xref: /freebsd/sys/netinet/sctp_timer.c (revision fdafd315ad0d0f28a11b9fb4476a9ab059c62b92)
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 #define _IP_VHL
36 #include <netinet/sctp_os.h>
37 #include <netinet/sctp_pcb.h>
38 
39 #include <netinet/sctp_var.h>
40 #include <netinet/sctp_sysctl.h>
41 #include <netinet/sctp_timer.h>
42 #include <netinet/sctputil.h>
43 #include <netinet/sctp_output.h>
44 #include <netinet/sctp_header.h>
45 #include <netinet/sctp_indata.h>
46 #include <netinet/sctp_asconf.h>
47 #include <netinet/sctp_input.h>
48 #include <netinet/sctp.h>
49 #include <netinet/sctp_uio.h>
50 #if defined(INET) || defined(INET6)
51 #include <netinet/udp.h>
52 #endif
53 
54 void
sctp_audit_retranmission_queue(struct sctp_association * asoc)55 sctp_audit_retranmission_queue(struct sctp_association *asoc)
56 {
57 	struct sctp_tmit_chunk *chk;
58 
59 	SCTPDBG(SCTP_DEBUG_TIMER4, "Audit invoked on send queue cnt:%d onqueue:%d\n",
60 	    asoc->sent_queue_retran_cnt,
61 	    asoc->sent_queue_cnt);
62 	asoc->sent_queue_retran_cnt = 0;
63 	asoc->sent_queue_cnt = 0;
64 	TAILQ_FOREACH(chk, &asoc->sent_queue, sctp_next) {
65 		if (chk->sent == SCTP_DATAGRAM_RESEND) {
66 			sctp_ucount_incr(asoc->sent_queue_retran_cnt);
67 		}
68 		asoc->sent_queue_cnt++;
69 	}
70 	TAILQ_FOREACH(chk, &asoc->control_send_queue, sctp_next) {
71 		if (chk->sent == SCTP_DATAGRAM_RESEND) {
72 			sctp_ucount_incr(asoc->sent_queue_retran_cnt);
73 		}
74 	}
75 	TAILQ_FOREACH(chk, &asoc->asconf_send_queue, sctp_next) {
76 		if (chk->sent == SCTP_DATAGRAM_RESEND) {
77 			sctp_ucount_incr(asoc->sent_queue_retran_cnt);
78 		}
79 	}
80 	SCTPDBG(SCTP_DEBUG_TIMER4, "Audit completes retran:%d onqueue:%d\n",
81 	    asoc->sent_queue_retran_cnt,
82 	    asoc->sent_queue_cnt);
83 }
84 
85 static int
sctp_threshold_management(struct sctp_inpcb * inp,struct sctp_tcb * stcb,struct sctp_nets * net,uint16_t threshold)86 sctp_threshold_management(struct sctp_inpcb *inp, struct sctp_tcb *stcb,
87     struct sctp_nets *net, uint16_t threshold)
88 {
89 	KASSERT(stcb != NULL, ("stcb is NULL"));
90 	SCTP_TCB_LOCK_ASSERT(stcb);
91 
92 	if (net != NULL) {
93 		net->error_count++;
94 		SCTPDBG(SCTP_DEBUG_TIMER4, "Error count for %p now %d thresh:%d\n",
95 		    (void *)net, net->error_count,
96 		    net->failure_threshold);
97 		if (net->error_count > net->failure_threshold) {
98 			/* We had a threshold failure */
99 			if (net->dest_state & SCTP_ADDR_REACHABLE) {
100 				net->dest_state &= ~SCTP_ADDR_REACHABLE;
101 				net->dest_state &= ~SCTP_ADDR_REQ_PRIMARY;
102 				net->dest_state &= ~SCTP_ADDR_PF;
103 				sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_DOWN,
104 				    stcb, 0,
105 				    (void *)net, SCTP_SO_NOT_LOCKED);
106 			}
107 		} else if ((net->pf_threshold < net->failure_threshold) &&
108 		    (net->error_count > net->pf_threshold)) {
109 			if ((net->dest_state & SCTP_ADDR_PF) == 0) {
110 				net->dest_state |= SCTP_ADDR_PF;
111 				net->last_active = sctp_get_tick_count();
112 				sctp_send_hb(stcb, net, SCTP_SO_NOT_LOCKED);
113 				sctp_timer_stop(SCTP_TIMER_TYPE_HEARTBEAT,
114 				    inp, stcb, net,
115 				    SCTP_FROM_SCTP_TIMER + SCTP_LOC_1);
116 				sctp_timer_start(SCTP_TIMER_TYPE_HEARTBEAT, inp, stcb, net);
117 			}
118 		}
119 		if ((net->dest_state & SCTP_ADDR_UNCONFIRMED) == 0) {
120 			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
121 				sctp_misc_ints(SCTP_THRESHOLD_INCR,
122 				    stcb->asoc.overall_error_count,
123 				    (stcb->asoc.overall_error_count + 1),
124 				    SCTP_FROM_SCTP_TIMER,
125 				    __LINE__);
126 			}
127 			stcb->asoc.overall_error_count++;
128 		}
129 	} else {
130 		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
131 			sctp_misc_ints(SCTP_THRESHOLD_INCR,
132 			    stcb->asoc.overall_error_count,
133 			    (stcb->asoc.overall_error_count + 1),
134 			    SCTP_FROM_SCTP_TIMER,
135 			    __LINE__);
136 		}
137 		stcb->asoc.overall_error_count++;
138 	}
139 	SCTPDBG(SCTP_DEBUG_TIMER4, "Overall error count for %p now %d thresh:%u state:%x\n",
140 	    (void *)&stcb->asoc, stcb->asoc.overall_error_count,
141 	    (uint32_t)threshold,
142 	    ((net == NULL) ? (uint32_t)0 : (uint32_t)net->dest_state));
143 	/*
144 	 * We specifically do not do >= to give the assoc one more change
145 	 * before we fail it.
146 	 */
147 	if (stcb->asoc.overall_error_count > threshold) {
148 		/* Abort notification sends a ULP notify */
149 		struct mbuf *op_err;
150 
151 		op_err = sctp_generate_cause(SCTP_BASE_SYSCTL(sctp_diag_info_code),
152 		    "Association error counter exceeded");
153 		inp->last_abort_code = SCTP_FROM_SCTP_TIMER + SCTP_LOC_2;
154 		sctp_abort_an_association(inp, stcb, op_err, true, SCTP_SO_NOT_LOCKED);
155 		return (1);
156 	}
157 	return (0);
158 }
159 
160 /*
161  * sctp_find_alternate_net() returns a non-NULL pointer as long as there
162  * exists nets, which are not being deleted.
163  */
164 struct sctp_nets *
sctp_find_alternate_net(struct sctp_tcb * stcb,struct sctp_nets * net,int mode)165 sctp_find_alternate_net(struct sctp_tcb *stcb,
166     struct sctp_nets *net,
167     int mode)
168 {
169 	/* Find and return an alternate network if possible */
170 	struct sctp_nets *alt, *mnet, *min_errors_net = NULL, *max_cwnd_net = NULL;
171 	bool looped;
172 
173 	/* JRS 5/14/07 - Initialize min_errors to an impossible value. */
174 	int min_errors = -1;
175 	uint32_t max_cwnd = 0;
176 
177 	if (stcb->asoc.numnets == 1) {
178 		/* No selection can be made. */
179 		return (TAILQ_FIRST(&stcb->asoc.nets));
180 	}
181 	/*
182 	 * JRS 5/14/07 - If mode is set to 2, use the CMT PF find alternate
183 	 * net algorithm. This algorithm chooses the active destination (not
184 	 * in PF state) with the largest cwnd value. If all destinations are
185 	 * in PF state, unreachable, or unconfirmed, choose the destination
186 	 * that is in PF state with the lowest error count. In case of a
187 	 * tie, choose the destination that was most recently active.
188 	 */
189 	if (mode == 2) {
190 		TAILQ_FOREACH(mnet, &stcb->asoc.nets, sctp_next) {
191 			/*
192 			 * JRS 5/14/07 - If the destination is unreachable
193 			 * or unconfirmed, skip it.
194 			 */
195 			if (((mnet->dest_state & SCTP_ADDR_REACHABLE) != SCTP_ADDR_REACHABLE) ||
196 			    (mnet->dest_state & SCTP_ADDR_UNCONFIRMED)) {
197 				continue;
198 			}
199 			/*
200 			 * JRS 5/14/07 -  If the destination is reachable
201 			 * but in PF state, compare the error count of the
202 			 * destination to the minimum error count seen thus
203 			 * far. Store the destination with the lower error
204 			 * count.  If the error counts are equal, store the
205 			 * destination that was most recently active.
206 			 */
207 			if (mnet->dest_state & SCTP_ADDR_PF) {
208 				/*
209 				 * JRS 5/14/07 - If the destination under
210 				 * consideration is the current destination,
211 				 * work as if the error count is one higher.
212 				 * The actual error count will not be
213 				 * incremented until later in the t3
214 				 * handler.
