Verifiable mobile online social network privacy-preserving location sharing scheme

摘要

With the dramatic growth of smart phones and social network services, location-based servicernhas become increasingly popular in our daily life, which also brings great privacy leakage aboutrnuser's location information. Thus, privacy-preserving location sharing is still a significant problem.rnIn this paper, two models of our scheme are verifiable, supporting location query on homomorphicrnencrypted ciphertext with searching index and trapdoor. The characteristics of our schemernare that it (1) allows users to share their current location without leaking any location informationrnto the untrusted server; (2) protects users from the cheating of untrusted server'smaliciousrnbehavior by verifying query resu (3) supports a novel personalized query according to users'rnclassifications of social network friends; (4) the user does not have to be online to make permissionsrnfor accessing his shared location, and (5) model 2 does not rely on any trusted third partyrnserver to perform any computation. The security analysis shows that it ensures secure locationrnsharing in social scenarios.