LPIC I Exam Cram™ 2: Linux Professional Institute Certification Exams 101 and 102

Chapter 19. Security

Terms you’ll need to understand:

✓	Chain
✓	Firewall
✓	Host security
✓	Masquerade
✓	Rule
✓	Secure shell
✓	TCP wrappers

Techniques you’ll need to master:

✓	Configuring hosts for security
✓	Setting and changing user password options
✓	Finding security risks
✓	Verifying package authenticity
✓	Configuring basic ipchains
✓	Configuring basic iptables
✓	Viewing current iptables’ configurations
✓	Setting up and configuring SSH
✓	Signing in, copying files, and setting boot options for SSH

Using TCP Wrappers to Secure a Service

Though covered in detail elsewhere, TCP wrappers are an important part of system security and require a quick review.

The majority of system services or daemons use the libwrap.a library for TCP wrappers functionality. The concept of TCP wrappers ...