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/sched.h>
  27 #include <linux/poll.h>
  28 #include <linux/spinlock.h>
  29 #include "tpm.h"
  30
  31 enum tpm_const {
  32         TPM_MINOR = 224,        /* officially assigned */
  33         TPM_BUFSIZE = 2048,
  34         TPM_NUM_DEVICES = 256,
  35 };
  36
  37 enum tpm_duration {
  38         TPM_SHORT = 0,
  39         TPM_MEDIUM = 1,
  40         TPM_LONG = 2,
  41         TPM_UNDEFINED,
  42 };
  43
  44 #define TPM_MAX_ORDINAL 243
  45 #define TPM_MAX_PROTECTED_ORDINAL 12
  46 #define TPM_PROTECTED_ORDINAL_MASK 0xFF
  47
  48 static LIST_HEAD(tpm_chip_list);
  49 static DEFINE_SPINLOCK(driver_lock);
  50 static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
  51
  52 /*
  53  * Array with one entry per ordinal defining the maximum amount
  54  * of time the chip could take to return the result.  The ordinal
  55  * designation of short, medium or long is defined in a table in
  56  * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
  57  * values of the SHORT, MEDIUM, and LONG durations are retrieved
  58  * from the chip during initialization with a call to tpm_get_timeouts.
  59  */
  60 static const u8 tpm_protected_ordinal_duration[TPM_MAX_PROTECTED_ORDINAL] = {
  61         TPM_UNDEFINED,          /* 0 */
  62         TPM_UNDEFINED,
  63         TPM_UNDEFINED,
  64         TPM_UNDEFINED,
  65         TPM_UNDEFINED,
  66         TPM_UNDEFINED,          /* 5 */
  67         TPM_UNDEFINED,
  68         TPM_UNDEFINED,
  69         TPM_UNDEFINED,
  70         TPM_UNDEFINED,
  71         TPM_SHORT,              /* 10 */
  72         TPM_SHORT,
  73 };
  74
  75 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
  76         TPM_UNDEFINED,          /* 0 */
  77         TPM_UNDEFINED,
  78         TPM_UNDEFINED,
  79         TPM_UNDEFINED,
  80         TPM_UNDEFINED,
  81         TPM_UNDEFINED,          /* 5 */
  82         TPM_UNDEFINED,
  83         TPM_UNDEFINED,
  84         TPM_UNDEFINED,
  85         TPM_UNDEFINED,
  86         TPM_SHORT,              /* 10 */
  87         TPM_SHORT,
  88         TPM_MEDIUM,
  89         TPM_LONG,
  90         TPM_LONG,
  91         TPM_MEDIUM,             /* 15 */
  92         TPM_SHORT,
  93         TPM_SHORT,
  94         TPM_MEDIUM,
  95         TPM_LONG,
  96         TPM_SHORT,              /* 20 */
  97         TPM_SHORT,
  98         TPM_MEDIUM,
  99         TPM_MEDIUM,
 100         TPM_MEDIUM,
 101         TPM_SHORT,              /* 25 */
 102         TPM_SHORT,
 103         TPM_MEDIUM,
 104         TPM_SHORT,
 105         TPM_SHORT,
 106         TPM_MEDIUM,             /* 30 */
 107         TPM_LONG,
 108         TPM_MEDIUM,
 109         TPM_SHORT,
 110         TPM_SHORT,
 111         TPM_SHORT,              /* 35 */
 112         TPM_MEDIUM,
 113         TPM_MEDIUM,
 114         TPM_UNDEFINED,
 115         TPM_UNDEFINED,
 116         TPM_MEDIUM,             /* 40 */
 117         TPM_LONG,
 118         TPM_MEDIUM,
 119         TPM_SHORT,
 120         TPM_SHORT,
 121         TPM_SHORT,              /* 45 */
 122         TPM_SHORT,
 123         TPM_SHORT,
 124         TPM_SHORT,
 125         TPM_LONG,
 126         TPM_MEDIUM,             /* 50 */
 127         TPM_MEDIUM,
 128         TPM_UNDEFINED,
 129         TPM_UNDEFINED,
 130         TPM_UNDEFINED,
 131         TPM_UNDEFINED,          /* 55 */
 132         TPM_UNDEFINED,
 133         TPM_UNDEFINED,
 134         TPM_UNDEFINED,
 135         TPM_UNDEFINED,
 136         TPM_MEDIUM,             /* 60 */
 137         TPM_MEDIUM,
 138         TPM_MEDIUM,
 139         TPM_SHORT,
 140         TPM_SHORT,
 141         TPM_MEDIUM,             /* 65 */
 142         TPM_UNDEFINED,
 143         TPM_UNDEFINED,
 144         TPM_UNDEFINED,
 145         TPM_UNDEFINED,
 146         TPM_SHORT,              /* 70 */
 147         TPM_SHORT,
 148         TPM_UNDEFINED,
 149         TPM_UNDEFINED,
 150         TPM_UNDEFINED,
 151         TPM_UNDEFINED,          /* 75 */
 152         TPM_UNDEFINED,
 153         TPM_UNDEFINED,
 154         TPM_UNDEFINED,
 155         TPM_UNDEFINED,
 156         TPM_LONG,               /* 80 */
 157         TPM_UNDEFINED,
 158         TPM_MEDIUM,
 159         TPM_LONG,
 160         TPM_SHORT,
 161         TPM_UNDEFINED,          /* 85 */
 162         TPM_UNDEFINED,
 163         TPM_UNDEFINED,
 164         TPM_UNDEFINED,
 165         TPM_UNDEFINED,
 166         TPM_SHORT,              /* 90 */
 167         TPM_SHORT,
 168         TPM_SHORT,
 169         TPM_SHORT,
 170         TPM_SHORT,
 171         TPM_UNDEFINED,          /* 95 */
 172         TPM_UNDEFINED,
 173         TPM_UNDEFINED,
