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 TPM_HEADER_SIZE +
333 offsetof(struct tpm2_get_random_out, buffer) +
334 recd) {
335 err = -EFAULT;
336 goto out;
337 }
338 memcpy(dest_ptr, out->buffer, recd);
339
340 dest_ptr += recd;
341 total += recd;
342 num_bytes -= recd;
343 } while (retries-- && total < max);
344
345 tpm_buf_destroy(&buf);
346 return total ? total : -EIO;
347 out:
348 tpm_buf_destroy(&buf);
349 return err;
350 }
351
352 /**
353 * tpm2_flush_context_cmd() - execute a TPM2_FlushContext command
354 * @chip: TPM chip to use
355 * @payload: the key data in clear and encrypted form
356 * @options: authentication values and other options
357 *
358 * Return: same as with tpm_transmit_cmd
359 */
tpm2_flush_context_cmd(struct tpm_chip * chip,u32 handle,unsigned int flags)360 void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
361 unsigned int flags)
362 {
363 struct tpm_buf buf;
364 int rc;
365
366 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
367 if (rc) {
368 dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n",
369 handle);
370 return;
371 }
372
373 tpm_buf_append_u32(&buf, handle);
374
375 (void) tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, flags,
376 "flushing context");
377
378 tpm_buf_destroy(&buf);
379 }
380
381 /**
382 * tpm_buf_append_auth() - append TPMS_AUTH_COMMAND to the buffer.
383 *
384 * @buf: an allocated tpm_buf instance
385 * @session_handle: session handle
386 * @nonce: the session nonce, may be NULL if not used
387 * @nonce_len: the session nonce length, may be 0 if not used
388 * @attributes: the session attributes
389 * @hmac: the session HMAC or password, may be NULL if not used
390 * @hmac_len: the session HMAC or password length, maybe 0 if not used
391 */
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)392 static void tpm2_buf_append_auth(struct tpm_buf *buf, u32 session_handle,
393 const u8 *nonce, u16 nonce_len,
394 u8 attributes,
395 const u8 *hmac, u16 hmac_len)
396 {
397 tpm_buf_append_u32(buf, 9 + nonce_len + hmac_len);
398 tpm_buf_append_u32(buf, session_handle);
399 tpm_buf_append_u16(buf, nonce_len);
400
401 if (nonce && nonce_len)
402 tpm_buf_append(buf, nonce, nonce_len);
403
404 tpm_buf_append_u8(buf, attributes);
405 tpm_buf_append_u16(buf, hmac_len);
406
407 if (hmac && hmac_len)
408 tpm_buf_append(buf, hmac, hmac_len);
409 }
410
411 /**
412 * tpm2_seal_trusted() - seal the payload of a trusted key
413 *
414 * @chip: TPM chip to use
415 * @payload: the key data in clear and encrypted form
416 * @options: authentication values and other options
417 *
418 * Return: < 0 on error and 0 on success.
419 */
tpm2_seal_trusted(struct tpm_chip * chip,struct trusted_key_payload * payload,struct trusted_key_options * options)420 int tpm2_seal_trusted(struct tpm_chip *chip,
421 struct trusted_key_payload *payload,
422 struct trusted_key_options *options)
423 {
