Novell APPARMOR 1.2 Instruction Manual

Novell AppArmor
Powered by
Immunix
Administration
Guide
www.novell.com
1.2 09/29/2005

Novell AppArmor Powered by Immunix 1.2 Administra-
tion Guide
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Contents
Introduction to Novell AppArmor vii
1Immunizing Programs 13
2Selecting Programs to Immunize 15
2.1 Immunize Programs That Grant Privilege . . . . . . . . . . . . . . . 15
2.2 Inspect Open Ports to Immunize Programs . . . . . . . . . . . . . . 16
3Building Novell AppArmor Proles 21
3.1 Prole Components and Syntax . . . . . . . . . . . . . . . . . . . 21
3.2 Building and Managing Novell AppArmor Proles . . . . . . . . . . . 24
3.3 Building Novell AppArmor Proles with the YaST GUI . . . . . . . . . . 26
3.4 Building Novell AppArmor Proles Using the Command Line Interface . . 49
3.5 Two Methods of Proling . . . . . . . . . . . . . . . . . . . . . . 54
3.6 Pathnames and Globbing . . . . . . . . . . . . . . . . . . . . . . 73
3.7 File Permission Access Modes . . . . . . . . . . . . . . . . . . . . 74
4Managing Proled Applications 77
4.1 Monitoring Your Secured Applications . . . . . . . . . . . . . . . . 77
4.2 Setting Up Event Notication . . . . . . . . . . . . . . . . . . . . 78
4.3 Reports............................. 81
4.4 Reacting to Security Events . . . . . . . . . . . . . . . . . . . . 102
4.5 Maintaining Your Security Proles . . . . . . . . . . . . . . . . . 103
5Proling Your Web Applications Using ChangeHat Apache 105
5.1 ApacheChangeHat........................ 106

5.2 Apache Conguration for mod_change_hat . . . . . . . . . . . . . 113
6Support 117
6.1 Updating Novell AppArmor Online . . . . . . . . . . . . . . . . . 117
6.2 Using the Man Pages . . . . . . . . . . . . . . . . . . . . . . . 117
6.3 For More Information . . . . . . . . . . . . . . . . . . . . . . 119
6.4 Troubleshooting......................... 119
6.5 Support for SUSE Linux . . . . . . . . . . . . . . . . . . . . . . 121
6.6 Reporting Bugs for AppArmor . . . . . . . . . . . . . . . . . . . 126
Glossary 129
vi

Introduction to Novell
AppArmor
Novell® AppArmor Powered by Immunix is designed to provide easy-to-use application
security for both servers and workstations. Novell AppArmor is an access control system
that lets you specify per program which les the program may read, write, and execute.
AppArmor secures applications by enforcing good application behavior without relying
on attack signatures, so can prevent attacks even if they are exploiting previously un-
known vulnerabilities.
Novell AppArmor consists of:
• A library of AppArmor proles for common Linux* applications describing what
les the program needs to access.
• A library of AppArmor prole foundation classes (prole building blocks) needed
for common application activities, such as DNS lookup and user authentication.
• A tool suite for developing and enhancing AppArmor proles, so that you can
change the existing proles to suit your needs and create new proles for your own
local and custom applications.
• Several specially modied applications that are AppArmor enabled to provide en-
hanced security in the form of unique subprocess connement, including Apache.
• The Novell AppArmor–loadable kernel module and associated control scripts to
enforce AppArmor policies on your SUSE® Linux system.
NOTE
Some distributions of SUSE Linux include a version of AppArmor that enforce
policies for a limited set of programs. These policies can be modied to suit
your particular environment using the included AppArmor tool set. To create
AppArmor proles for additional programs, an upgrade to the full version of
AppArmor is required.

1 Documentation Conventions
The following typographical conventions are used in this manual:
Menu Items, Field Names, and Screen Titles in GUIs
When using GUIs, eld names, menu and screen titles, and eld values are shown
as File.
Keys
Key names are listed as they appear on your keyboard, as in Enter and Esc .
Command
Linux commands (and other operating system commands, when used) are repre-
sented this way. This style should indicate to you that you can type the word
or phrase on the command line and press Enter to run the command.
Example 1 Command Environment
To use ls to view the contents in the current directory, enter ls in a terminal
window.
Filename
Filenames, directory names, paths, and RPM package names are represented this
way. This style should indicate that a particular le or directory exists by that name
on your Linux system.
Placeholders
Replace placeholder with the actual value that matches your setup.
Examples, Notes, and Warnings
Examples use Example: when appropriate. Notes and pertinent information are
shown with a Note or Warning ag, as in:
NOTE
Notes highlight information that might help better understand previous
paragraphs. Warnings provide important information that might seriously
affect the integrity of the product or your data.
viii

Computer Output
When you see text in this style, it indicates text displayed by the computer
on the command line. You see responses to typed commands, error messages, and
interactive prompts for your input during scripts or programs shown this way.
Example 2 Computer Output
Use the ls command to display the contents of a directory:
$ ls
Desktop about.html logs
Mail backupfiles mail
Trademarks
A trademark symbol (®, etc.) denotes a Novell trademark. An asterisk (*) denotes
a third-party trademark.
2 Understanding This Guide
Immunizing Programs
Describes operation of Novell AppArmor Powered by Immunix.
Selecting Programs to Immunize
Describes the types of programs that should have Novell AppArmor proles created
for them.
Building Novell AppArmor Proles
Describes how to use the Novell AppArmor tools to immunize your own programs
and third-party programs that you may have installed on your SUSE Linux system.
It also helps you to add, edit, or delete proles that have been created for your ap-
plications.
Managing Proled Applications
Describes how to perform Novell AppArmor prole maintenance, which involves
tracking common issues and concerns.
Proling Your Web Applications Using ChangeHat Apache
Enables you to create subproles for the Apache Web server that allow you to
tightly conne small sections of Web application processing.
Introduction to Novell AppArmor ix

Support
Indicates support options for this product.
Glossary
Provides a list of terms and their denitions.
3 Getting Started with Novell
AppArmor
Novell AppArmor Powered by Immunix (Novell AppArmor) provides you with tech-
nologies to protect your applications from their own vulnerabilities by creating Novell
AppArmor proles for applications on your SUSE Linux system.
3.1 Launching Novell AppArmor through
the YaST GUI
SUSE Linux offers the utility YaST. Using YaST, you can launch the Novell AppArmor
interface. This is the recommended method for a novice Linux user. For the other
available methods, refer to Section 3.2, “Building and Managing Novell AppArmor
Proles” (page 24).
•To start YaST, select System →Control Center (YaST) from the SUSE menu.
YaST is launched as shown in Section 3.2, “Novell AppArmor Basics” (page x),
below. You can refer to this section to navigate in Novell AppArmor.
NOTE
Alternately, you can launch the YaST GUI by opening a terminal window then
entering yast2 while logged in as root.
3.2 Novell AppArmor Basics
Novell AppArmor enables you to manage proles through a simple user interface.
x