1 /* 2 * Copyright (C) 2004 IBM Corporation 3 * Copyright (C) 2014 Intel Corporation 4 * 5 * Authors: 6 * Leendert van Doorn <leendert@watson.ibm.com> 7 * Dave Safford <safford@watson.ibm.com> 8 * Reiner Sailer <sailer@watson.ibm.com> 9 * Kylene Hall <kjhall@us.ibm.com> 10 * 11 * Maintained by: <tpmdd-devel@lists.sourceforge.net> 12 * 13 * Device driver for TCG/TCPA TPM (trusted platform module). 14 * Specifications at www.trustedcomputinggroup.org 15 * 16 * This program is free software; you can redistribute it and/or 17 * modify it under the terms of the GNU General Public License as 18 * published by the Free Software Foundation, version 2 of the 19 * License. 20 * 21 * Note, the TPM chip is not interrupt driven (only polling) 22 * and can have very long timeouts (minutes!). Hence the unusual 23 * calls to msleep. 24 * 25 */ 26 27 #include <linux/poll.h> 28 #include <linux/slab.h> 29 #include <linux/mutex.h> 30 #include <linux/spinlock.h> 31 #include <linux/freezer.h> 32 #include <linux/pm_runtime.h> 33 34 #include "tpm.h" 35 #include "tpm_eventlog.h" 36 37 #define TPM_MAX_ORDINAL 243 38 #define TSC_MAX_ORDINAL 12 39 #define TPM_PROTECTED_COMMAND 0x00 40 #define TPM_CONNECTION_COMMAND 0x40 41 42 /* 43 * Bug workaround - some TPM's don't flush the most 44 * recently changed pcr on suspend, so force the flush 45 * with an extend to the selected _unused_ non-volatile pcr. 46 */ 47 static int tpm_suspend_pcr; 48 module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644); 49 MODULE_PARM_DESC(suspend_pcr, 50 "PCR to use for dummy writes to facilitate flush on suspend."); 51 52 /* 53 * Array with one entry per ordinal defining the maximum amount 54 * of time the chip could take to return the result. The ordinal 55 * designation of short, medium or long is defined in a table in 56 * TCG Specification TPM Main Part 2 TPM Structures Section 17. The 57 * values of the SHORT, MEDIUM, and LONG durations are retrieved 58 * from the chip during initialization with a call to tpm_get_timeouts. 59 */ 60 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = { 61 TPM_UNDEFINED, /* 0 */ 62 TPM_UNDEFINED, 63 TPM_UNDEFINED, 64 TPM_UNDEFINED, 65 TPM_UNDEFINED, 66 TPM_UNDEFINED, /* 5 */ 67 TPM_UNDEFINED, 68 TPM_UNDEFINED, 69 TPM_UNDEFINED, 70 TPM_UNDEFINED, 71 TPM_SHORT, /* 10 */ 72 TPM_SHORT, 73 TPM_MEDIUM, 74 TPM_LONG, 75 TPM_LONG, 76 TPM_MEDIUM, /* 15 */ 77 TPM_SHORT, 78 TPM_SHORT, 79 TPM_MEDIUM, 80 TPM_LONG, 81 TPM_SHORT, /* 20 */ 82 TPM_SHORT, 83 TPM_MEDIUM, 84 TPM_MEDIUM, 85 TPM_MEDIUM, 86 TPM_SHORT, /* 25 */ 87 TPM_SHORT, 88 TPM_MEDIUM, 89 TPM_SHORT, 90 TPM_SHORT, 91 TPM_MEDIUM, /* 30 */ 92 TPM_LONG, 93 TPM_MEDIUM, 94 TPM_SHORT, 95 TPM_SHORT, 96 TPM_SHORT, /* 35 */ 97 TPM_MEDIUM, 98 TPM_MEDIUM, 99 TPM_UNDEFINED, 100 TPM_UNDEFINED, 101 TPM_MEDIUM, /* 40 */ 102 TPM_LONG, 103 TPM_MEDIUM, 104 TPM_SHORT, 105 TPM_SHORT, 106 TPM_SHORT, /* 45 */ 107 TPM_SHORT, 108 TPM_SHORT, 109 TPM_SHORT, 110 TPM_LONG, 111 TPM_MEDIUM, /* 50 */ 112 TPM_MEDIUM, 113 TPM_UNDEFINED, 114 TPM_UNDEFINED, 115 TPM_UNDEFINED, 116 TPM_UNDEFINED, /* 55 */ 117 TPM_UNDEFINED, 118 TPM_UNDEFINED, 119 TPM_UNDEFINED, 120 TPM_UNDEFINED, 121 TPM_MEDIUM, /* 60 */ 122 TPM_MEDIUM, 123 TPM_MEDIUM, 124 TPM_SHORT, 125 TPM_SHORT, 126 TPM_MEDIUM, /* 65 */ 127 TPM_UNDEFINED, 128 TPM_UNDEFINED, 129 TPM_UNDEFINED, 130 TPM_UNDEFINED, 131 TPM_SHORT, /* 70 */ 132 TPM_SHORT, 133 TPM_UNDEFINED, 134 TPM_UNDEFINED, 135 TPM_UNDEFINED, 136 TPM_UNDEFINED, /* 75 */ 137 TPM_UNDEFINED, 138 TPM_UNDEFINED, 139 TPM_UNDEFINED, 140 TPM_UNDEFINED, 141 TPM_LONG, /* 80 */ 142 TPM_UNDEFINED, 143 TPM_MEDIUM, 144 TPM_LONG, 145 TPM_SHORT, 146 TPM_UNDEFINED, /* 85 */ 147 TPM_UNDEFINED, 148 TPM_UNDEFINED, 149 TPM_UNDEFINED, 150 TPM_UNDEFINED, 151 TPM_SHORT, /* 90 */ 152 TPM_SHORT, 153 TPM_SHORT, 154 TPM_SHORT, 155 TPM_SHORT, 156 TPM_UNDEFINED, /* 95 */ 157 TPM_UNDEFINED, 158 TPM_UNDEFINED, 159 TPM_UNDEFINED, 160 TPM_UNDEFINED, 161 TPM_MEDIUM, /* 100 */ 162 TPM_SHORT, 163 TPM_SHORT, 164 TPM_UNDEFINED, 165 TPM_UNDEFINED, 166 TPM_UNDEFINED, /* 105 */ 167 TPM_UNDEFINED, 168 TPM_UNDEFINED, 169 TPM_UNDEFINED, 170 TPM_UNDEFINED, 171 TPM_SHORT, /* 110 */ 172 TPM_SHORT, 