDOWN)
773 };
774 
775 /**
776  * tpm2_shutdown() - send shutdown command to the TPM chip
777  *
778  * @chip:		TPM chip to use.
779  * @shutdown_type:	shutdown type. The value is either
780  *			TPM_SU_CLEAR or TPM_SU_STATE.
781  */
782 void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
783 {
784 	struct tpm2_cmd cmd;
785 	int rc;
786 
787 	cmd.header.in = tpm2_shutdown_header;
788 	cmd.params.startup_in.startup_type = cpu_to_be16(shutdown_type);
789 
790 	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0,
791 			      "stopping the TPM");
792 
793 	/* In places where shutdown command is sent there's no much we can do
794 	 * except print the error code on a system failure.
795 	 */
796 	if (rc < 0 && rc != -EPIPE)
797 		dev_warn(&chip->dev, "transmit returned %d while stopping the TPM",
798 			 rc);
799 }
800 
801 /*
802  * tpm2_calc_ordinal_duration() - maximum duration for a command
803  *
804  * @chip:	TPM chip to use.
805  * @ordinal:	command code number.
806  *
807  * Return: maximum duration for a command
808  */
809 unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
810 {
811 	int index = TPM_UNDEFINED;
812 	int duration = 0;
813 
814 	if (ordinal >= TPM2_CC_FIRST && ordinal <= TPM2_CC_LAST)
815 		index = tpm2_ordinal_duration[ordinal - TPM2_CC_FIRST];
816 
817 	if (index != TPM_UNDEFINED)
818 		duration = chip->duration[index];
819 
820 	if (duration <= 0)
821 		duration = msecs_to_jiffies(TPM2_DURATION_DEFAULT);
822 
823 	return duration;
824 }
825 EXPORT_SYMBOL_GPL(tpm2_calc_ordinal_duration);
826 
827 /**
828  * tpm2_do_selftest() - ensure that all self tests have passed
829  *
830  * @chip: TPM chip to use
831  *
832  * Return: Same as with tpm_transmit_cmd.
833  *
834  * The TPM can either run all self tests synchronously and then return
835  * RC_SUCCESS once all tests were successful. Or it can choose to run the tests
836  * asynchronously and return RC_TESTING immediately while the self tests still
837  * execute in the background. This function handles both cases and waits until
838  * all tests have completed.
839  */
840 static int tpm2_do_selftest(struct tpm_chip *chip)
841 {
842 	struct tpm_buf buf;
843 	int full;
844 	int rc;
845 
846 	for (full = 0; full < 2; full++) {
847 		rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SELF_TEST);
848 		if (rc)
849 			return rc;
850 
851 		tpm_buf_append_u8(&buf, full);
852 		rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
853 				      "attempting the self test");
854 		tpm_buf_destroy(&buf);
855 
856 		if (rc == TPM2_RC_TESTING)
857 			rc = TPM2_RC_SUCCESS;
858 		if (rc == TPM2_RC_INITIALIZE || rc == TPM2_RC_SUCCESS)
859 			return rc;
860 	}
861 
862 	return rc;
863 }
864 
865 /**
866  * tpm2_probe() - probe TPM 2.0
867  * @chip: TPM chip to use
868  *
869  * Return: < 0 error and 0 on success.
870  *
871  * Send idempotent TPM 2.0 command and see whether TPM 2.0 chip replied based on
872  * the reply tag.
873  */
874 int tpm2_probe(struct tpm_chip *chip)
875 {
876 	struct tpm2_cmd cmd;
877 	int rc;
878 
879 	cmd.header.in = tpm2_get_tpm_pt_header;
880 	cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
881 	cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(0x100);
882 	cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
883 
884 	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0, NULL);
885 	if (rc <  0)
886 		return rc;
887 
888 	if (be16_to_cpu(cmd.header.out.tag) == TPM2_ST_NO_SESSIONS)
889 		chip->flags |= TPM_CHIP_FLAG_TPM2;
890 
891 	return 0;
892 }
893 EXPORT_SYMBOL_GPL(tpm2_probe);
894 
895 struct tpm2_pcr_selection {
896 	__be16  hash_alg;
897 	u8  size_of_select;
898 	u8  pcr_select[3];
899 } __packed;
900 
901 static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
902 {
903 	struct tpm2_pcr_selection pcr_selection;
904 	struct tpm_buf buf;
905 	void *marker;
906 	void *end;
907 	void *pcr_select_offset;
908 	unsigned int count;
909 	u32 sizeof_pcr_selection;
910 	u32 rsp_len;
911 	int rc;
912 	int i = 0;
913 
914 	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
915 	if (rc)
