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 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 /**
 446  * tpm_continue_selftest -- run TPM's selftest
 447  * @chip: TPM chip to use
 448  *
 449  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
 450  * a TPM error code.
 451  */
 452 int tpm_continue_selftest(struct tpm_chip *chip)
 453 {
 454         int rc;
 455         struct tpm_cmd_t cmd;
 456
 457         cmd.header.in = continue_selftest_header;
 458         rc = tpm_transmit(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE);
 459         return rc;
 460 }
 461 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
 462
 463 /* The maximum time in milliseconds that the TPM self test will take to
 464  * complete.  TODO(semenzato): 1s should be plenty for all TPMs, but how can we
 465  * ensure it?
 466  */
 467 #define TPM_SELF_TEST_DURATION_MSEC 1000
 468
 469 static void resume_if_needed(struct tpm_chip *chip)
 470 {
 471         mutex_lock(&chip->resume_mutex);
 472         if (chip->needs_resume) {
 473                 /* If it's been TPM_SELF_TEST_DURATION_MSEC msec since resume,
 474                  * then selftest has completed and we don't need to wait.
 475                  */
 476                 if (jiffies - chip->resume_time <
 477                     msecs_to_jiffies(TPM_SELF_TEST_DURATION_MSEC)) {
 478                         dev_info(chip->dev, "waiting for TPM self test");
 479                         tpm_continue_selftest(chip);
 480                 }
 481                 chip->needs_resume = 0;
 482                 dev_info(chip->dev, "TPM delayed resume completed");
 483         }
 484         mutex_unlock(&chip->resume_mutex);
 485 }
 486
 487 static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
 488                             int len, const char *desc)
 489 {
 490         int err;
 491
 492         resume_if_needed(chip);
 493
 494         len = tpm_transmit(chip,(u8 *) cmd, len);
 495         if (len <  0)
 496                 return len;
 497         else if (len < TPM_HEADER_SIZE)
 498                 return -EFAULT;
 499
 500         err = be32_to_cpu(cmd->header.out.return_code);
 501         if (err != 0)
 502                 dev_err(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
 503
 504         return err;
 505 }
 506
 507 /*
 508  * Returns max number of jiffies to wait
 509  */
 510 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
 511                                            u32 ordinal)
 512 {
 513         int duration_idx = TPM_UNDEFINED;
 514         int duration = 0;
 515
 516         if (ordinal < TPM_MAX_ORDINAL)
 517                 duration_idx = tpm_ordinal_duration[ordinal];
 518         else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
 519                  TPM_MAX_PROTECTED_ORDINAL)
 520                 duration_idx =
 521                     tpm_protected_ordinal_duration[ordinal &
 522                                                    TPM_PROTECTED_ORDINAL_MASK];
 523
 524         if (duration_idx != TPM_UNDEFINED)
 525                 duration = chip->vendor.duration[duration_idx];
 526         if (duration <= 0)
 527                 return 2 * 60 * HZ;
 528         else
 529                 return duration;
 530 }
 531 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 532
 533 #define TPM_DIGEST_SIZE 20
 534 #define TPM_RET_CODE_IDX 6
 535
 536 enum tpm_capabilities {
 537         TPM_CAP_FLAG = cpu_to_be32(4),
 538         TPM_CAP_PROP = cpu_to_be32(5),
 539         CAP_VERSION_1_1 = cpu_to_be32(0x06),
 540         CAP_VERSION_1_2 = cpu_to_be32(0x1A)
 541 };
 542
 543 enum tpm_sub_capabilities {
 544         TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
 545         TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
 546         TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
 547         TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
 548         TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
 549         TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
 550         TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
 551
 552 };
 553
 554 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
 555                    const char *desc)
 556 {
 557         struct tpm_cmd_t tpm_cmd;
 558         int rc;
 559         struct tpm_chip *chip = dev_get_drvdata(dev);
 560
 561         tpm_cmd.header.in = tpm_getcap_header;
 562         if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
 563                 tpm_cmd.params.getcap_in.cap = subcap_id;
 564                 /*subcap field not necessary */
 565                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
