xref: /linux/net/sctp/stream.c (revision 140eb5227767c6754742020a16d2691222b9c19b)
1 /* SCTP kernel implementation
2  * (C) Copyright IBM Corp. 2001, 2004
3  * Copyright (c) 1999-2000 Cisco, Inc.
4  * Copyright (c) 1999-2001 Motorola, Inc.
5  * Copyright (c) 2001 Intel Corp.
6  *
7  * This file is part of the SCTP kernel implementation
8  *
9  * These functions manipulate sctp tsn mapping array.
10  *
11  * This SCTP implementation is free software;
12  * you can redistribute it and/or modify it under the terms of
13  * the GNU General Public License as published by
14  * the Free Software Foundation; either version 2, or (at your option)
15  * any later version.
16  *
17  * This SCTP implementation is distributed in the hope that it
18  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
19  *                 ************************
20  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
21  * See the GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with GNU CC; see the file COPYING.  If not, see
25  * <http://www.gnu.org/licenses/>.
26  *
27  * Please send any bug reports or fixes you make to the
28  * email address(es):
29  *    lksctp developers <linux-sctp@vger.kernel.org>
30  *
31  * Written or modified by:
32  *    Xin Long <lucien.xin@gmail.com>
33  */
34 
35 #include <linux/list.h>
36 #include <net/sctp/sctp.h>
37 #include <net/sctp/sm.h>
38 #include <net/sctp/stream_sched.h>
39 
40 /* Migrates chunks from stream queues to new stream queues if needed,
41  * but not across associations. Also, removes those chunks to streams
42  * higher than the new max.
43  */
44 static void sctp_stream_outq_migrate(struct sctp_stream *stream,
45 				     struct sctp_stream *new, __u16 outcnt)
46 {
47 	struct sctp_association *asoc;
48 	struct sctp_chunk *ch, *temp;
49 	struct sctp_outq *outq;
50 	int i;
51 
52 	asoc = container_of(stream, struct sctp_association, stream);
53 	outq = &asoc->outqueue;
54 
55 	list_for_each_entry_safe(ch, temp, &outq->out_chunk_list, list) {
56 		__u16 sid = sctp_chunk_stream_no(ch);
57 
58 		if (sid < outcnt)
59 			continue;
60 
61 		sctp_sched_dequeue_common(outq, ch);
62 		/* No need to call dequeue_done here because
63 		 * the chunks are not scheduled by now.
64 		 */
65 
66 		/* Mark as failed send. */
67 		sctp_chunk_fail(ch, (__force __u32)SCTP_ERROR_INV_STRM);
68 		if (asoc->peer.prsctp_capable &&
69 		    SCTP_PR_PRIO_ENABLED(ch->sinfo.sinfo_flags))
70 			asoc->sent_cnt_removable--;
71 
72 		sctp_chunk_free(ch);
73 	}
74 
75 	if (new) {
76 		/* Here we actually move the old ext stuff into the new
77 		 * buffer, because we want to keep it. Then
78 		 * sctp_stream_update will swap ->out pointers.
79 		 */
80 		for (i = 0; i < outcnt; i++) {
81 			kfree(new->out[i].ext);
82 			new->out[i].ext = stream->out[i].ext;
83 			stream->out[i].ext = NULL;
84 		}
85 	}
86 
87 	for (i = outcnt; i < stream->outcnt; i++)
88 		kfree(stream->out[i].ext);
89 }
90 
91 static int sctp_stream_alloc_out(struct sctp_stream *stream, __u16 outcnt,
92 				 gfp_t gfp)
93 {
94 	struct sctp_stream_out *out;
95 
96 	out = kmalloc_array(outcnt, sizeof(*out), gfp);
97 	if (!out)
98 		return -ENOMEM;
99 
100 	if (stream->out) {
101 		memcpy(out, stream->out, min(outcnt, stream->outcnt) *
102 					 sizeof(*out));
103 		kfree(stream->out);
104 	}
105 
106 	if (outcnt > stream->outcnt)
107 		memset(out + stream->outcnt, 0,
108 		       (outcnt - stream->outcnt) * sizeof(*out));
109 
110 	stream->out = out;
111 
112 	return 0;
113 }
114 
115 static int sctp_stream_alloc_in(struct sctp_stream *stream, __u16 incnt,
116 				gfp_t gfp)
117 {
118 	struct sctp_stream_in *in;
119 
120 	in = kmalloc_array(incnt, sizeof(*stream->in), gfp);
121 
122 	if (!in)
123 		return -ENOMEM;
124 
125 	if (stream->in) {
126 		memcpy(in, stream->in, min(incnt, stream->incnt) *
127 				       sizeof(*in));
128 		kfree(stream->in);
129 	}
130 
131 	if (incnt > stream->incnt)
132 		memset(in + stream->incnt, 0,
133 		       (incnt - stream->incnt) * sizeof(*in));
134 
135 	stream->in = in;
136 
137 	return 0;
138 }
139 
140 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt,
141 		     gfp_t gfp)
142 {
143 	struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
144 	int i, ret = 0;
145 
146 	gfp |= __GFP_NOWARN;
147 
148 	/* Initial stream->out size may be very big, so free it and alloc
149 	 * a new one with new outcnt to save memory if needed.
