Multi-authorization attribute-based encryption method and system without key escrow

Abstract

The invention discloses a multi-authorization attribute-based encryption method and system without key escrow, and the system comprises a user identity manager (IDM), an attribute authorization center(AAs), a data owner (DO), a data user (DU), and a cloud storage server (CSS). The method comprises the steps that the DU submits the legal identity information and commitment value of the DU to the IDM; after successfully detecting the identity of the DU, the IDM generates and returns a corresponding certificate containing the DU commitment value; when applying for a decryption key to the AAs, the DU is required to submit a corresponding commitment value; after successfully verifying the signature in the certificate, the AAs calculates a corresponding private key for the DU; the DO encryptsthe data and uploads the encrypted data to the CSS; and the DU downloads the corresponding ciphertext from the CSS and decrypts the ciphertext by using the private key of the DU. According to the method, the secret value of the embedded user is increased, the private key value of the legality authentication role is embedded and the like, so that the problem of key escrow is solved, and the problems of AAs collusion attack resistance and malicious user collusion attack resistance are also solved.

Description

technical field [0001] The invention relates to the technical field of cloud computing security, in particular to a multi-authorization attribute-based encryption method and system without key trusteeship. Background technique [0002] An important application of cloud computing services is data storage, where data owners upload data to the cloud for some special users. In order for those users to use that data, they must first obtain data access permissions. Data owners and data consumers do not interact directly. In order to protect the data confidentiality of data owners, many data encryption and data access control methods are adopted to prevent data resources from being used by unauthorized users. In a complex cloud computing environment, cloud servers are often manipulated by commercial organizations, which may provide data access to unauthorized users for some benefit. Therefore, based on the fact that those servers may not be able to obtain an effective security m...

AI Technical Summary

Problems solved by technology

Therefore, based on those servers may not be able to obtain an effective security mechanism, data owners cannot fully trust cloud servers to provide secure data access management

In attribute-based encryption (ABE) applications, the attribute authorization center AAs can generate the decryption key of all users, and can decrypt the ciphertext of all users without user participation, that is, there is a key escrow problem

Images