 566                 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
 567         } else {
 568                 if (subcap_id == TPM_CAP_FLAG_PERM ||
 569                     subcap_id == TPM_CAP_FLAG_VOL)
 570                         tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
 571                 else
 572                         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 573                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 574                 tpm_cmd.params.getcap_in.subcap = subcap_id;
 575         }
 576         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
 577         if (!rc)
 578                 *cap = tpm_cmd.params.getcap_out.cap;
 579         return rc;
 580 }
 581
 582 void tpm_gen_interrupt(struct tpm_chip *chip)
 583 {
 584         struct  tpm_cmd_t tpm_cmd;
 585         ssize_t rc;
 586
 587         tpm_cmd.header.in = tpm_getcap_header;
 588         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 589         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 590         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 591
 592         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 593                         "attempting to determine the timeouts");
 594 }
 595 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
 596
 597 int tpm_get_timeouts(struct tpm_chip *chip)
 598 {
 599         struct tpm_cmd_t tpm_cmd;
 600         struct timeout_t *timeout_cap;
 601         struct duration_t *duration_cap;
 602         ssize_t rc;
 603         u32 timeout;
 604         unsigned int scale = 1;
 605
 606         tpm_cmd.header.in = tpm_getcap_header;
 607         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 608         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 609         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 610
 611         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 612                         "attempting to determine the timeouts");
 613         if (rc)
 614                 goto duration;
 615
 616         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 617             be32_to_cpu(tpm_cmd.header.out.length)
 618             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
 619                 return -EINVAL;
 620
 621         timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
 622         /* Don't overwrite default if value is 0 */
 623         timeout = be32_to_cpu(timeout_cap->a);
 624         if (timeout && timeout < 1000) {
 625                 /* timeouts in msec rather usec */
 626                 scale = 1000;
 627                 chip->vendor.timeout_adjusted = true;
 628         }
 629         if (timeout)
 630                 chip->vendor.timeout_a = usecs_to_jiffies(timeout * scale);
 631         timeout = be32_to_cpu(timeout_cap->b);
 632         if (timeout)
 633                 chip->vendor.timeout_b = usecs_to_jiffies(timeout * scale);
 634         timeout = be32_to_cpu(timeout_cap->c);
 635         if (timeout)
 636                 chip->vendor.timeout_c = usecs_to_jiffies(timeout * scale);
 637         timeout = be32_to_cpu(timeout_cap->d);
 638         if (timeout)
 639                 chip->vendor.timeout_d = usecs_to_jiffies(timeout * scale);
 640
 641 duration:
 642         tpm_cmd.header.in = tpm_getcap_header;
 643         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 644         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 645         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
 646
 647         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 648                         "attempting to determine the durations");
 649         if (rc)
 650                 return rc;
 651
 652         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 653             be32_to_cpu(tpm_cmd.header.out.length)
 654             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
 655                 return -EINVAL;
 656
 657         duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
 658         chip->vendor.duration[TPM_SHORT] =
 659             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
 660         chip->vendor.duration[TPM_MEDIUM] =
 661             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
 662         chip->vendor.duration[TPM_LONG] =
 663             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
 664
 665         /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
 666          * value wrong and apparently reports msecs rather than usecs. So we
 667          * fix up the resulting too-small TPM_SHORT value to make things work.
 668          * We also scale the TPM_MEDIUM and -_LONG values by 1000.
