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->resume_time = jiffies;
 356         chip->needs_resume = 1;
 357         mutex_unlock(&chip->resume_mutex);
 358 }
 359
 360 #define TPM_ORD_CONTINUE_SELFTEST 83
 361 #define CONTINUE_SELFTEST_RESULT_SIZE 10
 362
 363 #define TPM_INTERNAL_RESULT_SIZE 200
 364 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
 365 #define TPM_ORD_GET_CAP cpu_to_be32(101)
 366
 367 static const struct tpm_input_header tpm_getcap_header = {
 368         .tag = TPM_TAG_RQU_COMMAND,
 369         .length = cpu_to_be32(22),
 370         .ordinal = TPM_ORD_GET_CAP
 371 };
 372
 373 static struct tpm_input_header continue_selftest_header = {
 374         .tag = TPM_TAG_RQU_COMMAND,
 375         .length = cpu_to_be32(10),
 376         .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
 377 };
 378
 379 /*
 380  * Internal kernel interface to transmit TPM commands
 381  */
 382 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
 383                             size_t bufsiz)
 384 {
 385         ssize_t rc;
 386         u32 count, ordinal;
 387         unsigned long stop;
 388
 389         if (bufsiz > TPM_BUFSIZE)
 390                 bufsiz = TPM_BUFSIZE;
 391
 392         count = be32_to_cpu(*((__be32 *) (buf + 2)));
 393         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
 394         if (count == 0)
 395                 return -ENODATA;
 396         if (count > bufsiz) {
 397                 dev_err(chip->dev,
 398                         "invalid count value %x %zx \n", count, bufsiz);
 399                 return -E2BIG;
 400         }
 401
 402         mutex_lock(&chip->tpm_mutex);
 403
 404         if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
 405                 dev_err(chip->dev,
 406                         "tpm_transmit: tpm_send: error %zd\n", rc);
 407                 goto out;
 408         }
 409
 410         if (chip->vendor.irq)
 411                 goto out_recv;
 412
 413         stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
 414         do {
 415                 u8 status = chip->vendor.status(chip);
 416                 if ((status & chip->vendor.req_complete_mask) ==
 417                     chip->vendor.req_complete_val)
 418                         goto out_recv;
 419
 420                 if ((status == chip->vendor.req_canceled)) {
 421                         dev_err(chip->dev, "Operation Canceled\n");
 422                         rc = -ECANCELED;
 423                         goto out;
 424                 }
 425
 426                 msleep(TPM_TIMEOUT);    /* CHECK */
 427                 rmb();
 428         } while (time_before(jiffies, stop));
 429
 430         chip->vendor.cancel(chip);
 431         dev_err(chip->dev, "Operation Timed out\n");
 432         rc = -ETIME;
 433         goto out;
 434
 435 out_recv:
 436         rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
 437         if (rc < 0)
 438                 dev_err(chip->dev,
 439                         "tpm_transmit: tpm_recv: error %zd\n", rc);
 440 out:
 441         mutex_unlock(&chip->tpm_mutex);
 442         return rc;
 443 }
 444
 445 void tpm_continue_selftest_nocheck(struct tpm_chip *chip)
 446 {
 447         struct tpm_cmd_t cmd;
 448         cmd.header.in = continue_selftest_header;
 449         tpm_transmit(chip, (u8 *) &cmd, CONTINUE_SELFTEST_RESULT_SIZE);
 450 }
 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                 /* If it's been TPM_SELF_TEST_DURATION_MSEC msec since resume,
 473                  * then selftest has completed and we don't need to wait.
 474                  */
 475                 if (jiffies - chip->resume_time <
 476                     msecs_to_jiffies(TPM_SELF_TEST_DURATION_MSEC)) {
 477                         dev_info(chip->dev, "waiting for TPM self test");
 478                         tpm_continue_selftest_nocheck(chip);
 479                 }
 480                 chip->needs_resume = 0;
 481                 dev_info(chip->dev, "TPM delayed resume completed");
 482         }
 483         mutex_unlock(&chip->resume_mutex);
 484 }
 485
 486 static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
 487                             int len, const char *desc)
 488 {
 489         int err;
 490
 491         resume_if_needed(chip);
 492
 493         len = tpm_transmit(chip,(u8 *) cmd, len);
 494         if (len <  0)
 495                 return len;
 496         else if (len < TPM_HEADER_SIZE)
 497                 return -EFAULT;
 498
 499         err = be32_to_cpu(cmd->header.out.return_code);
 500         if (err != 0)
 501                 dev_err(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
 502
 503         return err;
 504 }
 505
 506 /**
 507  * tpm_continue_selftest -- run TPM's selftest
 508  * @chip: TPM chip to use
 509  *
 510  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
 511  * a TPM error code.
