[thirdparty/hostap.git] / src / wps / wps_upnp_event.c

/*
 * UPnP WPS Device - Event processing
 * Copyright (c) 2000-2003 Intel Corporation
 * Copyright (c) 2006-2007 Sony Corporation
 * Copyright (c) 2008-2009 Atheros Communications
 * Copyright (c) 2009-2010, Jouni Malinen <j@w1.fi>
 *
 * See wps_upnp.c for more details on licensing and code history.
 */

#include "includes.h"
#include <assert.h>

#include "common.h"
#include "eloop.h"
#include "uuid.h"
#include "http_client.h"
#include "wps_defs.h"
#include "wps_upnp.h"
#include "wps_upnp_i.h"

/*
 * Event message generation (to subscribers)
 *
 * We make a separate copy for each message for each subscriber. This memory
 * wasted could be limited (adding code complexity) by sharing copies, keeping
 * a usage count and freeing when zero.
 *
 * Sending a message requires using a HTTP over TCP NOTIFY
 * (like a PUT) which requires a number of states..
 */

#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
#define EVENT_DELAY_MSEC 0

/*
 * Event information that we send to each subscriber is remembered in this
 * struct. The event cannot be sent by simple UDP; it has to be sent by a HTTP
 * over TCP transaction which requires various states.. It may also need to be
 * retried at a different address (if more than one is available).
 *
 * TODO: As an optimization we could share data between subscribers.
 */
struct wps_event_ {
	struct dl_list list;
	struct subscription *s;         /* parent */
	unsigned subscriber_sequence;   /* which event for this subscription*/
	unsigned int retry;             /* which retry */
	struct subscr_addr *addr;       /* address to connect to */
	struct wpabuf *data;            /* event data to send */
	struct http_client *http_event;
};


/* event_clean -- clean sockets etc. of event
 * Leaves data, retry count etc. alone.
 */
static void event_clean(struct wps_event_ *e)
{
	if (e->s->current_event == e)
		e->s->current_event = NULL;
	http_client_free(e->http_event);
	e->http_event = NULL;
}


/* event_delete -- delete single unqueued event
 * (be sure to dequeue first if need be)
 */
static void event_delete(struct wps_event_ *e)
{
	wpa_printf(MSG_DEBUG, "WPS UPnP: Delete event %p", e);
	event_clean(e);
	wpabuf_free(e->data);
	os_free(e);
}


/* event_dequeue -- get next event from the queue
 * Returns NULL if empty.
 */
static struct wps_event_ *event_dequeue(struct subscription *s)
{
	struct wps_event_ *e;
	e = dl_list_first(&s->event_queue, struct wps_event_, list);
	if (e) {
		wpa_printf(MSG_DEBUG, "WPS UPnP: Dequeue event %p for "
			   "subscription %p", e, s);
		dl_list_del(&e->list);
	}
	return e;
}


/* event_delete_all -- delete entire event queue and current event */
void event_delete_all(struct subscription *s)
{
	struct wps_event_ *e;
	while ((e = event_dequeue(s)) != NULL)
		event_delete(e);
	if (s->current_event) {
		event_delete(s->current_event);
		/* will set: s->current_event = NULL;  */
	}
}


/**
 * event_retry - Called when we had a failure delivering event msg
 * @e: Event
 * @do_next_address: skip address e.g. on connect fail
 */
static void event_retry(struct wps_event_ *e, int do_next_address)
{
	struct subscription *s = e->s;
	struct upnp_wps_device_sm *sm = s->sm;

	wpa_printf(MSG_DEBUG, "WPS UPnP: Retry event %p for subscription %p",
		   e, s);
	event_clean(e);
	/* will set: s->current_event = NULL; */

	if (do_next_address) {
		e->retry++;
		wpa_printf(MSG_DEBUG, "WPS UPnP: Try address %d", e->retry);
	}
	if (e->retry >= dl_list_len(&s->addr_list)) {
		wpa_printf(MSG_DEBUG, "WPS UPnP: Giving up on sending event "
			   "for %s", e->addr->domain_and_port);
		event_delete(e);
		s->last_event_failed = 1;
		if (!dl_list_empty(&s->event_queue))
			event_send_all_later(s->sm);
		return;
	}
	dl_list_add(&s->event_queue, &e->list);
	event_send_all_later(sm);
}


static struct wpabuf * event_build_message(struct wps_event_ *e)
{
	struct wpabuf *buf;
	char *b;

