drivers/char/tpm/tpm.c

   1 /*
   2  * Copyright (C) 2004 IBM Corporation
   3  *
   4  * Authors:
   5  * Leendert van Doorn <leendert@watson.ibm.com>
   6  * Dave Safford <safford@watson.ibm.com>
   7  * Reiner Sailer <sailer@watson.ibm.com>
   8  * Kylene Hall <kjhall@us.ibm.com>
   9  *
  10  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
  11  *
  12  * Device driver for TCG/TCPA TPM (trusted platform module).
  13  * Specifications at www.trustedcomputinggroup.org
  14  *
  15  * This program is free software; you can redistribute it and/or
  16  * modify it under the terms of the GNU General Public License as
  17  * published by the Free Software Foundation, version 2 of the
  18  * License.
  19  *
  20  * Note, the TPM chip is not interrupt driven (only polling)
  21  * and can have very long timeouts (minutes!). Hence the unusual
  22  * calls to msleep.
  23  *
  24  */
  25
  26 #include <linux/poll.h>
  27 #include <linux/slab.h>
  28 #include <linux/mutex.h>
  29 #include <linux/spinlock.h>
  30 #include <linux/freezer.h>
  31
  32 #include "tpm.h"
  33 #include "tpm_eventlog.h"
  34
  35 enum tpm_duration {
  36         TPM_SHORT = 0,
  37         TPM_MEDIUM = 1,
  38         TPM_LONG = 2,
  39         TPM_UNDEFINED,
  40 };
  41
  42 #define TPM_MAX_ORDINAL 243
  43 #define TSC_MAX_ORDINAL 12
  44 #define TPM_PROTECTED_COMMAND 0x00
  45 #define TPM_CONNECTION_COMMAND 0x40
  46
  47 /*
  48  * Bug workaround - some TPM's don't flush the most
  49  * recently changed pcr on suspend, so force the flush
  50  * with an extend to the selected _unused_ non-volatile pcr.
  51  */
  52 static int tpm_suspend_pcr;
  53 module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644);
  54 MODULE_PARM_DESC(suspend_pcr,
  55                  "PCR to use for dummy writes to faciltate flush on suspend.");
  56
  57 static LIST_HEAD(tpm_chip_list);
  58 static DEFINE_SPINLOCK(driver_lock);
  59 static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
  60
  61 /*
  62  * Array with one entry per ordinal defining the maximum amount
  63  * of time the chip could take to return the result.  The ordinal
  64  * designation of short, medium or long is defined in a table in
  65  * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
  66  * values of the SHORT, MEDIUM, and LONG durations are retrieved
  67  * from the chip during initialization with a call to tpm_get_timeouts.
  68  */
  69 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
  70         TPM_UNDEFINED,          /* 0 */
  71         TPM_UNDEFINED,
  72         TPM_UNDEFINED,
  73         TPM_UNDEFINED,
  74         TPM_UNDEFINED,
  75         TPM_UNDEFINED,          /* 5 */
  76         TPM_UNDEFINED,
  77         TPM_UNDEFINED,
  78         TPM_UNDEFINED,
  79         TPM_UNDEFINED,
  80         TPM_SHORT,              /* 10 */
  81         TPM_SHORT,
  82         TPM_MEDIUM,
  83         TPM_LONG,
  84         TPM_LONG,
  85         TPM_MEDIUM,             /* 15 */
  86         TPM_SHORT,
  87         TPM_SHORT,
  88         TPM_MEDIUM,
  89         TPM_LONG,
  90         TPM_SHORT,              /* 20 */
  91         TPM_SHORT,
  92         TPM_MEDIUM,
  93         TPM_MEDIUM,
  94         TPM_MEDIUM,
  95         TPM_SHORT,              /* 25 */
  96         TPM_SHORT,
  97         TPM_MEDIUM,
  98         TPM_SHORT,
  99         TPM_SHORT,
 100         TPM_MEDIUM,             /* 30 */
 101         TPM_LONG,
 102         TPM_MEDIUM,
 103         TPM_SHORT,
 104         TPM_SHORT,
 105         TPM_SHORT,              /* 35 */
 106         TPM_MEDIUM,
 107         TPM_MEDIUM,
 108         TPM_UNDEFINED,
 109         TPM_UNDEFINED,
 110         TPM_MEDIUM,             /* 40 */
 111         TPM_LONG,
 112         TPM_MEDIUM,
 113         TPM_SHORT,
 114         TPM_SHORT,
 115         TPM_SHORT,              /* 45 */
 116         TPM_SHORT,
 117         TPM_SHORT,
 118         TPM_SHORT,
 119         TPM_LONG,
 120         TPM_MEDIUM,             /* 50 */
 121         TPM_MEDIUM,
 122         TPM_UNDEFINED,
 123         TPM_UNDEFINED,
 124         TPM_UNDEFINED,
 125         TPM_UNDEFINED,          /* 55 */
 126         TPM_UNDEFINED,
 127         TPM_UNDEFINED,
 128         TPM_UNDEFINED,
 129         TPM_UNDEFINED,
 130         TPM_MEDIUM,             /* 60 */
 131         TPM_MEDIUM,
 132         TPM_MEDIUM,
 133         TPM_SHORT,
 134         TPM_SHORT,
 135         TPM_MEDIUM,             /* 65 */
 136         TPM_UNDEFINED,
 137         TPM_UNDEFINED,
 138         TPM_UNDEFINED,
 139         TPM_UNDEFINED,
 140         TPM_SHORT,              /* 70 */
 141         TPM_SHORT,
 142         TPM_UNDEFINED,
 143         TPM_UNDEFINED,
 144         TPM_UNDEFINED,
 145         TPM_UNDEFINED,          /* 75 */
 146         TPM_UNDEFINED,
 147         TPM_UNDEFINED,
 148         TPM_UNDEFINED,
 149         TPM_UNDEFINED,
 150         TPM_LONG,               /* 80 */
 151         TPM_UNDEFINED,
 152         TPM_MEDIUM,
 153         TPM_LONG,
 154         TPM_SHORT,
 155         TPM_UNDEFINED,          /* 85 */
 156         TPM_UNDEFINED,
 157         TPM_UNDEFINED,
 158         TPM_UNDEFINED,
 159         TPM_UNDEFINED,
 160         TPM_SHORT,              /* 90 */
 161         TPM_SHORT,
 162         TPM_SHORT,
 163         TPM_SHORT,
 164         TPM_SHORT,
 165         TPM_UNDEFINED,          /* 95 */
 166         TPM_UNDEFINED,
 167         TPM_UNDEFINED,
 168         TPM_UNDEFINED,
 169         TPM_UNDEFINED,
 170         TPM_MEDIUM,             /* 100 */
 171         TPM_SHORT,
 172         TPM_SHORT,
 173         TPM_UNDEFINED,
 174         TPM_UNDEFINED,
 175         TPM_UNDEFINED,          /* 105 */
 176         TPM_UNDEFINED,
 177         TPM_UNDEFINED,
 178         TPM_UNDEFINED,
 179         TPM_UNDEFINED,
 180         TPM_SHORT,              /* 110 */
 181         TPM_SHORT,
 182         TPM_SHORT,
 183         TPM_SHORT,
 184         TPM_SHORT,
 185         TPM_SHORT,              /* 115 */
 186         TPM_SHORT,
 187         TPM_SHORT,
 188         TPM_UNDEFINED,
 189         TPM_UNDEFINED,
 190         TPM_LONG,               /* 120 */
 191         TPM_LONG,
 192         TPM_MEDIUM,
 193         TPM_UNDEFINED,
 194         TPM_SHORT,
