text: /*-
   * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved.
   * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved.
   * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are met:
   *
   * a) Redistributions of source code must retain the above copyright notice,
   *    this list of conditions and the following disclaimer.
   *
   * b) Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the distribution.
   *
   * c) Neither the name of Cisco Systems, Inc. nor the names of its
   *    contributors may be used to endorse or promote products derived
   *    from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
   * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
   * THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #ifdef __FreeBSD__
  #include <sys/cdefs.h>
  __FBSDID("$FreeBSD: head/sys/netinet/sctp_indata.c 283650 2015-05-28 16:00:23Z 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_indata.h>
  #include <netinet/sctp_uio.h>
  #include <netinet/sctp_timer.h>
  
  
  /*
   * NOTES: On the outbound side of things I need to check the sack timer to
   * see if I should generate a sack into the chunk queue (if I have data to
   * send that is and will be sending it .. for bundling.
   *
   * The callback in sctp_usrreq.c will get called when the socket is read from.
   * This will cause sctp_service_queues() to get called on the top entry in
   * the list.
   */
  
  void
  sctp_set_rwnd(struct sctp_tcb *stcb, struct sctp_association *asoc)
  {
  	asoc->my_rwnd = sctp_calc_rwnd(stcb, asoc);
  }
  
  /* Calculate what the rwnd would be */
  uint32_t
  sctp_calc_rwnd(struct sctp_tcb *stcb, struct sctp_association *asoc)
  {
  	uint32_t calc = 0;
  
  	/*
  	 * This is really set wrong with respect to a 1-2-m socket. Since
  	 * the sb_cc is the count that everyone as put up. When we re-write
  	 * sctp_soreceive then we will fix this so that ONLY this
  	 * associations data is taken into account.
  	 */
  	if (stcb->sctp_socket == NULL)
  		return (calc);
  
  	if (stcb->asoc.sb_cc == 0 &&
  	    asoc->size_on_reasm_queue == 0 &&
  	    asoc->size_on_all_streams == 0) {
  		/* Full rwnd granted */
  		calc = max(SCTP_SB_LIMIT_RCV(stcb->sctp_socket), SCTP_MINIMAL_RWND);
  		return (calc);
  	}
  	/* get actual space */
  	calc = (uint32_t) sctp_sbspace(&stcb->asoc, &stcb->sctp_socket->so_rcv);
  
  	/*
  	 * take out what has NOT been put on socket queue and we yet hold
  	 * for putting up.
  	 */
  	calc = sctp_sbspace_sub(calc, (uint32_t)(asoc->size_on_reasm_queue +
  	                                         asoc->cnt_on_reasm_queue * MSIZE));
  	calc = sctp_sbspace_sub(calc, (uint32_t)(asoc->size_on_all_streams +
  	                                         asoc->cnt_on_all_streams * MSIZE));
  
  	if (calc == 0) {
  		/* out of space */
  		return (calc);
  	}
  
  	/* what is the overhead of all these rwnd's */
  	calc = sctp_sbspace_sub(calc, stcb->asoc.my_rwnd_control_len);
  	/* If the window gets too small due to ctrl-stuff, reduce it
  	 * to 1, even it is 0. SWS engaged
  	 */
  	if (calc < stcb->asoc.my_rwnd_control_len) {
  		calc = 1;
  	}
  	return (calc);
  }
  
  
  
  /*
   * Build out our readq entry based on the incoming packet.
   */
  struct sctp_queued_to_read *
  sctp_build_readq_entry(struct sctp_tcb *stcb,
      struct sctp_nets *net,
      uint32_t tsn, uint32_t ppid,
      uint32_t context, uint16_t stream_no,
      uint16_t stream_seq, uint8_t flags,
      struct mbuf *dm)
  {
  	struct sctp_queued_to_read *read_queue_e = NULL;
  
  	sctp_alloc_a_readq(stcb, read_queue_e);
  	if (read_queue_e == NULL) {
  		goto failed_build;
  	}
  	read_queue_e->sinfo_stream = stream_no;
  	read_queue_e->sinfo_ssn = stream_seq;
  	read_queue_e->sinfo_flags = (flags << 8);
  	read_queue_e->sinfo_ppid = ppid;
  	read_queue_e->sinfo_context = context;
  	read_queue_e->sinfo_timetolive = 0;
  	read_queue_e->sinfo_tsn = tsn;
  	read_queue_e->sinfo_cumtsn = tsn;
  	read_queue_e->sinfo_assoc_id = sctp_get_associd(stcb);
  	read_queue_e->whoFrom = net;
  	read_queue_e->length = 0;
  	atomic_add_int(&net->ref_count, 1);
  	read_queue_e->data = dm;
  	read_queue_e->spec_flags = 0;
  	read_queue_e->tail_mbuf = NULL;
  	read_queue_e->aux_data = NULL;
  	read_queue_e->stcb = stcb;
  	read_queue_e->port_from = stcb->rport;
  	read_queue_e->do_not_ref_stcb = 0;
  	read_queue_e->end_added = 0;
  	read_queue_e->some_taken = 0;
  	read_queue_e->pdapi_aborted = 0;
  failed_build:
  	return (read_queue_e);
  }
  
  
  /*
   * Build out our readq entry based on the incoming packet.
   */
  static struct sctp_queued_to_read *
  sctp_build_readq_entry_chk(struct sctp_tcb *stcb,
      struct sctp_tmit_chunk *chk)
  {
  	struct sctp_queued_to_read *read_queue_e = NULL;
  
  	sctp_alloc_a_readq(stcb, read_queue_e);
  	if (read_queue_e == NULL) {
  		goto failed_build;
  	}
  	read_queue_e->sinfo_stream = chk->rec.data.stream_number;
  	read_queue_e->sinfo_ssn = chk->rec.data.stream_seq;
  	read_queue_e->sinfo_flags = (chk->rec.data.rcv_flags << 8);
  	read_queue_e->sinfo_ppid = chk->rec.data.payloadtype;
  	read_queue_e->sinfo_context = stcb->asoc.context;
  	read_queue_e->sinfo_timetolive = 0;
  	read_queue_e->sinfo_tsn = chk->rec.data.TSN_seq;
  	read_queue_e->sinfo_cumtsn = chk->rec.data.TSN_seq;
  	read_queue_e->sinfo_assoc_id = sctp_get_associd(stcb);
  	read_queue_e->whoFrom = chk->whoTo;
  	read_queue_e->aux_data = NULL;
  	read_queue_e->length = 0;
  	atomic_add_int(&chk->whoTo->ref_count, 1);
  	read_queue_e->data = chk->data;
  	read_queue_e->tail_mbuf = NULL;
  	read_queue_e->stcb = stcb;
  	read_queue_e->port_from = stcb->rport;
  	read_queue_e->spec_flags = 0;
  	read_queue_e->do_not_ref_stcb = 0;
  	read_queue_e->end_added = 0;
  	read_queue_e->some_taken = 0;
  	read_queue_e->pdapi_aborted = 0;
  failed_build:
  	return (read_queue_e);
  }
  
  
  struct mbuf *
  sctp_build_ctl_nchunk(struct sctp_inpcb *inp, struct sctp_sndrcvinfo *sinfo)
  {
  	struct sctp_extrcvinfo *seinfo;
  	struct sctp_sndrcvinfo *outinfo;
  	struct sctp_rcvinfo *rcvinfo;
  	struct sctp_nxtinfo *nxtinfo;
  #if defined(__Userspace_os_Windows)
  	WSACMSGHDR *cmh;
  #else
  	struct cmsghdr *cmh;
  #endif
  	struct mbuf *ret;
  	int len;
  	int use_extended;
  	int provide_nxt;
  
  	if (sctp_is_feature_off(inp, SCTP_PCB_FLAGS_RECVDATAIOEVNT) &&
  	    sctp_is_feature_off(inp, SCTP_PCB_FLAGS_RECVRCVINFO) &&
  	    sctp_is_feature_off(inp, SCTP_PCB_FLAGS_RECVNXTINFO)) {
  		/* user does not want any ancillary data */
  		return (NULL);
  	}
  
  	len = 0;
  	if (sctp_is_feature_on(inp, SCTP_PCB_FLAGS_RECVRCVINFO)) {
  		len += CMSG_SPACE(sizeof(struct sctp_rcvinfo));
  	}
  	seinfo = (struct sctp_extrcvinfo *)sinfo;
  	if (sctp_is_feature_on(inp, SCTP_PCB_FLAGS_RECVNXTINFO) &&
  	    (seinfo->sreinfo_next_flags & SCTP_NEXT_MSG_AVAIL)) {
  		provide_nxt = 1;
  		len += CMSG_SPACE(sizeof(struct sctp_rcvinfo));
  	} else {
  		provide_nxt = 0;
  	}
  	if (sctp_is_feature_on(inp, SCTP_PCB_FLAGS_RECVDATAIOEVNT)) {
  		if (sctp_is_feature_on(inp, SCTP_PCB_FLAGS_EXT_RCVINFO)) {
  			use_extended = 1;
  			len += CMSG_SPACE(sizeof(struct sctp_extrcvinfo));
  		} else {
  			use_extended = 0;
  			len += CMSG_SPACE(sizeof(struct sctp_sndrcvinfo));
  		}
  	} else {
  		use_extended = 0;
  	}
  
  	ret = sctp_get_mbuf_for_msg(len, 0, M_NOWAIT, 1, MT_DATA);
  	if (ret == NULL) {
  		/* No space */
  		return (ret);
  	}
  	SCTP_BUF_LEN(ret) = 0;
  
  	/* We need a CMSG header followed by the struct */
  #if defined(__Userspace_os_Windows)
  	cmh = mtod(ret, WSACMSGHDR *);
  #else
  	cmh = mtod(ret, struct cmsghdr *);
  #endif
  	/*
  	 * Make sure that there is no un-initialized padding between
  	 * the cmsg header and cmsg data and after the cmsg data.
  	 */
  	memset(cmh, 0, len);
  	if (sctp_is_feature_on(inp, SCTP_PCB_FLAGS_RECVRCVINFO)) {
  		cmh->cmsg_level = IPPROTO_SCTP;
  		cmh->cmsg_len = CMSG_LEN(sizeof(struct sctp_rcvinfo));
  		cmh->cmsg_type = SCTP_RCVINFO;
  		rcvinfo = (struct sctp_rcvinfo *)CMSG_DATA(cmh);
  		rcvinfo->rcv_sid = sinfo->sinfo_stream;
  		rcvinfo->rcv_ssn = sinfo->sinfo_ssn;
  		rcvinfo->rcv_flags = sinfo->sinfo_flags;
  		rcvinfo->rcv_ppid = sinfo->sinfo_ppid;
  		rcvinfo->rcv_tsn = sinfo->sinfo_tsn;
  		rcvinfo->rcv_cumtsn = sinfo->sinfo_cumtsn;
  		rcvinfo->rcv_context = sinfo->sinfo_context;
  		rcvinfo->rcv_assoc_id = sinfo->sinfo_assoc_id;
  #if defined(__Userspace_os_Windows)
  		cmh = (WSACMSGHDR *)((caddr_t)cmh + CMSG_SPACE(sizeof(struct sctp_rcvinfo)));
  #else
  		cmh = (struct cmsghdr *)((caddr_t)cmh + CMSG_SPACE(sizeof(struct sctp_rcvinfo)));
  #endif
  		SCTP_BUF_LEN(ret) += CMSG_SPACE(sizeof(struct sctp_rcvinfo));
  	}
  	if (provide_nxt) {
  		cmh->cmsg_level = IPPROTO_SCTP;
  		cmh->cmsg_len = CMSG_LEN(sizeof(struct sctp_nxtinfo));
  		cmh->cmsg_type = SCTP_NXTINFO;
  		nxtinfo = (struct sctp_nxtinfo *)CMSG_DATA(cmh);
  		nxtinfo->nxt_sid = seinfo->sreinfo_next_stream;
  		nxtinfo->nxt_flags = 0;
  		if (seinfo->sreinfo_next_flags & SCTP_NEXT_MSG_IS_UNORDERED) {
  			nxtinfo->nxt_flags |= SCTP_UNORDERED;
  		}
  		if (seinfo->sreinfo_next_flags & SCTP_NEXT_MSG_IS_NOTIFICATION) {
  			nxtinfo->nxt_flags |= SCTP_NOTIFICATION;
  		}
  		if (seinfo->sreinfo_next_flags & SCTP_NEXT_MSG_ISCOMPLETE) {
  			nxtinfo->nxt_flags |= SCTP_COMPLETE;
  		}
  		nxtinfo->nxt_ppid = seinfo->sreinfo_next_ppid;
  		nxtinfo->nxt_length = seinfo->sreinfo_next_length;
  		nxtinfo->nxt_assoc_id = seinfo->sreinfo_next_aid;
  #if defined(__Userspace_os_Windows)
  		cmh = (WSACMSGHDR *)((caddr_t)cmh + CMSG_SPACE(sizeof(struct sctp_nxtinfo)));
  #else
  		cmh = (struct cmsghdr *)((caddr_t)cmh + CMSG_SPACE(sizeof(struct sctp_nxtinfo)));
  #endif
  		SCTP_BUF_LEN(ret) += CMSG_SPACE(sizeof(struct sctp_nxtinfo));
  	}
  	if (sctp_is_feature_on(inp, SCTP_PCB_FLAGS_RECVDATAIOEVNT)) {
  		cmh->cmsg_level = IPPROTO_SCTP;
  		outinfo = (struct sctp_sndrcvinfo *)CMSG_DATA(cmh);
  		if (use_extended) {
  			cmh->cmsg_len = CMSG_LEN(sizeof(struct sctp_extrcvinfo));
  			cmh->cmsg_type = SCTP_EXTRCV;
  			memcpy(outinfo, sinfo, sizeof(struct sctp_extrcvinfo));
  			SCTP_BUF_LEN(ret) += CMSG_SPACE(sizeof(struct sctp_extrcvinfo));
  		} else {
  			cmh->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo));
  			cmh->cmsg_type = SCTP_SNDRCV;
  			*outinfo = *sinfo;
  			SCTP_BUF_LEN(ret) += CMSG_SPACE(sizeof(struct sctp_sndrcvinfo));
  		}
  	}
  	return (ret);
  }
  
  
  static void
  sctp_mark_non_revokable(struct sctp_association *asoc, uint32_t tsn)
  {
  	uint32_t gap, i, cumackp1;
  	int fnd = 0;
  
  	if (SCTP_BASE_SYSCTL(sctp_do_drain) == 0) {
  		return;
  	}
  	cumackp1 = asoc->cumulative_tsn + 1;
  	if (SCTP_TSN_GT(cumackp1, tsn)) {
  		/* this tsn is behind the cum ack and thus we don't
  		 * need to worry about it being moved from one to the other.
  		 */
  		return;
  	}
  	SCTP_CALC_TSN_TO_GAP(gap, tsn, asoc->mapping_array_base_tsn);
  	if (!SCTP_IS_TSN_PRESENT(asoc->mapping_array, gap)) {
  		SCTP_PRINTF("gap:%x tsn:%x\n", gap, tsn);
  		sctp_print_mapping_array(asoc);
  #ifdef INVARIANTS
  		panic("Things are really messed up now!!");
  #endif
  	}
  	SCTP_SET_TSN_PRESENT(asoc->nr_mapping_array, gap);
  	SCTP_UNSET_TSN_PRESENT(asoc->mapping_array, gap);
  	if (SCTP_TSN_GT(tsn, asoc->highest_tsn_inside_nr_map)) {
  		asoc->highest_tsn_inside_nr_map = tsn;
  	}
  	if (tsn == asoc->highest_tsn_inside_map) {
  		/* We must back down to see what the new highest is */
  		for (i = tsn - 1; SCTP_TSN_GE(i, asoc->mapping_array_base_tsn); i--) {
  			SCTP_CALC_TSN_TO_GAP(gap, i, asoc->mapping_array_base_tsn);
  			if (SCTP_IS_TSN_PRESENT(asoc->mapping_array, gap)) {
  				asoc->highest_tsn_inside_map = i;
  				fnd = 1;
  				break;
  			}
  		}
  		if (!fnd) {
  			asoc->highest_tsn_inside_map = asoc->mapping_array_base_tsn - 1;
  		}
  	}
  }
  
  
  /*
   * We are delivering currently from the reassembly queue. We must continue to
   * deliver until we either: 1) run out of space. 2) run out of sequential
   * TSN's 3) hit the SCTP_DATA_LAST_FRAG flag.
   */
  static void
  sctp_service_reassembly(struct sctp_tcb *stcb, struct sctp_association *asoc)
  {
  	struct sctp_tmit_chunk *chk, *nchk;
  	uint16_t nxt_todel;
  	uint16_t stream_no;
  	int end = 0;
  	int cntDel;
  	struct sctp_queued_to_read *control, *ctl, *nctl;
  
  	if (stcb == NULL)
  		return;
  
  	cntDel = stream_no = 0;
  	if ((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) ||
  	     (stcb->asoc.state & SCTP_STATE_ABOUT_TO_BE_FREED) ||
  	     (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET)) {
  		/* socket above is long gone or going.. */
  	abandon:
  		asoc->fragmented_delivery_inprogress = 0;
  		TAILQ_FOREACH_SAFE(chk, &asoc->reasmqueue, sctp_next, nchk) {
  			TAILQ_REMOVE(&asoc->reasmqueue, chk, sctp_next);
  			asoc->size_on_reasm_queue -= chk->send_size;
  			sctp_ucount_decr(asoc->cnt_on_reasm_queue);
  			/*
  			 * Lose the data pointer, since its in the socket
  			 * buffer
  			 */
  			if (chk->data) {
  				sctp_m_freem(chk->data);
  				chk->data = NULL;
  			}
  			/* Now free the address and data */
  			sctp_free_a_chunk(stcb, chk, SCTP_SO_NOT_LOCKED);
  			/*sa_ignore FREED_MEMORY*/
  		}
  		return;
  	}
  	SCTP_TCB_LOCK_ASSERT(stcb);
  	TAILQ_FOREACH_SAFE(chk, &asoc->reasmqueue, sctp_next, nchk) {
  		if (chk->rec.data.TSN_seq != (asoc->tsn_last_delivered + 1)) {
  			/* Can't deliver more :< */
  			return;
  		}
  		stream_no = chk->rec.data.stream_number;
  		nxt_todel = asoc->strmin[stream_no].last_sequence_delivered + 1;
  		if (nxt_todel != chk->rec.data.stream_seq &&
  		    (chk->rec.data.rcv_flags & SCTP_DATA_UNORDERED) == 0) {
  			/*
  			 * Not the next sequence to deliver in its stream OR
  			 * unordered
  			 */
  			return;
  		}
  		if (chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) {
  
  			control = sctp_build_readq_entry_chk(stcb, chk);
  			if (control == NULL) {
  				/* out of memory? */
  				return;
  			}
  			/* save it off for our future deliveries */
  			stcb->asoc.control_pdapi = control;
  			if (chk->rec.data.rcv_flags & SCTP_DATA_LAST_FRAG)
  				end = 1;
  			else
  				end = 0;
  			sctp_mark_non_revokable(asoc, chk->rec.data.TSN_seq);
  			sctp_add_to_readq(stcb->sctp_ep,
  			                  stcb, control, &stcb->sctp_socket->so_rcv, end,
  			                  SCTP_READ_LOCK_NOT_HELD, SCTP_SO_NOT_LOCKED);
  			cntDel++;
  		} else {
  			if (chk->rec.data.rcv_flags & SCTP_DATA_LAST_FRAG)
  				end = 1;
  			else
  				end = 0;
  			sctp_mark_non_revokable(asoc, chk->rec.data.TSN_seq);
  			if (sctp_append_to_readq(stcb->sctp_ep, stcb,
  			    stcb->asoc.control_pdapi,
  			    chk->data, end, chk->rec.data.TSN_seq,
  			    &stcb->sctp_socket->so_rcv)) {
  				/*
  				 * something is very wrong, either
  				 * control_pdapi is NULL, or the tail_mbuf
  				 * is corrupt, or there is a EOM already on
  				 * the mbuf chain.
  				 */
  				if (stcb->asoc.state & SCTP_STATE_ABOUT_TO_BE_FREED) {
  					goto abandon;
  				} else {
  #ifdef INVARIANTS
  					if ((stcb->asoc.control_pdapi == NULL)  || (stcb->asoc.control_pdapi->tail_mbuf == NULL)) {
  						panic("This should not happen control_pdapi NULL?");
  					}
  					/* if we did not panic, it was a EOM */
  					panic("Bad chunking ??");
  #else
  					if ((stcb->asoc.control_pdapi == NULL)  || (stcb->asoc.control_pdapi->tail_mbuf == NULL)) {
  					  SCTP_PRINTF("This should not happen control_pdapi NULL?\n");
  					}
  					SCTP_PRINTF("Bad chunking ??\n");
  					SCTP_PRINTF("Dumping re-assembly queue this will probably hose the association\n");
  
  #endif
  					goto abandon;
  				}
  			}
  			cntDel++;
  		}
  		/* pull it we did it */
  		TAILQ_REMOVE(&asoc->reasmqueue, chk, sctp_next);
  		if (chk->rec.data.rcv_flags & SCTP_DATA_LAST_FRAG) {
  			asoc->fragmented_delivery_inprogress = 0;
  			if ((chk->rec.data.rcv_flags & SCTP_DATA_UNORDERED) == 0) {
  				asoc->strmin[stream_no].last_sequence_delivered++;
  			}
  			if ((chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) == 0) {
  				SCTP_STAT_INCR_COUNTER64(sctps_reasmusrmsgs);
  			}
  		} else if (chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) {
  			/*
  			 * turn the flag back on since we just  delivered
  			 * yet another one.
  			 */
  			asoc->fragmented_delivery_inprogress = 1;
  		}
  		asoc->tsn_of_pdapi_last_delivered = chk->rec.data.TSN_seq;
  		asoc->last_flags_delivered = chk->rec.data.rcv_flags;
  		asoc->last_strm_seq_delivered = chk->rec.data.stream_seq;
  		asoc->last_strm_no_delivered = chk->rec.data.stream_number;
  
  		asoc->tsn_last_delivered = chk->rec.data.TSN_seq;
  		asoc->size_on_reasm_queue -= chk->send_size;
  		sctp_ucount_decr(asoc->cnt_on_reasm_queue);
  		/* free up the chk */
  		chk->data = NULL;
  		sctp_free_a_chunk(stcb, chk, SCTP_SO_NOT_LOCKED);
  
  		if (asoc->fragmented_delivery_inprogress == 0) {
  			/*
  			 * Now lets see if we can deliver the next one on
  			 * the stream
  			 */
  			struct sctp_stream_in *strm;
  
  			strm = &asoc->strmin[stream_no];
  			nxt_todel = strm->last_sequence_delivered + 1;
  			TAILQ_FOREACH_SAFE(ctl, &strm->inqueue, next, nctl) {
  				/* Deliver more if we can. */
  				if (nxt_todel == ctl->sinfo_ssn) {
  					TAILQ_REMOVE(&strm->inqueue, ctl, next);
  					asoc->size_on_all_streams -= ctl->length;
  					sctp_ucount_decr(asoc->cnt_on_all_streams);
  					strm->last_sequence_delivered++;
  					sctp_mark_non_revokable(asoc, ctl->sinfo_tsn);
  					sctp_add_to_readq(stcb->sctp_ep, stcb,
  					                  ctl,
  					                  &stcb->sctp_socket->so_rcv, 1,
  					                  SCTP_READ_LOCK_NOT_HELD, SCTP_SO_NOT_LOCKED);
  				} else {
  					break;
  				}
  				nxt_todel = strm->last_sequence_delivered + 1;
  			}
  			break;
  		}
  	}
  }
  
  /*
   * Queue the chunk either right into the socket buffer if it is the next one
   * to go OR put it in the correct place in the delivery queue.  If we do
   * append to the so_buf, keep doing so until we are out of order. One big
   * question still remains, what to do when the socket buffer is FULL??
   */
  static void
  sctp_queue_data_to_stream(struct sctp_tcb *stcb, struct sctp_association *asoc,
      struct sctp_queued_to_read *control, int *abort_flag)
  {
  	/*
  	 * FIX-ME maybe? What happens when the ssn wraps? If we are getting
  	 * all the data in one stream this could happen quite rapidly. One
  	 * could use the TSN to keep track of things, but this scheme breaks
  	 * down in the other type of stream useage that could occur. Send a
  	 * single msg to stream 0, send 4Billion messages to stream 1, now
  	 * send a message to stream 0. You have a situation where the TSN
  	 * has wrapped but not in the stream. Is this worth worrying about
  	 * or should we just change our queue sort at the bottom to be by
  	 * TSN.
  	 *
  	 * Could it also be legal for a peer to send ssn 1 with TSN 2 and ssn 2
  	 * with TSN 1? If the peer is doing some sort of funky TSN/SSN
  	 * assignment this could happen... and I don't see how this would be
  	 * a violation. So for now I am undecided an will leave the sort by
  	 * SSN alone. Maybe a hybred approach is the answer
  	 *
  	 */
  	struct sctp_stream_in *strm;
  	struct sctp_queued_to_read *at;
  	int queue_needed;
  	uint16_t nxt_todel;
  	struct mbuf *op_err;
  	char msg[SCTP_DIAG_INFO_LEN];
  
  	queue_needed = 1;
  	asoc->size_on_all_streams += control->length;
  	sctp_ucount_incr(asoc->cnt_on_all_streams);
  	strm = &asoc->strmin[control->sinfo_stream];
  	nxt_todel = strm->last_sequence_delivered + 1;
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_STR_LOGGING_ENABLE) {
  		sctp_log_strm_del(control, NULL, SCTP_STR_LOG_FROM_INTO_STRD);
  	}
  	SCTPDBG(SCTP_DEBUG_INDATA1,
  		"queue to stream called for ssn:%u lastdel:%u nxt:%u\n",
  		(uint32_t) control->sinfo_stream,
  		(uint32_t) strm->last_sequence_delivered,
  		(uint32_t) nxt_todel);
  	if (SCTP_SSN_GE(strm->last_sequence_delivered, control->sinfo_ssn)) {
  		/* The incoming sseq is behind where we last delivered? */
  		SCTPDBG(SCTP_DEBUG_INDATA1, "Duplicate S-SEQ:%d delivered:%d from peer, Abort association\n",
  			control->sinfo_ssn, strm->last_sequence_delivered);
  	protocol_error:
  		/*
  		 * throw it in the stream so it gets cleaned up in
  		 * association destruction
  		 */
  		TAILQ_INSERT_HEAD(&strm->inqueue, control, next);
  		snprintf(msg, sizeof(msg), "Delivered SSN=%4.4x, got TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  		         strm->last_sequence_delivered, control->sinfo_tsn,
  			 control->sinfo_stream, control->sinfo_ssn);
  		op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  		stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_1;
  		sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  		*abort_flag = 1;
  		return;
  
