5:43 a.m.
Signed-off-by: Erik Skultety <eskultet(a)redhat.com>
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docs/auth.rst | 343 ++++++++++++++++++++++++++++++++++++++++++
docs/meson.build | 2 +-
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-<?xml version="1.0" encoding="UTF-8"?>
-<!DOCTYPE html>
-<html xmlns="http://www.w3.org/1999/xhtml">
- <body>
- <h1>Connection authentication</h1>
- <p>
- When connecting to libvirt, some connections may require client
- authentication before allowing use of the APIs. The set of possible
- authentication mechanisms is administrator controlled, independent
- of applications using libvirt. Once authenticated, libvirt can apply
- fine grained <a href="acl.html">access control</a> to the
operations
- performed by a client.
- </p>
-
- <ul id="toc"></ul>
-
- <h2><a id="Auth_client_config">Client
configuration</a></h2>
-
- <p>
- When connecting to a remote hypervisor which requires authentication,
-most libvirt applications will prompt the user for the credentials. It is
-also possible to provide a client configuration file containing all the
-authentication credentials, avoiding any interaction. Libvirt will look
-for the authentication file using the following sequence:
- </p>
- <ol>
- <li>The file path specified by the $LIBVIRT_AUTH_FILE environment
- variable.</li>
- <li>The file path specified by the "authfile=/some/file" URI
- query parameter</li>
- <li>The file $XDG_CONFIG_HOME/libvirt/auth.conf</li>
- <li>The file /etc/libvirt/auth.conf</li>
- </ol>
-
- <p>
- The auth configuration file uses the traditional
<code>".ini"</code>
- style syntax. There are two types of groups that can be present in
- the config. First there are one or more <strong>credential</strong>
- sets, which provide the actual authentication credentials. The keys
- within the group may be:
- </p>
-
- <ul>
- <li><code>username</code>: the user login name to act as. This
- is relevant for ESX, Xen, HyperV and SSH, but probably not
- the one you want to libvirtd with SASL.</li>
- <li><code>authname</code>: the name to authorize as. This is
- what is commonly required for libvirtd with SASL.</li>
- <li><code>password</code>: the secret password</li>
- <li><code>realm</code>: the domain realm for SASL, mostly
- unused</li>
- </ul>
-
- <p>
- Each set of credentials has a name, which is part of the group
- entry name. Overall the syntax is
- </p>
-
- <pre>
-[credentials-$NAME]
-credname1=value1
-credname2=value2</pre>
-
- <p>
- For example, to define two sets of credentials used for production
- and test machines, using libvirtd, and a further ESX server for dev:
- </p>
-<pre>
-[credentials-test]
-authname=fred
-password=123456
-
-[credentials-prod]
-authname=bar
-password=letmein
-
-[credentials-dev]
-username=joe
-password=hello
-
-[credentials-defgrp]
-username=defuser
-password=defpw</pre>
-
- <p>
- The second set of groups provide mappings of credentials to
- specific machine services. The config file group names compromise
- the service type and host:
- </p>
-
- <pre>
-[auth-$SERVICE-$HOSTNAME]
-credentials=$CREDENTIALS</pre>
-
- <p>
- For example, following the previous example, here is how to
- map some machines. For convenience libvirt supports a default
- mapping of credentials to machines:
- </p>
-
- <pre>
-[auth-libvirt-test1.example.com]
-credentials=test
-
-[auth-libvirt-test2.example.com]
-credentials=test
-
-[auth-libvirt-demo3.example.com]
-credentials=test
-
-[auth-libvirt-prod1.example.com]
-credentials=prod
-
-[auth-libvirt-default]
-credentials=defgrp
-
-[auth-esx-dev1.example.com]
-credentials=dev
-
-[auth-esx-default]
-credentials=defgrp</pre>
-
-
- <p>
- The following service types are known to libvirt:
- </p>
-
- <ul>
- <li><code>esx</code> - used for connections to an ESX or
- VirtualCenter server</li>
- <li><code>hyperv</code> - used for connections to an HyperV
- server</li>
- <li><code>libvirt</code> - used for connections to a libvirtd
- server, which is configured with SASL auth</li>
- <li><code>ssh</code> - used for connections to a remote QEMU
driver
- over SSH</li>
- </ul>
-
- <p>
- Applications using libvirt are free to use this same configuration
- file for storing other credentials. For example, it can be used
- to storage VNC or SPICE login credentials
- </p>
-
- <h2><a id="ACL_server_config">Server
configuration</a></h2>
- <p>
-The libvirt daemon allows the administrator to choose the authentication
-mechanisms used for client connections on each network socket independently.
