Scalability of Microkernel-Based Systems
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Automatic Sandboxing of Unsafe Software Components in High Level Languages
Master Thesis Automatic Sandboxing of Unsafe Software Components in High Level Languages Benjamin Lamowski Technische Universität Dresden Fakultät Informatik Institut für Systemarchitektur Professur Betriebssysteme Betreuender Hochschullehrer: Prof. Dr. rer. nat. Hermann Härtig Betreuender Mitarbeiter: Dr. Carsten Weinhold 3. Mai 2017 Aufgabenstellung Neue “sichere“ Programmiersprachen wie Go, Swift oder Rust wurden nicht nur für die normale Anwendungsentwicklung entworfen, sondern sie zielen auch auf eine hochper- formante Ausführung und Programmierung vergleichsweise systemnaher Funktionalität ab. Eine attraktive Eigenschaft beispielsweise von Rust ist das gegenüber C und C++ deutlich strengere Speicherverwaltungsmodell, bei dem bereits zur Kompilierzeit der Lebenszyklus und die Erreichbarkeit von Objekten sowie die Zuständigkeit für deren Allokation und Deallokation wohldefiniert sind. Ganze Klassen von Programmfehlern wie etwa Buffer Overflows oder Dereferenzierung ungültige Zeiger werden dadurch eliminiert und die Programme mithin sicherer und robuster. Aus diversen Gründen müssen Programme, die in sicheren Sprachen geschriebenen wurden, aber oftmals auf “unsicheren“ Legacy-Code zurückgreifen. So bietet etwa Rust über das “unsafe“-Sprachelement die Möglichkeit, Funktionen innerhalb von Bibliotheken aufzurufen, die in fehleranfälligem C geschrieben sind. Leider werden die vom Com- piler durchgesetzten Garantien der sicheren Sprache hinfällig, sobald im Code einer C-Bibliothek ein Speicherfehler auftritt. Ein Schreibzugriff etwa durch -
A Programmable Microkernel for Real-Time Systems∗
A Programmable Microkernel for Real-Time Systems∗ Christoph M. Kirsch Marco A.A. Sanvido Thomas A. Henzinger University of Salzburg VMWare Inc. EPFL and UC Berkeley [email protected] tah@epfl.ch ABSTRACT Categories and Subject Descriptors We present a new software system architecture for the im- D.4.7 [Operating Systems]: Organization and Design— plementation of hard real-time applications. The core of the Real-time systems and embedded systems system is a microkernel whose reactivity (interrupt handling as in synchronous reactive programs) and proactivity (task General Terms scheduling as in traditional RTOSs) are fully programma- Languages ble. The microkernel, which we implemented on a Strong- ARM processor, consists of two interacting domain-specific Keywords virtual machines, a reactive E (Embedded) machine and a proactive S (Scheduling) machine. The microkernel code (or Real Time, Operating System, Virtual Machine microcode) that runs on the microkernel is partitioned into E and S code. E code manages the interaction of the system 1. INTRODUCTION with the physical environment: the execution of E code is In [9], we advocated the E (Embedded) machine as a triggered by environment interrupts, which signal external portable target for compiling hard real-time code, and in- events such as the arrival of a message or sensor value, and it troduced, in [11], the S (Scheduling) machine as a universal releases application tasks to the S machine. S code manages target for generating schedules according to arbitrary and the interaction of the system with the processor: the exe- possibly non-trivial strategies such as nonpreemptive and cution of S code is triggered by hardware interrupts, which multiprocessor scheduling. -
A Microkernel API for Fine-Grained Decomposition
A Microkernel API for Fine-Grained Decomposition Sebastian Reichelt Jan Stoess Frank Bellosa System Architecture Group, University of Karlsruhe, Germany freichelt,stoess,[email protected] ABSTRACT from the microkernel APIs in existence. The need, for in- Microkernel-based operating systems typically require spe- stance, to explicitly pass messages between servers, or the cial attention to issues that otherwise arise only in dis- need to set up threads and address spaces in every server for tributed systems. The resulting extra code degrades per- parallelism or protection require OS developers to adopt the formance and increases development effort, severely limiting mindset of a distributed-system programmer rather than to decomposition granularity. take advantage of their knowledge on traditional OS design. We present a new microkernel design that enables OS devel- Distributed-system paradigms, though well-understood and opers to decompose systems into very fine-grained servers. suited for physically (and, thus, coarsely) partitioned sys- We avoid the typical obstacles by defining servers as light- tems, present obstacles to the fine-grained decomposition weight, passive objects. We replace complex IPC mecha- required to exploit the benefits of microkernels: First, a nisms by a simple function-call approach, and our passive, lot of development effort must be spent into matching the module-like server model obviates the need to create threads OS structure to the architecture of the selected microkernel, in every server. Server code is compiled into small self- which also hinders porting existing code from monolithic sys- contained files, which can be loaded into the same address tems. Second, the more servers exist | a desired property space (for speed) or different address spaces (for safety). -
