tpm/tpm_ftpm_tee: A driver for firmware TPM running inside TEE
Add a driver for a firmware TPM running inside TEE. Documentation of the firmware TPM: https://www.microsoft.com/en-us/research/publication/ftpm-software-implementation-tpm-chip/ . Implementation of the firmware TPM: https://github.com/Microsoft/ms-tpm-20-ref/tree/master/Samples/ARM32-FirmwareTPM Tested-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Tested-by: Thirupathaiah Annapureddy <thiruan@microsoft.com> Signed-off-by: Thirupathaiah Annapureddy <thiruan@microsoft.com> Co-authored-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
This commit is contained in:
Sasha Levin
Jarkko Sakkinen
Родитель
28eba2fddd
Коммит
09e574831b
|
|
@ -575,6 +575,8 @@ patternProperties:
|
|||
description: Micro Crystal AG
|
||||
"^micron,.*":
|
||||
description: Micron Technology Inc.
|
||||
"^microsoft,.*":
|
||||
description: Microsoft Corporation
|
||||
"^mikroe,.*":
|
||||
description: MikroElektronika d.o.o.
|
||||
"^miniand,.*":
|
||||
|
|
|
|||
|
|
@ -164,6 +164,11 @@ config TCG_VTPM_PROXY
|
|||
/dev/vtpmX and a server-side file descriptor on which the vTPM
|
||||
can receive commands.
|
||||
|
||||
config TCG_FTPM_TEE
|
||||
tristate "TEE based fTPM Interface"
|
||||
depends on TEE && OPTEE
|
||||
help
|
||||
This driver proxies for firmware TPM running in TEE.
|
||||
|
||||
source "drivers/char/tpm/st33zp24/Kconfig"
|
||||
endif # TCG_TPM
|
||||
|
|
|
|||
|
|
@ -33,3 +33,4 @@ obj-$(CONFIG_TCG_TIS_ST33ZP24) += st33zp24/
|
|||
obj-$(CONFIG_TCG_XEN) += xen-tpmfront.o
|
||||
obj-$(CONFIG_TCG_CRB) += tpm_crb.o
|
||||
obj-$(CONFIG_TCG_VTPM_PROXY) += tpm_vtpm_proxy.o
|
||||
obj-$(CONFIG_TCG_FTPM_TEE) += tpm_ftpm_tee.o
|
||||
|
|
|
|||
|
|
@ -0,0 +1,350 @@
|
|||
// SPDX-License-Identifier: GPL-2.0
|
||||
/*
|
||||
* Copyright (C) Microsoft Corporation
|
||||
*
|
||||
* Implements a firmware TPM as described here:
|
||||
* https://www.microsoft.com/en-us/research/publication/ftpm-software-implementation-tpm-chip/
|
||||
*
|
||||
* A reference implementation is available here:
|
||||
* https://github.com/microsoft/ms-tpm-20-ref/tree/master/Samples/ARM32-FirmwareTPM/optee_ta/fTPM
|
||||
*/
|
||||
|
||||
#include <linux/acpi.h>
|
||||
#include <linux/of.h>
|
||||
#include <linux/of_platform.h>
|
||||
#include <linux/platform_device.h>
|
||||
#include <linux/tee_drv.h>
|
||||
#include <linux/tpm.h>
|
||||
#include <linux/uuid.h>
|
||||
|
||||
#include "tpm.h"
|
||||
#include "tpm_ftpm_tee.h"
|
||||
|
||||
/*
|
||||
* TA_FTPM_UUID: BC50D971-D4C9-42C4-82CB-343FB7F37896
|
||||
*
|
||||
* Randomly generated, and must correspond to the GUID on the TA side.
|
||||
* Defined here in the reference implementation:
|
||||
* https://github.com/microsoft/ms-tpm-20-ref/blob/master/Samples/ARM32-FirmwareTPM/optee_ta/fTPM/include/fTPM.h#L42
|
||||
*/
|
||||
static const uuid_t ftpm_ta_uuid =
|
||||
UUID_INIT(0xBC50D971, 0xD4C9, 0x42C4,
|
||||
0x82, 0xCB, 0x34, 0x3F, 0xB7, 0xF3, 0x78, 0x96);
|
||||
|
||||
/**
|
||||
* ftpm_tee_tpm_op_recv - retrieve fTPM response.
