In Indonesia, it's called Ketupat. It always available during Eid Al-Fitr in Indonesia. Usually used to eat together with soup foods, usually has coconut cream.

The origin of this thing has two versions : It's from age of Sunan Kalijaga and It's from age of Hindu-Buddha (older than age of Sunan Kalijaga)

The reference :
http://travel.kompas.com/read/2017/06/25/130900327/ini.asal.usul.ketupat.hidangan.khas.lebaran