acrn-kernel/drivers/char/tpm/tpm-sysfs.c

530 lines
13 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2004 IBM Corporation
* Authors:
* Leendert van Doorn <leendert@watson.ibm.com>
* Dave Safford <safford@watson.ibm.com>
* Reiner Sailer <sailer@watson.ibm.com>
* Kylene Hall <kjhall@us.ibm.com>
*
* Copyright (C) 2013 Obsidian Research Corp
* Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
*
* sysfs filesystem inspection interface to the TPM
*/
#include <linux/device.h>
#include "tpm.h"
struct tpm_readpubek_out {
u8 algorithm[4];
u8 encscheme[2];
u8 sigscheme[2];
__be32 paramsize;
u8 parameters[12];
__be32 keysize;
u8 modulus[256];
u8 checksum[20];
} __packed;
#define READ_PUBEK_RESULT_MIN_BODY_SIZE (28 + 256)
#define TPM_ORD_READPUBEK 124
static ssize_t pubek_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct tpm_buf tpm_buf;
struct tpm_readpubek_out *out;
int i;
char *str = buf;
struct tpm_chip *chip = to_tpm_chip(dev);
char anti_replay[20];
memset(&anti_replay, 0, sizeof(anti_replay));
if (tpm_try_get_ops(chip))
return 0;
if (tpm_buf_init(&tpm_buf, TPM_TAG_RQU_COMMAND, TPM_ORD_READPUBEK))
goto out_ops;
tpm_buf_append(&tpm_buf, anti_replay, sizeof(anti_replay));
if (tpm_transmit_cmd(chip, &tpm_buf, READ_PUBEK_RESULT_MIN_BODY_SIZE,
"attempting to read the PUBEK"))
goto out_buf;
out = (struct tpm_readpubek_out *)&tpm_buf.data[10];
str +=
sprintf(str,
"Algorithm: %4ph\n"
"Encscheme: %2ph\n"
"Sigscheme: %2ph\n"
"Parameters: %12ph\n"
"Modulus length: %d\n"
"Modulus:\n",
out->algorithm,
out->encscheme,
out->sigscheme,
out->parameters,
be32_to_cpu(out->keysize));
for (i = 0; i < 256; i += 16)
str += sprintf(str, "%16ph\n", &out->modulus[i]);
out_buf:
tpm_buf_destroy(&tpm_buf);
out_ops:
tpm_put_ops(chip);
return str - buf;
}
static DEVICE_ATTR_RO(pubek);
static ssize_t pcrs_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
cap_t cap;
u8 digest[TPM_DIGEST_SIZE];
u32 i, j, num_pcrs;
char *str = buf;
struct tpm_chip *chip = to_tpm_chip(dev);
if (tpm_try_get_ops(chip))
return 0;
if (tpm1_getcap(chip, TPM_CAP_PROP_PCR, &cap,
"attempting to determine the number of PCRS",
sizeof(cap.num_pcrs))) {
tpm_put_ops(chip);
return 0;
}
num_pcrs = be32_to_cpu(cap.num_pcrs);
for (i = 0; i < num_pcrs; i++) {
if (tpm1_pcr_read(chip, i, digest)) {
str = buf;
break;
}
str += sprintf(str, "PCR-%02d: ", i);
for (j = 0; j < TPM_DIGEST_SIZE; j++)
str += sprintf(str, "%02X ", digest[j]);
str += sprintf(str, "\n");
}
tpm_put_ops(chip);
return str - buf;
}
static DEVICE_ATTR_RO(pcrs);
static ssize_t enabled_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct tpm_chip *chip = to_tpm_chip(dev);
ssize_t rc = 0;
cap_t cap;
if (tpm_try_get_ops(chip))
return 0;
if (tpm1_getcap(chip, TPM_CAP_FLAG_PERM, &cap,
"attempting to determine the permanent enabled state",
sizeof(cap.perm_flags)))
goto out_ops;
rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
out_ops:
tpm_put_ops(chip);
return rc;
}
static DEVICE_ATTR_RO(enabled);
static ssize_t active_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct tpm_chip *chip = to_tpm_chip(dev);
ssize_t rc = 0;
cap_t cap;
if (tpm_try_get_ops(chip))
return 0;
if (tpm1_getcap(chip, TPM_CAP_FLAG_PERM, &cap,
"attempting to determine the permanent active state",
sizeof(cap.perm_flags)))
goto out_ops;
rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
out_ops:
tpm_put_ops(chip);
return rc;
}
static DEVICE_ATTR_RO(active);
static ssize_t owned_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct tpm_chip *chip = to_tpm_chip(dev);
ssize_t rc = 0;
cap_t cap;
if (tpm_try_get_ops(chip))
return 0;
if (tpm1_getcap(to_tpm_chip(dev), TPM_CAP_PROP_OWNER, &cap,
"attempting to determine the owner state",
