On Tue, Jun 19, 2018 at 10:04:15PM +0200, Pavel Machek wrote: > On Tue 2018-06-19 17:59:43, Jarkko Sakkinen wrote: > > On Tue, Jun 12, 2018 at 12:50:12PM +0200, Pavel Machek wrote: > > > On Fri 2018-06-08 19:09:35, Jarkko Sakkinen wrote: > > > > Intel(R) SGX is a set of CPU instructions that can be used by applications > > > > to set aside private regions of code and data. The code outside the enclave > > > > is disallowed to access the memory inside the enclave by the CPU access > > > > control. In a way you can think that SGX provides inverted sandbox. It > > > > protects the application from a malicious host. > > > > > > Do you intend to allow non-root applications to use SGX? > > > > > > What are non-evil uses for SGX? > > > > > > ...because it is quite useful for some kinds of evil: > > > > 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. > What are some non-evil uses for SGX? 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. 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.