Security-Enhanced Linux secures the xdm processes via flexible mandatory access control.
If you want to allow the graphical login program to login directly as sysadm_r:sysadm_t, you must turn on the xdm_sysadm_login boolean.
setsebool -P xdm_sysadm_login 1
If you want to allow the graphical login program to execute bootloader, you must turn on the xdm_exec_bootloader boolean.
setsebool -P xdm_exec_bootloader 1
If you want to allow users to resolve user passwd entries directly from ldap rather then using a sssd serve for the xdm_dbusd_t, xdm_t, you must turn on the authlogin_nsswitch_use_ldap boolean.
setsebool -P authlogin_nsswitch_use_ldap 1
If you want to allow confined applications to run with kerberos for the xdm_dbusd_t, xdm_t, you must turn on the kerberos_enabled boolean.
setsebool -P kerberos_enabled 1
You can see the context of a file using the -Z option to lsP Policy governs the access confined processes have to these files. SELinux xdm policy is very flexible allowing users to setup their xdm processes in as secure a method as possible.
The following file types are defined for xdm:
xdm_etc_t
- Set files with the xdm_etc_t type, if you want to store xdm files in the /etc directories.
xdm_exec_t
- Set files with the xdm_exec_t type, if you want to transition an executable to the xdm_t domain.
xdm_home_t
- Set files with the xdm_home_t type, if you want to store xdm files in the users home directory.
xdm_lock_t
- Set files with the xdm_lock_t type, if you want to treat the files as xdm lock data, stored under the /var/lock directory
xdm_log_t
- Set files with the xdm_log_t type, if you want to treat the data as xdm log data, usually stored under the /var/log directory.
xdm_rw_etc_t
- Set files with the xdm_rw_etc_t type, if you want to store xdm rw files in the /etc directories.
xdm_spool_t
- Set files with the xdm_spool_t type, if you want to store the xdm files under the /var/spool directory.
xdm_tmp_t
- Set files with the xdm_tmp_t type, if you want to store xdm temporary files in the /tmp directories.
xdm_tmpfs_t
- Set files with the xdm_tmpfs_t type, if you want to store xdm files on a tmpfs file system.
xdm_unconfined_exec_t
- Set files with the xdm_unconfined_exec_t type, if you want to transition an executable to the xdm_unconfined_t domain.
xdm_var_lib_t
- Set files with the xdm_var_lib_t type, if you want to store the xdm files under the /var/lib directory.
xdm_var_run_t
- Set files with the xdm_var_run_t type, if you want to store the xdm files under the /run directory.
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.
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 xdm policy is very flexible allowing users to setup their xdm processes in as secure a method as possible.
The following port types are defined for xdm:
Default Defined Ports: tcp 177 udp 177
You can see the context of a process using the -Z option to psP Policy governs the access confined processes have to files. SELinux xdm policy is very flexible allowing users to setup their xdm processes in as secure a method as possible.
The following process types are defined for xdm:
xdm_t, xdm_dbusd_t, xdm_unconfined_t
Note: semanage permissive -a PROCESS_TYPE can be used to make a process type permissive. Permissive process types are not denied access by SELinux. AVC messages will still be generated.
The SELinux user type xdm_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.
anon_inodefs_t
auth_cache_t
/var/cache/coolkey(/.*)?
auth_home_t
/root/.google_authenticator
/root/.google_authenticator~
/home/[^/]*/.google_authenticator
/home/[^/]*/.google_authenticator~
cgroup_t
/cgroup
/sys/fs/cgroup
etc_runtime_t
/[^/]+
/etc/mtab.*
/etc/blkid(/.*)?
/etc/nologin.*
/etc/.fstab.hal..+
/halt
/fastboot
/poweroff
/etc/cmtab
/forcefsck
/.autofsck
/.suspended
/fsckoptions
/.autorelabel
/etc/securetty
/etc/nohotplug
/etc/killpower
/etc/ioctl.save
/etc/fstab.REVOKE
/etc/network/ifstate
/etc/sysconfig/hwconf
/etc/ptal/ptal-printd-like
/etc/sysconfig/iptables.save
/etc/xorg.conf.d/00-system-setup-keyboard.conf
/etc/X11/xorg.conf.d/00-system-setup-keyboard.conf
faillog_t
/var/log/btmp.*
/var/run/faillock(/.*)?
/var/log/faillog
/var/log/tallylog
fonts_cache_t
/var/cache/fontconfig(/.*)?
gconf_home_t
/root/.local.*
/root/.gconf(d)?(/.*)?
/home/[^/]*/.local.*
/home/[^/]*/.gconf(d)?(/.*)?
gnome_home_type
initrc_var_run_t
/var/run/utmp
/var/run/random-seed
/var/run/runlevel.dir
/var/run/setmixer_flag
krb5_host_rcache_t
/var/cache/krb5rcache(/.*)?
/var/tmp/nfs_0
/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
lastlog_t
/var/log/lastlog
locale_t
/etc/locale.conf
/usr/lib/locale(/.*)?
/usr/share/locale(/.*)?
/usr/share/zoneinfo(/.*)?
/usr/share/X11/locale(/.*)?
/etc/timezone
/etc/localtime
/etc/sysconfig/clock
/etc/avahi/etc/localtime
/var/empty/sshd/etc/localtime
/var/spool/postfix/etc/localtime