|
||||
* @chip: the tpm_chip description as specified in driver/char/tpm/tpm.h.
|
||||
* @buf: the buffer to store data.
|
||||
* @count: the number of bytes to read.
|
||||
*
|
||||
* Return:
|
||||
* In case of success the number of bytes received.
|
||||
* On failure, -errno.
|
||||
*/
|
||||
static int ftpm_tee_tpm_op_recv(struct tpm_chip *chip, u8 *buf, size_t count)
|
||||
{
|
||||
struct ftpm_tee_private *pvt_data = dev_get_drvdata(chip->dev.parent);
|
||||
size_t len;
|
||||
|
||||
len = pvt_data->resp_len;
|
||||
if (count < len) {
|
||||
dev_err(&chip->dev,
|
||||
"%s: Invalid size in recv: count=%zd, resp_len=%zd\n",
|
||||
__func__, count, len);
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
memcpy(buf, pvt_data->resp_buf, len);
|
||||
pvt_data->resp_len = 0;
|
||||
|
||||
return len;
|
||||
}
|
||||
|
||||
/**
|
||||
* ftpm_tee_tpm_op_send - send TPM commands through the TEE shared memory.
|
||||
* @chip: the tpm_chip description as specified in driver/char/tpm/tpm.h
|
||||
* @buf: the buffer to send.
|
||||
* @len: the number of bytes to send.
|
||||
*
|
||||
* Return:
|
||||
* In case of success, returns 0.
|
||||
* On failure, -errno
|
||||
*/
|
||||
static int ftpm_tee_tpm_op_send(struct tpm_chip *chip, u8 *buf, size_t len)
|
||||
{
|
||||
struct ftpm_tee_private *pvt_data = dev_get_drvdata(chip->dev.parent);
|
||||
size_t resp_len;
|
||||
int rc;
|
||||
u8 *temp_buf;
|
||||
struct tpm_header *resp_header;
|
||||
struct tee_ioctl_invoke_arg transceive_args;
|
||||
struct tee_param command_params[4];
|
||||
struct tee_shm *shm = pvt_data->shm;
|
||||
|
||||
if (len > MAX_COMMAND_SIZE) {
|
||||
dev_err(&chip->dev,
|
||||
"%s: len=%zd exceeds MAX_COMMAND_SIZE supported by fTPM TA\n",
|
||||
__func__, len);
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
memset(&transceive_args, 0, sizeof(transceive_args));
|
||||
memset(command_params, 0, sizeof(command_params));
|
||||
pvt_data->resp_len = 0;
|
||||
|
||||
/* Invoke FTPM_OPTEE_TA_SUBMIT_COMMAND function of fTPM TA */
|
||||
transceive_args = (struct tee_ioctl_invoke_arg) {
|
||||
.func = FTPM_OPTEE_TA_SUBMIT_COMMAND,
|
||||
.session = pvt_data->session,
|
||||
.num_params = 4,
|
||||
};
|
||||
|
||||
/* Fill FTPM_OPTEE_TA_SUBMIT_COMMAND parameters */
|
||||
command_params[0] = (struct tee_param) {
|
||||
.attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT,
|
||||
.u.memref = {
|
||||
.shm = shm,
|
||||
.size = len,
|
||||
.shm_offs = 0,
|
||||
},
|
||||
};
|
||||
|
||||
temp_buf = tee_shm_get_va(shm, 0);
|
||||
if (IS_ERR(temp_buf)) {
|
||||
dev_err(&chip->dev, "%s: tee_shm_get_va failed for transmit\n",
|
||||
__func__);
|
||||
return PTR_ERR(temp_buf);
|
||||
}
|
||||
memset(temp_buf, 0, (MAX_COMMAND_SIZE + MAX_RESPONSE_SIZE));
|
||||
memcpy(temp_buf, buf, len);
|
||||
|
||||
command_params[1] = (struct tee_param) {
|
