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 33 #include "tpm.h" 34 #include "tpm_eventlog.h" 35 36 #define TPM_MAX_ORDINAL 243 37 #define TSC_MAX_ORDINAL 12 38 #define TPM_PROTECTED_COMMAND 0x00 39 #define TPM_CONNECTION_COMMAND 0x40 40 41 /* 42 * Bug workaround - some TPM's don't flush the most 43 * recently changed pcr on suspend, so force the flush 44 * with an extend to the selected _unused_ non-volatile pcr. 45 */ 46 static int tpm_suspend_pcr; 47 module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644); 48 MODULE_PARM_DESC(suspend_pcr, 49 "PCR to use for dummy writes to faciltate flush on suspend."); 50 51 /* 52 * Array with one entry per ordinal defining the maximum amount 53 * of time the chip could take to return the result. The ordinal 54 * designation of short, medium or long is defined in a table in 55 * TCG Specification TPM Main Part 2 TPM Structures Section 17. The 56 * values of the SHORT, MEDIUM, and LONG durations are retrieved 57 * from the chip during initialization with a call to tpm_get_timeouts. 58 */ 59 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = { 60 TPM_UNDEFINED, /* 0 */ 61 TPM_UNDEFINED, 62 TPM_UNDEFINED, 63 TPM_UNDEFINED, 64 TPM_UNDEFINED, 65 TPM_UNDEFINED, /* 5 */ 66 TPM_UNDEFINED, 67 TPM_UNDEFINED, 68 TPM_UNDEFINED, 69 TPM_UNDEFINED, 70 TPM_SHORT, /* 10 */ 71 TPM_SHORT, 72 TPM_MEDIUM, 73 TPM_LONG, 74 TPM_LONG, 75 TPM_MEDIUM, /* 15 */ 76 TPM_SHORT, 77 TPM_SHORT, 78 TPM_MEDIUM, 79 TPM_LONG, 80 TPM_SHORT, /* 20 */ 81 TPM_SHORT, 82 TPM_MEDIUM, 83 TPM_MEDIUM, 84 TPM_MEDIUM, 85 TPM_SHORT, /* 25 */ 86 TPM_SHORT, 87 TPM_MEDIUM, 88 TPM_SHORT, 89 TPM_SHORT, 90 TPM_MEDIUM, /* 30 */ 91 TPM_LONG, 92 TPM_MEDIUM, 93 TPM_SHORT, 94 TPM_SHORT, 95 TPM_SHORT, /* 35 */ 96 TPM_MEDIUM, 97 TPM_MEDIUM, 98 TPM_UNDEFINED, 99 TPM_UNDEFINED, 100 TPM_MEDIUM, /* 40 */ 101 TPM_LONG, 102 TPM_MEDIUM, 103 TPM_SHORT, 104 TPM_SHORT, 105 TPM_SHORT, /* 45 */ 106 TPM_SHORT, 107 TPM_SHORT, 108 TPM_SHORT, 109 TPM_LONG, 110 TPM_MEDIUM, /* 50 */ 111 TPM_MEDIUM, 112 TPM_UNDEFINED, 113 TPM_UNDEFINED, 114 TPM_UNDEFINED, 115 TPM_UNDEFINED, /* 55 */ 116 TPM_UNDEFINED, 117 TPM_UNDEFINED, 118 TPM_UNDEFINED, 119 TPM_UNDEFINED, 120 TPM_MEDIUM, /* 60 */ 121 TPM_MEDIUM, 122 TPM_MEDIUM, 123 TPM_SHORT, 124 TPM_SHORT, 125 TPM_MEDIUM, /* 65 */ 126 TPM_UNDEFINED, 127 TPM_UNDEFINED, 128 TPM_UNDEFINED, 129 TPM_UNDEFINED, 130 TPM_SHORT, /* 70 */ 131 TPM_SHORT, 132 TPM_UNDEFINED, 133 TPM_UNDEFINED, 134 TPM_UNDEFINED, 135 TPM_UNDEFINED, /* 75 */ 136 TPM_UNDEFINED, 137 TPM_UNDEFINED, 138 TPM_UNDEFINED, 139 TPM_UNDEFINED, 140 TPM_LONG, /* 80 */ 141 TPM_UNDEFINED, 142 TPM_MEDIUM, 143 TPM_LONG, 144 TPM_SHORT, 145 TPM_UNDEFINED, /* 85 */ 146 TPM_UNDEFINED, 147 TPM_UNDEFINED, 148 TPM_UNDEFINED, 149 TPM_UNDEFINED, 150 TPM_SHORT, /* 90 */ 151 TPM_SHORT, 152 TPM_SHORT, 153 TPM_SHORT, 154 TPM_SHORT, 155 TPM_UNDEFINED, /* 95 */ 156 TPM_UNDEFINED, 157 TPM_UNDEFINED, 158 TPM_UNDEFINED, 159 TPM_UNDEFINED, 160 TPM_MEDIUM, /* 100 */ 161 TPM_SHORT, 162 TPM_SHORT, 163 TPM_UNDEFINED, 164 TPM_UNDEFINED, 165 TPM_UNDEFINED, /* 105 */ 166 TPM_UNDEFINED, 167 TPM_UNDEFINED, 168 TPM_UNDEFINED, 169 TPM_UNDEFINED, 170 TPM_SHORT, /* 110 */ 171 TPM_SHORT, 172 TPM_SHORT, 173 TPM_SHORT, 174 TPM_SHORT, 175 TPM_SHORT, /* 115 */ 176 TPM_SHORT, 177 TPM_SHORT, 178 TPM_UNDEFINED, 179 TPM_UNDEFINED, 180 TPM_LONG, /* 120 */ 181 TPM_LONG, 182 TPM_MEDIUM, 183 TPM_UNDEFINED, 184 TPM_SHORT, 185 TPM_SHORT, /* 125 */ 186 TPM_SHORT, 187 TPM_LONG, 188 TPM_SHORT, 189 TPM_SHORT, 190 TPM_SHORT, /* 130 */ 191 TPM_MEDIUM, 192 TPM_UNDEFINED, 193 TPM_SHORT, 194 TPM_MEDIUM, 195 TPM_UNDEFINED, /* 135 */ 196 TPM_UNDEFINED, 197 TPM_UNDEFINED, 198 TPM_UNDEFINED, 199 TPM_UNDEFINED, 200 TPM_SHORT, /* 140 */ 201 TPM_SHORT, 202 TPM_UNDEFINED, 203 TPM_UNDEFINED, 204 TPM_UNDEFINED, 205 TPM_UNDEFINED, /* 145 */ 206 TPM_UNDEFINED, 207 