text: /*-
   * Copyright (c) 2001-2008, 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.
   */
  
  #ifdef __FreeBSD__
  #include <sys/cdefs.h>
  __FBSDID("$FreeBSD: head/sys/netinet/sctp_input.c 301666 2016-06-08 17:57:42Z tuexen $");
  #endif
  
  #include <netinet/sctp_os.h>
  #include <netinet/sctp_var.h>
  #include <netinet/sctp_sysctl.h>
  #include <netinet/sctp_pcb.h>
  #include <netinet/sctp_header.h>
  #include <netinet/sctputil.h>
  #include <netinet/sctp_output.h>
  #include <netinet/sctp_input.h>
  #include <netinet/sctp_auth.h>
  #include <netinet/sctp_indata.h>
  #include <netinet/sctp_asconf.h>
  #include <netinet/sctp_bsd_addr.h>
  #include <netinet/sctp_timer.h>
  #include <netinet/sctp_crc32.h>
  #if defined(INET) || defined(INET6)
  #if !defined(__Userspace_os_Windows)
  #include <netinet/udp.h>
  #endif
  #endif
  #if defined(__FreeBSD__)
  #include <sys/smp.h>
  #endif
  
  #if defined(__APPLE__)
  #define APPLE_FILE_NO 2
  #endif
  
  
  static void
  sctp_stop_all_cookie_timers(struct sctp_tcb *stcb)
  {
  	struct sctp_nets *net;
  
  	/* This now not only stops all cookie timers
  	 * it also stops any INIT timers as well. This
  	 * will make sure that the timers are stopped in
  	 * all collision cases.
  	 */
  	SCTP_TCB_LOCK_ASSERT(stcb);
  	TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) {
  		if (net->rxt_timer.type == SCTP_TIMER_TYPE_COOKIE) {
  			sctp_timer_stop(SCTP_TIMER_TYPE_COOKIE,
  					stcb->sctp_ep,
  					stcb,
  					net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_1);
  		} else if (net->rxt_timer.type == SCTP_TIMER_TYPE_INIT) {
  			sctp_timer_stop(SCTP_TIMER_TYPE_INIT,
  					stcb->sctp_ep,
  					stcb,
  					net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_2);
  		}
  	}
  }
  
  /* INIT handler */
  static void
  sctp_handle_init(struct mbuf *m, int iphlen, int offset,
                   struct sockaddr *src, struct sockaddr *dst, struct sctphdr *sh,
                   struct sctp_init_chunk *cp, struct sctp_inpcb *inp,
                   struct sctp_tcb *stcb, struct sctp_nets *net, int *abort_no_unlock,
  #if defined(__FreeBSD__)
                   uint8_t mflowtype, uint32_t mflowid,
  #endif
                   uint32_t vrf_id, uint16_t port)
  {
  	struct sctp_init *init;
  	struct mbuf *op_err;
  
  	SCTPDBG(SCTP_DEBUG_INPUT2, "sctp_handle_init: handling INIT tcb:%p\n",
  		(void *)stcb);
  	if (stcb == NULL) {
  		SCTP_INP_RLOCK(inp);
  	}
  	/* validate length */
  	if (ntohs(cp->ch.chunk_length) < sizeof(struct sctp_init_chunk)) {
  		op_err = sctp_generate_cause(SCTP_CAUSE_INVALID_PARAM, "");
  		sctp_abort_association(inp, stcb, m, iphlen, src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  		                       mflowtype, mflowid,
  #endif
  				       vrf_id, port);
  		if (stcb)
  			*abort_no_unlock = 1;
  		goto outnow;
  	}
  	/* validate parameters */
  	init = &cp->init;
  	if (init->initiate_tag == 0) {
  		/* protocol error... send abort */
  		op_err = sctp_generate_cause(SCTP_CAUSE_INVALID_PARAM, "");
  		sctp_abort_association(inp, stcb, m, iphlen, src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  		                       mflowtype, mflowid,
  #endif
  				       vrf_id, port);
  		if (stcb)
  			*abort_no_unlock = 1;
  		goto outnow;
  	}
  	if (ntohl(init->a_rwnd) < SCTP_MIN_RWND) {
  		/* invalid parameter... send abort */
  		op_err = sctp_generate_cause(SCTP_CAUSE_INVALID_PARAM, "");
  		sctp_abort_association(inp, stcb, m, iphlen, src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  		                       mflowtype, mflowid,
  #endif
  				       vrf_id, port);
  		if (stcb)
  			*abort_no_unlock = 1;
  		goto outnow;
  	}
  	if (init->num_inbound_streams == 0) {
  		/* protocol error... send abort */
  		op_err = sctp_generate_cause(SCTP_CAUSE_INVALID_PARAM, "");
  		sctp_abort_association(inp, stcb, m, iphlen, src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  		                       mflowtype, mflowid,
  #endif
  				       vrf_id, port);
  		if (stcb)
  			*abort_no_unlock = 1;
  		goto outnow;
  	}
  	if (init->num_outbound_streams == 0) {
  		/* protocol error... send abort */
  		op_err = sctp_generate_cause(SCTP_CAUSE_INVALID_PARAM, "");
  		sctp_abort_association(inp, stcb, m, iphlen, src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  		                       mflowtype, mflowid,
  #endif
  				       vrf_id, port);
  		if (stcb)
  			*abort_no_unlock = 1;
  		goto outnow;
  	}
  	if (sctp_validate_init_auth_params(m, offset + sizeof(*cp),
  					   offset + ntohs(cp->ch.chunk_length))) {
  		/* auth parameter(s) error... send abort */
  		op_err = sctp_generate_cause(SCTP_BASE_SYSCTL(sctp_diag_info_code),
  		                             "Problem with AUTH parameters");
  		sctp_abort_association(inp, stcb, m, iphlen, src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  		                       mflowtype, mflowid,
  #endif
  		                       vrf_id, port);
  		if (stcb)
  			*abort_no_unlock = 1;
  		goto outnow;
  	}
  	/* We are only accepting if we have a socket with positive so_qlimit.*/
  	if ((stcb == NULL) &&
  	    ((inp->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) ||
  	     (inp->sctp_flags & SCTP_PCB_FLAGS_SOCKET_ALLGONE) ||
  	     (inp->sctp_socket == NULL) ||
  	     (inp->sctp_socket->so_qlimit == 0))) {
  		/*
  		 * FIX ME ?? What about TCP model and we have a
  		 * match/restart case? Actually no fix is needed.
  		 * the lookup will always find the existing assoc so stcb
  		 * would not be NULL. It may be questionable to do this
  		 * since we COULD just send back the INIT-ACK and hope that
  		 * the app did accept()'s by the time the COOKIE was sent. But
  		 * there is a price to pay for COOKIE generation and I don't
  		 * want to pay it on the chance that the app will actually do
  		 * some accepts(). The App just looses and should NOT be in
  		 * this state :-)
  		 */
  		if (SCTP_BASE_SYSCTL(sctp_blackhole) == 0) {
  			op_err = sctp_generate_cause(SCTP_BASE_SYSCTL(sctp_diag_info_code),
  			                             "No listener");
  			sctp_send_abort(m, iphlen, src, dst, sh, 0, op_err,
  #if defined(__FreeBSD__)
  			                mflowtype, mflowid, inp->fibnum,
  #endif
  			                vrf_id, port);
  		}
  		goto outnow;
  	}
  	if ((stcb != NULL) &&
  	    (SCTP_GET_STATE(&stcb->asoc) == SCTP_STATE_SHUTDOWN_ACK_SENT)) {
  		SCTPDBG(SCTP_DEBUG_INPUT3, "sctp_handle_init: sending SHUTDOWN-ACK\n");
  		sctp_send_shutdown_ack(stcb, NULL);
  		sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_CONTROL_PROC, SCTP_SO_NOT_LOCKED);
  	} else {
  		SCTPDBG(SCTP_DEBUG_INPUT3, "sctp_handle_init: sending INIT-ACK\n");
  		sctp_send_initiate_ack(inp, stcb, net, m, iphlen, offset,
  		                       src, dst, sh, cp,
  #if defined(__FreeBSD__)
  		                       mflowtype, mflowid,
  #endif
  		                       vrf_id, port,
  		                       ((stcb == NULL) ? SCTP_HOLDS_LOCK : SCTP_NOT_LOCKED));
  	}
   outnow:
  	if (stcb == NULL) {
  		SCTP_INP_RUNLOCK(inp);
  	}
  }
  
  /*
   * process peer "INIT/INIT-ACK" chunk returns value < 0 on error
   */
  
  int
  sctp_is_there_unsent_data(struct sctp_tcb *stcb, int so_locked
  #if !defined(__APPLE__) && !defined(SCTP_SO_LOCK_TESTING)
  	SCTP_UNUSED
  #endif
  )
  {
  	int unsent_data = 0;
  	unsigned int i;
  	struct sctp_stream_queue_pending *sp;
  	struct sctp_association *asoc;
  
  	/* This function returns the number of streams that have
  	 * true unsent data on them. Note that as it looks through
  	 * it will clean up any places that have old data that
  	 * has been sent but left at top of stream queue.
  	 */
  	asoc = &stcb->asoc;
  	SCTP_TCB_SEND_LOCK(stcb);
  	if (!stcb->asoc.ss_functions.sctp_ss_is_empty(stcb, asoc)) {
  		/* Check to see if some data queued */
  		for (i = 0; i < stcb->asoc.streamoutcnt; i++) {
  			/*sa_ignore FREED_MEMORY*/
  			sp = TAILQ_FIRST(&stcb->asoc.strmout[i].outqueue);
  			if (sp == NULL) {
  				continue;
  			}
  			if ((sp->msg_is_complete) &&
  			    (sp->length == 0)  &&
  			    (sp->sender_all_done)) {
  				/* We are doing differed cleanup. Last
  				 * time through when we took all the data
  				 * the sender_all_done was not set.
  				 */
  				if (sp->put_last_out == 0) {
  					SCTP_PRINTF("Gak, put out entire msg with NO end!-1\n");
  					SCTP_PRINTF("sender_done:%d len:%d msg_comp:%d put_last_out:%d\n",
  					            sp->sender_all_done,
  					            sp->length,
  					            sp->msg_is_complete,
  					            sp->put_last_out);
  				}
  				atomic_subtract_int(&stcb->asoc.stream_queue_cnt, 1);
  				TAILQ_REMOVE(&stcb->asoc.strmout[i].outqueue, sp, next);
  				if (sp->net) {
  					sctp_free_remote_addr(sp->net);
  					sp->net = NULL;
  				}
  				if (sp->data) {
  					sctp_m_freem(sp->data);
  					sp->data = NULL;
  				}
  				sctp_free_a_strmoq(stcb, sp, so_locked);
  			} else {
  				unsent_data++;
  				break;
  			}
  		}
  	}
  	SCTP_TCB_SEND_UNLOCK(stcb);
  	return (unsent_data);
  }
  
  static int
  sctp_process_init(struct sctp_init_chunk *cp, struct sctp_tcb *stcb)
  {
  	struct sctp_init *init;
  	struct sctp_association *asoc;
  	struct sctp_nets *lnet;
  	unsigned int i;
  
  	init = &cp->init;
  	asoc = &stcb->asoc;
  	/* save off parameters */
  	asoc->peer_vtag = ntohl(init->initiate_tag);
  	asoc->peers_rwnd = ntohl(init->a_rwnd);
  	/* init tsn's */
  	asoc->highest_tsn_inside_map = asoc->asconf_seq_in = ntohl(init->initial_tsn) - 1;
  
  	if (!TAILQ_EMPTY(&asoc->nets)) {
  		/* update any ssthresh's that may have a default */
  		TAILQ_FOREACH(lnet, &asoc->nets, sctp_next) {
  			lnet->ssthresh = asoc->peers_rwnd;
  			if (SCTP_BASE_SYSCTL(sctp_logging_level) & (SCTP_CWND_MONITOR_ENABLE|SCTP_CWND_LOGGING_ENABLE)) {
  				sctp_log_cwnd(stcb, lnet, 0, SCTP_CWND_INITIALIZATION);
  			}
  
  		}
  	}
  	SCTP_TCB_SEND_LOCK(stcb);
  	if (asoc->pre_open_streams > ntohs(init->num_inbound_streams)) {
  		unsigned int newcnt;
  		struct sctp_stream_out *outs;
  		struct sctp_stream_queue_pending *sp, *nsp;
  		struct sctp_tmit_chunk *chk, *nchk;
  
  		/* abandon the upper streams */
  		newcnt = ntohs(init->num_inbound_streams);
  		TAILQ_FOREACH_SAFE(chk, &asoc->send_queue, sctp_next, nchk) {
  			if (chk->rec.data.stream_number >= newcnt) {
  				TAILQ_REMOVE(&asoc->send_queue, chk, sctp_next);
  				asoc->send_queue_cnt--;
  				if (asoc->strmout[chk->rec.data.stream_number].chunks_on_queues > 0) {
  					asoc->strmout[chk->rec.data.stream_number].chunks_on_queues--;
  #ifdef INVARIANTS
  				} else {
  					panic("No chunks on the queues for sid %u.", chk->rec.data.stream_number);
  #endif
  				}
  				if (chk->data != NULL) {
  					sctp_free_bufspace(stcb, asoc, chk, 1);
  					sctp_ulp_notify(SCTP_NOTIFY_UNSENT_DG_FAIL, stcb,
  					                0, chk, SCTP_SO_NOT_LOCKED);
  					if (chk->data) {
  						sctp_m_freem(chk->data);
  						chk->data = NULL;
  					}
  				}
  				sctp_free_a_chunk(stcb, chk, SCTP_SO_NOT_LOCKED);
  				/*sa_ignore FREED_MEMORY*/
  			}
  		}
  		if (asoc->strmout) {
  			for (i = newcnt; i < asoc->pre_open_streams; i++) {
  				outs = &asoc->strmout[i];
  				TAILQ_FOREACH_SAFE(sp, &outs->outqueue, next, nsp) {
  					TAILQ_REMOVE(&outs->outqueue, sp, next);
  					asoc->stream_queue_cnt--;
  					sctp_ulp_notify(SCTP_NOTIFY_SPECIAL_SP_FAIL,
  					    stcb, 0, sp, SCTP_SO_NOT_LOCKED);
  					if (sp->data) {
  						sctp_m_freem(sp->data);
  						sp->data = NULL;
  					}
  					if (sp->net) {
  						sctp_free_remote_addr(sp->net);
  						sp->net = NULL;
  					}
  					/* Free the chunk */
  					sctp_free_a_strmoq(stcb, sp, SCTP_SO_NOT_LOCKED);
  					/*sa_ignore FREED_MEMORY*/
  				}
  				outs->state = SCTP_STREAM_CLOSED;
  			}
  		}
  		/* cut back the count */
  		asoc->pre_open_streams = newcnt;
  	}
  	SCTP_TCB_SEND_UNLOCK(stcb);
  	asoc->streamoutcnt = asoc->pre_open_streams;
  	if (asoc->strmout) {
  		for (i = 0; i < asoc->streamoutcnt; i++) {
  			asoc->strmout[i].state = SCTP_STREAM_OPEN;
  		}
  	}
  	/* EY - nr_sack: initialize highest tsn in nr_mapping_array */
  	asoc->highest_tsn_inside_nr_map = asoc->highest_tsn_inside_map;
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MAP_LOGGING_ENABLE) {
  		sctp_log_map(0, 5, asoc->highest_tsn_inside_map, SCTP_MAP_SLIDE_RESULT);
  	}
  	/* This is the next one we expect */
  	asoc->str_reset_seq_in = asoc->asconf_seq_in + 1;
  
  	asoc->mapping_array_base_tsn = ntohl(init->initial_tsn);
  	asoc->tsn_last_delivered = asoc->cumulative_tsn = asoc->asconf_seq_in;
  
  	asoc->advanced_peer_ack_point = asoc->last_acked_seq;
  	/* open the requested streams */
  
  	if (asoc->strmin != NULL) {
  		/* Free the old ones */
  		for (i = 0; i < asoc->streamincnt; i++) {
  			sctp_clean_up_stream(stcb, &asoc->strmin[i].inqueue);
  			sctp_clean_up_stream(stcb, &asoc->strmin[i].uno_inqueue);
  		}
  		SCTP_FREE(asoc->strmin, SCTP_M_STRMI);
  	}
  	if (asoc->max_inbound_streams > ntohs(init->num_outbound_streams)) {
  		asoc->streamincnt = ntohs(init->num_outbound_streams);
  	} else {
  		asoc->streamincnt = asoc->max_inbound_streams;
  	}
  	SCTP_MALLOC(asoc->strmin, struct sctp_stream_in *, asoc->streamincnt *
  		    sizeof(struct sctp_stream_in), SCTP_M_STRMI);
  	if (asoc->strmin == NULL) {
  		/* we didn't get memory for the streams! */
  		SCTPDBG(SCTP_DEBUG_INPUT2, "process_init: couldn't get memory for the streams!\n");
  		return (-1);
  	}
  	for (i = 0; i < asoc->streamincnt; i++) {
  		asoc->strmin[i].stream_no = i;
  		asoc->strmin[i].last_sequence_delivered = 0xffffffff;
  		TAILQ_INIT(&asoc->strmin[i].inqueue);
  		TAILQ_INIT(&asoc->strmin[i].uno_inqueue);
  		asoc->strmin[i].pd_api_started = 0;
  		asoc->strmin[i].delivery_started = 0;
  	}
  	/*
  	 * load_address_from_init will put the addresses into the
  	 * association when the COOKIE is processed or the INIT-ACK is
  	 * processed. Both types of COOKIE's existing and new call this
  	 * routine. It will remove addresses that are no longer in the
  	 * association (for the restarting case where addresses are
  	 * removed). Up front when the INIT arrives we will discard it if it
  	 * is a restart and new addresses have been added.
  	 */
  	/* sa_ignore MEMLEAK */
  	return (0);
  }
  
  /*
   * INIT-ACK message processing/consumption returns value < 0 on error
   */
  static int
  sctp_process_init_ack(struct mbuf *m, int iphlen, int offset,
                        struct sockaddr *src, struct sockaddr *dst, struct sctphdr *sh,
                        struct sctp_init_ack_chunk *cp, struct sctp_tcb *stcb,
                        struct sctp_nets *net, int *abort_no_unlock,
  #if defined(__FreeBSD__)
  		      uint8_t mflowtype, uint32_t mflowid,
  #endif
                        uint32_t vrf_id)
  {
  	struct sctp_association *asoc;
  	struct mbuf *op_err;
  	int retval, abort_flag;
  	uint32_t initack_limit;
  	int nat_friendly = 0;
  
  	/* First verify that we have no illegal param's */
  	abort_flag = 0;
  
  	op_err = sctp_arethere_unrecognized_parameters(m,
  						       (offset + sizeof(struct sctp_init_chunk)),
  						       &abort_flag, (struct sctp_chunkhdr *)cp, &nat_friendly);
  	if (abort_flag) {
  		/* Send an abort and notify peer */
  		sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  		*abort_no_unlock = 1;
  		return (-1);
  	}
  	asoc = &stcb->asoc;
  	asoc->peer_supports_nat = (uint8_t)nat_friendly;
  	/* process the peer's parameters in the INIT-ACK */
  	retval = sctp_process_init((struct sctp_init_chunk *)cp, stcb);
  	if (retval < 0) {
  		return (retval);
  	}
  	initack_limit = offset + ntohs(cp->ch.chunk_length);
  	/* load all addresses */
  	if ((retval = sctp_load_addresses_from_init(stcb, m,
  	    (offset + sizeof(struct sctp_init_chunk)), initack_limit,
  	    src, dst, NULL, stcb->asoc.port))) {
  		op_err = sctp_generate_cause(SCTP_BASE_SYSCTL(sctp_diag_info_code),
  		                             "Problem with address parameters");
  		SCTPDBG(SCTP_DEBUG_INPUT1,
  			"Load addresses from INIT causes an abort %d\n",
  			retval);
  		sctp_abort_association(stcb->sctp_ep, stcb, m, iphlen,
  		                       src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  		                       mflowtype, mflowid,
  #endif
  		                       vrf_id, net->port);
  		*abort_no_unlock = 1;
  		return (-1);
  	}
  	/* if the peer doesn't support asconf, flush the asconf queue */
  	if (asoc->asconf_supported == 0) {
  		struct sctp_asconf_addr *param, *nparam;
  
  		TAILQ_FOREACH_SAFE(param, &asoc->asconf_queue, next, nparam) {
  			TAILQ_REMOVE(&asoc->asconf_queue, param, next);
  			SCTP_FREE(param, SCTP_M_ASC_ADDR);
  		}
  	}
  
  	stcb->asoc.peer_hmac_id = sctp_negotiate_hmacid(stcb->asoc.peer_hmacs,
  	    stcb->asoc.local_hmacs);
  	if (op_err) {
  		sctp_queue_op_err(stcb, op_err);
  		/* queuing will steal away the mbuf chain to the out queue */
  		op_err = NULL;
  	}
  	/* extract the cookie and queue it to "echo" it back... */
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
  		sctp_misc_ints(SCTP_THRESHOLD_CLEAR,
  			       stcb->asoc.overall_error_count,
  			       0,
  			       SCTP_FROM_SCTP_INPUT,
  			       __LINE__);
  	}
  	stcb->asoc.overall_error_count = 0;
  	net->error_count = 0;
  
  	/*
  	 * Cancel the INIT timer, We do this first before queueing the
  	 * cookie. We always cancel at the primary to assue that we are
  	 * canceling the timer started by the INIT which always goes to the
  	 * primary.
  	 */
  	sctp_timer_stop(SCTP_TIMER_TYPE_INIT, stcb->sctp_ep, stcb,
  	    asoc->primary_destination, SCTP_FROM_SCTP_INPUT + SCTP_LOC_3);
  
  	/* calculate the RTO */
  	net->RTO = sctp_calculate_rto(stcb, asoc, net, &asoc->time_entered, sctp_align_safe_nocopy,
  				      SCTP_RTT_FROM_NON_DATA);
  #if defined(__Userspace__)
  	if (stcb->sctp_ep->recv_callback) {
  		if (stcb->sctp_socket) {
  			uint32_t inqueue_bytes, sb_free_now;
  			struct sctp_inpcb *inp;
  
  			inp = stcb->sctp_ep;
  			inqueue_bytes = stcb->asoc.total_output_queue_size - (stcb->asoc.chunks_on_out_queue * sizeof(struct sctp_data_chunk));
  			sb_free_now = SCTP_SB_LIMIT_SND(stcb->sctp_socket) - (inqueue_bytes + stcb->asoc.sb_send_resv);
  
  			/* check if the amount free in the send socket buffer crossed the threshold */
  			if (inp->send_callback &&
  			    (((inp->send_sb_threshold > 0) &&
  			      (sb_free_now >= inp->send_sb_threshold) &&
  			      (stcb->asoc.chunks_on_out_queue <= SCTP_BASE_SYSCTL(sctp_max_chunks_on_queue))) ||
  			     (inp->send_sb_threshold == 0))) {
  				atomic_add_int(&stcb->asoc.refcnt, 1);
  				SCTP_TCB_UNLOCK(stcb);
  				inp->send_callback(stcb->sctp_socket, sb_free_now);
  				SCTP_TCB_LOCK(stcb);
  				atomic_subtract_int(&stcb->asoc.refcnt, 1);
  			}
  		}
  	}
  #endif
  	retval = sctp_send_cookie_echo(m, offset, stcb, net);
  	if (retval < 0) {
  		/*
  		 * No cookie, we probably should send a op error. But in any
  		 * case if there is no cookie in the INIT-ACK, we can
  		 * abandon the peer, its broke.
  		 */
  		if (retval == -3) {
  			uint16_t len;
  
  			len = (uint16_t)(sizeof(struct sctp_error_missing_param) + sizeof(uint16_t));
  			/* We abort with an error of missing mandatory param */
  			op_err = sctp_get_mbuf_for_msg(len, 0, M_NOWAIT, 1, MT_DATA);
  			if (op_err != NULL) {
  				struct sctp_error_missing_param *cause;
  
  				SCTP_BUF_LEN(op_err) = len;
  				cause = mtod(op_err, struct sctp_error_missing_param *);
  				/* Subtract the reserved param */
  				cause->cause.code = htons(SCTP_CAUSE_MISSING_PARAM);
  				cause->cause.length = htons(len);
  				cause->num_missing_params = htonl(1);
  				cause->type[0] = htons(SCTP_STATE_COOKIE);
  			}
  			sctp_abort_association(stcb->sctp_ep, stcb, m, iphlen,
  			                       src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  			                       mflowtype, mflowid,
  #endif
  			                       vrf_id, net->port);
  			*abort_no_unlock = 1;
  		}
  		return (retval);
  	}
  
  	return (0);
  }
  
  static void
  sctp_handle_heartbeat_ack(struct sctp_heartbeat_chunk *cp,
      struct sctp_tcb *stcb, struct sctp_nets *net)
  {
  	union sctp_sockstore store;
  	struct sctp_nets *r_net, *f_net;
  	struct timeval tv;
  	int req_prim = 0;
  	uint16_t old_error_counter;
  
  	if (ntohs(cp->ch.chunk_length) != sizeof(struct sctp_heartbeat_chunk)) {
  		/* Invalid length */
  		return;
  	}
  
  	memset(&store, 0, sizeof(store));
  	switch (cp->heartbeat.hb_info.addr_family) {
  #ifdef INET
  	case AF_INET:
  		if (cp->heartbeat.hb_info.addr_len == sizeof(struct sockaddr_in)) {
  			store.sin.sin_family = cp->heartbeat.hb_info.addr_family;
  #ifdef HAVE_SIN_LEN
  			store.sin.sin_len = cp->heartbeat.hb_info.addr_len;
  #endif
  			store.sin.sin_port = stcb->rport;
  			memcpy(&store.sin.sin_addr, cp->heartbeat.hb_info.address,
  			       sizeof(store.sin.sin_addr));
  		} else {
  			return;
  		}
  		break;
  #endif
  #ifdef INET6
  	case AF_INET6:
  		if (cp->heartbeat.hb_info.addr_len == sizeof(struct sockaddr_in6)) {
  			store.sin6.sin6_family = cp->heartbeat.hb_info.addr_family;
  #ifdef HAVE_SIN6_LEN
  			store.sin6.sin6_len = cp->heartbeat.hb_info.addr_len;
  #endif
  			store.sin6.sin6_port = stcb->rport;
  			memcpy(&store.sin6.sin6_addr, cp->heartbeat.hb_info.address, sizeof(struct in6_addr));
  		} else {
  			return;
  		}
  		break;
  #endif
  #if defined(__Userspace__)
  	case AF_CONN:
  		if (cp->heartbeat.hb_info.addr_len == sizeof(struct sockaddr_conn)) {
  			store.sconn.sconn_family = cp->heartbeat.hb_info.addr_family;
  #ifdef HAVE_SCONN_LEN
  			store.sconn.sconn_len = cp->heartbeat.hb_info.addr_len;
  #endif
  			store.sconn.sconn_port = stcb->rport;
  			memcpy(&store.sconn.sconn_addr, cp->heartbeat.hb_info.address, sizeof(void *));
  		} else {
  			return;
  		}
  		break;
  #endif
  	default:
  		return;
  	}
  	r_net = sctp_findnet(stcb, &store.sa);
  	if (r_net == NULL) {
  		SCTPDBG(SCTP_DEBUG_INPUT1, "Huh? I can't find the address I sent it to, discard\n");
  		return;
  	}
  	if ((r_net && (r_net->dest_state & SCTP_ADDR_UNCONFIRMED)) &&
  	    (r_net->heartbeat_random1 == cp->heartbeat.hb_info.random_value1) &&
  	    (r_net->heartbeat_random2 == cp->heartbeat.hb_info.random_value2)) {
  		/*
  		 * If the its a HB and it's random value is correct when can
  		 * confirm the destination.
  		 */
  		r_net->dest_state &= ~SCTP_ADDR_UNCONFIRMED;
  		if (r_net->dest_state & SCTP_ADDR_REQ_PRIMARY) {
  			stcb->asoc.primary_destination = r_net;
  			r_net->dest_state &= ~SCTP_ADDR_REQ_PRIMARY;
  			f_net = TAILQ_FIRST(&stcb->asoc.nets);
  			if (f_net != r_net) {
  				/* first one on the list is NOT the primary
  				 * sctp_cmpaddr() is much more efficient if
  				 * the primary is the first on the list, make it
  				 * so.
  				 */
  				TAILQ_REMOVE(&stcb->asoc.nets, r_net, sctp_next);
  				TAILQ_INSERT_HEAD(&stcb->asoc.nets, r_net, sctp_next);
  			}
  			req_prim = 1;
  		}
  		sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_CONFIRMED,
  		    stcb, 0, (void *)r_net, SCTP_SO_NOT_LOCKED);
  		sctp_timer_stop(SCTP_TIMER_TYPE_HEARTBEAT, stcb->sctp_ep, stcb,
  		                r_net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_4);
  		sctp_timer_start(SCTP_TIMER_TYPE_HEARTBEAT, stcb->sctp_ep, stcb, r_net);
  	}
  	old_error_counter = r_net->error_count;
  	r_net->error_count = 0;
  	r_net->hb_responded = 1;
  	tv.tv_sec = cp->heartbeat.hb_info.time_value_1;
  	tv.tv_usec = cp->heartbeat.hb_info.time_value_2;
  	/* Now lets do a RTO with this */
  	r_net->RTO = sctp_calculate_rto(stcb, &stcb->asoc, r_net, &tv, sctp_align_safe_nocopy,
  					SCTP_RTT_FROM_NON_DATA);
  	if (!(r_net->dest_state & SCTP_ADDR_REACHABLE)) {
  		r_net->dest_state |= SCTP_ADDR_REACHABLE;
  		sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_UP, stcb,
  				0, (void *)r_net, SCTP_SO_NOT_LOCKED);
  	}
  	if (r_net->dest_state & SCTP_ADDR_PF) {
  		r_net->dest_state &= ~SCTP_ADDR_PF;
  		stcb->asoc.cc_functions.sctp_cwnd_update_exit_pf(stcb, net);
  	}
  	if (old_error_counter > 0) {
  		sctp_timer_stop(SCTP_TIMER_TYPE_HEARTBEAT, stcb->sctp_ep,
  		                stcb, r_net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_5);
  		sctp_timer_start(SCTP_TIMER_TYPE_HEARTBEAT, stcb->sctp_ep, stcb, r_net);
  	}
  	if (r_net == stcb->asoc.primary_destination) {
  		if (stcb->asoc.alternate) {
  			/* release the alternate, primary is good */
  			sctp_free_remote_addr(stcb->asoc.alternate);
  			stcb->asoc.alternate = NULL;
  		}
  	}
  	/* Mobility adaptation */
  	if (req_prim) {
  		if ((sctp_is_mobility_feature_on(stcb->sctp_ep,
  		                                 SCTP_MOBILITY_BASE) ||
  		    sctp_is_mobility_feature_on(stcb->sctp_ep,
  		                                SCTP_MOBILITY_FASTHANDOFF)) &&
  		    sctp_is_mobility_feature_on(stcb->sctp_ep,
  		                                SCTP_MOBILITY_PRIM_DELETED)) {
  
  			sctp_timer_stop(SCTP_TIMER_TYPE_PRIM_DELETED,
  			                stcb->sctp_ep, stcb, NULL,
  			                SCTP_FROM_SCTP_INPUT + SCTP_LOC_6);
  			if (sctp_is_mobility_feature_on(stcb->sctp_ep,
  					SCTP_MOBILITY_FASTHANDOFF)) {
  				sctp_assoc_immediate_retrans(stcb,
  					stcb->asoc.primary_destination);
  			}
  			if (sctp_is_mobility_feature_on(stcb->sctp_ep,
  					SCTP_MOBILITY_BASE)) {
  				sctp_move_chunks_from_net(stcb,
  					stcb->asoc.deleted_primary);
  			}
  			sctp_delete_prim_timer(stcb->sctp_ep, stcb,
  					stcb->asoc.deleted_primary);
  		}
  	}
  }
  
  static int
  sctp_handle_nat_colliding_state(struct sctp_tcb *stcb)
  {
  	/* return 0 means we want you to proceed with the abort
  	 * non-zero means no abort processing
  	*/
  	struct sctpasochead *head;
  
  	if (SCTP_GET_STATE(&stcb->asoc) == SCTP_STATE_COOKIE_WAIT) {
  		/* generate a new vtag and send init */
  		LIST_REMOVE(stcb, sctp_asocs);
  		stcb->asoc.my_vtag = sctp_select_a_tag(stcb->sctp_ep, stcb->sctp_ep->sctp_lport, stcb->rport, 1);
  		head = &SCTP_BASE_INFO(sctp_asochash)[SCTP_PCBHASH_ASOC(stcb->asoc.my_vtag, SCTP_BASE_INFO(hashasocmark))];
  		/* put it in the bucket in the vtag hash of assoc's for the system */
  		LIST_INSERT_HEAD(head, stcb, sctp_asocs);
  		sctp_send_initiate(stcb->sctp_ep, stcb, SCTP_SO_NOT_LOCKED);
  		return (1);
  	}
  	if (SCTP_GET_STATE(&stcb->asoc) == SCTP_STATE_COOKIE_ECHOED) {
  		/* treat like a case where the cookie expired i.e.:
  		* - dump current cookie.
  		* - generate a new vtag.
  		* - resend init.
  		*/
  		/* generate a new vtag and send init */
  		LIST_REMOVE(stcb, sctp_asocs);
  		stcb->asoc.state &= ~SCTP_STATE_COOKIE_ECHOED;
  		stcb->asoc.state |= SCTP_STATE_COOKIE_WAIT;
  		sctp_stop_all_cookie_timers(stcb);
  		sctp_toss_old_cookies(stcb, &stcb->asoc);
  		stcb->asoc.my_vtag = sctp_select_a_tag(stcb->sctp_ep, stcb->sctp_ep->sctp_lport, stcb->rport,  1);
  		head = &SCTP_BASE_INFO(sctp_asochash)[SCTP_PCBHASH_ASOC(stcb->asoc.my_vtag, SCTP_BASE_INFO(hashasocmark))];
  		/* put it in the bucket in the vtag hash of assoc's for the system */
  		LIST_INSERT_HEAD(head, stcb, sctp_asocs);
  		sctp_send_initiate(stcb->sctp_ep, stcb, SCTP_SO_NOT_LOCKED);
  		return (1);
  	}
  	return (0);
  }
  
  static int
  sctp_handle_nat_missing_state(struct sctp_tcb *stcb,
  			      struct sctp_nets *net)
  {
  	/* return 0 means we want you to proceed with the abort
  	 * non-zero means no abort processing
  	 */
  	if (stcb->asoc.auth_supported == 0) {
  		SCTPDBG(SCTP_DEBUG_INPUT2, "sctp_handle_nat_missing_state: Peer does not support AUTH, cannot send an asconf\n");
  		return (0);
  	}
  	sctp_asconf_send_nat_state_update(stcb, net);
  	return (1);
  }
  
  
  static void
  sctp_handle_abort(struct sctp_abort_chunk *abort,
      struct sctp_tcb *stcb, struct sctp_nets *net)
  {
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  	struct socket *so;
  #endif
  	uint16_t len;
  	uint16_t error;
  
