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Comment by cogman10 | Hacker News Reader

If you can bring in 3rd party libraries, you can be hit with a supply chain attack. C and C++ aren't immune, it's just harder to pull off due to dependency management being more complex (meaning you'll work with less dependencies naturally).

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It's not more complex in C or C++, you just have less of a culture of buying into a whole eco-system. C and C++ play nice with the build system that you bring, rather than that you are forced into a particular way of working.

It's 'just a compiler' (ok, a bit more than that). I don't need to use a particular IDE, a particular build system, a particular package manager or even a particular repository.

That is not to throw shade on those other languages, each to their own, but I just like my tools to stay in their lane.

Just like I have a drawer full of different hammers rather than one hammer with 12 different heads, a screwdriver, a hardware store and a drill attachment. I wouldn't know what to do with it.

You’ll find more quality libraries in C because people don’t care about splitting them down to microscopic parcels. Even something like ‘just’ have tens of deps, including one to check that something is executable.

https://github.com/casey/just/blob/master/Cargo.toml

That’s just asking for trouble down the line.

yes, the average amount of dependencies used per dependency appears to be much larger in rust and thats what I meant and is worrying me. In theory C can be written in a memory safe manner, and in theory rust can be used without large junks of supply vulnerabilities. both of these are not the case in practice though

One difference is that it's an incredibly hard problem to check whether your C code is memory safe since every single line of your code is a risk. On the other hand, it's easy to at least assess where your supply vulnerabilities lie (read Cargo.toml), and you can enforce your policy of choice (e.g. whitelist a few specific dependencies only, vendor them, etc).

I would argue that almost all major rust projects use dependencies. Checking the dependencies for vulnerabilities might be just as difficult as checking C code for memory safety, maybe even worse, because dependencies have dependencies and the amount of code to be checked can easily sky rocket. The problem gets even worse if you consider that not all rust code is safe, and that C libraries can be included and so on

Yes, but I believe that results in a cost/benefit analysis. If there are readily available rust crates that do something you need, and the cost of a possible vulnerability is not huge, most projects might decide (right or wrong) that it is worth it. It's an interesting question why projects tend to make different decisions in different languages, but it does not necessarily mean that you have to make the same decisions.

My point is that if you put a very high emphasis on avoiding vulnerabilities, you can either write the code in C with no/limited dependencies (and still risk memory safety bugs), or write the code in Rust with no/limited dependencies and no/limited unsafe code, and get much stronger guarantees for the same/less effort.

Fair, you see the perspective from someone writing the software and it makes sense. But when I see it though the lenses of someone choosing software to run, I would rather choose a C program with potential memory bugs than a rust program with a lot of dependencies - because I am more scared about supply chain attacks than someone being able to exploit a memory bug. But then again, this obviously changes if the rust program has no dependencies.

> both of these are not the case in practice though

No, people routinely write Rust with no third-party dependencies, and yet people do not routinely write C code that is memory-safe. Your threat model needs re-evaluating. Also keep in mind that the most common dependencies (rand, serde, regex, etc) are literally provided by the Rust project itself, and are no more susceptible to supply chain attacks than the compiler.

I know it's a sensitive topic for a lot of people, but as I said, I love rust. I don't know a lot of rust projects though that don't use any dependencies. In my humble opinion, disregarding the risks of such supply chain attacks is at least as bad as people disregarding the risk of memory unsafe code. But keep in mind, I'm not saying don't use rust.

mamma mia! one day anyhow and anyerror will be backdoored it's inevitable

People also write Rust code that is not memory-safe.

https://materialize.com/blog/rust-concurrency-bug-unbounded-...

But not "routinely".

How can you be sure? When I looked at for instance sudo-rs, it proclaimed loudly that it is memory safe, but its code has lots of unsafe.

https://github.com/trifectatechfoundation/sudo-rs

https://grep.app/search?f.repo=trifectatechfoundation%2Fsudo...

And Miri is very popular in Rust. Even if a Rust project doesn't have unsafe, sometimes people still run Miri with it, since dependencies might have messed up their unsafe usage.

> but its code has lots of unsafe.

And every instance of unsafe that I could find (except one, in test-only code) was a call to libc with a clarifying comment on why this particular use was safe. That is, all (or at least, all of it that I could find) was wrapping an unsafe API with documented (and usually straightforward and local) invariants that maintain safety, such that the calling code is safe.

I'd say that the fact that miri's trophy-shelf[0] has 39 entries and is 7 years old and still regularly updated is a pretty good indicator that memory bugs are sufficiently rare in rust so as to be notable. That is the opposite of "regular"

[0]: https://github.com/rust-lang/miri/blame/master/README.md

The vast majority of Rust code out there doesn't use the `unsafe` keyword at all, and the vastly smaller amount of unsafe code that exists allows for focused and precise testing and verification. You really have no idea what you're talking about if you're trying to say that Rust is anywhere in the ballpark of C or C++ here.

Indeed, unsafe Rust is overall more difficult than C++, like one speaker at a Rust conference claimed: https://lucumr.pocoo.org/2022/1/30/unsafe-rust/

And you are not being honest nor accurate here.

You also won’t typically find C/C++ developers blinding yolo’ing the latest version of a dependency from the Internet into their CI/CD pipeline.

They’ll stick with a stable version that has the features they need until they have a good reason to move. That version will be one they’ve decided to ship themselves, or it’ll be provided by someone like Debian or Red Hat.

Unless of course they are using vcpkg, conan or FetchContent.

Most corporations are already using the likes of Nexus or JFrog Artifactory, regardless of the programming language.

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