Research And Application Of Attribute-Based Encryption With Predicate Encoding

As a kind of public-key cryptography,Attribute-Based Encryption(ABE)combines encryption and the idea of access control together.It not only provides one-to-many encryption but also provides fine-grained access control.With the features above,ABE is widely used in cloud computing,cloud-based Internet of Things and wireless body area networks(WBANs).Unfortunately,most Policy Hiding Attribute-Based Encryption(PH-ABE)schemes are partial policy hiding or weak full policy hiding.These schemes can only achieve selective security or are not based on standard hardness assumptions.What's more,most of the Attribute-Based Proxy Re-Encryption(ABPRE)schemes can only convert an ABE type ciphertext into another ABE type ciphertext.There are few schemes on hybrid attribute-based proxy re-encryption(HABPRE),and these schemes always achieve selective security and based on standard hardness assumptions.To solve the two problems above,this thesis analyzes the application of Dual System Encryption and Predicate Encoding in Attribute Based Encryption,Policy Hiding Attribute Based encryption and Attribute Based Proxy Re-Encryption.The contributions of this thesis are as follows:(1)This thesis proposed a new Full Policy-Hiding Attribute-Based Encryption scheme with inner-product predicate encoding.Different from the proposed schemes,this scheme achieves full policy hiding.Even the user who can decrypt the ciphertext is not able to get any information about the access structure.The privacy of the users is proposed in this way.In terms of security,this scheme achieves adaptive security based on the standard hardness assumption.Otherwise,the scheme is constructed with prime order asymmetric bilinear pairing,which makes this scheme more efficient than other proposed schemes.(2)This thesis proposed a new hybrid Attribute Based Proxy Re-Encryption scheme with monotone span program predicate encoding.This scheme makes it possible to convert an ABE type ciphertext to an IBE type ciphertext by the proxy server with the reencryption key,and the proxy server can not get any information about the plaintext.Meanwhile,this scheme also achieves adaptive security based on the standard hardness assumption.Comparing with proposed schemes,this scheme is constructed with prime order asymmetric bilinear pairing.At the same time,this scheme is constructed with an efficient monotone span program(MSP),so the time required for decryption of this scheme is much shorter than proposed schemes.