1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved.
5  * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved.
6  * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions are met:
10  *
11  * a) Redistributions of source code must retain the above copyright notice,
12  *    this list of conditions and the following disclaimer.
13  *
14  * b) Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in
16  *    the documentation and/or other materials provided with the distribution.
17  *
18  * c) Neither the name of Cisco Systems, Inc. nor the names of its
19  *    contributors may be used to endorse or promote products derived
20  *    from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
24  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
26  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
32  * THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #if defined(__FreeBSD__) && !defined(__Userspace__)
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD$");
38 #endif
39 
40 #define _IP_VHL
41 #include <netinet/sctp_os.h>
42 #include <netinet/sctp_pcb.h>
43 #ifdef INET6
44 #if defined(__FreeBSD__) && defined(__Userspace__)
45 #include <netinet6/sctp6_var.h>
46 #endif
47 #endif
48 #include <netinet/sctp_var.h>
49 #include <netinet/sctp_sysctl.h>
50 #include <netinet/sctp_timer.h>
51 #include <netinet/sctputil.h>
52 #include <netinet/sctp_output.h>
53 #include <netinet/sctp_header.h>
54 #include <netinet/sctp_indata.h>
55 #include <netinet/sctp_asconf.h>
56 #include <netinet/sctp_input.h>
57 #include <netinet/sctp.h>
58 #include <netinet/sctp_uio.h>
59 #if defined(INET) || defined(INET6)
60 #if !(defined(_WIN32) && defined(__Userspace__))
61 #include <netinet/udp.h>
62 #endif
63 #endif
64 
65 void
sctp_audit_retranmission_queue(struct sctp_association * asoc)66 sctp_audit_retranmission_queue(struct sctp_association *asoc)
67 {
68 	struct sctp_tmit_chunk *chk;
69 
70 	SCTPDBG(SCTP_DEBUG_TIMER4, "Audit invoked on send queue cnt:%d onqueue:%d\n",
71 			asoc->sent_queue_retran_cnt,
72 			asoc->sent_queue_cnt);
73 	asoc->sent_queue_retran_cnt = 0;
74 	asoc->sent_queue_cnt = 0;
75 	TAILQ_FOREACH(chk, &asoc->sent_queue, sctp_next) {
76 		if (chk->sent == SCTP_DATAGRAM_RESEND) {
77 			sctp_ucount_incr(asoc->sent_queue_retran_cnt);
78 		}
79 		asoc->sent_queue_cnt++;
80 	}
81 	TAILQ_FOREACH(chk, &asoc->control_send_queue, sctp_next) {
82 		if (chk->sent == SCTP_DATAGRAM_RESEND) {
83 			sctp_ucount_incr(asoc->sent_queue_retran_cnt);
84 		}
85 	}
86 	TAILQ_FOREACH(chk, &asoc->asconf_send_queue, sctp_next) {
87 		if (chk->sent == SCTP_DATAGRAM_RESEND) {
88 			sctp_ucount_incr(asoc->sent_queue_retran_cnt);
89 		}
90 	}
91 	SCTPDBG(SCTP_DEBUG_TIMER4, "Audit completes retran:%d onqueue:%d\n",
92 		asoc->sent_queue_retran_cnt,
93 		asoc->sent_queue_cnt);
94 }
95 
96 static int
sctp_threshold_management(struct sctp_inpcb * inp,struct sctp_tcb * stcb,struct sctp_nets * net,uint16_t threshold)97 sctp_threshold_management(struct sctp_inpcb *inp, struct sctp_tcb *stcb,
98     struct sctp_nets *net, uint16_t threshold)
99 {
100 	if (net) {
101 		net->error_count++;
102 		SCTPDBG(SCTP_DEBUG_TIMER4, "Error count for %p now %d thresh:%d\n",
103 			(void *)net, net->error_count,
104 			net->failure_threshold);
105 		if (net->error_count > net->failure_threshold) {
106 			/* We had a threshold failure */
107 			if (net->dest_state & SCTP_ADDR_REACHABLE) {
108 				net->dest_state &= ~SCTP_ADDR_REACHABLE;
109 				net->dest_state &= ~SCTP_ADDR_REQ_PRIMARY;
110 				net->dest_state &= ~SCTP_ADDR_PF;
111 				sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_DOWN,
112 				    stcb, 0,
113 				    (void *)net, SCTP_SO_NOT_LOCKED);
114 			}
115 		} else if ((net->pf_threshold < net->failure_threshold) &&
116 		           (net->error_count > net->pf_threshold)) {
117 			if (!(net->dest_state & SCTP_ADDR_PF)) {
118 				net->dest_state |= SCTP_ADDR_PF;
119 				net->last_active = sctp_get_tick_count();
120 				sctp_send_hb(stcb, net, SCTP_SO_NOT_LOCKED);
121 				sctp_timer_stop(SCTP_TIMER_TYPE_HEARTBEAT,
122 				                inp, stcb, net,
123 				                SCTP_FROM_SCTP_TIMER + SCTP_LOC_1);
124 				sctp_timer_start(SCTP_TIMER_TYPE_HEARTBEAT, inp, stcb, net);
125 			}
126 		}
127 	}
128 	if (stcb == NULL)
129 		return (0);
130 
131 	if (net) {
132 		if ((net->dest_state & SCTP_ADDR_UNCONFIRMED) == 0) {
133 			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
134 				sctp_misc_ints(SCTP_THRESHOLD_INCR,
135 					       stcb->asoc.overall_error_count,
136 					       (stcb->asoc.overall_error_count+1),
137 					       SCTP_FROM_SCTP_TIMER,
138 					       __LINE__);
139 			}
140 			stcb->asoc.overall_error_count++;
141 		}
142 	} else {
143 		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
144 			sctp_misc_ints(SCTP_THRESHOLD_INCR,
145 				       stcb->asoc.overall_error_count,
146 				       (stcb->asoc.overall_error_count+1),
147 				       SCTP_FROM_SCTP_TIMER,
148 				       __LINE__);
149 		}
150 		stcb->asoc.overall_error_count++;
151 	}
152 	SCTPDBG(SCTP_DEBUG_TIMER4, "Overall error count for %p now %d thresh:%u state:%x\n",
153 		(void *)&stcb->asoc, stcb->asoc.overall_error_count,
154 		(uint32_t)threshold,
155 		((net == NULL) ? (uint32_t) 0 : (uint32_t) net->dest_state));
156 	/*
157 	 * We specifically do not do >= to give the assoc one more change
158 	 * before we fail it.
159 	 */
160 	if (stcb->asoc.overall_error_count > threshold) {
161 		/* Abort notification sends a ULP notify */
162 		struct mbuf *op_err;
163 
164 		op_err = sctp_generate_cause(SCTP_BASE_SYSCTL(sctp_diag_info_code),
165 		                             "Association error counter exceeded");
166 		inp->last_abort_code = SCTP_FROM_SCTP_TIMER + SCTP_LOC_2;
167 		sctp_abort_an_association(inp, stcb, op_err, true, SCTP_SO_NOT_LOCKED);
168 		return (1);
169 	}
170 	return (0);
171 }
172 
173 /*
174  * sctp_find_alternate_net() returns a non-NULL pointer as long as there
175  * exists nets, which are not being deleted.
176  */
177 struct sctp_nets *
sctp_find_alternate_net(struct sctp_tcb * stcb,struct sctp_nets * net,int mode)178 sctp_find_alternate_net(struct sctp_tcb *stcb,
179     struct sctp_nets *net,
180     int mode)
181 {
182 	/* Find and return an alternate network if possible */
183 	struct sctp_nets *alt, *mnet, *min_errors_net = NULL , *max_cwnd_net = NULL;
184 	bool looped;
185 	/* JRS 5/14/07 - Initialize min_errors to an impossible value. */
186 	int min_errors = -1;
187 	uint32_t max_cwnd = 0;
188 
189 	if (stcb->asoc.numnets == 1) {
190 		/* No selection can be made. */
191 		return (TAILQ_FIRST(&stcb->asoc.nets));
192 	}
193 	/*
194 	 * JRS 5/14/07 - If mode is set to 2, use the CMT PF find alternate net algorithm.
195 	 * This algorithm chooses the active destination (not in PF state) with the largest
196 	 * cwnd value. If all destinations are in PF state, unreachable, or unconfirmed, choose
197 	 * the desination that is in PF state with the lowest error count. In case of a tie,
198 	 * choose the destination that was most recently active.
199 	 */
200 	if (mode == 2) {
201 		TAILQ_FOREACH(mnet, &stcb->asoc.nets, sctp_next) {
202 			/* JRS 5/14/07 - If the destination is unreachable or unconfirmed, skip it. */
203 			if (((mnet->dest_state & SCTP_ADDR_REACHABLE) != SCTP_ADDR_REACHABLE) ||
204 			    (mnet->dest_state & SCTP_ADDR_UNCONFIRMED)) {
205 				continue;
206 			}
207 			/*
208 			 * JRS 5/14/07 -  If the destination is reachable but in PF state, compare
209 			 *  the error count of the destination to the minimum error count seen thus far.