  	}
  	if (nxt_todel == control->sinfo_ssn) {
  		/* can be delivered right away? */
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_STR_LOGGING_ENABLE) {
  			sctp_log_strm_del(control, NULL, SCTP_STR_LOG_FROM_IMMED_DEL);
  		}
  		/* EY it wont be queued if it could be delivered directly*/
  		queue_needed = 0;
  		asoc->size_on_all_streams -= control->length;
  		sctp_ucount_decr(asoc->cnt_on_all_streams);
  		strm->last_sequence_delivered++;
  
  		sctp_mark_non_revokable(asoc, control->sinfo_tsn);
  		sctp_add_to_readq(stcb->sctp_ep, stcb,
  		                  control,
  		                  &stcb->sctp_socket->so_rcv, 1,
  		                  SCTP_READ_LOCK_NOT_HELD, SCTP_SO_NOT_LOCKED);
  		TAILQ_FOREACH_SAFE(control, &strm->inqueue, next, at) {
  			/* all delivered */
  			nxt_todel = strm->last_sequence_delivered + 1;
  			if (nxt_todel == control->sinfo_ssn) {
  				TAILQ_REMOVE(&strm->inqueue, control, next);
  				asoc->size_on_all_streams -= control->length;
  				sctp_ucount_decr(asoc->cnt_on_all_streams);
  				strm->last_sequence_delivered++;
  				/*
  				 * We ignore the return of deliver_data here
  				 * since we always can hold the chunk on the
  				 * d-queue. And we have a finite number that
  				 * can be delivered from the strq.
  				 */
  				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_STR_LOGGING_ENABLE) {
  					sctp_log_strm_del(control, NULL,
  							  SCTP_STR_LOG_FROM_IMMED_DEL);
  				}
  				sctp_mark_non_revokable(asoc, control->sinfo_tsn);
  				sctp_add_to_readq(stcb->sctp_ep, stcb,
  				                  control,
  				                  &stcb->sctp_socket->so_rcv, 1,
  				                  SCTP_READ_LOCK_NOT_HELD,
  				                  SCTP_SO_NOT_LOCKED);
  				continue;
  			}
  			break;
  		}
  	}
  	if (queue_needed) {
  		/*
  		 * Ok, we did not deliver this guy, find the correct place
  		 * to put it on the queue.
  		 */
  		if (SCTP_TSN_GE(asoc->cumulative_tsn, control->sinfo_tsn)) {
  			goto protocol_error;
  		}
  		if (TAILQ_EMPTY(&strm->inqueue)) {
  			/* Empty queue */
  			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_STR_LOGGING_ENABLE) {
  				sctp_log_strm_del(control, NULL, SCTP_STR_LOG_FROM_INSERT_HD);
  			}
  			TAILQ_INSERT_HEAD(&strm->inqueue, control, next);
  		} else {
  			TAILQ_FOREACH(at, &strm->inqueue, next) {
  				if (SCTP_SSN_GT(at->sinfo_ssn, control->sinfo_ssn)) {
  					/*
  					 * one in queue is bigger than the
  					 * new one, insert before this one
  					 */
  					if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_STR_LOGGING_ENABLE) {
  						sctp_log_strm_del(control, at,
  								  SCTP_STR_LOG_FROM_INSERT_MD);
  					}
  					TAILQ_INSERT_BEFORE(at, control, next);
  					break;
  				} else if (at->sinfo_ssn == control->sinfo_ssn) {
  					/*
  					 * Gak, He sent me a duplicate str
  					 * seq number
  					 */
  					/*
  					 * foo bar, I guess I will just free
  					 * this new guy, should we abort
  					 * too? FIX ME MAYBE? Or it COULD be
  					 * that the SSN's have wrapped.
  					 * Maybe I should compare to TSN
  					 * somehow... sigh for now just blow
  					 * away the chunk!
  					 */
  
  					if (control->data)
  						sctp_m_freem(control->data);
  					control->data = NULL;
  					asoc->size_on_all_streams -= control->length;
  					sctp_ucount_decr(asoc->cnt_on_all_streams);
  					if (control->whoFrom) {
  						sctp_free_remote_addr(control->whoFrom);
  						control->whoFrom = NULL;
  					}
  					sctp_free_a_readq(stcb, control);
  					return;
  				} else {
  					if (TAILQ_NEXT(at, next) == NULL) {
  						/*
  						 * We are at the end, insert
  						 * it after this one
  						 */
  						if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_STR_LOGGING_ENABLE) {
  							sctp_log_strm_del(control, at,
  									  SCTP_STR_LOG_FROM_INSERT_TL);
  						}
  						TAILQ_INSERT_AFTER(&strm->inqueue,
  						    at, control, next);
  						break;
  					}
  				}
  			}
  		}
  	}
  }
  
  /*
   * Returns two things: You get the total size of the deliverable parts of the
   * first fragmented message on the reassembly queue. And you get a 1 back if
   * all of the message is ready or a 0 back if the message is still incomplete
   */
  static int
  sctp_is_all_msg_on_reasm(struct sctp_association *asoc, uint32_t *t_size)
  {
  	struct sctp_tmit_chunk *chk;
  	uint32_t tsn;
  
  	*t_size = 0;
  	chk = TAILQ_FIRST(&asoc->reasmqueue);
  	if (chk == NULL) {
  		/* nothing on the queue */
  		return (0);
  	}
  	if ((chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) == 0) {
  		/* Not a first on the queue */
  		return (0);
  	}
  	tsn = chk->rec.data.TSN_seq;
  	TAILQ_FOREACH(chk, &asoc->reasmqueue, sctp_next) {
  		if (tsn != chk->rec.data.TSN_seq) {
  			return (0);
  		}
  		*t_size += chk->send_size;
  		if (chk->rec.data.rcv_flags & SCTP_DATA_LAST_FRAG) {
  			return (1);
  		}
  		tsn++;
  	}
  	return (0);
  }
  
  static void
  sctp_deliver_reasm_check(struct sctp_tcb *stcb, struct sctp_association *asoc)
  {
  	struct sctp_tmit_chunk *chk;
  	uint16_t nxt_todel;
  	uint32_t tsize, pd_point;
  
   doit_again:
  	chk = TAILQ_FIRST(&asoc->reasmqueue);
  	if (chk == NULL) {
  		/* Huh? */
  		asoc->size_on_reasm_queue = 0;
  		asoc->cnt_on_reasm_queue = 0;
  		return;
  	}
  	if (asoc->fragmented_delivery_inprogress == 0) {
  		nxt_todel =
  		    asoc->strmin[chk->rec.data.stream_number].last_sequence_delivered + 1;
  		if ((chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) &&
  		    (nxt_todel == chk->rec.data.stream_seq ||
  		    (chk->rec.data.rcv_flags & SCTP_DATA_UNORDERED))) {
  			/*
  			 * Yep the first one is here and its ok to deliver
  			 * but should we?
  			 */
  			if (stcb->sctp_socket) {
  				pd_point = min(SCTP_SB_LIMIT_RCV(stcb->sctp_socket) >> SCTP_PARTIAL_DELIVERY_SHIFT,
  				               stcb->sctp_ep->partial_delivery_point);
  			} else {
  				pd_point = stcb->sctp_ep->partial_delivery_point;
  			}
  			if (sctp_is_all_msg_on_reasm(asoc, &tsize) || (tsize >= pd_point)) {
  				/*
  				 * Yes, we setup to start reception, by
  				 * backing down the TSN just in case we
  				 * can't deliver. If we
  				 */
  				asoc->fragmented_delivery_inprogress = 1;
  				asoc->tsn_last_delivered =
  				    chk->rec.data.TSN_seq - 1;
  				asoc->str_of_pdapi =
  				    chk->rec.data.stream_number;
  				asoc->ssn_of_pdapi = chk->rec.data.stream_seq;
  				asoc->pdapi_ppid = chk->rec.data.payloadtype;
  				asoc->fragment_flags = chk->rec.data.rcv_flags;
  				sctp_service_reassembly(stcb, asoc);
  			}
  		}
  	} else {
  		/* Service re-assembly will deliver stream data queued
  		 * at the end of fragmented delivery.. but it wont know
  		 * to go back and call itself again... we do that here
  		 * with the got doit_again
  		 */
  		sctp_service_reassembly(stcb, asoc);
  		if (asoc->fragmented_delivery_inprogress == 0) {
  			/* finished our Fragmented delivery, could be
  			 * more waiting?
  			 */
  			goto doit_again;
  		}
  	}
  }
  
  /*
   * Dump onto the re-assembly queue, in its proper place. After dumping on the
   * queue, see if anthing can be delivered. If so pull it off (or as much as
   * we can. If we run out of space then we must dump what we can and set the
   * appropriate flag to say we queued what we could.
   */
  static void
  sctp_queue_data_for_reasm(struct sctp_tcb *stcb, struct sctp_association *asoc,
      struct sctp_tmit_chunk *chk, int *abort_flag)
  {
  	struct mbuf *op_err;
  	char msg[SCTP_DIAG_INFO_LEN];
  	uint32_t cum_ackp1, prev_tsn, post_tsn;
  	struct sctp_tmit_chunk *at, *prev, *next;
  
  	prev = next = NULL;
  	cum_ackp1 = asoc->tsn_last_delivered + 1;
  	if (TAILQ_EMPTY(&asoc->reasmqueue)) {
  		/* This is the first one on the queue */
  		TAILQ_INSERT_HEAD(&asoc->reasmqueue, chk, sctp_next);
  		/*
  		 * we do not check for delivery of anything when only one
  		 * fragment is here
  		 */
  		asoc->size_on_reasm_queue = chk->send_size;
  		sctp_ucount_incr(asoc->cnt_on_reasm_queue);
  		if (chk->rec.data.TSN_seq == cum_ackp1) {
  			if (asoc->fragmented_delivery_inprogress == 0 &&
  			    (chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) !=
  			    SCTP_DATA_FIRST_FRAG) {
  				/*
  				 * An empty queue, no delivery inprogress,
  				 * we hit the next one and it does NOT have
  				 * a FIRST fragment mark.
  				 */
  				SCTPDBG(SCTP_DEBUG_INDATA1, "Gak, Evil plot, its not first, no fragmented delivery in progress\n");
  				snprintf(msg, sizeof(msg),
  				         "Expected B-bit for TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  				         chk->rec.data.TSN_seq,
  				         chk->rec.data.stream_number,
  				         chk->rec.data.stream_seq);
  				op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  				stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_2;
  				sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  				*abort_flag = 1;
  			} else if (asoc->fragmented_delivery_inprogress &&
  			    (chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) == SCTP_DATA_FIRST_FRAG) {
  				/*
  				 * We are doing a partial delivery and the
  				 * NEXT chunk MUST be either the LAST or
  				 * MIDDLE fragment NOT a FIRST
  				 */
  				SCTPDBG(SCTP_DEBUG_INDATA1, "Gak, Evil plot, it IS a first and fragmented delivery in progress\n");
  				snprintf(msg, sizeof(msg),
  				         "Didn't expect B-bit for TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  				         chk->rec.data.TSN_seq,
  				         chk->rec.data.stream_number,
  				         chk->rec.data.stream_seq);
  				op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  				stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_3;
  				sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  				*abort_flag = 1;
  			} else if (asoc->fragmented_delivery_inprogress) {
  				/*
  				 * Here we are ok with a MIDDLE or LAST
  				 * piece
  				 */
  				if (chk->rec.data.stream_number !=
  				    asoc->str_of_pdapi) {
  					/* Got to be the right STR No */
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Gak, Evil plot, it IS not same stream number %d vs %d\n",
  						chk->rec.data.stream_number,
  						asoc->str_of_pdapi);
  					snprintf(msg, sizeof(msg),
  					         "Expected SID=%4.4x, got TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  					         asoc->str_of_pdapi,
  					         chk->rec.data.TSN_seq,
  					         chk->rec.data.stream_number,
  					         chk->rec.data.stream_seq);
  					op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_4;
  					sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  					*abort_flag = 1;
  				} else if ((asoc->fragment_flags & SCTP_DATA_UNORDERED) !=
  					    SCTP_DATA_UNORDERED &&
  					    chk->rec.data.stream_seq != asoc->ssn_of_pdapi) {
  					/* Got to be the right STR Seq */
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Gak, Evil plot, it IS not same stream seq %d vs %d\n",
  						chk->rec.data.stream_seq,
  						asoc->ssn_of_pdapi);
  					snprintf(msg, sizeof(msg),
  					         "Expected SSN=%4.4x, got TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  					         asoc->ssn_of_pdapi,
  					         chk->rec.data.TSN_seq,
  					         chk->rec.data.stream_number,
  					         chk->rec.data.stream_seq);
  					op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_5;
  					sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  					*abort_flag = 1;
  				}
  			}
  		}
  		return;
  	}
  	/* Find its place */
  	TAILQ_FOREACH(at, &asoc->reasmqueue, sctp_next) {
  		if (SCTP_TSN_GT(at->rec.data.TSN_seq, chk->rec.data.TSN_seq)) {
  			/*
  			 * one in queue is bigger than the new one, insert
  			 * before this one
  			 */
  			/* A check */
  			asoc->size_on_reasm_queue += chk->send_size;
  			sctp_ucount_incr(asoc->cnt_on_reasm_queue);
  			next = at;
  			TAILQ_INSERT_BEFORE(at, chk, sctp_next);
  			break;
  		} else if (at->rec.data.TSN_seq == chk->rec.data.TSN_seq) {
  			/* Gak, He sent me a duplicate str seq number */
  			/*
  			 * foo bar, I guess I will just free this new guy,
  			 * should we abort too? FIX ME MAYBE? Or it COULD be
  			 * that the SSN's have wrapped. Maybe I should
  			 * compare to TSN somehow... sigh for now just blow
  			 * away the chunk!
  			 */
  			if (chk->data) {
  				sctp_m_freem(chk->data);
  				chk->data = NULL;
  			}
  			sctp_free_a_chunk(stcb, chk, SCTP_SO_NOT_LOCKED);
  			return;
  		} else {
  			prev = at;
  			if (TAILQ_NEXT(at, sctp_next) == NULL) {
  				/*
  				 * We are at the end, insert it after this
  				 * one
  				 */
  				/* check it first */
  				asoc->size_on_reasm_queue += chk->send_size;
  				sctp_ucount_incr(asoc->cnt_on_reasm_queue);
  				TAILQ_INSERT_AFTER(&asoc->reasmqueue, at, chk, sctp_next);
  				break;
  			}
  		}
  	}
  	/* Now the audits */
  	if (prev) {
  		prev_tsn = chk->rec.data.TSN_seq - 1;
  		if (prev_tsn == prev->rec.data.TSN_seq) {
  			/*
  			 * Ok the one I am dropping onto the end is the
  			 * NEXT. A bit of valdiation here.
  			 */
  			if ((prev->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) ==
  			    SCTP_DATA_FIRST_FRAG ||
  			    (prev->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) ==
  			    SCTP_DATA_MIDDLE_FRAG) {
  				/*
  				 * Insert chk MUST be a MIDDLE or LAST
  				 * fragment
  				 */
  				if ((chk->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) ==
  				    SCTP_DATA_FIRST_FRAG) {
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Prev check - It can be a midlle or last but not a first\n");
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Gak, Evil plot, it's a FIRST!\n");
  					snprintf(msg, sizeof(msg),
  					         "Can't handle B-bit, got TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  					         chk->rec.data.TSN_seq,
  					         chk->rec.data.stream_number,
  					         chk->rec.data.stream_seq);
  					op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_6;
  					sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  					*abort_flag = 1;
  					return;
  				}
  				if (chk->rec.data.stream_number !=
  				    prev->rec.data.stream_number) {
  					/*
  					 * Huh, need the correct STR here,
  					 * they must be the same.
  					 */
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Prev check - Gak, Evil plot, sid:%d not the same as at:%d\n",
  					        chk->rec.data.stream_number,
  					        prev->rec.data.stream_number);
  					snprintf(msg, sizeof(msg),
  					         "Expect SID=%4.4x, got TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  					         prev->rec.data.stream_number,
  					         chk->rec.data.TSN_seq,
  					         chk->rec.data.stream_number,
  					         chk->rec.data.stream_seq);
  					op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_7;
  					sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  					*abort_flag = 1;
  					return;
  				}
  				if ((chk->rec.data.rcv_flags & SCTP_DATA_UNORDERED) !=
  				    (prev->rec.data.rcv_flags & SCTP_DATA_UNORDERED)) {
  					/*
  					 * Huh, need the same ordering here,
  					 * they must be the same.
  					 */
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Prev check - Gak, Evil plot, U-bit not constant\n");
  					snprintf(msg, sizeof(msg),
  					         "Expect U-bit=%d for TSN=%8.8x, got U-bit=%d",
  					         (prev->rec.data.rcv_flags & SCTP_DATA_UNORDERED) ? 1 : 0,
  					         chk->rec.data.TSN_seq,
  					         (chk->rec.data.rcv_flags & SCTP_DATA_UNORDERED) ? 1 : 0);
  					op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_8;
  					sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  					*abort_flag = 1;
  					return;
  				}
  				if ((prev->rec.data.rcv_flags & SCTP_DATA_UNORDERED) == 0 &&
  				    chk->rec.data.stream_seq !=
  				    prev->rec.data.stream_seq) {
  					/*
  					 * Huh, need the correct STR here,
  					 * they must be the same.
  					 */
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Prev check - Gak, Evil plot, sseq:%d not the same as at:%d\n",
  						chk->rec.data.stream_seq,
  						prev->rec.data.stream_seq);
  					snprintf(msg, sizeof(msg),
  					         "Expect SSN=%4.4x, got TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  					         prev->rec.data.stream_seq,
  					         chk->rec.data.TSN_seq,
  					         chk->rec.data.stream_number,
  					         chk->rec.data.stream_seq);
  					op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_9;
  					sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  					*abort_flag = 1;
  					return;
  				}
  			} else if ((prev->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) ==
  			    SCTP_DATA_LAST_FRAG) {
  				/* Insert chk MUST be a FIRST */
  				if ((chk->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) !=
  				    SCTP_DATA_FIRST_FRAG) {
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Prev check - Gak, evil plot, its not FIRST and it must be!\n");
  					snprintf(msg, sizeof(msg),
  					         "Expect B-bit, got TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  					         chk->rec.data.TSN_seq,
  					         chk->rec.data.stream_number,
  					         chk->rec.data.stream_seq);
  					op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_10;
  					sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  					*abort_flag = 1;
  					return;
  				}
  			}
  		}
  	}
  	if (next) {
  		post_tsn = chk->rec.data.TSN_seq + 1;
  		if (post_tsn == next->rec.data.TSN_seq) {
  			/*
  			 * Ok the one I am inserting ahead of is my NEXT
  			 * one. A bit of valdiation here.
  			 */
  			if (next->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) {
  				/* Insert chk MUST be a last fragment */
  				if ((chk->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK)
  				    != SCTP_DATA_LAST_FRAG) {
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Next chk - Next is FIRST, we must be LAST\n");
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Gak, Evil plot, its not a last!\n");
  					snprintf(msg, sizeof(msg),
  					         "Expect only E-bit, got TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  					         chk->rec.data.TSN_seq,
  					         chk->rec.data.stream_number,
  					         chk->rec.data.stream_seq);
  					op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_11;
  					sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  					*abort_flag = 1;
  					return;
  				}
  			} else if ((next->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) ==
  				    SCTP_DATA_MIDDLE_FRAG ||
  				    (next->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) ==
  			    SCTP_DATA_LAST_FRAG) {
  				/*
  				 * Insert chk CAN be MIDDLE or FIRST NOT
  				 * LAST
  				 */
  				if ((chk->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) ==
  				    SCTP_DATA_LAST_FRAG) {
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Next chk - Next is a MIDDLE/LAST\n");
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Gak, Evil plot, new prev chunk is a LAST\n");
  					snprintf(msg, sizeof(msg),
  					         "Didn't expect E-bit, got TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  					         chk->rec.data.TSN_seq,
  					         chk->rec.data.stream_number,
  					         chk->rec.data.stream_seq);
  					op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_12;
  					sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  					*abort_flag = 1;
  					return;
  				}
  				if (chk->rec.data.stream_number !=
  				    next->rec.data.stream_number) {
  					/*
  					 * Huh, need the correct STR here,
  					 * they must be the same.
  					 */
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Next chk - Gak, Evil plot, ssn:%d not the same as at:%d\n",
  						chk->rec.data.stream_number,
  						next->rec.data.stream_number);
  					snprintf(msg, sizeof(msg),
  					         "Required SID %4.4x, got TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  					         next->rec.data.stream_number,
  					         chk->rec.data.TSN_seq,
  					         chk->rec.data.stream_number,
  					         chk->rec.data.stream_seq);
  					op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_13;
  					sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  					*abort_flag = 1;
  					return;
  				}
  				if ((chk->rec.data.rcv_flags & SCTP_DATA_UNORDERED) !=
  				    (next->rec.data.rcv_flags & SCTP_DATA_UNORDERED)) {
  					/*
  					 * Huh, need the same ordering here,
  					 * they must be the same.
  					 */
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Next check - Gak, Evil plot, U-bit not constant\n");
  					snprintf(msg, sizeof(msg),
  					         "Expect U-bit=%d for TSN=%8.8x, got U-bit=%d",
  					         (next->rec.data.rcv_flags & SCTP_DATA_UNORDERED) ? 1 : 0,
  					         chk->rec.data.TSN_seq,
  					         (chk->rec.data.rcv_flags & SCTP_DATA_UNORDERED) ? 1 : 0);
  					op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_14;
  					sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  					*abort_flag = 1;
  					return;
  				}
  				if ((next->rec.data.rcv_flags & SCTP_DATA_UNORDERED) == 0 &&
  				    chk->rec.data.stream_seq !=
  				    next->rec.data.stream_seq) {
  					/*
  					 * Huh, need the correct STR here,
  					 * they must be the same.
  					 */
  					SCTPDBG(SCTP_DEBUG_INDATA1, "Next chk - Gak, Evil plot, sseq:%d not the same as at:%d\n",
  						chk->rec.data.stream_seq,
  						next->rec.data.stream_seq);
  					snprintf(msg, sizeof(msg),
  					         "Required SSN %4.4x, got TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  					         next->rec.data.stream_seq,
  					         chk->rec.data.TSN_seq,
  					         chk->rec.data.stream_number,
  					         chk->rec.data.stream_seq);
  					op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_15;
  					sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  					*abort_flag = 1;
  					return;
  				}
  			}
  		}
  	}
  	/* Do we need to do some delivery? check */
  	sctp_deliver_reasm_check(stcb, asoc);
  }
  
  /*
   * This is an unfortunate routine. It checks to make sure a evil guy is not
   * stuffing us full of bad packet fragments. A broken peer could also do this
   * but this is doubtful. It is to bad I must worry about evil crackers sigh
   * :< more cycles.
   */
  static int
  sctp_does_tsn_belong_to_reasm(struct sctp_association *asoc,
      uint32_t TSN_seq)
  {
  	struct sctp_tmit_chunk *at;
  	uint32_t tsn_est;
  
  	TAILQ_FOREACH(at, &asoc->reasmqueue, sctp_next) {
  		if (SCTP_TSN_GT(TSN_seq, at->rec.data.TSN_seq)) {
  			/* is it one bigger? */
  			tsn_est = at->rec.data.TSN_seq + 1;
  			if (tsn_est == TSN_seq) {
  				/* yep. It better be a last then */
  				if ((at->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) !=
  				    SCTP_DATA_LAST_FRAG) {
  					/*
  					 * Ok this guy belongs next to a guy
  					 * that is NOT last, it should be a
  					 * middle/last, not a complete
  					 * chunk.
  					 */
  					return (1);
  				} else {
  					/*
  					 * This guy is ok since its a LAST
  					 * and the new chunk is a fully
  					 * self- contained one.
  					 */
  					return (0);
  				}
  			}
  		} else if (TSN_seq == at->rec.data.TSN_seq) {
  			/* Software error since I have a dup? */
  			return (1);
  		} else {
  			/*
  			 * Ok, 'at' is larger than new chunk but does it
  			 * need to be right before it.
  			 */
  			tsn_est = TSN_seq + 1;
  			if (tsn_est == at->rec.data.TSN_seq) {
  				/* Yep, It better be a first */
  				if ((at->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) !=
  				    SCTP_DATA_FIRST_FRAG) {
  					return (1);
  				} else {
  					return (0);
  				}
  			}
  		}
  	}
  	return (0);
  }
  
  static int
  sctp_process_a_data_chunk(struct sctp_tcb *stcb, struct sctp_association *asoc,
      struct mbuf **m, int offset, struct sctp_data_chunk *ch, int chk_length,
      struct sctp_nets *net, uint32_t *high_tsn, int *abort_flag,
      int *break_flag, int last_chunk)
  {
  	/* Process a data chunk */
  	/* struct sctp_tmit_chunk *chk; */
  	struct sctp_tmit_chunk *chk;
  	uint32_t tsn, gap;
  	struct mbuf *dmbuf;
  	int the_len;
  	int need_reasm_check = 0;
  	uint16_t strmno, strmseq;
  	struct mbuf *op_err;
  	char msg[SCTP_DIAG_INFO_LEN];
  	struct sctp_queued_to_read *control;
  	int ordered;
  	uint32_t protocol_id;
  	uint8_t chunk_flags;
  	struct sctp_stream_reset_list *liste;
  
  	chk = NULL;
  	tsn = ntohl(ch->dp.tsn);
  	chunk_flags = ch->ch.chunk_flags;
  	if ((chunk_flags & SCTP_DATA_SACK_IMMEDIATELY) == SCTP_DATA_SACK_IMMEDIATELY) {
  		asoc->send_sack = 1;
  	}
  	protocol_id = ch->dp.protocol_id;
  	ordered = ((chunk_flags & SCTP_DATA_UNORDERED) == 0);
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MAP_LOGGING_ENABLE) {
  		sctp_log_map(tsn, asoc->cumulative_tsn, asoc->highest_tsn_inside_map, SCTP_MAP_TSN_ENTERS);
  	}
  	if (stcb == NULL) {
  		return (0);
  	}
  	SCTP_LTRACE_CHK(stcb->sctp_ep, stcb, ch->ch.chunk_type, tsn);
  	if (SCTP_TSN_GE(asoc->cumulative_tsn, tsn)) {
  		/* It is a duplicate */
  		SCTP_STAT_INCR(sctps_recvdupdata);
  		if (asoc->numduptsns < SCTP_MAX_DUP_TSNS) {
  			/* Record a dup for the next outbound sack */
  			asoc->dup_tsns[asoc->numduptsns] = tsn;
  			asoc->numduptsns++;
  		}
  		asoc->send_sack = 1;
  		return (0);
  	}
  	/* Calculate the number of TSN's between the base and this TSN */
  	SCTP_CALC_TSN_TO_GAP(gap, tsn, asoc->mapping_array_base_tsn);
  	if (gap >= (SCTP_MAPPING_ARRAY << 3)) {
  		/* Can't hold the bit in the mapping at max array, toss it */
  		return (0);
  	}
  	if (gap >= (uint32_t) (asoc->mapping_array_size << 3)) {
  		SCTP_TCB_LOCK_ASSERT(stcb);
  		if (sctp_expand_mapping_array(asoc, gap)) {
  			/* Can't expand, drop it */
  			return (0);
  		}
  	}
  	if (SCTP_TSN_GT(tsn, *high_tsn)) {
  		*high_tsn = tsn;
  	}
  	/* See if we have received this one already */
  	if (SCTP_IS_TSN_PRESENT(asoc->mapping_array, gap) ||
  	    SCTP_IS_TSN_PRESENT(asoc->nr_mapping_array, gap)) {
  		SCTP_STAT_INCR(sctps_recvdupdata);
  		if (asoc->numduptsns < SCTP_MAX_DUP_TSNS) {
  			/* Record a dup for the next outbound sack */
  			asoc->dup_tsns[asoc->numduptsns] = tsn;
  			asoc->numduptsns++;
  		}
  		asoc->send_sack = 1;
  		return (0);
  	}
  	/*
  	 * Check to see about the GONE flag, duplicates would cause a sack
  	 * to be sent up above
  	 */
  	if (((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) ||
  	     (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_ALLGONE) ||
  	     (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET))) {
  		/*
  		 * wait a minute, this guy is gone, there is no longer a
  		 * receiver. Send peer an ABORT!
  		 */
  		op_err = sctp_generate_cause(SCTP_CAUSE_OUT_OF_RESC, "");
  		sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  		*abort_flag = 1;
  		return (0);
  	}
  	/*
  	 * Now before going further we see if there is room. If NOT then we
  	 * MAY let one through only IF this TSN is the one we are waiting
  	 * for on a partial delivery API.
  	 */
  
