xref: /freebsd/sys/netinet/sctp_timer.c (revision f0c8e8118dbcc9251b11154ee7e4680f79901af1)

/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved.
 * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved.
 * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * a) Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *
 * b) Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the distribution.
 *
 * c) Neither the name of Cisco Systems, Inc. nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#define _IP_VHL
#include <netinet/sctp_os.h>
#include <netinet/sctp_pcb.h>
#ifdef INET6
#endif
#include <netinet/sctp_var.h>
#include <netinet/sctp_sysctl.h>
#include <netinet/sctp_timer.h>
#include <netinet/sctputil.h>
#include <netinet/sctp_output.h>
#include <netinet/sctp_header.h>
#include <netinet/sctp_indata.h>
#include <netinet/sctp_asconf.h>
#include <netinet/sctp_input.h>
#include <netinet/sctp.h>
#include <netinet/sctp_uio.h>
#if defined(INET) || defined(INET6)
#include <netinet/udp.h>
#endif

void
sctp_audit_retranmission_queue(struct sctp_association *asoc)
{
	struct sctp_tmit_chunk *chk;

	SCTPDBG(SCTP_DEBUG_TIMER4, "Audit invoked on send queue cnt:%d onqueue:%d\n",
	    asoc->sent_queue_retran_cnt,
	    asoc->sent_queue_cnt);
	asoc->sent_queue_retran_cnt = 0;
	asoc->sent_queue_cnt = 0;
	TAILQ_FOREACH(chk, &asoc->sent_queue, sctp_next) {
		if (chk->sent == SCTP_DATAGRAM_RESEND) {
			sctp_ucount_incr(asoc->sent_queue_retran_cnt);
		}
		asoc->sent_queue_cnt++;
	}
	TAILQ_FOREACH(chk, &asoc->control_send_queue, sctp_next) {
		if (chk->sent == SCTP_DATAGRAM_RESEND) {
			sctp_ucount_incr(asoc->sent_queue_retran_cnt);
		}
	}
	TAILQ_FOREACH(chk, &asoc->asconf_send_queue, sctp_next) {
		if (chk->sent == SCTP_DATAGRAM_RESEND) {
			sctp_ucount_incr(asoc->sent_queue_retran_cnt);
		}
	}
	SCTPDBG(SCTP_DEBUG_TIMER4, "Audit completes retran:%d onqueue:%d\n",
	    asoc->sent_queue_retran_cnt,
	    asoc->sent_queue_cnt);
}

static int
sctp_threshold_management(struct sctp_inpcb *inp, struct sctp_tcb *stcb,
    struct sctp_nets *net, uint16_t threshold)
{
	KASSERT(stcb != NULL, ("stcb is NULL"));
	SCTP_TCB_LOCK_ASSERT(stcb);

	if (net != NULL) {
		net->error_count++;
		SCTPDBG(SCTP_DEBUG_TIMER4, "Error count for %p now %d thresh:%d\n",
		    (void *)net, net->error_count,
		    net->failure_threshold);
		if (net->error_count > net->failure_threshold) {
			/* We had a threshold failure */
			if (net->dest_state & SCTP_ADDR_REACHABLE) {
				net->dest_state &= ~SCTP_ADDR_REACHABLE;
				net->dest_state &= ~SCTP_ADDR_REQ_PRIMARY;
				net->dest_state &= ~SCTP_ADDR_PF;
				sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_DOWN,
				    stcb, 0,
				    (void *)net, SCTP_SO_NOT_LOCKED);
			}
		} else if ((net->pf_threshold < net->failure_threshold) &&
		    (net->error_count > net->pf_threshold)) {
			if ((net->dest_state & SCTP_ADDR_PF) == 0) {
				net->dest_state |= SCTP_ADDR_PF;
				net->last_active = sctp_get_tick_count();
				sctp_send_hb(stcb, net, SCTP_SO_NOT_LOCKED);
				sctp_timer_stop(SCTP_TIMER_TYPE_HEARTBEAT,
				    inp, stcb, net,
				    SCTP_FROM_SCTP_TIMER + SCTP_LOC_1);
				sctp_timer_start(SCTP_TIMER_TYPE_HEARTBEAT, inp, stcb, net);
			}
		}
		if ((net->dest_state & SCTP_ADDR_UNCONFIRMED) == 0) {
			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
				sctp_misc_ints(SCTP_THRESHOLD_INCR,
				    stcb->asoc.overall_error_count,
				    (stcb->asoc.overall_error_count + 1),
				    SCTP_FROM_SCTP_TIMER,
				    __LINE__);
			}
			stcb->asoc.overall_error_count++;
		}
	} else {
		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
			sctp_misc_ints(SCTP_THRESHOLD_INCR,
			    stcb->asoc.overall_error_count,
			    (stcb->asoc.overall_error_count + 1),
			    SCTP_FROM_SCTP_TIMER,
			    __LINE__);
		}
		stcb->asoc.overall_error_count++;
	}
	SCTPDBG(SCTP_DEBUG_TIMER4, "Overall error count for %p now %d thresh:%u state:%x\n",
	    (void *)&stcb->asoc, stcb->asoc.overall_error_count,
	    (uint32_t)threshold,
	    ((net == NULL) ? (uint32_t)0 : (uint32_t)net->dest_state));
	/*
	 * We specifically do not do >= to give the assoc one more change
	 * before we fail it.
	 */
	if (stcb->asoc.overall_error_count > threshold) {
		/* Abort notification sends a ULP notify */
		struct mbuf *op_err;

		op_err = sctp_generate_cause(SCTP_BASE_SYSCTL(sctp_diag_info_code),
		    "Association error counter exceeded");
		inp->last_abort_code = SCTP_FROM_SCTP_TIMER + SCTP_LOC_2;
		sctp_abort_an_association(inp, stcb, op_err, true, SCTP_SO_NOT_LOCKED);
		return (1);
	}
	return (0);
}

/*
 * sctp_find_alternate_net() returns a non-NULL pointer as long as there
 * exists nets, which are not being deleted.
 */
struct sctp_nets *
sctp_find_alternate_net(struct sctp_tcb *stcb,
    struct sctp_nets *net,
    int mode)
{
	/* Find and return an alternate network if possible */
	struct sctp_nets *alt, *mnet, *min_errors_net = NULL, *max_cwnd_net = NULL;
	bool looped;

	/* JRS 5/14/07 - Initialize min_errors to an impossible value. */
	int min_errors = -1;
	uint32_t max_cwnd = 0;

