云环境下对称可搜索加密研究综述

黄一才; 李森森; 郁滨

doi:10.11999/JEIT211572

云环境下对称可搜索加密研究综述

doi: 10.11999/JEIT211572

信息工程大学郑州 450001

基金项目: 国家自然科学基金(61772547)

详细信息

作者简介:
黄一才：男，讲师，博士生，主要研究方向为安全云存储系统、移动存储、短距离无线通信安全等

李森森：男，讲师，硕士，研究方向为物联网安全、安全云存储系统等

郁滨：男，教授，博士生导师，主要研究方向为信息安全、无线网络安全、视觉密码等

通讯作者:
黄一才　huangyicai3698@163.com

中图分类号: TN918.4; TP399
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- 被引次数: 0
出版历程
- 收稿日期: 2021-12-27
- 修回日期: 2022-07-07
- 录用日期: 2022-07-14
- 网络出版日期: 2022-07-19
- 刊出日期: 2023-03-10

A Survey of Symmetric Searchable Encryption in Cloud Environment

Information Engineering University, Zhengzhou 450001, China

Funds: The National Natural Science Foundation of China (61772547)

摘要

摘要: 云存储技术是解决大容量数据存储、交互、管理的有效途径，加密存储是保护远程服务器中用户数据隐私安全的重要手段，而可搜索加密技术能在保证用户数据安全前提下提高系统可用性。对称可搜索加密以其高效的搜索效率得到人们的广泛关注。总体而言，相关研究可归纳为系统模型、效率与安全、功能性3个层次。该文首先介绍了对称可搜索加密(SSE)系统典型模型，然后深入分析了搜索效率优化、安全性分析的常用手段和方法，最后从场景适应能力、语句表达能力、查询结果优化3个方面对方案功能性研究进行了梳理，重点对当前研究的热点和难点进行了总结。在此基础上，进一步分析了未来可能的研究方向。
- 对称可搜索加密 /
- 安全云存储系统 /
- 云计算 /
- 前向隐私 /
- 后向隐私
Abstract: The technology of cloud storage is an effective way to solve the problems in high-capacity data storage, interaction and management. Using encrypted data in cloud servers is an important means to protect the privacy and security of user data in remote servers. Searchable encryption technology can improve the system availability on the premise of ensuring the security of user data. For its search efficiency, the Symmetric Searchable Encryption (SSE) has become a hot research topic. In general, the related research can be summarized into three aspects: the system model, efficiency and security, and usability. Firstly, the typical models of Symmetric Searchable Encryption(SSE) system are introduced. Then, common methods for search efficiency optimisation and security analysis are analysed in depth in this paper. Finally, from the aspects of scene adaptability, sentence expression ability and query result optimization, the research on scheme usability is combed and the hot spots and difficulties of the current research are summarized. On this basis, the possible research hotspots in the future are further analyzed.
- Symmetric Searchable Encryption(SSE) /
- Security cloud storage system /
- Cloud compute /
- Forward private /
- Backward private

HTML全文

图 1 可搜索加密云存储系统“单写多读”应用场景示意

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图 2 当前研究热点和关键问题

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图 3 各安全定义之间的相互关系

下载: 全尺寸图片幻灯片

表 1 典型SSE方案对比

方案	特点	通信开销	计算开销	前向隐私	后向隐私
Song等人^[9]	SWP	$O\left( {{n_w}} \right)$	$O\left( {{\text{DB}}} \right)$	×	×
Goh^[11]	Bloom Filter	$O\left( {{n_w}} \right)$	$O\left( D \right)$	×	×
Sophos^[33]	单向陷门置换	${ { {O} } }\left( { {n_w} } \right)$	$O\left( {{a_w} + {d_w}} \right)$	√	×
Diana_del^[30]	约束PRFs	$O\left( {{n_w} + {d_w}{{\log }_2}{a_w}} \right)$	$O\left( {{a_w}} \right)$	√	Type III
Janus++^[32]	SPE	$O\left( {{n_w}} \right)$	$O\left( {{n_w}{d_w}} \right)$	√	Type III
Aura^[31]	SRE	$O\left( {{n_w}} \right)$	$O\left( {{n_w}} \right)$	√	Type II

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表 2 领域内研究方向的代表性研究成果及热点问题

方向		代表性研究成果	难点问题	未来值得关注的研究热点
系统模型	模型描述	方案形式化描述^{[3, 8]}	更通用模型及模型的分析	通用模型不同场景下相互转化的方法和条件。
系统模型	应用场景	医疗、政务、通用存储等^[4-7]	安全性、效率、功能性平衡	国内较成熟、影响力较大的应用较少
搜索效率优化	索引结构	正排索引^[11]，倒排索引^[8]，双向索引^[13]、树形索引^[14]，非索引结构搜索^{[9, 10]}	索引准确性和适应未来应用的能力，索引安全对文件内容安全的影响	非索引结构中搜索效率优化及应用研究
搜索效率优化	搜索方式	Bloom过滤器^{[15, 16]}，并行搜索^[17]，分类存储^[19-22]	结果精确的SSE方案及云环境下性能测试与分析	结合磁盘数据存取特点或特殊硬件的索引结构优化；云环境下分布式数据存储效率优化
安全性研究	安全性分析	安全性定义^{[3, 8, 30]}，前向/后向隐私^{[2, 30, 31]}，其他典型方案^{[14, 23, 26, 28]}	动态方案安全性分析、通信开销与安全性平衡问题	动态SSE方案安全性定义和分析方法；采用新技术设计安全性更高SSE方案
安全性研究	攻击方式	选择关键词攻击^{[8, 11, 34]}，文件注入攻击^{[35, 36]}，推理攻击^{[24, 37]}	推理攻击的预防问题	恶意服务器假设下方案抵抗攻击的能力研究
功能性扩展	场景适应能力	S/S^{[1, 11, 13, 33]}，S/M^{[40-42, 44, 45, 47]}	多用户场景下安全性研究	采用新技术实现的S/S方案；“多读”场景中不可信服务器假设下的安全性研究
	语句表达能力	单关键词^{[9, 11, 30-33]}，连接关键词^{[40, 48, 50, 52]}，模糊关键词^{[53, 55, 56]}，语义关键词^{[57, 59, 61]}	非集合扩展的模糊关键词搜索，现有语义模型应用于SSE方案的安全性分析	更灵活地模糊关键词搜索方案或语义关键词搜索方案研究
	结果优化	结果排序^[65]，结果可验证^[69-72]	空结果校验，动态方案验证，排序准确性等	实现大多依赖公钥算法，优化后对原SSE方案性能的影响值得关注

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