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keys, trusted: select hash algorithm for TPM2 chips
[deliverable/linux.git] / drivers / char / tpm / tpm2-cmd.c
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_ATTR_USER_WITH_AUTH = BIT(6),
24 };
25
26 struct tpm2_startup_in {
27 __be16 startup_type;
28 } __packed;
29
30 struct tpm2_self_test_in {
31 u8 full_test;
32 } __packed;
33
34 struct tpm2_pcr_read_in {
35 __be32 pcr_selects_cnt;
36 __be16 hash_alg;
37 u8 pcr_select_size;
38 u8 pcr_select[TPM2_PCR_SELECT_MIN];
39 } __packed;
40
41 struct tpm2_pcr_read_out {
42 __be32 update_cnt;
43 __be32 pcr_selects_cnt;
44 __be16 hash_alg;
45 u8 pcr_select_size;
46 u8 pcr_select[TPM2_PCR_SELECT_MIN];
47 __be32 digests_cnt;
48 __be16 digest_size;
49 u8 digest[TPM_DIGEST_SIZE];
50 } __packed;
51
52 struct tpm2_null_auth_area {
53 __be32 handle;
54 __be16 nonce_size;
55 u8 attributes;
56 __be16 auth_size;
57 } __packed;
58
59 struct tpm2_pcr_extend_in {
60 __be32 pcr_idx;
61 __be32 auth_area_size;
62 struct tpm2_null_auth_area auth_area;
63 __be32 digest_cnt;
64 __be16 hash_alg;
65 u8 digest[TPM_DIGEST_SIZE];
66 } __packed;
67
68 struct tpm2_get_tpm_pt_in {
69 __be32 cap_id;
70 __be32 property_id;
71 __be32 property_cnt;
72 } __packed;
73
74 struct tpm2_get_tpm_pt_out {
75 u8 more_data;
76 __be32 subcap_id;
77 __be32 property_cnt;
78 __be32 property_id;
79 __be32 value;
80 } __packed;
81
82 struct tpm2_get_random_in {
83 __be16 size;
84 } __packed;
85
86 struct tpm2_get_random_out {
87 __be16 size;
88 u8 buffer[TPM_MAX_RNG_DATA];
89 } __packed;
90
91 union tpm2_cmd_params {
92 struct tpm2_startup_in startup_in;
93 struct tpm2_self_test_in selftest_in;
94 struct tpm2_pcr_read_in pcrread_in;
95 struct tpm2_pcr_read_out pcrread_out;
96 struct tpm2_pcr_extend_in pcrextend_in;
97 struct tpm2_get_tpm_pt_in get_tpm_pt_in;
98 struct tpm2_get_tpm_pt_out get_tpm_pt_out;
99 struct tpm2_get_random_in getrandom_in;
100 struct tpm2_get_random_out getrandom_out;
101 };
102
103 struct tpm2_cmd {
104 tpm_cmd_header header;
105 union tpm2_cmd_params params;
106 } __packed;
107
108 struct tpm2_hash {
109 unsigned int crypto_id;
110 unsigned int tpm_id;
111 };
112
113 static struct tpm2_hash tpm2_hash_map[] = {
114 {HASH_ALGO_SHA1, TPM2_ALG_SHA1},
115 {HASH_ALGO_SHA256, TPM2_ALG_SHA256},
116 {HASH_ALGO_SHA384, TPM2_ALG_SHA384},
117 {HASH_ALGO_SHA512, TPM2_ALG_SHA512},
118 {HASH_ALGO_SM3_256, TPM2_ALG_SM3_256},
119 };
120
121 /*
122 * Array with one entry per ordinal defining the maximum amount
123 * of time the chip could take to return the result. The values
124 * of the SHORT, MEDIUM, and LONG durations are taken from the
125 * PC Client Profile (PTP) specification.