-This is primarily controlled via the libvirt daemon master config file in
-<code>/etc/libvirt/libvirtd.conf</code>. Each of the libvirt sockets can
-have its authentication mechanism configured independently. There is
-currently a choice of <code>none</code>, <code>polkit</code>, and
<code>sasl</code>.
-The SASL scheme can be further configured to choose between a large
-number of different mechanisms.
-</p>
- <h2><a id="ACL_server_unix_perms">UNIX socket
permissions/group</a></h2>
- <p>
-If libvirt does not contain support for PolicyKit, then access control for
-the UNIX domain socket is done using traditional file user/group ownership
-and permissions. There are 2 sockets, one for full read-write access, the
-other for read-only access. The RW socket will be restricted (mode 0700) to
-only allow the <code>root</code> user to connect. The read-only socket will
-be open access (mode 0777) to allow any user to connect.
-</p>
- <p>
-To allow non-root users greater access, the <code>libvirtd.conf</code> file
-can be edited to change the permissions via the
<code>unix_sock_rw_perms</code>,
-config parameter and to set a user group via the
<code>unix_sock_group</code>
-parameter. For example, setting the former to mode <code>0770</code> and the
-latter <code>wheel</code> would let any user in the wheel group connect to
-the libvirt daemon.
-</p>
- <h2><a id="ACL_server_polkit">UNIX socket PolicyKit
auth</a></h2>
- <p>
-If libvirt contains support for PolicyKit, then access control options are
-more advanced. The <code>auth_unix_rw</code> parameter will default to
-<code>polkit</code>, and the file permissions will default to
<code>0777</code>
-even on the RW socket. Upon connecting to the socket, the client application
-will be required to identify itself with PolicyKit. The default policy for the
-RW daemon socket will require any application running in the current desktop
-session to authenticate using the user's password. This is akin to
<code>sudo</code>
-auth, but does not require that the client application ultimately run as root.
-Default policy will still allow any application to connect to the RO socket.
-</p>
- <p>
-The default policy can be overridden by creating a new policy file in the
-<code>/etc/polkit-1/rules.d</code> directory. Information on the options
-available can be found by reading the <code>polkit(8)</code> man page. The
-two libvirt actions are named <code>org.libvirt.unix.manage</code> for full
-management access, and <code>org.libvirt.unix.monitor</code> for read-only
-access.
-</p>
- <p>
-As an example, creating
<code>/etc/polkit-1/rules.d/80-libvirt-manage.rules</code>
-with the following gives the user <code>fred</code> full management access
-when accessing from an active local session:
- </p>
-<pre>polkit.addRule(function(action, subject) {
- if (action.id == "org.libvirt.unix.manage" &&
- subject.local && subject.active && subject.user ==
"fred") {
- return polkit.Result.YES;
- }
-});</pre>
- <p>
-Older versions of PolicyKit used policy files ending with .pkla in the
-local override directory
<code>/etc/polkit-1/localauthority/50-local.d/</code>.
