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_hash {
31 unsigned int crypto_id;
32 unsigned int tpm_id;
33 };
34
35 static struct tpm2_hash tpm2_hash_map[] = {
36 {HASH_ALGO_SHA1, TPM2_ALG_SHA1},
37 {HASH_ALGO_SHA256, TPM2_ALG_SHA256},
38 {HASH_ALGO_SHA384, TPM2_ALG_SHA384},
39 {HASH_ALGO_SHA512, TPM2_ALG_SHA512},
40 {HASH_ALGO_SM3_256, TPM2_ALG_SM3_256},
41 };
42
43 /*
44 * Array with one entry per ordinal defining the maximum amount
45 * of time the chip could take to return the result. The values
46 * of the SHORT, MEDIUM, and LONG durations are taken from the
47 * PC Client Profile (PTP) specification.
48 * LONG_LONG is for commands that generates keys which empirically
49 * takes longer time on some systems.
50 */
51 static const u8 tpm2_ordinal_duration[TPM2_CC_LAST - TPM2_CC_FIRST + 1] = {
52 TPM_UNDEFINED, /* 11F */
53 TPM_UNDEFINED, /* 120 */
54 TPM_LONG, /* 121 */
55 TPM_UNDEFINED, /* 122 */
56 TPM_UNDEFINED, /* 123 */
57 TPM_UNDEFINED, /* 124 */
58 TPM_UNDEFINED, /* 125 */
59 TPM_UNDEFINED, /* 126 */
60 TPM_UNDEFINED, /* 127 */
61 TPM_UNDEFINED, /* 128 */
62 TPM_LONG, /* 129 */
63 TPM_UNDEFINED, /* 12a */
64 TPM_UNDEFINED, /* 12b */
65 TPM_UNDEFINED, /* 12c */
66 TPM_UNDEFINED, /* 12d */
67 TPM_UNDEFINED, /* 12e */
68 TPM_UNDEFINED, /* 12f */
69 TPM_UNDEFINED, /* 130 */
70 TPM_LONG_LONG, /* 131 */
71 TPM_UNDEFINED, /* 132 */
72 TPM_UNDEFINED, /* 133 */
73 TPM_UNDEFINED, /* 134 */
74 TPM_UNDEFINED, /* 135 */
75 TPM_UNDEFINED, /* 136 */
76 TPM_UNDEFINED, /* 137 */
77 TPM_UNDEFINED, /* 138 */
78 TPM_UNDEFINED, /* 139 */
79 TPM_UNDEFINED, /* 13a */
80 TPM_UNDEFINED, /* 13b */
81 TPM_UNDEFINED, /* 13c */
82 TPM_UNDEFINED, /* 13d */
83 TPM_MEDIUM, /* 13e */
84 TPM_UNDEFINED, /* 13f */
85 TPM_UNDEFINED, /* 140 */
86 TPM_UNDEFINED, /* 141 */
87 TPM_UNDEFINED, /* 142 */
88 TPM_LONG, /* 143 */
89 TPM_MEDIUM, /* 144 */
90 TPM_UNDEFINED, /* 145 */
91 TPM_UNDEFINED, /* 146 */
92 TPM_UNDEFINED, /* 147 */
93 TPM_UNDEFINED, /* 148 */
94 TPM_UNDEFINED, /* 149 */
95 TPM_UNDEFINED, /* 14a */
96 TPM_UNDEFINED, /* 14b */
97 TPM_UNDEFINED, /* 14c */
98 TPM_UNDEFINED, /* 14d */
99 TPM_LONG, /* 14e */
100 TPM_UNDEFINED, /* 14f */
101 TPM_UNDEFINED, /* 150 */
102 TPM_UNDEFINED, /* 151 */
103 TPM_UNDEFINED, /* 152 */
104 TPM_LONG_LONG, /* 153 */
105 TPM_UNDEFINED, /* 154 */
106 TPM_UNDEFINED, /* 155 */
107 TPM_UNDEFINED, /* 156 */
108 TPM_UNDEFINED, /* 157 */
109 TPM_UNDEFINED, /* 158 */
110 TPM_UNDEFINED, /* 159 */
111 TPM_UNDEFINED, /* 15a */
112 TPM_UNDEFINED, /* 15b */
113 TPM_MEDIUM, /* 15c */
114 TPM_UNDEFINED, /* 15d */
115 TPM_UNDEFINED, /* 15e */
116 TPM_UNDEFINED, /* 15f */
117 TPM_UNDEFINED, /* 160 */
118 TPM_UNDEFINED, /* 161 */
119 TPM_UNDEFINED, /* 162 */
120 TPM_UNDEFINED, /* 163 */
121 TPM_UNDEFINED, /* 164 */
122 TPM_UNDEFINED, /* 165 */
123 TPM_UNDEFINED, /* 166 */
124 TPM_UNDEFINED, /* 167 */
