Both international law and the Supreme Court of Canada have made it very clear that if people are going to be detained in an administrative context, that is, if we're detaining people who have not been tried or convicted of anything at all, that detention needs to be narrowly targeted and needs to have close time limits.
Also, it needs to be regularly supervised by the courts. The current supervision schedule is a review at 48 hours, at 7 days, and at 30 days. The Supreme Court of Canada has intimated that if you adjust that review schedule so that you aren't reviewing detention regularly, you will probably run afoul of Canadian constitutional protections.
Another key thing to keep in mind at the front end is that Canada already has more stringent security detention provisions than many other countries, so we are already quite close to the line in terms of international legal breaches in this area.