2 * Copyright (C) 2004 IBM Corporation
3 * Copyright (C) 2014 Intel Corporation
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>
11 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
13 * Device driver for TCG/TCPA TPM (trusted platform module).
14 * Specifications at www.trustedcomputinggroup.org
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
21 * Note, the TPM chip is not interrupt driven (only polling)
22 * and can have very long timeouts (minutes!). Hence the unusual
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>
34 #include "tpm_eventlog.h"
36 #define TPM_MAX_ORDINAL 243
37 #define TSC_MAX_ORDINAL 12
38 #define TPM_PROTECTED_COMMAND 0x00
39 #define TPM_CONNECTION_COMMAND 0x40
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.
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.");
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.
59 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
60 TPM_UNDEFINED, /* 0 */
65 TPM_UNDEFINED, /* 5 */
115 TPM_UNDEFINED, /* 55 */
135 TPM_UNDEFINED, /* 75 */
145 TPM_UNDEFINED, /* 85 */
155 TPM_UNDEFINED, /* 95 */
160 TPM_MEDIUM, /* 100 */
165 TPM_UNDEFINED, /* 105 */
195 TPM_UNDEFINED, /* 135 */
205 TPM_UNDEFINED, /* 145 */
215 TPM_UNDEFINED, /* 155 */
225 TPM_UNDEFINED, /* 165 */
235 TPM_UNDEFINED, /* 175 */
240 TPM_MEDIUM, /* 180 */
245 TPM_MEDIUM, /* 185 */
250 TPM_UNDEFINED, /* 190 */
255 TPM_UNDEFINED, /* 195 */
270 TPM_MEDIUM, /* 210 */
275 TPM_UNDEFINED, /* 215 */
285 TPM_UNDEFINED, /* 225 */
295 TPM_UNDEFINED, /* 235 */
306 * Returns max number of jiffies to wait
308 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
311 int duration_idx = TPM_UNDEFINED;
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.
318 if (ordinal < TPM_MAX_ORDINAL)
319 duration_idx = tpm_ordinal_duration[ordinal];
321 if (duration_idx != TPM_UNDEFINED)
322 duration = chip->duration[duration_idx];
328 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
331 * Internal kernel interface to transmit TPM commands
333 ssize_t tpm_transmit(struct tpm_chip *chip, const u8 *buf, size_t bufsiz,
340 if (bufsiz < TPM_HEADER_SIZE)
343 if (bufsiz > TPM_BUFSIZE)
344 bufsiz = TPM_BUFSIZE;
346 count = be32_to_cpu(*((__be32 *) (buf + 2)));
347 ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
350 if (count > bufsiz) {
352 "invalid count value %x %zx\n", count, bufsiz);
356 if (!(flags & TPM_TRANSMIT_UNLOCKED))
357 mutex_lock(&chip->tpm_mutex);
359 rc = chip->ops->send(chip, (u8 *) buf, count);
362 "tpm_transmit: tpm_send: error %zd\n", rc);
366 if (chip->flags & TPM_CHIP_FLAG_IRQ)
369 if (chip->flags & TPM_CHIP_FLAG_TPM2)
370 stop = jiffies + tpm2_calc_ordinal_duration(chip, ordinal);
372 stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
374 u8 status = chip->ops->status(chip);
375 if ((status & chip->ops->req_complete_mask) ==
376 chip->ops->req_complete_val)
379 if (chip->ops->req_canceled(chip, status)) {
380 dev_err(&chip->dev, "Operation Canceled\n");
385 msleep(TPM_TIMEOUT); /* CHECK */
387 } while (time_before(jiffies, stop));
389 chip->ops->cancel(chip);
390 dev_err(&chip->dev, "Operation Timed out\n");
395 rc = chip->ops->recv(chip, (u8 *) buf, bufsiz);
398 "tpm_transmit: tpm_recv: error %zd\n", rc);
400 if (!(flags & TPM_TRANSMIT_UNLOCKED))
401 mutex_unlock(&chip->tpm_mutex);
405 #define TPM_DIGEST_SIZE 20
406 #define TPM_RET_CODE_IDX 6
