Biblio

In previous multi-authority key-policy attribute-based Encryption (KP-ABE) schemes, either a super power central authority (CA) exists, or multiple attribute authorities (AAs) must collaborate in initializing the system. In addition, those schemes are proved security in the selective model. In this paper, we propose a new fully secure decentralized KP-ABE scheme, where no CA exists and there is no cooperation between any AAs. To become an AA, a participant needs to create and publish its public parameters. All the user's private keys will be linked with his unique global identifier (GID). The proposed scheme supports any monotonic access structure which can be expressed by a linear secret sharing scheme (LSSS). We prove the full security of our scheme in the standard model. Our scheme is also secure against at most F-1 AAs corruption, where F is the number of AAs in the system. The efficiency of our scheme is almost as well as that of the underlying fully secure single-authority KP-ABE system.

With the rapid development of mobile internet, mobile devices are requiring more complex authorization policy to ensure an secure access control on mobile data. However mobiles have limited resources (computing, storage, etc.) and are not suitable to execute complex operations. Cloud computing is an increasingly popular paradigm for accessing powerful computing resources. Intuitively we can solve that problem by moving the complex access control process to the cloud and implement a fine-grained access control relying on the powerful cloud. However the cloud computation may not be trusted, a crucial problem is how to verify the correctness of such computations. In this paper, we proposed a public verifiable cloud access control scheme based on Parno's public verifiable computation protocol. For the first time, we proposed the conception and concrete construction of verifiable cloud access control. Specifically, we firstly design a user private key revocable Key Policy Attribute Based Encryption (KP-ABE) scheme with non-monotonic access structure, which can be combined with the XACML policy perfectly. Secondly we convert the XACML policy into the access structure of KP-ABE. Finally we construct a security provable public verifiable cloud access control scheme based on the KP-ABE scheme we designed.