drivers/char/tpm/tpm-interface.c

   1 /*
   2  * Copyright (C) 2004 IBM Corporation
   3  * Copyright (C) 2014 Intel Corporation
   4  *
   5  * Authors:
   6  * Leendert van Doorn <leendert@watson.ibm.com>
   7  * Dave Safford <safford@watson.ibm.com>
   8  * Reiner Sailer <sailer@watson.ibm.com>
   9  * Kylene Hall <kjhall@us.ibm.com>
  10  *
  11  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
  12  *
  13  * Device driver for TCG/TCPA TPM (trusted platform module).
  14  * Specifications at www.trustedcomputinggroup.org
  15  *
  16  * This program is free software; you can redistribute it and/or
  17  * modify it under the terms of the GNU General Public License as
  18  * published by the Free Software Foundation, version 2 of the
  19  * License.
  20  *
  21  * Note, the TPM chip is not interrupt driven (only polling)
  22  * and can have very long timeouts (minutes!). Hence the unusual
  23  * calls to msleep.
  24  *
  25  */
  26
  27 #include <linux/poll.h>
  28 #include <linux/slab.h>
  29 #include <linux/mutex.h>
  30 #include <linux/spinlock.h>
  31 #include <linux/freezer.h>
  32 #include <linux/pm_runtime.h>
  33 #include <linux/tpm_eventlog.h>
  34
  35 #include "tpm.h"
  36
  37 #define TPM_MAX_ORDINAL 243
  38 #define TSC_MAX_ORDINAL 12
  39 #define TPM_PROTECTED_COMMAND 0x00
  40 #define TPM_CONNECTION_COMMAND 0x40
  41
  42 /*
  43  * Bug workaround - some TPM's don't flush the most
  44  * recently changed pcr on suspend, so force the flush
  45  * with an extend to the selected _unused_ non-volatile pcr.
  46  */
  47 static int tpm_suspend_pcr;
  48 module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644);
  49 MODULE_PARM_DESC(suspend_pcr,
  50                  "PCR to use for dummy writes to facilitate flush on suspend.");
  51
  52 /*
  53  * Array with one entry per ordinal defining the maximum amount
  54  * of time the chip could take to return the result.  The ordinal
  55  * designation of short, medium or long is defined in a table in
  56  * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
  57  * values of the SHORT, MEDIUM, and LONG durations are retrieved
  58  * from the chip during initialization with a call to tpm_get_timeouts.
  59  */
  60 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
  61         TPM_UNDEFINED,          /* 0 */
  62         TPM_UNDEFINED,
  63         TPM_UNDEFINED,
  64         TPM_UNDEFINED,
  65         TPM_UNDEFINED,
  66         TPM_UNDEFINED,          /* 5 */
  67         TPM_UNDEFINED,
  68         TPM_UNDEFINED,
  69         TPM_UNDEFINED,
  70         TPM_UNDEFINED,
  71         TPM_SHORT,              /* 10 */
  72         TPM_SHORT,
  73         TPM_MEDIUM,
  74         TPM_LONG,
  75         TPM_LONG,
  76         TPM_MEDIUM,             /* 15 */
  77         TPM_SHORT,
  78         TPM_SHORT,
  79         TPM_MEDIUM,
  80         TPM_LONG,
  81         TPM_SHORT,              /* 20 */
  82         TPM_SHORT,
  83         TPM_MEDIUM,
  84         TPM_MEDIUM,
  85         TPM_MEDIUM,
  86         TPM_SHORT,              /* 25 */
  87         TPM_SHORT,
  88         TPM_MEDIUM,
  89         TPM_SHORT,
  90         TPM_SHORT,
  91         TPM_MEDIUM,             /* 30 */
  92         TPM_LONG,
  93         TPM_MEDIUM,
  94         TPM_SHORT,
  95         TPM_SHORT,
  96         TPM_SHORT,              /* 35 */
  97         TPM_MEDIUM,
  98         TPM_MEDIUM,
  99         TPM_UNDEFINED,
 100         TPM_UNDEFINED,
 101         TPM_MEDIUM,             /* 40 */
 102         TPM_LONG,
 103         TPM_MEDIUM,
 104         TPM_SHORT,
 105         TPM_SHORT,
 106         TPM_SHORT,              /* 45 */
 107         TPM_SHORT,
 108         TPM_SHORT,
 109         TPM_SHORT,
 110         TPM_LONG,
 111         TPM_MEDIUM,             /* 50 */
 112         TPM_MEDIUM,
 113         TPM_UNDEFINED,
 114         TPM_UNDEFINED,
 115         TPM_UNDEFINED,
 116         TPM_UNDEFINED,          /* 55 */
 117         TPM_UNDEFINED,
 118         TPM_UNDEFINED,
 119         TPM_UNDEFINED,
 120         TPM_UNDEFINED,
 121         TPM_MEDIUM,             /* 60 */
 122         TPM_MEDIUM,
 123         TPM_MEDIUM,
 124         TPM_SHORT,
 125         TPM_SHORT,
 126         TPM_MEDIUM,             /* 65 */
 127         TPM_UNDEFINED,
 128         TPM_UNDEFINED,
 129         TPM_UNDEFINED,
 130         TPM_UNDEFINED,
 131         TPM_SHORT,              /* 70 */
 132         TPM_SHORT,
 133         TPM_UNDEFINED,
 134         TPM_UNDEFINED,
 135         TPM_UNDEFINED,
 136         TPM_UNDEFINED,          /* 75 */
 137         TPM_UNDEFINED,
 138         TPM_UNDEFINED,
 139         TPM_UNDEFINED,
 140         TPM_UNDEFINED,
 141         TPM_LONG,               /* 80 */
 142         TPM_UNDEFINED,
 143         TPM_MEDIUM,
 144         TPM_LONG,
 145         TPM_SHORT,
 146         TPM_UNDEFINED,          /* 85 */
 147         TPM_UNDEFINED,
 148         TPM_UNDEFINED,
 149         TPM_UNDEFINED,
 150         TPM_UNDEFINED,
 151         TPM_SHORT,              /* 90 */
 152         TPM_SHORT,