 512  */
 513 int tpm_continue_selftest(struct tpm_chip *chip)
 514 {
 515         int rc;
 516         struct tpm_cmd_t cmd;
 517
 518         cmd.header.in = continue_selftest_header;
 519         rc = transmit_cmd(chip, (const u8 *) &cmd,
 520                           CONTINUE_SELFTEST_RESULT_SIZE, "continue selftest");
 521         return rc;
 522 }
 523 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
 524
 525 /*
 526  * Returns max number of jiffies to wait
 527  */
 528 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
 529                                            u32 ordinal)
 530 {
 531         int duration_idx = TPM_UNDEFINED;
 532         int duration = 0;
 533
 534         if (ordinal < TPM_MAX_ORDINAL)
 535                 duration_idx = tpm_ordinal_duration[ordinal];
 536         else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
 537                  TPM_MAX_PROTECTED_ORDINAL)
 538                 duration_idx =
 539                     tpm_protected_ordinal_duration[ordinal &
 540                                                    TPM_PROTECTED_ORDINAL_MASK];
 541
 542         if (duration_idx != TPM_UNDEFINED)
 543                 duration = chip->vendor.duration[duration_idx];
 544         if (duration <= 0)
 545                 return 2 * 60 * HZ;
 546         else
 547                 return duration;
 548 }
 549 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 550
 551 #define TPM_DIGEST_SIZE 20
 552 #define TPM_RET_CODE_IDX 6
 553
 554 enum tpm_capabilities {
 555         TPM_CAP_FLAG = cpu_to_be32(4),
 556         TPM_CAP_PROP = cpu_to_be32(5),
 557         CAP_VERSION_1_1 = cpu_to_be32(0x06),
 558         CAP_VERSION_1_2 = cpu_to_be32(0x1A)
 559 };
 560
 561 enum tpm_sub_capabilities {
 562         TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
 563         TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
 564         TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
 565         TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
 566         TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
 567         TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
 568         TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
 569
 570 };
 571
 572 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
 573                    const char *desc)
 574 {
 575         struct tpm_cmd_t tpm_cmd;
 576         int rc;
 577         struct tpm_chip *chip = dev_get_drvdata(dev);
 578
 579         tpm_cmd.header.in = tpm_getcap_header;
 580         if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
 581                 tpm_cmd.params.getcap_in.cap = subcap_id;
 582                 /*subcap field not necessary */
 583                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
 584                 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
 585         } else {
 586                 if (subcap_id == TPM_CAP_FLAG_PERM ||
 587                     subcap_id == TPM_CAP_FLAG_VOL)
 588                         tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
 589                 else
 590                         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 591                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 592                 tpm_cmd.params.getcap_in.subcap = subcap_id;
 593         }
 594         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
 595         if (!rc)
 596                 *cap = tpm_cmd.params.getcap_out.cap;
 597         return rc;
 598 }
 599
 600 void tpm_gen_interrupt(struct tpm_chip *chip)
 601 {
 602         struct  tpm_cmd_t tpm_cmd;
 603         ssize_t rc;
 604
 605         tpm_cmd.header.in = tpm_getcap_header;
 606         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 607         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 608         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 609
 610         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 611                         "attempting to determine the timeouts");
 612 }
 613 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
 614
 615 int tpm_get_timeouts(struct tpm_chip *chip)
 616 {
 617         struct tpm_cmd_t tpm_cmd;
 618         struct timeout_t *timeout_cap;
 619         struct duration_t *duration_cap;
 620         ssize_t rc;
 621         u32 timeout;
 622         unsigned int scale = 1;
 623
 624         tpm_cmd.header.in = tpm_getcap_header;
 625         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 626         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 627         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 628
 629         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 630                         "attempting to determine the timeouts");
 631         if (rc)
 632                 goto duration;
 633
 634         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 635             be32_to_cpu(tpm_cmd.header.out.length)
 636             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
 637                 return -EINVAL;
 638
 639         timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
 640         /* Don't overwrite default if value is 0 */
 641         timeout = be32_to_cpu(timeout_cap->a);
 642         if (timeout && timeout < 1000) {
 643                 /* timeouts in msec rather usec */
 644                 scale = 1000;
 645                 chip->vendor.timeout_adjusted = true;
 646         }
 647         if (timeout)
 648                 chip->vendor.timeout_a = usecs_to_jiffies(timeout * scale);
 649         timeout = be32_to_cpu(timeout_cap->b);
 650         if (timeout)
 651                 chip->vendor.timeout_b = usecs_to_jiffies(timeout * scale);
 652         timeout = be32_to_cpu(timeout_cap->c);
 653         if (timeout)
 654                 chip->vendor.timeout_c = usecs_to_jiffies(timeout * scale);
 655         timeout = be32_to_cpu(timeout_cap->d);
 656         if (timeout)
 657                 chip->vendor.timeout_d = usecs_to_jiffies(timeout * scale);
 658
 659 duration:
 660         tpm_cmd.header.in = tpm_getcap_header;
 661         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 662         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 663         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
 664
 665         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 666                         "attempting to determine the durations");
 667         if (rc)
 668                 return rc;
 669
 670         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 671             be32_to_cpu(tpm_cmd.header.out.length)
 672             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
 673                 return -EINVAL;
 674
 675         duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
 676         chip->vendor.duration[TPM_SHORT] =
 677             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
 678         chip->vendor.duration[TPM_MEDIUM] =
 679             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
 680         chip->vendor.duration[TPM_LONG] =
 681             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
 682
 683         /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
 684          * value wrong and apparently reports msecs rather than usecs. So we
 685          * fix up the resulting too-small TPM_SHORT value to make things work.
