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<h1 align="center">xserver_selinux</h1>
<a href="#NAME">NAME</a><br>
<a href="#DESCRIPTION">DESCRIPTION</a><br>
<a href="#ENTRYPOINTS">ENTRYPOINTS</a><br>
<a href="#PROCESS TYPES">PROCESS TYPES</a><br>
<a href="#BOOLEANS">BOOLEANS</a><br>
<a href="#PORT TYPES">PORT TYPES</a><br>
<a href="#MANAGED FILES">MANAGED FILES</a><br>
<a href="#FILE CONTEXTS">FILE CONTEXTS</a><br>
<a href="#COMMANDS">COMMANDS</a><br>
<a href="#AUTHOR">AUTHOR</a><br>
<a href="#SEE ALSO">SEE ALSO</a><br>
<hr>
<h2>NAME
<a name="NAME"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">xserver_selinux
− Security Enhanced Linux Policy for the xserver
processes</p>
<h2>DESCRIPTION
<a name="DESCRIPTION"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">Security-Enhanced
Linux secures the xserver processes via flexible mandatory
access control.</p>
<p style="margin-left:11%; margin-top: 1em">The xserver
processes execute with the xserver_t SELinux type. You can
check if you have these processes running by executing the
<b>ps</b> command with the <b>−Z</b> qualifier.</p>
<p style="margin-left:11%; margin-top: 1em">For
example:</p>
<p style="margin-left:11%; margin-top: 1em"><b>ps -eZ |
grep xserver_t</b></p>
<h2>ENTRYPOINTS
<a name="ENTRYPOINTS"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">The xserver_t
SELinux type can be entered via the <b>xserver_exec_t</b>
file type.</p>
<p style="margin-left:11%; margin-top: 1em">The default
entrypoint paths for the xserver_t domain are the
following:</p>
<p style="margin-left:11%; margin-top: 1em">/usr/bin/nvidia.*,
/usr/bin/Xair, /usr/bin/Xorg, /usr/bin/Xvnc,
/usr/bin/Xephyr, /usr/bin/x11vnc, /usr/X11R6/bin/X,
/usr/bin/Xwayland, /usr/X11R6/bin/Xorg,
/usr/X11R6/bin/Xipaq, /usr/libexec/Xorg.bin,
/usr/X11R6/bin/XFree86, /usr/libexec/Xorg.wrap,
/usr/X11R6/bin/Xwrapper,
/usr/libexec/gsd-backlight-helper</p>
<h2>PROCESS TYPES
<a name="PROCESS TYPES"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">SELinux defines
process types (domains) for each process running on the
system</p>
<p style="margin-left:11%; margin-top: 1em">You can see the
context of a process using the <b>−Z</b> option to
<b>ps</b></p>
<p style="margin-left:11%; margin-top: 1em">Policy governs
the access confined processes have to files. SELinux xserver
policy is very flexible allowing users to setup their
xserver processes in as secure a method as possible.</p>
<p style="margin-left:11%; margin-top: 1em">The following
process types are defined for xserver:</p>
<p style="margin-left:11%; margin-top: 1em"><b>xserver_t</b></p>
<p style="margin-left:11%; margin-top: 1em">Note:
<b>semanage permissive -a xserver_t</b> can be used to make
the process type xserver_t permissive. SELinux does not deny
access to permissive process types, but the AVC (SELinux
denials) messages are still generated.</p>
<h2>BOOLEANS
<a name="BOOLEANS"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">SELinux policy
is customizable based on least access required. xserver
policy is extremely flexible and has several booleans that
allow you to manipulate the policy and run xserver with the
tightest access possible.</p>
<p style="margin-left:11%; margin-top: 1em">If you want to
allows XServer to execute writable memory, you must turn on
the xserver_execmem boolean. Disabled by default.</p>
<p style="margin-left:11%; margin-top: 1em"><b>setsebool -P
xserver_execmem 1</b></p>
<p style="margin-left:11%; margin-top: 1em">If you want to
support X userspace object manager, you must turn on the
xserver_object_manager boolean. Disabled by default.</p>
<p style="margin-left:11%; margin-top: 1em"><b>setsebool -P
xserver_object_manager 1</b></p>
