Format to whitelist a domain?

Format to whitelist a domain?

Hi!

I want to add a domain to my whitelist, i.e., I want to whitelist alice@whatever.com, bob@whatever.com, and anyone else sending from an email address in the domain of whatever.com.

Do I type in *@whatever.com, or whatever.com, or @whatever.com?

I know that a similar question was asked three years ago, but I didn't understand the answer.

Thanks.
D.