linux/drivers/char/tpm/tpm1-cmd.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2004 IBM Corporation
 * Copyright (C) 2014 Intel Corporation
 *
 * Authors:
 * Leendert van Doorn <[email protected]>
 * Dave Safford <[email protected]>
 * Reiner Sailer <[email protected]>
 * Kylene Hall <[email protected]>
 *
 * Device driver for TCG/TCPA TPM (trusted platform module).
 * Specifications at www.trustedcomputinggroup.org
 */

#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/freezer.h>
#include <linux/tpm_eventlog.h>

#include "tpm.h"

#define TPM_MAX_ORDINAL …

/*
 * 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 tpm1_ordinal_duration[TPM_MAX_ORDINAL] = …;

/**
 * tpm1_calc_ordinal_duration() - calculate the maximum command duration
 * @chip:    TPM chip to use.
 * @ordinal: TPM command ordinal.
 *
 * The function returns the maximum amount of time the chip could take
 * to return the result for a particular ordinal in jiffies.
 *
 * Return: A maximal duration time for an ordinal in jiffies.
 */
unsigned long tpm1_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
{ … }

#define TPM_ORD_STARTUP …
#define TPM_ST_CLEAR …

/**
 * tpm1_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()
 */
static int tpm1_startup(struct tpm_chip *chip)
{ … }

int tpm1_get_timeouts(struct tpm_chip *chip)
{ … }

#define TPM_ORD_PCR_EXTEND …
int tpm1_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash,
		    const char *log_msg)
{ … }

#define TPM_ORD_GET_CAP …
ssize_t tpm1_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
		    const char *desc, size_t min_cap_length)
{ … }
EXPORT_SYMBOL_GPL(…);

#define TPM_ORD_GET_RANDOM …
struct tpm1_get_random_out { … } __packed;

/**
 * tpm1_get_random() - get random bytes from the TPM's RNG
 * @chip:	a &struct tpm_chip instance
 * @dest:	destination buffer for the random bytes
 * @max:	the maximum number of bytes to write to @dest
 *
 * Return:
 * *  number of bytes read
 * * -errno (positive TPM return codes are masked to -EIO)
 */
int tpm1_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
{ … }

#define TPM_ORD_PCRREAD …
int tpm1_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf)
{ … }

#define TPM_ORD_CONTINUE_SELFTEST …
/**
 * tpm1_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 tpm1_continue_selftest(struct tpm_chip *chip)
{ … }

/**
 * tpm1_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 tpm1_do_selftest(struct tpm_chip *chip)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * 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)
{ … }

#define TPM_ORD_SAVESTATE …

/**
 * tpm1_pm_suspend() - pm suspend handler
 * @chip: TPM chip to use.
 * @tpm_suspend_pcr: flush pcr for buggy TPM chips.
 *
 * The functions saves the TPM state to be restored on resume.
 *
 * Return:
 * * 0 on success,
 * * < 0 on error.
 */
int tpm1_pm_suspend(struct tpm_chip *chip, u32 tpm_suspend_pcr)
{ … }

/**
 * tpm1_get_pcr_allocation() - initialize the allocated bank
 * @chip: TPM chip to use.
 *
 * The function initializes the SHA1 allocated bank to extend PCR
 *
 * Return:
 * * 0 on success,
 * * < 0 on error.
 */
int tpm1_get_pcr_allocation(struct tpm_chip *chip)
{ … }