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/mutex.h>
  28 #include <linux/spinlock.h>
  29
  30 #include "tpm.h"
  31
  32 enum tpm_const {
  33         TPM_MINOR = 224,        /* officially assigned */
  34         TPM_BUFSIZE = 2048,
  35         TPM_NUM_DEVICES = 256,
  36 };
  37
  38 enum tpm_duration {
  39         TPM_SHORT = 0,
  40         TPM_MEDIUM = 1,
  41         TPM_LONG = 2,
  42         TPM_UNDEFINED,
  43 };
  44
  45 #define TPM_MAX_ORDINAL 243
  46 #define TPM_MAX_PROTECTED_ORDINAL 12
  47 #define TPM_PROTECTED_ORDINAL_MASK 0xFF
  48
  49 static LIST_HEAD(tpm_chip_list);
  50 static DEFINE_SPINLOCK(driver_lock);
  51 static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
  52
  53 /*
  54  * Array with one entry per ordinal defining the maximum amount
  55  * of time the chip could take to return the result.  The ordinal
  56  * designation of short, medium or long is defined in a table in
  57  * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
  58  * values of the SHORT, MEDIUM, and LONG durations are retrieved
  59  * from the chip during initialization with a call to tpm_get_timeouts.
  60  */
  61 static const u8 tpm_protected_ordinal_duration[TPM_MAX_PROTECTED_ORDINAL] = {
  62         TPM_UNDEFINED,          /* 0 */
  63         TPM_UNDEFINED,
  64         TPM_UNDEFINED,
  65         TPM_UNDEFINED,
  66         TPM_UNDEFINED,
  67         TPM_UNDEFINED,          /* 5 */
  68         TPM_UNDEFINED,
  69         TPM_UNDEFINED,
  70         TPM_UNDEFINED,
  71         TPM_UNDEFINED,
  72         TPM_SHORT,              /* 10 */
  73         TPM_SHORT,
  74 };
  75
  76 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
  77         TPM_UNDEFINED,          /* 0 */
  78         TPM_UNDEFINED,
  79         TPM_UNDEFINED,
  80         TPM_UNDEFINED,
  81         TPM_UNDEFINED,
  82         TPM_UNDEFINED,          /* 5 */
  83         TPM_UNDEFINED,
  84         TPM_UNDEFINED,
  85         TPM_UNDEFINED,
  86         TPM_UNDEFINED,
  87         TPM_SHORT,              /* 10 */
  88         TPM_SHORT,
  89         TPM_MEDIUM,
  90         TPM_LONG,
  91         TPM_LONG,
  92         TPM_MEDIUM,             /* 15 */
  93         TPM_SHORT,
  94         TPM_SHORT,
  95         TPM_MEDIUM,
  96         TPM_LONG,
  97         TPM_SHORT,              /* 20 */
  98         TPM_SHORT,
  99         TPM_MEDIUM,
 100         TPM_MEDIUM,
 101         TPM_MEDIUM,
 102         TPM_SHORT,              /* 25 */
 103         TPM_SHORT,
 104         TPM_MEDIUM,
 105         TPM_SHORT,
 106         TPM_SHORT,
 107         TPM_MEDIUM,             /* 30 */
 108         TPM_LONG,
 109         TPM_MEDIUM,
 110         TPM_SHORT,
 111         TPM_SHORT,
 112         TPM_SHORT,              /* 35 */
 113         TPM_MEDIUM,
 114         TPM_MEDIUM,
 115         TPM_UNDEFINED,
 116         TPM_UNDEFINED,
 117         TPM_MEDIUM,             /* 40 */
 118         TPM_LONG,
 119         TPM_MEDIUM,
 120         TPM_SHORT,
 121         TPM_SHORT,
 122         TPM_SHORT,              /* 45 */
 123         TPM_SHORT,
 124         TPM_SHORT,
 125         TPM_SHORT,
 126         TPM_LONG,
 127         TPM_MEDIUM,             /* 50 */
 128         TPM_MEDIUM,
 129         TPM_UNDEFINED,
 130         TPM_UNDEFINED,
 131         TPM_UNDEFINED,
 132         TPM_UNDEFINED,          /* 55 */
 133         TPM_UNDEFINED,
 134         TPM_UNDEFINED,
 135         TPM_UNDEFINED,
 136         TPM_UNDEFINED,
 137         TPM_MEDIUM,             /* 60 */
 138         TPM_MEDIUM,
 139         TPM_MEDIUM,
 140         TPM_SHORT,
 141         TPM_SHORT,
 142         TPM_MEDIUM,             /* 65 */
 143         TPM_UNDEFINED,
 144         TPM_UNDEFINED,
 145         TPM_UNDEFINED,
 146         TPM_UNDEFINED,
 147         TPM_SHORT,              /* 70 */
 148         TPM_SHORT,
 149         TPM_UNDEFINED,
 150         TPM_UNDEFINED,
 151         TPM_UNDEFINED,
 152         TPM_UNDEFINED,          /* 75 */
 153         TPM_UNDEFINED,
 154         TPM_UNDEFINED,
 155         TPM_UNDEFINED,
 156         TPM_UNDEFINED,
 157         TPM_LONG,               /* 80 */
 158         TPM_UNDEFINED,
 159         TPM_MEDIUM,
 160         TPM_LONG,
 161         TPM_SHORT,
 162         TPM_UNDEFINED,          /* 85 */
 163         TPM_UNDEFINED,
 164         TPM_UNDEFINED,
 165         TPM_UNDEFINED,
 166         TPM_UNDEFINED,
 167         TPM_SHORT,              /* 90 */
 168         TPM_SHORT,
 169         TPM_SHORT,
 170         TPM_SHORT,
 171         TPM_SHORT,
 172         TPM_UNDEFINED,          /* 95 */
 173         TPM_UNDEFINED,
 174         TPM_UNDEFINED,
 175         TPM_UNDEFINED,
 176         TPM_UNDEFINED,
 177         TPM_MEDIUM,             /* 100 */
 178         TPM_SHORT,
