use Socket;
use Net::CIDR;
use Net::RawIP;
+use Time::HiRes;
require './access_list.pl';
require './nets.pl';
+require './survey.pl';
require './mbd.pm';
+use lib '../include';
+use nms;
+use strict;
+use warnings;
+
+my ($dbh, $q);
sub fhbits {
my $bits = 0;
return $bits;
}
+# used for rate limiting
+my %last_sent = ();
+
+# for own surveying
+my %active_surveys = ();
+my %last_survey = ();
+
+my %cidrcache = ();
+sub cache_cidrlookup {
+ my ($addr, $net) = @_;
+ my $key = $addr . " " . $net;
+
+ if (!exists($cidrcache{$key})) {
+ $cidrcache{$key} = Net::CIDR::cidrlookup($addr, $net);
+ }
+ return $cidrcache{$key};
+}
+
+my %rangecache = ();
+sub cache_cidrrange {
+ my ($net) = @_;
+
+ if (!exists($rangecache{$net})) {
+ ($rangecache{$net}) = Net::CIDR::cidr2range($net);
+ }
+
+ return $rangecache{$net};
+}
+
open LOG, ">>", "mbd.log";
-my @ports = mbd::find_all_ports();
+my @ports = ( mbd::find_all_ports() , $Config::survey_port_low .. $Config::survey_port_high );
# Open a socket for each port
my @socks = ();
my $rout;
my $nfound = select($rout=$rin, undef, undef, undef);
+ my $now = [Time::HiRes::gettimeofday];
+
+ # First of all, close any surveys that are due.
+ for my $sport (keys %active_surveys) {
+ my $age = Time::HiRes::tv_interval($active_surveys{$sport}{start}, $now);
+ if ($age > $Config::survey_time && $active_surveys{$sport}{active}) {
+ print "Survey for '" . $Config::access_list[$active_surveys{$sport}{entry}]->{name} . "'/" .
+ $active_surveys{$sport}{dport} . ": " . $active_surveys{$sport}{num} . " active servers.\n";
+ $active_surveys{$sport}{active} = 0;
+
+ # (re)connect to the database if needed
+ if (!defined($dbh) || !$dbh->ping) {
+ $dbh = nms::db_connect();
+ $q = $dbh->prepare("INSERT INTO mbd_log (ts,game,port,description,active_servers) VALUES (CURRENT_TIMESTAMP,?,?,?,?)")
+ or die "Couldn't prepare query";
+ }
+ $q->execute($active_surveys{$sport}{entry}, $active_surveys{$sport}{dport}, $Config::access_list[$active_surveys{$sport}{entry}]->{name}, $active_surveys{$sport}{num});
+ }
+ if ($age > $Config::survey_time * 3.0) {
+ delete $active_surveys{$sport};
+ }
+ }
+
for my $sock (@socks) {
next unless (vec($rout, fileno($sock), 1) == 1);
my ($sport, $saddr) = sockaddr_in($addr);
my ($dport, $daddr) = sockaddr_in(getsockname($sock));
my $size = length($data);
+
+ # Check if this is a survey reply
+ if ($dport >= $Config::survey_port_low && $dport <= $Config::survey_port_high) {
+ if (!exists($active_surveys{$dport})) {
+ print "WARNING: Unknown survey port $dport, ignoring\n";
+ next;
+ }
+ if (!$active_surveys{$dport}{active}) {
+ # remains
+ next;
+ }
+
+ ++$active_surveys{$dport}{num};
+ next;
+ }
+
+ # Rate limiting
+ if (exists($last_sent{$saddr}{$dport})) {
+ my $elapsed = Time::HiRes::tv_interval($last_sent{$saddr}{$dport}, $now);
+ if ($elapsed < 1.0) {
+ print LOG "$dport $size 2\n";
+ print inet_ntoa($saddr), ", $dport, $size bytes => rate-limited ($elapsed secs since last)\n";
+ next;
+ }
+ }
+
# We don't get the packet's destination address, but I guess this should do...
# Check against the ACL.
my $pass = 0;
+ my $entry = -1;
for my $rule (@Config::access_list) {
+ ++$entry;
+
next unless (mbd::match_ranges($dport, $rule->{'ports'}));
next unless (mbd::match_ranges($size, $rule->{'sizes'}));
print LOG "$dport $size $pass\n";
if (!$pass) {
- print "$dport, $size bytes => filtered\n";
+ print inet_ntoa($saddr), ", $dport, $size bytes => filtered\n";
+ next;
}
- next unless $pass;
+ $last_sent{$saddr}{$dport} = $now;
- for my $net (@Config::networks) {
- next if (Net::CIDR::cidrlookup(inet_ntoa($saddr), $net));
+ # The packet is OK! Do we already have a recent enough survey
+ # for this port, or should we use this packet?
+ my $survey = 1;
+ if (exists($last_survey{$entry . "/" . $dport})) {
+ my $age = Time::HiRes::tv_interval($last_survey{$entry . "/" . $dport}, $now);
+ if ($age < $Config::survey_freq) {
+ $survey = 0;
+ }
+ }
+
+ # New survey; find an unused port
+ my $survey_sport;
+ if ($survey) {
+ for my $port ($Config::survey_port_low..$Config::survey_port_high) {
+ if (!exists($active_surveys{$port})) {
+ $survey_sport = $port;
+
+ $active_surveys{$port} = {
+ start => $now,
+ active => 1,
+ dport => $dport,
+ entry => $entry,
+ num => 0
+ };
+ $last_survey{$entry . "/" . $dport} = $now;
+
+ last;
+ }
+ }
- my ($range) = Net::CIDR::cidr2range($net);
+ if (!defined($survey_sport)) {
+ print "WARNING: no free survey source ports, not surveying.\n";
+ $survey = 0;
+ }
+ }
+
+ my $num_nets = 0;
+ for my $net (@Config::networks) {
+ my ($range) = cache_cidrrange($net);
$range =~ /-(.*?)$/;
my $broadcast = $1;
- print inet_ntoa($saddr), ", $dport, $size bytes => $broadcast\n";
+ if ($survey) {
+ $sendsock->set({
+ ip => {
+ saddr => $Config::survey_ip,
+ daddr => $broadcast
+ },
+ udp => {
+ source => $survey_sport,
+ dest => $dport,
+ data => $data
+ }
+ });
+ $sendsock->send;
+ }
+
+ next if (cache_cidrlookup(inet_ntoa($saddr), $net));
$sendsock->set({
ip => {
}
});
$sendsock->send;
+
+ ++$num_nets;
+ }
+
+ if ($survey) {
+ print inet_ntoa($saddr), ", $dport, $size bytes => ($num_nets networks) [+survey from port $survey_sport]\n";
+ } else {
+ print inet_ntoa($saddr), ", $dport, $size bytes => ($num_nets networks)\n";
}
}
}
projects / nms / blobdiff