/* * Copyright (C) 2004 IBM Corporation * Copyright (C) 2014 Intel Corporation * * Authors: * Leendert van Doorn * Dave Safford * Reiner Sailer * Kylene Hall * * Maintained by: * * Device driver for TCG/TCPA TPM (trusted platform module). * Specifications at www.trustedcomputinggroup.org * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation, version 2 of the * License. * * Note, the TPM chip is not interrupt driven (only polling) * and can have very long timeouts (minutes!). Hence the unusual * calls to msleep. * */ #include #include #include #include #include #include #include "tpm.h" #define TPM_MAX_ORDINAL 243 #define TSC_MAX_ORDINAL 12 #define TPM_PROTECTED_COMMAND 0x00 #define TPM_CONNECTION_COMMAND 0x40 /* * Bug workaround - some TPM's don't flush the most * recently changed pcr on suspend, so force the flush * with an extend to the selected _unused_ non-volatile pcr. */ static int tpm_suspend_pcr; module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644); MODULE_PARM_DESC(suspend_pcr, "PCR to use for dummy writes to facilitate flush on suspend."); /* * Array with one entry per ordinal defining the maximum amount * of time the chip could take to return the result. The ordinal * designation of short, medium or long is defined in a table in * TCG Specification TPM Main Part 2 TPM Structures Section 17. The * values of the SHORT, MEDIUM, and LONG durations are retrieved * from the chip during initialization with a call to tpm_get_timeouts. */ static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = { TPM_UNDEFINED, /* 0 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, /* 5 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_SHORT, /* 10 */ TPM_SHORT, TPM_MEDIUM, TPM_LONG, TPM_LONG, TPM_MEDIUM, /* 15 */ TPM_SHORT, TPM_SHORT, TPM_MEDIUM, TPM_LONG, TPM_SHORT, /* 20 */ TPM_SHORT, TPM_MEDIUM, TPM_MEDIUM, TPM_MEDIUM, TPM_SHORT, /* 25 */ TPM_SHORT, TPM_MEDIUM, TPM_SHORT, TPM_SHORT, TPM_MEDIUM, /* 30 */ TPM_LONG, TPM_MEDIUM, TPM_SHORT, TPM_SHORT, TPM_SHORT, /* 35 */ TPM_MEDIUM, TPM_MEDIUM, TPM_UNDEFINED, TPM_UNDEFINED, TPM_MEDIUM, /* 40 */ TPM_LONG, TPM_MEDIUM, TPM_SHORT, TPM_SHORT, TPM_SHORT, /* 45 */ TPM_SHORT, TPM_SHORT, TPM_SHORT, TPM_LONG, TPM_MEDIUM, /* 50 */ TPM_MEDIUM, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, /* 55 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_MEDIUM, /* 60 */ TPM_MEDIUM, TPM_MEDIUM, TPM_SHORT, TPM_SHORT, TPM_MEDIUM, /* 65 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_SHORT, /* 70 */ TPM_SHORT, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, /* 75 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_LONG, /* 80 */ TPM_UNDEFINED, TPM_MEDIUM, TPM_LONG, TPM_SHORT, TPM_UNDEFINED, /* 85 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_SHORT, /* 90 */ TPM_SHORT, TPM_SHORT, TPM_SHORT, TPM_SHORT, TPM_UNDEFINED, /* 95 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_MEDIUM, /* 100 */ TPM_SHORT, TPM_SHORT, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, /* 105 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_SHORT, /* 110 */ TPM_SHORT, TPM_SHORT, TPM_SHORT, TPM_SHORT, TPM_SHORT, /* 115 */ TPM_SHORT, TPM_SHORT, TPM_UNDEFINED, TPM_UNDEFINED, TPM_LONG, /* 120 */ TPM_LONG, TPM_MEDIUM, TPM_UNDEFINED, TPM_SHORT, TPM_SHORT, /* 125 */ TPM_SHORT, TPM_LONG, TPM_SHORT, TPM_SHORT, TPM_SHORT, /* 130 */ TPM_MEDIUM, TPM_UNDEFINED, TPM_SHORT, TPM_MEDIUM, TPM_UNDEFINED, /* 135 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_SHORT, /* 140 */ TPM_SHORT, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, /* 145 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_SHORT, /* 150 */ TPM_MEDIUM, TPM_MEDIUM, TPM_SHORT, TPM_SHORT, TPM_UNDEFINED, /* 155 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_SHORT, /* 160 */ TPM_SHORT, TPM_SHORT, TPM_SHORT, TPM_UNDEFINED, TPM_UNDEFINED, /* 165 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_LONG, /* 170 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, /* 175 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_MEDIUM, /* 