 195         TPM_SHORT,              /* 125 */
 196         TPM_SHORT,
 197         TPM_LONG,
 198         TPM_SHORT,
 199         TPM_SHORT,
 200         TPM_SHORT,              /* 130 */
 201         TPM_MEDIUM,
 202         TPM_UNDEFINED,
 203         TPM_SHORT,
 204         TPM_MEDIUM,
 205         TPM_UNDEFINED,          /* 135 */
 206         TPM_UNDEFINED,
 207         TPM_UNDEFINED,
 208         TPM_UNDEFINED,
 209         TPM_UNDEFINED,
 210         TPM_SHORT,              /* 140 */
 211         TPM_SHORT,
 212         TPM_UNDEFINED,
 213         TPM_UNDEFINED,
 214         TPM_UNDEFINED,
 215         TPM_UNDEFINED,          /* 145 */
 216         TPM_UNDEFINED,
 217         TPM_UNDEFINED,
 218         TPM_UNDEFINED,
 219         TPM_UNDEFINED,
 220         TPM_SHORT,              /* 150 */
 221         TPM_MEDIUM,
 222         TPM_MEDIUM,
 223         TPM_SHORT,
 224         TPM_SHORT,
 225         TPM_UNDEFINED,          /* 155 */
 226         TPM_UNDEFINED,
 227         TPM_UNDEFINED,
 228         TPM_UNDEFINED,
 229         TPM_UNDEFINED,
 230         TPM_SHORT,              /* 160 */
 231         TPM_SHORT,
 232         TPM_SHORT,
 233         TPM_SHORT,
 234         TPM_UNDEFINED,
 235         TPM_UNDEFINED,          /* 165 */
 236         TPM_UNDEFINED,
 237         TPM_UNDEFINED,
 238         TPM_UNDEFINED,
 239         TPM_UNDEFINED,
 240         TPM_LONG,               /* 170 */
 241         TPM_UNDEFINED,
 242         TPM_UNDEFINED,
 243         TPM_UNDEFINED,
 244         TPM_UNDEFINED,
 245         TPM_UNDEFINED,          /* 175 */
 246         TPM_UNDEFINED,
 247         TPM_UNDEFINED,
 248         TPM_UNDEFINED,
 249         TPM_UNDEFINED,
 250         TPM_MEDIUM,             /* 180 */
 251         TPM_SHORT,
 252         TPM_MEDIUM,
 253         TPM_MEDIUM,
 254         TPM_MEDIUM,
 255         TPM_MEDIUM,             /* 185 */
 256         TPM_SHORT,
 257         TPM_UNDEFINED,
 258         TPM_UNDEFINED,
 259         TPM_UNDEFINED,
 260         TPM_UNDEFINED,          /* 190 */
 261         TPM_UNDEFINED,
 262         TPM_UNDEFINED,
 263         TPM_UNDEFINED,
 264         TPM_UNDEFINED,
 265         TPM_UNDEFINED,          /* 195 */
 266         TPM_UNDEFINED,
 267         TPM_UNDEFINED,
 268         TPM_UNDEFINED,
 269         TPM_UNDEFINED,
 270         TPM_SHORT,              /* 200 */
 271         TPM_UNDEFINED,
 272         TPM_UNDEFINED,
 273         TPM_UNDEFINED,
 274         TPM_SHORT,
 275         TPM_SHORT,              /* 205 */
 276         TPM_SHORT,
 277         TPM_SHORT,
 278         TPM_SHORT,
 279         TPM_SHORT,
 280         TPM_MEDIUM,             /* 210 */
 281         TPM_UNDEFINED,
 282         TPM_MEDIUM,
 283         TPM_MEDIUM,
 284         TPM_MEDIUM,
 285         TPM_UNDEFINED,          /* 215 */
 286         TPM_MEDIUM,
 287         TPM_UNDEFINED,
 288         TPM_UNDEFINED,
 289         TPM_SHORT,
 290         TPM_SHORT,              /* 220 */
 291         TPM_SHORT,
 292         TPM_SHORT,
 293         TPM_SHORT,
 294         TPM_SHORT,
 295         TPM_UNDEFINED,          /* 225 */
 296         TPM_UNDEFINED,
 297         TPM_UNDEFINED,
 298         TPM_UNDEFINED,
 299         TPM_UNDEFINED,
 300         TPM_SHORT,              /* 230 */
 301         TPM_LONG,
 302         TPM_MEDIUM,
 303         TPM_UNDEFINED,
 304         TPM_UNDEFINED,
 305         TPM_UNDEFINED,          /* 235 */
 306         TPM_UNDEFINED,
 307         TPM_UNDEFINED,
 308         TPM_UNDEFINED,
 309         TPM_UNDEFINED,
 310         TPM_SHORT,              /* 240 */
 311         TPM_UNDEFINED,
 312         TPM_MEDIUM,
 313 };
 314
 315 static void user_reader_timeout(unsigned long ptr)
 316 {
 317         struct tpm_chip *chip = (struct tpm_chip *) ptr;
 318
 319         schedule_work(&chip->work);
 320 }
 321
 322 static void timeout_work(struct work_struct *work)
 323 {
 324         struct tpm_chip *chip = container_of(work, struct tpm_chip, work);
 325
 326         mutex_lock(&chip->buffer_mutex);
 327         atomic_set(&chip->data_pending, 0);
 328         memset(chip->data_buffer, 0, TPM_BUFSIZE);
 329         mutex_unlock(&chip->buffer_mutex);
 330 }
 331
 332 /*
 333  * Returns max number of jiffies to wait
 334  */
 335 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
 336                                            u32 ordinal)
 337 {
 338         int duration_idx = TPM_UNDEFINED;
 339         int duration = 0;
 340         u8 category = (ordinal >> 24) & 0xFF;
 341
 342         if ((category == TPM_PROTECTED_COMMAND && ordinal < TPM_MAX_ORDINAL) ||
 343             (category == TPM_CONNECTION_COMMAND && ordinal < TSC_MAX_ORDINAL))
 344                 duration_idx = tpm_ordinal_duration[ordinal];
 345
 346         if (duration_idx != TPM_UNDEFINED)
 347                 duration = chip->vendor.duration[duration_idx];
 348         if (duration <= 0)
 349                 return 2 * 60 * HZ;
 350         else
 351                 return duration;
 352 }
 353 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 354
 355 /*
 356  * Internal kernel interface to transmit TPM commands
 357  */
 358 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
 359                             size_t bufsiz)
 360 {
 361         ssize_t rc;
 362         u32 count, ordinal;
 363         unsigned long stop;
 364
 365         if (bufsiz > TPM_BUFSIZE)
 366                 bufsiz = TPM_BUFSIZE;
 367
 368         count = be32_to_cpu(*((__be32 *) (buf + 2)));
 369         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
 370         if (count == 0)
 371                 return -ENODATA;
 372         if (count > bufsiz) {
 373                 dev_err(chip->dev,
 374                         "invalid count value %x %zx \n", count, bufsiz);
 375                 return -E2BIG;
 376         }
 377
 378         mutex_lock(&chip->tpm_mutex);
 379
 380         if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
 381                 dev_err(chip->dev,
 382                         "tpm_transmit: tpm_send: error %zd\n", rc);
 383                 goto out;
 384         }
 385
 386         if (chip->vendor.irq)
 387                 goto out_recv;
 388
 389         stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
 390         do {