125 TPM_UNDEFINED, /* 168 */
126 TPM_UNDEFINED, /* 169 */
127 TPM_UNDEFINED, /* 16a */
128 TPM_UNDEFINED, /* 16b */
129 TPM_UNDEFINED, /* 16c */
130 TPM_UNDEFINED, /* 16d */
131 TPM_UNDEFINED, /* 16e */
132 TPM_UNDEFINED, /* 16f */
133 TPM_UNDEFINED, /* 170 */
134 TPM_UNDEFINED, /* 171 */
135 TPM_UNDEFINED, /* 172 */
136 TPM_UNDEFINED, /* 173 */
137 TPM_UNDEFINED, /* 174 */
138 TPM_UNDEFINED, /* 175 */
139 TPM_UNDEFINED, /* 176 */
140 TPM_LONG, /* 177 */
141 TPM_UNDEFINED, /* 178 */
142 TPM_UNDEFINED, /* 179 */
143 TPM_MEDIUM, /* 17a */
144 TPM_LONG, /* 17b */
145 TPM_UNDEFINED, /* 17c */
146 TPM_UNDEFINED, /* 17d */
147 TPM_UNDEFINED, /* 17e */
148 TPM_UNDEFINED, /* 17f */
149 TPM_UNDEFINED, /* 180 */
150 TPM_UNDEFINED, /* 181 */
151 TPM_MEDIUM, /* 182 */
152 TPM_UNDEFINED, /* 183 */
153 TPM_UNDEFINED, /* 184 */
154 TPM_MEDIUM, /* 185 */
155 TPM_MEDIUM, /* 186 */
156 TPM_UNDEFINED, /* 187 */
157 TPM_UNDEFINED, /* 188 */
158 TPM_UNDEFINED, /* 189 */
159 TPM_UNDEFINED, /* 18a */
160 TPM_UNDEFINED, /* 18b */
161 TPM_UNDEFINED, /* 18c */
162 TPM_UNDEFINED, /* 18d */
163 TPM_UNDEFINED, /* 18e */
164 TPM_UNDEFINED /* 18f */
165 };
166
167 struct tpm2_pcr_read_out {
168 __be32 update_cnt;
169 __be32 pcr_selects_cnt;
170 __be16 hash_alg;
171 u8 pcr_select_size;
172 u8 pcr_select[TPM2_PCR_SELECT_MIN];
173 __be32 digests_cnt;
174 __be16 digest_size;
175 u8 digest[];
176 } __packed;
177
178 /**
179 * tpm2_pcr_read() - read a PCR value
180 * @chip: TPM chip to use.
181 * @pcr_idx: index of the PCR to read.
182 * @res_buf: buffer to store the resulting hash.
183 *
184 * Return: Same as with tpm_transmit_cmd.
185 */
tpm2_pcr_read(struct tpm_chip * chip,int pcr_idx,u8 * res_buf)186 int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
187 {
188 int rc;
189 struct tpm_buf buf;
190 struct tpm2_pcr_read_out *out;
191 u8 pcr_select[TPM2_PCR_SELECT_MIN] = {0};
192
193 if (pcr_idx >= TPM2_PLATFORM_PCR)
194 return -EINVAL;
195
196 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ);
197 if (rc)
198 return rc;
199
200 pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
201
202 tpm_buf_append_u32(&buf, 1);
203 tpm_buf_append_u16(&buf, TPM2_ALG_SHA1);
204 tpm_buf_append_u8(&buf, TPM2_PCR_SELECT_MIN);
205 tpm_buf_append(&buf, (const unsigned char *)pcr_select,
206 sizeof(pcr_select));
207
208 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
209 res_buf ? "attempting to read a pcr value" : NULL);
210 if (rc == 0 && res_buf) {
211 out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE];
212 memcpy(res_buf, out->digest, SHA1_DIGEST_SIZE);
213 }
214
215 tpm_buf_destroy(&buf);
216 return rc;
217 }
218
219 struct 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 * @count: number of digests passed.
232 * @digests: list of pcr banks and corresponding digest values to extend.
233 *
234 * Return: Same as with tpm_transmit_cmd.
