Research On Content Extraction Signature Scheme

With the rapid development of computer network technology, the increasing importance of information security. Digital signatures can provide authentication, data integrity, authentication and non-repudiation services for data transmission. Therefore, it is a research hotspot in recent years. At present, researchers have proposed many types of digital signature and proposed, Identity-based digital signature, Attribute-based digital signature and so on. The research of content extraction signature is very important, therefore, this article in view of the current signature scheme is deficient, and does the following:In the application of multi-participation, content extraction signature scheme can solve the information multiple signatures and multiple authentication problems in the multiple transmission.Therefore, according to the ideas of the short signature, we propose a content extraction signature scheme based on short signature. In the scheme, it shortens the length of each sub-messages signature. Even if in the worst cases, the length of a signature is n×170 bits, and compare with content extraction signatures based on RSA signature, the proposed scheme is the shortest. We show that the proposed signature scheme can defend existential forgery on adaptively chosen message attack in the random oracle model, and by the practical application show the practicability of this scheme.The idea of forward security digital signature is to reduce the loss of the key leakage to the lowest degree. For achieving the really forward security, it not only need the secret key of signature forward security, but also guarantee the signature forward security. Hence, according to the ideas of the forward security digital signature, we propose a content extraction signature scheme based on short signature and based on RSA, the scheme of secret key is refreshed automatically with different period time while the public key is fixed in the whole lifetime. In different period time, the different period signature secret key is adopted; the validity of signature is verified by using the system public key. In this scheme, even if the secret key of current time period is compromised, the attacker can not forge the secret key and the signature of the past period time. Finally, by analyzing the computational efficiency, we obtain with a forward secure based on RSA signature schemes have high efficiency.Existing access control schemes for cloud storage can only send different messages according to user’s attributes, which leads to utilization rate is not high. In order to overcome this shortcoming,firstly, we design a content extraction signature scheme based on ElGamal. Then, we propose a new access control scheme for cloud storage based on content extraction signature and attributeencryption cryptosystems. The proposed scheme combines access control with encryption and realizes fine-grained access control at the same time. The scheme can send sub-messages to the corresponding users depending on user’s attributes, improves the utilization of the message and has better applicability.