Support attribute anonymous multiauthority access control scheme

Spurred by the rapid development of the Internet of Things, data sharing has also risen. However, in this process, the protection of sensitive information has not attracted enough attention, and the leakage of user privacy has emerged one after another. Attribute-based encryption of multi-authority ciphertext policy is an important means to protect ciphertext in the process of data sharing. However, in the key generation stage, malicious authorities collect user identity and attribute information through key generation, which causes huge dangers to privacy security. Therefore, this paper proposes supporting attribute anonymous multi-authority access control scheme SM9 signature. In the key generation stage, user attributes are divided into attribute values and attribute names. The authorities only have the polynomial coefficient of the attribute value set corresponding to the relevant attribute name, but it knows nothing about the specific at-tribute value. At the same time, the user does not know the attribute value that satisfies the policy. After safety proof and performance analysis, this scheme is efficient and safe.