180 */ TPM_SHORT, TPM_MEDIUM, TPM_MEDIUM, TPM_MEDIUM, TPM_MEDIUM, /* 185 */ TPM_SHORT, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, /* 190 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, /* 195 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_SHORT, /* 200 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_SHORT, TPM_SHORT, /* 205 */ TPM_SHORT, TPM_SHORT, TPM_SHORT, TPM_SHORT, TPM_MEDIUM, /* 210 */ TPM_UNDEFINED, TPM_MEDIUM, TPM_MEDIUM, TPM_MEDIUM, TPM_UNDEFINED, /* 215 */ TPM_MEDIUM, TPM_UNDEFINED, TPM_UNDEFINED, TPM_SHORT, TPM_SHORT, /* 220 */ TPM_SHORT, TPM_SHORT, TPM_SHORT, TPM_SHORT, TPM_UNDEFINED, /* 225 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_SHORT, /* 230 */ TPM_LONG, TPM_MEDIUM, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, /* 235 */ TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_UNDEFINED, TPM_SHORT, /* 240 */ TPM_UNDEFINED, TPM_MEDIUM, }; /* * Returns max number of jiffies to wait */ unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal) { int duration_idx = TPM_UNDEFINED; int duration = 0; /* * We only have a duration table for protected commands, where the upper * 16 bits are 0. For the few other ordinals the fallback will be used. */ if (ordinal < TPM_MAX_ORDINAL) duration_idx = tpm_ordinal_duration[ordinal]; if (duration_idx != TPM_UNDEFINED) duration = chip->duration[duration_idx]; if (duration <= 0) return 2 * 60 * HZ; else return duration; } EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration); static int tpm_validate_command(struct tpm_chip *chip, struct tpm_space *space, const u8 *cmd, size_t len) { const struct tpm_input_header *header = (const void *)cmd; int i; u32 cc; u32 attrs; unsigned int nr_handles; if (len < TPM_HEADER_SIZE) return -EINVAL; if (!space) return 0; if (chip->flags & TPM_CHIP_FLAG_TPM2 && chip->nr_commands) { cc = be32_to_cpu(header->ordinal); i = tpm2_find_cc(chip, cc); if (i < 0) { dev_dbg(&chip->dev, "0x%04X is an invalid command\n", cc); return -EOPNOTSUPP; } attrs = chip->cc_attrs_tbl[i]; nr_handles = 4 * ((attrs >> TPM2_CC_ATTR_CHANDLES) & GENMASK(2, 0)); if (len < TPM_HEADER_SIZE + 4 * nr_handles) goto err_len; } return 0; err_len: dev_dbg(&chip->dev, "%s: insufficient command length %zu", __func__, len); return -EINVAL; } static int tpm_request_locality(struct tpm_chip *chip, unsigned int flags) { int rc; if (flags & TPM_TRANSMIT_NESTED) return 0; if (!chip->ops->request_locality) return 0; rc = chip->ops->request_locality(chip, 0); if (rc < 0) return rc; chip->locality = rc; return 0; } static void tpm_relinquish_locality(struct tpm_chip *chip, unsigned int flags) { int rc; if (flags & TPM_TRANSMIT_NESTED) return; if (!chip->ops->relinquish_locality) return; rc = chip->ops->relinquish_locality(chip, chip->locality); if (rc) dev_err(&chip->dev, "%s: : error %d\n", __func__, rc); chip->locality = -1; } static int tpm_cmd_ready(struct tpm_chip *chip, unsigned int flags) { if (flags & TPM_TRANSMIT_NESTED) return 0; if (!chip->ops->cmd_ready) return 0; return chip->ops->cmd_ready(chip); } static int tpm_go_idle(struct tpm_chip *chip, unsigned int flags) { if (flags & TPM_TRANSMIT_NESTED) return 0; if (!chip->ops->go_idle) return 0; return chip->ops->go_idle(chip); } static ssize_t tpm_try_transmit(struct tpm_chip *chip, struct tpm_space *space, u8 *buf, size_t bufsiz, unsigned int flags) { struct tpm_output_header *header = (void *)buf; int rc; ssize_t len = 0; u32 count, ordinal; unsigned long stop; bool need_locality; rc = tpm_validate_command(chip, space, buf, bufsiz); if (rc == -EINVAL) return rc; /* * If the command is not implemented by the TPM, synthesize a * response with a TPM2_RC_COMMAND_CODE return for user-space. */ if (rc == -EOPNOTSUPP) { header->length = cpu_to_be32(sizeof(*header)); header->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS); header->return_code = cpu_to_be32(TPM2_RC_COMMAND_CODE | TSS2_RESMGR_TPM_RC_LAYER); return sizeof(*header); } if (bufsiz > TPM_BUFSIZE) bufsiz = TPM_BUFSIZE; count = be32_to_cpu(*((__be32 *) (buf + 2))); ordinal = be32_to_cpu(*((__be32 *) (buf + 6))); if (count == 0) return -ENODATA; if (count > bufsiz) { dev_err(&chip->dev, "invalid count value %x %zx\n", count, bufsiz); return -E2BIG; } if (!