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v6.8
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) 2014, 2015 Intel Corporation
  4 *
  5 * Authors:
  6 * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
  7 *
  8 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
  9 *
 10 * This file contains TPM2 protocol implementations of the commands
 11 * used by the kernel internally.
 12 */
 13
 14#include "tpm.h"
 15#include <crypto/hash_info.h>
 16
 
 
 
 
 17static struct tpm2_hash tpm2_hash_map[] = {
 18	{HASH_ALGO_SHA1, TPM_ALG_SHA1},
 19	{HASH_ALGO_SHA256, TPM_ALG_SHA256},
 20	{HASH_ALGO_SHA384, TPM_ALG_SHA384},
 21	{HASH_ALGO_SHA512, TPM_ALG_SHA512},
 22	{HASH_ALGO_SM3_256, TPM_ALG_SM3_256},
 23};
 24
 25int tpm2_get_timeouts(struct tpm_chip *chip)
 26{
 27	/* Fixed timeouts for TPM2 */
 28	chip->timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
 29	chip->timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
 30	chip->timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
 31	chip->timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
 32
 33	/* PTP spec timeouts */
 34	chip->duration[TPM_SHORT] = msecs_to_jiffies(TPM2_DURATION_SHORT);
 35	chip->duration[TPM_MEDIUM] = msecs_to_jiffies(TPM2_DURATION_MEDIUM);
 36	chip->duration[TPM_LONG] = msecs_to_jiffies(TPM2_DURATION_LONG);
 37
 38	/* Key creation commands long timeouts */
 39	chip->duration[TPM_LONG_LONG] =
 40		msecs_to_jiffies(TPM2_DURATION_LONG_LONG);
 41
 42	chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
 43
 44	return 0;
 45}
 46
 47/**
 48 * tpm2_ordinal_duration_index() - returns an index to the chip duration table
 49 * @ordinal: TPM command ordinal.
 50 *
 51 * The function returns an index to the chip duration table
 52 * (enum tpm_duration), that describes the maximum amount of
 53 * time the chip could take to return the result for a  particular ordinal.
 54 *
 55 * The values of the MEDIUM, and LONG durations are taken
 56 * from the PC Client Profile (PTP) specification (750, 2000 msec)
 57 *
 58 * LONG_LONG is for commands that generates keys which empirically takes
 59 * a longer time on some systems.
 60 *
 61 * Return:
 62 * * TPM_MEDIUM
 63 * * TPM_LONG
 64 * * TPM_LONG_LONG
 65 * * TPM_UNDEFINED
 66 */
 67static u8 tpm2_ordinal_duration_index(u32 ordinal)
 68{
 69	switch (ordinal) {
 70	/* Startup */
 71	case TPM2_CC_STARTUP:                 /* 144 */
 72		return TPM_MEDIUM;
 73
 74	case TPM2_CC_SELF_TEST:               /* 143 */
 75		return TPM_LONG;
 76
 77	case TPM2_CC_GET_RANDOM:              /* 17B */
 78		return TPM_LONG;
 79
 80	case TPM2_CC_SEQUENCE_UPDATE:         /* 15C */
 81		return TPM_MEDIUM;
 82	case TPM2_CC_SEQUENCE_COMPLETE:       /* 13E */
 83		return TPM_MEDIUM;
 84	case TPM2_CC_EVENT_SEQUENCE_COMPLETE: /* 185 */
 85		return TPM_MEDIUM;
 86	case TPM2_CC_HASH_SEQUENCE_START:     /* 186 */
 87		return TPM_MEDIUM;
 88
 89	case TPM2_CC_VERIFY_SIGNATURE:        /* 177 */
 90		return TPM_LONG_LONG;
 91
 92	case TPM2_CC_PCR_EXTEND:              /* 182 */
 93		return TPM_MEDIUM;
 94
 95	case TPM2_CC_HIERARCHY_CONTROL:       /* 121 */
 96		return TPM_LONG;
 97	case TPM2_CC_HIERARCHY_CHANGE_AUTH:   /* 129 */
 98		return TPM_LONG;
 99
100	case TPM2_CC_GET_CAPABILITY:          /* 17A */
101		return TPM_MEDIUM;
102
103	case TPM2_CC_NV_READ:                 /* 14E */
104		return TPM_LONG;
105
106	case TPM2_CC_CREATE_PRIMARY:          /* 131 */
107		return TPM_LONG_LONG;
108	case TPM2_CC_CREATE:                  /* 153 */
109		return TPM_LONG_LONG;
110	case TPM2_CC_CREATE_LOADED:           /* 191 */
111		return TPM_LONG_LONG;
112
113	default:
114		return TPM_UNDEFINED;
115	}
116}
117
118/**
119 * tpm2_calc_ordinal_duration() - calculate the maximum command duration
120 * @chip:    TPM chip to use.
121 * @ordinal: TPM command ordinal.
122 *
123 * The function returns the maximum amount of time the chip could take
124 * to return the result for a particular ordinal in jiffies.
125 *
126 * Return: A maximal duration time for an ordinal in jiffies.
127 */
128unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
129{
130	unsigned int index;
131
132	index = tpm2_ordinal_duration_index(ordinal);
133
134	if (index != TPM_UNDEFINED)
135		return chip->duration[index];
136	else
137		return msecs_to_jiffies(TPM2_DURATION_DEFAULT);
138}
139
140
141struct tpm2_pcr_read_out {
142	__be32	update_cnt;
143	__be32	pcr_selects_cnt;
144	__be16	hash_alg;
145	u8	pcr_select_size;
146	u8	pcr_select[TPM2_PCR_SELECT_MIN];
147	__be32	digests_cnt;
148	__be16	digest_size;
149	u8	digest[];
150} __packed;
151
152/**
153 * tpm2_pcr_read() - read a PCR value
154 * @chip:	TPM chip to use.
155 * @pcr_idx:	index of the PCR to read.
156 * @digest:	PCR bank and buffer current PCR value is written to.
157 * @digest_size_ptr:	pointer to variable that stores the digest size.
158 *
159 * Return: Same as with tpm_transmit_cmd.
160 */
161int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
162		  struct tpm_digest *digest, u16 *digest_size_ptr)
163{
164	int i;
165	int rc;
166	struct tpm_buf buf;
167	struct tpm2_pcr_read_out *out;
168	u8 pcr_select[TPM2_PCR_SELECT_MIN] = {0};
169	u16 digest_size;
170	u16 expected_digest_size = 0;
171
172	if (pcr_idx >= TPM2_PLATFORM_PCR)
173		return -EINVAL;
174
175	if (!digest_size_ptr) {
176		for (i = 0; i < chip->nr_allocated_banks &&
177		     chip->allocated_banks[i].alg_id != digest->alg_id; i++)
178			;
179
180		if (i == chip->nr_allocated_banks)
181			return -EINVAL;
182
183		expected_digest_size = chip->allocated_banks[i].digest_size;
184	}
185
186	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ);
187	if (rc)
188		return rc;
189
190	pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
191
192	tpm_buf_append_u32(&buf, 1);
193	tpm_buf_append_u16(&buf, digest->alg_id);
194	tpm_buf_append_u8(&buf, TPM2_PCR_SELECT_MIN);
195	tpm_buf_append(&buf, (const unsigned char *)pcr_select,
196		       sizeof(pcr_select));
197
198	rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to read a pcr value");
199	if (rc)
200		goto out;
201
202	out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE];
203	digest_size = be16_to_cpu(out->digest_size);
204	if (digest_size > sizeof(digest->digest) ||
205	    (!digest_size_ptr && digest_size != expected_digest_size)) {
206		rc = -EINVAL;
207		goto out;
208	}
209
210	if (digest_size_ptr)
211		*digest_size_ptr = digest_size;
212
213	memcpy(digest->digest, out->digest, digest_size);
214out:
215	tpm_buf_destroy(&buf);
216	return rc;
217}
218
219struct tpm2_null_auth_area {
220	__be32  handle;
221	__be16  nonce_size;
222	u8  attributes;
223	__be16  auth_size;
224} __packed;
225
226/**
227 * tpm2_pcr_extend() - extend a PCR value
228 *
229 * @chip:	TPM chip to use.
230 * @pcr_idx:	index of the PCR.
231 * @digests:	list of pcr banks and corresponding digest values to extend.
232 *
233 * Return: Same as with tpm_transmit_cmd.
234 */
235int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
236		    struct tpm_digest *digests)
237{
238	struct tpm_buf buf;
239	struct tpm2_null_auth_area auth_area;
240	int rc;
241	int i;
242
 
