How can I tell exim to block all TLDs not in my list?

[IT_Architect]

How can I tell exim to block all TLDs not in my list?

Spammers buy a new domain every second and come up with 100 new users for that domain every half second. Now they do the same with TLDs. SpamAssassin's Bayes is working well now, but that results in piles of junk in the spam folder to look through that end in .win, .club, .accounting, etc. These TLDs make money for the people selling them and spammers, but nobody else. Any legit business would have to be ignorant to buy a domain from them. I want to set up a list of domains I allow IN, not a list of domains to keep out that changes by the minute. That way there will be a lot fewer spam messages for people to look through.

Thanks!