公开(公告)号：US11463237B2

公开(公告)日：2022-10-04

申请号：US17172145

申请日：2021-02-10

Applicant: HUAZHONG UNIVERSITY OF SCIENCE AND TECHNOLOGY

Inventor： Peng Xu ,  Tianyang Chen ,  Yubo Zheng ,  Hai Jin ,  Wei Wang

IPC: H04L29/06 ,  H04L9/06 ,  G06F16/2455 ,  H04L9/08

Abstract: The present invention relates to a method and a system for robust, searchable, symmetrical encryption, the method comprising: during initialization, having a retrieval server perform retrieval on stored ciphertext information according to a searchable ciphertext and retrieval trapdoor information (Cntupd, K, Locgrp) sent by a client, wherein, the retrieval server acquires a last received first ciphertext set Cnew from a ciphertext database CDB just before the present retrieval according to a retrieval key K and an encryption counter Cntupd sent by the client, acquiring a second ciphertext set Ccache in a retrieval request history from a cache ciphertext database GRP according to a cache ciphertext index Locgrp, and merging the first ciphertext set Cnew and the second ciphertext set Ccache to form a retrieval set , and sending it to the client for decryption. The present invention is able to improve retrieval performance of searchable symmetrical encryption algorithm with robust forward and backward secrecy and to make searchable symmetrical encryption algorithm more practical.

公开(公告)号：US11784815B2

公开(公告)日：2023-10-10

申请号：US17444613

申请日：2021-08-06

Applicant: Huazhong University of Science and Technology

Inventor： Peng Xu ,  Yubo Zheng ,  Tianyang Chen ,  Hai Jin ,  Wei Wang

IPC: H04L29/06 ,  H04L9/30 ,  G06F16/903 ,  H04L9/06

CPC classification number: H04L9/3073 ,  G06F16/90335 ,  H04L9/0618 ,  H04L9/0643

Abstract: A method for increasing the difficulty for attackers to launch keyword guessing attacks, which uses a time-delay encryption with a keyword search based on a public key that generates searchable ciphertexts and/or files ciphertexts for keywords of at least one file that uploaded by time-delay encryption from a cloud server. A system for implementing the method is also described.

公开(公告)号：US11770250B2

公开(公告)日：2023-09-26

申请号：US17444224

申请日：2021-08-02

Applicant: Huazhong University of Science and Technology

Inventor： Peng Xu ,  Tianyang Chen ,  Yubo Zheng ,  Hai Jin ,  Wei Wang

IPC: H04L9/06 ,  H04L9/40 ,  H04L9/08 ,  H04L67/10 ,  H04L67/1097 ,  H04L9/00 ,  H04L9/30

CPC classification number: H04L9/30 ,  H04L9/0618 ,  H04L9/50

Abstract: The present invention relates a method for ensuring search completeness of searchable public key encryption, applicable to a blockchain network formed by a plurality of computer nodes. The method at least comprises: the blockchain network receiving a keyword ciphertext and a corresponding file-identifier ciphertext generated by a transmitting end based on the public key encryption, and at least one miner storing the ciphertexts in a ciphertext table; the blockchain network receiving a search trapdoor Tw transmitted by a receiving end, generated according to a private key and a keyword w to be searched; the at least one miner in the blockchain network performing a secure search based on information of a state table and the search trapdoor Tw, and outputting a search result to the blockchain network; and the blockchain network feeding the search result back to the receiving end. The invention uses the blockchain technology to solve the long-standing search completeness problem in searchable public key encryption, and the proposed method has universality.