drivers/char/tpm/tpm2-cmd.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2014, 2015 Intel Corporation
   4  *
   5  * Authors:
   6  * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
   7  *
   8  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
   9  *
  10  * This file contains TPM2 protocol implementations of the commands
  11  * used by the kernel internally.
  12  */
  13
  14 #include "tpm.h"
  15 #include <crypto/hash_info.h>
  16
  17 static struct tpm2_hash tpm2_hash_map[] = {
  18         {HASH_ALGO_SHA1, TPM_ALG_SHA1},
  19         {HASH_ALGO_SHA256, TPM_ALG_SHA256},
  20         {HASH_ALGO_SHA384, TPM_ALG_SHA384},
  21         {HASH_ALGO_SHA512, TPM_ALG_SHA512},
  22         {HASH_ALGO_SM3_256, TPM_ALG_SM3_256},
  23 };
  24
  25 int tpm2_get_timeouts(struct tpm_chip *chip)
  26 {
  27         /* Fixed timeouts for TPM2 */
  28         chip->timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
  29         chip->timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
  30         chip->timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
  31         chip->timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
  32
  33         /* PTP spec timeouts */
  34         chip->duration[TPM_SHORT] = msecs_to_jiffies(TPM2_DURATION_SHORT);
  35         chip->duration[TPM_MEDIUM] = msecs_to_jiffies(TPM2_DURATION_MEDIUM);
  36         chip->duration[TPM_LONG] = msecs_to_jiffies(TPM2_DURATION_LONG);
  37
  38         /* Key creation commands long timeouts */
  39         chip->duration[TPM_LONG_LONG] =
  40                 msecs_to_jiffies(TPM2_DURATION_LONG_LONG);
  41
  42         chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
  43
  44         return 0;
  45 }
  46
  47 /**
  48  * tpm2_ordinal_duration_index() - returns an index to the chip duration table
  49  * @ordinal: TPM command ordinal.
  50  *
  51  * The function returns an index to the chip duration table
  52  * (enum tpm_duration), that describes the maximum amount of
  53  * time the chip could take to return the result for a  particular ordinal.
  54  *
  55  * The values of the MEDIUM, and LONG durations are taken
  56  * from the PC Client Profile (PTP) specification (750, 2000 msec)
  57  *
  58  * LONG_LONG is for commands that generates keys which empirically takes
  59  * a longer time on some systems.
  60  *
  61  * Return:
  62  * * TPM_MEDIUM
  63  * * TPM_LONG
  64  * * TPM_LONG_LONG
  65  * * TPM_UNDEFINED
  66  */
  67 static u8 tpm2_ordinal_duration_index(u32 ordinal)
  68 {
  69         switch (ordinal) {
  70         /* Startup */
  71         case TPM2_CC_STARTUP:                 /* 144 */
  72                 return TPM_MEDIUM;
  73
  74         case TPM2_CC_SELF_TEST:               /* 143 */
  75                 return TPM_LONG;
  76
  77         case TPM2_CC_GET_RANDOM:              /* 17B */
  78                 return TPM_LONG;
  79
  80         case TPM2_CC_SEQUENCE_UPDATE:         /* 15C */
  81                 return TPM_MEDIUM;
  82         case TPM2_CC_SEQUENCE_COMPLETE:       /* 13E */
  83                 return TPM_MEDIUM;
  84         case TPM2_CC_EVENT_SEQUENCE_COMPLETE: /* 185 */
  85                 return TPM_MEDIUM;
  86         case TPM2_CC_HASH_SEQUENCE_START:     /* 186 */
  87                 return TPM_MEDIUM;
  88
  89         case TPM2_CC_VERIFY_SIGNATURE:        /* 177 */
  90                 return TPM_LONG;
  91
  92         case TPM2_CC_PCR_EXTEND:              /* 182 */
  93                 return TPM_MEDIUM;
  94
  95         case TPM2_CC_HIERARCHY_CONTROL:       /* 121 */
  96                 return TPM_LONG;
  97         case TPM2_CC_HIERARCHY_CHANGE_AUTH:   /* 129 */
  98                 return TPM_LONG;
  99
 100         case TPM2_CC_GET_CAPABILITY:          /* 17A */
 101                 return TPM_MEDIUM;
 102
 103         case TPM2_CC_NV_READ:                 /* 14E */
 104                 return TPM_LONG;
 105
 106         case TPM2_CC_CREATE_PRIMARY:          /* 131 */
 107                 return TPM_LONG_LONG;
 108         case TPM2_CC_CREATE:                  /* 153 */
 109                 return TPM_LONG_LONG;
 110         case TPM2_CC_CREATE_LOADED:           /* 191 */
 111                 return TPM_LONG_LONG;
 112
 113         default:
 114                 return TPM_UNDEFINED;
 115         }
 116 }
 117
 118 /**
 119  * tpm2_calc_ordinal_duration() - calculate the maximum command duration
 120  * @chip:    TPM chip to use.
