A caregiver support platform within the scope of an ambient assisted living ecosystem

The Ambient Assisted Living (AAL) area is in constant evolution, providing new technologies to users and enhancing the level of security and comfort that is ensured by house platforms. The Ambient Assisted Living for All (AAL4ALL) project aims to develop a new AAL concept, supported on a unified ecosystem and certification process that enables a heterogeneous environment. The concepts of Intelligent Environments, Ambient Intelligence, and the foundations of the Ambient Assisted Living are all presented in the framework of this project. In this work, we consider a specific platform developed in the scope of AAL4ALL, called UserAccess. The architecture of the platform and its role within the overall AAL4ALL concept, the implementation of the platform, and the available interfaces are presented. In addition, its feasibility is validated through a series of tests.Project “AAL4ALL”, co-financed by the European Community Fund FEDER, through COMPETE—Programa Operacional Factores de Competitividade (POFC). Foundation for Science and Technology (FCT), Lisbon, Portugal, through Project PEst-C/CTM/LA0025/2013. Project CAMCoF—Context-Aware Multimodal Communication Framework funded by ERDF—European Regional Development Fund through the COMPETE Programme (operational programme for competitiveness) and by National Funds through the FCT—Fundação para a Ciência e a Tecnologia (Portuguese Foundation for Science and Technology) within project FCOMP-01-0124-FEDER-028980. This work is part-funded by National Funds through the FCT - Fundação para a Ciência e a Tecnologia (Portuguese Foundation for Science and Technology) within project PEst-OE/EEI/UI0752/201

A FIREWALL MODEL OF FILE SYSTEM SECURITY

File system security is fundamental to the security of UNIX and Linux systems since in these systems almost everything is in the form of a file. To protect the system files and other sensitive user files from unauthorized accesses, certain security schemes are chosen and used by different organizations in their computer systems. A file system security model provides a formal description of a protection system. Each security model is associated with specified security policies which focus on one or more of the security principles: confidentiality, integrity and availability. The security policy is not only about “who” can access an object, but also about “how” a subject can access an object. To enforce the security policies, each access request is checked against the specified policies to decide whether it is allowed or rejected. The current protection schemes in UNIX/Linux systems focus on the access control. Besides the basic access control scheme of the system itself, which includes permission bits, setuid and seteuid mechanism and the root, there are other protection models, such as Capabilities, Domain Type Enforcement (DTE) and Role-Based Access Control (RBAC), supported and used in certain organizations. These models protect the confidentiality of the data directly. The integrity of the data is protected indirectly by only allowing trusted users to operate on the objects. The access control decisions of these models depend on either the identity of the user or the attributes of the process the user can execute, and the attributes of the objects. Adoption of these sophisticated models has been slow; this is likely due to the enormous complexity of specifying controls over a large file system and the need for system administrators to learn a new paradigm for file protection. We propose a new security model: file system firewall. It is an adoption of the familiar network firewall protection model, used to control the data that flows between networked computers, toward file system protection. This model can support decisions of access control based on any system generated attributes about the access requests, e.g., time of day. The access control decisions are not on one entity, such as the account in traditional discretionary access control or the domain name in DTE. In file system firewall, the access decisions are made upon situations on multiple entities. A situation is programmable with predicates on the attributes of subject, object and the system. File system firewall specifies the appropriate actions on these situations. We implemented the prototype of file system firewall on SUSE Linux. Preliminary results of performance tests on the prototype indicate that the runtime overhead is acceptable. We compared file system firewall with TE in SELinux to show that firewall model can accommodate many other access control models. Finally, we show the ease of use of firewall model. When firewall system is restricted to specified part of the system, all the other resources are not affected. This enables a relatively smooth adoption. This fact and that it is a familiar model to system administrators will facilitate adoption and correct use. The user study we conducted on traditional UNIX access control, SELinux and file system firewall confirmed that. The beginner users found it easier to use and faster to learn then traditional UNIX access control scheme and SELinux

Functionality-based application confinement: A parameterised and hierarchical approach to policy abstraction for rule-based application-oriented access controls

Access controls are traditionally designed to protect resources from users, and consequently make access decisions based on the identity of the user, treating all processes as if they are acting on behalf of the user that runs them. However, this user-oriented approach is insufficient at protecting against contemporary threats, where security compromises are often due to applications running malicious code, either due to software vulnerabilities or malware. Application-oriented access controls can mitigate this threat by managing the authority of individual applications. Rule-based application-oriented access controls can restrict applications to only allow access to the specific finely-grained resources required for them to carry out their tasks, and thus can significantly limit the damage that can be caused by malicious code. Unfortunately existing application-oriented access controls have policy complexity and usability problems that have limited their use. This thesis proposes a new access control model, known as functionality-based application confinement (FBAC). The FBAC model has a number of unique features designed to overcome problems with previous approaches. Policy abstractions, known as functionalities, are used to assign authority to applications based on the features they provide. Functionalities authorise elaborate sets of finely grained privileges based on high-level security goals, and adapt to the needs of specific applications through parameterisation. FBAC is hierarchical, which enables it to provide layers of abstraction and encapsulation in policy. It also simultaneously enforces the security goals of both users and administrators by providing discretionary and mandatory controls. An LSM-based (Linux security module) prototype implementation, known as FBAC-LSM, was developed as a proof-of-concept and was used to evaluate the new model and associated techniques. The policy requirements of over one hundred applications were analysed, and policy abstractions and application policies were developed. Analysis showed that the FBAC model is capable of representing the privilege needs of applications. The model is also well suited to automaiii tion techniques that can in many cases create complete application policies a priori, that is, without first running the applications. This is an improvement over previous approaches that typically rely on learning modes to generate policies. A usability study was conducted, which showed that compared to two widely-deployed alternatives (SELinux and AppArmor), FBAC-LSM had significantly higher perceived usability and resulted in significantly more protective policies. Qualitative analysis was performed and gave further insight into the issues surrounding the usability of application-oriented access controls, and confirmed the success of the FBAC model

Protecting Users From “Themselves”

Computer usage and threat models have changed drastically since the advent of access control systems in the 1960s. Instead of multiple users sharing a single file system, each user has many devices with their own storage. Thus, a user’s fear has shifted away from other users ’ impact on the same system to the threat of malice in the software they intentionally or even inadvertently run. As a result, we propose a new vision for access control: one where individual users are isolated by default and where the access of individual user applications is carefully managed. A key question is how much user administration effort would be required if a system implementing this vision were constructed. In this paper, we outline our work on just such a system, called PinUP, which manages file access on a per application basis for each user. We use historical data from our lab’s users to explore how much user and system administration effort is required. Since administration is required for user sharing in PinUP, we find that sharing via mail and file repositories requires a modest amount of administrative effort, a system policy change every couple of days and a small number of user administrative operations a day. We are encouraged that practical administration on such a scale is possible given an appropriate and secure user approach