126 */
127 static const u8 tpm2_ordinal_duration[TPM2_CC_LAST - TPM2_CC_FIRST + 1] = {
128 TPM_UNDEFINED, /* 11F */
129 TPM_UNDEFINED, /* 120 */
130 TPM_LONG, /* 121 */
131 TPM_UNDEFINED, /* 122 */
132 TPM_UNDEFINED, /* 123 */
133 TPM_UNDEFINED, /* 124 */
134 TPM_UNDEFINED, /* 125 */
135 TPM_UNDEFINED, /* 126 */
136 TPM_UNDEFINED, /* 127 */
137 TPM_UNDEFINED, /* 128 */
138 TPM_LONG, /* 129 */
139 TPM_UNDEFINED, /* 12a */
140 TPM_UNDEFINED, /* 12b */
141 TPM_UNDEFINED, /* 12c */
142 TPM_UNDEFINED, /* 12d */
143 TPM_UNDEFINED, /* 12e */
144 TPM_UNDEFINED, /* 12f */
145 TPM_UNDEFINED, /* 130 */
146 TPM_UNDEFINED, /* 131 */
147 TPM_UNDEFINED, /* 132 */
148 TPM_UNDEFINED, /* 133 */
149 TPM_UNDEFINED, /* 134 */
150 TPM_UNDEFINED, /* 135 */
151 TPM_UNDEFINED, /* 136 */
152 TPM_UNDEFINED, /* 137 */
153 TPM_UNDEFINED, /* 138 */
154 TPM_UNDEFINED, /* 139 */
155 TPM_UNDEFINED, /* 13a */
156 TPM_UNDEFINED, /* 13b */
157 TPM_UNDEFINED, /* 13c */
158 TPM_UNDEFINED, /* 13d */
159 TPM_MEDIUM, /* 13e */
160 TPM_UNDEFINED, /* 13f */
161 TPM_UNDEFINED, /* 140 */
162 TPM_UNDEFINED, /* 141 */
163 TPM_UNDEFINED, /* 142 */
164 TPM_LONG, /* 143 */
165 TPM_MEDIUM, /* 144 */
166 TPM_UNDEFINED, /* 145 */
167 TPM_UNDEFINED, /* 146 */
168 TPM_UNDEFINED, /* 147 */
169 TPM_UNDEFINED, /* 148 */
170 TPM_UNDEFINED, /* 149 */
171 TPM_UNDEFINED, /* 14a */
172 TPM_UNDEFINED, /* 14b */
173 TPM_UNDEFINED, /* 14c */
174 TPM_UNDEFINED, /* 14d */
175 TPM_LONG, /* 14e */
176 TPM_UNDEFINED, /* 14f */
177 TPM_UNDEFINED, /* 150 */
178 TPM_UNDEFINED, /* 151 */
179 TPM_UNDEFINED, /* 152 */
180 TPM_UNDEFINED, /* 153 */
181 TPM_UNDEFINED, /* 154 */
182 TPM_UNDEFINED, /* 155 */
183 TPM_UNDEFINED, /* 156 */
184 TPM_UNDEFINED, /* 157 */
185 TPM_UNDEFINED, /* 158 */
186 TPM_UNDEFINED, /* 159 */
187 TPM_UNDEFINED, /* 15a */
188 TPM_UNDEFINED, /* 15b */
189 TPM_MEDIUM, /* 15c */
190 TPM_UNDEFINED, /* 15d */
191 TPM_UNDEFINED, /* 15e */
192 TPM_UNDEFINED, /* 15f */
193 TPM_UNDEFINED, /* 160 */
194 TPM_UNDEFINED, /* 161 */
195 TPM_UNDEFINED, /* 162 */
196 TPM_UNDEFINED, /* 163 */
197 TPM_UNDEFINED, /* 164 */
198 TPM_UNDEFINED, /* 165 */
199 TPM_UNDEFINED, /* 166 */
200 TPM_UNDEFINED, /* 167 */
201 TPM_UNDEFINED, /* 168 */
202 TPM_UNDEFINED, /* 169 */
203 TPM_UNDEFINED, /* 16a */
204 TPM_UNDEFINED, /* 16b */
205 TPM_UNDEFINED, /* 16c */
206 TPM_UNDEFINED, /* 16d */
207 TPM_UNDEFINED, /* 16e */
208 TPM_UNDEFINED, /* 16f */
209 TPM_UNDEFINED, /* 170 */
210 TPM_UNDEFINED, /* 171 */
211 TPM_UNDEFINED, /* 172 */
212 TPM_UNDEFINED, /* 173 */
213 TPM_UNDEFINED, /* 174 */
214 TPM_UNDEFINED, /* 175 */
215 TPM_UNDEFINED, /* 176 */
216 TPM_LONG, /* 177 */
217 TPM_UNDEFINED, /* 178 */
218 TPM_UNDEFINED, /* 179 */
219 TPM_MEDIUM, /* 17a */
220 TPM_LONG, /* 17b */
221 TPM_UNDEFINED, /* 17c */
222 TPM_UNDEFINED, /* 17d */
