A Single Stack Multitasking Operating System for Resource Limited Embedded Devices
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AMNESIA 33: How TCP/IP Stacks Breed Critical Vulnerabilities in Iot
AMNESIA:33 | RESEARCH REPORT How TCP/IP Stacks Breed Critical Vulnerabilities in IoT, OT and IT Devices Published by Forescout Research Labs Written by Daniel dos Santos, Stanislav Dashevskyi, Jos Wetzels and Amine Amri RESEARCH REPORT | AMNESIA:33 Contents 1. Executive summary 4 2. About Project Memoria 5 3. AMNESIA:33 – a security analysis of open source TCP/IP stacks 7 3.1. Why focus on open source TCP/IP stacks? 7 3.2. Which open source stacks, exactly? 7 3.3. 33 new findings 9 4. A comparison with similar studies 14 4.1. Which components are typically flawed? 16 4.2. What are the most common vulnerability types? 17 4.3. Common anti-patterns 22 4.4. What about exploitability? 29 4.5. What is the actual danger? 32 5. Estimating the reach of AMNESIA:33 34 5.1. Where you can see AMNESIA:33 – the modern supply chain 34 5.2. The challenge – identifying and patching affected devices 36 5.3. Facing the challenge – estimating numbers 37 5.3.1. How many vendors 39 5.3.2. What device types 39 5.3.3. How many device units 40 6. An attack scenario 41 6.1. Other possible attack scenarios 44 7. Effective IoT risk mitigation 45 8. Conclusion 46 FORESCOUT RESEARCH LABS RESEARCH REPORT | AMNESIA:33 A note on vulnerability disclosure We would like to thank the CERT Coordination Center, the ICS-CERT, the German Federal Office for Information Security (BSI) and the JPCERT Coordination Center for their help in coordinating the disclosure of the AMNESIA:33 vulnerabilities. -
Performance Study of Real-Time Operating Systems for Internet Of
IET Software Research Article ISSN 1751-8806 Performance study of real-time operating Received on 11th April 2017 Revised 13th December 2017 systems for internet of things devices Accepted on 13th January 2018 E-First on 16th February 2018 doi: 10.1049/iet-sen.2017.0048 www.ietdl.org Rafael Raymundo Belleza1 , Edison Pignaton de Freitas1 1Institute of Informatics, Federal University of Rio Grande do Sul, Av. Bento Gonçalves, 9500, CP 15064, Porto Alegre CEP: 91501-970, Brazil E-mail: [email protected] Abstract: The development of constrained devices for the internet of things (IoT) presents lots of challenges to software developers who build applications on top of these devices. Many applications in this domain have severe non-functional requirements related to timing properties, which are important concerns that have to be handled. By using real-time operating systems (RTOSs), developers have greater productivity, as they provide native support for real-time properties handling. Some of the key points in the software development for IoT in these constrained devices, like task synchronisation and network communications, are already solved by this provided real-time support. However, different RTOSs offer different degrees of support to the different demanded real-time properties. Observing this aspect, this study presents a set of benchmark tests on the selected open source and proprietary RTOSs focused on the IoT. The benchmark results show that there is no clear winner, as each RTOS performs well at least on some criteria, but general conclusions can be drawn on the suitability of each of them according to their performance evaluation in the obtained results. -
What Is an Operating System III 2.1 Compnents II an Operating System
Page 1 of 6 What is an Operating System III 2.1 Compnents II An operating system (OS) is software that manages computer hardware and software resources and provides common services for computer programs. The operating system is an essential component of the system software in a computer system. Application programs usually require an operating system to function. Memory management Among other things, a multiprogramming operating system kernel must be responsible for managing all system memory which is currently in use by programs. This ensures that a program does not interfere with memory already in use by another program. Since programs time share, each program must have independent access to memory. Cooperative memory management, used by many early operating systems, assumes that all programs make voluntary use of the kernel's memory manager, and do not exceed their allocated memory. This system of memory management is almost never seen any more, since programs often contain bugs which can cause them to exceed their allocated memory. If a program fails, it may cause memory used by one or more other programs to be affected or overwritten. Malicious programs or viruses may purposefully alter another program's memory, or may affect the operation of the operating system itself. With cooperative memory management, it takes only one misbehaved program to crash the system. Memory protection enables the kernel to limit a process' access to the computer's memory. Various methods of memory protection exist, including memory segmentation and paging. All methods require some level of hardware support (such as the 80286 MMU), which doesn't exist in all computers. -
Mac OS X: an Introduction for Support Providers