215 				 */
216 				if (mnet == net) {
217 					if (min_errors == -1) {
218 						min_errors = mnet->error_count + 1;
219 						min_errors_net = mnet;
220 					} else if (mnet->error_count + 1 < min_errors) {
221 						min_errors = mnet->error_count + 1;
222 						min_errors_net = mnet;
223 					} else if (mnet->error_count + 1 == min_errors
224 					    && mnet->last_active > min_errors_net->last_active) {
225 						min_errors_net = mnet;
226 						min_errors = mnet->error_count + 1;
227 					}
228 					continue;
229 				} else {
230 					if (min_errors == -1) {
231 						min_errors = mnet->error_count;
232 						min_errors_net = mnet;
233 					} else if (mnet->error_count < min_errors) {
234 						min_errors = mnet->error_count;
235 						min_errors_net = mnet;
236 					} else if (mnet->error_count == min_errors
237 					    && mnet->last_active > min_errors_net->last_active) {
238 						min_errors_net = mnet;
239 						min_errors = mnet->error_count;
240 					}
241 					continue;
242 				}
243 			}
244 			/*
245 			 * JRS 5/14/07 - If the destination is reachable and
246 			 * not in PF state, compare the cwnd of the
247 			 * destination to the highest cwnd seen thus far.
248 			 * Store the destination with the higher cwnd value.
249 			 * If the cwnd values are equal, randomly choose one
250 			 * of the two destinations.
251 			 */
252 			if (max_cwnd < mnet->cwnd) {
253 				max_cwnd_net = mnet;
254 				max_cwnd = mnet->cwnd;
255 			} else if (max_cwnd == mnet->cwnd) {
256 				uint32_t rndval;
257 				uint8_t this_random;
258 
259 				if (stcb->asoc.hb_random_idx > 3) {
260 					rndval = sctp_select_initial_TSN(&stcb->sctp_ep->sctp_ep);
261 					memcpy(stcb->asoc.hb_random_values, &rndval, sizeof(stcb->asoc.hb_random_values));
262 					this_random = stcb->asoc.hb_random_values[0];
263 					stcb->asoc.hb_random_idx++;
264 					stcb->asoc.hb_ect_randombit = 0;
265 				} else {
266 					this_random = stcb->asoc.hb_random_values[stcb->asoc.hb_random_idx];
267 					stcb->asoc.hb_random_idx++;
268 					stcb->asoc.hb_ect_randombit = 0;
269 				}
270 				if (this_random % 2 == 1) {
271 					max_cwnd_net = mnet;
272 					max_cwnd = mnet->cwnd;	/* Useless? */
273 				}
274 			}
275 		}
276 		if (max_cwnd_net == NULL) {
277 			if (min_errors_net == NULL) {
278 				return (net);
279 			}
280 			return (min_errors_net);
281 		} else {
282 			return (max_cwnd_net);
283 		}
284 	}			/* JRS 5/14/07 - If mode is set to 1, use the
285 				 * CMT policy for choosing an alternate net. */
286 	else if (mode == 1) {
287 		TAILQ_FOREACH(mnet, &stcb->asoc.nets, sctp_next) {
288 			if (((mnet->dest_state & SCTP_ADDR_REACHABLE) != SCTP_ADDR_REACHABLE) ||
289 			    (mnet->dest_state & SCTP_ADDR_UNCONFIRMED)) {
290 				/*
291 				 * will skip ones that are not-reachable or
292 				 * unconfirmed
293 				 */
294 				continue;
295 			}
296 			if (max_cwnd < mnet->cwnd) {
297 				max_cwnd_net = mnet;
298 				max_cwnd = mnet->cwnd;
299 			} else if (max_cwnd == mnet->cwnd) {
300 				uint32_t rndval;
301 				uint8_t this_random;
302 
303 				if (stcb->asoc.hb_random_idx > 3) {
304 					rndval = sctp_select_initial_TSN(&stcb->sctp_ep->sctp_ep);
305 					memcpy(stcb->asoc.hb_random_values, &rndval,
306 					    sizeof(stcb->asoc.hb_random_values));
307 					this_random = stcb->asoc.hb_random_values[0];
308 					stcb->asoc.hb_random_idx = 0;
309 					stcb->asoc.hb_ect_randombit = 0;
310 				} else {
311 					this_random = stcb->asoc.hb_random_values[stcb->asoc.hb_random_idx];
312 					stcb->asoc.hb_random_idx++;
313 					stcb->asoc.hb_ect_randombit = 0;
314 				}
315 				if (this_random % 2) {
316 					max_cwnd_net = mnet;
317 					max_cwnd = mnet->cwnd;
318 				}
319 			}
320 		}
321 		if (max_cwnd_net) {
322 			return (max_cwnd_net);
323 		}
324 	}
325 	/* Look for an alternate net, which is active. */
326 	if ((net != NULL) && ((net->dest_state & SCTP_ADDR_BEING_DELETED) == 0)) {
327 		alt = TAILQ_NEXT(net, sctp_next);
328 	} else {
329 		alt = TAILQ_FIRST(&stcb->asoc.nets);
330 	}
331 	looped = false;
332 	for (;;) {
333 		if (alt == NULL) {
334 			if (!looped) {
335 				alt = TAILQ_FIRST(&stcb->asoc.nets);
336 				looped = true;
337 			}
338 			/* Definitely out of candidates. */
339 			if (alt == NULL) {
340 				break;
341 			}
342 		}
343 		if (alt->ro.ro_nh == NULL) {
344 			if (alt->ro._s_addr) {
345 				sctp_free_ifa(alt->ro._s_addr);
346 				alt->ro._s_addr = NULL;
347 			}
348 			alt->src_addr_selected = 0;
349 		}
350 		if (((alt->dest_state & SCTP_ADDR_REACHABLE) == SCTP_ADDR_REACHABLE) &&
351 		    (alt->ro.ro_nh != NULL) &&
352 		    ((alt->dest_state & SCTP_ADDR_UNCONFIRMED) == 0) &&
353 		    (alt != net)) {
354 			/* Found an alternate net, which is reachable. */
355 			break;
356 		}
357 		alt = TAILQ_NEXT(alt, sctp_next);
358 	}
359 
360 	if (alt == NULL) {
361 		/*
362 		 * In case no active alternate net has been found, look for
363 		 * an alternate net, which is confirmed.
364 		 */
365 		if ((net != NULL) && ((net->dest_state & SCTP_ADDR_BEING_DELETED) == 0)) {
366 			alt = TAILQ_NEXT(net, sctp_next);
367 		} else {
368 			alt = TAILQ_FIRST(&stcb->asoc.nets);
369 		}
370 		looped = false;
371 		for (;;) {
372 			if (alt == NULL) {
373 				if (!looped) {
374 					alt = TAILQ_FIRST(&stcb->asoc.nets);
375 					looped = true;
376 				}
377 				/* Definitely out of candidates. */
378 				if (alt == NULL) {
379 					break;
380 				}
381 			}
382 			if (((alt->dest_state & SCTP_ADDR_UNCONFIRMED) == 0) &&
383 			    (alt != net)) {
384 				/*
385 				 * Found an alternate net, which is
386 				 * confirmed.
387 				 */
388 				break;
389 			}
390 			alt = TAILQ_NEXT(alt, sctp_next);
391 		}
392 	}
393 	if (alt == NULL) {
394 		/*
395 		 * In case no confirmed alternate net has been found, just
396 		 * return net, if it is not being deleted. In the other case
397 		 * just return the first net.
