Line data Source code
1 : /*
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>
7 : *
8 : * See wps_upnp.c for more details on licensing and code history.
9 : */
10 :
11 : #include "includes.h"
12 : #include <assert.h>
13 :
14 : #include "common.h"
15 : #include "eloop.h"
16 : #include "uuid.h"
17 : #include "http_client.h"
18 : #include "wps_defs.h"
19 : #include "wps_upnp.h"
20 : #include "wps_upnp_i.h"
21 :
22 : /*
23 : * Event message generation (to subscribers)
24 : *
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.
28 : *
29 : * Sending a message requires using a HTTP over TCP NOTIFY
30 : * (like a PUT) which requires a number of states..
31 : */
32 :
33 : #define MAX_EVENTS_QUEUED 20 /* How far behind queued events */
34 : #define MAX_FAILURES 10 /* Drop subscription after this many failures */
35 :
36 : /* How long to wait before sending event */
37 : #define EVENT_DELAY_SECONDS 0
38 : #define EVENT_DELAY_MSEC 0
39 :
40 : /*
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).
45 : *
46 : * TODO: As an optimization we could share data between subscribers.
47 : */
48 : struct wps_event_ {
49 : struct dl_list list;
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;
56 : };
57 :
58 :
59 : /* event_clean -- clean sockets etc. of event
60 : * Leaves data, retry count etc. alone.
61 : */
62 811 : static void event_clean(struct wps_event_ *e)
63 : {
64 811 : if (e->s->current_event == e)
65 764 : e->s->current_event = NULL;
66 811 : http_client_free(e->http_event);
67 811 : e->http_event = NULL;
68 811 : }
69 :
70 :
71 : /* event_delete -- delete single unqueued event
72 : * (be sure to dequeue first if need be)
73 : */
74 703 : static void event_delete(struct wps_event_ *e)
75 : {
76 703 : wpa_printf(MSG_DEBUG, "WPS UPnP: Delete event %p", e);
77 703 : event_clean(e);
78 703 : wpabuf_free(e->data);
79 703 : os_free(e);
80 703 : }
81 :
82 :
83 : /* event_dequeue -- get next event from the queue
84 : * Returns NULL if empty.
85 : */
86 819 : static struct wps_event_ *event_dequeue(struct subscription *s)
87 : {
88 : struct wps_event_ *e;
89 819 : e = dl_list_first(&s->event_queue, struct wps_event_, list);
90 819 : if (e) {
91 775 : wpa_printf(MSG_DEBUG, "WPS UPnP: Dequeue event %p for "
92 : "subscription %p", e, s);
93 775 : dl_list_del(&e->list);
94 : }
95 819 : return e;
96 : }
97 :
98 :
99 : /* event_delete_all -- delete entire event queue and current event */
100 44 : void event_delete_all(struct subscription *s)
101 : {
102 : struct wps_event_ *e;
103 98 : while ((e = event_dequeue(s)) != NULL)
104 10 : event_delete(e);
105 44 : if (s->current_event) {
106 2 : event_delete(s->current_event);
107 : /* will set: s->current_event = NULL; */
108 : }
109 44 : }
110 :
111 :
112 : /**
113 : * event_retry - Called when we had a failure delivering event msg
114 : * @e: Event
115 : * @do_next_address: skip address e.g. on connect fail
116 : */
117 108 : static void event_retry(struct wps_event_ *e, int do_next_address)
118 : {
119 108 : struct subscription *s = e->s;
120 108 : struct upnp_wps_device_sm *sm = s->sm;
121 :
122 108 : wpa_printf(MSG_DEBUG, "WPS UPnP: Retry event %p for subscription %p",
123 : e, s);
124 108 : event_clean(e);
125 : /* will set: s->current_event = NULL; */
126 :
127 108 : if (do_next_address) {
128 99 : e->retry++;
129 99 : wpa_printf(MSG_DEBUG, "WPS UPnP: Try address %d", e->retry);
130 : }
131 108 : if (e->retry >= dl_list_len(&s->addr_list)) {
132 36 : wpa_printf(MSG_DEBUG, "WPS UPnP: Giving up on sending event "
133 36 : "for %s", e->addr->domain_and_port);
134 36 : event_delete(e);
135 36 : s->last_event_failed = 1;
136 36 : if (!dl_list_empty(&s->event_queue))
137 14 : event_send_all_later(s->sm);
138 144 : return;
139 : }
140 72 : dl_list_add(&s->event_queue, &e->list);
141 72 : event_send_all_later(sm);
142 : }
143 :
144 :
145 764 : static struct wpabuf * event_build_message(struct wps_event_ *e)
146 : {