 686          * We also scale the TPM_MEDIUM and -_LONG values by 1000.
 687          */
 688         if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
 689                 chip->vendor.duration[TPM_SHORT] = HZ;
 690                 chip->vendor.duration[TPM_MEDIUM] *= 1000;
 691                 chip->vendor.duration[TPM_LONG] *= 1000;
 692                 chip->vendor.duration_adjusted = true;
 693                 dev_info(chip->dev, "Adjusting TPM timeout parameters.");
 694         }
 695         return 0;
 696 }
 697 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
 698
 699 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
 700                         char *buf)
 701 {
 702         cap_t cap;
 703         ssize_t rc;
 704
 705         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 706                          "attempting to determine the permanent enabled state");
 707         if (rc)
 708                 return 0;
 709
 710         rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
 711         return rc;
 712 }
 713 EXPORT_SYMBOL_GPL(tpm_show_enabled);
 714
 715 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
 716                         char *buf)
 717 {
 718         cap_t cap;
 719         ssize_t rc;
 720
 721         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 722                          "attempting to determine the permanent active state");
 723         if (rc)
 724                 return 0;
 725
 726         rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
 727         return rc;
 728 }
 729 EXPORT_SYMBOL_GPL(tpm_show_active);
 730
 731 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
 732                         char *buf)
 733 {
 734         cap_t cap;
 735         ssize_t rc;
 736
 737         rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
 738                          "attempting to determine the owner state");
 739         if (rc)
 740                 return 0;
 741
 742         rc = sprintf(buf, "%d\n", cap.owned);
 743         return rc;
 744 }
 745 EXPORT_SYMBOL_GPL(tpm_show_owned);
 746
 747 ssize_t tpm_show_temp_deactivated(struct device * dev,
 748                                 struct device_attribute * attr, char *buf)
 749 {
 750         cap_t cap;
 751         ssize_t rc;
 752
 753         rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
 754                          "attempting to determine the temporary state");
 755         if (rc)
 756                 return 0;
 757
 758         rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
 759         return rc;
 760 }
 761 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
 762
 763 /*
 764  * tpm_chip_find_get - return tpm_chip for given chip number
 765  */
 766 static struct tpm_chip *tpm_chip_find_get(int chip_num)
 767 {
 768         struct tpm_chip *pos, *chip = NULL;
 769
 770         rcu_read_lock();
 771         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
 772                 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
 773                         continue;
 774
 775                 if (try_module_get(pos->dev->driver->owner)) {
 776                         chip = pos;
 777                         break;
 778                 }
 779         }
 780         rcu_read_unlock();
 781         return chip;
 782 }
 783
 784 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
 785 #define READ_PCR_RESULT_SIZE 30
 786 static struct tpm_input_header pcrread_header = {
 787         .tag = TPM_TAG_RQU_COMMAND,
 788         .length = cpu_to_be32(14),
 789         .ordinal = TPM_ORDINAL_PCRREAD
 790 };
 791
 792 static int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 793 {
 794         int rc;
 795         struct tpm_cmd_t cmd;
 796
 797         cmd.header.in = pcrread_header;
 798         cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
 799         rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
 800                           "attempting to read a pcr value");
 801
 802         if (rc == 0)
 803                 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
 804                        TPM_DIGEST_SIZE);
 805         return rc;
 806 }
 807
 808 /**
 809  * tpm_pcr_read - read a pcr value
 810  * @chip_num:   tpm idx # or ANY
 811  * @pcr_idx:    pcr idx to retrieve
 812  * @res_buf:    TPM_PCR value
 813  *              size of res_buf is 20 bytes (or NULL if you don't care)
 814  *
 815  * The TPM driver should be built-in, but for whatever reason it
 816  * isn't, protect against the chip disappearing, by incrementing
 817  * the module usage count.
