[PATCH] refactored dnsbl, sprinkling logs and tests on it

refactored dnsbl, sprinkling logs and tests on it

---
plugins/dnsbl        |  152 ++++++++++++++++++++++++++++----------------------
t/plugin_tests/dnsbl |   76 ++++++++++++++++++++-----
2 files changed, 149 insertions(+), 79 deletions(-)

diff --git a/plugins/dnsbl b/plugins/dnsbl
index f64012a..62fd862 100644
--- a/plugins/dnsbl
+++ b/plugins/dnsbl
@@ -13,43 +13,32 @@ a configurable set of RBL services.

sub register {
  my ($self, $qp, $denial ) = @_;
-  if ( defined $denial and $denial =~ /^disconnect$/i ) {
+  if ( defined $denial && $denial =~ /^disconnect$/i ) {
    $self->{_dnsbl}->{DENY} = DENY_DISCONNECT;
  }
  else {
    $self->{_dnsbl}->{DENY} = DENY;
  }
-
}

sub hook_connect {
  my ($self, $transaction) = @_;

-  my $remote_ip = $self->qp->connection->remote_ip;
-
-  # perform RBLSMTPD checks to mimic Dan Bernstein's rblsmtpd
-  if (defined($ENV{'RBLSMTPD'})) {
-    if ($ENV{'RBLSMTPD'} ne '') {
-      $self->log(LOGINFO, "RBLSMTPD=\"$ENV{'RBLSMTPD'}\" for $remote_ip");
-      return DECLINED;
-    } else {
-      $self->log(LOGINFO, "RBLSMTPD set, but empty for $remote_ip");
-      return DECLINED;
-    }
-  } else {
-    $self->log(LOGDEBUG, "RBLSMTPD not set for $remote_ip");
-  }
-
-  my $allow = grep { s/\.?$/./; $_ eq substr($remote_ip . '.', 0, length $_) } $self->qp->config('dnsbl_allow');
-  return DECLINED if $allow;
+    # perform RBLSMTPD checks to mimic Dan Bernstein's rblsmtpd
+    return DECLINED if $self->is_set_rblsmtpd();
+    return DECLINED if $self->ip_whitelisted();

  my %dnsbl_zones = map { (split /:/, $_, 2)[0,1] } $self->qp->config('dnsbl_zones');
-  return DECLINED unless %dnsbl_zones;
+    if ( ! %dnsbl_zones ) {
+        $self->log( LOGDEBUG, "skip: no list configured");
+        return DECLINED;
+    };

-  my $reversed_ip = join(".", reverse(split(/\./, $remote_ip)));
+  my $remote_ip = $self->qp->connection->remote_ip;
+  my $reversed_ip = join('.', reverse(split(/\./, $remote_ip)));

-  # we should queue these lookups in the background and just fetch the
-  # results in the first rcpt handler ... oh well.
+  # we queue these lookups in the background and fetch the
+  # results in the first rcpt handler

  my $res = new Net::DNS::Resolver;
  $res->tcp_timeout(30);
@@ -64,7 +53,8 @@ sub hook_connect {
    if (defined($dnsbl_zones{$dnsbl})) {
      $self->log(LOGDEBUG, "Checking $reversed_ip.$dnsbl for A record in the background");
      $sel->add($res->bgsend("$reversed_ip.$dnsbl"));
-    } else {
+    }
+    else {
      $self->log(LOGDEBUG, "Checking $reversed_ip.$dnsbl for TXT record in the background");
      $sel->add($res->bgsend("$reversed_ip.$dnsbl", "TXT"));
    }
@@ -76,32 +66,70 @@ sub hook_connect {
  return DECLINED;
}

+sub is_set_rblsmtpd {
+    my $self = shift;
+
+    my $remote_ip = $self->qp->connection->remote_ip;
+
+    if ( ! defined $ENV{'RBLSMTPD'} ) {
+        $self->log(LOGDEBUG, "RBLSMTPD not set for $remote_ip");
+        return;
+    };
+
+    if ($ENV{'RBLSMTPD'} ne '') {
+        $self->log(LOGINFO, "RBLSMTPD=\"$ENV{'RBLSMTPD'}\" for $remote_ip");
+        return $ENV{'RBLSMTPD'};
+    }
+
+    $self->log(LOGINFO, "RBLSMTPD set, but empty for $remote_ip");
+    return 1;  # don't return empty string, it evaluates to false
+};
+
+sub ip_whitelisted {
+    my ($self) = @_;
+
+    my $remote_ip = $self->qp->connection->remote_ip;
+    my $white = $self->qp->connection->notes('whitelisthost');
+    if ( $white ) {
+        $self->log(LOGDEBUG, "skip: whitelist overrode blacklist: $white");
+        return 1;
+    };
+
+    if ( $self->qp->connection->relay_client() ) {
+        $self->log(LOGWARN, "skip: don't blacklist relay/auth clients");
+        return 1;
+    };
+
+    return grep { s/\.?$/./;
+            $_ eq substr($remote_ip . '.', 0, length $_)
+        }
+        $self->qp->config('dnsbl_allow');
+};
+
sub process_sockets {
  my ($self) = @_;

  my $conn = $self->qp->connection;

