Cipher Text-Policy Attribute-Based Encryption...

Cipher Text-Policy Attribute-Based Encryption: An Expressive, Efficient, and Provably Secure Realization

Author Name : Sarvade Sreedeepthi, T. Baba

ABSTRACT : In the cloud, for achieving access control and keeping data confidential, the data owners could adopt attribute-based encryption to encrypt the stored data. Users with limited computing power are however more likely to delegate the mask of the decryption task to the cloud servers to reduce the computing cost. As a result, attribute-based encryption with delegation emerges. Still, there are caveats and questions remaining in the previous relevant works. For instance, during the delegation, the cloud servers could tamper or replace the delegated cipher text and respond a forged computing result with malicious intent. They may also cheat the eligible users by responding them that they are ineligible for the purpose of cost saving. Furthermore, during the encryption, the access policies may not be flexible enough as well. Since policy for general circuits enables to achieve the strongest form of access control, a construction for realizing Attribute-based hybrid encryption with verifiable delegation using circuit cipher-text policy has been considered in our work. In such a system, combined with verifiable computation and encrypt-then-Mac mechanism, the data confidentiality, the fine-grained access control and the correctness of the delegated computing results are well guaranteed at the same time. Besides, our scheme achieves security against chosen-plaintext attacks under the k-multi linear Decisional Diffie-Hellman assumption. Moreover, an extensive stimulation campaign confirms the feasibility and efficiency of the proposed solution. The scope of main project is to view or upload the data in cloud server for only authorized persons.