  	SCTPDBG(SCTP_DEBUG_INPUT2, "sctp_handle_abort: handling ABORT\n");
  	if (stcb == NULL)
  		return;
  
  	len = ntohs(abort->ch.chunk_length);
  	if (len > sizeof (struct sctp_chunkhdr)) {
  		/* Need to check the cause codes for our
  		 * two magic nat aborts which don't kill the assoc
  		 * necessarily.
  		 */
  		struct sctp_gen_error_cause *cause;
  
  		cause = (struct sctp_gen_error_cause *)(abort + 1);
  		error = ntohs(cause->code);
  		if (error == SCTP_CAUSE_NAT_COLLIDING_STATE) {
  			SCTPDBG(SCTP_DEBUG_INPUT2, "Received Colliding state abort flags:%x\n",
  			                           abort->ch.chunk_flags);
  			if (sctp_handle_nat_colliding_state(stcb)) {
  				return;
  			}
  		} else if (error == SCTP_CAUSE_NAT_MISSING_STATE) {
  			SCTPDBG(SCTP_DEBUG_INPUT2, "Received missing state abort flags:%x\n",
  			                           abort->ch.chunk_flags);
  			if (sctp_handle_nat_missing_state(stcb, net)) {
  				return;
  			}
  		}
  	} else {
  		error = 0;
  	}
  	/* stop any receive timers */
  	sctp_timer_stop(SCTP_TIMER_TYPE_RECV, stcb->sctp_ep, stcb, net,
  	                SCTP_FROM_SCTP_INPUT + SCTP_LOC_7);
  	/* notify user of the abort and clean up... */
  	sctp_abort_notification(stcb, 1, error, abort, SCTP_SO_NOT_LOCKED);
  	/* free the tcb */
  	SCTP_STAT_INCR_COUNTER32(sctps_aborted);
  	if ((SCTP_GET_STATE(&stcb->asoc) == SCTP_STATE_OPEN) ||
  	    (SCTP_GET_STATE(&stcb->asoc) == SCTP_STATE_SHUTDOWN_RECEIVED)) {
  		SCTP_STAT_DECR_GAUGE32(sctps_currestab);
  	}
  #ifdef SCTP_ASOCLOG_OF_TSNS
  	sctp_print_out_track_log(stcb);
  #endif
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  	so = SCTP_INP_SO(stcb->sctp_ep);
  	atomic_add_int(&stcb->asoc.refcnt, 1);
  	SCTP_TCB_UNLOCK(stcb);
  	SCTP_SOCKET_LOCK(so, 1);
  	SCTP_TCB_LOCK(stcb);
  	atomic_subtract_int(&stcb->asoc.refcnt, 1);
  #endif
  	stcb->asoc.state |= SCTP_STATE_WAS_ABORTED;
  	(void)sctp_free_assoc(stcb->sctp_ep, stcb, SCTP_NORMAL_PROC,
  			      SCTP_FROM_SCTP_INPUT + SCTP_LOC_8);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  	SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  	SCTPDBG(SCTP_DEBUG_INPUT2, "sctp_handle_abort: finished\n");
  }
  
  static void
  sctp_start_net_timers(struct sctp_tcb *stcb)
  {
  	uint32_t cnt_hb_sent;
  	struct sctp_nets *net;
  
  	cnt_hb_sent = 0;
  	TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) {
  		/* For each network start:
  		 * 1) A pmtu timer.
  		 * 2) A HB timer
  		 * 3) If the dest in unconfirmed send
  		 *    a hb as well if under max_hb_burst have
  		 *    been sent.
  		 */
  		sctp_timer_start(SCTP_TIMER_TYPE_PATHMTURAISE, stcb->sctp_ep, stcb, net);
  		sctp_timer_start(SCTP_TIMER_TYPE_HEARTBEAT, stcb->sctp_ep, stcb, net);
  		if ((net->dest_state & SCTP_ADDR_UNCONFIRMED) &&
  		    (cnt_hb_sent < SCTP_BASE_SYSCTL(sctp_hb_maxburst))) {
  			sctp_send_hb(stcb, net, SCTP_SO_NOT_LOCKED);
  			cnt_hb_sent++;
  		}
  	}
  	if (cnt_hb_sent) {
  		sctp_chunk_output(stcb->sctp_ep, stcb,
  				  SCTP_OUTPUT_FROM_COOKIE_ACK,
  				  SCTP_SO_NOT_LOCKED);
  	}
  }
  
  
  static void
  sctp_handle_shutdown(struct sctp_shutdown_chunk *cp,
      struct sctp_tcb *stcb, struct sctp_nets *net, int *abort_flag)
  {
  	struct sctp_association *asoc;
  	int some_on_streamwheel;
  	int old_state;
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  	struct socket *so;
  #endif
  
  	SCTPDBG(SCTP_DEBUG_INPUT2,
  		"sctp_handle_shutdown: handling SHUTDOWN\n");
  	if (stcb == NULL)
  		return;
  	asoc = &stcb->asoc;
  	if ((SCTP_GET_STATE(asoc) == SCTP_STATE_COOKIE_WAIT) ||
  	    (SCTP_GET_STATE(asoc) == SCTP_STATE_COOKIE_ECHOED)) {
  		return;
  	}
  	if (ntohs(cp->ch.chunk_length) != sizeof(struct sctp_shutdown_chunk)) {
  		/* Shutdown NOT the expected size */
  		return;
  	}
  	old_state = SCTP_GET_STATE(asoc);
  	sctp_update_acked(stcb, cp, abort_flag);
  	if (*abort_flag) {
  		return;
  	}
  	if (asoc->control_pdapi) {
  		/* With a normal shutdown
  		 * we assume the end of last record.
  		 */
  		SCTP_INP_READ_LOCK(stcb->sctp_ep);
  		if (asoc->control_pdapi->on_strm_q) {
  			struct sctp_stream_in *strm;
  
  			strm = &asoc->strmin[asoc->control_pdapi->sinfo_stream];
  			if (asoc->control_pdapi->on_strm_q == SCTP_ON_UNORDERED) {
  				/* Unordered */
  				TAILQ_REMOVE(&strm->uno_inqueue, asoc->control_pdapi, next_instrm);
  				asoc->control_pdapi->on_strm_q = 0;
  			} else if (asoc->control_pdapi->on_strm_q == SCTP_ON_ORDERED) {
  				/* Ordered */
  				TAILQ_REMOVE(&strm->inqueue, asoc->control_pdapi, next_instrm);
  				asoc->control_pdapi->on_strm_q = 0;
  #ifdef INVARIANTS
  			} else {
  				panic("Unknown state on ctrl:%p on_strm_q:%d",
  				      asoc->control_pdapi,
  				      asoc->control_pdapi->on_strm_q);
  #endif
  			}
  		}
  		asoc->control_pdapi->end_added = 1;
  		asoc->control_pdapi->pdapi_aborted = 1;
  		asoc->control_pdapi = NULL;
  		SCTP_INP_READ_UNLOCK(stcb->sctp_ep);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		so = SCTP_INP_SO(stcb->sctp_ep);
  		atomic_add_int(&stcb->asoc.refcnt, 1);
  		SCTP_TCB_UNLOCK(stcb);
  		SCTP_SOCKET_LOCK(so, 1);
  		SCTP_TCB_LOCK(stcb);
  		atomic_subtract_int(&stcb->asoc.refcnt, 1);
  		if (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET) {
  			/* assoc was freed while we were unlocked */
  			SCTP_SOCKET_UNLOCK(so, 1);
  			return;
  		}
  #endif
  		if (stcb->sctp_socket) {
  			sctp_sorwakeup(stcb->sctp_ep, stcb->sctp_socket);
  		}
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  	}
  	/* goto SHUTDOWN_RECEIVED state to block new requests */
  	if (stcb->sctp_socket) {
  		if ((SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_RECEIVED) &&
  		    (SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_ACK_SENT) &&
  		    (SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_SENT)) {
  			SCTP_SET_STATE(asoc, SCTP_STATE_SHUTDOWN_RECEIVED);
  			SCTP_CLEAR_SUBSTATE(asoc, SCTP_STATE_SHUTDOWN_PENDING);
  			/* notify upper layer that peer has initiated a shutdown */
  			sctp_ulp_notify(SCTP_NOTIFY_PEER_SHUTDOWN, stcb, 0, NULL, SCTP_SO_NOT_LOCKED);
  
  			/* reset time */
  			(void)SCTP_GETTIME_TIMEVAL(&asoc->time_entered);
  		}
  	}
  	if (SCTP_GET_STATE(asoc) == SCTP_STATE_SHUTDOWN_SENT) {
  		/*
  		 * stop the shutdown timer, since we WILL move to
  		 * SHUTDOWN-ACK-SENT.
  		 */
  		sctp_timer_stop(SCTP_TIMER_TYPE_SHUTDOWN, stcb->sctp_ep, stcb,
  		                net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_9);
  	}
  	/* Now is there unsent data on a stream somewhere? */
  	some_on_streamwheel = sctp_is_there_unsent_data(stcb, SCTP_SO_NOT_LOCKED);
  
  	if (!TAILQ_EMPTY(&asoc->send_queue) ||
  	    !TAILQ_EMPTY(&asoc->sent_queue) ||
  	    some_on_streamwheel) {
  		/* By returning we will push more data out */
  		return;
  	} else {
  		/* no outstanding data to send, so move on... */
  		/* send SHUTDOWN-ACK */
  		/* move to SHUTDOWN-ACK-SENT state */
  		if ((SCTP_GET_STATE(asoc) == SCTP_STATE_OPEN) ||
  		    (SCTP_GET_STATE(asoc) == SCTP_STATE_SHUTDOWN_RECEIVED)) {
  			SCTP_STAT_DECR_GAUGE32(sctps_currestab);
  		}
  		SCTP_CLEAR_SUBSTATE(asoc, SCTP_STATE_SHUTDOWN_PENDING);
  		if (SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_ACK_SENT) {
  			SCTP_SET_STATE(asoc, SCTP_STATE_SHUTDOWN_ACK_SENT);
  			sctp_stop_timers_for_shutdown(stcb);
  			sctp_send_shutdown_ack(stcb, net);
  			sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNACK,
  			                 stcb->sctp_ep, stcb, net);
  		} else if (old_state == SCTP_STATE_SHUTDOWN_ACK_SENT) {
  			sctp_send_shutdown_ack(stcb, net);
  		}
  	}
  }
  
  static void
  sctp_handle_shutdown_ack(struct sctp_shutdown_ack_chunk *cp SCTP_UNUSED,
                           struct sctp_tcb *stcb,
                           struct sctp_nets *net)
  {
  	struct sctp_association *asoc;
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  	struct socket *so;
  
  	so = SCTP_INP_SO(stcb->sctp_ep);
  #endif
  	SCTPDBG(SCTP_DEBUG_INPUT2,
  		"sctp_handle_shutdown_ack: handling SHUTDOWN ACK\n");
  	if (stcb == NULL)
  		return;
  
  	asoc = &stcb->asoc;
  	/* process according to association state */
  	if ((SCTP_GET_STATE(asoc) == SCTP_STATE_COOKIE_WAIT) ||
  	    (SCTP_GET_STATE(asoc) == SCTP_STATE_COOKIE_ECHOED)) {
  		/* unexpected SHUTDOWN-ACK... do OOTB handling... */
  		sctp_send_shutdown_complete(stcb, net, 1);
  		SCTP_TCB_UNLOCK(stcb);
  		return;
  	}
  	if ((SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_SENT) &&
  	    (SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_ACK_SENT)) {
  		/* unexpected SHUTDOWN-ACK... so ignore... */
  		SCTP_TCB_UNLOCK(stcb);
  		return;
  	}
  	if (asoc->control_pdapi) {
  		/* With a normal shutdown
  		 * we assume the end of last record.
  		 */
  		SCTP_INP_READ_LOCK(stcb->sctp_ep);
  		asoc->control_pdapi->end_added = 1;
  		asoc->control_pdapi->pdapi_aborted = 1;
  		asoc->control_pdapi = NULL;
  		SCTP_INP_READ_UNLOCK(stcb->sctp_ep);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		atomic_add_int(&stcb->asoc.refcnt, 1);
  		SCTP_TCB_UNLOCK(stcb);
  		SCTP_SOCKET_LOCK(so, 1);
  		SCTP_TCB_LOCK(stcb);
  		atomic_subtract_int(&stcb->asoc.refcnt, 1);
  		if (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET) {
  			/* assoc was freed while we were unlocked */
  			SCTP_SOCKET_UNLOCK(so, 1);
  			return;
  		}
  #endif
  		sctp_sorwakeup(stcb->sctp_ep, stcb->sctp_socket);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  	}
  #ifdef INVARIANTS
  	if (!TAILQ_EMPTY(&asoc->send_queue) ||
  	    !TAILQ_EMPTY(&asoc->sent_queue) ||
  	    !stcb->asoc.ss_functions.sctp_ss_is_empty(stcb, asoc)) {
  		panic("Queues are not empty when handling SHUTDOWN-ACK");
  	}
  #endif
  	/* stop the timer */
  	sctp_timer_stop(SCTP_TIMER_TYPE_SHUTDOWN, stcb->sctp_ep, stcb, net,
  	                SCTP_FROM_SCTP_INPUT + SCTP_LOC_10);
  	/* send SHUTDOWN-COMPLETE */
  	sctp_send_shutdown_complete(stcb, net, 0);
  	/* notify upper layer protocol */
  	if (stcb->sctp_socket) {
  		if ((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) ||
  		    (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_IN_TCPPOOL)) {
  			stcb->sctp_socket->so_snd.sb_cc = 0;
  		}
  		sctp_ulp_notify(SCTP_NOTIFY_ASSOC_DOWN, stcb, 0, NULL, SCTP_SO_NOT_LOCKED);
  	}
  	SCTP_STAT_INCR_COUNTER32(sctps_shutdown);
  	/* free the TCB but first save off the ep */
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  	atomic_add_int(&stcb->asoc.refcnt, 1);
  	SCTP_TCB_UNLOCK(stcb);
  	SCTP_SOCKET_LOCK(so, 1);
  	SCTP_TCB_LOCK(stcb);
  	atomic_subtract_int(&stcb->asoc.refcnt, 1);
  #endif
  	(void)sctp_free_assoc(stcb->sctp_ep, stcb, SCTP_NORMAL_PROC,
  			      SCTP_FROM_SCTP_INPUT + SCTP_LOC_11);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  	SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  }
  
  /*
   * Skip past the param header and then we will find the chunk that caused the
   * problem. There are two possibilities ASCONF or FWD-TSN other than that and
   * our peer must be broken.
   */
  static void
  sctp_process_unrecog_chunk(struct sctp_tcb *stcb, struct sctp_paramhdr *phdr,
      struct sctp_nets *net)
  {
  	struct sctp_chunkhdr *chk;
  
  	chk = (struct sctp_chunkhdr *)((caddr_t)phdr + sizeof(*phdr));
  	switch (chk->chunk_type) {
  	case SCTP_ASCONF_ACK:
  	case SCTP_ASCONF:
  		sctp_asconf_cleanup(stcb, net);
  		break;
  	case SCTP_IFORWARD_CUM_TSN:
  	case SCTP_FORWARD_CUM_TSN:
  		stcb->asoc.prsctp_supported = 0;
  		break;
  	default:
  		SCTPDBG(SCTP_DEBUG_INPUT2,
  			"Peer does not support chunk type %d(%x)??\n",
  			chk->chunk_type, (uint32_t) chk->chunk_type);
  		break;
  	}
  }
  
  /*
   * Skip past the param header and then we will find the param that caused the
   * problem.  There are a number of param's in a ASCONF OR the prsctp param
   * these will turn of specific features.
   * XXX: Is this the right thing to do?
   */
  static void
  sctp_process_unrecog_param(struct sctp_tcb *stcb, struct sctp_paramhdr *phdr)
  {
  	struct sctp_paramhdr *pbad;
  
  	pbad = phdr + 1;
  	switch (ntohs(pbad->param_type)) {
  		/* pr-sctp draft */
  	case SCTP_PRSCTP_SUPPORTED:
  		stcb->asoc.prsctp_supported = 0;
  		break;
  	case SCTP_SUPPORTED_CHUNK_EXT:
  		break;
  		/* draft-ietf-tsvwg-addip-sctp */
  	case SCTP_HAS_NAT_SUPPORT:
  	        stcb->asoc.peer_supports_nat = 0;
  	        break;
  	case SCTP_ADD_IP_ADDRESS:
  	case SCTP_DEL_IP_ADDRESS:
  	case SCTP_SET_PRIM_ADDR:
  		stcb->asoc.asconf_supported = 0;
  		break;
  	case SCTP_SUCCESS_REPORT:
  	case SCTP_ERROR_CAUSE_IND:
  		SCTPDBG(SCTP_DEBUG_INPUT2, "Huh, the peer does not support success? or error cause?\n");
  		SCTPDBG(SCTP_DEBUG_INPUT2,
  			"Turning off ASCONF to this strange peer\n");
  		stcb->asoc.asconf_supported = 0;
  		break;
  	default:
  		SCTPDBG(SCTP_DEBUG_INPUT2,
  			"Peer does not support param type %d(%x)??\n",
  			pbad->param_type, (uint32_t) pbad->param_type);
  		break;
  	}
  }
  
  static int
  sctp_handle_error(struct sctp_chunkhdr *ch,
      struct sctp_tcb *stcb, struct sctp_nets *net)
  {
  	int chklen;
  	struct sctp_paramhdr *phdr;
  	uint16_t error, error_type;
  	uint16_t error_len;
  	struct sctp_association *asoc;
  	int adjust;
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  	struct socket *so;
  #endif
  
  	/* parse through all of the errors and process */
  	asoc = &stcb->asoc;
  	phdr = (struct sctp_paramhdr *)((caddr_t)ch +
  	    sizeof(struct sctp_chunkhdr));
  	chklen = ntohs(ch->chunk_length) - sizeof(struct sctp_chunkhdr);
  	error = 0;
  	while ((size_t)chklen >= sizeof(struct sctp_paramhdr)) {
  		/* Process an Error Cause */
  		error_type = ntohs(phdr->param_type);
  		error_len = ntohs(phdr->param_length);
  		if ((error_len > chklen) || (error_len == 0)) {
  			/* invalid param length for this param */
  			SCTPDBG(SCTP_DEBUG_INPUT1, "Bogus length in error param- chunk left:%d errorlen:%d\n",
  				chklen, error_len);
  			return (0);
  		}
  		if (error == 0) {
  			/* report the first error cause */
  			error = error_type;
  		}
  		switch (error_type) {
  		case SCTP_CAUSE_INVALID_STREAM:
  		case SCTP_CAUSE_MISSING_PARAM:
  		case SCTP_CAUSE_INVALID_PARAM:
  		case SCTP_CAUSE_NO_USER_DATA:
  			SCTPDBG(SCTP_DEBUG_INPUT1, "Software error we got a %d back? We have a bug :/ (or do they?)\n",
  				error_type);
  			break;
  		case SCTP_CAUSE_NAT_COLLIDING_STATE:
  		        SCTPDBG(SCTP_DEBUG_INPUT2, "Received Colliding state abort flags:%x\n",
  				ch->chunk_flags);
  			if (sctp_handle_nat_colliding_state(stcb)) {
  			  return (0);
  			}
  			break;
  		case SCTP_CAUSE_NAT_MISSING_STATE:
  			SCTPDBG(SCTP_DEBUG_INPUT2, "Received missing state abort flags:%x\n",
  			                           ch->chunk_flags);
  			if (sctp_handle_nat_missing_state(stcb, net)) {
  			  return (0);
  			}
  			break;
  		case SCTP_CAUSE_STALE_COOKIE:
  			/*
  			 * We only act if we have echoed a cookie and are
  			 * waiting.
  			 */
  			if (SCTP_GET_STATE(asoc) == SCTP_STATE_COOKIE_ECHOED) {
  				int *p;
  
  				p = (int *)((caddr_t)phdr + sizeof(*phdr));
  				/* Save the time doubled */
  				asoc->cookie_preserve_req = ntohl(*p) << 1;
  				asoc->stale_cookie_count++;
  				if (asoc->stale_cookie_count >
  				    asoc->max_init_times) {
  					sctp_abort_notification(stcb, 0, 0, NULL, SCTP_SO_NOT_LOCKED);
  					/* now free the asoc */
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  					so = SCTP_INP_SO(stcb->sctp_ep);
  					atomic_add_int(&stcb->asoc.refcnt, 1);
  					SCTP_TCB_UNLOCK(stcb);
  					SCTP_SOCKET_LOCK(so, 1);
  					SCTP_TCB_LOCK(stcb);
  					atomic_subtract_int(&stcb->asoc.refcnt, 1);
  #endif
  					(void)sctp_free_assoc(stcb->sctp_ep, stcb, SCTP_NORMAL_PROC,
  							      SCTP_FROM_SCTP_INPUT + SCTP_LOC_12);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  					SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  					return (-1);
  				}
  				/* blast back to INIT state */
  				sctp_toss_old_cookies(stcb, &stcb->asoc);
  				asoc->state &= ~SCTP_STATE_COOKIE_ECHOED;
  				asoc->state |= SCTP_STATE_COOKIE_WAIT;
  				sctp_stop_all_cookie_timers(stcb);
  				sctp_send_initiate(stcb->sctp_ep, stcb, SCTP_SO_NOT_LOCKED);
  			}
  			break;
  		case SCTP_CAUSE_UNRESOLVABLE_ADDR:
  			/*
  			 * Nothing we can do here, we don't do hostname
  			 * addresses so if the peer does not like my IPv6
  			 * (or IPv4 for that matter) it does not matter. If
  			 * they don't support that type of address, they can
  			 * NOT possibly get that packet type... i.e. with no
  			 * IPv6 you can't receive a IPv6 packet. so we can
  			 * safely ignore this one. If we ever added support
  			 * for HOSTNAME Addresses, then we would need to do
  			 * something here.
  			 */
  			break;
  		case SCTP_CAUSE_UNRECOG_CHUNK:
  			sctp_process_unrecog_chunk(stcb, phdr, net);
  			break;
  		case SCTP_CAUSE_UNRECOG_PARAM:
  			sctp_process_unrecog_param(stcb, phdr);
  			break;
  		case SCTP_CAUSE_COOKIE_IN_SHUTDOWN:
  			/*
  			 * We ignore this since the timer will drive out a
  			 * new cookie anyway and there timer will drive us
  			 * to send a SHUTDOWN_COMPLETE. We can't send one
  			 * here since we don't have their tag.
  			 */
  			break;
  		case SCTP_CAUSE_DELETING_LAST_ADDR:
  		case SCTP_CAUSE_RESOURCE_SHORTAGE:
  		case SCTP_CAUSE_DELETING_SRC_ADDR:
  			/*
  			 * We should NOT get these here, but in a
  			 * ASCONF-ACK.
  			 */
  			SCTPDBG(SCTP_DEBUG_INPUT2, "Peer sends ASCONF errors in a Operational Error?<%d>?\n",
  				error_type);
  			break;
  		case SCTP_CAUSE_OUT_OF_RESC:
  			/*
  			 * And what, pray tell do we do with the fact that
  			 * the peer is out of resources? Not really sure we
  			 * could do anything but abort. I suspect this
  			 * should have came WITH an abort instead of in a
  			 * OP-ERROR.
  			 */
  			break;
  		default:
  			SCTPDBG(SCTP_DEBUG_INPUT1, "sctp_handle_error: unknown error type = 0x%xh\n",
  				error_type);
  			break;
  		}
  		adjust = SCTP_SIZE32(error_len);
  		chklen -= adjust;
  		phdr = (struct sctp_paramhdr *)((caddr_t)phdr + adjust);
  	}
  	sctp_ulp_notify(SCTP_NOTIFY_REMOTE_ERROR, stcb, error, ch, SCTP_SO_NOT_LOCKED);
  	return (0);
  }
  
  static int
  sctp_handle_init_ack(struct mbuf *m, int iphlen, int offset,
                       struct sockaddr *src, struct sockaddr *dst, struct sctphdr *sh,
                       struct sctp_init_ack_chunk *cp, struct sctp_tcb *stcb,
                       struct sctp_nets *net, int *abort_no_unlock,
  #if defined(__FreeBSD__)
                       uint8_t mflowtype, uint32_t mflowid,
  #endif
                       uint32_t vrf_id)
  {
  	struct sctp_init_ack *init_ack;
  	struct mbuf *op_err;
  
  	SCTPDBG(SCTP_DEBUG_INPUT2,
  		"sctp_handle_init_ack: handling INIT-ACK\n");
  
  	if (stcb == NULL) {
  		SCTPDBG(SCTP_DEBUG_INPUT2,
  			"sctp_handle_init_ack: TCB is null\n");
  		return (-1);
  	}
  	if (ntohs(cp->ch.chunk_length) < sizeof(struct sctp_init_ack_chunk)) {
  		/* Invalid length */
  		op_err = sctp_generate_cause(SCTP_CAUSE_INVALID_PARAM, "");
  		sctp_abort_association(stcb->sctp_ep, stcb, m, iphlen,
  		                       src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  		                       mflowtype, mflowid,
  #endif
  		                       vrf_id, net->port);
  		*abort_no_unlock = 1;
  		return (-1);
  	}
  	init_ack = &cp->init;
  	/* validate parameters */
  	if (init_ack->initiate_tag == 0) {
  		/* protocol error... send an abort */
  		op_err = sctp_generate_cause(SCTP_CAUSE_INVALID_PARAM, "");
  		sctp_abort_association(stcb->sctp_ep, stcb, m, iphlen,
  		                       src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  		                       mflowtype, mflowid,
  #endif
  		                       vrf_id, net->port);
  		*abort_no_unlock = 1;
  		return (-1);
  	}
  	if (ntohl(init_ack->a_rwnd) < SCTP_MIN_RWND) {
  		/* protocol error... send an abort */
  		op_err = sctp_generate_cause(SCTP_CAUSE_INVALID_PARAM, "");
  		sctp_abort_association(stcb->sctp_ep, stcb, m, iphlen,
  		                       src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  		                       mflowtype, mflowid,
  #endif
  		                       vrf_id, net->port);
  		*abort_no_unlock = 1;
  		return (-1);
  	}
  	if (init_ack->num_inbound_streams == 0) {
  		/* protocol error... send an abort */
  		op_err = sctp_generate_cause(SCTP_CAUSE_INVALID_PARAM, "");
  		sctp_abort_association(stcb->sctp_ep, stcb, m, iphlen,
  		                       src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  		                       mflowtype, mflowid,
  #endif
  		                       vrf_id, net->port);
  		*abort_no_unlock = 1;
  		return (-1);
  	}
  	if (init_ack->num_outbound_streams == 0) {
  		/* protocol error... send an abort */
  		op_err = sctp_generate_cause(SCTP_CAUSE_INVALID_PARAM, "");
  		sctp_abort_association(stcb->sctp_ep, stcb, m, iphlen,
  		                       src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  		                       mflowtype, mflowid,
  #endif
  		                       vrf_id, net->port);
  		*abort_no_unlock = 1;
  		return (-1);
  	}
  	/* process according to association state... */
  	switch (stcb->asoc.state & SCTP_STATE_MASK) {
  	case SCTP_STATE_COOKIE_WAIT:
  		/* this is the expected state for this chunk */
  		/* process the INIT-ACK parameters */
  		if (stcb->asoc.primary_destination->dest_state &
  		    SCTP_ADDR_UNCONFIRMED) {
  			/*
  			 * The primary is where we sent the INIT, we can
  			 * always consider it confirmed when the INIT-ACK is
  			 * returned. Do this before we load addresses
  			 * though.
  			 */
  			stcb->asoc.primary_destination->dest_state &=
  			    ~SCTP_ADDR_UNCONFIRMED;
  			sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_CONFIRMED,
  			    stcb, 0, (void *)stcb->asoc.primary_destination, SCTP_SO_NOT_LOCKED);
  		}
  		if (sctp_process_init_ack(m, iphlen, offset, src, dst, sh, cp, stcb,
  		                          net, abort_no_unlock,
  #if defined(__FreeBSD__)
  		                          mflowtype, mflowid,
  #endif
  		                          vrf_id) < 0) {
  			/* error in parsing parameters */
  			return (-1);
  		}
  		/* update our state */
  		SCTPDBG(SCTP_DEBUG_INPUT2, "moving to COOKIE-ECHOED state\n");
  		SCTP_SET_STATE(&stcb->asoc, SCTP_STATE_COOKIE_ECHOED);
  
  		/* reset the RTO calc */
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
  			sctp_misc_ints(SCTP_THRESHOLD_CLEAR,
  				       stcb->asoc.overall_error_count,
  				       0,
  				       SCTP_FROM_SCTP_INPUT,
  				       __LINE__);
  		}
  		stcb->asoc.overall_error_count = 0;
  		(void)SCTP_GETTIME_TIMEVAL(&stcb->asoc.time_entered);
  		/*
  		 * collapse the init timer back in case of a exponential
  		 * backoff
  		 */
  		sctp_timer_start(SCTP_TIMER_TYPE_COOKIE, stcb->sctp_ep,
  		    stcb, net);
  		/*
  		 * the send at the end of the inbound data processing will
  		 * cause the cookie to be sent
  		 */
  		break;
  	case SCTP_STATE_SHUTDOWN_SENT:
  		/* incorrect state... discard */
  		break;
  	case SCTP_STATE_COOKIE_ECHOED:
  		/* incorrect state... discard */
  		break;
  	case SCTP_STATE_OPEN:
  		/* incorrect state... discard */
  		break;
  	case SCTP_STATE_EMPTY:
  	case SCTP_STATE_INUSE:
  	default:
  		/* incorrect state... discard */
  		return (-1);
  		break;
  	}
  	SCTPDBG(SCTP_DEBUG_INPUT1, "Leaving handle-init-ack end\n");
  	return (0);
  }
  
  static struct sctp_tcb *
  sctp_process_cookie_new(struct mbuf *m, int iphlen, int offset,
      struct sockaddr *src, struct sockaddr *dst,
      struct sctphdr *sh, struct sctp_state_cookie *cookie, int cookie_len,
      struct sctp_inpcb *inp, struct sctp_nets **netp,
      struct sockaddr *init_src, int *notification,
      int auth_skipped, uint32_t auth_offset, uint32_t auth_len,
  #if defined(__FreeBSD__)
      uint8_t mflowtype, uint32_t mflowid,
  #endif
      uint32_t vrf_id, uint16_t port);
  
  
  /*
   * handle a state cookie for an existing association m: input packet mbuf
   * chain-- assumes a pullup on IP/SCTP/COOKIE-ECHO chunk note: this is a
   * "split" mbuf and the cookie signature does not exist offset: offset into
   * mbuf to the cookie-echo chunk
   */
  static struct sctp_tcb *
  sctp_process_cookie_existing(struct mbuf *m, int iphlen, int offset,
      struct sockaddr *src, struct sockaddr *dst,
      struct sctphdr *sh, struct sctp_state_cookie *cookie, int cookie_len,
      struct sctp_inpcb *inp, struct sctp_tcb *stcb, struct sctp_nets **netp,
      struct sockaddr *init_src, int *notification,
      int auth_skipped, uint32_t auth_offset, uint32_t auth_len,
  #if defined(__FreeBSD__)
      uint8_t mflowtype, uint32_t mflowid,
  #endif
      uint32_t vrf_id, uint16_t port)
  {
  	struct sctp_association *asoc;
  	struct sctp_init_chunk *init_cp, init_buf;
  	struct sctp_init_ack_chunk *initack_cp, initack_buf;
  	struct sctp_nets *net;
  	struct mbuf *op_err;
  	int init_offset, initack_offset, i;
  	int retval;
  	int spec_flag = 0;
  	uint32_t how_indx;
  #if defined(SCTP_DETAILED_STR_STATS)
  	int j;
  #endif
  
  	net = *netp;
  	/* I know that the TCB is non-NULL from the caller */
  	asoc = &stcb->asoc;
  	for (how_indx = 0; how_indx  < sizeof(asoc->cookie_how); how_indx++) {
  		if (asoc->cookie_how[how_indx] == 0)
  			break;
  	}
  	if (how_indx < sizeof(asoc->cookie_how)) {
  		asoc->cookie_how[how_indx] = 1;
  	}
  	if (SCTP_GET_STATE(asoc) == SCTP_STATE_SHUTDOWN_ACK_SENT) {
  		/* SHUTDOWN came in after sending INIT-ACK */
  		sctp_send_shutdown_ack(stcb, stcb->asoc.primary_destination);
  		op_err = sctp_generate_cause(SCTP_CAUSE_COOKIE_IN_SHUTDOWN, "");
  		sctp_send_operr_to(src, dst, sh, cookie->peers_vtag, op_err,
  #if defined(__FreeBSD__)
  		                   mflowtype, mflowid, inp->fibnum,
  #endif
  		                   vrf_id, net->port);
  		if (how_indx < sizeof(asoc->cookie_how))
  			asoc->cookie_how[how_indx] = 2;
  		return (NULL);
  	}
  	/*
  	 * find and validate the INIT chunk in the cookie (peer's info) the
  	 * INIT should start after the cookie-echo header struct (chunk
  	 * header, state cookie header struct)
  	 */
  	init_offset = offset += sizeof(struct sctp_cookie_echo_chunk);
  
  	init_cp = (struct sctp_init_chunk *)
  		sctp_m_getptr(m, init_offset, sizeof(struct sctp_init_chunk),
  			      (uint8_t *) & init_buf);
  	if (init_cp == NULL) {
  		/* could not pull a INIT chunk in cookie */
  		return (NULL);
  	}
  	if (init_cp->ch.chunk_type != SCTP_INITIATION) {
  		return (NULL);
  	}
  	/*
  	 * find and validate the INIT-ACK chunk in the cookie (my info) the
  	 * INIT-ACK follows the INIT chunk
  	 */
  	initack_offset = init_offset + SCTP_SIZE32(ntohs(init_cp->ch.chunk_length));
  	initack_cp = (struct sctp_init_ack_chunk *)
  		sctp_m_getptr(m, initack_offset, sizeof(struct sctp_init_ack_chunk),
  			      (uint8_t *) & initack_buf);
  	if (initack_cp == NULL) {
  		/* could not pull INIT-ACK chunk in cookie */
  		return (NULL);
  	}
  	if (initack_cp->ch.chunk_type != SCTP_INITIATION_ACK) {
  		return (NULL);
  	}
  	if ((ntohl(initack_cp->init.initiate_tag) == asoc->my_vtag) &&
  	    (ntohl(init_cp->init.initiate_tag) == asoc->peer_vtag)) {
  		/*
  		 * case D in Section 5.2.4 Table 2: MMAA process accordingly
  		 * to get into the OPEN state
  		 */
  		if (ntohl(initack_cp->init.initial_tsn) != asoc->init_seq_number) {
  			/*-
  			 * Opps, this means that we somehow generated two vtag's
  			 * the same. I.e. we did:
  			 *  Us               Peer
  			 *   <---INIT(tag=a)------
  			 *   ----INIT-ACK(tag=t)-->
  			 *   ----INIT(tag=t)------> *1
  			 *   <---INIT-ACK(tag=a)---
                           *   <----CE(tag=t)------------- *2
  			 *
  			 * At point *1 we should be generating a different
  			 * tag t'. Which means we would throw away the CE and send
  			 * ours instead. Basically this is case C (throw away side).
  			 */
  			if (how_indx < sizeof(asoc->cookie_how))
  				asoc->cookie_how[how_indx] = 17;
  			return (NULL);
  
