linux/drivers/char/tpm/tpm.h

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/*
* Copyright (C) 2004 IBM Corporation
* Copyright (C) 2015 Intel 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.
*
*/
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/fs.h>
#include <linux/mutex.h>
#include <linux/sched.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/tpm.h>
#include <linux/acpi.h>
#include <linux/cdev.h>
#include <linux/highmem.h>
enum tpm_const {
TPM_MINOR = 224, /* officially assigned */
TPM_BUFSIZE = 4096,
TPM_NUM_DEVICES = 65536,
TPM: Retry SaveState command in suspend path If the TPM has already been sent a SaveState command before the driver is loaded it may have problems sending that same command again later. This issue is seen with the Chromebook Pixel due to a firmware bug in the legacy mode boot path which is sending the SaveState command before booting the kernel. More information is available at http://crbug.com/203524 This change introduces a retry of the SaveState command in the suspend path in order to work around this issue. A future firmware update should fix this but this is also a trivial workaround in the driver that has no effect on systems that do not show this problem. When this does happen the TPM responds with a non-fatal TPM_RETRY code that is defined in the specification: The TPM is too busy to respond to the command immediately, but the command could be resubmitted at a later time. The TPM MAY return TPM_RETRY for any command at any time. It can take several seconds before the TPM will respond again. I measured a typical time between 3 and 4 seconds and the timeout is set at a safe 5 seconds. It is also possible to reproduce this with commands via /dev/tpm0. The bug linked above has a python script attached which can be used to test for this problem. I tested a variety of TPMs from Infineon, Nuvoton, Atmel, and STMicro but was only able to reproduce this with LPC and I2C TPMs from Infineon. The TPM specification only loosely defines this behavior: TPM Main Level 2 Part 3 v1.2 r116, section 3.3. TPM_SaveState: The TPM MAY declare all preserved values invalid in response to any command other than TPM_Init. TCG PC Client BIOS Spec 1.21 section 8.3.1. After issuing a TPM_SaveState command, the OS SHOULD NOT issue TPM commands before transitioning to S3 without issuing another TPM_SaveState command. TCG PC Client TIS 1.21, section 4. Power Management: The TPM_SaveState command allows a Static OS to indicate to the TPM that the platform may enter a low power state where the TPM will be required to enter into the D3 power state. The use of the term "may" is significant in that there is no requirement for the platform to actually enter the low power state after sending the TPM_SaveState command. The software may, in fact, send subsequent commands after sending the TPM_SaveState command. Change-Id: I52b41e826412688e5b6c8ddd3bb16409939704e9 Signed-off-by: Duncan Laurie <dlaurie@chromium.org> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2013-03-17 21:56:39 +00:00
TPM_RETRY = 50, /* 5 seconds */
};
enum tpm_timeout {
TPM_TIMEOUT = 5, /* msecs */
