Special Edition Using Linux®, Sixth Edition

What Are TCP Wrappers?

A wrapper is something that is put around something else to protect it or modify its environment. TCP wrappers are put around server programs to help protect the host from exploit using that program, or to track abusers as they access the programs in an attempt to circumvent security safeguards. Although not a foolproof method of preventing intrusions, TCP wrappers do provide good early warning—via system logging—of possible intrusion attempts, and they are one more piece of the puzzle used to prevent subsequent intrusions and to track intruders back to their source.

Note

On the intrusion early warning and prevention side, you'll look at TCP wrappers—what they are, how they work, and how to configure this facility. Because ...