223 TPM_UNDEFINED, /* 17e */
224 TPM_UNDEFINED, /* 17f */
225 TPM_UNDEFINED, /* 180 */
226 TPM_UNDEFINED, /* 181 */
227 TPM_MEDIUM, /* 182 */
228 TPM_UNDEFINED, /* 183 */
229 TPM_UNDEFINED, /* 184 */
230 TPM_MEDIUM, /* 185 */
231 TPM_MEDIUM, /* 186 */
232 TPM_UNDEFINED, /* 187 */
233 TPM_UNDEFINED, /* 188 */
234 TPM_UNDEFINED, /* 189 */
235 TPM_UNDEFINED, /* 18a */
236 TPM_UNDEFINED, /* 18b */
237 TPM_UNDEFINED, /* 18c */
238 TPM_UNDEFINED, /* 18d */
239 TPM_UNDEFINED, /* 18e */
240 TPM_UNDEFINED /* 18f */
241 };
242
243 #define TPM2_PCR_READ_IN_SIZE \
244 (sizeof(struct tpm_input_header) + \
245 sizeof(struct tpm2_pcr_read_in))
246
247 static const struct tpm_input_header tpm2_pcrread_header = {
248 .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
249 .length = cpu_to_be32(TPM2_PCR_READ_IN_SIZE),
250 .ordinal = cpu_to_be32(TPM2_CC_PCR_READ)
251 };
252
253 /**
254 * tpm2_pcr_read() - read a PCR value
255 * @chip: TPM chip to use.
256 * @pcr_idx: index of the PCR to read.
257 * @ref_buf: buffer to store the resulting hash,
258 *
259 * 0 is returned when the operation is successful. If a negative number is
260 * returned it remarks a POSIX error code. If a positive number is returned
261 * it remarks a TPM error.
262 */
263 int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
264 {
265 int rc;
266 struct tpm2_cmd cmd;
267 u8 *buf;
268
269 if (pcr_idx >= TPM2_PLATFORM_PCR)
270 return -EINVAL;
271
272 cmd.header.in = tpm2_pcrread_header;
273 cmd.params.pcrread_in.pcr_selects_cnt = cpu_to_be32(1);
274 cmd.params.pcrread_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
275 cmd.params.pcrread_in.pcr_select_size = TPM2_PCR_SELECT_MIN;
276
277 memset(cmd.params.pcrread_in.pcr_select, 0,
278 sizeof(cmd.params.pcrread_in.pcr_select));
279 cmd.params.pcrread_in.pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
280
281 rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
282 "attempting to read a pcr value");
283 if (rc == 0) {
284 buf = cmd.params.pcrread_out.digest;
285 memcpy(res_buf, buf, TPM_DIGEST_SIZE);
286 }
287
288 return rc;
289 }
290
291 #define TPM2_GET_PCREXTEND_IN_SIZE \
292 (sizeof(struct tpm_input_header) + \
293 sizeof(struct tpm2_pcr_extend_in))
294
295 static const struct tpm_input_header tpm2_pcrextend_header = {
296 .tag = cpu_to_be16(TPM2_ST_SESSIONS),
297 .length = cpu_to_be32(TPM2_GET_PCREXTEND_IN_SIZE),
298 .ordinal = cpu_to_be32(TPM2_CC_PCR_EXTEND)
299 };
300
301 /**
302 * tpm2_pcr_extend() - extend a PCR value
303 * @chip: TPM chip to use.
304 * @pcr_idx: index of the PCR.
305 * @hash: hash value to use for the extend operation.
306 *
307 * 0 is returned when the operation is successful. If a negative number is
308 * returned it remarks a POSIX error code. If a positive number is returned
309 * it remarks a TPM error.