  		}
  		switch (SCTP_GET_STATE(asoc)) {
  			case SCTP_STATE_COOKIE_WAIT:
  			case SCTP_STATE_COOKIE_ECHOED:
  				/*
  				 * INIT was sent but got a COOKIE_ECHO with the
  				 * correct tags... just accept it...but we must
  				 * process the init so that we can make sure we
  				 * have the right seq no's.
  				 */
  				/* First we must process the INIT !! */
  				retval = sctp_process_init(init_cp, stcb);
  				if (retval < 0) {
  					if (how_indx < sizeof(asoc->cookie_how))
  						asoc->cookie_how[how_indx] = 3;
  					return (NULL);
  				}
  				/* we have already processed the INIT so no problem */
  				sctp_timer_stop(SCTP_TIMER_TYPE_HEARTBEAT, inp,
  				                stcb, net,
  				                SCTP_FROM_SCTP_INPUT + SCTP_LOC_13);
  				sctp_timer_stop(SCTP_TIMER_TYPE_INIT, inp,
  				                stcb, net,
  				                SCTP_FROM_SCTP_INPUT + SCTP_LOC_14);
  				/* update current state */
  				if (SCTP_GET_STATE(asoc) == SCTP_STATE_COOKIE_ECHOED)
  					SCTP_STAT_INCR_COUNTER32(sctps_activeestab);
  				else
  					SCTP_STAT_INCR_COUNTER32(sctps_collisionestab);
  
  				SCTP_SET_STATE(asoc, SCTP_STATE_OPEN);
  				if (asoc->state & SCTP_STATE_SHUTDOWN_PENDING) {
  					sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
  							 stcb->sctp_ep, stcb, asoc->primary_destination);
  				}
  				SCTP_STAT_INCR_GAUGE32(sctps_currestab);
  				sctp_stop_all_cookie_timers(stcb);
  				if (((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) ||
  				     (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_IN_TCPPOOL)) &&
  				    (inp->sctp_socket->so_qlimit == 0)
  					) {
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  					struct socket *so;
  #endif
  					/*
  					 * Here is where collision would go if we
  					 * did a connect() and instead got a
  					 * init/init-ack/cookie done before the
  					 * init-ack came back..
  					 */
  					stcb->sctp_ep->sctp_flags |=
  						SCTP_PCB_FLAGS_CONNECTED;
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  					so = SCTP_INP_SO(stcb->sctp_ep);
  					atomic_add_int(&stcb->asoc.refcnt, 1);
  					SCTP_TCB_UNLOCK(stcb);
  					SCTP_SOCKET_LOCK(so, 1);
  					SCTP_TCB_LOCK(stcb);
  					atomic_add_int(&stcb->asoc.refcnt, -1);
  					if (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET) {
  						SCTP_SOCKET_UNLOCK(so, 1);
  						return (NULL);
  					}
  #endif
  					soisconnected(stcb->sctp_socket);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  					SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  				}
  				/* notify upper layer */
  				*notification = SCTP_NOTIFY_ASSOC_UP;
  				/*
  				 * since we did not send a HB make sure we
  				 * don't double things
  				 */
  				net->hb_responded = 1;
  				net->RTO = sctp_calculate_rto(stcb, asoc, net,
  							      &cookie->time_entered,
  							      sctp_align_unsafe_makecopy,
  							      SCTP_RTT_FROM_NON_DATA);
  
  				if (stcb->asoc.sctp_autoclose_ticks &&
  				    (sctp_is_feature_on(inp, SCTP_PCB_FLAGS_AUTOCLOSE))) {
  					sctp_timer_start(SCTP_TIMER_TYPE_AUTOCLOSE,
  							 inp, stcb, NULL);
  				}
  				break;
  			default:
  				/*
  				 * we're in the OPEN state (or beyond), so
  				 * peer must have simply lost the COOKIE-ACK
  				 */
  				break;
  		}	/* end switch */
  		sctp_stop_all_cookie_timers(stcb);
  		/*
  		 * We ignore the return code here.. not sure if we should
  		 * somehow abort.. but we do have an existing asoc. This
  		 * really should not fail.
  		 */
  		if (sctp_load_addresses_from_init(stcb, m,
  						  init_offset + sizeof(struct sctp_init_chunk),
  						  initack_offset, src, dst, init_src, stcb->asoc.port)) {
  			if (how_indx < sizeof(asoc->cookie_how))
  				asoc->cookie_how[how_indx] = 4;
  			return (NULL);
  		}
  		/* respond with a COOKIE-ACK */
  		sctp_toss_old_cookies(stcb, asoc);
  		sctp_send_cookie_ack(stcb);
  		if (how_indx < sizeof(asoc->cookie_how))
  			asoc->cookie_how[how_indx] = 5;
  		return (stcb);
  	}
  
  	if (ntohl(initack_cp->init.initiate_tag) != asoc->my_vtag &&
  	    ntohl(init_cp->init.initiate_tag) == asoc->peer_vtag &&
  	    cookie->tie_tag_my_vtag == 0 &&
  	    cookie->tie_tag_peer_vtag == 0) {
  		/*
  		 * case C in Section 5.2.4 Table 2: XMOO silently discard
  		 */
  		if (how_indx < sizeof(asoc->cookie_how))
  			asoc->cookie_how[how_indx] = 6;
  		return (NULL);
  	}
  	/* If nat support, and the below and stcb is established,
  	 * send back a ABORT(colliding state) if we are established.
  	 */
  	if ((SCTP_GET_STATE(asoc) == SCTP_STATE_OPEN)  &&
  	    (asoc->peer_supports_nat) &&
  	    ((ntohl(initack_cp->init.initiate_tag) == asoc->my_vtag) &&
  	    ((ntohl(init_cp->init.initiate_tag) != asoc->peer_vtag) ||
  	     (asoc->peer_vtag == 0)))) {
  		/* Special case - Peer's support nat. We may have
  		 * two init's that we gave out the same tag on since
  		 * one was not established.. i.e. we get INIT from host-1
  		 * behind the nat and we respond tag-a, we get a INIT from
  		 * host-2 behind the nat and we get tag-a again. Then we
  		 * bring up host-1 (or 2's) assoc, Then comes the cookie
  		 * from hsot-2 (or 1). Now we have colliding state. We must
  		 * send an abort here with colliding state indication.
  		 */
  		op_err = sctp_generate_cause(SCTP_CAUSE_NAT_COLLIDING_STATE, "");
  		sctp_send_abort(m, iphlen,  src, dst, sh, 0, op_err,
  #if defined(__FreeBSD__)
  		                mflowtype, mflowid, inp->fibnum,
  #endif
  		                vrf_id, port);
  		return (NULL);
  	}
  	if ((ntohl(initack_cp->init.initiate_tag) == asoc->my_vtag) &&
  	    ((ntohl(init_cp->init.initiate_tag) != asoc->peer_vtag) ||
  	     (asoc->peer_vtag == 0))) {
  		/*
  		 * case B in Section 5.2.4 Table 2: MXAA or MOAA my info
  		 * should be ok, re-accept peer info
  		 */
  		if (ntohl(initack_cp->init.initial_tsn) != asoc->init_seq_number) {
  			/* Extension of case C.
  			 * If we hit this, then the random number
  			 * generator returned the same vtag when we
  			 * first sent our INIT-ACK and when we later sent
  			 * our INIT. The side with the seq numbers that are
  			 * different will be the one that normnally would
  			 * have hit case C. This in effect "extends" our vtags
  			 * in this collision case to be 64 bits. The same collision
  			 * could occur aka you get both vtag and seq number the
  			 * same twice in a row.. but is much less likely. If it
  			 * did happen then we would proceed through and bring
  			 * up the assoc.. we may end up with the wrong stream
  			 * setup however.. which would be bad.. but there is
  			 * no way to tell.. until we send on a stream that does
  			 * not exist :-)
  			 */
  			if (how_indx < sizeof(asoc->cookie_how))
  				asoc->cookie_how[how_indx] = 7;
  
  			return (NULL);
  		}
  		if (how_indx < sizeof(asoc->cookie_how))
  			asoc->cookie_how[how_indx] = 8;
  		sctp_timer_stop(SCTP_TIMER_TYPE_HEARTBEAT, inp, stcb, net,
  		                SCTP_FROM_SCTP_INPUT + SCTP_LOC_15);
  		sctp_stop_all_cookie_timers(stcb);
  		/*
  		 * since we did not send a HB make sure we don't double
  		 * things
  		 */
  		net->hb_responded = 1;
  		if (stcb->asoc.sctp_autoclose_ticks &&
  		    sctp_is_feature_on(inp, SCTP_PCB_FLAGS_AUTOCLOSE)) {
  			sctp_timer_start(SCTP_TIMER_TYPE_AUTOCLOSE, inp, stcb,
  					 NULL);
  		}
  		asoc->my_rwnd = ntohl(initack_cp->init.a_rwnd);
  		asoc->pre_open_streams = ntohs(initack_cp->init.num_outbound_streams);
  
  		if (ntohl(init_cp->init.initiate_tag) != asoc->peer_vtag) {
  			/* Ok the peer probably discarded our
  			 * data (if we echoed a cookie+data). So anything
  			 * on the sent_queue should be marked for
  			 * retransmit, we may not get something to
  			 * kick us so it COULD still take a timeout
  			 * to move these.. but it can't hurt to mark them.
  			 */
  			struct sctp_tmit_chunk *chk;
  		        TAILQ_FOREACH(chk, &stcb->asoc.sent_queue, sctp_next) {
  				if (chk->sent < SCTP_DATAGRAM_RESEND) {
  					chk->sent = SCTP_DATAGRAM_RESEND;
  					sctp_flight_size_decrease(chk);
  					sctp_total_flight_decrease(stcb, chk);
  					sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
  					spec_flag++;
  				}
  			}
  
  		}
  		/* process the INIT info (peer's info) */
  		retval = sctp_process_init(init_cp, stcb);
  		if (retval < 0) {
  			if (how_indx < sizeof(asoc->cookie_how))
  				asoc->cookie_how[how_indx] = 9;
  			return (NULL);
  		}
  		if (sctp_load_addresses_from_init(stcb, m,
  						  init_offset + sizeof(struct sctp_init_chunk),
  						  initack_offset, src, dst, init_src, stcb->asoc.port)) {
  			if (how_indx < sizeof(asoc->cookie_how))
  				asoc->cookie_how[how_indx] = 10;
  			return (NULL);
  		}
  		if ((asoc->state & SCTP_STATE_COOKIE_WAIT) ||
  		    (asoc->state & SCTP_STATE_COOKIE_ECHOED)) {
  			*notification = SCTP_NOTIFY_ASSOC_UP;
  
  			if (((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) ||
  			     (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_IN_TCPPOOL)) &&
  			    (inp->sctp_socket->so_qlimit == 0)) {
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  				struct socket *so;
  #endif
  				stcb->sctp_ep->sctp_flags |=
  					SCTP_PCB_FLAGS_CONNECTED;
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  				so = SCTP_INP_SO(stcb->sctp_ep);
  				atomic_add_int(&stcb->asoc.refcnt, 1);
  				SCTP_TCB_UNLOCK(stcb);
  				SCTP_SOCKET_LOCK(so, 1);
  				SCTP_TCB_LOCK(stcb);
  				atomic_add_int(&stcb->asoc.refcnt, -1);
  				if (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET) {
  					SCTP_SOCKET_UNLOCK(so, 1);
  					return (NULL);
  				}
  #endif
  				soisconnected(stcb->sctp_socket);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  				SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  			}
  			if (SCTP_GET_STATE(asoc) == SCTP_STATE_COOKIE_ECHOED)
  				SCTP_STAT_INCR_COUNTER32(sctps_activeestab);
  			else
  				SCTP_STAT_INCR_COUNTER32(sctps_collisionestab);
  			SCTP_STAT_INCR_GAUGE32(sctps_currestab);
  		} else if (SCTP_GET_STATE(asoc) == SCTP_STATE_OPEN) {
  			SCTP_STAT_INCR_COUNTER32(sctps_restartestab);
  		} else {
  			SCTP_STAT_INCR_COUNTER32(sctps_collisionestab);
  		}
  		SCTP_SET_STATE(asoc, SCTP_STATE_OPEN);
  		if (asoc->state & SCTP_STATE_SHUTDOWN_PENDING) {
  			sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
  					 stcb->sctp_ep, stcb, asoc->primary_destination);
  		}
  		sctp_stop_all_cookie_timers(stcb);
  		sctp_toss_old_cookies(stcb, asoc);
  		sctp_send_cookie_ack(stcb);
  		if (spec_flag) {
  			/* only if we have retrans set do we do this. What
  			 * this call does is get only the COOKIE-ACK out
  			 * and then when we return the normal call to
  			 * sctp_chunk_output will get the retrans out
  			 * behind this.
  			 */
  			sctp_chunk_output(inp,stcb, SCTP_OUTPUT_FROM_COOKIE_ACK, SCTP_SO_NOT_LOCKED);
  		}
  		if (how_indx < sizeof(asoc->cookie_how))
  			asoc->cookie_how[how_indx] = 11;
  
  		return (stcb);
  	}
  	if ((ntohl(initack_cp->init.initiate_tag) != asoc->my_vtag &&
  	     ntohl(init_cp->init.initiate_tag) != asoc->peer_vtag) &&
  	    cookie->tie_tag_my_vtag == asoc->my_vtag_nonce &&
  	    cookie->tie_tag_peer_vtag == asoc->peer_vtag_nonce &&
  	    cookie->tie_tag_peer_vtag != 0) {
  		struct sctpasochead *head;
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		struct socket *so;
  #endif
  
  		if (asoc->peer_supports_nat) {
  			/* This is a gross gross hack.
  			 * Just call the cookie_new code since we
  			 * are allowing a duplicate association.
  			 * I hope this works...
  			 */
  			return (sctp_process_cookie_new(m, iphlen, offset, src, dst,
  			                                sh, cookie, cookie_len,
  			                                inp, netp, init_src,notification,
  			                                auth_skipped, auth_offset, auth_len,
  #if defined(__FreeBSD__)
  			                                mflowtype, mflowid,
  #endif
  			                                vrf_id, port));
  		}
  		/*
  		 * case A in Section 5.2.4 Table 2: XXMM (peer restarted)
  		 */
  		/* temp code */
  		if (how_indx < sizeof(asoc->cookie_how))
  			asoc->cookie_how[how_indx] = 12;
  		sctp_timer_stop(SCTP_TIMER_TYPE_INIT, inp, stcb, net,
  		                SCTP_FROM_SCTP_INPUT + SCTP_LOC_16);
  		sctp_timer_stop(SCTP_TIMER_TYPE_HEARTBEAT, inp, stcb, net,
  		                SCTP_FROM_SCTP_INPUT + SCTP_LOC_17);
  
  		/* notify upper layer */
  		*notification = SCTP_NOTIFY_ASSOC_RESTART;
  		atomic_add_int(&stcb->asoc.refcnt, 1);
  		if ((SCTP_GET_STATE(asoc) != SCTP_STATE_OPEN) &&
  		    (SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_RECEIVED) &&
  		    (SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_SENT)) {
  			SCTP_STAT_INCR_GAUGE32(sctps_currestab);
  		}
  		if (SCTP_GET_STATE(asoc) == SCTP_STATE_OPEN) {
  			SCTP_STAT_INCR_GAUGE32(sctps_restartestab);
  		} else if (SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_SENT) {
  			SCTP_STAT_INCR_GAUGE32(sctps_collisionestab);
  		}
  		if (asoc->state & SCTP_STATE_SHUTDOWN_PENDING) {
  			SCTP_SET_STATE(asoc, SCTP_STATE_OPEN);
  			sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
  					 stcb->sctp_ep, stcb, asoc->primary_destination);
  
  		} else if (!(asoc->state & SCTP_STATE_SHUTDOWN_SENT)) {
  			/* move to OPEN state, if not in SHUTDOWN_SENT */
  			SCTP_SET_STATE(asoc, SCTP_STATE_OPEN);
  		}
  		asoc->pre_open_streams =
  			ntohs(initack_cp->init.num_outbound_streams);
  		asoc->init_seq_number = ntohl(initack_cp->init.initial_tsn);
  		asoc->sending_seq = asoc->asconf_seq_out = asoc->str_reset_seq_out = asoc->init_seq_number;
  		asoc->asconf_seq_out_acked = asoc->asconf_seq_out - 1;
  
  		asoc->asconf_seq_in = asoc->last_acked_seq = asoc->init_seq_number - 1;
  
  		asoc->str_reset_seq_in = asoc->init_seq_number;
  
  		asoc->advanced_peer_ack_point = asoc->last_acked_seq;
  		if (asoc->mapping_array) {
  			memset(asoc->mapping_array, 0,
  			       asoc->mapping_array_size);
  		}
  		if (asoc->nr_mapping_array) {
  			memset(asoc->nr_mapping_array, 0,
  			    asoc->mapping_array_size);
  		}
  		SCTP_TCB_UNLOCK(stcb);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		so = SCTP_INP_SO(stcb->sctp_ep);
  		SCTP_SOCKET_LOCK(so, 1);
  #endif
  		SCTP_INP_INFO_WLOCK();
  		SCTP_INP_WLOCK(stcb->sctp_ep);
  		SCTP_TCB_LOCK(stcb);
  		atomic_add_int(&stcb->asoc.refcnt, -1);
  		/* send up all the data */
  		SCTP_TCB_SEND_LOCK(stcb);
  
  		sctp_report_all_outbound(stcb, 0, 1, SCTP_SO_LOCKED);
  		for (i = 0; i < stcb->asoc.streamoutcnt; i++) {
  			stcb->asoc.strmout[i].chunks_on_queues = 0;
  #if defined(SCTP_DETAILED_STR_STATS)
  			for (j = 0; j < SCTP_PR_SCTP_MAX + 1; j++) {
  				asoc->strmout[i].abandoned_sent[j] = 0;
  				asoc->strmout[i].abandoned_unsent[j] = 0;
  			}
  #else
  			asoc->strmout[i].abandoned_sent[0] = 0;
  			asoc->strmout[i].abandoned_unsent[0] = 0;
  #endif
  			stcb->asoc.strmout[i].stream_no = i;
  			stcb->asoc.strmout[i].next_mid_ordered = 0;
  			stcb->asoc.strmout[i].next_mid_unordered = 0;
  			stcb->asoc.strmout[i].last_msg_incomplete = 0;
  		}
  		/* process the INIT-ACK info (my info) */
  		asoc->my_vtag = ntohl(initack_cp->init.initiate_tag);
  		asoc->my_rwnd = ntohl(initack_cp->init.a_rwnd);
  
  		/* pull from vtag hash */
  		LIST_REMOVE(stcb, sctp_asocs);
  		/* re-insert to new vtag position */
  		head = &SCTP_BASE_INFO(sctp_asochash)[SCTP_PCBHASH_ASOC(stcb->asoc.my_vtag,
  								    SCTP_BASE_INFO(hashasocmark))];
  		/*
  		 * put it in the bucket in the vtag hash of assoc's for the
  		 * system
  		 */
  		LIST_INSERT_HEAD(head, stcb, sctp_asocs);
  
  		SCTP_TCB_SEND_UNLOCK(stcb);
  		SCTP_INP_WUNLOCK(stcb->sctp_ep);
  		SCTP_INP_INFO_WUNLOCK();
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  		asoc->total_flight = 0;
  		asoc->total_flight_count = 0;
  		/* process the INIT info (peer's info) */
  		retval = sctp_process_init(init_cp, stcb);
  		if (retval < 0) {
  			if (how_indx < sizeof(asoc->cookie_how))
  				asoc->cookie_how[how_indx] = 13;
  
  			return (NULL);
  		}
  		/*
  		 * since we did not send a HB make sure we don't double
  		 * things
  		 */
  		net->hb_responded = 1;
  
  		if (sctp_load_addresses_from_init(stcb, m,
  						  init_offset + sizeof(struct sctp_init_chunk),
  						  initack_offset, src, dst, init_src, stcb->asoc.port)) {
  			if (how_indx < sizeof(asoc->cookie_how))
  				asoc->cookie_how[how_indx] = 14;
  
  			return (NULL);
  		}
  		/* respond with a COOKIE-ACK */
  		sctp_stop_all_cookie_timers(stcb);
  		sctp_toss_old_cookies(stcb, asoc);
  		sctp_send_cookie_ack(stcb);
  		if (how_indx < sizeof(asoc->cookie_how))
  			asoc->cookie_how[how_indx] = 15;
  
  		return (stcb);
  	}
  	if (how_indx < sizeof(asoc->cookie_how))
  		asoc->cookie_how[how_indx] = 16;
  	/* all other cases... */
  	return (NULL);
  }
  
  
  /*
   * handle a state cookie for a new association m: input packet mbuf chain--
   * assumes a pullup on IP/SCTP/COOKIE-ECHO chunk note: this is a "split" mbuf
   * and the cookie signature does not exist offset: offset into mbuf to the
   * cookie-echo chunk length: length of the cookie chunk to: where the init
   * was from returns a new TCB
   */
  static struct sctp_tcb *
  sctp_process_cookie_new(struct mbuf *m, int iphlen, int offset,
      struct sockaddr *src, struct sockaddr *dst,
      struct sctphdr *sh, struct sctp_state_cookie *cookie, int cookie_len,
      struct sctp_inpcb *inp, struct sctp_nets **netp,
      struct sockaddr *init_src, int *notification,
      int auth_skipped, uint32_t auth_offset, uint32_t auth_len,
  #if defined(__FreeBSD__)
      uint8_t mflowtype, uint32_t mflowid,
  #endif
      uint32_t vrf_id, uint16_t port)
  {
  	struct sctp_tcb *stcb;
  	struct sctp_init_chunk *init_cp, init_buf;
  	struct sctp_init_ack_chunk *initack_cp, initack_buf;
  	union sctp_sockstore store;
  	struct sctp_association *asoc;
  	int init_offset, initack_offset, initack_limit;
  	int retval;
  	int error = 0;
  	uint8_t auth_chunk_buf[SCTP_PARAM_BUFFER_SIZE];
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  	struct socket *so;
  
  	so = SCTP_INP_SO(inp);
  #endif
  
  	/*
  	 * find and validate the INIT chunk in the cookie (peer's info) the
  	 * INIT should start after the cookie-echo header struct (chunk
  	 * header, state cookie header struct)
  	 */
  	init_offset = offset + sizeof(struct sctp_cookie_echo_chunk);
  	init_cp = (struct sctp_init_chunk *)
  	    sctp_m_getptr(m, init_offset, sizeof(struct sctp_init_chunk),
  	    (uint8_t *) & init_buf);
  	if (init_cp == NULL) {
  		/* could not pull a INIT chunk in cookie */
  		SCTPDBG(SCTP_DEBUG_INPUT1,
  			"process_cookie_new: could not pull INIT chunk hdr\n");
  		return (NULL);
  	}
  	if (init_cp->ch.chunk_type != SCTP_INITIATION) {
  		SCTPDBG(SCTP_DEBUG_INPUT1, "HUH? process_cookie_new: could not find INIT chunk!\n");
  		return (NULL);
  	}
  	initack_offset = init_offset + SCTP_SIZE32(ntohs(init_cp->ch.chunk_length));
  	/*
  	 * find and validate the INIT-ACK chunk in the cookie (my info) the
  	 * INIT-ACK follows the INIT chunk
  	 */
  	initack_cp = (struct sctp_init_ack_chunk *)
  	    sctp_m_getptr(m, initack_offset, sizeof(struct sctp_init_ack_chunk),
  	    (uint8_t *) & initack_buf);
  	if (initack_cp == NULL) {
  		/* could not pull INIT-ACK chunk in cookie */
  		SCTPDBG(SCTP_DEBUG_INPUT1, "process_cookie_new: could not pull INIT-ACK chunk hdr\n");
  		return (NULL);
  	}
  	if (initack_cp->ch.chunk_type != SCTP_INITIATION_ACK) {
  		return (NULL);
  	}
  	/*
  	 * NOTE: We can't use the INIT_ACK's chk_length to determine the
  	 * "initack_limit" value.  This is because the chk_length field
  	 * includes the length of the cookie, but the cookie is omitted when
  	 * the INIT and INIT_ACK are tacked onto the cookie...
  	 */
  	initack_limit = offset + cookie_len;
  
  	/*
  	 * now that we know the INIT/INIT-ACK are in place, create a new TCB
  	 * and popluate
  	 */
  
  	/*
  	 * Here we do a trick, we set in NULL for the proc/thread argument. We
  	 * do this since in effect we only use the p argument when
  	 * the socket is unbound and we must do an implicit bind.
  	 * Since we are getting a cookie, we cannot be unbound.
  	 */
  	stcb = sctp_aloc_assoc(inp, init_src, &error,
  	                       ntohl(initack_cp->init.initiate_tag), vrf_id,
  	                       ntohs(initack_cp->init.num_outbound_streams),
  	                       port,
  #if defined(__FreeBSD__) && __FreeBSD_version >= 500000
  	                       (struct thread *)NULL
  #elif defined(__Windows__)
  	                       (PKTHREAD)NULL
  #else
  	                       (struct proc *)NULL
  #endif
  	                       );
  	if (stcb == NULL) {
  		struct mbuf *op_err;
  
  		/* memory problem? */
  		SCTPDBG(SCTP_DEBUG_INPUT1,
  			"process_cookie_new: no room for another TCB!\n");
  		op_err = sctp_generate_cause(SCTP_CAUSE_OUT_OF_RESC, "");
  		sctp_abort_association(inp, (struct sctp_tcb *)NULL, m, iphlen,
  		                       src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  		                       mflowtype, mflowid,
  #endif
  		                       vrf_id, port);
  		return (NULL);
  	}
  	/* get the correct sctp_nets */
  	if (netp)
  		*netp = sctp_findnet(stcb, init_src);
  
  	asoc = &stcb->asoc;
  	/* get scope variables out of cookie */
  	asoc->scope.ipv4_local_scope = cookie->ipv4_scope;
  	asoc->scope.site_scope = cookie->site_scope;
  	asoc->scope.local_scope = cookie->local_scope;
  	asoc->scope.loopback_scope = cookie->loopback_scope;
  
  #if defined(__Userspace__)
  	if ((asoc->scope.ipv4_addr_legal != cookie->ipv4_addr_legal) ||
  	    (asoc->scope.ipv6_addr_legal != cookie->ipv6_addr_legal) ||
  	    (asoc->scope.conn_addr_legal != cookie->conn_addr_legal)) {
  #else
  	if ((asoc->scope.ipv4_addr_legal != cookie->ipv4_addr_legal) ||
  	    (asoc->scope.ipv6_addr_legal != cookie->ipv6_addr_legal)) {
  #endif
  		struct mbuf *op_err;
  
  		/*
  		 * Houston we have a problem. The EP changed while the
  		 * cookie was in flight. Only recourse is to abort the
  		 * association.
  		 */
  		atomic_add_int(&stcb->asoc.refcnt, 1);
  		op_err = sctp_generate_cause(SCTP_CAUSE_OUT_OF_RESC, "");
  		sctp_abort_association(inp, (struct sctp_tcb *)NULL, m, iphlen,
  				       src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  		                       mflowtype, mflowid,
  #endif
  		                       vrf_id, port);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		SCTP_TCB_UNLOCK(stcb);
  		SCTP_SOCKET_LOCK(so, 1);
  		SCTP_TCB_LOCK(stcb);
  #endif
  		(void)sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC,
  				      SCTP_FROM_SCTP_INPUT + SCTP_LOC_18);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  		atomic_subtract_int(&stcb->asoc.refcnt, 1);
  		return (NULL);
  	}
  	/* process the INIT-ACK info (my info) */
  	asoc->my_vtag = ntohl(initack_cp->init.initiate_tag);
  	asoc->my_rwnd = ntohl(initack_cp->init.a_rwnd);
  	asoc->pre_open_streams = ntohs(initack_cp->init.num_outbound_streams);
  	asoc->init_seq_number = ntohl(initack_cp->init.initial_tsn);
  	asoc->sending_seq = asoc->asconf_seq_out = asoc->str_reset_seq_out = asoc->init_seq_number;
  	asoc->asconf_seq_out_acked = asoc->asconf_seq_out - 1;
  	asoc->asconf_seq_in = asoc->last_acked_seq = asoc->init_seq_number - 1;
  	asoc->str_reset_seq_in = asoc->init_seq_number;
  
  	asoc->advanced_peer_ack_point = asoc->last_acked_seq;
  
  	/* process the INIT info (peer's info) */
  	if (netp)
  		retval = sctp_process_init(init_cp, stcb);
  	else
  		retval = 0;
  	if (retval < 0) {
  		atomic_add_int(&stcb->asoc.refcnt, 1);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		SCTP_TCB_UNLOCK(stcb);
  		SCTP_SOCKET_LOCK(so, 1);
  		SCTP_TCB_LOCK(stcb);
  #endif
  		(void)sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC,
  		                      SCTP_FROM_SCTP_INPUT + SCTP_LOC_19);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  		atomic_subtract_int(&stcb->asoc.refcnt, 1);
  		return (NULL);
  	}
  	/* load all addresses */
  	if (sctp_load_addresses_from_init(stcb, m,
  	    init_offset + sizeof(struct sctp_init_chunk), initack_offset,
  	    src, dst, init_src, port)) {
  		atomic_add_int(&stcb->asoc.refcnt, 1);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		SCTP_TCB_UNLOCK(stcb);
  		SCTP_SOCKET_LOCK(so, 1);
  		SCTP_TCB_LOCK(stcb);
  #endif
  		(void)sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC,
  		                      SCTP_FROM_SCTP_INPUT + SCTP_LOC_20);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  		atomic_subtract_int(&stcb->asoc.refcnt, 1);
  		return (NULL);
  	}
  	/*
  	 * verify any preceding AUTH chunk that was skipped
  	 */
  	/* pull the local authentication parameters from the cookie/init-ack */
  	sctp_auth_get_cookie_params(stcb, m,
  	    initack_offset + sizeof(struct sctp_init_ack_chunk),
  	    initack_limit - (initack_offset + sizeof(struct sctp_init_ack_chunk)));
  	if (auth_skipped) {
  		struct sctp_auth_chunk *auth;
  
  		auth = (struct sctp_auth_chunk *)
  		    sctp_m_getptr(m, auth_offset, auth_len, auth_chunk_buf);
  		if ((auth == NULL) || sctp_handle_auth(stcb, auth, m, auth_offset)) {
  			/* auth HMAC failed, dump the assoc and packet */
  			SCTPDBG(SCTP_DEBUG_AUTH1,
  				"COOKIE-ECHO: AUTH failed\n");
  			atomic_add_int(&stcb->asoc.refcnt, 1);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  			SCTP_TCB_UNLOCK(stcb);
  			SCTP_SOCKET_LOCK(so, 1);
  			SCTP_TCB_LOCK(stcb);
  #endif
  			(void)sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC,
  			                      SCTP_FROM_SCTP_INPUT + SCTP_LOC_21);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  			SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  			atomic_subtract_int(&stcb->asoc.refcnt, 1);
  			return (NULL);
  		} else {
  			/* remaining chunks checked... good to go */
  			stcb->asoc.authenticated = 1;
  		}
  	}
  	/* update current state */
  	SCTPDBG(SCTP_DEBUG_INPUT2, "moving to OPEN state\n");
  	SCTP_SET_STATE(asoc, SCTP_STATE_OPEN);
  	if (asoc->state & SCTP_STATE_SHUTDOWN_PENDING) {
  		sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
  				 stcb->sctp_ep, stcb, asoc->primary_destination);
  	}
  	sctp_stop_all_cookie_timers(stcb);
  	SCTP_STAT_INCR_COUNTER32(sctps_passiveestab);
  	SCTP_STAT_INCR_GAUGE32(sctps_currestab);
  
  	/*
  	 * if we're doing ASCONFs, check to see if we have any new local
  	 * addresses that need to get added to the peer (eg. addresses
  	 * changed while cookie echo in flight).  This needs to be done
  	 * after we go to the OPEN state to do the correct asconf
  	 * processing. else, make sure we have the correct addresses in our
  	 * lists
  	 */
  