(flags & TPM_TRANSMIT_UNLOCKED) && !(flags & TPM_TRANSMIT_NESTED)) mutex_lock(&chip->tpm_mutex); if (chip->ops->clk_enable != NULL) chip->ops->clk_enable(chip, true); /* Store the decision as chip->locality will be changed. */ need_locality = chip->locality == -1; if (need_locality) { rc = tpm_request_locality(chip, flags); if (rc < 0) { need_locality = false; goto out_locality; } } rc = tpm_cmd_ready(chip, flags); if (rc) goto out_locality; rc = tpm2_prepare_space(chip, space, ordinal, buf); if (rc) goto out; rc = chip->ops->send(chip, buf, count); if (rc < 0) { if (rc != -EPIPE) dev_err(&chip->dev, "%s: tpm_send: error %d\n", __func__, rc); goto out; } if (chip->flags & TPM_CHIP_FLAG_IRQ) goto out_recv; if (chip->flags & TPM_CHIP_FLAG_TPM2) stop = jiffies + tpm2_calc_ordinal_duration(chip, ordinal); else stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal); do { u8 status = chip->ops->status(chip); if ((status & chip->ops->req_complete_mask) == chip->ops->req_complete_val) goto out_recv; if (chip->ops->req_canceled(chip, status)) { dev_err(&chip->dev, "Operation Canceled\n"); rc = -ECANCELED; goto out; } tpm_msleep(TPM_TIMEOUT_POLL); rmb(); } while (time_before(jiffies, stop)); chip->ops->cancel(chip); dev_err(&chip->dev, "Operation Timed out\n"); rc = -ETIME; goto out; out_recv: len = chip->ops->recv(chip, buf, bufsiz); if (len < 0) { rc = len; dev_err(&chip->dev, "tpm_transmit: tpm_recv: error %d\n", rc); goto out; } else if (len < TPM_HEADER_SIZE) { rc = -EFAULT; goto out; } if (len != be32_to_cpu(header->length)) { rc = -EFAULT; goto out; } rc = tpm2_commit_space(chip, space, ordinal, buf, &len); if (rc) dev_err(&chip->dev, "tpm2_commit_space: error %d\n", rc); out: /* may fail but do not override previous error value in rc */ tpm_go_idle(chip, flags); out_locality: if (need_locality) tpm_relinquish_locality(chip, flags); if (chip->ops->clk_enable != NULL) chip->ops->clk_enable(chip, false); if (!(flags & TPM_TRANSMIT_UNLOCKED) && !(flags & TPM_TRANSMIT_NESTED)) mutex_unlock(&chip->tpm_mutex); return rc ? rc : len; } /** * tpm_transmit - Internal kernel interface to transmit TPM commands. * * @chip: TPM chip to use * @space: tpm space * @buf: TPM command buffer * @bufsiz: length of the TPM command buffer * @flags: tpm transmit flags - bitmap * * A wrapper around tpm_try_transmit that handles TPM2_RC_RETRY * returns from the TPM and retransmits the command after a delay up * to a maximum wait of TPM2_DURATION_LONG. * * Note: TPM1 never returns TPM2_RC_RETRY so the retry logic is TPM2 * only * * Return: * the length of the return when the operation is successful. * A negative number for system errors (errno). */ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space, u8 *buf, size_t bufsiz, unsigned int flags) { struct tpm_output_header *header = (struct tpm_output_header *)buf; /* space for header and handles */ u8 save[TPM_HEADER_SIZE + 3*sizeof(u32)]; unsigned int delay_msec = TPM2_DURATION_SHORT; u32 rc = 0; ssize_t ret; const size_t save_size = min(space ? sizeof(save) : TPM_HEADER_SIZE, bufsiz); /* the command code is where the return code will be */ u32 cc = be32_to_cpu(header->return_code); /* * Subtlety here: if we have a space, the handles will be * transformed, so when we restore the header we also have to * restore the handles. */ memcpy(save, buf, save_size); for (;;) { ret = tpm_try_transmit(chip, space, buf, bufsiz, flags); if (ret < 0) break; rc = be32_to_cpu(header->return_code); if (rc != TPM2_RC_RETRY && rc != TPM2_RC_TESTING) break; /* * return immediately if self test returns test * still running to shorten boot time. */ if (rc == TPM2_RC_TESTING && cc == TPM2_CC_SELF_TEST) break; if (delay_msec > TPM2_DURATION_LONG) { if (rc == TPM2_RC_RETRY) dev_err(&chip->dev, "in retry loop\n"); else dev_err(&chip->dev, "self