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_startup_in {
31 __be16 startup_type;
32 } __packed;
33
34 struct tpm2_self_test_in {
35 u8 full_test;
36 } __packed;
37
38 struct tpm2_get_tpm_pt_in {
39 __be32 cap_id;
40 __be32 property_id;
41 __be32 property_cnt;
42 } __packed;
43
44 struct tpm2_get_tpm_pt_out {
45 u8 more_data;
46 __be32 subcap_id;
47 __be32 property_cnt;
48 __be32 property_id;
49 __be32 value;
50 } __packed;
51
52 struct tpm2_get_random_in {
53 __be16 size;
54 } __packed;
55
56 struct tpm2_get_random_out {
57 __be16 size;
58 u8 buffer[TPM_MAX_RNG_DATA];
59 } __packed;
60
61 union tpm2_cmd_params {
62 struct tpm2_startup_in startup_in;
63 struct tpm2_self_test_in selftest_in;
64 struct tpm2_get_tpm_pt_in get_tpm_pt_in;
65 struct tpm2_get_tpm_pt_out get_tpm_pt_out;
66 struct tpm2_get_random_in getrandom_in;
67 struct tpm2_get_random_out getrandom_out;
68 };
69
70 struct tpm2_cmd {
71 tpm_cmd_header header;
72 union tpm2_cmd_params params;
73 } __packed;
74
75 struct tpm2_hash {
76 unsigned int crypto_id;
77 unsigned int tpm_id;
78 };
79
80 static struct tpm2_hash tpm2_hash_map[] = {
81 {HASH_ALGO_SHA1, TPM2_ALG_SHA1},
82 {HASH_ALGO_SHA256, TPM2_ALG_SHA256},
83 {HASH_ALGO_SHA384, TPM2_ALG_SHA384},
84 {HASH_ALGO_SHA512, TPM2_ALG_SHA512},
85 {HASH_ALGO_SM3_256, TPM2_ALG_SM3_256},
86 };
87
88 /*
89 * Array with one entry per ordinal defining the maximum amount
90 * of time the chip could take to return the result. The values
91 * of the SHORT, MEDIUM, and LONG durations are taken from the
92 * PC Client Profile (PTP) specification.
93 */
94 static const u8 tpm2_ordinal_duration[TPM2_CC_LAST - TPM2_CC_FIRST + 1] = {
95 TPM_UNDEFINED, /* 11F */
96 TPM_UNDEFINED, /* 120 */
97 TPM_LONG, /* 121 */
98 TPM_UNDEFINED, /* 122 */
99 TPM_UNDEFINED, /* 123 */
100 TPM_UNDEFINED, /* 124 */
101 TPM_UNDEFINED, /* 125 */
102 TPM_UNDEFINED, /* 126 */
103 TPM_UNDEFINED, /* 127 */
104 TPM_UNDEFINED, /* 128 */
105 TPM_LONG, /* 129 */
106 TPM_UNDEFINED, /* 12a */
107 TPM_UNDEFINED, /* 12b */
108 TPM_UNDEFINED, /* 12c */
109 TPM_UNDEFINED, /* 12d */
110 TPM_UNDEFINED, /* 12e */
111 TPM_UNDEFINED, /* 12f */
112 TPM_UNDEFINED, /* 130 */
113 TPM_UNDEFINED, /* 131 */
114 TPM_UNDEFINED, /* 132 */
115 TPM_UNDEFINED, /* 133 */
116 TPM_UNDEFINED, /* 134 */
117 TPM_UNDEFINED, /* 135 */
118 TPM_UNDEFINED, /* 136 */
119 TPM_UNDEFINED, /* 137 */
120 TPM_UNDEFINED, /* 138 */
121 TPM_UNDEFINED, /* 139 */
122 TPM_UNDEFINED, /* 13a */
123 TPM_UNDEFINED, /* 13b */
124 TPM_UNDEFINED, /* 13c */
125 TPM_UNDEFINED, /* 13d */
126 TPM_MEDIUM, /* 13e */
127 TPM_UNDEFINED, /* 13f */
128 TPM_UNDEFINED, /* 140 */
129 TPM_UNDEFINED, /* 141 */
130 TPM_UNDEFINED, /* 142 */
131 TPM_LONG, /* 143 */
132 TPM_MEDIUM, /* 144 */
133 TPM_UNDEFINED, /* 145 */
134 TPM_UNDEFINED, /* 146 */
135 TPM_UNDEFINED, /* 147 */
136 TPM_UNDEFINED, /* 148 */
137 TPM_UNDEFINED, /* 149 */
138 TPM_UNDEFINED, /* 14a */
139 TPM_UNDEFINED, /* 14b */
140 TPM_UNDEFINED, /* 14c */
141 TPM_UNDEFINED, /* 14d */
142 TPM_LONG, /* 14e */
143 TPM_UNDEFINED, /* 14f */
144 TPM_UNDEFINED, /* 150 */
145 TPM_UNDEFINED, /* 151 */
146 TPM_UNDEFINED, /* 152 */
147 TPM_UNDEFINED, /* 153 */
148 TPM_UNDEFINED, /* 154 */
149 TPM_UNDEFINED, /* 155 */
150 TPM_UNDEFINED, /* 156 */
151 TPM_UNDEFINED, /* 157 */
152 TPM_UNDEFINED, /* 158 */