sizeof(cap.owned)))
goto out_ops;
rc = sprintf(buf, "%d\n", cap.owned);
out_ops:
tpm_put_ops(chip);
return rc;
}
static DEVICE_ATTR_RO(owned);
static ssize_t temp_deactivated_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct tpm_chip *chip = to_tpm_chip(dev);
ssize_t rc = 0;
cap_t cap;
if (tpm_try_get_ops(chip))
return 0;
if (tpm1_getcap(to_tpm_chip(dev), TPM_CAP_FLAG_VOL, &cap,
"attempting to determine the temporary state",
sizeof(cap.stclear_flags)))
goto out_ops;
rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
out_ops:
tpm_put_ops(chip);
return rc;
}
static DEVICE_ATTR_RO(temp_deactivated);
static ssize_t caps_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct tpm_chip *chip = to_tpm_chip(dev);
struct tpm1_version *version;
ssize_t rc = 0;
char *str = buf;
cap_t cap;
if (tpm_try_get_ops(chip))
return 0;
if (tpm1_getcap(chip, TPM_CAP_PROP_MANUFACTURER, &cap,
"attempting to determine the manufacturer",
sizeof(cap.manufacturer_id)))
goto out_ops;
str += sprintf(str, "Manufacturer: 0x%x\n",
be32_to_cpu(cap.manufacturer_id));
/* TPM 1.2 */
if (!tpm1_getcap(chip, TPM_CAP_VERSION_1_2, &cap,
"attempting to determine the 1.2 version",
sizeof(cap.version2))) {
version = &cap.version2.version;
goto out_print;
}
/* TPM 1.1 */
if (tpm1_getcap(chip, TPM_CAP_VERSION_1_1, &cap,
"attempting to determine the 1.1 version",
sizeof(cap.version1))) {
goto out_ops;
}
version = &cap.version1;
out_print:
str += sprintf(str,
"TCG version: %d.%d\nFirmware version: %d.%d\n",
version->major, version->minor,
version->rev_major, version->rev_minor);
rc = str - buf;
out_ops:
tpm_put_ops(chip);
return rc;
}
static DEVICE_ATTR_RO(caps);
static ssize_t cancel_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct tpm_chip *chip = to_tpm_chip(dev);
if (tpm_try_get_ops(chip))
return 0;
chip->ops->cancel(chip);
tpm_put_ops(chip);
return count;
}
static DEVICE_ATTR_WO(cancel);
static ssize_t durations_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct tpm_chip *chip = to_tpm_chip(dev);
if (chip->duration[TPM_LONG] == 0)
return 0;
return sprintf(buf, "%d %d %d [%s]\n",
jiffies_to_usecs(chip->duration[TPM_SHORT]),
jiffies_to_usecs(chip->duration[TPM_MEDIUM]),
jiffies_to_usecs(chip->duration[TPM_LONG]),
chip->duration_adjusted
? "adjusted" : "original");
}
static DEVICE_ATTR_RO(durations);
static ssize_t timeouts_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct tpm_chip *chip = to_tpm_chip(dev);
return sprintf(buf, "%d %d %d %d [%s]\n",
jiffies_to_usecs(chip->timeout_a),
jiffies_to_usecs(chip->timeout_b),
jiffies_to_usecs(chip->timeout_c),
jiffies_to_usecs(chip->timeout_d),
chip->timeout_adjusted
? "adjusted" : "original");
}
static DEVICE_ATTR_RO(timeouts);
static ssize_t tpm_version_major_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct tpm_chip *chip = to_tpm_chip(dev);
return sprintf(buf, "%s\n", chip->flags & TPM_CHIP_FLAG_TPM2
? "2" : "1");
}
static DEVICE_ATTR_RO(tpm_version_major);
static struct attribute *tpm1_dev_attrs[] = {
&dev_attr_pubek.attr,
&dev_attr_pcrs.attr,
&dev_attr_enabled.attr,
&dev_attr_active.attr,
&dev_attr_owned.attr,
&dev_attr_temp_deactivated.attr,
&dev_attr_caps.attr,
&dev_attr_cancel.attr,
&dev_attr_durations.attr,
&dev_attr_timeouts.attr,
&dev_attr_tpm_version_major.attr,
NULL,
};
static struct attribute *tpm2_dev_attrs[] = {
&dev_attr_tpm_version_major.attr,
NULL
};
static const struct attribute_group tpm1_dev_group = {
.attrs = tpm1_dev_attrs,
};
static const struct attribute_group tpm2_dev_group = {
.attrs = tpm2_dev_attrs,
};
struct tpm_pcr_attr {
int alg_id;
int pcr;
struct device_attribute attr;
};
#define to_tpm_pcr_attr(a) container_of(a, struct tpm_pcr_attr, attr)