210 			 *  Store the destination with the lower error count.  If the error counts are
211 			 *  equal, store the destination that was most recently active.
212 			 */
213 			if (mnet->dest_state & SCTP_ADDR_PF) {
214 				/*
215 				 * JRS 5/14/07 - If the destination under consideration is the current
216 				 *  destination, work as if the error count is one higher.  The
217 				 *  actual error count will not be incremented until later in the
218 				 *  t3 handler.
219 				 */
220 				if (mnet == net) {
221 					if (min_errors == -1) {
222 						min_errors = mnet->error_count + 1;
223 						min_errors_net = mnet;
224 					} else if (mnet->error_count + 1 < min_errors) {
225 						min_errors = mnet->error_count + 1;
226 						min_errors_net = mnet;
227 					} else if (mnet->error_count + 1 == min_errors
228 								&& mnet->last_active > min_errors_net->last_active) {
229 						min_errors_net = mnet;
230 						min_errors = mnet->error_count + 1;
231 					}
232 					continue;
233 				} else {
234 					if (min_errors == -1) {
235 						min_errors = mnet->error_count;
236 						min_errors_net = mnet;
237 					} else if (mnet->error_count < min_errors) {
238 						min_errors = mnet->error_count;
239 						min_errors_net = mnet;
240 					} else if (mnet->error_count == min_errors
241 								&& mnet->last_active > min_errors_net->last_active) {
242 						min_errors_net = mnet;
243 						min_errors = mnet->error_count;
244 					}
245 					continue;
246 				}
247 			}
248 			/*
249 			 * JRS 5/14/07 - If the destination is reachable and not in PF state, compare the
250 			 *  cwnd of the destination to the highest cwnd seen thus far.  Store the
251 			 *  destination with the higher cwnd value.  If the cwnd values are equal,
252 			 *  randomly choose one of the two destinations.
253 			 */
254 			if (max_cwnd < mnet->cwnd) {
255 				max_cwnd_net = mnet;
256 				max_cwnd = mnet->cwnd;
257 			} else if (max_cwnd == mnet->cwnd) {
258 				uint32_t rndval;
259 				uint8_t this_random;
260 
261 				if (stcb->asoc.hb_random_idx > 3) {
262 					rndval = sctp_select_initial_TSN(&stcb->sctp_ep->sctp_ep);
263 					memcpy(stcb->asoc.hb_random_values, &rndval, sizeof(stcb->asoc.hb_random_values));
264 					this_random = stcb->asoc.hb_random_values[0];
265 					stcb->asoc.hb_random_idx++;
266 					stcb->asoc.hb_ect_randombit = 0;
267 				} else {
268 					this_random = stcb->asoc.hb_random_values[stcb->asoc.hb_random_idx];
269 					stcb->asoc.hb_random_idx++;
270 					stcb->asoc.hb_ect_randombit = 0;
271 				}
272 				if (this_random % 2 == 1) {
273 					max_cwnd_net = mnet;
274 					max_cwnd = mnet->cwnd; /* Useless? */
275 				}
276 			}
277 		}
278 		if (max_cwnd_net == NULL) {
279 			if (min_errors_net == NULL) {
280 				return (net);
281 			}
282 			return (min_errors_net);
283 		} else {
284 			return (max_cwnd_net);
285 		}
286 	} /* JRS 5/14/07 - If mode is set to 1, use the CMT policy for choosing an alternate net. */
287 	else if (mode == 1) {
288 		TAILQ_FOREACH(mnet, &stcb->asoc.nets, sctp_next) {
289 			if (((mnet->dest_state & SCTP_ADDR_REACHABLE) != SCTP_ADDR_REACHABLE) ||
290 			    (mnet->dest_state & SCTP_ADDR_UNCONFIRMED)) {
291 				/*
292 				 * will skip ones that are not-reachable or
293 				 * unconfirmed
294 				 */
295 				continue;
296 			}
297 			if (max_cwnd < mnet->cwnd) {
298 				max_cwnd_net = mnet;
299 				max_cwnd = mnet->cwnd;
300 			} else if (max_cwnd == mnet->cwnd) {
301 				uint32_t rndval;
302 				uint8_t this_random;
303 
304 				if (stcb->asoc.hb_random_idx > 3) {
305 					rndval = sctp_select_initial_TSN(&stcb->sctp_ep->sctp_ep);
306 					memcpy(stcb->asoc.hb_random_values, &rndval,
307 					    sizeof(stcb->asoc.hb_random_values));
308 					this_random = stcb->asoc.hb_random_values[0];
309 					stcb->asoc.hb_random_idx = 0;
310 					stcb->asoc.hb_ect_randombit = 0;
311 				} else {
312 					this_random = stcb->asoc.hb_random_values[stcb->asoc.hb_random_idx];
313 					stcb->asoc.hb_random_idx++;
314 					stcb->asoc.hb_ect_randombit = 0;
315 				}
316 				if (this_random % 2) {
317 					max_cwnd_net = mnet;
318 					max_cwnd = mnet->cwnd;
319 				}
320 			}
321 		}
322 		if (max_cwnd_net) {
323 			return (max_cwnd_net);
324 		}
325 	}
326 	/* Look for an alternate net, which is active. */
327 	if ((net != NULL) && ((net->dest_state & SCTP_ADDR_BEING_DELETED) == 0)) {
328 		alt = TAILQ_NEXT(net, sctp_next);
329 	} else {
330 		alt = TAILQ_FIRST(&stcb->asoc.nets);
331 	}
332 	looped = false;
333 	for (;;) {
334 		if (alt == NULL) {
335 			if (!looped) {
336 				alt = TAILQ_FIRST(&stcb->asoc.nets);
337 				looped = true;
338 			}
339 			/* Definitely out of candidates. */
340 			if (alt == NULL) {
341 				break;
342 			}
343 		}
344 #if defined(__FreeBSD__) && !defined(__Userspace__)
345 		if (alt->ro.ro_nh == NULL) {
346 #else
347 		if (alt->ro.ro_rt == NULL) {
348 #endif
349 			if (alt->ro._s_addr) {
350 				sctp_free_ifa(alt->ro._s_addr);
351 				alt->ro._s_addr = NULL;
352 			}
353 			alt->src_addr_selected = 0;
354 		}
355 		if (((alt->dest_state & SCTP_ADDR_REACHABLE) == SCTP_ADDR_REACHABLE) &&
356 #if defined(__FreeBSD__) && !defined(__Userspace__)
357 		    (alt->ro.ro_nh != NULL) &&
358 #else
359 		    (alt->ro.ro_rt != NULL) &&
360 #endif
361 		    (!(alt->dest_state & SCTP_ADDR_UNCONFIRMED)) &&
362 		    (alt != net)) {
363 			/* Found an alternate net, which is reachable. */
364 			break;
365 		}
366 		alt = TAILQ_NEXT(alt, sctp_next);
367 	}
368 
369 	if (alt == NULL) {
370 		/*
371 		 * In case no active alternate net has been found, look for
372 		 * an alternate net, which is confirmed.
373 		 */
374 		if ((net != NULL) && ((net->dest_state & SCTP_ADDR_BEING_DELETED) == 0)) {
375 			alt = TAILQ_NEXT(net, sctp_next);
376 		} else {
377 			alt = TAILQ_FIRST(&stcb->asoc.nets);
378 		}
379 		looped = false;
380 		for (;;) {
381 			if (alt == NULL) {
382 				if (!looped) {
383 					alt = TAILQ_FIRST(&stcb->asoc.nets);
384 					looped = true;
385 				}
386 				/* Definitely out of candidates. */
387 				if (alt == NULL) {
388 					break;
389 				}
390 			}
391 			if ((!(alt->dest_state & SCTP_ADDR_UNCONFIRMED)) &&
392 			    (alt != net)) {
393 				/* Found an alternate net, which is confirmed. */
394 				break;
395 			}
396 			alt = TAILQ_NEXT(alt, sctp_next);
397 		}
398 	}
399 	if (alt == NULL) {
400 		/*
401 		 * In case no confirmed alternate net has been found, just
402 		 * return net, if it is not being deleted. In the other case
403 		 * just return the first net.
