[Dovecot] deliver rejection bounces

[Seth Mattinen]

Steffen Kaiser wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
> 
> On Sun, 18 Jan 2009, Seth Mattinen wrote:
> 
>> As a mail admin, I never want to see deliver generating its own 
>> messages to potentially forged addresses and spamming innocent people. 
>> The MTA should do this during the SMTP transaction.
> 
> Which MTA tries to deliver the mail during the SMTP dialogue?
> Neither Postfix nor sendmail does, unfortunately. Well, one would open 
> yet another can of worms, if doing so, I guess.
> 

Postfix. Will it do it out of the box? No. You can add hooks to Postfix 
using the pre-queue content filter, milter, access policy delegation or 
patches so that it can respond with a defer/reject during the SMTP session.

http://www.postfix.org/SMTPD_PROXY_README.html
http://www.postfix.org/MILTER_README.html
http://www.postfix.org/SMTPD_POLICY_README.html

I'm sure there are tools out there developed to take advantage of these 
interfaces that do what I'm alluding to, but I don't know any off the 
top of my head and I can't share mine.

~Seth