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[return to "A case against security nihilism"]
1. static+Di[view] [source] 2021-07-20 20:50:05
>>feross+(OP)
Just the other day I suggested using a yubikey, and someone linked me to the Titan sidechannel where researchers demonstrated that, with persistent access, and a dozen hours of work, they could break the guarantees of a Titan chip[0]. They said "an attacker will just steal it". The researchers, on the other hand, stressed how very fundamentally difficult this was to pull off due to very limited attack surface.

This is the sort of absolutism that is so pointless.

At the same time, what's equally frustrating to me is defense without a threat model. "We'll randomize this value so it's harder to guess" without asking who's guessing, how often they can guess, how you'll randomize it, how you'll keep it a secret, etc. "Defense in depth" has become a nonsense term.

The use of memory unsafe languages for parsing untrusted input is just wild. I'm glad that I'm working in a time where I can build all of my parsers and attack surface in Rust and just think way, way less about this.

I'll also link this talk[1], for the millionth time. It's Rob Joyce, chief of the NSA's TAO, talking about how to make NSA's TAO's job harder.

[0] https://arstechnica.com/information-technology/2021/01/hacke...

[1] https://www.youtube.com/watch?v=bDJb8WOJYdA

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2. crater+6q[view] [source] 2021-07-20 21:26:20
>>static+Di
> I'm glad that I'm working in a time where I can build all of my parsers and attack surface in Rust and just think way, way less about this.

I'm beginning to worry that every time Rust is mentioned as a solution for every memory-unsafe operation we're moving towards an irrational exuberance about how much value that safety really has over time. Maybe let's not jump too enthusiastically onto that bandwagon.

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3. ddalci+Xt[view] [source] 2021-07-20 21:48:47
>>crater+6q
What’s with the backlash against Rust? It literally is “just another language”. It’s not the best tool for every job, but it happens to be exceptionally good at this kind of problem. Don’t you think it’s a good thing to use the right tool for the job?
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4. ameliu+8y[view] [source] 2021-07-20 22:21:50
>>ddalci+Xt
It is good to keep in mind that the Rust language still has lots of trade-offs. Security is only one aspect addressed by Rust (another is speed), and hence it is not the most "secure" language.

For example, in garbage collected languages the programmer does not need to think about memory management all the time, and therefore they can think more about security issues. Rust's typesystem, on the other hand, can really get in the way and make code more opaque and more difficult to understand. And this can be problematic even if Rust solves every security bug in the class of (for instance) buffer overflows.

If you want secure, better use a suitable GC'ed language. If you want fast and reasonably secure, then you could use Rust.

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5. tialar+Y11[view] [source] 2021-07-21 03:10:25
>>ameliu+8y
A thing to remember about GC is that it solves only one very important resource. Memory.

If your program loses track of which file handles are open, which database transactions are committed, which network sockets are connected, GC does not help you at all for those resources, when you are low on heap the system automatically looks for some garbage to get rid of, but when you are low on network sockets, the best it could try is hope that cleaning up garbage disconnects some of them for you.

Rust's lifetime tracking doesn't care why we are tracking the lifetime of each object. Maybe it just uses heap memory, but maybe it's a database transaction or a network socket. Either way though, at lifetime expiry it gets dropped, and that's where the resource gets cleaned up.

There are objects where that isn't good enough, but the vast majority of cases, and far more than under a GC, are solved by Rust's Drop trait.

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6. valent+B51[view] [source] 2021-07-21 03:57:11
>>tialar+Y11
It's not like Rust were the only or even the best language in solving the problems you mentioned. It might be the best performance focused / low-level language though.
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