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 ssize_t rc; 347 u32 count, ordinal; 348 unsigned long stop; 349 350 if (bufsiz < TPM_HEADER_SIZE) 351 return -EINVAL; 352 353 if (bufsiz > TPM_BUFSIZE) 354 bufsiz = TPM_BUFSIZE; 355 356 count = be32_to_cpu(*((__be32 *) (buf + 2))); 357 ordinal = be32_to_cpu(*((__be32 *) (buf + 6))); 358 if (count == 0) 359 return -ENODATA; 360 if (count > bufsiz) { 361 dev_err(&chip->dev, 362 "invalid count value %x %zx\n", count, bufsiz); 363 return -E2BIG; 364 } 365 366 if (!(flags & TPM_TRANSMIT_UNLOCKED)) 367 mutex_lock(&chip->tpm_mutex); 368 369 if (chip->dev.parent) 370 pm_runtime_get_sync(chip->dev.parent); 371 372 rc = chip->ops->send(chip, (u8 *) buf, count); 373 if (rc < 0) { 374 dev_err(&chip->dev, 375 "tpm_transmit: tpm_send: error %zd\n", rc); 376 goto out; 377 } 378 379 if (chip->flags & TPM_CHIP_FLAG_IRQ) 380 goto out_recv; 381 382 if (chip->flags & TPM_CHIP_FLAG_TPM2) 383 stop = jiffies + tpm2_calc_ordinal_duration(chip, ordinal); 384 else 385 stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal); 386 do { 387 u8 status = chip->ops->status(chip); 388 if ((status & chip->ops->req_complete_mask) == 389 chip->ops->req_complete_val) 390 goto out_recv; 391 392 if (chip->ops->req_canceled(chip, status)) { 393 dev_err(&chip->dev, "Operation Canceled\n"); 394 rc = -ECANCELED; 395 goto out; 396 } 397 398 msleep(TPM_TIMEOUT); /* CHECK */ 399 rmb(); 400 } while (time_before(jiffies, stop)); 401 402 chip->ops->cancel(chip); 403 dev_err(&chip->dev, "Operation Timed out\n"); 404 rc = -ETIME; 405 goto out; 406 407 out_recv: 408 rc = chip->ops->recv(chip, (u8 *) buf, bufsiz); 409 if (rc < 0) 410 dev_err(&chip->dev, 411 "tpm_transmit: tpm_recv: error %zd\n", rc); 412 out: 413 if (chip->dev.parent) 414 pm_runtime_put_sync(chip->dev.parent); 415 416 if (!(flags & TPM_TRANSMIT_UNLOCKED)) 417 mutex_unlock(&chip->tpm_mutex); 418 return rc; 419 } 420 421 /** 422 * tmp_transmit_cmd - send a tpm command to the device 423 * The function extracts tpm out header return code 424 * 425 * @chip: TPM chip to use 426 * @buf: TPM command buffer 427 * @bufsiz: length of the buffer 428 * @min_rsp_body_length: minimum expected length of response body 429 * @flags: tpm transmit flags - bitmap 430 * @desc: command description used in the error message 431 * 432 * Return: 433 * 0 when the operation is successful. 434 * A negative number for system errors (errno). 435 * A positive number for a TPM error. 436 */ 437 ssize_t tpm_transmit_cmd(struct tpm_chip *chip, const void *buf, 438 size_t bufsiz, size_t min_rsp_body_length, 439 unsigned int flags, const char *desc) 440 { 441 const struct tpm_output_header *header; 442 int err; 443 ssize_t len; 444 445 len = tpm_transmit(chip, (const u8 *)buf, bufsiz, flags); 446 if (len < 0) 447 return len; 448 else if (len < TPM_HEADER_SIZE) 449 return -EFAULT; 450 451 header = buf; 452 if (len != be32_to_cpu(header->length)) 453 return -EFAULT; 454 455 err = be32_to_cpu(header->return_code); 456 if (err != 0 && desc) 457 dev_err(&chip->dev, "A TPM error (%d) occurred %s\n", err, 458 desc); 459 if (err) 460 return err; 461 462 if (len < min_rsp_body_length + TPM_HEADER_SIZE) 