 818  */
 819 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
 820 {
 821         struct tpm_chip *chip;
 822         int rc;
 823
 824         chip = tpm_chip_find_get(chip_num);
 825         if (chip == NULL)
 826                 return -ENODEV;
 827         rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
 828         tpm_chip_put(chip);
 829         return rc;
 830 }
 831 EXPORT_SYMBOL_GPL(tpm_pcr_read);
 832
 833 /**
 834  * tpm_pcr_extend - extend pcr value with hash
 835  * @chip_num:   tpm idx # or AN&
 836  * @pcr_idx:    pcr idx to extend
 837  * @hash:       hash value used to extend pcr value
 838  *
 839  * The TPM driver should be built-in, but for whatever reason it
 840  * isn't, protect against the chip disappearing, by incrementing
 841  * the module usage count.
 842  */
 843 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
 844 #define EXTEND_PCR_RESULT_SIZE 34
 845 static struct tpm_input_header pcrextend_header = {
 846         .tag = TPM_TAG_RQU_COMMAND,
 847         .length = cpu_to_be32(34),
 848         .ordinal = TPM_ORD_PCR_EXTEND
 849 };
 850
 851 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
 852 {
 853         struct tpm_cmd_t cmd;
 854         int rc;
 855         struct tpm_chip *chip;
 856
 857         chip = tpm_chip_find_get(chip_num);
 858         if (chip == NULL)
 859                 return -ENODEV;
 860
 861         cmd.header.in = pcrextend_header;
 862         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
 863         memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
 864         rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
 865                           "attempting extend a PCR value");
 866
 867         tpm_chip_put(chip);
 868         return rc;
 869 }
 870 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
 871
 872 /**
 873  * tpm_do_selftest - have the TPM continue its selftest and wait until it
 874  *                   can receive further commands
 875  * @chip: TPM chip to use
 876  *
 877  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
 878  * a TPM error code.
 879  */
 880 int tpm_do_selftest(struct tpm_chip *chip)
 881 {
 882         int rc;
 883         u8 digest[TPM_DIGEST_SIZE];
 884         unsigned int loops;
 885         unsigned int delay_msec = 1000;
 886         unsigned long duration;
 887
 888         duration = tpm_calc_ordinal_duration(chip,
 889                                              TPM_ORD_CONTINUE_SELFTEST);
 890
 891         loops = jiffies_to_msecs(duration) / delay_msec;
 892
 893         rc = tpm_continue_selftest(chip);
 894         /* This may fail if there was no TPM driver during a suspend/resume
 895          * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
 896          */
 897         if (rc)
 898                 return rc;
 899
 900         do {
 901                 rc = __tpm_pcr_read(chip, 0, digest);
 902                 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
 903                         dev_info(chip->dev,
 904                                  "TPM is disabled/deactivated (0x%X)\n", rc);
 905                         /* TPM is disabled and/or deactivated; driver can
 906                          * proceed and TPM does handle commands for
 907                          * suspend/resume correctly
 908                          */
 909                         return 0;
 910                 }
 911                 if (rc != TPM_WARN_DOING_SELFTEST)
 912                         return rc;
 913                 msleep(delay_msec);
 914         } while (--loops > 0);
 915
 916         return rc;
 917 }
 918 EXPORT_SYMBOL_GPL(tpm_do_selftest);
 919
 920 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
 921 {
 922         struct tpm_chip *chip;
 923         int rc;
 924
 925         chip = tpm_chip_find_get(chip_num);
 926         if (chip == NULL)
 927                 return -ENODEV;
 928
 929         rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
 930
 931         tpm_chip_put(chip);
 932         return rc;
 933 }
 934 EXPORT_SYMBOL_GPL(tpm_send);
 935
 936 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
 937                       char *buf)
 938 {
 939         cap_t cap;
 940         u8 digest[TPM_DIGEST_SIZE];
 941         ssize_t rc;
 942         int i, j, num_pcrs;
 943         char *str = buf;
 944         struct tpm_chip *chip = dev_get_drvdata(dev);
 945
 946         rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
