CCA secure proxy re-encryption method with delegable verifiability

Abstract

The invention provides a CCA secure proxy re-encryption method with delegable verifiability and is used for solving the problem that in the prior art, an encryption method is insufficient in security. The method comprises the realization steps that a data owner generates a system parameter and calculates own public key and private key; a data receiver calculates own public key and private key; the data owner carries out second-layer ciphertext encryption on a plaintext, uploads a result to a cloud server, moreover calculates a re-encryption key and sends the re-encryption key to the cloud server; the cloud server carries out composite encryption on a second-layer ciphertext, signs the result, moreover, calculates a signature verification key and sends the second-layer ciphertext, a public key encrypted ciphertext, a signature value and the signature verification key to the data receiver; the data receiver sends the received data and the public key encrypted private key to a client; the client carries out legality verification on the public key encrypted ciphertext; the client carries out integrity and legality verification on a re-encrypted ciphertext; and the data receiver decides whether to decrypt the ciphertext or not according to verification results.

Description

technical field [0001] The invention belongs to the technical field of computers, and relates to a proxy re-encryption method capable of entrusting verification to achieve CCA security, which can be applied to cloud computing, distributed file systems, mail systems and the like. Background technique [0002] Cloud computing is an emerging computing model. It provides convenient, on-demand network access. This advantage enables users with poor computing resources to obtain powerful computing and storage capabilities through the cloud platform. Therefore, cloud computing technology has developed rapidly in recent years, and the user base is also increasing day by day. In this process, in order to protect the privacy of user data, it is necessary to encrypt user data before performing other operations to avoid damage to user rights. Proxy re-encryption technology, as a special type of public key encryption technology, allows a proxy to re-encrypt ciphertext without revealing...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to address the deficiencies of the above-mentioned prior art, and propose a proxy re-encryption method with CCA security that can be delegated for verification. The signature algorithm is used to ensure that even illegal users can obtain public key encryption and private encryption from the stage of entrusting third-party verification. key, illegal users cannot forge legal public key encrypted ciphertexts, so as to achieve CCA security, which is used to solve the problem of insufficient security of encryption methods existing in the prior art

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