glibc errors and `CGO_ENABLED`

[exploide]

First of all let me thank you for this ridiculously awesome reverse shell. 😄 It's so useful!

But I discovered a problem after transferring the client to another machine and running it:

$ ./rssh -h
./rssh: /lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.32' not found (required by ./rssh)
./rssh: /lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.34' not found (required by ./rssh)

This is because the glibc version on my build machine is another than the glibc version available on the target. I'm not a Go programmer and was a bit confused, why C and isn't it supposed to be a single static binary?

I found an answer then and CGO_ENABLED=0 make client produces a perfectly functioning client, statically compiled, without C dependencies.

I think it is crucial for the reverse_ssh client to be compatible with environments you don't control. So I would like to propose adding CGO_ENABLED=0 to the Makefile (or at least document it for people not familiar with Go internals).

I don't know if this has any drawbacks. I expected the client to be larger in size, but actually it is smaller than the client linked to glibc.

[NHAS]

Hi there!

Thanks for your issue and corresponding pull request!
I think this is a good addition, my previous thought process was that people would specify CGO_ENABLED themselves, and that some built types need it (see shared library).

But its more sensible to have a compatible default