How to configure sshd to automatically do port forwarding

[David Bear]

On Wed, Jun 29, 2011 at 7:03 AM, Allen, Jack <Jack.Allen at mckesson.com>wrote:

> -----Original Message-----
> From: redhat-list-bounces at redhat.com [mailto:
> redhat-list-bounces at redhat.com] On Behalf Of Fran Garcia
> Sent: Saturday, June 25, 2011 6:21 PM
> To: General Red Hat Linux discussion list
> Subject: Re: How to configure sshd to automatically do port forwarding
>
> On Thu, Jun 23, 2011 at 23:19, Allen, Jack <Jack.Allen at mckesson.com>
> wrote:
> > Hello:
> >
> >        I have an Application needs to connect to other systems, login
> > run an Application and then transfer data to the other Application. This
> > has been working via a program I wrote years ago called ptsd (Pseudo
> > Terminal Server). Basically the ptsd program listens on a local port
> > (127.0.0.1 20000). The Application open a connection to it and then ptsd
> > prompts for some information and then makes a telnet connection to the
> > other system and then just becomes a pipe, but handling the telnet
> > protocol on one side of it.
>
> You can accomplish this using a config file in the _client_ host, ie:
>
> user at client ~ #  cat .ssh/config
> Host remotehost
> Localforward 20000  localhost:20000
>
> # ssh remotehost
> (connect to port 20000 on clienthost and your connections will be crypted
> :-))
>
> HTH
>
> [Jack Allen] Thanks for the information, but I think you have misunderstood
> my requirement. The Application cannot execute ssh, it must just establish a
> plain TCP connection to a local TCP port and then have a program
> automatically start a ssh connection to the remote system. And user will be
> doing this through the Application and the Application will automatically do
> it at scheduled times. So it needs to look something like this.
>
> Application <-simple-> (Local TCP port, Program or ssh) <-secure-> Remote
> System
>
>
You may want to reconsider this and think about use stunnel. I don't know if
you need to 'authenticate' to the remote host. I sounds more like you just
want to  send bits out a socket to a remote host in a secure way. stunnel
will let you do that without the need to have an account authentication the
way ssh does


-- 
David Bear
College of Public Programs at ASU
602-496-0424