<p style="margin-left:11%; margin-top: 1em">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.</p>
<p style="margin-left:11%; margin-top: 1em"><b>setsebool -P
deny_execmem 1</b></p>
<p style="margin-left:11%; margin-top: 1em">If you want to
control the ability to mmap a low area of the address space,
as configured by /proc/sys/vm/mmap_min_addr, you must turn
on the mmap_low_allowed boolean. Disabled by default.</p>
<p style="margin-left:11%; margin-top: 1em"><b>setsebool -P
mmap_low_allowed 1</b></p>
<p style="margin-left:11%; margin-top: 1em">If you want to
allow system to run with NIS, you must turn on the
nis_enabled boolean. Disabled by default.</p>
<p style="margin-left:11%; margin-top: 1em"><b>setsebool -P
nis_enabled 1</b></p>
<p style="margin-left:11%; margin-top: 1em">If you want to
disable kernel module loading, you must turn on the
secure_mode_insmod boolean. Disabled by default.</p>
<p style="margin-left:11%; margin-top: 1em"><b>setsebool -P
secure_mode_insmod 1</b></p>
<p style="margin-left:11%; margin-top: 1em">If you want to
allow unconfined executables to make their heap memory
executable. Doing this is a really bad idea. Probably
indicates a badly coded executable, but could indicate an
attack. This executable should be reported in bugzilla, you
must turn on the selinuxuser_execheap boolean. Disabled by
default.</p>
<p style="margin-left:11%; margin-top: 1em"><b>setsebool -P
selinuxuser_execheap 1</b></p>
<p style="margin-left:11%; margin-top: 1em">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.</p>
<p style="margin-left:11%; margin-top: 1em"><b>setsebool -P
selinuxuser_execstack 1</b></p>
<h2>PORT TYPES
<a name="PORT TYPES"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">SELinux defines
port types to represent TCP and UDP ports.</p>
<p style="margin-left:11%; margin-top: 1em">You can see the
types associated with a port by using the following
command:</p>
<p style="margin-left:11%; margin-top: 1em"><b>semanage
port -l</b></p>
<p style="margin-left:11%; margin-top: 1em">Policy governs
the access confined processes have to these ports. SELinux
xserver policy is very flexible allowing users to setup
their xserver processes in as secure a method as
possible.</p>
<p style="margin-left:11%; margin-top: 1em">The following
port types are defined for xserver: <b><br>
xserver_port_t</b></p>
<p style="margin-left:11%; margin-top: 1em">Default Defined
Ports:</p>
<p style="margin-left:26%;">tcp 6000-6020</p>
<h2>MANAGED FILES
<a name="MANAGED FILES"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">The SELinux
process type xserver_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.</p>
<p style="margin-left:11%; margin-top: 1em"><b>file_type</b></p>
<p style="margin-left:11%; margin-top: 1em">all files on
the system</p>
<h2>FILE CONTEXTS
<a name="FILE CONTEXTS"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">SELinux
requires files to have an extended attribute to define the
file type.</p>
<p style="margin-left:11%; margin-top: 1em">You can see the
context of a file using the <b>−Z</b> option to
<b>ls</b></p>
<p style="margin-left:11%; margin-top: 1em">Policy governs
the access confined processes have to these files. SELinux
xserver policy is very flexible allowing users to setup
their xserver processes in as secure a method as
possible.</p>
<p style="margin-left:11%; margin-top: 1em"><b>STANDARD
FILE CONTEXT</b></p>
<p style="margin-left:11%; margin-top: 1em">SELinux defines
the file context types for the xserver, 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.</p>
<p style="margin-left:11%; margin-top: 1em"><b>semanage
fcontext -a -t xserver_log_t
’/srv/myxserver_content(/.*)?’ <br>