153 TPM_UNDEFINED, /* 159 */
154 TPM_UNDEFINED, /* 15a */
155 TPM_UNDEFINED, /* 15b */
156 TPM_MEDIUM, /* 15c */
157 TPM_UNDEFINED, /* 15d */
158 TPM_UNDEFINED, /* 15e */
159 TPM_UNDEFINED, /* 15f */
160 TPM_UNDEFINED, /* 160 */
161 TPM_UNDEFINED, /* 161 */
162 TPM_UNDEFINED, /* 162 */
163 TPM_UNDEFINED, /* 163 */
164 TPM_UNDEFINED, /* 164 */
165 TPM_UNDEFINED, /* 165 */
166 TPM_UNDEFINED, /* 166 */
167 TPM_UNDEFINED, /* 167 */
168 TPM_UNDEFINED, /* 168 */
169 TPM_UNDEFINED, /* 169 */
170 TPM_UNDEFINED, /* 16a */
171 TPM_UNDEFINED, /* 16b */
172 TPM_UNDEFINED, /* 16c */
173 TPM_UNDEFINED, /* 16d */
174 TPM_UNDEFINED, /* 16e */
175 TPM_UNDEFINED, /* 16f */
176 TPM_UNDEFINED, /* 170 */
177 TPM_UNDEFINED, /* 171 */
178 TPM_UNDEFINED, /* 172 */
179 TPM_UNDEFINED, /* 173 */
180 TPM_UNDEFINED, /* 174 */
181 TPM_UNDEFINED, /* 175 */
182 TPM_UNDEFINED, /* 176 */
183 TPM_LONG, /* 177 */
184 TPM_UNDEFINED, /* 178 */
185 TPM_UNDEFINED, /* 179 */
186 TPM_MEDIUM, /* 17a */
187 TPM_LONG, /* 17b */
188 TPM_UNDEFINED, /* 17c */
189 TPM_UNDEFINED, /* 17d */
190 TPM_UNDEFINED, /* 17e */
191 TPM_UNDEFINED, /* 17f */
192 TPM_UNDEFINED, /* 180 */
193 TPM_UNDEFINED, /* 181 */
194 TPM_MEDIUM, /* 182 */
195 TPM_UNDEFINED, /* 183 */
196 TPM_UNDEFINED, /* 184 */
197 TPM_MEDIUM, /* 185 */
198 TPM_MEDIUM, /* 186 */
199 TPM_UNDEFINED, /* 187 */
200 TPM_UNDEFINED, /* 188 */
201 TPM_UNDEFINED, /* 189 */
202 TPM_UNDEFINED, /* 18a */
203 TPM_UNDEFINED, /* 18b */
204 TPM_UNDEFINED, /* 18c */
205 TPM_UNDEFINED, /* 18d */
206 TPM_UNDEFINED, /* 18e */
207 TPM_UNDEFINED /* 18f */
208 };
209
210 struct tpm2_pcr_read_out {
211 __be32 update_cnt;
212 __be32 pcr_selects_cnt;
213 __be16 hash_alg;
214 u8 pcr_select_size;
215 u8 pcr_select[TPM2_PCR_SELECT_MIN];
216 __be32 digests_cnt;
217 __be16 digest_size;
218 u8 digest[];
219 } __packed;
220
221 /**
222 * tpm2_pcr_read() - read a PCR value
223 * @chip: TPM chip to use.
224 * @pcr_idx: index of the PCR to read.
225 * @res_buf: buffer to store the resulting hash.
226 *
227 * Return: Same as with tpm_transmit_cmd.
228 */
tpm2_pcr_read(struct tpm_chip * chip,int pcr_idx,u8 * res_buf)229 int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
230 {
231 int rc;
232 struct tpm_buf buf;
233 struct tpm2_pcr_read_out *out;
234 u8 pcr_select[TPM2_PCR_SELECT_MIN] = {0};
235
236 if (pcr_idx >= TPM2_PLATFORM_PCR)
237 return -EINVAL;
238
239 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ);
240 if (rc)
241 return rc;
242
243 pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
244
245 tpm_buf_append_u32(&buf, 1);
246 tpm_buf_append_u16(&buf, TPM2_ALG_SHA1);
247 tpm_buf_append_u8(&buf, TPM2_PCR_SELECT_MIN);
248 tpm_buf_append(&buf, (const unsigned char *)pcr_select,
249 sizeof(pcr_select));
250
251 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
252 res_buf ? "attempting to read a pcr value" : NULL);
253 if (rc == 0 && res_buf) {
254 out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE];
255 memcpy(res_buf, out->digest, SHA1_DIGEST_SIZE);
256 }
257
258 tpm_buf_destroy(&buf);
259 return rc;
260 }
261
262 struct tpm2_null_auth_area {
263 __be32 handle;
264 __be16 nonce_size;
265 u8 attributes;
266 __be16 auth_size;
267 } __packed;
268
269 /**
270 * tpm2_pcr_extend() - extend a PCR value
271 *
272 * @chip: TPM chip to use.
