On the first part, I'll refer to the Immigration and Refugee Protection Act, where in section 39 it talks about what we call an inadmissibility criteria. Someone is inadmissible for financial reasons if they are unable or unwilling to support themselves or any other person who is dependent on them and have not satisfied a visa officer that adequate arrangements for care and support, other than those that involve social assistance, have been named. That's the condition in the legislation as it currently stands with respect to the kinds of support and undertakings that a foreign national—a temporary foreign worker, an international student, or a visitor—has to have to be admissible to Canada.
On November 17th, 2014. See this statement in context.