235 */
tpm2_pcr_extend(struct tpm_chip * chip,int pcr_idx,u32 count,struct tpm2_digest * digests)236 int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, u32 count,
237 struct tpm2_digest *digests)
238 {
239 struct tpm_buf buf;
240 struct tpm2_null_auth_area auth_area;
241 int rc;
242 int i;
243 int j;
244
245 if (count > ARRAY_SIZE(chip->active_banks))
246 return -EINVAL;
247
248 rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
249 if (rc)
250 return rc;
251
252 tpm_buf_append_u32(&buf, pcr_idx);
253
254 auth_area.handle = cpu_to_be32(TPM2_RS_PW);
255 auth_area.nonce_size = 0;
256 auth_area.attributes = 0;
257 auth_area.auth_size = 0;
258
259 tpm_buf_append_u32(&buf, sizeof(struct tpm2_null_auth_area));
260 tpm_buf_append(&buf, (const unsigned char *)&auth_area,
261 sizeof(auth_area));
262 tpm_buf_append_u32(&buf, count);
263
264 for (i = 0; i < count; i++) {
265 for (j = 0; j < ARRAY_SIZE(tpm2_hash_map); j++) {
266 if (digests[i].alg_id != tpm2_hash_map[j].tpm_id)
267 continue;
268 tpm_buf_append_u16(&buf, digests[i].alg_id);
269 tpm_buf_append(&buf, (const unsigned char
270 *)&digests[i].digest,
271 hash_digest_size[tpm2_hash_map[j].crypto_id]);
272 }
273 }
274
275 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
276 "attempting extend a PCR value");
277
278 tpm_buf_destroy(&buf);
279
280 return rc;
281 }
282
283
284 struct tpm2_get_random_out {
285 __be16 size;
286 u8 buffer[TPM_MAX_RNG_DATA];
287 } __packed;
288
289 /**
290 * tpm2_get_random() - get random bytes from the TPM RNG
291 *
292 * @chip: a &tpm_chip instance
293 * @dest: destination buffer
294 * @max: the max number of random bytes to pull
295 *
296 * Return:
297 * size of the buffer on success,
298 * -errno otherwise
299 */
tpm2_get_random(struct tpm_chip * chip,u8 * dest,size_t max)300 int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
301 {
302 struct tpm2_get_random_out *out;
303 struct tpm_buf buf;
304 u32 recd;
305 u32 num_bytes = max;
306 int err;
307 int total = 0;
308 int retries = 5;
309 u8 *dest_ptr = dest;
310
311 if (!num_bytes || max > TPM_MAX_RNG_DATA)
312 return -EINVAL;
313
314 err = tpm_buf_init(&buf, 0, 0);
315 if (err)
316 return err;
317
318 do {
319 tpm_buf_reset(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_RANDOM);
320 tpm_buf_append_u16(&buf, num_bytes);
321 err = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE,
322 offsetof(struct tpm2_get_random_out,
323 buffer),
324 0, "attempting get random");
325 if (err)
326 goto out;
327
328 out = (struct tpm2_get_random_out *)
329 &buf.data[TPM_HEADER_SIZE];
330 recd = min_t(u32, be16_to_cpu(out->size), num_bytes);
331 if (tpm_buf_length(&buf) <
332 offsetof(struct tpm2_get_random_out, buffer) + recd) {
333 err = -EFAULT;
334 goto out;
335 }
336 memcpy(dest_ptr, out->buffer, recd);
337
338 dest_ptr += recd;
339 total += recd;
340 num_bytes -= recd;
341 } while (retries-- && total < max);
342
343 tpm_buf_destroy(&buf);
344 return total ? total : -EIO;
345 out:
346 tpm_buf_destroy(&buf);
347 return err;
348 }
349
350 /**
351 * tpm2_flush_context_cmd() - execute a TPM2_FlushContext command
352 * @chip: TPM chip to use
353 * @payload: the key data in clear and encrypted form
354 * @options: authentication values and other options
355 *
356 * Return: same as with tpm_transmit_cmd
357 */
tpm2_flush_context_cmd(struct tpm_chip * chip,u32 handle,unsigned int flags)358 void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
359 unsigned int flags)
360 {
361 struct tpm_buf buf;
362 int rc;
363
364 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
365 if (rc) {
366 dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n",
367 handle);
368 return;
369 }
370
371 tpm_buf_append_u32(&buf, handle);
372
373 (void) tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, flags,
374 "flushing context");
375
376 tpm_buf_destroy(&buf);
377 }
378
379 /**
380 * tpm_buf_append_auth() - append TPMS_AUTH_COMMAND to the buffer.