463 return -EFAULT; 464 465 return 0; 466 } 467 468 #define TPM_DIGEST_SIZE 20 469 #define TPM_RET_CODE_IDX 6 470 #define TPM_INTERNAL_RESULT_SIZE 200 471 #define TPM_ORD_GET_CAP cpu_to_be32(101) 472 #define TPM_ORD_GET_RANDOM cpu_to_be32(70) 473 474 static const struct tpm_input_header tpm_getcap_header = { 475 .tag = TPM_TAG_RQU_COMMAND, 476 .length = cpu_to_be32(22), 477 .ordinal = TPM_ORD_GET_CAP 478 }; 479 480 ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap, 481 const char *desc, size_t min_cap_length) 482 { 483 struct tpm_cmd_t tpm_cmd; 484 int rc; 485 486 tpm_cmd.header.in = tpm_getcap_header; 487 if (subcap_id == TPM_CAP_VERSION_1_1 || 488 subcap_id == TPM_CAP_VERSION_1_2) { 489 tpm_cmd.params.getcap_in.cap = cpu_to_be32(subcap_id); 490 /*subcap field not necessary */ 491 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0); 492 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32)); 493 } else { 494 if (subcap_id == TPM_CAP_FLAG_PERM || 495 subcap_id == TPM_CAP_FLAG_VOL) 496 tpm_cmd.params.getcap_in.cap = 497 cpu_to_be32(TPM_CAP_FLAG); 498 else 499 tpm_cmd.params.getcap_in.cap = 500 cpu_to_be32(TPM_CAP_PROP); 501 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4); 502 tpm_cmd.params.getcap_in.subcap = cpu_to_be32(subcap_id); 503 } 504 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 505 min_cap_length, 0, desc); 506 if (!rc) 507 *cap = tpm_cmd.params.getcap_out.cap; 508 return rc; 509 } 510 EXPORT_SYMBOL_GPL(tpm_getcap); 511 512 #define TPM_ORD_STARTUP cpu_to_be32(153) 513 #define TPM_ST_CLEAR cpu_to_be16(1) 514 #define TPM_ST_STATE cpu_to_be16(2) 515 #define TPM_ST_DEACTIVATED cpu_to_be16(3) 516 static const struct tpm_input_header tpm_startup_header = { 517 .tag = TPM_TAG_RQU_COMMAND, 518 .length = cpu_to_be32(12), 519 .ordinal = TPM_ORD_STARTUP 520 }; 521 522 static int tpm_startup(struct tpm_chip *chip, __be16 startup_type) 523 { 524 struct tpm_cmd_t start_cmd; 525 start_cmd.header.in = tpm_startup_header; 526 527 start_cmd.params.startup_in.startup_type = startup_type; 528 return tpm_transmit_cmd(chip, &start_cmd, TPM_INTERNAL_RESULT_SIZE, 0, 529 0, "attempting to start the TPM"); 530 } 531 532 int tpm_get_timeouts(struct tpm_chip *chip) 533 { 534 cap_t cap; 535 unsigned long timeout_old[4], timeout_chip[4], timeout_eff[4]; 536 ssize_t rc; 537 538 if (chip->flags & TPM_CHIP_FLAG_HAVE_TIMEOUTS) 539 return 0; 540 541 if (chip->flags & TPM_CHIP_FLAG_TPM2) { 542 /* Fixed timeouts for TPM2 */ 543 chip->timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A); 544 chip->timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B); 545 chip->timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C); 546 chip->timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D); 547 chip->duration[TPM_SHORT] = 548 msecs_to_jiffies(TPM2_DURATION_SHORT); 549 chip->duration[TPM_MEDIUM] = 550 msecs_to_jiffies(TPM2_DURATION_MEDIUM); 551 chip->duration[TPM_LONG] = 552 msecs_to_jiffies(TPM2_DURATION_LONG); 553 554 chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS; 555 return 0; 556 } 557 558 rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, NULL, 559 sizeof(cap.timeout)); 560 if (rc == TPM_ERR_INVALID_POSTINIT) { 561 /* The TPM is not started, we are the first to talk to it. 562 Execute a startup command. */ 563 dev_info(&chip->dev, "Issuing TPM_STARTUP\n"); 564 if (tpm_startup(chip, TPM_ST_CLEAR)) 565 return rc; 566 567 rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, 568 "attempting to determine the timeouts", 569 sizeof(cap.timeout)); 570 } 571 572 if (rc) { 573 dev_err(&chip->dev, 574 "A TPM error (%zd) occurred attempting to determine the timeouts\n", 575 rc); 576 return rc; 577 } 578 579 timeout_old[0] = jiffies_to_usecs(chip->timeout_a); 580 timeout_old[1] = jiffies_to_usecs(chip->timeout_b); 581 timeout_old[2] = jiffies_to_usecs(chip->timeout_c); 582 timeout_old[3] = jiffies_to_usecs(chip->timeout_d); 583 timeout_chip[0] = be32_to_cpu(cap.timeout.a); 584 timeout_chip[1] = be32_to_cpu(cap.timeout.b); 585 timeout_chip[2] = be32_to_cpu(cap.timeout.c); 586 timeout_chip[3] = be32_to_cpu(cap.timeout.d); 587 memcpy(timeout_eff, timeout_chip, sizeof(timeout_eff)); 588 589 /* 590 * Provide ability for vendor overrides of timeout values in case 591 * of misreporting. 592 */ 593 if (chip->ops->update_timeouts != NULL) 594 chip->timeout_adjusted = 595 chip->ops->update_timeouts(chip, timeout_eff); 596 597 if (!chip->timeout_adjusted) { 598 /* Restore default if chip reported 0 */ 599 int i; 600 601 for (i = 0; i < ARRAY_SIZE(timeout_eff); i++) { 602 if (timeout_eff[i]) 603 continue; 604 605 timeout_eff[i] = timeout_old[i]; 606 chip->timeout_adjusted = true; 607 } 608 609 if (timeout_eff[0] != 0 && timeout_eff[0] < 1000) { 610 /* timeouts in msec rather usec */ 611 for (i = 0; i != ARRAY_SIZE(timeout_eff); i++) 612 timeout_eff[i] *= 1000; 613 chip->timeout_adjusted = true; 614 } 615 } 616 617 /* Report adjusted timeouts */ 618 if (chip->timeout_adjusted) { 619 dev_info(&chip->dev, 620 HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n", 621 timeout_chip[0], timeout_eff[0], 622 timeout_chip[1], timeout_eff[1], 623 timeout_chip[2], timeout_eff[2], 624 timeout_chip[3], timeout_eff[3]); 625 } 626 627 chip->timeout_a = usecs_to_jiffies(timeout_eff[0]); 628 chip->timeout_b = usecs_to_jiffies(timeout_eff[1]); 629 chip->timeout_c = usecs_to_jiffies(timeout_eff[2]); 630 chip->timeout_d = usecs_to_jiffies(timeout_eff[3]); 631 632 rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap, 633 "attempting to determine the durations", 634 sizeof(cap.duration)); 635 if (rc) 636 return rc; 637 638 chip->duration[TPM_SHORT] = 639 usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short)); 640 chip->duration[TPM_MEDIUM] = 641 usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium)); 642 chip->duration[TPM_LONG] = 643 usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long)); 644 645 /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above 646 * value wrong and apparently reports msecs rather than usecs. So we 647 * fix up the resulting too-small TPM_SHORT value to make things work. 648 * We also scale the TPM_MEDIUM and -_LONG values by 1000. 