 
 
 
 
 
243	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
244	if (rc)
 
 
245		return rc;
 
246
247	tpm_buf_append_u32(&buf, pcr_idx);
 
 
 
 
 
 
248
249	auth_area.handle = cpu_to_be32(TPM2_RS_PW);
250	auth_area.nonce_size = 0;
251	auth_area.attributes = 0;
252	auth_area.auth_size = 0;
253
254	tpm_buf_append_u32(&buf, sizeof(struct tpm2_null_auth_area));
255	tpm_buf_append(&buf, (const unsigned char *)&auth_area,
256		       sizeof(auth_area));
257	tpm_buf_append_u32(&buf, chip->nr_allocated_banks);
258
259	for (i = 0; i < chip->nr_allocated_banks; i++) {
260		tpm_buf_append_u16(&buf, digests[i].alg_id);
261		tpm_buf_append(&buf, (const unsigned char *)&digests[i].digest,
262			       chip->allocated_banks[i].digest_size);
263	}
264
 
 
265	rc = tpm_transmit_cmd(chip, &buf, 0, "attempting extend a PCR value");
 
 
266
267	tpm_buf_destroy(&buf);
268
269	return rc;
270}
271
272struct tpm2_get_random_out {
273	__be16 size;
274	u8 buffer[TPM_MAX_RNG_DATA];
275} __packed;
276
277/**
278 * tpm2_get_random() - get random bytes from the TPM RNG
279 *
280 * @chip:	a &tpm_chip instance
281 * @dest:	destination buffer
282 * @max:	the max number of random bytes to pull
283 *
284 * Return:
285 *   size of the buffer on success,
286 *   -errno otherwise (positive TPM return codes are masked to -EIO)
287 */
288int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
289{
290	struct tpm2_get_random_out *out;
 
291	struct tpm_buf buf;
292	u32 recd;
293	u32 num_bytes = max;
294	int err;
295	int total = 0;
296	int retries = 5;
297	u8 *dest_ptr = dest;
 
298
299	if (!num_bytes || max > TPM_MAX_RNG_DATA)
300		return -EINVAL;
301
302	err = tpm_buf_init(&buf, 0, 0);
303	if (err)
304		return err;
305
 
 
 
 
 
 
306	do {
307		tpm_buf_reset(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_RANDOM);
 
 
 
308		tpm_buf_append_u16(&buf, num_bytes);
 
309		err = tpm_transmit_cmd(chip, &buf,
310				       offsetof(struct tpm2_get_random_out,
311						buffer),
312				       "attempting get random");
 
313		if (err) {
314			if (err > 0)
315				err = -EIO;
316			goto out;
317		}
318
319		out = (struct tpm2_get_random_out *)
320			&buf.data[TPM_HEADER_SIZE];
 
 
 
 
 
321		recd = min_t(u32, be16_to_cpu(out->size), num_bytes);
322		if (tpm_buf_length(&buf) <
323		    TPM_HEADER_SIZE +
324		    offsetof(struct tpm2_get_random_out, buffer) +
325		    recd) {
326			err = -EFAULT;
327			goto out;
328		}
329		memcpy(dest_ptr, out->buffer, recd);
330
331		dest_ptr += recd;
332		total += recd;
333		num_bytes -= recd;
334	} while (retries-- && total < max);
335
336	tpm_buf_destroy(&buf);
 
 
337	return total ? total : -EIO;
338out:
339	tpm_buf_destroy(&buf);
 
