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Telnet Gateway

The Telnet Gateway (telgate.js) module allows users of your system's Terminal Server to connect to other TCP/Telnet services on the Internet through your BBS. Typically, these services would be other telnetable BBSes, door game servers, and MUDs, although really, you can theoretically create a gate to any single-port TCP service (e.g. POP3, but not FTP).

The module itself (exec/telgate.js) is just a thin wrapper around the JavaScript function: bbs.telnet_gate()

Usage

The Telnet Gateway module is normally executed via a command-line configured in SCFG, often as an “External Program”. By convention, JavaScript modules are executed from the Synchronet Terminal Server by starting the command-line with a question mark (?) symbol. An asterisk (*) prefix will also work, but will fallback to execute the old exec/telgate.bin if the telgate.js file is absent.

Command-line

The Telnet Gateway module accepts command-line arguments to control its behavior when invoked. The command-line syntax is:

?telgate <address>[:port] [mode] [options]

Where:

  • <address> is the IPv4 address or host name to connect to
  • [:port] is the optional TCP port number to connect to (default is 23)
  • [mode] is an optional set of telgate mode flags (TG_*) OR'd together the pipe (|) symbol
  • [options] are one or more of the following options:
Option Value Description
-T connect-timeout-seconds Connection timeout (default: 10 seconds)
-m telnet-gateway-mode Set of one or more telgate mode flags (TG_*) separated by pipe (|) symbols (default is 0)
-q none Don't display banner or pause prompt (be quiet)
-P none Don't pause for user key-press before connection attempt
-C none Don't clear screen after successful session
-s characters Send string of characters after connecting (may be used multiple times)
-S characters Send CRLF-terminated string of characters after connecting (may be used multiple times)

Option values may immediately following the option flag or may be provided as the next argument on the command-line (separated by white-space).

Address

The <address> argument is the destination address in the format: <IP address or hostname>[:port]

If the TCP port number is not specified, the default is 23 (standard for telnet).

Examples <address> values:

  • vert.synchro.net
  • 24.0.193.46
  • retromud.org:3000

Mode

The valid mode flags (defined in exec/load/sbbsdefs.js) are:

Flag Description
TG_ECHO Echo back to the user's client what it sends (i.e. keyboard input)
TG_CRLF Expand sole CR (on input) to CRLF
TG_LINEMODE Send entire lines only
TG_NODESYNC Call Nodesync, get msgs, etc.
TG_CTRLKEYS Interpret control key (e.g. Ctrl-P, Ctrl-U, Ctrl-T, etc.) locally
TG_PASSTHRU Pass-through Telnet commands/responses (don't proxy the Telnet command responses)
TG_RLOGIN Use BSD RLogin protocol (not Telnet)
TG_NOCHKTIME Don't check time left online
TG_NOTERMTYPE Request client “DONT TERM_TYPE”
TG_NOLF Do not send line-feeds
TG_RLOGINSWAP Swap the RLogin alias/real-names

Multiple mode flags may be specified by ORing them together with the pipe (|) character, like so:

TG_ECHO|TG_CRLF

Others

Although telgate.js is the original and most flexible Synchronet Telnet gateway script, there are other bbs.telnet_gate() wrapper scripts available for your convenience:

Module Description
mudgate.js Sets the mode flags based on the needs of a typical MUD server
unixgate.js Sets the mode flags based on the needs of a typical Unix Telnet server
rlogin.js Actually a wrapper around the bbs.rlogin_gate JavaScript function

Examples

To set-up an external gateway to another BBS in SCFG->External Programs->Online Programs:

Command line: "?telgate vert.synchro.net"

To set-up an external gateway to a MUD:

Command line: "?mudgate batmud.bat.org"

To set-up an external gateway to a Trade Wars Game Server (TWGS):

Command line: "?rlogin twgs.someserver.com"

While using the telnet gateway (and not currently in telnet “Binary” mode), users can press ctrl-] for a menu of telnet gate commands including: Disconnect, Toggle Echo, List Users, and Private Message.

Legacy

The Baja TELNET_GATE function and the corresponding exec/*gate.bin files have been deprecated. Use the corresponding JavaScript alternatives instead.

See Also