173 TPM_SHORT, 174 TPM_SHORT, 175 TPM_SHORT, 176 TPM_SHORT, /* 115 */ 177 TPM_SHORT, 178 TPM_SHORT, 179 TPM_UNDEFINED, 180 TPM_UNDEFINED, 181 TPM_LONG, /* 120 */ 182 TPM_LONG, 183 TPM_MEDIUM, 184 TPM_UNDEFINED, 185 TPM_SHORT, 186 TPM_SHORT, /* 125 */ 187 TPM_SHORT, 188 TPM_LONG, 189 TPM_SHORT, 190 TPM_SHORT, 191 TPM_SHORT, /* 130 */ 192 TPM_MEDIUM, 193 TPM_UNDEFINED, 194 TPM_SHORT, 195 TPM_MEDIUM, 196 TPM_UNDEFINED, /* 135 */ 197 TPM_UNDEFINED, 198 TPM_UNDEFINED, 199 TPM_UNDEFINED, 200 TPM_UNDEFINED, 201 TPM_SHORT, /* 140 */ 202 TPM_SHORT, 203 TPM_UNDEFINED, 204 TPM_UNDEFINED, 205 TPM_UNDEFINED, 206 TPM_UNDEFINED, /* 145 */ 207 TPM_UNDEFINED, 208 TPM_UNDEFINED, 209 TPM_UNDEFINED, 210 TPM_UNDEFINED, 211 TPM_SHORT, /* 150 */ 212 TPM_MEDIUM, 213 TPM_MEDIUM, 214 TPM_SHORT, 215 TPM_SHORT, 216 TPM_UNDEFINED, /* 155 */ 217 TPM_UNDEFINED, 218 TPM_UNDEFINED, 219 TPM_UNDEFINED, 220 TPM_UNDEFINED, 221 TPM_SHORT, /* 160 */ 222 TPM_SHORT, 223 TPM_SHORT, 224 TPM_SHORT, 225 TPM_UNDEFINED, 226 TPM_UNDEFINED, /* 165 */ 227 TPM_UNDEFINED, 228 TPM_UNDEFINED, 229 TPM_UNDEFINED, 230 TPM_UNDEFINED, 231 TPM_LONG, /* 170 */ 232 TPM_UNDEFINED, 233 TPM_UNDEFINED, 234 TPM_UNDEFINED, 235 TPM_UNDEFINED, 236 TPM_UNDEFINED, /* 175 */ 237 TPM_UNDEFINED, 238 TPM_UNDEFINED, 239 TPM_UNDEFINED, 240 TPM_UNDEFINED, 241 TPM_MEDIUM, /* 180 */ 242 TPM_SHORT, 243 TPM_MEDIUM, 244 TPM_MEDIUM, 245 TPM_MEDIUM, 246 TPM_MEDIUM, /* 185 */ 247 TPM_SHORT, 248 TPM_UNDEFINED, 249 TPM_UNDEFINED, 250 TPM_UNDEFINED, 251 TPM_UNDEFINED, /* 190 */ 252 TPM_UNDEFINED, 253 TPM_UNDEFINED, 254 TPM_UNDEFINED, 255 TPM_UNDEFINED, 256 TPM_UNDEFINED, /* 195 */ 257 TPM_UNDEFINED, 258 TPM_UNDEFINED, 259 TPM_UNDEFINED, 260 TPM_UNDEFINED, 261 TPM_SHORT, /* 200 */ 262 TPM_UNDEFINED, 263 TPM_UNDEFINED, 264 TPM_UNDEFINED, 265 TPM_SHORT, 266 TPM_SHORT, /* 205 */ 267 TPM_SHORT, 268 TPM_SHORT, 269 TPM_SHORT, 270 TPM_SHORT, 271 TPM_MEDIUM, /* 210 */ 272 TPM_UNDEFINED, 273 TPM_MEDIUM, 274 TPM_MEDIUM, 275 TPM_MEDIUM, 276 TPM_UNDEFINED, /* 215 */ 277 TPM_MEDIUM, 278 TPM_UNDEFINED, 279 TPM_UNDEFINED, 280 TPM_SHORT, 281 TPM_SHORT, /* 220 */ 282 TPM_SHORT, 283 TPM_SHORT, 284 TPM_SHORT, 285 TPM_SHORT, 286 TPM_UNDEFINED, /* 225 */ 287 TPM_UNDEFINED, 288 TPM_UNDEFINED, 289 TPM_UNDEFINED, 290 TPM_UNDEFINED, 291 TPM_SHORT, /* 230 */ 292 TPM_LONG, 293 TPM_MEDIUM, 294 TPM_UNDEFINED, 295 TPM_UNDEFINED, 296 TPM_UNDEFINED, /* 235 */ 297 TPM_UNDEFINED, 298 TPM_UNDEFINED, 299 TPM_UNDEFINED, 300 TPM_UNDEFINED, 301 TPM_SHORT, /* 240 */ 302 TPM_UNDEFINED, 303 TPM_MEDIUM, 304 }; 305 306 /* 307 * Returns max number of jiffies to wait 308 */ 309 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip, 310 u32 ordinal) 311 { 312 int duration_idx = TPM_UNDEFINED; 313 int duration = 0; 314 315 /* 316 * We only have a duration table for protected commands, where the upper 317 * 16 bits are 0. For the few other ordinals the fallback will be used. 318 */ 319 if (ordinal < TPM_MAX_ORDINAL) 320 duration_idx = tpm_ordinal_duration[ordinal]; 321 322 if (duration_idx != TPM_UNDEFINED) 323 duration = chip->duration[duration_idx]; 324 if (duration <= 0) 325 return 2 * 60 * HZ; 326 else 327 return duration; 328 } 329 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration); 330 331 /** 332 * tmp_transmit - Internal kernel interface to transmit TPM commands. 333 * 334 * @chip: TPM chip to use 335 * @buf: TPM command buffer 336 * @bufsiz: length of the TPM command buffer 337 * @flags: tpm transmit flags - bitmap 338 * 339 * Return: 340 * 0 when the operation is successful. 341 * A negative number for system errors (errno). 342 */ 343 ssize_t tpm_transmit(struct tpm_chip *chip, const u8 *buf, size_t bufsiz, 344 unsigned int flags) 345 { 346 const struct tpm_output_header *header = (void *)buf; 347 ssize_t rc; 348 u32 count, ordinal; 349 unsigned long stop; 350 351 if (bufsiz < TPM_HEADER_SIZE) 352 return -EINVAL; 353 354 if (bufsiz > TPM_BUFSIZE) 355 bufsiz = TPM_BUFSIZE; 356 357 count = be32_to_cpu(*((__be32 *) (buf + 2))); 358 ordinal = be32_to_cpu(*((__be32 *) (buf + 6))); 359 if (count == 0) 360 return -ENODATA; 361 if (count > bufsiz) { 362 dev_err(&chip->dev, 363 "invalid count value %x %zx\n", count, bufsiz); 364 return -E2BIG; 365 } 366 367 if (!