Hacking Linux-Powered Devices.pdf

Hacking Linux-Powered

Devices

Stefan Arentz

<stefan@soze.com>

Part I

Introduction

What is Embedded Linux?

Embedded usually means that it is a device

with limited and specialized capabilities. It is

not a ‘personal computer’ as your laptop or

PC on your desk.

Embedded Linux means that there is a Linux

kernel running on such a device.

Usually together with a combination of

proprietary software and other OSS

components running on top of that kernel.

(The “user space” parts.)

Example: an imaginary portable

DivX player

(From a Linux POV)

Hardware: CPU, RAM, Flash card, screen, bunch of buttons.

Process listing of an imaginary portable DivX player

PID Uid VmSize Stat Command

1 0 396 S init

2 0 4829 S mplayer

This could be a real world example, sometimes it really is

this simple.

Some Real Examples of

Linux-Powered Devices