A password-enhanced and updatable blind key management method in cloud storage

Abstract

The invention discloses a password-enhanced and updateable blind key management method in cloud storage, which belongs to the technical field of communication. The present invention introduces a group of authentication servers. Before interacting with the key server, the user needs to authenticate with the authentication server through a password. At the same time, the user's authentication times are limited within a cycle, preventing impersonation attacks and password guessing attacks by opponents. The present invention resists the collusion of the honest but curious cloud server and the key server. By introducing a group of authentication servers, the key server and the cloud server cannot recover the user's cipher text message even if they collude. The invention introduces a plurality of key servers, avoiding a single-point invalidation attack of a key server.

Description

technical field [0001] The invention belongs to the technical field of communication, and in particular relates to a password-enhanced and updateable blind key management method in cloud storage. Background technique [0002] In the era of data explosion, it has become a trend to store data externally to cloud servers (that is, cloud storage). Cloud storage not only saves users' local storage space, but also promotes users' multi-terminal access and centralized data management. At present, many cloud storage providers can access any information stored on them by users, including the user's outsourced data, which has caused users to worry about the confidentiality of the outsourced data. One of the most widely used methods is: the user encrypts the data in the external memory to protect the confidentiality of the data. [0003] For storage convenience, a user uses the same key when outsourcing to store different data. However, in this approach, any outsourced encrypted dat...

AI Technical Summary

Problems solved by technology

[0004] However, there are some security problems in the above mechanism: the current scheme does not provide a user identity authentication mechanism, and a malicious adversary can obtain the user's encryption key (decryption key) by posing as the user's identity and interacting with the key server.

What's more difficult is that the security of the current updateable blind key management system only depends on the security and reliability of the key server, and the user-specific key update mechanism of the key server requires the key server and the cloud server. Joint participation brings additional communication and computational overhead