 179         TPM_SHORT,
 180         TPM_UNDEFINED,
 181         TPM_UNDEFINED,
 182         TPM_UNDEFINED,          /* 105 */
 183         TPM_UNDEFINED,
 184         TPM_UNDEFINED,
 185         TPM_UNDEFINED,
 186         TPM_UNDEFINED,
 187         TPM_SHORT,              /* 110 */
 188         TPM_SHORT,
 189         TPM_SHORT,
 190         TPM_SHORT,
 191         TPM_SHORT,
 192         TPM_SHORT,              /* 115 */
 193         TPM_SHORT,
 194         TPM_SHORT,
 195         TPM_UNDEFINED,
 196         TPM_UNDEFINED,
 197         TPM_LONG,               /* 120 */
 198         TPM_LONG,
 199         TPM_MEDIUM,
 200         TPM_UNDEFINED,
 201         TPM_SHORT,
 202         TPM_SHORT,              /* 125 */
 203         TPM_SHORT,
 204         TPM_LONG,
 205         TPM_SHORT,
 206         TPM_SHORT,
 207         TPM_SHORT,              /* 130 */
 208         TPM_MEDIUM,
 209         TPM_UNDEFINED,
 210         TPM_SHORT,
 211         TPM_MEDIUM,
 212         TPM_UNDEFINED,          /* 135 */
 213         TPM_UNDEFINED,
 214         TPM_UNDEFINED,
 215         TPM_UNDEFINED,
 216         TPM_UNDEFINED,
 217         TPM_SHORT,              /* 140 */
 218         TPM_SHORT,
 219         TPM_UNDEFINED,
 220         TPM_UNDEFINED,
 221         TPM_UNDEFINED,
 222         TPM_UNDEFINED,          /* 145 */
 223         TPM_UNDEFINED,
 224         TPM_UNDEFINED,
 225         TPM_UNDEFINED,
 226         TPM_UNDEFINED,
 227         TPM_SHORT,              /* 150 */
 228         TPM_MEDIUM,
 229         TPM_MEDIUM,
 230         TPM_SHORT,
 231         TPM_SHORT,
 232         TPM_UNDEFINED,          /* 155 */
 233         TPM_UNDEFINED,
 234         TPM_UNDEFINED,
 235         TPM_UNDEFINED,
 236         TPM_UNDEFINED,
 237         TPM_SHORT,              /* 160 */
 238         TPM_SHORT,
 239         TPM_SHORT,
 240         TPM_SHORT,
 241         TPM_UNDEFINED,
 242         TPM_UNDEFINED,          /* 165 */
 243         TPM_UNDEFINED,
 244         TPM_UNDEFINED,
 245         TPM_UNDEFINED,
 246         TPM_UNDEFINED,
 247         TPM_LONG,               /* 170 */
 248         TPM_UNDEFINED,
 249         TPM_UNDEFINED,
 250         TPM_UNDEFINED,
 251         TPM_UNDEFINED,
 252         TPM_UNDEFINED,          /* 175 */
 253         TPM_UNDEFINED,
 254         TPM_UNDEFINED,
 255         TPM_UNDEFINED,
 256         TPM_UNDEFINED,
 257         TPM_MEDIUM,             /* 180 */
 258         TPM_SHORT,
 259         TPM_MEDIUM,
 260         TPM_MEDIUM,
 261         TPM_MEDIUM,
 262         TPM_MEDIUM,             /* 185 */
 263         TPM_SHORT,
 264         TPM_UNDEFINED,
 265         TPM_UNDEFINED,
 266         TPM_UNDEFINED,
 267         TPM_UNDEFINED,          /* 190 */
 268         TPM_UNDEFINED,
 269         TPM_UNDEFINED,
 270         TPM_UNDEFINED,
 271         TPM_UNDEFINED,
 272         TPM_UNDEFINED,          /* 195 */
 273         TPM_UNDEFINED,
 274         TPM_UNDEFINED,
 275         TPM_UNDEFINED,
 276         TPM_UNDEFINED,
 277         TPM_SHORT,              /* 200 */
 278         TPM_UNDEFINED,
 279         TPM_UNDEFINED,
 280         TPM_UNDEFINED,
 281         TPM_SHORT,
 282         TPM_SHORT,              /* 205 */
 283         TPM_SHORT,
 284         TPM_SHORT,
 285         TPM_SHORT,
 286         TPM_SHORT,
 287         TPM_MEDIUM,             /* 210 */
 288         TPM_UNDEFINED,
 289         TPM_MEDIUM,
 290         TPM_MEDIUM,
 291         TPM_MEDIUM,
 292         TPM_UNDEFINED,          /* 215 */
 293         TPM_MEDIUM,
 294         TPM_UNDEFINED,
 295         TPM_UNDEFINED,
 296         TPM_SHORT,
 297         TPM_SHORT,              /* 220 */
 298         TPM_SHORT,
 299         TPM_SHORT,
 300         TPM_SHORT,
 301         TPM_SHORT,
 302         TPM_UNDEFINED,          /* 225 */
 303         TPM_UNDEFINED,
 304         TPM_UNDEFINED,
 305         TPM_UNDEFINED,
 306         TPM_UNDEFINED,
 307         TPM_SHORT,              /* 230 */
 308         TPM_LONG,
 309         TPM_MEDIUM,
 310         TPM_UNDEFINED,
 311         TPM_UNDEFINED,
 312         TPM_UNDEFINED,          /* 235 */
 313         TPM_UNDEFINED,
 314         TPM_UNDEFINED,
 315         TPM_UNDEFINED,
 316         TPM_UNDEFINED,
 317         TPM_SHORT,              /* 240 */
 318         TPM_UNDEFINED,
 319         TPM_MEDIUM,
 320 };
 321
 322 static void user_reader_timeout(unsigned long ptr)
 323 {
 324         struct tpm_chip *chip = (struct tpm_chip *) ptr;
 325
 326         schedule_work(&chip->work);
 327 }
 328
 329 static void timeout_work(struct work_struct *work)
 330 {
 331         struct tpm_chip *chip = container_of(work, struct tpm_chip, work);
 332
 333         mutex_lock(&chip->buffer_mutex);
 334         atomic_set(&chip->data_pending, 0);
 335         memset(chip->data_buffer, 0, TPM_BUFSIZE);