	buf = wpabuf_alloc(1000 + wpabuf_len(e->data));
	if (buf == NULL)
		return NULL;
	wpabuf_printf(buf, "NOTIFY %s HTTP/1.1\r\n", e->addr->path);
	wpabuf_put_str(buf, "SERVER: Unspecified, UPnP/1.0, Unspecified\r\n");
	wpabuf_printf(buf, "HOST: %s\r\n", e->addr->domain_and_port);
	wpabuf_put_str(buf, "CONTENT-TYPE: text/xml; charset=\"utf-8\"\r\n"
		       "NT: upnp:event\r\n"
		       "NTS: upnp:propchange\r\n");
	wpabuf_put_str(buf, "SID: uuid:");
	b = wpabuf_put(buf, 0);
	uuid_bin2str(e->s->uuid, b, 80);
	wpabuf_put(buf, os_strlen(b));
	wpabuf_put_str(buf, "\r\n");
	wpabuf_printf(buf, "SEQ: %u\r\n", e->subscriber_sequence);
	wpabuf_printf(buf, "CONTENT-LENGTH: %d\r\n",
		      (int) wpabuf_len(e->data));
	wpabuf_put_str(buf, "\r\n"); /* terminating empty line */
	wpabuf_put_buf(buf, e->data);
	return buf;
}


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)
{
	struct wps_event_ *e = ctx;
	struct subscription *s = e->s;

	wpa_printf(MSG_DEBUG, "WPS UPnP: HTTP client callback: e=%p c=%p "
		   "event=%d", e, c, event);
	switch (event) {
	case HTTP_CLIENT_OK:
		wpa_printf(MSG_DEBUG,
			   "WPS UPnP: Got event %p reply OK from %s",
			   e, e->addr->domain_and_port);
		e->addr->num_failures = 0;
		s->last_event_failed = 0;
		event_delete(e);

		/* Schedule sending more if there is more to send */
		if (!dl_list_empty(&s->event_queue))
			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: Invalid reply");
		event_addr_failure(e);
		break;
	case HTTP_CLIENT_TIMEOUT:
		wpa_printf(MSG_DEBUG, "WPS UPnP: Event send timeout");
		event_addr_failure(e);
		break;
	}
}


/* event_send_start -- prepare to send a event message to subscriber
 *
 * This gets complicated because:
 * -- The message is sent via TCP and we have to keep the stream open
 *      for 30 seconds to get a response... then close it.
 * -- But we might have other event happen in the meantime...
 *      we have to queue them, if we lose them then the subscriber will
 *      be forced to unsubscribe and subscribe again.
 * -- If multiple URLs are provided then we are supposed to try successive
 *      ones after 30 second timeout.
 * -- The URLs might use domain names instead of dotted decimal addresses,
 *      and resolution of those may cause unwanted sleeping.
 * -- Doing the initial TCP connect can take a while, so we have to come
 *      back after connection and then send the data.
 *
 * Returns nonzero on error;
 *
 * Prerequisite: No current event send (s->current_event == NULL)
 *      and non-empty queue.
 */
static int event_send_start(struct subscription *s)
{
	struct wps_event_ *e;
	unsigned int itry;
	struct wpabuf *buf;

	/*
	 * Assume we are called ONLY with no current event and ONLY with
	 * nonempty event queue and ONLY with at least one address to send to.
	 */
	if (dl_list_empty(&s->addr_list))
		return -1;
	if (s->current_event)
		return -1;
	if (dl_list_empty(&s->event_queue))
		return -1;

	s->current_event = e = event_dequeue(s);

	/* Use address according to number of retries */
	itry = 0;
	dl_list_for_each(e->addr, &s->addr_list, struct subscr_addr, list)
		if (itry++ == e->retry)
			break;
	if (itry < e->retry)
		return -1;

	buf = event_build_message(e);
	if (buf == NULL) {
		event_retry(e, 0);
		return -1;
	}

	e->http_event = http_client_addr(&e->addr->saddr, buf, 0,
					 event_http_cb, e);
	if (e->http_event == NULL) {
		wpabuf_free(buf);
		event_retry(e, 0);
		return -1;
	}

	return 0;
}


/* event_send_all_later_handler -- actually send events as needed */
static void event_send_all_later_handler(void *eloop_data, void *user_ctx)
{
	struct upnp_wps_device_sm *sm = user_ctx;
	struct subscription *s, *tmp;
	int nerrors = 0;

