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;
313 u8 category = (ordinal >> 24) & 0xFF;
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];
319 if (duration_idx != TPM_UNDEFINED)
320 duration = chip->vendor.duration[duration_idx];
326 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
329 * Internal kernel interface to transmit TPM commands
331 ssize_t tpm_transmit(struct tpm_chip *chip, const u8 *buf, size_t bufsiz,
338 if (bufsiz > TPM_BUFSIZE)
339 bufsiz = TPM_BUFSIZE;
341 count = be32_to_cpu(*((__be32 *) (buf + 2)));
342 ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
345 if (count > bufsiz) {
347 "invalid count value %x %zx\n", count, bufsiz);
351 if (!(flags & TPM_TRANSMIT_UNLOCKED))
352 mutex_lock(&chip->tpm_mutex);
354 rc = chip->ops->send(chip, (u8 *) buf, count);
357 "tpm_transmit: tpm_send: error %zd\n", rc);
361 if (chip->vendor.irq)
364 if (chip->flags & TPM_CHIP_FLAG_TPM2)
365 stop = jiffies + tpm2_calc_ordinal_duration(chip, ordinal);
367 stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
369 u8 status = chip->ops->status(chip);
370 if ((status & chip->ops->req_complete_mask) ==
371 chip->ops->req_complete_val)
374 if (chip->ops->req_canceled(chip, status)) {
375 dev_err(chip->pdev, "Operation Canceled\n");
380 msleep(TPM_TIMEOUT); /* CHECK */
382 } while (time_before(jiffies, stop));
384 chip->ops->cancel(chip);
385 dev_err(chip->pdev, "Operation Timed out\n");
390 rc = chip->ops->recv(chip, (u8 *) buf, bufsiz);
393 "tpm_transmit: tpm_recv: error %zd\n", rc);
395 if (!(flags & TPM_TRANSMIT_UNLOCKED))
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, const void *cmd,
404 int len, unsigned int flags, const char *desc)
406 const struct tpm_output_header *header;
409 len = tpm_transmit(chip, (const u8 *)cmd, len, flags);
412 else if (len < TPM_HEADER_SIZE)
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,
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, 0,
460 *cap = tpm_cmd.params.getcap_out.cap;
464 void tpm_gen_interrupt(struct tpm_chip *chip)
466 struct tpm_cmd_t tpm_cmd;
469 tpm_cmd.header.in = tpm_getcap_header;
470 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
471 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
472 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
474 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 0,
475 "attempting to determine the timeouts");
477 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
479 #define TPM_ORD_STARTUP cpu_to_be32(153)
480 #define TPM_ST_CLEAR cpu_to_be16(1)
481 #define TPM_ST_STATE cpu_to_be16(2)
482 #define TPM_ST_DEACTIVATED cpu_to_be16(3)
483 static const struct tpm_input_header tpm_startup_header = {
484 .tag = TPM_TAG_RQU_COMMAND,
485 .length = cpu_to_be32(12),
486 .ordinal = TPM_ORD_STARTUP
489 static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
491 struct tpm_cmd_t start_cmd;
492 start_cmd.header.in = tpm_startup_header;
494 start_cmd.params.startup_in.startup_type = startup_type;
495 return tpm_transmit_cmd(chip, &start_cmd, TPM_INTERNAL_RESULT_SIZE, 0,
496 "attempting to start the TPM");
499 int tpm_get_timeouts(struct tpm_chip *chip)
501 struct tpm_cmd_t tpm_cmd;
502 unsigned long new_timeout[4];
503 unsigned long old_timeout[4];
504 struct duration_t *duration_cap;
507 tpm_cmd.header.in = tpm_getcap_header;
508 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
509 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
510 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
511 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 0,
514 if (rc == TPM_ERR_INVALID_POSTINIT) {
515 /* The TPM is not started, we are the first to talk to it.