 336         mutex_unlock(&chip->buffer_mutex);
 337 }
 338
 339 /*
 340  * Returns max number of jiffies to wait
 341  */
 342 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
 343                                            u32 ordinal)
 344 {
 345         int duration_idx = TPM_UNDEFINED;
 346         int duration = 0;
 347
 348         if (ordinal < TPM_MAX_ORDINAL)
 349                 duration_idx = tpm_ordinal_duration[ordinal];
 350         else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
 351                  TPM_MAX_PROTECTED_ORDINAL)
 352                 duration_idx =
 353                     tpm_protected_ordinal_duration[ordinal &
 354                                                    TPM_PROTECTED_ORDINAL_MASK];
 355
 356         if (duration_idx != TPM_UNDEFINED)
 357                 duration = chip->vendor.duration[duration_idx];
 358         if (duration <= 0)
 359                 return 2 * 60 * HZ;
 360         else
 361                 return duration;
 362 }
 363 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 364
 365 /*
 366  * Internal kernel interface to transmit TPM commands
 367  */
 368 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
 369                             size_t bufsiz)
 370 {
 371         ssize_t rc;
 372         u32 count, ordinal;
 373         unsigned long stop;
 374
 375         count = be32_to_cpu(*((__be32 *) (buf + 2)));
 376         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
 377         if (count == 0)
 378                 return -ENODATA;
 379         if (count > bufsiz) {
 380                 dev_err(chip->dev,
 381                         "invalid count value %x %zx \n", count, bufsiz);
 382                 return -E2BIG;
 383         }
 384
 385         mutex_lock(&chip->tpm_mutex);
 386
 387         if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
 388                 dev_err(chip->dev,
 389                         "tpm_transmit: tpm_send: error %zd\n", rc);
 390                 goto out;
 391         }
 392
 393         if (chip->vendor.irq)
 394                 goto out_recv;
 395
 396         stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
 397         do {
 398                 u8 status = chip->vendor.status(chip);
 399                 if ((status & chip->vendor.req_complete_mask) ==
 400                     chip->vendor.req_complete_val)
 401                         goto out_recv;
 402
 403                 if ((status == chip->vendor.req_canceled)) {
 404                         dev_err(chip->dev, "Operation Canceled\n");
 405                         rc = -ECANCELED;
 406                         goto out;
 407                 }
 408
 409                 msleep(TPM_TIMEOUT);    /* CHECK */
 410                 rmb();
 411         } while (time_before(jiffies, stop));
 412
 413         chip->vendor.cancel(chip);
 414         dev_err(chip->dev, "Operation Timed out\n");
 415         rc = -ETIME;
 416         goto out;
 417
 418 out_recv:
 419         rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
 420         if (rc < 0)
 421                 dev_err(chip->dev,
 422                         "tpm_transmit: tpm_recv: error %zd\n", rc);
 423 out:
 424         mutex_unlock(&chip->tpm_mutex);
 425         return rc;
 426 }
 427
 428 #define TPM_DIGEST_SIZE 20
 429 #define TPM_ERROR_SIZE 10
 430 #define TPM_RET_CODE_IDX 6
 431
 432 enum tpm_capabilities {
 433         TPM_CAP_FLAG = cpu_to_be32(4),
 434         TPM_CAP_PROP = cpu_to_be32(5),
 435         CAP_VERSION_1_1 = cpu_to_be32(0x06),
 436         CAP_VERSION_1_2 = cpu_to_be32(0x1A)
 437 };
 438
 439 enum tpm_sub_capabilities {
 440         TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
 441         TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
 442         TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
 443         TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
 444         TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
 445         TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
 446         TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
 447
 448 };
 449
 450 static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
 451                             int len, const char *desc)
 452 {
 453         int err;
 454
 455         len = tpm_transmit(chip,(u8 *) cmd, len);
 456         if (len <  0)
 457                 return len;
 458         if (len == TPM_ERROR_SIZE) {
 459                 err = be32_to_cpu(cmd->header.out.return_code);
 460                 dev_dbg(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
 461                 return err;
 462         }
 463         return 0;
 464 }
 465
 466 #define TPM_INTERNAL_RESULT_SIZE 200
