[svn:qpsmtpd] r720 - contrib/vetinari

[veti...@cvs.perl.org]

Author: vetinari
Date: Sat Mar 3 03:54:36 2007
New Revision: 720

Added:
contrib/vetinari/header_filter

Log:
header_filter plugin added

Added: contrib/vetinari/header_filter
==============================================================================
--- (empty file)
+++ contrib/vetinari/header_filter Sat Mar 3 03:54:36 2007
@@ -0,0 +1,157 @@
+=head1 NAME
+
+header_filter - filter (drop) mails based on certain header fields
+
+=head1 DESCRIPTION
+
+The B<header_filter> can drop mails just by some header fields. This was
+written to drop mails by known spam I<Subject:>s, but may be used to drop
+mails by any header fields.
+
+=head1 CONFIG
+
+The plugin uses the I<header_filter> config file. This file contains lines
+with four (or three) fields, separated by white space.
+The first field is the name of the header to look at, the second field either
+a string or a perl regex surrounded by ``/''. Both (string/regex) are of
+course without any spaces inside. If you need spaces, use a regex with I<\s>
+or I<\x20>. Before matching any I<\t> (TAB), I<\r> (CR) and I<\n> (LF) are
+replaced by a space (" "). Strings are compared case sensitive, regexes
+case insensitive.
+
+Any $RCPT, $RCPT_HOST, $RCPT_USER in a regexp will be replaced by the first
+recipient's address, host part of address, local part of address. Same for
+$FROM, $FROM_HOST, $FROM_USER.
+
+
+The third field is a (valid) return constant from Qpsmtpd::Constants. Lines
+with invalid constants are ignored and B<OK> or B<DONE> are mapped to
+B<DECLINED>.
+
+The last optional field (which may contain spaces) is the message which is
+returned with the constant to qpsmtpd if the regex (or string) matches.
+
+=head1 EXAMPLE
+
+ Subject /^Re:(\s*\d+)?\s+V\S*A\S*GH?RA\s*$/ DENY Spam... detected
+ Subject /^(It's\s+\S+|\S+\s+here)\s+\:\)\s*$/ DENY Spam... detected
+ Subject Hi DENY Spam... detected
+ ## only use if you're the only MX for $RCPT_HOST and your hostname is
+ ## not $RCPT_HOST!
+ Received /^from.*by\s+$RCPT_HOST\s+with\s+esmtp.*for\s+$RCPT\s*;/ DENY Spam
+
+=cut
+
+use Qpsmtpd::Constants;
+use Qpsmtpd::DSN;
+
+sub hook_data_post {
+ my ($self, $transaction) = @_;
+ my ($header, $re, $const, $comment, $str, $ok, $err);
+ my $line = 0;
+
+ my ($RCPT,$RCPT_HOST,$RCPT_USER,$FROM,$FROM_HOST,$FROM_USER);
+ my @rcpt = $self->transaction->recipients;
+ $RCPT_HOST = $rcpt[0]->host;
+ $RCPT_USER = $rcpt[0]->user;
+ $RCPT = $RCPT_USER .'@'. $RCPT_HOST;
+ $RCPT_HOST = quotemeta $RCPT_HOST;
+ $RCPT_USER = quotemeta $RCPT_USER;
+ $RCPT = quotemeta $RCPT;
+
+ my $from = $self->transaction->sender;
+ $FROM_HOST = $from->host || "";
+ $FROM_USER = $from->user || "";
+ $FROM = $FROM_USER .'@'. $FROM_HOST;
+ if ($FROM =~ /\@$/) {
+ $FROM = "<>";
+ }
+ $FROM_HOST = quotemeta $FROM_HOST;
+ $FROM_USER = quotemeta $FROM_USER;
+ $FROM = quotemeta $FROM;
+
+ foreach my $cfg ($self->qp->config("header_filter")) {
+ $cfg =~ s/^\s*//;
+ ($header, $re, $const, $comment) = split /\s+/, $cfg, 4;
+ ++$line;
+ $str = undef;
+
+ unless (defined $re) {
+ $self->log(LOGWARN, "header_filter - no regex/string in line $line");
+ next;
+ }
+ if ($re =~ m#^/(.*)/$#) {
+ $re = $1;
+
+ $re =~ s/\$FROM_HOST/$FROM_HOST/g;
+ $re =~ s/\$FROM_USER/$FROM_USER/g;
+ $re =~ s/\$FROM/$FROM/g;
+ $re =~ s/\$RCPT_HOST/$RCPT_HOST/g;
+ $re =~ s/\$RCPT_USER/$RCPT_USER/g;
+ $re =~ s/\$RCPT/$RCPT/g;
+
+ $ok = eval { $re = qr/$re/i; };
+ if ($@) {
+ ($err = $@) =~ s/\s*at \S+ line \d+\.\s*$//;
+ $self->log(LOGWARN, "REGEXP '$re' not valid (line $line): $err");
+ next;
+ }
+ # $self->log(LOGWARN, "RE='$re', OK='$ok'");
+ $re = $ok;
+ }
+ else {
+ $str = $re;
+ }
+
+ unless (defined $const) {
+ $self->log(LOGWARN, "header_filter - no return code in line $line");
+ next;
+ }
+
+ $ok = $const;
+ $const = Qpsmtpd::Constants::return_code($const);
+ unless (defined $const) {
+ $self->log(LOGWARN,
+ "header_filter - '$ok' is not a valid "
+ . "constant, ignoring line $line"
+ );
+ next;
+ }
+
+ foreach my $hdr ($transaction->header->get($header)) {
+ $hdr =~ s/[\r\n\t]+/ /sg;
+ $hdr =~ s/^\s*//;
+ if (defined $str) {
+ next unless $str eq $hdr;
+ $self->log(LOGDEBUG, "String $str from line $line "
+ ."matched header '$header: $hdr', "
+ ."returning $ok");
+ }
+ else {
+ next unless $hdr =~ $re;
+ $self->log(LOGDEBUG, "RE $re from line $line "
+ ."matched header '$header: $hdr', "
+ ."returning $ok");
+ }
+ if ($const == OK || $const == DECLINED || $const == DONE) {
+ return(DECLINED);
+ }
+ else {
+ return Qpsmtpd::DSN->media_unsupported($const,
+ ($comment || "Some header field denied"));
+ }
+ }
+ }
+ return (DECLINED);
+}
+
+=head1 COPYRIGHT AND LICENSE
+
+Copyright (c) 2006 Hanno Hecker
+
+This plugin is licensed under the same terms as the qpsmtpd package itself.
+Please see the LICENSE file included with qpsmtpd for details.
+
+=cut
+
+# vim: ts=4 sw=4 expandtab syn=perl