Attribute-based encryption with location verification and policy adjusting supporting the cloud mobile office

Facing the problems of the users' location privacy leakage and the indirect adjusting policies of the ciphertext stored in the cloud, in a mobile officie environment with cloud, a Ciphertext-Policy Attribute-Based Encryption with the Location Verification and Policy Adjusting (LVPA-CP-ABE) scheme is proposed. In the scheme, we apply BGV (Brakerski-Gentry-Vaikuntanathan) homomorphic encryption to protect the users' location privacy and updating key generated by the data owner directly to adjust the policy of the ciphertext stored in the cloud in the meantime. Moreover, in consideration of the endurance of mobile devices, the idea of outsourcing the BGV computation and BGV decryption as well as the ciphertext adjusting part is also introduced. The simulation indicates that our scheme is highly efficient in terms of users' computational cost.