408 ssize_t tpm_transmit_cmd(struct tpm_chip *chip, const void *cmd,
409 int len, unsigned int flags, const char *desc)
411 const struct tpm_output_header *header;
414 len = tpm_transmit(chip, (const u8 *)cmd, len, flags);
417 else if (len < TPM_HEADER_SIZE)
422 err = be32_to_cpu(header->return_code);
423 if (err != 0 && err != TPM_ERR_DISABLED && err != TPM_ERR_DEACTIVATED
425 dev_err(&chip->dev, "A TPM error (%d) occurred %s\n", err,
431 #define TPM_INTERNAL_RESULT_SIZE 200
432 #define TPM_ORD_GET_CAP cpu_to_be32(101)
433 #define TPM_ORD_GET_RANDOM cpu_to_be32(70)
435 static const struct tpm_input_header tpm_getcap_header = {
436 .tag = TPM_TAG_RQU_COMMAND,
437 .length = cpu_to_be32(22),
438 .ordinal = TPM_ORD_GET_CAP
441 ssize_t tpm_getcap(struct tpm_chip *chip, __be32 subcap_id, cap_t *cap,
444 struct tpm_cmd_t tpm_cmd;
447 tpm_cmd.header.in = tpm_getcap_header;
448 if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
449 tpm_cmd.params.getcap_in.cap = subcap_id;
450 /*subcap field not necessary */
451 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
452 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
454 if (subcap_id == TPM_CAP_FLAG_PERM ||
455 subcap_id == TPM_CAP_FLAG_VOL)
456 tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
458 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
459 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
460 tpm_cmd.params.getcap_in.subcap = subcap_id;
462 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 0,
465 *cap = tpm_cmd.params.getcap_out.cap;
468 EXPORT_SYMBOL_GPL(tpm_getcap);
470 #define TPM_ORD_STARTUP cpu_to_be32(153)
471 #define TPM_ST_CLEAR cpu_to_be16(1)
472 #define TPM_ST_STATE cpu_to_be16(2)
473 #define TPM_ST_DEACTIVATED cpu_to_be16(3)
474 static const struct tpm_input_header tpm_startup_header = {
475 .tag = TPM_TAG_RQU_COMMAND,
476 .length = cpu_to_be32(12),
477 .ordinal = TPM_ORD_STARTUP
480 static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
482 struct tpm_cmd_t start_cmd;
483 start_cmd.header.in = tpm_startup_header;
485 start_cmd.params.startup_in.startup_type = startup_type;
486 return tpm_transmit_cmd(chip, &start_cmd, TPM_INTERNAL_RESULT_SIZE, 0,
487 "attempting to start the TPM");
490 int tpm_get_timeouts(struct tpm_chip *chip)
492 struct tpm_cmd_t tpm_cmd;
493 unsigned long timeout_old[4], timeout_chip[4], timeout_eff[4];
494 struct duration_t *duration_cap;
497 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
498 /* Fixed timeouts for TPM2 */
499 chip->timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
500 chip->timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
501 chip->timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
502 chip->timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
503 chip->duration[TPM_SHORT] =
504 msecs_to_jiffies(TPM2_DURATION_SHORT);
505 chip->duration[TPM_MEDIUM] =
506 msecs_to_jiffies(TPM2_DURATION_MEDIUM);
507 chip->duration[TPM_LONG] =
508 msecs_to_jiffies(TPM2_DURATION_LONG);
512 tpm_cmd.header.in = tpm_getcap_header;
513 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
514 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
515 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
516 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 0,
519 if (rc == TPM_ERR_INVALID_POSTINIT) {
520 /* The TPM is not started, we are the first to talk to it.
