livecd_selinux(8)

πŸ“¦
version 20250627+git412.dbf877ab7 Β· 7 versions
, in opensuse-leap 16.0

πŸ’… livecd_selinux β€” the SELinux glow-up for livecd processes ✨

okay bestie, so this is the livecd_selinux page from the SELinux Policy livecd manual β€” yes the manual name is literally livecd_selinux(8) and we're folding that in right here at the top so you never lose track πŸŽ€


🌸 NAME 🌸

livecd_selinux β€” Security Enhanced Linux Policy for the livecd processes. that's it, that's the whole vibe. πŸ‘‘


✨ DESCRIPTION ✨

Security-Enhanced Linux secures the livecd processes via flexible mandatory access control. like, MAC but make it fashion πŸ’…

The livecd processes execute with the livecd_t SELinux type. wanna check if you've got these processes running? just run the ps command with the -Z qualifier. iykyk.

For example:

ps -eZ | grep livecd_t

πŸ¦‹ ENTRYPOINTS πŸ¦‹

so the livecd_t SELinux type can be entered via the livecd_exec_t file type. that's the door πŸšͺ✨

The default entrypoint paths for the livecd_t domain are literally these:

/usr/bin/livecd-creator

πŸŽ€ PROCESS TYPES πŸŽ€

SELinux defines process types (domains) for each process running on the system. yes, every single one gets its own little domain, main character energy for everybody πŸ’–

You can see the context of a process using the -Z option to ps.

Policy governs the access confined processes have to files. SELinux livecd policy is very flexible allowing users to setup their livecd processes in as secure a method as possible. flexible and secure, we love a multitasker 🫢

The following process types are defined for livecd:

livecd_t
Note: semanage permissive -a livecd_t can be used to make the process type livecd_t permissive. SELinux does not deny access to permissive process types, but the AVC (SELinux denials) messages are still generated. so like, it stops blocking but it's still gonna talk about you in the group chat πŸ’€

πŸ”₯ BOOLEANS πŸ”₯

SELinux policy is customizable based on least access required. livecd policy is extremely flexible and has several booleans that allow you to manipulate the policy and run livecd with the tightest access possible. tightest access possible, like a perfectly tailored fit πŸ‘—βœ¨

If you want to deny user domains applications to map a memory region as both executable and writable, this is dangerous and the executable should be reported in bugzilla, you must turn on the deny_execmem boolean. Disabled by default.

setsebool -P deny_execmem 1

If you want to control the ability to mmap a low area of the address space, as configured by /proc/sys/vm/mmap_min_addr, you must turn on the mmap_low_allowed boolean. Disabled by default.

setsebool -P mmap_low_allowed 1

If you want to disable kernel module loading, you must turn on the secure_mode_insmod boolean. Disabled by default.

setsebool -P secure_mode_insmod 1

If you want to allow unconfined executables to make their heap memory executable. Doing this is a really bad idea. Probably indicates a badly coded executable, but could indicate an attack. This executable should be reported in bugzilla, you must turn on the selinuxuser_execheap boolean. Disabled by default.

setsebool -P selinuxuser_execheap 1

If you want to allow unconfined executables to make their stack executable. This should never, ever be necessary. Probably indicates a badly coded executable, but could indicate an attack. This executable should be reported in bugzilla, you must turn on the selinuxuser_execstack boolean. Disabled by default.

setsebool -P selinuxuser_execstack 1

🌈 MANAGED FILES 🌈

The SELinux process type livecd_t can manage files labeled with the following file types. The paths listed are the default paths for these file types. Note the processes UID still need to have DAC permissions β€” SELinux isn't out here overriding DAC, bestie, they're a team 🀝

file_type

  • all files on the system

that's it. all of them. the whole system. slay, honestly πŸ‘‘


🧚 FILE CONTEXTS 🧚

SELinux requires files to have an extended attribute to define the file type.

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

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

⭐ STANDARD FILE CONTEXT ⭐

SELinux defines the file context types for the livecd, 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. relabeling era ✨

semanage fcontext -a -t livecd_exec_t '/srv/livecd/content(/.*)?'
restorecon -R -v /srv/mylivecd_content
Note: SELinux often uses regular expressions to specify labels that match multiple files. regex girlies rise πŸŽ€

The following file types are defined for livecd:

livecd_exec_t

  • Set files with the livecd_exec_t type, if you want to transition an executable to the livecd_t domain.

livecd_tmp_t

  • Set files with the livecd_tmp_t type, if you want to store livecd temporary files in the /tmp directories.
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. temporary vs permanent, know the difference bestie πŸ’…

πŸ’œ COMMANDS πŸ’œ

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 boolean can also be used to manipulate the booleans

system-config-selinux is a GUI tool available to customize SELinux policy settings. a whole GUI, for the girlies who like buttons πŸ–±οΈπŸ’–


πŸ“ AUTHOR πŸ“

This manual page was auto-generated using sepolicy manpage . (yes, the robots wrote it, we just gave it ✨flair✨)


πŸ” SEE ALSO πŸ”

selinux(8), livecd(8), semanage(8), restorecon(8), chcon(1), sepolicy(8), setsebool(8)


and that's the whole page, bestie 🫢 this came from the livecd manual, dated 26-10-06, and it's living in livecd_selinux(8) β€” go forth and label responsibly πŸ’…πŸ’–

πŸ“¦ where this page comes from