libwebsockets/lib/core-net/wsi-timeout.c

/*
 * libwebsockets - small server side websockets and web server implementation
 *
 * Copyright (C) 2010 - 2019 Andy Green <andy@warmcat.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

#include "private-lib-core.h"

void
__lws_wsi_remove_from_sul(struct lws *wsi)
{
	//struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];

	//lwsl_notice("%s: wsi %p, to %p, hr %p\n", __func__, wsi,
	//		&wsi->sul_timeout.list, &wsi->sul_hrtimer.list);

	// lws_dll2_describe(&pt->pt_sul_owner, "pre-remove");
	lws_dll2_remove(&wsi->sul_timeout.list);
	lws_dll2_remove(&wsi->sul_hrtimer.list);
	lws_dll2_remove(&wsi->sul_validity.list);
	// lws_dll2_describe(&pt->pt_sul_owner, "post-remove");
}

/*
 * hrtimer
 */

static void
lws_sul_hrtimer_cb(lws_sorted_usec_list_t *sul)
{
	struct lws *wsi = lws_container_of(sul, struct lws, sul_hrtimer);

	if (wsi->protocol &&
	    wsi->protocol->callback(wsi, LWS_CALLBACK_TIMER,
				    wsi->user_space, NULL, 0))
		__lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS,
				     "hrtimer cb errored");
}

void
__lws_set_timer_usecs(struct lws *wsi, lws_usec_t us)
{
	struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];

	wsi->sul_hrtimer.cb = lws_sul_hrtimer_cb;
	__lws_sul_insert(&pt->pt_sul_owner, &wsi->sul_hrtimer, us);
}

LWS_VISIBLE void
lws_set_timer_usecs(struct lws *wsi, lws_usec_t usecs)
{
	__lws_set_timer_usecs(wsi, usecs);
}

/*
 * wsi timeout
 */

static void
lws_sul_wsitimeout_cb(lws_sorted_usec_list_t *sul)
{
	struct lws *wsi = lws_container_of(sul, struct lws, sul_timeout);
	struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];

	if (wsi->pending_timeout != PENDING_TIMEOUT_USER_OK)
		lws_stats_bump(pt, LWSSTATS_C_TIMEOUTS, 1);

	/* no need to log normal idle keepalive timeout */
//		if (wsi->pending_timeout != PENDING_TIMEOUT_HTTP_KEEPALIVE_IDLE)
#if defined(LWS_ROLE_H1) || defined(LWS_ROLE_H2)
	if (wsi->pending_timeout != PENDING_TIMEOUT_USER_OK)
		lwsl_info("wsi %p: TIMEDOUT WAITING on %d "
			  "(did hdr %d, ah %p, wl %d)\n",
			  (void *)wsi, wsi->pending_timeout,
			  wsi->hdr_parsing_completed, wsi->http.ah,
			  pt->http.ah_wait_list_length);
#if defined(LWS_WITH_CGI)
	if (wsi->http.cgi)
		lwsl_notice("CGI timeout: %s\n", wsi->http.cgi->summary);
#endif
#else
	if (wsi->pending_timeout != PENDING_TIMEOUT_USER_OK)
		lwsl_info("wsi %p: TIMEDOUT WAITING on %d ", (void *)wsi,
				wsi->pending_timeout);
#endif
	/* cgi timeout */
	if (wsi->pending_timeout != PENDING_TIMEOUT_HTTP_KEEPALIVE_IDLE)
		/*
		 * Since he failed a timeout, he already had a chance to
		 * do something and was unable to... that includes
		 * situations like half closed connections.  So process
		 * this "failed timeout" close as a violent death and
		 * don't try to do protocol cleanup like flush partials.
		 */
		wsi->socket_is_permanently_unusable = 1;
#if defined(LWS_WITH_CLIENT)
	if (lwsi_state(wsi) == LRS_WAITING_SSL)
		lws_inform_client_conn_fail(wsi,
			(void *)"Timed out waiting SSL", 21);
#endif