 467 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
 468 #define TPM_ORD_GET_CAP cpu_to_be32(101)
 469
 470 static const struct tpm_input_header tpm_getcap_header = {
 471         .tag = TPM_TAG_RQU_COMMAND,
 472         .length = cpu_to_be32(22),
 473         .ordinal = TPM_ORD_GET_CAP
 474 };
 475
 476 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
 477                    const char *desc)
 478 {
 479         struct tpm_cmd_t tpm_cmd;
 480         int rc;
 481         struct tpm_chip *chip = dev_get_drvdata(dev);
 482
 483         tpm_cmd.header.in = tpm_getcap_header;
 484         if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
 485                 tpm_cmd.params.getcap_in.cap = subcap_id;
 486                 /*subcap field not necessary */
 487                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
 488                 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
 489         } else {
 490                 if (subcap_id == TPM_CAP_FLAG_PERM ||
 491                     subcap_id == TPM_CAP_FLAG_VOL)
 492                         tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
 493                 else
 494                         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 495                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 496                 tpm_cmd.params.getcap_in.subcap = subcap_id;
 497         }
 498         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
 499         if (!rc)
 500                 *cap = tpm_cmd.params.getcap_out.cap;
 501         return rc;
 502 }
 503
 504 void tpm_gen_interrupt(struct tpm_chip *chip)
 505 {
 506         struct  tpm_cmd_t tpm_cmd;
 507         ssize_t rc;
 508
 509         tpm_cmd.header.in = tpm_getcap_header;
 510         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 511         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 512         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 513
 514         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 515                         "attempting to determine the timeouts");
 516 }
 517 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
 518
 519 void tpm_get_timeouts(struct tpm_chip *chip)
 520 {
 521         struct tpm_cmd_t tpm_cmd;
 522         struct timeout_t *timeout_cap;
 523         struct duration_t *duration_cap;
 524         ssize_t rc;
 525         u32 timeout;
 526
 527         tpm_cmd.header.in = tpm_getcap_header;
 528         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 529         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 530         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 531
 532         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 533                         "attempting to determine the timeouts");
 534         if (rc)
 535                 goto duration;
 536
 537         if (be32_to_cpu(tpm_cmd.header.out.length)
 538             != 4 * sizeof(u32))
 539                 goto duration;
 540
 541         timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
 542         /* Don't overwrite default if value is 0 */
 543         timeout = be32_to_cpu(timeout_cap->a);
 544         if (timeout)
 545                 chip->vendor.timeout_a = usecs_to_jiffies(timeout);
 546         timeout = be32_to_cpu(timeout_cap->b);
 547         if (timeout)
 548                 chip->vendor.timeout_b = usecs_to_jiffies(timeout);
 549         timeout = be32_to_cpu(timeout_cap->c);
 550         if (timeout)
 551                 chip->vendor.timeout_c = usecs_to_jiffies(timeout);
 552         timeout = be32_to_cpu(timeout_cap->d);
 553         if (timeout)
 554                 chip->vendor.timeout_d = usecs_to_jiffies(timeout);
 555
 556 duration:
 557         tpm_cmd.header.in = tpm_getcap_header;
 558         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 559         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 560         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
 561
 562         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 563                         "attempting to determine the durations");
 564         if (rc)
 565                 return;
 566
 567         if (be32_to_cpu(tpm_cmd.header.out.return_code)
 568             != 3 * sizeof(u32))
 569                 return;
 570         duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
 571         chip->vendor.duration[TPM_SHORT] =
 572             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
 573         /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
 574          * value wrong and apparently reports msecs rather than usecs. So we
 575          * fix up the resulting too-small TPM_SHORT value to make things work.
