Get yii2 session in magento

I am running a MLM website in Yii2 framework.

And I have also a Magento shopping website in the same domain i.e.

Now I want to use the user session of Yii2 in Magento so that the user logged-in in Yii will be logged-in in Magento. I searched a lot in google but I did not get anything from there.

Please give me an Idea to start from.

I have also posted this in SO