 174         TPM_UNDEFINED,
 175         TPM_UNDEFINED,
 176         TPM_MEDIUM,             /* 100 */
 177         TPM_SHORT,
 178         TPM_SHORT,
 179         TPM_UNDEFINED,
 180         TPM_UNDEFINED,
 181         TPM_UNDEFINED,          /* 105 */
 182         TPM_UNDEFINED,
 183         TPM_UNDEFINED,
 184         TPM_UNDEFINED,
 185         TPM_UNDEFINED,
 186         TPM_SHORT,              /* 110 */
 187         TPM_SHORT,
 188         TPM_SHORT,
 189         TPM_SHORT,
 190         TPM_SHORT,
 191         TPM_SHORT,              /* 115 */
 192         TPM_SHORT,
 193         TPM_SHORT,
 194         TPM_UNDEFINED,
 195         TPM_UNDEFINED,
 196         TPM_LONG,               /* 120 */
 197         TPM_LONG,
 198         TPM_MEDIUM,
 199         TPM_UNDEFINED,
 200         TPM_SHORT,
 201         TPM_SHORT,              /* 125 */
 202         TPM_SHORT,
 203         TPM_LONG,
 204         TPM_SHORT,
 205         TPM_SHORT,
 206         TPM_SHORT,              /* 130 */
 207         TPM_MEDIUM,
 208         TPM_UNDEFINED,
 209         TPM_SHORT,
 210         TPM_MEDIUM,
 211         TPM_UNDEFINED,          /* 135 */
 212         TPM_UNDEFINED,
 213         TPM_UNDEFINED,
 214         TPM_UNDEFINED,
 215         TPM_UNDEFINED,
 216         TPM_SHORT,              /* 140 */
 217         TPM_SHORT,
 218         TPM_UNDEFINED,
 219         TPM_UNDEFINED,
 220         TPM_UNDEFINED,
 221         TPM_UNDEFINED,          /* 145 */
 222         TPM_UNDEFINED,
 223         TPM_UNDEFINED,
 224         TPM_UNDEFINED,
 225         TPM_UNDEFINED,
 226         TPM_SHORT,              /* 150 */
 227         TPM_MEDIUM,
 228         TPM_MEDIUM,
 229         TPM_SHORT,
 230         TPM_SHORT,
 231         TPM_UNDEFINED,          /* 155 */
 232         TPM_UNDEFINED,
 233         TPM_UNDEFINED,
 234         TPM_UNDEFINED,
 235         TPM_UNDEFINED,
 236         TPM_SHORT,              /* 160 */
 237         TPM_SHORT,
 238         TPM_SHORT,
 239         TPM_SHORT,
 240         TPM_UNDEFINED,
 241         TPM_UNDEFINED,          /* 165 */
 242         TPM_UNDEFINED,
 243         TPM_UNDEFINED,
 244         TPM_UNDEFINED,
 245         TPM_UNDEFINED,
 246         TPM_LONG,               /* 170 */
 247         TPM_UNDEFINED,
 248         TPM_UNDEFINED,
 249         TPM_UNDEFINED,
 250         TPM_UNDEFINED,
 251         TPM_UNDEFINED,          /* 175 */
 252         TPM_UNDEFINED,
 253         TPM_UNDEFINED,
 254         TPM_UNDEFINED,
 255         TPM_UNDEFINED,
 256         TPM_MEDIUM,             /* 180 */
 257         TPM_SHORT,
 258         TPM_MEDIUM,
 259         TPM_MEDIUM,
 260         TPM_MEDIUM,
 261         TPM_MEDIUM,             /* 185 */
 262         TPM_SHORT,
 263         TPM_UNDEFINED,
 264         TPM_UNDEFINED,
 265         TPM_UNDEFINED,
 266         TPM_UNDEFINED,          /* 190 */
 267         TPM_UNDEFINED,
 268         TPM_UNDEFINED,
 269         TPM_UNDEFINED,
 270         TPM_UNDEFINED,
 271         TPM_UNDEFINED,          /* 195 */
 272         TPM_UNDEFINED,
 273         TPM_UNDEFINED,
 274         TPM_UNDEFINED,
 275         TPM_UNDEFINED,
 276         TPM_SHORT,              /* 200 */
 277         TPM_UNDEFINED,
 278         TPM_UNDEFINED,
 279         TPM_UNDEFINED,
 280         TPM_SHORT,
 281         TPM_SHORT,              /* 205 */
 282         TPM_SHORT,
 283         TPM_SHORT,
 284         TPM_SHORT,
 285         TPM_SHORT,
 286         TPM_MEDIUM,             /* 210 */
 287         TPM_UNDEFINED,
 288         TPM_MEDIUM,
 289         TPM_MEDIUM,
 290         TPM_MEDIUM,
 291         TPM_UNDEFINED,          /* 215 */
 292         TPM_MEDIUM,
 293         TPM_UNDEFINED,
 294         TPM_UNDEFINED,
 295         TPM_SHORT,
 296         TPM_SHORT,              /* 220 */
 297         TPM_SHORT,
 298         TPM_SHORT,
 299         TPM_SHORT,
 300         TPM_SHORT,
 301         TPM_UNDEFINED,          /* 225 */
 302         TPM_UNDEFINED,
 303         TPM_UNDEFINED,
 304         TPM_UNDEFINED,
 305         TPM_UNDEFINED,
 306         TPM_SHORT,              /* 230 */
 307         TPM_LONG,
 308         TPM_MEDIUM,
 309         TPM_UNDEFINED,
 310         TPM_UNDEFINED,
 311         TPM_UNDEFINED,          /* 235 */
 312         TPM_UNDEFINED,
 313         TPM_UNDEFINED,
 314         TPM_UNDEFINED,
 315         TPM_UNDEFINED,
 316         TPM_SHORT,              /* 240 */
 317         TPM_UNDEFINED,
 318         TPM_MEDIUM,
 319 };
 320
 321 static void user_reader_timeout(unsigned long ptr)
 322 {
 323         struct tpm_chip *chip = (struct tpm_chip *) ptr;
 324
 325         schedule_work(&chip->work);
 326 }
 327
 328 static void timeout_work(void *ptr)