381 *
382 * @buf: an allocated tpm_buf instance
383 * @session_handle: session handle
384 * @nonce: the session nonce, may be NULL if not used
385 * @nonce_len: the session nonce length, may be 0 if not used
386 * @attributes: the session attributes
387 * @hmac: the session HMAC or password, may be NULL if not used
388 * @hmac_len: the session HMAC or password length, maybe 0 if not used
389 */
tpm2_buf_append_auth(struct tpm_buf * buf,u32 session_handle,const u8 * nonce,u16 nonce_len,u8 attributes,const u8 * hmac,u16 hmac_len)390 static void tpm2_buf_append_auth(struct tpm_buf *buf, u32 session_handle,
391 const u8 *nonce, u16 nonce_len,
392 u8 attributes,
393 const u8 *hmac, u16 hmac_len)
394 {
395 tpm_buf_append_u32(buf, 9 + nonce_len + hmac_len);
396 tpm_buf_append_u32(buf, session_handle);
397 tpm_buf_append_u16(buf, nonce_len);
398
399 if (nonce && nonce_len)
400 tpm_buf_append(buf, nonce, nonce_len);
401
402 tpm_buf_append_u8(buf, attributes);
403 tpm_buf_append_u16(buf, hmac_len);
404
405 if (hmac && hmac_len)
406 tpm_buf_append(buf, hmac, hmac_len);
407 }
408
409 /**
410 * tpm2_seal_trusted() - seal the payload of a trusted key
411 *
412 * @chip: TPM chip to use
413 * @payload: the key data in clear and encrypted form
414 * @options: authentication values and other options
415 *
416 * Return: < 0 on error and 0 on success.
417 */
tpm2_seal_trusted(struct tpm_chip * chip,struct trusted_key_payload * payload,struct trusted_key_options * options)418 int tpm2_seal_trusted(struct tpm_chip *chip,
419 struct trusted_key_payload *payload,
420 struct trusted_key_options *options)
421 {
422 unsigned int blob_len;
423 struct tpm_buf buf;
424 u32 hash;
425 int i;
426 int rc;
427
428 for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {
429 if (options->hash == tpm2_hash_map[i].crypto_id) {
430 hash = tpm2_hash_map[i].tpm_id;
431 break;
432 }
433 }
434
435 if (i == ARRAY_SIZE(tpm2_hash_map))
436 return -EINVAL;
437
438 rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
439 if (rc)
440 return rc;
441
442 tpm_buf_append_u32(&buf, options->keyhandle);
443 tpm2_buf_append_auth(&buf, TPM2_RS_PW,
444 NULL /* nonce */, 0,
445 0 /* session_attributes */,
446 options->keyauth /* hmac */,
447 TPM_DIGEST_SIZE);
448
449 /* sensitive */
450 tpm_buf_append_u16(&buf, 4 + TPM_DIGEST_SIZE + payload->key_len + 1);
451
452 tpm_buf_append_u16(&buf, TPM_DIGEST_SIZE);
453 tpm_buf_append(&buf, options->blobauth, TPM_DIGEST_SIZE);
454 tpm_buf_append_u16(&buf, payload->key_len + 1);
455 tpm_buf_append(&buf, payload->key, payload->key_len);
456 tpm_buf_append_u8(&buf, payload->migratable);
457
458 /* public */
459 tpm_buf_append_u16(&buf, 14 + options->policydigest_len);
460 tpm_buf_append_u16(&buf, TPM2_ALG_KEYEDHASH);
461 tpm_buf_append_u16(&buf, hash);
462
463 /* policy */
464 if (options->policydigest_len) {
465 tpm_buf_append_u32(&buf, 0);
466 tpm_buf_append_u16(&buf, options->policydigest_len);
467 tpm_buf_append(&buf, options->policydigest,
468 options->policydigest_len);
469 } else {
470 tpm_buf_append_u32(&buf, TPM2_OA_USER_WITH_AUTH);
471 tpm_buf_append_u16(&buf, 0);
472 }
473
474 /* public parameters */
475 tpm_buf_append_u16(&buf, TPM2_ALG_NULL);
476 tpm_buf_append_u16(&buf, 0);
477
478 /* outside info */
479 tpm_buf_append_u16(&buf, 0);
480
481 /* creation PCR */
482 tpm_buf_append_u32(&buf, 0);
483
484 if (buf.flags & TPM_BUF_OVERFLOW) {
485 rc = -E2BIG;
486 goto out;
487 }
488
489 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 4, 0,
490 "sealing data");
491 if (rc)
492 goto out;
493
494 blob_len = be32_to_cpup((__be32 *) &buf.data[TPM_HEADER_SIZE]);
495 if (blob_len > MAX_BLOB_SIZE) {
496 rc = -E2BIG;
497 goto out;
498 }
499 if (tpm_buf_length(&buf) < TPM_HEADER_SIZE + 4 + blob_len) {
500 rc = -EFAULT;
501 goto out;
502 }
503
504 memcpy(payload->blob, &buf.data[TPM_HEADER_SIZE + 4], blob_len);
505 payload->blob_len = blob_len;
506
507 out:
508 tpm_buf_destroy(&buf);
509
510 if (rc > 0) {
511 if (tpm2_rc_value(rc) == TPM2_RC_HASH)
512 rc = -EINVAL;
513 else
514 rc = -EPERM;
515 }
516
517 return rc;
518 }
519
520 /**
521 * tpm2_load_cmd() - execute a TPM2_Load command
522 *
523 * @chip: TPM chip to use
524 * @payload: the key data in clear and encrypted form
525 * @options: authentication values and other options
526 * @blob_handle: returned blob handle
527 * @flags: tpm transmit flags
528 *
529 * Return: 0 on success.