(flags & TPM_TRANSMIT_UNLOCKED)) 368 mutex_lock(&chip->tpm_mutex); 369 370 if (chip->dev.parent) 371 pm_runtime_get_sync(chip->dev.parent); 372 373 rc = chip->ops->send(chip, (u8 *) buf, count); 374 if (rc < 0) { 375 dev_err(&chip->dev, 376 "tpm_transmit: tpm_send: error %zd\n", rc); 377 goto out; 378 } 379 380 if (chip->flags & TPM_CHIP_FLAG_IRQ) 381 goto out_recv; 382 383 if (chip->flags & TPM_CHIP_FLAG_TPM2) 384 stop = jiffies + tpm2_calc_ordinal_duration(chip, ordinal); 385 else 386 stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal); 387 do { 388 u8 status = chip->ops->status(chip); 389 if ((status & chip->ops->req_complete_mask) == 390 chip->ops->req_complete_val) 391 goto out_recv; 392 393 if (chip->ops->req_canceled(chip, status)) { 394 dev_err(&chip->dev, "Operation Canceled\n"); 395 rc = -ECANCELED; 396 goto out; 397 } 398 399 msleep(TPM_TIMEOUT); /* CHECK */ 400 rmb(); 401 } while (time_before(jiffies, stop)); 402 403 chip->ops->cancel(chip); 404 dev_err(&chip->dev, "Operation Timed out\n"); 405 rc = -ETIME; 406 goto out; 407 408 out_recv: 409 rc = chip->ops->recv(chip, (u8 *) buf, bufsiz); 410 if (rc < 0) { 411 dev_err(&chip->dev, 412 "tpm_transmit: tpm_recv: error %zd\n", rc); 413 goto out; 414 } else if (rc < TPM_HEADER_SIZE) { 415 rc = -EFAULT; 416 goto out; 417 } 418 419 if (rc != be32_to_cpu(header->length)) 420 goto out; 421 422 out: 423 if (chip->dev.parent) 424 pm_runtime_put_sync(chip->dev.parent); 425 426 if (!(flags & TPM_TRANSMIT_UNLOCKED)) 427 mutex_unlock(&chip->tpm_mutex); 428 return rc; 429 } 430 431 /** 432 * tmp_transmit_cmd - send a tpm command to the device 433 * The function extracts tpm out header return code 434 * 435 * @chip: TPM chip to use 436 * @buf: TPM command buffer 437 * @bufsiz: length of the buffer 438 * @min_rsp_body_length: minimum expected length of response body 439 * @flags: tpm transmit flags - bitmap 440 * @desc: command description used in the error message 441 * 442 * Return: 443 * 0 when the operation is successful. 444 * A negative number for system errors (errno). 445 * A positive number for a TPM error. 446 */ 447 ssize_t tpm_transmit_cmd(struct tpm_chip *chip, const void *buf, 448 size_t bufsiz, size_t min_rsp_body_length, 449 unsigned int flags, const char *desc) 450 { 451 const struct tpm_output_header *header = buf; 452 int err; 453 ssize_t len; 454 455 len = tpm_transmit(chip, (const u8 *)buf, bufsiz, flags); 456 if (len < 0) 457 return len; 458 459 err = be32_to_cpu(header->return_code); 460 if (err != 0 && desc) 461 dev_err(&chip->dev, "A TPM error (%d) occurred %s\n", err, 462 desc); 463 if (err) 464 return err; 465 466 if (len < min_rsp_body_length + TPM_HEADER_SIZE) 467 return -EFAULT; 468 469 return 0; 470 } 471 472 #define TPM_DIGEST_SIZE 20 473 #define TPM_RET_CODE_IDX 6 474 #define TPM_INTERNAL_RESULT_SIZE 200 475 #define TPM_ORD_GET_CAP cpu_to_be32(101) 476 #define TPM_ORD_GET_RANDOM cpu_to_be32(70) 477 478 static const struct tpm_input_header tpm_getcap_header = { 479 .tag = TPM_TAG_RQU_COMMAND, 480 .length = cpu_to_be32(22), 481 .ordinal = TPM_ORD_GET_CAP 482 }; 483 484 ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap, 485 const char *desc, size_t min_cap_length) 486 { 487 struct tpm_cmd_t tpm_cmd; 488 int rc; 489 490 tpm_cmd.header.in = tpm_getcap_header; 491 if (subcap_id == TPM_CAP_VERSION_1_1 || 492 subcap_id == TPM_CAP_VERSION_1_2) { 493 tpm_cmd.params.getcap_in.cap = cpu_to_be32(subcap_id); 494 /*subcap field not necessary */ 495 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0); 496 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32)); 497 } else { 498 if (subcap_id == TPM_CAP_FLAG_PERM || 499 subcap_id == TPM_CAP_FLAG_VOL) 500 tpm_cmd.params.getcap_in.cap = 501 cpu_to_be32(TPM_CAP_FLAG); 502 else 503 tpm_cmd.params.getcap_in.cap = 504 cpu_to_be32(TPM_CAP_PROP); 505 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4); 506 tpm_cmd.params.getcap_in.subcap = cpu_to_be32(subcap_id); 507 } 508 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 509 min_cap_length, 0, desc); 510 if (!rc) 511 *cap = tpm_cmd.params.getcap_out.cap; 512 return rc; 513 } 514 EXPORT_SYMBOL_GPL(tpm_getcap); 515 516 #define TPM_ORD_STARTUP cpu_to_be32(153) 517 #define TPM_ST_CLEAR cpu_to_be16(1) 518 #define TPM_ST_STATE cpu_to_be16(2) 519 #define TPM_ST_DEACTIVATED cpu_to_be16(3) 520 static const struct tpm_input_header tpm_startup_header = { 521 .tag = TPM_TAG_RQU_COMMAND, 522 .length = cpu_to_be32(12), 523 .ordinal = TPM_ORD_STARTUP 524 }; 525 526 static int tpm_startup(struct tpm_chip *chip, __be16 startup_type) 527 { 528 struct tpm_cmd_t start_cmd; 529 start_cmd.header.in = tpm_startup_header; 530 531 start_cmd.params.startup_in.startup_type = startup_type; 532 return tpm_transmit_cmd(chip, &start_cmd, TPM_INTERNAL_RESULT_SIZE, 0, 533 0, "attempting to start the TPM"); 534 } 535 536 int tpm_get_timeouts(struct tpm_chip *chip) 537 { 538 cap_t cap; 539 unsigned long timeout_old[4], timeout_chip[4], timeout_eff[4]; 540 ssize_t rc; 541 542 if (chip->flags & TPM_CHIP_FLAG_HAVE_TIMEOUTS) 543 return 0; 544 545 if (chip->flags & TPM_CHIP_FLAG_TPM2) { 546 /* Fixed timeouts for TPM2 */ 547 chip->timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A); 548 chip->timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B); 549 chip->timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C); 550 chip->timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D); 551 chip->duration[TPM_SHORT] = 552 msecs_to_jiffies(TPM2_DURATION_SHORT); 553 chip->duration[TPM_MEDIUM] = 554 msecs_to_jiffies(TPM2_DURATION_MEDIUM); 555 chip->duration[TPM_LONG] = 556 msecs_to_jiffies(TPM2_DURATION_LONG); 557 558 chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS; 559 return 0; 560 } 561 562 rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, NULL, 563 sizeof(cap.timeout)); 564 if (rc == TPM_ERR_INVALID_POSTINIT) { 565 /* The TPM is not started, we are the first to talk to it. 566 Execute a startup command. */ 567 dev_info(&chip->dev, "Issuing TPM_STARTUP\n"); 568 if (tpm_startup(chip, TPM_ST_CLEAR)) 569 return rc; 570 571 rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, 572 "attempting to determine the timeouts", 573 sizeof(cap.timeout)); 574 } 575 576 if (rc) { 577 dev_err(&chip->dev, 578 "A TPM error (%zd) occurred attempting to determine the timeouts\n", 579 rc); 580 return rc; 581 } 582 583 timeout_old[0] = jiffies_to_usecs(chip->timeout_a); 584 timeout_old[1] = jiffies_to_usecs(chip->timeout_b); 585 timeout_old[2] = jiffies_to_usecs(chip->timeout_c); 586 timeout_old[3] = jiffies_to_usecs(chip->timeout_d); 587 timeout_chip[0] = be32_to_cpu(cap.timeout.a); 588 timeout_chip[1] = be32_to_cpu(cap.timeout.b); 589 timeout_chip[2] = be32_to_cpu(cap.timeout.c); 590 timeout_chip[3] = be32_to_cpu(cap.timeout.d); 591 memcpy(timeout_eff, timeout_chip, sizeof(timeout_eff)); 592 593 /* 594 * Provide ability for vendor overrides of timeout values in case 595 * of misreporting. 596 */ 597 if (chip->ops->update_timeouts != NULL) 598 chip->timeout_adjusted = 599 chip->ops->update_timeouts(chip, timeout_eff); 600 601 if (!chip->timeout_adjusted) { 602 /* Restore default if chip reported 0 */ 603 int i; 604 605 for (i = 0; i < ARRAY_SIZE(timeout_eff); i++) { 606 if (timeout_eff[i]) 607 continue; 608 609 timeout_eff[i] = timeout_old[i]; 610 chip->timeout_adjusted = true; 611 } 612 613 if (timeout_eff[0] != 0 && timeout_eff[0] < 1000) { 614 /* timeouts in msec rather usec */ 615 for (i = 0; i != ARRAY_SIZE(timeout_eff); i++) 616 timeout_eff[i] *= 1000; 617 chip->timeout_adjusted = true; 618 } 619 } 620 621 /* Report adjusted timeouts */ 622 if (chip->timeout_adjusted) { 623 dev_info(&chip->dev, 624 HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n", 625 timeout_chip[0], timeout_eff[0], 626 timeout_chip[1], timeout_eff[1], 627 timeout_chip[2], timeout_eff[2], 628 timeout_chip[3], timeout_eff[3]); 629 } 630 631 chip->timeout_a = usecs_to_jiffies(timeout_eff[0]); 632 chip->timeout_b = usecs_to_jiffies(timeout_eff[1]); 633 chip->timeout_c = usecs_to_jiffies(timeout_eff[2]); 634 chip->timeout_d = usecs_to_jiffies(timeout_eff[3]); 635 636 rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap, 637 "attempting to determine