521 Execute a startup command. */
522 dev_info(&chip->dev, "Issuing TPM_STARTUP");
523 if (tpm_startup(chip, TPM_ST_CLEAR))
526 tpm_cmd.header.in = tpm_getcap_header;
527 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
528 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
529 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
530 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
535 "A TPM error (%zd) occurred attempting to determine the timeouts\n",
540 if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
541 be32_to_cpu(tpm_cmd.header.out.length)
542 != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
545 timeout_old[0] = jiffies_to_usecs(chip->timeout_a);
546 timeout_old[1] = jiffies_to_usecs(chip->timeout_b);
547 timeout_old[2] = jiffies_to_usecs(chip->timeout_c);
548 timeout_old[3] = jiffies_to_usecs(chip->timeout_d);
549 timeout_chip[0] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.a);
550 timeout_chip[1] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.b);
551 timeout_chip[2] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.c);
552 timeout_chip[3] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.d);
553 memcpy(timeout_eff, timeout_chip, sizeof(timeout_eff));
556 * Provide ability for vendor overrides of timeout values in case
559 if (chip->ops->update_timeouts != NULL)
560 chip->timeout_adjusted =
561 chip->ops->update_timeouts(chip, timeout_eff);
563 if (!chip->timeout_adjusted) {
564 /* Restore default if chip reported 0 */
567 for (i = 0; i < ARRAY_SIZE(timeout_eff); i++) {
571 timeout_eff[i] = timeout_old[i];
572 chip->timeout_adjusted = true;
575 if (timeout_eff[0] != 0 && timeout_eff[0] < 1000) {
576 /* timeouts in msec rather usec */
577 for (i = 0; i != ARRAY_SIZE(timeout_eff); i++)
578 timeout_eff[i] *= 1000;
579 chip->timeout_adjusted = true;
583 /* Report adjusted timeouts */
584 if (chip->timeout_adjusted) {
586 HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n",
587 timeout_chip[0], timeout_eff[0],
588 timeout_chip[1], timeout_eff[1],
589 timeout_chip[2], timeout_eff[2],
590 timeout_chip[3], timeout_eff[3]);
593 chip->timeout_a = usecs_to_jiffies(timeout_eff[0]);
594 chip->timeout_b = usecs_to_jiffies(timeout_eff[1]);
595 chip->timeout_c = usecs_to_jiffies(timeout_eff[2]);
596 chip->timeout_d = usecs_to_jiffies(timeout_eff[3]);
599 tpm_cmd.header.in = tpm_getcap_header;
600 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
601 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
602 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
604 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 0,
605 "attempting to determine the durations");
609 if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
610 be32_to_cpu(tpm_cmd.header.out.length)
611 != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
614 duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
615 chip->duration[TPM_SHORT] =
616 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
617 chip->duration[TPM_MEDIUM] =
618 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
619 chip->duration[TPM_LONG] =
620 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
622 /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
623 * value wrong and apparently reports msecs rather than usecs. So we
624 * fix up the resulting too-small TPM_SHORT value to make things work.
625 * We also scale the TPM_MEDIUM and -_LONG values by 1000.
627 if (chip->duration[TPM_SHORT] < (HZ / 100)) {
628 chip->duration[TPM_SHORT] = HZ;
629 chip->duration[TPM_MEDIUM] *= 1000;
630 chip->duration[TPM_LONG] *= 1000;
631 chip->duration_adjusted = true;
632 dev_info(&chip->dev, "Adjusting TPM timeout parameters.");
636 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
638 #define TPM_ORD_CONTINUE_SELFTEST 83
639 #define CONTINUE_SELFTEST_RESULT_SIZE 10
641 static const struct tpm_input_header continue_selftest_header = {
642 .tag = TPM_TAG_RQU_COMMAND,
643 .length = cpu_to_be32(10),
644 .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
648 * tpm_continue_selftest -- run TPM's selftest
649 * @chip: TPM chip to use
651 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
654 static int tpm_continue_selftest(struct tpm_chip *chip)
657 struct tpm_cmd_t cmd;
659 cmd.header.in = continue_selftest_header;
660 rc = tpm_transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE, 0,
661 "continue selftest");
665 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
666 #define READ_PCR_RESULT_SIZE 30
667 static const struct tpm_input_header pcrread_header = {
668 .tag = TPM_TAG_RQU_COMMAND,
669 .length = cpu_to_be32(14),
670 .ordinal = TPM_ORDINAL_PCRREAD
673 int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
676 struct tpm_cmd_t cmd;
678 cmd.header.in = pcrread_header;
679 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
680 rc = tpm_transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE, 0,
681 "attempting to read a pcr value");
684 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
690 * tpm_is_tpm2 - is the chip a TPM2 chip?