516 Execute a startup command. */
517 dev_info(chip->pdev, "Issuing TPM_STARTUP");
518 if (tpm_startup(chip, TPM_ST_CLEAR))
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,
530 "A TPM error (%zd) occurred attempting to determine the timeouts\n",
535 if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
536 be32_to_cpu(tpm_cmd.header.out.length)
537 != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
540 old_timeout[0] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.a);
541 old_timeout[1] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.b);
542 old_timeout[2] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.c);
543 old_timeout[3] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.d);
544 memcpy(new_timeout, old_timeout, sizeof(new_timeout));
547 * Provide ability for vendor overrides of timeout values in case
550 if (chip->ops->update_timeouts != NULL)
551 chip->vendor.timeout_adjusted =
552 chip->ops->update_timeouts(chip, new_timeout);
554 if (!chip->vendor.timeout_adjusted) {
555 /* Don't overwrite default if value is 0 */
556 if (new_timeout[0] != 0 && new_timeout[0] < 1000) {
559 /* timeouts in msec rather usec */
560 for (i = 0; i != ARRAY_SIZE(new_timeout); i++)
561 new_timeout[i] *= 1000;
562 chip->vendor.timeout_adjusted = true;
566 /* Report adjusted timeouts */
567 if (chip->vendor.timeout_adjusted) {
569 HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n",
570 old_timeout[0], new_timeout[0],
571 old_timeout[1], new_timeout[1],
572 old_timeout[2], new_timeout[2],
573 old_timeout[3], new_timeout[3]);
576 chip->vendor.timeout_a = usecs_to_jiffies(new_timeout[0]);
577 chip->vendor.timeout_b = usecs_to_jiffies(new_timeout[1]);
578 chip->vendor.timeout_c = usecs_to_jiffies(new_timeout[2]);
579 chip->vendor.timeout_d = usecs_to_jiffies(new_timeout[3]);
582 tpm_cmd.header.in = tpm_getcap_header;
583 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
584 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
585 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
587 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 0,
588 "attempting to determine the durations");
592 if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
593 be32_to_cpu(tpm_cmd.header.out.length)
594 != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
597 duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
598 chip->vendor.duration[TPM_SHORT] =
599 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
600 chip->vendor.duration[TPM_MEDIUM] =
601 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
602 chip->vendor.duration[TPM_LONG] =
603 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
605 /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
606 * value wrong and apparently reports msecs rather than usecs. So we
607 * fix up the resulting too-small TPM_SHORT value to make things work.
608 * We also scale the TPM_MEDIUM and -_LONG values by 1000.
610 if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
611 chip->vendor.duration[TPM_SHORT] = HZ;
612 chip->vendor.duration[TPM_MEDIUM] *= 1000;
613 chip->vendor.duration[TPM_LONG] *= 1000;
614 chip->vendor.duration_adjusted = true;
615 dev_info(chip->pdev, "Adjusting TPM timeout parameters.");
619 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
621 #define TPM_ORD_CONTINUE_SELFTEST 83
622 #define CONTINUE_SELFTEST_RESULT_SIZE 10
624 static struct tpm_input_header continue_selftest_header = {
625 .tag = TPM_TAG_RQU_COMMAND,
626 .length = cpu_to_be32(10),
627 .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
631 * tpm_continue_selftest -- run TPM's selftest
632 * @chip: TPM chip to use
634 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
637 static int tpm_continue_selftest(struct tpm_chip *chip)
640 struct tpm_cmd_t cmd;
642 cmd.header.in = continue_selftest_header;
643 rc = tpm_transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE, 0,
644 "continue selftest");
648 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
649 #define READ_PCR_RESULT_SIZE 30
650 static struct tpm_input_header pcrread_header = {
651 .tag = TPM_TAG_RQU_COMMAND,
652 .length = cpu_to_be32(14),
653 .ordinal = TPM_ORDINAL_PCRREAD
656 int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
659 struct tpm_cmd_t cmd;
661 cmd.header.in = pcrread_header;
662 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
663 rc = tpm_transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE, 0,
664 "attempting to read a pcr value");
667 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
673 * tpm_is_tpm2 - is the chip a TPM2 chip?
674 * @chip_num: tpm idx # or ANY
676 * Returns < 0 on error, and 1 or 0 on success depending whether the chip
679 int tpm_is_tpm2(u32 chip_num)
681 struct tpm_chip *chip;
684 chip = tpm_chip_find_get(chip_num);
688 rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0;
694 EXPORT_SYMBOL_GPL(tpm_is_tpm2);
697 * tpm_pcr_read - read a pcr value
698 * @chip_num: tpm idx # or ANY
699 * @pcr_idx: pcr idx to retrieve
700 * @res_buf: TPM_PCR value
701 * size of res_buf is 20 bytes (or NULL if you don't care)
703 * The TPM driver should be built-in, but for whatever reason it
704 * isn't, protect against the chip disappearing, by incrementing
705 * the module usage count.
707 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
709 struct tpm_chip *chip;
712 chip = tpm_chip_find_get(chip_num);
715 if (chip->flags & TPM_CHIP_FLAG_TPM2)
716 rc = tpm2_pcr_read(chip, pcr_idx, res_buf);
718 rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf);
722 EXPORT_SYMBOL_GPL(tpm_pcr_read);
725 * tpm_pcr_extend - extend pcr value with hash
726 * @chip_num: tpm idx # or AN&
727 * @pcr_idx: pcr idx to extend
728 * @hash: hash value used to extend pcr value
730 * The TPM driver should be built-in, but for whatever reason it
731 * isn't, protect against the chip disappearing, by incrementing
732 * the module usage count.