	sm->event_send_all_queued = 0;
	dl_list_for_each_safe(s, tmp, &sm->subscriptions, struct subscription,
			      list) {
		if (s->current_event == NULL /* not busy */ &&
		    !dl_list_empty(&s->event_queue) /* more to do */) {
			if (event_send_start(s))
				nerrors++;
		}
	}

	if (nerrors) {
		/* Try again later */
		event_send_all_later(sm);
	}
}


/* event_send_all_later -- schedule sending events to all subscribers
 * that need it.
 * This avoids two problems:
 * -- After getting a subscription, we should not send the first event
 *      until after our reply is fully queued to be sent back,
 * -- Possible stack depth or infinite recursion issues.
 */
void event_send_all_later(struct upnp_wps_device_sm *sm)
{
	/*
	 * The exact time in the future isn't too important. Waiting a bit
	 * might let us do several together.
	 */
	if (sm->event_send_all_queued)
		return;
	sm->event_send_all_queued = 1;
	eloop_register_timeout(EVENT_DELAY_SECONDS, EVENT_DELAY_MSEC,
			       event_send_all_later_handler, NULL, sm);
}


/* event_send_stop_all -- cleanup */
void event_send_stop_all(struct upnp_wps_device_sm *sm)
{
	if (sm->event_send_all_queued)
		eloop_cancel_timeout(event_send_all_later_handler, NULL, sm);
	sm->event_send_all_queued = 0;
}


/**
 * event_add - Add a new event to a queue
 * @s: Subscription
 * @data: Event data (is copied; caller retains ownership)
 * @probereq: Whether this is a Probe Request event
 * Returns: 0 on success, -1 on error, 1 on max event queue limit reached
 */
int event_add(struct subscription *s, const struct wpabuf *data, int probereq)
{
	struct wps_event_ *e;
	unsigned int len;

	len = dl_list_len(&s->event_queue);
	if (len >= MAX_EVENTS_QUEUED) {
		wpa_printf(MSG_DEBUG, "WPS UPnP: Too many events queued for "
			   "subscriber %p", s);
		if (probereq)
			return 1;

		/* Drop oldest entry to allow EAP event to be stored. */
		e = event_dequeue(s);
		if (!e)
			return 1;
		event_delete(e);
	}

	if (s->last_event_failed && probereq && len > 0) {
		/*
		 * Avoid queuing frames for subscribers that may have left
		 * without unsubscribing.
		 */
		wpa_printf(MSG_DEBUG, "WPS UPnP: Do not queue more Probe "
			   "Request frames for subscription %p since last "
			   "delivery failed", s);
		return -1;
	}

