Blockchain access control method and device based on ciphertext policy attribute encryption

Abstract

The invention discloses a blockchain access control method and device based on ciphertext policy attribute encryption, solves the problems of data privacy disclosure, low throughput and the like caused by public transparency, block capacity limitation and the like of a block chain in the prior art, and enhances the controllability, privacy and expandability of data fusion and sharing. The method comprises the following steps: designing an access strategy of a tree logic structure according to an attribute set and an access demand; associating the ciphertext with an access strategy, and encrypting the data by using the access strategy to obtain the ciphertext; associating the key with the attribute set, and obtaining the key according to the attribute set; releasing the storage address of the ciphertext to a block chain network in a transaction form; and the user who satisfies the specified attribute set in the access strategy can obtain the secret key, and decrypts the stored ciphertext through the storage address on the block chain. According to the method, the credibility of the shared data is enhanced through the characteristics of non-tampering and public transparency of the block chain, the privacy and controllability of the data are guaranteed through ciphertext policy attribute encryption, and the expandability of the device is improved through the ciphertext storage address chaining. According to the method, the storage address of the data is encrypted through the access strategy instead of the access strategy or the encrypted data, so that the requirements of goodprivacy, high controllability, high throughput and the like can be met.

Description

technical field [0001] The present invention relates to the technical field of block chains, in particular to a block chain access control method and device based on ciphertext policy attribute encryption. Background technique [0002] At present, affected by various factors such as interests, privacy, and technical limitations, it is difficult for data owners to share the data they own, thus forming a "data island", which greatly hinders the maximization of data economic value. [0003] The distributed structure, transparency and trustworthiness, and immutable information of the blockchain provide the possibility to solve the data island. Using the blockchain to build a data sharing platform can realize trusted data exchange without relying on the credit endorsement of the third-party data sharing platform. [0004] However, privacy leakage has become a major obstacle to the application of blockchain-based data sharing platforms. As an important technical means to ensure ...

AI Technical Summary

Problems solved by technology

However, the openness and transparency of the blockchain makes access control policies exploitable by attackers, posing a great threat to data privacy.

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