	if (stcb->asoc.numnets == 1) {
		/* No selection can be made. */
		return (TAILQ_FIRST(&stcb->asoc.nets));
	}
	/*
	 * JRS 5/14/07 - If mode is set to 2, use the CMT PF find alternate
	 * net algorithm. This algorithm chooses the active destination (not
	 * in PF state) with the largest cwnd value. If all destinations are
	 * in PF state, unreachable, or unconfirmed, choose the destination
	 * that is in PF state with the lowest error count. In case of a
	 * tie, choose the destination that was most recently active.
	 */
	if (mode == 2) {
		TAILQ_FOREACH(mnet, &stcb->asoc.nets, sctp_next) {
			/*
			 * JRS 5/14/07 - If the destination is unreachable
			 * or unconfirmed, skip it.
			 */
			if (((mnet->dest_state & SCTP_ADDR_REACHABLE) != SCTP_ADDR_REACHABLE) ||
			    (mnet->dest_state & SCTP_ADDR_UNCONFIRMED)) {
				continue;
			}
			/*
			 * JRS 5/14/07 -  If the destination is reachable
			 * but in PF state, compare the error count of the
			 * destination to the minimum error count seen thus
			 * far. Store the destination with the lower error
			 * count.  If the error counts are equal, store the
			 * destination that was most recently active.
			 */
			if (mnet->dest_state & SCTP_ADDR_PF) {
				/*
				 * JRS 5/14/07 - If the destination under
				 * consideration is the current destination,
				 * work as if the error count is one higher.
				 * The actual error count will not be
				 * incremented until later in the t3
				 * handler.
				 */
				if (mnet == net) {
					if (min_errors == -1) {
						min_errors = mnet->error_count + 1;
						min_errors_net = mnet;
					} else if (mnet->error_count + 1 < min_errors) {
						min_errors = mnet->error_count + 1;
						min_errors_net = mnet;
					} else if (mnet->error_count + 1 == min_errors
					    && mnet->last_active > min_errors_net->last_active) {
						min_errors_net = mnet;
						min_errors = mnet->error_count + 1;
					}
					continue;
				} else {
					if (min_errors == -1) {
						min_errors = mnet->error_count;
						min_errors_net = mnet;
					} else if (mnet->error_count < min_errors) {
						min_errors = mnet->error_count;
						min_errors_net = mnet;
					} else if (mnet->error_count == min_errors
					    && mnet->last_active > min_errors_net->last_active) {
						min_errors_net = mnet;
						min_errors = mnet->error_count;
					}
					continue;
				}
			}
			/*
			 * JRS 5/14/07 - If the destination is reachable and
			 * not in PF state, compare the cwnd of the
			 * destination to the highest cwnd seen thus far.
			 * Store the destination with the higher cwnd value.
			 * If the cwnd values are equal, randomly choose one
			 * of the two destinations.
			 */
			if (max_cwnd < mnet->cwnd) {
				max_cwnd_net = mnet;
				max_cwnd = mnet->cwnd;
			} else if (max_cwnd == mnet->cwnd) {
				uint32_t rndval;
				uint8_t this_random;

				if (stcb->asoc.hb_random_idx > 3) {
					rndval = sctp_select_initial_TSN(&stcb->sctp_ep->sctp_ep);
					memcpy(stcb->asoc.hb_random_values, &rndval, sizeof(stcb->asoc.hb_random_values));
					this_random = stcb->asoc.hb_random_values[0];
					stcb->asoc.hb_random_idx++;
					stcb->asoc.hb_ect_randombit = 0;
				} else {
					this_random = stcb->asoc.hb_random_values[stcb->asoc.hb_random_idx];
					stcb->asoc.hb_random_idx++;
					stcb->asoc.hb_ect_randombit = 0;
				}
				if (this_random % 2 == 1) {
					max_cwnd_net = mnet;
					max_cwnd = mnet->cwnd;	/* Useless? */
				}
			}
		}
		if (max_cwnd_net == NULL) {
			if (min_errors_net == NULL) {
				return (net);
			}
			return (min_errors_net);
		} else {
			return (max_cwnd_net);
		}
	}			/* JRS 5/14/07 - If mode is set to 1, use the
				 * CMT policy for choosing an alternate net. */
	else if (mode == 1) {
		TAILQ_FOREACH(mnet, &stcb->asoc.nets, sctp_next) {
			if (((mnet->dest_state & SCTP_ADDR_REACHABLE) != SCTP_ADDR_REACHABLE) ||
			    (mnet->dest_state & SCTP_ADDR_UNCONFIRMED)) {
				/*
				 * will skip ones that are not-reachable or
				 * unconfirmed
				 */
				continue;
			}
			if (max_cwnd < mnet->cwnd) {
				max_cwnd_net = mnet;
				max_cwnd = mnet->cwnd;
			} else if (max_cwnd == mnet->cwnd) {
				uint32_t rndval;
				uint8_t this_random;

				if (stcb->asoc.hb_random_idx > 3) {
					rndval = sctp_select_initial_TSN(&stcb->sctp_ep->sctp_ep);
					memcpy(stcb->asoc.hb_random_values, &rndval,
					    sizeof(stcb->asoc.hb_random_values));
					this_random = stcb->asoc.hb_random_values[0];
					stcb->asoc.hb_random_idx = 0;
					stcb->asoc.hb_ect_randombit = 0;
				} else {
					this_random = stcb->asoc.hb_random_values[stcb->asoc.hb_random_idx];
					stcb->asoc.hb_random_idx++;
					stcb->asoc.hb_ect_randombit = 0;
				}
				if (this_random % 2) {
					max_cwnd_net = mnet;
					max_cwnd = mnet->cwnd;
				}
			}
		}
		if (max_cwnd_net) {
			return (max_cwnd_net);
		}
	}
	/* Look for an alternate net, which is active. */
	if ((net != NULL) && ((net->dest_state & SCTP_ADDR_BEING_DELETED) == 0)) {
		alt = TAILQ_NEXT(net, sctp_next);
	} else {
		alt = TAILQ_FIRST(&stcb->asoc.nets);
	}
	looped = false;
	for (;;) {
		if (alt == NULL) {
			if (!looped) {
				alt = TAILQ_FIRST(&stcb->asoc.nets);
				looped = true;
			}
			/* Definitely out of candidates. */
			if (alt == NULL) {
				break;
			}
		}
		if (alt->ro.ro_nh == NULL) {
			if (alt->ro._s_addr) {
				sctp_free_ifa(alt->ro._s_addr);
				alt->ro._s_addr = NULL;
			}
			alt->src_addr_selected = 0;
		}
		if (((alt->dest_state & SCTP_ADDR_REACHABLE) == SCTP_ADDR_REACHABLE) &&
		    (alt->ro.ro_nh != NULL) &&
		    ((alt->dest_state & SCTP_ADDR_UNCONFIRMED) == 0) &&
		    (alt != net)) {
			/* Found an alternate net, which is reachable. */
			break;
		}
		alt = TAILQ_NEXT(alt, sctp_next);
	}

	if (alt == NULL) {
		/*
		 * In case no active alternate net has been found, look for
		 * an alternate net, which is confirmed.
		 */
		if ((net != NULL) && ((net->dest_state & SCTP_ADDR_BEING_DELETED) == 0)) {
			alt = TAILQ_NEXT(net, sctp_next);
		} else {
			alt = TAILQ_FIRST(&stcb->asoc.nets);
		}
		looped = false;
		for (;;) {
			if (alt == NULL) {
				if (!looped) {
					alt = TAILQ_FIRST(&stcb->asoc.nets);
					looped = true;
				}
				/* Definitely out of candidates. */
				if (alt == NULL) {
					break;
				}
			}
			if (((alt->dest_state & SCTP_ADDR_UNCONFIRMED) == 0) &&
			    (alt != net)) {
				/*
				 * Found an alternate net, which is
				 * confirmed.
				 */
				break;
			}
			alt = TAILQ_NEXT(alt, sctp_next);
		}
	}
	if (alt == NULL) {
		/*
		 * In case no confirmed alternate net has been found, just
		 * return net, if it is not being deleted. In the other case
		 * just return the first net.
		 */
		if ((net != NULL) && ((net->dest_state & SCTP_ADDR_BEING_DELETED) == 0)) {
			alt = net;
		}
		if (alt == NULL) {
			alt = TAILQ_FIRST(&stcb->asoc.nets);
		}
	}
	return (alt);
}

static void
sctp_backoff_on_timeout(struct sctp_tcb *stcb,
    struct sctp_nets *net,
    int win_probe,
    int num_marked, int num_abandoned)
{
	if (net->RTO == 0) {
		if (net->RTO_measured) {
			net->RTO = stcb->asoc.minrto;
		} else {
			net->RTO = stcb->asoc.initial_rto;
		}
	}
	net->RTO <<= 1;
	if (net->RTO > stcb->asoc.maxrto) {
		net->RTO = stcb->asoc.maxrto;
	}
	if ((win_probe == 0) && (num_marked || num_abandoned)) {
		/* We don't apply penalty to window probe scenarios */
		/* JRS - Use the congestion control given in the CC module */
		stcb->asoc.cc_functions.sctp_cwnd_update_after_timeout(stcb, net);
	}
}