310 */
311 int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash)
312 {
313 struct tpm2_cmd cmd;
314 int rc;
315
316 cmd.header.in = tpm2_pcrextend_header;
317 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
318 cmd.params.pcrextend_in.auth_area_size =
319 cpu_to_be32(sizeof(struct tpm2_null_auth_area));
320 cmd.params.pcrextend_in.auth_area.handle =
321 cpu_to_be32(TPM2_RS_PW);
322 cmd.params.pcrextend_in.auth_area.nonce_size = 0;
323 cmd.params.pcrextend_in.auth_area.attributes = 0;
324 cmd.params.pcrextend_in.auth_area.auth_size = 0;
325 cmd.params.pcrextend_in.digest_cnt = cpu_to_be32(1);
326 cmd.params.pcrextend_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
327 memcpy(cmd.params.pcrextend_in.digest, hash, TPM_DIGEST_SIZE);
328
329 rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
330 "attempting extend a PCR value");
331
332 return rc;
333 }
334
335 #define TPM2_GETRANDOM_IN_SIZE \
336 (sizeof(struct tpm_input_header) + \
337 sizeof(struct tpm2_get_random_in))
338
339 static const struct tpm_input_header tpm2_getrandom_header = {
340 .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
341 .length = cpu_to_be32(TPM2_GETRANDOM_IN_SIZE),
342 .ordinal = cpu_to_be32(TPM2_CC_GET_RANDOM)
343 };
344
345 /**
346 * tpm2_get_random() - get random bytes from the TPM RNG
347 * @chip: TPM chip to use
348 * @out: destination buffer for the random bytes
349 * @max: the max number of bytes to write to @out
350 *
351 * 0 is returned when the operation is successful. If a negative number is
352 * returned it remarks a POSIX error code. If a positive number is returned
353 * it remarks a TPM error.
354 */
355 int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
356 {
357 struct tpm2_cmd cmd;
358 u32 recd;
359 u32 num_bytes;
360 int err;
361 int total = 0;
362 int retries = 5;
363 u8 *dest = out;
364
365 num_bytes = min_t(u32, max, sizeof(cmd.params.getrandom_out.buffer));
366
367 if (!out || !num_bytes ||
368 max > sizeof(cmd.params.getrandom_out.buffer))
369 return -EINVAL;
370
371 do {
372 cmd.header.in = tpm2_getrandom_header;
373 cmd.params.getrandom_in.size = cpu_to_be16(num_bytes);
374
375 err = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
376 "attempting get random");
377 if (err)
378 break;
379
380 recd = min_t(u32, be16_to_cpu(cmd.params.getrandom_out.size),
381 num_bytes);
382 memcpy(dest, cmd.params.getrandom_out.buffer, recd);
383
384 dest += recd;
385 total += recd;
386 num_bytes -= recd;
387 } while (retries-- && total < max);
388
389 return total ? total : -EIO;
390 }
391
392 #define TPM2_GET_TPM_PT_IN_SIZE \
393 (sizeof(struct tpm_input_header) + \
394 sizeof(struct tpm2_get_tpm_pt_in))
395
396 static const struct tpm_input_header tpm2_get_tpm_pt_header = {
397 .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
398 .length = cpu_to_be32(TPM2_GET_TPM_PT_IN_SIZE),
399 .ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
400 };
401
402 /**
403 * Append TPMS_AUTH_COMMAND to the buffer. The buffer must be allocated with
404 * tpm_buf_alloc().
405 *
406 * @param buf: an allocated tpm_buf instance
407 * @param nonce: the session nonce, may be NULL if not used
408 * @param nonce_len: the session nonce length, may be 0 if not used
409 * @param attributes: the session attributes
410 * @param hmac: the session HMAC or password, may be NULL if not used
411 * @param hmac_len: the session HMAC or password length, maybe 0 if not used
412 */
413 static void tpm2_buf_append_auth(struct tpm_buf *buf, u32 session_handle,
414 const u8 *nonce, u16 nonce_len,
415 u8 attributes,
416 const u8 *hmac, u16 hmac_len)
417 {
418 tpm_buf_append_u32(buf, 9 + nonce_len + hmac_len);
419 tpm_buf_append_u32(buf, session_handle);
420 tpm_buf_append_u16(buf, nonce_len);
421
422 if (nonce && nonce_len)
423 tpm_buf_append(buf, nonce, nonce_len);
424
425 tpm_buf_append_u8(buf, attributes);
426 tpm_buf_append_u16(buf, hmac_len);
427
428 if (hmac && hmac_len)
429 tpm_buf_append(buf, hmac, hmac_len);
430 }
431
432 /**
433 * tpm2_seal_trusted() - seal a trusted key
434 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
435 * @options: authentication values and other options
436 * @payload: the key data in clear and encrypted form
437 *
438 * Returns < 0 on error and 0 on success.
