Accessing hidden camera

wgcampbell · 01-13-2009, 09:19 PM

I have a small network behind a wireless router that I don't control. I pick up the signal with my own wireless router, then run a small internal network from my wireless router (including a linux box and a wireless web camera). I would like to view (browse to) the web cam from the outside.

I was thinking of setting up a reverse ssh tunnel from the linux box on the internal network to another linux box at my office (which would act as my "outside" access). This would let me get into the network (to my linux box) from the outside but then I somehow need to redirect that connection to the camera (web server).

Suggestions would be appreciated.

blackhole54 · 01-14-2009, 01:45 AM

Hi,

Welcome to LQ!

Would

Code:

ssh -N -R remoteport:wcserver:wcport username@remotehost

work?

I am designating your ("outside") office as remotehost where sshd will be listening for connections on remoteport. Likewise wcserver is the machine hosting the webcam on wcport. (If the ssh connection is originating from the machine with the webcam, then use "localhost" or 127.0.0.1 for wcserver.)

wgcampbell · 01-14-2009, 04:34 PM

Actually there is no machine hosting the webcam - it is a stand alone wireless camera with a web server interface. Your reverse SSH tunnel works, but I then need some way to then redirect the port 80 requests coming in over to the webcam??

hvc123 · 01-14-2009, 05:53 PM

its ugly but cant u open another ssh port redirect in another terminal to port 80

wgcampbell · 01-14-2009, 09:22 PM

I'm not quite sure how to do what you're suggesting: "open another ssh port redirect in another terminal to port 80"

Somehow I need to extend the reverse ssh connection to the web cam??

blackhole54 · 01-15-2009, 08:16 AM

Quote:

Originally Posted by wgcampbell

but I then need some way to then redirect the port 80 requests coming in over to the webcam??

I'm not sure I understand. Using the terminology in post #2, wcserver would be the IP address of your webcam and wcport would be the port it listens on (port 80?).

Are you talking about getting requests on what I called remotehost to remoteport? I would think you could REDIRECT with iptables for that. You might have to use bind_address as explained in ssh's man page:

Code:

      -R [bind_address:]port:host:hostport
             Specifies that the given port on the remote (server) host is to
             be forwarded to the given host and port on the local side.  This
             works by allocating a socket to listen to port on the remote
             side, and whenever a connection is made to this port, the connec-
             tion is forwarded over the secure channel, and a connection is
             made to host port hostport from the local machine.

             Port forwardings can also be specified in the configuration file.
             Privileged ports can be forwarded only when logging in as root on
             the remote machine.  IPv6 addresses can be specified by enclosing
             the address in square braces or using an alternative syntax:
             [bind_address/]host/port/hostport.

             By default, the listening socket on the server will be bound to
             the loopback interface only.  This may be overriden by specifying
             a bind_address.  An empty bind_address, or the address '*', indi-
             cates that the remote socket should listen on all interfaces.
             Specifying a remote bind_address will only succeed if the
             server's GatewayPorts option is enabled (see sshd_config(5)).

wgcampbell · 01-15-2009, 11:31 PM

After tinkering with reverse tunnel ssh and iptables, I discovered that the whole thing could be accomplished with remote tunnel ssh using a "bind_address". The final solution was:

Code:

$ ssh -R [Offsite SSH Server IP]:[Offsite Accepted Port]:[Internal webcam IP]:[Webcam Port] [Offsite URL]

You must have GatewayPorts set to "yes" (in your sshd.config file) in order to effectively utilize this solution. Thanks much for all of the suggestions.