#ifndef INVARIANTS
static void
sctp_recover_sent_list(struct sctp_tcb *stcb)
{
	struct sctp_tmit_chunk *chk, *nchk;
	struct sctp_association *asoc;

	asoc = &stcb->asoc;
	TAILQ_FOREACH_SAFE(chk, &asoc->sent_queue, sctp_next, nchk) {
		if (SCTP_TSN_GE(asoc->last_acked_seq, chk->rec.data.tsn)) {
			SCTP_PRINTF("Found chk:%p tsn:%x <= last_acked_seq:%x\n",
			    (void *)chk, chk->rec.data.tsn, asoc->last_acked_seq);
			if (chk->sent != SCTP_DATAGRAM_NR_ACKED) {
				if (asoc->strmout[chk->rec.data.sid].chunks_on_queues > 0) {
					asoc->strmout[chk->rec.data.sid].chunks_on_queues--;
				}
			}
			if ((asoc->strmout[chk->rec.data.sid].chunks_on_queues == 0) &&
			    (asoc->strmout[chk->rec.data.sid].state == SCTP_STREAM_RESET_PENDING) &&
			    TAILQ_EMPTY(&asoc->strmout[chk->rec.data.sid].outqueue)) {
				asoc->trigger_reset = 1;
			}
			TAILQ_REMOVE(&asoc->sent_queue, chk, sctp_next);
			if (PR_SCTP_ENABLED(chk->flags)) {
				if (asoc->pr_sctp_cnt != 0)
					asoc->pr_sctp_cnt--;
			}
			if (chk->data) {
				/* sa_ignore NO_NULL_CHK */
				sctp_free_bufspace(stcb, asoc, chk, 1);
				sctp_m_freem(chk->data);
				chk->data = NULL;
				if (asoc->prsctp_supported && PR_SCTP_BUF_ENABLED(chk->flags)) {
					asoc->sent_queue_cnt_removeable--;
				}
			}
			asoc->sent_queue_cnt--;
			sctp_free_a_chunk(stcb, chk, SCTP_SO_NOT_LOCKED);
		}
	}
	SCTP_PRINTF("after recover order is as follows\n");
	TAILQ_FOREACH(chk, &asoc->sent_queue, sctp_next) {
		SCTP_PRINTF("chk:%p TSN:%x\n", (void *)chk, chk->rec.data.tsn);
	}
}
#endif

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)
{

	/*
	 * Mark all chunks (well not all) that were sent to *net for
	 * retransmission. Move them to alt for there destination as well...
	 * We only mark chunks that have been outstanding long enough to
	 * have received feed-back.
	 */
	struct sctp_tmit_chunk *chk, *nchk;
	struct sctp_nets *lnets;
	struct timeval now, min_wait, tv;
	int cur_rto;
	int cnt_abandoned;
	int audit_tf, num_mk, fir;
	unsigned int cnt_mk;
	uint32_t orig_flight, orig_tf;
	uint32_t tsnlast, tsnfirst;
#ifndef INVARIANTS
	int recovery_cnt = 0;
#endif

	/* none in flight now */
	audit_tf = 0;
	fir = 0;
	/*
	 * figure out how long a data chunk must be pending before we can
	 * mark it ..
	 */
	(void)SCTP_GETTIME_TIMEVAL(&now);
	/* get cur rto in micro-seconds */
	cur_rto = (net->lastsa >> SCTP_RTT_SHIFT) + net->lastsv;
	cur_rto *= 1000;
	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
		sctp_log_fr(cur_rto,
		    stcb->asoc.peers_rwnd,
		    window_probe,
		    SCTP_FR_T3_MARK_TIME);
		sctp_log_fr(net->flight_size, 0, 0, SCTP_FR_CWND_REPORT);
		sctp_log_fr(net->flight_size, net->cwnd, stcb->asoc.total_flight, SCTP_FR_CWND_REPORT);
	}
	tv.tv_sec = cur_rto / 1000000;
	tv.tv_usec = cur_rto % 1000000;
	min_wait = now;
	timevalsub(&min_wait, &tv);
	if (min_wait.tv_sec < 0 || min_wait.tv_usec < 0) {
		/*
		 * if we hit here, we don't have enough seconds on the clock
		 * to account for the RTO. We just let the lower seconds be
		 * the bounds and don't worry about it. This may mean we
		 * will mark a lot more than we should.
		 */
		min_wait.tv_sec = min_wait.tv_usec = 0;
	}
	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
		sctp_log_fr(cur_rto, (uint32_t)now.tv_sec, now.tv_usec, SCTP_FR_T3_MARK_TIME);
		sctp_log_fr(0, (uint32_t)min_wait.tv_sec, min_wait.tv_usec, SCTP_FR_T3_MARK_TIME);
	}
	/*
	 * Our rwnd will be incorrect here since we are not adding back the
	 * cnt * mbuf but we will fix that down below.
	 */
	orig_flight = net->flight_size;
	orig_tf = stcb->asoc.total_flight;

	net->fast_retran_ip = 0;
	/* Now on to each chunk */
	cnt_abandoned = 0;
	num_mk = cnt_mk = 0;
	tsnfirst = tsnlast = 0;
#ifndef INVARIANTS
start_again:
#endif
	TAILQ_FOREACH_SAFE(chk, &stcb->asoc.sent_queue, sctp_next, nchk) {
		if (SCTP_TSN_GE(stcb->asoc.last_acked_seq, chk->rec.data.tsn)) {
			/* Strange case our list got out of order? */
			SCTP_PRINTF("Our list is out of order? last_acked:%x chk:%x\n",
			    (unsigned int)stcb->asoc.last_acked_seq, (unsigned int)chk->rec.data.tsn);
#ifdef INVARIANTS
			panic("last acked >= chk on sent-Q");
#else
			recovery_cnt++;
			SCTP_PRINTF("Recover attempts a restart cnt:%d\n", recovery_cnt);
			sctp_recover_sent_list(stcb);
			if (recovery_cnt < 10) {
				goto start_again;
			} else {
				SCTP_PRINTF("Recovery fails %d times??\n", recovery_cnt);
			}
#endif
		}
		if ((chk->whoTo == net) && (chk->sent < SCTP_DATAGRAM_ACKED)) {
			/*
			 * found one to mark: If it is less than
			 * DATAGRAM_ACKED it MUST not be a skipped or marked
			 * TSN but instead one that is either already set
			 * for retransmission OR one that needs
			 * retransmission.
			 */