439 */
440 int tpm2_seal_trusted(struct tpm_chip *chip,
441 struct trusted_key_payload *payload,
442 struct trusted_key_options *options)
443 {
444 unsigned int blob_len;
445 struct tpm_buf buf;
446 u32 hash;
447 int i;
448 int rc;
449
450 for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {
451 if (options->hash == tpm2_hash_map[i].crypto_id) {
452 hash = tpm2_hash_map[i].tpm_id;
453 break;
454 }
455 }
456
457 if (i == ARRAY_SIZE(tpm2_hash_map))
458 return -EINVAL;
459
460 rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
461 if (rc)
462 return rc;
463
464 tpm_buf_append_u32(&buf, options->keyhandle);
465 tpm2_buf_append_auth(&buf, TPM2_RS_PW,
466 NULL /* nonce */, 0,
467 0 /* session_attributes */,
468 options->keyauth /* hmac */,
469 TPM_DIGEST_SIZE);
470
471 /* sensitive */
472 tpm_buf_append_u16(&buf, 4 + TPM_DIGEST_SIZE + payload->key_len + 1);
473
474 tpm_buf_append_u16(&buf, TPM_DIGEST_SIZE);
475 tpm_buf_append(&buf, options->blobauth, TPM_DIGEST_SIZE);
476 tpm_buf_append_u16(&buf, payload->key_len + 1);
477 tpm_buf_append(&buf, payload->key, payload->key_len);
478 tpm_buf_append_u8(&buf, payload->migratable);
479
480 /* public */
481 tpm_buf_append_u16(&buf, 14);
482
483 tpm_buf_append_u16(&buf, TPM2_ALG_KEYEDHASH);
484 tpm_buf_append_u16(&buf, hash);
485 tpm_buf_append_u32(&buf, TPM2_ATTR_USER_WITH_AUTH);
486 tpm_buf_append_u16(&buf, 0); /* policy digest size */
487 tpm_buf_append_u16(&buf, TPM2_ALG_NULL);
488 tpm_buf_append_u16(&buf, 0);
489
490 /* outside info */
491 tpm_buf_append_u16(&buf, 0);
492
493 /* creation PCR */
494 tpm_buf_append_u32(&buf, 0);
495
496 if (buf.flags & TPM_BUF_OVERFLOW) {
497 rc = -E2BIG;
498 goto out;
499 }
500
501 rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, "sealing data");
502 if (rc)
503 goto out;
504
505 blob_len = be32_to_cpup((__be32 *) &buf.data[TPM_HEADER_SIZE]);
506 if (blob_len > MAX_BLOB_SIZE) {
507 rc = -E2BIG;
508 goto out;
509 }
510
511 memcpy(payload->blob, &buf.data[TPM_HEADER_SIZE + 4], blob_len);
512 payload->blob_len = blob_len;
513
514 out:
515 tpm_buf_destroy(&buf);
516
517 if (rc > 0) {
518 if ((rc & TPM2_RC_HASH) == TPM2_RC_HASH)
519 rc = -EINVAL;
520 else
521 rc = -EPERM;
522 }
523
524 return rc;
525 }
526
527 static int tpm2_load(struct tpm_chip *chip,
528 struct trusted_key_payload *payload,
529 struct trusted_key_options *options,
530 u32 *blob_handle)
531 {
532 struct tpm_buf buf;
533 unsigned int private_len;
534 unsigned int public_len;
535 unsigned int blob_len;
536 int rc;
537
538 private_len = be16_to_cpup((__be16 *) &payload->blob[0]);
539 if (private_len > (payload->blob_len - 2))
540 return -E2BIG;
541
542 public_len = be16_to_cpup((__be16 *) &payload->blob[2 + private_len]);
543 blob_len = private_len + public_len + 4;
544 if (blob_len > payload->blob_len)
545 return -E2BIG;
546
547 rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
548 if (rc)
549 return rc;
550
551 tpm_buf_append_u32(&buf, options->keyhandle);
552 tpm2_buf_append_auth(&buf, TPM2_RS_PW,
553 NULL /* nonce */, 0,
554 0 /* session_attributes */,
555 options->keyauth /* hmac */,
556 TPM_DIGEST_SIZE);
557
558 tpm_buf_append(&buf, payload->blob, blob_len);
559
560 if (buf.flags & TPM_BUF_OVERFLOW) {
561 rc = -E2BIG;
562 goto out;
563 }
564
565 rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, "loading blob");
566 if (!rc)
567 *blob_handle = be32_to_cpup(
568 (__be32 *) &buf.data[TPM_HEADER_SIZE]);
569
570 out:
571 tpm_buf_destroy(&buf);
572
573 if (rc > 0)
574 rc = -EPERM;
575
576 return rc;
577 }
578
