rkt_selinux(8)

📦 version 38.1.87, in centos-stream 9

🎀 NAME 🎀

Hii bestie!! Welcome to rkt_selinux(8), aka the SELinux Policy rkt manual page. This one is all about rkt_selinux — Security Enhanced Linux Policy for the rkt processes. Slay, let’s get into it. 💅✨

💖 DESCRIPTION 💖

Okay so Security-Enhanced Linux secures the rkt processes via flexible mandatory access control. No cap.

The rkt processes execute with the rkt_t SELinux type. Wait, can we check? Yes bestie — run the ps command with the -Z qualifier, like this:

ps -eZ | grep rkt_t

That’s the vibe check for whether those processes are running. 👑

🚪 ENTRYPOINTS 🚪

The rkt_t SELinux type can be entered via the rkt_exec_t file type. Iconic.

The default entrypoint paths for the rkt_t domain are:

/usr/bin/rkt

🧬 PROCESS TYPES 🧬

SELinux defines process types (domains) for each process running on the system. Fr fr.

You can see the context of a process using the -Z option to ps. It’s giving “peek behind the curtain.” 👀

Policy governs the access confined processes have to files. SELinux rkt policy is very flexible, allowing users to setup their rkt processes in as secure a method as possible.

The following process types are defined for rkt:

  • rkt_t
Note: semanage permissive -a rkt_t can be used to make the process type rkt_t permissive. SELinux does not deny access to permissive process types, but the AVC (SELinux denials) messages are still generated. Okay?? Important!! 🚨

🎚️ BOOLEANS 🎚️

SELinux policy is customizable based on least access required. The rkt policy is extremely flexible and has several booleans that allow you to manipulate the policy and run rkt with the tightest access possible. Tightest access = main character energy. 🔥

  • daemons_dontaudit_scheduling — If you want to dontaudit all daemons scheduling requests (setsched, sys_nice), you must turn on the daemons_dontaudit_scheduling boolean. Enabled by default.
setsebool -P daemons_dontaudit_scheduling 1
  • fips_mode — If you want to allow all domains to execute in fips_mode, you must turn on the fips_mode boolean. Enabled by default.
setsebool -P fips_mode 1
  • nscd_use_shm — If you want to allow confined applications to use nscd shared memory, you must turn on the nscd_use_shm boolean. Enabled by default.
setsebool -P nscd_use_shm 1

🔌 PORT TYPES 🔌

SELinux defines port types to represent TCP and UDP ports. Yup.

You can see the types associated with a port by using this command:

semanage port -l

Policy governs the access confined processes have to these ports. SELinux rkt policy is very flexible, allowing users to setup their rkt processes in as secure a method as possible. 💖

The following port types are defined for rkt:

  • rkt_port_t

Default Defined Ports:

tcp 18112

📁 MANAGED FILES 📁

The SELinux process type rkt_t can manage files labeled with the following file types. The paths listed are the default paths for these file types. Note: the process’s UID still needs to have DAC permissions. Don’t forget that part, bestie!! 🫶

  • cluster_conf_t
/etc/cluster(/.*)?
  • cluster_var_lib_t
/var/lib/pcsd(/.*)?
/var/lib/cluster(/.*)?
/var/lib/openais(/.*)?
/var/lib/pengine(/.*)?
/var/lib/corosync(/.*)?
/usr/lib/heartbeat(/.*)?
/var/lib/heartbeat(/.*)?
/var/lib/pacemaker(/.*)?
  • cluster_var_run_t
/var/run/crm(/.*)?
/var/run/cman_.*
/var/run/rsctmp(/.*)?
/var/run/aisexec.*
/var/run/heartbeat(/.*)?
/var/run/pcsd-ruby.socket
/var/run/corosync-qnetd(/.*)?
/var/run/corosync-qdevice(/.*)?
/var/run/pcsd.socket
/var/run/corosync.pid
/var/run/cpglockd.pid
/var/run/rgmanager.pid
/var/run/cluster/rgmanager.sk
  • rkt_var_lib_t
/var/lib/rkt(/.*)?
  • root_t
/sysroot/ostree/deploy/.*-atomic/deploy(/.*)?
/
/initrd

🏷️ FILE CONTEXTS 🏷️

SELinux requires files to have an extended attribute to define the file type. That’s the whole labeling situation. ✨

You can see the context of a file using the -Z option to ls. Cute.

Policy governs the access confined processes have to these files. SELinux rkt policy is very flexible, allowing users to setup their rkt processes in as secure a method as possible.

🌸 STANDARD FILE CONTEXT 🌸

SELinux defines the file context types for the rkt. If you wanted to store files with these types in a different paths, you need to execute the semanage command to specify alternate labeling and then use restorecon to put the labels on disk. Like this:

semanage fcontext -a -t rkt_unit_file_t '/srv/myrkt_content(/.*)?'
restorecon -R -v /srv/myrkt_content
Note: SELinux often uses regular expressions to specify labels that match multiple files. Regex girlies stay winning. 🧚

The following file types are defined for rkt:

  • rkt_exec_t — Set files with the rkt_exec_t type, if you want to transition an executable to the rkt_t domain.
  • rkt_unit_file_t — Set files with the rkt_unit_file_t type, if you want to treat the files as rkt unit content.

Paths:

/usr/lib/systemd/system/rkt-gc.timer, /usr/lib/systemd/system/rkt-gc.service, /usr/lib/systemd/system/rkt-metadata.socket, /usr/lib/systemd/system/rkt-metadata.service
  • rkt_var_lib_t — Set files with the rkt_var_lib_t type, if you want to store the rkt files under the /var/lib directory.
Note: File context can be temporarily modified with the chcon command. If you want to permanently change the file context you need to use the semanage fcontext command. This will modify the SELinux labeling database. You will need to use restorecon to apply the labels. Permanent = use the right tools, bestie!! 💅

🛠️ COMMANDS 🛠️

  • semanage fcontext can also be used to manipulate default file context mappings.
  • semanage permissive can also be used to manipulate whether or not a process type is permissive.
  • semanage module can also be used to enable/disable/install/remove policy modules.
  • semanage port can also be used to manipulate the port definitions.
  • semanage boolean can also be used to manipulate the booleans.
  • system-config-selinux is a GUI tool available to customize SELinux policy settings.

✍️ AUTHOR ✍️

This manual page was auto-generated using sepolicy manpage . So yes, the robots did this one. Still iconic. 🤖💖

👀 SEE ALSO 👀

xoxo bestie 💖 — this page comes from rkt, version/date 26-10-23, and it’s rkt_selinux(8). Catch you in the group chat! 🫶✨

📦 where this page comes from