Enforcing reputation constraints on business process workflows

The problem of trust in determining the flow of execution of business processes has been in the centre of research interst in the last decade as business processes become a de facto model of Internet-based commerce, particularly with the increasing popularity in Cloud computing. One of the main mea-sures of trust is reputation, where the quality of services as provided to their clients can be used as the main factor in calculating service and service provider reputation values. The work presented here contributes to the solving of this problem by defining a model for the calculation of service reputa-tion levels in a BPEL-based business workflow. These levels of reputation are then used to control the execution of the workflow based on service-level agreement constraints provided by the users of the workflow. The main contribution of the paper is to first present a formal meaning for BPEL processes, which is constrained by reputation requirements from the users, and then we demonstrate that these requirements can be enforced using a reference architecture with a case scenario from the domain of distributed map processing. Finally, the paper discusses the possible threats that can be launched on such an architecture

A Typed Model for Dynamic Authorizations

Security requirements in distributed software systems are inherently dynamic. In the case of authorization policies, resources are meant to be accessed only by authorized parties, but the authorization to access a resource may be dynamically granted/yielded. We describe ongoing work on a model for specifying communication and dynamic authorization handling. We build upon the pi-calculus so as to enrich communication-based systems with authorization specification and delegation; here authorizations regard channel usage and delegation refers to the act of yielding an authorization to another party. Our model includes: (i) a novel scoping construct for authorization, which allows to specify authorization boundaries, and (ii) communication primitives for authorizations, which allow to pass around authorizations to act on a given channel. An authorization error may consist in, e.g., performing an action along a name which is not under an appropriate authorization scope. We introduce a typing discipline that ensures that processes never reduce to authorization errors, even when authorizations are dynamically delegated.Comment: In Proceedings PLACES 2015, arXiv:1602.0325

Language-based Enforcement of User-defined Security Policies (As Applied to Multi-tier Web Programs)

Over the last 35 years, researchers have proposed many different forms of security policies to control how information is managed by software, e.g., multi-level information flow policies, role-based or history-based access control, data provenance management etc. A large body of work in programming language design and analysis has aimed to ensure that particular kinds of security policies are properly enforced by an application. However, these approaches typically fix the style of security policy and overall security goal, e.g., information flow policies with a goal of noninterference. This limits the programmer's ability to combine policy styles and to apply customized enforcement techniques while still being assured the system is secure. This dissertation presents a series of programming-language calculi each intended to verify the enforcement of a range of user-defined security policies. Rather than ``bake in'' the semantics of a particular model of security policy, our languages are parameterized by a programmer-provided specification of the policy and enforcement mechanism (in the form of code). Our approach relies on a novel combination of dependent types to correctly associate security policies with the objects they govern, and affine types to account for policy or program operations that include side effects. We have shown that our type systems are expressive enough to verify the enforcement of various forms of access control, provenance, information flow, and automata-based policies. Additionally, our approach facilitates straightforward proofs that programs implementing a particular policy achieve their high-level security goals. We have proved our languages sound and we have proved relevant security properties for each of the policies we have explored. To our knowledge, no prior framework enables the enforcement of such a wide variety of security policies with an equally high level of assurance. To evaluate the practicality of our solution, we have implemented one of our type systems as part of the Links web-programming language; we call the resulting language SELinks. We report on our experience using SELinks to build two substantial applications, a wiki and an on-line store, equipped with a combination of access control and provenance policies. In general, we have found the mechanisms SELinks provides to be both sufficient and relatively easy to use for many common policies, and that the modular separation of user-defined policy code permitted some reuse between the two applications

EPICS: A Framework for Enforcing Security Policies in Composite Web Services

With advances in cloud computing and the emergence of service marketplaces, the popularity of composite services marks a paradigm shift from single-domain monolithic systems to cross-domain distributed services, which raises important privacy and security concerns. Access control becomes a challenge in such systems because authentication, authorization and data disclosure may take place across endpoints that are not known to clients. The clients lack options for specifying policies to control the sharing of their data and have to rely on service providers which provide limited selection of security and privacy preferences. This lack of awareness and loss of control over data sharing increases threats to a client\u27s data and diminishes trust in these systems

EPICS: A Framework for Enforcing Security Policies in Composite Web Services

With advances in cloud computing and the emergence of service marketplaces, the popularity of composite services marks a paradigm shift from single-domain monolithic systems to cross-domain distributed services, which raises important privacy and security concerns. Access control becomes a challenge in such systems because authentication, authorization and data disclosure may take place across endpoints that are not known to clients. The clients lack options for specifying policies to control the sharing of their data and have to rely on service providers which offer limited selection of security and privacy preferences. This lack of awareness and loss of control over data sharing increases threats to a client's data and diminishes trust in these systems. We propose EPICS, an efficient and effective solution for enforcing security policies in composite Web services that protects data privacy throughout the service interaction lifecycle. The solution ensures that the data are distributed along with the client policies that dictate data access and an execution monitor that controls data disclosure. It empowers data owners with control of data disclosure decisions during interactions with remote services and reduces the risk of unauthorized access. The paper presents the design, implementation, and evaluation of the EPICS framework

An Overview of Automotive Service-Oriented Architectures and Implications for Security Countermeasures

New requirements from the customers\u27 and manufacturers\u27 point of view such as adding new software functions during the product life cycle require a transformed architecture design for future vehicles. The paradigm of signal-oriented communication established for many years will increasingly be replaced by service-oriented approaches in order to increase the update and upgrade capability. In this article, we provide an overview of current protocols and communication patterns for automotive architectures based on the service-oriented architecture (SOA) paradigm and compare them with signal-oriented approaches. Resulting challenges and opportunities of SOAs with respect to information security are outlined and discussed. For this purpose, we explain different security countermeasures and present a state of the section of automotive approaches in the fields of firewalls, Intrusion Detection Systems (IDSs) and Identity and Access Management (IAM). Our final discussion is based on an exemplary hybrid architecture (signal- and service-oriented) and examines the adaptation of existing security measures as well as their specific security features

Research Article Novel Security Conscious Evaluation Criteria for Web Service Composition

Abstract: This study aims to present a new mathematical based evaluation method for service composition with respects to security aspects. Web service composition as complex problem solver in service computing has become one of the recent challenging issues in today's web environment. It makes a new added value service through combination of available basic services to address the problem requirements. Despite the importance of service composition in service computing, security issues have not been addressed in this area. Considering the dazzling growth of number of service based transactions, making a secure composite service from candidate services with different security concerns is a demanding task. To deal with this challenge, different techniques have been employed which have direct impacts on secure service composition efficiency. Nonetheless, little work has been dedicated to deeply investigate those impacts on service composition outperformance. Therefore, the focus of this study is to evaluate the existing approaches based on their applied techniques and QoS aspects. A mathematicalbased security-aware evaluation framework is proposed wherein Analytic Hierarchy Process (AHP), a multiple criteria decision making technique, is adopted. The proposed framework is tested on state-of-the-art approaches and the statistical analysis of the results presents the efficiency and correctness of the proposed work