[Pymilter] postfix, pysrs and smfi_chgfrom

[Stuart D. Gathman]

The existing pysrs package installs a sendmail CF macro that routes the 
envelope sender through a socketmap for *outgoing* connections.  This 
allows disabling SRS for selected (broken) mail relays.  (Some braindead spam 
filters think that a '+' in the localpart indicates spam.)

The new chgfrom milter mutator can be called from the eom callback for an
*incoming* connection.  So if some of the recipients are SRS, and some are
NOSRS, then we have to duplicate the message - or SRS all, or NOSRS all.

The consequences of NOSRS is that we reject any DSNs resulting from that
message.  The consequences of SRS is that the broken MXes will reject
the message.

So it looks like a milter cannot actually replace pysrs.  Am I missing
something?

So the best I can do for the postfix people is to create an srsmilter
that does srs/sign/ses or not based solely on MAIL FROM.  I suppose
it could look at recipients also, and do the right thing in many cases
(single recipients or all of one type), with an option to do all SRS or all
NOSRS for mixed recipients.

While the existing pysrs package bases NOSRS on the *relay*, I suppose
it is useful to base it on the RCPT domain instead for an srsmilter.

-- 
	      Stuart D. Gathman <stuart at bmsi.com>
    Business Management Systems Inc.  Phone: 703 591-0911 Fax: 703 591-6154
"Confutatis maledictis, flammis acribus addictis" - background song for
a Microsoft sponsored "Where do you want to go from here?" commercial.