 329 {
 330         struct tpm_chip *chip = ptr;
 331
 332         down(&chip->buffer_mutex);
 333         atomic_set(&chip->data_pending, 0);
 334         memset(chip->data_buffer, 0, TPM_BUFSIZE);
 335         up(&chip->buffer_mutex);
 336 }
 337
 338 /*
 339  * Returns max number of jiffies to wait
 340  */
 341 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
 342                                            u32 ordinal)
 343 {
 344         int duration_idx = TPM_UNDEFINED;
 345         int duration = 0;
 346
 347         if (ordinal < TPM_MAX_ORDINAL)
 348                 duration_idx = tpm_ordinal_duration[ordinal];
 349         else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
 350                  TPM_MAX_PROTECTED_ORDINAL)
 351                 duration_idx =
 352                     tpm_protected_ordinal_duration[ordinal &
 353                                                    TPM_PROTECTED_ORDINAL_MASK];
 354
 355         if (duration_idx != TPM_UNDEFINED)
 356                 duration = chip->vendor.duration[duration_idx];
 357         if (duration <= 0)
 358                 return 2 * 60 * HZ;
 359         else
 360                 return duration;
 361 }
 362 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 363
 364 /*
 365  * Internal kernel interface to transmit TPM commands
 366  */
 367 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
 368                             size_t bufsiz)
 369 {
 370         ssize_t rc;
 371         u32 count, ordinal;
 372         unsigned long stop;
 373
 374         count = be32_to_cpu(*((__be32 *) (buf + 2)));
 375         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
 376         if (count == 0)
 377                 return -ENODATA;
 378         if (count > bufsiz) {
 379                 dev_err(chip->dev,
 380                         "invalid count value %x %zx \n", count, bufsiz);
 381                 return -E2BIG;
 382         }
 383
 384         down(&chip->tpm_mutex);
 385
 386         if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
 387                 dev_err(chip->dev,
 388                         "tpm_transmit: tpm_send: error %zd\n", rc);
 389                 goto out;
 390         }
 391
 392         if (chip->vendor.irq)
 393                 goto out_recv;
 394
 395         stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
 396         do {
 397                 u8 status = chip->vendor.status(chip);
 398                 if ((status & chip->vendor.req_complete_mask) ==
 399                     chip->vendor.req_complete_val)
 400                         goto out_recv;
 401
 402                 if ((status == chip->vendor.req_canceled)) {
 403                         dev_err(chip->dev, "Operation Canceled\n");
 404                         rc = -ECANCELED;
 405                         goto out;
 406                 }
 407
 408                 msleep(TPM_TIMEOUT);    /* CHECK */
 409                 rmb();
 410         } while (time_before(jiffies, stop));
 411
 412         chip->vendor.cancel(chip);
 413         dev_err(chip->dev, "Operation Timed out\n");
 414         rc = -ETIME;
 415         goto out;
 416
 417 out_recv:
 418         rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
 419         if (rc < 0)
 420                 dev_err(chip->dev,
 421                         "tpm_transmit: tpm_recv: error %zd\n", rc);
 422 out:
 423         up(&chip->tpm_mutex);
 424         return rc;
 425 }
 426
 427 #define TPM_DIGEST_SIZE 20
 428 #define TPM_ERROR_SIZE 10
 429 #define TPM_RET_CODE_IDX 6
 430 #define TPM_GET_CAP_RET_SIZE_IDX 10
 431 #define TPM_GET_CAP_RET_UINT32_1_IDX 14
 432 #define TPM_GET_CAP_RET_UINT32_2_IDX 18
 433 #define TPM_GET_CAP_RET_UINT32_3_IDX 22
 434 #define TPM_GET_CAP_RET_UINT32_4_IDX 26
 435 #define TPM_GET_CAP_PERM_DISABLE_IDX 16
 436 #define TPM_GET_CAP_PERM_INACTIVE_IDX 18
 437 #define TPM_GET_CAP_RET_BOOL_1_IDX 14
 438 #define TPM_GET_CAP_TEMP_INACTIVE_IDX 16
 439
 440 #define TPM_CAP_IDX 13
 441 #define TPM_CAP_SUBCAP_IDX 21
 442
 443 enum tpm_capabilities {
 444         TPM_CAP_FLAG = 4,
 445         TPM_CAP_PROP = 5,
 446 };
 447
 448 enum tpm_sub_capabilities {
 449         TPM_CAP_PROP_PCR = 0x1,
 450         TPM_CAP_PROP_MANUFACTURER = 0x3,
 451         TPM_CAP_FLAG_PERM = 0x8,
 452         TPM_CAP_FLAG_VOL = 0x9,
 453         TPM_CAP_PROP_OWNER = 0x11,
 454         TPM_CAP_PROP_TIS_TIMEOUT = 0x15,
 455         TPM_CAP_PROP_TIS_DURATION = 0x20,
 456 };
 457
 458 /*
 459  * This is a semi generic GetCapability command for use
 460  * with the capability type TPM_CAP_PROP or TPM_CAP_FLAG
 461  * and their associated sub_capabilities.
