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SSLH(1)		      User Contributed Perl Documentation	       SSLH(1)

NAME
       sslh - Switch incoming connection between SSH and SSL/HTTPS servers

SYNOPSIS
       sslh [A -vA ] [A	-pA [host:]portA ] [A -tA timeoutA ]
	    [A --sshA [host:]portA ] [A	--sslA [host:]portA ]

DESCRIPTION
       sslh is a simple	script that lets you switch an incoming	connection on
       a single	port between distinct SSH and SSL/HTTPS	servers.

       sslh listens for	connections on a port and is able to redirect them
       either to an HTTPS web server or	a SSH server.

       This lets one setup both	a HTTPS	web server and a SSH server and	access
       them through the	same host+port.

OPTIONS
       The program follows the usual GNU command line syntax, with long
       options starting	with two dashes.

       -p, --port [host:]port
	   The port the	proxy will listen to.  If no port is given, 443	is
	   used	by default.  If	no host	is given, "localhost" is used by
	   default.

       -s, --ssh [host:]port
	   The SSH server which	the SSH	connections must be forwarded to.  If
	   omitted, the	default	is localhost:22.

       -l, --ssl, --https [host:]port
	   The HTTPS server which the HTTPS connections	must be	forwarded to.
	   If omitted, the default is localhost:443.

       -t, --timeout delay
	   Timeout in seconds before a silent incoming connection is
	   considered as a SSH connection. The number can be fractional.

	   The default is 2seconds.

       -v, --verbose
	   Verbose output.  This option	can be used several times for more
	   verbose output.

EXAMPLE	OF USE
       Is this tool actually useful? Yes.

       For example one can use it to access both a SSH server and a secure web
       server via a corporate proxy that only accepts to relay connections to
       port 443. Creating a tunnel that	passes SSH connection through a
       CONNECT-enabled web proxy is easy with connect-tunnel (also included in
       the "Net::Proxy"	distribution).

       The proxy will let both SSH and HTTPS connections out (since they all
       point to	port 443), and the home	server will connect those incoming
       connections to the appropriate server. This only	requires to run	the
       HTTPS server on a non standard port (not	443).

TECHNICAL NOTE
       How can this proxy find out what	kind of	protocol is using a TCP
       connection to port 443, without being connected (yet) to	the server?
       We actually rely	on a slight difference between the SSL and SSH
       protocols (found	thanks to ethereal):

       SSH Once	the TCP	connection is established, the server speaks first,
	   presenting itself by	saying something like:

	       SSH-2.0-OpenSSH_3.6.1p2 Debian 1:3.6.1p2-1

       SSL With	SSL, it's always the client that speaks	first.

       This means that sslh can	be used	with any pair of protocols/services
       that share this property	(the client speaks first for one and the
       server speaks first for the other).

AUTHORS
       Original	idea and C version
	   FrA(C)dA(C)ric PlA(C) "<frederic.ple+sslh@gmail.com>".

       Perl versions
	   Philippe 'BooK' Bruhat "<book@cpan.org>".

SCRIPT HISTORY
       Version 0.01 of the script was a	quick hack designed in 2003 as a proof
       of concept.

       Version 0.02 (and higher) are based on "Net::Proxy", and	included with
       the "Net::Proxy"	distribution. Version 0.02 didn't work,	though.

       Version 0.03 correctly initialised the "in" connector.

       Version 0.04 lets the proxy listen on any address (instead of
       "localhost", which is still the default). Thanks	to Dieter Voegtli for
       spotting	this.

SEE ALSO
       Net::Proxy, Net::Proxy::Connector::dual.

COPYRIGHT
       Copyright 2003-2008, Philippe Bruhat. All rights	reserved.

LICENSE
       This module is free software; you can redistribute it or	modify it
       under the same terms as Perl itself.

perl v5.32.0			  2014-11-02			       SSLH(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLE OF USE | TECHNICAL NOTE | AUTHORS | SCRIPT HISTORY | SEE ALSO | COPYRIGHT | LICENSE

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