nmbd_selinux(8)

📦
version 20250627+git412.dbf877ab7 · 7 versions
, in opensuse-leap 16.0

🌸 NAME 🌸

okay bestie, welcome to the nmbd_selinux(8) page! 💖 This is all about nmbd_selinux — Security Enhanced Linux Policy for the nmbd processes. Periodt.

✨ DESCRIPTION ✨

Security-Enhanced Linux secures the nmbd processes with flexible mandatory access control. It’s giving very strict, very fair bouncer energy for your processes. 💅

The nmbd processes run with the nmbd_t SELinux type. Wanna check if you’ve got these processes running? Run the ps command with the -Z qualifier, like this:

ps -eZ | grep nmbd_t

🚪 ENTRYPOINTS 🚪

The nmbd_t SELinux type can be entered via the nmbd_exec_t file type. The default entrypoint paths for the nmbd_t domain are:

  • /usr/bin/nmbd

👑 PROCESS TYPES 👑

SELinux defines process types (domains) for each process running on the system. You can see the context of a process using the -Z option to ps. 👀

Policy governs the access confined processes have to files. The SELinux nmbd policy is very flexible, allowing users to set up their nmbd processes in as secure a method as possible. ✨

The following process types are defined for nmbd:

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

🎚️ BOOLEANS 🎚️

SELinux policy is customizable based on least access required. The nmbd policy is extremely flexible and has several booleans that allow you to manipulate the policy and run nmbd with the tightest access possible. 🫶

  • daemons_dontaudit_scheduling — if you want to dontaudit all daemons scheduling requests (setsched, sys_nice), you must turn on this boolean. Enabled by default. Flip it with setsebool -P daemons_dontaudit_scheduling 1.
  • fips_mode — if you want to allow all domains to execute in fips_mode, you must turn on this boolean. Enabled by default. Flip it with setsebool -P fips_mode 1.
  • nis_enabled — if you want to allow system to run with NIS, you must turn on this boolean. Disabled by default. Flip it with setsebool -P nis_enabled 1.
  • samba_export_all_ro — if you want to allow samba to share any file/directory read only, you must turn on this boolean. Disabled by default. Flip it with setsebool -P samba_export_all_ro 1.
  • samba_export_all_rw — if you want to allow samba to share any file/directory read/write, you must turn on this boolean. Disabled by default. Flip it with setsebool -P samba_export_all_rw 1.

🔌 PORT TYPES 🔌

SELinux defines port types to represent TCP and UDP ports. You can see the types associated with a port by using the following command:

semanage port -l

Policy governs the access confined processes have to these ports. The SELinux nmbd policy is very flexible, allowing users to set up their nmbd processes in as secure a method as possible. 💅

The following port types are defined for nmbd:

  • nmbd_port_t
    • Default Defined Ports: udp 137,138

📂 MANAGED FILES 📂

The SELinux process type nmbd_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. 🫡

  • 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
    • /run/crm(/.*)?
    • /run/cman_.*
    • /run/rsctmp(/.*)?
    • /run/aisexec.*
    • /run/heartbeat(/.*)?
    • /run/pcsd-ruby.socket
    • /run/corosync-qnetd(/.*)?
    • /run/corosync-qdevice(/.*)?
    • /run/pcsd.socket
    • /run/corosync.pid
    • /run/cpglockd.pid
    • /run/rgmanager.pid
    • /run/cluster/rgmanager.sk
  • ctdbd_var_lib_t
    • /var/lib/ctdb(/.*)?
    • /var/lib/ctdbd(/.*)?
  • krb5_host_rcache_t
    • /var/tmp/krb5_0.rcache2
    • /var/cache/krb5rcache(/.*)?
    • /var/tmp/nfs_0
    • /var/tmp/DNS_25
    • /var/tmp/host_0
    • /var/tmp/imap_0
    • /var/tmp/HTTP_23
    • /var/tmp/HTTP_48
    • /var/tmp/ldap_55
    • /var/tmp/ldap_487
    • /var/tmp/ldapmap1_0
  • nmbd_var_run_t
    • /run/nmbd(/.*)?
    • /run/samba/nmbd(/.*)?
    • /run/samba/nmbd.pid
    • /run/samba/messages.tdb
    • /run/samba/namelist.debug
    • /run/samba/unexpected.tdb
  • non_security_file_type
  • noxattrfs
    • all files on file systems which do not support extended attributes
  • root_t
    • /sysroot/.aleph-version.json
    • /sysroot/ostree/deploy/.*-atomic/deploy(/.*)?
    • /
    • /initrd
    • /var/lib/ntp
  • samba_log_t
    • /var/log/samba(/.*)?

🏷️ 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. The SELinux nmbd policy is very flexible, allowing users to set up their nmbd processes in as secure a method as possible. ✨

🎀 STANDARD FILE CONTEXT 🎀

SELinux defines the file context types for the nmbd. 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. 🌈

semanage fcontext -a -t nmbd_exec_t '/srv/nmbd/content(/.*)?'
restorecon -R -v /srv/mynmbd_content
Note: SELinux often uses regular expressions to specify labels that match multiple files. 🧚

The following file types are defined for nmbd:

  • nmbd_exec_t
    • Set files with the nmbd_exec_t type, if you want to transition an executable to the nmbd_t domain.
  • nmbd_var_run_t
    • Set files with the nmbd_var_run_t type, if you want to store the nmbd files under the /run or /var/run directory.
    • Paths: /run/nmbd(/.*)?, /run/samba/nmbd(/.*)?, /run/samba/nmbd.pid, /run/samba/messages.tdb, /run/samba/namelist.debug, /run/samba/unexpected.tdb
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. 😌

🛠️ 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. 🤖

👀 SEE ALSO 👀

okay that’s the whole glow-up, bestie! This was the nmbd_selinux(8) manual page, with source/version nmbd and date 26-10-06. Slay responsibly. 💅✨

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