SSH tunnel script(2)

I work quite a bit with daemons on remote hosts that are normally not directly listening to the public internet. I use SSH tunnels a lot and had previously used a simplistic script to deal with it.

I got tired of having to reconnect SSH tunnels when I changed environments and wanted autossh to handle the connections. I hacked around a bit with a shell script and then came up with his perl version. The config file is a standard git like config that is quite handy as it handles groups of servers syntax wise.

The calls to tunnel take a tunnel definition from the config file and start the tunnel with the defined user. It is really written for a safe environment and not nailed down for security in the moment but feel free to play with it.

The config file can deal with inheritance and checks the standard directories (/etc, ~/ and .) and looks like this:

[backend "rabbitmq"]
    local  = 5672
    remote = 5672
    host   = RABBIT_HOST
    user   = USER_WITH_SSH_KEYS

[backend "couchdb"]
    local  = 5986
    remote = 5984
    host   = COUCHDB_HOST
    user   = USER_WITH_SSH_KEYS

[frontend "couchdb"]
    local  = 5984
    remote = 5984
    host   = OTHER_COUCHDB_HOST
    user   = USER_WITH_SSH_KEYS

The tunnel script is then called with:

tunnel backend.rabbitmq
tunnel frontend.couchdb
...

It does some basic checking if a port is used already.

The script can be found in my /bin dump on github