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 <[email protected]>
   7  *
   8  * Maintained by: <[email protected]>
   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 bool disable_pcr_integrity;
  18 module_param(disable_pcr_integrity, bool, 0444);
  19 MODULE_PARM_DESC(disable_pcr_integrity, "Disable integrity protection of TPM2_PCR_Extend");
  20
  21 static struct tpm2_hash tpm2_hash_map[] = {
  22         {HASH_ALGO_SHA1, TPM_ALG_SHA1},
  23         {HASH_ALGO_SHA256, TPM_ALG_SHA256},
  24         {HASH_ALGO_SHA384, TPM_ALG_SHA384},
  25         {HASH_ALGO_SHA512, TPM_ALG_SHA512},
  26         {HASH_ALGO_SM3_256, TPM_ALG_SM3_256},
  27 };
  28
  29 int tpm2_get_timeouts(struct tpm_chip *chip)
  30 {
  31         /* Fixed timeouts for TPM2 */
  32         chip->timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
  33         chip->timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
  34         chip->timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
  35         chip->timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
  36
  37         /* PTP spec timeouts */
  38         chip->duration[TPM_SHORT] = msecs_to_jiffies(TPM2_DURATION_SHORT);
  39         chip->duration[TPM_MEDIUM] = msecs_to_jiffies(TPM2_DURATION_MEDIUM);
  40         chip->duration[TPM_LONG] = msecs_to_jiffies(TPM2_DURATION_LONG);
  41
  42         /* Key creation commands long timeouts */
  43         chip->duration[TPM_LONG_LONG] =
  44                 msecs_to_jiffies(TPM2_DURATION_LONG_LONG);
  45
  46         chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
  47
  48         return 0;
  49 }
  50
  51 /**
  52  * tpm2_ordinal_duration_index() - returns an index to the chip duration table
  53  * @ordinal: TPM command ordinal.
  54  *
  55  * The function returns an index to the chip duration table
  56  * (enum tpm_duration), that describes the maximum amount of
  57  * time the chip could take to return the result for a  particular ordinal.
  58  *
  59  * The values of the MEDIUM, and LONG durations are taken
  60  * from the PC Client Profile (PTP) specification (750, 2000 msec)
  61  *
  62  * LONG_LONG is for commands that generates keys which empirically takes
  63  * a longer time on some systems.
  64  *
  65  * Return:
  66  * * TPM_MEDIUM
  67  * * TPM_LONG
  68  * * TPM_LONG_LONG
  69  * * TPM_UNDEFINED
  70  */
  71 static u8 tpm2_ordinal_duration_index(u32 ordinal)
  72 {
  73         switch (ordinal) {
  74         /* Startup */
  75         case TPM2_CC_STARTUP:                 /* 144 */
  76                 return TPM_MEDIUM;
  77
  78         case TPM2_CC_SELF_TEST:               /* 143 */
  79                 return TPM_LONG;
  80
  81         case TPM2_CC_GET_RANDOM:              /* 17B */
  82                 return TPM_LONG;
  83
  84         case TPM2_CC_SEQUENCE_UPDATE:         /* 15C */
  85                 return TPM_MEDIUM;
  86         case TPM2_CC_SEQUENCE_COMPLETE:       /* 13E */
  87                 return TPM_MEDIUM;
  88         case TPM2_CC_EVENT_SEQUENCE_COMPLETE: /* 185 */
  89                 return TPM_MEDIUM;
  90         case TPM2_CC_HASH_SEQUENCE_START:     /* 186 */
  91                 return TPM_MEDIUM;
  92
  93         case TPM2_CC_VERIFY_SIGNATURE:        /* 177 */
  94                 return TPM_LONG_LONG;
  95
  96         case TPM2_CC_PCR_EXTEND:              /* 182 */
  97                 return TPM_MEDIUM;
  98
  99         case TPM2_CC_HIERARCHY_CONTROL:       /* 121 */
 100                 return TPM_LONG;
 101         case TPM2_CC_HIERARCHY_CHANGE_AUTH:   /* 129 */
 102                 return TPM_LONG;
 103
 104         case TPM2_CC_GET_CAPABILITY:          /* 17A */
 105                 return TPM_MEDIUM;
 106
 107         case TPM2_CC_NV_READ:                 /* 14E */
 108                 return TPM_LONG;
 109
 110         case TPM2_CC_CREATE_PRIMARY:          /* 131 */
 111                 return TPM_LONG_LONG;
 112         case TPM2_CC_CREATE:                  /* 153 */
 113                 return TPM_LONG_LONG;
 114         case TPM2_CC_CREATE_LOADED:           /* 191 */
 115                 return TPM_LONG_LONG;
 116
 117         default:
 118                 return TPM_UNDEFINED;
 119         }
 120 }
 121
 122 /**
 123  * tpm2_calc_ordinal_duration() - calculate the maximum command duration
 124  * @chip:    TPM chip to use.
