#SELinux

2 posts

RHEL Advanced #4: SELinux Advanced — Writing Policy and audit2allow
10 min read

RHEL Advanced #4: SELinux Advanced — Writing Policy and audit2allow

Going one level higher than the intermediate post: the structure of .te/.fc/.if policy files, the flow and limits of generating modules with audit2allow, the procedure to compile and install with checkmodule / semodule_package / semodule by hand, plus booleans and interfaces — all in one cycle. The goal is to follow an AVC denial all the way through to a permanent policy module.

RHEL Intermediate #1: Intro to SELinux — Enforcing/Permissive, Labels, Troubleshooting
14 min read

RHEL Intermediate #1: Intro to SELinux — Enforcing/Permissive, Labels, Troubleshooting

A beginner-friendly introduction to SELinux, RHEL's last security layer. Covers the three modes Enforcing/Permissive/Disabled, the shape of labels (context) attached to every file and process, viewing them with ls -Z / ps -Z, fixing labels with chcon/restorecon, making permanent changes via semanage fcontext, toggling booleans, and troubleshooting AVC denials with audit2allow and sealert.