Mac OS X: An Introduction for Support Providers Course Information Purpose of Course Mac OS X is the next-generation Macintosh operating system, utilizing a highly robust UNIX core with a brand new simplified user experience. It is the first successful attempt to provide a fully-functional graphical user experience in such an implementation without requiring the user to know or understand UNIX. This course is designed to provide a theoretical foundation for support providers seeking to provide user support for Mac OS X. It assumes the student has performed this role for Mac OS 9, and seeks to ground the student in Mac OS X using Mac OS 9 terms and concepts. Author: Robert Dorsett, manager, AppleCare Product Training & Readiness. Module Length: 2 hours Audience: Phone support, Apple Solutions Experts, Service Providers. Prerequisites: Experience supporting Mac OS 9 Course map: Operating Systems 101 Mac OS 9 and Cooperative Multitasking Mac OS X: Pre-emptive Multitasking and Protected Memory. Mac OS X: Symmetric Multiprocessing Components of Mac OS X The Layered Approach Darwin Core Services Graphics Services Application Environments Aqua Useful Mac OS X Jargon Bundles Frameworks Umbrella Frameworks Mac OS X Installation Initialization Options Installation Options Version 1.0 Copyright © 2001 by Apple Computer, Inc. All Rights Reserved. 1 Startup Keys Mac OS X Setup Assistant Mac OS 9 and Classic Standard Directory Names Quick Answers: Where do my __________ go? More Directory Names A Word on Paths Security UNIX and security Multiple user implementation Root Old Stuff in New Terms INITs in Mac OS X Fonts FKEYs Printing from Mac OS X Disk First Aid and Drive Setup Startup Items Mac OS 9 Control Panels and Functionality mapped to Mac OS X New Stuff to Check Out Review Questions Review Answers Further Reading Change history: 3/19/01: Removed comment about UFS volumes not being selectable by Startup Disk. -
A Tutorial on Performance Evaluation and Validation Methodology for Low-Power and Lossy Networks
A Tutorial on Performance Evaluation and Validation Methodology for Low-Power and Lossy Networks Kosmas Kritsis, Georgios Papadopoulos, Antoine Gallais, Periklis Chatzimisios, Fabrice Theoleyre To cite this version: Kosmas Kritsis, Georgios Papadopoulos, Antoine Gallais, Periklis Chatzimisios, Fabrice Theoleyre. A Tutorial on Performance Evaluation and Validation Methodology for Low-Power and Lossy Networks. Communications Surveys and Tutorials, IEEE Communications Society, Institute of Electrical and Electronics Engineers, 2018, 20 (3), pp.1799 - 1825. 10.1109/COMST.2018.2820810. hal-01886690 HAL Id: hal-01886690 https://hal.archives-ouvertes.fr/hal-01886690 Submitted on 23 Apr 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. 1 A Tutorial on Performance Evaluation and Validation Methodology for Low-Power and Lossy Networks Kosmas Kritsis, Georgios Z. Papadopoulos, Member, IEEE, Antoine Gallais, Periklis Chatzimisios, Senior Member, IEEE, and Fabrice Theoleyre,´ Senior Member, IEEE, Abstract—Envisioned communication densities in Internet of may be used for counting the number of vehicles, such to Things (IoT) applications are increasing continuously. Because control optimally the street traffic lights and to reduce the these wireless devices are often battery powered, we need waiting time [3]. specific energy efficient (low-power) solutions. -
CS 151: Introduction to Computers
Information Technology: Introduction to Computers Handout One Computer Hardware 1. Components a. System board, Main board, Motherboard b. Central Processing Unit (CPU) c. RAM (Random Access Memory) SDRAM. DDR-RAM, RAMBUS d. Expansion cards i. ISA - Industry Standard Architecture ii. PCI - Peripheral Component Interconnect iii. PCMCIA - Personal Computer Memory Card International Association iv. AGP – Accelerated Graphics Port e. Sound f. Network Interface Card (NIC) g. Modem h. Graphics Card (AGP – accelerated graphics port) i. Disk drives (A:\ floppy diskette; B:\ obsolete 5.25” floppy diskette; C:\Internal Hard Disk; D:\CD-ROM, CD-R/RW, DVD-ROM/R/RW (Compact Disk-Read Only Memory) 2. Peripherals a. Monitor b. Printer c. Keyboard d. Mouse e. Joystick f. Scanner g. Web cam Operating system – a collection of files and small programs that enables input and output. The operating system transforms the computer into a productive entity for human use. BIOS (Basic Input Output System) date, time, language, DOS – Disk Operating System Windows (Dual, parallel development for home and industry) Windows 3.1 Windows 3.11 (Windows for Workgroups) Windows 95 Windows N. T. (Network Technology) Windows 98 Windows N. T. 4.0 Windows Me Windows 2000 Windows XP Home Windows XP Professional The Evolution of Windows Early 80's IBM introduced the Personal PC using the Intel 8088 processor and Microsoft's Disk Operating System (DOS). This was a scaled down computer aimed at business which allowed a single user to execute a single program. Many changes have been introduced over the last 20 years to bring us to where we are now. -
A Comparative Study Between Operating Systems (Os) for the Internet of Things (Iot)
VOLUME 5 NO 4, 2017 A Comparative Study Between Operating Systems (Os) for the Internet of Things (IoT) Aberbach Hicham, Adil Jeghal, Abdelouahed Sabrim, Hamid Tairi LIIAN, Department of Mathematic & Computer Sciences, Sciences School, Sidi Mohammed Ben Abdellah University, [email protected], [email protected], [email protected], [email protected] ABSTRACT Abstract : We describe The Internet of Things (IoT) as a network of physical objects or "things" embedded with electronics, software, sensors, and network connectivity, which enables these objects to collect and exchange data in real time with the outside world. It therefore assumes an operating system (OS) which is considered as an unavoidable point for good communication between all devices “objects”. For this purpose, this paper presents a comparative study between the popular known operating systems for internet of things . In a first step we will define in detail the advantages and disadvantages of each one , then another part of Interpretation is developed, in order to analyze the specific requirements that an OS should satisfy to be used and determine the most appropriate .This work will solve the problem of choice of operating system suitable for the Internet of things in order to incorporate it within our research team. Keywords: Internet of things , network, physical object ,sensors,operating system. 1 Introduction The Internet of Things (IoT) is the vision of interconnecting objects, users and entities “objects”. Much, if not most, of the billions of intelligent devices on the Internet will be embedded systems equipped with an Operating Systems (OS) which is a system programs that manage computer resources whether tangible resources (like memory, storage, network, input/output etc.) or intangible resources (like running other computer programs as processes, providing logical ports for different network connections etc.), So it is the most important program that runs on a computer[1]. -
Real-Time Operating Systems with Example PICOS18
Real-Time Operating Systems With Example PICOS18 Sebastian Fischmeister 1 What is an Operating System? . A program that acts as an intermediary between a user of a computer and the computer hardware . Operating system goals: o Execute user programs and make solving user problems easier. o Make the computer system convenient to use . Use the computer hardware in an efficient manner CSE480/CIS700 S. Fischmeister 2 1 Computer System Components 1. Hardware – provides basic computing resources (CPU, memory, I/O devices) 2. Operating system – controls and coordinates the use of the hardware among the various application programs for the various users 3. Applications programs – define the ways in which the system resources are used to solve the computing problems of the users (compilers, database systems, video games, business programs) 4. Users (people, machines, other computers) CSE480/CIS700 S. Fischmeister 3 Abstract View of System Components CSE480/CIS700 S. Fischmeister 4 2 What is an RTOS? . Often used as a control device in a dedicated application such as controlling scientific experiments, medical imaging systems, industrial control systems, and some display systems . Well-defined fixed-time constraints CSE480/CIS700 S. Fischmeister 5 More Precisely? . The system allows access to sensitive resources with defined response times. o Maximum response times are good for hard real-time o Average response times are ok for soft real-time . Any system that provides the above can be classified as a real-time system o 10us for a context switch, ok? o 10s for a context switch, ok? CSE480/CIS700 S. Fischmeister 6 3 Taxonomy of RTOSs . -
Contiki – a Lightweight and Flexible Operating System for Tiny Networked Sensors
Contiki – a Lightweight and Flexible Operating System for Tiny Networked Sensors Adam Dunkels, Björn Grönvall, Thiemo Voigt Swedish Institute of Computer Science IEEE EmNetS-I, 16 November 2004 Sensor OS trade-offs: static vs dynamic event-driven vs multi-threaded What we have done ● Contiki – an OS for sensor network nodes ● Ported Contiki to a number of platforms ● MSP430, AVR, HC12, Z80, 6502, x86, ... ● Simulation environment for BSD/Linux/Windows ● Built a few applications for experimental network deployments Contributions ● Dynamic loading of programs ● Selective reprogramming ● Static vs dynamic linking ● Concurrency management mechanisms ● Events vs threads ● Trade-offs: preemption, size Contiki design target ● “Mote”-class device ● 10-100 kilobytes of code ROM ● 1-10 kilobytes of RAM ● Communication (radio) ● ESB from FU Berlin ● MSP430, 2k RAM, 60k ROM Contiki size (bytes) Module Code MSP430 Code AVR RAM Kernel 810 1044 10 + e + p Program loader 658 - 8 Multi-threading library 582 678 8 + s Timer library 60 90 0 Memory manager 170 226 0 Event log replicator 1656 1934 200 µIP TCP/IP stack 4146 5218 18 + b Run-time reprogramming and loadable programs Reprogramming sensor nodes ● Software development for sensor nets ● Need to reprogram many nodes quite often ● Utilize radio for reprogramming ● Radio inherently broadcast ● Reprogram many nodes at once ● Much faster than firmware download via cable or programming adapter ● Reprogram deployed networks Traditional systems: entire system a monolithic binary ● Most systems statically -
CS 450: Operating Systems Michael Lee <[email protected]>