 669          */
 670         if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
 671                 chip->vendor.duration[TPM_SHORT] = HZ;
 672                 chip->vendor.duration[TPM_MEDIUM] *= 1000;
 673                 chip->vendor.duration[TPM_LONG] *= 1000;
 674                 chip->vendor.duration_adjusted = true;
 675                 dev_info(chip->dev, "Adjusting TPM timeout parameters.");
 676         }
 677         return 0;
 678 }
 679 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
 680
 681 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
 682                         char *buf)
 683 {
 684         cap_t cap;
 685         ssize_t rc;
 686
 687         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 688                          "attempting to determine the permanent enabled state");
 689         if (rc)
 690                 return 0;
 691
 692         rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
 693         return rc;
 694 }
 695 EXPORT_SYMBOL_GPL(tpm_show_enabled);
 696
 697 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
 698                         char *buf)
 699 {
 700         cap_t cap;
 701         ssize_t rc;
 702
 703         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 704                          "attempting to determine the permanent active state");
 705         if (rc)
 706                 return 0;
 707
 708         rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
 709         return rc;
 710 }
 711 EXPORT_SYMBOL_GPL(tpm_show_active);
 712
 713 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
 714                         char *buf)
 715 {
 716         cap_t cap;
 717         ssize_t rc;
 718
 719         rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
 720                          "attempting to determine the owner state");
 721         if (rc)
 722                 return 0;
 723
 724         rc = sprintf(buf, "%d\n", cap.owned);
 725         return rc;
 726 }
 727 EXPORT_SYMBOL_GPL(tpm_show_owned);
 728
 729 ssize_t tpm_show_temp_deactivated(struct device * dev,
 730                                 struct device_attribute * attr, char *buf)
 731 {
 732         cap_t cap;
 733         ssize_t rc;
 734
 735         rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
 736                          "attempting to determine the temporary state");
 737         if (rc)
 738                 return 0;
 739
 740         rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
 741         return rc;
 742 }
 743 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
 744
 745 /*
 746  * tpm_chip_find_get - return tpm_chip for given chip number
 747  */
 748 static struct tpm_chip *tpm_chip_find_get(int chip_num)
 749 {
 750         struct tpm_chip *pos, *chip = NULL;
 751
 752         rcu_read_lock();
 753         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
 754                 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
 755                         continue;
 756
 757                 if (try_module_get(pos->dev->driver->owner)) {
 758                         chip = pos;
 759                         break;
 760                 }
 761         }
 762         rcu_read_unlock();
 763         return chip;
 764 }
 765
 766 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
 767 #define READ_PCR_RESULT_SIZE 30
 768 static struct tpm_input_header pcrread_header = {
 769         .tag = TPM_TAG_RQU_COMMAND,
 770         .length = cpu_to_be32(14),
 771         .ordinal = TPM_ORDINAL_PCRREAD
 772 };
 773
 774 static int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 775 {
 776         int rc;
 777         struct tpm_cmd_t cmd;
 778
 779         cmd.header.in = pcrread_header;
 780         cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
 781         rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
 782                           "attempting to read a pcr value");
 783
 784         if (rc == 0)
 785                 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
 786                        TPM_DIGEST_SIZE);
 787         return rc;
 788 }
 789
 790 /**
 791  * tpm_pcr_read - read a pcr value
 792  * @chip_num:   tpm idx # or ANY
 793  * @pcr_idx:    pcr idx to retrieve
 794  * @res_buf:    TPM_PCR value
 795  *              size of res_buf is 20 bytes (or NULL if you don't care)
 796  *
 797  * The TPM driver should be built-in, but for whatever reason it
 798  * isn't, protect against the chip disappearing, by incrementing
 799  * the module usage count.
 800  */
 801 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
 802 {
 803         struct tpm_chip *chip;
 804         int rc;
 805
 806         chip = tpm_chip_find_get(chip_num);
 807         if (chip == NULL)
 808                 return -ENODEV;
 809         rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
 810         tpm_chip_put(chip);
 811         return rc;
 812 }
 813 EXPORT_SYMBOL_GPL(tpm_pcr_read);
 814
 815 /**
 816  * tpm_pcr_extend - extend pcr value with hash
 817  * @chip_num:   tpm idx # or AN&
 818  * @pcr_idx:    pcr idx to extend
 819  * @hash:       hash value used to extend pcr value
 820  *
 821  * The TPM driver should be built-in, but for whatever reason it
 822  * isn't, protect against the chip disappearing, by incrementing
 823  * the module usage count.
 824  */
 825 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
 826 #define EXTEND_PCR_RESULT_SIZE 34
 827 static struct tpm_input_header pcrextend_header = {
 828         .tag = TPM_TAG_RQU_COMMAND,
 829         .length = cpu_to_be32(34),
 830         .ordinal = TPM_ORD_PCR_EXTEND
 831 };
 832
 833 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
 834 {
 835         struct tpm_cmd_t cmd;
 836         int rc;
 837         struct tpm_chip *chip;
 838
 839         chip = tpm_chip_find_get(chip_num);
 840         if (chip == NULL)
 841                 return -ENODEV;
 842
 843         cmd.header.in = pcrextend_header;
 844         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
 845         memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
 846         rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
 847                           "attempting extend a PCR value");
 848
 849         tpm_chip_put(chip);
 850         return rc;
 851 }
 852 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
 853
 854 /**
 855  * tpm_do_selftest - have the TPM continue its selftest and wait until it
 856  *                   can receive further commands
 857  * @chip: TPM chip to use
 858  *
 859  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
 860  * a TPM error code.
