Research Of Attribute Based Cryptographic Technology And Its Application In Two-dimensional Code

The asymmetric cryptography view a unique identity of user as public key,however,the attribute based cryptography replaced the identity by an attribute set and bind attribures with an access structure, and by setting the access control structure to achieve data confidentiality,fine-grained access control and the multi communication mode. And how to realize the attributes revocation is the key issues for this encryption technology to meet the actual requirement;secondly,in most of the ciphertext policy attribute based encryption scheme,the length of ciphertext will increases linearly with the increases of access policy complexit.Two-dimensional code is easy to use but is simple,making the vulnerability;How to realize the two-dimensional code revocation controls and how to write confidential information in the two-dimensional code limited storage space is important.In this paper,I put forward new attribute based encryption scheme and put forward the corresponding solutions to solve the security problem of the two-dimensional code:(1) Research on ciphertext-policy attribute-based sincryption scheme with revocation:in the light of the problem that the attribute revocation can not be implemented in the existing scheme.Combined with the key division,proxy re encryption method and the intermediate agent structure.Contribute the revocation list based on the attribute revocation protocol,and analysis the security of the scheme.(2) Research on attribute revocable attribute-based encryption with constant ciphertext length : in the study of existing ciphertext length constant attribute encryption scheme, on the introduction of multiple attribute values and strategies, a ciphertext length constant revocable attribute encryption scheme, based on cryptographic properties of ciphertext length constant attribute revocable encryption scheme is proposed in this paper, and provable security theory to the solution of the security is proved.(3) The design and realize of a two-dimensional code system based on our newly attribute-based sincryption scheme.For the mobile terminal of the two-dimensional code attribute signed secret system design and Implementation: introducing these attributes can be revoked signcryption scheme, using the oriented object method and UML(Unified Modeling Language) to design a for mobile terminal security of twodimensional code sharing system; finally attribute can be revoked signcryption scheme is implemented based on pairing based cryptography library. At the same time, the results are applied to the simulation of the Android platform realization.