340	return err;
341}
342
343/**
344 * tpm2_flush_context() - execute a TPM2_FlushContext command
345 * @chip:	TPM chip to use
346 * @handle:	context handle
347 */
348void tpm2_flush_context(struct tpm_chip *chip, u32 handle)
349{
350	struct tpm_buf buf;
351	int rc;
352
353	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
354	if (rc) {
355		dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n",
356			 handle);
357		return;
358	}
359
360	tpm_buf_append_u32(&buf, handle);
361
362	tpm_transmit_cmd(chip, &buf, 0, "flushing context");
363	tpm_buf_destroy(&buf);
364}
365EXPORT_SYMBOL_GPL(tpm2_flush_context);
366
367struct tpm2_get_cap_out {
368	u8 more_data;
369	__be32 subcap_id;
370	__be32 property_cnt;
371	__be32 property_id;
372	__be32 value;
373} __packed;
374
375/**
376 * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
377 * @chip:		a &tpm_chip instance
378 * @property_id:	property ID.
379 * @value:		output variable.
380 * @desc:		passed to tpm_transmit_cmd()
381 *
382 * Return:
383 *   0 on success,
384 *   -errno or a TPM return code otherwise
385 */
386ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
387			const char *desc)
388{
389	struct tpm2_get_cap_out *out;
390	struct tpm_buf buf;
391	int rc;
392
393	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
394	if (rc)
395		return rc;
396	tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
397	tpm_buf_append_u32(&buf, property_id);
398	tpm_buf_append_u32(&buf, 1);
399	rc = tpm_transmit_cmd(chip, &buf, 0, NULL);
400	if (!rc) {
401		out = (struct tpm2_get_cap_out *)
402			&buf.data[TPM_HEADER_SIZE];
403		/*
404		 * To prevent failing boot up of some systems, Infineon TPM2.0
405		 * returns SUCCESS on TPM2_Startup in field upgrade mode. Also
406		 * the TPM2_Getcapability command returns a zero length list
407		 * in field upgrade mode.
408		 */
409		if (be32_to_cpu(out->property_cnt) > 0)
410			*value = be32_to_cpu(out->value);
411		else
412			rc = -ENODATA;
413	}
414	tpm_buf_destroy(&buf);
415	return rc;
416}
417EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
418
419/**
420 * tpm2_shutdown() - send a TPM shutdown command
421 *
422 * Sends a TPM shutdown command. The shutdown command is used in call
423 * sites where the system is going down. If it fails, there is not much
424 * that can be done except print an error message.
425 *
426 * @chip:		a &tpm_chip instance
427 * @shutdown_type:	TPM_SU_CLEAR or TPM_SU_STATE.
428 */
429void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
430{
431	struct tpm_buf buf;
432	int rc;
433
434	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SHUTDOWN);
435	if (rc)
436		return;
437	tpm_buf_append_u16(&buf, shutdown_type);
438	tpm_transmit_cmd(chip, &buf, 0, "stopping the TPM");
439	tpm_buf_destroy(&buf);
440}
441
442/**
443 * tpm2_do_selftest() - ensure that all self tests have passed
444 *
445 * @chip: TPM chip to use
446 *
447 * Return: Same as with tpm_transmit_cmd.
448 *
449 * The TPM can either run all self tests synchronously and then return
450 * RC_SUCCESS once all tests were successful. Or it can choose to run the tests
451 * asynchronously and return RC_TESTING immediately while the self tests still
452 * execute in the background. This function handles both cases and waits until
453 * all tests have completed.
454 */
455static int tpm2_do_selftest(struct tpm_chip *chip)
456{
457	struct tpm_buf buf;
458	int full;
459	int rc;
460
461	for (full = 0; full < 2; full++) {
462		rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SELF_TEST);
463		if (rc)
464			return rc;
465
466		tpm_buf_append_u8(&buf, full);
467		rc = tpm_transmit_cmd(chip, &buf, 0,
468				      "attempting the self test");
469		tpm_buf_destroy(&buf);
470
471		if (rc == TPM2_RC_TESTING)
472			rc = TPM2_RC_SUCCESS;
473		if (rc == TPM2_RC_INITIALIZE || rc == TPM2_RC_SUCCESS)
474			return rc;
475	}
476
477	return rc;
478}
479
480/**
481 * tpm2_probe() - probe for the TPM 2.0 protocol
482 * @chip:	a &tpm_chip instance
483 *
484 * Send an idempotent TPM 2.0 command and see whether there is TPM2 chip in the
485 * other end based on the response tag. The flag TPM_CHIP_FLAG_TPM2 is set by
486 * this function if this is the case.
487 *
488 * Return:
489 *   0 on success,
490 *   -errno otherwise
491 */
492int tpm2_probe(struct tpm_chip *chip)
493{
494	struct tpm_header *out;
495	struct tpm_buf buf;
496	int rc;
497
498	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
499	if (rc)
500		return rc;
501	tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
502	tpm_buf_append_u32(&buf, TPM_PT_TOTAL_COMMANDS);
503	tpm_buf_append_u32(&buf, 1);
504	rc = tpm_transmit_cmd(chip, &buf, 0, NULL);
505	/* We ignore TPM return codes on purpose. */
506	if (rc >=  0) {
507		out = (struct tpm_header *)buf.data;
508		if (be16_to_cpu(out->tag) == TPM2_ST_NO_SESSIONS)
509			chip->flags |= TPM_CHIP_FLAG_TPM2;
510	}
511	tpm_buf_destroy(&buf);
512	return 0;
513}
514EXPORT_SYMBOL_GPL(tpm2_probe);
515
516static int tpm2_init_bank_info(struct tpm_chip *chip, u32 bank_index)
517{
518	struct tpm_bank_info *bank = chip->allocated_banks + bank_index;
519	struct tpm_digest digest = { .alg_id = bank->alg_id };
520	int i;
521
522	/*
523	 * Avoid unnecessary PCR read operations to reduce overhead
524	 * and obtain identifiers of the crypto subsystem.
525	 */
526	for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {
527		enum hash_algo crypto_algo = tpm2_hash_map[i].crypto_id;
528
529		if (bank->alg_id != tpm2_hash_map[i].tpm_id)
530			continue;
531
532		bank->digest_size = hash_digest_size[crypto_algo];
533		bank->crypto_id = crypto_algo;