-Compatibility with this older format is provided by <a
-href="https://pagure.io/polkit-pkla-compat">polkit-pkla-compat</a>. As
an
-example, this gives the user <code>fred</code> full management access:
- </p>
-<pre>[Allow fred libvirt management permissions]
-Identity=unix-user:fred
-Action=org.libvirt.unix.manage
-ResultAny=yes
-ResultInactive=yes
-ResultActive=yes</pre>
- <h2><a id="ACL_server_sasl">SASL pluggable
authentication</a></h2>
-
- <p>
-Libvirt integrates with the cyrus-sasl library to provide a pluggable authentication
-system using the SASL protocol. SASL can be used in combination with libvirtd's TLS
-or TCP socket listeners. When used with the TCP listener, the SASL mechanism is
-rqeuired to provide session encryption in addition to authentication. Only a very
-few SASL mechanisms are able to do this, and of those that can do it, only the
-GSSAPI plugin is considered acceptably secure by modern standards:
- </p>
-
- <dl>
- <dt>GSSAPI</dt>
- <dd><strong>This is the current default mechanism to use with
libvirtd</strong>.
- It uses the Kerberos v5 authentication protocol underneath, and assuming
- the Kerberos client/server are configured with modern ciphers (AES),
- it provides strong session encryption capabilities.</dd>
-
- <dt>DIGEST-MD5</dt>
- <dd>This was previously set as the default mechanism to use with libvirtd.
- It provides a simple username/password based authentication mechanism
- that includes session encryption.
- <a href="https://tools.ietf.org/html/rfc6331">RFC 6331</a>,
however,
- documents a number of serious security flaws with DIGEST-MD5 and as a
- result marks it as <code>OBSOLETE</code>. Specific concerns are that
- it is vulnerable to MITM attacks and the MD5 hash can be brute-forced
- to reveal the password. A replacement is provided via the SCRAM mechanism,
- however, note that this does not provide encryption, so the SCRAM
- mechanism can only be used on the libvirtd TLS listener.
- </dd>
-
- <dt>PASSDSS-3DES-1</dt>
- <dd>This provides a simple username/password based authentication
- mechanism that includes session encryption. The current cyrus-sasl
- implementation does not provide a way to validate the server's
- public key identity, thus it is susceptible to a MITM attacker
- impersonating the server. It is also not enabled in many OS
- distros when building SASL libraries.</dd>
-
- <dt>KERBEROS_V4</dt>
- <dd>This uses the obsolete Kerberos v4 protocol to provide both
authentication
- and session encryption. Kerberos v4 protocol has been obsolete since the
- early 1990's and has known security vulnerabilities so this will never be
- used in practice.</dd>
- </dl>
-
- <p>
- Other SASL mechanisms, not listed above, can only be used when the libvirtd
- TLS or UNIX socket listeners.
- </p>
-
- <h3><a id="ACL_server_username">Username/password
auth</a></h3>
- <p>
-As noted above, the DIGEST-MD5 mechanism is considered obsolete and should
-not be used anymore. To provide a simple username/password auth scheme on
-the libvirt UNIX socket or TLS listeners, however, it is possible to use
-the SCRAM mechanism. The <code>auth_unix_ro</code>,
<code>auth_unix_rw</code>,
-<code>auth_tls</code> config params in <code>libvirt.conf</code>
can be used
-to turn on SASL auth in these listeners.
- </p>
- <p>
-Since the libvirt SASL config file defaults to using GSSAPI (Kerberos), a
-config change is required to enable plain password auth. This is done by
-editing <code>/etc/sasl2/libvirt.conf</code> to set the
<code>mech_list</code>
-parameter to <code>scram-sha-1</code>.
- </p>
- <p>
-Out of the box, no user accounts are defined, so no clients will be able to authenticate
-on the TCP socket. Adding users and setting their passwords is done with the
<code>saslpasswd2</code>
-command. When running this command it is important to tell it that the appname is
<code>libvirt</code>.
