drivers/char/tpm/tpm.c

   1 /*
   2  * Copyright (C) 2004 IBM Corporation
   3  *
   4  * Authors:
   5  * Leendert van Doorn <leendert@watson.ibm.com>
   6  * Dave Safford <safford@watson.ibm.com>
   7  * Reiner Sailer <sailer@watson.ibm.com>
   8  * Kylene Hall <kjhall@us.ibm.com>
   9  *
  10  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
  11  *
  12  * Device driver for TCG/TCPA TPM (trusted platform module).
  13  * Specifications at www.trustedcomputinggroup.org
  14  *
  15  * This program is free software; you can redistribute it and/or
  16  * modify it under the terms of the GNU General Public License as
  17  * published by the Free Software Foundation, version 2 of the
  18  * License.
  19  *
  20  * Note, the TPM chip is not interrupt driven (only polling)
  21  * and can have very long timeouts (minutes!). Hence the unusual
  22  * calls to msleep.
  23  *
  24  */
  25
  26 #include <linux/poll.h>
  27 #include <linux/slab.h>
  28 #include <linux/jiffies.h>
  29 #include <linux/mutex.h>
  30 #include <linux/spinlock.h>
  31 #include <linux/freezer.h>
  32
  33 #include "tpm.h"
  34
  35 enum tpm_const {
  36         TPM_MINOR = 224,        /* officially assigned */
  37         TPM_BUFSIZE = 4096,
  38         TPM_NUM_DEVICES = 256,
  39 };
  40
  41 enum tpm_duration {
  42         TPM_SHORT = 0,
  43         TPM_MEDIUM = 1,
  44         TPM_LONG = 2,
  45         TPM_UNDEFINED,
  46 };
  47
  48 #define TPM_MAX_ORDINAL 243
  49 #define TPM_MAX_PROTECTED_ORDINAL 12
  50 #define TPM_PROTECTED_ORDINAL_MASK 0xFF
  51
  52 /*
  53  * Bug workaround - some TPM's don't flush the most
  54  * recently changed pcr on suspend, so force the flush
  55  * with an extend to the selected _unused_ non-volatile pcr.
  56  */
  57 static int tpm_suspend_pcr;
  58 module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644);
  59 MODULE_PARM_DESC(suspend_pcr,
  60                  "PCR to use for dummy writes to faciltate flush on suspend.");
  61
  62 static LIST_HEAD(tpm_chip_list);
  63 static DEFINE_SPINLOCK(driver_lock);
  64 static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
  65
  66 /*
  67  * Array with one entry per ordinal defining the maximum amount
  68  * of time the chip could take to return the result.  The ordinal
  69  * designation of short, medium or long is defined in a table in
  70  * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
  71  * values of the SHORT, MEDIUM, and LONG durations are retrieved
  72  * from the chip during initialization with a call to tpm_get_timeouts.
  73  */
  74 static const u8 tpm_protected_ordinal_duration[TPM_MAX_PROTECTED_ORDINAL] = {
  75         TPM_UNDEFINED,          /* 0 */
  76         TPM_UNDEFINED,
  77         TPM_UNDEFINED,
  78         TPM_UNDEFINED,
  79         TPM_UNDEFINED,
  80         TPM_UNDEFINED,          /* 5 */
  81         TPM_UNDEFINED,
  82         TPM_UNDEFINED,
  83         TPM_UNDEFINED,
  84         TPM_UNDEFINED,
  85         TPM_SHORT,              /* 10 */
  86         TPM_SHORT,
  87 };
  88
  89 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
  90         TPM_UNDEFINED,          /* 0 */
  91         TPM_UNDEFINED,
  92         TPM_UNDEFINED,
  93         TPM_UNDEFINED,
  94         TPM_UNDEFINED,
  95         TPM_UNDEFINED,          /* 5 */
  96         TPM_UNDEFINED,
  97         TPM_UNDEFINED,
  98         TPM_UNDEFINED,
  99         TPM_UNDEFINED,
 100         TPM_SHORT,              /* 10 */
 101         TPM_SHORT,
 102         TPM_MEDIUM,
 103         TPM_LONG,
 104         TPM_LONG,
 105         TPM_MEDIUM,             /* 15 */
 106         TPM_SHORT,
 107         TPM_SHORT,
 108         TPM_MEDIUM,
 109         TPM_LONG,
 110         TPM_SHORT,              /* 20 */
 111         TPM_SHORT,
 112         TPM_MEDIUM,
 113         TPM_MEDIUM,
 114         TPM_MEDIUM,
 115         TPM_SHORT,              /* 25 */
 116         TPM_SHORT,
 117         TPM_MEDIUM,
 118         TPM_SHORT,
 119         TPM_SHORT,
 120         TPM_MEDIUM,             /* 30 */
 121         TPM_LONG,
 122         TPM_MEDIUM,
 123         TPM_SHORT,
 124         TPM_SHORT,
 125         TPM_SHORT,              /* 35 */
 126         TPM_MEDIUM,
 127         TPM_MEDIUM,
 128         TPM_UNDEFINED,
 129         TPM_UNDEFINED,
 130         TPM_MEDIUM,             /* 40 */
 131         TPM_LONG,
 132         TPM_MEDIUM,
 133         TPM_SHORT,
 134         TPM_SHORT,
 135         TPM_SHORT,              /* 45 */
 136         TPM_SHORT,
 137         TPM_SHORT,
 138         TPM_SHORT,
 139         TPM_LONG,
 140         TPM_MEDIUM,             /* 50 */
 141         TPM_MEDIUM,
 142         TPM_UNDEFINED,
 143         TPM_UNDEFINED,
 144         TPM_UNDEFINED,
 145         TPM_UNDEFINED,          /* 55 */
 146         TPM_UNDEFINED,
 147         TPM_UNDEFINED,
 148         TPM_UNDEFINED,
 149         TPM_UNDEFINED,
 150         TPM_MEDIUM,             /* 60 */
 151         TPM_MEDIUM,
 152         TPM_MEDIUM,
 153         TPM_SHORT,
 154         TPM_SHORT,
 155         TPM_MEDIUM,             /* 65 */
 156         TPM_UNDEFINED,
 157         TPM_UNDEFINED,
 158         TPM_UNDEFINED,
 159         TPM_UNDEFINED,
 160         TPM_SHORT,              /* 70 */
 161         TPM_SHORT,
 162         TPM_UNDEFINED,
 163         TPM_UNDEFINED,
 164         TPM_UNDEFINED,
 165         TPM_UNDEFINED,          /* 75 */
 166         TPM_UNDEFINED,
 167         TPM_UNDEFINED,
 168         TPM_UNDEFINED,
 169         TPM_UNDEFINED,
 170         TPM_LONG,               /* 80 */
 171         TPM_UNDEFINED,
 172         TPM_MEDIUM,