 576          */
 577         if (chip->vendor.duration[TPM_SHORT] < (HZ/100))
 578                 chip->vendor.duration[TPM_SHORT] = HZ;
 579
 580         chip->vendor.duration[TPM_MEDIUM] =
 581             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
 582         chip->vendor.duration[TPM_LONG] =
 583             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
 584 }
 585 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
 586
 587 void tpm_continue_selftest(struct tpm_chip *chip)
 588 {
 589         u8 data[] = {
 590                 0, 193,                 /* TPM_TAG_RQU_COMMAND */
 591                 0, 0, 0, 10,            /* length */
 592                 0, 0, 0, 83,            /* TPM_ORD_GetCapability */
 593         };
 594
 595         tpm_transmit(chip, data, sizeof(data));
 596 }
 597 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
 598
 599 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
 600                         char *buf)
 601 {
 602         cap_t cap;
 603         ssize_t rc;
 604
 605         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 606                          "attempting to determine the permanent enabled state");
 607         if (rc)
 608                 return 0;
 609
 610         rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
 611         return rc;
 612 }
 613 EXPORT_SYMBOL_GPL(tpm_show_enabled);
 614
 615 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
 616                         char *buf)
 617 {
 618         cap_t cap;
 619         ssize_t rc;
 620
 621         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 622                          "attempting to determine the permanent active state");
 623         if (rc)
 624                 return 0;
 625
 626         rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
 627         return rc;
 628 }
 629 EXPORT_SYMBOL_GPL(tpm_show_active);
 630
 631 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
 632                         char *buf)
 633 {
 634         cap_t cap;
 635         ssize_t rc;
 636
 637         rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
 638                          "attempting to determine the owner state");
 639         if (rc)
 640                 return 0;
 641
 642         rc = sprintf(buf, "%d\n", cap.owned);
 643         return rc;
 644 }
 645 EXPORT_SYMBOL_GPL(tpm_show_owned);
 646
 647 ssize_t tpm_show_temp_deactivated(struct device * dev,
 648                                 struct device_attribute * attr, char *buf)
 649 {
 650         cap_t cap;
 651         ssize_t rc;
 652
 653         rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
 654                          "attempting to determine the temporary state");
 655         if (rc)
 656                 return 0;
 657
 658         rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
 659         return rc;
 660 }
 661 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
 662
 663 /*
 664  * tpm_chip_find_get - return tpm_chip for given chip number
 665  */
 666 static struct tpm_chip *tpm_chip_find_get(int chip_num)
 667 {
 668         struct tpm_chip *pos, *chip = NULL;
 669
 670         rcu_read_lock();
 671         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
 672                 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
 673                         continue;
 674
 675                 if (try_module_get(pos->dev->driver->owner)) {
 676                         chip = pos;
 677                         break;
 678                 }
 679         }
 680         rcu_read_unlock();
 681         return chip;
 682 }
 683
 684 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
 685 #define READ_PCR_RESULT_SIZE 30
 686 static struct tpm_input_header pcrread_header = {
 687         .tag = TPM_TAG_RQU_COMMAND,
 688         .length = cpu_to_be32(14),
 689         .ordinal = TPM_ORDINAL_PCRREAD
 690 };
 691
 692 int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 693 {
 694         int rc;
 695         struct tpm_cmd_t cmd;
 696
 697         cmd.header.in = pcrread_header;
 698         cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
 699         BUG_ON(cmd.header.in.length > READ_PCR_RESULT_SIZE);
 700         rc = transmit_cmd(chip, &cmd, cmd.header.in.length,
 701                           "attempting to read a pcr value");
 702
 703         if (rc == 0)
 704                 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
 705                        TPM_DIGEST_SIZE);
 706         return rc;
 707 }
 708
 709 /**
 710  * tpm_pcr_read - read a pcr value
 711  * @chip_num:   tpm idx # or ANY
 712  * @pcr_idx:    pcr idx to retrieve
 713  * @res_buf:    TPM_PCR value
 714  *              size of res_buf is 20 bytes (or NULL if you don't care)
 715  *
 716  * The TPM driver should be built-in, but for whatever reason it
 717  * isn't, protect against the chip disappearing, by incrementing
 718  * the module usage count.
 719  */
 720 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
 721 {
 722         struct tpm_chip *chip;
 723         int rc;
 724
 725         chip = tpm_chip_find_get(chip_num);
 726         if (chip == NULL)
 727                 return -ENODEV;
 728         rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
 729         module_put(chip->dev->driver->owner);
 730         return rc;
 731 }
 732 EXPORT_SYMBOL_GPL(tpm_pcr_read);
 733
 734 /**
 735  * tpm_pcr_extend - extend pcr value with hash
 736  * @chip_num:   tpm idx # or AN&
 737  * @pcr_idx:    pcr idx to extend
 738  * @hash:       hash value used to extend pcr value
 739  *
 740  * The TPM driver should be built-in, but for whatever reason it
 741  * isn't, protect against the chip disappearing, by incrementing
 742  * the module usage count.