	__lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS, "timeout");
}

void
__lws_set_timeout(struct lws *wsi, enum pending_timeout reason, int secs)
{
	struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];

	wsi->sul_timeout.cb = lws_sul_wsitimeout_cb;
	__lws_sul_insert(&pt->pt_sul_owner, &wsi->sul_timeout,
			 ((lws_usec_t)secs) * LWS_US_PER_SEC);

	lwsl_debug("%s: %p: %d secs, reason %d\n", __func__, wsi, secs, reason);

	wsi->pending_timeout = reason;
}

void
lws_set_timeout(struct lws *wsi, enum pending_timeout reason, int secs)
{
	struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];

	lws_pt_lock(pt, __func__);
	lws_dll2_remove(&wsi->sul_timeout.list);
	lws_pt_unlock(pt);

	if (!secs)
		return;

	if (secs == LWS_TO_KILL_SYNC) {
		lwsl_debug("synchronously killing %p\n", wsi);
		lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS,
				   "to sync kill");
		return;
	}

	if (secs == LWS_TO_KILL_ASYNC)
		secs = 0;

	assert(!wsi->h2_stream_immortal);

	lws_pt_lock(pt, __func__);
	__lws_set_timeout(wsi, reason, secs);
	lws_pt_unlock(pt);
}

void
lws_set_timeout_us(struct lws *wsi, enum pending_timeout reason, lws_usec_t us)
{
	struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];

	lws_pt_lock(pt, __func__);
	lws_dll2_remove(&wsi->sul_timeout.list);
	lws_pt_unlock(pt);

	if (!us)
		return;

	lws_pt_lock(pt, __func__);
	__lws_sul_insert(&pt->pt_sul_owner, &wsi->sul_timeout, us);

	lwsl_debug("%s: %p: %llu us, reason %d\n", __func__, wsi,
		   (unsigned long long)us, reason);

	wsi->pending_timeout = reason;
	lws_pt_unlock(pt);
}

/* requires context + vh lock */

int
__lws_timed_callback_remove(struct lws_vhost *vh, struct lws_timed_vh_protocol *p)
{
	lws_start_foreach_llp_safe(struct lws_timed_vh_protocol **, pt,
			      vh->timed_vh_protocol_list, next) {
		if (*pt == p) {
			*pt = p->next;
			lws_dll2_remove(&p->sul.list);
			lws_free(p);

			return 0;
		}
	} lws_end_foreach_llp_safe(pt);

	return 1;
}

void
lws_sul_timed_callback_vh_protocol_cb(lws_sorted_usec_list_t *sul)
{
	struct lws_timed_vh_protocol *tvp = lws_container_of(sul,
					struct lws_timed_vh_protocol, sul);
	struct lws_context_per_thread *pt =
				&tvp->vhost->context->pt[tvp->tsi_req];

	pt->fake_wsi->context = tvp->vhost->context;

	pt->fake_wsi->vhost = tvp->vhost; /* not a real bound wsi */
	pt->fake_wsi->protocol = tvp->protocol;

	lwsl_debug("%s: timed cb: vh %s, protocol %s, reason %d\n", __func__,
		   tvp->vhost->name, tvp->protocol->name, tvp->reason);

	tvp->protocol->callback(pt->fake_wsi, tvp->reason, NULL, NULL, 0);

	__lws_timed_callback_remove(tvp->vhost, tvp);
}

int
lws_timed_callback_vh_protocol_us(struct lws_vhost *vh,
				  const struct lws_protocols *prot, int reason,
				  lws_usec_t us)
{
	struct lws_timed_vh_protocol *p = (struct lws_timed_vh_protocol *)
			lws_malloc(sizeof(*p), "timed_vh");

	if (!p)
		return 1;

	memset(p, 0, sizeof(*p));

	p->tsi_req = lws_pthread_self_to_tsi(vh->context);
	if (p->tsi_req < 0) /* not called from a service thread --> tsi 0 */
		p->tsi_req = 0;

	lws_context_lock(vh->context, __func__); /* context ----------------- */

	p->protocol = prot;
	p->reason = reason;
	p->vhost = vh;

	p->sul.cb = lws_sul_timed_callback_vh_protocol_cb;
	/* list is always at the very top of the sul */
	__lws_sul_insert(&vh->context->pt[p->tsi_req].pt_sul_owner,
			 (lws_sorted_usec_list_t *)&p->sul.list, us);