test is still running\n"); break; } tpm_msleep(delay_msec); delay_msec *= 2; memcpy(buf, save, save_size); } return ret; } /** * tpm_transmit_cmd - send a tpm command to the device * The function extracts tpm out header return code * * @chip: TPM chip to use * @space: tpm space * @buf: TPM command buffer * @bufsiz: length of the buffer * @min_rsp_body_length: minimum expected length of response body * @flags: tpm transmit flags - bitmap * @desc: command description used in the error message * * Return: * 0 when the operation is successful. * A negative number for system errors (errno). * A positive number for a TPM error. */ ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_space *space, void *buf, size_t bufsiz, size_t min_rsp_body_length, unsigned int flags, const char *desc) { const struct tpm_output_header *header = buf; int err; ssize_t len; len = tpm_transmit(chip, space, buf, bufsiz, flags); if (len < 0) return len; err = be32_to_cpu(header->return_code); if (err != 0 && err != TPM_ERR_DISABLED && err != TPM_ERR_DEACTIVATED && desc) dev_err(&chip->dev, "A TPM error (%d) occurred %s\n", err, desc); if (err) return err; if (len < min_rsp_body_length + TPM_HEADER_SIZE) return -EFAULT; return 0; } EXPORT_SYMBOL_GPL(tpm_transmit_cmd); #define TPM_ORD_STARTUP 153 #define TPM_ST_CLEAR 1 /** * tpm_startup - turn on the TPM * @chip: TPM chip to use * * Normally the firmware should start the TPM. This function is provided as a * workaround if this does not happen. A legal case for this could be for * example when a TPM emulator is used. * * Return: same as tpm_transmit_cmd() */ int tpm_startup(struct tpm_chip *chip) { struct tpm_buf buf; int rc; dev_info(&chip->dev, "starting up the TPM manually\n"); if (chip->flags & TPM_CHIP_FLAG_TPM2) { rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_STARTUP); if (rc < 0) return rc; tpm_buf_append_u16(&buf, TPM2_SU_CLEAR); } else { rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_STARTUP); if (rc < 0) return rc; tpm_buf_append_u16(&buf, TPM_ST_CLEAR); } rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, "attempting to start the TPM"); tpm_buf_destroy(&buf); return rc; } #define TPM_DIGEST_SIZE 20 #define TPM_RET_CODE_IDX 6 #define TPM_INTERNAL_RESULT_SIZE 200 #define TPM_ORD_GET_CAP 101 #define TPM_ORD_GET_RANDOM 70 static const struct tpm_input_header tpm_getcap_header = { .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND), .length = cpu_to_be32(22), .ordinal = cpu_to_be32(TPM_ORD_GET_CAP) }; ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap, const char *desc, size_t min_cap_length) { struct tpm_buf buf; int rc; rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_CAP); if (rc) return rc; if (subcap_id == TPM_CAP_VERSION_1_1 || subcap_id == TPM_CAP_VERSION_1_2) { tpm_buf_append_u32(&buf, subcap_id); tpm_buf_append_u32(&buf, 0); } else { if (subcap_id == TPM_CAP_FLAG_PERM || subcap_id == TPM_CAP_FLAG_VOL) tpm_buf_append_u32(&buf, TPM_CAP_FLAG); else tpm_buf_append_u32(&buf, TPM_CAP_PROP); tpm_buf_append_u32(&buf, 4); tpm_buf_append_u32(&buf, subcap_id); } rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, min_cap_length, 0, desc); if (!rc) *cap = *(cap_t *)&buf.data[TPM_HEADER_SIZE + 4]; tpm_buf_destroy(&buf); return rc; } EXPORT_SYMBOL_GPL(tpm_getcap); int tpm_get_timeouts(struct tpm_chip *chip) { cap_t cap; unsigned long timeout_old[4], timeout_chip[4], timeout_eff[4]; ssize_t rc; if (chip->flags & TPM_CHIP_FLAG_HAVE_TIMEOUTS) return 0; if (chip->flags & TPM_CHIP_FLAG_TPM2) { /* Fixed timeouts for TPM2 */ chip->timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A); chip->timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B); chip->timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C); chip->timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D); chip->duration[TPM_SHORT] = msecs_to_jiffies(TPM2_DURATION_SHORT); chip->duration[TPM_MEDIUM] = msecs_to_jiffies(TPM2_DURATION_MEDIUM); chip->duration[TPM_LONG] = msecs_to_jiffies(TPM2_DURATION_LONG); chip->duration[TPM_LONG_LONG] = msecs_to_jiffies(TPM2_DURATION_LONG_LONG); chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS; return 0; } rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, NULL, sizeof(cap.timeout)); if (rc == TPM_ERR_INVALID_POSTINIT) { if (tpm_startup(chip)) return rc; rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, "attempting to determine the timeouts", sizeof(cap.timeout)); } if (rc) { dev_err(&chip->dev, "A TPM error (%zd) occurred attempting to determine the timeouts\n", rc); return rc; } timeout_old[0] = jiffies_to_usecs(chip->timeout_a); timeout_old[1] = jiffies_to_usecs(chip->timeout_b); timeout_old[2] = jiffies_to_usecs(chip->timeout_c); timeout_old[3] = jiffies_to_usecs(chip->timeout_d); timeout_chip[0] = be32_to_cpu(cap.timeout.a); timeout_chip[1] = be32_to_cpu(cap.timeout.b); timeout_chip[2] = be32_to_cpu(cap.timeout.c); timeout_chip[3] = be32_to_cpu(cap.timeout.d); memcpy(timeout_eff, timeout_chip, sizeof(timeout_eff)); /* * Provide ability for vendor overrides of timeout values in case * of misreporting. */ if (chip->ops->update_timeouts != NULL) chip->timeout_adjusted = chip->ops->update_timeouts(chip, timeout_eff); if (!chip->timeout_adjusted) { /* Restore default if chip reported 0 */ int i; for (i = 0; i < ARRAY_SIZE(timeout_eff); i++) { if (timeout_eff[i]) continue; timeout_eff[i] = timeout_old[i]; chip->timeout_adjusted = true; } if (timeout_eff[0] != 0 && timeout_eff[0] < 1000) { /* timeouts in msec rather usec */ for (i = 0; i != ARRAY_SIZE(timeout_eff); i++) timeout_eff[i] *= 1000; chip->timeout_adjusted = true; } } /* Report adjusted timeouts */ if (chip->timeout_adjusted) { dev_info(&chip->dev, HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n", timeout_chip[0], timeout_eff[0], timeout_chip[1], timeout_eff[1], timeout_chip[2], timeout_eff[2], timeout_chip[3], timeout_eff[3]); } chip->timeout_a = usecs_to_jiffies(timeout_eff[0]); chip->timeout_b = usecs_to_jiffies(timeout_eff[1]); chip->timeout_c = usecs_to_jiffies(timeout_eff[2]); chip->timeout_d = usecs_to_jiffies(timeout_eff[3]); rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap, "attempting to determine the durations", sizeof(cap.duration)); if (rc) return rc; chip->duration[TPM_SHORT] = usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short)); chip->duration[TPM_MEDIUM] = usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium)); chip->duration[TPM_LONG] = usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long)); chip->duration[TPM_LONG_LONG] = 0; /* not used under 1.2 */ /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above * value wrong and apparently reports msecs rather than usecs. So we * fix up the resulting too-small TPM_SHORT value to make things work. * We also scale the TPM_MEDIUM and -_LONG values by 1000. */ if (chip->duration[TPM_SHORT] < (HZ / 100)) { chip->duration[TPM_SHORT] = HZ; chip->duration[TPM_MEDIUM] *= 1000; chip->duration[TPM_LONG] *= 1000; chip->duration_adjusted = true; dev_info(&chip->dev, "Adjusting TPM timeout parameters."); } chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS; return 0; } EXPORT_SYMBOL_GPL(tpm_get_timeouts); #define TPM_ORD_CONTINUE_SELFTEST 83 #define CONTINUE_SELFTEST_RESULT_SIZE 10 static const struct tpm_input_header continue_selftest_header = { .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND), .length = cpu_to_be32(10), .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST), }; /** * tpm_continue_selftest -- run TPM's selftest * @chip: TPM chip to use * * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing * a TPM error code. */ static int tpm_continue_selftest(struct tpm_chip *chip) { int rc; struct tpm_cmd_t cmd; cmd.header.in = continue_selftest_header; rc = tpm_transmit_cmd(chip, NULL, &cmd, CONTINUE_SELFTEST_RESULT_SIZE, 0, 0, "continue selftest"); return rc; } #define TPM_ORDINAL_PCRREAD 21 #define READ_PCR_RESULT_SIZE 30 #define READ_PCR_RESULT_BODY_SIZE 20 static const struct tpm_input_header pcrread_header = { .