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 #define TPM_GET_CAP_RET_SIZE_IDX 10
 432 #define TPM_GET_CAP_RET_UINT32_1_IDX 14
 433 #define TPM_GET_CAP_RET_UINT32_2_IDX 18
 434 #define TPM_GET_CAP_RET_UINT32_3_IDX 22
 435 #define TPM_GET_CAP_RET_UINT32_4_IDX 26
 436 #define TPM_GET_CAP_PERM_DISABLE_IDX 16
 437 #define TPM_GET_CAP_PERM_INACTIVE_IDX 18
 438 #define TPM_GET_CAP_RET_BOOL_1_IDX 14
 439 #define TPM_GET_CAP_TEMP_INACTIVE_IDX 16
 440
 441 #define TPM_CAP_IDX 13
 442 #define TPM_CAP_SUBCAP_IDX 21
 443
 444 enum tpm_capabilities {
 445         TPM_CAP_FLAG = 4,
 446         TPM_CAP_PROP = 5,
 447 };
 448
 449 enum tpm_sub_capabilities {
 450         TPM_CAP_PROP_PCR = 0x1,
 451         TPM_CAP_PROP_MANUFACTURER = 0x3,
 452         TPM_CAP_FLAG_PERM = 0x8,
 453         TPM_CAP_FLAG_VOL = 0x9,
 454         TPM_CAP_PROP_OWNER = 0x11,
 455         TPM_CAP_PROP_TIS_TIMEOUT = 0x15,
 456         TPM_CAP_PROP_TIS_DURATION = 0x20,
 457 };
 458
 459 /*
 460  * This is a semi generic GetCapability command for use
 461  * with the capability type TPM_CAP_PROP or TPM_CAP_FLAG
 462  * and their associated sub_capabilities.
 463  */
 464
 465 static const u8 tpm_cap[] = {
 466         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 467         0, 0, 0, 22,            /* length */
 468         0, 0, 0, 101,           /* TPM_ORD_GetCapability */
 469         0, 0, 0, 0,             /* TPM_CAP_<TYPE> */
 470         0, 0, 0, 4,             /* TPM_CAP_SUB_<TYPE> size */
 471         0, 0, 1, 0              /* TPM_CAP_SUB_<TYPE> */
 472 };
 473
 474 static ssize_t transmit_cmd(struct tpm_chip *chip, u8 *data, int len,
 475                             char *desc)
 476 {
 477         int err;
 478
 479         len = tpm_transmit(chip, data, len);
 480         if (len <  0)
 481                 return len;
 482         if (len == TPM_ERROR_SIZE) {
 483                 err = be32_to_cpu(*((__be32 *) (data + TPM_RET_CODE_IDX)));
 484                 dev_dbg(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
 485                 return err;
 486         }
 487         return 0;
 488 }
 489
 490 void tpm_gen_interrupt(struct tpm_chip *chip)
 491 {
 492         u8 data[max_t(int, ARRAY_SIZE(tpm_cap), 30)];
 493         ssize_t rc;
 494
 495         memcpy(data, tpm_cap, sizeof(tpm_cap));
 496         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 497         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_TIS_TIMEOUT;
 498
 499         rc = transmit_cmd(chip, data, sizeof(data),
 500                         "attempting to determine the timeouts");
 501 }
 502 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
 503
 504 void tpm_get_timeouts(struct tpm_chip *chip)
 505 {
 506         u8 data[max_t(int, ARRAY_SIZE(tpm_cap), 30)];
 507         ssize_t rc;
 508         u32 timeout;
 509
 510         memcpy(data, tpm_cap, sizeof(tpm_cap));
 511         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 512         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_TIS_TIMEOUT;
 513
 514         rc = transmit_cmd(chip, data, sizeof(data),
 515                         "attempting to determine the timeouts");
 516         if (rc)
 517                 goto duration;
 518
 519         if (be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_SIZE_IDX)))
 520             != 4 * sizeof(u32))
 521                 goto duration;
 522
 523         /* Don't overwrite default if value is 0 */
 524         timeout =
 525             be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_1_IDX)));
 526         if (timeout)
 527                 chip->vendor.timeout_a = msecs_to_jiffies(timeout);
 528         timeout =
 529             be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_2_IDX)));
 530         if (timeout)
 531                 chip->vendor.timeout_b = msecs_to_jiffies(timeout);
 532         timeout =
 533             be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_3_IDX)));