 743  */
 744 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
 745 #define EXTEND_PCR_RESULT_SIZE 34
 746 static struct tpm_input_header pcrextend_header = {
 747         .tag = TPM_TAG_RQU_COMMAND,
 748         .length = cpu_to_be32(34),
 749         .ordinal = TPM_ORD_PCR_EXTEND
 750 };
 751
 752 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
 753 {
 754         struct tpm_cmd_t cmd;
 755         int rc;
 756         struct tpm_chip *chip;
 757
 758         chip = tpm_chip_find_get(chip_num);
 759         if (chip == NULL)
 760                 return -ENODEV;
 761
 762         cmd.header.in = pcrextend_header;
 763         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
 764         memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
 765         rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
 766                           "attempting extend a PCR value");
 767
 768         module_put(chip->dev->driver->owner);
 769         return rc;
 770 }
 771 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
 772
 773 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
 774                       char *buf)
 775 {
 776         cap_t cap;
 777         u8 digest[TPM_DIGEST_SIZE];
 778         ssize_t rc;
 779         int i, j, num_pcrs;
 780         char *str = buf;
 781         struct tpm_chip *chip = dev_get_drvdata(dev);
 782
 783         rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
 784                         "attempting to determine the number of PCRS");
 785         if (rc)
 786                 return 0;
 787
 788         num_pcrs = be32_to_cpu(cap.num_pcrs);
 789         for (i = 0; i < num_pcrs; i++) {
 790                 rc = __tpm_pcr_read(chip, i, digest);
 791                 if (rc)
 792                         break;
 793                 str += sprintf(str, "PCR-%02d: ", i);
 794                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
 795                         str += sprintf(str, "%02X ", digest[j]);
 796                 str += sprintf(str, "\n");
 797         }
 798         return str - buf;
 799 }
 800 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 801
 802 #define  READ_PUBEK_RESULT_SIZE 314
 803 #define TPM_ORD_READPUBEK cpu_to_be32(124)
 804 struct tpm_input_header tpm_readpubek_header = {
 805         .tag = TPM_TAG_RQU_COMMAND,
 806         .length = cpu_to_be32(30),
 807         .ordinal = TPM_ORD_READPUBEK
 808 };
 809
 810 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
 811                        char *buf)
 812 {
 813         u8 *data;
 814         struct tpm_cmd_t tpm_cmd;
 815         ssize_t err;
 816         int i, rc;
 817         char *str = buf;
 818
 819         struct tpm_chip *chip = dev_get_drvdata(dev);
 820
 821         tpm_cmd.header.in = tpm_readpubek_header;
 822         err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
 823                         "attempting to read the PUBEK");
 824         if (err)
 825                 goto out;
 826
 827         /*
 828            ignore header 10 bytes
 829            algorithm 32 bits (1 == RSA )
 830            encscheme 16 bits
 831            sigscheme 16 bits
 832            parameters (RSA 12->bytes: keybit, #primes, expbit)
 833            keylenbytes 32 bits
 834            256 byte modulus
 835            ignore checksum 20 bytes
 836          */
 837         data = tpm_cmd.params.readpubek_out_buffer;
 838         str +=
 839             sprintf(str,
 840                     "Algorithm: %02X %02X %02X %02X\nEncscheme: %02X %02X\n"
 841                     "Sigscheme: %02X %02X\nParameters: %02X %02X %02X %02X"
 842                     " %02X %02X %02X %02X %02X %02X %02X %02X\n"
 843                     "Modulus length: %d\nModulus: \n",
 844                     data[10], data[11], data[12], data[13], data[14],
 845                     data[15], data[16], data[17], data[22], data[23],
 846                     data[24], data[25], data[26], data[27], data[28],
 847                     data[29], data[30], data[31], data[32], data[33],
 848                     be32_to_cpu(*((__be32 *) (data + 34))));
 849
 850         for (i = 0; i < 256; i++) {
 851                 str += sprintf(str, "%02X ", data[i + 38]);
 852                 if ((i + 1) % 16 == 0)
 853                         str += sprintf(str, "\n");
 854         }
 855 out:
 856         rc = str - buf;
 857         return rc;
 858 }
 859 EXPORT_SYMBOL_GPL(tpm_show_pubek);
 860
 861
 862 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
 863                       char *buf)
 864 {
 865         cap_t cap;
 866         ssize_t rc;
 867         char *str = buf;
 868
 869         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
 870                         "attempting to determine the manufacturer");
 871         if (rc)
 872                 return 0;
 873         str += sprintf(str, "Manufacturer: 0x%x\n",
 874                        be32_to_cpu(cap.manufacturer_id));
 875
 876         rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
 877                         "attempting to determine the 1.1 version");
 878         if (rc)
 879                 return 0;
 880         str += sprintf(str,
 881                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
 882                        cap.tpm_version.Major, cap.tpm_version.Minor,
 883                        cap.tpm_version.revMajor, cap.tpm_version.revMinor);
 884         return str - buf;
 885 }
 886 EXPORT_SYMBOL_GPL(tpm_show_caps);
 887
 888 ssize_t tpm_show_caps_1_2(struct device * dev,
 889                           struct device_attribute * attr, char *buf)
 890 {
 891         cap_t cap;
 892         ssize_t rc;
 893         char *str = buf;
 894
 895         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
 896                         "attempting to determine the manufacturer");
 897         if (rc)
 898                 return 0;
 899         str += sprintf(str, "Manufacturer: 0x%x\n",
 900                        be32_to_cpu(cap.manufacturer_id));
 901         rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
 902                          "attempting to determine the 1.2 version");
 903         if (rc)
 904                 return 0;
 905         str += sprintf(str,
 906                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
 907                        cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
 908                        cap.tpm_version_1_2.revMajor,
 909                        cap.tpm_version_1_2.revMinor);
 910         return str - buf;
 911 }
 912 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
 913
 914 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
 915                         const char *buf, size_t count)
 916 {
 917         struct tpm_chip *chip = dev_get_drvdata(dev);
 918         if (chip == NULL)
 919                 return 0;
 920
 921         chip->vendor.cancel(chip);
 922         return count;
 923 }
 924 EXPORT_SYMBOL_GPL(tpm_store_cancel);
 925
 926 /*
 927  * Device file system interface to the TPM
 928  *
 929  * It's assured that the chip will be opened just once,
 930  * by the check of is_open variable, which is protected
 931  * by driver_lock.
