Ok... so... The smell of "fresh" marijuana (not burnt) provides officers reasonable grounds to believe someone is in possession of marijuana, ie, there IS marijuana in the car and/or on the person(s). Reasonable grounds is not 100% certainty. One can argue being in possession if only burnt marijuana is smelled, but fresh is very distinct. Once RGs are established the officer may arrest and search subsequent to arrest.
Something is either legal or not legal in terms of the Criminal Code, there isn't "basically legal". I bet you think those marijuana dispensaries in Vancouver are all legal, and that those membership card they give you are legal documentation allowing you to be in possession of marijuana, don't cha?