  	/* warning, we re-use sin, sin6, sa_store here! */
  	/* pull in local_address (our "from" address) */
  	switch (cookie->laddr_type) {
  #ifdef INET
  	case SCTP_IPV4_ADDRESS:
  		/* source addr is IPv4 */
  		memset(&store.sin, 0, sizeof(struct sockaddr_in));
  		store.sin.sin_family = AF_INET;
  #ifdef HAVE_SIN_LEN
  		store.sin.sin_len = sizeof(struct sockaddr_in);
  #endif
  		store.sin.sin_addr.s_addr = cookie->laddress[0];
  		break;
  #endif
  #ifdef INET6
  	case SCTP_IPV6_ADDRESS:
  		/* source addr is IPv6 */
  		memset(&store.sin6, 0, sizeof(struct sockaddr_in6));
  		store.sin6.sin6_family = AF_INET6;
  #ifdef HAVE_SIN6_LEN
  		store.sin6.sin6_len = sizeof(struct sockaddr_in6);
  #endif
  		store.sin6.sin6_scope_id = cookie->scope_id;
  		memcpy(&store.sin6.sin6_addr, cookie->laddress, sizeof(struct in6_addr));
  		break;
  #endif
  #if defined(__Userspace__)
  	case SCTP_CONN_ADDRESS:
  		/* source addr is conn */
  		memset(&store.sconn, 0, sizeof(struct sockaddr_conn));
  		store.sconn.sconn_family = AF_CONN;
  #ifdef HAVE_SCONN_LEN
  		store.sconn.sconn_len = sizeof(struct sockaddr_conn);
  #endif
  		memcpy(&store.sconn.sconn_addr, cookie->laddress, sizeof(void *));
  		break;
  #endif
  	default:
  		atomic_add_int(&stcb->asoc.refcnt, 1);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		SCTP_TCB_UNLOCK(stcb);
  		SCTP_SOCKET_LOCK(so, 1);
  		SCTP_TCB_LOCK(stcb);
  #endif
  		(void)sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC,
  		                      SCTP_FROM_SCTP_INPUT + SCTP_LOC_22);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  		atomic_subtract_int(&stcb->asoc.refcnt, 1);
  		return (NULL);
  	}
  
  	/* set up to notify upper layer */
  	*notification = SCTP_NOTIFY_ASSOC_UP;
  	if (((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) ||
  	    (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_IN_TCPPOOL)) &&
  	    (inp->sctp_socket->so_qlimit == 0)) {
  		/*
  		 * This is an endpoint that called connect() how it got a
  		 * cookie that is NEW is a bit of a mystery. It must be that
  		 * the INIT was sent, but before it got there.. a complete
  		 * INIT/INIT-ACK/COOKIE arrived. But of course then it
  		 * should have went to the other code.. not here.. oh well..
  		 * a bit of protection is worth having..
  		 */
  		stcb->sctp_ep->sctp_flags |= SCTP_PCB_FLAGS_CONNECTED;
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		atomic_add_int(&stcb->asoc.refcnt, 1);
  		SCTP_TCB_UNLOCK(stcb);
  		SCTP_SOCKET_LOCK(so, 1);
  		SCTP_TCB_LOCK(stcb);
  		atomic_subtract_int(&stcb->asoc.refcnt, 1);
  		if (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET) {
  			SCTP_SOCKET_UNLOCK(so, 1);
  			return (NULL);
  		}
  #endif
  		soisconnected(stcb->sctp_socket);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  	} else if ((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) &&
  	    (inp->sctp_socket->so_qlimit)) {
  		/*
  		 * We don't want to do anything with this one. Since it is
  		 * the listening guy. The timer will get started for
  		 * accepted connections in the caller.
  		 */
  		;
  	}
  	/* since we did not send a HB make sure we don't double things */
  	if ((netp) && (*netp))
  		(*netp)->hb_responded = 1;
  
  	if (stcb->asoc.sctp_autoclose_ticks &&
  	    sctp_is_feature_on(inp, SCTP_PCB_FLAGS_AUTOCLOSE)) {
  		sctp_timer_start(SCTP_TIMER_TYPE_AUTOCLOSE, inp, stcb, NULL);
  	}
  	(void)SCTP_GETTIME_TIMEVAL(&stcb->asoc.time_entered);
  	if ((netp != NULL) && (*netp != NULL)) {
  		/* calculate the RTT and set the encaps port */
  		(*netp)->RTO = sctp_calculate_rto(stcb, asoc, *netp,
  						  &cookie->time_entered, sctp_align_unsafe_makecopy,
  						  SCTP_RTT_FROM_NON_DATA);
  	}
  	/* respond with a COOKIE-ACK */
  	sctp_send_cookie_ack(stcb);
  
  	/*
  	 * check the address lists for any ASCONFs that need to be sent
  	 * AFTER the cookie-ack is sent
  	 */
  	sctp_check_address_list(stcb, m,
  	    initack_offset + sizeof(struct sctp_init_ack_chunk),
  	    initack_limit - (initack_offset + sizeof(struct sctp_init_ack_chunk)),
  	    &store.sa, cookie->local_scope, cookie->site_scope,
  	    cookie->ipv4_scope, cookie->loopback_scope);
  
  
  	return (stcb);
  }
  
  /*
   * CODE LIKE THIS NEEDS TO RUN IF the peer supports the NAT extension, i.e
   * we NEED to make sure we are not already using the vtag. If so we
   * need to send back an ABORT-TRY-AGAIN-WITH-NEW-TAG No middle box bit!
  	head = &SCTP_BASE_INFO(sctp_asochash)[SCTP_PCBHASH_ASOC(tag,
  							    SCTP_BASE_INFO(hashasocmark))];
  	LIST_FOREACH(stcb, head, sctp_asocs) {
  	        if ((stcb->asoc.my_vtag == tag) && (stcb->rport == rport) && (inp == stcb->sctp_ep))  {
  		       -- SEND ABORT - TRY AGAIN --
  		}
  	}
  */
  
  /*
   * handles a COOKIE-ECHO message stcb: modified to either a new or left as
   * existing (non-NULL) TCB
   */
  static struct mbuf *
  sctp_handle_cookie_echo(struct mbuf *m, int iphlen, int offset,
      struct sockaddr *src, struct sockaddr *dst,
      struct sctphdr *sh, struct sctp_cookie_echo_chunk *cp,
      struct sctp_inpcb **inp_p, struct sctp_tcb **stcb, struct sctp_nets **netp,
      int auth_skipped, uint32_t auth_offset, uint32_t auth_len,
      struct sctp_tcb **locked_tcb,
  #if defined(__FreeBSD__)
      uint8_t mflowtype, uint32_t mflowid,
  #endif
      uint32_t vrf_id, uint16_t port)
  {
  	struct sctp_state_cookie *cookie;
  	struct sctp_tcb *l_stcb = *stcb;
  	struct sctp_inpcb *l_inp;
  	struct sockaddr *to;
  	struct sctp_pcb *ep;
  	struct mbuf *m_sig;
  	uint8_t calc_sig[SCTP_SIGNATURE_SIZE], tmp_sig[SCTP_SIGNATURE_SIZE];
  	uint8_t *sig;
  	uint8_t cookie_ok = 0;
  	unsigned int sig_offset, cookie_offset;
  	unsigned int cookie_len;
  	struct timeval now;
  	struct timeval time_expires;
  	int notification = 0;
  	struct sctp_nets *netl;
  	int had_a_existing_tcb = 0;
  	int send_int_conf = 0;
  #ifdef INET
  	struct sockaddr_in sin;
  #endif
  #ifdef INET6
  	struct sockaddr_in6 sin6;
  #endif
  #if defined(__Userspace__)
  	struct sockaddr_conn sconn;
  #endif
  
  	SCTPDBG(SCTP_DEBUG_INPUT2,
  		"sctp_handle_cookie: handling COOKIE-ECHO\n");
  
  	if (inp_p == NULL) {
  		return (NULL);
  	}
  	cookie = &cp->cookie;
  	cookie_offset = offset + sizeof(struct sctp_chunkhdr);
  	cookie_len = ntohs(cp->ch.chunk_length);
  
  	if ((cookie->peerport != sh->src_port) ||
  	    (cookie->myport != sh->dest_port) ||
  	    (cookie->my_vtag != sh->v_tag)) {
  		/*
  		 * invalid ports or bad tag.  Note that we always leave the
  		 * v_tag in the header in network order and when we stored
  		 * it in the my_vtag slot we also left it in network order.
  		 * This maintains the match even though it may be in the
  		 * opposite byte order of the machine :->
  		 */
  		return (NULL);
  	}
  	if (cookie_len < sizeof(struct sctp_cookie_echo_chunk) +
  	    sizeof(struct sctp_init_chunk) +
  	    sizeof(struct sctp_init_ack_chunk) + SCTP_SIGNATURE_SIZE) {
  		/* cookie too small */
  		return (NULL);
  	}
  	/*
  	 * split off the signature into its own mbuf (since it should not be
  	 * calculated in the sctp_hmac_m() call).
  	 */
  	sig_offset = offset + cookie_len - SCTP_SIGNATURE_SIZE;
  	m_sig = m_split(m, sig_offset, M_NOWAIT);
  	if (m_sig == NULL) {
  		/* out of memory or ?? */
  		return (NULL);
  	}
  #ifdef SCTP_MBUF_LOGGING
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MBUF_LOGGING_ENABLE) {
  		sctp_log_mbc(m_sig, SCTP_MBUF_SPLIT);
  	}
  #endif
  
  	/*
  	 * compute the signature/digest for the cookie
  	 */
  	ep = &(*inp_p)->sctp_ep;
  	l_inp = *inp_p;
  	if (l_stcb) {
  		SCTP_TCB_UNLOCK(l_stcb);
  	}
  	SCTP_INP_RLOCK(l_inp);
  	if (l_stcb) {
  		SCTP_TCB_LOCK(l_stcb);
  	}
  	/* which cookie is it? */
  	if ((cookie->time_entered.tv_sec < (long)ep->time_of_secret_change) &&
  	    (ep->current_secret_number != ep->last_secret_number)) {
  		/* it's the old cookie */
  		(void)sctp_hmac_m(SCTP_HMAC,
  		    (uint8_t *)ep->secret_key[(int)ep->last_secret_number],
  		    SCTP_SECRET_SIZE, m, cookie_offset, calc_sig, 0);
  	} else {
  		/* it's the current cookie */
  		(void)sctp_hmac_m(SCTP_HMAC,
  		    (uint8_t *)ep->secret_key[(int)ep->current_secret_number],
  		    SCTP_SECRET_SIZE, m, cookie_offset, calc_sig, 0);
  	}
  	/* get the signature */
  	SCTP_INP_RUNLOCK(l_inp);
  	sig = (uint8_t *) sctp_m_getptr(m_sig, 0, SCTP_SIGNATURE_SIZE, (uint8_t *) & tmp_sig);
  	if (sig == NULL) {
  		/* couldn't find signature */
  		sctp_m_freem(m_sig);
  		return (NULL);
  	}
  	/* compare the received digest with the computed digest */
  	if (memcmp(calc_sig, sig, SCTP_SIGNATURE_SIZE) != 0) {
  		/* try the old cookie? */
  		if ((cookie->time_entered.tv_sec == (long)ep->time_of_secret_change) &&
  		    (ep->current_secret_number != ep->last_secret_number)) {
  			/* compute digest with old */
  			(void)sctp_hmac_m(SCTP_HMAC,
  			    (uint8_t *)ep->secret_key[(int)ep->last_secret_number],
  			    SCTP_SECRET_SIZE, m, cookie_offset, calc_sig, 0);
  			/* compare */
  			if (memcmp(calc_sig, sig, SCTP_SIGNATURE_SIZE) == 0)
  				cookie_ok = 1;
  		}
  	} else {
  		cookie_ok = 1;
  	}
  
  	/*
  	 * Now before we continue we must reconstruct our mbuf so that
  	 * normal processing of any other chunks will work.
  	 */
  	{
  		struct mbuf *m_at;
  
  		m_at = m;
  		while (SCTP_BUF_NEXT(m_at) != NULL) {
  			m_at = SCTP_BUF_NEXT(m_at);
  		}
  		SCTP_BUF_NEXT(m_at) = m_sig;
  	}
  
  	if (cookie_ok == 0) {
  		SCTPDBG(SCTP_DEBUG_INPUT2, "handle_cookie_echo: cookie signature validation failed!\n");
  		SCTPDBG(SCTP_DEBUG_INPUT2,
  			"offset = %u, cookie_offset = %u, sig_offset = %u\n",
  			(uint32_t) offset, cookie_offset, sig_offset);
  		return (NULL);
  	}
  
  	/*
  	 * check the cookie timestamps to be sure it's not stale
  	 */
  	(void)SCTP_GETTIME_TIMEVAL(&now);
  	/* Expire time is in Ticks, so we convert to seconds */
  	time_expires.tv_sec = cookie->time_entered.tv_sec + TICKS_TO_SEC(cookie->cookie_life);
  	time_expires.tv_usec = cookie->time_entered.tv_usec;
          /* TODO sctp_constants.h needs alternative time macros when
           *  _KERNEL is undefined.
           */
  #ifndef __FreeBSD__
  	if (timercmp(&now, &time_expires, >))
  #else
  	if (timevalcmp(&now, &time_expires, >))
  #endif
  	{
  		/* cookie is stale! */
  		struct mbuf *op_err;
  		struct sctp_error_stale_cookie *cause;
  		uint32_t tim;
  		op_err = sctp_get_mbuf_for_msg(sizeof(struct sctp_error_stale_cookie),
  					       0, M_NOWAIT, 1, MT_DATA);
  		if (op_err == NULL) {
  			/* FOOBAR */
  			return (NULL);
  		}
  		/* Set the len */
  		SCTP_BUF_LEN(op_err) = sizeof(struct sctp_error_stale_cookie);
  		cause = mtod(op_err, struct sctp_error_stale_cookie *);
  		cause->cause.code = htons(SCTP_CAUSE_STALE_COOKIE);
  		cause->cause.length = htons((sizeof(struct sctp_paramhdr) +
  		    (sizeof(uint32_t))));
  		/* seconds to usec */
  		tim = (now.tv_sec - time_expires.tv_sec) * 1000000;
  		/* add in usec */
  		if (tim == 0)
  			tim = now.tv_usec - cookie->time_entered.tv_usec;
  		cause->stale_time = htonl(tim);
  		sctp_send_operr_to(src, dst, sh, cookie->peers_vtag, op_err,
  #if defined(__FreeBSD__)
  		                   mflowtype, mflowid, l_inp->fibnum,
  #endif
  		                   vrf_id, port);
  		return (NULL);
  	}
  	/*
  	 * Now we must see with the lookup address if we have an existing
  	 * asoc. This will only happen if we were in the COOKIE-WAIT state
  	 * and a INIT collided with us and somewhere the peer sent the
  	 * cookie on another address besides the single address our assoc
  	 * had for him. In this case we will have one of the tie-tags set at
  	 * least AND the address field in the cookie can be used to look it
  	 * up.
  	 */
  	to = NULL;
  	switch (cookie->addr_type) {
  #ifdef INET6
  	case SCTP_IPV6_ADDRESS:
  		memset(&sin6, 0, sizeof(sin6));
  		sin6.sin6_family = AF_INET6;
  #ifdef HAVE_SIN6_LEN
  		sin6.sin6_len = sizeof(sin6);
  #endif
  		sin6.sin6_port = sh->src_port;
  		sin6.sin6_scope_id = cookie->scope_id;
  		memcpy(&sin6.sin6_addr.s6_addr, cookie->address,
  		    sizeof(sin6.sin6_addr.s6_addr));
  		to = (struct sockaddr *)&sin6;
  		break;
  #endif
  #ifdef INET
  	case SCTP_IPV4_ADDRESS:
  		memset(&sin, 0, sizeof(sin));
  		sin.sin_family = AF_INET;
  #ifdef HAVE_SIN_LEN
  		sin.sin_len = sizeof(sin);
  #endif
  		sin.sin_port = sh->src_port;
  		sin.sin_addr.s_addr = cookie->address[0];
  		to = (struct sockaddr *)&sin;
  		break;
  #endif
  #if defined(__Userspace__)
  	case SCTP_CONN_ADDRESS:
  		memset(&sconn, 0, sizeof(struct sockaddr_conn));
  		sconn.sconn_family = AF_CONN;
  #ifdef HAVE_SCONN_LEN
  		sconn.sconn_len = sizeof(struct sockaddr_conn);
  #endif
  		sconn.sconn_port = sh->src_port;
  		memcpy(&sconn.sconn_addr, cookie->address, sizeof(void *));
  		to = (struct sockaddr *)&sconn;
  		break;
  #endif
  	default:
  		/* This should not happen */
  		return (NULL);
  	}
  	if (*stcb == NULL) {
  		/* Yep, lets check */
  		*stcb = sctp_findassociation_ep_addr(inp_p, to, netp, dst, NULL);
  		if (*stcb == NULL) {
  			/*
  			 * We should have only got back the same inp. If we
  			 * got back a different ep we have a problem. The
  			 * original findep got back l_inp and now
  			 */
  			if (l_inp != *inp_p) {
  				SCTP_PRINTF("Bad problem find_ep got a diff inp then special_locate?\n");
  			}
  		} else {
  			if (*locked_tcb == NULL) {
  				/* In this case we found the assoc only
  				 * after we locked the create lock. This means
  				 * we are in a colliding case and we must make
  				 * sure that we unlock the tcb if its one of the
  				 * cases where we throw away the incoming packets.
  				 */
  				*locked_tcb = *stcb;
  
  				/* We must also increment the inp ref count
  				 * since the ref_count flags was set when we
  				 * did not find the TCB, now we found it which
  				 * reduces the refcount.. we must raise it back
  				 * out to balance it all :-)
  				 */
  				SCTP_INP_INCR_REF((*stcb)->sctp_ep);
  				if ((*stcb)->sctp_ep != l_inp) {
  					SCTP_PRINTF("Huh? ep:%p diff then l_inp:%p?\n",
  						    (void *)(*stcb)->sctp_ep, (void *)l_inp);
  				}
  			}
  		}
  	}
  
  	cookie_len -= SCTP_SIGNATURE_SIZE;
  	if (*stcb == NULL) {
  		/* this is the "normal" case... get a new TCB */
  		*stcb = sctp_process_cookie_new(m, iphlen, offset, src, dst, sh,
  		                                cookie, cookie_len, *inp_p,
  		                                netp, to, &notification,
  		                                auth_skipped, auth_offset, auth_len,
  #if defined(__FreeBSD__)
  		                                mflowtype, mflowid,
  #endif
  		                                vrf_id, port);
  	} else {
  		/* this is abnormal... cookie-echo on existing TCB */
  		had_a_existing_tcb = 1;
  		*stcb = sctp_process_cookie_existing(m, iphlen, offset,
  		                                     src, dst, sh,
  						     cookie, cookie_len, *inp_p, *stcb, netp, to,
  						     &notification, auth_skipped, auth_offset, auth_len,
  #if defined(__FreeBSD__)
  		                                     mflowtype, mflowid,
  #endif
  		                                     vrf_id, port);
  	}
  
  	if (*stcb == NULL) {
  		/* still no TCB... must be bad cookie-echo */
  		return (NULL);
  	}
  #if defined(__FreeBSD__)
  	if (*netp != NULL) {
  		(*netp)->flowtype = mflowtype;
  		(*netp)->flowid = mflowid;
  	}
  #endif
  	/*
  	 * Ok, we built an association so confirm the address we sent the
  	 * INIT-ACK to.
  	 */
  	netl = sctp_findnet(*stcb, to);
  	/*
  	 * This code should in theory NOT run but
  	 */
  	if (netl == NULL) {
  		/* TSNH! Huh, why do I need to add this address here? */
  		if (sctp_add_remote_addr(*stcb, to, NULL, port,
  		                         SCTP_DONOT_SETSCOPE, SCTP_IN_COOKIE_PROC)) {
  			return (NULL);
  		}
  		netl = sctp_findnet(*stcb, to);
  	}
  	if (netl) {
  		if (netl->dest_state & SCTP_ADDR_UNCONFIRMED) {
  			netl->dest_state &= ~SCTP_ADDR_UNCONFIRMED;
  			(void)sctp_set_primary_addr((*stcb), (struct sockaddr *)NULL,
  			    netl);
  			send_int_conf = 1;
  		}
  	}
  	sctp_start_net_timers(*stcb);
  	if ((*inp_p)->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) {
  		if (!had_a_existing_tcb ||
  		    (((*inp_p)->sctp_flags & SCTP_PCB_FLAGS_CONNECTED) == 0)) {
  			/*
  			 * If we have a NEW cookie or the connect never
  			 * reached the connected state during collision we
  			 * must do the TCP accept thing.
  			 */
  			struct socket *so, *oso;
  			struct sctp_inpcb *inp;
  
  			if (notification == SCTP_NOTIFY_ASSOC_RESTART) {
  				/*
  				 * For a restart we will keep the same
  				 * socket, no need to do anything. I THINK!!
  				 */
  				sctp_ulp_notify(notification, *stcb, 0, NULL, SCTP_SO_NOT_LOCKED);
  				if (send_int_conf) {
  					sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_CONFIRMED,
  					                (*stcb), 0, (void *)netl, SCTP_SO_NOT_LOCKED);
  				}
  				return (m);
  			}
  			oso = (*inp_p)->sctp_socket;
  #if (defined(__FreeBSD__) && __FreeBSD_version < 700000)
  			/*
  			 * We do this to keep the sockets side happy during
  			 * the sonewcon ONLY.
  			 */
  			NET_LOCK_GIANT();
  #endif
  			atomic_add_int(&(*stcb)->asoc.refcnt, 1);
  			SCTP_TCB_UNLOCK((*stcb));
  #if defined(__FreeBSD__) && __FreeBSD_version >= 801000
  			CURVNET_SET(oso->so_vnet);
  #endif
  #if defined(__APPLE__)
  			SCTP_SOCKET_LOCK(oso, 1);
  #endif
  			so = sonewconn(oso, 0
  #if defined(__APPLE__)
  			    ,NULL
  #endif
  #ifdef __Panda__
  			     ,NULL , (*inp_p)->def_vrf_id
  #endif
  			    );
  #if (defined(__FreeBSD__) && __FreeBSD_version < 700000)
  			NET_UNLOCK_GIANT();
  #endif
  #if defined(__APPLE__)
  			SCTP_SOCKET_UNLOCK(oso, 1);
  #endif
  #if defined(__FreeBSD__) && __FreeBSD_version >= 801000
  			CURVNET_RESTORE();
  #endif
  			SCTP_TCB_LOCK((*stcb));
  			atomic_subtract_int(&(*stcb)->asoc.refcnt, 1);
  
  			if (so == NULL) {
  				struct mbuf *op_err;
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  				struct socket *pcb_so;
  #endif
  				/* Too many sockets */
  				SCTPDBG(SCTP_DEBUG_INPUT1, "process_cookie_new: no room for another socket!\n");
  				op_err = sctp_generate_cause(SCTP_CAUSE_OUT_OF_RESC, "");
  				sctp_abort_association(*inp_p, NULL, m, iphlen,
  						       src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  				                       mflowtype, mflowid,
  #endif
  				                       vrf_id, port);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  				pcb_so = SCTP_INP_SO(*inp_p);
  				atomic_add_int(&(*stcb)->asoc.refcnt, 1);
  				SCTP_TCB_UNLOCK((*stcb));
  				SCTP_SOCKET_LOCK(pcb_so, 1);
  				SCTP_TCB_LOCK((*stcb));
  				atomic_subtract_int(&(*stcb)->asoc.refcnt, 1);
  #endif
  				(void)sctp_free_assoc(*inp_p, *stcb, SCTP_NORMAL_PROC,
  				                      SCTP_FROM_SCTP_INPUT + SCTP_LOC_23);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  				SCTP_SOCKET_UNLOCK(pcb_so, 1);
  #endif
  				return (NULL);
  			}
  			inp = (struct sctp_inpcb *)so->so_pcb;
  			SCTP_INP_INCR_REF(inp);
  			/*
  			 * We add the unbound flag here so that
  			 * if we get an soabort() before we get the
  			 * move_pcb done, we will properly cleanup.
  			 */
  			inp->sctp_flags = (SCTP_PCB_FLAGS_TCPTYPE |
  			    SCTP_PCB_FLAGS_CONNECTED |
  			    SCTP_PCB_FLAGS_IN_TCPPOOL |
  			    SCTP_PCB_FLAGS_UNBOUND |
  			    (SCTP_PCB_COPY_FLAGS & (*inp_p)->sctp_flags) |
  			    SCTP_PCB_FLAGS_DONT_WAKE);
  			inp->sctp_features = (*inp_p)->sctp_features;
  			inp->sctp_mobility_features = (*inp_p)->sctp_mobility_features;
  			inp->sctp_socket = so;
  			inp->sctp_frag_point = (*inp_p)->sctp_frag_point;
  			inp->max_cwnd = (*inp_p)->max_cwnd;
  			inp->sctp_cmt_on_off = (*inp_p)->sctp_cmt_on_off;
  			inp->ecn_supported = (*inp_p)->ecn_supported;
  			inp->prsctp_supported = (*inp_p)->prsctp_supported;
  			inp->auth_supported = (*inp_p)->auth_supported;
  			inp->asconf_supported = (*inp_p)->asconf_supported;
  			inp->reconfig_supported = (*inp_p)->reconfig_supported;
  			inp->nrsack_supported = (*inp_p)->nrsack_supported;
  			inp->pktdrop_supported = (*inp_p)->pktdrop_supported;
  			inp->partial_delivery_point = (*inp_p)->partial_delivery_point;
  			inp->sctp_context = (*inp_p)->sctp_context;
  			inp->local_strreset_support = (*inp_p)->local_strreset_support;
  			inp->fibnum = (*inp_p)->fibnum;
  			inp->inp_starting_point_for_iterator = NULL;
  #if defined(__Userspace__)
  			inp->ulp_info = (*inp_p)->ulp_info;
  			inp->recv_callback = (*inp_p)->recv_callback;
  			inp->send_callback = (*inp_p)->send_callback;
  			inp->send_sb_threshold = (*inp_p)->send_sb_threshold;
  #endif
  			/*
  			 * copy in the authentication parameters from the
  			 * original endpoint
  			 */
  			if (inp->sctp_ep.local_hmacs)
  				sctp_free_hmaclist(inp->sctp_ep.local_hmacs);
  			inp->sctp_ep.local_hmacs =
  			    sctp_copy_hmaclist((*inp_p)->sctp_ep.local_hmacs);
  			if (inp->sctp_ep.local_auth_chunks)
  				sctp_free_chunklist(inp->sctp_ep.local_auth_chunks);
  			inp->sctp_ep.local_auth_chunks =
  			    sctp_copy_chunklist((*inp_p)->sctp_ep.local_auth_chunks);
  
  			/*
  			 * Now we must move it from one hash table to
  			 * another and get the tcb in the right place.
  			 */
  
  			/* This is where the one-2-one socket is put into
  			 * the accept state waiting for the accept!
  			 */
  			if (*stcb) {
  				(*stcb)->asoc.state |= SCTP_STATE_IN_ACCEPT_QUEUE;
  			}
  			sctp_move_pcb_and_assoc(*inp_p, inp, *stcb);
  
  			atomic_add_int(&(*stcb)->asoc.refcnt, 1);
  			SCTP_TCB_UNLOCK((*stcb));
  
  #if defined(__FreeBSD__)
  			sctp_pull_off_control_to_new_inp((*inp_p), inp, *stcb,
  			    0);
  #else
  			sctp_pull_off_control_to_new_inp((*inp_p), inp, *stcb, M_NOWAIT);
  #endif
  			SCTP_TCB_LOCK((*stcb));
  			atomic_subtract_int(&(*stcb)->asoc.refcnt, 1);
  
  
  			/* now we must check to see if we were aborted while
  			 * the move was going on and the lock/unlock happened.
  			 */
  			if (inp->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) {
  				/* yep it was, we leave the
  				 * assoc attached to the socket since
  				 * the sctp_inpcb_free() call will send
  				 * an abort for us.
  				 */
  				SCTP_INP_DECR_REF(inp);
  				return (NULL);
  			}
  			SCTP_INP_DECR_REF(inp);
  			/* Switch over to the new guy */
  			*inp_p = inp;
  			sctp_ulp_notify(notification, *stcb, 0, NULL, SCTP_SO_NOT_LOCKED);
  			if (send_int_conf) {
  				sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_CONFIRMED,
  				                (*stcb), 0, (void *)netl, SCTP_SO_NOT_LOCKED);
  			}
  
  			/* Pull it from the incomplete queue and wake the guy */
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  			atomic_add_int(&(*stcb)->asoc.refcnt, 1);
  			SCTP_TCB_UNLOCK((*stcb));
  			SCTP_SOCKET_LOCK(so, 1);
  #endif
  			soisconnected(so);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  			SCTP_TCB_LOCK((*stcb));
  			atomic_subtract_int(&(*stcb)->asoc.refcnt, 1);
  			SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  			return (m);
  		}
  	}
  	if (notification) {
  		sctp_ulp_notify(notification, *stcb, 0, NULL, SCTP_SO_NOT_LOCKED);
  	}
  	if (send_int_conf) {
  		sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_CONFIRMED,
  		                (*stcb), 0, (void *)netl, SCTP_SO_NOT_LOCKED);
  	}
  	return (m);
  }
  
  static void
  sctp_handle_cookie_ack(struct sctp_cookie_ack_chunk *cp SCTP_UNUSED,
      struct sctp_tcb *stcb, struct sctp_nets *net)
  {
  	/* cp must not be used, others call this without a c-ack :-) */
  	struct sctp_association *asoc;
  
  	SCTPDBG(SCTP_DEBUG_INPUT2,
  		"sctp_handle_cookie_ack: handling COOKIE-ACK\n");
  	if ((stcb == NULL) || (net == NULL)) {
  		return;
  	}
  
  	asoc = &stcb->asoc;
  
  	sctp_stop_all_cookie_timers(stcb);
  	/* process according to association state */
  	if (SCTP_GET_STATE(asoc) == SCTP_STATE_COOKIE_ECHOED) {
  		/* state change only needed when I am in right state */
  		SCTPDBG(SCTP_DEBUG_INPUT2, "moving to OPEN state\n");
  		SCTP_SET_STATE(asoc, SCTP_STATE_OPEN);
  		sctp_start_net_timers(stcb);
  		if (asoc->state & SCTP_STATE_SHUTDOWN_PENDING) {
  			sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
  					 stcb->sctp_ep, stcb, asoc->primary_destination);
  
  		}
  		/* update RTO */
  		SCTP_STAT_INCR_COUNTER32(sctps_activeestab);
  		SCTP_STAT_INCR_GAUGE32(sctps_currestab);
  		if (asoc->overall_error_count == 0) {
  			net->RTO = sctp_calculate_rto(stcb, asoc, net,
  					             &asoc->time_entered, sctp_align_safe_nocopy,
  						      SCTP_RTT_FROM_NON_DATA);
  		}
  		(void)SCTP_GETTIME_TIMEVAL(&asoc->time_entered);
  		sctp_ulp_notify(SCTP_NOTIFY_ASSOC_UP, stcb, 0, NULL, SCTP_SO_NOT_LOCKED);
  		if ((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) ||
  		    (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_IN_TCPPOOL)) {
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  			struct socket *so;
  
  #endif
  			stcb->sctp_ep->sctp_flags |= SCTP_PCB_FLAGS_CONNECTED;
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  			so = SCTP_INP_SO(stcb->sctp_ep);
  			atomic_add_int(&stcb->asoc.refcnt, 1);
  			SCTP_TCB_UNLOCK(stcb);
  			SCTP_SOCKET_LOCK(so, 1);
  			SCTP_TCB_LOCK(stcb);
  			atomic_subtract_int(&stcb->asoc.refcnt, 1);
  #endif
  			if ((stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET) == 0) {
  				soisconnected(stcb->sctp_socket);
  			}
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  			SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  		}
  		/*
  		 * since we did not send a HB make sure we don't double
  		 * things
  		 */
  		net->hb_responded = 1;
  
  		if (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET) {
  			/* We don't need to do the asconf thing,
  			 * nor hb or autoclose if the socket is closed.
  			 */
  			goto closed_socket;
  		}
  
  		sctp_timer_start(SCTP_TIMER_TYPE_HEARTBEAT, stcb->sctp_ep,
  		    stcb, net);
  
  
  		if (stcb->asoc.sctp_autoclose_ticks &&
  		    sctp_is_feature_on(stcb->sctp_ep, SCTP_PCB_FLAGS_AUTOCLOSE)) {
  			sctp_timer_start(SCTP_TIMER_TYPE_AUTOCLOSE,
  			    stcb->sctp_ep, stcb, NULL);
  		}
  		/*
  		 * send ASCONF if parameters are pending and ASCONFs are
  		 * allowed (eg. addresses changed when init/cookie echo were
  		 * in flight)
  		 */
  		if ((sctp_is_feature_on(stcb->sctp_ep, SCTP_PCB_FLAGS_DO_ASCONF)) &&
  		    (stcb->asoc.asconf_supported == 1) &&
  		    (!TAILQ_EMPTY(&stcb->asoc.asconf_queue))) {
  #ifdef SCTP_TIMER_BASED_ASCONF
  			sctp_timer_start(SCTP_TIMER_TYPE_ASCONF,
  					 stcb->sctp_ep, stcb,
  					 stcb->asoc.primary_destination);
  #else
  			sctp_send_asconf(stcb, stcb->asoc.primary_destination,
  					 SCTP_ADDR_NOT_LOCKED);
  #endif
  		}
  	}
  closed_socket:
  	/* Toss the cookie if I can */
  	sctp_toss_old_cookies(stcb, asoc);
  	if (!TAILQ_EMPTY(&asoc->sent_queue)) {
  		/* Restart the timer if we have pending data */
  		struct sctp_tmit_chunk *chk;
  
  		chk = TAILQ_FIRST(&asoc->sent_queue);
  		sctp_timer_start(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep, stcb, chk->whoTo);
  	}
  }
  
  static void
  sctp_handle_ecn_echo(struct sctp_ecne_chunk *cp,
  		     struct sctp_tcb *stcb)
  {
  	struct sctp_nets *net;
  	struct sctp_tmit_chunk *lchk;
  	struct sctp_ecne_chunk bkup;
  	uint8_t override_bit;
  	uint32_t tsn, window_data_tsn;
  	int len;
  	unsigned int pkt_cnt;
  
  	len = ntohs(cp->ch.chunk_length);
  	if ((len != sizeof(struct sctp_ecne_chunk)) &&
  	    (len != sizeof(struct old_sctp_ecne_chunk))) {
  		return;
  	}
  	if (len == sizeof(struct old_sctp_ecne_chunk)) {
  		/* Its the old format */
  		memcpy(&bkup, cp, sizeof(struct old_sctp_ecne_chunk));
  		bkup.num_pkts_since_cwr = htonl(1);
  		cp = &bkup;
  	}
  	SCTP_STAT_INCR(sctps_recvecne);
  	tsn = ntohl(cp->tsn);
  	pkt_cnt = ntohl(cp->num_pkts_since_cwr);
  	lchk = TAILQ_LAST(&stcb->asoc.send_queue, sctpchunk_listhead);
  	if (lchk == NULL) {
  		window_data_tsn = stcb->asoc.sending_seq - 1;
  	} else {
  		window_data_tsn = lchk->rec.data.TSN_seq;
  	}
  