150 	 */
151 	if (outcnt == stream->outcnt)
152 		goto in;
153 
154 	/* Filter out chunks queued on streams that won't exist anymore */
155 	sched->unsched_all(stream);
156 	sctp_stream_outq_migrate(stream, NULL, outcnt);
157 	sched->sched_all(stream);
158 
159 	ret = sctp_stream_alloc_out(stream, outcnt, gfp);
160 	if (ret)
161 		goto out;
162 
163 	stream->outcnt = outcnt;
164 	for (i = 0; i < stream->outcnt; i++)
165 		stream->out[i].state = SCTP_STREAM_OPEN;
166 
167 	sched->init(stream);
168 
169 in:
170 	if (!incnt)
171 		goto out;
172 
173 	ret = sctp_stream_alloc_in(stream, incnt, gfp);
174 	if (ret) {
175 		sched->free(stream);
176 		kfree(stream->out);
177 		stream->out = NULL;
178 		stream->outcnt = 0;
179 		goto out;
180 	}
181 
182 	stream->incnt = incnt;
183 
184 out:
185 	return ret;
186 }
187 
188 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid)
189 {
190 	struct sctp_stream_out_ext *soute;
191 
192 	soute = kzalloc(sizeof(*soute), GFP_KERNEL);
193 	if (!soute)
194 		return -ENOMEM;
195 	stream->out[sid].ext = soute;
196 
197 	return sctp_sched_init_sid(stream, sid, GFP_KERNEL);
198 }
199 
200 void sctp_stream_free(struct sctp_stream *stream)
201 {
202 	struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
203 	int i;
204 
205 	sched->free(stream);
206 	for (i = 0; i < stream->outcnt; i++)
207 		kfree(stream->out[i].ext);
208 	kfree(stream->out);
209 	kfree(stream->in);
210 }
211 
212 void sctp_stream_clear(struct sctp_stream *stream)
213 {
214 	int i;
215 
216 	for (i = 0; i < stream->outcnt; i++)
217 		stream->out[i].ssn = 0;
218 
219 	for (i = 0; i < stream->incnt; i++)
220 		stream->in[i].ssn = 0;
221 }
222 
223 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new)
224 {
225 	struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
226 
227 	sched->unsched_all(stream);
228 	sctp_stream_outq_migrate(stream, new, new->outcnt);
229 	sctp_stream_free(stream);
230 
231 	stream->out = new->out;
232 	stream->in  = new->in;
233 	stream->outcnt = new->outcnt;
234 	stream->incnt  = new->incnt;
235 
236 	sched->sched_all(stream);
237 
238 	new->out = NULL;
239 	new->in  = NULL;
240 }
241 
242 static int sctp_send_reconf(struct sctp_association *asoc,
243 			    struct sctp_chunk *chunk)
244 {
245 	struct net *net = sock_net(asoc->base.sk);
246 	int retval = 0;
247 
248 	retval = sctp_primitive_RECONF(net, asoc, chunk);
249 	if (retval)
250 		sctp_chunk_free(chunk);
251 
252 	return retval;
253 }
254 
255 static bool sctp_stream_outq_is_empty(struct sctp_stream *stream,
256 				      __u16 str_nums, __be16 *str_list)
257 {
258 	struct sctp_association *asoc;
259 	__u16 i;
260 
261 	asoc = container_of(stream, struct sctp_association, stream);
262 	if (!asoc->outqueue.out_qlen)
263 		return true;
264 
265 	if (!str_nums)
266 		return false;
267 
268 	for (i = 0; i < str_nums; i++) {
269 		__u16 sid = ntohs(str_list[i]);
270 
271 		if (stream->out[sid].ext &&
272 		    !list_empty(&stream->out[sid].ext->outq))
273 			return false;
274 	}
275 
276 	return true;