916 		return rc;
917 
918 	tpm_buf_append_u32(&buf, TPM2_CAP_PCRS);
919 	tpm_buf_append_u32(&buf, 0);
920 	tpm_buf_append_u32(&buf, 1);
921 
922 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 9, 0,
923 			      "get tpm pcr allocation");
924 	if (rc)
925 		goto out;
926 
927 	count = be32_to_cpup(
928 		(__be32 *)&buf.data[TPM_HEADER_SIZE + 5]);
929 
930 	if (count > ARRAY_SIZE(chip->active_banks)) {
931 		rc = -ENODEV;
932 		goto out;
933 	}
934 
935 	marker = &buf.data[TPM_HEADER_SIZE + 9];
936 
937 	rsp_len = be32_to_cpup((__be32 *)&buf.data[2]);
938 	end = &buf.data[rsp_len];
939 
940 	for (i = 0; i < count; i++) {
941 		pcr_select_offset = marker +
942 			offsetof(struct tpm2_pcr_selection, size_of_select);
943 		if (pcr_select_offset >= end) {
944 			rc = -EFAULT;
945 			break;
946 		}
947 
948 		memcpy(&pcr_selection, marker, sizeof(pcr_selection));
949 		chip->active_banks[i] = be16_to_cpu(pcr_selection.hash_alg);
950 		sizeof_pcr_selection = sizeof(pcr_selection.hash_alg) +
951 			sizeof(pcr_selection.size_of_select) +
952 			pcr_selection.size_of_select;
953 		marker = marker + sizeof_pcr_selection;
954 	}
955 
956 out:
957 	if (i < ARRAY_SIZE(chip->active_banks))
958 		chip->active_banks[i] = TPM2_ALG_ERROR;
959 
960 	tpm_buf_destroy(&buf);
961 
962 	return rc;
963 }
964 
965 static int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
966 {
967 	struct tpm_buf buf;
968 	u32 nr_commands;
969 	__be32 *attrs;
970 	u32 cc;
971 	int i;
972 	int rc;
973 
974 	rc = tpm2_get_tpm_pt(chip, TPM_PT_TOTAL_COMMANDS, &nr_commands, NULL);
975 	if (rc)
976 		goto out;
977 
978 	if (nr_commands > 0xFFFFF) {
979 		rc = -EFAULT;
980 		goto out;
981 	}
982 
983 	chip->cc_attrs_tbl = devm_kzalloc(&chip->dev, 4 * nr_commands,
984 					  GFP_KERNEL);
985 
986 	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
987 	if (rc)
988 		goto out;
989 
990 	tpm_buf_append_u32(&buf, TPM2_CAP_COMMANDS);
991 	tpm_buf_append_u32(&buf, TPM2_CC_FIRST);
992 	tpm_buf_append_u32(&buf, nr_commands);
993 
994 	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE,
995 			      9 + 4 * nr_commands, 0, NULL);
996 	if (rc) {
997 		tpm_buf_destroy(&buf);
998 		goto out;
999 	}
1000 
1001 	if (nr_commands !=
1002 	    be32_to_cpup((__be32 *)&buf.data[TPM_HEADER_SIZE + 5])) {
1003 		tpm_buf_destroy(&buf);
1004 		goto out;
1005 	}
1006 
1007 	chip->nr_commands = nr_commands;
1008 
1009 	attrs = (__be32 *)&buf.data[TPM_HEADER_SIZE + 9];
1010 	for (i = 0; i < nr_commands; i++, attrs++) {
1011 		chip->cc_attrs_tbl[i] = be32_to_cpup(attrs);
1012 		cc = chip->cc_attrs_tbl[i] & 0xFFFF;
1013 
1014 		if (cc == TPM2_CC_CONTEXT_SAVE || cc == TPM2_CC_FLUSH_CONTEXT) {
1015 			chip->cc_attrs_tbl[i] &=
1016 				~(GENMASK(2, 0) << TPM2_CC_ATTR_CHANDLES);
1017 			chip->cc_attrs_tbl[i] |= 1 << TPM2_CC_ATTR_CHANDLES;
1018 		}
1019 	}
1020 
1021 	tpm_buf_destroy(&buf);
1022 
1023 out:
1024 	if (rc > 0)
1025 		rc = -ENODEV;
1026 	return rc;
1027 }
1028 
1029 /**
1030  * tpm2_auto_startup - Perform the standard automatic TPM initialization
1031  *                     sequence
1032  * @chip: TPM chip to use
1033  *
1034  * Returns 0 on success, < 0 in case of fatal error.
1035  */
1036 int tpm2_auto_startup(struct tpm_chip *chip)
1037 {
1038 	int rc;
1039 
1040 	rc = tpm_get_timeouts(chip);
1041 	if (rc)
1042 		goto out;
1043 
1044 	rc = tpm2_do_selftest(chip);
1045 	if (rc && rc != TPM2_RC_INITIALIZE)
1046 		goto out;
1047 
1048 	if (rc == TPM2_RC_INITIALIZE) {
1049 		rc = tpm_startup(chip);
1050 		if (rc)
1051 			goto out;
1052 
1053 		rc = tpm2_do_selftest(chip);
1054 		if (rc)
1055 			goto out;
1056 	}
1057 
1058 	rc = tpm2_get_pcr_allocation(chip);
1059 	if (rc)
1060 		goto out;
1061 
1062 	rc = tpm2_get_cc_attrs_tbl(chip);
1063 
1064 out:
1065 	if (rc > 0)
1066 		rc = -ENODEV;
1067 	return rc;
1068 }
1069 
1070 int tpm2_find_cc(struct tpm_chip *chip, u32 cc)
1071 {
1072 	int i;
1073 
1074 	for (i = 0; i < chip->nr_commands; i++)
1075 		if (cc == (chip->cc_attrs_tbl[i] & GENMASK(15, 0)))
1076 			return i;
1077 
1078 	return -1;
1079 }
1080