xguest_selinux(8) xguest SELinux Policy documentation xguest_selinux(8)NAME
xguest_u - Least privledge xwindows user role - Security Enhanced Linux
Policy
DESCRIPTION
xguest_u is an SELinux User defined in the SELinux policy. SELinux
users have default roles, xguest_r. The default role has a default
type, xguest_t, associated with it.
The SELinux user will usually login to a system with a context that
looks like:
xguest_u:xguest_r:xguest_u:s0-s0:c0.c1023
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 xguest_u
user, you would execute:
semanage login -m -s xguest_u __default__
If you want to map the one Linux user (joe) to the SELinux user xguest,
you would execute:
$ semanage login -a -s xguest_u joe
USER DESCRIPTION
The SELinux user xguest_u is defined in policy as a unprivileged user.
SELinux prevents unprivileged users from doing administration tasks
without transitioning to a different role.
SUDO
The SELinux type xguest_t is not allowed to execute sudo.
X WINDOWS LOGIN
The SELinux user xguest_u is able to X Windows login.
TERMINAL LOGIN
The SELinux user xguest_u is able to terminal login.
NETWORK
The SELinux user xguest_u is able to connect to the following tcp
ports.
dns_port_t: 53
ipp_port_t: 631,8610-8614
transproxy_port_t: 8081
ocsp_port_t: 9080
kerberos_port_t: 88,750,4444
all ports with out defined types
ftp_port_t: 21,990
speech_port_t: 8036
squid_port_t: 3128,3401,4827
http_cache_port_t: 8080,8118,8123,10001-10010
http_port_t: 80,443,488,8008,8009,8443
flash_port_t: 843,1935
pulseaudio_port_t: 4713
soundd_port_t: 8000,9433,16001
BOOLEANS
SELinux policy is customizable based on least access required.
xguest_t policy is extremely flexible and has several booleans that
allow you to manipulate the policy and run xguest_t with the tightest
access possible.
If you want to allow xguest users to configure Network Manager and con‐
nect to apache ports, you must turn on the xguest_connect_network bool‐
ean.
setsebool -P xguest_connect_network 1
If you want to allow users to connect to the local mysql server, you
must turn on the allow_user_mysql_connect boolean.
setsebool -P allow_user_mysql_connect 1
If you want to control users use of ping and traceroute, you must turn
on the user_ping boolean.
setsebool -P user_ping 1
If you want to allow w to display everyone, you must turn on the
user_ttyfile_stat boolean.
setsebool -P user_ttyfile_stat 1
If you want to allow user music sharing, you must turn on the
user_share_music boolean.
setsebool -P user_share_music 1
If you want to allow regular users direct dri device access, you must
turn on the user_direct_dri boolean.
setsebool -P user_direct_dri 1
If you want to allow xguest users to use blue tooth devices, you must
turn on the xguest_use_bluetooth boolean.
setsebool -P xguest_use_bluetooth 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
user_rw_noexattrfile boolean.
setsebool -P user_rw_noexattrfile 1
If you want to allow users to run TCP servers (bind to ports and accept
connection from the same domain and outside users) disabling this
forces FTP passive mode and may change other protocols, you must turn
on the user_tcp_server boolean.
setsebool -P user_tcp_server 1
If you want to allow regular users direct mouse access, you must turn
on the user_direct_mouse boolean.
setsebool -P user_direct_mouse 1
If you want to allow user processes to change their priority, you must
turn on the user_setrlimit boolean.
setsebool -P user_setrlimit 1
If you want to allow users to connect to PostgreSQL, you must turn on
the allow_user_postgresql_connect boolean.
setsebool -P allow_user_postgresql_connect 1
If you want to allow xguest users to mount removable media, you must
turn on the xguest_mount_media boolean.
setsebool -P xguest_mount_media 1
If you want to allow users to read system messages, you must turn on
the user_dmesg boolean.
setsebool -P user_dmesg 1
HOME_EXEC
The SELinux user xguest_u is able execute home content files.
TRANSITIONS
Three things can happen when xguest_t attempts to execute a program.
1. SELinux Policy can deny xguest_t from executing the program.
2. SELinux Policy can allow xguest_t to execute the program in the cur‐
rent user type.
Execute the following to see the types that the SELinux user
xguest_t can execute without transitioning:
sesearch -A -s xguest_t -c file -p execute_no_trans
3. SELinux can allow xguest_t to execute the program and transition to
a new type.
Execute the following to see the types that the SELinux user
xguest_t can execute and transition:
$ sesearch -A -s xguest_t -c process -p transition
COMMANDS
semanage login can also be used to manipulate the Linux User to SELinux
User mappings
semanage user can also be used to manipulate SELinux user definitions.
system-config-selinux is a GUI tool available to customize SELinux pol‐
icy settings.
AUTHOR
This manual page was autogenerated by genuserman.py.
SEE ALSOselinux(8), semanage(8).
mgrepl@redhat.com xguest xguest_selinux(8)