 861  */
 862 int tpm_do_selftest(struct tpm_chip *chip)
 863 {
 864         int rc;
 865         u8 digest[TPM_DIGEST_SIZE];
 866         unsigned int loops;
 867         unsigned int delay_msec = 1000;
 868         unsigned long duration;
 869
 870         duration = tpm_calc_ordinal_duration(chip,
 871                                              TPM_ORD_CONTINUE_SELFTEST);
 872
 873         loops = jiffies_to_msecs(duration) / delay_msec;
 874
 875         rc = tpm_continue_selftest(chip);
 876         /* This may fail if there was no TPM driver during a suspend/resume
 877          * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
 878          */
 879         if (rc)
 880                 return rc;
 881
 882         do {
 883                 rc = __tpm_pcr_read(chip, 0, digest);
 884                 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
 885                         dev_info(chip->dev,
 886                                  "TPM is disabled/deactivated (0x%X)\n", rc);
 887                         /* TPM is disabled and/or deactivated; driver can
 888                          * proceed and TPM does handle commands for
 889                          * suspend/resume correctly
 890                          */
 891                         return 0;
 892                 }
 893                 if (rc != TPM_WARN_DOING_SELFTEST)
 894                         return rc;
 895                 msleep(delay_msec);
 896         } while (--loops > 0);
 897
 898         return rc;
 899 }
 900 EXPORT_SYMBOL_GPL(tpm_do_selftest);
 901
 902 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
 903 {
 904         struct tpm_chip *chip;
 905         int rc;
 906
 907         chip = tpm_chip_find_get(chip_num);
 908         if (chip == NULL)
 909                 return -ENODEV;
 910
 911         rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
 912
 913         tpm_chip_put(chip);
 914         return rc;
 915 }
 916 EXPORT_SYMBOL_GPL(tpm_send);
 917
 918 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
 919                       char *buf)
 920 {
 921         cap_t cap;
 922         u8 digest[TPM_DIGEST_SIZE];
 923         ssize_t rc;
 924         int i, j, num_pcrs;
 925         char *str = buf;
 926         struct tpm_chip *chip = dev_get_drvdata(dev);
 927
 928         rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
 929                         "attempting to determine the number of PCRS");
 930         if (rc)
 931                 return 0;
 932
 933         num_pcrs = be32_to_cpu(cap.num_pcrs);
 934         for (i = 0; i < num_pcrs; i++) {
 935                 rc = __tpm_pcr_read(chip, i, digest);
 936                 if (rc)
 937                         break;
 938                 str += sprintf(str, "PCR-%02d: ", i);
 939                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
 940                         str += sprintf(str, "%02X ", digest[j]);
 941                 str += sprintf(str, "\n");
 942         }
 943         return str - buf;
 944 }
 945 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 946
 947 #define  READ_PUBEK_RESULT_SIZE 314
 948 #define TPM_ORD_READPUBEK cpu_to_be32(124)
 949 struct tpm_input_header tpm_readpubek_header = {
 950         .tag = TPM_TAG_RQU_COMMAND,
 951         .length = cpu_to_be32(30),
 952         .ordinal = TPM_ORD_READPUBEK
 953 };
 954
 955 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
 956                        char *buf)
 957 {
 958         u8 *data;
 959         struct tpm_cmd_t tpm_cmd;
 960         ssize_t err;
 961         int i, rc;
 962         char *str = buf;
 963
 964         struct tpm_chip *chip = dev_get_drvdata(dev);
 965
 966         tpm_cmd.header.in = tpm_readpubek_header;
 967         err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
 968                         "attempting to read the PUBEK");
 969         if (err)
 970                 goto out;
 971
 972         /*
 973            ignore header 10 bytes
 974            algorithm 32 bits (1 == RSA )
 975            encscheme 16 bits
 976            sigscheme 16 bits
 977            parameters (RSA 12->bytes: keybit, #primes, expbit)
 978            keylenbytes 32 bits
 979            256 byte modulus
 980            ignore checksum 20 bytes
 981          */
 982         data = tpm_cmd.params.readpubek_out_buffer;
 983         str +=
 984             sprintf(str,
 985                     "Algorithm: %02X %02X %02X %02X\n"
 986                     "Encscheme: %02X %02X\n"