  	/* now do the tests */
  	if (((asoc->cnt_on_all_streams +
  	      asoc->cnt_on_reasm_queue +
  	      asoc->cnt_msg_on_sb) >= SCTP_BASE_SYSCTL(sctp_max_chunks_on_queue)) ||
  	    (((int)asoc->my_rwnd) <= 0)) {
  		/*
  		 * When we have NO room in the rwnd we check to make sure
  		 * the reader is doing its job...
  		 */
  		if (stcb->sctp_socket->so_rcv.sb_cc) {
  			/* some to read, wake-up */
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  			struct socket *so;
  
  			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 (0);
  			}
  #endif
  			sctp_sorwakeup(stcb->sctp_ep, stcb->sctp_socket);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  			SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  		}
  		/* now is it in the mapping array of what we have accepted? */
  		if (SCTP_TSN_GT(tsn, asoc->highest_tsn_inside_map) &&
  		    SCTP_TSN_GT(tsn, asoc->highest_tsn_inside_nr_map)) {
  			/* Nope not in the valid range dump it */
  			sctp_set_rwnd(stcb, asoc);
  			if ((asoc->cnt_on_all_streams +
  			     asoc->cnt_on_reasm_queue +
  			     asoc->cnt_msg_on_sb) >= SCTP_BASE_SYSCTL(sctp_max_chunks_on_queue)) {
  				SCTP_STAT_INCR(sctps_datadropchklmt);
  			} else {
  				SCTP_STAT_INCR(sctps_datadroprwnd);
  			}
  			*break_flag = 1;
  			return (0);
  		}
  	}
  	strmno = ntohs(ch->dp.stream_id);
  	if (strmno >= asoc->streamincnt) {
  		struct sctp_paramhdr *phdr;
  		struct mbuf *mb;
  
  		mb = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) * 2),
  					   0, M_NOWAIT, 1, MT_DATA);
  		if (mb != NULL) {
  			/* add some space up front so prepend will work well */
  			SCTP_BUF_RESV_UF(mb, sizeof(struct sctp_chunkhdr));
  			phdr = mtod(mb, struct sctp_paramhdr *);
  			/*
  			 * Error causes are just param's and this one has
  			 * two back to back phdr, one with the error type
  			 * and size, the other with the streamid and a rsvd
  			 */
  			SCTP_BUF_LEN(mb) = (sizeof(struct sctp_paramhdr) * 2);
  			phdr->param_type = htons(SCTP_CAUSE_INVALID_STREAM);
  			phdr->param_length =
  			    htons(sizeof(struct sctp_paramhdr) * 2);
  			phdr++;
  			/* We insert the stream in the type field */
  			phdr->param_type = ch->dp.stream_id;
  			/* And set the length to 0 for the rsvd field */
  			phdr->param_length = 0;
  			sctp_queue_op_err(stcb, mb);
  		}
  		SCTP_STAT_INCR(sctps_badsid);
  		SCTP_TCB_LOCK_ASSERT(stcb);
  		SCTP_SET_TSN_PRESENT(asoc->nr_mapping_array, gap);
  		if (SCTP_TSN_GT(tsn, asoc->highest_tsn_inside_nr_map)) {
  			asoc->highest_tsn_inside_nr_map = tsn;
  		}
  		if (tsn == (asoc->cumulative_tsn + 1)) {
  			/* Update cum-ack */
  			asoc->cumulative_tsn = tsn;
  		}
  		return (0);
  	}
  	/*
  	 * Before we continue lets validate that we are not being fooled by
  	 * an evil attacker. We can only have 4k chunks based on our TSN
  	 * spread allowed by the mapping array 512 * 8 bits, so there is no
  	 * way our stream sequence numbers could have wrapped. We of course
  	 * only validate the FIRST fragment so the bit must be set.
  	 */
  	strmseq = ntohs(ch->dp.stream_sequence);
  #ifdef SCTP_ASOCLOG_OF_TSNS
  	SCTP_TCB_LOCK_ASSERT(stcb);
  	if (asoc->tsn_in_at >= SCTP_TSN_LOG_SIZE) {
  		asoc->tsn_in_at = 0;
  		asoc->tsn_in_wrapped = 1;
  	}
  	asoc->in_tsnlog[asoc->tsn_in_at].tsn = tsn;
  	asoc->in_tsnlog[asoc->tsn_in_at].strm = strmno;
  	asoc->in_tsnlog[asoc->tsn_in_at].seq = strmseq;
  	asoc->in_tsnlog[asoc->tsn_in_at].sz = chk_length;
  	asoc->in_tsnlog[asoc->tsn_in_at].flgs = chunk_flags;
  	asoc->in_tsnlog[asoc->tsn_in_at].stcb = (void *)stcb;
  	asoc->in_tsnlog[asoc->tsn_in_at].in_pos = asoc->tsn_in_at;
  	asoc->in_tsnlog[asoc->tsn_in_at].in_out = 1;
  	asoc->tsn_in_at++;
  #endif
  	if ((chunk_flags & SCTP_DATA_FIRST_FRAG) &&
  	    (TAILQ_EMPTY(&asoc->resetHead)) &&
  	    (chunk_flags & SCTP_DATA_UNORDERED) == 0 &&
  	    SCTP_SSN_GE(asoc->strmin[strmno].last_sequence_delivered, strmseq)) {
  		/* The incoming sseq is behind where we last delivered? */
  		SCTPDBG(SCTP_DEBUG_INDATA1, "EVIL/Broken-Dup S-SEQ:%d delivered:%d from peer, Abort!\n",
  			strmseq, asoc->strmin[strmno].last_sequence_delivered);
  
  		snprintf(msg, sizeof(msg), "Delivered SSN=%4.4x, got TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  		         asoc->strmin[strmno].last_sequence_delivered,
  		         tsn, strmno, strmseq);
  		op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  		stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_16;
  		sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  		*abort_flag = 1;
  		return (0);
  	}
  	/************************************
  	 * From here down we may find ch-> invalid
  	 * so its a good idea NOT to use it.
  	 *************************************/
  
  	the_len = (chk_length - sizeof(struct sctp_data_chunk));
  	if (last_chunk == 0) {
  		dmbuf = SCTP_M_COPYM(*m,
  				     (offset + sizeof(struct sctp_data_chunk)),
  				     the_len, M_NOWAIT);
  #ifdef SCTP_MBUF_LOGGING
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MBUF_LOGGING_ENABLE) {
  			sctp_log_mbc(dmbuf, SCTP_MBUF_ICOPY);
  		}
  #endif
  	} else {
  		/* We can steal the last chunk */
  		int l_len;
  		dmbuf = *m;
  		/* lop off the top part */
  		m_adj(dmbuf, (offset + sizeof(struct sctp_data_chunk)));
  		if (SCTP_BUF_NEXT(dmbuf) == NULL) {
  			l_len = SCTP_BUF_LEN(dmbuf);
  		} else {
  			/* need to count up the size hopefully
  			 * does not hit this to often :-0
  			 */
  			struct mbuf *lat;
  
  			l_len = 0;
  			for (lat = dmbuf; lat; lat = SCTP_BUF_NEXT(lat)) {
  				l_len += SCTP_BUF_LEN(lat);
  			}
  		}
  		if (l_len > the_len) {
  			/* Trim the end round bytes off  too */
  			m_adj(dmbuf, -(l_len - the_len));
  		}
  	}
  	if (dmbuf == NULL) {
  		SCTP_STAT_INCR(sctps_nomem);
  		return (0);
  	}
  	if ((chunk_flags & SCTP_DATA_NOT_FRAG) == SCTP_DATA_NOT_FRAG &&
  	    asoc->fragmented_delivery_inprogress == 0 &&
  	    TAILQ_EMPTY(&asoc->resetHead) &&
  	    ((ordered == 0) ||
  	    ((uint16_t)(asoc->strmin[strmno].last_sequence_delivered + 1) == strmseq &&
  	    TAILQ_EMPTY(&asoc->strmin[strmno].inqueue)))) {
  		/* Candidate for express delivery */
  		/*
  		 * Its not fragmented, No PD-API is up, Nothing in the
  		 * delivery queue, Its un-ordered OR ordered and the next to
  		 * deliver AND nothing else is stuck on the stream queue,
  		 * And there is room for it in the socket buffer. Lets just
  		 * stuff it up the buffer....
  		 */
  
  		/* It would be nice to avoid this copy if we could :< */
  		sctp_alloc_a_readq(stcb, control);
  		sctp_build_readq_entry_mac(control, stcb, asoc->context, net, tsn,
  					   protocol_id,
  					   strmno, strmseq,
  					   chunk_flags,
  					   dmbuf);
  		if (control == NULL) {
  			goto failed_express_del;
  		}
  		SCTP_SET_TSN_PRESENT(asoc->nr_mapping_array, gap);
  		if (SCTP_TSN_GT(tsn, asoc->highest_tsn_inside_nr_map)) {
  			asoc->highest_tsn_inside_nr_map = tsn;
  		}
  		sctp_add_to_readq(stcb->sctp_ep, stcb,
  		                  control, &stcb->sctp_socket->so_rcv,
  		                  1, SCTP_READ_LOCK_NOT_HELD, SCTP_SO_NOT_LOCKED);
  
  		if ((chunk_flags & SCTP_DATA_UNORDERED) == 0) {
  			/* for ordered, bump what we delivered */
  			asoc->strmin[strmno].last_sequence_delivered++;
  		}
  		SCTP_STAT_INCR(sctps_recvexpress);
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_STR_LOGGING_ENABLE) {
  			sctp_log_strm_del_alt(stcb, tsn, strmseq, strmno,
  					      SCTP_STR_LOG_FROM_EXPRS_DEL);
  		}
  		control = NULL;
  
  		goto finish_express_del;
  	}
  failed_express_del:
  	/* If we reach here this is a new chunk */
  	chk = NULL;
  	control = NULL;
  	/* Express for fragmented delivery? */
  	if ((asoc->fragmented_delivery_inprogress) &&
  	    (stcb->asoc.control_pdapi) &&
  	    (asoc->str_of_pdapi == strmno) &&
  	    (asoc->ssn_of_pdapi == strmseq)
  		) {
  		control = stcb->asoc.control_pdapi;
  		if ((chunk_flags & SCTP_DATA_FIRST_FRAG) == SCTP_DATA_FIRST_FRAG) {
  			/* Can't be another first? */
  			goto failed_pdapi_express_del;
  		}
  		if (tsn == (control->sinfo_tsn + 1)) {
  			/* Yep, we can add it on */
  			int end = 0;
  
  			if (chunk_flags & SCTP_DATA_LAST_FRAG) {
  				end = 1;
  			}
  			if (sctp_append_to_readq(stcb->sctp_ep, stcb, control, dmbuf, end,
  			                         tsn,
  			                         &stcb->sctp_socket->so_rcv)) {
  				SCTP_PRINTF("Append fails end:%d\n", end);
  				goto failed_pdapi_express_del;
  			}
  
  			SCTP_SET_TSN_PRESENT(asoc->nr_mapping_array, gap);
  			if (SCTP_TSN_GT(tsn, asoc->highest_tsn_inside_nr_map)) {
  				asoc->highest_tsn_inside_nr_map = tsn;
  			}
  			SCTP_STAT_INCR(sctps_recvexpressm);
  			asoc->tsn_last_delivered = tsn;
  			asoc->fragment_flags = chunk_flags;
  			asoc->tsn_of_pdapi_last_delivered = tsn;
  			asoc->last_flags_delivered = chunk_flags;
  			asoc->last_strm_seq_delivered = strmseq;
  			asoc->last_strm_no_delivered = strmno;
  			if (end) {
  				/* clean up the flags and such */
  				asoc->fragmented_delivery_inprogress = 0;
  				if ((chunk_flags & SCTP_DATA_UNORDERED) == 0) {
  					asoc->strmin[strmno].last_sequence_delivered++;
  				}
  				stcb->asoc.control_pdapi = NULL;
  				if (TAILQ_EMPTY(&asoc->reasmqueue) == 0) {
  					/* There could be another message ready */
  					need_reasm_check = 1;
  				}
  			}
  			control = NULL;
  			goto finish_express_del;
  		}
  	}
   failed_pdapi_express_del:
  	control = NULL;
  	if (SCTP_BASE_SYSCTL(sctp_do_drain) == 0) {
  		SCTP_SET_TSN_PRESENT(asoc->nr_mapping_array, gap);
  		if (SCTP_TSN_GT(tsn, asoc->highest_tsn_inside_nr_map)) {
  			asoc->highest_tsn_inside_nr_map = tsn;
  		}
  	} else {
  		SCTP_SET_TSN_PRESENT(asoc->mapping_array, gap);
  		if (SCTP_TSN_GT(tsn, asoc->highest_tsn_inside_map)) {
  			asoc->highest_tsn_inside_map = tsn;
  		}
  	}
  	if ((chunk_flags & SCTP_DATA_NOT_FRAG) != SCTP_DATA_NOT_FRAG) {
  		sctp_alloc_a_chunk(stcb, chk);
  		if (chk == NULL) {
  			/* No memory so we drop the chunk */
  			SCTP_STAT_INCR(sctps_nomem);
  			if (last_chunk == 0) {
  				/* we copied it, free the copy */
  				sctp_m_freem(dmbuf);
  			}
  			return (0);
  		}
  		chk->rec.data.TSN_seq = tsn;
  		chk->no_fr_allowed = 0;
  		chk->rec.data.stream_seq = strmseq;
  		chk->rec.data.stream_number = strmno;
  		chk->rec.data.payloadtype = protocol_id;
  		chk->rec.data.context = stcb->asoc.context;
  		chk->rec.data.doing_fast_retransmit = 0;
  		chk->rec.data.rcv_flags = chunk_flags;
  		chk->asoc = asoc;
  		chk->send_size = the_len;
  		chk->whoTo = net;
  		atomic_add_int(&net->ref_count, 1);
  		chk->data = dmbuf;
  	} else {
  		sctp_alloc_a_readq(stcb, control);
  		sctp_build_readq_entry_mac(control, stcb, asoc->context, net, tsn,
  		    protocol_id,
  		    strmno, strmseq,
  		    chunk_flags,
  		    dmbuf);
  		if (control == NULL) {
  			/* No memory so we drop the chunk */
  			SCTP_STAT_INCR(sctps_nomem);
  			if (last_chunk == 0) {
  				/* we copied it, free the copy */
  				sctp_m_freem(dmbuf);
  			}
  			return (0);
  		}
  		control->length = the_len;
  	}
  
  	/* Mark it as received */
  	/* Now queue it where it belongs */
  	if (control != NULL) {
  		/* First a sanity check */
  		if (asoc->fragmented_delivery_inprogress) {
  			/*
  			 * Ok, we have a fragmented delivery in progress if
  			 * this chunk is next to deliver OR belongs in our
  			 * view to the reassembly, the peer is evil or
  			 * broken.
  			 */
  			uint32_t estimate_tsn;
  
  			estimate_tsn = asoc->tsn_last_delivered + 1;
  			if (TAILQ_EMPTY(&asoc->reasmqueue) &&
  			    (estimate_tsn == control->sinfo_tsn)) {
  				/* Evil/Broke peer */
  				sctp_m_freem(control->data);
  				control->data = NULL;
  				if (control->whoFrom) {
  					sctp_free_remote_addr(control->whoFrom);
  					control->whoFrom = NULL;
  				}
  				sctp_free_a_readq(stcb, control);
  				snprintf(msg, sizeof(msg), "Reas. queue emtpy, got TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  				         tsn, strmno, strmseq);
  				op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  				stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_17;
  				sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  				*abort_flag = 1;
  				if (last_chunk) {
  					*m = NULL;
  				}
  				return (0);
  			} else {
  				if (sctp_does_tsn_belong_to_reasm(asoc, control->sinfo_tsn)) {
  					sctp_m_freem(control->data);
  					control->data = NULL;
  					if (control->whoFrom) {
  						sctp_free_remote_addr(control->whoFrom);
  						control->whoFrom = NULL;
  					}
  					sctp_free_a_readq(stcb, control);
  					snprintf(msg, sizeof(msg), "PD ongoing, got TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  					         tsn, strmno, strmseq);
  					op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_18;
  					sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  					*abort_flag = 1;
  					if (last_chunk) {
  						*m = NULL;
  					}
  					return (0);
  				}
  			}
  		} else {
  			/* No PDAPI running */
  			if (!TAILQ_EMPTY(&asoc->reasmqueue)) {
  				/*
  				 * Reassembly queue is NOT empty validate
  				 * that this tsn does not need to be in
  				 * reasembly queue. If it does then our peer
  				 * is broken or evil.
  				 */
  				if (sctp_does_tsn_belong_to_reasm(asoc, control->sinfo_tsn)) {
  					sctp_m_freem(control->data);
  					control->data = NULL;
  					if (control->whoFrom) {
  						sctp_free_remote_addr(control->whoFrom);
  						control->whoFrom = NULL;
  					}
  					sctp_free_a_readq(stcb, control);
  					snprintf(msg, sizeof(msg), "No PD ongoing, got TSN=%8.8x, SID=%4.4x, SSN=%4.4x",
  					         tsn, strmno, strmseq);
  					op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_19;
  					sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  					*abort_flag = 1;
  					if (last_chunk) {
  						*m = NULL;
  					}
  					return (0);
  				}
  			}
  		}
  		/* ok, if we reach here we have passed the sanity checks */
  		if (chunk_flags & SCTP_DATA_UNORDERED) {
  			/* queue directly into socket buffer */
  			sctp_mark_non_revokable(asoc, control->sinfo_tsn);
  			sctp_add_to_readq(stcb->sctp_ep, stcb,
  			                  control,
  			                  &stcb->sctp_socket->so_rcv, 1, SCTP_READ_LOCK_NOT_HELD, SCTP_SO_NOT_LOCKED);
  		} else {
  			/*
  			 * Special check for when streams are resetting. We
  			 * could be more smart about this and check the
  			 * actual stream to see if it is not being reset..
  			 * that way we would not create a HOLB when amongst
  			 * streams being reset and those not being reset.
  			 *
  			 * We take complete messages that have a stream reset
  			 * intervening (aka the TSN is after where our
  			 * cum-ack needs to be) off and put them on a
  			 * pending_reply_queue. The reassembly ones we do
  			 * not have to worry about since they are all sorted
  			 * and proceessed by TSN order. It is only the
  			 * singletons I must worry about.
  			 */
  			if (((liste = TAILQ_FIRST(&asoc->resetHead)) != NULL) &&
  			    SCTP_TSN_GT(tsn, liste->tsn)) {
  				/*
  				 * yep its past where we need to reset... go
  				 * ahead and queue it.
  				 */
  				if (TAILQ_EMPTY(&asoc->pending_reply_queue)) {
  					/* first one on */
  					TAILQ_INSERT_TAIL(&asoc->pending_reply_queue, control, next);
  				} else {
  					struct sctp_queued_to_read *ctlOn, *nctlOn;
  					unsigned char inserted = 0;
  
  					TAILQ_FOREACH_SAFE(ctlOn, &asoc->pending_reply_queue, next, nctlOn) {
  						if (SCTP_TSN_GT(control->sinfo_tsn, ctlOn->sinfo_tsn)) {
  							continue;
  						} else {
  							/* found it */
  							TAILQ_INSERT_BEFORE(ctlOn, control, next);
  							inserted = 1;
  							break;
  						}
  					}
  					if (inserted == 0) {
  						/*
  						 * must be put at end, use
  						 * prevP (all setup from
  						 * loop) to setup nextP.
  						 */
  						TAILQ_INSERT_TAIL(&asoc->pending_reply_queue, control, next);
  					}
  				}
  			} else {
  				sctp_queue_data_to_stream(stcb, asoc, control, abort_flag);
  				if (*abort_flag) {
  					if (last_chunk) {
  						*m = NULL;
  					}
  					return (0);
  				}
  			}
  		}
  	} else {
  		/* Into the re-assembly queue */
  		sctp_queue_data_for_reasm(stcb, asoc, chk, abort_flag);
  		if (*abort_flag) {
  			/*
  			 * the assoc is now gone and chk was put onto the
  			 * reasm queue, which has all been freed.
  			 */
  			if (last_chunk) {
  				*m = NULL;
  			}
  			return (0);
  		}
  	}
  finish_express_del:
  	if (tsn == (asoc->cumulative_tsn + 1)) {
  		/* Update cum-ack */
  		asoc->cumulative_tsn = tsn;
  	}
  	if (last_chunk) {
  		*m = NULL;
  	}
  	if (ordered) {
  		SCTP_STAT_INCR_COUNTER64(sctps_inorderchunks);
  	} else {
  		SCTP_STAT_INCR_COUNTER64(sctps_inunorderchunks);
  	}
  	SCTP_STAT_INCR(sctps_recvdata);
  	/* Set it present please */
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_STR_LOGGING_ENABLE) {
  		sctp_log_strm_del_alt(stcb, tsn, strmseq, strmno, SCTP_STR_LOG_FROM_MARK_TSN);
  	}
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MAP_LOGGING_ENABLE) {
  		sctp_log_map(asoc->mapping_array_base_tsn, asoc->cumulative_tsn,
  			     asoc->highest_tsn_inside_map, SCTP_MAP_PREPARE_SLIDE);
  	}
  	/* check the special flag for stream resets */
  	if (((liste = TAILQ_FIRST(&asoc->resetHead)) != NULL) &&
  	    SCTP_TSN_GE(asoc->cumulative_tsn, liste->tsn)) {
  		/*
  		 * we have finished working through the backlogged TSN's now
  		 * time to reset streams. 1: call reset function. 2: free
  		 * pending_reply space 3: distribute any chunks in
  		 * pending_reply_queue.
  		 */
  		struct sctp_queued_to_read *ctl, *nctl;
  
  		sctp_reset_in_stream(stcb, liste->number_entries, liste->list_of_streams);
  		TAILQ_REMOVE(&asoc->resetHead, liste, next_resp);
  		SCTP_FREE(liste, SCTP_M_STRESET);
  		/*sa_ignore FREED_MEMORY*/
  		liste = TAILQ_FIRST(&asoc->resetHead);
  		if (TAILQ_EMPTY(&asoc->resetHead)) {
  			/* All can be removed */
  			TAILQ_FOREACH_SAFE(ctl, &asoc->pending_reply_queue, next, nctl) {
  				TAILQ_REMOVE(&asoc->pending_reply_queue, ctl, next);
  				sctp_queue_data_to_stream(stcb, asoc, ctl, abort_flag);
  				if (*abort_flag) {
  					return (0);
  				}
  			}
  		} else {
  			TAILQ_FOREACH_SAFE(ctl, &asoc->pending_reply_queue, next, nctl) {
  				if (SCTP_TSN_GT(ctl->sinfo_tsn, liste->tsn)) {
  					break;
  				}
  				/*
  				 * if ctl->sinfo_tsn is <= liste->tsn we can
  				 * process it which is the NOT of
  				 * ctl->sinfo_tsn > liste->tsn
  				 */
  				TAILQ_REMOVE(&asoc->pending_reply_queue, ctl, next);
  				sctp_queue_data_to_stream(stcb, asoc, ctl, abort_flag);
  				if (*abort_flag) {
  					return (0);
  				}
  			}
  		}
  		/*
  		 * Now service re-assembly to pick up anything that has been
  		 * held on reassembly queue?
  		 */
  		sctp_deliver_reasm_check(stcb, asoc);
  		need_reasm_check = 0;
  	}
  
  	if (need_reasm_check) {
  		/* Another one waits ? */
  		sctp_deliver_reasm_check(stcb, asoc);
  	}
  	return (1);
  }
  
  int8_t sctp_map_lookup_tab[256] = {
    0, 1, 0, 2, 0, 1, 0, 3,
    0, 1, 0, 2, 0, 1, 0, 4,
    0, 1, 0, 2, 0, 1, 0, 3,
    0, 1, 0, 2, 0, 1, 0, 5,
    0, 1, 0, 2, 0, 1, 0, 3,
    0, 1, 0, 2, 0, 1, 0, 4,
    0, 1, 0, 2, 0, 1, 0, 3,
    0, 1, 0, 2, 0, 1, 0, 6,
    0, 1, 0, 2, 0, 1, 0, 3,
    0, 1, 0, 2, 0, 1, 0, 4,
    0, 1, 0, 2, 0, 1, 0, 3,
    0, 1, 0, 2, 0, 1, 0, 5,
    0, 1, 0, 2, 0, 1, 0, 3,
    0, 1, 0, 2, 0, 1, 0, 4,
    0, 1, 0, 2, 0, 1, 0, 3,
    0, 1, 0, 2, 0, 1, 0, 7,
    0, 1, 0, 2, 0, 1, 0, 3,
    0, 1, 0, 2, 0, 1, 0, 4,
    0, 1, 0, 2, 0, 1, 0, 3,
    0, 1, 0, 2, 0, 1, 0, 5,
    0, 1, 0, 2, 0, 1, 0, 3,
    0, 1, 0, 2, 0, 1, 0, 4,
    0, 1, 0, 2, 0, 1, 0, 3,
    0, 1, 0, 2, 0, 1, 0, 6,
    0, 1, 0, 2, 0, 1, 0, 3,
    0, 1, 0, 2, 0, 1, 0, 4,
    0, 1, 0, 2, 0, 1, 0, 3,
    0, 1, 0, 2, 0, 1, 0, 5,
    0, 1, 0, 2, 0, 1, 0, 3,
    0, 1, 0, 2, 0, 1, 0, 4,
    0, 1, 0, 2, 0, 1, 0, 3,
    0, 1, 0, 2, 0, 1, 0, 8
  };
  
  
  void
  sctp_slide_mapping_arrays(struct sctp_tcb *stcb)
  {
  	/*
  	 * Now we also need to check the mapping array in a couple of ways.
  	 * 1) Did we move the cum-ack point?
  	 *
  	 * When you first glance at this you might think
  	 * that all entries that make up the postion
  	 * of the cum-ack would be in the nr-mapping array
  	 * only.. i.e. things up to the cum-ack are always
  	 * deliverable. Thats true with one exception, when
  	 * its a fragmented message we may not deliver the data
  	 * until some threshold (or all of it) is in place. So
  	 * we must OR the nr_mapping_array and mapping_array to
  	 * get a true picture of the cum-ack.
  	 */
  	struct sctp_association *asoc;
  	int at;
  	uint8_t val;
  	int slide_from, slide_end, lgap, distance;
  	uint32_t old_cumack, old_base, old_highest, highest_tsn;
  
  	asoc = &stcb->asoc;
  
  	old_cumack = asoc->cumulative_tsn;
  	old_base = asoc->mapping_array_base_tsn;
  	old_highest = asoc->highest_tsn_inside_map;
  	/*
  	 * We could probably improve this a small bit by calculating the
  	 * offset of the current cum-ack as the starting point.
  	 */
  	at = 0;
  	for (slide_from = 0; slide_from < stcb->asoc.mapping_array_size; slide_from++) {
  		val = asoc->nr_mapping_array[slide_from] | asoc->mapping_array[slide_from];
  		if (val == 0xff) {
  			at += 8;
  		} else {
  			/* there is a 0 bit */
  			at += sctp_map_lookup_tab[val];
  			break;
  		}
  	}
  	asoc->cumulative_tsn = asoc->mapping_array_base_tsn + (at-1);
  
  	if (SCTP_TSN_GT(asoc->cumulative_tsn, asoc->highest_tsn_inside_map) &&
              SCTP_TSN_GT(asoc->cumulative_tsn, asoc->highest_tsn_inside_nr_map)) {
  #ifdef INVARIANTS
  		panic("huh, cumack 0x%x greater than high-tsn 0x%x in map",
  		      asoc->cumulative_tsn, asoc->highest_tsn_inside_map);
  #else
  		SCTP_PRINTF("huh, cumack 0x%x greater than high-tsn 0x%x in map - should panic?\n",
  			    asoc->cumulative_tsn, asoc->highest_tsn_inside_map);
  		sctp_print_mapping_array(asoc);
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MAP_LOGGING_ENABLE) {
  			sctp_log_map(0, 6, asoc->highest_tsn_inside_map, SCTP_MAP_SLIDE_RESULT);
  		}
  		asoc->highest_tsn_inside_map = asoc->cumulative_tsn;
  		asoc->highest_tsn_inside_nr_map = asoc->cumulative_tsn;
  #endif
  	}
  	if (SCTP_TSN_GT(asoc->highest_tsn_inside_nr_map, asoc->highest_tsn_inside_map)) {
  		highest_tsn = asoc->highest_tsn_inside_nr_map;
  	} else {
  		highest_tsn = asoc->highest_tsn_inside_map;
  	}
  	if ((asoc->cumulative_tsn == highest_tsn) && (at >= 8)) {
  		/* The complete array was completed by a single FR */
  		/* highest becomes the cum-ack */
  		int clr;
  #ifdef INVARIANTS
  		unsigned int i;
  #endif
  