 534         if (timeout)
 535                 chip->vendor.timeout_c = msecs_to_jiffies(timeout);
 536         timeout =
 537             be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_4_IDX)));
 538         if (timeout)
 539                 chip->vendor.timeout_d = msecs_to_jiffies(timeout);
 540
 541 duration:
 542         memcpy(data, tpm_cap, sizeof(tpm_cap));
 543         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 544         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_TIS_DURATION;
 545
 546         rc = transmit_cmd(chip, data, sizeof(data),
 547                         "attempting to determine the durations");
 548         if (rc)
 549                 return;
 550
 551         if (be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_SIZE_IDX)))
 552             != 3 * sizeof(u32))
 553                 return;
 554
 555         chip->vendor.duration[TPM_SHORT] =
 556             msecs_to_jiffies(be32_to_cpu
 557                              (*((__be32 *) (data +
 558                                             TPM_GET_CAP_RET_UINT32_1_IDX))));
 559         chip->vendor.duration[TPM_MEDIUM] =
 560             msecs_to_jiffies(be32_to_cpu
 561                              (*((__be32 *) (data +
 562                                             TPM_GET_CAP_RET_UINT32_2_IDX))));
 563         chip->vendor.duration[TPM_LONG] =
 564             msecs_to_jiffies(be32_to_cpu
 565                              (*((__be32 *) (data +
 566                                             TPM_GET_CAP_RET_UINT32_3_IDX))));
 567 }
 568 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
 569
 570 void tpm_continue_selftest(struct tpm_chip *chip)
 571 {
 572         u8 data[] = {
 573                 0, 193,                 /* TPM_TAG_RQU_COMMAND */
 574                 0, 0, 0, 10,            /* length */
 575                 0, 0, 0, 83,            /* TPM_ORD_GetCapability */
 576         };
 577
 578         tpm_transmit(chip, data, sizeof(data));
 579 }
 580 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
 581
 582 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
 583                         char *buf)
 584 {
 585         u8 data[max_t(int, ARRAY_SIZE(tpm_cap), 35)];
 586         ssize_t rc;
 587
 588         struct tpm_chip *chip = dev_get_drvdata(dev);
 589         if (chip == NULL)
 590                 return -ENODEV;
 591
 592         memcpy(data, tpm_cap, sizeof(tpm_cap));
 593         data[TPM_CAP_IDX] = TPM_CAP_FLAG;
 594         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_FLAG_PERM;
 595
 596         rc = transmit_cmd(chip, data, sizeof(data),
 597                         "attemtping to determine the permanent state");
 598         if (rc)
 599                 return 0;
 600         return sprintf(buf, "%d\n", !data[TPM_GET_CAP_PERM_DISABLE_IDX]);
 601 }
 602 EXPORT_SYMBOL_GPL(tpm_show_enabled);
 603
 604 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
 605                         char *buf)
 606 {
 607         u8 data[max_t(int, ARRAY_SIZE(tpm_cap), 35)];
 608         ssize_t rc;
 609
 610         struct tpm_chip *chip = dev_get_drvdata(dev);
 611         if (chip == NULL)
 612                 return -ENODEV;
 613
 614         memcpy(data, tpm_cap, sizeof(tpm_cap));
 615         data[TPM_CAP_IDX] = TPM_CAP_FLAG;
 616         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_FLAG_PERM;
 617
 618         rc = transmit_cmd(chip, data, sizeof(data),
 619                         "attemtping to determine the permanent state");
 620         if (rc)
 621                 return 0;
 622         return sprintf(buf, "%d\n", !data[TPM_GET_CAP_PERM_INACTIVE_IDX]);
 623 }
 624 EXPORT_SYMBOL_GPL(tpm_show_active);
 625
 626 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
 627                         char *buf)
 628 {
 629         u8 data[sizeof(tpm_cap)];
 630         ssize_t rc;
 631
 632         struct tpm_chip *chip = dev_get_drvdata(dev);
 633         if (chip == NULL)