 153         TPM_SHORT,
 154         TPM_SHORT,
 155         TPM_SHORT,
 156         TPM_UNDEFINED,          /* 95 */
 157         TPM_UNDEFINED,
 158         TPM_UNDEFINED,
 159         TPM_UNDEFINED,
 160         TPM_UNDEFINED,
 161         TPM_MEDIUM,             /* 100 */
 162         TPM_SHORT,
 163         TPM_SHORT,
 164         TPM_UNDEFINED,
 165         TPM_UNDEFINED,
 166         TPM_UNDEFINED,          /* 105 */
 167         TPM_UNDEFINED,
 168         TPM_UNDEFINED,
 169         TPM_UNDEFINED,
 170         TPM_UNDEFINED,
 171         TPM_SHORT,              /* 110 */
 172         TPM_SHORT,
 173         TPM_SHORT,
 174         TPM_SHORT,
 175         TPM_SHORT,
 176         TPM_SHORT,              /* 115 */
 177         TPM_SHORT,
 178         TPM_SHORT,
 179         TPM_UNDEFINED,
 180         TPM_UNDEFINED,
 181         TPM_LONG,               /* 120 */
 182         TPM_LONG,
 183         TPM_MEDIUM,
 184         TPM_UNDEFINED,
 185         TPM_SHORT,
 186         TPM_SHORT,              /* 125 */
 187         TPM_SHORT,
 188         TPM_LONG,
 189         TPM_SHORT,
 190         TPM_SHORT,
 191         TPM_SHORT,              /* 130 */
 192         TPM_MEDIUM,
 193         TPM_UNDEFINED,
 194         TPM_SHORT,
 195         TPM_MEDIUM,
 196         TPM_UNDEFINED,          /* 135 */
 197         TPM_UNDEFINED,
 198         TPM_UNDEFINED,
 199         TPM_UNDEFINED,
 200         TPM_UNDEFINED,
 201         TPM_SHORT,              /* 140 */
 202         TPM_SHORT,
 203         TPM_UNDEFINED,
 204         TPM_UNDEFINED,
 205         TPM_UNDEFINED,
 206         TPM_UNDEFINED,          /* 145 */
 207         TPM_UNDEFINED,
 208         TPM_UNDEFINED,
 209         TPM_UNDEFINED,
 210         TPM_UNDEFINED,
 211         TPM_SHORT,              /* 150 */
 212         TPM_MEDIUM,
 213         TPM_MEDIUM,
 214         TPM_SHORT,
 215         TPM_SHORT,
 216         TPM_UNDEFINED,          /* 155 */
 217         TPM_UNDEFINED,
 218         TPM_UNDEFINED,
 219         TPM_UNDEFINED,
 220         TPM_UNDEFINED,
 221         TPM_SHORT,              /* 160 */
 222         TPM_SHORT,
 223         TPM_SHORT,
 224         TPM_SHORT,
 225         TPM_UNDEFINED,
 226         TPM_UNDEFINED,          /* 165 */
 227         TPM_UNDEFINED,
 228         TPM_UNDEFINED,
 229         TPM_UNDEFINED,
 230         TPM_UNDEFINED,
 231         TPM_LONG,               /* 170 */
 232         TPM_UNDEFINED,
 233         TPM_UNDEFINED,
 234         TPM_UNDEFINED,
 235         TPM_UNDEFINED,
 236         TPM_UNDEFINED,          /* 175 */
 237         TPM_UNDEFINED,
 238         TPM_UNDEFINED,
 239         TPM_UNDEFINED,
 240         TPM_UNDEFINED,
 241         TPM_MEDIUM,             /* 180 */
 242         TPM_SHORT,
 243         TPM_MEDIUM,
 244         TPM_MEDIUM,
 245         TPM_MEDIUM,
 246         TPM_MEDIUM,             /* 185 */
 247         TPM_SHORT,
 248         TPM_UNDEFINED,
 249         TPM_UNDEFINED,
 250         TPM_UNDEFINED,
 251         TPM_UNDEFINED,          /* 190 */
 252         TPM_UNDEFINED,
 253         TPM_UNDEFINED,
 254         TPM_UNDEFINED,
 255         TPM_UNDEFINED,
 256         TPM_UNDEFINED,          /* 195 */
 257         TPM_UNDEFINED,
 258         TPM_UNDEFINED,
 259         TPM_UNDEFINED,
 260         TPM_UNDEFINED,
 261         TPM_SHORT,              /* 200 */
 262         TPM_UNDEFINED,
 263         TPM_UNDEFINED,
 264         TPM_UNDEFINED,
 265         TPM_SHORT,
 266         TPM_SHORT,              /* 205 */
 267         TPM_SHORT,
 268         TPM_SHORT,
 269         TPM_SHORT,
 270         TPM_SHORT,
 271         TPM_MEDIUM,             /* 210 */
 272         TPM_UNDEFINED,
 273         TPM_MEDIUM,
 274         TPM_MEDIUM,
 275         TPM_MEDIUM,
 276         TPM_UNDEFINED,          /* 215 */
 277         TPM_MEDIUM,
 278         TPM_UNDEFINED,
 279         TPM_UNDEFINED,
 280         TPM_SHORT,
 281         TPM_SHORT,              /* 220 */
 282         TPM_SHORT,
 283         TPM_SHORT,
 284         TPM_SHORT,
 285         TPM_SHORT,
 286         TPM_UNDEFINED,          /* 225 */
 287         TPM_UNDEFINED,
 288         TPM_UNDEFINED,
 289         TPM_UNDEFINED,
 290         TPM_UNDEFINED,
 291         TPM_SHORT,              /* 230 */
 292         TPM_LONG,
 293         TPM_MEDIUM,
 294         TPM_UNDEFINED,
 295         TPM_UNDEFINED,
 296         TPM_UNDEFINED,          /* 235 */
 297         TPM_UNDEFINED,
 298         TPM_UNDEFINED,
 299         TPM_UNDEFINED,
 300         TPM_UNDEFINED,
 301         TPM_SHORT,              /* 240 */
 302         TPM_UNDEFINED,
 303         TPM_MEDIUM,
 304 };
 305
 306 /*
 307  * Returns max number of jiffies to wait
 308  */
 309 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
 310                                            u32 ordinal)
 311 {
 312         int duration_idx = TPM_UNDEFINED;
 313         int duration = 0;
 314
 315         /*
 316          * We only have a duration table for protected commands, where the upper
 317          * 16 bits are 0. For the few other ordinals the fallback will be used.