  		/* clear the array */
  		clr = ((at+7) >> 3);
  		if (clr > asoc->mapping_array_size) {
  			clr = asoc->mapping_array_size;
  		}
  		memset(asoc->mapping_array, 0, clr);
  		memset(asoc->nr_mapping_array, 0, clr);
  #ifdef INVARIANTS
  		for (i = 0; i < asoc->mapping_array_size; i++) {
  			if ((asoc->mapping_array[i]) || (asoc->nr_mapping_array[i])) {
  				SCTP_PRINTF("Error Mapping array's not clean at clear\n");
  				sctp_print_mapping_array(asoc);
  			}
  		}
  #endif
  		asoc->mapping_array_base_tsn = asoc->cumulative_tsn + 1;
  		asoc->highest_tsn_inside_nr_map = asoc->highest_tsn_inside_map = asoc->cumulative_tsn;
  	} else if (at >= 8) {
  		/* we can slide the mapping array down */
  		/* slide_from holds where we hit the first NON 0xff byte */
  
  		/*
  		 * now calculate the ceiling of the move using our highest
  		 * TSN value
  		 */
  		SCTP_CALC_TSN_TO_GAP(lgap, highest_tsn, asoc->mapping_array_base_tsn);
  		slide_end = (lgap >> 3);
  		if (slide_end < slide_from) {
  			sctp_print_mapping_array(asoc);
  #ifdef INVARIANTS
  			panic("impossible slide");
  #else
  			SCTP_PRINTF("impossible slide lgap:%x slide_end:%x slide_from:%x? at:%d\n",
  			            lgap, slide_end, slide_from, at);
  			return;
  #endif
  		}
  		if (slide_end > asoc->mapping_array_size) {
  #ifdef INVARIANTS
  			panic("would overrun buffer");
  #else
  			SCTP_PRINTF("Gak, would have overrun map end:%d slide_end:%d\n",
  			            asoc->mapping_array_size, slide_end);
  			slide_end = asoc->mapping_array_size;
  #endif
  		}
  		distance = (slide_end - slide_from) + 1;
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MAP_LOGGING_ENABLE) {
  			sctp_log_map(old_base, old_cumack, old_highest,
  				     SCTP_MAP_PREPARE_SLIDE);
  			sctp_log_map((uint32_t) slide_from, (uint32_t) slide_end,
  				     (uint32_t) lgap, SCTP_MAP_SLIDE_FROM);
  		}
  		if (distance + slide_from > asoc->mapping_array_size ||
  		    distance < 0) {
  			/*
  			 * Here we do NOT slide forward the array so that
  			 * hopefully when more data comes in to fill it up
  			 * we will be able to slide it forward. Really I
  			 * don't think this should happen :-0
  			 */
  
  			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MAP_LOGGING_ENABLE) {
  				sctp_log_map((uint32_t) distance, (uint32_t) slide_from,
  					     (uint32_t) asoc->mapping_array_size,
  					     SCTP_MAP_SLIDE_NONE);
  			}
  		} else {
  			int ii;
  
  			for (ii = 0; ii < distance; ii++) {
  				asoc->mapping_array[ii] = asoc->mapping_array[slide_from + ii];
  				asoc->nr_mapping_array[ii] = asoc->nr_mapping_array[slide_from + ii];
  
  			}
  			for (ii = distance; ii < asoc->mapping_array_size; ii++) {
  				asoc->mapping_array[ii] = 0;
  				asoc->nr_mapping_array[ii] = 0;
  			}
  			if (asoc->highest_tsn_inside_map + 1 == asoc->mapping_array_base_tsn) {
  				asoc->highest_tsn_inside_map += (slide_from << 3);
  			}
  			if (asoc->highest_tsn_inside_nr_map + 1 == asoc->mapping_array_base_tsn) {
  				asoc->highest_tsn_inside_nr_map += (slide_from << 3);
  			}
  			asoc->mapping_array_base_tsn += (slide_from << 3);
  			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MAP_LOGGING_ENABLE) {
  				sctp_log_map(asoc->mapping_array_base_tsn,
  					     asoc->cumulative_tsn, asoc->highest_tsn_inside_map,
  					     SCTP_MAP_SLIDE_RESULT);
  			}
  		}
  	}
  }
  
  void
  sctp_sack_check(struct sctp_tcb *stcb, int was_a_gap)
  {
  	struct sctp_association *asoc;
  	uint32_t highest_tsn;
  
  	asoc = &stcb->asoc;
  	if (SCTP_TSN_GT(asoc->highest_tsn_inside_nr_map, asoc->highest_tsn_inside_map)) {
  		highest_tsn = asoc->highest_tsn_inside_nr_map;
  	} else {
  		highest_tsn = asoc->highest_tsn_inside_map;
  	}
  
  	/*
  	 * Now we need to see if we need to queue a sack or just start the
  	 * timer (if allowed).
  	 */
  	if (SCTP_GET_STATE(asoc) == SCTP_STATE_SHUTDOWN_SENT) {
  		/*
  		 * Ok special case, in SHUTDOWN-SENT case. here we
  		 * maker sure SACK timer is off and instead send a
  		 * SHUTDOWN and a SACK
  		 */
  		if (SCTP_OS_TIMER_PENDING(&stcb->asoc.dack_timer.timer)) {
  			sctp_timer_stop(SCTP_TIMER_TYPE_RECV,
  			                stcb->sctp_ep, stcb, NULL,
  			                SCTP_FROM_SCTP_INDATA + SCTP_LOC_20);
  		}
  		sctp_send_shutdown(stcb,
  				   ((stcb->asoc.alternate) ? stcb->asoc.alternate : stcb->asoc.primary_destination));
  		sctp_send_sack(stcb, SCTP_SO_NOT_LOCKED);
  	} else {
  		int is_a_gap;
  
  		/* is there a gap now ? */
  		is_a_gap = SCTP_TSN_GT(highest_tsn, stcb->asoc.cumulative_tsn);
  
  		/*
  		 * CMT DAC algorithm: increase number of packets
  		 * received since last ack
  		 */
  		stcb->asoc.cmt_dac_pkts_rcvd++;
  
  		if ((stcb->asoc.send_sack == 1) ||      /* We need to send a SACK */
  		    ((was_a_gap) && (is_a_gap == 0)) ||	/* was a gap, but no
  		                                         * longer is one */
  		    (stcb->asoc.numduptsns) ||          /* we have dup's */
  		    (is_a_gap) ||                       /* is still a gap */
  		    (stcb->asoc.delayed_ack == 0) ||    /* Delayed sack disabled */
  		    (stcb->asoc.data_pkts_seen >= stcb->asoc.sack_freq)	/* hit limit of pkts */
  			) {
  
  			if ((stcb->asoc.sctp_cmt_on_off > 0) &&
  			    (SCTP_BASE_SYSCTL(sctp_cmt_use_dac)) &&
  			    (stcb->asoc.send_sack == 0) &&
  			    (stcb->asoc.numduptsns == 0) &&
  			    (stcb->asoc.delayed_ack) &&
  			    (!SCTP_OS_TIMER_PENDING(&stcb->asoc.dack_timer.timer))) {
  
  				/*
  				 * CMT DAC algorithm: With CMT,
  				 * delay acks even in the face of
  
  				 * reordering. Therefore, if acks
  				 * that do not have to be sent
  				 * because of the above reasons,
  				 * will be delayed. That is, acks
  				 * that would have been sent due to
  				 * gap reports will be delayed with
  				 * DAC. Start the delayed ack timer.
  				 */
  				sctp_timer_start(SCTP_TIMER_TYPE_RECV,
  				                 stcb->sctp_ep, stcb, NULL);
  			} else {
  				/*
  				 * Ok we must build a SACK since the
  				 * timer is pending, we got our
  				 * first packet OR there are gaps or
  				 * duplicates.
  				 */
  				(void)SCTP_OS_TIMER_STOP(&stcb->asoc.dack_timer.timer);
  				sctp_send_sack(stcb, SCTP_SO_NOT_LOCKED);
  			}
  		} else {
  			if (!SCTP_OS_TIMER_PENDING(&stcb->asoc.dack_timer.timer)) {
  				sctp_timer_start(SCTP_TIMER_TYPE_RECV,
  				                 stcb->sctp_ep, stcb, NULL);
  			}
  		}
  	}
  }
  
  void
  sctp_service_queues(struct sctp_tcb *stcb, struct sctp_association *asoc)
  {
  	struct sctp_tmit_chunk *chk;
  	uint32_t tsize, pd_point;
  	uint16_t nxt_todel;
  
  	if (asoc->fragmented_delivery_inprogress) {
  		sctp_service_reassembly(stcb, asoc);
  	}
  	/* Can we proceed further, i.e. the PD-API is complete */
  	if (asoc->fragmented_delivery_inprogress) {
  		/* no */
  		return;
  	}
  	/*
  	 * Now is there some other chunk I can deliver from the reassembly
  	 * queue.
  	 */
   doit_again:
  	chk = TAILQ_FIRST(&asoc->reasmqueue);
  	if (chk == NULL) {
  		asoc->size_on_reasm_queue = 0;
  		asoc->cnt_on_reasm_queue = 0;
  		return;
  	}
  	nxt_todel = asoc->strmin[chk->rec.data.stream_number].last_sequence_delivered + 1;
  	if ((chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) &&
  	    ((nxt_todel == chk->rec.data.stream_seq) ||
  	    (chk->rec.data.rcv_flags & SCTP_DATA_UNORDERED))) {
  		/*
  		 * Yep the first one is here. We setup to start reception,
  		 * by backing down the TSN just in case we can't deliver.
  		 */
  
  		/*
  		 * Before we start though either all of the message should
  		 * be here or the socket buffer max or nothing on the
  		 * delivery queue and something can be delivered.
  		 */
  		if (stcb->sctp_socket) {
  			pd_point = min(SCTP_SB_LIMIT_RCV(stcb->sctp_socket) >> SCTP_PARTIAL_DELIVERY_SHIFT,
  				       stcb->sctp_ep->partial_delivery_point);
  		} else {
  			pd_point = stcb->sctp_ep->partial_delivery_point;
  		}
  		if (sctp_is_all_msg_on_reasm(asoc, &tsize) || (tsize >= pd_point)) {
  			asoc->fragmented_delivery_inprogress = 1;
  			asoc->tsn_last_delivered = chk->rec.data.TSN_seq - 1;
  			asoc->str_of_pdapi = chk->rec.data.stream_number;
  			asoc->ssn_of_pdapi = chk->rec.data.stream_seq;
  			asoc->pdapi_ppid = chk->rec.data.payloadtype;
  			asoc->fragment_flags = chk->rec.data.rcv_flags;
  			sctp_service_reassembly(stcb, asoc);
  			if (asoc->fragmented_delivery_inprogress == 0) {
  				goto doit_again;
  			}
  		}
  	}
  }
  
  int
  sctp_process_data(struct mbuf **mm, int iphlen, int *offset, int length,
                    struct sockaddr *src, struct sockaddr *dst,
                    struct sctphdr *sh, struct sctp_inpcb *inp,
                    struct sctp_tcb *stcb, struct sctp_nets *net, uint32_t *high_tsn,
  #if defined(__FreeBSD__)
                    uint8_t mflowtype, uint32_t mflowid,
  #endif
  		  uint32_t vrf_id, uint16_t port)
  {
  	struct sctp_data_chunk *ch, chunk_buf;
  	struct sctp_association *asoc;
  	int num_chunks = 0;	/* number of control chunks processed */
  	int stop_proc = 0;
  	int chk_length, break_flag, last_chunk;
  	int abort_flag = 0, was_a_gap;
  	struct mbuf *m;
  	uint32_t highest_tsn;
  
  	/* set the rwnd */
  	sctp_set_rwnd(stcb, &stcb->asoc);
  
  	m = *mm;
  	SCTP_TCB_LOCK_ASSERT(stcb);
  	asoc = &stcb->asoc;
  	if (SCTP_TSN_GT(asoc->highest_tsn_inside_nr_map, asoc->highest_tsn_inside_map)) {
  		highest_tsn = asoc->highest_tsn_inside_nr_map;
  	} else {
  		highest_tsn = asoc->highest_tsn_inside_map;
  	}
  	was_a_gap = SCTP_TSN_GT(highest_tsn, stcb->asoc.cumulative_tsn);
  	/*
  	 * setup where we got the last DATA packet from for any SACK that
  	 * may need to go out. Don't bump the net. This is done ONLY when a
  	 * chunk is assigned.
  	 */
  	asoc->last_data_chunk_from = net;
  
  #ifndef __Panda__
  	/*-
  	 * Now before we proceed we must figure out if this is a wasted
  	 * cluster... i.e. it is a small packet sent in and yet the driver
  	 * underneath allocated a full cluster for it. If so we must copy it
  	 * to a smaller mbuf and free up the cluster mbuf. This will help
  	 * with cluster starvation. Note for __Panda__ we don't do this
  	 * since it has clusters all the way down to 64 bytes.
  	 */
  	if (SCTP_BUF_LEN(m) < (long)MLEN && SCTP_BUF_NEXT(m) == NULL) {
  		/* we only handle mbufs that are singletons.. not chains */
  		m = sctp_get_mbuf_for_msg(SCTP_BUF_LEN(m), 0, M_NOWAIT, 1, MT_DATA);
  		if (m) {
  			/* ok lets see if we can copy the data up */
  			caddr_t *from, *to;
  			/* get the pointers and copy */
  			to = mtod(m, caddr_t *);
  			from = mtod((*mm), caddr_t *);
  			memcpy(to, from, SCTP_BUF_LEN((*mm)));
  			/* copy the length and free up the old */
  			SCTP_BUF_LEN(m) = SCTP_BUF_LEN((*mm));
  			sctp_m_freem(*mm);
  			/* sucess, back copy */
  			*mm = m;
  		} else {
  			/* We are in trouble in the mbuf world .. yikes */
  			m = *mm;
  		}
  	}
  #endif
  	/* get pointer to the first chunk header */
  	ch = (struct sctp_data_chunk *)sctp_m_getptr(m, *offset,
  						     sizeof(struct sctp_data_chunk), (uint8_t *) & chunk_buf);
  	if (ch == NULL) {
  		return (1);
  	}
  	/*
  	 * process all DATA chunks...
  	 */
  	*high_tsn = asoc->cumulative_tsn;
  	break_flag = 0;
  	asoc->data_pkts_seen++;
  	while (stop_proc == 0) {
  		/* validate chunk length */
  		chk_length = ntohs(ch->ch.chunk_length);
  		if (length - *offset < chk_length) {
  			/* all done, mutulated chunk */
  			stop_proc = 1;
  			continue;
  		}
  		if (ch->ch.chunk_type == SCTP_DATA) {
  			if ((size_t)chk_length < sizeof(struct sctp_data_chunk)) {
  				/*
  				 * Need to send an abort since we had a
  				 * invalid data chunk.
  				 */
  				struct mbuf *op_err;
  				char msg[SCTP_DIAG_INFO_LEN];
  
  				snprintf(msg, sizeof(msg), "DATA chunk of length %d",
  				         chk_length);
  				op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  				stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_21;
  				sctp_abort_association(inp, stcb, m, iphlen,
  				                       src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  				                       mflowtype, mflowid,
  #endif
  				                       vrf_id, port);
  				return (2);
  			}
  			if ((size_t)chk_length == sizeof(struct sctp_data_chunk)) {
  				/*
  				 * Need to send an abort since we had an
  				 * empty data chunk.
  				 */
  				struct mbuf *op_err;
  
  				op_err = sctp_generate_no_user_data_cause(ch->dp.tsn);
  				stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_22;
  				sctp_abort_association(inp, stcb, m, iphlen,
  				                       src, dst, sh, op_err,
  #if defined(__FreeBSD__)
  				                       mflowtype, mflowid,
  #endif
  				                       vrf_id, port);
  				return (2);
  			}
  #ifdef SCTP_AUDITING_ENABLED
  			sctp_audit_log(0xB1, 0);
  #endif
  			if (SCTP_SIZE32(chk_length) == (length - *offset)) {
  				last_chunk = 1;
  			} else {
  				last_chunk = 0;
  			}
  			if (sctp_process_a_data_chunk(stcb, asoc, mm, *offset, ch,
  						      chk_length, net, high_tsn, &abort_flag, &break_flag,
  						      last_chunk)) {
  				num_chunks++;
  			}
  			if (abort_flag)
  				return (2);
  
  			if (break_flag) {
  				/*
  				 * Set because of out of rwnd space and no
  				 * drop rep space left.
  				 */
  				stop_proc = 1;
  				continue;
  			}
  		} else {
  			/* not a data chunk in the data region */
  			switch (ch->ch.chunk_type) {
  			case SCTP_INITIATION:
  			case SCTP_INITIATION_ACK:
  			case SCTP_SELECTIVE_ACK:
  			case SCTP_NR_SELECTIVE_ACK:
  			case SCTP_HEARTBEAT_REQUEST:
  			case SCTP_HEARTBEAT_ACK:
  			case SCTP_ABORT_ASSOCIATION:
  			case SCTP_SHUTDOWN:
  			case SCTP_SHUTDOWN_ACK:
  			case SCTP_OPERATION_ERROR:
  			case SCTP_COOKIE_ECHO:
  			case SCTP_COOKIE_ACK:
  			case SCTP_ECN_ECHO:
  			case SCTP_ECN_CWR:
  			case SCTP_SHUTDOWN_COMPLETE:
  			case SCTP_AUTHENTICATION:
  			case SCTP_ASCONF_ACK:
  			case SCTP_PACKET_DROPPED:
  			case SCTP_STREAM_RESET:
  			case SCTP_FORWARD_CUM_TSN:
  			case SCTP_ASCONF:
  				/*
  				 * Now, what do we do with KNOWN chunks that
  				 * are NOT in the right place?
  				 *
  				 * For now, I do nothing but ignore them. We
  				 * may later want to add sysctl stuff to
  				 * switch out and do either an ABORT() or
  				 * possibly process them.
  				 */
  				if (SCTP_BASE_SYSCTL(sctp_strict_data_order)) {
  					struct mbuf *op_err;
  
  					op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, "");
  					sctp_abort_association(inp, stcb,
  					                       m, iphlen,
  					                       src, dst,
  					                       sh, op_err,
  #if defined(__FreeBSD__)
  					                       mflowtype, mflowid,
  #endif
  					                       vrf_id, port);
  					return (2);
  				}
  				break;
  			default:
  				/* unknown chunk type, use bit rules */
  				if (ch->ch.chunk_type & 0x40) {
  					/* Add a error report to the queue */
  					struct mbuf *merr;
  					struct sctp_paramhdr *phd;
  
  					merr = sctp_get_mbuf_for_msg(sizeof(*phd), 0, M_NOWAIT, 1, MT_DATA);
  					if (merr) {
  						phd = mtod(merr, struct sctp_paramhdr *);
  						/*
  						 * We cheat and use param
  						 * type since we did not
  						 * bother to define a error
  						 * cause struct. They are
  						 * the same basic format
  						 * with different names.
  						 */
  						phd->param_type =
  							htons(SCTP_CAUSE_UNRECOG_CHUNK);
  						phd->param_length =
  							htons(chk_length + sizeof(*phd));
  						SCTP_BUF_LEN(merr) = sizeof(*phd);
  						SCTP_BUF_NEXT(merr) = SCTP_M_COPYM(m, *offset, chk_length, M_NOWAIT);
  						if (SCTP_BUF_NEXT(merr)) {
  							if (sctp_pad_lastmbuf(SCTP_BUF_NEXT(merr), SCTP_SIZE32(chk_length) - chk_length, NULL) == NULL) {
  								sctp_m_freem(merr);
  							} else {
  								sctp_queue_op_err(stcb, merr);
  							}
  						} else {
  							sctp_m_freem(merr);
  						}
  					}
  				}
  				if ((ch->ch.chunk_type & 0x80) == 0) {
  					/* discard the rest of this packet */
  					stop_proc = 1;
  				}	/* else skip this bad chunk and
  					 * continue... */
  				break;
  			}	/* switch of chunk type */
  		}
  		*offset += SCTP_SIZE32(chk_length);
  		if ((*offset >= length) || stop_proc) {
  			/* no more data left in the mbuf chain */
  			stop_proc = 1;
  			continue;
  		}
  		ch = (struct sctp_data_chunk *)sctp_m_getptr(m, *offset,
  							     sizeof(struct sctp_data_chunk), (uint8_t *) & chunk_buf);
  		if (ch == NULL) {
  			*offset = length;
  			stop_proc = 1;
  			continue;
  		}
  	}
  	if (break_flag) {
  		/*
  		 * we need to report rwnd overrun drops.
  		 */
  		sctp_send_packet_dropped(stcb, net, *mm, length, iphlen, 0);
  	}
  	if (num_chunks) {
  		/*
  		 * Did we get data, if so update the time for auto-close and
  		 * give peer credit for being alive.
  		 */
  		SCTP_STAT_INCR(sctps_recvpktwithdata);
  		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_INDATA,
  				       __LINE__);
  		}
  		stcb->asoc.overall_error_count = 0;
  		(void)SCTP_GETTIME_TIMEVAL(&stcb->asoc.time_last_rcvd);
  	}
  	/* now service all of the reassm queue if needed */
  	if (!(TAILQ_EMPTY(&asoc->reasmqueue)))
  		sctp_service_queues(stcb, asoc);
  
  	if (SCTP_GET_STATE(asoc) == SCTP_STATE_SHUTDOWN_SENT) {
  		/* Assure that we ack right away */
  		stcb->asoc.send_sack = 1;
  	}
  	/* Start a sack timer or QUEUE a SACK for sending */
  	sctp_sack_check(stcb, was_a_gap);
  	return (0);
  }
  
  static int
  sctp_process_segment_range(struct sctp_tcb *stcb, struct sctp_tmit_chunk **p_tp1, uint32_t last_tsn,
  			   uint16_t frag_strt, uint16_t frag_end, int nr_sacking,
  			   int *num_frs,
  			   uint32_t *biggest_newly_acked_tsn,
  			   uint32_t  *this_sack_lowest_newack,
  			   int *rto_ok)
  {
  	struct sctp_tmit_chunk *tp1;
  	unsigned int theTSN;
  	int j, wake_him = 0, circled = 0;
  
  	/* Recover the tp1 we last saw */
  	tp1 = *p_tp1;
  	if (tp1 == NULL) {
  		tp1 = TAILQ_FIRST(&stcb->asoc.sent_queue);
  	}
  	for (j = frag_strt; j <= frag_end; j++) {
  		theTSN = j + last_tsn;
  		while (tp1) {
  			if (tp1->rec.data.doing_fast_retransmit)
  				(*num_frs) += 1;
  
