xref: /freebsd/sys/netinet/sctp_input.c (revision 2b743a9e9ddc6736208dc8ca1ce06ce64ad20a19)
1 /*-
2  * Copyright (c) 2001-2007, 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_input.c,v 1.27 2005/03/06 16:04:17 itojun Exp $	 */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <netinet/sctp_os.h>
37 #include <netinet/sctp_var.h>
38 #include <netinet/sctp_pcb.h>
39 #include <netinet/sctp_header.h>
40 #include <netinet/sctputil.h>
41 #include <netinet/sctp_output.h>
42 #include <netinet/sctp_input.h>
43 #include <netinet/sctp_auth.h>
44 #include <netinet/sctp_indata.h>
45 #include <netinet/sctp_asconf.h>
46 
47 
48 #ifdef SCTP_DEBUG
49 extern uint32_t sctp_debug_on;
50 
51 #endif
52 
53 
54 
55 struct sctp_foo_stuff sctp_logoff[30000];
56 int sctp_logoff_stuff = 0;
57 
58 
59 static void
60 sctp_stop_all_cookie_timers(struct sctp_tcb *stcb)
61 {
62 	struct sctp_nets *net;
63 
64 	/*
65 	 * This now not only stops all cookie timers it also stops any INIT
66 	 * timers as well. This will make sure that the timers are stopped
67 	 * in all collision cases.
68 	 */
69 	SCTP_TCB_LOCK_ASSERT(stcb);
70 	TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) {
71 		if (net->rxt_timer.type == SCTP_TIMER_TYPE_COOKIE) {
72 			sctp_timer_stop(SCTP_TIMER_TYPE_COOKIE,
73 			    stcb->sctp_ep,
74 			    stcb,
75 			    net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_1);
76 		} else if (net->rxt_timer.type == SCTP_TIMER_TYPE_INIT) {
77 			sctp_timer_stop(SCTP_TIMER_TYPE_INIT,
78 			    stcb->sctp_ep,
79 			    stcb,
80 			    net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_2);
81 		}
82 	}
83 }
84 
85 /* INIT handler */
86 static void
87 sctp_handle_init(struct mbuf *m, int iphlen, int offset, struct sctphdr *sh,
88     struct sctp_init_chunk *cp, struct sctp_inpcb *inp, struct sctp_tcb *stcb,
89     struct sctp_nets *net)
90 {
91 	struct sctp_init *init;
92 	struct mbuf *op_err;
93 	uint32_t init_limit;
94 
95 #ifdef SCTP_DEBUG
96 	if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
97 		printf("sctp_handle_init: handling INIT tcb:%p\n", stcb);
98 	}
99 #endif
100 	op_err = NULL;
101 	init = &cp->init;
102 	/* First are we accepting? */
103 	if ((inp->sctp_socket->so_qlimit == 0) && (stcb == NULL)) {
104 #ifdef SCTP_DEBUG
105 		if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
106 			printf("sctp_handle_init: Abort, so_qlimit:%d\n", inp->sctp_socket->so_qlimit);
107 		}
108 #endif
109 		/*
110 		 * FIX ME ?? What about TCP model and we have a
111 		 * match/restart case?
112 		 */
113 		sctp_abort_association(inp, stcb, m, iphlen, sh, op_err);
114 		return;
115 	}
116 	if (ntohs(cp->ch.chunk_length) < sizeof(struct sctp_init_chunk)) {
117 		/* Invalid length */
118 		op_err = sctp_generate_invmanparam(SCTP_CAUSE_INVALID_PARAM);
119 		sctp_abort_association(inp, stcb, m, iphlen, sh, op_err);
120 		return;
121 	}
122 	/* validate parameters */
123 	if (init->initiate_tag == 0) {
124 		/* protocol error... send abort */
125 		op_err = sctp_generate_invmanparam(SCTP_CAUSE_INVALID_PARAM);
126 		sctp_abort_association(inp, stcb, m, iphlen, sh, op_err);
127 		return;
128 	}
129 	if (ntohl(init->a_rwnd) < SCTP_MIN_RWND) {
130 		/* invalid parameter... send abort */
131 		op_err = sctp_generate_invmanparam(SCTP_CAUSE_INVALID_PARAM);
132 		sctp_abort_association(inp, stcb, m, iphlen, sh, op_err);
133 		return;
134 	}
135 	if (init->num_inbound_streams == 0) {
136 		/* protocol error... send abort */
137 		op_err = sctp_generate_invmanparam(SCTP_CAUSE_INVALID_PARAM);
138 		sctp_abort_association(inp, stcb, m, iphlen, sh, op_err);
139 		return;
140 	}
141 	if (init->num_outbound_streams == 0) {
142 		/* protocol error... send abort */
143 		op_err = sctp_generate_invmanparam(SCTP_CAUSE_INVALID_PARAM);
144 		sctp_abort_association(inp, stcb, m, iphlen, sh, op_err);
145 		return;
146 	}
147 	init_limit = offset + ntohs(cp->ch.chunk_length);
148 	if (sctp_validate_init_auth_params(m, offset + sizeof(*cp),
149 	    init_limit)) {
150 		/* auth parameter(s) error... send abort */
151 		sctp_abort_association(inp, stcb, m, iphlen, sh, NULL);
152 		return;
153 	}
154 	/* send an INIT-ACK w/cookie */
155 #ifdef SCTP_DEBUG
156 	if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
157 		printf("sctp_handle_init: sending INIT-ACK\n");
158 	}
159 #endif
160 	sctp_send_initiate_ack(inp, stcb, m, iphlen, offset, sh, cp);
161 }
162 
163 /*
164  * process peer "INIT/INIT-ACK" chunk returns value < 0 on error
165  */
166 static int
167 sctp_process_init(struct sctp_init_chunk *cp, struct sctp_tcb *stcb,
168     struct sctp_nets *net)
169 {
170 	struct sctp_init *init;
171 	struct sctp_association *asoc;
172 	struct sctp_nets *lnet;
173 	unsigned int i;
174 
175 	init = &cp->init;
176 	asoc = &stcb->asoc;
177 	/* save off parameters */
178 	asoc->peer_vtag = ntohl(init->initiate_tag);
179 	asoc->peers_rwnd = ntohl(init->a_rwnd);
180 	if (TAILQ_FIRST(&asoc->nets)) {
181 		/* update any ssthresh's that may have a default */
182 		TAILQ_FOREACH(lnet, &asoc->nets, sctp_next) {
183 			lnet->ssthresh = asoc->peers_rwnd;
184 
185 #if defined(SCTP_CWND_MONITOR) || defined(SCTP_CWND_LOGGING)
186 			sctp_log_cwnd(stcb, lnet, 0, SCTP_CWND_INITIALIZATION);
187 #endif
188 
189 		}
190 	}
191 	SCTP_TCB_SEND_LOCK(stcb);
192 	if (asoc->pre_open_streams > ntohs(init->num_inbound_streams)) {
193 		unsigned int newcnt;
194 		struct sctp_stream_out *outs;
195 		struct sctp_stream_queue_pending *sp;
196 
197 		/* cut back on number of streams */
198 		newcnt = ntohs(init->num_inbound_streams);
199 		/* This if is probably not needed but I am cautious */
200 		if (asoc->strmout) {
201 			/* First make sure no data chunks are trapped */
202 			for (i = newcnt; i < asoc->pre_open_streams; i++) {
203 				outs = &asoc->strmout[i];
204 				sp = TAILQ_FIRST(&outs->outqueue);
205 				while (sp) {
206 					TAILQ_REMOVE(&outs->outqueue, sp,
207 					    next);
208 					asoc->stream_queue_cnt--;
209 					sctp_ulp_notify(SCTP_NOTIFY_SPECIAL_SP_FAIL,
210 					    stcb, SCTP_NOTIFY_DATAGRAM_UNSENT,
211 					    sp);
212 					if (sp->data) {
213 						sctp_m_freem(sp->data);
214 						sp->data = NULL;
215 					}
216 					sctp_free_remote_addr(sp->net);
217 					sp->net = NULL;
218 					/* Free the chunk */
219 					printf("sp:%p tcb:%p weird free case\n",
220 					    sp, stcb);
221 
222 					sctp_free_a_strmoq(stcb, sp);
223 					sp = TAILQ_FIRST(&outs->outqueue);
224 				}
225 			}
226 		}
227 		/* cut back the count and abandon the upper streams */
228 		asoc->pre_open_streams = newcnt;
229 	}
230 	SCTP_TCB_SEND_UNLOCK(stcb);
231 	asoc->streamoutcnt = asoc->pre_open_streams;
232 	/* init tsn's */
233 	asoc->highest_tsn_inside_map = asoc->asconf_seq_in = ntohl(init->initial_tsn) - 1;
234 #ifdef SCTP_MAP_LOGGING
235 	sctp_log_map(0, 5, asoc->highest_tsn_inside_map, SCTP_MAP_SLIDE_RESULT);
236 #endif
237 	/* This is the next one we expect */
238 	asoc->str_reset_seq_in = asoc->asconf_seq_in + 1;
239 
240 	asoc->mapping_array_base_tsn = ntohl(init->initial_tsn);
241 	asoc->cumulative_tsn = asoc->asconf_seq_in;
242 	asoc->last_echo_tsn = asoc->asconf_seq_in;
243 	asoc->advanced_peer_ack_point = asoc->last_acked_seq;
244 	/* open the requested streams */
245 	if (asoc->strmin != NULL) {
246 		/* Free the old ones */
247 		struct sctp_queued_to_read *ctl;
248 
249 		for (i = 0; i < asoc->streamincnt; i++) {
250 			ctl = TAILQ_FIRST(&asoc->strmin[i].inqueue);
251 			while (ctl) {
252 				TAILQ_REMOVE(&asoc->strmin[i].inqueue, ctl, next);
253 				sctp_free_remote_addr(ctl->whoFrom);
254 				sctp_m_freem(ctl->data);
255 				ctl->data = NULL;
256 				sctp_free_a_readq(stcb, ctl);
257 				ctl = TAILQ_FIRST(&asoc->strmin[i].inqueue);
258 			}
259 		}
260 		SCTP_FREE(asoc->strmin);
261 	}
262 	asoc->streamincnt = ntohs(init->num_outbound_streams);
263 	if (asoc->streamincnt > MAX_SCTP_STREAMS) {
264 		asoc->streamincnt = MAX_SCTP_STREAMS;
265 	}
266 	SCTP_MALLOC(asoc->strmin, struct sctp_stream_in *, asoc->streamincnt *
267 	    sizeof(struct sctp_stream_in), "StreamsIn");
268 	if (asoc->strmin == NULL) {
269 		/* we didn't get memory for the streams! */
270 #ifdef SCTP_DEBUG
271 		if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
272 			printf("process_init: couldn't get memory for the streams!\n");
273 		}
274 #endif
275 		return (-1);
276 	}
277 	for (i = 0; i < asoc->streamincnt; i++) {
278 		asoc->strmin[i].stream_no = i;
279 		asoc->strmin[i].last_sequence_delivered = 0xffff;
280 		/*
281 		 * U-stream ranges will be set when the cookie is unpacked.
282 		 * Or for the INIT sender they are un set (if pr-sctp not
283 		 * supported) when the INIT-ACK arrives.
284 		 */
285 		TAILQ_INIT(&asoc->strmin[i].inqueue);
286 		/*
287 		 * we are not on any wheel, pr-sctp streams will go on the
288 		 * wheel when they have data waiting for reorder.
289 		 */
290 		asoc->strmin[i].next_spoke.tqe_next = 0;
291 		asoc->strmin[i].next_spoke.tqe_prev = 0;
292 	}
293 
294 	/*
295 	 * load_address_from_init will put the addresses into the
296 	 * association when the COOKIE is processed or the INIT-ACK is
297 	 * processed. Both types of COOKIE's existing and new call this
298 	 * routine. It will remove addresses that are no longer in the
299 	 * association (for the restarting case where addresses are
300 	 * removed). Up front when the INIT arrives we will discard it if it
301 	 * is a restart and new addresses have been added.
302 	 */
303 	return (0);
304 }
305 
306 /*
307  * INIT-ACK message processing/consumption returns value < 0 on error
308  */
309 static int
310 sctp_process_init_ack(struct mbuf *m, int iphlen, int offset,
311     struct sctphdr *sh, struct sctp_init_ack_chunk *cp, struct sctp_tcb *stcb,
312     struct sctp_nets *net)
313 {
314 	struct sctp_association *asoc;
315 	struct mbuf *op_err;
316 	int retval, abort_flag;
317 	uint32_t initack_limit;
318 
319 	/* First verify that we have no illegal param's */
320 	abort_flag = 0;
321 	op_err = NULL;
322 
323 	op_err = sctp_arethere_unrecognized_parameters(m,
324 	    (offset + sizeof(struct sctp_init_chunk)),
325 	    &abort_flag, (struct sctp_chunkhdr *)cp);
326 	if (abort_flag) {
327 		/* Send an abort and notify peer */
328 		if (op_err != NULL) {
329 			sctp_send_operr_to(m, iphlen, op_err, cp->init.initiate_tag);
330 		} else {
331 			/*
332 			 * Just notify (abort_assoc does this if we send an
333 			 * abort).
334 			 */
335 			sctp_abort_notification(stcb, 0);
336 			/*
337 			 * No sense in further INIT's since we will get the
338 			 * same param back
339 			 */
340 			sctp_free_assoc(stcb->sctp_ep, stcb, SCTP_NORMAL_PROC, SCTP_FROM_SCTP_INPUT + SCTP_LOC_3);
341 		}
342 		return (-1);
343 	}
344 	asoc = &stcb->asoc;
345 	/* process the peer's parameters in the INIT-ACK */
346 	retval = sctp_process_init((struct sctp_init_chunk *)cp, stcb, net);
347 	if (retval < 0) {
348 		return (retval);
349 	}
350 	initack_limit = offset + ntohs(cp->ch.chunk_length);
351 	/* load all addresses */
352 	if ((retval = sctp_load_addresses_from_init(stcb, m, iphlen,
353 	    (offset + sizeof(struct sctp_init_chunk)), initack_limit, sh,
354 	    NULL))) {
355 		/* Huh, we should abort */
356 #ifdef SCTP_DEBUG
357 		if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
358 			printf("Load addresses from INIT causes an abort %d\n", retval);
359 		}
360 #endif
361 		sctp_abort_association(stcb->sctp_ep, stcb, m, iphlen, sh,
362 		    NULL);
363 		return (-1);
364 	}
365 	stcb->asoc.peer_hmac_id = sctp_negotiate_hmacid(stcb->asoc.peer_hmacs,
366 	    stcb->asoc.local_hmacs);
367 	if (op_err) {
368 		sctp_queue_op_err(stcb, op_err);
369 		/* queuing will steal away the mbuf chain to the out queue */
370 		op_err = NULL;
371 	}
372 	/* extract the cookie and queue it to "echo" it back... */
373 	stcb->asoc.overall_error_count = 0;
374 	net->error_count = 0;
375 
376 	/*
377 	 * Cancel the INIT timer, We do this first before queueing the
378 	 * cookie. We always cancel at the primary to assue that we are
379 	 * canceling the timer started by the INIT which always goes to the
380 	 * primary.
381 	 */
382 	sctp_timer_stop(SCTP_TIMER_TYPE_INIT, stcb->sctp_ep, stcb,
383 	    asoc->primary_destination, SCTP_FROM_SCTP_INPUT + SCTP_LOC_4);
384 
385 	/* calculate the RTO */
386 	net->RTO = sctp_calculate_rto(stcb, asoc, net, &asoc->time_entered);
387 
388 	retval = sctp_send_cookie_echo(m, offset, stcb, net);
389 	if (retval < 0) {
390 		/*
391 		 * No cookie, we probably should send a op error. But in any
392 		 * case if there is no cookie in the INIT-ACK, we can
393 		 * abandon the peer, its broke.
394 		 */
395 		if (retval == -3) {
396 			/* We abort with an error of missing mandatory param */
397 			struct mbuf *op_err;
398 
399 			op_err =
400 			    sctp_generate_invmanparam(SCTP_CAUSE_MISSING_PARAM);
401 			if (op_err) {
402 				/*
403 				 * Expand beyond to include the mandatory
404 				 * param cookie
405 				 */
406 				struct sctp_inv_mandatory_param *mp;
407 
408 				SCTP_BUF_LEN(op_err) =
409 				    sizeof(struct sctp_inv_mandatory_param);
410 				mp = mtod(op_err,
411 				    struct sctp_inv_mandatory_param *);
412 				/* Subtract the reserved param */
413 				mp->length =
414 				    htons(sizeof(struct sctp_inv_mandatory_param) - 2);
415 				mp->num_param = htonl(1);
416 				mp->param = htons(SCTP_STATE_COOKIE);
417 				mp->resv = 0;
418 			}
419 			sctp_abort_association(stcb->sctp_ep, stcb, m, iphlen,
420 			    sh, op_err);
421 		}
422 		return (retval);
423 	}
424 	return (0);
425 }
426 
427 static void
428 sctp_handle_heartbeat_ack(struct sctp_heartbeat_chunk *cp,
429     struct sctp_tcb *stcb, struct sctp_nets *net)
430 {
431 	struct sockaddr_storage store;
432 	struct sockaddr_in *sin;
433 	struct sockaddr_in6 *sin6;
434 	struct sctp_nets *r_net;
435 	struct timeval tv;
436 
437 	if (ntohs(cp->ch.chunk_length) != sizeof(struct sctp_heartbeat_chunk)) {
438 		/* Invalid length */
439 		return;
440 	}
441 	sin = (struct sockaddr_in *)&store;
442 	sin6 = (struct sockaddr_in6 *)&store;
443 
444 	memset(&store, 0, sizeof(store));
445 	if (cp->heartbeat.hb_info.addr_family == AF_INET &&
446 	    cp->heartbeat.hb_info.addr_len == sizeof(struct sockaddr_in)) {
447 		sin->sin_family = cp->heartbeat.hb_info.addr_family;
448 		sin->sin_len = cp->heartbeat.hb_info.addr_len;
449 		sin->sin_port = stcb->rport;
450 		memcpy(&sin->sin_addr, cp->heartbeat.hb_info.address,
451 		    sizeof(sin->sin_addr));
452 	} else if (cp->heartbeat.hb_info.addr_family == AF_INET6 &&
453 	    cp->heartbeat.hb_info.addr_len == sizeof(struct sockaddr_in6)) {
454 		sin6->sin6_family = cp->heartbeat.hb_info.addr_family;
455 		sin6->sin6_len = cp->heartbeat.hb_info.addr_len;
456 		sin6->sin6_port = stcb->rport;
457 		memcpy(&sin6->sin6_addr, cp->heartbeat.hb_info.address,
458 		    sizeof(sin6->sin6_addr));
459 	} else {
460 		return;
461 	}
462 	r_net = sctp_findnet(stcb, (struct sockaddr *)sin);
463 	if (r_net == NULL) {
464 #ifdef SCTP_DEBUG
465 		if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
466 			printf("Huh? I can't find the address I sent it to, discard\n");
467 		}
468 #endif
469 		return;
470 	}
471 	if ((r_net && (r_net->dest_state & SCTP_ADDR_UNCONFIRMED)) &&
472 	    (r_net->heartbeat_random1 == cp->heartbeat.hb_info.random_value1) &&
473 	    (r_net->heartbeat_random2 == cp->heartbeat.hb_info.random_value2)) {
474 		/*
475 		 * If the its a HB and it's random value is correct when can
476 		 * confirm the destination.
477 		 */
478 		r_net->dest_state &= ~SCTP_ADDR_UNCONFIRMED;
479 		sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_CONFIRMED,
480 		    stcb, 0, (void *)r_net);
481 	}
482 	r_net->error_count = 0;
483 	r_net->hb_responded = 1;
484 	tv.tv_sec = cp->heartbeat.hb_info.time_value_1;
485 	tv.tv_usec = cp->heartbeat.hb_info.time_value_2;
486 	if (r_net->dest_state & SCTP_ADDR_NOT_REACHABLE) {
487 		r_net->dest_state &= ~SCTP_ADDR_NOT_REACHABLE;
488 		r_net->dest_state |= SCTP_ADDR_REACHABLE;
489 		sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_UP, stcb,
490 		    SCTP_HEARTBEAT_SUCCESS, (void *)r_net);
491 		/* now was it the primary? if so restore */
492 		if (r_net->dest_state & SCTP_ADDR_WAS_PRIMARY) {
493 			sctp_set_primary_addr(stcb, (struct sockaddr *)NULL, r_net);
494 		}
495 	}
496 	/* Now lets do a RTO with this */
497 	r_net->RTO = sctp_calculate_rto(stcb, &stcb->asoc, r_net, &tv);
498 }
499 
500 static void
501 sctp_handle_abort(struct sctp_abort_chunk *cp,
502     struct sctp_tcb *stcb, struct sctp_nets *net)
503 {
504 
505 #ifdef SCTP_DEBUG
506 	if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
507 		printf("sctp_handle_abort: handling ABORT\n");
508 	}
509 #endif
510 	if (stcb == NULL)
511 		return;
512 	/* verify that the destination addr is in the association */
513 	/* ignore abort for addresses being deleted */
514 
515 	/* stop any receive timers */
516 	sctp_timer_stop(SCTP_TIMER_TYPE_RECV, stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_5);
517 	/* notify user of the abort and clean up... */
518 	sctp_abort_notification(stcb, 0);
519 	/* free the tcb */
520 	SCTP_STAT_INCR_COUNTER32(sctps_aborted);
521 	if ((SCTP_GET_STATE(&stcb->asoc) == SCTP_STATE_OPEN) ||
522 	    (SCTP_GET_STATE(&stcb->asoc) == SCTP_STATE_SHUTDOWN_RECEIVED)) {
523 		SCTP_STAT_DECR_GAUGE32(sctps_currestab);
524 	}
525 	sctp_free_assoc(stcb->sctp_ep, stcb, SCTP_NORMAL_PROC, SCTP_FROM_SCTP_INPUT + SCTP_LOC_6);
526 #ifdef SCTP_DEBUG
527 	if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
528 		printf("sctp_handle_abort: finished\n");
529 	}
530 #endif
531 }
532 
533 static void
534 sctp_handle_shutdown(struct sctp_shutdown_chunk *cp,
535     struct sctp_tcb *stcb, struct sctp_nets *net, int *abort_flag)
536 {
537 	struct sctp_association *asoc;
538 	int some_on_streamwheel;
539 
540 #ifdef SCTP_DEBUG
541 	if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
542 		printf("sctp_handle_shutdown: handling SHUTDOWN\n");
543 	}
544 #endif
545 	if (stcb == NULL)
546 		return;
547 	asoc = &stcb->asoc;
548 	if ((SCTP_GET_STATE(asoc) == SCTP_STATE_COOKIE_WAIT) ||
549 	    (SCTP_GET_STATE(asoc) == SCTP_STATE_COOKIE_ECHOED)) {
550 		return;
551 	}
552 	if (ntohs(cp->ch.chunk_length) != sizeof(struct sctp_shutdown_chunk)) {
553 		/* Shutdown NOT the expected size */
554 		return;
555 	} else {
556 		sctp_update_acked(stcb, cp, net, abort_flag);
557 	}
558 	if (asoc->control_pdapi) {
559 		/*
560 		 * With a normal shutdown we assume the end of last record.
561 		 */
562 		SCTP_INP_READ_LOCK(stcb->sctp_ep);
563 		asoc->control_pdapi->end_added = 1;
564 		asoc->control_pdapi->pdapi_aborted = 1;
565 		asoc->control_pdapi = NULL;
566 		SCTP_INP_READ_UNLOCK(stcb->sctp_ep);
567 		sctp_sorwakeup(stcb->sctp_ep, stcb->sctp_socket);
568 	}
569 	/* goto SHUTDOWN_RECEIVED state to block new requests */
570 	if (stcb->sctp_socket) {
571 		if ((SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_RECEIVED) &&
572 		    (SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_SENT)) {
573 			asoc->state = SCTP_STATE_SHUTDOWN_RECEIVED;
574 			/*
575 			 * notify upper layer that peer has initiated a
576 			 * shutdown
577 			 */
578 			sctp_ulp_notify(SCTP_NOTIFY_PEER_SHUTDOWN, stcb, 0, NULL);
579 
580 			/* reset time */
581 			SCTP_GETTIME_TIMEVAL(&asoc->time_entered);
582 		}
583 	}
584 	if (SCTP_GET_STATE(asoc) == SCTP_STATE_SHUTDOWN_SENT) {
585 		/*
586 		 * stop the shutdown timer, since we WILL move to
587 		 * SHUTDOWN-ACK-SENT.
588 		 */
589 		sctp_timer_stop(SCTP_TIMER_TYPE_SHUTDOWN, stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_7);
590 	}
591 	/* Now are we there yet? */
592 	some_on_streamwheel = 0;
593 	if (!TAILQ_EMPTY(&asoc->out_wheel)) {
594 		/* Check to see if some data queued */
595 		struct sctp_stream_out *outs;
596 
597 		TAILQ_FOREACH(outs, &asoc->out_wheel, next_spoke) {
598 			if (!TAILQ_EMPTY(&outs->outqueue)) {
599 				some_on_streamwheel = 1;
600 				break;
601 			}
602 		}
603 	}
604 	if (!TAILQ_EMPTY(&asoc->send_queue) ||
605 	    !TAILQ_EMPTY(&asoc->sent_queue) ||
606 	    some_on_streamwheel) {
607 		/* By returning we will push more data out */
608 		return;
609 	} else {
610 		/* no outstanding data to send, so move on... */
611 		/* send SHUTDOWN-ACK */
612 		sctp_send_shutdown_ack(stcb, stcb->asoc.primary_destination);
613 		/* move to SHUTDOWN-ACK-SENT state */
614 		if ((SCTP_GET_STATE(asoc) == SCTP_STATE_OPEN) ||
615 		    (SCTP_GET_STATE(asoc) == SCTP_STATE_SHUTDOWN_RECEIVED)) {
616 			SCTP_STAT_DECR_GAUGE32(sctps_currestab);
617 		}
618 		asoc->state = SCTP_STATE_SHUTDOWN_ACK_SENT;
619 
620 		/* start SHUTDOWN timer */
621 		sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNACK, stcb->sctp_ep,
622 		    stcb, net);
623 	}
624 }
625 
626 static void
627 sctp_handle_shutdown_ack(struct sctp_shutdown_ack_chunk *cp,
628     struct sctp_tcb *stcb, struct sctp_nets *net)
629 {
630 	struct sctp_association *asoc;
631 
632 #ifdef SCTP_DEBUG
633 	if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
634 		printf("sctp_handle_shutdown_ack: handling SHUTDOWN ACK\n");
635 	}
636 #endif
637 	if (stcb == NULL)
638 		return;
639 
640 	asoc = &stcb->asoc;
641 	/* process according to association state */
642 	if ((SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_SENT) &&
643 	    (SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_ACK_SENT)) {
644 		/* unexpected SHUTDOWN-ACK... so ignore... */
645 		SCTP_TCB_UNLOCK(stcb);
646 		return;
647 	}
648 	if (asoc->control_pdapi) {
649 		/*
650 		 * With a normal shutdown we assume the end of last record.