 318          */
 319         if (ordinal < TPM_MAX_ORDINAL)
 320                 duration_idx = tpm_ordinal_duration[ordinal];
 321
 322         if (duration_idx != TPM_UNDEFINED)
 323                 duration = chip->duration[duration_idx];
 324         if (duration <= 0)
 325                 return 2 * 60 * HZ;
 326         else
 327                 return duration;
 328 }
 329 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 330
 331 static int tpm_validate_command(struct tpm_chip *chip,
 332                                  struct tpm_space *space,
 333                                  const u8 *cmd,
 334                                  size_t len)
 335 {
 336         const struct tpm_input_header *header = (const void *)cmd;
 337         int i;
 338         u32 cc;
 339         u32 attrs;
 340         unsigned int nr_handles;
 341
 342         if (len < TPM_HEADER_SIZE)
 343                 return -EINVAL;
 344
 345         if (!space)
 346                 return 0;
 347
 348         if (chip->flags & TPM_CHIP_FLAG_TPM2 && chip->nr_commands) {
 349                 cc = be32_to_cpu(header->ordinal);
 350
 351                 i = tpm2_find_cc(chip, cc);
 352                 if (i < 0) {
 353                         dev_dbg(&chip->dev, "0x%04X is an invalid command\n",
 354                                 cc);
 355                         return -EOPNOTSUPP;
 356                 }
 357
 358                 attrs = chip->cc_attrs_tbl[i];
 359                 nr_handles =
 360                         4 * ((attrs >> TPM2_CC_ATTR_CHANDLES) & GENMASK(2, 0));
 361                 if (len < TPM_HEADER_SIZE + 4 * nr_handles)
 362                         goto err_len;
 363         }
 364
 365         return 0;
 366 err_len:
 367         dev_dbg(&chip->dev,
 368                 "%s: insufficient command length %zu", __func__, len);
 369         return -EINVAL;
 370 }
 371
 372 /**
 373  * tmp_transmit - Internal kernel interface to transmit TPM commands.
 374  *
 375  * @chip: TPM chip to use
 376  * @buf: TPM command buffer
 377  * @bufsiz: length of the TPM command buffer
 378  * @flags: tpm transmit flags - bitmap
 379  *
 380  * Return:
 381  *     0 when the operation is successful.
 382  *     A negative number for system errors (errno).
 383  */
 384 ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
 385                      u8 *buf, size_t bufsiz, unsigned int flags)
 386 {
 387         struct tpm_output_header *header = (void *)buf;
 388         int rc;
 389         ssize_t len = 0;
 390         u32 count, ordinal;
 391         unsigned long stop;
 392         bool need_locality;
 393
 394         rc = tpm_validate_command(chip, space, buf, bufsiz);
 395         if (rc == -EINVAL)
 396                 return rc;
 397         /*
 398          * If the command is not implemented by the TPM, synthesize a
 399          * response with a TPM2_RC_COMMAND_CODE return for user-space.
 400          */
 401         if (rc == -EOPNOTSUPP) {
 402                 header->length = cpu_to_be32(sizeof(*header));
 403                 header->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
 404                 header->return_code = cpu_to_be32(TPM2_RC_COMMAND_CODE |
 405                                                   TSS2_RESMGR_TPM_RC_LAYER);
 406                 return bufsiz;
 407         }
 408
 409         if (bufsiz > TPM_BUFSIZE)
 410                 bufsiz = TPM_BUFSIZE;
 411
 412         count = be32_to_cpu(*((__be32 *) (buf + 2)));
 413         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
 414         if (count == 0)
 415                 return -ENODATA;
 416         if (count > bufsiz) {
 417                 dev_err(&chip->dev,
 418                         "invalid count value %x %zx\n", count, bufsiz);
 419                 return -E2BIG;
 420         }
 421
 422         if (!(flags & TPM_TRANSMIT_UNLOCKED))
 423                 mutex_lock(&chip->tpm_mutex);
 424
 425         if (chip->dev.parent)
 426                 pm_runtime_get_sync(chip->dev.parent);
 427
 428         if (chip->ops->clk_enable != NULL)
 429                 chip->ops->clk_enable(chip, true);
 430
 431         /* Store the decision as chip->locality will be changed. */
 432         need_locality = chip->locality == -1;
 433
 434         if (!(flags & TPM_TRANSMIT_RAW) &&
 435             need_locality && chip->ops->request_locality)  {
 436                 rc = chip->ops->request_locality(chip, 0);
 437                 if (rc < 0)
 438                         goto out_no_locality;
 439                 chip->locality = rc;
 440         }
 441
 442         rc = tpm2_prepare_space(chip, space, ordinal, buf);
 443         if (rc)
 444                 goto out;
 445
 446         rc = chip->ops->send(chip, (u8 *) buf, count);
 447         if (rc < 0) {
 448                 if (rc != -EPIPE)
 449                         dev_err(&chip->dev,
 450                                 "%s: tpm_send: error %d\n", __func__, rc);
 451                 goto out;
 452         }
 453
 454         if (chip->flags & TPM_CHIP_FLAG_IRQ)
 455                 goto out_recv;
 456
 457         if (chip->flags & TPM_CHIP_FLAG_TPM2)
 458                 stop = jiffies + tpm2_calc_ordinal_duration(chip, ordinal);
 459         else
 460                 stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
 461         do {
 462                 u8 status = chip->ops->status(chip);
 463                 if ((status & chip->ops->req_complete_mask) ==
 464                     chip->ops->req_complete_val)
 465                         goto out_recv;
 466
 467                 if (chip->ops->req_canceled(chip, status)) {
 468                         dev_err(&chip->dev, "Operation Canceled\n");
 469                         rc = -ECANCELED;
 470                         goto out;
 471                 }
 472
 473                 tpm_msleep(TPM_TIMEOUT);
 474                 rmb();
 475         } while (time_before(jiffies, stop));
 476
 477         chip->ops->cancel(chip);
 478         dev_err(&chip->dev, "Operation Timed out\n");
 479         rc = -ETIME;
 480         goto out;
 481
 482 out_recv:
