Linux Security

In: Computers and Technology

Submitted By bknow55
Words 942
Pages 4
| Linux Security | A review of some current technologies | | | |

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In the pre-Internet world you have criminals looking for “hard” assets: money, jewelry and other items that could be easily turned into hard currency. We have always had “white-collar” crime such as embezzlement, fraud and insider trading. With the proliferation of the Internet and our personal and professional lives stored in the cloud; criminals can now take one ubiquitous piece of information and turn themselves into a whole other person. The ease in which such information can be used has turned people who would never think of ever holding up a bank, mugging someone or other physical crime, into criminals. This type crime has spawned a whole new “industry”: cyber security. One of the most important aspects of a network administrator’s job is to secure the system from any person who wishes to do criminal activities. These people are both within and outside the organization. With the Linux system there are three main technologies that are in use today. They are SELinux, chroot jail, and iptables.
The first line of defense in a Linux system is chroot jail. Chroot is a process or application that changes the root directory for a user. To the user it appears that they are in their root directory, but they are actually in a modified root directory. This modified root directory is called jail.
Without a chroot jail, a user with limited file permissions would still be able to navigate to top-level directories. As an example, suppose the user’s directory is /home/user. Without chroot, nothing would prevent the user from navigating up to /home to see other users’ directories or even navigating up to / where they can see /etc, /usr, /var, /lib, and other system-critical directories. Although the user would not have the permissions to edit them, they would be able to see the…...

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