  This paper presents a secure communication application called
DiscoverFriends. Its purpose is to securely communicate to a group of online
friends while bypassing their respective social networking servers under a
mobile ad hoc network environment. DiscoverFriends leverages Bloom filters and
a hybrid encryption technique with a self-organized public-key management
scheme to securely identify friends and provide authentication. Additionally,
DiscoverFriends enables anonymous location check-ins by utilizing a new
cryptographic primitive called Function Secret Sharing. Finally, to the best of
our knowledge, DiscoverFriends implements and evaluates the first Android
multi-hop WiFi direct protocol using IPv6.
