On Wed, Dec 20, 2017 at 01:33:46AM +0200, Jarkko Sakkinen wrote: > On Tue, 2017-12-12 at 15:07 +0100, Pavel Machek wrote: > > On Sat 2017-11-25 21:29:17, 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. > > > > Would you list guarantees provided by SGX? > > > > For example, host can still observe timing of cachelines being > > accessed by "protected" app, right? Can it also introduce bit flips? > > > > Pavel > > I'll give a more proper response to this now that all the reported major > issues in the code have been fixed in v9. > > Yes, SGX is vulnerable to the L1 cacheline timing attacks. Jethro > Beekman wrote a great summary about this on early March: > > https://jbeekman.nl/blog/2017/03/sgx-side-channel-attacks/ > > The counter measures are the same as without SGX. It really does not > add or degrade security in this area. This came up even in my patch set :-) I.e. I switched to kernel AES-NI from TinyCrypt's AES because the latter is not timing resistant. /Jarkko
