Paper 2020/732 Original: eprint.iacr.org/2020/732 ↗

Security of Multi-Adjustable Join Schemes: Separations and Implications

Abstract

Database management systems (DBMS) are one of cloud services with great interests in industry and business. In such services, since there is no trust in the cloud servers, the databases are encrypted prior to outsourcing. One of the most challenging issues in designing these services is supporting SQL join queries on the encrypted database. The multi-adjustable join scheme (M-Adjoin) [Khazaei-Rafiee 2019], an extension of Adjoin [Popa-Zeldovich 2012 and Mironov-Segev-Shahaf 2017], is a symmetric-key primitive that supports the join queries for a list of column labels on an encrypted database. In previous works, the following security notions were introduced for Adjoin and M-Adjoin schemes: 3Partition, M3Partition and M3P k , for every integer k . Additionally, simulation-based and indistinguishability-based security notions have been defined by Mironov et al. for Adjoin scheme. In this paper, we extend their results to M-Adjoin and study the relations between all security notions for M-Adjoin. Some non-trivial relations are proved which resolve some open problems raised by [Mironov-Segev-Shahaf 2017].