	// lwsl_notice("%s: %s.%s %d\n", __func__, vh->name, prot->name, secs);

	lws_vhost_lock(vh); /* vhost ---------------------------------------- */
	p->next = vh->timed_vh_protocol_list;
	vh->timed_vh_protocol_list = p;
	lws_vhost_unlock(vh); /* -------------------------------------- vhost */

	lws_context_unlock(vh->context); /* ------------------------- context */

	return 0;
}

int
lws_timed_callback_vh_protocol(struct lws_vhost *vh,
			       const struct lws_protocols *prot, int reason,
			       int secs)
{
	return lws_timed_callback_vh_protocol_us(vh, prot, reason,
					((lws_usec_t)secs) * LWS_US_PER_SEC);
}

static void
lws_validity_cb(lws_sorted_usec_list_t *sul)
{
	struct lws *wsi = lws_container_of(sul, struct lws, sul_validity);
	struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
	const lws_retry_bo_t *rbo = wsi->retry_policy;

	/* one of either the ping or hangup validity threshold was crossed */

	if (wsi->validity_hup) {
		lwsl_info("%s: wsi %p: validity too old\n", __func__, wsi);
		__lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS,
				     "validity timeout");
		return;
	}

	/* schedule a protocol-dependent ping */

	lwsl_info("%s: wsi %p: scheduling validity check\n", __func__, wsi);

	if (wsi->role_ops && wsi->role_ops->issue_keepalive)
		wsi->role_ops->issue_keepalive(wsi, 0);

	/*
	 * We arrange to come back here after the additional ping to hangup time
	 * and do the hangup, unless we get validated (by, eg, a PONG) and
	 * reset the timer
	 */

	assert(rbo->secs_since_valid_hangup > rbo->secs_since_valid_ping);

	wsi->validity_hup = 1;
	__lws_sul_insert(&pt->pt_sul_owner, &wsi->sul_validity,
			 ((uint64_t)rbo->secs_since_valid_hangup -
				 rbo->secs_since_valid_ping) * LWS_US_PER_SEC);
}

/*
 * The role calls this back to actually confirm validity on a particular wsi
 * (which may not be the original wsi)
 */

void
_lws_validity_confirmed_role(struct lws *wsi)
{
	struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
	const lws_retry_bo_t *rbo = wsi->retry_policy;

	if (!rbo || !rbo->secs_since_valid_hangup)
		return;

	wsi->validity_hup = 0;
	wsi->sul_validity.cb = lws_validity_cb;

	wsi->validity_hup = rbo->secs_since_valid_ping >=
			    rbo->secs_since_valid_hangup;

	lwsl_info("%s: wsi %p: setting validity timer %ds (hup %d)\n",
			__func__, wsi,
			wsi->validity_hup ? rbo->secs_since_valid_hangup :
					    rbo->secs_since_valid_ping,
			wsi->validity_hup);

	__lws_sul_insert(&pt->pt_sul_owner, &wsi->sul_validity,
			 ((uint64_t)(wsi->validity_hup ?
				rbo->secs_since_valid_hangup :
				rbo->secs_since_valid_ping)) * LWS_US_PER_SEC);
}

void
lws_validity_confirmed(struct lws *wsi)
{
	/*
	 * This may be a stream inside a muxed network connection... leave it
	 * to the role to figure out who actually needs to understand their
	 * validity was confirmed.
	 */
	if (wsi->role_ops && wsi->role_ops->issue_keepalive)
		wsi->role_ops->issue_keepalive(wsi, 1);
}