534		return 0;
535	}
536
537	bank->crypto_id = HASH_ALGO__LAST;
538
539	return tpm2_pcr_read(chip, 0, &digest, &bank->digest_size);
540}
541
542struct tpm2_pcr_selection {
543	__be16  hash_alg;
544	u8  size_of_select;
545	u8  pcr_select[3];
546} __packed;
547
548ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
549{
550	struct tpm2_pcr_selection pcr_selection;
551	struct tpm_buf buf;
552	void *marker;
553	void *end;
554	void *pcr_select_offset;
555	u32 sizeof_pcr_selection;
556	u32 nr_possible_banks;
557	u32 nr_alloc_banks = 0;
558	u16 hash_alg;
559	u32 rsp_len;
560	int rc;
561	int i = 0;
562
563	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
564	if (rc)
565		return rc;
566
567	tpm_buf_append_u32(&buf, TPM2_CAP_PCRS);
568	tpm_buf_append_u32(&buf, 0);
569	tpm_buf_append_u32(&buf, 1);
570
571	rc = tpm_transmit_cmd(chip, &buf, 9, "get tpm pcr allocation");
572	if (rc)
573		goto out;
574
575	nr_possible_banks = be32_to_cpup(
576		(__be32 *)&buf.data[TPM_HEADER_SIZE + 5]);
577
578	chip->allocated_banks = kcalloc(nr_possible_banks,
579					sizeof(*chip->allocated_banks),
580					GFP_KERNEL);
581	if (!chip->allocated_banks) {
582		rc = -ENOMEM;
583		goto out;
584	}
585
586	marker = &buf.data[TPM_HEADER_SIZE + 9];
587
588	rsp_len = be32_to_cpup((__be32 *)&buf.data[2]);
589	end = &buf.data[rsp_len];
590
591	for (i = 0; i < nr_possible_banks; i++) {
592		pcr_select_offset = marker +
593			offsetof(struct tpm2_pcr_selection, size_of_select);
594		if (pcr_select_offset >= end) {
595			rc = -EFAULT;
596			break;
597		}
598
599		memcpy(&pcr_selection, marker, sizeof(pcr_selection));
600		hash_alg = be16_to_cpu(pcr_selection.hash_alg);
601
602		pcr_select_offset = memchr_inv(pcr_selection.pcr_select, 0,
603					       pcr_selection.size_of_select);
604		if (pcr_select_offset) {
605			chip->allocated_banks[nr_alloc_banks].alg_id = hash_alg;
606
607			rc = tpm2_init_bank_info(chip, nr_alloc_banks);
608			if (rc < 0)
609				break;
610
611			nr_alloc_banks++;
612		}
613
614		sizeof_pcr_selection = sizeof(pcr_selection.hash_alg) +
615			sizeof(pcr_selection.size_of_select) +
616			pcr_selection.size_of_select;
617		marker = marker + sizeof_pcr_selection;
618	}
619
620	chip->nr_allocated_banks = nr_alloc_banks;
621out:
622	tpm_buf_destroy(&buf);
623
624	return rc;
625}
626
627int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
628{
629	struct tpm_buf buf;
630	u32 nr_commands;
631	__be32 *attrs;
632	u32 cc;
633	int i;
634	int rc;
635
636	rc = tpm2_get_tpm_pt(chip, TPM_PT_TOTAL_COMMANDS, &nr_commands, NULL);
637	if (rc)
638		goto out;
639
640	if (nr_commands > 0xFFFFF) {
641		rc = -EFAULT;
642		goto out;
643	}
644
645	chip->cc_attrs_tbl = devm_kcalloc(&chip->dev, 4, nr_commands,
646					  GFP_KERNEL);
647	if (!chip->cc_attrs_tbl) {
648		rc = -ENOMEM;
649		goto out;
650	}
651
652	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
653	if (rc)
654		goto out;
655
656	tpm_buf_append_u32(&buf, TPM2_CAP_COMMANDS);
657	tpm_buf_append_u32(&buf, TPM2_CC_FIRST);
658	tpm_buf_append_u32(&buf, nr_commands);
659
660	rc = tpm_transmit_cmd(chip, &buf, 9 + 4 * nr_commands, NULL);
661	if (rc) {
662		tpm_buf_destroy(&buf);
663		goto out;
664	}
665
666	if (nr_commands !=
667	    be32_to_cpup((__be32 *)&buf.data[TPM_HEADER_SIZE + 5])) {
668		rc = -EFAULT;
669		tpm_buf_destroy(&buf);
670		goto out;
671	}
672
673	chip->nr_commands = nr_commands;
674
675	attrs = (__be32 *)&buf.data[TPM_HEADER_SIZE + 9];
676	for (i = 0; i < nr_commands; i++, attrs++) {
677		chip->cc_attrs_tbl[i] = be32_to_cpup(attrs);
678		cc = chip->cc_attrs_tbl[i] & 0xFFFF;
679
680		if (cc == TPM2_CC_CONTEXT_SAVE || cc == TPM2_CC_FLUSH_CONTEXT) {
681			chip->cc_attrs_tbl[i] &=
682				~(GENMASK(2, 0) << TPM2_CC_ATTR_CHANDLES);
683			chip->cc_attrs_tbl[i] |= 1 << TPM2_CC_ATTR_CHANDLES;
684		}
685	}
686
687	tpm_buf_destroy(&buf);
688
689out:
690	if (rc > 0)
691		rc = -ENODEV;
692	return rc;
693}
694EXPORT_SYMBOL_GPL(tpm2_get_cc_attrs_tbl);
695
696/**
697 * tpm2_startup - turn on the TPM
698 * @chip: TPM chip to use
699 *
700 * Normally the firmware should start the TPM. This function is provided as a
701 * workaround if this does not happen. A legal case for this could be for
702 * example when a TPM emulator is used.
703 *
704 * Return: same as tpm_transmit_cmd()
705 */
706
707static int tpm2_startup(struct tpm_chip *chip)
708{
709	struct tpm_buf buf;
710	int rc;
711
712	dev_info(&chip->dev, "starting up the TPM manually\n");
713
714	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_STARTUP);
715	if (rc < 0)
716		return rc;
717
718	tpm_buf_append_u16(&buf, TPM2_SU_CLEAR);
719	rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to start the TPM");
720	tpm_buf_destroy(&buf);
721
722	return rc;
723}
724
725/**
726 * tpm2_auto_startup - Perform the standard automatic TPM initialization
727 *                     sequence
728 * @chip: TPM chip to use
729 *
730 * Returns 0 on success, < 0 in case of fatal error.
731 */
732int tpm2_auto_startup(struct tpm_chip *chip)
733{
734	int rc;
735
736	rc = tpm2_get_timeouts(chip);
737	if (rc)
738		goto out;
739
740	rc = tpm2_do_selftest(chip);
741	if (rc && rc != TPM2_RC_INITIALIZE)
742		goto out;
743
744	if (rc == TPM2_RC_INITIALIZE) {
745		rc = tpm2_startup(chip);
746		if (rc)
747			goto out;
748
749		rc = tpm2_do_selftest(chip);
750		if (rc)
751			goto out;
752	}
753
754	rc = tpm2_get_cc_attrs_tbl(chip);
755	if (rc == TPM2_RC_FAILURE || (rc < 0 && rc != -ENOMEM)) {
756		dev_info(&chip->dev,
757			 "TPM in field failure mode, requires firmware upgrade\n");
758		chip->flags |= TPM_CHIP_FLAG_FIRMWARE_UPGRADE;
759		rc = 0;
760	}
 
