Using secret sharing for searching in encrypted data

When outsourcing data to an untrusted database server, the data should be encrypted. When using thin clients or low-bandwidth networks it is best to perform most of the work at the server. We present a method, inspired by secure multi-party computation, to search efficiently in encrypted data. XML elements are translated to polynomials. A polynomial is split into two parts: a random polynomial for the client and the difference between the original polynomial and the client polynomial for the server. Since the client polynomials are generated by a random sequence generator only the seed has to be stored on the client. In a combined effort of both the server and the client a query can be evaluated without traversing the whole tree and without the server learning anything about the data or the query

SoK: Cryptographically Protected Database Search

Protected database search systems cryptographically isolate the roles of reading from, writing to, and administering the database. This separation limits unnecessary administrator access and protects data in the case of system breaches. Since protected search was introduced in 2000, the area has grown rapidly; systems are offered by academia, start-ups, and established companies. However, there is no best protected search system or set of techniques. Design of such systems is a balancing act between security, functionality, performance, and usability. This challenge is made more difficult by ongoing database specialization, as some users will want the functionality of SQL, NoSQL, or NewSQL databases. This database evolution will continue, and the protected search community should be able to quickly provide functionality consistent with newly invented databases. At the same time, the community must accurately and clearly characterize the tradeoffs between different approaches. To address these challenges, we provide the following contributions: 1) An identification of the important primitive operations across database paradigms. We find there are a small number of base operations that can be used and combined to support a large number of database paradigms. 2) An evaluation of the current state of protected search systems in implementing these base operations. This evaluation describes the main approaches and tradeoffs for each base operation. Furthermore, it puts protected search in the context of unprotected search, identifying key gaps in functionality. 3) An analysis of attacks against protected search for different base queries. 4) A roadmap and tools for transforming a protected search system into a protected database, including an open-source performance evaluation platform and initial user opinions of protected search.Comment: 20 pages, to appear to IEEE Security and Privac

Extended Functionality in Verifiable Searchable Encryption

Abstract. When outsourcing the storage of sensitive data to an (un-trusted) remote server, a data owner may choose to encrypt the data beforehand to preserve confidentiality. However, it is then difficult to efficiently retrieve specific portions of the data as the server is unable to identify the relevant information. Searchable encryption has been well studied as a solution to this problem, allowing data owners and other au-thorised users to generate search queries which the server may execute over the encrypted data to identify relevant data portions. However, many current schemes lack two important properties: verifia-bility of search results, and expressive queries. We introduce Extended Verifiable Searchable Encryption (eVSE) that permits a user to verify that search results are correct and complete. We also permit verifiabl

Distributed enterprise search using software agents

In this paper we introduce a distributed information retrieval system using agent-based technology. In this multiagent system, each agent has its own specific task and can be used to handle a specific document repository. The system is designed to automatically comply with access restriction rules that are normally enforced in companies. It is used in the administration offices of the German capital city Berlin where it serves as a testbed for further research on aggregated search in an enterprise environment with roughly 50,000 employees

Enhanced Searchable Public Key Cipher Text With Hidden Structures For Fast Keyword Search

Existing semantically secure public-key searchable coding schemes take search time linear with the overall variety of the cipher texts. This makes retrieval from large-scale databases preventative. To alleviate this drawback, this paper proposes Searchable Public-Key Cipher texts with Hidden Structures (SPCHS) for keyword search as quick as potential while not sacrificing linguistics security of the encrypted keywords. In SPCHS, all keyword-searchable Cipher texts area unit structured by hidden relations, and with the search trapdoor such as a keyword, the minimum info of the relations is disclosed to an enquiry rule because the steering to search out all matching Cipher texts expeditiously. We have a tendency to construct a SPCHS theme from scratch during which the Cipher texts have a hidden star-like structure. We have a tendency to prove our theme to be semantically secure within the Random Oracle (RO) model. The search quality of our theme relies on the particular variety of the Cipher texts containing the queried keyword, instead of the amount of all Cipher texts. Finally, we have a tendency to gift a generic SPCHS construction from anonymous identity-based coding and collision-free full-identity malleable Identity-Based Key Encapsulation Mechanism (IBKEM) with namelessness. We have a tendency to illustrate 2 collision-free full-identity malleable IBKEM instances, that area unit semantically secure and anonymous, severally, within the artificial language and customary models

Distributed Searchable Symmetric Encryption

Searchable Symmetric Encryption (SSE) allows a client to store encrypted data on a storage provider in such a way, that the client is able to search and retrieve the data selectively without the storage provider learning the contents of the data or the words being searched for. Practical SSE schemes usually leak (sensitive) information during or after a query (e.g., the search pattern). Secure schemes on the other hand are not practical, namely they are neither efficient in the computational search complexity, nor scalable with large data sets. To achieve efficiency and security at the same time, we introduce the concept of distributed SSE (DSSE), which uses a query proxy in addition to the storage provider.\ud We give a construction that combines an inverted index approach (for efficiency) with scrambling functions used in private information retrieval (PIR) (for security). The proposed scheme, which is entirely based on XOR operations and pseudo-random functions, is efficient and does not leak the search pattern. For instance, a secure search in an index over one million documents and 500 keywords is executed in less than 1 second

Developing a Framework to Implement Public Key Infrastructure Enabled Security in XML Documents

This paper concentrates on proposing a framework to implement the PKI enables security in XML documents, by defining a common framework and processing rules that can be shared across applications using common tools, avoiding the need for extensive customization of applications to add security. The Framework reuses the concepts, algorithms and core technologies of legacy security systems while introducing changes necessary to support extensible integration with XML. This allows interoperability with a wide range of existing infrastructures and across deployments. Currently no strict security models and mechanisms are available that can provide specification and enforcement of security policies for XML documents. Such models are crucial in order to facilitate a secure dissemination of XML documents, containing information of different sensitivity levels, among (possibly large) user communities

Towards a secure and efficient search over encrypted cloud data

Includes bibliographical references.2016 Summer.Cloud computing enables new types of services where the computational and network resources are available online through the Internet. One of the most popular services of cloud computing is data outsourcing. For reasons of cost and convenience, public as well as private organizations can now outsource their large amounts of data to the cloud and enjoy the benefits of remote storage and management. At the same time, confidentiality of remotely stored data on untrusted cloud server is a big concern. In order to reduce these concerns, sensitive data, such as, personal health records, emails, income tax and financial reports, are usually outsourced in encrypted form using well-known cryptographic techniques. Although encrypted data storage protects remote data from unauthorized access, it complicates some basic, yet essential data utilization services such as plaintext keyword search. A simple solution of downloading the data, decrypting and searching locally is clearly inefficient since storing data in the cloud is meaningless unless it can be easily searched and utilized. Thus, cloud services should enable efficient search on encrypted data to provide the benefits of a first-class cloud computing environment. This dissertation is concerned with developing novel searchable encryption techniques that allow the cloud server to perform multi-keyword ranked search as well as substring search incorporating position information. We present results that we have accomplished in this area, including a comprehensive evaluation of existing solutions and searchable encryption schemes for ranked search and substring position search