SELinux Basics

SELinux is a Linux kernel security module providing mandatory access control, offering enhanced security beyond traditional permissions. It assigns security contexts to processes and objects, defining permitted actions based on a customizable policy. This policy dictates how processes interact with files, directories, and network ports. You can check SELinux status with `getenforce`, which will display Enforcing, Permissive, or Disabled. Enforcing actively blocks unauthorized actions, while Permissive logs violations without blocking. SELinux offers enhanced security, defense in depth, and granular control but also introduces complexity. Incorrect policies can restrict system functions, and troubleshooting can be challenging. It is a powerful tool for enhancing Linux security, particularly in sensitive environments. Effective implementation requires proper configuration and understanding of its principles. The enhanced protection offered often outweighs the challenges associated with its complexity.