			/* validate its been outstanding long enough */
			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
				sctp_log_fr(chk->rec.data.tsn,
				    (uint32_t)chk->sent_rcv_time.tv_sec,
				    chk->sent_rcv_time.tv_usec,
				    SCTP_FR_T3_MARK_TIME);
			}
			if ((chk->sent_rcv_time.tv_sec > min_wait.tv_sec) && (window_probe == 0)) {
				/*
				 * we have reached a chunk that was sent
				 * some seconds past our min.. forget it we
				 * will find no more to send.
				 */
				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
					sctp_log_fr(0,
					    (uint32_t)chk->sent_rcv_time.tv_sec,
					    chk->sent_rcv_time.tv_usec,
					    SCTP_FR_T3_STOPPED);
				}
				continue;
			} else if ((chk->sent_rcv_time.tv_sec == min_wait.tv_sec) &&
			    (window_probe == 0)) {
				/*
				 * we must look at the micro seconds to
				 * know.
				 */
				if (chk->sent_rcv_time.tv_usec >= min_wait.tv_usec) {
					/*
					 * ok it was sent after our boundary
					 * time.
					 */
					continue;
				}
			}
			if (stcb->asoc.prsctp_supported && PR_SCTP_TTL_ENABLED(chk->flags)) {
				/* Is it expired? */
				if (timevalcmp(&now, &chk->rec.data.timetodrop, >)) {
					/* Yes so drop it */
					if (chk->data) {
						(void)sctp_release_pr_sctp_chunk(stcb,
						    chk,
						    1,
						    SCTP_SO_NOT_LOCKED);
						cnt_abandoned++;
					}
					continue;
				}
			}
			if (stcb->asoc.prsctp_supported && PR_SCTP_RTX_ENABLED(chk->flags)) {
				/* Has it been retransmitted tv_sec times? */
				if (chk->snd_count > chk->rec.data.timetodrop.tv_sec) {
					if (chk->data) {
						(void)sctp_release_pr_sctp_chunk(stcb,
						    chk,
						    1,
						    SCTP_SO_NOT_LOCKED);
						cnt_abandoned++;
					}
					continue;
				}
			}
			if (chk->sent < SCTP_DATAGRAM_RESEND) {
				sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
				num_mk++;
				if (fir == 0) {
					fir = 1;
					tsnfirst = chk->rec.data.tsn;
				}
				tsnlast = chk->rec.data.tsn;
				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
					sctp_log_fr(chk->rec.data.tsn, chk->snd_count,
					    0, SCTP_FR_T3_MARKED);
				}

				if (chk->rec.data.chunk_was_revoked) {
					/* deflate the cwnd */
					chk->whoTo->cwnd -= chk->book_size;
					chk->rec.data.chunk_was_revoked = 0;
				}
				net->marked_retrans++;
				stcb->asoc.marked_retrans++;
				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FLIGHT_LOGGING_ENABLE) {
					sctp_misc_ints(SCTP_FLIGHT_LOG_DOWN_RSND_TO,
					    chk->whoTo->flight_size,
					    chk->book_size,
					    (uint32_t)(uintptr_t)chk->whoTo,
					    chk->rec.data.tsn);
				}
				sctp_flight_size_decrease(chk);
				sctp_total_flight_decrease(stcb, chk);
				stcb->asoc.peers_rwnd += chk->send_size;
				stcb->asoc.peers_rwnd += SCTP_BASE_SYSCTL(sctp_peer_chunk_oh);
			}
			chk->sent = SCTP_DATAGRAM_RESEND;
			chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
			SCTP_STAT_INCR(sctps_markedretrans);

			/* reset the TSN for striking and other FR stuff */
			chk->rec.data.doing_fast_retransmit = 0;
			/* Clear any time so NO RTT is being done */

			if (chk->do_rtt) {
				if (chk->whoTo->rto_needed == 0) {
					chk->whoTo->rto_needed = 1;
				}
			}
			chk->do_rtt = 0;
			if (alt != net) {
				sctp_free_remote_addr(chk->whoTo);
				chk->no_fr_allowed = 1;
				chk->whoTo = alt;
				atomic_add_int(&alt->ref_count, 1);
			} else {
				chk->no_fr_allowed = 0;
				if (TAILQ_EMPTY(&stcb->asoc.send_queue)) {
					chk->rec.data.fast_retran_tsn = stcb->asoc.sending_seq;
				} else {
					chk->rec.data.fast_retran_tsn = (TAILQ_FIRST(&stcb->asoc.send_queue))->rec.data.tsn;
				}
			}
			/*
			 * CMT: Do not allow FRs on retransmitted TSNs.
			 */
			if (stcb->asoc.sctp_cmt_on_off > 0) {
				chk->no_fr_allowed = 1;
			}
#ifdef THIS_SHOULD_NOT_BE_DONE
		} else if (chk->sent == SCTP_DATAGRAM_ACKED) {
			/* remember highest acked one */
			could_be_sent = chk;
#endif
		}
		if (chk->sent == SCTP_DATAGRAM_RESEND) {
			cnt_mk++;
		}
	}
	if ((orig_flight - net->flight_size) != (orig_tf - stcb->asoc.total_flight)) {
		/* we did not subtract the same things? */
		audit_tf = 1;
	}

	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
		sctp_log_fr(tsnfirst, tsnlast, num_mk, SCTP_FR_T3_TIMEOUT);
	}
#ifdef SCTP_DEBUG
	if (num_mk) {
		SCTPDBG(SCTP_DEBUG_TIMER1, "LAST TSN marked was %x\n",
		    tsnlast);
		SCTPDBG(SCTP_DEBUG_TIMER1, "Num marked for retransmission was %d peer-rwd:%u\n",
		    num_mk,
		    stcb->asoc.peers_rwnd);
	}
#endif
	*num_marked = num_mk;
	*num_abandoned = cnt_abandoned;
	/*
	 * Now check for a ECN Echo that may be stranded And include the
	 * cnt_mk'd to have all resends in the control queue.
	 */
	TAILQ_FOREACH(chk, &stcb->asoc.control_send_queue, sctp_next) {
		if (chk->sent == SCTP_DATAGRAM_RESEND) {
			cnt_mk++;
		}
		if ((chk->whoTo == net) &&
		    (chk->rec.chunk_id.id == SCTP_ECN_ECHO)) {
			sctp_free_remote_addr(chk->whoTo);
			chk->whoTo = alt;
			if (chk->sent != SCTP_DATAGRAM_RESEND) {
				chk->sent = SCTP_DATAGRAM_RESEND;
				chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
				sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
				cnt_mk++;
			}
			atomic_add_int(&alt->ref_count, 1);
		}
	}
#ifdef THIS_SHOULD_NOT_BE_DONE
	if ((stcb->asoc.sent_queue_retran_cnt == 0) && (could_be_sent)) {
		/* fix it so we retransmit the highest acked anyway */
		sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
		cnt_mk++;
		could_be_sent->sent = SCTP_DATAGRAM_RESEND;
	}
#endif
	if (stcb->asoc.sent_queue_retran_cnt != cnt_mk) {
#ifdef INVARIANTS
		SCTP_PRINTF("Local Audit says there are %d for retran asoc cnt:%d we marked:%d this time\n",
		    cnt_mk, stcb->asoc.sent_queue_retran_cnt, num_mk);
#endif
#ifndef SCTP_AUDITING_ENABLED
		stcb->asoc.sent_queue_retran_cnt = cnt_mk;
#endif
	}
	if (audit_tf) {
		SCTPDBG(SCTP_DEBUG_TIMER4,
		    "Audit total flight due to negative value net:%p\n",
		    (void *)net);
		stcb->asoc.total_flight = 0;
		stcb->asoc.total_flight_count = 0;
		/* Clear all networks flight size */
		TAILQ_FOREACH(lnets, &stcb->asoc.nets, sctp_next) {
			lnets->flight_size = 0;
			SCTPDBG(SCTP_DEBUG_TIMER4,
			    "Net:%p c-f cwnd:%d ssthresh:%d\n",
			    (void *)lnets, lnets->cwnd, lnets->ssthresh);
		}
		TAILQ_FOREACH(chk, &stcb->asoc.sent_queue, sctp_next) {
			if (chk->sent < SCTP_DATAGRAM_RESEND) {
				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FLIGHT_LOGGING_ENABLE) {
					sctp_misc_ints(SCTP_FLIGHT_LOG_UP,
					    chk->whoTo->flight_size,
					    chk->book_size,
					    (uint32_t)(uintptr_t)chk->whoTo,
					    chk->rec.data.tsn);
				}

				sctp_flight_size_increase(chk);
				sctp_total_flight_increase(stcb, chk);
			}
		}
	}
	/* We return 1 if we only have a window probe outstanding */
	return (0);
}

int
sctp_t3rxt_timer(struct sctp_inpcb *inp,
    struct sctp_tcb *stcb,
    struct sctp_nets *net)
{
	struct sctp_nets *alt;
	int win_probe, num_mk, num_abandoned;