||||
.attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT,
|
||||
.u.memref = {
|
||||
.shm = shm,
|
||||
.size = MAX_RESPONSE_SIZE,
|
||||
.shm_offs = MAX_COMMAND_SIZE,
|
||||
},
|
||||
};
|
||||
|
||||
rc = tee_client_invoke_func(pvt_data->ctx, &transceive_args,
|
||||
command_params);
|
||||
if ((rc < 0) || (transceive_args.ret != 0)) {
|
||||
dev_err(&chip->dev, "%s: SUBMIT_COMMAND invoke error: 0x%x\n",
|
||||
__func__, transceive_args.ret);
|
||||
return (rc < 0) ? rc : transceive_args.ret;
|
||||
}
|
||||
|
||||
temp_buf = tee_shm_get_va(shm, command_params[1].u.memref.shm_offs);
|
||||
if (IS_ERR(temp_buf)) {
|
||||
dev_err(&chip->dev, "%s: tee_shm_get_va failed for receive\n",
|
||||
__func__);
|
||||
return PTR_ERR(temp_buf);
|
||||
}
|
||||
|
||||
resp_header = (struct tpm_header *)temp_buf;
|
||||
resp_len = be32_to_cpu(resp_header->length);
|
||||
|
||||
/* sanity check resp_len */
|
||||
if (resp_len < TPM_HEADER_SIZE) {
|
||||
dev_err(&chip->dev, "%s: tpm response header too small\n",
|
||||
__func__);
|
||||
return -EIO;
|
||||
}
|
||||
if (resp_len > MAX_RESPONSE_SIZE) {
|
||||
dev_err(&chip->dev,
|
||||
"%s: resp_len=%zd exceeds MAX_RESPONSE_SIZE\n",
|
||||
__func__, resp_len);
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
/* sanity checks look good, cache the response */
|
||||
memcpy(pvt_data->resp_buf, temp_buf, resp_len);
|
||||
pvt_data->resp_len = resp_len;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void ftpm_tee_tpm_op_cancel(struct tpm_chip *chip)
|
||||
{
|
||||
/* not supported */
|
||||
}
|
||||
|
||||
static u8 ftpm_tee_tpm_op_status(struct tpm_chip *chip)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
static bool ftpm_tee_tpm_req_canceled(struct tpm_chip *chip, u8 status)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct tpm_class_ops ftpm_tee_tpm_ops = {
|
||||
.flags = TPM_OPS_AUTO_STARTUP,
|
||||
.recv = ftpm_tee_tpm_op_recv,
|
||||
.send = ftpm_tee_tpm_op_send,
|
||||
.cancel = ftpm_tee_tpm_op_cancel,
|
||||
.status = ftpm_tee_tpm_op_status,
|
||||
.req_complete_mask = 0,
|
||||
.req_complete_val = 0,
|
||||
.req_canceled = ftpm_tee_tpm_req_canceled,
|
||||
};
|
||||
|
||||
/*
|
||||
* Check whether this driver supports the fTPM TA in the TEE instance
|
||||
* represented by the params (ver/data) to this function.
|
||||
*/
|
||||
static int ftpm_tee_match(struct tee_ioctl_version_data *ver, const void *data)
|
||||
{
|
||||
/*
|
||||
* Currently this driver only support GP Complaint OPTEE based fTPM TA
|
||||
*/
|
||||
if ((ver->impl_id == TEE_IMPL_ID_OPTEE) &&
|
||||
(ver->gen_caps & TEE_GEN_CAP_GP))
|
||||
return 1;
|
||||
else
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* ftpm_tee_probe - initialize the fTPM
|
||||
* @pdev: the platform_device description.
|
||||
*
|
||||
* Return:
|
||||
* On success, 0. On failure, -errno.