 
 
 
 
761
762out:
763	/*
764	 * Infineon TPM in field upgrade mode will return no data for the number
765	 * of supported commands.
766	 */
767	if (rc == TPM2_RC_UPGRADE || rc == -ENODATA) {
768		dev_info(&chip->dev, "TPM in field upgrade mode, requires firmware upgrade\n");
769		chip->flags |= TPM_CHIP_FLAG_FIRMWARE_UPGRADE;
770		rc = 0;
771	}
772
773	if (rc > 0)
774		rc = -ENODEV;
775	return rc;
776}
777
778int tpm2_find_cc(struct tpm_chip *chip, u32 cc)
779{
780	u32 cc_mask;
781	int i;
782
783	cc_mask = 1 << TPM2_CC_ATTR_VENDOR | GENMASK(15, 0);
784	for (i = 0; i < chip->nr_commands; i++)
785		if (cc == (chip->cc_attrs_tbl[i] & cc_mask))
786			return i;
787
788	return -1;
789}
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) 2014, 2015 Intel Corporation
  4 *
  5 * Authors:
  6 * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
  7 *
  8 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
  9 *
 10 * This file contains TPM2 protocol implementations of the commands
 11 * used by the kernel internally.
 12 */
 13
 14#include "tpm.h"
 15#include <crypto/hash_info.h>
 16
 17static bool disable_pcr_integrity;
 18module_param(disable_pcr_integrity, bool, 0444);
 19MODULE_PARM_DESC(disable_pcr_integrity, "Disable integrity protection of TPM2_PCR_Extend");
 20
 21static struct tpm2_hash tpm2_hash_map[] = {
 22	{HASH_ALGO_SHA1, TPM_ALG_SHA1},
 23	{HASH_ALGO_SHA256, TPM_ALG_SHA256},
 24	{HASH_ALGO_SHA384, TPM_ALG_SHA384},
 25	{HASH_ALGO_SHA512, TPM_ALG_SHA512},
 26	{HASH_ALGO_SM3_256, TPM_ALG_SM3_256},
 27};
 28
 29int tpm2_get_timeouts(struct tpm_chip *chip)
 30{
 31	/* Fixed timeouts for TPM2 */
 32	chip->timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
 33	chip->timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
 34	chip->timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
 35	chip->timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
 36
 37	/* PTP spec timeouts */
 38	chip->duration[TPM_SHORT] = msecs_to_jiffies(TPM2_DURATION_SHORT);
 39	chip->duration[TPM_MEDIUM] = msecs_to_jiffies(TPM2_DURATION_MEDIUM);
 40	chip->duration[TPM_LONG] = msecs_to_jiffies(TPM2_DURATION_LONG);
 41
 42	/* Key creation commands long timeouts */
 43	chip->duration[TPM_LONG_LONG] =
 44		msecs_to_jiffies(TPM2_DURATION_LONG_LONG);
 45
 46	chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
 47
 48	return 0;
 49}
 50
 51/**
 52 * tpm2_ordinal_duration_index() - returns an index to the chip duration table
 53 * @ordinal: TPM command ordinal.
 54 *
 55 * The function returns an index to the chip duration table
 56 * (enum tpm_duration), that describes the maximum amount of
 57 * time the chip could take to return the result for a  particular ordinal.
 58 *
 59 * The values of the MEDIUM, and LONG durations are taken
 60 * from the PC Client Profile (PTP) specification (750, 2000 msec)
 61 *
 62 * LONG_LONG is for commands that generates keys which empirically takes
 63 * a longer time on some systems.
 64 *
 65 * Return:
 66 * * TPM_MEDIUM
 67 * * TPM_LONG
 68 * * TPM_LONG_LONG
 69 * * TPM_UNDEFINED
 70 */
 71static u8 tpm2_ordinal_duration_index(u32 ordinal)
 72{
 73	switch (ordinal) {
 74	/* Startup */
 75	case TPM2_CC_STARTUP:                 /* 144 */
 76		return TPM_MEDIUM;
 77
 78	case TPM2_CC_SELF_TEST:               /* 143 */
 79		return TPM_LONG;
 80
 81	case TPM2_CC_GET_RANDOM:              /* 17B */
 82		return TPM_LONG;
 83
 84	case TPM2_CC_SEQUENCE_UPDATE:         /* 15C */
 85		return TPM_MEDIUM;
 86	case TPM2_CC_SEQUENCE_COMPLETE:       /* 13E */
 87		return TPM_MEDIUM;
 88	case TPM2_CC_EVENT_SEQUENCE_COMPLETE: /* 185 */
 89		return TPM_MEDIUM;
 90	case TPM2_CC_HASH_SEQUENCE_START:     /* 186 */
 91		return TPM_MEDIUM;
 92
 93	case TPM2_CC_VERIFY_SIGNATURE:        /* 177 */
 94		return TPM_LONG_LONG;
 95
 96	case TPM2_CC_PCR_EXTEND:              /* 182 */
 97		return TPM_MEDIUM;
 98
 99	case TPM2_CC_HIERARCHY_CONTROL:       /* 121 */
100		return TPM_LONG;
101	case TPM2_CC_HIERARCHY_CHANGE_AUTH:   /* 129 */
102		return TPM_LONG;
103
104	case TPM2_CC_GET_CAPABILITY:          /* 17A */
105		return TPM_MEDIUM;
106
107	case TPM2_CC_NV_READ:                 /* 14E */
108		return TPM_LONG;
109
110	case TPM2_CC_CREATE_PRIMARY:          /* 131 */
111		return TPM_LONG_LONG;
112	case TPM2_CC_CREATE:                  /* 153 */
113		return TPM_LONG_LONG;
114	case TPM2_CC_CREATE_LOADED:           /* 191 */
115		return TPM_LONG_LONG;
116
117	default:
118		return TPM_UNDEFINED;
119	}
120}
121
122/**
123 * tpm2_calc_ordinal_duration() - calculate the maximum command duration
124 * @chip:    TPM chip to use.
125 * @ordinal: TPM command ordinal.
126 *
127 * The function returns the maximum amount of time the chip could take
128 * to return the result for a particular ordinal in jiffies.
129 *
130 * Return: A maximal duration time for an ordinal in jiffies.
131 */
132unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
133{
134	unsigned int index;
135
136	index = tpm2_ordinal_duration_index(ordinal);
137
138	if (index != TPM_UNDEFINED)
139		return chip->duration[index];
140	else
141		return msecs_to_jiffies(TPM2_DURATION_DEFAULT);
142}
143
144
145struct tpm2_pcr_read_out {
146	__be32	update_cnt;
147	__be32	pcr_selects_cnt;
148	__be16	hash_alg;
149	u8	pcr_select_size;
150	u8	pcr_select[TPM2_PCR_SELECT_MIN];
151	__be32	digests_cnt;
152	__be16	digest_size;
153	u8	digest[];
154} __packed;
155
156/**
157 * tpm2_pcr_read() - read a PCR value
158 * @chip:	TPM chip to use.
159 * @pcr_idx:	index of the PCR to read.
160 * @digest:	PCR bank and buffer current PCR value is written to.
161 * @digest_size_ptr:	pointer to variable that stores the digest size.
162 *
163 * Return: Same as with tpm_transmit_cmd.
164 */
165int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
166		  struct tpm_digest *digest, u16 *digest_size_ptr)
167{
168	int i;
169	int rc;
170	struct tpm_buf buf;
171	struct tpm2_pcr_read_out *out;
172	u8 pcr_select[TPM2_PCR_SELECT_MIN] = {0};
173	u16 digest_size;
174	u16 expected_digest_size = 0;
175
176	if (pcr_idx >= TPM2_PLATFORM_PCR)
177		return -EINVAL;
178
179	if (!digest_size_ptr) {
180		for (i = 0; i < chip->nr_allocated_banks &&
181		     chip->allocated_banks[i].alg_id != digest->alg_id; i++)
182			;
183
184		if (i == chip->nr_allocated_banks)
185			return -EINVAL;
186
187		expected_digest_size = chip->allocated_banks[i].digest_size;
188	}
189
190	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ);
191	if (rc)
192		return rc;
193
194	pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
195
196	tpm_buf_append_u32(&buf, 1);
197	tpm_buf_append_u16(&buf, digest->alg_id);
198	tpm_buf_append_u8(&buf, TPM2_PCR_SELECT_MIN);
199	tpm_buf_append(&buf, (const unsigned char *)pcr_select,
200		       sizeof(pcr_select));
201
202	rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to read a pcr value");
203	if (rc)
204		goto out;
205
206	out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE];
207	digest_size = be16_to_cpu(out->digest_size);
208	if (digest_size > sizeof(digest->digest) ||
209	    (!digest_size_ptr && digest_size != expected_digest_size)) {
210		rc = -EINVAL;
211		goto out;
212	}
213
214	if (digest_size_ptr)
215		*digest_size_ptr = digest_size;
216
217	memcpy(digest->digest, out->digest, digest_size);
218out:
219	tpm_buf_destroy(&buf);
220	return rc;
221}
222
 
