configuration files for access control settings

Schooltool 2.4.0:

In the documentation I read:

"Note that all the access control settings within the system can be modified from configuration files within SchoolTool’s source code. This is not a trivial matter, but extensive customization for specific sites is possible."

I understand that you changed the security settings a lot between schoolbell and schooltool (that's not a bad idea), but I didn't find any further info where to start.

I want teachers to be able to read the persons page of everybody.
It's clear that I have to recompile, but a hint where to search in the sources would be very time saving!

Thank you in advance!

Gerhard Schneider