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 u8 category = (ordinal >> 24) & 0xFF; 314 315 if ((category == TPM_PROTECTED_COMMAND && ordinal < TPM_MAX_ORDINAL) || 316 (category == TPM_CONNECTION_COMMAND && ordinal < TSC_MAX_ORDINAL)) 317 duration_idx = tpm_ordinal_duration[ordinal]; 318 319 if (duration_idx != TPM_UNDEFINED) 320 duration = chip->vendor.duration[duration_idx]; 321 if (duration <= 0) 322 return 2 * 60 * HZ; 323 else 324 return duration; 325 } 326 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration); 327 328 /* 329 * Internal kernel interface to transmit TPM commands 330 */ 331 ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf, 332 size_t bufsiz) 333 { 334 ssize_t rc; 335 u32 count, ordinal; 336 unsigned long stop; 337 338 if (bufsiz > TPM_BUFSIZE) 339 bufsiz = TPM_BUFSIZE; 340 341 count = be32_to_cpu(*((__be32 *) (buf + 2))); 342 ordinal = be32_to_cpu(*((__be32 *) (buf + 6))); 343 if (count == 0) 344 return -ENODATA; 345 if (count > bufsiz) { 346 dev_err(chip->pdev, 347 "invalid count value %x %zx\n", count, bufsiz); 348 return -E2BIG; 349 } 350 351 mutex_lock(&chip->tpm_mutex); 352 353 rc = chip->ops->send(chip, (u8 *) buf, count); 354 if (rc < 0) { 355 dev_err(chip->pdev, 356 "tpm_transmit: tpm_send: error %zd\n", rc); 357 goto out; 358 } 359 360 if (chip->vendor.irq) 361 goto out_recv; 362 363 if (chip->flags & TPM_CHIP_FLAG_TPM2) 364 stop = jiffies + tpm2_calc_ordinal_duration(chip, ordinal); 365 else 366 stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal); 367 do { 368 u8 status = chip->ops->status(chip); 369 if ((status & chip->ops->req_complete_mask) == 370 chip->ops->req_complete_val) 371 goto out_recv; 372 373 if (chip->ops->req_canceled(chip, status)) { 374 dev_err(chip->pdev, "Operation Canceled\n"); 375 rc = -ECANCELED; 376 goto out; 377 } 378 379 msleep(TPM_TIMEOUT); /* CHECK */ 380 rmb(); 381 } while (time_before(jiffies, stop)); 382 383 chip->ops->cancel(chip); 384 dev_err(chip->pdev, "Operation Timed out\n"); 385 rc = -ETIME; 386 goto out; 387 388 out_recv: 389 rc = chip->ops->recv(chip, (u8 *) buf, bufsiz); 390 if (rc < 0) 391 dev_err(chip->pdev, 392 "tpm_transmit: tpm_recv: error %zd\n", rc); 393 out: 394 mutex_unlock(&chip->tpm_mutex); 395 return rc; 396 } 397 398 #define TPM_DIGEST_SIZE 20 399 #define TPM_RET_CODE_IDX 6 400 401 ssize_t tpm_transmit_cmd(struct tpm_chip *chip, void *cmd, 402 int len, const char *desc) 403 { 404 struct tpm_output_header *header; 405 int err; 406 407 len = tpm_transmit(chip, (u8 *) cmd, len); 408 if (len < 0) 409 return len; 410 else if (len < TPM_HEADER_SIZE) 411 return -EFAULT; 412 413 header = cmd; 414 415 err = be32_to_cpu(header->return_code); 416 if (err != 0 && desc) 417 dev_err(chip->pdev, "A TPM error (%d) occurred %s\n", err, 418 desc); 419 420 return err; 421 } 422 423 #define TPM_INTERNAL_RESULT_SIZE 200 424 #define TPM_ORD_GET_CAP cpu_to_be32(101) 425 #define TPM_ORD_GET_RANDOM cpu_to_be32(70) 426 427 static const struct tpm_input_header tpm_getcap_header = { 428 .tag = TPM_TAG_RQU_COMMAND, 429 .length = cpu_to_be32(22), 430 .ordinal = TPM_ORD_GET_CAP 431 }; 432 433 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap, 434 const char *desc) 435 { 436 struct tpm_cmd_t tpm_cmd; 437 int rc; 438 struct tpm_chip *chip = dev_get_drvdata(dev); 439 440 tpm_cmd.header.in = tpm_getcap_header; 441 if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) { 442 tpm_cmd.params.getcap_in.cap = subcap_id; 443 /*subcap field not necessary */ 444 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0); 445 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32)); 446 } else { 447 if (subcap_id == TPM_CAP_FLAG_PERM || 448 subcap_id == TPM_CAP_FLAG_VOL) 449 tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG; 450 else 451 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP; 452 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4); 453 tpm_cmd.params.getcap_in.subcap = subcap_id; 454 } 455 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc); 456 if (!rc) 457 *cap = tpm_cmd.params.getcap_out.cap; 458 return rc; 459 } 460 461 void tpm_gen_interrupt(struct tpm_chip *chip) 462 { 463 struct tpm_cmd_t tpm_cmd; 464 ssize_t rc; 465 466 tpm_cmd.header.in = tpm_getcap_header; 467 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP; 468 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4); 469 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT; 470 471 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 472 "attempting to determine the timeouts"); 473 } 474 EXPORT_SYMBOL_GPL(tpm_gen_interrupt); 475 476 #define TPM_ORD_STARTUP cpu_to_be32(153) 477 #define TPM_ST_CLEAR cpu_to_be16(1) 478 #define TPM_ST_STATE cpu_to_be16(2) 479 #define TPM_ST_DEACTIVATED cpu_to_be16(3) 480 static const struct tpm_input_header tpm_startup_header = { 481 .tag = TPM_TAG_RQU_COMMAND, 482 .length = cpu_to_be32(12), 483 .ordinal = TPM_ORD_STARTUP 484 }; 485 486 static int tpm_startup(struct tpm_chip *chip, __be16 startup_type) 487 { 488 struct tpm_cmd_t start_cmd; 489 start_cmd.header.in = tpm_startup_header; 490 491 start_cmd.params.startup_in.startup_type = startup_type; 492 return tpm_transmit_cmd(chip, &start_cmd, TPM_INTERNAL_RESULT_SIZE, 493 "attempting to start the TPM"); 494 } 495 496 int tpm_get_timeouts(struct tpm_chip *chip) 497 { 498 struct tpm_cmd_t tpm_cmd; 499 unsigned long new_timeout[4]; 500 unsigned long old_timeout[4]; 501 struct duration_t *duration_cap; 502 ssize_t rc; 503 504 tpm_cmd.header.in = tpm_getcap_header; 505 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP; 506 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4); 507 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT; 508 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, NULL); 509 510 if (rc == TPM_ERR_INVALID_POSTINIT) { 511 /* The TPM is not started, we are the first to talk to it. 512 Execute a startup command. */ 513 dev_info(chip->pdev, "Issuing TPM_STARTUP"); 514 if (tpm_startup(chip, TPM_ST_CLEAR)) 515 return rc; 516 517 tpm_cmd.header.in = tpm_getcap_header; 518 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP; 519 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4); 520 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT; 521 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 522 NULL); 523 } 524 if (rc) { 525 dev_err(chip->pdev, 526 "A TPM error (%zd) occurred attempting to determine the timeouts\n", 527 rc); 528 goto duration; 529 } 530 531 if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 || 532 be32_to_cpu(tpm_cmd.header.out.length) 533 != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32)) 534 return -EINVAL; 535 536 old_timeout[0] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.a); 537 old_timeout[1] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.b); 538 old_timeout[2] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.c); 539 old_timeout[3] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.d); 540 memcpy(new_timeout, old_timeout, sizeof(new_timeout)); 541 542 /* 543 * Provide ability for vendor overrides of timeout values in case 544 * of misreporting. 