398 		 */
399 		if ((net != NULL) && ((net->dest_state & SCTP_ADDR_BEING_DELETED) == 0)) {
400 			alt = net;
401 		}
402 		if (alt == NULL) {
403 			alt = TAILQ_FIRST(&stcb->asoc.nets);
404 		}
405 	}
406 	return (alt);
407 }
408 
409 static void
sctp_backoff_on_timeout(struct sctp_tcb * stcb,struct sctp_nets * net,int win_probe,int num_marked,int num_abandoned)410 sctp_backoff_on_timeout(struct sctp_tcb *stcb,
411     struct sctp_nets *net,
412     int win_probe,
413     int num_marked, int num_abandoned)
414 {
415 	if (net->RTO == 0) {
416 		if (net->RTO_measured) {
417 			net->RTO = stcb->asoc.minrto;
418 		} else {
419 			net->RTO = stcb->asoc.initial_rto;
420 		}
421 	}
422 	net->RTO <<= 1;
423 	if (net->RTO > stcb->asoc.maxrto) {
424 		net->RTO = stcb->asoc.maxrto;
425 	}
426 	if ((win_probe == 0) && (num_marked || num_abandoned)) {
427 		/* We don't apply penalty to window probe scenarios */
428 		/* JRS - Use the congestion control given in the CC module */
429 		stcb->asoc.cc_functions.sctp_cwnd_update_after_timeout(stcb, net);
430 	}
431 }
432 
433 #ifndef INVARIANTS
434 static void
sctp_recover_sent_list(struct sctp_tcb * stcb)435 sctp_recover_sent_list(struct sctp_tcb *stcb)
436 {
437 	struct sctp_tmit_chunk *chk, *nchk;
438 	struct sctp_association *asoc;
439 
440 	asoc = &stcb->asoc;
441 	TAILQ_FOREACH_SAFE(chk, &asoc->sent_queue, sctp_next, nchk) {
442 		if (SCTP_TSN_GE(asoc->last_acked_seq, chk->rec.data.tsn)) {
443 			SCTP_PRINTF("Found chk:%p tsn:%x <= last_acked_seq:%x\n",
444 			    (void *)chk, chk->rec.data.tsn, asoc->last_acked_seq);
445 			if (chk->sent != SCTP_DATAGRAM_NR_ACKED) {
446 				if (asoc->strmout[chk->rec.data.sid].chunks_on_queues > 0) {
447 					asoc->strmout[chk->rec.data.sid].chunks_on_queues--;
448 				}
449 			}
450 			if ((asoc->strmout[chk->rec.data.sid].chunks_on_queues == 0) &&
451 			    (asoc->strmout[chk->rec.data.sid].state == SCTP_STREAM_RESET_PENDING) &&
452 			    TAILQ_EMPTY(&asoc->strmout[chk->rec.data.sid].outqueue)) {
453 				asoc->trigger_reset = 1;
454 			}
455 			TAILQ_REMOVE(&asoc->sent_queue, chk, sctp_next);
456 			if (PR_SCTP_ENABLED(chk->flags)) {
457 				if (asoc->pr_sctp_cnt != 0)
458 					asoc->pr_sctp_cnt--;
459 			}
460 			if (chk->data) {
461 				/* sa_ignore NO_NULL_CHK */
462 				sctp_free_bufspace(stcb, asoc, chk, 1);
463 				sctp_m_freem(chk->data);
464 				chk->data = NULL;
465 				if (asoc->prsctp_supported && PR_SCTP_BUF_ENABLED(chk->flags)) {
466 					asoc->sent_queue_cnt_removeable--;
467 				}
468 			}
469 			asoc->sent_queue_cnt--;
470 			sctp_free_a_chunk(stcb, chk, SCTP_SO_NOT_LOCKED);
471 		}
472 	}
473 	SCTP_PRINTF("after recover order is as follows\n");
474 	TAILQ_FOREACH(chk, &asoc->sent_queue, sctp_next) {
475 		SCTP_PRINTF("chk:%p TSN:%x\n", (void *)chk, chk->rec.data.tsn);
476 	}
477 }
478 #endif
479 
480 static int
sctp_mark_all_for_resend(struct sctp_tcb * stcb,struct sctp_nets * net,struct sctp_nets * alt,int window_probe,int * num_marked,int * num_abandoned)481 sctp_mark_all_for_resend(struct sctp_tcb *stcb,
482     struct sctp_nets *net,
483     struct sctp_nets *alt,
484     int window_probe,
485     int *num_marked,
486     int *num_abandoned)
487 {
488 
489 	/*
490 	 * Mark all chunks (well not all) that were sent to *net for
491 	 * retransmission. Move them to alt for there destination as well...
492 	 * We only mark chunks that have been outstanding long enough to
493 	 * have received feed-back.
494 	 */
495 	struct sctp_tmit_chunk *chk, *nchk;
496 	struct sctp_nets *lnets;
497 	struct timeval now, min_wait, tv;
498 	int cur_rto;
499 	int cnt_abandoned;
500 	int audit_tf, num_mk, fir;
501 	unsigned int cnt_mk;
502 	uint32_t orig_flight, orig_tf;
503 	uint32_t tsnlast, tsnfirst;
504 #ifndef INVARIANTS
505 	int recovery_cnt = 0;
506 #endif
507 
508 	/* none in flight now */
509 	audit_tf = 0;
510 	fir = 0;
511 	/*
512 	 * figure out how long a data chunk must be pending before we can
513 	 * mark it ..
514 	 */
515 	(void)SCTP_GETTIME_TIMEVAL(&now);
516 	/* get cur rto in micro-seconds */
517 	cur_rto = (net->lastsa >> SCTP_RTT_SHIFT) + net->lastsv;
518 	cur_rto *= 1000;
519 	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
520 		sctp_log_fr(cur_rto,
521 		    stcb->asoc.peers_rwnd,
522 		    window_probe,
523 		    SCTP_FR_T3_MARK_TIME);
524 		sctp_log_fr(net->flight_size, 0, 0, SCTP_FR_CWND_REPORT);
525 		sctp_log_fr(net->flight_size, net->cwnd, stcb->asoc.total_flight, SCTP_FR_CWND_REPORT);
526 	}
527 	tv.tv_sec = cur_rto / 1000000;
528 	tv.tv_usec = cur_rto % 1000000;
529 	min_wait = now;
530 	timevalsub(&min_wait, &tv);
531 	if (min_wait.tv_sec < 0 || min_wait.tv_usec < 0) {
532 		/*
533 		 * if we hit here, we don't have enough seconds on the clock
534 		 * to account for the RTO. We just let the lower seconds be
535 		 * the bounds and don't worry about it. This may mean we
536 		 * will mark a lot more than we should.
537 		 */
538 		min_wait.tv_sec = min_wait.tv_usec = 0;
539 	}
540 	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
541 		sctp_log_fr(cur_rto, (uint32_t)now.tv_sec, now.tv_usec, SCTP_FR_T3_MARK_TIME);
542 		sctp_log_fr(0, (uint32_t)min_wait.tv_sec, min_wait.tv_usec, SCTP_FR_T3_MARK_TIME);
543 	}
544 	/*
545 	 * Our rwnd will be incorrect here since we are not adding back the
546 	 * cnt * mbuf but we will fix that down below.
547 	 */
548 	orig_flight = net->flight_size;
549 	orig_tf = stcb->asoc.total_flight;
550 
551 	net->fast_retran_ip = 0;
552 	/* Now on to each chunk */
553 	cnt_abandoned = 0;
554 	num_mk = cnt_mk = 0;
555 	tsnfirst = tsnlast = 0;
556 #ifndef INVARIANTS
557 start_again:
558 #endif
559 	TAILQ_FOREACH_SAFE(chk, &stcb->asoc.sent_queue, sctp_next, nchk) {
560 		if (SCTP_TSN_GE(stcb->asoc.last_acked_seq, chk->rec.data.tsn)) {
561 			/* Strange case our list got out of order? */
562 			SCTP_PRINTF("Our list is out of order? last_acked:%x chk:%x\n",
563 			    (unsigned int)stcb->asoc.last_acked_seq, (unsigned int)chk->rec.data.tsn);
564 #ifdef INVARIANTS
565 			panic("last acked >= chk on sent-Q");
566 #else
567 			recovery_cnt++;
568 			SCTP_PRINTF("Recover attempts a restart cnt:%d\n", recovery_cnt);
569 			sctp_recover_sent_list(stcb);
570 			if (recovery_cnt < 10) {
571 				goto start_again;
572 			} else {
573 				SCTP_PRINTF("Recovery fails %d times??\n", recovery_cnt);
574 			}
575 #endif
576 		}
577 		if ((chk->whoTo == net) && (chk->sent < SCTP_DATAGRAM_ACKED)) {
578 			/*
579 			 * found one to mark: If it is less than
580 			 * DATAGRAM_ACKED it MUST not be a skipped or marked
581 			 * TSN but instead one that is either already set
582 			 * for retransmission OR one that needs
583 			 * retransmission.
584 			 */
585 
586 			/* validate its been outstanding long enough */
587 			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
588 				sctp_log_fr(chk->rec.data.tsn,
589 				    (uint32_t)chk->sent_rcv_time.tv_sec,
590 				    chk->sent_rcv_time.tv_usec,
591 				    SCTP_FR_T3_MARK_TIME);
592 			}
593 			if ((chk->sent_rcv_time.tv_sec > min_wait.tv_sec) && (window_probe == 0)) {
594 				/*
595 				 * we have reached a chunk that was sent
596 				 * some seconds past our min.. forget it we
597 				 * will find no more to send.
598 				 */
599 				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
600 					sctp_log_fr(0,
601 					    (uint32_t)chk->sent_rcv_time.tv_sec,
602 					    chk->sent_rcv_time.tv_usec,
603 					    SCTP_FR_T3_STOPPED);
604 				}
605 				continue;
606 			} else if ((chk->sent_rcv_time.tv_sec == min_wait.tv_sec) &&
607 			    (window_probe == 0)) {
608 				/*
609 				 * we must look at the micro seconds to
610 				 * know.
611 				 */
612 				if (chk->sent_rcv_time.tv_usec >= min_wait.tv_usec) {
613 					/*
614 					 * ok it was sent after our boundary
615 					 * time.
