TWC: Small: New Advances for Efficiently-Searchable Encryption

目前全球范围内的趋势是远程数据存储解决方案，如云存储，其中必须有效地访问不安全网络上的大型数据存储，以及日益增加的安全要求，强调需要支持大型加密数据库上的高效搜索功能。可搜索加密是效率、功能和安全性的平衡行为。这些解决方案要么需要大量的交互和计算，对每个查询进行线性数据扫描，这对于大型数据库来说是不允许的，要么需要提前知道所有数据。本研究通过关注三个关键领域来推进高效可搜索加密（ESE）的最新发展：保序加密的新安全保证，模糊查询的可搜索加密，以及寻求ESE的一般定义。PI进行了保序加密的密码学研究，以支持对远程加密数据的有效范围查询。该项目澄清了以前定义的安全保证，并研究了替代设置，以开发新的安全解决方案。本研究的重点是模糊查询，返回数据库元素对应的消息是接近底层查询消息。这项工作启动了模糊可搜索加密（FSE）的第一个正式的密码学研究。特别是，工作的重点是制定适当的安全定义和建立可证明安全的FSE计划。本研究旨在寻求一个一般性的定义，将涵盖所有已知类型的ESE，并调查相关的不可能性问题。该研究将各种ESE的安全定义扩展到数据库的整体安全。

Current worldwide trends towards remote data storage solutions such as cloud storage, in which large stores of data on insecure networks must be efficiently accessible, and increasing security requirements emphasized the need to support efficient search functionality on large encrypted databases. Searchable encryption is a balancing act of efficiency, functionality, and security. The solutions either require extensive interaction and computation, linear data scan on each query, which is prohibitive for large databases, or knowing all data in advance. This research advances the state of the art of efficiently-searchable encryption (ESE) by focusing on three key areas: new security guarantees for order-preserving encryption, searchable encryption for fuzzy queries, and seeking a general definition of ESE. The PI has conducted a cryptographic study of order-preserving encryption for supporting efficient range queries on remote encrypted data. This project clarifies the security guarantees of the previous definition and studies the alternative settings in order to develop new secure solutions. This research focuses on fuzzy queries which return database elements that correspond to messages which are close to the underlying queried message. This work initiates the first formal cryptographic study of fuzzy searchable encryption (FSE). In particular, the work focuses on developing appropriate security definitions and building provably-secure FSE schemes. This research seeks a general definition that will cover all known types of ESE, and investigates related impossibility issues. The research extends security definitions for various ESE to security of the database as a whole.