 947                         "attempting to determine the number of PCRS");
 948         if (rc)
 949                 return 0;
 950
 951         num_pcrs = be32_to_cpu(cap.num_pcrs);
 952         for (i = 0; i < num_pcrs; i++) {
 953                 rc = __tpm_pcr_read(chip, i, digest);
 954                 if (rc)
 955                         break;
 956                 str += sprintf(str, "PCR-%02d: ", i);
 957                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
 958                         str += sprintf(str, "%02X ", digest[j]);
 959                 str += sprintf(str, "\n");
 960         }
 961         return str - buf;
 962 }
 963 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 964
 965 #define  READ_PUBEK_RESULT_SIZE 314
 966 #define TPM_ORD_READPUBEK cpu_to_be32(124)
 967 struct tpm_input_header tpm_readpubek_header = {
 968         .tag = TPM_TAG_RQU_COMMAND,
 969         .length = cpu_to_be32(30),
 970         .ordinal = TPM_ORD_READPUBEK
 971 };
 972
 973 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
 974                        char *buf)
 975 {
 976         u8 *data;
 977         struct tpm_cmd_t tpm_cmd;
 978         ssize_t err;
 979         int i, rc;
 980         char *str = buf;
 981
 982         struct tpm_chip *chip = dev_get_drvdata(dev);
 983
 984         tpm_cmd.header.in = tpm_readpubek_header;
 985         err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
 986                         "attempting to read the PUBEK");
 987         if (err)
 988                 goto out;
 989
 990         /*
 991            ignore header 10 bytes
 992            algorithm 32 bits (1 == RSA )
 993            encscheme 16 bits
 994            sigscheme 16 bits
 995            parameters (RSA 12->bytes: keybit, #primes, expbit)
 996            keylenbytes 32 bits
 997            256 byte modulus
 998            ignore checksum 20 bytes
 999          */
1000         data = tpm_cmd.params.readpubek_out_buffer;
1001         str +=
1002             sprintf(str,
1003                     "Algorithm: %02X %02X %02X %02X\n"
1004                     "Encscheme: %02X %02X\n"
1005                     "Sigscheme: %02X %02X\n"
1006                     "Parameters: %02X %02X %02X %02X "
1007                     "%02X %02X %02X %02X "
1008                     "%02X %02X %02X %02X\n"
1009                     "Modulus length: %d\n"
1010                     "Modulus:\n",
1011                     data[0], data[1], data[2], data[3],
1012                     data[4], data[5],
1013                     data[6], data[7],
1014                     data[12], data[13], data[14], data[15],
1015                     data[16], data[17], data[18], data[19],
1016                     data[20], data[21], data[22], data[23],
1017                     be32_to_cpu(*((__be32 *) (data + 24))));
1018
1019         for (i = 0; i < 256; i++) {
1020                 str += sprintf(str, "%02X ", data[i + 28]);
1021                 if ((i + 1) % 16 == 0)
1022                         str += sprintf(str, "\n");
1023         }
1024 out:
1025         rc = str - buf;
1026         return rc;
1027 }
1028 EXPORT_SYMBOL_GPL(tpm_show_pubek);
1029
1030
1031 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
1032                       char *buf)
1033 {
1034         cap_t cap;
1035         ssize_t rc;
1036         char *str = buf;
1037
1038         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
1039                         "attempting to determine the manufacturer");
1040         if (rc)
1041                 return 0;
1042         str += sprintf(str, "Manufacturer: 0x%x\n",
1043                        be32_to_cpu(cap.manufacturer_id));
1044
1045         rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
1046                         "attempting to determine the 1.1 version");
1047         if (rc)
1048                 return 0;
1049         str += sprintf(str,
1050                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
1051                        cap.tpm_version.Major, cap.tpm_version.Minor,
1052                        cap.tpm_version.revMajor, cap.tpm_version.revMinor);
1053         return str - buf;
1054 }
1055 EXPORT_SYMBOL_GPL(tpm_show_caps);
1056
1057 ssize_t tpm_show_caps_1_2(struct device * dev,
1058                           struct device_attribute * attr, char *buf)
1059 {
1060         cap_t cap;
1061         ssize_t rc;
1062         char *str = buf;
1063
1064         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