	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
		sctp_log_fr(0, 0, 0, SCTP_FR_T3_TIMEOUT);
	}
	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
		struct sctp_nets *lnet;

		TAILQ_FOREACH(lnet, &stcb->asoc.nets, sctp_next) {
			if (net == lnet) {
				sctp_log_cwnd(stcb, lnet, 1, SCTP_CWND_LOG_FROM_T3);
			} else {
				sctp_log_cwnd(stcb, lnet, 0, SCTP_CWND_LOG_FROM_T3);
			}
		}
	}
	/* Find an alternate and mark those for retransmission */
	if ((stcb->asoc.peers_rwnd == 0) &&
	    (stcb->asoc.total_flight < net->mtu)) {
		SCTP_STAT_INCR(sctps_timowindowprobe);
		win_probe = 1;
	} else {
		win_probe = 0;
	}

	if (win_probe == 0) {
		/* We don't do normal threshold management on window probes */
		if (sctp_threshold_management(inp, stcb, net,
		    stcb->asoc.max_send_times)) {
			/* Association was destroyed */
			return (1);
		} else {
			if (net != stcb->asoc.primary_destination) {
				/* send a immediate HB if our RTO is stale */
				struct timeval now;
				uint32_t ms_goneby;

				(void)SCTP_GETTIME_TIMEVAL(&now);
				if (net->last_sent_time.tv_sec) {
					ms_goneby = (uint32_t)(now.tv_sec - net->last_sent_time.tv_sec) * 1000;
				} else {
					ms_goneby = 0;
				}
				if ((net->dest_state & SCTP_ADDR_PF) == 0) {
					if ((ms_goneby > net->RTO) || (net->RTO == 0)) {
						/*
						 * no recent feed back in an
						 * RTO or more, request a
						 * RTT update
						 */
						sctp_send_hb(stcb, net, SCTP_SO_NOT_LOCKED);
					}
				}
			}
		}
	} else {
		/*
		 * For a window probe we don't penalize the net's but only
		 * the association. This may fail it if SACKs are not coming
		 * back. If sack's are coming with rwnd locked at 0, we will
		 * continue to hold things waiting for rwnd to raise
		 */
		if (sctp_threshold_management(inp, stcb, NULL,
		    stcb->asoc.max_send_times)) {
			/* Association was destroyed */
			return (1);
		}
	}
	if (stcb->asoc.sctp_cmt_on_off > 0) {
		if (net->pf_threshold < net->failure_threshold) {
			alt = sctp_find_alternate_net(stcb, net, 2);
		} else {
			/*
			 * CMT: Using RTX_SSTHRESH policy for CMT. If CMT is
			 * being used, then pick dest with largest ssthresh
			 * for any retransmission.
			 */
			alt = sctp_find_alternate_net(stcb, net, 1);
			/*
			 * CUCv2: If a different dest is picked for the
			 * retransmission, then new (rtx-)pseudo_cumack
			 * needs to be tracked for orig dest. Let CUCv2
			 * track new (rtx-) pseudo-cumack always.
			 */
			net->find_pseudo_cumack = 1;
			net->find_rtx_pseudo_cumack = 1;
		}
	} else {
		alt = sctp_find_alternate_net(stcb, net, 0);
	}

	num_mk = 0;
	num_abandoned = 0;
	(void)sctp_mark_all_for_resend(stcb, net, alt, win_probe,
	    &num_mk, &num_abandoned);
	/* FR Loss recovery just ended with the T3. */
	stcb->asoc.fast_retran_loss_recovery = 0;

	/* CMT FR loss recovery ended with the T3 */
	net->fast_retran_loss_recovery = 0;
	if ((stcb->asoc.cc_functions.sctp_cwnd_new_transmission_begins) &&
	    (net->flight_size == 0)) {
		(*stcb->asoc.cc_functions.sctp_cwnd_new_transmission_begins) (stcb, net);
	}

	/*
	 * setup the sat loss recovery that prevents satellite cwnd advance.
	 */
	stcb->asoc.sat_t3_loss_recovery = 1;
	stcb->asoc.sat_t3_recovery_tsn = stcb->asoc.sending_seq;

	/* Backoff the timer and cwnd */
	sctp_backoff_on_timeout(stcb, net, win_probe, num_mk, num_abandoned);
	if (((net->dest_state & SCTP_ADDR_REACHABLE) == 0) ||
	    (net->dest_state & SCTP_ADDR_PF)) {
		/* Move all pending over too */
		sctp_move_chunks_from_net(stcb, net);

		/*
		 * Get the address that failed, to force a new src address
		 * selection and a route allocation.
		 */
		if (net->ro._s_addr != NULL) {
			sctp_free_ifa(net->ro._s_addr);
			net->ro._s_addr = NULL;
		}
		net->src_addr_selected = 0;

		/* Force a route allocation too */
		RO_NHFREE(&net->ro);

		/* Was it our primary? */
		if ((stcb->asoc.primary_destination == net) && (alt != net)) {
			/*
			 * Yes, note it as such and find an alternate note:
			 * this means HB code must use this to resent the
			 * primary if it goes active AND if someone does a
			 * change-primary then this flag must be cleared
			 * from any net structures.
			 */
			if (stcb->asoc.alternate != NULL) {
				sctp_free_remote_addr(stcb->asoc.alternate);
			}
			stcb->asoc.alternate = alt;
			atomic_add_int(&stcb->asoc.alternate->ref_count, 1);
		}
	}
	/*
	 * Special case for cookie-echo'ed case, we don't do output but must
	 * await the COOKIE-ACK before retransmission
	 */
	if (SCTP_GET_STATE(stcb) == SCTP_STATE_COOKIE_ECHOED) {
		/*
		 * Here we just reset the timer and start again since we
		 * have not established the asoc
		 */
		sctp_timer_start(SCTP_TIMER_TYPE_SEND, inp, stcb, net);
		return (0);
	}
	if (stcb->asoc.prsctp_supported) {
		struct sctp_tmit_chunk *lchk;

		lchk = sctp_try_advance_peer_ack_point(stcb, &stcb->asoc);
		/* C3. See if we need to send a Fwd-TSN */
		if (SCTP_TSN_GT(stcb->asoc.advanced_peer_ack_point, stcb->asoc.last_acked_seq)) {
			send_forward_tsn(stcb, &stcb->asoc);
			for (; lchk != NULL; lchk = TAILQ_NEXT(lchk, sctp_next)) {
				if (lchk->whoTo != NULL) {
					break;
				}
			}
			if (lchk != NULL) {
				/* Assure a timer is up */
				sctp_timer_start(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep, stcb, lchk->whoTo);
			}
		}
	}
	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
		sctp_log_cwnd(stcb, net, net->cwnd, SCTP_CWND_LOG_FROM_RTX);
	}
	return (0);
}

