How to check if point is inside collider?

I want to know if a point is inside a collider. OnMouseOver is no option for me because the collider is not always in the front and I want to call it like this:

  if(pointIsInCollider(collider, point))
    {
        //do stuff...
    }

So if the green rectangle is my collider, pointIsInCollider returns true for my red point and false for my blue point.

Use Collider2D.OverlapPoint.