TPM_UNDEFINED, 208 TPM_UNDEFINED, 209 TPM_UNDEFINED, 210 TPM_SHORT, /* 150 */ 211 TPM_MEDIUM, 212 TPM_MEDIUM, 213 TPM_SHORT, 214 TPM_SHORT, 215 TPM_UNDEFINED, /* 155 */ 216 TPM_UNDEFINED, 217 TPM_UNDEFINED, 218 TPM_UNDEFINED, 219 TPM_UNDEFINED, 220 TPM_SHORT, /* 160 */ 221 TPM_SHORT, 222 TPM_SHORT, 223 TPM_SHORT, 224 TPM_UNDEFINED, 225 TPM_UNDEFINED, /* 165 */ 226 TPM_UNDEFINED, 227 TPM_UNDEFINED, 228 TPM_UNDEFINED, 229 TPM_UNDEFINED, 230 TPM_LONG, /* 170 */ 231 TPM_UNDEFINED, 232 TPM_UNDEFINED, 233 TPM_UNDEFINED, 234 TPM_UNDEFINED, 235 TPM_UNDEFINED, /* 175 */ 236 TPM_UNDEFINED, 237 TPM_UNDEFINED, 238 TPM_UNDEFINED, 239 TPM_UNDEFINED, 240 TPM_MEDIUM, /* 180 */ 241 TPM_SHORT, 242 TPM_MEDIUM, 243 TPM_MEDIUM, 244 TPM_MEDIUM, 245 TPM_MEDIUM, /* 185 */ 246 TPM_SHORT, 247 TPM_UNDEFINED, 248 TPM_UNDEFINED, 249 TPM_UNDEFINED, 250 TPM_UNDEFINED, /* 190 */ 251 TPM_UNDEFINED, 252 TPM_UNDEFINED, 253 TPM_UNDEFINED, 254 TPM_UNDEFINED, 255 TPM_UNDEFINED, /* 195 */ 256 TPM_UNDEFINED, 257 TPM_UNDEFINED, 258 TPM_UNDEFINED, 259 TPM_UNDEFINED, 260 TPM_SHORT, /* 200 */ 261 TPM_UNDEFINED, 262 TPM_UNDEFINED, 263 TPM_UNDEFINED, 264 TPM_SHORT, 265 TPM_SHORT, /* 205 */ 266 TPM_SHORT, 267 TPM_SHORT, 268 TPM_SHORT, 269 TPM_SHORT, 270 TPM_MEDIUM, /* 210 */ 271 TPM_UNDEFINED, 272 TPM_MEDIUM, 273 TPM_MEDIUM, 274 TPM_MEDIUM, 275 TPM_UNDEFINED, /* 215 */ 276 TPM_MEDIUM, 277 TPM_UNDEFINED, 278 TPM_UNDEFINED, 279 TPM_SHORT, 280 TPM_SHORT, /* 220 */ 281 TPM_SHORT, 282 TPM_SHORT, 283 TPM_SHORT, 284 TPM_SHORT, 285 TPM_UNDEFINED, /* 225 */ 286 TPM_UNDEFINED, 287 TPM_UNDEFINED, 288 TPM_UNDEFINED, 289 TPM_UNDEFINED, 290 TPM_SHORT, /* 230 */ 291 TPM_LONG, 292 TPM_MEDIUM, 293 TPM_UNDEFINED, 294 TPM_UNDEFINED, 295 TPM_UNDEFINED, /* 235 */ 296 TPM_UNDEFINED, 297 TPM_UNDEFINED, 298 TPM_UNDEFINED, 299 TPM_UNDEFINED, 300 TPM_SHORT, /* 240 */ 301 TPM_UNDEFINED, 302 TPM_MEDIUM, 303 }; 304 305 /* 306 * Returns max number of jiffies to wait 307 */ 308 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip, 309 u32 ordinal) 310 { 311 int duration_idx = TPM_UNDEFINED; 312 int duration = 0; 313 314 /* 315 * We only have a duration table for protected commands, where the upper 316 * 16 bits are 0. For the few other ordinals the fallback will be used. 317 */ 318 if (ordinal < TPM_MAX_ORDINAL) 319 duration_idx = tpm_ordinal_duration[ordinal]; 320 321 if (duration_idx != TPM_UNDEFINED) 322 duration = chip->vendor.duration[duration_idx]; 323 if (duration <= 0) 324 return 2 * 60 * HZ; 325 else 326 return duration; 327 } 328 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration); 329 330 /* 331 * Internal kernel interface to transmit TPM commands 332 */ 333 ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf, 334 size_t bufsiz) 335 { 336 ssize_t rc; 337 u32 count, ordinal; 338 unsigned long stop; 339 340 if (bufsiz > TPM_BUFSIZE) 341 bufsiz = TPM_BUFSIZE; 342 343 count = be32_to_cpu(*((__be32 *) (buf + 2))); 344 ordinal = be32_to_cpu(*((__be32 *) (buf + 6))); 345 if (count == 0) 346 return -ENODATA; 347 if (count > bufsiz) { 348 dev_err(chip->pdev, 349 "invalid count value %x %zx\n", count, bufsiz); 350 return -E2BIG; 351 } 352 353 mutex_lock(&chip->tpm_mutex); 354 355 rc = chip->ops->send(chip, (u8 *) buf, count); 356 if (rc < 0) { 357 dev_err(chip->pdev, 358 "tpm_transmit: tpm_send: error %zd\n", rc); 359 goto out; 360 } 361 362 if (chip->vendor.irq) 363 goto out_recv; 364 365 if (chip->flags & TPM_CHIP_FLAG_TPM2) 366 stop = jiffies + tpm2_calc_ordinal_duration(chip, ordinal); 367 else 368 stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal); 369 do { 370 u8 status = chip->ops->status(chip); 371 if ((status & chip->ops->req_complete_mask) == 372 chip->ops->req_complete_val) 373 goto out_recv; 374 375 if (chip->ops->req_canceled(chip, status)) { 376 dev_err(chip->pdev, "Operation Canceled\n"); 377 rc = -ECANCELED; 378 goto out; 379 } 380 381 msleep(TPM_TIMEOUT); /* CHECK */ 382 rmb(); 383 } while (time_before(jiffies, stop)); 384 385 chip->ops->cancel(chip); 386 dev_err(chip->pdev, "Operation Timed out\n"); 387 rc = -ETIME; 388 goto out; 389 390 out_recv: 391 rc = chip->ops->recv(chip, (u8 *) buf, bufsiz); 392 if (rc < 0) 393 dev_err(chip->pdev, 394 "tpm_transmit: tpm_recv: error %zd\n", rc); 395 out: 396 mutex_unlock(&chip->tpm_mutex); 397 return rc; 398 } 399 400 #define TPM_DIGEST_SIZE 20 401 #define TPM_RET_CODE_IDX 6 402 403 ssize_t tpm_transmit_cmd(struct tpm_chip *chip, void *cmd, 404 int len, const char *desc) 405 { 406 struct tpm_output_header *header; 407 int err; 408 409 len = tpm_transmit(chip, (u8 *) cmd, len); 410 if (len < 0) 411 return len; 412 else if (len < TPM_HEADER_SIZE) 413 return -EFAULT; 414 415 header = cmd; 416 417 err = be32_to_cpu(header->return_code); 418 if (err != 0 && desc) 419 dev_err(chip->pdev, "A TPM error (%d) occurred %s\n", err, 420 desc); 421 422 return err; 423 } 424 425 #define TPM_INTERNAL_RESULT_SIZE 200 426 #define TPM_ORD_GET_CAP cpu_to_be32(101) 427 #define TPM_ORD_GET_RANDOM cpu_to_be32(70) 428 429 static const struct tpm_input_header tpm_getcap_header = { 430 .tag = TPM_TAG_RQU_COMMAND, 431 .length = cpu_to_be32(22), 432 .ordinal = TPM_ORD_GET_CAP 433 }; 434 435 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap, 436 const char *desc) 437 { 438 struct tpm_cmd_t tpm_cmd; 439 int rc; 440 struct tpm_chip *chip = dev_get_drvdata(dev); 441 442 tpm_cmd.header.in = tpm_getcap_header; 443 if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) { 444 tpm_cmd.params.getcap_in.cap = subcap_id; 445 /*subcap field not necessary */ 446 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0); 447 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32)); 448 } else { 449 if (subcap_id == TPM_CAP_FLAG_PERM || 450 subcap_id == TPM_CAP_FLAG_VOL) 451 tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG; 452 else 453 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP; 454 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4); 455 tpm_cmd.params.getcap_in.subcap = subcap_id; 456 } 457 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc); 458 if (!rc) 459 *cap = tpm_cmd.params.getcap_out.cap; 460 return rc; 461 } 462 463 void tpm_gen_interrupt(struct tpm_chip *chip) 464 { 465 struct tpm_cmd_t tpm_cmd; 466 ssize_t rc; 467 468 tpm_cmd.header.in = tpm_getcap_header; 469 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP; 470 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4); 471 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT; 472 473 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 474 "attempting to determine the timeouts"); 475 } 476 EXPORT_SYMBOL_GPL(tpm_gen_interrupt); 477 478 #define TPM_ORD_STARTUP cpu_to_be32(153) 479 #define TPM_ST_CLEAR cpu_to_be16(1) 480 #define TPM_ST_STATE cpu_to_be16(2) 481 #define TPM_ST_DEACTIVATED cpu_to_be16(3) 482 static const struct tpm_input_header tpm_startup_header = { 483 .tag = TPM_TAG_RQU_COMMAND, 484 .length = cpu_to_be32(12), 485 .ordinal = TPM_ORD_STARTUP 486 }; 487 488 static int tpm_startup(struct tpm_chip *chip, __be16 startup_type) 489 { 490 struct tpm_cmd_t start_cmd; 491 start_cmd.header.in = tpm_startup_header; 492 493 start_cmd.params.startup_in.startup_type = startup_type; 494 return tpm_transmit_cmd(chip, &start_cmd, TPM_INTERNAL_RESULT_SIZE, 495 "attempting to start the TPM"); 496 } 497 498 int tpm_get_timeouts(struct tpm_chip *chip) 499 { 500 struct tpm_cmd_t tpm_cmd; 501 unsigned long new_timeout[4]; 502 unsigned long old_timeout[4]; 503 struct duration_t *duration_cap; 504 ssize_t rc; 505 506 if (chip->flags & TPM_CHIP_FLAG_TPM2) { 507 /* Fixed timeouts for TPM2 */ 508 chip->vendor.timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A); 509 