- 根目录:
- drivers
- char
- tpm
- tpm.c
/*
* 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>
*
* Maintained by: <tpmdd-devel@lists.sourceforge.net>
*
* 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 <linux/poll.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include "tpm.h"
enum tpm_const {
TPM_MINOR = 224, /* officially assigned */
TPM_BUFSIZE = 4096,
TPM_NUM_DEVICES = 256,
};
enum tpm_duration {
TPM_SHORT = 0,
TPM_MEDIUM = 1,
TPM_LONG = 2,
TPM_UNDEFINED,
};
#define TPM_MAX_ORDINAL 243
#define TPM_MAX_PROTECTED_ORDINAL 12
#define TPM_PROTECTED_ORDINAL_MASK 0xFF
/*
* 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 faciltate flush on suspend.");
static LIST_HEAD(tpm_chip_list);
static DEFINE_SPINLOCK(driver_lock);
static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
/*
* 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_protected_ordinal_duration[TPM_MAX_PROTECTED_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,
};
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,
};
static void user_reader_timeout(unsigned long ptr)
{
struct tpm_chip *chip = (struct tpm_chip *) ptr;
schedule_work(&chip->work);
}
static void timeout_work(struct work_struct *work)
{
struct tpm_chip *chip = container_of(work, struct tpm_chip, work);
mutex_lock(&chip->buffer_mutex);
atomic_set(&chip->data_pending, 0);
memset(chip->data_buffer, 0, TPM_BUFSIZE);
mutex_unlock(&chip->buffer_mutex);
}
/*
* 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;
if (ordinal < TPM_MAX_ORDINAL)
duration_idx = tpm_ordinal_duration[ordinal];
else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
TPM_MAX_PROTECTED_ORDINAL)
duration_idx =
tpm_protected_ordinal_duration[ordinal &
TPM_PROTECTED_ORDINAL_MASK];
if (duration_idx != TPM_UNDEFINED)
duration = chip->vendor.duration[duration_idx];
if (duration <= 0)
return 2 * 60 * HZ;
else
return duration;
}
EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
/*
* Internal kernel interface to transmit TPM commands
*/
static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
size_t bufsiz)
{
ssize_t rc;
u32 count, ordinal;
unsigned long stop;
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;
}
mutex_lock(&chip->tpm_mutex);
if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
dev_err(chip->dev,
"tpm_transmit: tpm_send: error %zd\n", rc);
goto out;
}
if (chip->vendor.irq)
goto out_recv;
stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
do {
u8 status = chip->vendor.status(chip);
if ((status & chip->vendor.req_complete_mask) ==
chip->vendor.req_complete_val)
goto out_recv;
if ((status == chip->vendor.req_canceled)) {
dev_err(chip->dev, "Operation Canceled\n");
rc = -ECANCELED;
goto out;
}
msleep(TPM_TIMEOUT); /* CHECK */
rmb();
} while (time_before(jiffies, stop));
chip->vendor.cancel(chip);
dev_err(chip->dev, "Operation Timed out\n");
rc = -ETIME;
goto out;
out_recv:
rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
if (rc < 0)
dev_err(chip->dev,
"tpm_transmit: tpm_recv: error %zd\n", rc);
out:
mutex_unlock(&chip->tpm_mutex);
return rc;
}
#define TPM_DIGEST_SIZE 20
#define TPM_ERROR_SIZE 10
#define TPM_RET_CODE_IDX 6
enum tpm_capabilities {
TPM_CAP_FLAG = cpu_to_be32(4),
