tgcd

Index

NAME

SYNOPSIS

DESCRIPTION

OPTIONS

EXAMPLES

SEE ALSO

AVAILABILITY

COPYRIGHT AND LEGAL ISSUES

AUTHOR

DOWNLOAD

RELATED WROKS

NAME

SYNOPSIS

DESCRIPTION

- ConnectConnect (or CC, specified by option -C)
- ListenListen (or LL, specified by option -L)
- Port Forwarder (or PF, specified by option -F)

The ConnectConnect and ListenListen instances of tgcd are used jointly together, while the Port Forwarder mode acts standalone. The ConnectConnect instance resides somewhere on the network (inside the LAN) where it can access the desired server, while the ListenListen will be where the external client can access it (outside the LAN). The ConnectConnect instance, when started, tries to establish a control connection to ListenListen instance (if failed it will retry every n seconds specified by -i ). The ListenListen instance upon receiving a connection from client, will send a request to ConnectConnect (over the already established control connection) to establish a connection to server as well as another connection to ListenListen for data transferring. In the Port Forwarder mode, tgcd will pump data from one port to another providing a basic port forwarding functionality.

For all three modes, one can choose (using -m option) between two different ways of handling multiple connections. By choosing the Select method, the program will use less system memory in expense of slower handling of multiple connections, and on the other side by choosing Fork method tgcd will handle the multiple connections faster in expense of system memory.

tgcd links with libwrap (if available at build time) to provide a simple access control mechanism that's provided by hosts_access(5).

OPTIONS

-C, --ccnode

Become a CC (ConnectConnect) node.

-s, --server <host:port>

The host and port of the actual server

-c, --llhost <host:port>

The host and port of the ListenListen node.

-i, --interval <seconds>

Time interval to periodically report to LL (default: 40s).

-k, --key <number>

poorman's encryption (0-255, default: 0, means no encryption)

-a, --auth <password>

HMAC password to authenticate a control connection with LL In order to use this feature, tgcd must be configured and built with --with-mhash

Options for ListenListen mode:

-L, --llnode

Become a LL (ListenListen) node.

-q, --llport number

The port to listen on for incoming connection from a CC node

-p, --port number

The port to listen of for incoming actual client connection

-e, --interface <interface IP>

The interface for incomming actual client connection (default: all interfaces)

-k, --key number

poorman's encryption (0-255, default: 0, means no encryption)

-a, --auth <password>

HMAC password to authenticate an incoming CC control connection In order to use this feature, tgcd must be configured and built with --with-mhash

Port forwarder options:

-F, --lcnode

Become a ListenConnect node, i.e. just a simple port forwarder

-p, --port number

The port to listen of for incoming actual client connection

-s, --server host:port

The host and port of the destination server

Common options:

-m, --method {f|s}

f: Fork s: Select (default: s)

-l, --log file

Write logs to file. (default:'/dev/null')

-g, --level number

Log level detail (default:0).

-n, --nodaemon

Do not become daemon

-h, --help

Display this.

-v, --version

Display version number.

EXAMPLES

Lets say you'd like to access a localy running WEB server on your work PC from home, this is how to do it:

To run tgcd in CC mode and provide access to the local WEB server :

tgcd -C -s localhost:80 -c my_home_computer:1234

To run tgcd in LL mode on my_home_computer host to provide access to the above service:

tgcd -L -p 8000 -q 1234

This will make the WEB server running on the work PC accessible on port 8000 of my_home_computer.

SEE ALSO

AVAILABILITY

COPYRIGHT AND LEGAL ISSUES

This program is provided with no warranty of any kind, either expressed or implied. It is the responsibility of the user (you) to fully research and comprehend the usage of this program. As with any tool, it can be misused, either intentionally or unintentionally. THE AUTHOR(S) IS(ARE) NOT RESPONSIBLE FOR ANYTHING YOU DO WITH THIS PROGRAM or anything that happens because of your use (or misuse) of this program. THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.  

AUTHOR

DOWNLOAd

RELATED WORKS

- Revinetd, available at: http://revinetd.sourceforge.net

- An implementation using "socat", http://www.dest-unreach.org/socat/doc/socat-gender.txt

- FireWall Tunnel, available at: http://sourceforge.net/projects/firewall-tunnel/

- An artile explaining the idea