 391                 u8 status = chip->vendor.status(chip);
 392                 if ((status & chip->vendor.req_complete_mask) ==
 393                     chip->vendor.req_complete_val)
 394                         goto out_recv;
 395
 396                 if (chip->vendor.req_canceled(chip, status)) {
 397                         dev_err(chip->dev, "Operation Canceled\n");
 398                         rc = -ECANCELED;
 399                         goto out;
 400                 }
 401
 402                 msleep(TPM_TIMEOUT);    /* CHECK */
 403                 rmb();
 404         } while (time_before(jiffies, stop));
 405
 406         chip->vendor.cancel(chip);
 407         dev_err(chip->dev, "Operation Timed out\n");
 408         rc = -ETIME;
 409         goto out;
 410
 411 out_recv:
 412         rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
 413         if (rc < 0)
 414                 dev_err(chip->dev,
 415                         "tpm_transmit: tpm_recv: error %zd\n", rc);
 416 out:
 417         mutex_unlock(&chip->tpm_mutex);
 418         return rc;
 419 }
 420
 421 #define TPM_DIGEST_SIZE 20
 422 #define TPM_RET_CODE_IDX 6
 423
 424 enum tpm_capabilities {
 425         TPM_CAP_FLAG = cpu_to_be32(4),
 426         TPM_CAP_PROP = cpu_to_be32(5),
 427         CAP_VERSION_1_1 = cpu_to_be32(0x06),
 428         CAP_VERSION_1_2 = cpu_to_be32(0x1A)
 429 };
 430
 431 enum tpm_sub_capabilities {
 432         TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
 433         TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
 434         TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
 435         TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
 436         TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
 437         TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
 438         TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
 439
 440 };
 441
 442 static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
 443                             int len, const char *desc)
 444 {
 445         int err;
 446
 447         len = tpm_transmit(chip,(u8 *) cmd, len);
 448         if (len <  0)
 449                 return len;
 450         else if (len < TPM_HEADER_SIZE)
 451                 return -EFAULT;
 452
 453         err = be32_to_cpu(cmd->header.out.return_code);
 454         if (err != 0 && desc)
 455                 dev_err(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
 456
 457         return err;
 458 }
 459
 460 #define TPM_INTERNAL_RESULT_SIZE 200
 461 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
 462 #define TPM_ORD_GET_CAP cpu_to_be32(101)
 463 #define TPM_ORD_GET_RANDOM cpu_to_be32(70)
 464
 465 static const struct tpm_input_header tpm_getcap_header = {
 466         .tag = TPM_TAG_RQU_COMMAND,
 467         .length = cpu_to_be32(22),
 468         .ordinal = TPM_ORD_GET_CAP
 469 };
 470
 471 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
 472                    const char *desc)
 473 {
 474         struct tpm_cmd_t tpm_cmd;
 475         int rc;
 476         struct tpm_chip *chip = dev_get_drvdata(dev);
 477
 478         tpm_cmd.header.in = tpm_getcap_header;
 479         if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
 480                 tpm_cmd.params.getcap_in.cap = subcap_id;
 481                 /*subcap field not necessary */
 482                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
 483                 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
 484         } else {
 485                 if (subcap_id == TPM_CAP_FLAG_PERM ||
 486                     subcap_id == TPM_CAP_FLAG_VOL)
 487                         tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
 488                 else
 489                         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 490                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 491                 tpm_cmd.params.getcap_in.subcap = subcap_id;
 492         }
 493         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
 494         if (!rc)
 495                 *cap = tpm_cmd.params.getcap_out.cap;
 496         return rc;
 497 }
 498
 499 void tpm_gen_interrupt(struct tpm_chip *chip)
 500 {
 501         struct  tpm_cmd_t tpm_cmd;
 502         ssize_t rc;
 503
 504         tpm_cmd.header.in = tpm_getcap_header;
 505         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 506         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 507         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 508
 509         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 510                         "attempting to determine the timeouts");
 511 }
 512 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
 513
 514 #define TPM_ORD_STARTUP cpu_to_be32(153)
 515 #define TPM_ST_CLEAR cpu_to_be16(1)
 516 #define TPM_ST_STATE cpu_to_be16(2)
 517 #define TPM_ST_DEACTIVATED cpu_to_be16(3)
 518 static const struct tpm_input_header tpm_startup_header = {
 519         .tag = TPM_TAG_RQU_COMMAND,
 520         .length = cpu_to_be32(12),
 521         .ordinal = TPM_ORD_STARTUP
 522 };
 523
 524 static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
 525 {
 526         struct tpm_cmd_t start_cmd;
 527         start_cmd.header.in = tpm_startup_header;
 528         start_cmd.params.startup_in.startup_type = startup_type;
 529         return transmit_cmd(chip, &start_cmd, TPM_INTERNAL_RESULT_SIZE,
 530                             "attempting to start the TPM");
 531 }
 532
 533 int tpm_get_timeouts(struct tpm_chip *chip)
 534 {
 535         struct tpm_cmd_t tpm_cmd;
 536         unsigned long new_timeout[4];
 537         unsigned long old_timeout[4];
 538         struct duration_t *duration_cap;
 539         ssize_t rc;
 540
 541         tpm_cmd.header.in = tpm_getcap_header;
 542         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 543         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 544         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 545         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, NULL);
 546
 547         if (rc == TPM_ERR_INVALID_POSTINIT) {
 548                 /* The TPM is not started, we are the first to talk to it.
