That is not quite right. There are rules for transfer pricing, which applies to the extent that it is possible to identify which assets were part of transactions. If the funds are only entering Canada, the recipient company has to fill out form T1134 and indicate the foreign country and the specific activity in that country that generated the funds.
On the assumption of good faith, it is assumed that the real activity will be reported. Since there is no tax audit, however, people can answer those questions as they wish. As a result, funds can enter the country relatively easily. Since we cannot control something we do not see, this is where things get tricky. This can pose a major problem.