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->vendor.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 char *buf,
340 if (bufsiz > TPM_BUFSIZE)
341 bufsiz = TPM_BUFSIZE;
343 count = be32_to_cpu(*((__be32 *) (buf + 2)));
344 ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
347 if (count > bufsiz) {
349 "invalid count value %x %zx\n", count, bufsiz);
353 mutex_lock(&chip->tpm_mutex);
355 rc = chip->ops->send(chip, (u8 *) buf, count);
358 "tpm_transmit: tpm_send: error %zd\n", rc);
362 if (chip->flags & TPM_CHIP_FLAG_IRQ)
365 if (chip->flags & TPM_CHIP_FLAG_TPM2)
366 stop = jiffies + tpm2_calc_ordinal_duration(chip, ordinal);
368 stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
370 u8 status = chip->ops->status(chip);
371 if ((status & chip->ops->req_complete_mask) ==
372 chip->ops->req_complete_val)
375 if (chip->ops->req_canceled(chip, status)) {
376 dev_err(&chip->dev, "Operation Canceled\n");
381 msleep(TPM_TIMEOUT); /* CHECK */
383 } while (time_before(jiffies, stop));
385 chip->ops->cancel(chip);
386 dev_err(&chip->dev, "Operation Timed out\n");
391 rc = chip->ops->recv(chip, (u8 *) buf, bufsiz);
394 "tpm_transmit: tpm_recv: error %zd\n", rc);
396 mutex_unlock(&chip->tpm_mutex);
400 #define TPM_DIGEST_SIZE 20
401 #define TPM_RET_CODE_IDX 6
403 ssize_t tpm_transmit_cmd(struct tpm_chip *chip, void *cmd,
404 int len, const char *desc)
406 struct tpm_output_header *header;
409 len = tpm_transmit(chip, (u8 *) cmd, len);
412 else if (len < TPM_HEADER_SIZE)
417 err = be32_to_cpu(header->return_code);
418 if (err != 0 && desc)
419 dev_err(&chip->dev, "A TPM error (%d) occurred %s\n", err,
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)
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
435 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
438 struct tpm_cmd_t tpm_cmd;
440 struct tpm_chip *chip = dev_get_drvdata(dev);
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));
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;
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;
457 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
459 *cap = tpm_cmd.params.getcap_out.cap;
463 void tpm_gen_interrupt(struct tpm_chip *chip)
465 struct tpm_cmd_t tpm_cmd;
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;
473 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
474 "attempting to determine the timeouts");
476 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
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
488 static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
490 struct tpm_cmd_t start_cmd;
491 start_cmd.header.in = tpm_startup_header;
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");
498 int tpm_get_timeouts(struct tpm_chip *chip)
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;
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);
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);
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->dev, "Issuing TPM_STARTUP");
531 if (tpm_startup(chip, TPM_ST_CLEAR))
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,
543 "A TPM error (%zd) occurred attempting to determine the timeouts\n",
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))
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));
560 * Provide ability for vendor overrides of timeout values in case
563 if (chip->ops->update_timeouts != NULL)
564 chip->vendor.timeout_adjusted =
565 chip->ops->update_timeouts(chip, new_timeout);
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) {
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;
579 /* Report adjusted timeouts */
580 if (chip->vendor.timeout_adjusted) {
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]);
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]);
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;
600 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
601 "attempting to determine the durations");
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))
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));
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.
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->dev, "Adjusting TPM timeout parameters.");
632 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
634 #define TPM_ORD_CONTINUE_SELFTEST 83
635 #define CONTINUE_SELFTEST_RESULT_SIZE 10
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),
644 * tpm_continue_selftest -- run TPM's selftest
645 * @chip: TPM chip to use
647 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
650 static int tpm_continue_selftest(struct tpm_chip *chip)
653 struct tpm_cmd_t cmd;
655 cmd.header.in = continue_selftest_header;
656 rc = tpm_transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
657 "continue selftest");
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
669 int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
672 struct tpm_cmd_t cmd;
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");
680 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
686 * tpm_is_tpm2 - is the chip a TPM2 chip?