 634                 return -ENODEV;
 635
 636         memcpy(data, tpm_cap, sizeof(tpm_cap));
 637         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 638         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_OWNER;
 639
 640         rc = transmit_cmd(chip, data, sizeof(data),
 641                         "attempting to determine the owner state");
 642         if (rc)
 643                 return 0;
 644         return sprintf(buf, "%d\n", data[TPM_GET_CAP_RET_BOOL_1_IDX]);
 645 }
 646 EXPORT_SYMBOL_GPL(tpm_show_owned);
 647
 648 ssize_t tpm_show_temp_deactivated(struct device * dev,
 649                                 struct device_attribute * attr, char *buf)
 650 {
 651         u8 data[sizeof(tpm_cap)];
 652         ssize_t rc;
 653
 654         struct tpm_chip *chip = dev_get_drvdata(dev);
 655         if (chip == NULL)
 656                 return -ENODEV;
 657
 658         memcpy(data, tpm_cap, sizeof(tpm_cap));
 659         data[TPM_CAP_IDX] = TPM_CAP_FLAG;
 660         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_FLAG_VOL;
 661
 662         rc = transmit_cmd(chip, data, sizeof(data),
 663                         "attempting to determine the temporary state");
 664         if (rc)
 665                 return 0;
 666         return sprintf(buf, "%d\n", data[TPM_GET_CAP_TEMP_INACTIVE_IDX]);
 667 }
 668 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
 669
 670 static const u8 pcrread[] = {
 671         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 672         0, 0, 0, 14,            /* length */
 673         0, 0, 0, 21,            /* TPM_ORD_PcrRead */
 674         0, 0, 0, 0              /* PCR index */
 675 };
 676
 677 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
 678                       char *buf)
 679 {
 680         u8 data[max_t(int, max(ARRAY_SIZE(tpm_cap), ARRAY_SIZE(pcrread)), 30)];
 681         ssize_t rc;
 682         int i, j, num_pcrs;
 683         __be32 index;
 684         char *str = buf;
 685
 686         struct tpm_chip *chip = dev_get_drvdata(dev);
 687         if (chip == NULL)
 688                 return -ENODEV;
 689
 690         memcpy(data, tpm_cap, sizeof(tpm_cap));
 691         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 692         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_PCR;
 693
 694         rc = transmit_cmd(chip, data, sizeof(data),
 695                         "attempting to determine the number of PCRS");
 696         if (rc)
 697                 return 0;
 698
 699         num_pcrs = be32_to_cpu(*((__be32 *) (data + 14)));
 700         for (i = 0; i < num_pcrs; i++) {
 701                 memcpy(data, pcrread, sizeof(pcrread));
 702                 index = cpu_to_be32(i);
 703                 memcpy(data + 10, &index, 4);
 704                 rc = transmit_cmd(chip, data, sizeof(data),
 705                                 "attempting to read a PCR");
 706                 if (rc)
 707                         goto out;
 708                 str += sprintf(str, "PCR-%02d: ", i);
 709                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
 710                         str += sprintf(str, "%02X ", *(data + 10 + j));
 711                 str += sprintf(str, "\n");
 712         }
 713 out:
 714         return str - buf;
 715 }
 716 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 717
 718 #define  READ_PUBEK_RESULT_SIZE 314
 719 static const u8 readpubek[] = {
 720         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 721         0, 0, 0, 30,            /* length */
 722         0, 0, 0, 124,           /* TPM_ORD_ReadPubek */
 723 };
 724
 725 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
 726                        char *buf)
 727 {
 728         u8 *data;
 729         ssize_t err;
 730         int i, rc;
 731         char *str = buf;
 732
 733         struct tpm_chip *chip = dev_get_drvdata(dev);
 734         if (chip == NULL)
 735                 return -ENODEV;