 125  * @ordinal: TPM command ordinal.
 126  *
 127  * The function returns the maximum amount of time the chip could take
 128  * to return the result for a particular ordinal in jiffies.
 129  *
 130  * Return: A maximal duration time for an ordinal in jiffies.
 131  */
 132 unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
 133 {
 134         unsigned int index;
 135
 136         index = tpm2_ordinal_duration_index(ordinal);
 137
 138         if (index != TPM_UNDEFINED)
 139                 return chip->duration[index];
 140         else
 141                 return msecs_to_jiffies(TPM2_DURATION_DEFAULT);
 142 }
 143
 144
 145 struct tpm2_pcr_read_out {
 146         __be32  update_cnt;
 147         __be32  pcr_selects_cnt;
 148         __be16  hash_alg;
 149         u8      pcr_select_size;
 150         u8      pcr_select[TPM2_PCR_SELECT_MIN];
 151         __be32  digests_cnt;
 152         __be16  digest_size;
 153         u8      digest[];
 154 } __packed;
 155
 156 /**
 157  * tpm2_pcr_read() - read a PCR value
 158  * @chip:       TPM chip to use.
 159  * @pcr_idx:    index of the PCR to read.
 160  * @digest:     PCR bank and buffer current PCR value is written to.
 161  * @digest_size_ptr:    pointer to variable that stores the digest size.
 162  *
 163  * Return: Same as with tpm_transmit_cmd.
 164  */
 165 int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
 166                   struct tpm_digest *digest, u16 *digest_size_ptr)
 167 {
 168         int i;
 169         int rc;
 170         struct tpm_buf buf;
 171         struct tpm2_pcr_read_out *out;
 172         u8 pcr_select[TPM2_PCR_SELECT_MIN] = {0};
 173         u16 digest_size;
 174         u16 expected_digest_size = 0;
 175
 176         if (pcr_idx >= TPM2_PLATFORM_PCR)
 177                 return -EINVAL;
 178
 179         if (!digest_size_ptr) {
 180                 for (i = 0; i < chip->nr_allocated_banks &&
 181                      chip->allocated_banks[i].alg_id != digest->alg_id; i++)
 182                         ;
 183
 184                 if (i == chip->nr_allocated_banks)
 185                         return -EINVAL;
 186
 187                 expected_digest_size = chip->allocated_banks[i].digest_size;
 188         }
 189
 190         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ);
 191         if (rc)
 192                 return rc;
 193
 194         pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
 195
 196         tpm_buf_append_u32(&buf, 1);
 197         tpm_buf_append_u16(&buf, digest->alg_id);
 198         tpm_buf_append_u8(&buf, TPM2_PCR_SELECT_MIN);
 199         tpm_buf_append(&buf, (const unsigned char *)pcr_select,
 200                        sizeof(pcr_select));
 201
 202         rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to read a pcr value");
 203         if (rc)
 204                 goto out;
 205
 206         out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE];
 207         digest_size = be16_to_cpu(out->digest_size);
 208         if (digest_size > sizeof(digest->digest) ||
 209             (!digest_size_ptr && digest_size != expected_digest_size)) {
 210                 rc = -EINVAL;
 211                 goto out;
 212         }
 213
 214         if (digest_size_ptr)
 215                 *digest_size_ptr = digest_size;
 216
 217         memcpy(digest->digest, out->digest, digest_size);
 218 out:
 219         tpm_buf_destroy(&buf);
 220         return rc;
 221 }
 222
 223 /**
 224  * tpm2_pcr_extend() - extend a PCR value
 225  *
 226  * @chip:       TPM chip to use.
 227  * @pcr_idx:    index of the PCR.
 228  * @digests:    list of pcr banks and corresponding digest values to extend.
 229  *
 230  * Return: Same as with tpm_transmit_cmd.