  			/*-
  			 * CMT: CUCv2 algorithm. For each TSN being
  			 * processed from the sent queue, track the
  			 * next expected pseudo-cumack, or
  			 * rtx_pseudo_cumack, if required. Separate
  			 * cumack trackers for first transmissions,
  			 * and retransmissions.
  			 */
  			if ((tp1->sent < SCTP_DATAGRAM_RESEND) &&
  			    (tp1->whoTo->find_pseudo_cumack == 1) &&
  			    (tp1->snd_count == 1)) {
  				tp1->whoTo->pseudo_cumack = tp1->rec.data.TSN_seq;
  				tp1->whoTo->find_pseudo_cumack = 0;
  			}
  			if ((tp1->sent < SCTP_DATAGRAM_RESEND) &&
  			    (tp1->whoTo->find_rtx_pseudo_cumack == 1) &&
  			    (tp1->snd_count > 1)) {
  				tp1->whoTo->rtx_pseudo_cumack = tp1->rec.data.TSN_seq;
  				tp1->whoTo->find_rtx_pseudo_cumack = 0;
  			}
  			if (tp1->rec.data.TSN_seq == theTSN) {
  				if (tp1->sent != SCTP_DATAGRAM_UNSENT) {
  					/*-
  					 * must be held until
  					 * cum-ack passes
  					 */
  					if (tp1->sent < SCTP_DATAGRAM_RESEND) {
  						/*-
  						 * If it is less than RESEND, it is
  						 * now no-longer in flight.
  						 * Higher values may already be set
  						 * via previous Gap Ack Blocks...
  						 * i.e. ACKED or RESEND.
  						 */
  						if (SCTP_TSN_GT(tp1->rec.data.TSN_seq,
  						                *biggest_newly_acked_tsn)) {
  							*biggest_newly_acked_tsn = tp1->rec.data.TSN_seq;
  						}
  						/*-
  						 * CMT: SFR algo (and HTNA) - set
  						 * saw_newack to 1 for dest being
  						 * newly acked. update
  						 * this_sack_highest_newack if
  						 * appropriate.
  						 */
  						if (tp1->rec.data.chunk_was_revoked == 0)
  							tp1->whoTo->saw_newack = 1;
  
  						if (SCTP_TSN_GT(tp1->rec.data.TSN_seq,
  						                tp1->whoTo->this_sack_highest_newack)) {
  							tp1->whoTo->this_sack_highest_newack =
  								tp1->rec.data.TSN_seq;
  						}
  						/*-
  						 * CMT DAC algo: also update
  						 * this_sack_lowest_newack
  						 */
  						if (*this_sack_lowest_newack == 0) {
  							if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_SACK_LOGGING_ENABLE) {
  								sctp_log_sack(*this_sack_lowest_newack,
  									      last_tsn,
  									      tp1->rec.data.TSN_seq,
  									      0,
  									      0,
  									      SCTP_LOG_TSN_ACKED);
  							}
  							*this_sack_lowest_newack = tp1->rec.data.TSN_seq;
  						}
  						/*-
  						 * CMT: CUCv2 algorithm. If (rtx-)pseudo-cumack for corresp
  						 * dest is being acked, then we have a new (rtx-)pseudo-cumack. Set
  						 * new_(rtx_)pseudo_cumack to TRUE so that the cwnd for this dest can be
  						 * updated. Also trigger search for the next expected (rtx-)pseudo-cumack.
  						 * Separate pseudo_cumack trackers for first transmissions and
  						 * retransmissions.
  						 */
  						if (tp1->rec.data.TSN_seq == tp1->whoTo->pseudo_cumack) {
  							if (tp1->rec.data.chunk_was_revoked == 0) {
  								tp1->whoTo->new_pseudo_cumack = 1;
  							}
  							tp1->whoTo->find_pseudo_cumack = 1;
  						}
  						if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
  							sctp_log_cwnd(stcb, tp1->whoTo, tp1->rec.data.TSN_seq, SCTP_CWND_LOG_FROM_SACK);
  						}
  						if (tp1->rec.data.TSN_seq == tp1->whoTo->rtx_pseudo_cumack) {
  							if (tp1->rec.data.chunk_was_revoked == 0) {
  								tp1->whoTo->new_pseudo_cumack = 1;
  							}
  							tp1->whoTo->find_rtx_pseudo_cumack = 1;
  						}
  						if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_SACK_LOGGING_ENABLE) {
  							sctp_log_sack(*biggest_newly_acked_tsn,
  								      last_tsn,
  								      tp1->rec.data.TSN_seq,
  								      frag_strt,
  								      frag_end,
  								      SCTP_LOG_TSN_ACKED);
  						}
  						if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FLIGHT_LOGGING_ENABLE) {
  							sctp_misc_ints(SCTP_FLIGHT_LOG_DOWN_GAP,
  								       tp1->whoTo->flight_size,
  								       tp1->book_size,
  								       (uintptr_t)tp1->whoTo,
  								       tp1->rec.data.TSN_seq);
  						}
  						sctp_flight_size_decrease(tp1);
  						if (stcb->asoc.cc_functions.sctp_cwnd_update_tsn_acknowledged) {
  							(*stcb->asoc.cc_functions.sctp_cwnd_update_tsn_acknowledged)(tp1->whoTo,
  														     tp1);
  						}
  						sctp_total_flight_decrease(stcb, tp1);
  
  						tp1->whoTo->net_ack += tp1->send_size;
  						if (tp1->snd_count < 2) {
  							/*-
  							 * True non-retransmited chunk
  							 */
  							tp1->whoTo->net_ack2 += tp1->send_size;
  
  							/*-
  							 * update RTO too ?
  							 */
  							if (tp1->do_rtt) {
  								if (*rto_ok) {
  									tp1->whoTo->RTO =
  										sctp_calculate_rto(stcb,
  												   &stcb->asoc,
  												   tp1->whoTo,
  												   &tp1->sent_rcv_time,
  												   sctp_align_safe_nocopy,
  												   SCTP_RTT_FROM_DATA);
  									*rto_ok = 0;
  								}
  								if (tp1->whoTo->rto_needed == 0) {
  									tp1->whoTo->rto_needed = 1;
  								}
  								tp1->do_rtt = 0;
  							}
  						}
  
  					}
  					if (tp1->sent <= SCTP_DATAGRAM_RESEND) {
  						if (SCTP_TSN_GT(tp1->rec.data.TSN_seq,
  						                stcb->asoc.this_sack_highest_gap)) {
  							stcb->asoc.this_sack_highest_gap =
  								tp1->rec.data.TSN_seq;
  						}
  						if (tp1->sent == SCTP_DATAGRAM_RESEND) {
  							sctp_ucount_decr(stcb->asoc.sent_queue_retran_cnt);
  #ifdef SCTP_AUDITING_ENABLED
  							sctp_audit_log(0xB2,
  								       (stcb->asoc.sent_queue_retran_cnt & 0x000000ff));
  #endif
  						}
  					}
  					/*-
  					 * All chunks NOT UNSENT fall through here and are marked
  					 * (leave PR-SCTP ones that are to skip alone though)
  					 */
  					if ((tp1->sent != SCTP_FORWARD_TSN_SKIP) &&
  					    (tp1->sent != SCTP_DATAGRAM_NR_ACKED)) {
  						tp1->sent = SCTP_DATAGRAM_MARKED;
  					}
  					if (tp1->rec.data.chunk_was_revoked) {
  						/* deflate the cwnd */
  						tp1->whoTo->cwnd -= tp1->book_size;
  						tp1->rec.data.chunk_was_revoked = 0;
  					}
  					/* NR Sack code here */
  					if (nr_sacking &&
  					    (tp1->sent != SCTP_DATAGRAM_NR_ACKED)) {
  						if (stcb->asoc.strmout[tp1->rec.data.stream_number].chunks_on_queues > 0) {
  							stcb->asoc.strmout[tp1->rec.data.stream_number].chunks_on_queues--;
  #ifdef INVARIANTS
  						} else {
  							panic("No chunks on the queues for sid %u.", tp1->rec.data.stream_number);
  #endif
  						}
  						tp1->sent = SCTP_DATAGRAM_NR_ACKED;
  						if (tp1->data) {
  							/* sa_ignore NO_NULL_CHK */
  							sctp_free_bufspace(stcb, &stcb->asoc, tp1, 1);
  							sctp_m_freem(tp1->data);
  							tp1->data = NULL;
  						}
  						wake_him++;
  					}
  				}
  				break;
  			}	/* if (tp1->TSN_seq == theTSN) */
  			if (SCTP_TSN_GT(tp1->rec.data.TSN_seq, theTSN)) {
  				break;
  			}
  			tp1 = TAILQ_NEXT(tp1, sctp_next);
  			if ((tp1 == NULL) && (circled == 0)) {
  				circled++;
  				tp1 = TAILQ_FIRST(&stcb->asoc.sent_queue);
  			}
  		}	/* end while (tp1) */
  		if (tp1 == NULL) {
  			circled = 0;
  			tp1 = TAILQ_FIRST(&stcb->asoc.sent_queue);
  		}
  		/* In case the fragments were not in order we must reset */
  	} /* end for (j = fragStart */
  	*p_tp1 = tp1;
  	return (wake_him);	/* Return value only used for nr-sack */
  }
  
  
  static int
  sctp_handle_segments(struct mbuf *m, int *offset, struct sctp_tcb *stcb, struct sctp_association *asoc,
  		uint32_t last_tsn, uint32_t *biggest_tsn_acked,
  		uint32_t *biggest_newly_acked_tsn, uint32_t *this_sack_lowest_newack,
  		int num_seg, int num_nr_seg, int *rto_ok)
  {
  	struct sctp_gap_ack_block *frag, block;
  	struct sctp_tmit_chunk *tp1;
  	int i;
  	int num_frs = 0;
  	int chunk_freed;
  	int non_revocable;
  	uint16_t frag_strt, frag_end, prev_frag_end;
  
  	tp1 = TAILQ_FIRST(&asoc->sent_queue);
  	prev_frag_end = 0;
  	chunk_freed = 0;
  
  	for (i = 0; i < (num_seg + num_nr_seg); i++) {
  		if (i == num_seg) {
  			prev_frag_end = 0;
  			tp1 = TAILQ_FIRST(&asoc->sent_queue);
  		}
  		frag = (struct sctp_gap_ack_block *)sctp_m_getptr(m, *offset,
  		                                                  sizeof(struct sctp_gap_ack_block), (uint8_t *) &block);
  		*offset += sizeof(block);
  		if (frag == NULL) {
  			return (chunk_freed);
  		}
  		frag_strt = ntohs(frag->start);
  		frag_end = ntohs(frag->end);
  
  		if (frag_strt > frag_end) {
  			/* This gap report is malformed, skip it. */
  			continue;
  		}
  		if (frag_strt <= prev_frag_end) {
  			/* This gap report is not in order, so restart. */
  			 tp1 = TAILQ_FIRST(&asoc->sent_queue);
  		}
  		if (SCTP_TSN_GT((last_tsn + frag_end), *biggest_tsn_acked)) {
  			*biggest_tsn_acked = last_tsn + frag_end;
  		}
  		if (i < num_seg) {
  			non_revocable = 0;
  		} else {
  			non_revocable = 1;
  		}
  		if (sctp_process_segment_range(stcb, &tp1, last_tsn, frag_strt, frag_end,
  		                               non_revocable, &num_frs, biggest_newly_acked_tsn,
  		                               this_sack_lowest_newack, rto_ok)) {
  			chunk_freed = 1;
  		}
  		prev_frag_end = frag_end;
  	}
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
  		if (num_frs)
  			sctp_log_fr(*biggest_tsn_acked,
  			            *biggest_newly_acked_tsn,
  			            last_tsn, SCTP_FR_LOG_BIGGEST_TSNS);
  	}
  	return (chunk_freed);
  }
  
  static void
  sctp_check_for_revoked(struct sctp_tcb *stcb,
  		       struct sctp_association *asoc, uint32_t cumack,
  		       uint32_t biggest_tsn_acked)
  {
  	struct sctp_tmit_chunk *tp1;
  
  	TAILQ_FOREACH(tp1, &asoc->sent_queue, sctp_next) {
  		if (SCTP_TSN_GT(tp1->rec.data.TSN_seq, cumack)) {
  			/*
  			 * ok this guy is either ACK or MARKED. If it is
  			 * ACKED it has been previously acked but not this
  			 * time i.e. revoked.  If it is MARKED it was ACK'ed
  			 * again.
  			 */
  			if (SCTP_TSN_GT(tp1->rec.data.TSN_seq, biggest_tsn_acked)) {
  				break;
  			}
  			if (tp1->sent == SCTP_DATAGRAM_ACKED) {
  				/* it has been revoked */
  				tp1->sent = SCTP_DATAGRAM_SENT;
  				tp1->rec.data.chunk_was_revoked = 1;
  				/* We must add this stuff back in to
  				 * assure timers and such get started.
  				 */
  				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FLIGHT_LOGGING_ENABLE) {
  					sctp_misc_ints(SCTP_FLIGHT_LOG_UP_REVOKE,
  						       tp1->whoTo->flight_size,
  						       tp1->book_size,
  						       (uintptr_t)tp1->whoTo,
  						       tp1->rec.data.TSN_seq);
  				}
  				sctp_flight_size_increase(tp1);
  				sctp_total_flight_increase(stcb, tp1);
  				/* We inflate the cwnd to compensate for our
  				 * artificial inflation of the flight_size.
  				 */
  				tp1->whoTo->cwnd += tp1->book_size;
  				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_SACK_LOGGING_ENABLE) {
  					sctp_log_sack(asoc->last_acked_seq,
  						      cumack,
  						      tp1->rec.data.TSN_seq,
  						      0,
  						      0,
  						      SCTP_LOG_TSN_REVOKED);
  				}
  			} else if (tp1->sent == SCTP_DATAGRAM_MARKED) {
  				/* it has been re-acked in this SACK */
  				tp1->sent = SCTP_DATAGRAM_ACKED;
  			}
  		}
  		if (tp1->sent == SCTP_DATAGRAM_UNSENT)
  			break;
  	}
  }
  
  
  static void
  sctp_strike_gap_ack_chunks(struct sctp_tcb *stcb, struct sctp_association *asoc,
  			   uint32_t biggest_tsn_acked, uint32_t biggest_tsn_newly_acked, uint32_t this_sack_lowest_newack, int accum_moved)
  {
  	struct sctp_tmit_chunk *tp1;
  	int strike_flag = 0;
  	struct timeval now;
  	int tot_retrans = 0;
  	uint32_t sending_seq;
  	struct sctp_nets *net;
  	int num_dests_sacked = 0;
  
  	/*
  	 * select the sending_seq, this is either the next thing ready to be
  	 * sent but not transmitted, OR, the next seq we assign.
  	 */
  	tp1 = TAILQ_FIRST(&stcb->asoc.send_queue);
  	if (tp1 == NULL) {
  		sending_seq = asoc->sending_seq;
  	} else {
  		sending_seq = tp1->rec.data.TSN_seq;
  	}
  
  	/* CMT DAC algo: finding out if SACK is a mixed SACK */
  	if ((asoc->sctp_cmt_on_off > 0) &&
  	    SCTP_BASE_SYSCTL(sctp_cmt_use_dac)) {
  		TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  			if (net->saw_newack)
  				num_dests_sacked++;
  		}
  	}
  	if (stcb->asoc.prsctp_supported) {
  		(void)SCTP_GETTIME_TIMEVAL(&now);
  	}
  	TAILQ_FOREACH(tp1, &asoc->sent_queue, sctp_next) {
  		strike_flag = 0;
  		if (tp1->no_fr_allowed) {
  			/* this one had a timeout or something */
  			continue;
  		}
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
  			if (tp1->sent < SCTP_DATAGRAM_RESEND)
  				sctp_log_fr(biggest_tsn_newly_acked,
  					    tp1->rec.data.TSN_seq,
  					    tp1->sent,
  					    SCTP_FR_LOG_CHECK_STRIKE);
  		}
  		if (SCTP_TSN_GT(tp1->rec.data.TSN_seq, biggest_tsn_acked) ||
  		    tp1->sent == SCTP_DATAGRAM_UNSENT) {
  			/* done */
  			break;
  		}
  		if (stcb->asoc.prsctp_supported) {
  			if ((PR_SCTP_TTL_ENABLED(tp1->flags)) && tp1->sent < SCTP_DATAGRAM_ACKED) {
  				/* Is it expired? */
  #ifndef __FreeBSD__
  				if (timercmp(&now, &tp1->rec.data.timetodrop, >)) {
  #else
  				if (timevalcmp(&now, &tp1->rec.data.timetodrop, >)) {
  #endif
  					/* Yes so drop it */
  					if (tp1->data != NULL) {
  						(void)sctp_release_pr_sctp_chunk(stcb, tp1, 1,
  										 SCTP_SO_NOT_LOCKED);
  					}
  					continue;
  				}
  			}
  
  		}
  		if (SCTP_TSN_GT(tp1->rec.data.TSN_seq, asoc->this_sack_highest_gap)) {
  			/* we are beyond the tsn in the sack  */
  			break;
  		}
  		if (tp1->sent >= SCTP_DATAGRAM_RESEND) {
  			/* either a RESEND, ACKED, or MARKED */
  			/* skip */
  			if (tp1->sent == SCTP_FORWARD_TSN_SKIP) {
  				/* Continue strikin FWD-TSN chunks */
  				tp1->rec.data.fwd_tsn_cnt++;
  			}
  			continue;
  		}
  		/*
  		 * CMT : SFR algo (covers part of DAC and HTNA as well)
  		 */
  		if (tp1->whoTo && tp1->whoTo->saw_newack == 0) {
  			/*
  			 * No new acks were receieved for data sent to this
  			 * dest. Therefore, according to the SFR algo for
  			 * CMT, no data sent to this dest can be marked for
  			 * FR using this SACK.
  			 */
  			continue;
  		} else if (tp1->whoTo && SCTP_TSN_GT(tp1->rec.data.TSN_seq,
  		                                     tp1->whoTo->this_sack_highest_newack)) {
  			/*
  			 * CMT: New acks were receieved for data sent to
  			 * this dest. But no new acks were seen for data
  			 * sent after tp1. Therefore, according to the SFR
  			 * algo for CMT, tp1 cannot be marked for FR using
  			 * this SACK. This step covers part of the DAC algo
  			 * and the HTNA algo as well.
  			 */
  			continue;
  		}
  		/*
  		 * Here we check to see if we were have already done a FR
  		 * and if so we see if the biggest TSN we saw in the sack is
  		 * smaller than the recovery point. If so we don't strike
  		 * the tsn... otherwise we CAN strike the TSN.
  		 */
  		/*
  		 * @@@ JRI: Check for CMT
  		 * if (accum_moved && asoc->fast_retran_loss_recovery && (sctp_cmt_on_off == 0)) {
  		 */
  		if (accum_moved && asoc->fast_retran_loss_recovery) {
  			/*
  			 * Strike the TSN if in fast-recovery and cum-ack
  			 * moved.
  			 */
  			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
  				sctp_log_fr(biggest_tsn_newly_acked,
  					    tp1->rec.data.TSN_seq,
  					    tp1->sent,
  					    SCTP_FR_LOG_STRIKE_CHUNK);
  			}
  			if (tp1->sent < SCTP_DATAGRAM_RESEND) {
  				tp1->sent++;
  			}
  			if ((asoc->sctp_cmt_on_off > 0) &&
  			    SCTP_BASE_SYSCTL(sctp_cmt_use_dac)) {
  				/*
  				 * CMT DAC algorithm: If SACK flag is set to
  				 * 0, then lowest_newack test will not pass
  				 * because it would have been set to the
  				 * cumack earlier. If not already to be
  				 * rtx'd, If not a mixed sack and if tp1 is
  				 * not between two sacked TSNs, then mark by
  				 * one more.
  				 * NOTE that we are marking by one additional time since the SACK DAC flag indicates that
  				 * two packets have been received after this missing TSN.
  				 */
  				if ((tp1->sent < SCTP_DATAGRAM_RESEND) && (num_dests_sacked == 1) &&
  				    SCTP_TSN_GT(this_sack_lowest_newack, tp1->rec.data.TSN_seq)) {
  					if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
  						sctp_log_fr(16 + num_dests_sacked,
  							    tp1->rec.data.TSN_seq,
  							    tp1->sent,
  							    SCTP_FR_LOG_STRIKE_CHUNK);
  					}
  					tp1->sent++;
  				}
  			}
  		} else if ((tp1->rec.data.doing_fast_retransmit) &&
  		           (asoc->sctp_cmt_on_off == 0)) {
  			/*
  			 * For those that have done a FR we must take
  			 * special consideration if we strike. I.e the
  			 * biggest_newly_acked must be higher than the
  			 * sending_seq at the time we did the FR.
  			 */
  			if (
  #ifdef SCTP_FR_TO_ALTERNATE
  				/*
  				 * If FR's go to new networks, then we must only do
  				 * this for singly homed asoc's. However if the FR's
  				 * go to the same network (Armando's work) then its
  				 * ok to FR multiple times.
  				 */
  				(asoc->numnets < 2)
  #else
  				(1)
  #endif
  				) {
  
  				if (SCTP_TSN_GE(biggest_tsn_newly_acked,
  				                tp1->rec.data.fast_retran_tsn)) {
  					/*
  					 * Strike the TSN, since this ack is
  					 * beyond where things were when we
  					 * did a FR.
  					 */
  					if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
  						sctp_log_fr(biggest_tsn_newly_acked,
  							    tp1->rec.data.TSN_seq,
  							    tp1->sent,
  							    SCTP_FR_LOG_STRIKE_CHUNK);
  					}
  					if (tp1->sent < SCTP_DATAGRAM_RESEND) {
  						tp1->sent++;
  					}
  					strike_flag = 1;
  					if ((asoc->sctp_cmt_on_off > 0) &&
  					    SCTP_BASE_SYSCTL(sctp_cmt_use_dac)) {
  						/*
  						 * CMT DAC algorithm: If
  						 * SACK flag is set to 0,
  						 * then lowest_newack test
  						 * will not pass because it
  						 * would have been set to
  						 * the cumack earlier. If
  						 * not already to be rtx'd,
  						 * If not a mixed sack and
  						 * if tp1 is not between two
  						 * sacked TSNs, then mark by
  						 * one more.
  						 * NOTE that we are marking by one additional time since the SACK DAC flag indicates that
  						 * two packets have been received after this missing TSN.
  						 */
  						if ((tp1->sent < SCTP_DATAGRAM_RESEND) &&
  						    (num_dests_sacked == 1) &&
  						    SCTP_TSN_GT(this_sack_lowest_newack,
  						                tp1->rec.data.TSN_seq)) {
  							if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
  								sctp_log_fr(32 + num_dests_sacked,
  									    tp1->rec.data.TSN_seq,
  									    tp1->sent,
  									    SCTP_FR_LOG_STRIKE_CHUNK);
  							}
  							if (tp1->sent < SCTP_DATAGRAM_RESEND) {
  								tp1->sent++;
  							}
  						}
  					}
  				}
  			}
  			/*
  			 * JRI: TODO: remove code for HTNA algo. CMT's
  			 * SFR algo covers HTNA.
  			 */
  		} else if (SCTP_TSN_GT(tp1->rec.data.TSN_seq,
  		                       biggest_tsn_newly_acked)) {
  			/*
  			 * We don't strike these: This is the  HTNA
  			 * algorithm i.e. we don't strike If our TSN is
  			 * larger than the Highest TSN Newly Acked.
  			 */
  			;
  		} else {
  			/* Strike the TSN */
  			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
  				sctp_log_fr(biggest_tsn_newly_acked,
  					    tp1->rec.data.TSN_seq,
  					    tp1->sent,
  					    SCTP_FR_LOG_STRIKE_CHUNK);
  			}
  			if (tp1->sent < SCTP_DATAGRAM_RESEND) {
  				tp1->sent++;
  			}
  			if ((asoc->sctp_cmt_on_off > 0) &&
  			    SCTP_BASE_SYSCTL(sctp_cmt_use_dac)) {
  				/*
  				 * CMT DAC algorithm: If SACK flag is set to
  				 * 0, then lowest_newack test will not pass
  				 * because it would have been set to the
  				 * cumack earlier. If not already to be
  				 * rtx'd, If not a mixed sack and if tp1 is
  				 * not between two sacked TSNs, then mark by
  				 * one more.
  				 * NOTE that we are marking by one additional time since the SACK DAC flag indicates that
  				 * two packets have been received after this missing TSN.
  				 */
  				if ((tp1->sent < SCTP_DATAGRAM_RESEND) && (num_dests_sacked == 1) &&
  				    SCTP_TSN_GT(this_sack_lowest_newack, tp1->rec.data.TSN_seq)) {
  					if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
  						sctp_log_fr(48 + num_dests_sacked,
  							    tp1->rec.data.TSN_seq,
  							    tp1->sent,
  							    SCTP_FR_LOG_STRIKE_CHUNK);
  					}
  					tp1->sent++;
  				}
  			}
  		}
  		if (tp1->sent == SCTP_DATAGRAM_RESEND) {
  			struct sctp_nets *alt;
  
  			/* fix counts and things */
  			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FLIGHT_LOGGING_ENABLE) {
  				sctp_misc_ints(SCTP_FLIGHT_LOG_DOWN_RSND,
  					       (tp1->whoTo ? (tp1->whoTo->flight_size) : 0),
  					       tp1->book_size,
  					       (uintptr_t)tp1->whoTo,
  					       tp1->rec.data.TSN_seq);
  			}
  			if (tp1->whoTo) {
  				tp1->whoTo->net_ack++;
  				sctp_flight_size_decrease(tp1);
  				if (stcb->asoc.cc_functions.sctp_cwnd_update_tsn_acknowledged) {
  					(*stcb->asoc.cc_functions.sctp_cwnd_update_tsn_acknowledged)(tp1->whoTo,
  												     tp1);
  				}
  			}
  
  			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LOG_RWND_ENABLE) {
  				sctp_log_rwnd(SCTP_INCREASE_PEER_RWND,
  					      asoc->peers_rwnd, tp1->send_size, SCTP_BASE_SYSCTL(sctp_peer_chunk_oh));
  			}
  			/* add back to the rwnd */
  			asoc->peers_rwnd += (tp1->send_size + SCTP_BASE_SYSCTL(sctp_peer_chunk_oh));
  
  			/* remove from the total flight */
  			sctp_total_flight_decrease(stcb, tp1);
  
  			if ((stcb->asoc.prsctp_supported) &&
  			    (PR_SCTP_RTX_ENABLED(tp1->flags))) {
  				/* Has it been retransmitted tv_sec times? - we store the retran count there. */
  				if (tp1->snd_count > tp1->rec.data.timetodrop.tv_sec) {
  					/* Yes, so drop it */
  					if (tp1->data != NULL) {
  						(void)sctp_release_pr_sctp_chunk(stcb, tp1, 1,
  										 SCTP_SO_NOT_LOCKED);
  					}
  					/* Make sure to flag we had a FR */
  					tp1->whoTo->net_ack++;
  					continue;
  				}
  			}
  			/* SCTP_PRINTF("OK, we are now ready to FR this guy\n"); */
  			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
  				sctp_log_fr(tp1->rec.data.TSN_seq, tp1->snd_count,
  					    0, SCTP_FR_MARKED);
  			}
  			if (strike_flag) {
  				/* This is a subsequent FR */
  				SCTP_STAT_INCR(sctps_sendmultfastretrans);
  			}
  			sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
  			if (asoc->sctp_cmt_on_off > 0) {
  				/*
  				 * CMT: Using RTX_SSTHRESH policy for CMT.
  				 * If CMT is being used, then pick dest with
  				 * largest ssthresh for any retransmission.
  				 */
  				tp1->no_fr_allowed = 1;
  				alt = tp1->whoTo;
  				/*sa_ignore NO_NULL_CHK*/
  				if (asoc->sctp_cmt_pf > 0) {
  					/* JRS 5/18/07 - If CMT PF is on, use the PF version of find_alt_net() */
  					alt = sctp_find_alternate_net(stcb, alt, 2);
  				} else {
  					/* JRS 5/18/07 - If only CMT is on, use the CMT version of find_alt_net() */
                                          /*sa_ignore NO_NULL_CHK*/
  					alt = sctp_find_alternate_net(stcb, alt, 1);
  				}
  				if (alt == NULL) {
  					alt = tp1->whoTo;
  				}
  				/*
  				 * CUCv2: If a different dest is picked for
  				 * the retransmission, then new
  				 * (rtx-)pseudo_cumack needs to be tracked
  				 * for orig dest. Let CUCv2 track new (rtx-)
  				 * pseudo-cumack always.
  				 */
  				if (tp1->whoTo) {
  					tp1->whoTo->find_pseudo_cumack = 1;
  					tp1->whoTo->find_rtx_pseudo_cumack = 1;
  				}
  