651 		 */
652 		SCTP_INP_READ_LOCK(stcb->sctp_ep);
653 		asoc->control_pdapi->end_added = 1;
654 		asoc->control_pdapi->pdapi_aborted = 1;
655 		asoc->control_pdapi = NULL;
656 		SCTP_INP_READ_UNLOCK(stcb->sctp_ep);
657 		sctp_sorwakeup(stcb->sctp_ep, stcb->sctp_socket);
658 	}
659 	/* are the queues empty? */
660 	if (!TAILQ_EMPTY(&asoc->send_queue) ||
661 	    !TAILQ_EMPTY(&asoc->sent_queue) ||
662 	    !TAILQ_EMPTY(&asoc->out_wheel)) {
663 		sctp_report_all_outbound(stcb, 0);
664 	}
665 	/* stop the timer */
666 	sctp_timer_stop(SCTP_TIMER_TYPE_SHUTDOWN, stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_8);
667 	/* send SHUTDOWN-COMPLETE */
668 	sctp_send_shutdown_complete(stcb, net);
669 	/* notify upper layer protocol */
670 	if (stcb->sctp_socket) {
671 		sctp_ulp_notify(SCTP_NOTIFY_ASSOC_DOWN, stcb, 0, NULL);
672 		if ((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) ||
673 		    (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_IN_TCPPOOL)) {
674 			/* Set the connected flag to disconnected */
675 			stcb->sctp_ep->sctp_socket->so_snd.sb_cc = 0;
676 		}
677 	}
678 	SCTP_STAT_INCR_COUNTER32(sctps_shutdown);
679 	/* free the TCB but first save off the ep */
680 	sctp_free_assoc(stcb->sctp_ep, stcb, SCTP_NORMAL_PROC,
681 	    SCTP_FROM_SCTP_INPUT + SCTP_LOC_9);
682 }
683 
684 /*
685  * Skip past the param header and then we will find the chunk that caused the
686  * problem. There are two possiblities ASCONF or FWD-TSN other than that and
687  * our peer must be broken.
688  */
689 static void
690 sctp_process_unrecog_chunk(struct sctp_tcb *stcb, struct sctp_paramhdr *phdr,
691     struct sctp_nets *net)
692 {
693 	struct sctp_chunkhdr *chk;
694 
695 	chk = (struct sctp_chunkhdr *)((caddr_t)phdr + sizeof(*phdr));
696 	switch (chk->chunk_type) {
697 	case SCTP_ASCONF_ACK:
698 	case SCTP_ASCONF:
699 		sctp_asconf_cleanup(stcb, net);
700 		break;
701 	case SCTP_FORWARD_CUM_TSN:
702 		stcb->asoc.peer_supports_prsctp = 0;
703 		break;
704 	default:
705 #ifdef SCTP_DEBUG
706 		if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
707 			printf("Peer does not support chunk type %d(%x)??\n",
708 			    chk->chunk_type, (uint32_t) chk->chunk_type);
709 		}
710 #endif
711 		break;
712 	}
713 }
714 
715 /*
716  * Skip past the param header and then we will find the param that caused the
717  * problem.  There are a number of param's in a ASCONF OR the prsctp param
718  * these will turn of specific features.
719  */
720 static void
721 sctp_process_unrecog_param(struct sctp_tcb *stcb, struct sctp_paramhdr *phdr)
722 {
723 	struct sctp_paramhdr *pbad;
724 
725 	pbad = phdr + 1;
726 	switch (ntohs(pbad->param_type)) {
727 		/* pr-sctp draft */
728 	case SCTP_PRSCTP_SUPPORTED:
729 		stcb->asoc.peer_supports_prsctp = 0;
730 		break;
731 	case SCTP_SUPPORTED_CHUNK_EXT:
732 		break;
733 		/* draft-ietf-tsvwg-addip-sctp */
734 	case SCTP_ECN_NONCE_SUPPORTED:
735 		stcb->asoc.peer_supports_ecn_nonce = 0;
736 		stcb->asoc.ecn_nonce_allowed = 0;
737 		stcb->asoc.ecn_allowed = 0;
738 		break;
739 	case SCTP_ADD_IP_ADDRESS:
740 	case SCTP_DEL_IP_ADDRESS:
741 	case SCTP_SET_PRIM_ADDR:
742 		stcb->asoc.peer_supports_asconf = 0;
743 		break;
744 	case SCTP_SUCCESS_REPORT:
745 	case SCTP_ERROR_CAUSE_IND:
746 #ifdef SCTP_DEBUG
747 		if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
748 			printf("Huh, the peer does not support success? or error cause?\n");
749 			printf("Turning off ASCONF to this strange peer\n");
750 		}
751 #endif
752 		stcb->asoc.peer_supports_asconf = 0;
753 		break;
754 	default:
755 #ifdef SCTP_DEBUG
756 		if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
757 			printf("Peer does not support param type %d(%x)??\n",
758 			    pbad->param_type, (uint32_t) pbad->param_type);
759 		}
760 #endif
761 		break;
762 	}
763 }
764 
765 static int
766 sctp_handle_error(struct sctp_chunkhdr *ch,
767     struct sctp_tcb *stcb, struct sctp_nets *net)
768 {
769 	int chklen;
770 	struct sctp_paramhdr *phdr;
771 	uint16_t error_type;
772 	uint16_t error_len;
773 	struct sctp_association *asoc;
774 
775 	int adjust;
776 
777 	/* parse through all of the errors and process */
778 	asoc = &stcb->asoc;
779 	phdr = (struct sctp_paramhdr *)((caddr_t)ch +
780 	    sizeof(struct sctp_chunkhdr));
781 	chklen = ntohs(ch->chunk_length) - sizeof(struct sctp_chunkhdr);
782 	while ((size_t)chklen >= sizeof(struct sctp_paramhdr)) {
783 		/* Process an Error Cause */
784 		error_type = ntohs(phdr->param_type);
785 		error_len = ntohs(phdr->param_length);
786 		if ((error_len > chklen) || (error_len == 0)) {
787 			/* invalid param length for this param */
788 #ifdef SCTP_DEBUG
789 			if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
790 				printf("Bogus length in error param- chunk left:%d errorlen:%d\n",
791 				    chklen, error_len);
792 			}
793 #endif				/* SCTP_DEBUG */
794 			return (0);
795 		}
796 		switch (error_type) {
797 		case SCTP_CAUSE_INVALID_STREAM:
798 		case SCTP_CAUSE_MISSING_PARAM:
799 		case SCTP_CAUSE_INVALID_PARAM:
800 		case SCTP_CAUSE_NO_USER_DATA:
801 #ifdef SCTP_DEBUG
802 			if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
803 				printf("Software error we got a %d back? We have a bug :/ (or do they?)\n",
804 				    error_type);
805 			}
806 #endif
807 			break;
808 		case SCTP_CAUSE_STALE_COOKIE:
809 			/*
810 			 * We only act if we have echoed a cookie and are
811 			 * waiting.
812 			 */
813 			if (SCTP_GET_STATE(asoc) == SCTP_STATE_COOKIE_ECHOED) {
814 				int *p;
815 
816 				p = (int *)((caddr_t)phdr + sizeof(*phdr));
817 				/* Save the time doubled */
818 				asoc->cookie_preserve_req = ntohl(*p) << 1;
819 				asoc->stale_cookie_count++;
820 				if (asoc->stale_cookie_count >
821 				    asoc->max_init_times) {
822 					sctp_abort_notification(stcb, 0);
823 					/* now free the asoc */
824 					sctp_free_assoc(stcb->sctp_ep, stcb, SCTP_NORMAL_PROC, SCTP_FROM_SCTP_INPUT + SCTP_LOC_10);
825 					return (-1);
826 				}
827 				/* blast back to INIT state */
828 				asoc->state &= ~SCTP_STATE_COOKIE_ECHOED;
829 				asoc->state |= SCTP_STATE_COOKIE_WAIT;
830 
831 				sctp_stop_all_cookie_timers(stcb);
832 				sctp_send_initiate(stcb->sctp_ep, stcb);
833 			}
834 			break;
835 		case SCTP_CAUSE_UNRESOLVABLE_ADDR:
836 			/*
837 			 * Nothing we can do here, we don't do hostname
838 			 * addresses so if the peer does not like my IPv6
839 			 * (or IPv4 for that matter) it does not matter. If
840 			 * they don't support that type of address, they can
841 			 * NOT possibly get that packet type... i.e. with no
842 			 * IPv6 you can't recieve a IPv6 packet. so we can
843 			 * safely ignore this one. If we ever added support
844 			 * for HOSTNAME Addresses, then we would need to do
845 			 * something here.
846 			 */
847 			break;
848 		case SCTP_CAUSE_UNRECOG_CHUNK:
849 			sctp_process_unrecog_chunk(stcb, phdr, net);
850 			break;
851 		case SCTP_CAUSE_UNRECOG_PARAM:
852 			sctp_process_unrecog_param(stcb, phdr);
853 			break;
854 		case SCTP_CAUSE_COOKIE_IN_SHUTDOWN:
855 			/*
856 			 * We ignore this since the timer will drive out a
857 			 * new cookie anyway and there timer will drive us
858 			 * to send a SHUTDOWN_COMPLETE. We can't send one
859 			 * here since we don't have their tag.
860 			 */
861 			break;
862 		case SCTP_CAUSE_DELETING_LAST_ADDR:
863 		case SCTP_CAUSE_RESOURCE_SHORTAGE:
864 		case SCTP_CAUSE_DELETING_SRC_ADDR:
865 			/*
866 			 * We should NOT get these here, but in a
867 			 * ASCONF-ACK.
868 			 */
869 #ifdef SCTP_DEBUG
870 			if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
871 				printf("Peer sends ASCONF errors in a Operational Error?<%d>?\n",
872 				    error_type);
873 			}
874 #endif
875 			break;
876 		case SCTP_CAUSE_OUT_OF_RESC:
877 			/*
878 			 * And what, pray tell do we do with the fact that
879 			 * the peer is out of resources? Not really sure we
880 			 * could do anything but abort. I suspect this
881 			 * should have came WITH an abort instead of in a
882 			 * OP-ERROR.
883 			 */
884 			break;
885 		default:
886 #ifdef SCTP_DEBUG
887 			if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
888 				/* don't know what this error cause is... */
889 				printf("sctp_handle_error: unknown error type = 0x%xh\n",
890 				    error_type);
891 			}
892 #endif				/* SCTP_DEBUG */
893 			break;
894 		}
895 		adjust = SCTP_SIZE32(error_len);
896 		chklen -= adjust;
897 		phdr = (struct sctp_paramhdr *)((caddr_t)phdr + adjust);
898 	}
899 	return (0);
900 }
901 
902 static int
903 sctp_handle_init_ack(struct mbuf *m, int iphlen, int offset, struct sctphdr *sh,
904     struct sctp_init_ack_chunk *cp, struct sctp_tcb *stcb,
905     struct sctp_nets *net)
906 {
907 	struct sctp_init_ack *init_ack;
908 	int *state;
909 	struct mbuf *op_err;
910 
911 #ifdef SCTP_DEBUG
912 	if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
913 		printf("sctp_handle_init_ack: handling INIT-ACK\n");
914 	}
915 #endif
916 	if (stcb == NULL) {
917 #ifdef SCTP_DEBUG
918 		if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
919 			printf("sctp_handle_init_ack: TCB is null\n");
920 		}
921 #endif
922 		return (-1);
923 	}
924 	if (ntohs(cp->ch.chunk_length) < sizeof(struct sctp_init_ack_chunk)) {
925 		/* Invalid length */
926 		op_err = sctp_generate_invmanparam(SCTP_CAUSE_INVALID_PARAM);
927 		sctp_abort_association(stcb->sctp_ep, stcb, m, iphlen, sh,
928 		    op_err);
929 		return (-1);
930 	}
931 	init_ack = &cp->init;
932 	/* validate parameters */
933 	if (init_ack->initiate_tag == 0) {
934 		/* protocol error... send an abort */
935 		op_err = sctp_generate_invmanparam(SCTP_CAUSE_INVALID_PARAM);
936 		sctp_abort_association(stcb->sctp_ep, stcb, m, iphlen, sh,
937 		    op_err);
938 		return (-1);
939 	}
940 	if (ntohl(init_ack->a_rwnd) < SCTP_MIN_RWND) {
941 		/* protocol error... send an abort */
942 		op_err = sctp_generate_invmanparam(SCTP_CAUSE_INVALID_PARAM);
943 		sctp_abort_association(stcb->sctp_ep, stcb, m, iphlen, sh,
944 		    op_err);
945 		return (-1);
946 	}
947 	if (init_ack->num_inbound_streams == 0) {
948 		/* protocol error... send an abort */
949 		op_err = sctp_generate_invmanparam(SCTP_CAUSE_INVALID_PARAM);
950 		sctp_abort_association(stcb->sctp_ep, stcb, m, iphlen, sh,
951 		    op_err);
952 		return (-1);
953 	}
954 	if (init_ack->num_outbound_streams == 0) {
955 		/* protocol error... send an abort */
956 		op_err = sctp_generate_invmanparam(SCTP_CAUSE_INVALID_PARAM);
957 		sctp_abort_association(stcb->sctp_ep, stcb, m, iphlen, sh,
958 		    op_err);
959 		return (-1);
960 	}
961 	/* process according to association state... */
962 	state = &stcb->asoc.state;
963 	switch (*state & SCTP_STATE_MASK) {
964 	case SCTP_STATE_COOKIE_WAIT:
965 		/* this is the expected state for this chunk */
966 		/* process the INIT-ACK parameters */
967 		if (stcb->asoc.primary_destination->dest_state &
968 		    SCTP_ADDR_UNCONFIRMED) {
969 			/*
970 			 * The primary is where we sent the INIT, we can
971 			 * always consider it confirmed when the INIT-ACK is
972 			 * returned. Do this before we load addresses
973 			 * though.
974 			 */
975 			stcb->asoc.primary_destination->dest_state &=
976 			    ~SCTP_ADDR_UNCONFIRMED;
977 			sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_CONFIRMED,
978 			    stcb, 0, (void *)stcb->asoc.primary_destination);
979 		}
980 		if (sctp_process_init_ack(m, iphlen, offset, sh, cp, stcb, net
981 		    ) < 0) {
982 			/* error in parsing parameters */
983 			return (-1);
984 		}
985 		/* update our state */
986 #ifdef SCTP_DEBUG
987 		if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
988 			printf("moving to COOKIE-ECHOED state\n");
989 		}
990 #endif
991 		if (*state & SCTP_STATE_SHUTDOWN_PENDING) {
992 			*state = SCTP_STATE_COOKIE_ECHOED |
993 			    SCTP_STATE_SHUTDOWN_PENDING;
994 		} else {
995 			*state = SCTP_STATE_COOKIE_ECHOED;
996 		}
997 
998 		/* reset the RTO calc */
999 		stcb->asoc.overall_error_count = 0;
1000 		SCTP_GETTIME_TIMEVAL(&stcb->asoc.time_entered);
1001 		/*
1002 		 * collapse the init timer back in case of a exponential
1003 		 * backoff
1004 		 */
1005 		sctp_timer_start(SCTP_TIMER_TYPE_COOKIE, stcb->sctp_ep,
1006 		    stcb, net);
1007 		/*
1008 		 * the send at the end of the inbound data processing will
1009 		 * cause the cookie to be sent
1010 		 */
1011 		break;
1012 	case SCTP_STATE_SHUTDOWN_SENT:
1013 		/* incorrect state... discard */
1014 		break;
1015 	case SCTP_STATE_COOKIE_ECHOED:
1016 		/* incorrect state... discard */
1017 		break;
1018 	case SCTP_STATE_OPEN:
1019 		/* incorrect state... discard */
1020 		break;
1021 	case SCTP_STATE_EMPTY:
1022 	case SCTP_STATE_INUSE:
1023 	default:
1024 		/* incorrect state... discard */
1025 		return (-1);
1026 		break;
1027 	}			/* end switch asoc state */
1028 #ifdef SCTP_DEBUG
1029 	if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
1030 		printf("Leaving handle-init-ack end\n");
1031 	}
1032 #endif
1033 	return (0);
1034 }
1035 
1036 
1037 /*
1038  * handle a state cookie for an existing association m: input packet mbuf
1039  * chain-- assumes a pullup on IP/SCTP/COOKIE-ECHO chunk note: this is a
1040  * "split" mbuf and the cookie signature does not exist offset: offset into
1041  * mbuf to the cookie-echo chunk
1042  */
1043 static struct sctp_tcb *
1044 sctp_process_cookie_existing(struct mbuf *m, int iphlen, int offset,
1045     struct sctphdr *sh, struct sctp_state_cookie *cookie, int cookie_len,
1046     struct sctp_inpcb *inp, struct sctp_tcb *stcb, struct sctp_nets *net,
1047     struct sockaddr *init_src, int *notification, sctp_assoc_t * sac_assoc_id)
1048 {
1049 	struct sctp_association *asoc;
1050 	struct sctp_init_chunk *init_cp, init_buf;
1051 	struct sctp_init_ack_chunk *initack_cp, initack_buf;
1052 	int chk_length;
1053 	int init_offset, initack_offset, i;
1054 	int retval;
1055 	int spec_flag = 0;
1056 	int how_indx;
1057 
1058 	/* I know that the TCB is non-NULL from the caller */
1059 	asoc = &stcb->asoc;
1060 	for (how_indx = 0; how_indx < sizeof(asoc->cookie_how); how_indx++) {
1061 		if (asoc->cookie_how[how_indx] == 0)
1062 			break;
1063 	}
1064 	if (how_indx < sizeof(asoc->cookie_how)) {
1065 		asoc->cookie_how[how_indx] = 1;
1066 	}
1067 	if (SCTP_GET_STATE(asoc) == SCTP_STATE_SHUTDOWN_ACK_SENT) {
1068 		/* SHUTDOWN came in after sending INIT-ACK */
1069 		struct mbuf *op_err;
1070 		struct sctp_paramhdr *ph;
1071 
1072 		sctp_send_shutdown_ack(stcb, stcb->asoc.primary_destination);
1073 		op_err = sctp_get_mbuf_for_msg(sizeof(struct sctp_paramhdr),
1074 		    0, M_DONTWAIT, 1, MT_DATA);
1075 		if (op_err == NULL) {
1076 			/* FOOBAR */
1077 			return (NULL);
1078 		}
1079 		/* pre-reserve some space */
1080 		SCTP_BUF_RESV_UF(op_err, sizeof(struct ip6_hdr));
1081 		SCTP_BUF_RESV_UF(op_err, sizeof(struct sctphdr));
1082 		SCTP_BUF_RESV_UF(op_err, sizeof(struct sctp_chunkhdr));
1083 		/* Set the len */
1084 		SCTP_BUF_LEN(op_err) = sizeof(struct sctp_paramhdr);
1085 		ph = mtod(op_err, struct sctp_paramhdr *);
1086 		ph->param_type = htons(SCTP_CAUSE_COOKIE_IN_SHUTDOWN);
1087 		ph->param_length = htons(sizeof(struct sctp_paramhdr));
1088 		sctp_send_operr_to(m, iphlen, op_err, cookie->peers_vtag);
1089 		if (how_indx < sizeof(asoc->cookie_how))
1090 			asoc->cookie_how[how_indx] = 2;
1091 		return (NULL);
1092 	}
1093 	/*
1094 	 * find and validate the INIT chunk in the cookie (peer's info) the
1095 	 * INIT should start after the cookie-echo header struct (chunk
1096 	 * header, state cookie header struct)
1097 	 */
1098 	init_offset = offset += sizeof(struct sctp_cookie_echo_chunk);
1099 
1100 	init_cp = (struct sctp_init_chunk *)
1101 	    sctp_m_getptr(m, init_offset, sizeof(struct sctp_init_chunk),
1102 	    (uint8_t *) & init_buf);
1103 	if (init_cp == NULL) {
1104 		/* could not pull a INIT chunk in cookie */
1105 		return (NULL);
1106 	}
1107 	chk_length = ntohs(init_cp->ch.chunk_length);
1108 	if (init_cp->ch.chunk_type != SCTP_INITIATION) {
1109 		return (NULL);
1110 	}
1111 	/*
1112 	 * find and validate the INIT-ACK chunk in the cookie (my info) the
1113 	 * INIT-ACK follows the INIT chunk
1114 	 */
1115 	initack_offset = init_offset + SCTP_SIZE32(chk_length);
1116 	initack_cp = (struct sctp_init_ack_chunk *)
1117 	    sctp_m_getptr(m, initack_offset, sizeof(struct sctp_init_ack_chunk),
1118 	    (uint8_t *) & initack_buf);
1119 	if (initack_cp == NULL) {
1120 		/* could not pull INIT-ACK chunk in cookie */
1121 		return (NULL);
1122 	}
1123 	chk_length = ntohs(initack_cp->ch.chunk_length);
1124 	if (initack_cp->ch.chunk_type != SCTP_INITIATION_ACK) {
1125 		return (NULL);
1126 	}
1127 	if ((ntohl(initack_cp->init.initiate_tag) == asoc->my_vtag) &&
1128 	    (ntohl(init_cp->init.initiate_tag) == asoc->peer_vtag)) {
1129 		/*
1130 		 * case D in Section 5.2.4 Table 2: MMAA process accordingly
1131 		 * to get into the OPEN state
1132 		 */
1133 		if (ntohl(initack_cp->init.initial_tsn) != asoc->init_seq_number) {
1134 #ifdef INVARIANTS
1135 			panic("Case D and non-match seq?");
1136 #else
1137 			printf("Case D, seq non-match %x vs %x?\n",
1138 			    ntohl(initack_cp->init.initial_tsn), asoc->init_seq_number);
1139 #endif
1140 		}
1141 		switch SCTP_GET_STATE
1142 			(asoc) {
1143 		case SCTP_STATE_COOKIE_WAIT:
1144 		case SCTP_STATE_COOKIE_ECHOED:
1145 			/*
1146 			 * INIT was sent, but got got a COOKIE_ECHO with the
1147 			 * correct tags... just accept it...but we must
1148 			 * process the init so that we can make sure we have
1149 			 * the right seq no's.
1150 			 */
1151 			/* First we must process the INIT !! */
1152 			retval = sctp_process_init(init_cp, stcb, net);
1153 			if (retval < 0) {
1154 				if (how_indx < sizeof(asoc->cookie_how))
1155 					asoc->cookie_how[how_indx] = 3;
1156 				return (NULL);
1157 			}
1158 			/* we have already processed the INIT so no problem */
1159 			sctp_timer_stop(SCTP_TIMER_TYPE_HEARTBEAT, inp, stcb,
1160 			    net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_11);
1161 			sctp_timer_stop(SCTP_TIMER_TYPE_INIT, inp, stcb, net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_12);
1162 			/* update current state */
1163 			if (SCTP_GET_STATE(asoc) == SCTP_STATE_COOKIE_ECHOED)
1164 				SCTP_STAT_INCR_COUNTER32(sctps_activeestab);
1165 			else
1166 				SCTP_STAT_INCR_COUNTER32(sctps_collisionestab);
1167 			if (asoc->state & SCTP_STATE_SHUTDOWN_PENDING) {
1168 				asoc->state = SCTP_STATE_OPEN | SCTP_STATE_SHUTDOWN_PENDING;
1169 				sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
1170 				    stcb->sctp_ep, stcb, asoc->primary_destination);
1171 
1172 			} else {
1173 				/* if ok, move to OPEN state */
1174 				asoc->state = SCTP_STATE_OPEN;
1175 			}
1176 			SCTP_STAT_INCR_GAUGE32(sctps_currestab);
1177 			sctp_stop_all_cookie_timers(stcb);
1178 			if (((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) ||
1179 			    (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_IN_TCPPOOL)) &&
1180 			    (inp->sctp_socket->so_qlimit == 0)
1181 			    ) {
1182 				/*
1183 				 * Here is where collision would go if we
1184 				 * did a connect() and instead got a
1185 				 * init/init-ack/cookie done before the
1186 				 * init-ack came back..
1187 				 */
1188 				stcb->sctp_ep->sctp_flags |=
1189 				    SCTP_PCB_FLAGS_CONNECTED;
1190 				soisconnected(stcb->sctp_ep->sctp_socket);
1191 			}
1192 			/* notify upper layer */
1193 			*notification = SCTP_NOTIFY_ASSOC_UP;
1194 			/*
1195 			 * since we did not send a HB make sure we don't
1196 			 * double things
1197 			 */
1198 			net->hb_responded = 1;
1199 
1200 			if (stcb->asoc.sctp_autoclose_ticks &&
1201 			    (sctp_is_feature_on(inp, SCTP_PCB_FLAGS_AUTOCLOSE))) {
1202 				sctp_timer_start(SCTP_TIMER_TYPE_AUTOCLOSE,
1203 				    inp, stcb, NULL);
1204 			}
1205 			break;
1206 		default:
1207 			/*
1208 			 * we're in the OPEN state (or beyond), so peer must
1209 			 * have simply lost the COOKIE-ACK
1210 			 */
1211 
1212 			break;
1213 			}	/* end switch */
1214 		sctp_stop_all_cookie_timers(stcb);
1215 		/*
1216 		 * We ignore the return code here.. not sure if we should
1217 		 * somehow abort.. but we do have an existing asoc. This
1218 		 * really should not fail.
1219 		 */
1220 		if (sctp_load_addresses_from_init(stcb, m, iphlen,
1221 		    init_offset + sizeof(struct sctp_init_chunk),
1222 		    initack_offset, sh, init_src)) {
1223 			if (how_indx < sizeof(asoc->cookie_how))
1224 				asoc->cookie_how[how_indx] = 4;
1225 			return (NULL);
1226 		}
1227 		/* respond with a COOKIE-ACK */
1228 		sctp_toss_old_cookies(stcb, asoc);
1229 		sctp_send_cookie_ack(stcb);
1230 		if (how_indx < sizeof(asoc->cookie_how))
1231 			asoc->cookie_how[how_indx] = 5;
1232 		return (stcb);
1233 	}			/* end if */
1234 	if (ntohl(initack_cp->init.initiate_tag) != asoc->my_vtag &&
1235 	    ntohl(init_cp->init.initiate_tag) == asoc->peer_vtag &&
1236 	    cookie->tie_tag_my_vtag == 0 &&
1237 	    cookie->tie_tag_peer_vtag == 0) {
1238 		/*
1239 		 * case C in Section 5.2.4 Table 2: XMOO silently discard
1240 		 */
1241 		if (how_indx < sizeof(asoc->cookie_how))
1242 			asoc->cookie_how[how_indx] = 6;
1243 		return (NULL);
1244 	}
1245 	if (ntohl(initack_cp->init.initiate_tag) == asoc->my_vtag &&
1246 	    (ntohl(init_cp->init.initiate_tag) != asoc->peer_vtag ||
1247 	    init_cp->init.initiate_tag == 0)) {
1248 		/*
1249 		 * case B in Section 5.2.4 Table 2: MXAA or MOAA my info
1250 		 * should be ok, re-accept peer info
1251 		 */
1252 		if (ntohl(initack_cp->init.initial_tsn) != asoc->init_seq_number) {
1253 			/*
1254 			 * Extension of case C. If we hit this, then the
1255 			 * random number generator returned the same vtag
1256 			 * when we first sent our INIT-ACK and when we later
1257 			 * sent our INIT. The side with the seq numbers that
1258 			 * are different will be the one that normnally
1259 			 * would have hit case C. This in effect "extends"
1260 			 * our vtags in this collision case to be 64 bits.
1261 			 * The same collision could occur aka you get both
1262 			 * vtag and seq number the same twice in a row.. but
1263 			 * is much less likely. If it did happen then we
1264 			 * would proceed through and bring up the assoc.. we
1265 			 * may end up with the wrong stream setup however..
