drivers/char/tpm/tpm-interface.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 TSC_MAX_ORDINAL 12
  44 #define TPM_PROTECTED_COMMAND 0x00
  45 #define TPM_CONNECTION_COMMAND 0x40
  46
  47 /*
  48  * Bug workaround - some TPM's don't flush the most
  49  * recently changed pcr on suspend, so force the flush
  50  * with an extend to the selected _unused_ non-volatile pcr.
  51  */
  52 static int tpm_suspend_pcr;
  53 module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644);
  54 MODULE_PARM_DESC(suspend_pcr,
  55                  "PCR to use for dummy writes to faciltate flush on suspend.");
  56
  57 static LIST_HEAD(tpm_chip_list);
  58 static DEFINE_SPINLOCK(driver_lock);
  59 static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
  60
  61 /*
  62  * Array with one entry per ordinal defining the maximum amount
  63  * of time the chip could take to return the result.  The ordinal
  64  * designation of short, medium or long is defined in a table in
  65  * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
  66  * values of the SHORT, MEDIUM, and LONG durations are retrieved
  67  * from the chip during initialization with a call to tpm_get_timeouts.
  68  */
  69 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
  70         TPM_UNDEFINED,          /* 0 */
  71         TPM_UNDEFINED,
  72         TPM_UNDEFINED,
  73         TPM_UNDEFINED,
  74         TPM_UNDEFINED,
  75         TPM_UNDEFINED,          /* 5 */
  76         TPM_UNDEFINED,
  77         TPM_UNDEFINED,
  78         TPM_UNDEFINED,
  79         TPM_UNDEFINED,
  80         TPM_SHORT,              /* 10 */
  81         TPM_SHORT,
  82         TPM_MEDIUM,
  83         TPM_LONG,
  84         TPM_LONG,
  85         TPM_MEDIUM,             /* 15 */
  86         TPM_SHORT,
  87         TPM_SHORT,
  88         TPM_MEDIUM,
  89         TPM_LONG,
  90         TPM_SHORT,              /* 20 */
  91         TPM_SHORT,
  92         TPM_MEDIUM,
  93         TPM_MEDIUM,
  94         TPM_MEDIUM,
  95         TPM_SHORT,              /* 25 */
  96         TPM_SHORT,
  97         TPM_MEDIUM,
  98         TPM_SHORT,
  99         TPM_SHORT,
 100         TPM_MEDIUM,             /* 30 */
 101         TPM_LONG,
 102         TPM_MEDIUM,
 103         TPM_SHORT,
 104         TPM_SHORT,
 105         TPM_SHORT,              /* 35 */
 106         TPM_MEDIUM,
 107         TPM_MEDIUM,
 108         TPM_UNDEFINED,
 109         TPM_UNDEFINED,
 110         TPM_MEDIUM,             /* 40 */
 111         TPM_LONG,
 112         TPM_MEDIUM,
 113         TPM_SHORT,
 114         TPM_SHORT,
 115         TPM_SHORT,              /* 45 */
 116         TPM_SHORT,
 117         TPM_SHORT,
 118         TPM_SHORT,
 119         TPM_LONG,
 120         TPM_MEDIUM,             /* 50 */
 121         TPM_MEDIUM,
 122         TPM_UNDEFINED,
 123         TPM_UNDEFINED,
 124         TPM_UNDEFINED,
 125         TPM_UNDEFINED,          /* 55 */
 126         TPM_UNDEFINED,
 127         TPM_UNDEFINED,
 128         TPM_UNDEFINED,
 129         TPM_UNDEFINED,
 130         TPM_MEDIUM,             /* 60 */
 131         TPM_MEDIUM,
 132         TPM_MEDIUM,
 133         TPM_SHORT,
 134         TPM_SHORT,
 135         TPM_MEDIUM,             /* 65 */
 136         TPM_UNDEFINED,
 137         TPM_UNDEFINED,
 138         TPM_UNDEFINED,
 139         TPM_UNDEFINED,
 140         TPM_SHORT,              /* 70 */
 141         TPM_SHORT,
 142         TPM_UNDEFINED,
 143         TPM_UNDEFINED,
 144         TPM_UNDEFINED,
 145         TPM_UNDEFINED,          /* 75 */
 146         TPM_UNDEFINED,
 147         TPM_UNDEFINED,
 148         TPM_UNDEFINED,
 149         TPM_UNDEFINED,
 150         TPM_LONG,               /* 80 */
 151         TPM_UNDEFINED,
 152         TPM_MEDIUM,
 153         TPM_LONG,
 154         TPM_SHORT,
 155         TPM_UNDEFINED,          /* 85 */
 156         TPM_UNDEFINED,
 157         TPM_UNDEFINED,
 158         TPM_UNDEFINED,
 159         TPM_UNDEFINED,
 160         TPM_SHORT,              /* 90 */
 161         TPM_SHORT,
 162         TPM_SHORT,
 163         TPM_SHORT,
 164         TPM_SHORT,
 165         TPM_UNDEFINED,          /* 95 */
 166         TPM_UNDEFINED,
 167         TPM_UNDEFINED,
 168         TPM_UNDEFINED,
 169         TPM_UNDEFINED,
 170         TPM_MEDIUM,             /* 100 */
 171         TPM_SHORT,
 172         TPM_SHORT,
 173         TPM_UNDEFINED,
 174         TPM_UNDEFINED,
 175         TPM_UNDEFINED,          /* 105 */
 176         TPM_UNDEFINED,
 177         TPM_UNDEFINED,
 178         TPM_UNDEFINED,
 179         TPM_UNDEFINED,
 180         TPM_SHORT,              /* 110 */
 181         TPM_SHORT,
 182         TPM_SHORT,
 183         TPM_SHORT,
 184         TPM_SHORT,
 185         TPM_SHORT,              /* 115 */
 186         TPM_SHORT,
 187         TPM_SHORT,
 188         TPM_UNDEFINED,
 189         TPM_UNDEFINED,
 190         TPM_LONG,               /* 120 */
 191         TPM_LONG,
 192         TPM_MEDIUM,
 193         TPM_UNDEFINED,
 194         TPM_SHORT,
 195         TPM_SHORT,              /* 125 */
 196         TPM_SHORT,
 197         TPM_LONG,
 198         TPM_SHORT,
 199         TPM_SHORT,
 200         TPM_SHORT,              /* 130 */
 201         TPM_MEDIUM,
 202         TPM_UNDEFINED,
 203         TPM_SHORT,
 204         TPM_MEDIUM,
 205         TPM_UNDEFINED,          /* 135 */
 206         TPM_UNDEFINED,
 207         TPM_UNDEFINED,
 208         TPM_UNDEFINED,
 209         TPM_UNDEFINED,
 210         TPM_SHORT,              /* 140 */
 211         TPM_SHORT,
 212         TPM_UNDEFINED,
 213         TPM_UNDEFINED,
 214         TPM_UNDEFINED,
 215         TPM_UNDEFINED,          /* 145 */
 216         TPM_UNDEFINED,
 217         TPM_UNDEFINED,
 218         TPM_UNDEFINED,
 219         TPM_UNDEFINED,
 220         TPM_SHORT,              /* 150 */