616 					 */
617 					continue;
618 				}
619 			}
620 			if (stcb->asoc.prsctp_supported && PR_SCTP_TTL_ENABLED(chk->flags)) {
621 				/* Is it expired? */
622 				if (timevalcmp(&now, &chk->rec.data.timetodrop, >)) {
623 					/* Yes so drop it */
624 					if (chk->data) {
625 						(void)sctp_release_pr_sctp_chunk(stcb,
626 						    chk,
627 						    1,
628 						    SCTP_SO_NOT_LOCKED);
629 						cnt_abandoned++;
630 					}
631 					continue;
632 				}
633 			}
634 			if (stcb->asoc.prsctp_supported && PR_SCTP_RTX_ENABLED(chk->flags)) {
635 				/* Has it been retransmitted tv_sec times? */
636 				if (chk->snd_count > chk->rec.data.timetodrop.tv_sec) {
637 					if (chk->data) {
638 						(void)sctp_release_pr_sctp_chunk(stcb,
639 						    chk,
640 						    1,
641 						    SCTP_SO_NOT_LOCKED);
642 						cnt_abandoned++;
643 					}
644 					continue;
645 				}
646 			}
647 			if (chk->sent < SCTP_DATAGRAM_RESEND) {
648 				sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
649 				num_mk++;
650 				if (fir == 0) {
651 					fir = 1;
652 					tsnfirst = chk->rec.data.tsn;
653 				}
654 				tsnlast = chk->rec.data.tsn;
655 				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
656 					sctp_log_fr(chk->rec.data.tsn, chk->snd_count,
657 					    0, SCTP_FR_T3_MARKED);
658 				}
659 
660 				if (chk->rec.data.chunk_was_revoked) {
661 					/* deflate the cwnd */
662 					chk->whoTo->cwnd -= chk->book_size;
663 					chk->rec.data.chunk_was_revoked = 0;
664 				}
665 				net->marked_retrans++;
666 				stcb->asoc.marked_retrans++;
667 				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FLIGHT_LOGGING_ENABLE) {
668 					sctp_misc_ints(SCTP_FLIGHT_LOG_DOWN_RSND_TO,
669 					    chk->whoTo->flight_size,
670 					    chk->book_size,
671 					    (uint32_t)(uintptr_t)chk->whoTo,
672 					    chk->rec.data.tsn);
673 				}
674 				sctp_flight_size_decrease(chk);
675 				sctp_total_flight_decrease(stcb, chk);
676 				stcb->asoc.peers_rwnd += chk->send_size;
677 				stcb->asoc.peers_rwnd += SCTP_BASE_SYSCTL(sctp_peer_chunk_oh);
678 			}
679 			chk->sent = SCTP_DATAGRAM_RESEND;
680 			chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
681 			SCTP_STAT_INCR(sctps_markedretrans);
682 
683 			/* reset the TSN for striking and other FR stuff */
684 			chk->rec.data.doing_fast_retransmit = 0;
685 			/* Clear any time so NO RTT is being done */
686 
687 			if (chk->do_rtt) {
688 				if (chk->whoTo->rto_needed == 0) {
689 					chk->whoTo->rto_needed = 1;
690 				}
691 			}
692 			chk->do_rtt = 0;
693 			if (alt != net) {
694 				sctp_free_remote_addr(chk->whoTo);
695 				chk->no_fr_allowed = 1;
696 				chk->whoTo = alt;
697 				atomic_add_int(&alt->ref_count, 1);
698 			} else {
699 				chk->no_fr_allowed = 0;
700 				if (TAILQ_EMPTY(&stcb->asoc.send_queue)) {
701 					chk->rec.data.fast_retran_tsn = stcb->asoc.sending_seq;
702 				} else {
703 					chk->rec.data.fast_retran_tsn = (TAILQ_FIRST(&stcb->asoc.send_queue))->rec.data.tsn;
704 				}
705 			}
706 			/*
707 			 * CMT: Do not allow FRs on retransmitted TSNs.
708 			 */
709 			if (stcb->asoc.sctp_cmt_on_off > 0) {
710 				chk->no_fr_allowed = 1;
711 			}
712 #ifdef THIS_SHOULD_NOT_BE_DONE
713 		} else if (chk->sent == SCTP_DATAGRAM_ACKED) {
714 			/* remember highest acked one */
715 			could_be_sent = chk;
716 #endif
717 		}
718 		if (chk->sent == SCTP_DATAGRAM_RESEND) {
719 			cnt_mk++;
720 		}
721 	}
722 	if ((orig_flight - net->flight_size) != (orig_tf - stcb->asoc.total_flight)) {
723 		/* we did not subtract the same things? */
724 		audit_tf = 1;
725 	}
726 
727 	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
728 		sctp_log_fr(tsnfirst, tsnlast, num_mk, SCTP_FR_T3_TIMEOUT);
729 	}
730 #ifdef SCTP_DEBUG
731 	if (num_mk) {
732 		SCTPDBG(SCTP_DEBUG_TIMER1, "LAST TSN marked was %x\n",
733 		    tsnlast);
734 		SCTPDBG(SCTP_DEBUG_TIMER1, "Num marked for retransmission was %d peer-rwd:%u\n",
735 		    num_mk,
736 		    stcb->asoc.peers_rwnd);
737 	}
738 #endif
739 	*num_marked = num_mk;
740 	*num_abandoned = cnt_abandoned;
741 	/*
742 	 * Now check for a ECN Echo that may be stranded And include the
743 	 * cnt_mk'd to have all resends in the control queue.
744 	 */
745 	TAILQ_FOREACH(chk, &stcb->asoc.control_send_queue, sctp_next) {
746 		if (chk->sent == SCTP_DATAGRAM_RESEND) {
747 			cnt_mk++;
748 		}
749 		if ((chk->whoTo == net) &&
750 		    (chk->rec.chunk_id.id == SCTP_ECN_ECHO)) {
751 			sctp_free_remote_addr(chk->whoTo);
752 			chk->whoTo = alt;
753 			if (chk->sent != SCTP_DATAGRAM_RESEND) {
754 				chk->sent = SCTP_DATAGRAM_RESEND;
755 				chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
756 				sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
757 				cnt_mk++;
758 			}
759 			atomic_add_int(&alt->ref_count, 1);
760 		}
761 	}
762 #ifdef THIS_SHOULD_NOT_BE_DONE
763 	if ((stcb->asoc.sent_queue_retran_cnt == 0) && (could_be_sent)) {
764 		/* fix it so we retransmit the highest acked anyway */
765 		sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
766 		cnt_mk++;
767 		could_be_sent->sent = SCTP_DATAGRAM_RESEND;
768 	}
769 #endif
770 	if (stcb->asoc.sent_queue_retran_cnt != cnt_mk) {
771 #ifdef INVARIANTS
772 		SCTP_PRINTF("Local Audit says there are %d for retran asoc cnt:%d we marked:%d this time\n",
773 		    cnt_mk, stcb->asoc.sent_queue_retran_cnt, num_mk);
774 #endif
775 #ifndef SCTP_AUDITING_ENABLED
776 		stcb->asoc.sent_queue_retran_cnt = cnt_mk;
777 #endif
778 	}
779 	if (audit_tf) {
780 		SCTPDBG(SCTP_DEBUG_TIMER4,
781 		    "Audit total flight due to negative value net:%p\n",
782 		    (void *)net);
783 		stcb->asoc.total_flight = 0;
784 		stcb->asoc.total_flight_count = 0;
785 		/* Clear all networks flight size */
786 		TAILQ_FOREACH(lnets, &stcb->asoc.nets, sctp_next) {
787 			lnets->flight_size = 0;
788 			SCTPDBG(SCTP_DEBUG_TIMER4,
789 			    "Net:%p c-f cwnd:%d ssthresh:%d\n",
790 			    (void *)lnets, lnets->cwnd, lnets->ssthresh);
791 		}
792 		TAILQ_FOREACH(chk, &stcb->asoc.sent_queue, sctp_next) {
793 			if (chk->sent < SCTP_DATAGRAM_RESEND) {
794 				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FLIGHT_LOGGING_ENABLE) {
795 					sctp_misc_ints(SCTP_FLIGHT_LOG_UP,
796 					    chk->whoTo->flight_size,
797 					    chk->book_size,
798 					    (uint32_t)(uintptr_t)chk->whoTo,
799 					    chk->rec.data.tsn);
800 				}
801 
802 				sctp_flight_size_increase(chk);
803 				sctp_total_flight_increase(stcb, chk);
804 			}
805 		}
806 	}
807 	/* We return 1 if we only have a window probe outstanding */
808 	return (0);
809 }
810 
811 int
sctp_t3rxt_timer(struct sctp_inpcb * inp,struct sctp_tcb * stcb,struct sctp_nets * net)812 sctp_t3rxt_timer(struct sctp_inpcb *inp,
813     struct sctp_tcb *stcb,
814     struct sctp_nets *net)
815 {
816 	struct sctp_nets *alt;
817 	int win_probe, num_mk, num_abandoned;
818 
819 	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
820 		sctp_log_fr(0, 0, 0, SCTP_FR_T3_TIMEOUT);
821 	}
822 	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
823 		struct sctp_nets *lnet;
824 
825 		TAILQ_FOREACH(lnet, &stcb->asoc.nets, sctp_next) {
826 			if (net == lnet) {
827 				sctp_log_cwnd(stcb, lnet, 1, SCTP_CWND_LOG_FROM_T3);
828 			} else {
829 				sctp_log_cwnd(stcb, lnet, 0, SCTP_CWND_LOG_FROM_T3);
830 			}
831 		}
832 	}
833 	/* Find an alternate and mark those for retransmission */
834 	if ((stcb->asoc.peers_rwnd == 0) &&
835 	    (stcb->asoc.total_flight < net->mtu)) {
836 		SCTP_STAT_INCR(sctps_timowindowprobe);
837 		win_probe = 1;
838 	} else {
839 		win_probe = 0;
840 	}
841 
842 	if (win_probe == 0) {
843 		/* We don't do normal threshold management on window probes */
844 		if (sctp_threshold_management(inp, stcb, net,
845 		    stcb->asoc.max_send_times)) {
846 			/* Association was destroyed */
847 			return (1);
848 		} else {
849 			if (net != stcb->asoc.primary_destination) {
850 				/* send a immediate HB if our RTO is stale */
851 				struct timeval now;
852 				uint32_t ms_goneby;
853 
854 				(void)SCTP_GETTIME_TIMEVAL(&now);
855 				if (net->last_sent_time.tv_sec) {
856 					ms_goneby = (uint32_t)(now.tv_sec - net->last_sent_time.tv_sec) * 1000;
857 				} else {
858 					ms_goneby = 0;
859 				}
860 				if ((net->dest_state & SCTP_ADDR_PF) == 0) {
861 					if ((ms_goneby > net->RTO) || (net->RTO == 0)) {
862 						/*
863 						 * no recent feed back in an
864 						 * RTO or more, request a
865 						 * RTT update
866 						 */
867 						sctp_send_hb(stcb, net, SCTP_SO_NOT_LOCKED);
868 					}
869 				}
870 			}
871 		}
872 	} else {
873 		/*
874 		 * For a window probe we don't penalize the net's but only
875 		 * the association. This may fail it if SACKs are not coming
876 		 * back. If sack's are coming with rwnd locked at 0, we will
877 		 * continue to hold things waiting for rwnd to raise
878 		 */
879 		if (sctp_threshold_management(inp, stcb, NULL,
880 		    stcb->asoc.max_send_times)) {
881 			/* Association was destroyed */
882 			return (1);
883 		}
884 	}
885 	if (stcb->asoc.sctp_cmt_on_off > 0) {
886 		if (net->pf_threshold < net->failure_threshold) {
887 			alt = sctp_find_alternate_net(stcb, net, 2);
888 		} else {
889 			/*
890 			 * CMT: Using RTX_SSTHRESH policy for CMT. If CMT is
891 			 * being used, then pick dest with largest ssthresh
892 			 * for any retransmission.
