标题: 基植于双线性配对密码的安全云端储存
Secure Pairing-Based Cloud Storages
作者: 陈荣杰
CHEN RONG-JAYE
国立交通大学资讯工程学系(所)
公开日期: 2012
摘要: 交通大学资讯工程学系

计画名称:基植于双线性配对密码的安全云端储存

研究者:陈荣杰

经费来源:行政院国家科学委员会

关键词:双线性配对密码学;椭圆曲线密码学;可搜寻式公开金钥加密系统;属性加密;

资料拥有证明;云端储存

云端运算(cloud computing)的发展,让使用电脑系统的行为模式有了重大的改变。 以往,电脑系统使用人需要拥有自己的软硬体设备,有了云端运算,资料储存、处理 与传输等资源都由云端提供,需要时才向云端要求使用,不仅能使用比以往更快更多 的资源,也不需维护自己的软硬体设备,因此个人、公司与政府都能将他们的资料改 储存在云端,并使用云端的资料处理、传输等功能。虽然云端运算在电脑资源的使用 上提供了更好的选择,但相应而生的便是安全性与隐私的风险,使得云端运算不易普 及,政府与企业在使用时也多了一层考量,即便目前很多加密机制,很轻易就能达到 资料保护的目的,但并不适合用于云端运算上,因此,为了达到云端运算的安全与效 率,必须设计新的系统。

本实验室十余年致力于密码学的研究,尤其是椭圆曲线密码学与双线性配对密码 学,这些都是数学代数中较为艰深的部份,我们不仅有厚实的数学理论基础,也有扎 实的程式能力,能将这些密码系统实现,在实作上,我们能以理论的特性来调整系统 参数,而非尝试性的实验结果,在研究过程中发现,唯有双线性配对密码系统,才能 完整地满足云端储存的安全需求,其中包含双线性配对签章(pairing-based signature)、 属性加密(attribute-based encryption)、可搜寻式公开金钥加密系统(public-key encryption with keyword search)以及资料拥有证明(proof-of-data possession)四类的密码原型。

云端安全联盟(Cloud Security Alliance, CSA)对于云端储存资料的安全提出了标 准,先定义资料的生命周期,分别为建立(create)、储存(store)、使用(use)、分享(share)、 归标(archive)、销毁(destroy),再针对每一生命周期,提出相对应之安全要求。在建立 时,对资料需有分类(classify)、存取权限(access right)的功能;在储存时,能达到存取 控管(access control)、资料加密(encryption)、权限管理(rights management)与资料发现 (content discovery);在使用阶段,需监控使用过程(activity monitoring and enforcement)、 权限管理、逻辑控管(logical control)、应用程式安全(application security);在分享时, 需达到内容管理(content management)、加密、逻辑控管与应用程式安全;归标时,要 有加密与财产管理(asset management);在销毁阶段,密码粉碎(crypto-shredding)、安全 删除(secure deletion)与资料发现都是重要的,其中资料发现是为了确保资料已删除。

透过上述标准,对于云端储存(cloud storage),本计昼提出四个需求:(1)机密性 (confidentiality):只有合法的使用者才能解读储存于云端的资料;(2)完整性(integrity): 使用者能察觉云端储存是否非法更动储存的资料;(3)查询结果完整性(query-result integrity):云端储存能提供搜寻功能,其回传搜寻结果可验证并保证完整;(4)可稽核 (auditability) •任何资料的更动都有资料拥有者的授权,并有纪录。本计昼将研究上述 四类密码系统,并将其整合,提出安全云端储存系统,并符合云端安全联盟的标准。
Department of Computer Science, NCTU

Title : Secure pairing-based cloud storages Principal Investigator : Rong-Jaye Chen Sponsor : National Science Council

Keywords : pairing-based cryptography, elliptic curve cryptography, public-key encryption with keyword search, attribute-based encryption, proof-of-data possession, cloud storage

Cloud computing enables a new paradigm of information and communication resource on demand. Users, enterprises, governments start to consider moving their data into the cloud to enjoy its storage capacity and computation capability. While cloud computing brings in promising opportunities, it also brings along security and privacy risks, which hurdle the public to adopt the cloud technologies. There are a number of encryption techniques which are the easiest way to protect cloud data and services. However, as these encryptions add to the complexities, new schemes must be devised to manage encrypted data securely and efficiently.

Our research team has been dedicated to cryptography for years especially in elliptic curve and paring-based cryptography. We have not only solid mathematical background of the underlying mathematical structures but also strong implementation ability to realize these cryptosystems. We can also adjust the system parameters based on the theoretical characteristics instead of (heuristic) experimental optimization. During our research, we find a set of pairing-based cryptographic primitives which can uniquely meet the requirements of the cloud storage. They are pairing-based signature (PBS) scheme, attribute-based encryption (ABE) scheme, public-key encryption with keyword search (PEKS) and proof-of-data-possession (PDP) scheme.

According to the guideline for cloud data security proposed by Cloud Security Alliance (CSA), the data security lifecycle includes create, store, use, share, archive, and destroy. In create stage, it requires classify and access rights. In store stage, access control, encryption, right management, and content discovery are important. In use stage, activity monitoring and enforcement, rights management, logical control, and application security are concerned. In share stage, content management, encryption, logical control, and application security are considered. In archive stage, encryption and asset management should be implemented. In destroy stage, the functionality of crypto-shredding, secure deletion, and content discovery are provided for security concern.

Our goal is to design one management suite for the data in encrypted form stored in the cloud fulfilling the following four requirements: (1) Confidentiality: the cloud storage should not learn any information of the stored data. (2) Integrity: the cloud storage should be caught if any unauthorized tampering of stored data happens. (3) Query-Result Integrity: the cloud storage could search over (encrypted) stored data once authorized by the data owner and the returned results are authenticated and complete. (4) Audibility: any manipulation on stored data should be granted by data owner and recorded for further forensic and judicial investigations. We make use of four pairing-based cryptographic primitives along with our novel design to construct the secure and practical cloud storage management suite, which is aligned with the suggestion from the Cloud Security Alliance (CSA).
官方说明文件#: NSC101-2221-E009-138
URI: http://hdl.handle.net/11536/98351
https://www.grb.gov.tw/search/planDetail?id=2629473&docId=394652
显示于类别:Research Plans