TPM: Retry SaveState command in suspend path If the TPM has already been sent a SaveState command before the driver is loaded it may have problems sending that same command again later. This issue is seen with the Chromebook Pixel due to a firmware bug in the legacy mode boot path which is sending the SaveState command before booting the kernel. More information is available at http://crbug.com/203524 This change introduces a retry of the SaveState command in the suspend path in order to work around this issue. A future firmware update should fix this but this is also a trivial workaround in the driver that has no effect on systems that do not show this problem. When this does happen the TPM responds with a non-fatal TPM_RETRY code that is defined in the specification: The TPM is too busy to respond to the command immediately, but the command could be resubmitted at a later time. The TPM MAY return TPM_RETRY for any command at any time. It can take several seconds before the TPM will respond again. I measured a typical time between 3 and 4 seconds and the timeout is set at a safe 5 seconds. It is also possible to reproduce this with commands via /dev/tpm0. The bug linked above has a python script attached which can be used to test for this problem. I tested a variety of TPMs from Infineon, Nuvoton, Atmel, and STMicro but was only able to reproduce this with LPC and I2C TPMs from Infineon. The TPM specification only loosely defines this behavior: TPM Main Level 2 Part 3 v1.2 r116, section 3.3. TPM_SaveState: The TPM MAY declare all preserved values invalid in response to any command other than TPM_Init. TCG PC Client BIOS Spec 1.21 section 8.3.1. After issuing a TPM_SaveState command, the OS SHOULD NOT issue TPM commands before transitioning to S3 without issuing another TPM_SaveState command. TCG PC Client TIS 1.21, section 4. Power Management: The TPM_SaveState command allows a Static OS to indicate to the TPM that the platform may enter a low power state where the TPM will be required to enter into the D3 power state. The use of the term "may" is significant in that there is no requirement for the platform to actually enter the low power state after sending the TPM_SaveState command. The software may, in fact, send subsequent commands after sending the TPM_SaveState command. Change-Id: I52b41e826412688e5b6c8ddd3bb16409939704e9 Signed-off-by: Duncan Laurie <dlaurie@chromium.org> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2013-03-17 21:56:39 +00:00
TPM_TIMEOUT_RETRY = 100 /* msecs */
};
/* TPM addresses */
enum tpm_addr {
TPM_SUPERIO_ADDR = 0x2E,
TPM_ADDR = 0x4E,
};
/* Indexes the duration array */
enum tpm_duration {
TPM_SHORT = 0,
TPM_MEDIUM = 1,
TPM_LONG = 2,
TPM_UNDEFINED,
};
TPM: Retry SaveState command in suspend path If the TPM has already been sent a SaveState command before the driver is loaded it may have problems sending that same command again later. This issue is seen with the Chromebook Pixel due to a firmware bug in the legacy mode boot path which is sending the SaveState command before booting the kernel. More information is available at http://crbug.com/203524 This change introduces a retry of the SaveState command in the suspend path in order to work around this issue. A future firmware update should fix this but this is also a trivial workaround in the driver that has no effect on systems that do not show this problem. When this does happen the TPM responds with a non-fatal TPM_RETRY code that is defined in the specification: The TPM is too busy to respond to the command immediately, but the command could be resubmitted at a later time. The TPM MAY return TPM_RETRY for any command at any time. It can take several seconds before the TPM will respond again. I measured a typical time between 3 and 4 seconds and the timeout is set at a safe 5 seconds. It is also possible to reproduce this with commands via /dev/tpm0. The bug linked above has a python script attached which can be used to test for this problem. I tested a variety of TPMs from Infineon, Nuvoton, Atmel, and STMicro but was only able to reproduce this with LPC and I2C TPMs from Infineon. The TPM specification only loosely