545 */ 546 if (chip->ops->update_timeouts != NULL) 547 chip->vendor.timeout_adjusted = 548 chip->ops->update_timeouts(chip, new_timeout); 549 550 if (!chip->vendor.timeout_adjusted) { 551 /* Don't overwrite default if value is 0 */ 552 if (new_timeout[0] != 0 && new_timeout[0] < 1000) { 553 int i; 554 555 /* timeouts in msec rather usec */ 556 for (i = 0; i != ARRAY_SIZE(new_timeout); i++) 557 new_timeout[i] *= 1000; 558 chip->vendor.timeout_adjusted = true; 559 } 560 } 561 562 /* Report adjusted timeouts */ 563 if (chip->vendor.timeout_adjusted) { 564 dev_info(chip->pdev, 565 HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n", 566 old_timeout[0], new_timeout[0], 567 old_timeout[1], new_timeout[1], 568 old_timeout[2], new_timeout[2], 569 old_timeout[3], new_timeout[3]); 570 } 571 572 chip->vendor.timeout_a = usecs_to_jiffies(new_timeout[0]); 573 chip->vendor.timeout_b = usecs_to_jiffies(new_timeout[1]); 574 chip->vendor.timeout_c = usecs_to_jiffies(new_timeout[2]); 575 chip->vendor.timeout_d = usecs_to_jiffies(new_timeout[3]); 576 577 duration: 578 tpm_cmd.header.in = tpm_getcap_header; 579 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP; 580 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4); 581 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION; 582 583 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 584 "attempting to determine the durations"); 585 if (rc) 586 return rc; 587 588 if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 || 589 be32_to_cpu(tpm_cmd.header.out.length) 590 != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32)) 591 return -EINVAL; 592 593 duration_cap = &tpm_cmd.params.getcap_out.cap.duration; 594 chip->vendor.duration[TPM_SHORT] = 595 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short)); 596 chip->vendor.duration[TPM_MEDIUM] = 597 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium)); 598 chip->vendor.duration[TPM_LONG] = 599 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long)); 600 601 /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above 602 * value wrong and apparently reports msecs rather than usecs. So we 603 * fix up the resulting too-small TPM_SHORT value to make things work. 604 * We also scale the TPM_MEDIUM and -_LONG values by 1000. 605 */ 606 if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) { 607 chip->vendor.duration[TPM_SHORT] = HZ; 608 chip->vendor.duration[TPM_MEDIUM] *= 1000; 609 chip->vendor.duration[TPM_LONG] *= 1000; 610 chip->vendor.duration_adjusted = true; 611 dev_info(chip->pdev, "Adjusting TPM timeout parameters."); 612 } 613 return 0; 614 } 615 EXPORT_SYMBOL_GPL(tpm_get_timeouts); 616 617 #define TPM_ORD_CONTINUE_SELFTEST 83 618 #define CONTINUE_SELFTEST_RESULT_SIZE 10 619 620 static struct tpm_input_header continue_selftest_header = { 621 .tag = TPM_TAG_RQU_COMMAND, 622 .length = cpu_to_be32(10), 623 .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST), 624 }; 625 626 /** 627 * tpm_continue_selftest -- run TPM's selftest 628 * @chip: TPM chip to use 629 * 630 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing 631 * a TPM error code. 632 */ 633 static int tpm_continue_selftest(struct tpm_chip *chip) 634 { 635 int rc; 636 struct tpm_cmd_t cmd; 637 638 cmd.header.in = continue_selftest_header; 639 rc = tpm_transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE, 640 "continue selftest"); 641 return rc; 642 } 643 644 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21) 645 #define READ_PCR_RESULT_SIZE 30 646 static struct tpm_input_header pcrread_header = { 647 .tag = TPM_TAG_RQU_COMMAND, 648 .length = cpu_to_be32(14), 649 .ordinal = TPM_ORDINAL_PCRREAD 650 }; 651 652 int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) 653 { 654 int rc; 655 struct tpm_cmd_t cmd; 656 657 cmd.header.in = pcrread_header; 658 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx); 