893 			 */
894 			alt = sctp_find_alternate_net(stcb, net, 1);
895 			/*
896 			 * CUCv2: If a different dest is picked for the
897 			 * retransmission, then new (rtx-)pseudo_cumack
898 			 * needs to be tracked for orig dest. Let CUCv2
899 			 * track new (rtx-) pseudo-cumack always.
900 			 */
901 			net->find_pseudo_cumack = 1;
902 			net->find_rtx_pseudo_cumack = 1;
903 		}
904 	} else {
905 		alt = sctp_find_alternate_net(stcb, net, 0);
906 	}
907 
908 	num_mk = 0;
909 	num_abandoned = 0;
910 	(void)sctp_mark_all_for_resend(stcb, net, alt, win_probe,
911 	    &num_mk, &num_abandoned);
912 	/* FR Loss recovery just ended with the T3. */
913 	stcb->asoc.fast_retran_loss_recovery = 0;
914 
915 	/* CMT FR loss recovery ended with the T3 */
916 	net->fast_retran_loss_recovery = 0;
917 	if ((stcb->asoc.cc_functions.sctp_cwnd_new_transmission_begins) &&
918 	    (net->flight_size == 0)) {
919 		(*stcb->asoc.cc_functions.sctp_cwnd_new_transmission_begins) (stcb, net);
920 	}
921 
922 	/*
923 	 * setup the sat loss recovery that prevents satellite cwnd advance.
924 	 */
925 	stcb->asoc.sat_t3_loss_recovery = 1;
926 	stcb->asoc.sat_t3_recovery_tsn = stcb->asoc.sending_seq;
927 
928 	/* Backoff the timer and cwnd */
929 	sctp_backoff_on_timeout(stcb, net, win_probe, num_mk, num_abandoned);
930 	if (((net->dest_state & SCTP_ADDR_REACHABLE) == 0) ||
931 	    (net->dest_state & SCTP_ADDR_PF)) {
932 		/* Move all pending over too */
933 		sctp_move_chunks_from_net(stcb, net);
934 
935 		/*
936 		 * Get the address that failed, to force a new src address
937 		 * selection and a route allocation.
938 		 */
939 		if (net->ro._s_addr != NULL) {
940 			sctp_free_ifa(net->ro._s_addr);
941 			net->ro._s_addr = NULL;
942 		}
943 		net->src_addr_selected = 0;
944 
945 		/* Force a route allocation too */
946 		RO_NHFREE(&net->ro);
947 
948 		/* Was it our primary? */
949 		if ((stcb->asoc.primary_destination == net) && (alt != net)) {
950 			/*
951 			 * Yes, note it as such and find an alternate note:
952 			 * this means HB code must use this to resent the
953 			 * primary if it goes active AND if someone does a
954 			 * change-primary then this flag must be cleared
955 			 * from any net structures.
956 			 */
957 			if (stcb->asoc.alternate != NULL) {
958 				sctp_free_remote_addr(stcb->asoc.alternate);
959 			}
960 			stcb->asoc.alternate = alt;
961 			atomic_add_int(&stcb->asoc.alternate->ref_count, 1);
962 		}
963 	}
964 	/*
965 	 * Special case for cookie-echo'ed case, we don't do output but must
966 	 * await the COOKIE-ACK before retransmission
967 	 */
968 	if (SCTP_GET_STATE(stcb) == SCTP_STATE_COOKIE_ECHOED) {
969 		/*
970 		 * Here we just reset the timer and start again since we
971 		 * have not established the asoc
972 		 */
973 		sctp_timer_start(SCTP_TIMER_TYPE_SEND, inp, stcb, net);
974 		return (0);
975 	}
976 	if (stcb->asoc.prsctp_supported) {
977 		struct sctp_tmit_chunk *lchk;
978 
979 		lchk = sctp_try_advance_peer_ack_point(stcb, &stcb->asoc);
980 		/* C3. See if we need to send a Fwd-TSN */
981 		if (SCTP_TSN_GT(stcb->asoc.advanced_peer_ack_point, stcb->asoc.last_acked_seq)) {
982 			send_forward_tsn(stcb, &stcb->asoc);
983 			for (; lchk != NULL; lchk = TAILQ_NEXT(lchk, sctp_next)) {
984 				if (lchk->whoTo != NULL) {
985 					break;
986 				}
987 			}
988 			if (lchk != NULL) {
989 				/* Assure a timer is up */
990 				sctp_timer_start(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep, stcb, lchk->whoTo);
991 			}
992 		}
993 	}
994 	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
995 		sctp_log_cwnd(stcb, net, net->cwnd, SCTP_CWND_LOG_FROM_RTX);
996 	}
997 	return (0);
998 }
999 
1000 int
sctp_t1init_timer(struct sctp_inpcb * inp,struct sctp_tcb * stcb,struct sctp_nets * net)1001 sctp_t1init_timer(struct sctp_inpcb *inp,
1002     struct sctp_tcb *stcb,
1003     struct sctp_nets *net)
1004 {
1005 	/* bump the thresholds */
1006 	if (stcb->asoc.delayed_connection) {
1007 		/*
1008 		 * special hook for delayed connection. The library did NOT
1009 		 * complete the rest of its sends.
1010 		 */
1011 		stcb->asoc.delayed_connection = 0;
1012 		sctp_send_initiate(inp, stcb, SCTP_SO_NOT_LOCKED);
1013 		return (0);
1014 	}
1015 	if (SCTP_GET_STATE(stcb) != SCTP_STATE_COOKIE_WAIT) {
1016 		return (0);
1017 	}
1018 	if (sctp_threshold_management(inp, stcb, net,
1019 	    stcb->asoc.max_init_times)) {
1020 		/* Association was destroyed */
1021 		return (1);
1022 	}
1023 	stcb->asoc.dropped_special_cnt = 0;
1024 	sctp_backoff_on_timeout(stcb, stcb->asoc.primary_destination, 1, 0, 0);
1025 	if (stcb->asoc.initial_init_rto_max < net->RTO) {
1026 		net->RTO = stcb->asoc.initial_init_rto_max;
1027 	}
1028 	if (stcb->asoc.numnets > 1) {
1029 		/* If we have more than one addr use it */
1030 		struct sctp_nets *alt;
1031 
1032 		alt = sctp_find_alternate_net(stcb, stcb->asoc.primary_destination, 0);
1033 		if (alt != stcb->asoc.primary_destination) {
1034 			sctp_move_chunks_from_net(stcb, stcb->asoc.primary_destination);
1035 			stcb->asoc.primary_destination = alt;
1036 		}
1037 	}
1038 	/* Send out a new init */
1039 	sctp_send_initiate(inp, stcb, SCTP_SO_NOT_LOCKED);
1040 	return (0);
1041 }
1042 
1043 /*
1044  * For cookie and asconf we actually need to find and mark for resend, then
1045  * increment the resend counter (after all the threshold management stuff of
1046  * course).
