Question on Netcat and Port Forwarding

[Patrick Rynhart]

Question on Netcat and Port Forwarding

I want to set up a port forward, so that port 1000 is forwarded (via
'server') to port 2000 on 'mycomputer'. If 'server' was running sshd,
I would use the command

ssh server -L 1000:mycomputer:2000

However, server does not have sshd installed. Is it possible to
acheive this requirement by running netcat on server at user-level ?

If so, how would this be acheived ?

Regards

Patrick

[Kasper Dupont]

Patrick Rynhart wrote:
>
> Question on Netcat and Port Forwarding
>
> I want to set up a port forward, so that port 1000 is forwarded (via
> 'server') to port 2000 on 'mycomputer'. If 'server' was running sshd,
> I would use the command
>
> ssh server -L 1000:mycomputer:2000
>
> However, server does not have sshd installed. Is it possible to
> acheive this requirement by running netcat on server at user-level ?

How did you plan to get the connection from the client
to server?

Maybe you can do something with nc and the -e option.
Something like listening on one port and starting an
instance of nc when receiving a connection. But I
couldn't test it, because some paranoid person
decided -e should be disabled.

Anyway I recently wrote a program to do something
very similar. You can see the source here:
http://www.daimi.au.dk/~kasperd/linux_kernel/wrapper.c

--
Kasper Dupont -- der bruger for meget tid paa usenet.
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