|
||||
*/
|
||||
static int ftpm_tee_probe(struct platform_device *pdev)
|
||||
{
|
||||
int rc;
|
||||
struct tpm_chip *chip;
|
||||
struct device *dev = &pdev->dev;
|
||||
struct ftpm_tee_private *pvt_data = NULL;
|
||||
struct tee_ioctl_open_session_arg sess_arg;
|
||||
|
||||
pvt_data = devm_kzalloc(dev, sizeof(struct ftpm_tee_private),
|
||||
GFP_KERNEL);
|
||||
if (!pvt_data)
|
||||
return -ENOMEM;
|
||||
|
||||
dev_set_drvdata(dev, pvt_data);
|
||||
|
||||
/* Open context with TEE driver */
|
||||
pvt_data->ctx = tee_client_open_context(NULL, ftpm_tee_match, NULL,
|
||||
NULL);
|
||||
if (IS_ERR(pvt_data->ctx)) {
|
||||
if (PTR_ERR(pvt_data->ctx) == -ENOENT)
|
||||
return -EPROBE_DEFER;
|
||||
dev_err(dev, "%s: tee_client_open_context failed\n", __func__);
|
||||
return PTR_ERR(pvt_data->ctx);
|
||||
}
|
||||
|
||||
/* Open a session with fTPM TA */
|
||||
memset(&sess_arg, 0, sizeof(sess_arg));
|
||||
memcpy(sess_arg.uuid, ftpm_ta_uuid.b, TEE_IOCTL_UUID_LEN);
|
||||
sess_arg.clnt_login = TEE_IOCTL_LOGIN_PUBLIC;
|
||||
sess_arg.num_params = 0;
|
||||
|
||||
rc = tee_client_open_session(pvt_data->ctx, &sess_arg, NULL);
|
||||
if ((rc < 0) || (sess_arg.ret != 0)) {
|
||||
dev_err(dev, "%s: tee_client_open_session failed, err=%x\n",
|
||||
__func__, sess_arg.ret);
|
||||
rc = -EINVAL;
|
||||
goto out_tee_session;
|
||||
}
|
||||
pvt_data->session = sess_arg.session;
|
||||
|
||||
/* Allocate dynamic shared memory with fTPM TA */
|
||||
pvt_data->shm = tee_shm_alloc(pvt_data->ctx,
|
||||
MAX_COMMAND_SIZE + MAX_RESPONSE_SIZE,
|
||||
TEE_SHM_MAPPED | TEE_SHM_DMA_BUF);
|
||||
if (IS_ERR(pvt_data->shm)) {
|
||||
dev_err(dev, "%s: tee_shm_alloc failed\n", __func__);
|
||||
rc = -ENOMEM;
|
||||
goto out_shm_alloc;
|
||||
}
|
||||
|
||||
/* Allocate new struct tpm_chip instance */
|
||||
chip = tpm_chip_alloc(dev, &ftpm_tee_tpm_ops);
|
||||
if (IS_ERR(chip)) {
|
||||
dev_err(dev, "%s: tpm_chip_alloc failed\n", __func__);
|
||||
rc = PTR_ERR(chip);
|
||||
goto out_chip_alloc;
|
||||
}
|
||||
|
||||
pvt_data->chip = chip;
|
||||
pvt_data->chip->flags |= TPM_CHIP_FLAG_TPM2;
|
||||
|
||||
/* Create a character device for the fTPM */
|
||||
rc = tpm_chip_register(pvt_data->chip);
|
||||
if (rc) {
|
||||
dev_err(dev, "%s: tpm_chip_register failed with rc=%d\n",
|
||||
__func__, rc);
|
||||
goto out_chip;
|
||||
}
|
||||
|
||||
return 0;
|
||||
|
||||
out_chip:
|
||||
put_device(&pvt_data->chip->dev);
|
||||
out_chip_alloc:
|
||||
tee_shm_free(pvt_data->shm);
|
||||
out_shm_alloc:
|
||||
tee_client_close_session(pvt_data->ctx, pvt_data->session);
|
||||
out_tee_session:
|
||||
tee_client_close_context(pvt_data->ctx);
|
||||
|
||||
return rc;
|
||||
}
|
||||
|
||||
/**
|
||||
* ftpm_tee_remove - remove the TPM device
|
||||
* @pdev: the platform_device description.