int
sctp_t1init_timer(struct sctp_inpcb *inp,
    struct sctp_tcb *stcb,
    struct sctp_nets *net)
{
	/* bump the thresholds */
	if (stcb->asoc.delayed_connection) {
		/*
		 * special hook for delayed connection. The library did NOT
		 * complete the rest of its sends.
		 */
		stcb->asoc.delayed_connection = 0;
		sctp_send_initiate(inp, stcb, SCTP_SO_NOT_LOCKED);
		return (0);
	}
	if (SCTP_GET_STATE(stcb) != SCTP_STATE_COOKIE_WAIT) {
		return (0);
	}
	if (sctp_threshold_management(inp, stcb, net,
	    stcb->asoc.max_init_times)) {
		/* Association was destroyed */
		return (1);
	}
	stcb->asoc.dropped_special_cnt = 0;
	sctp_backoff_on_timeout(stcb, stcb->asoc.primary_destination, 1, 0, 0);
	if (stcb->asoc.initial_init_rto_max < net->RTO) {
		net->RTO = stcb->asoc.initial_init_rto_max;
	}
	if (stcb->asoc.numnets > 1) {
		/* If we have more than one addr use it */
		struct sctp_nets *alt;

		alt = sctp_find_alternate_net(stcb, stcb->asoc.primary_destination, 0);
		if (alt != stcb->asoc.primary_destination) {
			sctp_move_chunks_from_net(stcb, stcb->asoc.primary_destination);
			stcb->asoc.primary_destination = alt;
		}
	}
	/* Send out a new init */
	sctp_send_initiate(inp, stcb, SCTP_SO_NOT_LOCKED);
	return (0);
}

/*
 * For cookie and asconf we actually need to find and mark for resend, then
 * increment the resend counter (after all the threshold management stuff of
 * course).
 */
int
sctp_cookie_timer(struct sctp_inpcb *inp,
    struct sctp_tcb *stcb,
    struct sctp_nets *net SCTP_UNUSED)
{
	struct sctp_nets *alt;
	struct sctp_tmit_chunk *cookie;

	/* first before all else we must find the cookie */
	TAILQ_FOREACH(cookie, &stcb->asoc.control_send_queue, sctp_next) {
		if (cookie->rec.chunk_id.id == SCTP_COOKIE_ECHO) {
			break;
		}
	}
	if (cookie == NULL) {
		if (SCTP_GET_STATE(stcb) == SCTP_STATE_COOKIE_ECHOED) {
			/* FOOBAR! */
			struct mbuf *op_err;

			op_err = sctp_generate_cause(SCTP_BASE_SYSCTL(sctp_diag_info_code),
			    "Cookie timer expired, but no cookie");
			inp->last_abort_code = SCTP_FROM_SCTP_TIMER + SCTP_LOC_3;
			sctp_abort_an_association(inp, stcb, op_err, false, SCTP_SO_NOT_LOCKED);
		} else {
#ifdef INVARIANTS
			panic("Cookie timer expires in wrong state?");
#else
			SCTP_PRINTF("Strange in state %d not cookie-echoed yet c-e timer expires?\n", SCTP_GET_STATE(stcb));
			return (0);
#endif
		}
		return (0);
	}
	/* Ok we found the cookie, threshold management next */
	if (sctp_threshold_management(inp, stcb, cookie->whoTo,
	    stcb->asoc.max_init_times)) {
		/* Assoc is over */
		return (1);
	}
	/*
	 * Cleared threshold management, now lets backoff the address and
	 * select an alternate
	 */
	stcb->asoc.dropped_special_cnt = 0;
	sctp_backoff_on_timeout(stcb, cookie->whoTo, 1, 0, 0);
	alt = sctp_find_alternate_net(stcb, cookie->whoTo, 0);
	if (alt != cookie->whoTo) {
		sctp_free_remote_addr(cookie->whoTo);
		cookie->whoTo = alt;
		atomic_add_int(&alt->ref_count, 1);
	}
	/* Now mark the retran info */
	if (cookie->sent != SCTP_DATAGRAM_RESEND) {
		sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
	}
	cookie->sent = SCTP_DATAGRAM_RESEND;
	cookie->flags |= CHUNK_FLAGS_FRAGMENT_OK;
	/*
	 * Now call the output routine to kick out the cookie again, Note we
	 * don't mark any chunks for retran so that FR will need to kick in
	 * to move these (or a send timer).
	 */
	return (0);
}

int
sctp_strreset_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
{
	struct sctp_nets *alt, *net;
	struct sctp_tmit_chunk *strrst = NULL, *chk = NULL;

	if (stcb->asoc.stream_reset_outstanding == 0) {
		return (0);
	}
	/* find the existing STRRESET, we use the seq number we sent out on */
	(void)sctp_find_stream_reset(stcb, stcb->asoc.str_reset_seq_out, &strrst);
	if (strrst == NULL) {
		return (0);
	}
	net = strrst->whoTo;
	/* do threshold management */
	if (sctp_threshold_management(inp, stcb, net, stcb->asoc.max_send_times)) {
		/* Assoc is over */
		return (1);
	}
	/*
	 * Cleared threshold management, now lets backoff the address and
	 * select an alternate
	 */
	sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
	alt = sctp_find_alternate_net(stcb, net, 0);
	strrst->whoTo = alt;
	atomic_add_int(&alt->ref_count, 1);

	/* See if a ECN Echo is also stranded */
	TAILQ_FOREACH(chk, &stcb->asoc.control_send_queue, sctp_next) {
		if ((chk->whoTo == net) &&
		    (chk->rec.chunk_id.id == SCTP_ECN_ECHO)) {
			sctp_free_remote_addr(chk->whoTo);
			if (chk->sent != SCTP_DATAGRAM_RESEND) {
				chk->sent = SCTP_DATAGRAM_RESEND;
				chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
				sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
			}
			chk->whoTo = alt;
			atomic_add_int(&alt->ref_count, 1);
		}
	}
	if ((net->dest_state & SCTP_ADDR_REACHABLE) == 0) {
		/*
		 * If the address went un-reachable, we need to move to
		 * alternates for ALL chk's in queue
		 */
		sctp_move_chunks_from_net(stcb, net);
	}
	sctp_free_remote_addr(net);

	/* mark the retran info */
	if (strrst->sent != SCTP_DATAGRAM_RESEND)
		sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
	strrst->sent = SCTP_DATAGRAM_RESEND;
	strrst->flags |= CHUNK_FLAGS_FRAGMENT_OK;

	/* restart the timer */
	sctp_timer_start(SCTP_TIMER_TYPE_STRRESET, inp, stcb, alt);
	return (0);
}

int
sctp_asconf_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb,
    struct sctp_nets *net)
{
	struct sctp_nets *alt;
	struct sctp_tmit_chunk *asconf, *chk;

	/* is this a first send, or a retransmission? */
	if (TAILQ_EMPTY(&stcb->asoc.asconf_send_queue)) {
		/* compose a new ASCONF chunk and send it */
		sctp_send_asconf(stcb, net, SCTP_ADDR_NOT_LOCKED);
	} else {
		/*
		 * Retransmission of the existing ASCONF is needed
		 */

		/* find the existing ASCONF */
		asconf = TAILQ_FIRST(&stcb->asoc.asconf_send_queue);
		if (asconf == NULL) {
			return (0);
		}
		net = asconf->whoTo;
		/* do threshold management */
		if (sctp_threshold_management(inp, stcb, net,
		    stcb->asoc.max_send_times)) {
			/* Assoc is over */
			return (1);
		}
		if (asconf->snd_count > stcb->asoc.max_send_times) {
			/*
			 * Something is rotten: our peer is not responding
			 * to ASCONFs but apparently is to other chunks.
			 * i.e. it is not properly handling the chunk type
			 * upper bits. Mark this peer as ASCONF incapable
			 * and cleanup.
			 */
			SCTPDBG(SCTP_DEBUG_TIMER1, "asconf_timer: Peer has not responded to our repeated ASCONFs\n");
			sctp_asconf_cleanup(stcb);
			return (0);
		}
		/*
		 * cleared threshold management, so now backoff the net and
		 * select an alternate
		 */
		sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
		alt = sctp_find_alternate_net(stcb, net, 0);
		if (asconf->whoTo != alt) {
			asconf->whoTo = alt;
			atomic_add_int(&alt->ref_count, 1);
		}