1065                         "attempting to determine the manufacturer");
1066         if (rc)
1067                 return 0;
1068         str += sprintf(str, "Manufacturer: 0x%x\n",
1069                        be32_to_cpu(cap.manufacturer_id));
1070         rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
1071                          "attempting to determine the 1.2 version");
1072         if (rc)
1073                 return 0;
1074         str += sprintf(str,
1075                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
1076                        cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
1077                        cap.tpm_version_1_2.revMajor,
1078                        cap.tpm_version_1_2.revMinor);
1079         return str - buf;
1080 }
1081 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
1082
1083 ssize_t tpm_show_durations(struct device *dev, struct device_attribute *attr,
1084                           char *buf)
1085 {
1086         struct tpm_chip *chip = dev_get_drvdata(dev);
1087
1088         if (chip->vendor.duration[TPM_LONG] == 0)
1089                 return 0;
1090
1091         return sprintf(buf, "%d %d %d [%s]\n",
1092                        jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
1093                        jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
1094                        jiffies_to_usecs(chip->vendor.duration[TPM_LONG]),
1095                        chip->vendor.duration_adjusted
1096                        ? "adjusted" : "original");
1097 }
1098 EXPORT_SYMBOL_GPL(tpm_show_durations);
1099
1100 ssize_t tpm_show_timeouts(struct device *dev, struct device_attribute *attr,
1101                           char *buf)
1102 {
1103         struct tpm_chip *chip = dev_get_drvdata(dev);
1104
1105         return sprintf(buf, "%d %d %d %d [%s]\n",
1106                        jiffies_to_usecs(chip->vendor.timeout_a),
1107                        jiffies_to_usecs(chip->vendor.timeout_b),
1108                        jiffies_to_usecs(chip->vendor.timeout_c),
1109                        jiffies_to_usecs(chip->vendor.timeout_d),
1110                        chip->vendor.timeout_adjusted
1111                        ? "adjusted" : "original");
1112 }
1113 EXPORT_SYMBOL_GPL(tpm_show_timeouts);
1114
1115 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
1116                         const char *buf, size_t count)
1117 {
1118         struct tpm_chip *chip = dev_get_drvdata(dev);
1119         if (chip == NULL)
1120                 return 0;
1121
1122         chip->vendor.cancel(chip);
1123         return count;
1124 }
1125 EXPORT_SYMBOL_GPL(tpm_store_cancel);
1126
1127 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
1128                          wait_queue_head_t *queue)
1129 {
1130         unsigned long stop;
1131         long rc;
1132         u8 status;
1133
1134         /* check current status */
1135         status = chip->vendor.status(chip);
1136         if ((status & mask) == mask)
1137                 return 0;
1138
1139         stop = jiffies + timeout;
1140
1141         if (chip->vendor.irq) {
1142 again:
1143                 timeout = stop - jiffies;
1144                 if ((long)timeout <= 0)
1145                         return -ETIME;
1146                 rc = wait_event_interruptible_timeout(*queue,
1147                                                       ((chip->vendor.status(chip)
1148                                                       & mask) == mask),
1149                                                       timeout);
1150                 if (rc > 0)
1151                         return 0;
1152                 if (rc == -ERESTARTSYS && freezing(current)) {
1153                         clear_thread_flag(TIF_SIGPENDING);
1154                         goto again;
1155                 }
1156         } else {
1157                 do {
1158                         msleep(TPM_TIMEOUT);
1159                         status = chip->vendor.status(chip);
1160                         if ((status & mask) == mask)
1161                                 return 0;
1162                 } while (time_before(jiffies, stop));
1163         }
1164         return -ETIME;
1165 }
1166 EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
1167 /*
1168  * Device file system interface to the TPM
1169  *
1170  * It's assured that the chip will be opened just once,
1171  * by the check of is_open variable, which is protected
1172  * by driver_lock.