 231  */
 232 int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
 233                     struct tpm_digest *digests)
 234 {
 235         struct tpm_buf buf;
 236         int rc;
 237         int i;
 238
 239         if (!disable_pcr_integrity) {
 240                 rc = tpm2_start_auth_session(chip);
 241                 if (rc)
 242                         return rc;
 243         }
 244
 245         rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
 246         if (rc) {
 247                 if (!disable_pcr_integrity)
 248                         tpm2_end_auth_session(chip);
 249                 return rc;
 250         }
 251
 252         if (!disable_pcr_integrity) {
 253                 tpm_buf_append_name(chip, &buf, pcr_idx, NULL);
 254                 tpm_buf_append_hmac_session(chip, &buf, 0, NULL, 0);
 255         } else {
 256                 tpm_buf_append_handle(chip, &buf, pcr_idx);
 257                 tpm_buf_append_auth(chip, &buf, 0, NULL, 0);
 258         }
 259
 260         tpm_buf_append_u32(&buf, chip->nr_allocated_banks);
 261
 262         for (i = 0; i < chip->nr_allocated_banks; i++) {
 263                 tpm_buf_append_u16(&buf, digests[i].alg_id);
 264                 tpm_buf_append(&buf, (const unsigned char *)&digests[i].digest,
 265                                chip->allocated_banks[i].digest_size);
 266         }
 267
 268         if (!disable_pcr_integrity)
 269                 tpm_buf_fill_hmac_session(chip, &buf);
 270         rc = tpm_transmit_cmd(chip, &buf, 0, "attempting extend a PCR value");
 271         if (!disable_pcr_integrity)
 272                 rc = tpm_buf_check_hmac_response(chip, &buf, rc);
 273
 274         tpm_buf_destroy(&buf);
 275
 276         return rc;
 277 }
 278
 279 struct tpm2_get_random_out {
 280         __be16 size;
 281         u8 buffer[TPM_MAX_RNG_DATA];
 282 } __packed;
 283
 284 /**
 285  * tpm2_get_random() - get random bytes from the TPM RNG
 286  *
 287  * @chip:       a &tpm_chip instance
 288  * @dest:       destination buffer
 289  * @max:        the max number of random bytes to pull
 290  *
 291  * Return:
 292  *   size of the buffer on success,
 293  *   -errno otherwise (positive TPM return codes are masked to -EIO)
 294  */
 295 int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
 296 {
 297         struct tpm2_get_random_out *out;
 298         struct tpm_header *head;
 299         struct tpm_buf buf;
 300         u32 recd;
 301         u32 num_bytes = max;
 302         int err;
 303         int total = 0;
 304         int retries = 5;
 305         u8 *dest_ptr = dest;
 306         off_t offset;
 307
 308         if (!num_bytes || max > TPM_MAX_RNG_DATA)
 309                 return -EINVAL;
 310
 311         err = tpm2_start_auth_session(chip);
 312         if (err)
 313                 return err;
 314
 315         err = tpm_buf_init(&buf, 0, 0);
 316         if (err) {
 317                 tpm2_end_auth_session(chip);
 318                 return err;
 319         }
 320
 321         do {
 322                 tpm_buf_reset(&buf, TPM2_ST_SESSIONS, TPM2_CC_GET_RANDOM);
 323                 tpm_buf_append_hmac_session_opt(chip, &buf, TPM2_SA_ENCRYPT
 324                                                 | TPM2_SA_CONTINUE_SESSION,
 325                                                 NULL, 0);
 326                 tpm_buf_append_u16(&buf, num_bytes);
 327                 tpm_buf_fill_hmac_session(chip, &buf);
 328                 err = tpm_transmit_cmd(chip, &buf,
 329                                        offsetof(struct tpm2_get_random_out,
 330                                                 buffer),
 331                                        "attempting get random");
 332                 err = tpm_buf_check_hmac_response(chip, &buf, err);
 333                 if (err) {
 334                         if (err > 0)
 335                                 err = -EIO;
 336                         goto out;
 337                 }
 338
 339                 head = (struct tpm_header *)buf.data;
 340                 offset = TPM_HEADER_SIZE;
 341                 /* Skip the parameter size field: */
 342                 if (be16_to_cpu(head->tag) == TPM2_ST_SESSIONS)
 343                         offset += 4;
 344
 345                 out = (struct tpm2_get_random_out *)&buf.data[offset];
 346                 recd = min_t(u32, be16_to_cpu(out->size), num_bytes);
 347                 if (tpm_buf_length(&buf) <
