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_t: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
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.
The SELinux user xguest_u is able to X Windows login.
dns_port_t: 53
pulseaudio_port_t: 4713
flash_port_t: 843,1935
soundd_port_t: 8000,9433,16001
ocsp_port_t: 9080
kerberos_port_t: 88,750,4444
commplex_port_t: 5001
ipp_port_t: 631,8610-8614
transproxy_port_t: 8081
all ports with out defined types
ftp_port_t: 21,990
speech_port_t: 8036
http_cache_port_t: 8080,8118,10001-10010
http_port_t: 80,81,443,488,8008,8009,8443
squid_port_t: 3128,3401,4827
ephemeral_port_t: 32768-61000
dns_port_t: 53
pulseaudio_port_t: 4713
flash_port_t: 843,1935
soundd_port_t: 8000,9433,16001
ocsp_port_t: 9080
kerberos_port_t: 88,750,4444
commplex_port_t: 5001
ipp_port_t: 631,8610-8614
transproxy_port_t: 8081
all ports with out defined types
ftp_port_t: 21,990
speech_port_t: 8036
http_cache_port_t: 8080,8118,10001-10010
http_port_t: 80,81,443,488,8008,8009,8443
squid_port_t: 3128,3401,4827
ephemeral_port_t: 32768-61000
If you want to allow xguest users to configure Network Manager and connect to apache ports, you must turn on the xguest_connect_network boolean.
setsebool -P xguest_connect_network 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 xguest to use blue tooth devices, you must turn on the xguest_use_bluetooth boolean.
setsebool -P xguest_use_bluetooth 1
The SELinux user xguest_u is able execute home content files.
Three things can happen when xguest_t attempts to execute a program.
1. SELinux Policy can deny xguest_t from executing the program.
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
Execute the following t