530 * -E2BIG on wrong payload size.
531 * -EPERM on tpm error status.
532 * < 0 error from tpm_transmit_cmd.
533 */
tpm2_load_cmd(struct tpm_chip * chip,struct trusted_key_payload * payload,struct trusted_key_options * options,u32 * blob_handle,unsigned int flags)534 static int tpm2_load_cmd(struct tpm_chip *chip,
535 struct trusted_key_payload *payload,
536 struct trusted_key_options *options,
537 u32 *blob_handle, unsigned int flags)
538 {
539 struct tpm_buf buf;
540 unsigned int private_len;
541 unsigned int public_len;
542 unsigned int blob_len;
543 int rc;
544
545 private_len = be16_to_cpup((__be16 *) &payload->blob[0]);
546 if (private_len > (payload->blob_len - 2))
547 return -E2BIG;
548
549 public_len = be16_to_cpup((__be16 *) &payload->blob[2 + private_len]);
550 blob_len = private_len + public_len + 4;
551 if (blob_len > payload->blob_len)
552 return -E2BIG;
553
554 rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
555 if (rc)
556 return rc;
557
558 tpm_buf_append_u32(&buf, options->keyhandle);
559 tpm2_buf_append_auth(&buf, TPM2_RS_PW,
560 NULL /* nonce */, 0,
561 0 /* session_attributes */,
562 options->keyauth /* hmac */,
563 TPM_DIGEST_SIZE);
564
565 tpm_buf_append(&buf, payload->blob, blob_len);
566
567 if (buf.flags & TPM_BUF_OVERFLOW) {
568 rc = -E2BIG;
569 goto out;
570 }
571
572 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 4, flags,
573 "loading blob");
574 if (!rc)
575 *blob_handle = be32_to_cpup(
576 (__be32 *) &buf.data[TPM_HEADER_SIZE]);
577
578 out:
579 tpm_buf_destroy(&buf);
580
581 if (rc > 0)
582 rc = -EPERM;
583
584 return rc;
585 }
586
587 /**
588 * tpm2_unseal_cmd() - execute a TPM2_Unload command
589 *
590 * @chip: TPM chip to use
591 * @payload: the key data in clear and encrypted form
592 * @options: authentication values and other options
593 * @blob_handle: blob handle
594 * @flags: tpm_transmit_cmd flags
595 *
596 * Return: 0 on success
597 * -EPERM on tpm error status
598 * < 0 error from tpm_transmit_cmd
599 */
tpm2_unseal_cmd(struct tpm_chip * chip,struct trusted_key_payload * payload,struct trusted_key_options * options,u32 blob_handle,unsigned int flags)600 static int tpm2_unseal_cmd(struct tpm_chip *chip,
601 struct trusted_key_payload *payload,
602 struct trusted_key_options *options,
603 u32 blob_handle, unsigned int flags)
604 {
605 struct tpm_buf buf;
606 u16 data_len;
607 u8 *data;
608 int rc;
609
610 rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
611 if (rc)
612 return rc;
613
614 tpm_buf_append_u32(&buf, blob_handle);
615 tpm2_buf_append_auth(&buf,
616 options->policyhandle ?