  	/* Find where it was sent to if possible. */
  	net = NULL;
  	TAILQ_FOREACH(lchk, &stcb->asoc.sent_queue, sctp_next) {
  		if (lchk->rec.data.TSN_seq == tsn) {
  			net = lchk->whoTo;
  			net->ecn_prev_cwnd = lchk->rec.data.cwnd_at_send;
  			break;
  		}
  		if (SCTP_TSN_GT(lchk->rec.data.TSN_seq, tsn)) {
  			break;
  		}
  	}
  	if (net == NULL) {
  		/*
  		 * What to do. A previous send of a
  		 * CWR was possibly lost. See how old it is, we
  		 * may have it marked on the actual net.
  		 */
  		TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) {
  			if (tsn == net->last_cwr_tsn) {
  				/* Found him, send it off */
  				break;
  			}
  		}
  		if (net == NULL) {
  			/*
  			 * If we reach here, we need to send a special
  			 * CWR that says hey, we did this a long time
  			 * ago and you lost the response.
  			 */
  			net = TAILQ_FIRST(&stcb->asoc.nets);
  			if (net == NULL) {
  				/* TSNH */
  				return;
  			}
  			override_bit = SCTP_CWR_REDUCE_OVERRIDE;
  		} else {
  			override_bit = 0;
  		}
  	} else {
  		override_bit = 0;
  	}
  	if (SCTP_TSN_GT(tsn, net->cwr_window_tsn) &&
  	    ((override_bit&SCTP_CWR_REDUCE_OVERRIDE) == 0)) {
  		/* JRS - Use the congestion control given in the pluggable CC module */
  		stcb->asoc.cc_functions.sctp_cwnd_update_after_ecn_echo(stcb, net, 0, pkt_cnt);
  		/*
  		 * We reduce once every RTT. So we will only lower cwnd at
  		 * the next sending seq i.e. the window_data_tsn
  		 */
  		net->cwr_window_tsn = window_data_tsn;
  		net->ecn_ce_pkt_cnt += pkt_cnt;
  		net->lost_cnt = pkt_cnt;
  		net->last_cwr_tsn = tsn;
  	} else {
  		override_bit |= SCTP_CWR_IN_SAME_WINDOW;
  		if (SCTP_TSN_GT(tsn, net->last_cwr_tsn) &&
  		    ((override_bit&SCTP_CWR_REDUCE_OVERRIDE) == 0)) {
  			/*
  			 * Another loss in the same window update how
  			 * many marks/packets lost we have had.
  			 */
  			int cnt = 1;
  			if (pkt_cnt > net->lost_cnt) {
  				/* Should be the case */
  				cnt = (pkt_cnt - net->lost_cnt);
  				net->ecn_ce_pkt_cnt += cnt;
  			}
  			net->lost_cnt = pkt_cnt;
  			net->last_cwr_tsn = tsn;
  			/*
  			 * Most CC functions will ignore this call, since we are in-window
  			 * yet of the initial CE the peer saw.
  			 */
  			stcb->asoc.cc_functions.sctp_cwnd_update_after_ecn_echo(stcb, net, 1, cnt);
  		}
  	}
  	/*
  	 * We always send a CWR this way if our previous one was lost our
  	 * peer will get an update, or if it is not time again to reduce we
  	 * still get the cwr to the peer. Note we set the override when we
  	 * could not find the TSN on the chunk or the destination network.
  	 */
  	sctp_send_cwr(stcb, net, net->last_cwr_tsn, override_bit);
  }
  
  static void
  sctp_handle_ecn_cwr(struct sctp_cwr_chunk *cp, struct sctp_tcb *stcb, struct sctp_nets *net)
  {
  	/*
  	 * Here we get a CWR from the peer. We must look in the outqueue and
  	 * make sure that we have a covered ECNE in the control chunk part.
  	 * If so remove it.
  	 */
  	struct sctp_tmit_chunk *chk;
  	struct sctp_ecne_chunk *ecne;
  	int override;
  	uint32_t cwr_tsn;
  
  	cwr_tsn = ntohl(cp->tsn);
  	override = cp->ch.chunk_flags & SCTP_CWR_REDUCE_OVERRIDE;
  	TAILQ_FOREACH(chk, &stcb->asoc.control_send_queue, sctp_next) {
  		if (chk->rec.chunk_id.id != SCTP_ECN_ECHO) {
  			continue;
  		}
  		if ((override == 0) && (chk->whoTo != net)) {
  			/* Must be from the right src unless override is set */
  			continue;
  		}
  		ecne = mtod(chk->data, struct sctp_ecne_chunk *);
  		if (SCTP_TSN_GE(cwr_tsn, ntohl(ecne->tsn))) {
  			/* this covers this ECNE, we can remove it */
  			stcb->asoc.ecn_echo_cnt_onq--;
  			TAILQ_REMOVE(&stcb->asoc.control_send_queue, chk,
  			    sctp_next);
  			sctp_m_freem(chk->data);
  			chk->data = NULL;
  			stcb->asoc.ctrl_queue_cnt--;
  			sctp_free_a_chunk(stcb, chk, SCTP_SO_NOT_LOCKED);
  			if (override == 0) {
  				break;
  			}
  		}
  	}
  }
  
  static void
  sctp_handle_shutdown_complete(struct sctp_shutdown_complete_chunk *cp SCTP_UNUSED,
      struct sctp_tcb *stcb, struct sctp_nets *net)
  {
  	struct sctp_association *asoc;
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  	struct socket *so;
  #endif
  
  	SCTPDBG(SCTP_DEBUG_INPUT2,
  		"sctp_handle_shutdown_complete: handling SHUTDOWN-COMPLETE\n");
  	if (stcb == NULL)
  		return;
  
  	asoc = &stcb->asoc;
  	/* process according to association state */
  	if (SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_ACK_SENT) {
  		/* unexpected SHUTDOWN-COMPLETE... so ignore... */
  		SCTPDBG(SCTP_DEBUG_INPUT2,
  			"sctp_handle_shutdown_complete: not in SCTP_STATE_SHUTDOWN_ACK_SENT --- ignore\n");
  		SCTP_TCB_UNLOCK(stcb);
  		return;
  	}
  	/* notify upper layer protocol */
  	if (stcb->sctp_socket) {
  		sctp_ulp_notify(SCTP_NOTIFY_ASSOC_DOWN, stcb, 0, NULL, SCTP_SO_NOT_LOCKED);
  	}
  #ifdef INVARIANTS
  	if (!TAILQ_EMPTY(&asoc->send_queue) ||
  	    !TAILQ_EMPTY(&asoc->sent_queue) ||
  	    !stcb->asoc.ss_functions.sctp_ss_is_empty(stcb, asoc)) {
  		panic("Queues are not empty when handling SHUTDOWN-COMPLETE");
  	}
  #endif
  	/* stop the timer */
  	sctp_timer_stop(SCTP_TIMER_TYPE_SHUTDOWNACK, stcb->sctp_ep, stcb, net,
  	                SCTP_FROM_SCTP_INPUT + SCTP_LOC_24);
  	SCTP_STAT_INCR_COUNTER32(sctps_shutdown);
  	/* free the TCB */
  	SCTPDBG(SCTP_DEBUG_INPUT2,
  		"sctp_handle_shutdown_complete: calls free-asoc\n");
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  	so = SCTP_INP_SO(stcb->sctp_ep);
  	atomic_add_int(&stcb->asoc.refcnt, 1);
  	SCTP_TCB_UNLOCK(stcb);
  	SCTP_SOCKET_LOCK(so, 1);
  	SCTP_TCB_LOCK(stcb);
  	atomic_subtract_int(&stcb->asoc.refcnt, 1);
  #endif
  	(void)sctp_free_assoc(stcb->sctp_ep, stcb, SCTP_NORMAL_PROC,
  	                      SCTP_FROM_SCTP_INPUT + SCTP_LOC_25);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  	SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  	return;
  }
  
  static int
  process_chunk_drop(struct sctp_tcb *stcb, struct sctp_chunk_desc *desc,
      struct sctp_nets *net, uint8_t flg)
  {
  	switch (desc->chunk_type) {
  	case SCTP_DATA:
  		/* find the tsn to resend (possibly */
  	{
  		uint32_t tsn;
  		struct sctp_tmit_chunk *tp1;
  
  		tsn = ntohl(desc->tsn_ifany);
  		TAILQ_FOREACH(tp1, &stcb->asoc.sent_queue, sctp_next) {
  			if (tp1->rec.data.TSN_seq == tsn) {
  				/* found it */
  				break;
  			}
  			if (SCTP_TSN_GT(tp1->rec.data.TSN_seq, tsn)) {
  				/* not found */
  				tp1 = NULL;
  				break;
  			}
  		}
  		if (tp1 == NULL) {
  			/*
  			 * Do it the other way , aka without paying
  			 * attention to queue seq order.
  			 */
  			SCTP_STAT_INCR(sctps_pdrpdnfnd);
  			TAILQ_FOREACH(tp1, &stcb->asoc.sent_queue, sctp_next) {
  				if (tp1->rec.data.TSN_seq == tsn) {
  					/* found it */
  					break;
  				}
  			}
  		}
  		if (tp1 == NULL) {
  			SCTP_STAT_INCR(sctps_pdrptsnnf);
  		}
  		if ((tp1) && (tp1->sent < SCTP_DATAGRAM_ACKED)) {
  			uint8_t *ddp;
  
  			if (((flg & SCTP_BADCRC) == 0) &&
  			    ((flg & SCTP_FROM_MIDDLE_BOX) == 0)) {
  				return (0);
  			}
  			if ((stcb->asoc.peers_rwnd == 0) &&
  			    ((flg & SCTP_FROM_MIDDLE_BOX) == 0)) {
  				SCTP_STAT_INCR(sctps_pdrpdiwnp);
  				return (0);
  			}
  			if (stcb->asoc.peers_rwnd == 0 &&
  			    (flg & SCTP_FROM_MIDDLE_BOX)) {
  				SCTP_STAT_INCR(sctps_pdrpdizrw);
  				return (0);
  			}
  			ddp = (uint8_t *) (mtod(tp1->data, caddr_t) +
  					   sizeof(struct sctp_data_chunk));
  			{
  				unsigned int iii;
  
  				for (iii = 0; iii < sizeof(desc->data_bytes);
  				     iii++) {
  					if (ddp[iii] != desc->data_bytes[iii]) {
  						SCTP_STAT_INCR(sctps_pdrpbadd);
  						return (-1);
  					}
  				}
  			}
  
  			if (tp1->do_rtt) {
  				/*
  				 * this guy had a RTO calculation
  				 * pending on it, cancel it
  				 */
  				if (tp1->whoTo->rto_needed == 0) {
  					tp1->whoTo->rto_needed = 1;
  				}
  				tp1->do_rtt = 0;
  			}
  			SCTP_STAT_INCR(sctps_pdrpmark);
  			if (tp1->sent != SCTP_DATAGRAM_RESEND)
  				sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
  			/*
  			 * mark it as if we were doing a FR, since
  			 * we will be getting gap ack reports behind
  			 * the info from the router.
  			 */
  			tp1->rec.data.doing_fast_retransmit = 1;
  			/*
  			 * mark the tsn with what sequences can
  			 * cause a new FR.
  			 */
  			if (TAILQ_EMPTY(&stcb->asoc.send_queue)) {
  				tp1->rec.data.fast_retran_tsn = stcb->asoc.sending_seq;
  			} else {
  				tp1->rec.data.fast_retran_tsn = (TAILQ_FIRST(&stcb->asoc.send_queue))->rec.data.TSN_seq;
  			}
  
  			/* restart the timer */
  			sctp_timer_stop(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
  					stcb, tp1->whoTo,
  			                SCTP_FROM_SCTP_INPUT + SCTP_LOC_26);
  			sctp_timer_start(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
  					 stcb, tp1->whoTo);
  
  			/* fix counts and things */
  			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FLIGHT_LOGGING_ENABLE) {
  				sctp_misc_ints(SCTP_FLIGHT_LOG_DOWN_PDRP,
  					       tp1->whoTo->flight_size,
  					       tp1->book_size,
  					       (uint32_t)(uintptr_t)stcb,
  					       tp1->rec.data.TSN_seq);
  			}
  			if (tp1->sent < SCTP_DATAGRAM_RESEND) {
  				sctp_flight_size_decrease(tp1);
  				sctp_total_flight_decrease(stcb, tp1);
  			}
  			tp1->sent = SCTP_DATAGRAM_RESEND;
  		} {
  			/* audit code */
  			unsigned int audit;
  
  			audit = 0;
  			TAILQ_FOREACH(tp1, &stcb->asoc.sent_queue, sctp_next) {
  				if (tp1->sent == SCTP_DATAGRAM_RESEND)
  					audit++;
  			}
  			TAILQ_FOREACH(tp1, &stcb->asoc.control_send_queue,
  				      sctp_next) {
  				if (tp1->sent == SCTP_DATAGRAM_RESEND)
  					audit++;
  			}
  			if (audit != stcb->asoc.sent_queue_retran_cnt) {
  				SCTP_PRINTF("**Local Audit finds cnt:%d asoc cnt:%d\n",
  					    audit, stcb->asoc.sent_queue_retran_cnt);
  #ifndef SCTP_AUDITING_ENABLED
  				stcb->asoc.sent_queue_retran_cnt = audit;
  #endif
  			}
  		}
  	}
  	break;
  	case SCTP_ASCONF:
  	{
  		struct sctp_tmit_chunk *asconf;
  
  		TAILQ_FOREACH(asconf, &stcb->asoc.control_send_queue,
  			      sctp_next) {
  			if (asconf->rec.chunk_id.id == SCTP_ASCONF) {
  				break;
  			}
  		}
  		if (asconf) {
  			if (asconf->sent != SCTP_DATAGRAM_RESEND)
  				sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
  			asconf->sent = SCTP_DATAGRAM_RESEND;
  			asconf->snd_count--;
  		}
  	}
  	break;
  	case SCTP_INITIATION:
  		/* resend the INIT */
  		stcb->asoc.dropped_special_cnt++;
  		if (stcb->asoc.dropped_special_cnt < SCTP_RETRY_DROPPED_THRESH) {
  			/*
  			 * If we can get it in, in a few attempts we do
  			 * this, otherwise we let the timer fire.
  			 */
  			sctp_timer_stop(SCTP_TIMER_TYPE_INIT, stcb->sctp_ep,
  					stcb, net,
  			                SCTP_FROM_SCTP_INPUT + SCTP_LOC_27);
  			sctp_send_initiate(stcb->sctp_ep, stcb, SCTP_SO_NOT_LOCKED);
  		}
  		break;
  	case SCTP_SELECTIVE_ACK:
  	case SCTP_NR_SELECTIVE_ACK:
  		/* resend the sack */
  		sctp_send_sack(stcb, SCTP_SO_NOT_LOCKED);
  		break;
  	case SCTP_HEARTBEAT_REQUEST:
  		/* resend a demand HB */
  		if ((stcb->asoc.overall_error_count + 3) < stcb->asoc.max_send_times) {
  			/* Only retransmit if we KNOW we wont destroy the tcb */
  			sctp_send_hb(stcb, net, SCTP_SO_NOT_LOCKED);
  		}
  		break;
  	case SCTP_SHUTDOWN:
  		sctp_send_shutdown(stcb, net);
  		break;
  	case SCTP_SHUTDOWN_ACK:
  		sctp_send_shutdown_ack(stcb, net);
  		break;
  	case SCTP_COOKIE_ECHO:
  	{
  		struct sctp_tmit_chunk *cookie;
  
  		cookie = NULL;
  		TAILQ_FOREACH(cookie, &stcb->asoc.control_send_queue,
  			      sctp_next) {
  			if (cookie->rec.chunk_id.id == SCTP_COOKIE_ECHO) {
  				break;
  			}
  		}
  		if (cookie) {
  			if (cookie->sent != SCTP_DATAGRAM_RESEND)
  				sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
  			cookie->sent = SCTP_DATAGRAM_RESEND;
  			sctp_stop_all_cookie_timers(stcb);
  		}
  	}
  	break;
  	case SCTP_COOKIE_ACK:
  		sctp_send_cookie_ack(stcb);
  		break;
  	case SCTP_ASCONF_ACK:
  		/* resend last asconf ack */
  		sctp_send_asconf_ack(stcb);
  		break;
  	case SCTP_IFORWARD_CUM_TSN:
  	case SCTP_FORWARD_CUM_TSN:
  		send_forward_tsn(stcb, &stcb->asoc);
  		break;
  		/* can't do anything with these */
  	case SCTP_PACKET_DROPPED:
  	case SCTP_INITIATION_ACK:	/* this should not happen */
  	case SCTP_HEARTBEAT_ACK:
  	case SCTP_ABORT_ASSOCIATION:
  	case SCTP_OPERATION_ERROR:
  	case SCTP_SHUTDOWN_COMPLETE:
  	case SCTP_ECN_ECHO:
  	case SCTP_ECN_CWR:
  	default:
  		break;
  	}
  	return (0);
  }
  
  void
  sctp_reset_in_stream(struct sctp_tcb *stcb, uint32_t number_entries, uint16_t *list)
  {
  	uint32_t i;
  	uint16_t temp;
  
  	/*
  	 * We set things to 0xffffffff since this is the last delivered sequence
  	 * and we will be sending in 0 after the reset.
  	 */
  
  	if (number_entries) {
  		for (i = 0; i < number_entries; i++) {
  			temp = ntohs(list[i]);
  			if (temp >= stcb->asoc.streamincnt) {
  				continue;
  			}
  			stcb->asoc.strmin[temp].last_sequence_delivered = 0xffffffff;
  		}
  	} else {
  		list = NULL;
  		for (i = 0; i < stcb->asoc.streamincnt; i++) {
  			stcb->asoc.strmin[i].last_sequence_delivered = 0xffffffff;
  		}
  	}
  	sctp_ulp_notify(SCTP_NOTIFY_STR_RESET_RECV, stcb, number_entries, (void *)list, SCTP_SO_NOT_LOCKED);
  }
  
  static void
  sctp_reset_out_streams(struct sctp_tcb *stcb, uint32_t number_entries, uint16_t *list)
  {
  	uint32_t i;
  	uint16_t temp;
  
  	if (number_entries > 0) {
  		for (i = 0; i < number_entries; i++) {
  			temp = ntohs(list[i]);
  			if (temp >= stcb->asoc.streamoutcnt) {
  				/* no such stream */
  				continue;
  			}
  			stcb->asoc.strmout[temp].next_mid_ordered = 0;
  			stcb->asoc.strmout[temp].next_mid_unordered = 0;
  		}
  	} else {
  		for (i = 0; i < stcb->asoc.streamoutcnt; i++) {
  			stcb->asoc.strmout[i].next_mid_ordered = 0;
  			stcb->asoc.strmout[i].next_mid_unordered = 0;
  		}
  	}
  	sctp_ulp_notify(SCTP_NOTIFY_STR_RESET_SEND, stcb, number_entries, (void *)list, SCTP_SO_NOT_LOCKED);
  }
  
  static void
  sctp_reset_clear_pending(struct sctp_tcb *stcb, uint32_t number_entries, uint16_t *list)
  {
  	uint32_t i;
  	uint16_t temp;
  
  	if (number_entries > 0) {
  		for (i = 0; i < number_entries; i++) {
  			temp = ntohs(list[i]);
  			if (temp >= stcb->asoc.streamoutcnt) {
  				/* no such stream */
  				continue;
  			}
  			stcb->asoc.strmout[temp].state = SCTP_STREAM_OPEN;
  		}
  	} else {
  		for (i = 0; i < stcb->asoc.streamoutcnt; i++) {
  			stcb->asoc.strmout[i].state = SCTP_STREAM_OPEN;
  		}
  	}
  }
  
  
  struct sctp_stream_reset_request *
  sctp_find_stream_reset(struct sctp_tcb *stcb, uint32_t seq, struct sctp_tmit_chunk **bchk)
  {
  	struct sctp_association *asoc;
  	struct sctp_chunkhdr *ch;
  	struct sctp_stream_reset_request *r;
  	struct sctp_tmit_chunk *chk;
  	int len, clen;
  
  	asoc = &stcb->asoc;
  	if (TAILQ_EMPTY(&stcb->asoc.control_send_queue)) {
  		asoc->stream_reset_outstanding = 0;
  		return (NULL);
  	}
  	if (stcb->asoc.str_reset == NULL) {
  		asoc->stream_reset_outstanding = 0;
  		return (NULL);
  	}
  	chk = stcb->asoc.str_reset;
  	if (chk->data == NULL) {
  		return (NULL);
  	}
  	if (bchk) {
  		/* he wants a copy of the chk pointer */
  		*bchk = chk;
  	}
  	clen = chk->send_size;
  	ch = mtod(chk->data, struct sctp_chunkhdr *);
  	r = (struct sctp_stream_reset_request *)(ch + 1);
  	if (ntohl(r->request_seq) == seq) {
  		/* found it */
  		return (r);
  	}
  	len = SCTP_SIZE32(ntohs(r->ph.param_length));
  	if (clen > (len + (int)sizeof(struct sctp_chunkhdr))) {
  		/* move to the next one, there can only be a max of two */
  		r = (struct sctp_stream_reset_request *)((caddr_t)r + len);
  		if (ntohl(r->request_seq) == seq) {
  			return (r);
  		}
  	}
  	/* that seq is not here */
  	return (NULL);
  }
  
  static void
  sctp_clean_up_stream_reset(struct sctp_tcb *stcb)
  {
  	struct sctp_association *asoc;
  	struct sctp_tmit_chunk *chk = stcb->asoc.str_reset;
  
  	if (stcb->asoc.str_reset == NULL) {
  		return;
  	}
  	asoc = &stcb->asoc;
  
  	sctp_timer_stop(SCTP_TIMER_TYPE_STRRESET, stcb->sctp_ep, stcb,
  	                chk->whoTo, SCTP_FROM_SCTP_INPUT + SCTP_LOC_28);
  	TAILQ_REMOVE(&asoc->control_send_queue,
  	    chk,
  	    sctp_next);
  	if (chk->data) {
  		sctp_m_freem(chk->data);
  		chk->data = NULL;
  	}
  	asoc->ctrl_queue_cnt--;
  	sctp_free_a_chunk(stcb, chk, SCTP_SO_NOT_LOCKED);
  	/*sa_ignore NO_NULL_CHK*/
  	stcb->asoc.str_reset = NULL;
  }
  
  
  static int
  sctp_handle_stream_reset_response(struct sctp_tcb *stcb,
  				  uint32_t seq, uint32_t action,
  				  struct sctp_stream_reset_response *respin)
  {
  	uint16_t type;
  	int lparm_len;
  	struct sctp_association *asoc = &stcb->asoc;
  	struct sctp_tmit_chunk *chk;
  	struct sctp_stream_reset_request *req_param;
  	struct sctp_stream_reset_out_request *req_out_param;
  	struct sctp_stream_reset_in_request *req_in_param;
  	uint32_t number_entries;
  
  	if (asoc->stream_reset_outstanding == 0) {
  		/* duplicate */
  		return (0);
  	}
  	if (seq == stcb->asoc.str_reset_seq_out) {
  		req_param = sctp_find_stream_reset(stcb, seq, &chk);
  		if (req_param != NULL) {
  			stcb->asoc.str_reset_seq_out++;
  			type = ntohs(req_param->ph.param_type);
  			lparm_len = ntohs(req_param->ph.param_length);
  			if (type == SCTP_STR_RESET_OUT_REQUEST) {
  				int no_clear = 0;
  
  				req_out_param = (struct sctp_stream_reset_out_request *)req_param;
  				number_entries = (lparm_len - sizeof(struct sctp_stream_reset_out_request)) / sizeof(uint16_t);
  				asoc->stream_reset_out_is_outstanding = 0;
  				if (asoc->stream_reset_outstanding)
  					asoc->stream_reset_outstanding--;
  				if (action == SCTP_STREAM_RESET_RESULT_PERFORMED) {
  					/* do it */
  					sctp_reset_out_streams(stcb, number_entries, req_out_param->list_of_streams);
  				} else if (action == SCTP_STREAM_RESET_RESULT_DENIED) {
  					sctp_ulp_notify(SCTP_NOTIFY_STR_RESET_DENIED_OUT, stcb, number_entries, req_out_param->list_of_streams, SCTP_SO_NOT_LOCKED);
  				} else if (action == SCTP_STREAM_RESET_RESULT_IN_PROGRESS) {
  					/* Set it up so we don't stop retransmitting */
  					asoc->stream_reset_outstanding++;
  					stcb->asoc.str_reset_seq_out--;
  					asoc->stream_reset_out_is_outstanding = 1;
  					no_clear = 1;
  				} else {
  					sctp_ulp_notify(SCTP_NOTIFY_STR_RESET_FAILED_OUT, stcb, number_entries, req_out_param->list_of_streams, SCTP_SO_NOT_LOCKED);
  				}
  				if (no_clear == 0) {
  					sctp_reset_clear_pending(stcb, number_entries, req_out_param->list_of_streams);
  				}
  			} else if (type == SCTP_STR_RESET_IN_REQUEST) {
  				req_in_param = (struct sctp_stream_reset_in_request *)req_param;
  				number_entries = (lparm_len - sizeof(struct sctp_stream_reset_in_request)) / sizeof(uint16_t);
  				if (asoc->stream_reset_outstanding)
  					asoc->stream_reset_outstanding--;
  				if (action == SCTP_STREAM_RESET_RESULT_DENIED) {
  					sctp_ulp_notify(SCTP_NOTIFY_STR_RESET_DENIED_IN, stcb,
  							number_entries, req_in_param->list_of_streams, SCTP_SO_NOT_LOCKED);
  				} else if (action != SCTP_STREAM_RESET_RESULT_PERFORMED) {
  					sctp_ulp_notify(SCTP_NOTIFY_STR_RESET_FAILED_IN, stcb,
  							number_entries, req_in_param->list_of_streams, SCTP_SO_NOT_LOCKED);
  				}
  			} else if (type == SCTP_STR_RESET_ADD_OUT_STREAMS) {
  				/* Ok we now may have more streams */
  				int num_stream;
  
  				num_stream = stcb->asoc.strm_pending_add_size;
  				if (num_stream > (stcb->asoc.strm_realoutsize - stcb->asoc.streamoutcnt)) {
  					/* TSNH */
  					num_stream = stcb->asoc.strm_realoutsize - stcb->asoc.streamoutcnt;
  				}
  				stcb->asoc.strm_pending_add_size = 0;
  				if (asoc->stream_reset_outstanding)
  					asoc->stream_reset_outstanding--;
  				if (action == SCTP_STREAM_RESET_RESULT_PERFORMED) {
  					/* Put the new streams into effect */
  					int i;
  					for ( i = asoc->streamoutcnt; i< (asoc->streamoutcnt + num_stream); i++) {
  						asoc->strmout[i].state = SCTP_STREAM_OPEN;
  					}
  					asoc->streamoutcnt += num_stream;
  					sctp_notify_stream_reset_add(stcb, stcb->asoc.streamincnt, stcb->asoc.streamoutcnt, 0);
  				} else if (action == SCTP_STREAM_RESET_RESULT_DENIED) {
  					sctp_notify_stream_reset_add(stcb, stcb->asoc.streamincnt, stcb->asoc.streamoutcnt,
  								     SCTP_STREAM_CHANGE_DENIED);
  				} else {
  					sctp_notify_stream_reset_add(stcb, stcb->asoc.streamincnt, stcb->asoc.streamoutcnt,
  								     SCTP_STREAM_CHANGE_FAILED);
  				}
  			} else if (type == SCTP_STR_RESET_ADD_IN_STREAMS) {
  				if (asoc->stream_reset_outstanding)
  					asoc->stream_reset_outstanding--;
  				if (action == SCTP_STREAM_RESET_RESULT_DENIED) {
  					sctp_notify_stream_reset_add(stcb, stcb->asoc.streamincnt, stcb->asoc.streamoutcnt,
  								     SCTP_STREAM_CHANGE_DENIED);
  				} else if (action != SCTP_STREAM_RESET_RESULT_PERFORMED) {
  					sctp_notify_stream_reset_add(stcb, stcb->asoc.streamincnt, stcb->asoc.streamoutcnt,
  								     SCTP_STREAM_CHANGE_FAILED);
  				}
  			} else if (type == SCTP_STR_RESET_TSN_REQUEST) {
  				/**
  				 * a) Adopt the new in tsn.
  				 * b) reset the map
  				 * c) Adopt the new out-tsn
  				 */
  				struct sctp_stream_reset_response_tsn *resp;
  				struct sctp_forward_tsn_chunk fwdtsn;
  				int abort_flag = 0;
  				if (respin == NULL) {
  					/* huh ? */
  					return (0);
  				}
  				if (ntohs(respin->ph.param_length) < sizeof(struct sctp_stream_reset_response_tsn)) {
  					return (0);
  				}
  				if (action == SCTP_STREAM_RESET_RESULT_PERFORMED) {
  					resp = (struct sctp_stream_reset_response_tsn *)respin;
  					asoc->stream_reset_outstanding--;
  					fwdtsn.ch.chunk_length = htons(sizeof(struct sctp_forward_tsn_chunk));
  					fwdtsn.ch.chunk_type = SCTP_FORWARD_CUM_TSN;
  					fwdtsn.new_cumulative_tsn = htonl(ntohl(resp->senders_next_tsn) - 1);
  					sctp_handle_forward_tsn(stcb, &fwdtsn, &abort_flag, NULL, 0);
  					if (abort_flag) {
  						return (1);
  					}
  					stcb->asoc.highest_tsn_inside_map = (ntohl(resp->senders_next_tsn) - 1);
  					if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MAP_LOGGING_ENABLE) {
  						sctp_log_map(0, 7, asoc->highest_tsn_inside_map, SCTP_MAP_SLIDE_RESULT);
  					}
  
  					stcb->asoc.tsn_last_delivered = stcb->asoc.cumulative_tsn = stcb->asoc.highest_tsn_inside_map;
  					stcb->asoc.mapping_array_base_tsn = ntohl(resp->senders_next_tsn);
  					memset(stcb->asoc.mapping_array, 0, stcb->asoc.mapping_array_size);
  
  					stcb->asoc.highest_tsn_inside_nr_map = stcb->asoc.highest_tsn_inside_map;
  					memset(stcb->asoc.nr_mapping_array, 0, stcb->asoc.mapping_array_size);
  
  					stcb->asoc.sending_seq = ntohl(resp->receivers_next_tsn);
  					stcb->asoc.last_acked_seq = stcb->asoc.cumulative_tsn;
  
  					sctp_reset_out_streams(stcb, 0, (uint16_t *) NULL);
  					sctp_reset_in_stream(stcb, 0, (uint16_t *) NULL);
  					sctp_notify_stream_reset_tsn(stcb, stcb->asoc.sending_seq, (stcb->asoc.mapping_array_base_tsn + 1), 0);
  				} else if (action == SCTP_STREAM_RESET_RESULT_DENIED) {
  					sctp_notify_stream_reset_tsn(stcb, stcb->asoc.sending_seq, (stcb->asoc.mapping_array_base_tsn + 1),
  								     SCTP_ASSOC_RESET_DENIED);
  				} else {
  					sctp_notify_stream_reset_tsn(stcb, stcb->asoc.sending_seq, (stcb->asoc.mapping_array_base_tsn + 1),
  								     SCTP_ASSOC_RESET_FAILED);
  				}
  			}
  			/* get rid of the request and get the request flags */
  			if (asoc->stream_reset_outstanding == 0) {
  				sctp_clean_up_stream_reset(stcb);
  			}
  		}
  	}
  	if (asoc->stream_reset_outstanding == 0) {
  		sctp_send_stream_reset_out_if_possible(stcb, SCTP_SO_NOT_LOCKED);
  	}
  	return (0);
  }
  
  static void
  sctp_handle_str_reset_request_in(struct sctp_tcb *stcb,
      struct sctp_tmit_chunk *chk,
      struct sctp_stream_reset_in_request *req, int trunc)
  {
  	uint32_t seq;
  	int len, i;
  	int number_entries;
  	uint16_t temp;
  