404 		 */
405 		if ((net != NULL) && ((net->dest_state & SCTP_ADDR_BEING_DELETED) == 0)) {
406 			alt = net;
407 		}
408 		if (alt == NULL) {
409 			alt = TAILQ_FIRST(&stcb->asoc.nets);
410 		}
411 	}
412 	return (alt);
413 }
414 
415 static void
416 sctp_backoff_on_timeout(struct sctp_tcb *stcb,
417     struct sctp_nets *net,
418     int win_probe,
419     int num_marked, int num_abandoned)
420 {
421 	if (net->RTO == 0) {
422 		if (net->RTO_measured) {
423 			net->RTO = stcb->asoc.minrto;
424 		} else {
425 			net->RTO = stcb->asoc.initial_rto;
426 		}
427 	}
428 	net->RTO <<= 1;
429 	if (net->RTO > stcb->asoc.maxrto) {
430 		net->RTO = stcb->asoc.maxrto;
431 	}
432 	if ((win_probe == 0) && (num_marked || num_abandoned)) {
433 		/* We don't apply penalty to window probe scenarios */
434 		/* JRS - Use the congestion control given in the CC module */
435 		stcb->asoc.cc_functions.sctp_cwnd_update_after_timeout(stcb, net);
436 	}
437 }
438 
439 #ifndef INVARIANTS
440 static void
441 sctp_recover_sent_list(struct sctp_tcb *stcb)
442 {
443 	struct sctp_tmit_chunk *chk, *nchk;
444 	struct sctp_association *asoc;
445 
446 	asoc = &stcb->asoc;
447 	TAILQ_FOREACH_SAFE(chk, &asoc->sent_queue, sctp_next, nchk) {
448 		if (SCTP_TSN_GE(asoc->last_acked_seq, chk->rec.data.tsn)) {
449 			SCTP_PRINTF("Found chk:%p tsn:%x <= last_acked_seq:%x\n",
450 			            (void *)chk, chk->rec.data.tsn, asoc->last_acked_seq);
451 			if (chk->sent != SCTP_DATAGRAM_NR_ACKED) {
452 				if (asoc->strmout[chk->rec.data.sid].chunks_on_queues > 0) {
453 					asoc->strmout[chk->rec.data.sid].chunks_on_queues--;
454 				}
455 			}
456 			if ((asoc->strmout[chk->rec.data.sid].chunks_on_queues == 0) &&
457 			    (asoc->strmout[chk->rec.data.sid].state == SCTP_STREAM_RESET_PENDING) &&
458 			    TAILQ_EMPTY(&asoc->strmout[chk->rec.data.sid].outqueue)) {
459 				asoc->trigger_reset = 1;
460 			}
461 			TAILQ_REMOVE(&asoc->sent_queue, chk, sctp_next);
462 			if (PR_SCTP_ENABLED(chk->flags)) {
463 				if (asoc->pr_sctp_cnt != 0)
464 					asoc->pr_sctp_cnt--;
465 			}
466 			if (chk->data) {
467 				/*sa_ignore NO_NULL_CHK*/
468 				sctp_free_bufspace(stcb, asoc, chk, 1);
469 				sctp_m_freem(chk->data);
470 				chk->data = NULL;
471 				if (asoc->prsctp_supported && PR_SCTP_BUF_ENABLED(chk->flags)) {
472 					asoc->sent_queue_cnt_removeable--;
473 				}
474 			}
475 			asoc->sent_queue_cnt--;
476 			sctp_free_a_chunk(stcb, chk, SCTP_SO_NOT_LOCKED);
477 		}
478 	}
479 	SCTP_PRINTF("after recover order is as follows\n");
480 	TAILQ_FOREACH(chk, &asoc->sent_queue, sctp_next) {
481 		SCTP_PRINTF("chk:%p TSN:%x\n", (void *)chk, chk->rec.data.tsn);
482 	}
483 }
484 #endif
485 
486 static int
487 sctp_mark_all_for_resend(struct sctp_tcb *stcb,
488     struct sctp_nets *net,
489     struct sctp_nets *alt,
490     int window_probe,
491     int *num_marked,
492     int *num_abandoned)
493 {
494 
495 	/*
496 	 * Mark all chunks (well not all) that were sent to *net for
497 	 * retransmission. Move them to alt for there destination as well...
498 	 * We only mark chunks that have been outstanding long enough to
499 	 * have received feed-back.
500 	 */
501 	struct sctp_tmit_chunk *chk, *nchk;
502 	struct sctp_nets *lnets;
503 	struct timeval now, min_wait, tv;
504 	int cur_rto;
505 	int cnt_abandoned;
506 	int audit_tf, num_mk, fir;
507 	unsigned int cnt_mk;
508 	uint32_t orig_flight, orig_tf;
509 	uint32_t tsnlast, tsnfirst;
510 	int recovery_cnt = 0;
511 
512 	/* none in flight now */
513 	audit_tf = 0;
514 	fir = 0;
515 	/*
516 	 * figure out how long a data chunk must be pending before we can
517 	 * mark it ..
518 	 */
519 	(void)SCTP_GETTIME_TIMEVAL(&now);
520 	/* get cur rto in micro-seconds */
521 	cur_rto = (net->lastsa >> SCTP_RTT_SHIFT) + net->lastsv;
522 	cur_rto *= 1000;
523 	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
524 		sctp_log_fr(cur_rto,
525 			    stcb->asoc.peers_rwnd,
526 			    window_probe,
527 			    SCTP_FR_T3_MARK_TIME);
528 		sctp_log_fr(net->flight_size, 0, 0, SCTP_FR_CWND_REPORT);
529 		sctp_log_fr(net->flight_size, net->cwnd, stcb->asoc.total_flight, SCTP_FR_CWND_REPORT);
530 	}
531 	tv.tv_sec = cur_rto / 1000000;
532 	tv.tv_usec = cur_rto % 1000000;
533 #if !(defined(__FreeBSD__) && !defined(__Userspace__))
534 	timersub(&now, &tv, &min_wait);
535 #else
536 	min_wait = now;
537 	timevalsub(&min_wait, &tv);
538 #endif
539 	if (min_wait.tv_sec < 0 || min_wait.tv_usec < 0) {
540 		/*
541 		 * if we hit here, we don't have enough seconds on the clock
542 		 * to account for the RTO. We just let the lower seconds be
543 		 * the bounds and don't worry about it. This may mean we
544 		 * will mark a lot more than we should.
545 		 */
546 		min_wait.tv_sec = min_wait.tv_usec = 0;
547 	}
548 	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
549 		sctp_log_fr(cur_rto, (uint32_t)now.tv_sec, now.tv_usec, SCTP_FR_T3_MARK_TIME);
550 		sctp_log_fr(0, (uint32_t)min_wait.tv_sec, min_wait.tv_usec, SCTP_FR_T3_MARK_TIME);
551 	}
552 	/*
553 	 * Our rwnd will be incorrect here since we are not adding back the
554 	 * cnt * mbuf but we will fix that down below.
555 	 */
556 	orig_flight = net->flight_size;
557 	orig_tf = stcb->asoc.total_flight;
558 
559 	net->fast_retran_ip = 0;
560 	/* Now on to each chunk */
561 	cnt_abandoned = 0;
562 	num_mk = cnt_mk = 0;
563 	tsnfirst = tsnlast = 0;
564 #ifndef INVARIANTS
565  start_again:
566 #endif
567 	TAILQ_FOREACH_SAFE(chk, &stcb->asoc.sent_queue, sctp_next, nchk) {
568 		if (SCTP_TSN_GE(stcb->asoc.last_acked_seq, chk->rec.data.tsn)) {
569 			/* Strange case our list got out of order? */
570 			SCTP_PRINTF("Our list is out of order? last_acked:%x chk:%x\n",
571 			            (unsigned int)stcb->asoc.last_acked_seq, (unsigned int)chk->rec.data.tsn);
572 			recovery_cnt++;
573 #ifdef INVARIANTS
574 			panic("last acked >= chk on sent-Q");
575 #else
576 			SCTP_PRINTF("Recover attempts a restart cnt:%d\n", recovery_cnt);
577 			sctp_recover_sent_list(stcb);
578 			if (recovery_cnt < 10) {
579 				goto start_again;
580 			} else {
581 				SCTP_PRINTF("Recovery fails %d times??\n", recovery_cnt);
582 			}
583 #endif
584 		}
585 		if ((chk->whoTo == net) && (chk->sent < SCTP_DATAGRAM_ACKED)) {
586 			/*
587 			 * found one to mark: If it is less than
588 			 * DATAGRAM_ACKED it MUST not be a skipped or marked
589 			 * TSN but instead one that is either already set
590 			 * for retransmission OR one that needs
591 			 * retransmission.
592 			 */
593 
594 			/* validate its been outstanding long enough */
595 			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
596 				sctp_log_fr(chk->rec.data.tsn,
597 					    (uint32_t)chk->sent_rcv_time.tv_sec,
598 					    chk->sent_rcv_time.tv_usec,
599 					    SCTP_FR_T3_MARK_TIME);
600 			}
601 			if ((chk->sent_rcv_time.tv_sec > min_wait.tv_sec) && (window_probe == 0)) {
602 				/*
603 				 * we have reached a chunk that was sent
604 				 * some seconds past our min.. forget it we
605 				 * will find no more to send.
606 				 */
607 				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
608 					sctp_log_fr(0,
609 						    (uint32_t)chk->sent_rcv_time.tv_sec,
610 						    chk->sent_rcv_time.tv_usec,
611 						    SCTP_FR_T3_STOPPED);
612 				}
613 				continue;
614 			} else if ((chk->sent_rcv_time.tv_sec == min_wait.tv_sec) &&
615 				   (window_probe == 0)) {
616 				/*
617 				 * we must look at the micro seconds to
618 				 * know.
619 				 */
620 				if (chk->sent_rcv_time.tv_usec >= min_wait.tv_usec) {
621 					/*
622 					 * ok it was sent after our boundary
623 					 * time.