 121  * @ordinal: TPM command ordinal.
 122  *
 123  * The function returns the maximum amount of time the chip could take
 124  * to return the result for a particular ordinal in jiffies.
 125  *
 126  * Return: A maximal duration time for an ordinal in jiffies.
 127  */
 128 unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
 129 {
 130         unsigned int index;
 131
 132         index = tpm2_ordinal_duration_index(ordinal);
 133
 134         if (index != TPM_UNDEFINED)
 135                 return chip->duration[index];
 136         else
 137                 return msecs_to_jiffies(TPM2_DURATION_DEFAULT);
 138 }
 139
 140
 141 struct tpm2_pcr_read_out {
 142         __be32  update_cnt;
 143         __be32  pcr_selects_cnt;
 144         __be16  hash_alg;
 145         u8      pcr_select_size;
 146         u8      pcr_select[TPM2_PCR_SELECT_MIN];
 147         __be32  digests_cnt;
 148         __be16  digest_size;
 149         u8      digest[];
 150 } __packed;
 151
 152 /**
 153  * tpm2_pcr_read() - read a PCR value
 154  * @chip:       TPM chip to use.
 155  * @pcr_idx:    index of the PCR to read.
 156  * @digest:     PCR bank and buffer current PCR value is written to.
 157  * @digest_size_ptr:    pointer to variable that stores the digest size.
 158  *
 159  * Return: Same as with tpm_transmit_cmd.
 160  */
 161 int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
 162                   struct tpm_digest *digest, u16 *digest_size_ptr)
 163 {
 164         int i;
 165         int rc;
 166         struct tpm_buf buf;
 167         struct tpm2_pcr_read_out *out;
 168         u8 pcr_select[TPM2_PCR_SELECT_MIN] = {0};
 169         u16 digest_size;
 170         u16 expected_digest_size = 0;
 171
 172         if (pcr_idx >= TPM2_PLATFORM_PCR)
 173                 return -EINVAL;
 174
 175         if (!digest_size_ptr) {
 176                 for (i = 0; i < chip->nr_allocated_banks &&
 177                      chip->allocated_banks[i].alg_id != digest->alg_id; i++)
 178                         ;
 179
 180                 if (i == chip->nr_allocated_banks)
 181                         return -EINVAL;
 182
 183                 expected_digest_size = chip->allocated_banks[i].digest_size;
 184         }
 185
 186         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ);
 187         if (rc)
 188                 return rc;
 189
 190         pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
 191
 192         tpm_buf_append_u32(&buf, 1);
 193         tpm_buf_append_u16(&buf, digest->alg_id);
 194         tpm_buf_append_u8(&buf, TPM2_PCR_SELECT_MIN);
 195         tpm_buf_append(&buf, (const unsigned char *)pcr_select,
 196                        sizeof(pcr_select));
 197
 198         rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to read a pcr value");
 199         if (rc)
 200                 goto out;
 201
 202         out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE];
 203         digest_size = be16_to_cpu(out->digest_size);
 204         if (digest_size > sizeof(digest->digest) ||
 205             (!digest_size_ptr && digest_size != expected_digest_size)) {
 206                 rc = -EINVAL;
 207                 goto out;
 208         }
 209
 210         if (digest_size_ptr)
 211                 *digest_size_ptr = digest_size;
 212
 213         memcpy(digest->digest, out->digest, digest_size);
 214 out:
 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  * @digests:    list of pcr banks and corresponding digest values to extend.
 232  *
 233  * Return: Same as with tpm_transmit_cmd.