691 * @chip_num: tpm idx # or ANY
693 * Returns < 0 on error, and 1 or 0 on success depending whether the chip
696 int tpm_is_tpm2(u32 chip_num)
698 struct tpm_chip *chip;
701 chip = tpm_chip_find_get(chip_num);
705 rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0;
711 EXPORT_SYMBOL_GPL(tpm_is_tpm2);
714 * tpm_pcr_read - read a pcr value
715 * @chip_num: tpm idx # or ANY
716 * @pcr_idx: pcr idx to retrieve
717 * @res_buf: TPM_PCR value
718 * size of res_buf is 20 bytes (or NULL if you don't care)
720 * The TPM driver should be built-in, but for whatever reason it
721 * isn't, protect against the chip disappearing, by incrementing
722 * the module usage count.
724 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
726 struct tpm_chip *chip;
729 chip = tpm_chip_find_get(chip_num);
732 if (chip->flags & TPM_CHIP_FLAG_TPM2)
733 rc = tpm2_pcr_read(chip, pcr_idx, res_buf);
735 rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf);
739 EXPORT_SYMBOL_GPL(tpm_pcr_read);
742 * tpm_pcr_extend - extend pcr value with hash
743 * @chip_num: tpm idx # or AN&
744 * @pcr_idx: pcr idx to extend
745 * @hash: hash value used to extend pcr value
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.
751 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
752 #define EXTEND_PCR_RESULT_SIZE 34
753 static const struct tpm_input_header pcrextend_header = {
754 .tag = TPM_TAG_RQU_COMMAND,
755 .length = cpu_to_be32(34),
756 .ordinal = TPM_ORD_PCR_EXTEND
759 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
761 struct tpm_cmd_t cmd;
763 struct tpm_chip *chip;
765 chip = tpm_chip_find_get(chip_num);
769 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
770 rc = tpm2_pcr_extend(chip, pcr_idx, hash);
775 cmd.header.in = pcrextend_header;
776 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
777 memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
778 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE, 0,
779 "attempting extend a PCR value");
784 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
787 * tpm_do_selftest - have the TPM continue its selftest and wait until it
788 * can receive further commands
789 * @chip: TPM chip to use
791 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
794 int tpm_do_selftest(struct tpm_chip *chip)
798 unsigned int delay_msec = 100;
799 unsigned long duration;
800 u8 dummy[TPM_DIGEST_SIZE];
802 duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST);
804 loops = jiffies_to_msecs(duration) / delay_msec;
806 rc = tpm_continue_selftest(chip);
807 if (rc == TPM_ERR_INVALID_POSTINIT) {
808 chip->flags |= TPM_CHIP_FLAG_ALWAYS_POWERED;
809 dev_info(&chip->dev, "TPM not ready (%d)\n", rc);
811 /* This may fail if there was no TPM driver during a suspend/resume
812 * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
818 /* Attempt to read a PCR value */
819 rc = tpm_pcr_read_dev(chip, 0, dummy);
821 /* Some buggy TPMs will not respond to tpm_tis_ready() for
822 * around 300ms while the self test is ongoing, keep trying
823 * until the self test duration expires. */
827 "TPM command timed out during continue self test");
832 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
834 "TPM is disabled/deactivated (0x%X)\n", rc);
835 /* TPM is disabled and/or deactivated; driver can
836 * proceed and TPM does handle commands for
837 * suspend/resume correctly
841 if (rc != TPM_WARN_DOING_SELFTEST)
844 } while (--loops > 0);
848 EXPORT_SYMBOL_GPL(tpm_do_selftest);
851 * tpm1_auto_startup - Perform the standard automatic TPM initialization
853 * @chip: TPM chip to use
855 * Returns 0 on success, < 0 in case of fatal error.