659 rc = tpm_transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE, 660 "attempting to read a pcr value"); 661 662 if (rc == 0) 663 memcpy(res_buf, cmd.params.pcrread_out.pcr_result, 664 TPM_DIGEST_SIZE); 665 return rc; 666 } 667 668 /** 669 * tpm_pcr_read - read a pcr value 670 * @chip_num: tpm idx # or ANY 671 * @pcr_idx: pcr idx to retrieve 672 * @res_buf: TPM_PCR value 673 * size of res_buf is 20 bytes (or NULL if you don't care) 674 * 675 * The TPM driver should be built-in, but for whatever reason it 676 * isn't, protect against the chip disappearing, by incrementing 677 * the module usage count. 678 */ 679 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf) 680 { 681 struct tpm_chip *chip; 682 int rc; 683 684 chip = tpm_chip_find_get(chip_num); 685 if (chip == NULL) 686 return -ENODEV; 687 if (chip->flags & TPM_CHIP_FLAG_TPM2) 688 rc = tpm2_pcr_read(chip, pcr_idx, res_buf); 689 else 690 rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf); 691 tpm_chip_put(chip); 692 return rc; 693 } 694 EXPORT_SYMBOL_GPL(tpm_pcr_read); 695 696 /** 697 * tpm_pcr_extend - extend pcr value with hash 698 * @chip_num: tpm idx # or AN& 699 * @pcr_idx: pcr idx to extend 700 * @hash: hash value used to extend pcr value 701 * 702 * The TPM driver should be built-in, but for whatever reason it 703 * isn't, protect against the chip disappearing, by incrementing 704 * the module usage count. 705 */ 706 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20) 707 #define EXTEND_PCR_RESULT_SIZE 34 708 static struct tpm_input_header pcrextend_header = { 709 .tag = TPM_TAG_RQU_COMMAND, 710 .length = cpu_to_be32(34), 711 .ordinal = TPM_ORD_PCR_EXTEND 712 }; 713 714 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash) 715 { 716 struct tpm_cmd_t cmd; 717 int rc; 718 struct tpm_chip *chip; 719 720 chip = tpm_chip_find_get(chip_num); 721 if (chip == NULL) 722 return -ENODEV; 723 724 if (chip->flags & TPM_CHIP_FLAG_TPM2) { 725 rc = tpm2_pcr_extend(chip, pcr_idx, hash); 726 tpm_chip_put(chip); 727 return rc; 728 } 729 730 cmd.header.in = pcrextend_header; 731 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx); 732 memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE); 733 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE, 734 "attempting extend a PCR value"); 735 736 tpm_chip_put(chip); 737 return rc; 738 } 739 EXPORT_SYMBOL_GPL(tpm_pcr_extend); 740 741 /** 742 * tpm_do_selftest - have the TPM continue its selftest and wait until it 743 * can receive further commands 744 * @chip: TPM chip to use 745 * 746 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing 747 * a TPM error code. 748 */ 749 int tpm_do_selftest(struct tpm_chip *chip) 750 { 751 int rc; 752 unsigned int loops; 753 unsigned int delay_msec = 100; 754 unsigned long duration; 755 struct tpm_cmd_t cmd; 756 757 duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST); 758 759 loops = jiffies_to_msecs(duration) / delay_msec; 760 761 rc = tpm_continue_selftest(chip); 762 /* This may fail if there was no TPM driver during a suspend/resume 763 * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST) 764 */ 765 if (rc) 766 return rc; 767 768 do { 769 /* Attempt to read a PCR value */ 770 cmd.header.in = pcrread_header; 771 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(0); 772 rc = tpm_transmit(chip, (u8 *) &cmd, READ_PCR_RESULT_SIZE); 773 /* Some buggy TPMs will not respond to tpm_tis_ready() for 774 * around 300ms while the self test is ongoing, keep trying 775 * until the self test duration expires. */ 776 if (rc == -ETIME) { 777 dev_info(chip->pdev, HW_ERR "TPM command timed out during continue self test"); 