Add method to QDBusServer to allow anonymous client connections.

This change adds a new method to QDBusServer to allow anonymous
connections. This is part of the DBus API and was not yet possible
to use with QDBusServer. It is set in the newConnection callback
when a new client tries to connect.
Anonymous connections are enabled by default in DBus but not allowed
by default.

[ChangeLog][QtDBus][QDBusServer] Added method to QDBusServer to allow
anonymous client connections, even if the connecting client is not
authenticated as a user.

Change-Id: I984c9e634101ecd2e67bb25c8d12bb1071836fd3
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/dbus/qdbus_symbols_p.h

@@ -183,6 +183,9 @@ DEFINEFUNC(unsigned int , dbus_watch_get_flags, (DBusWatch        *watch),
 DEFINEFUNC(dbus_bool_t  , dbus_watch_handle, (DBusWatch        *watch,
                                               unsigned int      flags),
            (watch, flags), return)
+DEFINEFUNC(void         , dbus_connection_set_allow_anonymous, (DBusConnection             *connection,
+                                                                dbus_bool_t                 value),
+           (connection, value), return)
 
 /* dbus-errors.h */
 DEFINEFUNC(void        , dbus_error_free, (DBusError       *error),

src/dbus/qdbusconnection_p.h

@@ -322,6 +322,8 @@ public:
     QMutex callDeliveryMutex;
     QDBusCallDeliveryEvent *callDeliveryState; // protected by the callDeliveryMutex mutex
 
+    bool anonymousAuthenticationAllowed;
+
 public:
     // static methods
     static int findSlot(QObject *obj, const QByteArray &normalizedName, QVector<int> &params);

src/dbus/qdbusintegrator.cpp

@@ -391,6 +391,10 @@ static void qDBusNewConnection(DBusServer *server, DBusConnection *connection, v
     q_dbus_connection_ref(connection);
     QDBusConnectionPrivate *serverConnection = static_cast<QDBusConnectionPrivate *>(data);
 
+    // allow anonymous authentication
+    if (serverConnection->anonymousAuthenticationAllowed)
+        q_dbus_connection_set_allow_anonymous(connection, true);
+
     QDBusConnectionPrivate *newConnection = new QDBusConnectionPrivate(serverConnection->parent());
     QMutexLocker locker(&QDBusConnectionManager::instance()->mutex);
     QDBusConnectionManager::instance()->setConnection(QLatin1String("QDBusServer-") + QString::number(reinterpret_cast<qulonglong>(newConnection)), newConnection);
@@ -1014,7 +1018,8 @@ extern bool qDBusInitThreads();
 QDBusConnectionPrivate::QDBusConnectionPrivate(QObject *p)
     : QObject(p), ref(1), capabilities(0), mode(InvalidMode), connection(0), server(0), busService(0),
       watchAndTimeoutLock(QMutex::Recursive),
-      rootNode(QString(QLatin1Char('/')))
+      rootNode(QString(QLatin1Char('/'))),
+      anonymousAuthenticationAllowed(false)
 {
     static const bool threads = q_dbus_threads_init_default();
     static const int debugging = qgetenv("QDBUS_DEBUG").toInt();

src/dbus/qdbusserver.cpp

@@ -149,6 +149,33 @@ QString QDBusServer::address() const
     return addr;
 }
 
+/*!
+    \since 5.3
+
+    If \a value is set to true, an incoming connection can proceed even if the
+    connecting client is not authenticated as a user.
+
+    By default, this value is false.
+
+    \sa isAnonymousAuthenticationAllowed()
+*/
+void QDBusServer::setAnonymousAuthenticationAllowed(bool value)
+{
+    d->anonymousAuthenticationAllowed = value;
+}
+
+/*!
+    \since 5.3
+
+    Returns true if anonymous authentication is allowed.
+
+    \sa setAnonymousAuthenticationAllowed()
+*/
+bool QDBusServer::isAnonymousAuthenticationAllowed() const
+{
+    return d->anonymousAuthenticationAllowed;
+}
+
 /*!
   \fn void QDBusServer::newConnection(const QDBusConnection &connection)
 

src/dbus/qdbusserver.h

@@ -66,6 +66,9 @@ public:
     QDBusError lastError() const;
     QString address() const;
 
+    void setAnonymousAuthenticationAllowed(bool value);
+    bool isAnonymousAuthenticationAllowed() const;
+
 Q_SIGNALS:
     void newConnection(const QDBusConnection &connection);