  			} else {/* CMT is OFF */
  
  #ifdef SCTP_FR_TO_ALTERNATE
  				/* Can we find an alternate? */
  				alt = sctp_find_alternate_net(stcb, tp1->whoTo, 0);
  #else
  				/*
  				 * default behavior is to NOT retransmit
  				 * FR's to an alternate. Armando Caro's
  				 * paper details why.
  				 */
  				alt = tp1->whoTo;
  #endif
  			}
  
  			tp1->rec.data.doing_fast_retransmit = 1;
  			tot_retrans++;
  			/* mark the sending seq for possible subsequent FR's */
  			/*
  			 * SCTP_PRINTF("Marking TSN for FR new value %x\n",
  			 * (uint32_t)tpi->rec.data.TSN_seq);
  			 */
  			if (TAILQ_EMPTY(&asoc->send_queue)) {
  				/*
  				 * If the queue of send is empty then its
  				 * the next sequence number that will be
  				 * assigned so we subtract one from this to
  				 * get the one we last sent.
  				 */
  				tp1->rec.data.fast_retran_tsn = sending_seq;
  			} else {
  				/*
  				 * If there are chunks on the send queue
  				 * (unsent data that has made it from the
  				 * stream queues but not out the door, we
  				 * take the first one (which will have the
  				 * lowest TSN) and subtract one to get the
  				 * one we last sent.
  				 */
  				struct sctp_tmit_chunk *ttt;
  
  				ttt = TAILQ_FIRST(&asoc->send_queue);
  				tp1->rec.data.fast_retran_tsn =
  					ttt->rec.data.TSN_seq;
  			}
  
  			if (tp1->do_rtt) {
  				/*
  				 * this guy had a RTO calculation pending on
  				 * it, cancel it
  				 */
  				if ((tp1->whoTo != NULL) &&
  				    (tp1->whoTo->rto_needed == 0)) {
  					tp1->whoTo->rto_needed = 1;
  				}
  				tp1->do_rtt = 0;
  			}
  			if (alt != tp1->whoTo) {
  				/* yes, there is an alternate. */
  				sctp_free_remote_addr(tp1->whoTo);
  				/*sa_ignore FREED_MEMORY*/
  				tp1->whoTo = alt;
  				atomic_add_int(&alt->ref_count, 1);
  			}
  		}
  	}
  }
  
  struct sctp_tmit_chunk *
  sctp_try_advance_peer_ack_point(struct sctp_tcb *stcb,
      struct sctp_association *asoc)
  {
  	struct sctp_tmit_chunk *tp1, *tp2, *a_adv = NULL;
  	struct timeval now;
  	int now_filled = 0;
  
  	if (asoc->prsctp_supported == 0) {
  		return (NULL);
  	}
  	TAILQ_FOREACH_SAFE(tp1, &asoc->sent_queue, sctp_next, tp2) {
  		if (tp1->sent != SCTP_FORWARD_TSN_SKIP &&
  		    tp1->sent != SCTP_DATAGRAM_RESEND &&
  		    tp1->sent != SCTP_DATAGRAM_NR_ACKED) {
  			/* no chance to advance, out of here */
  			break;
  		}
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LOG_TRY_ADVANCE) {
  			if ((tp1->sent == SCTP_FORWARD_TSN_SKIP) ||
  			    (tp1->sent == SCTP_DATAGRAM_NR_ACKED)) {
  				sctp_misc_ints(SCTP_FWD_TSN_CHECK,
  					       asoc->advanced_peer_ack_point,
  					       tp1->rec.data.TSN_seq, 0, 0);
  			}
  		}
  		if (!PR_SCTP_ENABLED(tp1->flags)) {
  			/*
  			 * We can't fwd-tsn past any that are reliable aka
  			 * retransmitted until the asoc fails.
  			 */
  			break;
  		}
  		if (!now_filled) {
  			(void)SCTP_GETTIME_TIMEVAL(&now);
  			now_filled = 1;
  		}
  		/*
  		 * now we got a chunk which is marked for another
  		 * retransmission to a PR-stream but has run out its chances
  		 * already maybe OR has been marked to skip now. Can we skip
  		 * it if its a resend?
  		 */
  		if (tp1->sent == SCTP_DATAGRAM_RESEND &&
  		    (PR_SCTP_TTL_ENABLED(tp1->flags))) {
  			/*
  			 * Now is this one marked for resend and its time is
  			 * now up?
  			 */
  #ifndef __FreeBSD__
  			if (timercmp(&now, &tp1->rec.data.timetodrop, >)) {
  #else
  			if (timevalcmp(&now, &tp1->rec.data.timetodrop, >)) {
  #endif
  				/* Yes so drop it */
  				if (tp1->data) {
  					(void)sctp_release_pr_sctp_chunk(stcb, tp1,
  					    1, SCTP_SO_NOT_LOCKED);
  				}
  			} else {
  				/*
  				 * No, we are done when hit one for resend
  				 * whos time as not expired.
  				 */
  				break;
  			}
  		}
  		/*
  		 * Ok now if this chunk is marked to drop it we can clean up
  		 * the chunk, advance our peer ack point and we can check
  		 * the next chunk.
  		 */
  		if ((tp1->sent == SCTP_FORWARD_TSN_SKIP) ||
  		    (tp1->sent == SCTP_DATAGRAM_NR_ACKED)) {
  			/* advance PeerAckPoint goes forward */
  			if (SCTP_TSN_GT(tp1->rec.data.TSN_seq, asoc->advanced_peer_ack_point)) {
  				asoc->advanced_peer_ack_point = tp1->rec.data.TSN_seq;
  				a_adv = tp1;
  			} else if (tp1->rec.data.TSN_seq == asoc->advanced_peer_ack_point) {
  				/* No update but we do save the chk */
  				a_adv = tp1;
  			}
  		} else {
  			/*
  			 * If it is still in RESEND we can advance no
  			 * further
  			 */
  			break;
  		}
  	}
  	return (a_adv);
  }
  
  static int
  sctp_fs_audit(struct sctp_association *asoc)
  {
  	struct sctp_tmit_chunk *chk;
  	int inflight = 0, resend = 0, inbetween = 0, acked = 0, above = 0;
  	int ret;
  #ifndef INVARIANTS
  	int entry_flight, entry_cnt;
  #endif
  
  	ret = 0;
  #ifndef INVARIANTS
  	entry_flight = asoc->total_flight;
  	entry_cnt = asoc->total_flight_count;
  #endif
  	if (asoc->pr_sctp_cnt >= asoc->sent_queue_cnt)
  		return (0);
  
  	TAILQ_FOREACH(chk, &asoc->sent_queue, sctp_next) {
  		if (chk->sent < SCTP_DATAGRAM_RESEND) {
  			SCTP_PRINTF("Chk TSN:%u size:%d inflight cnt:%d\n",
  			            chk->rec.data.TSN_seq,
  			            chk->send_size,
  			            chk->snd_count);
  			inflight++;
  		} else if (chk->sent == SCTP_DATAGRAM_RESEND) {
  			resend++;
  		} else if (chk->sent < SCTP_DATAGRAM_ACKED) {
  			inbetween++;
  		} else if (chk->sent > SCTP_DATAGRAM_ACKED) {
  			above++;
  		} else {
  			acked++;
  		}
  	}
  
  	if ((inflight > 0) || (inbetween > 0)) {
  #ifdef INVARIANTS
  		panic("Flight size-express incorrect? \n");
  #else
  		SCTP_PRINTF("asoc->total_flight:%d cnt:%d\n",
  		            entry_flight, entry_cnt);
  
  		SCTP_PRINTF("Flight size-express incorrect F:%d I:%d R:%d Ab:%d ACK:%d\n",
  			    inflight, inbetween, resend, above, acked);
  		ret = 1;
  #endif
  	}
  	return (ret);
  }
  
  
  static void
  sctp_window_probe_recovery(struct sctp_tcb *stcb,
  	                   struct sctp_association *asoc,
  			   struct sctp_tmit_chunk *tp1)
  {
  	tp1->window_probe = 0;
  	if ((tp1->sent >= SCTP_DATAGRAM_ACKED) || (tp1->data == NULL)) {
  		/* TSN's skipped we do NOT move back. */
  		sctp_misc_ints(SCTP_FLIGHT_LOG_DWN_WP_FWD,
  			       tp1->whoTo ? tp1->whoTo->flight_size : 0,
  			       tp1->book_size,
  			       (uintptr_t)tp1->whoTo,
  			       tp1->rec.data.TSN_seq);
  		return;
  	}
  	/* First setup this by shrinking flight */
  	if (stcb->asoc.cc_functions.sctp_cwnd_update_tsn_acknowledged) {
  		(*stcb->asoc.cc_functions.sctp_cwnd_update_tsn_acknowledged)(tp1->whoTo,
  									     tp1);
  	}
  	sctp_flight_size_decrease(tp1);
  	sctp_total_flight_decrease(stcb, tp1);
  	/* Now mark for resend */
  	tp1->sent = SCTP_DATAGRAM_RESEND;
  	sctp_ucount_incr(asoc->sent_queue_retran_cnt);
  
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FLIGHT_LOGGING_ENABLE) {
  		sctp_misc_ints(SCTP_FLIGHT_LOG_DOWN_WP,
  			       tp1->whoTo->flight_size,
  			       tp1->book_size,
  			       (uintptr_t)tp1->whoTo,
  			       tp1->rec.data.TSN_seq);
  	}
  }
  
  void
  sctp_express_handle_sack(struct sctp_tcb *stcb, uint32_t cumack,
                           uint32_t rwnd, int *abort_now, int ecne_seen)
  {
  	struct sctp_nets *net;
  	struct sctp_association *asoc;
  	struct sctp_tmit_chunk *tp1, *tp2;
  	uint32_t old_rwnd;
  	int win_probe_recovery = 0;
  	int win_probe_recovered = 0;
  	int j, done_once = 0;
  	int rto_ok = 1;
  
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LOG_SACK_ARRIVALS_ENABLE) {
  		sctp_misc_ints(SCTP_SACK_LOG_EXPRESS, cumack,
  		               rwnd, stcb->asoc.last_acked_seq, stcb->asoc.peers_rwnd);
  	}
  	SCTP_TCB_LOCK_ASSERT(stcb);
  #ifdef SCTP_ASOCLOG_OF_TSNS
  	stcb->asoc.cumack_log[stcb->asoc.cumack_log_at] = cumack;
  	stcb->asoc.cumack_log_at++;
  	if (stcb->asoc.cumack_log_at > SCTP_TSN_LOG_SIZE) {
  		stcb->asoc.cumack_log_at = 0;
  	}
  #endif
  	asoc = &stcb->asoc;
  	old_rwnd = asoc->peers_rwnd;
  	if (SCTP_TSN_GT(asoc->last_acked_seq, cumack)) {
  		/* old ack */
  		return;
  	} else if (asoc->last_acked_seq == cumack) {
  		/* Window update sack */
  		asoc->peers_rwnd = sctp_sbspace_sub(rwnd,
  						    (uint32_t) (asoc->total_flight + (asoc->total_flight_count * SCTP_BASE_SYSCTL(sctp_peer_chunk_oh))));
  		if (asoc->peers_rwnd < stcb->sctp_ep->sctp_ep.sctp_sws_sender) {
  			/* SWS sender side engages */
  			asoc->peers_rwnd = 0;
  		}
  		if (asoc->peers_rwnd > old_rwnd) {
  			goto again;
  		}
  		return;
  	}
  
  	/* First setup for CC stuff */
  	TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  		if (SCTP_TSN_GT(cumack, net->cwr_window_tsn)) {
  			/* Drag along the window_tsn for cwr's */
  			net->cwr_window_tsn = cumack;
  		}
  		net->prev_cwnd = net->cwnd;
  		net->net_ack = 0;
  		net->net_ack2 = 0;
  
  		/*
  		 * CMT: Reset CUC and Fast recovery algo variables before
  		 * SACK processing
  		 */
  		net->new_pseudo_cumack = 0;
  		net->will_exit_fast_recovery = 0;
  		if (stcb->asoc.cc_functions.sctp_cwnd_prepare_net_for_sack) {
  			(*stcb->asoc.cc_functions.sctp_cwnd_prepare_net_for_sack)(stcb, net);
  		}
  	}
  	if (SCTP_BASE_SYSCTL(sctp_strict_sacks)) {
  		uint32_t send_s;
  
  		if (!TAILQ_EMPTY(&asoc->sent_queue)) {
  			tp1 = TAILQ_LAST(&asoc->sent_queue,
  					 sctpchunk_listhead);
  			send_s = tp1->rec.data.TSN_seq + 1;
  		} else {
  			send_s = asoc->sending_seq;
  		}
  		if (SCTP_TSN_GE(cumack, send_s)) {
  			struct mbuf *op_err;
  			char msg[SCTP_DIAG_INFO_LEN];
  
  			*abort_now = 1;
  			/* XXX */
  			snprintf(msg, sizeof(msg), "Cum ack %8.8x greater or equal than TSN %8.8x",
  			         cumack, send_s);
  			op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  			stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_23;
  			sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  			return;
  		}
  	}
  	asoc->this_sack_highest_gap = cumack;
  	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_INDATA,
  			       __LINE__);
  	}
  	stcb->asoc.overall_error_count = 0;
  	if (SCTP_TSN_GT(cumack, asoc->last_acked_seq)) {
  		/* process the new consecutive TSN first */
  		TAILQ_FOREACH_SAFE(tp1, &asoc->sent_queue, sctp_next, tp2) {
  			if (SCTP_TSN_GE(cumack, tp1->rec.data.TSN_seq)) {
  				if (tp1->sent == SCTP_DATAGRAM_UNSENT) {
  					SCTP_PRINTF("Warning, an unsent is now acked?\n");
  				}
  				if (tp1->sent < SCTP_DATAGRAM_ACKED) {
  					/*
  					 * If it is less than ACKED, it is
  					 * now no-longer in flight. Higher
  					 * values may occur during marking
  					 */
  					if (tp1->sent < SCTP_DATAGRAM_RESEND) {
  						if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FLIGHT_LOGGING_ENABLE) {
  							sctp_misc_ints(SCTP_FLIGHT_LOG_DOWN_CA,
  								       tp1->whoTo->flight_size,
  								       tp1->book_size,
  								       (uintptr_t)tp1->whoTo,
  								       tp1->rec.data.TSN_seq);
  						}
  						sctp_flight_size_decrease(tp1);
  						if (stcb->asoc.cc_functions.sctp_cwnd_update_tsn_acknowledged) {
  							(*stcb->asoc.cc_functions.sctp_cwnd_update_tsn_acknowledged)(tp1->whoTo,
  														     tp1);
  						}
  						/* sa_ignore NO_NULL_CHK */
  						sctp_total_flight_decrease(stcb, tp1);
  					}
  					tp1->whoTo->net_ack += tp1->send_size;
  					if (tp1->snd_count < 2) {
  						/*
  						 * True non-retransmited
  						 * chunk
  						 */
  						tp1->whoTo->net_ack2 +=
  							tp1->send_size;
  
  						/* update RTO too? */
  						if (tp1->do_rtt) {
  							if (rto_ok) {
  								tp1->whoTo->RTO =
  									/*
  									 * sa_ignore
  									 * NO_NULL_CHK
  									 */
  									sctp_calculate_rto(stcb,
  											   asoc, tp1->whoTo,
  											   &tp1->sent_rcv_time,
  											   sctp_align_safe_nocopy,
  											   SCTP_RTT_FROM_DATA);
  								rto_ok = 0;
  							}
  							if (tp1->whoTo->rto_needed == 0) {
  								tp1->whoTo->rto_needed = 1;
  							}
  							tp1->do_rtt = 0;
  						}
  					}
  					/*
  					 * CMT: CUCv2 algorithm. From the
  					 * cumack'd TSNs, for each TSN being
  					 * acked for the first time, set the
  					 * following variables for the
  					 * corresp destination.
  					 * new_pseudo_cumack will trigger a
  					 * cwnd update.
  					 * find_(rtx_)pseudo_cumack will
  					 * trigger search for the next
  					 * expected (rtx-)pseudo-cumack.
  					 */
  					tp1->whoTo->new_pseudo_cumack = 1;
  					tp1->whoTo->find_pseudo_cumack = 1;
  					tp1->whoTo->find_rtx_pseudo_cumack = 1;
  
  					if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
  						/* sa_ignore NO_NULL_CHK */
  						sctp_log_cwnd(stcb, tp1->whoTo, tp1->rec.data.TSN_seq, SCTP_CWND_LOG_FROM_SACK);
  					}
  				}
  				if (tp1->sent == SCTP_DATAGRAM_RESEND) {
  					sctp_ucount_decr(asoc->sent_queue_retran_cnt);
  				}
  				if (tp1->rec.data.chunk_was_revoked) {
  					/* deflate the cwnd */
  					tp1->whoTo->cwnd -= tp1->book_size;
  					tp1->rec.data.chunk_was_revoked = 0;
  				}
  				if (tp1->sent != SCTP_DATAGRAM_NR_ACKED) {
  					if (asoc->strmout[tp1->rec.data.stream_number].chunks_on_queues > 0) {
  						asoc->strmout[tp1->rec.data.stream_number].chunks_on_queues--;
  #ifdef INVARIANTS
  					} else {
  						panic("No chunks on the queues for sid %u.", tp1->rec.data.stream_number);
  #endif
  					}
  				}
  				TAILQ_REMOVE(&asoc->sent_queue, tp1, sctp_next);
  				if (tp1->data) {
  					/* sa_ignore NO_NULL_CHK */
  					sctp_free_bufspace(stcb, asoc, tp1, 1);
  					sctp_m_freem(tp1->data);
  					tp1->data = NULL;
  				}
  				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_SACK_LOGGING_ENABLE) {
  					sctp_log_sack(asoc->last_acked_seq,
  						      cumack,
  						      tp1->rec.data.TSN_seq,
  						      0,
  						      0,
  						      SCTP_LOG_FREE_SENT);
  				}
  				asoc->sent_queue_cnt--;
  				sctp_free_a_chunk(stcb, tp1, SCTP_SO_NOT_LOCKED);
  			} else {
  				break;
  			}
  		}
  
  	}
  #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);
  			}
  		}
  	} else if (stcb->sctp_socket) {
  #else
  	/* sa_ignore NO_NULL_CHK */
  	if (stcb->sctp_socket) {
  #endif
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		struct socket *so;
  
  #endif
  		SOCKBUF_LOCK(&stcb->sctp_socket->so_snd);
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_WAKE_LOGGING_ENABLE) {
  			/* sa_ignore NO_NULL_CHK */
  			sctp_wakeup_log(stcb, 1, SCTP_WAKESND_FROM_SACK);
  		}
  #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
  		sctp_sowwakeup_locked(stcb->sctp_ep, stcb->sctp_socket);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  	} else {
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_WAKE_LOGGING_ENABLE) {
  			sctp_wakeup_log(stcb, 1, SCTP_NOWAKE_FROM_SACK);
  		}
  	}
  
  	/* JRS - Use the congestion control given in the CC module */
  	if ((asoc->last_acked_seq != cumack) && (ecne_seen == 0)) {
  		TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  			if (net->net_ack2 > 0) {
  				/*
  				 * Karn's rule applies to clearing error count, this
  				 * is optional.
  				 */
  				net->error_count = 0;
  				if (!(net->dest_state & SCTP_ADDR_REACHABLE)) {
  					/* addr came good */
  					net->dest_state |= SCTP_ADDR_REACHABLE;
  					sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_UP, stcb,
  					                0, (void *)net, SCTP_SO_NOT_LOCKED);
  				}
  				if (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;
  					}
  				}
  				if (net->dest_state & SCTP_ADDR_PF) {
  					net->dest_state &= ~SCTP_ADDR_PF;
  					sctp_timer_stop(SCTP_TIMER_TYPE_HEARTBEAT,
  					                stcb->sctp_ep, stcb, net,
  					                SCTP_FROM_SCTP_INDATA + SCTP_LOC_24);
  					sctp_timer_start(SCTP_TIMER_TYPE_HEARTBEAT, stcb->sctp_ep, stcb, net);
  					asoc->cc_functions.sctp_cwnd_update_exit_pf(stcb, net);
  					/* Done with this net */
  					net->net_ack = 0;
  				}
  				/* restore any doubled timers */
  				net->RTO = (net->lastsa >> SCTP_RTT_SHIFT) + net->lastsv;
  				if (net->RTO < stcb->asoc.minrto) {
  					net->RTO = stcb->asoc.minrto;
  				}
  				if (net->RTO > stcb->asoc.maxrto) {
  					net->RTO = stcb->asoc.maxrto;
  				}
  			}
  		}
  		asoc->cc_functions.sctp_cwnd_update_after_sack(stcb, asoc, 1, 0, 0);
  	}
  	asoc->last_acked_seq = cumack;
  
  	if (TAILQ_EMPTY(&asoc->sent_queue)) {
  		/* nothing left in-flight */
  		TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  			net->flight_size = 0;
  			net->partial_bytes_acked = 0;
  		}
  		asoc->total_flight = 0;
  		asoc->total_flight_count = 0;
  	}
  
  	/* RWND update */
  	asoc->peers_rwnd = sctp_sbspace_sub(rwnd,
  					    (uint32_t) (asoc->total_flight + (asoc->total_flight_count * SCTP_BASE_SYSCTL(sctp_peer_chunk_oh))));
  	if (asoc->peers_rwnd < stcb->sctp_ep->sctp_ep.sctp_sws_sender) {
  		/* SWS sender side engages */
  		asoc->peers_rwnd = 0;
  	}
  	if (asoc->peers_rwnd > old_rwnd) {
  		win_probe_recovery = 1;
  	}
  	/* Now assure a timer where data is queued at */
  again:
  	j = 0;
  	TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  		int to_ticks;
  		if (win_probe_recovery && (net->window_probe)) {
  			win_probe_recovered = 1;
  			/*
  			 * Find first chunk that was used with window probe
  			 * and clear the sent
  			 */
  			/* sa_ignore FREED_MEMORY */
  			TAILQ_FOREACH(tp1, &asoc->sent_queue, sctp_next) {
  				if (tp1->window_probe) {
  					/* move back to data send queue */
  					sctp_window_probe_recovery(stcb, asoc, tp1);
  					break;
  				}
  			}
  		}
  		if (net->RTO == 0) {
  			to_ticks = MSEC_TO_TICKS(stcb->asoc.initial_rto);
  		} else {
  			to_ticks = MSEC_TO_TICKS(net->RTO);
  		}
  		if (net->flight_size) {
  			j++;
  			(void)SCTP_OS_TIMER_START(&net->rxt_timer.timer, to_ticks,
  						  sctp_timeout_handler, &net->rxt_timer);
  			if (net->window_probe) {
  				net->window_probe = 0;
  			}
  		} else {
  			if (net->window_probe) {
  				/* In window probes we must assure a timer is still running there */
  				net->window_probe = 0;
  				if (!SCTP_OS_TIMER_PENDING(&net->rxt_timer.timer)) {
  					SCTP_OS_TIMER_START(&net->rxt_timer.timer, to_ticks,
  					                    sctp_timeout_handler, &net->rxt_timer);
  				}
  			} else if (SCTP_OS_TIMER_PENDING(&net->rxt_timer.timer)) {
  				sctp_timer_stop(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
  				                stcb, net,
  				                SCTP_FROM_SCTP_INDATA + SCTP_LOC_25);
  			}
  		}
  	}
  	if ((j == 0) &&
  	    (!TAILQ_EMPTY(&asoc->sent_queue)) &&
  	    (asoc->sent_queue_retran_cnt == 0) &&
  	    (win_probe_recovered == 0) &&
  	    (done_once == 0)) {
  		/* huh, this should not happen unless all packets
  		 * are PR-SCTP and marked to skip of course.
  		 */
  		if (sctp_fs_audit(asoc)) {
  			TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  				net->flight_size = 0;
  			}
  			asoc->total_flight = 0;
  			asoc->total_flight_count = 0;
  			asoc->sent_queue_retran_cnt = 0;
  			TAILQ_FOREACH(tp1, &asoc->sent_queue, sctp_next) {
  				if (tp1->sent < SCTP_DATAGRAM_RESEND) {
  					sctp_flight_size_increase(tp1);
  					sctp_total_flight_increase(stcb, tp1);
  				} else if (tp1->sent == SCTP_DATAGRAM_RESEND) {
  					sctp_ucount_incr(asoc->sent_queue_retran_cnt);
  				}
  			}
  		}
  		done_once = 1;
  		goto again;
  	}
  	/**********************************/
  	/* Now what about shutdown issues */
  	/**********************************/
  	if (TAILQ_EMPTY(&asoc->send_queue) && TAILQ_EMPTY(&asoc->sent_queue)) {
  		/* nothing left on sendqueue.. consider done */
  		/* clean up */
  		if ((asoc->stream_queue_cnt == 1) &&
  		    ((asoc->state & SCTP_STATE_SHUTDOWN_PENDING) ||
  		     (asoc->state & SCTP_STATE_SHUTDOWN_RECEIVED)) &&
  		    (asoc->locked_on_sending)
  			) {
  			struct sctp_stream_queue_pending *sp;
  			/* I may be in a state where we got
  			 * all across.. but cannot write more due
  			 * to a shutdown... we abort since the
  			 * user did not indicate EOR in this case. The
  			 * sp will be cleaned during free of the asoc.
  			 */
  			sp = TAILQ_LAST(&((asoc->locked_on_sending)->outqueue),
  					sctp_streamhead);
  			if ((sp) && (sp->length == 0)) {
  				/* Let cleanup code purge it */
  				if (sp->msg_is_complete) {
  					asoc->stream_queue_cnt--;
  				} else {
  					asoc->state |= SCTP_STATE_PARTIAL_MSG_LEFT;
  					asoc->locked_on_sending = NULL;
  					asoc->stream_queue_cnt--;
  				}
  			}
  		}
  		if ((asoc->state & SCTP_STATE_SHUTDOWN_PENDING) &&
  		    (asoc->stream_queue_cnt == 0)) {
  			if (asoc->state & SCTP_STATE_PARTIAL_MSG_LEFT) {
  				/* Need to abort here */
  				struct mbuf *op_err;
  
  			abort_out_now:
  				*abort_now = 1;
  				/* XXX */
  				op_err = sctp_generate_cause(SCTP_CAUSE_USER_INITIATED_ABT, "");
  				stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_26;
  				sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  			} else {
  				struct sctp_nets *netp;
  
  				if ((SCTP_GET_STATE(asoc) == SCTP_STATE_OPEN) ||
  				    (SCTP_GET_STATE(asoc) == SCTP_STATE_SHUTDOWN_RECEIVED)) {
  					SCTP_STAT_DECR_GAUGE32(sctps_currestab);
  				}
  				SCTP_SET_STATE(asoc, SCTP_STATE_SHUTDOWN_SENT);
  				SCTP_CLEAR_SUBSTATE(asoc, SCTP_STATE_SHUTDOWN_PENDING);
  				sctp_stop_timers_for_shutdown(stcb);
  				if (asoc->alternate) {
  					netp = asoc->alternate;
  				} else {
  					netp = asoc->primary_destination;
  				}
  				sctp_send_shutdown(stcb, netp);
  				sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWN,
  						 stcb->sctp_ep, stcb, netp);
  				sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
  						 stcb->sctp_ep, stcb, netp);
  			}
  		} else if ((SCTP_GET_STATE(asoc) == SCTP_STATE_SHUTDOWN_RECEIVED) &&
  			   (asoc->stream_queue_cnt == 0)) {
  			struct sctp_nets *netp;
  
