Hello, I would like to progressively restrict the ability for users to impersonate other email addresses when they use our authenticated SMTP (Postfix + Dovecot). We have about 2500 users on this SMTP server but we have about 50K total users and 60K email adresses. As a first step I would like to setup a diagnostic to find out who is sending emails that would violate a given smtpd_sender_login_maps, without triggering a true Reject. A line in the log file would be great.
Is that possible? Thanks, Patrick