617 options->policyhandle : TPM2_RS_PW,
618 NULL /* nonce */, 0,
619 TPM2_SA_CONTINUE_SESSION,
620 options->blobauth /* hmac */,
621 TPM_DIGEST_SIZE);
622
623 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 6, flags,
624 "unsealing");
625 if (rc > 0)
626 rc = -EPERM;
627
628 if (!rc) {
629 data_len = be16_to_cpup(
630 (__be16 *) &buf.data[TPM_HEADER_SIZE + 4]);
631 if (data_len < MIN_KEY_SIZE || data_len > MAX_KEY_SIZE + 1) {
632 rc = -EFAULT;
633 goto out;
634 }
635
636 if (tpm_buf_length(&buf) < TPM_HEADER_SIZE + 6 + data_len) {
637 rc = -EFAULT;
638 goto out;
639 }
640 data = &buf.data[TPM_HEADER_SIZE + 6];
641
642 memcpy(payload->key, data, data_len - 1);
643 payload->key_len = data_len - 1;
644 payload->migratable = data[data_len - 1];
645 }
646
647 out:
648 tpm_buf_destroy(&buf);
649 return rc;
650 }
651
652 /**
653 * tpm2_unseal_trusted() - unseal the payload of a trusted key
654 *
655 * @chip: TPM chip to use
656 * @payload: the key data in clear and encrypted form
657 * @options: authentication values and other options
658 *
659 * Return: Same as with tpm_transmit_cmd.
660 */
tpm2_unseal_trusted(struct tpm_chip * chip,struct trusted_key_payload * payload,struct trusted_key_options * options)661 int tpm2_unseal_trusted(struct tpm_chip *chip,
662 struct trusted_key_payload *payload,
663 struct trusted_key_options *options)
664 {
665 u32 blob_handle;
666 int rc;
667
668 mutex_lock(&chip->tpm_mutex);
669 rc = tpm2_load_cmd(chip, payload, options, &blob_handle,
670 TPM_TRANSMIT_UNLOCKED);
671 if (rc)
672 goto out;
673
674 rc = tpm2_unseal_cmd(chip, payload, options, blob_handle,
675 TPM_TRANSMIT_UNLOCKED);
676 tpm2_flush_context_cmd(chip, blob_handle, TPM_TRANSMIT_UNLOCKED);
677 out:
678 mutex_unlock(&chip->tpm_mutex);
679 return rc;
680 }
681
682 struct tpm2_get_cap_out {
683 u8 more_data;
684 __be32 subcap_id;
685 __be32 property_cnt;
686 __be32 property_id;
687 __be32 value;
688 } __packed;
689
690 /**
691 * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
692 * @chip: a &tpm_chip instance
693 * @property_id: property ID.
694 * @value: output variable.
695 * @desc: passed to tpm_transmit_cmd()
696 *
697 * Return:
698 * 0 on success,
699 * -errno or a TPM return code otherwise
700 */
tpm2_get_tpm_pt(struct tpm_chip * chip,u32 property_id,u32 * value,const char * desc)701 ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id, u32 *value,
702 const char *desc)
703 {
704 struct tpm2_get_cap_out *out;
705 struct tpm_buf buf;
706 int rc;
707
708 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
709 if (rc)
710 return rc;
711 tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
712 tpm_buf_append_u32(&buf, property_id);
713 tpm_buf_append_u32(&buf, 1);
714 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, NULL);
715 if (!rc) {
716 out = (struct tpm2_get_cap_out *)
717 &buf.data[TPM_HEADER_SIZE];
718 *value = be32_to_cpu(out->value);
719 }
720 tpm_buf_destroy(&buf);
721 return rc;
722 }
723 EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
724
725 /**
726 * tpm2_shutdown() - send a TPM shutdown command
727 *
728 * Sends a TPM shutdown command. The shutdown command is used in call
729 * sites where the system is going down. If it fails, there is not much
730 * that can be done except print an error message.
731 *
732 * @chip: a &tpm_chip instance
733 * @shutdown_type: TPM_SU_CLEAR or TPM_SU_STATE.
734 */
tpm2_shutdown(struct tpm_chip * chip,u16 shutdown_type)735 void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
736 {
737 struct tpm_buf buf;
738 int rc;
739
740 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SHUTDOWN);
741 if (rc)
742 return;
743 tpm_buf_append_u16(&buf, shutdown_type);
744 tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
745 "stopping the TPM");
746 tpm_buf_destroy(&buf);
747 }
748
749 /*
750 * tpm2_calc_ordinal_duration() - maximum duration for a command
751 *
752 * @chip: TPM chip to use.
753 * @ordinal: command code number.
