DOAS: Efficient data owner authorized search over encrypted cloud data

Data outsourcing service can shift the local data storage and maintenance to cloud service provider (CSP) to ease the burden from data owner, but it brings the data security threats as CSP is always considered to honest-but-curious. Therefore, searchable encryption (SE) technique which allows cloud clients (including data owner and data user) to securely search over ciphertext through keywords and selectively retrieve files of interest is of prime importance. However, in practice, data user’s access permission always dynamically varies with data owner’s preferences. Moreover, existing SE schemes which are based on attribute-based encryption (ABE) incur heavy computational burden through attribution revocation and policy updating. To allow data owner to flexibly grant access permissions, we design a secure cryptographic primitive called as efficient data owner authorized search over encrypted data scheme through utilizing identity-based encryption (IBE) technique. The formal security analysis proves that our scheme is secure against chosen-plaintext attack (CPA) and chosen-keyword attack (CKA) without random oracle. Besides, empirical experiments over real-world dataset show that our scheme is efficient and feasible with regard to data access control.