2 * UPnP WPS Device - Event processing
3 * Copyright (c) 2000-2003 Intel Corporation
4 * Copyright (c) 2006-2007 Sony Corporation
5 * Copyright (c) 2008-2009 Atheros Communications
6 * Copyright (c) 2009-2010, Jouni Malinen <j@w1.fi>
8 * See wps_upnp.c for more details on licensing and code history.
17 #include "http_client.h"
20 #include "wps_upnp_i.h"
23 * Event message generation (to subscribers)
25 * We make a separate copy for each message for each subscriber. This memory
26 * wasted could be limited (adding code complexity) by sharing copies, keeping
27 * a usage count and freeing when zero.
29 * Sending a message requires using a HTTP over TCP NOTIFY
30 * (like a PUT) which requires a number of states..
33 #define MAX_EVENTS_QUEUED 20 /* How far behind queued events */
34 #define MAX_FAILURES 10 /* Drop subscription after this many failures */
36 /* How long to wait before sending event */
37 #define EVENT_DELAY_SECONDS 0
38 #define EVENT_DELAY_MSEC 0
41 * Event information that we send to each subscriber is remembered in this
42 * struct. The event cannot be sent by simple UDP; it has to be sent by a HTTP
43 * over TCP transaction which requires various states.. It may also need to be
44 * retried at a different address (if more than one is available).
46 * TODO: As an optimization we could share data between subscribers.
50 struct subscription *s; /* parent */
51 unsigned subscriber_sequence; /* which event for this subscription*/
52 unsigned int retry; /* which retry */
53 struct subscr_addr *addr; /* address to connect to */
54 struct wpabuf *data; /* event data to send */
55 struct http_client *http_event;
59 /* event_clean -- clean sockets etc. of event
60 * Leaves data, retry count etc. alone.
62 static void event_clean(struct wps_event_ *e)
64 if (e->s->current_event == e)
65 e->s->current_event = NULL;
66 http_client_free(e->http_event);
71 /* event_delete -- delete single unqueued event
72 * (be sure to dequeue first if need be)
74 static void event_delete(struct wps_event_ *e)
76 wpa_printf(MSG_DEBUG, "WPS UPnP: Delete event %p", e);
83 /* event_dequeue -- get next event from the queue
84 * Returns NULL if empty.
86 static struct wps_event_ *event_dequeue(struct subscription *s)
89 e = dl_list_first(&s->event_queue, struct wps_event_, list);
91 wpa_printf(MSG_DEBUG, "WPS UPnP: Dequeue event %p for "
92 "subscription %p", e, s);
93 dl_list_del(&e->list);
99 /* event_delete_all -- delete entire event queue and current event */
100 void event_delete_all(struct subscription *s)
102 struct wps_event_ *e;
103 while ((e = event_dequeue(s)) != NULL)
105 if (s->current_event) {
106 event_delete(s->current_event);
107 /* will set: s->current_event = NULL; */
113 * event_retry - Called when we had a failure delivering event msg
115 * @do_next_address: skip address e.g. on connect fail
117 static void event_retry(struct wps_event_ *e, int do_next_address)
119 struct subscription *s = e->s;
120 struct upnp_wps_device_sm *sm = s->sm;
122 wpa_printf(MSG_DEBUG, "WPS UPnP: Retry event %p for subscription %p",
125 /* will set: s->current_event = NULL; */
127 if (do_next_address) {
129 wpa_printf(MSG_DEBUG, "WPS UPnP: Try address %d", e->retry);
131 if (e->retry >= dl_list_len(&s->addr_list)) {
132 wpa_printf(MSG_DEBUG, "WPS UPnP: Giving up on sending event "
133 "for %s", e->addr->domain_and_port);
135 s->last_event_failed = 1;
136 if (!dl_list_empty(&s->event_queue))
137 event_send_all_later(s->sm);