 736
 737         data = kzalloc(READ_PUBEK_RESULT_SIZE, GFP_KERNEL);
 738         if (!data)
 739                 return -ENOMEM;
 740
 741         memcpy(data, readpubek, sizeof(readpubek));
 742
 743         err = transmit_cmd(chip, data, READ_PUBEK_RESULT_SIZE,
 744                         "attempting to read the PUBEK");
 745         if (err)
 746                 goto out;
 747
 748         /*
 749            ignore header 10 bytes
 750            algorithm 32 bits (1 == RSA )
 751            encscheme 16 bits
 752            sigscheme 16 bits
 753            parameters (RSA 12->bytes: keybit, #primes, expbit)
 754            keylenbytes 32 bits
 755            256 byte modulus
 756            ignore checksum 20 bytes
 757          */
 758
 759         str +=
 760             sprintf(str,
 761                     "Algorithm: %02X %02X %02X %02X\nEncscheme: %02X %02X\n"
 762                     "Sigscheme: %02X %02X\nParameters: %02X %02X %02X %02X"
 763                     " %02X %02X %02X %02X %02X %02X %02X %02X\n"
 764                     "Modulus length: %d\nModulus: \n",
 765                     data[10], data[11], data[12], data[13], data[14],
 766                     data[15], data[16], data[17], data[22], data[23],
 767                     data[24], data[25], data[26], data[27], data[28],
 768                     data[29], data[30], data[31], data[32], data[33],
 769                     be32_to_cpu(*((__be32 *) (data + 34))));
 770
 771         for (i = 0; i < 256; i++) {
 772                 str += sprintf(str, "%02X ", data[i + 38]);
 773                 if ((i + 1) % 16 == 0)
 774                         str += sprintf(str, "\n");
 775         }
 776 out:
 777         rc = str - buf;
 778         kfree(data);
 779         return rc;
 780 }
 781 EXPORT_SYMBOL_GPL(tpm_show_pubek);
 782
 783 #define CAP_VERSION_1_1 6
 784 #define CAP_VERSION_1_2 0x1A
 785 #define CAP_VERSION_IDX 13
 786 static const u8 cap_version[] = {
 787         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 788         0, 0, 0, 18,            /* length */
 789         0, 0, 0, 101,           /* TPM_ORD_GetCapability */
 790         0, 0, 0, 0,
 791         0, 0, 0, 0
 792 };
 793
 794 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
 795                       char *buf)
 796 {
 797         u8 data[max_t(int, max(ARRAY_SIZE(tpm_cap), ARRAY_SIZE(cap_version)), 30)];
 798         ssize_t rc;
 799         char *str = buf;
 800
 801         struct tpm_chip *chip = dev_get_drvdata(dev);
 802         if (chip == NULL)
 803                 return -ENODEV;
 804
 805         memcpy(data, tpm_cap, sizeof(tpm_cap));
 806         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 807         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_MANUFACTURER;
 808
 809         rc = transmit_cmd(chip, data, sizeof(data),
 810                         "attempting to determine the manufacturer");
 811         if (rc)
 812                 return 0;
 813
 814         str += sprintf(str, "Manufacturer: 0x%x\n",
 815                        be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_1_IDX))));
 816
 817         memcpy(data, cap_version, sizeof(cap_version));
 818         data[CAP_VERSION_IDX] = CAP_VERSION_1_1;
 819         rc = transmit_cmd(chip, data, sizeof(data),
 820                         "attempting to determine the 1.1 version");
 821         if (rc)
 822                 goto out;
 823
 824         str += sprintf(str,
 825                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
 826                        (int) data[14], (int) data[15], (int) data[16],
 827                        (int) data[17]);
 828
 829 out:
 830         return str - buf;
 831 }
 832 EXPORT_SYMBOL_GPL(tpm_show_caps);
 833
 834 ssize_t tpm_show_caps_1_2(struct device * dev,
 835                           struct device_attribute * attr, char *buf)
 836 {
 837         u8 data[max_t(int, max(ARRAY_SIZE(tpm_cap), ARRAY_SIZE(cap_version)), 30)];