-  return $conn->notes('dnsbl') 
-    if $conn->notes('dnsbl');
+  return $conn->notes('dnsbl') if $conn->notes('dnsbl');

  my %dnsbl_zones = map { (split /:/, $_, 2)[0,1] } $self->qp->config('dnsbl_zones');

+  my $sel       = $conn->notes('dnsbl_sockets') or return '';
+  my $dom       = $conn->notes('dnsbl_domains');
+  my $remote_ip = $self->qp->connection->remote_ip;
+
+  my $result;
  my $res = new Net::DNS::Resolver;
  $res->tcp_timeout(30);
  $res->udp_timeout(30);

-  my $sel = $conn->notes('dnsbl_sockets') or return "";
-  my $dom = $conn->notes('dnsbl_domains');
-  my $remote_ip = $self->qp->connection->remote_ip;
-
-  my $result; 
-
  $self->log(LOGDEBUG, "waiting for dnsbl dns");

  # don't wait more than 8 seconds here
  my @ready = $sel->can_read(8);

-  $self->log(LOGDEBUG, "DONE waiting for dnsbl dns, got " , scalar @ready, " answers ...") ;
+  $self->log(LOGDEBUG, "DONE waiting for dnsbl dns, got ", scalar @ready, " answers ...");
  return '' unless @ready;

  for my $socket (@ready) {
@@ -114,16 +142,16 @@ sub process_sockets {
    if ($query) {
      my $a_record = 0;
      foreach my $rr ($query->answer) {
-	my $name = $rr->name;
-	$self->log(LOGDEBUG, "name $name");
-	next unless $dom->{$name};
-	$self->log(LOGDEBUG, "name $name was queried");
-	$a_record = 1 if $rr->type eq "A";
-	($dnsbl) = ($name =~ m/(?:\d+\.){4}(.*)/) unless $dnsbl;
-	$dnsbl = $name unless $dnsbl;
-	next unless $rr->type eq "TXT";
-	$self->log(LOGDEBUG, "got txt record");
-	$result = $rr->txtdata and last;
+        my $name = $rr->name;
+        $self->log(LOGDEBUG, "name $name");
+        next unless $dom->{$name};
+        $self->log(LOGDEBUG, "name $name was queried");
+        $a_record = 1 if $rr->type eq "A";
+        ($dnsbl) = ($name =~ m/(?:\d+\.){4}(.*)/) unless $dnsbl;
+        $dnsbl = $name unless $dnsbl;
+        next unless $rr->type eq "TXT";
+        $self->log(LOGDEBUG, "got txt record");
+        $result = $rr->txtdata and last;
      }
      #$a_record and $result = "Blocked by $dnsbl";

@@ -132,7 +160,8 @@ sub process_sockets {
          $result = $dnsbl_zones{$dnsbl};
          #$result =~ s/%IP%/$ENV{'TCPREMOTEIP'}/g;
          $result =~ s/%IP%/$remote_ip/g;
-        } else {
+        }
+        else {
          # shouldn't get here?
          $result = "Blocked by $dnsbl";
        }
@@ -140,7 +169,7 @@ sub process_sockets {
    }
    else {
      $self->log(LOGERROR, "$dnsbl query failed: ", $res->errorstring)
-	unless $res->errorstring eq "NXDOMAIN";
+        unless $res->errorstring eq "NXDOMAIN";
    }

    if ($result) {
@@ -162,39 +191,31 @@ sub process_sockets {
  $conn->notes('dnsbl_sockets', undef);

  return $conn->notes('dnsbl', $result);
-
}

sub hook_rcpt {
  my ($self, $transaction, $rcpt, %param) = @_;
-  my $connection = $self->qp->connection;

  # RBLSMTPD being non-empty means it contains the failure message to return
  if (defined ($ENV{'RBLSMTPD'}) && $ENV{'RBLSMTPD'} ne '') {
    my $result = $ENV{'RBLSMTPD'};
-    my $remote_ip = $connection->remote_ip;
+    my $remote_ip = $self->qp->connection->remote_ip;
    $result =~ s/%IP%/$remote_ip/g;
-    return ($self->{_dnsbl}->{DENY}, 
-	join(" ", $self->qp->config('dnsbl_rejectmsg'), $result));
+    my $msg =  $self->qp->config('dnsbl_rejectmsg');
+    $self->log(LOGINFO, $msg);
+    return ($self->{_dnsbl}->{DENY}, join(' ', $msg, $result));
  }

