Merge pull request #174 from jaredj/test-greylisting

Get rid of grey_timeout and 'white' clients

plugins/greylisting

@@ -33,9 +33,9 @@ How that works is best explained by example:
 A new connection arrives from the host shvj1.jpmchase.com. The sender is
 chase@alerts.chase.com and the recipient is londonwhale@example.com. This is
 the first connection for that triplet so the connection is deferred for
-I<black_timeout> minutes. After the timeout, but before the I<grey_timeout>
+I<black_timeout> minutes. After the timeout elapses, shvj1.jpmchase.com retries
-elapses, shvj1.jpmchase.com retries and successfully delivers the mail. For
+and successfully delivers the mail. For the next I<white_timeout> days, emails
-the next I<white_timeout> days, emails for that triplet are not delayed.
+for that triplet are not delayed.
 
 The next day, shvj1.jpmchase.com tries to deliver a new email from
 alerts@alerts.chase.com to jdimon@example.com. Since this triplet is new, it
@@ -73,14 +73,6 @@ e.g. to allow per-recipient logging. Default: 0.
 The initial period during which we issue DENYSOFTs for connections from an
 unknown (or timed out) 'connection triplet'. Default: 50 minutes.
 
-=head2 grey_timeout <timeout_seconds>
-
-The subsequent 'grey' period, after the initial black blocking period,
-when we will accept a delivery from a formerly-unknown connection
-triplet. If a new connection is received during this time, we will
-record a successful delivery against this IP address, which whitelists
-it for future deliveries (see following). Default: 3 hours 20 minutes.
-
 =head2 white_timeout <timeout_seconds>
 
 The period after which a known connection triplet will be considered
@@ -180,8 +172,9 @@ my $VERSION = '0.12';
 
 my $DENYMSG        = "This mail is temporarily denied";
 my %PERMITTED_ARGS = map { $_ => 1 } qw(per_recipient remote_ip sender
-  recipient black_timeout grey_timeout white_timeout deny_late db_dir
+  recipient black_timeout white_timeout deny_late db_dir
   nfslock p0f reject loglevel geoip upgrade );
+$PERMITTED_ARGS{grey_timeout} = 1; # Legacy argument now ignored
 
 my %DEFAULTS = (
                 remote_ip     => 1,
@@ -189,7 +182,6 @@ my %DEFAULTS = (
                 recipient     => 0,
                 reject        => 1,
                 black_timeout => 50 * 60,               # 50m
-                grey_timeout  => 3 * 3600 + 20 * 60,    # 3h:20m
                 white_timeout => 36 * 3600 * 24,        # 36 days
                 nfslock       => 0,
                 p0f           => undef,
@@ -360,7 +352,7 @@ sub greylist {
     my $value = $self->db->get($key);
     if ( ! $value ) {
         # new IP or entry timed out - record new
-        $self->db->set( $key, sprintf $fmt, time, 1, 0, 0 );
+        $self->db->set( $key, sprintf $fmt, $self->now, 1, 0, 0 );
         $self->log(LOGWARN, "fail: initial DENYSOFT, unknown");
         return $self->cleanup_and_return();
     }
@@ -371,8 +363,8 @@ sub greylist {
     if ($white) {
 
         # white IP - accept unless timed out
-        if (time - $ts < $config->{white_timeout}) {
+        if ( $self->now - $ts < $config->{white_timeout} ) {
-            $self->db->set( $key, sprintf $fmt, time, $new, $black, ++$white );
+            $self->db->set( $key, sprintf $fmt, $self->now, $new, $black, ++$white );
             $self->log(LOGINFO, "pass: white, $white deliveries");
             return $self->cleanup_and_return(DECLINED);
         }
@@ -382,24 +374,20 @@ sub greylist {
     }
 