857 int tpm1_auto_startup(struct tpm_chip *chip)
861 rc = tpm_get_timeouts(chip);
864 rc = tpm_do_selftest(chip);
866 dev_err(&chip->dev, "TPM self test failed\n");
877 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
879 struct tpm_chip *chip;
882 chip = tpm_chip_find_get(chip_num);
886 rc = tpm_transmit_cmd(chip, cmd, buflen, 0, "attempting tpm_cmd");
891 EXPORT_SYMBOL_GPL(tpm_send);
893 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
894 bool check_cancel, bool *canceled)
896 u8 status = chip->ops->status(chip);
899 if ((status & mask) == mask)
901 if (check_cancel && chip->ops->req_canceled(chip, status)) {
908 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
909 wait_queue_head_t *queue, bool check_cancel)
914 bool canceled = false;
916 /* check current status */
917 status = chip->ops->status(chip);
918 if ((status & mask) == mask)
921 stop = jiffies + timeout;
923 if (chip->flags & TPM_CHIP_FLAG_IRQ) {
925 timeout = stop - jiffies;
926 if ((long)timeout <= 0)
928 rc = wait_event_interruptible_timeout(*queue,
929 wait_for_tpm_stat_cond(chip, mask, check_cancel,
937 if (rc == -ERESTARTSYS && freezing(current)) {
938 clear_thread_flag(TIF_SIGPENDING);
944 status = chip->ops->status(chip);
945 if ((status & mask) == mask)
947 } while (time_before(jiffies, stop));
951 EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
953 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
954 #define SAVESTATE_RESULT_SIZE 10
956 static const struct tpm_input_header savestate_header = {
957 .tag = TPM_TAG_RQU_COMMAND,
958 .length = cpu_to_be32(10),
959 .ordinal = TPM_ORD_SAVESTATE
963 * We are about to suspend. Save the TPM state
964 * so that it can be restored.
966 int tpm_pm_suspend(struct device *dev)
968 struct tpm_chip *chip = dev_get_drvdata(dev);
969 struct tpm_cmd_t cmd;
972 u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
977 if (chip->flags & TPM_CHIP_FLAG_ALWAYS_POWERED)
980 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
981 tpm2_shutdown(chip, TPM2_SU_STATE);
985 /* for buggy tpm, flush pcrs with extend to selected dummy */
986 if (tpm_suspend_pcr) {
987 cmd.header.in = pcrextend_header;
988 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
989 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
991 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE, 0,
992 "extending dummy pcr before suspend");
995 /* now do the actual savestate */
996 for (try = 0; try < TPM_RETRY; try++) {
997 cmd.header.in = savestate_header;
998 rc = tpm_transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, 0,
1002 * If the TPM indicates that it is too busy to respond to
1003 * this command then retry before giving up. It can take
1004 * several seconds for this TPM to be ready.
1006 * This can happen if the TPM has already been sent the
1007 * SaveState command before the driver has loaded. TCG 1.2
1008 * specification states that any communication after SaveState
1009 * may cause the TPM to invalidate previously saved state.