754 *
755 * Return: maximum duration for a command
756 */
tpm2_calc_ordinal_duration(struct tpm_chip * chip,u32 ordinal)757 unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
758 {
759 int index = TPM_UNDEFINED;
760 int duration = 0;
761
762 if (ordinal >= TPM2_CC_FIRST && ordinal <= TPM2_CC_LAST)
763 index = tpm2_ordinal_duration[ordinal - TPM2_CC_FIRST];
764
765 if (index != TPM_UNDEFINED)
766 duration = chip->duration[index];
767
768 if (duration <= 0)
769 duration = msecs_to_jiffies(TPM2_DURATION_DEFAULT);
770
771 return duration;
772 }
773 EXPORT_SYMBOL_GPL(tpm2_calc_ordinal_duration);
774
775 /**
776 * tpm2_do_selftest() - ensure that all self tests have passed
777 *
778 * @chip: TPM chip to use
779 *
780 * Return: Same as with tpm_transmit_cmd.
781 *
782 * The TPM can either run all self tests synchronously and then return
783 * RC_SUCCESS once all tests were successful. Or it can choose to run the tests
784 * asynchronously and return RC_TESTING immediately while the self tests still
785 * execute in the background. This function handles both cases and waits until
786 * all tests have completed.
787 */
tpm2_do_selftest(struct tpm_chip * chip)788 static int tpm2_do_selftest(struct tpm_chip *chip)
789 {
790 struct tpm_buf buf;
791 int full;
792 int rc;
793
794 for (full = 0; full < 2; full++) {
795 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SELF_TEST);
796 if (rc)
797 return rc;
798
799 tpm_buf_append_u8(&buf, full);
800 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
801 "attempting the self test");
802 tpm_buf_destroy(&buf);
803
804 if (rc == TPM2_RC_TESTING)
805 rc = TPM2_RC_SUCCESS;
806 if (rc == TPM2_RC_INITIALIZE || rc == TPM2_RC_SUCCESS)
807 return rc;
808 }
809
810 return rc;
811 }
812
813 /**
814 * tpm2_probe() - probe for the TPM 2.0 protocol
815 * @chip: a &tpm_chip instance
816 *
817 * Send an idempotent TPM 2.0 command and see whether there is TPM2 chip in the
818 * other end based on the response tag. The flag TPM_CHIP_FLAG_TPM2 is set by
819 * this function if this is the case.
820 *
821 * Return:
822 * 0 on success,
823 * -errno otherwise
824 */
tpm2_probe(struct tpm_chip * chip)825 int tpm2_probe(struct tpm_chip *chip)
826 {
827 struct tpm_output_header *out;
828 struct tpm_buf buf;
829 int rc;
830
831 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
832 if (rc)
833 return rc;
834 tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
835 tpm_buf_append_u32(&buf, TPM_PT_TOTAL_COMMANDS);
836 tpm_buf_append_u32(&buf, 1);
837 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, NULL);
838 /* We ignore TPM return codes on purpose. */
839 if (rc >= 0) {
840 out = (struct tpm_output_header *)buf.data;
841 if (be16_to_cpu(out->tag) == TPM2_ST_NO_SESSIONS)
842 chip->flags |= TPM_CHIP_FLAG_TPM2;
843 }
844 tpm_buf_destroy(&buf);
845 return 0;
846 }
847 EXPORT_SYMBOL_GPL(tpm2_probe);
848
849 struct tpm2_pcr_selection {
850 __be16 hash_alg;
851 u8 size_of_select;
852 u8 pcr_select[3];
853 } __packed;
854
tpm2_get_pcr_allocation(struct tpm_chip * chip)855 static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
856 {
857 struct tpm2_pcr_selection pcr_selection;
858 struct tpm_buf buf;
859 void *marker;
860 void *end;
861 void *pcr_select_offset;
862 unsigned int count;
863 u32 sizeof_pcr_selection;
864 u32 rsp_len;
865 int rc;
866 int i = 0;
867
868 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
869 if (rc)
870 return rc;
871
872 tpm_buf_append_u32(&buf, TPM2_CAP_PCRS);
873 tpm_buf_append_u32(&buf, 0);
874 tpm_buf_append_u32(&buf, 1);
875
876 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 9, 0,
877 "get tpm pcr allocation");
878 if (rc)
879 goto out;