 987                     "Sigscheme: %02X %02X\n"
 988                     "Parameters: %02X %02X %02X %02X "
 989                     "%02X %02X %02X %02X "
 990                     "%02X %02X %02X %02X\n"
 991                     "Modulus length: %d\n"
 992                     "Modulus:\n",
 993                     data[0], data[1], data[2], data[3],
 994                     data[4], data[5],
 995                     data[6], data[7],
 996                     data[12], data[13], data[14], data[15],
 997                     data[16], data[17], data[18], data[19],
 998                     data[20], data[21], data[22], data[23],
 999                     be32_to_cpu(*((__be32 *) (data + 24))));
1000
1001         for (i = 0; i < 256; i++) {
1002                 str += sprintf(str, "%02X ", data[i + 28]);
1003                 if ((i + 1) % 16 == 0)
1004                         str += sprintf(str, "\n");
1005         }
1006 out:
1007         rc = str - buf;
1008         return rc;
1009 }
1010 EXPORT_SYMBOL_GPL(tpm_show_pubek);
1011
1012
1013 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
1014                       char *buf)
1015 {
1016         cap_t cap;
1017         ssize_t rc;
1018         char *str = buf;
1019
1020         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
1021                         "attempting to determine the manufacturer");
1022         if (rc)
1023                 return 0;
1024         str += sprintf(str, "Manufacturer: 0x%x\n",
1025                        be32_to_cpu(cap.manufacturer_id));
1026
1027         rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
1028                         "attempting to determine the 1.1 version");
1029         if (rc)
1030                 return 0;
1031         str += sprintf(str,
1032                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
1033                        cap.tpm_version.Major, cap.tpm_version.Minor,
1034                        cap.tpm_version.revMajor, cap.tpm_version.revMinor);
1035         return str - buf;
1036 }
1037 EXPORT_SYMBOL_GPL(tpm_show_caps);
1038
1039 ssize_t tpm_show_caps_1_2(struct device * dev,
1040                           struct device_attribute * attr, char *buf)
1041 {
1042         cap_t cap;
1043         ssize_t rc;
1044         char *str = buf;
1045
1046         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
1047                         "attempting to determine the manufacturer");
1048         if (rc)
1049                 return 0;
1050         str += sprintf(str, "Manufacturer: 0x%x\n",
1051                        be32_to_cpu(cap.manufacturer_id));
1052         rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
1053                          "attempting to determine the 1.2 version");
1054         if (rc)
1055                 return 0;
1056         str += sprintf(str,
1057                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
1058                        cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
1059                        cap.tpm_version_1_2.revMajor,
1060                        cap.tpm_version_1_2.revMinor);
1061         return str - buf;
1062 }
1063 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
1064
1065 ssize_t tpm_show_durations(struct device *dev, struct device_attribute *attr,
1066                           char *buf)
1067 {
1068         struct tpm_chip *chip = dev_get_drvdata(dev);
1069
1070         if (chip->vendor.duration[TPM_LONG] == 0)
1071                 return 0;
1072
1073         return sprintf(buf, "%d %d %d [%s]\n",
1074                        jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
1075                        jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
1076                        jiffies_to_usecs(chip->vendor.duration[TPM_LONG]),
1077                        chip->vendor.duration_adjusted
1078                        ? "adjusted" : "original");
1079 }
1080 EXPORT_SYMBOL_GPL(tpm_show_durations);
1081
1082 ssize_t tpm_show_timeouts(struct device *dev, struct device_attribute *attr,
1083                           char *buf)
1084 {
1085         struct tpm_chip *chip = dev_get_drvdata(dev);
1086
1087         return sprintf(buf, "%d %d %d %d [%s]\n",
1088                        jiffies_to_usecs(chip->vendor.timeout_a),
1089                        jiffies_to_usecs(chip->vendor.timeout_b),
1090                        jiffies_to_usecs(chip->vendor.timeout_c),
1091                        jiffies_to_usecs(chip->vendor.timeout_d),
1092                        chip->vendor.timeout_adjusted