 483         len = chip->ops->recv(chip, (u8 *) buf, bufsiz);
 484         if (len < 0) {
 485                 rc = len;
 486                 dev_err(&chip->dev,
 487                         "tpm_transmit: tpm_recv: error %d\n", rc);
 488                 goto out;
 489         } else if (len < TPM_HEADER_SIZE) {
 490                 rc = -EFAULT;
 491                 goto out;
 492         }
 493
 494         if (len != be32_to_cpu(header->length)) {
 495                 rc = -EFAULT;
 496                 goto out;
 497         }
 498
 499         rc = tpm2_commit_space(chip, space, ordinal, buf, &len);
 500
 501 out:
 502         if (need_locality && chip->ops->relinquish_locality) {
 503                 chip->ops->relinquish_locality(chip, chip->locality);
 504                 chip->locality = -1;
 505         }
 506 out_no_locality:
 507         if (chip->ops->clk_enable != NULL)
 508                 chip->ops->clk_enable(chip, false);
 509
 510         if (chip->dev.parent)
 511                 pm_runtime_put_sync(chip->dev.parent);
 512
 513         if (!(flags & TPM_TRANSMIT_UNLOCKED))
 514                 mutex_unlock(&chip->tpm_mutex);
 515         return rc ? rc : len;
 516 }
 517
 518 /**
 519  * tmp_transmit_cmd - send a tpm command to the device
 520  *    The function extracts tpm out header return code
 521  *
 522  * @chip: TPM chip to use
 523  * @buf: TPM command buffer
 524  * @bufsiz: length of the buffer
 525  * @min_rsp_body_length: minimum expected length of response body
 526  * @flags: tpm transmit flags - bitmap
 527  * @desc: command description used in the error message
 528  *
 529  * Return:
 530  *     0 when the operation is successful.
 531  *     A negative number for system errors (errno).
 532  *     A positive number for a TPM error.
 533  */
 534 ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_space *space,
 535                          const void *buf, size_t bufsiz,
 536                          size_t min_rsp_body_length, unsigned int flags,
 537                          const char *desc)
 538 {
 539         const struct tpm_output_header *header = buf;
 540         int err;
 541         ssize_t len;
 542
 543         len = tpm_transmit(chip, space, (u8 *)buf, bufsiz, flags);
 544         if (len <  0)
 545                 return len;
 546
 547         err = be32_to_cpu(header->return_code);
 548         if (err != 0 && desc)
 549                 dev_err(&chip->dev, "A TPM error (%d) occurred %s\n", err,
 550                         desc);
 551         if (err)
 552                 return err;
 553
 554         if (len < min_rsp_body_length + TPM_HEADER_SIZE)
 555                 return -EFAULT;
 556
 557         return 0;
 558 }
 559 EXPORT_SYMBOL_GPL(tpm_transmit_cmd);
 560
 561 #define TPM_ORD_STARTUP 153
 562 #define TPM_ST_CLEAR 1
 563
 564 /**
 565  * tpm_startup - turn on the TPM
 566  * @chip: TPM chip to use
 567  *
 568  * Normally the firmware should start the TPM. This function is provided as a
 569  * workaround if this does not happen. A legal case for this could be for
 570  * example when a TPM emulator is used.
 571  *
 572  * Return: same as tpm_transmit_cmd()
 573  */
 574 int tpm_startup(struct tpm_chip *chip)
 575 {
 576         struct tpm_buf buf;
 577         int rc;
 578
 579         dev_info(&chip->dev, "starting up the TPM manually\n");
 580
 581         if (chip->flags & TPM_CHIP_FLAG_TPM2) {
 582                 rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_STARTUP);
 583                 if (rc < 0)
 584                         return rc;
 585
 586                 tpm_buf_append_u16(&buf, TPM2_SU_CLEAR);
 587         } else {
 588                 rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_STARTUP);
 589                 if (rc < 0)
 590                         return rc;
 591
 592                 tpm_buf_append_u16(&buf, TPM_ST_CLEAR);
 593         }
 594
 595         rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
 596                               "attempting to start the TPM");
 597
 598         tpm_buf_destroy(&buf);
 599         return rc;
 600 }
 601
 602 #define TPM_DIGEST_SIZE 20
 603 #define TPM_RET_CODE_IDX 6
 604 #define TPM_INTERNAL_RESULT_SIZE 200
 605 #define TPM_ORD_GET_CAP 101
 606 #define TPM_ORD_GET_RANDOM 70
 607
 608 static const struct tpm_input_header tpm_getcap_header = {
 609         .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
 610         .length = cpu_to_be32(22),
 611         .ordinal = cpu_to_be32(TPM_ORD_GET_CAP)
 612 };
 613
 614 ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
 615                    const char *desc, size_t min_cap_length)
 616 {
 617         struct tpm_buf buf;
 618         int rc;
 619
 620         rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_CAP);
 621         if (rc)
 622                 return rc;
 623
 624         if (subcap_id == TPM_CAP_VERSION_1_1 ||
 625             subcap_id == TPM_CAP_VERSION_1_2) {
 626                 tpm_buf_append_u32(&buf, subcap_id);
 627                 tpm_buf_append_u32(&buf, 0);
 628         } else {
 629                 if (subcap_id == TPM_CAP_FLAG_PERM ||
 630                     subcap_id == TPM_CAP_FLAG_VOL)
 631                         tpm_buf_append_u32(&buf, TPM_CAP_FLAG);
 632                 else
 633                         tpm_buf_append_u32(&buf, TPM_CAP_PROP);
 634
 635                 tpm_buf_append_u32(&buf, 4);
 636                 tpm_buf_append_u32(&buf, subcap_id);
 637         }
 638         rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE,
 639                               min_cap_length, 0, desc);
 640         if (!rc)
 641                 *cap = *(cap_t *)&buf.data[TPM_HEADER_SIZE + 4];
 642
 643         tpm_buf_destroy(&buf);
 644         return rc;
 645 }
 646 EXPORT_SYMBOL_GPL(tpm_getcap);
 647
 648 int tpm_get_timeouts(struct tpm_chip *chip)
 649 {
 650         cap_t cap;
 651         unsigned long timeout_old[4], timeout_chip[4], timeout_eff[4];
 652         ssize_t rc;
 653
 654         if (chip->flags & TPM_CHIP_FLAG_HAVE_TIMEOUTS)
 655                 return 0;
 656