the durations", 638 sizeof(cap.duration)); 639 if (rc) 640 return rc; 641 642 chip->duration[TPM_SHORT] = 643 usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short)); 644 chip->duration[TPM_MEDIUM] = 645 usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium)); 646 chip->duration[TPM_LONG] = 647 usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long)); 648 649 /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above 650 * value wrong and apparently reports msecs rather than usecs. So we 651 * fix up the resulting too-small TPM_SHORT value to make things work. 652 * We also scale the TPM_MEDIUM and -_LONG values by 1000. 653 */ 654 if (chip->duration[TPM_SHORT] < (HZ / 100)) { 655 chip->duration[TPM_SHORT] = HZ; 656 chip->duration[TPM_MEDIUM] *= 1000; 657 chip->duration[TPM_LONG] *= 1000; 658 chip->duration_adjusted = true; 659 dev_info(&chip->dev, "Adjusting TPM timeout parameters."); 660 } 661 662 chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS; 663 return 0; 664 } 665 EXPORT_SYMBOL_GPL(tpm_get_timeouts); 666 667 #define TPM_ORD_CONTINUE_SELFTEST 83 668 #define CONTINUE_SELFTEST_RESULT_SIZE 10 669 670 static const struct tpm_input_header continue_selftest_header = { 671 .tag = TPM_TAG_RQU_COMMAND, 672 .length = cpu_to_be32(10), 673 .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST), 674 }; 675 676 /** 677 * tpm_continue_selftest -- run TPM's selftest 678 * @chip: TPM chip to use 679 * 680 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing 681 * a TPM error code. 682 */ 683 static int tpm_continue_selftest(struct tpm_chip *chip) 684 { 685 int rc; 686 struct tpm_cmd_t cmd; 687 688 cmd.header.in = continue_selftest_header; 689 rc = tpm_transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE, 0, 0, 690 "continue selftest"); 691 return rc; 692 } 693 694 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21) 695 #define READ_PCR_RESULT_SIZE 30 696 #define READ_PCR_RESULT_BODY_SIZE 20 697 static const struct tpm_input_header pcrread_header = { 698 .tag = TPM_TAG_RQU_COMMAND, 699 .length = cpu_to_be32(14), 700 .ordinal = TPM_ORDINAL_PCRREAD 701 }; 702 703 int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) 704 { 705 int rc; 706 struct tpm_cmd_t cmd; 707 708 cmd.header.in = pcrread_header; 709 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx); 710 rc = tpm_transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE, 711 READ_PCR_RESULT_BODY_SIZE, 0, 712 "attempting to read a pcr value"); 713 714 if (rc == 0) 715 memcpy(res_buf, cmd.params.pcrread_out.pcr_result, 716 TPM_DIGEST_SIZE); 717 return rc; 718 } 719 720 /** 721 * tpm_is_tpm2 - is the chip a TPM2 chip? 722 * @chip_num: tpm idx # or ANY 723 * 724 * Returns < 0 on error, and 1 or 0 on success depending whether the chip 725 * is a TPM2 chip. 726 */ 727 int tpm_is_tpm2(u32 chip_num) 728 { 729 struct tpm_chip *chip; 730 int rc; 731 732 chip = tpm_chip_find_get(chip_num); 733 if (chip == NULL) 734 return -ENODEV; 735 736 rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0; 737 738 tpm_put_ops(chip); 739 740 return rc; 741 } 742 EXPORT_SYMBOL_GPL(tpm_is_tpm2); 743 744 /** 745 * tpm_pcr_read - read a pcr value 746 * @chip_num: tpm idx # or ANY 747 * @pcr_idx: pcr idx to retrieve 748 * @res_buf: TPM_PCR value 749 * size of res_buf is 20 bytes (or NULL if you don't care) 750 * 751 * The TPM driver should be built-in, but for whatever reason it 752 * isn't, protect against the chip disappearing, by incrementing 753 * the module usage count. 754 */ 755 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf) 756 { 757 struct tpm_chip *chip; 758 int rc; 759 760 chip = tpm_chip_find_get(chip_num); 761 if (chip == NULL) 762 return -ENODEV; 763 if (chip->flags & TPM_CHIP_FLAG_TPM2) 764 rc = tpm2_pcr_read(chip, pcr_idx, res_buf); 765 else 766 rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf); 767 tpm_put_ops(chip); 768 return rc; 769 } 770 EXPORT_SYMBOL_GPL(tpm_pcr_read); 771 772 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20) 773 #define EXTEND_PCR_RESULT_SIZE 34 774 #define EXTEND_PCR_RESULT_BODY_SIZE 20 775 static const struct tpm_input_header pcrextend_header = { 776 .tag = TPM_TAG_RQU_COMMAND, 777 .length = cpu_to_be32(34), 778 .ordinal = TPM_ORD_PCR_EXTEND 779 }; 780 781 /** 782 * tpm_pcr_extend - extend pcr value with hash 783 * @chip_num: tpm idx # or AN& 784 * @pcr_idx: pcr idx to extend 785 * @hash: hash value used to extend pcr value 786 * 787 * The TPM driver should be built-in, but for whatever reason it 788 * isn't, protect against the chip disappearing, by incrementing 789 * the module usage count. 