 173         TPM_LONG,
 174         TPM_SHORT,
 175         TPM_UNDEFINED,          /* 85 */
 176         TPM_UNDEFINED,
 177         TPM_UNDEFINED,
 178         TPM_UNDEFINED,
 179         TPM_UNDEFINED,
 180         TPM_SHORT,              /* 90 */
 181         TPM_SHORT,
 182         TPM_SHORT,
 183         TPM_SHORT,
 184         TPM_SHORT,
 185         TPM_UNDEFINED,          /* 95 */
 186         TPM_UNDEFINED,
 187         TPM_UNDEFINED,
 188         TPM_UNDEFINED,
 189         TPM_UNDEFINED,
 190         TPM_MEDIUM,             /* 100 */
 191         TPM_SHORT,
 192         TPM_SHORT,
 193         TPM_UNDEFINED,
 194         TPM_UNDEFINED,
 195         TPM_UNDEFINED,          /* 105 */
 196         TPM_UNDEFINED,
 197         TPM_UNDEFINED,
 198         TPM_UNDEFINED,
 199         TPM_UNDEFINED,
 200         TPM_SHORT,              /* 110 */
 201         TPM_SHORT,
 202         TPM_SHORT,
 203         TPM_SHORT,
 204         TPM_SHORT,
 205         TPM_SHORT,              /* 115 */
 206         TPM_SHORT,
 207         TPM_SHORT,
 208         TPM_UNDEFINED,
 209         TPM_UNDEFINED,
 210         TPM_LONG,               /* 120 */
 211         TPM_LONG,
 212         TPM_MEDIUM,
 213         TPM_UNDEFINED,
 214         TPM_SHORT,
 215         TPM_SHORT,              /* 125 */
 216         TPM_SHORT,
 217         TPM_LONG,
 218         TPM_SHORT,
 219         TPM_SHORT,
 220         TPM_SHORT,              /* 130 */
 221         TPM_MEDIUM,
 222         TPM_UNDEFINED,
 223         TPM_SHORT,
 224         TPM_MEDIUM,
 225         TPM_UNDEFINED,          /* 135 */
 226         TPM_UNDEFINED,
 227         TPM_UNDEFINED,
 228         TPM_UNDEFINED,
 229         TPM_UNDEFINED,
 230         TPM_SHORT,              /* 140 */
 231         TPM_SHORT,
 232         TPM_UNDEFINED,
 233         TPM_UNDEFINED,
 234         TPM_UNDEFINED,
 235         TPM_UNDEFINED,          /* 145 */
 236         TPM_UNDEFINED,
 237         TPM_UNDEFINED,
 238         TPM_UNDEFINED,
 239         TPM_UNDEFINED,
 240         TPM_SHORT,              /* 150 */
 241         TPM_MEDIUM,
 242         TPM_MEDIUM,
 243         TPM_SHORT,
 244         TPM_SHORT,
 245         TPM_UNDEFINED,          /* 155 */
 246         TPM_UNDEFINED,
 247         TPM_UNDEFINED,
 248         TPM_UNDEFINED,
 249         TPM_UNDEFINED,
 250         TPM_SHORT,              /* 160 */
 251         TPM_SHORT,
 252         TPM_SHORT,
 253         TPM_SHORT,
 254         TPM_UNDEFINED,
 255         TPM_UNDEFINED,          /* 165 */
 256         TPM_UNDEFINED,
 257         TPM_UNDEFINED,
 258         TPM_UNDEFINED,
 259         TPM_UNDEFINED,
 260         TPM_LONG,               /* 170 */
 261         TPM_UNDEFINED,
 262         TPM_UNDEFINED,
 263         TPM_UNDEFINED,
 264         TPM_UNDEFINED,
 265         TPM_UNDEFINED,          /* 175 */
 266         TPM_UNDEFINED,
 267         TPM_UNDEFINED,
 268         TPM_UNDEFINED,
 269         TPM_UNDEFINED,
 270         TPM_MEDIUM,             /* 180 */
 271         TPM_SHORT,
 272         TPM_MEDIUM,
 273         TPM_MEDIUM,
 274         TPM_MEDIUM,
 275         TPM_MEDIUM,             /* 185 */
 276         TPM_SHORT,
 277         TPM_UNDEFINED,
 278         TPM_UNDEFINED,
 279         TPM_UNDEFINED,
 280         TPM_UNDEFINED,          /* 190 */
 281         TPM_UNDEFINED,
 282         TPM_UNDEFINED,
 283         TPM_UNDEFINED,
 284         TPM_UNDEFINED,
 285         TPM_UNDEFINED,          /* 195 */
 286         TPM_UNDEFINED,
 287         TPM_UNDEFINED,
 288         TPM_UNDEFINED,
 289         TPM_UNDEFINED,
 290         TPM_SHORT,              /* 200 */
 291         TPM_UNDEFINED,
 292         TPM_UNDEFINED,
 293         TPM_UNDEFINED,
 294         TPM_SHORT,
 295         TPM_SHORT,              /* 205 */
 296         TPM_SHORT,
 297         TPM_SHORT,
 298         TPM_SHORT,
 299         TPM_SHORT,
 300         TPM_MEDIUM,             /* 210 */
 301         TPM_UNDEFINED,
 302         TPM_MEDIUM,
 303         TPM_MEDIUM,
 304         TPM_MEDIUM,
 305         TPM_UNDEFINED,          /* 215 */
 306         TPM_MEDIUM,
 307         TPM_UNDEFINED,
 308         TPM_UNDEFINED,
 309         TPM_SHORT,
 310         TPM_SHORT,              /* 220 */
 311         TPM_SHORT,
 312         TPM_SHORT,
 313         TPM_SHORT,
 314         TPM_SHORT,
 315         TPM_UNDEFINED,          /* 225 */
 316         TPM_UNDEFINED,
 317         TPM_UNDEFINED,
 318         TPM_UNDEFINED,
 319         TPM_UNDEFINED,
 320         TPM_SHORT,              /* 230 */
 321         TPM_LONG,
 322         TPM_MEDIUM,
 323         TPM_UNDEFINED,
 324         TPM_UNDEFINED,
 325         TPM_UNDEFINED,          /* 235 */
 326         TPM_UNDEFINED,
 327         TPM_UNDEFINED,
 328         TPM_UNDEFINED,
 329         TPM_UNDEFINED,
 330         TPM_SHORT,              /* 240 */
 331         TPM_UNDEFINED,
 332         TPM_MEDIUM,
 333 };
 334
 335 static void user_reader_timeout(unsigned long ptr)
 336 {
 337         struct tpm_chip *chip = (struct tpm_chip *) ptr;
 338
 339         schedule_work(&chip->work);
 340 }
 341
 342 static void timeout_work(struct work_struct *work)
 343 {
 344         struct tpm_chip *chip = container_of(work, struct tpm_chip, work);
 345
 346         mutex_lock(&chip->buffer_mutex);
 347         atomic_set(&chip->data_pending, 0);
 348         memset(chip->data_buffer, 0, TPM_BUFSIZE);
 349         mutex_unlock(&chip->buffer_mutex);
 350 }
 351
 352 static void set_needs_resume(struct tpm_chip *chip)
 353 {
 354         mutex_lock(&chip->resume_mutex);
 355         chip->needs_resume = 1;