579 static void tpm2_flush_context(struct tpm_chip *chip, u32 handle)
580 {
581 struct tpm_buf buf;
582 int rc;
583
584 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
585 if (rc) {
586 dev_warn(chip->pdev, "0x%08x was not flushed, out of memory\n",
587 handle);
588 return;
589 }
590
591 tpm_buf_append_u32(&buf, handle);
592
593 rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, "flushing context");
594 if (rc)
595 dev_warn(chip->pdev, "0x%08x was not flushed, rc=%d\n", handle,
596 rc);
597
598 tpm_buf_destroy(&buf);
599 }
600
601 static int tpm2_unseal(struct tpm_chip *chip,
602 struct trusted_key_payload *payload,
603 struct trusted_key_options *options,
604 u32 blob_handle)
605 {
606 struct tpm_buf buf;
607 u16 data_len;
608 u8 *data;
609 int rc;
610
611 rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
612 if (rc)
613 return rc;
614
615 tpm_buf_append_u32(&buf, blob_handle);
616 tpm2_buf_append_auth(&buf, TPM2_RS_PW,
617 NULL /* nonce */, 0,
618 0 /* session_attributes */,
619 options->blobauth /* hmac */,
620 TPM_DIGEST_SIZE);
621
622 rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, "unsealing");
623 if (rc > 0)
624 rc = -EPERM;
625
626 if (!rc) {
627 data_len = be16_to_cpup(
628 (__be16 *) &buf.data[TPM_HEADER_SIZE + 4]);
629 data = &buf.data[TPM_HEADER_SIZE + 6];
630
631 memcpy(payload->key, data, data_len - 1);
632 payload->key_len = data_len - 1;
633 payload->migratable = data[data_len - 1];
634 }
635
636 tpm_buf_destroy(&buf);
637 return rc;
638 }
639
640 /**
641 * tpm_unseal_trusted() - unseal a trusted key
642 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
643 * @options: authentication values and other options
644 * @payload: the key data in clear and encrypted form
645 *
646 * Returns < 0 on error and 0 on success.
647 */
648 int tpm2_unseal_trusted(struct tpm_chip *chip,
649 struct trusted_key_payload *payload,
650 struct trusted_key_options *options)
651 {
652 u32 blob_handle;
653 int rc;
654
655 rc = tpm2_load(chip, payload, options, &blob_handle);
656 if (rc)
657 return rc;
658
659 rc = tpm2_unseal(chip, payload, options, blob_handle);
660
661 tpm2_flush_context(chip, blob_handle);
662
663 return rc;
664 }
665
666 /**
667 * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
668 * @chip: TPM chip to use.
669 * @property_id: property ID.
670 * @value: output variable.
671 * @desc: passed to tpm_transmit_cmd()
672 *
673 * 0 is returned when the operation is successful. If a negative number is
674 * returned it remarks a POSIX error code. If a positive number is returned
675 * it remarks a TPM error.
676 */
677 ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id, u32 *value,
678 const char *desc)
679 {
680 struct tpm2_cmd cmd;
681 int rc;
682
683 cmd.header.in = tpm2_get_tpm_pt_header;
684 cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
685 cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(property_id);
686 cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
687
688 rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), desc);
689 if (!rc)
690 *value = cmd.params.get_tpm_pt_out.value;
691
692 return rc;
693 }
694
695 #define TPM2_STARTUP_IN_SIZE \
696 (sizeof(struct tpm_input_header) + \
697 sizeof(struct tpm2_startup_in))
698
699 static const struct tpm_input_header tpm2_startup_header = {
700 .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
701 .length = cpu_to_be32(TPM2_STARTUP_IN_SIZE),
702 .ordinal = cpu_to_be32(TPM2_CC_STARTUP)
703 };
704
705 /**
706 * tpm2_startup() - send startup command to the TPM chip
707 * @chip: TPM chip to use.
