Best way to drop an outbound email

[lnedry]

What is the best way to drop an outbound email?

Once in a while a web hosted customer will configure a contact us form that sends an email with a From domain that isn't hosted here. I tried DENYDISCONNECT in the hook_data_post but the email reject message gets sent to the From address.

[msimerson]

• A1: Off the top of my head, create a plugin that listens on queue and queue_outbound and returns OK for messages that match your criteria.
• A2: In feat: if AUTH, assure Env From dom matches AUTH dom #3265, I have implemented a check that requires the Envelope Sender domain to match the domain used during SMTP AUTH. Use a test like that to prevent emails from non-local domains being accepted in the first place.