Re: [PATCH v11 00/13] Intel SGX1 support

[Josh Triplett]

On Sun, Dec 09, 2018 at 09:06:00PM +0100, Pavel Machek wrote:
...
> > > > The default permissions for the device are 600.
> > > 
> > > Good. This does not belong to non-root.
> > 
> > There are entirely legitimate use cases for using this as an
> > unprivileged user. However, that'll be up to system and distribution
> > policy, which can evolve over time, and it makes sense for the *initial*
> > kernel permission to start out root-only and then adjust permissions via
> > udev.
> 
> Agreed.
> 
> > Building a software certificate store. Hardening key-agent software like
> > ssh-agent or gpg-agent. Building a challenge-response authentication
> > system. Providing more assurance that your server infrastructure is
> > uncompromised. Offloading computation to a system without having to
> > fully trust that system.
> 
> I think you can do the crypto stuff... as crypto already verifies the
> results. But I don't think you can do the computation offload.

You can, as long as you can do attestation.

> > As one of many possibilities, imagine a distcc that didn't have to trust
> > the compile nodes. The compile nodes could fail to return results at
> > all, but they couldn't alter the results.
> 
> distcc on untrusted nodes ... oh yes, that would be great.
> 
> Except that you can't do it, right? :-).
> 
> First, AFAICT it would be quite hard to get gcc to run under SGX. But
> maybe you have spare month or three and can do it.

Assuming you don't need to #include files, gcc seems quite simple to run
in an enclave: data in, computation inside, data out.