708 * @startup_type startup type. The value is either
709 * TPM_SU_CLEAR or TPM_SU_STATE.
710 *
711 * 0 is returned when the operation is successful. If a negative number is
712 * returned it remarks a POSIX error code. If a positive number is returned
713 * it remarks a TPM error.
714 */
715 int tpm2_startup(struct tpm_chip *chip, u16 startup_type)
716 {
717 struct tpm2_cmd cmd;
718
719 cmd.header.in = tpm2_startup_header;
720
721 cmd.params.startup_in.startup_type = cpu_to_be16(startup_type);
722 return tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
723 "attempting to start the TPM");
724 }
725 EXPORT_SYMBOL_GPL(tpm2_startup);
726
727 #define TPM2_SHUTDOWN_IN_SIZE \
728 (sizeof(struct tpm_input_header) + \
729 sizeof(struct tpm2_startup_in))
730
731 static const struct tpm_input_header tpm2_shutdown_header = {
732 .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
733 .length = cpu_to_be32(TPM2_SHUTDOWN_IN_SIZE),
734 .ordinal = cpu_to_be32(TPM2_CC_SHUTDOWN)
735 };
736
737 /**
738 * tpm2_shutdown() - send shutdown command to the TPM chip
739 * @chip: TPM chip to use.
740 * @shutdown_type shutdown type. The value is either
741 * TPM_SU_CLEAR or TPM_SU_STATE.
742 */
743 void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
744 {
745 struct tpm2_cmd cmd;
746 int rc;
747
748 cmd.header.in = tpm2_shutdown_header;
749 cmd.params.startup_in.startup_type = cpu_to_be16(shutdown_type);
750
751 rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), "stopping the TPM");
752
753 /* In places where shutdown command is sent there's no much we can do
754 * except print the error code on a system failure.
755 */
756 if (rc < 0)
757 dev_warn(chip->pdev, "transmit returned %d while stopping the TPM",
758 rc);
759 }
760 EXPORT_SYMBOL_GPL(tpm2_shutdown);
761
762 /*
763 * tpm2_calc_ordinal_duration() - maximum duration for a command
764 * @chip: TPM chip to use.
765 * @ordinal: command code number.
766 *
767 * 0 is returned when the operation is successful. If a negative number is
768 * returned it remarks a POSIX error code. If a positive number is returned
769 * it remarks a TPM error.
770 */
771 unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
772 {
773 int index = TPM_UNDEFINED;
774 int duration = 0;
775
776 if (ordinal >= TPM2_CC_FIRST && ordinal <= TPM2_CC_LAST)
777 index = tpm2_ordinal_duration[ordinal - TPM2_CC_FIRST];
778
779 if (index != TPM_UNDEFINED)
780 duration = chip->vendor.duration[index];
781
782 if (duration <= 0)
783 duration = 2 * 60 * HZ;
784
785 return duration;
786 }
787 EXPORT_SYMBOL_GPL(tpm2_calc_ordinal_duration);
788
789 #define TPM2_SELF_TEST_IN_SIZE \
790 (sizeof(struct tpm_input_header) + \
791 sizeof(struct tpm2_self_test_in))
792
793 static const struct tpm_input_header tpm2_selftest_header = {
794 .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
795 .length = cpu_to_be32(TPM2_SELF_TEST_IN_SIZE),
796 .ordinal = cpu_to_be32(TPM2_CC_SELF_TEST)
797 };
798
799 /**
800 * tpm2_continue_selftest() - start a self test
801 * @chip: TPM chip to use
802 * @full: test all commands instead of testing only those that were not
803 * previously tested.
804 *
805 * 0 is returned when the operation is successful. If a negative number is
806 * returned it remarks a POSIX error code. If a positive number is returned
807 * it remarks a TPM error.