 657         if (chip->flags & TPM_CHIP_FLAG_TPM2) {
 658                 /* Fixed timeouts for TPM2 */
 659                 chip->timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
 660                 chip->timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
 661                 chip->timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
 662                 chip->timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
 663                 chip->duration[TPM_SHORT] =
 664                     msecs_to_jiffies(TPM2_DURATION_SHORT);
 665                 chip->duration[TPM_MEDIUM] =
 666                     msecs_to_jiffies(TPM2_DURATION_MEDIUM);
 667                 chip->duration[TPM_LONG] =
 668                     msecs_to_jiffies(TPM2_DURATION_LONG);
 669
 670                 chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
 671                 return 0;
 672         }
 673
 674         rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, NULL,
 675                         sizeof(cap.timeout));
 676         if (rc == TPM_ERR_INVALID_POSTINIT) {
 677                 if (tpm_startup(chip))
 678                         return rc;
 679
 680                 rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
 681                                 "attempting to determine the timeouts",
 682                                 sizeof(cap.timeout));
 683         }
 684
 685         if (rc) {
 686                 dev_err(&chip->dev,
 687                         "A TPM error (%zd) occurred attempting to determine the timeouts\n",
 688                         rc);
 689                 return rc;
 690         }
 691
 692         timeout_old[0] = jiffies_to_usecs(chip->timeout_a);
 693         timeout_old[1] = jiffies_to_usecs(chip->timeout_b);
 694         timeout_old[2] = jiffies_to_usecs(chip->timeout_c);
 695         timeout_old[3] = jiffies_to_usecs(chip->timeout_d);
 696         timeout_chip[0] = be32_to_cpu(cap.timeout.a);
 697         timeout_chip[1] = be32_to_cpu(cap.timeout.b);
 698         timeout_chip[2] = be32_to_cpu(cap.timeout.c);
 699         timeout_chip[3] = be32_to_cpu(cap.timeout.d);
 700         memcpy(timeout_eff, timeout_chip, sizeof(timeout_eff));
 701
 702         /*
 703          * Provide ability for vendor overrides of timeout values in case
 704          * of misreporting.
 705          */
 706         if (chip->ops->update_timeouts != NULL)
 707                 chip->timeout_adjusted =
 708                         chip->ops->update_timeouts(chip, timeout_eff);
 709
 710         if (!chip->timeout_adjusted) {
 711                 /* Restore default if chip reported 0 */
 712                 int i;
 713
 714                 for (i = 0; i < ARRAY_SIZE(timeout_eff); i++) {
 715                         if (timeout_eff[i])
 716                                 continue;
 717
 718                         timeout_eff[i] = timeout_old[i];
 719                         chip->timeout_adjusted = true;
 720                 }
 721
 722                 if (timeout_eff[0] != 0 && timeout_eff[0] < 1000) {
 723                         /* timeouts in msec rather usec */
 724                         for (i = 0; i != ARRAY_SIZE(timeout_eff); i++)
 725                                 timeout_eff[i] *= 1000;
 726                         chip->timeout_adjusted = true;
 727                 }
 728         }
 729
 730         /* Report adjusted timeouts */
 731         if (chip->timeout_adjusted) {
 732                 dev_info(&chip->dev,
 733                          HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n",
 734                          timeout_chip[0], timeout_eff[0],
 735                          timeout_chip[1], timeout_eff[1],
 736                          timeout_chip[2], timeout_eff[2],
 737                          timeout_chip[3], timeout_eff[3]);
 738         }
 739
 740         chip->timeout_a = usecs_to_jiffies(timeout_eff[0]);
 741         chip->timeout_b = usecs_to_jiffies(timeout_eff[1]);
 742         chip->timeout_c = usecs_to_jiffies(timeout_eff[2]);
 743         chip->timeout_d = usecs_to_jiffies(timeout_eff[3]);
 744
 745         rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap,
 746                         "attempting to determine the durations",
 747                         sizeof(cap.duration));
 748         if (rc)
 749                 return rc;
 750
 751         chip->duration[TPM_SHORT] =
 752                 usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short));
 753         chip->duration[TPM_MEDIUM] =
 754                 usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium));
 755         chip->duration[TPM_LONG] =
 756                 usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long));
 757
 758         /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
 759          * value wrong and apparently reports msecs rather than usecs. So we
 760          * fix up the resulting too-small TPM_SHORT value to make things work.
 761          * We also scale the TPM_MEDIUM and -_LONG values by 1000.
 762          */
 763         if (chip->duration[TPM_SHORT] < (HZ / 100)) {
 764                 chip->duration[TPM_SHORT] = HZ;
 765                 chip->duration[TPM_MEDIUM] *= 1000;
 766                 chip->duration[TPM_LONG] *= 1000;
 767                 chip->duration_adjusted = true;
 768                 dev_info(&chip->dev, "Adjusting TPM timeout parameters.");
 769         }
 770
 771         chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
 772         return 0;
 773 }
 774 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
 775
 776 #define TPM_ORD_CONTINUE_SELFTEST 83
 777 #define CONTINUE_SELFTEST_RESULT_SIZE 10
 778
 779 static const struct tpm_input_header continue_selftest_header = {
 780         .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
 781         .length = cpu_to_be32(10),
 782         .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
 783 };
 784
 785 /**
 786  * tpm_continue_selftest -- run TPM's selftest
 787  * @chip: TPM chip to use
 788  *
 789  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
 790  * a TPM error code.
