The type 17 ship launched Anti Ship Missile is based on the Vertical Launch type 12 land based anti-ship missile which originated from the air launched anti ship missile ASM-1.
Like the type 12 land based ASM, the type 17 Ship launched ASM is capable of vertical launch and equipped with GPS for mid-flight target acquisition feature.
If you look at the diagram closely you'll able to follow the progression of how the missile evolved with the top layer representing Air launched version, the middle layer representing the land based version and the bottom layer representing the ship launched version.