 356         mutex_unlock(&chip->resume_mutex);
 357 }
 358
 359 #define TPM_ORD_CONTINUE_SELFTEST 83
 360 #define CONTINUE_SELFTEST_RESULT_SIZE 10
 361
 362 #define TPM_INTERNAL_RESULT_SIZE 200
 363 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
 364 #define TPM_ORD_GET_CAP cpu_to_be32(101)
 365
 366 static const struct tpm_input_header tpm_getcap_header = {
 367         .tag = TPM_TAG_RQU_COMMAND,
 368         .length = cpu_to_be32(22),
 369         .ordinal = TPM_ORD_GET_CAP
 370 };
 371
 372 static struct tpm_input_header continue_selftest_header = {
 373         .tag = TPM_TAG_RQU_COMMAND,
 374         .length = cpu_to_be32(10),
 375         .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
 376 };
 377
 378 /*
 379  * Internal kernel interface to transmit TPM commands
 380  */
 381 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
 382                             size_t bufsiz)
 383 {
 384         ssize_t rc;
 385         u32 count, ordinal;
 386         unsigned long stop;
 387
 388         if (bufsiz > TPM_BUFSIZE)
 389                 bufsiz = TPM_BUFSIZE;
 390
 391         count = be32_to_cpu(*((__be32 *) (buf + 2)));
 392         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
 393         if (count == 0)
 394                 return -ENODATA;
 395         if (count > bufsiz) {
 396                 dev_err(chip->dev,
 397                         "invalid count value %x %zx \n", count, bufsiz);
 398                 return -E2BIG;
 399         }
 400
 401         mutex_lock(&chip->tpm_mutex);
 402
 403         if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
 404                 dev_err(chip->dev,
 405                         "tpm_transmit: tpm_send: error %zd\n", rc);
 406                 goto out;
 407         }
 408
 409         if (chip->vendor.irq)
 410                 goto out_recv;
 411
 412         stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
 413         do {
 414                 u8 status = chip->vendor.status(chip);
 415                 if ((status & chip->vendor.req_complete_mask) ==
 416                     chip->vendor.req_complete_val)
 417                         goto out_recv;
 418
 419                 if ((status == chip->vendor.req_canceled)) {
 420                         dev_err(chip->dev, "Operation Canceled\n");
 421                         rc = -ECANCELED;
 422                         goto out;
 423                 }
 424
 425                 msleep(TPM_TIMEOUT);    /* CHECK */
 426                 rmb();
 427         } while (time_before(jiffies, stop));
 428
 429         chip->vendor.cancel(chip);
 430         dev_err(chip->dev, "Operation Timed out\n");
 431         rc = -ETIME;
 432         goto out;
 433
 434 out_recv:
 435         rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
 436         if (rc < 0)
 437                 dev_err(chip->dev,
 438                         "tpm_transmit: tpm_recv: error %zd\n", rc);
 439 out:
 440         mutex_unlock(&chip->tpm_mutex);
 441         return rc;
 442 }
 443
 444 void tpm_continue_selftest_nocheck(struct tpm_chip *chip)
 445 {
 446         struct tpm_cmd_t cmd;
 447         cmd.header.in = continue_selftest_header;
 448         tpm_transmit(chip, (u8 *) &cmd, CONTINUE_SELFTEST_RESULT_SIZE);
 449 }
 450 EXPORT_SYMBOL_GPL(tpm_continue_selftest_nocheck);
 451
 452 /* The maximum time in milliseconds that the TPM self test will take to
 453  * complete.  TODO(semenzato): 1s should be plenty for all TPMs, but how can we
 454  * ensure it?
 455  */
 456 #define TPM_SELF_TEST_DURATION_MSEC 1000
 457
 458 /* We don't want to wait for the self test to complete at resume, because it
 459  * impacts the resume speed.  TPM commands are infrequent so the wait is
 460  * usually not needed and is wasteful.  Instead, before we send any command, we
 461  * check that enough time has elapsed from the resume so that we are
 462  * comfortable that the self test has completed.  If not, we wait.  Unlike at
 463  * boot, here we don't check the return code of continue_self_test, so we can
 464  * use a code path which avoids recursion.  Furthermore, this only works when
 465  * ContinueSelfTest is blocking, that is it returns only after the self test
 466  * has completed, which is the case for the Infineon TPM.
 467  */
 468 static void resume_if_needed(struct tpm_chip *chip)
 469 {
 470         mutex_lock(&chip->resume_mutex);
 471         if (chip->needs_resume) {
 472                 dev_info(chip->dev, "waiting for TPM self test\n");
 473                 tpm_continue_selftest_nocheck(chip);
 474                 chip->needs_resume = 0;
 475                 dev_info(chip->dev, "TPM delayed resume completed\n");
 476         }
 477         mutex_unlock(&chip->resume_mutex);
 478 }
 479
 480 ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
 481                          int len, const char *desc)
 482 {
 483         int err;
 484
 485         resume_if_needed(chip);
 486
 487         len = tpm_transmit(chip,(u8 *) cmd, len);
 488         if (len <  0)
 489                 return len;
 490         else if (len < TPM_HEADER_SIZE)
 491                 return -EFAULT;
 492
 493         err = be32_to_cpu(cmd->header.out.return_code);
 494         if (err != 0)
 495                 dev_err(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
 496
 497         return err;
 498 }
 499 EXPORT_SYMBOL_GPL(tpm_transmit_cmd);
 500
 501 /**
 502  * tpm_continue_selftest -- run TPM's selftest
 503  * @chip: TPM chip to use
 504  *
 505  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
 506  * a TPM error code.