880
881 count = be32_to_cpup(
882 (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]);
883
884 if (count > ARRAY_SIZE(chip->active_banks)) {
885 rc = -ENODEV;
886 goto out;
887 }
888
889 marker = &buf.data[TPM_HEADER_SIZE + 9];
890
891 rsp_len = be32_to_cpup((__be32 *)&buf.data[2]);
892 end = &buf.data[rsp_len];
893
894 for (i = 0; i < count; i++) {
895 pcr_select_offset = marker +
896 offsetof(struct tpm2_pcr_selection, size_of_select);
897 if (pcr_select_offset >= end) {
898 rc = -EFAULT;
899 break;
900 }
901
902 memcpy(&pcr_selection, marker, sizeof(pcr_selection));
903 chip->active_banks[i] = be16_to_cpu(pcr_selection.hash_alg);
904 sizeof_pcr_selection = sizeof(pcr_selection.hash_alg) +
905 sizeof(pcr_selection.size_of_select) +
906 pcr_selection.size_of_select;
907 marker = marker + sizeof_pcr_selection;
908 }
909
910 out:
911 if (i < ARRAY_SIZE(chip->active_banks))
912 chip->active_banks[i] = TPM2_ALG_ERROR;
913
914 tpm_buf_destroy(&buf);
915
916 return rc;
917 }
918
tpm2_get_cc_attrs_tbl(struct tpm_chip * chip)919 static int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
920 {
921 struct tpm_buf buf;
922 u32 nr_commands;
923 __be32 *attrs;
924 u32 cc;
925 int i;
926 int rc;
927
928 rc = tpm2_get_tpm_pt(chip, TPM_PT_TOTAL_COMMANDS, &nr_commands, NULL);
929 if (rc)
930 goto out;
931
932 if (nr_commands > 0xFFFFF) {
933 rc = -EFAULT;
934 goto out;
935 }
936
937 chip->cc_attrs_tbl = devm_kcalloc(&chip->dev, 4, nr_commands,
938 GFP_KERNEL);
939
940 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
941 if (rc)
942 goto out;
943
944 tpm_buf_append_u32(&buf, TPM2_CAP_COMMANDS);
945 tpm_buf_append_u32(&buf, TPM2_CC_FIRST);
946 tpm_buf_append_u32(&buf, nr_commands);
947
948 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE,
949 9 + 4 * nr_commands, 0, NULL);
950 if (rc) {
951 tpm_buf_destroy(&buf);
952 goto out;
953 }
954
955 if (nr_commands !=
956 be32_to_cpup((__be32 *)&buf.data[TPM_HEADER_SIZE + 5])) {
957 tpm_buf_destroy(&buf);
958 goto out;
959 }
960
961 chip->nr_commands = nr_commands;
962
963 attrs = (__be32 *)&buf.data[TPM_HEADER_SIZE + 9];
964 for (i = 0; i < nr_commands; i++, attrs++) {
965 chip->cc_attrs_tbl[i] = be32_to_cpup(attrs);
966 cc = chip->cc_attrs_tbl[i] & 0xFFFF;
967
968 if (cc == TPM2_CC_CONTEXT_SAVE || cc == TPM2_CC_FLUSH_CONTEXT) {
969 chip->cc_attrs_tbl[i] &=
970 ~(GENMASK(2, 0) << TPM2_CC_ATTR_CHANDLES);
971 chip->cc_attrs_tbl[i] |= 1 << TPM2_CC_ATTR_CHANDLES;
972 }
973 }
974
975 tpm_buf_destroy(&buf);
976
977 out:
978 if (rc > 0)
979 rc = -ENODEV;
980 return rc;
981 }
982
983 /**
984 * tpm2_auto_startup - Perform the standard automatic TPM initialization
985 * sequence
986 * @chip: TPM chip to use
987 *
988 * Returns 0 on success, < 0 in case of fatal error.
989 */
tpm2_auto_startup(struct tpm_chip * chip)990 int tpm2_auto_startup(struct tpm_chip *chip)
991 {
992 int rc;
993
994 rc = tpm_get_timeouts(chip);
995 if (rc)
996 goto out;
997
998 rc = tpm2_do_selftest(chip);
999 if (rc && rc != TPM2_RC_INITIALIZE)
1000 goto out;
1001
1002 if (rc == TPM2_RC_INITIALIZE) {
1003 rc = tpm_startup(chip);
1004 if (rc)
1005 goto out;
1006
1007 rc = tpm2_do_selftest(chip);
1008 if (rc)
1009 goto out;
1010 }
1011
1012 rc = tpm2_get_pcr_allocation(chip);
1013 if (rc)
1014 goto out;
1015
1016 rc = tpm2_get_cc_attrs_tbl(chip);
1017
1018 out:
1019 if (rc > 0)
1020 rc = -ENODEV;
1021 return rc;
1022 }
1023
tpm2_find_cc(struct tpm_chip * chip,u32 cc)1024 int tpm2_find_cc(struct tpm_chip *chip, u32 cc)
1025 {
1026 int i;
1027
1028 for (i = 0; i < chip->nr_commands; i++)
1029 if (cc == (chip->cc_attrs_tbl[i] & GENMASK(15, 0)))
1030 return i;
1031
1032 return -1;
1033 }
1034