	e = os_zalloc(sizeof(*e));
	if (e == NULL)
		return -1;
	dl_list_init(&e->list);
	e->s = s;
	e->data = wpabuf_dup(data);
	if (e->data == NULL) {
		os_free(e);
		return -1;
	}
	e->subscriber_sequence = s->next_subscriber_sequence++;
	if (s->next_subscriber_sequence == 0)
		s->next_subscriber_sequence++;
	wpa_printf(MSG_DEBUG, "WPS UPnP: Queue event %p for subscriber %p "
		   "(queue len %u)", e, s, len + 1);
	dl_list_add_tail(&s->event_queue, &e->list);
	event_send_all_later(s->sm);
	return 0;
}
Commit	Line	Data
f620268f JM	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
3953627b	6	* Copyright (c) 2009-2010, Jouni Malinen <j@w1.fi>
f620268f JM	7	*
	8	* See wps_upnp.c for more details on licensing and code history.
	9	*/
	10
	11	#include "includes.h"
	12	#include <assert.h>
f620268f JM	13
	14	#include "common.h"
	15	#include "eloop.h"
	16	#include "uuid.h"
092794f4	17	#include "http_client.h"
915c1ba3	18	#include "wps_defs.h"
f620268f JM	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 */
dd50c2d4	34	#define MAX_FAILURES 10 /* Drop subscription after this many failures */
f620268f JM	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_ {
f1de40f7	49	struct dl_list list;
f620268f JM	50	struct subscription s; / parent */
f620268f JM	51	unsigned subscriber_sequence; /* which event for this subscription*/
f98b440c	52	unsigned int retry; /* which retry */
f620268f JM	53	struct subscr_addr addr; / address to connect to */
f620268f JM	54	struct wpabuf data; / event data to send */
092794f4	55	struct http_client *http_event;
f620268f JM	56	};
	57
	58
f620268f JM	59	/* event_clean -- clean sockets etc. of event
	60	* Leaves data, retry count etc. alone.
	61	*/
	62	static void event_clean(struct wps_event_ *e)
	63	{
092794f4	64	if (e->s->current_event == e)
f620268f	65	e->s->current_event = NULL;
092794f4 JM	66	http_client_free(e->http_event);
092794f4 JM	67	e->http_event = NULL;
f620268f JM	68	}
	69
	70
	71	/* event_delete -- delete single unqueued event
	72	* (be sure to dequeue first if need be)
	73	*/
b02ee4a2	74	static void event_delete(struct wps_event_ *e)
f620268f	75	{
3953627b	76	wpa_printf(MSG_DEBUG, "WPS UPnP: Delete event %p", e);
f620268f JM	77	event_clean(e);
	78	wpabuf_free(e->data);
	79	os_free(e);
	80	}
	81
	82
	83	/* event_dequeue -- get next event from the queue
	84	* Returns NULL if empty.
	85	*/
	86	static struct wps_event_ event_dequeue(struct subscription s)
	87	{
f1de40f7 JM	88	struct wps_event_ *e;
f1de40f7 JM	89	e = dl_list_first(&s->event_queue, struct wps_event_, list);
3953627b JM	90	if (e) {
	91	wpa_printf(MSG_DEBUG, "WPS UPnP: Dequeue event %p for "
	92	"subscription %p", e, s);
f1de40f7	93	dl_list_del(&e->list);
3953627b	94	}
f620268f JM	95	return e;
	96	}
	97
	98
f620268f JM	99	/* event_delete_all -- delete entire event queue and current event */
	100	void event_delete_all(struct subscription *s)
	101	{
	102	struct wps_event_ *e;
	103	while ((e = event_dequeue(s)) != NULL)
	104	event_delete(e);
	105	if (s->current_event) {
	106	event_delete(s->current_event);
	107	/* will set: s->current_event = NULL; */
	108	}
	109	}
	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	static void event_retry(struct wps_event_ *e, int do_next_address)
	118	{
	119	struct subscription *s = e->s;
	120	struct upnp_wps_device_sm *sm = s->sm;
	121
3953627b JM	122	wpa_printf(MSG_DEBUG, "WPS UPnP: Retry event %p for subscription %p",
3953627b JM	123	e, s);
f620268f JM	124	event_clean(e);
	125	/* will set: s->current_event = NULL; */
	126
3953627b	127	if (do_next_address) {
f620268f	128	e->retry++;
3953627b JM	129	wpa_printf(MSG_DEBUG, "WPS UPnP: Try address %d", e->retry);
3953627b JM	130	}
f98b440c	131	if (e->retry >= dl_list_len(&s->addr_list)) {
745f8b66 JM	132	wpa_printf(MSG_DEBUG, "WPS UPnP: Giving up on sending event "
745f8b66 JM	133	"for %s", e->addr->domain_and_port);
1f1d4df0	134	event_delete(e);
3904567d	135	s->last_event_failed = 1;