TPM_CAP_PROP = cpu_to_be32(5),
CAP_VERSION_1_1 = cpu_to_be32(0x06),
CAP_VERSION_1_2 = cpu_to_be32(0x1A)
};
enum tpm_sub_capabilities {
TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
};
static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
int len, const char *desc)
{
int err;
len = tpm_transmit(chip,(u8 *) cmd, len);
if (len < 0)
return len;
if (len == TPM_ERROR_SIZE) {
err = be32_to_cpu(cmd->header.out.return_code);
dev_dbg(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
return err;
}
return 0;
}
#define TPM_INTERNAL_RESULT_SIZE 200
#define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
#define TPM_ORD_GET_CAP cpu_to_be32(101)
static const struct tpm_input_header tpm_getcap_header = {
.tag = TPM_TAG_RQU_COMMAND,
.length = cpu_to_be32(22),
.ordinal = TPM_ORD_GET_CAP
};
ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
const char *desc)
{
struct tpm_cmd_t tpm_cmd;
int rc;
struct tpm_chip *chip = dev_get_drvdata(dev);
tpm_cmd.header.in = tpm_getcap_header;
if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
tpm_cmd.params.getcap_in.cap = subcap_id;
/*subcap field not necessary */
tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
} else {
if (subcap_id == TPM_CAP_FLAG_PERM ||
subcap_id == TPM_CAP_FLAG_VOL)
tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
else
tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
tpm_cmd.params.getcap_in.subcap = subcap_id;
}
rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
if (!rc)
*cap = tpm_cmd.params.getcap_out.cap;
return rc;
}
void tpm_gen_interrupt(struct tpm_chip *chip)
{
struct tpm_cmd_t tpm_cmd;
ssize_t rc;
tpm_cmd.header.in = tpm_getcap_header;
tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
"attempting to determine the timeouts");
}
EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
void tpm_get_timeouts(struct tpm_chip *chip)
{
struct tpm_cmd_t tpm_cmd;
struct timeout_t *timeout_cap;
struct duration_t *duration_cap;
ssize_t rc;
u32 timeout;
tpm_cmd.header.in = tpm_getcap_header;
tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
"attempting to determine the timeouts");
if (rc)
goto duration;
if (be32_to_cpu(tpm_cmd.header.out.length)
!= 4 * sizeof(u32))
goto duration;
timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
/* Don't overwrite default if value is 0 */
timeout = be32_to_cpu(timeout_cap->a);
if (timeout)
chip->vendor.timeout_a = usecs_to_jiffies(timeout);
timeout = be32_to_cpu(timeout_cap->b);
if (timeout)
chip->vendor.timeout_b = usecs_to_jiffies(timeout);
timeout = be32_to_cpu(timeout_cap->c);
if (timeout)
chip->vendor.timeout_c = usecs_to_jiffies(timeout);
timeout = be32_to_cpu(timeout_cap->d);
if (timeout)
chip->vendor.timeout_d = usecs_to_jiffies(timeout);
duration:
tpm_cmd.header.in = tpm_getcap_header;
tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
"attempting to determine the durations");
if (rc)
return;
if (be32_to_cpu(tpm_cmd.header.out.return_code)
!= 3 * sizeof(u32))
return;
duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
chip->vendor.duration[TPM_SHORT] =
usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
/* 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.