 507  */
 508 int tpm_continue_selftest(struct tpm_chip *chip)
 509 {
 510         int rc;
 511         struct tpm_cmd_t cmd;
 512
 513         cmd.header.in = continue_selftest_header;
 514         rc = tpm_transmit_cmd(chip, &cmd,
 515                               CONTINUE_SELFTEST_RESULT_SIZE, "continue selftest");
 516         return rc;
 517 }
 518 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
 519
 520 /*
 521  * Returns max number of jiffies to wait
 522  */
 523 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
 524                                            u32 ordinal)
 525 {
 526         int duration_idx = TPM_UNDEFINED;
 527         int duration = 0;
 528
 529         if (ordinal < TPM_MAX_ORDINAL)
 530                 duration_idx = tpm_ordinal_duration[ordinal];
 531         else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
 532                  TPM_MAX_PROTECTED_ORDINAL)
 533                 duration_idx =
 534                     tpm_protected_ordinal_duration[ordinal &
 535                                                    TPM_PROTECTED_ORDINAL_MASK];
 536
 537         if (duration_idx != TPM_UNDEFINED)
 538                 duration = chip->vendor.duration[duration_idx];
 539         if (duration <= 0)
 540                 return 2 * 60 * HZ;
 541         else
 542                 return duration;
 543 }
 544 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 545
 546 #define TPM_DIGEST_SIZE 20
 547 #define TPM_RET_CODE_IDX 6
 548
 549 enum tpm_capabilities {
 550         TPM_CAP_FLAG = cpu_to_be32(4),
 551         TPM_CAP_PROP = cpu_to_be32(5),
 552         CAP_VERSION_1_1 = cpu_to_be32(0x06),
 553         CAP_VERSION_1_2 = cpu_to_be32(0x1A)
 554 };
 555
 556 enum tpm_sub_capabilities {
 557         TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
 558         TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
 559         TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
 560         TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
 561         TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
 562         TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
 563         TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
 564
 565 };
 566
 567 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
 568                    const char *desc)
 569 {
 570         struct tpm_cmd_t tpm_cmd;
 571         int rc;
 572         struct tpm_chip *chip = dev_get_drvdata(dev);
 573
 574         tpm_cmd.header.in = tpm_getcap_header;
 575         if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
 576                 tpm_cmd.params.getcap_in.cap = subcap_id;
 577                 /*subcap field not necessary */
 578                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
 579                 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
 580         } else {
 581                 if (subcap_id == TPM_CAP_FLAG_PERM ||
 582                     subcap_id == TPM_CAP_FLAG_VOL)
 583                         tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
 584                 else
 585                         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 586                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 587                 tpm_cmd.params.getcap_in.subcap = subcap_id;
 588         }
 589         rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
 590         if (!rc)
 591                 *cap = tpm_cmd.params.getcap_out.cap;
 592         return rc;
 593 }
 594
 595 void tpm_gen_interrupt(struct tpm_chip *chip)
 596 {
 597         struct  tpm_cmd_t tpm_cmd;
 598         ssize_t rc;
 599
 600         tpm_cmd.header.in = tpm_getcap_header;
 601         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 602         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 603         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 604
 605         rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 606                               "attempting to determine the timeouts");
 607 }
 608 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
 609
 610 int tpm_get_timeouts(struct tpm_chip *chip)
 611 {
 612         struct tpm_cmd_t tpm_cmd;
 613         struct timeout_t *timeout_cap;
 614         struct duration_t *duration_cap;
 615         ssize_t rc;
 616         u32 timeout;
 617         unsigned int scale = 1;
 618
 619         tpm_cmd.header.in = tpm_getcap_header;
 620         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 621         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 622         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 623
 624         rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 625                               "attempting to determine the timeouts");
 626         if (rc)
 627                 goto duration;
 628
 629         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 630             be32_to_cpu(tpm_cmd.header.out.length)
 631             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
 632                 return -EINVAL;
 633
 634         timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
 635         /* Don't overwrite default if value is 0 */
 636         timeout = be32_to_cpu(timeout_cap->a);
 637         if (timeout && timeout < 1000) {
 638                 /* timeouts in msec rather usec */
 639                 scale = 1000;
 640                 chip->vendor.timeout_adjusted = true;
 641         }
 642         if (timeout)
 643                 chip->vendor.timeout_a = usecs_to_jiffies(timeout * scale);
 644         timeout = be32_to_cpu(timeout_cap->b);
 645         if (timeout)
 646                 chip->vendor.timeout_b = usecs_to_jiffies(timeout * scale);
 647         timeout = be32_to_cpu(timeout_cap->c);
 648         if (timeout)
 649                 chip->vendor.timeout_c = usecs_to_jiffies(timeout * scale);
 650         timeout = be32_to_cpu(timeout_cap->d);
 651         if (timeout)
 652                 chip->vendor.timeout_d = usecs_to_jiffies(timeout * scale);
 653
 654 duration:
 655         tpm_cmd.header.in = tpm_getcap_header;
 656         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 657         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 658         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
 659
 660         rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 661                               "attempting to determine the durations");
 662         if (rc)
 663                 return rc;
 664
 665         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 666             be32_to_cpu(tpm_cmd.header.out.length)
 667             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
 668                 return -EINVAL;
 669
 670         duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
 671         chip->vendor.duration[TPM_SHORT] =
 672             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
 673         chip->vendor.duration[TPM_MEDIUM] =
 674             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
 675         chip->vendor.duration[TPM_LONG] =
 676             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
 677
 678         /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
 679          * value wrong and apparently reports msecs rather than usecs. So we
 680          * fix up the resulting too-small TPM_SHORT value to make things work.
 681          * We also scale the TPM_MEDIUM and -_LONG values by 1000.