 932  */
 933 int tpm_open(struct inode *inode, struct file *file)
 934 {
 935         int minor = iminor(inode);
 936         struct tpm_chip *chip = NULL, *pos;
 937
 938         rcu_read_lock();
 939         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
 940                 if (pos->vendor.miscdev.minor == minor) {
 941                         chip = pos;
 942                         get_device(chip->dev);
 943                         break;
 944                 }
 945         }
 946         rcu_read_unlock();
 947
 948         if (!chip)
 949                 return -ENODEV;
 950
 951         if (test_and_set_bit(0, &chip->is_open)) {
 952                 dev_dbg(chip->dev, "Another process owns this TPM\n");
 953                 put_device(chip->dev);
 954                 return -EBUSY;
 955         }
 956
 957         chip->data_buffer = kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
 958         if (chip->data_buffer == NULL) {
 959                 clear_bit(0, &chip->is_open);
 960                 put_device(chip->dev);
 961                 return -ENOMEM;
 962         }
 963
 964         atomic_set(&chip->data_pending, 0);
 965
 966         file->private_data = chip;
 967         return 0;
 968 }
 969 EXPORT_SYMBOL_GPL(tpm_open);
 970
 971 /*
 972  * Called on file close
 973  */
 974 int tpm_release(struct inode *inode, struct file *file)
 975 {
 976         struct tpm_chip *chip = file->private_data;
 977
 978         del_singleshot_timer_sync(&chip->user_read_timer);
 979         flush_scheduled_work();
 980         file->private_data = NULL;
 981         atomic_set(&chip->data_pending, 0);
 982         kfree(chip->data_buffer);
 983         clear_bit(0, &chip->is_open);
 984         put_device(chip->dev);
 985         return 0;
 986 }
 987 EXPORT_SYMBOL_GPL(tpm_release);
 988
 989 ssize_t tpm_write(struct file *file, const char __user *buf,
 990                   size_t size, loff_t *off)
 991 {
 992         struct tpm_chip *chip = file->private_data;
 993         size_t in_size = size, out_size;
 994
 995         /* cannot perform a write until the read has cleared
 996            either via tpm_read or a user_read_timer timeout */
 997         while (atomic_read(&chip->data_pending) != 0)
 998                 msleep(TPM_TIMEOUT);
 999
1000         mutex_lock(&chip->buffer_mutex);
1001
1002         if (in_size > TPM_BUFSIZE)
1003                 in_size = TPM_BUFSIZE;
1004
1005         if (copy_from_user
1006             (chip->data_buffer, (void __user *) buf, in_size)) {
1007                 mutex_unlock(&chip->buffer_mutex);
1008                 return -EFAULT;
1009         }
1010
1011         /* atomic tpm command send and result receive */
1012         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1013
1014         atomic_set(&chip->data_pending, out_size);
1015         mutex_unlock(&chip->buffer_mutex);
1016
1017         /* Set a timeout by which the reader must come claim the result */
1018         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1019
1020         return in_size;
1021 }
1022 EXPORT_SYMBOL_GPL(tpm_write);
1023
1024 ssize_t tpm_read(struct file *file, char __user *buf,
1025                  size_t size, loff_t *off)
1026 {
1027         struct tpm_chip *chip = file->private_data;
1028         ssize_t ret_size;
1029
1030         del_singleshot_timer_sync(&chip->user_read_timer);
1031         flush_scheduled_work();
1032         ret_size = atomic_read(&chip->data_pending);
1033         atomic_set(&chip->data_pending, 0);
1034         if (ret_size > 0) {     /* relay data */
1035                 if (size < ret_size)
1036                         ret_size = size;
1037
1038                 mutex_lock(&chip->buffer_mutex);
1039                 if (copy_to_user(buf, chip->data_buffer, ret_size))
1040                         ret_size = -EFAULT;
1041                 mutex_unlock(&chip->buffer_mutex);
1042         }
1043
1044         return ret_size;
1045 }
1046 EXPORT_SYMBOL_GPL(tpm_read);
1047
1048 void tpm_remove_hardware(struct device *dev)
1049 {
1050         struct tpm_chip *chip = dev_get_drvdata(dev);
1051
1052         if (chip == NULL) {
1053                 dev_err(dev, "No device data found\n");
1054                 return;
1055         }
1056
1057         spin_lock(&driver_lock);
1058         list_del_rcu(&chip->list);
1059         spin_unlock(&driver_lock);
1060         synchronize_rcu();
1061
1062         misc_deregister(&chip->vendor.miscdev);
1063         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1064         tpm_bios_log_teardown(chip->bios_dir);
1065
1066         /* write it this way to be explicit (chip->dev == dev) */
1067         put_device(chip->dev);
1068 }
1069 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1070
1071 /*
1072  * We are about to suspend. Save the TPM state
1073  * so that it can be restored.