 838         ssize_t len;
 839         char *str = buf;
 840
 841         struct tpm_chip *chip = dev_get_drvdata(dev);
 842         if (chip == NULL)
 843                 return -ENODEV;
 844
 845         memcpy(data, tpm_cap, sizeof(tpm_cap));
 846         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 847         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_MANUFACTURER;
 848
 849         if ((len = tpm_transmit(chip, data, sizeof(data))) <=
 850             TPM_ERROR_SIZE) {
 851                 dev_dbg(chip->dev, "A TPM error (%d) occurred "
 852                         "attempting to determine the manufacturer\n",
 853                         be32_to_cpu(*((__be32 *) (data + TPM_RET_CODE_IDX))));
 854                 return 0;
 855         }
 856
 857         str += sprintf(str, "Manufacturer: 0x%x\n",
 858                        be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_1_IDX))));
 859
 860         memcpy(data, cap_version, sizeof(cap_version));
 861         data[CAP_VERSION_IDX] = CAP_VERSION_1_2;
 862
 863         if ((len = tpm_transmit(chip, data, sizeof(data))) <=
 864             TPM_ERROR_SIZE) {
 865                 dev_err(chip->dev, "A TPM error (%d) occurred "
 866                         "attempting to determine the 1.2 version\n",
 867                         be32_to_cpu(*((__be32 *) (data + TPM_RET_CODE_IDX))));
 868                 goto out;
 869         }
 870         str += sprintf(str,
 871                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
 872                        (int) data[16], (int) data[17], (int) data[18],
 873                        (int) data[19]);
 874
 875 out:
 876         return str - buf;
 877 }
 878 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
 879
 880 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
 881                         const char *buf, size_t count)
 882 {
 883         struct tpm_chip *chip = dev_get_drvdata(dev);
 884         if (chip == NULL)
 885                 return 0;
 886
 887         chip->vendor.cancel(chip);
 888         return count;
 889 }
 890 EXPORT_SYMBOL_GPL(tpm_store_cancel);
 891
 892 /*
 893  * Device file system interface to the TPM
 894  */
 895 int tpm_open(struct inode *inode, struct file *file)
 896 {
 897         int rc = 0, minor = iminor(inode);
 898         struct tpm_chip *chip = NULL, *pos;
 899
 900         spin_lock(&driver_lock);
 901
 902         list_for_each_entry(pos, &tpm_chip_list, list) {
 903                 if (pos->vendor.miscdev.minor == minor) {
 904                         chip = pos;
 905                         break;
 906                 }
 907         }
 908
 909         if (chip == NULL) {
 910                 rc = -ENODEV;
 911                 goto err_out;
 912         }
 913
 914         if (chip->num_opens) {
 915                 dev_dbg(chip->dev, "Another process owns this TPM\n");
 916                 rc = -EBUSY;
 917                 goto err_out;
 918         }
 919
 920         chip->num_opens++;
 921         get_device(chip->dev);
 922
 923         spin_unlock(&driver_lock);
 924
 925         chip->data_buffer = kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
 926         if (chip->data_buffer == NULL) {
 927                 chip->num_opens--;
 928                 put_device(chip->dev);
 929                 return -ENOMEM;
 930         }
 931
 932         atomic_set(&chip->data_pending, 0);
 933
 934         file->private_data = chip;
 935         return 0;
 936
 937 err_out:
 938         spin_unlock(&driver_lock);
 939         return rc;
 940 }
 941 EXPORT_SYMBOL_GPL(tpm_open);
 942
 943 int tpm_release(struct inode *inode, struct file *file)
 944 {
 945         struct tpm_chip *chip = file->private_data;
 946
 947         flush_scheduled_work();
 948         spin_lock(&driver_lock);
 949         file->private_data = NULL;
 950         del_singleshot_timer_sync(&chip->user_read_timer);