d1e17fbc JM	136	if (!dl_list_empty(&s->event_queue))
d1e17fbc JM	137	event_send_all_later(s->sm);
f620268f JM	138	return;
f620268f JM	139	}
f1de40f7	140	dl_list_add(&s->event_queue, &e->list);
f620268f JM	141	event_send_all_later(sm);
	142	}
	143
	144
092794f4	145	static struct wpabuf * event_build_message(struct wps_event_ *e)
f620268f	146	{
f620268f JM	147	struct wpabuf *buf;
	148	char *b;
	149
f620268f	150	buf = wpabuf_alloc(1000 + wpabuf_len(e->data));
092794f4 JM	151	if (buf == NULL)
092794f4 JM	152	return NULL;
f620268f JM	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"
	157	"NT: upnp:event\r\n"
	158	"NTS: upnp:propchange\r\n");
	159	wpabuf_put_str(buf, "SID: uuid:");
	160	b = wpabuf_put(buf, 0);
092794f4	161	uuid_bin2str(e->s->uuid, b, 80);
f620268f JM	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);
092794f4 JM	169	return buf;
092794f4 JM	170	}
f620268f	171
f620268f	172
dd50c2d4 JM	173	static void event_addr_failure(struct wps_event_ *e)
	174	{
	175	struct subscription *s = e->s;
	176
	177	e->addr->num_failures++;
	178	wpa_printf(MSG_DEBUG, "WPS UPnP: Failed to send event %p to %s "
	179	"(num_failures=%u)",
	180	e, e->addr->domain_and_port, e->addr->num_failures);
	181
	182	if (e->addr->num_failures < MAX_FAILURES) {
	183	/* Try other addresses, if available */
	184	event_retry(e, 1);
	185	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	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);
	196	e->addr = NULL;
	197
	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);
	204	return;
	205	}
	206
	207	/* Try other addresses, if available */
	208	event_retry(e, 0);
	209	}
	210
	211
092794f4 JM	212	static void event_http_cb(void ctx, struct http_client c,
	213	enum http_client_event event)
	214	{
	215	struct wps_event_ *e = ctx;
	216	struct subscription *s = e->s;
	217
3953627b JM	218	wpa_printf(MSG_DEBUG, "WPS UPnP: HTTP client callback: e=%p c=%p "
3953627b JM	219	"event=%d", e, c, event);
092794f4 JM	220	switch (event) {
	221	case HTTP_CLIENT_OK:
	222	wpa_printf(MSG_DEBUG,
3953627b JM	223	"WPS UPnP: Got event %p reply OK from %s",
3953627b JM	224	e, e->addr->domain_and_port);
dd50c2d4	225	e->addr->num_failures = 0;
3904567d	226	s->last_event_failed = 0;
092794f4	227	event_delete(e);
f620268f	228
092794f4	229	/* Schedule sending more if there is more to send */
f1de40f7	230	if (!dl_list_empty(&s->event_queue))
092794f4 JM	231	event_send_all_later(s->sm);
	232	break;
	233	case HTTP_CLIENT_FAILED:
dd50c2d4 JM	234	wpa_printf(MSG_DEBUG, "WPS UPnP: Event send failure");
	235	event_addr_failure(e);
	236	break;
092794f4	237	case HTTP_CLIENT_INVALID_REPLY:
dd50c2d4 JM	238	wpa_printf(MSG_DEBUG, "WPS UPnP: Invalid reply");
dd50c2d4 JM	239	event_addr_failure(e);
092794f4 JM	240	break;
	241	case HTTP_CLIENT_TIMEOUT:
	242	wpa_printf(MSG_DEBUG, "WPS UPnP: Event send timeout");
dd50c2d4 JM	243	event_addr_failure(e);
dd50c2d4 JM	244	break;
092794f4	245	}
f620268f JM	246	}
	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	static int event_send_start(struct subscription *s)
	270	{
	271	struct wps_event_ *e;
f98b440c	272	unsigned int itry;
092794f4	273	struct wpabuf *buf;
f620268f JM	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	*/
10fb1a98 JM	279	if (dl_list_empty(&s->addr_list))
	280	return -1;
	281	if (s->current_event)
	282	return -1;
	283	if (dl_list_empty(&s->event_queue))
	284	return -1;
f620268f JM	285
	286	s->current_event = e = event_dequeue(s);
	287
f98b440c JM	288	/* Use address according to number of retries */
	289	itry = 0;
	290	dl_list_for_each(e->addr, &s->addr_list, struct subscr_addr, list)
	291	if (itry++ == e->retry)
	292	break;
	293	if (itry < e->retry)
	294	return -1;
f620268f	295
092794f4 JM	296	buf = event_build_message(e);
092794f4 JM	297	if (buf == NULL) {
f620268f JM	298	event_retry(e, 0);
	299	return -1;
	300	}
092794f4 JM	301
	302	e->http_event = http_client_addr(&e->addr->saddr, buf, 0,
	303	event_http_cb, e);