-As an example, to add a user <code>fred</code>, run
-</p>
- <pre>
-# saslpasswd2 -a libvirt fred
-Password: xxxxxx
-Again (for verification): xxxxxx
-</pre>
- <p>
-To see a list of all accounts the <code>sasldblistusers2</code> command can
be used.
-This command expects to be given the path to the libvirt user database, which is kept
-in <code>/etc/libvirt/passwd.db</code>
-</p>
- <pre>
-# sasldblistusers2 -f /etc/libvirt/passwd.db
-fred(a)t60wlan.home.berrange.com: userPassword
-</pre>
- <p>
-Finally, to disable a user's access, the <code>saslpasswd2</code> command
can be used
-again:
-</p>
- <pre>
-# saslpasswd2 -a libvirt -d fred
-</pre>
- <h3><a id="ACL_server_kerberos">GSSAPI/Kerberos
auth</a></h3>
- <p>
-The plain TCP listener of the libvirt daemon defaults to using SASL for authentication.
-The libvirt SASL config also defaults to GSSAPI, so there is no need to edit the
-SASL config when using GSSAPI. If the libvirtd TLS or UNIX listeners are used,
-then the Kerberos session encryption will be disabled since it is not required
-in these scenarios - only the plain TCP listener needs encryption
-</p>
- <p>
-Some operating systems do not install the SASL kerberos plugin by default. It
-may be necessary to install a sub-package such as
<code>cyrus-sasl-gssapi</code>.
-To check whether the Kerberos plugin is installed run the
<code>pluginviewer</code>
-program and verify that <code>gssapi</code> is listed, e.g.:
-</p>
- <pre>
-# pluginviewer
-...snip...
-Plugin "gssapiv2" [loaded], API version: 4
- SASL mechanism: GSSAPI, best SSF: 56
- security flags: NO_ANONYMOUS|NO_PLAINTEXT|NO_ACTIVE|PASS_CREDENTIALS|MUTUAL_AUTH
- features: WANT_CLIENT_FIRST|PROXY_AUTHENTICATION|NEED_SERVER_FQDN
-</pre>
- <p>
-Next it is necessary for the administrator of the Kerberos realm to
-issue a principal for the libvirt server. There needs to be one
-principal per host running the libvirt daemon. The principal should be
-named <code>libvirt/full.hostname(a)KERBEROS.REALM</code>. This is
-typically done by running the <code>kadmin.local</code> command on the
-Kerberos server, though some Kerberos servers have alternate ways of
-setting up service principals. Once created, the principal should be
-exported to a keytab, copied to the host running the libvirt daemon
-and placed in <code>/etc/libvirt/krb5.tab</code>
-</p>
- <pre>
-# kadmin.local
-kadmin.local: add_principal libvirt/foo.example.com
-Enter password for principal "libvirt/foo.example.com(a)EXAMPLE.COM":
-Re-enter password for principal "libvirt/foo.example.com(a)EXAMPLE.COM":
-Principal "libvirt/foo.example.com(a)EXAMPLE.COM" created.
-
-kadmin.local: ktadd -k /root/libvirt-foo-example.tab
libvirt/foo.example.com(a)EXAMPLE.COM
-Entry for principal libvirt/foo.example.com(a)EXAMPLE.COM with kvno 4, encryption type
Triple DES cbc mode with HMAC/sha1 added to keytab WRFILE:/root/libvirt-foo-example.tab.
-Entry for principal libvirt/foo.example.com(a)EXAMPLE.COM with kvno 4, encryption type
ArcFour with HMAC/md5 added to keytab WRFILE:/root/libvirt-foo-example.tab.
-Entry for principal libvirt/foo.example.com(a)EXAMPLE.COM with kvno 4, encryption type DES
with HMAC/sha1 added to keytab WRFILE:/root/libvirt-foo-example.tab.
-Entry for principal libvirt/foo.example.com(a)EXAMPLE.COM with kvno 4, encryption type DES
cbc mode with RSA-MD5 added to keytab WRFILE:/root/libvirt-foo-example.tab.
