use IO::Socket::INET;
use warnings;
use strict;

# auto-flush on socket
$| = 1;

my $port_server = 9000; # Port des MITM-Server
my $host_server = "127.0.0.1"; # IP-Adresse des MITM-Servers

# example data
# $data     = "\x00\x01\x12\x34\x5A\x86";
# $response = "\x00\x03\x05\x27";

# create a connecting socket
# => Wir sind der Client fuer das Endgeraet
my $socket_client = new IO::Socket::INET (
  PeerHost => $host_server,
  PeerPort => $port_server,
  Proto => 'tcp',
);
die "cannot connect to the server $!\n" unless $socket_client;
print "client-part connected to the server (endpoint)\n";

# my $data = "\x00\x01\x12\x34\x5A\x86";
my $data = "test";
my $data_hex = $data;
$data_hex =~ s/(.)/sprintf("\\x%02X",ord($1))/eg;

my $size = $socket_client->send($data);
print "mitm client sent data of length ".$size." (".$data.")\n";

if (undef($size) || $size == 0)
{
  my $size2 = $socket_client->send($data_hex);
  print "mitm client sent hex-data of length ".$size2." (".$data_hex.")\n";
}

# notify server that request has been sent
shutdown($socket_client, 1);

# receive a response of up to 1024 characters from server
my $response = "";
$socket_client->recv($response, 1024);
my $response_hex = $response;
$response_hex =~ s/(.)/sprintf("\\x%02X",ord($1))/eg;
print "mitm client received response: $response\n";
print " hex: (".$response_hex.")\n";


$socket_client->close();