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| author | William Jon McCann <mccann@src.gnome.org> | 2007-09-11 16:48:02 +0000 |
|---|---|---|
| committer | William Jon McCann <mccann@src.gnome.org> | 2007-09-11 16:48:02 +0000 |
| commit | 1c1d9729b82a096dd35e6c36317b0b8731feeff6 (patch) | |
| tree | ccd514437fe2616b7bd12d6c1c05584e54e419c2 /docs | |
| parent | a4680f10488670e2b38ac2d7947a712a068e0c7c (diff) | |
| download | gdm-1c1d9729b82a096dd35e6c36317b0b8731feeff6.tar.gz | |
Fix distcheck
svn path=/branches/mccann-gobject/; revision=5241
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/ChangeLog | 5 | ||||
| -rw-r--r-- | docs/fr/gdm.xml | 8380 |
2 files changed, 8000 insertions, 385 deletions
diff --git a/docs/ChangeLog b/docs/ChangeLog index 72c7f741..f3a62dd9 100644 --- a/docs/ChangeLog +++ b/docs/ChangeLog @@ -1,3 +1,8 @@ +2007-09-11 William Jon McCann <mccann@jhu.edu> + + * fr/gdm.xml: + Fix distcheck. + 2007-08-31 William Jon McCann <mccann@jhu.edu> * Makefile.am: diff --git a/docs/fr/gdm.xml b/docs/fr/gdm.xml index 5321903e..43ef856a 100644 --- a/docs/fr/gdm.xml +++ b/docs/fr/gdm.xml @@ -1,387 +1,7997 @@ -<?xml version="1.0"?>
-<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
-"http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"
[
- <!ENTITY legal SYSTEM "legal.xml">
- <!ENTITY appversion "2.4.2.101" >
- <!ENTITY manrevision "2.0.1" >
- <!ENTITY date "Février 2004" >
- <!ENTITY app "Configuration de l'écran de connexion" > - <!ENTITY ug "Guide de l'utilisateur du bureau GNOME" >
+<?xml version="1.0" encoding="utf-8"?> +<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN" "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" [ +<!ENTITY legal SYSTEM "legal.xml"> +<!ENTITY version "2.19.0"> +<!ENTITY date "03/23/2007"> ]> -<!--
- (Do not remove this comment block.)
- Maintained by the GNOME Documentation Project
- http://developer.gnome.org/projects/gdp
- Template version: 2.0 beta
- Template last modified Feb 12, 2002 - --->
-<!-- =============Document Header ============================= -->
-<article id="index" lang="fr">
-<!-- please do not change the id; for translations, change lang to -->
-<!-- appropriate code -->
-
-
- <articleinfo>
- <title>Manuel de configuration de l'écran de connexion V&manrevision; </title>
-
- <copyright><year>2004</year> <holder>Sun Microsystems</holder> </copyright><!-- translators: uncomment this:
- <copyright>
- <year>2003</year>
- <holder>ME-THE-TRANSLATOR (Latin translation)</holder>
- </copyright>
- -->
-
-
- <publisher><publishername>Projet de documentation GNOME</publishername> </publisher><!-- This file contains link to license for the documentation (GNU FDL), and
- other legal stuff such as "NO WARRANTY" statement. Please do not change
- any of this. -->&legal; <authorgroup>
- <author><firstname>Sun</firstname> <surname>Équipe de documentation GNOME</surname> <affiliation><orgname>Sun Microsystems</orgname> </affiliation>
- </author><!-- This is appropriate place for other contributors: translators,
- maintainers, etc. Commented out by default.
- <othercredit role="translator">
- <firstname>Latin</firstname>
- <surname>Translator 1</surname>
- <affiliation>
- <orgname>Latin Translation Team</orgname>
- <address> <email>translator@gnome.org</email> </address>
- </affiliation>
- <contrib>Latin translation</contrib>
- </othercredit>
--->
-
- </authorgroup>
-
- <revhistory>
- <revision><revnumber>Manuel de configuration de l'écran de connexion V&manrevision;</revnumber> <date>&date;</date> <revdescription>
- <para role="author">Équipe de documentation Sun GNOME </para>
- <para role="publisher">Projet de documentation GNOME </para>
- </revdescription>
+<article id="index" lang="fr"> + <articleinfo> + <title>Gnome Display Manager Reference Manual</title> + + <revhistory> + <revision> + <revnumber>0.0</revnumber> + <date>2007-01</date> </revision> - </revhistory><releaseinfo>Le présent manuel décrit la version &appversion; de l'&app;.</releaseinfo> <legalnotice>
- <title>Votre avis</title>
- <para>Pour signaler un problème ou émettre une suggestion concernant l'application &app; ou le présent manuel, procédez comme indiqué à la <ulink url="ghelp:gnome-feedback" type="help">GNOME Feedback Page</ulink>. </para><!-- Translators may also add here feedback address for translations -->
-
- </legalnotice>
- </articleinfo><!-- ============= Document Body ============================= --><!-- ============= Introduction ============================== --><indexterm> <primary>Configuration de l'écran de connexion</primary> </indexterm> <sect1 id="gdm-introduction"> -<title>Introduction </title> -<para>Pour démarrer une session du bureau GNOME, les utilisateurs doivent se connecter pour authentifier leur identité. L'écran de connexion constitue, pour l'utilisateur, une passerelle vers le bureau GNOME. L'application <application>&app;</application> permet de paramétrer la connexion des utilisateurs au système.</para> -</sect1><!-- =========== Getting Started ============================== --> - - -
- <sect1 id="gdm-getting-started">
- <title>Démarrage</title>
- - <sect2 id="gdm-to-start">
- <title>Démarrage de &app;</title>
- - <para>Vous pouvez démarrer <application>&app;</application> en recourant à l'une des méthodes suivantes : </para> - - <variablelist> - <varlistentry><term>Menu</term> <listitem> - <para>Pour de plus amples informations sur le démarrage de <application>&app;</application> à partir d'un menu, reportez-vous à la dernière version du &ug; correspondant à votre plate-forme. </para> - </listitem> - </varlistentry> - <varlistentry><term>Ligne de commande</term> <listitem> - <para>Exécutez la commande suivante : <command>gdmsetup</command></para> - </listitem> - </varlistentry> - </variablelist> -<note><para>Vous devez disposer de privilèges d'administrateur système ou d'accès <literal>root</literal> pour configurer l'écran de connexion.</para></note> - </sect2> - - <sect2 id="gdm-when-you-start"> - <title>Lancement de &app;</title> - - <para>Lorsque vous lancez <application>&app;</application>, la boîte de dialogue suivante apparaît. </para><!-- ==== Figure ==== -->
-
- <figure id="gdm_window">
- <title>Boîte de dialogue &app; </title>
- <screenshot><mediaobject><imageobject><imagedata fileref="figures/gdm_window.png" format="PNG"/>
-
-
-
- </imageobject><textobject> <phrase>Affiche la boîte de dialogue Configuration de l'écran de connexion. Le contexte décrit le graphique.</phrase>
-
- </textobject></mediaobject></screenshot>
- </figure><!-- ==== End of Figure ==== -->
- -<para>La boîte de dialogue <application>&app;</application> contient les onglets suivants :</para> -<itemizedlist> -<listitem><para><link linkend="gdm-prefs-general">Général</link> ; </para></listitem> -<listitem><para><link linkend="gdm-prefs-standard">Bannière standard</link> ; </para></listitem> -<listitem><para><link linkend="gdm-prefs-graphical">Bannière graphique</link> ; </para></listitem> -<listitem><para><link linkend="gdm-prefs-security">Sécurité</link> ; </para></listitem> -<listitem><para><link linkend="gdm-prefs-xdmcp">XDMCP</link>. </para></listitem> -</itemizedlist> - - </sect2>
- - - </sect1><!-- ============= Customization ============================= -->
- -
-
- <sect1 id="gdm-preferences"> -<title>Préférences</title> - -<sect2 id="gdm-prefs-general"> -<title>Général </title> -<para>L'onglet Général vous permet de définir vos préférences générales concernant l'écran de connexion. </para> - - <variablelist>
- <varlistentry><term>Locale</term> <listitem>
- <para>Sélectionnez le type d'interface à utiliser pour l'écran de connexion lorsque les utilisateurs se connectent à partir d'un système local. Sélectionnez une des options proposées dans la liste déroulante :</para> -<itemizedlist> -<listitem><para>Bannière graphique : sélectionnez cette option pour utiliser un écran de connexion graphique lorsque les utilisateurs se connectent à partir d'un système local. </para> -</listitem> -<listitem><para>Bannière standard : sélectionnez cette option pour utiliser l'écran de connexion GNOME standard lorsque les utilisateurs se connectent à partir d'un système local. </para></listitem> -</itemizedlist>
- </listitem>
- </varlistentry> - <varlistentry><term>Distante</term> <listitem>
- <para>Sélectionnez le type d'interface à utiliser pour l'écran de connexion lorsque les utilisateurs se connectent à partir d'un système distant. Sélectionnez une des options proposées dans la liste déroulante :</para><itemizedlist> -<listitem><para>Bannière graphique : sélectionnez cette option pour utiliser un écran de connexion graphique lorsque les utilisateurs se connectent à partir d'un système distant. </para> -</listitem> -<listitem><para>Bannière standard : sélectionnez cette option pour utiliser l'écran de connexion GNOME standard lorsque les utilisateurs se connectent à partir d'un système distant. </para></listitem> -</itemizedlist> - </listitem>
- </varlistentry> - - <varlistentry><term>Utiliser le format 24 heures pour l'horloge</term> <listitem>
-<para>Sélectionnez cette option pour afficher l'heure au format 00.00 - 24.00 dans l'écran de connexion. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Chaîne de bienvenue</term> <listitem>
-<para>Entrez un message de bienvenue à afficher sur l'écran de connexion GNOME standard lorsque les utilisateurs se connectent à partir d'un système local. </para><note><para>Si vous souhaitez que s'affiche le nom du système dans le message de bienvenue, entrez <literal>%n</literal>dans cette zone de texte. </para></note> - </listitem>
- </varlistentry> - - <varlistentry><term>Chaîne de bienvenue distante</term> <listitem>
-<para>Entrez un message de bienvenue à afficher sur l'écran de connexion GNOME standard lorsque les utilisateurs se connectent à partir d'un système distant. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Connecter un utilisateur automatiquement au premier démarrage</term> <listitem>
-<para>Sélectionnez cette option pour connecter un utilisateur automatiquement lorsqu'il démarre le système pour la première fois. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Nom d'utilisateur de connexion automatique</term> <listitem>
-<para>La zone de liste déroulante modifiable vous permet d'entrer le nom d'utilisateur utilisé par le système pour une connexion automatique. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Connecter un utilisateur automatiquement après un nombre de secondes défini</term> <listitem>
-<para>Sélectionnez cette option pour connecter un utilisateur automatiquement après l'intervalle de temps de votre choix. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Nom d'utilisateur de connexion différée</term> <listitem>
-<para>Utilisez la zone de liste déroulante modifiable pour entrer le nom d'utilisateur utilisé par le système pour une connexion automatique après un intervalle de temps déterminé. </para> - </listitem>
- </varlistentry> - <varlistentry><term>Secondes avant la connexion</term> <listitem>
-<para>Utilisez la zone de sélection numérique pour spécifier l'intervalle de temps devant s'écouler avant de connecter l'utilisateur automatiquement. </para> - </listitem>
- </varlistentry> - -</variablelist> -</sect2> - -<sect2 id="gdm-prefs-standard"> -<title>Bannière standard </title> -<para>L'onglet Bannière standard vous permet de définir vos préférences concernant l'écran de configuration standard de GNOME. </para> - - - -<variablelist> - <varlistentry><term>Logo </term> <listitem>
-<para>Choisissez une image à afficher comme logo dans l'écran de configuration standard de GNOME. Pour choisir une image, entrez le nom de fichier correspondant dans la zone de liste déroulante modifiable. Vous pouvez également cliquer sur le bouton Parcourir pour afficher une boîte de dialogue vous permettant de choisir une image. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Afficher des images d'utilisateur sélectionnables (navigateur de figures) </term> <listitem>
-<para>Sélectionnez cette option pour afficher des images d'utilisateurs dans l'écran de configuration standard de GNOME. Si cette option est activée, les utilisateurs peuvent sélectionner une image au lieu d'entrer un nom d'utilisateur. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Pas d'arrière-plan</term> <listitem>
-<para>Sélectionnez cette option si vous ne souhaitez pas afficher d'image ou de couleur dans l'arrière-plan de l'écran de configuration standard de GNOME. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Image </term> <listitem>
-<para>Sélectionnez cette option pour afficher une image dans l'arrière-plan de l'écran de configuration standard de GNOME. Pour choisir une image, entrez le nom de fichier correspondant dans la zone de liste déroulante modifiable située à droite de la boîte de dialogue. Vous pouvez également cliquer sur le bouton Parcourir situé tout à fait à droite de la boîte de dialogue pour afficher une boîte de dialogue permettant de choisir une image. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Couleur</term> <listitem>
-<para>Sélectionnez cette option pour afficher une couleur dans l'arrière-plan de l'écran de configuration standard de GNOME. Utilisez le bouton Couleur d'arrière-plan pour la spécifier. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Ajuster l'image d'arrière-plan pour remplir l'écran</term> <listitem>
-<para>Si vous sélectionnez l'option Image, activez cette option pour ajuster l'image d'arrière-plan à l'écran de configuration standard de GNOME. Les proportions de l'image sont respectées. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Couleur uniquement pour les affichages distants</term> <listitem>
-<para>Sélectionnez cette option pour afficher une couleur en arrière-plan de l'écran de configuration standard de GNOME lorsque les utilisateurs se connectent à partir d'un système distant. </para> - </listitem>
- </varlistentry> - - - <varlistentry><term>Couleur d'arrière-plan</term> <listitem>
-<para>Si vous sélectionnez l'option Couleur ou Couleur uniquement pour les affichages distants pour l'arrière-plan, utilisez ce bouton pour spécifier la couleur. Cliquez sur le bouton Couleur d'arrière-plan pour afficher la boîte de dialogue de sélection de couleur. Choisissez la couleur requise. </para> - </listitem>
- </varlistentry> - -</variablelist> - -</sect2> -<sect2 id="gdm-prefs-graphical"> -<title>Bannière graphique </title> -<para>L'onglet Bannière graphique vous permet de définir vos préférences pour l'écran de configuration graphique de GNOME. </para> - -<variablelist> - - <varlistentry><term>Liste de thèmes</term> <listitem>
-<para>Sélectionnez un thème à afficher dans l'écran de configuration graphique. La partie droite de la boîte de dialogue fournit un aperçu du thème sélectionné. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Installer un nouveau thème</term> <listitem>
-<para>Vous pouvez ajouter un thème à la liste disponible. Le nouveau thème doit être un fichier d'archive tar zippé, c'est-à-dire qu'il doit s'agir d'un fichier <filename>.tar.gz</filename>.</para><para>Pour créer un nouveau thème, procédez comme suit :</para> -<orderedlist> -<listitem><para>Cliquez sur le bouton Installer un nouveau thème.</para></listitem> -<listitem><para>Utilisez la boîte de dialogue pour sélectionner le fichier d'archive. </para></listitem> -<listitem><para>Cliquez sur OK. </para></listitem> -</orderedlist> - </listitem>
- </varlistentry> - - <varlistentry><term>Supprimer le thème</term> <listitem>
-<para>Pour supprimer un thème, sélectionnez-le puis cliquez sur le bouton Supprimer le thème. </para> - </listitem>
- </varlistentry> - -</variablelist> - -</sect2> -<sect2 id="gdm-prefs-security"> -<title>Sécurité</title> -<para>L'onglet Sécurité vous permet de définir vos préférences concernant l'écran de connexion. </para> - -<variablelist> - <varlistentry><term>Autoriser root à se connecter en local avec GDM</term> <listitem>
-<para>Sélectionnez cette option pour autoriser les utilisateurs disposant de privilèges d'administrateurs ou d'accès <literal>root</literal> à utiliser <application>GDM</application> (<application>GNOME Display Manager</application>) pour se connecter à partir d'un système local.</para> -<note><para>Les systèmes prenant en charge les modules d'authentification enfichables (PAM) ignorent cette option. Les bibliothèques PAM déterminent si l'utilisateur est présent sur le système local. </para> -</note> - </listitem>
- </varlistentry> - - <varlistentry><term>Autoriser root à se connecter à distance avec GDM</term> <listitem>
-<para>Sélectionnez cette option pour autoriser les utilisateurs disposant de privilèges d'administrateurs ou d'accès <literal>root</literal> à utiliser <application>GDM</application> pour se connecter à partir d'un système distant. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Autoriser les connexions différées à distance</term> <listitem>
-<para>Sélectionnez cette option pour autoriser <application>GDM</application> à connecter automatiquement l'utilisateur après un intervalle de temps determiné, à partir d'un système distant. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Afficher le menu actions</term> <listitem>
-<para>Sélectionnez cette option pour permettre aux utilisateurs d'utiliser le menu Actions dans l'écran de connexion. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Autoriser la configuration à partir de l'écran de connexion</term> <listitem>
-<para>Sélectionnez cette option pour pouvoir utiliser l'élément Configurer le gestionnaire de connexion du menu Actions dans l'écran de connexion. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Autoriser l'exécution du sélecteur XDMCP à partir de l'écran de connexion</term> <listitem>
-<para>Sélectionnez cette option pour pouvoir utiliser l'élément Exécuter le sélecteur _XDMCP du menu Actions dans l'écran de connexion.</para><para>L'élément Exécuter le sélecteur _XDMCP affiche une liste d'hôtes proposant des services de gestion d'affichage. Les utilisateurs peuvent se servir cette liste pour charger un hôte de gérer une session. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Toujours interdire les connexions TCP au serveur _X (désactive toutes les connexions distantes) </term> <listitem>
-<para>Sélectionnez cette option si vous ne souhaitez pas que les utilisateurs puissent se connecter au serveur X Window System à partir de systèmes distants. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Délai entre chaque tentative (secondes)</term> <listitem>
-<para>Utilisez la zone de sélection numérique pour spécifier l'intervalle de temps devant s'écouler entre un échec de connexion et la réactivation du champ Nom d'utilisateur de l'écran de connexion.</para> -<note><para>Les systèmes prenant en charge les modules d'authentification enfichables (PAM) ignorent cette option. </para></note> - </listitem>
- </varlistentry> - -</variablelist> - - -</sect2> -<sect2 id="gdm-prefs-xdmcp"> -<title>XDMCP</title> -<para>L'onglet XDMCP vous permet de définir vos préférences concernant le protocole XDMCP (X Display Manager Control Protocol). </para> - - -<variablelist> - <varlistentry><term>Activer XDMCP</term> <listitem>
-<para>Sélectionnez cette option pour permettre à un affichage X Windows System distant de solliciter une session X Windows System à partir du système. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Accepter les requêtes indirectes</term> <listitem>
-<para>Sélectionnez cette option pour permettre aux affichages X Windows System distants ne disposant pas d'un gestionnaire d'affichage de solliciter des services de gestion d'affichage XDMCP à partir de ce système. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Écouter sur le port UDP</term> <listitem>
-<para>Utilisez la zone de sélection numérique pour spécifier le numéro de port sur lequel rechercher les requêtes UDP (User Datagram Protocol). </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Nombre maximal de requêtes en attente</term> <listitem>
-<para>Utilisez la zone de sélection numérique pour spécifier le nombre maximal de requêtes en attente émises par le système. </para><note><para>Cette option aide à éviter les attaques par déni de service. Elle permet de spécifier le nombre d'affichages pouvant être <emphasis>sollicités</emphasis> par session, mais pas le nombre total de sessions distantes autorisées par <application>GDM</application>. </para> -</note> - </listitem>
- </varlistentry> - - <varlistentry><term>Nombre maximal de requêtes indirectes en attente</term> <listitem>
-<para><application>GDM</application> crée une file d'attente des requêtes de sessions émises par le système. Utilisez la zone de sélection numérique pour spécifier le nombre maximal de requêtes de session en attente émises par des affichages ne disposant pas de gestionnaire d'affichage. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Nombre maximal de sessions distantes</term> <listitem>
-<para>Utilisez la zone de sélection numérique pour spécifier le nombre total de sessions distantes autorisées par <application>GDM</application>. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Délai d'attente maximal</term> <listitem>
-<para>Utilisez la zone de sélection numérique pour spécifier l'intervalle de temps devant s'écouler avant que <application>GDM</application> ne supprime une requête de la file d'attente. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Délai d'attente indirecte maximale</term> <listitem>
-<para>Utilisez la zone de sélection numérique pour spécifier l'intervalle de temps devant s'écouler avant que <application>GDM</application> ne supprime les affichages ne disposant pas d'un gestionnaire d'affichage de la file d'attente des affichages sollicitant une session. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Nombre d'affichages par hôte</term> <listitem>
-<para>Utilisez la zone de sélection numérique pour spécifier le nombre total de sessions distantes autorisées par <application>GDM</application> à partir d'un hôte. </para> - </listitem>
- </varlistentry> - - <varlistentry><term>Intervalle de ping (secondes)</term> <listitem>
-<para><application>GDM</application> effectue des pings sur les sessions pour vérifier si celles-ci sont toujours actives. Utilisez la zone de sélection numérique pour spécifier l'intervalle de temps devant s'écouler entre chaque ping de <application> GDM</application>. </para> - </listitem>
- </varlistentry> -</variablelist> - -</sect2> - -</sect1> -</article>
\ No newline at end of file + </revhistory> + + <abstract role="description"> + <para> + GDM is the GNOME Display Manager, a graphical login program. + </para> + </abstract> + + <authorgroup> + <author> + <firstname>Martin</firstname><othername>K.</othername> + <surname>Petersen</surname> + <affiliation> + <address><email>mkp@mkp.net</email></address> + </affiliation> + </author> + <author> + <firstname>George</firstname><surname>Lebl</surname> + <affiliation> + <address><email>jirka@5z.com</email></address> + </affiliation> + </author> + <author role="maintainer"> + <firstname>Brian</firstname><surname>Cameron</surname> + <affiliation> + <address><email>Brian.Cameron@Sun.COM</email></address> + </affiliation> + </author> + <author> + <firstname>Bill</firstname><surname>Haneman</surname> + <affiliation> + <address><email>Bill.Haneman@Sun.COM</email></address> + </affiliation> + </author> + </authorgroup> + <copyright> + <year>1998</year><year>1999</year><holder>Martin K. Petersen</holder> + </copyright> + <copyright> + <year>2001</year><year>2003</year><year>2004</year> + <holder>George Lebl</holder> + </copyright> + <copyright> + <year>2003</year> <holder>Red Hat, Inc.</holder> + </copyright> + <copyright> + <year>2003</year><year>2004</year><holder>Sun Microsystems, Inc.</holder> + </copyright> + + <legalnotice id="legalnotice"> + <para> + Permission is granted to copy, distribute and/or modify this + document under the terms of the GNU Free Documentation + License (GFDL), Version 1.1 or any later version published + by the Free Software Foundation with no Invariant Sections, + no Front-Cover Texts, and no Back-Cover Texts. You can find + a copy of the GFDL at this <ulink type="help" url="ghelp:fdl">link</ulink> or in the file COPYING-DOCS + distributed with this manual. + </para> + <para> This manual is part of a collection of GNOME manuals + distributed under the GFDL. If you want to distribute this + manual separately from the collection, you can do so by + adding a copy of the license to the manual, as described in + section 6 of the license. + </para> + + <para> + Many of the names used by companies to distinguish their + products and services are claimed as trademarks. Where those + names appear in any GNOME documentation, and the members of + the GNOME Documentation Project are made aware of those + trademarks, then the names are in capital letters or initial + capital letters. + </para> + + <para> + DOCUMENT AND MODIFIED VERSIONS OF THE DOCUMENT ARE PROVIDED + UNDER THE TERMS OF THE GNU FREE DOCUMENTATION LICENSE + WITH THE FURTHER UNDERSTANDING THAT: + + <orderedlist> + <listitem> + <para>DOCUMENT IS PROVIDED ON AN "AS IS" BASIS, + WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR + IMPLIED, INCLUDING, WITHOUT LIMITATION, WARRANTIES + THAT THE DOCUMENT OR MODIFIED VERSION OF THE + DOCUMENT IS FREE OF DEFECTS MERCHANTABLE, FIT FOR + A PARTICULAR PURPOSE OR NON-INFRINGING. THE ENTIRE + RISK AS TO THE QUALITY, ACCURACY, AND PERFORMANCE + OF THE DOCUMENT OR MODIFIED VERSION OF THE + DOCUMENT IS WITH YOU. SHOULD ANY DOCUMENT OR + MODIFIED VERSION PROVE DEFECTIVE IN ANY RESPECT, + YOU (NOT THE INITIAL WRITER, AUTHOR OR ANY + CONTRIBUTOR) ASSUME THE COST OF ANY NECESSARY + SERVICING, REPAIR OR CORRECTION. THIS DISCLAIMER + OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS + LICENSE. NO USE OF ANY DOCUMENT OR MODIFIED + VERSION OF THE DOCUMENT IS AUTHORIZED HEREUNDER + EXCEPT UNDER THIS DISCLAIMER; AND + </para> + </listitem> + <listitem> + <para>UNDER NO CIRCUMSTANCES AND UNDER NO LEGAL + THEORY, WHETHER IN TORT (INCLUDING NEGLIGENCE), + CONTRACT, OR OTHERWISE, SHALL THE AUTHOR, + INITIAL WRITER, ANY CONTRIBUTOR, OR ANY + DISTRIBUTOR OF THE DOCUMENT OR MODIFIED VERSION + OF THE DOCUMENT, OR ANY SUPPLIER OF ANY OF SUCH + PARTIES, BE LIABLE TO ANY PERSON FOR ANY + DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR + CONSEQUENTIAL DAMAGES OF ANY CHARACTER + INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS + OF GOODWILL, WORK STOPPAGE, COMPUTER FAILURE OR + MALFUNCTION, OR ANY AND ALL OTHER DAMAGES OR + LOSSES ARISING OUT OF OR RELATING TO USE OF THE + DOCUMENT AND MODIFIED VERSIONS OF THE DOCUMENT, + EVEN IF SUCH PARTY SHALL HAVE BEEN INFORMED OF + THE POSSIBILITY OF SUCH DAMAGES. + </para> + </listitem> + </orderedlist> + </para> + </legalnotice> + + + + <releaseinfo> + This manual describes version 2.19.0 of the GNOME Display Manager. + It was last updated on 03/23/2007. + </releaseinfo> + </articleinfo> + + <sect1 id="preface"> + <title>Terms and Conventions Used in This Manual</title> + + <para> + This manual describes version 2.19.0 of the GNOME Display Manager. + It was last updated on 03/23/2007. + </para> + + <para> + Chooser - A program used to select a remote host for managing a + display remotely on the local display (<command>gdmchooser</command>). + </para> + + <para> + Configurator - The configuration application + (<command>gdmsetup</command>). + </para> + + <para> + GDM - Gnome Display Manager. Used to describe the software package as a + whole. Sometimes also referred to as GDM2. + </para> + + <para> + gdm - The Gnome Display Manager daemon (<command>gdm</command>). + </para> + + <para> + Greeter - The graphical login window (<command>gdmlogin</command> or + <command>gdmgreeter</command>). + </para> + + <para> + GTK+ Greeter - The standard login window (<command>gdmlogin</command>). + </para> + + <para> + PAM - Pluggable Authentication Mechanism + </para> + + <para> + Themed Greeter - The themable login window ( + <command>gdmgreeter</command>). + </para> + + <para> + XDMCP - X Display Manage Protocol + </para> + + <para> + Paths that start with a word in angle brackets are relative to the + installation prefix. I.e. <filename><share>/pixmaps/</filename> + refers to <filename><share>/pixmaps</filename> if GDM was configured + with <command>--prefix=/usr</command>. Normally also note that + GDM is installed with <command>--sysconfigdir=<etc>/X11</command>, + meaning any path to which we refer to as + <filename><etc>/gdm/PreSession</filename> usually means + <filename><etc/X11>/gdm/PreSession</filename>. Note that for + interoperability it is recommended that you use a --prefix of + <filename>/usr</filename> and a --sysconfdir of + <filename><etc>/X11</filename>. + </para> + </sect1> + + <sect1 id="overview"> + <title>Overview</title> + + <sect2 id="introduction"> + <title> + Introduction + </title> + + <para> + The Gnome Display Manager (GDM) is a display manager that + implements all significant features required for managing + local and remote displays. GDM was written from scratch and + does not contain any XDM / X Consortium code. + </para> + + <para> + Note that GDM is highly configurable, and many configuration + settings can affect security. Issues to be aware of are highlighted + in this document and in the GDM Configuration files. + </para> + + <para> + For further information about GDM, see the + <ulink type="http" url="http://www.gnome.org/projects/gdm/"> + the GDM project website</ulink>. Please submit any bug reports or + enhancement requests to the "gdm" category in + <ulink type="http" url="http://bugzilla.gnome.org/">bugzilla.gnome.org</ulink>. + You can also send a message to the + <address><email>gdm-list@gnome.org</email></address> mail list to + discuss any issues or concerns with the GDM program. + </para> + </sect2> + + <sect2 id="stability"> + <title> + Interface Stability + </title> + + <para> + The key/value pairs defined in the GDM configuration files and + the location of these files are considered "stable" interfaces + should only change in ways that are backwards compatible. Note that + this includes functionality like the GDM scripts (Init, PreSession, + PostSession, PostLogin, XKeepsCrashing, etc.); directory locations + (ServAuthDir, etc.), system applications (SoundProgram), etc. + Some configuration values depend on OS interfaces may need to be + modified to work on a given OS. Typical examples are HaltCommand, + RebootCommand, CustomCommands, SuspendCommand, StandardXServer, Xnest, + SoundProgram, and the "command" value for each + "server-foo". + </para> + + <para> + Command-line interfaces for GDM programs installed to + <filename><bin></filename> and <filename><sbin></filename> + are considered stable. Refer to your distribution documentation to see + if there are any distribution-specific changes to these GDM interfaces + and what support exists for them. + </para> + + <para> + As of the GDM 2.15 development series, some one-dash arguments are no + longer supported. This includes the "-xdmaddress", + "-clientaddress", and "-connectionType" arguments + used by <command>gdmchooser</command>. These arguments have been + changed to now use two dashes. + </para> + + <para> + If issues are discovered that break compatibility, please file a bug + with an "urgent" priority. + </para> + </sect2> + + <sect2 id="daemonov"> + <title>The GDM Daemon</title> + + <para> + The GDM daemon is responsible for managing displays on the system. + This includes authenticating users, starting the user session, and + terminating the user session. GDM is configurable and the ways it can + be configured are described in the "Configuring GDM" section + of this document. The <filename>Init</filename>, + <filename>PostLogin</filename>, <filename>PreSession</filename>, + and <filename>PostSession</filename> scripts discussed below are + discussed in this "Configuring GDM section". + </para> + + <para> + The GDM daemon supports a UNIX domain socket protocol which can be used + to control aspects of its behavior and to query information. This + protocol is described in the "Controlling GDM" section of + this document. + </para> + + <para> + GDM can be asked to manage a display a number of ways. Local displays + are always managed when GDM starts and will be restarted when a user's + session is finished. Displays can be requested via XDMCP, flexible + displays can be requested by running the + <command>gdmflexiserver</command> command. Displays that are started + on request are not restarted on session exit. GDM also provides the + <command>gdmdynamic</command> command to allow easier management of + displays on a multi-user server. These display types are discussed + further in the next section. + </para> + + <para> + When the GDM daemon is asked to manage a display, it will fork an + X server process, then run the <filename>Init</filename> script as the + root user, and start the login GUI dialog as a slave process on the + display. GDM can be configured to use either + <command>gdmgreeter</command> (the default) or + <command>gdmlogin</command> as the GUI dialog program. The + <command>gdmlogin</command> program supports accessibility while the + <command>gdmgreeter</command> program supports greater themeability. + The GUI dialog is run as the unpriviledged "gdm" user/group + which is described in the "Security" section below. The GUI + dialog communicates with the daemon via a sockets protocol and via + standard input/output. The slave, for example passes the username and + password information to the GDM daemon via standard input/output so + the daemon can handle the actual authentication. + </para> + + <para> + The login GUI dialog screen allows the user to select which session + they wish to start and which language they wish to use. Sessions are + defined by files that end in the .desktop extension and more + information about these files can be found in the + "Configuration" section. The user enters their name and + password and if these successfully authenticate, GDM will start the + requested session for the user. It is possible to configure GDM to + avoid the authentication process by turning on the Automatic or Timed + Login features in the GDM configuration. The login GUI can also be + configured to provide additional features to the user, such as the + Face Browser; the ability to halt, restart, or suspend the system; + and/or edit the login configuration (after entering the root password). + </para> + + <para> + GDM, by default, will use Pluggable Authentication Modules (PAM) for + authentication, but can also support regular crypt and shadow passwords + on legacy systems. After authenticating a user, the daemon runs the + <filename>PostLogin</filename> script as root, and forks a slave + process to start the requested session. This slave process runs the + <filename>PreSession</filename> script as root, sets up the user's + environment, and starts the requested session. GDM keeps track of the + user's default session and language in the user's + <filename>~/.dmrc</filename> and will use these defaults if the user + did not pick a session or language in the login GUI. On Solaris, GDM + (since version 2.8.0.3) uses the SDTLOGIN interface after user + authentication to tell the X server to be restarted as the user instead + of as root for added security. When the user's session exits, the GDM + daemon will run the <filename>PostSession</filename> script