Harakiri:
> I know about all the difficulties with MX lookup etc, the original
> goal would be - that i have a policy for external domains - and
> that for certain domains a message should only be sent if TLS is
> available - if a message to a certain domain is sent which does
> not support TLS - it should be blocked - i know i could probably
In that case, everything you need already exists.
1) Configure the Postfix SMTP client to REQUIRE TLS.
smtp_tls_security_level=encrypt
2) Configure the Postfix SMTP server to reject mail that
cannot be delivered via SMTP-over-TLS.
smtpd_recipient_restrictions =
reject_unverified_recipient
permit_mynetworks
reject_unauth_destination
See also:
http://www.postfix.org/ADDRESS_VERIFICATION_README.html#recipient
http://www.postfix.org/ADDRESS_VERIFICATION_README.html#caching
Wietse
