#!/usr/bin/perl
# Simple DHCP client - sending a broadcasted DHCP Discover request

use IO::Socket::INET;
use Net::DHCP::Packet;
use Net::DHCP::Constants;

use POSIX qw(setsid strftime);

# sample logger
sub logger{
    my $str = shift;
    print STDOUT strftime "[%d/%b/%Y:%H:%M:%S] ", localtime;
    print STDOUT "$str\n";
}

logger("DHCPd tester - dummy client");

logger("Opening socket");
$handle = IO::Socket::INET->new(Proto => 'udp',
                                Broadcast => 1,
                                PeerPort => '67',
                                LocalPort => '68',
                                PeerAddr => '127.0.0.1')
      || die "Socket creation error: $@\n";     # yes, it uses $@ here

# create DHCP Packet DISCOVER
$discover = Net::DHCP::Packet->new(
                      Xid => 0x12345678,
                      DHO_DHCP_MESSAGE_TYPE() => DHCPDISCOVER(),
                      DHO_VENDOR_CLASS_IDENTIFIER() => 'foo',
                      );

logger("Sending DISCOVER to 127.0.0.1:67");
logger($discover->toString());
$handle->send($discover->serialize())
              or die "Error sending:$!\n";

logger("Waiting for response from server");
$handle->recv($buf, 4096) || die("recv:$!");
logger("Got response");
$response = new Net::DHCP::Packet($buf);
logger($response->toString());

# create DHCP Packet REQUEST
$request = Net::DHCP::Packet->new(
                      Xid => 0x12345678,
                      Ciaddr => $response->yiaddr(),
                      DHO_DHCP_MESSAGE_TYPE() => DHCPREQUEST(),
                      DHO_VENDOR_CLASS_IDENTIFIER() => 'foo',
                      DHO_DHCP_REQUESTED_ADDRESS() => $response->yiaddr(),
                      );

logger("Sending REQUEST to 127.0.0.1:67");
logger($request->toString());

$handle->send($request->serialize())
              or die "Error sending:$!\n";
logger("Waiting for response from server");
$handle->recv($buf, 4096) || die("recv:$!");
logger("Got response");
$response = new Net::DHCP::Packet($buf);
logger($response->toString());