1266 			 * which would be bad.. but there is no way to
1267 			 * tell.. until we send on a stream that does not
1268 			 * exist :-)
1269 			 */
1270 			if (how_indx < sizeof(asoc->cookie_how))
1271 				asoc->cookie_how[how_indx] = 7;
1272 
1273 			return (NULL);
1274 		}
1275 		if (how_indx < sizeof(asoc->cookie_how))
1276 			asoc->cookie_how[how_indx] = 8;
1277 		sctp_timer_stop(SCTP_TIMER_TYPE_HEARTBEAT, inp, stcb, net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_13);
1278 		sctp_stop_all_cookie_timers(stcb);
1279 		/*
1280 		 * since we did not send a HB make sure we don't double
1281 		 * things
1282 		 */
1283 		net->hb_responded = 1;
1284 		if (stcb->asoc.sctp_autoclose_ticks &&
1285 		    sctp_is_feature_on(inp, SCTP_PCB_FLAGS_AUTOCLOSE)) {
1286 			sctp_timer_start(SCTP_TIMER_TYPE_AUTOCLOSE, inp, stcb,
1287 			    NULL);
1288 		}
1289 		asoc->my_rwnd = ntohl(initack_cp->init.a_rwnd);
1290 		asoc->pre_open_streams = ntohs(initack_cp->init.num_outbound_streams);
1291 
1292 		/* Note last_cwr_tsn? where is this used? */
1293 		asoc->last_cwr_tsn = asoc->init_seq_number - 1;
1294 		if (ntohl(init_cp->init.initiate_tag) != asoc->peer_vtag) {
1295 			/*
1296 			 * Ok the peer probably discarded our data (if we
1297 			 * echoed a cookie+data). So anything on the
1298 			 * sent_queue should be marked for retransmit, we
1299 			 * may not get something to kick us so it COULD
1300 			 * still take a timeout to move these.. but it can't
1301 			 * hurt to mark them.
1302 			 */
1303 			struct sctp_tmit_chunk *chk;
1304 
1305 			TAILQ_FOREACH(chk, &stcb->asoc.sent_queue, sctp_next) {
1306 				if (chk->sent < SCTP_DATAGRAM_RESEND) {
1307 					chk->sent = SCTP_DATAGRAM_RESEND;
1308 					stcb->asoc.sent_queue_retran_cnt++;
1309 					spec_flag++;
1310 				}
1311 			}
1312 
1313 		}
1314 		/* process the INIT info (peer's info) */
1315 		retval = sctp_process_init(init_cp, stcb, net);
1316 		if (retval < 0) {
1317 			if (how_indx < sizeof(asoc->cookie_how))
1318 				asoc->cookie_how[how_indx] = 9;
1319 			return (NULL);
1320 		}
1321 		if (sctp_load_addresses_from_init(stcb, m, iphlen,
1322 		    init_offset + sizeof(struct sctp_init_chunk),
1323 		    initack_offset, sh, init_src)) {
1324 			if (how_indx < sizeof(asoc->cookie_how))
1325 				asoc->cookie_how[how_indx] = 10;
1326 			return (NULL);
1327 		}
1328 		if ((asoc->state & SCTP_STATE_COOKIE_WAIT) ||
1329 		    (asoc->state & SCTP_STATE_COOKIE_ECHOED)) {
1330 			*notification = SCTP_NOTIFY_ASSOC_UP;
1331 
1332 			if (((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) ||
1333 			    (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_IN_TCPPOOL)) &&
1334 			    (inp->sctp_socket->so_qlimit == 0)) {
1335 				stcb->sctp_ep->sctp_flags |=
1336 				    SCTP_PCB_FLAGS_CONNECTED;
1337 				soisconnected(stcb->sctp_ep->sctp_socket);
1338 			}
1339 			if (SCTP_GET_STATE(asoc) == SCTP_STATE_COOKIE_ECHOED)
1340 				SCTP_STAT_INCR_COUNTER32(sctps_activeestab);
1341 			else
1342 				SCTP_STAT_INCR_COUNTER32(sctps_collisionestab);
1343 			SCTP_STAT_INCR_COUNTER32(sctps_activeestab);
1344 			SCTP_STAT_INCR_GAUGE32(sctps_currestab);
1345 		} else if (SCTP_GET_STATE(asoc) == SCTP_STATE_OPEN) {
1346 			SCTP_STAT_INCR_COUNTER32(sctps_restartestab);
1347 		} else {
1348 			SCTP_STAT_INCR_COUNTER32(sctps_collisionestab);
1349 		}
1350 		if (asoc->state & SCTP_STATE_SHUTDOWN_PENDING) {
1351 			asoc->state = SCTP_STATE_OPEN | SCTP_STATE_SHUTDOWN_PENDING;
1352 			sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
1353 			    stcb->sctp_ep, stcb, asoc->primary_destination);
1354 
1355 		} else {
1356 			asoc->state = SCTP_STATE_OPEN;
1357 		}
1358 		sctp_stop_all_cookie_timers(stcb);
1359 		sctp_toss_old_cookies(stcb, asoc);
1360 		sctp_send_cookie_ack(stcb);
1361 		if (spec_flag) {
1362 			/*
1363 			 * only if we have retrans set do we do this. What
1364 			 * this call does is get only the COOKIE-ACK out and
1365 			 * then when we return the normal call to
1366 			 * sctp_chunk_output will get the retrans out behind
1367 			 * this.
1368 			 */
1369 			sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_COOKIE_ACK);
1370 		}
1371 		if (how_indx < sizeof(asoc->cookie_how))
1372 			asoc->cookie_how[how_indx] = 11;
1373 
1374 		return (stcb);
1375 	}
1376 	if ((ntohl(initack_cp->init.initiate_tag) != asoc->my_vtag &&
1377 	    ntohl(init_cp->init.initiate_tag) != asoc->peer_vtag) &&
1378 	    cookie->tie_tag_my_vtag == asoc->my_vtag_nonce &&
1379 	    cookie->tie_tag_peer_vtag == asoc->peer_vtag_nonce &&
1380 	    cookie->tie_tag_peer_vtag != 0) {
1381 		struct sctpasochead *head;
1382 
1383 		/*
1384 		 * case A in Section 5.2.4 Table 2: XXMM (peer restarted)
1385 		 */
1386 		/* temp code */
1387 		if (how_indx < sizeof(asoc->cookie_how))
1388 			asoc->cookie_how[how_indx] = 12;
1389 		sctp_timer_stop(SCTP_TIMER_TYPE_INIT, inp, stcb, net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_14);
1390 		sctp_timer_stop(SCTP_TIMER_TYPE_HEARTBEAT, inp, stcb, net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_15);
1391 
1392 		*sac_assoc_id = sctp_get_associd(stcb);
1393 		/* notify upper layer */
1394 		*notification = SCTP_NOTIFY_ASSOC_RESTART;
1395 		atomic_add_int(&stcb->asoc.refcnt, 1);
1396 		if ((SCTP_GET_STATE(asoc) != SCTP_STATE_OPEN) &&
1397 		    (SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_RECEIVED) &&
1398 		    (SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_SENT)) {
1399 			SCTP_STAT_INCR_GAUGE32(sctps_currestab);
1400 		}
1401 		if (SCTP_GET_STATE(asoc) == SCTP_STATE_OPEN) {
1402 			SCTP_STAT_INCR_GAUGE32(sctps_restartestab);
1403 		} else if (SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_SENT) {
1404 			SCTP_STAT_INCR_GAUGE32(sctps_collisionestab);
1405 		}
1406 		if (asoc->state & SCTP_STATE_SHUTDOWN_PENDING) {
1407 			asoc->state = SCTP_STATE_OPEN |
1408 			    SCTP_STATE_SHUTDOWN_PENDING;
1409 			sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
1410 			    stcb->sctp_ep, stcb, asoc->primary_destination);
1411 
1412 		} else if (!(asoc->state & SCTP_STATE_SHUTDOWN_SENT)) {
1413 			/* move to OPEN state, if not in SHUTDOWN_SENT */
1414 			asoc->state = SCTP_STATE_OPEN;
1415 		}
1416 		asoc->pre_open_streams =
1417 		    ntohs(initack_cp->init.num_outbound_streams);
1418 		asoc->init_seq_number = ntohl(initack_cp->init.initial_tsn);
1419 		asoc->sending_seq = asoc->asconf_seq_out = asoc->str_reset_seq_out = asoc->init_seq_number;
1420 
1421 		asoc->last_cwr_tsn = asoc->init_seq_number - 1;
1422 		asoc->asconf_seq_in = asoc->last_acked_seq = asoc->init_seq_number - 1;
1423 
1424 		asoc->str_reset_seq_in = asoc->init_seq_number;
1425 
1426 		asoc->advanced_peer_ack_point = asoc->last_acked_seq;
1427 		if (asoc->mapping_array)
1428 			memset(asoc->mapping_array, 0,
1429 			    asoc->mapping_array_size);
1430 		SCTP_TCB_UNLOCK(stcb);
1431 		SCTP_INP_INFO_WLOCK();
1432 		SCTP_INP_WLOCK(stcb->sctp_ep);
1433 		SCTP_TCB_LOCK(stcb);
1434 		atomic_add_int(&stcb->asoc.refcnt, -1);
1435 		/* send up all the data */
1436 		SCTP_TCB_SEND_LOCK(stcb);
1437 
1438 		sctp_report_all_outbound(stcb, 1);
1439 		for (i = 0; i < stcb->asoc.streamoutcnt; i++) {
1440 			stcb->asoc.strmout[i].stream_no = i;
1441 			stcb->asoc.strmout[i].next_sequence_sent = 0;
1442 			stcb->asoc.strmout[i].last_msg_incomplete = 0;
1443 		}
1444 		/* process the INIT-ACK info (my info) */
1445 		asoc->my_vtag = ntohl(initack_cp->init.initiate_tag);
1446 		asoc->my_rwnd = ntohl(initack_cp->init.a_rwnd);
1447 
1448 		/* pull from vtag hash */
1449 		LIST_REMOVE(stcb, sctp_asocs);
1450 		/* re-insert to new vtag position */
1451 		head = &sctppcbinfo.sctp_asochash[SCTP_PCBHASH_ASOC(stcb->asoc.my_vtag,
1452 		    sctppcbinfo.hashasocmark)];
1453 		/*
1454 		 * put it in the bucket in the vtag hash of assoc's for the
1455 		 * system
1456 		 */
1457 		LIST_INSERT_HEAD(head, stcb, sctp_asocs);
1458 
1459 		/* Is this the first restart? */
1460 		if (stcb->asoc.in_restart_hash == 0) {
1461 			/* Ok add it to assoc_id vtag hash */
1462 			head = &sctppcbinfo.sctp_restarthash[SCTP_PCBHASH_ASOC(stcb->asoc.assoc_id,
1463 			    sctppcbinfo.hashrestartmark)];
1464 			LIST_INSERT_HEAD(head, stcb, sctp_tcbrestarhash);
1465 			stcb->asoc.in_restart_hash = 1;
1466 		}
1467 		/* process the INIT info (peer's info) */
1468 		SCTP_TCB_SEND_UNLOCK(stcb);
1469 		SCTP_INP_WUNLOCK(stcb->sctp_ep);
1470 		SCTP_INP_INFO_WUNLOCK();
1471 
1472 		retval = sctp_process_init(init_cp, stcb, net);
1473 		if (retval < 0) {
1474 			if (how_indx < sizeof(asoc->cookie_how))
1475 				asoc->cookie_how[how_indx] = 13;
1476 
1477 			return (NULL);
1478 		}
1479 		/*
1480 		 * since we did not send a HB make sure we don't double
1481 		 * things
1482 		 */
1483 		net->hb_responded = 1;
1484 
1485 		if (sctp_load_addresses_from_init(stcb, m, iphlen,
1486 		    init_offset + sizeof(struct sctp_init_chunk),
1487 		    initack_offset, sh, init_src)) {
1488 			if (how_indx < sizeof(asoc->cookie_how))
1489 				asoc->cookie_how[how_indx] = 14;
1490 
1491 			return (NULL);
1492 		}
1493 		/* respond with a COOKIE-ACK */
1494 		sctp_stop_all_cookie_timers(stcb);
1495 		sctp_toss_old_cookies(stcb, asoc);
1496 		sctp_send_cookie_ack(stcb);
1497 		if (how_indx < sizeof(asoc->cookie_how))
1498 			asoc->cookie_how[how_indx] = 15;
1499 
1500 		return (stcb);
1501 	}
1502 	if (how_indx < sizeof(asoc->cookie_how))
1503 		asoc->cookie_how[how_indx] = 16;
1504 	/* all other cases... */
1505 	return (NULL);
1506 }
1507 
1508 
1509 /*
1510  * handle a state cookie for a new association m: input packet mbuf chain--
1511  * assumes a pullup on IP/SCTP/COOKIE-ECHO chunk note: this is a "split" mbuf
1512  * and the cookie signature does not exist offset: offset into mbuf to the
1513  * cookie-echo chunk length: length of the cookie chunk to: where the init
1514  * was from returns a new TCB
1515  */
1516 static struct sctp_tcb *
1517 sctp_process_cookie_new(struct mbuf *m, int iphlen, int offset,
1518     struct sctphdr *sh, struct sctp_state_cookie *cookie, int cookie_len,
1519     struct sctp_inpcb *inp, struct sctp_nets **netp,
1520     struct sockaddr *init_src, int *notification,
1521     int auth_skipped, uint32_t auth_offset, uint32_t auth_len)
1522 {
1523 	struct sctp_tcb *stcb;
1524 	struct sctp_init_chunk *init_cp, init_buf;
1525 	struct sctp_init_ack_chunk *initack_cp, initack_buf;
1526 	struct sockaddr_storage sa_store;
1527 	struct sockaddr *initack_src = (struct sockaddr *)&sa_store;
1528 	struct sockaddr_in *sin;
1529 	struct sockaddr_in6 *sin6;
1530 	struct sctp_association *asoc;
1531 	int chk_length;
1532 	int init_offset, initack_offset, initack_limit;
1533 	int retval;
1534 	int error = 0;
1535 	uint32_t old_tag;
1536 	uint8_t auth_chunk_buf[SCTP_PARAM_BUFFER_SIZE];
1537 
1538 	/*
1539 	 * find and validate the INIT chunk in the cookie (peer's info) the
1540 	 * INIT should start after the cookie-echo header struct (chunk
1541 	 * header, state cookie header struct)
1542 	 */
1543 	init_offset = offset + sizeof(struct sctp_cookie_echo_chunk);
1544 	init_cp = (struct sctp_init_chunk *)
1545 	    sctp_m_getptr(m, init_offset, sizeof(struct sctp_init_chunk),
1546 	    (uint8_t *) & init_buf);
1547 	if (init_cp == NULL) {
1548 		/* could not pull a INIT chunk in cookie */
1549 #ifdef SCTP_DEBUG
1550 		if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
1551 			printf("process_cookie_new: could not pull INIT chunk hdr\n");
1552 		}
1553 #endif				/* SCTP_DEBUG */
1554 		return (NULL);
1555 	}
1556 	chk_length = ntohs(init_cp->ch.chunk_length);
1557 	if (init_cp->ch.chunk_type != SCTP_INITIATION) {
1558 #ifdef SCTP_DEBUG
1559 		if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
1560 			printf("HUH? process_cookie_new: could not find INIT chunk!\n");
1561 		}
1562 #endif				/* SCTP_DEBUG */
1563 		return (NULL);
1564 	}
1565 	initack_offset = init_offset + SCTP_SIZE32(chk_length);
1566 	/*
1567 	 * find and validate the INIT-ACK chunk in the cookie (my info) the
1568 	 * INIT-ACK follows the INIT chunk
1569 	 */
1570 	initack_cp = (struct sctp_init_ack_chunk *)
1571 	    sctp_m_getptr(m, initack_offset, sizeof(struct sctp_init_ack_chunk),
1572 	    (uint8_t *) & initack_buf);
1573 	if (initack_cp == NULL) {
1574 		/* could not pull INIT-ACK chunk in cookie */
1575 #ifdef SCTP_DEBUG
1576 		if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
1577 			printf("process_cookie_new: could not pull INIT-ACK chunk hdr\n");
1578 		}
1579 #endif				/* SCTP_DEBUG */
1580 		return (NULL);
1581 	}
1582 	chk_length = ntohs(initack_cp->ch.chunk_length);
1583 	if (initack_cp->ch.chunk_type != SCTP_INITIATION_ACK) {
1584 		return (NULL);
1585 	}
1586 	/*
1587 	 * NOTE: We can't use the INIT_ACK's chk_length to determine the
1588 	 * "initack_limit" value.  This is because the chk_length field
1589 	 * includes the length of the cookie, but the cookie is omitted when
1590 	 * the INIT and INIT_ACK are tacked onto the cookie...
1591 	 */
1592 	initack_limit = offset + cookie_len;
1593 
1594 	/*
1595 	 * now that we know the INIT/INIT-ACK are in place, create a new TCB
1596 	 * and popluate
1597 	 */
1598 	stcb = sctp_aloc_assoc(inp, init_src, 0, &error,
1599 	    ntohl(initack_cp->init.initiate_tag));
1600 	if (stcb == NULL) {
1601 		struct mbuf *op_err;
1602 
1603 		/* memory problem? */
1604 #ifdef SCTP_DEBUG
1605 		if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
1606 			printf("process_cookie_new: no room for another TCB!\n");
1607 		}
1608 #endif				/* SCTP_DEBUG */
1609 		op_err = sctp_generate_invmanparam(SCTP_CAUSE_OUT_OF_RESC);
1610 		sctp_abort_association(inp, (struct sctp_tcb *)NULL, m, iphlen,
1611 		    sh, op_err);
1612 		return (NULL);
1613 	}
1614 	/* get the correct sctp_nets */
1615 	*netp = sctp_findnet(stcb, init_src);
1616 	asoc = &stcb->asoc;
1617 	/* get scope variables out of cookie */
1618 	asoc->ipv4_local_scope = cookie->ipv4_scope;
1619 	asoc->site_scope = cookie->site_scope;
1620 	asoc->local_scope = cookie->local_scope;
1621 	asoc->loopback_scope = cookie->loopback_scope;
1622 
1623 	if ((asoc->ipv4_addr_legal != cookie->ipv4_addr_legal) ||
1624 	    (asoc->ipv6_addr_legal != cookie->ipv6_addr_legal)) {
1625 		struct mbuf *op_err;
1626 
1627 		/*
1628 		 * Houston we have a problem. The EP changed while the
1629 		 * cookie was in flight. Only recourse is to abort the
1630 		 * association.
1631 		 */
1632 		op_err = sctp_generate_invmanparam(SCTP_CAUSE_OUT_OF_RESC);
1633 		sctp_abort_association(inp, (struct sctp_tcb *)NULL, m, iphlen,
1634 		    sh, op_err);
1635 		return (NULL);
1636 	}
1637 	/* process the INIT-ACK info (my info) */
1638 	old_tag = asoc->my_vtag;
1639 	asoc->assoc_id = asoc->my_vtag = ntohl(initack_cp->init.initiate_tag);
1640 	asoc->my_rwnd = ntohl(initack_cp->init.a_rwnd);
1641 	asoc->pre_open_streams = ntohs(initack_cp->init.num_outbound_streams);
1642 	asoc->init_seq_number = ntohl(initack_cp->init.initial_tsn);
1643 	asoc->sending_seq = asoc->asconf_seq_out = asoc->str_reset_seq_out = asoc->init_seq_number;
1644 	asoc->last_cwr_tsn = asoc->init_seq_number - 1;
1645 	asoc->asconf_seq_in = asoc->last_acked_seq = asoc->init_seq_number - 1;
1646 	asoc->str_reset_seq_in = asoc->init_seq_number;
1647 
1648 	asoc->advanced_peer_ack_point = asoc->last_acked_seq;
1649 
1650 	/* process the INIT info (peer's info) */
1651 	retval = sctp_process_init(init_cp, stcb, *netp);
1652 	if (retval < 0) {
1653 		sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC, SCTP_FROM_SCTP_INPUT + SCTP_LOC_16);
1654 		return (NULL);
1655 	}
1656 	/* load all addresses */
1657 	if (sctp_load_addresses_from_init(stcb, m, iphlen,
1658 	    init_offset + sizeof(struct sctp_init_chunk), initack_offset, sh,
1659 	    init_src)) {
1660 		sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC, SCTP_FROM_SCTP_INPUT + SCTP_LOC_17);
1661 		return (NULL);
1662 	}
1663 	/*
1664 	 * verify any preceding AUTH chunk that was skipped
1665 	 */
1666 	/* pull the local authentication parameters from the cookie/init-ack */
1667 	sctp_auth_get_cookie_params(stcb, m,
1668 	    initack_offset + sizeof(struct sctp_init_ack_chunk),
1669 	    initack_limit - (initack_offset + sizeof(struct sctp_init_ack_chunk)));
1670 	if (auth_skipped) {
1671 		struct sctp_auth_chunk *auth;
1672 
1673 		auth = (struct sctp_auth_chunk *)
1674 		    sctp_m_getptr(m, auth_offset, auth_len, auth_chunk_buf);
1675 		if (sctp_handle_auth(stcb, auth, m, auth_offset)) {
1676 			/* auth HMAC failed, dump the assoc and packet */
1677 #ifdef SCTP_DEBUG
1678 			if (sctp_debug_on & SCTP_DEBUG_AUTH1)
1679 				printf("COOKIE-ECHO: AUTH failed\n");
1680 #endif				/* SCTP_DEBUG */
1681 			sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC, SCTP_FROM_SCTP_INPUT + SCTP_LOC_18);
1682 			return (NULL);
1683 		} else {
1684 			/* remaining chunks checked... good to go */
1685 			stcb->asoc.authenticated = 1;
1686 		}
1687 	}
1688 	/* update current state */
1689 #ifdef SCTP_DEBUG
1690 	if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
1691 		printf("moving to OPEN state\n");
1692 	}
1693 #endif
1694 	if (asoc->state & SCTP_STATE_SHUTDOWN_PENDING) {
1695 		asoc->state = SCTP_STATE_OPEN | SCTP_STATE_SHUTDOWN_PENDING;
1696 		sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
1697 		    stcb->sctp_ep, stcb, asoc->primary_destination);
1698 	} else {
1699 		asoc->state = SCTP_STATE_OPEN;
1700 	}
1701 	sctp_stop_all_cookie_timers(stcb);
1702 	SCTP_STAT_INCR_COUNTER32(sctps_passiveestab);
1703 	SCTP_STAT_INCR_GAUGE32(sctps_currestab);
1704 
1705 	/*
1706 	 * if we're doing ASCONFs, check to see if we have any new local
1707 	 * addresses that need to get added to the peer (eg. addresses
1708 	 * changed while cookie echo in flight).  This needs to be done
1709 	 * after we go to the OPEN state to do the correct asconf
1710 	 * processing. else, make sure we have the correct addresses in our
1711 	 * lists
1712 	 */
1713 
1714 	/* warning, we re-use sin, sin6, sa_store here! */
1715 	/* pull in local_address (our "from" address) */
1716 	if (cookie->laddr_type == SCTP_IPV4_ADDRESS) {
1717 		/* source addr is IPv4 */
1718 		sin = (struct sockaddr_in *)initack_src;
1719 		memset(sin, 0, sizeof(*sin));
1720 		sin->sin_family = AF_INET;
1721 		sin->sin_len = sizeof(struct sockaddr_in);
1722 		sin->sin_addr.s_addr = cookie->laddress[0];
1723 	} else if (cookie->laddr_type == SCTP_IPV6_ADDRESS) {
1724 		/* source addr is IPv6 */
1725 		sin6 = (struct sockaddr_in6 *)initack_src;
1726 		memset(sin6, 0, sizeof(*sin6));
1727 		sin6->sin6_family = AF_INET6;
1728 		sin6->sin6_len = sizeof(struct sockaddr_in6);
1729 		sin6->sin6_scope_id = cookie->scope_id;
1730 		memcpy(&sin6->sin6_addr, cookie->laddress,
1731 		    sizeof(sin6->sin6_addr));
1732 	} else {
1733 		sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC, SCTP_FROM_SCTP_INPUT + SCTP_LOC_19);
1734 		return (NULL);
1735 	}
1736 
1737 	sctp_check_address_list(stcb, m,
1738 	    initack_offset + sizeof(struct sctp_init_ack_chunk),
1739 	    initack_limit - (initack_offset + sizeof(struct sctp_init_ack_chunk)),
1740 	    initack_src, cookie->local_scope, cookie->site_scope,
1741 	    cookie->ipv4_scope, cookie->loopback_scope);
1742 
1743 
1744 	/* set up to notify upper layer */
1745 	*notification = SCTP_NOTIFY_ASSOC_UP;
1746 	if (((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) ||
1747 	    (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_IN_TCPPOOL)) &&
1748 	    (inp->sctp_socket->so_qlimit == 0)) {
1749 		/*
1750 		 * This is an endpoint that called connect() how it got a
1751 		 * cookie that is NEW is a bit of a mystery. It must be that
1752 		 * the INIT was sent, but before it got there.. a complete
1753 		 * INIT/INIT-ACK/COOKIE arrived. But of course then it
1754 		 * should have went to the other code.. not here.. oh well..
1755 		 * a bit of protection is worth having..
1756 		 */
1757 		stcb->sctp_ep->sctp_flags |= SCTP_PCB_FLAGS_CONNECTED;
1758 		soisconnected(stcb->sctp_ep->sctp_socket);
1759 	} else if ((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) &&
1760 	    (inp->sctp_socket->so_qlimit)) {
1761 		/*
1762 		 * We don't want to do anything with this one. Since it is
1763 		 * the listening guy. The timer will get started for
1764 		 * accepted connections in the caller.