624 					 */
625 					continue;
626 				}
627 			}
628 			if (stcb->asoc.prsctp_supported && PR_SCTP_TTL_ENABLED(chk->flags)) {
629 				/* Is it expired? */
630 #if !(defined(__FreeBSD__) && !defined(__Userspace__))
631 				if (timercmp(&now, &chk->rec.data.timetodrop, >)) {
632 #else
633 				if (timevalcmp(&now, &chk->rec.data.timetodrop, >)) {
634 #endif
635 					/* Yes so drop it */
636 					if (chk->data) {
637 						(void)sctp_release_pr_sctp_chunk(stcb,
638 										 chk,
639 										 1,
640 										 SCTP_SO_NOT_LOCKED);
641 						cnt_abandoned++;
642 					}
643 					continue;
644 				}
645 			}
646 			if (stcb->asoc.prsctp_supported && PR_SCTP_RTX_ENABLED(chk->flags)) {
647 				/* Has it been retransmitted tv_sec times? */
648 				if (chk->snd_count > chk->rec.data.timetodrop.tv_sec) {
649 					if (chk->data) {
650 						(void)sctp_release_pr_sctp_chunk(stcb,
651 										 chk,
652 										 1,
653 										 SCTP_SO_NOT_LOCKED);
654 						cnt_abandoned++;
655 					}
656 					continue;
657 				}
658 			}
659 			if (chk->sent < SCTP_DATAGRAM_RESEND) {
660 				sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
661 				num_mk++;
662 				if (fir == 0) {
663 					fir = 1;
664 					tsnfirst = chk->rec.data.tsn;
665 				}
666 				tsnlast = chk->rec.data.tsn;
667 				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
668 					sctp_log_fr(chk->rec.data.tsn, chk->snd_count,
669 						    0, SCTP_FR_T3_MARKED);
670 				}
671 
672 				if (chk->rec.data.chunk_was_revoked) {
673 					/* deflate the cwnd */
674 					chk->whoTo->cwnd -= chk->book_size;
675 					chk->rec.data.chunk_was_revoked = 0;
676 				}
677 				net->marked_retrans++;
678 				stcb->asoc.marked_retrans++;
679 				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FLIGHT_LOGGING_ENABLE) {
680 					sctp_misc_ints(SCTP_FLIGHT_LOG_DOWN_RSND_TO,
681 						       chk->whoTo->flight_size,
682 						       chk->book_size,
683 						       (uint32_t)(uintptr_t)chk->whoTo,
684 						       chk->rec.data.tsn);
685 				}
686 				sctp_flight_size_decrease(chk);
687 				sctp_total_flight_decrease(stcb, chk);
688 				stcb->asoc.peers_rwnd += chk->send_size;
689 				stcb->asoc.peers_rwnd += SCTP_BASE_SYSCTL(sctp_peer_chunk_oh);
690 			}
691 			chk->sent = SCTP_DATAGRAM_RESEND;
692 			chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
693 			SCTP_STAT_INCR(sctps_markedretrans);
694 
695 			/* reset the TSN for striking and other FR stuff */
696 			chk->rec.data.doing_fast_retransmit = 0;
697 			/* Clear any time so NO RTT is being done */
698 
699 			if (chk->do_rtt) {
700 				if (chk->whoTo->rto_needed == 0) {
701 					chk->whoTo->rto_needed = 1;
702 				}
703 			}
704 			chk->do_rtt = 0;
705 			if (alt != net) {
706 				sctp_free_remote_addr(chk->whoTo);
707 				chk->no_fr_allowed = 1;
708 				chk->whoTo = alt;
709 				atomic_add_int(&alt->ref_count, 1);
710 			} else {
711 				chk->no_fr_allowed = 0;
712 				if (TAILQ_EMPTY(&stcb->asoc.send_queue)) {
713 					chk->rec.data.fast_retran_tsn = stcb->asoc.sending_seq;
714 				} else {
715 					chk->rec.data.fast_retran_tsn = (TAILQ_FIRST(&stcb->asoc.send_queue))->rec.data.tsn;
716 				}
717 			}
718 			/* CMT: Do not allow FRs on retransmitted TSNs.
719 			 */
720 			if (stcb->asoc.sctp_cmt_on_off > 0) {
721 				chk->no_fr_allowed = 1;
722 			}
723 #ifdef THIS_SHOULD_NOT_BE_DONE
724 		} else if (chk->sent == SCTP_DATAGRAM_ACKED) {
725 			/* remember highest acked one */
726 			could_be_sent = chk;
727 #endif
728 		}
729 		if (chk->sent == SCTP_DATAGRAM_RESEND) {
730 			cnt_mk++;
731 		}
732 	}
733 	if ((orig_flight - net->flight_size) != (orig_tf - stcb->asoc.total_flight)) {
734 		/* we did not subtract the same things? */
735 		audit_tf = 1;
736 	}
737 
738 	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
739 		sctp_log_fr(tsnfirst, tsnlast, num_mk, SCTP_FR_T3_TIMEOUT);
740 	}
741 #ifdef SCTP_DEBUG
742 	if (num_mk) {
743 		SCTPDBG(SCTP_DEBUG_TIMER1, "LAST TSN marked was %x\n",
744 			tsnlast);
745 		SCTPDBG(SCTP_DEBUG_TIMER1, "Num marked for retransmission was %d peer-rwd:%u\n",
746 			num_mk,
747 			stcb->asoc.peers_rwnd);
748 	}
749 #endif
750 	*num_marked = num_mk;
751 	*num_abandoned = cnt_abandoned;
752 	/* Now check for a ECN Echo that may be stranded And
753 	 * include the cnt_mk'd to have all resends in the
754 	 * control queue.
755 	 */
756 	TAILQ_FOREACH(chk, &stcb->asoc.control_send_queue, sctp_next) {
757 		if (chk->sent == SCTP_DATAGRAM_RESEND) {
758 			cnt_mk++;
759 		}
760 		if ((chk->whoTo == net) &&
761 		    (chk->rec.chunk_id.id == SCTP_ECN_ECHO)) {
762 			sctp_free_remote_addr(chk->whoTo);
763 			chk->whoTo = alt;
764 			if (chk->sent != SCTP_DATAGRAM_RESEND) {
765 				chk->sent = SCTP_DATAGRAM_RESEND;
766 				chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
767 				sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
768 				cnt_mk++;
769 			}
770 			atomic_add_int(&alt->ref_count, 1);
771 		}
772 	}
773 #ifdef THIS_SHOULD_NOT_BE_DONE
774 	if ((stcb->asoc.sent_queue_retran_cnt == 0) && (could_be_sent)) {
775 		/* fix it so we retransmit the highest acked anyway */
776 		sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
777 		cnt_mk++;
778 		could_be_sent->sent = SCTP_DATAGRAM_RESEND;
779 	}
780 #endif
781 	if (stcb->asoc.sent_queue_retran_cnt != cnt_mk) {
782 #ifdef INVARIANTS
783 		SCTP_PRINTF("Local Audit says there are %d for retran asoc cnt:%d we marked:%d this time\n",
784 			    cnt_mk, stcb->asoc.sent_queue_retran_cnt, num_mk);
785 #endif
786 #ifndef SCTP_AUDITING_ENABLED
787 		stcb->asoc.sent_queue_retran_cnt = cnt_mk;
788 #endif
789 	}
790 	if (audit_tf) {
791 		SCTPDBG(SCTP_DEBUG_TIMER4,
792 			"Audit total flight due to negative value net:%p\n",
793 			(void *)net);
794 		stcb->asoc.total_flight = 0;
795 		stcb->asoc.total_flight_count = 0;
796 		/* Clear all networks flight size */
797 		TAILQ_FOREACH(lnets, &stcb->asoc.nets, sctp_next) {
798 			lnets->flight_size = 0;
799 			SCTPDBG(SCTP_DEBUG_TIMER4,
800 				"Net:%p c-f cwnd:%d ssthresh:%d\n",
801 				(void *)lnets, lnets->cwnd, lnets->ssthresh);
802 		}
803 		TAILQ_FOREACH(chk, &stcb->asoc.sent_queue, sctp_next) {
804 			if (chk->sent < SCTP_DATAGRAM_RESEND) {
805 				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FLIGHT_LOGGING_ENABLE) {
806 					sctp_misc_ints(SCTP_FLIGHT_LOG_UP,
807 						       chk->whoTo->flight_size,
808 						       chk->book_size,
809 						       (uint32_t)(uintptr_t)chk->whoTo,
810 						       chk->rec.data.tsn);
811 				}
812 
813 				sctp_flight_size_increase(chk);
814 				sctp_total_flight_increase(stcb, chk);
815 			}
816 		}
817 	}
818 	/* We return 1 if we only have a window probe outstanding */
819 	return (0);
820 }
821 
822 int
823 sctp_t3rxt_timer(struct sctp_inpcb *inp,
824     struct sctp_tcb *stcb,
825     struct sctp_nets *net)
826 {
827 	struct sctp_nets *alt;
828 	int win_probe, num_mk, num_abandoned;
829 
830 	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
831 		sctp_log_fr(0, 0, 0, SCTP_FR_T3_TIMEOUT);
832 	}
833 	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
834 		struct sctp_nets *lnet;
835 
836 		TAILQ_FOREACH(lnet, &stcb->asoc.nets, sctp_next) {
837 			if (net == lnet) {
838 				sctp_log_cwnd(stcb, lnet, 1, SCTP_CWND_LOG_FROM_T3);
839 			} else {
840 				sctp_log_cwnd(stcb, lnet, 0, SCTP_CWND_LOG_FROM_T3);
841 			}
842 		}
843 	}
844 	/* Find an alternate and mark those for retransmission */
845 	if ((stcb->asoc.peers_rwnd == 0) &&
846 	    (stcb->asoc.total_flight < net->mtu)) {
847 		SCTP_STAT_INCR(sctps_timowindowprobe);
848 		win_probe = 1;
849 	} else {
850 		win_probe = 0;
851 	}
852 
853 	if (win_probe == 0) {
854 		/* We don't do normal threshold management on window probes */
855 		if (sctp_threshold_management(inp, stcb, net,
856 		    stcb->asoc.max_send_times)) {
857 			/* Association was destroyed */
858 			return (1);
859 		} else {
860 			if (net != stcb->asoc.primary_destination) {
861 				/* send a immediate HB if our RTO is stale */
862 				struct timeval now;
863 				uint32_t ms_goneby;
864 
865 				(void)SCTP_GETTIME_TIMEVAL(&now);
866 				if (net->last_sent_time.tv_sec) {
867 					ms_goneby = (uint32_t)(now.tv_sec - net->last_sent_time.tv_sec) * 1000;
868 				} else {
869 					ms_goneby = 0;
870 				}
871 				if ((net->dest_state & SCTP_ADDR_PF) == 0) {
872 					if ((ms_goneby > net->RTO) || (net->RTO == 0)) {
873 						/*
874 						 * no recent feed back in an RTO or
875 						 * more, request a RTT update
876 						 */
877 						sctp_send_hb(stcb, net, SCTP_SO_NOT_LOCKED);
878 					}
879 				}
880 			}
881 		}
882 	} else {
883 		/*
884 		 * For a window probe we don't penalize the net's but only
885 		 * the association. This may fail it if SACKs are not coming
886 		 * back. If sack's are coming with rwnd locked at 0, we will
887 		 * continue to hold things waiting for rwnd to raise
888 		 */
889 		if (sctp_threshold_management(inp, stcb, NULL,
890 		    stcb->asoc.max_send_times)) {
891 			/* Association was destroyed */
892 			return (1);
893 		}
894 	}
895 	if (stcb->asoc.sctp_cmt_on_off > 0) {
896 		if (net->pf_threshold < net->failure_threshold) {
897 			alt = sctp_find_alternate_net(stcb, net, 2);
898 		} else {
899 		        /*
900 			 * CMT: Using RTX_SSTHRESH policy for CMT.