649 */ 650 if (chip->duration[TPM_SHORT] < (HZ / 100)) { 651 chip->duration[TPM_SHORT] = HZ; 652 chip->duration[TPM_MEDIUM] *= 1000; 653 chip->duration[TPM_LONG] *= 1000; 654 chip->duration_adjusted = true; 655 dev_info(&chip->dev, "Adjusting TPM timeout parameters."); 656 } 657 658 chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS; 659 return 0; 660 } 661 EXPORT_SYMBOL_GPL(tpm_get_timeouts); 662 663 #define TPM_ORD_CONTINUE_SELFTEST 83 664 #define CONTINUE_SELFTEST_RESULT_SIZE 10 665 666 static const struct tpm_input_header continue_selftest_header = { 667 .tag = TPM_TAG_RQU_COMMAND, 668 .length = cpu_to_be32(10), 669 .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST), 670 }; 671 672 /** 673 * tpm_continue_selftest -- run TPM's selftest 674 * @chip: TPM chip to use 675 * 676 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing 677 * a TPM error code. 678 */ 679 static int tpm_continue_selftest(struct tpm_chip *chip) 680 { 681 int rc; 682 struct tpm_cmd_t cmd; 683 684 cmd.header.in = continue_selftest_header; 685 rc = tpm_transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE, 0, 0, 686 "continue selftest"); 687 return rc; 688 } 689 690 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21) 691 #define READ_PCR_RESULT_SIZE 30 692 #define READ_PCR_RESULT_BODY_SIZE 20 693 static const struct tpm_input_header pcrread_header = { 694 .tag = TPM_TAG_RQU_COMMAND, 695 .length = cpu_to_be32(14), 696 .ordinal = TPM_ORDINAL_PCRREAD 697 }; 698 699 int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) 700 { 701 int rc; 702 struct tpm_cmd_t cmd; 703 704 cmd.header.in = pcrread_header; 705 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx); 706 rc = tpm_transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE, 707 READ_PCR_RESULT_BODY_SIZE, 0, 708 "attempting to read a pcr value"); 709 710 if (rc == 0) 711 memcpy(res_buf, cmd.params.pcrread_out.pcr_result, 712 TPM_DIGEST_SIZE); 713 return rc; 714 } 715 716 /** 717 * tpm_is_tpm2 - is the chip a TPM2 chip? 718 * @chip_num: tpm idx # or ANY 719 * 720 * Returns < 0 on error, and 1 or 0 on success depending whether the chip 721 * is a TPM2 chip. 722 */ 723 int tpm_is_tpm2(u32 chip_num) 724 { 725 struct tpm_chip *chip; 726 int rc; 727 728 chip = tpm_chip_find_get(chip_num); 729 if (chip == NULL) 730 return -ENODEV; 731 732 rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0; 733 734 tpm_put_ops(chip); 735 736 return rc; 737 } 738 EXPORT_SYMBOL_GPL(tpm_is_tpm2); 739 740 /** 741 * tpm_pcr_read - read a pcr value 742 * @chip_num: tpm idx # or ANY 743 * @pcr_idx: pcr idx to retrieve 744 * @res_buf: TPM_PCR value 745 * size of res_buf is 20 bytes (or NULL if you don't care) 746 * 747 * The TPM driver should be built-in, but for whatever reason it 748 * isn't, protect against the chip disappearing, by incrementing 749 * the module usage count. 750 */ 751 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf) 752 { 753 struct tpm_chip *chip; 754 int rc; 755 756 chip = tpm_chip_find_get(chip_num); 757 if (chip == NULL) 758 return -ENODEV; 759 if (chip->flags & TPM_CHIP_FLAG_TPM2) 760 rc = tpm2_pcr_read(chip, pcr_idx, res_buf); 761 else 762 rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf); 763 tpm_put_ops(chip); 764 return rc; 765 } 766 EXPORT_SYMBOL_GPL(tpm_pcr_read); 767 768 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20) 