 549                    Execute a startup command. */
 550                 dev_info(chip->dev, "Issuing TPM_STARTUP");
 551                 if (tpm_startup(chip, TPM_ST_CLEAR))
 552                         return rc;
 553
 554                 tpm_cmd.header.in = tpm_getcap_header;
 555                 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 556                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 557                 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 558                 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 559                                   NULL);
 560         }
 561         if (rc) {
 562                 dev_err(chip->dev,
 563                         "A TPM error (%zd) occurred attempting to determine the timeouts\n",
 564                         rc);
 565                 goto duration;
 566         }
 567
 568         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 569             be32_to_cpu(tpm_cmd.header.out.length)
 570             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
 571                 return -EINVAL;
 572
 573         old_timeout[0] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.a);
 574         old_timeout[1] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.b);
 575         old_timeout[2] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.c);
 576         old_timeout[3] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.d);
 577         memcpy(new_timeout, old_timeout, sizeof(new_timeout));
 578
 579         /*
 580          * Provide ability for vendor overrides of timeout values in case
 581          * of misreporting.
 582          */
 583         if (chip->vendor.update_timeouts != NULL)
 584                 chip->vendor.timeout_adjusted =
 585                         chip->vendor.update_timeouts(chip, new_timeout);
 586
 587         if (!chip->vendor.timeout_adjusted) {
 588                 /* Don't overwrite default if value is 0 */
 589                 if (new_timeout[0] != 0 && new_timeout[0] < 1000) {
 590                         int i;
 591
 592                         /* timeouts in msec rather usec */
 593                         for (i = 0; i != ARRAY_SIZE(new_timeout); i++)
 594                                 new_timeout[i] *= 1000;
 595                         chip->vendor.timeout_adjusted = true;
 596                 }
 597         }
 598
 599         /* Report adjusted timeouts */
 600         if (chip->vendor.timeout_adjusted) {
 601                 dev_info(chip->dev,
 602                          HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n",
 603                          old_timeout[0], new_timeout[0],
 604                          old_timeout[1], new_timeout[1],
 605                          old_timeout[2], new_timeout[2],
 606                          old_timeout[3], new_timeout[3]);
 607         }
 608
 609         chip->vendor.timeout_a = usecs_to_jiffies(new_timeout[0]);
 610         chip->vendor.timeout_b = usecs_to_jiffies(new_timeout[1]);
 611         chip->vendor.timeout_c = usecs_to_jiffies(new_timeout[2]);
 612         chip->vendor.timeout_d = usecs_to_jiffies(new_timeout[3]);
 613
 614 duration:
 615         tpm_cmd.header.in = tpm_getcap_header;
 616         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 617         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 618         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
 619
 620         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 621                         "attempting to determine the durations");
 622         if (rc)
 623                 return rc;
 624
 625         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 626             be32_to_cpu(tpm_cmd.header.out.length)
 627             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
 628                 return -EINVAL;
 629
 630         duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
 631         chip->vendor.duration[TPM_SHORT] =
 632             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
 633         chip->vendor.duration[TPM_MEDIUM] =
 634             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
 635         chip->vendor.duration[TPM_LONG] =
 636             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
 637
 638         /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
 639          * value wrong and apparently reports msecs rather than usecs. So we
 640          * fix up the resulting too-small TPM_SHORT value to make things work.
 641          * We also scale the TPM_MEDIUM and -_LONG values by 1000.
 642          */
 643         if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
 644                 chip->vendor.duration[TPM_SHORT] = HZ;
 645                 chip->vendor.duration[TPM_MEDIUM] *= 1000;
 646                 chip->vendor.duration[TPM_LONG] *= 1000;
 647                 chip->vendor.duration_adjusted = true;
 648                 dev_info(chip->dev, "Adjusting TPM timeout parameters.");
 649         }
 650         return 0;
 651 }
 652 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
 653
 654 #define TPM_ORD_CONTINUE_SELFTEST 83
 655 #define CONTINUE_SELFTEST_RESULT_SIZE 10
 656
 657 static struct tpm_input_header continue_selftest_header = {
 658         .tag = TPM_TAG_RQU_COMMAND,
 659         .length = cpu_to_be32(10),
 660         .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
 661 };
 662
 663 /**
 664  * tpm_continue_selftest -- run TPM's selftest
 665  * @chip: TPM chip to use
 666  *
 667  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
 668  * a TPM error code.
 669  */
 670 static int tpm_continue_selftest(struct tpm_chip *chip)
 671 {
 672         int rc;
 673         struct tpm_cmd_t cmd;
 674
 675         cmd.header.in = continue_selftest_header;
 676         rc = transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
 677                           "continue selftest");
 678         return rc;
 679 }
 680
 681 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
 682                         char *buf)
 683 {
 684         cap_t cap;
 685         ssize_t rc;
 686
 687         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 688                          "attempting to determine the permanent enabled state");
 689         if (rc)
 690                 return 0;
 691
 692         rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
 693         return rc;
 694 }
 695 EXPORT_SYMBOL_GPL(tpm_show_enabled);
 696
 697 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
 698                         char *buf)
 699 {
 700         cap_t cap;
 701         ssize_t rc;
 702
 703         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 704                          "attempting to determine the permanent active state");
 705         if (rc)
 706                 return 0;
 707
 708         rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
 709         return rc;
 710 }
 711 EXPORT_SYMBOL_GPL(tpm_show_active);
 712
 713 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
 714                         char *buf)
 715 {
 716         cap_t cap;
 717         ssize_t rc;
 718
 719         rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
 720                          "attempting to determine the owner state");
 721         if (rc)
 722                 return 0;
 723
 724         rc = sprintf(buf, "%d\n", cap.owned);
 725         return rc;
 726 }
 727 EXPORT_SYMBOL_GPL(tpm_show_owned);
 728
 729 ssize_t tpm_show_temp_deactivated(struct device * dev,
 730                                 struct device_attribute * attr, char *buf)
 731 {
 732         cap_t cap;
 733         ssize_t rc;
 734
 735         rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
 736                          "attempting to determine the temporary state");
 737         if (rc)
 738                 return 0;
 739
 740         rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
 741         return rc;
 742 }
 743 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
 744
 745 /*
 746  * tpm_chip_find_get - return tpm_chip for given chip number
 747  */
 748 static struct tpm_chip *tpm_chip_find_get(int chip_num)
 749 {
 750         struct tpm_chip *pos, *chip = NULL;
 751
 752         rcu_read_lock();
 753         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
 754                 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
 755                         continue;
 756
 757                 if (try_module_get(pos->dev->driver->owner)) {
 758                         chip = pos;
 759                         break;
 760                 }
 761         }
 762         rcu_read_unlock();
 763         return chip;
 764 }
 765
 766 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
 767 #define READ_PCR_RESULT_SIZE 30
 768 static struct tpm_input_header pcrread_header = {
 769         .tag = TPM_TAG_RQU_COMMAND,
 770         .length = cpu_to_be32(14),
 771         .ordinal = TPM_ORDINAL_PCRREAD
 772 };
 773
 774 static int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 775 {
 776         int rc;
 777         struct tpm_cmd_t cmd;
 778
 779         cmd.header.in = pcrread_header;
 780         cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
 781         rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
 782                           "attempting to read a pcr value");
 783
 784         if (rc == 0)
 785                 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
 786                        TPM_DIGEST_SIZE);
 787         return rc;
 788 }
 789
 790 /**
 791  * tpm_pcr_read - read a pcr value
 792  * @chip_num:   tpm idx # or ANY
 793  * @pcr_idx:    pcr idx to retrieve
 794  * @res_buf:    TPM_PCR value
 795  *              size of res_buf is 20 bytes (or NULL if you don't care)
 796  *
 797  * The TPM driver should be built-in, but for whatever reason it
 798  * isn't, protect against the chip disappearing, by incrementing
 799  * the module usage count.