		/* See if an ECN Echo is also stranded */
		TAILQ_FOREACH(chk, &stcb->asoc.control_send_queue, sctp_next) {
			if ((chk->whoTo == net) &&
			    (chk->rec.chunk_id.id == SCTP_ECN_ECHO)) {
				sctp_free_remote_addr(chk->whoTo);
				chk->whoTo = alt;
				if (chk->sent != SCTP_DATAGRAM_RESEND) {
					chk->sent = SCTP_DATAGRAM_RESEND;
					chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
					sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
				}
				atomic_add_int(&alt->ref_count, 1);
			}
		}
		TAILQ_FOREACH(chk, &stcb->asoc.asconf_send_queue, sctp_next) {
			if (chk->whoTo != alt) {
				sctp_free_remote_addr(chk->whoTo);
				chk->whoTo = alt;
				atomic_add_int(&alt->ref_count, 1);
			}
			if (asconf->sent != SCTP_DATAGRAM_RESEND && chk->sent != SCTP_DATAGRAM_UNSENT)
				sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
			chk->sent = SCTP_DATAGRAM_RESEND;
			chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
		}
		if ((net->dest_state & SCTP_ADDR_REACHABLE) == 0) {
			/*
			 * If the address went un-reachable, we need to move
			 * to the alternate for ALL chunks in queue
			 */
			sctp_move_chunks_from_net(stcb, net);
		}
		sctp_free_remote_addr(net);

		/* mark the retran info */
		if (asconf->sent != SCTP_DATAGRAM_RESEND)
			sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
		asconf->sent = SCTP_DATAGRAM_RESEND;
		asconf->flags |= CHUNK_FLAGS_FRAGMENT_OK;

		/* send another ASCONF if any and we can do */
		sctp_send_asconf(stcb, alt, SCTP_ADDR_NOT_LOCKED);
	}
	return (0);
}

/* Mobility adaptation */
void
sctp_delete_prim_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
{
	if (stcb->asoc.deleted_primary == NULL) {
		SCTPDBG(SCTP_DEBUG_ASCONF1, "delete_prim_timer: deleted_primary is not stored...\n");
		sctp_mobility_feature_off(inp, SCTP_MOBILITY_PRIM_DELETED);
		return;
	}
	SCTPDBG(SCTP_DEBUG_ASCONF1, "delete_prim_timer: finished to keep deleted primary ");
	SCTPDBG_ADDR(SCTP_DEBUG_ASCONF1, &stcb->asoc.deleted_primary->ro._l_addr.sa);
	sctp_free_remote_addr(stcb->asoc.deleted_primary);
	stcb->asoc.deleted_primary = NULL;
	sctp_mobility_feature_off(inp, SCTP_MOBILITY_PRIM_DELETED);
	return;
}

/*
 * For the shutdown and shutdown-ack, we do not keep one around on the
 * control queue. This means we must generate a new one and call the general
 * chunk output routine, AFTER having done threshold management.
 * It is assumed that net is non-NULL.
 */
int
sctp_shutdown_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb,
    struct sctp_nets *net)
{
	struct sctp_nets *alt;

	/* first threshold management */
	if (sctp_threshold_management(inp, stcb, net, stcb->asoc.max_send_times)) {
		/* Assoc is over */
		return (1);
	}
	sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
	/* second select an alternative */
	alt = sctp_find_alternate_net(stcb, net, 0);

	/* third generate a shutdown into the queue for out net */
	sctp_send_shutdown(stcb, alt);

	/* fourth restart timer */
	sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWN, inp, stcb, alt);
	return (0);
}

int
sctp_shutdownack_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb,
    struct sctp_nets *net)
{
	struct sctp_nets *alt;

	/* first threshold management */
	if (sctp_threshold_management(inp, stcb, net, stcb->asoc.max_send_times)) {
		/* Assoc is over */
		return (1);
	}
	sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
	/* second select an alternative */
	alt = sctp_find_alternate_net(stcb, net, 0);

	/* third generate a shutdown into the queue for out net */
	sctp_send_shutdown_ack(stcb, alt);

	/* fourth restart timer */
	sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNACK, inp, stcb, alt);
	return (0);
}

static void
sctp_audit_stream_queues_for_size(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
{
	struct sctp_stream_queue_pending *sp;
	unsigned int i, chks_in_queue = 0;
	int being_filled = 0;

	KASSERT(inp != NULL, ("inp is NULL"));
	KASSERT(stcb != NULL, ("stcb is NULL"));
	SCTP_TCB_LOCK_ASSERT(stcb);
	KASSERT(TAILQ_EMPTY(&stcb->asoc.send_queue), ("send_queue not empty"));
	KASSERT(TAILQ_EMPTY(&stcb->asoc.sent_queue), ("sent_queue not empty"));

	if (stcb->asoc.sent_queue_retran_cnt) {
		SCTP_PRINTF("Hmm, sent_queue_retran_cnt is non-zero %d\n",
		    stcb->asoc.sent_queue_retran_cnt);
		stcb->asoc.sent_queue_retran_cnt = 0;
	}
	if (stcb->asoc.ss_functions.sctp_ss_is_empty(stcb, &stcb->asoc)) {
		/* No stream scheduler information, initialize scheduler */
		stcb->asoc.ss_functions.sctp_ss_init(stcb, &stcb->asoc);
		if (!stcb->asoc.ss_functions.sctp_ss_is_empty(stcb, &stcb->asoc)) {
			/* yep, we lost a stream or two */
			SCTP_PRINTF("Found additional streams NOT managed by scheduler, corrected\n");
		} else {
			/* no streams lost */
			stcb->asoc.total_output_queue_size = 0;
		}
	}
	/* Check to see if some data queued, if so report it */
	for (i = 0; i < stcb->asoc.streamoutcnt; i++) {
		if (!TAILQ_EMPTY(&stcb->asoc.strmout[i].outqueue)) {
			TAILQ_FOREACH(sp, &stcb->asoc.strmout[i].outqueue, next) {
				if (sp->msg_is_complete)
					being_filled++;
				chks_in_queue++;
			}
		}
	}
	if (chks_in_queue != stcb->asoc.stream_queue_cnt) {
		SCTP_PRINTF("Hmm, stream queue cnt at %d I counted %d in stream out wheel\n",
		    stcb->asoc.stream_queue_cnt, chks_in_queue);
	}
	if (chks_in_queue) {
		/* call the output queue function */
		sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_T3, SCTP_SO_NOT_LOCKED);
		if ((TAILQ_EMPTY(&stcb->asoc.send_queue)) &&
		    (TAILQ_EMPTY(&stcb->asoc.sent_queue))) {
			/*
			 * Probably should go in and make it go back through
			 * and add fragments allowed
			 */
			if (being_filled == 0) {
				SCTP_PRINTF("Still nothing moved %d chunks are stuck\n",
				    chks_in_queue);
			}
		}
	} else {
		SCTP_PRINTF("Found no chunks on any queue tot:%lu\n",
		    (u_long)stcb->asoc.total_output_queue_size);
		stcb->asoc.total_output_queue_size = 0;
	}
}

int
sctp_heartbeat_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb,
    struct sctp_nets *net)
{
	bool net_was_pf;

