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<h1 align="center">ssh_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">ssh_selinux
− Security Enhanced Linux Policy for the ssh
processes</p>
<h2>DESCRIPTION
<a name="DESCRIPTION"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">Security-Enhanced
Linux secures the ssh processes via flexible mandatory
access control.</p>
<p style="margin-left:11%; margin-top: 1em">The ssh
processes execute with the ssh_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 ssh_t</b></p>
<h2>ENTRYPOINTS
<a name="ENTRYPOINTS"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">The ssh_t
SELinux type can be entered via the <b>ssh_exec_t</b> file
type.</p>
<p style="margin-left:11%; margin-top: 1em">The default
entrypoint paths for the ssh_t domain are the following:</p>
<p style="margin-left:11%; margin-top: 1em">/usr/bin/ssh,
/usr/libexec/nm-ssh-service</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 ssh
policy is very flexible allowing users to setup their ssh
processes in as secure a method as possible.</p>
<p style="margin-left:11%; margin-top: 1em">The following
process types are defined for ssh:</p>
<p style="margin-left:11%; margin-top: 1em"><b>sshd_t,
sshd_sandbox_t, sshd_net_t, ssh_keygen_t, sshd_keygen_t,
ssh_t, ssh_keysign_t</b></p>
<p style="margin-left:11%; margin-top: 1em">Note:
<b>semanage permissive -a ssh_t</b> can be used to make the
process type ssh_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. ssh policy
is extremely flexible and has several booleans that allow
you to manipulate the policy and run ssh with the tightest
access possible.</p>
<p style="margin-left:11%; margin-top: 1em">If you want to
allow host key based authentication, you must turn on the
ssh_keysign boolean. Disabled by default.</p>
<p style="margin-left:11%; margin-top: 1em"><b>setsebool -P
ssh_keysign 1</b></p>
<p style="margin-left:11%; margin-top: 1em">If you want to
allow all domains to execute in fips_mode, you must turn on
the fips_mode boolean. Enabled by default.</p>
<p style="margin-left:11%; margin-top: 1em"><b>setsebool -P
fips_mode 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
allow regular users direct dri device access, you must turn
on the selinuxuser_direct_dri_enabled boolean. Enabled by
default.</p>
<p style="margin-left:11%; margin-top: 1em"><b>setsebool -P
selinuxuser_direct_dri_enabled 1</b></p>
<p style="margin-left:11%; margin-top: 1em">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 selinuxuser_tcp_server boolean.
Disabled by default.</p>
<p style="margin-left:11%; margin-top: 1em"><b>setsebool -P
selinuxuser_tcp_server 1</b></p>
<p style="margin-left:11%; margin-top: 1em">If you want to
allows clients to write to the X server shared memory
segments, you must turn on the xserver_clients_write_xshm
boolean. Disabled by default.</p>
<p style="margin-left:11%; margin-top: 1em"><b>setsebool -P
xserver_clients_write_xshm 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
ssh policy is very flexible allowing users to setup their
ssh processes in as secure a method as possible.</p>
<p style="margin-left:11%; margin-top: 1em">The following
port types are defined for ssh: <b><br>
ssh_port_t</b></p>
<p style="margin-left:11%; margin-top: 1em">Default Defined
Ports:</p>
<p style="margin-left:26%;">tcp 22</p>
<h2>MANAGED FILES
<a name="MANAGED FILES"></a>
</h2>
<p style="margin-left:11%; margin-top: 1em">The SELinux
process type ssh_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>cifs_t</b></p>
<p style="margin-left:11%; margin-top: 1em"><b>ecryptfs_t</b></p>
<p style="margin-left:11%; margin-top: 1em">/home/[^/]+/.Private(/.*)?
