Access Control for Information-Theoretically Secure Key-Document Stores

TL;DR

This paper introduces a secure key-based access control method for key-value stores using Shamir's secret-sharing, enabling keyword search, data confidentiality, and malicious client/server detection with efficient performance.

Contribution

It proposes a novel access control technique combining information-theoretic security with keyword search in outsourced key-value stores, preventing data leakage and malicious activities.

Findings

Supports keyword-based retrieval without data leakage

Detects and aborts malicious client access

Efficient performance with 231.5ms for 5,000 keywords and 500,000 files

Abstract

This paper presents a novel key-based access control technique for secure outsourcing key-value stores where values correspond to documents that are indexed and accessed using keys. The proposed approach adopts Shamir's secret-sharing that offers unconditional or information-theoretic security. It supports keyword-based document retrieval while preventing leakage of the data, access rights of users, or the size (\textit{i}.\textit{e}., volume of the output that satisfies a query). The proposed approach allows servers to detect (and abort) malicious clients from gaining unauthorized access to data, and prevents malicious servers from altering data undetected while ensuring efficient access -- it takes 231.5ms over 5,000 keywords across 500,000 files.