-
-kadmin.local: quit
-
-# scp /root/libvirt-foo-example.tab root@foo.example.com:/etc/libvirt/krb5.tab
-# rm /root/libvirt-foo-example.tab
-</pre>
- <p>
-Any client application wishing to connect to a Kerberos enabled libvirt server
-merely needs to run <code>kinit</code> to gain a user principal. This may
well
-be done automatically when a user logs into a desktop session, if PAM is set up
-to authenticate against Kerberos.
-</p>
- </body>
-</html>
diff --git a/docs/auth.rst b/docs/auth.rst
new file mode 100644
index 0000000000..26fa6c950c
--- /dev/null
+++ b/docs/auth.rst
@@ -0,0 +1,343 @@
+=========================
+Connection authentication
+=========================
+
+When connecting to libvirt, some connections may require client
+authentication before allowing use of the APIs. The set of possible
+authentication mechanisms is administrator controlled, independent of
+applications using libvirt. Once authenticated, libvirt can apply fine
+grained `access control <acl.html>`__ to the operations performed by a
+client.
+
+.. contents::
+
+Client configuration
+--------------------
+
+When connecting to a remote hypervisor which requires authentication,
+most libvirt applications will prompt the user for the credentials. It
+is also possible to provide a client configuration file containing all
+the authentication credentials, avoiding any interaction. Libvirt will
+look for the authentication file using the following sequence:
+
+#. The file path specified by the $LIBVIRT_AUTH_FILE environment
+ variable.
+#. The file path specified by the "authfile=/some/file" URI query
+ parameter
+#. The file $XDG_CONFIG_HOME/libvirt/auth.conf
+#. The file /etc/libvirt/auth.conf
+
+The auth configuration file uses the traditional ``".ini"`` style
+syntax. There are two types of groups that can be present in the config.
+First there are one or more **credential** sets, which provide the
+actual authentication credentials. The keys within the group may be:
+
+- ``username``: the user login name to act as. This is relevant for
+ ESX, Xen, HyperV and SSH, but probably not the one you want to
+ libvirtd with SASL.
+- ``authname``: the name to authorize as. This is what is commonly
+ required for libvirtd with SASL.
+- ``password``: the secret password
+- ``realm``: the domain realm for SASL, mostly unused
+
+Each set of credentials has a name, which is part of the group entry
+name. Overall the syntax is
+
+::
+
+ [credentials-$NAME]
+ credname1=value1
+ credname2=value2
+
+For example, to define two sets of credentials used for production and
+test machines, using libvirtd, and a further ESX server for dev:
+
+::
+
+ [credentials-test]
+ authname=fred
+ password=123456
+
+ [credentials-prod]
+ authname=bar
+ password=letmein
+
+ [credentials-dev]
+ username=joe
+ password=hello
+
+ [credentials-defgrp]
+ username=defuser
+ password=defpw
+
+The second set of groups provide mappings of credentials to specific
+machine services. The config file group names compromise the service
+type and host:
+
+::
+
+ [auth-$SERVICE-$HOSTNAME]
+ credentials=$CREDENTIALS
+
+For example, following the previous example, here is how to map some
+machines. For convenience libvirt supports a default mapping of
+credentials to machines:
+
+::
+
+ [auth-libvirt-test1.example.com]
+ credentials=test
+
+ [auth-libvirt-test2.example.com]
+ credentials=test
+
+ [auth-libvirt-demo3.example.com]
+ credentials=test
+
+ [auth-libvirt-prod1.example.com]
+ credentials=prod
+
+ [auth-libvirt-default]
+ credentials=defgrp
+
+ [auth-esx-dev1.example.com]
+ credentials=dev
+
+ [auth-esx-default]
+ credentials=defgrp
+
+The following service types are known to libvirt:
+
+- ``esx`` - used for connections to an ESX or VirtualCenter server
+- ``hyperv`` - used for connections to an HyperV server
+- ``libvirt`` - used for connections to a libvirtd server, which is
+ configured with SASL auth
+- ``ssh`` - used for connections to a remote QEMU driver over SSH
+
+Applications using libvirt are free to use this same configuration file
+for storing other credentials. For example, it can be used to storage
+VNC or SPICE login credentials
+
+Server configuration
+--------------------
+
+The libvirt daemon allows the administrator to choose the authentication
+mechanisms used for client connections on each network socket
+independently. This is primarily controlled via the libvirt daemon
+master config file in ``/etc/libvirt/libvirtd.conf``. Each of the
+libvirt sockets can have its authentication mechanism configured
+independently. There is currently a choice of ``none``, ``polkit``, and
+``sasl``. The SASL scheme can be further configured to choose between a
+large number of different mechanisms.
