Foundations of Secure Storage for Encrypted Instant Messaging

加密即时消息安全存储的基础

• 批准号: 461612530
• 负责人: Professor Dr.-Ing. Tibor Jager
• 金额: --
• 依托单位: Lehrstuhl für IT Security and Cryptography
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/461612530?language=en
• 关键词: Foundations; Secure; Storage; Encrypted; Instant

The gold standard to construct and analyze security protocols in modern cryptology is to first define a security model that specifies the use of the protocol and the capabilities of an attacker in a mathematically-precise way, and then show the security of proposed protocols by reduction to well-defined computational hardness assumptions (aka. the "provable security" approach).In the context of secure storage of messages and media in instant messaging environments we are still lacking this level of clarity and rigor of security claims, despite the huge practical importance of this topic. The vast majority of prior research on encrypted instant messaging has focused on messages in transit, but existing results say nothing about the privacy of messages that are stored on a user's device(s). This research project will address this research gap by providing first foundational models and provably-secure constructions for secure storage of messages and media in instant messaging environments. We will define security models that capture desirable advanced security properties, such as forward security, post-compromise security, and more, in a modular fashion. This will enable us to formally analyze and understand the security properties and limitations of existing protocols, in order to develop efficient and practical alternative solutions for the wide variety of use cases that exist in the instant messaging space. A major aspect of the proposal is to construct and analyse provably-secure key derivation schemes for secure backup storage, using advanced cryptographic techniques for oblivious computation.

现代密码学中构建和分析安全协议的黄金标准是首先定义一个安全模型，以数学精确的方式指定协议的使用和攻击者的能力，然后通过简化来显示拟议协议的安全性定义良好的计算难度假设（又名。在即时消息环境中的消息和媒体的安全存储的上下文中，我们仍然缺乏安全声明的这种级别的清晰度和严格性，尽管该主题具有巨大的实际重要性。绝大多数关于加密即时消息的先前研究都集中在传输中的消息上，但现有的研究结果没有提到存储在用户设备上的消息的隐私性。该研究项目将通过提供第一个基础模型和可证明安全的结构来解决即时消息环境中消息和媒体的安全存储问题。我们将定义安全模型，以模块化的方式捕获所需的高级安全属性，如前向安全性，后危害安全性等。这将使我们能够正式分析和理解现有协议的安全属性和局限性，以便为即时消息空间中存在的各种用例开发高效实用的替代解决方案。该提案的一个主要方面是构建和分析可证明安全的密钥导出方案，安全备份存储，使用先进的密码技术不经意计算。