778 msleep(delay_msec); 779 continue; 780 } 781 782 if (rc < TPM_HEADER_SIZE) 783 return -EFAULT; 784 785 rc = be32_to_cpu(cmd.header.out.return_code); 786 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) { 787 dev_info(chip->pdev, 788 "TPM is disabled/deactivated (0x%X)\n", rc); 789 /* TPM is disabled and/or deactivated; driver can 790 * proceed and TPM does handle commands for 791 * suspend/resume correctly 792 */ 793 return 0; 794 } 795 if (rc != TPM_WARN_DOING_SELFTEST) 796 return rc; 797 msleep(delay_msec); 798 } while (--loops > 0); 799 800 return rc; 801 } 802 EXPORT_SYMBOL_GPL(tpm_do_selftest); 803 804 int tpm_send(u32 chip_num, void *cmd, size_t buflen) 805 { 806 struct tpm_chip *chip; 807 int rc; 808 809 chip = tpm_chip_find_get(chip_num); 810 if (chip == NULL) 811 return -ENODEV; 812 813 rc = tpm_transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd"); 814 815 tpm_chip_put(chip); 816 return rc; 817 } 818 EXPORT_SYMBOL_GPL(tpm_send); 819 820 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask, 821 bool check_cancel, bool *canceled) 822 { 823 u8 status = chip->ops->status(chip); 824 825 *canceled = false; 826 if ((status & mask) == mask) 827 return true; 828 if (check_cancel && chip->ops->req_canceled(chip, status)) { 829 *canceled = true; 830 return true; 831 } 832 return false; 833 } 834 835 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout, 836 wait_queue_head_t *queue, bool check_cancel) 837 { 838 unsigned long stop; 839 long rc; 840 u8 status; 841 bool canceled = false; 842 843 /* check current status */ 844 status = chip->ops->status(chip); 845 if ((status & mask) == mask) 846 return 0; 847 848 stop = jiffies + timeout; 849 850 if (chip->vendor.irq) { 851 again: 852 timeout = stop - jiffies; 853 if ((long)timeout <= 0) 854 return -ETIME; 855 rc = wait_event_interruptible_timeout(*queue, 856 wait_for_tpm_stat_cond(chip, mask, check_cancel, 857 &canceled), 858 timeout); 859 if (rc > 0) { 860 if (canceled) 861 return -ECANCELED; 862 return 0; 863 } 864 if (rc == -ERESTARTSYS && freezing(current)) { 865 clear_thread_flag(TIF_SIGPENDING); 866 goto again; 867 } 868 } else { 869 do { 870 msleep(TPM_TIMEOUT); 871 status = chip->ops->status(chip); 872 if ((status & mask) == mask) 873 return 0; 874 } while (time_before(jiffies, stop)); 875 } 876 return -ETIME; 877 } 878 EXPORT_SYMBOL_GPL(wait_for_tpm_stat); 879 880 #define TPM_ORD_SAVESTATE cpu_to_be32(152) 881 #define SAVESTATE_RESULT_SIZE 10 882 883 static struct tpm_input_header savestate_header = { 884 .tag = TPM_TAG_RQU_COMMAND, 885 .length = cpu_to_be32(10), 886 .ordinal = TPM_ORD_SAVESTATE 887 }; 888 889 /* 890 * We are about to suspend. Save the TPM state 891 * so that it can be restored. 892 */ 893 int tpm_pm_suspend(struct device *dev) 894 { 895 struct tpm_chip *chip = dev_get_drvdata(dev); 896 struct tpm_cmd_t cmd; 897 int rc, try; 898 899 u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 }; 900 901 if (chip == NULL) 902 return -ENODEV; 903 904 if (chip->flags & TPM_CHIP_FLAG_TPM2) { 905 tpm2_shutdown(chip, TPM2_SU_STATE); 906 return 0; 907 } 908 909 /* for buggy tpm, flush pcrs with extend to selected dummy */ 910 if (tpm_suspend_pcr) { 911 cmd.header.in = pcrextend_header; 912 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr); 913 memcpy(cmd.params.pcrextend_in.hash, dummy_hash, 914 TPM_DIGEST_SIZE); 915 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE, 916 "extending dummy pcr before suspend"); 917 } 918 919 /* now do the actual savestate */ 920 for (try = 0; try < TPM_RETRY; try++) { 921 cmd.header.in = savestate_header; 922 rc = tpm_transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, NULL); 923 924 /* 925 * If the TPM indicates that it is too busy to respond to 926 * this command then retry before giving up. It can take 927 * several seconds for this TPM to be ready. 