 
 
 
 
 
 
223/**
224 * tpm2_pcr_extend() - extend a PCR value
225 *
226 * @chip:	TPM chip to use.
227 * @pcr_idx:	index of the PCR.
228 * @digests:	list of pcr banks and corresponding digest values to extend.
229 *
230 * Return: Same as with tpm_transmit_cmd.
231 */
232int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
233		    struct tpm_digest *digests)
234{
235	struct tpm_buf buf;
 
236	int rc;
237	int i;
238
239	if (!disable_pcr_integrity) {
240		rc = tpm2_start_auth_session(chip);
241		if (rc)
242			return rc;
243	}
244
245	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
246	if (rc) {
247		if (!disable_pcr_integrity)
248			tpm2_end_auth_session(chip);
249		return rc;
250	}
251
252	if (!disable_pcr_integrity) {
253		tpm_buf_append_name(chip, &buf, pcr_idx, NULL);
254		tpm_buf_append_hmac_session(chip, &buf, 0, NULL, 0);
255	} else {
256		tpm_buf_append_handle(chip, &buf, pcr_idx);
257		tpm_buf_append_auth(chip, &buf, 0, NULL, 0);
258	}
259
 
 
 
 
 
 
 
 
260	tpm_buf_append_u32(&buf, chip->nr_allocated_banks);
261
262	for (i = 0; i < chip->nr_allocated_banks; i++) {
263		tpm_buf_append_u16(&buf, digests[i].alg_id);
264		tpm_buf_append(&buf, (const unsigned char *)&digests[i].digest,
265			       chip->allocated_banks[i].digest_size);
266	}
267
268	if (!disable_pcr_integrity)
269		tpm_buf_fill_hmac_session(chip, &buf);
270	rc = tpm_transmit_cmd(chip, &buf, 0, "attempting extend a PCR value");
271	if (!disable_pcr_integrity)
272		rc = tpm_buf_check_hmac_response(chip, &buf, rc);
273
274	tpm_buf_destroy(&buf);
275
276	return rc;
277}
278
279struct tpm2_get_random_out {
280	__be16 size;
281	u8 buffer[TPM_MAX_RNG_DATA];
282} __packed;
283
284/**
285 * tpm2_get_random() - get random bytes from the TPM RNG
286 *
287 * @chip:	a &tpm_chip instance
288 * @dest:	destination buffer
289 * @max:	the max number of random bytes to pull
290 *
291 * Return:
292 *   size of the buffer on success,
293 *   -errno otherwise (positive TPM return codes are masked to -EIO)
294 */
295int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
296{
297	struct tpm2_get_random_out *out;
298	struct tpm_header *head;
299	struct tpm_buf buf;
300	u32 recd;
301	u32 num_bytes = max;
302	int err;
303	int total = 0;
304	int retries = 5;
305	u8 *dest_ptr = dest;
306	off_t offset;
307
308	if (!num_bytes || max > TPM_MAX_RNG_DATA)
309		return -EINVAL;
310
311	err = tpm2_start_auth_session(chip);
312	if (err)
313		return err;
314
315	err = tpm_buf_init(&buf, 0, 0);
316	if (err) {
317		tpm2_end_auth_session(chip);
318		return err;
319	}
320
321	do {
322		tpm_buf_reset(&buf, TPM2_ST_SESSIONS, TPM2_CC_GET_RANDOM);
323		tpm_buf_append_hmac_session_opt(chip, &buf, TPM2_SA_ENCRYPT
324						| TPM2_SA_CONTINUE_SESSION,
325						NULL, 0);
326		tpm_buf_append_u16(&buf, num_bytes);
327		tpm_buf_fill_hmac_session(chip, &buf);
328		err = tpm_transmit_cmd(chip, &buf,
329				       offsetof(struct tpm2_get_random_out,
330						buffer),
331				       "attempting get random");
332		err = tpm_buf_check_hmac_response(chip, &buf, err);
333		if (err) {
334			if (err > 0)
335				err = -EIO;
336			goto out;
337		}
338
339		head = (struct tpm_header *)buf.data;
340		offset = TPM_HEADER_SIZE;
341		/* Skip the parameter size field: */
342		if (be16_to_cpu(head->tag) == TPM2_ST_SESSIONS)
343			offset += 4;
344
345		out = (struct tpm2_get_random_out *)&buf.data[offset];
346		recd = min_t(u32, be16_to_cpu(out->size), num_bytes);
347		if (tpm_buf_length(&buf) <
348		    TPM_HEADER_SIZE +
349		    offsetof(struct tpm2_get_random_out, buffer) +
350		    recd) {
351			err = -EFAULT;
352			goto out;
353		}
354		memcpy(dest_ptr, out->buffer, recd);
355
356		dest_ptr += recd;
357		total += recd;
358		num_bytes -= recd;
359	} while (retries-- && total < max);
360
361	tpm_buf_destroy(&buf);
362	tpm2_end_auth_session(chip);
363
364	return total ? total : -EIO;
365out:
366	tpm_buf_destroy(&buf);
367	tpm2_end_auth_session(chip);
368	return err;
369}
370
371/**
372 * tpm2_flush_context() - execute a TPM2_FlushContext command
373 * @chip:	TPM chip to use
374 * @handle:	context handle
375 */
376void tpm2_flush_context(struct tpm_chip *chip, u32 handle)
377{
378	struct tpm_buf buf;
379	int rc;
380
381	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
382	if (rc) {
383		dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n",
384			 handle);
385		return;
386	}
387
388	tpm_buf_append_u32(&buf, handle);
389
390	tpm_transmit_cmd(chip, &buf, 0, "flushing context");
391	tpm_buf_destroy(&buf);
392}
393EXPORT_SYMBOL_GPL(tpm2_flush_context);
394
395struct tpm2_get_cap_out {
396	u8 more_data;
397	__be32 subcap_id;
398	__be32 property_cnt;
399	__be32 property_id;
400	__be32 value;
401} __packed;
402
403/**
404 * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
405 * @chip:		a &tpm_chip instance
406 * @property_id:	property ID.
407 * @value:		output variable.
408 * @desc:		passed to tpm_transmit_cmd()
409 *
410 * Return:
411 *   0 on success,
412 *   -errno or a TPM return code otherwise
413 */
414ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
415			const char *desc)
416{
417	struct tpm2_get_cap_out *out;
418	struct tpm_buf buf;
419	int rc;
420
421	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
422	if (rc)
423		return rc;
424	tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