as root. + </para> + + <para> + Note that, by default, GDM uses the "gdm" service name for + normal login and the "gdm-autologin" service name for + automatic login. The <filename>PamStack</filename> configuration + option can be used to specify a different service name. For example, + if "foo" is specified, then GDM will use the "foo" + service name for normal login and "foo-autologin" for + automatic login. + </para> + + <para> + For those looking at the code, the gdm_verify_user function in + <filename>daemon/verify-pam.c</filename> is used for normal login + and the gdm_verify_setup_user function is used for automatic login. + </para> + </sect2> + + <sect2 id="displaytypes"> + <title>Different Display Types</title> + + <para> + GDM supports three different display types: static (local) displays, + flexible (on-demand) displays, and XDMCP (remote) displays. The + "X Server Definitions" subsection of the + "Configuration" section explains how the X server is + configured for different displays. + </para> + + <para> + Static (local) displays are always started by the daemon, and when they + die or are killed, they are restarted. GDM can run as many of these + as needed. GDM can also manage displays on which it does not manage a + GUI login, thus GDM can be used for supporting X terminals. + The "Local Static X Display Configuration" subsection of + the "Configuration" section describes how Static (local) + displays are defined. + </para> + + <para> + Flexible, or on demand displays are only available to users logged + in on the console. Starting a flexible display will lock the current + user session and will show a new login screen over the current running + session. If at least one flexible display is already running, and the + user requests another, then a dialog will display showing existing + flexible displays. The user can choose to switch back to a previous + display or start a new flexible display. If the user switches back + to a previous display, they will need to enter the password in the + lock screen program to return to their session. The GDM configuration + file specifies the maximum number of flexible displays allowed on the + system. + </para> + + <para> + Flexible displays may be started by running the + <command>gdmflexiserver</command> command, or via calling the GDM + socket protocol directly. Some lock screen programs provide a button + to start a new flexible session. This allows a user to start a new + session even if the screen was left locked. The GNOME Fast User + Switch applet also uses the socket protocol to provide an applet + interface on the GNOME panel for managing user displays quickly. + Flexible displays are not restarted when the user session ends. + Flexible displays require virtual terminal (VT) support in the kernel, + and will not be available if not supported (such as on Solaris). + </para> + + <para> + The <filename>FlexibleXServers</filename>, + <filename>FirstVT=7</filename>, <filename>VTAllocation</filename>, + and <filename>FlexiReapDelayMinutes</filename> configuration settings + are used to configure how flexible displays operate. + </para> + + <para> + Nested displays are available to users even if not logged in on the + console. Nested displays launch a login screen in a window in the + user's current session. This can be useful if the user has more + than one account on a machine and wishes to login to the other + account without disrupting their current session. Nested displays + may be started by running the <command>gdmflexiserver -n</command> + command or via calling the GDM socket protocol directly. Nested + displays require that the X server supports a nested X server command + like Xnest or Xephyr. The <filename>Xnest</filename> configuration + option is used to configure how nested displays operate + </para> + + <para> + The <command>gdmdynamic</command> is similar to + <command>gdmflexiserver</command> in the sense that it allows the + user to manage displays dynamically. However displays started with + <command>gdmdynamic</command> are treated as local displays, so + they are restarted automatically when the session exits. This + command is intended to be used in multi-user server environments + (many displays connected to a single server). In other words, + this command allows the displays to be managed without hardcoding + the display information in the "Local Static X Display + Configuration" section of the configuration file. This + is useful to support the ability of adding new displays to the + server without needing to restart GDM, for example. + </para> + + <para> + The last display type is the XDMCP remote displays which are described + in the next section. Remote hosts can connect to GDM and present the + login screen if this is enabled. Some things are different for + remote sessions. For example, the Actions menu which allows you to + shut down, restart, suspend, or configure GDM are not shown. + </para> + + </sect2> + + <sect2 id="xdmcp"> + <title> + XDMCP + </title> + + <para> + The GDM daemon can be configured to listen for and manage X Display + Manage Protocol (XDMCP) requests from remote displays. By default + XDMCP support is turned off, but can be enabled if desired. If GDM is + built with TCP Wrapper support, then the daemon will only grant access + to hosts specified in the GDM service section in the TCP Wrappers + configuration file. + </para> + + <para> + GDM includes several measures making it more resistant to denial of + service attacks on the XDMCP service. A lot of the protocol + parameters, handshaking timeouts etc. can be fine tuned. The defaults + should work for most systems, however. Do not change them unless you + know what you are doing. + </para> + + <para> + GDM listens to UDP port 177 and will respond to QUERY and + BROADCAST_QUERY requests by sending a WILLING packet to the originator. + </para> + + <para> + GDM can also be configured to honor INDIRECT queries and present a + host chooser to the remote display. GDM will remember the user's + choice and forward subsequent requests to the chosen manager. GDM + also supports an extension to the protocol which will make it forget + the redirection once the user's connection succeeds. This extension + is only supported if both daemons are GDM. It is transparent and + will be ignored by XDM or other daemons that implement XDMCP. + </para> + + <para> + If XDMCP seems to not be working, make sure that all machines are + specified in <filename>/etc/hosts</filename>. + </para> + + <para> + Refer to the "Security" section for information about + security concerns when using XDMCP. + </para> + </sect2> + + <sect2 id="secureremote"> + <title> + Securing Remote Connection Through SSH + </title> + <para> + As explained in the "Security" section, XDMCP does not use + any kind of encryption and as such is inherently insecure. As XDMCP + uses UDP as a network transport layer, it is not possible to simply + secure it through an SSH tunnel. + </para> + + <para> + To remedy this problem, gdm can be configured at compilation-time with + the option --enable-secureremote, in which case gdm proposes as a + built-in session a session called "Secure Remote Connection". + Starting such a session allows the user to enter the name or the + address of the host on which to connect; provided the said host runs an + SSH server, the user then gets connected to the server on which the + default X session is started and displayed on the local host. + </para> + + <para> + Using this session allows a much more secure network connection and + only necessitates to have an SSH server running on the remote host. + </para> + </sect2> + + <sect2 id="gtkgreeter"> + <title>The GTK+ Greeter</title> + + <para> + The GTK+ Greeter is the default graphical user interface that is + presented to the user. The greeter contains a menu at the top, an + optional face browser, an optional logo and a text entry widget. + This greeter has full accessibility support, and should be used + by users with accessibility needs. + </para> + + <para> + The text entry field is used for entering logins, passwords, + passphrases etc. <command>gdmlogin</command> is controlled by the + underlying daemon and is basically stateless. The daemon controls the + greeter through a simple protocol where it can ask the greeter for a + text string with echo turned on or off. Similarly, the daemon can + change the label above the text entry widget to correspond to the + value the authentication system wants the user to enter. + </para> + + <para> + The menu bar in the top of the greeter enables the user to select the + requested session type/desktop environment, select an appropriate + locale/language, halt/restart/suspend the computer, configure GDM + (given the user knows the root password), change the GTK+ theme, or + start an XDMCP chooser. + </para> + + <para> + The greeter can optionally display a logo in the login window. The + image must be in a format readable to the gdk-pixbuf library (GIF, + JPG, PNG, TIFF, XPM and possibly others), and it must be readable to + the GDM user. See the <filename>Logo</filename> option in the + reference section below for details. + </para> + </sect2> + + <sect2 id="themedgreeter"> + <title>The Themed Greeter</title> + + <para> + The Themed Greeter is a greeter interface that takes up the whole + screen and is very themable. Themes can be selected and new themes + can be installed by the configuration application or by setting the + <filename>GraphicalTheme</filename> configuration key. The Themed + Greeter is much like the GTK+ Greeter in that it is controlled by + the underlying daemon, is stateless, and is controlled by the + daemon using the same simple protocol. + </para> + + <para> + The look and feel of this greeter is really controlled by the theme and + so the user interface elements that are present may be different. The + only thing that must always be present is the text entry field as + described above in the GTK+ Greeter. The theme can include buttons + that allow the user to select an appropriate locale/language, + halt/restart/suspend the computer, configure GDM (given the user + knows the root password), or start an XDMCP chooser. + </para> + + <para> + You can always get a menu of available actions by pressing the F10 key. + This can be useful if the theme doesn't provide certain buttons when + you wish to do some action allowed by the GDM configuration. + </para> + </sect2> + + <sect2 id="facebrowser"> + <title>The GDM Face Browser</title> + + <para> + GDM supports a face browser which will display a list of users who + can login and an icon for each user. Starting with version 2.18.1 + the <filename>Browser</filename> configuration option must be set + to "true" for this function to be available. In previous + versions it was only required when using the GTK+ Greeter. When + using the Themed Greeter, the Face Browser is only available if the + GDM theme includes a "userlist" item type. + </para> + + <para> + By default, the face browser is disabled since revealing usernames on + the login screen is not appropriate on many systems for security + reasons. Also GDM requires some setup to specify which users should + be visible. Setup can be done on the "Users" tab in + <command>gdmsetup</command>. This feature is most practical to use + on a system with a smaller number of users. + </para> + + <para> + The icons used by GDM can be installed globally by the sysadmin or can + be located in the users' home directories. If installed globally + they should be in the <filename><share>/pixmaps/faces/</filename> + directory (though this can be configured with the + <filename>GlobalFaceDir</filename> configuration option) and the + filename should be the name of the user, optionally with a + <filename>.png</filename> appended. Face icons placed in the global + face directory must be readable to the GDM user. However, the daemon, + proxies user pictures to the greeter and thus those do not have be be + readable by the "gdm" user, but root. + </para> + + <para> + Users may run the <command>gdmphotosetup</command> command to + configure the image to use for their userid. This program properly + scales the file down if it is larger than the + <filename>MaxIconWidth</filename> or + <filename>MaxIconHeight</filename> configuration options and places the + icon in a file called <filename>~/.face</filename>. Although + <command>gdmphotosetup</command> scales user images automatically, + this does not guarantee that user images are properly scaled since + a user may create their <filename>~/.face</filename> file by hand. + </para> + + <para> + GDM will first look for the user's face image in + <filename>~/.face</filename>. If not found, it will try + <filename>~/.face.icon</filename>. If still not found, it will + use the value defined for "face/picture=" in the + <filename>~/.gnome2/gdm</filename> file. Lastly, it will try + <filename>~/.gnome2/photo</filename> and + <filename>~/.gnome/photo</filename> which are deprecated and + supported for backwards compatibility. + </para> + + <para> + If a user has no defined face image, GDM will use the + "stock_person" icon defined in the current GTK+ theme. If no + such image is defined, it will fallback to the image specified in the + <filename>DefaultFace</filename> configuration option, normally + <filename><share>/pixmaps/nobody.png</filename>. + </para> + + <para> + Please note that loading and scaling face icons located in user home + directories can be a very time-consuming task. Since it not + practical to load images over NIS or NFS, GDM does not attempt to + load face images from remote home directories. Furthermore, GDM will + give up loading face images after 5 seconds of activity and will + only display the users whose pictures it has gotten so far. The + <filename>Include</filename> configuration option can be used to + specify a set of users who should appear on the face browser. As + long as the users to include is of a reasonable size, there should + not be a problem with GDM being unable to access the face images. + To work around such problems, it is recommended to place face images + in the directory specified by the <filename>GlobalFaceDir</filename> + configuration option. + </para> + + <para> + To control the users who get displayed in the face browser, there are + a number of configuration options that can be used. If the + <filename>IncludeAll</filename> option is set to true, then the + password file will be scanned and all users will be displayed. If + <filename>IncludeAll</filename> option is set to false, then the + <filename>Include</filename> option should contain a list of users + separated by commas. Only the users specified will be displayed. + Any user listed in the <filename>Exclude</filename> option and users + whose UID's is lower than <filename>MinimalUID</filename> will be + filtered out regardless of the <filename>IncludeAll</filename> + setting. <filename>IncludeAll</filename> is not recommended + for systems where the passwords are loaded over a network (such as + when NIS is used), since it can be very slow to load more than a + small number of users over the network.. + </para> + + <para> + When the browser is turned on, valid usernames on the computer are + inherently exposed to a potential intruder. This may be a bad idea if + you do not know who can get to a login screen. This is especially + true if you run XDMCP (turned off by default). + </para> + </sect2> + + <sect2 id="logging"> + <title>Logging</title> + + <para> + GDM itself will use syslog to log errors or status. It can also log + debugging information, which can be useful for tracking down problems + if GDM is not working properly. This can be enabled in the + configuration file. + </para> + + <para> + Output from the various X servers is stored in the GDM log directory, + which is configurable, but is usually + <filename><var>/log/gdm/</filename>. The output from the + session can be found in a file called + <filename><display>.log</filename>. Four older files are also + stored with <filename>.1</filename> through + <filename>.4</filename> appended. These will be rotated as new + sessions on that display are started. You can use these logs to view + what the X server said when it started up. + </para> + + <para> + The output from the user session is redirected to + <filename>~/.xsession-errors</filename> + before even the <filename>PreSession</filename> script is started. So + it is not really necessary to redirect this again in the session setup + script. As is usually done. If the user session lasted less then + 10 seconds, GDM assumes that the session crashed and allows the user to + view this file in a dialog before returning to the login screen. + This way the user can view the session errors from the last session + and correct the problem this way. + </para> + + <para> + You can suppress the 10 second warning by returning code 66 from the + <filename>Xsession</filename>script or from your session binary (the + default <filename>Xsession</filename> script propagates those codes + back). This is useful if you have some sort of special logins for + which it is not an error to return less then 10 seconds later, or if + you setup the session to already display some error message and the + GDM message would be confusing and redundant. + </para> + + <para> + The session output is piped through the GDM daemon and so the + <filename>~/.xsession-errors</filename> file is capped at about + 200 kilobytes by GDM to prevent a possible denial of service attack + on the session. An application could perhaps on reading some wrong + data print out warnings or errors on the stderr or stdout. This could + perhaps fill up the user's home directory making it necessary to log + out and back into their session to clear this. This could be + especially nasty if quotas are set. GDM also correctly traps the XFSZ + signal and stops writing the file, which would lead to killed sessions + if the file was redirected in the old fashioned way from the script. + </para> + + <para> + Note that some distributors seem to override the + <filename>~/.xsession-errors</filename> redirection and do it + themselves in their own Xsession script (set by the + <filename>BaseXsession</filename> configuration key) which means that + GDM will not be able to trap the output and cap this file. You also + lose output from the <filename>PreSession</filename> script which can + make debugging things harder to figure out as perhaps useful output + of what is wrong will not be printed out. See the description of the + <filename>BaseXsession</filename> configuration key for more + information, especially on how to handle multiple display managers + using the same script. + </para> + + <para> + Note that if the session is a failsafe session, or if GDM can't open + this file for some reason, then a fallback file will be created in the + <filename>/tmp</filename> directory named + <filename>/tmp/xses-<user>.XXXXXX</filename> where the + <filename>XXXXXX</filename> are some random characters. + </para> + + <para> + If you run a system with quotas set, it would be good to delete the + <filename>~/.xsession-errors</filename> in the + <filename>PostSession</filename> script. Such that this log file + doesn't unnecessarily stay around. + </para> + </sect2> + + <sect2 id="fileaccess"> + <title>Accessing Files</title> + + <para> + In general GDM is very reluctant regarding reading/writing of user + files (such as the <filename>~/.dmrc</filename>, + <filename>~/.face</filename>, + <filename>~/.xsession-errors</filename>, and + <filename>~/.Xauthority</filename> files). For instance it refuses to + access anything but regular files. Links, sockets and devices are + ignored. The value of the <filename>RelaxPermissions</filename> + parameter determines whether GDM should accept files writable by the + user's group or others. These are ignored by default. + </para> + + <para> + All operations on user files are done with the effective user id of the + user. If the sanity check fails on the user's + <filename>.Xauthority</filename> file, a fallback cookie is created in + the directory specified by the <filename>UserAuthFBDir</filename> + configuration setting (<filename>/tmp</filename> by default). + </para> + + <para> + Finally, the sysadmin can specify the maximum file size GDM should + accept, and, if the face browser is enabled, a tunable maximum icon + size is also enforced. On large systems it is still advised to turn + off the face browser for performance reasons. Looking up icons in + home directories, scaling and rendering face icons can take a long + time. + </para> + </sect2> + + <sect2 id="performance"> + <title>GDM Performance</title> + + <para> + To speed performance it is possible to build GDM so that it will + preload libraries when GDM first displays a greeter program. This + has been shown to speed first time login since these libraries can + be loaded into memory while the user types in their username and + password. + </para> + + <para> + To use this feature, configure GDM with the + <command>--with-prefetch</command> option. This will cause GDM to + install the <command>gdmprefetch</command> program to the + <filename>libexecdir</filename> directory, install the + <filename>gdmprefetchlist</filename> to the + <filename><etc>/gdm</filename> directory, and set the + <filename>PreFetchProgram</filename> configuration variable so that the + <command>gdmprefetch</command> program is called with the default + <filename>gdmprefetchlist</filename> file. The default + <filename>gdmprefetchlist</filename> file was optimized + for a GNOME desktop running on Solaris, so may need fine-tuning on + other systems. Alternative prefetchlist files can be contributed + to the "gdm" category in + <ulink type="http" url="http://bugzilla.gnome.org/">bugzilla.gnome.org</ulink>, + so that they can be included in future GDM releases. + </para> + </sect2> + </sect1> + + <sect1 id="security"> + <title>Security</title> + + <sect2 id="PAM"> + <title> + PAM + </title> + + <para> + GDM uses PAM for login authentication, though if your machine does not + support PAM you can build GDM to work with the password database and + the crypt library function. + </para> + + <para> + PAM stands for Pluggable Authentication Module, and is used by most + programs that request authentication on your computer. It allows the + administrator to configure different authentication behavior for + different programs. + </para> + + <para> + Some GDM features (like turning on automatic login) may require that + you update your PAM configuration. PAM configuration has different, + but similar, interfaces on different operating systems, so check your + pam.d or pam.conf man page for details. Be sure that you read the + PAM documentation (e.g. pam.d/pam.conf man page) and are comfortable + with the security implications of any changes you intend to make to + your configuration. + </para> + + <para> + If there is no entry for GDM in your system's PAM configuration file, + then features like automatic login may not work. Not having an entry + will cause GDM to use default behavior, conservative settings are + recommended and probably shipped with your distribution. + </para> + + <para> + If you wish to make GDM work with other types of authentication + mechanisms (such as a SmartCard), then you should implement this by + using a PAM service module for the desired authentication type rather + than by trying to modify the GDM code directly. Refer to the PAM + documentation on your system. This issue has been discussed on the + <address><email>gdm-list@gnome.org</email></address> mail list, + so you can refer to the list archives for more information. + </para> + + <para> + For example, an effective way to implement such an exotic + authentication mechanism would be to have a daemon running + on the server listening to the authentication device (e.g. + USB key, fingerprint reader, etc.). When the device + announces that it has received input, then the daemon can + set the <filename>PamStack</filename> configuration value + using per-display configuration, and restart the greeter + with the PAM stack that works with this device. This avoids + needing to hack the display manager code directly to support + the feature. + </para> + </sect2> + + <sect2 id="gdmuser"> + <title>The GDM User</title> + + <para> + For security reasons a dedicated user and group id are required for + proper operation! The need to be able to write Xauth files is why user + "nobody" is not appropriate for gdm. + </para> + + <para> + The GDM daemon normally runs as root, as does the slave. However GDM + should also have a dedicated user id and a group id which it uses for + its graphical interfaces such as <command>gdmgreeter</command> and + <command>gdmlogin</command>. These are configured via the + <filename>User</filename> and <filename>Group</filename> + configuration options in the GDM configuration files. The user and + group should be created before running "make install". By + default GDM assumes the user and the group are called "gdm". + </para> + + <para> + This userid is used to run the GDM GUI programs required for login. + All functionality that requires root authority is done by the GDM + daemon process. This design ensures that if the GUI programs are + somehow exploited, only the dedicated user privileges are available. + </para> + + <para> + It should however be noted that the GDM user and group have some + privileges that make them somewhat dangerous. For one, they have + access to the X server authorization directory. It must be able to + read and write Xauth keys to <filename><var>/lib/gdm</filename>. + This directory should have root:gdm ownership and 1770 permissions. + Running "make install" will set this directory to these + values. The GDM daemon process will reset this directory to proper + ownership/permissions if it is somehow not set properly. + </para> + + <para> + The danger is that someone who gains the GDM user/group privileges can + then connect to any session. So you should not, under any + circumstances, make this some user/group which may be easy to get + access to, such as the user <filename>nobody</filename>. Users who + gain access to the "gdm" user could also modify the Xauth + keys causing Denial-Of-Service attacks. Also if a person gains the + ability to run programs as the user "gdm", it would be + possible to snoop on running GDM processes, including usernames and + passwords as they are being typed in. + </para> + + <para> + Distributions and system administrators using GDM are expected to setup + the dedicated user properly. It is recommended that this userid be + configured to disallow login and to not have a default shell. + Distributions and system administrators should set up the filesystem to + ensure that the GDM user does not have read or write access to + sensitive files. + </para> + </sect2> + + <sect2 id="xauth"> + <title>X Server Authentication Scheme</title> + + <para> + The X server authorization directory (the + <filename>ServAuthDir</filename>) is used for a host of random + internal data in addition to the X server authorization files, and the + naming is really a relic of history. GDM daemon enforces this + directory to be owned by <filename>root.gdm</filename> with the + permissions of 1770. This way, only root and the GDM group have write + access to this directory, but the GDM group cannot remove the root + owned files from this directory, such as the X server authorization + files. + </para> + + <para> + GDM by default doesn't trust the X server authorization directory and + treats it in the same way as the temporary directory with respect to + creating files. This way someone breaking the GDM user cannot mount + attacks by creating links in this directory. Similarly the X server + log directory is treated safely, but that directory should really be + owned and writable only by root. + </para> + + <para> + GDM only supports the MIT-MAGIC-COOKIE-1 X server authentication + scheme. Normally little is gained from the other schemes, and no + effort has been made to implement them so far. Be especially + careful about using XDMCP because the X server authentication cookie + goes over the wire as clear text. If snooping is possible, then an + attacker could simply snoop your authentication password as you log in, + regardless of the authentication scheme being used. If snooping is + possible and undesirable, then you should use ssh for tunneling an X + connection rather then using XDMCP. You could think of XDMCP as a sort + of graphical telnet, having the same security issues. + </para> + + <para> + On the upside, GDM's random number generation is very conservative and + GDM goes to extraordinary measures to truly get a 128 bit random + number, using hardware random number generators (if available), plus + the current time (in microsecond precision), a 20 byte array of + pseudorandom numbers, process pid's, and other random information + (possibly using <filename>/dev/audio</filename> or + <filename>/dev/mem</filename> if hardware random generators are not + available) to create a large buffer and then run MD5 digest on this. + Obviously, all this work is wasted if you send this cookie over an open + network or store it on an NFS directory (see + <filename>UserAuthDir</filename> configuration key). So be careful + about where you use remote X display. + </para> + </sect2> + + <sect2 id="firewall"> + <title>Firewall Security</title> + + <para> + Even though GDM tries to outsmart potential attackers trying to take + advantage of XDMCP, it is still advised that you block the XDMCP port + (normally UDP port 177) on your firewall unless you really need it. + GDM guards against DoS (Denial of Service) attacks, but the X protocol + is still inherently insecure and should only be used in controlled + environments. Also each remote connection takes up lots of resources, + so it is much easier to DoS via XDMCP then a webserver. + </para> + + <para> + It is also wise to block all of the X Server ports. These are TCP + ports 6000 + the display number of course) on your firewall. Note that + GDM will use display numbers 20 and higher for flexible on-demand + servers. + </para> + + <para> + X is not a very safe protocol for leaving on the net, and XDMCP is + even less safe. + </para> + </sect2> + + <sect2 id="nfssecurity"> + <title>GDM Security With NFS</title> + + <para> + Note that NFS traffic really goes "over the wire" and thus + can be snooped. When accessing the user's X authorization file + (<filename>~/.Xauthority</filename>), GDM will try to open the file + for reading as root. If it fails, GDM will conclude that it is on an + NFS mount and it will automatically use + <filename>UserAuthFBDir</filename>, which by default is set to + <filename>/tmp</filename>. This behavior can be changed by setting the + <filename>NeverPlaceCookiesOnNFS</filename> in the + <filename>[security]</filename> section to false. + </para> + </sect2> + + <sect2 id="xdmcpsecurity"> + <title>XDMCP Security</title> + + <para> + Even though your display is protected by cookies, XEvents and thus + keystrokes typed when entering passwords will still go over the wire in + clear text. It is trivial to capture these. + </para> + + <para> + XDMCP is primarily useful for running thin clients such as in terminal + labs. Those thin clients will only ever need the network to access + the server, and so it seems like the best security policy to have + those thin clients on a separate network that cannot be accessed by + the outside world, and can only connect to the server. The only point + from which you need to access outside is the server. + </para> + + <para> + The above sections "X Server Authentication Scheme" and + "Firewall Security" also contain important information about + using XDMCP securely. The next section also discusses how to set up + XDMCP access control. + </para> + + <para> + To workaround the inherent insecurity of XDMCP, gdm proposes a default + built-in session that uses SSH to encrypt the remote connection. See + the section "Securing remote connection through SSH" above. + </para> + </sect2> + + <sect2 id="xdmcpaccess"> + <title>XDMCP Access Control</title> + + <para> + XDMCP access control is done using TCP wrappers. It is possible to + compile GDM without TCP wrappers however, so you should test your + configuration and verify that they work. + </para> + + <para> + You should use the daemon name <command>gdm</command> in the + <filename><etc>/hosts.allow</filename> and + <filename><etc>/hosts.deny</filename> files. For example to + deny computers from <filename>.evil.domain</filename> from logging in, + then add + </para> +<screen> +gdm: .evil.domain +</screen> + <para> + to <filename><etc>/hosts.deny</filename>. You may also need + to add + </para> +<screen> +gdm: .your.domain +</screen> + <para> + to your <filename><etc>/hosts.allow</filename> if you normally + disallow all services from all hosts. See the + <ulink type="help" url="man:hosts.allow">hosts.allow(5)</ulink> man + page for details. + </para> + </sect2> + + <sect2 id="rbac"> + <title>RBAC (Role Based Access Control)</title> + + <para> + If GDM is compiled with RBAC support, then the + <filename>RBACSystemCommandKeys</filename> configuration option can be + used to specify the RBAC key to be used to determine if the user has + authority to use commands. This is supported for the Shutdown, + Reboot, Suspend, and Custom Commands that appear in the GDM greeter + and via the <command>gdmflexiserver</command> QUERY_LOGOUT_ACTION, + SET_LOGOUT_ACTION, and SET_SAFE_LOGOUT_ACTION commands. The greeter + will only display the option if the gdm user (specified by the + <filename>User</filename> configuration option) has permission + via RBAC. Users will only be able to use the + <command>gdmflexiserver</command> commands if the user has + permission via RBAC. + </para> + </sect2> + </sect1> + + <sect1 id="consolekit"> + <title>Support for ConsoleKit</title> + + <para> + GDM includes support for publishing user login information with the user + and login session accounting framework known as ConsoleKit. ConsoleKit + is able to keep track of all the users currently logged in. In this + respect, it can be used as a replacement for the utmp or utmpx files that + are available on most Unix-like operating systems. + </para> + + <para> + When GDM is about to create a new login process for a user it will call + a privileged method of ConsoleKit in order to open a new session for this + user. At this time GDM also provides ConsoleKit with information about + this user session such as: the user ID, the X11 Display name that will be + associated with the session, the host-name from which the session + originates (useful in the case of an XDMCP session), whether or not this + session is local, etc. As the entity that initiates the user process, + GDM is in a unique position know and to be trusted to provide these bits + of information about the user session. The use of this privileged method + is restricted by the use of D-Bus system message bus security policy. + </para> + + <para> + In the case where a user with an existing session and has authenticated + at GDM and requests to resume that existing session GDM calls a + privileged method of ConsoleKit to unlock that session. The exact + details of what happens when the session