1765 		 */
1766 		;
1767 	}
1768 	/* since we did not send a HB make sure we don't double things */
1769 	(*netp)->hb_responded = 1;
1770 
1771 	if (stcb->asoc.sctp_autoclose_ticks &&
1772 	    sctp_is_feature_on(inp, SCTP_PCB_FLAGS_AUTOCLOSE)) {
1773 		sctp_timer_start(SCTP_TIMER_TYPE_AUTOCLOSE, inp, stcb, NULL);
1774 	}
1775 	/* respond with a COOKIE-ACK */
1776 	/* calculate the RTT */
1777 	(*netp)->RTO = sctp_calculate_rto(stcb, asoc, *netp,
1778 	    &cookie->time_entered);
1779 	sctp_send_cookie_ack(stcb);
1780 	return (stcb);
1781 }
1782 
1783 
1784 /*
1785  * handles a COOKIE-ECHO message stcb: modified to either a new or left as
1786  * existing (non-NULL) TCB
1787  */
1788 static struct mbuf *
1789 sctp_handle_cookie_echo(struct mbuf *m, int iphlen, int offset,
1790     struct sctphdr *sh, struct sctp_cookie_echo_chunk *cp,
1791     struct sctp_inpcb **inp_p, struct sctp_tcb **stcb, struct sctp_nets **netp,
1792     int auth_skipped, uint32_t auth_offset, uint32_t auth_len, struct sctp_tcb **locked_tcb)
1793 {
1794 	struct sctp_state_cookie *cookie;
1795 	struct sockaddr_in6 sin6;
1796 	struct sockaddr_in sin;
1797 	struct sctp_tcb *l_stcb = *stcb;
1798 	struct sctp_inpcb *l_inp;
1799 	struct sockaddr *to;
1800 	sctp_assoc_t sac_restart_id;
1801 	struct sctp_pcb *ep;
1802 	struct mbuf *m_sig;
1803 	uint8_t calc_sig[SCTP_SIGNATURE_SIZE], tmp_sig[SCTP_SIGNATURE_SIZE];
1804 	uint8_t *sig;
1805 	uint8_t cookie_ok = 0;
1806 	unsigned int size_of_pkt, sig_offset, cookie_offset;
1807 	unsigned int cookie_len;
1808 	struct timeval now;
1809 	struct timeval time_expires;
1810 	struct sockaddr_storage dest_store;
1811 	struct sockaddr *localep_sa = (struct sockaddr *)&dest_store;
1812 	struct ip *iph;
1813 	int notification = 0;
1814 	struct sctp_nets *netl;
1815 	int had_a_existing_tcb = 0;
1816 
1817 #ifdef SCTP_DEBUG
1818 	if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
1819 		printf("sctp_handle_cookie: handling COOKIE-ECHO\n");
1820 	}
1821 #endif
1822 
1823 	if (inp_p == NULL) {
1824 		return (NULL);
1825 	}
1826 	/* First get the destination address setup too. */
1827 	iph = mtod(m, struct ip *);
1828 	if (iph->ip_v == IPVERSION) {
1829 		/* its IPv4 */
1830 		struct sockaddr_in *sin;
1831 
1832 		sin = (struct sockaddr_in *)(localep_sa);
1833 		memset(sin, 0, sizeof(*sin));
1834 		sin->sin_family = AF_INET;
1835 		sin->sin_len = sizeof(*sin);
1836 		sin->sin_port = sh->dest_port;
1837 		sin->sin_addr.s_addr = iph->ip_dst.s_addr;
1838 		size_of_pkt = SCTP_GET_IPV4_LENGTH(iph);
1839 	} else if (iph->ip_v == (IPV6_VERSION >> 4)) {
1840 		/* its IPv6 */
1841 		struct ip6_hdr *ip6;
1842 		struct sockaddr_in6 *sin6;
1843 
1844 		sin6 = (struct sockaddr_in6 *)(localep_sa);
1845 		memset(sin6, 0, sizeof(*sin6));
1846 		sin6->sin6_family = AF_INET6;
1847 		sin6->sin6_len = sizeof(struct sockaddr_in6);
1848 		ip6 = mtod(m, struct ip6_hdr *);
1849 		sin6->sin6_port = sh->dest_port;
1850 		sin6->sin6_addr = ip6->ip6_dst;
1851 		size_of_pkt = SCTP_GET_IPV6_LENGTH(ip6) + iphlen;
1852 	} else {
1853 		return (NULL);
1854 	}
1855 
1856 	cookie = &cp->cookie;
1857 	cookie_offset = offset + sizeof(struct sctp_chunkhdr);
1858 	cookie_len = ntohs(cp->ch.chunk_length);
1859 
1860 	if ((cookie->peerport != sh->src_port) &&
1861 	    (cookie->myport != sh->dest_port) &&
1862 	    (cookie->my_vtag != sh->v_tag)) {
1863 		/*
1864 		 * invalid ports or bad tag.  Note that we always leave the
1865 		 * v_tag in the header in network order and when we stored
1866 		 * it in the my_vtag slot we also left it in network order.
1867 		 * This maintians the match even though it may be in the
1868 		 * opposite byte order of the machine :->
1869 		 */
1870 		return (NULL);
1871 	}
1872 	if (cookie_len > size_of_pkt ||
1873 	    cookie_len < sizeof(struct sctp_cookie_echo_chunk) +
1874 	    sizeof(struct sctp_init_chunk) +
1875 	    sizeof(struct sctp_init_ack_chunk) + SCTP_SIGNATURE_SIZE) {
1876 		/* cookie too long!  or too small */
1877 		return (NULL);
1878 	}
1879 	/*
1880 	 * split off the signature into its own mbuf (since it should not be
1881 	 * calculated in the sctp_hmac_m() call).
1882 	 */
1883 	sig_offset = offset + cookie_len - SCTP_SIGNATURE_SIZE;
1884 	if (sig_offset > size_of_pkt) {
1885 		/* packet not correct size! */
1886 		/* XXX this may already be accounted for earlier... */
1887 		return (NULL);
1888 	}
1889 	m_sig = m_split(m, sig_offset, M_DONTWAIT);
1890 	if (m_sig == NULL) {
1891 		/* out of memory or ?? */
1892 		return (NULL);
1893 	}
1894 	/*
1895 	 * compute the signature/digest for the cookie
1896 	 */
1897 	ep = &(*inp_p)->sctp_ep;
1898 	l_inp = *inp_p;
1899 	if (l_stcb) {
1900 		SCTP_TCB_UNLOCK(l_stcb);
1901 	}
1902 	SCTP_INP_RLOCK(l_inp);
1903 	if (l_stcb) {
1904 		SCTP_TCB_LOCK(l_stcb);
1905 	}
1906 	/* which cookie is it? */
1907 	if ((cookie->time_entered.tv_sec < (long)ep->time_of_secret_change) &&
1908 	    (ep->current_secret_number != ep->last_secret_number)) {
1909 		/* it's the old cookie */
1910 		sctp_hmac_m(SCTP_HMAC,
1911 		    (uint8_t *) ep->secret_key[(int)ep->last_secret_number],
1912 		    SCTP_SECRET_SIZE, m, cookie_offset, calc_sig);
1913 	} else {
1914 		/* it's the current cookie */
1915 		sctp_hmac_m(SCTP_HMAC,
1916 		    (uint8_t *) ep->secret_key[(int)ep->current_secret_number],
1917 		    SCTP_SECRET_SIZE, m, cookie_offset, calc_sig);
1918 	}
1919 	/* get the signature */
1920 	SCTP_INP_RUNLOCK(l_inp);
1921 	sig = (uint8_t *) sctp_m_getptr(m_sig, 0, SCTP_SIGNATURE_SIZE, (uint8_t *) & tmp_sig);
1922 	if (sig == NULL) {
1923 		/* couldn't find signature */
1924 		sctp_m_freem(m_sig);
1925 		return (NULL);
1926 	}
1927 	/* compare the received digest with the computed digest */
1928 	if (memcmp(calc_sig, sig, SCTP_SIGNATURE_SIZE) != 0) {
1929 		/* try the old cookie? */
1930 		if ((cookie->time_entered.tv_sec == (long)ep->time_of_secret_change) &&
1931 		    (ep->current_secret_number != ep->last_secret_number)) {
1932 			/* compute digest with old */
1933 			sctp_hmac_m(SCTP_HMAC,
1934 			    (uint8_t *) ep->secret_key[(int)ep->last_secret_number],
1935 			    SCTP_SECRET_SIZE, m, cookie_offset, calc_sig);
1936 			/* compare */
1937 			if (memcmp(calc_sig, sig, SCTP_SIGNATURE_SIZE) == 0)
1938 				cookie_ok = 1;
1939 		}
1940 	} else {
1941 		cookie_ok = 1;
1942 	}
1943 
1944 	/*
1945 	 * Now before we continue we must reconstruct our mbuf so that
1946 	 * normal processing of any other chunks will work.
1947 	 */
1948 	{
1949 		struct mbuf *m_at;
1950 
1951 		m_at = m;
1952 		while (SCTP_BUF_NEXT(m_at) != NULL) {
1953 			m_at = SCTP_BUF_NEXT(m_at);
1954 		}
1955 		SCTP_BUF_NEXT(m_at) = m_sig;
1956 	}
1957 
1958 	if (cookie_ok == 0) {
1959 #ifdef SCTP_DEBUG
1960 		if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
1961 			printf("handle_cookie_echo: cookie signature validation failed!\n");
1962 			printf("offset = %u, cookie_offset = %u, sig_offset = %u\n",
1963 			    (uint32_t) offset, cookie_offset, sig_offset);
1964 		}
1965 #endif
1966 		return (NULL);
1967 	}
1968 	/*
1969 	 * check the cookie timestamps to be sure it's not stale
1970 	 */
1971 	SCTP_GETTIME_TIMEVAL(&now);
1972 	/* Expire time is in Ticks, so we convert to seconds */
1973 	time_expires.tv_sec = cookie->time_entered.tv_sec + cookie->cookie_life;
1974 	time_expires.tv_usec = cookie->time_entered.tv_usec;
1975 	if (timevalcmp(&now, &time_expires, >)) {
1976 		/* cookie is stale! */
1977 		struct mbuf *op_err;
1978 		struct sctp_stale_cookie_msg *scm;
1979 		uint32_t tim;
1980 
1981 		op_err = sctp_get_mbuf_for_msg(sizeof(struct sctp_stale_cookie_msg),
1982 		    0, M_DONTWAIT, 1, MT_DATA);
1983 		if (op_err == NULL) {
1984 			/* FOOBAR */
1985 			return (NULL);
1986 		}
1987 		/* pre-reserve some space */
1988 		SCTP_BUF_RESV_UF(op_err, sizeof(struct ip6_hdr));
1989 		SCTP_BUF_RESV_UF(op_err, sizeof(struct sctphdr));
1990 		SCTP_BUF_RESV_UF(op_err, sizeof(struct sctp_chunkhdr));
1991 
1992 		/* Set the len */
1993 		SCTP_BUF_LEN(op_err) = sizeof(struct sctp_stale_cookie_msg);
1994 		scm = mtod(op_err, struct sctp_stale_cookie_msg *);
1995 		scm->ph.param_type = htons(SCTP_CAUSE_STALE_COOKIE);
1996 		scm->ph.param_length = htons((sizeof(struct sctp_paramhdr) +
1997 		    (sizeof(uint32_t))));
1998 		/* seconds to usec */
1999 		tim = (now.tv_sec - time_expires.tv_sec) * 1000000;
2000 		/* add in usec */
2001 		if (tim == 0)
2002 			tim = now.tv_usec - cookie->time_entered.tv_usec;
2003 		scm->time_usec = htonl(tim);
2004 		sctp_send_operr_to(m, iphlen, op_err, cookie->peers_vtag);
2005 		return (NULL);
2006 	}
2007 	/*
2008 	 * Now we must see with the lookup address if we have an existing
2009 	 * asoc. This will only happen if we were in the COOKIE-WAIT state
2010 	 * and a INIT collided with us and somewhere the peer sent the
2011 	 * cookie on another address besides the single address our assoc
2012 	 * had for him. In this case we will have one of the tie-tags set at
2013 	 * least AND the address field in the cookie can be used to look it
2014 	 * up.
2015 	 */
2016 	to = NULL;
2017 	if (cookie->addr_type == SCTP_IPV6_ADDRESS) {
2018 		memset(&sin6, 0, sizeof(sin6));
2019 		sin6.sin6_family = AF_INET6;
2020 		sin6.sin6_len = sizeof(sin6);
2021 		sin6.sin6_port = sh->src_port;
2022 		sin6.sin6_scope_id = cookie->scope_id;
2023 		memcpy(&sin6.sin6_addr.s6_addr, cookie->address,
2024 		    sizeof(sin6.sin6_addr.s6_addr));
2025 		to = (struct sockaddr *)&sin6;
2026 	} else if (cookie->addr_type == SCTP_IPV4_ADDRESS) {
2027 		memset(&sin, 0, sizeof(sin));
2028 		sin.sin_family = AF_INET;
2029 		sin.sin_len = sizeof(sin);
2030 		sin.sin_port = sh->src_port;
2031 		sin.sin_addr.s_addr = cookie->address[0];
2032 		to = (struct sockaddr *)&sin;
2033 	}
2034 	if ((*stcb == NULL) && to) {
2035 		/* Yep, lets check */
2036 		*stcb = sctp_findassociation_ep_addr(inp_p, to, netp, localep_sa, NULL);
2037 		if (*stcb == NULL) {
2038 			/*
2039 			 * We should have only got back the same inp. If we
2040 			 * got back a different ep we have a problem. The
2041 			 * original findep got back l_inp and now
2042 			 */
2043 			if (l_inp != *inp_p) {
2044 				printf("Bad problem find_ep got a diff inp then special_locate?\n");
2045 			}
2046 		} else {
2047 			if (*locked_tcb == NULL) {
2048 				/*
2049 				 * In this case we found the assoc only
2050 				 * after we locked the create lock. This
2051 				 * means we are in a colliding case and we
2052 				 * must make sure that we unlock the tcb if
2053 				 * its one of the cases where we throw away
2054 				 * the incoming packets.
2055 				 */
2056 				*locked_tcb = *stcb;
2057 
2058 				/*
2059 				 * We must also increment the inp ref count
2060 				 * since the ref_count flags was set when we
2061 				 * did not find the TCB, now we found it
2062 				 * which reduces the refcount.. we must
2063 				 * raise it back out to balance it all :-)
2064 				 */
2065 				SCTP_INP_INCR_REF((*stcb)->sctp_ep);
2066 				if ((*stcb)->sctp_ep != l_inp) {
2067 					printf("Huh? ep:%p diff then l_inp:%p?\n",
2068 					    (*stcb)->sctp_ep, l_inp);
2069 				}
2070 			}
2071 		}
2072 	}
2073 	cookie_len -= SCTP_SIGNATURE_SIZE;
2074 	if (*stcb == NULL) {
2075 		/* this is the "normal" case... get a new TCB */
2076 		*stcb = sctp_process_cookie_new(m, iphlen, offset, sh, cookie,
2077 		    cookie_len, *inp_p, netp, to, &notification,
2078 		    auth_skipped, auth_offset, auth_len);
2079 	} else {
2080 		/* this is abnormal... cookie-echo on existing TCB */
2081 		had_a_existing_tcb = 1;
2082 		*stcb = sctp_process_cookie_existing(m, iphlen, offset, sh,
2083 		    cookie, cookie_len, *inp_p, *stcb, *netp, to, &notification,
2084 		    &sac_restart_id);
2085 	}
2086 
2087 	if (*stcb == NULL) {
2088 		/* still no TCB... must be bad cookie-echo */
2089 		return (NULL);
2090 	}
2091 	/*
2092 	 * Ok, we built an association so confirm the address we sent the
2093 	 * INIT-ACK to.
2094 	 */
2095 	netl = sctp_findnet(*stcb, to);
2096 	/*
2097 	 * This code should in theory NOT run but
2098 	 */
2099 	if (netl == NULL) {
2100 		/* TSNH! Huh, why do I need to add this address here? */
2101 		int ret;
2102 
2103 		ret = sctp_add_remote_addr(*stcb, to, SCTP_DONOT_SETSCOPE,
2104 		    SCTP_IN_COOKIE_PROC);
2105 		netl = sctp_findnet(*stcb, to);
2106 	}
2107 	if (netl) {
2108 		if (netl->dest_state & SCTP_ADDR_UNCONFIRMED) {
2109 			netl->dest_state &= ~SCTP_ADDR_UNCONFIRMED;
2110 			sctp_set_primary_addr((*stcb), (struct sockaddr *)NULL,
2111 			    netl);
2112 			sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_CONFIRMED,
2113 			    (*stcb), 0, (void *)netl);
2114 		}
2115 	}
2116 	if (*stcb) {
2117 		sctp_timer_start(SCTP_TIMER_TYPE_HEARTBEAT, *inp_p,
2118 		    *stcb, NULL);
2119 	}
2120 	if ((*inp_p)->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) {
2121 		if (!had_a_existing_tcb ||
2122 		    (((*inp_p)->sctp_flags & SCTP_PCB_FLAGS_CONNECTED) == 0)) {
2123 			/*
2124 			 * If we have a NEW cookie or the connect never
2125 			 * reached the connected state during collision we
2126 			 * must do the TCP accept thing.
2127 			 */
2128 			struct socket *so, *oso;
2129 			struct sctp_inpcb *inp;
2130 
2131 			if (notification == SCTP_NOTIFY_ASSOC_RESTART) {
2132 				/*
2133 				 * For a restart we will keep the same
2134 				 * socket, no need to do anything. I THINK!!
2135 				 */
2136 				sctp_ulp_notify(notification, *stcb, 0, (void *)&sac_restart_id);
2137 				return (m);
2138 			}
2139 			oso = (*inp_p)->sctp_socket;
2140 			/*
2141 			 * We do this to keep the sockets side happy durin
2142 			 * the sonewcon ONLY.
2143 			 */
2144 			NET_LOCK_GIANT();
2145 			SCTP_TCB_UNLOCK((*stcb));
2146 			so = sonewconn(oso, 0
2147 			    );
2148 			NET_UNLOCK_GIANT();
2149 			SCTP_INP_WLOCK((*stcb)->sctp_ep);
2150 			SCTP_TCB_LOCK((*stcb));
2151 			SCTP_INP_WUNLOCK((*stcb)->sctp_ep);
2152 			if (so == NULL) {
2153 				struct mbuf *op_err;
2154 
2155 				/* Too many sockets */
2156 #ifdef SCTP_DEBUG
2157 				if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
2158 					printf("process_cookie_new: no room for another socket!\n");
2159 				}
2160 #endif				/* SCTP_DEBUG */
2161 				op_err = sctp_generate_invmanparam(SCTP_CAUSE_OUT_OF_RESC);
2162 				sctp_abort_association(*inp_p, NULL, m, iphlen,
2163 				    sh, op_err);
2164 				sctp_free_assoc(*inp_p, *stcb, SCTP_NORMAL_PROC, SCTP_FROM_SCTP_INPUT + SCTP_LOC_20);
2165 				return (NULL);
2166 			}
2167 			inp = (struct sctp_inpcb *)so->so_pcb;
2168 			SCTP_INP_INCR_REF(inp);
2169 			/*
2170 			 * We add the unbound flag here so that if we get an
2171 			 * soabort() before we get the move_pcb done, we
2172 			 * will properly cleanup.
2173 			 */
2174 			inp->sctp_flags = (SCTP_PCB_FLAGS_TCPTYPE |
2175 			    SCTP_PCB_FLAGS_CONNECTED |
2176 			    SCTP_PCB_FLAGS_IN_TCPPOOL |
2177 			    SCTP_PCB_FLAGS_UNBOUND |
2178 			    (SCTP_PCB_COPY_FLAGS & (*inp_p)->sctp_flags) |
2179 			    SCTP_PCB_FLAGS_DONT_WAKE);
2180 			inp->sctp_features = (*inp_p)->sctp_features;
2181 			inp->sctp_socket = so;
2182 			inp->sctp_frag_point = (*inp_p)->sctp_frag_point;
2183 			inp->partial_delivery_point = (*inp_p)->partial_delivery_point;
2184 			inp->sctp_context = (*inp_p)->sctp_context;
2185 			inp->inp_starting_point_for_iterator = NULL;
2186 			/*
2187 			 * copy in the authentication parameters from the
2188 			 * original endpoint
2189 			 */
2190 			if (inp->sctp_ep.local_hmacs)
2191 				sctp_free_hmaclist(inp->sctp_ep.local_hmacs);
2192 			inp->sctp_ep.local_hmacs =
2193 			    sctp_copy_hmaclist((*inp_p)->sctp_ep.local_hmacs);
2194 			if (inp->sctp_ep.local_auth_chunks)
2195 				sctp_free_chunklist(inp->sctp_ep.local_auth_chunks);
2196 			inp->sctp_ep.local_auth_chunks =
2197 			    sctp_copy_chunklist((*inp_p)->sctp_ep.local_auth_chunks);
2198 			(void)sctp_copy_skeylist(&(*inp_p)->sctp_ep.shared_keys,
2199 			    &inp->sctp_ep.shared_keys);
2200 
2201 			/*
2202 			 * Now we must move it from one hash table to
2203 			 * another and get the tcb in the right place.
2204 			 */
2205 			sctp_move_pcb_and_assoc(*inp_p, inp, *stcb);
2206 			sctp_pull_off_control_to_new_inp((*inp_p), inp, *stcb);
2207 
2208 			/*
2209 			 * now we must check to see if we were aborted while
2210 			 * the move was going on and the lock/unlock
2211 			 * happened.
2212 			 */
2213 			if (inp->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) {
2214 				/*
2215 				 * yep it was, we leave the assoc attached
2216 				 * to the socket since the sctp_inpcb_free()
2217 				 * call will send an abort for us.
2218 				 */
2219 				SCTP_INP_DECR_REF(inp);
2220 				return (NULL);
2221 			}
2222 			SCTP_INP_DECR_REF(inp);
2223 			/* Switch over to the new guy */
2224 			*inp_p = inp;
2225 			sctp_ulp_notify(notification, *stcb, 0, NULL);
2226 
2227 			/*
2228 			 * Pull it from the incomplete queue and wake the
2229 			 * guy
2230 			 */
2231 			soisconnected(so);
2232 			return (m);
2233 		}
2234 	}
2235 	if ((notification) && ((*inp_p)->sctp_flags & SCTP_PCB_FLAGS_UDPTYPE)) {
2236 		sctp_ulp_notify(notification, *stcb, 0, NULL);
2237 	}
2238 	return (m);
2239 }
2240 
2241 static void
2242 sctp_handle_cookie_ack(struct sctp_cookie_ack_chunk *cp,
2243     struct sctp_tcb *stcb, struct sctp_nets *net)
2244 {
2245 	/* cp must not be used, others call this without a c-ack :-) */
2246 	struct sctp_association *asoc;
2247 
2248 #ifdef SCTP_DEBUG
2249 	if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
2250 		printf("sctp_handle_cookie_ack: handling COOKIE-ACK\n");
2251 	}
2252 #endif
2253 	if (stcb == NULL)
2254 		return;
2255 
2256 	asoc = &stcb->asoc;
2257 
2258 	sctp_stop_all_cookie_timers(stcb);
2259 	/* process according to association state */
2260 	if (SCTP_GET_STATE(asoc) == SCTP_STATE_COOKIE_ECHOED) {
2261 		/* state change only needed when I am in right state */
2262 #ifdef SCTP_DEBUG
2263 		if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
2264 			printf("moving to OPEN state\n");
2265 		}
2266 #endif
2267 		if (asoc->state & SCTP_STATE_SHUTDOWN_PENDING) {
2268 			asoc->state = SCTP_STATE_OPEN | SCTP_STATE_SHUTDOWN_PENDING;
2269 			sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
2270 			    stcb->sctp_ep, stcb, asoc->primary_destination);
2271 
2272 		} else {
2273 			asoc->state = SCTP_STATE_OPEN;
2274 		}
2275 		/* update RTO */
2276 		SCTP_STAT_INCR_COUNTER32(sctps_activeestab);
2277 		SCTP_STAT_INCR_GAUGE32(sctps_currestab);
2278 		if (asoc->overall_error_count == 0) {
2279 			net->RTO = sctp_calculate_rto(stcb, asoc, net,
2280 			    &asoc->time_entered);
2281 		}
2282 		SCTP_GETTIME_TIMEVAL(&asoc->time_entered);
2283 		sctp_ulp_notify(SCTP_NOTIFY_ASSOC_UP, stcb, 0, NULL);
2284 		if ((stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_TCPTYPE) ||
2285 		    (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_IN_TCPPOOL)) {
2286 			stcb->sctp_ep->sctp_flags |= SCTP_PCB_FLAGS_CONNECTED;
2287 			soisconnected(stcb->sctp_ep->sctp_socket);
2288 		}
2289 		sctp_timer_start(SCTP_TIMER_TYPE_HEARTBEAT, stcb->sctp_ep,
2290 		    stcb, net);
2291 		/*
2292 		 * since we did not send a HB make sure we don't double
2293 		 * things
2294 		 */
2295 		net->hb_responded = 1;
2296 
2297 		if (stcb->asoc.sctp_autoclose_ticks &&
2298 		    sctp_is_feature_on(stcb->sctp_ep, SCTP_PCB_FLAGS_AUTOCLOSE)) {
2299 			sctp_timer_start(SCTP_TIMER_TYPE_AUTOCLOSE,
2300 			    stcb->sctp_ep, stcb, NULL);
2301 		}
2302 		/*
2303 		 * set ASCONF timer if ASCONFs are pending and allowed (eg.
2304 		 * addresses changed when init/cookie echo in flight)
2305 		 */
2306 		if ((sctp_is_feature_on(stcb->sctp_ep, SCTP_PCB_FLAGS_DO_ASCONF)) &&
2307 		    (stcb->asoc.peer_supports_asconf) &&
2308 		    (!TAILQ_EMPTY(&stcb->asoc.asconf_queue))) {
2309 			sctp_timer_start(SCTP_TIMER_TYPE_ASCONF,
2310 			    stcb->sctp_ep, stcb,
2311 			    stcb->asoc.primary_destination);
2312 		}
2313 	}
2314 	/* Toss the cookie if I can */
2315 	sctp_toss_old_cookies(stcb, asoc);
2316 	if (!TAILQ_EMPTY(&asoc->sent_queue)) {
2317 		/* Restart the timer if we have pending data */
2318 		struct sctp_tmit_chunk *chk;
2319 
2320 		chk = TAILQ_FIRST(&asoc->sent_queue);
2321 		if (chk) {
2322 			sctp_timer_start(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
2323 			    stcb, chk->whoTo);
2324 		}
2325 	}
2326 }
2327 
2328 static void
2329 sctp_handle_ecn_echo(struct sctp_ecne_chunk *cp,
2330     struct sctp_tcb *stcb)
2331 {
2332 	struct sctp_nets *net;
2333 	struct sctp_tmit_chunk *lchk;
2334 	uint32_t tsn;
2335 
2336 	if (ntohs(cp->ch.chunk_length) != sizeof(struct sctp_ecne_chunk)) {
2337 		return;
2338 	}
2339 	SCTP_STAT_INCR(sctps_recvecne);
2340 	tsn = ntohl(cp->tsn);
2341 	/* ECN Nonce stuff: need a resync and disable the nonce sum check */
2342 	/* Also we make sure we disable the nonce_wait */
2343 	lchk = TAILQ_FIRST(&stcb->asoc.send_queue);
2344 	if (lchk == NULL) {
2345 		stcb->asoc.nonce_resync_tsn = stcb->asoc.sending_seq;
2346 	} else {
2347 		stcb->asoc.nonce_resync_tsn = lchk->rec.data.TSN_seq;
2348 	}
2349 	stcb->asoc.nonce_wait_for_ecne = 0;
2350 	stcb->asoc.nonce_sum_check = 0;
2351 
2352 	/* Find where it was sent, if possible */
2353 	net = NULL;
2354 	lchk = TAILQ_FIRST(&stcb->asoc.sent_queue);
2355 	while (lchk) {
2356 		if (lchk->rec.data.TSN_seq == tsn) {
2357 			net = lchk->whoTo;
2358 			break;
2359 		}
2360 		if (compare_with_wrap(lchk->rec.data.TSN_seq, tsn, MAX_SEQ))
2361 			break;
2362 		lchk = TAILQ_NEXT(lchk, sctp_next);
2363 	}
2364 	if (net == NULL)
2365 		/* default is we use the primary */
2366 		net = stcb->asoc.primary_destination;
2367 
2368 	if (compare_with_wrap(tsn, stcb->asoc.last_cwr_tsn, MAX_TSN)) {
2369 #ifdef SCTP_CWND_MONITOR
2370 		int old_cwnd;
2371 
2372 		old_cwnd = net->cwnd;
2373 #endif
2374 		SCTP_STAT_INCR(sctps_ecnereducedcwnd);
2375 		net->ssthresh = net->cwnd / 2;
2376 		if (net->ssthresh < net->mtu) {
2377 			net->ssthresh = net->mtu;
2378 			/* here back off the timer as well, to slow us down */
2379 			net->RTO <<= 2;
2380 		}
2381 		net->cwnd = net->ssthresh;
2382 #ifdef SCTP_CWND_MONITOR
2383 		sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
2384 #endif
2385 		/*
2386 		 * we reduce once every RTT. So we will only lower cwnd at
2387 		 * the next sending seq i.e. the resync_tsn.
