Add a TPM chip driver for platforms where a TPM 2.0 instance is implemented by a Trusted Application (TA) running in Qualcomm's Trusted Execution Environment (QTEE), reachable over the QCOMTEE object-IPC transport.

The driver discovers the qcom.tz.tpm TEE-bus device, opens a session with the TPM TA, and register with tpm interface. This exposes the TA through the standard /dev/tpm interface and the existing tpm2 command layer. OS need not be aware underlying TPM instance is dTPM or fTPM.

Signed-off-by: Kuldeep Singh kuldeep.singh@oss.qualcomm.com --- drivers/char/tpm/Kconfig | 9 + drivers/char/tpm/Makefile | 1 + drivers/char/tpm/tpm_qcom.c | 413 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 423 insertions(+)

diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig index 5f672f2c01b0..05d704ed3632 100644 --- a/drivers/char/tpm/Kconfig +++ b/drivers/char/tpm/Kconfig @@ -243,6 +243,15 @@ config TCG_FTPM_TEE help This driver proxies for firmware TPM running in TEE.

+config TCG_QCOM + tristate "Qualcomm TEE based TPM Interface" + depends on QCOMTEE + help + This driver provides interface to run TPM instances with Trustzone + having Qualcomm TPM TA running in Qualcomm TEE. + The mechanism uses the object-IPC based transport provided by + QCOMTEE. + config TCG_SVSM tristate "SNP SVSM vTPM interface" depends on AMD_MEM_ENCRYPT diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile index 5b5cdc0d32e4..471cbf49afd2 100644 --- a/drivers/char/tpm/Makefile +++ b/drivers/char/tpm/Makefile @@ -45,5 +45,6 @@ obj-$(CONFIG_TCG_CRB) += tpm_crb.o obj-$(CONFIG_TCG_ARM_CRB_FFA) += tpm_crb_ffa.o obj-$(CONFIG_TCG_VTPM_PROXY) += tpm_vtpm_proxy.o obj-$(CONFIG_TCG_FTPM_TEE) += tpm_ftpm_tee.o +obj-$(CONFIG_TCG_QCOM) += tpm_qcom.o obj-$(CONFIG_TCG_SVSM) += tpm_svsm.o obj-$(CONFIG_TCG_LOONGSON) += tpm_loongson.o diff --git a/drivers/char/tpm/tpm_qcom.c b/drivers/char/tpm/tpm_qcom.c new file mode 100644 index 000000000000..0fe0104e8b5a --- /dev/null +++ b/drivers/char/tpm/tpm_qcom.c @@ -0,0 +1,413 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries. + * + */ + +#include <linux/bitfield.h> +#include <linux/mm.h> +#include <linux/slab.h> +#include <linux/tee.h> +#include <linux/tee_drv.h> +#include <linux/tpm.h> +#include <linux/uuid.h> + +#include "tpm.h" + +#define QCOMTEE_ROOT_OP_REG_WITH_CREDENTIALS 5 +#define QCOMTEE_OP_CLIENT_ENV_OPEN 0 +#define QCOMTEE_MSG_OBJECT_OP_MASK GENMASK(15, 0) +#define QCOMTEE_MSG_OBJECT_OP_RELEASE (QCOMTEE_MSG_OBJECT_OP_MASK - 0) + +#define QCOMTEE_TPM_OP_SEND_COMMAND 0 + +/* UID of the "qcom.tz.tpm" service */ +#define QCOMTEE_TPM_UID 81 + +/* Max buffer size supported by TPM TA */ +#define TPM_QCOM_MAX_COMMAND_SIZE SZ_4K +#define TPM_QCOM_MAX_RESPONSE_SIZE SZ_4K + +#define QCOMTEE_TPM_GET_TA_VERSION_ID 0x0001000 +#define QCOMTEE_TPM_TA_VERSION_MAJOR GENMASK(31, 16) +#define QCOMTEE_TPM_TA_VERSION_MINOR GENMASK(15, 0) + +struct tpm_qcom_ta_version_req { + u32 command_id; +} __packed; + +struct tpm_qcom_ta_version_resp { + u32 status; + u32 command_id; + u32 version_num; +} __packed; + +#define QCOMTEE_TPM_TYPE_ID 0x0080000 +#define QCOMTEE_TPM_TYPE_DTPM 0x6454504dU +#define QCOMTEE_TPM_TYPE_FTPM 0x6654504dU +#define QCOMTEE_TPM_TYPE_NONE 0x4e6f6e65U + +struct tpm_qcom_type_req { + u32 command_id; +} __packed; + +struct tpm_qcom_type_resp { + u32 command_id; + u32 