A BGN type outsourcing the decryption of CP-ABE ciphertexts

Abstract

Cloud computing security is the key bottleneck that restricts its development, and access control on the result of cloud computing is a hot spot of current research. Based on the somewhat homomorphic encryption BGN and combined with Green’s scheme that proposed outsourcing the decryption of CP-ABE (Ciphertext-Policy Attribute-Based Encryption) ciphertexts, we constructed a BGN type outsourcing the decryption of CP-ABE ciphertexts. In our construction, partial decryption of ciphertexts is outsourced to the cloud, and only users whose attribute meets the access policy will get the correct decryption. And the scheme supports arbitrary homomorphic additions and one homomorphic multiplication on ciphertexts. Finally, we prove its semantic security under the subgroup decision assumption and compare it with other schemes.