Ciphertext policy attribute-based encryption system and method

Abstract

The invention provides a ciphertext policy attribute-based encryption system and a ciphertext policy attribute-based encryption method, which comprise ciphertext policy attribute-based encryption systems with a central mechanism and without the central mechanism and a ciphertext policy attribute-based encryption method. The ciphertext policy attribute-based encryption system with the central mechanism comprises a plurality of attribute mechanisms of the central mechanism, an encrypting component and a client. The plurality of attribute mechanisms of the central mechanism initialize the system together, publish a system public key, and generate a system private key, a local private keys of an attribute mechanism and local public keys; the encrypting component encrypts a cleartext based on the system public key, each local public key and a universal access tree; and the client inputs a client identifier, client attribute sets and the like so as to generate client private key used for decrypting the encrypted ciphertext. Due to the implementing mode of the invention, a multi-mechanism ciphertext policy attribute-based encryption system is designed. The scheme is based on the ciphertext policy, so the scheme better meets the access control requirement in an actual information safety system.

Description

technical field [0001] The invention relates to a ciphertext policy attribute-based encryption system and an encryption method thereof, in particular to a ciphertext policy attribute-based encryption system including a plurality of attribute institutions with or without a central authority and an encryption method thereof. Background technique [0002] The attribute-based encryption scheme was first proposed by Vipul Goyal, Omkant Pandey, Amit Sahai and Brent [0003] Waters [1] propose. Early attribute-based encryption schemes were mainly private-key-policy, meaning that the ciphertext reflected the set of attributes and the private key represented the access control policy. [0004] figure 1 is a schematic diagram illustrating a private key distribution system of an attribute encryption scheme according to a prior art private key policy. Such as figure 1 As shown, the private key distribution system includes a private key distribution organization 10 and two confident...

AI Technical Summary

Problems solved by technology

However, the disadvantage of this scheme is that there is only one private key distribution organization

This means: First, since a single private key distribution agency needs to be responsible for the distribution of all private keys and the corresponding attribute verification work for customers, the communication and computing costs of the private key distribution agency are relatively high, and the workload is heavy

In addition, if the private key distribution organization is controlled by an attacker, the entire system will have no security performance at all

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