UNIX and Linux System Administration Handbook, 5th Edition

3	Access Control and Rootly Powers

This chapter is about “access control,” as opposed to “security,” by which we mean that it focuses on the mechanical details of how the kernel and its delegates make security-related decisions. Chapter 27, Security, addresses the more general question of how to set up a system or network to minimize the chance of unwelcome access by intruders.

Access control is an area of active research, and it has long been one of the major challenges of operating system design. Over the last decade, UNIX and Linux have seen a Cambrian explosion of new options in this domain. A primary driver of this surge ...