769 #define EXTEND_PCR_RESULT_SIZE 34 770 #define EXTEND_PCR_RESULT_BODY_SIZE 20 771 static const struct tpm_input_header pcrextend_header = { 772 .tag = TPM_TAG_RQU_COMMAND, 773 .length = cpu_to_be32(34), 774 .ordinal = TPM_ORD_PCR_EXTEND 775 }; 776 777 /** 778 * tpm_pcr_extend - extend pcr value with hash 779 * @chip_num: tpm idx # or AN& 780 * @pcr_idx: pcr idx to extend 781 * @hash: hash value used to extend pcr value 782 * 783 * The TPM driver should be built-in, but for whatever reason it 784 * isn't, protect against the chip disappearing, by incrementing 785 * the module usage count. 786 */ 787 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash) 788 { 789 struct tpm_cmd_t cmd; 790 int rc; 791 struct tpm_chip *chip; 792 struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)]; 793 u32 count = 0; 794 int i; 795 796 chip = tpm_chip_find_get(chip_num); 797 if (chip == NULL) 798 return -ENODEV; 799 800 if (chip->flags & TPM_CHIP_FLAG_TPM2) { 801 memset(digest_list, 0, sizeof(digest_list)); 802 803 for (i = 0; i < ARRAY_SIZE(chip->active_banks) && 804 chip->active_banks[i] != TPM2_ALG_ERROR; i++) { 805 digest_list[i].alg_id = chip->active_banks[i]; 806 memcpy(digest_list[i].digest, hash, TPM_DIGEST_SIZE); 807 count++; 808 } 809 810 rc = tpm2_pcr_extend(chip, pcr_idx, count, digest_list); 811 tpm_put_ops(chip); 812 return rc; 813 } 814 815 cmd.header.in = pcrextend_header; 816 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx); 817 memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE); 818 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE, 819 EXTEND_PCR_RESULT_BODY_SIZE, 0, 820 "attempting extend a PCR value"); 821 822 tpm_put_ops(chip); 823 return rc; 824 } 825 EXPORT_SYMBOL_GPL(tpm_pcr_extend); 826 827 /** 828 * tpm_do_selftest - have the TPM continue its selftest and wait until it 829 * can receive further commands 830 * @chip: TPM chip to use 831 * 832 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing 833 * a TPM error code. 834 */ 835 int tpm_do_selftest(struct tpm_chip *chip) 836 { 837 int rc; 838 unsigned int loops; 839 unsigned int delay_msec = 100; 840 unsigned long duration; 841 u8 dummy[TPM_DIGEST_SIZE]; 842 843 duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST); 844 845 loops = jiffies_to_msecs(duration) / delay_msec; 846 847 rc = tpm_continue_selftest(chip); 848 /* This may fail if there was no TPM driver during a suspend/resume 849 * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST) 850 */ 851 if (rc) 852 return rc; 853 854 do { 855 /* Attempt to read a PCR value */ 856 rc = tpm_pcr_read_dev(chip, 0, dummy); 857 858 /* Some buggy TPMs will not respond to tpm_tis_ready() for 859 * around 300ms while the self test is ongoing, keep trying 860 * until the self test duration expires. */ 861 if (rc == -ETIME) { 862 dev_info( 863 &chip->dev, HW_ERR 864 "TPM command timed out during continue self test"); 865 msleep(delay_msec); 866 continue; 867 } 868 869 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) { 870 dev_info(&chip->dev, 871 "TPM is disabled/deactivated (0x%X)\n", rc); 872 /* TPM is disabled and/or deactivated; driver can 873 * proceed and TPM does handle commands for 874 * suspend/resume correctly 875 */ 876 return 0; 877 } 878 if (rc != TPM_WARN_DOING_SELFTEST) 879 return rc; 880 msleep(delay_msec); 881 } while (--loops > 0); 882 883 return rc; 884 } 885 EXPORT_SYMBOL_GPL(tpm_do_selftest); 886 887 /** 888 * tpm1_auto_startup - Perform the standard automatic TPM initialization 889 * sequence 890 * @chip: TPM chip to use 891 * 892 * Returns 0 on success, < 0 in case of fatal error. 