 221         TPM_MEDIUM,
 222         TPM_MEDIUM,
 223         TPM_SHORT,
 224         TPM_SHORT,
 225         TPM_UNDEFINED,          /* 155 */
 226         TPM_UNDEFINED,
 227         TPM_UNDEFINED,
 228         TPM_UNDEFINED,
 229         TPM_UNDEFINED,
 230         TPM_SHORT,              /* 160 */
 231         TPM_SHORT,
 232         TPM_SHORT,
 233         TPM_SHORT,
 234         TPM_UNDEFINED,
 235         TPM_UNDEFINED,          /* 165 */
 236         TPM_UNDEFINED,
 237         TPM_UNDEFINED,
 238         TPM_UNDEFINED,
 239         TPM_UNDEFINED,
 240         TPM_LONG,               /* 170 */
 241         TPM_UNDEFINED,
 242         TPM_UNDEFINED,
 243         TPM_UNDEFINED,
 244         TPM_UNDEFINED,
 245         TPM_UNDEFINED,          /* 175 */
 246         TPM_UNDEFINED,
 247         TPM_UNDEFINED,
 248         TPM_UNDEFINED,
 249         TPM_UNDEFINED,
 250         TPM_MEDIUM,             /* 180 */
 251         TPM_SHORT,
 252         TPM_MEDIUM,
 253         TPM_MEDIUM,
 254         TPM_MEDIUM,
 255         TPM_MEDIUM,             /* 185 */
 256         TPM_SHORT,
 257         TPM_UNDEFINED,
 258         TPM_UNDEFINED,
 259         TPM_UNDEFINED,
 260         TPM_UNDEFINED,          /* 190 */
 261         TPM_UNDEFINED,
 262         TPM_UNDEFINED,
 263         TPM_UNDEFINED,
 264         TPM_UNDEFINED,
 265         TPM_UNDEFINED,          /* 195 */
 266         TPM_UNDEFINED,
 267         TPM_UNDEFINED,
 268         TPM_UNDEFINED,
 269         TPM_UNDEFINED,
 270         TPM_SHORT,              /* 200 */
 271         TPM_UNDEFINED,
 272         TPM_UNDEFINED,
 273         TPM_UNDEFINED,
 274         TPM_SHORT,
 275         TPM_SHORT,              /* 205 */
 276         TPM_SHORT,
 277         TPM_SHORT,
 278         TPM_SHORT,
 279         TPM_SHORT,
 280         TPM_MEDIUM,             /* 210 */
 281         TPM_UNDEFINED,
 282         TPM_MEDIUM,
 283         TPM_MEDIUM,
 284         TPM_MEDIUM,
 285         TPM_UNDEFINED,          /* 215 */
 286         TPM_MEDIUM,
 287         TPM_UNDEFINED,
 288         TPM_UNDEFINED,
 289         TPM_SHORT,
 290         TPM_SHORT,              /* 220 */
 291         TPM_SHORT,
 292         TPM_SHORT,
 293         TPM_SHORT,
 294         TPM_SHORT,
 295         TPM_UNDEFINED,          /* 225 */
 296         TPM_UNDEFINED,
 297         TPM_UNDEFINED,
 298         TPM_UNDEFINED,
 299         TPM_UNDEFINED,
 300         TPM_SHORT,              /* 230 */
 301         TPM_LONG,
 302         TPM_MEDIUM,
 303         TPM_UNDEFINED,
 304         TPM_UNDEFINED,
 305         TPM_UNDEFINED,          /* 235 */
 306         TPM_UNDEFINED,
 307         TPM_UNDEFINED,
 308         TPM_UNDEFINED,
 309         TPM_UNDEFINED,
 310         TPM_SHORT,              /* 240 */
 311         TPM_UNDEFINED,
 312         TPM_MEDIUM,
 313 };
 314
 315 static void user_reader_timeout(unsigned long ptr)
 316 {
 317         struct tpm_chip *chip = (struct tpm_chip *) ptr;
 318
 319         schedule_work(&chip->work);
 320 }
 321
 322 static void timeout_work(struct work_struct *work)
 323 {
 324         struct tpm_chip *chip = container_of(work, struct tpm_chip, work);
 325
 326         mutex_lock(&chip->buffer_mutex);
 327         atomic_set(&chip->data_pending, 0);
 328         memset(chip->data_buffer, 0, TPM_BUFSIZE);
 329         mutex_unlock(&chip->buffer_mutex);
 330 }
 331
 332 /*
 333  * Returns max number of jiffies to wait
 334  */
 335 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
 336                                            u32 ordinal)
 337 {
 338         int duration_idx = TPM_UNDEFINED;
 339         int duration = 0;
 340         u8 category = (ordinal >> 24) & 0xFF;
 341
 342         if ((category == TPM_PROTECTED_COMMAND && ordinal < TPM_MAX_ORDINAL) ||
 343             (category == TPM_CONNECTION_COMMAND && ordinal < TSC_MAX_ORDINAL))
 344                 duration_idx = tpm_ordinal_duration[ordinal];
 345
 346         if (duration_idx != TPM_UNDEFINED)
 347                 duration = chip->vendor.duration[duration_idx];
 348         if (duration <= 0)
 349                 return 2 * 60 * HZ;
 350         else
 351                 return duration;
 352 }
 353 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 354
 355 /*
 356  * Internal kernel interface to transmit TPM commands
 357  */
 358 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
 359                             size_t bufsiz)
 360 {
 361         ssize_t rc;
 362         u32 count, ordinal;
 363         unsigned long stop;
 364
 365         if (bufsiz > TPM_BUFSIZE)
 366                 bufsiz = TPM_BUFSIZE;
 367
 368         count = be32_to_cpu(*((__be32 *) (buf + 2)));
 369         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
 370         if (count == 0)
 371                 return -ENODATA;
 372         if (count > bufsiz) {
 373                 dev_err(chip->dev,
 374                         "invalid count value %x %zx\n", count, bufsiz);
 375                 return -E2BIG;
 376         }
 377
 378         mutex_lock(&chip->tpm_mutex);
 379
 380         rc = chip->vendor.send(chip, (u8 *) buf, count);
 381         if (rc < 0) {
 382                 dev_err(chip->dev,
 383                         "tpm_transmit: tpm_send: error %zd\n", rc);
 384                 goto out;
 385         }
 386
 387         if (chip->vendor.irq)
 388                 goto out_recv;
 389
 390         stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
 391         do {
 392                 u8 status = chip->vendor.status(chip);
 393                 if ((status & chip->vendor.req_complete_mask) ==
 394                     chip->vendor.req_complete_val)
 395                         goto out_recv;
 396
 397                 if (chip->vendor.req_canceled(chip, status)) {
 398                         dev_err(chip->dev, "Operation Canceled\n");
