dbus: add 'scanning' property

When the supplicant is connected and performs a scan, it doesn't enter
WPA_SCANNING state for various reasons.  However, external programs
still need to know that the supplicant is scanning since they may not
wish to perform certain operations during a scan (as those operations
will likely fail or yield incorrect results).  Add a 'scanning' property
and signal to the supplicant dbus interface to allow clients to
synchronize better with the supplicant when it scans.

Signed-off-by: Dan Williams <dcbw@redhat.com>

wpa_supplicant/ctrl_iface_dbus.c

@@ -541,6 +541,8 @@ static DBusHandlerResult wpas_iface_message_handler(DBusConnection *connection,
 								      wpa_s);
 		else if (!strcmp(method, "state"))
 			reply = wpas_dbus_iface_get_state(message, wpa_s);
+		else if (!strcmp(method, "scanning"))
+			reply = wpas_dbus_iface_get_scanning(message, wpa_s);
 		else if (!strcmp(method, "setBlobs"))
 			reply = wpas_dbus_iface_set_blobs(message, wpa_s);
 		else if (!strcmp(method, "removeBlobs"))
@@ -753,6 +755,58 @@ out:
 }
 
 
+/**
+ * wpa_supplicant_dbus_notify_scanning - send scanning status
+ * @wpa_s: %wpa_supplicant network interface data
+ * Returns: 0 on success, -1 on failure
+ *
+ * Notify listeners of interface scanning state changes
+ */
+void wpa_supplicant_dbus_notify_scanning(struct wpa_supplicant *wpa_s)
+{
+	struct ctrl_iface_dbus_priv *iface = wpa_s->global->dbus_ctrl_iface;
+	DBusMessage *_signal;
+	const char *path;
+	dbus_bool_t scanning = wpa_s->scanning ? TRUE : FALSE;
+
+	/* Do nothing if the control interface is not turned on */
+	if (iface == NULL)
+		return;
+
+	path = wpa_supplicant_get_dbus_path(wpa_s);
+	if (path == NULL) {
+		perror("wpa_supplicant_dbus_notify_scanning[dbus]: interface "
+		       "didn't have a dbus path");
+		wpa_printf(MSG_ERROR,
+		           "%s[dbus]: interface didn't have a dbus path; "
+			   "can't send scanning signal.", __FUNCTION__);
+		return;
+	}
+	_signal = dbus_message_new_signal(path, WPAS_DBUS_IFACE_INTERFACE,
+					  "Scanning");
+	if (_signal == NULL) {
+		perror("wpa_supplicant_dbus_notify_scanning[dbus]: couldn't "
+		       "create dbus signal; likely out of memory");
+		wpa_printf(MSG_ERROR, "%s[dbus]: dbus control interface: not "
+		           "enough memory to send scan results signal.",
+		           __FUNCTION__);
+		return;
+	}
+
+	if (dbus_message_append_args(_signal,
+	                             DBUS_TYPE_BOOLEAN, &scanning,
+	                             DBUS_TYPE_INVALID)) {
+		dbus_connection_send(iface->con, _signal, NULL);
+	} else {
+		perror("wpa_supplicant_dbus_notify_scanning[dbus]: not enough "
+		       "memory to construct signal.");
+		wpa_printf(MSG_ERROR, "%s[dbus]: not enough memory to "
+			   "construct signal.", __FUNCTION__);
+	}
+	dbus_message_unref(_signal);
+}
+
+
 #ifdef CONFIG_WPS
 void wpa_supplicant_dbus_notify_wps_cred(struct wpa_supplicant *wpa_s,
 					 const struct wps_credential *cred)

wpa_supplicant/ctrl_iface_dbus.h

@@ -92,6 +92,7 @@ struct ctrl_iface_dbus_priv *
 wpa_supplicant_dbus_ctrl_iface_init(struct wpa_global *global);
 void wpa_supplicant_dbus_ctrl_iface_deinit(struct ctrl_iface_dbus_priv *iface);
 void wpa_supplicant_dbus_notify_scan_results(struct wpa_supplicant *wpa_s);
+void wpa_supplicant_dbus_notify_scanning(struct wpa_supplicant *wpa_s);
 void wpa_supplicant_dbus_notify_state_change(struct wpa_supplicant *wpa_s,
 					     wpa_states new_state,
 					     wpa_states old_state);
@@ -135,6 +136,11 @@ wpa_supplicant_dbus_notify_scan_results(struct wpa_supplicant *wpa_s)
 {
 }
 
+static inline void
+wpa_supplicant_dbus_notify_scanning(struct wpa_supplicant *wpa_s)
+{
+}
+
 static inline void
 wpa_supplicant_dbus_notify_state_change(struct wpa_supplicant *wpa_s,
 					wpa_states new_state,

wpa_supplicant/ctrl_iface_dbus_handlers.c

@@ -1337,6 +1337,35 @@ DBusMessage * wpas_dbus_iface_get_state(DBusMessage *message,
 }
 