424 unsigned int blob_len;
425 struct tpm_buf buf;
426 u32 hash;
427 int i;
428 int rc;
429
430 for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {
431 if (options->hash == tpm2_hash_map[i].crypto_id) {
432 hash = tpm2_hash_map[i].tpm_id;
433 break;
434 }
435 }
436
437 if (i == ARRAY_SIZE(tpm2_hash_map))
438 return -EINVAL;
439
440 rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
441 if (rc)
442 return rc;
443
444 tpm_buf_append_u32(&buf, options->keyhandle);
445 tpm2_buf_append_auth(&buf, TPM2_RS_PW,
446 NULL /* nonce */, 0,
447 0 /* session_attributes */,
448 options->keyauth /* hmac */,
449 TPM_DIGEST_SIZE);
450
451 /* sensitive */
452 tpm_buf_append_u16(&buf, 4 + TPM_DIGEST_SIZE + payload->key_len + 1);
453
454 tpm_buf_append_u16(&buf, TPM_DIGEST_SIZE);
455 tpm_buf_append(&buf, options->blobauth, TPM_DIGEST_SIZE);
456 tpm_buf_append_u16(&buf, payload->key_len + 1);
457 tpm_buf_append(&buf, payload->key, payload->key_len);
458 tpm_buf_append_u8(&buf, payload->migratable);
459
460 /* public */
461 tpm_buf_append_u16(&buf, 14 + options->policydigest_len);
462 tpm_buf_append_u16(&buf, TPM2_ALG_KEYEDHASH);
463 tpm_buf_append_u16(&buf, hash);
464
465 /* policy */
466 if (options->policydigest_len) {
467 tpm_buf_append_u32(&buf, 0);
468 tpm_buf_append_u16(&buf, options->policydigest_len);
469 tpm_buf_append(&buf, options->policydigest,
470 options->policydigest_len);
471 } else {
472 tpm_buf_append_u32(&buf, TPM2_OA_USER_WITH_AUTH);
473 tpm_buf_append_u16(&buf, 0);
474 }
475
476 /* public parameters */
477 tpm_buf_append_u16(&buf, TPM2_ALG_NULL);
478 tpm_buf_append_u16(&buf, 0);
479
480 /* outside info */
481 tpm_buf_append_u16(&buf, 0);
482
483 /* creation PCR */
484 tpm_buf_append_u32(&buf, 0);
485
486 if (buf.flags & TPM_BUF_OVERFLOW) {
487 rc = -E2BIG;
488 goto out;
489 }
490
491 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 4, 0,
492 "sealing data");
493 if (rc)
494 goto out;
495
496 blob_len = be32_to_cpup((__be32 *) &buf.data[TPM_HEADER_SIZE]);
497 if (blob_len > MAX_BLOB_SIZE) {
498 rc = -E2BIG;
499 goto out;
500 }
501 if (tpm_buf_length(&buf) < TPM_HEADER_SIZE + 4 + blob_len) {
502 rc = -EFAULT;
503 goto out;
504 }
505
506 memcpy(payload->blob, &buf.data[TPM_HEADER_SIZE + 4], blob_len);
507 payload->blob_len = blob_len;
508
509 out:
510 tpm_buf_destroy(&buf);
511
512 if (rc > 0) {
513 if (tpm2_rc_value(rc) == TPM2_RC_HASH)
514 rc = -EINVAL;
515 else
516 rc = -EPERM;
517 }
518
519 return rc;
520 }
521
522 /**
523 * tpm2_load_cmd() - execute a TPM2_Load command
524 *
525 * @chip: TPM chip to use
526 * @payload: the key data in clear and encrypted form
527 * @options: authentication values and other options
528 * @blob_handle: returned blob handle
529 * @flags: tpm transmit flags
530 *
531 * Return: 0 on success.
532 * -E2BIG on wrong payload size.
533 * -EPERM on tpm error status.
534 * < 0 error from tpm_transmit_cmd.