893 */ 894 int tpm1_auto_startup(struct tpm_chip *chip) 895 { 896 int rc; 897 898 rc = tpm_get_timeouts(chip); 899 if (rc) 900 goto out; 901 rc = tpm_do_selftest(chip); 902 if (rc) { 903 dev_err(&chip->dev, "TPM self test failed\n"); 904 goto out; 905 } 906 907 return rc; 908 out: 909 if (rc > 0) 910 rc = -ENODEV; 911 return rc; 912 } 913 914 int tpm_send(u32 chip_num, void *cmd, size_t buflen) 915 { 916 struct tpm_chip *chip; 917 int rc; 918 919 chip = tpm_chip_find_get(chip_num); 920 if (chip == NULL) 921 return -ENODEV; 922 923 rc = tpm_transmit_cmd(chip, cmd, buflen, 0, 0, "attempting tpm_cmd"); 924 925 tpm_put_ops(chip); 926 return rc; 927 } 928 EXPORT_SYMBOL_GPL(tpm_send); 929 930 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask, 931 bool check_cancel, bool *canceled) 932 { 933 u8 status = chip->ops->status(chip); 934 935 *canceled = false; 936 if ((status & mask) == mask) 937 return true; 938 if (check_cancel && chip->ops->req_canceled(chip, status)) { 939 *canceled = true; 940 return true; 941 } 942 return false; 943 } 944 945 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout, 946 wait_queue_head_t *queue, bool check_cancel) 947 { 948 unsigned long stop; 949 long rc; 950 u8 status; 951 bool canceled = false; 952 953 /* check current status */ 954 status = chip->ops->status(chip); 955 if ((status & mask) == mask) 956 return 0; 957 958 stop = jiffies + timeout; 959 960 if (chip->flags & TPM_CHIP_FLAG_IRQ) { 961 again: 962 timeout = stop - jiffies; 963 if ((long)timeout <= 0) 964 return -ETIME; 965 rc = wait_event_interruptible_timeout(*queue, 966 wait_for_tpm_stat_cond(chip, mask, check_cancel, 967 &canceled), 968 timeout); 969 if (rc > 0) { 970 if (canceled) 971 return -ECANCELED; 972 return 0; 973 } 974 if (rc == -ERESTARTSYS && freezing(current)) { 975 clear_thread_flag(TIF_SIGPENDING); 976 goto again; 977 } 978 } else { 979 do { 980 msleep(TPM_TIMEOUT); 981 status = chip->ops->status(chip); 982 if ((status & mask) == mask) 983 return 0; 984 } while (time_before(jiffies, stop)); 985 } 986 return -ETIME; 987 } 988 EXPORT_SYMBOL_GPL(wait_for_tpm_stat); 989 990 #define TPM_ORD_SAVESTATE cpu_to_be32(152) 991 #define SAVESTATE_RESULT_SIZE 10 992 993 static const struct tpm_input_header savestate_header = { 994 .tag = TPM_TAG_RQU_COMMAND, 995 .length = cpu_to_be32(10), 996 .ordinal = TPM_ORD_SAVESTATE 997 }; 998 999 /* 1000 * We are about to suspend. Save the TPM state 1001 * so that it can be restored. 