147 : struct wpabuf *buf;
148 : char *b;
149 :
150 764 : buf = wpabuf_alloc(1000 + wpabuf_len(e->data));
151 764 : if (buf == NULL)
152 1 : return NULL;
153 763 : wpabuf_printf(buf, "NOTIFY %s HTTP/1.1\r\n", e->addr->path);
154 763 : wpabuf_put_str(buf, "SERVER: Unspecified, UPnP/1.0, Unspecified\r\n");
155 763 : wpabuf_printf(buf, "HOST: %s\r\n", e->addr->domain_and_port);
156 763 : wpabuf_put_str(buf, "CONTENT-TYPE: text/xml; charset=\"utf-8\"\r\n"
157 : "NT: upnp:event\r\n"
158 : "NTS: upnp:propchange\r\n");
159 763 : wpabuf_put_str(buf, "SID: uuid:");
160 763 : b = wpabuf_put(buf, 0);
161 763 : uuid_bin2str(e->s->uuid, b, 80);
162 763 : wpabuf_put(buf, os_strlen(b));
163 763 : wpabuf_put_str(buf, "\r\n");
164 763 : wpabuf_printf(buf, "SEQ: %u\r\n", e->subscriber_sequence);
165 763 : wpabuf_printf(buf, "CONTENT-LENGTH: %d\r\n",
166 763 : (int) wpabuf_len(e->data));
167 763 : wpabuf_put_str(buf, "\r\n"); /* terminating empty line */
168 763 : wpabuf_put_buf(buf, e->data);
169 763 : return buf;
170 : }
171 :
172 :
173 108 : static void event_addr_failure(struct wps_event_ *e)
174 : {
175 108 : struct subscription *s = e->s;
176 :
177 108 : e->addr->num_failures++;
178 216 : wpa_printf(MSG_DEBUG, "WPS UPnP: Failed to send event %p to %s "
179 : "(num_failures=%u)",
180 216 : e, e->addr->domain_and_port, e->addr->num_failures);
181 :
182 108 : if (e->addr->num_failures < MAX_FAILURES) {
183 : /* Try other addresses, if available */
184 99 : event_retry(e, 1);
185 99 : return;
186 : }
187 :
188 : /*
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...).
191 : */
192 9 : wpa_printf(MSG_DEBUG, "WPS UPnP: Deleting subscription %p "
193 9 : "address %s due to errors", s, e->addr->domain_and_port);
194 9 : dl_list_del(&e->addr->list);
195 9 : subscr_addr_delete(e->addr);
196 9 : e->addr = NULL;
197 :
198 9 : if (dl_list_empty(&s->addr_list)) {
199 : /* if we've given up on all addresses */
200 2 : wpa_printf(MSG_DEBUG, "WPS UPnP: Removing subscription %p "
201 : "with no addresses", s);
202 2 : dl_list_del(&s->list);
203 2 : subscription_destroy(s);
204 2 : return;
205 : }
206 :
207 : /* Try other addresses, if available */
208 7 : event_retry(e, 0);
209 : }
210 :
211 :
212 762 : static void event_http_cb(void *ctx, struct http_client *c,
213 : enum http_client_event event)
214 : {
215 762 : struct wps_event_ *e = ctx;
216 762 : struct subscription *s = e->s;
217 :
218 762 : wpa_printf(MSG_DEBUG, "WPS UPnP: HTTP client callback: e=%p c=%p "
219 : "event=%d", e, c, event);
220 762 : switch (event) {
221 : case HTTP_CLIENT_OK:
222 654 : wpa_printf(MSG_DEBUG,
223 : "WPS UPnP: Got event %p reply OK from %s",
224 654 : e, e->addr->domain_and_port);
225 654 : e->addr->num_failures = 0;
226 654 : s->last_event_failed = 0;
227 654 : event_delete(e);
228 :
229 : /* Schedule sending more if there is more to send */
230 654 : if (!dl_list_empty(&s->event_queue))
231 11 : event_send_all_later(s->sm);
232 654 : break;
233 : case HTTP_CLIENT_FAILED:
234 108 : wpa_printf(MSG_DEBUG, "WPS UPnP: Event send failure");
235 108 : event_addr_failure(e);
236 108 : break;
237 : case HTTP_CLIENT_INVALID_REPLY:
238 0 : wpa_printf(MSG_DEBUG, "WPS UPnP: Invalid reply");
239 0 : event_addr_failure(e);
240 0 : break;
241 : case HTTP_CLIENT_TIMEOUT:
242 0 : wpa_printf(MSG_DEBUG, "WPS UPnP: Event send timeout");
243 0 : event_addr_failure(e);
244 0 : break;
245 : }
246 762 : }
247 :
248 :
249 : /* event_send_start -- prepare to send a event message to subscriber
250 : *
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.
263 : *
264 : * Returns nonzero on error;
265 : *
266 : * Prerequisite: No current event send (s->current_event == NULL)
267 : * and non-empty queue.
268 : */
269 764 : static int event_send_start(struct subscription *s)
270 : {
271 : struct wps_event_ *e;
272 : unsigned int itry;
273 : struct wpabuf *buf;
274 :
275 : /*
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.
