dbus: Add D-Bus property for current MAC address

Since wpa_supplicant can change MAC address of the interface on its own
(with randomization enabled) it makes sense to introduce MACAddress as a
property of the interface and send notifications about its change.

This allows other applications to just use D-Bus instead of both
communicating over D-Bus with wpa_supplicant and listening to Netlink
notifications for MAC changes.

Signed-off-by: Andrzej Ostruszka <amo@semihalf.com>

doc/dbus.doxygen

@@ -1095,6 +1095,10 @@ fi.w1.wpa_supplicant1.CreateInterface.
 	<p>Masks to show which bits not to randomize with MAC address randomization. Possible keys are "scan", "sched_scan", and "pno". Values must be an array of 6 bytes.</p>
 	<p>When this property is set, the new dictionary replaces the old value, rather than merging them together. Leaving a key out of the dictionary will turn off MAC address randomization for that scan type.</p>
       </li>
+
+      <li>
+	<h3>MACAddress - ay - (read)</h3>
+	<p>MAC address of the interface</p>
     </ul>
 
 \subsection dbus_interface_signals Signals

wpa_supplicant/dbus/dbus_new.c

@@ -2344,6 +2344,9 @@ void wpas_dbus_signal_prop_changed(struct wpa_supplicant *wpa_s,
 	case WPAS_DBUS_PROP_BSS_TM_STATUS:
 		prop = "BSSTMStatus";
 		break;
+	case WPAS_DBUS_PROP_MAC_ADDRESS:
+		prop = "MACAddress";
+		break;
 	default:
 		wpa_printf(MSG_ERROR, "dbus: %s: Unknown Property value %d",
 			   __func__, property);
@@ -3939,6 +3942,11 @@ static const struct wpa_dbus_property_desc wpas_dbus_interface_properties[] = {
 	  wpas_dbus_setter_mac_address_randomization_mask,
 	  NULL
 	},
+	{ "MACAddress", WPAS_DBUS_NEW_IFACE_INTERFACE, "ay",
+	  wpas_dbus_getter_mac_address,
+	  NULL,
+	  NULL,
+	},
 	{ NULL, NULL, NULL, NULL, NULL, NULL }
 };
 

wpa_supplicant/dbus/dbus_new.h

@@ -38,6 +38,7 @@ enum wpas_dbus_prop {
 	WPAS_DBUS_PROP_ROAM_COMPLETE,
 	WPAS_DBUS_PROP_SESSION_LENGTH,
 	WPAS_DBUS_PROP_BSS_TM_STATUS,
+	WPAS_DBUS_PROP_MAC_ADDRESS,
 };
 
 enum wpas_dbus_bss_prop {

wpa_supplicant/dbus/dbus_new_handlers.c

@@ -4753,6 +4753,27 @@ dbus_bool_t wpas_dbus_getter_mac_address_randomization_mask(
 }
 
 
+/**
+ * wpas_dbus_getter_mac_address - Get MAC address of an interface
+ * @iter: Pointer to incoming dbus message iter
+ * @error: Location to store error on failure
+ * @user_data: Function specific data
+ * Returns: a list of stations
+ *
+ * Getter for "MACAddress" property.
+ */
+dbus_bool_t wpas_dbus_getter_mac_address(
+	const struct wpa_dbus_property_desc *property_desc,
+	DBusMessageIter *iter, DBusError *error, void *user_data)
+{
+	struct wpa_supplicant *wpa_s = user_data;
+
+	return wpas_dbus_simple_array_property_getter(iter, DBUS_TYPE_BYTE,
+						      wpa_s->own_addr, ETH_ALEN,
+						      error);
+}
+
+
 /**
  * wpas_dbus_getter_sta_address - Return the address of a connected station
  * @iter: Pointer to incoming dbus message iter

wpa_supplicant/dbus/dbus_new_handlers.h

@@ -196,6 +196,7 @@ DECLARE_ACCESSOR(wpas_dbus_getter_blobs);
 DECLARE_ACCESSOR(wpas_dbus_getter_stas);
 DECLARE_ACCESSOR(wpas_dbus_getter_mac_address_randomization_mask);
 DECLARE_ACCESSOR(wpas_dbus_setter_mac_address_randomization_mask);
+DECLARE_ACCESSOR(wpas_dbus_getter_mac_address);
 DECLARE_ACCESSOR(wpas_dbus_getter_sta_address);
 DECLARE_ACCESSOR(wpas_dbus_getter_sta_aid);
 DECLARE_ACCESSOR(wpas_dbus_getter_sta_caps);

wpa_supplicant/notify.c

@@ -213,6 +213,15 @@ void wpas_notify_bssid_changed(struct wpa_supplicant *wpa_s)
 }
 
 
+void wpas_notify_mac_address_changed(struct wpa_supplicant *wpa_s)
+{
+	if (wpa_s->p2p_mgmt)
+		return;
+
+	wpas_dbus_signal_prop_changed(wpa_s, WPAS_DBUS_PROP_MAC_ADDRESS);
+}
+
+
 void wpas_notify_auth_changed(struct wpa_supplicant *wpa_s)
 {
 	if (wpa_s->p2p_mgmt)

wpa_supplicant/notify.h

@@ -35,6 +35,7 @@ void wpas_notify_bss_tm_status(struct wpa_supplicant *wpa_s);
 void wpas_notify_network_changed(struct wpa_supplicant *wpa_s);
 void wpas_notify_ap_scan_changed(struct wpa_supplicant *wpa_s);
 void wpas_notify_bssid_changed(struct wpa_supplicant *wpa_s);
+void wpas_notify_mac_address_changed(struct wpa_supplicant *wpa_s);
 void wpas_notify_auth_changed(struct wpa_supplicant *wpa_s);
 void wpas_notify_network_enabled_changed(struct wpa_supplicant *wpa_s,
 					 struct wpa_ssid *ssid);

wpa_supplicant/wpa_supplicant.c

@@ -5360,6 +5360,10 @@ static int wpas_eapol_needs_l2_packet(struct wpa_supplicant *wpa_s)
 
 int wpa_supplicant_update_mac_addr(struct wpa_supplicant *wpa_s)
 {
+	u8 prev_mac_addr[ETH_ALEN];
+
+	os_memcpy(prev_mac_addr, wpa_s->own_addr, ETH_ALEN);
+
 	if ((!wpa_s->p2p_mgmt ||
 	     !(wpa_s->drv_flags & WPA_DRIVER_FLAGS_DEDICATED_P2P_DEVICE)) &&
 	    !(wpa_s->drv_flags & WPA_DRIVER_FLAGS_P2P_DEDICATED_INTERFACE)) {
@@ -5397,6 +5401,9 @@ int wpa_supplicant_update_mac_addr(struct wpa_supplicant *wpa_s)
 		fst_update_mac_addr(wpa_s->fst, wpa_s->own_addr);
 #endif /* CONFIG_FST */
 
+	if (os_memcmp(prev_mac_addr, wpa_s->own_addr, ETH_ALEN) != 0)
+		wpas_notify_mac_address_changed(wpa_s);
+
 	return 0;
 }