status; + u32 tpm_type; +} __packed; + +/* + * dTPM SPI transfer optimization: + * TRANSFER_START before a burst of commands, TRANSFER_END once done. + */ +#define QCOMTEE_TPM_TRANSFER_ID 0x0000002 +#define QCOMTEE_TPM_TRANSFER_END 0 +#define QCOMTEE_TPM_TRANSFER_START 1 + +struct tpm_qcom_transfer_req { + u32 command_id; + u32 transfer_state; +} __packed; + +struct tpm_qcom_transfer_resp { + u32 command_id; + u32 status; +} __packed; + +struct tpm_qcom_private { + struct tpm_chip *chip; + struct device *dev; + struct tee_context *ctx; + struct tee_param_objref tpm_svc_obj; + bool is_dtpm; +}; + +/* UUID of the QTEE-bus device representing the TPM TA. */ +static const uuid_t tpm_qcom_uuid = + UUID_INIT(0xaabcb593, 0x7083, 0x5536, + 0xac, 0x27, 0x3d, 0x2d, 0x89, 0x41, 0x9d, 0xdb); + +static void tpm_qcom_release_object(struct tee_context *ctx, + struct tee_param_objref object) +{ + struct tee_ioctl_object_invoke_arg inv_arg = {}; + + inv_arg.id = object.id; + inv_arg.op = QCOMTEE_MSG_OBJECT_OP_RELEASE; + inv_arg.num_params = 0; + + tee_client_object_invoke_func(ctx, &inv_arg, NULL); +} + +static int tpm_qcom_get_client_env_obj(struct device *dev, + struct tee_context *ctx, + struct tee_param_objref *client_env_obj) +{ + struct tee_ioctl_object_invoke_arg inv_arg = {}; + struct tee_param param[2] = {}; + int ret; + + inv_arg.id = TEE_OBJREF_NULL; + inv_arg.op = QCOMTEE_ROOT_OP_REG_WITH_CREDENTIALS; + inv_arg.num_params = 2; + + param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_OBJREF_INPUT; + param[0].u.objref.id = TEE_OBJREF_NULL; + param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_OBJREF_OUTPUT; + + ret = tee_client_object_invoke_func(ctx, &inv_arg, param); + if (ret < 0 || inv_arg.ret != 0) { + dev_err(dev, "get client env obj failed: ret=%d, invoke_ret=0x%x\n", + ret, inv_arg.ret); + return -EINVAL; + } + + *client_env_obj = param[1].u.objref; + return 0; +} + +static int tpm_qcom_get_svc_obj(struct device *dev, + struct tee_context *ctx, + struct tee_param_objref client_env_obj, + struct tee_param_objref *tpm_svc_obj) +{ + struct tee_ioctl_object_invoke_arg inv_arg = {}; + struct tee_param param[2] = {}; + u32 tpm_uid = QCOMTEE_TPM_UID; + int ret; + + inv_arg.id = client_env_obj.id; + inv_arg.op = QCOMTEE_OP_CLIENT_ENV_OPEN; + inv_arg.num_params = 2; + + param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_UBUF_INPUT; + param[0].u.ubuf = (struct tee_param_ubuf){ .addr = &tpm_uid, + .size = sizeof(tpm_uid) }; + param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_OBJREF_OUTPUT; + + ret = tee_client_object_invoke_func(ctx, &inv_arg, param); + if (ret < 0 || inv_arg.ret != 0) { + dev_err(dev, "get TPM service obj failed: ret=%d, invoke_ret=0x%x\n", + ret, inv_arg.ret); + return -EINVAL; + } + + *tpm_svc_obj = param[1].u.objref; + return 0; +} + +static int tpm_qcom_send_command(struct tpm_qcom_private *pvt_data, + void *req, size_t req_len, void *resp, + size_t *resp_len) +{ + struct tee_ioctl_object_invoke_arg inv_arg = {}; + struct tee_param param[3] = {}; + u8 locality_arg = 0; + int ret; + + inv_arg.id = pvt_data->tpm_svc_obj.id; + inv_arg.op = QCOMTEE_TPM_OP_SEND_COMMAND; + inv_arg.num_params = 3; + + param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_UBUF_INPUT; + param[0].u.ubuf = (struct tee_param_ubuf){ .addr = &locality_arg, + .size = sizeof(locality_arg) }; + param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_UBUF_INPUT; + param[1].u.ubuf = (struct tee_param_ubuf){ .addr = req, .size = req_len }; + param[2].attr = TEE_IOCTL_PARAM_ATTR_TYPE_UBUF_OUTPUT; + param[2].u.ubuf = (struct tee_param_ubuf){ .addr = resp, .size = *resp_len }; + + ret = tee_client_object_invoke_func(pvt_data->ctx, &inv_arg, param); + if (ret < 0 || inv_arg.ret != 0) { + dev_err(pvt_data->dev, + "send_command invoke ret: %d, err: 0x%x\n", + ret, inv_arg.ret); + return ret ?: -EINVAL; + } + + *resp_len = param[2].u.ubuf.size; + + return 0; +} + +static int tpm_qcom_get_ta_details(struct tpm_qcom_private *pvt_data) +{ + struct tpm_qcom_ta_version_req ver_req = { + .command_id = QCOMTEE_TPM_GET_TA_VERSION_ID, + }; + struct tpm_qcom_ta_version_resp ver_resp; + size_t resp_len = sizeof(ver_resp); + struct tpm_qcom_type_req type_req = { + .command_id = QCOMTEE_TPM_TYPE_ID, + }; + struct tpm_qcom_type_resp type_resp; + int ret; + + ret = tpm_qcom_send_command(pvt_data, &ver_req, sizeof(ver_req), + &ver_resp, &resp_len); + if (ret < 0 || resp_len < sizeof(ver_resp) || ver_resp.status != 0) + return ret ?: -EIO; + + dev_info(pvt_data->dev, "TPM TA version %u.%u\n", + FIELD_GET(QCOMTEE_TPM_TA_VERSION_MAJOR, ver_resp.version_num), + FIELD_GET(QCOMTEE_TPM_TA_VERSION_MINOR, ver_resp.version_num)); + + resp_len = sizeof(type_resp); + ret = tpm_qcom_send_command(pvt_data, &type_req, sizeof(type_req), + &type_resp, &resp_len); + if (ret < 0 || resp_len < sizeof(type_resp) || type_resp.status != 0) + return ret ?: -EIO; + + switch (type_resp.tpm_type) { + case QCOMTEE_TPM_TYPE_FTPM: + dev_info(pvt_data->dev, "TPM type: fTPM\n"); + pvt_data->is_dtpm = false; + break; + case QCOMTEE_TPM_TYPE_DTPM: + dev_info(pvt_data->dev, "TPM type: dTPM\n"); + pvt_data->is_dtpm = true; + break; + default: + dev_err(pvt_data->dev, "unsupported TPM type: 0x%08x\n", + type_resp.tpm_type); + return -EIO; + } + + return 0; +} + +/* fTPM does not implement this command and to be invoked via dtpm only. */ +static void tpm_qcom_transfer(struct tpm_qcom_private *pvt_data, + u32 transfer_state) +{ + struct tpm_qcom_transfer_req req = { + .command_id = QCOMTEE_TPM_TRANSFER_ID, + .transfer_state = transfer_state, + }; + struct tpm_qcom_transfer_resp resp; + size_t resp_len = sizeof(resp); + + tpm_qcom_send_command(pvt_data, &req, sizeof(req), &resp, &resp_len); +} + +static int tpm_qcom_cmd_ready(struct tpm_chip *chip) +{ + struct tpm_qcom_private *pvt_data = dev_get_drvdata(chip->dev.parent); + + if (pvt_data->is_dtpm) + tpm_qcom_transfer(pvt_data, QCOMTEE_TPM_TRANSFER_START); + + return 0; +} + +static int tpm_qcom_go_idle(struct tpm_chip *chip) +{ + struct tpm_qcom_private *pvt_data = dev_get_drvdata(chip->dev.parent); + + if (pvt_data->is_dtpm) + tpm_qcom_transfer(pvt_data, QCOMTEE_TPM_TRANSFER_END); + + return 0; +} + +/* + * The raw TPM2 command in @buf is sent directly as send_command's UBUF-in + * param and the raw TPM2 response is read back from its UBUF-out param. + */ +static int tpm_qcom_send(struct tpm_chip *chip, u8 *buf, size_t bufsiz, + size_t cmd_len) +{ + struct tpm_qcom_private *pvt_data = dev_get_drvdata(chip->dev.parent); + struct tpm_header *header = (struct tpm_header *)buf; + size_t resp_len = PAGE_ALIGN(TPM_QCOM_MAX_RESPONSE_SIZE); + size_t copy_len; + int