static ssize_t pcr_value_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct tpm_pcr_attr *ha = to_tpm_pcr_attr(attr);
struct tpm_chip *chip = to_tpm_chip(dev);
struct tpm_digest digest;
int i;
int digest_size = 0;
int rc;
char *str = buf;
for (i = 0; i < chip->nr_allocated_banks; i++)
if (ha->alg_id == chip->allocated_banks[i].alg_id)
digest_size = chip->allocated_banks[i].digest_size;
/* should never happen */
if (!digest_size)
return -EINVAL;
digest.alg_id = ha->alg_id;
rc = tpm_pcr_read(chip, ha->pcr, &digest);
if (rc)
return rc;
for (i = 0; i < digest_size; i++)
str += sprintf(str, "%02X", digest.digest[i]);
str += sprintf(str, "\n");
return str - 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) \
F(_alg, _hash, 0) \
F(_alg, _hash, 1) \
F(_alg, _hash, 2) \
F(_alg, _hash, 3) \
F(_alg, _hash, 4) \
F(_alg, _hash, 5) \
F(_alg, _hash, 6) \
F(_alg, _hash, 7) \
F(_alg, _hash, 8) \
F(_alg, _hash, 9) \
F(_alg, _hash, 10) \
F(_alg, _hash, 11) \
F(_alg, _hash, 12) \
F(_alg, _hash, 13) \
F(_alg, _hash, 14) \
F(_alg, _hash, 15) \
F(_alg, _hash, 16) \
F(_alg, _hash, 17) \
F(_alg, _hash, 18) \
F(_alg, _hash, 19) \
F(_alg, _hash, 20) \
F(_alg, _hash, 21) \
F(_alg, _hash, 22) \
F(_alg, _hash, 23)
/* ignore checkpatch warning about trailing ; in macro. */
#define PCR_ATTR(_alg, _hash, _pcr) \
static struct tpm_pcr_attr dev_attr_pcr_##_hash##_##_pcr = { \
.alg_id = _alg, \
.pcr = _pcr, \
.attr = { \
.attr = { \
.name = __stringify(_pcr), \
.mode = 0444 \
}, \
.show = pcr_value_show \
} \
};
#define PCR_ATTRS(_alg, _hash) \
_TPM_HELPER(_alg, _hash, PCR_ATTR)
/* ignore checkpatch warning about trailing , in macro. */
#define PCR_ATTR_VAL(_alg, _hash, _pcr) \
&dev_attr_pcr_##_hash##_##_pcr.attr.attr,
#define PCR_ATTR_GROUP_ARRAY(_alg, _hash) \
static struct attribute *pcr_group_attrs_##_hash[] = { \
_TPM_HELPER(_alg, _hash, PCR_ATTR_VAL) \
NULL \
}
#define PCR_ATTR_GROUP(_alg, _hash) \
static struct attribute_group pcr_group_##_hash = { \
.name = "pcr-" __stringify(_hash), \
.attrs = pcr_group_attrs_##_hash \
}
#define PCR_ATTR_BUILD(_alg, _hash) \
PCR_ATTRS(_alg, _hash) \
PCR_ATTR_GROUP_ARRAY(_alg, _hash); \
PCR_ATTR_GROUP(_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(TPM_ALG_SHA1, sha1);
PCR_ATTR_BUILD(TPM_ALG_SHA256, sha256);
PCR_ATTR_BUILD(TPM_ALG_SHA384, sha384);
PCR_ATTR_BUILD(TPM_ALG_SHA512, sha512);
PCR_ATTR_BUILD(TPM_ALG_SM3_256, sm3);
void tpm_sysfs_add_device(struct tpm_chip *chip)
{
int i;
WARN_ON(chip->groups_cnt != 0);
if (tpm_is_firmware_upgrade(chip))
return;
if (chip->flags & TPM_CHIP_FLAG_TPM2)
chip->groups[chip->groups_cnt++] = &tpm2_dev_group;
else
chip->groups[chip->groups_cnt++] = &tpm1_dev_group;
/* add one group for each bank hash */
for (i = 0; i < chip->nr_allocated_banks; i++) {
switch (chip->allocated_banks[i].alg_id) {
case TPM_ALG_SHA1:
chip->groups[chip->groups_cnt++] = &pcr_group_sha1;
break;
case TPM_ALG_SHA256:
chip->groups[chip->groups_cnt++] = &pcr_group_sha256;
break;
case TPM_ALG_SHA384:
chip->groups[chip->groups_cnt++] = &pcr_group_sha384;
break;
case TPM_ALG_SHA512:
chip->groups[chip->groups_cnt++] = &pcr_group_sha512;
break;
case TPM_ALG_SM3_256:
chip->groups[chip->groups_cnt++] = &pcr_group_sm3;
break;
default:
/*
* If triggers, send a patch to add both a
* PCR_ATTR_BUILD() macro above for the
* missing algorithm as well as an additional
* case in this switch statement.
*/
dev_err(&chip->dev,
"TPM with unsupported bank algorithm 0x%04x",
chip->allocated_banks[i].alg_id);
break;
}
}
/*
* This will only trigger if someone has added an additional
* hash to the tpm_algorithms enum without incrementing
* TPM_MAX_HASHES.
*/
WARN_ON(chip->groups_cnt > TPM_MAX_HASHES + 1);
}