 462  */
 463
 464 static const u8 tpm_cap[] = {
 465         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 466         0, 0, 0, 22,            /* length */
 467         0, 0, 0, 101,           /* TPM_ORD_GetCapability */
 468         0, 0, 0, 0,             /* TPM_CAP_<TYPE> */
 469         0, 0, 0, 4,             /* TPM_CAP_SUB_<TYPE> size */
 470         0, 0, 1, 0              /* TPM_CAP_SUB_<TYPE> */
 471 };
 472
 473 static ssize_t transmit_cmd(struct tpm_chip *chip, u8 *data, int len,
 474                             char *desc)
 475 {
 476         int err;
 477
 478         len = tpm_transmit(chip, data, len);
 479         if (len <  0)
 480                 return len;
 481         if (len == TPM_ERROR_SIZE) {
 482                 err = be32_to_cpu(*((__be32 *) (data + TPM_RET_CODE_IDX)));
 483                 dev_dbg(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
 484                 return err;
 485         }
 486         return 0;
 487 }
 488
 489 void tpm_gen_interrupt(struct tpm_chip *chip)
 490 {
 491         u8 data[max_t(int, ARRAY_SIZE(tpm_cap), 30)];
 492         ssize_t rc;
 493
 494         memcpy(data, tpm_cap, sizeof(tpm_cap));
 495         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 496         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_TIS_TIMEOUT;
 497
 498         rc = transmit_cmd(chip, data, sizeof(data),
 499                         "attempting to determine the timeouts");
 500 }
 501 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
 502
 503 void tpm_get_timeouts(struct tpm_chip *chip)
 504 {
 505         u8 data[max_t(int, ARRAY_SIZE(tpm_cap), 30)];
 506         ssize_t rc;
 507         u32 timeout;
 508
 509         memcpy(data, tpm_cap, sizeof(tpm_cap));
 510         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 511         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_TIS_TIMEOUT;
 512
 513         rc = transmit_cmd(chip, data, sizeof(data),
 514                         "attempting to determine the timeouts");
 515         if (rc)
 516                 goto duration;
 517
 518         if (be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_SIZE_IDX)))
 519             != 4 * sizeof(u32))
 520                 goto duration;
 521
 522         /* Don't overwrite default if value is 0 */
 523         timeout =
 524             be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_1_IDX)));
 525         if (timeout)
 526                 chip->vendor.timeout_a = msecs_to_jiffies(timeout);
 527         timeout =
 528             be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_2_IDX)));
 529         if (timeout)
 530                 chip->vendor.timeout_b = msecs_to_jiffies(timeout);
 531         timeout =
 532             be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_3_IDX)));
 533         if (timeout)
 534                 chip->vendor.timeout_c = msecs_to_jiffies(timeout);
 535         timeout =
 536             be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_4_IDX)));
 537         if (timeout)
 538                 chip->vendor.timeout_d = msecs_to_jiffies(timeout);
 539
 540 duration:
 541         memcpy(data, tpm_cap, sizeof(tpm_cap));
 542         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 543         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_TIS_DURATION;
 544
 545         rc = transmit_cmd(chip, data, sizeof(data),
 546                         "attempting to determine the durations");
 547         if (rc)
 548                 return;
 549
 550         if (be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_SIZE_IDX)))
 551             != 3 * sizeof(u32))
 552                 return;
 553
 554         chip->vendor.duration[TPM_SHORT] =
 555             msecs_to_jiffies(be32_to_cpu
 556                              (*((__be32 *) (data +
 557                                             TPM_GET_CAP_RET_UINT32_1_IDX))));
 558         chip->vendor.duration[TPM_MEDIUM] =
 559             msecs_to_jiffies(be32_to_cpu
 560                              (*((__be32 *) (data +
 561                                             TPM_GET_CAP_RET_UINT32_2_IDX))));
 562         chip->vendor.duration[TPM_LONG] =
 563             msecs_to_jiffies(be32_to_cpu
 564                              (*((__be32 *) (data +
 565                                             TPM_GET_CAP_RET_UINT32_3_IDX))));
 566 }
 567 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
 568
 569 void tpm_continue_selftest(struct tpm_chip *chip)
 570 {
 571         u8 data[] = {
 572                 0, 193,                 /* TPM_TAG_RQU_COMMAND */
 573                 0, 0, 0, 10,            /* length */
 574                 0, 0, 0, 83,            /* TPM_ORD_GetCapability */
 575         };
 576
 577         tpm_transmit(chip, data, sizeof(data));
 578 }
 579 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
 580
 581 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
 582                         char *buf)
 583 {
 584         u8 data[max_t(int, ARRAY_SIZE(tpm_cap), 35)];
 585         ssize_t rc;
 586
 587         struct tpm_chip *chip = dev_get_drvdata(dev);
 588         if (chip == NULL)
 589                 return -ENODEV;
 590