receives this unlock signal is + undefined and session-specific. However, most sessions will unlock a + screensaver in response. + </para> + + <para> + When the user chooses to log out, or if GDM or the session quit + unexpectedly the user session will be unregistered from ConsoleKit. + </para> + + <para> + If support for ConsoleKit is not desired it can be disabled at build + time using the "--with-console-kit=no" option when running + configure. + </para> + + </sect1> + + <sect1 id="gdmsetupusage"> + <title>Using gdmsetup To Configure GDM</title> + + <para> + The <command>gdmsetup</command> application can be used to configure GDM. + If you believe running root-owned GUI's causes security risk, then you + would want to always edit the files by hand and not use + <command>gdmsetup</command>. Editing the files by hand is explained in + the "Configuration" section of this document. Note that + <command>gdmsetup</command> does not support changing of all + configuration variables, so it may be necessary to edit the files by + hand for some configurations. + </para> + + <para> + The <command>gdmsetup</command> program has five tabs: Local, Remote, + Accessibility, Security, and Users, described below. In parenthesis is + information about which GDM configuration key is affected by each GUI + choice. Refer to the "Configuration" section of this manual + and the comments in the GDM System Defaults Configuration File for + additional details about each key. + </para> + + <sect2 id="gdmsetuplocaltab"> + <title>Local Tab</title> + + <para> + The Local tab is used for controlling the appearance of GDM for + local/static displays (non-XDMCP remote connections). The choices + available in this tab depend on the setting of the "Style" + combobox. This combobox is used to determine whether the + "Plain" or "Themed" greeter GUI is used. The + differences between these greeter programs are explained in the + "Overview" section of this document. + </para> + + <para> + If the "Style" choice is "Plain", then GDM will + use the <command>gdmlogin</command> program as the GUI + (daemon/Greeter). When this choice is selected, + <command>gdmsetup</command> allows the user to select whether the + background is an image or solid color (greeter/BackgroundType). If + image is selected, there is a file selection button to pick the image + file (greeter/BackgroundImage) and a checkbox to scale the image to fit + the screen (greeter/BackgroundImageScaleToFit). If solid color is + selected, there is a button available to allow the color selection + (greeter/BackgroundColor). Also, the user may select the logo image + that appears in gdmlogin (greeter/Logo). + </para> + + <para> + If the "Style" choice is "Plain with face browser", + then the <command>gdmlogin</command> program is used as the GUI + (daemon/Greeter) and the face browser is turned on (greeter/Browser). + The Face Browser is explained in the "Overview" section. + Otherwise, the choices are the same as when the "Style" + choice is "Plain". Additional setup in the Users tab may be + necessary to choose which users appear in the Face Browser. + </para> + + <para> + If the "Style" choice is "Themed", then the + <command>gdmgreeter</command> program is used as the GUI + (daemon/Greeter). When this choice is selected, + <command>gdmsetup</command> allows the user to select the theme to be + used (greeter/GraphicalTheme). Note that the checkbox to the left + of the theme's name must be checked for a theme to be selected. + Information about the theme's author and copyright are shown for the + highlighted theme. The "Remove" button can be used to delete + the highlighted theme. The "Add" button can be used to add + new themes to the system. For a new theme to be added it must be + in tar or compressed tar format. The "Background color" + displayed when GDM starts (and if the theme has transparent elements) + can be selected (greeter/GraphicalThemedColor). The "Theme" + combo box may be set to "Random from selected" to display a + random theme for each login (greeter/GraphicalThemeRand and + greeter/GraphicalThemes). To use random themes, select each theme that + you wish to be displayed. By default this combobox is set to + "Selected only", so that only a single theme may be selected + and be used. + </para> + + <para> + If the "Style" choice is "Themed with face + browser", then the <command>gdmgreeter</command> program is used + as the GUI (daemon/Greeter) and the face browser is turned on + (greeter/Browser) if supported by the theme. The Face Browser is + explained in the Overview section. Otherwise, the choices are the + same as when the "Style" choice is "Themed". + Additional setup in the Users tab may be necessary to choose which + users appear in the Face Browser. + </para> + + <para> + Regardless of the "Style" choice, the user may also select + whether the Actions menu is visible (greeter/SystemMenu), whether the + Actions menu includes the choice to start <command>gdmsetup</command> + (greeter/ConfigAvailable), and whether the Action menu includes the + choice to start <command>gdmchooser</command> to run a remote XDMCP + login session (greeter/ChooserButton). Note that the root password + must be entered to start <command>gdmsetup</command> from the login + screen if it is enabled. Also the Welcome message displayed for local + sessions may be selected (greeter/DefaultWelcome and greeter/Welcome). + The Welcome message can contain the character sequences described in + the "Text Node" section of the "Themed Greeter" + section of this manual. + </para> + </sect2> + + <sect2 id="gdmsetupremotetab"> + <title>Remote Tab</title> + + <para> + The Remote tab controls the appearance of the GDM for users logging + in via XDMCP. By default XDMCP is disabled, and users should be + comfortable with the XDMCP-related sections of the Security section + of this document before enabling it. This tab includes a + "Style" combobox which can be used to turn on XDMCP and + control the appearance of GDM for remote users (gui/RemoteGreeter + and xdmcp/Enable). The user may specify to use either the same + greeter as used on the Local tab, or the other Greeter program. If + the Face Browser setting is true on the Local tab, then it will also + be true for the Remote tab. If the Face Browser setting is + false on the Local tab, then it will also be false for the Remote + tab. It is recommended that the "Plain" GUI be used for + remote connections since it is more lightweight and tends to have + better performance across a network. + </para> + + <para> + If Remote login is enabled, then the user can specify the remote + Welcome Message to be displayed (greeter/DefaultRemoteWelcome and + greeter/RemoteWelcome). This welcome message is separate from the + Local welcome message and can have a different value. The Welcome + message can contain the character sequences described in the + "Text Node" section of the "Themed Greeter" + section of this manual. + </para> + + <para> + If the "Style" choice is "Same as Local" and the + local selection is "Plain" or "Plain with face + browser", then the user may select whether background images + should be displayed for remote logins + (greeter/BackgroundRemoteOnlyColor). + </para> + + <para> + If the "Style" choice is enabled and set to a different + value than the Local tab, then the user has the same configuration + choices as found on the Local tab except that the System Menu + choices are not available since this is never available for remote + logins for security purposes. + </para> + + <para> + If Remote login is enabled, there is a "Configure XDMCP" + button which displays a dialog allowing the user to set XDMCP + configuration, including whether indirect requests are honored + (xdmcp/HonorIndirect), UDP port (xdmcp/Port), maximum pending requests + (xdmcp/MaxPending), maximum pending indirect requests + (xmdcp/MaxPendingIndirect), maximum remote sessions + (xdmcp/MaxSessions), maximum wait time (xdmcp/MaxWait), maximum + indirect wait time (xdmcp/MaxWaitIndirect), displays per host + (xdmcp/DisplaysPerHost), and ping interval (xdmcp/PingIntervalSeconds). + The default settings are standard settings and should only be changed + by someone who understands the ramifications of the change. + </para> + </sect2> + + <sect2 id="gdmsetupaccessibilitytab"> + <title>Accessibility Tab</title> + + <para> + The Accessibility tab is used to turn on Accessibility features in GDM. + "Enable accessible login" (daemon/AddGtkModules and + daemon/GtkModulesList) turns on GDM's gesture listeners which are + explained in the "Accessibility" section of this document. + There is also a checkbox to allow users to change the theme when using + the Plain greeter (gui/AllowGtkThemeChange). This feature allows GDM + users to switch the theme to the HighContrast or LowContrast themes if + needed. The user may also select whether GDM should play a sound when + the login screen is ready, when login is successful and when login has + failed. File chooser buttons are used to select the sound file to be + played, and the "Play" button can be used to sample the + sound. + </para> + </sect2> + + <sect2 id="gdmsetupsecuritytab"> + <title>Security Tab</title> + + <para> + The Security tab allows the user to turn on Automatic and Timed login, + which user is logged in via an automatic or timed login, and the + timed login delay (daemon/AutomaticLoginEnable, daemon/AutomaticLogin, + daemon/TimedLoginEnable, daemon/TimedLogin, and daemon/TimedLoginDelay). + If automatic login is turned on, then the specified user will + immediately log in on reboot without GDM asking for username/password. + If the user logs out of their session, GDM will start and ask for + username and password to log back in. If TimedLogin is turned on, then + GDM will log into the specified user after a specified number of + seconds. The user may enable Timed Login for remote (XDMCP) + connections by checking the "Allow remote timed logins" + checkbox. + </para> + + <para> + On this tab, the user may select whether the system administrator user + can log in, and whether the system administrator user can log in + via remote (XDMCP) connections (security/AllowRoot and + security/AllowRemoteRoot). The user may turn on GDM debug + (debug/Enable) which causes debug messages to be sent to the system + log. Debug should only be used when diagnosing a problem and not be + left on when not needed. The "Deny TCP connections to + X server" choice will disable X forwarding if selected + (security/DisallowTCP). A login retry delay (security/RetryDelay) can + be set to cause GDM to wait a number of seconds after a failed login. + </para> + + <para> + The "Configure X Server" button can be used to specify how + GDM manages each display. The "Servers" combobox shows what + server definitions are available (Standard, Terminal, and Chooser by + default). Refer to the "X Server Definitions" section of + the "Configuration" section for more information about how + to create new Server Definitions. + </para> + + <para> + For any server type, the user may modify the "Server Name" + (server/name), the "Command" (server/command) to be used to + launch the X server, whether the server type will "Launch" + (server/chooser) the greeter or chooser GUI after starting the + X server, whether GDM handles this type (normally only set to false + when logging into a Terminal session type), and whether the session + type supports "Flexible" (server/flexible) sessions. + </para> + + <para> + The "Servers To Start" section shows what server type is + displayed for each display on the machine. Users may click on the + "Add/Modify" button to add a new display to the list or to + modify a selected display. This simply corresponds each physical + display with the Server Definition to be used for managing that + display. The "Remove" button may be used to remove a + display from the list. + </para> + </sect2> + + <sect2 id="gdmsetupuserstab"> + <title>Users Tab</title> + + <para> + The Users tab controls which users appear in the Face Browser. If the + "Include all users from /etc/password" checkbox is selected, + then all users (with a userid above greeter/MinimalUID and not in the + Exclude list) are displayed. If this checkbox is not selected, then + users must be added to the "Include" list. Users in the + "Exclude" list are never displayed. The "Add" and + "Remove" buttons are used to add a new user to the list or + remove a selected user from the list. The "Apply User + Changes" button must be pressed after the "Include" and + "Exclude" lists have been modified. The left and right + arrow buttons between the "Include" and "Exclude" + lists can be used to move a selected user from one list to the other. + </para> + </sect2> + </sect1> + + <sect1 id="configuration"> + <title>Configuration</title> + + <para> + GDM has powerful configuration management. System default configuration + is stored in the GDM System Defaults Configuration File and user changes + to the default configuration are stored in the GDM Custom Configuration + File. This allows sysadmins to store the GDM System Defaults + Configuration File on a shared filesystem, so a single file can be used + to control configuration for multiple machines. GDM also supports + per-display configuration for GUI-related keys. + </para> + + <para> + The <command>gdmsetup</command> is a GUI program you can use to edit the + GDM configuration. This program may also be launched directly from the + login screen if the greeter/ConfigAvailable key is set to "true" + Not all keys in the GDM configuration file are supported in the GUI, so + you may need to edit the configuration files by hand to edit these keys. + If you believe running root-owned GUI's causes security risk, then you + would want to always edit the files by hand. This program does not + support setting per-display configuration, so per-display configuration + files must be set up by hand. + </para> + + <para> + Aside from the GDM System Defaults Configuration File, the other GDM + configuration files are located, by default, in the + <filename><etc>/gdm/</filename> folder or its subdirectories. + Note that the location of many configuration files are defined in the + GDM configuration files, so check the GDM System Defaults Configuration + File and the GDM Custom Configuration File if the files are not in the + locations specified in this document. + </para> + + <para> + Listing of the config directory contents: + </para> + +<screen> +custom.conf +locale.alias +Xsession +XKeepsCrashing +modules/ +Init/ +PostLogin/ +PreSession/ +PostSession/ +</screen> + + <para> + <filename>locale.alias</filename> is a file which looks much like the + system locale alias but, in fact, is not the same. This is a list + of all languages that may be on your system. All languages are + checked to see if they exist before displaying them in the Language + Selection dialog in the login GUI. Only those that exist are displayed. + </para> + + <para> + <filename>Xsession</filename> is a script which sets up a user session + and then executes the user's choice of session. Note that the session + script is typically started via the <filename>desktop</filename> + file associated with the session the user has picked. Some + sessions may start the user's session via a different mechanism than + the <filename>Xsession</filename> script, so please check the + appropriate <filename>desktop</filename> before assuming a session + startup issue is being caused by this file. + </para> + + <para> + <filename>XKeepsCrashing</filename> is a script which gets run when the + X server keeps crashing and we cannot recover. The shipped default + script will work with most Linux distributions and can run the X + configuration application provided the person on the console knows the + root password. + </para> + + <para> + Accessibility modules are configured in the <filename>modules/</filename> + subdirectory, and are a separate topic. Read the default files provided, + they have adequate documentation. Again normally the default install + is given in the files with <filename>factory</filename> in their name, + and those files are not read, they are just there for you so you can + always revert to default config. + </para> + + <para> + Files describing available GDM session follow the freedesktop.org + desktop file specification. The <filename>.desktop</filename>-style + files are installed to <filename><etc>/X11/sessions/</filename>. + This directory is also read by the KDE desktop manager (KDM) for common + configuration. Next the directory + <filename><share>/gdm/BuiltInSessions/</filename> is read for + GDM specific built-in sessions (KDM hardcodes these at time of + this writing). Lastly the default setup will also read + <filename><share>/xsessions/</filename> (which should be + <filename><share>/xsessions/</filename> if you really wish to + cooperate with KDM) where desktop packages can install their session + files. The directories under the <filename><etc></filename> should + be reserved for configuration. The desktop file specification approach + makes it easy for package management systems to install window managers + and different session types without requiring the sysadmin to edit files. + See the <filename>SessionDesktopDir</filename> configuration key for + changing the paths. It used to be that GDM stored its built in + sessions in <filename><etc>/dm/Sessions/</filename> but this is + deprecated as of 2.5.90.0. Note that prior to version 2.4.4.2 only the + <filename><etc>/dm/Sessions/</filename> was being read. + </para> + + <para> + A session can be disabled (if it was installed in + <filename><share>/xsessions/</filename>) by adding an identically + named <filename>.desktop</filename> to one of the directories earlier in + the path (likely <filename><etc>/X11/sessions</filename>) and using + <filename>Hidden=true</filename> in that file. + </para> + + <para> + GDM uses the optional key <filename>X-Gdm-XserverArgs</filename> in + session files to specify additional arguments to be passed to the + X server. For example, the entry + <filename>X-Gdm-XserverArgs=-depth 16</filename> will start the + X server with a color depth of 16 bits. Any such additional arguments + are ignored when using a Nested display (when GDM is launched in a + window). + </para> + + <sect2 id="scriptdirs"> + <title>The Script Directories</title> + + <para> + In this section we will explain the <filename>Init</filename>, + <filename>PostLogin</filename>, <filename>PreSession</filename> and + <filename>PostSession</filename> directories as they are very similar. + </para> + + <para> + When the X server has been successfully started, GDM will try to run + the script called <filename>Init/<displayname></filename>. I.e. + <filename>Init/:0</filename> for the first local display. If this file + is not found, GDM will attempt to to run + <filename>Init/<hostname></filename>. I.e. + <filename>Init/somehost</filename>. + If this still is not found, GDM will try + <filename>Init/XDMCP</filename> for all XDMCP logins or + <filename>Init/Flexi</filename> for all on demand flexible + displays. If none of the above were found, GDM will run + <filename>Init/Default</filename>. The script will be run as root and + GDM blocks until it terminates. Use the <filename>Init/*</filename> + script for applications that are supposed to run alongside with the GDM + login window. xconsole for instance. Commands to set the background + etc. go in this file too. + </para> + + <para> + It is up to the sysadmin to decide whether clients started by the Init + script should be killed before starting the user session. This is + controlled with the <filename>KillInitClients</filename> configuration + option. + </para> + + <para> + When the user has been successfully authenticated GDM tries the + scripts in the <filename>PostLogin</filename> directory in the same + manner as for the <filename>Init</filename> directory. This is done + before any session setup is done, and so this would be the script where + you might setup the home directory if you need to (though you should + use the <filename>pam_mount</filename> module if you can for this). + You have the <filename>$USER</filename> and + <filename>$DISPLAY</filename> environment variables set for this + script, and again it is run as root. The script should return 0 on + success as otherwise the user won't be logged in. This is not true for + failsafe session however. + </para> + + <para> + After the user session has been setup from the GDM side of things, GDM + will run the scripts in the <filename>PreSession</filename> directory, + again in the same manner as the <filename>Init</filename> directory. + Use this script for local session management or accounting stuff. The + <filename>$USER</filename> environment variable contains the login of + the authenticated user and <filename>$DISPLAY</filename> is set to the + current display. The script should return 0 on success. Any other + value will cause GDM to terminate the current login process. This is + not true for failsafe sessions however. Also + <filename>$X_SERVERS</filename> environmental variable is set and this + points to a fake generated X servers file for use with the sessreg + accounting application. + </para> + + <para> + After this the base <filename>Xsession</filename> script is run with + the selected session executable as the first argument. This is run as + the user, and really this is the user session. The available session + executables are taken from the <filename>Exec=</filename> line in the + <filename>.desktop</filename> files in the path specified by + <filename>SessionDesktopDir</filename>. Usually this path is + <filename><etc>/X11/sessions/:<etc>/dm/Sessions:/usr/share/xsessions/</filename>. + The first found file is used. The user either picks from these + sessions or GDM will look inside the file <filename>~/.dmrc</filename> + for the stored preference. + </para> + + <para> + This script should really load the user's profile and generally do all + the voodoo that is needed to launch a session. Since many systems + reset the language selections done by GDM, GDM will also set the + <filename>$GDM_LANG</filename> variable to the selected language. You + can use this to reset the language environmental variables after you + run the user's profile. If the user elected to use the system language, + then <filename>$GDM_LANG</filename> is not set. + </para> + + <para> + When the user terminates his session, the + <filename>PostSession</filename> script will be run. Again operation + is similar to <filename>Init</filename>, <filename>PostLogin</filename> + and <filename>PreSession</filename>. Again the script will be run with + root privileges, the slave daemon will block and the + <filename>$USER</filename> environment variable will contain the name + of the user who just logged out and <filename>$DISPLAY</filename> will + be set to the display the user used, however note that the X server for + this display may already be dead and so you shouldn't try to access it. + Also <filename>$X_SERVERS</filename> environmental variable is set and + this points to a fake generated X servers file for use with the sessreg + accounting application. + </para> + + <para> + Note that the <filename>PostSession</filename> script will be run + even when the display fails to respond due to an I/O error or + similar. Thus, there is no guarantee that X applications will work + during script execution. + </para> + + <para> + Except for the <filename>Xsession</filename> script all of these + scripts will also have the environment variable + <filename>$RUNNING_UNDER_GDM</filename> set to + <filename>yes</filename>, so that you could perhaps use similar + scripts for different display managers. The + <filename>Xsession</filename> will always have the + <filename>$GDMSESSION</filename> set to the basename of the + session that the user chose to run without the + <filename>.desktop</filename> extension. In addition + <filename>$DESKTOP_SESSION</filename> is also set to the same value + and in fact this will also be set by KDM in future versions. + </para> + + <para> + Neither of the <filename>Init</filename>, + <filename>PostLogin</filename>, <filename>PreSession</filename> or + <filename>PostSession</filename> scripts are necessary and can be left + out. The <filename>Xsession</filename> script is however required as + well as at least one session <filename>.desktop</filename> file. + </para> + </sect2> + + <sect2 id="configfile"> + <title>The Configuration Files - GDM System Defaults Configuration File + and GDM Custom Configuraiton File</title> + + <para> + GDM uses two configuration files: the GDM System Defaults Configuration + File (<filename><share>/gdm/defaults.conf</filename>) and the + GDM Custom Configuration File + (<filename><etc>/gdm/custom.conf</filename>). The GDM System + Defaults File contains the default configuration choices for GDM, and + should not be modified by the user. The GDM Custom Configuration File + is where users may specify their custom configuration choices. + If a configuration option is not defined in either file, GDM will + default to the value described in the comments in the GDM System + Defaults Configuration File. + </para> + + <para> + Both configuration files are divided into sections each containing + variables that define the behavior for a specific part of the GDM + suite. Refer to the comments in the GDM System Defaults Configuration + File for additional information about each configuration setting. + </para> + + <para> + GDM also supports per-display configuration for parameters in the + "gui", "greeter" sections of the configuration file + Also the security/PamStack key may be customized per-display. + Per-display configuration is specified by creating a file named + <filename><etc>/gdm/custom.conf<display num></filename>. + In this file the section and keys to use on this display can be + specified. For example, configuration overrides for display + ":103" would be stored in the file + <filename><etc>/gdm/custom.conf:0</filename>. Per-display + configuration is supported in GDM 2.14.6 and later. + </para> + + <para> + To change configuration by hand, edit the GDM Custom Configuration File + or per-display configuration file and make sure the keyname=value + pair you want is included in the appropriate section. For example, + to change the value for the "Greeter" key in the + "daemon" section, make sure the daemon section of the GDM + Custom Configuration File or per-display configuration file includes + the "[daemon]" section followed by the key and value + change desired. As in this example: + </para> + +<screen> +[daemon] +Greeter=/usr/lib/gdmgreeter +</screen> + + <para> + The <command>gdmsetup</command> command can be used to modify the GDM + Custom Configuration File. Note the <command>gdmsetup</command> is + intended to be run as root, so users who feel it is insecure to run + GUI programs as root should edit the configuration files by hand. + </para> + + <para> + The GDM daemon <command>--config</command> argument may instead be used + to specify a different configuration file location. The GDM daemon + must be restarted to change the configuration file being used. Also + when building GDM, the location of the configuration files may be + specified via the <command>--with-defaults-conf</command> and + <command>--with-custom-conf</command> configuration options. + </para> + + <para> + Previous to GDM 2.13.0.4 only the + <filename><etc>/gdm/gdm.conf</filename> existed. For best + backwards compatibility, this file will be used instead of the GDM + Custom Configuration File if it exists on your system. If upgrading + to the new version of GDM, "make install" will check to see + if the <filename><etc>/gdm/gdm.conf</filename> file is different + than the <filename><etc>/gdm/factory-gdm.conf</filename> file. + If so, the <filename><etc>/gdm/gdm.conf</filename> file will be + automatically copied to + <filename><etc>/gdm/custom.conf</filename> to preserve any + configuration changes. + </para> + + <para> + Distributions should edit the GDM System Defaults Configuration File to + establish default configuration values, so that they are preserved as + defaults and not modified by users modifying the GDM Custom + Configuration File. Note that distributions may modify the GDM System + Defaults Configuration File on update to improve usability, security, + etc. So any changes made to this file may be lost. + </para> + + <para> + The GDM System Defaults Configuration File and the GDM Custom + Configuration File follow the standard <filename>.ini</filename> style + configuration file syntax. Keywords in brackets define sections, + strings before an equal sign (=) are variables and the data after + equal sign represents their value. Empty lines or lines starting with + the hash mark (#) are ignored. The graphical configurator will try to + preserve both comments (lines with a hash mark) and the overall + structure of the file so you can intermix using the GUI or hand + editing the configuration file. + </para> + + <para> + The following configuration keys are supported in GDM: + </para> + + <sect3 id="daemonsection"> + <title>Daemon Configuration</title> + + <variablelist> + <title>[daemon]</title> + + <varlistentry> + <term>AddGtkModules</term> + <listitem> + <synopsis>AddGtkModules=false</synopsis> + <para> + If true, then enables <command>gdmgreeter</command> or + <command>gdmlogin</command> to be launched with additional + Gtk+ modules. This is useful when extra features are required + such as accessible login. Note that only "trusted" + modules should be used to minimize security issues. + </para> + <para> + If true, then the registry daemon + <command>at-spi-registryd</command> + will be launched by <command>gdmgreeter</command> or + <command>gdmlogin</command> starting with version GDM 2.17. + </para> + <para> + Usually this is used for accessibility modules. The modules + which are loaded are specified with the + <filename>GtkModulesList</filename> key. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>AllowLogoutActions</term> + <listitem> + <synopsis>AllowLogoutActions=HALT;REBOOT;SHUTDOWN;SUSPEND;CUSTOM_CMD</synopsis> + <para> + Specify which actions are supported by the QUERY_LOGOUT_ACTION, + SET_LOGOUT_ACTION, and SET_SAFE_LOGOUT_ACTION + <command>gdmflexiserver</command> commands. Valid values are + HALT, REBOOT, SHUTDOWN, SUSPEND, and CUSTOM_CMD and these + should be separated by semicolons. This allows certain + options to be disabled if desired. Refer to the related + <filename>SystemCommandsInMenu</filename> and + <filename>RBACSystemCommandKeys</filename> configuration + options. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>AlwaysLoginCurrentSession</term> + <listitem> + <synopsis>AlwaysLoginCurrentSession=true</synopsis> + <para> + If true, then when the user logs in and already has an + existing session, then they are connected to that session + rather than starting a new session. This only works for + sessions running on VTs (Virtual Terminals) started with + gdmflexiserver, and not with XDMCP. Note that VTs are not + supported on all operating systems. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>AutomaticLoginEnable</term> + <listitem> + <synopsis>AutomaticLoginEnable=false</synopsis> + <para> + If the user given in AutomaticLogin should be logged in upon + first bootup. No password will be asked. This is useful + for single user workstations where local console security + is not an issue. Also could be useful for public terminals, + although there see <filename>TimedLogin</filename>. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>AutomaticLogin</term> + <listitem> + <synopsis>AutomaticLogin=</synopsis> + <para> + This user should be automatically logged in on first bootup. + AutomaticLoginEnable must be true and this must be + a valid user for this to happen. "root" can never be + autologged in however and gdm will just refuse to do it even + if you set it up. + </para> + + <para> + The following control chars are recognized within the + specified name: + </para> + + <para> + %% — the `%' character + </para> + + <para> + %d — display's name + </para> + + <para> + %h — display's hostname + </para> + + <para> + Alternatively, the name may end with a vertical bar |, the + pipe symbol. The name is then used as a application to execute + which returns the desired username on standard output. If an + empty or otherwise invalid username is returned, automatic + login is not performed. This feature is typically used when + several remote displays are used as internet kiosks, with a + specific user to automatically login for each display. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>BaseXsession</term> + <listitem> + <synopsis>BaseXsession=<etc>/gdm/Xsession</synopsis> + <para> + This is the base X session file. When a user logs in, this + script will be run with the selected session as the first + argument. The selected session will be the + <filename>Exec=</filename> from the + <filename>.desktop</filename> file of the session. + </para> + + <para> + If you wish to use the same script for several different + display managers, and wish to have some of the script run only + for GDM, then you can check the presence of the + <filename>GDMSESSION</filename> environmental variable. This + will always be set to the basename of + <filename>.desktop</filename> (without the extension) file that + is being used for this session, and will only be set for GDM + sessions. Previously some scripts were checking for + <filename>GDM_LANG</filename>, but that is only set when the + user picks a non-system default language. + </para> + + <para> + This script should take care of doing the "login" for + the user and so it should source the + <filename><etc>/profile</filename> and friends. The + standard script shipped with GDM sources the files in this + order: <filename><etc>/profile</filename> then + <filename>~/.profile</filename> then + <filename><etc>/xprofile</filename> and finally + <filename>~/.xprofile</filename>. Note that different + distributions may change this however. Sometimes users + personal setup will be in <filename>~/.bash_profile</filename>, + however broken that is. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Chooser</term> + <listitem> + <synopsis>Chooser=<bin>/gdmchooser</synopsis> + <para> + Full path and name of the chooser executable followed by + optional arguments. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Configurator</term> + <listitem> + <synopsis>Configurator=<bin>/gdmsetup --disable-sound --disable-crash-dialog</synopsis> + <para> + The pathname to the configurator binary. If the greeter + <filename>ConfigAvailable</filename> option is set to true then + run this binary when somebody chooses Configuration from the + Actions menu. Of course GDM will first ask for root password + however. And it will never allow this to happen from a remote + display. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>ConsoleCannotHandle</term> + <listitem> + <synopsis>ConsoleCannotHandle=am,ar,az,bn,el,fa,gu,hi,ja,ko,ml,mr,pa,ta,zh</synopsis> + <para> + These are the languages that the console cannot handle because + of font issues. Here we mean the text console, not X. This + is only used when there are errors to report and we cannot + start X. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>ConsoleNotify</term> + <listitem> + <synopsis>ConsoleNotify=true</synopsis> + <para> + If false, gdm will not display a message dialog on the + console when an error happens. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>DefaultPath</term> + <listitem> + <synopsis>DefaultPath=defaultpath (value set by configure)</synopsis> + <para> + Specifies the path which will be set in the user's session. + This value will be overridden with the value from + <filename>/etc/default/login</filename> if it contains + "ROOT=<pathname>". If the + <filename>/etc/default/login</filename> file exists, but + contains no value for ROOT, the value as defined in the GDM + configuration will be be used. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>DefaultSession</term> + <listitem> + <synopsis>DefaultSession=gnome.desktop</synopsis> + <para> + The session that is used by default if the user does not have + a saved preference and has picked 'Last' from the list of + sessions. Note that 'Last' need not be displayed, see + the <filename>ShowLastSession</filename> key. + </para> + </listitem> + </varlistentry> + + + <varlistentry> + <term>DisplayInitDir</term> + <listitem> + <synopsis>DisplayInitDir=<etc>/gdm/Init</synopsis> + <para> + Directory containing the display init scripts. See the + ``The Script Directories'' section for more info. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>DisplayLastLogin</term> + <listitem> + <synopsis>DisplayLastLogin=true</synopsis> + <para> + If true then the last login information is printed to the user + before being prompted for password. While this gives away some + info on what users are on a system, it on the other hand should + give the user an idea of when they logged in and if it doesn't + seem kosher to them, they can just abort the login and contact + the sysadmin (avoids running malicious startup scripts). + This was added in version 2.5.90.0. + </para> + <para> + This is for making GDM conformant to CSC-STD-002-85, although + that is purely theoretical now. Someone should read that spec + and ensure that this actually conforms (in addition to other + places in GDM). See + <filename>http://www.radium.ncsc.mil/tpep/library/rainbow/CSC-STD-002-85.html</filename> + for more info. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>DoubleLoginWarning</term> + <listitem> + <synopsis>DoubleLoginWarning=true</synopsis> + <para> + If true, GDM will warn the user if they are already logged in + on another virtual terminal. On systems where GDM supports + checking the X virtual terminals, GDM will let the user switch + to the previous login virtual terminal instead of logging in. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>DynamicXServers</term> + <listitem> + <synopsis>DynamicXServers=false</synopsis> + <para> + If true, the GDM daemon will honor requests to manage + displays via the <filename>/tmp/.gdm_socket</filename> + socket connection. Displays can be created, started, + and deleted with the appropriate commands. The + <filename>gdmdynamic</filename> command is a convenient + method to send these messages. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>FailsafeXServer</term> + <listitem> + <synopsis>FailsafeXServer=</synopsis> + <para> + An X command line in case we can't start the normal X server. + should probably be some sort of a script that runs an + appropriate low resolution X server that will just work. + This is tried before the <filename>XKeepsCrashing</filename> + script is run. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>FirstVT</term> + <listitem> + <synopsis>FirstVT=7</synopsis> + <para> + On systems where GDM supports automatic VT (virtual terminal) + allocation, this is the first vt to try. Usually standard text + logins are run on the lower vts. See also + <filename>VTAllocation</filename>. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>FlexibleXServers</term> + <listitem> + <synopsis>FlexibleXServers=5</synopsis> + <para> + The maximum number of allowed flexible displays. These are + displays that can be run using the + <filename>/tmp/.gdm_socket</filename> socket connection. + This is used for both full flexible displays and for nested + displays (refer to the <filename>Xnest</filename> configuration + option). + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>FlexiReapDelayMinutes</term> + <listitem> + <synopsis>FlexiReapDelayMinutes=5</synopsis> + <para> + After how many minutes of inactivity at the login screen + should a flexi display be reaped. This is only in effect + before a user logs in. Also it does not affect nested displays + (refer to the <filename>Xnest</filename> configuration + option). To turn off this behavior set this value to 0. This + was added in version 2.5.90.0. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Greeter</term> + <listitem> + <synopsis>Greeter=<bin>/gdmlogin</synopsis> + <para> + Full path and name of the greeter executable followed by + optional arguments. This is the greeter used for all displays + except for the XDMCP remote displays. See also + <filename>RemoteGreeter</filename> + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Group</term> + <listitem> + <synopsis>Group=gdm</synopsis> + <para> + The group name under which <command>gdmlogin</command>, + <command>gdmgreeter</command>, + <command>gdmchooser</command> and the internal + failsafe GTK+ dialogs are run. Also see + <filename>User</filename>. This user will have access to all + the X authorization files, and perhaps to other internal GDM + data and it should not therefore be a user such as nobody, but + rather a dedicated user. The <filename>ServAuthDir</filename> + is owned by this group. The ownership and permissions of + <filename>ServAuthDir</filename> should be + <filename>root.gdm</filename> and 1770. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>GtkModulesList</term> + <listitem> + <synopsis>GtkModulesList=module-1:module-2:...</synopsis> + <para> + A colon separated list of Gtk+ modules that + <command>gdmgreeter</command> or <command>gdmlogin</command> + will be invoked with if <filename>AddGtkModules</filename> is + true. The format is the same as the standard Gtk+ module + interface. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>HaltCommand</term> + <listitem> + <synopsis>HaltCommand=<sbin>/shutdown -h now</synopsis> + <para> + Full path and arguments to command to be executed when user + selects "Shut Down" from the Actions menu. This can + be a ';' separated list of commands to try. If a value is + missing, the shut down command is not available. Note that the + default for this value is not empty, so to disable + "Shut Down" it must be + set to an empty value. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>KillInitClients</term> + <listitem> + <synopsis>KillInitClients=true</synopsis> + <para> + Determines whether GDM should kill X clients started by the + init scripts when the user logs in. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>LogDir</term> + <listitem> + <synopsis>LogDir=<var>/log/gdm</synopsis> + <para> + Directory containing the log files for the individual displays. + By default this is the same as the ServAuthDir. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>PreFetchProgram</term> + <listitem> + <synopsis>PreFetchProgram=command</synopsis> + <para> + Program to be run by the GDM greeter/login program when the + initial screen is displayed. The purpose is to provide a hook + where files which will be used after login can be preloaded to + speed performance for the user. The program will be called + once only, the first time a greeter is displayed. The + gdmprefetch command may be used. This utility will load any + libraries passed in on the command line, or if the argument + starts with a "@" character, it will process the file + assuming it is an ASCII file containing a list of libraries, + one per line, and load each library in the file. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>PostLoginScriptDir</term> + <listitem> + <synopsis>PostLoginScriptDir=<etc>/gdm/PostLogin</synopsis> + <para> + Directory containing the scripts run right after the user logs + in, but before any session setup is done. See the + ``The Script Directories'' section for more info. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>PostSessionScriptDir</term> + <listitem> + <synopsis>PostSessionScriptDir=<etc>/gdm/PostSession</synopsis> + <para> + Directory containing the scripts run after the user logs out. + See the ``The Script Directories'' section for more info. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>PreSessionScriptDir</term> + <listitem> + <synopsis>PreSessionScriptDir=<etc>/gdm/PreSession</synopsis> + <para> + Directory containing the scripts run before the user logs in. + See the ``The Script Directories'' section for more info. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>RBACSystemCommandKeys</term> + <listitem> + <synopsis>RBACSystemCommandKeys</synopsis> + <para> + Support RBAC (Role Based Access Control) for system commands + (Shutdown, Reboot, Suspend, etc.). This feature is only + functional if GDM is compiled with RBAC support. Specify the + RBAC key used to determine if the user has permission to use + the action via the QUERY_LOGOUT_ACTION, SET_LOGOUT_ACTION, and + SET_SAFE_LOGOUT_ACTION <command>gdmflexiserver</command> + commands. Valid actions are HALT, REBOOT, SUSPEND, and + CUSTOM_CMD. The greeter will only display the command if the + gdm user (<filename>User</filename> configuration key) has + RBAC permissions to use the action. RBAC keys for multiple + actions can be specified by separating them with semicolons. + The format for each is "Action:RBAC key". If an action is not + specified, it is assumed that all users have permission to use + this action. For example, a valid value for this + configuration option would be + "HALT:key.for.halt;REBOOT:key.for.reboot". Refer to + the related <filename>AllowLogoutActions</filename> and + <filename>SystemCommandsInMenu</filename> configuration + options. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term>RebootCommand</term> + <listitem> + <synopsis>RebootCommand=<sbin>/shutdown -r now</synopsis> + <para> + Full path and optional arguments to the command to be + executed when user selects Restart from the Actions menu. This + can be a ';' separated list of commands to try. If missing, + the restart command is not available. Note that the default + for this value is not empty so to disable restart you must set + this explicitly to an empty value. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>RemoteGreeter</term> + <listitem> + <synopsis>RemoteGreeter=<bin>/gdmlogin</synopsis> + <para> + Full path and name of the greeter executable followed by + optional arguments. This is used for all remote XDMCP + sessions. It is useful to have the less graphically demanding + greeter here if you use the Themed Greeter for your main + greeter. See also the <filename>Greeter</filename> key. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>RootPath</term> + <listitem> + <synopsis>RootPath=defaultpath (value set by configure)</synopsis> + <para> + Specifies the path which will be set in the root's + session and the {Init,PostLogin,PreSession,PostSession} scripts + executed by GDM. This value will be overridden with the value + from <filename>/etc/default/login</filename> if it + contains "SUROOT=<pathname>". If the + <filename>/etc/default/login</filename> file exists, but + contains no value for SUROOT, the value as defined in the GDM + configuration will be used. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>ServAuthDir</term> + <listitem> + <synopsis>ServAuthDir=<var>/gdm</synopsis> + <para> + Directory containing the X authentication files for the + individual displays. Should be owned by + <filename>root.gdm</filename> with permissions 1770, where + <filename>gdm</filename> is the GDM group as defined by the + <filename>Group</filename> option. That is should be owned by + root, with <filename>gdm</filename> group having full write + permissions and the directory should be sticky and others + should have no permission to the directory. This way the GDM + user can't remove files owned by root in that directory, while + still being able to write its own files there. GDM will + attempt to change permissions for you when it's first run if + the permissions are not the above. This directory is also used + for other private files that the daemon needs to store. Other + users should not have any way to get into this directory and + read/change it's contents. Anybody who can read this directory + can connect to any display on this computer. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>SessionDesktopDir</term> + <listitem> + <synopsis>SessionDesktopDir=<etc>/X11/sessions/:<etc>/dm/Sessions/:<share>/xsessions/</synopsis> + <para> + Directory containing the <filename>.desktop</filename> files + which are the available sessions on the system. Since 2.4.4.2 + this is treated like a PATH type variable and the first file + found is used. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>SoundProgram</term> + <listitem> + <synopsis>SoundProgram=<filename><bin>/play</filename> (or <filename><bin>/audioplay</filename> on Solaris)</synopsis> + <para> + Application to use when playing a sound. Currently used for + playing the login sound, see the + <filename>SoundOnLoginFile</filename> key. Supported since + 2.5.90.0. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>StandardXServer</term> + <listitem> + <synopsis>StandardXServer=/dir/to/X (value assigned by configuration file)</synopsis> + <para> + Full path and arguments to the standard X server command. + This is used when gdm cannot find any other definition, + and it's used as the default and failsafe fallback in a + number of places. This should be able to run some sort + of X server. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>SuspendCommand</term> + <listitem> + <synopsis>SuspendCommand=</synopsis> + <para> + Full path and arguments to command to be executed when + user selects Suspend from the Actions menu. If empty + there is no such menu item. Note that the default for this + value is not empty so to disable suspend you must set this + explicitly to an empty value. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>SystemCommandsInMenu</term> + <listitem> + <synopsis>SuspendCommand=HALT;REBOOT;SHUTDOWN;SUSPEND;CUSTOM_CMD</synopsis> + <para> + Specify which system commands are available in the greeter + menu. Valid values are HALT, REBOOT, SHUTDOWN, SUSPEND, and + CUSTOM_CMD and these should be separated by semicolons. This + can be useful if you want to disable some options in the menu, + but still have them available to authenticated users via the + SET_LOGOUT_ACTION or SET_SAFE_LOGOUT_ACTION + <command>gdmflexiserver</command> commands. For example, the + GNOME panel uses these commands to provide Shutdown, Reboot, + and Suspend in the application menu. Therefore if you turn + off these options in the greeter, these options can still be + available to users who have authenticated via the GNOME panel. + Refer to the related + <filename>AllowLogoutActions</filename> and + <filename>RBACSystemCommandKeys</filename> configuration + options. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>TimedLoginEnable</term> + <listitem> + <synopsis>TimedLoginEnable=false</synopsis> + <para> + If the user given in <filename>TimedLogin</filename> should be + logged in after a number of seconds (set with + <filename>TimedLoginDelay</filename>) of inactivity on the + login screen. This is useful for public access terminals or + perhaps even home use. If the user uses the keyboard or + browses the menus, the timeout will be reset to + <filename>TimedLoginDelay</filename> or 30 seconds, whichever + is higher. If the user does not enter a username but just + hits the ENTER key while the login program is requesting the + username, then GDM will assume the user wants to login + immediately as the timed user. Note that no password will be + asked for this user so you should be careful, although if using + PAM it can be configured to require password entry before + allowing login. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>TimedLogin</term> + <listitem> + <synopsis>TimedLogin=</synopsis> + <para> + This is the user that should be logged in after a specified + number of seconds of inactivity. This can never be + "root" and gdm will refuse to log in root this way. + The same features as for <filename>AutomaticLogin</filename> + are supported. The same control chars and piping to a + application are supported. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>TimedLoginDelay</term> + <listitem> + <synopsis>TimedLoginDelay=30</synopsis> + <para> + Delay in seconds before the <filename>TimedLogin</filename> + user will be logged in. It must be greater then or equal to 10. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>User</term> + <listitem> + <synopsis>User=gdm</synopsis> + <para> + The username under which <command>gdmlogin</command>, + <command>gdmgreeter</command>, + <command>gdmchooser</command> and the internal + failsafe GTK+ dialogs are run. Also see + <filename>Group</filename>. This user will have access to all + the X authorization files, and perhaps to other internal GDM + data and it should not therefore be a user such as nobody, but + rather a dedicated user. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>UserAuthDir</term> + <listitem> + <synopsis>UserAuthDir=</synopsis> + <para> + The directory where user's <filename>.Xauthority</filename> + file should be saved. When nothing is specified the user's + home directory is used. This is tilde expanded so you + can set it to things like: <filename>~/authdir/</filename>. + </para> + + <para> + If you do not use the tilde expansion, then the filename + created will be random, like in + <filename>UserAuthFBDir</filename>. This way many users can + have the same authentication directory. For example you might + want to set this to <filename>/tmp</filename> when user has the + home directory on NFS, since you really don't want cookie files + to go over the wire. The users should really have write + privileges to this directory, and this directory should really + be sticky and all that, just like the <filename>/tmp</filename> + directory. + </para> + + <para> + Normally if this is the user's home directory GDM will still + refuse to put cookies there if it thinks it is NFS (by testing + root-squashing). This can be changed by setting + <filename>NeverPlaceCookiesOnNFS</filename> in the + <filename>[security]</filename> section to false. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>UserAuthFBDir</term> + <listitem> + <synopsis>UserAuthFBDir=/tmp</synopsis> + <para> + If GDM fails to update the user's + <filename>.Xauthority</filename> file a fallback cookie is + created in this directory. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>UserAuthFile</term> + <listitem> + <synopsis>UserAuthFile=.Xauthority</synopsis> + <para> + Name of the file used for storing user cookies. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>VTAllocation</term> + <listitem> + <synopsis>VTAllocation=true</synopsis> + <para> + On systems where GDM supports automatic VT (virtual terminal) + allocation (currently Linux and FreeBSD only), you can have + GDM automatically append the vt argument to the X server + executable. This way races that come up from each X server + managing it's own vt allocation can be avoided. See also + <filename>FirstVT</filename>. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>XKeepsCrashing</term> + <listitem> + <synopsis>XKeepsCrashing=<etc>/gdm/XKeepsCrashing</synopsis> + <para> + A script to run in case X keeps crashing. This is for running + An X configuration or whatever else to make the X configuration + work. See the script that came with the distribution for an + example. The distributed <filename>XKeepsCrashing</filename> + script is tested on Red Hat, but may work elsewhere. Your + system integrator should make sure this script is up to date + for your particular system. + </para> + <para> + In case <filename>FailsafeXServer</filename> is setup, that + will be tried first. and this only used as a backup if even + that X server keeps crashing. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Xnest</term> + <listitem> + <synopsis>Xnest=<bin>/X11/Xephyr -audit 0</synopsis> + <para> + The full path and arguments to the nested X server command, + which can be Xephyr, Xnest, or similar program. This command + is used for starting nested displays allowing the user + to start new login screens in a nested window. Xephyr is + recommended since it works best and better supports modern + X server extensions. Therefore GDM will set the default + configuration to use Xephyr if available. If Xephyr is not + available, then Xnest will be used if it is available. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>XnestUnscaledFontPath</term> + <listitem> + <synopsis>XnestUnscaledFontPath=true</synopsis> + <para> + Set to true if the nested X server command program supports the + ":unscaled" suffix in the FontPath (passed to nested X server + command via the -fp argument). Some Xnest (e.g. Xsun Xnest) + programs do not, and it is necessary to set this to false for + such nested X server commands to work with GDM. Refer to the + <filename>Xnest</filename> configuration option. + </para> + </listitem> + </varlistentry> + </variablelist> + </sect3> + + <sect3 id="securitysection"> + <title>Security Options</title> + + <variablelist> + <title>[security]</title> + + <varlistentry> + <term>AllowRoot</term> + <listitem> + <synopsis>AllowRoot=true</synopsis> + <para> + Allow root (privileged user) to log in through GDM. Set this + to false if you want to disallow such logins. + </para> + <para> + On systems that support PAM, this parameter is not as useful + as you can use PAM to do the same thing, and in fact do even + more. However it is still followed, so you should probably + leave it true for PAM systems. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>AllowRemoteRoot</term> + <listitem> + <synopsis>AllowRemoteRoot=false</synopsis> + <para> + Allow root (privileged user) to log in remotely through GDM. + This value should be set to true to allow such logins. + Remote logins are any logins that come in through the XDMCP. + </para> + <para> + On systems that support PAM, this parameter is not as useful + since you can use PAM to do the same thing, and do even + more. + </para> + <para> + This value will be overridden and set to false if the + <filename>/etc/default/login</filename> file exists and + contains "CONSOLE=/dev/login", and set to true if the + <filename>/etc/default/login</filename> file exists and + contains any other value or no value for CONSOLE. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>AllowRemoteAutoLogin</term> + <listitem> + <synopsis>AllowRemoteAutoLogin=false</synopsis> + <para> + Allow the timed login to work remotely. That is, remote + connections through XDMCP will be allowed to log into the + "TimedLogin" user by letting the login window time + out, just like the local user on the first console. + </para> + <para> + Note that this can make a system quite insecure, and thus is + off by default. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>CheckDirOwner</term> + <listitem> + <synopsis>CheckDirOwner=true</synopsis> + <para> + By default GDM checks the ownership of the home directories + before writing to them, this prevents security issues in case + of bad setup. However in some instances home directories will + be owned by a different user and in this case it is necessary + to turn this option on. You will also most likely have to + turn the <filename>RelaxPermissions</filename> key to at least + value 1 since in such a scenario home directories are likely + to be group writable. Supported since 2.6.0.4. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>SupportAutomount</term> + <listitem> + <synopsis>SupportAutomount=false</synopsis> + <para> + By default GDM checks the ownership of the home directories + before writing to them, this prevents security issues in case + of bad setup. However, when home directories are managed by + automounter, they are often not mounted before they are + accessed. This option works around subtleties of Linux + automounter. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>DisallowTCP</term> + <listitem> + <synopsis>DisallowTCP=true</synopsis> + <para> + If true, then always append <filename>-nolisten tcp</filename> + to the command line + of local X servers, thus disallowing TCP connection. This is + useful if you do not care for allowing remote connections, + since the X protocol could really be potentially a security + hazard to leave open, even though no known security problems + exist. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>NeverPlaceCookiesOnNFS</term> + <listitem> + <synopsis>NeverPlaceCookiesOnNFS=true</synopsis> + <para> + Normally if this is true (which is by default), GDM will not + place cookies into the user's home directory if this directory + is on NFS. Well, GDM will consider any filesystem with + root-squashing an NFS filesystem. Sometimes however the remote + file system can have root squashing and be safe (perhaps by + using encryption). In this case set this to 'false'. Note + that this option appeared in version 2.4.4.4 and is ignored in + previous versions. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>PasswordRequired</term> + <listitem> + <synopsis>PasswordRequired=false</synopsis> + <para> + If true, this will cause PAM_DISALLOW_NULL_AUTHTOK to be + passed as a flag to pam_authenticate and pam_acct_mgmt, + disallowing NULL password. This setting will only take + effect if PAM is being used by GDM. This value will be + overridden with the value from + <filename>/etc/default/login</filename> if it contains + "PASSREQ=[YES|NO]". If the + <filename>/etc/default/login</filename> file exists, but + contains no value for PASSREQ, the value as defined in the GDM + configuration will be used. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>RelaxPermissions</term> + <listitem> + <synopsis>RelaxPermissions=0</synopsis> + <para> + By default GDM ignores files and directories writable to + other users than the owner. + </para> + + <para> + Changing the value of RelaxPermissions makes it possible to + alter this behavior: + </para> + + <para> + 0 - Paranoia option. Only accepts user owned files and + directories. + </para> + <para> + 1 - Allow group writable files and directories. + </para> + <para> + 2 - Allow world writable files and directories. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>RetryDelay</term> + <listitem> + <synopsis>RetryDelay=1</synopsis> + <para> + The number of seconds GDM should wait before reactivating the + entry field after a failed login. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>UserMaxFile</term> + <listitem> + <synopsis>UserMaxFile=65536</synopsis> + <para> + GDM will refuse to read/write files bigger than this number + (specified in bytes). + </para> + + <para> + In addition to the size check GDM is extremely picky about + accessing files in user directories. It will not follow + symlinks and can optionally refuse to read files and + directories writable by other than the owner. See the + <filename>RelaxPermissions</filename> option for more info. + </para> + </listitem> + </varlistentry> + </variablelist> + </sect3> + + <sect3 id="xdmcpsection"> + <title>XDCMP Support</title> + + <variablelist> + <title>[xdmcp]</title> + + <varlistentry> + <term>DisplaysPerHost</term> + <listitem> + <synopsis>DisplaysPerHost=1</synopsis> + <para> + To prevent attackers from filling up the pending queue, GDM + will only allow one connection for each remote computer. If + you want to provide display services to computers with more + than one screen, you should increase the + <filename>DisplaysPerHost</filename> value accordingly. + </para> + + <para> + Note that the number of connections from the local computer is + unlimited. Only remote connections are limited by this number. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Enable</term> + <listitem> + <synopsis>Enable=false</synopsis> + <para> + Setting this to true enables XDMCP support allowing remote + displays/X terminals to be managed by GDM. + </para> + + <para> + <filename>gdm</filename> listens for requests on UDP port 177. + See the Port option for more information. + </para> + + <para> + If GDM is compiled to support it, access from remote displays + can be controlled using the TCP Wrappers library. The service + name is <filename>gdm</filename> + </para> + + <para> + You should add +<screen> +gdm:.my.domain +</screen> + to your <filename><etc>/hosts.allow</filename>, depending + on your TCP Wrappers configuration. See the + <ulink type="help" url="man:hosts.allow">hosts.allow(5)</ulink> + man page for details. + </para> + + <para> + Please note that XDMCP is not a particularly secure protocol + and that it is a good idea to block UDP port 177 on your + firewall unless you really need it. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>EnableProxy</term> + <listitem> + <synopsis>EnableProxy=false</synopsis> + <para> + Setting this to true enables support for running XDMCP sessions + on a local proxy X server. This may improve the performance of + XDMCP sessions, especially on high latency networks, as many + X protocol operations can be completed without going over the + network. + </para> + <para> + Note, however, that this mode will significantly increase the + burden on the machine hosting the XDMCP sessions + </para> + <para> + See the <filename>FlexiProxy</filename> and + <filename>FlexiProxyDisconnect</filename> options for further + details on how to configure support for this feature. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>HonorIndirect</term> + <listitem> + <synopsis>HonorIndirect=true</synopsis> + <para> + Enables XDMCP INDIRECT choosing (i.e. remote execution of + <filename>gdmchooser</filename>) for X-terminals which don't + supply their own display browser. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>MaxPending</term> + <listitem> + <synopsis>MaxPending=4</synopsis> + <para> + To avoid denial of service attacks, GDM has fixed size queue + of pending connections. Only MaxPending displays can start at + the same time. + </para> + + <para> + Please note that this parameter does *not* limit the number of + remote displays which can be managed. It only limits the number + of displays initiating a connection simultaneously. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>MaxPendingIndirect</term> + <listitem> + <synopsis>MaxPendingIndirect=4</synopsis> + <para> + GDM will only provide <filename>MaxPendingIndirect</filename> + displays with host choosers simultaneously. If more queries + from different hosts come in, the oldest ones will be + forgotten. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>MaxSessions</term> + <listitem> + <synopsis>MaxSessions=16</synopsis> + <para> + Determines the maximum number of remote display connections + which will be managed simultaneously. I.e. the total number of + remote displays that can use your host. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>MaxWait</term> + <listitem> + <synopsis>MaxWait=30</synopsis> + <para> + When GDM is ready to manage a display an ACCEPT packet is sent + to it containing a unique session id which will be used in + future XDMCP conversations. + </para> + + <para> + GDM will then place the session id in the pending queue + waiting for the display to respond with a MANAGE request. + </para> + + <para> + If no response is received within MaxWait seconds, GDM will + declare the display dead and erase it from the pending queue + freeing up the slot for other displays. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>MaxWaitIndirect</term> + <listitem> + <synopsis>MaxWaitIndirect=30</synopsis> + <para> + The MaxWaitIndirect parameter determines the maximum number of + seconds between the time where a user chooses a host and the + subsequent indirect query where the user is connected to the + host. When the timeout is exceeded, the information about the + chosen host is forgotten and the indirect slot freed up for + other displays. The information may be forgotten earlier if + there are more hosts trying to send indirect queries then + <filename>MaxPendingIndirect</filename>. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Port</term> + <listitem> + <synopsis>Port=177</synopsis> + <para> + The UDP port number <filename>gdm</filename> should listen to + for XDMCP requests. Don't change this unless you know what + you are doing. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>PingIntervalSeconds</term> + <listitem> + <synopsis>PingIntervalSeconds=15</synopsis> + <para> + Interval in which to ping the X server in seconds. If the X + server doesn't return before the next time we ping it, the + connection is stopped and the session ended. This is a + combination of the XDM PingInterval and PingTimeout, but in + seconds. + </para> + + <para> + Note that GDM in the past used to have a + <filename>PingInterval</filename> configuration key which was + also in minutes. For most purposes you'd want this setting + to be lower then one minute however since in most cases where + XDMCP would be used (such as terminal labs), a lag of more + than 15 or so seconds would really mean that the terminal was + turned off or restarted and you would want to end the session. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>ProxyReconnect</term> + <listitem> + <synopsis>FlexiProxyReconnect=</synopsis> + <para> + Setting this option enables experimental support for session + migration with XDMCP sessions. This enables users to disconnect + from their session and later reconnect to that same session, + possibly from a different terminal. + </para> + <para> + In order to use this feature, you must have a nested X server + available which supports disconnecting from its parent X server + and reconnecting to another X server. Currently, the Distributed + Multihead X (DMX) server supports this feature to some extent + and other projects like NoMachine NX are busy implementing it. + </para> + <para> + This option should be set to the path of a command which will + handle reconnecting the XDMCP proxy to another backend display. + A sample implementation for use with DMX is supplied. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>ProxyXServer</term> + <listitem> + <synopsis>ProxyXServer=</synopsis> + <para> + The X server command line for a XDMCP proxy. Any nested X + server like Xnest, Xephyr or Xdmx should work fairly well. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Willing</term> + <listitem> + <synopsis>Willing=<etc>/gdm/Xwilling</synopsis> + <para> + When the machine sends a WILLING packet back after a QUERY it + sends a string that gives the current status of this server. + The default message is the system ID, but it is possible to + create a script that displays customized message. If this + script doesn't exist or this key is empty the default message + is sent. If this script succeeds and produces some output, + the first line of it's output is sent (and only the first + line). It runs at most once every 3 seconds to prevent + possible denial of service by flooding the machine with QUERY + packets. + </para> + </listitem> + </varlistentry> + </variablelist> + </sect3> + + <sect3 id="commonguioptions"> + <title>Common GUI Configuration Options</title> + + <variablelist> + <title>[gui]</title> + + <varlistentry> + <term>AllowGtkThemeChange</term> + <listitem> + <synopsis>AllowGtkThemeChange=true</synopsis> + <para> + If to allow changing the GTK+ (widget) theme from the greeter. + Currently this only affects the standard greeter as the + graphical greeter does not yet have this ability. + The theme will stay in effect on this display until changed + and will affect all the other windows that are put up by GDM. + Supported since 2.5.90.2. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>GtkRC</term> + <listitem> + <synopsis>GtkRC=</synopsis> + <para> + Path to a <filename>gtkrc</filename> to read when GDM puts up + a window. You should really now use the + <filename>GtkTheme</filename> key for just setting a theme. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>GtkTheme</term> + <listitem> + <synopsis>GtkTheme=Default</synopsis> + <para> + A name of an installed theme to use by default. It will be + used in the greeter, chooser and all other GUI windows put up + by GDM. Supported since 2.5.90.2. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>GtkThemesToAllow</term> + <listitem> + <synopsis>GtkThemesToAllow=all</synopsis> + <para> + Comma separated list of themes to allow. These must be the + names of the themes installed in the standard locations for + GTK+ themes. You can also specify 'all' to allow all installed + themes. This is related to the + <filename>AllowGtkThemeChange</filename> key. Supported since + 2.5.90.2. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>MaxIconWidth</term> + <listitem> + <synopsis>MaxIconWidth=128</synopsis> + <para> + Specifies the maximum icon width (in pixels) that the face + browser will display. Icons larger than this will be scaled. + This also affects icons in the XDMCP chooser. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>MaxIconHeight</term> + <listitem> + <synopsis>MaxIconHeight=128</synopsis> + <para> + Specifies the maximum icon height (in pixels) that the face + browser will display. Icons larger than this will be scaled. + This also affects icons in the XDMCP chooser. + </para> + </listitem> + </varlistentry> + </variablelist> + </sect3> + + <sect3 id="greetersection"> + <title>Greeter Configuration</title> + + <variablelist> + <title>[greeter]</title> + + <varlistentry> + <term>BackgroundColor</term> + <listitem> + <synopsis>BackgroundColor=#76848F</synopsis> + <para> + If the BackgroundType is 2, use this color in the background + of the greeter. Also use it as the back of transparent images + set on the background and if the BackgroundRemoteOnlyColor + is set and this is a remote display. + This only affects the GTK+ Greeter. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>BackgroundProgramInitialDelay</term> + <listitem> + <synopsis>BackgroundProgramInitialDelay=30</synopsis> + <para> + The background application will be started after at least that + many seconds of inactivity. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>RestartBackgroundProgram</term> + <listitem> + <synopsis>RestartBackgroundProgram=true</synopsis> + <para> + If set the background application will be restarted when it has + exited, after the delay described below has elapsed. This + option can be useful when you wish to run a screen saver + application when no user is using the computer. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>BackgroundProgramRestartDelay</term> + <listitem> + <synopsis>BackgroundProgramRestartDelay=30</synopsis> + <para> + The background application will be restarted after at least that + many seconds of inactivity. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>BackgroundImage</term> + <listitem> + <synopsis>BackgroundImage=somefile.png</synopsis> + <para> + If the BackgroundType is 1, then display this file as the + background in the greeter. This only affects the GTK+ + Greeter. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>BackgroundProgram</term> + <listitem> + <synopsis>BackgroundProgram=<bin>/xeyes</synopsis> + <para> + If set this command will be run in the background while + the login window is being displayed. Note that not all + applications will run this way, since GDM does not usually have + a home directory. You could set up home directory for the + GDM user if you wish to run applications which require it. + This only affects the GTK+ Greeter. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>BackgroundRemoteOnlyColor</term> + <listitem> + <synopsis>BackgroundRemoteOnlyColor=true</synopsis> + <para> + On remote displays only set the color background. This is to + make network load lighter. The + <filename>BackgroundProgram</filename> is also not run. This + only affects the GTK+ Greeter. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>BackgroundScaleToFit</term> + <listitem> + <synopsis>BackgroundScaleToFit=true</synopsis> + <para> + Scale background image to fit the screen. This only affects + the GTK+ Greeter. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>BackgroundType</term> + <listitem> + <synopsis>BackgroundType=2</synopsis> + <para> + The type of background to set. 0 is none, 1 is image and color, + 2 is color and 3 is image. This only affects the GTK+ Greeter. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Browser</term> + <listitem> + <synopsis>Browser=true</synopsis> + <para> + Set to true to enable the face browser. See the + ``The GTK+ Greeter'' section for more information on the + face browser. This option only works for the GTK+ Greeter. + For the Themed Greeter, the face browser is enabled by + choosing a theme which includes a face browser + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>ChooserButton</term> + <listitem> + <synopsis>ChooserButton=true</synopsis> + <para> + If true, add a chooser button to the Actions menu that will + restart the current X server with a chooser. XDMCP does not + need to be enabled on the local computer for this to work. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>ConfigAvailable</term> + <listitem> + <synopsis>ConfigAvailable=false</synopsis> + <para> + If true, allows the configurator to be run from the greeter. + Note that the user will need to type in the root password + before the configurator will be started. This is set to + false by default for additional security. See the + <filename>Configurator</filename> option in the daemon + section. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>DefaultFace</term> + <listitem> + <synopsis>DefaultFace=<share>/pixmaps/nophoto.png</synopsis> + <para> + If a user has no defined face image, GDM will use the + "stock_person" icon defined in the current GTK+ + theme. If no such image is defined, the image specified by + <filename>DefaultFace</filename> will be used. The image must + be in a gdk-pixbuf supported format and the file must be + readable to the GDM user. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Include</term> + <listitem> + <synopsis>Include=</synopsis> + <para> + Comma separated list of users to be included in the face + browser and in the <command>gdmsetup</command> selection list + for Automatic/Timed login. + See also <filename>Exclude</filename>, + <filename>IncludeAll</filename>, and + <filename>MinimalUID</filename>. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Exclude</term> + <listitem> + <synopsis>Exclude=bin,daemon,adm,lp,sync,shutdown,halt,mail,...</synopsis> + <para> + Comma separated list of users to be excluded from the face + browser and from the <command>gdmsetup</command> selection list + for Automatic/Timed login. Excluded users will still be able to + log in, but will have to type their username. + See also <filename>Include</filename>, + <filename>IncludeAll</filename>, and + <filename>MinimalUID</filename>. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>IncludeAll</term> + <listitem> + <synopsis>IncludeAll=false</synopsis> + <para> + By default, an empty include list means display no users. + By setting IncludeAll to true, the password file will be + scanned and all users will be displayed aside from users + excluded via the Exclude setting and user ID's less than + MinimalUID. Scanning the password file can be slow on + systems with large numbers of users and this feature should + not be used in such environments. + See also <filename>Include</filename>, + <filename>Exclude</filename>, and + <filename>MinimalUID</filename>. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>GlobalFaceDir</term> + <listitem> + <synopsis>GlobalFaceDir=<share>/pixmaps/faces/</synopsis> + <para> + Systemwide directory for face files. The sysadmin can place + icons for users here without touching their homedirs. Faces are + named after their users' logins. + </para> + + <para> + I.e. <filename><GlobalFaceDir>/johndoe</filename> would + contain the face icon for the user ``johndoe''. No image format + extension should be specified. + </para> + + <para> + The face images must be stored in gdk-pixbuf supported formats + and they must be readable for the GDM user. + </para> + + <para> + A user's own icon file will always take precedence over the + sysadmin provided one. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>GraphicalTheme</term> + <listitem> + <synopsis>GraphicalTheme=circles</synopsis> + <para> + The graphical theme that the Themed Greeter should use. it + should refer to a directory in the theme directory set by + <filename>GraphicalThemeDir</filename>. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>GraphicalThemes</term> + <listitem> + <synopsis>GraphicalThemes=circles</synopsis> + <para> + The graphical themes that the Themed Greeter should use is the + Mode is set on Random Themes. This is a "/:" + delimited list. It should refer to a directory in the theme + directory set by <filename>GraphicalThemeDir</filename>. This + is only used if <filename>GraphicalThemeRand</filename> is set + to true. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>GraphicalThemeRand</term> + <listitem> + <synopsis>GraphicalThemeRand=false</synopsis> + <para> + Whether the graphical greeter will use Only One Theme or Random + Theme mode. Only One Theme mode uses themes listed by + <filename>GraphicalTheme</filename>, Random Themes mode uses + themes listed by <filename>GraphicalThemes</filename>. A value + of false sets greeter to use Only One Theme mode, a value of + true sets the greeter to use Random Theme mode. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>GraphicalThemeDir</term> + <listitem> + <synopsis>GraphicalThemeDir=<share>/gdm/themes/</synopsis> + <para> + The directory where themes for the Themed Greeter are + installed. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>GraphicalThemedColor</term> + <listitem> + <synopsis>GraphicalThemedColor=#76848F</synopsis> + <para> + Use this color in the background of the Themed Greeter. + This only affects the Themed Greeter. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>InfoMsgFile</term> + <listitem> + <synopsis>InfoMsgFile=/path/to/infofile</synopsis> + <para> + If present and /path/to/infofile specifies an existing and + readable text file (e.g. <etc>/infomsg.txt) the contents + of the file will be displayed in a modal dialog box before the + user is allowed to login. This works both with the standard + and the themable greeters. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>InfoMsgFont</term> + <listitem> + <synopsis>InfoMsgFont=fontspec</synopsis> + <para> + If present and InfoMsgFile (see above) is used, this specifies + the font to use when displaying the contents of the InfoMsgFile + text file. For example fontspec could be Sans 24 to get a + sans serif font of size 24 points. + This works both with the standard and the themable greeters. + </para> + </listitem> + </varlistentry> + + + <varlistentry> + <term>LocaleFile</term> + <listitem> + <synopsis>LocaleFile=<etc>/gdm/locale.alias</synopsis> + <para> + File in format similar to the GNU locale format with entries + for all supported languages on the system. The format is + described above or in a comment inside that file. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>LockPosition</term> + <listitem> + <synopsis>LockPosition=true</synopsis> + <para> + If true the position of the login window of the GTK+ + Greeter cannot be changed even if the title bar is turned on. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Logo</term> + <listitem> + <synopsis>Logo=<share>/pixmaps/gnome-logo-large.png</synopsis> + <para> + Image file to display in the logo box. The file must be + in a gdk-pixbuf supported format and it must be readable by + the GDM user. If no file is specified the logo feature + is disabled. + This only affects the GTK+ Greeter. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>ChooserButtonLogo</term> + <listitem> + <synopsis>ChooserButtonLogo=<share>/pixmaps/gnome-logo-large.png</synopsis> + <para> + Image file to display in the file chooser button in + <command>gdmsetup</command>. This key is modified by + <command>gdmsetup</command> and should not be manually + modified by the user. This only affects the Login Window + Preferences (<command>gdmsetup</command>). + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>MinimalUID</term> + <listitem> + <synopsis>MinimalUID=100</synopsis> + <para> + The minimal UID that GDM should consider a user. All + users with a lower UID will be excluded from the face browser. + See also <filename>Include</filename>, + <filename>Exclude</filename>, and + <filename>IncludeAll</filename>. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>PositionX</term> + <listitem> + <synopsis>PositionX=200</synopsis> + <para> + The horizontal position of the login window of the GTK+ + Greeter. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>PositionY</term> + <listitem> + <synopsis>PositionY=100</synopsis> + <para> + The vertical position of the login window of the GTK+ + Greeter. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Quiver</term> + <listitem> + <synopsis>Quiver=true</synopsis> + <para> + Controls whether <command>gdmlogin</command> should + shake the display when an incorrect username/password is + entered. + This only affects the GTK+ Greeter. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>DefaultRemoteWelcome</term> + <listitem> + <synopsis>DefaultRemoteWelcome=true</synopsis> + <para> + If set to true, the value "Welcome to %n" is used for + the <filename>RemoteWelcome</filename>. This value is + translated into the appropriate language for the user. If set + to false, the <filename>RemoteWelcome</filename> setting is + used. This string can use the same special character sequences + as explained in the "Text Node" section of the + "Themed Greeter" chapter. This explains the meaning + of "%n". + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>RemoteWelcome</term> + <listitem> + <synopsis>RemoteWelcome=Welcome to %n</synopsis> + <para> + Controls which text to display next to the logo image in the + greeter for remote XDMCP sessions. The same expansion is + done here as in the <filename>Welcome</filename> string. + This string can use the same special character sequences as + explained in the "Text Node" section of the + "Themed Greeter" chapter. + chapter. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>RunBackgroundProgramAlways</term> + <listitem> + <synopsis>RunBackgroundProgramAlways=false</synopsis> + <para> + If this is true then the background application is run always, + otherwise it is only run when the + <filename>BackgroundType</filename> is 0 (None) + This only affects the GTK+ Greeter. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>SetPosition</term> + <listitem> + <synopsis>SetPosition=true</synopsis> + <para> + If true the position of the login window of the GTK+ Greeter + is determined by <filename>PositionX</filename> + / <filename>PositionY</filename>. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>ShowGnomeFailsafeSession</term> + <listitem> + <synopsis>ShowGnomeFailsafeSession=true</synopsis> + <para> + Should the greeter show the Gnome Failsafe session in th + sessions list. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>ShowLastSession</term> + <listitem> + <synopsis>ShowLastSession=true</synopsis> + <para> + Should the greeter show the 'Last' session in the session list. + If this is off, then GDM is in the so called 'switchdesk' mode + which for example Red Hat uses. That is, the users can't pick + the last session and will just then get the default session + (see <filename>DefaultSession</filename>) unless then pick + something else for this session only. So if this is off, this + really circumvents saving of the last session. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>ShowXtermFailsafeSession</term> + <listitem> + <synopsis>ShowXtermFailsafeSession=true</synopsis> + <para> + Should the greeter show the Xterm Failsafe session in the + sessions list. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>SoundOnLogin</term> + <listitem> + <synopsis>SoundOnLogin=true</synopsis> + <para> + If true, the greeter will play a sound or beep when it is + ready for a login. See also the + <filename>SoundOnLoginFile</filename> key. + Supported since 2.5.90.0. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>SoundOnLoginSuccess</term> + <listitem> + <synopsis>SoundOnLoginSuccess=true</synopsis> + <para> + If true, the greeter will play a sound after a successful login + attempt. See also the + <filename>SoundOnLoginSuccessFile</filename> key. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>SoundOnLoginFailure</term> + <listitem> + <synopsis>SoundOnLoginFailure=true</synopsis> + <para> + If true, the greeter will play a sound after a failed login + attempt. See also the + <filename>SoundOnLoginFailureFile</filename> key. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>SoundOnLoginFile</term> + <listitem> + <synopsis>SoundOnLoginFile=/path/to/sound.wav</synopsis> + <para> + The file that will be played using the specified sound + application (by default that is + <filename>/usr/bin/play</filename>) instead of a beep when the + greeter is ready for a login. See also the + <filename>SoundOnLogin</filename> key and the + <filename>SoundProgram</filename> key. Supported since + 2.5.90.0. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>SoundOnLoginSuccessFile</term> + <listitem> + <synopsis>SoundOnLoginSuccessFile=/path/to/sound.wav</synopsis> + <para> + The file that will be played using the specified sound + application (by default that is + <filename>/usr/bin/play</filename>) after a successful login + attempt. See also the <filename>SoundOnLoginSuccess</filename> + key and the <filename>SoundProgram</filename> key. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>SoundOnLoginFailureFile</term> + <listitem> + <synopsis>SoundOnLoginFailureFile=/path/to/sound.wav</synopsis> + <para> + The file that will be played using the specified sound + application (by default that is + <filename>/usr/bin/play</filename>) after a failed login + attempt. See also the <filename>SoundOnLoginFailure</filename> + key and the <filename>SoundProgram</filename> key. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>SystemMenu</term> + <listitem> + <synopsis>SystemMenu=true</synopsis> + <para> + Turns the Actions menu (which used to be called System menu) on + or off. If this is off then one of the actions will be + available anywhere. These actions include Shutdown, Restart, + Configure, XDMCP chooser and such. All of those can however + be turned off individually. Shutdown, Restart and Suspend can + be turned off by just setting the corresponding keys to empty. + Note that the actions menu is only shown on local logins as it + would not be safe or even desirable on remote logins, so you + don't have to worry about remote users having any sort of + console privileges. + </para> + + <para> + Note that if this is off none of the actions will be available + even if a theme for a graphical greeter mistakenly shows them. + Also note that sometimes a graphical theme may not show all + the available actions as buttons and you may have to press + F10 to see the menu. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>TitleBar</term> + <listitem> + <synopsis>TitleBar=true</synopsis> + <para> + Display the title bar in the greeter. + This only affects the GTK+ Greeter. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Use24Clock</term> + <listitem> + <synopsis>Use24Clock=auto</synopsis> + <para> + Select the use of 24 hour clock. Some locales do not + support 12 hour format (like Finnish, that is + <filename>fi_FI</filename>), and in those locales this + setting has no effect at all. + </para> + <para> + Possible values are "auto" (default), + "true", and "false". If this is set to + "auto" or left empty, then time format is chosen from + locale settings. Locale settings are based on the language in + use, thus it is changed by setting environment variables + LANGUAGE (GNU extension), LANG, LC_MESSAGES or LC_ALL in the + GDM's runtime environment. Priorities between the mentioned + environment variables can be found from your system's + C library manual. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>UseCirclesInEntry</term> + <listitem> + <synopsis>UseCirclesInEntry=false</synopsis> + <para> + Use circles instead of asterisks in the password entry. + This may not work with all fonts however. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>UseInvisibleInEntry</term> + <listitem> + <synopsis>UseInvisibleInEntry=false</synopsis> + <para> + Do not show any visual feedback is the password entry. + This is the standard in console and xdm. Settings this + option discards the <filename>UseCirclesInEntry</filename> + option. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>DefaultWelcome</term> + <listitem> + <synopsis>DefaultWelcome=true</synopsis> + <para> + If set to true, the value "Welcome" is used for the + <filename>Welcome</filename>. This value is translated + into the appropriate language for the user. If set to + false, the <filename>Welcome</filename> setting is used. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Welcome</term> + <listitem> + <synopsis>Welcome=Welcome</synopsis> + <para> + Controls which text to display next to the logo image in the + standard greeter. The following control chars are supported: + </para> + + <para> + %% — the `%' character + </para> + + <para> + %d — display's hostname + </para> + + <para> + %h — Fully qualified hostname + </para> + + <para> + %m — machine (processor type) + </para> + + <para> + %n — Nodename (i.e. hostname without .domain) + </para> + + <para> + %r — release (OS version) + </para> + + <para> + %s — sysname (i.e. OS) + </para> + + <para> + This string is only used for local logins. For remote XDMCP + logins we use <filename>RemoteWelcome</filename>. + </para> + + <para> + In the Themed Greeter the location of this text depends on + the theme. Unless the theme uses the stock welcome string + somewhere this string will not be displayed at all. + </para> + + </listitem> + </varlistentry> + + <varlistentry> + <term>XineramaScreen</term> + <listitem> + <synopsis>XineramaScreen=0</synopsis> + <para> + If the Xinerama extension is active the login window will be + centered on this physical screen (use 0 for the first screen, + 1 for the second...). + </para> + </listitem> + </varlistentry> + </variablelist> + </sect3> + + <sect3 id="choosersection"> + <title>XDCMP Chooser Options</title> + + <variablelist> + <title>[chooser]</title> + + <varlistentry> + <term>AllowAdd</term> + <listitem> + <synopsis>AllowAdd=true</synopsis> + <para> + If true, allow the user to add arbitrary hosts to the chooser. + This way the user could connect to any host that responds to + XDMCP queries from the chooser. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Broadcast</term> + <listitem> + <synopsis>Broadcast=true</synopsis> + <para> + If true, the chooser will broadcast a query to the local + network and collect responses. This way the chooser will + always show all available managers on the network. If you + need to add some hosts not local to this network, or if you + don't want to use a broadcast, you can list them explicitly + in the <filename>Hosts</filename> key. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Multicast</term> + <listitem> + <synopsis>Multicast=true</synopsis> + <para> + If true and IPv6 is enabled, the chooser will send a multicast + query to the local network and collect responses from the hosts + who have joined multicast group. If you don't want to send a + multicast, you can specify IPv6 address in the <filename>Hosts + </filename> key. The host will respond if it is listening to + XDMCP requests and IPv6 is enabled there. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>MulticastAddr</term> + <listitem> + <synopsis>MulticastAddr=ff02::1</synopsis> + <para> + This is the Link-local Multicast address and is hardcoded here. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>DefaultHostImage</term> + <listitem> + <synopsis>DefaultHostImage=<share>/pixmaps/nohost.png</synopsis> + <para> + File name for the default host icon. This image will be + displayed if no icon is specified for a given host. The + file must be in a gdk-pixbuf supported format and it must be + readable for the GDM user. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>HostImageDir</term> + <listitem> + <synopsis>HostImageDir=<share>/hosts</synopsis> + <para> + Repository for host icon files. The sysadmin can place icons + for remote hosts here and they will appear in + <filename>gdmchooser</filename>. + </para> + + <para> + The file name must match the fully qualified name (FQDN) for + the host. The icons must be stored in gdk-pixbuf supported + formats and they must be readable to the GDM user. + </para> + + </listitem> + </varlistentry> + + <varlistentry> + <term>Hosts</term> + <listitem> + <synopsis>Hosts=host1,host2</synopsis> + <para> + The hosts which should be listed in the chooser. The chooser + will only list them if they respond. This is done in addition + to broadcast (if <filename>Broadcast</filename> is set), so you + need not list hosts on the local network. This is useful if + your networking setup doesn't allow all hosts to be reachable + by a broadcast packet. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>ScanTime</term> + <listitem> + <synopsis>ScanTime=4</synopsis> + <para> + Specifies how many seconds the chooser should wait for + replies to its BROADCAST_QUERY. Really this is only the time + in which we expect a reply. We will still add hosts to the + list even if they reply after this time. + </para> + </listitem> + </varlistentry> + </variablelist> + </sect3> + + <sect3 id="debugsection"> + <title>Debug Configuration</title> + + <variablelist> + <title>[debug]</title> + + <varlistentry> + <term>Enable</term> + <listitem> + <synopsis>Enable=false</synopsis> + <para> + Setting to true sends debug ouput to the syslog. This can be + useful for tracking down problems with GDM. This output + tends to be verbose so should not be turned on for general + use. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>Gestures</term> + <listitem> + <synopsis>Gestures=false</synopsis> + <para> + Setting to true sends debug ouput concerning the accessibility + gesture listeners to the syslog. This can be useful for + tracking down problems with them not working properly. This + output tends to be verbose so should not be turned on for + general use. + </para> + </listitem> + </varlistentry> + </variablelist> + </sect3> + + <sect3 id="customcmdsection"> + <title>Custom Commands</title> + + <para> + You can create up to 10 different commands. Gaps between command + numbers are allowed and their relative positioning within the + section and with respect to each other is not important as long as + they conform to the permitted range of [0-9]. + + </para> + + <variablelist> + <title>[customcommand]</title> + + <varlistentry> + <term>CustomCommand[0-9]</term> + <listitem> + <synopsis>CustomCommand[0-9]=</synopsis> + <para> + Full path and arguments to command to be executed when user + selects <filename>n-th</filename> "Custom Command" + from the Actions menu. This can be a ';' separated list of + commands to try. If the value is empty or missing, then the + custom command is not available. By default this value is not + enabled, so to enable "Custom Command" it must be + set to a nonempty value. [0-9] represents the + <filename>CustomCommand</filename> suffix and can be an + integer between 0 and 9. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>CustomCommandIsPersistent[0-9]</term> + <listitem> + <synopsis>CustomCommandIsPersistent[0-9]=</synopsis> + <para> + Specifies if <filename>n-th</filename> "Custom + Command" will appear outside the login manager, for + example on the desktop through the Log Out/Shut Down dialogs. + If not specified the default value is "false". This + option is only valid if corresponding + <filename>CustomCommand</filename> is defined. [0-9] represents + <filename>CustomCommand</filename> suffix and can be an integer + between 0 and 9. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>CustomCommandLabel[0-9]</term> + <listitem> + <synopsis>CustomCommandLabel[0-9]=</synopsis> + <para> + Specifies the stock label that will be displayed on the + <filename>n-th</filename> "Custom Command" + buttons and menu items. If not specified the default value is + "Custom_[0-9]". This option is only valid if + corresponding <filename>CustomCommand</filename> is defined. + [0-9] represents <filename>CustomCommand</filename> suffix + and can be an integer between 0 and 9. This option can't contain + any semicolon characters (i.e. ";"). + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>CustomCommandLRLabel[0-9]</term> + <listitem> + <synopsis>CustomCommandLRLabel[0-9]=</synopsis> + <para> + Specifies the stock label that will be displayed on the + <filename>n-th</filename> "Custom Command" + list items and radio buttons. If not specified the default + value is "Execute custom command _[0-9]". This + option is only valid if corresponding + <filename>CustomCommand</filename> is defined. [0-9] + represents <filename>CustomCommand</filename> suffix and + can be an integer between 0 and 9. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>CustomCommandNoRestart[0-9]</term> + <listitem> + <synopsis>CustomCommandNoRestart[0-9]=</synopsis> + <para> + Specifies if gdm will be stopped/restarted once + <filename>n-th</filename> "Custom Command" + has been executed. If not specified the default value is + "false". This option is only valid if corresponding + <filename>CustomCommand</filename> is defined. [0-9] + represents <filename>CustomCommand</filename> suffix and + can be an integer between 0 and 9. In addition when + corresponding <filename>CustomCommandIsPersistent</filename> + is set to true, setting CustomCommandNoRestart to false will + place corresponding <filename>CustomCommand</filename> in the + Shut Down dialog set of actions, setting it to true will place + corresponding + <filename>CustomCommand</filename> in the Log Out dialog set of + actions. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>CustomCommandText[0-9]</term> + <listitem> + <synopsis>CustomCommandText[0-9]=</synopsis> + <para> + Specifies the message that will be displayed on the warning + dialog box once <filename>n-th</filename> + "Custom Command" button/menu item/radio button/list + item has been activated. If not specified the default value is + "Are you sure?". This option is only valid if + corresponding <filename>CustomCommand</filename> is defined. + [0-9] represents <filename>CustomCommand</filename> suffix and + can be an integer between 0 and 9. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>CustomCommandTooltip[0-9]</term> + <listitem> + <synopsis>CustomCommandTooltip[0-9]=</synopsis> + <para> + Specifies the message that will be displayed on tooltips for + <filename>n-th</filename> "Custom Command" + entries. If not specified the default value is "Execute + custom command [0-9]". This option is only valid if + corresponding <filename>CustomCommand</filename> is defined. + [0-9] represents <filename>CustomCommand</filename> suffix and + can be an integer between 0 and 9. + </para> + </listitem> + </varlistentry> + </variablelist> + </sect3> + + <sect3 id="serverdefs"> + <title>X Server Definitions</title> + + <para> + To set up X servers, you need to provide GDM with information about + the installed X servers. You can have as many different definitions + as you wish, each identified with a unique name. The name + <filename>Standard</filename> is required. If you do not specify + this server, GDM will assume default values for a 'Standard' server + and the path given by <filename>daemon/StandardXServer</filename>. + <filename>Standard</filename> is used as the default, + in situations when no other server has been defined. + </para> + + <para> + Servers are defined by sections named <filename>server-</filename> + followed by the identifier of this server. This should be a simple + ASCII string with no spaces. The GUI configuration program allows + users to edit the servers defined in the GDM configuration files + but currently does not allow adding or deleting entries. Like normal + configuration options, <filename>server-</filename> sections in the + GDM Custom Configuration File override values in the GDM System + Defaults Configuration File. In other words, if a + <filename>server-Standard</filename> section is defined in the GDM + Custom Configuration File, then that will be used and the section in + the GDM System Defaults Configuration File will be ignored. + </para> + + <variablelist> + <title>[server-Standard]</title> + + <varlistentry> + <term>name</term> + <listitem> + <synopsis>name=Standard server</synopsis> + <para> + The name that will be displayed to the user. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>command</term> + <listitem> + <synopsis>command=/path/to/X</synopsis> + <para> + The command to execute, with full path to the binary of the X + server, and any extra arguments needed. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>flexible</term> + <listitem> + <synopsis>flexible=true</synopsis> + <para> + Indicates if this server is available as a choice when a + user wishes to run a flexible, on demand server. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>handled</term> + <listitem> + <synopsis>handled=true</synopsis> + <para> + Indicates that GDM should run the login window on this server + and allow a user to log in. If set to false, then GDM will + just run this server and wait for it to terminate. This can be + useful to run an X terminal using GDM. When this is done you + should normally also add <filename>-terminate</filename> to the + command line of the server to make the server terminate after + each session. Otherwise the control of the slave will never + come back to GDM and, for example, soft restarts won't work. + This is because GDM assumes there is a login in progress for + the entire time this server is active. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>chooser</term> + <listitem> + <synopsis>chooser=false</synopsis> + <para> + Indicates that GDM should instead of a login window run a + chooser on this window and allow the user to choose which + server to log into. + </para> + </listitem> + </varlistentry> + </variablelist> + </sect3> + + <sect3 id="localservers"> + <title>Local Static X Display Configuration</title> + + <para> + The static display configuration specifies what displays should be + always managed by GDM. GDM will restart the X server on the display + if it dies, for example. There may be as many static displays that + are managed as you wish, although typically each display is + associated with a real display. For example, if a machine has two + displays (say display ":0" and display ":1"), + then this section can be used to specify that a separate login + screen be managed for each screen. Each key in the + <filename>[servers]</filename> section corresponds to the display + number to be managed. Normally there is only one key, which is the + key <filename>0</filename>, which corresponds to the display + <filename>:0</filename>. + </para> + + <para> + The GUI configuration program allows users to edit the static display + configuration defined in the GDM configuration files and allows the + user to add or delete entries. Like normal configuration options, + the <filename>[servers]</filename> section in the GDM Custom + Configuration File overrides values in the GDM System Defaults + Configuration File. + </para> + + <variablelist> + <title>[servers]</title> + + <varlistentry> + <term><display number></term> + <listitem> + <synopsis>0=Standard</synopsis> + <para> + Control section for local displays. Each line indicates + the local display number and the command that needs to + be run to start the X server(s). + </para> + + <para> + The command can either be a path to an X executable, or a name + of one of the server definitions. This can be followed by some + arguments that should be passed to the X server when executed. + The gdm daemon doesn't enforce the numbers to be in order or + for them to be "packed". They keyword + "inactive" can be used instead of a command to + specify that the display should be not managed. This can be + used in the GDM Custom Configuration File to turn off a + display that is defined in the GDM System Defaults + Configuration File. + </para> + + <para> + GDM will splice "<filename>-auth + <ServAuthDir>/:n.Xauth :n</filename>", where n is + the display number. Inside the command line before all + other arguments before running the X server. + </para> + + <para> + On some systems it is necessary for GDM to know on which + virtual consoles to run the X server. In this case, + (if running XFree86) add "vt7" to the command line, + for example, to run on virtual console 7. However on Linux and + FreeBSD this is normally done automatically if the + <filename>VTAllocation</filename> key is set. + </para> + + <para> + Normally you do not need to add a + <filename>-nolisten tcp</filename> flag as this is added + automatically for local X servers when the + <filename>DisallowTCP</filename> option is set. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>priority</term> + <listitem> + <synopsis>priority=0</synopsis> + <para> + Indicates that the X server should be started at a + different process priority. Values can be any integer + value accepted by the setpriority C library function + (normally between -20 and 20) with 0 being the default. + For highly interactive applications, -5 yields good + responsiveness. The default value is 0 and the + setpriority function is not called if the value is 0. + </para> + </listitem> + </varlistentry> + </variablelist> + </sect3> + </sect2> + + <sect2 id="userconfig"> + <title>Per User Configuration</title> + + <para> + There are some per user configuration settings that control how GDM + behaves. GDM is picky about the file ownership and permissions of + the user files it will access, and will ignore files if they are not + owned by the user or files that have group/world write permission. + It will also ignore the user if the user's $HOME directory is not + owned by the user or if the user's $HOME directory has group/world + write permission. files must also be smaller than the + <filename>UserMaxFile</filename> value as defined in the GDM + configuration. If it seems that GDM is not properly accessing + user configuration settings, the problem is most likely + caused by one of these checks failing. + </para> + + <para> + First there is the <filename>~/.dmrc</filename> file. In + theory this file should be shared between GDM and KDM, so users only + have to configure things once. This is a standard + <filename>.ini</filename> style configuration file. It has one section + called <filename>[Desktop]</filename> which has two keys: + <filename>Session</filename> and <filename>Language</filename>. + </para> + + <para> + The <filename>Session</filename> key specifies the basename of the + session <filename>.desktop</filename> file that the user wishes to + normally use (without the <filename>.desktop</filename> extension, in + other words). The <filename>Language</filename> key specifies the + language that the user wishes to use by default. If either of these + keys is missing, the system default is used. The file would normally + look as follows: + </para> + +<screen> +[Desktop] +Session=gnome +Language=cs_CZ.UTF-8 +</screen> + + <para> + Normally GDM will write this file when the user logs in for the first + time, and rewrite it if the user chooses to change their default values + on a subsequent login. + </para> + + <para> + If the GDM Face Browser is turned on, then the file + <filename>$HOME/.face</filename> is accessed. This file should be a + standard image that GTK+ can read, such as PNG or JPEG. It also must + be smaller than the <filename>MaxIconWidth</filename> and + <filename>MaxIconHeight</filename> values defined in the GDM + configuration or it will be ignored. Users can run the + <command>gdmphotosetup</command> program to specify a face image + and it will copy the file to the <filename>$HOME/.face</filename> + location and scale it so its longest dimension is not larger than the + <filename>MaxIconWidth</filename> or <filename>MaxIconHeight</filename> + values. <command>gdmphotosetup</command> takes care to not change + the aspect ratio of the image. + </para> + + <para> + Face images can also be placed in the global face directory, which is + specified by the <filename>GlobalFaceDir</filename> configuration + option ( normally <filename><share>/pixmaps/faces/</filename>) + and the filename should be the name of the user, optionally with a + <filename>.png</filename>, <filename>.jpg</filename>, etc. appended. + </para> + </sect2> + </sect1> + + <sect1 id="controlling"> + <title>Controlling GDM</title> + + <para> + You can control GDM behavior during runtime in several different ways. + You can either run certain commands, or you can talk to GDM using either + a unix socket protocol, or a FIFO protocol. + </para> + + <sect2 id="commands"> + <title>Commands</title> + + <para> + To stop GDM, you can either send the TERM signal to the main daemon or + run the <command>gdm-stop</command> command which is in the + <filename><sbin>/</filename> directory. To restart GDM, you can + either send the HUP signal to the main daemon or run the + <command>gdm-restart</command> command which is also in the + <filename><sbin>/</filename> directory. To restart GDM but only + after all the users have logged out, you can either send the USR1 + signal to the main daemon or run the + <command>gdm-safe-restart</command> command which is in the + <filename><sbin>/</filename> directory as well. + </para> + + <para> + The <command>gdmflexiserver</command> command can be used to start + new flexible (on demand) displays if your system supports virtual + terminals. This command will normally lock the current session with a + screensaver so that the user can safely walk away from the computer and + let someone else log in. If more that two flexible displays have + started <command>gdmflexiserver</command> will display a pop-up dialog + allowing the user to select which session to continue. The user will + normally have to enter a password to return to the session. On session + exit the system will return to the previous virtual terminal. Run + <command>gdmflexiserver --help</command> to get a listing of possible + options. + </para> + </sect2> + + <sect2 id="fifoprot"> + <title>The FIFO protocol</title> + + <para> + GDM also provides a FIFO called <filename>.gdmfifo</filename> in the + <filename>ServAuthDir</filename> directory + (usually <filename><var>/gdm/.gdmfifo</filename>). You must be + root to use this protocol, and it is mostly used for internal GDM + chatter. It is a very simple protocol where you just echo a command on + a single line to this file. It can be used to tell GDM things such as + restart, suspend the computer, or restart all X servers next time it has + a chance (which would be useful from an X configuration application). + </para> + + <para> + Full and up to date documentation of the commands and their use is + contained in the GDM source tree in the file + <filename>daemon/gdm.h</filename>. Look for the defines starting with + <filename>GDM_SOP_</filename>. The commands which require the + pid of the slave as an argument are the ones that are really used for + internal communication of the slave with the master and should not be + used. + </para> + </sect2> + + <sect2 id="socketprot"> + <title>Socket Protocol</title> + + <para> + GDM provides a unix domain socket for communication at + <filename>/tmp/.gdm_socket</filename>. Using this you can check if + GDM is running, the version of the daemon, the current displays that + are running and who is logged in on them, and if GDM supports it on + your operating system, also the virtual terminals of all the console + logins. The <command>gdmflexiserver</command> command uses this + protocol, for example, to launch flexible (on-demand) displays. + </para> + + <para> + gdmflexiserver accepts the following commands with the --command + option: + </para> + +<screen> +ADD_DYNAMIC_DISPLAY +ALL_SERVERS +ATTACHED_SERVERS +AUTH_LOCAL +CLOSE +FLEXI_XNEST +FLEXI_XNEST_USER +FLEXI_XSERVER +FLEXI_XSERVER_USER +GET_CONFIG +GET_CONFIG_FILE +GET_CUSTOM_CONFIG_FILE +GET_SERVER_LIST +GET_SERVER_DETAILS +GREETERPIDS +QUERY_LOGOUT_ACTION +QUERY_CUSTOM_CMD_LABELS +QUERY_CUSTOM_CMD_NO_RESTART_STATUS +QUERY_VT +RELEASE_DYNAMIC_DISPLAYS +REMOVE_DYNAMIC_DISPLAY +SERVER_BUSY +SET_LOGOUT_ACTION +SET_SAFE_LOGOUT_ACTION +SET_VT +UPDATE_CONFIG +VERSION +</screen> + + <para> + These are described in detail below, including required arguments, + response format, and return codes. + </para> + + <sect3 id="adddynamic"> + <title>ADD_DYNAMIC_DISPLAY</title> +<screen> +ADD_DYNAMIC_DISPLAY: Create a new server definition that will + run on the specified display leaving, it + in DISPLAY_CONFIG state. +Supported since: 2.8.0.0 +Arguments: <display to run on>=<server> + Where <server> is either a configuration named in the + GDM configuration or a literal command name. +Answers: + OK <display> + ERROR <err number> <english error description> + 0 = Not implemented + 2 = Existing display + 3 = No server string + 4 = Display startup failure + 100 = Not authenticated + 200 = Dynamic Displays not allowed + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="allservers"> + <title>ALL_SERVERS</title> +<screen> +ALL_SERVERS: List all displays, including console, remote, xnest. + This can, for example, be useful to figure out if + the display you are on is managed by the gdm daemon, + by seeing if it is in the list. It is also somewhat + like the 'w' command but for graphical sessions. +Supported since: 2.4.2.96 +Arguments: None +Answers: + OK <server>;<server>;... + + <server> is <display>,<logged in user> + + <logged in user> can be empty in case no one logged in yet + + ERROR <err number> <english error description> + 0 = Not implemented + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="attachedservers"> + <title>ATTACHED_SERVERS</title> +<screen> +ATTACHED_SERVERS: List all attached displays. Doesn't list XDMCP + and xnest non-attached displays. +Note: This command used to be named CONSOLE_SERVERS, + which is still recognized for backwards + compatibility. The optional pattern argument + is supported as of version 2.8.0.0. +Supported since: 2.2.4.0 +Arguments: <pattern> (optional) + With no argument, all attached displays are returned. The optional + <pattern> is a string that may contain glob characters '*', '?', and + '[]'. Only displays that match the pattern will be returned. +Answers: + OK <server>;<server>;... + + <server> is <display>,<logged in user>,<vt or xnest + display> + + <logged in user> can be empty in case no one logged + in yet, and <vt> can be -1 if it's not known or not + supported (on non-Linux for example). If the display is an + xnest display and is a console one (that is, it is an xnest + inside another console display) it is listed and instead of + vt, it lists the parent display in standard form. + + ERROR <err number> <english error description> + 0 = Not implemented + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="authlocal"> + <title>AUTH_LOCAL</title> +<screen> +AUTH_LOCAL: Setup this connection as authenticated for + FLEXI_SERVER. Because all full blown + (non-nested) displays can be started only from + users logged in locally, and here GDM assumes + only users logged in from GDM. They must pass + the xauth MIT-MAGIC-COOKIE-1 that they were passed + before the connection is authenticated. +Note: The AUTH LOCAL command requires the + --authenticate option, although only + FLEXI XSERVER uses this currently. +Note: Since 2.6.0.6 you can also use a global + <ServAuthDir>/.cookie, which works for all + authentication except for SET_LOGOUT_ACTION and + QUERY_LOGOUT_ACTION and SET_SAFE_LOGOUT_ACTION + which require a logged in display. +Supported since: 2.2.4.0 +Arguments: <xauth cookie> + <xauth cookie> is in hex form with no 0x prefix +Answers: + OK + ERROR <err number> <english error description> + 0 = Not implemented + 100 = Not authenticated + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="close"> + <title>CLOSE</title> +<screen> +CLOSE: Close sockets connection +Supported since: 2.2.4.0 +Arguments: None +Answers: None +</screen> + </sect3> + + <sect3 id="flexixnest"> + <title>FLEXI_XNEST</title> +<screen> +FLEXI_XNEXT: Start a new flexible nested display. +Note: Supported on older version from 2.2.4.0, later + 2.2.4.2, but since 2.3.90.4 you must supply 4 + arguments or ERROR 100 will be returned. This + will start the nested X server command using + the XAUTHORITY file supplied and as the uid + same as the owner of that file (and same as + you supply). You must also supply the cookie as + the third argument for this display, to prove + that you indeed are this user. Also this file + must be readable ONLY by this user, that is + have a mode of 0600. If this all is not met, + ERROR 100 is returned. +Note: The cookie should be the MIT-MAGIC-COOKIE-1, + the first one GDM can find in the XAUTHORITY + file for this display. If that's not what you + use you should generate one first. The cookie + should be in hex form. +Supported since: 2.3.90.4 +Arguments: <display to run on> <uid of requesting user> + <xauth cookie for the display> <xauth file> +Answers: + OK <display> + ERROR <err number> <english error description> + 0 = Not implemented + 1 = No more flexi servers + 2 = Startup errors + 3 = X failed + 4 = X too busy + 5 = Xnest can't connect + 6 = No server binary + 100 = Not authenticated + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="flexixnestuser"> + <title>FLEXI_XNEST_USER</title> +<screen> +FLEXI_XNEST_USER: Start a new flexible nested display and + initialize the greeter with the given username. +Note: This is a variant of the FLEXI_XNEST command. +Note: The cookie should be the MIT-MAGIC-COOKIE-1, + the first one GDM can find in the XAUTHORITY + file for this display. If that's not what you + use you should generate one first. The cookie + should be in hex form. +Supported since: 2.17.7 +Arguments: <username> <display to run on> <uid of requesting + user> <xauth cookie for the display> <xauth file> +Answers: + OK <display> + ERROR <err number> <english error description> + 0 = Not implemented + 1 = No more flexi servers + 2 = Startup errors + 3 = X failed + 4 = X too busy + 5 = Xnest can't connect + 6 = No server binary + 100 = Not authenticated + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="flexixserver"> + <title>FLEXI_XSERVER</title> +<screen> +FLEXI_XSERVER: Start a new X flexible display. Only supported on + connection that passed AUTH_LOCAL +Supported since: 2.2.4.0 +Arguments: <xserver type> + If no arguments, starts the standard X server +Answers: + OK <display> + ERROR <err number> <english error description> + 0 = Not implemented + 1 = No more flexi servers + 2 = Startup errors + 3 = X failed + 4 = X too busy + 6 = No server binary + 100 = Not authenticated + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="flexixserveruser"> + <title>FLEXI_XSERVER_USER</title> +<screen> +FLEXI_XSERVER_USER: Start a new X flexible display and initialize the + greeter with the given username. Only supported on + connection that passed AUTH_LOCAL +Supported since: 2.17.7 +Arguments: <username> <xserver type> + If no server type specified, starts the standard X server +Answers: + OK <display> + ERROR <err number> <english error description> + 0 = Not implemented + 1 = No more flexi servers + 2 = Startup errors + 3 = X failed + 4 = X too busy + 6 = No server binary + 100 = Not authenticated + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="getconfig"> + <title>GET_CONFIG</title> +<screen> +GET_CONFIG: Get configuration value for key. Useful so + that other applications can request configuration + information from GDM. Any key defined as GDM_KEY_* + in gdm-daemon-config-keys.h is supported. Starting with version + 2.13.0.2, translated keys (such as + "greeter/GdmWelcome[cs]" are supported via GET_CONFIG. + Also starting with version 2.13.0.2 it is no longer necessary to + include the default value (i.e. you can use key + "greeter/IncludeAll" instead of having to use + "greeter/IncludeAll=false". +Supported since: 2.6.0.9 +Arguments: <key> +Answers: + OK <value> + ERROR <err number> <english error description> + 0 = Not implemented + 50 = Unsupported key + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="getconfigfile"> + <title>GET_CONFIG_FILE</title> +<screen> +GET_CONFIG_FILE: Get config file location being used by + the daemon. If the GDM daemon was started + with the --config option, it will return + the value passed in via the argument. +Supported since: 2.8.0.2 +Arguments: None +Answers: + OK <full path to GDM configuration file> + ERROR <err number> <english error description> + 0 = Not implemented + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="getcustomconfigfile"> + <title>GET_CUSTOM_CONFIG_FILE</title> +<screen> +GET_CUSTOM_CONFIG_FILE: Get custom config file location being + used by the daemon. +Supported since: 2.14.0.0 +Arguments: None +Answers: + OK <full path to GDM custom configuration file> + ERROR <err number> <english error description> + 0 = Not implemented + 1 = File not found + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="getserverdetails"> + <title>GET_SERVER_DETAILS</title> +<screen> +GET_SERVER_DETAILS: Get detail information for a specific server. +Supported since: 2.13.0.4 +Arguments: <server> <key> + Key values include: + NAME - Returns the server name + COMMAND - Returns the server command + FLEXIBLE - Returns "true" if flexible, "false" + otherwise + CHOOSABLE - Returns "true" if choosable, "false" + otherwise + HANDLED - Returns "true" if handled, "false" + otherwise + CHOOSER - Returns "true" if chooser, "false" + otherwise + PRIORITY - Returns process priority +Answers: + OK <value> + ERROR <err number> <english error description> + 0 = Not implemented + 1 = Server not found + 2 = Key not valid + 50 = Unsupported key + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="getserverlist"> + <title>GET_SERVER_LIST</title> +<screen> +GET_SERVER_LIST: Get a list of the server sections from + the configuration file. +Supported since: 2.13.0.4 +Arguments: None +Answers: + OK <value>;<value>;... + ERROR <err number> <english error description> + 0 = Not implemented + 1 = No servers found + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="greeterpids"> + <title>GREETERPIDS</title> +<screen> +GREETERPIDS: List all greeter pids so that one can send HUP + to them for config rereading. Of course one + must be root to do that. +Supported since: 2.3.90.2 +Arguments: None +Answers: + OK <pid>;<pid>;... + ERROR <err number> <english error description> + 0 = Not implemented + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="querylogoutaction"> + <title>QUERY_LOGOUT_ACTION</title> +<screen> +QUERY_LOGOUT_ACTION: Query which logout actions are possible + Only supported on connections that passed + AUTH_LOCAL. +Supported since: 2.5.90.0 +Answers: + OK <action>;<action>;... + Where action is one of HALT, REBOOT, SUSPEND or CUSTOM_CMD[0-9]. + An empty list can also be returned if no action is possible. + A '!' is appended to an action if it was already set with + SET_LOGOUT_ACTION or SET_SAFE_LOGOUT_ACTION. Note that + SET_LOGOUT_ACTION has precedence over + SET_SAFE_LOGOUT_ACTION. + ERROR <err number> <english error description> + 0 = Not implemented + 100 = Not authenticated + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="querycustomcmdlabels"> + <title>QUERY_CUSTOM_CMD_LABELS</title> +<screen> + QUERY_CUSTOM_CMD_LABELS: Query labels belonging to exported custom + commands Only supported on connections that + passed AUTH_LOCAL. + Supported since: 2.5.90.0 + Answers: + OK <label1>;<label2>;... + Where labelX is one of the labels belonging to CUSTOM_CMDX + (where X in [0,GDM_CUSTOM_COMMAND_MAX)). An empty list can + also be returned if none of the custom commands are exported + outside login manager (no CustomCommandIsPersistent options + are set to true). + ERROR <err number> <english error description> + 0 = Not implemented + 100 = Not authenticated + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="querycustomcmdnorestartstatus"> + <title>QUERY_CUSTOM_CMD_NO_RESTART_STATUS</title> +<screen> +QUERY_CUSTOM_CMD_NO_RESTART_STATUS: Query NoRestart config options + for each of custom commands Only + supported on connections that + passed AUTH_LOCAL. +Supported since: 2.5.90.0 +Answers: + OK <status> + Where each bit of the status represents NoRestart value for + each of the custom commands. + bit on (1): NoRestart = true, + bit off (0): NoRestart = false. + ERROR <err number> <english error description> + 0 = Not implemented + 100 = Not authenticated + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="queryvt"> + <title>QUERY_VT</title> +<screen> +QUERY_VT: Ask the daemon about which VT we are currently on. + This is useful for logins which don't own + /dev/console but are still console logins. Only + supported on Linux currently, other places will + just get ERROR 8. This is also the way to query + if VT support is available in the daemon in the + first place. Only supported on connections that + passed AUTH_LOCAL. +Supported since: 2.5.90.0 +Arguments: None +Answers: + OK <vt number> + ERROR <err number> <english error description> + 0 = Not implemented + 8 = Virtual terminals not supported + 100 = Not authenticated + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="releasedynamic"> + <title>RELEASE_DYNAMIC_DISPLAYS</title> +<screen> +RELEASE_DYNAMIC_DISPLAYS: Release dynamic displays currently in + DISPLAY_CONFIG state +Supported since: 2.8.0.0 +Arguments: <display to release> +Answers: + OK <display> + ERROR <err number> <english error description> + 0 = Not implemented + 1 = Bad display number + 100 = Not authenticated + 200 = Dynamic Displays not allowed + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="removedynamic"> + <title>REMOVE_DYNAMIC_DISPLAY</title> +<screen> +REMOVE_DYNAMIC_DISPLAY: Remove a dynamic display, killing the server + and purging the display configuration +Supported since: 2.8.0.0 +Arguments: <display to remove> +Answers: + OK <display> + ERROR <err number> <english error description> + 0 = Not implemented + 1 = Bad display number + 100 = Not authenticated + 200 = Dynamic Displays not allowed + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="serverbusy"> + <title>SERVER_BUSY</title> +<screen> +SERVER_BUSY: Returns true if half or more of the daemon's sockets + are busy, false otherwise. Used by slave programs + which want to ensure they do not overwhelm the + sever. +Supported since: 2.13.0.8 +Arguments: None +Answers: + OK <value> + ERROR <err number> <english error description> + 0 = Not implemented + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="setlogoutaction"> + <title>SET_LOGOUT_ACTION</title> +<screen> +SET_LOGOUT_ACTION: Tell the daemon to halt/restart/suspend after + slave process exits. Only supported on + connections that passed AUTH_LOCAL. +Supported since: 2.5.90.0 +Arguments: <action> + NONE Set exit action to 'none' + HALT Set exit action to 'halt' + REBOOT Set exit action to 'reboot' + SUSPEND Set exit action to 'suspend' + CUSTOM_CMD[0-9] Set exit action to 'custom command [0-9]' +Answers: + OK + ERROR <err number> <english error description> + 0 = Not implemented + 7 = Unknown logout action, or not available + 100 = Not authenticated + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="setsafelogoutaction"> + <title>SET_SAFE_LOGOUT_ACTION</title> +<screen> +SET_SAFE_LOGOUT_ACTION: Tell the daemon to halt/restart/suspend + after everybody logs out. If only one + person logs out, then this is obviously + the same as the SET_LOGOUT_ACTION. Note + that SET_LOGOUT_ACTION has precedence + over SET_SAFE_LOGOUT_ACTION if it is set + to something other then NONE. If no one + is logged in, then the action takes effect + effect immediately. Only supported on + connections that passed AUTH_LOCAL. +Supported since: 2.5.90.0 +Arguments: <action> + NONE Set exit action to 'none' + HALT Set exit action to 'halt' + REBOOT Set exit action to 'reboot' + SUSPEND Set exit action to 'suspend' + CUSTOM_CMD[0-9] Set exit action to 'custom command [0-9]' +Answers: + OK + ERROR <err number> <english error description> + 0 = Not implemented + 7 = Unknown logout action, or not available + 100 = Not authenticated + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="setvt"> + <title>SET_VT</title> +<screen> +SET_VT: Change to the specified virtual terminal. + This is useful for logins which don't own /dev/console + but are still console logins. Only supported on Linux + currently, other places will just get ERROR 8. + Only supported on connections that passed AUTH_LOCAL. +Supported since: 2.5.90.0 +Arguments: <vt> +Answers: + OK + ERROR <err number> <english error description> + 0 = Not implemented + 8 = Virtual terminals not supported + 9 = Invalid virtual terminal number + 100 = Not authenticated + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="updateconfig"> + <title>UPDATE_CONFIG</title> +<screen> +UPDATE_CONFIG: Tell the daemon to re-read a key from the + GDM configuration file. Any user can request + that values are re-read but the daemon will + only do so if the file has been modified + since GDM first read the file. Only users + who can change the GDM configuration file + (normally writable only by the root user) can + actually modify the GDM configuration. This + command is useful to cause the GDM to update + itself to recognize a change made to the GDM + configuration file by the root user. + + Starting with version 2.13.0.0, all GDM keys are + supported except for the following: + + daemon/PidFile + daemon/ConsoleNotify + daemon/User + daemon/Group + daemon/LogDir + daemon/ServAuthDir + daemon/UserAuthDir + daemon/UserAuthFile + daemon/UserAuthFBDir + + GDM also supports the following Psuedokeys: + + xdmcp/PARAMETERS (2.3.90.2) updates the following: + xdmcp/MaxPending + xdmcp/MaxSessions + xdmcp/MaxWait + xdmcp/DisplaysPerHost + xdmcp/HonorIndirect + xdmcp/MaxPendingIndirect + xdmcp/MaxWaitIndirect + xdmcp/PingIntervalSeconds (only affects new connections) + + xservers/PARAMETERS (2.13.0.4) updates the following: + all [server-foo] sections. + + Supported keys for previous versions of GDM: + + security/AllowRoot (2.3.90.2) + security/AllowRemoteRoot (2.3.90.2) + security/AllowRemoteAutoLogin (2.3.90.2) + security/RetryDelay (2.3.90.2) + security/DisallowTCP (2.4.2.0) + daemon/Greeter (2.3.90.2) + daemon/RemoteGreeter (2.3.90.2) + xdmcp/Enable (2.3.90.2) + xdmcp/Port (2.3.90.2) + daemon/TimedLogin (2.3.90.3) + daemon/TimedLoginEnable (2.3.90.3) + daemon/TimedLoginDelay (2.3.90.3) + greeter/SystemMenu (2.3.90.3) + greeter/ConfigAvailable (2.3.90.3) + greeter/ChooserButton (2.4.2.0) + greeter/SoundOnLoginFile (2.5.90.0) + daemon/AddGtkModules (2.5.90.0) + daemon/GtkModulesList (2.5.90.0) +Supported since: 2.3.90.2 +Arguments: <key> + <key> is just the base part of the key such as + "security/AllowRemoteRoot" +Answers: + OK + ERROR <err number> <english error description> + 0 = Not implemented + 50 = Unsupported key + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + + <sect3 id="queryversion"> + <title>VERSION</title> +<screen> +VERSION: Query GDM version +Supported since: 2.2.4.0 +Arguments: None +Answers: + GDM <gdm version> + ERROR <err number> <english error description> + 200 = Too many messages + 999 = Unknown error +</screen> + </sect3> + </sect2> + </sect1> + + <!-- ============= GDM Commands ============================= --> + + <sect1 id="binaries"> + <title>GDM Commands</title> + + <sect2 id="bindir_binaries"> + <title>GDM User Commands</title> + + <para> + The GDM package provides the following different commands in + <filename>bindir</filename> intended to be used by the end-user: + </para> + + <sect3 id="gdmxnestchoosercommandline"> + <title><command>gdmXnestchooser</command> and + <command>gdmXnest</command> Command Line Options</title> + + <para> + The <command>gdmXnestchooser</command> command automatically gets + the correct display number, sets up access, and runs the nested + X server command with the "-indirect localhost" argument. + This provides an XDMCP chooser program. You can also supply as an + argument the hostname whose chooser should be displayed, so + <command>gdmXnestchooser somehost</command> will run the XDMCP + chooser from host <command>somehost</command> inside a nested + X server session. You can make this command do a direct query + instead by passing the <command>-d</command> option as well. In + addition to the following options, this command also supports + standard GNOME options. + </para> + + <variablelist> + <title><command>gdmXnestchooser</command> Command Line Options</title> + + <varlistentry> + <term>-x, --xnest=STRING</term> + <listitem> + <para> + Nested X server command line, default is defined by the + <filename>Xnest</filename> configuration option. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-o, --xnest-extra-options=OPTIONS</term> + <listitem> + <para> + Extra options for nested X server, default is no options. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-n, --no-query</term> + <listitem> + <para> + Just run nested X server, no query (no chooser) + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-d, --direct</term> + <listitem> + <para> + Do direct query instead of indirect (chooser) + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-B, --broadcast</term> + <listitem> + <para> + Run broadcast instead of indirect (chooser) + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-b, --background</term> + <listitem> + <para> + Run in background + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>--no-gdm-check</term> + <listitem> + <para> + Don't check for running GDM + </para> + </listitem> + </varlistentry> + </variablelist> + </sect3> + + <sect3 id="gdmflexichoosercommandline"> + <title><command>gdmflexichooser</command> Command Line Options</title> + + <para> + The <command>gdmflexiserver</command> command provides three + features. It can be used to run flexible (on demand) X displays, + to run a flexible display via nested X server, and to send commands to + the GDM daemon process. + </para> + + <para> + Starting a flexible X display will normally lock the current session + with a screensaver and will redisplay the GDM login screen so a second + user can log in. This feature is only available on systems that + support virtual terminals and have them enabled. This feature is + useful if you are logged in as user A, and user B wants to log in + quickly but user A does not wish to log out. The X server takes + care of the virtual terminal switching so it works transparently. + If there is more than one running display defined with flexible=true, + then the user is shown a dialog that displays the currently running + sessions. The user can then pick which session to continue and will + normally have to enter the password to unlock the screen. + </para> + + <para> + Nested displays works on systems that do not support virtual + terminals. This option starts a flexible display in a window in the + current session. This does not lock the current session, so is not + as secure as a flexible server started via virtual terminals. + </para> + + <para> + The <command>gdmflexiserver --command</command> option provides a way + to send commands to the GDM daemon and can be used to debug problems + or to change the GDM configuration. + </para> + + <para> + In addition to the following options, + <command>gdmflexiserver</command> also supports standard GNOME + options. + </para> + + <variablelist> + <title><command>gdmflexichooser</command> Command Line Options</title> + + <varlistentry> + <term>-c, --command=COMMAND</term> + <listitem> + <para> + Send the specified protocol command to GDM + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-n, --xnest</term> + <listitem> + <para> + Start a flexible X display in Nested mode + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-l, --no-lock</term> + <listitem> + <para> + Do not lock current screen + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-d, --debug</term> + <listitem> + <para> + Turns on debugging output which gets sent to syslog. Same as + turning on debug in the configuration file. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-a, --authenticate</term> + <listitem> + <para> + Authenticate before running --command + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-s, --startnew</term> + <listitem> + <para> + Starts a new flexible display without displaying a dialog + asking the user if they wish to continue any existing + sessions. + </para> + </listitem> + </varlistentry> + </variablelist> + </sect3> + + <sect3 id="gdmdynamiccommandline"> + <title><command>gdmdynamic</command> Command Line Options</title> + + <para> + The <command>gdmdynamic</command> command which creates, runs, and + removes displays (X servers) on demand. + </para> + + <para> + <command>gdmdynamic</command> allows the management of displays in a + dynamic fashion. It is typically used in environments where it is not + possible to list the possible displays in the GDM configuration files. + The <command>gdmdynamic</command> command can be used to create a new + display on a particular display number, run all newly created displays, + or remove a display. The <command>gdmdynamic</command> command can also + be used to list all attached displays, or only attached displays that + match a pattern. + </para> + + <para> + This program is designed to manage multiple simultaneous requests and + works to avoid flooding the daemon with requests. If the sockets + connection is busy, it will sleep and retry a certain number of times + that can be tuned with the -s and -t options. + </para> + + <variablelist> + <title><command>gdmdynamic</command> Command Line Options</title> + + <varlistentry> + <term/> + <listitem> + <para><emphasis> + One of the following options can be used per instance: + </emphasis></para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-a display=server</term> + <listitem> + <para> + Add a new display configuration, leaving it in the DISPLAY_CONFIG + state. For example, + <command>"-a 2=StandardServerTwo"</command> + <command>"-a 3=/usr/X11R6/bin/X -dev /dev/fb2"</command> + </para> + <para> + The display will not actually be started until the display is released + by calling <command>gdmdynamic</command> again with the -r option. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-r</term> + <listitem> + <para> + Release (run) all displays waiting in the DISPLAY_CONFIG state. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-d display</term> + <listitem> + <para> + Delete a display, killing the X server and purging the + display configuration. For example, "-d 3". + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-l [pattern]</term> + <listitem> + <para> + List displays via the ATTACHED_SERVERS <command>gdmflexiserver</command> + command. Without a pattern lists all attached displays. With a pattern + will match using glob characters '*', '?', and '[]'. For example: + <command>"-l Standard*"</command> + <command>"-l *Xorg*"</command> + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term/> + <listitem> + <para><emphasis> + These options can be added to the above: + </emphasis></para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-v</term> + <listitem> + <para> + Verbose mode. Prinr diagnostic messages about each message sent + to GDM. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-b</term> + <listitem> + <para> + Background mode. Fork child to do the work and return immediately. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-t RETRY</term> + <listitem> + <para> + If the daemon socket is busy, <command>gdmdynamic</command> will + retry to open the connection the specified RETRY number of times. + Default value is 15. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>-s SLEEP</term> + <listitem> + <para> + If the daemon socket is busy, <command>gdmdynamic</command> will + sleep an amount of time between retries. A random number of + seconds 0-5 is added to the SLEEP value to help ensure that + multiple calls to gdmdynamic do not all try to restart at the + same time. A SLEEP value of zero causes the sleep time to be + 1 second. Default value is 8 seconds. + </para> + </listitem> + </varlistentry> + + </variablelist> + </sect3> + + <sect3 id="gdmphotosetupcommandline"> + <title><command>gdmphotosetup</command> Command Line Options</title> + + <para> + Allows the user to select an image that will be used as the user's + photo by GDM's face browser, if enabled by GDM. The selected file + is stored as <filename>~/.face</filename>. This command accepts + standard GNOME options. + </para> + </sect3> + + <sect3 id="gdmthemetestercommandline"> + <title><command>gdmthemetester</command> Command Line Options</title> + + <para> + <command>gdmthemetester</command> takes two parameters. The first + parameter specifies the environment and the second parameter + specifies the path name or the name of a theme to view. + + This is a tool for viewing a theme outside of GDM. It is useful for + testing or viewing themes. <command>gdmthemetester</command> requires + that the system support <command>gdmXnest</command>. + + Note that themes can display differently depending on the theme's + "Show mode". <command>gdmthemetester</command> allows + viewing the themes in different modes via the environment option. + Valid environment values and their meanings follow: + +<screen> +console - In console mode. +console-timed - In console non-flexi mode. +flexi - In flexi mode. +xdmcp - In remote (XDMCP) mode. +remote-flexi - In remote (XDMCP) & flexi mode. +</screen> + </para> + </sect3> + </sect2> + + <sect2 id="sbindir_binaries"> + <title>GDM Root User Commands</title> + + <para> + The GDM package provides the following different commands in + <filename>sbindir</filename> intended to be used by the root user: + </para> + + <sect3 id="gdmcommandline"> + <title><command>gdm</command> and <command>gdm-binary</command> + Command Line Options</title> + + <para> + The <command>gdm</command> command is really just a script which + runs the <command>gdm-binary</command>, passing along any options. + Before launching <command>gdm-binary</command>, the gdm wrapper script + will source the <filename><etc>/profile</filename> file to set + the standard system environment variables. In order to better support + internationalization, it will also set the LC_MESSAGES environment + variable to LANG if neither LC_MESSAGES or LC_ALL are set. If you + really need to set some additional environment before launching GDM, + you can do so in this script. + </para> + + <variablelist> + <title><command>gdm</command> and <command>gdm-binary</command> + Command Line Options</title> + + <varlistentry> + <term>--help</term> + <listitem> + <para> + Gives a brief overview of the command line options. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>--nodaemon</term> + <listitem> + <para> + If this option is specified, then GDM does not fork into the + background when run. You can also use a single-dash version, + "-nodaemon" for compatibility with other display + managers. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>--no-console</term> + <listitem> + <para> + Tell the daemon that it should not run anything on the console. + This means that none of the local servers from the + <filename>[servers]</filename> section will be run, and the + console will not be used for communicating errors to the user. + An empty <filename>[servers]</filename> section automatically + implies this option. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>--config=CONFIGFILE</term> + <listitem> + <para> + Specify an alternative configuration file. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>--preserve-ld-vars</term> + <listitem> + <para> + When clearing the environment internally, preserve all variables + starting with LD_. This is mostly for debugging purposes. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>--version</term> + <listitem> + <para> + Print the version of the GDM daemon. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>--wait-for-go</term> + <listitem> + <para> + If started with this option, gdm will init, but only start the + first local display and then wait for a GO message in the fifo + protocol. No greeter will be shown until the GO message is + sent. Also flexiserver requests will be denied and XDMCP will + not be started until GO is given. This is useful for + initialization scripts which wish to start X early, but where + you don't yet want the user to start logging in. So the script + would send the GO to the fifo once it is ready and GDM will + then continue. This functionality was added in version + 2.5.90.0. + </para> + </listitem> + </varlistentry> + </variablelist> + </sect3> + + <sect3 id="gdmsetupcommandline"> + <title><command>gdmsetup</command> Command Line Options</title> + + <para> + <command>gdmsetup</command> runs a graphical application for modifying + the GDM configuration file. Normally on systems that support + the PAM userhelper, this is setup such that when you run + <command>gdmsetup</command> as an ordinary user, it will first + ask you for your root password before starting. Otherwise, this + application may only be run as root. This application supports + standard GNOME options. + </para> + </sect3> + + <sect3 id="gdmrestartcommandline"> + <title><command>gdm-restart</command> Command Line Options</title> + + <para> + <command>gdm-restart</command> stops and restarts GDM by sending + the GDM daemon a HUP signal. This command will immediately terminate + all sessions and log out users currently logged in with GDM. + </para> + </sect3> + + <sect3 id="gdmsaferestartcommandline"> + <title><command>gdm-safe-restart</command> Command Line Options</title> + + <para> + <command>gdm-safe-restart</command> stops and restarts GDM by + sending the GDM daemon a USR1 signal. GDM will be restarted as soon + as all users log out. + </para> + </sect3> + + <sect3 id="gdmstopcommandline"> + <title><command>gdm-stop</command> Command Line Options</title> + + <para> + <command>gdm-stop</command> stops GDM by sending the GDM daemon + a TERM signal. + </para> + </sect3> + </sect2> + + <sect2 id="libexecdir_binaries"> + <title>GDM Internal Commands</title> + + <para> + The GDM package provides the following different commands in + <filename>libexecdir</filename> intended to be used by the gdm + daemon process. + </para> + + <sect3 id="gdmgreeterlogincommandline"> + <title><command>gdmchooser</command> and <command>gdmlogin</command> + Command Line Options</title> + + <para> + The <command>gdmgreeter</command> and <command>gdmlogin</command> + are two different login applications, either can be used by GDM. + <command>gdmgreeter</command> is themeable with GDM themes while + <command>gdmlogin</command> is themable with GTK+ themes. These + applications are normally executed by the GDM daemon. Both commands + support standard GNOME options. + </para> + </sect3> + + <sect3 id="gdmchoosercommandline"> + <title><command>gdmchooser</command> Command Line Options</title> + + <para> + The <command>gdmchooser</command> is the XDMCP chooser application. + The <command>gdmchooser</command> is normally executed by the GDM + daemon. It supports the following options for XDM compatibility. + This command supports standard GNOME options and is found in + support standard GNOME options. + </para> + + <variablelist> + <title><command>gdmchooser</command> Command Line Options</title> + + <varlistentry> + <term>--xdmaddress=SOCKET</term> + <listitem> + <para> + Socket for XDM communication. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>--clientaddress=ADDRESS</term> + <listitem> + <para> + Client address to return in response to XDM. This option is for + running gdmchooser with XDM, and is not used within GDM. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>--connectionType=TYPE</term> + <listitem> + <para> + Connection type to return in response to XDM. This option is for + running gdmchooser with XDM, and is not used within GDM. + </para> + </listitem> + </varlistentry> + </variablelist> + </sect3> + + <sect3 id="gdm-ssh-session"> + <title><command>gdm-ssh-session</command></title> + + <para> + The <command>gdm-ssh-session</command> is normally executed by the + GDM daemon when starting a secure remote connection through ssh. + It does not take any options. + </para> + </sect3> + </sect2> + </sect1> + + <!-- ============= Theme manual ============================= --> + + <sect1 id="thememanual"> + <title>Themed Greeter</title> + + <para> + This section describes the creation of themes for the Themed + Greeter. For examples including screenshots, see the standard installed + themes and the themes from + <ulink type="http" url="http://art.gnome.org/themes/gdm_greeter/"> + the theme website</ulink>. + </para> + + <sect2 id="themeover"> + <title>Theme Overview</title> + + <para> + GDM Themes can be created by creating an XML file that follows the + specification in gui/greeter/greeter.dtd. Theme files are stored + in the directory + <filename><share>/gdm/themes/<theme_name></filename>. + Usually this would be under <filename>/usr/share</filename>. The theme + directory should contain a file called + <filename>GdmGreeterTheme.desktop</filename> which has similar format + to other .desktop files and looks like: + </para> + +<screen> +[GdmGreeterTheme] +Encoding=UTF-8 +Greeter=circles.xml +Name=Circles +Description=Theme with blue circles +Author=Bond, James Bond +Copyright=(c) 2002 Bond, James Bond +Screenshot=screenshot.png +</screen> + + <para> + The Name, Description, Author and Copyright fields can be translated + just like the other <filename>.desktop</filename>files. All the files + that are mentioned should be in the theme directory itself. The + Screenshot field points to a file which should be a 200x150 screenshot + of the theme in action (it is OK not to have one, but it makes it nicer + for user). The Greeter field points to an XML file that contains the + description of the theme. The description will be given later. + </para> + + <para> + Once you have theme ready and installed you can test it with the + installed <command>gdmthemetester</command> script. This script + assumes that the X server supports a nested server command. This + command takes two arguments, first the environment that should be used. + This is one of console, console-timed, flexi, remote-flexi, xdmcp. + Where console is a standard console login, console-timed is a console + login with a timed login going on, flexi is for any local flexible + display, remote-flexi is for flexi displays that are not local (such + as an Xnest flexiserver run from a remote display) and xdmcp is for + remote XDMCP connections. The second argument is the theme name. So + for example to test how things look in the XDMCP mode with the circles + theme you would run: + </para> + +<screen> +<command>gdmthemetester xdmcp circles</command> +</screen> + + <para> + Be sure to test all the environments with your theme, and make sure to + test how the caps lock warning looks by pressing caps lock. This is + also a good way to take screenshots, just take a screenshot of the + nested display window. This can be done in GNOME by focusing the + nested login window and pressing Alt-PrintScreen. + </para> + + <para> + Once you have all this done, then make a tarball that contains the + directory name (so that you could just untar it in the + <filename><share>/gdm/themes</filename> directory). And this is + the tarball you distribute and people can install from the graphical + configuration application. You can do this with the commands: +<screen> +cd <share>/gdm/themes +tar czvf <theme_name>.tar.gz <theme_name>/ +</screen> + </para> + </sect2> + + <sect2 id="descofthemeformat"> + <title>Detailed Description of Theme XML format</title> + + <sect3 id="greetertag"> + <title>greeter tag</title> + + <para> + The GDM theme format is specified in XML format contained + within a <greeter> tag. You may specify a GTK+ theme to + be used with this theme by using the gtk-theme element in the + greeter tag as in the following example. + </para> + +<screen> +<?xml version="1.0" encoding="UTF-8"?> +<!DOCTYPE greeter SYSTEM "greeter.dtd"> +<greeter gtk-theme="Crux"> +[...] +</greeter> +</screen> + + <para> + Contained within the greeter tag can be the nodes described + in the next sections of this document. Some of these nodes are + containers (box nodes, rect item nodes) which can be used to + organize how to display the nodes that the user sees and interacts + with (such as button, pixmap and entry item nodes). + </para> + </sect3> + + <sect3 id="boxnodes"> + <title>Box Nodes</title> + + <para> + Box nodes are container nodes for item nodes. Box nodes are + specified as follows: +<screen> +<box orientation="alignment" min-width="num" +xpadding="num" ypadding="num" spacing="num" +homogeneous="bool"> +</screen> + Where "num" means number and bool means either + "true" or "false" The alignment value can be + either "horizontal" or "vertical". If you leave + any property off it will default to zero or "false" in + case of "homogeneous" and "vertical" for the + orientation. + </para> + + <para> + If the box is homogeneous then the children are allocated equal + amount of space. + </para> + + <para> + The "min-width" must be specified in pixels. Obviously + there is also a corresponding "min-height" property as + well. + </para> + </sect3> + + <sect3 id="fixednodes"> + <title>Fixed Nodes</title> + + <para> + Fixed is a container that has its children scattered about + laid out with precise coordinates. The size of this container + is the biggest rectangle that contains all the children. Fixed + has no extra properties and so you just use: +<screen> +<fixed> +</screen> + Then you put other items with proper position nodes inside this. + </para> + + <para> + The "toplevel" node is really just like a fixed node. + </para> + </sect3> + + <sect3 id="itemnodes"> + <title>Item Nodes</title> + + <para> + A GDM Theme is created by specifying a hierarchy of item and box + nodes. Item nodes can have the following value for + "type": + </para> + + <variablelist> + <varlistentry> + <term>button</term> + <listitem> + <para> + A button field. This field uses a GTK+ button. It is also + possible to make a "rect" item act like a button by setting + its button element to true. However it is better to use + GTK+ buttons in GDM themes since these are accessible to + users with disabilities. Also, GTK+ buttons can be + themed. This feature is supported in GDM 2.14.6 and later. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>entry</term> + <listitem> + <para> + Text entry field. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>label</term> + <listitem> + <para> + A text label. Must have a "text" node to specify the + text. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>list</term> + <listitem> + <para> + A face browser widget. Only useful if the face browser is + enabled via the configuration. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>pixmap</term> + <listitem> + <para> + An pixmap image in a format that gdk-pixbuf supports like + PNG, JPEG, Tiff, etc...) + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>rect</term> + <listitem> + <para> + Rectangle. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>svg</term> + <listitem> + <para> + Scaled Vector Graphic image. + </para> + </listitem> + </varlistentry> + </variablelist> + + <para> + For example: +<screen> +<item type="label"> +</screen> + Items can specify ID values which gives them a specific look and feel + or formatting. Furthermore you can customize the login process by + adding custom widgets with custom id's for some items (currently only + the list item) + </para> + + <para> + Entry items can have id values as follows: + </para> + + <variablelist> + <varlistentry> + <term>user-pw-entry</term> + <listitem> + <para> + Entry field for userid and password entry. This is the field + used for responses for the PAM/GDM questions (Username, + Password, etc..). + </para> + </listitem> + </varlistentry> + </variablelist> + + <para> + List items by default display as lists, but the + combo="true" attribute can be used to specify combo box + style (combo style supported since GDM 2.16.2). Some predefined + lists may be included in a theme by using the following id values. + Customized lists may also be defined, which are explained below. + </para> + + <variablelist> + <varlistentry> + <term>session</term> + <listitem> + <para> + A list of available sessions, which allows the user to pick + the session to use. Supported since GDM 2.16.2. + </para> + </listitem> + </varlistentry> + </variablelist> + + <variablelist> + <varlistentry> + <term>language</term> + <listitem> + <para> + A list of available languages, which allows the user to pick + the language to use. Supported since GDM 2.16.2. + </para> + </listitem> + </varlistentry> + </variablelist> + + <variablelist> + <varlistentry> + <term>userlist</term> + <listitem> + <para> + A Face Browser list, so that users can pick their username + by clicking on this instead of typing. This obviously exposes + the usernames to viewers of the login screen, and is not + recommended for users who feel that this reduces security. + The face browser does not support combo box style. + </para> + </listitem> + </varlistentry> + </variablelist> + + <variablelist> + <varlistentry> + <term>userlist-rect</term> + <listitem> + <para> + This id can be specified for the <rect> object containing + the userlist and if the userlist is empty then this rectangle + will not be shown. This allows the theme to define something + like an area with a different color and/or alpha to surround + the userlist, but only if there are users to display. + Supported since 2.16.2. + </para> + </listitem> + </varlistentry> + </variablelist> + + <para> + Furthermore, you can have an arbitrary id (I'd recommend starting + the id with 'custom' not to conflict with future additions to this + spec) and ask extra information of the user. See the section + 'Custom Widgetry' + </para> + + <para> + Label items can have id values as follows: + </para> + + <variablelist> + <varlistentry> + <term>clock</term> + <listitem> + <para> + Label that displays the date and time. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>pam-prompt</term> + <listitem> + <para> + Label that displays the PAM prompt. This is the prompt that PAM + uses to ask for username, password, etc... + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>pam-error</term> + <listitem> + <para> + Label that displayst PAM/GDM error messages. Such as when user + can't log in. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>pam-error-logo</term> + <listitem> + <para> + An image that will be displayed only when a pam-error message + is being displayed. This is useful for displaying an + "Attention" icon, for example. This feature is + supported in GDM 2.14.6 and later. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>pam-message</term> + <listitem> + <para> + Label that displays the PAM message. These are messages that + PAM/GDM gives about state of the account, help about the + prompts and other information. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>timed-label</term> + <listitem> + <para> + Label that displays timed login information. + </para> + </listitem> + </varlistentry> + </variablelist> + + <para> + Rectangles can have id values as follows: + </para> + + <variablelist> + <varlistentry> + <term>caps-lock-warning</term> + <listitem> + <para> + Displays an icon that shows if the + CAPS LOCK key is depressed. This rectangle + will be hidden/shown appropriately + </para> + </listitem> + </varlistentry> + </variablelist> + + <para> + If an item is of type rect, the item can be a button. Buttons + must also include a "button" value as follows: +<screen> +<item type="rect" id="disconnect_button" button="true">. +</screen> + </para> + + <para> + Possible values for button ids are as follows. + </para> + + <variablelist> + <varlistentry> + <term>chooser_button</term> + <listitem> + <para> + Runs the XDMCP chooser. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>config_button</term> + <listitem> + <para> + Runs the GDM configuration application. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>custom_cmd_button[0-9]</term> + <listitem> + <para> + Runs the <filename>n-th</filename> custom command. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>disconnect_button</term> + <listitem> + <para> + Disconnect from remote session. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>language_button</term> + <listitem> + <para> + Displays the language selection dialog. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>halt_button</term> + <listitem> + <para> + Halt (shuts down) the system. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>reboot_button</term> + <listitem> + <para> + Restart the system. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>session_button</term> + <listitem> + <para> + List and select from available sessions. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>suspend_button</term> + <listitem> + <para> + Suspend the system. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term>system_button</term> + <listitem> + <para> + Perform halt/restart/suspend/etc. options (if allowed by GDM + configuration). Also allows user to run configurator if user + enters root password (again if allowed by GDM configuration). + This is usually now labeled Actions, and referred to as the + Actions menu. + </para> + </listitem> + </varlistentry> + </variablelist> + + <para> + By default, the GDM login screen will disappear after authentication. + This can result in flicker between the login screen and the session. + The "background" property allows users to specify what + elements of the theme are the background image. When used, this + will cause GDM to remove all non-background items from the display + and render the remaining "background" items to the root + window. This can be used to create a smooth transition between the + login screen and the session. For example, if the GDM theme and the + session use the same background, then this will make the background + apear seamless. + </para> + + <para> + Item nodes may specify a "background" property which can be + set to "true" or "false" (not setting this + property is equivalent to "false"), as follows: + </para> + +<screen> +<item type="rect" background="true"> + <normal file="background.svg"/> + <pos x="0" y="0" width="100%" height="-75"/> +</item> +</screen> + + <para> + If no item node has "background" property set, then the + background is not modified when greeter exits. + </para> + + <para> + To use a different background for login transition than the one + used for login, insert a "item" node with "background" property set to "true" to draw login transition background before "item"e; node (without any "background" property) used for greeter background. For instance : + </para> +<screen> +<?xml version="1.0" encoding="UTF-8"?> +<!DOCTYPE greeter SYSTEM "greeter.dtd"> + <greeter> + + <item type="rect" background="true"> + <normal file="background_for_login.svg"/> + <pos x="0" y="0" width="100%" height="100%"/> + </item> + <item type="rect"> + <normal file="background_for_greeter.svg"/> + <pos x="0" y="0" width="100%" height="100%"/> + </item> +[...] +</greeter> +</screen> + </sect3> + + <sect3 id="positionnodes"> + <title>Position Node</title> + + <para> + Each item can specify its position and size via the "pos" + node. For example: +<screen> +<pos x="0" y="4" width="100%" height="100%"/> +</screen> + </para> + + <para> + Both position and size can be given in percent and it will be taken + as the percentage of the size of the current container. For toplevel + items it's the percentage of the whole screen. + </para> + + <para> + For x and y, you can also specify a negative position which means + position from the right or bottom edge. But this only applies with + absolute coordinates. With percentage you can specify negative + position and it will be still from the same edge. + </para> + + <para> + The position also specifies the anchor of the item, this can be + "n" "ne" "e" "se" + "s" "sw" "w" and "nw" or + "center" which stand for the different edges/corners or + "center" for center. For example: +<screen> +<pos x="10%" y="50%" anchor="w" width="80%" height="95"/> +</screen> + </para> + + <para> + If the item contains a box, you can specify width and height to be + "box" to mean that they are supposed to be the width and + height of the box, that is the items in the box plus the padding. + </para> + + <para> + If the item contains an SVG image, you can specify width and height + to be "scale" to mean that the SVG image should be scaled + to fit the requested area. + </para> + + <para> + You can also specify an "expand" property to either be + "true" or false. If true then the child will be expanded + in the box as much as possible (that is it will be given more space + if available). + </para> + + <para> + There are two extra properties you can specify (as of 2.4.4.3) for + labels (and labels only). The first is "max-width" which + will specify the maximum width of the label in pixels. And the + second is "max-screen-percent-width" which specifies the + maximum percentage of the screen width that the label can occupy. + By default no label will occupy more then 90% of the screen by width. + An example may be: +<screen> +<item type="label"> +<pos x="10%" max-screen-percent-width="50%"/> +</screen> + </para> + </sect3> + + <sect3 id="shownodes"> + <title>Show Node</title> + + <para> + Some items may only display in certain modes, like when doing a + remote display. Multiple values can be specified and must be + separated with commas. The following values are possible: + </para> + + <para> + <filename>console</filename> - In console mode. + </para> + <para> + <filename>console-fixed</filename> - In console non-flexi mode. + </para> + <para> + <filename>console-flexi</filename> - In console & flexi mode. + </para> + <para> + <filename>flexi</filename> - In flexi mode. + </para> + <para> + <filename>remote</filename> - In remote mode. + </para> + <para> + <filename>remote-flexi</filename> - In remote & flexi mode. + </para> + + <para> + For example: +<screen> +<show modes="flexi,remote"/> +</screen> + </para> + + <para> + You can also specify the "type" value to indicate that + certain items should only be displayed if the type is true. Valid + values include the following: + </para> + + <para> + <filename>chooser</filename>, if ChooserButton is set to + "true" in the GDM configuration. + </para> + <para> + <filename>config</filename>, if ConfigAvailable is set to + "true" in the GDM configuration. + </para> + <para> + <filename>custom_cmd[0-9]</filename>, if <filename>n-th</filename> + CustomCommand is specified in the GDM configuration. + </para> + <para> + <filename>halt</filename>, if HaltDaemon is specified in + the GDM configuration. + </para> + <para> + <filename>reboot</filename>, if RebootCommand is specified in + the GDM configuration. + </para> + <para> + <filename>suspend</filename>, if SuspendCommand is specified in + the GDM configuration. + </para> + <para> + <filename>system</filename>, if SystemMenu is specified in + the GDM configuration. + </para> + <para> + <filename>timed</filename>, if TimedLoginEnabled is set to + "true" in the GDM configuration. + </para> + + <para> + For example: +<screen> +<show modes="console" type="system"/> +</screen> + </para> + + <para> + Alternatively, you can specify a "min-screen-width" or + "min-screen-height" value to indicate that certain + items should only be displayed if the screen resolution is the + at least the given required size. + </para> + + <para> + For example: +<screen> +<show min-screen-height="768"/> +</screen> + </para> + + <para> + Note that if SystemMenu is off then the halt, restart, suspend, + chooser and config choices will not be shown, so this is a global + toggle for them all. See some of the standard themes for how the + show modes are used. + </para> + </sect3> + + <sect3 id="noractprenodes"> + <title>Normal/Active/Prelight Nodes</title> + + <para> + Depending on the item type (except for userlist - refer to Color node + below), it can specify its color, font, or image via the following + tags: + </para> + + <para> + <filename>normal</filename> - normal state. + </para> + <para> + <filename>active</filename> - when the item has active focus. + </para> + <para> + <filename>prelight</filename> - when the mouse is hovering over the + item. + </para> + + <para> + When item is "rect" (alpha can be omitted and defaults to + 0.0): +<screen> +<normal color="#ffffff" alpha="0.0"> +</screen> + </para> + + <para> + When item is "label" +<screen> +<normal color="#ffffff" font="Sans 14"/> +</screen> + </para> + + <para> + When the item type is "pixmap" or "SVG", then the + normal, active, and prelight tags specify the images to use as + follows: +<screen> +<normal file="picture.png" tint="#dddddd"/> +</screen> + </para> + + <para> + Note that relative pathnames are assumed to be in the same + directory as the theme <filename>.xml</filename> file in + <filename><share>/gdm/themes/<theme_name></filename>. + </para> + + <para> + Note that alternative image file can be specified using the altfile[n] + property. GDM will use the last valid image filename specified. + For example: +<screen> +<normal file="picture.png" altfile1="distribution-blah-image.png" altfile2="distribution-foo-image.png"/> +</screen> + If <filename>distribution-foo-image.png</filename> is a valid image + filename it will be used. Otherwise distribution-blah-image.png will + be used if valid. This feature supported since 2.16.3. + </para> + + </sect3> + + <sect3 id="listcoloronodes"> + <title>Face Browser Icon/Label Color Nodes</title> + + <para> + If the item type is of userlist, then the background color for the + icon and label can be set separately via the the following tag: + </para> + + <para> +<screen> +<color iconcolor="#dddddd" labelcolor="#ffffff"/> +</screen> + </para> + </sect3> + + <sect3 id="textnodes"> + <title>Text Node</title> + + <para> + Text tags are used by labels. They can be used to display + localized text as follows (if the "xml:lang" attribute is + omitted, the C locale is assumed): +<screen> +<text xml:lang="fr">Option</text> +</screen> + </para> + + <para> + You can include pango markup in the text nodes for labels, however + you must encode it. So for example to have the label of + "foo<sup>bar</sup>", you must type: +<screen> +<text>"foo<sup>bar</sup>"</text> +</screen> + </para> + + <para> + Text nodes can contain the following special character sequences + which will be translated as follows: + </para> + + <para> + %% - A literal % character + </para> + <para> + %c - Clock time. Only labels with the "clock" id will + update automatically every second. Other labels will contain a + static timestamp. + </para> + <para> + %d - Display name (DISPLAY environment variable) + </para> + <para> + %h - Hostname (gethostname output) + </para> + <para> + %m - Machine name (uname.machine output) + </para> + <para> + %n - Node name (uname.nodename output) + </para> + <para> + %o - Domain name (getdomainname output) + </para> + <para> + %r - Release name (uname.release output) + </para> + <para> + %s - System name (uname.sysname output) + </para> + <para> + %t - Current timed delay value from configuration file (0 if off) + followed by the word "seconds" if value is greater than 1 + or the word "second" if the value is 1. This character + sequence is intended to be only used internally to display the + "timed-label" message, which is automatically updated every + second. + </para> + <para> + %u - Timed username value from configuration file (empty if off) + This character sequence is intended to be only used internally to + display the "timed-label" message, which is automatically + updated every second. + </para> + <para> + \n - Carriage return + </para> + <para> + _ - An underscore causes the following character to be underlined. + If it precedes a % character sequence, the string that replaces the + character sequence is underlined. + </para> + </sect3> + + <sect3 id="stocklabels"> + <title>Stock</title> + + <para> + Certain common localized labels can be specified via the stock + tags. The "text" tag is ignored if the "stock" + tag is used. You should really use the stock labels rather then + just putting all the translations into the themes. This gives + faster load times and likely better translations. The following + values are valid: + </para> + + <para> + <filename>cancel</filename>, _("_Cancel" + </para> + <para> + <filename>caps-lock-warning</filename>, + _("Caps Lock key is on." + </para> + <para> + <filename>chooser</filename>, _("Remote Login via _XDMCP" + </para> + <para> + <filename>config</filename>, _("_Configure" + </para> + <para> + <filename>custom_cmd[0-9]</filename>, _("Custom_[0-9]" + </para> + <para> + <filename>disconnect</filename>, _("D_isconnect" + </para> + <para> + <filename>halt</filename>, _("Shut _Down" + </para> + <para> + <filename>language</filename>, _("_Language" + </para> + <para> + <filename>ok</filename>, _("_OK" + </para> + <para> + <filename>quit</filename>, _("_Quit" + </para> + <para> + <filename>reboot</filename>, _("_Restart" + </para> + <para> + <filename>session</filename>, _("_Session" + </para> + <para> + <filename>startover</filename>, _("_Start Over" + </para> + <para> + <filename>suspend</filename>, _("Sus_pend" + </para> + <para> + <filename>system</filename>, _("_Actions" + (Formerly "S_ystem" + </para> + <para> + <filename>timed-label</filename>, + _("User %u will login in %t" + </para> + <para> + <filename>username-label</filename>, _("Username:" + </para> + <para> + <filename>welcome-label</filename>, _("Welcome to %n" + </para> + + <para> + For example: +<screen> +<stock type="welcome-label"> +</screen> + </para> + </sect3> + + <sect3 id="customwidgetry"> + <title>Custom Widgetry</title> + + <para> + Currently there is one item which is customizable and this is + the list item. If you need to ask the user extra things, such as + to pick from a list of places to log into, or set of custom login + sessions you can setup the list item and add listitem children that + describe the choices. Each listitem must have an id and a text + child. The choice will be recorded in the file + <filename><ServAuthDir>/<display>.GreeterInfo</filename> + as <filename><list id>=<listitem id></filename>. + </para> + + <para> + For example suppose we are on display :0, + <filename>ServAuthDir</filename> is + <filename><var>/lib/gdm</filename> and we have the following in the + theme: + </para> + +<screen> +<item type="list" id="custom-config"> +<pos anchor="nw" x="1" y="1" height="200" width="100"> +<listitem id="foo"> +<text>Foo</text> +</listitem> +<listitem id="bar"> +<text>Bar</text> +</listitem> +</item> +</screen> + + <para> + Then if the user chooses 'Foo' then + <filename><var>/lib/gdm/:0.GreeterInfo</filename> will contain: +<screen> +custom-config=foo +</screen> + </para> + </sect3> + </sect2> + </sect1> + + <sect1 id="accessibility"> + <title>Accessibility</title> + <para> + GDM supports "Accessible Login", allowing users to log into + their desktop session even if they cannot easily use the screen, mouse, + or keyboard in the usual way. Accessible Technology (AT) programs + such as <command>GOK</command> (on-screen keyboard) and + <command>orca</command> (magnifier and text-to-speech) are supported. + The "GTK+ Greeter" best supports accessibility, so it is + recommended for accessibility support. The "Themed Greeter" + supports some accessibility features and may be usable by some users. + But some AT programs, such as <command>GOK</command>, do not yet work + with the "Themed Greeter". + </para> + + <para> + Accessibility is enabled by specifying the "GTK+ Greeter" + in the "Local" tab for the console display and specifying + the "GTK+ Greeter" in the "Remote" tab for + remote displays. Or you can modify the <filename>Greeter</filename> + and <filename>RemoteGreeter</filename> configuration options by hand + to be <command>/usr/lib/gdmlogin</command>. + </para> + + <para> + The GDM greeter programs support the ability to launch AT's at login + time via configurable "gestures". These gestures can be + defined to be standard keyboard hotkeys, switch device event, or + mouse motion events. When using the "GTK+ Greeter", the + user may also change the visual appearance of the login UI. For + example, to use a higher-contrast color scheme for better visibility. + </para> + + <para> + Note that <command>gdmsetup</command> does not yet work with + accessibility, so that users who require AT programs should only + configure GDM by editing the ASCII files directly. + </para> + + <sect2 id="accessibilityconfig"> + <title>Accessibility Configuration</title> + + <para> + In order to enable Accessible Login, the system administrator must + make some changes to the default login configuration by manually + modifying three human-readable configuration files, stored in + the GDM Custom Configuration File, AccessKeyMouseEvents File, and + AccessDwellMouseEvents File. The AccessKeyMouseEvents and + AccessDwellMouseEvents contain reasonable default gestures for + launching <command>GOK</command> and <command>orca</command>, but + some users may require these gestures to be configured to best + meet their needs. For example, shorter or longer duration for + holding down a button or hotkey might make the login experience + more usable for some users. Also, additional AT programs may be + added to the configuration file if needed. + </para> + + <sect3 id="accessibilitytheming"> + <title>Accessibile Theming</title> + + <para> + If using the "GTK+ Greeter" users can easily + switch the color and contrast scheme of the dialog. To do this, + ensure the <filename>AllowGtkThemeChange</filename> parameter in + the GDM configuration is set to "true". This should + be the default value. When true, the "Standard + Greeter" contains a menu allowing the user to change to a + different GTK+ theme. The <filename>GtkThemesToAllow</filename> + configuration choice can also be used to limit the choices + available as desired. For example: + </para> + +<screen> +GtkThemesToAllow=HighContrast,HighContrastInverse +</screen> + + <para> + If using the "Themed Greeter" there may be suitable + GDM themes available that provide needed color and contrast + schemes, but these are not yet shipped with the GDM program. + Some distributions may ship such themes. There is not yet any + mechanism to switch between themes in the "Themed + Greeter", so if an accessible theme is required by one + user, then all users would need to use the same theme. + </para> + </sect3> + + <sect3 id="accessibilityatprograms"> + <title>AT Program Support</title> + + <para> + To enable user to launch AT such as the <command>GOK</command> + or <command>orca</command>, the + <filename>AddGtkModules</filename> parameter in the GDM + configuration must be set to "true". + Also the <filename>GtkModulesList</filename> parameter must be + uncommented and set as follows: + </para> + +<screen> +GtkModulesList=gail:atk-bridge:/usr/lib/gtk-2.0/modules/libdwellmouselistener:/usr/lib/gtk-2.0/modules/libkeymouselistener +</screen> + + <para> + This causes all GDM GUI programs to be run with the appropriate + GTK modules for launching AT programs. The use of assistive + technologies and the atk-bridge module requires the registry + daemon, <command>at-spi-registryd</command>, to be running. + This is handled by the GDM GUI starting with version 2.17. + </para> + + <para> + System administrators may wish to load only the minimum subset + of these modules which is required to support their user base. + The "libkeymouselistener" provides hotkey and switch + gesture support while the "libdwellmouselistener" + provides mouse motion gesture support. If your user base only + requires one or the other, it is only necessary to include the + gesture listener that is needed. Also, some AT programs may not + require gail or atk-bridge. If you find the AT programs you + need works fine without including these, then they may be + omitted. Note that some AT programs work with a reduced feature + set if gail and/or atk-bridge are not present. However, for + general accessibility use, including all four is suitable. + </para> + + <para> + Once "keymouselistener" and/or + "dwellmouselistener" have been added to the + <filename>AddGtkModules</filename> loaded by GDM, then you may + need to modiify the gesture configurations to meet your user's + needs. Default gestures are provided for launching + <command>GOK</command> and <command>orca</command>, but it is + recommended to modify these gestures so they work best for your + user base. These gesture associations are contained in files + <filename>AccessKeyMouseEvents</filename> and + <filename>AccessDwellMouseEvents</filename>, respectively. Both + files are located in the + <filename><etc>/gdm/modules</filename> directory. The + gesture configuration format is described in the comment section + of the two configuration files. + </para> + + <para> + The AccessKeyMouseEvents file controls the keymouselistener + Gesture Listener and is used to define key-press, mouse button, + or XInput device sequences that can be used to launch + applications needed for accessibility. In order to reduce the + likelihood of unintentional launch, these "gestures" + may be associated with multiple switch presses and/or minimum + durations. Note that the XKB extension is needed for key + gestures to work, so you may need to add +xkb to your X server + command line for gestures to work properly. The X server command + line is specified in the GDM configuration file in the + "server-foo" sections. + </para> + + <para> + The DwellKeyMouseEvents file controls the dwellmouselistner and + supports gestures that involve the motion of a pointing device + such as the system mouse of an alternative pointing device such + as a head pointer or trackball may also be defined. Motion + gestures are defined as "crossing events" into and out + of the login dialog window. If the + "dwellmouselistener" gesture listener is loaded, then + alternative pointing devices are temporarily "latched" + to the core pointer, such that motion from alternative devices + results in movement of the onscreen pointer. All gestures are + specified by the same syntax; that is, there is no distinction + between a "core mouse" gesture and motion from an + alternate input device. + </para> + + <para> + On some operating systems, it is necessary to make sure that the + GDM user is a member of the "audio" group for AT + programs that require audio output (such as text-to-speech) to + be functional. + </para> + + <para> + Currently GDM does not remember what accessible technology + programs have been started when switching applications. So if + the user switches between the login program and the chooser, for + example, then it is necessary for the user to redo the gesture. + Users may need to also set up their default session so that the + assistive technologies required are started automatically (or + have appropriate key-bindings defined to start them) after the + user session has started. + </para> + </sect3> + + <sect3 id="accessibilitytroubleshooting"> + <title>AT Troubleshooting</title> + + <para> + There are some common issues that cause users to have problems + getting the gesture listeners to work. It is recommended that + people use GDM version 2.18.0 or later for best results. + </para> + + <para> + Some older X servers have a bug which causes detectable + autorepeat to fail when XEVIE is enabled (which happens when + atk-bridge is included as a GTK Module). This bug causes key + gestures with a duration greater than 0 to always fail. A + workaround is to simply redefine all key gestures so they have + zero length duration, or upgrade your X server. + </para> + + <para> + Some versions of <command>GOK</command> and + <command>orca</command> will not launch unless the + "gdm" user has a writable home directory. This has + been fixed in GNOME 2.18, but if using an older version of + GNOME, then making sure that the GDM user has a writable home + directory should make these programs functional. + </para> + + <para> + If you see an hourglass cursor when you complete a gesture but + the program does not start, then this indicates that the gesture + was received, but that there was a problem starting the program. + Most likely the issue may be the lack of a writable gdm home + directory. + </para> + + <para> + Also note that some input devices require X server configuration + before GDM will recognize them. + </para> + </sect3> + + <sect3 id="accessibilitysound"> + <title>Accessibility Login Sound Configuration</title> + + <para> + By default, GDM requires a media application such as + "play" to be present to play sounds for successful or + failed login. GDM defaults + the location of this application to + <filename><bin>/play</filename> (or + <filename><bin>/audioplay</filename> on Solaris. This can + be changed via the <filename>SoundProgram</filename> GDM + configuration option. Typically most text-to-speech programs + (such as <command>orca</command>) use a separate mechanism to + play audio, so this configuration setting is not needed for + them to work. + </para> + </sect3> + </sect2> + </sect1> + + <sect1 id="solaris"> + <title>Solaris Specific Features</title> + + <sect2 id="solarisusing"> + <title>Using GDM on Solaris</title> + + <para> + GDM is not yet the default login program on Solaris. If you wish + to switch to using GDM, then you need to turn off CDE login and + start the GDM service. Note that turning off or disabiling CDE + login will cause any running sessions to immediately exit, and any + unsaved data will be lost. Only run these commands if you are + sure there is no unsaved data in your running sessions. It would + be best to run these commands from console login, or a Failsafe + Terminal rather than from a running GUI session. The first step + is to run the following command to see if CDE login is running as + an SMF service. + </para> + +<screen> +svcs cde-login +</screen> + + <para> + If the <command>svcs</command> command responds that this + service is enabled, then run this command to disable CDE login: + </para> + +<screen> +svcadm disable cde-login +</screen> + + <para> + If the <command>svcs</command> command responds that this pattern + doesn't match any instances, then run these commands to stop + CDE login: + </para> + +<screen> +/usr/dt/config/dtconfig -d +Either reboot, or kill any running dtlogin processes. +</screen> + + <para> + At this point you will be presented with a console login. Login + as root, and run the following command. If on Solaris 10 the + servicename is "gdm2-login", if on Solaris Nevada the + servicename is "gdm". + </para> + +<screen> +svcadm enable servicename +</screen> + </sect2> + + <sect2 id="solarisconfiguration"> + <title>Solaris Configuration</title> + <para> + On Solaris, the following configuration is recommended. + This turns on IPv6 and also turns on PreFetch for + performance benefit. + +<screen> +./autogen.sh --prefix=/usr --sysconfdir=/etc/X11 --localstatedir=/var + --libexecdir=/usr/lib --enable-ipv6=yes --with-at-bindir=/usr/sfw/bin + --with-prefetch --with-post-path=/usr/openwin/bin --with-pam-prefix=/etc + --with-lang-file=/etc/default/init +</screen> + </para> + + <para> + Configuring GDM with the + "--with-post-path=/usr/openwin/bin" on Solaris is + recommended for accessing X server programs. + </para> + </sect2> + + <sect2 id="solarislogindevperm"> + <title>Solaris /etc/logindevperm</title> + <para> + GDM supports /etc/logindevperm, but only on Solaris 10 and + higher. Refer to the logindevperm.4 man page for more + information. + </para> + + <para> + To make /etc/logindevperm functionality work on Solaris 9 or + earlier you would have to hack the GDM PreSession and + PostSession script to chmod the device permissions directly. In + other words, if /etc/logindevperm had a listing like this: + </para> + +<screen> +/dev/console 0600 /dev/sound/* # audio devices +</screen> + + <para> + Then the PreSession script would need to be modified to chown + /dev/console to the user:group who is logging into the console + and ensure whatever permissions is specified in /etc/logindevperm + (0600 for the line above). Then in the PostSession script chmod + the device back to root:root and ensure 0600 this time (do not + use the value in the /etc/logindevperm file). Linux uses a + different mechanism for managing device permissions, so this + extra scripting is not needed. + </para> + </sect2> + + <sect2 id="solarisautomaticlogin"> + <title>Solaris Automatic Login</title> + <para> + Automatic login does not work on Solaris 10 and earlier because + PAM is not configured to support this feature by default. + Automatic login is a GDM feature that is not enabled by default, + so you would only notice this problem if you try to make use of + it. Turning this feature on causes your computer to login to a + specified username on startup without asking for username + and password. This is an insecure way to set up your + computer. + </para> + + <para> + If using Solaris 10 or lower, then you need to compile the + pam_allow.c code provided with the GDM release and install it + to /usr/lib/security (or provide the full path in /etc/pam.conf) + and ensure it is owned by uid 0 and not group or world writable. + </para> + + <para> + The following are reasonable pam.conf values for turning on + automatic login in GDM. Make sure to read the PAM documentation + (e.g. pam.d/pam.conf man page) and be comfortable with the + security implications of any changes you intend to make to + your configuration. + </para> + +<screen> + gdm-autologin auth required pam_unix_cred.so.1 + gdm-autologin auth sufficient pam_allow.so.1 + gdm-autologin account sufficient pam_allow.so.1 + gdm-autologin session sufficient pam_allow.so.1 + gdm-autologin password sufficient pam_allow.so.1 +</screen> + + <para> + The above setup will cause no lastlog entry to be generated. If + a lastlog entry is desired, then use the following for session: + </para> + +<screen> + gdm-autologin session required pam_unix_session.so.1 +</screen> + </sect2> + + <sect2 id="solarisrbac"> + <title>Solaris RBAC support for Shutdown, Reboot, and Suspend</title> + + <para> + Starting with GDM 2.19, GDM supports RBAC (Role Based + Access Control) for enabling the system commands (Shutdown, + Reboot, Suspend, etc.) that appear in the greeter system + menu and via the <command>gdmflexiserver</command> + QUERY_LOGOUT_ACTION, SET_LOGOUT_ACTION, and + SET_SAFE_LOGOUT_ACTION commands. + </para> + + <para> + On Solaris GDM has the following value specified for the + <filename>RBACSystemCommandKeys</filename> configuration + option. + </para> + +<screen> +HALT:solaris.system.shutdown;REBOOT:solaris.system.shutdown +</screen> + + <para> + This will cause the SHUTDOWN and REBOOT features to only be + enabled for users who have RBAC authority. In other words, + those users who have the "solaris.system.shutdown" + authorization name specified. The GDM greeter will only + display these options if the gdm user (specified in the + <filename>User</filename> configuration option, "gdm" by + default) has such RBAC permissions. + </para> + + <para> + Therefore, add the "solaris.system.shutdown" + authorization name to the <filename>/etc/user_attr</filename> + for all users who should have authority to shutdown and + reboot the system. If you want these options to appear in + the greeter program, also add this authorization name to + the gdm user. If you don't want to use RBAC, then you may + unset the <filename>RBACSystemCommandKeys</filename> GDM + configuration key, and this will make the system commands + available for all users. Refer to the + <filename>user_attr</filename> man page for more information + about setting RBAC privileges. + </para> + + <para> + Note that on Solaris there are two programs that can be used + to shutdown the system. These are GDM and + <command>gnome-sys-suspend</command>. + <command>gnome-sys-suspend</command> is a GUI front-end for + the <command>sys-suspend</command>. + </para> + + <para> + If GDM is being used as the login program and the user has + RBAC permissions to shutdown the machine (or RBAC support + is disabled in GDM), then the GNOME panel + "Shut Down.." option will use GDM to shutdown, reboot, + and suspend the machine. This is a bit nicer than using + <command>gnome-sys-suspend</command> since GDM will wait until + the user session has finished (including running the + PostSession script, etc.) before running the + shutdown/reboot/suspend command. Also the + <command>gnome-sys-suspend</command> command is less functional + since it does not support a reboot option, only shutdown and + suspend. + </para> + + <para> + If GDM is not being used to manage shutdown, reboot, and + suspend; then the GNOME panel uses + <command>gnome-sys-suspend</command> when you select the + "Shut Down..." option from the application menu. + If the pop-up that appears when you select this only + shows the suspend and shutdown options, then you are + likely using <command>gnome-sys-suspend</command>. If + you are using this, then refer to the + <command>sys-suspend</command> man page for information + about how to configure it. Or consider using GDM and + configuring it to provide these options. + </para> + </sect2> + + <sect2 id="solarisother"> + <title>Other Solaris Features</title> + <para> + GDM supports a few features specific to Solaris, as follows: + </para> + + <para> + GDM supports Solaris Auditing if running on Solaris 10 or + higher. GDM should not be used if auditing is needed and + running Solaris 9 or older. + </para> + + <para> + GDM supports a security feature which causes the X server to + run as the user instead of as the root user. GDM must be using + PAM for this feature to be enabled, which is the normal case + for Solaris. This second feature has the side-effect of + causing the X server to always restart between sessions, which + disables the AlwaysRestartServer configuration option. + </para> + + <para> + Solaris supports the <filename>/etc/default/login</filename> + interface, which affects the <filename>DefaultPath</filename>, + <filename>RootPath</filename>, + <filename>PasswordRequired</filename>, and + <filename>AllowRemoteRoot</filename> options as described in the + "Configuration" section. + </para> + </sect2> + </sect1> + + <sect1 id="exampleconf"> + <title>Example Configurations</title> + + <para> + This section has some example configurations that are useful for + various setups. + </para> + + <sect2 id="terminallab"> + <title>Terminal Lab With One Server</title> + + <para> + Suppose you want to make a lab full of X terminals that all connect + to one server machine. So let's call one X terminal + <filename>xterminal</filename> and let's call the server machine + <filename>appserver</filename>. You install GDM on both. + </para> + + <para> + On <filename>appserver</filename> you enable XDMCP, so you have +<screen> +[xdmcp] +Enable=true +</screen> + If you want no local screens here, you can then + make the <filename>[servers]</filename> section empty. + </para> + + <para> + On the <filename>xterminal</filename> you disable XDMCP (you don't + want anyone to connect to the xterminal really). You will add a + server type perhaps called <filename>Terminal</filename> as follows: +<screen> +[server-Terminal] +name=Terminal server +command=/path/to/X -terminate +flexible=false +handled=false +</screen> + This definition should in fact be included in the standard + configuration file. Notice that we made the + <filename>handled</filename> key false since we don't want GDM to + handle this server localy. Also note that we have not yet added the + <filename>-query</filename> argument, you can add that here, or in the + <filename>[servers]</filename> section. We'll define our local + servers as follows: +<screen> +[servers] +0=Terminal -query appserver +</screen> + This will run a direct XDMCP query to the server named + <filename>appserver</filename>. + </para> + </sect2> + + <sect2 id="terminallabtwo"> + <title>Terminal Lab With Two Or More Servers</title> + + <para> + Suppose you want to make a lab full of X terminals that all connect + to some choice of servers. For now let's make it + <filename>appserverone</filename> and + <filename>appservertwo</filename>. Again we'll call our example X + terminal server <filename>xterminal</filename>. The setup on both + servers is the same as with the case of one server in the previous + section. You do not need to explicitly enable indirect queries on the + server since we'll run the choosers locally on the X terminals. + </para> + + <para> + So on the <filename>xterminal</filename> you again disable XDMCP. + You will add a server type perhaps called <filename>Chooser</filename> + as follows: +<screen> +[server-Chooser] +name=Chooser server +command=/path/to/X +flexible=false +chooser=true +</screen> + And again this definition should in fact be included in the standard + configuration file. Notice that we made the + <filename>chooser</filename> key true here. This will run the XDMCP + chooser for this server, and when the user chooses a host GDM will run + a query for that host. Then we will define our local servers as + follows: +<screen> +[servers] +0=Chooser +</screen> + </para> + + <para> + The XDMCP chooser on the X terminal will normally give a broadcast + query to see which servers exist on the network. If the two servers + are not reachable by a broadcast query, you must add them by hand to + the configuration file. So in the <filename>[chooser]</filename> + section you would have: +<screen> +Hosts=appserverone,appservertwo +</screen> + and any other servers you wish the users to be able to connect to. + </para> + + <para> + Sometimes you may want to run the chooser on the server side however. + Then what you want to do is to run a configuration similar to the + previous section about the one server configuration with XDMCP + indirect queries enabled on <filename>appserver</filename> and on the + X terminals you'd have +<screen> +[servers] +0=Terminal -indirect appserver +</screen> + This way for example you only have to maintain one + <filename>Hosts</filename> entry. However as a disadvantage then, + the <filename>appserver</filename> must then always be available. So + it's not good for situations where you want to have several servers + and not all of them have to be on all the time. You could also have + one of the X terminals handle indirect XDMCP queries and serve up the + chooser to the other X terminals. + </para> + </sect2> + + <sect2 id="customcommand"> + <title>Defining Custom Commands</title> + + <para> + Suppose you want to add a custom command to the GDM menu that will give + you the oportunity to boot into other operating system such as Windoze. + Jsut add the following options into the + <filename>[customcommand]</filename> section of the GDM configuration + file. + + <screen> + [customcommand] + CustomCommand0=/sbin/rebootwindoze;/usr/local/sbin/rebootwindoze + CustomCommandLabel0=_Windoze + CustomCommandLRLabel0=Reboot into _Windoze + CustomCommandText0=Are you sure you want to restart the computer into Windoze? + CustomCommandTooltip0=Restarts the computer into Windoze + CustomCommandIsPersistent0=true + </screen> + + CustomCommand0 specifies two commands separated by a semicolon: + <filename>/sbin/rebootwindoze</filename> and + <filename>/usr/local/sbin/rebootwindoze</filename>. GDM will use + the first valid command in the list. This allows different + commands for different operating systems to be included. + </para> + <para> + Note, that besides being able to customise this option to reboot into + different operating systems you can also use it to define your own + custom behaviours that you wish to run from the GDM menu. Suppose you + want to give users the oportunity to run system update scripts from the + login screen. Add the following options into the + <filename>[customcommand]</filename> section of your GDM configuration + file. + + <screen> + [customcommand] + CustomCommand0=/sbin/updatesystem;/usr/local/sbin/updatesystem + CustomCommandLabel0=_Update Me + CustomCommandLRLabel0=Update the system + CustomCommandText0=Are you sure you want to update the system software? + CustomCommandTooltip0=Updates the system + CustomCommandNoRestart0=true + </screen> + </para> + + <para> + Both custom commands could be defined as follows. + + <screen> + [customcommand] + CustomCommand0=/sbin/rebootwindoze;/usr/local/sbin/rebootwindoze + CustomCommandLabel0=_Windoze + CustomCommandLRLabel0=Reboot into _Windoze + CustomCommandText0=Are you sure you want to restart the computer into Windoze? + CustomCommandTooltip0=Restarts the computer into Windoze + CustomCommandIsPersistent0=true + + CustomCommand1=/sbin/updatesystem;/usr/local/sbin/updatesystem + CustomCommandLabel1=_Update Me + CustomCommandLRLabel1=Update the system + CustomCommandText1=Are you sure you want to update the system software? + CustomCommandTooltip1=Updates the system + CustomCommandNoRestart1=true + </screen> + </para> + + <para> + There can be up to 10 custom commands numbered 0-9. + + <screen> + [customcommand] + CustomCommand0=/sbin/rebootwindoze;/usr/local/sbin/rebootwindoze + CustomCommandLabel0=_Windoze + CustomCommandLRLabel0=Reboot into _Windoze + CustomCommandText0=Are you sure you want to restart the computer into Windoze? + CustomCommandTooltip0=Restarts the computer into Windoze + CustomCommandIsPersistent0=true + + CustomCommand1=/sbin/updatesystem;/usr/local/sbin/updatesystem + CustomCommandLabel1=_Update Me + CustomCommandLRLabel1=Update the system + CustomCommandText1=Are you sure you want to update the system software? + CustomCommandTooltip1=Updates the system + CustomCommandNoRestart1=true + + CustomCommand3=/sbin/do_something + . + . + . + + CustomCommand4=/sbin/do_something_else + . + . + . + </screen> + </para> + </sect2> + </sect1> + + <sect1 id="troubleshooting"> + <title>Troubleshooting</title> + + <para> + This section discusses helpful tips for getting GDM working. In general, + if you have a problem using GDM, you can submit a bug to the + "gdm" category in + <ulink type="http" url="http://bugzilla.gnome.org/">bugzilla.gnome.org</ulink> + or send an email to the + <address><email>gdm-list@gnome.org</email></address> mail list. + </para> + + <para> + If GDM is failing to work properly, it is always a good idea to include + debug information. Use the <command>gdmsetup</command> command to turn + on debug ("Enable debug messages to system log" checkbox in the + "Security" tab), then use GDM to the point where it fails, and + include the GDM output sent to your system log + (<filename><var>/log/messages</filename> or + <filename><var>/adm/messages</filename> depending on your operating + system). Since the system log can be large, please only include the GDM + debug information and do not sent the entire file. If you do not see any + GDM syslog output, you may need to configure syslog (see syslog.3c man + page). + </para> + + <para> + You should not leave debug on after collecting data. It will clutter your + syslog and slow system performance. + </para> + + <sect2 id="wontstart"> + <title>GDM Will Not Start</title> + + <para> + There are a many problems that can cause GDM to fail to start, but + this section will discuss a few common problems and how to approach + tracking down a problem with GDM starting. Some problems will + cause GDM to respond with an error message or dialog when it tries + to start, but it can be difficult to track down problems when GDM + fails silently. + </para> + + <para> + First make sure that the X server is configured properly. The + GDM configuration file contains a command in the [server-Standard] + section that is used for starting the X server. Verify that this + command works on your system. Running this command from the + console should start the X server. If it fails, then the problem + is likely with your X server configuration. Refer to your X server + error log for an idea of what the problem may be. The problem may + also be that your X server requires different command-line options. + If so, then modify the X server command in the GDM configuration file + so that it is correct for your system. + </para> + + <para> + Another common problem is that the GDM greeter program is having + trouble starting. This can happen, for example, if GDM cannot find + a needed library or other resource. Try starting the X server and + a terminal program, set the shell environment variable + DOING_GDM_DEVELOPMENT=1 and run + <command><lib>/gdmlogin</command> + or <command><lib>/gdmgreeter</command>. Any error messages + echoed to the terminal will likely highlight the problem. Also, + turning on debug and checking the output sent to the system log + will often highlight the problem. + </para> + + <para> + Also make sure that the <filename>/tmp</filename> directory has + reasonable ownership and permissions, and that the machine's file + system is not full. These problems will cause GDM to fail to start. + </para> + </sect2> + + <sect2 id="notaccessfile"> + <title>GDM Will Not Access User Settings</title> + + <para> + GDM saves user settings, such as your default session and default + language, in the <filename>~/.dmrc</filename>. Other files, such + as the user's <filename>~/.Xauthority</filename> file will also + affect login. GDM, by default, is strict about how it tries to + access files in the user's home directory, and will ignore the file if + they do not conform to certain rules. You can use the + <filename>RelaxPermissions</filename> configuration option to + make GDM less strict about how it accesses files in the user's + home directory, or correct the permissions issues that cause GDM + to ignore the file. This is discussed in detail described in the + "File Access" section of the "Overview". + </para> + </sect2> + </sect1> + + <!-- ============= Application License ============================= --> + + <sect1 id="license"> + <title>License</title> + <para> + This program is free software; you can redistribute it and/or + modify it under the terms of the <ulink type="help" url="gnome-help:gpl"> + <citetitle>GNU General Public License</citetitle></ulink> as + published by the Free Software Foundation; + either version 2 of the License, or (at your option) any later + version. + </para> + <para> + This program is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + <citetitle>GNU General Public License</citetitle> for more details. + </para> + <para> + A copy of the <citetitle>GNU General Public License</citetitle> is + included as an appendix to the <citetitle>GNOME Users + Guide</citetitle>. You may also obtain a copy of the + <citetitle>GNU General Public License</citetitle> from the Free + Software Foundation by visiting <ulink type="http" url="http://www.fsf.org">their Web site</ulink> or by writing to + <address> + Free Software Foundation, Inc. + <street>59 Temple Place</street> - Suite 330 + <city>Boston</city>, <state>MA</state> <postcode>02111-1307</postcode> + <country>USA</country> + </address> + </para> + </sect1> +</article> +<!-- Keep this comment at the end of the file +Local variables: +mode: sgml +sgml-omittag:t +sgml-shorttag:t +sgml-minimize-attributes:nil +sgml-always-quote-attributes:t +sgml-indent-step:2 +sgml-indent-data:t +sgml-parent-document:nil +sgml-exposed-tags:nil +sgml-local-catalogs:nil +sgml-local-ecat-files:nil +End: +--> |