928 * 929 * This can happen if the TPM has already been sent the 930 * SaveState command before the driver has loaded. TCG 1.2 931 * specification states that any communication after SaveState 932 * may cause the TPM to invalidate previously saved state. 933 */ 934 if (rc != TPM_WARN_RETRY) 935 break; 936 msleep(TPM_TIMEOUT_RETRY); 937 } 938 939 if (rc) 940 dev_err(chip->pdev, 941 "Error (%d) sending savestate before suspend\n", rc); 942 else if (try > 0) 943 dev_warn(chip->pdev, "TPM savestate took %dms\n", 944 try * TPM_TIMEOUT_RETRY); 945 946 return rc; 947 } 948 EXPORT_SYMBOL_GPL(tpm_pm_suspend); 949 950 /* 951 * Resume from a power safe. The BIOS already restored 952 * the TPM state. 953 */ 954 int tpm_pm_resume(struct device *dev) 955 { 956 struct tpm_chip *chip = dev_get_drvdata(dev); 957 958 if (chip == NULL) 959 return -ENODEV; 960 961 return 0; 962 } 963 EXPORT_SYMBOL_GPL(tpm_pm_resume); 964 965 #define TPM_GETRANDOM_RESULT_SIZE 18 966 static struct tpm_input_header tpm_getrandom_header = { 967 .tag = TPM_TAG_RQU_COMMAND, 968 .length = cpu_to_be32(14), 969 .ordinal = TPM_ORD_GET_RANDOM 970 }; 971 972 /** 973 * tpm_get_random() - Get random bytes from the tpm's RNG 974 * @chip_num: A specific chip number for the request or TPM_ANY_NUM 975 * @out: destination buffer for the random bytes 976 * @max: the max number of bytes to write to @out 977 * 978 * Returns < 0 on error and the number of bytes read on success 979 */ 980 int tpm_get_random(u32 chip_num, u8 *out, size_t max) 981 { 982 struct tpm_chip *chip; 983 struct tpm_cmd_t tpm_cmd; 984 u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA); 985 int err, total = 0, retries = 5; 986 u8 *dest = out; 987 988 if (!out || !num_bytes || max > TPM_MAX_RNG_DATA) 989 return -EINVAL; 990 991 chip = tpm_chip_find_get(chip_num); 992 if (chip == NULL) 993 return -ENODEV; 994 995 if (chip->flags & TPM_CHIP_FLAG_TPM2) { 996 err = tpm2_get_random(chip, out, max); 997 tpm_chip_put(chip); 998 return err; 999 } 1000 1001 do { 1002 tpm_cmd.header.in = tpm_getrandom_header; 1003 tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes); 1004 1005 err = tpm_transmit_cmd(chip, &tpm_cmd, 1006 TPM_GETRANDOM_RESULT_SIZE + num_bytes, 1007 "attempting get random"); 1008 if (err) 1009 break; 1010 1011 recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len); 1012 memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd); 1013 1014 dest += recd; 1015 total += recd; 1016 num_bytes -= recd; 1017 } while (retries-- && total < max); 1018 1019 tpm_chip_put(chip); 1020 return total ? total : -EIO; 1021 } 1022 EXPORT_SYMBOL_GPL(tpm_get_random); 1023 1024 static int __init tpm_init(void) 1025 { 1026 int rc; 1027 1028 tpm_class = class_create(THIS_MODULE, "tpm"); 1029 if (IS_ERR(tpm_class)) { 1030 pr_err("couldn't create tpm class\n"); 1031 return PTR_ERR(tpm_class); 1032 } 1033 1034 rc = alloc_chrdev_region(&tpm_devt, 0, TPM_NUM_DEVICES, "tpm"); 1035 if (rc < 0) { 1036 pr_err("tpm: failed to allocate char dev region\n"); 1037 class_destroy(tpm_class); 1038 return rc; 1039 } 1040 1041 return 0; 1042 } 1043 1044 static void __exit tpm_exit(void) 1045 { 1046 class_destroy(tpm_class); 1047 unregister_chrdev_region(tpm_devt, TPM_NUM_DEVICES); 1048 } 1049 1050 subsys_initcall(tpm_init); 1051 module_exit(tpm_exit); 1052 1053 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)"); 1054 MODULE_DESCRIPTION("TPM Driver"); 1055 MODULE_VERSION("2.0"); 1056 MODULE_LICENSE("GPL"); 1057