 234  */
 235 int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
 236                     struct tpm_digest *digests)
 237 {
 238         struct tpm_buf buf;
 239         struct tpm2_null_auth_area auth_area;
 240         int rc;
 241         int i;
 242
 243         rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
 244         if (rc)
 245                 return rc;
 246
 247         tpm_buf_append_u32(&buf, pcr_idx);
 248
 249         auth_area.handle = cpu_to_be32(TPM2_RS_PW);
 250         auth_area.nonce_size = 0;
 251         auth_area.attributes = 0;
 252         auth_area.auth_size = 0;
 253
 254         tpm_buf_append_u32(&buf, sizeof(struct tpm2_null_auth_area));
 255         tpm_buf_append(&buf, (const unsigned char *)&auth_area,
 256                        sizeof(auth_area));
 257         tpm_buf_append_u32(&buf, chip->nr_allocated_banks);
 258
 259         for (i = 0; i < chip->nr_allocated_banks; i++) {
 260                 tpm_buf_append_u16(&buf, digests[i].alg_id);
 261                 tpm_buf_append(&buf, (const unsigned char *)&digests[i].digest,
 262                                chip->allocated_banks[i].digest_size);
 263         }
 264
 265         rc = tpm_transmit_cmd(chip, &buf, 0, "attempting extend a PCR value");
 266
 267         tpm_buf_destroy(&buf);
 268
 269         return rc;
 270 }
 271
 272 struct tpm2_get_random_out {
 273         __be16 size;
 274         u8 buffer[TPM_MAX_RNG_DATA];
 275 } __packed;
 276
 277 /**
 278  * tpm2_get_random() - get random bytes from the TPM RNG
 279  *
 280  * @chip:       a &tpm_chip instance
 281  * @dest:       destination buffer
 282  * @max:        the max number of random bytes to pull
 283  *
 284  * Return:
 285  *   size of the buffer on success,
 286  *   -errno otherwise (positive TPM return codes are masked to -EIO)
 287  */
 288 int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
 289 {
 290         struct tpm2_get_random_out *out;
 291         struct tpm_buf buf;
 292         u32 recd;
 293         u32 num_bytes = max;
 294         int err;
 295         int total = 0;
 296         int retries = 5;
 297         u8 *dest_ptr = dest;
 298
 299         if (!num_bytes || max > TPM_MAX_RNG_DATA)
 300                 return -EINVAL;
 301
 302         err = tpm_buf_init(&buf, 0, 0);
 303         if (err)
 304                 return err;
 305
 306         do {
 307                 tpm_buf_reset(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_RANDOM);
 308                 tpm_buf_append_u16(&buf, num_bytes);
 309                 err = tpm_transmit_cmd(chip, &buf,
 310                                        offsetof(struct tpm2_get_random_out,
 311                                                 buffer),
 312                                        "attempting get random");
 313                 if (err) {
 314                         if (err > 0)
 315                                 err = -EIO;
 316                         goto out;
 317                 }
 318
 319                 out = (struct tpm2_get_random_out *)
 320                         &buf.data[TPM_HEADER_SIZE];
 321                 recd = min_t(u32, be16_to_cpu(out->size), num_bytes);
 322                 if (tpm_buf_length(&buf) <
 323                     TPM_HEADER_SIZE +
 324                     offsetof(struct tpm2_get_random_out, buffer) +
 325                     recd) {
 326                         err = -EFAULT;
 327                         goto out;
 328                 }
 329                 memcpy(dest_ptr, out->buffer, recd);
 330
 331                 dest_ptr += recd;
 332                 total += recd;
 333                 num_bytes -= recd;
 334         } while (retries-- && total < max);
 335
 336         tpm_buf_destroy(&buf);
 337         return total ? total : -EIO;
 338 out:
 339         tpm_buf_destroy(&buf);
 340         return err;
 341 }
 342
 343 /**
 344  * tpm2_flush_context() - execute a TPM2_FlushContext command
 345  * @chip:       TPM chip to use
 346  * @handle:     context handle
 347  */
 348 void tpm2_flush_context(struct tpm_chip *chip, u32 handle)
 349 {
 350         struct tpm_buf buf;
 351         int rc;
 352
 353         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
 354         if (rc) {
 355                 dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n",
 356                          handle);
 357                 return;
 358         }
 359
 360         tpm_buf_append_u32(&buf, handle);
 361
 362         tpm_transmit_cmd(chip, &buf, 0, "flushing context");
 363         tpm_buf_destroy(&buf);
 364 }
 365
 366 struct tpm2_get_cap_out {
 367         u8 more_data;
 368         __be32 subcap_id;
 369         __be32 property_cnt;
 370         __be32 property_id;
 371         __be32 value;
 372 } __packed;
 373
 374 /**
 375  * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
 376  * @chip:               a &tpm_chip instance
 377  * @property_id:        property ID.
 378  * @value:              output variable.