140 dl_list_add(&s->event_queue, &e->list);
141 event_send_all_later(sm);
145 static struct wpabuf * event_build_message(struct wps_event_ *e)
150 buf = wpabuf_alloc(1000 + wpabuf_len(e->data));
153 wpabuf_printf(buf, "NOTIFY %s HTTP/1.1\r\n", e->addr->path);
154 wpabuf_put_str(buf, "SERVER: Unspecified, UPnP/1.0, Unspecified\r\n");
155 wpabuf_printf(buf, "HOST: %s\r\n", e->addr->domain_and_port);
156 wpabuf_put_str(buf, "CONTENT-TYPE: text/xml; charset=\"utf-8\"\r\n"
158 "NTS: upnp:propchange\r\n");
159 wpabuf_put_str(buf, "SID: uuid:");
160 b = wpabuf_put(buf, 0);
161 uuid_bin2str(e->s->uuid, b, 80);
162 wpabuf_put(buf, os_strlen(b));
163 wpabuf_put_str(buf, "\r\n");
164 wpabuf_printf(buf, "SEQ: %u\r\n", e->subscriber_sequence);
165 wpabuf_printf(buf, "CONTENT-LENGTH: %d\r\n",
166 (int) wpabuf_len(e->data));
167 wpabuf_put_str(buf, "\r\n"); /* terminating empty line */
168 wpabuf_put_buf(buf, e->data);
173 static void event_addr_failure(struct wps_event_ *e)
175 struct subscription *s = e->s;
177 e->addr->num_failures++;
178 wpa_printf(MSG_DEBUG, "WPS UPnP: Failed to send event %p to %s "
180 e, e->addr->domain_and_port, e->addr->num_failures);
182 if (e->addr->num_failures < MAX_FAILURES) {
183 /* Try other addresses, if available */
189 * If other side doesn't like what we say, forget about them.
190 * (There is no way to tell other side that we are dropping them...).
192 wpa_printf(MSG_DEBUG, "WPS UPnP: Deleting subscription %p "
193 "address %s due to errors", s, e->addr->domain_and_port);
194 dl_list_del(&e->addr->list);
195 subscr_addr_delete(e->addr);
198 if (dl_list_empty(&s->addr_list)) {
199 /* if we've given up on all addresses */
200 wpa_printf(MSG_DEBUG, "WPS UPnP: Removing subscription %p "
201 "with no addresses", s);
202 dl_list_del(&s->list);
203 subscription_destroy(s);
207 /* Try other addresses, if available */
212 static void event_http_cb(void *ctx, struct http_client *c,
213 enum http_client_event event)
215 struct wps_event_ *e = ctx;
216 struct subscription *s = e->s;
218 wpa_printf(MSG_DEBUG, "WPS UPnP: HTTP client callback: e=%p c=%p "
219 "event=%d", e, c, event);
222 wpa_printf(MSG_DEBUG,
223 "WPS UPnP: Got event %p reply OK from %s",
224 e, e->addr->domain_and_port);
225 e->addr->num_failures = 0;
226 s->last_event_failed = 0;
229 /* Schedule sending more if there is more to send */
230 if (!dl_list_empty(&s->event_queue))
231 event_send_all_later(s->sm);
233 case HTTP_CLIENT_FAILED:
234 wpa_printf(MSG_DEBUG, "WPS UPnP: Event send failure");
235 event_addr_failure(e);
237 case HTTP_CLIENT_INVALID_REPLY:
238 wpa_printf(MSG_DEBUG, "WPS UPnP: Invalid reply");
239 event_addr_failure(e);
241 case HTTP_CLIENT_TIMEOUT:
242 wpa_printf(MSG_DEBUG, "WPS UPnP: Event send timeout");
243 event_addr_failure(e);
249 /* event_send_start -- prepare to send a event message to subscriber
251 * This gets complicated because:
252 * -- The message is sent via TCP and we have to keep the stream open
253 * for 30 seconds to get a response... then close it.
254 * -- But we might have other event happen in the meantime...
255 * we have to queue them, if we lose them then the subscriber will
256 * be forced to unsubscribe and subscribe again.
257 * -- If multiple URLs are provided then we are supposed to try successive
258 * ones after 30 second timeout.
259 * -- The URLs might use domain names instead of dotted decimal addresses,
260 * and resolution of those may cause unwanted sleeping.
