Key isolation signing method based on attribute

Abstract

The invention discloses a key isolation signing method based on attribute, which aims at problems of lack of protective measures for key leakage and increase of computation overhead of a terminal caused by bilinear pairing operation in the prior art. A whole signing system is divided into several independent time slices, when the system enters into a new time slice, a key helper generates a private key updating slice, and a user updates a private key. For a certain file, the user signs with the private key corresponding to the current time slice, and verification result of a signature is also corresponding to a certain time slice of the system. If the private key of the user is leaked within a certain time slice, the system also can keep forward security and backward security in other time slices, and thus, harm of private key leakage is minimized. In a process of signing, any operation of bilinear pairing is not required, and computation overhead of a user terminal is reduced. When system time slices evolve, system public parameters are not required to be updated again, and communication overhead caused by synchronization of the public parameters is reduced.

Description

technical field

[0001] The invention relates to a secret or safe communication technology for digital information transmission, in particular to an attribute-based key isolation signature method. Background technique

[0002] Attribute-based cryptography is an important part of information security. At the same time, attribute-based signature schemes have been widely used in recent years. In the attribute-based signature system, the user's private key corresponds to an attribute structure, and the signature generated by a legitimate user with the corresponding private key can be verified into the corresponding attribute structure owned by him. However, there are still two problems to be solved in the current attribute signature mechanism: first, when a user's attribute private key is leaked, any user who obtains the private key can use the private key to generate a legal signature, thereby bringing There are a series of security risks. Second, most of the current attribute...

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