Abstract:

Existing access control schemes in cloud storage can only send different messages according to users’ attributes, which leads to low utilization rate. In order to overcome this shortcoming, firstly, we design a content extraction signature scheme based on ElGamal; secondly, we propose a new access control scheme in cloud storage based on content extraction signature and attribute encryption system. The proposed scheme combines access control with attribute encryption and realizes finegrained access control at the same time. The scheme can send submessages to corresponding users depending on users’ attributes; it improves the utilization of the message and has better applicability.

Key words: cloud storage;access control;content extraction signature;attribute encryption;discrete logarithm problem