 399                         rc = -ECANCELED;
 400                         goto out;
 401                 }
 402
 403                 msleep(TPM_TIMEOUT);    /* CHECK */
 404                 rmb();
 405         } while (time_before(jiffies, stop));
 406
 407         chip->vendor.cancel(chip);
 408         dev_err(chip->dev, "Operation Timed out\n");
 409         rc = -ETIME;
 410         goto out;
 411
 412 out_recv:
 413         rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
 414         if (rc < 0)
 415                 dev_err(chip->dev,
 416                         "tpm_transmit: tpm_recv: error %zd\n", rc);
 417 out:
 418         mutex_unlock(&chip->tpm_mutex);
 419         return rc;
 420 }
 421
 422 #define TPM_DIGEST_SIZE 20
 423 #define TPM_RET_CODE_IDX 6
 424
 425 enum tpm_capabilities {
 426         TPM_CAP_FLAG = cpu_to_be32(4),
 427         TPM_CAP_PROP = cpu_to_be32(5),
 428         CAP_VERSION_1_1 = cpu_to_be32(0x06),
 429         CAP_VERSION_1_2 = cpu_to_be32(0x1A)
 430 };
 431
 432 enum tpm_sub_capabilities {
 433         TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
 434         TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
 435         TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
 436         TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
 437         TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
 438         TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
 439         TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
 440
 441 };
 442
 443 static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
 444                             int len, const char *desc)
 445 {
 446         int err;
 447
 448         len = tpm_transmit(chip, (u8 *) cmd, len);
 449         if (len <  0)
 450                 return len;
 451         else if (len < TPM_HEADER_SIZE)
 452                 return -EFAULT;
 453
 454         err = be32_to_cpu(cmd->header.out.return_code);
 455         if (err != 0 && desc)
 456                 dev_err(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
 457
 458         return err;
 459 }
 460
 461 #define TPM_INTERNAL_RESULT_SIZE 200
 462 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
 463 #define TPM_ORD_GET_CAP cpu_to_be32(101)
 464 #define TPM_ORD_GET_RANDOM cpu_to_be32(70)
 465
 466 static const struct tpm_input_header tpm_getcap_header = {
 467         .tag = TPM_TAG_RQU_COMMAND,
 468         .length = cpu_to_be32(22),
 469         .ordinal = TPM_ORD_GET_CAP
 470 };
 471
 472 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
 473                    const char *desc)
 474 {
 475         struct tpm_cmd_t tpm_cmd;
 476         int rc;
 477         struct tpm_chip *chip = dev_get_drvdata(dev);
 478
 479         tpm_cmd.header.in = tpm_getcap_header;
 480         if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
 481                 tpm_cmd.params.getcap_in.cap = subcap_id;
 482                 /*subcap field not necessary */
 483                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
 484                 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
 485         } else {
 486                 if (subcap_id == TPM_CAP_FLAG_PERM ||
 487                     subcap_id == TPM_CAP_FLAG_VOL)
 488                         tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
 489                 else
 490                         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 491                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 492                 tpm_cmd.params.getcap_in.subcap = subcap_id;
 493         }
 494         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
 495         if (!rc)
 496                 *cap = tpm_cmd.params.getcap_out.cap;
 497         return rc;
 498 }
 499
 500 void tpm_gen_interrupt(struct tpm_chip *chip)
 501 {
 502         struct  tpm_cmd_t tpm_cmd;
 503         ssize_t rc;
 504
 505         tpm_cmd.header.in = tpm_getcap_header;
 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 = TPM_CAP_PROP_TIS_TIMEOUT;
 509
 510         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 511                         "attempting to determine the timeouts");
 512 }
 513 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
 514
 515 #define TPM_ORD_STARTUP cpu_to_be32(153)
 516 #define TPM_ST_CLEAR cpu_to_be16(1)
 517 #define TPM_ST_STATE cpu_to_be16(2)
 518 #define TPM_ST_DEACTIVATED cpu_to_be16(3)
 519 static const struct tpm_input_header tpm_startup_header = {
 520         .tag = TPM_TAG_RQU_COMMAND,
 521         .length = cpu_to_be32(12),
 522         .ordinal = TPM_ORD_STARTUP
 523 };
 524
 525 static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
 526 {
 527         struct tpm_cmd_t start_cmd;
 528         start_cmd.header.in = tpm_startup_header;
 529         start_cmd.params.startup_in.startup_type = startup_type;
 530         return transmit_cmd(chip, &start_cmd, TPM_INTERNAL_RESULT_SIZE,
 531                             "attempting to start the TPM");
 532 }
 533
 534 int tpm_get_timeouts(struct tpm_chip *chip)
 535 {
 536         struct tpm_cmd_t tpm_cmd;
 537         struct timeout_t *timeout_cap;
 538         struct duration_t *duration_cap;
 539         ssize_t rc;
 540         u32 timeout;
 541         unsigned int scale = 1;
 542
 543         tpm_cmd.header.in = tpm_getcap_header;
 544         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 545         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 546         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 547         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, NULL);
 548
 549         if (rc == TPM_ERR_INVALID_POSTINIT) {
 550                 /* The TPM is not started, we are the first to talk to it.
