The Research Of Secret Sharing With General Access Structures Based On RSA

Secret sharing is an important research direction in the field of information security and cryptography, which can effectively ensure the security of information in the process of storage, transport and using. Secret sharing prevents excessive concentration of power being abused and improves the security, robustness and fairness of the system.In this dissertation, the research background and current situation of secret sharing are introduced. The threshold secret sharing, verifiable secret sharing and multi-secret sharing are analyzed. The secret sharing based on the general access structure is studied. The research production as well as typical schemes based on the general access structure of secret sharing is emphatically analyzed. Based on the RSA cryptosystem, a new multi-secret sharing scheme with general access structures is proposed. After that, the analysis of the security of the scheme is presented. The scheme has the following characteristics:(1) The dealer designates the authorized subsets, and all of the participants in an authorized subset can recover the secret by mutual cooperation. Each participant selects a secret share by himself. These can avoid a dishonest behavior of the distributor. The secret recuperator use the secret share shadows to recover the secret and do not expose the secret shares, so the secret shares are reusable.(2) When the shared secret is renewed, the dealer changes the secret shadow rather than the secret shares, so the secret share can be used in many secrets.(3) This scheme can identify the participants’ utual cheating and prevent the malicious fraud of the participants effectively by verification secret share shadow.Finally, a prototype system of a secret sharing scheme with general access structures based on the RSA is designed with VC++6.0. Then, some critical functions of modules are analyzed. The experimental results show that the scheme is correct and available.