defines this behavior: TPM Main Level 2 Part 3 v1.2 r116, section 3.3. TPM_SaveState: The TPM MAY declare all preserved values invalid in response to any command other than TPM_Init. TCG PC Client BIOS Spec 1.21 section 8.3.1. After issuing a TPM_SaveState command, the OS SHOULD NOT issue TPM commands before transitioning to S3 without issuing another TPM_SaveState command. TCG PC Client TIS 1.21, section 4. Power Management: The TPM_SaveState command allows a Static OS to indicate to the TPM that the platform may enter a low power state where the TPM will be required to enter into the D3 power state. The use of the term "may" is significant in that there is no requirement for the platform to actually enter the low power state after sending the TPM_SaveState command. The software may, in fact, send subsequent commands after sending the TPM_SaveState command. Change-Id: I52b41e826412688e5b6c8ddd3bb16409939704e9 Signed-off-by: Duncan Laurie <dlaurie@chromium.org> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
2013-03-17 21:56:39 +00:00
#define TPM_WARN_RETRY 0x800
#define TPM_WARN_DOING_SELFTEST 0x802
#define TPM_ERR_DEACTIVATED 0x6
#define TPM_ERR_DISABLED 0x7
#define TPM_ERR_INVALID_POSTINIT 38
#define TPM_HEADER_SIZE 10
enum tpm2_const {
TPM2_PLATFORM_PCR = 24,
TPM2_PCR_SELECT_MIN = ((TPM2_PLATFORM_PCR + 7) / 8),
TPM2_TIMEOUT_A = 750,
TPM2_TIMEOUT_B = 2000,
TPM2_TIMEOUT_C = 200,
TPM2_TIMEOUT_D = 30,
TPM2_DURATION_SHORT = 20,
TPM2_DURATION_MEDIUM = 750,
TPM2_DURATION_LONG = 2000,
};
enum tpm2_structures {
TPM2_ST_NO_SESSIONS = 0x8001,
TPM2_ST_SESSIONS = 0x8002,
};
enum tpm2_return_codes {
TPM2_RC_HASH = 0x0083, /* RC_FMT1 */
TPM2_RC_INITIALIZE = 0x0100, /* RC_VER1 */
TPM2_RC_DISABLED = 0x0120,
TPM2_RC_TESTING = 0x090A, /* RC_WARN */
};
enum tpm2_algorithms {
TPM2_ALG_SHA1 = 0x0004,
TPM2_ALG_KEYEDHASH = 0x0008,
TPM2_ALG_SHA256 = 0x000B,
TPM2_ALG_SHA384 = 0x000C,
TPM2_ALG_SHA512 = 0x000D,
TPM2_ALG_NULL = 0x0010,
TPM2_ALG_SM3_256 = 0x0012,
};
enum tpm2_command_codes {
TPM2_CC_FIRST = 0x011F,
TPM2_CC_SELF_TEST = 0x0143,
TPM2_CC_STARTUP = 0x0144,
TPM2_CC_SHUTDOWN = 0x0145,
TPM2_CC_CREATE = 0x0153,
TPM2_CC_LOAD = 0x0157,
TPM2_CC_UNSEAL = 0x015E,
TPM2_CC_FLUSH_CONTEXT = 0x0165,
TPM2_CC_GET_CAPABILITY = 0x017A,
TPM2_CC_GET_RANDOM = 0x017B,
TPM2_CC_PCR_READ = 0x017E,
TPM2_CC_PCR_EXTEND = 0x0182,
TPM2_CC_LAST = 0x018F,
};
enum tpm2_permanent_handles {
TPM2_RS_PW = 0x40000009,
};
enum tpm2_capabilities {
TPM2_CAP_TPM_PROPERTIES = 6,
};
enum tpm2_startup_types {
TPM2_SU_CLEAR = 0x0000,
TPM2_SU_STATE = 0x0001,
};
#define TPM_VID_INTEL 0x8086
#define TPM_VID_WINBOND 0x1050
#define TPM_VID_STM 0x104A
#define TPM_PPI_VERSION_LEN 3
enum tpm_chip_flags {
TPM_CHIP_FLAG_REGISTERED = BIT(0),
TPM_CHIP_FLAG_TPM2 = BIT(1),
TPM_CHIP_FLAG_IRQ = BIT(2),
};
struct tpm_chip {
struct device dev;
struct cdev cdev;
/* A driver callback under ops cannot be run unless ops_sem is held
* (sometimes implicitly, eg for the sysfs code). ops becomes null
* when the driver is unregistered, see tpm_try_get_ops.
*/
struct rw_semaphore ops_sem;
const struct tpm_class_ops *ops;
unsigned int flags;
int dev_num; /* /dev/tpm# */
unsigned long is_open; /* only one allowed */
struct mutex tpm_mutex; /* tpm is processing */
unsigned long timeout_a; /* jiffies */
unsigned long timeout_b; /* jiffies */
unsigned long timeout_c; /* jiffies */
unsigned long timeout_d; /* jiffies */
bool timeout_adjusted;
unsigned long duration[3]; /* jiffies */
bool duration_adjusted;
struct dentry **bios_dir;
#ifdef CONFIG_ACPI
const struct attribute_group *groups[2];
unsigned int groups_cnt;
acpi_handle acpi_dev_handle;
char ppi_version[TPM_PPI_VERSION_LEN + 1];
