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  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) 2004 IBM Corporation
  4 * Authors:
  5 * Leendert van Doorn <leendert@watson.ibm.com>
  6 * Dave Safford <safford@watson.ibm.com>
  7 * Reiner Sailer <sailer@watson.ibm.com>
  8 * Kylene Hall <kjhall@us.ibm.com>
  9 *
 10 * Copyright (C) 2013 Obsidian Research Corp
 11 * Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
 12 *
 13 * sysfs filesystem inspection interface to the TPM
 14 */
 15#include <linux/device.h>
 16#include "tpm.h"
 17
 18struct tpm_readpubek_out {
 19	u8 algorithm[4];
 20	u8 encscheme[2];
 21	u8 sigscheme[2];
 22	__be32 paramsize;
 23	u8 parameters[12];
 24	__be32 keysize;
 25	u8 modulus[256];
 26	u8 checksum[20];
 27} __packed;
 28
 29#define READ_PUBEK_RESULT_MIN_BODY_SIZE (28 + 256)
 30#define TPM_ORD_READPUBEK 124
 31
 32static ssize_t pubek_show(struct device *dev, struct device_attribute *attr,
 33			  char *buf)
 34{
 35	struct tpm_buf tpm_buf;
 36	struct tpm_readpubek_out *out;
 37	int i;
 38	char *str = buf;
 39	struct tpm_chip *chip = to_tpm_chip(dev);
 40	char anti_replay[20];
 41
 42	memset(&anti_replay, 0, sizeof(anti_replay));
 43
 44	if (tpm_try_get_ops(chip))
 45		return 0;
 46
 47	if (tpm_buf_init(&tpm_buf, TPM_TAG_RQU_COMMAND, TPM_ORD_READPUBEK))
 48		goto out_ops;
 49
 50	tpm_buf_append(&tpm_buf, anti_replay, sizeof(anti_replay));
 51
 52	if (tpm_transmit_cmd(chip, &tpm_buf, READ_PUBEK_RESULT_MIN_BODY_SIZE,
 53			     "attempting to read the PUBEK"))
 54		goto out_buf;
 55
 56	out = (struct tpm_readpubek_out *)&tpm_buf.data[10];
 57	str +=
 58	    sprintf(str,
 59		    "Algorithm: %4ph\n"
 60		    "Encscheme: %2ph\n"
 61		    "Sigscheme: %2ph\n"
 62		    "Parameters: %12ph\n"
 63		    "Modulus length: %d\n"
 64		    "Modulus:\n",
 65		    out->algorithm,
 66		    out->encscheme,
 67		    out->sigscheme,
 68		    out->parameters,
 69		    be32_to_cpu(out->keysize));
 70
 71	for (i = 0; i < 256; i += 16)
 72		str += sprintf(str, "%16ph\n", &out->modulus[i]);
 73
 74out_buf:
 75	tpm_buf_destroy(&tpm_buf);
 76out_ops:
 77	tpm_put_ops(chip);
 78	return str - buf;
 79}
 80static DEVICE_ATTR_RO(pubek);
 81
 82static ssize_t pcrs_show(struct device *dev, struct device_attribute *attr,
 83			 char *buf)
 84{
 85	cap_t cap;
 86	u8 digest[TPM_DIGEST_SIZE];
 87	u32 i, j, num_pcrs;
 88	char *str = buf;
 89	struct tpm_chip *chip = to_tpm_chip(dev);
 90
 91	if (tpm_try_get_ops(chip))
 92		return 0;
 93
 94	if (tpm1_getcap(chip, TPM_CAP_PROP_PCR, &cap,
 95			"attempting to determine the number of PCRS",
 96			sizeof(cap.num_pcrs))) {
 97		tpm_put_ops(chip);
 98		return 0;
 99	}
100
101	num_pcrs = be32_to_cpu(cap.num_pcrs);
102	for (i = 0; i < num_pcrs; i++) {
103		if (tpm1_pcr_read(chip, i, digest)) {
104			str = buf;
105			break;
106		}
107		str += sprintf(str, "PCR-%02d: ", i);
108		for (j = 0; j < TPM_DIGEST_SIZE; j++)
109			str += sprintf(str, "%02X ", digest[j]);
110		str += sprintf(str, "\n");
111	}
