Stephen Satchell:
> That said, if you don't want to expose the reason for the rejection,
> PostFix gives you that ability, although not necessarily the way that
> you want it. The way to do that is to write a policy filter that will
> detect the problems, and return status to PostFix to say "reject this
> mail for policy reasons" without being specific. If this is important
> to you, you will go to the effort.
Specifically, if you can reply "action=reject" in smtpd_data_restrictions,
then messages will be blocked with;
554 5.7.1 <DATA>: Data command rejected: Access denied
For this the policy service client needs to maintain one flag per
session handle. Raise the flag when the client, helo, sender or
recipient are unacceptable.
Wietse
> The policy filter isn't hard to write; I did the initial version in Perl
> in a couple of hours. As I gained more experience, I put in additional
> features. The reason I did the extra work was that my customers had
> varying requirements for mail delivery, so the policy filter customized
> the checking/blocking for each domain, and in some instances by specific
> mail addresses.