277 }
278 
279 int sctp_send_reset_streams(struct sctp_association *asoc,
280 			    struct sctp_reset_streams *params)
281 {
282 	struct sctp_stream *stream = &asoc->stream;
283 	__u16 i, str_nums, *str_list;
284 	struct sctp_chunk *chunk;
285 	int retval = -EINVAL;
286 	__be16 *nstr_list;
287 	bool out, in;
288 
289 	if (!asoc->peer.reconf_capable ||
290 	    !(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ)) {
291 		retval = -ENOPROTOOPT;
292 		goto out;
293 	}
294 
295 	if (asoc->strreset_outstanding) {
296 		retval = -EINPROGRESS;
297 		goto out;
298 	}
299 
300 	out = params->srs_flags & SCTP_STREAM_RESET_OUTGOING;
301 	in  = params->srs_flags & SCTP_STREAM_RESET_INCOMING;
302 	if (!out && !in)
303 		goto out;
304 
305 	str_nums = params->srs_number_streams;
306 	str_list = params->srs_stream_list;
307 	if (str_nums) {
308 		int param_len = 0;
309 
310 		if (out) {
311 			for (i = 0; i < str_nums; i++)
312 				if (str_list[i] >= stream->outcnt)
313 					goto out;
314 
315 			param_len = str_nums * sizeof(__u16) +
316 				    sizeof(struct sctp_strreset_outreq);
317 		}
318 
319 		if (in) {
320 			for (i = 0; i < str_nums; i++)
321 				if (str_list[i] >= stream->incnt)
322 					goto out;
323 
324 			param_len += str_nums * sizeof(__u16) +
325 				     sizeof(struct sctp_strreset_inreq);
326 		}
327 
328 		if (param_len > SCTP_MAX_CHUNK_LEN -
329 				sizeof(struct sctp_reconf_chunk))
330 			goto out;
331 	}
332 
333 	nstr_list = kcalloc(str_nums, sizeof(__be16), GFP_KERNEL);
334 	if (!nstr_list) {
335 		retval = -ENOMEM;
336 		goto out;
337 	}
338 
339 	for (i = 0; i < str_nums; i++)
340 		nstr_list[i] = htons(str_list[i]);
341 
342 	if (out && !sctp_stream_outq_is_empty(stream, str_nums, nstr_list)) {
343 		retval = -EAGAIN;
344 		goto out;
345 	}
346 
347 	chunk = sctp_make_strreset_req(asoc, str_nums, nstr_list, out, in);
348 
349 	kfree(nstr_list);
350 
351 	if (!chunk) {
352 		retval = -ENOMEM;
353 		goto out;
354 	}
355 
356 	if (out) {
357 		if (str_nums)
358 			for (i = 0; i < str_nums; i++)
359 				stream->out[str_list[i]].state =
360 						       SCTP_STREAM_CLOSED;
361 		else
362 			for (i = 0; i < stream->outcnt; i++)
363 				stream->out[i].state = SCTP_STREAM_CLOSED;
364 	}
365 
366 	asoc->strreset_chunk = chunk;
367 	sctp_chunk_hold(asoc->strreset_chunk);
368 
369 	retval = sctp_send_reconf(asoc, chunk);
370 	if (retval) {
371 		sctp_chunk_put(asoc->strreset_chunk);
372 		asoc->strreset_chunk = NULL;
373 		if (!out)
374 			goto out;
375 
376 		if (str_nums)
377 			for (i = 0; i < str_nums; i++)
378 				stream->out[str_list[i]].state =
379 						       SCTP_STREAM_OPEN;
380 		else
381 			for (i = 0; i < stream->outcnt; i++)
382 				stream->out[i].state = SCTP_STREAM_OPEN;
383 
384 		goto out;
385 	}
386 
387 	asoc->strreset_outstanding = out + in;
388 
389 out:
390 	return retval;
391 }
392 
393 int sctp_send_reset_assoc(struct sctp_association *asoc)
394 {
395 	struct sctp_stream *stream = &asoc->stream;
396 	struct sctp_chunk *chunk = NULL;