+
+UNIX socket permissions/group
+-----------------------------
+
+If libvirt does not contain support for PolicyKit, then access control
+for the UNIX domain socket is done using traditional file user/group
+ownership and permissions. There are 2 sockets, one for full read-write
+access, the other for read-only access. The RW socket will be restricted
+(mode 0700) to only allow the ``root`` user to connect. The read-only
+socket will be open access (mode 0777) to allow any user to connect.
+
+To allow non-root users greater access, the ``libvirtd.conf`` file can
+be edited to change the permissions via the ``unix_sock_rw_perms``,
+config parameter and to set a user group via the ``unix_sock_group``
+parameter. For example, setting the former to mode ``0770`` and the
+latter ``wheel`` would let any user in the wheel group connect to the
+libvirt daemon.
+
+UNIX socket PolicyKit auth
+--------------------------
+
+If libvirt contains support for PolicyKit, then access control options
+are more advanced. The ``auth_unix_rw`` parameter will default to
+``polkit``, and the file permissions will default to ``0777`` even on
+the RW socket. Upon connecting to the socket, the client application
+will be required to identify itself with PolicyKit. The default policy
+for the RW daemon socket will require any application running in the
+current desktop session to authenticate using the user's password. This
+is akin to ``sudo`` auth, but does not require that the client
+application ultimately run as root. Default policy will still allow any
+application to connect to the RO socket.
+
+The default policy can be overridden by creating a new policy file in
+the ``/etc/polkit-1/rules.d`` directory. Information on the options
+available can be found by reading the ``polkit(8)`` man page. The two
+libvirt actions are named ``org.libvirt.unix.manage`` for full
+management access, and ``org.libvirt.unix.monitor`` for read-only
+access.
+
+As an example, creating
+``/etc/polkit-1/rules.d/80-libvirt-manage.rules`` with the following
+gives the user ``fred`` full management access when accessing from an
+active local session:
+
+::
+
+ polkit.addRule(function(action, subject) {
+ if (action.id == "org.libvirt.unix.manage" &&
+ subject.local && subject.active && subject.user ==
"fred") {
+ return polkit.Result.YES;
+ }
+ });
+
+Older versions of PolicyKit used policy files ending with .pkla in the
+local override directory ``/etc/polkit-1/localauthority/50-local.d/``.
+Compatibility with this older format is provided by
+`polkit-pkla-compat <https://pagure.io/polkit-pkla-compat>`__. As an
+example, this gives the user ``fred`` full management access:
+
+::
+
+ [Allow fred libvirt management permissions]
+ Identity=unix-user:fred
+ Action=org.libvirt.unix.manage
+ ResultAny=yes
+ ResultInactive=yes
+ ResultActive=yes
+
+SASL pluggable authentication
+-----------------------------
+
+Libvirt integrates with the cyrus-sasl library to provide a pluggable
+authentication system using the SASL protocol. SASL can be used in
+combination with libvirtd's TLS or TCP socket listeners. When used with
+the TCP listener, the SASL mechanism is rqeuired to provide session
+encryption in addition to authentication. Only a very few SASL
+mechanisms are able to do this, and of those that can do it, only the
+GSSAPI plugin is considered acceptably secure by modern standards:
+
+GSSAPI
+ **This is the current default mechanism to use with libvirtd**. It
+ uses the Kerberos v5 authentication protocol underneath, and assuming
+ the Kerberos client/server are configured with modern ciphers (AES),
+ it provides strong session encryption capabilities.
