linux/drivers/char/tpm/tpm-sysfs.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2004 IBM Corporation
 * Authors:
 * Leendert van Doorn <[email protected]>
 * Dave Safford <[email protected]>
 * Reiner Sailer <[email protected]>
 * Kylene Hall <[email protected]>
 *
 * Copyright (C) 2013 Obsidian Research Corp
 * Jason Gunthorpe <[email protected]>
 *
 * sysfs filesystem inspection interface to the TPM
 */
#include <linux/device.h>
#include "tpm.h"

struct tpm_readpubek_out { … } __packed;

#define READ_PUBEK_RESULT_MIN_BODY_SIZE …
#define TPM_ORD_READPUBEK …

static ssize_t pubek_show(struct device *dev, struct device_attribute *attr,
			  char *buf)
{ … }
static DEVICE_ATTR_RO(pubek);

static ssize_t pcrs_show(struct device *dev, struct device_attribute *attr,
			 char *buf)
{ … }
static DEVICE_ATTR_RO(pcrs);

static ssize_t enabled_show(struct device *dev, struct device_attribute *attr,
		     char *buf)
{ … }
static DEVICE_ATTR_RO(enabled);

static ssize_t active_show(struct device *dev, struct device_attribute *attr,
		    char *buf)
{ … }
static DEVICE_ATTR_RO(active);

static ssize_t owned_show(struct device *dev, struct device_attribute *attr,
			  char *buf)
{ … }
static DEVICE_ATTR_RO(owned);

static ssize_t temp_deactivated_show(struct device *dev,
				     struct device_attribute *attr, char *buf)
{ … }
static DEVICE_ATTR_RO(temp_deactivated);

static ssize_t caps_show(struct device *dev, struct device_attribute *attr,
			 char *buf)
{ … }
static DEVICE_ATTR_RO(caps);

static ssize_t cancel_store(struct device *dev, struct device_attribute *attr,
			    const char *buf, size_t count)
{ … }
static DEVICE_ATTR_WO(cancel);

static ssize_t durations_show(struct device *dev, struct device_attribute *attr,
			      char *buf)
{ … }
static DEVICE_ATTR_RO(durations);

static ssize_t timeouts_show(struct device *dev, struct device_attribute *attr,
			     char *buf)
{ … }
static DEVICE_ATTR_RO(timeouts);

static ssize_t tpm_version_major_show(struct device *dev,
				  struct device_attribute *attr, char *buf)
{ … }
static DEVICE_ATTR_RO(tpm_version_major);

#ifdef CONFIG_TCG_TPM2_HMAC
static ssize_t null_name_show(struct device *dev, struct device_attribute *attr,
			      char *buf)
{ … }
static DEVICE_ATTR_RO(null_name);
#endif

static struct attribute *tpm1_dev_attrs[] = …;

static struct attribute *tpm2_dev_attrs[] = …;

static const struct attribute_group tpm1_dev_group = …;

static const struct attribute_group tpm2_dev_group = …;

struct tpm_pcr_attr { … };

#define to_tpm_pcr_attr(a) …

static ssize_t pcr_value_show(struct device *dev,
			      struct device_attribute *attr,
			      char *buf)
{ … }

/*
 * The following set of defines represents all the magic to build
 * the per hash attribute groups for displaying each bank of PCRs.
 * The only slight problem with this approach is that every PCR is
 * hard coded to be present, so you don't know if an PCR is missing
 * until a cat of the file returns -EINVAL
 *
 * Also note you must ignore checkpatch warnings in this macro
 * code. This is deep macro magic that checkpatch.pl doesn't
 * understand.
 */

/* Note, this must match TPM2_PLATFORM_PCR which is fixed at 24. */
#define _TPM_HELPER(_alg, _hash, F) …

/* ignore checkpatch warning about trailing ; in macro. */
#define PCR_ATTR(_alg, _hash, _pcr) …

#define PCR_ATTRS(_alg, _hash) …

/* ignore checkpatch warning about trailing , in macro. */
#define PCR_ATTR_VAL(_alg, _hash, _pcr) …

#define PCR_ATTR_GROUP_ARRAY(_alg, _hash) …

#define PCR_ATTR_GROUP(_alg, _hash) …

#define PCR_ATTR_BUILD(_alg, _hash) …
/*
 * End of macro structure to build an attribute group containing 24
 * PCR value files for each supported hash algorithm
 */

/*
 * The next set of macros implements the cleverness for each hash to
 * build a static attribute group called pcr_group_<hash> which can be
 * added to chip->groups[].
 *
 * The first argument is the TPM algorithm id and the second is the
 * hash used as both the suffix and the group name.  Note: the group
 * name is a directory in the top level tpm class with the name
 * pcr-<hash>, so it must not clash with any other names already
 * in the sysfs directory.
 */
PCR_ATTR_BUILD(…);
PCR_ATTR_BUILD(…);
PCR_ATTR_BUILD(…);
PCR_ATTR_BUILD(…);
PCR_ATTR_BUILD(…);


void tpm_sysfs_add_device(struct tpm_chip *chip)
{ … }