1047  */
1048 int
sctp_cookie_timer(struct sctp_inpcb * inp,struct sctp_tcb * stcb,struct sctp_nets * net SCTP_UNUSED)1049 sctp_cookie_timer(struct sctp_inpcb *inp,
1050     struct sctp_tcb *stcb,
1051     struct sctp_nets *net SCTP_UNUSED)
1052 {
1053 	struct sctp_nets *alt;
1054 	struct sctp_tmit_chunk *cookie;
1055 
1056 	/* first before all else we must find the cookie */
1057 	TAILQ_FOREACH(cookie, &stcb->asoc.control_send_queue, sctp_next) {
1058 		if (cookie->rec.chunk_id.id == SCTP_COOKIE_ECHO) {
1059 			break;
1060 		}
1061 	}
1062 	if (cookie == NULL) {
1063 		if (SCTP_GET_STATE(stcb) == SCTP_STATE_COOKIE_ECHOED) {
1064 			/* FOOBAR! */
1065 			struct mbuf *op_err;
1066 
1067 			op_err = sctp_generate_cause(SCTP_BASE_SYSCTL(sctp_diag_info_code),
1068 			    "Cookie timer expired, but no cookie");
1069 			inp->last_abort_code = SCTP_FROM_SCTP_TIMER + SCTP_LOC_3;
1070 			sctp_abort_an_association(inp, stcb, op_err, false, SCTP_SO_NOT_LOCKED);
1071 		} else {
1072 #ifdef INVARIANTS
1073 			panic("Cookie timer expires in wrong state?");
1074 #else
1075 			SCTP_PRINTF("Strange in state %d not cookie-echoed yet c-e timer expires?\n", SCTP_GET_STATE(stcb));
1076 			return (0);
1077 #endif
1078 		}
1079 		return (0);
1080 	}
1081 	/* Ok we found the cookie, threshold management next */
1082 	if (sctp_threshold_management(inp, stcb, cookie->whoTo,
1083 	    stcb->asoc.max_init_times)) {
1084 		/* Assoc is over */
1085 		return (1);
1086 	}
1087 	/*
1088 	 * Cleared threshold management, now lets backoff the address and
1089 	 * select an alternate
1090 	 */
1091 	stcb->asoc.dropped_special_cnt = 0;
1092 	sctp_backoff_on_timeout(stcb, cookie->whoTo, 1, 0, 0);
1093 	alt = sctp_find_alternate_net(stcb, cookie->whoTo, 0);
1094 	if (alt != cookie->whoTo) {
1095 		sctp_free_remote_addr(cookie->whoTo);
1096 		cookie->whoTo = alt;
1097 		atomic_add_int(&alt->ref_count, 1);
1098 	}
1099 	/* Now mark the retran info */
1100 	if (cookie->sent != SCTP_DATAGRAM_RESEND) {
1101 		sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
1102 	}
1103 	cookie->sent = SCTP_DATAGRAM_RESEND;
1104 	cookie->flags |= CHUNK_FLAGS_FRAGMENT_OK;
1105 	/*
1106 	 * Now call the output routine to kick out the cookie again, Note we
1107 	 * don't mark any chunks for retran so that FR will need to kick in
1108 	 * to move these (or a send timer).
1109 	 */
1110 	return (0);
1111 }
1112 
1113 int
sctp_strreset_timer(struct sctp_inpcb * inp,struct sctp_tcb * stcb)1114 sctp_strreset_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
1115 {
1116 	struct sctp_nets *alt, *net;
1117 	struct sctp_tmit_chunk *strrst = NULL, *chk = NULL;
1118 
1119 	if (stcb->asoc.stream_reset_outstanding == 0) {
1120 		return (0);
1121 	}
1122 	/* find the existing STRRESET, we use the seq number we sent out on */
1123 	(void)sctp_find_stream_reset(stcb, stcb->asoc.str_reset_seq_out, &strrst);
1124 	if (strrst == NULL) {
1125 		return (0);
1126 	}
1127 	net = strrst->whoTo;
1128 	/* do threshold management */
1129 	if (sctp_threshold_management(inp, stcb, net, stcb->asoc.max_send_times)) {
1130 		/* Assoc is over */
1131 		return (1);
1132 	}
1133 	/*
1134 	 * Cleared threshold management, now lets backoff the address and
1135 	 * select an alternate
1136 	 */
1137 	sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
1138 	alt = sctp_find_alternate_net(stcb, net, 0);
1139 	strrst->whoTo = alt;
1140 	atomic_add_int(&alt->ref_count, 1);
1141 
1142 	/* See if a ECN Echo is also stranded */
1143 	TAILQ_FOREACH(chk, &stcb->asoc.control_send_queue, sctp_next) {
1144 		if ((chk->whoTo == net) &&
1145 		    (chk->rec.chunk_id.id == SCTP_ECN_ECHO)) {
1146 			sctp_free_remote_addr(chk->whoTo);
1147 			if (chk->sent != SCTP_DATAGRAM_RESEND) {
1148 				chk->sent = SCTP_DATAGRAM_RESEND;
1149 				chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
1150 				sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
1151 			}
1152 			chk->whoTo = alt;
1153 			atomic_add_int(&alt->ref_count, 1);
1154 		}
1155 	}
1156 	if ((net->dest_state & SCTP_ADDR_REACHABLE) == 0) {
1157 		/*
1158 		 * If the address went un-reachable, we need to move to
1159 		 * alternates for ALL chk's in queue
1160 		 */
1161 		sctp_move_chunks_from_net(stcb, net);
1162 	}
1163 	sctp_free_remote_addr(net);
1164 
1165 	/* mark the retran info */
1166 	if (strrst->sent != SCTP_DATAGRAM_RESEND)
1167 		sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
1168 	strrst->sent = SCTP_DATAGRAM_RESEND;
1169 	strrst->flags |= CHUNK_FLAGS_FRAGMENT_OK;
1170 
1171 	/* restart the timer */
1172 	sctp_timer_start(SCTP_TIMER_TYPE_STRRESET, inp, stcb, alt);
1173 	return (0);
1174 }
1175 
1176 int
sctp_asconf_timer(struct sctp_inpcb * inp,struct sctp_tcb * stcb,struct sctp_nets * net)1177 sctp_asconf_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb,
1178     struct sctp_nets *net)
1179 {
1180 	struct sctp_nets *alt;
1181 	struct sctp_tmit_chunk *asconf, *chk;
1182 
1183 	/* is this a first send, or a retransmission? */
1184 	if (TAILQ_EMPTY(&stcb->asoc.asconf_send_queue)) {
1185 		/* compose a new ASCONF chunk and send it */
1186 		sctp_send_asconf(stcb, net, SCTP_ADDR_NOT_LOCKED);
1187 	} else {
1188 		/*
1189 		 * Retransmission of the existing ASCONF is needed
1190 		 */
1191 
1192 		/* find the existing ASCONF */
1193 		asconf = TAILQ_FIRST(&stcb->asoc.asconf_send_queue);
1194 		if (asconf == NULL) {
1195 			return (0);
1196 		}
1197 		net = asconf->whoTo;
1198 		/* do threshold management */
1199 		if (sctp_threshold_management(inp, stcb, net,
1200 		    stcb->asoc.max_send_times)) {
1201 			/* Assoc is over */
1202 			return (1);
1203 		}
1204 		if (asconf->snd_count > stcb->asoc.max_send_times) {
1205 			/*
1206 			 * Something is rotten: our peer is not responding
1207 			 * to ASCONFs but apparently is to other chunks.
1208 			 * i.e. it is not properly handling the chunk type
1209 			 * upper bits. Mark this peer as ASCONF incapable
1210 			 * and cleanup.
