Mailing List Archive

Author: jm
Date: Tue May 25 18:36:01 2004
New Revision: 20450

Modified:
incubator/spamassassin/trunk/lib/Mail/SpamAssassin/Dns.pm
Log:
bug 3419: use NS queries instead of MX to lessen load

Modified: incubator/spamassassin/trunk/lib/Mail/SpamAssassin/Dns.pm
==============================================================================
--- incubator/spamassassin/trunk/lib/Mail/SpamAssassin/Dns.pm (original)
+++ incubator/spamassassin/trunk/lib/Mail/SpamAssassin/Dns.pm Tue May 25 18:36:01 2004
@@ -952,6 +952,38 @@
return (!$self->{no_resolver});
}

+sub lookup_ns {
+ my ($self, $dom) = @_;
+
+ return unless $self->load_resolver();
+ return if ($self->server_failed_to_respond_for_domain ($dom));
+
+ my $nsrecords;
+ dbg ("looking up NS for '$dom'");
+
+ if (exists $self->{dnscache}->{NS}->{$dom}) {
+ $nsrecords = $self->{dnscache}->{NS}->{$dom};
+
+ } else {
+ eval {
+ my $query = $self->{res}->search($dom, 'NS');
+ my @nses = ();
+ if ($query) {
+ foreach my $rr ($query->answer) {
+ if ($rr->type eq "NS") { push (@nses, $rr->nsdname); }
+ }
+ }
+ $nsrecords = $self->{dnscache}->{NS}->{$dom} = [ @nses ];
+ };
+ if ($@) {
+ dbg ("NS lookup failed horribly, perhaps bad resolv.conf setting?");
+ return undef;
+ }
+ }
+
+ $nsrecords;
+}
+
sub lookup_mx {
my ($self, $dom) = @_;

@@ -1113,7 +1145,7 @@
my $servers=$1;
dbg("servers: $servers");
@domains = split (/\s+/, $servers);
- dbg("Looking up MX records for user specified servers: ".join(", ", @domains), "dnsavailable", -1);
+ dbg("Looking up NS records for user specified servers: ".join(", ", @domains), "dnsavailable", -1);
} else {
@domains = @EXISTING_DOMAINS;
}
@@ -1124,22 +1156,22 @@
for(my $retry = 3; $retry > 0 and $#domains>-1; $retry--) {
my $domain = splice(@domains, rand(@domains), 1);
dbg ("trying ($retry) $domain...", "dnsavailable", -2);
- my $result = $self->lookup_mx_exists($domain);
- if(defined $result) {
+ my $result = $self->lookup_ns($domain);
+ if(defined $result && scalar @$result > 0) {
if ( $result ) {
- dbg ("MX lookup of $domain succeeded => Dns available (set dns_available to hardcode)", "dnsavailable", -1);
+ dbg ("NS lookup of $domain succeeded => Dns available (set dns_available to hardcode)", "dnsavailable", -1);
$IS_DNS_AVAILABLE = 1;
last;
}
}
else {
- dbg ("MX lookup of $domain failed horribly => Perhaps your resolv.conf isn't pointing at a valid server?", "dnsavailable", -1);
+ dbg ("NS lookup of $domain failed horribly => Perhaps your resolv.conf isn't pointing at a valid server?", "dnsavailable", -1);
$IS_DNS_AVAILABLE = 0; # should already be 0, but let's be sure.
last;
}
}

- dbg ("All MX queries failed => DNS unavailable (set dns_available to override)", "dnsavailable", -1) if ($IS_DNS_AVAILABLE == 0);
+ dbg ("All NS queries failed => DNS unavailable (set dns_available to override)", "dnsavailable", -1) if ($IS_DNS_AVAILABLE == 0);

done:
# jm: leaving this in!