425	tpm_buf_append_u32(&buf, property_id);
426	tpm_buf_append_u32(&buf, 1);
427	rc = tpm_transmit_cmd(chip, &buf, 0, NULL);
428	if (!rc) {
429		out = (struct tpm2_get_cap_out *)
430			&buf.data[TPM_HEADER_SIZE];
431		/*
432		 * To prevent failing boot up of some systems, Infineon TPM2.0
433		 * returns SUCCESS on TPM2_Startup in field upgrade mode. Also
434		 * the TPM2_Getcapability command returns a zero length list
435		 * in field upgrade mode.
436		 */
437		if (be32_to_cpu(out->property_cnt) > 0)
438			*value = be32_to_cpu(out->value);
439		else
440			rc = -ENODATA;
441	}
442	tpm_buf_destroy(&buf);
443	return rc;
444}
445EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
446
447/**
448 * tpm2_shutdown() - send a TPM shutdown command
449 *
450 * Sends a TPM shutdown command. The shutdown command is used in call
451 * sites where the system is going down. If it fails, there is not much
452 * that can be done except print an error message.
453 *
454 * @chip:		a &tpm_chip instance
455 * @shutdown_type:	TPM_SU_CLEAR or TPM_SU_STATE.
456 */
457void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
458{
459	struct tpm_buf buf;
460	int rc;
461
462	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SHUTDOWN);
463	if (rc)
464		return;
465	tpm_buf_append_u16(&buf, shutdown_type);
466	tpm_transmit_cmd(chip, &buf, 0, "stopping the TPM");
467	tpm_buf_destroy(&buf);
468}
469
470/**
471 * tpm2_do_selftest() - ensure that all self tests have passed
472 *
473 * @chip: TPM chip to use
474 *
475 * Return: Same as with tpm_transmit_cmd.
476 *
477 * The TPM can either run all self tests synchronously and then return
478 * RC_SUCCESS once all tests were successful. Or it can choose to run the tests
479 * asynchronously and return RC_TESTING immediately while the self tests still
480 * execute in the background. This function handles both cases and waits until
481 * all tests have completed.
482 */
483static int tpm2_do_selftest(struct tpm_chip *chip)
484{
485	struct tpm_buf buf;
486	int full;
487	int rc;
488
489	for (full = 0; full < 2; full++) {
490		rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SELF_TEST);
491		if (rc)
492			return rc;
493
494		tpm_buf_append_u8(&buf, full);
495		rc = tpm_transmit_cmd(chip, &buf, 0,
496				      "attempting the self test");
497		tpm_buf_destroy(&buf);
498
499		if (rc == TPM2_RC_TESTING)
500			rc = TPM2_RC_SUCCESS;
501		if (rc == TPM2_RC_INITIALIZE || rc == TPM2_RC_SUCCESS)
502			return rc;
503	}
504
505	return rc;
506}
507
508/**
509 * tpm2_probe() - probe for the TPM 2.0 protocol
510 * @chip:	a &tpm_chip instance
511 *
512 * Send an idempotent TPM 2.0 command and see whether there is TPM2 chip in the
513 * other end based on the response tag. The flag TPM_CHIP_FLAG_TPM2 is set by
514 * this function if this is the case.
515 *
516 * Return:
517 *   0 on success,
518 *   -errno otherwise
519 */
520int tpm2_probe(struct tpm_chip *chip)
521{
522	struct tpm_header *out;
523	struct tpm_buf buf;
524	int rc;
525
526	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
527	if (rc)
528		return rc;
529	tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
530	tpm_buf_append_u32(&buf, TPM_PT_TOTAL_COMMANDS);
531	tpm_buf_append_u32(&buf, 1);
532	rc = tpm_transmit_cmd(chip, &buf, 0, NULL);
533	/* We ignore TPM return codes on purpose. */
534	if (rc >=  0) {
535		out = (struct tpm_header *)buf.data;
536		if (be16_to_cpu(out->tag) == TPM2_ST_NO_SESSIONS)
537			chip->flags |= TPM_CHIP_FLAG_TPM2;
538	}
539	tpm_buf_destroy(&buf);
540	return 0;
541}
542EXPORT_SYMBOL_GPL(tpm2_probe);
543
544static int tpm2_init_bank_info(struct tpm_chip *chip, u32 bank_index)
545{
546	struct tpm_bank_info *bank = chip->allocated_banks + bank_index;
547	struct tpm_digest digest = { .alg_id = bank->alg_id };
548	int i;
549
550	/*
551	 * Avoid unnecessary PCR read operations to reduce overhead
552	 * and obtain identifiers of the crypto subsystem.
553	 */
554	for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {
555		enum hash_algo crypto_algo = tpm2_hash_map[i].crypto_id;
556
557		if (bank->alg_id != tpm2_hash_map[i].tpm_id)
558			continue;
559
560		bank->digest_size = hash_digest_size[crypto_algo];
561		bank->crypto_id = crypto_algo;
562		return 0;
563	}
564
565	bank->crypto_id = HASH_ALGO__LAST;
566
567	return tpm2_pcr_read(chip, 0, &digest, &bank->digest_size);
568}
569
570struct tpm2_pcr_selection {
571	__be16  hash_alg;
572	u8  size_of_select;
573	u8  pcr_select[3];
574} __packed;
575
576ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
577{
578	struct tpm2_pcr_selection pcr_selection;
579	struct tpm_buf buf;
580	void *marker;
581	void *end;
582	void *pcr_select_offset;
583	u32 sizeof_pcr_selection;
584	u32 nr_possible_banks;
585	u32 nr_alloc_banks = 0;
586	u16 hash_alg;
587	u32 rsp_len;
588	int rc;
589	int i = 0;
590
591	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
592	if (rc)
593		return rc;
594
595	tpm_buf_append_u32(&buf, TPM2_CAP_PCRS);
596	tpm_buf_append_u32(&buf, 0);
597	tpm_buf_append_u32(&buf, 1);
598
599	rc = tpm_transmit_cmd(chip, &buf, 9, "get tpm pcr allocation");
600	if (rc)
601		goto out;
602
603	nr_possible_banks = be32_to_cpup(
604		(__be32 *)&buf.data[TPM_HEADER_SIZE + 5]);
605
606	chip->allocated_banks = kcalloc(nr_possible_banks,