 800  */
 801 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
 802 {
 803         struct tpm_chip *chip;
 804         int rc;
 805
 806         chip = tpm_chip_find_get(chip_num);
 807         if (chip == NULL)
 808                 return -ENODEV;
 809         rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
 810         tpm_chip_put(chip);
 811         return rc;
 812 }
 813 EXPORT_SYMBOL_GPL(tpm_pcr_read);
 814
 815 /**
 816  * tpm_pcr_extend - extend pcr value with hash
 817  * @chip_num:   tpm idx # or AN&
 818  * @pcr_idx:    pcr idx to extend
 819  * @hash:       hash value used to extend pcr value
 820  *
 821  * The TPM driver should be built-in, but for whatever reason it
 822  * isn't, protect against the chip disappearing, by incrementing
 823  * the module usage count.
 824  */
 825 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
 826 #define EXTEND_PCR_RESULT_SIZE 34
 827 static struct tpm_input_header pcrextend_header = {
 828         .tag = TPM_TAG_RQU_COMMAND,
 829         .length = cpu_to_be32(34),
 830         .ordinal = TPM_ORD_PCR_EXTEND
 831 };
 832
 833 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
 834 {
 835         struct tpm_cmd_t cmd;
 836         int rc;
 837         struct tpm_chip *chip;
 838
 839         chip = tpm_chip_find_get(chip_num);
 840         if (chip == NULL)
 841                 return -ENODEV;
 842
 843         cmd.header.in = pcrextend_header;
 844         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
 845         memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
 846         rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
 847                           "attempting extend a PCR value");
 848
 849         tpm_chip_put(chip);
 850         return rc;
 851 }
 852 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
 853
 854 /**
 855  * tpm_do_selftest - have the TPM continue its selftest and wait until it
 856  *                   can receive further commands
 857  * @chip: TPM chip to use
 858  *
 859  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
 860  * a TPM error code.
 861  */
 862 int tpm_do_selftest(struct tpm_chip *chip)
 863 {
 864         int rc;
 865         unsigned int loops;
 866         unsigned int delay_msec = 100;
 867         unsigned long duration;
 868         struct tpm_cmd_t cmd;
 869
 870         duration = tpm_calc_ordinal_duration(chip,
 871                                              TPM_ORD_CONTINUE_SELFTEST);
 872
 873         loops = jiffies_to_msecs(duration) / delay_msec;
 874
 875         rc = tpm_continue_selftest(chip);
 876         /* This may fail if there was no TPM driver during a suspend/resume
 877          * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
 878          */
 879         if (rc)
 880                 return rc;
 881
 882         do {
 883                 /* Attempt to read a PCR value */
 884                 cmd.header.in = pcrread_header;
 885                 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(0);
 886                 rc = tpm_transmit(chip, (u8 *) &cmd, READ_PCR_RESULT_SIZE);
 887                 /* Some buggy TPMs will not respond to tpm_tis_ready() for
 888                  * around 300ms while the self test is ongoing, keep trying
 889                  * until the self test duration expires. */
 890                 if (rc == -ETIME) {
 891                         dev_info(chip->dev, HW_ERR "TPM command timed out during continue self test");
 892                         msleep(delay_msec);
 893                         continue;
 894                 }
 895
 896                 if (rc < TPM_HEADER_SIZE)
 897                         return -EFAULT;
 898
 899                 rc = be32_to_cpu(cmd.header.out.return_code);
 900                 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
 901                         dev_info(chip->dev,
 902                                  "TPM is disabled/deactivated (0x%X)\n", rc);
 903                         /* TPM is disabled and/or deactivated; driver can
 904                          * proceed and TPM does handle commands for
 905                          * suspend/resume correctly
 906                          */
 907                         return 0;
 908                 }
 909                 if (rc != TPM_WARN_DOING_SELFTEST)
 910                         return rc;
 911                 msleep(delay_msec);
 912         } while (--loops > 0);
 913
 914         return rc;
 915 }
 916 EXPORT_SYMBOL_GPL(tpm_do_selftest);
 917
 918 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
 919 {
 920         struct tpm_chip *chip;
 921         int rc;
 922
 923         chip = tpm_chip_find_get(chip_num);
 924         if (chip == NULL)
 925                 return -ENODEV;
 926
 927         rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
 928
 929         tpm_chip_put(chip);
 930         return rc;
 931 }
 932 EXPORT_SYMBOL_GPL(tpm_send);
 933
 934 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
 935                       char *buf)
 936 {
 937         cap_t cap;
 938         u8 digest[TPM_DIGEST_SIZE];
 939         ssize_t rc;
 940         int i, j, num_pcrs;
 941         char *str = buf;
 942         struct tpm_chip *chip = dev_get_drvdata(dev);
 943
 944         rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
 945                         "attempting to determine the number of PCRS");
 946         if (rc)
 947                 return 0;
 948
 949         num_pcrs = be32_to_cpu(cap.num_pcrs);
 950         for (i = 0; i < num_pcrs; i++) {
 951                 rc = __tpm_pcr_read(chip, i, digest);
 952                 if (rc)
 953                         break;
 954                 str += sprintf(str, "PCR-%02d: ", i);
 955                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
 956                         str += sprintf(str, "%02X ", digest[j]);
 957                 str += sprintf(str, "\n");
 958         }
 959         return str - buf;
 960 }
 961 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 962
 963 #define  READ_PUBEK_RESULT_SIZE 314
 964 #define TPM_ORD_READPUBEK cpu_to_be32(124)
 965 static struct tpm_input_header tpm_readpubek_header = {
 966         .tag = TPM_TAG_RQU_COMMAND,
 967         .length = cpu_to_be32(30),
 968         .ordinal = TPM_ORD_READPUBEK
 969 };
 970
 971 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
 972                        char *buf)
 973 {
 974         u8 *data;
 975         struct tpm_cmd_t tpm_cmd;
 976         ssize_t err;
 977         int i, rc;
 978         char *str = buf;
 979
 980         struct tpm_chip *chip = dev_get_drvdata(dev);
 981
 982         tpm_cmd.header.in = tpm_readpubek_header;
 983         err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
 984                         "attempting to read the PUBEK");
 985         if (err)
 986                 goto out;
 987
 988         /*
 989            ignore header 10 bytes
 990            algorithm 32 bits (1 == RSA )
 991            encscheme 16 bits
 992            sigscheme 16 bits
 993            parameters (RSA 12->bytes: keybit, #primes, expbit)
 994            keylenbytes 32 bits
 995            256 byte modulus
 996            ignore checksum 20 bytes
 997          */
 998         data = tpm_cmd.params.readpubek_out_buffer;
 999         str +=
1000             sprintf(str,
1001                     "Algorithm: %02X %02X %02X %02X\n"
1002                     "Encscheme: %02X %02X\n"