1211 			 */
1212 			SCTPDBG(SCTP_DEBUG_TIMER1, "asconf_timer: Peer has not responded to our repeated ASCONFs\n");
1213 			sctp_asconf_cleanup(stcb);
1214 			return (0);
1215 		}
1216 		/*
1217 		 * cleared threshold management, so now backoff the net and
1218 		 * select an alternate
1219 		 */
1220 		sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
1221 		alt = sctp_find_alternate_net(stcb, net, 0);
1222 		if (asconf->whoTo != alt) {
1223 			asconf->whoTo = alt;
1224 			atomic_add_int(&alt->ref_count, 1);
1225 		}
1226 
1227 		/* See if an ECN Echo is also stranded */
1228 		TAILQ_FOREACH(chk, &stcb->asoc.control_send_queue, sctp_next) {
1229 			if ((chk->whoTo == net) &&
1230 			    (chk->rec.chunk_id.id == SCTP_ECN_ECHO)) {
1231 				sctp_free_remote_addr(chk->whoTo);
1232 				chk->whoTo = alt;
1233 				if (chk->sent != SCTP_DATAGRAM_RESEND) {
1234 					chk->sent = SCTP_DATAGRAM_RESEND;
1235 					chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
1236 					sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
1237 				}
1238 				atomic_add_int(&alt->ref_count, 1);
1239 			}
1240 		}
1241 		TAILQ_FOREACH(chk, &stcb->asoc.asconf_send_queue, sctp_next) {
1242 			if (chk->whoTo != alt) {
1243 				sctp_free_remote_addr(chk->whoTo);
1244 				chk->whoTo = alt;
1245 				atomic_add_int(&alt->ref_count, 1);
1246 			}
1247 			if (asconf->sent != SCTP_DATAGRAM_RESEND && chk->sent != SCTP_DATAGRAM_UNSENT)
1248 				sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
1249 			chk->sent = SCTP_DATAGRAM_RESEND;
1250 			chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
1251 		}
1252 		if ((net->dest_state & SCTP_ADDR_REACHABLE) == 0) {
1253 			/*
1254 			 * If the address went un-reachable, we need to move
1255 			 * to the alternate for ALL chunks in queue
1256 			 */
1257 			sctp_move_chunks_from_net(stcb, net);
1258 		}
1259 		sctp_free_remote_addr(net);
1260 
1261 		/* mark the retran info */
1262 		if (asconf->sent != SCTP_DATAGRAM_RESEND)
1263 			sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
1264 		asconf->sent = SCTP_DATAGRAM_RESEND;
1265 		asconf->flags |= CHUNK_FLAGS_FRAGMENT_OK;
1266 
1267 		/* send another ASCONF if any and we can do */
1268 		sctp_send_asconf(stcb, alt, SCTP_ADDR_NOT_LOCKED);
1269 	}
1270 	return (0);
1271 }
1272 
1273 /* Mobility adaptation */
1274 void
sctp_delete_prim_timer(struct sctp_inpcb * inp,struct sctp_tcb * stcb)1275 sctp_delete_prim_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
1276 {
1277 	if (stcb->asoc.deleted_primary == NULL) {
1278 		SCTPDBG(SCTP_DEBUG_ASCONF1, "delete_prim_timer: deleted_primary is not stored...\n");
1279 		sctp_mobility_feature_off(inp, SCTP_MOBILITY_PRIM_DELETED);
1280 		return;
1281 	}
1282 	SCTPDBG(SCTP_DEBUG_ASCONF1, "delete_prim_timer: finished to keep deleted primary ");
1283 	SCTPDBG_ADDR(SCTP_DEBUG_ASCONF1, &stcb->asoc.deleted_primary->ro._l_addr.sa);
1284 	sctp_free_remote_addr(stcb->asoc.deleted_primary);
1285 	stcb->asoc.deleted_primary = NULL;
1286 	sctp_mobility_feature_off(inp, SCTP_MOBILITY_PRIM_DELETED);
1287 	return;
1288 }
1289 
1290 /*
1291  * For the shutdown and shutdown-ack, we do not keep one around on the
1292  * control queue. This means we must generate a new one and call the general
1293  * chunk output routine, AFTER having done threshold management.
1294  * It is assumed that net is non-NULL.
1295  */
1296 int
sctp_shutdown_timer(struct sctp_inpcb * inp,struct sctp_tcb * stcb,struct sctp_nets * net)1297 sctp_shutdown_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb,
1298     struct sctp_nets *net)
1299 {
1300 	struct sctp_nets *alt;
1301 
1302 	/* first threshold management */
1303 	if (sctp_threshold_management(inp, stcb, net, stcb->asoc.max_send_times)) {
1304 		/* Assoc is over */
1305 		return (1);
1306 	}
1307 	sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
1308 	/* second select an alternative */
1309 	alt = sctp_find_alternate_net(stcb, net, 0);
1310 
1311 	/* third generate a shutdown into the queue for out net */
1312 	sctp_send_shutdown(stcb, alt);
1313 
1314 	/* fourth restart timer */
1315 	sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWN, inp, stcb, alt);
1316 	return (0);
1317 }
1318 
1319 int
sctp_shutdownack_timer(struct sctp_inpcb * inp,struct sctp_tcb * stcb,struct sctp_nets * net)1320 sctp_shutdownack_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb,
1321     struct sctp_nets *net)
1322 {
1323 	struct sctp_nets *alt;
1324 
1325 	/* first threshold management */
1326 	if (sctp_threshold_management(inp, stcb, net, stcb->asoc.max_send_times)) {
1327 		/* Assoc is over */
1328 		return (1);
1329 	}
1330 	sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
1331 	/* second select an alternative */
1332 	alt = sctp_find_alternate_net(stcb, net, 0);
1333 
1334 	/* third generate a shutdown into the queue for out net */
1335 	sctp_send_shutdown_ack(stcb, alt);
1336 
1337 	/* fourth restart timer */
1338 	sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNACK, inp, stcb, alt);
1339 	return (0);
1340 }
1341 
1342 static void
sctp_audit_stream_queues_for_size(struct sctp_inpcb * inp,struct sctp_tcb * stcb)1343 sctp_audit_stream_queues_for_size(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
1344 {
1345 	struct sctp_stream_queue_pending *sp;
1346 	unsigned int i, chks_in_queue = 0;
1347 	int being_filled = 0;
1348 
1349 	KASSERT(inp != NULL, ("inp is NULL"));
1350 	KASSERT(stcb != NULL, ("stcb is NULL"));
1351 	SCTP_TCB_LOCK_ASSERT(stcb);
1352 	KASSERT(TAILQ_EMPTY(&stcb->asoc.send_queue), ("send_queue not empty"));
1353 	KASSERT(TAILQ_EMPTY(&stcb->asoc.sent_queue), ("sent_queue not empty"));
1354 
1355 	if (stcb->asoc.sent_queue_retran_cnt) {
1356 		SCTP_PRINTF("Hmm, sent_queue_retran_cnt is non-zero %d\n",
1357 		    stcb->asoc.sent_queue_retran_cnt);
1358 		stcb->asoc.sent_queue_retran_cnt = 0;
1359 	}
1360 	if (stcb->asoc.ss_functions.sctp_ss_is_empty(stcb, &stcb->asoc)) {
1361 		/* No stream scheduler information, initialize scheduler */
1362 		stcb->asoc.ss_functions.sctp_ss_init(stcb, &stcb->asoc);
1363 		if (!stcb->asoc.ss_functions.sctp_ss_is_empty(stcb, &stcb->asoc)) {
1364 			/* yep, we lost a stream or two */
1365 			SCTP_PRINTF("Found additional streams NOT managed by scheduler, corrected\n");
1366 		} else {
1367 			/* no streams lost */
1368 			stcb->asoc.total_output_queue_size = 0;
1369 		}
1370 	}
1371 	/* Check to see if some data queued, if so report it */
1372 	for (i = 0; i < stcb->asoc.streamoutcnt; i++) {
1373 		if (!TAILQ_EMPTY(&stcb->asoc.strmout[i].outqueue)) {
1374 			TAILQ_FOREACH(sp, &stcb->asoc.strmout[i].outqueue, next) {
1375 				if (sp->msg_is_complete)
1376 					being_filled++;
1377 				chks_in_queue++;
1378 			}
1379 		}
1380 	}
1381 	if (chks_in_queue != stcb->asoc.stream_queue_cnt) {
1382 		SCTP_PRINTF("Hmm, stream queue cnt at %d I counted %d in stream out wheel\n",
1383 		    stcb->asoc.stream_queue_cnt, chks_in_queue);
1384 	}
1385 	if (chks_in_queue) {
1386 		/* call the output queue function */
1387 		sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_T3, SCTP_SO_NOT_LOCKED);
1388 		if ((TAILQ_EMPTY(&stcb->asoc.send_queue)) &&
1389 		    (TAILQ_EMPTY(&stcb->asoc.sent_queue))) {
1390 			/*
1391 			 * Probably should go in and make it go back through
1392 			 * and add fragments allowed
1393 			 */
1394 			if (being_filled == 0) {
1395 				SCTP_PRINTF("Still nothing moved %d chunks are stuck\n",
1396 				    chks_in_queue);
1397 			}
1398 		}
1399 	} else {
1400 		SCTP_PRINTF("Found no chunks on any queue tot:%lu\n",
1401 		    (u_long)stcb->asoc.total_output_queue_size);
1402 		stcb->asoc.total_output_queue_size = 0;
1403 	}
1404 }
1405 
1406 int
sctp_heartbeat_timer(struct sctp_inpcb * inp,struct sctp_tcb * stcb,struct sctp_nets * net)1407 sctp_heartbeat_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb,
1408     struct sctp_nets *net)
1409 {
1410 	bool net_was_pf;
1411 
1412 	net_was_pf = (net->dest_state & SCTP_ADDR_PF) != 0;
1413 	if (net->hb_responded == 0) {
1414 		if (net->ro._s_addr != NULL) {
1415 			/*
1416 			 * Invalidate the src address if we did not get a
1417 			 * response last time.
