WPS UPnP: Improved event notification failure processing

Instead of dropping the subscription on first failure, allow up to
10 failures before dropping. In addition, drop the callback URLs
one by one instead of full subscription if only one URL is failing.

src/wps/wps_upnp.c

@@ -270,7 +270,7 @@ static void uuid_make(u8 uuid[UUID_LEN])
 /* subscr_addr_delete -- delete single unlinked subscriber address
  * (be sure to unlink first if need be)
  */
-static void subscr_addr_delete(struct subscr_addr *a)
+void subscr_addr_delete(struct subscr_addr *a)
 {
 	/*
 	 * Note: do NOT free domain_and_port or path because they point to

src/wps/wps_upnp_event.c

@@ -31,6 +31,7 @@
  */
 
 #define MAX_EVENTS_QUEUED 20   /* How far behind queued events */
+#define MAX_FAILURES 10 /* Drop subscription after this many failures */
 
 /* How long to wait before sending event */
 #define EVENT_DELAY_SECONDS 0
@@ -166,6 +167,45 @@ static struct wpabuf * event_build_message(struct wps_event_ *e)
 }
 
 
+static void event_addr_failure(struct wps_event_ *e)
+{
+	struct subscription *s = e->s;
+
+	e->addr->num_failures++;
+	wpa_printf(MSG_DEBUG, "WPS UPnP: Failed to send event %p to %s "
+		   "(num_failures=%u)",
+		   e, e->addr->domain_and_port, e->addr->num_failures);
+
+	if (e->addr->num_failures < MAX_FAILURES) {
+		/* Try other addresses, if available */
+		event_retry(e, 1);
+		return;
+	}
+
+	/*
+	 * If other side doesn't like what we say, forget about them.
+	 * (There is no way to tell other side that we are dropping them...).
+	 */
+	wpa_printf(MSG_DEBUG, "WPS UPnP: Deleting subscription %p "
+		   "address %s due to errors", s, e->addr->domain_and_port);
+	dl_list_del(&e->addr->list);
+	subscr_addr_delete(e->addr);
+	e->addr = NULL;
+
+	if (dl_list_empty(&s->addr_list)) {
+		/* if we've given up on all addresses */
+		wpa_printf(MSG_DEBUG, "WPS UPnP: Removing subscription %p "
+			   "with no addresses", s);
+		dl_list_del(&s->list);
+		subscription_destroy(s);
+		return;
+	}
+
+	/* Try other addresses, if available */
+	event_retry(e, 0);
+}
+
+
 static void event_http_cb(void *ctx, struct http_client *c,
 			  enum http_client_event event)
 {
@@ -179,6 +219,7 @@ static void event_http_cb(void *ctx, struct http_client *c,
 		wpa_printf(MSG_DEBUG,
 			   "WPS UPnP: Got event %p reply OK from %s",
 			   e, e->addr->domain_and_port);
+		e->addr->num_failures = 0;
 		event_delete(e);
 
 		/* Schedule sending more if there is more to send */
@@ -186,24 +227,17 @@ static void event_http_cb(void *ctx, struct http_client *c,
 			event_send_all_later(s->sm);
 		break;
 	case HTTP_CLIENT_FAILED:
+		wpa_printf(MSG_DEBUG, "WPS UPnP: Event send failure");
+		event_addr_failure(e);
+		break;
 	case HTTP_CLIENT_INVALID_REPLY:
-		wpa_printf(MSG_DEBUG, "WPS UPnP: Failed to send event to %s",
-			   e->addr->domain_and_port);
-
-		/*
-		 * If other side doesn't like what we say, forget about them.
-		 * (There is no way to tell other side that we are dropping
-		 * them...).
-		 * Alternately, we could just do event_delete(e)
-		 */
-		wpa_printf(MSG_DEBUG, "WPS UPnP: Deleting subscription due to "
-			   "errors");
-		dl_list_del(&s->list);
-		subscription_destroy(s);
+		wpa_printf(MSG_DEBUG, "WPS UPnP: Invalid reply");
+		event_addr_failure(e);
 		break;
 	case HTTP_CLIENT_TIMEOUT:
 		wpa_printf(MSG_DEBUG, "WPS UPnP: Event send timeout");
-		event_retry(e, 1);
+		event_addr_failure(e);
+		break;
 	}
 }
 
@@ -283,18 +317,10 @@ static void event_send_all_later_handler(void *eloop_data, void *user_ctx)
 	sm->event_send_all_queued = 0;
 	dl_list_for_each_safe(s, tmp, &sm->subscriptions, struct subscription,
 			      list) {
-		if (dl_list_empty(&s->addr_list)) {
-			/* if we've given up on all addresses */
-			wpa_printf(MSG_DEBUG, "WPS UPnP: Removing "
-				   "subscription with no addresses");
-			dl_list_del(&s->list);
-			subscription_destroy(s);
-		} else {
-			if (s->current_event == NULL /* not busy */ &&
-			    !dl_list_empty(&s->event_queue) /* more to do */) {
-				if (event_send_start(s))
-					nerrors++;
-			}
+		if (s->current_event == NULL /* not busy */ &&
+		    !dl_list_empty(&s->event_queue) /* more to do */) {
+			if (event_send_start(s))
+				nerrors++;
 		}
 	}
 

src/wps/wps_upnp_i.h

@@ -67,6 +67,7 @@ struct subscr_addr {
 	char *domain_and_port; /* domain and port part of url */
 	char *path; /* "filepath" part of url (from "mem") */
 	struct sockaddr_in saddr; /* address for doing connect */
+	unsigned num_failures;
 };
 
 
@@ -145,6 +146,7 @@ struct subscription * subscription_renew(struct upnp_wps_device_sm *sm,
 void subscription_destroy(struct subscription *s);
 struct subscription * subscription_find(struct upnp_wps_device_sm *sm,
 					const u8 uuid[UUID_LEN]);
+void subscr_addr_delete(struct subscr_addr *a);
 int send_wpabuf(int fd, struct wpabuf *buf);
 int get_netif_info(const char *net_if, unsigned *ip_addr, char **ip_addr_text,
 		   u8 mac[ETH_ALEN]);