273 * @pcr_idx: index of the PCR.
274 * @count: number of digests passed.
275 * @digests: list of pcr banks and corresponding digest values to extend.
276 *
277 * Return: Same as with tpm_transmit_cmd.
278 */
tpm2_pcr_extend(struct tpm_chip * chip,int pcr_idx,u32 count,struct tpm2_digest * digests)279 int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, u32 count,
280 struct tpm2_digest *digests)
281 {
282 struct tpm_buf buf;
283 struct tpm2_null_auth_area auth_area;
284 int rc;
285 int i;
286 int j;
287
288 if (count > ARRAY_SIZE(chip->active_banks))
289 return -EINVAL;
290
291 rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
292 if (rc)
293 return rc;
294
295 tpm_buf_append_u32(&buf, pcr_idx);
296
297 auth_area.handle = cpu_to_be32(TPM2_RS_PW);
298 auth_area.nonce_size = 0;
299 auth_area.attributes = 0;
300 auth_area.auth_size = 0;
301
302 tpm_buf_append_u32(&buf, sizeof(struct tpm2_null_auth_area));
303 tpm_buf_append(&buf, (const unsigned char *)&auth_area,
304 sizeof(auth_area));
305 tpm_buf_append_u32(&buf, count);
306
307 for (i = 0; i < count; i++) {
308 for (j = 0; j < ARRAY_SIZE(tpm2_hash_map); j++) {
309 if (digests[i].alg_id != tpm2_hash_map[j].tpm_id)
310 continue;
311 tpm_buf_append_u16(&buf, digests[i].alg_id);
312 tpm_buf_append(&buf, (const unsigned char
313 *)&digests[i].digest,
314 hash_digest_size[tpm2_hash_map[j].crypto_id]);
315 }
316 }
317
318 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
319 "attempting extend a PCR value");
320
321 tpm_buf_destroy(&buf);
322
323 return rc;
324 }
325
326
327 #define TPM2_GETRANDOM_IN_SIZE \
328 (sizeof(struct tpm_input_header) + \
329 sizeof(struct tpm2_get_random_in))
330
331 static const struct tpm_input_header tpm2_getrandom_header = {
332 .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
333 .length = cpu_to_be32(TPM2_GETRANDOM_IN_SIZE),
334 .ordinal = cpu_to_be32(TPM2_CC_GET_RANDOM)
335 };
336
337 /**
338 * tpm2_get_random() - get random bytes from the TPM RNG
339 *
340 * @chip: TPM chip to use
341 * @out: destination buffer for the random bytes
342 * @max: the max number of bytes to write to @out
343 *
344 * Return:
345 * Size of the output buffer, or -EIO on error.
346 */
tpm2_get_random(struct tpm_chip * chip,u8 * out,size_t max)347 int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
348 {
349 struct tpm2_cmd cmd;
350 u32 recd, rlength;
351 u32 num_bytes;
352 int err;
353 int total = 0;
354 int retries = 5;
355 u8 *dest = out;
356
357 num_bytes = min_t(u32, max, sizeof(cmd.params.getrandom_out.buffer));
358
359 if (!out || !num_bytes ||
360 max > sizeof(cmd.params.getrandom_out.buffer))
361 return -EINVAL;
362
363 do {
364 cmd.header.in = tpm2_getrandom_header;
365 cmd.params.getrandom_in.size = cpu_to_be16(num_bytes);
366
367 err = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd),
368 offsetof(struct tpm2_get_random_out,
369 buffer),
370 0, "attempting get random");
371 if (err)
372 break;
373
374 recd = min_t(u32, be16_to_cpu(cmd.params.getrandom_out.size),
375 num_bytes);
376 rlength = be32_to_cpu(cmd.header.out.length);
377 if (rlength < offsetof(struct tpm2_get_random_out, buffer) +
378 recd)
379 return -EFAULT;
380 memcpy(dest, cmd.params.getrandom_out.buffer, recd);
381
382 dest += recd;
383 total += recd;
384 num_bytes -= recd;
385 } while (retries-- && total < max);
386
387 return total ? total : -EIO;
388 }
389
390 #define TPM2_GET_TPM_PT_IN_SIZE \
391 (sizeof(struct tpm_input_header) + \
392 sizeof(struct tpm2_get_tpm_pt_in))
393
394 #define TPM2_GET_TPM_PT_OUT_BODY_SIZE \
395 sizeof(struct tpm2_get_tpm_pt_out)
396
397 static const struct tpm_input_header tpm2_get_tpm_pt_header = {
398 .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
399 .length = cpu_to_be32(TPM2_GET_TPM_PT_IN_SIZE),
400 .ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
401 };
402
403 /**
404 * tpm2_flush_context_cmd() - execute a TPM2_FlushContext command
405 * @chip: TPM chip to use
406 * @payload: the key data in clear and encrypted form
407 * @options: authentication values and other options
408 *
409 * Return: same as with tpm_transmit_cmd
410 */
tpm2_flush_context_cmd(struct tpm_chip * chip,u32 handle,unsigned int flags)411 void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
412 unsigned int flags)
413 {
414 struct tpm_buf buf;
415 int rc;
416
417 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
418 if (rc) {
419 dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n",
420 handle);
421 return;
422 }
423
424 tpm_buf_append_u32(&buf, handle);
425
426 (void) tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, flags,
427 "flushing context");
428
429 tpm_buf_destroy(&buf);
430 }
431
432 /**
433 * tpm_buf_append_auth() - append TPMS_AUTH_COMMAND to the buffer.
