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