 591         memcpy(data, tpm_cap, sizeof(tpm_cap));
 592         data[TPM_CAP_IDX] = TPM_CAP_FLAG;
 593         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_FLAG_PERM;
 594
 595         rc = transmit_cmd(chip, data, sizeof(data),
 596                         "attemtping to determine the permanent state");
 597         if (rc)
 598                 return 0;
 599         return sprintf(buf, "%d\n", !data[TPM_GET_CAP_PERM_DISABLE_IDX]);
 600 }
 601 EXPORT_SYMBOL_GPL(tpm_show_enabled);
 602
 603 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
 604                         char *buf)
 605 {
 606         u8 data[max_t(int, ARRAY_SIZE(tpm_cap), 35)];
 607         ssize_t rc;
 608
 609         struct tpm_chip *chip = dev_get_drvdata(dev);
 610         if (chip == NULL)
 611                 return -ENODEV;
 612
 613         memcpy(data, tpm_cap, sizeof(tpm_cap));
 614         data[TPM_CAP_IDX] = TPM_CAP_FLAG;
 615         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_FLAG_PERM;
 616
 617         rc = transmit_cmd(chip, data, sizeof(data),
 618                         "attemtping to determine the permanent state");
 619         if (rc)
 620                 return 0;
 621         return sprintf(buf, "%d\n", !data[TPM_GET_CAP_PERM_INACTIVE_IDX]);
 622 }
 623 EXPORT_SYMBOL_GPL(tpm_show_active);
 624
 625 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
 626                         char *buf)
 627 {
 628         u8 data[sizeof(tpm_cap)];
 629         ssize_t rc;
 630
 631         struct tpm_chip *chip = dev_get_drvdata(dev);
 632         if (chip == NULL)
 633                 return -ENODEV;
 634
 635         memcpy(data, tpm_cap, sizeof(tpm_cap));
 636         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 637         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_OWNER;
 638
 639         rc = transmit_cmd(chip, data, sizeof(data),
 640                         "attempting to determine the owner state");
 641         if (rc)
 642                 return 0;
 643         return sprintf(buf, "%d\n", data[TPM_GET_CAP_RET_BOOL_1_IDX]);
 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         u8 data[sizeof(tpm_cap)];
 651         ssize_t rc;
 652
 653         struct tpm_chip *chip = dev_get_drvdata(dev);
 654         if (chip == NULL)
 655                 return -ENODEV;
 656
 657         memcpy(data, tpm_cap, sizeof(tpm_cap));
 658         data[TPM_CAP_IDX] = TPM_CAP_FLAG;
 659         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_FLAG_VOL;
 660
 661         rc = transmit_cmd(chip, data, sizeof(data),
 662                         "attempting to determine the temporary state");
 663         if (rc)
 664                 return 0;
 665         return sprintf(buf, "%d\n", data[TPM_GET_CAP_TEMP_INACTIVE_IDX]);
 666 }
 667 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
 668
 669 static const u8 pcrread[] = {
 670         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 671         0, 0, 0, 14,            /* length */
 672         0, 0, 0, 21,            /* TPM_ORD_PcrRead */
 673         0, 0, 0, 0              /* PCR index */
 674 };
 675
 676 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
 677                       char *buf)
 678 {
 679         u8 data[max_t(int, max(ARRAY_SIZE(tpm_cap), ARRAY_SIZE(pcrread)), 30)];
 680         ssize_t rc;
 681         int i, j, num_pcrs;
 682         __be32 index;
 683         char *str = buf;
 684
 685         struct tpm_chip *chip = dev_get_drvdata(dev);
 686         if (chip == NULL)
 687                 return -ENODEV;
 688
 689         memcpy(data, tpm_cap, sizeof(tpm_cap));
 690         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 691         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_PCR;
 692
 693         rc = transmit_cmd(chip, data, sizeof(data),
 694                         "attempting to determine the number of PCRS");
 695         if (rc)
 696                 return 0;
 697
 698         num_pcrs = be32_to_cpu(*((__be32 *) (data + 14)));
 699         for (i = 0; i < num_pcrs; i++) {
 700                 memcpy(data, pcrread, sizeof(pcrread));
 701                 index = cpu_to_be32(i);
 702                 memcpy(data + 10, &index, 4);
 703                 rc = transmit_cmd(chip, data, sizeof(data),
 704                                 "attempting to read a PCR");
 705                 if (rc)
 706                         goto out;
 707                 str += sprintf(str, "PCR-%02d: ", i);
 708                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
 709                         str += sprintf(str, "%02X ", *(data + 10 + j));
 710                 str += sprintf(str, "\n");
 711         }
 712 out:
 713         return str - buf;
 714 }
 715 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 716
 717 #define  READ_PUBEK_RESULT_SIZE 314
 718 static const u8 readpubek[] = {
 719         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 720         0, 0, 0, 30,            /* length */
 721         0, 0, 0, 124,           /* TPM_ORD_ReadPubek */
 722 };
 723
 724 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
 725                        char *buf)
 726 {
 727         u8 *data;
 728         ssize_t err;
 729         int i, rc;
 730         char *str = buf;