 951         atomic_set(&chip->data_pending, 0);
 952         chip->num_opens--;
 953         put_device(chip->dev);
 954         kfree(chip->data_buffer);
 955         spin_unlock(&driver_lock);
 956         return 0;
 957 }
 958 EXPORT_SYMBOL_GPL(tpm_release);
 959
 960 ssize_t tpm_write(struct file *file, const char __user *buf,
 961                   size_t size, loff_t *off)
 962 {
 963         struct tpm_chip *chip = file->private_data;
 964         int in_size = size, out_size;
 965
 966         /* cannot perform a write until the read has cleared
 967            either via tpm_read or a user_read_timer timeout */
 968         while (atomic_read(&chip->data_pending) != 0)
 969                 msleep(TPM_TIMEOUT);
 970
 971         mutex_lock(&chip->buffer_mutex);
 972
 973         if (in_size > TPM_BUFSIZE)
 974                 in_size = TPM_BUFSIZE;
 975
 976         if (copy_from_user
 977             (chip->data_buffer, (void __user *) buf, in_size)) {
 978                 mutex_unlock(&chip->buffer_mutex);
 979                 return -EFAULT;
 980         }
 981
 982         /* atomic tpm command send and result receive */
 983         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
 984
 985         atomic_set(&chip->data_pending, out_size);
 986         mutex_unlock(&chip->buffer_mutex);
 987
 988         /* Set a timeout by which the reader must come claim the result */
 989         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
 990
 991         return in_size;
 992 }
 993 EXPORT_SYMBOL_GPL(tpm_write);
 994
 995 ssize_t tpm_read(struct file *file, char __user *buf,
 996                  size_t size, loff_t *off)
 997 {
 998         struct tpm_chip *chip = file->private_data;
 999         int ret_size;
1000
1001         del_singleshot_timer_sync(&chip->user_read_timer);
1002         flush_scheduled_work();
1003         ret_size = atomic_read(&chip->data_pending);
1004         atomic_set(&chip->data_pending, 0);
1005         if (ret_size > 0) {     /* relay data */
1006                 if (size < ret_size)
1007                         ret_size = size;
1008
1009                 mutex_lock(&chip->buffer_mutex);
1010                 if (copy_to_user(buf, chip->data_buffer, ret_size))
1011                         ret_size = -EFAULT;
1012                 mutex_unlock(&chip->buffer_mutex);
1013         }
1014
1015         return ret_size;
1016 }
1017 EXPORT_SYMBOL_GPL(tpm_read);
1018
1019 void tpm_remove_hardware(struct device *dev)
1020 {
1021         struct tpm_chip *chip = dev_get_drvdata(dev);
1022
1023         if (chip == NULL) {
1024                 dev_err(dev, "No device data found\n");
1025                 return;
1026         }
1027
1028         spin_lock(&driver_lock);
1029
1030         list_del(&chip->list);
1031
1032         spin_unlock(&driver_lock);
1033
1034         misc_deregister(&chip->vendor.miscdev);
1035
1036         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1037         tpm_bios_log_teardown(chip->bios_dir);
1038
1039         /* write it this way to be explicit (chip->dev == dev) */
1040         put_device(chip->dev);
1041 }
1042 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1043
1044 /*
1045  * We are about to suspend. Save the TPM state
1046  * so that it can be restored.
1047  */
1048 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1049 {
1050         struct tpm_chip *chip = dev_get_drvdata(dev);
1051         u8 savestate[] = {
1052                 0, 193,         /* TPM_TAG_RQU_COMMAND */
1053                 0, 0, 0, 10,    /* blob length (in bytes) */
1054                 0, 0, 0, 152    /* TPM_ORD_SaveState */
1055         };
1056
1057         if (chip == NULL)
1058                 return -ENODEV;
1059
1060         tpm_transmit(chip, savestate, sizeof(savestate));
1061         return 0;
1062 }
1063 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1064
1065 /*
1066  * Resume from a power safe. The BIOS already restored
1067  * the TPM state.