A Practical UNIX Capability System
A Practical UNIX Capability System Adam Langley <[email protected]> 22nd June 2005 ii Abstract This report seeks to document the development of a capability security system based on a Linux kernel and to follow through the implications of such a system. After defining terms, several other capability systems are discussed and found to be excellent, but to have too high a barrier to entry. This motivates the development of the above system. The capability system decomposes traditionally monolithic applications into a number of communicating actors, each of which is a separate process. Actors may only communicate using the capabilities given to them and so the impact of a vulnerability in a given actor can be reasoned about. This design pattern is demonstrated to be advantageous in terms of security, comprehensibility and mod- ularity and with an acceptable performance penality. From this, following through a few of the further avenues which present themselves is the two hours traffic of our stage. Acknowledgments I would like to thank my supervisor, Dr Kelly, for all the time he has put into cajoling and persuading me that the rest of the world might have a trick or two worth learning. Also, I’d like to thank Bryce Wilcox-O’Hearn for introducing me to capabilities many years ago. Contents 1 Introduction 1 2 Terms 3 2.1 POSIX ‘Capabilities’ . 3 2.2 Password Capabilities . 4 3 Motivations 7 3.1 Ambient Authority . 7 3.2 Confused Deputy . 8 3.3 Pervasive Testing . 8 3.4 Clear Auditing of Vulnerabilities . 9 3.5 Easy Configurability . -
The Design of the EMPS Multiprocessor Executive for Distributed Computing
The design of the EMPS multiprocessor executive for distributed computing Citation for published version (APA): van Dijk, G. J. W. (1993). The design of the EMPS multiprocessor executive for distributed computing. Technische Universiteit Eindhoven. https://doi.org/10.6100/IR393185 DOI: 10.6100/IR393185 Document status and date: Published: 01/01/1993 Document Version: Publisher’s PDF, also known as Version of Record (includes final page, issue and volume numbers) Please check the document version of this publication: • A submitted manuscript is the version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal. -
The Design and Implementation of Multiprocessor Support for an Industrial Operating System Kernel
Blekinge Institute of Technology Research Report 2005:06 The Design and Implementation of Multiprocessor Support for an Industrial Operating System Kernel Simon Kågström Håkan Grahn Lars Lundberg Department of Systems and Software School of Engineering Blekinge Institute of Technology The Design and Implementation of Multiprocessor Support for an Industrial Operating System Kernel Simon Kågström, Håkan Grahn, and Lars Lundberg Department of Systems and Software Engineering School of Engineering Blekinge Institute of Technology P.O. Box 520, SE-372 25 Ronneby, Sweden {ska, hgr, llu}@bth.se Abstract The ongoing transition from uniprocessor to multiprocessor computers requires support from the op- erating system kernel. Although many general-purpose multiprocessor operating systems exist, there is a large number of specialized operating systems which require porting in order to work on multipro- cessors. In this paper we describe the multiprocessor port of a cluster operating system kernel from a producer of industrial systems. Our initial implementation uses a giant locking scheme that serializes kernel execution. We also employed a method in which CPU-local variables are placed in a special sec- tion mapped to per-CPU physical memory pages. The giant lock and CPU-local section allowed us to implement an initial working version with only minor changes to the original code, although the giant lock and kernel-bound applications limit the performance of our multiprocessor port. Finally, we also discuss experiences from the implementation. 1 Introduction A current trend in the computer industry is the transition from uniprocessors to various kinds of multipro- cessors, also for desktop and embeddedsystems. Apart from traditional SMP systems, many manufacturers are now presenting chip multiprocessors or simultaneous multithreaded CPUs [9, 15, 16] which allow more efficient use of chip area. -
Chapter 1. Origins of Mac OS X