535 */
tpm2_load_cmd(struct tpm_chip * chip,struct trusted_key_payload * payload,struct trusted_key_options * options,u32 * blob_handle,unsigned int flags)536 static int tpm2_load_cmd(struct tpm_chip *chip,
537 struct trusted_key_payload *payload,
538 struct trusted_key_options *options,
539 u32 *blob_handle, unsigned int flags)
540 {
541 struct tpm_buf buf;
542 unsigned int private_len;
543 unsigned int public_len;
544 unsigned int blob_len;
545 int rc;
546
547 private_len = be16_to_cpup((__be16 *) &payload->blob[0]);
548 if (private_len > (payload->blob_len - 2))
549 return -E2BIG;
550
551 public_len = be16_to_cpup((__be16 *) &payload->blob[2 + private_len]);
552 blob_len = private_len + public_len + 4;
553 if (blob_len > payload->blob_len)
554 return -E2BIG;
555
556 rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
557 if (rc)
558 return rc;
559
560 tpm_buf_append_u32(&buf, options->keyhandle);
561 tpm2_buf_append_auth(&buf, TPM2_RS_PW,
562 NULL /* nonce */, 0,
563 0 /* session_attributes */,
564 options->keyauth /* hmac */,
565 TPM_DIGEST_SIZE);
566
567 tpm_buf_append(&buf, payload->blob, blob_len);
568
569 if (buf.flags & TPM_BUF_OVERFLOW) {
570 rc = -E2BIG;
571 goto out;
572 }
573
574 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 4, flags,
575 "loading blob");
576 if (!rc)
577 *blob_handle = be32_to_cpup(
578 (__be32 *) &buf.data[TPM_HEADER_SIZE]);
579
580 out:
581 tpm_buf_destroy(&buf);
582
583 if (rc > 0)
584 rc = -EPERM;
585
586 return rc;
587 }
588
589 /**
590 * tpm2_unseal_cmd() - execute a TPM2_Unload command
591 *
592 * @chip: TPM chip to use
593 * @payload: the key data in clear and encrypted form
594 * @options: authentication values and other options
595 * @blob_handle: blob handle
596 * @flags: tpm_transmit_cmd flags
597 *
598 * Return: 0 on success
599 * -EPERM on tpm error status
600 * < 0 error from tpm_transmit_cmd
601 */
tpm2_unseal_cmd(struct tpm_chip * chip,struct trusted_key_payload * payload,struct trusted_key_options * options,u32 blob_handle,unsigned int flags)602 static int tpm2_unseal_cmd(struct tpm_chip *chip,
603 struct trusted_key_payload *payload,
604 struct trusted_key_options *options,
605 u32 blob_handle, unsigned int flags)
606 {
607 struct tpm_buf buf;
608 u16 data_len;
609 u8 *data;
610 int rc;
611
612 rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
613 if (rc)
614 return rc;
615
616 tpm_buf_append_u32(&buf, blob_handle);
617 tpm2_buf_append_auth(&buf,
618 options->policyhandle ?
619 options->policyhandle : TPM2_RS_PW,
620 NULL /* nonce */, 0,
621 TPM2_SA_CONTINUE_SESSION,
622 options->blobauth /* hmac */,
623 TPM_DIGEST_SIZE);
624
625 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 6, flags,
626 "unsealing");
627 if (rc > 0)
628 rc = -EPERM;
629
630 if (!rc) {
631 data_len = be16_to_cpup(
632 (__be16 *) &buf.data[TPM_HEADER_SIZE + 4]);
633 if (data_len < MIN_KEY_SIZE || data_len > MAX_KEY_SIZE + 1) {
634 rc = -EFAULT;
635 goto out;
636 }
637
638 if (tpm_buf_length(&buf) < TPM_HEADER_SIZE + 6 + data_len) {
639 rc = -EFAULT;
640 goto out;
641 }
642 data = &buf.data[TPM_HEADER_SIZE + 6];
643
644 memcpy(payload->key, data, data_len - 1);
645 payload->key_len = data_len - 1;
646 payload->migratable = data[data_len - 1];
647 }
648
649 out:
650 tpm_buf_destroy(&buf);
651 return rc;
652 }
653
654 /**
655 * tpm2_unseal_trusted() - unseal the payload of a trusted key
656 *
657 * @chip: TPM chip to use
658 * @payload: the key data in clear and encrypted form
659 * @options: authentication values and other options
660 *
661 * Return: Same as with tpm_transmit_cmd.
662 */
tpm2_unseal_trusted(struct tpm_chip * chip,struct trusted_key_payload * payload,struct trusted_key_options * options)663 int tpm2_unseal_trusted(struct tpm_chip *chip,
664 struct trusted_key_payload *payload,
665 struct trusted_key_options *options)
666 {
667 u32 blob_handle;
668 int rc;
669
670 mutex_lock(&chip->tpm_mutex);
671 rc = tpm2_load_cmd(chip, payload, options, &blob_handle,
672 TPM_TRANSMIT_UNLOCKED);
673 if (rc)
674 goto out;
675
676 rc = tpm2_unseal_cmd(chip, payload, options, blob_handle,
677 TPM_TRANSMIT_UNLOCKED);
678 tpm2_flush_context_cmd(chip, blob_handle, TPM_TRANSMIT_UNLOCKED);
679 out:
680 mutex_unlock(&chip->tpm_mutex);
681 return rc;
682 }
683
684 struct tpm2_get_cap_out {
685 u8 more_data;
686 __be32 subcap_id;
687 __be32 property_cnt;
688 __be32 property_id;
689 __be32 value;
690 } __packed;
691
692 /**
693 * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
694 * @chip: a &tpm_chip instance
695 * @property_id: property ID.