261 * -- Doing the initial TCP connect can take a while, so we have to come
262 * back after connection and then send the data.
264 * Returns nonzero on error;
266 * Prerequisite: No current event send (s->current_event == NULL)
267 * and non-empty queue.
269 static int event_send_start(struct subscription *s)
271 struct wps_event_ *e;
276 * Assume we are called ONLY with no current event and ONLY with
277 * nonempty event queue and ONLY with at least one address to send to.
279 if (dl_list_empty(&s->addr_list) ||
281 dl_list_empty(&s->event_queue))
284 s->current_event = e = event_dequeue(s);
286 /* Use address according to number of retries */
288 dl_list_for_each(e->addr, &s->addr_list, struct subscr_addr, list)
289 if (itry++ == e->retry)
294 buf = event_build_message(e);
300 e->http_event = http_client_addr(&e->addr->saddr, buf, 0,
302 if (e->http_event == NULL) {
312 /* event_send_all_later_handler -- actually send events as needed */
313 static void event_send_all_later_handler(void *eloop_data, void *user_ctx)
315 struct upnp_wps_device_sm *sm = user_ctx;
316 struct subscription *s, *tmp;
319 sm->event_send_all_queued = 0;
320 dl_list_for_each_safe(s, tmp, &sm->subscriptions, struct subscription,
322 if (s->current_event == NULL /* not busy */ &&
323 !dl_list_empty(&s->event_queue) /* more to do */) {
324 if (event_send_start(s))
330 /* Try again later */
331 event_send_all_later(sm);
336 /* event_send_all_later -- schedule sending events to all subscribers
338 * This avoids two problems:
339 * -- After getting a subscription, we should not send the first event
340 * until after our reply is fully queued to be sent back,
341 * -- Possible stack depth or infinite recursion issues.
343 void event_send_all_later(struct upnp_wps_device_sm *sm)
346 * The exact time in the future isn't too important. Waiting a bit
347 * might let us do several together.
349 if (sm->event_send_all_queued)
351 sm->event_send_all_queued = 1;
352 eloop_register_timeout(EVENT_DELAY_SECONDS, EVENT_DELAY_MSEC,
353 event_send_all_later_handler, NULL, sm);
357 /* event_send_stop_all -- cleanup */
358 void event_send_stop_all(struct upnp_wps_device_sm *sm)
360 if (sm->event_send_all_queued)
361 eloop_cancel_timeout(event_send_all_later_handler, NULL, sm);
362 sm->event_send_all_queued = 0;
367 * event_add - Add a new event to a queue
369 * @data: Event data (is copied; caller retains ownership)
370 * @probereq: Whether this is a Probe Request event
371 * Returns: 0 on success, -1 on error, 1 on max event queue limit reached
373 int event_add(struct subscription *s, const struct wpabuf *data, int probereq)
375 struct wps_event_ *e;
378 len = dl_list_len(&s->event_queue);
379 if (len >= MAX_EVENTS_QUEUED) {
380 wpa_printf(MSG_DEBUG, "WPS UPnP: Too many events queued for "
385 /* Drop oldest entry to allow EAP event to be stored. */
386 e = event_dequeue(s);
392 if (s->last_event_failed && probereq && len > 0) {
394 * Avoid queuing frames for subscribers that may have left
395 * without unsubscribing.
397 wpa_printf(MSG_DEBUG, "WPS UPnP: Do not queue more Probe "
398 "Request frames for subscription %p since last "
399 "delivery failed", s);
403 e = os_zalloc(sizeof(*e));
406 dl_list_init(&e->list);
408 e->data = wpabuf_dup(data);
409 if (e->data == NULL) {
413 e->subscriber_sequence = s->next_subscriber_sequence++;
414 if (s->next_subscriber_sequence == 0)
415 s->next_subscriber_sequence++;
416 wpa_printf(MSG_DEBUG, "WPS UPnP: Queue event %p for subscriber %p "
417 "(queue len %u)", e, s, len + 1);
418 dl_list_add_tail(&s->event_queue, &e->list);
419 event_send_all_later(s->sm);