 551                    Execute a startup command. */
 552                 dev_info(chip->dev, "Issuing TPM_STARTUP");
 553                 if (tpm_startup(chip, TPM_ST_CLEAR))
 554                         return rc;
 555
 556                 tpm_cmd.header.in = tpm_getcap_header;
 557                 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 558                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 559                 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 560                 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 561                                   NULL);
 562         }
 563         if (rc) {
 564                 dev_err(chip->dev,
 565                         "A TPM error (%zd) occurred attempting to determine the timeouts\n",
 566                         rc);
 567                 goto duration;
 568         }
 569
 570         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 571             be32_to_cpu(tpm_cmd.header.out.length)
 572             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
 573                 return -EINVAL;
 574
 575         timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
 576         /* Don't overwrite default if value is 0 */
 577         timeout = be32_to_cpu(timeout_cap->a);
 578         if (timeout && timeout < 1000) {
 579                 /* timeouts in msec rather usec */
 580                 scale = 1000;
 581                 chip->vendor.timeout_adjusted = true;
 582         }
 583         if (timeout)
 584                 chip->vendor.timeout_a = usecs_to_jiffies(timeout * scale);
 585         timeout = be32_to_cpu(timeout_cap->b);
 586         if (timeout)
 587                 chip->vendor.timeout_b = usecs_to_jiffies(timeout * scale);
 588         timeout = be32_to_cpu(timeout_cap->c);
 589         if (timeout)
 590                 chip->vendor.timeout_c = usecs_to_jiffies(timeout * scale);
 591         timeout = be32_to_cpu(timeout_cap->d);
 592         if (timeout)
 593                 chip->vendor.timeout_d = usecs_to_jiffies(timeout * scale);
 594
 595 duration:
 596         tpm_cmd.header.in = tpm_getcap_header;
 597         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 598         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 599         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
 600
 601         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 602                         "attempting to determine the durations");
 603         if (rc)
 604                 return rc;
 605
 606         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 607             be32_to_cpu(tpm_cmd.header.out.length)
 608             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
 609                 return -EINVAL;
 610
 611         duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
 612         chip->vendor.duration[TPM_SHORT] =
 613             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
 614         chip->vendor.duration[TPM_MEDIUM] =
 615             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
 616         chip->vendor.duration[TPM_LONG] =
 617             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
 618
 619         /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
 620          * value wrong and apparently reports msecs rather than usecs. So we
 621          * fix up the resulting too-small TPM_SHORT value to make things work.
 622          * We also scale the TPM_MEDIUM and -_LONG values by 1000.
 623          */
 624         if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
 625                 chip->vendor.duration[TPM_SHORT] = HZ;
 626                 chip->vendor.duration[TPM_MEDIUM] *= 1000;
 627                 chip->vendor.duration[TPM_LONG] *= 1000;
 628                 chip->vendor.duration_adjusted = true;
 629                 dev_info(chip->dev, "Adjusting TPM timeout parameters.");
 630         }
 631         return 0;
 632 }
 633 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
 634
 635 #define TPM_ORD_CONTINUE_SELFTEST 83
 636 #define CONTINUE_SELFTEST_RESULT_SIZE 10
 637
 638 static struct tpm_input_header continue_selftest_header = {
 639         .tag = TPM_TAG_RQU_COMMAND,
 640         .length = cpu_to_be32(10),
 641         .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
 642 };
 643
 644 /**
 645  * tpm_continue_selftest -- run TPM's selftest
 646  * @chip: TPM chip to use
 647  *
 648  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
 649  * a TPM error code.
 650  */
 651 static int tpm_continue_selftest(struct tpm_chip *chip)
 652 {
 653         int rc;
 654         struct tpm_cmd_t cmd;
 655
 656         cmd.header.in = continue_selftest_header;
 657         rc = transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
 658                           "continue selftest");
 659         return rc;
 660 }
 661
 662 ssize_t tpm_show_enabled(struct device *dev, struct device_attribute *attr,
 663                         char *buf)
 664 {
 665         cap_t cap;
 666         ssize_t rc;
 667
 668         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 669                          "attempting to determine the permanent enabled state");
 670         if (rc)
 671                 return 0;
 672
 673         rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
 674         return rc;
 675 }
 676 EXPORT_SYMBOL_GPL(tpm_show_enabled);
 677
 678 ssize_t tpm_show_active(struct device *dev, struct device_attribute *attr,
 679                         char *buf)
 680 {
 681         cap_t cap;
 682         ssize_t rc;
 683
 684         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 685                          "attempting to determine the permanent active state");
 686         if (rc)
 687                 return 0;
 688
 689         rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
 690         return rc;
 691 }
 692 EXPORT_SYMBOL_GPL(tpm_show_active);
 693
 694 ssize_t tpm_show_owned(struct device *dev, struct device_attribute *attr,
 695                         char *buf)
 696 {
 697         cap_t cap;
 698         ssize_t rc;
 699
 700         rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
 701                          "attempting to determine the owner state");
 702         if (rc)
 703                 return 0;
 704
 705         rc = sprintf(buf, "%d\n", cap.owned);
 706         return rc;
 707 }
 708 EXPORT_SYMBOL_GPL(tpm_show_owned);
 709
 710 ssize_t tpm_show_temp_deactivated(struct device *dev,
 711                                 struct device_attribute *attr, char *buf)
 712 {
 713         cap_t cap;
 714         ssize_t rc;
 715
 716         rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
 717                          "attempting to determine the temporary state");
 718         if (rc)
 719                 return 0;
 720
 721         rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
 722         return rc;
 723 }
 724 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
 725
 726 /*
 727  * tpm_chip_find_get - return tpm_chip for given chip number
 728  */
 729 static struct tpm_chip *tpm_chip_find_get(int chip_num)
 730 {
 731         struct tpm_chip *pos, *chip = NULL;
 732
 733         rcu_read_lock();
 734         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
 735                 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
 736                         continue;
 737
 738                 if (try_module_get(pos->dev->driver->owner)) {
 739                         chip = pos;
 740                         break;
 741                 }
 742         }
 743         rcu_read_unlock();
 744         return chip;
 745 }
 746
 747 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
 748 #define READ_PCR_RESULT_SIZE 30
 749 static struct tpm_input_header pcrread_header = {
 750         .tag = TPM_TAG_RQU_COMMAND,
 751         .length = cpu_to_be32(14),
 752         .ordinal = TPM_ORDINAL_PCRREAD
 753 };
 754
 755 static int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 756 {
 757         int rc;
 758         struct tpm_cmd_t cmd;
 759
 760         cmd.header.in = pcrread_header;
 761         cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
 762         rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
 763                           "attempting to read a pcr value");
 764
 765         if (rc == 0)
 766                 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
 767                        TPM_DIGEST_SIZE);
 768         return rc;
 769 }
 770
 771 /**
 772  * tpm_pcr_read - read a pcr value
 773  * @chip_num:   tpm idx # or ANY
 774  * @pcr_idx:    pcr idx to retrieve
 775  * @res_buf:    TPM_PCR value
 776  *              size of res_buf is 20 bytes (or NULL if you don't care)
 777  *
 778  * The TPM driver should be built-in, but for whatever reason it
 779  * isn't, protect against the chip disappearing, by incrementing
 780  * the module usage count.