  	/*
  	 * peer wants me to send a str-reset to him for my outgoing seq's if
  	 * seq_in is right.
  	 */
  	struct sctp_association *asoc = &stcb->asoc;
  
  	seq = ntohl(req->request_seq);
  	if (asoc->str_reset_seq_in == seq) {
  		asoc->last_reset_action[1] = asoc->last_reset_action[0];
  		if (!(asoc->local_strreset_support & SCTP_ENABLE_RESET_STREAM_REQ)) {
  			asoc->last_reset_action[0] = SCTP_STREAM_RESET_RESULT_DENIED;
  		} else if (trunc) {
  			/* Can't do it, since they exceeded our buffer size  */
  			asoc->last_reset_action[0] = SCTP_STREAM_RESET_RESULT_DENIED;
  		} else if (stcb->asoc.stream_reset_out_is_outstanding == 0) {
  			len = ntohs(req->ph.param_length);
  			number_entries = ((len - sizeof(struct sctp_stream_reset_in_request)) / sizeof(uint16_t));
  			if (number_entries) {
  				for (i = 0; i < number_entries; i++) {
  					temp = ntohs(req->list_of_streams[i]);
  					if (temp >= stcb->asoc.streamoutcnt) {
  						asoc->last_reset_action[0] = SCTP_STREAM_RESET_RESULT_DENIED;
  						goto bad_boy;
  					}
  					req->list_of_streams[i] = temp;
  				}
  				for (i = 0; i < number_entries; i++) {
  					if (stcb->asoc.strmout[req->list_of_streams[i]].state == SCTP_STREAM_OPEN) {
  						stcb->asoc.strmout[req->list_of_streams[i]].state = SCTP_STREAM_RESET_PENDING;
  					}
  				}
  			} else {
  				/* Its all */
  				for (i = 0; i < stcb->asoc.streamoutcnt; i++) {
  					if (stcb->asoc.strmout[i].state == SCTP_STREAM_OPEN)
  						stcb->asoc.strmout[i].state = SCTP_STREAM_RESET_PENDING;
  				}
  			}
  			asoc->last_reset_action[0] = SCTP_STREAM_RESET_RESULT_PERFORMED;
  		} else {
  			/* Can't do it, since we have sent one out */
  			asoc->last_reset_action[0] = SCTP_STREAM_RESET_RESULT_ERR_IN_PROGRESS;
  		}
  	bad_boy:
  		sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[0]);
  		asoc->str_reset_seq_in++;
  	} else if (asoc->str_reset_seq_in - 1 == seq) {
  		sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[0]);
  	} else if (asoc->str_reset_seq_in - 2 == seq) {
  		sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[1]);
  	} else {
  		sctp_add_stream_reset_result(chk, seq, SCTP_STREAM_RESET_RESULT_ERR_BAD_SEQNO);
  	}
  	sctp_send_stream_reset_out_if_possible(stcb, SCTP_SO_NOT_LOCKED);
  }
  
  static int
  sctp_handle_str_reset_request_tsn(struct sctp_tcb *stcb,
      struct sctp_tmit_chunk *chk,
      struct sctp_stream_reset_tsn_request *req)
  {
  	/* reset all in and out and update the tsn */
  	/*
  	 * A) reset my str-seq's on in and out. B) Select a receive next,
  	 * and set cum-ack to it. Also process this selected number as a
  	 * fwd-tsn as well. C) set in the response my next sending seq.
  	 */
  	struct sctp_forward_tsn_chunk fwdtsn;
  	struct sctp_association *asoc = &stcb->asoc;
  	int abort_flag = 0;
  	uint32_t seq;
  
  	seq = ntohl(req->request_seq);
  	if (asoc->str_reset_seq_in == seq) {
  		asoc->last_reset_action[1] = stcb->asoc.last_reset_action[0];
  		if (!(asoc->local_strreset_support & SCTP_ENABLE_CHANGE_ASSOC_REQ)) {
  			asoc->last_reset_action[0] = SCTP_STREAM_RESET_RESULT_DENIED;
  		} else {
  			fwdtsn.ch.chunk_length = htons(sizeof(struct sctp_forward_tsn_chunk));
  			fwdtsn.ch.chunk_type = SCTP_FORWARD_CUM_TSN;
  			fwdtsn.ch.chunk_flags = 0;
  			fwdtsn.new_cumulative_tsn = htonl(stcb->asoc.highest_tsn_inside_map + 1);
  			sctp_handle_forward_tsn(stcb, &fwdtsn, &abort_flag, NULL, 0);
  			if (abort_flag) {
  				return (1);
  			}
  			asoc->highest_tsn_inside_map += SCTP_STREAM_RESET_TSN_DELTA;
  			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MAP_LOGGING_ENABLE) {
  				sctp_log_map(0, 10, asoc->highest_tsn_inside_map, SCTP_MAP_SLIDE_RESULT);
  			}
  			asoc->tsn_last_delivered = asoc->cumulative_tsn = asoc->highest_tsn_inside_map;
  			asoc->mapping_array_base_tsn = asoc->highest_tsn_inside_map + 1;
  			memset(asoc->mapping_array, 0, asoc->mapping_array_size);
  			asoc->highest_tsn_inside_nr_map = asoc->highest_tsn_inside_map;
  			memset(asoc->nr_mapping_array, 0, asoc->mapping_array_size);
  			atomic_add_int(&asoc->sending_seq, 1);
  			/* save off historical data for retrans */
  			asoc->last_sending_seq[1] = asoc->last_sending_seq[0];
  			asoc->last_sending_seq[0] = asoc->sending_seq;
  			asoc->last_base_tsnsent[1] = asoc->last_base_tsnsent[0];
  			asoc->last_base_tsnsent[0] = asoc->mapping_array_base_tsn;
  			sctp_reset_out_streams(stcb, 0, (uint16_t *) NULL);
  			sctp_reset_in_stream(stcb, 0, (uint16_t *) NULL);
  			asoc->last_reset_action[0] = SCTP_STREAM_RESET_RESULT_PERFORMED;
  			sctp_notify_stream_reset_tsn(stcb, asoc->sending_seq, (asoc->mapping_array_base_tsn + 1), 0);
  		}
  		sctp_add_stream_reset_result_tsn(chk, seq, asoc->last_reset_action[0],
  		                                 asoc->last_sending_seq[0], asoc->last_base_tsnsent[0]);
  		asoc->str_reset_seq_in++;
  	} else if (asoc->str_reset_seq_in - 1 == seq) {
  		sctp_add_stream_reset_result_tsn(chk, seq, asoc->last_reset_action[0],
  		                                 asoc->last_sending_seq[0], asoc->last_base_tsnsent[0]);
  	} else if (asoc->str_reset_seq_in - 2 == seq) {
  		sctp_add_stream_reset_result_tsn(chk, seq, asoc->last_reset_action[1],
  		                                 asoc->last_sending_seq[1], asoc->last_base_tsnsent[1]);
  	} else {
  		sctp_add_stream_reset_result(chk, seq, SCTP_STREAM_RESET_RESULT_ERR_BAD_SEQNO);
  	}
  	return (0);
  }
  
  static void
  sctp_handle_str_reset_request_out(struct sctp_tcb *stcb,
      struct sctp_tmit_chunk *chk,
      struct sctp_stream_reset_out_request *req, int trunc)
  {
  	uint32_t seq, tsn;
  	int number_entries, len;
  	struct sctp_association *asoc = &stcb->asoc;
  
  	seq = ntohl(req->request_seq);
  
  	/* now if its not a duplicate we process it */
  	if (asoc->str_reset_seq_in == seq) {
  		len = ntohs(req->ph.param_length);
  		number_entries = ((len - sizeof(struct sctp_stream_reset_out_request)) / sizeof(uint16_t));
  		/*
  		 * the sender is resetting, handle the list issue.. we must
  		 * a) verify if we can do the reset, if so no problem b) If
  		 * we can't do the reset we must copy the request. c) queue
  		 * it, and setup the data in processor to trigger it off
  		 * when needed and dequeue all the queued data.
  		 */
  		tsn = ntohl(req->send_reset_at_tsn);
  
  		/* move the reset action back one */
  		asoc->last_reset_action[1] = asoc->last_reset_action[0];
  		if (!(asoc->local_strreset_support & SCTP_ENABLE_RESET_STREAM_REQ)) {
  			asoc->last_reset_action[0] = SCTP_STREAM_RESET_RESULT_DENIED;
  		} else if (trunc) {
  			asoc->last_reset_action[0] = SCTP_STREAM_RESET_RESULT_DENIED;
  		} else if (SCTP_TSN_GE(asoc->cumulative_tsn, tsn)) {
  			/* we can do it now */
  			sctp_reset_in_stream(stcb, number_entries, req->list_of_streams);
  			asoc->last_reset_action[0] = SCTP_STREAM_RESET_RESULT_PERFORMED;
  		} else {
  			/*
  			 * we must queue it up and thus wait for the TSN's
  			 * to arrive that are at or before tsn
  			 */
  			struct sctp_stream_reset_list *liste;
  			int siz;
  
  			siz = sizeof(struct sctp_stream_reset_list) + (number_entries * sizeof(uint16_t));
  			SCTP_MALLOC(liste, struct sctp_stream_reset_list *,
  				    siz, SCTP_M_STRESET);
  			if (liste == NULL) {
  				/* gak out of memory */
  				asoc->last_reset_action[0] = SCTP_STREAM_RESET_RESULT_DENIED;
  				sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[0]);
  				return;
  			}
  			liste->seq = seq;
  			liste->tsn = tsn;
  			liste->number_entries = number_entries;
  			memcpy(&liste->list_of_streams, req->list_of_streams, number_entries * sizeof(uint16_t));
  			TAILQ_INSERT_TAIL(&asoc->resetHead, liste, next_resp);
  			asoc->last_reset_action[0] = SCTP_STREAM_RESET_RESULT_IN_PROGRESS;
  		}
  		sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[0]);
  		asoc->str_reset_seq_in++;
  	} else if ((asoc->str_reset_seq_in - 1) == seq) {
  		/*
  		 * one seq back, just echo back last action since my
  		 * response was lost.
  		 */
  		sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[0]);
  	} else if ((asoc->str_reset_seq_in - 2) == seq) {
  		/*
  		 * two seq back, just echo back last action since my
  		 * response was lost.
  		 */
  		sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[1]);
  	} else {
  		sctp_add_stream_reset_result(chk, seq, SCTP_STREAM_RESET_RESULT_ERR_BAD_SEQNO);
  	}
  }
  
  static void
  sctp_handle_str_reset_add_strm(struct sctp_tcb *stcb, struct sctp_tmit_chunk *chk,
  			       struct sctp_stream_reset_add_strm  *str_add)
  {
  	/*
  	 * Peer is requesting to add more streams.
  	 * If its within our max-streams we will
  	 * allow it.
  	 */
  	uint32_t num_stream, i;
  	uint32_t seq;
  	struct sctp_association *asoc = &stcb->asoc;
  	struct sctp_queued_to_read *ctl, *nctl;
  
  	/* Get the number. */
  	seq = ntohl(str_add->request_seq);
  	num_stream = ntohs(str_add->number_of_streams);
  	/* Now what would be the new total? */
  	if (asoc->str_reset_seq_in == seq) {
  		num_stream += stcb->asoc.streamincnt;
  		stcb->asoc.last_reset_action[1] = stcb->asoc.last_reset_action[0];
  		if (!(asoc->local_strreset_support & SCTP_ENABLE_CHANGE_ASSOC_REQ)) {
  			asoc->last_reset_action[0] = SCTP_STREAM_RESET_RESULT_DENIED;
  		} else if ((num_stream > stcb->asoc.max_inbound_streams) ||
  		           (num_stream > 0xffff)) {
  			/* We must reject it they ask for to many */
    denied:
  			stcb->asoc.last_reset_action[0] = SCTP_STREAM_RESET_RESULT_DENIED;
  		} else {
  			/* Ok, we can do that :-) */
  			struct sctp_stream_in *oldstrm;
  
  			/* save off the old */
  			oldstrm = stcb->asoc.strmin;
  			SCTP_MALLOC(stcb->asoc.strmin, struct sctp_stream_in *,
  			            (num_stream * sizeof(struct sctp_stream_in)),
  			            SCTP_M_STRMI);
  			if (stcb->asoc.strmin == NULL) {
  				stcb->asoc.strmin = oldstrm;
  				goto denied;
  			}
  			/* copy off the old data */
  			for (i = 0; i < stcb->asoc.streamincnt; i++) {
  				TAILQ_INIT(&stcb->asoc.strmin[i].inqueue);
  				TAILQ_INIT(&stcb->asoc.strmin[i].uno_inqueue);
  				stcb->asoc.strmin[i].stream_no = i;
  				stcb->asoc.strmin[i].last_sequence_delivered = oldstrm[i].last_sequence_delivered;
  				stcb->asoc.strmin[i].delivery_started = oldstrm[i].delivery_started;
  				stcb->asoc.strmin[i].pd_api_started = oldstrm[i].pd_api_started;
  				/* now anything on those queues? */
  				TAILQ_FOREACH_SAFE(ctl, &oldstrm[i].inqueue, next_instrm, nctl) {
  					TAILQ_REMOVE(&oldstrm[i].inqueue, ctl, next_instrm);
  					TAILQ_INSERT_TAIL(&stcb->asoc.strmin[i].inqueue, ctl, next_instrm);
  				}
  				TAILQ_FOREACH_SAFE(ctl, &oldstrm[i].uno_inqueue, next_instrm, nctl) {
  					TAILQ_REMOVE(&oldstrm[i].uno_inqueue, ctl, next_instrm);
  					TAILQ_INSERT_TAIL(&stcb->asoc.strmin[i].uno_inqueue, ctl, next_instrm);
  				}
  			}
  			/* Init the new streams */
  			for (i = stcb->asoc.streamincnt; i < num_stream; i++) {
  				TAILQ_INIT(&stcb->asoc.strmin[i].inqueue);
  				TAILQ_INIT(&stcb->asoc.strmin[i].uno_inqueue);
  				stcb->asoc.strmin[i].stream_no = i;
  				stcb->asoc.strmin[i].last_sequence_delivered = 0xffffffff;
  				stcb->asoc.strmin[i].pd_api_started = 0;
  				stcb->asoc.strmin[i].delivery_started = 0;
  			}
  			SCTP_FREE(oldstrm, SCTP_M_STRMI);
  			/* update the size */
  			stcb->asoc.streamincnt = num_stream;
  			stcb->asoc.last_reset_action[0] = SCTP_STREAM_RESET_RESULT_PERFORMED;
  			sctp_notify_stream_reset_add(stcb, stcb->asoc.streamincnt, stcb->asoc.streamoutcnt, 0);
  		}
  		sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[0]);
  		asoc->str_reset_seq_in++;
  	} else if ((asoc->str_reset_seq_in - 1) == seq) {
  		/*
  		 * one seq back, just echo back last action since my
  		 * response was lost.
  		 */
  		sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[0]);
  	} else if ((asoc->str_reset_seq_in - 2) == seq) {
  		/*
  		 * two seq back, just echo back last action since my
  		 * response was lost.
  		 */
  		sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[1]);
  	} else {
  		sctp_add_stream_reset_result(chk, seq, SCTP_STREAM_RESET_RESULT_ERR_BAD_SEQNO);
  
  	}
  }
  
  static void
  sctp_handle_str_reset_add_out_strm(struct sctp_tcb *stcb, struct sctp_tmit_chunk *chk,
  				   struct sctp_stream_reset_add_strm  *str_add)
  {
  	/*
  	 * Peer is requesting to add more streams.
  	 * If its within our max-streams we will
  	 * allow it.
  	 */
  	uint16_t num_stream;
  	uint32_t seq;
  	struct sctp_association *asoc = &stcb->asoc;
  
  	/* Get the number. */
  	seq = ntohl(str_add->request_seq);
  	num_stream = ntohs(str_add->number_of_streams);
  	/* Now what would be the new total? */
  	if (asoc->str_reset_seq_in == seq) {
  		stcb->asoc.last_reset_action[1] = stcb->asoc.last_reset_action[0];
  		if (!(asoc->local_strreset_support & SCTP_ENABLE_CHANGE_ASSOC_REQ)) {
  			asoc->last_reset_action[0] = SCTP_STREAM_RESET_RESULT_DENIED;
  		} else if (stcb->asoc.stream_reset_outstanding) {
  			/* We must reject it we have something pending */
  			stcb->asoc.last_reset_action[0] = SCTP_STREAM_RESET_RESULT_ERR_IN_PROGRESS;
  		} else {
  			/* Ok, we can do that :-) */
  			int mychk;
  			mychk = stcb->asoc.streamoutcnt;
  			mychk += num_stream;
  			if (mychk < 0x10000) {
  				stcb->asoc.last_reset_action[0] = SCTP_STREAM_RESET_RESULT_PERFORMED;
  				if (sctp_send_str_reset_req(stcb, 0, NULL, 0, 0, 1, num_stream, 0, 1)) {
  					stcb->asoc.last_reset_action[0] = SCTP_STREAM_RESET_RESULT_DENIED;
  				}
  			} else {
  				stcb->asoc.last_reset_action[0] = SCTP_STREAM_RESET_RESULT_DENIED;
  			}
  		}
  		sctp_add_stream_reset_result(chk, seq, stcb->asoc.last_reset_action[0]);
  		asoc->str_reset_seq_in++;
  	} else if ((asoc->str_reset_seq_in - 1) == seq) {
  		/*
  		 * one seq back, just echo back last action since my
  		 * response was lost.
  		 */
  		sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[0]);
  	} else if ((asoc->str_reset_seq_in - 2) == seq) {
  		/*
  		 * two seq back, just echo back last action since my
  		 * response was lost.
  		 */
  		sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[1]);
  	} else {
  		sctp_add_stream_reset_result(chk, seq, SCTP_STREAM_RESET_RESULT_ERR_BAD_SEQNO);
  	}
  }
  
  #if !defined(__Panda__)
  #ifdef __GNUC__
  __attribute__ ((noinline))
  #endif
  #endif
  static int
  sctp_handle_stream_reset(struct sctp_tcb *stcb, struct mbuf *m, int offset,
  			 struct sctp_chunkhdr *ch_req)
  {
  	uint16_t remaining_length, param_len, ptype;
  	struct sctp_paramhdr pstore;
  	uint8_t cstore[SCTP_CHUNK_BUFFER_SIZE];
  	uint32_t seq = 0;
  	int num_req = 0;
  	int trunc = 0;
  	struct sctp_tmit_chunk *chk;
  	struct sctp_chunkhdr *ch;
  	struct sctp_paramhdr *ph;
  	int ret_code = 0;
  	int num_param = 0;
  
  	/* now it may be a reset or a reset-response */
  	remaining_length = ntohs(ch_req->chunk_length) - sizeof(struct sctp_chunkhdr);
  
  	/* setup for adding the response */
  	sctp_alloc_a_chunk(stcb, chk);
  	if (chk == NULL) {
  		return (ret_code);
  	}
  	chk->copy_by_ref = 0;
  	chk->rec.chunk_id.id = SCTP_STREAM_RESET;
  	chk->rec.chunk_id.can_take_data = 0;
  	chk->flags = 0;
  	chk->asoc = &stcb->asoc;
  	chk->no_fr_allowed = 0;
  	chk->book_size = chk->send_size = sizeof(struct sctp_chunkhdr);
  	chk->book_size_scale = 0;
  	chk->data = sctp_get_mbuf_for_msg(MCLBYTES, 0, M_NOWAIT, 1, MT_DATA);
  	if (chk->data == NULL) {
  	strres_nochunk:
  		if (chk->data) {
  			sctp_m_freem(chk->data);
  			chk->data = NULL;
  		}
  		sctp_free_a_chunk(stcb, chk, SCTP_SO_NOT_LOCKED);
  		return (ret_code);
  	}
  	SCTP_BUF_RESV_UF(chk->data, SCTP_MIN_OVERHEAD);
  
  	/* setup chunk parameters */
  	chk->sent = SCTP_DATAGRAM_UNSENT;
  	chk->snd_count = 0;
  	chk->whoTo = NULL;
  
  	ch = mtod(chk->data, struct sctp_chunkhdr *);
  	ch->chunk_type = SCTP_STREAM_RESET;
  	ch->chunk_flags = 0;
  	ch->chunk_length = htons(chk->send_size);
  	SCTP_BUF_LEN(chk->data) = SCTP_SIZE32(chk->send_size);
  	offset += sizeof(struct sctp_chunkhdr);
  	while (remaining_length >= sizeof(struct sctp_paramhdr)) {
  		ph = (struct sctp_paramhdr *)sctp_m_getptr(m, offset, sizeof(pstore), (uint8_t *)&pstore);
  		if (ph == NULL) {
  			/* TSNH */
  			break;
  		}
  		param_len = ntohs(ph->param_length);
  		if ((param_len > remaining_length) ||
  		    (param_len < (sizeof(struct sctp_paramhdr) + sizeof(uint32_t)))) {
  			/* bad parameter length */
  			break;
  		}
  		ph = (struct sctp_paramhdr *)sctp_m_getptr(m, offset, min(param_len, sizeof(cstore)),
  							   (uint8_t *)&cstore);
  		if (ph == NULL) {
  			/* TSNH */
  			break;
  		}
  		ptype = ntohs(ph->param_type);
  		num_param++;
  		if (param_len > sizeof(cstore)) {
  			trunc = 1;
  		} else {
  			trunc = 0;
  		}
  		if (num_param > SCTP_MAX_RESET_PARAMS) {
  			/* hit the max of parameters already sorry.. */
  			break;
  		}
  		if (ptype == SCTP_STR_RESET_OUT_REQUEST) {
  			struct sctp_stream_reset_out_request *req_out;
  
  			if (param_len < sizeof(struct sctp_stream_reset_out_request)) {
  				break;
  			}
  			req_out = (struct sctp_stream_reset_out_request *)ph;
  			num_req++;
  			if (stcb->asoc.stream_reset_outstanding) {
  				seq = ntohl(req_out->response_seq);
  				if (seq == stcb->asoc.str_reset_seq_out) {
  					/* implicit ack */
  					(void)sctp_handle_stream_reset_response(stcb, seq, SCTP_STREAM_RESET_RESULT_PERFORMED, NULL);
  				}
  			}
  			sctp_handle_str_reset_request_out(stcb, chk, req_out, trunc);
  		} else if (ptype == SCTP_STR_RESET_ADD_OUT_STREAMS) {
  			struct sctp_stream_reset_add_strm  *str_add;
  
  			if (param_len < sizeof(struct sctp_stream_reset_add_strm)) {
  				break;
  			}
  			str_add = (struct sctp_stream_reset_add_strm  *)ph;
  			num_req++;
  			sctp_handle_str_reset_add_strm(stcb, chk, str_add);
  		} else if (ptype == SCTP_STR_RESET_ADD_IN_STREAMS) {
  			struct sctp_stream_reset_add_strm  *str_add;
  
  			if (param_len < sizeof(struct sctp_stream_reset_add_strm)) {
  				break;
  			}
  			str_add = (struct sctp_stream_reset_add_strm  *)ph;
  			num_req++;
  			sctp_handle_str_reset_add_out_strm(stcb, chk, str_add);
  		} else if (ptype == SCTP_STR_RESET_IN_REQUEST) {
  			struct sctp_stream_reset_in_request *req_in;
  
  			num_req++;
  			req_in = (struct sctp_stream_reset_in_request *)ph;
  			sctp_handle_str_reset_request_in(stcb, chk, req_in, trunc);
  		} else if (ptype == SCTP_STR_RESET_TSN_REQUEST) {
  			struct sctp_stream_reset_tsn_request *req_tsn;
  
  			num_req++;
  			req_tsn = (struct sctp_stream_reset_tsn_request *)ph;
  			if (sctp_handle_str_reset_request_tsn(stcb, chk, req_tsn)) {
  				ret_code = 1;
  				goto strres_nochunk;
  			}
  			/* no more */
  			break;
  		} else if (ptype == SCTP_STR_RESET_RESPONSE) {
  			struct sctp_stream_reset_response *resp;
  			uint32_t result;
  
  			if (param_len < sizeof(struct sctp_stream_reset_response)) {
  				break;
  			}
  			resp = (struct sctp_stream_reset_response *)ph;
  			seq = ntohl(resp->response_seq);
  			result = ntohl(resp->result);
  			if (sctp_handle_stream_reset_response(stcb, seq, result, resp)) {
  				ret_code = 1;
  				goto strres_nochunk;
  			}
  		} else {
  			break;
  		}
  		offset += SCTP_SIZE32(param_len);
  		if (remaining_length >= SCTP_SIZE32(param_len)) {
  			remaining_length -= SCTP_SIZE32(param_len);
  		} else {
  			remaining_length = 0;
  		}
  	}
  	if (num_req == 0) {
  		/* we have no response free the stuff */
  		goto strres_nochunk;
  	}
  	/* ok we have a chunk to link in */
  	TAILQ_INSERT_TAIL(&stcb->asoc.control_send_queue,
  			  chk,
  			  sctp_next);
  	stcb->asoc.ctrl_queue_cnt++;
  	return (ret_code);
  }
  
  /*
   * Handle a router or endpoints report of a packet loss, there are two ways
   * to handle this, either we get the whole packet and must disect it
   * ourselves (possibly with truncation and or corruption) or it is a summary
   * from a middle box that did the disectting for us.
   */
  static void
  sctp_handle_packet_dropped(struct sctp_pktdrop_chunk *cp,
      struct sctp_tcb *stcb, struct sctp_nets *net, uint32_t limit)
  {
  	uint32_t bottle_bw, on_queue;
  	uint16_t trunc_len;
  	unsigned int chlen;
  	unsigned int at;
  	struct sctp_chunk_desc desc;
  	struct sctp_chunkhdr *ch;
  
  	chlen = ntohs(cp->ch.chunk_length);
  	chlen -= sizeof(struct sctp_pktdrop_chunk);
  	/* XXX possible chlen underflow */
  	if (chlen == 0) {
  		ch = NULL;
  		if (cp->ch.chunk_flags & SCTP_FROM_MIDDLE_BOX)
  			SCTP_STAT_INCR(sctps_pdrpbwrpt);
  	} else {
  		ch = (struct sctp_chunkhdr *)(cp->data + sizeof(struct sctphdr));
  		chlen -= sizeof(struct sctphdr);
  		/* XXX possible chlen underflow */
  		memset(&desc, 0, sizeof(desc));
  	}
  	trunc_len = (uint16_t) ntohs(cp->trunc_len);
  	if (trunc_len > limit) {
  		trunc_len = limit;
  	}
  
  	/* now the chunks themselves */
  	while ((ch != NULL) && (chlen >= sizeof(struct sctp_chunkhdr))) {
  		desc.chunk_type = ch->chunk_type;
  		/* get amount we need to move */
  		at = ntohs(ch->chunk_length);
  		if (at < sizeof(struct sctp_chunkhdr)) {
  			/* corrupt chunk, maybe at the end? */
  			SCTP_STAT_INCR(sctps_pdrpcrupt);
  			break;
  		}
  		if (trunc_len == 0) {
  			/* we are supposed to have all of it */
  			if (at > chlen) {
  				/* corrupt skip it */
  				SCTP_STAT_INCR(sctps_pdrpcrupt);
  				break;
  			}
  		} else {
  			/* is there enough of it left ? */
  			if (desc.chunk_type == SCTP_DATA) {
  				if (chlen < (sizeof(struct sctp_data_chunk) +
  				    sizeof(desc.data_bytes))) {
  					break;
  				}
  			} else {
  				if (chlen < sizeof(struct sctp_chunkhdr)) {
  					break;
  				}
  			}
  		}
  		if (desc.chunk_type == SCTP_DATA) {
  			/* can we get out the tsn? */
  			if ((cp->ch.chunk_flags & SCTP_FROM_MIDDLE_BOX))
  				SCTP_STAT_INCR(sctps_pdrpmbda);
  
  			if (chlen >= (sizeof(struct sctp_data_chunk) + sizeof(uint32_t))) {
  				/* yep */
  				struct sctp_data_chunk *dcp;
  				uint8_t *ddp;
  				unsigned int iii;
  
  				dcp = (struct sctp_data_chunk *)ch;
  				ddp = (uint8_t *) (dcp + 1);
  				for (iii = 0; iii < sizeof(desc.data_bytes); iii++) {
  					desc.data_bytes[iii] = ddp[iii];
  				}
  				desc.tsn_ifany = dcp->dp.tsn;
  			} else {
  				/* nope we are done. */
  				SCTP_STAT_INCR(sctps_pdrpnedat);
  				break;
  			}
  		} else {
  			if ((cp->ch.chunk_flags & SCTP_FROM_MIDDLE_BOX))
  				SCTP_STAT_INCR(sctps_pdrpmbct);
  		}
  
  		if (process_chunk_drop(stcb, &desc, net, cp->ch.chunk_flags)) {
  			SCTP_STAT_INCR(sctps_pdrppdbrk);
  			break;
  		}
  		if (SCTP_SIZE32(at) > chlen) {
  			break;
  		}
  		chlen -= SCTP_SIZE32(at);
  		if (chlen < sizeof(struct sctp_chunkhdr)) {
  			/* done, none left */
  			break;
  		}
  		ch = (struct sctp_chunkhdr *)((caddr_t)ch + SCTP_SIZE32(at));
  	}
  	/* Now update any rwnd --- possibly */
  	if ((cp->ch.chunk_flags & SCTP_FROM_MIDDLE_BOX) == 0) {
  		/* From a peer, we get a rwnd report */
  		uint32_t a_rwnd;
  
  		SCTP_STAT_INCR(sctps_pdrpfehos);
  
  		bottle_bw = ntohl(cp->bottle_bw);
  		on_queue = ntohl(cp->current_onq);
  		if (bottle_bw && on_queue) {
  			/* a rwnd report is in here */
  			if (bottle_bw > on_queue)
  				a_rwnd = bottle_bw - on_queue;
  			else
  				a_rwnd = 0;
  
  			if (a_rwnd == 0)
  				stcb->asoc.peers_rwnd = 0;
  			else {
  				if (a_rwnd > stcb->asoc.total_flight) {
  					stcb->asoc.peers_rwnd =
  					    a_rwnd - stcb->asoc.total_flight;
  				} else {
  					stcb->asoc.peers_rwnd = 0;
  				}
  				if (stcb->asoc.peers_rwnd <
  				    stcb->sctp_ep->sctp_ep.sctp_sws_sender) {
  					/* SWS sender side engages */
  					stcb->asoc.peers_rwnd = 0;
  				}
  			}
  		}
  	} else {
  		SCTP_STAT_INCR(sctps_pdrpfmbox);
  	}
  
  	/* now middle boxes in sat networks get a cwnd bump */
  	if ((cp->ch.chunk_flags & SCTP_FROM_MIDDLE_BOX) &&
  	    (stcb->asoc.sat_t3_loss_recovery == 0) &&
  	    (stcb->asoc.sat_network)) {
  		/*
  		 * This is debatable but for sat networks it makes sense
  		 * Note if a T3 timer has went off, we will prohibit any
  		 * changes to cwnd until we exit the t3 loss recovery.
  		 */
  		stcb->asoc.cc_functions.sctp_cwnd_update_after_packet_dropped(stcb,
  			net, cp, &bottle_bw, &on_queue);
  	}
  }
  
  /*
   * handles all control chunks in a packet inputs: - m: mbuf chain, assumed to
   * still contain IP/SCTP header - stcb: is the tcb found for this packet -
   * offset: offset into the mbuf chain to first chunkhdr - length: is the
   * length of the complete packet outputs: - length: modified to remaining
   * length after control processing - netp: modified to new sctp_nets after
   * cookie-echo processing - return NULL to discard the packet (ie. no asoc,
   * bad packet,...) otherwise return the tcb for this packet
   */
  #if !defined(__Panda__)
  #ifdef __GNUC__
  __attribute__ ((noinline))
  #endif
  #endif
  static struct sctp_tcb *
  sctp_process_control(struct mbuf *m, int iphlen, int *offset, int length,
      struct sockaddr *src, struct sockaddr *dst,
      struct sctphdr *sh, struct sctp_chunkhdr *ch, struct sctp_inpcb *inp,
      struct sctp_tcb *stcb, struct sctp_nets **netp, int *fwd_tsn_seen,
  #if defined(__FreeBSD__)
      uint8_t mflowtype, uint32_t mflowid, uint16_t fibnum,
  #endif
      uint32_t vrf_id, uint16_t port)
  {
  	struct sctp_association *asoc;
  	struct mbuf *op_err;
  	char msg[SCTP_DIAG_INFO_LEN];
  	uint32_t vtag_in;
  	int num_chunks = 0;	/* number of control chunks processed */
  	uint32_t chk_length;
  	int ret;
  	int abort_no_unlock = 0;
  	int ecne_seen = 0;
  	/*
  	 * How big should this be, and should it be alloc'd? Lets try the
  	 * d-mtu-ceiling for now (2k) and that should hopefully work ...
  	 * until we get into jumbo grams and such..
  	 */
  	uint8_t chunk_buf[SCTP_CHUNK_BUFFER_SIZE];
  	struct sctp_tcb *locked_tcb = stcb;
  	int got_auth = 0;
  	uint32_t auth_offset = 0, auth_len = 0;
  	int auth_skipped = 0;
  	int asconf_cnt = 0;
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  	struct socket *so;
  #endif
  
  	SCTPDBG(SCTP_DEBUG_INPUT1, "sctp_process_control: iphlen=%u, offset=%u, length=%u stcb:%p\n",
  		iphlen, *offset, length, (void *)stcb);
  
  	/* validate chunk header length... */
  	if (ntohs(ch->chunk_length) < sizeof(*ch)) {
  		SCTPDBG(SCTP_DEBUG_INPUT1, "Invalid header length %d\n",
  			ntohs(ch->chunk_length));
  		if (locked_tcb) {
  			SCTP_TCB_UNLOCK(locked_tcb);
  		}
  		return (NULL);
  	}
  	/*
  	 * validate the verification tag
  	 */
  	vtag_in = ntohl(sh->v_tag);
  
  	if (locked_tcb) {
  		SCTP_TCB_LOCK_ASSERT(locked_tcb);
  	}
  	if (ch->chunk_type == SCTP_INITIATION) {
  		SCTPDBG(SCTP_DEBUG_INPUT1, "Its an INIT of len:%d vtag:%x\n",
  			ntohs(ch->chunk_length), vtag_in);
  		if (vtag_in != 0) {
  			/* protocol error- silently discard... */
  			SCTP_STAT_INCR(sctps_badvtag);
  			if (locked_tcb) {
  				SCTP_TCB_UNLOCK(locked_tcb);
  			}
  			return (NULL);
  		}
  	} else if (ch->chunk_type != SCTP_COOKIE_ECHO) {
  		/*
  		 * If there is no stcb, skip the AUTH chunk and process
  		 * later after a stcb is found (to validate the lookup was
  		 * valid.
  		 */
  		if ((ch->chunk_type == SCTP_AUTHENTICATION) &&
  		    (stcb == NULL) &&
  		    (inp->auth_supported == 1)) {
  			/* save this chunk for later processing */
  			auth_skipped = 1;
  			auth_offset = *offset;
  			auth_len = ntohs(ch->chunk_length);
  
  			/* (temporarily) move past this chunk */
  			*offset += SCTP_SIZE32(auth_len);
  			if (*offset >= length) {
  				/* no more data left in the mbuf chain */
  				*offset = length;
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				return (NULL);
  			}
  			ch = (struct sctp_chunkhdr *)sctp_m_getptr(m, *offset,
  								   sizeof(struct sctp_chunkhdr), chunk_buf);
  		}
  		if (ch == NULL) {
  			/* Help */
  			*offset = length;
  			if (locked_tcb) {
  				SCTP_TCB_UNLOCK(locked_tcb);
  			}
  			return (NULL);
  		}
  		if (ch->chunk_type == SCTP_COOKIE_ECHO) {
  			goto process_control_chunks;
  		}
  		/*
  		 * first check if it's an ASCONF with an unknown src addr we
  		 * need to look inside to find the association
  		 */
  		if (ch->chunk_type == SCTP_ASCONF && stcb == NULL) {
  			struct sctp_chunkhdr *asconf_ch = ch;
  			uint32_t asconf_offset = 0, asconf_len = 0;
  