1173  */
1174 int tpm_open(struct inode *inode, struct file *file)
1175 {
1176         int minor = iminor(inode);
1177         struct tpm_chip *chip = NULL, *pos;
1178
1179         rcu_read_lock();
1180         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
1181                 if (pos->vendor.miscdev.minor == minor) {
1182                         chip = pos;
1183                         get_device(chip->dev);
1184                         break;
1185                 }
1186         }
1187         rcu_read_unlock();
1188
1189         if (!chip)
1190                 return -ENODEV;
1191
1192         if (test_and_set_bit(0, &chip->is_open)) {
1193                 dev_dbg(chip->dev, "Another process owns this TPM\n");
1194                 put_device(chip->dev);
1195                 return -EBUSY;
1196         }
1197
1198         chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
1199         if (chip->data_buffer == NULL) {
1200                 clear_bit(0, &chip->is_open);
1201                 put_device(chip->dev);
1202                 return -ENOMEM;
1203         }
1204
1205         atomic_set(&chip->data_pending, 0);
1206
1207         file->private_data = chip;
1208         return 0;
1209 }
1210 EXPORT_SYMBOL_GPL(tpm_open);
1211
1212 /*
1213  * Called on file close
1214  */
1215 int tpm_release(struct inode *inode, struct file *file)
1216 {
1217         struct tpm_chip *chip = file->private_data;
1218
1219         del_singleshot_timer_sync(&chip->user_read_timer);
1220         flush_work_sync(&chip->work);
1221         file->private_data = NULL;
1222         atomic_set(&chip->data_pending, 0);
1223         kfree(chip->data_buffer);
1224         clear_bit(0, &chip->is_open);
1225         put_device(chip->dev);
1226         return 0;
1227 }
1228 EXPORT_SYMBOL_GPL(tpm_release);
1229
1230 ssize_t tpm_write(struct file *file, const char __user *buf,
1231                   size_t size, loff_t *off)
1232 {
1233         struct tpm_chip *chip = file->private_data;
1234         size_t in_size = size, out_size;
1235
1236         /* cannot perform a write until the read has cleared
1237            either via tpm_read or a user_read_timer timeout */
1238         while (atomic_read(&chip->data_pending) != 0)
1239                 msleep(TPM_TIMEOUT);
1240
1241         resume_if_needed(chip);
1242
1243         mutex_lock(&chip->buffer_mutex);
1244
1245         if (in_size > TPM_BUFSIZE)
1246                 in_size = TPM_BUFSIZE;
1247
1248         if (copy_from_user
1249             (chip->data_buffer, (void __user *) buf, in_size)) {
1250                 mutex_unlock(&chip->buffer_mutex);
1251                 return -EFAULT;
1252         }
1253
1254         /* atomic tpm command send and result receive */
1255         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1256
1257         atomic_set(&chip->data_pending, out_size);
1258         mutex_unlock(&chip->buffer_mutex);
1259
1260         /* Set a timeout by which the reader must come claim the result */
1261         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1262
1263         return in_size;
1264 }
1265 EXPORT_SYMBOL_GPL(tpm_write);
1266
1267 ssize_t tpm_read(struct file *file, char __user *buf,
1268                  size_t size, loff_t *off)
1269 {
1270         struct tpm_chip *chip = file->private_data;
1271         ssize_t ret_size;
1272         int rc;
1273
1274         del_singleshot_timer_sync(&chip->user_read_timer);
1275         flush_work_sync(&chip->work);
1276         ret_size = atomic_read(&chip->data_pending);
1277         /* TODO(wad): atomic_set should come AFTER the buffer is copied. */
1278         atomic_set(&chip->data_pending, 0);
1279         if (ret_size > 0) {     /* relay data */
1280                 ssize_t orig_ret_size = ret_size;
1281                 if (size < ret_size)
1282                         ret_size = size;
1283
1284                 mutex_lock(&chip->buffer_mutex);
1285                 rc = copy_to_user(buf, chip->data_buffer, ret_size);
1286                 memset(chip->data_buffer, 0, orig_ret_size);
1287                 if (rc)
1288                         ret_size = -EFAULT;
1289
1290                 mutex_unlock(&chip->buffer_mutex);
1291         }
1292
1293         return ret_size;
1294 }
1295 EXPORT_SYMBOL_GPL(tpm_read);
1296
1297 void tpm_remove_hardware(struct device *dev)
1298 {
1299         struct tpm_chip *chip = dev_get_drvdata(dev);
1300
1301         if (chip == NULL) {
1302                 dev_err(dev, "No device data found\n");
1303                 return;
1304         }
1305
1306         spin_lock(&driver_lock);
1307         list_del_rcu(&chip->list);
1308         spin_unlock(&driver_lock);
1309         synchronize_rcu();
1310
1311         misc_deregister(&chip->vendor.miscdev);
1312         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1313         tpm_bios_log_teardown(chip->bios_dir);
1314
1315         /* write it this way to be explicit (chip->dev == dev) */
1316         put_device(chip->dev);
1317 }
1318 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1319
1320 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1321 #define SAVESTATE_RESULT_SIZE 10
1322
1323 static struct tpm_input_header savestate_header = {
1324         .tag = TPM_TAG_RQU_COMMAND,
1325         .length = cpu_to_be32(10),
1326         .ordinal = TPM_ORD_SAVESTATE
1327 };
1328
1329 /*
1330  * We are about to suspend. Save the TPM state
1331  * so that it can be restored.
1332  */
1333 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1334 {
1335         struct tpm_chip *chip = dev_get_drvdata(dev);
1336         struct tpm_cmd_t cmd;
1337         int rc;
1338
1339         u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1340
1341         if (chip == NULL)
1342                 return -ENODEV;
1343
1344         /* for buggy tpm, flush pcrs with extend to selected dummy */
1345         if (tpm_suspend_pcr) {
1346                 cmd.header.in = pcrextend_header;
1347                 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1348                 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1349                        TPM_DIGEST_SIZE);
1350                 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1351                                   "extending dummy pcr before suspend");
1352         }
1353
1354         /* now do the actual savestate */
1355         cmd.header.in = savestate_header;
1356         rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE,
1357                           "sending savestate before suspend");
1358         return rc;
1359 }
1360 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1361
1362 /*
1363  * Resume from a power safe. The BIOS already restored
1364  * the TPM state.