1003                     "Sigscheme: %02X %02X\n"
1004                     "Parameters: %02X %02X %02X %02X "
1005                     "%02X %02X %02X %02X "
1006                     "%02X %02X %02X %02X\n"
1007                     "Modulus length: %d\n"
1008                     "Modulus:\n",
1009                     data[0], data[1], data[2], data[3],
1010                     data[4], data[5],
1011                     data[6], data[7],
1012                     data[12], data[13], data[14], data[15],
1013                     data[16], data[17], data[18], data[19],
1014                     data[20], data[21], data[22], data[23],
1015                     be32_to_cpu(*((__be32 *) (data + 24))));
1016
1017         for (i = 0; i < 256; i++) {
1018                 str += sprintf(str, "%02X ", data[i + 28]);
1019                 if ((i + 1) % 16 == 0)
1020                         str += sprintf(str, "\n");
1021         }
1022 out:
1023         rc = str - buf;
1024         return rc;
1025 }
1026 EXPORT_SYMBOL_GPL(tpm_show_pubek);
1027
1028
1029 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
1030                       char *buf)
1031 {
1032         cap_t cap;
1033         ssize_t rc;
1034         char *str = buf;
1035
1036         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
1037                         "attempting to determine the manufacturer");
1038         if (rc)
1039                 return 0;
1040         str += sprintf(str, "Manufacturer: 0x%x\n",
1041                        be32_to_cpu(cap.manufacturer_id));
1042
1043         rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
1044                         "attempting to determine the 1.1 version");
1045         if (rc)
1046                 return 0;
1047         str += sprintf(str,
1048                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
1049                        cap.tpm_version.Major, cap.tpm_version.Minor,
1050                        cap.tpm_version.revMajor, cap.tpm_version.revMinor);
1051         return str - buf;
1052 }
1053 EXPORT_SYMBOL_GPL(tpm_show_caps);
1054
1055 ssize_t tpm_show_caps_1_2(struct device * dev,
1056                           struct device_attribute * attr, char *buf)
1057 {
1058         cap_t cap;
1059         ssize_t rc;
1060         char *str = buf;
1061
1062         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
1063                         "attempting to determine the manufacturer");
1064         if (rc)
1065                 return 0;
1066         str += sprintf(str, "Manufacturer: 0x%x\n",
1067                        be32_to_cpu(cap.manufacturer_id));
1068         rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
1069                          "attempting to determine the 1.2 version");
1070         if (rc)
1071                 return 0;
1072         str += sprintf(str,
1073                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
1074                        cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
1075                        cap.tpm_version_1_2.revMajor,
1076                        cap.tpm_version_1_2.revMinor);
1077         return str - buf;
1078 }
1079 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
1080
1081 ssize_t tpm_show_durations(struct device *dev, struct device_attribute *attr,
1082                           char *buf)
1083 {
1084         struct tpm_chip *chip = dev_get_drvdata(dev);
1085
1086         if (chip->vendor.duration[TPM_LONG] == 0)
1087                 return 0;
1088
1089         return sprintf(buf, "%d %d %d [%s]\n",
1090                        jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
1091                        jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
1092                        jiffies_to_usecs(chip->vendor.duration[TPM_LONG]),
1093                        chip->vendor.duration_adjusted
1094                        ? "adjusted" : "original");
1095 }
1096 EXPORT_SYMBOL_GPL(tpm_show_durations);
1097
1098 ssize_t tpm_show_timeouts(struct device *dev, struct device_attribute *attr,
1099                           char *buf)
1100 {
1101         struct tpm_chip *chip = dev_get_drvdata(dev);
1102
1103         return sprintf(buf, "%d %d %d %d [%s]\n",
1104                        jiffies_to_usecs(chip->vendor.timeout_a),
1105                        jiffies_to_usecs(chip->vendor.timeout_b),
1106                        jiffies_to_usecs(chip->vendor.timeout_c),
1107                        jiffies_to_usecs(chip->vendor.timeout_d),
1108                        chip->vendor.timeout_adjusted
1109                        ? "adjusted" : "original");
1110 }
1111 EXPORT_SYMBOL_GPL(tpm_show_timeouts);
1112
1113 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
1114                         const char *buf, size_t count)
1115 {
1116         struct tpm_chip *chip = dev_get_drvdata(dev);
1117         if (chip == NULL)
1118                 return 0;
1119
1120         chip->vendor.cancel(chip);
1121         return count;
1122 }
1123 EXPORT_SYMBOL_GPL(tpm_store_cancel);
1124
1125 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask, bool check_cancel,
1126                                    bool *canceled)
1127 {
1128         u8 status = chip->vendor.status(chip);
1129
1130         *canceled = false;
1131         if ((status & mask) == mask)
1132                 return true;
1133         if (check_cancel && chip->vendor.req_canceled(chip, status)) {
1134                 *canceled = true;
1135                 return true;
1136         }
1137         return false;
1138 }
1139
1140 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
1141                       wait_queue_head_t *queue, bool check_cancel)
1142 {
1143         unsigned long stop;
1144         long rc;
1145         u8 status;
1146         bool canceled = false;
1147
1148         /* check current status */
1149         status = chip->vendor.status(chip);
1150         if ((status & mask) == mask)
1151                 return 0;
1152
1153         stop = jiffies + timeout;
1154
1155         if (chip->vendor.irq) {
1156 again:
1157                 timeout = stop - jiffies;
1158                 if ((long)timeout <= 0)
1159                         return -ETIME;
1160                 rc = wait_event_interruptible_timeout(*queue,
1161                         wait_for_tpm_stat_cond(chip, mask, check_cancel,
1162                                                &canceled),
1163                         timeout);
1164                 if (rc > 0) {
1165                         if (canceled)
1166                                 return -ECANCELED;
1167                         return 0;
1168                 }
1169                 if (rc == -ERESTARTSYS && freezing(current)) {
1170                         clear_thread_flag(TIF_SIGPENDING);
1171                         goto again;
1172                 }
1173         } else {
1174                 do {
1175                         msleep(TPM_TIMEOUT);
1176                         status = chip->vendor.status(chip);
1177                         if ((status & mask) == mask)
1178                                 return 0;
1179                 } while (time_before(jiffies, stop));
1180         }
1181         return -ETIME;
1182 }
1183 EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
1184 /*
1185  * Device file system interface to the TPM
1186  *
1187  * It's assured that the chip will be opened just once,
1188  * by the check of is_open variable, which is protected
1189  * by driver_lock.