	net_was_pf = (net->dest_state & SCTP_ADDR_PF) != 0;
	if (net->hb_responded == 0) {
		if (net->ro._s_addr != NULL) {
			/*
			 * Invalidate the src address if we did not get a
			 * response last time.
			 */
			sctp_free_ifa(net->ro._s_addr);
			net->ro._s_addr = NULL;
			net->src_addr_selected = 0;
		}
		sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
		if (sctp_threshold_management(inp, stcb, net, stcb->asoc.max_send_times)) {
			/* Assoc is over */
			return (1);
		}
	}
	/* Zero PBA, if it needs it */
	if (net->partial_bytes_acked > 0) {
		net->partial_bytes_acked = 0;
	}
	if ((stcb->asoc.total_output_queue_size > 0) &&
	    (TAILQ_EMPTY(&stcb->asoc.send_queue)) &&
	    (TAILQ_EMPTY(&stcb->asoc.sent_queue))) {
		sctp_audit_stream_queues_for_size(inp, stcb);
	}
	if ((((net->dest_state & SCTP_ADDR_NOHB) == 0) ||
	    (net->dest_state & SCTP_ADDR_UNCONFIRMED)) &&
	    (net_was_pf || ((net->dest_state & SCTP_ADDR_PF) == 0))) {
		/*
		 * When moving to PF during threshold management, a HB has
		 * been queued in that routine.
		 */
		uint32_t ms_gone_by;

		if ((net->last_sent_time.tv_sec > 0) ||
		    (net->last_sent_time.tv_usec > 0)) {
			struct timeval diff;

			SCTP_GETTIME_TIMEVAL(&diff);
			timevalsub(&diff, &net->last_sent_time);
			ms_gone_by = (uint32_t)(diff.tv_sec * 1000) +
			    (uint32_t)(diff.tv_usec / 1000);
		} else {
			ms_gone_by = 0xffffffff;
		}
		if ((ms_gone_by >= net->heart_beat_delay) ||
		    (net->dest_state & SCTP_ADDR_UNCONFIRMED) ||
		    (net->dest_state & SCTP_ADDR_PF)) {
			sctp_send_hb(stcb, net, SCTP_SO_NOT_LOCKED);
		}
	}
	return (0);
}

void
sctp_pathmtu_timer(struct sctp_inpcb *inp,
    struct sctp_tcb *stcb,
    struct sctp_nets *net)
{
	uint32_t next_mtu, mtu;

	next_mtu = sctp_get_next_mtu(net->mtu);

	if ((next_mtu > net->mtu) && (net->port == 0)) {
		if ((net->src_addr_selected == 0) ||
		    (net->ro._s_addr == NULL) ||
		    (net->ro._s_addr->localifa_flags & SCTP_BEING_DELETED)) {
			if ((net->ro._s_addr != NULL) && (net->ro._s_addr->localifa_flags & SCTP_BEING_DELETED)) {
				sctp_free_ifa(net->ro._s_addr);
				net->ro._s_addr = NULL;
				net->src_addr_selected = 0;
			} else if (net->ro._s_addr == NULL) {
#if defined(INET6) && defined(SCTP_EMBEDDED_V6_SCOPE)
				if (net->ro._l_addr.sa.sa_family == AF_INET6) {
					struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&net->ro._l_addr;

					/* KAME hack: embed scopeid */
					(void)sa6_embedscope(sin6, MODULE_GLOBAL(ip6_use_defzone));
				}
#endif

				net->ro._s_addr = sctp_source_address_selection(inp,
				    stcb,
				    (sctp_route_t *)&net->ro,
				    net, 0, stcb->asoc.vrf_id);
#if defined(INET6) && defined(SCTP_EMBEDDED_V6_SCOPE)
				if (net->ro._l_addr.sa.sa_family == AF_INET6) {
					struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&net->ro._l_addr;

					(void)sa6_recoverscope(sin6);
				}
#endif				/* INET6 */
			}
			if (net->ro._s_addr)
				net->src_addr_selected = 1;
		}
		if (net->ro._s_addr) {
			mtu = SCTP_GATHER_MTU_FROM_ROUTE(net->ro._s_addr, &net->ro._s_addr.sa, net->ro.ro_nh);
#if defined(INET) || defined(INET6)
			if (net->port) {
				mtu -= sizeof(struct udphdr);
			}
#endif
			if (mtu > next_mtu) {
				net->mtu = next_mtu;
			} else {
				net->mtu = mtu;
			}
		}
	}
	/* restart the timer */
	sctp_timer_start(SCTP_TIMER_TYPE_PATHMTURAISE, inp, stcb, net);
}

void
sctp_autoclose_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
{
	struct timeval tn, *tim_touse;
	struct sctp_association *asoc;
	uint32_t ticks_gone_by;

	(void)SCTP_GETTIME_TIMEVAL(&tn);
	if (stcb->asoc.sctp_autoclose_ticks > 0 &&
	    sctp_is_feature_on(inp, SCTP_PCB_FLAGS_AUTOCLOSE)) {
		/* Auto close is on */
		asoc = &stcb->asoc;
		/* pick the time to use */
		if (asoc->time_last_rcvd.tv_sec >
		    asoc->time_last_sent.tv_sec) {
			tim_touse = &asoc->time_last_rcvd;
		} else {
			tim_touse = &asoc->time_last_sent;
		}
		/* Now has long enough transpired to autoclose? */
		ticks_gone_by = sctp_secs_to_ticks((uint32_t)(tn.tv_sec - tim_touse->tv_sec));
		if (ticks_gone_by >= asoc->sctp_autoclose_ticks) {
			/*
			 * autoclose time has hit, call the output routine,
			 * which should do nothing just to be SURE we don't
			 * have hanging data. We can then safely check the
			 * queues and know that we are clear to send
			 * shutdown
			 */
			sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_AUTOCLOSE_TMR, SCTP_SO_NOT_LOCKED);
			/* Are we clean? */
			if (TAILQ_EMPTY(&asoc->send_queue) &&
			    TAILQ_EMPTY(&asoc->sent_queue)) {
				/*
				 * there is nothing queued to send, so I'm
				 * done...
				 */
				if (SCTP_GET_STATE(stcb) != SCTP_STATE_SHUTDOWN_SENT) {
					/* only send SHUTDOWN 1st time thru */
					struct sctp_nets *net;

					if ((SCTP_GET_STATE(stcb) == SCTP_STATE_OPEN) ||
					    (SCTP_GET_STATE(stcb) == SCTP_STATE_SHUTDOWN_RECEIVED)) {
						SCTP_STAT_DECR_GAUGE32(sctps_currestab);
					}
					SCTP_SET_STATE(stcb, SCTP_STATE_SHUTDOWN_SENT);
					sctp_stop_timers_for_shutdown(stcb);
					if (stcb->asoc.alternate) {
						net = stcb->asoc.alternate;
					} else {
						net = stcb->asoc.primary_destination;
					}
					sctp_send_shutdown(stcb, net);
					sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWN,
					    stcb->sctp_ep, stcb, net);
					sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
					    stcb->sctp_ep, stcb, NULL);
				}
			}
		} else {
			/*
			 * No auto close at this time, reset t-o to check
			 * later
			 */
			uint32_t tmp;

			/* fool the timer startup to use the time left */
			tmp = asoc->sctp_autoclose_ticks;
			asoc->sctp_autoclose_ticks -= ticks_gone_by;
			sctp_timer_start(SCTP_TIMER_TYPE_AUTOCLOSE, inp, stcb, NULL);
			/* restore the real tick value */
			asoc->sctp_autoclose_ticks = tmp;
		}
	}
}