Re: [PATCH v36 15/24] x86/sgx: Allow a limited use of ATTRIBUTE.PROVISIONKEY for attestation

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

On Thu, Aug 06, 2020 at 06:00:02PM +0100, Darren Kenny wrote:
> On Thursday, 2020-07-16 at 16:52:54 +03, Jarkko Sakkinen wrote:
> > Provisioning Certification Enclave (PCE), the root of trust for other
> > enclaves, generates a signing key from a fused key called Provisioning
> > Certification Key. PCE can then use this key to certify an attestation key
> > of a Quoting Enclave (QE), e.g. we get the chain of trust down to the
> > hardware if the Intel signed PCE is used.
> >
> > To use the needed keys, ATTRIBUTE.PROVISIONKEY is required but should be
> > only allowed for those who actually need it so that only the trusted
> > parties can certify QE's.
> >
> > Obviously the attestation service should know the public key of the used
> > PCE and that way detect illegit attestation, but whitelisting the legit
> > users still adds an additional layer of defence.
> >
> > Add new device file called /dev/sgx/provision. The sole purpose of this
> > file is to provide file descriptors that act as privilege tokens to allow
> > to build enclaves with ATTRIBUTE.PROVISIONKEY set. A new ioctl called
> > SGX_IOC_ENCLAVE_SET_ATTRIBUTE is used to assign this token to an enclave.
> >
> > Cc: linux-security-module@vger.kernel.org
> > Acked-by: Jethro Beekman <jethro@fortanix.com>
> > Suggested-by: Andy Lutomirski <luto@kernel.org>
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> 
> Reviewed-by: Darren Kenny <darren.kenny@oracle.com>

Thanks, I added your tags to the corresponding commits.

/Jarkko