1011 if (rc != TPM_WARN_RETRY)
1013 msleep(TPM_TIMEOUT_RETRY);
1018 "Error (%d) sending savestate before suspend\n", rc);
1020 dev_warn(&chip->dev, "TPM savestate took %dms\n",
1021 try * TPM_TIMEOUT_RETRY);
1025 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1028 * Resume from a power safe. The BIOS already restored
1031 int tpm_pm_resume(struct device *dev)
1033 struct tpm_chip *chip = dev_get_drvdata(dev);
1040 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1042 #define TPM_GETRANDOM_RESULT_SIZE 18
1043 static const struct tpm_input_header tpm_getrandom_header = {
1044 .tag = TPM_TAG_RQU_COMMAND,
1045 .length = cpu_to_be32(14),
1046 .ordinal = TPM_ORD_GET_RANDOM
1050 * tpm_get_random() - Get random bytes from the tpm's RNG
1051 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1052 * @out: destination buffer for the random bytes
1053 * @max: the max number of bytes to write to @out
1055 * Returns < 0 on error and the number of bytes read on success
1057 int tpm_get_random(u32 chip_num, u8 *out, size_t max)
1059 struct tpm_chip *chip;
1060 struct tpm_cmd_t tpm_cmd;
1061 u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA);
1062 int err, total = 0, retries = 5;
1065 if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
1068 chip = tpm_chip_find_get(chip_num);
1072 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
1073 err = tpm2_get_random(chip, out, max);
1079 tpm_cmd.header.in = tpm_getrandom_header;
1080 tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
1082 err = tpm_transmit_cmd(chip, &tpm_cmd,
1083 TPM_GETRANDOM_RESULT_SIZE + num_bytes,
1084 0, "attempting get random");
1088 recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
1089 if (recd > num_bytes) {
1094 memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
1099 } while (retries-- && total < max);
1102 return total ? total : -EIO;
1104 EXPORT_SYMBOL_GPL(tpm_get_random);
1107 * tpm_seal_trusted() - seal a trusted key
1108 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1109 * @options: authentication values and other options
1110 * @payload: the key data in clear and encrypted form
1112 * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips
1115 int tpm_seal_trusted(u32 chip_num, struct trusted_key_payload *payload,
1116 struct trusted_key_options *options)
1118 struct tpm_chip *chip;
1121 chip = tpm_chip_find_get(chip_num);
1122 if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1125 rc = tpm2_seal_trusted(chip, payload, options);
1130 EXPORT_SYMBOL_GPL(tpm_seal_trusted);
1133 * tpm_unseal_trusted() - unseal a trusted key
1134 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1135 * @options: authentication values and other options
1136 * @payload: the key data in clear and encrypted form
1138 * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips
1141 int tpm_unseal_trusted(u32 chip_num, struct trusted_key_payload *payload,
1142 struct trusted_key_options *options)
1144 struct tpm_chip *chip;
1147 chip = tpm_chip_find_get(chip_num);
1148 if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1151 rc = tpm2_unseal_trusted(chip, payload, options);
1157 EXPORT_SYMBOL_GPL(tpm_unseal_trusted);
1159 static int __init tpm_init(void)
1163 tpm_class = class_create(THIS_MODULE, "tpm");
1164 if (IS_ERR(tpm_class)) {
1165 pr_err("couldn't create tpm class\n");
1166 return PTR_ERR(tpm_class);
1169 rc = alloc_chrdev_region(&tpm_devt, 0, TPM_NUM_DEVICES, "tpm");
1171 pr_err("tpm: failed to allocate char dev region\n");
1172 class_destroy(tpm_class);
1179 static void __exit tpm_exit(void)
1181 idr_destroy(&dev_nums_idr);
1182 class_destroy(tpm_class);
1183 unregister_chrdev_region(tpm_devt, TPM_NUM_DEVICES);
1186 subsys_initcall(tpm_init);
1187 module_exit(tpm_exit);
1189 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1190 MODULE_DESCRIPTION("TPM Driver");
1191 MODULE_VERSION("2.0");
1192 MODULE_LICENSE("GPL");