+DIGEST-MD5
+ This was previously set as the default mechanism to use with
+ libvirtd. It provides a simple username/password based authentication
+ mechanism that includes session encryption. `RFC
+ 6331 <https://tools.ietf.org/html/rfc6331>`__, however, documents a
+ number of serious security flaws with DIGEST-MD5 and as a result
+ marks it as ``OBSOLETE``. Specific concerns are that it is vulnerable
+ to MITM attacks and the MD5 hash can be brute-forced to reveal the
+ password. A replacement is provided via the SCRAM mechanism, however,
+ note that this does not provide encryption, so the SCRAM mechanism
+ can only be used on the libvirtd TLS listener.
+PASSDSS-3DES-1
+ This provides a simple username/password based authentication
+ mechanism that includes session encryption. The current cyrus-sasl
+ implementation does not provide a way to validate the server's public
+ key identity, thus it is susceptible to a MITM attacker impersonating
+ the server. It is also not enabled in many OS distros when building
+ SASL libraries.
+KERBEROS_V4
+ This uses the obsolete Kerberos v4 protocol to provide both
+ authentication and session encryption. Kerberos v4 protocol has been
+ obsolete since the early 1990's and has known security
+ vulnerabilities so this will never be used in practice.
+
+Other SASL mechanisms, not listed above, can only be used when the
+libvirtd TLS or UNIX socket listeners.
+
+Username/password auth
+~~~~~~~~~~~~~~~~~~~~~~
+
+As noted above, the DIGEST-MD5 mechanism is considered obsolete and
+should not be used anymore. To provide a simple username/password auth
+scheme on the libvirt UNIX socket or TLS listeners, however, it is
+possible to use the SCRAM mechanism. The ``auth_unix_ro``,
+``auth_unix_rw``, ``auth_tls`` config params in ``libvirt.conf`` can be
+used to turn on SASL auth in these listeners.
+
+Since the libvirt SASL config file defaults to using GSSAPI (Kerberos),
+a config change is required to enable plain password auth. This is done
+by editing ``/etc/sasl2/libvirt.conf`` to set the ``mech_list``
+parameter to ``scram-sha-1``.
+
+Out of the box, no user accounts are defined, so no clients will be able
+to authenticate on the TCP socket. Adding users and setting their
+passwords is done with the ``saslpasswd2`` command. When running this
+command it is important to tell it that the appname is ``libvirt``. As
+an example, to add a user ``fred``, run
+
+::
+
+ # saslpasswd2 -a libvirt fred
+ Password: xxxxxx
+ Again (for verification): xxxxxx
+
+To see a list of all accounts the ``sasldblistusers2`` command can be
+used. This command expects to be given the path to the libvirt user
+database, which is kept in ``/etc/libvirt/passwd.db``
+
+::
+
+ # sasldblistusers2 -f /etc/libvirt/passwd.db
+ fred(a)t60wlan.home.berrange.com: userPassword
+
+Finally, to disable a user's access, the ``saslpasswd2`` command can be
+used again:
+
+::
+
+ # saslpasswd2 -a libvirt -d fred
+
+GSSAPI/Kerberos auth
+~~~~~~~~~~~~~~~~~~~~
+
+The plain TCP listener of the libvirt daemon defaults to using SASL for
+authentication. The libvirt SASL config also defaults to GSSAPI, so
+there is no need to edit the SASL config when using GSSAPI. If the
+libvirtd TLS or UNIX listeners are used, then the Kerberos session
+encryption will be disabled since it is not required in these scenarios
+- only the plain TCP listener needs encryption
+
+Some operating systems do not install the SASL kerberos plugin by
+default. It may be necessary to install a sub-package such as
+``cyrus-sasl-gssapi``. To check whether the Kerberos plugin is installed
+run the ``pluginviewer`` program and verify that ``gssapi`` is listed,
+e.g.:
+
+::
+
+ # pluginviewer
+ ...snip...