 348                     TPM_HEADER_SIZE +
 349                     offsetof(struct tpm2_get_random_out, buffer) +
 350                     recd) {
 351                         err = -EFAULT;
 352                         goto out;
 353                 }
 354                 memcpy(dest_ptr, out->buffer, recd);
 355
 356                 dest_ptr += recd;
 357                 total += recd;
 358                 num_bytes -= recd;
 359         } while (retries-- && total < max);
 360
 361         tpm_buf_destroy(&buf);
 362         tpm2_end_auth_session(chip);
 363
 364         return total ? total : -EIO;
 365 out:
 366         tpm_buf_destroy(&buf);
 367         tpm2_end_auth_session(chip);
 368         return err;
 369 }
 370
 371 /**
 372  * tpm2_flush_context() - execute a TPM2_FlushContext command
 373  * @chip:       TPM chip to use
 374  * @handle:     context handle
 375  */
 376 void tpm2_flush_context(struct tpm_chip *chip, u32 handle)
 377 {
 378         struct tpm_buf buf;
 379         int rc;
 380
 381         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
 382         if (rc) {
 383                 dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n",
 384                          handle);
 385                 return;
 386         }
 387
 388         tpm_buf_append_u32(&buf, handle);
 389
 390         tpm_transmit_cmd(chip, &buf, 0, "flushing context");
 391         tpm_buf_destroy(&buf);
 392 }
 393 EXPORT_SYMBOL_GPL(tpm2_flush_context);
 394
 395 struct tpm2_get_cap_out {
 396         u8 more_data;
 397         __be32 subcap_id;
 398         __be32 property_cnt;
 399         __be32 property_id;
 400         __be32 value;
 401 } __packed;
 402
 403 /**
 404  * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
 405  * @chip:               a &tpm_chip instance
 406  * @property_id:        property ID.
 407  * @value:              output variable.
 408  * @desc:               passed to tpm_transmit_cmd()
 409  *
 410  * Return:
 411  *   0 on success,
 412  *   -errno or a TPM return code otherwise
 413  */
 414 ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
 415                         const char *desc)
 416 {
 417         struct tpm2_get_cap_out *out;
 418         struct tpm_buf buf;
 419         int rc;
 420
 421         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
 422         if (rc)
 423                 return rc;
 424         tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
 425         tpm_buf_append_u32(&buf, property_id);
 426         tpm_buf_append_u32(&buf, 1);
 427         rc = tpm_transmit_cmd(chip, &buf, 0, NULL);
 428         if (!rc) {
 429                 out = (struct tpm2_get_cap_out *)
 430                         &buf.data[TPM_HEADER_SIZE];
 431                 /*
 432                  * To prevent failing boot up of some systems, Infineon TPM2.0
 433                  * returns SUCCESS on TPM2_Startup in field upgrade mode. Also
 434                  * the TPM2_Getcapability command returns a zero length list
 435                  * in field upgrade mode.
 436                  */
 437                 if (be32_to_cpu(out->property_cnt) > 0)
 438                         *value = be32_to_cpu(out->value);
 439                 else
 440                         rc = -ENODATA;
 441         }
 442         tpm_buf_destroy(&buf);
 443         return rc;
 444 }
 445 EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
 446
 447 /**
 448  * tpm2_shutdown() - send a TPM shutdown command
 449  *
 450  * Sends a TPM shutdown command. The shutdown command is used in call
 451  * sites where the system is going down. If it fails, there is not much
 452  * that can be done except print an error message.
 453  *
 454  * @chip:               a &tpm_chip instance
 455  * @shutdown_type:      TPM_SU_CLEAR or TPM_SU_STATE.
 456  */
 457 void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
 458 {
 459         struct tpm_buf buf;
 460         int rc;
 461
 462         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SHUTDOWN);
 463         if (rc)
 464                 return;
 465         tpm_buf_append_u16(&buf, shutdown_type);
 466         tpm_transmit_cmd(chip, &buf, 0, "stopping the TPM");
 467         tpm_buf_destroy(&buf);
 468 }
 469
 470 /**
 471  * tpm2_do_selftest() - ensure that all self tests have passed
 472  *
 473  * @chip: TPM chip to use
 474  *
 475  * Return: Same as with tpm_transmit_cmd.
