This corresponds to the standard policy language of SELinux [1], used for example, by the SELinux Reference Policy [2] or the Android policies [3][4].
Extensions and files to highlight:
* SELinux Type Enforcement (*.te)
* SELinux Interface File (*.if)
* M4 Macros of Reference Policy (*.spt)
* Some policy build files and policy config. files (access_vectors, mls, mcs, mls_macros, te_macros, policy_capabilities, seapp_contexts, port_contexts), and monolithic policy (policy.conf). NOTE: I added only relevant configuration files and policy building, since many have very generic names.
Also, this file contains common rules and keywords between `selinux-fc.xml` and `selinux-cil.xml`. For example, it contains the RegExp highlighting and the Permissions keywords. The idea is to avoid having repeated keywords and rules between the SELinux highlighting files.
**References:**
[1] SELinux Wiki. PolicyLanguage: https://selinuxproject.org/page/PolicyLanguage#Kernel_Policy_Language
[2] SELinux Reference Policy: https://github.com/SELinuxProject/refpolicy/wiki
[3] Security-Enhanced Linux in Android: https://source.android.com/security/selinux/
[4] SELinux policy configuration for AOSP: https://android.googlesource.com/platform/system/sepolicy/