[sslh] Port Knocking for SSLH

[Kai]

Hello all,

I guess it is not implemented but I have the following question of a 
feature that might be interesting to implement:

There is something called Port Knocking where I can for example access 
the SSH port after I knocked on another port before.

My question is now whether and how it would be possible to implement 
this in SSLH.

For example if I call something like an specific secret URL and than I 
am able to be forwarded to the SSH port for the next 10 seconds.

I know that SSLH is not able to terminate SSL and must forward it to - 
for example - Apache. But on Apache, I could for example run a CGI 
script that notifies in any way SSLH and tell "please open SSHd 
forwarding for 10 minutes".

So from that point of view we need a way to request SSHd port forwarding 
by a process running on the same machine than SSLH and automatically 
close it after a configured time.

Thanks a lot for your feedback.

/Kai