  			/* inp's refcount may be reduced */
  			SCTP_INP_INCR_REF(inp);
  
  			asconf_offset = *offset;
  			do {
  				asconf_len = ntohs(asconf_ch->chunk_length);
  				if (asconf_len < sizeof(struct sctp_asconf_paramhdr))
  					break;
  				stcb = sctp_findassociation_ep_asconf(m,
  				                                      *offset,
  				                                      dst,
  				                                      sh, &inp, netp, vrf_id);
  				if (stcb != NULL)
  					break;
  				asconf_offset += SCTP_SIZE32(asconf_len);
  				asconf_ch = (struct sctp_chunkhdr *)sctp_m_getptr(m, asconf_offset,
  										  sizeof(struct sctp_chunkhdr), chunk_buf);
  			} while (asconf_ch != NULL && asconf_ch->chunk_type == SCTP_ASCONF);
  			if (stcb == NULL) {
  				/*
  				 * reduce inp's refcount if not reduced in
  				 * sctp_findassociation_ep_asconf().
  				 */
  				SCTP_INP_DECR_REF(inp);
  			} else {
  				locked_tcb = stcb;
  			}
  
  			/* now go back and verify any auth chunk to be sure */
  			if (auth_skipped && (stcb != NULL)) {
  				struct sctp_auth_chunk *auth;
  
  				auth = (struct sctp_auth_chunk *)
  					sctp_m_getptr(m, auth_offset,
  						      auth_len, chunk_buf);
  				got_auth = 1;
  				auth_skipped = 0;
  				if ((auth == NULL) || sctp_handle_auth(stcb, auth, m,
  								       auth_offset)) {
  					/* auth HMAC failed so dump it */
  					*offset = length;
  					if (locked_tcb) {
  						SCTP_TCB_UNLOCK(locked_tcb);
  					}
  					return (NULL);
  				} else {
  					/* remaining chunks are HMAC checked */
  					stcb->asoc.authenticated = 1;
  				}
  			}
  		}
  		if (stcb == NULL) {
  			snprintf(msg, sizeof(msg), "OOTB, %s:%d at %s", __FILE__, __LINE__, __func__);
  			op_err = sctp_generate_cause(SCTP_BASE_SYSCTL(sctp_diag_info_code),
  			                             msg);
  			/* no association, so it's out of the blue... */
  			sctp_handle_ootb(m, iphlen, *offset, src, dst, sh, inp, op_err,
  #if defined(__FreeBSD__)
  			                 mflowtype, mflowid, inp->fibnum,
  #endif
  					 vrf_id, port);
  			*offset = length;
  			if (locked_tcb) {
  				SCTP_TCB_UNLOCK(locked_tcb);
  			}
  			return (NULL);
  		}
  		asoc = &stcb->asoc;
  		/* ABORT and SHUTDOWN can use either v_tag... */
  		if ((ch->chunk_type == SCTP_ABORT_ASSOCIATION) ||
  		    (ch->chunk_type == SCTP_SHUTDOWN_COMPLETE) ||
  		    (ch->chunk_type == SCTP_PACKET_DROPPED)) {
  			/* Take the T-bit always into account. */
  			if ((((ch->chunk_flags & SCTP_HAD_NO_TCB) == 0) &&
  			     (vtag_in == asoc->my_vtag)) ||
  			    (((ch->chunk_flags & SCTP_HAD_NO_TCB) == SCTP_HAD_NO_TCB) &&
  			     (vtag_in == asoc->peer_vtag))) {
  				/* this is valid */
  			} else {
  				/* drop this packet... */
  				SCTP_STAT_INCR(sctps_badvtag);
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				return (NULL);
  			}
  		} else if (ch->chunk_type == SCTP_SHUTDOWN_ACK) {
  			if (vtag_in != asoc->my_vtag) {
  				/*
  				 * this could be a stale SHUTDOWN-ACK or the
  				 * peer never got the SHUTDOWN-COMPLETE and
  				 * is still hung; we have started a new asoc
  				 * but it won't complete until the shutdown
  				 * is completed
  				 */
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				snprintf(msg, sizeof(msg), "OOTB, %s:%d at %s", __FILE__, __LINE__, __func__);
  				op_err = sctp_generate_cause(SCTP_BASE_SYSCTL(sctp_diag_info_code),
  				                             msg);
  				sctp_handle_ootb(m, iphlen, *offset, src, dst,
  				                 sh, inp, op_err,
  #if defined(__FreeBSD__)
  				                 mflowtype, mflowid, fibnum,
  #endif
  				                 vrf_id, port);
  				return (NULL);
  			}
  		} else {
  			/* for all other chunks, vtag must match */
  			if (vtag_in != asoc->my_vtag) {
  				/* invalid vtag... */
  				SCTPDBG(SCTP_DEBUG_INPUT3,
  					"invalid vtag: %xh, expect %xh\n",
  					vtag_in, asoc->my_vtag);
  				SCTP_STAT_INCR(sctps_badvtag);
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				*offset = length;
  				return (NULL);
  			}
  		}
  	}			/* end if !SCTP_COOKIE_ECHO */
  	/*
  	 * process all control chunks...
  	 */
  	if (((ch->chunk_type == SCTP_SELECTIVE_ACK) ||
  	     (ch->chunk_type == SCTP_NR_SELECTIVE_ACK) ||
  	     (ch->chunk_type == SCTP_HEARTBEAT_REQUEST)) &&
  	    (SCTP_GET_STATE(&stcb->asoc) == SCTP_STATE_COOKIE_ECHOED)) {
  		/* implied cookie-ack.. we must have lost the ack */
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
  			sctp_misc_ints(SCTP_THRESHOLD_CLEAR,
  				       stcb->asoc.overall_error_count,
  				       0,
  				       SCTP_FROM_SCTP_INPUT,
  				       __LINE__);
  		}
  		stcb->asoc.overall_error_count = 0;
  		sctp_handle_cookie_ack((struct sctp_cookie_ack_chunk *)ch, stcb,
  				       *netp);
  	}
  
   process_control_chunks:
  	while (IS_SCTP_CONTROL(ch)) {
  		/* validate chunk length */
  		chk_length = ntohs(ch->chunk_length);
  		SCTPDBG(SCTP_DEBUG_INPUT2, "sctp_process_control: processing a chunk type=%u, len=%u\n",
  			ch->chunk_type, chk_length);
  		SCTP_LTRACE_CHK(inp, stcb, ch->chunk_type, chk_length);
  		if (chk_length < sizeof(*ch) ||
  		    (*offset + (int)chk_length) > length) {
  			*offset = length;
  			if (locked_tcb) {
  				SCTP_TCB_UNLOCK(locked_tcb);
  			}
  			return (NULL);
  		}
  		SCTP_STAT_INCR_COUNTER64(sctps_incontrolchunks);
  		/*
  		 * INIT-ACK only gets the init ack "header" portion only
  		 * because we don't have to process the peer's COOKIE. All
  		 * others get a complete chunk.
  		 */
  		if ((ch->chunk_type == SCTP_INITIATION_ACK) ||
  		    (ch->chunk_type == SCTP_INITIATION)) {
  			/* get an init-ack chunk */
  			ch = (struct sctp_chunkhdr *)sctp_m_getptr(m, *offset,
  								   sizeof(struct sctp_init_ack_chunk), chunk_buf);
  			if (ch == NULL) {
  				*offset = length;
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				return (NULL);
  			}
  		} else {
  			/* For cookies and all other chunks. */
  			if (chk_length > sizeof(chunk_buf)) {
  				/*
  				 * use just the size of the chunk buffer
  				 * so the front part of our chunks fit in
  				 * contiguous space up to the chunk buffer
  				 * size (508 bytes).
  				 * For chunks that need to get more than that
  				 * they must use the sctp_m_getptr() function
  				 * or other means (e.g. know how to parse mbuf
  				 * chains). Cookies do this already.
  				 */
  				ch = (struct sctp_chunkhdr *)sctp_m_getptr(m, *offset,
  									   (sizeof(chunk_buf) - 4),
  									   chunk_buf);
  				if (ch == NULL) {
  					*offset = length;
  					if (locked_tcb) {
  						SCTP_TCB_UNLOCK(locked_tcb);
  					}
  					return (NULL);
  				}
  			} else {
  				/* We can fit it all */
  				ch = (struct sctp_chunkhdr *)sctp_m_getptr(m, *offset,
  								   chk_length, chunk_buf);
  				if (ch == NULL) {
  					SCTP_PRINTF("sctp_process_control: Can't get the all data....\n");
  					*offset = length;
  					if (locked_tcb) {
  						SCTP_TCB_UNLOCK(locked_tcb);
  					}
  					return (NULL);
  				}
  			}
  		}
  		num_chunks++;
  		/* Save off the last place we got a control from */
  		if (stcb != NULL) {
  			if (((netp != NULL) && (*netp != NULL)) || (ch->chunk_type == SCTP_ASCONF)) {
  				/*
  				 * allow last_control to be NULL if
  				 * ASCONF... ASCONF processing will find the
  				 * right net later
  				 */
  				if ((netp != NULL) && (*netp != NULL))
  					stcb->asoc.last_control_chunk_from = *netp;
  			}
  		}
  #ifdef SCTP_AUDITING_ENABLED
  		sctp_audit_log(0xB0, ch->chunk_type);
  #endif
  
  		/* check to see if this chunk required auth, but isn't */
  		if ((stcb != NULL) &&
  		    (stcb->asoc.auth_supported == 1) &&
  		    sctp_auth_is_required_chunk(ch->chunk_type, stcb->asoc.local_auth_chunks) &&
  		    !stcb->asoc.authenticated) {
  			/* "silently" ignore */
  			SCTP_STAT_INCR(sctps_recvauthmissing);
  			goto next_chunk;
  		}
  		switch (ch->chunk_type) {
  		case SCTP_INITIATION:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_INIT\n");
  			/* The INIT chunk must be the only chunk. */
  			if ((num_chunks > 1) ||
  			    (length - *offset > (int)SCTP_SIZE32(chk_length))) {
  				/* RFC 4960 requires that no ABORT is sent */
  				*offset = length;
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				return (NULL);
  			}
  			/* Honor our resource limit. */
  			if (chk_length > SCTP_LARGEST_INIT_ACCEPTED) {
  				op_err = sctp_generate_cause(SCTP_CAUSE_OUT_OF_RESC, "");
  				sctp_abort_association(inp, stcb, m, iphlen,
  						       src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  				                       mflowtype, mflowid,
  #endif
  				                       vrf_id, port);
  				*offset = length;
  				return (NULL);
  			}
  			sctp_handle_init(m, iphlen, *offset, src, dst, sh,
  			                 (struct sctp_init_chunk *)ch, inp,
  			                 stcb, *netp, &abort_no_unlock,
  #if defined(__FreeBSD__)
  			                 mflowtype, mflowid,
  #endif
  			                 vrf_id, port);
  			*offset = length;
  			if ((!abort_no_unlock) && (locked_tcb)) {
  				SCTP_TCB_UNLOCK(locked_tcb);
  			}
  			return (NULL);
  			break;
  		case SCTP_PAD_CHUNK:
  			break;
  		case SCTP_INITIATION_ACK:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_INIT-ACK\n");
  			if (inp->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) {
  				/* We are not interested anymore */
  				if ((stcb) && (stcb->asoc.total_output_queue_size)) {
  					;
  				} else {
  					if ((locked_tcb != NULL) && (locked_tcb != stcb)) {
  						/* Very unlikely */
  						SCTP_TCB_UNLOCK(locked_tcb);
  					}
  					*offset = length;
  					if (stcb) {
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  						so = SCTP_INP_SO(inp);
  						atomic_add_int(&stcb->asoc.refcnt, 1);
  						SCTP_TCB_UNLOCK(stcb);
  						SCTP_SOCKET_LOCK(so, 1);
  						SCTP_TCB_LOCK(stcb);
  						atomic_subtract_int(&stcb->asoc.refcnt, 1);
  #endif
  						(void)sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC,
  						                      SCTP_FROM_SCTP_INPUT + SCTP_LOC_29);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  						SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  					}
  					return (NULL);
  				}
  			}
  			/* The INIT-ACK chunk must be the only chunk. */
  			if ((num_chunks > 1) ||
  			    (length - *offset > (int)SCTP_SIZE32(chk_length))) {
  				*offset = length;
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				return (NULL);
  			}
  			if ((netp) && (*netp)) {
  				ret = sctp_handle_init_ack(m, iphlen, *offset,
  				                           src, dst, sh,
  				                           (struct sctp_init_ack_chunk *)ch,
  				                           stcb, *netp,
  				                           &abort_no_unlock,
  #if defined(__FreeBSD__)
  				                           mflowtype, mflowid,
  #endif
  				                           vrf_id);
  			} else {
  				ret = -1;
  			}
  			*offset = length;
  			if (abort_no_unlock) {
  				return (NULL);
  			}
  			/*
  			 * Special case, I must call the output routine to
  			 * get the cookie echoed
  			 */
  			if ((stcb != NULL) && (ret == 0)) {
  				sctp_chunk_output(stcb->sctp_ep, stcb, SCTP_OUTPUT_FROM_CONTROL_PROC, SCTP_SO_NOT_LOCKED);
  			}
  			if (locked_tcb) {
  				SCTP_TCB_UNLOCK(locked_tcb);
  			}
  			return (NULL);
  			break;
  		case SCTP_SELECTIVE_ACK:
  			{
  				struct sctp_sack_chunk *sack;
  				int abort_now = 0;
  				uint32_t a_rwnd, cum_ack;
  				uint16_t num_seg, num_dup;
  				uint8_t flags;
  				int offset_seg, offset_dup;
  
  				SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_SACK\n");
  				SCTP_STAT_INCR(sctps_recvsacks);
  				if (stcb == NULL) {
  					SCTPDBG(SCTP_DEBUG_INDATA1, "No stcb when processing SACK chunk\n");
  					break;
  				}
  				if (chk_length < sizeof(struct sctp_sack_chunk)) {
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Bad size on SACK chunk, too small\n");
  					break;
  				}
  				if (SCTP_GET_STATE(&stcb->asoc) == SCTP_STATE_SHUTDOWN_ACK_SENT) {
  					/*-
  					 * If we have sent a shutdown-ack, we will pay no
  					 * attention to a sack sent in to us since
  					 * we don't care anymore.
  					 */
  					break;
  				}
  				sack = (struct sctp_sack_chunk *)ch;
  				flags = ch->chunk_flags;
  				cum_ack = ntohl(sack->sack.cum_tsn_ack);
  				num_seg = ntohs(sack->sack.num_gap_ack_blks);
  				num_dup = ntohs(sack->sack.num_dup_tsns);
  				a_rwnd = (uint32_t) ntohl(sack->sack.a_rwnd);
  				if (sizeof(struct sctp_sack_chunk) +
  				    num_seg * sizeof(struct sctp_gap_ack_block) +
  				    num_dup * sizeof(uint32_t) != chk_length) {
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Bad size of SACK chunk\n");
  					break;
  				}
  				offset_seg = *offset + sizeof(struct sctp_sack_chunk);
  				offset_dup = offset_seg + num_seg * sizeof(struct sctp_gap_ack_block);
  				SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_SACK process cum_ack:%x num_seg:%d a_rwnd:%d\n",
  				        cum_ack, num_seg, a_rwnd);
  				stcb->asoc.seen_a_sack_this_pkt = 1;
  				if ((stcb->asoc.pr_sctp_cnt == 0) &&
  				    (num_seg == 0) &&
  				    SCTP_TSN_GE(cum_ack, stcb->asoc.last_acked_seq) &&
  				    (stcb->asoc.saw_sack_with_frags == 0) &&
  				    (stcb->asoc.saw_sack_with_nr_frags == 0) &&
  				    (!TAILQ_EMPTY(&stcb->asoc.sent_queue))
  					) {
  					/* We have a SIMPLE sack having no prior segments and
  					 * data on sent queue to be acked.. Use the faster
  					 * path sack processing. We also allow window update
  					 * sacks with no missing segments to go this way too.
  					 */
  					sctp_express_handle_sack(stcb, cum_ack, a_rwnd, &abort_now, ecne_seen);
  				} else {
  					if (netp && *netp)
  						sctp_handle_sack(m, offset_seg, offset_dup, stcb,
  								 num_seg, 0, num_dup, &abort_now, flags,
  								 cum_ack, a_rwnd, ecne_seen);
  				}
  				if (abort_now) {
  					/* ABORT signal from sack processing */
  					*offset = length;
  					return (NULL);
  				}
  				if (TAILQ_EMPTY(&stcb->asoc.send_queue) &&
  				    TAILQ_EMPTY(&stcb->asoc.sent_queue) &&
  				    (stcb->asoc.stream_queue_cnt == 0)) {
  					sctp_ulp_notify(SCTP_NOTIFY_SENDER_DRY, stcb,  0, NULL, SCTP_SO_NOT_LOCKED);
  				}
  			}
  			break;
  		/* EY - nr_sack:  If the received chunk is an nr_sack chunk */
  		case SCTP_NR_SELECTIVE_ACK:
  			{
  				struct sctp_nr_sack_chunk *nr_sack;
  				int abort_now = 0;
  				uint32_t a_rwnd, cum_ack;
  				uint16_t num_seg, num_nr_seg, num_dup;
  				uint8_t flags;
  				int offset_seg, offset_dup;
  
  				SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_NR_SACK\n");
  				SCTP_STAT_INCR(sctps_recvsacks);
  				if (stcb == NULL) {
  					SCTPDBG(SCTP_DEBUG_INDATA1, "No stcb when processing NR-SACK chunk\n");
  					break;
  				}
  				if (stcb->asoc.nrsack_supported == 0) {
  					goto unknown_chunk;
  				}
  				if (chk_length < sizeof(struct sctp_nr_sack_chunk)) {
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Bad size on NR-SACK chunk, too small\n");
  					break;
  				}
  				if (SCTP_GET_STATE(&stcb->asoc) == SCTP_STATE_SHUTDOWN_ACK_SENT) {
  					/*-
  					 * If we have sent a shutdown-ack, we will pay no
  					 * attention to a sack sent in to us since
  					 * we don't care anymore.
  					 */
  					break;
  				}
  				nr_sack = (struct sctp_nr_sack_chunk *)ch;
  				flags = ch->chunk_flags;
  				cum_ack = ntohl(nr_sack->nr_sack.cum_tsn_ack);
  				num_seg = ntohs(nr_sack->nr_sack.num_gap_ack_blks);
  				num_nr_seg = ntohs(nr_sack->nr_sack.num_nr_gap_ack_blks);
  				num_dup = ntohs(nr_sack->nr_sack.num_dup_tsns);
  				a_rwnd = (uint32_t) ntohl(nr_sack->nr_sack.a_rwnd);
  				if (sizeof(struct sctp_nr_sack_chunk) +
  				    (num_seg + num_nr_seg) * sizeof(struct sctp_gap_ack_block) +
  				    num_dup * sizeof(uint32_t) != chk_length) {
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Bad size of NR_SACK chunk\n");
  					break;
  				}
  				offset_seg = *offset + sizeof(struct sctp_nr_sack_chunk);
  				offset_dup = offset_seg + num_seg * sizeof(struct sctp_gap_ack_block);
  				SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_NR_SACK process cum_ack:%x num_seg:%d a_rwnd:%d\n",
  				        cum_ack, num_seg, a_rwnd);
  				stcb->asoc.seen_a_sack_this_pkt = 1;
  				if ((stcb->asoc.pr_sctp_cnt == 0) &&
  				    (num_seg == 0) && (num_nr_seg == 0) &&
  				    SCTP_TSN_GE(cum_ack, stcb->asoc.last_acked_seq) &&
  				    (stcb->asoc.saw_sack_with_frags == 0) &&
  				    (stcb->asoc.saw_sack_with_nr_frags == 0) &&
  				    (!TAILQ_EMPTY(&stcb->asoc.sent_queue))) {
  					/*
  					 * We have a SIMPLE sack having no
  					 * prior segments and data on sent
  					 * queue to be acked. Use the
  					 * faster path sack processing. We
  					 * also allow window update sacks
  					 * with no missing segments to go
  					 * this way too.
  					 */
  					sctp_express_handle_sack(stcb, cum_ack, a_rwnd,
  					                         &abort_now, ecne_seen);
  				} else {
  					if (netp && *netp)
  						sctp_handle_sack(m, offset_seg, offset_dup, stcb,
  						                 num_seg, num_nr_seg, num_dup, &abort_now, flags,
  						                 cum_ack, a_rwnd, ecne_seen);
  				}
  				if (abort_now) {
  					/* ABORT signal from sack processing */
  					*offset = length;
  					return (NULL);
  				}
  				if (TAILQ_EMPTY(&stcb->asoc.send_queue) &&
  				    TAILQ_EMPTY(&stcb->asoc.sent_queue) &&
  				    (stcb->asoc.stream_queue_cnt == 0)) {
  					sctp_ulp_notify(SCTP_NOTIFY_SENDER_DRY, stcb,  0, NULL, SCTP_SO_NOT_LOCKED);
  				}
  			}
  			break;
  
  		case SCTP_HEARTBEAT_REQUEST:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_HEARTBEAT\n");
  			if ((stcb) && netp && *netp) {
  				SCTP_STAT_INCR(sctps_recvheartbeat);
  				sctp_send_heartbeat_ack(stcb, m, *offset,
  							chk_length, *netp);
  
  				/* He's alive so give him credit */
  				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
  					sctp_misc_ints(SCTP_THRESHOLD_CLEAR,
  						       stcb->asoc.overall_error_count,
  						       0,
  						       SCTP_FROM_SCTP_INPUT,
  						       __LINE__);
  				}
  				stcb->asoc.overall_error_count = 0;
  			}
  			break;
  		case SCTP_HEARTBEAT_ACK:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_HEARTBEAT-ACK\n");
  			if ((stcb == NULL) || (chk_length != sizeof(struct sctp_heartbeat_chunk))) {
  				/* Its not ours */
  				*offset = length;
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				return (NULL);
  			}
  			/* He's alive so give him credit */
  			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
  				sctp_misc_ints(SCTP_THRESHOLD_CLEAR,
  					       stcb->asoc.overall_error_count,
  					       0,
  					       SCTP_FROM_SCTP_INPUT,
  					       __LINE__);
  			}
  			stcb->asoc.overall_error_count = 0;
  			SCTP_STAT_INCR(sctps_recvheartbeatack);
  			if (netp && *netp)
  				sctp_handle_heartbeat_ack((struct sctp_heartbeat_chunk *)ch,
  							  stcb, *netp);
  			break;
  		case SCTP_ABORT_ASSOCIATION:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_ABORT, stcb %p\n",
  				(void *)stcb);
  			if ((stcb) && netp && *netp)
  				sctp_handle_abort((struct sctp_abort_chunk *)ch,
  						  stcb, *netp);
  			*offset = length;
  			return (NULL);
  			break;
  		case SCTP_SHUTDOWN:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_SHUTDOWN, stcb %p\n",
  				(void *)stcb);
  			if ((stcb == NULL) || (chk_length != sizeof(struct sctp_shutdown_chunk))) {
  				*offset = length;
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				return (NULL);
  			}
  			if (netp && *netp) {
  				int abort_flag = 0;
  
  				sctp_handle_shutdown((struct sctp_shutdown_chunk *)ch,
  						     stcb, *netp, &abort_flag);
  				if (abort_flag) {
  					*offset = length;
  					return (NULL);
  				}
  			}
  			break;
  		case SCTP_SHUTDOWN_ACK:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_SHUTDOWN-ACK, stcb %p\n", (void *)stcb);
  			if ((stcb) && (netp) && (*netp))
  				sctp_handle_shutdown_ack((struct sctp_shutdown_ack_chunk *)ch, stcb, *netp);
  			*offset = length;
  			return (NULL);
  			break;
  
  		case SCTP_OPERATION_ERROR:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_OP-ERR\n");
  			if ((stcb) && netp && *netp && sctp_handle_error(ch, stcb, *netp) < 0) {
  				*offset = length;
  				return (NULL);
  			}
  			break;
  		case SCTP_COOKIE_ECHO:
  			SCTPDBG(SCTP_DEBUG_INPUT3,
  				"SCTP_COOKIE-ECHO, stcb %p\n", (void *)stcb);
  			if ((stcb) && (stcb->asoc.total_output_queue_size)) {
  				;
  			} else {
  				if (inp->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) {
  					/* We are not interested anymore */
  				abend:
  					if (stcb) {
  						SCTP_TCB_UNLOCK(stcb);
  					}
  					*offset = length;
  					return (NULL);
  				}
  			}
  			/*
  			 * First are we accepting? We do this again here
  			 * since it is possible that a previous endpoint WAS
  			 * listening responded to a INIT-ACK and then
  			 * closed. We opened and bound.. and are now no
  			 * longer listening.
  			 */
  
  			if ((stcb == NULL) && (inp->sctp_socket->so_qlen >= inp->sctp_socket->so_qlimit)) {
  				if ((inp->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) &&
  				    (SCTP_BASE_SYSCTL(sctp_abort_if_one_2_one_hits_limit))) {
  					op_err = sctp_generate_cause(SCTP_CAUSE_OUT_OF_RESC, "");
  					sctp_abort_association(inp, stcb, m, iphlen,
  					                       src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  					                       mflowtype, mflowid,
  #endif
  					                       vrf_id, port);
  				}
  				*offset = length;
  				return (NULL);
  			} else {
  				struct mbuf *ret_buf;
  				struct sctp_inpcb *linp;
  				if (stcb) {
  					linp = NULL;
  				} else {
  					linp = inp;
  				}
  
  				if (linp) {
  					SCTP_ASOC_CREATE_LOCK(linp);
  					if ((inp->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) ||
  					    (inp->sctp_flags & SCTP_PCB_FLAGS_SOCKET_ALLGONE)) {
  						SCTP_ASOC_CREATE_UNLOCK(linp);
  						goto abend;
  					}
  				}
  
  				if (netp) {
  					ret_buf =
  						sctp_handle_cookie_echo(m, iphlen,
  						                        *offset,
  						                        src, dst,
  						                        sh,
  						                        (struct sctp_cookie_echo_chunk *)ch,
  						                        &inp, &stcb, netp,
  						                        auth_skipped,
  						                        auth_offset,
  						                        auth_len,
  						                        &locked_tcb,
  #if defined(__FreeBSD__)
  						                        mflowtype,
  						                        mflowid,
  #endif
  						                        vrf_id,
  						                        port);
  				} else {
  					ret_buf = NULL;
  				}
  				if (linp) {
  					SCTP_ASOC_CREATE_UNLOCK(linp);
  				}
  				if (ret_buf == NULL) {
  					if (locked_tcb) {
  						SCTP_TCB_UNLOCK(locked_tcb);
  					}
  					SCTPDBG(SCTP_DEBUG_INPUT3,
  						"GAK, null buffer\n");
  					*offset = length;
  					return (NULL);
  				}
  				/* if AUTH skipped, see if it verified... */
  				if (auth_skipped) {
  					got_auth = 1;
  					auth_skipped = 0;
  				}
  				if (!TAILQ_EMPTY(&stcb->asoc.sent_queue)) {
  					/*
  					 * Restart the timer if we have
  					 * pending data
  					 */
  					struct sctp_tmit_chunk *chk;
  
  					chk = TAILQ_FIRST(&stcb->asoc.sent_queue);
  					sctp_timer_start(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep, stcb, chk->whoTo);
  				}
  			}
  			break;
  		case SCTP_COOKIE_ACK:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_COOKIE-ACK, stcb %p\n", (void *)stcb);
  			if ((stcb == NULL) || chk_length != sizeof(struct sctp_cookie_ack_chunk)) {
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				return (NULL);
  			}
  			if (inp->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) {
  				/* We are not interested anymore */
  				if ((stcb) && (stcb->asoc.total_output_queue_size)) {
  					;
  				} else if (stcb) {
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  					so = SCTP_INP_SO(inp);
  					atomic_add_int(&stcb->asoc.refcnt, 1);
  					SCTP_TCB_UNLOCK(stcb);
  					SCTP_SOCKET_LOCK(so, 1);
  					SCTP_TCB_LOCK(stcb);
  					atomic_subtract_int(&stcb->asoc.refcnt, 1);
  #endif
  					(void)sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC,
  					                      SCTP_FROM_SCTP_INPUT + SCTP_LOC_30);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  					SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  					*offset = length;
  					return (NULL);
  				}
  			}
  			/* He's alive so give him credit */
  			if ((stcb) && netp && *netp) {
  				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
  					sctp_misc_ints(SCTP_THRESHOLD_CLEAR,
  						       stcb->asoc.overall_error_count,
  						       0,
  						       SCTP_FROM_SCTP_INPUT,
  						       __LINE__);
  				}
  				stcb->asoc.overall_error_count = 0;
  				sctp_handle_cookie_ack((struct sctp_cookie_ack_chunk *)ch,stcb, *netp);
  			}
  			break;
  		case SCTP_ECN_ECHO:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_ECN-ECHO\n");
  			/* He's alive so give him credit */
  			if ((stcb == NULL) || (chk_length != sizeof(struct sctp_ecne_chunk))) {
  				/* Its not ours */
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				*offset = length;
  				return (NULL);
  			}
  			if (stcb) {
  				if (stcb->asoc.ecn_supported == 0) {
  					goto unknown_chunk;
  				}
  				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
  					sctp_misc_ints(SCTP_THRESHOLD_CLEAR,
  						       stcb->asoc.overall_error_count,
  						       0,
  						       SCTP_FROM_SCTP_INPUT,
  						       __LINE__);
  				}
  				stcb->asoc.overall_error_count = 0;
  				sctp_handle_ecn_echo((struct sctp_ecne_chunk *)ch,
  						     stcb);
  				ecne_seen = 1;
  			}
  			break;
  		case SCTP_ECN_CWR:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_ECN-CWR\n");
  			/* He's alive so give him credit */
  			if ((stcb == NULL) || (chk_length != sizeof(struct sctp_cwr_chunk))) {
  				/* Its not ours */
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				*offset = length;
  				return (NULL);
  			}
  			if (stcb) {
  				if (stcb->asoc.ecn_supported == 0) {
  					goto unknown_chunk;
  				}
  				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
  					sctp_misc_ints(SCTP_THRESHOLD_CLEAR,
  						       stcb->asoc.overall_error_count,
  						       0,
  						       SCTP_FROM_SCTP_INPUT,
  						       __LINE__);
  				}
  				stcb->asoc.overall_error_count = 0;
  				sctp_handle_ecn_cwr((struct sctp_cwr_chunk *)ch, stcb, *netp);
  			}
  			break;
  		case SCTP_SHUTDOWN_COMPLETE:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_SHUTDOWN-COMPLETE, stcb %p\n", (void *)stcb);
  			/* must be first and only chunk */
  			if ((num_chunks > 1) ||
  			    (length - *offset > (int)SCTP_SIZE32(chk_length))) {
  				*offset = length;
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				return (NULL);
  			}
  			if ((stcb) && netp && *netp) {
  				sctp_handle_shutdown_complete((struct sctp_shutdown_complete_chunk *)ch,
  							      stcb, *netp);
  			}
  			*offset = length;
  			return (NULL);
  			break;
  		case SCTP_ASCONF:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_ASCONF\n");
  			/* He's alive so give him credit */
  			if (stcb) {
  				if (stcb->asoc.asconf_supported == 0) {
  					goto unknown_chunk;
  				}
  				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
  					sctp_misc_ints(SCTP_THRESHOLD_CLEAR,
  						       stcb->asoc.overall_error_count,
  						       0,
  						       SCTP_FROM_SCTP_INPUT,
  						       __LINE__);
  				}
  				stcb->asoc.overall_error_count = 0;
  				sctp_handle_asconf(m, *offset, src,
  						   (struct sctp_asconf_chunk *)ch, stcb, asconf_cnt == 0);
  				asconf_cnt++;
  			}
  			break;
  		case SCTP_ASCONF_ACK:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_ASCONF-ACK\n");
  			if (chk_length < sizeof(struct sctp_asconf_ack_chunk)) {
  				/* Its not ours */
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				*offset = length;
  				return (NULL);
  			}
  			if ((stcb) && netp && *netp) {
  				if (stcb->asoc.asconf_supported == 0) {
  					goto unknown_chunk;
  				}
  				/* He's alive so give him credit */
  				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
  					sctp_misc_ints(SCTP_THRESHOLD_CLEAR,
  						       stcb->asoc.overall_error_count,
  						       0,
  						       SCTP_FROM_SCTP_INPUT,
  						       __LINE__);
  				}
  				stcb->asoc.overall_error_count = 0;
  				sctp_handle_asconf_ack(m, *offset,
  						       (struct sctp_asconf_ack_chunk *)ch, stcb, *netp, &abort_no_unlock);
  				if (abort_no_unlock)
  					return (NULL);
  			}
  			break;
  		case SCTP_FORWARD_CUM_TSN:
  		case SCTP_IFORWARD_CUM_TSN:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_FWD-TSN\n");
  			if (chk_length < sizeof(struct sctp_forward_tsn_chunk)) {
  				/* Its not ours */
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				*offset = length;
  				return (NULL);
  			}
  
  			/* He's alive so give him credit */
  			if (stcb) {
  				int abort_flag = 0;
  
  				if (stcb->asoc.prsctp_supported == 0) {
  					goto unknown_chunk;
  				}
  				stcb->asoc.overall_error_count = 0;
  				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
  					sctp_misc_ints(SCTP_THRESHOLD_CLEAR,
  						       stcb->asoc.overall_error_count,
  						       0,
  						       SCTP_FROM_SCTP_INPUT,
  						       __LINE__);
  				}
  				*fwd_tsn_seen = 1;
  				if (inp->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) {
  					/* We are not interested anymore */
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  					so = SCTP_INP_SO(inp);
  					atomic_add_int(&stcb->asoc.refcnt, 1);
  					SCTP_TCB_UNLOCK(stcb);
  					SCTP_SOCKET_LOCK(so, 1);
  					SCTP_TCB_LOCK(stcb);
  					atomic_subtract_int(&stcb->asoc.refcnt, 1);
  #endif
  					(void)sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC,
  					                      SCTP_FROM_SCTP_INPUT + SCTP_LOC_31);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  					SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  					*offset = length;
  					return (NULL);
  				}
  				sctp_handle_forward_tsn(stcb,
  							(struct sctp_forward_tsn_chunk *)ch, &abort_flag, m, *offset);
  				if (abort_flag) {
  					*offset = length;
  					return (NULL);
  				} else {
  					if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
  						sctp_misc_ints(SCTP_THRESHOLD_CLEAR,
  							       stcb->asoc.overall_error_count,
  							       0,
  							       SCTP_FROM_SCTP_INPUT,
  							       __LINE__);
  					}
  					stcb->asoc.overall_error_count = 0;
  				}
  