 379  * @desc:               passed to tpm_transmit_cmd()
 380  *
 381  * Return:
 382  *   0 on success,
 383  *   -errno or a TPM return code otherwise
 384  */
 385 ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
 386                         const char *desc)
 387 {
 388         struct tpm2_get_cap_out *out;
 389         struct tpm_buf buf;
 390         int rc;
 391
 392         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
 393         if (rc)
 394                 return rc;
 395         tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
 396         tpm_buf_append_u32(&buf, property_id);
 397         tpm_buf_append_u32(&buf, 1);
 398         rc = tpm_transmit_cmd(chip, &buf, 0, NULL);
 399         if (!rc) {
 400                 out = (struct tpm2_get_cap_out *)
 401                         &buf.data[TPM_HEADER_SIZE];
 402                 *value = be32_to_cpu(out->value);
 403         }
 404         tpm_buf_destroy(&buf);
 405         return rc;
 406 }
 407 EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
 408
 409 /**
 410  * tpm2_shutdown() - send a TPM shutdown command
 411  *
 412  * Sends a TPM shutdown command. The shutdown command is used in call
 413  * sites where the system is going down. If it fails, there is not much
 414  * that can be done except print an error message.
 415  *
 416  * @chip:               a &tpm_chip instance
 417  * @shutdown_type:      TPM_SU_CLEAR or TPM_SU_STATE.
 418  */
 419 void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
 420 {
 421         struct tpm_buf buf;
 422         int rc;
 423
 424         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SHUTDOWN);
 425         if (rc)
 426                 return;
 427         tpm_buf_append_u16(&buf, shutdown_type);
 428         tpm_transmit_cmd(chip, &buf, 0, "stopping the TPM");
 429         tpm_buf_destroy(&buf);
 430 }
 431
 432 /**
 433  * tpm2_do_selftest() - ensure that all self tests have passed
 434  *
 435  * @chip: TPM chip to use
 436  *
 437  * Return: Same as with tpm_transmit_cmd.
 438  *
 439  * The TPM can either run all self tests synchronously and then return
 440  * RC_SUCCESS once all tests were successful. Or it can choose to run the tests
 441  * asynchronously and return RC_TESTING immediately while the self tests still
 442  * execute in the background. This function handles both cases and waits until
 443  * all tests have completed.
 444  */
 445 static int tpm2_do_selftest(struct tpm_chip *chip)
 446 {
 447         struct tpm_buf buf;
 448         int full;
 449         int rc;
 450
 451         for (full = 0; full < 2; full++) {
 452                 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SELF_TEST);
 453                 if (rc)
 454                         return rc;
 455
 456                 tpm_buf_append_u8(&buf, full);
 457                 rc = tpm_transmit_cmd(chip, &buf, 0,
 458                                       "attempting the self test");
 459                 tpm_buf_destroy(&buf);
 460
 461                 if (rc == TPM2_RC_TESTING)
 462                         rc = TPM2_RC_SUCCESS;
 463                 if (rc == TPM2_RC_INITIALIZE || rc == TPM2_RC_SUCCESS)
 464                         return rc;
 465         }
 466
 467         return rc;
 468 }
 469
 470 /**
 471  * tpm2_probe() - probe for the TPM 2.0 protocol
 472  * @chip:       a &tpm_chip instance
 473  *
 474  * Send an idempotent TPM 2.0 command and see whether there is TPM2 chip in the
 475  * other end based on the response tag. The flag TPM_CHIP_FLAG_TPM2 is set by
 476  * this function if this is the case.
 477  *
 478  * Return:
 479  *   0 on success,
 480  *   -errno otherwise
 481  */
 482 int tpm2_probe(struct tpm_chip *chip)
 483 {
 484         struct tpm_header *out;
 485         struct tpm_buf buf;
 486         int rc;
 487
 488         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
 489         if (rc)
 490                 return rc;
 491         tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
 492         tpm_buf_append_u32(&buf, TPM_PT_TOTAL_COMMANDS);
 493         tpm_buf_append_u32(&buf, 1);
 494         rc = tpm_transmit_cmd(chip, &buf, 0, NULL);
 495         /* We ignore TPM return codes on purpose. */
 496         if (rc >=  0) {
 497                 out = (struct tpm_header *)buf.data;
 498                 if (be16_to_cpu(out->tag) == TPM2_ST_NO_SESSIONS)
 499                         chip->flags |= TPM_CHIP_FLAG_TPM2;
 500         }
 501         tpm_buf_destroy(&buf);
 502         return 0;
 503 }
 504 EXPORT_SYMBOL_GPL(tpm2_probe);
 505
 506 static int tpm2_init_bank_info(struct tpm_chip *chip, u32 bank_index)
 507 {
 508         struct tpm_bank_info *bank = chip->allocated_banks + bank_index;
 509         struct tpm_digest digest = { .alg_id = bank->alg_id };
 510         int i;
 511
 512         /*
 513          * Avoid unnecessary PCR read operations to reduce overhead
 514          * and obtain identifiers of the crypto subsystem.
