Efficient Predicate Encryption Supporting Construction of Fine-Grained Searchable Encryption

Predicate Encryption (PE) is a new encryption paradigm which provides more sophisticated and flexible functionality. PE is sufficient for some new applications, such as fine-grained control over access to encrypted data or search on encrypted data. We present an efficient construction of predicate encryption which is IND-AH-CPA secure by employing the dual system encryption without random oracle. We clarify the relations between PE and Searchable Encryption in detail. The new notion of Public-Key Encryption with Fine-grained Keyword Search (PEFKS) is proposed. We prove that a IND-AH-CPA secure PE scheme implies the existence of a IND-PEFKS-CPA secure PEFKS scheme. We develop the transformation of PE-2-PEFKS and use the transformation to construct an efficient PEFKS scheme from our new PE scheme. We believe our results will be useful to guide a final good result.