restorecon -R -v /srv/myxserver_content</b></p>
<p style="margin-left:11%; margin-top: 1em">Note: SELinux
often uses regular expressions to specify labels that match
multiple files.</p>
<p style="margin-left:11%; margin-top: 1em"><i>The
following file types are defined for xserver:</i></p>
<p style="margin-left:11%; margin-top: 1em"><b>xserver_etc_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the xserver_etc_t type, if you want to store xserver
files in the /etc directories.</p>
<p style="margin-left:11%; margin-top: 1em"><b>xserver_exec_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the xserver_exec_t type, if you want to transition an
executable to the xserver_t domain. <br>
Paths:</p>
<p style="margin-left:18%;">/usr/bin/nvidia.*,
/usr/bin/Xair, /usr/bin/Xorg, /usr/bin/Xvnc,
/usr/bin/Xephyr, /usr/bin/x11vnc, /usr/X11R6/bin/X,
/usr/bin/Xwayland, /usr/X11R6/bin/Xorg,
/usr/X11R6/bin/Xipaq, /usr/libexec/Xorg.bin,
/usr/X11R6/bin/XFree86, /usr/libexec/Xorg.wrap,
/usr/X11R6/bin/Xwrapper,
/usr/libexec/gsd-backlight-helper</p>
<p style="margin-left:11%; margin-top: 1em"><b>xserver_log_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the xserver_log_t type, if you want to treat the data
as xserver log data, usually stored under the /var/log
directory. <br>
Paths:</p>
<p style="margin-left:18%;">/var/[xgkw]dm(/.*)?,
/usr/var/[xgkw]dm(/.*)?, /var/log/gdm(3)?(/.*)?,
/var/log/Xorg.*, /var/log/XFree86.*, /var/log/lightdm(/.*)?,
/var/log/nvidia-installer.log.*</p>
<p style="margin-left:11%; margin-top: 1em"><b>xserver_tmpfs_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the xserver_tmpfs_t type, if you want to store xserver
files on a tmpfs file system.</p>
<p style="margin-left:11%; margin-top: 1em"><b>xserver_var_lib_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the xserver_var_lib_t type, if you want to store the
xserver files under the /var/lib directory.</p>
<p style="margin-left:11%; margin-top: 1em"><b>xserver_var_run_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the xserver_var_run_t type, if you want to store the
xserver files under the /run or /var/run directory. <br>
Paths:</p>
<p style="margin-left:18%;">/var/run/xorg(/.*)?,
/var/run/video.rom</p>
<p style="margin-left:11%; margin-top: 1em">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 <b>semanage fcontext</b> command. This will
modify the SELinux labeling database. You will need to use
<b>restorecon</b> to apply the labels.</p>
<h2>COMMANDS
<a name="COMMANDS"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em"><b>semanage
fcontext</b> can also be used to manipulate default file
context mappings.</p>
<p style="margin-left:11%; margin-top: 1em"><b>semanage
permissive</b> can also be used to manipulate whether or not
a process type is permissive.</p>
<p style="margin-left:11%; margin-top: 1em"><b>semanage
module</b> can also be used to enable/disable/install/remove
policy modules.</p>
<p style="margin-left:11%; margin-top: 1em"><b>semanage
port</b> can also be used to manipulate the port
definitions</p>
<p style="margin-left:11%; margin-top: 1em"><b>semanage
boolean</b> can also be used to manipulate the booleans</p>
<p style="margin-left:11%; margin-top: 1em"><b>system-config-selinux</b>
is a GUI tool available to customize SELinux policy
settings.</p>
<h2>AUTHOR
<a name="AUTHOR"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">This manual
page was auto-generated using <b>sepolicy manpage .</b></p>
<h2>SEE ALSO
<a name="SEE ALSO"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">selinux(8),
xserver(8), semanage(8), restorecon(8), chcon(1),
sepolicy(8), setsebool(8)</p>
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