Initial checkin.

Signed-off-by: Thomas Hochstein <thh@thh.name>

MOD/Spamfilter.pm

@@ -0,0 +1,142 @@
+######################################################################
+#
+# $Id: Spamfilter.pm 147 2009-10-13 14:46:07Z alba $
+#
+# Copyright 2007 - 2009 Roman Racine
+# Copyright 2009 Alexander Bartolich
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+######################################################################
+#
+# this is a spamfilter which checks incoming mails and marks them
+# as probable Spam.
+#
+# Heuristics are added as needed.
+#
+# The main function "spamfilter" returns 
+# -1 -> discard (post do de.admin.news.announce)
+#  0-5 -> no spam, 
+#  >5 -> spam
+#
+######################################################################
+package MOD::Spamfilter;
+
+use strict;
+use warnings;
+use News::Article;
+use Mail::SpamAssassin;
+use Text::Language::Guess;
+
+$MOD::Spamfilter::VERSION = 0.02;
+
+sub spamfilter;
+sub blacklist;
+sub spamlearn;
+sub new($);
+1;
+
+sub new($) {
+  my (undef,$configref) = @_;
+  my $self = {};
+  $self->{'config'} = $configref;
+  bless $self;
+  return $self;
+}    
+
+
+sub spamfilter_attachment {
+     my ($self,$article) = @_;
+     my $score = 0;
+     if (defined($article->header('Content-Type')) and  $article->header('Content-Type') =~
+	 /^multipart\/(?:mixed|alternative);.+boundary="(.+?)"$/s) {
+	 my @parts = split($1,(join "\n",$article->body()));
+	 for my $part (@parts) {
+	     if ($part =~ /^\r?\n?Content-Type: (image|video|audio|application|text\/html)/) {
+		 $score = $self->{'config'}->{'attachmentscore'};
+		 last;
+	     }
+	 }
+     }
+     $article->add_headers('X-Attachment-Test',$score);
+     return $score;
+ }
+
+
+sub spamfilter_language {
+    my ($self,$article) = @_;
+    my $guesser = Text::Language::Guess->new(languages => ['en',$self->{'config'}->{'lang'}]);
+    my @messagebody = $article->body();
+    my $score = 0;
+    my $lang = $guesser->language_guess_string(join "\n",@messagebody);
+    if (!defined($lang) or $lang ne $self->{'config'}->{'lang'}) {
+	$score = $self->{'config'}->{'langscore'};
+    }
+    $article->add_headers('X-Lang-Test',$score);
+    return $score;
+}
+    
+sub spamfilter_spamassassin {
+  my ($self,$article) = @_;
+  # use spamassassin
+  my $spamtest = Mail::SpamAssassin->new();
+  my @messageheader = $article->headers();
+  my @messagebody = $article->body();
+  my $header = join "\n",@messageheader;
+  my $body = join "\n",@messagebody;
+  my $status = $spamtest->check_message_text($header . $body);
+  my $score = $status->get_score();
+  $article->add_headers('X-Spamassassin-Test',$score);
+  return $score;
+}
+
+sub blacklist {
+   my ($self,$article) = @_;
+   return 1 if ($article->header('Newsgroups') =~ /de.admin.news.announce/);
+   return 1 if (defined($article->header('Newsgroups')) and 
+      $article->header('Newsgroups') !~ /$self->{'config'}->{'moderated_group'}/);
+   return 1 if (!defined($article->header('From')));
+   return 1 if (length($article->header('From')) < 2);
+   return 1 if ($article->bytes() > 100*1024);
+   # kaputte Postings
+   for my $headerline (qw(From Reply-To Subject Message-ID)) {
+       if (defined ($article->header($headerline)) and
+           length($article->header($headerline)) > 1019) {
+           return 1;
+        }
+    }
+   if (defined $self->{'config'}->{'blacklistfile'}) {
+     my $header = join "\n",$article->headers();
+     open(my $blacklistfile, $self->{'config'}->{'blacklistfile'}) or die $!;
+     while (<$blacklistfile>) {
+       chomp;
+       next if (length($_) <= 2);
+       if ($header =~ /$_/s) {
+         close $blacklistfile;
+         return 1;
+       }
+     }
+     close $blacklistfile;
+   }
+   return 0;
+}
+
+sub spamlearn {
+  my ($input,$isspam) = @_;
+  return;
+#  my $message = Mail::SpamAssassin::Message->new({'message' => $input});
+#  my $spamtest = new Mail::SpamAssassin ({
+#    'rules_filename'      => '/etc/spamassassin.rules',
+#     'userprefs_filename'  => $ENV{'HOME'}. '/.spamassassin/user_prefs'
+#   });
+#  my $mail = $spamtest->parse($message);
+#  my $status = $spamtest->learn($mail,undef,$isspam,0);
+#  $status->finish();                                                                              
+  
+#  my $spamobj = Mail::SpamAssassin->new();
+#  print defined $spamobj,"\n";
+#  $spamobj->learn($message,undef,$isspam,0);
+}