696 * @value: output variable.
697 * @desc: passed to tpm_transmit_cmd()
698 *
699 * Return:
700 * 0 on success,
701 * -errno or a TPM return code otherwise
702 */
tpm2_get_tpm_pt(struct tpm_chip * chip,u32 property_id,u32 * value,const char * desc)703 ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id, u32 *value,
704 const char *desc)
705 {
706 struct tpm2_get_cap_out *out;
707 struct tpm_buf buf;
708 int rc;
709
710 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
711 if (rc)
712 return rc;
713 tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
714 tpm_buf_append_u32(&buf, property_id);
715 tpm_buf_append_u32(&buf, 1);
716 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, NULL);
717 if (!rc) {
718 out = (struct tpm2_get_cap_out *)
719 &buf.data[TPM_HEADER_SIZE];
720 /*
721 * To prevent failing boot up of some systems, Infineon TPM2.0
722 * returns SUCCESS on TPM2_Startup in field upgrade mode. Also
723 * the TPM2_Getcapability command returns a zero length list
724 * in field upgrade mode.
725 */
726 if (be32_to_cpu(out->property_cnt) > 0)
727 *value = be32_to_cpu(out->value);
728 else
729 rc = -ENODATA;
730 }
731 tpm_buf_destroy(&buf);
732 return rc;
733 }
734 EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
735
736 /**
737 * tpm2_shutdown() - send a TPM shutdown command
738 *
739 * Sends a TPM shutdown command. The shutdown command is used in call
740 * sites where the system is going down. If it fails, there is not much
741 * that can be done except print an error message.
742 *
743 * @chip: a &tpm_chip instance
744 * @shutdown_type: TPM_SU_CLEAR or TPM_SU_STATE.
745 */
tpm2_shutdown(struct tpm_chip * chip,u16 shutdown_type)746 void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
747 {
748 struct tpm_buf buf;
749 int rc;
750
751 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SHUTDOWN);
752 if (rc)
753 return;
754 tpm_buf_append_u16(&buf, shutdown_type);
755 tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
756 "stopping the TPM");
757 tpm_buf_destroy(&buf);
758 }
759
760 /*
761 * tpm2_calc_ordinal_duration() - maximum duration for a command
762 *
763 * @chip: TPM chip to use.
764 * @ordinal: command code number.
765 *
766 * Return: maximum duration for a command
767 */
tpm2_calc_ordinal_duration(struct tpm_chip * chip,u32 ordinal)768 unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
769 {
770 int index = TPM_UNDEFINED;
771 int duration = 0;
772
773 if (ordinal >= TPM2_CC_FIRST && ordinal <= TPM2_CC_LAST)
774 index = tpm2_ordinal_duration[ordinal - TPM2_CC_FIRST];
775
776 if (index != TPM_UNDEFINED)
777 duration = chip->duration[index];
778
779 if (duration <= 0)
780 duration = msecs_to_jiffies(TPM2_DURATION_DEFAULT);
781
782 return duration;
783 }
784 EXPORT_SYMBOL_GPL(tpm2_calc_ordinal_duration);
785
786 /**
787 * tpm2_do_selftest() - ensure that all self tests have passed
788 *
789 * @chip: TPM chip to use
790 *
791 * Return: Same as with tpm_transmit_cmd.
792 *
793 * The TPM can either run all self tests synchronously and then return
794 * RC_SUCCESS once all tests were successful. Or it can choose to run the tests
795 * asynchronously and return RC_TESTING immediately while the self tests still
796 * execute in the background. This function handles both cases and waits until
797 * all tests have completed.