*/
if (chip->vendor.duration[TPM_SHORT] < (HZ/100))
chip->vendor.duration[TPM_SHORT] = HZ;
chip->vendor.duration[TPM_MEDIUM] =
usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
chip->vendor.duration[TPM_LONG] =
usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
}
EXPORT_SYMBOL_GPL(tpm_get_timeouts);
void tpm_continue_selftest(struct tpm_chip *chip)
{
u8 data[] = {
0, 193, /* TPM_TAG_RQU_COMMAND */
0, 0, 0, 10, /* length */
0, 0, 0, 83, /* TPM_ORD_GetCapability */
};
tpm_transmit(chip, data, sizeof(data));
}
EXPORT_SYMBOL_GPL(tpm_continue_selftest);
ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
char *buf)
{
cap_t cap;
ssize_t rc;
rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
"attempting to determine the permanent enabled state");
if (rc)
return 0;
rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
return rc;
}
EXPORT_SYMBOL_GPL(tpm_show_enabled);
ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
char *buf)
{
cap_t cap;
ssize_t rc;
rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
"attempting to determine the permanent active state");
if (rc)
return 0;
rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
return rc;
}
EXPORT_SYMBOL_GPL(tpm_show_active);
ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
char *buf)
{
cap_t cap;
ssize_t rc;
rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
"attempting to determine the owner state");
if (rc)
return 0;
rc = sprintf(buf, "%d\n", cap.owned);
return rc;
}
EXPORT_SYMBOL_GPL(tpm_show_owned);
ssize_t tpm_show_temp_deactivated(struct device * dev,
struct device_attribute * attr, char *buf)
{
cap_t cap;
ssize_t rc;
rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
"attempting to determine the temporary state");
if (rc)
return 0;
rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
return rc;
}
EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
/*
* tpm_chip_find_get - return tpm_chip for given chip number
*/
static struct tpm_chip *tpm_chip_find_get(int chip_num)
{
struct tpm_chip *pos, *chip = NULL;
rcu_read_lock();
list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
continue;
if (try_module_get(pos->dev->driver->owner)) {
chip = pos;
break;
}
}
rcu_read_unlock();
return chip;
}
#define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
#define READ_PCR_RESULT_SIZE 30
static struct tpm_input_header pcrread_header = {
.tag = TPM_TAG_RQU_COMMAND,
.length = cpu_to_be32(14),
.ordinal = TPM_ORDINAL_PCRREAD
};
int __tpm_pcr_read(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 = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
"attempting to read a pcr value");
if (rc == 0)
memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
TPM_DIGEST_SIZE);
return rc;
}
/**
* tpm_pcr_read - read a pcr value
* @chip_num: tpm idx # or ANY
* @pcr_idx: pcr idx to retrieve
* @res_buf: TPM_PCR value
* size of res_buf is 20 bytes (or NULL if you don't care)
*
* The TPM driver should be built-in, but for whatever reason it
* isn't, protect against the chip disappearing, by incrementing
* the module usage count.
*/
int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
{
struct tpm_chip *chip;
int rc;
chip = tpm_chip_find_get(chip_num);
if (chip == NULL)
return -ENODEV;
rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
tpm_chip_put(chip);
return rc;
}
EXPORT_SYMBOL_GPL(tpm_pcr_read);
/**
* tpm_pcr_extend - extend pcr value with hash
* @chip_num: tpm idx # or AN&
* @pcr_idx: pcr idx to extend
* @hash: hash value used to extend pcr value
*
* The TPM driver should be built-in, but for whatever reason it
* isn't, protect against the chip disappearing, by incrementing
* the module usage count.
*/
#define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
#define EXTEND_PCR_RESULT_SIZE 34
static struct tpm_input_header pcrextend_header = {
.tag = TPM_TAG_RQU_COMMAND,
.length = cpu_to_be32(34),
.ordinal = TPM_ORD_PCR_EXTEND
};
int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
{
struct tpm_cmd_t cmd;
int rc;
struct tpm_chip *chip;
chip = tpm_chip_find_get(chip_num);
if (chip == NULL)
return -ENODEV;
cmd.header.in = pcrextend_header;
cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
"attempting extend a PCR value");
tpm_chip_put(chip);
return rc;
}
EXPORT_SYMBOL_GPL(tpm_pcr_extend);
int tpm_send(u32 chip_num, void *cmd, size_t buflen)
{
struct tpm_chip *chip;
int rc;
chip = tpm_chip_find_get(chip_num);
if (chip == NULL)
return -ENODEV;
rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
tpm_chip_put(chip);
return rc;
}
EXPORT_SYMBOL_GPL(tpm_send);
ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
char *buf)
{
cap_t cap;
u8 digest[TPM_DIGEST_SIZE];
ssize_t rc;
int i, j, num_pcrs;
char *str = buf;
struct tpm_chip *chip = dev_get_drvdata(dev);
rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
"attempting to determine the number of PCRS");
if (rc)
return 0;
num_pcrs = be32_to_cpu(cap.num_pcrs);
for (i = 0; i < num_pcrs; i++) {
rc = __tpm_pcr_read(chip, i, digest);
if (rc)
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");
}
return str - buf;
}
EXPORT_SYMBOL_GPL(tpm_show_pcrs);
#define READ_PUBEK_RESULT_SIZE 314
#define TPM_ORD_READPUBEK cpu_to_be32(124)
struct tpm_input_header tpm_readpubek_header = {
.tag = TPM_TAG_RQU_COMMAND,
.length = cpu_to_be32(30),
.ordinal = TPM_ORD_READPUBEK
};
ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
char *buf)
{
u8 *data;
struct tpm_cmd_t tpm_cmd;
ssize_t err;
int i, rc;
char *str = buf;
struct tpm_chip *chip = dev_get_drvdata(dev);
tpm_cmd.header.in = tpm_readpubek_header;
err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
"attempting to read the PUBEK");
if (err)
goto out;
/*
ignore header 10 bytes
algorithm 32 bits (1 == RSA )
encscheme 16 bits
sigscheme 16 bits
parameters (RSA 12->bytes: keybit, #primes, expbit)
keylenbytes 32 bits
256 byte modulus
ignore checksum 20 bytes
*/
data = tpm_cmd.params.readpubek_out_buffer;
str +=
sprintf(str,
"Algorithm: %02X %02X %02X %02X\nEncscheme: %02X %02X\n"
"Sigscheme: %02X %02X\nParameters: %02X %02X %02X %02X"
" %02X %02X %02X %02X %02X %02X %02X %02X\n"
"Modulus length: %d\nModulus: \n",
data[10], data[11], data[12], data[13], data[14],
data[15], data[16], data[17], data[22], data[23],
data[24], data[25], data[26], data[27], data[28],
data[29], data[30], data[31], data[32], data[33],
be32_to_cpu(*((__be32 *) (data + 34))));
for (i = 0; i < 256; i++) {
str += sprintf(str, "%02X ", data[i + 38]);
if ((i + 1) % 16 == 0)
str += sprintf(str, "\n");
}
out:
rc = str - buf;
return rc;
}
EXPORT_SYMBOL_GPL(tpm_show_pubek);
ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
char *buf)
{
cap_t cap;
ssize_t rc;
char *str = buf;
rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
"attempting to determine the manufacturer");
if (rc)
return 0;
str += sprintf(str, "Manufacturer: 0x%x\n",
be32_to_cpu(cap.manufacturer_id));
rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
"attempting to determine the 1.1 version");
if (rc)
return 0;
str += sprintf(str,
"TCG version: %d.%d\nFirmware version: %d.%d\n",
cap.tpm_version.Major, cap.tpm_version.Minor,
cap.tpm_version.revMajor, cap.tpm_version.revMinor);
return str - buf;
}
EXPORT_SYMBOL_GPL(tpm_show_caps);
ssize_t tpm_show_caps_1_2(struct device * dev,
struct device_attribute * attr, char *buf)
{
cap_t cap;
ssize_t rc;
char *str = buf;
rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
"attempting to determine the manufacturer");
if (rc)
return 0;
str += sprintf(str, "Manufacturer: 0x%x\n",
be32_to_cpu(cap.manufacturer_id));
rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
"attempting to determine the 1.2 version");
if (rc)
return 0;
str += sprintf(str,
"TCG version: %d.%d\nFirmware version: %d.%d\n",
cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
cap.tpm_version_1_2.revMajor,
cap.tpm_version_1_2.revMinor);
return str - buf;
}
EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct tpm_chip *chip = dev_get_drvdata(dev);
if (chip == NULL)
return 0;
chip->vendor.cancel(chip);
return count;
}
EXPORT_SYMBOL_GPL(tpm_store_cancel);
/*
* Device file system interface to the TPM
*
* It's assured that the chip will be opened just once,
* by the check of is_open variable, which is protected
* by driver_lock.