 515          */
 516         for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {
 517                 enum hash_algo crypto_algo = tpm2_hash_map[i].crypto_id;
 518
 519                 if (bank->alg_id != tpm2_hash_map[i].tpm_id)
 520                         continue;
 521
 522                 bank->digest_size = hash_digest_size[crypto_algo];
 523                 bank->crypto_id = crypto_algo;
 524                 return 0;
 525         }
 526
 527         return tpm2_pcr_read(chip, 0, &digest, &bank->digest_size);
 528 }
 529
 530 struct tpm2_pcr_selection {
 531         __be16  hash_alg;
 532         u8  size_of_select;
 533         u8  pcr_select[3];
 534 } __packed;
 535
 536 ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
 537 {
 538         struct tpm2_pcr_selection pcr_selection;
 539         struct tpm_buf buf;
 540         void *marker;
 541         void *end;
 542         void *pcr_select_offset;
 543         u32 sizeof_pcr_selection;
 544         u32 nr_possible_banks;
 545         u32 nr_alloc_banks = 0;
 546         u16 hash_alg;
 547         u32 rsp_len;
 548         int rc;
 549         int i = 0;
 550
 551         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
 552         if (rc)
 553                 return rc;
 554
 555         tpm_buf_append_u32(&buf, TPM2_CAP_PCRS);
 556         tpm_buf_append_u32(&buf, 0);
 557         tpm_buf_append_u32(&buf, 1);
 558
 559         rc = tpm_transmit_cmd(chip, &buf, 9, "get tpm pcr allocation");
 560         if (rc)
 561                 goto out;
 562
 563         nr_possible_banks = be32_to_cpup(
 564                 (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]);
 565
 566         chip->allocated_banks = kcalloc(nr_possible_banks,
 567                                         sizeof(*chip->allocated_banks),
 568                                         GFP_KERNEL);
 569         if (!chip->allocated_banks) {
 570                 rc = -ENOMEM;
 571                 goto out;
 572         }
 573
 574         marker = &buf.data[TPM_HEADER_SIZE + 9];
 575
 576         rsp_len = be32_to_cpup((__be32 *)&buf.data[2]);
 577         end = &buf.data[rsp_len];
 578
 579         for (i = 0; i < nr_possible_banks; i++) {
 580                 pcr_select_offset = marker +
 581                         offsetof(struct tpm2_pcr_selection, size_of_select);
 582                 if (pcr_select_offset >= end) {
 583                         rc = -EFAULT;
 584                         break;
 585                 }
 586
 587                 memcpy(&pcr_selection, marker, sizeof(pcr_selection));
 588                 hash_alg = be16_to_cpu(pcr_selection.hash_alg);
 589
 590                 pcr_select_offset = memchr_inv(pcr_selection.pcr_select, 0,
 591                                                pcr_selection.size_of_select);
 592                 if (pcr_select_offset) {
 593                         chip->allocated_banks[nr_alloc_banks].alg_id = hash_alg;
 594
 595                         rc = tpm2_init_bank_info(chip, nr_alloc_banks);
 596                         if (rc < 0)
 597                                 break;
 598
 599                         nr_alloc_banks++;
 600                 }
 601
 602                 sizeof_pcr_selection = sizeof(pcr_selection.hash_alg) +
 603                         sizeof(pcr_selection.size_of_select) +
 604                         pcr_selection.size_of_select;
 605                 marker = marker + sizeof_pcr_selection;
 606         }
 607
 608         chip->nr_allocated_banks = nr_alloc_banks;
 609 out:
 610         tpm_buf_destroy(&buf);
 611
 612         return rc;
 613 }
 614
 615 static int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
 616 {
 617         struct tpm_buf buf;
 618         u32 nr_commands;
 619         __be32 *attrs;
 620         u32 cc;
 621         int i;
 622         int rc;
 623
 624         rc = tpm2_get_tpm_pt(chip, TPM_PT_TOTAL_COMMANDS, &nr_commands, NULL);
 625         if (rc)
 626                 goto out;
 627
 628         if (nr_commands > 0xFFFFF) {
