On Wed, 27 Apr 2005, Jason Keltz wrote:
> Hi Philip,
>
> I've looked into redirect routers, but not sure if they can do what I'm
> looking for - namely, call spamc once per recipient, AS each recipient (so
> their settings get used) on the incoming message, and then deliver the scanned
> copy of the e-mail rather than the original email to the recipients. If you
> can suggest how I might do this, this would be very helpful.
A redirect router can certainly arrange to deliver the message to spamc
as the recipient, for each recipient. (This is just like piping a
message to a list handler such as majordomo or listman.)
However, you'll have to re-inject the message afterwards, in order to
get it delivered. This will be harder, because you have to make a
scanned message recognizable to Exim, and if spamc is running as the end
recipient, it won't be able to set the protocol option (-oMr) that is
normally used to indicate this in a secure way. You could use a special
header, provided you make sure that incoming messages do not have that
header - you could remove it in a system filter.
This kind of thing is the way people used to run SpamAssassin before Tom
implemented the ACL interface. It costs two passes through Exim, and
also it means you have accepted the message before scanning it.
You can even run spamc as a transport filter using BSMTP to operate in
this manner. There is an example of this on pages 163-164 of the Exim 4
book.
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.
Get the Exim 4 book: http://www.uit.co.uk/exim-book