 682          */
 683         if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
 684                 chip->vendor.duration[TPM_SHORT] = HZ;
 685                 chip->vendor.duration[TPM_MEDIUM] *= 1000;
 686                 chip->vendor.duration[TPM_LONG] *= 1000;
 687                 chip->vendor.duration_adjusted = true;
 688                 dev_info(chip->dev, "Adjusting TPM timeout parameters.\n");
 689         }
 690         return 0;
 691 }
 692 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
 693
 694 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
 695                         char *buf)
 696 {
 697         cap_t cap;
 698         ssize_t rc;
 699
 700         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 701                          "attempting to determine the permanent enabled state");
 702         if (rc)
 703                 return 0;
 704
 705         rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
 706         return rc;
 707 }
 708 EXPORT_SYMBOL_GPL(tpm_show_enabled);
 709
 710 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
 711                         char *buf)
 712 {
 713         cap_t cap;
 714         ssize_t rc;
 715
 716         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 717                          "attempting to determine the permanent active state");
 718         if (rc)
 719                 return 0;
 720
 721         rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
 722         return rc;
 723 }
 724 EXPORT_SYMBOL_GPL(tpm_show_active);
 725
 726 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
 727                         char *buf)
 728 {
 729         cap_t cap;
 730         ssize_t rc;
 731
 732         rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
 733                          "attempting to determine the owner state");
 734         if (rc)
 735                 return 0;
 736
 737         rc = sprintf(buf, "%d\n", cap.owned);
 738         return rc;
 739 }
 740 EXPORT_SYMBOL_GPL(tpm_show_owned);
 741
 742 ssize_t tpm_show_temp_deactivated(struct device * dev,
 743                                 struct device_attribute * attr, char *buf)
 744 {
 745         cap_t cap;
 746         ssize_t rc;
 747
 748         rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
 749                          "attempting to determine the temporary state");
 750         if (rc)
 751                 return 0;
 752
 753         rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
 754         return rc;
 755 }
 756 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
 757
 758 /*
 759  * tpm_chip_find_get - return tpm_chip for given chip number
 760  */
 761 static struct tpm_chip *tpm_chip_find_get(int chip_num)
 762 {
 763         struct tpm_chip *pos, *chip = NULL;
 764
 765         rcu_read_lock();
 766         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
 767                 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
 768                         continue;
 769
 770                 if (try_module_get(pos->dev->driver->owner)) {
 771                         chip = pos;
 772                         break;
 773                 }
 774         }
 775         rcu_read_unlock();
 776         return chip;
 777 }
 778
 779 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
 780 #define READ_PCR_RESULT_SIZE 30
 781 static struct tpm_input_header pcrread_header = {
 782         .tag = TPM_TAG_RQU_COMMAND,
 783         .length = cpu_to_be32(14),
 784         .ordinal = TPM_ORDINAL_PCRREAD
 785 };
 786
 787 static int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 788 {
 789         int rc;
 790         struct tpm_cmd_t cmd;
 791
 792         cmd.header.in = pcrread_header;
 793         cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
 794         rc = tpm_transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
 795                               "attempting to read a pcr value");
 796
 797         if (rc == 0)
 798                 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
 799                        TPM_DIGEST_SIZE);
 800         return rc;
 801 }
 802
 803 /**
 804  * tpm_pcr_read - read a pcr value
 805  * @chip_num:   tpm idx # or ANY
 806  * @pcr_idx:    pcr idx to retrieve
 807  * @res_buf:    TPM_PCR value
 808  *              size of res_buf is 20 bytes (or NULL if you don't care)
 809  *
 810  * The TPM driver should be built-in, but for whatever reason it
 811  * isn't, protect against the chip disappearing, by incrementing
 812  * the module usage count.
 813  */
 814 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
 815 {
 816         struct tpm_chip *chip;
 817         int rc;
 818
 819         chip = tpm_chip_find_get(chip_num);
 820         if (chip == NULL)
 821                 return -ENODEV;
 822         rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
 823         tpm_chip_put(chip);
 824         return rc;
 825 }
 826 EXPORT_SYMBOL_GPL(tpm_pcr_read);
 827
 828 /**
 829  * tpm_pcr_extend - extend pcr value with hash
 830  * @chip_num:   tpm idx # or AN&
 831  * @pcr_idx:    pcr idx to extend
 832  * @hash:       hash value used to extend pcr value
 833  *
 834  * The TPM driver should be built-in, but for whatever reason it
 835  * isn't, protect against the chip disappearing, by incrementing
 836  * the module usage count.
 837  */
 838 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
 839 #define EXTEND_PCR_RESULT_SIZE 34
 840 static struct tpm_input_header pcrextend_header = {
 841         .tag = TPM_TAG_RQU_COMMAND,
 842         .length = cpu_to_be32(34),
 843         .ordinal = TPM_ORD_PCR_EXTEND
 844 };
 845
 846 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
 847 {
 848         struct tpm_cmd_t cmd;
 849         int rc;
 850         struct tpm_chip *chip;
 851
 852         chip = tpm_chip_find_get(chip_num);
 853         if (chip == NULL)
 854                 return -ENODEV;
 855
 856         cmd.header.in = pcrextend_header;
 857         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
 858         memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
 859         rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
 860                               "attempting extend a PCR value");
 861
 862         tpm_chip_put(chip);
 863         return rc;
 864 }
 865 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
 866
 867 /**
 868  * tpm_do_selftest - have the TPM continue its selftest and wait until it
 869  *                   can receive further commands
 870  * @chip: TPM chip to use
 871  *
 872  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
 873  * a TPM error code.