112	tpm_put_ops(chip);
113	return str - buf;
114}
115static DEVICE_ATTR_RO(pcrs);
116
117static ssize_t enabled_show(struct device *dev, struct device_attribute *attr,
118		     char *buf)
119{
120	struct tpm_chip *chip = to_tpm_chip(dev);
121	ssize_t rc = 0;
122	cap_t cap;
123
124	if (tpm_try_get_ops(chip))
125		return 0;
126
127	if (tpm1_getcap(chip, TPM_CAP_FLAG_PERM, &cap,
128			"attempting to determine the permanent enabled state",
129			sizeof(cap.perm_flags)))
130		goto out_ops;
131
132	rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
133out_ops:
134	tpm_put_ops(chip);
135	return rc;
136}
137static DEVICE_ATTR_RO(enabled);
138
139static ssize_t active_show(struct device *dev, struct device_attribute *attr,
140		    char *buf)
141{
142	struct tpm_chip *chip = to_tpm_chip(dev);
143	ssize_t rc = 0;
144	cap_t cap;
145
146	if (tpm_try_get_ops(chip))
147		return 0;
148
149	if (tpm1_getcap(chip, TPM_CAP_FLAG_PERM, &cap,
150			"attempting to determine the permanent active state",
151			sizeof(cap.perm_flags)))
152		goto out_ops;
153
154	rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
155out_ops:
156	tpm_put_ops(chip);
157	return rc;
158}
159static DEVICE_ATTR_RO(active);
160
161static ssize_t owned_show(struct device *dev, struct device_attribute *attr,
162			  char *buf)
163{
164	struct tpm_chip *chip = to_tpm_chip(dev);
165	ssize_t rc = 0;
166	cap_t cap;
167
168	if (tpm_try_get_ops(chip))
169		return 0;
170
171	if (tpm1_getcap(to_tpm_chip(dev), TPM_CAP_PROP_OWNER, &cap,
172			"attempting to determine the owner state",
173			sizeof(cap.owned)))
174		goto out_ops;
175
176	rc = sprintf(buf, "%d\n", cap.owned);
177out_ops:
178	tpm_put_ops(chip);
179	return rc;
180}
181static DEVICE_ATTR_RO(owned);
182
183static ssize_t temp_deactivated_show(struct device *dev,
184				     struct device_attribute *attr, char *buf)
185{
186	struct tpm_chip *chip = to_tpm_chip(dev);
187	ssize_t rc = 0;
188	cap_t cap;
189
190	if (tpm_try_get_ops(chip))
191		return 0;
192
193	if (tpm1_getcap(to_tpm_chip(dev), TPM_CAP_FLAG_VOL, &cap,
194			"attempting to determine the temporary state",
195			sizeof(cap.stclear_flags)))
196		goto out_ops;
197
198	rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
199out_ops:
200	tpm_put_ops(chip);
201	return rc;
202}
203static DEVICE_ATTR_RO(temp_deactivated);
204
205static ssize_t caps_show(struct device *dev, struct device_attribute *attr,
206			 char *buf)
207{
208	struct tpm_chip *chip = to_tpm_chip(dev);
209	struct tpm1_version *version;
210	ssize_t rc = 0;
211	char *str = buf;
212	cap_t cap;
213
214	if (tpm_try_get_ops(chip))
215		return 0;
216
217	if (tpm1_getcap(chip, TPM_CAP_PROP_MANUFACTURER, &cap,
218			"attempting to determine the manufacturer",
219			sizeof(cap.manufacturer_id)))
220		goto out_ops;
221
222	str += sprintf(str, "Manufacturer: 0x%x\n",
223		       be32_to_cpu(cap.manufacturer_id));
224
225	/* TPM 1.2 */
226	if (!tpm1_getcap(chip, TPM_CAP_VERSION_1_2, &cap,
227			 "attempting to determine the 1.2 version",