734 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
735 #define EXTEND_PCR_RESULT_SIZE 34
736 static struct tpm_input_header pcrextend_header = {
737 .tag = TPM_TAG_RQU_COMMAND,
738 .length = cpu_to_be32(34),
739 .ordinal = TPM_ORD_PCR_EXTEND
742 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
744 struct tpm_cmd_t cmd;
746 struct tpm_chip *chip;
748 chip = tpm_chip_find_get(chip_num);
752 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
753 rc = tpm2_pcr_extend(chip, pcr_idx, hash);
758 cmd.header.in = pcrextend_header;
759 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
760 memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
761 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE, 0,
762 "attempting extend a PCR value");
767 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
770 * tpm_do_selftest - have the TPM continue its selftest and wait until it
771 * can receive further commands
772 * @chip: TPM chip to use
774 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
777 int tpm_do_selftest(struct tpm_chip *chip)
781 unsigned int delay_msec = 100;
782 unsigned long duration;
783 struct tpm_cmd_t cmd;
785 duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST);
787 loops = jiffies_to_msecs(duration) / delay_msec;
789 rc = tpm_continue_selftest(chip);
790 /* This may fail if there was no TPM driver during a suspend/resume
791 * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
797 /* Attempt to read a PCR value */
798 cmd.header.in = pcrread_header;
799 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(0);
800 rc = tpm_transmit(chip, (u8 *) &cmd, READ_PCR_RESULT_SIZE, 0);
801 /* Some buggy TPMs will not respond to tpm_tis_ready() for
802 * around 300ms while the self test is ongoing, keep trying
803 * until the self test duration expires. */
805 dev_info(chip->pdev, HW_ERR "TPM command timed out during continue self test");
810 if (rc < TPM_HEADER_SIZE)
813 rc = be32_to_cpu(cmd.header.out.return_code);
814 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
816 "TPM is disabled/deactivated (0x%X)\n", rc);
817 /* TPM is disabled and/or deactivated; driver can
818 * proceed and TPM does handle commands for
819 * suspend/resume correctly
823 if (rc != TPM_WARN_DOING_SELFTEST)
826 } while (--loops > 0);
830 EXPORT_SYMBOL_GPL(tpm_do_selftest);
832 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
834 struct tpm_chip *chip;
837 chip = tpm_chip_find_get(chip_num);
841 rc = tpm_transmit_cmd(chip, cmd, buflen, 0, "attempting tpm_cmd");
846 EXPORT_SYMBOL_GPL(tpm_send);
848 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
849 bool check_cancel, bool *canceled)
851 u8 status = chip->ops->status(chip);
854 if ((status & mask) == mask)
856 if (check_cancel && chip->ops->req_canceled(chip, status)) {
863 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
864 wait_queue_head_t *queue, bool check_cancel)
869 bool canceled = false;
871 /* check current status */
872 status = chip->ops->status(chip);
873 if ((status & mask) == mask)
876 stop = jiffies + timeout;
878 if (chip->vendor.irq) {
880 timeout = stop - jiffies;
881 if ((long)timeout <= 0)
883 rc = wait_event_interruptible_timeout(*queue,
884 wait_for_tpm_stat_cond(chip, mask, check_cancel,
892 if (rc == -ERESTARTSYS && freezing(current)) {
893 clear_thread_flag(TIF_SIGPENDING);
899 status = chip->ops->status(chip);
900 if ((status & mask) == mask)
902 } while (time_before(jiffies, stop));
906 EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
908 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
909 #define SAVESTATE_RESULT_SIZE 10
911 static struct tpm_input_header savestate_header = {
912 .tag = TPM_TAG_RQU_COMMAND,
913 .length = cpu_to_be32(10),
914 .ordinal = TPM_ORD_SAVESTATE
918 * We are about to suspend. Save the TPM state
919 * so that it can be restored.
921 int tpm_pm_suspend(struct device *dev)
923 struct tpm_chip *chip = dev_get_drvdata(dev);
924 struct tpm_cmd_t cmd;
927 u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
932 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
933 tpm2_shutdown(chip, TPM2_SU_STATE);
937 /* for buggy tpm, flush pcrs with extend to selected dummy */
938 if (tpm_suspend_pcr) {
939 cmd.header.in = pcrextend_header;
940 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
941 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
943 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE, 0,
944 "extending dummy pcr before suspend");
947 /* now do the actual savestate */
948 for (try = 0; try < TPM_RETRY; try++) {
949 cmd.header.in = savestate_header;
950 rc = tpm_transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, 0,
954 * If the TPM indicates that it is too busy to respond to
955 * this command then retry before giving up. It can take
956 * several seconds for this TPM to be ready.