1002 */ 1003 int tpm_pm_suspend(struct device *dev) 1004 { 1005 struct tpm_chip *chip = dev_get_drvdata(dev); 1006 struct tpm_cmd_t cmd; 1007 int rc, try; 1008 1009 u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 }; 1010 1011 if (chip == NULL) 1012 return -ENODEV; 1013 1014 if (chip->flags & TPM_CHIP_FLAG_TPM2) { 1015 tpm2_shutdown(chip, TPM2_SU_STATE); 1016 return 0; 1017 } 1018 1019 /* for buggy tpm, flush pcrs with extend to selected dummy */ 1020 if (tpm_suspend_pcr) { 1021 cmd.header.in = pcrextend_header; 1022 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr); 1023 memcpy(cmd.params.pcrextend_in.hash, dummy_hash, 1024 TPM_DIGEST_SIZE); 1025 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE, 1026 EXTEND_PCR_RESULT_BODY_SIZE, 0, 1027 "extending dummy pcr before suspend"); 1028 } 1029 1030 /* now do the actual savestate */ 1031 for (try = 0; try < TPM_RETRY; try++) { 1032 cmd.header.in = savestate_header; 1033 rc = tpm_transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, 0, 1034 0, NULL); 1035 1036 /* 1037 * If the TPM indicates that it is too busy to respond to 1038 * this command then retry before giving up. It can take 1039 * several seconds for this TPM to be ready. 1040 * 1041 * This can happen if the TPM has already been sent the 1042 * SaveState command before the driver has loaded. TCG 1.2 1043 * specification states that any communication after SaveState 1044 * may cause the TPM to invalidate previously saved state. 1045 */ 1046 if (rc != TPM_WARN_RETRY) 1047 break; 1048 msleep(TPM_TIMEOUT_RETRY); 1049 } 1050 1051 if (rc) 1052 dev_err(&chip->dev, 1053 "Error (%d) sending savestate before suspend\n", rc); 1054 else if (try > 0) 1055 dev_warn(&chip->dev, "TPM savestate took %dms\n", 1056 try * TPM_TIMEOUT_RETRY); 1057 1058 return rc; 1059 } 1060 EXPORT_SYMBOL_GPL(tpm_pm_suspend); 1061 1062 /* 1063 * Resume from a power safe. The BIOS already restored 1064 * the TPM state. 1065 */ 1066 int tpm_pm_resume(struct device *dev) 1067 { 1068 struct tpm_chip *chip = dev_get_drvdata(dev); 1069 1070 if (chip == NULL) 1071 return -ENODEV; 1072 1073 return 0; 1074 } 1075 EXPORT_SYMBOL_GPL(tpm_pm_resume); 1076 1077 #define TPM_GETRANDOM_RESULT_SIZE 18 1078 static const struct tpm_input_header tpm_getrandom_header = { 1079 .tag = TPM_TAG_RQU_COMMAND, 1080 .length = cpu_to_be32(14), 1081 .ordinal = TPM_ORD_GET_RANDOM 1082 }; 1083 1084 /** 1085 * tpm_get_random() - Get random bytes from the tpm's RNG 1086 * @chip_num: A specific chip number for the request or TPM_ANY_NUM 1087 * @out: destination buffer for the random bytes 1088 * @max: the max number of bytes to write to @out 1089 * 1090 * Returns < 0 on error and the number of bytes read on success 1091 */ 1092 int tpm_get_random(u32 chip_num, u8 *out, size_t max) 1093 { 1094 struct tpm_chip *chip; 1095 struct tpm_cmd_t tpm_cmd; 1096 u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA), rlength; 1097 int err, total = 0, retries = 5; 1098 u8 *dest = out; 1099 1100 if (!out || !num_bytes || max > TPM_MAX_RNG_DATA) 1101 return -EINVAL; 1102 1103 chip = tpm_chip_find_get(chip_num); 1104 if (chip == NULL) 1105 return -ENODEV; 1106 1107 if (chip->flags & TPM_CHIP_FLAG_TPM2) { 1108 err = tpm2_get_random(chip, out, max); 1109 tpm_put_ops(chip); 1110 return err; 1111 } 1112 1113 do { 1114 tpm_cmd.header.in = tpm_getrandom_header; 1115 tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes); 1116 1117 err = tpm_transmit_cmd(chip, &tpm_cmd, 