798 */
tpm2_do_selftest(struct tpm_chip * chip)799 static int tpm2_do_selftest(struct tpm_chip *chip)
800 {
801 struct tpm_buf buf;
802 int full;
803 int rc;
804
805 for (full = 0; full < 2; full++) {
806 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SELF_TEST);
807 if (rc)
808 return rc;
809
810 tpm_buf_append_u8(&buf, full);
811 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
812 "attempting the self test");
813 tpm_buf_destroy(&buf);
814
815 if (rc == TPM2_RC_TESTING)
816 rc = TPM2_RC_SUCCESS;
817 if (rc == TPM2_RC_INITIALIZE || rc == TPM2_RC_SUCCESS)
818 return rc;
819 }
820
821 return rc;
822 }
823
824 /**
825 * tpm2_probe() - probe for the TPM 2.0 protocol
826 * @chip: a &tpm_chip instance
827 *
828 * Send an idempotent TPM 2.0 command and see whether there is TPM2 chip in the
829 * other end based on the response tag. The flag TPM_CHIP_FLAG_TPM2 is set by
830 * this function if this is the case.
831 *
832 * Return:
833 * 0 on success,
834 * -errno otherwise
835 */
tpm2_probe(struct tpm_chip * chip)836 int tpm2_probe(struct tpm_chip *chip)
837 {
838 struct tpm_output_header *out;
839 struct tpm_buf buf;
840 int rc;
841
842 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
843 if (rc)
844 return rc;
845 tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
846 tpm_buf_append_u32(&buf, TPM_PT_TOTAL_COMMANDS);
847 tpm_buf_append_u32(&buf, 1);
848 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, NULL);
849 /* We ignore TPM return codes on purpose. */
850 if (rc >= 0) {
851 out = (struct tpm_output_header *)buf.data;
852 if (be16_to_cpu(out->tag) == TPM2_ST_NO_SESSIONS)
853 chip->flags |= TPM_CHIP_FLAG_TPM2;
854 }
855 tpm_buf_destroy(&buf);
856 return 0;
857 }
858 EXPORT_SYMBOL_GPL(tpm2_probe);
859
860 struct tpm2_pcr_selection {
861 __be16 hash_alg;
862 u8 size_of_select;
863 u8 pcr_select[3];
864 } __packed;
865
tpm2_get_pcr_allocation(struct tpm_chip * chip)866 static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
867 {
868 struct tpm2_pcr_selection pcr_selection;
869 struct tpm_buf buf;
870 void *marker;
871 void *end;
872 void *pcr_select_offset;
873 unsigned int count;
874 u32 sizeof_pcr_selection;
875 u32 rsp_len;
876 int rc;
877 int i = 0;
878
879 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
880 if (rc)
881 return rc;
882
883 tpm_buf_append_u32(&buf, TPM2_CAP_PCRS);
884 tpm_buf_append_u32(&buf, 0);
885 tpm_buf_append_u32(&buf, 1);
886
887 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 9, 0,
888 "get tpm pcr allocation");
889 if (rc)
890 goto out;
891
892 count = be32_to_cpup(
893 (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]);
894
895 if (count > ARRAY_SIZE(chip->active_banks)) {
896 rc = -ENODEV;
897 goto out;
898 }
899
900 marker = &buf.data[TPM_HEADER_SIZE + 9];
901
902 rsp_len = be32_to_cpup((__be32 *)&buf.data[2]);
903 end = &buf.data[rsp_len];
904
905 for (i = 0; i < count; i++) {
906 pcr_select_offset = marker +
907 offsetof(struct tpm2_pcr_selection, size_of_select);
908 if (pcr_select_offset >= end) {
909 rc = -EFAULT;
910 break;
911 }
912
913 memcpy(&pcr_selection, marker, sizeof(pcr_selection));
