On Thu, Aug 1, 2019 at 9:50 AM Rouven Czerwinski r.czerwinski@pengutronix.de wrote:
I'm aware of it - I have implemented a large part of the GP TEE APIs earlier (primarily the crypto functions). Does the TEE you work with actually support GP properly? Can I take a look at the code?
AFAIK Sumit is working with the OP-TEE implementation, which can be found on github: https://github.com/op-tee/optee_os
Thanks, I will take a look. The fundamental problem with these things is that there are infinite amount of ways how TEEs and ROTs can be done in terms of the hardware and software. I really doubt there are 2 implementations in existence that are even remotely compatible in real life. As such, all things TEE/ROT would logically really belong in the userland and thanks to the bpfilter folks now the umh logic really makes that possible ... I think. The key implementation I did was just an RFC on the concept, what if we start to move the stuff that really belongs in the userspace to this pseudo-userland. It's not kernel, but it's not commonly accessible userland either. The shared memory would also work without any modifications between the umh based TEE/ROT driver and the userland if needed.
Anyway, just my .02c. I guess having any new support in the kernel for new trust sources is good and improvement from the current state. I can certainly make my stuff work with your setup as well, what ever people think is the best.
-- Janne