chip->vendor.timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B); 510 chip->vendor.timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C); 511 chip->vendor.timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D); 512 chip->vendor.duration[TPM_SHORT] = 513 msecs_to_jiffies(TPM2_DURATION_SHORT); 514 chip->vendor.duration[TPM_MEDIUM] = 515 msecs_to_jiffies(TPM2_DURATION_MEDIUM); 516 chip->vendor.duration[TPM_LONG] = 517 msecs_to_jiffies(TPM2_DURATION_LONG); 518 return 0; 519 } 520 521 tpm_cmd.header.in = tpm_getcap_header; 522 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP; 523 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4); 524 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT; 525 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, NULL); 526 527 if (rc == TPM_ERR_INVALID_POSTINIT) { 528 /* The TPM is not started, we are the first to talk to it. 529 Execute a startup command. */ 530 dev_info(chip->pdev, "Issuing TPM_STARTUP"); 531 if (tpm_startup(chip, TPM_ST_CLEAR)) 532 return rc; 533 534 tpm_cmd.header.in = tpm_getcap_header; 535 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP; 536 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4); 537 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT; 538 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 539 NULL); 540 } 541 if (rc) { 542 dev_err(chip->pdev, 543 "A TPM error (%zd) occurred attempting to determine the timeouts\n", 544 rc); 545 goto duration; 546 } 547 548 if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 || 549 be32_to_cpu(tpm_cmd.header.out.length) 550 != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32)) 551 return -EINVAL; 552 553 old_timeout[0] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.a); 554 old_timeout[1] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.b); 555 old_timeout[2] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.c); 556 old_timeout[3] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.d); 557 memcpy(new_timeout, old_timeout, sizeof(new_timeout)); 558 559 /* 560 * Provide ability for vendor overrides of timeout values in case 561 * of misreporting. 562 */ 563 if (chip->ops->update_timeouts != NULL) 564 chip->vendor.timeout_adjusted = 565 chip->ops->update_timeouts(chip, new_timeout); 566 567 if (!chip->vendor.timeout_adjusted) { 568 /* Don't overwrite default if value is 0 */ 569 if (new_timeout[0] != 0 && new_timeout[0] < 1000) { 570 int i; 571 572 /* timeouts in msec rather usec */ 573 for (i = 0; i != ARRAY_SIZE(new_timeout); i++) 574 new_timeout[i] *= 1000; 575 chip->vendor.timeout_adjusted = true; 576 } 577 } 578 579 /* Report adjusted timeouts */ 580 if (chip->vendor.timeout_adjusted) { 581 dev_info(chip->pdev, 582 HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n", 583 old_timeout[0], new_timeout[0], 584 old_timeout[1], new_timeout[1], 585 old_timeout[2], new_timeout[2], 586 old_timeout[3], new_timeout[3]); 587 } 588 589 chip->vendor.timeout_a = usecs_to_jiffies(new_timeout[0]); 590 chip->vendor.timeout_b = usecs_to_jiffies(new_timeout[1]); 591 chip->vendor.timeout_c = usecs_to_jiffies(new_timeout[2]); 592 chip->vendor.timeout_d = usecs_to_jiffies(new_timeout[3]); 593 594 duration: 595 tpm_cmd.header.in = tpm_getcap_header; 596 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP; 597 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4); 598 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION; 599 600 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 601 "attempting to determine the durations"); 602 if (rc) 603 return rc; 604 605 if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 || 606 be32_to_cpu(tpm_cmd.header.out.length) 607 != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32)) 608 return -EINVAL; 609 610 duration_cap = &tpm_cmd.params.getcap_out.cap.duration; 611 chip->vendor.duration[TPM_SHORT] = 612 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short)); 613 chip->vendor.duration[TPM_MEDIUM] = 614 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium)); 615 chip->vendor.duration[TPM_LONG] = 616 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long)); 617 618 /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above 619 * value wrong and apparently reports msecs rather than usecs. So we 620 * fix up the resulting too-small TPM_SHORT value to make things work. 621 * We also scale the TPM_MEDIUM and -_LONG values by 1000. 622 */ 623 if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) { 624 chip->vendor.duration[TPM_SHORT] = HZ; 625 chip->vendor.duration[TPM_MEDIUM] *= 1000; 626 chip->vendor.duration[TPM_LONG] *= 1000; 627 chip->vendor.duration_adjusted = true; 628 dev_info(chip->pdev, "Adjusting TPM timeout parameters."); 629 } 630 return 0; 631 } 632 EXPORT_SYMBOL_GPL(tpm_get_timeouts); 633 634 #define TPM_ORD_CONTINUE_SELFTEST 83 635 #define CONTINUE_SELFTEST_RESULT_SIZE 10 636 637 static struct tpm_input_header continue_selftest_header = { 638 .tag = TPM_TAG_RQU_COMMAND, 639 .length = cpu_to_be32(10), 640 .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST), 641 }; 642 643 /** 644 * tpm_continue_selftest -- run TPM's selftest 645 * @chip: TPM chip to use 646 * 647 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing 648 * a TPM error code. 649 */ 650 static int tpm_continue_selftest(struct tpm_chip *chip) 651 { 652 int rc; 653 struct tpm_cmd_t cmd; 654 655 cmd.header.in = continue_selftest_header; 656 rc = tpm_transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE, 657 "continue selftest"); 658 return rc; 659 } 660 661 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21) 662 #define READ_PCR_RESULT_SIZE 30 663 static struct tpm_input_header pcrread_header = { 664 .tag = TPM_TAG_RQU_COMMAND, 665 .length = cpu_to_be32(14), 666 .ordinal = TPM_ORDINAL_PCRREAD 667 }; 668 669 int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) 670 { 671 int rc; 672 struct tpm_cmd_t cmd; 673 674 cmd.header.in = pcrread_header; 675 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx); 676 rc = tpm_transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE, 677 "attempting to read a pcr value"); 678 679 if (rc == 0) 680 memcpy(res_buf, cmd.params.pcrread_out.pcr_result, 681 TPM_DIGEST_SIZE); 682 return rc; 683 } 684 685 /** 686 * tpm_is_tpm2 - is the chip a TPM2 chip? 687 * @chip_num: tpm idx # or ANY 688 * 689 * Returns < 0 on error, and 1 or 0 on success depending whether the chip 690 * is a TPM2 chip. 691 */ 692 int tpm_is_tpm2(u32 chip_num) 693 { 694 struct tpm_chip *chip; 695 int rc; 696 697 chip = tpm_chip_find_get(chip_num); 698 if (chip == NULL) 699 return -ENODEV; 700 701 rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0; 702 703 tpm_chip_put(chip); 704 705 return rc; 706 } 707 EXPORT_SYMBOL_GPL(tpm_is_tpm2); 708 709 /** 710 * tpm_pcr_read - read a pcr value 711 * @chip_num: tpm idx # or ANY 712 * @pcr_idx: pcr idx to retrieve 713 * @res_buf: TPM_PCR value 714 * size of res_buf is 20 bytes (or NULL if you don't care) 715 * 716 * The TPM driver should be built-in, but for whatever reason it 717 * isn't, protect against the chip disappearing, by incrementing 718 * the module usage count. 719 */ 720 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf) 721 { 722 struct tpm_chip *chip; 723 int rc; 724 725 chip = tpm_chip_find_get(chip_num); 726 if (chip == NULL) 727 return -ENODEV; 728 if (chip->flags & TPM_CHIP_FLAG_TPM2) 729 rc = tpm2_pcr_read(chip, pcr_idx, res_buf); 730 else 731 rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf); 732 tpm_chip_put(chip); 733 return rc; 734 } 735 EXPORT_SYMBOL_GPL(tpm_pcr_read); 736 737 /** 738 * tpm_pcr_extend - extend pcr value with hash 739 * @chip_num: tpm idx # or AN& 740 * @pcr_idx: pcr idx to extend 741 * @hash: hash value used to extend pcr value 742 * 743 * The TPM driver should be built-in, but for whatever reason it 744 * isn't, protect against the chip disappearing, by incrementing 745 * the module usage count. 