914 chip->active_banks[i] = be16_to_cpu(pcr_selection.hash_alg);
915 sizeof_pcr_selection = sizeof(pcr_selection.hash_alg) +
916 sizeof(pcr_selection.size_of_select) +
917 pcr_selection.size_of_select;
918 marker = marker + sizeof_pcr_selection;
919 }
920
921 out:
922 if (i < ARRAY_SIZE(chip->active_banks))
923 chip->active_banks[i] = TPM2_ALG_ERROR;
924
925 tpm_buf_destroy(&buf);
926
927 return rc;
928 }
929
tpm2_get_cc_attrs_tbl(struct tpm_chip * chip)930 static int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
931 {
932 struct tpm_buf buf;
933 u32 nr_commands;
934 __be32 *attrs;
935 u32 cc;
936 int i;
937 int rc;
938
939 rc = tpm2_get_tpm_pt(chip, TPM_PT_TOTAL_COMMANDS, &nr_commands, NULL);
940 if (rc)
941 goto out;
942
943 if (nr_commands > 0xFFFFF) {
944 rc = -EFAULT;
945 goto out;
946 }
947
948 chip->cc_attrs_tbl = devm_kcalloc(&chip->dev, 4, nr_commands,
949 GFP_KERNEL);
950 if (!chip->cc_attrs_tbl) {
951 rc = -ENOMEM;
952 goto out;
953 }
954
955 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
956 if (rc)
957 goto out;
958
959 tpm_buf_append_u32(&buf, TPM2_CAP_COMMANDS);
960 tpm_buf_append_u32(&buf, TPM2_CC_FIRST);
961 tpm_buf_append_u32(&buf, nr_commands);
962
963 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE,
964 9 + 4 * nr_commands, 0, NULL);
965 if (rc) {
966 tpm_buf_destroy(&buf);
967 goto out;
968 }
969
970 if (nr_commands !=
971 be32_to_cpup((__be32 *)&buf.data[TPM_HEADER_SIZE + 5])) {
972 rc = -EFAULT;
973 tpm_buf_destroy(&buf);
974 goto out;
975 }
976
977 chip->nr_commands = nr_commands;
978
979 attrs = (__be32 *)&buf.data[TPM_HEADER_SIZE + 9];
980 for (i = 0; i < nr_commands; i++, attrs++) {
981 chip->cc_attrs_tbl[i] = be32_to_cpup(attrs);
982 cc = chip->cc_attrs_tbl[i] & 0xFFFF;
983
984 if (cc == TPM2_CC_CONTEXT_SAVE || cc == TPM2_CC_FLUSH_CONTEXT) {
985 chip->cc_attrs_tbl[i] &=
986 ~(GENMASK(2, 0) << TPM2_CC_ATTR_CHANDLES);
987 chip->cc_attrs_tbl[i] |= 1 << TPM2_CC_ATTR_CHANDLES;
988 }
989 }
990
991 tpm_buf_destroy(&buf);
992
993 out:
994 if (rc > 0)
995 rc = -ENODEV;
996 return rc;
997 }
998
999 /**
1000 * tpm2_auto_startup - Perform the standard automatic TPM initialization
1001 * sequence
1002 * @chip: TPM chip to use
1003 *
1004 * Returns 0 on success, < 0 in case of fatal error.
1005 */
tpm2_auto_startup(struct tpm_chip * chip)1006 int tpm2_auto_startup(struct tpm_chip *chip)
1007 {
1008 int rc;
1009
1010 rc = tpm_get_timeouts(chip);
1011 if (rc)
1012 goto out;
1013
1014 rc = tpm2_do_selftest(chip);
1015 if (rc && rc != TPM2_RC_INITIALIZE)
1016 goto out;
1017
1018 if (rc == TPM2_RC_INITIALIZE) {
1019 rc = tpm_startup(chip);
1020 if (rc)
1021 goto out;
1022
1023 rc = tpm2_do_selftest(chip);
1024 if (rc)
1025 goto out;
1026 }
1027
1028 rc = tpm2_get_pcr_allocation(chip);
1029 if (rc)
1030 goto out;
1031
1032 rc = tpm2_get_cc_attrs_tbl(chip);
1033
1034 out:
1035 if (rc > 0)
1036 rc = -ENODEV;
1037 return rc;
1038 }
1039
tpm2_find_cc(struct tpm_chip * chip,u32 cc)1040 int tpm2_find_cc(struct tpm_chip *chip, u32 cc)
1041 {
1042 int i;
1043
1044 for (i = 0; i < chip->nr_commands; i++)
1045 if (cc == (chip->cc_attrs_tbl[i] & GENMASK(15, 0)))
1046 return i;
1047
1048 return -1;
1049 }
1050