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<chapter id="saml">
    <title>SAML SSO</title>
    <para>
        Keycloak supports SAML 2.0 for registered applications.  Both POST and Redirect bindings are supported.  You can choose
        to require client signature validation and can have the server sign and/or encrypt responses as well.  We do not
        yet support logout via redirects.  All logouts happen via a background POST binding request to the application
        that will be logged out.  We do not support SAML 1.1 either.  If you want support for either of those, please
        log a JIRA request and we'll schedule it.
    </para>
    <para>
        When you create an application in the admin console, you can choose which protocol the application will log in with.
        In the application create screen, choose <literal>saml</literal> from the protocol list.  After that there
        are a bunch of configuration options.  Here is a description of each item:
    </para>
    <para>
        <variablelist>
            <varlistentry>
                <term>Client ID</term>
                <listitem>
                    <para>
                        This value must match the issuer value sent with AuthNRequests.  Keycloak will pull the issuer
                        from the Authn SAML request and match it to a client by this value.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>Include AuthnStatement</term>
                <listitem>
                    <para>
                        SAML login responses may specify the authentication method used (password, etc.) as well as
                        a timestamp of the login.  Setting this to on will include that statement in the response document.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>Multi-valued Roles</term>
                <listitem>
                    <para>
                        If this switch is off, any user role mappings will have a corresponding attribute created for it.
                        If this switch is turn on, only one role attribute will be created, but it will have
                        multiple values within in.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>Sign Documents</term>
                <listitem>
                    <para>
                        When turned on, Keycloak will sign the document using the realm's private key.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>Sign Assertions</term>
                <listitem>
                    <para>
                        With the <literal>Sign Documents</literal> switch signs the whole document.  With this setting
                        you just assign the assertions of the document.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>Signature Algorithm</term>
                <listitem>
                    <para>
                        Choose between a variety of algorithms for signing SAML documents.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>Encrypt Assertions</term>
                <listitem>
                    <para>
                        Encrypt assertions in SAML documents with the realm's private key.  The AES algorithm is used
                        with a key size of 128 bits.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>Client Signature Required</term>
                <listitem>
                    <para>
                        Expect that documents coming from a client are signed.  Keycloak will validate this signature
                        using the client keys set up in the <literal>Application Keys</literal> submenu item.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>Force POST Binding</term>
                <listitem>
                    <para>
                        By default, Keycloak will respond using the initial SAML binding of the original request.  By turning
                        on this switch, you will force Keycloak to always respond using the SAML POST Binding even if the
                        original request was the Redirect binding.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>Front Channel Logout</term>
                <listitem>
                    <para>
                        If true, this application requires a browser redirect to be able to perform a logout.  For example,
                        the application may require a cookie to be reset which could only be done by a done via a redirect.
                        If this switch is false, then Keycloak will invoke a background SAML request to logout the application.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>Force Name ID Format</term>
                <listitem>
                    <para>
                        If the request has a name ID policy, ignore it and used the value configured in the admin console
                        under Name ID Format
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>Name ID Format</term>
                <listitem>
                    <para>
                        Name ID Format for the subject.  If no name ID policy is specified in the request or if the
                        Force Name ID Format attribute is true, this value is used.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>Master SAML Processing URL</term>
                <listitem>
                    <para>
                        This URL will be used for all SAML requests and responsed directed to the SP.  It will be used
                        as the Assertion Consumer Service URL and the Single Logout Service URL.  If a login request
                        contains the Assertion Consumer Service URL, that will take precedence, but this URL must be valided
                        by a registered Valid Redirect URI pattern
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>Assertion Consumer Service POST Binding URL</term>
                <listitem>
                    <para>
                        POST Binding URL for the Assertion Consumer Service.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>Assertion Consumer Service Redirect Binding URL</term>
                <listitem>
                    <para>
                        Redirect Binding URL for the Assertion Consumer Service.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>Logout Service POST Binding URL</term>
                <listitem>
                    <para>
                        POST Binding URL for the Logout Service.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term>Logout Service Redirect Binding URL</term>
                <listitem>
                    <para>
                        Redirect Binding URL for the Logout Service.
                    </para>
                </listitem>
            </varlistentry>
        </variablelist>
    </para>
    <para>
        For login to work, Keycloak needs to be able to resolve the URL for the Assertion Consumer Service of the SP.  If
        you are relying on the SP to provide this URL in the login request, then you must register valid redirect uri patterns
        so that this URL can be validated.  You can set the Master SAML Processing URL as well, or alternatively, you can
        specify the Assertion Consumer Service URL per binding.
    </para>
    <para>
        For logout to work, you must specify a Master SAML Processing URL, or the Loging Service URL for the binding
        you want Keycloak to use.
    </para>
    <para>
        One thing to note is that roles are not treated as a hierarchy.  So, any role mappings will just be added
        to the role attributes in the SAML document using their basic name.  So, if you have multiple application roles
        you might have name collisions.  You can use the Scope Mapping menu item to control which role mappings are set
        in the response.
    </para>
    <section>
        <title>SAML Entity Descriptor</title>
        <para>
            If you go into the admin console in the application list menu page you will see an <literal>Import</literal>
            button.  If you click on that you can import SAML Service Provider definitions using the <ulink url="http://docs.oasis-open.org/security/saml/v2.0/saml-metadata-2.0-os.pdf">Entity Descriptor</ulink>
            format described in SAML 2.0.  You should review all the information there to make sure everything is set up correctly.
        </para>
        <para>
            Each realm has a URL where you can view the XML entity descriptor for the IDP.  <literal>root/auth/realms/{realm}/protocol/saml/descriptor</literal>
        </para>
    </section>
    <section>
        <title>IDP Initiated Login</title>
        <para>
            IDP Initiated Login is a feature that where you can set up a URL on the Keycloak server that will log you into a specific application/client.  To set this up
            go to the client page in the admin console of the client you want to set this up for.  Specify the <literal>IDP Initiated SSO URL Name</literal>.  This is a simple string
            with no whitespace in it.  After this you can reference your client at the following URL:  <literal>root/auth/realms/{realm}/protocol/saml/clients/{url-name}</literal>
        </para>
        <para>
            If your client requires a special relay state, you can also configure this in the admin console.  Alternatively, you can specify the relay state in a
            <literal>RelayState</literal> query parameter, i.e. :  <literal>root/auth/realms/{realm}/protocol/saml/clients/{url-name}?RelayState=thestate</literal>
        </para>
    </section>
</chapter>