 731
 732         struct tpm_chip *chip = dev_get_drvdata(dev);
 733         if (chip == NULL)
 734                 return -ENODEV;
 735
 736         data = kzalloc(READ_PUBEK_RESULT_SIZE, GFP_KERNEL);
 737         if (!data)
 738                 return -ENOMEM;
 739
 740         memcpy(data, readpubek, sizeof(readpubek));
 741
 742         err = transmit_cmd(chip, data, READ_PUBEK_RESULT_SIZE,
 743                         "attempting to read the PUBEK");
 744         if (err)
 745                 goto out;
 746
 747         /*
 748            ignore header 10 bytes
 749            algorithm 32 bits (1 == RSA )
 750            encscheme 16 bits
 751            sigscheme 16 bits
 752            parameters (RSA 12->bytes: keybit, #primes, expbit)
 753            keylenbytes 32 bits
 754            256 byte modulus
 755            ignore checksum 20 bytes
 756          */
 757
 758         str +=
 759             sprintf(str,
 760                     "Algorithm: %02X %02X %02X %02X\nEncscheme: %02X %02X\n"
 761                     "Sigscheme: %02X %02X\nParameters: %02X %02X %02X %02X"
 762                     " %02X %02X %02X %02X %02X %02X %02X %02X\n"
 763                     "Modulus length: %d\nModulus: \n",
 764                     data[10], data[11], data[12], data[13], data[14],
 765                     data[15], data[16], data[17], data[22], data[23],
 766                     data[24], data[25], data[26], data[27], data[28],
 767                     data[29], data[30], data[31], data[32], data[33],
 768                     be32_to_cpu(*((__be32 *) (data + 34))));
 769
 770         for (i = 0; i < 256; i++) {
 771                 str += sprintf(str, "%02X ", data[i + 38]);
 772                 if ((i + 1) % 16 == 0)
 773                         str += sprintf(str, "\n");
 774         }
 775 out:
 776         rc = str - buf;
 777         kfree(data);
 778         return rc;
 779 }
 780 EXPORT_SYMBOL_GPL(tpm_show_pubek);
 781
 782 #define CAP_VERSION_1_1 6
 783 #define CAP_VERSION_1_2 0x1A
 784 #define CAP_VERSION_IDX 13
 785 static const u8 cap_version[] = {
 786         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 787         0, 0, 0, 18,            /* length */
 788         0, 0, 0, 101,           /* TPM_ORD_GetCapability */
 789         0, 0, 0, 0,
 790         0, 0, 0, 0
 791 };
 792
 793 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
 794                       char *buf)
 795 {
 796         u8 data[max_t(int, max(ARRAY_SIZE(tpm_cap), ARRAY_SIZE(cap_version)), 30)];
 797         ssize_t rc;
 798         char *str = buf;
 799
 800         struct tpm_chip *chip = dev_get_drvdata(dev);
 801         if (chip == NULL)
 802                 return -ENODEV;
 803
 804         memcpy(data, tpm_cap, sizeof(tpm_cap));
 805         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 806         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_MANUFACTURER;
 807
 808         rc = transmit_cmd(chip, data, sizeof(data),
 809                         "attempting to determine the manufacturer");
 810         if (rc)
 811                 return 0;
 812
 813         str += sprintf(str, "Manufacturer: 0x%x\n",
 814                        be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_1_IDX))));
 815
 816         memcpy(data, cap_version, sizeof(cap_version));
 817         data[CAP_VERSION_IDX] = CAP_VERSION_1_1;
 818         rc = transmit_cmd(chip, data, sizeof(data),
 819                         "attempting to determine the 1.1 version");
 820         if (rc)
 821                 goto out;
 822
 823         str += sprintf(str,
 824                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
 825                        (int) data[14], (int) data[15], (int) data[16],
 826                        (int) data[17]);
 827
 828 out:
 829         return str - buf;
 830 }
 831 EXPORT_SYMBOL_GPL(tpm_show_caps);
 832
 833 ssize_t tpm_show_caps_1_2(struct device * dev,
 834                           struct device_attribute * attr, char *buf)
 835 {
 836         u8 data[max_t(int, max(ARRAY_SIZE(tpm_cap), ARRAY_SIZE(cap_version)), 30)];
 837         ssize_t len;
 838         char *str = buf;
 839
 840         struct tpm_chip *chip = dev_get_drvdata(dev);
 841         if (chip == NULL)
 842                 return -ENODEV;
 843
 844         memcpy(data, tpm_cap, sizeof(tpm_cap));
 845         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 846         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_MANUFACTURER;
 847
 848         if ((len = tpm_transmit(chip, data, sizeof(data))) <=
 849             TPM_ERROR_SIZE) {
 850                 dev_dbg(chip->dev, "A TPM error (%d) occurred "
 851                         "attempting to determine the manufacturer\n",
 852                         be32_to_cpu(*((__be32 *) (data + TPM_RET_CODE_IDX))));
 853                 return 0;
 854         }
 855
 856         str += sprintf(str, "Manufacturer: 0x%x\n",
 857                        be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_1_IDX))));
 858
 859         memcpy(data, cap_version, sizeof(cap_version));
 860         data[CAP_VERSION_IDX] = CAP_VERSION_1_2;
 861
 862         if ((len = tpm_transmit(chip, data, sizeof(data))) <=