901 			 * If CMT is being used, then pick dest with
902 			 * largest ssthresh for any retransmission.
903 			 */
904 			alt = sctp_find_alternate_net(stcb, net, 1);
905 			/*
906 			 * CUCv2: If a different dest is picked for
907 			 * the retransmission, then new
908 			 * (rtx-)pseudo_cumack needs to be tracked
909 			 * for orig dest. Let CUCv2 track new (rtx-)
910 			 * pseudo-cumack always.
911 			 */
912 			net->find_pseudo_cumack = 1;
913 			net->find_rtx_pseudo_cumack = 1;
914 		}
915 	} else {
916 		alt = sctp_find_alternate_net(stcb, net, 0);
917 	}
918 
919 	num_mk = 0;
920 	num_abandoned = 0;
921 	(void)sctp_mark_all_for_resend(stcb, net, alt, win_probe,
922 				      &num_mk, &num_abandoned);
923 	/* FR Loss recovery just ended with the T3. */
924 	stcb->asoc.fast_retran_loss_recovery = 0;
925 
926 	/* CMT FR loss recovery ended with the T3 */
927 	net->fast_retran_loss_recovery = 0;
928 	if ((stcb->asoc.cc_functions.sctp_cwnd_new_transmission_begins) &&
929 	    (net->flight_size == 0)) {
930 		(*stcb->asoc.cc_functions.sctp_cwnd_new_transmission_begins)(stcb, net);
931 	}
932 
933 	/*
934 	 * setup the sat loss recovery that prevents satellite cwnd advance.
935 	 */
936 	stcb->asoc.sat_t3_loss_recovery = 1;
937 	stcb->asoc.sat_t3_recovery_tsn = stcb->asoc.sending_seq;
938 
939 	/* Backoff the timer and cwnd */
940 	sctp_backoff_on_timeout(stcb, net, win_probe, num_mk, num_abandoned);
941 	if ((!(net->dest_state & SCTP_ADDR_REACHABLE)) ||
942 	    (net->dest_state & SCTP_ADDR_PF)) {
943 		/* Move all pending over too */
944 		sctp_move_chunks_from_net(stcb, net);
945 
946 		/* Get the address that failed, to
947 		 * force a new src address selecton and
948 		 * a route allocation.
949 		 */
950 		if (net->ro._s_addr) {
951 			sctp_free_ifa(net->ro._s_addr);
952 			net->ro._s_addr = NULL;
953 		}
954 		net->src_addr_selected = 0;
955 
956 		/* Force a route allocation too */
957 #if defined(__FreeBSD__) && !defined(__Userspace__)
958 		RO_NHFREE(&net->ro);
959 #else
960 		if (net->ro.ro_rt) {
961 			RTFREE(net->ro.ro_rt);
962 			net->ro.ro_rt = NULL;
963 		}
964 #endif
965 
966 		/* Was it our primary? */
967 		if ((stcb->asoc.primary_destination == net) && (alt != net)) {
968 			/*
969 			 * Yes, note it as such and find an alternate note:
970 			 * this means HB code must use this to resent the
971 			 * primary if it goes active AND if someone does a
972 			 * change-primary then this flag must be cleared
973 			 * from any net structures.
974 			 */
975 			if (stcb->asoc.alternate) {
976 				sctp_free_remote_addr(stcb->asoc.alternate);
977 			}
978 			stcb->asoc.alternate = alt;
979 			atomic_add_int(&stcb->asoc.alternate->ref_count, 1);
980 		}
981 	}
982 	/*
983 	 * Special case for cookie-echo'ed case, we don't do output but must
984 	 * await the COOKIE-ACK before retransmission
985 	 */
986 	if (SCTP_GET_STATE(stcb) == SCTP_STATE_COOKIE_ECHOED) {
987 		/*
988 		 * Here we just reset the timer and start again since we
989 		 * have not established the asoc
990 		 */
991 		sctp_timer_start(SCTP_TIMER_TYPE_SEND, inp, stcb, net);
992 		return (0);
993 	}
994 	if (stcb->asoc.prsctp_supported) {
995 		struct sctp_tmit_chunk *lchk;
996 
997 		lchk = sctp_try_advance_peer_ack_point(stcb, &stcb->asoc);
998 		/* C3. See if we need to send a Fwd-TSN */
999 		if (SCTP_TSN_GT(stcb->asoc.advanced_peer_ack_point, stcb->asoc.last_acked_seq)) {
1000 			send_forward_tsn(stcb, &stcb->asoc);
1001 			for (; lchk != NULL; lchk = TAILQ_NEXT(lchk, sctp_next)) {
1002 				if (lchk->whoTo != NULL) {
1003 					break;
1004 				}
1005 			}
1006 			if (lchk != NULL) {
1007 				/* Assure a timer is up */
1008 				sctp_timer_start(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep, stcb, lchk->whoTo);
1009 			}
1010 		}
1011 	}
1012 	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1013 		sctp_log_cwnd(stcb, net, net->cwnd, SCTP_CWND_LOG_FROM_RTX);
1014 	}
1015 	return (0);
1016 }
1017 
1018 int
1019 sctp_t1init_timer(struct sctp_inpcb *inp,
1020     struct sctp_tcb *stcb,
1021     struct sctp_nets *net)
1022 {
1023 	/* bump the thresholds */
1024 	if (stcb->asoc.delayed_connection) {
1025 		/*
1026 		 * special hook for delayed connection. The library did NOT
1027 		 * complete the rest of its sends.
1028 		 */
1029 		stcb->asoc.delayed_connection = 0;
1030 		sctp_send_initiate(inp, stcb, SCTP_SO_NOT_LOCKED);
1031 		return (0);
1032 	}
1033 	if (SCTP_GET_STATE(stcb) != SCTP_STATE_COOKIE_WAIT) {
1034 		return (0);
1035 	}
1036 	if (sctp_threshold_management(inp, stcb, net,
1037 	    stcb->asoc.max_init_times)) {
1038 		/* Association was destroyed */
1039 		return (1);
1040 	}
1041 	stcb->asoc.dropped_special_cnt = 0;
1042 	sctp_backoff_on_timeout(stcb, stcb->asoc.primary_destination, 1, 0, 0);
1043 	if (stcb->asoc.initial_init_rto_max < net->RTO) {
1044 		net->RTO = stcb->asoc.initial_init_rto_max;
1045 	}
1046 	if (stcb->asoc.numnets > 1) {
1047 		/* If we have more than one addr use it */
1048 		struct sctp_nets *alt;
1049 
1050 		alt = sctp_find_alternate_net(stcb, stcb->asoc.primary_destination, 0);
1051 		if (alt != stcb->asoc.primary_destination) {
1052 			sctp_move_chunks_from_net(stcb, stcb->asoc.primary_destination);
1053 			stcb->asoc.primary_destination = alt;
1054 		}
1055 	}
1056 	/* Send out a new init */
1057 	sctp_send_initiate(inp, stcb, SCTP_SO_NOT_LOCKED);
1058 	return (0);
1059 }
1060 
1061 /*
1062  * For cookie and asconf we actually need to find and mark for resend, then
1063  * increment the resend counter (after all the threshold management stuff of
1064  * course).
