On Thu, Apr 30, 2020 at 03:37:08PM +0300, Vesa Jääskeläinen wrote:

TEE Client API defines that from user space only information needed for specified login operations is group identifier for group based logins.

REE kernel is expected to formulate trustworthy client UUID and pass that to TEE environment. REE kernel is required to verify that provided group identifier for group based logins matches calling processes group memberships.

TEE specification only defines that the information passed from REE environment to TEE environment is encoded into on UUID.

In order to guarantee trustworthiness of client UUID user space is not allowed to freely pass client UUID.

Vesa Jääskeläinen (3): tee: add support for session's client UUID generation tee: optee: Add support for session login client UUID generation

I'm picking up these two patches.

[RFC] tee: add support for app id for client UUID generation

I'm waiting with this patch until we've reached some conclusion.

Thanks, Jens

drivers/tee/Kconfig | 1 + drivers/tee/optee/call.c | 6 +- drivers/tee/tee_core.c | 211 +++++++++++++++++++++++++++++++++++++++ include/linux/tee_drv.h | 16 +++ 4 files changed, 233 insertions(+), 1 deletion(-)

-- 2.17.1

Changes v1->v2:

• Changed goto labels to be more logical
• Capture error if formatted string for UUIDv5 does not fit into buffer

Notes:

This patcheset has been designed so that it can be iteratively intergrated meaning that the application ID (RFC patch) part can be left for later when there is agreed solution for that.

TEE specification leaves Linux behavior undefined. It does not define any UUID value for name space. UUID in here is randomly generated with uuidgen tool.

I have also include amdtee people as this method probably should also be applied in there.

Using op-tee@lists.trustedfirmware.org instead of tee-dev@lists.linaro.org as latter is deprecated old list.

Original issue in OP-TEE OS tracker: https://github.com/OP-TEE/optee_os/issues/3642

Related reviews and demonstration for the concept: https://github.com/linaro-swg/linux/pull/74 https://github.com/OP-TEE/optee_client/pull/195 https://github.com/OP-TEE/optee_test/pull/406