Unless you're going to be a commuter, you don't really need to worry about parking at Canisius. The Metro system and the Buffalo CarShare program basically eliminate the need to have a car yourself.
But if you do bring a car to campus, you'll always find parking in the ramp on Jefferson, and there are also quite frequently spaces open near the Koessler Athletic Center (KAC). Don't bother to try and find street parking right next to campus—it will be a futile effort. You do need a parking permit for the ramp and any other lots on campus. Public Safety checks and will give you a warning or a ticket if you lack a permit. Certain permits are only allowed to park in designated areas. However, all lots are available to all permits from 4 p.m. to 7 a.m.