397 	int retval;
398 	__u16 i;
399 
400 	if (!asoc->peer.reconf_capable ||
401 	    !(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
402 		return -ENOPROTOOPT;
403 
404 	if (asoc->strreset_outstanding)
405 		return -EINPROGRESS;
406 
407 	if (!sctp_outq_is_empty(&asoc->outqueue))
408 		return -EAGAIN;
409 
410 	chunk = sctp_make_strreset_tsnreq(asoc);
411 	if (!chunk)
412 		return -ENOMEM;
413 
414 	/* Block further xmit of data until this request is completed */
415 	for (i = 0; i < stream->outcnt; i++)
416 		stream->out[i].state = SCTP_STREAM_CLOSED;
417 
418 	asoc->strreset_chunk = chunk;
419 	sctp_chunk_hold(asoc->strreset_chunk);
420 
421 	retval = sctp_send_reconf(asoc, chunk);
422 	if (retval) {
423 		sctp_chunk_put(asoc->strreset_chunk);
424 		asoc->strreset_chunk = NULL;
425 
426 		for (i = 0; i < stream->outcnt; i++)
427 			stream->out[i].state = SCTP_STREAM_OPEN;
428 
429 		return retval;
430 	}
431 
432 	asoc->strreset_outstanding = 1;
433 
434 	return 0;
435 }
436 
437 int sctp_send_add_streams(struct sctp_association *asoc,
438 			  struct sctp_add_streams *params)
439 {
440 	struct sctp_stream *stream = &asoc->stream;
441 	struct sctp_chunk *chunk = NULL;
442 	int retval;
443 	__u32 outcnt, incnt;
444 	__u16 out, in;
445 
446 	if (!asoc->peer.reconf_capable ||
447 	    !(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ)) {
448 		retval = -ENOPROTOOPT;
449 		goto out;
450 	}
451 
452 	if (asoc->strreset_outstanding) {
453 		retval = -EINPROGRESS;
454 		goto out;
455 	}
456 
457 	out = params->sas_outstrms;
458 	in  = params->sas_instrms;
459 	outcnt = stream->outcnt + out;
460 	incnt = stream->incnt + in;
461 	if (outcnt > SCTP_MAX_STREAM || incnt > SCTP_MAX_STREAM ||
462 	    (!out && !in)) {
463 		retval = -EINVAL;
464 		goto out;
465 	}
466 
467 	if (out) {
468 		retval = sctp_stream_alloc_out(stream, outcnt, GFP_KERNEL);
469 		if (retval)
470 			goto out;
471 	}
472 
473 	chunk = sctp_make_strreset_addstrm(asoc, out, in);
474 	if (!chunk) {
475 		retval = -ENOMEM;
476 		goto out;
477 	}
478 
479 	asoc->strreset_chunk = chunk;
480 	sctp_chunk_hold(asoc->strreset_chunk);
481 
482 	retval = sctp_send_reconf(asoc, chunk);
483 	if (retval) {
484 		sctp_chunk_put(asoc->strreset_chunk);
485 		asoc->strreset_chunk = NULL;
486 		goto out;
487 	}
488 
489 	stream->incnt = incnt;
490 	stream->outcnt = outcnt;
491 
492 	asoc->strreset_outstanding = !!out + !!in;
493 
494 out:
495 	return retval;
496 }
497 
498 static struct sctp_paramhdr *sctp_chunk_lookup_strreset_param(
499 			struct sctp_association *asoc, __be32 resp_seq,
500 			__be16 type)
501 {
502 	struct sctp_chunk *chunk = asoc->strreset_chunk;
503 	struct sctp_reconf_chunk *hdr;
504 	union sctp_params param;
505 
506 	if (!chunk)
507 		return NULL;
508 
509 	hdr = (struct sctp_reconf_chunk *)chunk->chunk_hdr;
510 	sctp_walk_params(param, hdr, params) {
511 		/* sctp_strreset_tsnreq is actually the basic structure
512 		 * of all stream reconf params, so it's safe to use it
513 		 * to access request_seq.