 476  *
 477  * The TPM can either run all self tests synchronously and then return
 478  * RC_SUCCESS once all tests were successful. Or it can choose to run the tests
 479  * asynchronously and return RC_TESTING immediately while the self tests still
 480  * execute in the background. This function handles both cases and waits until
 481  * all tests have completed.
 482  */
 483 static int tpm2_do_selftest(struct tpm_chip *chip)
 484 {
 485         struct tpm_buf buf;
 486         int full;
 487         int rc;
 488
 489         for (full = 0; full < 2; full++) {
 490                 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SELF_TEST);
 491                 if (rc)
 492                         return rc;
 493
 494                 tpm_buf_append_u8(&buf, full);
 495                 rc = tpm_transmit_cmd(chip, &buf, 0,
 496                                       "attempting the self test");
 497                 tpm_buf_destroy(&buf);
 498
 499                 if (rc == TPM2_RC_TESTING)
 500                         rc = TPM2_RC_SUCCESS;
 501                 if (rc == TPM2_RC_INITIALIZE || rc == TPM2_RC_SUCCESS)
 502                         return rc;
 503         }
 504
 505         return rc;
 506 }
 507
 508 /**
 509  * tpm2_probe() - probe for the TPM 2.0 protocol
 510  * @chip:       a &tpm_chip instance
 511  *
 512  * Send an idempotent TPM 2.0 command and see whether there is TPM2 chip in the
 513  * other end based on the response tag. The flag TPM_CHIP_FLAG_TPM2 is set by
 514  * this function if this is the case.
 515  *
 516  * Return:
 517  *   0 on success,
 518  *   -errno otherwise
 519  */
 520 int tpm2_probe(struct tpm_chip *chip)
 521 {
 522         struct tpm_header *out;
 523         struct tpm_buf buf;
 524         int rc;
 525
 526         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
 527         if (rc)
 528                 return rc;
 529         tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
 530         tpm_buf_append_u32(&buf, TPM_PT_TOTAL_COMMANDS);
 531         tpm_buf_append_u32(&buf, 1);
 532         rc = tpm_transmit_cmd(chip, &buf, 0, NULL);
 533         /* We ignore TPM return codes on purpose. */
 534         if (rc >=  0) {
 535                 out = (struct tpm_header *)buf.data;
 536                 if (be16_to_cpu(out->tag) == TPM2_ST_NO_SESSIONS)
 537                         chip->flags |= TPM_CHIP_FLAG_TPM2;
 538         }
 539         tpm_buf_destroy(&buf);
 540         return 0;
 541 }
 542 EXPORT_SYMBOL_GPL(tpm2_probe);
 543
 544 static int tpm2_init_bank_info(struct tpm_chip *chip, u32 bank_index)
 545 {
 546         struct tpm_bank_info *bank = chip->allocated_banks + bank_index;
 547         struct tpm_digest digest = { .alg_id = bank->alg_id };
 548         int i;
 549
 550         /*
 551          * Avoid unnecessary PCR read operations to reduce overhead
 552          * and obtain identifiers of the crypto subsystem.