|
||||
*
|
||||
* Return:
|
||||
* 0 always.
|
||||
*/
|
||||
static int ftpm_tee_remove(struct platform_device *pdev)
|
||||
{
|
||||
struct ftpm_tee_private *pvt_data = dev_get_drvdata(&pdev->dev);
|
||||
|
||||
/* Release the chip */
|
||||
tpm_chip_unregister(pvt_data->chip);
|
||||
|
||||
/* frees chip */
|
||||
put_device(&pvt_data->chip->dev);
|
||||
|
||||
/* Free the shared memory pool */
|
||||
tee_shm_free(pvt_data->shm);
|
||||
|
||||
/* close the existing session with fTPM TA*/
|
||||
tee_client_close_session(pvt_data->ctx, pvt_data->session);
|
||||
|
||||
/* close the context with TEE driver */
|
||||
tee_client_close_context(pvt_data->ctx);
|
||||
|
||||
/* memory allocated with devm_kzalloc() is freed automatically */
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct of_device_id of_ftpm_tee_ids[] = {
|
||||
{ .compatible = "microsoft,ftpm" },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(of, of_ftpm_tee_ids);
|
||||
|
||||
static struct platform_driver ftpm_tee_driver = {
|
||||
.driver = {
|
||||
.name = "ftpm-tee",
|
||||
.of_match_table = of_match_ptr(of_ftpm_tee_ids),
|
||||
},
|
||||
.probe = ftpm_tee_probe,
|
||||
.remove = ftpm_tee_remove,
|
||||
};
|
||||
|
||||
module_platform_driver(ftpm_tee_driver);
|
||||
|
||||
MODULE_AUTHOR("Thirupathaiah Annapureddy <thiruan@microsoft.com>");
|
||||
MODULE_DESCRIPTION("TPM Driver for fTPM TA in TEE");
|
||||
MODULE_LICENSE("GPL v2");
|
||||
|
|
@ -0,0 +1,40 @@
|
|||
/* SPDX-License-Identifier: GPL-2.0 */
|
||||
/*
|
||||
* Copyright (C) Microsoft Corporation
|
||||
*/
|
||||
|
||||
#ifndef __TPM_FTPM_TEE_H__
|
||||
#define __TPM_FTPM_TEE_H__
|
||||
|
||||
#include <linux/tee_drv.h>
|
||||
#include <linux/tpm.h>
|
||||
#include <linux/uuid.h>
|
||||
|
||||
/* The TAFs ID implemented in this TA */
|
||||
#define FTPM_OPTEE_TA_SUBMIT_COMMAND (0)
|
||||
#define FTPM_OPTEE_TA_EMULATE_PPI (1)
|
||||
|
||||
/* max. buffer size supported by fTPM */
|
||||
#define MAX_COMMAND_SIZE 4096
|
||||
#define MAX_RESPONSE_SIZE 4096
|
||||
|
||||
/**
|
||||
* struct ftpm_tee_private - fTPM's private data
|
||||
* @chip: struct tpm_chip instance registered with tpm framework.
|
||||
* @state: internal state
|
||||
* @session: fTPM TA session identifier.
|
||||
* @resp_len: cached response buffer length.
|
||||
* @resp_buf: cached response buffer.
|
||||
* @ctx: TEE context handler.
|
||||
* @shm: Memory pool shared with fTPM TA in TEE.
|
||||
*/
|
||||
struct ftpm_tee_private {
|
||||
struct tpm_chip *chip;
|
||||
u32 session;
|
||||
size_t resp_len;
|
||||
u8 resp_buf[MAX_RESPONSE_SIZE];
|
||||
struct tee_context *ctx;
|
||||
struct tee_shm *shm;
|
||||
};
|
||||
|
||||
#endif /* __TPM_FTPM_TEE_H__ */
|
||||
Загрузка…
Ссылка в новой задаче