*/
int tpm_open(struct inode *inode, struct file *file)
{
int minor = iminor(inode);
struct tpm_chip *chip = NULL, *pos;
rcu_read_lock();
list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
if (pos->vendor.miscdev.minor == minor) {
chip = pos;
get_device(chip->dev);
break;
}
}
rcu_read_unlock();
if (!chip)
return -ENODEV;
if (test_and_set_bit(0, &chip->is_open)) {
dev_dbg(chip->dev, "Another process owns this TPM\n");
put_device(chip->dev);
return -EBUSY;
}
chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
if (chip->data_buffer == NULL) {
clear_bit(0, &chip->is_open);
put_device(chip->dev);
return -ENOMEM;
}
atomic_set(&chip->data_pending, 0);
file->private_data = chip;
return 0;
}
EXPORT_SYMBOL_GPL(tpm_open);
/*
* Called on file close
*/
int tpm_release(struct inode *inode, struct file *file)
{
struct tpm_chip *chip = file->private_data;
del_singleshot_timer_sync(&chip->user_read_timer);
flush_work_sync(&chip->work);
file->private_data = NULL;
atomic_set(&chip->data_pending, 0);
kfree(chip->data_buffer);
clear_bit(0, &chip->is_open);
put_device(chip->dev);
return 0;
}
EXPORT_SYMBOL_GPL(tpm_release);
ssize_t tpm_write(struct file *file, const char __user *buf,
size_t size, loff_t *off)
{
struct tpm_chip *chip = file->private_data;
size_t in_size = size;
ssize_t out_size;
/* cannot perform a write until the read has cleared
either via tpm_read or a user_read_timer timeout.
This also prevents splitted buffered writes from blocking here.
*/
if (atomic_read(&chip->data_pending) != 0)
return -EBUSY;
if (in_size > TPM_BUFSIZE)
return -E2BIG;
mutex_lock(&chip->buffer_mutex);
if (copy_from_user
(chip->data_buffer, (void __user *) buf, in_size)) {
mutex_unlock(&chip->buffer_mutex);
return -EFAULT;
}
/* atomic tpm command send and result receive */
out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
if (out_size < 0) {
mutex_unlock(&chip->buffer_mutex);
return out_size;
}
atomic_set(&chip->data_pending, out_size);
mutex_unlock(&chip->buffer_mutex);
/* Set a timeout by which the reader must come claim the result */
mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
return in_size;
}
EXPORT_SYMBOL_GPL(tpm_write);
ssize_t tpm_read(struct file *file, char __user *buf,
size_t size, loff_t *off)
{
struct tpm_chip *chip = file->private_data;
ssize_t ret_size;
int rc;
del_singleshot_timer_sync(&chip->user_read_timer);
flush_work_sync(&chip->work);
ret_size = atomic_read(&chip->data_pending);
atomic_set(&chip->data_pending, 0);
if (ret_size > 0) { /* relay data */
if (size < ret_size)
ret_size = size;
mutex_lock(&chip->buffer_mutex);
rc = copy_to_user(buf, chip->data_buffer, ret_size);
memset(chip->data_buffer, 0, ret_size);
if (rc)
ret_size = -EFAULT;
mutex_unlock(&chip->buffer_mutex);
}
return ret_size;
}
EXPORT_SYMBOL_GPL(tpm_read);
void tpm_remove_hardware(struct device *dev)
{
struct tpm_chip *chip = dev_get_drvdata(dev);
if (chip == NULL) {
dev_err(dev, "No device data found\n");
return;
}
spin_lock(&driver_lock);
list_del_rcu(&chip->list);
spin_unlock(&driver_lock);
synchronize_rcu();
misc_deregister(&chip->vendor.miscdev);
sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
tpm_bios_log_teardown(chip->bios_dir);
/* write it this way to be explicit (chip->dev == dev) */
put_device(chip->dev);
}
EXPORT_SYMBOL_GPL(tpm_remove_hardware);
#define TPM_ORD_SAVESTATE cpu_to_be32(152)
#define SAVESTATE_RESULT_SIZE 10
static struct tpm_input_header savestate_header = {
.tag = TPM_TAG_RQU_COMMAND,
.length = cpu_to_be32(10),