 781  */
 782 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
 783 {
 784         struct tpm_chip *chip;
 785         int rc;
 786
 787         chip = tpm_chip_find_get(chip_num);
 788         if (chip == NULL)
 789                 return -ENODEV;
 790         rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
 791         tpm_chip_put(chip);
 792         return rc;
 793 }
 794 EXPORT_SYMBOL_GPL(tpm_pcr_read);
 795
 796 /**
 797  * tpm_pcr_extend - extend pcr value with hash
 798  * @chip_num:   tpm idx # or AN&
 799  * @pcr_idx:    pcr idx to extend
 800  * @hash:       hash value used to extend pcr value
 801  *
 802  * The TPM driver should be built-in, but for whatever reason it
 803  * isn't, protect against the chip disappearing, by incrementing
 804  * the module usage count.
 805  */
 806 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
 807 #define EXTEND_PCR_RESULT_SIZE 34
 808 static struct tpm_input_header pcrextend_header = {
 809         .tag = TPM_TAG_RQU_COMMAND,
 810         .length = cpu_to_be32(34),
 811         .ordinal = TPM_ORD_PCR_EXTEND
 812 };
 813
 814 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
 815 {
 816         struct tpm_cmd_t cmd;
 817         int rc;
 818         struct tpm_chip *chip;
 819
 820         chip = tpm_chip_find_get(chip_num);
 821         if (chip == NULL)
 822                 return -ENODEV;
 823
 824         cmd.header.in = pcrextend_header;
 825         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
 826         memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
 827         rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
 828                           "attempting extend a PCR value");
 829
 830         tpm_chip_put(chip);
 831         return rc;
 832 }
 833 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
 834
 835 /**
 836  * tpm_do_selftest - have the TPM continue its selftest and wait until it
 837  *                   can receive further commands
 838  * @chip: TPM chip to use
 839  *
 840  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
 841  * a TPM error code.
 842  */
 843 int tpm_do_selftest(struct tpm_chip *chip)
 844 {
 845         int rc;
 846         unsigned int loops;
 847         unsigned int delay_msec = 100;
 848         unsigned long duration;
 849         struct tpm_cmd_t cmd;
 850
 851         duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST);
 852
 853         loops = jiffies_to_msecs(duration) / delay_msec;
 854
 855         rc = tpm_continue_selftest(chip);
 856         /* This may fail if there was no TPM driver during a suspend/resume
 857          * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
 858          */
 859         if (rc)
 860                 return rc;
 861
 862         do {
 863                 /* Attempt to read a PCR value */
 864                 cmd.header.in = pcrread_header;
 865                 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(0);
 866                 rc = tpm_transmit(chip, (u8 *) &cmd, READ_PCR_RESULT_SIZE);
 867                 /* Some buggy TPMs will not respond to tpm_tis_ready() for
 868                  * around 300ms while the self test is ongoing, keep trying
 869                  * until the self test duration expires. */
 870                 if (rc == -ETIME) {
 871                         dev_info(chip->dev, HW_ERR "TPM command timed out during continue self test");
 872                         msleep(delay_msec);
 873                         continue;
 874                 }
 875
 876                 if (rc < TPM_HEADER_SIZE)
 877                         return -EFAULT;
 878
 879                 rc = be32_to_cpu(cmd.header.out.return_code);
 880                 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
 881                         dev_info(chip->dev,
 882                                  "TPM is disabled/deactivated (0x%X)\n", rc);
 883                         /* TPM is disabled and/or deactivated; driver can
 884                          * proceed and TPM does handle commands for
 885                          * suspend/resume correctly
 886                          */
 887                         return 0;
 888                 }
 889                 if (rc != TPM_WARN_DOING_SELFTEST)
 890                         return rc;
 891                 msleep(delay_msec);
 892         } while (--loops > 0);
 893
 894         return rc;
 895 }
 896 EXPORT_SYMBOL_GPL(tpm_do_selftest);
 897
 898 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
 899 {
 900         struct tpm_chip *chip;
 901         int rc;
 902
 903         chip = tpm_chip_find_get(chip_num);
 904         if (chip == NULL)
 905                 return -ENODEV;
 906
 907         rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
 908
 909         tpm_chip_put(chip);
 910         return rc;
 911 }
 912 EXPORT_SYMBOL_GPL(tpm_send);
 913
 914 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
 915                       char *buf)
 916 {
 917         cap_t cap;
 918         u8 digest[TPM_DIGEST_SIZE];
 919         ssize_t rc;
 920         int i, j, num_pcrs;
 921         char *str = buf;
 922         struct tpm_chip *chip = dev_get_drvdata(dev);
 923
 924         rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
 925                         "attempting to determine the number of PCRS");
 926         if (rc)
 927                 return 0;
 928
 929         num_pcrs = be32_to_cpu(cap.num_pcrs);
 930         for (i = 0; i < num_pcrs; i++) {
 931                 rc = __tpm_pcr_read(chip, i, digest);
 932                 if (rc)
 933                         break;
 934                 str += sprintf(str, "PCR-%02d: ", i);
 935                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
 936                         str += sprintf(str, "%02X ", digest[j]);
 937                 str += sprintf(str, "\n");
 938         }
 939         return str - buf;
 940 }
 941 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 942
 943 #define  READ_PUBEK_RESULT_SIZE 314
 944 #define TPM_ORD_READPUBEK cpu_to_be32(124)
 945 static struct tpm_input_header tpm_readpubek_header = {
 946         .tag = TPM_TAG_RQU_COMMAND,
 947         .length = cpu_to_be32(30),
 948         .ordinal = TPM_ORD_READPUBEK
 949 };
 950
 951 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
 952                        char *buf)
 953 {
 954         u8 *data;
 955         struct tpm_cmd_t tpm_cmd;
 956         ssize_t err;
 957         int i, rc;
 958         char *str = buf;
 959
 960         struct tpm_chip *chip = dev_get_drvdata(dev);
 961
 962         tpm_cmd.header.in = tpm_readpubek_header;
 963         err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
 964                         "attempting to read the PUBEK");
 965         if (err)
 966                 goto out;
 967
 968         /*
 969            ignore header 10 bytes
 970            algorithm 32 bits (1 == RSA )
 971            encscheme 16 bits
 972            sigscheme 16 bits
 973            parameters (RSA 12->bytes: keybit, #primes, expbit)
 974            keylenbytes 32 bits
 975            256 byte modulus
 976            ignore checksum 20 bytes
 977          */
 978         data = tpm_cmd.params.readpubek_out_buffer;
 979         str +=
 980             sprintf(str,