746 */ 747 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20) 748 #define EXTEND_PCR_RESULT_SIZE 34 749 static struct tpm_input_header pcrextend_header = { 750 .tag = TPM_TAG_RQU_COMMAND, 751 .length = cpu_to_be32(34), 752 .ordinal = TPM_ORD_PCR_EXTEND 753 }; 754 755 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash) 756 { 757 struct tpm_cmd_t cmd; 758 int rc; 759 struct tpm_chip *chip; 760 761 chip = tpm_chip_find_get(chip_num); 762 if (chip == NULL) 763 return -ENODEV; 764 765 if (chip->flags & TPM_CHIP_FLAG_TPM2) { 766 rc = tpm2_pcr_extend(chip, pcr_idx, hash); 767 tpm_chip_put(chip); 768 return rc; 769 } 770 771 cmd.header.in = pcrextend_header; 772 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx); 773 memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE); 774 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE, 775 "attempting extend a PCR value"); 776 777 tpm_chip_put(chip); 778 return rc; 779 } 780 EXPORT_SYMBOL_GPL(tpm_pcr_extend); 781 782 /** 783 * tpm_do_selftest - have the TPM continue its selftest and wait until it 784 * can receive further commands 785 * @chip: TPM chip to use 786 * 787 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing 788 * a TPM error code. 789 */ 790 int tpm_do_selftest(struct tpm_chip *chip) 791 { 792 int rc; 793 unsigned int loops; 794 unsigned int delay_msec = 100; 795 unsigned long duration; 796 struct tpm_cmd_t cmd; 797 798 duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST); 799 800 loops = jiffies_to_msecs(duration) / delay_msec; 801 802 rc = tpm_continue_selftest(chip); 803 /* This may fail if there was no TPM driver during a suspend/resume 804 * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST) 805 */ 806 if (rc) 807 return rc; 808 809 do { 810 /* Attempt to read a PCR value */ 811 cmd.header.in = pcrread_header; 812 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(0); 813 rc = tpm_transmit(chip, (u8 *) &cmd, READ_PCR_RESULT_SIZE); 814 /* Some buggy TPMs will not respond to tpm_tis_ready() for 815 * around 300ms while the self test is ongoing, keep trying 816 * until the self test duration expires. */ 817 if (rc == -ETIME) { 818 dev_info(chip->pdev, HW_ERR "TPM command timed out during continue self test"); 819 msleep(delay_msec); 820 continue; 821 } 822 823 if (rc < TPM_HEADER_SIZE) 824 return -EFAULT; 825 826 rc = be32_to_cpu(cmd.header.out.return_code); 827 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) { 828 dev_info(chip->pdev, 829 "TPM is disabled/deactivated (0x%X)\n", rc); 830 /* TPM is disabled and/or deactivated; driver can 831 * proceed and TPM does handle commands for 832 * suspend/resume correctly 833 */ 834 return 0; 835 } 836 if (rc != TPM_WARN_DOING_SELFTEST) 837 return rc; 838 msleep(delay_msec); 839 } while (--loops > 0); 840 841 return rc; 842 } 843 EXPORT_SYMBOL_GPL(tpm_do_selftest); 844 845 int tpm_send(u32 chip_num, void *cmd, size_t buflen) 846 { 847 struct tpm_chip *chip; 848 int rc; 849 850 chip = tpm_chip_find_get(chip_num); 851 if (chip == NULL) 852 return -ENODEV; 853 854 rc = tpm_transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd"); 855 856 tpm_chip_put(chip); 857 return rc; 858 } 859 EXPORT_SYMBOL_GPL(tpm_send); 860 861 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask, 862 bool check_cancel, bool *canceled) 863 { 864 u8 status = chip->ops->status(chip); 865 866 *canceled = false; 867 if ((status & mask) == mask) 868 return true; 869 if (check_cancel && chip->ops->req_canceled(chip, status)) { 870 *canceled = true; 871 return true; 