  			if (asoc->state & SCTP_STATE_PARTIAL_MSG_LEFT) {
  				goto abort_out_now;
  			}
  			SCTP_STAT_DECR_GAUGE32(sctps_currestab);
  			SCTP_SET_STATE(asoc, SCTP_STATE_SHUTDOWN_ACK_SENT);
  			SCTP_CLEAR_SUBSTATE(asoc, SCTP_STATE_SHUTDOWN_PENDING);
  			sctp_stop_timers_for_shutdown(stcb);
  			if (asoc->alternate) {
  				netp = asoc->alternate;
  			} else {
  				netp = asoc->primary_destination;
  			}
  			sctp_send_shutdown_ack(stcb, netp);
  			sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNACK,
  					 stcb->sctp_ep, stcb, netp);
  		}
  	}
  	/*********************************************/
  	/* Here we perform PR-SCTP procedures        */
  	/* (section 4.2)                             */
  	/*********************************************/
  	/* C1. update advancedPeerAckPoint */
  	if (SCTP_TSN_GT(cumack, asoc->advanced_peer_ack_point)) {
  		asoc->advanced_peer_ack_point = cumack;
  	}
  	/* PR-Sctp issues need to be addressed too */
  	if ((asoc->prsctp_supported) && (asoc->pr_sctp_cnt > 0)) {
  		struct sctp_tmit_chunk *lchk;
  		uint32_t old_adv_peer_ack_point;
  
  		old_adv_peer_ack_point = asoc->advanced_peer_ack_point;
  		lchk = sctp_try_advance_peer_ack_point(stcb, asoc);
  		/* C3. See if we need to send a Fwd-TSN */
  		if (SCTP_TSN_GT(asoc->advanced_peer_ack_point, cumack)) {
  			/*
  			 * ISSUE with ECN, see FWD-TSN processing.
  			 */
  			if (SCTP_TSN_GT(asoc->advanced_peer_ack_point, old_adv_peer_ack_point)) {
  				send_forward_tsn(stcb, asoc);
  			} else if (lchk) {
  				/* try to FR fwd-tsn's that get lost too */
  				if (lchk->rec.data.fwd_tsn_cnt >= 3) {
  					send_forward_tsn(stcb, asoc);
  				}
  			}
  		}
  		if (lchk) {
  			/* Assure a timer is up */
  			sctp_timer_start(SCTP_TIMER_TYPE_SEND,
  					 stcb->sctp_ep, stcb, lchk->whoTo);
  		}
  	}
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_SACK_RWND_LOGGING_ENABLE) {
  		sctp_misc_ints(SCTP_SACK_RWND_UPDATE,
  			       rwnd,
  			       stcb->asoc.peers_rwnd,
  			       stcb->asoc.total_flight,
  			       stcb->asoc.total_output_queue_size);
  	}
  }
  
  void
  sctp_handle_sack(struct mbuf *m, int offset_seg, int offset_dup,
                   struct sctp_tcb *stcb,
                   uint16_t num_seg, uint16_t num_nr_seg, uint16_t num_dup,
                   int *abort_now, uint8_t flags,
                   uint32_t cum_ack, uint32_t rwnd, int ecne_seen)
  {
  	struct sctp_association *asoc;
  	struct sctp_tmit_chunk *tp1, *tp2;
  	uint32_t last_tsn, biggest_tsn_acked, biggest_tsn_newly_acked, this_sack_lowest_newack;
  	uint16_t wake_him = 0;
  	uint32_t send_s = 0;
  	long j;
  	int accum_moved = 0;
  	int will_exit_fast_recovery = 0;
  	uint32_t a_rwnd, old_rwnd;
  	int win_probe_recovery = 0;
  	int win_probe_recovered = 0;
  	struct sctp_nets *net = NULL;
  	int done_once;
  	int rto_ok = 1;
  	uint8_t reneged_all = 0;
  	uint8_t cmt_dac_flag;
  	/*
  	 * we take any chance we can to service our queues since we cannot
  	 * get awoken when the socket is read from :<
  	 */
  	/*
  	 * Now perform the actual SACK handling: 1) Verify that it is not an
  	 * old sack, if so discard. 2) If there is nothing left in the send
  	 * queue (cum-ack is equal to last acked) then you have a duplicate
  	 * too, update any rwnd change and verify no timers are running.
  	 * then return. 3) Process any new consequtive data i.e. cum-ack
  	 * moved process these first and note that it moved. 4) Process any
  	 * sack blocks. 5) Drop any acked from the queue. 6) Check for any
  	 * revoked blocks and mark. 7) Update the cwnd. 8) Nothing left,
  	 * sync up flightsizes and things, stop all timers and also check
  	 * for shutdown_pending state. If so then go ahead and send off the
  	 * shutdown. If in shutdown recv, send off the shutdown-ack and
  	 * start that timer, Ret. 9) Strike any non-acked things and do FR
  	 * procedure if needed being sure to set the FR flag. 10) Do pr-sctp
  	 * procedures. 11) Apply any FR penalties. 12) Assure we will SACK
  	 * if in shutdown_recv state.
  	 */
  	SCTP_TCB_LOCK_ASSERT(stcb);
  	/* CMT DAC algo */
  	this_sack_lowest_newack = 0;
  	SCTP_STAT_INCR(sctps_slowpath_sack);
  	last_tsn = cum_ack;
  	cmt_dac_flag = flags & SCTP_SACK_CMT_DAC;
  #ifdef SCTP_ASOCLOG_OF_TSNS
  	stcb->asoc.cumack_log[stcb->asoc.cumack_log_at] = cum_ack;
  	stcb->asoc.cumack_log_at++;
  	if (stcb->asoc.cumack_log_at > SCTP_TSN_LOG_SIZE) {
  		stcb->asoc.cumack_log_at = 0;
  	}
  #endif
  	a_rwnd = rwnd;
  
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LOG_SACK_ARRIVALS_ENABLE) {
  		sctp_misc_ints(SCTP_SACK_LOG_NORMAL, cum_ack,
  		               rwnd, stcb->asoc.last_acked_seq, stcb->asoc.peers_rwnd);
  	}
  
  	old_rwnd = stcb->asoc.peers_rwnd;
  	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_INDATA,
  		               __LINE__);
  	}
  	stcb->asoc.overall_error_count = 0;
  	asoc = &stcb->asoc;
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_SACK_LOGGING_ENABLE) {
  		sctp_log_sack(asoc->last_acked_seq,
  		              cum_ack,
  		              0,
  		              num_seg,
  		              num_dup,
  		              SCTP_LOG_NEW_SACK);
  	}
  	if ((num_dup) && (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE)) {
  		uint16_t i;
  		uint32_t *dupdata, dblock;
  
  		for (i = 0; i < num_dup; i++) {
  			dupdata = (uint32_t *)sctp_m_getptr(m, offset_dup + i * sizeof(uint32_t),
  			                                    sizeof(uint32_t), (uint8_t *)&dblock);
  			if (dupdata == NULL) {
  				break;
  			}
  			sctp_log_fr(*dupdata, 0, 0, SCTP_FR_DUPED);
  		}
  	}
  	if (SCTP_BASE_SYSCTL(sctp_strict_sacks)) {
  		/* reality check */
  		if (!TAILQ_EMPTY(&asoc->sent_queue)) {
  			tp1 = TAILQ_LAST(&asoc->sent_queue,
  			                 sctpchunk_listhead);
  			send_s = tp1->rec.data.TSN_seq + 1;
  		} else {
  			tp1 = NULL;
  			send_s = asoc->sending_seq;
  		}
  		if (SCTP_TSN_GE(cum_ack, send_s)) {
  			struct mbuf *op_err;
  			char msg[SCTP_DIAG_INFO_LEN];
  
  			/*
  			 * no way, we have not even sent this TSN out yet.
  			 * Peer is hopelessly messed up with us.
  			 */
  			SCTP_PRINTF("NEW cum_ack:%x send_s:%x is smaller or equal\n",
  			            cum_ack, send_s);
  			if (tp1) {
  				SCTP_PRINTF("Got send_s from tsn:%x + 1 of tp1:%p\n",
  				            tp1->rec.data.TSN_seq, (void *)tp1);
  			}
  		hopeless_peer:
  			*abort_now = 1;
  			/* XXX */
  			snprintf(msg, sizeof(msg), "Cum ack %8.8x greater or equal than TSN %8.8x",
  			         cum_ack, send_s);
  			op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  			stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_27;
  			sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  			return;
  		}
  	}
  	/**********************/
  	/* 1) check the range */
  	/**********************/
  	if (SCTP_TSN_GT(asoc->last_acked_seq, last_tsn)) {
  		/* acking something behind */
  		return;
  	}
  
  	/* update the Rwnd of the peer */
  	if (TAILQ_EMPTY(&asoc->sent_queue) &&
  	    TAILQ_EMPTY(&asoc->send_queue) &&
  	    (asoc->stream_queue_cnt == 0)) {
  		/* nothing left on send/sent and strmq */
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LOG_RWND_ENABLE) {
  			sctp_log_rwnd_set(SCTP_SET_PEER_RWND_VIA_SACK,
  			                  asoc->peers_rwnd, 0, 0, a_rwnd);
  		}
  		asoc->peers_rwnd = a_rwnd;
  		if (asoc->sent_queue_retran_cnt) {
  			asoc->sent_queue_retran_cnt = 0;
  		}
  		if (asoc->peers_rwnd < stcb->sctp_ep->sctp_ep.sctp_sws_sender) {
  			/* SWS sender side engages */
  			asoc->peers_rwnd = 0;
  		}
  		/* stop any timers */
  		TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  			sctp_timer_stop(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
  			                stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_28);
  			net->partial_bytes_acked = 0;
  			net->flight_size = 0;
  		}
  		asoc->total_flight = 0;
  		asoc->total_flight_count = 0;
  		return;
  	}
  	/*
  	 * We init netAckSz and netAckSz2 to 0. These are used to track 2
  	 * things. The total byte count acked is tracked in netAckSz AND
  	 * netAck2 is used to track the total bytes acked that are un-
  	 * amibguious and were never retransmitted. We track these on a per
  	 * destination address basis.
  	 */
  	TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  		if (SCTP_TSN_GT(cum_ack, net->cwr_window_tsn)) {
  			/* Drag along the window_tsn for cwr's */
  			net->cwr_window_tsn = cum_ack;
  		}
  		net->prev_cwnd = net->cwnd;
  		net->net_ack = 0;
  		net->net_ack2 = 0;
  
  		/*
  		 * CMT: Reset CUC and Fast recovery algo variables before
  		 * SACK processing
  		 */
  		net->new_pseudo_cumack = 0;
  		net->will_exit_fast_recovery = 0;
  		if (stcb->asoc.cc_functions.sctp_cwnd_prepare_net_for_sack) {
  			(*stcb->asoc.cc_functions.sctp_cwnd_prepare_net_for_sack)(stcb, net);
  		}
  	}
  	/* process the new consecutive TSN first */
  	TAILQ_FOREACH(tp1, &asoc->sent_queue, sctp_next) {
  		if (SCTP_TSN_GE(last_tsn, tp1->rec.data.TSN_seq)) {
  			if (tp1->sent != SCTP_DATAGRAM_UNSENT) {
  				accum_moved = 1;
  				if (tp1->sent < SCTP_DATAGRAM_ACKED) {
  					/*
  					 * If it is less than ACKED, it is
  					 * now no-longer in flight. Higher
  					 * values may occur during marking
  					 */
  					if ((tp1->whoTo->dest_state &
  					     SCTP_ADDR_UNCONFIRMED) &&
  					    (tp1->snd_count < 2)) {
  						/*
  						 * If there was no retran
  						 * and the address is
  						 * un-confirmed and we sent
  						 * there and are now
  						 * sacked.. its confirmed,
  						 * mark it so.
  						 */
  						tp1->whoTo->dest_state &=
  							~SCTP_ADDR_UNCONFIRMED;
  					}
  					if (tp1->sent < SCTP_DATAGRAM_RESEND) {
  						if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FLIGHT_LOGGING_ENABLE) {
  							sctp_misc_ints(SCTP_FLIGHT_LOG_DOWN_CA,
  							               tp1->whoTo->flight_size,
  							               tp1->book_size,
  							               (uintptr_t)tp1->whoTo,
  							               tp1->rec.data.TSN_seq);
  						}
  						sctp_flight_size_decrease(tp1);
  						sctp_total_flight_decrease(stcb, tp1);
  						if (stcb->asoc.cc_functions.sctp_cwnd_update_tsn_acknowledged) {
  							(*stcb->asoc.cc_functions.sctp_cwnd_update_tsn_acknowledged)(tp1->whoTo,
  														     tp1);
  						}
  					}
  					tp1->whoTo->net_ack += tp1->send_size;
  
  					/* CMT SFR and DAC algos */
  					this_sack_lowest_newack = tp1->rec.data.TSN_seq;
  					tp1->whoTo->saw_newack = 1;
  
  					if (tp1->snd_count < 2) {
  						/*
  						 * True non-retransmited
  						 * chunk
  						 */
  						tp1->whoTo->net_ack2 +=
  							tp1->send_size;
  
  						/* update RTO too? */
  						if (tp1->do_rtt) {
  							if (rto_ok) {
  								tp1->whoTo->RTO =
  									sctp_calculate_rto(stcb,
  											   asoc, tp1->whoTo,
  											   &tp1->sent_rcv_time,
  											   sctp_align_safe_nocopy,
  											   SCTP_RTT_FROM_DATA);
  								rto_ok = 0;
  							}
  							if (tp1->whoTo->rto_needed == 0) {
  								tp1->whoTo->rto_needed = 1;
  							}
  							tp1->do_rtt = 0;
  						}
  					}
  					/*
  					 * CMT: CUCv2 algorithm. From the
  					 * cumack'd TSNs, for each TSN being
  					 * acked for the first time, set the
  					 * following variables for the
  					 * corresp destination.
  					 * new_pseudo_cumack will trigger a
  					 * cwnd update.
  					 * find_(rtx_)pseudo_cumack will
  					 * trigger search for the next
  					 * expected (rtx-)pseudo-cumack.
  					 */
  					tp1->whoTo->new_pseudo_cumack = 1;
  					tp1->whoTo->find_pseudo_cumack = 1;
  					tp1->whoTo->find_rtx_pseudo_cumack = 1;
  
  
  					if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_SACK_LOGGING_ENABLE) {
  						sctp_log_sack(asoc->last_acked_seq,
  						              cum_ack,
  						              tp1->rec.data.TSN_seq,
  						              0,
  						              0,
  						              SCTP_LOG_TSN_ACKED);
  					}
  					if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
  						sctp_log_cwnd(stcb, tp1->whoTo, tp1->rec.data.TSN_seq, SCTP_CWND_LOG_FROM_SACK);
  					}
  				}
  				if (tp1->sent == SCTP_DATAGRAM_RESEND) {
  					sctp_ucount_decr(asoc->sent_queue_retran_cnt);
  #ifdef SCTP_AUDITING_ENABLED
  					sctp_audit_log(0xB3,
  					               (asoc->sent_queue_retran_cnt & 0x000000ff));
  #endif
  				}
  				if (tp1->rec.data.chunk_was_revoked) {
  					/* deflate the cwnd */
  					tp1->whoTo->cwnd -= tp1->book_size;
  					tp1->rec.data.chunk_was_revoked = 0;
  				}
  				if (tp1->sent != SCTP_DATAGRAM_NR_ACKED) {
  					tp1->sent = SCTP_DATAGRAM_ACKED;
  				}
  			}
  		} else {
  			break;
  		}
  	}
  	biggest_tsn_newly_acked = biggest_tsn_acked = last_tsn;
  	/* always set this up to cum-ack */
  	asoc->this_sack_highest_gap = last_tsn;
  
  	if ((num_seg > 0) || (num_nr_seg > 0)) {
  
  		/*
  		 * CMT: SFR algo (and HTNA) - this_sack_highest_newack has
  		 * to be greater than the cumack. Also reset saw_newack to 0
  		 * for all dests.
  		 */
  		TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  			net->saw_newack = 0;
  			net->this_sack_highest_newack = last_tsn;
  		}
  
  		/*
  		 * thisSackHighestGap will increase while handling NEW
  		 * segments this_sack_highest_newack will increase while
  		 * handling NEWLY ACKED chunks. this_sack_lowest_newack is
  		 * used for CMT DAC algo. saw_newack will also change.
  		 */
  		if (sctp_handle_segments(m, &offset_seg, stcb, asoc, last_tsn, &biggest_tsn_acked,
  			&biggest_tsn_newly_acked, &this_sack_lowest_newack,
  			num_seg, num_nr_seg, &rto_ok)) {
  			wake_him++;
  		}
  		if (SCTP_BASE_SYSCTL(sctp_strict_sacks)) {
  			/*
  			 * validate the biggest_tsn_acked in the gap acks if
  			 * strict adherence is wanted.
  			 */
  			if (SCTP_TSN_GE(biggest_tsn_acked, send_s)) {
  				/*
  				 * peer is either confused or we are under
  				 * attack. We must abort.
  				 */
  				SCTP_PRINTF("Hopeless peer! biggest_tsn_acked:%x largest seq:%x\n",
  				            biggest_tsn_acked, send_s);
  				goto hopeless_peer;
  			}
  		}
  	}
  	/*******************************************/
  	/* cancel ALL T3-send timer if accum moved */
  	/*******************************************/
  	if (asoc->sctp_cmt_on_off > 0) {
  		TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  			if (net->new_pseudo_cumack)
  				sctp_timer_stop(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
  				                stcb, net,
  				                SCTP_FROM_SCTP_INDATA + SCTP_LOC_29);
  
  		}
  	} else {
  		if (accum_moved) {
  			TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  				sctp_timer_stop(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
  				                stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_30);
  			}
  		}
  	}
  	/********************************************/
  	/* drop the acked chunks from the sentqueue */
  	/********************************************/
  	asoc->last_acked_seq = cum_ack;
  
  	TAILQ_FOREACH_SAFE(tp1, &asoc->sent_queue, sctp_next, tp2) {
  		if (SCTP_TSN_GT(tp1->rec.data.TSN_seq, cum_ack)) {
  			break;
  		}
  		if (tp1->sent != SCTP_DATAGRAM_NR_ACKED) {
  			if (asoc->strmout[tp1->rec.data.stream_number].chunks_on_queues > 0) {
  				asoc->strmout[tp1->rec.data.stream_number].chunks_on_queues--;
  #ifdef INVARIANTS
  			} else {
  				panic("No chunks on the queues for sid %u.", tp1->rec.data.stream_number);
  #endif
  			}
  		}
  		TAILQ_REMOVE(&asoc->sent_queue, tp1, sctp_next);
  		if (PR_SCTP_ENABLED(tp1->flags)) {
  			if (asoc->pr_sctp_cnt != 0)
  				asoc->pr_sctp_cnt--;
  		}
  		asoc->sent_queue_cnt--;
  		if (tp1->data) {
  			/* sa_ignore NO_NULL_CHK */
  			sctp_free_bufspace(stcb, asoc, tp1, 1);
  			sctp_m_freem(tp1->data);
  			tp1->data = NULL;
  			if (asoc->prsctp_supported && PR_SCTP_BUF_ENABLED(tp1->flags)) {
  				asoc->sent_queue_cnt_removeable--;
  			}
  		}
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_SACK_LOGGING_ENABLE) {
  			sctp_log_sack(asoc->last_acked_seq,
  			              cum_ack,
  			              tp1->rec.data.TSN_seq,
  			              0,
  			              0,
  			              SCTP_LOG_FREE_SENT);
  		}
  		sctp_free_a_chunk(stcb, tp1, SCTP_SO_NOT_LOCKED);
  		wake_him++;
  	}
  	if (TAILQ_EMPTY(&asoc->sent_queue) && (asoc->total_flight > 0)) {
  #ifdef INVARIANTS
  		panic("Warning flight size is postive and should be 0");
  #else
  		SCTP_PRINTF("Warning flight size incorrect should be 0 is %d\n",
  		            asoc->total_flight);
  #endif
  		asoc->total_flight = 0;
  	}
  
  #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)) ||
  			    (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);
  			}
  		}
  	} else if ((wake_him) && (stcb->sctp_socket)) {
  #else
  	/* sa_ignore NO_NULL_CHK */
  	if ((wake_him) && (stcb->sctp_socket)) {
  #endif
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		struct socket *so;
  
  #endif
  		SOCKBUF_LOCK(&stcb->sctp_socket->so_snd);
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_WAKE_LOGGING_ENABLE) {
  			sctp_wakeup_log(stcb, wake_him, SCTP_WAKESND_FROM_SACK);
  		}
  #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
  		sctp_sowwakeup_locked(stcb->sctp_ep, stcb->sctp_socket);
  #if defined(__APPLE__) || defined(SCTP_SO_LOCK_TESTING)
  		SCTP_SOCKET_UNLOCK(so, 1);
  #endif
  	} else {
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_WAKE_LOGGING_ENABLE) {
  			sctp_wakeup_log(stcb, wake_him, SCTP_NOWAKE_FROM_SACK);
  		}
  	}
  
  	if (asoc->fast_retran_loss_recovery && accum_moved) {
  		if (SCTP_TSN_GE(asoc->last_acked_seq, asoc->fast_recovery_tsn)) {
  			/* Setup so we will exit RFC2582 fast recovery */
  			will_exit_fast_recovery = 1;
  		}
  	}
  	/*
  	 * Check for revoked fragments:
  	 *
  	 * if Previous sack - Had no frags then we can't have any revoked if
  	 * Previous sack - Had frag's then - If we now have frags aka
  	 * num_seg > 0 call sctp_check_for_revoked() to tell if peer revoked
  	 * some of them. else - The peer revoked all ACKED fragments, since
  	 * we had some before and now we have NONE.
  	 */
  
  	if (num_seg) {
  		sctp_check_for_revoked(stcb, asoc, cum_ack, biggest_tsn_acked);
  		asoc->saw_sack_with_frags = 1;
  	} else if (asoc->saw_sack_with_frags) {
  		int cnt_revoked = 0;
  
  		/* Peer revoked all dg's marked or acked */
  		TAILQ_FOREACH(tp1, &asoc->sent_queue, sctp_next) {
  			if (tp1->sent == SCTP_DATAGRAM_ACKED) {
  				tp1->sent = SCTP_DATAGRAM_SENT;
  				if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FLIGHT_LOGGING_ENABLE) {
  					sctp_misc_ints(SCTP_FLIGHT_LOG_UP_REVOKE,
  					               tp1->whoTo->flight_size,
  					               tp1->book_size,
  					               (uintptr_t)tp1->whoTo,
  					               tp1->rec.data.TSN_seq);
  				}
  				sctp_flight_size_increase(tp1);
  				sctp_total_flight_increase(stcb, tp1);
  				tp1->rec.data.chunk_was_revoked = 1;
  				/*
  				 * To ensure that this increase in
  				 * flightsize, which is artificial,
  				 * does not throttle the sender, we
  				 * also increase the cwnd
  				 * artificially.
  				 */
  				tp1->whoTo->cwnd += tp1->book_size;
  				cnt_revoked++;
  			}
  		}
  		if (cnt_revoked) {
  			reneged_all = 1;
  		}
  		asoc->saw_sack_with_frags = 0;
  	}
  	if (num_nr_seg > 0)
  		asoc->saw_sack_with_nr_frags = 1;
  	else
  		asoc->saw_sack_with_nr_frags = 0;
  
  	/* JRS - Use the congestion control given in the CC module */
  	if (ecne_seen == 0) {
  		TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  			if (net->net_ack2 > 0) {
  				/*
  				 * Karn's rule applies to clearing error count, this
  				 * is optional.
  				 */
  				net->error_count = 0;
  				if (!(net->dest_state & SCTP_ADDR_REACHABLE)) {
  					/* addr came good */
  					net->dest_state |= SCTP_ADDR_REACHABLE;
  					sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_UP, stcb,
  					                0, (void *)net, SCTP_SO_NOT_LOCKED);
  				}
  
  				if (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;
  					}
  				}
  
  				if (net->dest_state & SCTP_ADDR_PF) {
  					net->dest_state &= ~SCTP_ADDR_PF;
  					sctp_timer_stop(SCTP_TIMER_TYPE_HEARTBEAT,
  					                stcb->sctp_ep, stcb, net,
  					                SCTP_FROM_SCTP_INDATA + SCTP_LOC_31);
  					sctp_timer_start(SCTP_TIMER_TYPE_HEARTBEAT, stcb->sctp_ep, stcb, net);
  					asoc->cc_functions.sctp_cwnd_update_exit_pf(stcb, net);
  					/* Done with this net */
  					net->net_ack = 0;
  				}
  				/* restore any doubled timers */
  				net->RTO = (net->lastsa >> SCTP_RTT_SHIFT) + net->lastsv;
  				if (net->RTO < stcb->asoc.minrto) {
  					net->RTO = stcb->asoc.minrto;
  				}
  				if (net->RTO > stcb->asoc.maxrto) {
  					net->RTO = stcb->asoc.maxrto;
  				}
  			}
  		}
  		asoc->cc_functions.sctp_cwnd_update_after_sack(stcb, asoc, accum_moved, reneged_all, will_exit_fast_recovery);
  	}
  
  	if (TAILQ_EMPTY(&asoc->sent_queue)) {
  		/* nothing left in-flight */
  		TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  			/* stop all timers */
  			sctp_timer_stop(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
  			                stcb, net,
  			                SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
  			net->flight_size = 0;
  			net->partial_bytes_acked = 0;
  		}
  		asoc->total_flight = 0;
  		asoc->total_flight_count = 0;
  	}
  
