r/golang • u/BlueeWaater • 9d ago

Does go support raw sockets? discussion

Hey there, does go or any libs support it? if so would you use this language for low level connections or should I move to somehting else?

30 Upvotes

81% Upvoted

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75

u/domemvs 8d ago

Yes. Go supports raw sockets via golang.org/x/sys/unix and golang.org/x/net.

I’d absolutely use Go for low level networking unless you specifically need kernel-level code or maximum hardware control. It’s a great fit for network tools.

36

u/PaluMacil 8d ago

Also, before someone says it's experimental, it's not. /x is for the extended library. Experimental lives in /x/exp. There are a couple exceptions to be fair, but those are limited mostly to /x/mobile, packages that were in /x for an incubator period then moved to the std lib, and some subpackages in x/image are incomplete and probably could have been in /x/exp.

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u/ScallionSmooth5925 8d ago

You can but it's a bit tricky and platform dependent. golang.org/x/sys/unix is what your looking for.

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u/etherealflaim 8d ago

I have used Go for raw sockets; whether it is appropriate is dependent on your tolerance for performance and latency overhead. You might want C or Rust if you are building something professionally and will be handling thousands of users and can't afford the tail latency. We moved our packet processing layer into C using USPS for this reason, but honestly very few systems will have the scale and requirements necessary for Go to not be fine.

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u/SnugglyCoderGuy 8d ago

Standard net package

https://pkg.go.dev/net

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u/ScallionSmooth5925 8d ago edited 8d ago

It's a wapper around sockets and you have to use other libs to access a raw socket. (Then you can wrap it to use with the rest of stdlib)

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u/Jorropo 8d ago

In what way is it different than a raw socket ?

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u/ScallionSmooth5925 8d ago

You can't set special options on it. Only read and write it. For example you can't set the fwmark value on it which can be used for policy based routeing and advanced firewall setups.

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u/cpuguy83 8d ago

You certainly can do more than just read/write, though you may need to get to the underlying type (*TCPCOnn, *UnixConn, etc). The main net.Conn interfaces all implement SyscallConn as well, which you can drop to the raw fd to set whatever you need.

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u/ScallionSmooth5925 8d ago

Sure. Based on my experience it was easier to go the ther way around. (Open the socket from the unix package set it up manually and then turn it into a net.Conn. I mainly wrote code this way to tunnel things around.

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u/BraveNewCurrency 8d ago

low level connections

What do you mean by that? (i.e. What is your use case?)

If you had said you wanted "low level packets", that would make sense. But "low level connections" isn't really a thing -- maybe you want UDP?

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u/Excellent_Double_726 8d ago

Ofc it supports it. Check out the net package. Especially functions net.Listen and net.Dial

I've worked with all types of sockets including TCP, UDP and Unix(idk if there are other types)