[Mimedefang] questions about filter parsing, message mod'ing, and bouncing messages

[David F. Skoll]

TLD MimeDefang wrote:

> First, if filter() is called on a message, is it possible that
> filter_multipart() will also be called?

Sure.

> I have moved the spamassassin checking into the filter() and
> filter_multipart() sections,

Don't do that.

filter() is called once for each leaf MIME-part, and filter_multipart()
is called once for each non-leaf MIME part.

Keep your SA tests in filter_begin or filter_end.

> Next, I have a number of rules in the different filter subs that
> cause message rejection/bounces.  I found quickly that the message
> for action_bounce() must be fairly short.  What I really want to
> do is to include more information in the bounced message, so that
> legitimate users can see why the message was rejected.

MIMEDefang does not currently support multiline replies (it's on the
TODO list.)  There's also no guarantee end-users will see the text;
some MTAs eat it.

> So, I figured I could use the action_notify_sender() to do this,

Don't do that.  You'll be blacklisted for generating backscatter within
hours.

Regards,

David.