-  my $note = $self->process_sockets;
-  my $whitelist = $connection->notes('whitelisthost');
-  if ( $note ) {
+    my $note = $self->process_sockets or return DECLINED;
+    return DECLINED if $self->ip_whitelisted();
+
    if ( $rcpt->user =~ /^(?:postmaster|abuse|mailer-daemon|root)$/i ) {
-      $self->log(LOGWARN, "Don't blacklist special account: ".$rcpt->user);
-    }
-    elsif ( $whitelist ) {
-      $self->log(LOGWARN, "Whitelist overrode blacklist: $whitelist");
-    }
-    elsif ( $connection->relay_client() ) {
-      $self->log(LOGWARN, "Don't blacklist relay/auth clients");
-    }
-    else {
-      return ($self->{_dnsbl}->{DENY}, $note);
+        $self->log(LOGWARN, "skip: don't blacklist special account: ".$rcpt->user);
+        return DECLINED;
    }
-  }
-  return DECLINED;
+
+    $self->log(LOGINFO, 'fail');
+    return ($self->{_dnsbl}->{DENY}, $note);
}

sub hook_disconnect {
@@ -205,7 +226,6 @@ sub hook_disconnect {
  return DECLINED;
}

-
=head1 Usage

Add the following line to the config/plugins file:
diff --git a/t/plugin_tests/dnsbl b/t/plugin_tests/dnsbl
index d36651d..e785d65 100644
--- a/t/plugin_tests/dnsbl
+++ b/t/plugin_tests/dnsbl
@@ -1,27 +1,77 @@
+#!perl -w
+
+use strict;
+use warnings;
+
+use Qpsmtpd::Constants;

sub register_tests {
    my $self = shift;
-    $self->register_test("test_local", 1);
-    $self->register_test("test_returnval", 1);
+
+    $self->register_test('test_hook_connect', 2);
+    $self->register_test('test_hook_rcpt', 2);
+    $self->register_test('test_ip_whitelisted', 3);
+    $self->register_test('test_is_set_rblsmtpd', 4);
+    $self->register_test('test_hook_disconnect', 1);
}

-sub test_local {
+sub test_ip_whitelisted {
+    my $self = shift;
+
+    $self->qp->connection->remote_ip('10.1.1.1');
+
+    $self->qp->connection->relay_client(1);
+    ok( $self->ip_whitelisted('10.1.1.1'), "ip_whitelisted, +");
+
+    $self->qp->connection->relay_client(0);
+    ok( ! $self->ip_whitelisted('10.1.1.1'), "ip_whitelisted, -");
+
+    $self->qp->connection->notes('whitelisthost', 'hello honey!');
+    ok( $self->ip_whitelisted('10.1.1.1'), "ip_whitelisted, +");
+    $self->qp->connection->notes('whitelisthost', undef);
+};
+
+sub test_is_set_rblsmtpd {
+    my $self = shift;
+
+    $self->qp->connection->remote_ip('10.1.1.1');
+    ok( ! defined $self->is_set_rblsmtpd('10.1.1.1'), "is_set_rblsmtpd, undef");
+
+    $ENV{RBLSMTPD} = "Yes we can!";
+    cmp_ok( 'Yes we can!','eq',$self->is_set_rblsmtpd('10.1.1.1'), "is_set_rblsmtpd, value");
+
+    $ENV{RBLSMTPD} = "Oh yeah?";
+    cmp_ok( 'Oh yeah?','eq',$self->is_set_rblsmtpd('10.1.1.1'), "is_set_rblsmtpd, value");
+
+    $ENV{RBLSMTPD} = '';
+    cmp_ok( 1,'==',$self->is_set_rblsmtpd('10.1.1.1'), "is_set_rblsmtpd, empty");
+};
+
+sub test_hook_connect {
    my $self = shift;
-    
+
    my $connection = $self->qp->connection;
    $connection->remote_ip('127.0.0.2'); # standard dnsbl test value
-    
-    $self->hook_connect($self->qp->transaction);
-    
-    ok($self->qp->connection->notes('dnsbl_sockets'));
+
+    cmp_ok( DECLINED, '==', $self->hook_connect($self->qp->transaction),
+        "hook_connect +");
+
+    ok($connection->notes('dnsbl_sockets'), "hook_connect, sockets");
+    ok($connection->notes('dnsbl_domains'), "hook_connect, domains");
}

-sub test_returnval {
+sub test_hook_rcpt {
    my $self = shift;

    my $address = Qpsmtpd::Address->parse('<[email protected]>');
-    my ($ret, $note) = $self->hook_rcpt($self->qp->transaction,
-      $address);
-    is($ret, DENY, "Check we got a DENY");
-    print("# dnsbl result: $note\n");
+    my ($ret, $note) = $self->hook_rcpt($self->qp->transaction, $address);
+    is($ret, DENY, "Check we got a DENY ($note)");
+    #print("# dnsbl result: $note\n");
}
+sub test_hook_disconnect {
+    my $self = shift;
+
+    cmp_ok( DECLINED, '==', $self->hook_connect($self->qp->transaction),
+        "hook_disconnect +");
+}
+
-- 
1.7.9.6