434 *
435 * @buf: an allocated tpm_buf instance
436 * @session_handle: session handle
437 * @nonce: the session nonce, may be NULL if not used
438 * @nonce_len: the session nonce length, may be 0 if not used
439 * @attributes: the session attributes
440 * @hmac: the session HMAC or password, may be NULL if not used
441 * @hmac_len: the session HMAC or password length, maybe 0 if not used
442 */
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)443 static void tpm2_buf_append_auth(struct tpm_buf *buf, u32 session_handle,
444 const u8 *nonce, u16 nonce_len,
445 u8 attributes,
446 const u8 *hmac, u16 hmac_len)
447 {
448 tpm_buf_append_u32(buf, 9 + nonce_len + hmac_len);
449 tpm_buf_append_u32(buf, session_handle);
450 tpm_buf_append_u16(buf, nonce_len);
451
452 if (nonce && nonce_len)
453 tpm_buf_append(buf, nonce, nonce_len);
454
455 tpm_buf_append_u8(buf, attributes);
456 tpm_buf_append_u16(buf, hmac_len);
457
458 if (hmac && hmac_len)
459 tpm_buf_append(buf, hmac, hmac_len);
460 }
461
462 /**
463 * tpm2_seal_trusted() - seal the payload of a trusted key
464 *
465 * @chip: TPM chip to use
466 * @payload: the key data in clear and encrypted form
467 * @options: authentication values and other options
468 *
469 * Return: < 0 on error and 0 on success.
470 */
tpm2_seal_trusted(struct tpm_chip * chip,struct trusted_key_payload * payload,struct trusted_key_options * options)471 int tpm2_seal_trusted(struct tpm_chip *chip,
472 struct trusted_key_payload *payload,
473 struct trusted_key_options *options)
474 {
475 unsigned int blob_len;
476 struct tpm_buf buf;
477 u32 hash, rlength;
478 int i;
479 int rc;
480
481 for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {
482 if (options->hash == tpm2_hash_map[i].crypto_id) {
483 hash = tpm2_hash_map[i].tpm_id;
484 break;
485 }
486 }
487
488 if (i == ARRAY_SIZE(tpm2_hash_map))
489 return -EINVAL;
490
491 rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
492 if (rc)
493 return rc;
494
495 tpm_buf_append_u32(&buf, options->keyhandle);
496 tpm2_buf_append_auth(&buf, TPM2_RS_PW,
497 NULL /* nonce */, 0,
498 0 /* session_attributes */,
499 options->keyauth /* hmac */,
500 TPM_DIGEST_SIZE);
501
502 /* sensitive */
503 tpm_buf_append_u16(&buf, 4 + TPM_DIGEST_SIZE + payload->key_len + 1);
504
505 tpm_buf_append_u16(&buf, TPM_DIGEST_SIZE);
506 tpm_buf_append(&buf, options->blobauth, TPM_DIGEST_SIZE);
507 tpm_buf_append_u16(&buf, payload->key_len + 1);
508 tpm_buf_append(&buf, payload->key, payload->key_len);
509 tpm_buf_append_u8(&buf, payload->migratable);
510
511 /* public */
512 tpm_buf_append_u16(&buf, 14 + options->policydigest_len);
513 tpm_buf_append_u16(&buf, TPM2_ALG_KEYEDHASH);
514 tpm_buf_append_u16(&buf, hash);
515
516 /* policy */
517 if (options->policydigest_len) {
518 tpm_buf_append_u32(&buf, 0);
519 tpm_buf_append_u16(&buf, options->policydigest_len);
520 tpm_buf_append(&buf, options->policydigest,
521 options->policydigest_len);
522 } else {
523 tpm_buf_append_u32(&buf, TPM2_OA_USER_WITH_AUTH);
524 tpm_buf_append_u16(&buf, 0);
525 }
526
527 /* public parameters */
528 tpm_buf_append_u16(&buf, TPM2_ALG_NULL);
529 tpm_buf_append_u16(&buf, 0);
530
531 /* outside info */
532 tpm_buf_append_u16(&buf, 0);
533
534 /* creation PCR */
535 tpm_buf_append_u32(&buf, 0);
536
537 if (buf.flags & TPM_BUF_OVERFLOW) {
538 rc = -E2BIG;
539 goto out;
540 }
541
542 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 4, 0,
543 "sealing data");
544 if (rc)
545 goto out;
546
547 blob_len = be32_to_cpup((__be32 *) &buf.data[TPM_HEADER_SIZE]);
548 if (blob_len > MAX_BLOB_SIZE) {
549 rc = -E2BIG;
550 goto out;
551 }
552 rlength = be32_to_cpu(((struct tpm2_cmd *)&buf)->header.out.length);
553 if (rlength < TPM_HEADER_SIZE + 4 + blob_len) {
554 rc = -EFAULT;
555 goto out;
556 }
557
558 memcpy(payload->blob, &buf.data[TPM_HEADER_SIZE + 4], blob_len);
559 payload->blob_len = blob_len;
560
561 out:
562 tpm_buf_destroy(&buf);
563
564 if (rc > 0) {
565 if (tpm2_rc_value(rc) == TPM2_RC_HASH)
566 rc = -EINVAL;
567 else
568 rc = -EPERM;
569 }
570
571 return rc;
572 }
573
574 /**
575 * tpm2_load_cmd() - execute a TPM2_Load command
576 *
577 * @chip: TPM chip to use
578 * @payload: the key data in clear and encrypted form
579 * @options: authentication values and other options
580 * @blob_handle: returned blob handle
581 * @flags: tpm transmit flags
582 *
583 * Return: 0 on success.
