ARE YOU A CRACKER OR A HACKER in Font

Encoder Code 3 of 9 in Font ARE YOU A CRACKER OR A HACKER

Linux users are often described as hackers. This doesn t mean they maliciously break into computers or write viruses. It s simply using the word hacker in its original sense from the 1970s, when it described a computer enthusiast who was interested in exploring the capabilities of computers. Many of the people behind multinational computing corporations started out as hackers. Examples are Steve Wozniak, a cofounder of Apple Computer, and Bill Joy, cofounder of Sun Microsystems. The word hacker is believed to derive from model train enthusiasts who hacked train tracks together as part of their hobby. When computing became popular in the early 1970s, several of these enthusiasts also became interested in computing, and the term was carried across with them. However, in recent years, the media has subverted the term hacker to apply to an individual who breaks into computer systems. This was based on ignorance, and many true hackers find the comparison extremely offensive. Because of this, the term cracker was invented to clearly define an individual who maliciously attacks computers. So, don t worry if an acquaintance describes herself as a Linux hacker, or tells you that she has spent the night hacking. Many Linux types use the term as a badge of honor.

Figure 9-1. Ordinary users are simply unable to modify or delete essential system files under Linux.

As you start to understand how Ubuntu works, you ll become more and more aware of commonsense methods that will protect your system. However, I ll outline a few of these now to get you started: Entering your password: Be very wary if you re asked to enter your password (outside of initial login, of course). You ll be asked to provide your password when following many of the configuration steps within this book, for example, and this is acceptable and safe. But if you re asked to do so out of the blue, then you should be suspicious. If the root password prompt dialog box (shown in Figure 9-2) appears when you run a file that shouldn t really need root permissions, such as an MP3 or OpenOffice.org file, you should treat the situation with caution.

Figure 9-2. Beware if you re asked to type your password out of the blue and for no apparent reason.

Installing new software: Be careful in choosing programs to download and install. Because Linux works on the basis of open-source code, anyone can theoretically tamper with a program, and then offer it for download by the unwary. This very rarely happens in real life. Even so, it s wise to avoid downloading programs from unofficial sources, such as web sites you find online via a search engine and whose authenticity you cannot totally trust. Instead, get software from the web site of the people who made it in the first place or, ideally, from the official Ubuntu software repositories (discussed in 8). Updating your system: Always ensure your system software is completely up-to-date. As with Windows, many Ubuntu programs have bugs that lead to security holes. Crackers target such vulnerabilities. Downloading the latest versions of Ubuntu software ensures that you not only get the latest features, but also that any critical security holes are patched. As with most versions of Linux, updating Ubuntu is easy and, of course, it s also free of charge. You ll learn how to get online updates in the next section. Locking up your PC: Limit who has physical access to your computer. Any Ubuntu system can be compromised by a simple floppy boot disk, or even the Ubuntu installation CD. Booting a PC using such disks gives anyone complete root access to your system s files, with no limitations. This is for obvious reasons; the idea of a boot disk is to let you fix your PC should something go wrong, and you cannot do this if you re blocked from accessing certain files. When Linux is used on servers that hold confidential data, it s not uncommon for the floppy and CD-ROM drives to be removed, thus avoiding booting via a boot disk. Such computers are also usually locked away in a room or even in a cupboard, denying physical access to the machine.