1 Chapter 1. Origins of Mac OS X "Most ideas come from previous ideas." Alan Curtis Kay The Mac OS X operating system represents a rather successful coming together of paradigms, ideologies, and technologies that have often resisted each other in the past. A good example is the cordial relationship that exists between the command-line and graphical interfaces in Mac OS X. The system is a result of the trials and tribulations of Apple and NeXT, as well as their user and developer communities. Mac OS X exemplifies how a capable system can result from the direct or indirect efforts of corporations, academic and research communities, the Open Source and Free Software movements, and, of course, individuals. Apple has been around since 1976, and many accounts of its history have been told. If the story of Apple as a company is fascinating, so is the technical history of Apple's operating systems. In this chapter,[1] we will trace the history of Mac OS X, discussing several technologies whose confluence eventually led to the modern-day Apple operating system. [1] This book's accompanying web site (www.osxbook.com) provides a more detailed technical history of all of Apple's operating systems. 1 2 2 1 1.1. Apple's Quest for the[2] Operating System [2] Whereas the word "the" is used here to designate prominence and desirability, it is an interesting coincidence that "THE" was the name of a multiprogramming system described by Edsger W. Dijkstra in a 1968 paper. It was March 1988. The Macintosh had been around for four years. -
Improving Learning of Programming Through E-Learning by Using Asynchronous Virtual Pair Programming
Improving Learning of Programming Through E-Learning by Using Asynchronous Virtual Pair Programming Abdullah Mohd ZIN Department of Industrial Computing Faculty of Information Science and Technology National University of Malaysia Bangi, MALAYSIA Sufian IDRIS Department of Computer Science Faculty of Information Science and Technology National University of Malaysia Bangi, MALAYSIA Nantha Kumar SUBRAMANIAM Open University Malaysia (OUM) Faculty of Information Technology and Multimedia Communication Kuala Lumpur, MALAYSIA ABSTRACT The problem of learning programming subjects, especially through distance learning and E-Learning, has been widely reported in literatures. Many attempts have been made to solve these problems. This has led to many new approaches in the techniques of learning of programming. One of the approaches that have been proposed is the use of virtual pair programming (VPP). Most of the studies about VPP in distance learning or e-learning environment focus on the use of the synchronous mode of collaboration between learners. Not much research have been done about asynchronous VPP. This paper describes how we have implemented VPP and a research that has been carried out to study the effectiveness of asynchronous VPP for learning of programming. In particular, this research study the effectiveness of asynchronous VPP in the learning of object-oriented programming among students at Open University Malaysia (OUM). The result of the research has shown that most of the learners have given positive feedback, indicating that they are happy with the use of asynchronous VPP. At the same time, learners did recommend some extra features that could be added in making asynchronous VPP more enjoyable. Keywords: Pair-programming; Virtual Pair-programming; Object Oriented Programming INTRODUCTION Delivering program of Information Technology through distance learning or E- Learning is indeed a very challenging task. -
The Joe-E Language Specification (Draft)
The Joe-E Language Specification (draft) Adrian Mettler David Wagner famettler,[email protected] February 3, 2008 Disclaimer: This is a draft version of the Joe-E specification, and is subject to change. Sections 5 - 7 mention some (but not all) of the aspects of the Joe-E language that are future work or current works in progress. 1 Introduction We describe the Joe-E language, a capability-based subset of Java intended to make it easier to build secure systems. The goal of object capability languages is to support the Principle of Least Authority (POLA), so that each object naturally receives the least privilege (i.e., least authority) needed to do its job. Thus, we hope that Joe-E will support secure programming while remaining familiar to Java programmers everywhere. 2 Goals We have several goals for the Joe-E language: • Be familiar to Java programmers. To minimize the barriers to adoption of Joe-E, the syntax and semantics of Joe-E should be familiar to Java programmers. We also want Joe-E programmers to be able to use all of their existing tools for editing, compiling, executing, debugging, profiling, and reasoning about Java code. We accomplish this by defining Joe-E as a subset of Java. In general: Subsetting Principle: Any valid Joe-E program should also be a valid Java program, with identical semantics. This preserves the semantics Java programmers will expect, which are critical to keeping the adoption costs manageable. Also, it means all of today's Java tools (IDEs, debuggers, profilers, static analyzers, theorem provers, etc.) will apply to Joe-E code. -
Filesystem Performance on Freebsd
Filesystem Performance on FreeBSD Kris Kennaway [email protected] BSDCan 2006, Ottawa, May 12 Introduction ● Filesystem performance has many aspects ● No single metric for quantifying it ● I will focus on aspects that are relevant for my workloads (concurrent package building) ● The main relevant filesystem workloads seem to be – Concurrent tarball extraction – Recursive filesystem traversals ● Aim: determine relative performance of FreeBSD 4.x, 5.x and 6.x on these workloads – Overall performance and SMP scaling – Evaluate results of multi-year kernel locking strategy as it relates to these workloads Outline ● SMP architectural differences between 4/5/6.x ● Test methodology ● Hardware used ● Parallel tarball extraction test – Disk array and memory disk ● Scaling beyond 4 CPUs ● Recursive filesystem traversal test ● Conclusions & future work SMP Architectural Overview ● FreeBSD 4.x; rudimentary SMP support – Giant kernel lock restricts kernel access to one process at a time – SPL model; interrupts may still be processed in parallel ● FreeBSD 5.x; aim towards greater scalability – Giant-locked to begin with; then finer-grained locking pushdown ● FreeBSD 5.3; VM Giant-free ● FreeBSD 5.4; network stack Giant-free (mostly) ● Many other subsystems/drivers also locked – Interrupts as kernel threads; compete for common locks (if any) with everything else ● FreeBSD 6.x; – Consolidation; further pushdown; payoff! – VFS subsystem, UFS filesystem Giant-free FreeBSD versions ● FreeBSD 4.11-STABLE (11/2005) – Needed for amr driver fixes after 4.11-RELEASE ● FreeBSD 5.4-STABLE (11/05) – No patches needed ● FreeBSD 6.0-STABLE (11/05) – patches: ● Locking reworked in amr driver by Scott Long for better performance ● All relevant changes merged into FreeBSD 6.1 – A kernel panic was encountered at very high I/O loads ● Also fixed in 6.1 Test aims and Methodology ● Want to measure – overall performance difference between FreeBSD branches under varying (concurrent process I/O) loads – scaling to multiple CPUs ● Avoid saturating hardware resources (e.g. -
Access Control and Operating System
Outline (may not finish in one lecture) Access Control and Operating Access Control Concepts Secure OS System Security • Matrix, ACL, Capabilities • Methods for resisting • Multi-level security (MLS) stronger attacks OS Mechanisms Assurance • Multics • Orange Book, TCSEC John Mitchell – Ring structure • Common Criteria • Amoeba • Windows 2000 – Distributed, capabilities certification • Unix Some Limitations – File system, Setuid • Information flow • Windows • Covert channels – File system, Tokens, EFS • SE Linux – Role-based, Domain type enforcement Access control Access control matrix [Lampson] Common Assumption Objects • System knows who the user is File 1 File 2 File 3 … File n – User has entered a name and password, or other info • Access requests pass through gatekeeper User 1 read write - - read – OS must be designed monitor cannot be bypassed User 2 write write write - - Reference Subjects monitor User 3 - - - read read User process ? Resource … User m read write read write read Decide whether user can apply operation to resource Two implementation concepts Capabilities Access control list (ACL) File 1 File 2 … Operating system concept • “… of the future and always will be …” • Store column of matrix User 1 read write - Examples with the resource User 2 write write - • Dennis and van Horn, MIT PDP-1 Timesharing Capability User 3 - - read • Hydra, StarOS, Intel iAPX 432, Eros, … • User holds a “ticket” for … • Amoeba: distributed, unforgeable tickets each resource User m read write write • Two variations References – store -
Research Purpose Operating Systems – a Wide Survey
GESJ: Computer Science and Telecommunications 2010|No.3(26) ISSN 1512-1232 RESEARCH PURPOSE OPERATING SYSTEMS – A WIDE SURVEY Pinaki Chakraborty School of Computer and Systems Sciences, Jawaharlal Nehru University, New Delhi – 110067, India. E-mail: [email protected] Abstract Operating systems constitute a class of vital software. A plethora of operating systems, of different types and developed by different manufacturers over the years, are available now. This paper concentrates on research purpose operating systems because many of them have high technological significance and they have been vividly documented in the research literature. Thirty-four academic and research purpose operating systems have been briefly reviewed in this paper. It was observed that the microkernel based architecture is being used widely to design research purpose operating systems. It was also noticed that object oriented operating systems are emerging as a promising option. Hence, the paper concludes by suggesting a study of the scope of microkernel based object oriented operating systems. Keywords: Operating system, research purpose operating system, object oriented operating system, microkernel 1. Introduction An operating system is a software that manages all the resources of a computer, both hardware and software, and provides an environment in which a user can execute programs in a convenient and efficient manner [1]. However, the principles and concepts used in the operating systems were not standardized in a day. In fact, operating systems have been evolving through the years [2]. There were no operating systems in the early computers. In those systems, every program required full hardware specification to execute correctly and perform each trivial task, and its own drivers for peripheral devices like card readers and line printers.