* plugins/check_basicheaders

Refuse messages that lack basic headers per RFC-2822
     (Jim Winstead)
     modified by John Peacock to block null messages, too


git-svn-id: https://svn.perl.org/qpsmtpd/trunk@333 958fd67b-6ff1-0310-b445-bb7760255be9

plugins/check_basicheaders

@@ -0,0 +1,71 @@
+#!/usr/bin/perl
+
+=head1 NAME
+
+check_basicheaders - Make sure both From and Date headers are present, and
+do optional range checking on the Date header
+
+=head1 DESCRIPTION
+
+Rejects messages that do not have a From or Date header or are completely 
+empty.
+
+Can also reject messages where the date in the Date header is more than
+some number of the days in the past or future.
+
+=head1 CONFIGURATION
+
+Takes one optional parameter, the number of days in the future or past
+beyond which to reject messages. (The default is to not reject messages
+based on the date.)
+
+=head1 AUTHOR
+
+Written by Jim Winstead Jr.
+
+=head1 LICENSE
+
+Released to the public domain, 26 March 2004.
+
+=cut
+
+use Date::Parse qw(str2time);
+
+sub register {
+  my ($self, $qp, @args) = @_;
+  $self->register_hook("data_post", "check_basic_headers");
+
+  if (@args > 0) {
+    $self->{_days} = $args[0];
+    $self->log(1, "WARNING: Ignoring additional arguments.") if (@args > 1);
+  }
+}
+
+sub check_basic_headers {
+  my ($self, $transaction) = @_;
+
+  return (DENY, "You have to send some data first")
+    if $transaction->body_size == 0;
+
+  return (DENY, "Mail with no From header not accepted here")
+    unless $transaction->header->get('From');
+
+  my $date = $transaction->header->get('Date');
+
+  return (DENY, "Mail with no Date header not accepted here")
+    unless $date;
+
+  return (DECLINED) unless defined $self->{_days};
+
+  my $ts = str2time($date);
+
+  return (DECLINED) unless $ts;
+
+  return (DENY, "The Date in the header was too far in the past")
+    if $ts < time - ($self->{_days}*24*3600);
+
+  return (DENY, "The Date in the header was too far in the future")
+    if $ts > time + ($self->{_days}*24*3600);
+
+  return (DECLINED);
+}