 981                     "Algorithm: %02X %02X %02X %02X\n"
 982                     "Encscheme: %02X %02X\n"
 983                     "Sigscheme: %02X %02X\n"
 984                     "Parameters: %02X %02X %02X %02X "
 985                     "%02X %02X %02X %02X "
 986                     "%02X %02X %02X %02X\n"
 987                     "Modulus length: %d\n"
 988                     "Modulus:\n",
 989                     data[0], data[1], data[2], data[3],
 990                     data[4], data[5],
 991                     data[6], data[7],
 992                     data[12], data[13], data[14], data[15],
 993                     data[16], data[17], data[18], data[19],
 994                     data[20], data[21], data[22], data[23],
 995                     be32_to_cpu(*((__be32 *) (data + 24))));
 996
 997         for (i = 0; i < 256; i++) {
 998                 str += sprintf(str, "%02X ", data[i + 28]);
 999                 if ((i + 1) % 16 == 0)
1000                         str += sprintf(str, "\n");
1001         }
1002 out:
1003         rc = str - buf;
1004         return rc;
1005 }
1006 EXPORT_SYMBOL_GPL(tpm_show_pubek);
1007
1008
1009 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
1010                       char *buf)
1011 {
1012         cap_t cap;
1013         ssize_t rc;
1014         char *str = buf;
1015
1016         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
1017                         "attempting to determine the manufacturer");
1018         if (rc)
1019                 return 0;
1020         str += sprintf(str, "Manufacturer: 0x%x\n",
1021                        be32_to_cpu(cap.manufacturer_id));
1022
1023         /* Try to get a TPM version 1.2 TPM_CAP_VERSION_INFO */
1024         rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
1025                          "attempting to determine the 1.2 version");
1026         if (!rc) {
1027                 str += sprintf(str,
1028                                "TCG version: %d.%d\nFirmware version: %d.%d\n",
1029                                cap.tpm_version_1_2.Major,
1030                                cap.tpm_version_1_2.Minor,
1031                                cap.tpm_version_1_2.revMajor,
1032                                cap.tpm_version_1_2.revMinor);
1033         } else {
1034                 /* Otherwise just use TPM_STRUCT_VER */
1035                 rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
1036                                 "attempting to determine the 1.1 version");
1037                 if (rc)
1038                         return 0;
1039                 str += sprintf(str,
1040                                "TCG version: %d.%d\nFirmware version: %d.%d\n",
1041                                cap.tpm_version.Major,
1042                                cap.tpm_version.Minor,
1043                                cap.tpm_version.revMajor,
1044                                cap.tpm_version.revMinor);
1045         }
1046
1047         return str - buf;
1048 }
1049 EXPORT_SYMBOL_GPL(tpm_show_caps);
1050
1051 ssize_t tpm_show_durations(struct device *dev, struct device_attribute *attr,
1052                           char *buf)
1053 {
1054         struct tpm_chip *chip = dev_get_drvdata(dev);
1055
1056         if (chip->vendor.duration[TPM_LONG] == 0)
1057                 return 0;
1058
1059         return sprintf(buf, "%d %d %d [%s]\n",
1060                        jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
1061                        jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
1062                        jiffies_to_usecs(chip->vendor.duration[TPM_LONG]),
1063                        chip->vendor.duration_adjusted
1064                        ? "adjusted" : "original");
1065 }
1066 EXPORT_SYMBOL_GPL(tpm_show_durations);
1067
1068 ssize_t tpm_show_timeouts(struct device *dev, struct device_attribute *attr,
1069                           char *buf)
1070 {
1071         struct tpm_chip *chip = dev_get_drvdata(dev);
1072
1073         return sprintf(buf, "%d %d %d %d [%s]\n",
1074                        jiffies_to_usecs(chip->vendor.timeout_a),
1075                        jiffies_to_usecs(chip->vendor.timeout_b),
1076                        jiffies_to_usecs(chip->vendor.timeout_c),
1077                        jiffies_to_usecs(chip->vendor.timeout_d),
1078                        chip->vendor.timeout_adjusted
1079                        ? "adjusted" : "original");
1080 }
1081 EXPORT_SYMBOL_GPL(tpm_show_timeouts);
1082
1083 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
1084                         const char *buf, size_t count)
1085 {
1086         struct tpm_chip *chip = dev_get_drvdata(dev);
1087         if (chip == NULL)
1088                 return 0;
1089
1090         chip->vendor.cancel(chip);
1091         return count;
1092 }
1093 EXPORT_SYMBOL_GPL(tpm_store_cancel);
1094
1095 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
1096                                         bool check_cancel, bool *canceled)
1097 {
1098         u8 status = chip->vendor.status(chip);
1099
1100         *canceled = false;
1101         if ((status & mask) == mask)
1102                 return true;
1103         if (check_cancel && chip->vendor.req_canceled(chip, status)) {
1104                 *canceled = true;
1105                 return true;
1106         }
1107         return false;
1108 }
1109
1110 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
1111                       wait_queue_head_t *queue, bool check_cancel)
1112 {
1113         unsigned long stop;
1114         long rc;
1115         u8 status;
1116         bool canceled = false;
1117
1118         /* check current status */
1119         status = chip->vendor.status(chip);
1120         if ((status & mask) == mask)
1121                 return 0;
1122
1123         stop = jiffies + timeout;
1124
1125         if (chip->vendor.irq) {
1126 again:
1127                 timeout = stop - jiffies;
1128                 if ((long)timeout <= 0)
1129                         return -ETIME;
1130                 rc = wait_event_interruptible_timeout(*queue,
1131                         wait_for_tpm_stat_cond(chip, mask, check_cancel,
1132                                                &canceled),
1133                         timeout);
1134                 if (rc > 0) {
1135                         if (canceled)
1136                                 return -ECANCELED;
1137                         return 0;
1138                 }
1139                 if (rc == -ERESTARTSYS && freezing(current)) {
1140                         clear_thread_flag(TIF_SIGPENDING);
1141                         goto again;
1142                 }
1143         } else {
1144                 do {
1145                         msleep(TPM_TIMEOUT);
1146                         status = chip->vendor.status(chip);
1147                         if ((status & mask) == mask)
1148                                 return 0;
1149                 } while (time_before(jiffies, stop));
1150         }
1151         return -ETIME;
1152 }
1153 EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
1154 /*
1155  * Device file system interface to the TPM
1156  *
1157  * It's assured that the chip will be opened just once,
1158  * by the check of is_open variable, which is protected
1159  * by driver_lock.