ret; + + if (cmd_len > TPM_QCOM_MAX_COMMAND_SIZE) { + dev_err(&chip->dev, "len=%zd exceeds TPM_QCOM_MAX_COMMAND_SIZE\n", + cmd_len); + return -EIO; + } + + u8 *response __free(kfree) = kzalloc(resp_len, GFP_KERNEL); + if (!response) + return -ENOMEM; + + ret = tpm_qcom_send_command(pvt_data, buf, cmd_len, response, &resp_len); + if (ret < 0) { + dev_err(&chip->dev, "TPM command failed: cmd_len=%zu, tpm_cc=0x%08x, ret:%d\n", + cmd_len, be32_to_cpu(header->ordinal), ret); + return ret; + } + + copy_len = min_t(size_t, bufsiz, resp_len); + memcpy(buf, response, copy_len); + + return copy_len; +} + +static const struct tpm_class_ops tpm_qcom_ops = { + .flags = TPM_OPS_AUTO_STARTUP, + .send = tpm_qcom_send, + .cmd_ready = tpm_qcom_cmd_ready, + .go_idle = tpm_qcom_go_idle, +}; + +static int tpm_qcom_ctx_match(struct tee_ioctl_version_data *ver, + const void *data) +{ + return (ver->impl_id == TEE_IMPL_ID_QTEE); +} + +static int tpm_qcom_probe(struct tee_client_device *tee_dev) +{ + struct device *dev = &tee_dev->dev; + struct tpm_qcom_private *pvt_data; + struct tee_param_objref client_env_obj; + struct tee_param_objref tpm_svc_obj; + struct tpm_chip *chip; + int err; + + pvt_data = devm_kzalloc(dev, sizeof(*pvt_data), GFP_KERNEL); + if (!pvt_data) + return -ENOMEM; + + dev_set_drvdata(dev, pvt_data); + + pvt_data->ctx = tee_client_open_context(NULL, tpm_qcom_ctx_match, NULL, NULL); + if (IS_ERR(pvt_data->ctx)) + return -ENODEV; + + err = tpm_qcom_get_client_env_obj(dev, pvt_data->ctx, &client_env_obj); + if (err) + goto out_ctx; + + err = tpm_qcom_get_svc_obj(dev, pvt_data->ctx, client_env_obj, &tpm_svc_obj); + /* Release client_env object irrespective of service obj return status */ + tpm_qcom_release_object(pvt_data->ctx, client_env_obj); + if (err) + goto out_ctx; + + pvt_data->tpm_svc_obj = tpm_svc_obj; + pvt_data->dev = dev; + + err = tpm_qcom_get_ta_details(pvt_data); + if (err) + goto out_svc_obj; + + chip = tpmm_chip_alloc(dev, &tpm_qcom_ops); + if (IS_ERR(chip)) { + dev_err(dev, "tpmm_chip_alloc failed\n"); + err = PTR_ERR(chip); + goto out_svc_obj; + } + + pvt_data->chip = chip; + dev_set_drvdata(dev, pvt_data); + pvt_data->chip->flags |= TPM_CHIP_FLAG_TPM2 | TPM_CHIP_FLAG_SYNC; + + err = tpm_chip_register(pvt_data->chip); + if (err) { + dev_err(dev, "tpm_chip_register failed with rc=%d\n", err); + goto out_svc_obj; + } + + return 0; + +out_svc_obj: + tpm_qcom_release_object(pvt_data->ctx, tpm_svc_obj); +out_ctx: + tee_client_close_context(pvt_data->ctx); + return err; +} + +static void tpm_qcom_remove(struct tee_client_device *tee_dev) +{ + struct tpm_qcom_private *pvt_data = dev_get_drvdata(&tee_dev->dev); + + tpm_chip_unregister(pvt_data->chip); + tpm_qcom_release_object(pvt_data->ctx, pvt_data->tpm_svc_obj); + tee_client_close_context(pvt_data->ctx); +} + +static const struct tee_client_device_id tpm_qcom_id_table[] = { + { tpm_qcom_uuid }, + {} +}; +MODULE_DEVICE_TABLE(tee, tpm_qcom_id_table); + +static struct tee_client_driver tpm_qcom_driver = { + .id_table = tpm_qcom_id_table, + .probe = tpm_qcom_probe, + .remove = tpm_qcom_remove, + .driver = { + .name = "tpm_qcom", + }, +}; + +module_tee_client_driver(tpm_qcom_driver); + +MODULE_DESCRIPTION("TPM driver for Qualcomm TPM TA"); +MODULE_AUTHOR("Kuldeep Singh kuldeep.singh@oss.qualcomm.com"); +MODULE_LICENSE("GPL");