Privacy Preserving and Serverless Homomorphic-Based Searchable Encryption as a Service (SEaaS)

Abstract

Serverless computing has seen rapid growth, thanks to its adaptability, elasticity, and deployment agility, embraced by both cloud providers and users. However, this surge in serverless adoption has prompted a reevaluation of security concerns and thus, searchable encryption has emerged as a crucial technology. This paper explores the Searchable Encryption as a Service (SEaaS) and introduces an innovative privacy-preserving Multiple Keyword Searchable Encryption (MKSE) scheme within a serverless cloud environment, addressing previously unmet security goals. The proposed scheme employs probabilistic encryption and leverages fully homomorphic encryption to enable operations on ciphertext, facilitating searches on encrypted data. Its core innovation lies in the use of probabilistic encryption for private multi-keyword searches. To validate its practicality, we deploy the scheme on the public cloud infrastructure, “Contabo,” and conduct rigorous testing on a real-world dataset. The results demonstrate that our novel scheme successfully preserves the privacy of search queries and access patterns, achieving robust security. This research contributes to the field of serverless cloud security, particularly in the context of searchable encryption, by providing a refined solution for safeguarding data while maintaining usability in a serverless computing landscape.

Keywords

• Homomorphic encryption
• cloud computing
• multi-keyword search
• serverless computing
• trapdoor generation
• search pattern security