$type = "06"; #IAX_Control
                       $iax_type = "04"; #ACK
                        $msg = pack "H24", $src_call . $dst_call . $timestamp . $outbound_seq . $inbound_seq . $type . $iax_type;
                       send(PING, $msg, 0, $sendto) == length($msg) or die "cannot send to $target : $target_port : $!\n";

#!/usr/bin/perl -w
#udp ping tool

use IO::Socket;
$target = shift; #"192.168.0.255";
$target_port = 4569;

socket(PING, PF_INET, SOCK_DGRAM, getprotobyname("udp"));

# Build Packet ... 
# Names from ethereal filter of registration packet

$src_call = "8000"; #8000 most siginificant bit is IAX packet type full ... required for a poke etc...
$dst_call = "0000";
$timestamp = "00000000";
$outbound_seq = "00";
$inbound_seq = "00";
$type = "06"; #IAX_Control
$iax_type = "1e"; #POKE
$msg = pack "H24", $src_call . $dst_call . $timestamp . $outbound_seq . $inbound_seq . $type . $iax_type;

# Send UDP packet

$ipaddr = inet_aton($target);
$sendto = sockaddr_in($target_port,$ipaddr);

send(PING, $msg, 0, $sendto) == length($msg) or die "cannot send to $target : $target_port : $!\n";

# Listen for responses... listen for TIMEOUT seconds and report all responders (works for broadcast pings)

$MAXLEN = 1024;
$TIMEOUT = 5;

eval {
local $SIG{ALRM} = sub { die "alarm time out"; };
alarm $TIMEOUT;
$total = 3;
$count = 0;
while ($count < $total) {
  $recvfrom = recv(PING, $msg, $MAXLEN, 0) or die "recv: $!";
  ($port, $ipaddr) = sockaddr_in($recvfrom);
  $respaddr = inet_ntoa($ipaddr);
  print "Response from $respaddr : $port\n";
  $count++;
}

$type = "06"; #IAX_Control
$iax_type = "04"; #ACK
$msg = pack "H24", $src_call . $dst_call . $timestamp . $outbound_seq . $inbound_seq . $type . $iax_type;
send(PING, $msg, 0, $sendto) == length($msg) or die "cannot send to $target : $target_port : $!\n";

};

if ($@) {
       print "Error Timeout waiting for packet from: $target\r\n";
       $type = "06"; #IAX_Control
       $iax_type = "04"; #ACK
       $msg = pack "H24", $src_call . $dst_call . $timestamp . $outbound_seq . $inbound_seq . $type . $iax_type;
       send(PING, $msg, 0, $sendto) == length($msg) or die "cannot send to $target : $target_port : $!\n";
}