Re: Avoiding tunnels

[Neil <neil () voidfx net>]

Javier Hijas wrote:
> Hi all,
>   I wonder if there is a way to avoid tunnels via fw (v.g. netfilter).
> How can I control that an opened port 80 is not used to tunel to a ssh
> server listening at port 80?
>
> Thanks

I think if you tell the firewall only to accept HTTP on port 80, that'll
do the trick (requires stateful inspecting firewall).

Don't think it'll work on HTTPS, because HTTPS is encrypted anyways, so
then you'd need a firewall doing a MITM to inspect it, otherwise it just
passes the encrypted traffic onwards.

--
Neil.
http://voidfx.net
"...the student skit at Christmas contained a plaintive line: "Give us
Master's exams that our faculty can pass, or give us a faculty that can
pass our Master's exams."
--Paul R. Halmos

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