Absolute OpenBSD—UNIX for the Practical Paranoid

by Michael W. Lucas

San Francisco

Copyright � 2003 by Michael W. Lucas.

All rights reserved. No part of this work may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval system, without the prior written permission of the copyright owner and the publisher.

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Library of Congress Cataloguing-in-Publication Data

Lucas, Michael W., 1967-
         Absolute OpenBSD: UNIX for the practical paranoid / Michael W. Lucas.
         p. cm.
Includes index.

ISBN 1-886411-99-9

1. OpenBSD (Electronic resource) 2. Operating systems (Computers) 3. UNIX (Computer file) I. Title.

QA76.9.O63L835 2003

005.4'32--dc21

2003000473

For Elizabeth, who brings spring's rich warm sunlight into darkest night

ACKNOWLEDGMENTS

OpenBSD is quite a trip, and the OpenBSD community even more so. Since starting this book, I've talked with more practical and professional paranoids than I knew existed outside of politics. It's been my privilege to work with some of the best computer security people in the world. Best of all, these people care about their work, and the impact it has on average people such as our parents and friends.

The following people all provided feedback on one or more chapters of this book, or answered specific questions on frequently-misunderstood aspects of OpenBSD, and as such deserve my heartfelt thanks. Some of them are OpenBSD crown princes, and others are just users who were trying to figure out what their computer was actually doing. What I've done right is thinks to them, and what I've done wrong is my own fault. They are, in alphabetical order: Shawn Carroll, Chris Cappuccio, Dave Feustel, Thorsten Glaser, Daniel Hartmeier, Jason Houx, Volker Kindermann, Anil Madhavapeddy, U.N. Owen (aka dreamwvr), Francisco Luis Roque, Srebrenko Sehic, Matt Simonsen, Sam Smith, Duncan Matthew Stirling, Peter Werner, and Jason Wright.

A special thanks goes out to Theo de Raadt, for taking time out of his fiendishly busy schedule to provide special insight into the innards of OpenBSD, for not holding back when I goofed, and especially for sticking to his standards of freedom, despite everything the world has to say on that subject.

When an author says something like, "Hold the presses! OpenBSD just added a whole slew of functionality and I have to rewrite huge sections of the book you were planning to ship out tomorrow," the editor is supposed to respond with dire threats involving chainsaws. The folks at No Starch just say, "Well, get to work then." I have been forced to report to the Secret Author Cabal that Bill and Karol are patient, kind, and thoughtful enough to resist our best techniques for driving publishers into Lovecraftian madness.

Then there's Sifu Brown and the fine staff and volunteers of the School of Chinese Martial Arts in Berkley, Michigan (http://www.ZenMartialArts.com). They have absolutely nothing to do with computers, but they have an awful lot to do with me not making dire threats involving chainsaws. Somehow, the Five Ways to Become a Great Martial Artist turned out to be the same as the Five Ways to Write a Great Computer Book — I just never knew it before.

And finally, for Liz, and not just for catching the pet rats before they can stash seeds in server cases.

Michael Lucas


Saint Clair Shores, MI


May 2003