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Hypothetical, but would intel be better off trying to allocate one of its 70 cores as a dedicated crypto processor with dedicated memory rather than fall down the trap of trying to safely share resources?
Earlier quoted context omitted.
The assumption behind PoET is precisely that you don't control a part of your machine (the SGX enclave). I agree that that's an unreasonable assumption which is why we developed RRR.
> I agree that that's an unreasonable assumption which is why we developed RRR. Out of curiosity, I would've hoped that the consensus in the cryptography community is that "secure enclaves" are pretty much snake oil to begin with... is this not the case? (I mean... for a secure enclave to actually work, you need "perfect" physical security, "perfect" software implementation inside, and "perfect" design of the cryptog…
TL;DR: same as ARM's Trustzone ... brilliant for hiding malware.
ARM TrustZone is predicated on the Secure World being potentially able to monitor and modify the entire Non-Secure World, because it has control over the MMU (see TZASC, TZMA, TZPC). The reverse is clearly impossible.
SGX instead is defined as a "secure" sandbox, it has basically no privilege even over the process it runs in.
Having said that, researches demonstrated examples of SGX-based malware, which is ultimately rooted in the fact that SGX state is not fully observable (i.e. you can load encrypted code, though you need a lot scaffolding). However, such malware uses a lot of tricks whose side effects can be detected (notwithstanding the fundamental microarchs attacks).
TL;DR: same as ARM's Trustzone ... brilliant for hiding malware.
From a paper in that article: "Intel has recently added support for monotonic counters [5] as an optional SGX feature that an enclave developer may use for rollback attack pro- tection, when available. However, the security and per- formance properties of this mechanism are not precisely documented. We performed a detailed analysis of SGX counters and report our findings in Appendix B. To summarize, we found out that…
From a paper in that article: "Intel has recently added support for monotonic counters [5] as an optional SGX feature that an enclave developer may use for rollback attack pro- tection, when available. However, the security and per- formance properties of this mechanism are not precisely documented. We performed a detailed analysis of SGX counters and report our findings in Appendix B. To summarize, we found out that…
How long until we see an SGX-damaging malware in the wild that simply eats up all the monotonic counters?
TL;DR: same as ARM's Trustzone ... brilliant for hiding malware.
I disagree. ARM TrustZone is predicated on the Secure World being potentially able to monitor and modify the entire Non-Secure World, because it has control over the MMU (see TZASC, TZMA, TZPC). The reverse is clearly impossible. SGX instead is defined as a "secure" sandbox, it has basically no privilege even over the process it runs in. Having said that, researches demonstrated examples of SGX-based malware, which i…
precisely for this reason ... that it raises the cost of an attacker by also raising the cost for security researchers and making introspection impossible, ... it is snake-oil. It's a perfect hiding spot not despite but because of this!
So the security of a blockchain now depends on the security of the SGX enclave? What could possibly go wrong... > Unfortunately, this proposal suffers from a critical security economics issue: node maintainers here have a strong incentive to break into their own SGX chips. If an adversary managed to compromise their SGX, they could win the leader election at every round by setting the timeout to 0. The more valuable…
Peer-to-peer computation is hard to implement because of the quite hairy social aspect of requiring a trust root that is out of direct control of the owner of the equipment.
Earlier quoted context omitted.
How long until we see an SGX-damaging malware in the wild that simply eats up all the monotonic counters?
Or ransomware that does so if the ransom is not paid. This can also be done with UEFI variable writes, since the flash where they are stored is... often not of the highest quality!