607					sizeof(*chip->allocated_banks),
608					GFP_KERNEL);
609	if (!chip->allocated_banks) {
610		rc = -ENOMEM;
611		goto out;
612	}
613
614	marker = &buf.data[TPM_HEADER_SIZE + 9];
615
616	rsp_len = be32_to_cpup((__be32 *)&buf.data[2]);
617	end = &buf.data[rsp_len];
618
619	for (i = 0; i < nr_possible_banks; i++) {
620		pcr_select_offset = marker +
621			offsetof(struct tpm2_pcr_selection, size_of_select);
622		if (pcr_select_offset >= end) {
623			rc = -EFAULT;
624			break;
625		}
626
627		memcpy(&pcr_selection, marker, sizeof(pcr_selection));
628		hash_alg = be16_to_cpu(pcr_selection.hash_alg);
629
630		pcr_select_offset = memchr_inv(pcr_selection.pcr_select, 0,
631					       pcr_selection.size_of_select);
632		if (pcr_select_offset) {
633			chip->allocated_banks[nr_alloc_banks].alg_id = hash_alg;
634
635			rc = tpm2_init_bank_info(chip, nr_alloc_banks);
636			if (rc < 0)
637				break;
638
639			nr_alloc_banks++;
640		}
641
642		sizeof_pcr_selection = sizeof(pcr_selection.hash_alg) +
643			sizeof(pcr_selection.size_of_select) +
644			pcr_selection.size_of_select;
645		marker = marker + sizeof_pcr_selection;
646	}
647
648	chip->nr_allocated_banks = nr_alloc_banks;
649out:
650	tpm_buf_destroy(&buf);
651
652	return rc;
653}
654
655int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
656{
657	struct tpm_buf buf;
658	u32 nr_commands;
659	__be32 *attrs;
660	u32 cc;
661	int i;
662	int rc;
663
664	rc = tpm2_get_tpm_pt(chip, TPM_PT_TOTAL_COMMANDS, &nr_commands, NULL);
665	if (rc)
666		goto out;
667
668	if (nr_commands > 0xFFFFF) {
669		rc = -EFAULT;
670		goto out;
671	}
672
673	chip->cc_attrs_tbl = devm_kcalloc(&chip->dev, 4, nr_commands,
674					  GFP_KERNEL);
675	if (!chip->cc_attrs_tbl) {
676		rc = -ENOMEM;
677		goto out;
678	}
679
680	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
681	if (rc)
682		goto out;
683
684	tpm_buf_append_u32(&buf, TPM2_CAP_COMMANDS);
685	tpm_buf_append_u32(&buf, TPM2_CC_FIRST);
686	tpm_buf_append_u32(&buf, nr_commands);
687
688	rc = tpm_transmit_cmd(chip, &buf, 9 + 4 * nr_commands, NULL);
689	if (rc) {
690		tpm_buf_destroy(&buf);
691		goto out;
692	}
693
694	if (nr_commands !=
695	    be32_to_cpup((__be32 *)&buf.data[TPM_HEADER_SIZE + 5])) {
696		rc = -EFAULT;
697		tpm_buf_destroy(&buf);
698		goto out;
699	}
700
701	chip->nr_commands = nr_commands;
702
703	attrs = (__be32 *)&buf.data[TPM_HEADER_SIZE + 9];
704	for (i = 0; i < nr_commands; i++, attrs++) {
705		chip->cc_attrs_tbl[i] = be32_to_cpup(attrs);
706		cc = chip->cc_attrs_tbl[i] & 0xFFFF;
707
708		if (cc == TPM2_CC_CONTEXT_SAVE || cc == TPM2_CC_FLUSH_CONTEXT) {
709			chip->cc_attrs_tbl[i] &=
710				~(GENMASK(2, 0) << TPM2_CC_ATTR_CHANDLES);
711			chip->cc_attrs_tbl[i] |= 1 << TPM2_CC_ATTR_CHANDLES;
712		}
713	}
714
715	tpm_buf_destroy(&buf);
716
717out:
718	if (rc > 0)
719		rc = -ENODEV;
720	return rc;
721}
722EXPORT_SYMBOL_GPL(tpm2_get_cc_attrs_tbl);
723
724/**
725 * tpm2_startup - turn on the TPM
726 * @chip: TPM chip to use
727 *
728 * Normally the firmware should start the TPM. This function is provided as a
729 * workaround if this does not happen. A legal case for this could be for
730 * example when a TPM emulator is used.
731 *
732 * Return: same as tpm_transmit_cmd()
733 */
734
735static int tpm2_startup(struct tpm_chip *chip)
736{
737	struct tpm_buf buf;
738	int rc;
739
740	dev_info(&chip->dev, "starting up the TPM manually\n");
741
742	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_STARTUP);
743	if (rc < 0)
744		return rc;
745
746	tpm_buf_append_u16(&buf, TPM2_SU_CLEAR);
747	rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to start the TPM");
748	tpm_buf_destroy(&buf);
749
750	return rc;
751}
752
753/**
754 * tpm2_auto_startup - Perform the standard automatic TPM initialization
755 *                     sequence
756 * @chip: TPM chip to use
757 *
758 * Returns 0 on success, < 0 in case of fatal error.
759 */
760int tpm2_auto_startup(struct tpm_chip *chip)
761{
762	int rc;
763
764	rc = tpm2_get_timeouts(chip);
765	if (rc)
766		goto out;
767
768	rc = tpm2_do_selftest(chip);
769	if (rc && rc != TPM2_RC_INITIALIZE)
770		goto out;
771
772	if (rc == TPM2_RC_INITIALIZE) {
773		rc = tpm2_startup(chip);
774		if (rc)
775			goto out;
776
777		rc = tpm2_do_selftest(chip);
778		if (rc)
779			goto out;
780	}
781
782	rc = tpm2_get_cc_attrs_tbl(chip);
783	if (rc == TPM2_RC_FAILURE || (rc < 0 && rc != -ENOMEM)) {
784		dev_info(&chip->dev,
785			 "TPM in field failure mode, requires firmware upgrade\n");
786		chip->flags |= TPM_CHIP_FLAG_FIRMWARE_UPGRADE;
787		rc = 0;
788	}
789
790	if (rc)
791		goto out;
792
793	rc = tpm2_sessions_init(chip);
794
795out:
796	/*
797	 * Infineon TPM in field upgrade mode will return no data for the number
798	 * of supported commands.
799	 */
800	if (rc == TPM2_RC_UPGRADE || rc == -ENODATA) {
801		dev_info(&chip->dev, "TPM in field upgrade mode, requires firmware upgrade\n");
802		chip->flags |= TPM_CHIP_FLAG_FIRMWARE_UPGRADE;
803		rc = 0;
804	}
805
806	if (rc > 0)
807		rc = -ENODEV;
808	return rc;
809}
810
811int tpm2_find_cc(struct tpm_chip *chip, u32 cc)
812{
813	u32 cc_mask;
814	int i;
815
816	cc_mask = 1 << TPM2_CC_ATTR_VENDOR | GENMASK(15, 0);
817	for (i = 0; i < chip->nr_commands; i++)
818		if (cc == (chip->cc_attrs_tbl[i] & cc_mask))
819			return i;
820
821	return -1;
822}