1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
|
package MasterServer::UDP::BeaconCatcher;
use strict;
use warnings;
use AnyEvent::Handle::UDP;
use Socket qw(sockaddr_in inet_ntoa);
use Exporter 'import';
our @EXPORT = qw| beacon_catcher on_beacon_receive|;
################################################################################
## Receive UDP beacons with \heartbeat\7778\gamename\ut\ format
## where "ut" is the game name and 7778 the query port of the server.
################################################################################
sub beacon_catcher {
my $self = shift;
# display that the server is up and listening for beacons
$self->log("info", "Listening for UDP beacons on port $self->{beacon_port}.");
# UDP server
my $udp_server;
$udp_server = AnyEvent::Handle::UDP->new(
# Bind to this host and use the port specified in the config file
bind => ['0.0.0.0', $self->{beacon_port}],
# when datagrams are received
on_recv => sub {$self->on_beacon_receive(@_)},
);
# allow object to exist beyond this scope. Objects have ambitions too.
return $udp_server;
}
################################################################################
## Determine the content of the received information and process it.
################################################################################
sub on_beacon_receive {
# $self, beacon address, handle, packed client address
my ($self, $b, $udp, $pa) = @_;
# unpack ip from packed client address
my ($port, $iaddr) = sockaddr_in($pa);
my $peer_addr = inet_ntoa($iaddr);
# assume fraud/crash attempt if response too long
if (length $b > 64) {
# log
$self->log("attack","length exceeded in beacon: $peer_addr:$port sent $b");
# truncate and try to continue
$b = substr $b, 0, 64;
}
# FIXME: note to self: order is important when having combined queries!
# TODO: find a more elegant and long-time solution for this.
# if this is a secure response, verify the response
$self->process_udp_validate($b, $peer_addr, $port, undef)
if ($b =~ m/\\validate\\/);
# if a heartbeat format was detected...
$self->process_udp_beacon($udp, $pa, $b, $peer_addr, $port)
if ($b =~ m/\\heartbeat\\/ && $b =~ m/\\gamename\\/);
# if other masterservers check if we're still alive
$self->process_udp_secure($udp, $pa, $b, $peer_addr)
if ($b =~ m/\\secure\\/ || $b =~ m/\\basic\\/ || $b =~ m/\\status\\/ || $b =~ m/\\info\\/);
}
1;
|