 863             TPM_ERROR_SIZE) {
 864                 dev_err(chip->dev, "A TPM error (%d) occurred "
 865                         "attempting to determine the 1.2 version\n",
 866                         be32_to_cpu(*((__be32 *) (data + TPM_RET_CODE_IDX))));
 867                 goto out;
 868         }
 869         str += sprintf(str,
 870                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
 871                        (int) data[16], (int) data[17], (int) data[18],
 872                        (int) data[19]);
 873
 874 out:
 875         return str - buf;
 876 }
 877 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
 878
 879 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
 880                         const char *buf, size_t count)
 881 {
 882         struct tpm_chip *chip = dev_get_drvdata(dev);
 883         if (chip == NULL)
 884                 return 0;
 885
 886         chip->vendor.cancel(chip);
 887         return count;
 888 }
 889 EXPORT_SYMBOL_GPL(tpm_store_cancel);
 890
 891 /*
 892  * Device file system interface to the TPM
 893  */
 894 int tpm_open(struct inode *inode, struct file *file)
 895 {
 896         int rc = 0, minor = iminor(inode);
 897         struct tpm_chip *chip = NULL, *pos;
 898
 899         spin_lock(&driver_lock);
 900
 901         list_for_each_entry(pos, &tpm_chip_list, list) {
 902                 if (pos->vendor.miscdev.minor == minor) {
 903                         chip = pos;
 904                         break;
 905                 }
 906         }
 907
 908         if (chip == NULL) {
 909                 rc = -ENODEV;
 910                 goto err_out;
 911         }
 912
 913         if (chip->num_opens) {
 914                 dev_dbg(chip->dev, "Another process owns this TPM\n");
 915                 rc = -EBUSY;
 916                 goto err_out;
 917         }
 918
 919         chip->num_opens++;
 920         get_device(chip->dev);
 921
 922         spin_unlock(&driver_lock);
 923
 924         chip->data_buffer = kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
 925         if (chip->data_buffer == NULL) {
 926                 chip->num_opens--;
 927                 put_device(chip->dev);
 928                 return -ENOMEM;
 929         }
 930
 931         atomic_set(&chip->data_pending, 0);
 932
 933         file->private_data = chip;
 934         return 0;
 935
 936 err_out:
 937         spin_unlock(&driver_lock);
 938         return rc;
 939 }
 940 EXPORT_SYMBOL_GPL(tpm_open);
 941
 942 int tpm_release(struct inode *inode, struct file *file)
 943 {
 944         struct tpm_chip *chip = file->private_data;
 945
 946         spin_lock(&driver_lock);
 947         file->private_data = NULL;
 948         chip->num_opens--;
 949         del_singleshot_timer_sync(&chip->user_read_timer);
 950         flush_scheduled_work();
 951         atomic_set(&chip->data_pending, 0);
 952         put_device(chip->dev);
 953         kfree(chip->data_buffer);
 954         spin_unlock(&driver_lock);
 955         return 0;
 956 }
 957 EXPORT_SYMBOL_GPL(tpm_release);
 958
 959 ssize_t tpm_write(struct file *file, const char __user *buf,
 960                   size_t size, loff_t *off)
 961 {
 962         struct tpm_chip *chip = file->private_data;
 963         int in_size = size, out_size;
 964
 965         /* cannot perform a write until the read has cleared
 966            either via tpm_read or a user_read_timer timeout */
 967         while (atomic_read(&chip->data_pending) != 0)
 968                 msleep(TPM_TIMEOUT);
 969
 970         down(&chip->buffer_mutex);
 971
 972         if (in_size > TPM_BUFSIZE)
 973                 in_size = TPM_BUFSIZE;
 974
 975         if (copy_from_user
 976             (chip->data_buffer, (void __user *) buf, in_size)) {
 977                 up(&chip->buffer_mutex);
 978                 return -EFAULT;
 979         }
 980
 981         /* atomic tpm command send and result receive */
 982         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
 983
 984         atomic_set(&chip->data_pending, out_size);
 985         up(&chip->buffer_mutex);
 986
 987         /* Set a timeout by which the reader must come claim the result */
 988         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
 989
 990         return in_size;
 991 }
 992 EXPORT_SYMBOL_GPL(tpm_write);
 993
 994 ssize_t tpm_read(struct file *file, char __user *buf,
 995                  size_t size, loff_t *off)
 996 {
 997         struct tpm_chip *chip = file->private_data;
 998         int ret_size;
 999
1000         del_singleshot_timer_sync(&chip->user_read_timer);
1001         flush_scheduled_work();
1002         ret_size = atomic_read(&chip->data_pending);
1003         atomic_set(&chip->data_pending, 0);
1004         if (ret_size > 0) {     /* relay data */
1005                 if (size < ret_size)
1006                         ret_size = size;
1007
1008                 down(&chip->buffer_mutex);
1009                 if (copy_to_user(buf, chip->data_buffer, ret_size))
1010                         ret_size = -EFAULT;
1011                 up(&chip->buffer_mutex);
1012         }
1013
1014         return ret_size;
1015 }
1016 EXPORT_SYMBOL_GPL(tpm_read);
1017
1018 void tpm_remove_hardware(struct device *dev)