 874  */
 875 int tpm_do_selftest(struct tpm_chip *chip)
 876 {
 877         int rc;
 878         u8 digest[TPM_DIGEST_SIZE];
 879         unsigned int loops;
 880         unsigned int delay_msec = 1000;
 881         unsigned long duration;
 882
 883         duration = tpm_calc_ordinal_duration(chip,
 884                                              TPM_ORD_CONTINUE_SELFTEST);
 885
 886         loops = jiffies_to_msecs(duration) / delay_msec;
 887
 888         rc = tpm_continue_selftest(chip);
 889         /* This may fail if there was no TPM driver during a suspend/resume
 890          * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
 891          */
 892         if (rc)
 893                 return rc;
 894
 895         do {
 896                 rc = __tpm_pcr_read(chip, 0, digest);
 897                 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
 898                         dev_info(chip->dev,
 899                                  "TPM is disabled/deactivated (0x%X)\n", rc);
 900                         /* TPM is disabled and/or deactivated; driver can
 901                          * proceed and TPM does handle commands for
 902                          * suspend/resume correctly
 903                          */
 904                         return 0;
 905                 }
 906                 if (rc != TPM_WARN_DOING_SELFTEST)
 907                         return rc;
 908                 msleep(delay_msec);
 909         } while (--loops > 0);
 910
 911         return rc;
 912 }
 913 EXPORT_SYMBOL_GPL(tpm_do_selftest);
 914
 915 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
 916 {
 917         struct tpm_chip *chip;
 918         int rc;
 919
 920         chip = tpm_chip_find_get(chip_num);
 921         if (chip == NULL)
 922                 return -ENODEV;
 923
 924         rc = tpm_transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
 925
 926         tpm_chip_put(chip);
 927         return rc;
 928 }
 929 EXPORT_SYMBOL_GPL(tpm_send);
 930
 931 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
 932                       char *buf)
 933 {
 934         cap_t cap;
 935         u8 digest[TPM_DIGEST_SIZE];
 936         ssize_t rc;
 937         int i, j, num_pcrs;
 938         char *str = buf;
 939         struct tpm_chip *chip = dev_get_drvdata(dev);
 940
 941         rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
 942                         "attempting to determine the number of PCRS");
 943         if (rc)
 944                 return 0;
 945
 946         num_pcrs = be32_to_cpu(cap.num_pcrs);
 947         for (i = 0; i < num_pcrs; i++) {
 948                 rc = __tpm_pcr_read(chip, i, digest);
 949                 if (rc)
 950                         break;
 951                 str += sprintf(str, "PCR-%02d: ", i);
 952                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
 953                         str += sprintf(str, "%02X ", digest[j]);
 954                 str += sprintf(str, "\n");
 955         }
 956         return str - buf;
 957 }
 958 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 959
 960 #define  READ_PUBEK_RESULT_SIZE 314
 961 #define TPM_ORD_READPUBEK cpu_to_be32(124)
 962 struct tpm_input_header tpm_readpubek_header = {
 963         .tag = TPM_TAG_RQU_COMMAND,
 964         .length = cpu_to_be32(30),
 965         .ordinal = TPM_ORD_READPUBEK
 966 };
 967
 968 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
 969                        char *buf)
 970 {
 971         u8 *data;
 972         struct tpm_cmd_t tpm_cmd;
 973         ssize_t err;
 974         int i, rc;
 975         char *str = buf;
 976
 977         struct tpm_chip *chip = dev_get_drvdata(dev);
 978
 979         tpm_cmd.header.in = tpm_readpubek_header;
 980         err = tpm_transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
 981                                "attempting to read the PUBEK");
 982         if (err)
 983                 goto out;
 984
 985         /*
 986            ignore header 10 bytes
 987            algorithm 32 bits (1 == RSA )
 988            encscheme 16 bits
 989            sigscheme 16 bits
 990            parameters (RSA 12->bytes: keybit, #primes, expbit)
 991            keylenbytes 32 bits
 992            256 byte modulus
 993            ignore checksum 20 bytes
 994          */
 995         data = tpm_cmd.params.readpubek_out_buffer;
 996         str +=
 997             sprintf(str,
 998                     "Algorithm: %02X %02X %02X %02X\n"
 999                     "Encscheme: %02X %02X\n"
1000                     "Sigscheme: %02X %02X\n"
1001                     "Parameters: %02X %02X %02X %02X "
1002                     "%02X %02X %02X %02X "
1003                     "%02X %02X %02X %02X\n"
1004                     "Modulus length: %d\n"
1005                     "Modulus:\n",
1006                     data[0], data[1], data[2], data[3],
1007                     data[4], data[5],
1008                     data[6], data[7],
1009                     data[12], data[13], data[14], data[15],
1010                     data[16], data[17], data[18], data[19],
1011                     data[20], data[21], data[22], data[23],
1012                     be32_to_cpu(*((__be32 *) (data + 24))));
1013
1014         for (i = 0; i < 256; i++) {
1015                 str += sprintf(str, "%02X ", data[i + 28]);
1016                 if ((i + 1) % 16 == 0)
1017                         str += sprintf(str, "\n");
1018         }
1019 out:
1020         rc = str - buf;
1021         return rc;
1022 }
1023 EXPORT_SYMBOL_GPL(tpm_show_pubek);
1024
1025
1026 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
1027                       char *buf)
1028 {
1029         cap_t cap;
1030         ssize_t rc;
1031         char *str = buf;
1032
1033         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
1034                         "attempting to determine the manufacturer");
1035         if (rc)
1036                 return 0;
1037         str += sprintf(str, "Manufacturer: 0x%x\n",
1038                        be32_to_cpu(cap.manufacturer_id));
1039
1040         rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
1041                         "attempting to determine the 1.1 version");
1042         if (rc)
1043                 return 0;
1044         str += sprintf(str,
1045                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
1046                        cap.tpm_version.Major, cap.tpm_version.Minor,
1047                        cap.tpm_version.revMajor, cap.tpm_version.revMinor);
1048         return str - buf;
1049 }
1050 EXPORT_SYMBOL_GPL(tpm_show_caps);
1051
1052 ssize_t tpm_show_caps_1_2(struct device * dev,
1053                           struct device_attribute * attr, char *buf)
1054 {
1055         cap_t cap;
1056         ssize_t rc;
1057         char *str = buf;
1058
1059         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
1060                         "attempting to determine the manufacturer");
1061         if (rc)
1062                 return 0;
1063         str += sprintf(str, "Manufacturer: 0x%x\n",
1064                        be32_to_cpu(cap.manufacturer_id));
1065         rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
1066                          "attempting to determine the 1.2 version");
1067         if (rc)
1068                 return 0;
1069         str += sprintf(str,
1070                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
1071                        cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
1072                        cap.tpm_version_1_2.revMajor,
1073                        cap.tpm_version_1_2.revMinor);
1074         return str - buf;
1075 }
1076 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
1077
1078 ssize_t tpm_show_durations(struct device *dev, struct device_attribute *attr,
1079                           char *buf)
1080 {
1081         struct tpm_chip *chip = dev_get_drvdata(dev);
1082
1083         if (chip->vendor.duration[TPM_LONG] == 0)
1084                 return 0;
1085
1086         return sprintf(buf, "%d %d %d [%s]\n",
1087                        jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
1088                        jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
1089                        jiffies_to_usecs(chip->vendor.duration[TPM_LONG]),
1090                        chip->vendor.duration_adjusted
1091                        ? "adjusted" : "original");
1092 }
1093 EXPORT_SYMBOL_GPL(tpm_show_durations);
1094
1095 ssize_t tpm_show_timeouts(struct device *dev, struct device_attribute *attr,
1096                           char *buf)
1097 {
1098         struct tpm_chip *chip = dev_get_drvdata(dev);
1099
1100         return sprintf(buf, "%d %d %d %d [%s]\n",
1101                        jiffies_to_usecs(chip->vendor.timeout_a),
1102                        jiffies_to_usecs(chip->vendor.timeout_b),
1103                        jiffies_to_usecs(chip->vendor.timeout_c),
1104                        jiffies_to_usecs(chip->vendor.timeout_d),
1105                        chip->vendor.timeout_adjusted
1106                        ? "adjusted" : "original");
1107 }
1108 EXPORT_SYMBOL_GPL(tpm_show_timeouts);
1109
1110 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
1111                         const char *buf, size_t count)
1112 {
1113         struct tpm_chip *chip = dev_get_drvdata(dev);
1114         if (chip == NULL)
1115                 return 0;
1116
1117         chip->vendor.cancel(chip);
1118         return count;
1119 }
1120 EXPORT_SYMBOL_GPL(tpm_store_cancel);
1121
1122 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
1123                          wait_queue_head_t *queue)
1124 {
1125         unsigned long stop;
1126         long rc;
1127         u8 status;
1128
1129         /* check current status */
1130         status = chip->vendor.status(chip);
1131         if ((status & mask) == mask)
1132                 return 0;
1133
1134         stop = jiffies + timeout;
1135
1136         if (chip->vendor.irq) {
1137 again:
1138                 timeout = stop - jiffies;
1139                 if ((long)timeout <= 0)
1140                         return -ETIME;
1141                 rc = wait_event_interruptible_timeout(*queue,
1142                                                       ((chip->vendor.status(chip)
1143                                                       & mask) == mask),
1144                                                       timeout);
1145                 if (rc > 0)
1146                         return 0;
1147                 if (rc == -ERESTARTSYS && freezing(current)) {
1148                         clear_thread_flag(TIF_SIGPENDING);
1149                         goto again;
1150                 }
1151         } else {
1152                 do {
1153                         msleep(TPM_TIMEOUT);
1154                         status = chip->vendor.status(chip);
1155                         if ((status & mask) == mask)
1156                                 return 0;
1157                 } while (time_before(jiffies, stop));
1158         }
1159         return -ETIME;
1160 }
1161 EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
1162 /*
1163  * Device file system interface to the TPM
1164  *
1165  * It's assured that the chip will be opened just once,
1166  * by the check of is_open variable, which is protected
1167  * by driver_lock.