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND), .length = cpu_to_be32(14), .ordinal = cpu_to_be32(TPM_ORDINAL_PCRREAD) }; int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) { int rc; struct tpm_cmd_t cmd; cmd.header.in = pcrread_header; cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx); rc = tpm_transmit_cmd(chip, NULL, &cmd, READ_PCR_RESULT_SIZE, READ_PCR_RESULT_BODY_SIZE, 0, "attempting to read a pcr value"); if (rc == 0) memcpy(res_buf, cmd.params.pcrread_out.pcr_result, TPM_DIGEST_SIZE); return rc; } /** * tpm_is_tpm2 - do we a have a TPM2 chip? * @chip: a &struct tpm_chip instance, %NULL for the default chip * * Return: * 1 if we have a TPM2 chip. * 0 if we don't have a TPM2 chip. * A negative number for system errors (errno). */ int tpm_is_tpm2(struct tpm_chip *chip) { int rc; chip = tpm_find_get_ops(chip); if (!chip) return -ENODEV; rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0; tpm_put_ops(chip); return rc; } EXPORT_SYMBOL_GPL(tpm_is_tpm2); /** * tpm_pcr_read - read a PCR value from SHA1 bank * @chip: a &struct tpm_chip instance, %NULL for the default chip * @pcr_idx: the PCR to be retrieved * @res_buf: the value of the PCR * * Return: same as with tpm_transmit_cmd() */ int tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) { int rc; chip = tpm_find_get_ops(chip); if (!chip) return -ENODEV; if (chip->flags & TPM_CHIP_FLAG_TPM2) rc = tpm2_pcr_read(chip, pcr_idx, res_buf); else rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf); tpm_put_ops(chip); return rc; } EXPORT_SYMBOL_GPL(tpm_pcr_read); #define TPM_ORD_PCR_EXTEND 20 #define EXTEND_PCR_RESULT_SIZE 34 #define EXTEND_PCR_RESULT_BODY_SIZE 20 static const struct tpm_input_header pcrextend_header = { .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND), .length = cpu_to_be32(34), .ordinal = cpu_to_be32(TPM_ORD_PCR_EXTEND) }; static int tpm1_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash, char *log_msg) { struct tpm_buf buf; int rc; rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_PCR_EXTEND); if (rc) return rc; tpm_buf_append_u32(&buf, pcr_idx); tpm_buf_append(&buf, hash, TPM_DIGEST_SIZE); rc = tpm_transmit_cmd(chip, NULL, buf.data, EXTEND_PCR_RESULT_SIZE, EXTEND_PCR_RESULT_BODY_SIZE, 0, log_msg); tpm_buf_destroy(&buf); return rc; } /** * tpm_pcr_extend - extend a PCR value in SHA1 bank. * @chip: a &struct tpm_chip instance, %NULL for the default chip * @pcr_idx: the PCR to be retrieved * @hash: the hash value used to extend the PCR value * * Note: with TPM 2.0 extends also those banks with a known digest size to the * cryto subsystem in order to prevent malicious use of those PCR banks. In the * future we should dynamically determine digest sizes. * * Return: same as with tpm_transmit_cmd() */ int tpm_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash) { int rc; struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)]; u32 count = 0; int i; chip = tpm_find_get_ops(chip); if (!chip) return -ENODEV; if (chip->flags & TPM_CHIP_FLAG_TPM2) { memset(digest_list, 0, sizeof(digest_list)); for (i = 0; i < ARRAY_SIZE(chip->active_banks) && chip->active_banks[i] != TPM2_ALG_ERROR; i++) { digest_list[i].alg_id = chip->active_banks[i]; memcpy(digest_list[i].digest, hash, TPM_DIGEST_SIZE); count++; } rc = tpm2_pcr_extend(chip, pcr_idx, count, digest_list); tpm_put_ops(chip); return rc; } rc = tpm1_pcr_extend(chip, pcr_idx, hash, "attempting extend a PCR value"); tpm_put_ops(chip); return rc; } EXPORT_SYMBOL_GPL(tpm_pcr_extend); /** * tpm_do_selftest - have the TPM continue its selftest and wait until it * can receive further commands * @chip: TPM chip to use * * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing * a TPM error code. */ int tpm_do_selftest(struct tpm_chip *chip) { int rc; unsigned int loops; unsigned int delay_msec = 100; unsigned long duration; u8 dummy[TPM_DIGEST_SIZE]; duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST); loops = jiffies_to_msecs(duration) / delay_msec; rc = tpm_continue_selftest(chip); if (rc == TPM_ERR_INVALID_POSTINIT) { chip->flags |= TPM_CHIP_FLAG_ALWAYS_POWERED; dev_info(&chip->dev, "TPM not ready (%d)\n", rc); } /* This may fail if there was no TPM driver during a suspend/resume * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST) */ if (rc) return rc; do { /* Attempt to read a PCR value */ rc = tpm_pcr_read_dev(chip, 0, dummy); /* Some buggy TPMs will not respond to tpm_tis_ready() for * around 300ms while the self test is ongoing, keep trying * until the self test duration expires. */ if (rc == -ETIME) { dev_info( &chip->dev, HW_ERR "TPM command timed out during continue self test"); tpm_msleep(delay_msec); continue; } if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) { dev_info(&chip->dev, "TPM is disabled/deactivated (0x%X)\n", rc); /* TPM is disabled and/or deactivated; driver can * proceed and TPM does handle commands for * suspend/resume correctly */ return 0; } if (rc != TPM_WARN_DOING_SELFTEST) return rc; tpm_msleep(delay_msec); } while (--loops > 0); return rc; } EXPORT_SYMBOL_GPL(tpm_do_selftest); /** * tpm1_auto_startup - Perform the standard automatic TPM initialization * sequence * @chip: TPM chip to use * * Returns 0 on success, < 0 in case of fatal error. */ int tpm1_auto_startup(struct tpm_chip *chip) { int rc; rc = tpm_get_timeouts(chip); if (rc) goto out; rc = tpm_do_selftest(chip); if (rc) { dev_err(&chip->dev, "TPM self test failed\n"); goto out; } return rc; out: if (rc > 0) rc = -ENODEV; return rc; } /** * tpm_send - send a TPM command * @chip: a &struct tpm_chip instance, %NULL for the default chip * @cmd: a TPM command buffer * @buflen: the length of the TPM command buffer * * Return: same as with tpm_transmit_cmd() */ int tpm_send(struct tpm_chip *chip, void *cmd, size_t buflen) { int rc; chip = tpm_find_get_ops(chip); if (!chip) return -ENODEV; rc = tpm_transmit_cmd(chip, NULL, cmd, buflen, 0, 0, "attempting to a send a command"); tpm_put_ops(chip); return rc; } EXPORT_SYMBOL_GPL(tpm_send); #define TPM_ORD_SAVESTATE 152 #define SAVESTATE_RESULT_SIZE 10 static const struct tpm_input_header savestate_header = { .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND), .length = cpu_to_be32(10), .ordinal = cpu_to_be32(TPM_ORD_SAVESTATE) }; /* * We are about to suspend. Save the TPM state * so that it can be restored. */ int tpm_pm_suspend(struct device *dev) { struct tpm_chip *chip = dev_get_drvdata(dev); struct tpm_cmd_t cmd; int rc, try; u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 }; if (chip == NULL) return -ENODEV; if (chip->flags & TPM_CHIP_FLAG_ALWAYS_POWERED) return 0; if (chip->flags & TPM_CHIP_FLAG_TPM2) { tpm2_shutdown(chip, TPM2_SU_STATE); return 0; } /* for buggy tpm, flush pcrs with extend to selected dummy */ if (tpm_suspend_pcr) rc = tpm1_pcr_extend(chip, tpm_suspend_pcr, dummy_hash, "extending dummy pcr before suspend"); /* now do the actual savestate */ for (try = 0; try < TPM_RETRY; try++) { cmd.header.in = savestate_header; rc = tpm_transmit_cmd(chip, NULL, &cmd, SAVESTATE_RESULT_SIZE, 0, 0, NULL); /* * If the TPM indicates that it is too busy to respond to * this command then retry before giving up. It can take * several seconds for this TPM to be ready. * * This can happen if the TPM has already been sent the * SaveState command before the driver has loaded. TCG 1.2 * specification states that any communication after SaveState * may cause the TPM to invalidate previously saved state. */ if (rc != TPM_WARN_RETRY) break; tpm_msleep(TPM_TIMEOUT_RETRY); } if (rc) dev_err(&chip->dev, "Error (%d) sending savestate before suspend\n", rc); else if (try > 0) dev_warn(&chip->dev, "TPM savestate took %dms\n", try * TPM_TIMEOUT_RETRY); return rc; } EXPORT_SYMBOL_GPL(tpm_pm_suspend); /* * Resume from a power safe. The BIOS already restored * the TPM state. */ int tpm_pm_resume(struct device *dev) { struct tpm_chip *chip = dev_get_drvdata(dev); if (chip == NULL) return -ENODEV; return 0; } EXPORT_SYMBOL_GPL(tpm_pm_resume); #define TPM_GETRANDOM_RESULT_SIZE 18 static const struct tpm_input_header tpm_getrandom_header = { .