584 * -E2BIG on wrong payload size.
585 * -EPERM on tpm error status.
586 * < 0 error from tpm_transmit_cmd.
587 */
tpm2_load_cmd(struct tpm_chip * chip,struct trusted_key_payload * payload,struct trusted_key_options * options,u32 * blob_handle,unsigned int flags)588 static int tpm2_load_cmd(struct tpm_chip *chip,
589 struct trusted_key_payload *payload,
590 struct trusted_key_options *options,
591 u32 *blob_handle, unsigned int flags)
592 {
593 struct tpm_buf buf;
594 unsigned int private_len;
595 unsigned int public_len;
596 unsigned int blob_len;
597 int rc;
598
599 private_len = be16_to_cpup((__be16 *) &payload->blob[0]);
600 if (private_len > (payload->blob_len - 2))
601 return -E2BIG;
602
603 public_len = be16_to_cpup((__be16 *) &payload->blob[2 + private_len]);
604 blob_len = private_len + public_len + 4;
605 if (blob_len > payload->blob_len)
606 return -E2BIG;
607
608 rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
609 if (rc)
610 return rc;
611
612 tpm_buf_append_u32(&buf, options->keyhandle);
613 tpm2_buf_append_auth(&buf, TPM2_RS_PW,
614 NULL /* nonce */, 0,
615 0 /* session_attributes */,
616 options->keyauth /* hmac */,
617 TPM_DIGEST_SIZE);
618
619 tpm_buf_append(&buf, payload->blob, blob_len);
620
621 if (buf.flags & TPM_BUF_OVERFLOW) {
622 rc = -E2BIG;
623 goto out;
624 }
625
626 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 4, flags,
627 "loading blob");
628 if (!rc)
629 *blob_handle = be32_to_cpup(
630 (__be32 *) &buf.data[TPM_HEADER_SIZE]);
631
632 out:
633 tpm_buf_destroy(&buf);
634
635 if (rc > 0)
636 rc = -EPERM;
637
638 return rc;
639 }
640
641 /**
642 * tpm2_unseal_cmd() - execute a TPM2_Unload command
643 *
644 * @chip: TPM chip to use
645 * @payload: the key data in clear and encrypted form
646 * @options: authentication values and other options
647 * @blob_handle: blob handle
648 * @flags: tpm_transmit_cmd flags
649 *
650 * Return: 0 on success
651 * -EPERM on tpm error status
652 * < 0 error from tpm_transmit_cmd
653 */
tpm2_unseal_cmd(struct tpm_chip * chip,struct trusted_key_payload * payload,struct trusted_key_options * options,u32 blob_handle,unsigned int flags)654 static int tpm2_unseal_cmd(struct tpm_chip *chip,
655 struct trusted_key_payload *payload,
656 struct trusted_key_options *options,
657 u32 blob_handle, unsigned int flags)
658 {
659 struct tpm_buf buf;
660 u16 data_len;
661 u8 *data;
662 int rc;
663 u32 rlength;
664
665 rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
666 if (rc)
667 return rc;
668
669 tpm_buf_append_u32(&buf, blob_handle);
670 tpm2_buf_append_auth(&buf,
671 options->policyhandle ?
672 options->policyhandle : TPM2_RS_PW,
673 NULL /* nonce */, 0,
674 TPM2_SA_CONTINUE_SESSION,
675 options->blobauth /* hmac */,
676 TPM_DIGEST_SIZE);
677
678 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 6, flags,
679 "unsealing");
680 if (rc > 0)
681 rc = -EPERM;
682
683 if (!rc) {
684 data_len = be16_to_cpup(
685 (__be16 *) &buf.data[TPM_HEADER_SIZE + 4]);
686 if (data_len < MIN_KEY_SIZE || data_len > MAX_KEY_SIZE + 1) {
687 rc = -EFAULT;
688 goto out;
689 }
690
691 rlength = be32_to_cpu(((struct tpm2_cmd *)&buf)
692 ->header.out.length);
693 if (rlength < TPM_HEADER_SIZE + 6 + data_len) {
694 rc = -EFAULT;
695 goto out;
696 }
697 data = &buf.data[TPM_HEADER_SIZE + 6];
698
699 memcpy(payload->key, data, data_len - 1);
700 payload->key_len = data_len - 1;
701 payload->migratable = data[data_len - 1];
702 }
703
704 out:
705 tpm_buf_destroy(&buf);
706 return rc;
707 }
708
709 /**
710 * tpm2_unseal_trusted() - unseal the payload of a trusted key
711 *
712 * @chip: TPM chip to use
713 * @payload: the key data in clear and encrypted form
714 * @options: authentication values and other options
715 *
716 * Return: Same as with tpm_transmit_cmd.