958 * This can happen if the TPM has already been sent the
959 * SaveState command before the driver has loaded. TCG 1.2
960 * specification states that any communication after SaveState
961 * may cause the TPM to invalidate previously saved state.
963 if (rc != TPM_WARN_RETRY)
965 msleep(TPM_TIMEOUT_RETRY);
970 "Error (%d) sending savestate before suspend\n", rc);
972 dev_warn(chip->pdev, "TPM savestate took %dms\n",
973 try * TPM_TIMEOUT_RETRY);
977 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
980 * Resume from a power safe. The BIOS already restored
983 int tpm_pm_resume(struct device *dev)
985 struct tpm_chip *chip = dev_get_drvdata(dev);
992 EXPORT_SYMBOL_GPL(tpm_pm_resume);
994 #define TPM_GETRANDOM_RESULT_SIZE 18
995 static struct tpm_input_header tpm_getrandom_header = {
996 .tag = TPM_TAG_RQU_COMMAND,
997 .length = cpu_to_be32(14),
998 .ordinal = TPM_ORD_GET_RANDOM
1002 * tpm_get_random() - Get random bytes from the tpm's RNG
1003 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1004 * @out: destination buffer for the random bytes
1005 * @max: the max number of bytes to write to @out
1007 * Returns < 0 on error and the number of bytes read on success
1009 int tpm_get_random(u32 chip_num, u8 *out, size_t max)
1011 struct tpm_chip *chip;
1012 struct tpm_cmd_t tpm_cmd;
1013 u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA);
1014 int err, total = 0, retries = 5;
1017 if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
1020 chip = tpm_chip_find_get(chip_num);
1024 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
1025 err = tpm2_get_random(chip, out, max);
1031 tpm_cmd.header.in = tpm_getrandom_header;
1032 tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
1034 err = tpm_transmit_cmd(chip, &tpm_cmd,
1035 TPM_GETRANDOM_RESULT_SIZE + num_bytes,
1036 0, "attempting get random");
1040 recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
1041 memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
1046 } while (retries-- && total < max);
1049 return total ? total : -EIO;
1051 EXPORT_SYMBOL_GPL(tpm_get_random);
1054 * tpm_seal_trusted() - seal a trusted key
1055 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1056 * @options: authentication values and other options
1057 * @payload: the key data in clear and encrypted form
1059 * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips
1062 int tpm_seal_trusted(u32 chip_num, struct trusted_key_payload *payload,
1063 struct trusted_key_options *options)
1065 struct tpm_chip *chip;
1068 chip = tpm_chip_find_get(chip_num);
1069 if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1072 rc = tpm2_seal_trusted(chip, payload, options);
1077 EXPORT_SYMBOL_GPL(tpm_seal_trusted);
1080 * tpm_unseal_trusted() - unseal a trusted key
1081 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1082 * @options: authentication values and other options
1083 * @payload: the key data in clear and encrypted form
1085 * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips
1088 int tpm_unseal_trusted(u32 chip_num, struct trusted_key_payload *payload,
1089 struct trusted_key_options *options)
1091 struct tpm_chip *chip;
1094 chip = tpm_chip_find_get(chip_num);
1095 if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1098 rc = tpm2_unseal_trusted(chip, payload, options);
1103 EXPORT_SYMBOL_GPL(tpm_unseal_trusted);
1105 static int __init tpm_init(void)
1109 tpm_class = class_create(THIS_MODULE, "tpm");
1110 if (IS_ERR(tpm_class)) {
1111 pr_err("couldn't create tpm class\n");
1112 return PTR_ERR(tpm_class);
1115 rc = alloc_chrdev_region(&tpm_devt, 0, TPM_NUM_DEVICES, "tpm");
1117 pr_err("tpm: failed to allocate char dev region\n");
1118 class_destroy(tpm_class);
1125 static void __exit tpm_exit(void)
1127 class_destroy(tpm_class);
1128 unregister_chrdev_region(tpm_devt, TPM_NUM_DEVICES);
1131 subsys_initcall(tpm_init);
1132 module_exit(tpm_exit);
1134 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1135 MODULE_DESCRIPTION("TPM Driver");
1136 MODULE_VERSION("2.0");
1137 MODULE_LICENSE("GPL");