 
+/**
+ * wpas_dbus_iface_get_scanning - Get interface scanning state
+ * @message: Pointer to incoming dbus message
+ * @wpa_s: wpa_supplicant structure for a network interface
+ * Returns: A dbus message containing whether the interface is scanning
+ *
+ * Handler function for "scanning" method call.
+ */
+DBusMessage * wpas_dbus_iface_get_scanning(DBusMessage *message,
+					   struct wpa_supplicant *wpa_s)
+{
+	DBusMessage *reply = NULL;
+	dbus_bool_t scanning = wpa_s->scanning ? TRUE : FALSE;
+
+	reply = dbus_message_new_method_return(message);
+	if (reply != NULL) {
+		dbus_message_append_args(reply, DBUS_TYPE_BOOLEAN, &scanning,
+					 DBUS_TYPE_INVALID);
+	} else {
+		perror("wpas_dbus_iface_get_scanning[dbus]: out of "
+		       "memory.");
+		wpa_printf(MSG_ERROR, "dbus control interface: not enough "
+			   "memory to return scanning state.");
+	}
+
+	return reply;
+}
+
+
 /**
  * wpas_dbus_iface_set_blobs - Store named binary blobs (ie, for certificates)
  * @message: Pointer to incoming dbus message

wpa_supplicant/ctrl_iface_dbus_handlers.h

@@ -77,6 +77,9 @@ DBusMessage * wpas_dbus_iface_set_smartcard_modules(
 DBusMessage * wpas_dbus_iface_get_state(DBusMessage *message,
 					struct wpa_supplicant *wpa_s);
 
+DBusMessage * wpas_dbus_iface_get_scanning(DBusMessage *message,
+					   struct wpa_supplicant *wpa_s);
+
 DBusMessage * wpas_dbus_iface_set_blobs(DBusMessage *message,
 				        struct wpa_supplicant *wpa_s);
 

wpa_supplicant/events.c

@@ -615,6 +615,8 @@ static void wpa_supplicant_event_scan_results(struct wpa_supplicant *wpa_s)
 	struct wpa_scan_res *selected = NULL;
 	struct wpa_ssid *ssid = NULL;
 
+	wpa_supplicant_notify_scanning(wpa_s, 0);
+
 	if (wpa_supplicant_get_scan_results(wpa_s) < 0) {
 		if (wpa_s->conf->ap_scan == 2)
 			return;

wpa_supplicant/scan.c

@@ -21,6 +21,7 @@
 #include "driver_i.h"
 #include "mlme.h"
 #include "wps_supplicant.h"
+#include "ctrl_iface_dbus.h"
 
 
 static void wpa_supplicant_gen_assoc_event(struct wpa_supplicant *wpa_s)
@@ -328,6 +329,8 @@ static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
 	}
 #endif /* CONFIG_WPS */
 
+	wpa_supplicant_notify_scanning(wpa_s, 1);
+
 	if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME) {
 		ieee80211_sta_set_probe_req_ie(wpa_s, params.extra_ies,
 					       params.extra_ies_len);
@@ -344,6 +347,7 @@ static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
 
 	if (ret) {
 		wpa_printf(MSG_WARNING, "Failed to initiate AP scan.");
+		wpa_supplicant_notify_scanning(wpa_s, 0);
 		wpa_supplicant_req_scan(wpa_s, 10, 0);
 	} else
 		wpa_s->scan_runs++;
@@ -402,3 +406,14 @@ void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s)
 	wpa_msg(wpa_s, MSG_DEBUG, "Cancelling scan request");
 	eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
 }
+
+
+void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s,
+				    int scanning)
+{
+	if (wpa_s->scanning != scanning) {
+		wpa_s->scanning = scanning;
+		wpa_supplicant_dbus_notify_scanning(wpa_s);
+	}
+}
+

wpa_supplicant/wpa_supplicant.c

@@ -511,6 +511,9 @@ void wpa_supplicant_set_state(struct wpa_supplicant *wpa_s, wpa_states state)
 		   wpa_supplicant_state_txt(wpa_s->wpa_state),
 		   wpa_supplicant_state_txt(state));
 
+	if (state != WPA_SCANNING)
+		wpa_supplicant_notify_scanning(wpa_s, 0);
+
 	wpa_supplicant_dbus_notify_state_change(wpa_s, state,
 						wpa_s->wpa_state);
 

wpa_supplicant/wpa_supplicant_i.h

@@ -329,6 +329,7 @@ struct wpa_supplicant {
 	struct ctrl_iface_priv *ctrl_iface;
 
 	wpa_states wpa_state;
+	int scanning;
 	int new_connection;
 	int reassociated_connection;
 
@@ -431,6 +432,8 @@ int wpa_supplicant_scard_init(struct wpa_supplicant *wpa_s,
 /* scan.c */
 void wpa_supplicant_req_scan(struct wpa_supplicant *wpa_s, int sec, int usec);
 void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s);
+void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s,
+				    int scanning);
 
 /* events.c */
 void wpa_supplicant_mark_disassoc(struct wpa_supplicant *wpa_s);