That's another good use of it. I don't whitelist at the mail server level so I didn't think of it. As for punishing people with bad setups. Yes! Admins are already punished for running open relays, not having reverse DNS records, firewall blocking their sending SMTP servers and many other things. If they publish a SPF record, it had better be correct.
Copyright © 2017, Eklektix, Inc.
Comments and public postings are copyrighted by their creators.
Linux is a registered trademark of Linus Torvalds