1093                        ? "adjusted" : "original");
1094 }
1095 EXPORT_SYMBOL_GPL(tpm_show_timeouts);
1096
1097 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
1098                         const char *buf, size_t count)
1099 {
1100         struct tpm_chip *chip = dev_get_drvdata(dev);
1101         if (chip == NULL)
1102                 return 0;
1103
1104         chip->vendor.cancel(chip);
1105         return count;
1106 }
1107 EXPORT_SYMBOL_GPL(tpm_store_cancel);
1108
1109 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
1110                          wait_queue_head_t *queue)
1111 {
1112         unsigned long stop;
1113         long rc;
1114         u8 status;
1115
1116         /* check current status */
1117         status = chip->vendor.status(chip);
1118         if ((status & mask) == mask)
1119                 return 0;
1120
1121         stop = jiffies + timeout;
1122
1123         if (chip->vendor.irq) {
1124 again:
1125                 timeout = stop - jiffies;
1126                 if ((long)timeout <= 0)
1127                         return -ETIME;
1128                 rc = wait_event_interruptible_timeout(*queue,
1129                                                       ((chip->vendor.status(chip)
1130                                                       & mask) == mask),
1131                                                       timeout);
1132                 if (rc > 0)
1133                         return 0;
1134                 if (rc == -ERESTARTSYS && freezing(current)) {
1135                         clear_thread_flag(TIF_SIGPENDING);
1136                         goto again;
1137                 }
1138         } else {
1139                 do {
1140                         msleep(TPM_TIMEOUT);
1141                         status = chip->vendor.status(chip);
1142                         if ((status & mask) == mask)
1143                                 return 0;
1144                 } while (time_before(jiffies, stop));
1145         }
1146         return -ETIME;
1147 }
1148 EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
1149 /*
1150  * Device file system interface to the TPM
1151  *
1152  * It's assured that the chip will be opened just once,
1153  * by the check of is_open variable, which is protected
1154  * by driver_lock.
1155  */
1156 int tpm_open(struct inode *inode, struct file *file)
1157 {
1158         int minor = iminor(inode);
1159         struct tpm_chip *chip = NULL, *pos;
1160
1161         rcu_read_lock();
1162         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
1163                 if (pos->vendor.miscdev.minor == minor) {
1164                         chip = pos;
1165                         get_device(chip->dev);
1166                         break;
1167                 }
1168         }
1169         rcu_read_unlock();
1170
1171         if (!chip)
1172                 return -ENODEV;
1173
1174         if (test_and_set_bit(0, &chip->is_open)) {
1175                 dev_dbg(chip->dev, "Another process owns this TPM\n");
1176                 put_device(chip->dev);
1177                 return -EBUSY;
1178         }
1179
1180         chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
1181         if (chip->data_buffer == NULL) {
1182                 clear_bit(0, &chip->is_open);
1183                 put_device(chip->dev);
1184                 return -ENOMEM;
1185         }
1186
1187         atomic_set(&chip->data_pending, 0);
1188
1189         file->private_data = chip;
1190         return 0;
1191 }
1192 EXPORT_SYMBOL_GPL(tpm_open);
1193
1194 /*
1195  * Called on file close
1196  */
1197 int tpm_release(struct inode *inode, struct file *file)
1198 {
1199         struct tpm_chip *chip = file->private_data;
1200
1201         del_singleshot_timer_sync(&chip->user_read_timer);
1202         flush_work_sync(&chip->work);
1203         file->private_data = NULL;
1204         atomic_set(&chip->data_pending, 0);
1205         kfree(chip->data_buffer);
1206         clear_bit(0, &chip->is_open);
1207         put_device(chip->dev);
1208         return 0;
1209 }
1210 EXPORT_SYMBOL_GPL(tpm_release);
1211
1212 ssize_t tpm_write(struct file *file, const char __user *buf,
1213                   size_t size, loff_t *off)
1214 {
1215         struct tpm_chip *chip = file->private_data;
1216         size_t in_size = size, out_size;
1217
1218         /* cannot perform a write until the read has cleared
1219            either via tpm_read or a user_read_timer timeout */
1220         while (atomic_read(&chip->data_pending) != 0)