 791  */
 792 static int tpm_continue_selftest(struct tpm_chip *chip)
 793 {
 794         int rc;
 795         struct tpm_cmd_t cmd;
 796
 797         cmd.header.in = continue_selftest_header;
 798         rc = tpm_transmit_cmd(chip, NULL, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
 799                               0, 0, "continue selftest");
 800         return rc;
 801 }
 802
 803 #define TPM_ORDINAL_PCRREAD 21
 804 #define READ_PCR_RESULT_SIZE 30
 805 #define READ_PCR_RESULT_BODY_SIZE 20
 806 static const struct tpm_input_header pcrread_header = {
 807         .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
 808         .length = cpu_to_be32(14),
 809         .ordinal = cpu_to_be32(TPM_ORDINAL_PCRREAD)
 810 };
 811
 812 int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 813 {
 814         int rc;
 815         struct tpm_cmd_t cmd;
 816
 817         cmd.header.in = pcrread_header;
 818         cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
 819         rc = tpm_transmit_cmd(chip, NULL, &cmd, READ_PCR_RESULT_SIZE,
 820                               READ_PCR_RESULT_BODY_SIZE, 0,
 821                               "attempting to read a pcr value");
 822
 823         if (rc == 0)
 824                 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
 825                        TPM_DIGEST_SIZE);
 826         return rc;
 827 }
 828
 829 /**
 830  * tpm_is_tpm2 - do we a have a TPM2 chip?
 831  * @chip:       a &struct tpm_chip instance, %NULL for the default chip
 832  *
 833  * Return:
 834  * 1 if we have a TPM2 chip.
 835  * 0 if we don't have a TPM2 chip.
 836  * A negative number for system errors (errno).
 837  */
 838 int tpm_is_tpm2(struct tpm_chip *chip)
 839 {
 840         int rc;
 841
 842         chip = tpm_chip_find_get(chip);
 843         if (!chip)
 844                 return -ENODEV;
 845
 846         rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0;
 847
 848         tpm_put_ops(chip);
 849
 850         return rc;
 851 }
 852 EXPORT_SYMBOL_GPL(tpm_is_tpm2);
 853
 854 /**
 855  * tpm_pcr_read - read a PCR value from SHA1 bank
 856  * @chip:       a &struct tpm_chip instance, %NULL for the default chip
 857  * @pcr_idx:    the PCR to be retrieved
 858  * @res_buf:    the value of the PCR
 859  *
 860  * Return: same as with tpm_transmit_cmd()
 861  */
 862 int tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 863 {
 864         int rc;
 865
 866         chip = tpm_chip_find_get(chip);
 867         if (!chip)
 868                 return -ENODEV;
 869         if (chip->flags & TPM_CHIP_FLAG_TPM2)
 870                 rc = tpm2_pcr_read(chip, pcr_idx, res_buf);
 871         else
 872                 rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf);
 873         tpm_put_ops(chip);
 874         return rc;
 875 }
 876 EXPORT_SYMBOL_GPL(tpm_pcr_read);
 877
 878 #define TPM_ORD_PCR_EXTEND 20
 879 #define EXTEND_PCR_RESULT_SIZE 34
 880 #define EXTEND_PCR_RESULT_BODY_SIZE 20
 881 static const struct tpm_input_header pcrextend_header = {
 882         .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
 883         .length = cpu_to_be32(34),
 884         .ordinal = cpu_to_be32(TPM_ORD_PCR_EXTEND)
 885 };
 886
 887 static int tpm1_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash,
 888                            char *log_msg)
 889 {
 890         struct tpm_buf buf;
 891         int rc;
 892
 893         rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_PCR_EXTEND);
 894         if (rc)
 895                 return rc;
 896
 897         tpm_buf_append_u32(&buf, pcr_idx);
 898         tpm_buf_append(&buf, hash, TPM_DIGEST_SIZE);
 899
 900         rc = tpm_transmit_cmd(chip, NULL, buf.data, EXTEND_PCR_RESULT_SIZE,
 901                               EXTEND_PCR_RESULT_BODY_SIZE, 0, log_msg);
 902         tpm_buf_destroy(&buf);
 903         return rc;
 904 }
 905
 906 /**
 907  * tpm_pcr_extend - extend a PCR value in SHA1 bank.
 908  * @chip:       a &struct tpm_chip instance, %NULL for the default chip
 909  * @pcr_idx:    the PCR to be retrieved
 910  * @hash:       the hash value used to extend the PCR value
 911  *
 912  * Note: with TPM 2.0 extends also those banks with a known digest size to the
 913  * cryto subsystem in order to prevent malicious use of those PCR banks. In the
 914  * future we should dynamically determine digest sizes.
 915  *
 916  * Return: same as with tpm_transmit_cmd()
 917  */
 918 int tpm_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash)
 919 {
 920         int rc;
 921         struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)];
 922         u32 count = 0;
 923         int i;
 924
 925         chip = tpm_chip_find_get(chip);
 926         if (!chip)
 927                 return -ENODEV;
 928
 929         if (chip->flags & TPM_CHIP_FLAG_TPM2) {
 930                 memset(digest_list, 0, sizeof(digest_list));
 931
 932                 for (i = 0; i < ARRAY_SIZE(chip->active_banks) &&
 933                             chip->active_banks[i] != TPM2_ALG_ERROR; i++) {
 934                         digest_list[i].alg_id = chip->active_banks[i];
 935                         memcpy(digest_list[i].digest, hash, TPM_DIGEST_SIZE);
 936                         count++;
 937                 }
 938
 939                 rc = tpm2_pcr_extend(chip, pcr_idx, count, digest_list);
 940                 tpm_put_ops(chip);
 941                 return rc;
 942         }
 943
 944         rc = tpm1_pcr_extend(chip, pcr_idx, hash,
 945                              "attempting extend a PCR value");
 946         tpm_put_ops(chip);
 947         return rc;
 948 }
 949 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
 950
 951 /**
 952  * tpm_do_selftest - have the TPM continue its selftest and wait until it
 953  *                   can receive further commands
 954  * @chip: TPM chip to use
 955  *
 956  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
 957  * a TPM error code.
