War Tools: Scan, Sniff, Spoof and Hijack
(Excerpted from
The Happy Hacker Book, Second and Third Editions)
"Hello, I don't mean to be rude, but I noticed you were examining
something, er... proprietary on our system. Would you mind explaining what you
were doing?"
Sigh. From time to time I get an email like that. Sometimes it is less
polite than this. In this case, I had been examining an intranet server. For
some reason it was directly accessible from the Internet instead of being on a
private internal network. I'll bet you can't reach that box from the Internet
any more:) I was just curious, not trying to break in!
The one thing that defines a hacker is curiosity: a blinding,
insatiable hunger for more, more, more information. If your objective is to
fight those who attack your computers, your curiosity will be your greatest
asset. This chapter covers some powerful war tools that can satisfy your
curiosity in a legal and constructive way -- and shows how to use them to
battle computer criminals.
Sysadmins tell me that it is far harder to keep people out of your
computer systems than it is to break in. In this chapter we will get a
glimpse of this war between sysadmins and computer intruders, and learn
something about the tools they both use.
In this chapter you will learn about: