On Tue, 12 Jun 2001, Phil Chambers wrote:
> My previous message leads me to ask about filtering being handled differently. At
> present the SMTP phase is completed before the filter is run. That means that any
> rejection caused by the filter can only be returned to the sender if the sender is
> not spoofed. These days "MAIL FROM: <>" seems to be the standard means of sending
> out viruses, so it is MAILER-DAEMON at the receiving site which gets them all.
>
> Exim provides for the header recipient and sender fields to be checked during the
> SMTP data phase and produce a 550 response at the end. It would be nice if system
> filters could be run during this phase too. That way the problem of sorting out
> bounced messages would remain with the sending site, not the receiving site.
>
> Any chance of such a change for Exim 4?
Expanding what can be checked at SMTP time is something that I'm working
on for Exim 4. I don't think it will include full filter running. It
will, however, include more general expansion checking - after the DATA
phase, for example, $message_body will be accessible.
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.