user_u is an SELinux User defined in the SELinux policy. SELinux users have default roles, user_r. The default role has a default type, user_t, associated with it.
The SELinux user will usually login to a system with a context that looks like:
user_u:user_r:user_t:s0
Linux users are automatically assigned an SELinux users at login. Login programs use the SELinux User to assign initial context to the user's shell.
SELinux policy uses the context to control the user's access.
By default all users are assigned to the SELinux user via the __default__ flag
On Targeted policy systems the __default__ user is assigned to the unconfined_u SELinux user.
You can list all Linux User to SELinux user mapping using:
semanage login -l
If you wanted to change the default user mapping to use the user_u user, you would execute:
semanage login -m -s user_u __default__
If you want to map the one Linux user (joe) to the SELinux user user, you would execute:
$ semanage login -a -s user_u joe
The SELinux user user_u is defined in policy as a unprivileged user. SELinux prevents unprivileged users from doing administration tasks without transitioning to a different role.
The SELinux user user_u is able to X Windows login.
6000-6020
all ports > 1024
32768-60999
3689
all ports with out defined types
all ports
8955
53,853
5432,9898
389,636,3268,3269,7389
32768-60999
all ports with out defined types
9080
111
all ports < 1024
88,750,4444
all ports with out defined types
32768-60999
all ports > 1024
all ports
8955
53,853
5432,9898
389,636,3268,3269,7389
32768-60999
all ports with out defined types
9080
111
all ports < 1024
88,750,4444
If you want to allow users to resolve user passwd entries directly from ldap rather then using a sssd server, you must turn on the authlogin_nsswitch_use_ldap boolean. Disabled by default.
setsebool -P authlogin_nsswitch_use_ldap 1
If you want to determine whether crond can execute jobs in the user domain as opposed to the the generic cronjob domain, you must turn on the cron_userdomain_transition boolean. Enabled by default.
setsebool -P cron_userdomain_transition 1
If you want to deny all system processes and Linux users to use bluetooth wireless technology, you must turn on the deny_bluetooth boolean. Disabled by default.
setsebool -P deny_bluetooth 1
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 deny any process from ptracing or debugging any other processes, you must turn on the deny_ptrace boolean. Disabled by default.
setsebool -P deny_ptrace 1
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
If you want to determine whether calling user domains can execute Git daemon in the git_session_t domain, you must turn on the git_session_users boolean. Disabled by default.
setsebool -P git_session_users 1
If you want to allow httpd cgi support, you must turn on the httpd_enable_cgi boolean. Enabled by default.
setsebool -P httpd_enable_cgi 1
If you want to allow confined applications to run with kerberos, you must turn on the kerberos_enabled boolean. Enabled by default.
setsebool -P kerberos_enabled 1
If you want to allow system to run with NIS, you must turn on the nis_enabled boolean. Disabled by default.
setsebool -P nis_enabled 1
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
If you want to determine whether calling user domains can execute Polipo daemon in the polipo_session_t domain, you must turn on the polipo_session_users boolean. Disabled by default.
setsebool -P polipo_session_users 1
If you want to allow pppd to be run for a regular user, you must turn on the pppd_for_user boolean. Disabled by default.
setsebool -P pppd_for_user 1
If you want to allow all unconfined executables to use libraries requiring text relocation that are not labeled textrel_shlib_t, you must turn on the selinuxuser_execmod boolean. Enabled by default.
setsebool -P selinuxuser_execmod 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. Enabled by default.
setsebool -P selinuxuser_execstack 1
If you want to allow users to connect to the local mysql server, you must turn on the selinuxuser_mysql_connect_enabled boolean. Disabled by default.
setsebool -P selinuxuser_mysql_connect_enabled 1
If you want to allow confined users the ability to execute the ping and traceroute commands, you must turn on the selinuxuser_ping boolean. Enabled by default.
setsebool -P selinuxuser_ping 1
If you want to allow users to connect to PostgreSQL, you must turn on the selinuxuser_postgresql_connect_enabled boolean. Disabled by default.
setsebool -P selinuxuser_postgresql_connect_enabled 1
If you want to allow user to r/w files on filesystems that do not have extended attributes (FAT, CDROM, FLOPPY), you must turn on the selinuxuser_rw_noexattrfile boolean. Enabled by default.
setsebool -P selinuxuser_rw_noexattrfile 1
If you want to allow user to use ssh chroot environment, you must turn on the selinuxuser_use_ssh_chroot boolean. Disabled by default.
setsebool -P selinuxuser_use_ssh_chroot 1
If you want to allow unprivileged user to create and transition to svirt domains, you must turn on the unprivuser_use_svirt boolean. Disabled by default.
setsebool -P unprivuser_use_svirt 1
If you want to support NFS home directories, you must turn on the use_nfs_home_dirs boolean. Disabled by default.
setsebool -P use_nfs_home_dirs 1
If you want to support SAMBA home directories, you must turn on the use_samba_home_dirs boolean. Disabled by default.
setsebool -P use_samba_home_dirs 1
The SELinux user user_u is able execute home content files.
