👉 Overview
👀 What ?
AppArmor (Application Armor) is a mandatory access control (MAC) system for Linux. It is a kernel (core of the operating system) enhancement to confine programs to a limited set of resources. AppArmor's security model is to bind access control attributes to programs rather than to users.
🧐 Why ?
AppArmor is important as it provides a crucial layer of security for your system. It limits the potential damage from security vulnerabilities in applications by confining them to a set of predefined resources. This is particularly important for servers, where a single compromised application can potentially be used to attack other services and data.
⛏️ How ?
AppArmor can be implemented by creating profiles for applications. These profiles define the system resources the application can access and the operations it can perform. To take advantage of AppArmor, you should first install it using your distribution's package manager. Then, you can use tools like aa-genprof and aa-logprof to generate and manage profiles.
⏳ When ?
AppArmor was first included in the Linux kernel in 2007. It's now a standard part of many Linux distributions, including Ubuntu and openSUSE.
⚙️ Technical Explanations
At its core, AppArmor operates by defining a set of profiles that determine the resources an application can access. These profiles can be in 'enforce' mode, where violations are blocked and logged, or 'complain' mode, where violations are only logged. This makes it possible to test new profiles without risking system stability. AppArmor's profiles are easier to create and maintain than other MAC systems, as they can be generated from log files and do not require detailed understanding of the system's security policy. AppArmor provides a robust framework for limiting the potential damage of exploits, by confining applications to the minimum necessary set of permissions.