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by saagarjha 1063 days ago
Those seem to be of the category of “I have a program and I want to restrict what it does” which seems like a sandbox to me. The problem here is that trying to figure out what goes on this list is difficult for arbitrary programs, even when you’re the one writing it. When you’re just applying it to third party software it’s very likely something will not function correctly.
1 comments
PrimeMcFly 1063 days ago
It's not a sandbox though, because it's a different type of technology. You can say it's a type of sandbox in concept, and you could make an argument, but referring to it as a sandbox in a technical discussion simply isn't correct.

> The problem here is that trying to figure out what goes on this list is difficult for arbitrary programs, even when you’re the one writing it. When you’re just applying it to third party software it’s very likely something will not function correctly.

That's why there are things like, for example, SELinux permissive mode, where you run the software as needed and observe the permissions it needs, and then grant it those permissions while denying everything else.

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saagarjha 1062 days ago
I mean the typical term used for such things is “mandatory access control” but they always get used to implement a sandbox so that’s what I call them.

Also, watching a program to see what it does is exactly the issue I’m talking about. You’re stuck with whatever behaviors you tested and everything else that you didn’t hit will fail (loudly if you’re lucky, silently if you’re not). There are platforms that do exactly what you’re talking about and believe me working on these rules is miserable. You’ll have reports on your desk like “the profiler doesn’t work anymore” (nobody tested this) or “on desktop controls don’t render anymore” (someone changed the implementation and it needs something you didn’t include in your rules). Again, this is when you control the stack, doing this for arbitrary programs is an order of magnitude harder.

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PrimeMcFly 1062 days ago
Some implement role based access control or other access control paradigms as well. I just don't think sandbox is a good term, but I see where you're coming from.

I agree initial setup can be cumbersome, but I think it's worthwhile. I'm a fan of RSBAC personally, it's as powerful as SELinux but a lot simpler. If people run in permissive mode and test properly, not just run it and do a few things, but test every function exhaustively before setting up permissions, it should be good.

Really, it only has to be done once, and I think it's a worthwhile investment given the security gained.

That's what I was saying higher up in the thread though. OpenBSD is known for having good, simple implementations of complex stuff like this, so if they ever were itnerested in implementing a version, it would probably be amazing.

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