808 */
809 static int tpm2_start_selftest(struct tpm_chip *chip, bool full)
810 {
811 int rc;
812 struct tpm2_cmd cmd;
813
814 cmd.header.in = tpm2_selftest_header;
815 cmd.params.selftest_in.full_test = full;
816
817 rc = tpm_transmit_cmd(chip, &cmd, TPM2_SELF_TEST_IN_SIZE,
818 "continue selftest");
819
820 /* At least some prototype chips seem to give RC_TESTING error
821 * immediately. This is a workaround for that.
822 */
823 if (rc == TPM2_RC_TESTING) {
824 dev_warn(chip->pdev, "Got RC_TESTING, ignoring\n");
825 rc = 0;
826 }
827
828 return rc;
829 }
830
831 /**
832 * tpm2_do_selftest() - run a full self test
833 * @chip: TPM chip to use
834 *
835 * During the self test TPM2 commands return with the error code RC_TESTING.
836 * Waiting is done by issuing PCR read until it executes successfully.
837 *
838 * 0 is returned when the operation is successful. If a negative number is
839 * returned it remarks a POSIX error code. If a positive number is returned
840 * it remarks a TPM error.
841 */
842 int tpm2_do_selftest(struct tpm_chip *chip)
843 {
844 int rc;
845 unsigned int loops;
846 unsigned int delay_msec = 100;
847 unsigned long duration;
848 struct tpm2_cmd cmd;
849 int i;
850
851 duration = tpm2_calc_ordinal_duration(chip, TPM2_CC_SELF_TEST);
852
853 loops = jiffies_to_msecs(duration) / delay_msec;
854
855 rc = tpm2_start_selftest(chip, true);
856 if (rc)
857 return rc;
858
859 for (i = 0; i < loops; i++) {
860 /* Attempt to read a PCR value */
861 cmd.header.in = tpm2_pcrread_header;
862 cmd.params.pcrread_in.pcr_selects_cnt = cpu_to_be32(1);
863 cmd.params.pcrread_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
864 cmd.params.pcrread_in.pcr_select_size = TPM2_PCR_SELECT_MIN;
865 cmd.params.pcrread_in.pcr_select[0] = 0x01;
866 cmd.params.pcrread_in.pcr_select[1] = 0x00;
867 cmd.params.pcrread_in.pcr_select[2] = 0x00;
868
869 rc = tpm_transmit_cmd(chip, (u8 *) &cmd, sizeof(cmd), NULL);
870 if (rc < 0)
871 break;
872
873 rc = be32_to_cpu(cmd.header.out.return_code);
874 if (rc != TPM2_RC_TESTING)
875 break;
876
877 msleep(delay_msec);
878 }
879
880 return rc;
881 }
882 EXPORT_SYMBOL_GPL(tpm2_do_selftest);
883
884 /**
885 * tpm2_gen_interrupt() - generate an interrupt
886 * @chip: TPM chip to use
887 *
888 * 0 is returned when the operation is successful. If a negative number is
889 * returned it remarks a POSIX error code. If a positive number is returned
890 * it remarks a TPM error.
891 */
892 int tpm2_gen_interrupt(struct tpm_chip *chip)
893 {
894 u32 dummy;
895
896 return tpm2_get_tpm_pt(chip, 0x100, &dummy,
897 "attempting to generate an interrupt");
898 }
899 EXPORT_SYMBOL_GPL(tpm2_gen_interrupt);
900
901 /**
902 * tpm2_probe() - probe TPM 2.0
903 * @chip: TPM chip to use
904 *
905 * Send idempotent TPM 2.0 command and see whether TPM 2.0 chip replied based on
906 * the reply tag.
907 */
908 int tpm2_probe(struct tpm_chip *chip)
909 {
910 struct tpm2_cmd cmd;
911 int rc;
912
913 cmd.header.in = tpm2_get_tpm_pt_header;
914 cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
915 cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(0x100);
916 cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
917
918 rc = tpm_transmit(chip, (const char *) &cmd, sizeof(cmd));
919 if (rc < 0)
920 return rc;
921 else if (rc < TPM_HEADER_SIZE)
922 return -EFAULT;
923
924 if (be16_to_cpu(cmd.header.out.tag) == TPM2_ST_NO_SESSIONS)
925 chip->flags |= TPM_CHIP_FLAG_TPM2;
926
927 return 0;
928 }
929 EXPORT_SYMBOL_GPL(tpm2_probe);
Linux kernel - Deliverables
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