717 */
tpm2_unseal_trusted(struct tpm_chip * chip,struct trusted_key_payload * payload,struct trusted_key_options * options)718 int tpm2_unseal_trusted(struct tpm_chip *chip,
719 struct trusted_key_payload *payload,
720 struct trusted_key_options *options)
721 {
722 u32 blob_handle;
723 int rc;
724
725 mutex_lock(&chip->tpm_mutex);
726 rc = tpm2_load_cmd(chip, payload, options, &blob_handle,
727 TPM_TRANSMIT_UNLOCKED);
728 if (rc)
729 goto out;
730
731 rc = tpm2_unseal_cmd(chip, payload, options, blob_handle,
732 TPM_TRANSMIT_UNLOCKED);
733 tpm2_flush_context_cmd(chip, blob_handle, TPM_TRANSMIT_UNLOCKED);
734 out:
735 mutex_unlock(&chip->tpm_mutex);
736 return rc;
737 }
738
739 /**
740 * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
741 * @chip: TPM chip to use.
742 * @property_id: property ID.
743 * @value: output variable.
744 * @desc: passed to tpm_transmit_cmd()
745 *
746 * Return: Same as with tpm_transmit_cmd.
747 */
tpm2_get_tpm_pt(struct tpm_chip * chip,u32 property_id,u32 * value,const char * desc)748 ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id, u32 *value,
749 const char *desc)
750 {
751 struct tpm2_cmd cmd;
752 int rc;
753
754 cmd.header.in = tpm2_get_tpm_pt_header;
755 cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
756 cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(property_id);
757 cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
758
759 rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd),
760 TPM2_GET_TPM_PT_OUT_BODY_SIZE, 0, desc);
761 if (!rc)
762 *value = be32_to_cpu(cmd.params.get_tpm_pt_out.value);
763
764 return rc;
765 }
766 EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
767
768 #define TPM2_SHUTDOWN_IN_SIZE \
769 (sizeof(struct tpm_input_header) + \
770 sizeof(struct tpm2_startup_in))
771
772 static const struct tpm_input_header tpm2_shutdown_header = {
773 .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
774 .length = cpu_to_be32(TPM2_SHUTDOWN_IN_SIZE),
775 .ordinal = cpu_to_be32(TPM2_CC_SHUTDOWN)
776 };
777
778 /**
779 * tpm2_shutdown() - send shutdown command to the TPM chip
780 *
781 * @chip: TPM chip to use.
782 * @shutdown_type: shutdown type. The value is either
783 * TPM_SU_CLEAR or TPM_SU_STATE.
784 */
tpm2_shutdown(struct tpm_chip * chip,u16 shutdown_type)785 void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
786 {
787 struct tpm2_cmd cmd;
788 int rc;
789
790 cmd.header.in = tpm2_shutdown_header;
791 cmd.params.startup_in.startup_type = cpu_to_be16(shutdown_type);
792
793 rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0,
794 "stopping the TPM");
795
796 /* In places where shutdown command is sent there's no much we can do
797 * except print the error code on a system failure.
798 */
799 if (rc < 0 && rc != -EPIPE)
800 dev_warn(&chip->dev, "transmit returned %d while stopping the TPM",
801 rc);
802 }
803
804 /*
805 * tpm2_calc_ordinal_duration() - maximum duration for a command
806 *
807 * @chip: TPM chip to use.
808 * @ordinal: command code number.
809 *
810 * Return: maximum duration for a command
811 */
tpm2_calc_ordinal_duration(struct tpm_chip * chip,u32 ordinal)812 unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
813 {
814 int index = TPM_UNDEFINED;
815 int duration = 0;
816
817 if (ordinal >= TPM2_CC_FIRST && ordinal <= TPM2_CC_LAST)
818 index = tpm2_ordinal_duration[ordinal - TPM2_CC_FIRST];
819
820 if (index != TPM_UNDEFINED)
821 duration = chip->duration[index];
822
823 if (duration <= 0)
824 duration = 2 * 60 * HZ;
825
826 return duration;
827 }
828 EXPORT_SYMBOL_GPL(tpm2_calc_ordinal_duration);
829
830 #define TPM2_SELF_TEST_IN_SIZE \
831 (sizeof(struct tpm_input_header) + \
832 sizeof(struct tpm2_self_test_in))
833
834 static const struct tpm_input_header tpm2_selftest_header = {
835 .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
836 .length = cpu_to_be32(TPM2_SELF_TEST_IN_SIZE),
837 .ordinal = cpu_to_be32(TPM2_CC_SELF_TEST)
838 };
839
840 /**
841 * tpm2_continue_selftest() - start a self test
842 *
843 * @chip: TPM chip to use
844 * @full: test all commands instead of testing only those that were not
845 * previously tested.