872 } 873 return false; 874 } 875 876 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout, 877 wait_queue_head_t *queue, bool check_cancel) 878 { 879 unsigned long stop; 880 long rc; 881 u8 status; 882 bool canceled = false; 883 884 /* check current status */ 885 status = chip->ops->status(chip); 886 if ((status & mask) == mask) 887 return 0; 888 889 stop = jiffies + timeout; 890 891 if (chip->vendor.irq) { 892 again: 893 timeout = stop - jiffies; 894 if ((long)timeout <= 0) 895 return -ETIME; 896 rc = wait_event_interruptible_timeout(*queue, 897 wait_for_tpm_stat_cond(chip, mask, check_cancel, 898 &canceled), 899 timeout); 900 if (rc > 0) { 901 if (canceled) 902 return -ECANCELED; 903 return 0; 904 } 905 if (rc == -ERESTARTSYS && freezing(current)) { 906 clear_thread_flag(TIF_SIGPENDING); 907 goto again; 908 } 909 } else { 910 do { 911 msleep(TPM_TIMEOUT); 912 status = chip->ops->status(chip); 913 if ((status & mask) == mask) 914 return 0; 915 } while (time_before(jiffies, stop)); 916 } 917 return -ETIME; 918 } 919 EXPORT_SYMBOL_GPL(wait_for_tpm_stat); 920 921 #define TPM_ORD_SAVESTATE cpu_to_be32(152) 922 #define SAVESTATE_RESULT_SIZE 10 923 924 static struct tpm_input_header savestate_header = { 925 .tag = TPM_TAG_RQU_COMMAND, 926 .length = cpu_to_be32(10), 927 .ordinal = TPM_ORD_SAVESTATE 928 }; 929 930 /* 931 * We are about to suspend. Save the TPM state 932 * so that it can be restored. 933 */ 934 int tpm_pm_suspend(struct device *dev) 935 { 936 struct tpm_chip *chip = dev_get_drvdata(dev); 937 struct tpm_cmd_t cmd; 938 int rc, try; 939 940 u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 }; 941 942 if (chip == NULL) 943 return -ENODEV; 944 945 if (chip->flags & TPM_CHIP_FLAG_TPM2) { 946 tpm2_shutdown(chip, TPM2_SU_STATE); 947 return 0; 948 } 949 950 /* for buggy tpm, flush pcrs with extend to selected dummy */ 951 if (tpm_suspend_pcr) { 952 cmd.header.in = pcrextend_header; 953 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr); 954 memcpy(cmd.params.pcrextend_in.hash, dummy_hash, 955 TPM_DIGEST_SIZE); 956 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE, 957 "extending dummy pcr before suspend"); 958 } 959 960 /* now do the actual savestate */ 961 for (try = 0; try < TPM_RETRY; try++) { 962 cmd.header.in = savestate_header; 963 rc = tpm_transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, NULL); 964 965 /* 966 * If the TPM indicates that it is too busy to respond to 967 * this command then retry before giving up. It can take 968 * several seconds for this TPM to be ready. 969 * 970 * This can happen if the TPM has already been sent the 971 * SaveState command before the driver has loaded. TCG 1.2 972 * specification states that any communication after SaveState 973 * may cause the TPM to invalidate previously saved state. 974 */ 975 if (rc != TPM_WARN_RETRY) 976 break; 977 msleep(TPM_TIMEOUT_RETRY); 978 } 979 980 if (rc) 981 dev_err(chip->pdev, 982 "Error (%d) sending savestate before suspend\n", rc); 983 else if (try > 0) 984 dev_warn(chip->pdev, "TPM savestate took %dms\n", 985 try * TPM_TIMEOUT_RETRY); 986 987 return rc; 988 } 989 EXPORT_SYMBOL_GPL(tpm_pm_suspend); 990 991 /* 992 * Resume from a power safe. The BIOS already restored 993 * the TPM state. 994 */ 995 int tpm_pm_resume(struct device *dev) 996 { 997 struct tpm_chip *chip = dev_get_drvdata(dev); 998 999 if (chip == NULL) 1000 return -ENODEV; 1001 1002 return 0; 1003 } 1004 EXPORT_SYMBOL_GPL(tpm_pm_resume); 1005 1006 #define TPM_GETRANDOM_RESULT_SIZE 18 1007 static struct tpm_input_header tpm_getrandom_header = { 1008 .tag = TPM_TAG_RQU_COMMAND, 1009 .length = cpu_to_be32(14), 1010 .ordinal = TPM_ORD_GET_RANDOM 1011 }; 1012 1013 /** 1014 * tpm_get_random() - Get random bytes from the tpm's RNG 1015 * @chip_num: A specific chip number for the request or TPM_ANY_NUM 