block telnet to specific port Post: 17865

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Special Forums IP Networking block telnet to specific port Post 17865 by thomas.jones on Wednesday 20th of March 2002 07:51:00 PM

03-20-2002

Registered User

First of all, the standard telnet port is 23. If you have telnet enabled through inetd.conf...then it's probably the default port of 23. Now to stop port 80 access it's just a little different.

If you had a webserver available on your node....then a person telnetting to it will get the httpd system banner:

**********************
Whatever Linux v2.2.14
Apache vX.X.XX
etc.
**********************

They can then send a GET command using telnet to pull the HTML...this is exactly what a web browser does.

To stop someone from connecting to this port...all you have to do is go into inetd.conf and comment out the HTTP line....which should look something like this:

http stream tcp nowait nobody ?/var/www/server/httpd httpd

This will shutdown the daemon...or "service"......then no one will be able to connect to it. Restart the inetd daemon by issuing the following command:

killall -HUP inetd

BTW, you will NOT be able to block a telnet'd connection to your port....and allow a web browser. To the firewall, they are essentially the same traffic. [TCP from a 1024+ port]

HTH.

Last edited by thomas.jones; 03-20-2002 at 09:01 PM..

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LEARN ABOUT DEBIAN

roarmonhttp

roarmonhttp(1)						 System User's Manual: roarmonhttp					    roarmonhttp(1)

NAME

       roarmonhttp - CGI and inetd based streaming server emulation for RoarAudio

SYNOPSIS

       roarmonhttp [--inetd]

DESCRIPTION

       This  program  emulates	a streaming server using RoarAudio.  It can be run from via a webserver as CGI or via inetd in inetd mode.  IN CGI
       mode it is limited to client (listener) HTTP connections.  In inetd mode it can handle source clients and gopher, too.  There  is  no  need
       for a specal port for gopher. The protocol is detected per client at runtime.

OPTIONS

       --inetd
	      Enables inetd mode.

       --server SERVER
	      Set Server to connect to. This may be usfull in inetd mode.

       --rate, --bits, --channels, --codec
	      Sets the default rate, bits, channels or codec.  Those option taking a argument for the given option. Codec names may be used.

       --rel-id SID
	      Set the stream ID for the stream this stream is relative to.

       --help Show a brief help.

EXAMPLES

       Here is an example of a roarmonhttp listening on port 8000 using inetd:
	8000 stream tcp nowait roard /usr/bin/roarmonhttp roarmonhttp --inetd

SEE ALSO

       inetd(8), inetd.conf(5), roartips(7), libroar(7), RoarAudio(7).

HISTORY

       For history information see RoarAudio(7).

RoarAudio							   January 2010 						    roarmonhttp(1)

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