  	/**********************************/
  	/* Now what about shutdown issues */
  	/**********************************/
  	if (TAILQ_EMPTY(&asoc->send_queue) && TAILQ_EMPTY(&asoc->sent_queue)) {
  		/* nothing left on sendqueue.. consider done */
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LOG_RWND_ENABLE) {
  			sctp_log_rwnd_set(SCTP_SET_PEER_RWND_VIA_SACK,
  			                  asoc->peers_rwnd, 0, 0, a_rwnd);
  		}
  		asoc->peers_rwnd = a_rwnd;
  		if (asoc->peers_rwnd < stcb->sctp_ep->sctp_ep.sctp_sws_sender) {
  			/* SWS sender side engages */
  			asoc->peers_rwnd = 0;
  		}
  		/* clean up */
  		if ((asoc->stream_queue_cnt == 1) &&
  		    ((asoc->state & SCTP_STATE_SHUTDOWN_PENDING) ||
  		     (asoc->state & SCTP_STATE_SHUTDOWN_RECEIVED)) &&
  		    (asoc->locked_on_sending)
  			) {
  			struct sctp_stream_queue_pending *sp;
  			/* I may be in a state where we got
  			 * all across.. but cannot write more due
  			 * to a shutdown... we abort since the
  			 * user did not indicate EOR in this case.
  			 */
  			sp = TAILQ_LAST(&((asoc->locked_on_sending)->outqueue),
  			                sctp_streamhead);
  			if ((sp) && (sp->length == 0)) {
  				asoc->locked_on_sending = NULL;
  				if (sp->msg_is_complete) {
  					asoc->stream_queue_cnt--;
  				} else {
  					asoc->state |= SCTP_STATE_PARTIAL_MSG_LEFT;
  					asoc->stream_queue_cnt--;
  				}
  			}
  		}
  		if ((asoc->state & SCTP_STATE_SHUTDOWN_PENDING) &&
  		    (asoc->stream_queue_cnt == 0)) {
  			if (asoc->state & SCTP_STATE_PARTIAL_MSG_LEFT) {
  				/* Need to abort here */
  				struct mbuf *op_err;
  
  			abort_out_now:
  				*abort_now = 1;
  				/* XXX */
  				op_err = sctp_generate_cause(SCTP_CAUSE_USER_INITIATED_ABT, "");
  				stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_33;
  				sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  				return;
  			} else {
  				struct sctp_nets *netp;
  
  				if ((SCTP_GET_STATE(asoc) == SCTP_STATE_OPEN) ||
  				    (SCTP_GET_STATE(asoc) == SCTP_STATE_SHUTDOWN_RECEIVED)) {
  					SCTP_STAT_DECR_GAUGE32(sctps_currestab);
  				}
  				SCTP_SET_STATE(asoc, SCTP_STATE_SHUTDOWN_SENT);
  				SCTP_CLEAR_SUBSTATE(asoc, SCTP_STATE_SHUTDOWN_PENDING);
  				sctp_stop_timers_for_shutdown(stcb);
  				if (asoc->alternate) {
  					netp = asoc->alternate;
  				} else {
  					netp = asoc->primary_destination;
  				}
  				sctp_send_shutdown(stcb, netp);
  				sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWN,
  				                 stcb->sctp_ep, stcb, netp);
  				sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
  				                 stcb->sctp_ep, stcb, netp);
  			}
  			return;
  		} else if ((SCTP_GET_STATE(asoc) == SCTP_STATE_SHUTDOWN_RECEIVED) &&
  			   (asoc->stream_queue_cnt == 0)) {
  			struct sctp_nets *netp;
  
  			if (asoc->state & SCTP_STATE_PARTIAL_MSG_LEFT) {
  				goto abort_out_now;
  			}
  			SCTP_STAT_DECR_GAUGE32(sctps_currestab);
  			SCTP_SET_STATE(asoc, SCTP_STATE_SHUTDOWN_ACK_SENT);
  			SCTP_CLEAR_SUBSTATE(asoc, SCTP_STATE_SHUTDOWN_PENDING);
  			sctp_stop_timers_for_shutdown(stcb);
  			if (asoc->alternate) {
  				netp = asoc->alternate;
  			} else {
  				netp = asoc->primary_destination;
  			}
  			sctp_send_shutdown_ack(stcb, netp);
  			sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNACK,
  			                 stcb->sctp_ep, stcb, netp);
  			return;
  		}
  	}
  	/*
  	 * Now here we are going to recycle net_ack for a different use...
  	 * HEADS UP.
  	 */
  	TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  		net->net_ack = 0;
  	}
  
  	/*
  	 * CMT DAC algorithm: If SACK DAC flag was 0, then no extra marking
  	 * to be done. Setting this_sack_lowest_newack to the cum_ack will
  	 * automatically ensure that.
  	 */
  	if ((asoc->sctp_cmt_on_off > 0) &&
  	    SCTP_BASE_SYSCTL(sctp_cmt_use_dac) &&
  	    (cmt_dac_flag == 0)) {
  		this_sack_lowest_newack = cum_ack;
  	}
  	if ((num_seg > 0) || (num_nr_seg > 0)) {
  		sctp_strike_gap_ack_chunks(stcb, asoc, biggest_tsn_acked,
  		                           biggest_tsn_newly_acked, this_sack_lowest_newack, accum_moved);
  	}
  	/* JRS - Use the congestion control given in the CC module */
  	asoc->cc_functions.sctp_cwnd_update_after_fr(stcb, asoc);
  
  	/* Now are we exiting loss recovery ? */
  	if (will_exit_fast_recovery) {
  		/* Ok, we must exit fast recovery */
  		asoc->fast_retran_loss_recovery = 0;
  	}
  	if ((asoc->sat_t3_loss_recovery) &&
  	    SCTP_TSN_GE(asoc->last_acked_seq, asoc->sat_t3_recovery_tsn)) {
  		/* end satellite t3 loss recovery */
  		asoc->sat_t3_loss_recovery = 0;
  	}
  	/*
  	 * CMT Fast recovery
  	 */
  	TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  		if (net->will_exit_fast_recovery) {
  			/* Ok, we must exit fast recovery */
  			net->fast_retran_loss_recovery = 0;
  		}
  	}
  
  	/* Adjust and set the new rwnd value */
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LOG_RWND_ENABLE) {
  		sctp_log_rwnd_set(SCTP_SET_PEER_RWND_VIA_SACK,
  		                  asoc->peers_rwnd, asoc->total_flight, (asoc->total_flight_count * SCTP_BASE_SYSCTL(sctp_peer_chunk_oh)), a_rwnd);
  	}
  	asoc->peers_rwnd = sctp_sbspace_sub(a_rwnd,
  	                                    (uint32_t) (asoc->total_flight + (asoc->total_flight_count * SCTP_BASE_SYSCTL(sctp_peer_chunk_oh))));
  	if (asoc->peers_rwnd < stcb->sctp_ep->sctp_ep.sctp_sws_sender) {
  		/* SWS sender side engages */
  		asoc->peers_rwnd = 0;
  	}
  	if (asoc->peers_rwnd > old_rwnd) {
  		win_probe_recovery = 1;
  	}
  
  	/*
  	 * Now we must setup so we have a timer up for anyone with
  	 * outstanding data.
  	 */
  	done_once = 0;
  again:
  	j = 0;
  	TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  		if (win_probe_recovery && (net->window_probe)) {
  			win_probe_recovered = 1;
  			/*-
  			 * Find first chunk that was used with
  			 * window probe and clear the event. Put
  			 * it back into the send queue as if has
  			 * not been sent.
  			 */
  			TAILQ_FOREACH(tp1, &asoc->sent_queue, sctp_next) {
  				if (tp1->window_probe) {
  					sctp_window_probe_recovery(stcb, asoc, tp1);
  					break;
  				}
  			}
  		}
  		if (net->flight_size) {
  			j++;
  			if (!SCTP_OS_TIMER_PENDING(&net->rxt_timer.timer)) {
  				sctp_timer_start(SCTP_TIMER_TYPE_SEND,
  				                 stcb->sctp_ep, stcb, net);
  			}
  			if (net->window_probe) {
  				net->window_probe = 0;
  			}
  		} else {
  			if (net->window_probe) {
  				/* In window probes we must assure a timer is still running there */
  				if (!SCTP_OS_TIMER_PENDING(&net->rxt_timer.timer)) {
  					sctp_timer_start(SCTP_TIMER_TYPE_SEND,
  					                 stcb->sctp_ep, stcb, net);
  
  				}
  			} else if (SCTP_OS_TIMER_PENDING(&net->rxt_timer.timer)) {
  				sctp_timer_stop(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
  				                stcb, net,
  				                SCTP_FROM_SCTP_INDATA + SCTP_LOC_34);
  			}
  		}
  	}
  	if ((j == 0) &&
  	    (!TAILQ_EMPTY(&asoc->sent_queue)) &&
  	    (asoc->sent_queue_retran_cnt == 0) &&
  	    (win_probe_recovered == 0) &&
  	    (done_once == 0)) {
  		/* huh, this should not happen unless all packets
  		 * are PR-SCTP and marked to skip of course.
  		 */
  		if (sctp_fs_audit(asoc)) {
  			TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
  				net->flight_size = 0;
  			}
  			asoc->total_flight = 0;
  			asoc->total_flight_count = 0;
  			asoc->sent_queue_retran_cnt = 0;
  			TAILQ_FOREACH(tp1, &asoc->sent_queue, sctp_next) {
  				if (tp1->sent < SCTP_DATAGRAM_RESEND) {
  					sctp_flight_size_increase(tp1);
  					sctp_total_flight_increase(stcb, tp1);
  				} else if (tp1->sent == SCTP_DATAGRAM_RESEND) {
  					sctp_ucount_incr(asoc->sent_queue_retran_cnt);
  				}
  			}
  		}
  		done_once = 1;
  		goto again;
  	}
  	/*********************************************/
  	/* Here we perform PR-SCTP procedures        */
  	/* (section 4.2)                             */
  	/*********************************************/
  	/* C1. update advancedPeerAckPoint */
  	if (SCTP_TSN_GT(cum_ack, asoc->advanced_peer_ack_point)) {
  		asoc->advanced_peer_ack_point = cum_ack;
  	}
  	/* C2. try to further move advancedPeerAckPoint ahead */
  	if ((asoc->prsctp_supported) && (asoc->pr_sctp_cnt > 0)) {
  		struct sctp_tmit_chunk *lchk;
  		uint32_t old_adv_peer_ack_point;
  
  		old_adv_peer_ack_point = asoc->advanced_peer_ack_point;
  		lchk = sctp_try_advance_peer_ack_point(stcb, asoc);
  		/* C3. See if we need to send a Fwd-TSN */
  		if (SCTP_TSN_GT(asoc->advanced_peer_ack_point, cum_ack)) {
  			/*
  			 * ISSUE with ECN, see FWD-TSN processing.
  			 */
  			if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LOG_TRY_ADVANCE) {
  				sctp_misc_ints(SCTP_FWD_TSN_CHECK,
  				               0xee, cum_ack, asoc->advanced_peer_ack_point,
  				               old_adv_peer_ack_point);
  			}
  			if (SCTP_TSN_GT(asoc->advanced_peer_ack_point, old_adv_peer_ack_point)) {
  				send_forward_tsn(stcb, asoc);
  			} else if (lchk) {
  				/* try to FR fwd-tsn's that get lost too */
  				if (lchk->rec.data.fwd_tsn_cnt >= 3) {
  					send_forward_tsn(stcb, asoc);
  				}
  			}
  		}
  		if (lchk) {
  			/* Assure a timer is up */
  			sctp_timer_start(SCTP_TIMER_TYPE_SEND,
  			                 stcb->sctp_ep, stcb, lchk->whoTo);
  		}
  	}
  	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_SACK_RWND_LOGGING_ENABLE) {
  		sctp_misc_ints(SCTP_SACK_RWND_UPDATE,
  		               a_rwnd,
  		               stcb->asoc.peers_rwnd,
  		               stcb->asoc.total_flight,
  		               stcb->asoc.total_output_queue_size);
  	}
  }
  
  void
  sctp_update_acked(struct sctp_tcb *stcb, struct sctp_shutdown_chunk *cp, int *abort_flag)
  {
  	/* Copy cum-ack */
  	uint32_t cum_ack, a_rwnd;
  
  	cum_ack = ntohl(cp->cumulative_tsn_ack);
  	/* Arrange so a_rwnd does NOT change */
  	a_rwnd = stcb->asoc.peers_rwnd + stcb->asoc.total_flight;
  
  	/* Now call the express sack handling */
  	sctp_express_handle_sack(stcb, cum_ack, a_rwnd, abort_flag, 0);
  }
  
  static void
  sctp_kick_prsctp_reorder_queue(struct sctp_tcb *stcb,
      struct sctp_stream_in *strmin)
  {
  	struct sctp_queued_to_read *ctl, *nctl;
  	struct sctp_association *asoc;
  	uint16_t tt;
  
  	asoc = &stcb->asoc;
  	tt = strmin->last_sequence_delivered;
  	/*
  	 * First deliver anything prior to and including the stream no that
  	 * came in
  	 */
  	TAILQ_FOREACH_SAFE(ctl, &strmin->inqueue, next, nctl) {
  		if (SCTP_SSN_GE(tt, ctl->sinfo_ssn)) {
  			/* this is deliverable now */
  			TAILQ_REMOVE(&strmin->inqueue, ctl, next);
  			/* subtract pending on streams */
  			asoc->size_on_all_streams -= ctl->length;
  			sctp_ucount_decr(asoc->cnt_on_all_streams);
  			/* deliver it to at least the delivery-q */
  			if (stcb->sctp_socket) {
  				sctp_mark_non_revokable(asoc, ctl->sinfo_tsn);
  				sctp_add_to_readq(stcb->sctp_ep, stcb,
  						  ctl,
  						  &stcb->sctp_socket->so_rcv, 1, SCTP_READ_LOCK_HELD, SCTP_SO_NOT_LOCKED);
  			}
  		} else {
  			/* no more delivery now. */
  			break;
  		}
  	}
  	/*
  	 * now we must deliver things in queue the normal way  if any are
  	 * now ready.
  	 */
  	tt = strmin->last_sequence_delivered + 1;
  	TAILQ_FOREACH_SAFE(ctl, &strmin->inqueue, next, nctl) {
  		if (tt == ctl->sinfo_ssn) {
  			/* this is deliverable now */
  			TAILQ_REMOVE(&strmin->inqueue, ctl, next);
  			/* subtract pending on streams */
  			asoc->size_on_all_streams -= ctl->length;
  			sctp_ucount_decr(asoc->cnt_on_all_streams);
  			/* deliver it to at least the delivery-q */
  			strmin->last_sequence_delivered = ctl->sinfo_ssn;
  			if (stcb->sctp_socket) {
  				sctp_mark_non_revokable(asoc, ctl->sinfo_tsn);
  				sctp_add_to_readq(stcb->sctp_ep, stcb,
  						  ctl,
  						  &stcb->sctp_socket->so_rcv, 1, SCTP_READ_LOCK_HELD, SCTP_SO_NOT_LOCKED);
  
  			}
  			tt = strmin->last_sequence_delivered + 1;
  		} else {
  			break;
  		}
  	}
  }
  
  static void
  sctp_flush_reassm_for_str_seq(struct sctp_tcb *stcb,
  	struct sctp_association *asoc,
  	uint16_t stream, uint16_t seq)
  {
  	struct sctp_tmit_chunk *chk, *nchk;
  
  	/* For each one on here see if we need to toss it */
  	/*
  	 * For now large messages held on the reasmqueue that are
  	 * complete will be tossed too. We could in theory do more
  	 * work to spin through and stop after dumping one msg aka
  	 * seeing the start of a new msg at the head, and call the
  	 * delivery function... to see if it can be delivered... But
  	 * for now we just dump everything on the queue.
  	 */
  	TAILQ_FOREACH_SAFE(chk, &asoc->reasmqueue, sctp_next, nchk) {
  		/* Do not toss it if on a different stream or
  		 * marked for unordered delivery in which case
  		 * the stream sequence number has no meaning.
  		 */
  		if ((chk->rec.data.stream_number != stream) ||
  		    ((chk->rec.data.rcv_flags & SCTP_DATA_UNORDERED) == SCTP_DATA_UNORDERED)) {
  				continue;
  		}
  		if (chk->rec.data.stream_seq == seq) {
  			/* It needs to be tossed */
  			TAILQ_REMOVE(&asoc->reasmqueue, chk, sctp_next);
  			if (SCTP_TSN_GT(chk->rec.data.TSN_seq, asoc->tsn_last_delivered)) {
  				asoc->tsn_last_delivered = chk->rec.data.TSN_seq;
  				asoc->str_of_pdapi = chk->rec.data.stream_number;
  				asoc->ssn_of_pdapi = chk->rec.data.stream_seq;
  				asoc->fragment_flags = chk->rec.data.rcv_flags;
  			}
  			asoc->size_on_reasm_queue -= chk->send_size;
  			sctp_ucount_decr(asoc->cnt_on_reasm_queue);
  
  			/* Clear up any stream problem */
  			if ((chk->rec.data.rcv_flags & SCTP_DATA_UNORDERED) != SCTP_DATA_UNORDERED &&
  			    SCTP_SSN_GT(chk->rec.data.stream_seq, asoc->strmin[chk->rec.data.stream_number].last_sequence_delivered)) {
  				/*
  				 * We must dump forward this streams
  				 * sequence number if the chunk is
  				 * not unordered that is being
  				 * skipped. There is a chance that
  				 * if the peer does not include the
  				 * last fragment in its FWD-TSN we
  				 * WILL have a problem here since
  				 * you would have a partial chunk in
  				 * queue that may not be
  				 * deliverable. Also if a Partial
  				 * delivery API as started the user
  				 * may get a partial chunk. The next
  				 * read returning a new chunk...
  				 * really ugly but I see no way
  				 * around it! Maybe a notify??
  				 */
  				asoc->strmin[chk->rec.data.stream_number].last_sequence_delivered = chk->rec.data.stream_seq;
  			}
  			if (chk->data) {
  				sctp_m_freem(chk->data);
  				chk->data = NULL;
  			}
  			sctp_free_a_chunk(stcb, chk, SCTP_SO_NOT_LOCKED);
  		} else if (SCTP_SSN_GT(chk->rec.data.stream_seq, seq)) {
  			/* If the stream_seq is > than the purging one, we are done */
  			break;
  		}
  	}
  }
  
  
  void
  sctp_handle_forward_tsn(struct sctp_tcb *stcb,
                          struct sctp_forward_tsn_chunk *fwd,
                          int *abort_flag, struct mbuf *m ,int offset)
  {
  	/* The pr-sctp fwd tsn */
  	/*
  	 * here we will perform all the data receiver side steps for
  	 * processing FwdTSN, as required in by pr-sctp draft:
  	 *
  	 * Assume we get FwdTSN(x):
  	 *
  	 * 1) update local cumTSN to x 2) try to further advance cumTSN to x +
  	 * others we have 3) examine and update re-ordering queue on
  	 * pr-in-streams 4) clean up re-assembly queue 5) Send a sack to
  	 * report where we are.
  	 */
  	struct sctp_association *asoc;
  	uint32_t new_cum_tsn, gap;
  	unsigned int i, fwd_sz, m_size;
  	uint32_t str_seq;
  	struct sctp_stream_in *strm;
  	struct sctp_tmit_chunk *chk, *nchk;
  	struct sctp_queued_to_read *ctl, *sv;
  
  	asoc = &stcb->asoc;
  	if ((fwd_sz = ntohs(fwd->ch.chunk_length)) < sizeof(struct sctp_forward_tsn_chunk)) {
  		SCTPDBG(SCTP_DEBUG_INDATA1,
  			"Bad size too small/big fwd-tsn\n");
  		return;
  	}
  	m_size = (stcb->asoc.mapping_array_size << 3);
  	/*************************************************************/
  	/* 1. Here we update local cumTSN and shift the bitmap array */
  	/*************************************************************/
  	new_cum_tsn = ntohl(fwd->new_cumulative_tsn);
  
  	if (SCTP_TSN_GE(asoc->cumulative_tsn, new_cum_tsn)) {
  		/* Already got there ... */
  		return;
  	}
  	/*
  	 * now we know the new TSN is more advanced, let's find the actual
  	 * gap
  	 */
  	SCTP_CALC_TSN_TO_GAP(gap, new_cum_tsn, asoc->mapping_array_base_tsn);
  	asoc->cumulative_tsn = new_cum_tsn;
  	if (gap >= m_size) {
  		if ((long)gap > sctp_sbspace(&stcb->asoc, &stcb->sctp_socket->so_rcv)) {
  			struct mbuf *op_err;
  			char msg[SCTP_DIAG_INFO_LEN];
  
  			/*
  			 * out of range (of single byte chunks in the rwnd I
  			 * give out). This must be an attacker.
  			 */
  			*abort_flag = 1;
  			snprintf(msg, sizeof(msg),
  			         "New cum ack %8.8x too high, highest TSN %8.8x",
  			         new_cum_tsn, asoc->highest_tsn_inside_map);
  			op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
  			stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_35;
  			sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, SCTP_SO_NOT_LOCKED);
  			return;
  		}
  		SCTP_STAT_INCR(sctps_fwdtsn_map_over);
  
  		memset(stcb->asoc.mapping_array, 0, stcb->asoc.mapping_array_size);
  		asoc->mapping_array_base_tsn = new_cum_tsn + 1;
  		asoc->highest_tsn_inside_map = new_cum_tsn;
  
  		memset(stcb->asoc.nr_mapping_array, 0, stcb->asoc.mapping_array_size);
  		asoc->highest_tsn_inside_nr_map = new_cum_tsn;
  
  		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_MAP_LOGGING_ENABLE) {
  			sctp_log_map(0, 3, asoc->highest_tsn_inside_map, SCTP_MAP_SLIDE_RESULT);
  		}
  	} else {
  		SCTP_TCB_LOCK_ASSERT(stcb);
  		for (i = 0; i <= gap; i++) {
  			if (!SCTP_IS_TSN_PRESENT(asoc->mapping_array, i) &&
  			    !SCTP_IS_TSN_PRESENT(asoc->nr_mapping_array, i)) {
  				SCTP_SET_TSN_PRESENT(asoc->nr_mapping_array, i);
  				if (SCTP_TSN_GT(asoc->mapping_array_base_tsn + i, asoc->highest_tsn_inside_nr_map)) {
  					asoc->highest_tsn_inside_nr_map = asoc->mapping_array_base_tsn + i;
  				}
  			}
  		}
  	}
  	/*************************************************************/
  	/* 2. Clear up re-assembly queue                             */
  	/*************************************************************/
  	/*
  	 * First service it if pd-api is up, just in case we can progress it
  	 * forward
  	 */
  	if (asoc->fragmented_delivery_inprogress) {
  		sctp_service_reassembly(stcb, asoc);
  	}
  	/* For each one on here see if we need to toss it */
  	/*
  	 * For now large messages held on the reasmqueue that are
  	 * complete will be tossed too. We could in theory do more
  	 * work to spin through and stop after dumping one msg aka
  	 * seeing the start of a new msg at the head, and call the
  	 * delivery function... to see if it can be delivered... But
  	 * for now we just dump everything on the queue.
  	 */
  	TAILQ_FOREACH_SAFE(chk, &asoc->reasmqueue, sctp_next, nchk) {
  		if (SCTP_TSN_GE(new_cum_tsn, chk->rec.data.TSN_seq)) {
  			/* It needs to be tossed */
  			TAILQ_REMOVE(&asoc->reasmqueue, chk, sctp_next);
  			if (SCTP_TSN_GT(chk->rec.data.TSN_seq, asoc->tsn_last_delivered)) {
  				asoc->tsn_last_delivered = chk->rec.data.TSN_seq;
  				asoc->str_of_pdapi = chk->rec.data.stream_number;
  				asoc->ssn_of_pdapi = chk->rec.data.stream_seq;
  				asoc->fragment_flags = chk->rec.data.rcv_flags;
  			}
  			asoc->size_on_reasm_queue -= chk->send_size;
  			sctp_ucount_decr(asoc->cnt_on_reasm_queue);
  
  			/* Clear up any stream problem */
  			if ((chk->rec.data.rcv_flags & SCTP_DATA_UNORDERED) != SCTP_DATA_UNORDERED &&
  			    SCTP_SSN_GT(chk->rec.data.stream_seq, asoc->strmin[chk->rec.data.stream_number].last_sequence_delivered)) {
  				/*
  				 * We must dump forward this streams
  				 * sequence number if the chunk is
  				 * not unordered that is being
  				 * skipped. There is a chance that
  				 * if the peer does not include the
  				 * last fragment in its FWD-TSN we
  				 * WILL have a problem here since
  				 * you would have a partial chunk in
  				 * queue that may not be
  				 * deliverable. Also if a Partial
  				 * delivery API as started the user
  				 * may get a partial chunk. The next
  				 * read returning a new chunk...
  				 * really ugly but I see no way
  				 * around it! Maybe a notify??
  				 */
  				asoc->strmin[chk->rec.data.stream_number].last_sequence_delivered = chk->rec.data.stream_seq;
  			}
  			if (chk->data) {
  				sctp_m_freem(chk->data);
  				chk->data = NULL;
  			}
  			sctp_free_a_chunk(stcb, chk, SCTP_SO_NOT_LOCKED);
  		} else {
  			/*
  			 * Ok we have gone beyond the end of the
  			 * fwd-tsn's mark.
  			 */
  			break;
  		}
  	}
  	/*******************************************************/
  	/* 3. Update the PR-stream re-ordering queues and fix  */
  	/*    delivery issues as needed.                       */
  	/*******************************************************/
  	fwd_sz -= sizeof(*fwd);
  	if (m && fwd_sz) {
  		/* New method. */
  		unsigned int num_str;
  		struct sctp_strseq *stseq, strseqbuf;
  		offset += sizeof(*fwd);
  
  		SCTP_INP_READ_LOCK(stcb->sctp_ep);
  		num_str = fwd_sz / sizeof(struct sctp_strseq);
  		for (i = 0; i < num_str; i++) {
  			uint16_t st;
  			stseq = (struct sctp_strseq *)sctp_m_getptr(m, offset,
  								    sizeof(struct sctp_strseq),
  								    (uint8_t *)&strseqbuf);
  			offset += sizeof(struct sctp_strseq);
  			if (stseq == NULL) {
  				break;
  			}
  			/* Convert */
  			st = ntohs(stseq->stream);
  			stseq->stream = st;
  			st = ntohs(stseq->sequence);
  			stseq->sequence = st;
  
  			/* now process */
  
  			/*
  			 * Ok we now look for the stream/seq on the read queue
  			 * where its not all delivered. If we find it we transmute the
  			 * read entry into a PDI_ABORTED.
  			 */
  			if (stseq->stream >= asoc->streamincnt) {
  				/* screwed up streams, stop!  */
  				break;
  			}
  			if ((asoc->str_of_pdapi == stseq->stream) &&
  			    (asoc->ssn_of_pdapi == stseq->sequence)) {
  				/* If this is the one we were partially delivering
  				 * now then we no longer are. Note this will change
  				 * with the reassembly re-write.
  				 */
  				asoc->fragmented_delivery_inprogress = 0;
  			}
  			sctp_flush_reassm_for_str_seq(stcb, asoc, stseq->stream, stseq->sequence);
  			TAILQ_FOREACH(ctl, &stcb->sctp_ep->read_queue, next) {
  				if ((ctl->sinfo_stream == stseq->stream) &&
  				    (ctl->sinfo_ssn == stseq->sequence)) {
  					str_seq = (stseq->stream << 16) | stseq->sequence;
  					ctl->end_added = 1;
  					ctl->pdapi_aborted = 1;
  					sv = stcb->asoc.control_pdapi;
  					stcb->asoc.control_pdapi = ctl;
  					sctp_ulp_notify(SCTP_NOTIFY_PARTIAL_DELVIERY_INDICATION,
  					                stcb,
  					                SCTP_PARTIAL_DELIVERY_ABORTED,
  					                (void *)&str_seq,
  							SCTP_SO_NOT_LOCKED);
  					stcb->asoc.control_pdapi = sv;
  					break;
  				} else if ((ctl->sinfo_stream == stseq->stream) &&
  					   SCTP_SSN_GT(ctl->sinfo_ssn, stseq->sequence)) {
  					/* We are past our victim SSN */
  					break;
  				}
  			}
  			strm = &asoc->strmin[stseq->stream];
  			if (SCTP_SSN_GT(stseq->sequence, strm->last_sequence_delivered)) {
  				/* Update the sequence number */
  				strm->last_sequence_delivered = stseq->sequence;
  			}
  			/* now kick the stream the new way */
                          /*sa_ignore NO_NULL_CHK*/
  			sctp_kick_prsctp_reorder_queue(stcb, strm);
  		}
  		SCTP_INP_READ_UNLOCK(stcb->sctp_ep);
  	}
  	/*
  	 * Now slide thing forward.
  	 */
  	sctp_slide_mapping_arrays(stcb);
  
  	if (!TAILQ_EMPTY(&asoc->reasmqueue)) {
  		/* now lets kick out and check for more fragmented delivery */
                  /*sa_ignore NO_NULL_CHK*/
  		sctp_deliver_reasm_check(stcb, &stcb->asoc);
  	}
  }
  