1118 TPM_GETRANDOM_RESULT_SIZE + num_bytes, 1119 offsetof(struct tpm_getrandom_out, 1120 rng_data), 1121 0, "attempting get random"); 1122 if (err) 1123 break; 1124 1125 recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len); 1126 1127 rlength = be32_to_cpu(tpm_cmd.header.out.length); 1128 if (rlength < offsetof(struct tpm_getrandom_out, rng_data) + 1129 recd) { 1130 total = -EFAULT; 1131 break; 1132 } 1133 memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd); 1134 1135 dest += recd; 1136 total += recd; 1137 num_bytes -= recd; 1138 } while (retries-- && total < max); 1139 1140 tpm_put_ops(chip); 1141 return total ? total : -EIO; 1142 } 1143 EXPORT_SYMBOL_GPL(tpm_get_random); 1144 1145 /** 1146 * tpm_seal_trusted() - seal a trusted key 1147 * @chip_num: A specific chip number for the request or TPM_ANY_NUM 1148 * @options: authentication values and other options 1149 * @payload: the key data in clear and encrypted form 1150 * 1151 * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips 1152 * are supported. 1153 */ 1154 int tpm_seal_trusted(u32 chip_num, struct trusted_key_payload *payload, 1155 struct trusted_key_options *options) 1156 { 1157 struct tpm_chip *chip; 1158 int rc; 1159 1160 chip = tpm_chip_find_get(chip_num); 1161 if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2)) 1162 return -ENODEV; 1163 1164 rc = tpm2_seal_trusted(chip, payload, options); 1165 1166 tpm_put_ops(chip); 1167 return rc; 1168 } 1169 EXPORT_SYMBOL_GPL(tpm_seal_trusted); 1170 1171 /** 1172 * tpm_unseal_trusted() - unseal a trusted key 1173 * @chip_num: A specific chip number for the request or TPM_ANY_NUM 1174 * @options: authentication values and other options 1175 * @payload: the key data in clear and encrypted form 1176 * 1177 * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips 1178 * are supported. 1179 */ 1180 int tpm_unseal_trusted(u32 chip_num, struct trusted_key_payload *payload, 1181 struct trusted_key_options *options) 1182 { 1183 struct tpm_chip *chip; 1184 int rc; 1185 1186 chip = tpm_chip_find_get(chip_num); 1187 if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2)) 1188 return -ENODEV; 1189 1190 rc = tpm2_unseal_trusted(chip, payload, options); 1191 1192 tpm_put_ops(chip); 1193 1194 return rc; 1195 } 1196 EXPORT_SYMBOL_GPL(tpm_unseal_trusted); 1197 1198 static int __init tpm_init(void) 1199 { 1200 int rc; 1201 1202 tpm_class = class_create(THIS_MODULE, "tpm"); 1203 if (IS_ERR(tpm_class)) { 1204 pr_err("couldn't create tpm class\n"); 1205 return PTR_ERR(tpm_class); 1206 } 1207 1208 rc = alloc_chrdev_region(&tpm_devt, 0, TPM_NUM_DEVICES, "tpm"); 1209 if (rc < 0) { 1210 pr_err("tpm: failed to allocate char dev region\n"); 1211 class_destroy(tpm_class); 1212 return rc; 1213 } 1214 1215 return 0; 1216 } 1217 1218 static void __exit tpm_exit(void) 1219 { 1220 idr_destroy(&dev_nums_idr); 1221 class_destroy(tpm_class); 1222 unregister_chrdev_region(tpm_devt, TPM_NUM_DEVICES); 1223 } 1224 1225 subsys_initcall(tpm_init); 1226 module_exit(tpm_exit); 1227 1228 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)"); 1229 MODULE_DESCRIPTION("TPM Driver"); 1230 MODULE_VERSION("2.0"); 1231 MODULE_LICENSE("GPL"); 1232