  			}
  			break;
  		case SCTP_STREAM_RESET:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_STREAM_RESET\n");
  			if (((stcb == NULL) || (ch == NULL) || (chk_length < sizeof(struct sctp_stream_reset_tsn_req)))) {
  				/* Its not ours */
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				*offset = length;
  				return (NULL);
  			}
  			if (stcb->asoc.reconfig_supported == 0) {
  				goto unknown_chunk;
  			}
  			if (sctp_handle_stream_reset(stcb, m, *offset, ch)) {
  				/* stop processing */
  				*offset = length;
  				return (NULL);
  			}
  			break;
  		case SCTP_PACKET_DROPPED:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_PACKET_DROPPED\n");
  			/* re-get it all please */
  			if (chk_length < sizeof(struct sctp_pktdrop_chunk)) {
  				/* Its not ours */
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				*offset = length;
  				return (NULL);
  			}
  
  
  			if (ch && (stcb) && netp && (*netp)) {
  				if (stcb->asoc.pktdrop_supported == 0) {
  					goto unknown_chunk;
  				}
  				sctp_handle_packet_dropped((struct sctp_pktdrop_chunk *)ch,
  							   stcb, *netp,
  							   min(chk_length, (sizeof(chunk_buf) - 4)));
  
  			}
  
  			break;
  		case SCTP_AUTHENTICATION:
  			SCTPDBG(SCTP_DEBUG_INPUT3, "SCTP_AUTHENTICATION\n");
  			if (stcb == NULL) {
  				/* save the first AUTH for later processing */
  				if (auth_skipped == 0) {
  					auth_offset = *offset;
  					auth_len = chk_length;
  					auth_skipped = 1;
  				}
  				/* skip this chunk (temporarily) */
  				goto next_chunk;
  			}
  			if (stcb->asoc.auth_supported == 0) {
  				goto unknown_chunk;
  			}
  			if ((chk_length < (sizeof(struct sctp_auth_chunk))) ||
  			    (chk_length > (sizeof(struct sctp_auth_chunk) +
  					   SCTP_AUTH_DIGEST_LEN_MAX))) {
  				/* Its not ours */
  				if (locked_tcb) {
  					SCTP_TCB_UNLOCK(locked_tcb);
  				}
  				*offset = length;
  				return (NULL);
  			}
  			if (got_auth == 1) {
  				/* skip this chunk... it's already auth'd */
  				goto next_chunk;
  			}
  			got_auth = 1;
  			if ((ch == NULL) || sctp_handle_auth(stcb, (struct sctp_auth_chunk *)ch,
  							     m, *offset)) {
  				/* auth HMAC failed so dump the packet */
  				*offset = length;
  				return (stcb);
  			} else {
  				/* remaining chunks are HMAC checked */
  				stcb->asoc.authenticated = 1;
  			}
  			break;
  
  		default:
  		unknown_chunk:
  			/* it's an unknown chunk! */
  			if ((ch->chunk_type & 0x40) && (stcb != NULL)) {
  				struct sctp_gen_error_cause *cause;
  				int len;
  
  				op_err = sctp_get_mbuf_for_msg(sizeof(struct sctp_gen_error_cause),
  				                               0, M_NOWAIT, 1, MT_DATA);
  				if (op_err != NULL) {
  					len = min(SCTP_SIZE32(chk_length), (uint32_t)(length - *offset));
  					cause = mtod(op_err, struct sctp_gen_error_cause *);
  					cause->code =  htons(SCTP_CAUSE_UNRECOG_CHUNK);
  					cause->length = htons((uint16_t)(len + sizeof(struct sctp_gen_error_cause)));
  					SCTP_BUF_LEN(op_err) = sizeof(struct sctp_gen_error_cause);
  					SCTP_BUF_NEXT(op_err) = SCTP_M_COPYM(m, *offset, len, M_NOWAIT);
  					if (SCTP_BUF_NEXT(op_err) != NULL) {
  #ifdef SCTP_MBUF_LOGGING
  						if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MBUF_LOGGING_ENABLE) {
  							sctp_log_mbc(SCTP_BUF_NEXT(op_err), SCTP_MBUF_ICOPY);
  						}
  #endif
  						sctp_queue_op_err(stcb, op_err);
  					} else {
  						sctp_m_freem(op_err);
  					}
  				}
  			}
  			if ((ch->chunk_type & 0x80) == 0) {
  				/* discard this packet */
  				*offset = length;
  				return (stcb);
  			}	/* else skip this bad chunk and continue... */
  			break;
  		}		/* switch (ch->chunk_type) */
  
  
  	next_chunk:
  		/* get the next chunk */
  		*offset += SCTP_SIZE32(chk_length);
  		if (*offset >= length) {
  			/* no more data left in the mbuf chain */
  			break;
  		}
  		ch = (struct sctp_chunkhdr *)sctp_m_getptr(m, *offset,
  							   sizeof(struct sctp_chunkhdr), chunk_buf);
  		if (ch == NULL) {
  			if (locked_tcb) {
  				SCTP_TCB_UNLOCK(locked_tcb);
  			}
  			*offset = length;
  			return (NULL);
  		}
  	}			/* while */
  
  	if (asconf_cnt > 0 && stcb != NULL) {
  		sctp_send_asconf_ack(stcb);
  	}
  	return (stcb);
  }
  
  
  /*
   * common input chunk processing (v4 and v6)
   */
  void
  sctp_common_input_processing(struct mbuf **mm, int iphlen, int offset, int length,
                               struct sockaddr *src, struct sockaddr *dst,
                               struct sctphdr *sh, struct sctp_chunkhdr *ch,
  #if !defined(SCTP_WITH_NO_CSUM)
                               uint8_t compute_crc,
  #endif
                               uint8_t ecn_bits,
  #if defined(__FreeBSD__)
                               uint8_t mflowtype, uint32_t mflowid, uint16_t fibnum,
  #endif
                               uint32_t vrf_id, uint16_t port)
  {
  	uint32_t high_tsn;
  	int fwd_tsn_seen = 0, data_processed = 0;
  	struct mbuf *m = *mm, *op_err;
  	char msg[SCTP_DIAG_INFO_LEN];
  	int un_sent;
  	int cnt_ctrl_ready = 0;
  	struct sctp_inpcb *inp = NULL, *inp_decr = NULL;
  	struct sctp_tcb *stcb = NULL;
  	struct sctp_nets *net = NULL;
  
  	SCTP_STAT_INCR(sctps_recvdatagrams);
  #ifdef SCTP_AUDITING_ENABLED
  	sctp_audit_log(0xE0, 1);
  	sctp_auditing(0, inp, stcb, net);
  #endif
  #if !defined(SCTP_WITH_NO_CSUM)
  	if (compute_crc != 0) {
  		uint32_t check, calc_check;
  
  		check = sh->checksum;
  		sh->checksum = 0;
  		calc_check = sctp_calculate_cksum(m, iphlen);
  		sh->checksum = check;
  		if (calc_check != check) {
  			SCTPDBG(SCTP_DEBUG_INPUT1, "Bad CSUM on SCTP packet calc_check:%x check:%x  m:%p mlen:%d iphlen:%d\n",
  			        calc_check, check, (void *)m, length, iphlen);
  			stcb = sctp_findassociation_addr(m, offset, src, dst,
  			                                 sh, ch, &inp, &net, vrf_id);
  #if defined(INET) || defined(INET6)
  			if ((ch->chunk_type != SCTP_INITIATION) &&
  			    (net != NULL) && (net->port != port)) {
  				if (net->port == 0) {
  					/* UDP encapsulation turned on. */
  					net->mtu -= sizeof(struct udphdr);
  					if (stcb->asoc.smallest_mtu > net->mtu) {
  						sctp_pathmtu_adjustment(stcb, net->mtu);
  					}
  				} else if (port == 0) {
  					/* UDP encapsulation turned off. */
  					net->mtu += sizeof(struct udphdr);
  					/* XXX Update smallest_mtu */
  				}
  				net->port = port;
  			}
  #endif
  #if defined(__FreeBSD__)
  			if (net != NULL) {
  				net->flowtype = mflowtype;
  				net->flowid = mflowid;
  			}
  #endif
  			if ((inp != NULL) && (stcb != NULL)) {
  				sctp_send_packet_dropped(stcb, net, m, length, iphlen, 1);
  				sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_INPUT_ERROR, SCTP_SO_NOT_LOCKED);
  			} else if ((inp != NULL) && (stcb == NULL)) {
  				inp_decr = inp;
  			}
  			SCTP_STAT_INCR(sctps_badsum);
  			SCTP_STAT_INCR_COUNTER32(sctps_checksumerrors);
  			goto out;
  		}
  	}
  #endif
  	/* Destination port of 0 is illegal, based on RFC4960. */
  	if (sh->dest_port == 0) {
  		SCTP_STAT_INCR(sctps_hdrops);
  		goto out;
  	}
  	stcb = sctp_findassociation_addr(m, offset, src, dst,
  	                                 sh, ch, &inp, &net, vrf_id);
  #if defined(INET) || defined(INET6)
  	if ((ch->chunk_type != SCTP_INITIATION) &&
  	    (net != NULL) && (net->port != port)) {
  		if (net->port == 0) {
  			/* UDP encapsulation turned on. */
  			net->mtu -= sizeof(struct udphdr);
  			if (stcb->asoc.smallest_mtu > net->mtu) {
  				sctp_pathmtu_adjustment(stcb, net->mtu);
  			}
  		} else if (port == 0) {
  			/* UDP encapsulation turned off. */
  			net->mtu += sizeof(struct udphdr);
  			/* XXX Update smallest_mtu */
  		}
  		net->port = port;
  	}
  #endif
  #if defined(__FreeBSD__)
  	if (net != NULL) {
  		net->flowtype = mflowtype;
  		net->flowid = mflowid;
  	}
  #endif
  	if (inp == NULL) {
  		SCTP_STAT_INCR(sctps_noport);
  #if defined(__FreeBSD__) && (((__FreeBSD_version < 900000) && (__FreeBSD_version >= 804000)) || (__FreeBSD_version > 900000))
  		if (badport_bandlim(BANDLIM_SCTP_OOTB) < 0) {
  			goto out;
  		}
  #endif
  		if (ch->chunk_type == SCTP_SHUTDOWN_ACK) {
  			sctp_send_shutdown_complete2(src, dst, sh,
  #if defined(__FreeBSD__)
  			                             mflowtype, mflowid, fibnum,
  #endif
  			                             vrf_id, port);
  			goto out;
  		}
  		if (ch->chunk_type == SCTP_SHUTDOWN_COMPLETE) {
  			goto out;
  		}
  		if (ch->chunk_type != SCTP_ABORT_ASSOCIATION) {
  			if ((SCTP_BASE_SYSCTL(sctp_blackhole) == 0) ||
  			    ((SCTP_BASE_SYSCTL(sctp_blackhole) == 1) &&
  			     (ch->chunk_type != SCTP_INIT))) {
  				op_err = sctp_generate_cause(SCTP_BASE_SYSCTL(sctp_diag_info_code),
  				                             "Out of the blue");
  				sctp_send_abort(m, iphlen, src, dst,
  				                sh, 0, op_err,
  #if defined(__FreeBSD__)
  				                mflowtype, mflowid, fibnum,
  #endif
  				                vrf_id, port);
  			}
  		}
  		goto out;
  	} else if (stcb == NULL) {
  		inp_decr = inp;
  	}
  #ifdef IPSEC
  	/*-
  	 * I very much doubt any of the IPSEC stuff will work but I have no
  	 * idea, so I will leave it in place.
  	 */
  	if (inp != NULL) {
  		switch (dst->sa_family) {
  #ifdef INET
  		case AF_INET:
  			if (ipsec4_in_reject(m, &inp->ip_inp.inp)) {
  				SCTP_STAT_INCR(sctps_hdrops);
  				goto out;
  			}
  			break;
  #endif
  #ifdef INET6
  		case AF_INET6:
  			if (ipsec6_in_reject(m, &inp->ip_inp.inp)) {
  				SCTP_STAT_INCR(sctps_hdrops);
  				goto out;
  			}
  			break;
  #endif
  		default:
  			break;
  		}
  	}
  #endif
  	SCTPDBG(SCTP_DEBUG_INPUT1, "Ok, Common input processing called, m:%p iphlen:%d offset:%d length:%d stcb:%p\n",
  		(void *)m, iphlen, offset, length, (void *)stcb);
  	if (stcb) {
  		/* always clear this before beginning a packet */
  		stcb->asoc.authenticated = 0;
  		stcb->asoc.seen_a_sack_this_pkt = 0;
  		SCTPDBG(SCTP_DEBUG_INPUT1, "stcb:%p state:%x\n",
  			(void *)stcb, stcb->asoc.state);
  
  		if ((stcb->asoc.state & SCTP_STATE_WAS_ABORTED) ||
  		    (stcb->asoc.state & SCTP_STATE_ABOUT_TO_BE_FREED)) {
  			/*-
  			 * If we hit here, we had a ref count
  			 * up when the assoc was aborted and the
  			 * timer is clearing out the assoc, we should
  			 * NOT respond to any packet.. its OOTB.
  			 */
  			SCTP_TCB_UNLOCK(stcb);
  			stcb = NULL;
  			snprintf(msg, sizeof(msg), "OOTB, %s:%d at %s", __FILE__, __LINE__, __func__);
  			op_err = sctp_generate_cause(SCTP_BASE_SYSCTL(sctp_diag_info_code),
  			                             msg);
  			sctp_handle_ootb(m, iphlen, offset, src, dst, sh, inp, op_err,
  #if defined(__FreeBSD__)
  			                 mflowtype, mflowid, inp->fibnum,
  #endif
  			                 vrf_id, port);
  			goto out;
  		}
  
  	}
  	if (IS_SCTP_CONTROL(ch)) {
  		/* process the control portion of the SCTP packet */
  		/* sa_ignore NO_NULL_CHK */
  		stcb = sctp_process_control(m, iphlen, &offset, length,
  		                            src, dst, sh, ch,
  		                            inp, stcb, &net, &fwd_tsn_seen,
  #if defined(__FreeBSD__)
  		                            mflowtype, mflowid, fibnum,
  #endif
  		                            vrf_id, port);
  		if (stcb) {
  			/* This covers us if the cookie-echo was there
  			 * and it changes our INP.
  			 */
  			inp = stcb->sctp_ep;
  #if defined(INET) || defined(INET6)
  			if ((ch->chunk_type != SCTP_INITIATION) &&
  			    (net != NULL) && (net->port != port)) {
  				if (net->port == 0) {
  					/* UDP encapsulation turned on. */
  					net->mtu -= sizeof(struct udphdr);
  					if (stcb->asoc.smallest_mtu > net->mtu) {
  						sctp_pathmtu_adjustment(stcb, net->mtu);
  					}
  				} else if (port == 0) {
  					/* UDP encapsulation turned off. */
  					net->mtu += sizeof(struct udphdr);
  					/* XXX Update smallest_mtu */
  				}
  				net->port = port;
  			}
  #endif
  		}
  	} else {
  		/*
  		 * no control chunks, so pre-process DATA chunks (these
  		 * checks are taken care of by control processing)
  		 */
  
  		/*
  		 * if DATA only packet, and auth is required, then punt...
  		 * can't have authenticated without any AUTH (control)
  		 * chunks
  		 */
  		if ((stcb != NULL) &&
  		    (stcb->asoc.auth_supported == 1) &&
  		    sctp_auth_is_required_chunk(SCTP_DATA, stcb->asoc.local_auth_chunks)) {
  			/* "silently" ignore */
  			SCTP_STAT_INCR(sctps_recvauthmissing);
  			goto out;
  		}
  		if (stcb == NULL) {
  			/* out of the blue DATA chunk */
  			snprintf(msg, sizeof(msg), "OOTB, %s:%d at %s", __FILE__, __LINE__, __func__);
  			op_err = sctp_generate_cause(SCTP_BASE_SYSCTL(sctp_diag_info_code),
  			                             msg);
  			sctp_handle_ootb(m, iphlen, offset, src, dst, sh, inp, op_err,
  #if defined(__FreeBSD__)
  			                 mflowtype, mflowid, fibnum,
  #endif
  					 vrf_id, port);
  			goto out;
  		}
  		if (stcb->asoc.my_vtag != ntohl(sh->v_tag)) {
  			/* v_tag mismatch! */
  			SCTP_STAT_INCR(sctps_badvtag);
  			goto out;
  		}
  	}
  
  	if (stcb == NULL) {
  		/*
  		 * no valid TCB for this packet, or we found it's a bad
  		 * packet while processing control, or we're done with this
  		 * packet (done or skip rest of data), so we drop it...
  		 */
  		goto out;
  	}
  
  	/*
  	 * DATA chunk processing
  	 */
  	/* plow through the data chunks while length > offset */
  
  	/*
  	 * Rest should be DATA only.  Check authentication state if AUTH for
  	 * DATA is required.
  	 */
  	if ((length > offset) &&
  	    (stcb != NULL) &&
  	    (stcb->asoc.auth_supported == 1) &&
  	    sctp_auth_is_required_chunk(SCTP_DATA, stcb->asoc.local_auth_chunks) &&
  	    !stcb->asoc.authenticated) {
  		/* "silently" ignore */
  		SCTP_STAT_INCR(sctps_recvauthmissing);
  		SCTPDBG(SCTP_DEBUG_AUTH1,
  			"Data chunk requires AUTH, skipped\n");
  		goto trigger_send;
  	}
  	if (length > offset) {
  		int retval;
  
  		/*
  		 * First check to make sure our state is correct. We would
  		 * not get here unless we really did have a tag, so we don't
  		 * abort if this happens, just dump the chunk silently.
  		 */
  		switch (SCTP_GET_STATE(&stcb->asoc)) {
  		case SCTP_STATE_COOKIE_ECHOED:
  			/*
  			 * we consider data with valid tags in this state
  			 * shows us the cookie-ack was lost. Imply it was
  			 * there.
  			 */
  			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
  				sctp_misc_ints(SCTP_THRESHOLD_CLEAR,
  					       stcb->asoc.overall_error_count,
  					       0,
  					       SCTP_FROM_SCTP_INPUT,
  					       __LINE__);
  			}
  			stcb->asoc.overall_error_count = 0;
  			sctp_handle_cookie_ack((struct sctp_cookie_ack_chunk *)ch, stcb, net);
  			break;
  		case SCTP_STATE_COOKIE_WAIT:
  			/*
  			 * We consider OOTB any data sent during asoc setup.
  			 */
  			snprintf(msg, sizeof(msg), "OOTB, %s:%d at %s", __FILE__, __LINE__, __func__);
  			op_err = sctp_generate_cause(SCTP_BASE_SYSCTL(sctp_diag_info_code),
  			                             msg);
  			sctp_handle_ootb(m, iphlen, offset, src, dst, sh, inp, op_err,
  #if defined(__FreeBSD__)
  			                 mflowtype, mflowid, inp->fibnum,
  #endif
  					 vrf_id, port);
  			goto out;
  			/*sa_ignore NOTREACHED*/
  			break;
  		case SCTP_STATE_EMPTY:	/* should not happen */
  		case SCTP_STATE_INUSE:	/* should not happen */
  		case SCTP_STATE_SHUTDOWN_RECEIVED:	/* This is a peer error */
  		case SCTP_STATE_SHUTDOWN_ACK_SENT:
  		default:
  			goto out;
  			/*sa_ignore NOTREACHED*/
  			break;
  		case SCTP_STATE_OPEN:
  		case SCTP_STATE_SHUTDOWN_SENT:
  			break;
  		}
  		/* plow through the data chunks while length > offset */
  		retval = sctp_process_data(mm, iphlen, &offset, length,
  		                           inp, stcb, net, &high_tsn);
  		if (retval == 2) {
  			/*
  			 * The association aborted, NO UNLOCK needed since
  			 * the association is destroyed.
  			 */
  			stcb = NULL;
  			goto out;
  		}
  		data_processed = 1;
  		/*
  		 * Anything important needs to have been m_copy'ed in
  		 * process_data
  		 */
  	}
  
  	/* take care of ecn */
  	if ((data_processed == 1) &&
  	    (stcb->asoc.ecn_supported == 1) &&
  	    ((ecn_bits & SCTP_CE_BITS) == SCTP_CE_BITS)) {
  		/* Yep, we need to add a ECNE */
  		sctp_send_ecn_echo(stcb, net, high_tsn);
  	}
  
  	if ((data_processed == 0) && (fwd_tsn_seen)) {
  		int was_a_gap;
  		uint32_t highest_tsn;
  
  		if (SCTP_TSN_GT(stcb->asoc.highest_tsn_inside_nr_map, stcb->asoc.highest_tsn_inside_map)) {
  			highest_tsn = stcb->asoc.highest_tsn_inside_nr_map;
  		} else {
  			highest_tsn = stcb->asoc.highest_tsn_inside_map;
  		}
  		was_a_gap = SCTP_TSN_GT(highest_tsn, stcb->asoc.cumulative_tsn);
  		stcb->asoc.send_sack = 1;
  		sctp_sack_check(stcb, was_a_gap);
  	} else if (fwd_tsn_seen) {
  		stcb->asoc.send_sack = 1;
  	}
  	/* trigger send of any chunks in queue... */
  trigger_send:
  #ifdef SCTP_AUDITING_ENABLED
  	sctp_audit_log(0xE0, 2);
  	sctp_auditing(1, inp, stcb, net);
  #endif
  	SCTPDBG(SCTP_DEBUG_INPUT1,
  		"Check for chunk output prw:%d tqe:%d tf=%d\n",
  		stcb->asoc.peers_rwnd,
  		TAILQ_EMPTY(&stcb->asoc.control_send_queue),
  		stcb->asoc.total_flight);
  	un_sent = (stcb->asoc.total_output_queue_size - stcb->asoc.total_flight);
  	if (!TAILQ_EMPTY(&stcb->asoc.control_send_queue)) {
  		cnt_ctrl_ready = stcb->asoc.ctrl_queue_cnt - stcb->asoc.ecn_echo_cnt_onq;
  	}
  	if (!TAILQ_EMPTY(&stcb->asoc.asconf_send_queue) ||
  	    cnt_ctrl_ready ||
  	    stcb->asoc.trigger_reset ||
  	    ((un_sent) &&
  	     (stcb->asoc.peers_rwnd > 0 ||
  	      (stcb->asoc.peers_rwnd <= 0 && stcb->asoc.total_flight == 0)))) {
  		SCTPDBG(SCTP_DEBUG_INPUT3, "Calling chunk OUTPUT\n");
  		sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_CONTROL_PROC, SCTP_SO_NOT_LOCKED);
  		SCTPDBG(SCTP_DEBUG_INPUT3, "chunk OUTPUT returns\n");
  	}
  #ifdef SCTP_AUDITING_ENABLED
  	sctp_audit_log(0xE0, 3);
  	sctp_auditing(2, inp, stcb, net);
  #endif
   out:
  	if (stcb != NULL) {
  		SCTP_TCB_UNLOCK(stcb);
  	}
  	if (inp_decr != NULL) {
  		/* reduce ref-count */
  		SCTP_INP_WLOCK(inp_decr);
  		SCTP_INP_DECR_REF(inp_decr);
  		SCTP_INP_WUNLOCK(inp_decr);
  	}
  	return;
  }
  
  #ifdef INET
  #if !defined(__Userspace__)
  #if defined(__FreeBSD__) || defined(__APPLE__) || defined(__Windows__)
  void
  sctp_input_with_port(struct mbuf *i_pak, int off, uint16_t port)
  #elif defined(__Panda__)
  void
  sctp_input(pakhandle_type i_pak)
  #else
  void
  #if __STDC__
  sctp_input(struct mbuf *i_pak,...)
  #else
  sctp_input(i_pak, va_alist)
  	struct mbuf *i_pak;
  #endif
  #endif
  {
  	struct mbuf *m;
  	int iphlen;
  	uint32_t vrf_id = 0;
  	uint8_t ecn_bits;
  	struct sockaddr_in src, dst;
  	struct ip *ip;
  	struct sctphdr *sh;
  	struct sctp_chunkhdr *ch;
  	int length, offset;
  #if !defined(SCTP_WITH_NO_CSUM)
  	uint8_t compute_crc;
  #endif
  #if defined(__FreeBSD__)
  	uint32_t mflowid;
  	uint8_t mflowtype;
  	uint16_t fibnum;
  #endif
  #if !(defined(__FreeBSD__) || defined(__APPLE__) || defined(__Windows__))
  	uint16_t port = 0;
  #endif
  
  #if defined(__Panda__)
  	/* This is Evil, but its the only way to make panda work right. */
  	iphlen = sizeof(struct ip);
  #else
  	iphlen = off;
  #endif
  	if (SCTP_GET_PKT_VRFID(i_pak, vrf_id)) {
  		SCTP_RELEASE_PKT(i_pak);
  		return;
  	}
  	m = SCTP_HEADER_TO_CHAIN(i_pak);
  #ifdef __Panda__
  	SCTP_DETACH_HEADER_FROM_CHAIN(i_pak);
  	(void)SCTP_RELEASE_HEADER(i_pak);
  #endif
  #ifdef SCTP_MBUF_LOGGING
  	/* Log in any input mbufs */
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MBUF_LOGGING_ENABLE) {
  		sctp_log_mbc(m, SCTP_MBUF_INPUT);
  	}
  #endif
  #ifdef SCTP_PACKET_LOGGING
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LAST_PACKET_TRACING) {
  		sctp_packet_log(m);
  	}
  #endif
  #if defined(__FreeBSD__)
  #if __FreeBSD_version > 1000049
  	SCTPDBG(SCTP_DEBUG_CRCOFFLOAD,
  	        "sctp_input(): Packet of length %d received on %s with csum_flags 0x%b.\n",
  	        m->m_pkthdr.len,
  	        if_name(m->m_pkthdr.rcvif),
  	        (int)m->m_pkthdr.csum_flags, CSUM_BITS);
  #elif __FreeBSD_version >= 800000
  	SCTPDBG(SCTP_DEBUG_CRCOFFLOAD,
  	        "sctp_input(): Packet of length %d received on %s with csum_flags 0x%x.\n",
  	        m->m_pkthdr.len,
  	        if_name(m->m_pkthdr.rcvif),
  	        m->m_pkthdr.csum_flags);
  #else
  	SCTPDBG(SCTP_DEBUG_CRCOFFLOAD,
  	        "sctp_input(): Packet of length %d received on %s with csum_flags 0x%x.\n",
  	        m->m_pkthdr.len,
  	        m->m_pkthdr.rcvif->if_xname,
  	        m->m_pkthdr.csum_flags);
  #endif
  #endif
  #if defined(__APPLE__)
  	SCTPDBG(SCTP_DEBUG_CRCOFFLOAD,
  	        "sctp_input(): Packet of length %d received on %s%d with csum_flags 0x%x.\n",
  	        m->m_pkthdr.len,
  	        m->m_pkthdr.rcvif->if_name,
  	        m->m_pkthdr.rcvif->if_unit,
  	        m->m_pkthdr.csum_flags);
  #endif
  #if defined(__Windows__)
  	SCTPDBG(SCTP_DEBUG_CRCOFFLOAD,
  	        "sctp_input(): Packet of length %d received on %s with csum_flags 0x%x.\n",
  	        m->m_pkthdr.len,
  	        m->m_pkthdr.rcvif->if_xname,
  	        m->m_pkthdr.csum_flags);
  #endif
  #if defined(__FreeBSD__)
  	mflowid = m->m_pkthdr.flowid;
  	mflowtype = M_HASHTYPE_GET(m);
  	fibnum = M_GETFIB(m);
  #endif
  	SCTP_STAT_INCR(sctps_recvpackets);
  	SCTP_STAT_INCR_COUNTER64(sctps_inpackets);
  	/* Get IP, SCTP, and first chunk header together in the first mbuf. */
  	offset = iphlen + sizeof(struct sctphdr) + sizeof(struct sctp_chunkhdr);
  	if (SCTP_BUF_LEN(m) < offset) {
  		if ((m = m_pullup(m, offset)) == NULL) {
  			SCTP_STAT_INCR(sctps_hdrops);
  			return;
  		}
  	}
  	ip = mtod(m, struct ip *);
  	sh = (struct sctphdr *)((caddr_t)ip + iphlen);
  	ch = (struct sctp_chunkhdr *)((caddr_t)sh + sizeof(struct sctphdr));
  	offset -= sizeof(struct sctp_chunkhdr);
  	memset(&src, 0, sizeof(struct sockaddr_in));
  	src.sin_family = AF_INET;
  #ifdef HAVE_SIN_LEN
  	src.sin_len = sizeof(struct sockaddr_in);
  #endif
  	src.sin_port = sh->src_port;
  	src.sin_addr = ip->ip_src;
  	memset(&dst, 0, sizeof(struct sockaddr_in));
  	dst.sin_family = AF_INET;
  #ifdef HAVE_SIN_LEN
  	dst.sin_len = sizeof(struct sockaddr_in);
  #endif
  	dst.sin_port = sh->dest_port;
  	dst.sin_addr = ip->ip_dst;
  #if defined(__Windows__)
  	NTOHS(ip->ip_len);
  #endif
  #if defined(__Userspace_os_Linux) || defined(__Userspace_os_Windows)
  	ip->ip_len = ntohs(ip->ip_len);
  #endif
  #if defined(__FreeBSD__)
  #if __FreeBSD_version >= 1000000
  	length = ntohs(ip->ip_len);
  #else
  	length = ip->ip_len + iphlen;
  #endif
  #elif defined(__APPLE__)
  	length = ip->ip_len + iphlen;
  #elif defined(__Userspace__)
  #if defined(__Userspace_os_Linux) || defined(__Userspace_os_Windows)
  	length = ip->ip_len;
  #else
  	length = ip->ip_len + iphlen;
  #endif
  #else
  	length = ip->ip_len;
  #endif
  	/* Validate mbuf chain length with IP payload length. */
  	if (SCTP_HEADER_LEN(m) != length) {
  		SCTPDBG(SCTP_DEBUG_INPUT1,
  		        "sctp_input() length:%d reported length:%d\n", length, SCTP_HEADER_LEN(m));
  		SCTP_STAT_INCR(sctps_hdrops);
  		goto out;
  	}
  	/* SCTP does not allow broadcasts or multicasts */
  	if (IN_MULTICAST(ntohl(dst.sin_addr.s_addr))) {
  		goto out;
  	}
  	if (SCTP_IS_IT_BROADCAST(dst.sin_addr, m)) {
  		goto out;
  	}
  	ecn_bits = ip->ip_tos;
  #if defined(SCTP_WITH_NO_CSUM)
  	SCTP_STAT_INCR(sctps_recvnocrc);
  #else
  #if defined(__FreeBSD__) && __FreeBSD_version >= 800000
  	if (m->m_pkthdr.csum_flags & CSUM_SCTP_VALID) {
  		SCTP_STAT_INCR(sctps_recvhwcrc);
  		compute_crc = 0;
  	} else {
  #else
  	if (SCTP_BASE_SYSCTL(sctp_no_csum_on_loopback) &&
  	    ((src.sin_addr.s_addr == dst.sin_addr.s_addr) ||
  	     (SCTP_IS_IT_LOOPBACK(m)))) {
  		SCTP_STAT_INCR(sctps_recvnocrc);
  		compute_crc = 0;
  	} else {
  #endif
  		SCTP_STAT_INCR(sctps_recvswcrc);
  		compute_crc = 1;
  	}
  #endif
  	sctp_common_input_processing(&m, iphlen, offset, length,
  	                             (struct sockaddr *)&src,
  	                             (struct sockaddr *)&dst,
  	                             sh, ch,
  #if !defined(SCTP_WITH_NO_CSUM)
  	                             compute_crc,
  #endif
  	                             ecn_bits,
  #if defined(__FreeBSD__)
  	                             mflowtype, mflowid, fibnum,
  #endif
  	                             vrf_id, port);
   out:
  	if (m) {
  		sctp_m_freem(m);
  	}
  	return;
  }
  
  #if defined(__FreeBSD__) && defined(SCTP_MCORE_INPUT) && defined(SMP)
  extern int *sctp_cpuarry;
  #endif
  
  #if defined(__FreeBSD__) && __FreeBSD_version >= 1100020
  int
  sctp_input(struct mbuf **mp, int *offp, int proto SCTP_UNUSED)
  {
  	struct mbuf *m;
  	int off;
  
  	m = *mp;
  	off = *offp;
  #else
  void
  sctp_input(struct mbuf *m, int off)
  {
  #endif
  #if defined(__FreeBSD__) && defined(SCTP_MCORE_INPUT) && defined(SMP)
  	if (mp_ncpus > 1) {
  		struct ip *ip;
  		struct sctphdr *sh;
  		int offset;
  		int cpu_to_use;
  		uint32_t flowid, tag;
  
  		if (M_HASHTYPE_GET(m) != M_HASHTYPE_NONE) {
  			flowid = m->m_pkthdr.flowid;
  		} else {
  			/* No flow id built by lower layers
  			 * fix it so we create one.
  			 */
  			offset = off + sizeof(struct sctphdr);
  			if (SCTP_BUF_LEN(m) < offset) {
  				if ((m = m_pullup(m, offset)) == NULL) {
  					SCTP_STAT_INCR(sctps_hdrops);
  #if defined(__FreeBSD__) && __FreeBSD_version >= 1100020
  					return (IPPROTO_DONE);
  #else
  					return;
  #endif
  				}
  			}
  			ip = mtod(m, struct ip *);
  			sh = (struct sctphdr *)((caddr_t)ip + off);
  			tag = htonl(sh->v_tag);
  			flowid = tag ^ ntohs(sh->dest_port) ^ ntohs(sh->src_port);
  			m->m_pkthdr.flowid = flowid;
  			M_HASHTYPE_SET(m, M_HASHTYPE_OPAQUE_HASH);
  		}
  		cpu_to_use = sctp_cpuarry[flowid % mp_ncpus];
  		sctp_queue_to_mcore(m, off, cpu_to_use);
  #if defined(__FreeBSD__) && __FreeBSD_version >= 1100020
  		return (IPPROTO_DONE);
  #else
  		return;
  #endif
  	}
  #endif
  	sctp_input_with_port(m, off, 0);
  #if defined(__FreeBSD__) && __FreeBSD_version >= 1100020
  	return (IPPROTO_DONE);
  #endif
  }
  #endif
  #endif
  