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No. The Separation Kernel Protection Profile (SKPP) defines a model for a operating system kernel at EAL6+. So all I am really saying is that safe operating sys
by Veserv 3y ago
No. The Separation Kernel Protection Profile (SKPP) defines a model for a operating system kernel at EAL6+. So all I am really saying is that safe operating systems are safer than non-safe operating systems. You could also look backwards to the TCSEC and the comparable certified Level A1 systems for other operating systems designed for actual high security work.
You keep calling it a farce, but you keep pointing at EAL4 and lower systems. Yes, those levels are farces, that was the whole point. Those are the levels for the certification of toys where documentation and paperwork is all that is needed, not proper design.
Complaining about the Common Criteria in the context of EAL4 and lower systems is like complaining about tissue paper manufacturers putting their tissue paper through bulletproof vest testing and certifying that it does not stop bullets. Yes, that is pretty stupid, farcical, and probably a waste of time. But no, the test is not stupid. It can test actual bulletproof vests, you just keep seeing stupid waste of time tests proving a useless fact that everybody already knows, the EAL4 quality system sucks and has no place in a serious security organization.
- tptacek 3y agoThis is like comparing the L4-based SEPOS to macOS. They share the name "operating system", but they are not the same thing.
- pvg 3y agoI can't help but pick a couple of general points from area standards-arguer man. One is 'problems of standardization in high-development-velocity fields': https://news.ycombinator.com/item?id=3577837 https://news.ycombinator.com/item?id=3577837 The other is "this is worse in security engineering broadly and outright catastrophic in cryptography engineering specifically" https://news.ycombinator.com/item?id=25451351 https://news.ycombinator.com/item?id=25451351 There's probably better/longer, I just looked at the first page of "standards" search. The points are strong, like messageboard-argument-winning bear, though.
- tptacek 3y agoWhat'd I do here? You have me worried. Did I manage to back into an argument that standards processes are good? Really I'm just trying to say two things here: * The Common Criteria process is a farce, and things that are secure by dint of being EAL5+ are really secure because they're so small you can almost prove them with formal methods (which is not to say that everything EAL5+ has usefully applied formal methods). * The meaning of the word "operating system" is different when we're talking about EAL5+ stuff; seL4 is an "operating system" that has been proven secure with formal methods, and it is secure, but it's secure in large part because it does almost nothing; it isn't comparable to Windows, macOS, or Linux. You couldn't build an iPhone experience on top of it (you could --- and people do --- host Unix kernels on top of L4 OS's, but when you do that you keep many/most of the security issues of that Unix kernel).
- pvg 3y agoNo no, sorry, it wasn't intended as backhanded snark. You've had a running critique of standards stuff here for years and it's good and the other person should read it. A bit of an unsuppressed "well, maybe if they looked at the principles, then they'll see the light" nerd-response on my part. You're not going to make an iPhone out of seL4, you're also not going to come up with a Secure Enclave or an IOMMU or an encrypted serial bus or whatever by reading standards/meeting certification reqs either because, generally, that's not how standards and certifications work. For multiple developed versions of this argument, see 'tptacek! I'm sure you're right about the details of Jor-EAL5+ and the bottle city CRYSTALS-Kandor, just saying "also right in this other way but with less lore". Not that there is anything wrong with lore.
- tptacek 3y agoWell, you'll make the iPhone fingerprint reader out of seL4. :)
- Veserv 3y agoSo what you are saying is that EAL >=5 does not imply secure, it is the formal methods that imply secure? Well good news, that is not a mistake. EAL >=5 implies formal methods of various degrees. The standard demands the thing that works, amazing. It might be too hard for consumer companies to achieve, but that does not make the process a farce as long as there are companies that can certify useful functionality according to the process. And, although you seem to think the functionality that can be certified is limited, I doubt you consider secure cryptographic co-processors useless or unimportant.