<br>
/home/[^/]+/.ecryptfs(/.*)?</p>
<p style="margin-left:11%; margin-top: 1em"><b>fusefs_t</b></p>
<p style="margin-left:11%; margin-top: 1em">/var/run/user/[0-9]+/gvfs</p>
<p style="margin-left:11%; margin-top: 1em"><b>krb5_host_rcache_t</b></p>
<p style="margin-left:11%; margin-top: 1em">/var/tmp/krb5_0.rcache2
<br>
/var/cache/krb5rcache(/.*)? <br>
/var/tmp/nfs_0 <br>
/var/tmp/DNS_25 <br>
/var/tmp/host_0 <br>
/var/tmp/imap_0 <br>
/var/tmp/HTTP_23 <br>
/var/tmp/HTTP_48 <br>
/var/tmp/ldap_55 <br>
/var/tmp/ldap_487 <br>
/var/tmp/ldapmap1_0</p>
<p style="margin-left:11%; margin-top: 1em"><b>nfs_t</b></p>
<p style="margin-left:11%; margin-top: 1em"><b>ssh_tmpfs_t</b></p>
<p style="margin-left:11%; margin-top: 1em"><b>user_tmp_type</b></p>
<p style="margin-left:11%; margin-top: 1em">all user tmp
files</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
ssh policy is very flexible allowing users to setup their
ssh 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 ssh, 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 ssh_home_t
’/srv/myssh_content(/.*)?’ <br>
restorecon -R -v /srv/myssh_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 ssh:</i></p>
<p style="margin-left:11%; margin-top: 1em"><b>ssh_agent_exec_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the ssh_agent_exec_t type, if you want to transition an
executable to the ssh_agent_t domain.</p>
<p style="margin-left:11%; margin-top: 1em"><b>ssh_agent_tmp_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the ssh_agent_tmp_t type, if you want to store ssh
agent temporary files in the /tmp directories.</p>
<p style="margin-left:11%; margin-top: 1em"><b>ssh_exec_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the ssh_exec_t type, if you want to transition an
executable to the ssh_t domain. <br>
Paths:</p>
<p style="margin-left:18%;">/usr/bin/ssh,
/usr/libexec/nm-ssh-service</p>
<p style="margin-left:11%; margin-top: 1em"><b>ssh_home_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the ssh_home_t type, if you want to store ssh files in
the users home directory. <br>
Paths:</p>
<p style="margin-left:18%;">/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</p>
<p style="margin-left:11%; margin-top: 1em"><b>ssh_keygen_exec_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the ssh_keygen_exec_t type, if you want to transition
an executable to the ssh_keygen_t domain.</p>
<p style="margin-left:11%; margin-top: 1em"><b>ssh_keygen_tmp_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the ssh_keygen_tmp_t type, if you want to store ssh
keygen temporary files in the /tmp directories.</p>
<p style="margin-left:11%; margin-top: 1em"><b>ssh_keysign_exec_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the ssh_keysign_exec_t type, if you want to transition
an executable to the ssh_keysign_t domain. <br>
Paths:</p>
<p style="margin-left:18%;">/usr/lib/openssh/ssh-keysign,
/usr/libexec/openssh/ssh-keysign</p>
<p style="margin-left:11%; margin-top: 1em"><b>ssh_tmpfs_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the ssh_tmpfs_t type, if you want to store ssh files on
a tmpfs file system.</p>
<p style="margin-left:11%; margin-top: 1em"><b>sshd_exec_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the sshd_exec_t type, if you want to transition an
executable to the sshd_t domain. <br>
Paths:</p>
<p style="margin-left:18%;">/usr/sbin/sshd,
/usr/sbin/gsisshd</p>
<p style="margin-left:11%; margin-top: 1em"><b>sshd_initrc_exec_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the sshd_initrc_exec_t type, if you want to transition
an executable to the sshd_initrc_t domain.</p>
<p style="margin-left:11%; margin-top: 1em"><b>sshd_key_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the sshd_key_t type, if you want to treat the files as
sshd key data. <br>
Paths:</p>
<p style="margin-left:18%;">/etc/ssh/ssh_host.*_key,
/etc/ssh/ssh_host.*_key.pub, /etc/ssh/primes</p>
<p style="margin-left:11%; margin-top: 1em"><b>sshd_keygen_exec_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the sshd_keygen_exec_t type, if you want to transition
an executable to the sshd_keygen_t domain. <br>
Paths:</p>
<p style="margin-left:18%;">/usr/sbin/sshd-keygen,
/usr/libexec/openssh/sshd-keygen</p>
<p style="margin-left:11%; margin-top: 1em"><b>sshd_keygen_unit_file_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the sshd_keygen_unit_file_t type, if you want to treat
the files as sshd keygen unit content.</p>
<p style="margin-left:11%; margin-top: 1em"><b>sshd_keytab_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the sshd_keytab_t type, if you want to treat the files
as kerberos keytab files.</p>
<p style="margin-left:11%; margin-top: 1em"><b>sshd_tmpfs_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the sshd_tmpfs_t type, if you want to store sshd files
on a tmpfs file system.</p>
<p style="margin-left:11%; margin-top: 1em"><b>sshd_unit_file_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the sshd_unit_file_t type, if you want to treat the
files as sshd unit content.</p>
<p style="margin-left:11%; margin-top: 1em"><b>sshd_var_run_t</b></p>
<p style="margin-left:11%; margin-top: 1em">- Set files
with the sshd_var_run_t type, if you want to store the sshd
files under the /run or /var/run directory. <br>
Paths:</p>
<p style="margin-left:18%;">/var/run/sshd.pid,
/var/run/sshd.init.pid</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),
ssh(8), semanage(8), restorecon(8), chcon(1), sepolicy(8),
setsebool(8), ssh_keygen_selinux(8), ssh_keygen_selinux(8),
ssh_keysign_selinux(8), ssh_keysign_selinux(8)</p>
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