1190  */
1191 int tpm_open(struct inode *inode, struct file *file)
1192 {
1193         int minor = iminor(inode);
1194         struct tpm_chip *chip = NULL, *pos;
1195
1196         rcu_read_lock();
1197         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
1198                 if (pos->vendor.miscdev.minor == minor) {
1199                         chip = pos;
1200                         get_device(chip->dev);
1201                         break;
1202                 }
1203         }
1204         rcu_read_unlock();
1205
1206         if (!chip)
1207                 return -ENODEV;
1208
1209         if (test_and_set_bit(0, &chip->is_open)) {
1210                 dev_dbg(chip->dev, "Another process owns this TPM\n");
1211                 put_device(chip->dev);
1212                 return -EBUSY;
1213         }
1214
1215         chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
1216         if (chip->data_buffer == NULL) {
1217                 clear_bit(0, &chip->is_open);
1218                 put_device(chip->dev);
1219                 return -ENOMEM;
1220         }
1221
1222         atomic_set(&chip->data_pending, 0);
1223
1224         file->private_data = chip;
1225         return 0;
1226 }
1227 EXPORT_SYMBOL_GPL(tpm_open);
1228
1229 /*
1230  * Called on file close
1231  */
1232 int tpm_release(struct inode *inode, struct file *file)
1233 {
1234         struct tpm_chip *chip = file->private_data;
1235
1236         del_singleshot_timer_sync(&chip->user_read_timer);
1237         flush_work(&chip->work);
1238         file->private_data = NULL;
1239         atomic_set(&chip->data_pending, 0);
1240         kzfree(chip->data_buffer);
1241         clear_bit(0, &chip->is_open);
1242         put_device(chip->dev);
1243         return 0;
1244 }
1245 EXPORT_SYMBOL_GPL(tpm_release);
1246
1247 ssize_t tpm_write(struct file *file, const char __user *buf,
1248                   size_t size, loff_t *off)
1249 {
1250         struct tpm_chip *chip = file->private_data;
1251         size_t in_size = size;
1252         ssize_t out_size;
1253
1254         /* cannot perform a write until the read has cleared
1255            either via tpm_read or a user_read_timer timeout.
1256            This also prevents splitted buffered writes from blocking here.
1257         */
1258         if (atomic_read(&chip->data_pending) != 0)
1259                 return -EBUSY;
1260
1261         if (in_size > TPM_BUFSIZE)
1262                 return -E2BIG;
1263
1264         mutex_lock(&chip->buffer_mutex);
1265
1266         if (copy_from_user
1267             (chip->data_buffer, (void __user *) buf, in_size)) {
1268                 mutex_unlock(&chip->buffer_mutex);
1269                 return -EFAULT;
1270         }
1271
1272         /* atomic tpm command send and result receive */
1273         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1274         if (out_size < 0) {
1275                 mutex_unlock(&chip->buffer_mutex);
1276                 return out_size;
1277         }
1278
1279         atomic_set(&chip->data_pending, out_size);
1280         mutex_unlock(&chip->buffer_mutex);
1281
1282         /* Set a timeout by which the reader must come claim the result */
1283         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1284
1285         return in_size;
1286 }
1287 EXPORT_SYMBOL_GPL(tpm_write);
1288
1289 ssize_t tpm_read(struct file *file, char __user *buf,
1290                  size_t size, loff_t *off)
1291 {
1292         struct tpm_chip *chip = file->private_data;
1293         ssize_t ret_size;
1294         int rc;
1295
1296         del_singleshot_timer_sync(&chip->user_read_timer);
1297         flush_work(&chip->work);
1298         ret_size = atomic_read(&chip->data_pending);
1299         if (ret_size > 0) {     /* relay data */
1300                 ssize_t orig_ret_size = ret_size;
1301                 if (size < ret_size)
1302                         ret_size = size;
1303
1304                 mutex_lock(&chip->buffer_mutex);
1305                 rc = copy_to_user(buf, chip->data_buffer, ret_size);
1306                 memset(chip->data_buffer, 0, orig_ret_size);
1307                 if (rc)
1308                         ret_size = -EFAULT;
1309
1310                 mutex_unlock(&chip->buffer_mutex);
1311         }
1312
1313         atomic_set(&chip->data_pending, 0);
1314
1315         return ret_size;
1316 }
1317 EXPORT_SYMBOL_GPL(tpm_read);
1318
1319 void tpm_remove_hardware(struct device *dev)
1320 {
1321         struct tpm_chip *chip = dev_get_drvdata(dev);
1322
1323         if (chip == NULL) {
1324                 dev_err(dev, "No device data found\n");
1325                 return;
1326         }
1327
1328         spin_lock(&driver_lock);
1329         list_del_rcu(&chip->list);
1330         spin_unlock(&driver_lock);
1331         synchronize_rcu();
1332
1333         misc_deregister(&chip->vendor.miscdev);
1334         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1335         tpm_remove_ppi(&dev->kobj);
1336         tpm_bios_log_teardown(chip->bios_dir);
1337
1338         /* write it this way to be explicit (chip->dev == dev) */
1339         put_device(chip->dev);
1340 }
1341 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1342
1343 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1344 #define SAVESTATE_RESULT_SIZE 10
1345
1346 static struct tpm_input_header savestate_header = {
1347         .tag = TPM_TAG_RQU_COMMAND,
1348         .length = cpu_to_be32(10),
1349         .ordinal = TPM_ORD_SAVESTATE
1350 };
1351
1352 /*
1353  * We are about to suspend. Save the TPM state
1354  * so that it can be restored.
1355  */
1356 int tpm_pm_suspend(struct device *dev)
1357 {
1358         struct tpm_chip *chip = dev_get_drvdata(dev);
1359         struct tpm_cmd_t cmd;
1360         int rc, try;
1361
1362         u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1363
1364         if (chip == NULL)
1365                 return -ENODEV;
1366
1367         /* for buggy tpm, flush pcrs with extend to selected dummy */
1368         if (tpm_suspend_pcr) {
1369                 cmd.header.in = pcrextend_header;
1370                 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1371                 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1372                        TPM_DIGEST_SIZE);
1373                 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1374                                   "extending dummy pcr before suspend");
1375         }
1376
1377         /* now do the actual savestate */
1378         for (try = 0; try < TPM_RETRY; try++) {
1379                 cmd.header.in = savestate_header;
1380                 rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, NULL);
1381
1382                 /*
1383                  * If the TPM indicates that it is too busy to respond to
1384                  * this command then retry before giving up.  It can take
1385                  * several seconds for this TPM to be ready.