+ Plugin "gssapiv2" [loaded], API version: 4
+ SASL mechanism: GSSAPI, best SSF: 56
+ security flags:
NO_ANONYMOUS|NO_PLAINTEXT|NO_ACTIVE|PASS_CREDENTIALS|MUTUAL_AUTH
+ features: WANT_CLIENT_FIRST|PROXY_AUTHENTICATION|NEED_SERVER_FQDN
+
+Next it is necessary for the administrator of the Kerberos realm to
+issue a principal for the libvirt server. There needs to be one
+principal per host running the libvirt daemon. The principal should be
+named ``libvirt/full.hostname(a)KERBEROS.REALM``. This is typically done
+by running the ``kadmin.local`` command on the Kerberos server, though
+some Kerberos servers have alternate ways of setting up service
+principals. Once created, the principal should be exported to a keytab,
+copied to the host running the libvirt daemon and placed in
+``/etc/libvirt/krb5.tab``
+
+::
+
+ # kadmin.local
+ kadmin.local: add_principal libvirt/foo.example.com
+ Enter password for principal "libvirt/foo.example.com(a)EXAMPLE.COM":
+ Re-enter password for principal "libvirt/foo.example.com(a)EXAMPLE.COM":
+ Principal "libvirt/foo.example.com(a)EXAMPLE.COM" created.
+
+ kadmin.local: ktadd -k /root/libvirt-foo-example.tab
libvirt/foo.example.com(a)EXAMPLE.COM
+ Entry for principal libvirt/foo.example.com(a)EXAMPLE.COM with kvno 4, encryption type
Triple DES cbc mode with HMAC/sha1 added to keytab WRFILE:/root/libvirt-foo-example.tab.
+ Entry for principal libvirt/foo.example.com(a)EXAMPLE.COM with kvno 4, encryption type
ArcFour with HMAC/md5 added to keytab WRFILE:/root/libvirt-foo-example.tab.
+ Entry for principal libvirt/foo.example.com(a)EXAMPLE.COM with kvno 4, encryption type
DES with HMAC/sha1 added to keytab WRFILE:/root/libvirt-foo-example.tab.
+ Entry for principal libvirt/foo.example.com(a)EXAMPLE.COM with kvno 4, encryption type
DES cbc mode with RSA-MD5 added to keytab WRFILE:/root/libvirt-foo-example.tab.
+
+ kadmin.local: quit
+
+ # scp /root/libvirt-foo-example.tab root@foo.example.com:/etc/libvirt/krb5.tab
+ # rm /root/libvirt-foo-example.tab
+
+Any client application wishing to connect to a Kerberos enabled libvirt
+server merely needs to run ``kinit`` to gain a user principal. This may
+well be done automatically when a user logs into a desktop session, if
+PAM is set up to authenticate against Kerberos.
diff --git a/docs/meson.build b/docs/meson.build
index f80a08112e..0179a68908 100644
--- a/docs/meson.build
+++ b/docs/meson.build
@@ -32,7 +32,6 @@ docs_assets = [
docs_html_in_files = [
'404',
- 'auth',
'bindings',
'bugs',
'cgroups',
@@ -107,6 +106,7 @@ docs_rst_files = [
'apps',
'architecture',
'auditlog',
+ 'auth',
'best-practices',
'ci',
'coding-style',
--
2.29.2