How to add auth-check to an enhanced Infotype?

Greetings SCN .

I been working as a SAP ABAP HCM consultant for a while and sometimes client user Surprised me with their requirements, like this one:

To contextualize the problem:  I enhanced Infotype 8 with a subscreen with two new fields, in PM01 transaction.

The user asked me to include a validation (auth-check) to a role id to avoid some user to see thoses fields in the PA30 transactión.

I would like to Know how to proceed and where to add this auth-check.

Thanks you.