The Process CS 450: Operating Systems Michael Lee <[email protected]> Agenda - The Process: what is it and what’s in it? - Forms of Multitasking - Tracking processes in the OS - Context switches and Scheduling - Process API a process is a program in execution - its behavior is largely defined by the program being executed - but a process is much more than just a program! Multitasking - Modern general-purpose OSes typically run dozens to hundreds of processes simultaneously - May collectively exceed capacity of hardware - Recall: virtualization allows each process to ignore physical hardware limitations and let OS take care of details CPU/Memory Virtualization - Time-slicing of CPU(s) is performed to simulate concurrency - Memory is partitioned and shared amongst processes - But per-process view is of a uniform address space - Lazy/On-demand loading of processes lowers total burden vs. “Batch” processing - Without multitasking, each program is run from start to finish without interruption from other processes - Including any I/O operations (which may be lengthy!) - Ensures minimal overhead (but at what cost?) - Is virtualization still necessary? Pros/Cons of Multitasking - Pro: may improve resource utilization if we can run some processes while others are blocking - Pro: makes process interaction possible - Con: virtualization introduces overhead (examples?) - Con: possibly reduced overall throughput Forms of Multitasking - Cooperative multitasking: processes voluntarily cede control - Preemptive multitasking: OS polices transitions (how?) - Real-time systems: hard, fixed time constraints (late is wrong!) What’s in a process? - Program (“text”) and data - Static/Stack/Heap memory contents - Registers (e.g., PC, SP, FP) - Open files and devices (e.g., network) - What else? Data vs. -
Scheduling Techniques for Reducing Processor Energy Use in Macos
Scheduling Techniques for Reducing Processor Energy Use in MacOS Jacob R. Lorch and Alan Jay Smith Computer Science Division, EECS Department, UC Berkeley Berkeley, CA 94720-1776 Abstract a number of engineering users. We found that, depending on the machine and user, up to 18±34% of total power was at- The CPU is one of the major power consumers in a tributable to components whose power consumption could be portable computer, and considerable power can be saved by reduced by power management of the processor, i.e. the CPU turning off the CPU when it is not doing useful work. In Ap- and logic that could be turned off when the CPU was inactive. ple's MacOS, however, idle time is often converted to busy This high percentage, combined with our intuition that soft- waiting, and generally it is very hard to tell when no use- ware power management could be signi®cantly improved for ful computation is occurring. In this paper, we suggest sev- the processor, led us to conclude that the most important tar- eral heuristic techniques for identifying this condition, and get for further research in software power management was for temporarily putting the CPU in a low-power state. These the processor. techniques include turning off the processor when all pro- Many modern microprocessors have low-power states, in cesses are blocked, turning off the processor when processes which they consume little or no power. To take advantage of appear to be busy waiting, and extending real time process such low-power states, the operating system needs to direct sleep periods. -
Embedded Operating Systems
7 Embedded Operating Systems Claudio Scordino1, Errico Guidieri1, Bruno Morelli1, Andrea Marongiu2,3, Giuseppe Tagliavini3 and Paolo Gai1 1Evidence SRL, Italy 2Swiss Federal Institute of Technology in Zurich (ETHZ), Switzerland 3University of Bologna, Italy In this chapter, we will provide a description of existing open-source operating systems (OSs) which have been analyzed with the objective of providing a porting for the reference architecture described in Chapter 2. Among the various possibilities, the ERIKA Enterprise RTOS (Real-Time Operating System) and Linux with preemption patches have been selected. A description of the porting effort on the reference architecture has also been provided. 7.1 Introduction In the past, OSs for high-performance computing (HPC) were based on custom-tailored solutions to fully exploit all performance opportunities of supercomputers. Nowadays, instead, HPC systems are being moved away from in-house OSs to more generic OS solutions like Linux. Such a trend can be observed in the TOP500 list [1] that includes the 500 most powerful supercomputers in the world, in which Linux dominates the competition. In fact, in around 20 years, Linux has been capable of conquering all the TOP500 list from scratch (for the first time in November 2017). Each manufacturer, however, still implements specific changes to the Linux OS to better exploit specific computer hardware features. This is especially true in the case of computing nodes in which lightweight kernels are used to speed up the computation. 173 174 Embedded Operating Systems Figure 7.1 Number of Linux-based supercomputers in the TOP500 list. Linux is a full-featured OS, originally designed to be used in server or desktop environments.