1418 			 */
1419 			sctp_free_ifa(net->ro._s_addr);
1420 			net->ro._s_addr = NULL;
1421 			net->src_addr_selected = 0;
1422 		}
1423 		sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
1424 		if (sctp_threshold_management(inp, stcb, net, stcb->asoc.max_send_times)) {
1425 			/* Assoc is over */
1426 			return (1);
1427 		}
1428 	}
1429 	/* Zero PBA, if it needs it */
1430 	if (net->partial_bytes_acked > 0) {
1431 		net->partial_bytes_acked = 0;
1432 	}
1433 	if ((stcb->asoc.total_output_queue_size > 0) &&
1434 	    (TAILQ_EMPTY(&stcb->asoc.send_queue)) &&
1435 	    (TAILQ_EMPTY(&stcb->asoc.sent_queue))) {
1436 		sctp_audit_stream_queues_for_size(inp, stcb);
1437 	}
1438 	if ((((net->dest_state & SCTP_ADDR_NOHB) == 0) ||
1439 	    (net->dest_state & SCTP_ADDR_UNCONFIRMED)) &&
1440 	    (net_was_pf || ((net->dest_state & SCTP_ADDR_PF) == 0))) {
1441 		/*
1442 		 * When moving to PF during threshold management, a HB has
1443 		 * been queued in that routine.
1444 		 */
1445 		uint32_t ms_gone_by;
1446 
1447 		if ((net->last_sent_time.tv_sec > 0) ||
1448 		    (net->last_sent_time.tv_usec > 0)) {
1449 			struct timeval diff;
1450 
1451 			SCTP_GETTIME_TIMEVAL(&diff);
1452 			timevalsub(&diff, &net->last_sent_time);
1453 			ms_gone_by = (uint32_t)(diff.tv_sec * 1000) +
1454 			    (uint32_t)(diff.tv_usec / 1000);
1455 		} else {
1456 			ms_gone_by = 0xffffffff;
1457 		}
1458 		if ((ms_gone_by >= net->heart_beat_delay) ||
1459 		    (net->dest_state & SCTP_ADDR_UNCONFIRMED) ||
1460 		    (net->dest_state & SCTP_ADDR_PF)) {
1461 			sctp_send_hb(stcb, net, SCTP_SO_NOT_LOCKED);
1462 		}
1463 	}
1464 	return (0);
1465 }
1466 
1467 void
sctp_pathmtu_timer(struct sctp_inpcb * inp,struct sctp_tcb * stcb,struct sctp_nets * net)1468 sctp_pathmtu_timer(struct sctp_inpcb *inp,
1469     struct sctp_tcb *stcb,
1470     struct sctp_nets *net)
1471 {
1472 	uint32_t next_mtu, mtu;
1473 
1474 	next_mtu = sctp_get_next_mtu(net->mtu);
1475 
1476 	if ((next_mtu > net->mtu) && (net->port == 0)) {
1477 		if ((net->src_addr_selected == 0) ||
1478 		    (net->ro._s_addr == NULL) ||
1479 		    (net->ro._s_addr->localifa_flags & SCTP_BEING_DELETED)) {
1480 			if ((net->ro._s_addr != NULL) && (net->ro._s_addr->localifa_flags & SCTP_BEING_DELETED)) {
1481 				sctp_free_ifa(net->ro._s_addr);
1482 				net->ro._s_addr = NULL;
1483 				net->src_addr_selected = 0;
1484 			} else if (net->ro._s_addr == NULL) {
1485 #if defined(INET6) && defined(SCTP_EMBEDDED_V6_SCOPE)
1486 				if (net->ro._l_addr.sa.sa_family == AF_INET6) {
1487 					struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&net->ro._l_addr;
1488 
1489 					/* KAME hack: embed scopeid */
1490 					(void)sa6_embedscope(sin6, MODULE_GLOBAL(ip6_use_defzone));
1491 				}
1492 #endif
1493 
1494 				net->ro._s_addr = sctp_source_address_selection(inp,
1495 				    stcb,
1496 				    (sctp_route_t *)&net->ro,
1497 				    net, 0, stcb->asoc.vrf_id);
1498 #if defined(INET6) && defined(SCTP_EMBEDDED_V6_SCOPE)
1499 				if (net->ro._l_addr.sa.sa_family == AF_INET6) {
1500 					struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&net->ro._l_addr;
1501 
1502 					(void)sa6_recoverscope(sin6);
1503 				}
1504 #endif				/* INET6 */
1505 			}
1506 			if (net->ro._s_addr)
1507 				net->src_addr_selected = 1;
1508 		}
1509 		if (net->ro._s_addr) {
1510 			mtu = SCTP_GATHER_MTU_FROM_ROUTE(net->ro._s_addr, &net->ro._s_addr.sa, net->ro.ro_nh);
1511 #if defined(INET) || defined(INET6)
1512 			if (net->port) {
1513 				mtu -= sizeof(struct udphdr);
1514 			}
1515 #endif
1516 			if (mtu > next_mtu) {
1517 				net->mtu = next_mtu;
1518 			} else {
1519 				net->mtu = mtu;
1520 			}
1521 		}
1522 	}
1523 	/* restart the timer */
1524 	sctp_timer_start(SCTP_TIMER_TYPE_PATHMTURAISE, inp, stcb, net);
1525 }
1526 
1527 void
sctp_autoclose_timer(struct sctp_inpcb * inp,struct sctp_tcb * stcb)1528 sctp_autoclose_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
1529 {
1530 	struct timeval tn, *tim_touse;
1531 	struct sctp_association *asoc;
1532 	uint32_t ticks_gone_by;
1533 
1534 	(void)SCTP_GETTIME_TIMEVAL(&tn);
1535 	if (stcb->asoc.sctp_autoclose_ticks > 0 &&
1536 	    sctp_is_feature_on(inp, SCTP_PCB_FLAGS_AUTOCLOSE)) {
1537 		/* Auto close is on */
1538 		asoc = &stcb->asoc;
1539 		/* pick the time to use */
1540 		if (asoc->time_last_rcvd.tv_sec >
1541 		    asoc->time_last_sent.tv_sec) {
1542 			tim_touse = &asoc->time_last_rcvd;
1543 		} else {
1544 			tim_touse = &asoc->time_last_sent;
1545 		}
1546 		/* Now has long enough transpired to autoclose? */
1547 		ticks_gone_by = sctp_secs_to_ticks((uint32_t)(tn.tv_sec - tim_touse->tv_sec));
1548 		if (ticks_gone_by >= asoc->sctp_autoclose_ticks) {
1549 			/*
1550 			 * autoclose time has hit, call the output routine,
1551 			 * which should do nothing just to be SURE we don't
1552 			 * have hanging data. We can then safely check the
1553 			 * queues and know that we are clear to send
1554 			 * shutdown
1555 			 */
1556 			sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_AUTOCLOSE_TMR, SCTP_SO_NOT_LOCKED);
1557 			/* Are we clean? */
1558 			if (TAILQ_EMPTY(&asoc->send_queue) &&
1559 			    TAILQ_EMPTY(&asoc->sent_queue)) {
1560 				/*
1561 				 * there is nothing queued to send, so I'm
1562 				 * done...
1563 				 */
1564 				if (SCTP_GET_STATE(stcb) != SCTP_STATE_SHUTDOWN_SENT) {
1565 					/* only send SHUTDOWN 1st time thru */
1566 					struct sctp_nets *net;
1567 
1568 					if ((SCTP_GET_STATE(stcb) == SCTP_STATE_OPEN) ||
1569 					    (SCTP_GET_STATE(stcb) == SCTP_STATE_SHUTDOWN_RECEIVED)) {
1570 						SCTP_STAT_DECR_GAUGE32(sctps_currestab);
1571 					}
1572 					SCTP_SET_STATE(stcb, SCTP_STATE_SHUTDOWN_SENT);
1573 					sctp_stop_timers_for_shutdown(stcb);
1574 					if (stcb->asoc.alternate) {
1575 						net = stcb->asoc.alternate;
1576 					} else {
1577 						net = stcb->asoc.primary_destination;
1578 					}
1579 					sctp_send_shutdown(stcb, net);
1580 					sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWN,
1581 					    stcb->sctp_ep, stcb, net);
1582 					sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
1583 					    stcb->sctp_ep, stcb, NULL);
1584 				}
1585 			}
1586 		} else {
1587 			/*
1588 			 * No auto close at this time, reset t-o to check
1589 			 * later
1590 			 */
1591 			uint32_t tmp;
1592 
1593 			/* fool the timer startup to use the time left */
1594 			tmp = asoc->sctp_autoclose_ticks;
1595 			asoc->sctp_autoclose_ticks -= ticks_gone_by;
1596 			sctp_timer_start(SCTP_TIMER_TYPE_AUTOCLOSE, inp, stcb, NULL);
1597 			/* restore the real tick value */
1598 			asoc->sctp_autoclose_ticks = tmp;
1599 		}
1600 	}
1601 }
1602