Re: Reject messages from spoofed addresses except ones coming from specifc hosts? [SPF]



"Gross, Michael" <michael.gross@xxxxxx> wrote:
is it possible to configure sendmail so that messages from a
particular domain are rejected except when those are coming from
particular hosts?

For instance: Reject every message with sender address spoof.com when
coming from unspecified hosts, but allow messages from spoof.com when
they are received from i.e. server 12.12.12.12?

Is this easily possible in sendmail (version is 8.13.8).

Have you considered configuring support for SPF records in DNS?
http://www.openspf.org/
SPF allows DNS domain owner to list host allowed to use it in email.
It allows sites supporting SPF to reject messages with envelope sender
not in fitting SPF list.

AFAIK SPF support can be implemented via milters e.g. via multipurpose
(free) http://MIMEDefang.org/ milter.

--
[pl>en Andrew] Andrzej Adam Filip : anfi@xxxxxxx : anfi@xxxxxxxx
Open-Sendmail: http://open-sendmail.sourceforge.net/
What is research but a blind date with knowledge?
-- Will Harvey
.