     # Black IP - deny, but don't update timestamp
-    if (time - $ts < $config->{black_timeout}) {
+    if ( $self->now - $ts < $config->{black_timeout} ) {
         $self->db->set( $key, sprintf $fmt, $ts, $new, ++$black, 0 );
         $self->log(LOGWARN,
                    "fail: black DENYSOFT - $black deferred connections");
         return $self->cleanup_and_return();
     }
 
-    # Grey IP - accept unless timed out
-    elsif (time - $ts < $config->{grey_timeout}) {
-        $self->db->set( $key, sprintf $fmt, time, $new, $black, 1 );
-        $self->log(LOGWARN, "pass: updated grey->white");
-        return $self->cleanup_and_return(DECLINED);
-    }
-
     $self->log(LOGWARN, "pass: timed out (grey)");
     return $self->cleanup_and_return(DECLINED);
 }
 
+# This exists purely to be overridden for testing
+sub now { time() }
+
 sub cleanup_and_return {
     my ($self, $return_val) = @_;
 
@@ -461,7 +449,7 @@ sub prune_db {
     my $pruned = 0;
     foreach my $key ( $self->db->get_keys ) {
         my ($ts, $new, $black, $white) = split /:/, $self->db->get($key);
-        my $age = time - $ts;
+        my $age = $self->now - $ts;
         next if $age < $self->{_args}{white_timeout};
         $pruned++;
         $self->db->delete($key);

t/plugin_tests/greylisting

@@ -26,6 +26,7 @@ sub register_tests {
     $self->register_test("test_greylist_p0f_link");
     $self->register_test("test_greylist_p0f_uptime");
     $self->register_test('test_exclude_file_match');
+    $self->register_test('test_greylist');
 }
 
 sub test_load_exclude_files {
@@ -219,6 +220,56 @@ sub test_greylist_p0f_uptime {
     ok( ! $self->p0f_match(), 'p0f uptime miss');
 }
 
+my $mocktime;
+sub test_greylist {
+    my ( $self ) = @_;
+    $self->{_args} = {
+        remote_ip     => 1,
+        sender        => 0,
+        recipient     => 0,
+        reject        => 1,
+        black_timeout => 50 * 60,               # 50m
+        grey_timeout  => 3 * 3600 + 20 * 60,    # 3h:20m
+        white_timeout => 36 * 3600 * 24,        # 36 days
+        p0f           => 0,
+        geoip         => 0,
+    };
+    $self->connection->remote_host('example.com');
+    $self->connection->remote_ip('1.2.3.4');
+    my $sender = Qpsmtpd::Address->new( "<$test_email>" );
+    my $rcpt   = Qpsmtpd::Address->new( "<$test_email>" );
+    my $start = time() - 40 * 3600 * 24; # 40 days ago
+    $mocktime = $start;
+    is( $self->rc( $self->greylist( $self->transaction, $sender, $rcpt ) ),
+        'DENYSOFT: This mail is temporarily denied',
+        'Initial connection attempt greylisted' );
+    $mocktime = $start + 60 * 49;
+    is( $self->rc( $self->greylist( $self->transaction, $sender, $rcpt ) ),
+        'DENYSOFT: This mail is temporarily denied',
+        'Greylisted 49 minutes later' );
+    $mocktime = $start + 60 * 51;
+    is( $self->rc( $self->greylist( $self->transaction, $sender, $rcpt ) ),
+        'DECLINED',
+        'Allowed 51 minutes later' );
+    $mocktime = $start + 60 * 52 + 36 * 3600 * 24;
+    $self->prune_db;
+    is( $self->rc( $self->greylist( $self->transaction, $sender, $rcpt ) ),
+        'DENYSOFT: This mail is temporarily denied',
+        're-greylisted 36 days later' );
+}
+
+{
+    no warnings qw( redefine );
+    sub now { $mocktime || time() }
+}
+
+sub rc {
+    my ( $self, $r, $msg ) = @_;
+    return '' if ! defined $r;
+    return return_code($r) if ! defined $msg;
+    return return_code($r) . ": $msg";
+}
+
 sub _reset_transaction {
     my $self = shift;