Given the rapid development of cloud computing and cloud storage technology, a growing number of enterprises and individuals use cloud storage services to save data or back up data. In the cloud storage services, although attribute-based encryption can protect users’ data security, the computational cost of key generation, data encryption, and data decryption linearly increases with the complexity of access strategies, which becomes more critical for resource-constrained users. Therefore, this paper proposes a verifiable attribute-based encryption scheme for a fully outsourced ciphertext policy. The scheme can simultaneously realize the functions of key generation, data encryption, and data decryption outsourcing and verify the correctness of the outsourcing calculation results. This scheme can effectively reduce the computational burden of a cloud storage system. The security and verifiability of the scheme are indicated and proved with the random oracle model. The experimental results show that the scheme has the advantages of function and efficiency compared with other schemes. The research results have theoretical and practical significance.

With the continuous development of mobile applications and location technology, k -anonymity technology is usually used to protect the privacy and security of users in location-based services that are used by mobile users. Due to the self-interest of users, in the cooperative construction of a k -anonymity privacy protection scheme, it is difficult to guarantee the honest cooperation behavior of the requesting and cooperating users. To solve the above problems, this paper proposes a distributed k -anonymous location privacy protection scheme based on blockchain. In this paper, we record the requesting users, cooperative users, and their location information as evidence, and we punish the users with location leakage and deception. An anonymous zone cannot be constructed when the user is a requesting user. An interactive record mechanism is designed to constrain the self-interest behavior of the requesting and cooperating users in the process of anonymous region construction. Security analysis and experiments show that this scheme can effectively protect the user’s location privacy, promote the honest cooperation between the requesting user and the cooperative user, and encourage more users to participate in the construction of an anonymous zone.