846 *
847 * Return: Same as with tpm_transmit_cmd with exception of RC_TESTING.
848 */
tpm2_start_selftest(struct tpm_chip * chip,bool full)849 static int tpm2_start_selftest(struct tpm_chip *chip, bool full)
850 {
851 int rc;
852 struct tpm2_cmd cmd;
853
854 cmd.header.in = tpm2_selftest_header;
855 cmd.params.selftest_in.full_test = full;
856
857 rc = tpm_transmit_cmd(chip, NULL, &cmd, TPM2_SELF_TEST_IN_SIZE, 0, 0,
858 "continue selftest");
859
860 /* At least some prototype chips seem to give RC_TESTING error
861 * immediately. This is a workaround for that.
862 */
863 if (rc == TPM2_RC_TESTING) {
864 dev_warn(&chip->dev, "Got RC_TESTING, ignoring\n");
865 rc = 0;
866 }
867
868 return rc;
869 }
870
871 /**
872 * tpm2_do_selftest() - run a full self test
873 *
874 * @chip: TPM chip to use
875 *
876 * Return: Same as with tpm_transmit_cmd.
877 *
878 * During the self test TPM2 commands return with the error code RC_TESTING.
879 * Waiting is done by issuing PCR read until it executes successfully.
880 */
tpm2_do_selftest(struct tpm_chip * chip)881 static int tpm2_do_selftest(struct tpm_chip *chip)
882 {
883 int rc;
884 unsigned int loops;
885 unsigned int delay_msec = 100;
886 unsigned long duration;
887 int i;
888
889 duration = tpm2_calc_ordinal_duration(chip, TPM2_CC_SELF_TEST);
890
891 loops = jiffies_to_msecs(duration) / delay_msec;
892
893 rc = tpm2_start_selftest(chip, true);
894 if (rc)
895 return rc;
896
897 for (i = 0; i < loops; i++) {
898 /* Attempt to read a PCR value */
899 rc = tpm2_pcr_read(chip, 0, NULL);
900 if (rc < 0)
901 break;
902
903 if (rc != TPM2_RC_TESTING)
904 break;
905
906 tpm_msleep(delay_msec);
907 }
908
909 return rc;
910 }
911
912 /**
913 * tpm2_probe() - probe TPM 2.0
914 * @chip: TPM chip to use
915 *
916 * Return: < 0 error and 0 on success.
917 *
918 * Send idempotent TPM 2.0 command and see whether TPM 2.0 chip replied based on
919 * the reply tag.
920 */
tpm2_probe(struct tpm_chip * chip)921 int tpm2_probe(struct tpm_chip *chip)
922 {
923 struct tpm2_cmd cmd;
924 int rc;
925
926 cmd.header.in = tpm2_get_tpm_pt_header;
927 cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
928 cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(0x100);
929 cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
930
931 rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0, NULL);
932 if (rc < 0)
933 return rc;
934
935 if (be16_to_cpu(cmd.header.out.tag) == TPM2_ST_NO_SESSIONS)
936 chip->flags |= TPM_CHIP_FLAG_TPM2;
937
938 return 0;
939 }
940 EXPORT_SYMBOL_GPL(tpm2_probe);
941
942 struct tpm2_pcr_selection {
943 __be16 hash_alg;
944 u8 size_of_select;
945 u8 pcr_select[3];
946 } __packed;
947
tpm2_get_pcr_allocation(struct tpm_chip * chip)948 static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
949 {
950 struct tpm2_pcr_selection pcr_selection;
951 struct tpm_buf buf;
952 void *marker;
953 void *end;
954 void *pcr_select_offset;
955 unsigned int count;
956 u32 sizeof_pcr_selection;
957 u32 rsp_len;
958 int rc;
959 int i = 0;
960
961 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
962 if (rc)
963 return rc;
964
965 tpm_buf_append_u32(&buf, TPM2_CAP_PCRS);
966 tpm_buf_append_u32(&buf, 0);
967 tpm_buf_append_u32(&buf, 1);
968
969 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 9, 0,
970 "get tpm pcr allocation");
971 if (rc)
972 goto out;
973
974 count = be32_to_cpup(
975 (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]);
976
977 if (count > ARRAY_SIZE(chip->active_banks)) {
978 rc = -ENODEV;
979 goto out;
980 }
981
982 marker = &buf.data[TPM_HEADER_SIZE + 9];
983
984 rsp_len = be32_to_cpup((__be32 *)&buf.data[2]);