#endif /* CONFIG_ACPI */
};
#define to_tpm_chip(d) container_of(d, struct tpm_chip, dev)
static inline int tpm_read_index(int base, int index)
{
outb(index, base);
return inb(base+1) & 0xFF;
}
static inline void tpm_write_index(int base, int index, int value)
{
outb(index, base);
outb(value & 0xFF, base+1);
}
struct tpm_input_header {
__be16 tag;
__be32 length;
__be32 ordinal;
} __packed;
struct tpm_output_header {
__be16 tag;
__be32 length;
__be32 return_code;
} __packed;
#define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
struct stclear_flags_t {
__be16 tag;
u8 deactivated;
u8 disableForceClear;
u8 physicalPresence;
u8 physicalPresenceLock;
u8 bGlobalLock;
} __packed;
struct tpm_version_t {
u8 Major;
u8 Minor;
u8 revMajor;
u8 revMinor;
} __packed;
struct tpm_version_1_2_t {
__be16 tag;
u8 Major;
u8 Minor;
u8 revMajor;
u8 revMinor;
} __packed;
struct timeout_t {
__be32 a;
__be32 b;
__be32 c;
__be32 d;
} __packed;
struct duration_t {
__be32 tpm_short;
__be32 tpm_medium;
__be32 tpm_long;
} __packed;
struct permanent_flags_t {
__be16 tag;
u8 disable;
u8 ownership;
u8 deactivated;
u8 readPubek;
u8 disableOwnerClear;
u8 allowMaintenance;
u8 physicalPresenceLifetimeLock;
u8 physicalPresenceHWEnable;
u8 physicalPresenceCMDEnable;
u8 CEKPUsed;
u8 TPMpost;
u8 TPMpostLock;
u8 FIPS;
u8 operator;
u8 enableRevokeEK;
u8 nvLocked;
u8 readSRKPub;
u8 tpmEstablished;
u8 maintenanceDone;
u8 disableFullDALogicInfo;
} __packed;
typedef union {
struct permanent_flags_t perm_flags;
struct stclear_flags_t stclear_flags;
bool owned;
__be32 num_pcrs;
struct tpm_version_t tpm_version;
struct tpm_version_1_2_t tpm_version_1_2;
__be32 manufacturer_id;
struct timeout_t timeout;
struct duration_t duration;
} cap_t;
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),
};
struct tpm_getcap_params_in {
__be32 cap;
__be32 subcap_size;
__be32 subcap;
} __packed;
struct tpm_getcap_params_out {
__be32 cap_size;
cap_t cap;
} __packed;
struct tpm_readpubek_params_out {
u8 algorithm[4];
u8 encscheme[2];
u8 sigscheme[2];
__be32 paramsize;
u8 parameters[12]; /*assuming RSA*/
__be32 keysize;
u8 modulus[256];
u8 checksum[20];
} __packed;
typedef union {
struct tpm_input_header in;
struct tpm_output_header out;
} tpm_cmd_header;
struct tpm_pcrread_out {
u8 pcr_result[TPM_DIGEST_SIZE];
} __packed;
struct tpm_pcrread_in {
__be32 pcr_idx;
} __packed;
struct tpm_pcrextend_in {
__be32 pcr_idx;
u8 hash[TPM_DIGEST_SIZE];
} __packed;
/* 128 bytes is an arbitrary cap. This could be as large as TPM_BUFSIZE - 18
* bytes, but 128 is still a relatively large number of random bytes and
* anything much bigger causes users of struct tpm_cmd_t to start getting
* compiler warnings about stack frame size. */
#define TPM_MAX_RNG_DATA 128
struct tpm_getrandom_out {
__be32 rng_data_len;
u8 rng_data[TPM_MAX_RNG_DATA];
} __packed;
struct tpm_getrandom_in {
__be32 num_bytes;
} __packed;
struct tpm_startup_in {
__be16 startup_type;
} __packed;
typedef union {
struct tpm_getcap_params_out getcap_out;
struct tpm_readpubek_params_out readpubek_out;
u8 readpubek_out_buffer[sizeof(struct tpm_readpubek_params_out)];
struct tpm_getcap_params_in getcap_in;
struct tpm_pcrread_in pcrread_in;
struct tpm_pcrread_out pcrread_out;
struct tpm_pcrextend_in pcrextend_in;
struct tpm_getrandom_in getrandom_in;
struct tpm_getrandom_out getrandom_out;
struct tpm_startup_in startup_in;
} tpm_cmd_params;
struct tpm_cmd_t {
tpm_cmd_header header;
tpm_cmd_params params;
} __packed;
/* A string buffer type for constructing TPM commands. This is based on the
* ideas of string buffer code in security/keys/trusted.h but is heap based
* in order to keep the stack usage minimal.
