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dns2tcpc(1)		    General Commands Manual		   dns2tcpc(1)

NAME
       dns2tcpc	- A tunneling tool that	encapsulate TCP	traffic	over DNS.

SYNOPSIS
       dns2tcpc	 [  -h ] [ -c ]	[ -z domain zone ] [ -d	debug_level ] [	-r re-
       source ]	[ -k key ] [ -f	config_file ] [	-e command ] [ -T request type
       ] [ -l local_port ] [ server ]

DESCRIPTION
       dns2tcpc	 is  a	network	tool used to encapsulate TCP communications in
       DNS. When connections are received on a specific	port all  TCP  traffic
       is  sent	to the remote dns2tcpd server and forwarded to a specific host
       and port. Multiple connections are supported.

       dns2tcpc	was written for	demonstration purposes.

OPTIONS
       -h     Help Menu

       -c     Enable DNS compression. When used, be sure that  all  relay  and
	      DNS server support compression and really	use it.

       -z domain zone
	      Use this domain as endpoint.

       -d debug	level
	      Change debug level. Levels available are 1, 2 or 3.

       -r resource
	      Remote resource to access.

       -k key Pre shared key used for authentication (identification).

       -f config file
	      Configuration file to use.

       -T request type
	      Request type to use. Actually only KEY and TXT requests are sup-
	      ported.

       -e command
	      Command to execute, I/O are redirected in	the tunnel.

       -l local_port
	      Local port accepting incomming connections (or -	for  stdin  on
	      UNIX systems).

       -t connection timeout
	      Maximum  DNS  server's answer delay in seconds. A	valid delay is
	      between 1	and 240	seconds. Default is 3.

       server DNS server to use. The first entry in resolv.conf	file  will  be
	      choosen if the server is not specified.

CONFIGURATION FILES
       By default ${HOME}/.dns2tcprc is	used if	no configuration file is spec-
       ified. Here is an example :

	      domain = dns2tcp.hsc.fr
	      resource = ssltunnel
	      local_port = 4430
	      enable_compression = 0
	      debug_level = 1
	      key = mykey
	      #	DNS to use
	      server = ns.hsc.fr

EXAMPLES
       dns2tcpc	-k mykey -z dns2tcp.hsc.fr mydns

	      Ask the dns2tcp server to	list available resources.

       ssh -o 'ProxyCommand dns2tcpc -r	ssh -l - -z  dns2tcp.hsc.fr  -k	 mykey
       mydns' myserver

	      Use  dns2tcp  as	a proxy	command	with ssh. We try to connect to
	      the ssh resource with the	key 'mykey' and	the DNS	mydns.

       dns2tcpc	-r socat-resource -e '/bin/bash	-i' -k mykey -z	dns2tcp.hsc.fr
       mydns

	      Use  dns2tcp as a	reverse	shell, the remote shell	will appear on
	      the socat-resource.

       dns2tcpc	-d 1 -f	/dev/null -r ssl-tunnel	-l 2000	-k mykey   -T  KEY  -z
       dns2tcp.hsc.fr mydns

	      Do  not use the default configuration file, bind local port 2000
	      and forward all the traffic on the remote	 ssl-tunnel  resource,
	      use the first debug level. Use KEY type DNS requests.

AUTHORS
       Olivier Dembour <olivier.dembour@hsc.fr>

SEE ALSO
       ssltunnel

								   dns2tcpc(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | CONFIGURATION FILES | EXAMPLES | AUTHORS | SEE ALSO

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