1065  */
1066 int
1067 sctp_cookie_timer(struct sctp_inpcb *inp,
1068     struct sctp_tcb *stcb,
1069     struct sctp_nets *net SCTP_UNUSED)
1070 {
1071 	struct sctp_nets *alt;
1072 	struct sctp_tmit_chunk *cookie;
1073 
1074 	/* first before all else we must find the cookie */
1075 	TAILQ_FOREACH(cookie, &stcb->asoc.control_send_queue, sctp_next) {
1076 		if (cookie->rec.chunk_id.id == SCTP_COOKIE_ECHO) {
1077 			break;
1078 		}
1079 	}
1080 	if (cookie == NULL) {
1081 		if (SCTP_GET_STATE(stcb) == SCTP_STATE_COOKIE_ECHOED) {
1082 			/* FOOBAR! */
1083 			struct mbuf *op_err;
1084 
1085 			op_err = sctp_generate_cause(SCTP_BASE_SYSCTL(sctp_diag_info_code),
1086 			                             "Cookie timer expired, but no cookie");
1087 			inp->last_abort_code = SCTP_FROM_SCTP_TIMER + SCTP_LOC_3;
1088 			sctp_abort_an_association(inp, stcb, op_err, false, SCTP_SO_NOT_LOCKED);
1089 		} else {
1090 #ifdef INVARIANTS
1091 			panic("Cookie timer expires in wrong state?");
1092 #else
1093 			SCTP_PRINTF("Strange in state %d not cookie-echoed yet c-e timer expires?\n", SCTP_GET_STATE(stcb));
1094 			return (0);
1095 #endif
1096 		}
1097 		return (0);
1098 	}
1099 	/* Ok we found the cookie, threshold management next */
1100 	if (sctp_threshold_management(inp, stcb, cookie->whoTo,
1101 	    stcb->asoc.max_init_times)) {
1102 		/* Assoc is over */
1103 		return (1);
1104 	}
1105 	/*
1106 	 * Cleared threshold management, now lets backoff the address
1107 	 * and select an alternate
1108 	 */
1109 	stcb->asoc.dropped_special_cnt = 0;
1110 	sctp_backoff_on_timeout(stcb, cookie->whoTo, 1, 0, 0);
1111 	alt = sctp_find_alternate_net(stcb, cookie->whoTo, 0);
1112 	if (alt != cookie->whoTo) {
1113 		sctp_free_remote_addr(cookie->whoTo);
1114 		cookie->whoTo = alt;
1115 		atomic_add_int(&alt->ref_count, 1);
1116 	}
1117 	/* Now mark the retran info */
1118 	if (cookie->sent != SCTP_DATAGRAM_RESEND) {
1119 		sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
1120 	}
1121 	cookie->sent = SCTP_DATAGRAM_RESEND;
1122 	cookie->flags |= CHUNK_FLAGS_FRAGMENT_OK;
1123 	/*
1124 	 * Now call the output routine to kick out the cookie again, Note we
1125 	 * don't mark any chunks for retran so that FR will need to kick in
1126 	 * to move these (or a send timer).
1127 	 */
1128 	return (0);
1129 }
1130 
1131 int
1132 sctp_strreset_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
1133 {
1134 	struct sctp_nets *alt, *net;
1135 	struct sctp_tmit_chunk *strrst = NULL, *chk = NULL;
1136 
1137 	if (stcb->asoc.stream_reset_outstanding == 0) {
1138 		return (0);
1139 	}
1140 	/* find the existing STRRESET, we use the seq number we sent out on */
1141 	(void)sctp_find_stream_reset(stcb, stcb->asoc.str_reset_seq_out, &strrst);
1142 	if (strrst == NULL) {
1143 		return (0);
1144 	}
1145 	net = strrst->whoTo;
1146 	/* do threshold management */
1147 	if (sctp_threshold_management(inp, stcb, net, stcb->asoc.max_send_times)) {
1148 		/* Assoc is over */
1149 		return (1);
1150 	}
1151 	/*
1152 	 * Cleared threshold management, now lets backoff the address
1153 	 * and select an alternate
1154 	 */
1155 	sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
1156 	alt = sctp_find_alternate_net(stcb, net, 0);
1157 	strrst->whoTo = alt;
1158 	atomic_add_int(&alt->ref_count, 1);
1159 
1160 	/* See if a ECN Echo is also stranded */
1161 	TAILQ_FOREACH(chk, &stcb->asoc.control_send_queue, sctp_next) {
1162 		if ((chk->whoTo == net) &&
1163 		    (chk->rec.chunk_id.id == SCTP_ECN_ECHO)) {
1164 			sctp_free_remote_addr(chk->whoTo);
1165 			if (chk->sent != SCTP_DATAGRAM_RESEND) {
1166 				chk->sent = SCTP_DATAGRAM_RESEND;
1167 				chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
1168 				sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
1169 			}
1170 			chk->whoTo = alt;
1171 			atomic_add_int(&alt->ref_count, 1);
1172 		}
1173 	}
1174 	if (!(net->dest_state & SCTP_ADDR_REACHABLE)) {
1175 		/*
1176 		 * If the address went un-reachable, we need to move to
1177 		 * alternates for ALL chk's in queue
1178 		 */
1179 		sctp_move_chunks_from_net(stcb, net);
1180 	}
1181 	sctp_free_remote_addr(net);
1182 
1183 	/* mark the retran info */
1184 	if (strrst->sent != SCTP_DATAGRAM_RESEND)
1185 		sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
1186 	strrst->sent = SCTP_DATAGRAM_RESEND;
1187 	strrst->flags |= CHUNK_FLAGS_FRAGMENT_OK;
1188 
1189 	/* restart the timer */
1190 	sctp_timer_start(SCTP_TIMER_TYPE_STRRESET, inp, stcb, alt);
1191 	return (0);
1192 }
1193 
1194 int
1195 sctp_asconf_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb,
1196 		  struct sctp_nets *net)
1197 {
1198 	struct sctp_nets *alt;
1199 	struct sctp_tmit_chunk *asconf, *chk;
1200 
1201 	/* is this a first send, or a retransmission? */
1202 	if (TAILQ_EMPTY(&stcb->asoc.asconf_send_queue)) {
1203 		/* compose a new ASCONF chunk and send it */
1204 		sctp_send_asconf(stcb, net, SCTP_ADDR_NOT_LOCKED);
1205 	} else {
1206 		/*
1207 		 * Retransmission of the existing ASCONF is needed
1208 		 */
1209 
1210 		/* find the existing ASCONF */
1211 		asconf = TAILQ_FIRST(&stcb->asoc.asconf_send_queue);
1212 		if (asconf == NULL) {
1213 			return (0);
1214 		}
1215 		net = asconf->whoTo;
1216 		/* do threshold management */
1217 		if (sctp_threshold_management(inp, stcb, net,
1218 		    stcb->asoc.max_send_times)) {
1219 			/* Assoc is over */
1220 			return (1);
1221 		}
1222 		if (asconf->snd_count > stcb->asoc.max_send_times) {
1223 			/*
1224 			 * Something is rotten: our peer is not responding to
1225 			 * ASCONFs but apparently is to other chunks.  i.e. it
1226 			 * is not properly handling the chunk type upper bits.
1227 			 * Mark this peer as ASCONF incapable and cleanup.
