Posted By: networ (Packet Mangler) on 'CZunix'
Title:     Re: Port Knocking
Date:      Tue Aug 25 09:45:11 2009

Ja port knocking pouzivam uz par let proti linuxovym serverum. Jako klient 
pouzivam vetsinou svuj skriptik v perlu, zjednoduseny priklad viz nize. Ten 
sleep je tam dobre mit zejm. pro klepani pres GSM site. Server po uspesnem 
zaklepani posle email, takze vidim, ze se nekdo o neco snazi. 

ntw

#!/usr/bin/perl

use IO::Socket::INET;
use Time::HiRes;

$remote_ip = "123.123.123.123";
my @porty = qw(30 799 228 305 4049 2557 783 8245 53249 36864);
my $msg="";
foreach my $port (@porty) {
    $MySocket=new IO::Socket::INET->new(PeerPort=>$port,
            Proto=>'udp',
            Timeout=>1,
            PeerAddr=>$remote_ip);
    $MySocket->send($msg);
    Time::HiRes::usleep(10000);....
}