Research On Attribute-Based Public Key Cyptosystem And Applications From Lattice

With the development and progress of the scientific,information security has become the most concern issue in all walks of life.With the cloud computing development and mass data storage,these technologies can be widely used in the security of information.Only by ensuring the security of information can new technologies be certainly applied.Cryptography plays an important role in information security,and the development of cryptography ensures the secure transmission,storage and use of information.With the development of public key cryptography,there are various cryptographic systems appeared.The attribute-based Public key cyptosystem is a more efficient cipher system than traditional cryptography.It comes with the Identity-based cryptosystem,this paper constructs encryption,signature and signcryption schemes are all based on attribute-based public key cyptosystem.With the advent of the era of quantum computers coming,the big data storage and cloud computing are very hot.So we need a more secured cryptography.The traditional cryptography system based on the integer factorization problem or discrete log problem is now impacted and challenged.So the cryptography which can against quantum attack has become one of the hottest topic in cryptography.Lattice-based cryptosystems are recognized as the cryptographic system that can resist quantum attacks.This paper on the basis of theory of lattice,the main work is as follows:Apply theory of lattice to attribute-based encryption and use a multi-secret sharing scheme of Pang Liaojun and dynamic multi-attribute based encryption of Guo Zhenzhou's scheme,the scheme of attribute-based multiple encryption was proposed.The flexibility of encryption and decryption is improved,and the computational complexity of the encryption and decryption process is reduced.And the security analysis is reduced to be LWE hard problem.Using the improved bonsai trees model of Wang Fenghe's,a signature scheme was proposed.The scheme reduces the length of matrixs and the length of public key and the length of the signature,it improves signature efficiency by using the attributes and messages' s hamming weight.The scheme lets users add some information of their own.That is,the key generation get no information of the secret key.The security signature of non-trusted third party is realized,and the security of the scheme is analyzed by using SIS hard problem.With the work done in the first two parts,combined with the signature scheme.An attribute-based signcryption scheme for lattice is proposed.This scheme need a trusted third party.Under the random oracle model,the security of the scheme is analyzed.And this scheme is existential unforgeable under the chosen access structure and message attack and distinguishability under the chosen plaintext attack.