Eurus: Towards an Efficient Searchable Symmetric Encryption With Size Pattern Protection

To achieve efficiently search and update on outsourced encrypted data, dynamic searchable symmetric encryption (DSSE) was proposed by just leaking some well-defined leakages. Though small, many recent works show that an attacker can exploit these leakages to undermine the security of existing DSSE schemes. In particular, even seemingly harmless size pattern perform severe attacks. Many exiting schemes resort oblivious RAM (ORAM) hide search/access pattern; however, such powerful cryptographic primitive cannot protect leakage. this article, we first lead more information leakages, which is not well studied or protected We then extend privacy notion for capture leakage, achieving a strong forward backward definition. Following definition, propose new scheme Eurus. Eurus eliminate relying multi-server ORAM scheme, meanwhile reducing with reasonable efficiency. reduce leakage significantly better efficiency, compared state-of-the-art reduction