1019 {
1020         struct tpm_chip *chip = dev_get_drvdata(dev);
1021
1022         if (chip == NULL) {
1023                 dev_err(dev, "No device data found\n");
1024                 return;
1025         }
1026
1027         spin_lock(&driver_lock);
1028
1029         list_del(&chip->list);
1030
1031         spin_unlock(&driver_lock);
1032
1033         dev_set_drvdata(dev, NULL);
1034         misc_deregister(&chip->vendor.miscdev);
1035         kfree(chip->vendor.miscdev.name);
1036
1037         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1038         tpm_bios_log_teardown(chip->bios_dir);
1039
1040         clear_bit(chip->dev_num, dev_mask);
1041
1042         kfree(chip);
1043
1044         put_device(dev);
1045 }
1046 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1047
1048 static u8 savestate[] = {
1049         0, 193,                 /* TPM_TAG_RQU_COMMAND */
1050         0, 0, 0, 10,            /* blob length (in bytes) */
1051         0, 0, 0, 152            /* TPM_ORD_SaveState */
1052 };
1053
1054 /*
1055  * We are about to suspend. Save the TPM state
1056  * so that it can be restored.
1057  */
1058 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1059 {
1060         struct tpm_chip *chip = dev_get_drvdata(dev);
1061         if (chip == NULL)
1062                 return -ENODEV;
1063
1064         tpm_transmit(chip, savestate, sizeof(savestate));
1065         return 0;
1066 }
1067 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1068
1069 /*
1070  * Resume from a power safe. The BIOS already restored
1071  * the TPM state.
1072  */
1073 int tpm_pm_resume(struct device *dev)
1074 {
1075         struct tpm_chip *chip = dev_get_drvdata(dev);
1076
1077         if (chip == NULL)
1078                 return -ENODEV;
1079
1080         return 0;
1081 }
1082 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1083
1084 /*
1085  * Called from tpm_<specific>.c probe function only for devices
1086  * the driver has determined it should claim.  Prior to calling
1087  * this function the specific probe function has called pci_enable_device
1088  * upon errant exit from this function specific probe function should call
1089  * pci_disable_device
1090  */
1091 struct tpm_chip *tpm_register_hardware(struct device *dev, const struct tpm_vendor_specific
1092                                        *entry)
1093 {
1094 #define DEVNAME_SIZE 7
1095
1096         char *devname;
1097         struct tpm_chip *chip;
1098
1099         /* Driver specific per-device data */
1100         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1101         if (chip == NULL)
1102                 return NULL;
1103
1104         init_MUTEX(&chip->buffer_mutex);
1105         init_MUTEX(&chip->tpm_mutex);
1106         INIT_LIST_HEAD(&chip->list);
1107
1108         INIT_WORK(&chip->work, timeout_work, chip);
1109
1110         init_timer(&chip->user_read_timer);
1111         chip->user_read_timer.function = user_reader_timeout;
1112         chip->user_read_timer.data = (unsigned long) chip;
1113
1114         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1115
1116         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1117
1118         if (chip->dev_num >= TPM_NUM_DEVICES) {
1119                 dev_err(dev, "No available tpm device numbers\n");
1120                 kfree(chip);
1121                 return NULL;
1122         } else if (chip->dev_num == 0)
1123                 chip->vendor.miscdev.minor = TPM_MINOR;
1124         else
1125                 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1126
1127         set_bit(chip->dev_num, dev_mask);
1128
1129         devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1130         scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1131         chip->vendor.miscdev.name = devname;
1132
1133         chip->vendor.miscdev.dev = dev;
1134         chip->dev = get_device(dev);
1135
1136         if (misc_register(&chip->vendor.miscdev)) {
1137                 dev_err(chip->dev,
1138                         "unable to misc_register %s, minor %d\n",
1139                         chip->vendor.miscdev.name,
1140                         chip->vendor.miscdev.minor);
1141                 put_device(dev);
1142                 clear_bit(chip->dev_num, dev_mask);
1143                 kfree(chip);
1144                 kfree(devname);
1145                 return NULL;
1146         }
1147
1148         spin_lock(&driver_lock);
1149
1150         dev_set_drvdata(dev, chip);
1151
1152         list_add(&chip->list, &tpm_chip_list);
1153
1154         spin_unlock(&driver_lock);
1155
1156         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1157                 list_del(&chip->list);
1158                 put_device(dev);
1159                 clear_bit(chip->dev_num, dev_mask);
1160                 kfree(chip);
1161                 kfree(devname);
1162                 return NULL;
1163         }
1164
1165         chip->bios_dir = tpm_bios_log_setup(devname);
1166
1167         return chip;
1168 }
1169 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1170
1171 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1172 MODULE_DESCRIPTION("TPM Driver");
1173 MODULE_VERSION("2.0");
1174 MODULE_LICENSE("GPL");