1160  */
1161 int tpm_open(struct inode *inode, struct file *file)
1162 {
1163         struct miscdevice *misc = file->private_data;
1164         struct tpm_chip *chip = container_of(misc, struct tpm_chip,
1165                                              vendor.miscdev);
1166
1167         if (test_and_set_bit(0, &chip->is_open)) {
1168                 dev_dbg(chip->dev, "Another process owns this TPM\n");
1169                 return -EBUSY;
1170         }
1171
1172         chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
1173         if (chip->data_buffer == NULL) {
1174                 clear_bit(0, &chip->is_open);
1175                 return -ENOMEM;
1176         }
1177
1178         atomic_set(&chip->data_pending, 0);
1179
1180         file->private_data = chip;
1181         get_device(chip->dev);
1182         return 0;
1183 }
1184 EXPORT_SYMBOL_GPL(tpm_open);
1185
1186 /*
1187  * Called on file close
1188  */
1189 int tpm_release(struct inode *inode, struct file *file)
1190 {
1191         struct tpm_chip *chip = file->private_data;
1192
1193         del_singleshot_timer_sync(&chip->user_read_timer);
1194         flush_work(&chip->work);
1195         file->private_data = NULL;
1196         atomic_set(&chip->data_pending, 0);
1197         kzfree(chip->data_buffer);
1198         clear_bit(0, &chip->is_open);
1199         put_device(chip->dev);
1200         return 0;
1201 }
1202 EXPORT_SYMBOL_GPL(tpm_release);
1203
1204 ssize_t tpm_write(struct file *file, const char __user *buf,
1205                   size_t size, loff_t *off)
1206 {
1207         struct tpm_chip *chip = file->private_data;
1208         size_t in_size = size;
1209         ssize_t out_size;
1210
1211         /* cannot perform a write until the read has cleared
1212            either via tpm_read or a user_read_timer timeout.
1213            This also prevents splitted buffered writes from blocking here.
1214         */
1215         if (atomic_read(&chip->data_pending) != 0)
1216                 return -EBUSY;
1217
1218         if (in_size > TPM_BUFSIZE)
1219                 return -E2BIG;
1220
1221         mutex_lock(&chip->buffer_mutex);
1222
1223         if (copy_from_user
1224             (chip->data_buffer, (void __user *) buf, in_size)) {
1225                 mutex_unlock(&chip->buffer_mutex);
1226                 return -EFAULT;
1227         }
1228
1229         /* atomic tpm command send and result receive */
1230         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1231         if (out_size < 0) {
1232                 mutex_unlock(&chip->buffer_mutex);
1233                 return out_size;
1234         }
1235
1236         atomic_set(&chip->data_pending, out_size);
1237         mutex_unlock(&chip->buffer_mutex);
1238
1239         /* Set a timeout by which the reader must come claim the result */
1240         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1241
1242         return in_size;
1243 }
1244 EXPORT_SYMBOL_GPL(tpm_write);
1245
1246 ssize_t tpm_read(struct file *file, char __user *buf,
1247                  size_t size, loff_t *off)
1248 {
1249         struct tpm_chip *chip = file->private_data;
1250         ssize_t ret_size;
1251         int rc;
1252
1253         del_singleshot_timer_sync(&chip->user_read_timer);
1254         flush_work(&chip->work);
1255         ret_size = atomic_read(&chip->data_pending);
1256         if (ret_size > 0) {     /* relay data */
1257                 ssize_t orig_ret_size = ret_size;
1258                 if (size < ret_size)
1259                         ret_size = size;
1260
1261                 mutex_lock(&chip->buffer_mutex);
1262                 rc = copy_to_user(buf, chip->data_buffer, ret_size);
1263                 memset(chip->data_buffer, 0, orig_ret_size);
1264                 if (rc)
1265                         ret_size = -EFAULT;
1266
1267                 mutex_unlock(&chip->buffer_mutex);
1268         }
1269
1270         atomic_set(&chip->data_pending, 0);
1271
1272         return ret_size;
1273 }
1274 EXPORT_SYMBOL_GPL(tpm_read);
1275
1276 void tpm_remove_hardware(struct device *dev)
1277 {
1278         struct tpm_chip *chip = dev_get_drvdata(dev);
1279
1280         if (chip == NULL) {
1281                 dev_err(dev, "No device data found\n");
1282                 return;
1283         }
1284
1285         spin_lock(&driver_lock);
1286         list_del_rcu(&chip->list);
1287         spin_unlock(&driver_lock);
1288         synchronize_rcu();
1289
1290         misc_deregister(&chip->vendor.miscdev);
1291         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1292         tpm_remove_ppi(&dev->kobj);
1293         tpm_bios_log_teardown(chip->bios_dir);
1294
1295         /* write it this way to be explicit (chip->dev == dev) */
1296         put_device(chip->dev);
1297 }
1298 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1299
1300 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1301 #define SAVESTATE_RESULT_SIZE 10
1302
1303 static struct tpm_input_header savestate_header = {
1304         .tag = TPM_TAG_RQU_COMMAND,
1305         .length = cpu_to_be32(10),
1306         .ordinal = TPM_ORD_SAVESTATE
1307 };
1308
1309 /*
1310  * We are about to suspend. Save the TPM state
1311  * so that it can be restored.
1312  */
1313 int tpm_pm_suspend(struct device *dev)
1314 {
1315         struct tpm_chip *chip = dev_get_drvdata(dev);
1316         struct tpm_cmd_t cmd;
1317         int rc, try;
1318
1319         u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1320
1321         if (chip == NULL)
1322                 return -ENODEV;
1323
1324         /* for buggy tpm, flush pcrs with extend to selected dummy */
1325         if (tpm_suspend_pcr) {
1326                 cmd.header.in = pcrextend_header;
1327                 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1328                 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1329                        TPM_DIGEST_SIZE);
1330                 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1331                                   "extending dummy pcr before suspend");
1332         }
1333
1334         /* now do the actual savestate */
1335         for (try = 0; try < TPM_RETRY; try++) {
1336                 cmd.header.in = savestate_header;
1337                 rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, NULL);
1338
1339                 /*
1340                  * If the TPM indicates that it is too busy to respond to
1341                  * this command then retry before giving up.  It can take
1342                  * several seconds for this TPM to be ready.
1343                  *
1344                  * This can happen if the TPM has already been sent the
1345                  * SaveState command before the driver has loaded.  TCG 1.2
1346                  * specification states that any communication after SaveState
1347                  * may cause the TPM to invalidate previously saved state.
