Letting email sending only from authorized IPs?

Remitur

Active Member
Jan 17, 2018
32
2
8
Ljubljana
cPanel Access Level
Root Administrator
Hello.

I would like to configure cPanel's SMTP service such that an user can send email(s) only if it's connected from certain(s) IP.

That's to say: a user (real or virtual) who is connecting from a whitelisted IP, can send email, even without username/password authentication.

If he's connecting from elsewhere, instead, usual username/password authentication is required.
Is it somewhat possible???