687 * @chip_num: tpm idx # or ANY
689 * Returns < 0 on error, and 1 or 0 on success depending whether the chip
692 int tpm_is_tpm2(u32 chip_num)
694 struct tpm_chip *chip;
697 chip = tpm_chip_find_get(chip_num);
701 rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0;
707 EXPORT_SYMBOL_GPL(tpm_is_tpm2);
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)
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.
720 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
722 struct tpm_chip *chip;
725 chip = tpm_chip_find_get(chip_num);
728 if (chip->flags & TPM_CHIP_FLAG_TPM2)
729 rc = tpm2_pcr_read(chip, pcr_idx, res_buf);
731 rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf);
735 EXPORT_SYMBOL_GPL(tpm_pcr_read);
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
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.
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
755 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
757 struct tpm_cmd_t cmd;
759 struct tpm_chip *chip;
761 chip = tpm_chip_find_get(chip_num);
765 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
766 rc = tpm2_pcr_extend(chip, pcr_idx, hash);
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");
780 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
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
787 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
790 int tpm_do_selftest(struct tpm_chip *chip)
794 unsigned int delay_msec = 100;
795 unsigned long duration;
796 struct tpm_cmd_t cmd;
798 duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST);
800 loops = jiffies_to_msecs(duration) / delay_msec;
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)
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. */
820 "TPM command timed out during continue self test");
825 if (rc < TPM_HEADER_SIZE)
828 rc = be32_to_cpu(cmd.header.out.return_code);
829 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
831 "TPM is disabled/deactivated (0x%X)\n", rc);
832 /* TPM is disabled and/or deactivated; driver can
833 * proceed and TPM does handle commands for
834 * suspend/resume correctly
838 if (rc != TPM_WARN_DOING_SELFTEST)
841 } while (--loops > 0);
845 EXPORT_SYMBOL_GPL(tpm_do_selftest);
847 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
849 struct tpm_chip *chip;
852 chip = tpm_chip_find_get(chip_num);
856 rc = tpm_transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
861 EXPORT_SYMBOL_GPL(tpm_send);
863 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
864 bool check_cancel, bool *canceled)
866 u8 status = chip->ops->status(chip);
869 if ((status & mask) == mask)
871 if (check_cancel && chip->ops->req_canceled(chip, status)) {
878 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
879 wait_queue_head_t *queue, bool check_cancel)
884 bool canceled = false;
886 /* check current status */
887 status = chip->ops->status(chip);
888 if ((status & mask) == mask)
891 stop = jiffies + timeout;
893 if (chip->flags & TPM_CHIP_FLAG_IRQ) {
895 timeout = stop - jiffies;
896 if ((long)timeout <= 0)
898 rc = wait_event_interruptible_timeout(*queue,
899 wait_for_tpm_stat_cond(chip, mask, check_cancel,
907 if (rc == -ERESTARTSYS && freezing(current)) {
908 clear_thread_flag(TIF_SIGPENDING);
914 status = chip->ops->status(chip);
915 if ((status & mask) == mask)
917 } while (time_before(jiffies, stop));
921 EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
923 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
924 #define SAVESTATE_RESULT_SIZE 10
926 static struct tpm_input_header savestate_header = {
927 .tag = TPM_TAG_RQU_COMMAND,
928 .length = cpu_to_be32(10),
929 .ordinal = TPM_ORD_SAVESTATE
933 * We are about to suspend. Save the TPM state
934 * so that it can be restored.
936 int tpm_pm_suspend(struct device *dev)
938 struct tpm_chip *chip = dev_get_drvdata(dev);
939 struct tpm_cmd_t cmd;
942 u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
947 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
948 tpm2_shutdown(chip, TPM2_SU_STATE);
952 /* for buggy tpm, flush pcrs with extend to selected dummy */
953 if (tpm_suspend_pcr) {
954 cmd.header.in = pcrextend_header;
955 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
956 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
958 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
959 "extending dummy pcr before suspend");
962 /* now do the actual savestate */
963 for (try = 0; try < TPM_RETRY; try++) {
964 cmd.header.in = savestate_header;
965 rc = tpm_transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, NULL);
968 * If the TPM indicates that it is too busy to respond to
969 * this command then retry before giving up. It can take
970 * several seconds for this TPM to be ready.