228			 sizeof(cap.version2))) {
229		version = &cap.version2.version;
230		goto out_print;
231	}
232
233	/* TPM 1.1 */
234	if (tpm1_getcap(chip, TPM_CAP_VERSION_1_1, &cap,
235			"attempting to determine the 1.1 version",
236			sizeof(cap.version1))) {
237		goto out_ops;
238	}
239
240	version = &cap.version1;
241
242out_print:
243	str += sprintf(str,
244		       "TCG version: %d.%d\nFirmware version: %d.%d\n",
245		       version->major, version->minor,
246		       version->rev_major, version->rev_minor);
247
248	rc = str - buf;
249
250out_ops:
251	tpm_put_ops(chip);
252	return rc;
253}
254static DEVICE_ATTR_RO(caps);
255
256static ssize_t cancel_store(struct device *dev, struct device_attribute *attr,
257			    const char *buf, size_t count)
258{
259	struct tpm_chip *chip = to_tpm_chip(dev);
260
261	if (tpm_try_get_ops(chip))
262		return 0;
263
264	chip->ops->cancel(chip);
265	tpm_put_ops(chip);
266	return count;
267}
268static DEVICE_ATTR_WO(cancel);
269
270static ssize_t durations_show(struct device *dev, struct device_attribute *attr,
271			      char *buf)
272{
273	struct tpm_chip *chip = to_tpm_chip(dev);
274
275	if (chip->duration[TPM_LONG] == 0)
276		return 0;
277
278	return sprintf(buf, "%d %d %d [%s]\n",
279		       jiffies_to_usecs(chip->duration[TPM_SHORT]),
280		       jiffies_to_usecs(chip->duration[TPM_MEDIUM]),
281		       jiffies_to_usecs(chip->duration[TPM_LONG]),
282		       chip->duration_adjusted
283		       ? "adjusted" : "original");
284}
285static DEVICE_ATTR_RO(durations);
286
287static ssize_t timeouts_show(struct device *dev, struct device_attribute *attr,
288			     char *buf)
289{
290	struct tpm_chip *chip = to_tpm_chip(dev);
291
292	return sprintf(buf, "%d %d %d %d [%s]\n",
293		       jiffies_to_usecs(chip->timeout_a),
294		       jiffies_to_usecs(chip->timeout_b),
295		       jiffies_to_usecs(chip->timeout_c),
296		       jiffies_to_usecs(chip->timeout_d),
297		       chip->timeout_adjusted
298		       ? "adjusted" : "original");
299}
300static DEVICE_ATTR_RO(timeouts);
301
302static ssize_t tpm_version_major_show(struct device *dev,
303				  struct device_attribute *attr, char *buf)
304{
305	struct tpm_chip *chip = to_tpm_chip(dev);
306
307	return sprintf(buf, "%s\n", chip->flags & TPM_CHIP_FLAG_TPM2
308		       ? "2" : "1");
309}
310static DEVICE_ATTR_RO(tpm_version_major);
311
312static struct attribute *tpm1_dev_attrs[] = {
313	&dev_attr_pubek.attr,
314	&dev_attr_pcrs.attr,
315	&dev_attr_enabled.attr,
316	&dev_attr_active.attr,
317	&dev_attr_owned.attr,
318	&dev_attr_temp_deactivated.attr,
319	&dev_attr_caps.attr,
320	&dev_attr_cancel.attr,
321	&dev_attr_durations.attr,
322	&dev_attr_timeouts.attr,
323	&dev_attr_tpm_version_major.attr,
324	NULL,
325};
326
327static struct attribute *tpm2_dev_attrs[] = {
328	&dev_attr_tpm_version_major.attr,
329	NULL
330};
331
332static const struct attribute_group tpm1_dev_group = {
333	.attrs = tpm1_dev_attrs,
334};
335
336static const struct attribute_group tpm2_dev_group = {