1068  */
1069 int tpm_pm_resume(struct device *dev)
1070 {
1071         struct tpm_chip *chip = dev_get_drvdata(dev);
1072
1073         if (chip == NULL)
1074                 return -ENODEV;
1075
1076         return 0;
1077 }
1078 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1079
1080 /*
1081  * Once all references to platform device are down to 0,
1082  * release all allocated structures.
1083  * In case vendor provided release function,
1084  * call it too.
1085  */
1086 static void tpm_dev_release(struct device *dev)
1087 {
1088         struct tpm_chip *chip = dev_get_drvdata(dev);
1089
1090         if (chip->vendor.release)
1091                 chip->vendor.release(dev);
1092
1093         chip->release(dev);
1094
1095         clear_bit(chip->dev_num, dev_mask);
1096         kfree(chip->vendor.miscdev.name);
1097         kfree(chip);
1098 }
1099
1100 /*
1101  * Called from tpm_<specific>.c probe function only for devices
1102  * the driver has determined it should claim.  Prior to calling
1103  * this function the specific probe function has called pci_enable_device
1104  * upon errant exit from this function specific probe function should call
1105  * pci_disable_device
1106  */
1107 struct tpm_chip *tpm_register_hardware(struct device *dev, const struct tpm_vendor_specific
1108                                        *entry)
1109 {
1110 #define DEVNAME_SIZE 7
1111
1112         char *devname;
1113         struct tpm_chip *chip;
1114
1115         /* Driver specific per-device data */
1116         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1117         devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1118
1119         if (chip == NULL || devname == NULL) {
1120                 kfree(chip);
1121                 kfree(devname);
1122                 return NULL;
1123         }
1124
1125         mutex_init(&chip->buffer_mutex);
1126         mutex_init(&chip->tpm_mutex);
1127         INIT_LIST_HEAD(&chip->list);
1128
1129         INIT_WORK(&chip->work, timeout_work);
1130
1131         setup_timer(&chip->user_read_timer, user_reader_timeout,
1132                         (unsigned long)chip);
1133
1134         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1135
1136         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1137
1138         if (chip->dev_num >= TPM_NUM_DEVICES) {
1139                 dev_err(dev, "No available tpm device numbers\n");
1140                 kfree(chip);
1141                 return NULL;
1142         } else if (chip->dev_num == 0)
1143                 chip->vendor.miscdev.minor = TPM_MINOR;
1144         else
1145                 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1146
1147         set_bit(chip->dev_num, dev_mask);
1148
1149         scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1150         chip->vendor.miscdev.name = devname;
1151
1152         chip->vendor.miscdev.parent = dev;
1153         chip->dev = get_device(dev);
1154         chip->release = dev->release;
1155         dev->release = tpm_dev_release;
1156         dev_set_drvdata(dev, chip);
1157
1158         if (misc_register(&chip->vendor.miscdev)) {
1159                 dev_err(chip->dev,
1160                         "unable to misc_register %s, minor %d\n",
1161                         chip->vendor.miscdev.name,
1162                         chip->vendor.miscdev.minor);
1163                 put_device(chip->dev);
1164                 return NULL;
1165         }
1166
1167         spin_lock(&driver_lock);
1168
1169         list_add(&chip->list, &tpm_chip_list);
1170
1171         spin_unlock(&driver_lock);
1172
1173         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1174                 list_del(&chip->list);
1175                 misc_deregister(&chip->vendor.miscdev);
1176                 put_device(chip->dev);
1177                 return NULL;
1178         }
1179
1180         chip->bios_dir = tpm_bios_log_setup(devname);
1181
1182         return chip;
1183 }
1184 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1185
1186 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1187 MODULE_DESCRIPTION("TPM Driver");
1188 MODULE_VERSION("2.0");
1189 MODULE_LICENSE("GPL");