This patch series introduces a Trusted Execution Environment (TEE) driver for Qualcomm TEE (QTEE). QTEE enables Trusted Applications (TAs) and services to run securely. It uses an object-based interface, where each service is an object with sets of operations. Clients can invoke these operations on objects, which can generate results, including other objects. For example, an object can load a TA and return another object that represents the loaded TA, allowing access to its services.
Kernel and userspace services are also available to QTEE through a similar approach. QTEE makes callback requests that are converted into object invocations. These objects can represent services within the kernel or userspace process.
Note: This patch series focuses on QTEE objects and userspace services.
Linux already provides a TEE subsystem, which is described in [1]. The tee subsystem provides a generic ioctl interface, TEE_IOC_INVOKE, which can be used by userspace to talk to a TEE backend driver. We extend the Linux TEE subsystem to understand object parameters and an ioctl call so client can invoke objects in QTEE:
- TEE_IOCTL_PARAM_ATTR_TYPE_OBJREF_* - TEE_IOC_OBJECT_INVOKE
The existing ioctl calls TEE_IOC_SUPPL_RECV and TEE_IOC_SUPPL_SEND are used for invoking services in the userspace process by QTEE.
The TEE backend driver uses the QTEE Transport Message to communicate with QTEE. Interactions through the object INVOKE interface are translated into QTEE messages. Likewise, object invocations from QTEE for userspace objects are converted into SEND/RECV ioctl calls to supplicants.
The details of QTEE Transport Message to communicate with QTEE is available in [PATCH 10/10] Documentation: tee: Add Qualcomm TEE driver.
You can run basic tests with following steps: git clone https://github.com/quic/quic-teec.git cd quic-teec mkdir build cmake .. -DCMAKE_TOOLCHAIN_FILE=CMakeToolchain.txt -DBUILD_UNITTEST=ON
https://github.com/quic/quic-teec/blob/main/README.md lists dependancies needed to build the above.
This series has been tested for basic QTEE object invocations and callback requests, including loading a TA and requesting services form the TA.
[1] https://www.kernel.org/doc/Documentation/tee.txt
Signed-off-by: Amirreza Zarrabi quic_azarrabi@quicinc.com --- Changes in v2: - Clean up commit messages and comments. - Use better names such as ubuf instead of membuf or QCOMTEE prefix instead of QCOM_TEE, or names that are more consistent with other TEE-backend drivers such as qcomtee_context_data instead of qcom_tee_context. - Drop the DTS patch and instantiate the device from the scm driver. - Use a single structure for all driver's internal states. - Drop srcu primitives and use the existing mutex for synchronization between the supplicant and QTEE. - Directly use tee_context to track the lifetime of qcomtee_context_data. - Add close_context() to be called when the user closes the tee_context. - Link to v1: https://lore.kernel.org/r/20241202-qcom-tee-using-tee-ss-without-mem-obj-v1-...
Changes in v1: - It is a complete rewrite to utilize the TEE subsystem. - Link to RFC: https://lore.kernel.org/all/20240702-qcom-tee-object-and-ioctls-v1-0-633c3dd...
--- Amirreza Zarrabi (8): tee: allow a driver to allocate a tee_device without a pool tee: add close_context to TEE driver operation tee: add TEE_IOCTL_PARAM_ATTR_TYPE_UBUF tee: add TEE_IOCTL_PARAM_ATTR_TYPE_OBJREF firmware: qcom: scm: add support for object invocation tee: add Qualcomm TEE driver qcomtee: add primordial object Documentation: tee: Add Qualcomm TEE driver
Documentation/tee/index.rst | 1 + Documentation/tee/qtee.rst | 150 ++++++ drivers/firmware/qcom/qcom_scm.c | 128 ++++++ drivers/firmware/qcom/qcom_scm.h | 7 + drivers/tee/Kconfig | 1 + drivers/tee/Makefile | 1 + drivers/tee/qcomtee/Kconfig | 10 + drivers/tee/qcomtee/Makefile | 10 + drivers/tee/qcomtee/async.c | 160 +++++++ drivers/tee/qcomtee/call.c | 741 ++++++++++++++++++++++++++++++ drivers/tee/qcomtee/core.c | 810 +++++++++++++++++++++++++++++++++ drivers/tee/qcomtee/primordial_obj.c | 65 +++ drivers/tee/qcomtee/qcom_scm.c | 36 ++ drivers/tee/qcomtee/qcomtee_msg.h | 234 ++++++++++ drivers/tee/qcomtee/qcomtee_private.h | 226 +++++++++ drivers/tee/qcomtee/release.c | 59 +++ drivers/tee/qcomtee/shm.c | 102 +++++ drivers/tee/qcomtee/user_obj.c | 712 +++++++++++++++++++++++++++++ drivers/tee/tee_core.c | 121 ++++- drivers/tee/tee_private.h | 6 - include/linux/firmware/qcom/qcom_scm.h | 27 ++ include/linux/firmware/qcom/qcom_tee.h | 286 ++++++++++++ include/linux/tee_core.h | 15 +- include/linux/tee_drv.h | 18 + include/uapi/linux/tee.h | 54 ++- 25 files changed, 3964 insertions(+), 16 deletions(-) --- base-commit: dab2734f8e9ecba609d66d1dd087a392a7774c04 change-id: 20241202-qcom-tee-using-tee-ss-without-mem-obj-362c66340527
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