	304	if (e->http_event == NULL) {
	305	wpabuf_free(buf);
f620268f JM	306	event_retry(e, 0);
	307	return -1;
	308	}
092794f4	309
f620268f JM	310	return 0;
	311	}
	312
	313
	314	/* event_send_all_later_handler -- actually send events as needed */
b02ee4a2	315	static void event_send_all_later_handler(void eloop_data, void user_ctx)
f620268f JM	316	{
f620268f JM	317	struct upnp_wps_device_sm *sm = user_ctx;
ec32c294	318	struct subscription s, tmp;
f620268f JM	319	int nerrors = 0;
	320
	321	sm->event_send_all_queued = 0;
ec32c294 JM	322	dl_list_for_each_safe(s, tmp, &sm->subscriptions, struct subscription,
ec32c294 JM	323	list) {
dd50c2d4 JM	324	if (s->current_event == NULL /* not busy */ &&
	325	!dl_list_empty(&s->event_queue) /* more to do */) {
	326	if (event_send_start(s))
	327	nerrors++;
f620268f	328	}
ec32c294	329	}
f620268f JM	330
	331	if (nerrors) {
	332	/* Try again later */
	333	event_send_all_later(sm);
	334	}
	335	}
	336
	337
	338	/* event_send_all_later -- schedule sending events to all subscribers
	339	* that need it.
	340	* This avoids two problems:
	341	* -- After getting a subscription, we should not send the first event
	342	* until after our reply is fully queued to be sent back,
	343	* -- Possible stack depth or infinite recursion issues.
	344	*/
	345	void event_send_all_later(struct upnp_wps_device_sm *sm)
	346	{
	347	/*
	348	* The exact time in the future isn't too important. Waiting a bit
	349	* might let us do several together.
	350	*/
	351	if (sm->event_send_all_queued)
	352	return;
	353	sm->event_send_all_queued = 1;
	354	eloop_register_timeout(EVENT_DELAY_SECONDS, EVENT_DELAY_MSEC,
	355	event_send_all_later_handler, NULL, sm);
	356	}
	357
	358
	359	/* event_send_stop_all -- cleanup */
	360	void event_send_stop_all(struct upnp_wps_device_sm *sm)
	361	{
	362	if (sm->event_send_all_queued)
	363	eloop_cancel_timeout(event_send_all_later_handler, NULL, sm);
	364	sm->event_send_all_queued = 0;
	365	}
	366
	367
	368	/**
	369	* event_add - Add a new event to a queue
	370	* @s: Subscription
	371	* @data: Event data (is copied; caller retains ownership)
3904567d	372	* @probereq: Whether this is a Probe Request event
8c3a2f11	373	* Returns: 0 on success, -1 on error, 1 on max event queue limit reached
f620268f	374	*/
3904567d	375	int event_add(struct subscription s, const struct wpabuf data, int probereq)
f620268f JM	376	{
f620268f JM	377	struct wps_event_ *e;
3953627b	378	unsigned int len;
f620268f	379
3953627b JM	380	len = dl_list_len(&s->event_queue);
3953627b JM	381	if (len >= MAX_EVENTS_QUEUED) {
f620268f	382	wpa_printf(MSG_DEBUG, "WPS UPnP: Too many events queued for "
3953627b	383	"subscriber %p", s);
f30e698c JM	384	if (probereq)
	385	return 1;
	386
	387	/* Drop oldest entry to allow EAP event to be stored. */
	388	e = event_dequeue(s);
	389	if (!e)
	390	return 1;
	391	event_delete(e);
f620268f JM	392	}
f620268f JM	393
3904567d JM	394	if (s->last_event_failed && probereq && len > 0) {
	395	/*
	396	* Avoid queuing frames for subscribers that may have left
	397	* without unsubscribing.
	398	*/
	399	wpa_printf(MSG_DEBUG, "WPS UPnP: Do not queue more Probe "
	400	"Request frames for subscription %p since last "
	401	"delivery failed", s);
	402	return -1;
	403	}
	404
f620268f JM	405	e = os_zalloc(sizeof(*e));
f620268f JM	406	if (e == NULL)
8c3a2f11	407	return -1;
f1de40f7	408	dl_list_init(&e->list);
f620268f	409	e->s = s;
f620268f JM	410	e->data = wpabuf_dup(data);
	411	if (e->data == NULL) {
	412	os_free(e);
8c3a2f11	413	return -1;
f620268f JM	414	}
	415	e->subscriber_sequence = s->next_subscriber_sequence++;
	416	if (s->next_subscriber_sequence == 0)
	417	s->next_subscriber_sequence++;
3953627b JM	418	wpa_printf(MSG_DEBUG, "WPS UPnP: Queue event %p for subscriber %p "
3953627b JM	419	"(queue len %u)", e, s, len + 1);
f1de40f7	420	dl_list_add_tail(&s->event_queue, &e->list);
f620268f JM	421	event_send_all_later(s->sm);
	422	return 0;
	423	}