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6b07d30aca
linux/drivers/char/tpm/tpm.c
Peter Huewe 6b07d30aca TPM: Call tpm_transmit with correct size 
This patch changes the call of tpm_transmit by supplying the size of the
userspace buffer instead of TPM_BUFSIZE.

This got assigned CVE-2011-1161.

[The first hunk didn't make sense given one could expect
 way less data than TPM_BUFSIZE, so added tpm_transmit boundary
 check over bufsiz instead
 The last parameter of tpm_transmit() reflects the amount
 of data expected from the device, and not the buffer size
 being supplied to it. It isn't ideal to parse it directly,
 so we just set it to the maximum the input buffer can handle
 and let the userspace API to do such job.]

Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Cc: Stable Kernel <stable@kernel.org>
Signed-off-by: James Morris <jmorris@namei.org>
2011-09-23 09:46:29 +10:00

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/*
* 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;
unsigned int scale = 1;
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.return_code) != 0 ||
be32_to_cpu(tpm_cmd.header.out.length)
!= sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
return;
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 && timeout < 1000) {
/* timeouts in msec rather usec */
scale = 1000;
chip->vendor.timeout_adjusted = true;
}
if (timeout)
chip->vendor.timeout_a = usecs_to_jiffies(timeout * scale);
timeout = be32_to_cpu(timeout_cap->b);
if (timeout)
chip->vendor.timeout_b = usecs_to_jiffies(timeout * scale);
timeout = be32_to_cpu(timeout_cap->c);
if (timeout)
chip->vendor.timeout_c = usecs_to_jiffies(timeout * scale);
timeout = be32_to_cpu(timeout_cap->d);
if (timeout)
chip->vendor.timeout_d = usecs_to_jiffies(timeout * scale);
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) != 0 ||
be32_to_cpu(tpm_cmd.header.out.length)
!= sizeof(tpm_cmd.header.out) + sizeof(u32) + 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));
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));
/* 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->vendor.duration[TPM_SHORT] < (HZ / 100)) {
chip->vendor.duration[TPM_SHORT] = HZ;
chip->vendor.duration[TPM_MEDIUM] *= 1000;
chip->vendor.duration[TPM_LONG] *= 1000;
chip->vendor.duration_adjusted = true;
dev_info(chip->dev, "Adjusting TPM timeout parameters.");
}
}
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_ContinueSelfTest */
};
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\n"
"Encscheme: %02X %02X\n"
"Sigscheme: %02X %02X\n"
"Parameters: %02X %02X %02X %02X "
"%02X %02X %02X %02X "
"%02X %02X %02X %02X\n"
"Modulus length: %d\n"
"Modulus:\n",
data[0], data[1], data[2], data[3],
data[4], data[5],
data[6], data[7],
data[12], data[13], data[14], data[15],
data[16], data[17], data[18], data[19],
data[20], data[21], data[22], data[23],
be32_to_cpu(*((__be32 *) (data + 24))));
for (i = 0; i < 256; i++) {
str += sprintf(str, "%02X ", data[i + 28]);
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_show_durations(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct tpm_chip *chip = dev_get_drvdata(dev);
return sprintf(buf, "%d %d %d [%s]\n",
jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
jiffies_to_usecs(chip->vendor.duration[TPM_LONG]),
chip->vendor.duration_adjusted
? "adjusted" : "original");
}
EXPORT_SYMBOL_GPL(tpm_show_durations);
ssize_t tpm_show_timeouts(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct tpm_chip *chip = dev_get_drvdata(dev);
return sprintf(buf, "%d %d %d %d [%s]\n",
jiffies_to_usecs(chip->vendor.timeout_a),
jiffies_to_usecs(chip->vendor.timeout_b),
jiffies_to_usecs(chip->vendor.timeout_c),
jiffies_to_usecs(chip->vendor.timeout_d),
chip->vendor.timeout_adjusted
? "adjusted" : "original");
}
EXPORT_SYMBOL_GPL(tpm_show_timeouts);
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, out_size;
/* cannot perform a write until the read has cleared
either via tpm_read or a user_read_timer timeout */
while (atomic_read(&chip->data_pending) != 0)
msleep(TPM_TIMEOUT);
mutex_lock(&chip->buffer_mutex);
if (in_size > TPM_BUFSIZE)
in_size = TPM_BUFSIZE;
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);
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;
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);
if (copy_to_user(buf, chip->data_buffer, ret_size))
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");
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