Автоматизированное создание правил управления доступом к данным средствами СУБД

Прикладные программы доступа к базам данных в корпоративной информационной системе с целью обеспечения гибкости политики безопасности при доступе к данным требуют управления доступом через программирование механизма доступа на уровне строк и столбцов таблиц БД (Row Level Security). Рост числа пользователей и таблиц в БД увеличивает сложность этого процесса управления. Предлагается метод автоматизированного создания правил управления доступом к данным программными средствами активных СУБД для сокращения числа операций при создании пользовательских пространств. Предложен алгоритм для автоматического создания SQL-запросов Row Level Security механизма, который подходит для большинства СУБД, использующих избирательное управление доступом. Метод использует структурно-должностную иерархию пользователей, словари базы данных и программные шаблоны операций управления доступом в различных СУБД.Database applications in enterprise information system for flexibility of security policy large require the Row Level Security mechanism. Large number of users and tables in database increases the process complexity of administration. In this paper, we propose automated design method of hierarchical access control in database to reduce the number of operations for user data spaces creation. An algorithm for automatic creation of SQL-queries in the Row Level Security, which is suitable for most databases using the Discretionary Access Control, is proposed. Method uses structural-post hierarchy users, database dictionary and templates of access control commands for different DBMS

АВТОМАТИЗИРОВАННОЕ СОЗДАНИЕ ПРАВИЛ УПРАВЛЕНИЯ ДОСТУПОМ К ДАННЫМ СРЕДСТВАМИ СУБД

Прикладные программы доступа к базам данных в корпоративной информационной системе с целью обеспечения гибкости политики безопасности при доступе к данным требуют управления доступом через программирование механизма доступа на уровне строк и столбцов таблиц БД (Row Level Security). Рост числа пользователей и таблиц в БД увеличивает сложность этого процесса управления. Предлагается метод автоматизированного создания правил управления доступом к данным программными средствами активных СУБД для сокращения числа операций при создании пользовательских пространств. Предложен алгоритм для автоматического создания SQL-запросов Row Level Security механизма, который подходит для большинства СУБД, использующих избирательное управление доступом. Метод использует структурно-должностную иерархию пользователей, словари базы данных и программные шаблоны операций управления доступом в различных СУБД.\ud \ud Database applications in enterprise information system for flexibility of security policy large require the Row Level Security mechanism. Large number of users and tables in database increases the process complexity of administration. In this paper, we propose automated design method of hierarchical access control in database to reduce the number of operations for user data spaces creation. An algorithm for automatic creation of SQL-queries in the Row Level Security, which is suitable for most databases using the Discretionary Access Control, is proposed. Method uses structural-post hierarchy users, database dictionary and templates of access control commands for different DBMS.\u

Runtime values driven by access control policies: statically enforced at the level of relational business tiers

Access control is a key challenge in software engineering, especially in relational database applications. Current access control techniques are based on additional security layers designed by security experts. These additional security layers do not take into account the necessary business logic leading to a separation between business tiers and access control mechanisms. Moreover, business tiers are built from commercial tools (ex: Hibernate, JDBC, ODBC, LINQ), which are not tailored to deal with security aspects. To overcome this situation several proposals have been presented. In spite of their relevance, they do not support the enforcement of access control policies at the level of the runtime values that are used to interact with protected data. Runtime values are critical entities because they play a key role in the process of defining which data is accessed. In this paper, we present a general technique for static checking, at the business tier level, the runtime values that are used to interact with databases and in accordance with the established access control policies. The technique is applicable to CRUD (create, read, update and delete) expressions and also to actions (update and insert) that are executed on data retrieved by Select expressions. A proof of concept is also presented. It uses an access control platform previously developed, which lacks the key issue of this paper. The collected results show that the presented approach is an effective solution to enforce access control policies at the level of runtime values that are used to interact with data residing in relational databases.(undefined

A Formal Study of Collaborative Access Control in Distributed Datalog

We formalize and study a declaratively specified collaborative access control mechanism for data dissemination in a distributed environment. Data dissemination is specified using distributed datalog. Access control is also defined by datalog-style rules, at the relation level for extensional relations, and at the tuple level for intensional ones, based on the derivation of tuples. The model also includes a mechanism for "declassifying" data, that allows circumventing overly restrictive access control. We consider the complexity of determining whether a peer is allowed to access a given fact, and address the problem of achieving the goal of disseminating certain information under some access control policy. We also investigate the problem of information leakage, which occurs when a peer is able to infer facts to which the peer is not allowed access by the policy. Finally, we consider access control extended to facts equipped with provenance information, motivated by the many applications where such information is required. We provide semantics for access control with provenance, and establish the complexity of determining whether a peer may access a given fact together with its provenance. This work is motivated by the access control of the Webdamlog system, whose core features it formalizes

Access and privacy control enforcement in RFID middleware systems: Proposal and implementation on the Fosstrak platform

