NAME
x-gw - X gateway service
SYNOPSIS
x-gw [display/hostname]
DESCRIPTION
x-gw provides a user-level X connection service under tn-gw and rlogin-gw access control. Clients may be started on arbitrary internet hosts, and request to display on a virtual display running on the firewall. When the connection request arrives, x-gw pops up a window on the user's real display which asks for confirmation before permitting the connection. If granted, x-gw passes data between the virtual display and the user's real display.
Previously, in order to run X through the firewall, exceptions has to be made in router configuration rules to permit direct connectivity to ports from 6000 to 6100 on internal systems. x-gw searches for an unused lowest port for the X connection starting from 6010 and listening for connections.
Each time an X client application on a remote system starts, a control connection window will pop up on the user's screen that asks for confirmation before permitting the connection. If granted, the connection is handled by an individual x-gw child daemon to serve multiple simultaneous connections seperately with its own buffed data flow. The child daemon cleans up the buffed data and exits if a connection is closed by either end.
EXAMPLE
sol-> telnet wxu Trying 192.33.112.194... Connected to wxu.tis.com. Escape character is '^]'. wxu.tis.com telnet proxy (Version V1.3) ready: tn-gw-> x tn-gw-> exit Disconnecting... Connection closed by foreign host.
A window pops up on the user's screen which shows the port number of the proxy to use, and which acts as the control window. Clicking on the exit button will close all multiple simultaneous X connections.
OPTIONS
- display/hostname
-
specify a destination display where the user wants applications to appear. By default x-gw will use the connecting host name followed by port number: 0.0, if the argument is not specified. The 0.0 port is also a default number if the user sets the display to a host name.
INSTALLATION
To install x-gw first place the excutable in a system area, then modify netperm-table to reflect the appropriate excutable path. The location of x-gw is compiled into the components of the firewall tookit in tn-gw and rlogin-gw based on the netperm-table.