 553          */
 554         for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {
 555                 enum hash_algo crypto_algo = tpm2_hash_map[i].crypto_id;
 556
 557                 if (bank->alg_id != tpm2_hash_map[i].tpm_id)
 558                         continue;
 559
 560                 bank->digest_size = hash_digest_size[crypto_algo];
 561                 bank->crypto_id = crypto_algo;
 562                 return 0;
 563         }
 564
 565         bank->crypto_id = HASH_ALGO__LAST;
 566
 567         return tpm2_pcr_read(chip, 0, &digest, &bank->digest_size);
 568 }
 569
 570 struct tpm2_pcr_selection {
 571         __be16  hash_alg;
 572         u8  size_of_select;
 573         u8  pcr_select[3];
 574 } __packed;
 575
 576 ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
 577 {
 578         struct tpm2_pcr_selection pcr_selection;
 579         struct tpm_buf buf;
 580         void *marker;
 581         void *end;
 582         void *pcr_select_offset;
 583         u32 sizeof_pcr_selection;
 584         u32 nr_possible_banks;
 585         u32 nr_alloc_banks = 0;
 586         u16 hash_alg;
 587         u32 rsp_len;
 588         int rc;
 589         int i = 0;
 590
 591         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
 592         if (rc)
 593                 return rc;
 594
 595         tpm_buf_append_u32(&buf, TPM2_CAP_PCRS);
 596         tpm_buf_append_u32(&buf, 0);
 597         tpm_buf_append_u32(&buf, 1);
 598
 599         rc = tpm_transmit_cmd(chip, &buf, 9, "get tpm pcr allocation");
 600         if (rc)
 601                 goto out;
 602
 603         nr_possible_banks = be32_to_cpup(
 604                 (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]);
 605
 606         chip->allocated_banks = kcalloc(nr_possible_banks,
 607                                         sizeof(*chip->allocated_banks),
 608                                         GFP_KERNEL);
 609         if (!chip->allocated_banks) {
 610                 rc = -ENOMEM;
 611                 goto out;
 612         }
 613
 614         marker = &buf.data[TPM_HEADER_SIZE + 9];
 615
 616         rsp_len = be32_to_cpup((__be32 *)&buf.data[2]);
 617         end = &buf.data[rsp_len];
 618
 619         for (i = 0; i < nr_possible_banks; i++) {
 620                 pcr_select_offset = marker +
 621                         offsetof(struct tpm2_pcr_selection, size_of_select);
 622                 if (pcr_select_offset >= end) {
 623                         rc = -EFAULT;
 624                         break;
 625                 }
 626
 627                 memcpy(&pcr_selection, marker, sizeof(pcr_selection));
 628                 hash_alg = be16_to_cpu(pcr_selection.hash_alg);
 629
 630                 pcr_select_offset = memchr_inv(pcr_selection.pcr_select, 0,
 631                                                pcr_selection.size_of_select);
 632                 if (pcr_select_offset) {
 633                         chip->allocated_banks[nr_alloc_banks].alg_id = hash_alg;
 634
 635                         rc = tpm2_init_bank_info(chip, nr_alloc_banks);
 636                         if (rc < 0)
 637                                 break;
 638
 639                         nr_alloc_banks++;
 640                 }
 641
 642                 sizeof_pcr_selection = sizeof(pcr_selection.hash_alg) +
 643                         sizeof(pcr_selection.size_of_select) +
 644                         pcr_selection.size_of_select;
 645                 marker = marker + sizeof_pcr_selection;
 646         }
 647
 648         chip->nr_allocated_banks = nr_alloc_banks;
 649 out:
 650         tpm_buf_destroy(&buf);
 651
 652         return rc;
 653 }
 654
 655 int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
 656 {
 657         struct tpm_buf buf;
 658         u32 nr_commands;
 659         __be32 *attrs;
 660         u32 cc;
 661         int i;
 662         int rc;
 663
 664         rc = tpm2_get_tpm_pt(chip, TPM_PT_TOTAL_COMMANDS, &nr_commands, NULL);
 665         if (rc)
 666                 goto out;
 667
 668         if (nr_commands > 0xFFFFF) {
 669                 rc = -EFAULT;
 670                 goto out;
 671         }
 672
 673         chip->cc_attrs_tbl = devm_kcalloc(&chip->dev, 4, nr_commands,
 674                                           GFP_KERNEL);
 675         if (!chip->cc_attrs_tbl) {
 676                 rc = -ENOMEM;
 677                 goto out;
 678         }
 679
 680         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
 681         if (rc)
 682                 goto out;
 683
 684         tpm_buf_append_u32(&buf, TPM2_CAP_COMMANDS);
 685         tpm_buf_append_u32(&buf, TPM2_CC_FIRST);
 686         tpm_buf_append_u32(&buf, nr_commands);
 687
 688         rc = tpm_transmit_cmd(chip, &buf, 9 + 4 * nr_commands, NULL);
 689         if (rc) {
 690                 tpm_buf_destroy(&buf);
 691                 goto out;
 692         }
 693
 694         if (nr_commands !=
 695             be32_to_cpup((__be32 *)&buf.data[TPM_HEADER_SIZE + 5])) {
 696                 rc = -EFAULT;
 697                 tpm_buf_destroy(&buf);
 698                 goto out;
 699         }
 700
 701         chip->nr_commands = nr_commands;
 702
 703         attrs = (__be32 *)&buf.data[TPM_HEADER_SIZE + 9];
 704         for (i = 0; i < nr_commands; i++, attrs++) {
 705                 chip->cc_attrs_tbl[i] = be32_to_cpup(attrs);
 706                 cc = chip->cc_attrs_tbl[i] & 0xFFFF;
 707
 708                 if (cc == TPM2_CC_CONTEXT_SAVE || cc == TPM2_CC_FLUSH_CONTEXT) {
 709                         chip->cc_attrs_tbl[i] &=
 710                                 ~(GENMASK(2, 0) << TPM2_CC_ATTR_CHANDLES);
 711                         chip->cc_attrs_tbl[i] |= 1 << TPM2_CC_ATTR_CHANDLES;
 712                 }
 713         }
 714
 715         tpm_buf_destroy(&buf);
 716
 717 out:
 718         if (rc > 0)
 719                 rc = -ENODEV;
 720         return rc;
 721 }
 722 EXPORT_SYMBOL_GPL(tpm2_get_cc_attrs_tbl);
 723
 724 /**
 725  * tpm2_startup - turn on the TPM
 726  * @chip: TPM chip to use
 727  *
 728  * Normally the firmware should start the TPM. This function is provided as a
 729  * workaround if this does not happen. A legal case for this could be for
 730  * example when a TPM emulator is used.