1016 * @out: destination buffer for the random bytes 1017 * @max: the max number of bytes to write to @out 1018 * 1019 * Returns < 0 on error and the number of bytes read on success 1020 */ 1021 int tpm_get_random(u32 chip_num, u8 *out, size_t max) 1022 { 1023 struct tpm_chip *chip; 1024 struct tpm_cmd_t tpm_cmd; 1025 u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA); 1026 int err, total = 0, retries = 5; 1027 u8 *dest = out; 1028 1029 if (!out || !num_bytes || max > TPM_MAX_RNG_DATA) 1030 return -EINVAL; 1031 1032 chip = tpm_chip_find_get(chip_num); 1033 if (chip == NULL) 1034 return -ENODEV; 1035 1036 if (chip->flags & TPM_CHIP_FLAG_TPM2) { 1037 err = tpm2_get_random(chip, out, max); 1038 tpm_chip_put(chip); 1039 return err; 1040 } 1041 1042 do { 1043 tpm_cmd.header.in = tpm_getrandom_header; 1044 tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes); 1045 1046 err = tpm_transmit_cmd(chip, &tpm_cmd, 1047 TPM_GETRANDOM_RESULT_SIZE + num_bytes, 1048 "attempting get random"); 1049 if (err) 1050 break; 1051 1052 recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len); 1053 memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd); 1054 1055 dest += recd; 1056 total += recd; 1057 num_bytes -= recd; 1058 } while (retries-- && total < max); 1059 1060 tpm_chip_put(chip); 1061 return total ? total : -EIO; 1062 } 1063 EXPORT_SYMBOL_GPL(tpm_get_random); 1064 1065 /** 1066 * tpm_seal_trusted() - seal a trusted key 1067 * @chip_num: A specific chip number for the request or TPM_ANY_NUM 1068 * @options: authentication values and other options 1069 * @payload: the key data in clear and encrypted form 1070 * 1071 * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips 1072 * are supported. 1073 */ 1074 int tpm_seal_trusted(u32 chip_num, struct trusted_key_payload *payload, 1075 struct trusted_key_options *options) 1076 { 1077 struct tpm_chip *chip; 1078 int rc; 1079 1080 chip = tpm_chip_find_get(chip_num); 1081 if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2)) 1082 return -ENODEV; 1083 1084 rc = tpm2_seal_trusted(chip, payload, options); 1085 1086 tpm_chip_put(chip); 1087 return rc; 1088 } 1089 EXPORT_SYMBOL_GPL(tpm_seal_trusted); 1090 1091 /** 1092 * tpm_unseal_trusted() - unseal a trusted key 1093 * @chip_num: A specific chip number for the request or TPM_ANY_NUM 1094 * @options: authentication values and other options 1095 * @payload: the key data in clear and encrypted form 1096 * 1097 * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips 1098 * are supported. 1099 */ 1100 int tpm_unseal_trusted(u32 chip_num, struct trusted_key_payload *payload, 1101 struct trusted_key_options *options) 1102 { 1103 struct tpm_chip *chip; 1104 int rc; 1105 1106 chip = tpm_chip_find_get(chip_num); 1107 if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2)) 1108 return -ENODEV; 1109 1110 rc = tpm2_unseal_trusted(chip, payload, options); 1111 1112 tpm_chip_put(chip); 1113 return rc; 1114 } 1115 EXPORT_SYMBOL_GPL(tpm_unseal_trusted); 1116 1117 static int __init tpm_init(void) 1118 { 1119 int rc; 1120 1121 tpm_class = class_create(THIS_MODULE, "tpm"); 1122 if (IS_ERR(tpm_class)) { 1123 pr_err("couldn't create tpm class\n"); 1124 return PTR_ERR(tpm_class); 1125 } 1126 1127 rc = alloc_chrdev_region(&tpm_devt, 0, TPM_NUM_DEVICES, "tpm"); 1128 if (rc < 0) { 1129 pr_err("tpm: failed to allocate char dev region\n"); 1130 class_destroy(tpm_class); 1131 return rc; 1132 } 1133 1134 return 0; 1135 } 1136 1137 static void __exit tpm_exit(void) 1138 { 1139 class_destroy(tpm_class); 1140 unregister_chrdev_region(tpm_devt, TPM_NUM_DEVICES); 1141 } 1142 1143 subsys_initcall(tpm_init); 1144 module_exit(tpm_exit); 1145 1146 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)"); 1147 MODULE_DESCRIPTION("TPM Driver"); 1148 MODULE_VERSION("2.0"); 1149 MODULE_LICENSE("GPL"); 1150