International audienceRadio Frequency IDentification (RFID) technology offers a new way of automating the identification and storing of information in RFID tags. The emerging opportunities for the use of RFID technology in human centric applications like monitoring and indoor guidance systems indicate how important this topic is in term of privacy. Holding privacy issues from the early stages of RFID data collection helps to master the data view before translating it into business events and storing it in databases. An RFID middleware is the entity that sits between tag readers and database applications. It is in charge of collecting, filtering and aggregating the requested events from heterogeneous RFID environments. Thus, the system, at this point, is likely to suffer from parameter manipulation and eavesdropping, raising privacy concerns. In this paper, we propose an access and privacy controller module that adds a security level to the RFID middleware standardized by the EPCglobal consortium. We provide a privacy policy-driven model using some enhanced contextual concepts of the extended Role Based Access Control model, namely the purpose, the accuracy and the consent principles. We also use the provisional context to model security rules whose activation depends on the history of previously performed actions. To show the feasibility of our privacy enforcement model, we first provide a proof-of-concept prototype integrated into the middleware of the Fosstrak platform, then evaluate the performance of the integrated module in terms of execution time

Strong and Provably Secure Database Access Control

Existing SQL access control mechanisms are extremely limited. Attackers can leak information and escalate their privileges using advanced database features such as views, triggers, and integrity constraints. This is not merely a problem of vendors lagging behind the state-of-the-art. The theoretical foundations for database security lack adequate security definitions and a realistic attacker model, both of which are needed to evaluate the security of modern databases. We address these issues and present a provably secure access control mechanism that prevents attacks that defeat popular SQL database systems.Comment: A short version of this paper has been published in the proceedings of the 1st IEEE European Symposium on Security and Privacy (EuroS&P 2016

Secure information sharing on Decentralized Social Networks.

Decentralized Social Networks (DSNs) are web-based platforms built on distributed systems (federations) composed of multiple providers (pods) that run the same social networking service. DSNs have been presented as a valid alternative to Online Social Networks (OSNs), replacing the centralized paradigm of OSNs with a decentralized distribution of the features o↵ered by the social networking platform. Similarly to commercial OSNs, DSNs o↵er to their subscribed users a number of distinctive features, such as the possibility to share resources with other subscribed users or the possibility to establish virtual relationships with other DSN users. On the other hand, each DSN user takes part in the service, choosing to store personal data on his/her own trusted provider inside the federation or to deploy his/her own provider on a private machine. This, thus, gives each DSN user direct control of his/hers data and prevents the social network provider from performing data mining analysis over these information. Unfortunately, the deployment of a personal DSN pod is not as simple as it sounds. Indeed, each pod’s owner has to maintain the security, integrity, and reliability of all the data stored in that provider. Furthermore, given the amount of data produced each day in a social network service, it is reasonable to assume that the majority of users cannot a↵ord the upkeep of an hardware capable of handling such amount of information. As a result, it has been shown that most of DSN users prefer to subscribe to an existing provider despite setting up a new one, bringing to an indirect centralization of data that leads DSNs to su↵er of the same issues as centralized social network services. In order to overcome this issue in this thesis we have investigated the possibility for DSN providers to lean on modern cloud-based storage services so as to o↵er a cloudbased information sharing service. This has required to deal with many challenges. As such, we have investigated the definition of cryptographic protocols enabling DSN users to securely store their resources in the public cloud, along with the definition of communication protocols ensuring that decryption keys are distributed only to authorized users, that is users that satisfy at least one of the access control policies specified by data owner according to Relationship-based access control model (RelBAC) [20, 34]. In addition, it has emerged that even DSN users have the same difficulties as OSN users in defining RelBAC rules that properly express their attitude towards their own privacy. Indeed, it is nowadays well accepted that the definition of access control policies is an error-prone task. Then, since misconfigured RelBAC policies may lead to harmful data release and may expose the privacy of others as well, we believe that DSN users should be assisted in the RelBAC policy definition process. At this purpose, we have designed a RelBAC policy recommendation system such that it can learn from DSN users their own attitude towards privacy, and exploits all the learned data to assist DSN users in the definition of RelBAC policies by suggesting customized privacy rules. Nevertheless, despite the presence of the above mentioned policy recommender, it is reasonable to assume that misconfigured RelBAC rules may appear in the system. However, rather than considering all misconfigured policies as leading to potentially harmful situations, we have considered that they might even lead to an exacerbated data restriction that brings to a loss of utility to DSN users. As an example, assuming that a low resolution and an high resolution version of the same picture are uploaded in the network, we believe that the low-res version should be granted to all those users who are granted to access the hi-res version, even though, due to a misconfiurated system, no policy explicitly authorizes them on the low-res picture. As such, we have designed a technique capable of exploiting all the existing data dependencies (i.e., any correlation between data) as a mean for increasing the system utility, that is, the number of queries that can be safely answered. Then, we have defined a query rewriting technique capable of extending defined access control policy authorizations by exploiting data dependencies, in order to authorize unauthorized but inferable data. In this thesis we present a complete description of the above mentioned proposals, along with the experimental results of the tests that have been carried out so as to verify the feasibility of the presented techniques