2388 		 */
2389 		stcb->asoc.last_cwr_tsn = stcb->asoc.nonce_resync_tsn;
2390 	}
2391 	/*
2392 	 * We always send a CWR this way if our previous one was lost our
2393 	 * peer will get an update, or if it is not time again to reduce we
2394 	 * still get the cwr to the peer.
2395 	 */
2396 	sctp_send_cwr(stcb, net, tsn);
2397 }
2398 
2399 static void
2400 sctp_handle_ecn_cwr(struct sctp_cwr_chunk *cp, struct sctp_tcb *stcb)
2401 {
2402 	/*
2403 	 * Here we get a CWR from the peer. We must look in the outqueue and
2404 	 * make sure that we have a covered ECNE in teh control chunk part.
2405 	 * If so remove it.
2406 	 */
2407 	struct sctp_tmit_chunk *chk;
2408 	struct sctp_ecne_chunk *ecne;
2409 
2410 	TAILQ_FOREACH(chk, &stcb->asoc.control_send_queue, sctp_next) {
2411 		if (chk->rec.chunk_id.id != SCTP_ECN_ECHO) {
2412 			continue;
2413 		}
2414 		/*
2415 		 * Look for and remove if it is the right TSN. Since there
2416 		 * is only ONE ECNE on the control queue at any one time we
2417 		 * don't need to worry about more than one!
2418 		 */
2419 		ecne = mtod(chk->data, struct sctp_ecne_chunk *);
2420 		if (compare_with_wrap(ntohl(cp->tsn), ntohl(ecne->tsn),
2421 		    MAX_TSN) || (cp->tsn == ecne->tsn)) {
2422 			/* this covers this ECNE, we can remove it */
2423 			stcb->asoc.ecn_echo_cnt_onq--;
2424 			TAILQ_REMOVE(&stcb->asoc.control_send_queue, chk,
2425 			    sctp_next);
2426 			if (chk->data) {
2427 				sctp_m_freem(chk->data);
2428 				chk->data = NULL;
2429 			}
2430 			stcb->asoc.ctrl_queue_cnt--;
2431 			sctp_free_remote_addr(chk->whoTo);
2432 			sctp_free_a_chunk(stcb, chk);
2433 			break;
2434 		}
2435 	}
2436 }
2437 
2438 static void
2439 sctp_handle_shutdown_complete(struct sctp_shutdown_complete_chunk *cp,
2440     struct sctp_tcb *stcb, struct sctp_nets *net)
2441 {
2442 	struct sctp_association *asoc;
2443 
2444 #ifdef SCTP_DEBUG
2445 	if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
2446 		printf("sctp_handle_shutdown_complete: handling SHUTDOWN-COMPLETE\n");
2447 	}
2448 #endif
2449 	if (stcb == NULL)
2450 		return;
2451 
2452 	asoc = &stcb->asoc;
2453 	/* process according to association state */
2454 	if (SCTP_GET_STATE(asoc) != SCTP_STATE_SHUTDOWN_ACK_SENT) {
2455 		/* unexpected SHUTDOWN-COMPLETE... so ignore... */
2456 		SCTP_TCB_UNLOCK(stcb);
2457 		return;
2458 	}
2459 	/* notify upper layer protocol */
2460 	if (stcb->sctp_socket) {
2461 		sctp_ulp_notify(SCTP_NOTIFY_ASSOC_DOWN, stcb, 0, NULL);
2462 		/* are the queues empty? they should be */
2463 		if (!TAILQ_EMPTY(&asoc->send_queue) ||
2464 		    !TAILQ_EMPTY(&asoc->sent_queue) ||
2465 		    !TAILQ_EMPTY(&asoc->out_wheel)) {
2466 			sctp_report_all_outbound(stcb, 0);
2467 		}
2468 	}
2469 	/* stop the timer */
2470 	sctp_timer_stop(SCTP_TIMER_TYPE_SHUTDOWN, stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_21);
2471 	SCTP_STAT_INCR_COUNTER32(sctps_shutdown);
2472 	/* free the TCB */
2473 	sctp_free_assoc(stcb->sctp_ep, stcb, SCTP_NORMAL_PROC, SCTP_FROM_SCTP_INPUT + SCTP_LOC_22);
2474 	return;
2475 }
2476 
2477 static int
2478 process_chunk_drop(struct sctp_tcb *stcb, struct sctp_chunk_desc *desc,
2479     struct sctp_nets *net, uint8_t flg)
2480 {
2481 	switch (desc->chunk_type) {
2482 		case SCTP_DATA:
2483 		/* find the tsn to resend (possibly */
2484 		{
2485 			uint32_t tsn;
2486 			struct sctp_tmit_chunk *tp1;
2487 
2488 			tsn = ntohl(desc->tsn_ifany);
2489 			tp1 = TAILQ_FIRST(&stcb->asoc.sent_queue);
2490 			while (tp1) {
2491 				if (tp1->rec.data.TSN_seq == tsn) {
2492 					/* found it */
2493 					break;
2494 				}
2495 				if (compare_with_wrap(tp1->rec.data.TSN_seq, tsn,
2496 				    MAX_TSN)) {
2497 					/* not found */
2498 					tp1 = NULL;
2499 					break;
2500 				}
2501 				tp1 = TAILQ_NEXT(tp1, sctp_next);
2502 			}
2503 			if (tp1 == NULL) {
2504 				/*
2505 				 * Do it the other way , aka without paying
2506 				 * attention to queue seq order.
2507 				 */
2508 				SCTP_STAT_INCR(sctps_pdrpdnfnd);
2509 				tp1 = TAILQ_FIRST(&stcb->asoc.sent_queue);
2510 				while (tp1) {
2511 					if (tp1->rec.data.TSN_seq == tsn) {
2512 						/* found it */
2513 						break;
2514 					}
2515 					tp1 = TAILQ_NEXT(tp1, sctp_next);
2516 				}
2517 			}
2518 			if (tp1 == NULL) {
2519 				SCTP_STAT_INCR(sctps_pdrptsnnf);
2520 			}
2521 			if ((tp1) && (tp1->sent < SCTP_DATAGRAM_ACKED)) {
2522 				uint8_t *ddp;
2523 
2524 				if ((stcb->asoc.peers_rwnd == 0) &&
2525 				    ((flg & SCTP_FROM_MIDDLE_BOX) == 0)) {
2526 					SCTP_STAT_INCR(sctps_pdrpdiwnp);
2527 					return (0);
2528 				}
2529 				if (stcb->asoc.peers_rwnd == 0 &&
2530 				    (flg & SCTP_FROM_MIDDLE_BOX)) {
2531 					SCTP_STAT_INCR(sctps_pdrpdizrw);
2532 					return (0);
2533 				}
2534 				ddp = (uint8_t *) (mtod(tp1->data, caddr_t)+
2535 				    sizeof(struct sctp_data_chunk));
2536 				{
2537 					unsigned int iii;
2538 
2539 					for (iii = 0; iii < sizeof(desc->data_bytes);
2540 					    iii++) {
2541 						if (ddp[iii] != desc->data_bytes[iii]) {
2542 							SCTP_STAT_INCR(sctps_pdrpbadd);
2543 							return (-1);
2544 						}
2545 					}
2546 				}
2547 				/*
2548 				 * We zero out the nonce so resync not
2549 				 * needed
2550 				 */
2551 				tp1->rec.data.ect_nonce = 0;
2552 
2553 				if (tp1->do_rtt) {
2554 					/*
2555 					 * this guy had a RTO calculation
2556 					 * pending on it, cancel it
2557 					 */
2558 					tp1->whoTo->rto_pending = 0;
2559 					tp1->do_rtt = 0;
2560 				}
2561 				SCTP_STAT_INCR(sctps_pdrpmark);
2562 				if (tp1->sent != SCTP_DATAGRAM_RESEND)
2563 					sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
2564 				tp1->sent = SCTP_DATAGRAM_RESEND;
2565 				/*
2566 				 * mark it as if we were doing a FR, since
2567 				 * we will be getting gap ack reports behind
2568 				 * the info from the router.
2569 				 */
2570 				tp1->rec.data.doing_fast_retransmit = 1;
2571 				/*
2572 				 * mark the tsn with what sequences can
2573 				 * cause a new FR.
2574 				 */
2575 				if (TAILQ_EMPTY(&stcb->asoc.send_queue)) {
2576 					tp1->rec.data.fast_retran_tsn = stcb->asoc.sending_seq;
2577 				} else {
2578 					tp1->rec.data.fast_retran_tsn = (TAILQ_FIRST(&stcb->asoc.send_queue))->rec.data.TSN_seq;
2579 				}
2580 
2581 				/* restart the timer */
2582 				sctp_timer_stop(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
2583 				    stcb, tp1->whoTo, SCTP_FROM_SCTP_INPUT + SCTP_LOC_23);
2584 				sctp_timer_start(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
2585 				    stcb, tp1->whoTo);
2586 
2587 				/* fix counts and things */
2588 #ifdef SCTP_FLIGHT_LOGGING
2589 				sctp_misc_ints(SCTP_FLIGHT_LOG_DOWN,
2590 				    tp1->whoTo->flight_size,
2591 				    tp1->book_size,
2592 				    (uintptr_t) stcb,
2593 				    tp1->rec.data.TSN_seq);
2594 #endif
2595 				if (tp1->whoTo->flight_size >= tp1->book_size)
2596 					tp1->whoTo->flight_size -= tp1->book_size;
2597 				else
2598 					tp1->whoTo->flight_size = 0;
2599 
2600 				if (stcb->asoc.total_flight >= tp1->book_size) {
2601 					stcb->asoc.total_flight -= tp1->book_size;
2602 					if (stcb->asoc.total_flight_count > 0)
2603 						stcb->asoc.total_flight_count--;
2604 				} else {
2605 					stcb->asoc.total_flight = 0;
2606 					stcb->asoc.total_flight_count = 0;
2607 				}
2608 				tp1->snd_count--;
2609 			} {
2610 				/* audit code */
2611 				unsigned int audit;
2612 
2613 				audit = 0;
2614 				TAILQ_FOREACH(tp1, &stcb->asoc.sent_queue, sctp_next) {
2615 					if (tp1->sent == SCTP_DATAGRAM_RESEND)
2616 						audit++;
2617 				}
2618 				TAILQ_FOREACH(tp1, &stcb->asoc.control_send_queue,
2619 				    sctp_next) {
2620 					if (tp1->sent == SCTP_DATAGRAM_RESEND)
2621 						audit++;
2622 				}
2623 				if (audit != stcb->asoc.sent_queue_retran_cnt) {
2624 					printf("**Local Audit finds cnt:%d asoc cnt:%d\n",
2625 					    audit, stcb->asoc.sent_queue_retran_cnt);
2626 #ifndef SCTP_AUDITING_ENABLED
2627 					stcb->asoc.sent_queue_retran_cnt = audit;
2628 #endif
2629 				}
2630 			}
2631 		}
2632 		break;
2633 	case SCTP_ASCONF:
2634 		{
2635 			struct sctp_tmit_chunk *asconf;
2636 
2637 			TAILQ_FOREACH(asconf, &stcb->asoc.control_send_queue,
2638 			    sctp_next) {
2639 				if (asconf->rec.chunk_id.id == SCTP_ASCONF) {
2640 					break;
2641 				}
2642 			}
2643 			if (asconf) {
2644 				if (asconf->sent != SCTP_DATAGRAM_RESEND)
2645 					sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
2646 				asconf->sent = SCTP_DATAGRAM_RESEND;
2647 				asconf->snd_count--;
2648 			}
2649 		}
2650 		break;
2651 	case SCTP_INITIATION:
2652 		/* resend the INIT */
2653 		stcb->asoc.dropped_special_cnt++;
2654 		if (stcb->asoc.dropped_special_cnt < SCTP_RETRY_DROPPED_THRESH) {
2655 			/*
2656 			 * If we can get it in, in a few attempts we do
2657 			 * this, otherwise we let the timer fire.
2658 			 */
2659 			sctp_timer_stop(SCTP_TIMER_TYPE_INIT, stcb->sctp_ep,
2660 			    stcb, net, SCTP_FROM_SCTP_INPUT + SCTP_LOC_24);
2661 			sctp_send_initiate(stcb->sctp_ep, stcb);
2662 		}
2663 		break;
2664 	case SCTP_SELECTIVE_ACK:
2665 		/* resend the sack */
2666 		sctp_send_sack(stcb);
2667 		break;
2668 	case SCTP_HEARTBEAT_REQUEST:
2669 		/* resend a demand HB */
2670 		sctp_send_hb(stcb, 1, net);
2671 		break;
2672 	case SCTP_SHUTDOWN:
2673 		sctp_send_shutdown(stcb, net);
2674 		break;
2675 	case SCTP_SHUTDOWN_ACK:
2676 		sctp_send_shutdown_ack(stcb, net);
2677 		break;
2678 	case SCTP_COOKIE_ECHO:
2679 		{
2680 			struct sctp_tmit_chunk *cookie;
2681 
2682 			cookie = NULL;
2683 			TAILQ_FOREACH(cookie, &stcb->asoc.control_send_queue,
2684 			    sctp_next) {
2685 				if (cookie->rec.chunk_id.id == SCTP_COOKIE_ECHO) {
2686 					break;
2687 				}
2688 			}
2689 			if (cookie) {
2690 				if (cookie->sent != SCTP_DATAGRAM_RESEND)
2691 					sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
2692 				cookie->sent = SCTP_DATAGRAM_RESEND;
2693 				sctp_stop_all_cookie_timers(stcb);
2694 			}
2695 		}
2696 		break;
2697 	case SCTP_COOKIE_ACK:
2698 		sctp_send_cookie_ack(stcb);
2699 		break;
2700 	case SCTP_ASCONF_ACK:
2701 		/* resend last asconf ack */
2702 		sctp_send_asconf_ack(stcb, 1);
2703 		break;
2704 	case SCTP_FORWARD_CUM_TSN:
2705 		send_forward_tsn(stcb, &stcb->asoc);
2706 		break;
2707 		/* can't do anything with these */
2708 	case SCTP_PACKET_DROPPED:
2709 	case SCTP_INITIATION_ACK:	/* this should not happen */
2710 	case SCTP_HEARTBEAT_ACK:
2711 	case SCTP_ABORT_ASSOCIATION:
2712 	case SCTP_OPERATION_ERROR:
2713 	case SCTP_SHUTDOWN_COMPLETE:
2714 	case SCTP_ECN_ECHO:
2715 	case SCTP_ECN_CWR:
2716 	default:
2717 		break;
2718 	}
2719 	return (0);
2720 }
2721 
2722 void
2723 sctp_reset_in_stream(struct sctp_tcb *stcb, int number_entries, uint16_t * list)
2724 {
2725 	int i;
2726 	uint16_t temp;
2727 
2728 	/*
2729 	 * We set things to 0xffff since this is the last delivered sequence
2730 	 * and we will be sending in 0 after the reset.
2731 	 */
2732 
2733 	if (number_entries) {
2734 		for (i = 0; i < number_entries; i++) {
2735 			temp = ntohs(list[i]);
2736 			if (temp >= stcb->asoc.streamincnt) {
2737 				continue;
2738 			}
2739 			stcb->asoc.strmin[temp].last_sequence_delivered = 0xffff;
2740 		}
2741 	} else {
2742 		list = NULL;
2743 		for (i = 0; i < stcb->asoc.streamincnt; i++) {
2744 			stcb->asoc.strmin[i].last_sequence_delivered = 0xffff;
2745 		}
2746 	}
2747 	sctp_ulp_notify(SCTP_NOTIFY_STR_RESET_RECV, stcb, number_entries, (void *)list);
2748 }
2749 
2750 static void
2751 sctp_reset_out_streams(struct sctp_tcb *stcb, int number_entries, uint16_t * list)
2752 {
2753 	int i;
2754 
2755 	if (number_entries == 0) {
2756 		for (i = 0; i < stcb->asoc.streamoutcnt; i++) {
2757 			stcb->asoc.strmout[i].next_sequence_sent = 0;
2758 		}
2759 	} else if (number_entries) {
2760 		for (i = 0; i < number_entries; i++) {
2761 			uint16_t temp;
2762 
2763 			temp = ntohs(list[i]);
2764 			if (temp >= stcb->asoc.streamoutcnt) {
2765 				/* no such stream */
2766 				continue;
2767 			}
2768 			stcb->asoc.strmout[temp].next_sequence_sent = 0;
2769 		}
2770 	}
2771 	sctp_ulp_notify(SCTP_NOTIFY_STR_RESET_SEND, stcb, number_entries, (void *)list);
2772 }
2773 
2774 
2775 struct sctp_stream_reset_out_request *
2776 sctp_find_stream_reset(struct sctp_tcb *stcb, uint32_t seq, struct sctp_tmit_chunk **bchk)
2777 {
2778 	struct sctp_association *asoc;
2779 	struct sctp_stream_reset_out_req *req;
2780 	struct sctp_stream_reset_out_request *r;
2781 	struct sctp_tmit_chunk *chk;
2782 	int len, clen;
2783 
2784 	asoc = &stcb->asoc;
2785 	if (TAILQ_EMPTY(&stcb->asoc.control_send_queue)) {
2786 		return (NULL);
2787 	}
2788 	if (stcb->asoc.str_reset == NULL) {
2789 		return (NULL);
2790 	}
2791 	chk = stcb->asoc.str_reset;
2792 	if (chk->data == NULL) {
2793 		return (NULL);
2794 	}
2795 	if (bchk) {
2796 		/* he wants a copy of the chk pointer */
2797 		*bchk = chk;
2798 	}
2799 	clen = chk->send_size;
2800 	req = mtod(chk->data, struct sctp_stream_reset_out_req *);
2801 	r = &req->sr_req;
2802 	if (ntohl(r->request_seq) == seq) {
2803 		/* found it */
2804 		return (r);
2805 	}
2806 	len = SCTP_SIZE32(ntohs(r->ph.param_length));
2807 	if (clen > (len + (int)sizeof(struct sctp_chunkhdr))) {
2808 		/* move to the next one, there can only be a max of two */
2809 		r = (struct sctp_stream_reset_out_request *)((caddr_t)r + len);
2810 		if (ntohl(r->request_seq) == seq) {
2811 			return (r);
2812 		}
2813 	}
2814 	/* that seq is not here */
2815 	return (NULL);
2816 }
2817 
2818 static void
2819 sctp_clean_up_stream_reset(struct sctp_tcb *stcb)
2820 {
2821 	struct sctp_association *asoc;
2822 	struct sctp_tmit_chunk *chk = stcb->asoc.str_reset;
2823 
2824 	if (stcb->asoc.str_reset == NULL) {
2825 		return;
2826 	}
2827 	asoc = &stcb->asoc;
2828 
2829 	sctp_timer_stop(SCTP_TIMER_TYPE_STRRESET, stcb->sctp_ep, stcb, chk->whoTo, SCTP_FROM_SCTP_INPUT + SCTP_LOC_25);
2830 	TAILQ_REMOVE(&asoc->control_send_queue,
2831 	    chk,
2832 	    sctp_next);
2833 	if (chk->data) {
2834 		sctp_m_freem(chk->data);
2835 		chk->data = NULL;
2836 	}
2837 	asoc->ctrl_queue_cnt--;
2838 	sctp_free_remote_addr(chk->whoTo);
2839 
2840 	sctp_free_a_chunk(stcb, chk);
2841 	stcb->asoc.str_reset = NULL;
2842 }
2843 
2844 
2845 static int
2846 sctp_handle_stream_reset_response(struct sctp_tcb *stcb,
2847     uint32_t seq, uint32_t action,
2848     struct sctp_stream_reset_response *respin)
2849 {
2850 	uint16_t type;
2851 	int lparm_len;
2852 	struct sctp_association *asoc = &stcb->asoc;
2853 	struct sctp_tmit_chunk *chk;
2854 	struct sctp_stream_reset_out_request *srparam;
2855 	int number_entries;
2856 
2857 	if (asoc->stream_reset_outstanding == 0) {
2858 		/* duplicate */
2859 		return (0);
2860 	}
2861 	if (seq == stcb->asoc.str_reset_seq_out) {
2862 		srparam = sctp_find_stream_reset(stcb, seq, &chk);
2863 		if (srparam) {
2864 			stcb->asoc.str_reset_seq_out++;
2865 			type = ntohs(srparam->ph.param_type);
2866 			lparm_len = ntohs(srparam->ph.param_length);
2867 			if (type == SCTP_STR_RESET_OUT_REQUEST) {
2868 				number_entries = (lparm_len - sizeof(struct sctp_stream_reset_out_request)) / sizeof(uint16_t);
2869 				asoc->stream_reset_out_is_outstanding = 0;
2870 				if (asoc->stream_reset_outstanding)
2871 					asoc->stream_reset_outstanding--;
2872 				if (action == SCTP_STREAM_RESET_PERFORMED) {
2873 					/* do it */
2874 					sctp_reset_out_streams(stcb, number_entries, srparam->list_of_streams);
2875 				} else {
2876 					sctp_ulp_notify(SCTP_NOTIFY_STR_RESET_FAILED_OUT, stcb, number_entries, srparam->list_of_streams);
2877 				}
2878 			} else if (type == SCTP_STR_RESET_IN_REQUEST) {
2879 				/* Answered my request */
2880 				number_entries = (lparm_len - sizeof(struct sctp_stream_reset_in_request)) / sizeof(uint16_t);
2881 				if (asoc->stream_reset_outstanding)
2882 					asoc->stream_reset_outstanding--;
2883 				if (action != SCTP_STREAM_RESET_PERFORMED) {
2884 					sctp_ulp_notify(SCTP_NOTIFY_STR_RESET_FAILED_IN, stcb, number_entries, srparam->list_of_streams);
2885 				}
2886 			} else if (type == SCTP_STR_RESET_TSN_REQUEST) {
2887 				/**
2888 				 * a) Adopt the new in tsn.
2889 				 * b) reset the map
2890 				 * c) Adopt the new out-tsn
2891 				 */
2892 				struct sctp_stream_reset_response_tsn *resp;
2893 				struct sctp_forward_tsn_chunk fwdtsn;
2894 				int abort_flag = 0;
2895 
2896 				if (respin == NULL) {
2897 					/* huh ? */
2898 					return (0);
2899 				}
2900 				if (action == SCTP_STREAM_RESET_PERFORMED) {
2901 					resp = (struct sctp_stream_reset_response_tsn *)respin;
2902 					asoc->stream_reset_outstanding--;
2903 					fwdtsn.ch.chunk_length = htons(sizeof(struct sctp_forward_tsn_chunk));
2904 					fwdtsn.ch.chunk_type = SCTP_FORWARD_CUM_TSN;
2905 					fwdtsn.new_cumulative_tsn = htonl(ntohl(resp->senders_next_tsn) - 1);
2906 					sctp_handle_forward_tsn(stcb, &fwdtsn, &abort_flag);
2907 					if (abort_flag) {
2908 						return (1);
2909 					}
2910 					stcb->asoc.highest_tsn_inside_map = (ntohl(resp->senders_next_tsn) - 1);
2911 					stcb->asoc.cumulative_tsn = stcb->asoc.highest_tsn_inside_map;
2912 					stcb->asoc.mapping_array_base_tsn = ntohl(resp->senders_next_tsn);
2913 					memset(stcb->asoc.mapping_array, 0, stcb->asoc.mapping_array_size);
2914 					stcb->asoc.sending_seq = ntohl(resp->receivers_next_tsn);
2915 					stcb->asoc.last_acked_seq = stcb->asoc.cumulative_tsn;
2916 
2917 					sctp_reset_out_streams(stcb, 0, (uint16_t *) NULL);
2918 					sctp_reset_in_stream(stcb, 0, (uint16_t *) NULL);
2919 
2920 				}
2921 			}
2922 			/* get rid of the request and get the request flags */
2923 			if (asoc->stream_reset_outstanding == 0) {
2924 				sctp_clean_up_stream_reset(stcb);
2925 			}
2926 		}
2927 	}
2928 	return (0);
2929 }
2930 
2931 static void
2932 sctp_handle_str_reset_request_in(struct sctp_tcb *stcb,
2933     struct sctp_tmit_chunk *chk,
2934     struct sctp_stream_reset_in_request *req)
2935 {
2936 	uint32_t seq;
2937 	int len, i;
2938 	int number_entries;
2939 	uint16_t temp;
2940 
2941 	/*
2942 	 * peer wants me to send a str-reset to him for my outgoing seq's if
2943 	 * seq_in is right.
2944 	 */
2945 	struct sctp_association *asoc = &stcb->asoc;
2946 
2947 	seq = ntohl(req->request_seq);
2948 	if (asoc->str_reset_seq_in == seq) {
2949 		if (stcb->asoc.stream_reset_out_is_outstanding == 0) {
2950 			len = ntohs(req->ph.param_length);
2951 			number_entries = ((len - sizeof(struct sctp_stream_reset_in_request)) / sizeof(uint16_t));
2952 			for (i = 0; i < number_entries; i++) {
2953 				temp = ntohs(req->list_of_streams[i]);
2954 				req->list_of_streams[i] = temp;
2955 			}
2956 			/* move the reset action back one */
2957 			asoc->last_reset_action[1] = asoc->last_reset_action[0];
2958 			asoc->last_reset_action[0] = SCTP_STREAM_RESET_PERFORMED;
2959 			sctp_add_stream_reset_out(chk, number_entries, req->list_of_streams,
2960 			    asoc->str_reset_seq_out,
2961 			    seq, (asoc->sending_seq - 1));
2962 			asoc->stream_reset_out_is_outstanding = 1;
2963 			asoc->str_reset = chk;
2964 			sctp_timer_start(SCTP_TIMER_TYPE_STRRESET, stcb->sctp_ep, stcb, chk->whoTo);
2965 			stcb->asoc.stream_reset_outstanding++;
2966 		} else {
2967 			/* Can't do it, since we have sent one out */
2968 			asoc->last_reset_action[1] = asoc->last_reset_action[0];
2969 			asoc->last_reset_action[0] = SCTP_STREAM_RESET_TRY_LATER;
2970 			sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[0]);
2971 		}
2972 		asoc->str_reset_seq_in++;
2973 	} else if (asoc->str_reset_seq_in - 1 == seq) {
2974 		sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[0]);
2975 	} else if (asoc->str_reset_seq_in - 2 == seq) {
2976 		sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[1]);
2977 	} else {
2978 		sctp_add_stream_reset_result(chk, seq, SCTP_STREAM_RESET_BAD_SEQNO);
2979 	}
2980 }
2981 
2982 static int
2983 sctp_handle_str_reset_request_tsn(struct sctp_tcb *stcb,
2984     struct sctp_tmit_chunk *chk,
2985     struct sctp_stream_reset_tsn_request *req)
2986 {
2987 	/* reset all in and out and update the tsn */
2988 	/*
2989 	 * A) reset my str-seq's on in and out. B) Select a receive next,
2990 	 * and set cum-ack to it. Also process this selected number as a
2991 	 * fwd-tsn as well. C) set in the response my next sending seq.
2992 	 */
2993 	struct sctp_forward_tsn_chunk fwdtsn;
2994 	struct sctp_association *asoc = &stcb->asoc;
2995 	int abort_flag = 0;
2996 	uint32_t seq;
2997 
2998 	seq = ntohl(req->request_seq);
2999 	if (asoc->str_reset_seq_in == seq) {
3000 		fwdtsn.ch.chunk_length = htons(sizeof(struct sctp_forward_tsn_chunk));
3001 		fwdtsn.ch.chunk_type = SCTP_FORWARD_CUM_TSN;
3002 		fwdtsn.ch.chunk_flags = 0;
3003 		fwdtsn.new_cumulative_tsn = htonl(stcb->asoc.highest_tsn_inside_map + 1);
3004 		sctp_handle_forward_tsn(stcb, &fwdtsn, &abort_flag);
3005 		if (abort_flag) {
3006 			return (1);
3007 		}
3008 		stcb->asoc.highest_tsn_inside_map += SCTP_STREAM_RESET_TSN_DELTA;
3009 		stcb->asoc.cumulative_tsn = stcb->asoc.highest_tsn_inside_map;
3010 		stcb->asoc.mapping_array_base_tsn = stcb->asoc.highest_tsn_inside_map + 1;
3011 		memset(stcb->asoc.mapping_array, 0, stcb->asoc.mapping_array_size);
3012 		atomic_add_int(&stcb->asoc.sending_seq, 1);
3013 		/* save off historical data for retrans */
3014 		stcb->asoc.last_sending_seq[1] = stcb->asoc.last_sending_seq[0];
3015 		stcb->asoc.last_sending_seq[0] = stcb->asoc.sending_seq;
3016 		stcb->asoc.last_base_tsnsent[1] = stcb->asoc.last_base_tsnsent[0];
3017 		stcb->asoc.last_base_tsnsent[0] = stcb->asoc.mapping_array_base_tsn;
3018 
3019 		sctp_add_stream_reset_result_tsn(chk,
3020 		    ntohl(req->request_seq),
3021 		    SCTP_STREAM_RESET_PERFORMED,
3022 		    stcb->asoc.sending_seq,
3023 		    stcb->asoc.mapping_array_base_tsn);
3024 		sctp_reset_out_streams(stcb, 0, (uint16_t *) NULL);
3025 		sctp_reset_in_stream(stcb, 0, (uint16_t *) NULL);
3026 		stcb->asoc.last_reset_action[1] = stcb->asoc.last_reset_action[0];
3027 		stcb->asoc.last_reset_action[0] = SCTP_STREAM_RESET_PERFORMED;
3028 
3029 		asoc->str_reset_seq_in++;
3030 	} else if (asoc->str_reset_seq_in - 1 == seq) {
3031 		sctp_add_stream_reset_result_tsn(chk, seq, asoc->last_reset_action[0],
3032 		    stcb->asoc.last_sending_seq[0],
3033 		    stcb->asoc.last_base_tsnsent[0]
3034 		    );
3035 	} else if (asoc->str_reset_seq_in - 2 == seq) {
3036 		sctp_add_stream_reset_result_tsn(chk, seq, asoc->last_reset_action[1],
3037 		    stcb->asoc.last_sending_seq[1],
3038 		    stcb->asoc.last_base_tsnsent[1]
3039 		    );
3040 	} else {
3041 		sctp_add_stream_reset_result(chk, seq, SCTP_STREAM_RESET_BAD_SEQNO);
3042 	}
3043 	return (0);
3044 }
3045 
3046 static void
3047 sctp_handle_str_reset_request_out(struct sctp_tcb *stcb,
3048     struct sctp_tmit_chunk *chk,
3049     struct sctp_stream_reset_out_request *req)
3050 {
3051 	uint32_t seq, tsn;
3052 	int number_entries, len;
3053 	struct sctp_association *asoc = &stcb->asoc;
3054 
3055 	seq = ntohl(req->request_seq);
3056 
3057 	/* now if its not a duplicate we process it */
3058 	if (asoc->str_reset_seq_in == seq) {
3059 		len = ntohs(req->ph.param_length);
3060 		number_entries = ((len - sizeof(struct sctp_stream_reset_out_request)) / sizeof(uint16_t));
3061 		/*
3062 		 * the sender is resetting, handle the list issue.. we must
3063 		 * a) verify if we can do the reset, if so no problem b) If
3064 		 * we can't do the reset we must copy the request. c) queue
3065 		 * it, and setup the data in processor to trigger it off
3066 		 * when needed and dequeue all the queued data.
3067 		 */
3068 		tsn = ntohl(req->send_reset_at_tsn);
3069 
3070 		/* move the reset action back one */
3071 		asoc->last_reset_action[1] = asoc->last_reset_action[0];
3072 		if ((tsn == asoc->cumulative_tsn) ||
3073 		    (compare_with_wrap(asoc->cumulative_tsn, tsn, MAX_TSN))) {
3074 			/* we can do it now */
3075 			sctp_reset_in_stream(stcb, number_entries, req->list_of_streams);
3076 			sctp_add_stream_reset_result(chk, seq, SCTP_STREAM_RESET_PERFORMED);
3077 			asoc->last_reset_action[0] = SCTP_STREAM_RESET_PERFORMED;
3078 		} else {
3079 			/*
3080 			 * we must queue it up and thus wait for the TSN's
3081 			 * to arrive that are at or before tsn
3082 			 */
3083 			struct sctp_stream_reset_list *liste;
3084 			int siz;
3085 
3086 			siz = sizeof(struct sctp_stream_reset_list) + (number_entries * sizeof(uint16_t));
3087 			SCTP_MALLOC(liste, struct sctp_stream_reset_list *,
3088 			    siz, "StrRstList");
3089 			if (liste == NULL) {
3090 				/* gak out of memory */
3091 				sctp_add_stream_reset_result(chk, seq, SCTP_STREAM_RESET_DENIED);
3092 				asoc->last_reset_action[0] = SCTP_STREAM_RESET_DENIED;
3093 				return;
3094 			}
3095 			liste->tsn = tsn;
3096 			liste->number_entries = number_entries;
3097 			memcpy(&liste->req, req,
3098 			    (sizeof(struct sctp_stream_reset_out_request) + (number_entries * sizeof(uint16_t))));
3099 			TAILQ_INSERT_TAIL(&asoc->resetHead, liste, next_resp);
3100 			sctp_add_stream_reset_result(chk, seq, SCTP_STREAM_RESET_PERFORMED);
3101 			asoc->last_reset_action[0] = SCTP_STREAM_RESET_PERFORMED;
3102 		}
3103 		asoc->str_reset_seq_in++;
3104 	} else if ((asoc->str_reset_seq_in - 1) == seq) {
3105 		/*
3106 		 * one seq back, just echo back last action since my
3107 		 * response was lost.
3108 		 */
3109 		sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[0]);
3110 	} else if ((asoc->str_reset_seq_in - 2) == seq) {
3111 		/*
3112 		 * two seq back, just echo back last action since my
3113 		 * response was lost.
3114 		 */
3115 		sctp_add_stream_reset_result(chk, seq, asoc->last_reset_action[1]);
3116 	} else {
3117 		sctp_add_stream_reset_result(chk, seq, SCTP_STREAM_RESET_BAD_SEQNO);
3118 	}
3119 }
3120 
3121 static int
3122 sctp_handle_stream_reset(struct sctp_tcb *stcb, struct sctp_stream_reset_out_req *sr_req)
3123 {
3124 	int chk_length, param_len, ptype;
3125 	uint32_t seq;
3126 	int num_req = 0;
3127 	struct sctp_tmit_chunk *chk;
3128 	struct sctp_chunkhdr *ch;
3129 	struct sctp_paramhdr *ph;
3130 	int ret_code = 0;
3131 	int num_param = 0;
3132 
3133 	/* now it may be a reset or a reset-response */
3134 	chk_length = ntohs(sr_req->ch.chunk_length);
3135 
3136 	/* setup for adding the response */
3137 	sctp_alloc_a_chunk(stcb, chk);
3138 	if (chk == NULL) {
3139 		return (ret_code);
3140 	}
3141 	chk->rec.chunk_id.id = SCTP_STREAM_RESET;
3142 	chk->asoc = &stcb->asoc;
3143 	chk->no_fr_allowed = 0;
3144 	chk->book_size = chk->send_size = sizeof(struct sctp_chunkhdr);
3145 	chk->book_size_scale = 0;
3146 	chk->data = sctp_get_mbuf_for_msg(MCLBYTES, 0, M_DONTWAIT, 1, MT_DATA);
3147 	if (chk->data == NULL) {
3148 strres_nochunk:
3149 		if (chk->data) {
3150 			sctp_m_freem(chk->data);
3151 			chk->data = NULL;
3152 		}
3153 		sctp_free_a_chunk(stcb, chk);
3154 		return (ret_code);
3155 	}
3156 	SCTP_BUF_RESV_UF(chk->data, SCTP_MIN_OVERHEAD);
3157 
3158 	/* setup chunk parameters */
3159 	chk->sent = SCTP_DATAGRAM_UNSENT;
3160 	chk->snd_count = 0;
3161 	chk->whoTo = stcb->asoc.primary_destination;
3162 	atomic_add_int(&chk->whoTo->ref_count, 1);
3163 
3164 	ch = mtod(chk->data, struct sctp_chunkhdr *);
3165 	ch->chunk_type = SCTP_STREAM_RESET;
3166 	ch->chunk_flags = 0;
3167 	ch->chunk_length = htons(chk->send_size);
3168 	SCTP_BUF_LEN(chk->data) = SCTP_SIZE32(chk->send_size);
3169 
3170 	ph = (struct sctp_paramhdr *)&sr_req->sr_req;
3171 	while ((size_t)chk_length >= sizeof(struct sctp_stream_reset_tsn_request)) {
3172 		param_len = ntohs(ph->param_length);
3173 		if (param_len < (int)sizeof(struct sctp_stream_reset_tsn_request)) {
3174 			/* bad param */
3175 			break;
3176 		}
3177 		ptype = ntohs(ph->param_type);
3178 		num_param++;
3179 		if (num_param > SCTP_MAX_RESET_PARAMS) {
3180 			/* hit the max of parameters already sorry.. */
3181 			break;
3182 		}
3183 		if (ptype == SCTP_STR_RESET_OUT_REQUEST) {
3184 			struct sctp_stream_reset_out_request *req_out;
3185 
3186 			req_out = (struct sctp_stream_reset_out_request *)ph;
3187 			num_req++;
3188 			if (stcb->asoc.stream_reset_outstanding) {
3189 				seq = ntohl(req_out->response_seq);
3190 				if (seq == stcb->asoc.str_reset_seq_out) {
3191 					/* implicit ack */
3192 					sctp_handle_stream_reset_response(stcb, seq, SCTP_STREAM_RESET_PERFORMED, NULL);
3193 				}
3194 			}
3195 			sctp_handle_str_reset_request_out(stcb, chk, req_out);
3196 		} else if (ptype == SCTP_STR_RESET_IN_REQUEST) {
3197 			struct sctp_stream_reset_in_request *req_in;
3198 
3199 			num_req++;
3200 			req_in = (struct sctp_stream_reset_in_request *)ph;
3201 			sctp_handle_str_reset_request_in(stcb, chk, req_in);
3202 		} else if (ptype == SCTP_STR_RESET_TSN_REQUEST) {
3203 			struct sctp_stream_reset_tsn_request *req_tsn;
3204 
3205 			num_req++;
3206 			req_tsn = (struct sctp_stream_reset_tsn_request *)ph;
3207 			if (sctp_handle_str_reset_request_tsn(stcb, chk, req_tsn)) {
3208 				ret_code = 1;
3209 				goto strres_nochunk;
3210 			}
3211 			/* no more */
3212 			break;
3213 		} else if (ptype == SCTP_STR_RESET_RESPONSE) {
3214 			struct sctp_stream_reset_response *resp;
3215 			uint32_t result;
3216 
3217 			resp = (struct sctp_stream_reset_response *)ph;
3218 			seq = ntohl(resp->response_seq);
3219 			result = ntohl(resp->result);
3220 			if (sctp_handle_stream_reset_response(stcb, seq, result, resp)) {
3221 				ret_code = 1;
3222 				goto strres_nochunk;
3223 			}
3224 		} else {
3225 			break;
3226 		}
3227 
3228 		ph = (struct sctp_paramhdr *)((caddr_t)ph + SCTP_SIZE32(param_len));
3229 		chk_length -= SCTP_SIZE32(param_len);
3230 	}
3231 	if (num_req == 0) {
3232 		/* we have no response free the stuff */
3233 		goto strres_nochunk;
3234 	}
3235 	/* ok we have a chunk to link in */
3236 	TAILQ_INSERT_TAIL(&stcb->asoc.control_send_queue,
3237 	    chk,
3238 	    sctp_next);
3239 	stcb->asoc.ctrl_queue_cnt++;
3240 	return (ret_code);
3241 }
3242 
3243 /*
3244  * Handle a router or endpoints report of a packet loss, there are two ways
3245  * to handle this, either we get the whole packet and must disect it
3246  * ourselves (possibly with truncation and or corruption) or it is a summary
3247  * from a middle box that did the disectting for us.
3248  */
3249 static void
3250 sctp_handle_packet_dropped(struct sctp_pktdrop_chunk *cp,
3251     struct sctp_tcb *stcb, struct sctp_nets *net)
3252 {
3253 	uint32_t bottle_bw, on_queue;
3254 	uint16_t trunc_len;
3255 	unsigned int chlen;
3256 	unsigned int at;
3257 	struct sctp_chunk_desc desc;
3258 	struct sctp_chunkhdr *ch;
3259 
3260 	chlen = ntohs(cp->ch.chunk_length);
3261 	chlen -= sizeof(struct sctp_pktdrop_chunk);
3262 	/* XXX possible chlen underflow */
3263 	if (chlen == 0) {
3264 		ch = NULL;
3265 		if (cp->ch.chunk_flags & SCTP_FROM_MIDDLE_BOX)
3266 			SCTP_STAT_INCR(sctps_pdrpbwrpt);
3267 	} else {
3268 		ch = (struct sctp_chunkhdr *)(cp->data + sizeof(struct sctphdr));
3269 		chlen -= sizeof(struct sctphdr);
3270 		/* XXX possible chlen underflow */
3271 		memset(&desc, 0, sizeof(desc));
3272 	}
3273 	trunc_len = (uint16_t) ntohs(cp->trunc_len);
3274 	/* now the chunks themselves */
3275 	while ((ch != NULL) && (chlen >= sizeof(struct sctp_chunkhdr))) {
3276 		desc.chunk_type = ch->chunk_type;
3277 		/* get amount we need to move */
3278 		at = ntohs(ch->chunk_length);
3279 		if (at < sizeof(struct sctp_chunkhdr)) {
3280 			/* corrupt chunk, maybe at the end? */
3281 			SCTP_STAT_INCR(sctps_pdrpcrupt);
3282 			break;
3283 		}
3284 		if (trunc_len == 0) {
3285 			/* we are supposed to have all of it */
3286 			if (at > chlen) {
3287 				/* corrupt skip it */
3288 				SCTP_STAT_INCR(sctps_pdrpcrupt);
3289 				break;
3290 			}
3291 		} else {
3292 			/* is there enough of it left ? */
3293 			if (desc.chunk_type == SCTP_DATA) {
3294 				if (chlen < (sizeof(struct sctp_data_chunk) +
3295 				    sizeof(desc.data_bytes))) {
3296 					break;
3297 				}
3298 			} else {
3299 				if (chlen < sizeof(struct sctp_chunkhdr)) {
3300 					break;
3301 				}
3302 			}
3303 		}
3304 		if (desc.chunk_type == SCTP_DATA) {
3305 			/* can we get out the tsn? */
3306 			if ((cp->ch.chunk_flags & SCTP_FROM_MIDDLE_BOX))
3307 				SCTP_STAT_INCR(sctps_pdrpmbda);
3308 
3309 			if (chlen >= (sizeof(struct sctp_data_chunk) + sizeof(uint32_t))) {
3310 				/* yep */
3311 				struct sctp_data_chunk *dcp;
3312 				uint8_t *ddp;
3313 				unsigned int iii;
3314 
3315 				dcp = (struct sctp_data_chunk *)ch;
3316 				ddp = (uint8_t *) (dcp + 1);
3317 				for (iii = 0; iii < sizeof(desc.data_bytes); iii++) {
3318 					desc.data_bytes[iii] = ddp[iii];
3319 				}
3320 				desc.tsn_ifany = dcp->dp.tsn;
3321 			} else {
3322 				/* nope we are done. */
3323 				SCTP_STAT_INCR(sctps_pdrpnedat);
3324 				break;
3325 			}
3326 		} else {
3327 			if ((cp->ch.chunk_flags & SCTP_FROM_MIDDLE_BOX))
3328 				SCTP_STAT_INCR(sctps_pdrpmbct);
3329 		}
3330 
3331 		if (process_chunk_drop(stcb, &desc, net, cp->ch.chunk_flags)) {
3332 			SCTP_STAT_INCR(sctps_pdrppdbrk);
3333 			break;
3334 		}
3335 		if (SCTP_SIZE32(at) > chlen) {
3336 			break;
3337 		}
3338 		chlen -= SCTP_SIZE32(at);
3339 		if (chlen < sizeof(struct sctp_chunkhdr)) {
3340 			/* done, none left */
3341 			break;
3342 		}
3343 		ch = (struct sctp_chunkhdr *)((caddr_t)ch + SCTP_SIZE32(at));
3344 	}
3345 	/* Now update any rwnd --- possibly */
3346 	if ((cp->ch.chunk_flags & SCTP_FROM_MIDDLE_BOX) == 0) {
3347 		/* From a peer, we get a rwnd report */
3348 		uint32_t a_rwnd;
3349 
3350 		SCTP_STAT_INCR(sctps_pdrpfehos);
3351 
3352 		bottle_bw = ntohl(cp->bottle_bw);
3353 		on_queue = ntohl(cp->current_onq);
3354 		if (bottle_bw && on_queue) {
3355 			/* a rwnd report is in here */
3356 			if (bottle_bw > on_queue)
3357 				a_rwnd = bottle_bw - on_queue;
3358 			else
3359 				a_rwnd = 0;
3360 
3361 			if (a_rwnd == 0)
3362 				stcb->asoc.peers_rwnd = 0;
3363 			else {
3364 				if (a_rwnd > stcb->asoc.total_flight) {
3365 					stcb->asoc.peers_rwnd =
3366 					    a_rwnd - stcb->asoc.total_flight;
3367 				} else {
3368 					stcb->asoc.peers_rwnd = 0;
3369 				}
3370 				if (stcb->asoc.peers_rwnd <
3371 				    stcb->sctp_ep->sctp_ep.sctp_sws_sender) {
3372 					/* SWS sender side engages */
3373 					stcb->asoc.peers_rwnd = 0;
3374 				}
3375 			}
3376 		}
3377 	} else {
3378 		SCTP_STAT_INCR(sctps_pdrpfmbox);
3379 	}
3380 
3381 	/* now middle boxes in sat networks get a cwnd bump */
3382 	if ((cp->ch.chunk_flags & SCTP_FROM_MIDDLE_BOX) &&
3383 	    (stcb->asoc.sat_t3_loss_recovery == 0) &&
3384 	    (stcb->asoc.sat_network)) {
3385 		/*
3386 		 * This is debateable but for sat networks it makes sense
3387 		 * Note if a T3 timer has went off, we will prohibit any
3388 		 * changes to cwnd until we exit the t3 loss recovery.
3389 		 */
3390 		uint32_t bw_avail;
3391 		int rtt, incr;
3392 
3393 #ifdef SCTP_CWND_MONITOR
3394 		int old_cwnd = net->cwnd;
3395 
3396 #endif
3397 		/* need real RTT for this calc */
3398 		rtt = ((net->lastsa >> 2) + net->lastsv) >> 1;
3399 		/* get bottle neck bw */
3400 		bottle_bw = ntohl(cp->bottle_bw);
3401 		/* and whats on queue */
3402 		on_queue = ntohl(cp->current_onq);
3403 		/*
3404 		 * adjust the on-queue if our flight is more it could be
3405 		 * that the router has not yet gotten data "in-flight" to it
3406 		 */
3407 		if (on_queue < net->flight_size)
3408 			on_queue = net->flight_size;
3409 
3410 		/* calculate the available space */
3411 		bw_avail = (bottle_bw * rtt) / 1000;
3412 		if (bw_avail > bottle_bw) {
3413 			/*
3414 			 * Cap the growth to no more than the bottle neck.
3415 			 * This can happen as RTT slides up due to queues.
3416 			 * It also means if you have more than a 1 second
3417 			 * RTT with a empty queue you will be limited to the
3418 			 * bottle_bw per second no matter if other points
3419 			 * have 1/2 the RTT and you could get more out...
3420 			 */
3421 			bw_avail = bottle_bw;
3422 		}
3423 		if (on_queue > bw_avail) {
3424 			/*
3425 			 * No room for anything else don't allow anything
3426 			 * else to be "added to the fire".
3427 			 */
3428 			int seg_inflight, seg_onqueue, my_portion;
3429 
3430 			net->partial_bytes_acked = 0;
3431 
3432 			/* how much are we over queue size? */
3433 			incr = on_queue - bw_avail;
3434 			if (stcb->asoc.seen_a_sack_this_pkt) {
3435 				/*
3436 				 * undo any cwnd adjustment that the sack
3437 				 * might have made
3438 				 */
3439 				net->cwnd = net->prev_cwnd;
3440 			}
3441 			/* Now how much of that is mine? */
3442 			seg_inflight = net->flight_size / net->mtu;
3443 			seg_onqueue = on_queue / net->mtu;
3444 			my_portion = (incr * seg_inflight) / seg_onqueue;
3445 
3446 			/* Have I made an adjustment already */
3447 			if (net->cwnd > net->flight_size) {
3448 				/*
3449 				 * for this flight I made an adjustment we
3450 				 * need to decrease the portion by a share
3451 				 * our previous adjustment.
3452 				 */
3453 				int diff_adj;
3454 
3455 				diff_adj = net->cwnd - net->flight_size;
3456 				if (diff_adj > my_portion)
3457 					my_portion = 0;
3458 				else
3459 					my_portion -= diff_adj;
3460 			}
3461 			/*
3462 			 * back down to the previous cwnd (assume we have
3463 			 * had a sack before this packet). minus what ever
3464 			 * portion of the overage is my fault.
3465 			 */
3466 			net->cwnd -= my_portion;
3467 
3468 			/* we will NOT back down more than 1 MTU */
3469 			if (net->cwnd <= net->mtu) {
3470 				net->cwnd = net->mtu;
3471 			}
3472 			/* force into CA */
3473 			net->ssthresh = net->cwnd - 1;
3474 		} else {
3475 			/*
3476 			 * Take 1/4 of the space left or max burst up ..
3477 			 * whichever is less.
3478 			 */
3479 			incr = min((bw_avail - on_queue) >> 2,
3480 			    (int)stcb->asoc.max_burst * (int)net->mtu);
3481 			net->cwnd += incr;
3482 		}
3483 		if (net->cwnd > bw_avail) {
3484 			/* We can't exceed the pipe size */
3485 			net->cwnd = bw_avail;
3486 		}
3487 		if (net->cwnd < net->mtu) {
3488 			/* We always have 1 MTU */
3489 			net->cwnd = net->mtu;
3490 		}
3491 #ifdef SCTP_CWND_MONITOR
3492 		if (net->cwnd - old_cwnd != 0) {
3493 			/* log only changes */
3494 			sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd),
3495 			    SCTP_CWND_LOG_FROM_SAT);
3496 		}
3497 #endif
3498 	}
3499 }
3500 
3501 extern int sctp_strict_init;
3502 extern int sctp_abort_if_one_2_one_hits_limit;
3503 
3504 /*
3505  * handles all control chunks in a packet inputs: - m: mbuf chain, assumed to
3506  * still contain IP/SCTP header - stcb: is the tcb found for this packet -
3507  * offset: offset into the mbuf chain to first chunkhdr - length: is the
3508  * length of the complete packet outputs: - length: modified to remaining
3509  * length after control processing - netp: modified to new sctp_nets after
3510  * cookie-echo processing - return NULL to discard the packet (ie. no asoc,
3511  * bad packet,...) otherwise return the tcb for this packet
3512  */
3513 static struct sctp_tcb *
3514 sctp_process_control(struct mbuf *m, int iphlen, int *offset, int length,
3515     struct sctphdr *sh, struct sctp_chunkhdr *ch, struct sctp_inpcb *inp,
3516     struct sctp_tcb *stcb, struct sctp_nets **netp, int *fwd_tsn_seen)
3517 {
3518 	struct sctp_association *asoc;
3519 	uint32_t vtag_in;
3520 	int num_chunks = 0;	/* number of control chunks processed */
3521 	int chk_length;
3522 	int ret;
3523 
3524 	/*
3525 	 * How big should this be, and should it be alloc'd? Lets try the
3526 	 * d-mtu-ceiling for now (2k) and that should hopefully work ...
3527 	 * until we get into jumbo grams and such..
3528 	 */
3529 	uint8_t chunk_buf[SCTP_CHUNK_BUFFER_SIZE];
3530 	struct sctp_tcb *locked_tcb = stcb;
3531 	int got_auth = 0;
3532 	uint32_t auth_offset = 0, auth_len = 0;
3533 	int auth_skipped = 0;
3534 
3535 #ifdef SCTP_DEBUG
3536 	if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
3537 		printf("sctp_process_control: iphlen=%u, offset=%u, length=%u stcb:%p\n",
3538 		    iphlen, *offset, length, stcb);
3539 	}
3540 #endif				/* SCTP_DEBUG */
3541 
3542 	/* validate chunk header length... */
3543 	if (ntohs(ch->chunk_length) < sizeof(*ch)) {
3544 		return (NULL);
3545 	}
3546 	/*
3547 	 * validate the verification tag
3548 	 */
3549 	vtag_in = ntohl(sh->v_tag);
3550 
3551 	if (locked_tcb) {
3552 		SCTP_TCB_LOCK_ASSERT(locked_tcb);
3553 	}
3554 	if (ch->chunk_type == SCTP_INITIATION) {
3555 		if (vtag_in != 0) {
3556 			/* protocol error- silently discard... */
3557 			SCTP_STAT_INCR(sctps_badvtag);
3558 			if (locked_tcb)
3559 				SCTP_TCB_UNLOCK(locked_tcb);
3560 			return (NULL);
3561 		}
3562 	} else if (ch->chunk_type != SCTP_COOKIE_ECHO) {
3563 		/*
3564 		 * If there is no stcb, skip the AUTH chunk and process
3565 		 * later after a stcb is found (to validate the lookup was
3566 		 * valid.
3567 		 */
3568 		if ((ch->chunk_type == SCTP_AUTHENTICATION) &&
3569 		    (stcb == NULL) && !sctp_auth_disable) {
3570 			/* save this chunk for later processing */
3571 			auth_skipped = 1;
3572 			auth_offset = *offset;
3573 			auth_len = ntohs(ch->chunk_length);
3574 
3575 			/* (temporarily) move past this chunk */
3576 			*offset += SCTP_SIZE32(auth_len);
3577 			if (*offset >= length) {
3578 				/* no more data left in the mbuf chain */
3579 				*offset = length;
3580 				return (NULL);
3581 			}
3582 			ch = (struct sctp_chunkhdr *)sctp_m_getptr(m, *offset,
3583 			    sizeof(struct sctp_chunkhdr), chunk_buf);
3584 		}
3585 		if (ch->chunk_type == SCTP_COOKIE_ECHO) {
3586 			goto process_control_chunks;
3587 		}
3588 		/*
3589 		 * first check if it's an ASCONF with an unknown src addr we
3590 		 * need to look inside to find the association
3591 		 */
3592 		if (ch->chunk_type == SCTP_ASCONF && stcb == NULL) {
3593 			/* inp's refcount may be reduced */
3594 			SCTP_INP_INCR_REF(inp);
3595 
3596 			stcb = sctp_findassociation_ep_asconf(m, iphlen,
3597 			    *offset, sh, &inp, netp);
3598 			if (stcb == NULL) {
3599 				/*
3600 				 * reduce inp's refcount if not reduced in
3601 				 * sctp_findassociation_ep_asconf().
3602 				 */
3603 				SCTP_INP_DECR_REF(inp);
3604 			}
3605 			/* now go back and verify any auth chunk to be sure */
3606 			if (auth_skipped && (stcb != NULL)) {
3607 				struct sctp_auth_chunk *auth;
3608 
3609 				auth = (struct sctp_auth_chunk *)
3610 				    sctp_m_getptr(m, auth_offset,
3611 				    auth_len, chunk_buf);
3612 				got_auth = 1;
3613 				auth_skipped = 0;
3614 				if (sctp_handle_auth(stcb, auth, m,
3615 				    auth_offset)) {
3616 					/* auth HMAC failed so dump it */
3617 					*offset = length;
3618 					return (NULL);
3619 				} else {
3620 					/* remaining chunks are HMAC checked */
3621 					stcb->asoc.authenticated = 1;
3622 				}
3623 			}
3624 		}
3625 		if (stcb == NULL) {
3626 			/* no association, so it's out of the blue... */
3627 			sctp_handle_ootb(m, iphlen, *offset, sh, inp, NULL);
3628 			*offset = length;
3629 			if (locked_tcb)
3630 				SCTP_TCB_UNLOCK(locked_tcb);
3631 			return (NULL);
3632 		}
3633 		asoc = &stcb->asoc;
3634 		/* ABORT and SHUTDOWN can use either v_tag... */
3635 		if ((ch->chunk_type == SCTP_ABORT_ASSOCIATION) ||
3636 		    (ch->chunk_type == SCTP_SHUTDOWN_COMPLETE) ||
3637 		    (ch->chunk_type == SCTP_PACKET_DROPPED)) {
3638 			if ((vtag_in == asoc->my_vtag) ||
3639 			    ((ch->chunk_flags & SCTP_HAD_NO_TCB) &&
3640 			    (vtag_in == asoc->peer_vtag))) {
3641 				/* this is valid */
3642 			} else {
3643 				/* drop this packet... */
3644 				SCTP_STAT_INCR(sctps_badvtag);
3645 				if (locked_tcb)
3646 					SCTP_TCB_UNLOCK(locked_tcb);
3647 				return (NULL);
3648 			}
3649 		} else if (ch->chunk_type == SCTP_SHUTDOWN_ACK) {
3650 			if (vtag_in != asoc->my_vtag) {
3651 				/*
3652 				 * this could be a stale SHUTDOWN-ACK or the
3653 				 * peer never got the SHUTDOWN-COMPLETE and
3654 				 * is still hung; we have started a new asoc
3655 				 * but it won't complete until the shutdown
3656 				 * is completed
3657 				 */
3658 				if (locked_tcb)
3659 					SCTP_TCB_UNLOCK(locked_tcb);
3660 				sctp_handle_ootb(m, iphlen, *offset, sh, inp,
3661 				    NULL);
3662 				return (NULL);
3663 			}
3664 		} else {
3665 			/* for all other chunks, vtag must match */
3666 			if (vtag_in != asoc->my_vtag) {
3667 				/* invalid vtag... */
3668 #ifdef SCTP_DEBUG
3669 				if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
3670 					printf("invalid vtag: %xh, expect %xh\n", vtag_in, asoc->my_vtag);
3671 				}
3672 #endif				/* SCTP_DEBUG */
3673 				SCTP_STAT_INCR(sctps_badvtag);
3674 				if (locked_tcb)
3675 					SCTP_TCB_UNLOCK(locked_tcb);
3676 				*offset = length;
3677 				return (NULL);
3678 			}
3679 		}
3680 	}			/* end if !SCTP_COOKIE_ECHO */
3681 	/*
3682 	 * process all control chunks...
3683 	 */
3684 	if (((ch->chunk_type == SCTP_SELECTIVE_ACK) ||
3685 	    (ch->chunk_type == SCTP_HEARTBEAT_REQUEST)) &&
3686 	    (SCTP_GET_STATE(&stcb->asoc) == SCTP_STATE_COOKIE_ECHOED)) {
3687 		/* implied cookie-ack.. we must have lost the ack */
3688 		stcb->asoc.overall_error_count = 0;
3689 		sctp_handle_cookie_ack((struct sctp_cookie_ack_chunk *)ch, stcb,
3690 		    *netp);
3691 	}
3692 process_control_chunks:
3693 
3694 	while (IS_SCTP_CONTROL(ch)) {
3695 		/* validate chunk length */
3696 		chk_length = ntohs(ch->chunk_length);
3697 #ifdef SCTP_DEBUG
3698 		if (sctp_debug_on & SCTP_DEBUG_INPUT2) {
3699 			printf("sctp_process_control: processing a chunk type=%u, len=%u\n",
3700 			    ch->chunk_type, chk_length);
3701 		}
3702 #endif				/* SCTP_DEBUG */
3703 		if ((size_t)chk_length < sizeof(*ch) ||
3704 		    (*offset + chk_length) > length) {
3705 			*offset = length;
3706 			if (locked_tcb)
3707 				SCTP_TCB_UNLOCK(locked_tcb);
3708 			return (NULL);
3709 		}
3710 		SCTP_STAT_INCR_COUNTER64(sctps_incontrolchunks);
3711 		/*
3712 		 * INIT-ACK only gets the init ack "header" portion only
3713 		 * because we don't have to process the peer's COOKIE. All
3714 		 * others get a complete chunk.
3715 		 */
3716 		if (ch->chunk_type == SCTP_INITIATION_ACK) {
3717 			/* get an init-ack chunk */
3718 			ch = (struct sctp_chunkhdr *)sctp_m_getptr(m, *offset,
3719 			    sizeof(struct sctp_init_ack_chunk), chunk_buf);
3720 			if (ch == NULL) {
3721 				*offset = length;
3722 				if (locked_tcb)
3723 					SCTP_TCB_UNLOCK(locked_tcb);
3724 				return (NULL);
3725 			}
3726 		} else {
3727 			/* get a complete chunk... */
3728 			if ((size_t)chk_length > sizeof(chunk_buf)) {
3729 				struct mbuf *oper;
3730 				struct sctp_paramhdr *phdr;
3731 
3732 				oper = NULL;
3733 				oper = sctp_get_mbuf_for_msg(sizeof(struct sctp_paramhdr),
3734 				    0, M_DONTWAIT, 1, MT_DATA);
3735 				if (oper) {
3736 					/* pre-reserve some space */
3737 					SCTP_BUF_RESV_UF(oper, sizeof(struct sctp_chunkhdr));
3738 					SCTP_BUF_LEN(oper) = sizeof(struct sctp_paramhdr);
3739 					phdr = mtod(oper, struct sctp_paramhdr *);
3740 					phdr->param_type = htons(SCTP_CAUSE_OUT_OF_RESC);
3741 					phdr->param_length = htons(sizeof(struct sctp_paramhdr));
3742 					sctp_queue_op_err(stcb, oper);
3743 				}
3744 				if (locked_tcb)
3745 					SCTP_TCB_UNLOCK(locked_tcb);
3746 				return (NULL);
3747 			}
3748 			ch = (struct sctp_chunkhdr *)sctp_m_getptr(m, *offset,
3749 			    chk_length, chunk_buf);
3750 			if (ch == NULL) {
3751 				printf("sctp_process_control: Can't get the all data....\n");
3752 				*offset = length;
3753 				if (locked_tcb)
3754 					SCTP_TCB_UNLOCK(locked_tcb);
3755 				return (NULL);
3756 			}
3757 		}
3758 		num_chunks++;
3759 		/* Save off the last place we got a control from */
3760 		if (stcb != NULL) {
3761 			if ((*netp != NULL) || (ch->chunk_type == SCTP_ASCONF)) {
3762 				/*
3763 				 * allow last_control to be NULL if
3764 				 * ASCONF... ASCONF processing will find the
3765 				 * right net later
3766 				 */
3767 				stcb->asoc.last_control_chunk_from = *netp;
3768 			}
3769 		}
3770 #ifdef SCTP_AUDITING_ENABLED
3771 		sctp_audit_log(0xB0, ch->chunk_type);
3772 #endif
3773 
3774 		/* check to see if this chunk required auth, but isn't */
3775 		if ((stcb != NULL) && !sctp_auth_disable &&
3776 		    sctp_auth_is_required_chunk(ch->chunk_type,
3777 		    stcb->asoc.local_auth_chunks) &&
3778 		    !stcb->asoc.authenticated) {
3779 			/* "silently" ignore */
3780 			SCTP_STAT_INCR(sctps_recvauthmissing);
3781 			goto next_chunk;
3782 		}
3783 		switch (ch->chunk_type) {
3784 		case SCTP_INITIATION:
3785 			/* must be first and only chunk */
3786 #ifdef SCTP_DEBUG
3787 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
3788 				printf("SCTP_INIT\n");
3789 			}
3790 #endif				/* SCTP_DEBUG */
3791 			if (inp->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) {
3792 				/* We are not interested anymore? */
3793 				if ((stcb) && (stcb->asoc.total_output_queue_size)) {
3794 					/*
3795 					 * collision case where we are
3796 					 * sending to them too
3797 					 */
3798 					;
3799 				} else {
3800 					if (locked_tcb)
3801 						SCTP_TCB_UNLOCK(locked_tcb);
3802 					*offset = length;
3803 					return (NULL);
3804 				}
3805 			}
3806 			if ((num_chunks > 1) ||
3807 			    (sctp_strict_init && (length - *offset > SCTP_SIZE32(chk_length)))) {
3808 				*offset = length;
3809 				if (locked_tcb)
3810 					SCTP_TCB_UNLOCK(locked_tcb);
3811 				return (NULL);
3812 			}
3813 			if ((stcb != NULL) &&
3814 			    (SCTP_GET_STATE(&stcb->asoc) ==
3815 			    SCTP_STATE_SHUTDOWN_ACK_SENT)) {
3816 				sctp_send_shutdown_ack(stcb,
3817 				    stcb->asoc.primary_destination);
3818 				*offset = length;
3819 				sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_CONTROL_PROC);
3820 				if (locked_tcb)
3821 					SCTP_TCB_UNLOCK(locked_tcb);
3822 				return (NULL);
3823 			}
3824 			sctp_handle_init(m, iphlen, *offset, sh,
3825 			    (struct sctp_init_chunk *)ch, inp, stcb, *netp);
3826 			*offset = length;
3827 			if (locked_tcb)
3828 				SCTP_TCB_UNLOCK(locked_tcb);
3829 			return (NULL);
3830 			break;
3831 		case SCTP_INITIATION_ACK:
3832 			/* must be first and only chunk */
3833 #ifdef SCTP_DEBUG
3834 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
3835 				printf("SCTP_INIT-ACK\n");
3836 			}
3837 #endif				/* SCTP_DEBUG */
3838 			if (inp->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) {
3839 				/* We are not interested anymore */
3840 				if ((stcb) && (stcb->asoc.total_output_queue_size)) {
3841 					;
3842 				} else {
3843 					if (locked_tcb)
3844 						SCTP_TCB_UNLOCK(locked_tcb);
3845 					*offset = length;
3846 					if (stcb) {
3847 						sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC, SCTP_FROM_SCTP_INPUT + SCTP_LOC_26);
3848 					}
3849 					return (NULL);
3850 				}
3851 			}
3852 			if ((num_chunks > 1) ||
3853 			    (sctp_strict_init && (length - *offset > SCTP_SIZE32(chk_length)))) {
3854 				*offset = length;
3855 				if (locked_tcb)
3856 					SCTP_TCB_UNLOCK(locked_tcb);
3857 				return (NULL);
3858 			}
3859 			ret = sctp_handle_init_ack(m, iphlen, *offset, sh,
3860 			    (struct sctp_init_ack_chunk *)ch, stcb, *netp);
3861 			/*
3862 			 * Special case, I must call the output routine to
3863 			 * get the cookie echoed
3864 			 */
3865 			if ((stcb) && ret == 0)
3866 				sctp_chunk_output(stcb->sctp_ep, stcb, SCTP_OUTPUT_FROM_CONTROL_PROC);
3867 			*offset = length;
3868 			if (locked_tcb)
3869 				SCTP_TCB_UNLOCK(locked_tcb);
3870 			return (NULL);
3871 			break;
3872 		case SCTP_SELECTIVE_ACK:
3873 #ifdef SCTP_DEBUG
3874 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
3875 				printf("SCTP_SACK\n");
3876 			}
3877 #endif				/* SCTP_DEBUG */
3878 			SCTP_STAT_INCR(sctps_recvsacks);
3879 			{
3880 				struct sctp_sack_chunk *sack;
3881 				int abort_now = 0;
3882 				uint32_t a_rwnd, cum_ack;
3883 				uint16_t num_seg;
3884 				int nonce_sum_flag;
3885 
3886 				sack = (struct sctp_sack_chunk *)ch;
3887 
3888 				nonce_sum_flag = ch->chunk_flags & SCTP_SACK_NONCE_SUM;
3889 				cum_ack = ntohl(sack->sack.cum_tsn_ack);
3890 				num_seg = ntohs(sack->sack.num_gap_ack_blks);
3891 				a_rwnd = (uint32_t) ntohl(sack->sack.a_rwnd);
3892 				stcb->asoc.seen_a_sack_this_pkt = 1;
3893 				if ((stcb->asoc.pr_sctp_cnt == 0) &&
3894 				    (num_seg == 0) &&
3895 				    ((compare_with_wrap(cum_ack, stcb->asoc.last_acked_seq, MAX_TSN)) ||
3896 				    (cum_ack == stcb->asoc.last_acked_seq)) &&
3897 				    (stcb->asoc.saw_sack_with_frags == 0) &&
3898 				    (!TAILQ_EMPTY(&stcb->asoc.sent_queue))
3899 				    ) {
3900 					/*
3901 					 * We have a SIMPLE sack having no
3902 					 * prior segments and data on sent
3903 					 * queue to be acked.. Use the
3904 					 * faster path sack processing. We
3905 					 * also allow window update sacks
3906 					 * with no missing segments to go
3907 					 * this way too.
3908 					 */
3909 					sctp_express_handle_sack(stcb, cum_ack, a_rwnd, nonce_sum_flag, &abort_now);
3910 				} else {
3911 					sctp_handle_sack(sack, stcb, *netp, &abort_now);
3912 				}
3913 				if (abort_now) {
3914 					/* ABORT signal from sack processing */
3915 					*offset = length;
3916 					return (NULL);
3917 				}
3918 			}
3919 			break;
3920 		case SCTP_HEARTBEAT_REQUEST:
3921 #ifdef SCTP_DEBUG
3922 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
3923 				printf("SCTP_HEARTBEAT\n");
3924 			}
3925 #endif				/* SCTP_DEBUG */
3926 			SCTP_STAT_INCR(sctps_recvheartbeat);
3927 			sctp_send_heartbeat_ack(stcb, m, *offset, chk_length,
3928 			    *netp);
3929 
3930 			/* He's alive so give him credit */
3931 			stcb->asoc.overall_error_count = 0;
3932 			break;
3933 		case SCTP_HEARTBEAT_ACK:
3934 #ifdef SCTP_DEBUG
3935 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
3936 				printf("SCTP_HEARTBEAT-ACK\n");
3937 			}
3938 #endif				/* SCTP_DEBUG */
3939 
3940 			/* He's alive so give him credit */
3941 			stcb->asoc.overall_error_count = 0;
3942 			SCTP_STAT_INCR(sctps_recvheartbeatack);
3943 			sctp_handle_heartbeat_ack((struct sctp_heartbeat_chunk *)ch,
3944 			    stcb, *netp);
3945 			break;
3946 		case SCTP_ABORT_ASSOCIATION:
3947 #ifdef SCTP_DEBUG
3948 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
3949 				printf("SCTP_ABORT\n");
3950 			}
3951 #endif				/* SCTP_DEBUG */
3952 			sctp_handle_abort((struct sctp_abort_chunk *)ch,
3953 			    stcb, *netp);
3954 			*offset = length;
3955 			return (NULL);
3956 			break;
3957 		case SCTP_SHUTDOWN:
3958 #ifdef SCTP_DEBUG
3959 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
3960 				printf("SCTP_SHUTDOWN\n");
3961 			}
3962 #endif				/* SCTP_DEBUG */
3963 			{
3964 				int abort_flag = 0;
3965 
3966 				sctp_handle_shutdown((struct sctp_shutdown_chunk *)ch,
3967 				    stcb, *netp, &abort_flag);
3968 				if (abort_flag) {
3969 					*offset = length;
3970 					return (NULL);
3971 				}
3972 			}
3973 			break;
3974 		case SCTP_SHUTDOWN_ACK:
3975 #ifdef SCTP_DEBUG
3976 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
3977 				printf("SCTP_SHUTDOWN-ACK\n");
3978 			}
3979 #endif				/* SCTP_DEBUG */
3980 			sctp_handle_shutdown_ack((struct sctp_shutdown_ack_chunk *)ch, stcb, *netp);
3981 			*offset = length;
3982 			return (NULL);
3983 			break;
3984 		case SCTP_OPERATION_ERROR:
3985 #ifdef SCTP_DEBUG
3986 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
3987 				printf("SCTP_OP-ERR\n");
3988 			}
3989 #endif				/* SCTP_DEBUG */
3990 			if (sctp_handle_error(ch, stcb, *netp) < 0) {
3991 				*offset = length;
3992 				return (NULL);
3993 			}
3994 			break;
3995 		case SCTP_COOKIE_ECHO:
3996 #ifdef SCTP_DEBUG
3997 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
3998 				printf("SCTP_COOKIE-ECHO stcb is %p\n", stcb);
3999 			}
4000 #endif				/* SCTP_DEBUG */
4001 			if ((stcb) && (stcb->asoc.total_output_queue_size)) {
4002 				;
4003 			} else {
4004 				if ((inp->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) &&
4005 				    (stcb == NULL)) {
4006 					/* We are not interested anymore */
4007 					*offset = length;
4008 					return (NULL);
4009 				}
4010 			}
4011 			/*
4012 			 * First are we accepting? We do this again here
4013 			 * since it is possible that a previous endpoint WAS
4014 			 * listening responded to a INIT-ACK and then
4015 			 * closed. We opened and bound.. and are now no
4016 			 * longer listening.
4017 			 */
4018 			if (inp->sctp_socket->so_qlimit == 0) {
4019 				if ((stcb) && (inp->sctp_flags & SCTP_PCB_FLAGS_IN_TCPPOOL)) {
4020 					/*
4021 					 * special case, is this a retran'd
4022 					 * COOKIE-ECHO or a restarting assoc
4023 					 * that is a peeled off or
4024 					 * one-to-one style socket.
4025 					 */
4026 					goto process_cookie_anyway;
4027 				}
4028 				sctp_abort_association(inp, stcb, m, iphlen, sh,
4029 				    NULL);
4030 				*offset = length;
4031 				return (NULL);
4032 			} else if (inp->sctp_socket->so_qlimit) {
4033 				/* we are accepting so check limits like TCP */
4034 				if (inp->sctp_socket->so_qlen >
4035 				    inp->sctp_socket->so_qlimit) {
4036 					/* no space */
4037 					struct mbuf *oper;
4038 					struct sctp_paramhdr *phdr;
4039 
4040 					if (sctp_abort_if_one_2_one_hits_limit) {
4041 						oper = NULL;
4042 						oper = sctp_get_mbuf_for_msg(sizeof(struct sctp_paramhdr),
4043 						    0, M_DONTWAIT, 1, MT_DATA);
4044 						if (oper) {
4045 							SCTP_BUF_LEN(oper) =
4046 							    sizeof(struct sctp_paramhdr);
4047 							phdr = mtod(oper,
4048 							    struct sctp_paramhdr *);
4049 							phdr->param_type =
4050 							    htons(SCTP_CAUSE_OUT_OF_RESC);
4051 							phdr->param_length =
4052 							    htons(sizeof(struct sctp_paramhdr));
4053 						}
4054 						sctp_abort_association(inp, stcb, m,
4055 						    iphlen, sh, oper);
4056 					}
4057 					*offset = length;
4058 					return (NULL);
4059 				}
4060 			}
4061 	process_cookie_anyway:
4062 			{
4063 				struct mbuf *ret_buf;
4064 				struct sctp_inpcb *linp;
4065 
4066 				if (stcb)
4067 					linp = NULL;
4068 				else
4069 					linp = inp;
4070 
4071 				if (linp)
4072 					SCTP_ASOC_CREATE_LOCK(linp);
4073 				ret_buf =
4074 				    sctp_handle_cookie_echo(m, iphlen,
4075 				    *offset, sh,
4076 				    (struct sctp_cookie_echo_chunk *)ch,
4077 				    &inp, &stcb, netp,
4078 				    auth_skipped,
4079 				    auth_offset,
4080 				    auth_len,
4081 				    &locked_tcb);
4082 				if (linp)
4083 					SCTP_ASOC_CREATE_UNLOCK(linp);
4084 				if (ret_buf == NULL) {
4085 					if (locked_tcb) {
4086 						SCTP_TCB_UNLOCK(locked_tcb);
4087 					}
4088 #ifdef SCTP_DEBUG
4089 					if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
4090 						printf("GAK, null buffer\n");
4091 					}
4092 #endif				/* SCTP_DEBUG */
4093 					auth_skipped = 0;
4094 					*offset = length;
4095 					return (NULL);
4096 				}
4097 				/* if AUTH skipped, see if it verified... */
4098 				if (auth_skipped) {
4099 					got_auth = 1;
4100 					auth_skipped = 0;
4101 				}
4102 				if (!TAILQ_EMPTY(&stcb->asoc.sent_queue)) {
4103 					/*
4104 					 * Restart the timer if we have
4105 					 * pending data
4106 					 */
4107 					struct sctp_tmit_chunk *chk;
4108 
4109 					chk = TAILQ_FIRST(&stcb->asoc.sent_queue);
4110 					if (chk) {
4111 						sctp_timer_start(SCTP_TIMER_TYPE_SEND,
4112 						    stcb->sctp_ep, stcb,
4113 						    chk->whoTo);
4114 					}
4115 				}
4116 			}
4117 			break;
4118 		case SCTP_COOKIE_ACK:
4119 #ifdef SCTP_DEBUG
4120 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
4121 				printf("SCTP_COOKIE-ACK\n");
4122 			}
4123 #endif				/* SCTP_DEBUG */
4124 
4125 			if (inp->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) {
4126 				/* We are not interested anymore */
4127 				if ((stcb) && (stcb->asoc.total_output_queue_size)) {
4128 					;
4129 				} else {
4130 					sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC, SCTP_FROM_SCTP_INPUT + SCTP_LOC_27);
4131 					*offset = length;
4132 					return (NULL);
4133 				}
4134 			}
4135 			/* He's alive so give him credit */
4136 			stcb->asoc.overall_error_count = 0;
4137 			sctp_handle_cookie_ack((struct sctp_cookie_ack_chunk *)ch, stcb, *netp);
4138 			break;
4139 		case SCTP_ECN_ECHO:
4140 #ifdef SCTP_DEBUG
4141 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
4142 				printf("SCTP_ECN-ECHO\n");
4143 			}
4144 #endif				/* SCTP_DEBUG */
4145 			/* He's alive so give him credit */
4146 			stcb->asoc.overall_error_count = 0;
4147 			sctp_handle_ecn_echo((struct sctp_ecne_chunk *)ch,
4148 			    stcb);
4149 			break;
4150 		case SCTP_ECN_CWR:
4151 #ifdef SCTP_DEBUG
4152 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
4153 				printf("SCTP_ECN-CWR\n");
4154 			}
4155 #endif				/* SCTP_DEBUG */
4156 			/* He's alive so give him credit */
4157 			stcb->asoc.overall_error_count = 0;
4158 
4159 			sctp_handle_ecn_cwr((struct sctp_cwr_chunk *)ch, stcb);
4160 			break;
4161 		case SCTP_SHUTDOWN_COMPLETE:
4162 #ifdef SCTP_DEBUG
4163 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
4164 				printf("SCTP_SHUTDOWN-COMPLETE\n");
4165 			}
4166 #endif				/* SCTP_DEBUG */
4167 			/* must be first and only chunk */
4168 			if ((num_chunks > 1) ||
4169 			    (length - *offset > SCTP_SIZE32(chk_length))) {
4170 				*offset = length;
4171 				if (locked_tcb)
4172 					SCTP_TCB_UNLOCK(locked_tcb);
4173 
4174 				return (NULL);
4175 			}
4176 			sctp_handle_shutdown_complete((struct sctp_shutdown_complete_chunk *)ch,
4177 			    stcb, *netp);
4178 			*offset = length;
4179 			return (NULL);
4180 			break;
4181 		case SCTP_ASCONF:
4182 #ifdef SCTP_DEBUG
4183 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
4184 				printf("SCTP_ASCONF\n");
4185 			}
4186 #endif				/* SCTP_DEBUG */
4187 			/* He's alive so give him credit */
4188 			stcb->asoc.overall_error_count = 0;
4189 
4190 			sctp_handle_asconf(m, *offset,
4191 			    (struct sctp_asconf_chunk *)ch, stcb);
4192 			break;
4193 		case SCTP_ASCONF_ACK:
4194 #ifdef SCTP_DEBUG
4195 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
4196 				printf("SCTP_ASCONF-ACK\n");
4197 			}
4198 #endif				/* SCTP_DEBUG */
4199 			/* He's alive so give him credit */
4200 			stcb->asoc.overall_error_count = 0;
4201 
4202 			sctp_handle_asconf_ack(m, *offset,
4203 			    (struct sctp_asconf_ack_chunk *)ch, stcb, *netp);
4204 			break;
4205 		case SCTP_FORWARD_CUM_TSN:
4206 #ifdef SCTP_DEBUG
4207 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
4208 				printf("SCTP_FWD-TSN\n");
4209 			}
4210 #endif				/* SCTP_DEBUG */
4211 			/* He's alive so give him credit */
4212 			{
4213 				int abort_flag = 0;
4214 
4215 				stcb->asoc.overall_error_count = 0;
4216 				*fwd_tsn_seen = 1;
4217 				if (inp->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) {
4218 					/* We are not interested anymore */
4219 					sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC, SCTP_FROM_SCTP_INPUT + SCTP_LOC_28);
4220 					*offset = length;
4221 					return (NULL);
4222 				}
4223 				sctp_handle_forward_tsn(stcb,
4224 				    (struct sctp_forward_tsn_chunk *)ch, &abort_flag);
4225 				if (abort_flag) {
4226 					*offset = length;
4227 					return (NULL);
4228 				} else {
4229 					stcb->asoc.overall_error_count = 0;
4230 				}
4231 
4232 			}
4233 			break;
4234 		case SCTP_STREAM_RESET:
4235 #ifdef SCTP_DEBUG
4236 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
4237 				printf("SCTP_STREAM_RESET\n");
4238 			}
4239 #endif				/* SCTP_DEBUG */
4240 			ch = (struct sctp_chunkhdr *)sctp_m_getptr(m, *offset,
4241 			    chk_length, chunk_buf);
4242 			if (inp->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) {
4243 				/* We are not interested anymore */
4244 				sctp_free_assoc(inp, stcb, SCTP_NORMAL_PROC, SCTP_FROM_SCTP_INPUT + SCTP_LOC_29);
4245 				*offset = length;
4246 				return (NULL);
4247 			}
4248 			if (stcb->asoc.peer_supports_strreset == 0) {
4249 				/*
4250 				 * hmm, peer should have announced this, but
4251 				 * we will turn it on since he is sending us
4252 				 * a stream reset.