1221                 msleep(TPM_TIMEOUT);
1222
1223         resume_if_needed(chip);
1224
1225         mutex_lock(&chip->buffer_mutex);
1226
1227         if (in_size > TPM_BUFSIZE)
1228                 in_size = TPM_BUFSIZE;
1229
1230         if (copy_from_user
1231             (chip->data_buffer, (void __user *) buf, in_size)) {
1232                 mutex_unlock(&chip->buffer_mutex);
1233                 return -EFAULT;
1234         }
1235
1236         /* atomic tpm command send and result receive */
1237         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1238
1239         atomic_set(&chip->data_pending, out_size);
1240         mutex_unlock(&chip->buffer_mutex);
1241
1242         /* Set a timeout by which the reader must come claim the result */
1243         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1244
1245         return in_size;
1246 }
1247 EXPORT_SYMBOL_GPL(tpm_write);
1248
1249 ssize_t tpm_read(struct file *file, char __user *buf,
1250                  size_t size, loff_t *off)
1251 {
1252         struct tpm_chip *chip = file->private_data;
1253         ssize_t ret_size;
1254         int rc;
1255
1256         del_singleshot_timer_sync(&chip->user_read_timer);
1257         flush_work_sync(&chip->work);
1258         ret_size = atomic_read(&chip->data_pending);
1259         /* TODO(wad): atomic_set should come AFTER the buffer is copied. */
1260         atomic_set(&chip->data_pending, 0);
1261         if (ret_size > 0) {     /* relay data */
1262                 ssize_t orig_ret_size = ret_size;
1263                 if (size < ret_size)
1264                         ret_size = size;
1265
1266                 mutex_lock(&chip->buffer_mutex);
1267                 rc = copy_to_user(buf, chip->data_buffer, ret_size);
1268                 memset(chip->data_buffer, 0, orig_ret_size);
1269                 if (rc)
1270                         ret_size = -EFAULT;
1271
1272                 mutex_unlock(&chip->buffer_mutex);
1273         }
1274
1275         return ret_size;
1276 }
1277 EXPORT_SYMBOL_GPL(tpm_read);
1278
1279 void tpm_remove_hardware(struct device *dev)
1280 {
1281         struct tpm_chip *chip = dev_get_drvdata(dev);
1282
1283         if (chip == NULL) {
1284                 dev_err(dev, "No device data found\n");
1285                 return;
1286         }
1287
1288         spin_lock(&driver_lock);
1289         list_del_rcu(&chip->list);
1290         spin_unlock(&driver_lock);
1291         synchronize_rcu();
1292
1293         misc_deregister(&chip->vendor.miscdev);
1294         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1295         tpm_bios_log_teardown(chip->bios_dir);
1296
1297         /* write it this way to be explicit (chip->dev == dev) */
1298         put_device(chip->dev);
1299 }
1300 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1301
1302 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1303 #define SAVESTATE_RESULT_SIZE 10
1304
1305 static struct tpm_input_header savestate_header = {
1306         .tag = TPM_TAG_RQU_COMMAND,
1307         .length = cpu_to_be32(10),
1308         .ordinal = TPM_ORD_SAVESTATE
1309 };
1310
1311 /*
1312  * We are about to suspend. Save the TPM state
1313  * so that it can be restored.
1314  */
1315 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1316 {
1317         struct tpm_chip *chip = dev_get_drvdata(dev);
1318         struct tpm_cmd_t cmd;
1319         int rc;
1320
1321         u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1322
1323         if (chip == NULL)
1324                 return -ENODEV;
1325
1326         /* for buggy tpm, flush pcrs with extend to selected dummy */
1327         if (tpm_suspend_pcr) {
1328                 cmd.header.in = pcrextend_header;
1329                 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1330                 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1331                        TPM_DIGEST_SIZE);
1332                 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1333                                   "extending dummy pcr before suspend");
1334         }
1335
1336         /* now do the actual savestate */
1337         cmd.header.in = savestate_header;
1338         rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE,
1339                           "sending savestate before suspend");
1340         return rc;
1341 }
1342 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1343
1344 /*
1345  * Resume from a power safe. The BIOS already restored
1346  * the TPM state.