1168  */
1169 int tpm_open(struct inode *inode, struct file *file)
1170 {
1171         int minor = iminor(inode);
1172         struct tpm_chip *chip = NULL, *pos;
1173
1174         rcu_read_lock();
1175         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
1176                 if (pos->vendor.miscdev.minor == minor) {
1177                         chip = pos;
1178                         get_device(chip->dev);
1179                         break;
1180                 }
1181         }
1182         rcu_read_unlock();
1183
1184         if (!chip)
1185                 return -ENODEV;
1186
1187         if (test_and_set_bit(0, &chip->is_open)) {
1188                 dev_dbg(chip->dev, "Another process owns this TPM\n");
1189                 put_device(chip->dev);
1190                 return -EBUSY;
1191         }
1192
1193         chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
1194         if (chip->data_buffer == NULL) {
1195                 clear_bit(0, &chip->is_open);
1196                 put_device(chip->dev);
1197                 return -ENOMEM;
1198         }
1199
1200         atomic_set(&chip->data_pending, 0);
1201
1202         file->private_data = chip;
1203         return 0;
1204 }
1205 EXPORT_SYMBOL_GPL(tpm_open);
1206
1207 /*
1208  * Called on file close
1209  */
1210 int tpm_release(struct inode *inode, struct file *file)
1211 {
1212         struct tpm_chip *chip = file->private_data;
1213
1214         del_singleshot_timer_sync(&chip->user_read_timer);
1215         flush_work_sync(&chip->work);
1216         file->private_data = NULL;
1217         atomic_set(&chip->data_pending, 0);
1218         kfree(chip->data_buffer);
1219         clear_bit(0, &chip->is_open);
1220         put_device(chip->dev);
1221         return 0;
1222 }
1223 EXPORT_SYMBOL_GPL(tpm_release);
1224
1225 ssize_t tpm_write(struct file *file, const char __user *buf,
1226                   size_t size, loff_t *off)
1227 {
1228         struct tpm_chip *chip = file->private_data;
1229         size_t in_size = size, out_size;
1230
1231         /* cannot perform a write until the read has cleared
1232            either via tpm_read or a user_read_timer timeout */
1233         while (atomic_read(&chip->data_pending) != 0)
1234                 msleep(TPM_TIMEOUT);
1235
1236         resume_if_needed(chip);
1237
1238         mutex_lock(&chip->buffer_mutex);
1239
1240         if (in_size > TPM_BUFSIZE)
1241                 in_size = TPM_BUFSIZE;
1242
1243         if (copy_from_user
1244             (chip->data_buffer, (void __user *) buf, in_size)) {
1245                 mutex_unlock(&chip->buffer_mutex);
1246                 return -EFAULT;
1247         }
1248
1249         /* atomic tpm command send and result receive */
1250         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1251
1252         atomic_set(&chip->data_pending, out_size);
1253         mutex_unlock(&chip->buffer_mutex);
1254
1255         /* Set a timeout by which the reader must come claim the result */
1256         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1257
1258         return in_size;
1259 }
1260 EXPORT_SYMBOL_GPL(tpm_write);
1261
1262 ssize_t tpm_read(struct file *file, char __user *buf,
1263                  size_t size, loff_t *off)
1264 {
1265         struct tpm_chip *chip = file->private_data;
1266         ssize_t ret_size;
1267         int rc;
1268
1269         del_singleshot_timer_sync(&chip->user_read_timer);
1270         flush_work_sync(&chip->work);
1271         ret_size = atomic_read(&chip->data_pending);
1272         /* TODO(wad): atomic_set should come AFTER the buffer is copied. */
1273         atomic_set(&chip->data_pending, 0);
1274         if (ret_size > 0) {     /* relay data */
1275                 ssize_t orig_ret_size = ret_size;
1276                 if (size < ret_size)
1277                         ret_size = size;
1278
1279                 mutex_lock(&chip->buffer_mutex);
1280                 rc = copy_to_user(buf, chip->data_buffer, ret_size);
1281                 memset(chip->data_buffer, 0, orig_ret_size);
1282                 if (rc)
1283                         ret_size = -EFAULT;
1284
1285                 mutex_unlock(&chip->buffer_mutex);
1286         }
1287
1288         return ret_size;
1289 }
1290 EXPORT_SYMBOL_GPL(tpm_read);
1291
1292 void tpm_remove_hardware(struct device *dev)
1293 {
1294         struct tpm_chip *chip = dev_get_drvdata(dev);
1295
1296         if (chip == NULL) {
1297                 dev_err(dev, "No device data found\n");
1298                 return;
1299         }
1300
1301         spin_lock(&driver_lock);
1302         list_del_rcu(&chip->list);
1303         spin_unlock(&driver_lock);
1304         synchronize_rcu();
1305
1306         misc_deregister(&chip->vendor.miscdev);
1307         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1308         tpm_bios_log_teardown(chip->bios_dir);
1309
1310         /* write it this way to be explicit (chip->dev == dev) */
1311         put_device(chip->dev);
1312 }
1313 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1314
1315 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1316 #define SAVESTATE_RESULT_SIZE 10
1317
1318 static struct tpm_input_header savestate_header = {
1319         .tag = TPM_TAG_RQU_COMMAND,
1320         .length = cpu_to_be32(10),
1321         .ordinal = TPM_ORD_SAVESTATE
1322 };
1323
1324 /*
1325  * We are about to suspend. Save the TPM state
1326  * so that it can be restored.
