This chapter will provide a basic introduction to system security concepts, some
general good rules of thumb, and some advanced topics under FreeBSD. A lot of the topics
covered here can be applied to system and Internet security in general as well. The
Internet is no longer a ``friendly'' place in which everyone wants to be your kind
neighbor. Securing your system is imperative to protect your data, intellectual property,
time, and much more from the hands of hackers and the like.
FreeBSD provides an array of utilities and mechanisms to ensure the integrity and
security of your system and network.
After reading this chapter, you will know:
Basic system security concepts, in respect to FreeBSD.
About the various crypt mechanisms available in FreeBSD, such as DES and MD5.
How to set up one-time password authentication.
How to set up KerberosIV on FreeBSD releases prior to
How to set up Kerberos5 on post FreeBSD 5.0 releases.
How to create firewalls using IPFW.
How to configure IPsec and create a VPN between
How to configure and use OpenSSH, FreeBSD's SSH implementation.
How to configure and load access control extension modules using the TrustedBSD
What file system ACLs are and how to use them.
How to utililize the FreeBSD security advisories publications.
Before reading this chapter, you should: