xref: /freebsd/sys/netinet/sctp_indata.c (revision 0efd6615cd5f39b67cec82a7034e655f3b5801e3)
1 /*-
2  * Copyright (c) 2001-2006, Cisco Systems, Inc. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions are met:
6  *
7  * a) Redistributions of source code must retain the above copyright notice,
8  *   this list of conditions and the following disclaimer.
9  *
10  * b) Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in
12  *   the documentation and/or other materials provided with the distribution.
13  *
14  * c) Neither the name of Cisco Systems, Inc. nor the names of its
15  *    contributors may be used to endorse or promote products derived
16  *    from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
20  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
28  * THE POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 /* $KAME: sctp_indata.c,v 1.36 2005/03/06 16:04:17 itojun Exp $	 */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 
37 #include "opt_ipsec.h"
38 #include "opt_inet6.h"
39 #include "opt_inet.h"
40 
41 #include "opt_sctp.h"
42 
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/mbuf.h>
46 #include <sys/malloc.h>
47 #include <sys/socket.h>
48 #include <sys/socketvar.h>
49 #include <sys/sysctl.h>
50 
51 #include <net/if.h>
52 #include <net/route.h>
53 
54 
55 #include <sys/limits.h>
56 #include <machine/cpu.h>
57 
58 #include <netinet/in.h>
59 #include <netinet/in_systm.h>
60 #include <netinet/ip.h>
61 #ifdef INET6
62 #include <netinet/ip6.h>
63 #endif				/* INET6 */
64 #include <netinet/in_pcb.h>
65 #include <netinet/in_var.h>
66 #include <netinet/ip_var.h>
67 #ifdef INET6
68 #include <netinet6/ip6_var.h>
69 #endif				/* INET6 */
70 #include <netinet/ip_icmp.h>
71 #include <netinet/icmp_var.h>
72 
73 #include <netinet/sctp_os.h>
74 #include <netinet/sctp_var.h>
75 #include <netinet/sctp_pcb.h>
76 #include <netinet/sctp_header.h>
77 #include <netinet/sctputil.h>
78 #include <netinet/sctp_output.h>
79 #include <netinet/sctp_input.h>
80 #include <netinet/sctp_indata.h>
81 #include <netinet/sctp_uio.h>
82 #include <netinet/sctp_timer.h>
83 #ifdef IPSEC
84 #include <netinet6/ipsec.h>
85 #include <netkey/key.h>
86 #endif				/* IPSEC */
87 
88 
89 #ifdef SCTP_DEBUG
90 extern uint32_t sctp_debug_on;
91 
92 #endif
93 
94 /*
95  * NOTES: On the outbound side of things I need to check the sack timer to
96  * see if I should generate a sack into the chunk queue (if I have data to
97  * send that is and will be sending it .. for bundling.
98  *
99  * The callback in sctp_usrreq.c will get called when the socket is read from.
100  * This will cause sctp_service_queues() to get called on the top entry in
101  * the list.
102  */
103 
104 extern int sctp_strict_sacks;
105 
106 __inline void
107 sctp_set_rwnd(struct sctp_tcb *stcb, struct sctp_association *asoc)
108 {
109 	uint32_t calc, calc_w_oh;
110 
111 	/*
112 	 * This is really set wrong with respect to a 1-2-m socket. Since
113 	 * the sb_cc is the count that everyone as put up. When we re-write
114 	 * sctp_soreceive then we will fix this so that ONLY this
115 	 * associations data is taken into account.
116 	 */
117 	if (stcb->sctp_socket == NULL)
118 		return;
119 
120 	if (stcb->asoc.sb_cc == 0 &&
121 	    asoc->size_on_reasm_queue == 0 &&
122 	    asoc->size_on_all_streams == 0) {
123 		/* Full rwnd granted */
124 		asoc->my_rwnd = max(stcb->sctp_socket->so_rcv.sb_hiwat,
125 		    SCTP_MINIMAL_RWND);
126 		return;
127 	}
128 	/* get actual space */
129 	calc = (uint32_t) sctp_sbspace(&stcb->asoc, &stcb->sctp_socket->so_rcv);
130 
131 	/*
132 	 * take out what has NOT been put on socket queue and we yet hold
133 	 * for putting up.
134 	 */
135 	calc = sctp_sbspace_sub(calc, (uint32_t) asoc->size_on_reasm_queue);
136 	calc = sctp_sbspace_sub(calc, (uint32_t) asoc->size_on_all_streams);
137 
138 	if (calc == 0) {
139 		/* out of space */
140 		asoc->my_rwnd = 0;
141 		return;
142 	}
143 	/* what is the overhead of all these rwnd's */
144 	calc_w_oh = sctp_sbspace_sub(calc, stcb->asoc.my_rwnd_control_len);
145 	asoc->my_rwnd = calc;
146 	if (calc_w_oh == 0) {
147 		/*
148 		 * If our overhead is greater than the advertised rwnd, we
149 		 * clamp the rwnd to 1. This lets us still accept inbound
150 		 * segments, but hopefully will shut the sender down when he
151 		 * finally gets the message.
152 		 */
153 		asoc->my_rwnd = 1;
154 	} else {
155 		/* SWS threshold */
156 		if (asoc->my_rwnd &&
157 		    (asoc->my_rwnd < stcb->sctp_ep->sctp_ep.sctp_sws_receiver)) {
158 			/* SWS engaged, tell peer none left */
159 			asoc->my_rwnd = 1;
160 		}
161 	}
162 }
163 
164 /* Calculate what the rwnd would be */
165 
166 __inline uint32_t
167 sctp_calc_rwnd(struct sctp_tcb *stcb, struct sctp_association *asoc)
168 {
169 	uint32_t calc = 0, calc_w_oh;
170 
171 	/*
172 	 * This is really set wrong with respect to a 1-2-m socket. Since
173 	 * the sb_cc is the count that everyone as put up. When we re-write
174 	 * sctp_soreceive then we will fix this so that ONLY this
175 	 * associations data is taken into account.
176 	 */
177 	if (stcb->sctp_socket == NULL)
178 		return (calc);
179 
180 	if (stcb->asoc.sb_cc == 0 &&
181 	    asoc->size_on_reasm_queue == 0 &&
182 	    asoc->size_on_all_streams == 0) {
183 		/* Full rwnd granted */
184 		calc = max(stcb->sctp_socket->so_rcv.sb_hiwat,
185 		    SCTP_MINIMAL_RWND);
186 		return (calc);
187 	}
188 	/* get actual space */
189 	calc = (uint32_t) sctp_sbspace(&stcb->asoc, &stcb->sctp_socket->so_rcv);
190 
191 	/*
192 	 * take out what has NOT been put on socket queue and we yet hold
193 	 * for putting up.
194 	 */
195 	calc = sctp_sbspace_sub(calc, (uint32_t) asoc->size_on_reasm_queue);
196 	calc = sctp_sbspace_sub(calc, (uint32_t) asoc->size_on_all_streams);
197 
198 	if (calc == 0) {
199 		/* out of space */
200 		return (calc);
201 	}
202 	/* what is the overhead of all these rwnd's */
203 	calc_w_oh = sctp_sbspace_sub(calc, stcb->asoc.my_rwnd_control_len);
204 	if (calc_w_oh == 0) {
205 		/*
206 		 * If our overhead is greater than the advertised rwnd, we
207 		 * clamp the rwnd to 1. This lets us still accept inbound
208 		 * segments, but hopefully will shut the sender down when he
209 		 * finally gets the message.
210 		 */
211 		calc = 1;
212 	} else {
213 		/* SWS threshold */
214 		if (calc &&
215 		    (calc < stcb->sctp_ep->sctp_ep.sctp_sws_receiver)) {
216 			/* SWS engaged, tell peer none left */
217 			calc = 1;
218 		}
219 	}
220 	return (calc);
221 }
222 
223 
224 
225 /*
226  * Build out our readq entry based on the incoming packet.
227  */
228 struct sctp_queued_to_read *
229 sctp_build_readq_entry(struct sctp_tcb *stcb,
230     struct sctp_nets *net,
231     uint32_t tsn, uint32_t ppid,
232     uint32_t context, uint16_t stream_no,
233     uint16_t stream_seq, uint8_t flags,
234     struct mbuf *dm)
235 {
236 	struct sctp_queued_to_read *read_queue_e = NULL;
237 
238 	sctp_alloc_a_readq(stcb, read_queue_e);
239 	if (read_queue_e == NULL) {
240 		goto failed_build;
241 	}
242 	read_queue_e->sinfo_stream = stream_no;
243 	read_queue_e->sinfo_ssn = stream_seq;
244 	read_queue_e->sinfo_flags = (flags << 8);
245 	read_queue_e->sinfo_ppid = ppid;
246 	read_queue_e->sinfo_context = stcb->asoc.context;
247 	read_queue_e->sinfo_timetolive = 0;
248 	read_queue_e->sinfo_tsn = tsn;
249 	read_queue_e->sinfo_cumtsn = tsn;
250 	read_queue_e->sinfo_assoc_id = sctp_get_associd(stcb);
251 	read_queue_e->whoFrom = net;
252 	read_queue_e->length = 0;
253 	atomic_add_int(&net->ref_count, 1);
254 	read_queue_e->data = dm;
255 	read_queue_e->tail_mbuf = NULL;
256 	read_queue_e->stcb = stcb;
257 	read_queue_e->port_from = stcb->rport;
258 	read_queue_e->do_not_ref_stcb = 0;
259 	read_queue_e->end_added = 0;
260 	read_queue_e->pdapi_aborted = 0;
261 failed_build:
262 	return (read_queue_e);
263 }
264 
265 
266 /*
267  * Build out our readq entry based on the incoming packet.
268  */
269 static struct sctp_queued_to_read *
270 sctp_build_readq_entry_chk(struct sctp_tcb *stcb,
271     struct sctp_tmit_chunk *chk)
272 {
273 	struct sctp_queued_to_read *read_queue_e = NULL;
274 
275 	sctp_alloc_a_readq(stcb, read_queue_e);
276 	if (read_queue_e == NULL) {
277 		goto failed_build;
278 	}
279 	read_queue_e->sinfo_stream = chk->rec.data.stream_number;
280 	read_queue_e->sinfo_ssn = chk->rec.data.stream_seq;
281 	read_queue_e->sinfo_flags = (chk->rec.data.rcv_flags << 8);
282 	read_queue_e->sinfo_ppid = chk->rec.data.payloadtype;
283 	read_queue_e->sinfo_context = stcb->asoc.context;
284 	read_queue_e->sinfo_timetolive = 0;
285 	read_queue_e->sinfo_tsn = chk->rec.data.TSN_seq;
286 	read_queue_e->sinfo_cumtsn = chk->rec.data.TSN_seq;
287 	read_queue_e->sinfo_assoc_id = sctp_get_associd(stcb);
288 	read_queue_e->whoFrom = chk->whoTo;
289 	read_queue_e->length = 0;
290 	atomic_add_int(&chk->whoTo->ref_count, 1);
291 	read_queue_e->data = chk->data;
292 	read_queue_e->tail_mbuf = NULL;
293 	read_queue_e->stcb = stcb;
294 	read_queue_e->port_from = stcb->rport;
295 	read_queue_e->do_not_ref_stcb = 0;
296 	read_queue_e->end_added = 0;
297 	read_queue_e->pdapi_aborted = 0;
298 failed_build:
299 	return (read_queue_e);
300 }
301 
302 
303 struct mbuf *
304 sctp_build_ctl_nchunk(struct sctp_inpcb *inp,
305     struct sctp_sndrcvinfo *sinfo)
306 {
307 	struct sctp_sndrcvinfo *outinfo;
308 	struct cmsghdr *cmh;
309 	struct mbuf *ret;
310 	int len;
311 	int use_extended = 0;
312 
313 	if (sctp_is_feature_off(inp, SCTP_PCB_FLAGS_RECVDATAIOEVNT)) {
314 		/* user does not want the sndrcv ctl */
315 		return (NULL);
316 	}
317 	if (sctp_is_feature_on(inp, SCTP_PCB_FLAGS_EXT_RCVINFO)) {
318 		use_extended = 1;
319 		len = CMSG_LEN(sizeof(struct sctp_extrcvinfo));
320 	} else {
321 		len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo));
322 	}
323 
324 
325 	ret = sctp_get_mbuf_for_msg(len,
326 	    1, M_DONTWAIT, 1, MT_DATA);
327 
328 	if (ret == NULL) {
329 		/* No space */
330 		return (ret);
331 	}
332 	/* We need a CMSG header followed by the struct  */
333 	cmh = mtod(ret, struct cmsghdr *);
334 	outinfo = (struct sctp_sndrcvinfo *)CMSG_DATA(cmh);
335 	cmh->cmsg_level = IPPROTO_SCTP;
336 	if (use_extended) {
337 		cmh->cmsg_type = SCTP_EXTRCV;
338 		cmh->cmsg_len = len;
339 		memcpy(outinfo, sinfo, len);
340 	} else {
341 		cmh->cmsg_type = SCTP_SNDRCV;
342 		cmh->cmsg_len = len;
343 		*outinfo = *sinfo;
344 	}
345 	ret->m_len = cmh->cmsg_len;
346 	ret->m_pkthdr.len = ret->m_len;
347 	return (ret);
348 }
349 
350 /*
351  * We are delivering currently from the reassembly queue. We must continue to
352  * deliver until we either: 1) run out of space. 2) run out of sequential
353  * TSN's 3) hit the SCTP_DATA_LAST_FRAG flag.
354  */
355 static void
356 sctp_service_reassembly(struct sctp_tcb *stcb, struct sctp_association *asoc)
357 {
358 	struct sctp_tmit_chunk *chk;
359 	struct mbuf *m;
360 	uint16_t nxt_todel;
361 	uint16_t stream_no;
362 	int end = 0;
363 	int cntDel;
364 
365 	cntDel = stream_no = 0;
366 	struct sctp_queued_to_read *control, *ctl, *ctlat;
367 
368 	if (stcb && ((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) ||
369 	    (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET))
370 	    ) {
371 		/* socket above is long gone */
372 		asoc->fragmented_delivery_inprogress = 0;
373 		chk = TAILQ_FIRST(&asoc->reasmqueue);
374 		while (chk) {
375 			TAILQ_REMOVE(&asoc->reasmqueue, chk, sctp_next);
376 			asoc->size_on_reasm_queue -= chk->send_size;
377 			sctp_ucount_decr(asoc->cnt_on_reasm_queue);
378 			/*
379 			 * Lose the data pointer, since its in the socket
380 			 * buffer
381 			 */
382 			if (chk->data) {
383 				sctp_m_freem(chk->data);
384 				chk->data = NULL;
385 			}
386 			/* Now free the address and data */
387 			sctp_free_remote_addr(chk->whoTo);
388 			sctp_free_a_chunk(stcb, chk);
389 			chk = TAILQ_FIRST(&asoc->reasmqueue);
390 		}
391 		return;
392 	}
393 	SCTP_TCB_LOCK_ASSERT(stcb);
394 	do {
395 		chk = TAILQ_FIRST(&asoc->reasmqueue);
396 		if (chk == NULL) {
397 			return;
398 		}
399 		if (chk->rec.data.TSN_seq != (asoc->tsn_last_delivered + 1)) {
400 			/* Can't deliver more :< */
401 			return;
402 		}
403 		stream_no = chk->rec.data.stream_number;
404 		nxt_todel = asoc->strmin[stream_no].last_sequence_delivered + 1;
405 		if (nxt_todel != chk->rec.data.stream_seq &&
406 		    (chk->rec.data.rcv_flags & SCTP_DATA_UNORDERED) == 0) {
407 			/*
408 			 * Not the next sequence to deliver in its stream OR
409 			 * unordered
410 			 */
411 			return;
412 		}
413 		if ((chk->data->m_flags & M_PKTHDR) == 0) {
414 			m = sctp_get_mbuf_for_msg(1,
415 			    1, M_DONTWAIT, 1, MT_DATA);
416 			if (m == NULL) {
417 				/* no room! */
418 				return;
419 			}
420 			m->m_pkthdr.len = chk->send_size;
421 			m->m_len = 0;
422 			m->m_next = chk->data;
423 			chk->data = m;
424 		}
425 		if (chk->rec.data.rcv_flags & SCTP_DATA_LAST_FRAG) {
426 			if (chk->data->m_next == NULL) {
427 				/* hopefully we hit here most of the time */
428 				chk->data->m_flags |= M_EOR;
429 			} else {
430 				/*
431 				 * Add the flag to the LAST mbuf in the
432 				 * chain
433 				 */
434 				m = chk->data;
435 				while (m->m_next != NULL) {
436 					m = m->m_next;
437 				}
438 				m->m_flags |= M_EOR;
439 			}
440 		}
441 		if (chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) {
442 
443 			control = sctp_build_readq_entry_chk(stcb, chk);
444 			if (control == NULL) {
445 				/* out of memory? */
446 				return;
447 			}
448 			/* save it off for our future deliveries */
449 			stcb->asoc.control_pdapi = control;
450 			if (chk->rec.data.rcv_flags & SCTP_DATA_LAST_FRAG)
451 				end = 1;
452 			else
453 				end = 0;
454 			sctp_add_to_readq(stcb->sctp_ep,
455 			    stcb, control, &stcb->sctp_socket->so_rcv, end);
456 			cntDel++;
457 		} else {
458 			if (chk->rec.data.rcv_flags & SCTP_DATA_LAST_FRAG)
459 				end = 1;
460 			else
461 				end = 0;
462 			if (sctp_append_to_readq(stcb->sctp_ep, stcb,
463 			    stcb->asoc.control_pdapi,
464 			    chk->data, end, chk->rec.data.TSN_seq,
465 			    &stcb->sctp_socket->so_rcv)) {
466 				/*
467 				 * something is very wrong, either
468 				 * control_pdapi is NULL, or the tail_mbuf
469 				 * is corrupt, or there is a EOM already on
470 				 * the mbuf chain.
471 				 */
472 				if (stcb->asoc.control_pdapi == NULL) {
473 					panic("This should not happen control_pdapi NULL?");
474 				}
475 				if (stcb->asoc.control_pdapi->tail_mbuf == NULL) {
476 					panic("This should not happen, tail_mbuf not being maintained?");
477 				}
478 				/* if we did not panic, it was a EOM */
479 				panic("Bad chunking ??");
480 			}
481 			cntDel++;
482 		}
483 		/* pull it we did it */
484 		TAILQ_REMOVE(&asoc->reasmqueue, chk, sctp_next);
485 		if (chk->rec.data.rcv_flags & SCTP_DATA_LAST_FRAG) {
486 			asoc->fragmented_delivery_inprogress = 0;
487 			if ((chk->rec.data.rcv_flags & SCTP_DATA_UNORDERED) == 0) {
488 				asoc->strmin[stream_no].last_sequence_delivered++;
489 			}
490 			if ((chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) == 0) {
491 				SCTP_STAT_INCR_COUNTER64(sctps_reasmusrmsgs);
492 			}
493 		} else if (chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) {
494 			/*
495 			 * turn the flag back on since we just  delivered
496 			 * yet another one.
497 			 */
498 			asoc->fragmented_delivery_inprogress = 1;
499 		}
500 		asoc->tsn_of_pdapi_last_delivered = chk->rec.data.TSN_seq;
501 		asoc->last_flags_delivered = chk->rec.data.rcv_flags;
502 		asoc->last_strm_seq_delivered = chk->rec.data.stream_seq;
503 		asoc->last_strm_no_delivered = chk->rec.data.stream_number;
504 
505 		asoc->tsn_last_delivered = chk->rec.data.TSN_seq;
506 		asoc->size_on_reasm_queue -= chk->send_size;
507 		sctp_ucount_decr(asoc->cnt_on_reasm_queue);
508 		/* free up the chk */
509 		chk->data = NULL;
510 		sctp_free_remote_addr(chk->whoTo);
511 		sctp_free_a_chunk(stcb, chk);
512 
513 		if (asoc->fragmented_delivery_inprogress == 0) {
514 			/*
515 			 * Now lets see if we can deliver the next one on
516 			 * the stream
517 			 */
518 			uint16_t nxt_todel;
519 			struct sctp_stream_in *strm;
520 
521 			strm = &asoc->strmin[stream_no];
522 			nxt_todel = strm->last_sequence_delivered + 1;
523 			ctl = TAILQ_FIRST(&strm->inqueue);
524 			if (ctl && (nxt_todel == ctl->sinfo_ssn)) {
525 				while (ctl != NULL) {
526 					/* Deliver more if we can. */
527 					if (nxt_todel == ctl->sinfo_ssn) {
528 						ctlat = TAILQ_NEXT(ctl, next);
529 						TAILQ_REMOVE(&strm->inqueue, ctl, next);
530 						asoc->size_on_all_streams -= ctl->length;
531 						sctp_ucount_decr(asoc->cnt_on_all_streams);
532 						strm->last_sequence_delivered++;
533 						sctp_add_to_readq(stcb->sctp_ep, stcb,
534 						    ctl,
535 						    &stcb->sctp_socket->so_rcv, 1);
536 						ctl = ctlat;
537 					} else {
538 						break;
539 					}
540 					nxt_todel = strm->last_sequence_delivered + 1;
541 				}
542 			}
543 			return;
544 		}
545 		chk = TAILQ_FIRST(&asoc->reasmqueue);
546 	} while (chk);
547 }
548 
549 /*
550  * Queue the chunk either right into the socket buffer if it is the next one
551  * to go OR put it in the correct place in the delivery queue.  If we do
552  * append to the so_buf, keep doing so until we are out of order. One big
553  * question still remains, what to do when the socket buffer is FULL??
554  */
555 static void
556 sctp_queue_data_to_stream(struct sctp_tcb *stcb, struct sctp_association *asoc,
557     struct sctp_queued_to_read *control, int *abort_flag)
558 {
559 	/*
560 	 * FIX-ME maybe? What happens when the ssn wraps? If we are getting
561 	 * all the data in one stream this could happen quite rapidly. One
562 	 * could use the TSN to keep track of things, but this scheme breaks
563 	 * down in the other type of stream useage that could occur. Send a
564 	 * single msg to stream 0, send 4Billion messages to stream 1, now
565 	 * send a message to stream 0. You have a situation where the TSN
566 	 * has wrapped but not in the stream. Is this worth worrying about
567 	 * or should we just change our queue sort at the bottom to be by
568 	 * TSN.
569 	 *
570 	 * Could it also be legal for a peer to send ssn 1 with TSN 2 and ssn 2
571 	 * with TSN 1? If the peer is doing some sort of funky TSN/SSN
572 	 * assignment this could happen... and I don't see how this would be
573 	 * a violation. So for now I am undecided an will leave the sort by
574 	 * SSN alone. Maybe a hybred approach is the answer
575 	 *
576 	 */
577 	struct sctp_stream_in *strm;
578 	struct sctp_queued_to_read *at;
579 	int queue_needed;
580 	uint16_t nxt_todel;
581 	struct mbuf *oper;
582 
583 	queue_needed = 1;
584 	asoc->size_on_all_streams += control->length;
585 	sctp_ucount_incr(asoc->cnt_on_all_streams);
586 	strm = &asoc->strmin[control->sinfo_stream];
587 	nxt_todel = strm->last_sequence_delivered + 1;
588 #ifdef SCTP_STR_LOGGING
589 	sctp_log_strm_del(control, NULL, SCTP_STR_LOG_FROM_INTO_STRD);
590 #endif
591 #ifdef SCTP_DEBUG
592 	if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
593 		printf("queue to stream called for ssn:%u lastdel:%u nxt:%u\n",
594 		    (uint32_t) control->sinfo_stream,
595 		    (uint32_t) strm->last_sequence_delivered, (uint32_t) nxt_todel);
596 	}
597 #endif
598 	if (compare_with_wrap(strm->last_sequence_delivered,
599 	    control->sinfo_ssn, MAX_SEQ) ||
600 	    (strm->last_sequence_delivered == control->sinfo_ssn)) {
601 		/* The incoming sseq is behind where we last delivered? */
602 #ifdef SCTP_DEBUG
603 		if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
604 			printf("Duplicate S-SEQ:%d delivered:%d from peer, Abort  association\n",
605 			    control->sinfo_ssn,
606 			    strm->last_sequence_delivered);
607 		}
608 #endif
609 		/*
610 		 * throw it in the stream so it gets cleaned up in
611 		 * association destruction
612 		 */
613 		TAILQ_INSERT_HEAD(&strm->inqueue, control, next);
614 		oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
615 		    0, M_DONTWAIT, 1, MT_DATA);
616 		if (oper) {
617 			struct sctp_paramhdr *ph;
618 			uint32_t *ippp;
619 
620 			oper->m_len = sizeof(struct sctp_paramhdr) +
621 			    (sizeof(uint32_t) * 3);
622 			ph = mtod(oper, struct sctp_paramhdr *);
623 			ph->param_type = htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
624 			ph->param_length = htons(oper->m_len);
625 			ippp = (uint32_t *) (ph + 1);
626 			*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_1);
627 			ippp++;
628 			*ippp = control->sinfo_tsn;
629 			ippp++;
630 			*ippp = ((control->sinfo_stream << 16) | control->sinfo_ssn);
631 		}
632 		stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_1;
633 		sctp_abort_an_association(stcb->sctp_ep, stcb,
634 		    SCTP_PEER_FAULTY, oper);
635 
636 		*abort_flag = 1;
637 		return;
638 
639 	}
640 	if (nxt_todel == control->sinfo_ssn) {
641 		/* can be delivered right away? */
642 #ifdef SCTP_STR_LOGGING
643 		sctp_log_strm_del(control, NULL, SCTP_STR_LOG_FROM_IMMED_DEL);
644 #endif
645 		queue_needed = 0;
646 		asoc->size_on_all_streams -= control->length;
647 		sctp_ucount_decr(asoc->cnt_on_all_streams);
648 		strm->last_sequence_delivered++;
649 		sctp_add_to_readq(stcb->sctp_ep, stcb,
650 		    control,
651 		    &stcb->sctp_socket->so_rcv, 1);
652 		control = TAILQ_FIRST(&strm->inqueue);
653 		while (control != NULL) {
654 			/* all delivered */
655 			nxt_todel = strm->last_sequence_delivered + 1;
656 			if (nxt_todel == control->sinfo_ssn) {
657 				at = TAILQ_NEXT(control, next);
658 				TAILQ_REMOVE(&strm->inqueue, control, next);
659 				asoc->size_on_all_streams -= control->length;
660 				sctp_ucount_decr(asoc->cnt_on_all_streams);
661 				strm->last_sequence_delivered++;
662 				/*
663 				 * We ignore the return of deliver_data here
664 				 * since we always can hold the chunk on the
665 				 * d-queue. And we have a finite number that
666 				 * can be delivered from the strq.
667 				 */
668 #ifdef SCTP_STR_LOGGING
669 				sctp_log_strm_del(control, NULL,
670 				    SCTP_STR_LOG_FROM_IMMED_DEL);
671 #endif
672 				sctp_add_to_readq(stcb->sctp_ep, stcb,
673 				    control,
674 				    &stcb->sctp_socket->so_rcv, 1);
675 				control = at;
676 				continue;
677 			}
678 			break;
679 		}
680 	}
681 	if (queue_needed) {
682 		/*
683 		 * Ok, we did not deliver this guy, find the correct place
684 		 * to put it on the queue.
685 		 */
686 		if (TAILQ_EMPTY(&strm->inqueue)) {
687 			/* Empty queue */
688 #ifdef SCTP_STR_LOGGING
689 			sctp_log_strm_del(control, NULL, SCTP_STR_LOG_FROM_INSERT_HD);
690 #endif
691 			TAILQ_INSERT_HEAD(&strm->inqueue, control, next);
692 		} else {
693 			TAILQ_FOREACH(at, &strm->inqueue, next) {
694 				if (compare_with_wrap(at->sinfo_ssn,
695 				    control->sinfo_ssn, MAX_SEQ)) {
696 					/*
697 					 * one in queue is bigger than the
698 					 * new one, insert before this one
699 					 */
700 #ifdef SCTP_STR_LOGGING
701 					sctp_log_strm_del(control, at,
702 					    SCTP_STR_LOG_FROM_INSERT_MD);
703 #endif
704 					TAILQ_INSERT_BEFORE(at, control, next);
705 					break;
706 				} else if (at->sinfo_ssn == control->sinfo_ssn) {
707 					/*
708 					 * Gak, He sent me a duplicate str
709 					 * seq number
710 					 */
711 					/*
712 					 * foo bar, I guess I will just free
713 					 * this new guy, should we abort
714 					 * too? FIX ME MAYBE? Or it COULD be
715 					 * that the SSN's have wrapped.
716 					 * Maybe I should compare to TSN
717 					 * somehow... sigh for now just blow
718 					 * away the chunk!
719 					 */
720 
721 					if (control->data)
722 						sctp_m_freem(control->data);
723 					control->data = NULL;
724 					asoc->size_on_all_streams -= control->length;
725 					sctp_ucount_decr(asoc->cnt_on_all_streams);
726 					sctp_free_remote_addr(control->whoFrom);
727 					sctp_free_a_readq(stcb, control);
728 					return;
729 				} else {
730 					if (TAILQ_NEXT(at, next) == NULL) {
731 						/*
732 						 * We are at the end, insert
733 						 * it after this one
734 						 */
735 #ifdef SCTP_STR_LOGGING
736 						sctp_log_strm_del(control, at,
737 						    SCTP_STR_LOG_FROM_INSERT_TL);
738 #endif
739 						TAILQ_INSERT_AFTER(&strm->inqueue,
740 						    at, control, next);
741 						break;
742 					}
743 				}
744 			}
745 		}
746 	}
747 }
748 
749 /*
750  * Returns two things: You get the total size of the deliverable parts of the
751  * first fragmented message on the reassembly queue. And you get a 1 back if
752  * all of the message is ready or a 0 back if the message is still incomplete
753  */
754 static int
755 sctp_is_all_msg_on_reasm(struct sctp_association *asoc, uint32_t * t_size)
756 {
757 	struct sctp_tmit_chunk *chk;
758 	uint32_t tsn;
759 
760 	*t_size = 0;
761 	chk = TAILQ_FIRST(&asoc->reasmqueue);
762 	if (chk == NULL) {
763 		/* nothing on the queue */
764 		return (0);
765 	}
766 	if ((chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) == 0) {
767 		/* Not a first on the queue */
768 		return (0);
769 	}
770 	tsn = chk->rec.data.TSN_seq;
771 	while (chk) {
772 		if (tsn != chk->rec.data.TSN_seq) {
773 			return (0);
774 		}
775 		*t_size += chk->send_size;
776 		if (chk->rec.data.rcv_flags & SCTP_DATA_LAST_FRAG) {
777 			return (1);
778 		}
779 		tsn++;
780 		chk = TAILQ_NEXT(chk, sctp_next);
781 	}
782 	return (0);
783 }
784 
785 static void
786 sctp_deliver_reasm_check(struct sctp_tcb *stcb, struct sctp_association *asoc)
787 {
788 	struct sctp_tmit_chunk *chk;
789 	uint16_t nxt_todel;
790 	uint32_t tsize;
791 
792 	chk = TAILQ_FIRST(&asoc->reasmqueue);
793 	if (chk == NULL) {
794 		/* Huh? */
795 		asoc->size_on_reasm_queue = 0;
796 		asoc->cnt_on_reasm_queue = 0;
797 		return;
798 	}
799 	if (asoc->fragmented_delivery_inprogress == 0) {
800 		nxt_todel =
801 		    asoc->strmin[chk->rec.data.stream_number].last_sequence_delivered + 1;
802 		if ((chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) &&
803 		    (nxt_todel == chk->rec.data.stream_seq ||
804 		    (chk->rec.data.rcv_flags & SCTP_DATA_UNORDERED))) {
805 			/*
806 			 * Yep the first one is here and its ok to deliver
807 			 * but should we?
808 			 */
809 			if ((sctp_is_all_msg_on_reasm(asoc, &tsize) ||
810 			    (tsize > stcb->sctp_ep->partial_delivery_point))) {
811 
812 				/*
813 				 * Yes, we setup to start reception, by
814 				 * backing down the TSN just in case we
815 				 * can't deliver. If we
816 				 */
817 				asoc->fragmented_delivery_inprogress = 1;
818 				asoc->tsn_last_delivered =
819 				    chk->rec.data.TSN_seq - 1;
820 				asoc->str_of_pdapi =
821 				    chk->rec.data.stream_number;
822 				asoc->ssn_of_pdapi = chk->rec.data.stream_seq;
823 				asoc->pdapi_ppid = chk->rec.data.payloadtype;
824 				asoc->fragment_flags = chk->rec.data.rcv_flags;
825 				sctp_service_reassembly(stcb, asoc);
826 			}
827 		}
828 	} else {
829 		sctp_service_reassembly(stcb, asoc);
830 	}
831 }
832 
833 /*
834  * Dump onto the re-assembly queue, in its proper place. After dumping on the
835  * queue, see if anthing can be delivered. If so pull it off (or as much as
836  * we can. If we run out of space then we must dump what we can and set the
837  * appropriate flag to say we queued what we could.
838  */
839 static void
840 sctp_queue_data_for_reasm(struct sctp_tcb *stcb, struct sctp_association *asoc,
841     struct sctp_tmit_chunk *chk, int *abort_flag)
842 {
843 	struct mbuf *oper;
844 	uint32_t cum_ackp1, last_tsn, prev_tsn, post_tsn;
845 	u_char last_flags;
846 	struct sctp_tmit_chunk *at, *prev, *next;
847 
848 	prev = next = NULL;
849 	cum_ackp1 = asoc->tsn_last_delivered + 1;
850 	if (TAILQ_EMPTY(&asoc->reasmqueue)) {
851 		/* This is the first one on the queue */
852 		TAILQ_INSERT_HEAD(&asoc->reasmqueue, chk, sctp_next);
853 		/*
854 		 * we do not check for delivery of anything when only one
855 		 * fragment is here
856 		 */
857 		asoc->size_on_reasm_queue = chk->send_size;
858 		sctp_ucount_incr(asoc->cnt_on_reasm_queue);
859 		if (chk->rec.data.TSN_seq == cum_ackp1) {
860 			if (asoc->fragmented_delivery_inprogress == 0 &&
861 			    (chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) !=
862 			    SCTP_DATA_FIRST_FRAG) {
863 				/*
864 				 * An empty queue, no delivery inprogress,
865 				 * we hit the next one and it does NOT have
866 				 * a FIRST fragment mark.
867 				 */
868 #ifdef SCTP_DEBUG
869 				if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
870 					printf("Gak, Evil plot, its not first, no fragmented delivery in progress\n");
871 				}
872 #endif
873 				oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
874 				    0, M_DONTWAIT, 1, MT_DATA);
875 
876 				if (oper) {
877 					struct sctp_paramhdr *ph;
878 					uint32_t *ippp;
879 
880 					oper->m_len =
881 					    sizeof(struct sctp_paramhdr) +
882 					    (sizeof(uint32_t) * 3);
883 					ph = mtod(oper, struct sctp_paramhdr *);
884 					ph->param_type =
885 					    htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
886 					ph->param_length = htons(oper->m_len);
887 					ippp = (uint32_t *) (ph + 1);
888 					*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_2);
889 					ippp++;
890 					*ippp = chk->rec.data.TSN_seq;
891 					ippp++;
892 					*ippp = ((chk->rec.data.stream_number << 16) | chk->rec.data.stream_seq);
893 
894 				}
895 				stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_2;
896 				sctp_abort_an_association(stcb->sctp_ep, stcb,
897 				    SCTP_PEER_FAULTY, oper);
898 				*abort_flag = 1;
899 			} else if (asoc->fragmented_delivery_inprogress &&
900 			    (chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) == SCTP_DATA_FIRST_FRAG) {
901 				/*
902 				 * We are doing a partial delivery and the
903 				 * NEXT chunk MUST be either the LAST or
904 				 * MIDDLE fragment NOT a FIRST
905 				 */
906 #ifdef SCTP_DEBUG
907 				if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
908 					printf("Gak, Evil plot, it IS a first and fragmented delivery in progress\n");
909 				}
910 #endif
911 				oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
912 				    0, M_DONTWAIT, 1, MT_DATA);
913 				if (oper) {
914 					struct sctp_paramhdr *ph;
915 					uint32_t *ippp;
916 
917 					oper->m_len =
918 					    sizeof(struct sctp_paramhdr) +
919 					    (3 * sizeof(uint32_t));
920 					ph = mtod(oper, struct sctp_paramhdr *);
921 					ph->param_type =
922 					    htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
923 					ph->param_length = htons(oper->m_len);
924 					ippp = (uint32_t *) (ph + 1);
925 					*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_3);
926 					ippp++;
927 					*ippp = chk->rec.data.TSN_seq;
928 					ippp++;
929 					*ippp = ((chk->rec.data.stream_number << 16) | chk->rec.data.stream_seq);
930 				}
931 				stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_3;
932 				sctp_abort_an_association(stcb->sctp_ep, stcb,
933 				    SCTP_PEER_FAULTY, oper);
934 				*abort_flag = 1;
935 			} else if (asoc->fragmented_delivery_inprogress) {
936 				/*
937 				 * Here we are ok with a MIDDLE or LAST
938 				 * piece
939 				 */
940 				if (chk->rec.data.stream_number !=
941 				    asoc->str_of_pdapi) {
942 					/* Got to be the right STR No */
943 #ifdef SCTP_DEBUG
944 					if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
945 						printf("Gak, Evil plot, it IS not same stream number %d vs %d\n",
946 						    chk->rec.data.stream_number,
947 						    asoc->str_of_pdapi);
948 					}
949 #endif
950 					oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
951 					    0, M_DONTWAIT, 1, MT_DATA);
952 					if (oper) {
953 						struct sctp_paramhdr *ph;
954 						uint32_t *ippp;
955 
956 						oper->m_len =
957 						    sizeof(struct sctp_paramhdr) +
958 						    (sizeof(uint32_t) * 3);
959 						ph = mtod(oper,
960 						    struct sctp_paramhdr *);
961 						ph->param_type =
962 						    htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
963 						ph->param_length =
964 						    htons(oper->m_len);
965 						ippp = (uint32_t *) (ph + 1);
966 						*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_4);
967 						ippp++;
968 						*ippp = chk->rec.data.TSN_seq;
969 						ippp++;
970 						*ippp = ((chk->rec.data.stream_number << 16) | chk->rec.data.stream_seq);
971 					}
972 					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_4;
973 					sctp_abort_an_association(stcb->sctp_ep,
974 					    stcb, SCTP_PEER_FAULTY, oper);
975 					*abort_flag = 1;
976 				} else if ((asoc->fragment_flags & SCTP_DATA_UNORDERED) !=
977 					    SCTP_DATA_UNORDERED &&
978 					    chk->rec.data.stream_seq !=
979 				    asoc->ssn_of_pdapi) {
980 					/* Got to be the right STR Seq */
981 #ifdef SCTP_DEBUG
982 					if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
983 						printf("Gak, Evil plot, it IS not same stream seq %d vs %d\n",
984 						    chk->rec.data.stream_seq,
985 						    asoc->ssn_of_pdapi);
986 					}
987 #endif
988 					oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
989 					    0, M_DONTWAIT, 1, MT_DATA);
990 					if (oper) {
991 						struct sctp_paramhdr *ph;
992 						uint32_t *ippp;
993 
994 						oper->m_len =
995 						    sizeof(struct sctp_paramhdr) +
996 						    (3 * sizeof(uint32_t));
997 						ph = mtod(oper,
998 						    struct sctp_paramhdr *);
999 						ph->param_type =
1000 						    htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
1001 						ph->param_length =
1002 						    htons(oper->m_len);
1003 						ippp = (uint32_t *) (ph + 1);
1004 						*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_5);
1005 						ippp++;
1006 						*ippp = chk->rec.data.TSN_seq;
1007 						ippp++;
1008 						*ippp = ((chk->rec.data.stream_number << 16) | chk->rec.data.stream_seq);
1009 
1010 					}
1011 					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_5;
1012 					sctp_abort_an_association(stcb->sctp_ep,
1013 					    stcb, SCTP_PEER_FAULTY, oper);
1014 					*abort_flag = 1;
1015 				}
1016 			}
1017 		}
1018 		return;
1019 	}
1020 	/* Find its place */
1021 	TAILQ_FOREACH(at, &asoc->reasmqueue, sctp_next) {
1022 		if (compare_with_wrap(at->rec.data.TSN_seq,
1023 		    chk->rec.data.TSN_seq, MAX_TSN)) {
1024 			/*
1025 			 * one in queue is bigger than the new one, insert
1026 			 * before this one
1027 			 */
1028 			/* A check */
1029 			asoc->size_on_reasm_queue += chk->send_size;
1030 			sctp_ucount_incr(asoc->cnt_on_reasm_queue);
1031 			next = at;
1032 			TAILQ_INSERT_BEFORE(at, chk, sctp_next);
1033 			break;
1034 		} else if (at->rec.data.TSN_seq == chk->rec.data.TSN_seq) {
1035 			/* Gak, He sent me a duplicate str seq number */
1036 			/*
1037 			 * foo bar, I guess I will just free this new guy,
1038 			 * should we abort too? FIX ME MAYBE? Or it COULD be
1039 			 * that the SSN's have wrapped. Maybe I should
1040 			 * compare to TSN somehow... sigh for now just blow
1041 			 * away the chunk!
1042 			 */
1043 			if (chk->data) {
1044 				sctp_m_freem(chk->data);
1045 				chk->data = NULL;
1046 			}
1047 			sctp_free_remote_addr(chk->whoTo);
1048 			sctp_free_a_chunk(stcb, chk);
1049 			return;
1050 		} else {
1051 			last_flags = at->rec.data.rcv_flags;
1052 			last_tsn = at->rec.data.TSN_seq;
1053 			prev = at;
1054 			if (TAILQ_NEXT(at, sctp_next) == NULL) {
1055 				/*
1056 				 * We are at the end, insert it after this
1057 				 * one
1058 				 */
1059 				/* check it first */
1060 				asoc->size_on_reasm_queue += chk->send_size;
1061 				sctp_ucount_incr(asoc->cnt_on_reasm_queue);
1062 				TAILQ_INSERT_AFTER(&asoc->reasmqueue, at, chk, sctp_next);
1063 				break;
1064 			}
1065 		}
1066 	}
1067 	/* Now the audits */
1068 	if (prev) {
1069 		prev_tsn = chk->rec.data.TSN_seq - 1;
1070 		if (prev_tsn == prev->rec.data.TSN_seq) {
1071 			/*
1072 			 * Ok the one I am dropping onto the end is the
1073 			 * NEXT. A bit of valdiation here.
1074 			 */
1075 			if ((prev->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) ==
1076 			    SCTP_DATA_FIRST_FRAG ||
1077 			    (prev->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) ==
1078 			    SCTP_DATA_MIDDLE_FRAG) {
1079 				/*
1080 				 * Insert chk MUST be a MIDDLE or LAST
1081 				 * fragment
1082 				 */
1083 				if ((chk->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) ==
1084 				    SCTP_DATA_FIRST_FRAG) {
1085 #ifdef SCTP_DEBUG
1086 					if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
1087 						printf("Prev check - It can be a midlle or last but not a first\n");
1088 						printf("Gak, Evil plot, it's a FIRST!\n");
1089 					}
1090 #endif
1091 					oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
1092 					    0, M_DONTWAIT, 1, MT_DATA);
1093 					if (oper) {
1094 						struct sctp_paramhdr *ph;
1095 						uint32_t *ippp;
1096 
1097 						oper->m_len =
1098 						    sizeof(struct sctp_paramhdr) +
1099 						    (3 * sizeof(uint32_t));
1100 						ph = mtod(oper,
1101 						    struct sctp_paramhdr *);
1102 						ph->param_type =
1103 						    htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
1104 						ph->param_length =
1105 						    htons(oper->m_len);
1106 						ippp = (uint32_t *) (ph + 1);
1107 						*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_6);
1108 						ippp++;
1109 						*ippp = chk->rec.data.TSN_seq;
1110 						ippp++;
1111 						*ippp = ((chk->rec.data.stream_number << 16) | chk->rec.data.stream_seq);
1112 
1113 					}
1114 					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_6;
1115 					sctp_abort_an_association(stcb->sctp_ep,
1116 					    stcb, SCTP_PEER_FAULTY, oper);
1117 					*abort_flag = 1;
1118 					return;
1119 				}
1120 				if (chk->rec.data.stream_number !=
1121 				    prev->rec.data.stream_number) {
1122 					/*
1123 					 * Huh, need the correct STR here,
1124 					 * they must be the same.
1125 					 */
1126 #ifdef SCTP_DEBUG
1127 					if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
1128 						printf("Prev check - Gak, Evil plot, ssn:%d not the same as at:%d\n",
1129 						    chk->rec.data.stream_number,
1130 						    prev->rec.data.stream_number);
1131 					}
1132 #endif
1133 					oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
1134 					    0, M_DONTWAIT, 1, MT_DATA);
1135 					if (oper) {
1136 						struct sctp_paramhdr *ph;
1137 						uint32_t *ippp;
1138 
1139 						oper->m_len =
1140 						    sizeof(struct sctp_paramhdr) +
1141 						    (3 * sizeof(uint32_t));
1142 						ph = mtod(oper,
1143 						    struct sctp_paramhdr *);
1144 						ph->param_type =
1145 						    htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
1146 						ph->param_length =
1147 						    htons(oper->m_len);
1148 						ippp = (uint32_t *) (ph + 1);
1149 						*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_7);
1150 						ippp++;
1151 						*ippp = chk->rec.data.TSN_seq;
1152 						ippp++;
1153 						*ippp = ((chk->rec.data.stream_number << 16) | chk->rec.data.stream_seq);
1154 					}
1155 					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_7;
1156 					sctp_abort_an_association(stcb->sctp_ep,
1157 					    stcb, SCTP_PEER_FAULTY, oper);
1158 
1159 					*abort_flag = 1;
1160 					return;
1161 				}
1162 				if ((prev->rec.data.rcv_flags & SCTP_DATA_UNORDERED) == 0 &&
1163 				    chk->rec.data.stream_seq !=
1164 				    prev->rec.data.stream_seq) {
1165 					/*
1166 					 * Huh, need the correct STR here,
1167 					 * they must be the same.
1168 					 */
1169 #ifdef SCTP_DEBUG
1170 					if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
1171 						printf("Prev check - Gak, Evil plot, sseq:%d not the same as at:%d\n",
1172 						    chk->rec.data.stream_seq,
1173 						    prev->rec.data.stream_seq);
1174 					}
1175 #endif
1176 					oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
1177 					    0, M_DONTWAIT, 1, MT_DATA);
1178 					if (oper) {
1179 						struct sctp_paramhdr *ph;
1180 						uint32_t *ippp;
1181 
1182 						oper->m_len =
1183 						    sizeof(struct sctp_paramhdr) +
1184 						    (3 * sizeof(uint32_t));
1185 						ph = mtod(oper,
1186 						    struct sctp_paramhdr *);
1187 						ph->param_type =
1188 						    htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
1189 						ph->param_length =
1190 						    htons(oper->m_len);
1191 						ippp = (uint32_t *) (ph + 1);
1192 						*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_8);
1193 						ippp++;
1194 						*ippp = chk->rec.data.TSN_seq;
1195 						ippp++;
1196 						*ippp = ((chk->rec.data.stream_number << 16) | chk->rec.data.stream_seq);
1197 					}
1198 					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_8;
1199 					sctp_abort_an_association(stcb->sctp_ep,
1200 					    stcb, SCTP_PEER_FAULTY, oper);
1201 
1202 					*abort_flag = 1;
1203 					return;
1204 				}
1205 			} else if ((prev->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) ==
1206 			    SCTP_DATA_LAST_FRAG) {
1207 				/* Insert chk MUST be a FIRST */
1208 				if ((chk->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) !=
1209 				    SCTP_DATA_FIRST_FRAG) {
1210 #ifdef SCTP_DEBUG
1211 					if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
1212 						printf("Prev check - Gak, evil plot, its not FIRST and it must be!\n");
1213 					}
1214 #endif
1215 					oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
1216 					    0, M_DONTWAIT, 1, MT_DATA);
1217 					if (oper) {
1218 						struct sctp_paramhdr *ph;
1219 						uint32_t *ippp;
1220 
1221 						oper->m_len =
1222 						    sizeof(struct sctp_paramhdr) +
1223 						    (3 * sizeof(uint32_t));
1224 						ph = mtod(oper,
1225 						    struct sctp_paramhdr *);
1226 						ph->param_type =
1227 						    htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
1228 						ph->param_length =
1229 						    htons(oper->m_len);
1230 						ippp = (uint32_t *) (ph + 1);
1231 						*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_9);
1232 						ippp++;
1233 						*ippp = chk->rec.data.TSN_seq;
1234 						ippp++;
1235 						*ippp = ((chk->rec.data.stream_number << 16) | chk->rec.data.stream_seq);
1236 
1237 					}
1238 					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_9;
1239 					sctp_abort_an_association(stcb->sctp_ep,
1240 					    stcb, SCTP_PEER_FAULTY, oper);
1241 
1242 					*abort_flag = 1;
1243 					return;
1244 				}
1245 			}
1246 		}
1247 	}
1248 	if (next) {
1249 		post_tsn = chk->rec.data.TSN_seq + 1;
1250 		if (post_tsn == next->rec.data.TSN_seq) {
1251 			/*
1252 			 * Ok the one I am inserting ahead of is my NEXT
1253 			 * one. A bit of valdiation here.
1254 			 */
1255 			if (next->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) {
1256 				/* Insert chk MUST be a last fragment */
1257 				if ((chk->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK)
1258 				    != SCTP_DATA_LAST_FRAG) {
1259 #ifdef SCTP_DEBUG
1260 					if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
1261 						printf("Next chk - Next is FIRST, we must be LAST\n");
1262 						printf("Gak, Evil plot, its not a last!\n");
1263 					}
1264 #endif
1265 					oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
1266 					    0, M_DONTWAIT, 1, MT_DATA);
1267 					if (oper) {
1268 						struct sctp_paramhdr *ph;
1269 						uint32_t *ippp;
1270 
1271 						oper->m_len =
1272 						    sizeof(struct sctp_paramhdr) +
1273 						    (3 * sizeof(uint32_t));
1274 						ph = mtod(oper,
1275 						    struct sctp_paramhdr *);
1276 						ph->param_type =
1277 						    htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
1278 						ph->param_length =
1279 						    htons(oper->m_len);
1280 						ippp = (uint32_t *) (ph + 1);
1281 						*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_10);
1282 						ippp++;
1283 						*ippp = chk->rec.data.TSN_seq;
1284 						ippp++;
1285 						*ippp = ((chk->rec.data.stream_number << 16) | chk->rec.data.stream_seq);
1286 					}
1287 					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_10;
1288 					sctp_abort_an_association(stcb->sctp_ep,
1289 					    stcb, SCTP_PEER_FAULTY, oper);
1290 
1291 					*abort_flag = 1;
1292 					return;
1293 				}
1294 			} else if ((next->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) ==
1295 				    SCTP_DATA_MIDDLE_FRAG ||
1296 				    (next->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) ==
1297 			    SCTP_DATA_LAST_FRAG) {
1298 				/*
1299 				 * Insert chk CAN be MIDDLE or FIRST NOT
1300 				 * LAST
1301 				 */
1302 				if ((chk->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) ==
1303 				    SCTP_DATA_LAST_FRAG) {
1304 #ifdef SCTP_DEBUG
1305 					if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
1306 						printf("Next chk - Next is a MIDDLE/LAST\n");
1307 						printf("Gak, Evil plot, new prev chunk is a LAST\n");
1308 					}
1309 #endif
1310 					oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
1311 					    0, M_DONTWAIT, 1, MT_DATA);
1312 					if (oper) {
1313 						struct sctp_paramhdr *ph;
1314 						uint32_t *ippp;
1315 
1316 						oper->m_len =
1317 						    sizeof(struct sctp_paramhdr) +
1318 						    (3 * sizeof(uint32_t));
1319 						ph = mtod(oper,
1320 						    struct sctp_paramhdr *);
1321 						ph->param_type =
1322 						    htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
1323 						ph->param_length =
1324 						    htons(oper->m_len);
1325 						ippp = (uint32_t *) (ph + 1);
1326 						*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_11);
1327 						ippp++;
1328 						*ippp = chk->rec.data.TSN_seq;
1329 						ippp++;
1330 						*ippp = ((chk->rec.data.stream_number << 16) | chk->rec.data.stream_seq);
1331 
1332 					}
1333 					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_11;
1334 					sctp_abort_an_association(stcb->sctp_ep,
1335 					    stcb, SCTP_PEER_FAULTY, oper);
1336 
1337 					*abort_flag = 1;
1338 					return;
1339 				}
1340 				if (chk->rec.data.stream_number !=
1341 				    next->rec.data.stream_number) {
1342 					/*
1343 					 * Huh, need the correct STR here,
1344 					 * they must be the same.
1345 					 */
1346 #ifdef SCTP_DEBUG
1347 					if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
1348 						printf("Next chk - Gak, Evil plot, ssn:%d not the same as at:%d\n",
1349 						    chk->rec.data.stream_number,
1350 						    next->rec.data.stream_number);
1351 					}
1352 #endif
1353 					oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
1354 					    0, M_DONTWAIT, 1, MT_DATA);
1355 					if (oper) {
1356 						struct sctp_paramhdr *ph;
1357 						uint32_t *ippp;
1358 
1359 						oper->m_len =
1360 						    sizeof(struct sctp_paramhdr) +
1361 						    (3 * sizeof(uint32_t));
1362 						ph = mtod(oper,
1363 						    struct sctp_paramhdr *);
1364 						ph->param_type =
1365 						    htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
1366 						ph->param_length =
1367 						    htons(oper->m_len);
1368 						ippp = (uint32_t *) (ph + 1);
1369 						*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_12);
1370 						ippp++;
1371 						*ippp = chk->rec.data.TSN_seq;
1372 						ippp++;
1373 						*ippp = ((chk->rec.data.stream_number << 16) | chk->rec.data.stream_seq);
1374 
1375 					}
1376 					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_12;
1377 					sctp_abort_an_association(stcb->sctp_ep,
1378 					    stcb, SCTP_PEER_FAULTY, oper);
1379 
1380 					*abort_flag = 1;
1381 					return;
1382 				}
1383 				if ((next->rec.data.rcv_flags & SCTP_DATA_UNORDERED) == 0 &&
1384 				    chk->rec.data.stream_seq !=
1385 				    next->rec.data.stream_seq) {
1386 					/*
1387 					 * Huh, need the correct STR here,
1388 					 * they must be the same.
1389 					 */
1390 #ifdef SCTP_DEBUG
1391 					if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
1392 						printf("Next chk - Gak, Evil plot, sseq:%d not the same as at:%d\n",
1393 						    chk->rec.data.stream_seq,
1394 						    next->rec.data.stream_seq);
1395 					}
1396 #endif
1397 					oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
1398 					    0, M_DONTWAIT, 1, MT_DATA);
1399 					if (oper) {
1400 						struct sctp_paramhdr *ph;
1401 						uint32_t *ippp;
1402 
1403 						oper->m_len =
1404 						    sizeof(struct sctp_paramhdr) +
1405 						    (3 * sizeof(uint32_t));
1406 						ph = mtod(oper,
1407 						    struct sctp_paramhdr *);
1408 						ph->param_type =
1409 						    htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
1410 						ph->param_length =
1411 						    htons(oper->m_len);
1412 						ippp = (uint32_t *) (ph + 1);
1413 						*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_13);
1414 						ippp++;
1415 						*ippp = chk->rec.data.TSN_seq;
1416 						ippp++;
1417 						*ippp = ((chk->rec.data.stream_number << 16) | chk->rec.data.stream_seq);
1418 					}
1419 					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_13;
1420 					sctp_abort_an_association(stcb->sctp_ep,
1421 					    stcb, SCTP_PEER_FAULTY, oper);
1422 
1423 					*abort_flag = 1;
1424 					return;
1425 
1426 				}
1427 			}
1428 		}
1429 	}
1430 	/* Do we need to do some delivery? check */
1431 	sctp_deliver_reasm_check(stcb, asoc);
1432 }
1433 
1434 /*
1435  * This is an unfortunate routine. It checks to make sure a evil guy is not
1436  * stuffing us full of bad packet fragments. A broken peer could also do this
1437  * but this is doubtful. It is to bad I must worry about evil crackers sigh
1438  * :< more cycles.
1439  */
1440 static int
1441 sctp_does_tsn_belong_to_reasm(struct sctp_association *asoc,
1442     uint32_t TSN_seq)
1443 {
1444 	struct sctp_tmit_chunk *at;
1445 	uint32_t tsn_est;
1446 
1447 	TAILQ_FOREACH(at, &asoc->reasmqueue, sctp_next) {
1448 		if (compare_with_wrap(TSN_seq,
1449 		    at->rec.data.TSN_seq, MAX_TSN)) {
1450 			/* is it one bigger? */
1451 			tsn_est = at->rec.data.TSN_seq + 1;
1452 			if (tsn_est == TSN_seq) {
1453 				/* yep. It better be a last then */
1454 				if ((at->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) !=
1455 				    SCTP_DATA_LAST_FRAG) {
1456 					/*
1457 					 * Ok this guy belongs next to a guy
1458 					 * that is NOT last, it should be a
1459 					 * middle/last, not a complete
1460 					 * chunk.
1461 					 */
1462 					return (1);
1463 				} else {
1464 					/*
1465 					 * This guy is ok since its a LAST
1466 					 * and the new chunk is a fully
1467 					 * self- contained one.
1468 					 */
1469 					return (0);
1470 				}
1471 			}
1472 		} else if (TSN_seq == at->rec.data.TSN_seq) {
1473 			/* Software error since I have a dup? */
1474 			return (1);
1475 		} else {
1476 			/*
1477 			 * Ok, 'at' is larger than new chunk but does it
1478 			 * need to be right before it.
1479 			 */
1480 			tsn_est = TSN_seq + 1;
1481 			if (tsn_est == at->rec.data.TSN_seq) {
1482 				/* Yep, It better be a first */
1483 				if ((at->rec.data.rcv_flags & SCTP_DATA_FRAG_MASK) !=
1484 				    SCTP_DATA_FIRST_FRAG) {
1485 					return (1);
1486 				} else {
1487 					return (0);
1488 				}
1489 			}
1490 		}
1491 	}
1492 	return (0);
1493 }
1494 
1495 
1496 extern unsigned int sctp_max_chunks_on_queue;
1497 static int
1498 sctp_process_a_data_chunk(struct sctp_tcb *stcb, struct sctp_association *asoc,
1499     struct mbuf **m, int offset, struct sctp_data_chunk *ch, int chk_length,
1500     struct sctp_nets *net, uint32_t * high_tsn, int *abort_flag,
1501     int *break_flag, int last_chunk)
1502 {
1503 	/* Process a data chunk */
1504 	/* struct sctp_tmit_chunk *chk; */
1505 	struct sctp_tmit_chunk *chk;
1506 	uint32_t tsn, gap;
1507 	struct mbuf *dmbuf;
1508 	int indx, the_len;
1509 	uint16_t strmno, strmseq;
1510 	struct mbuf *oper;
1511 	struct sctp_queued_to_read *control;
1512 
1513 	chk = NULL;
1514 	tsn = ntohl(ch->dp.tsn);
1515 #ifdef SCTP_MAP_LOGGING
1516 	sctp_log_map(0, tsn, asoc->cumulative_tsn, SCTP_MAP_PREPARE_SLIDE);
1517 #endif
1518 	if (compare_with_wrap(asoc->cumulative_tsn, tsn, MAX_TSN) ||
1519 	    asoc->cumulative_tsn == tsn) {
1520 		/* It is a duplicate */
1521 		SCTP_STAT_INCR(sctps_recvdupdata);
1522 		if (asoc->numduptsns < SCTP_MAX_DUP_TSNS) {
1523 			/* Record a dup for the next outbound sack */
1524 			asoc->dup_tsns[asoc->numduptsns] = tsn;
1525 			asoc->numduptsns++;
1526 		}
1527 		return (0);
1528 	}
1529 	/* Calculate the number of TSN's between the base and this TSN */
1530 	if (tsn >= asoc->mapping_array_base_tsn) {
1531 		gap = tsn - asoc->mapping_array_base_tsn;
1532 	} else {
1533 		gap = (MAX_TSN - asoc->mapping_array_base_tsn) + tsn + 1;
1534 	}
1535 	if (gap >= (SCTP_MAPPING_ARRAY << 3)) {
1536 		/* Can't hold the bit in the mapping at max array, toss it */
1537 		return (0);
1538 	}
1539 	if (gap >= (uint32_t) (asoc->mapping_array_size << 3)) {
1540 		if (sctp_expand_mapping_array(asoc)) {
1541 			/* Can't expand, drop it */
1542 			return (0);
1543 		}
1544 	}
1545 	if (compare_with_wrap(tsn, *high_tsn, MAX_TSN)) {
1546 		*high_tsn = tsn;
1547 	}
1548 	/* See if we have received this one already */
1549 	if (SCTP_IS_TSN_PRESENT(asoc->mapping_array, gap)) {
1550 		SCTP_STAT_INCR(sctps_recvdupdata);
1551 		if (asoc->numduptsns < SCTP_MAX_DUP_TSNS) {
1552 			/* Record a dup for the next outbound sack */
1553 			asoc->dup_tsns[asoc->numduptsns] = tsn;
1554 			asoc->numduptsns++;
1555 		}
1556 		if (!callout_pending(&asoc->dack_timer.timer)) {
1557 			/*
1558 			 * By starting the timer we assure that we WILL sack
1559 			 * at the end of the packet when sctp_sack_check
1560 			 * gets called.
1561 			 */
1562 			sctp_timer_start(SCTP_TIMER_TYPE_RECV, stcb->sctp_ep,
1563 			    stcb, NULL);
1564 		}
1565 		return (0);
1566 	}
1567 	/*
1568 	 * Check to see about the GONE flag, duplicates would cause a sack
1569 	 * to be sent up above
1570 	 */
1571 	if (stcb && ((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) ||
1572 	    (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_ALLGONE) ||
1573 	    (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET))
1574 	    ) {
1575 		/*
1576 		 * wait a minute, this guy is gone, there is no longer a
1577 		 * receiver. Send peer an ABORT!
1578 		 */
1579 		struct mbuf *op_err;
1580 
1581 		op_err = sctp_generate_invmanparam(SCTP_CAUSE_OUT_OF_RESC);
1582 		sctp_abort_an_association(stcb->sctp_ep, stcb, 0, op_err);
1583 		*abort_flag = 1;
1584 		return (0);
1585 	}
1586 	/*
1587 	 * Now before going further we see if there is room. If NOT then we
1588 	 * MAY let one through only IF this TSN is the one we are waiting
1589 	 * for on a partial delivery API.
1590 	 */
1591 
1592 	/* now do the tests */
1593 	if (((asoc->cnt_on_all_streams +
1594 	    asoc->cnt_on_reasm_queue +
1595 	    asoc->cnt_msg_on_sb) > sctp_max_chunks_on_queue) ||
1596 	    (((int)asoc->my_rwnd) <= 0)) {
1597 		/*
1598 		 * When we have NO room in the rwnd we check to make sure
1599 		 * the reader is doing its job...
1600 		 */
1601 		if (stcb->sctp_socket->so_rcv.sb_cc) {
1602 			/* some to read, wake-up */
1603 			sctp_sorwakeup(stcb->sctp_ep, stcb->sctp_socket);
1604 		}
1605 		/* now is it in the mapping array of what we have accepted? */
1606 		if (compare_with_wrap(tsn,
1607 		    asoc->highest_tsn_inside_map, MAX_TSN)) {
1608 
1609 			/* Nope not in the valid range dump it */
1610 #ifdef SCTP_DEBUG
1611 			if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
1612 				printf("My rwnd overrun1:tsn:%lx rwnd %lu sbspace:%ld\n",
1613 				    (u_long)tsn, (u_long)asoc->my_rwnd,
1614 				    sctp_sbspace(&stcb->asoc, &stcb->sctp_socket->so_rcv));
1615 
1616 			}
1617 #endif
1618 			sctp_set_rwnd(stcb, asoc);
1619 			if ((asoc->cnt_on_all_streams +
1620 			    asoc->cnt_on_reasm_queue +
1621 			    asoc->cnt_msg_on_sb) > sctp_max_chunks_on_queue) {
1622 				SCTP_STAT_INCR(sctps_datadropchklmt);
1623 			} else {
1624 				SCTP_STAT_INCR(sctps_datadroprwnd);
1625 			}
1626 			indx = *break_flag;
1627 			*break_flag = 1;
1628 			return (0);
1629 		}
1630 	}
1631 	strmno = ntohs(ch->dp.stream_id);
1632 	if (strmno >= asoc->streamincnt) {
1633 		struct sctp_paramhdr *phdr;
1634 		struct mbuf *mb;
1635 
1636 		mb = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) * 2),
1637 		    1, M_DONTWAIT, 1, MT_DATA);
1638 		if (mb != NULL) {
1639 			/* add some space up front so prepend will work well */
1640 			mb->m_data += sizeof(struct sctp_chunkhdr);
1641 			phdr = mtod(mb, struct sctp_paramhdr *);
1642 			/*
1643 			 * Error causes are just param's and this one has
1644 			 * two back to back phdr, one with the error type
1645 			 * and size, the other with the streamid and a rsvd
1646 			 */
1647 			mb->m_pkthdr.len = mb->m_len =
1648 			    (sizeof(struct sctp_paramhdr) * 2);
1649 			phdr->param_type = htons(SCTP_CAUSE_INVALID_STREAM);
1650 			phdr->param_length =
1651 			    htons(sizeof(struct sctp_paramhdr) * 2);
1652 			phdr++;
1653 			/* We insert the stream in the type field */
1654 			phdr->param_type = ch->dp.stream_id;
1655 			/* And set the length to 0 for the rsvd field */
1656 			phdr->param_length = 0;
1657 			sctp_queue_op_err(stcb, mb);
1658 		}
1659 		SCTP_STAT_INCR(sctps_badsid);
1660 		return (0);
1661 	}
1662 	/*
1663 	 * Before we continue lets validate that we are not being fooled by
1664 	 * an evil attacker. We can only have 4k chunks based on our TSN
1665 	 * spread allowed by the mapping array 512 * 8 bits, so there is no
1666 	 * way our stream sequence numbers could have wrapped. We of course
1667 	 * only validate the FIRST fragment so the bit must be set.
1668 	 */
1669 	strmseq = ntohs(ch->dp.stream_sequence);
1670 	if ((ch->ch.chunk_flags & SCTP_DATA_FIRST_FRAG) &&
1671 	    (ch->ch.chunk_flags & SCTP_DATA_UNORDERED) == 0 &&
1672 	    (compare_with_wrap(asoc->strmin[strmno].last_sequence_delivered,
1673 	    strmseq, MAX_SEQ) ||
1674 	    asoc->strmin[strmno].last_sequence_delivered == strmseq)) {
1675 		/* The incoming sseq is behind where we last delivered? */
1676 #ifdef SCTP_DEBUG
1677 		if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
1678 			printf("EVIL/Broken-Dup S-SEQ:%d delivered:%d from peer, Abort!\n",
1679 			    strmseq,
1680 			    asoc->strmin[strmno].last_sequence_delivered);
1681 		}
1682 #endif
1683 		/*
1684 		 * throw it in the stream so it gets cleaned up in
1685 		 * association destruction
1686 		 */
1687 		oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
1688 		    0, M_DONTWAIT, 1, MT_DATA);
1689 		if (oper) {
1690 			struct sctp_paramhdr *ph;
1691 			uint32_t *ippp;
1692 
1693 			oper->m_len = sizeof(struct sctp_paramhdr) +
1694 			    (3 * sizeof(uint32_t));
1695 			ph = mtod(oper, struct sctp_paramhdr *);
1696 			ph->param_type = htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
1697 			ph->param_length = htons(oper->m_len);
1698 			ippp = (uint32_t *) (ph + 1);
1699 			*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_14);
1700 			ippp++;
1701 			*ippp = tsn;
1702 			ippp++;
1703 			*ippp = ((strmno << 16) | strmseq);
1704 
1705 		}
1706 		stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_14;
1707 		sctp_abort_an_association(stcb->sctp_ep, stcb,
1708 		    SCTP_PEER_FAULTY, oper);
1709 		*abort_flag = 1;
1710 		return (0);
1711 	}
1712 	the_len = (chk_length - sizeof(struct sctp_data_chunk));
1713 	if (last_chunk == 0) {
1714 		dmbuf = sctp_m_copym(*m,
1715 		    (offset + sizeof(struct sctp_data_chunk)),
1716 		    the_len, M_DONTWAIT);
1717 #ifdef SCTP_MBUF_LOGGING
1718 		{
1719 			struct mbuf *mat;
1720 
1721 			mat = dmbuf;
1722 			while (mat) {
1723 				if (mat->m_flags & M_EXT) {
1724 					sctp_log_mb(mat, SCTP_MBUF_ICOPY);
1725 				}
1726 				mat = mat->m_next;
1727 			}
1728 		}
1729 #endif
1730 	} else {
1731 		/* We can steal the last chunk */
1732 		dmbuf = *m;
1733 		/* lop off the top part */
1734 		m_adj(dmbuf, (offset + sizeof(struct sctp_data_chunk)));
1735 		if (dmbuf->m_pkthdr.len > the_len) {
1736 			/* Trim the end round bytes off  too */
1737 			m_adj(dmbuf, -(dmbuf->m_pkthdr.len - the_len));
1738 		}
1739 	}
1740 	if (dmbuf == NULL) {
1741 		SCTP_STAT_INCR(sctps_nomem);
1742 		return (0);
1743 	}
1744 	if ((ch->ch.chunk_flags & SCTP_DATA_NOT_FRAG) == SCTP_DATA_NOT_FRAG &&
1745 	    asoc->fragmented_delivery_inprogress == 0 &&
1746 	    TAILQ_EMPTY(&asoc->resetHead) &&
1747 	    ((ch->ch.chunk_flags & SCTP_DATA_UNORDERED) ||
1748 	    ((asoc->strmin[strmno].last_sequence_delivered + 1) == strmseq &&
1749 	    TAILQ_EMPTY(&asoc->strmin[strmno].inqueue)))) {
1750 		/* Candidate for express delivery */
1751 		/*
1752 		 * Its not fragmented, No PD-API is up, Nothing in the
1753 		 * delivery queue, Its un-ordered OR ordered and the next to
1754 		 * deliver AND nothing else is stuck on the stream queue,
1755 		 * And there is room for it in the socket buffer. Lets just
1756 		 * stuff it up the buffer....
1757 		 */
1758 
1759 		/* It would be nice to avoid this copy if we could :< */
1760 		sctp_alloc_a_readq(stcb, control);
1761 		sctp_build_readq_entry_mac(control, stcb, asoc->context, net, tsn,
1762 		    ch->dp.protocol_id,
1763 		    stcb->asoc.context,
1764 		    strmno, strmseq,
1765 		    ch->ch.chunk_flags,
1766 		    dmbuf);
1767 		if (control == NULL) {
1768 			goto failed_express_del;
1769 		}
1770 		sctp_add_to_readq(stcb->sctp_ep, stcb, control, &stcb->sctp_socket->so_rcv, 1);
1771 		if ((ch->ch.chunk_flags & SCTP_DATA_UNORDERED) == 0) {
1772 			/* for ordered, bump what we delivered */
1773 			asoc->strmin[strmno].last_sequence_delivered++;
1774 		}
1775 		SCTP_STAT_INCR(sctps_recvexpress);
1776 #ifdef SCTP_STR_LOGGING
1777 		sctp_log_strm_del_alt(stcb, tsn, strmseq, strmno,
1778 		    SCTP_STR_LOG_FROM_EXPRS_DEL);
1779 #endif
1780 		control = NULL;
1781 		goto finish_express_del;
1782 	}
1783 failed_express_del:
1784 	/* If we reach here this is a new chunk */
1785 	chk = NULL;
1786 	control = NULL;
1787 	/* Express for fragmented delivery? */
1788 	if ((asoc->fragmented_delivery_inprogress) &&
1789 	    (stcb->asoc.control_pdapi) &&
1790 	    (asoc->str_of_pdapi == strmno) &&
1791 	    (asoc->ssn_of_pdapi == strmseq)
1792 	    ) {
1793 		control = stcb->asoc.control_pdapi;
1794 		if ((ch->ch.chunk_flags & SCTP_DATA_FIRST_FRAG) == SCTP_DATA_FIRST_FRAG) {
1795 			/* Can't be another first? */
1796 			goto failed_pdapi_express_del;
1797 		}
1798 		if (tsn == (control->sinfo_tsn + 1)) {
1799 			/* Yep, we can add it on */
1800 			int end = 0;
1801 			uint32_t cumack;
1802 
1803 			if (ch->ch.chunk_flags & SCTP_DATA_LAST_FRAG) {
1804 				end = 1;
1805 			}
1806 			cumack = asoc->cumulative_tsn;
1807 			if ((cumack + 1) == tsn)
1808 				cumack = tsn;
1809 
1810 			if (sctp_append_to_readq(stcb->sctp_ep, stcb, control, dmbuf, end,
1811 			    tsn,
1812 			    &stcb->sctp_socket->so_rcv)) {
1813 				printf("Append fails end:%d\n", end);
1814 				goto failed_pdapi_express_del;
1815 			}
1816 			SCTP_STAT_INCR(sctps_recvexpressm);
1817 			control->sinfo_tsn = tsn;
1818 			asoc->tsn_last_delivered = tsn;
1819 			asoc->fragment_flags = ch->ch.chunk_flags;
1820 			asoc->tsn_of_pdapi_last_delivered = tsn;
1821 			asoc->last_flags_delivered = ch->ch.chunk_flags;
1822 			asoc->last_strm_seq_delivered = strmseq;
1823 			asoc->last_strm_no_delivered = strmno;
1824 
1825 			if (end) {
1826 				/* clean up the flags and such */
1827 				asoc->fragmented_delivery_inprogress = 0;
1828 				if ((ch->ch.chunk_flags & SCTP_DATA_UNORDERED) == 0) {
1829 					asoc->strmin[strmno].last_sequence_delivered++;
1830 				}
1831 				stcb->asoc.control_pdapi = NULL;
1832 			}
1833 			control = NULL;
1834 			goto finish_express_del;
1835 		}
1836 	}
1837 failed_pdapi_express_del:
1838 	control = NULL;
1839 	if ((ch->ch.chunk_flags & SCTP_DATA_NOT_FRAG) != SCTP_DATA_NOT_FRAG) {
1840 		sctp_alloc_a_chunk(stcb, chk);
1841 		if (chk == NULL) {
1842 			/* No memory so we drop the chunk */
1843 			SCTP_STAT_INCR(sctps_nomem);
1844 			if (last_chunk == 0) {
1845 				/* we copied it, free the copy */
1846 				sctp_m_freem(dmbuf);
1847 			}
1848 			return (0);
1849 		}
1850 		chk->rec.data.TSN_seq = tsn;
1851 		chk->no_fr_allowed = 0;
1852 		chk->rec.data.stream_seq = strmseq;
1853 		chk->rec.data.stream_number = strmno;
1854 		chk->rec.data.payloadtype = ch->dp.protocol_id;
1855 		chk->rec.data.context = stcb->asoc.context;
1856 		chk->rec.data.doing_fast_retransmit = 0;
1857 		chk->rec.data.rcv_flags = ch->ch.chunk_flags;
1858 		chk->asoc = asoc;
1859 		chk->send_size = the_len;
1860 		chk->whoTo = net;
1861 		atomic_add_int(&net->ref_count, 1);
1862 		chk->data = dmbuf;
1863 	} else {
1864 		sctp_alloc_a_readq(stcb, control);
1865 		sctp_build_readq_entry_mac(control, stcb, asoc->context, net, tsn,
1866 		    ch->dp.protocol_id,
1867 		    stcb->asoc.context,
1868 		    strmno, strmseq,
1869 		    ch->ch.chunk_flags,
1870 		    dmbuf);
1871 		if (control == NULL) {
1872 			/* No memory so we drop the chunk */
1873 			SCTP_STAT_INCR(sctps_nomem);
1874 			if (last_chunk == 0) {
1875 				/* we copied it, free the copy */
1876 				sctp_m_freem(dmbuf);
1877 			}
1878 			return (0);
1879 		}
1880 		control->length = the_len;
1881 	}
1882 
1883 	/* Mark it as received */
1884 	/* Now queue it where it belongs */
1885 	if (control != NULL) {
1886 		/* First a sanity check */
1887 		if (asoc->fragmented_delivery_inprogress) {
1888 			/*
1889 			 * Ok, we have a fragmented delivery in progress if
1890 			 * this chunk is next to deliver OR belongs in our
1891 			 * view to the reassembly, the peer is evil or
1892 			 * broken.
1893 			 */
1894 			uint32_t estimate_tsn;
1895 
1896 			estimate_tsn = asoc->tsn_last_delivered + 1;
1897 			if (TAILQ_EMPTY(&asoc->reasmqueue) &&
1898 			    (estimate_tsn == control->sinfo_tsn)) {
1899 				/* Evil/Broke peer */
1900 				sctp_m_freem(control->data);
1901 				control->data = NULL;
1902 				sctp_free_remote_addr(control->whoFrom);
1903 				sctp_free_a_readq(stcb, control);
1904 				oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
1905 				    0, M_DONTWAIT, 1, MT_DATA);
1906 				if (oper) {
1907 					struct sctp_paramhdr *ph;
1908 					uint32_t *ippp;
1909 
1910 					oper->m_len =
1911 					    sizeof(struct sctp_paramhdr) +
1912 					    (3 * sizeof(uint32_t));
1913 					ph = mtod(oper, struct sctp_paramhdr *);
1914 					ph->param_type =
1915 					    htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
1916 					ph->param_length = htons(oper->m_len);
1917 					ippp = (uint32_t *) (ph + 1);
1918 					*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_15);
1919 					ippp++;
1920 					*ippp = tsn;
1921 					ippp++;
1922 					*ippp = ((strmno << 16) | strmseq);
1923 				}
1924 				stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_15;
1925 				sctp_abort_an_association(stcb->sctp_ep, stcb,
1926 				    SCTP_PEER_FAULTY, oper);
1927 
1928 				*abort_flag = 1;
1929 				return (0);
1930 			} else {
1931 				if (sctp_does_tsn_belong_to_reasm(asoc, control->sinfo_tsn)) {
1932 					sctp_m_freem(control->data);
1933 					control->data = NULL;
1934 					sctp_free_remote_addr(control->whoFrom);
1935 					sctp_free_a_readq(stcb, control);
1936 
1937 					oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
1938 					    0, M_DONTWAIT, 1, MT_DATA);
1939 					if (oper) {
1940 						struct sctp_paramhdr *ph;
1941 						uint32_t *ippp;
1942 
1943 						oper->m_len =
1944 						    sizeof(struct sctp_paramhdr) +
1945 						    (3 * sizeof(uint32_t));
1946 						ph = mtod(oper,
1947 						    struct sctp_paramhdr *);
1948 						ph->param_type =
1949 						    htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
1950 						ph->param_length =
1951 						    htons(oper->m_len);
1952 						ippp = (uint32_t *) (ph + 1);
1953 						*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_16);
1954 						ippp++;
1955 						*ippp = tsn;
1956 						ippp++;
1957 						*ippp = ((strmno << 16) | strmseq);
1958 					}
1959 					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_16;
1960 					sctp_abort_an_association(stcb->sctp_ep,
1961 					    stcb, SCTP_PEER_FAULTY, oper);
1962 
1963 					*abort_flag = 1;
1964 					return (0);
1965 				}
1966 			}
1967 		} else {
1968 			/* No PDAPI running */
1969 			if (!TAILQ_EMPTY(&asoc->reasmqueue)) {
1970 				/*
1971 				 * Reassembly queue is NOT empty validate
1972 				 * that this tsn does not need to be in
1973 				 * reasembly queue. If it does then our peer
1974 				 * is broken or evil.
1975 				 */
1976 				if (sctp_does_tsn_belong_to_reasm(asoc, control->sinfo_tsn)) {
1977 					sctp_m_freem(control->data);
1978 					control->data = NULL;
1979 					sctp_free_remote_addr(control->whoFrom);
1980 					sctp_free_a_readq(stcb, control);
1981 					oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
1982 					    0, M_DONTWAIT, 1, MT_DATA);
1983 					if (oper) {
1984 						struct sctp_paramhdr *ph;
1985 						uint32_t *ippp;
1986 
1987 						oper->m_len =
1988 						    sizeof(struct sctp_paramhdr) +
1989 						    (3 * sizeof(uint32_t));
1990 						ph = mtod(oper,
1991 						    struct sctp_paramhdr *);
1992 						ph->param_type =
1993 						    htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
1994 						ph->param_length =
1995 						    htons(oper->m_len);
1996 						ippp = (uint32_t *) (ph + 1);
1997 						*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_17);
1998 						ippp++;
1999 						*ippp = tsn;
2000 						ippp++;
2001 						*ippp = ((strmno << 16) | strmseq);
2002 					}
2003 					stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_17;
2004 					sctp_abort_an_association(stcb->sctp_ep,
2005 					    stcb, SCTP_PEER_FAULTY, oper);
2006 
2007 					*abort_flag = 1;
2008 					return (0);
2009 				}
2010 			}
2011 		}
2012 		/* ok, if we reach here we have passed the sanity checks */
2013 		if (ch->ch.chunk_flags & SCTP_DATA_UNORDERED) {
2014 			/* queue directly into socket buffer */
2015 			sctp_add_to_readq(stcb->sctp_ep, stcb,
2016 			    control,
2017 			    &stcb->sctp_socket->so_rcv, 1);
2018 		} else {
2019 			/*
2020 			 * Special check for when streams are resetting. We
2021 			 * could be more smart about this and check the
2022 			 * actual stream to see if it is not being reset..
2023 			 * that way we would not create a HOLB when amongst
2024 			 * streams being reset and those not being reset.
2025 			 *
2026 			 * We take complete messages that have a stream reset
2027 			 * intervening (aka the TSN is after where our
2028 			 * cum-ack needs to be) off and put them on a
2029 			 * pending_reply_queue. The reassembly ones we do
2030 			 * not have to worry about since they are all sorted
2031 			 * and proceessed by TSN order. It is only the
2032 			 * singletons I must worry about.
2033 			 */
2034 			struct sctp_stream_reset_list *liste;
2035 
2036 			if (((liste = TAILQ_FIRST(&asoc->resetHead)) != NULL) &&
2037 			    ((compare_with_wrap(tsn, liste->tsn, MAX_TSN)) ||
2038 			    (tsn == ntohl(liste->tsn)))
2039 			    ) {
2040 				/*
2041 				 * yep its past where we need to reset... go
2042 				 * ahead and queue it.
2043 				 */
2044 				if (TAILQ_EMPTY(&asoc->pending_reply_queue)) {
2045 					/* first one on */
2046 					TAILQ_INSERT_TAIL(&asoc->pending_reply_queue, control, next);
2047 				} else {
2048 					struct sctp_queued_to_read *ctlOn;
2049 					unsigned char inserted = 0;
2050 
2051 					ctlOn = TAILQ_FIRST(&asoc->pending_reply_queue);
2052 					while (ctlOn) {
2053 						if (compare_with_wrap(control->sinfo_tsn,
2054 						    ctlOn->sinfo_tsn, MAX_TSN)) {
2055 							ctlOn = TAILQ_NEXT(ctlOn, next);
2056 						} else {
2057 							/* found it */
2058 							TAILQ_INSERT_BEFORE(ctlOn, control, next);
2059 							inserted = 1;
2060 							break;
2061 						}
2062 					}
2063 					if (inserted == 0) {
2064 						/*
2065 						 * must be put at end, use
2066 						 * prevP (all setup from
2067 						 * loop) to setup nextP.
2068 						 */
2069 						TAILQ_INSERT_TAIL(&asoc->pending_reply_queue, control, next);
2070 					}
2071 				}
2072 			} else {
2073 				sctp_queue_data_to_stream(stcb, asoc, control, abort_flag);
2074 				if (*abort_flag) {
2075 					return (0);
2076 				}
2077 			}
2078 		}
2079 	} else {
2080 		/* Into the re-assembly queue */
2081 		sctp_queue_data_for_reasm(stcb, asoc, chk, abort_flag);
2082 		if (*abort_flag) {
2083 			/*
2084 			 * the assoc is now gone and chk was put onto the
2085 			 * reasm queue, which has all been freed.
2086 			 */
2087 			*m = NULL;
2088 			return (0);
2089 		}
2090 	}
2091 finish_express_del:
2092 	if (compare_with_wrap(tsn, asoc->highest_tsn_inside_map, MAX_TSN)) {
2093 		/* we have a new high score */
2094 		asoc->highest_tsn_inside_map = tsn;
2095 #ifdef SCTP_MAP_LOGGING
2096 		sctp_log_map(0, 2, asoc->highest_tsn_inside_map, SCTP_MAP_SLIDE_RESULT);
2097 #endif
2098 	}
2099 	if (tsn == (asoc->cumulative_tsn + 1)) {
2100 		/* Update cum-ack */
2101 		asoc->cumulative_tsn = tsn;
2102 	}
2103 	if (last_chunk) {
2104 		*m = NULL;
2105 	}
2106 	if ((ch->ch.chunk_flags & SCTP_DATA_UNORDERED) == 0) {
2107 		SCTP_STAT_INCR_COUNTER64(sctps_inorderchunks);
2108 	} else {
2109 		SCTP_STAT_INCR_COUNTER64(sctps_inunorderchunks);
2110 	}
2111 	SCTP_STAT_INCR(sctps_recvdata);
2112 	/* Set it present please */
2113 #ifdef SCTP_STR_LOGGING
2114 	sctp_log_strm_del_alt(stcb, tsn, strmseq, strmno, SCTP_STR_LOG_FROM_MARK_TSN);
2115 #endif
2116 #ifdef SCTP_MAP_LOGGING
2117 	sctp_log_map(asoc->mapping_array_base_tsn, asoc->cumulative_tsn,
2118 	    asoc->highest_tsn_inside_map, SCTP_MAP_PREPARE_SLIDE);
2119 #endif
2120 	SCTP_SET_TSN_PRESENT(asoc->mapping_array, gap);
2121 	return (1);
2122 }
2123 
2124 int8_t sctp_map_lookup_tab[256] = {
2125 	-1, 0, -1, 1, -1, 0, -1, 2,
2126 	-1, 0, -1, 1, -1, 0, -1, 3,
2127 	-1, 0, -1, 1, -1, 0, -1, 2,
2128 	-1, 0, -1, 1, -1, 0, -1, 4,
2129 	-1, 0, -1, 1, -1, 0, -1, 2,
2130 	-1, 0, -1, 1, -1, 0, -1, 3,
2131 	-1, 0, -1, 1, -1, 0, -1, 2,
2132 	-1, 0, -1, 1, -1, 0, -1, 5,
2133 	-1, 0, -1, 1, -1, 0, -1, 2,
2134 	-1, 0, -1, 1, -1, 0, -1, 3,
2135 	-1, 0, -1, 1, -1, 0, -1, 2,
2136 	-1, 0, -1, 1, -1, 0, -1, 4,
2137 	-1, 0, -1, 1, -1, 0, -1, 2,
2138 	-1, 0, -1, 1, -1, 0, -1, 3,
2139 	-1, 0, -1, 1, -1, 0, -1, 2,
2140 	-1, 0, -1, 1, -1, 0, -1, 6,
2141 	-1, 0, -1, 1, -1, 0, -1, 2,
2142 	-1, 0, -1, 1, -1, 0, -1, 3,
2143 	-1, 0, -1, 1, -1, 0, -1, 2,
2144 	-1, 0, -1, 1, -1, 0, -1, 4,
2145 	-1, 0, -1, 1, -1, 0, -1, 2,
2146 	-1, 0, -1, 1, -1, 0, -1, 3,
2147 	-1, 0, -1, 1, -1, 0, -1, 2,
2148 	-1, 0, -1, 1, -1, 0, -1, 5,
2149 	-1, 0, -1, 1, -1, 0, -1, 2,
2150 	-1, 0, -1, 1, -1, 0, -1, 3,
2151 	-1, 0, -1, 1, -1, 0, -1, 2,
2152 	-1, 0, -1, 1, -1, 0, -1, 4,
2153 	-1, 0, -1, 1, -1, 0, -1, 2,
2154 	-1, 0, -1, 1, -1, 0, -1, 3,
2155 	-1, 0, -1, 1, -1, 0, -1, 2,
2156 	-1, 0, -1, 1, -1, 0, -1, 7,
2157 };
2158 
2159 
2160 void
2161 sctp_sack_check(struct sctp_tcb *stcb, int ok_to_sack, int was_a_gap, int *abort_flag)
2162 {
2163 	/*
2164 	 * Now we also need to check the mapping array in a couple of ways.
2165 	 * 1) Did we move the cum-ack point?
2166 	 */
2167 	struct sctp_association *asoc;
2168 	int i, at;
2169 	int all_ones;
2170 	int slide_from, slide_end, lgap, distance;
2171 
2172 #ifdef SCTP_MAP_LOGGING
2173 	uint32_t old_cumack, old_base, old_highest;
2174 	unsigned char aux_array[64];
2175 
2176 #endif
2177 	struct sctp_stream_reset_list *liste;
2178 
2179 	asoc = &stcb->asoc;
2180 	at = 0;
2181 
2182 #ifdef SCTP_MAP_LOGGING
2183 	old_cumack = asoc->cumulative_tsn;
2184 	old_base = asoc->mapping_array_base_tsn;
2185 	old_highest = asoc->highest_tsn_inside_map;
2186 	if (asoc->mapping_array_size < 64)
2187 		memcpy(aux_array, asoc->mapping_array,
2188 		    asoc->mapping_array_size);
2189 	else
2190 		memcpy(aux_array, asoc->mapping_array, 64);
2191 #endif
2192 
2193 	/*
2194 	 * We could probably improve this a small bit by calculating the
2195 	 * offset of the current cum-ack as the starting point.
2196 	 */
2197 	all_ones = 1;
2198 	at = 0;
2199 	for (i = 0; i < stcb->asoc.mapping_array_size; i++) {
2200 		if (asoc->mapping_array[i] == 0xff) {
2201 			at += 8;
2202 		} else {
2203 			/* there is a 0 bit */
2204 			all_ones = 0;
2205 			at += sctp_map_lookup_tab[asoc->mapping_array[i]];
2206 			break;
2207 		}
2208 	}
2209 	asoc->cumulative_tsn = asoc->mapping_array_base_tsn + at;
2210 	/* at is one off, since in the table a embedded -1 is present */
2211 	at++;
2212 
2213 	if (compare_with_wrap(asoc->cumulative_tsn,
2214 	    asoc->highest_tsn_inside_map,
2215 	    MAX_TSN)) {
2216 #ifdef INVARIANTS
2217 		panic("huh, cumack greater than high-tsn in map");
2218 #else
2219 		printf("huh, cumack greater than high-tsn in map - should panic?\n");
2220 		asoc->highest_tsn_inside_map = asoc->cumulative_tsn;
2221 #endif
2222 	}
2223 	if (all_ones ||
2224 	    (asoc->cumulative_tsn == asoc->highest_tsn_inside_map && at >= 8)) {
2225 		/* The complete array was completed by a single FR */
2226 		/* higest becomes the cum-ack */
2227 		int clr;
2228 
2229 		asoc->cumulative_tsn = asoc->highest_tsn_inside_map;
2230 		/* clear the array */
2231 		if (all_ones)
2232 			clr = asoc->mapping_array_size;
2233 		else {
2234 			clr = (at >> 3) + 1;
2235 			/*
2236 			 * this should be the allones case but just in case
2237 			 * :>
2238 			 */
2239 			if (clr > asoc->mapping_array_size)
2240 				clr = asoc->mapping_array_size;
2241 		}
2242 		memset(asoc->mapping_array, 0, clr);
2243 		/* base becomes one ahead of the cum-ack */
2244 		asoc->mapping_array_base_tsn = asoc->cumulative_tsn + 1;
2245 #ifdef SCTP_MAP_LOGGING
2246 		sctp_log_map(old_base, old_cumack, old_highest,
2247 		    SCTP_MAP_PREPARE_SLIDE);
2248 		sctp_log_map(asoc->mapping_array_base_tsn, asoc->cumulative_tsn,
2249 		    asoc->highest_tsn_inside_map, SCTP_MAP_SLIDE_CLEARED);
2250 #endif
2251 	} else if (at >= 8) {
2252 		/* we can slide the mapping array down */
2253 		/* Calculate the new byte postion we can move down */
2254 		slide_from = at >> 3;
2255 		/*
2256 		 * now calculate the ceiling of the move using our highest
2257 		 * TSN value
2258 		 */
2259 		if (asoc->highest_tsn_inside_map >= asoc->mapping_array_base_tsn) {
2260 			lgap = asoc->highest_tsn_inside_map -
2261 			    asoc->mapping_array_base_tsn;
2262 		} else {
2263 			lgap = (MAX_TSN - asoc->mapping_array_base_tsn) +
2264 			    asoc->highest_tsn_inside_map + 1;
2265 		}
2266 		slide_end = lgap >> 3;
2267 		if (slide_end < slide_from) {
2268 			panic("impossible slide");
2269 		}
2270 		distance = (slide_end - slide_from) + 1;
2271 #ifdef SCTP_MAP_LOGGING
2272 		sctp_log_map(old_base, old_cumack, old_highest,
2273 		    SCTP_MAP_PREPARE_SLIDE);
2274 		sctp_log_map((uint32_t) slide_from, (uint32_t) slide_end,
2275 		    (uint32_t) lgap, SCTP_MAP_SLIDE_FROM);
2276 #endif
2277 		if (distance + slide_from > asoc->mapping_array_size ||
2278 		    distance < 0) {
2279 			/*
2280 			 * Here we do NOT slide forward the array so that
2281 			 * hopefully when more data comes in to fill it up
2282 			 * we will be able to slide it forward. Really I
2283 			 * don't think this should happen :-0
2284 			 */
2285 
2286 #ifdef SCTP_MAP_LOGGING
2287 			sctp_log_map((uint32_t) distance, (uint32_t) slide_from,
2288 			    (uint32_t) asoc->mapping_array_size,
2289 			    SCTP_MAP_SLIDE_NONE);
2290 #endif
2291 		} else {
2292 			int ii;
2293 
2294 			for (ii = 0; ii < distance; ii++) {
2295 				asoc->mapping_array[ii] =
2296 				    asoc->mapping_array[slide_from + ii];
2297 			}
2298 			for (ii = distance; ii <= slide_end; ii++) {
2299 				asoc->mapping_array[ii] = 0;
2300 			}
2301 			asoc->mapping_array_base_tsn += (slide_from << 3);
2302 #ifdef SCTP_MAP_LOGGING
2303 			sctp_log_map(asoc->mapping_array_base_tsn,
2304 			    asoc->cumulative_tsn, asoc->highest_tsn_inside_map,
2305 			    SCTP_MAP_SLIDE_RESULT);
2306 #endif
2307 		}
2308 	}
2309 	/* check the special flag for stream resets */
2310 	if (((liste = TAILQ_FIRST(&asoc->resetHead)) != NULL) &&
2311 	    ((compare_with_wrap(asoc->cumulative_tsn, liste->tsn, MAX_TSN)) ||
2312 	    (asoc->cumulative_tsn == liste->tsn))
2313 	    ) {
2314 		/*
2315 		 * we have finished working through the backlogged TSN's now
2316 		 * time to reset streams. 1: call reset function. 2: free
2317 		 * pending_reply space 3: distribute any chunks in
2318 		 * pending_reply_queue.
2319 		 */
2320 		struct sctp_queued_to_read *ctl;
2321 
2322 		sctp_reset_in_stream(stcb, liste->number_entries, liste->req.list_of_streams);
2323 		TAILQ_REMOVE(&asoc->resetHead, liste, next_resp);
2324 		SCTP_FREE(liste);
2325 		liste = TAILQ_FIRST(&asoc->resetHead);
2326 		ctl = TAILQ_FIRST(&asoc->pending_reply_queue);
2327 		if (ctl && (liste == NULL)) {
2328 			/* All can be removed */
2329 			while (ctl) {
2330 				TAILQ_REMOVE(&asoc->pending_reply_queue, ctl, next);
2331 				sctp_queue_data_to_stream(stcb, asoc, ctl, abort_flag);
2332 				if (*abort_flag) {
2333 					return;
2334 				}
2335 				ctl = TAILQ_FIRST(&asoc->pending_reply_queue);
2336 			}
2337 		} else if (ctl) {
2338 			/* more than one in queue */
2339 			while (!compare_with_wrap(ctl->sinfo_tsn, liste->tsn, MAX_TSN)) {
2340 				/*
2341 				 * if ctl->sinfo_tsn is <= liste->tsn we can
2342 				 * process it which is the NOT of
2343 				 * ctl->sinfo_tsn > liste->tsn
2344 				 */
2345 				TAILQ_REMOVE(&asoc->pending_reply_queue, ctl, next);
2346 				sctp_queue_data_to_stream(stcb, asoc, ctl, abort_flag);
2347 				if (*abort_flag) {
2348 					return;
2349 				}
2350 				ctl = TAILQ_FIRST(&asoc->pending_reply_queue);
2351 			}
2352 		}
2353 		/*
2354 		 * Now service re-assembly to pick up anything that has been
2355 		 * held on reassembly queue?
2356 		 */
2357 		sctp_deliver_reasm_check(stcb, asoc);
2358 	}
2359 	/*
2360 	 * Now we need to see if we need to queue a sack or just start the
2361 	 * timer (if allowed).
2362 	 */
2363 	if (ok_to_sack) {
2364 		if (SCTP_GET_STATE(asoc) == SCTP_STATE_SHUTDOWN_SENT) {
2365 			/*
2366 			 * Ok special case, in SHUTDOWN-SENT case. here we
2367 			 * maker sure SACK timer is off and instead send a
2368 			 * SHUTDOWN and a SACK
2369 			 */
2370 			if (callout_pending(&stcb->asoc.dack_timer.timer)) {
2371 				sctp_timer_stop(SCTP_TIMER_TYPE_RECV,
2372 				    stcb->sctp_ep, stcb, NULL, SCTP_FROM_SCTP_INDATA + SCTP_LOC_18);
2373 			}
2374 			sctp_send_shutdown(stcb, stcb->asoc.primary_destination);
2375 			sctp_send_sack(stcb);
2376 		} else {
2377 			int is_a_gap;
2378 
2379 			/* is there a gap now ? */
2380 			is_a_gap = compare_with_wrap(stcb->asoc.highest_tsn_inside_map,
2381 			    stcb->asoc.cumulative_tsn, MAX_TSN);
2382 
2383 			/*
2384 			 * CMT DAC algorithm: increase number of packets
2385 			 * received since last ack
2386 			 */
2387 			stcb->asoc.cmt_dac_pkts_rcvd++;
2388 
2389 			if ((stcb->asoc.first_ack_sent == 0) ||	/* First time we send a
2390 								 * sack */
2391 			    ((was_a_gap) && (is_a_gap == 0)) ||	/* was a gap, but no
2392 								 * longer is one */
2393 			    (stcb->asoc.numduptsns) ||	/* we have dup's */
2394 			    (is_a_gap) ||	/* is still a gap */
2395 			    (stcb->asoc.delayed_ack == 0) ||
2396 			    (callout_pending(&stcb->asoc.dack_timer.timer))	/* timer was up . second
2397 										 * packet */
2398 			    ) {
2399 
2400 				if ((sctp_cmt_on_off) && (sctp_cmt_use_dac) &&
2401 				    (stcb->asoc.first_ack_sent == 1) &&
2402 				    (stcb->asoc.numduptsns == 0) &&
2403 				    (stcb->asoc.delayed_ack) &&
2404 				    (!callout_pending(&stcb->asoc.dack_timer.timer))) {
2405 
2406 					/*
2407 					 * CMT DAC algorithm: With CMT,
2408 					 * delay acks even in the face of
2409 					 *
2410 					 * reordering. Therefore, if acks that
2411 					 * do not have to be sent because of
2412 					 * the above reasons, will be
2413 					 * delayed. That is, acks that would
2414 					 * have been sent due to gap reports
2415 					 * will be delayed with DAC. Start
2416 					 * the delayed ack timer.
2417 					 */
2418 					sctp_timer_start(SCTP_TIMER_TYPE_RECV,
2419 					    stcb->sctp_ep, stcb, NULL);
2420 				} else {
2421 					/*
2422 					 * Ok we must build a SACK since the
2423 					 * timer is pending, we got our
2424 					 * first packet OR there are gaps or
2425 					 * duplicates.
2426 					 */
2427 					stcb->asoc.first_ack_sent = 1;
2428 
2429 					sctp_send_sack(stcb);
2430 					/* The sending will stop the timer */
2431 				}
2432 			} else {
2433 				sctp_timer_start(SCTP_TIMER_TYPE_RECV,
2434 				    stcb->sctp_ep, stcb, NULL);
2435 			}
2436 		}
2437 	}
2438 }
2439 
2440 void
2441 sctp_service_queues(struct sctp_tcb *stcb, struct sctp_association *asoc)
2442 {
2443 	struct sctp_tmit_chunk *chk;
2444 	uint32_t tsize;
2445 	uint16_t nxt_todel;
2446 
2447 	if (asoc->fragmented_delivery_inprogress) {
2448 		sctp_service_reassembly(stcb, asoc);
2449 	}
2450 	/* Can we proceed further, i.e. the PD-API is complete */
2451 	if (asoc->fragmented_delivery_inprogress) {
2452 		/* no */
2453 		return;
2454 	}
2455 	/*
2456 	 * Now is there some other chunk I can deliver from the reassembly
2457 	 * queue.
2458 	 */
2459 	chk = TAILQ_FIRST(&asoc->reasmqueue);
2460 	if (chk == NULL) {
2461 		asoc->size_on_reasm_queue = 0;
2462 		asoc->cnt_on_reasm_queue = 0;
2463 		return;
2464 	}
2465 	nxt_todel = asoc->strmin[chk->rec.data.stream_number].last_sequence_delivered + 1;
2466 	if ((chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG) &&
2467 	    ((nxt_todel == chk->rec.data.stream_seq) ||
2468 	    (chk->rec.data.rcv_flags & SCTP_DATA_UNORDERED))) {
2469 		/*
2470 		 * Yep the first one is here. We setup to start reception,
2471 		 * by backing down the TSN just in case we can't deliver.
2472 		 */
2473 
2474 		/*
2475 		 * Before we start though either all of the message should
2476 		 * be here or 1/4 the socket buffer max or nothing on the
2477 		 * delivery queue and something can be delivered.
2478 		 */
2479 		if ((sctp_is_all_msg_on_reasm(asoc, &tsize) ||
2480 		    (tsize > stcb->sctp_ep->partial_delivery_point))) {
2481 			asoc->fragmented_delivery_inprogress = 1;
2482 			asoc->tsn_last_delivered = chk->rec.data.TSN_seq - 1;
2483 			asoc->str_of_pdapi = chk->rec.data.stream_number;
2484 			asoc->ssn_of_pdapi = chk->rec.data.stream_seq;
2485 			asoc->pdapi_ppid = chk->rec.data.payloadtype;
2486 			asoc->fragment_flags = chk->rec.data.rcv_flags;
2487 			sctp_service_reassembly(stcb, asoc);
2488 		}
2489 	}
2490 }
2491 
2492 extern int sctp_strict_data_order;
2493 
2494 int
2495 sctp_process_data(struct mbuf **mm, int iphlen, int *offset, int length,
2496     struct sctphdr *sh, struct sctp_inpcb *inp, struct sctp_tcb *stcb,
2497     struct sctp_nets *net, uint32_t * high_tsn)
2498 {
2499 	struct sctp_data_chunk *ch, chunk_buf;
2500 	struct sctp_association *asoc;
2501 	int num_chunks = 0;	/* number of control chunks processed */
2502 	int stop_proc = 0;
2503 	int chk_length, break_flag, last_chunk;
2504 	int abort_flag = 0, was_a_gap = 0;
2505 	struct mbuf *m;
2506 
2507 	/* set the rwnd */
2508 	sctp_set_rwnd(stcb, &stcb->asoc);
2509 
2510 	m = *mm;
2511 	SCTP_TCB_LOCK_ASSERT(stcb);
2512 	asoc = &stcb->asoc;
2513 	if ((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) ||
2514 	    (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_ALLGONE) ||
2515 	    (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET)) {
2516 		/*
2517 		 * wait a minute, this guy is gone, there is no longer a
2518 		 * receiver. Send peer an ABORT!
2519 		 */
2520 		struct mbuf *op_err;
2521 
2522 		op_err = sctp_generate_invmanparam(SCTP_CAUSE_OUT_OF_RESC);
2523 		sctp_abort_an_association(stcb->sctp_ep, stcb, 0, op_err);
2524 		return (2);
2525 	}
2526 	if (compare_with_wrap(stcb->asoc.highest_tsn_inside_map,
2527 	    stcb->asoc.cumulative_tsn, MAX_TSN)) {
2528 		/* there was a gap before this data was processed */
2529 		was_a_gap = 1;
2530 	}
2531 	/*
2532 	 * setup where we got the last DATA packet from for any SACK that
2533 	 * may need to go out. Don't bump the net. This is done ONLY when a
2534 	 * chunk is assigned.
2535 	 */
2536 	asoc->last_data_chunk_from = net;
2537 
2538 	/*
2539 	 * Now before we proceed we must figure out if this is a wasted
2540 	 * cluster... i.e. it is a small packet sent in and yet the driver
2541 	 * underneath allocated a full cluster for it. If so we must copy it
2542 	 * to a smaller mbuf and free up the cluster mbuf. This will help
2543 	 * with cluster starvation.
2544 	 */
2545 	if (m->m_len < (long)MHLEN && m->m_next == NULL) {
2546 		/* we only handle mbufs that are singletons.. not chains */
2547 		m = sctp_get_mbuf_for_msg(m->m_len, 1, M_DONTWAIT, 1, MT_DATA);
2548 		if (m) {
2549 			/* ok lets see if we can copy the data up */
2550 			caddr_t *from, *to;
2551 
2552 			if ((*mm)->m_flags & M_PKTHDR) {
2553 				/* got to copy the header first */
2554 				M_MOVE_PKTHDR(m, (*mm));
2555 			}
2556 			/* get the pointers and copy */
2557 			to = mtod(m, caddr_t *);
2558 			from = mtod((*mm), caddr_t *);
2559 			memcpy(to, from, (*mm)->m_len);
2560 			/* copy the length and free up the old */
2561 			m->m_len = (*mm)->m_len;
2562 			sctp_m_freem(*mm);
2563 			/* sucess, back copy */
2564 			*mm = m;
2565 		} else {
2566 			/* We are in trouble in the mbuf world .. yikes */
2567 			m = *mm;
2568 		}
2569 	}
2570 	/* get pointer to the first chunk header */
2571 	ch = (struct sctp_data_chunk *)sctp_m_getptr(m, *offset,
2572 	    sizeof(struct sctp_data_chunk), (uint8_t *) & chunk_buf);
2573 	if (ch == NULL) {
2574 		return (1);
2575 	}
2576 	/*
2577 	 * process all DATA chunks...
2578 	 */
2579 	*high_tsn = asoc->cumulative_tsn;
2580 	break_flag = 0;
2581 	while (stop_proc == 0) {
2582 		/* validate chunk length */
2583 		chk_length = ntohs(ch->ch.chunk_length);
2584 		if (length - *offset < chk_length) {
2585 			/* all done, mutulated chunk */
2586 			stop_proc = 1;
2587 			break;
2588 		}
2589 		if (ch->ch.chunk_type == SCTP_DATA) {
2590 			if ((size_t)chk_length < sizeof(struct sctp_data_chunk) + 1) {
2591 				/*
2592 				 * Need to send an abort since we had a
2593 				 * invalid data chunk.
2594 				 */
2595 				struct mbuf *op_err;
2596 
2597 				op_err = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
2598 				    0, M_DONTWAIT, 1, MT_DATA);
2599 
2600 				if (op_err) {
2601 					struct sctp_paramhdr *ph;
2602 					uint32_t *ippp;
2603 
2604 					op_err->m_len = sizeof(struct sctp_paramhdr) +
2605 					    (2 * sizeof(uint32_t));
2606 					ph = mtod(op_err, struct sctp_paramhdr *);
2607 					ph->param_type =
2608 					    htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
2609 					ph->param_length = htons(op_err->m_len);
2610 					ippp = (uint32_t *) (ph + 1);
2611 					*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_19);
2612 					ippp++;
2613 					*ippp = asoc->cumulative_tsn;
2614 
2615 				}
2616 				stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_19;
2617 				sctp_abort_association(inp, stcb, m, iphlen, sh,
2618 				    op_err);
2619 				return (2);
2620 			}
2621 #ifdef SCTP_AUDITING_ENABLED
2622 			sctp_audit_log(0xB1, 0);
2623 #endif
2624 			if (SCTP_SIZE32(chk_length) == (length - *offset)) {
2625 				last_chunk = 1;
2626 			} else {
2627 				last_chunk = 0;
2628 			}
2629 			if (sctp_process_a_data_chunk(stcb, asoc, mm, *offset, ch,
2630 			    chk_length, net, high_tsn, &abort_flag, &break_flag,
2631 			    last_chunk)) {
2632 				num_chunks++;
2633 			}
2634 			if (abort_flag)
2635 				return (2);
2636 
2637 			if (break_flag) {
2638 				/*
2639 				 * Set because of out of rwnd space and no
2640 				 * drop rep space left.
2641 				 */
2642 				stop_proc = 1;
2643 				break;
2644 			}
2645 		} else {
2646 			/* not a data chunk in the data region */
2647 			switch (ch->ch.chunk_type) {
2648 			case SCTP_INITIATION:
2649 			case SCTP_INITIATION_ACK:
2650 			case SCTP_SELECTIVE_ACK:
2651 			case SCTP_HEARTBEAT_REQUEST:
2652 			case SCTP_HEARTBEAT_ACK:
2653 			case SCTP_ABORT_ASSOCIATION:
2654 			case SCTP_SHUTDOWN:
2655 			case SCTP_SHUTDOWN_ACK:
2656 			case SCTP_OPERATION_ERROR:
2657 			case SCTP_COOKIE_ECHO:
2658 			case SCTP_COOKIE_ACK:
2659 			case SCTP_ECN_ECHO:
2660 			case SCTP_ECN_CWR:
2661 			case SCTP_SHUTDOWN_COMPLETE:
2662 			case SCTP_AUTHENTICATION:
2663 			case SCTP_ASCONF_ACK:
2664 			case SCTP_PACKET_DROPPED:
2665 			case SCTP_STREAM_RESET:
2666 			case SCTP_FORWARD_CUM_TSN:
2667 			case SCTP_ASCONF:
2668 				/*
2669 				 * Now, what do we do with KNOWN chunks that
2670 				 * are NOT in the right place?
2671 				 *
2672 				 * For now, I do nothing but ignore them. We
2673 				 * may later want to add sysctl stuff to
2674 				 * switch out and do either an ABORT() or
2675 				 * possibly process them.
2676 				 */
2677 				if (sctp_strict_data_order) {
2678 					struct mbuf *op_err;
2679 
2680 					op_err = sctp_generate_invmanparam(SCTP_CAUSE_PROTOCOL_VIOLATION);
2681 					sctp_abort_association(inp, stcb, m, iphlen, sh, op_err);
2682 					return (2);
2683 				}
2684 				break;
2685 			default:
2686 				/* unknown chunk type, use bit rules */
2687 				if (ch->ch.chunk_type & 0x40) {
2688 					/* Add a error report to the queue */
2689 					struct mbuf *mm;
2690 					struct sctp_paramhdr *phd;
2691 
2692 					mm = sctp_get_mbuf_for_msg(sizeof(*phd), 1, M_DONTWAIT, 1, MT_DATA);
2693 					if (mm) {
2694 						phd = mtod(mm, struct sctp_paramhdr *);
2695 						/*
2696 						 * We cheat and use param
2697 						 * type since we did not
2698 						 * bother to define a error
2699 						 * cause struct. They are
2700 						 * the same basic format
2701 						 * with different names.
2702 						 */
2703 						phd->param_type =
2704 						    htons(SCTP_CAUSE_UNRECOG_CHUNK);
2705 						phd->param_length =
2706 						    htons(chk_length + sizeof(*phd));
2707 						mm->m_len = sizeof(*phd);
2708 						mm->m_next = sctp_m_copym(m, *offset,
2709 						    SCTP_SIZE32(chk_length),
2710 						    M_DONTWAIT);
2711 						if (mm->m_next) {
2712 							mm->m_pkthdr.len =
2713 							    SCTP_SIZE32(chk_length) +
2714 							    sizeof(*phd);
2715 							sctp_queue_op_err(stcb, mm);
2716 						} else {
2717 							sctp_m_freem(mm);
2718 						}
2719 					}
2720 				}
2721 				if ((ch->ch.chunk_type & 0x80) == 0) {
2722 					/* discard the rest of this packet */
2723 					stop_proc = 1;
2724 				}	/* else skip this bad chunk and
2725 					 * continue... */
2726 				break;
2727 			};	/* switch of chunk type */
2728 		}
2729 		*offset += SCTP_SIZE32(chk_length);
2730 		if ((*offset >= length) || stop_proc) {
2731 			/* no more data left in the mbuf chain */
2732 			stop_proc = 1;
2733 			continue;
2734 		}
2735 		ch = (struct sctp_data_chunk *)sctp_m_getptr(m, *offset,
2736 		    sizeof(struct sctp_data_chunk), (uint8_t *) & chunk_buf);
2737 		if (ch == NULL) {
2738 			*offset = length;
2739 			stop_proc = 1;
2740 			break;
2741 
2742 		}
2743 	}			/* while */
2744 	if (break_flag) {
2745 		/*
2746 		 * we need to report rwnd overrun drops.
2747 		 */
2748 		sctp_send_packet_dropped(stcb, net, *mm, iphlen, 0);
2749 	}
2750 	if (num_chunks) {
2751 		/*
2752 		 * Did we get data, if so update the time for auto-close and
2753 		 * give peer credit for being alive.
2754 		 */
2755 		SCTP_STAT_INCR(sctps_recvpktwithdata);
2756 		stcb->asoc.overall_error_count = 0;
2757 		SCTP_GETTIME_TIMEVAL(&stcb->asoc.time_last_rcvd);
2758 	}
2759 	/* now service all of the reassm queue if needed */
2760 	if (!(TAILQ_EMPTY(&asoc->reasmqueue)))
2761 		sctp_service_queues(stcb, asoc);
2762 
2763 	if (SCTP_GET_STATE(asoc) == SCTP_STATE_SHUTDOWN_SENT) {
2764 		/*
2765 		 * Assure that we ack right away by making sure that a d-ack
2766 		 * timer is running. So the sack_check will send a sack.
2767 		 */
2768 		sctp_timer_start(SCTP_TIMER_TYPE_RECV, stcb->sctp_ep, stcb,
2769 		    net);
2770 	}
2771 	/* Start a sack timer or QUEUE a SACK for sending */
2772 	if ((stcb->asoc.cumulative_tsn == stcb->asoc.highest_tsn_inside_map) &&
2773 	    (stcb->asoc.first_ack_sent)) {
2774 		/* Everything is in order */
2775 		if (stcb->asoc.mapping_array[0] == 0xff) {
2776 			/* need to do the slide */
2777 			sctp_sack_check(stcb, 1, was_a_gap, &abort_flag);
2778 		} else {
2779 			if (callout_pending(&stcb->asoc.dack_timer.timer)) {
2780 				stcb->asoc.first_ack_sent = 1;
2781 				callout_stop(&stcb->asoc.dack_timer.timer);
2782 				sctp_send_sack(stcb);
2783 			} else {
2784 				sctp_timer_start(SCTP_TIMER_TYPE_RECV,
2785 				    stcb->sctp_ep, stcb, NULL);
2786 			}
2787 		}
2788 	} else {
2789 		sctp_sack_check(stcb, 1, was_a_gap, &abort_flag);
2790 	}
2791 	if (abort_flag)
2792 		return (2);
2793 
2794 	return (0);
2795 }
2796 
2797 static void
2798 sctp_handle_segments(struct sctp_tcb *stcb, struct sctp_association *asoc,
2799     struct sctp_sack_chunk *ch, uint32_t last_tsn, uint32_t * biggest_tsn_acked,
2800     uint32_t * biggest_newly_acked_tsn, uint32_t * this_sack_lowest_newack, int num_seg, int *ecn_seg_sums)
2801 {
2802 	/************************************************/
2803 	/* process fragments and update sendqueue        */
2804 	/************************************************/
2805 	struct sctp_sack *sack;
2806 	struct sctp_gap_ack_block *frag;
2807 	struct sctp_tmit_chunk *tp1;
2808 	int i;
2809 	unsigned int j;
2810 
2811 #ifdef SCTP_FR_LOGGING
2812 	int num_frs = 0;
2813 
2814 #endif
2815 	uint16_t frag_strt, frag_end, primary_flag_set;
2816 	u_long last_frag_high;
2817 
2818 	/*
2819 	 * @@@ JRI : TODO: This flag is not used anywhere .. remove?
2820 	 */
2821 	if (asoc->primary_destination->dest_state & SCTP_ADDR_SWITCH_PRIMARY) {
2822 		primary_flag_set = 1;
2823 	} else {
2824 		primary_flag_set = 0;
2825 	}
2826 
2827 	sack = &ch->sack;
2828 	frag = (struct sctp_gap_ack_block *)((caddr_t)sack +
2829 	    sizeof(struct sctp_sack));
2830 	tp1 = NULL;
2831 	last_frag_high = 0;
2832 	for (i = 0; i < num_seg; i++) {
2833 		frag_strt = ntohs(frag->start);
2834 		frag_end = ntohs(frag->end);
2835 		/* some sanity checks on the fargment offsets */
2836 		if (frag_strt > frag_end) {
2837 			/* this one is malformed, skip */
2838 			frag++;
2839 			continue;
2840 		}
2841 		if (compare_with_wrap((frag_end + last_tsn), *biggest_tsn_acked,
2842 		    MAX_TSN))
2843 			*biggest_tsn_acked = frag_end + last_tsn;
2844 
2845 		/* mark acked dgs and find out the highestTSN being acked */
2846 		if (tp1 == NULL) {
2847 			tp1 = TAILQ_FIRST(&asoc->sent_queue);
2848 
2849 			/* save the locations of the last frags */
2850 			last_frag_high = frag_end + last_tsn;
2851 		} else {
2852 			/*
2853 			 * now lets see if we need to reset the queue due to
2854 			 * a out-of-order SACK fragment
2855 			 */
2856 			if (compare_with_wrap(frag_strt + last_tsn,
2857 			    last_frag_high, MAX_TSN)) {
2858 				/*
2859 				 * if the new frag starts after the last TSN
2860 				 * frag covered, we are ok and this one is
2861 				 * beyond the last one
2862 				 */
2863 				;
2864 			} else {
2865 				/*
2866 				 * ok, they have reset us, so we need to
2867 				 * reset the queue this will cause extra
2868 				 * hunting but hey, they chose the
2869 				 * performance hit when they failed to order
2870 				 * there gaps..
2871 				 */
2872 				tp1 = TAILQ_FIRST(&asoc->sent_queue);
2873 			}
2874 			last_frag_high = frag_end + last_tsn;
2875 		}
2876 		for (j = frag_strt + last_tsn; j <= frag_end + last_tsn; j++) {
2877 			while (tp1) {
2878 #ifdef SCTP_FR_LOGGING
2879 				if (tp1->rec.data.doing_fast_retransmit)
2880 					num_frs++;
2881 #endif
2882 
2883 				/*
2884 				 * CMT: CUCv2 algorithm. For each TSN being
2885 				 * processed from the sent queue, track the
2886 				 * next expected pseudo-cumack, or
2887 				 * rtx_pseudo_cumack, if required. Separate
2888 				 * cumack trackers for first transmissions,
2889 				 * and retransmissions.
2890 				 */
2891 				if ((tp1->whoTo->find_pseudo_cumack == 1) && (tp1->sent < SCTP_DATAGRAM_RESEND) &&
2892 				    (tp1->snd_count == 1)) {
2893 					tp1->whoTo->pseudo_cumack = tp1->rec.data.TSN_seq;
2894 					tp1->whoTo->find_pseudo_cumack = 0;
2895 				}
2896 				if ((tp1->whoTo->find_rtx_pseudo_cumack == 1) && (tp1->sent < SCTP_DATAGRAM_RESEND) &&
2897 				    (tp1->snd_count > 1)) {
2898 					tp1->whoTo->rtx_pseudo_cumack = tp1->rec.data.TSN_seq;
2899 					tp1->whoTo->find_rtx_pseudo_cumack = 0;
2900 				}
2901 				if (tp1->rec.data.TSN_seq == j) {
2902 					if (tp1->sent != SCTP_DATAGRAM_UNSENT) {
2903 						/*
2904 						 * must be held until
2905 						 * cum-ack passes
2906 						 */
2907 						/*
2908 						 * ECN Nonce: Add the nonce
2909 						 * value to the sender's
2910 						 * nonce sum
2911 						 */
2912 						if (tp1->sent < SCTP_DATAGRAM_ACKED) {
2913 							/*
2914 							 * If it is less
2915 							 * than ACKED, it is
2916 							 * now no-longer in
2917 							 * flight. Higher
2918 							 * values may
2919 							 * already be set
2920 							 * via previous Gap
2921 							 * Ack Blocks...
2922 							 * i.e. ACKED or
2923 							 * MARKED.
2924 							 */
2925 							if (compare_with_wrap(tp1->rec.data.TSN_seq,
2926 							    *biggest_newly_acked_tsn, MAX_TSN)) {
2927 								*biggest_newly_acked_tsn = tp1->rec.data.TSN_seq;
2928 							}
2929 							/*
2930 							 * CMT: SFR algo
2931 							 * (and HTNA) - set
2932 							 * saw_newack to 1
2933 							 * for dest being
2934 							 * newly acked.
2935 							 * update
2936 							 * this_sack_highest_
2937 							 * n ewack if
2938 							 * appropriate.
2939 							 */
2940 							if (tp1->rec.data.chunk_was_revoked == 0)
2941 								tp1->whoTo->saw_newack = 1;
2942 
2943 							if (compare_with_wrap(tp1->rec.data.TSN_seq,
2944 							    tp1->whoTo->this_sack_highest_newack,
2945 							    MAX_TSN)) {
2946 								tp1->whoTo->this_sack_highest_newack =
2947 								    tp1->rec.data.TSN_seq;
2948 							}
2949 							/*
2950 							 * CMT DAC algo:
2951 							 * also update
2952 							 * this_sack_lowest_n
2953 							 * e wack
2954 							 */
2955 							if (*this_sack_lowest_newack == 0) {
2956 #ifdef SCTP_SACK_LOGGING
2957 								sctp_log_sack(*this_sack_lowest_newack,
2958 								    last_tsn,
2959 								    tp1->rec.data.TSN_seq,
2960 								    0,
2961 								    0,
2962 								    SCTP_LOG_TSN_ACKED);
2963 #endif
2964 								*this_sack_lowest_newack = tp1->rec.data.TSN_seq;
2965 							}
2966 							/*
2967 							 * CMT: CUCv2
2968 							 * algorithm. If
2969 							 * (rtx-)pseudo-cumac
2970 							 * k for corresp
2971 							 * dest is being
2972 							 * acked, then we
2973 							 * have a new
2974 							 * (rtx-)pseudo-cumac
2975 							 * k . Set
2976 							 * new_(rtx_)pseudo_c
2977 							 * u mack to TRUE so
2978 							 * that the cwnd for
2979 							 * this dest can be
2980 							 * updated. Also
2981 							 * trigger search
2982 							 * for the next
2983 							 * expected
2984 							 * (rtx-)pseudo-cumac
2985 							 * k . Separate
2986 							 * pseudo_cumack
2987 							 * trackers for
2988 							 * first
2989 							 * transmissions and
2990 							 * retransmissions.
2991 							 */
2992 							if (tp1->rec.data.TSN_seq == tp1->whoTo->pseudo_cumack) {
2993 								if (tp1->rec.data.chunk_was_revoked == 0) {
2994 									tp1->whoTo->new_pseudo_cumack = 1;
2995 								}
2996 								tp1->whoTo->find_pseudo_cumack = 1;
2997 							}
2998 #ifdef SCTP_CWND_LOGGING
2999 							sctp_log_cwnd(stcb, tp1->whoTo, tp1->rec.data.TSN_seq, SCTP_CWND_LOG_FROM_SACK);
3000 #endif
3001 							if (tp1->rec.data.TSN_seq == tp1->whoTo->rtx_pseudo_cumack) {
3002 								if (tp1->rec.data.chunk_was_revoked == 0) {
3003 									tp1->whoTo->new_pseudo_cumack = 1;
3004 								}
3005 								tp1->whoTo->find_rtx_pseudo_cumack = 1;
3006 							}
3007 #ifdef SCTP_SACK_LOGGING
3008 							sctp_log_sack(*biggest_newly_acked_tsn,
3009 							    last_tsn,
3010 							    tp1->rec.data.TSN_seq,
3011 							    frag_strt,
3012 							    frag_end,
3013 							    SCTP_LOG_TSN_ACKED);
3014 #endif
3015 #ifdef SCTP_FLIGHT_LOGGING
3016 							sctp_misc_ints(SCTP_FLIGHT_LOG_DOWN,
3017 							    tp1->whoTo->flight_size,
3018 							    tp1->book_size,
3019 							    (uintptr_t) stcb,
3020 							    tp1->rec.data.TSN_seq);
3021 #endif
3022 							if (tp1->whoTo->flight_size >= tp1->book_size)
3023 								tp1->whoTo->flight_size -= tp1->book_size;
3024 							else
3025 								tp1->whoTo->flight_size = 0;
3026 							if (asoc->total_flight >= tp1->book_size) {
3027 								asoc->total_flight -= tp1->book_size;
3028 								if (asoc->total_flight_count > 0)
3029 									asoc->total_flight_count--;
3030 							} else {
3031 								asoc->total_flight = 0;
3032 								asoc->total_flight_count = 0;
3033 							}
3034 
3035 							tp1->whoTo->net_ack += tp1->send_size;
3036 
3037 							if (tp1->snd_count < 2) {
3038 								/*
3039 								 * True
3040 								 * non-retran
3041 								 * smited
3042 								 * chunk */
3043 								tp1->whoTo->net_ack2 += tp1->send_size;
3044 
3045 								/*
3046 								 * update RTO
3047 								 * too ? */
3048 								if (tp1->do_rtt) {
3049 									tp1->whoTo->RTO =
3050 									    sctp_calculate_rto(stcb,
3051 									    asoc,
3052 									    tp1->whoTo,
3053 									    &tp1->sent_rcv_time);
3054 									tp1->whoTo->rto_pending = 0;
3055 									tp1->do_rtt = 0;
3056 								}
3057 							}
3058 						}
3059 						if (tp1->sent <= SCTP_DATAGRAM_RESEND &&
3060 						    tp1->sent != SCTP_DATAGRAM_UNSENT &&
3061 						    compare_with_wrap(tp1->rec.data.TSN_seq,
3062 						    asoc->this_sack_highest_gap,
3063 						    MAX_TSN)) {
3064 							asoc->this_sack_highest_gap =
3065 							    tp1->rec.data.TSN_seq;
3066 						}
3067 						if (tp1->sent == SCTP_DATAGRAM_RESEND) {
3068 							sctp_ucount_decr(asoc->sent_queue_retran_cnt);
3069 #ifdef SCTP_AUDITING_ENABLED
3070 							sctp_audit_log(0xB2,
3071 							    (asoc->sent_queue_retran_cnt & 0x000000ff));
3072 #endif
3073 
3074 						}
3075 						(*ecn_seg_sums) += tp1->rec.data.ect_nonce;
3076 						(*ecn_seg_sums) &= SCTP_SACK_NONCE_SUM;
3077 
3078 						tp1->sent = SCTP_DATAGRAM_MARKED;
3079 					}
3080 					break;
3081 				}	/* if (tp1->TSN_seq == j) */
3082 				if (compare_with_wrap(tp1->rec.data.TSN_seq, j,
3083 				    MAX_TSN))
3084 					break;
3085 
3086 				tp1 = TAILQ_NEXT(tp1, sctp_next);
3087 			}	/* end while (tp1) */
3088 		}		/* end for (j = fragStart */
3089 		frag++;		/* next one */
3090 	}
3091 #ifdef SCTP_FR_LOGGING
3092 	/*
3093 	 * if (num_frs) sctp_log_fr(*biggest_tsn_acked,
3094 	 * *biggest_newly_acked_tsn, last_tsn, SCTP_FR_LOG_BIGGEST_TSNS);
3095 	 */
3096 #endif
3097 }
3098 
3099 static void
3100 sctp_check_for_revoked(struct sctp_association *asoc, uint32_t cumack,
3101     u_long biggest_tsn_acked)
3102 {
3103 	struct sctp_tmit_chunk *tp1;
3104 	int tot_revoked = 0;
3105 
3106 	tp1 = TAILQ_FIRST(&asoc->sent_queue);
3107 	while (tp1) {
3108 		if (compare_with_wrap(tp1->rec.data.TSN_seq, cumack,
3109 		    MAX_TSN)) {
3110 			/*
3111 			 * ok this guy is either ACK or MARKED. If it is
3112 			 * ACKED it has been previously acked but not this
3113 			 * time i.e. revoked.  If it is MARKED it was ACK'ed
3114 			 * again.
3115 			 */
3116 			if (tp1->sent == SCTP_DATAGRAM_ACKED) {
3117 				/* it has been revoked */
3118 				tp1->sent = SCTP_DATAGRAM_SENT;
3119 				tp1->rec.data.chunk_was_revoked = 1;
3120 				/*
3121 				 * We must add this stuff back in to assure
3122 				 * timers and such get started.
3123 				 */
3124 				tp1->whoTo->flight_size += tp1->book_size;
3125 				asoc->total_flight_count++;
3126 				asoc->total_flight += tp1->book_size;
3127 				tot_revoked++;
3128 #ifdef SCTP_SACK_LOGGING
3129 				sctp_log_sack(asoc->last_acked_seq,
3130 				    cumack,
3131 				    tp1->rec.data.TSN_seq,
3132 				    0,
3133 				    0,
3134 				    SCTP_LOG_TSN_REVOKED);
3135 #endif
3136 			} else if (tp1->sent == SCTP_DATAGRAM_MARKED) {
3137 				/* it has been re-acked in this SACK */
3138 				tp1->sent = SCTP_DATAGRAM_ACKED;
3139 			}
3140 		}
3141 		if (tp1->sent == SCTP_DATAGRAM_UNSENT)
3142 			break;
3143 		tp1 = TAILQ_NEXT(tp1, sctp_next);
3144 	}
3145 	if (tot_revoked > 0) {
3146 		/*
3147 		 * Setup the ecn nonce re-sync point. We do this since once
3148 		 * data is revoked we begin to retransmit things, which do
3149 		 * NOT have the ECN bits set. This means we are now out of
3150 		 * sync and must wait until we get back in sync with the
3151 		 * peer to check ECN bits.
3152 		 */
3153 		tp1 = TAILQ_FIRST(&asoc->send_queue);
3154 		if (tp1 == NULL) {
3155 			asoc->nonce_resync_tsn = asoc->sending_seq;
3156 		} else {
3157 			asoc->nonce_resync_tsn = tp1->rec.data.TSN_seq;
3158 		}
3159 		asoc->nonce_wait_for_ecne = 0;
3160 		asoc->nonce_sum_check = 0;
3161 	}
3162 }
3163 
3164 extern int sctp_peer_chunk_oh;
3165 
3166 static void
3167 sctp_strike_gap_ack_chunks(struct sctp_tcb *stcb, struct sctp_association *asoc,
3168     u_long biggest_tsn_acked, u_long biggest_tsn_newly_acked, u_long this_sack_lowest_newack, int accum_moved)
3169 {
3170 	struct sctp_tmit_chunk *tp1;
3171 	int strike_flag = 0;
3172 	struct timeval now;
3173 	int tot_retrans = 0;
3174 	uint32_t sending_seq;
3175 	struct sctp_nets *net;
3176 	int num_dests_sacked = 0;
3177 
3178 	/*
3179 	 * select the sending_seq, this is either the next thing ready to be
3180 	 * sent but not transmitted, OR, the next seq we assign.
3181 	 */
3182 	tp1 = TAILQ_FIRST(&stcb->asoc.send_queue);
3183 	if (tp1 == NULL) {
3184 		sending_seq = asoc->sending_seq;
3185 	} else {
3186 		sending_seq = tp1->rec.data.TSN_seq;
3187 	}
3188 
3189 	/* CMT DAC algo: finding out if SACK is a mixed SACK */
3190 	if (sctp_cmt_on_off && sctp_cmt_use_dac) {
3191 		TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
3192 			if (net->saw_newack)
3193 				num_dests_sacked++;
3194 		}
3195 	}
3196 	if (stcb->asoc.peer_supports_prsctp) {
3197 		SCTP_GETTIME_TIMEVAL(&now);
3198 	}
3199 	tp1 = TAILQ_FIRST(&asoc->sent_queue);
3200 	while (tp1) {
3201 		strike_flag = 0;
3202 		if (tp1->no_fr_allowed) {
3203 			/* this one had a timeout or something */
3204 			tp1 = TAILQ_NEXT(tp1, sctp_next);
3205 			continue;
3206 		}
3207 #ifdef SCTP_FR_LOGGING
3208 		if (tp1->sent < SCTP_DATAGRAM_RESEND)
3209 			sctp_log_fr(biggest_tsn_newly_acked,
3210 			    tp1->rec.data.TSN_seq,
3211 			    tp1->sent,
3212 			    SCTP_FR_LOG_CHECK_STRIKE);
3213 #endif
3214 		if (compare_with_wrap(tp1->rec.data.TSN_seq, biggest_tsn_acked,
3215 		    MAX_TSN) ||
3216 		    tp1->sent == SCTP_DATAGRAM_UNSENT) {
3217 			/* done */
3218 			break;
3219 		}
3220 		if (stcb->asoc.peer_supports_prsctp) {
3221 			if ((PR_SCTP_TTL_ENABLED(tp1->flags)) && tp1->sent < SCTP_DATAGRAM_ACKED) {
3222 				/* Is it expired? */
3223 				if (timevalcmp(&now, &tp1->rec.data.timetodrop, >)) {
3224 					/* Yes so drop it */
3225 					if (tp1->data != NULL) {
3226 						sctp_release_pr_sctp_chunk(stcb, tp1,
3227 						    (SCTP_RESPONSE_TO_USER_REQ | SCTP_NOTIFY_DATAGRAM_SENT),
3228 						    &asoc->sent_queue);
3229 					}
3230 					tp1 = TAILQ_NEXT(tp1, sctp_next);
3231 					continue;
3232 				}
3233 			}
3234 			if ((PR_SCTP_RTX_ENABLED(tp1->flags)) && tp1->sent < SCTP_DATAGRAM_ACKED) {
3235 				/* Has it been retransmitted tv_sec times? */
3236 				if (tp1->snd_count > tp1->rec.data.timetodrop.tv_sec) {
3237 					/* Yes, so drop it */
3238 					if (tp1->data != NULL) {
3239 						sctp_release_pr_sctp_chunk(stcb, tp1,
3240 						    (SCTP_RESPONSE_TO_USER_REQ | SCTP_NOTIFY_DATAGRAM_SENT),
3241 						    &asoc->sent_queue);
3242 					}
3243 					tp1 = TAILQ_NEXT(tp1, sctp_next);
3244 					continue;
3245 				}
3246 			}
3247 		}
3248 		if (compare_with_wrap(tp1->rec.data.TSN_seq,
3249 		    asoc->this_sack_highest_gap, MAX_TSN)) {
3250 			/* we are beyond the tsn in the sack  */
3251 			break;
3252 		}
3253 		if (tp1->sent >= SCTP_DATAGRAM_RESEND) {
3254 			/* either a RESEND, ACKED, or MARKED */
3255 			/* skip */
3256 			tp1 = TAILQ_NEXT(tp1, sctp_next);
3257 			continue;
3258 		}
3259 		/*
3260 		 * CMT : SFR algo (covers part of DAC and HTNA as well)
3261 		 */
3262 		if (tp1->whoTo->saw_newack == 0) {
3263 			/*
3264 			 * No new acks were receieved for data sent to this
3265 			 * dest. Therefore, according to the SFR algo for
3266 			 * CMT, no data sent to this dest can be marked for
3267 			 * FR using this SACK. (iyengar@cis.udel.edu,
3268 			 * 2005/05/12)
3269 			 */
3270 			tp1 = TAILQ_NEXT(tp1, sctp_next);
3271 			continue;
3272 		} else if (compare_with_wrap(tp1->rec.data.TSN_seq,
3273 		    tp1->whoTo->this_sack_highest_newack, MAX_TSN)) {
3274 			/*
3275 			 * CMT: New acks were receieved for data sent to
3276 			 * this dest. But no new acks were seen for data
3277 			 * sent after tp1. Therefore, according to the SFR
3278 			 * algo for CMT, tp1 cannot be marked for FR using
3279 			 * this SACK. This step covers part of the DAC algo
3280 			 * and the HTNA algo as well.
3281 			 */
3282 			tp1 = TAILQ_NEXT(tp1, sctp_next);
3283 			continue;
3284 		}
3285 		/*
3286 		 * Here we check to see if we were have already done a FR
3287 		 * and if so we see if the biggest TSN we saw in the sack is
3288 		 * smaller than the recovery point. If so we don't strike
3289 		 * the tsn... otherwise we CAN strike the TSN.
3290 		 */
3291 		/*
3292 		 * @@@ JRI: Check for CMT
3293 		 */
3294 		if (accum_moved && asoc->fast_retran_loss_recovery && (sctp_cmt_on_off == 0)) {
3295 			/*
3296 			 * Strike the TSN if in fast-recovery and cum-ack
3297 			 * moved.
3298 			 */
3299 #ifdef SCTP_FR_LOGGING
3300 			sctp_log_fr(biggest_tsn_newly_acked,
3301 			    tp1->rec.data.TSN_seq,
3302 			    tp1->sent,
3303 			    SCTP_FR_LOG_STRIKE_CHUNK);
3304 #endif
3305 			tp1->sent++;
3306 			if (sctp_cmt_on_off && sctp_cmt_use_dac) {
3307 				/*
3308 				 * CMT DAC algorithm: If SACK flag is set to
3309 				 * 0, then lowest_newack test will not pass
3310 				 * because it would have been set to the
3311 				 * cumack earlier. If not already to be
3312 				 * rtx'd, If not a mixed sack and if tp1 is
3313 				 * not between two sacked TSNs, then mark by
3314 				 * one more.
3315 				 */
3316 				if ((tp1->sent != SCTP_DATAGRAM_RESEND) && (num_dests_sacked == 1) &&
3317 				    compare_with_wrap(this_sack_lowest_newack, tp1->rec.data.TSN_seq, MAX_TSN)) {
3318 #ifdef SCTP_FR_LOGGING
3319 					sctp_log_fr(16 + num_dests_sacked,
3320 					    tp1->rec.data.TSN_seq,
3321 					    tp1->sent,
3322 					    SCTP_FR_LOG_STRIKE_CHUNK);
3323 #endif
3324 					tp1->sent++;
3325 				}
3326 			}
3327 		} else if (tp1->rec.data.doing_fast_retransmit) {
3328 			/*
3329 			 * For those that have done a FR we must take
3330 			 * special consideration if we strike. I.e the
3331 			 * biggest_newly_acked must be higher than the
3332 			 * sending_seq at the time we did the FR.
3333 			 */
3334 #ifdef SCTP_FR_TO_ALTERNATE
3335 			/*
3336 			 * If FR's go to new networks, then we must only do
3337 			 * this for singly homed asoc's. However if the FR's
3338 			 * go to the same network (Armando's work) then its
3339 			 * ok to FR multiple times.
3340 			 */
3341 			if (asoc->numnets < 2)
3342 #else
3343 			if (1)
3344 #endif
3345 			{
3346 				if ((compare_with_wrap(biggest_tsn_newly_acked,
3347 				    tp1->rec.data.fast_retran_tsn, MAX_TSN)) ||
3348 				    (biggest_tsn_newly_acked ==
3349 				    tp1->rec.data.fast_retran_tsn)) {
3350 					/*
3351 					 * Strike the TSN, since this ack is
3352 					 * beyond where things were when we
3353 					 * did a FR.
3354 					 */
3355 #ifdef SCTP_FR_LOGGING
3356 					sctp_log_fr(biggest_tsn_newly_acked,
3357 					    tp1->rec.data.TSN_seq,
3358 					    tp1->sent,
3359 					    SCTP_FR_LOG_STRIKE_CHUNK);
3360 #endif
3361 					tp1->sent++;
3362 					strike_flag = 1;
3363 					if (sctp_cmt_on_off && sctp_cmt_use_dac) {
3364 						/*
3365 						 * CMT DAC algorithm: If
3366 						 * SACK flag is set to 0,
3367 						 * then lowest_newack test
3368 						 * will not pass because it
3369 						 * would have been set to
3370 						 * the cumack earlier. If
3371 						 * not already to be rtx'd,
3372 						 * If not a mixed sack and
3373 						 * if tp1 is not between two
3374 						 * sacked TSNs, then mark by
3375 						 * one more.
3376 						 */
3377 						if ((tp1->sent != SCTP_DATAGRAM_RESEND) && (num_dests_sacked == 1) &&
3378 						    compare_with_wrap(this_sack_lowest_newack, tp1->rec.data.TSN_seq, MAX_TSN)) {
3379 #ifdef SCTP_FR_LOGGING
3380 							sctp_log_fr(32 + num_dests_sacked,
3381 							    tp1->rec.data.TSN_seq,
3382 							    tp1->sent,
3383 							    SCTP_FR_LOG_STRIKE_CHUNK);
3384 #endif
3385 							tp1->sent++;
3386 						}
3387 					}
3388 				}
3389 			}
3390 			/*
3391 			 * @@@ JRI: TODO: remove code for HTNA algo. CMT's
3392 			 * SFR algo covers HTNA.
3393 			 */
3394 		} else if (compare_with_wrap(tp1->rec.data.TSN_seq,
3395 		    biggest_tsn_newly_acked, MAX_TSN)) {
3396 			/*
3397 			 * We don't strike these: This is the  HTNA
3398 			 * algorithm i.e. we don't strike If our TSN is
3399 			 * larger than the Highest TSN Newly Acked.
3400 			 */
3401 			;
3402 		} else {
3403 			/* Strike the TSN */
3404 #ifdef SCTP_FR_LOGGING
3405 			sctp_log_fr(biggest_tsn_newly_acked,
3406 			    tp1->rec.data.TSN_seq,
3407 			    tp1->sent,
3408 			    SCTP_FR_LOG_STRIKE_CHUNK);
3409 #endif
3410 			tp1->sent++;
3411 			if (sctp_cmt_on_off && sctp_cmt_use_dac) {
3412 				/*
3413 				 * CMT DAC algorithm: If SACK flag is set to
3414 				 * 0, then lowest_newack test will not pass
3415 				 * because it would have been set to the
3416 				 * cumack earlier. If not already to be
3417 				 * rtx'd, If not a mixed sack and if tp1 is
3418 				 * not between two sacked TSNs, then mark by
3419 				 * one more.
3420 				 */
3421 				if ((tp1->sent != SCTP_DATAGRAM_RESEND) && (num_dests_sacked == 1) &&
3422 				    compare_with_wrap(this_sack_lowest_newack, tp1->rec.data.TSN_seq, MAX_TSN)) {
3423 #ifdef SCTP_FR_LOGGING
3424 					sctp_log_fr(48 + num_dests_sacked,
3425 					    tp1->rec.data.TSN_seq,
3426 					    tp1->sent,
3427 					    SCTP_FR_LOG_STRIKE_CHUNK);
3428 #endif
3429 					tp1->sent++;
3430 				}
3431 			}
3432 		}
3433 		if (tp1->sent == SCTP_DATAGRAM_RESEND) {
3434 			/* Increment the count to resend */
3435 			struct sctp_nets *alt;
3436 
3437 			/* printf("OK, we are now ready to FR this guy\n"); */
3438 #ifdef SCTP_FR_LOGGING
3439 			sctp_log_fr(tp1->rec.data.TSN_seq, tp1->snd_count,
3440 			    0, SCTP_FR_MARKED);
3441 #endif
3442 			if (strike_flag) {
3443 				/* This is a subsequent FR */
3444 				SCTP_STAT_INCR(sctps_sendmultfastretrans);
3445 			}
3446 			sctp_ucount_incr(asoc->sent_queue_retran_cnt);
3447 
3448 			if (sctp_cmt_on_off) {
3449 				/*
3450 				 * CMT: Using RTX_SSTHRESH policy for CMT.
3451 				 * If CMT is being used, then pick dest with
3452 				 * largest ssthresh for any retransmission.
3453 				 * (iyengar@cis.udel.edu, 2005/08/12)
3454 				 */
3455 				tp1->no_fr_allowed = 1;
3456 				alt = tp1->whoTo;
3457 				alt = sctp_find_alternate_net(stcb, alt, 1);
3458 				/*
3459 				 * CUCv2: If a different dest is picked for
3460 				 * the retransmission, then new
3461 				 * (rtx-)pseudo_cumack needs to be tracked
3462 				 * for orig dest. Let CUCv2 track new (rtx-)
3463 				 * pseudo-cumack always.
3464 				 */
3465 				tp1->whoTo->find_pseudo_cumack = 1;
3466 				tp1->whoTo->find_rtx_pseudo_cumack = 1;
3467 
3468 
3469 			} else {/* CMT is OFF */
3470 
3471 #ifdef SCTP_FR_TO_ALTERNATE
3472 				/* Can we find an alternate? */
3473 				alt = sctp_find_alternate_net(stcb, tp1->whoTo, 0);
3474 #else
3475 				/*
3476 				 * default behavior is to NOT retransmit
3477 				 * FR's to an alternate. Armando Caro's
3478 				 * paper details why.
3479 				 */
3480 				alt = tp1->whoTo;
3481 #endif
3482 			}
3483 
3484 			tp1->rec.data.doing_fast_retransmit = 1;
3485 			tot_retrans++;
3486 			/* mark the sending seq for possible subsequent FR's */
3487 			/*
3488 			 * printf("Marking TSN for FR new value %x\n",
3489 			 * (uint32_t)tpi->rec.data.TSN_seq);
3490 			 */
3491 			if (TAILQ_EMPTY(&asoc->send_queue)) {
3492 				/*
3493 				 * If the queue of send is empty then its
3494 				 * the next sequence number that will be
3495 				 * assigned so we subtract one from this to
3496 				 * get the one we last sent.
3497 				 */
3498 				tp1->rec.data.fast_retran_tsn = sending_seq;
3499 			} else {
3500 				/*
3501 				 * If there are chunks on the send queue
3502 				 * (unsent data that has made it from the
3503 				 * stream queues but not out the door, we
3504 				 * take the first one (which will have the
3505 				 * lowest TSN) and subtract one to get the
3506 				 * one we last sent.
3507 				 */
3508 				struct sctp_tmit_chunk *ttt;
3509 
3510 				ttt = TAILQ_FIRST(&asoc->send_queue);
3511 				tp1->rec.data.fast_retran_tsn =
3512 				    ttt->rec.data.TSN_seq;
3513 			}
3514 
3515 			if (tp1->do_rtt) {
3516 				/*
3517 				 * this guy had a RTO calculation pending on
3518 				 * it, cancel it
3519 				 */
3520 				tp1->whoTo->rto_pending = 0;
3521 				tp1->do_rtt = 0;
3522 			}
3523 			/* fix counts and things */
3524 #ifdef SCTP_FLIGHT_LOGGING
3525 			sctp_misc_ints(SCTP_FLIGHT_LOG_DOWN,
3526 			    tp1->whoTo->flight_size,
3527 			    tp1->book_size,
3528 			    (uintptr_t) stcb,
3529 			    tp1->rec.data.TSN_seq);
3530 #endif
3531 			tp1->whoTo->net_ack++;
3532 			if (tp1->whoTo->flight_size >= tp1->book_size)
3533 				tp1->whoTo->flight_size -= tp1->book_size;
3534 			else
3535 				tp1->whoTo->flight_size = 0;
3536 
3537 #ifdef SCTP_LOG_RWND
3538 			sctp_log_rwnd(SCTP_INCREASE_PEER_RWND,
3539 			    asoc->peers_rwnd, tp1->send_size, sctp_peer_chunk_oh);
3540 #endif
3541 			/* add back to the rwnd */
3542 			asoc->peers_rwnd += (tp1->send_size + sctp_peer_chunk_oh);
3543 
3544 			/* remove from the total flight */
3545 			if (asoc->total_flight >= tp1->book_size) {
3546 				asoc->total_flight -= tp1->book_size;
3547 				if (asoc->total_flight_count > 0)
3548 					asoc->total_flight_count--;
3549 			} else {
3550 				asoc->total_flight = 0;
3551 				asoc->total_flight_count = 0;
3552 			}
3553 
3554 
3555 			if (alt != tp1->whoTo) {
3556 				/* yes, there is an alternate. */
3557 				sctp_free_remote_addr(tp1->whoTo);
3558 				tp1->whoTo = alt;
3559 				atomic_add_int(&alt->ref_count, 1);
3560 			}
3561 		}
3562 		tp1 = TAILQ_NEXT(tp1, sctp_next);
3563 	}			/* while (tp1) */
3564 
3565 	if (tot_retrans > 0) {
3566 		/*
3567 		 * Setup the ecn nonce re-sync point. We do this since once
3568 		 * we go to FR something we introduce a Karn's rule scenario
3569 		 * and won't know the totals for the ECN bits.
3570 		 */
3571 		asoc->nonce_resync_tsn = sending_seq;
3572 		asoc->nonce_wait_for_ecne = 0;
3573 		asoc->nonce_sum_check = 0;
3574 	}
3575 }
3576 
3577 struct sctp_tmit_chunk *
3578 sctp_try_advance_peer_ack_point(struct sctp_tcb *stcb,
3579     struct sctp_association *asoc)
3580 {
3581 	struct sctp_tmit_chunk *tp1, *tp2, *a_adv = NULL;
3582 	struct timeval now;
3583 	int now_filled = 0;
3584 
3585 	if (asoc->peer_supports_prsctp == 0) {
3586 		return (NULL);
3587 	}
3588 	tp1 = TAILQ_FIRST(&asoc->sent_queue);
3589 	while (tp1) {
3590 		if (tp1->sent != SCTP_FORWARD_TSN_SKIP &&
3591 		    tp1->sent != SCTP_DATAGRAM_RESEND) {
3592 			/* no chance to advance, out of here */
3593 			break;
3594 		}
3595 		if (!PR_SCTP_ENABLED(tp1->flags)) {
3596 			/*
3597 			 * We can't fwd-tsn past any that are reliable aka
3598 			 * retransmitted until the asoc fails.
3599 			 */
3600 			break;
3601 		}
3602 		if (!now_filled) {
3603 			SCTP_GETTIME_TIMEVAL(&now);
3604 			now_filled = 1;
3605 		}
3606 		tp2 = TAILQ_NEXT(tp1, sctp_next);
3607 		/*
3608 		 * now we got a chunk which is marked for another
3609 		 * retransmission to a PR-stream but has run out its chances
3610 		 * already maybe OR has been marked to skip now. Can we skip
3611 		 * it if its a resend?
3612 		 */
3613 		if (tp1->sent == SCTP_DATAGRAM_RESEND &&
3614 		    (PR_SCTP_TTL_ENABLED(tp1->flags))) {
3615 			/*
3616 			 * Now is this one marked for resend and its time is
3617 			 * now up?
3618 			 */
3619 			if (timevalcmp(&now, &tp1->rec.data.timetodrop, >)) {
3620 				/* Yes so drop it */
3621 				if (tp1->data) {
3622 					sctp_release_pr_sctp_chunk(stcb, tp1,
3623 					    (SCTP_RESPONSE_TO_USER_REQ | SCTP_NOTIFY_DATAGRAM_SENT),
3624 					    &asoc->sent_queue);
3625 				}
3626 			} else {
3627 				/*
3628 				 * No, we are done when hit one for resend
3629 				 * whos time as not expired.
3630 				 */
3631 				break;
3632 			}
3633 		}
3634 		/*
3635 		 * Ok now if this chunk is marked to drop it we can clean up
3636 		 * the chunk, advance our peer ack point and we can check
3637 		 * the next chunk.
3638 		 */
3639 		if (tp1->sent == SCTP_FORWARD_TSN_SKIP) {
3640 			/* advance PeerAckPoint goes forward */
3641 			asoc->advanced_peer_ack_point = tp1->rec.data.TSN_seq;
3642 			a_adv = tp1;
3643 			/*
3644 			 * we don't want to de-queue it here. Just wait for
3645 			 * the next peer SACK to come with a new cumTSN and
3646 			 * then the chunk will be droped in the normal
3647 			 * fashion.
3648 			 */
3649 			if (tp1->data) {
3650 				sctp_free_bufspace(stcb, asoc, tp1, 1);
3651 				/*
3652 				 * Maybe there should be another
3653 				 * notification type
3654 				 */
3655 				sctp_ulp_notify(SCTP_NOTIFY_DG_FAIL, stcb,
3656 				    (SCTP_RESPONSE_TO_USER_REQ | SCTP_NOTIFY_DATAGRAM_SENT),
3657 				    tp1);
3658 				sctp_m_freem(tp1->data);
3659 				tp1->data = NULL;
3660 				if (stcb->sctp_socket) {
3661 					sctp_sowwakeup(stcb->sctp_ep,
3662 					    stcb->sctp_socket);
3663 #ifdef SCTP_WAKE_LOGGING
3664 					sctp_wakeup_log(stcb, tp1->rec.data.TSN_seq, 1, SCTP_WAKESND_FROM_FWDTSN);
3665 #endif
3666 				}
3667 			}
3668 		} else {
3669 			/*
3670 			 * If it is still in RESEND we can advance no
3671 			 * further
3672 			 */
3673 			break;
3674 		}
3675 		/*
3676 		 * If we hit here we just dumped tp1, move to next tsn on
3677 		 * sent queue.
3678 		 */
3679 		tp1 = tp2;
3680 	}
3681 	return (a_adv);
3682 }
3683 
3684 #ifdef SCTP_HIGH_SPEED
3685 struct sctp_hs_raise_drop {
3686 	int32_t cwnd;
3687 	int32_t increase;
3688 	int32_t drop_percent;
3689 };
3690 
3691 #define SCTP_HS_TABLE_SIZE 73
3692 
3693 struct sctp_hs_raise_drop sctp_cwnd_adjust[SCTP_HS_TABLE_SIZE] = {
3694 	{38, 1, 50},		/* 0   */
3695 	{118, 2, 44},		/* 1   */
3696 	{221, 3, 41},		/* 2   */
3697 	{347, 4, 38},		/* 3   */
3698 	{495, 5, 37},		/* 4   */
3699 	{663, 6, 35},		/* 5   */
3700 	{851, 7, 34},		/* 6   */
3701 	{1058, 8, 33},		/* 7   */
3702 	{1284, 9, 32},		/* 8   */
3703 	{1529, 10, 31},		/* 9   */
3704 	{1793, 11, 30},		/* 10  */
3705 	{2076, 12, 29},		/* 11  */
3706 	{2378, 13, 28},		/* 12  */
3707 	{2699, 14, 28},		/* 13  */
3708 	{3039, 15, 27},		/* 14  */
3709 	{3399, 16, 27},		/* 15  */
3710 	{3778, 17, 26},		/* 16  */
3711 	{4177, 18, 26},		/* 17  */
3712 	{4596, 19, 25},		/* 18  */
3713 	{5036, 20, 25},		/* 19  */
3714 	{5497, 21, 24},		/* 20  */
3715 	{5979, 22, 24},		/* 21  */
3716 	{6483, 23, 23},		/* 22  */
3717 	{7009, 24, 23},		/* 23  */
3718 	{7558, 25, 22},		/* 24  */
3719 	{8130, 26, 22},		/* 25  */
3720 	{8726, 27, 22},		/* 26  */
3721 	{9346, 28, 21},		/* 27  */
3722 	{9991, 29, 21},		/* 28  */
3723 	{10661, 30, 21},	/* 29  */
3724 	{11358, 31, 20},	/* 30  */
3725 	{12082, 32, 20},	/* 31  */
3726 	{12834, 33, 20},	/* 32  */
3727 	{13614, 34, 19},	/* 33  */
3728 	{14424, 35, 19},	/* 34  */
3729 	{15265, 36, 19},	/* 35  */
3730 	{16137, 37, 19},	/* 36  */
3731 	{17042, 38, 18},	/* 37  */
3732 	{17981, 39, 18},	/* 38  */
3733 	{18955, 40, 18},	/* 39  */
3734 	{19965, 41, 17},	/* 40  */
3735 	{21013, 42, 17},	/* 41  */
3736 	{22101, 43, 17},	/* 42  */
3737 	{23230, 44, 17},	/* 43  */
3738 	{24402, 45, 16},	/* 44  */
3739 	{25618, 46, 16},	/* 45  */
3740 	{26881, 47, 16},	/* 46  */
3741 	{28193, 48, 16},	/* 47  */
3742 	{29557, 49, 15},	/* 48  */
3743 	{30975, 50, 15},	/* 49  */
3744 	{32450, 51, 15},	/* 50  */
3745 	{33986, 52, 15},	/* 51  */
3746 	{35586, 53, 14},	/* 52  */
3747 	{37253, 54, 14},	/* 53  */
3748 	{38992, 55, 14},	/* 54  */
3749 	{40808, 56, 14},	/* 55  */
3750 	{42707, 57, 13},	/* 56  */
3751 	{44694, 58, 13},	/* 57  */
3752 	{46776, 59, 13},	/* 58  */
3753 	{48961, 60, 13},	/* 59  */
3754 	{51258, 61, 13},	/* 60  */
3755 	{53677, 62, 12},	/* 61  */
3756 	{56230, 63, 12},	/* 62  */
3757 	{58932, 64, 12},	/* 63  */
3758 	{61799, 65, 12},	/* 64  */
3759 	{64851, 66, 11},	/* 65  */
3760 	{68113, 67, 11},	/* 66  */
3761 	{71617, 68, 11},	/* 67  */
3762 	{75401, 69, 10},	/* 68  */
3763 	{79517, 70, 10},	/* 69  */
3764 	{84035, 71, 10},	/* 70  */
3765 	{89053, 72, 10},	/* 71  */
3766 	{94717, 73, 9}		/* 72  */
3767 };
3768 
3769 static void
3770 sctp_hs_cwnd_increase(struct sctp_tcb *stcb, struct sctp_nets *net)
3771 {
3772 	int cur_val, i, indx, incr;
3773 
3774 	cur_val = net->cwnd >> 10;
3775 	indx = SCTP_HS_TABLE_SIZE - 1;
3776 
3777 	if (cur_val < sctp_cwnd_adjust[0].cwnd) {
3778 		/* normal mode */
3779 		if (net->net_ack > net->mtu) {
3780 			net->cwnd += net->mtu;
3781 #ifdef SCTP_CWND_MONITOR
3782 			sctp_log_cwnd(stcb, net, net->mtu, SCTP_CWND_LOG_FROM_SS);
3783 #endif
3784 		} else {
3785 			net->cwnd += net->net_ack;
3786 #ifdef SCTP_CWND_MONITOR
3787 			sctp_log_cwnd(stcb, net, net->net_ack, SCTP_CWND_LOG_FROM_SS);
3788 #endif
3789 		}
3790 	} else {
3791 		for (i = net->last_hs_used; i < SCTP_HS_TABLE_SIZE; i++) {
3792 			if (cur_val < sctp_cwnd_adjust[i].cwnd) {
3793 				indx = i;
3794 				break;
3795 			}
3796 		}
3797 		net->last_hs_used = indx;
3798 		incr = ((sctp_cwnd_adjust[indx].increase) << 10);
3799 		net->cwnd += incr;
3800 #ifdef SCTP_CWND_MONITOR
3801 		sctp_log_cwnd(stcb, net, incr, SCTP_CWND_LOG_FROM_SS);
3802 #endif
3803 	}
3804 }
3805 
3806 static void
3807 sctp_hs_cwnd_decrease(struct sctp_tcb *stcb, struct sctp_nets *net)
3808 {
3809 	int cur_val, i, indx;
3810 
3811 #ifdef SCTP_CWND_MONITOR
3812 	int old_cwnd = net->cwnd;
3813 
3814 #endif
3815 
3816 	cur_val = net->cwnd >> 10;
3817 	indx = net->last_hs_used;
3818 	if (cur_val < sctp_cwnd_adjust[0].cwnd) {
3819 		/* normal mode */
3820 		net->ssthresh = net->cwnd / 2;
3821 		if (net->ssthresh < (net->mtu * 2)) {
3822 			net->ssthresh = 2 * net->mtu;
3823 		}
3824 		net->cwnd = net->ssthresh;
3825 	} else {
3826 		/* drop by the proper amount */
3827 		net->ssthresh = net->cwnd - (int)((net->cwnd / 100) *
3828 		    sctp_cwnd_adjust[net->last_hs_used].drop_percent);
3829 		net->cwnd = net->ssthresh;
3830 		/* now where are we */
3831 		indx = net->last_hs_used;
3832 		cur_val = net->cwnd >> 10;
3833 		/* reset where we are in the table */
3834 		if (cur_val < sctp_cwnd_adjust[0].cwnd) {
3835 			/* feel out of hs */
3836 			net->last_hs_used = 0;
3837 		} else {
3838 			for (i = indx; i >= 1; i--) {
3839 				if (cur_val > sctp_cwnd_adjust[i - 1].cwnd) {
3840 					break;
3841 				}
3842 			}
3843 			net->last_hs_used = indx;
3844 		}
3845 	}
3846 #ifdef SCTP_CWND_MONITOR
3847 	sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_FR);
3848 #endif
3849 
3850 }
3851 
3852 #endif
3853 
3854 extern int sctp_early_fr;
3855 extern int sctp_L2_abc_variable;
3856 
3857 
3858 static __inline void
3859 sctp_cwnd_update(struct sctp_tcb *stcb,
3860     struct sctp_association *asoc,
3861     int accum_moved, int reneged_all, int will_exit)
3862 {
3863 	struct sctp_nets *net;
3864 
3865 	/******************************/
3866 	/* update cwnd and Early FR   */
3867 	/******************************/
3868 	TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
3869 #ifdef JANA_CODE_WHY_THIS
3870 		/*
3871 		 * CMT fast recovery code. Need to debug.
3872 		 */
3873 		if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) {
3874 			if (compare_with_wrap(asoc->last_acked_seq,
3875 			    net->fast_recovery_tsn, MAX_TSN) ||
3876 			    (asoc->last_acked_seq == net->fast_recovery_tsn) ||
3877 			    compare_with_wrap(net->pseudo_cumack, net->fast_recovery_tsn, MAX_TSN) ||
3878 			    (net->pseudo_cumack == net->fast_recovery_tsn)) {
3879 				net->will_exit_fast_recovery = 1;
3880 			}
3881 		}
3882 #endif
3883 		if (sctp_early_fr) {
3884 			/*
3885 			 * So, first of all do we need to have a Early FR
3886 			 * timer running?
3887 			 */
3888 			if (((TAILQ_FIRST(&asoc->sent_queue)) &&
3889 			    (net->ref_count > 1) &&
3890 			    (net->flight_size < net->cwnd)) ||
3891 			    (reneged_all)) {
3892 				/*
3893 				 * yes, so in this case stop it if its
3894 				 * running, and then restart it. Reneging
3895 				 * all is a special case where we want to
3896 				 * run the Early FR timer and then force the
3897 				 * last few unacked to be sent, causing us
3898 				 * to illicit a sack with gaps to force out
3899 				 * the others.
3900 				 */
3901 				if (callout_pending(&net->fr_timer.timer)) {
3902 					SCTP_STAT_INCR(sctps_earlyfrstpidsck2);
3903 					sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
3904 					    SCTP_FROM_SCTP_INDATA + SCTP_LOC_20);
3905 				}
3906 				SCTP_STAT_INCR(sctps_earlyfrstrid);
3907 				sctp_timer_start(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net);
3908 			} else {
3909 				/* No, stop it if its running */
3910 				if (callout_pending(&net->fr_timer.timer)) {
3911 					SCTP_STAT_INCR(sctps_earlyfrstpidsck3);
3912 					sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
3913 					    SCTP_FROM_SCTP_INDATA + SCTP_LOC_21);
3914 				}
3915 			}
3916 		}
3917 		/* if nothing was acked on this destination skip it */
3918 		if (net->net_ack == 0) {
3919 #ifdef SCTP_CWND_LOGGING
3920 			sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK);
3921 #endif
3922 			continue;
3923 		}
3924 		if (net->net_ack2 > 0) {
3925 			/*
3926 			 * Karn's rule applies to clearing error count, this
3927 			 * is optional.
3928 			 */
3929 			net->error_count = 0;
3930 			if ((net->dest_state & SCTP_ADDR_NOT_REACHABLE) ==
3931 			    SCTP_ADDR_NOT_REACHABLE) {
3932 				/* addr came good */
3933 				net->dest_state &= ~SCTP_ADDR_NOT_REACHABLE;
3934 				net->dest_state |= SCTP_ADDR_REACHABLE;
3935 				sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_UP, stcb,
3936 				    SCTP_RECEIVED_SACK, (void *)net);
3937 				/* now was it the primary? if so restore */
3938 				if (net->dest_state & SCTP_ADDR_WAS_PRIMARY) {
3939 					sctp_set_primary_addr(stcb, (struct sockaddr *)NULL, net);
3940 				}
3941 			}
3942 		}
3943 #ifdef JANA_CODE_WHY_THIS
3944 		/*
3945 		 * Cannot skip for CMT. Need to come back and check these
3946 		 * variables for CMT. CMT fast recovery code. Need to debug.
3947 		 */
3948 		if (sctp_cmt_on_off == 1 &&
3949 		    net->fast_retran_loss_recovery &&
3950 		    net->will_exit_fast_recovery == 0)
3951 #endif
3952 			if (sctp_cmt_on_off == 0 && asoc->fast_retran_loss_recovery && will_exit == 0) {
3953 				/*
3954 				 * If we are in loss recovery we skip any
3955 				 * cwnd update
3956 				 */
3957 				goto skip_cwnd_update;
3958 			}
3959 		/*
3960 		 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has
3961 		 * moved.
3962 		 */
3963 		if (accum_moved || (sctp_cmt_on_off && net->new_pseudo_cumack)) {
3964 			/* If the cumulative ack moved we can proceed */
3965 			if (net->cwnd <= net->ssthresh) {
3966 				/* We are in slow start */
3967 				if (net->flight_size + net->net_ack >=
3968 				    net->cwnd) {
3969 #ifdef SCTP_HIGH_SPEED
3970 					sctp_hs_cwnd_increase(stcb, net);
3971 #else
3972 					if (net->net_ack > (net->mtu * sctp_L2_abc_variable)) {
3973 						net->cwnd += (net->mtu * sctp_L2_abc_variable);
3974 #ifdef SCTP_CWND_MONITOR
3975 						sctp_log_cwnd(stcb, net, net->mtu,
3976 						    SCTP_CWND_LOG_FROM_SS);
3977 #endif
3978 
3979 					} else {
3980 						net->cwnd += net->net_ack;
3981 #ifdef SCTP_CWND_MONITOR
3982 						sctp_log_cwnd(stcb, net, net->net_ack,
3983 						    SCTP_CWND_LOG_FROM_SS);
3984 #endif
3985 
3986 					}
3987 #endif
3988 				} else {
3989 					unsigned int dif;
3990 
3991 					dif = net->cwnd - (net->flight_size +
3992 					    net->net_ack);
3993 #ifdef SCTP_CWND_LOGGING
3994 					sctp_log_cwnd(stcb, net, net->net_ack,
3995 					    SCTP_CWND_LOG_NOADV_SS);
3996 #endif
3997 				}
3998 			} else {
3999 				/* We are in congestion avoidance */
4000 				if (net->flight_size + net->net_ack >=
4001 				    net->cwnd) {
4002 					/*
4003 					 * add to pba only if we had a
4004 					 * cwnd's worth (or so) in flight OR
4005 					 * the burst limit was applied.
4006 					 */
4007 					net->partial_bytes_acked +=
4008 					    net->net_ack;
4009 
4010 					/*
4011 					 * Do we need to increase (if pba is
4012 					 * > cwnd)?
4013 					 */
4014 					if (net->partial_bytes_acked >=
4015 					    net->cwnd) {
4016 						if (net->cwnd <
4017 						    net->partial_bytes_acked) {
4018 							net->partial_bytes_acked -=
4019 							    net->cwnd;
4020 						} else {
4021 							net->partial_bytes_acked =
4022 							    0;
4023 						}
4024 						net->cwnd += net->mtu;
4025 #ifdef SCTP_CWND_MONITOR
4026 						sctp_log_cwnd(stcb, net, net->mtu,
4027 						    SCTP_CWND_LOG_FROM_CA);
4028 #endif
4029 					}
4030 #ifdef SCTP_CWND_LOGGING
4031 					else {
4032 						sctp_log_cwnd(stcb, net, net->net_ack,
4033 						    SCTP_CWND_LOG_NOADV_CA);
4034 					}
4035 #endif
4036 				} else {
4037 					unsigned int dif;
4038 
4039 #ifdef SCTP_CWND_LOGGING
4040 					sctp_log_cwnd(stcb, net, net->net_ack,
4041 					    SCTP_CWND_LOG_NOADV_CA);
4042 #endif
4043 					dif = net->cwnd - (net->flight_size +
4044 					    net->net_ack);
4045 				}
4046 			}
4047 		} else {
4048 #ifdef SCTP_CWND_LOGGING
4049 			sctp_log_cwnd(stcb, net, net->mtu,
4050 			    SCTP_CWND_LOG_NO_CUMACK);
4051 #endif
4052 		}
4053 skip_cwnd_update:
4054 		/*
4055 		 * NOW, according to Karn's rule do we need to restore the
4056 		 * RTO timer back? Check our net_ack2. If not set then we
4057 		 * have a ambiguity.. i.e. all data ack'd was sent to more
4058 		 * than one place.
4059 		 */
4060 		if (net->net_ack2) {
4061 			/* restore any doubled timers */
4062 			net->RTO = ((net->lastsa >> 2) + net->lastsv) >> 1;
4063 			if (net->RTO < stcb->asoc.minrto) {
4064 				net->RTO = stcb->asoc.minrto;
4065 			}
4066 			if (net->RTO > stcb->asoc.maxrto) {
4067 				net->RTO = stcb->asoc.maxrto;
4068 			}
4069 		}
4070 	}
4071 }
4072 
4073 
4074 void
4075 sctp_express_handle_sack(struct sctp_tcb *stcb, uint32_t cumack,
4076     uint32_t rwnd, int nonce_sum_flag, int *abort_now)
4077 {
4078 	struct sctp_nets *net;
4079 	struct sctp_association *asoc;
4080 	struct sctp_tmit_chunk *tp1, *tp2;
4081 	int j;
4082 
4083 	SCTP_TCB_LOCK_ASSERT(stcb);
4084 	asoc = &stcb->asoc;
4085 	/* First setup for CC stuff */
4086 	TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
4087 		net->prev_cwnd = net->cwnd;
4088 		net->net_ack = 0;
4089 		net->net_ack2 = 0;
4090 	}
4091 	asoc->this_sack_highest_gap = cumack;
4092 	stcb->asoc.overall_error_count = 0;
4093 	/* process the new consecutive TSN first */
4094 	tp1 = TAILQ_FIRST(&asoc->sent_queue);
4095 	while (tp1) {
4096 		tp2 = TAILQ_NEXT(tp1, sctp_next);
4097 		if (compare_with_wrap(cumack, tp1->rec.data.TSN_seq,
4098 		    MAX_TSN) ||
4099 		    cumack == tp1->rec.data.TSN_seq) {
4100 			if (tp1->sent != SCTP_DATAGRAM_UNSENT) {
4101 				/*
4102 				 * ECN Nonce: Add the nonce to the sender's
4103 				 * nonce sum
4104 				 */
4105 				asoc->nonce_sum_expect_base += tp1->rec.data.ect_nonce;
4106 				if (tp1->sent < SCTP_DATAGRAM_ACKED) {
4107 					/*
4108 					 * If it is less than ACKED, it is
4109 					 * now no-longer in flight. Higher
4110 					 * values may occur during marking
4111 					 */
4112 #ifdef SCTP_FLIGHT_LOGGING
4113 					sctp_misc_ints(SCTP_FLIGHT_LOG_DOWN,
4114 					    tp1->whoTo->flight_size,
4115 					    tp1->book_size,
4116 					    (uintptr_t) stcb,
4117 					    tp1->rec.data.TSN_seq);
4118 #endif
4119 
4120 					if (tp1->whoTo->flight_size >= tp1->book_size) {
4121 						tp1->whoTo->flight_size -= tp1->book_size;
4122 					} else {
4123 						tp1->whoTo->flight_size = 0;
4124 					}
4125 					if (asoc->total_flight >= tp1->book_size) {
4126 						asoc->total_flight -= tp1->book_size;
4127 						if (asoc->total_flight_count > 0)
4128 							asoc->total_flight_count--;
4129 					} else {
4130 						asoc->total_flight = 0;
4131 						asoc->total_flight_count = 0;
4132 					}
4133 					tp1->whoTo->net_ack += tp1->send_size;
4134 					if (tp1->snd_count < 2) {
4135 						/*
4136 						 * True non-retransmited
4137 						 * chunk
4138 						 */
4139 						tp1->whoTo->net_ack2 +=
4140 						    tp1->send_size;
4141 
4142 						/* update RTO too? */
4143 						if ((tp1->do_rtt) && (tp1->whoTo->rto_pending)) {
4144 							tp1->whoTo->RTO =
4145 							    sctp_calculate_rto(stcb,
4146 							    asoc, tp1->whoTo,
4147 							    &tp1->sent_rcv_time);
4148 							tp1->whoTo->rto_pending = 0;
4149 							tp1->do_rtt = 0;
4150 						}
4151 					}
4152 #ifdef SCTP_CWND_LOGGING
4153 					sctp_log_cwnd(stcb, tp1->whoTo, tp1->rec.data.TSN_seq, SCTP_CWND_LOG_FROM_SACK);
4154 #endif
4155 				}
4156 				if (tp1->sent == SCTP_DATAGRAM_RESEND) {
4157 					sctp_ucount_decr(asoc->sent_queue_retran_cnt);
4158 				}
4159 				tp1->sent = SCTP_DATAGRAM_ACKED;
4160 			}
4161 		} else {
4162 			break;
4163 		}
4164 		TAILQ_REMOVE(&asoc->sent_queue, tp1, sctp_next);
4165 		if (tp1->data) {
4166 			sctp_free_bufspace(stcb, asoc, tp1, 1);
4167 			sctp_m_freem(tp1->data);
4168 		}
4169 #ifdef SCTP_SACK_LOGGING
4170 		sctp_log_sack(asoc->last_acked_seq,
4171 		    cumack,
4172 		    tp1->rec.data.TSN_seq,
4173 		    0,
4174 		    0,
4175 		    SCTP_LOG_FREE_SENT);
4176 #endif
4177 		tp1->data = NULL;
4178 		asoc->sent_queue_cnt--;
4179 		sctp_free_remote_addr(tp1->whoTo);
4180 		sctp_free_a_chunk(stcb, tp1);
4181 		tp1 = tp2;
4182 	}
4183 	if (stcb->sctp_socket) {
4184 		SOCKBUF_LOCK(&stcb->sctp_socket->so_snd);
4185 #ifdef SCTP_WAKE_LOGGING
4186 		sctp_wakeup_log(stcb, cumack, 1, SCTP_WAKESND_FROM_SACK);
4187 #endif
4188 		sctp_sowwakeup_locked(stcb->sctp_ep, stcb->sctp_socket);
4189 #ifdef SCTP_WAKE_LOGGING
4190 	} else {
4191 		sctp_wakeup_log(stcb, cumack, 1, SCTP_NOWAKE_FROM_SACK);
4192 #endif
4193 	}
4194 
4195 	if (asoc->last_acked_seq != cumack)
4196 		sctp_cwnd_update(stcb, asoc, 1, 0, 0);
4197 	asoc->last_acked_seq = cumack;
4198 	if (TAILQ_EMPTY(&asoc->sent_queue)) {
4199 		/* nothing left in-flight */
4200 		TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
4201 			net->flight_size = 0;
4202 			net->partial_bytes_acked = 0;
4203 		}
4204 		asoc->total_flight = 0;
4205 		asoc->total_flight_count = 0;
4206 	}
4207 	/* Fix up the a-p-a-p for future PR-SCTP sends */
4208 	if (compare_with_wrap(cumack, asoc->advanced_peer_ack_point, MAX_TSN)) {
4209 		asoc->advanced_peer_ack_point = cumack;
4210 	}
4211 	/* ECN Nonce updates */
4212 	if (asoc->ecn_nonce_allowed) {
4213 		if (asoc->nonce_sum_check) {
4214 			if (nonce_sum_flag != ((asoc->nonce_sum_expect_base) & SCTP_SACK_NONCE_SUM)) {
4215 				if (asoc->nonce_wait_for_ecne == 0) {
4216 					struct sctp_tmit_chunk *lchk;
4217 
4218 					lchk = TAILQ_FIRST(&asoc->send_queue);
4219 					asoc->nonce_wait_for_ecne = 1;
4220 					if (lchk) {
4221 						asoc->nonce_wait_tsn = lchk->rec.data.TSN_seq;
4222 					} else {
4223 						asoc->nonce_wait_tsn = asoc->sending_seq;
4224 					}
4225 				} else {
4226 					if (compare_with_wrap(asoc->last_acked_seq, asoc->nonce_wait_tsn, MAX_TSN) ||
4227 					    (asoc->last_acked_seq == asoc->nonce_wait_tsn)) {
4228 						/*
4229 						 * Misbehaving peer. We need
4230 						 * to react to this guy
4231 						 */
4232 						asoc->ecn_allowed = 0;
4233 						asoc->ecn_nonce_allowed = 0;
4234 					}
4235 				}
4236 			}
4237 		} else {
4238 			/* See if Resynchronization Possible */
4239 			if (compare_with_wrap(asoc->last_acked_seq, asoc->nonce_resync_tsn, MAX_TSN)) {
4240 				asoc->nonce_sum_check = 1;
4241 				/*
4242 				 * now we must calculate what the base is.
4243 				 * We do this based on two things, we know
4244 				 * the total's for all the segments
4245 				 * gap-acked in the SACK (none), We also
4246 				 * know the SACK's nonce sum, its in
4247 				 * nonce_sum_flag. So we can build a truth
4248 				 * table to back-calculate the new value of
4249 				 * asoc->nonce_sum_expect_base:
4250 				 *
4251 				 * SACK-flag-Value         Seg-Sums Base 0 0 0
4252 				 * 1                    0 1 0 1 1 1
4253 				 * 1 0
4254 				 */
4255 				asoc->nonce_sum_expect_base = (0 ^ nonce_sum_flag) & SCTP_SACK_NONCE_SUM;
4256 			}
4257 		}
4258 	}
4259 	/* RWND update */
4260 	asoc->peers_rwnd = sctp_sbspace_sub(rwnd,
4261 	    (uint32_t) (asoc->total_flight + (asoc->sent_queue_cnt * sctp_peer_chunk_oh)));
4262 	if (asoc->peers_rwnd < stcb->sctp_ep->sctp_ep.sctp_sws_sender) {
4263 		/* SWS sender side engages */
4264 		asoc->peers_rwnd = 0;
4265 	}
4266 	/* Now assure a timer where data is queued at */
4267 again:
4268 	j = 0;
4269 	TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
4270 		if (net->flight_size) {
4271 			int to_ticks;
4272 
4273 			if (net->RTO == 0) {
4274 				to_ticks = MSEC_TO_TICKS(stcb->asoc.initial_rto);
4275 			} else {
4276 				to_ticks = MSEC_TO_TICKS(net->RTO);
4277 			}
4278 			j++;
4279 			callout_reset(&net->rxt_timer.timer, to_ticks,
4280 			    sctp_timeout_handler, &net->rxt_timer);
4281 		} else {
4282 			if (callout_pending(&net->rxt_timer.timer)) {
4283 				sctp_timer_stop(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
4284 				    stcb, net,
4285 				    SCTP_FROM_SCTP_INDATA + SCTP_LOC_22);
4286 			}
4287 			if (sctp_early_fr) {
4288 				if (callout_pending(&net->fr_timer.timer)) {
4289 					SCTP_STAT_INCR(sctps_earlyfrstpidsck4);
4290 					sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
4291 					    SCTP_FROM_SCTP_INDATA + SCTP_LOC_23);
4292 				}
4293 			}
4294 		}
4295 	}
4296 	if ((j == 0) && (!TAILQ_EMPTY(&asoc->sent_queue)) && (asoc->sent_queue_retran_cnt == 0)) {
4297 		/* huh, this should not happen */
4298 #ifdef INVARIANTS
4299 		panic("Flight size incorrect? fixing??");
4300 #else
4301 		printf("Flight size incorrect?  fixing\n");
4302 		TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
4303 			net->flight_size = 0;
4304 		}
4305 		asoc->total_flight = 0;
4306 		asoc->total_flight_count = 0;
4307 		asoc->sent_queue_retran_cnt = 0;
4308 		TAILQ_FOREACH(tp1, &asoc->sent_queue, sctp_next) {
4309 			if (tp1->sent < SCTP_DATAGRAM_RESEND) {
4310 				tp1->whoTo->flight_size += tp1->book_size;
4311 				asoc->total_flight += tp1->book_size;
4312 				asoc->total_flight_count++;
4313 			} else if (tp1->sent == SCTP_DATAGRAM_RESEND) {
4314 				asoc->sent_queue_retran_cnt++;
4315 			}
4316 		}
4317 #endif
4318 		goto again;
4319 	}
4320 	/**********************************/
4321 	/* Now what about shutdown issues */
4322 	/**********************************/
4323 	if (TAILQ_EMPTY(&asoc->send_queue) && TAILQ_EMPTY(&asoc->sent_queue)) {
4324 		/* nothing left on sendqueue.. consider done */
4325 		/* clean up */
4326 		if ((asoc->stream_queue_cnt == 1) &&
4327 		    ((asoc->state & SCTP_STATE_SHUTDOWN_PENDING) ||
4328 		    (asoc->state & SCTP_STATE_SHUTDOWN_RECEIVED)) &&
4329 		    (asoc->locked_on_sending)
4330 		    ) {
4331 			struct sctp_stream_queue_pending *sp;
4332 
4333 			/*
4334 			 * I may be in a state where we got all across.. but
4335 			 * cannot write more due to a shutdown... we abort
4336 			 * since the user did not indicate EOR in this case.
4337 			 * The sp will be cleaned during free of the asoc.
4338 			 */
4339 			sp = TAILQ_LAST(&((asoc->locked_on_sending)->outqueue),
4340 			    sctp_streamhead);
4341 			if ((sp) && (sp->length == 0) && (sp->msg_is_complete == 0)) {
4342 				asoc->state |= SCTP_STATE_PARTIAL_MSG_LEFT;
4343 				asoc->locked_on_sending = NULL;
4344 				asoc->stream_queue_cnt--;
4345 			}
4346 		}
4347 		if ((asoc->state & SCTP_STATE_SHUTDOWN_PENDING) &&
4348 		    (asoc->stream_queue_cnt == 0)) {
4349 			if (asoc->state & SCTP_STATE_PARTIAL_MSG_LEFT) {
4350 				/* Need to abort here */
4351 				struct mbuf *oper;
4352 
4353 		abort_out_now:
4354 				*abort_now = 1;
4355 				/* XXX */
4356 				oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
4357 				    0, M_DONTWAIT, 1, MT_DATA);
4358 				if (oper) {
4359 					struct sctp_paramhdr *ph;
4360 					uint32_t *ippp;
4361 
4362 					oper->m_len = sizeof(struct sctp_paramhdr) +
4363 					    sizeof(uint32_t);
4364 					ph = mtod(oper, struct sctp_paramhdr *);
4365 					ph->param_type = htons(SCTP_CAUSE_USER_INITIATED_ABT);
4366 					ph->param_length = htons(oper->m_len);
4367 					ippp = (uint32_t *) (ph + 1);
4368 					*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_24);
4369 				}
4370 				stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_24;
4371 				sctp_abort_an_association(stcb->sctp_ep, stcb, SCTP_RESPONSE_TO_USER_REQ, oper);
4372 			} else {
4373 				asoc->state = SCTP_STATE_SHUTDOWN_SENT;
4374 				SCTP_STAT_DECR_GAUGE32(sctps_currestab);
4375 				sctp_stop_timers_for_shutdown(stcb);
4376 				sctp_send_shutdown(stcb,
4377 				    stcb->asoc.primary_destination);
4378 				sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWN,
4379 				    stcb->sctp_ep, stcb, asoc->primary_destination);
4380 				sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
4381 				    stcb->sctp_ep, stcb, asoc->primary_destination);
4382 			}
4383 		} else if ((SCTP_GET_STATE(asoc) == SCTP_STATE_SHUTDOWN_RECEIVED) &&
4384 		    (asoc->stream_queue_cnt == 0)) {
4385 			if (asoc->state & SCTP_STATE_PARTIAL_MSG_LEFT) {
4386 				goto abort_out_now;
4387 			}
4388 			asoc->state = SCTP_STATE_SHUTDOWN_ACK_SENT;
4389 			SCTP_STAT_DECR_GAUGE32(sctps_currestab);
4390 			sctp_send_shutdown_ack(stcb,
4391 			    stcb->asoc.primary_destination);
4392 
4393 			sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNACK,
4394 			    stcb->sctp_ep, stcb, asoc->primary_destination);
4395 		}
4396 	}
4397 #ifdef SCTP_SACK_RWND_LOGGING
4398 	sctp_misc_ints(SCTP_SACK_RWND_UPDATE,
4399 	    rwnd,
4400 	    stcb->asoc.peers_rwnd,
4401 	    stcb->asoc.total_flight,
4402 	    stcb->asoc.total_output_queue_size);
4403 
4404 #endif
4405 }
4406 
4407 
4408 
4409 void
4410 sctp_handle_sack(struct sctp_sack_chunk *ch, struct sctp_tcb *stcb,
4411     struct sctp_nets *net_from, int *abort_now)
4412 {
4413 	struct sctp_association *asoc;
4414 	struct sctp_sack *sack;
4415 	struct sctp_tmit_chunk *tp1, *tp2;
4416 	uint32_t cum_ack, last_tsn, biggest_tsn_acked, biggest_tsn_newly_acked,
4417 	         this_sack_lowest_newack;
4418 	uint16_t num_seg, num_dup;
4419 	uint16_t wake_him = 0;
4420 	unsigned int sack_length;
4421 	uint32_t send_s;
4422 	long j;
4423 	int accum_moved = 0;
4424 	int will_exit_fast_recovery = 0;
4425 	uint32_t a_rwnd;
4426 	struct sctp_nets *net = NULL;
4427 	int nonce_sum_flag, ecn_seg_sums = 0;
4428 	uint8_t reneged_all = 0;
4429 	uint8_t cmt_dac_flag;
4430 
4431 	/*
4432 	 * we take any chance we can to service our queues since we cannot
4433 	 * get awoken when the socket is read from :<
4434 	 */
4435 	/*
4436 	 * Now perform the actual SACK handling: 1) Verify that it is not an
4437 	 * old sack, if so discard. 2) If there is nothing left in the send
4438 	 * queue (cum-ack is equal to last acked) then you have a duplicate
4439 	 * too, update any rwnd change and verify no timers are running.
4440 	 * then return. 3) Process any new consequtive data i.e. cum-ack
4441 	 * moved process these first and note that it moved. 4) Process any
4442 	 * sack blocks. 5) Drop any acked from the queue. 6) Check for any
4443 	 * revoked blocks and mark. 7) Update the cwnd. 8) Nothing left,
4444 	 * sync up flightsizes and things, stop all timers and also check
4445 	 * for shutdown_pending state. If so then go ahead and send off the
4446 	 * shutdown. If in shutdown recv, send off the shutdown-ack and
4447 	 * start that timer, Ret. 9) Strike any non-acked things and do FR
4448 	 * procedure if needed being sure to set the FR flag. 10) Do pr-sctp
4449 	 * procedures. 11) Apply any FR penalties. 12) Assure we will SACK
4450 	 * if in shutdown_recv state.
4451 	 */
4452 	SCTP_TCB_LOCK_ASSERT(stcb);
4453 	sack = &ch->sack;
4454 	/* CMT DAC algo */
4455 	this_sack_lowest_newack = 0;
4456 	j = 0;
4457 	sack_length = ntohs(ch->ch.chunk_length);
4458 	if (sack_length < sizeof(struct sctp_sack_chunk)) {
4459 #ifdef SCTP_DEBUG
4460 		if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
4461 			printf("Bad size on sack chunk .. to small\n");
4462 		}
4463 #endif
4464 		return;
4465 	}
4466 	/* ECN Nonce */
4467 	SCTP_STAT_INCR(sctps_slowpath_sack);
4468 	nonce_sum_flag = ch->ch.chunk_flags & SCTP_SACK_NONCE_SUM;
4469 	cum_ack = last_tsn = ntohl(sack->cum_tsn_ack);
4470 	num_seg = ntohs(sack->num_gap_ack_blks);
4471 	a_rwnd = (uint32_t) ntohl(sack->a_rwnd);
4472 
4473 	/* CMT DAC algo */
4474 	cmt_dac_flag = ch->ch.chunk_flags & SCTP_SACK_CMT_DAC;
4475 	num_dup = ntohs(sack->num_dup_tsns);
4476 
4477 
4478 	stcb->asoc.overall_error_count = 0;
4479 	asoc = &stcb->asoc;
4480 #ifdef SCTP_SACK_LOGGING
4481 	sctp_log_sack(asoc->last_acked_seq,
4482 	    cum_ack,
4483 	    0,
4484 	    num_seg,
4485 	    num_dup,
4486 	    SCTP_LOG_NEW_SACK);
4487 #endif
4488 #if defined(SCTP_FR_LOGGING) || defined(SCTP_EARLYFR_LOGGING)
4489 	if (num_dup) {
4490 		int off_to_dup, iii;
4491 		uint32_t *dupdata;
4492 
4493 		off_to_dup = (num_seg * sizeof(struct sctp_gap_ack_block)) + sizeof(struct sctp_sack_chunk);
4494 		if ((off_to_dup + (num_dup * sizeof(uint32_t))) <= sack_length) {
4495 			dupdata = (uint32_t *) ((caddr_t)ch + off_to_dup);
4496 			for (iii = 0; iii < num_dup; iii++) {
4497 				sctp_log_fr(*dupdata, 0, 0, SCTP_FR_DUPED);
4498 				dupdata++;
4499 
4500 			}
4501 		} else {
4502 			printf("Size invalid offset to dups:%d number dups:%d sack_len:%d num gaps:%d\n",
4503 			    off_to_dup, num_dup, sack_length, num_seg);
4504 		}
4505 	}
4506 #endif
4507 	/* reality check */
4508 	if (TAILQ_EMPTY(&asoc->send_queue)) {
4509 		send_s = asoc->sending_seq;
4510 	} else {
4511 		tp1 = TAILQ_FIRST(&asoc->send_queue);
4512 		send_s = tp1->rec.data.TSN_seq;
4513 	}
4514 
4515 	if (sctp_strict_sacks) {
4516 		if (cum_ack == send_s ||
4517 		    compare_with_wrap(cum_ack, send_s, MAX_TSN)) {
4518 			struct mbuf *oper;
4519 
4520 			/*
4521 			 * no way, we have not even sent this TSN out yet.
4522 			 * Peer is hopelessly messed up with us.
4523 			 */
4524 	hopeless_peer:
4525 			*abort_now = 1;
4526 			/* XXX */
4527 			oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
4528 			    0, M_DONTWAIT, 1, MT_DATA);
4529 			if (oper) {
4530 				struct sctp_paramhdr *ph;
4531 				uint32_t *ippp;
4532 
4533 				oper->m_len = sizeof(struct sctp_paramhdr) +
4534 				    sizeof(uint32_t);
4535 				ph = mtod(oper, struct sctp_paramhdr *);
4536 				ph->param_type = htons(SCTP_CAUSE_PROTOCOL_VIOLATION);
4537 				ph->param_length = htons(oper->m_len);
4538 				ippp = (uint32_t *) (ph + 1);
4539 				*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_25);
4540 			}
4541 			stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_25;
4542 			sctp_abort_an_association(stcb->sctp_ep, stcb, SCTP_PEER_FAULTY, oper);
4543 			return;
4544 		}
4545 	}
4546 	/**********************/
4547 	/* 1) check the range */
4548 	/**********************/
4549 	if (compare_with_wrap(asoc->last_acked_seq, last_tsn, MAX_TSN)) {
4550 		/* acking something behind */
4551 		return;
4552 	}
4553 	/* update the Rwnd of the peer */
4554 	if (TAILQ_EMPTY(&asoc->sent_queue) &&
4555 	    TAILQ_EMPTY(&asoc->send_queue) &&
4556 	    (asoc->stream_queue_cnt == 0)
4557 	    ) {
4558 		/* nothing left on send/sent and strmq */
4559 #ifdef SCTP_LOG_RWND
4560 		sctp_log_rwnd_set(SCTP_SET_PEER_RWND_VIA_SACK,
4561 		    asoc->peers_rwnd, 0, 0, a_rwnd);
4562 #endif
4563 		asoc->peers_rwnd = a_rwnd;
4564 		if (asoc->sent_queue_retran_cnt) {
4565 			asoc->sent_queue_retran_cnt = 0;
4566 		}
4567 		if (asoc->peers_rwnd < stcb->sctp_ep->sctp_ep.sctp_sws_sender) {
4568 			/* SWS sender side engages */
4569 			asoc->peers_rwnd = 0;
4570 		}
4571 		/* stop any timers */
4572 		TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
4573 			sctp_timer_stop(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
4574 			    stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_26);
4575 			if (sctp_early_fr) {
4576 				if (callout_pending(&net->fr_timer.timer)) {
4577 					SCTP_STAT_INCR(sctps_earlyfrstpidsck1);
4578 					sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
4579 					    SCTP_FROM_SCTP_INDATA + SCTP_LOC_26);
4580 				}
4581 			}
4582 			net->partial_bytes_acked = 0;
4583 			net->flight_size = 0;
4584 		}
4585 		asoc->total_flight = 0;
4586 		asoc->total_flight_count = 0;
4587 		return;
4588 	}
4589 	/*
4590 	 * We init netAckSz and netAckSz2 to 0. These are used to track 2
4591 	 * things. The total byte count acked is tracked in netAckSz AND
4592 	 * netAck2 is used to track the total bytes acked that are un-
4593 	 * amibguious and were never retransmitted. We track these on a per
4594 	 * destination address basis.
4595 	 */
4596 	TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
4597 		net->prev_cwnd = net->cwnd;
4598 		net->net_ack = 0;
4599 		net->net_ack2 = 0;
4600 
4601 		/*
4602 		 * CMT: Reset CUC algo variable before SACK processing
4603 		 */
4604 		net->new_pseudo_cumack = 0;
4605 		net->will_exit_fast_recovery = 0;
4606 	}
4607 	/* process the new consecutive TSN first */
4608 	tp1 = TAILQ_FIRST(&asoc->sent_queue);
4609 	while (tp1) {
4610 		if (compare_with_wrap(last_tsn, tp1->rec.data.TSN_seq,
4611 		    MAX_TSN) ||
4612 		    last_tsn == tp1->rec.data.TSN_seq) {
4613 			if (tp1->sent != SCTP_DATAGRAM_UNSENT) {
4614 				/*
4615 				 * ECN Nonce: Add the nonce to the sender's
4616 				 * nonce sum
4617 				 */
4618 				asoc->nonce_sum_expect_base += tp1->rec.data.ect_nonce;
4619 				accum_moved = 1;
4620 				if (tp1->sent < SCTP_DATAGRAM_ACKED) {
4621 					/*
4622 					 * If it is less than ACKED, it is
4623 					 * now no-longer in flight. Higher
4624 					 * values may occur during marking
4625 					 */
4626 					if ((tp1->whoTo->dest_state &
4627 					    SCTP_ADDR_UNCONFIRMED) &&
4628 					    (tp1->snd_count < 2)) {
4629 						/*
4630 						 * If there was no retran
4631 						 * and the address is
4632 						 * un-confirmed and we sent
4633 						 * there and are now
4634 						 * sacked.. its confirmed,
4635 						 * mark it so.
4636 						 */
4637 						tp1->whoTo->dest_state &=
4638 						    ~SCTP_ADDR_UNCONFIRMED;
4639 					}
4640 #ifdef SCTP_FLIGHT_LOGGING
4641 					sctp_misc_ints(SCTP_FLIGHT_LOG_DOWN,
4642 					    tp1->whoTo->flight_size,
4643 					    tp1->book_size,
4644 					    (uintptr_t) stcb,
4645 					    tp1->rec.data.TSN_seq);
4646 #endif
4647 					if (tp1->whoTo->flight_size >= tp1->book_size) {
4648 						tp1->whoTo->flight_size -= tp1->book_size;
4649 					} else {
4650 						tp1->whoTo->flight_size = 0;
4651 					}
4652 					if (asoc->total_flight >= tp1->book_size) {
4653 						asoc->total_flight -= tp1->book_size;
4654 						if (asoc->total_flight_count > 0)
4655 							asoc->total_flight_count--;
4656 					} else {
4657 						asoc->total_flight = 0;
4658 						asoc->total_flight_count = 0;
4659 					}
4660 					tp1->whoTo->net_ack += tp1->send_size;
4661 
4662 					/* CMT SFR and DAC algos */
4663 					this_sack_lowest_newack = tp1->rec.data.TSN_seq;
4664 					tp1->whoTo->saw_newack = 1;
4665 
4666 					if (tp1->snd_count < 2) {
4667 						/*
4668 						 * True non-retransmited
4669 						 * chunk
4670 						 */
4671 						tp1->whoTo->net_ack2 +=
4672 						    tp1->send_size;
4673 
4674 						/* update RTO too? */
4675 						if (tp1->do_rtt) {
4676 							tp1->whoTo->RTO =
4677 							    sctp_calculate_rto(stcb,
4678 							    asoc, tp1->whoTo,
4679 							    &tp1->sent_rcv_time);
4680 							tp1->whoTo->rto_pending = 0;
4681 							tp1->do_rtt = 0;
4682 						}
4683 					}
4684 					/*
4685 					 * CMT: CUCv2 algorithm. From the
4686 					 * cumack'd TSNs, for each TSN being
4687 					 * acked for the first time, set the
4688 					 * following variables for the
4689 					 * corresp destination.
4690 					 * new_pseudo_cumack will trigger a
4691 					 * cwnd update.
4692 					 * find_(rtx_)pseudo_cumack will
4693 					 * trigger search for the next
4694 					 * expected (rtx-)pseudo-cumack.
4695 					 */
4696 					tp1->whoTo->new_pseudo_cumack = 1;
4697 					tp1->whoTo->find_pseudo_cumack = 1;
4698 					tp1->whoTo->find_rtx_pseudo_cumack = 1;
4699 
4700 
4701 #ifdef SCTP_SACK_LOGGING
4702 					sctp_log_sack(asoc->last_acked_seq,
4703 					    cum_ack,
4704 					    tp1->rec.data.TSN_seq,
4705 					    0,
4706 					    0,
4707 					    SCTP_LOG_TSN_ACKED);
4708 #endif
4709 #ifdef SCTP_CWND_LOGGING
4710 					sctp_log_cwnd(stcb, tp1->whoTo, tp1->rec.data.TSN_seq, SCTP_CWND_LOG_FROM_SACK);
4711 #endif
4712 				}
4713 				if (tp1->sent == SCTP_DATAGRAM_RESEND) {
4714 					sctp_ucount_decr(asoc->sent_queue_retran_cnt);
4715 #ifdef SCTP_AUDITING_ENABLED
4716 					sctp_audit_log(0xB3,
4717 					    (asoc->sent_queue_retran_cnt & 0x000000ff));
4718 #endif
4719 				}
4720 				tp1->sent = SCTP_DATAGRAM_ACKED;
4721 			}
4722 		} else {
4723 			break;
4724 		}
4725 		tp1 = TAILQ_NEXT(tp1, sctp_next);
4726 	}
4727 	biggest_tsn_newly_acked = biggest_tsn_acked = last_tsn;
4728 	/* always set this up to cum-ack */
4729 	asoc->this_sack_highest_gap = last_tsn;
4730 
4731 	if (((num_seg * (sizeof(struct sctp_gap_ack_block))) + sizeof(struct sctp_sack_chunk)) > sack_length) {
4732 
4733 		/* skip corrupt segments */
4734 		goto skip_segments;
4735 	}
4736 	if (num_seg > 0) {
4737 
4738 		/*
4739 		 * CMT: SFR algo (and HTNA) - this_sack_highest_newack has
4740 		 * to be greater than the cumack. Also reset saw_newack to 0
4741 		 * for all dests.
4742 		 */
4743 		TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
4744 			net->saw_newack = 0;
4745 			net->this_sack_highest_newack = last_tsn;
4746 		}
4747 
4748 		/*
4749 		 * thisSackHighestGap will increase while handling NEW
4750 		 * segments this_sack_highest_newack will increase while
4751 		 * handling NEWLY ACKED chunks. this_sack_lowest_newack is
4752 		 * used for CMT DAC algo. saw_newack will also change.
4753 		 */
4754 		sctp_handle_segments(stcb, asoc, ch, last_tsn,
4755 		    &biggest_tsn_acked, &biggest_tsn_newly_acked, &this_sack_lowest_newack,
4756 		    num_seg, &ecn_seg_sums);
4757 
4758 		if (sctp_strict_sacks) {
4759 			/*
4760 			 * validate the biggest_tsn_acked in the gap acks if
4761 			 * strict adherence is wanted.
4762 			 */
4763 			if ((biggest_tsn_acked == send_s) ||
4764 			    (compare_with_wrap(biggest_tsn_acked, send_s, MAX_TSN))) {
4765 				/*
4766 				 * peer is either confused or we are under
4767 				 * attack. We must abort.
4768 				 */
4769 				goto hopeless_peer;
4770 			}
4771 		}
4772 	}
4773 skip_segments:
4774 	/*******************************************/
4775 	/* cancel ALL T3-send timer if accum moved */
4776 	/*******************************************/
4777 	if (sctp_cmt_on_off) {
4778 		TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
4779 			if (net->new_pseudo_cumack)
4780 				sctp_timer_stop(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
4781 				    stcb, net,
4782 				    SCTP_FROM_SCTP_INDATA + SCTP_LOC_27);
4783 
4784 		}
4785 	} else {
4786 		if (accum_moved) {
4787 			TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
4788 				sctp_timer_stop(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
4789 				    stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_28);
4790 			}
4791 		}
4792 	}
4793 	/********************************************/
4794 	/* drop the acked chunks from the sendqueue */
4795 	/********************************************/
4796 	asoc->last_acked_seq = cum_ack;
4797 
4798 	tp1 = TAILQ_FIRST(&asoc->sent_queue);
4799 	if (tp1 == NULL)
4800 		goto done_with_it;
4801 	do {
4802 		if (compare_with_wrap(tp1->rec.data.TSN_seq, cum_ack,
4803 		    MAX_TSN)) {
4804 			break;
4805 		}
4806 		if (tp1->sent == SCTP_DATAGRAM_UNSENT) {
4807 			/* no more sent on list */
4808 			break;
4809 		}
4810 		tp2 = TAILQ_NEXT(tp1, sctp_next);
4811 		TAILQ_REMOVE(&asoc->sent_queue, tp1, sctp_next);
4812 		/*
4813 		 * Friendlier printf in lieu of panic now that I think its
4814 		 * fixed
4815 		 */
4816 
4817 		if (tp1->pr_sctp_on) {
4818 			if (asoc->pr_sctp_cnt != 0)
4819 				asoc->pr_sctp_cnt--;
4820 		}
4821 		if ((TAILQ_FIRST(&asoc->sent_queue) == NULL) &&
4822 		    (asoc->total_flight > 0)) {
4823 			printf("Warning flight size incorrect should be 0 is %d\n",
4824 			    asoc->total_flight);
4825 			asoc->total_flight = 0;
4826 		}
4827 		if (tp1->data) {
4828 			sctp_free_bufspace(stcb, asoc, tp1, 1);
4829 			sctp_m_freem(tp1->data);
4830 			if (PR_SCTP_BUF_ENABLED(tp1->flags)) {
4831 				asoc->sent_queue_cnt_removeable--;
4832 			}
4833 		}
4834 #ifdef SCTP_SACK_LOGGING
4835 		sctp_log_sack(asoc->last_acked_seq,
4836 		    cum_ack,
4837 		    tp1->rec.data.TSN_seq,
4838 		    0,
4839 		    0,
4840 		    SCTP_LOG_FREE_SENT);
4841 #endif
4842 		tp1->data = NULL;
4843 		asoc->sent_queue_cnt--;
4844 		sctp_free_remote_addr(tp1->whoTo);
4845 
4846 		sctp_free_a_chunk(stcb, tp1);
4847 		wake_him++;
4848 		tp1 = tp2;
4849 	} while (tp1 != NULL);
4850 
4851 done_with_it:
4852 	if ((wake_him) && (stcb->sctp_socket)) {
4853 		SOCKBUF_LOCK(&stcb->sctp_socket->so_snd);
4854 #ifdef SCTP_WAKE_LOGGING
4855 		sctp_wakeup_log(stcb, cum_ack, wake_him, SCTP_WAKESND_FROM_SACK);
4856 #endif
4857 		sctp_sowwakeup_locked(stcb->sctp_ep, stcb->sctp_socket);
4858 #ifdef SCTP_WAKE_LOGGING
4859 	} else {
4860 		sctp_wakeup_log(stcb, cum_ack, wake_him, SCTP_NOWAKE_FROM_SACK);
4861 #endif
4862 	}
4863 
4864 	if ((sctp_cmt_on_off == 0) && asoc->fast_retran_loss_recovery && accum_moved) {
4865 		if (compare_with_wrap(asoc->last_acked_seq,
4866 		    asoc->fast_recovery_tsn, MAX_TSN) ||
4867 		    asoc->last_acked_seq == asoc->fast_recovery_tsn) {
4868 			/* Setup so we will exit RFC2582 fast recovery */
4869 			will_exit_fast_recovery = 1;
4870 		}
4871 	}
4872 	/*
4873 	 * Check for revoked fragments:
4874 	 *
4875 	 * if Previous sack - Had no frags then we can't have any revoked if
4876 	 * Previous sack - Had frag's then - If we now have frags aka
4877 	 * num_seg > 0 call sctp_check_for_revoked() to tell if peer revoked
4878 	 * some of them. else - The peer revoked all ACKED fragments, since
4879 	 * we had some before and now we have NONE.
4880 	 */
4881 
4882 	if (sctp_cmt_on_off) {
4883 		/*
4884 		 * Don't check for revoked if CMT is ON. CMT causes
4885 		 * reordering of data and acks (received on different
4886 		 * interfaces) can be persistently reordered. Acking
4887 		 * followed by apparent revoking and re-acking causes
4888 		 * unexpected weird behavior. So, at this time, CMT does not
4889 		 * respect renegs. Renegs will have to be recovered through
4890 		 * a timeout. Not a big deal for such a rare event.
4891 		 */
4892 	} else if (num_seg)
4893 		sctp_check_for_revoked(asoc, cum_ack, biggest_tsn_acked);
4894 	else if (asoc->saw_sack_with_frags) {
4895 		int cnt_revoked = 0;
4896 
4897 		tp1 = TAILQ_FIRST(&asoc->sent_queue);
4898 		if (tp1 != NULL) {
4899 			/* Peer revoked all dg's marked or acked */
4900 			TAILQ_FOREACH(tp1, &asoc->sent_queue, sctp_next) {
4901 				if ((tp1->sent > SCTP_DATAGRAM_RESEND) &&
4902 				    (tp1->sent < SCTP_FORWARD_TSN_SKIP)) {
4903 					tp1->sent = SCTP_DATAGRAM_SENT;
4904 					tp1->rec.data.chunk_was_revoked = 1;
4905 					tp1->whoTo->flight_size += tp1->book_size;
4906 					asoc->total_flight_count++;
4907 					asoc->total_flight += tp1->book_size;
4908 					cnt_revoked++;
4909 				}
4910 			}
4911 			if (cnt_revoked) {
4912 				reneged_all = 1;
4913 			}
4914 		}
4915 		asoc->saw_sack_with_frags = 0;
4916 	}
4917 	if (num_seg)
4918 		asoc->saw_sack_with_frags = 1;
4919 	else
4920 		asoc->saw_sack_with_frags = 0;
4921 
4922 
4923 	sctp_cwnd_update(stcb, asoc, accum_moved, reneged_all, will_exit_fast_recovery);
4924 
4925 	if (TAILQ_EMPTY(&asoc->sent_queue)) {
4926 		/* nothing left in-flight */
4927 		TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
4928 			/* stop all timers */
4929 			if (sctp_early_fr) {
4930 				if (callout_pending(&net->fr_timer.timer)) {
4931 					SCTP_STAT_INCR(sctps_earlyfrstpidsck4);
4932 					sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
4933 					    SCTP_FROM_SCTP_INDATA + SCTP_LOC_29);
4934 				}
4935 			}
4936 			sctp_timer_stop(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
4937 			    stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_30);
4938 			net->flight_size = 0;
4939 			net->partial_bytes_acked = 0;
4940 		}
4941 		asoc->total_flight = 0;
4942 		asoc->total_flight_count = 0;
4943 	}
4944 	/**********************************/
4945 	/* Now what about shutdown issues */
4946 	/**********************************/
4947 	if (TAILQ_EMPTY(&asoc->send_queue) && TAILQ_EMPTY(&asoc->sent_queue)) {
4948 		/* nothing left on sendqueue.. consider done */
4949 #ifdef SCTP_LOG_RWND
4950 		sctp_log_rwnd_set(SCTP_SET_PEER_RWND_VIA_SACK,
4951 		    asoc->peers_rwnd, 0, 0, a_rwnd);
4952 #endif
4953 		asoc->peers_rwnd = a_rwnd;
4954 		if (asoc->peers_rwnd < stcb->sctp_ep->sctp_ep.sctp_sws_sender) {
4955 			/* SWS sender side engages */
4956 			asoc->peers_rwnd = 0;
4957 		}
4958 		/* clean up */
4959 		if ((asoc->stream_queue_cnt == 1) &&
4960 		    ((asoc->state & SCTP_STATE_SHUTDOWN_PENDING) ||
4961 		    (asoc->state & SCTP_STATE_SHUTDOWN_RECEIVED)) &&
4962 		    (asoc->locked_on_sending)
4963 		    ) {
4964 			struct sctp_stream_queue_pending *sp;
4965 
4966 			/*
4967 			 * I may be in a state where we got all across.. but
4968 			 * cannot write more due to a shutdown... we abort
4969 			 * since the user did not indicate EOR in this case.
4970 			 */
4971 			sp = TAILQ_LAST(&((asoc->locked_on_sending)->outqueue),
4972 			    sctp_streamhead);
4973 			if ((sp) && (sp->length == 0) && (sp->msg_is_complete == 0)) {
4974 				asoc->state |= SCTP_STATE_PARTIAL_MSG_LEFT;
4975 				asoc->locked_on_sending = NULL;
4976 				asoc->stream_queue_cnt--;
4977 			}
4978 		}
4979 		if ((asoc->state & SCTP_STATE_SHUTDOWN_PENDING) &&
4980 		    (asoc->stream_queue_cnt == 0)) {
4981 			if (asoc->state & SCTP_STATE_PARTIAL_MSG_LEFT) {
4982 				/* Need to abort here */
4983 				struct mbuf *oper;
4984 
4985 		abort_out_now:
4986 				*abort_now = 1;
4987 				/* XXX */
4988 				oper = sctp_get_mbuf_for_msg((sizeof(struct sctp_paramhdr) + sizeof(uint32_t)),
4989 				    0, M_DONTWAIT, 1, MT_DATA);
4990 				if (oper) {
4991 					struct sctp_paramhdr *ph;
4992 					uint32_t *ippp;
4993 
4994 					oper->m_len = sizeof(struct sctp_paramhdr) +
4995 					    sizeof(uint32_t);
4996 					ph = mtod(oper, struct sctp_paramhdr *);
4997 					ph->param_type = htons(SCTP_CAUSE_USER_INITIATED_ABT);
4998 					ph->param_length = htons(oper->m_len);
4999 					ippp = (uint32_t *) (ph + 1);
5000 					*ippp = htonl(SCTP_FROM_SCTP_INDATA + SCTP_LOC_31);
5001 				}
5002 				stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_31;
5003 				sctp_abort_an_association(stcb->sctp_ep, stcb, SCTP_RESPONSE_TO_USER_REQ, oper);
5004 				return;
5005 			} else {
5006 				asoc->state = SCTP_STATE_SHUTDOWN_SENT;
5007 				SCTP_STAT_DECR_GAUGE32(sctps_currestab);
5008 				sctp_stop_timers_for_shutdown(stcb);
5009 				sctp_send_shutdown(stcb,
5010 				    stcb->asoc.primary_destination);
5011 				sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWN,
5012 				    stcb->sctp_ep, stcb, asoc->primary_destination);
5013 				sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
5014 				    stcb->sctp_ep, stcb, asoc->primary_destination);
5015 			}
5016 			return;
5017 		} else if ((SCTP_GET_STATE(asoc) == SCTP_STATE_SHUTDOWN_RECEIVED) &&
5018 		    (asoc->stream_queue_cnt == 0)) {
5019 			if (asoc->state & SCTP_STATE_PARTIAL_MSG_LEFT) {
5020 				goto abort_out_now;
5021 			}
5022 			asoc->state = SCTP_STATE_SHUTDOWN_ACK_SENT;
5023 			SCTP_STAT_DECR_GAUGE32(sctps_currestab);
5024 			sctp_send_shutdown_ack(stcb,
5025 			    stcb->asoc.primary_destination);
5026 
5027 			sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNACK,
5028 			    stcb->sctp_ep, stcb, asoc->primary_destination);
5029 			return;
5030 		}
5031 	}
5032 	/*
5033 	 * Now here we are going to recycle net_ack for a different use...
5034 	 * HEADS UP.
5035 	 */
5036 	TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
5037 		net->net_ack = 0;
5038 	}
5039 
5040 	/*
5041 	 * CMT DAC algorithm: If SACK DAC flag was 0, then no extra marking
5042 	 * to be done. Setting this_sack_lowest_newack to the cum_ack will
5043 	 * automatically ensure that.
5044 	 */
5045 	if (sctp_cmt_on_off && sctp_cmt_use_dac && (cmt_dac_flag == 0)) {
5046 		this_sack_lowest_newack = cum_ack;
5047 	}
5048 	if (num_seg > 0) {
5049 		sctp_strike_gap_ack_chunks(stcb, asoc, biggest_tsn_acked,
5050 		    biggest_tsn_newly_acked, this_sack_lowest_newack, accum_moved);
5051 	}
5052 	/*********************************************/
5053 	/* Here we perform PR-SCTP procedures        */
5054 	/* (section 4.2)                             */
5055 	/*********************************************/
5056 	/* C1. update advancedPeerAckPoint */
5057 	if (compare_with_wrap(cum_ack, asoc->advanced_peer_ack_point, MAX_TSN)) {
5058 		asoc->advanced_peer_ack_point = cum_ack;
5059 	}
5060 	/* C2. try to further move advancedPeerAckPoint ahead */
5061 
5062 	if ((asoc->peer_supports_prsctp) && (asoc->pr_sctp_cnt > 0)) {
5063 		struct sctp_tmit_chunk *lchk;
5064 
5065 		lchk = sctp_try_advance_peer_ack_point(stcb, asoc);
5066 		/* C3. See if we need to send a Fwd-TSN */
5067 		if (compare_with_wrap(asoc->advanced_peer_ack_point, cum_ack,
5068 		    MAX_TSN)) {
5069 			/*
5070 			 * ISSUE with ECN, see FWD-TSN processing for notes
5071 			 * on issues that will occur when the ECN NONCE
5072 			 * stuff is put into SCTP for cross checking.
5073 			 */
5074 			send_forward_tsn(stcb, asoc);
5075 
5076 			/*
5077 			 * ECN Nonce: Disable Nonce Sum check when FWD TSN
5078 			 * is sent and store resync tsn
5079 			 */
5080 			asoc->nonce_sum_check = 0;
5081 			asoc->nonce_resync_tsn = asoc->advanced_peer_ack_point;
5082 			if (lchk) {
5083 				/* Assure a timer is up */
5084 				sctp_timer_start(SCTP_TIMER_TYPE_SEND,
5085 				    stcb->sctp_ep, stcb, lchk->whoTo);
5086 			}
5087 		}
5088 	}
5089 	/*
5090 	 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off == 1) &&
5091 	 * (net->fast_retran_loss_recovery == 0)))
5092 	 */
5093 	TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
5094 		if ((asoc->fast_retran_loss_recovery == 0) || (sctp_cmt_on_off == 1)) {
5095 			/* out of a RFC2582 Fast recovery window? */
5096 			if (net->net_ack > 0) {
5097 				/*
5098 				 * per section 7.2.3, are there any
5099 				 * destinations that had a fast retransmit
5100 				 * to them. If so what we need to do is
5101 				 * adjust ssthresh and cwnd.
5102 				 */
5103 				struct sctp_tmit_chunk *lchk;
5104 
5105 #ifdef  SCTP_HIGH_SPEED
5106 				sctp_hs_cwnd_decrease(stcb, net);
5107 #else
5108 #ifdef SCTP_CWND_MONITOR
5109 				int old_cwnd = net->cwnd;
5110 
5111 #endif
5112 				net->ssthresh = net->cwnd / 2;
5113 				if (net->ssthresh < (net->mtu * 2)) {
5114 					net->ssthresh = 2 * net->mtu;
5115 				}
5116 				net->cwnd = net->ssthresh;
5117 #ifdef SCTP_CWND_MONITOR
5118 				sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd),
5119 				    SCTP_CWND_LOG_FROM_FR);
5120 #endif
5121 #endif
5122 
5123 				lchk = TAILQ_FIRST(&asoc->send_queue);
5124 
5125 				net->partial_bytes_acked = 0;
5126 				/* Turn on fast recovery window */
5127 				asoc->fast_retran_loss_recovery = 1;
5128 				if (lchk == NULL) {
5129 					/* Mark end of the window */
5130 					asoc->fast_recovery_tsn = asoc->sending_seq - 1;
5131 				} else {
5132 					asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
5133 				}
5134 
5135 				/*
5136 				 * CMT fast recovery -- per destination
5137 				 * recovery variable.
5138 				 */
5139 				net->fast_retran_loss_recovery = 1;
5140 
5141 				if (lchk == NULL) {
5142 					/* Mark end of the window */
5143 					net->fast_recovery_tsn = asoc->sending_seq - 1;
5144 				} else {
5145 					net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
5146 				}
5147 
5148 
5149 
5150 				/*
5151 				 * Disable Nonce Sum Checking and store the
5152 				 * resync tsn
5153 				 */
5154 				asoc->nonce_sum_check = 0;
5155 				asoc->nonce_resync_tsn = asoc->fast_recovery_tsn + 1;
5156 
5157 				sctp_timer_stop(SCTP_TIMER_TYPE_SEND,
5158 				    stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
5159 				sctp_timer_start(SCTP_TIMER_TYPE_SEND,
5160 				    stcb->sctp_ep, stcb, net);
5161 			}
5162 		} else if (net->net_ack > 0) {
5163 			/*
5164 			 * Mark a peg that we WOULD have done a cwnd
5165 			 * reduction but RFC2582 prevented this action.
5166 			 */
5167 			SCTP_STAT_INCR(sctps_fastretransinrtt);
5168 		}
5169 	}
5170 
5171 
5172 	/******************************************************************
5173 	 *  Here we do the stuff with ECN Nonce checking.
5174 	 *  We basically check to see if the nonce sum flag was incorrect
5175 	 *  or if resynchronization needs to be done. Also if we catch a
5176 	 *  misbehaving receiver we give him the kick.
5177 	 ******************************************************************/
5178 
5179 	if (asoc->ecn_nonce_allowed) {
5180 		if (asoc->nonce_sum_check) {
5181 			if (nonce_sum_flag != ((asoc->nonce_sum_expect_base + ecn_seg_sums) & SCTP_SACK_NONCE_SUM)) {
5182 				if (asoc->nonce_wait_for_ecne == 0) {
5183 					struct sctp_tmit_chunk *lchk;
5184 
5185 					lchk = TAILQ_FIRST(&asoc->send_queue);
5186 					asoc->nonce_wait_for_ecne = 1;
5187 					if (lchk) {
5188 						asoc->nonce_wait_tsn = lchk->rec.data.TSN_seq;
5189 					} else {
5190 						asoc->nonce_wait_tsn = asoc->sending_seq;
5191 					}
5192 				} else {
5193 					if (compare_with_wrap(asoc->last_acked_seq, asoc->nonce_wait_tsn, MAX_TSN) ||
5194 					    (asoc->last_acked_seq == asoc->nonce_wait_tsn)) {
5195 						/*
5196 						 * Misbehaving peer. We need
5197 						 * to react to this guy
5198 						 */
5199 						asoc->ecn_allowed = 0;
5200 						asoc->ecn_nonce_allowed = 0;
5201 					}
5202 				}
5203 			}
5204 		} else {
5205 			/* See if Resynchronization Possible */
5206 			if (compare_with_wrap(asoc->last_acked_seq, asoc->nonce_resync_tsn, MAX_TSN)) {
5207 				asoc->nonce_sum_check = 1;
5208 				/*
5209 				 * now we must calculate what the base is.
5210 				 * We do this based on two things, we know
5211 				 * the total's for all the segments
5212 				 * gap-acked in the SACK, its stored in
5213 				 * ecn_seg_sums. We also know the SACK's
5214 				 * nonce sum, its in nonce_sum_flag. So we
5215 				 * can build a truth table to back-calculate
5216 				 * the new value of
5217 				 * asoc->nonce_sum_expect_base:
5218 				 *
5219 				 * SACK-flag-Value         Seg-Sums Base 0 0 0
5220 				 * 1                    0 1 0 1 1 1
5221 				 * 1 0
5222 				 */
5223 				asoc->nonce_sum_expect_base = (ecn_seg_sums ^ nonce_sum_flag) & SCTP_SACK_NONCE_SUM;
5224 			}
5225 		}
5226 	}
5227 	/* Now are we exiting loss recovery ? */
5228 	if (will_exit_fast_recovery) {
5229 		/* Ok, we must exit fast recovery */
5230 		asoc->fast_retran_loss_recovery = 0;
5231 	}
5232 	if ((asoc->sat_t3_loss_recovery) &&
5233 	    ((compare_with_wrap(asoc->last_acked_seq, asoc->sat_t3_recovery_tsn,
5234 	    MAX_TSN) ||
5235 	    (asoc->last_acked_seq == asoc->sat_t3_recovery_tsn)))) {
5236 		/* end satellite t3 loss recovery */
5237 		asoc->sat_t3_loss_recovery = 0;
5238 	}
5239 	TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
5240 		if (net->will_exit_fast_recovery) {
5241 			/* Ok, we must exit fast recovery */
5242 			net->fast_retran_loss_recovery = 0;
5243 		}
5244 	}
5245 
5246 	/* Adjust and set the new rwnd value */
5247 #ifdef SCTP_LOG_RWND
5248 	sctp_log_rwnd_set(SCTP_SET_PEER_RWND_VIA_SACK,
5249 	    asoc->peers_rwnd, asoc->total_flight, (asoc->sent_queue_cnt * sctp_peer_chunk_oh), a_rwnd);
5250 #endif
5251 
5252 	asoc->peers_rwnd = sctp_sbspace_sub(a_rwnd,
5253 	    (uint32_t) (asoc->total_flight + (asoc->sent_queue_cnt * sctp_peer_chunk_oh)));
5254 	if (asoc->peers_rwnd < stcb->sctp_ep->sctp_ep.sctp_sws_sender) {
5255 		/* SWS sender side engages */
5256 		asoc->peers_rwnd = 0;
5257 	}
5258 	/*
5259 	 * Now we must setup so we have a timer up for anyone with
5260 	 * outstanding data.
5261 	 */
5262 again:
5263 	j = 0;
5264 	TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
5265 		if (net->flight_size) {
5266 			j++;
5267 			sctp_timer_start(SCTP_TIMER_TYPE_SEND,
5268 			    stcb->sctp_ep, stcb, net);
5269 		}
5270 	}
5271 	if ((j == 0) && (!TAILQ_EMPTY(&asoc->sent_queue)) && (asoc->sent_queue_retran_cnt == 0)) {
5272 		/* huh, this should not happen */
5273 #ifdef INVARIANTS
5274 		panic("Flight size incorrect? fixing??");
5275 #else
5276 		printf("Flight size incorrect? fixing??\n");
5277 		TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
5278 			net->flight_size = 0;
5279 		}
5280 		asoc->total_flight = 0;
5281 		asoc->total_flight_count = 0;
5282 		asoc->sent_queue_retran_cnt = 0;
5283 		TAILQ_FOREACH(tp1, &asoc->sent_queue, sctp_next) {
5284 			if (tp1->sent < SCTP_DATAGRAM_RESEND) {
5285 				tp1->whoTo->flight_size += tp1->book_size;
5286 				asoc->total_flight += tp1->book_size;
5287 				asoc->total_flight_count++;
5288 			} else if (tp1->sent == SCTP_DATAGRAM_RESEND) {
5289 				asoc->sent_queue_retran_cnt++;
5290 			}
5291 		}
5292 #endif
5293 		goto again;
5294 	}
5295 #ifdef SCTP_SACK_RWND_LOGGING
5296 	sctp_misc_ints(SCTP_SACK_RWND_UPDATE,
5297 	    a_rwnd,
5298 	    stcb->asoc.peers_rwnd,
5299 	    stcb->asoc.total_flight,
5300 	    stcb->asoc.total_output_queue_size);
5301 
5302 #endif
5303 
5304 }
5305 
5306 void
5307 sctp_update_acked(struct sctp_tcb *stcb, struct sctp_shutdown_chunk *cp,
5308     struct sctp_nets *netp, int *abort_flag)
5309 {
5310 	/* Copy cum-ack */
5311 	uint32_t cum_ack, a_rwnd;
5312 
5313 	cum_ack = ntohl(cp->cumulative_tsn_ack);
5314 	/* Arrange so a_rwnd does NOT change */
5315 	a_rwnd = stcb->asoc.peers_rwnd + stcb->asoc.total_flight;
5316 
5317 	/* Now call the express sack handling */
5318 	sctp_express_handle_sack(stcb, cum_ack, a_rwnd, 0, abort_flag);
5319 }
5320 
5321 static void
5322 sctp_kick_prsctp_reorder_queue(struct sctp_tcb *stcb,
5323     struct sctp_stream_in *strmin)
5324 {
5325 	struct sctp_queued_to_read *ctl, *nctl;
5326 	struct sctp_association *asoc;
5327 	int tt;
5328 
5329 	asoc = &stcb->asoc;
5330 	tt = strmin->last_sequence_delivered;
5331 	/*
5332 	 * First deliver anything prior to and including the stream no that
5333 	 * came in
5334 	 */
5335 	ctl = TAILQ_FIRST(&strmin->inqueue);
5336 	while (ctl) {
5337 		nctl = TAILQ_NEXT(ctl, next);
5338 		if (compare_with_wrap(tt, ctl->sinfo_ssn, MAX_SEQ) ||
5339 		    (tt == ctl->sinfo_ssn)) {
5340 			/* this is deliverable now */
5341 			TAILQ_REMOVE(&strmin->inqueue, ctl, next);
5342 			/* subtract pending on streams */
5343 			asoc->size_on_all_streams -= ctl->length;
5344 			sctp_ucount_decr(asoc->cnt_on_all_streams);
5345 			/* deliver it to at least the delivery-q */
5346 			if (stcb->sctp_socket) {
5347 				sctp_add_to_readq(stcb->sctp_ep, stcb,
5348 				    ctl,
5349 				    &stcb->sctp_socket->so_rcv, 1);
5350 			}
5351 		} else {
5352 			/* no more delivery now. */
5353 			break;
5354 		}
5355 		ctl = nctl;
5356 	}
5357 	/*
5358 	 * now we must deliver things in queue the normal way  if any are
5359 	 * now ready.
5360 	 */
5361 	tt = strmin->last_sequence_delivered + 1;
5362 	ctl = TAILQ_FIRST(&strmin->inqueue);
5363 	while (ctl) {
5364 		nctl = TAILQ_NEXT(ctl, next);
5365 		if (tt == ctl->sinfo_ssn) {
5366 			/* this is deliverable now */
5367 			TAILQ_REMOVE(&strmin->inqueue, ctl, next);
5368 			/* subtract pending on streams */
5369 			asoc->size_on_all_streams -= ctl->length;
5370 			sctp_ucount_decr(asoc->cnt_on_all_streams);
5371 			/* deliver it to at least the delivery-q */
5372 			strmin->last_sequence_delivered = ctl->sinfo_ssn;
5373 			if (stcb->sctp_socket) {
5374 				sctp_add_to_readq(stcb->sctp_ep, stcb,
5375 				    ctl,
5376 				    &stcb->sctp_socket->so_rcv, 1);
5377 			}
5378 			tt = strmin->last_sequence_delivered + 1;
5379 		} else {
5380 			break;
5381 		}
5382 		ctl = nctl;
5383 	}
5384 }
5385 
5386 void
5387 sctp_handle_forward_tsn(struct sctp_tcb *stcb,
5388     struct sctp_forward_tsn_chunk *fwd, int *abort_flag)
5389 {
5390 	/*
5391 	 * ISSUES that MUST be fixed for ECN! When we are the sender of the
5392 	 * forward TSN, when the SACK comes back that acknowledges the
5393 	 * FWD-TSN we must reset the NONCE sum to match correctly. This will
5394 	 * get quite tricky since we may have sent more data interveneing
5395 	 * and must carefully account for what the SACK says on the nonce
5396 	 * and any gaps that are reported. This work will NOT be done here,
5397 	 * but I note it here since it is really related to PR-SCTP and
5398 	 * FWD-TSN's
5399 	 */
5400 
5401 	/* The pr-sctp fwd tsn */
5402 	/*
5403 	 * here we will perform all the data receiver side steps for
5404 	 * processing FwdTSN, as required in by pr-sctp draft:
5405 	 *
5406 	 * Assume we get FwdTSN(x):
5407 	 *
5408 	 * 1) update local cumTSN to x 2) try to further advance cumTSN to x +
5409 	 * others we have 3) examine and update re-ordering queue on
5410 	 * pr-in-streams 4) clean up re-assembly queue 5) Send a sack to
5411 	 * report where we are.
5412 	 */
5413 	struct sctp_strseq *stseq;
5414 	struct sctp_association *asoc;
5415 	uint32_t new_cum_tsn, gap, back_out_htsn;
5416 	unsigned int i, cnt_gone, fwd_sz, cumack_set_flag, m_size;
5417 	struct sctp_stream_in *strm;
5418 	struct sctp_tmit_chunk *chk, *at;
5419 
5420 	cumack_set_flag = 0;
5421 	asoc = &stcb->asoc;
5422 	cnt_gone = 0;
5423 	if ((fwd_sz = ntohs(fwd->ch.chunk_length)) < sizeof(struct sctp_forward_tsn_chunk)) {
5424 #ifdef SCTP_DEBUG
5425 		if (sctp_debug_on & SCTP_DEBUG_INDATA1) {
5426 			printf("Bad size too small/big fwd-tsn\n");
5427 		}
5428 #endif
5429 		return;
5430 	}
5431 	m_size = (stcb->asoc.mapping_array_size << 3);
5432 	/*************************************************************/
5433 	/* 1. Here we update local cumTSN and shift the bitmap array */
5434 	/*************************************************************/
5435 	new_cum_tsn = ntohl(fwd->new_cumulative_tsn);
5436 
5437 	if (compare_with_wrap(asoc->cumulative_tsn, new_cum_tsn, MAX_TSN) ||
5438 	    asoc->cumulative_tsn == new_cum_tsn) {
5439 		/* Already got there ... */
5440 		return;
5441 	}
5442 	back_out_htsn = asoc->highest_tsn_inside_map;
5443 	if (compare_with_wrap(new_cum_tsn, asoc->highest_tsn_inside_map,
5444 	    MAX_TSN)) {
5445 		asoc->highest_tsn_inside_map = new_cum_tsn;
5446 #ifdef SCTP_MAP_LOGGING
5447 		sctp_log_map(0, 0, asoc->highest_tsn_inside_map, SCTP_MAP_SLIDE_RESULT);
5448 #endif
5449 	}
5450 	/*
5451 	 * now we know the new TSN is more advanced, let's find the actual
5452 	 * gap
5453 	 */
5454 	if ((compare_with_wrap(new_cum_tsn, asoc->mapping_array_base_tsn,
5455 	    MAX_TSN)) ||
5456 	    (new_cum_tsn == asoc->mapping_array_base_tsn)) {
5457 		gap = new_cum_tsn - asoc->mapping_array_base_tsn;
5458 	} else {
5459 		/* try to prevent underflow here */
5460 		gap = new_cum_tsn + (MAX_TSN - asoc->mapping_array_base_tsn) + 1;
5461 	}
5462 
5463 	if (gap > m_size || gap < 0) {
5464 		asoc->highest_tsn_inside_map = back_out_htsn;
5465 		if ((long)gap > sctp_sbspace(&stcb->asoc, &stcb->sctp_socket->so_rcv)) {
5466 			/*
5467 			 * out of range (of single byte chunks in the rwnd I
5468 			 * give out) too questionable. better to drop it
5469 			 * silently
5470 			 */
5471 			return;
5472 		}
5473 		if (asoc->highest_tsn_inside_map >
5474 		    asoc->mapping_array_base_tsn) {
5475 			gap = asoc->highest_tsn_inside_map -
5476 			    asoc->mapping_array_base_tsn;
5477 		} else {
5478 			gap = asoc->highest_tsn_inside_map +
5479 			    (MAX_TSN - asoc->mapping_array_base_tsn) + 1;
5480 		}
5481 		cumack_set_flag = 1;
5482 	}
5483 	for (i = 0; i <= gap; i++) {
5484 		SCTP_SET_TSN_PRESENT(asoc->mapping_array, i);
5485 	}
5486 	/*
5487 	 * Now after marking all, slide thing forward but no sack please.
5488 	 */
5489 	sctp_sack_check(stcb, 0, 0, abort_flag);
5490 	if (*abort_flag)
5491 		return;
5492 
5493 	if (cumack_set_flag) {
5494 		/*
5495 		 * fwd-tsn went outside my gap array - not a common
5496 		 * occurance. Do the same thing we do when a cookie-echo
5497 		 * arrives.
5498 		 */
5499 		asoc->highest_tsn_inside_map = new_cum_tsn - 1;
5500 		asoc->mapping_array_base_tsn = new_cum_tsn;
5501 		asoc->cumulative_tsn = asoc->highest_tsn_inside_map;
5502 #ifdef SCTP_MAP_LOGGING
5503 		sctp_log_map(0, 3, asoc->highest_tsn_inside_map, SCTP_MAP_SLIDE_RESULT);
5504 #endif
5505 		asoc->last_echo_tsn = asoc->highest_tsn_inside_map;
5506 	}
5507 	/*************************************************************/
5508 	/* 2. Clear up re-assembly queue                             */
5509 	/*************************************************************/
5510 
5511 	/*
5512 	 * First service it if pd-api is up, just in case we can progress it
5513 	 * forward
5514 	 */
5515 	if (asoc->fragmented_delivery_inprogress) {
5516 		sctp_service_reassembly(stcb, asoc);
5517 	}
5518 	if (!TAILQ_EMPTY(&asoc->reasmqueue)) {
5519 		/* For each one on here see if we need to toss it */
5520 		/*
5521 		 * For now large messages held on the reasmqueue that are
5522 		 * complete will be tossed too. We could in theory do more
5523 		 * work to spin through and stop after dumping one msg aka
5524 		 * seeing the start of a new msg at the head, and call the
5525 		 * delivery function... to see if it can be delivered... But
5526 		 * for now we just dump everything on the queue.
5527 		 */
5528 		chk = TAILQ_FIRST(&asoc->reasmqueue);
5529 		while (chk) {
5530 			at = TAILQ_NEXT(chk, sctp_next);
5531 			if (compare_with_wrap(asoc->cumulative_tsn,
5532 			    chk->rec.data.TSN_seq, MAX_TSN) ||
5533 			    asoc->cumulative_tsn == chk->rec.data.TSN_seq) {
5534 				/* It needs to be tossed */
5535 				TAILQ_REMOVE(&asoc->reasmqueue, chk, sctp_next);
5536 				if (compare_with_wrap(chk->rec.data.TSN_seq,
5537 				    asoc->tsn_last_delivered, MAX_TSN)) {
5538 					asoc->tsn_last_delivered =
5539 					    chk->rec.data.TSN_seq;
5540 					asoc->str_of_pdapi =
5541 					    chk->rec.data.stream_number;
5542 					asoc->ssn_of_pdapi =
5543 					    chk->rec.data.stream_seq;
5544 					asoc->fragment_flags =
5545 					    chk->rec.data.rcv_flags;
5546 				}
5547 				asoc->size_on_reasm_queue -= chk->send_size;
5548 				sctp_ucount_decr(asoc->cnt_on_reasm_queue);
5549 				cnt_gone++;
5550 
5551 				/* Clear up any stream problem */
5552 				if ((chk->rec.data.rcv_flags & SCTP_DATA_UNORDERED) !=
5553 				    SCTP_DATA_UNORDERED &&
5554 				    (compare_with_wrap(chk->rec.data.stream_seq,
5555 				    asoc->strmin[chk->rec.data.stream_number].last_sequence_delivered,
5556 				    MAX_SEQ))) {
5557 					/*
5558 					 * We must dump forward this streams
5559 					 * sequence number if the chunk is
5560 					 * not unordered that is being
5561 					 * skipped. There is a chance that
5562 					 * if the peer does not include the
5563 					 * last fragment in its FWD-TSN we
5564 					 * WILL have a problem here since
5565 					 * you would have a partial chunk in
5566 					 * queue that may not be
5567 					 * deliverable. Also if a Partial
5568 					 * delivery API as started the user
5569 					 * may get a partial chunk. The next
5570 					 * read returning a new chunk...
5571 					 * really ugly but I see no way
5572 					 * around it! Maybe a notify??
5573 					 */
5574 					asoc->strmin[chk->rec.data.stream_number].last_sequence_delivered =
5575 					    chk->rec.data.stream_seq;
5576 				}
5577 				if (chk->data) {
5578 					sctp_m_freem(chk->data);
5579 					chk->data = NULL;
5580 				}
5581 				sctp_free_remote_addr(chk->whoTo);
5582 				sctp_free_a_chunk(stcb, chk);
5583 			} else {
5584 				/*
5585 				 * Ok we have gone beyond the end of the
5586 				 * fwd-tsn's mark. Some checks...
5587 				 */
5588 				if ((asoc->fragmented_delivery_inprogress) &&
5589 				    (chk->rec.data.rcv_flags & SCTP_DATA_FIRST_FRAG)) {
5590 					/*
5591 					 * Special case PD-API is up and
5592 					 * what we fwd-tsn' over includes
5593 					 * one that had the LAST_FRAG. We no
5594 					 * longer need to do the PD-API.
5595 					 */
5596 					asoc->fragmented_delivery_inprogress = 0;
5597 					sctp_ulp_notify(SCTP_NOTIFY_PARTIAL_DELVIERY_INDICATION,
5598 					    stcb, SCTP_PARTIAL_DELIVERY_ABORTED, (void *)NULL);
5599 
5600 				}
5601 				break;
5602 			}
5603 			chk = at;
5604 		}
5605 	}
5606 	if (asoc->fragmented_delivery_inprogress) {
5607 		/*
5608 		 * Ok we removed cnt_gone chunks in the PD-API queue that
5609 		 * were being delivered. So now we must turn off the flag.
5610 		 */
5611 		sctp_ulp_notify(SCTP_NOTIFY_PARTIAL_DELVIERY_INDICATION,
5612 		    stcb, SCTP_PARTIAL_DELIVERY_ABORTED, (void *)NULL);
5613 		asoc->fragmented_delivery_inprogress = 0;
5614 	}
5615 	/*************************************************************/
5616 	/* 3. Update the PR-stream re-ordering queues                */
5617 	/*************************************************************/
5618 	stseq = (struct sctp_strseq *)((caddr_t)fwd + sizeof(*fwd));
5619 	fwd_sz -= sizeof(*fwd);
5620 	{
5621 		/* New method. */
5622 		int num_str, i;
5623 
5624 		num_str = fwd_sz / sizeof(struct sctp_strseq);
5625 		for (i = 0; i < num_str; i++) {
5626 			uint16_t st;
5627 			unsigned char *xx;
5628 
5629 			/* Convert */
5630 			xx = (unsigned char *)&stseq[i];
5631 			st = ntohs(stseq[i].stream);
5632 			stseq[i].stream = st;
5633 			st = ntohs(stseq[i].sequence);
5634 			stseq[i].sequence = st;
5635 			/* now process */
5636 			if (stseq[i].stream > asoc->streamincnt) {
5637 				/*
5638 				 * It is arguable if we should continue.
5639 				 * Since the peer sent bogus stream info we
5640 				 * may be in deep trouble.. a return may be
5641 				 * a better choice?
5642 				 */
5643 				continue;
5644 			}
5645 			strm = &asoc->strmin[stseq[i].stream];
5646 			if (compare_with_wrap(stseq[i].sequence,
5647 			    strm->last_sequence_delivered, MAX_SEQ)) {
5648 				/* Update the sequence number */
5649 				strm->last_sequence_delivered =
5650 				    stseq[i].sequence;
5651 			}
5652 			/* now kick the stream the new way */
5653 			sctp_kick_prsctp_reorder_queue(stcb, strm);
5654 		}
5655 	}
5656 }
5657