Abstract: In order to improve the computing efficiency of user important data security and virtual machine disk integrity verification in cloud computing model, a secure dynamic update storage strategy based on electronic stream cipher in cloud computing is proposed. Firstly, the cloud service provider introduces the concept of virtualization to maintain the virtualization server, storage, and so on to realize the real-time security migration of the virtual machine. At the same time, a model based on the secure electronic stream cipher is introduced. The encryption/decryption uses the ChaCha20 method to maintain the appropriate security for the user sensitive data in the cloud data, to realize data virtualization and dynamic updating in virtual machine disk. Secondly, a new dynamic version of the Merkle B+ Hash tree (DMBHT) is proposed. This method does not require random Oracle signature scheme, while uses q-strong Diffie-Hellman (q-SDH) secure short signature, and uses effective bit rate as pseudo delete code (Tornado-z code) on the leaf level of DBHT, which can effectively keep the integrity and authenticity between the virtual machine disk. Finally, simulation results show that the proposed algorithm can achieve fast update and secure modification, and the effectiveness of the proposed algorithm is verified.

Key words: cloud computing, electronic stream cipher, secure storage, q-SDH short signature

摘要： 为提高云计算模型中用户重要数据安全性和虚拟机磁盘完整性验证的计算效率，提出一种云计算中基于电子流密码的安全动态更新存储策略。首先，云服务提供商引入虚拟化的概念来维护虚拟化服务器、存储等，实现虚拟机的即时安全迁移。同时，引入了一种基于安全电子流密码的模型，加密/解密使用ChaCha20方法，用于在云数据中心保持对用户敏感数据的适当安全性，实现虚拟机磁盘中数据的安全虚拟化和动态更新。其次，提出了一种新的Merkle哈希散列B+树的动态版本（DMBHT），该方法不需要随机Oracle签名方案，而采用q-SDH安全短签名，在DBHT的叶级上采用有效的码率作为伪删除码（Tornado-z码），可有效保持虚拟机磁盘之间的完整性和真实性。最后，仿真实验结果表明，所提算法可实现快速的更新和安全的修改，验证了所提算法的有效性。

关键词: 云计算, 电子流密码, 安全存储, q-SDH短签名