790 */ 791 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash) 792 { 793 struct tpm_cmd_t cmd; 794 int rc; 795 struct tpm_chip *chip; 796 struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)]; 797 u32 count = 0; 798 int i; 799 800 chip = tpm_chip_find_get(chip_num); 801 if (chip == NULL) 802 return -ENODEV; 803 804 if (chip->flags & TPM_CHIP_FLAG_TPM2) { 805 memset(digest_list, 0, sizeof(digest_list)); 806 807 for (i = 0; i < ARRAY_SIZE(chip->active_banks) && 808 chip->active_banks[i] != TPM2_ALG_ERROR; i++) { 809 digest_list[i].alg_id = chip->active_banks[i]; 810 memcpy(digest_list[i].digest, hash, TPM_DIGEST_SIZE); 811 count++; 812 } 813 814 rc = tpm2_pcr_extend(chip, pcr_idx, count, digest_list); 815 tpm_put_ops(chip); 816 return rc; 817 } 818 819 cmd.header.in = pcrextend_header; 820 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx); 821 memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE); 822 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE, 823 EXTEND_PCR_RESULT_BODY_SIZE, 0, 824 "attempting extend a PCR value"); 825 826 tpm_put_ops(chip); 827 return rc; 828 } 829 EXPORT_SYMBOL_GPL(tpm_pcr_extend); 830 831 /** 832 * tpm_do_selftest - have the TPM continue its selftest and wait until it 833 * can receive further commands 834 * @chip: TPM chip to use 835 * 836 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing 837 * a TPM error code. 838 */ 839 int tpm_do_selftest(struct tpm_chip *chip) 840 { 841 int rc; 842 unsigned int loops; 843 unsigned int delay_msec = 100; 844 unsigned long duration; 845 u8 dummy[TPM_DIGEST_SIZE]; 846 847 duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST); 848 849 loops = jiffies_to_msecs(duration) / delay_msec; 850 851 rc = tpm_continue_selftest(chip); 852 /* This may fail if there was no TPM driver during a suspend/resume 853 * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST) 854 */ 855 if (rc) 856 return rc; 857 858 do { 859 /* Attempt to read a PCR value */ 860 rc = tpm_pcr_read_dev(chip, 0, dummy); 861 862 /* Some buggy TPMs will not respond to tpm_tis_ready() for 863 * around 300ms while the self test is ongoing, keep trying 864 * until the self test duration expires. */ 865 if (rc == -ETIME) { 866 dev_info( 867 &chip->dev, HW_ERR 868 "TPM command timed out during continue self test"); 869 msleep(delay_msec); 870 continue; 871 } 872 873 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) { 874 dev_info(&chip->dev, 875 "TPM is disabled/deactivated (0x%X)\n", rc); 876 /* TPM is disabled and/or deactivated; driver can 877 * proceed and TPM does handle commands for 878 * suspend/resume correctly 879 */ 880 return 0; 881 } 882 if (rc != TPM_WARN_DOING_SELFTEST) 883 return rc; 884 msleep(delay_msec); 885 } while (--loops > 0); 886 887 return rc; 888 } 889 EXPORT_SYMBOL_GPL(tpm_do_selftest); 890 891 /** 892 * tpm1_auto_startup - Perform the standard automatic TPM initialization 893 * sequence 894 * @chip: TPM chip to use 895 * 896 * Returns 0 on success, < 0 in case of fatal error. 897 */ 898 int tpm1_auto_startup(struct tpm_chip *chip) 899 { 900 int rc; 901 902 rc = tpm_get_timeouts(chip); 903 if (rc) 904 goto out; 905 rc = tpm_do_selftest(chip); 906 if (rc) { 907 dev_err(&chip->dev, "TPM self test failed\n"); 908 goto out; 909 } 910 911 return rc; 912 out: 913 if (rc > 0) 914 rc = -ENODEV; 915 return rc; 916 } 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 = tpm_transmit_cmd(chip, cmd, buflen, 0, 0, "attempting tpm_cmd"); 928 929 tpm_put_ops(chip); 930 return rc; 931 } 932 EXPORT_SYMBOL_GPL(tpm_send); 933 934 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask, 935 bool check_cancel, bool *canceled) 936 { 937 u8 status = chip->ops->status(chip); 938 939 *canceled = false; 940 if ((status & mask) == mask) 941 return true; 942 if (check_cancel && chip->ops->req_canceled(chip, status)) { 943 *canceled = true; 944 return true; 945 } 946 return false; 947 } 948 949 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout, 950 wait_queue_head_t *queue, bool check_cancel) 951 { 952 unsigned long stop; 953 long rc; 954 u8 status; 955 bool canceled = false; 956 957 /* check current status */ 958 status = chip->ops->status(chip); 959 if ((status & mask) == mask) 960 return 0; 961 962 stop = jiffies + timeout; 963 964 if (chip->flags & TPM_CHIP_FLAG_IRQ) { 965 again: 966 timeout = stop - jiffies; 967 if ((long)timeout <= 0) 968 return -ETIME; 969 rc = wait_event_interruptible_timeout(*queue, 970 wait_for_tpm_stat_cond(chip, mask, check_cancel, 971 &canceled), 972 timeout); 973 if (rc > 0) { 974 if (canceled) 975 return -ECANCELED; 976 return 0; 977 } 978 if (rc == -ERESTARTSYS && freezing(current)) { 979 clear_thread_flag(TIF_SIGPENDING); 980 goto again; 981 } 982 } else { 983 do { 984 msleep(TPM_TIMEOUT); 985 status = chip->ops->status(chip); 986 if ((status & mask) == mask) 987 return 0; 988 } while (time_before(jiffies, stop)); 989 } 990 return -ETIME; 991 } 992 EXPORT_SYMBOL_GPL(wait_for_tpm_stat); 993 994 #define TPM_ORD_SAVESTATE cpu_to_be32(152) 995 #define SAVESTATE_RESULT_SIZE 10 996 997 static const struct tpm_input_header savestate_header = { 998 .tag = TPM_TAG_RQU_COMMAND, 999 .length = cpu_to_be32(10), 1000 .ordinal = TPM_ORD_SAVESTATE 1001 }; 1002 1003 /* 1004 * We are about to suspend. Save the TPM state 1005 * so that it can be restored. 1006 */ 1007 int tpm_pm_suspend(struct device *dev) 1008 { 1009 struct tpm_chip *chip = dev_get_drvdata(dev); 1010 struct tpm_cmd_t cmd; 1011 int rc, try; 1012 1013 u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 }; 1014 1015 if (chip == NULL) 1016 return -ENODEV; 1017 1018 if (chip->flags & TPM_CHIP_FLAG_TPM2) { 1019 tpm2_shutdown(chip, TPM2_SU_STATE); 1020 return 0; 1021 } 1022 1023 /* for buggy tpm, flush pcrs with extend to selected dummy */ 1024 if (tpm_suspend_pcr) { 1025 cmd.header.in = pcrextend_header; 1026 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr); 1027 memcpy(cmd.params.pcrextend_in.hash, dummy_hash, 1028 TPM_DIGEST_SIZE); 1029 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE, 1030 EXTEND_PCR_RESULT_BODY_SIZE, 0, 1031 "extending dummy pcr before suspend"); 1032 } 1033 1034 /* now do the actual savestate */ 1035 for (try = 0; try < TPM_RETRY; try++) { 1036 cmd.header.in = savestate_header; 1037 rc = tpm_transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, 0, 1038 0, NULL); 1039 1040 /* 1041 * If the TPM indicates that it is too busy to respond to 1042 * this command then retry before giving up. It can take 1043 * several seconds for this TPM to be ready. 1044 * 1045 * This can happen if the TPM has already been sent the 1046 * SaveState command before the driver has loaded. TCG 1.2 1047 * specification states that any communication after SaveState 1048 * may cause the TPM to invalidate previously saved state. 1049 */ 1050 if (rc != TPM_WARN_RETRY) 1051 break; 1052 msleep(TPM_TIMEOUT_RETRY); 1053 } 1054 1055 if (rc) 1056 dev_err(&chip->dev, 1057 "Error (%d) sending savestate before suspend\n", rc); 1058 else if (try > 0) 1059 dev_warn(&chip->dev, "TPM savestate took %dms\n", 1060 try * TPM_TIMEOUT_RETRY); 1061 1062 return rc; 1063 } 1064 EXPORT_SYMBOL_GPL(tpm_pm_suspend); 1065 1066 /* 1067 * Resume from a power safe. The BIOS already restored 1068 * the TPM state. 