1228 			 */
1229 			SCTPDBG(SCTP_DEBUG_TIMER1, "asconf_timer: Peer has not responded to our repeated ASCONFs\n");
1230 			sctp_asconf_cleanup(stcb);
1231 			return (0);
1232 		}
1233 		/*
1234 		 * cleared threshold management, so now backoff the net and
1235 		 * select an alternate
1236 		 */
1237 		sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
1238 		alt = sctp_find_alternate_net(stcb, net, 0);
1239 		if (asconf->whoTo != alt) {
1240 			asconf->whoTo = alt;
1241 			atomic_add_int(&alt->ref_count, 1);
1242 		}
1243 
1244 		/* See if an ECN Echo is also stranded */
1245 		TAILQ_FOREACH(chk, &stcb->asoc.control_send_queue, sctp_next) {
1246 			if ((chk->whoTo == net) &&
1247 			    (chk->rec.chunk_id.id == SCTP_ECN_ECHO)) {
1248 				sctp_free_remote_addr(chk->whoTo);
1249 				chk->whoTo = alt;
1250 				if (chk->sent != SCTP_DATAGRAM_RESEND) {
1251 					chk->sent = SCTP_DATAGRAM_RESEND;
1252 					chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
1253 					sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
1254 				}
1255 				atomic_add_int(&alt->ref_count, 1);
1256 			}
1257 		}
1258 		TAILQ_FOREACH(chk, &stcb->asoc.asconf_send_queue, sctp_next) {
1259 			if (chk->whoTo != alt) {
1260 				sctp_free_remote_addr(chk->whoTo);
1261 				chk->whoTo = alt;
1262 				atomic_add_int(&alt->ref_count, 1);
1263 			}
1264 			if (asconf->sent != SCTP_DATAGRAM_RESEND && chk->sent != SCTP_DATAGRAM_UNSENT)
1265 				sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
1266 			chk->sent = SCTP_DATAGRAM_RESEND;
1267 			chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
1268 		}
1269 		if (!(net->dest_state & SCTP_ADDR_REACHABLE)) {
1270 			/*
1271 			 * If the address went un-reachable, we need to move
1272 			 * to the alternate for ALL chunks in queue
1273 			 */
1274 			sctp_move_chunks_from_net(stcb, net);
1275 		}
1276 		sctp_free_remote_addr(net);
1277 
1278 		/* mark the retran info */
1279 		if (asconf->sent != SCTP_DATAGRAM_RESEND)
1280 			sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
1281 		asconf->sent = SCTP_DATAGRAM_RESEND;
1282 		asconf->flags |= CHUNK_FLAGS_FRAGMENT_OK;
1283 
1284 		/* send another ASCONF if any and we can do */
1285 		sctp_send_asconf(stcb, alt, SCTP_ADDR_NOT_LOCKED);
1286 	}
1287 	return (0);
1288 }
1289 
1290 /* Mobility adaptation */
1291 void
1292 sctp_delete_prim_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
1293 {
1294 	if (stcb->asoc.deleted_primary == NULL) {
1295 		SCTPDBG(SCTP_DEBUG_ASCONF1, "delete_prim_timer: deleted_primary is not stored...\n");
1296 		sctp_mobility_feature_off(inp, SCTP_MOBILITY_PRIM_DELETED);
1297 		return;
1298 	}
1299 	SCTPDBG(SCTP_DEBUG_ASCONF1, "delete_prim_timer: finished to keep deleted primary ");
1300 	SCTPDBG_ADDR(SCTP_DEBUG_ASCONF1, &stcb->asoc.deleted_primary->ro._l_addr.sa);
1301 	sctp_free_remote_addr(stcb->asoc.deleted_primary);
1302 	stcb->asoc.deleted_primary = NULL;
1303 	sctp_mobility_feature_off(inp, SCTP_MOBILITY_PRIM_DELETED);
1304 	return;
1305 }
1306 
1307 /*
1308  * For the shutdown and shutdown-ack, we do not keep one around on the
1309  * control queue. This means we must generate a new one and call the general
1310  * chunk output routine, AFTER having done threshold management.
1311  * It is assumed that net is non-NULL.
1312  */
1313 int
1314 sctp_shutdown_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb,
1315     struct sctp_nets *net)
1316 {
1317 	struct sctp_nets *alt;
1318 
1319 	/* first threshold management */
1320 	if (sctp_threshold_management(inp, stcb, net, stcb->asoc.max_send_times)) {
1321 		/* Assoc is over */
1322 		return (1);
1323 	}
1324 	sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
1325 	/* second select an alternative */
1326 	alt = sctp_find_alternate_net(stcb, net, 0);
1327 
1328 	/* third generate a shutdown into the queue for out net */
1329 	sctp_send_shutdown(stcb, alt);
1330 
1331 	/* fourth restart timer */
1332 	sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWN, inp, stcb, alt);
1333 	return (0);
1334 }
1335 
1336 int
1337 sctp_shutdownack_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb,
1338     struct sctp_nets *net)
1339 {
1340 	struct sctp_nets *alt;
1341 
1342 	/* first threshold management */
1343 	if (sctp_threshold_management(inp, stcb, net, stcb->asoc.max_send_times)) {
1344 		/* Assoc is over */
1345 		return (1);
1346 	}
1347 	sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
1348 	/* second select an alternative */
1349 	alt = sctp_find_alternate_net(stcb, net, 0);
1350 
1351 	/* third generate a shutdown into the queue for out net */
1352 	sctp_send_shutdown_ack(stcb, alt);
1353 
1354 	/* fourth restart timer */
1355 	sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNACK, inp, stcb, alt);
1356 	return (0);
1357 }
1358 
1359 static void
1360 sctp_audit_stream_queues_for_size(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
1361 {
1362 	struct sctp_stream_queue_pending *sp;
1363 	unsigned int i, chks_in_queue = 0;
1364 	int being_filled = 0;
1365 
1366 	KASSERT(inp != NULL, ("inp is NULL"));
1367 	KASSERT(stcb != NULL, ("stcb is NULL"));
1368 
1369 	SCTP_TCB_SEND_LOCK(stcb);
1370 	KASSERT(TAILQ_EMPTY(&stcb->asoc.send_queue), ("send_queue not empty"));
1371 	KASSERT(TAILQ_EMPTY(&stcb->asoc.sent_queue), ("sent_queue not empty"));
1372 
1373 	if (stcb->asoc.sent_queue_retran_cnt) {
1374 		SCTP_PRINTF("Hmm, sent_queue_retran_cnt is non-zero %d\n",
1375 			    stcb->asoc.sent_queue_retran_cnt);
1376 		stcb->asoc.sent_queue_retran_cnt = 0;
1377 	}
1378 	if (stcb->asoc.ss_functions.sctp_ss_is_empty(stcb, &stcb->asoc)) {
1379 		/* No stream scheduler information, initialize scheduler */
1380 		stcb->asoc.ss_functions.sctp_ss_init(stcb, &stcb->asoc);
1381 		if (!stcb->asoc.ss_functions.sctp_ss_is_empty(stcb, &stcb->asoc)) {
1382 			/* yep, we lost a stream or two */
1383 			SCTP_PRINTF("Found additional streams NOT managed by scheduler, corrected\n");
1384 		} else {
1385 			/* no streams lost */
1386 			stcb->asoc.total_output_queue_size = 0;
1387 		}
1388 	}
1389 	/* Check to see if some data queued, if so report it */
1390 	for (i = 0; i < stcb->asoc.streamoutcnt; i++) {
1391 		if (!TAILQ_EMPTY(&stcb->asoc.strmout[i].outqueue)) {
1392 			TAILQ_FOREACH(sp, &stcb->asoc.strmout[i].outqueue, next) {
1393 				if (sp->msg_is_complete)
1394 					being_filled++;
1395 				chks_in_queue++;
1396 			}
1397 		}
1398 	}
1399 	if (chks_in_queue != stcb->asoc.stream_queue_cnt) {
1400 		SCTP_PRINTF("Hmm, stream queue cnt at %d I counted %d in stream out wheel\n",
1401 			    stcb->asoc.stream_queue_cnt, chks_in_queue);
1402 	}
1403 	SCTP_TCB_SEND_UNLOCK(stcb);
1404 	if (chks_in_queue) {
1405 		/* call the output queue function */
1406 		sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_T3, SCTP_SO_NOT_LOCKED);
1407 		if ((TAILQ_EMPTY(&stcb->asoc.send_queue)) &&
1408 		    (TAILQ_EMPTY(&stcb->asoc.sent_queue))) {
1409 			/*
1410 			 * Probably should go in and make it go back through
1411 			 * and add fragments allowed
1412 			 */
1413 			if (being_filled == 0) {
1414 				SCTP_PRINTF("Still nothing moved %d chunks are stuck\n",
1415 					    chks_in_queue);
1416 			}
1417 		}
1418 	} else {
1419 		SCTP_PRINTF("Found no chunks on any queue tot:%lu\n",
1420 			    (u_long)stcb->asoc.total_output_queue_size);
1421 		stcb->asoc.total_output_queue_size = 0;
1422 	}
1423 }
1424 
1425 int
1426 sctp_heartbeat_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb,
1427     struct sctp_nets *net)
1428 {
1429 	uint8_t net_was_pf;
1430 
1431 	if (net->dest_state & SCTP_ADDR_PF) {
1432 		net_was_pf = 1;
1433 	} else {
1434 		net_was_pf = 0;
1435 	}
1436 	if (net->hb_responded == 0) {
1437 		if (net->ro._s_addr) {
1438 			/* Invalidate the src address if we did not get
1439 			 * a response last time.