337	.attrs = tpm2_dev_attrs,
338};
339
340struct tpm_pcr_attr {
341	int alg_id;
342	int pcr;
343	struct device_attribute attr;
344};
345
346#define to_tpm_pcr_attr(a) container_of(a, struct tpm_pcr_attr, attr)
347
348static ssize_t pcr_value_show(struct device *dev,
349			      struct device_attribute *attr,
350			      char *buf)
351{
352	struct tpm_pcr_attr *ha = to_tpm_pcr_attr(attr);
353	struct tpm_chip *chip = to_tpm_chip(dev);
354	struct tpm_digest digest;
355	int i;
356	int digest_size = 0;
357	int rc;
358	char *str = buf;
359
360	for (i = 0; i < chip->nr_allocated_banks; i++)
361		if (ha->alg_id == chip->allocated_banks[i].alg_id)
362			digest_size = chip->allocated_banks[i].digest_size;
363	/* should never happen */
364	if (!digest_size)
365		return -EINVAL;
366
367	digest.alg_id = ha->alg_id;
368	rc = tpm_pcr_read(chip, ha->pcr, &digest);
369	if (rc)
370		return rc;
371	for (i = 0; i < digest_size; i++)
372		str += sprintf(str, "%02X", digest.digest[i]);
373	str += sprintf(str, "\n");
374
375	return str - buf;
376}
377
378/*
379 * The following set of defines represents all the magic to build
380 * the per hash attribute groups for displaying each bank of PCRs.
381 * The only slight problem with this approach is that every PCR is
382 * hard coded to be present, so you don't know if an PCR is missing
383 * until a cat of the file returns -EINVAL
384 *
385 * Also note you must ignore checkpatch warnings in this macro
386 * code. This is deep macro magic that checkpatch.pl doesn't
387 * understand.
388 */
389
390/* Note, this must match TPM2_PLATFORM_PCR which is fixed at 24. */
391#define _TPM_HELPER(_alg, _hash, F) \
392	F(_alg, _hash, 0)	    \
393	F(_alg, _hash, 1)	    \
394	F(_alg, _hash, 2)	    \
395	F(_alg, _hash, 3)	    \
396	F(_alg, _hash, 4)	    \
397	F(_alg, _hash, 5)	    \
398	F(_alg, _hash, 6)	    \
399	F(_alg, _hash, 7)	    \
400	F(_alg, _hash, 8)	    \
401	F(_alg, _hash, 9)	    \
402	F(_alg, _hash, 10)	    \
403	F(_alg, _hash, 11)	    \
404	F(_alg, _hash, 12)	    \
405	F(_alg, _hash, 13)	    \
406	F(_alg, _hash, 14)	    \
407	F(_alg, _hash, 15)	    \
408	F(_alg, _hash, 16)	    \
409	F(_alg, _hash, 17)	    \
410	F(_alg, _hash, 18)	    \
411	F(_alg, _hash, 19)	    \
412	F(_alg, _hash, 20)	    \
413	F(_alg, _hash, 21)	    \
414	F(_alg, _hash, 22)	    \
415	F(_alg, _hash, 23)
416
417/* ignore checkpatch warning about trailing ; in macro. */
418#define PCR_ATTR(_alg, _hash, _pcr)				   \
419	static struct tpm_pcr_attr dev_attr_pcr_##_hash##_##_pcr = {	\
420		.alg_id = _alg,					   \
421		.pcr = _pcr,					   \
422		.attr = {					   \
423			.attr = {				   \
424				.name = __stringify(_pcr),	   \
425				.mode = 0444			   \
426			},					   \
427			.show = pcr_value_show			   \
428		}						   \
429	};
430
431#define PCR_ATTRS(_alg, _hash)			\
432	_TPM_HELPER(_alg, _hash, PCR_ATTR)
433
434/* ignore checkpatch warning about trailing , in macro. */
435#define PCR_ATTR_VAL(_alg, _hash, _pcr)		\
436	&dev_attr_pcr_##_hash##_##_pcr.attr.attr,