 731  *
 732  * Return: same as tpm_transmit_cmd()
 733  */
 734
 735 static int tpm2_startup(struct tpm_chip *chip)
 736 {
 737         struct tpm_buf buf;
 738         int rc;
 739
 740         dev_info(&chip->dev, "starting up the TPM manually\n");
 741
 742         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_STARTUP);
 743         if (rc < 0)
 744                 return rc;
 745
 746         tpm_buf_append_u16(&buf, TPM2_SU_CLEAR);
 747         rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to start the TPM");
 748         tpm_buf_destroy(&buf);
 749
 750         return rc;
 751 }
 752
 753 /**
 754  * tpm2_auto_startup - Perform the standard automatic TPM initialization
 755  *                     sequence
 756  * @chip: TPM chip to use
 757  *
 758  * Returns 0 on success, < 0 in case of fatal error.
 759  */
 760 int tpm2_auto_startup(struct tpm_chip *chip)
 761 {
 762         int rc;
 763
 764         rc = tpm2_get_timeouts(chip);
 765         if (rc)
 766                 goto out;
 767
 768         rc = tpm2_do_selftest(chip);
 769         if (rc && rc != TPM2_RC_INITIALIZE)
 770                 goto out;
 771
 772         if (rc == TPM2_RC_INITIALIZE) {
 773                 rc = tpm2_startup(chip);
 774                 if (rc)
 775                         goto out;
 776
 777                 rc = tpm2_do_selftest(chip);
 778                 if (rc)
 779                         goto out;
 780         }
 781
 782         rc = tpm2_get_cc_attrs_tbl(chip);
 783         if (rc == TPM2_RC_FAILURE || (rc < 0 && rc != -ENOMEM)) {
 784                 dev_info(&chip->dev,
 785                          "TPM in field failure mode, requires firmware upgrade\n");
 786                 chip->flags |= TPM_CHIP_FLAG_FIRMWARE_UPGRADE;
 787                 rc = 0;
 788         }
 789
 790         if (rc)
 791                 goto out;
 792
 793         rc = tpm2_sessions_init(chip);
 794
 795 out:
 796         /*
 797          * Infineon TPM in field upgrade mode will return no data for the number
 798          * of supported commands.
 799          */
 800         if (rc == TPM2_RC_UPGRADE || rc == -ENODATA) {
 801                 dev_info(&chip->dev, "TPM in field upgrade mode, requires firmware upgrade\n");
 802                 chip->flags |= TPM_CHIP_FLAG_FIRMWARE_UPGRADE;
 803                 rc = 0;
 804         }
 805
 806         if (rc > 0)
 807                 rc = -ENODEV;
 808         return rc;
 809 }
 810
 811 int tpm2_find_cc(struct tpm_chip *chip, u32 cc)
 812 {
 813         u32 cc_mask;
 814         int i;
 815
 816         cc_mask = 1 << TPM2_CC_ATTR_VENDOR | GENMASK(15, 0);
 817         for (i = 0; i < chip->nr_commands; i++)
 818                 if (cc == (chip->cc_attrs_tbl[i] & cc_mask))
 819                         return i;
 820
 821         return -1;
 822 }