*/
enum tpm_buf_flags {
TPM_BUF_OVERFLOW = BIT(0),
};
struct tpm_buf {
struct page *data_page;
unsigned int flags;
u8 *data;
};
static inline int tpm_buf_init(struct tpm_buf *buf, u16 tag, u32 ordinal)
{
struct tpm_input_header *head;
buf->data_page = alloc_page(GFP_HIGHUSER);
if (!buf->data_page)
return -ENOMEM;
buf->flags = 0;
buf->data = kmap(buf->data_page);
head = (struct tpm_input_header *) buf->data;
head->tag = cpu_to_be16(tag);
head->length = cpu_to_be32(sizeof(*head));
head->ordinal = cpu_to_be32(ordinal);
return 0;
}
static inline void tpm_buf_destroy(struct tpm_buf *buf)
{
kunmap(buf->data_page);
__free_page(buf->data_page);
}
static inline u32 tpm_buf_length(struct tpm_buf *buf)
{
struct tpm_input_header *head = (struct tpm_input_header *) buf->data;
return be32_to_cpu(head->length);
}
static inline u16 tpm_buf_tag(struct tpm_buf *buf)
{
struct tpm_input_header *head = (struct tpm_input_header *) buf->data;
return be16_to_cpu(head->tag);
}
static inline void tpm_buf_append(struct tpm_buf *buf,
const unsigned char *new_data,
unsigned int new_len)
{
struct tpm_input_header *head = (struct tpm_input_header *) buf->data;
u32 len = tpm_buf_length(buf);
/* Return silently if overflow has already happened. */
if (buf->flags & TPM_BUF_OVERFLOW)
return;
if ((len + new_len) > PAGE_SIZE) {
WARN(1, "tpm_buf: overflow\n");
buf->flags |= TPM_BUF_OVERFLOW;
return;
}
memcpy(&buf->data[len], new_data, new_len);
head->length = cpu_to_be32(len + new_len);
}
static inline void tpm_buf_append_u8(struct tpm_buf *buf, const u8 value)
{
tpm_buf_append(buf, &value, 1);
}
static inline void tpm_buf_append_u16(struct tpm_buf *buf, const u16 value)
{
__be16 value2 = cpu_to_be16(value);
tpm_buf_append(buf, (u8 *) &value2, 2);
}
static inline void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value)
{
__be32 value2 = cpu_to_be32(value);
tpm_buf_append(buf, (u8 *) &value2, 4);
}
extern struct class *tpm_class;
extern dev_t tpm_devt;
extern const struct file_operations tpm_fops;
extern struct idr dev_nums_idr;
ssize_t tpm_getcap(struct device *, __be32, cap_t *, const char *);
ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
size_t bufsiz);
ssize_t tpm_transmit_cmd(struct tpm_chip *chip, void *cmd, int len,
const char *desc);
extern int tpm_get_timeouts(struct tpm_chip *);
extern void tpm_gen_interrupt(struct tpm_chip *);
extern int tpm_do_selftest(struct tpm_chip *);
extern unsigned long tpm_calc_ordinal_duration(struct tpm_chip *, u32);
extern int tpm_pm_suspend(struct device *);
extern int tpm_pm_resume(struct device *);
extern int wait_for_tpm_stat(struct tpm_chip *, u8, unsigned long,
wait_queue_head_t *, bool);
struct tpm_chip *tpm_chip_find_get(int chip_num);
__must_check int tpm_try_get_ops(struct tpm_chip *chip);
void tpm_put_ops(struct tpm_chip *chip);
extern struct tpm_chip *tpm_chip_alloc(struct device *dev,
const struct tpm_class_ops *ops);
extern struct tpm_chip *tpmm_chip_alloc(struct device *pdev,
const struct tpm_class_ops *ops);
extern int tpm_chip_register(struct tpm_chip *chip);
extern void tpm_chip_unregister(struct tpm_chip *chip);
int tpm_sysfs_add_device(struct tpm_chip *chip);
void tpm_sysfs_del_device(struct tpm_chip *chip);
int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf);
#ifdef CONFIG_ACPI
extern void tpm_add_ppi(struct tpm_chip *chip);
#else
static inline void tpm_add_ppi(struct tpm_chip *chip)
{
}
#endif
int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf);
int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash);
int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max);
int tpm2_seal_trusted(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options);
int tpm2_unseal_trusted(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options);
ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,
u32 *value, const char *desc);
extern int tpm2_startup(struct tpm_chip *chip, u16 startup_type);
extern void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type);
extern unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *, u32);
extern int tpm2_do_selftest(struct tpm_chip *chip);
extern int tpm2_gen_interrupt(struct tpm_chip *chip);
extern int tpm2_probe(struct tpm_chip *chip);