1074  */
1075 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1076 {
1077         struct tpm_chip *chip = dev_get_drvdata(dev);
1078         u8 savestate[] = {
1079                 0, 193,         /* TPM_TAG_RQU_COMMAND */
1080                 0, 0, 0, 10,    /* blob length (in bytes) */
1081                 0, 0, 0, 152    /* TPM_ORD_SaveState */
1082         };
1083
1084         if (chip == NULL)
1085                 return -ENODEV;
1086
1087         tpm_transmit(chip, savestate, sizeof(savestate));
1088         return 0;
1089 }
1090 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1091
1092 /*
1093  * Resume from a power safe. The BIOS already restored
1094  * the TPM state.
1095  */
1096 int tpm_pm_resume(struct device *dev)
1097 {
1098         struct tpm_chip *chip = dev_get_drvdata(dev);
1099
1100         if (chip == NULL)
1101                 return -ENODEV;
1102
1103         return 0;
1104 }
1105 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1106
1107 /* In case vendor provided release function, call it too.*/
1108
1109 void tpm_dev_vendor_release(struct tpm_chip *chip)
1110 {
1111         if (chip->vendor.release)
1112                 chip->vendor.release(chip->dev);
1113
1114         clear_bit(chip->dev_num, dev_mask);
1115         kfree(chip->vendor.miscdev.name);
1116 }
1117 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1118
1119
1120 /*
1121  * Once all references to platform device are down to 0,
1122  * release all allocated structures.
1123  */
1124 void tpm_dev_release(struct device *dev)
1125 {
1126         struct tpm_chip *chip = dev_get_drvdata(dev);
1127
1128         tpm_dev_vendor_release(chip);
1129
1130         chip->release(dev);
1131         kfree(chip);
1132 }
1133 EXPORT_SYMBOL_GPL(tpm_dev_release);
1134
1135 /*
1136  * Called from tpm_<specific>.c probe function only for devices
1137  * the driver has determined it should claim.  Prior to calling
1138  * this function the specific probe function has called pci_enable_device
1139  * upon errant exit from this function specific probe function should call
1140  * pci_disable_device
1141  */
1142 struct tpm_chip *tpm_register_hardware(struct device *dev,
1143                                         const struct tpm_vendor_specific *entry)
1144 {
1145 #define DEVNAME_SIZE 7
1146
1147         char *devname;
1148         struct tpm_chip *chip;
1149
1150         /* Driver specific per-device data */
1151         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1152         devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1153
1154         if (chip == NULL || devname == NULL)
1155                 goto out_free;
1156
1157         mutex_init(&chip->buffer_mutex);
1158         mutex_init(&chip->tpm_mutex);
1159         INIT_LIST_HEAD(&chip->list);
1160
1161         INIT_WORK(&chip->work, timeout_work);
1162
1163         setup_timer(&chip->user_read_timer, user_reader_timeout,
1164                         (unsigned long)chip);
1165
1166         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1167
1168         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1169
1170         if (chip->dev_num >= TPM_NUM_DEVICES) {
1171                 dev_err(dev, "No available tpm device numbers\n");
1172                 goto out_free;
1173         } else if (chip->dev_num == 0)
1174                 chip->vendor.miscdev.minor = TPM_MINOR;
1175         else
1176                 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1177
1178         set_bit(chip->dev_num, dev_mask);
1179
1180         scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1181         chip->vendor.miscdev.name = devname;
1182
1183         chip->vendor.miscdev.parent = dev;
1184         chip->dev = get_device(dev);
1185         chip->release = dev->release;
1186         dev->release = tpm_dev_release;
1187         dev_set_drvdata(dev, chip);
1188
1189         if (misc_register(&chip->vendor.miscdev)) {
1190                 dev_err(chip->dev,
1191                         "unable to misc_register %s, minor %d\n",
1192                         chip->vendor.miscdev.name,
1193                         chip->vendor.miscdev.minor);
1194                 put_device(chip->dev);
1195                 return NULL;
1196         }
1197
1198         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1199                 misc_deregister(&chip->vendor.miscdev);
1200                 put_device(chip->dev);
1201
1202                 return NULL;
1203         }
1204
1205         chip->bios_dir = tpm_bios_log_setup(devname);
1206
1207         /* Make chip available */
1208         spin_lock(&driver_lock);
1209         list_add_rcu(&chip->list, &tpm_chip_list);
1210         spin_unlock(&driver_lock);
1211
1212         return chip;
1213
1214 out_free:
1215         kfree(chip);
1216         kfree(devname);
1217         return NULL;
1218 }
1219 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1220
1221 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1222 MODULE_DESCRIPTION("TPM Driver");
1223 MODULE_VERSION("2.0");
1224 MODULE_LICENSE("GPL");