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0 pointsmonochr10y ago0 comments

>But we also have to acknowledge that we as a profession are not able to write secure code in C/C++.

You can't write safe code in any Turing complete language. That's the whole point of Turing completeness. The only reason why memory attacks are as common as they are is because C like languages are the most popular ones.

If we replaced everything written with C to a "safe" language like, I don't know Haskell?, we'd have just as many zero day exploits of the monads within programs.

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8 comments · 4 top-level

gizmo10y ago· 3 in thread

There is a huge difference between a program that computes the wrong answer and one that corrupts memory, hijacks a shell, and installs a rootkit.

Javascript is turing complete but it's trivial to write a (slow) javascript interpreter in Python that allows anybody to run any javascript program without any risk to their machine. No memory attacks possible. To privilege escalation possible. No unchecked stack overflows. The system would be sandboxed and secure. It will just work or fail gracefully.

It's only when we increase the complexity of our runtimes a thousand fold and when we cut corners to squeeze out higher performance that all the nasty vulnerabilities start to creep in.

sklogic10y ago

It must be really slow in order to avoid attacks like this one: https://github.com/IAIK/rowhammerjs

JoeAltmaier10y ago

For pure Java perhaps. But native code is inevitable, and it has no such protection. So in practice Java is not a lot of protection.

piva0010y ago

I didn't understand how Java relates to his comment about JavaScript + Python.

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sklogic10y ago· 1 in thread

> You can't write safe code in any Turing complete language.

Correct. But, a lot of code is written in Turing complete languages which does not really require any Turing completeness at all. And some code should be implemented in non-Turing-complete, verifiable languages.

iofj10y ago

Of course you can. You can, for instance, include an automatically verified proof that your code terminates for finite inputs.

This is in fact where the newest academic languages are going. In dependantly typed languages bounds checks are only done in theory. you have to include a proof that your indexes are within bounds, and the compiler verifies that proof. If it checks out, it compiles. If not, back you go. Far safer than java/go and the like and far faster than c++. These languages tend to allow pointer arithmetic too, for beating it in speed is almost impossible.

Nelson6910y ago

You cannot write safe code in any Turing complete language? That's a bold assertion that I don't believe is true. Surely you can use formal methods to develop software and maybe even prove it's correctness and security, it's costly in multiple ways but the language of implementation doesn't prevent you from doing this. It is possible to write secure code.

If we replaced everything in C with Haskell, we'd have an entirely different problem. The attack surface wouldn't involve buffer overflows and stack smashing, it would involve various DoS attacks. Those might be easier to address though.

chriswarbo10y ago

> If we replaced everything written with C to a "safe" language like, I don't know Haskell?, we'd have just as many zero day exploits of the monads within programs.

I disagree. There will always be security issues, due to (ab)uses that developers didn't consider, but there can be different probabilities. Requiring developers to learn about language gotchas, remember those gotchas when coding, and jump through hoops to avoid them, just stacks the odds against us.

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