Am Dienstag, 21. Juni 2016, 13:54:13 schrieb Austin S. Hemmelgarn: Hi Austin, > On 2016-06-21 13:23, Stephan Mueller wrote: > > Am Dienstag, 21. Juni 2016, 13:18:33 schrieb Austin S. Hemmelgarn: > > > > Hi Austin, > > > >>> You have to trust the host for anything, not just for the entropy in > >>> timings. This is completely invalid argument unless you can present a > >>> method that one guest can manipulate timings in other guest in such a > >>> way that _removes_ the inherent entropy from the host. > >> > >> When dealing with almost any type 2 hypervisor, it is fully possible for > >> a user other than the one running the hypervisor to manipulate > >> scheduling such that entropy is reduced. This does not imply that the > > > > Please re-read the document: Jitter RNG does not rest on scheduling. > > If you are running inside a VM, your interrupt timings depend on the The RNG does not rest on interrupts either. > hpyervisor's scheduling, period. You may not directly rely on > scheduling from the OS you are running on, but if you are doing anything > timing related in a VM, you are at the mercy of the scheduling used by > the hypervisor and whatever host OS that may be running on. > > In the attack I"m describing, the malicious user is not manipulating the > guest OS's scheduling, they are manipulating the host system's scheduling. Ciao Stephan -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