278 : */
279 1528 : if (dl_list_empty(&s->addr_list) ||
280 1528 : s->current_event ||
281 764 : dl_list_empty(&s->event_queue))
282 0 : return -1;
283 :
284 764 : s->current_event = e = event_dequeue(s);
285 :
286 : /* Use address according to number of retries */
287 764 : itry = 0;
288 1016 : dl_list_for_each(e->addr, &s->addr_list, struct subscr_addr, list)
289 1016 : if (itry++ == e->retry)
290 764 : break;
291 764 : if (itry < e->retry)
292 0 : return -1;
293 :
294 764 : buf = event_build_message(e);
295 764 : if (buf == NULL) {
296 1 : event_retry(e, 0);
297 1 : return -1;
298 : }
299 :
300 763 : e->http_event = http_client_addr(&e->addr->saddr, buf, 0,
301 : event_http_cb, e);
302 763 : if (e->http_event == NULL) {
303 1 : wpabuf_free(buf);
304 1 : event_retry(e, 0);
305 1 : return -1;
306 : }
307 :
308 762 : return 0;
309 : }
310 :
311 :
312 : /* event_send_all_later_handler -- actually send events as needed */
313 787 : static void event_send_all_later_handler(void *eloop_data, void *user_ctx)
314 : {
315 787 : struct upnp_wps_device_sm *sm = user_ctx;
316 : struct subscription *s, *tmp;
317 787 : int nerrors = 0;
318 :
319 787 : sm->event_send_all_queued = 0;
320 1604 : dl_list_for_each_safe(s, tmp, &sm->subscriptions, struct subscription,
321 : list) {
322 1601 : if (s->current_event == NULL /* not busy */ &&
323 784 : !dl_list_empty(&s->event_queue) /* more to do */) {
324 764 : if (event_send_start(s))
325 2 : nerrors++;
326 : }
327 : }
328 :
329 787 : if (nerrors) {
330 : /* Try again later */
331 2 : event_send_all_later(sm);
332 : }
333 787 : }
334 :
335 :
336 : /* event_send_all_later -- schedule sending events to all subscribers
337 : * that need it.
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.
342 : */
343 839 : void event_send_all_later(struct upnp_wps_device_sm *sm)
344 : {
345 : /*
346 : * The exact time in the future isn't too important. Waiting a bit
347 : * might let us do several together.
348 : */
349 839 : if (sm->event_send_all_queued)
350 891 : return;
351 787 : sm->event_send_all_queued = 1;
352 787 : eloop_register_timeout(EVENT_DELAY_SECONDS, EVENT_DELAY_MSEC,
353 : event_send_all_later_handler, NULL, sm);
354 : }
355 :
356 :
357 : /* event_send_stop_all -- cleanup */
358 37 : void event_send_stop_all(struct upnp_wps_device_sm *sm)
359 : {
360 37 : if (sm->event_send_all_queued)
361 0 : eloop_cancel_timeout(event_send_all_later_handler, NULL, sm);
362 37 : sm->event_send_all_queued = 0;
363 37 : }
364 :
365 :
366 : /**
367 : * event_add - Add a new event to a queue
368 : * @s: Subscription
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
372 : */
373 714 : int event_add(struct subscription *s, const struct wpabuf *data, int probereq)
374 : {
375 : struct wps_event_ *e;
376 : unsigned int len;
377 :
378 714 : len = dl_list_len(&s->event_queue);
379 714 : if (len >= MAX_EVENTS_QUEUED) {
380 8 : wpa_printf(MSG_DEBUG, "WPS UPnP: Too many events queued for "
381 : "subscriber %p", s);
382 8 : if (probereq)
383 7 : return 1;
384 :
385 : /* Drop oldest entry to allow EAP event to be stored. */
386 1 : e = event_dequeue(s);
387 1 : if (!e)
388 0 : return 1;
389 1 : event_delete(e);
390 : }
391 :
392 707 : if (s->last_event_failed && probereq && len > 0) {
393 : /*
394 : * Avoid queuing frames for subscribers that may have left
395 : * without unsubscribing.
396 : */
397 1 : wpa_printf(MSG_DEBUG, "WPS UPnP: Do not queue more Probe "
398 : "Request frames for subscription %p since last "
399 : "delivery failed", s);
400 1 : return -1;
401 : }
402 :
403 706 : e = os_zalloc(sizeof(*e));
404 706 : if (e == NULL)
405 2 : return -1;
406 704 : dl_list_init(&e->list);
407 704 : e->s = s;
408 704 : e->data = wpabuf_dup(data);
409 704 : if (e->data == NULL) {
410 1 : os_free(e);
411 1 : return -1;
412 : }
413 703 : e->subscriber_sequence = s->next_subscriber_sequence++;
414 703 : if (s->next_subscriber_sequence == 0)
415 0 : s->next_subscriber_sequence++;
416 703 : wpa_printf(MSG_DEBUG, "WPS UPnP: Queue event %p for subscriber %p "
417 : "(queue len %u)", e, s, len + 1);
418 703 : dl_list_add_tail(&s->event_queue, &e->list);
419 703 : event_send_all_later(s->sm);
420 703 : return 0;
421 : }
|