 958  */
 959 int tpm_do_selftest(struct tpm_chip *chip)
 960 {
 961         int rc;
 962         unsigned int loops;
 963         unsigned int delay_msec = 100;
 964         unsigned long duration;
 965         u8 dummy[TPM_DIGEST_SIZE];
 966
 967         duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST);
 968
 969         loops = jiffies_to_msecs(duration) / delay_msec;
 970
 971         rc = tpm_continue_selftest(chip);
 972         /* This may fail if there was no TPM driver during a suspend/resume
 973          * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
 974          */
 975         if (rc)
 976                 return rc;
 977
 978         do {
 979                 /* Attempt to read a PCR value */
 980                 rc = tpm_pcr_read_dev(chip, 0, dummy);
 981
 982                 /* Some buggy TPMs will not respond to tpm_tis_ready() for
 983                  * around 300ms while the self test is ongoing, keep trying
 984                  * until the self test duration expires. */
 985                 if (rc == -ETIME) {
 986                         dev_info(
 987                             &chip->dev, HW_ERR
 988                             "TPM command timed out during continue self test");
 989                         tpm_msleep(delay_msec);
 990                         continue;
 991                 }
 992
 993                 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
 994                         dev_info(&chip->dev,
 995                                  "TPM is disabled/deactivated (0x%X)\n", rc);
 996                         /* TPM is disabled and/or deactivated; driver can
 997                          * proceed and TPM does handle commands for
 998                          * suspend/resume correctly
 999                          */
1000                         return 0;
1001                 }
1002                 if (rc != TPM_WARN_DOING_SELFTEST)
1003                         return rc;
1004                 tpm_msleep(delay_msec);
1005         } while (--loops > 0);
1006
1007         return rc;
1008 }
1009 EXPORT_SYMBOL_GPL(tpm_do_selftest);
1010
1011 /**
1012  * tpm1_auto_startup - Perform the standard automatic TPM initialization
1013  *                     sequence
1014  * @chip: TPM chip to use
1015  *
1016  * Returns 0 on success, < 0 in case of fatal error.
1017  */
1018 int tpm1_auto_startup(struct tpm_chip *chip)
1019 {
1020         int rc;
1021
1022         rc = tpm_get_timeouts(chip);
1023         if (rc)
1024                 goto out;
1025         rc = tpm_do_selftest(chip);
1026         if (rc) {
1027                 dev_err(&chip->dev, "TPM self test failed\n");
1028                 goto out;
1029         }
1030
1031         return rc;
1032 out:
1033         if (rc > 0)
1034                 rc = -ENODEV;
1035         return rc;
1036 }
1037
1038 /**
1039  * tpm_send - send a TPM command
1040  * @chip:       a &struct tpm_chip instance, %NULL for the default chip
1041  * @cmd:        a TPM command buffer
1042  * @buflen:     the length of the TPM command buffer
1043  *
1044  * Return: same as with tpm_transmit_cmd()
1045  */
1046 int tpm_send(struct tpm_chip *chip, void *cmd, size_t buflen)
1047 {
1048         int rc;
1049
1050         chip = tpm_chip_find_get(chip);
1051         if (!chip)
1052                 return -ENODEV;
1053
1054         rc = tpm_transmit_cmd(chip, NULL, cmd, buflen, 0, 0,
1055                               "attempting to a send a command");
1056         tpm_put_ops(chip);
1057         return rc;
1058 }
1059 EXPORT_SYMBOL_GPL(tpm_send);
1060
1061 #define TPM_ORD_SAVESTATE 152
1062 #define SAVESTATE_RESULT_SIZE 10
1063
1064 static const struct tpm_input_header savestate_header = {
1065         .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
1066         .length = cpu_to_be32(10),
1067         .ordinal = cpu_to_be32(TPM_ORD_SAVESTATE)
1068 };
1069
1070 /*
1071  * We are about to suspend. Save the TPM state
1072  * so that it can be restored.
1073  */
1074 int tpm_pm_suspend(struct device *dev)
1075 {
1076         struct tpm_chip *chip = dev_get_drvdata(dev);
1077         struct tpm_cmd_t cmd;
1078         int rc, try;
1079
1080         u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1081
1082         if (chip == NULL)
1083                 return -ENODEV;
1084
1085         if (chip->flags & TPM_CHIP_FLAG_ALWAYS_POWERED)
1086                 return 0;
1087
1088         if (chip->flags & TPM_CHIP_FLAG_TPM2) {
1089                 tpm2_shutdown(chip, TPM2_SU_STATE);
1090                 return 0;
1091         }
1092
1093         /* for buggy tpm, flush pcrs with extend to selected dummy */
1094         if (tpm_suspend_pcr)
1095                 rc = tpm1_pcr_extend(chip, tpm_suspend_pcr, dummy_hash,
1096                                      "extending dummy pcr before suspend");
1097
1098         /* now do the actual savestate */
1099         for (try = 0; try < TPM_RETRY; try++) {
1100                 cmd.header.in = savestate_header;
1101                 rc = tpm_transmit_cmd(chip, NULL, &cmd, SAVESTATE_RESULT_SIZE,
1102                                       0, 0, NULL);
1103
1104                 /*
1105                  * If the TPM indicates that it is too busy to respond to
1106                  * this command then retry before giving up.  It can take
1107                  * several seconds for this TPM to be ready.
1108                  *
1109                  * This can happen if the TPM has already been sent the
1110                  * SaveState command before the driver has loaded.  TCG 1.2
1111                  * specification states that any communication after SaveState
1112                  * may cause the TPM to invalidate previously saved state.
1113                  */
1114                 if (rc != TPM_WARN_RETRY)
1115                         break;
1116                 tpm_msleep(TPM_TIMEOUT_RETRY);
1117         }
1118
1119         if (rc)
1120                 dev_err(&chip->dev,
1121                         "Error (%d) sending savestate before suspend\n", rc);
1122         else if (try > 0)
1123                 dev_warn(&chip->dev, "TPM savestate took %dms\n",
1124                          try * TPM_TIMEOUT_RETRY);
1125
1126         return rc;
1127 }
1128 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1129
1130 /*
1131  * Resume from a power safe. The BIOS already restored
1132  * the TPM state.
