For everyone who are arguing over the topic. I am just adding all the facts here, there's nothing new in my post.
Only Gazi TV holds the right for All Bangladesh hosted matches till 2020, just as like Star in India. Gazi TV is selling the property to different international territories in series based method. One channel might buy all the matches till 2020 if they are interested from Gazi TV.
We've seen contradictory evidence regarding Star Sports on Bangladesh rights. Some pakistani sources claimed that SS has the Indian license to show Bangladesh matches until 2020 which is never officially announced by Gazi TV or Star Sports.
So at this moment it's safe to assume Star is buying the match rights in series by series method from Gazi TV. Bangladesh have played 4 home series in last one year. Excluding Zim tour all the tours are broadcasted by SS in India. No broadcasters have shown that series in India.