1069 */ 1070 int tpm_pm_resume(struct device *dev) 1071 { 1072 struct tpm_chip *chip = dev_get_drvdata(dev); 1073 1074 if (chip == NULL) 1075 return -ENODEV; 1076 1077 return 0; 1078 } 1079 EXPORT_SYMBOL_GPL(tpm_pm_resume); 1080 1081 #define TPM_GETRANDOM_RESULT_SIZE 18 1082 static const struct tpm_input_header tpm_getrandom_header = { 1083 .tag = TPM_TAG_RQU_COMMAND, 1084 .length = cpu_to_be32(14), 1085 .ordinal = TPM_ORD_GET_RANDOM 1086 }; 1087 1088 /** 1089 * tpm_get_random() - Get random bytes from the tpm's RNG 1090 * @chip_num: A specific chip number for the request or TPM_ANY_NUM 1091 * @out: destination buffer for the random bytes 1092 * @max: the max number of bytes to write to @out 1093 * 1094 * Returns < 0 on error and the number of bytes read on success 1095 */ 1096 int tpm_get_random(u32 chip_num, u8 *out, size_t max) 1097 { 1098 struct tpm_chip *chip; 1099 struct tpm_cmd_t tpm_cmd; 1100 u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA), rlength; 1101 int err, total = 0, retries = 5; 1102 u8 *dest = out; 1103 1104 if (!out || !num_bytes || max > TPM_MAX_RNG_DATA) 1105 return -EINVAL; 1106 1107 chip = tpm_chip_find_get(chip_num); 1108 if (chip == NULL) 1109 return -ENODEV; 1110 1111 if (chip->flags & TPM_CHIP_FLAG_TPM2) { 1112 err = tpm2_get_random(chip, out, max); 1113 tpm_put_ops(chip); 1114 return err; 1115 } 1116 1117 do { 1118 tpm_cmd.header.in = tpm_getrandom_header; 1119 tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes); 1120 1121 err = tpm_transmit_cmd(chip, &tpm_cmd, 1122 TPM_GETRANDOM_RESULT_SIZE + num_bytes, 1123 offsetof(struct tpm_getrandom_out, 1124 rng_data), 1125 0, "attempting get random"); 1126 if (err) 1127 break; 1128 1129 recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len); 1130 1131 rlength = be32_to_cpu(tpm_cmd.header.out.length); 1132 if (rlength < offsetof(struct tpm_getrandom_out, rng_data) + 1133 recd) { 1134 total = -EFAULT; 1135 break; 1136 } 1137 memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd); 1138 1139 dest += recd; 1140 total += recd; 1141 num_bytes -= recd; 1142 } while (retries-- && total < max); 1143 1144 tpm_put_ops(chip); 1145 return total ? total : -EIO; 1146 } 1147 EXPORT_SYMBOL_GPL(tpm_get_random); 1148 1149 /** 1150 * tpm_seal_trusted() - seal a trusted key 1151 * @chip_num: A specific chip number for the request or TPM_ANY_NUM 1152 * @options: authentication values and other options 1153 * @payload: the key data in clear and encrypted form 1154 * 1155 * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips 1156 * are supported. 1157 */ 1158 int tpm_seal_trusted(u32 chip_num, struct trusted_key_payload *payload, 1159 struct trusted_key_options *options) 1160 { 1161 struct tpm_chip *chip; 1162 int rc; 1163 1164 chip = tpm_chip_find_get(chip_num); 1165 if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2)) 1166 return -ENODEV; 1167 1168 rc = tpm2_seal_trusted(chip, payload, options); 1169 1170 tpm_put_ops(chip); 1171 return rc; 1172 } 1173 EXPORT_SYMBOL_GPL(tpm_seal_trusted); 1174 1175 /** 1176 * tpm_unseal_trusted() - unseal a trusted key 1177 * @chip_num: A specific chip number for the request or TPM_ANY_NUM 1178 * @options: authentication values and other options 1179 * @payload: the key data in clear and encrypted form 1180 * 1181 * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips 1182 * are supported. 1183 */ 1184 int tpm_unseal_trusted(u32 chip_num, struct trusted_key_payload *payload, 1185 struct trusted_key_options *options) 1186 { 1187 struct tpm_chip *chip; 1188 int rc; 1189 1190 chip = tpm_chip_find_get(chip_num); 1191 if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2)) 1192 return -ENODEV; 1193 1194 rc = tpm2_unseal_trusted(chip, payload, options); 1195 1196 tpm_put_ops(chip); 1197 1198 return rc; 1199 } 1200 EXPORT_SYMBOL_GPL(tpm_unseal_trusted); 1201 1202 static int __init tpm_init(void) 1203 { 1204 int rc; 1205 1206 tpm_class = class_create(THIS_MODULE, "tpm"); 1207 if (IS_ERR(tpm_class)) { 1208 pr_err("couldn't create tpm class\n"); 1209 return PTR_ERR(tpm_class); 1210 } 1211 1212 rc = alloc_chrdev_region(&tpm_devt, 0, TPM_NUM_DEVICES, "tpm"); 1213 if (rc < 0) { 1214 pr_err("tpm: failed to allocate char dev region\n"); 1215 class_destroy(tpm_class); 1216 return rc; 1217 } 1218 1219 return 0; 1220 } 1221 1222 static void __exit tpm_exit(void) 1223 { 1224 idr_destroy(&dev_nums_idr); 1225 class_destroy(tpm_class); 1226 unregister_chrdev_region(tpm_devt, TPM_NUM_DEVICES); 1227 } 1228 1229 subsys_initcall(tpm_init); 1230 module_exit(tpm_exit); 1231 1232 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)"); 1233 MODULE_DESCRIPTION("TPM Driver"); 1234 MODULE_VERSION("2.0"); 1235 MODULE_LICENSE("GPL"); 1236