Re: [PATCH v19 17/27] x86/sgx: Add provisioning

[Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>]

On Mon, Mar 25, 2019 at 04:55:03PM +0200, Jarkko Sakkinen wrote:
> > > Hmm.. on 2nd thought the LSM policy or even DAC policy  would restrict
> > > that the container manager can only access specific files inside
> > > securityfs. With this conclusion I still think it is probably the best
> > > place for seurity policy like things even for SGX. It is meant for that
> > > anyway.
> > >
> > 
> > LSM or DAC policy can certainly *restrict* it, but I suspect that most
> > container runtimes don't mount securityfs at all.  OTOH, the runtime
> > definitely needs to have a way to pass /dev/sgx/enclave (or whatever
> > it's called) through, so using another device node will definitely
> > work.
> 
> OK, I can cope with this argument. I go with the device names above for
> v20.

In v20 the refactoring would be with corresponding modes:

/dev/sgx 0755
/dev/sgx/enclave 0666
/dev/sgx/provision 0600

The problem that I'm facing is that with devnode callback of struct
device_type I can easily give the defaut mode for any of the files but
not for the /dev/sgx directory itself. How do I get the appropriate
mode for it?

/Jarkko