4253 				 */
4254 				stcb->asoc.peer_supports_strreset = 1;
4255 			}
4256 			if (sctp_handle_stream_reset(stcb, (struct sctp_stream_reset_out_req *)ch)) {
4257 				/* stop processing */
4258 				*offset = length;
4259 				return (NULL);
4260 			}
4261 			break;
4262 		case SCTP_PACKET_DROPPED:
4263 #ifdef SCTP_DEBUG
4264 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
4265 				printf("SCTP_PACKET_DROPPED\n");
4266 			}
4267 #endif				/* SCTP_DEBUG */
4268 			/* re-get it all please */
4269 			ch = (struct sctp_chunkhdr *)sctp_m_getptr(m, *offset,
4270 			    chk_length, chunk_buf);
4271 
4272 			sctp_handle_packet_dropped((struct sctp_pktdrop_chunk *)ch,
4273 			    stcb, *netp);
4274 
4275 			break;
4276 
4277 		case SCTP_AUTHENTICATION:
4278 #ifdef SCTP_DEBUG
4279 			if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
4280 				printf("SCTP_AUTHENTICATION\n");
4281 			}
4282 #endif				/* SCTP_DEBUG */
4283 			if (sctp_auth_disable)
4284 				goto unknown_chunk;
4285 
4286 			if (stcb == NULL) {
4287 				/* save the first AUTH for later processing */
4288 				if (auth_skipped == 0) {
4289 					auth_offset = *offset;
4290 					auth_len = chk_length;
4291 					auth_skipped = 1;
4292 				}
4293 				/* skip this chunk (temporarily) */
4294 				goto next_chunk;
4295 			}
4296 			if (got_auth == 1) {
4297 				/* skip this chunk... it's already auth'd */
4298 				goto next_chunk;
4299 			}
4300 			ch = (struct sctp_chunkhdr *)sctp_m_getptr(m, *offset,
4301 			    chk_length, chunk_buf);
4302 			got_auth = 1;
4303 			if (sctp_handle_auth(stcb, (struct sctp_auth_chunk *)ch,
4304 			    m, *offset)) {
4305 				/* auth HMAC failed so dump the packet */
4306 				*offset = length;
4307 				return (stcb);
4308 			} else {
4309 				/* remaining chunks are HMAC checked */
4310 				stcb->asoc.authenticated = 1;
4311 			}
4312 			break;
4313 
4314 		default:
4315 	unknown_chunk:
4316 			/* it's an unknown chunk! */
4317 			if ((ch->chunk_type & 0x40) && (stcb != NULL)) {
4318 				struct mbuf *mm;
4319 				struct sctp_paramhdr *phd;
4320 
4321 				mm = sctp_get_mbuf_for_msg(sizeof(struct sctp_paramhdr),
4322 				    0, M_DONTWAIT, 1, MT_DATA);
4323 				if (mm) {
4324 					phd = mtod(mm, struct sctp_paramhdr *);
4325 					/*
4326 					 * We cheat and use param type since
4327 					 * we did not bother to define a
4328 					 * error cause struct. They are the
4329 					 * same basic format with different
4330 					 * names.
4331 					 */
4332 					phd->param_type = htons(SCTP_CAUSE_UNRECOG_CHUNK);
4333 					phd->param_length = htons(chk_length + sizeof(*phd));
4334 					SCTP_BUF_LEN(mm) = sizeof(*phd);
4335 					SCTP_BUF_NEXT(mm) = SCTP_M_COPYM(m, *offset, SCTP_SIZE32(chk_length),
4336 					    M_DONTWAIT);
4337 					if (SCTP_BUF_NEXT(mm)) {
4338 						sctp_queue_op_err(stcb, mm);
4339 					} else {
4340 						sctp_m_freem(mm);
4341 					}
4342 				}
4343 			}
4344 			if ((ch->chunk_type & 0x80) == 0) {
4345 				/* discard this packet */
4346 				*offset = length;
4347 				return (stcb);
4348 			}	/* else skip this bad chunk and continue... */
4349 			break;
4350 		}		/* switch (ch->chunk_type) */
4351 
4352 
4353 next_chunk:
4354 		/* get the next chunk */
4355 		*offset += SCTP_SIZE32(chk_length);
4356 		if (*offset >= length) {
4357 			/* no more data left in the mbuf chain */
4358 			break;
4359 		}
4360 		ch = (struct sctp_chunkhdr *)sctp_m_getptr(m, *offset,
4361 		    sizeof(struct sctp_chunkhdr), chunk_buf);
4362 		if (ch == NULL) {
4363 			if (locked_tcb)
4364 				SCTP_TCB_UNLOCK(locked_tcb);
4365 			*offset = length;
4366 			return (NULL);
4367 		}
4368 	}			/* while */
4369 	return (stcb);
4370 }
4371 
4372 
4373 /*
4374  * Process the ECN bits we have something set so we must look to see if it is
4375  * ECN(0) or ECN(1) or CE
4376  */
4377 static __inline void
4378 sctp_process_ecn_marked_a(struct sctp_tcb *stcb, struct sctp_nets *net,
4379     uint8_t ecn_bits)
4380 {
4381 	if ((ecn_bits & SCTP_CE_BITS) == SCTP_CE_BITS) {
4382 		;
4383 	} else if ((ecn_bits & SCTP_ECT1_BIT) == SCTP_ECT1_BIT) {
4384 		/*
4385 		 * we only add to the nonce sum for ECT1, ECT0 does not
4386 		 * change the NS bit (that we have yet to find a way to send
4387 		 * it yet).
4388 		 */
4389 
4390 		/* ECN Nonce stuff */
4391 		stcb->asoc.receiver_nonce_sum++;
4392 		stcb->asoc.receiver_nonce_sum &= SCTP_SACK_NONCE_SUM;
4393 
4394 		/*
4395 		 * Drag up the last_echo point if cumack is larger since we
4396 		 * don't want the point falling way behind by more than
4397 		 * 2^^31 and then having it be incorrect.
4398 		 */
4399 		if (compare_with_wrap(stcb->asoc.cumulative_tsn,
4400 		    stcb->asoc.last_echo_tsn, MAX_TSN)) {
4401 			stcb->asoc.last_echo_tsn = stcb->asoc.cumulative_tsn;
4402 		}
4403 	} else if ((ecn_bits & SCTP_ECT0_BIT) == SCTP_ECT0_BIT) {
4404 		/*
4405 		 * Drag up the last_echo point if cumack is larger since we
4406 		 * don't want the point falling way behind by more than
4407 		 * 2^^31 and then having it be incorrect.
4408 		 */
4409 		if (compare_with_wrap(stcb->asoc.cumulative_tsn,
4410 		    stcb->asoc.last_echo_tsn, MAX_TSN)) {
4411 			stcb->asoc.last_echo_tsn = stcb->asoc.cumulative_tsn;
4412 		}
4413 	}
4414 }
4415 
4416 static __inline void
4417 sctp_process_ecn_marked_b(struct sctp_tcb *stcb, struct sctp_nets *net,
4418     uint32_t high_tsn, uint8_t ecn_bits)
4419 {
4420 	if ((ecn_bits & SCTP_CE_BITS) == SCTP_CE_BITS) {
4421 		/*
4422 		 * we possibly must notify the sender that a congestion
4423 		 * window reduction is in order. We do this by adding a ECNE
4424 		 * chunk to the output chunk queue. The incoming CWR will
4425 		 * remove this chunk.
4426 		 */
4427 		if (compare_with_wrap(high_tsn, stcb->asoc.last_echo_tsn,
4428 		    MAX_TSN)) {
4429 			/* Yep, we need to add a ECNE */
4430 			sctp_send_ecn_echo(stcb, net, high_tsn);
4431 			stcb->asoc.last_echo_tsn = high_tsn;
4432 		}
4433 	}
4434 }
4435 
4436 /*
4437  * common input chunk processing (v4 and v6)
4438  */
4439 int
4440 sctp_common_input_processing(struct mbuf **mm, int iphlen, int offset,
4441     int length, struct sctphdr *sh, struct sctp_chunkhdr *ch,
4442     struct sctp_inpcb *inp, struct sctp_tcb *stcb, struct sctp_nets *net,
4443     uint8_t ecn_bits)
4444 {
4445 	/*
4446 	 * Control chunk processing
4447 	 */
4448 	uint32_t high_tsn;
4449 	int fwd_tsn_seen = 0, data_processed = 0;
4450 	struct mbuf *m = *mm;
4451 	int abort_flag = 0;
4452 	int un_sent;
4453 
4454 	SCTP_STAT_INCR(sctps_recvdatagrams);
4455 #ifdef SCTP_AUDITING_ENABLED
4456 	sctp_audit_log(0xE0, 1);
4457 	sctp_auditing(0, inp, stcb, net);
4458 #endif
4459 
4460 #ifdef SCTP_DEBUG
4461 	if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
4462 		printf("Ok, Common input processing called, m:%p iphlen:%d offset:%d\n",
4463 		    m, iphlen, offset);
4464 	}
4465 #endif				/* SCTP_DEBUG */
4466 
4467 	if (stcb) {
4468 		/* always clear this before beginning a packet */
4469 		stcb->asoc.authenticated = 0;
4470 		stcb->asoc.seen_a_sack_this_pkt = 0;
4471 	}
4472 	if (IS_SCTP_CONTROL(ch)) {
4473 		/* process the control portion of the SCTP packet */
4474 		stcb = sctp_process_control(m, iphlen, &offset, length, sh, ch,
4475 		    inp, stcb, &net, &fwd_tsn_seen);
4476 		if (stcb) {
4477 			/*
4478 			 * This covers us if the cookie-echo was there and
4479 			 * it changes our INP.
4480 			 */
4481 			inp = stcb->sctp_ep;
4482 		}
4483 	} else {
4484 		/*
4485 		 * no control chunks, so pre-process DATA chunks (these
4486 		 * checks are taken care of by control processing)
4487 		 */
4488 
4489 		/*
4490 		 * if DATA only packet, and auth is required, then punt...
4491 		 * can't have authenticated without any AUTH (control)
4492 		 * chunks
4493 		 */
4494 		if ((stcb != NULL) && !sctp_auth_disable &&
4495 		    sctp_auth_is_required_chunk(SCTP_DATA,
4496 		    stcb->asoc.local_auth_chunks)) {
4497 			/* "silently" ignore */
4498 			SCTP_STAT_INCR(sctps_recvauthmissing);
4499 			SCTP_TCB_UNLOCK(stcb);
4500 			return (1);
4501 		}
4502 		if (stcb == NULL) {
4503 			/* out of the blue DATA chunk */
4504 			sctp_handle_ootb(m, iphlen, offset, sh, inp, NULL);
4505 			return (1);
4506 		}
4507 		if (stcb->asoc.my_vtag != ntohl(sh->v_tag)) {
4508 			/* v_tag mismatch! */
4509 			SCTP_STAT_INCR(sctps_badvtag);
4510 			SCTP_TCB_UNLOCK(stcb);
4511 			return (1);
4512 		}
4513 	}
4514 
4515 	if (stcb == NULL) {
4516 		/*
4517 		 * no valid TCB for this packet, or we found it's a bad
4518 		 * packet while processing control, or we're done with this
4519 		 * packet (done or skip rest of data), so we drop it...
4520 		 */
4521 		return (1);
4522 	}
4523 	/*
4524 	 * DATA chunk processing
4525 	 */
4526 	/* plow through the data chunks while length > offset */
4527 
4528 	/*
4529 	 * Rest should be DATA only.  Check authentication state if AUTH for
4530 	 * DATA is required.
4531 	 */
4532 	if ((length > offset) && (stcb != NULL) && !sctp_auth_disable &&
4533 	    sctp_auth_is_required_chunk(SCTP_DATA,
4534 	    stcb->asoc.local_auth_chunks) &&
4535 	    !stcb->asoc.authenticated) {
4536 		/* "silently" ignore */
4537 		SCTP_STAT_INCR(sctps_recvauthmissing);
4538 #ifdef SCTP_DEBUG
4539 		if (sctp_debug_on & SCTP_DEBUG_AUTH1)
4540 			printf("Data chunk requires AUTH, skipped\n");
4541 #endif
4542 		goto trigger_send;
4543 	}
4544 	if (length > offset) {
4545 		int retval;
4546 
4547 		/*
4548 		 * First check to make sure our state is correct. We would
4549 		 * not get here unless we really did have a tag, so we don't
4550 		 * abort if this happens, just dump the chunk silently.
4551 		 */
4552 		switch (SCTP_GET_STATE(&stcb->asoc)) {
4553 		case SCTP_STATE_COOKIE_ECHOED:
4554 			/*
4555 			 * we consider data with valid tags in this state
4556 			 * shows us the cookie-ack was lost. Imply it was
4557 			 * there.
4558 			 */
4559 			stcb->asoc.overall_error_count = 0;
4560 			sctp_handle_cookie_ack((struct sctp_cookie_ack_chunk *)ch, stcb, net);
4561 			break;
4562 		case SCTP_STATE_COOKIE_WAIT:
4563 			/*
4564 			 * We consider OOTB any data sent during asoc setup.
4565 			 */
4566 			sctp_handle_ootb(m, iphlen, offset, sh, inp, NULL);
4567 			SCTP_TCB_UNLOCK(stcb);
4568 			return (1);
4569 			break;
4570 		case SCTP_STATE_EMPTY:	/* should not happen */
4571 		case SCTP_STATE_INUSE:	/* should not happen */
4572 		case SCTP_STATE_SHUTDOWN_RECEIVED:	/* This is a peer error */
4573 		case SCTP_STATE_SHUTDOWN_ACK_SENT:
4574 		default:
4575 			SCTP_TCB_UNLOCK(stcb);
4576 			return (1);
4577 			break;
4578 		case SCTP_STATE_OPEN:
4579 		case SCTP_STATE_SHUTDOWN_SENT:
4580 			break;
4581 		}
4582 		/* take care of ECN, part 1. */
4583 		if (stcb->asoc.ecn_allowed &&
4584 		    (ecn_bits & (SCTP_ECT0_BIT | SCTP_ECT1_BIT))) {
4585 			sctp_process_ecn_marked_a(stcb, net, ecn_bits);
4586 		}
4587 		/* plow through the data chunks while length > offset */
4588 		retval = sctp_process_data(mm, iphlen, &offset, length, sh,
4589 		    inp, stcb, net, &high_tsn);
4590 		if (retval == 2) {
4591 			/*
4592 			 * The association aborted, NO UNLOCK needed since
4593 			 * the association is destroyed.
4594 			 */
4595 			return (0);
4596 		}
4597 		data_processed = 1;
4598 		if (retval == 0) {
4599 			/* take care of ecn part 2. */
4600 			if (stcb->asoc.ecn_allowed &&
4601 			    (ecn_bits & (SCTP_ECT0_BIT | SCTP_ECT1_BIT))) {
4602 				sctp_process_ecn_marked_b(stcb, net, high_tsn,
4603 				    ecn_bits);
4604 			}
4605 		}
4606 		/*
4607 		 * Anything important needs to have been m_copy'ed in
4608 		 * process_data
4609 		 */
4610 	}
4611 	if ((data_processed == 0) && (fwd_tsn_seen)) {
4612 		int was_a_gap = 0;
4613 
4614 		if (compare_with_wrap(stcb->asoc.highest_tsn_inside_map,
4615 		    stcb->asoc.cumulative_tsn, MAX_TSN)) {
4616 			/* there was a gap before this data was processed */
4617 			was_a_gap = 1;
4618 		}
4619 		sctp_sack_check(stcb, 1, was_a_gap, &abort_flag);
4620 		if (abort_flag) {
4621 			/* Again, we aborted so NO UNLOCK needed */
4622 			return (0);
4623 		}
4624 	}
4625 	/* trigger send of any chunks in queue... */
4626 trigger_send:
4627 #ifdef SCTP_AUDITING_ENABLED
4628 	sctp_audit_log(0xE0, 2);
4629 	sctp_auditing(1, inp, stcb, net);
4630 #endif
4631 #ifdef SCTP_DEBUG
4632 	if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
4633 		printf("Check for chunk output prw:%d tqe:%d tf=%d\n",
4634 		    stcb->asoc.peers_rwnd,
4635 		    TAILQ_EMPTY(&stcb->asoc.control_send_queue),
4636 		    stcb->asoc.total_flight);
4637 	}
4638 #endif
4639 	un_sent = (stcb->asoc.total_output_queue_size - stcb->asoc.total_flight);
4640 
4641 	if (!TAILQ_EMPTY(&stcb->asoc.control_send_queue) ||
4642 	    ((un_sent) &&
4643 	    (stcb->asoc.peers_rwnd > 0 ||
4644 	    (stcb->asoc.peers_rwnd <= 0 && stcb->asoc.total_flight == 0)))) {
4645 #ifdef SCTP_DEBUG
4646 		if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
4647 			printf("Calling chunk OUTPUT\n");
4648 		}
4649 #endif
4650 		sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_CONTROL_PROC);
4651 #ifdef SCTP_DEBUG
4652 		if (sctp_debug_on & SCTP_DEBUG_INPUT3) {
4653 			printf("chunk OUTPUT returns\n");
4654 		}
4655 #endif
4656 	}
4657 #ifdef SCTP_AUDITING_ENABLED
4658 	sctp_audit_log(0xE0, 3);
4659 	sctp_auditing(2, inp, stcb, net);
4660 #endif
4661 	SCTP_TCB_UNLOCK(stcb);
4662 	return (0);
4663 }
4664 
4665 extern int sctp_no_csum_on_loopback;
4666 
4667 
4668 int sctp_buf_index = 0;
4669 uint8_t sctp_list_of_chunks[30000];
4670 
4671 
4672 void
4673 sctp_input(i_pak, off)
4674 	struct mbuf *i_pak;
4675 	int off;
4676 
4677 {
4678 #ifdef SCTP_MBUF_LOGGING
4679 	struct mbuf *mat;
4680 
4681 #endif
4682 	struct mbuf *m;
4683 	int iphlen;
4684 	uint8_t ecn_bits;
4685 	struct ip *ip;
4686 	struct sctphdr *sh;
4687 	struct sctp_inpcb *inp = NULL;
4688 
4689 	uint32_t check, calc_check;
4690 	struct sctp_nets *net;
4691 	struct sctp_tcb *stcb = NULL;
4692 	struct sctp_chunkhdr *ch;
4693 	int refcount_up = 0;
4694 	int length, mlen, offset;
4695 
4696 
4697 	iphlen = off;
4698 	m = SCTP_HEADER_TO_CHAIN(i_pak);
4699 	net = NULL;
4700 	SCTP_STAT_INCR(sctps_recvpackets);
4701 	SCTP_STAT_INCR_COUNTER64(sctps_inpackets);
4702 
4703 	/*
4704 	 * Strip IP options, we don't allow any in or out.
4705 	 */
4706 #ifdef SCTP_MBUF_LOGGING
4707 	/* Log in any input mbufs */
4708 	mat = m;
4709 	while (mat) {
4710 		if (SCTP_BUF_IS_EXTENDED(mat)) {
4711 			sctp_log_mb(mat, SCTP_MBUF_INPUT);
4712 		}
4713 		mat = SCTP_BUF_NEXT(mat);
4714 	}
4715 #endif
4716 	if ((size_t)iphlen > sizeof(struct ip)) {
4717 		ip_stripoptions(m, (struct mbuf *)0);
4718 		iphlen = sizeof(struct ip);
4719 	}
4720 	/*
4721 	 * Get IP, SCTP, and first chunk header together in first mbuf.
4722 	 */
4723 	ip = mtod(m, struct ip *);
4724 	offset = iphlen + sizeof(*sh) + sizeof(*ch);
4725 	if (SCTP_BUF_LEN(m) < offset) {
4726 		if ((m = m_pullup(m, offset)) == 0) {
4727 			SCTP_STAT_INCR(sctps_hdrops);
4728 			return;
4729 		}
4730 		ip = mtod(m, struct ip *);
4731 	}
4732 	sh = (struct sctphdr *)((caddr_t)ip + iphlen);
4733 	ch = (struct sctp_chunkhdr *)((caddr_t)sh + sizeof(*sh));
4734 
4735 	/* SCTP does not allow broadcasts or multicasts */
4736 	if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
4737 		goto bad;
4738 	}
4739 	if (((ch->chunk_type == SCTP_INITIATION) ||
4740 	    (ch->chunk_type == SCTP_INITIATION_ACK) ||
4741 	    (ch->chunk_type == SCTP_COOKIE_ECHO)) &&
4742 	    (SCTP_IS_IT_BROADCAST(ip->ip_dst, i_pak))) {
4743 		/*
4744 		 * We only look at broadcast if its a front state, All
4745 		 * others we will not have a tcb for anyway.
4746 		 */
4747 		goto bad;
4748 	}
4749 	/* destination port of 0 is illegal, based on RFC2960. */
4750 	if (sh->dest_port == 0) {
4751 		SCTP_STAT_INCR(sctps_hdrops);
4752 		goto bad;
4753 	}
4754 	/* validate SCTP checksum */
4755 	if ((sctp_no_csum_on_loopback == 0) || !SCTP_IS_IT_LOOPBACK(i_pak)) {
4756 		/*
4757 		 * we do NOT validate things from the loopback if the sysctl
4758 		 * is set to 1.
4759 		 */
4760 		check = sh->checksum;	/* save incoming checksum */
4761 		if ((check == 0) && (sctp_no_csum_on_loopback)) {
4762 			/*
4763 			 * special hook for where we got a local address
4764 			 * somehow routed across a non IFT_LOOP type
4765 			 * interface
4766 			 */
4767 			if (ip->ip_src.s_addr == ip->ip_dst.s_addr)
4768 				goto sctp_skip_csum_4;
4769 		}
4770 		sh->checksum = 0;	/* prepare for calc */
4771 		calc_check = sctp_calculate_sum(m, &mlen, iphlen);
4772 		if (calc_check != check) {
4773 #ifdef SCTP_DEBUG
4774 			if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
4775 				printf("Bad CSUM on SCTP packet calc_check:%x check:%x  m:%p mlen:%d iphlen:%d\n",
4776 				    calc_check, check, m, mlen, iphlen);
4777 			}
4778 #endif
4779 
4780 			stcb = sctp_findassociation_addr(m, iphlen,
4781 			    offset - sizeof(*ch),
4782 			    sh, ch, &inp, &net);
4783 			if ((inp) && (stcb)) {
4784 				sctp_send_packet_dropped(stcb, net, m, iphlen, 1);
4785 				sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_INPUT_ERROR);
4786 			} else if ((inp != NULL) && (stcb == NULL)) {
4787 				refcount_up = 1;
4788 			}
4789 			SCTP_STAT_INCR(sctps_badsum);
4790 			SCTP_STAT_INCR_COUNTER32(sctps_checksumerrors);
4791 			goto bad;
4792 		}
4793 		sh->checksum = calc_check;
4794 	} else {
4795 sctp_skip_csum_4:
4796 		mlen = SCTP_HEADER_LEN(i_pak);
4797 	}
4798 	/* validate mbuf chain length with IP payload length */
4799 	if (mlen < (ip->ip_len - iphlen)) {
4800 		SCTP_STAT_INCR(sctps_hdrops);
4801 		goto bad;
4802 	} {
4803 		/* TEMP log the first chunk */
4804 		int x;
4805 
4806 		x = atomic_fetchadd_int(&sctp_buf_index, 1);
4807 		if (x >= 30000) {
4808 			sctp_buf_index = 1;
4809 			x = 0;;
4810 		}
4811 		sctp_list_of_chunks[x] = ch->chunk_type;
4812 	}
4813 	/*
4814 	 * Locate pcb and tcb for datagram sctp_findassociation_addr() wants
4815 	 * IP/SCTP/first chunk header...
4816 	 */
4817 	stcb = sctp_findassociation_addr(m, iphlen, offset - sizeof(*ch),
4818 	    sh, ch, &inp, &net);
4819 	/* inp's ref-count increased && stcb locked */
4820 	if (inp == NULL) {
4821 		struct sctp_init_chunk *init_chk, chunk_buf;
4822 
4823 		SCTP_STAT_INCR(sctps_noport);
4824 #ifdef ICMP_BANDLIM
4825 		/*
4826 		 * we use the bandwidth limiting to protect against sending
4827 		 * too many ABORTS all at once. In this case these count the
4828 		 * same as an ICMP message.
4829 		 */
4830 		if (badport_bandlim(0) < 0)
4831 			goto bad;
4832 #endif				/* ICMP_BANDLIM */
4833 #ifdef SCTP_DEBUG
4834 		if (sctp_debug_on & SCTP_DEBUG_INPUT1) {
4835 			printf("Sending a ABORT from packet entry!\n");
4836 		}
4837 #endif
4838 		if (ch->chunk_type == SCTP_INITIATION) {
4839 			/*
4840 			 * we do a trick here to get the INIT tag, dig in
4841 			 * and get the tag from the INIT and put it in the
4842 			 * common header.
4843 			 */
4844 			init_chk = (struct sctp_init_chunk *)sctp_m_getptr(m,
4845 			    iphlen + sizeof(*sh), sizeof(*init_chk),
4846 			    (uint8_t *) & chunk_buf);
4847 			if (init_chk != NULL)
4848 				sh->v_tag = init_chk->init.initiate_tag;
4849 		}
4850 		if (ch->chunk_type == SCTP_SHUTDOWN_ACK) {
4851 			sctp_send_shutdown_complete2(m, iphlen, sh);
4852 			goto bad;
4853 		}
4854 		if (ch->chunk_type == SCTP_SHUTDOWN_COMPLETE) {
4855 			goto bad;
4856 		}
4857 		if (ch->chunk_type != SCTP_ABORT_ASSOCIATION)
4858 			sctp_send_abort(m, iphlen, sh, 0, NULL);
4859 		goto bad;
4860 	} else if (stcb == NULL) {
4861 		refcount_up = 1;
4862 	}
4863 #ifdef IPSEC
4864 	/*
4865 	 * I very much doubt any of the IPSEC stuff will work but I have no
4866 	 * idea, so I will leave it in place.
4867 	 */
4868 
4869 	if (inp && ipsec4_in_reject(m, &inp->ip_inp.inp)) {
4870 		ipsecstat.in_polvio++;
4871 		SCTP_STAT_INCR(sctps_hdrops);
4872 		goto bad;
4873 	}
4874 #endif				/* IPSEC */
4875 
4876 
4877 
4878 	/*
4879 	 * common chunk processing
4880 	 */
4881 	length = ip->ip_len + iphlen;
4882 	offset -= sizeof(struct sctp_chunkhdr);
4883 
4884 	ecn_bits = ip->ip_tos;
4885 
4886 	sctp_common_input_processing(&m, iphlen, offset, length, sh, ch,
4887 	    inp, stcb, net, ecn_bits);
4888 	/* inp's ref-count reduced && stcb unlocked */
4889 	if (m) {
4890 		sctp_m_freem(m);
4891 	}
4892 	if ((inp) && (refcount_up)) {
4893 		/* reduce ref-count */
4894 		SCTP_INP_WLOCK(inp);
4895 		SCTP_INP_DECR_REF(inp);
4896 		SCTP_INP_WUNLOCK(inp);
4897 	}
4898 	return;
4899 bad:
4900 	if (stcb)
4901 		SCTP_TCB_UNLOCK(stcb);
4902 
4903 	if ((inp) && (refcount_up)) {
4904 		/* reduce ref-count */
4905 		SCTP_INP_WLOCK(inp);
4906 		SCTP_INP_DECR_REF(inp);
4907 		SCTP_INP_WUNLOCK(inp);
4908 	}
4909 	if (m) {
4910 		sctp_m_freem(m);
4911 	}
4912 	return;
4913 }
4914