It's possible that you will not legally be entering Canada. You should really check with your airline on this, as this is an unusual arrangement. If indeed you are just stopping in Canada and not disembarking, it is entirely possible that you will not need to clear Canadian customs and immigration. There have been flights in the past, e.g. from Asia to the US via Vancouver, which functioned this way. The plane stopped at Vancouver International Airport, dropped off the Vancouver-bound passengers (who did clear Canadian customs and immigration), and continued on to the US without taking on any new passengers.
What airline and flight are you taking, and what is the originating airport?