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND), .length = cpu_to_be32(14), .ordinal = cpu_to_be32(TPM_ORD_GET_RANDOM) }; /** * tpm_get_random() - get random bytes from the TPM's RNG * @chip: a &struct tpm_chip instance, %NULL for the default chip * @out: destination buffer for the random bytes * @max: the max number of bytes to write to @out * * Return: same as with tpm_transmit_cmd() */ int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max) { struct tpm_cmd_t tpm_cmd; u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA), rlength; int err, total = 0, retries = 5; u8 *dest = out; if (!out || !num_bytes || max > TPM_MAX_RNG_DATA) return -EINVAL; chip = tpm_find_get_ops(chip); if (!chip) return -ENODEV; if (chip->flags & TPM_CHIP_FLAG_TPM2) { err = tpm2_get_random(chip, out, max); tpm_put_ops(chip); return err; } do { tpm_cmd.header.in = tpm_getrandom_header; tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes); err = tpm_transmit_cmd(chip, NULL, &tpm_cmd, TPM_GETRANDOM_RESULT_SIZE + num_bytes, offsetof(struct tpm_getrandom_out, rng_data), 0, "attempting get random"); if (err) break; recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len); if (recd > num_bytes) { total = -EFAULT; break; } rlength = be32_to_cpu(tpm_cmd.header.out.length); if (rlength < TPM_HEADER_SIZE + offsetof(struct tpm_getrandom_out, rng_data) + recd) { total = -EFAULT; break; } memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd); dest += recd; total += recd; num_bytes -= recd; } while (retries-- && total < max); tpm_put_ops(chip); return total ? total : -EIO; } EXPORT_SYMBOL_GPL(tpm_get_random); /** * tpm_seal_trusted() - seal a trusted key payload * @chip: a &struct tpm_chip instance, %NULL for the default chip * @options: authentication values and other options * @payload: the key data in clear and encrypted form * * Note: only TPM 2.0 chip are supported. TPM 1.x implementation is located in * the keyring subsystem. * * Return: same as with tpm_transmit_cmd() */ int tpm_seal_trusted(struct tpm_chip *chip, struct trusted_key_payload *payload, struct trusted_key_options *options) { int rc; chip = tpm_find_get_ops(chip); if (!chip || !(chip->flags & TPM_CHIP_FLAG_TPM2)) return -ENODEV; rc = tpm2_seal_trusted(chip, payload, options); tpm_put_ops(chip); return rc; } EXPORT_SYMBOL_GPL(tpm_seal_trusted); /** * tpm_unseal_trusted() - unseal a trusted key * @chip: a &struct tpm_chip instance, %NULL for the default chip * @options: authentication values and other options * @payload: the key data in clear and encrypted form * * Note: only TPM 2.0 chip are supported. TPM 1.x implementation is located in * the keyring subsystem. * * Return: same as with tpm_transmit_cmd() */ int tpm_unseal_trusted(struct tpm_chip *chip, struct trusted_key_payload *payload, struct trusted_key_options *options) { int rc; chip = tpm_find_get_ops(chip); if (!chip || !(chip->flags & TPM_CHIP_FLAG_TPM2)) return -ENODEV; rc = tpm2_unseal_trusted(chip, payload, options); tpm_put_ops(chip); return rc; } EXPORT_SYMBOL_GPL(tpm_unseal_trusted); static int __init tpm_init(void) { int rc; tpm_class = class_create(THIS_MODULE, "tpm"); if (IS_ERR(tpm_class)) { pr_err("couldn't create tpm class\n"); return PTR_ERR(tpm_class); } tpmrm_class = class_create(THIS_MODULE, "tpmrm"); if (IS_ERR(tpmrm_class)) { pr_err("couldn't create tpmrm class\n"); class_destroy(tpm_class); return PTR_ERR(tpmrm_class); } rc = alloc_chrdev_region(&tpm_devt, 0, 2*TPM_NUM_DEVICES, "tpm"); if (rc < 0) { pr_err("tpm: failed to allocate char dev region\n"); class_destroy(tpmrm_class); class_destroy(tpm_class); return rc; } return 0; } static void __exit tpm_exit(void) { idr_destroy(&dev_nums_idr); class_destroy(tpm_class); class_destroy(tpmrm_class); unregister_chrdev_region(tpm_devt, 2*TPM_NUM_DEVICES); } subsys_initcall(tpm_init); module_exit(tpm_exit); MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)"); MODULE_DESCRIPTION("TPM Driver"); MODULE_VERSION("2.0"); MODULE_LICENSE("GPL");