1348                  */
1349                 if (rc != TPM_WARN_RETRY)
1350                         break;
1351                 msleep(TPM_TIMEOUT_RETRY);
1352         }
1353
1354         if (rc)
1355                 dev_err(chip->dev,
1356                         "Error (%d) sending savestate before suspend\n", rc);
1357         else if (try > 0)
1358                 dev_warn(chip->dev, "TPM savestate took %dms\n",
1359                          try * TPM_TIMEOUT_RETRY);
1360
1361         return rc;
1362 }
1363 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1364
1365 /*
1366  * Resume from a power safe. The BIOS already restored
1367  * the TPM state.
1368  */
1369 int tpm_pm_resume(struct device *dev)
1370 {
1371         struct tpm_chip *chip = dev_get_drvdata(dev);
1372
1373         if (chip == NULL)
1374                 return -ENODEV;
1375
1376         return 0;
1377 }
1378 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1379
1380 #define TPM_GETRANDOM_RESULT_SIZE       18
1381 static struct tpm_input_header tpm_getrandom_header = {
1382         .tag = TPM_TAG_RQU_COMMAND,
1383         .length = cpu_to_be32(14),
1384         .ordinal = TPM_ORD_GET_RANDOM
1385 };
1386
1387 /**
1388  * tpm_get_random() - Get random bytes from the tpm's RNG
1389  * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1390  * @out: destination buffer for the random bytes
1391  * @max: the max number of bytes to write to @out
1392  *
1393  * Returns < 0 on error and the number of bytes read on success
1394  */
1395 int tpm_get_random(u32 chip_num, u8 *out, size_t max)
1396 {
1397         struct tpm_chip *chip;
1398         struct tpm_cmd_t tpm_cmd;
1399         u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA);
1400         int err, total = 0, retries = 5;
1401         u8 *dest = out;
1402
1403         chip = tpm_chip_find_get(chip_num);
1404         if (chip == NULL)
1405                 return -ENODEV;
1406
1407         if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
1408                 return -EINVAL;
1409
1410         do {
1411                 tpm_cmd.header.in = tpm_getrandom_header;
1412                 tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
1413
1414                 err = transmit_cmd(chip, &tpm_cmd,
1415                                    TPM_GETRANDOM_RESULT_SIZE + num_bytes,
1416                                    "attempting get random");
1417                 if (err)
1418                         break;
1419
1420                 recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
1421                 memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
1422
1423                 dest += recd;
1424                 total += recd;
1425                 num_bytes -= recd;
1426         } while (retries-- && total < max);
1427
1428         return total ? total : -EIO;
1429 }
1430 EXPORT_SYMBOL_GPL(tpm_get_random);
1431
1432 /* In case vendor provided release function, call it too.*/
1433
1434 void tpm_dev_vendor_release(struct tpm_chip *chip)
1435 {
1436         if (!chip)
1437                 return;
1438
1439         if (chip->vendor.release)
1440                 chip->vendor.release(chip->dev);
1441
1442         clear_bit(chip->dev_num, dev_mask);
1443 }
1444 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1445
1446
1447 /*
1448  * Once all references to platform device are down to 0,
1449  * release all allocated structures.
1450  */
1451 void tpm_dev_release(struct device *dev)
1452 {
1453         struct tpm_chip *chip = dev_get_drvdata(dev);
1454
1455         if (!chip)
1456                 return;
1457
1458         tpm_dev_vendor_release(chip);
1459
1460         chip->release(dev);
1461         kfree(chip);
1462 }
1463 EXPORT_SYMBOL_GPL(tpm_dev_release);
1464
1465 /*
1466  * Called from tpm_<specific>.c probe function only for devices
1467  * the driver has determined it should claim.  Prior to calling
1468  * this function the specific probe function has called pci_enable_device
1469  * upon errant exit from this function specific probe function should call
1470  * pci_disable_device
1471  */
1472 struct tpm_chip *tpm_register_hardware(struct device *dev,
1473                                         const struct tpm_vendor_specific *entry)
1474 {
1475         struct tpm_chip *chip;
1476
1477         /* Driver specific per-device data */
1478         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1479
1480         if (chip == NULL)
1481                 return NULL;
1482
1483         mutex_init(&chip->buffer_mutex);
1484         mutex_init(&chip->tpm_mutex);
1485         INIT_LIST_HEAD(&chip->list);
1486
1487         INIT_WORK(&chip->work, timeout_work);
1488
1489         setup_timer(&chip->user_read_timer, user_reader_timeout,
1490                         (unsigned long)chip);
1491
1492         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1493
1494         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1495
1496         if (chip->dev_num >= TPM_NUM_DEVICES) {
1497                 dev_err(dev, "No available tpm device numbers\n");
1498                 goto out_free;
1499         } else if (chip->dev_num == 0)
1500                 chip->vendor.miscdev.minor = TPM_MINOR;
1501         else
1502                 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1503
1504         set_bit(chip->dev_num, dev_mask);
1505
1506         scnprintf(chip->devname, sizeof(chip->devname), "%s%d", "tpm",
1507                   chip->dev_num);
1508         chip->vendor.miscdev.name = chip->devname;
1509
1510         chip->vendor.miscdev.parent = dev;
1511         chip->dev = get_device(dev);
1512         chip->release = dev->release;
1513         dev->release = tpm_dev_release;
1514         dev_set_drvdata(dev, chip);
1515
1516         if (misc_register(&chip->vendor.miscdev)) {
1517                 dev_err(chip->dev,
1518                         "unable to misc_register %s, minor %d\n",
1519                         chip->vendor.miscdev.name,
1520                         chip->vendor.miscdev.minor);
1521                 goto put_device;
1522         }
1523
1524         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1525                 misc_deregister(&chip->vendor.miscdev);
1526                 goto put_device;
1527         }
1528
1529         if (tpm_add_ppi(&dev->kobj)) {
1530                 misc_deregister(&chip->vendor.miscdev);
1531                 goto put_device;
1532         }
1533
1534         chip->bios_dir = tpm_bios_log_setup(chip->devname);
1535
1536         /* Make chip available */
1537         spin_lock(&driver_lock);
1538         list_add_rcu(&chip->list, &tpm_chip_list);
1539         spin_unlock(&driver_lock);
1540
1541         return chip;
1542
1543 put_device:
1544         put_device(chip->dev);
1545 out_free:
1546         kfree(chip);
1547         return NULL;
1548 }
1549 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1550
1551 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1552 MODULE_DESCRIPTION("TPM Driver");
1553 MODULE_VERSION("2.0");
1554 MODULE_LICENSE("GPL");