514 		 */
515 		struct sctp_strreset_tsnreq *req = param.v;
516 
517 		if ((!resp_seq || req->request_seq == resp_seq) &&
518 		    (!type || type == req->param_hdr.type))
519 			return param.v;
520 	}
521 
522 	return NULL;
523 }
524 
525 static void sctp_update_strreset_result(struct sctp_association *asoc,
526 					__u32 result)
527 {
528 	asoc->strreset_result[1] = asoc->strreset_result[0];
529 	asoc->strreset_result[0] = result;
530 }
531 
532 struct sctp_chunk *sctp_process_strreset_outreq(
533 				struct sctp_association *asoc,
534 				union sctp_params param,
535 				struct sctp_ulpevent **evp)
536 {
537 	struct sctp_strreset_outreq *outreq = param.v;
538 	struct sctp_stream *stream = &asoc->stream;
539 	__u32 result = SCTP_STRRESET_DENIED;
540 	__u16 i, nums, flags = 0;
541 	__be16 *str_p = NULL;
542 	__u32 request_seq;
543 
544 	request_seq = ntohl(outreq->request_seq);
545 
546 	if (ntohl(outreq->send_reset_at_tsn) >
547 	    sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map)) {
548 		result = SCTP_STRRESET_IN_PROGRESS;
549 		goto err;
550 	}
551 
552 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
553 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
554 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
555 		goto err;
556 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
557 		i = asoc->strreset_inseq - request_seq - 1;
558 		result = asoc->strreset_result[i];
559 		goto err;
560 	}
561 	asoc->strreset_inseq++;
562 
563 	/* Check strreset_enable after inseq inc, as sender cannot tell
564 	 * the peer doesn't enable strreset after receiving response with
565 	 * result denied, as well as to keep consistent with bsd.
566 	 */
567 	if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
568 		goto out;
569 
570 	if (asoc->strreset_chunk) {
571 		if (!sctp_chunk_lookup_strreset_param(
572 				asoc, outreq->response_seq,
573 				SCTP_PARAM_RESET_IN_REQUEST)) {
574 			/* same process with outstanding isn't 0 */
575 			result = SCTP_STRRESET_ERR_IN_PROGRESS;
576 			goto out;
577 		}
578 
579 		asoc->strreset_outstanding--;
580 		asoc->strreset_outseq++;
581 
582 		if (!asoc->strreset_outstanding) {
583 			struct sctp_transport *t;
584 
585 			t = asoc->strreset_chunk->transport;
586 			if (del_timer(&t->reconf_timer))
587 				sctp_transport_put(t);
588 
589 			sctp_chunk_put(asoc->strreset_chunk);
590 			asoc->strreset_chunk = NULL;
591 		}
592 
593 		flags = SCTP_STREAM_RESET_INCOMING_SSN;
594 	}
595 
596 	nums = (ntohs(param.p->length) - sizeof(*outreq)) / sizeof(__u16);
597 	if (nums) {
598 		str_p = outreq->list_of_streams;
599 		for (i = 0; i < nums; i++) {
600 			if (ntohs(str_p[i]) >= stream->incnt) {
601 				result = SCTP_STRRESET_ERR_WRONG_SSN;
602 				goto out;
603 			}
604 		}
605 
606 		for (i = 0; i < nums; i++)
607 			stream->in[ntohs(str_p[i])].ssn = 0;
608 	} else {
609 		for (i = 0; i < stream->incnt; i++)
610 			stream->in[i].ssn = 0;
611 	}
612 
613 	result = SCTP_STRRESET_PERFORMED;
614 
615 	*evp = sctp_ulpevent_make_stream_reset_event(asoc,
616 		flags | SCTP_STREAM_RESET_OUTGOING_SSN, nums, str_p,
617 		GFP_ATOMIC);
618 
619 out:
620 	sctp_update_strreset_result(asoc, result);
621 err:
622 	return sctp_make_strreset_resp(asoc, result, request_seq);
623 }
624 
625 struct sctp_chunk *sctp_process_strreset_inreq(
626 				struct sctp_association *asoc,
627 				union sctp_params param,
628 				struct sctp_ulpevent **evp)
629 {
630 	struct sctp_strreset_inreq *inreq = param.v;
631 	struct sctp_stream *stream = &asoc->stream;
632 	__u32 result = SCTP_STRRESET_DENIED;
633 	struct sctp_chunk *chunk = NULL;
634 	__u32 request_seq;
635 	__u16 i, nums;
636 	__be16 *str_p;
637 
638 	request_seq = ntohl(inreq->request_seq);
639 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
640 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
