nfsd_selinux(8)

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

✨ nfsd_selinux(8) ✨

okay bestie, welcome to the nfsd_selinux(8) glow-up πŸ’… this is literally the Security Enhanced Linux Policy for the nfsd processes, and we're gonna get you comfy with it. no cap.


🌸 NAME 🌸

nfsd_selinux β€” Security Enhanced Linux Policy for the nfsd processes. it's giving security, it's giving policy, it's giving nfsd. periodt.


πŸŽ€ DESCRIPTION πŸŽ€

Security-Enhanced Linux secures the nfsd processes via flexible mandatory access control. slay.

The nfsd processes execute with the nfsd_t SELinux type. you can check if you have these processes running by executing the ps command with the -Z qualifier. lowkey the easiest vibe check ever.

for example:

ps -eZ | grep nfsd_t

πŸ¦‹ ENTRYPOINTS πŸ¦‹

The nfsd_t SELinux type can be entered via the nfsd_exec_t file type. that's the doorway, bestie.

The default entrypoint paths for the nfsd_t domain are the following:

/usr/bin/rpc.nfsd, /usr/bin/rpc.mountd

πŸ’– PROCESS TYPES πŸ’–

SELinux defines process types (domains) for each process running on the system. yes, every single one gets its own little identity. main character energy fr.

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

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

The following process types are defined for nfsd:

  • nfsd_t
Note: semanage permissive -a nfsd_t can be used to make the process type nfsd_t permissive. SELinux does not deny access to permissive process types, but the AVC (SELinux denials) messages are still generated. so like, it's chill but it's still watching πŸ‘€

🌈 BOOLEANS 🌈

SELinux policy is customizable based on least access required. nfsd policy is extremely flexible and has several booleans that allow you to manipulate the policy and run nfsd with the tightest access possible. bestie, you can tune this thing like a playlist.

  • nfs_export_all_ro β€” If you want to allow any files/directories to be exported read/only via NFS, you must turn on the nfs_export_all_ro boolean. Enabled by default. 🫢
setsebool -P nfs_export_all_ro 1
  • nfs_export_all_rw β€” If you want to allow any files/directories to be exported read/write via NFS, you must turn on the nfs_export_all_rw boolean. Enabled by default. πŸ’œ
setsebool -P nfs_export_all_rw 1
  • daemons_dontaudit_scheduling β€” If you want to dontaudit all daemons scheduling requests (setsched, sys_nice), you must turn on the daemons_dontaudit_scheduling boolean. Enabled by default. πŸ”₯
setsebool -P daemons_dontaudit_scheduling 1
  • fips_mode β€” 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
  • nis_enabled β€” If you want to allow system to run with NIS, you must turn on the nis_enabled boolean. Disabled by default. πŸ™ˆ
setsebool -P nis_enabled 1

πŸ’€ PORT TYPES πŸ’€

SELinux defines port types to represent TCP and UDP ports. the ports have types too, it's giving organized.

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. SELinux nfsd policy is very flexible, allowing users to setup their nfsd processes in as secure a method as possible. same energy, different section.

The following port types are defined for nfsd:

  • nfs_port_t

Default Defined Ports:

tcp 2049,20048-20049
udp 2049,20048-20049

🧚 MANAGED FILES 🧚

The SELinux process type nfsd_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. yeah, SELinux doesn't override DAC, bestie, they're a team.

  • cluster_conf_t β€” paths:
/etc/cluster(/.*)?
  • cluster_var_lib_t β€” paths:
/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 β€” paths:
/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
  • fsadm_var_run_t β€” paths:
/run/fsck(/.*)?
/run/blkid(/.*)?
  • glusterd_log_t β€” paths:
/var/log/glusterfs(/.*)?
  • glusterd_var_run_t β€” paths:
/run/gluster(/.*)?
/run/glusterd.*
/run/glusterd.*
/run/glusterd(/.*)?
  • krb5_host_rcache_t β€” paths:
/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
  • mount_var_run_t β€” paths:
/run/mount(/.*)?
/dev/.mount(/.*)?
/run/davfs2(/.*)?
/var/cache/davfs2(/.*)?
  • nfsd_fs_t β€” paths: (none listed)
  • nfsd_tmp_t β€” paths: (none listed)
  • root_t β€” paths:
/sysroot/.aleph-version.json
/sysroot/ostree/deploy/.*-atomic/deploy(/.*)?
/
/initrd
/var/lib/ntp
  • rpcd_var_run_t β€” paths:
/run/sm-notify.*
/run/rpc.statd(/.*)?
/run/rpc.statd.pid
  • var_lib_nfs_t β€” paths:
/var/lib/nfs(/.*)?
  • var_lib_t β€” paths:
/opt/(.*/)?var/lib(/.*)?
/var/lib(/.*)?
/var/lib/ntp/var/lib(/.*)?