437
438#define PCR_ATTR_GROUP_ARRAY(_alg, _hash)		       \
439	static struct attribute *pcr_group_attrs_##_hash[] = { \
440		_TPM_HELPER(_alg, _hash, PCR_ATTR_VAL)	       \
441		NULL					       \
442	}
443
444#define PCR_ATTR_GROUP(_alg, _hash)			    \
445	static struct attribute_group pcr_group_##_hash = { \
446		.name = "pcr-" __stringify(_hash),	    \
447		.attrs = pcr_group_attrs_##_hash	    \
448	}
449
450#define PCR_ATTR_BUILD(_alg, _hash)	   \
451	PCR_ATTRS(_alg, _hash)		   \
452	PCR_ATTR_GROUP_ARRAY(_alg, _hash); \
453	PCR_ATTR_GROUP(_alg, _hash)
454/*
455 * End of macro structure to build an attribute group containing 24
456 * PCR value files for each supported hash algorithm
457 */
458
459/*
460 * The next set of macros implements the cleverness for each hash to
461 * build a static attribute group called pcr_group_<hash> which can be
462 * added to chip->groups[].
463 *
464 * The first argument is the TPM algorithm id and the second is the
465 * hash used as both the suffix and the group name.  Note: the group
466 * name is a directory in the top level tpm class with the name
467 * pcr-<hash>, so it must not clash with any other names already
468 * in the sysfs directory.
469 */
470PCR_ATTR_BUILD(TPM_ALG_SHA1, sha1);
471PCR_ATTR_BUILD(TPM_ALG_SHA256, sha256);
472PCR_ATTR_BUILD(TPM_ALG_SHA384, sha384);
473PCR_ATTR_BUILD(TPM_ALG_SHA512, sha512);
474PCR_ATTR_BUILD(TPM_ALG_SM3_256, sm3);
475
476
477void tpm_sysfs_add_device(struct tpm_chip *chip)
478{
479	int i;
480
481	WARN_ON(chip->groups_cnt != 0);
482
483	if (tpm_is_firmware_upgrade(chip))
484		return;
485
486	if (chip->flags & TPM_CHIP_FLAG_TPM2)
487		chip->groups[chip->groups_cnt++] = &tpm2_dev_group;
488	else
489		chip->groups[chip->groups_cnt++] = &tpm1_dev_group;
490
491	/* add one group for each bank hash */
492	for (i = 0; i < chip->nr_allocated_banks; i++) {
493		switch (chip->allocated_banks[i].alg_id) {
494		case TPM_ALG_SHA1:
495			chip->groups[chip->groups_cnt++] = &pcr_group_sha1;
496			break;
497		case TPM_ALG_SHA256:
498			chip->groups[chip->groups_cnt++] = &pcr_group_sha256;
499			break;
500		case TPM_ALG_SHA384:
501			chip->groups[chip->groups_cnt++] = &pcr_group_sha384;
502			break;
503		case TPM_ALG_SHA512:
504			chip->groups[chip->groups_cnt++] = &pcr_group_sha512;
505			break;
506		case TPM_ALG_SM3_256:
507			chip->groups[chip->groups_cnt++] = &pcr_group_sm3;
508			break;
509		default:
510			/*
511			 * If triggers, send a patch to add both a
512			 * PCR_ATTR_BUILD() macro above for the
513			 * missing algorithm as well as an additional
514			 * case in this switch statement.
515			 */
516			dev_err(&chip->dev,
517				"TPM with unsupported bank algorithm 0x%04x",
518				chip->allocated_banks[i].alg_id);
519			break;
520		}
521	}
522
523	/*
524	 * This will only trigger if someone has added an additional
525	 * hash to the tpm_algorithms enum without incrementing
526	 * TPM_MAX_HASHES.
527	 */
528	WARN_ON(chip->groups_cnt > TPM_MAX_HASHES + 1);
529}