1440 			 */
1441 			sctp_free_ifa(net->ro._s_addr);
1442 			net->ro._s_addr = NULL;
1443 			net->src_addr_selected = 0;
1444 		}
1445 		sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
1446 		if (sctp_threshold_management(inp, stcb, net, stcb->asoc.max_send_times)) {
1447 			/* Assoc is over */
1448 			return (1);
1449 		}
1450 	}
1451 	/* Zero PBA, if it needs it */
1452 	if (net->partial_bytes_acked) {
1453 		net->partial_bytes_acked = 0;
1454 	}
1455 	if ((stcb->asoc.total_output_queue_size > 0) &&
1456 	    (TAILQ_EMPTY(&stcb->asoc.send_queue)) &&
1457 	    (TAILQ_EMPTY(&stcb->asoc.sent_queue))) {
1458 		sctp_audit_stream_queues_for_size(inp, stcb);
1459 	}
1460 	if (!(net->dest_state & SCTP_ADDR_NOHB) &&
1461 	    !((net_was_pf == 0) && (net->dest_state & SCTP_ADDR_PF))) {
1462 		/* when move to PF during threshold mangement, a HB has been
1463 		   queued in that routine */
1464 		uint32_t ms_gone_by;
1465 
1466 		if ((net->last_sent_time.tv_sec > 0) ||
1467 		    (net->last_sent_time.tv_usec > 0)) {
1468 #if defined(__FreeBSD__) && !defined(__Userspace__)
1469 			struct timeval diff;
1470 
1471 			SCTP_GETTIME_TIMEVAL(&diff);
1472 			timevalsub(&diff, &net->last_sent_time);
1473 #else
1474 			struct timeval diff, now;
1475 
1476 			SCTP_GETTIME_TIMEVAL(&now);
1477 			timersub(&now, &net->last_sent_time, &diff);
1478 #endif
1479 			ms_gone_by = (uint32_t)(diff.tv_sec * 1000) +
1480 			             (uint32_t)(diff.tv_usec / 1000);
1481 		} else {
1482 			ms_gone_by = 0xffffffff;
1483 		}
1484 		if ((ms_gone_by >= net->heart_beat_delay) ||
1485 		    (net->dest_state & SCTP_ADDR_PF)) {
1486 			sctp_send_hb(stcb, net, SCTP_SO_NOT_LOCKED);
1487 		}
1488 	}
1489 	return (0);
1490 }
1491 
1492 void
1493 sctp_pathmtu_timer(struct sctp_inpcb *inp,
1494     struct sctp_tcb *stcb,
1495     struct sctp_nets *net)
1496 {
1497 	uint32_t next_mtu, mtu;
1498 
1499 	next_mtu = sctp_get_next_mtu(net->mtu);
1500 
1501 	if ((next_mtu > net->mtu) && (net->port == 0)) {
1502 		if ((net->src_addr_selected == 0) ||
1503 		    (net->ro._s_addr == NULL) ||
1504 		    (net->ro._s_addr->localifa_flags & SCTP_BEING_DELETED)) {
1505 			if ((net->ro._s_addr != NULL) && (net->ro._s_addr->localifa_flags & SCTP_BEING_DELETED)) {
1506 				sctp_free_ifa(net->ro._s_addr);
1507 				net->ro._s_addr = NULL;
1508 				net->src_addr_selected = 0;
1509 			} else  if (net->ro._s_addr == NULL) {
1510 #if defined(INET6) && defined(SCTP_EMBEDDED_V6_SCOPE)
1511 				if (net->ro._l_addr.sa.sa_family == AF_INET6) {
1512 					struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&net->ro._l_addr;
1513 					/* KAME hack: embed scopeid */
1514 #if defined(__APPLE__) && !defined(__Userspace__)
1515 #if defined(APPLE_LEOPARD) || defined(APPLE_SNOWLEOPARD)
1516 					(void)in6_embedscope(&sin6->sin6_addr, sin6, NULL, NULL);
1517 #else
1518 					(void)in6_embedscope(&sin6->sin6_addr, sin6, NULL, NULL, NULL);
1519 #endif
1520 #elif defined(SCTP_KAME)
1521 					(void)sa6_embedscope(sin6, MODULE_GLOBAL(ip6_use_defzone));
1522 #else
1523 					(void)in6_embedscope(&sin6->sin6_addr, sin6);
1524 #endif
1525 				}
1526 #endif
1527 
1528 				net->ro._s_addr = sctp_source_address_selection(inp,
1529 										stcb,
1530 										(sctp_route_t *)&net->ro,
1531 										net, 0, stcb->asoc.vrf_id);
1532 #if defined(INET6) && defined(SCTP_EMBEDDED_V6_SCOPE)
1533 				if (net->ro._l_addr.sa.sa_family == AF_INET6) {
1534 					struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&net->ro._l_addr;
1535 #ifdef SCTP_KAME
1536 					(void)sa6_recoverscope(sin6);
1537 #else
1538 					(void)in6_recoverscope(sin6, &sin6->sin6_addr, NULL);
1539 #endif	/* SCTP_KAME */
1540 				}
1541 #endif	/* INET6 */
1542 			}
1543 			if (net->ro._s_addr)
1544 				net->src_addr_selected = 1;
1545 		}
1546 		if (net->ro._s_addr) {
1547 #if defined(__FreeBSD__) && !defined(__Userspace__)
1548 			mtu = SCTP_GATHER_MTU_FROM_ROUTE(net->ro._s_addr, &net->ro._s_addr.sa, net->ro.ro_nh);
1549 #else
1550 			mtu = SCTP_GATHER_MTU_FROM_ROUTE(net->ro._s_addr, &net->ro._s_addr.sa, net->ro.ro_rt);
1551 #endif
1552 #if defined(INET) || defined(INET6)
1553 			if (net->port) {
1554 				mtu -= sizeof(struct udphdr);
1555 			}
1556 #endif
1557 			if (mtu > next_mtu) {
1558 				net->mtu = next_mtu;
1559 			} else {
1560 				net->mtu = mtu;
1561 			}
1562 		}
1563 	}
1564 	/* restart the timer */
1565 	sctp_timer_start(SCTP_TIMER_TYPE_PATHMTURAISE, inp, stcb, net);
1566 }
1567 
1568 void
1569 sctp_autoclose_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
1570 {
1571 	struct timeval tn, *tim_touse;
1572 	struct sctp_association *asoc;
1573 	uint32_t ticks_gone_by;
1574 
1575 	(void)SCTP_GETTIME_TIMEVAL(&tn);
1576 	if (stcb->asoc.sctp_autoclose_ticks > 0 &&
1577 	    sctp_is_feature_on(inp, SCTP_PCB_FLAGS_AUTOCLOSE)) {
1578 		/* Auto close is on */
1579 		asoc = &stcb->asoc;
1580 		/* pick the time to use */
1581 		if (asoc->time_last_rcvd.tv_sec >
1582 		    asoc->time_last_sent.tv_sec) {
1583 			tim_touse = &asoc->time_last_rcvd;
1584 		} else {
1585 			tim_touse = &asoc->time_last_sent;
1586 		}
1587 		/* Now has long enough transpired to autoclose? */
1588 		ticks_gone_by = sctp_secs_to_ticks((uint32_t)(tn.tv_sec - tim_touse->tv_sec));
1589 		if (ticks_gone_by >= asoc->sctp_autoclose_ticks) {
1590 			/*
1591 			 * autoclose time has hit, call the output routine,
1592 			 * which should do nothing just to be SURE we don't
1593 			 * have hanging data. We can then safely check the
1594 			 * queues and know that we are clear to send
1595 			 * shutdown
1596 			 */
1597 			sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_AUTOCLOSE_TMR, SCTP_SO_NOT_LOCKED);
1598 			/* Are we clean? */
1599 			if (TAILQ_EMPTY(&asoc->send_queue) &&
1600 			    TAILQ_EMPTY(&asoc->sent_queue)) {
1601 				/*
1602 				 * there is nothing queued to send, so I'm
1603 				 * done...
1604 				 */
1605 				if (SCTP_GET_STATE(stcb) != SCTP_STATE_SHUTDOWN_SENT) {
1606 					/* only send SHUTDOWN 1st time thru */
1607 					struct sctp_nets *net;
1608 
1609 					if ((SCTP_GET_STATE(stcb) == SCTP_STATE_OPEN) ||
1610 					    (SCTP_GET_STATE(stcb) == SCTP_STATE_SHUTDOWN_RECEIVED)) {
1611 						SCTP_STAT_DECR_GAUGE32(sctps_currestab);
1612 					}
1613 					SCTP_SET_STATE(stcb, SCTP_STATE_SHUTDOWN_SENT);
1614 					sctp_stop_timers_for_shutdown(stcb);
1615 					if (stcb->asoc.alternate) {
1616 						net = stcb->asoc.alternate;
1617 					} else {
1618 						net = stcb->asoc.primary_destination;
1619 					}
1620 					sctp_send_shutdown(stcb, net);
1621 					sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWN,
1622 							 stcb->sctp_ep, stcb, net);
1623 					sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
1624 							 stcb->sctp_ep, stcb, NULL);
1625 				}
1626 			}
1627 		} else {
1628 			/*
1629 			 * No auto close at this time, reset t-o to check
1630 			 * later
1631 			 */
1632 			uint32_t tmp;
1633 
1634 			/* fool the timer startup to use the time left */
1635 			tmp = asoc->sctp_autoclose_ticks;
1636 			asoc->sctp_autoclose_ticks -= ticks_gone_by;
1637 			sctp_timer_start(SCTP_TIMER_TYPE_AUTOCLOSE, inp, stcb, NULL);
1638 			/* restore the real tick value */
1639 			asoc->sctp_autoclose_ticks = tmp;
1640 		}
1641 	}
1642 }
1643 
1644