🌟 FILE CONTEXTS 🌟

SELinux requires files to have an extended attribute to define the file type. it's like a little name tag for your files, iconic.

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 nfsd policy is very flexible, allowing users to setup their nfsd processes in as secure a method as possible. we love a secure setup.

πŸŽ€ STANDARD FILE CONTEXT πŸŽ€

SELinux defines the file context types for the nfsd. 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. slay.

semanage fcontext -a -t nfsd_fs_t '/srv/nfsd/content(/.*)?'
restorecon -R -v /srv/mynfsd_content
Note: SELinux often uses regular expressions to specify labels that match multiple files. regex bestie, it's everywhere.

The following file types are defined for nfsd:

  • nfsd_exec_t β€” Set files with the nfsd_exec_t type, if you want to transition an executable to the nfsd_t domain. paths:
/usr/bin/rpc.nfsd, /usr/bin/rpc.mountd
  • nfsd_fs_t β€” Set files with the nfsd_fs_t type, if you want to treat the files as nfsd fs data.
  • nfsd_initrc_exec_t β€” Set files with the nfsd_initrc_exec_t type, if you want to transition an executable to the nfsd_initrc_t domain.
  • nfsd_tmp_t β€” Set files with the nfsd_tmp_t type, if you want to store nfsd temporary files in the /tmp directories.
  • nfsd_unit_file_t β€” Set files with the nfsd_unit_file_t type, if you want to treat the files as nfsd unit content.
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. so like, temporary vs permanent, know the difference bestie πŸ’…

🌸 SHARING FILES 🌸

If you want to share files with multiple domains (Apache, FTP, rsync, Samba), you can set a file context of public_content_t and public_content_rw_t. These context allow any of the above domains to read the content. If you want a particular domain to write to the public_content_rw_t domain, you must set the appropriate boolean. sharing is caring, but securely.

Allow nfsd servers to read the /var/nfsd directory by adding the public_content_t file type to the directory and by restoring the file type.

semanage fcontext -a -t public_content_t "/var/nfsd(/.*)?"
restorecon -F -R -v /var/nfsd

Allow nfsd servers to read and write /var/nfsd/incoming by adding the public_content_rw_t type to the directory and by restoring the file type. You also need to turn on the nfsd_anon_write boolean.

semanage fcontext -a -t public_content_rw_t "/var/nfsd/incoming(/.*)?"
restorecon -F -R -v /var/nfsd/incoming
setsebool -P nfsd_anon_write 1

If you want to allow nfs servers to modify public files used for public file transfer services. Files/Directories must be labeled public_content_rw_t. you must turn on the nfsd_anon_write boolean.

setsebool -P nfsd_anon_write 1

πŸ’œ COMMANDS πŸ’œ

Β­semanage fcontext can also be used to manipulate default file context mappings.

Β­semanage permissive can also be used to manipulate whether or not a process type is permissive.

Β­semanage module can also be used to enable/disable/install/remove policy modules.

Β­semanage port can also be used to manipulate the port definitions.

Β­semanage boolean can also be used to manipulate the booleans.

system-config-selinux is a GUI tool available to customize SELinux policy settings. GUI girlies rise up 🫢


🌈 AUTHOR 🌈

This manual page was auto-generated using sepolicy manpage .


⭐ SEE ALSO ⭐

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


okay that's the whole page, bestie πŸ’– you're officially an nfsd_selinux expert. this page brought to you by nfsd, version 26-10-06 β€” go slay some SELinux policy βœ¨πŸ‘‘

πŸ“¦ where this page comes from