985 end = &buf.data[rsp_len];
986
987 for (i = 0; i < count; i++) {
988 pcr_select_offset = marker +
989 offsetof(struct tpm2_pcr_selection, size_of_select);
990 if (pcr_select_offset >= end) {
991 rc = -EFAULT;
992 break;
993 }
994
995 memcpy(&pcr_selection, marker, sizeof(pcr_selection));
996 chip->active_banks[i] = be16_to_cpu(pcr_selection.hash_alg);
997 sizeof_pcr_selection = sizeof(pcr_selection.hash_alg) +
998 sizeof(pcr_selection.size_of_select) +
999 pcr_selection.size_of_select;
1000 marker = marker + sizeof_pcr_selection;
1001 }
1002
1003 out:
1004 if (i < ARRAY_SIZE(chip->active_banks))
1005 chip->active_banks[i] = TPM2_ALG_ERROR;
1006
1007 tpm_buf_destroy(&buf);
1008
1009 return rc;
1010 }
1011
tpm2_get_cc_attrs_tbl(struct tpm_chip * chip)1012 static int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
1013 {
1014 struct tpm_buf buf;
1015 u32 nr_commands;
1016 u32 *attrs;
1017 u32 cc;
1018 int i;
1019 int rc;
1020
1021 rc = tpm2_get_tpm_pt(chip, TPM_PT_TOTAL_COMMANDS, &nr_commands, NULL);
1022 if (rc)
1023 goto out;
1024
1025 if (nr_commands > 0xFFFFF) {
1026 rc = -EFAULT;
1027 goto out;
1028 }
1029
1030 chip->cc_attrs_tbl = devm_kzalloc(&chip->dev, 4 * nr_commands,
1031 GFP_KERNEL);
1032 if (!chip->cc_attrs_tbl) {
1033 rc = -ENOMEM;
1034 goto out;
1035 }
1036
1037 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
1038 if (rc)
1039 goto out;
1040
1041 tpm_buf_append_u32(&buf, TPM2_CAP_COMMANDS);
1042 tpm_buf_append_u32(&buf, TPM2_CC_FIRST);
1043 tpm_buf_append_u32(&buf, nr_commands);
1044
1045 rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE,
1046 9 + 4 * nr_commands, 0, NULL);
1047 if (rc) {
1048 tpm_buf_destroy(&buf);
1049 goto out;
1050 }
1051
1052 if (nr_commands !=
1053 be32_to_cpup((__be32 *)&buf.data[TPM_HEADER_SIZE + 5])) {
1054 tpm_buf_destroy(&buf);
1055 goto out;
1056 }
1057
1058 chip->nr_commands = nr_commands;
1059
1060 attrs = (u32 *)&buf.data[TPM_HEADER_SIZE + 9];
1061 for (i = 0; i < nr_commands; i++, attrs++) {
1062 chip->cc_attrs_tbl[i] = be32_to_cpup(attrs);
1063 cc = chip->cc_attrs_tbl[i] & 0xFFFF;
1064
1065 if (cc == TPM2_CC_CONTEXT_SAVE || cc == TPM2_CC_FLUSH_CONTEXT) {
1066 chip->cc_attrs_tbl[i] &=
1067 ~(GENMASK(2, 0) << TPM2_CC_ATTR_CHANDLES);
1068 chip->cc_attrs_tbl[i] |= 1 << TPM2_CC_ATTR_CHANDLES;
1069 }
1070 }
1071
1072 tpm_buf_destroy(&buf);
1073
1074 out:
1075 if (rc > 0)
1076 rc = -ENODEV;
1077 return rc;
1078 }
1079
1080 /**
1081 * tpm2_auto_startup - Perform the standard automatic TPM initialization
1082 * sequence
1083 * @chip: TPM chip to use
1084 *
1085 * Returns 0 on success, < 0 in case of fatal error.
1086 */
tpm2_auto_startup(struct tpm_chip * chip)1087 int tpm2_auto_startup(struct tpm_chip *chip)
1088 {
1089 int rc;
1090
1091 rc = tpm_get_timeouts(chip);
1092 if (rc)
1093 goto out;
1094
1095 rc = tpm2_do_selftest(chip);
1096 if (rc != 0 && rc != TPM2_RC_INITIALIZE) {
1097 dev_err(&chip->dev, "TPM self test failed\n");
1098 goto out;
1099 }
1100
1101 if (rc == TPM2_RC_INITIALIZE) {
1102 rc = tpm_startup(chip);
1103 if (rc)
1104 goto out;
1105
1106 rc = tpm2_do_selftest(chip);
1107 if (rc) {
1108 dev_err(&chip->dev, "TPM self test failed\n");
1109 goto out;
1110 }
1111 }
1112
1113 rc = tpm2_get_pcr_allocation(chip);
1114 if (rc)
1115 goto out;
1116
1117 rc = tpm2_get_cc_attrs_tbl(chip);
1118
1119 out:
1120 if (rc > 0)
1121 rc = -ENODEV;
1122 return rc;
1123 }
1124
tpm2_find_cc(struct tpm_chip * chip,u32 cc)1125 int tpm2_find_cc(struct tpm_chip *chip, u32 cc)
1126 {
1127 int i;
1128
1129 for (i = 0; i < chip->nr_commands; i++)
1130 if (cc == (chip->cc_attrs_tbl[i] & GENMASK(15, 0)))
1131 return i;
1132
1133 return -1;
1134 }
1135