Tunnel netbios over ssh

[John Trunek]

I need to be able to tunnel netbios traffic over ssh to browse to a
windows share and get through restrictions that my isp put in place. I
know a true vpn solution would be more elegant, but I don't have access
to the server on the destination network to set up a vpn server.

I know that I need to tunnel port 139/tcp. This tunnel works fine if i
just use telnet to test the tunnel. However, when I try accessing the
shares is when I run into problems. Anyone able to explain what I'm
doing wrong?

 

[allan grossman [mvp]]

Hi, John -

You've got one end of the tunnel set up - but what about
the other end? Since the remote network isn't expecting
to see NetBIOS over SSH it's still listening on standard
NetBIOS ports.

Out of the box SSH talks on port 22 - you need to get the
remote machine to talk on port 22 as well.

Your ISP's firewall doesn't care if the traffic is
encrypted or not - the bottom line is they're blocking
all traffic on NetBIOS ports. If your ISP blocks NetBIOS
traffic and if you're able to tunnel to the remote
machine you can't be doing it on a standard NetBIOS port -
so something has to tell the remote machine where to
look for traffic. Sending NetBIOS requests on port 22
won't do much because the remote machine doesn't know to
listen on port 22 for that stuff ;-)

I'm afraid a VPN or a new ISP might be the only way to
solve this.

Sorry I didn't have better news -

 

[John Trunek]

Hi, John -

You've got one end of the tunnel set up - but what about
the other end? Since the remote network isn't expecting
to see NetBIOS over SSH it's still listening on standard
NetBIOS ports.

Out of the box SSH talks on port 22 - you need to get the
remote machine to talk on port 22 as well.

Your ISP's firewall doesn't care if the traffic is
encrypted or not - the bottom line is they're blocking
all traffic on NetBIOS ports. If your ISP blocks NetBIOS
traffic and if you're able to tunnel to the remote
machine you can't be doing it on a standard NetBIOS port -
so something has to tell the remote machine where to
look for traffic. Sending NetBIOS requests on port 22
won't do much because the remote machine doesn't know to
listen on port 22 for that stuff ;-)

I'm afraid a VPN or a new ISP might be the only way to
solve this.

Sorry I didn't have better news -

I should have clarified. The SSH server is just the endpoint for the
tunnel and acts as a proxy forwarding the NetBIOS traffic to the
appropriate server. Or at least thats what I think I'm trying to do.

windows xp client --------> ssh server ----------> destination server
listens on port 22 listens on port 139
forward to port 139