1327  */
1328 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1329 {
1330         struct tpm_chip *chip = dev_get_drvdata(dev);
1331         struct tpm_cmd_t cmd;
1332         int rc, try;
1333
1334         u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1335
1336         if (chip == NULL)
1337                 return -ENODEV;
1338
1339         /* for buggy tpm, flush pcrs with extend to selected dummy */
1340         if (tpm_suspend_pcr) {
1341                 cmd.header.in = pcrextend_header;
1342                 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1343                 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1344                        TPM_DIGEST_SIZE);
1345                 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1346                                       "extending dummy pcr before suspend");
1347         }
1348
1349         /* now do the actual savestate */
1350         for (try = 0; try < TPM_RETRY; try++) {
1351                 cmd.header.in = savestate_header;
1352                 rc = tpm_transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, NULL);
1353
1354                 /*
1355                  * If the TPM indicates that it is too busy to respond to
1356                  * this command then retry before giving up.  It can take
1357                  * several seconds for this TPM to be ready.
1358                  *
1359                  * This can happen if the TPM has already been sent the
1360                  * SaveState command before the driver has loaded.  TCG 1.2
1361                  * specification states that any communication after SaveState
1362                  * may cause the TPM to invalidate previously saved state.
1363                  */
1364                 if (rc != TPM_WARN_RETRY)
1365                         break;
1366                 msleep(TPM_TIMEOUT_RETRY);
1367         }
1368
1369         if (rc)
1370                 dev_err(chip->dev,
1371                         "Error (%d) sending savestate before suspend\n", rc);
1372         else if (try > 0)
1373                 dev_warn(chip->dev, "TPM savestate took %dms\n",
1374                          try * TPM_TIMEOUT_RETRY);
1375
1376         return rc;
1377 }
1378 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1379
1380 /*
1381  * Resume from a power safe. The BIOS already restored
1382  * the TPM state.
1383  */
1384 int tpm_pm_resume(struct device *dev)
1385 {
1386         struct tpm_chip *chip = dev_get_drvdata(dev);
1387
1388         if (chip == NULL)
1389                 return -ENODEV;
1390
1391         set_needs_resume(chip);
1392         return 0;
1393 }
1394 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1395
1396 /* In case vendor provided release function, call it too.*/
1397
1398 void tpm_dev_vendor_release(struct tpm_chip *chip)
1399 {
1400         if (chip->vendor.release)
1401                 chip->vendor.release(chip->dev);
1402
1403         clear_bit(chip->dev_num, dev_mask);
1404         kfree(chip->vendor.miscdev.name);
1405 }
1406 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1407
1408
1409 /*
1410  * Once all references to platform device are down to 0,
1411  * release all allocated structures.
1412  */
1413 void tpm_dev_release(struct device *dev)
1414 {
1415         struct tpm_chip *chip = dev_get_drvdata(dev);
1416
1417         tpm_dev_vendor_release(chip);
1418
1419         chip->release(dev);
1420         kfree(chip);
1421 }
1422 EXPORT_SYMBOL_GPL(tpm_dev_release);
1423
1424 /*
1425  * Called from tpm_<specific>.c probe function only for devices
1426  * the driver has determined it should claim.  Prior to calling
1427  * this function the specific probe function has called pci_enable_device
1428  * upon errant exit from this function specific probe function should call
1429  * pci_disable_device
1430  */
1431 struct tpm_chip *tpm_register_hardware(struct device *dev,
1432                                         const struct tpm_vendor_specific *entry)
1433 {
1434 #define DEVNAME_SIZE 7
1435
1436         char *devname;
1437         struct tpm_chip *chip;
1438
1439         /* Driver specific per-device data */
1440         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1441         devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1442
1443         if (chip == NULL || devname == NULL)
1444                 goto out_free;
1445
1446         mutex_init(&chip->buffer_mutex);
1447         mutex_init(&chip->tpm_mutex);
1448         mutex_init(&chip->resume_mutex);
1449         INIT_LIST_HEAD(&chip->list);
1450
1451         INIT_WORK(&chip->work, timeout_work);
1452
1453         setup_timer(&chip->user_read_timer, user_reader_timeout,
1454                         (unsigned long)chip);
1455
1456         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1457
1458         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1459
1460         if (chip->dev_num >= TPM_NUM_DEVICES) {
1461                 dev_err(dev, "No available tpm device numbers\n");
1462                 goto out_free;
1463         } else if (chip->dev_num == 0)
1464                 chip->vendor.miscdev.minor = TPM_MINOR;
1465         else
1466                 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1467
1468         set_bit(chip->dev_num, dev_mask);
1469
1470         scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1471         chip->vendor.miscdev.name = devname;
1472
1473         chip->vendor.miscdev.parent = dev;
1474         chip->dev = get_device(dev);
1475         chip->release = dev->release;
1476         dev->release = tpm_dev_release;
1477         dev_set_drvdata(dev, chip);
1478
1479         if (misc_register(&chip->vendor.miscdev)) {
1480                 dev_err(chip->dev,
1481                         "unable to misc_register %s, minor %d\n",
1482                         chip->vendor.miscdev.name,
1483                         chip->vendor.miscdev.minor);
1484                 put_device(chip->dev);
1485                 return NULL;
1486         }
1487
1488         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1489                 misc_deregister(&chip->vendor.miscdev);
1490                 put_device(chip->dev);
1491
1492                 return NULL;
1493         }
1494
1495         chip->bios_dir = tpm_bios_log_setup(devname);
1496
1497         /* Make chip available */
1498         spin_lock(&driver_lock);
1499         list_add_rcu(&chip->list, &tpm_chip_list);
1500         spin_unlock(&driver_lock);
1501
1502         return chip;
1503
1504 out_free:
1505         kfree(chip);
1506         kfree(devname);
1507         return NULL;
1508 }
1509 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1510
1511 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1512 MODULE_DESCRIPTION("TPM Driver");
1513 MODULE_VERSION("2.0");
1514 MODULE_LICENSE("GPL");