How TCP Wrappers Work
The TCP wrappers program is called in place of the actual service that it is to protect. There are two different methods for implementing TCP wrappers. The first is to simply replace the actual program with tcpd (the TCP wrappers daemon). Because this is a rather limited usage, and because the second method is more flexible, this chapter looks exclusively at the second implementation method—to have either the inetd metadaemon call tcpd for every invocation of a daemon, or to use tcpd within the /etc/hosts.allow file for certain patterns.
Some of the functionality of TCP wrappers is based on compile-time options. If you desire or require any of this functionality that is not built by default, you'll need to recompile, and ...
Get Special Edition Using Linux®, Sixth Edition now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