 629                 rc = -EFAULT;
 630                 goto out;
 631         }
 632
 633         chip->cc_attrs_tbl = devm_kcalloc(&chip->dev, 4, nr_commands,
 634                                           GFP_KERNEL);
 635         if (!chip->cc_attrs_tbl) {
 636                 rc = -ENOMEM;
 637                 goto out;
 638         }
 639
 640         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
 641         if (rc)
 642                 goto out;
 643
 644         tpm_buf_append_u32(&buf, TPM2_CAP_COMMANDS);
 645         tpm_buf_append_u32(&buf, TPM2_CC_FIRST);
 646         tpm_buf_append_u32(&buf, nr_commands);
 647
 648         rc = tpm_transmit_cmd(chip, &buf, 9 + 4 * nr_commands, NULL);
 649         if (rc) {
 650                 tpm_buf_destroy(&buf);
 651                 goto out;
 652         }
 653
 654         if (nr_commands !=
 655             be32_to_cpup((__be32 *)&buf.data[TPM_HEADER_SIZE + 5])) {
 656                 tpm_buf_destroy(&buf);
 657                 goto out;
 658         }
 659
 660         chip->nr_commands = nr_commands;
 661
 662         attrs = (__be32 *)&buf.data[TPM_HEADER_SIZE + 9];
 663         for (i = 0; i < nr_commands; i++, attrs++) {
 664                 chip->cc_attrs_tbl[i] = be32_to_cpup(attrs);
 665                 cc = chip->cc_attrs_tbl[i] & 0xFFFF;
 666
 667                 if (cc == TPM2_CC_CONTEXT_SAVE || cc == TPM2_CC_FLUSH_CONTEXT) {
 668                         chip->cc_attrs_tbl[i] &=
 669                                 ~(GENMASK(2, 0) << TPM2_CC_ATTR_CHANDLES);
 670                         chip->cc_attrs_tbl[i] |= 1 << TPM2_CC_ATTR_CHANDLES;
 671                 }
 672         }
 673
 674         tpm_buf_destroy(&buf);
 675
 676 out:
 677         if (rc > 0)
 678                 rc = -ENODEV;
 679         return rc;
 680 }
 681
 682 /**
 683  * tpm2_startup - turn on the TPM
 684  * @chip: TPM chip to use
 685  *
 686  * Normally the firmware should start the TPM. This function is provided as a
 687  * workaround if this does not happen. A legal case for this could be for
 688  * example when a TPM emulator is used.
 689  *
 690  * Return: same as tpm_transmit_cmd()
 691  */
 692
 693 static int tpm2_startup(struct tpm_chip *chip)
 694 {
 695         struct tpm_buf buf;
 696         int rc;
 697
 698         dev_info(&chip->dev, "starting up the TPM manually\n");
 699
 700         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_STARTUP);
 701         if (rc < 0)
 702                 return rc;
 703
 704         tpm_buf_append_u16(&buf, TPM2_SU_CLEAR);
 705         rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to start the TPM");
 706         tpm_buf_destroy(&buf);
 707
 708         return rc;
 709 }
 710
 711 /**
 712  * tpm2_auto_startup - Perform the standard automatic TPM initialization
 713  *                     sequence
 714  * @chip: TPM chip to use
 715  *
 716  * Returns 0 on success, < 0 in case of fatal error.
 717  */
 718 int tpm2_auto_startup(struct tpm_chip *chip)
 719 {
 720         int rc;
 721
 722         rc = tpm2_get_timeouts(chip);
 723         if (rc)
 724                 goto out;
 725
 726         rc = tpm2_do_selftest(chip);
 727         if (rc && rc != TPM2_RC_INITIALIZE)
 728                 goto out;
 729
 730         if (rc == TPM2_RC_INITIALIZE) {
 731                 rc = tpm2_startup(chip);
 732                 if (rc)
 733                         goto out;
 734
 735                 rc = tpm2_do_selftest(chip);
 736                 if (rc)
 737                         goto out;
 738         }
 739
 740         rc = tpm2_get_cc_attrs_tbl(chip);
 741
 742 out:
 743         if (rc > 0)
 744                 rc = -ENODEV;
 745         return rc;
 746 }
 747
 748 int tpm2_find_cc(struct tpm_chip *chip, u32 cc)
 749 {
 750         int i;
 751
 752         for (i = 0; i < chip->nr_commands; i++)
 753                 if (cc == (chip->cc_attrs_tbl[i] & GENMASK(15, 0)))
 754                         return i;
 755
 756         return -1;
 757 }