.ordinal = 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, pm_message_t pm_state)
{
struct tpm_chip *chip = dev_get_drvdata(dev);
struct tpm_cmd_t cmd;
int rc;
u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
if (chip == NULL)
return -ENODEV;
/* for buggy tpm, flush pcrs with extend to selected dummy */
if (tpm_suspend_pcr) {
cmd.header.in = pcrextend_header;
cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
TPM_DIGEST_SIZE);
rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
"extending dummy pcr before suspend");
}
/* now do the actual savestate */
cmd.header.in = savestate_header;
rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE,
"sending savestate before suspend");
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);
/* In case vendor provided release function, call it too.*/
void tpm_dev_vendor_release(struct tpm_chip *chip)
{
if (chip->vendor.release)
chip->vendor.release(chip->dev);
clear_bit(chip->dev_num, dev_mask);
kfree(chip->vendor.miscdev.name);
}
EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
/*
* Once all references to platform device are down to 0,
* release all allocated structures.
*/
void tpm_dev_release(struct device *dev)
{
struct tpm_chip *chip = dev_get_drvdata(dev);
tpm_dev_vendor_release(chip);
chip->release(dev);
kfree(chip);
}
EXPORT_SYMBOL_GPL(tpm_dev_release);
/*
* Called from tpm_<specific>.c probe function only for devices
* the driver has determined it should claim. Prior to calling
* this function the specific probe function has called pci_enable_device
* upon errant exit from this function specific probe function should call
* pci_disable_device
*/
struct tpm_chip *tpm_register_hardware(struct device *dev,
const struct tpm_vendor_specific *entry)
{
#define DEVNAME_SIZE 7
char *devname;
struct tpm_chip *chip;
/* Driver specific per-device data */
chip = kzalloc(sizeof(*chip), GFP_KERNEL);
devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
if (chip == NULL || devname == NULL)
goto out_free;
mutex_init(&chip->buffer_mutex);
mutex_init(&chip->tpm_mutex);
INIT_LIST_HEAD(&chip->list);
INIT_WORK(&chip->work, timeout_work);
setup_timer(&chip->user_read_timer, user_reader_timeout,
(unsigned long)chip);
memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
if (chip->dev_num >= TPM_NUM_DEVICES) {
dev_err(dev, "No available tpm device numbers\n");
goto out_free;
} else if (chip->dev_num == 0)
chip->vendor.miscdev.minor = TPM_MINOR;
else
chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
set_bit(chip->dev_num, dev_mask);
scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
chip->vendor.miscdev.name = devname;
chip->vendor.miscdev.parent = dev;
chip->dev = get_device(dev);
chip->release = dev->release;
dev->release = tpm_dev_release;
dev_set_drvdata(dev, chip);
if (misc_register(&chip->vendor.miscdev)) {
dev_err(chip->dev,
"unable to misc_register %s, minor %d\n",
chip->vendor.miscdev.name,
chip->vendor.miscdev.minor);
put_device(chip->dev);
return NULL;
}
if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
misc_deregister(&chip->vendor.miscdev);
put_device(chip->dev);
return NULL;
}
chip->bios_dir = tpm_bios_log_setup(devname);
/* Make chip available */
spin_lock(&driver_lock);
list_add_rcu(&chip->list, &tpm_chip_list);
spin_unlock(&driver_lock);
return chip;
out_free:
kfree(chip);
kfree(devname);
return NULL;
}
EXPORT_SYMBOL_GPL(tpm_register_hardware);
MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
MODULE_DESCRIPTION("TPM Driver");
MODULE_VERSION("2.0");
MODULE_LICENSE("GPL");