Three things can happen when user_t attempts to execute a program.
1. SELinux Policy can deny user_t from executing the program.
Execute the following to see the types that the SELinux user user_t can execute without transitioning:
sesearch -A -s user_t -c file -p execute_no_trans
Execute the following to see the types that the SELinux user user_t can execute and transition:
$ sesearch -A -s user_t -c process -p transition
The SELinux process type user_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.
alsa_home_t
/home/[^/]+/.asoundrc
anon_inodefs_t
auth_cache_t
/var/cache/coolkey(/.*)?
bluetooth_helper_tmp_t
bluetooth_helper_tmpfs_t
cgroup_t
/sys/fs/cgroup
chrome_sandbox_tmpfs_t
cifs_t
dosfs_t
games_data_t
/var/games(/.*)?
/var/lib/games(/.*)?
gconf_tmp_t
/tmp/gconfd-[^/]+/.*
git_user_content_t
/home/[^/]+/public_git(/.*)?
gkeyringd_tmp_t
/var/run/user/[^/]*/keyring.*
gnome_home_type
gpg_agent_tmp_t
/home/[^/]+/.gnupg/log-socket
httpd_user_content_t
/home/[^/]+/((www)|(web)|(public_html))(/.+)?
httpd_user_htaccess_t
/home/[^/]+/((www)|(web)|(public_html))(/.*)?/.htaccess
httpd_user_ra_content_t
/home/[^/]+/((www)|(web)|(public_html))(/.*)?/logs(/.*)?
httpd_user_rw_content_t
httpd_user_script_exec_t
/home/[^/]+/((www)|(web)|(public_html))/cgi-bin(/.+)?
irc_home_t
/home/[^/]+/.irssi(/.*)?
/home/[^/]+/irclog(/.*)?
/home/[^/]+/.ircmotd
irc_tmp_t
irssi_home_t
mail_spool_t
/var/mail(/.*)?
/var/spool/imap(/.*)?
/var/spool/mail(/.*)?
/var/spool/smtpd(/.*)?
mpd_user_data_t
mqueue_spool_t
/var/spool/(client)?mqueue(/.*)?
/var/spool/mqueue.in(/.*)?
nfs_t
noxattrfs
all files on file systems which do not support extended attributes
pulseaudio_tmpfs_t
pulseaudio_tmpfsfile
sandbox_file_t
sandbox_tmpfs_type
all sandbox content in tmpfs file systems
screen_home_t
/root/.screen(/.*)?
/home/[^/]+/.screen(/.*)?
/home/[^/]+/.screenrc
/home/[^/]+/.tmux.conf
security_t
/selinux
ssh_home_t
/var/lib/[^/]+/.ssh(/.*)?
/root/.ssh(/.*)?
/var/lib/one/.ssh(/.*)?
/var/lib/pgsql/.ssh(/.*)?
/var/lib/openshift/[^/]+/.ssh(/.*)?
/var/lib/amanda/.ssh(/.*)?
/var/lib/stickshift/[^/]+/.ssh(/.*)?
/var/lib/gitolite/.ssh(/.*)?
/var/lib/nocpulse/.ssh(/.*)?
/var/lib/gitolite3/.ssh(/.*)?
/var/lib/openshift/gear/[^/]+/.ssh(/.*)?
/root/.shosts
/home/[^/]+/.ssh(/.*)?
/home/[^/]+/.ansible/cp/.*
/home/[^/]+/.shosts
systemd_passwd_var_run_t
/var/run/systemd/ask-password(/.*)?
/var/run/systemd/ask-password-block(/.*)?
usbfs_t
user_fonts_cache_t
/root/.fontconfig(/.*)?
/root/.fonts/auto(/.*)?
/root/.fonts.cache-.*
/home/[^/]+/.fontconfig(/.*)?
/home/[^/]+/.fonts/auto(/.*)?
/home/[^/]+/.fonts.cache-.*
user_home_type
all user home files
user_tmp_t
/dev/shm/mono.*
/var/run/user(/.*)?
/tmp/.ICE-unix(/.*)?
/tmp/.X11-unix(/.*)?
/dev/shm/pulse-shm.*
/tmp/.X0-lock
/tmp/hsperfdata_root
/var/tmp/hsperfdata_root
/home/[^/]+/tmp
/home/[^/]+/.tmp
/tmp/gconfd-[^/]+
user_tmp_type
all user tmp files
virt_image_type
all virtual image files
xserver_tmpfs_t
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.