P2P: Do not add ctrl interface for P2P_DEVICE (p2p-dev-*)

Adding a new wpa_supplicant control interface for the dedicated
P2P_DEVICE would be quite confusing for programs that manage P2P
operations. Remove this control interface and require the global control
interface to be used since it will provide consistent interface for both
the new dedicated P2P_DEVICE (non-netdev) and old style P2P management
through a netdev.

Signed-hostap: Jouni Malinen <j@w1.fi>

wpa_supplicant/p2p_supplicant.c

@@ -1092,7 +1092,13 @@ wpas_p2p_init_group_interface(struct wpa_supplicant *wpa_s, int go)
 	os_memset(&iface, 0, sizeof(iface));
 	iface.ifname = wpa_s->pending_interface_name;
 	iface.driver = wpa_s->driver->name;
-	iface.ctrl_interface = wpa_s->conf->ctrl_interface;
+	if (wpa_s->conf->ctrl_interface == NULL &&
+	    wpa_s->parent != wpa_s &&
+	    wpa_s->p2p_mgmt &&
+	    (wpa_s->drv_flags & WPA_DRIVER_FLAGS_DEDICATED_P2P_DEVICE))
+		iface.ctrl_interface = wpa_s->parent->conf->ctrl_interface;
+	else
+		iface.ctrl_interface = wpa_s->conf->ctrl_interface;
 	iface.driver_param = wpa_s->conf->driver_param;
 	group_wpa_s = wpa_supplicant_add_iface(wpa_s->global, &iface);
 	if (group_wpa_s == NULL) {
@@ -3015,7 +3021,6 @@ int wpas_p2p_add_p2pdev_interface(struct wpa_supplicant *wpa_s)
 	iface.p2p_mgmt = 1;
 	iface.ifname = wpa_s->pending_interface_name;
 	iface.driver = wpa_s->driver->name;
-	iface.ctrl_interface = wpa_s->conf->ctrl_interface;
 	iface.driver_param = wpa_s->conf->driver_param;
 	iface.confname = wpa_s->confname;
 	p2pdev_wpa_s = wpa_supplicant_add_iface(wpa_s->global, &iface);
@@ -3023,6 +3028,7 @@ int wpas_p2p_add_p2pdev_interface(struct wpa_supplicant *wpa_s)
 		wpa_printf(MSG_DEBUG, "P2P: Failed to add P2P Device interface");
 		return -1;
 	}
+	p2pdev_wpa_s->parent = wpa_s;
 
 	wpa_s->pending_interface_name[0] = '\0';
 	return 0;

wpa_supplicant/wpa_supplicant.c

@@ -2838,6 +2838,11 @@ static int wpa_supplicant_init_iface(struct wpa_supplicant *wpa_s,
 			wpa_s->conf->driver_param =
 				os_strdup(iface->driver_param);
 		}
+
+		if (iface->p2p_mgmt && !iface->ctrl_interface) {
+			os_free(wpa_s->conf->ctrl_interface);
+			wpa_s->conf->ctrl_interface = NULL;
+		}
 	} else
 		wpa_s->conf = wpa_config_alloc_empty(iface->ctrl_interface,
 						     iface->driver_param);