972 * This can happen if the TPM has already been sent the
973 * SaveState command before the driver has loaded. TCG 1.2
974 * specification states that any communication after SaveState
975 * may cause the TPM to invalidate previously saved state.
977 if (rc != TPM_WARN_RETRY)
979 msleep(TPM_TIMEOUT_RETRY);
984 "Error (%d) sending savestate before suspend\n", rc);
986 dev_warn(&chip->dev, "TPM savestate took %dms\n",
987 try * TPM_TIMEOUT_RETRY);
991 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
994 * Resume from a power safe. The BIOS already restored
997 int tpm_pm_resume(struct device *dev)
999 struct tpm_chip *chip = dev_get_drvdata(dev);
1006 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1008 #define TPM_GETRANDOM_RESULT_SIZE 18
1009 static struct tpm_input_header tpm_getrandom_header = {
1010 .tag = TPM_TAG_RQU_COMMAND,
1011 .length = cpu_to_be32(14),
1012 .ordinal = TPM_ORD_GET_RANDOM
1016 * tpm_get_random() - Get random bytes from the tpm's RNG
1017 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1018 * @out: destination buffer for the random bytes
1019 * @max: the max number of bytes to write to @out
1021 * Returns < 0 on error and the number of bytes read on success
1023 int tpm_get_random(u32 chip_num, u8 *out, size_t max)
1025 struct tpm_chip *chip;
1026 struct tpm_cmd_t tpm_cmd;
1027 u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA);
1028 int err, total = 0, retries = 5;
1031 if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
1034 chip = tpm_chip_find_get(chip_num);
1038 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
1039 err = tpm2_get_random(chip, out, max);
1045 tpm_cmd.header.in = tpm_getrandom_header;
1046 tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
1048 err = tpm_transmit_cmd(chip, &tpm_cmd,
1049 TPM_GETRANDOM_RESULT_SIZE + num_bytes,
1050 "attempting get random");
1054 recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
1055 memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
1060 } while (retries-- && total < max);
1063 return total ? total : -EIO;
1065 EXPORT_SYMBOL_GPL(tpm_get_random);
1068 * tpm_seal_trusted() - seal a trusted key
1069 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1070 * @options: authentication values and other options
1071 * @payload: the key data in clear and encrypted form
1073 * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips
1076 int tpm_seal_trusted(u32 chip_num, struct trusted_key_payload *payload,
1077 struct trusted_key_options *options)
1079 struct tpm_chip *chip;
1082 chip = tpm_chip_find_get(chip_num);
1083 if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1086 rc = tpm2_seal_trusted(chip, payload, options);
1091 EXPORT_SYMBOL_GPL(tpm_seal_trusted);
1094 * tpm_unseal_trusted() - unseal a trusted key
1095 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1096 * @options: authentication values and other options
1097 * @payload: the key data in clear and encrypted form
1099 * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips
1102 int tpm_unseal_trusted(u32 chip_num, struct trusted_key_payload *payload,
1103 struct trusted_key_options *options)
1105 struct tpm_chip *chip;
1108 chip = tpm_chip_find_get(chip_num);
1109 if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1112 rc = tpm2_unseal_trusted(chip, payload, options);
1118 EXPORT_SYMBOL_GPL(tpm_unseal_trusted);
1120 static int __init tpm_init(void)
1124 tpm_class = class_create(THIS_MODULE, "tpm");
1125 if (IS_ERR(tpm_class)) {
1126 pr_err("couldn't create tpm class\n");
1127 return PTR_ERR(tpm_class);
1130 rc = alloc_chrdev_region(&tpm_devt, 0, TPM_NUM_DEVICES, "tpm");
1132 pr_err("tpm: failed to allocate char dev region\n");
1133 class_destroy(tpm_class);
1140 static void __exit tpm_exit(void)
1142 idr_destroy(&dev_nums_idr);
1143 class_destroy(tpm_class);
1144 unregister_chrdev_region(tpm_devt, TPM_NUM_DEVICES);
1147 subsys_initcall(tpm_init);
1148 module_exit(tpm_exit);
1150 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1151 MODULE_DESCRIPTION("TPM Driver");
1152 MODULE_VERSION("2.0");
1153 MODULE_LICENSE("GPL");