1386                  *
1387                  * This can happen if the TPM has already been sent the
1388                  * SaveState command before the driver has loaded.  TCG 1.2
1389                  * specification states that any communication after SaveState
1390                  * may cause the TPM to invalidate previously saved state.
1391                  */
1392                 if (rc != TPM_WARN_RETRY)
1393                         break;
1394                 msleep(TPM_TIMEOUT_RETRY);
1395         }
1396
1397         if (rc)
1398                 dev_err(chip->dev,
1399                         "Error (%d) sending savestate before suspend\n", rc);
1400         else if (try > 0)
1401                 dev_warn(chip->dev, "TPM savestate took %dms\n",
1402                          try * TPM_TIMEOUT_RETRY);
1403
1404         return rc;
1405 }
1406 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1407
1408 /*
1409  * Resume from a power safe. The BIOS already restored
1410  * the TPM state.
1411  */
1412 int tpm_pm_resume(struct device *dev)
1413 {
1414         struct tpm_chip *chip = dev_get_drvdata(dev);
1415
1416         if (chip == NULL)
1417                 return -ENODEV;
1418
1419         return 0;
1420 }
1421 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1422
1423 #define TPM_GETRANDOM_RESULT_SIZE       18
1424 static struct tpm_input_header tpm_getrandom_header = {
1425         .tag = TPM_TAG_RQU_COMMAND,
1426         .length = cpu_to_be32(14),
1427         .ordinal = TPM_ORD_GET_RANDOM
1428 };
1429
1430 /**
1431  * tpm_get_random() - Get random bytes from the tpm's RNG
1432  * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1433  * @out: destination buffer for the random bytes
1434  * @max: the max number of bytes to write to @out
1435  *
1436  * Returns < 0 on error and the number of bytes read on success
1437  */
1438 int tpm_get_random(u32 chip_num, u8 *out, size_t max)
1439 {
1440         struct tpm_chip *chip;
1441         struct tpm_cmd_t tpm_cmd;
1442         u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA);
1443         int err, total = 0, retries = 5;
1444         u8 *dest = out;
1445
1446         if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
1447                 return -EINVAL;
1448
1449         chip = tpm_chip_find_get(chip_num);
1450         if (chip == NULL)
1451                 return -ENODEV;
1452
1453         do {
1454                 tpm_cmd.header.in = tpm_getrandom_header;
1455                 tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
1456
1457                 err = transmit_cmd(chip, &tpm_cmd,
1458                                    TPM_GETRANDOM_RESULT_SIZE + num_bytes,
1459                                    "attempting get random");
1460                 if (err)
1461                         break;
1462
1463                 recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
1464                 memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
1465
1466                 dest += recd;
1467                 total += recd;
1468                 num_bytes -= recd;
1469         } while (retries-- && total < max);
1470
1471         tpm_chip_put(chip);
1472         return total ? total : -EIO;
1473 }
1474 EXPORT_SYMBOL_GPL(tpm_get_random);
1475
1476 /* In case vendor provided release function, call it too.*/
1477
1478 void tpm_dev_vendor_release(struct tpm_chip *chip)
1479 {
1480         if (!chip)
1481                 return;
1482
1483         if (chip->vendor.release)
1484                 chip->vendor.release(chip->dev);
1485
1486         clear_bit(chip->dev_num, dev_mask);
1487         kfree(chip->vendor.miscdev.name);
1488 }
1489 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1490
1491
1492 /*
1493  * Once all references to platform device are down to 0,
1494  * release all allocated structures.
1495  */
1496 static void tpm_dev_release(struct device *dev)
1497 {
1498         struct tpm_chip *chip = dev_get_drvdata(dev);
1499
1500         if (!chip)
1501                 return;
1502
1503         tpm_dev_vendor_release(chip);
1504
1505         chip->release(dev);
1506         kfree(chip);
1507 }
1508 EXPORT_SYMBOL_GPL(tpm_dev_release);
1509
1510 /*
1511  * Called from tpm_<specific>.c probe function only for devices
1512  * the driver has determined it should claim.  Prior to calling
1513  * this function the specific probe function has called pci_enable_device
1514  * upon errant exit from this function specific probe function should call
1515  * pci_disable_device
1516  */
1517 struct tpm_chip *tpm_register_hardware(struct device *dev,
1518                                         const struct tpm_vendor_specific *entry)
1519 {
1520 #define DEVNAME_SIZE 7
1521
1522         char *devname;
1523         struct tpm_chip *chip;
1524
1525         /* Driver specific per-device data */
1526         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1527         devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1528
1529         if (chip == NULL || devname == NULL)
1530                 goto out_free;
1531
1532         mutex_init(&chip->buffer_mutex);
1533         mutex_init(&chip->tpm_mutex);
1534         INIT_LIST_HEAD(&chip->list);
1535
1536         INIT_WORK(&chip->work, timeout_work);
1537
1538         setup_timer(&chip->user_read_timer, user_reader_timeout,
1539                         (unsigned long)chip);
1540
1541         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1542
1543         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1544
1545         if (chip->dev_num >= TPM_NUM_DEVICES) {
1546                 dev_err(dev, "No available tpm device numbers\n");
1547                 goto out_free;
1548         } else if (chip->dev_num == 0)
1549                 chip->vendor.miscdev.minor = TPM_MINOR;
1550         else
1551                 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1552
1553         set_bit(chip->dev_num, dev_mask);
1554
1555         scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1556         chip->vendor.miscdev.name = devname;
1557
1558         chip->vendor.miscdev.parent = dev;
1559         chip->dev = get_device(dev);
1560         chip->release = dev->release;
1561         dev->release = tpm_dev_release;
1562         dev_set_drvdata(dev, chip);
1563
1564         if (misc_register(&chip->vendor.miscdev)) {
1565                 dev_err(chip->dev,
1566                         "unable to misc_register %s, minor %d\n",
1567                         chip->vendor.miscdev.name,
1568                         chip->vendor.miscdev.minor);
1569                 goto put_device;
1570         }
1571
1572         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1573                 misc_deregister(&chip->vendor.miscdev);
1574                 goto put_device;
1575         }
1576
1577         if (tpm_add_ppi(&dev->kobj)) {
1578                 misc_deregister(&chip->vendor.miscdev);
1579                 goto put_device;
1580         }
1581
1582         chip->bios_dir = tpm_bios_log_setup(devname);
1583
1584         /* Make chip available */
1585         spin_lock(&driver_lock);
1586         list_add_rcu(&chip->list, &tpm_chip_list);
1587         spin_unlock(&driver_lock);
1588
1589         return chip;
1590
1591 put_device:
1592         put_device(chip->dev);
1593 out_free:
1594         kfree(chip);
1595         kfree(devname);
1596         return NULL;
1597 }
1598 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1599
1600 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1601 MODULE_DESCRIPTION("TPM Driver");
1602 MODULE_VERSION("2.0");
1603 MODULE_LICENSE("GPL");