1133  */
1134 int tpm_pm_resume(struct device *dev)
1135 {
1136         struct tpm_chip *chip = dev_get_drvdata(dev);
1137
1138         if (chip == NULL)
1139                 return -ENODEV;
1140
1141         return 0;
1142 }
1143 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1144
1145 #define TPM_GETRANDOM_RESULT_SIZE       18
1146 static const struct tpm_input_header tpm_getrandom_header = {
1147         .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
1148         .length = cpu_to_be32(14),
1149         .ordinal = cpu_to_be32(TPM_ORD_GET_RANDOM)
1150 };
1151
1152 /**
1153  * tpm_get_random() - get random bytes from the TPM's RNG
1154  * @chip:       a &struct tpm_chip instance, %NULL for the default chip
1155  * @out:        destination buffer for the random bytes
1156  * @max:        the max number of bytes to write to @out
1157  *
1158  * Return: same as with tpm_transmit_cmd()
1159  */
1160 int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max)
1161 {
1162         struct tpm_cmd_t tpm_cmd;
1163         u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA), rlength;
1164         int err, total = 0, retries = 5;
1165         u8 *dest = out;
1166
1167         if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
1168                 return -EINVAL;
1169
1170         chip = tpm_chip_find_get(chip);
1171         if (!chip)
1172                 return -ENODEV;
1173
1174         if (chip->flags & TPM_CHIP_FLAG_TPM2) {
1175                 err = tpm2_get_random(chip, out, max);
1176                 tpm_put_ops(chip);
1177                 return err;
1178         }
1179
1180         do {
1181                 tpm_cmd.header.in = tpm_getrandom_header;
1182                 tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
1183
1184                 err = tpm_transmit_cmd(chip, NULL, &tpm_cmd,
1185                                        TPM_GETRANDOM_RESULT_SIZE + num_bytes,
1186                                        offsetof(struct tpm_getrandom_out,
1187                                                 rng_data),
1188                                        0, "attempting get random");
1189                 if (err)
1190                         break;
1191
1192                 recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
1193
1194                 rlength = be32_to_cpu(tpm_cmd.header.out.length);
1195                 if (rlength < offsetof(struct tpm_getrandom_out, rng_data) +
1196                               recd) {
1197                         total = -EFAULT;
1198                         break;
1199                 }
1200                 memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
1201
1202                 dest += recd;
1203                 total += recd;
1204                 num_bytes -= recd;
1205         } while (retries-- && total < max);
1206
1207         tpm_put_ops(chip);
1208         return total ? total : -EIO;
1209 }
1210 EXPORT_SYMBOL_GPL(tpm_get_random);
1211
1212 /**
1213  * tpm_seal_trusted() - seal a trusted key payload
1214  * @chip:       a &struct tpm_chip instance, %NULL for the default chip
1215  * @options:    authentication values and other options
1216  * @payload:    the key data in clear and encrypted form
1217  *
1218  * Note: only TPM 2.0 chip are supported. TPM 1.x implementation is located in
1219  * the keyring subsystem.
1220  *
1221  * Return: same as with tpm_transmit_cmd()
1222  */
1223 int tpm_seal_trusted(struct tpm_chip *chip, struct trusted_key_payload *payload,
1224                      struct trusted_key_options *options)
1225 {
1226         int rc;
1227
1228         chip = tpm_chip_find_get(chip);
1229         if (!chip || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1230                 return -ENODEV;
1231
1232         rc = tpm2_seal_trusted(chip, payload, options);
1233
1234         tpm_put_ops(chip);
1235         return rc;
1236 }
1237 EXPORT_SYMBOL_GPL(tpm_seal_trusted);
1238
1239 /**
1240  * tpm_unseal_trusted() - unseal a trusted key
1241  * @chip:       a &struct tpm_chip instance, %NULL for the default chip
1242  * @options:    authentication values and other options
1243  * @payload:    the key data in clear and encrypted form
1244  *
1245  * Note: only TPM 2.0 chip are supported. TPM 1.x implementation is located in
1246  * the keyring subsystem.
1247  *
1248  * Return: same as with tpm_transmit_cmd()
1249  */
1250 int tpm_unseal_trusted(struct tpm_chip *chip,
1251                        struct trusted_key_payload *payload,
1252                        struct trusted_key_options *options)
1253 {
1254         int rc;
1255
1256         chip = tpm_chip_find_get(chip);
1257         if (!chip || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1258                 return -ENODEV;
1259
1260         rc = tpm2_unseal_trusted(chip, payload, options);
1261
1262         tpm_put_ops(chip);
1263
1264         return rc;
1265 }
1266 EXPORT_SYMBOL_GPL(tpm_unseal_trusted);
1267
1268 static int __init tpm_init(void)
1269 {
1270         int rc;
1271
1272         tpm_class = class_create(THIS_MODULE, "tpm");
1273         if (IS_ERR(tpm_class)) {
1274                 pr_err("couldn't create tpm class\n");
1275                 return PTR_ERR(tpm_class);
1276         }
1277
1278         tpmrm_class = class_create(THIS_MODULE, "tpmrm");
1279         if (IS_ERR(tpmrm_class)) {
1280                 pr_err("couldn't create tpmrm class\n");
1281                 class_destroy(tpm_class);
1282                 return PTR_ERR(tpmrm_class);
1283         }
1284
1285         rc = alloc_chrdev_region(&tpm_devt, 0, 2*TPM_NUM_DEVICES, "tpm");
1286         if (rc < 0) {
1287                 pr_err("tpm: failed to allocate char dev region\n");
1288                 class_destroy(tpmrm_class);
1289                 class_destroy(tpm_class);
1290                 return rc;
1291         }
1292
1293         return 0;
1294 }
1295
1296 static void __exit tpm_exit(void)
1297 {
1298         idr_destroy(&dev_nums_idr);
1299         class_destroy(tpm_class);
1300         class_destroy(tpmrm_class);
1301         unregister_chrdev_region(tpm_devt, 2*TPM_NUM_DEVICES);
1302 }
1303
1304 subsys_initcall(tpm_init);
1305 module_exit(tpm_exit);
1306
1307 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1308 MODULE_DESCRIPTION("TPM Driver");
1309 MODULE_VERSION("2.0");
1310 MODULE_LICENSE("GPL");