1365  */
1366 int tpm_pm_resume(struct device *dev)
1367 {
1368         struct tpm_chip *chip = dev_get_drvdata(dev);
1369
1370         if (chip == NULL)
1371                 return -ENODEV;
1372
1373         set_needs_resume(chip);
1374         return 0;
1375 }
1376 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1377
1378 /* In case vendor provided release function, call it too.*/
1379
1380 void tpm_dev_vendor_release(struct tpm_chip *chip)
1381 {
1382         if (chip->vendor.release)
1383                 chip->vendor.release(chip->dev);
1384
1385         clear_bit(chip->dev_num, dev_mask);
1386         kfree(chip->vendor.miscdev.name);
1387 }
1388 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1389
1390
1391 /*
1392  * Once all references to platform device are down to 0,
1393  * release all allocated structures.
1394  */
1395 void tpm_dev_release(struct device *dev)
1396 {
1397         struct tpm_chip *chip = dev_get_drvdata(dev);
1398
1399         tpm_dev_vendor_release(chip);
1400
1401         chip->release(dev);
1402         kfree(chip);
1403 }
1404 EXPORT_SYMBOL_GPL(tpm_dev_release);
1405
1406 /*
1407  * Called from tpm_<specific>.c probe function only for devices
1408  * the driver has determined it should claim.  Prior to calling
1409  * this function the specific probe function has called pci_enable_device
1410  * upon errant exit from this function specific probe function should call
1411  * pci_disable_device
1412  */
1413 struct tpm_chip *tpm_register_hardware(struct device *dev,
1414                                         const struct tpm_vendor_specific *entry)
1415 {
1416 #define DEVNAME_SIZE 7
1417
1418         char *devname;
1419         struct tpm_chip *chip;
1420
1421         /* Driver specific per-device data */
1422         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1423         devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1424
1425         if (chip == NULL || devname == NULL)
1426                 goto out_free;
1427
1428         mutex_init(&chip->buffer_mutex);
1429         mutex_init(&chip->tpm_mutex);
1430         mutex_init(&chip->resume_mutex);
1431         INIT_LIST_HEAD(&chip->list);
1432
1433         INIT_WORK(&chip->work, timeout_work);
1434
1435         setup_timer(&chip->user_read_timer, user_reader_timeout,
1436                         (unsigned long)chip);
1437
1438         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1439
1440         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1441
1442         if (chip->dev_num >= TPM_NUM_DEVICES) {
1443                 dev_err(dev, "No available tpm device numbers\n");
1444                 goto out_free;
1445         } else if (chip->dev_num == 0)
1446                 chip->vendor.miscdev.minor = TPM_MINOR;
1447         else
1448                 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1449
1450         set_bit(chip->dev_num, dev_mask);
1451
1452         scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1453         chip->vendor.miscdev.name = devname;
1454
1455         chip->vendor.miscdev.parent = dev;
1456         chip->dev = get_device(dev);
1457         chip->release = dev->release;
1458         dev->release = tpm_dev_release;
1459         dev_set_drvdata(dev, chip);
1460
1461         if (misc_register(&chip->vendor.miscdev)) {
1462                 dev_err(chip->dev,
1463                         "unable to misc_register %s, minor %d\n",
1464                         chip->vendor.miscdev.name,
1465                         chip->vendor.miscdev.minor);
1466                 put_device(chip->dev);
1467                 return NULL;
1468         }
1469
1470         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1471                 misc_deregister(&chip->vendor.miscdev);
1472                 put_device(chip->dev);
1473
1474                 return NULL;
1475         }
1476
1477         chip->bios_dir = tpm_bios_log_setup(devname);
1478
1479         /* Make chip available */
1480         spin_lock(&driver_lock);
1481         list_add_rcu(&chip->list, &tpm_chip_list);
1482         spin_unlock(&driver_lock);
1483
1484         return chip;
1485
1486 out_free:
1487         kfree(chip);
1488         kfree(devname);
1489         return NULL;
1490 }
1491 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1492
1493 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1494 MODULE_DESCRIPTION("TPM Driver");
1495 MODULE_VERSION("2.0");
1496 MODULE_LICENSE("GPL");