1347  */
1348 int tpm_pm_resume(struct device *dev)
1349 {
1350         struct tpm_chip *chip = dev_get_drvdata(dev);
1351
1352         if (chip == NULL)
1353                 return -ENODEV;
1354
1355         needs_resume(chip);
1356         return 0;
1357 }
1358 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1359
1360 /* In case vendor provided release function, call it too.*/
1361
1362 void tpm_dev_vendor_release(struct tpm_chip *chip)
1363 {
1364         if (chip->vendor.release)
1365                 chip->vendor.release(chip->dev);
1366
1367         clear_bit(chip->dev_num, dev_mask);
1368         kfree(chip->vendor.miscdev.name);
1369 }
1370 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1371
1372
1373 /*
1374  * Once all references to platform device are down to 0,
1375  * release all allocated structures.
1376  */
1377 void tpm_dev_release(struct device *dev)
1378 {
1379         struct tpm_chip *chip = dev_get_drvdata(dev);
1380
1381         tpm_dev_vendor_release(chip);
1382
1383         chip->release(dev);
1384         kfree(chip);
1385 }
1386 EXPORT_SYMBOL_GPL(tpm_dev_release);
1387
1388 /*
1389  * Called from tpm_<specific>.c probe function only for devices
1390  * the driver has determined it should claim.  Prior to calling
1391  * this function the specific probe function has called pci_enable_device
1392  * upon errant exit from this function specific probe function should call
1393  * pci_disable_device
1394  */
1395 struct tpm_chip *tpm_register_hardware(struct device *dev,
1396                                         const struct tpm_vendor_specific *entry)
1397 {
1398 #define DEVNAME_SIZE 7
1399
1400         char *devname;
1401         struct tpm_chip *chip;
1402
1403         /* Driver specific per-device data */
1404         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1405         devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1406
1407         if (chip == NULL || devname == NULL)
1408                 goto out_free;
1409
1410         mutex_init(&chip->buffer_mutex);
1411         mutex_init(&chip->tpm_mutex);
1412         mutex_init(&chip->resume_mutex);
1413         INIT_LIST_HEAD(&chip->list);
1414
1415         INIT_WORK(&chip->work, timeout_work);
1416
1417         setup_timer(&chip->user_read_timer, user_reader_timeout,
1418                         (unsigned long)chip);
1419
1420         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1421
1422         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1423
1424         if (chip->dev_num >= TPM_NUM_DEVICES) {
1425                 dev_err(dev, "No available tpm device numbers\n");
1426                 goto out_free;
1427         } else if (chip->dev_num == 0)
1428                 chip->vendor.miscdev.minor = TPM_MINOR;
1429         else
1430                 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1431
1432         set_bit(chip->dev_num, dev_mask);
1433
1434         scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1435         chip->vendor.miscdev.name = devname;
1436
1437         chip->vendor.miscdev.parent = dev;
1438         chip->dev = get_device(dev);
1439         chip->release = dev->release;
1440         dev->release = tpm_dev_release;
1441         dev_set_drvdata(dev, chip);
1442
1443         if (misc_register(&chip->vendor.miscdev)) {
1444                 dev_err(chip->dev,
1445                         "unable to misc_register %s, minor %d\n",
1446                         chip->vendor.miscdev.name,
1447                         chip->vendor.miscdev.minor);
1448                 put_device(chip->dev);
1449                 return NULL;
1450         }
1451
1452         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1453                 misc_deregister(&chip->vendor.miscdev);
1454                 put_device(chip->dev);
1455
1456                 return NULL;
1457         }
1458
1459         chip->bios_dir = tpm_bios_log_setup(devname);
1460
1461         /* Make chip available */
1462         spin_lock(&driver_lock);
1463         list_add_rcu(&chip->list, &tpm_chip_list);
1464         spin_unlock(&driver_lock);
1465
1466         return chip;
1467
1468 out_free:
1469         kfree(chip);
1470         kfree(devname);
1471         return NULL;
1472 }
1473 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1474
1475 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1476 MODULE_DESCRIPTION("TPM Driver");
1477 MODULE_VERSION("2.0");
1478 MODULE_LICENSE("GPL");