TCP-Switch Application

The TCP-Switch Application allows tunneling HTTP, HTTPS, HTTPS-Proxy, passive FTP and SSH request on one port to different hosts and ports.
This can be usefull if there are limited port numbers because of a firewall.
Tunnels can be configured depending on the client IP and port, the current date and time.
The project has just started and is at the very beginning. So there is not much documentation and not everything is perfect.

Copy the file tcpswitch.jar and tcpswitch.config to any location. Edit tcpswitch.config to match your needs. The application is started with

  java -jar tcpswitch.jar

  java -jar tcpswitch [-config=<configfile>] 
                      [-daemon] [-loghostname] [-debug]
    -config: use <configfile> instead of "./tcpswitch.config"  
    -daemon: do not enter interactive mode
    -loghostname: log hostname in addition to ip address
    -debug:  verbose logging

The configfile is named tcpswitch.config and has to be in the current working directory. An other config file my be used with the -config=... option

An simple example config:

[--- tcpswitch.config ---]
listen (8555) {
    forward sf.net:80
}
[------------------------]

[--- tcpswitch.config ---]
listen (8555) {
    forward sf.net:80
}
listen (8556) {
    forward localhost:8555
}
[------------------------]

[--- tcpswitch.config ---]
listen (8555) {
    check ($ip = 127.0.0.1) {
        forward sf.net:80
    }
    check ($ip >= 10.10.10.0) {
        check ($ip <= 10.10.10.255) {
            forward fsf.net:80
        }
    }
    check ($port < 1024) {
        reject
    }
    forward gnu.org:80
}
[------------------------]

[--- tcpswitch.config ---]
listen (8555) {
    check ($date = 2004-02-29) {
        reject
    }
    check ($time < 08:00:00) {
        reject
    }
    check ($time < 18:00:00) {
        forward sf.net:80
    }
    /* time >= 18:00:00 */
    reject
}
[------------------------]

[--- tcpswitch.config ---]
listen (443) {
    check ($protocol = HTTP) {
        check ($time < 12:00:00) {
            forward www.gnu.org:80,HTTPrewritehost
        }
        /* $time >= 12:00:00 */
        forward www.fsf.org:80,HTTPrewritehost
    }
    check ($protocol = HTTPS) {
        forward sourceforge.net:443
    }
    check ($protocol = HTTPSPROXY) {
        forward $proxyhost:$proxyport,HTTPSPROXYestablish
    }
    check ($protocol = FTP) {
        forward ftp.debian.org:21
    }
    check ($protocol = SSH) {
        forward localhost:22
    }
    reject
}
[------------------------]

Use the last config file above.
On the command line (unix or dos) enter the following

  java -jar tcpswitch.jar

  URL: http://localhost:443/

  URL: https://localhost/

  ftp -p localhost 443

  ssh -p 443 localhost

With the HTTPSPROXY protocol some useful things can be done.
Assume the following scenario:

[--- localhost-config ---]
listen (9122) {
    forward public.net:443,HTTPSPROXYconnect(intrahost1:22)
}
listen (9222) {
    forward public.net:443,HTTPSPROXYconnect(intrahost2:22)
}
[-------------------------]

[--- public.net-config ---]
listen (443) {
    check ($protocol = HTTPSPROXY) {
        forward $proxyhost:$proxyport,HTTPSPROXYestablish
    }
    forward wwwhost:443
}
[------------------------]

[--- public.net-config ---]
listen (443) {
    check ($protocol = HTTPSPROXY) {
        check ($proxyhost = intrahost1) {
            forward intrahost1:22
        }
        check ($proxyhost = intrahost2) {
            forward intrahost1:22
        }
        reject
    }
    forward wwwhost:443
}
[------------------------]

• HTTPSPROXY should support also HTTP Proxying
• loadbalancing, e.g. forward host1:21+host2:21,LBsticky
• bandwith limitation, e.g. forward host1:21,maxspeed=64k
• other protocols

Only HTTP, HTTPS, HTTPS-Proxy, passive FTP and SSH are supported.