641 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
642 		goto err;
643 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
644 		i = asoc->strreset_inseq - request_seq - 1;
645 		result = asoc->strreset_result[i];
646 		if (result == SCTP_STRRESET_PERFORMED)
647 			return NULL;
648 		goto err;
649 	}
650 	asoc->strreset_inseq++;
651 
652 	if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
653 		goto out;
654 
655 	if (asoc->strreset_outstanding) {
656 		result = SCTP_STRRESET_ERR_IN_PROGRESS;
657 		goto out;
658 	}
659 
660 	nums = (ntohs(param.p->length) - sizeof(*inreq)) / sizeof(__u16);
661 	str_p = inreq->list_of_streams;
662 	for (i = 0; i < nums; i++) {
663 		if (ntohs(str_p[i]) >= stream->outcnt) {
664 			result = SCTP_STRRESET_ERR_WRONG_SSN;
665 			goto out;
666 		}
667 	}
668 
669 	if (!sctp_stream_outq_is_empty(stream, nums, str_p)) {
670 		result = SCTP_STRRESET_IN_PROGRESS;
671 		asoc->strreset_inseq--;
672 		goto err;
673 	}
674 
675 	chunk = sctp_make_strreset_req(asoc, nums, str_p, 1, 0);
676 	if (!chunk)
677 		goto out;
678 
679 	if (nums)
680 		for (i = 0; i < nums; i++)
681 			stream->out[ntohs(str_p[i])].state =
682 					       SCTP_STREAM_CLOSED;
683 	else
684 		for (i = 0; i < stream->outcnt; i++)
685 			stream->out[i].state = SCTP_STREAM_CLOSED;
686 
687 	asoc->strreset_chunk = chunk;
688 	asoc->strreset_outstanding = 1;
689 	sctp_chunk_hold(asoc->strreset_chunk);
690 
691 	result = SCTP_STRRESET_PERFORMED;
692 
693 	*evp = sctp_ulpevent_make_stream_reset_event(asoc,
694 		SCTP_STREAM_RESET_INCOMING_SSN, nums, str_p, GFP_ATOMIC);
695 
696 out:
697 	sctp_update_strreset_result(asoc, result);
698 err:
699 	if (!chunk)
700 		chunk =  sctp_make_strreset_resp(asoc, result, request_seq);
701 
702 	return chunk;
703 }
704 
705 struct sctp_chunk *sctp_process_strreset_tsnreq(
706 				struct sctp_association *asoc,
707 				union sctp_params param,
708 				struct sctp_ulpevent **evp)
709 {
710 	__u32 init_tsn = 0, next_tsn = 0, max_tsn_seen;
711 	struct sctp_strreset_tsnreq *tsnreq = param.v;
712 	struct sctp_stream *stream = &asoc->stream;
713 	__u32 result = SCTP_STRRESET_DENIED;
714 	__u32 request_seq;
715 	__u16 i;
716 
717 	request_seq = ntohl(tsnreq->request_seq);
718 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
719 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
720 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
721 		goto err;
722 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
723 		i = asoc->strreset_inseq - request_seq - 1;
724 		result = asoc->strreset_result[i];
725 		if (result == SCTP_STRRESET_PERFORMED) {
726 			next_tsn = asoc->ctsn_ack_point + 1;
727 			init_tsn =
728 				sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + 1;
729 		}
730 		goto err;
731 	}
732 
733 	if (!sctp_outq_is_empty(&asoc->outqueue)) {
734 		result = SCTP_STRRESET_IN_PROGRESS;
735 		goto err;
736 	}
737 
738 	asoc->strreset_inseq++;
739 
740 	if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
741 		goto out;
742 
743 	if (asoc->strreset_outstanding) {
744 		result = SCTP_STRRESET_ERR_IN_PROGRESS;
745 		goto out;
746 	}
747 
748 	/* G4: The same processing as though a FWD-TSN chunk (as defined in
749 	 *     [RFC3758]) with all streams affected and a new cumulative TSN
750 	 *     ACK of the Receiver's Next TSN minus 1 were received MUST be
751 	 *     performed.
752 	 */
753 	max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
754 	sctp_ulpq_reasm_flushtsn(&asoc->ulpq, max_tsn_seen);
755 	sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
756 
757 	/* G1: Compute an appropriate value for the Receiver's Next TSN -- the
758 	 *     TSN that the peer should use to send the next DATA chunk.  The
759 	 *     value SHOULD be the smallest TSN not acknowledged by the
760 	 *     receiver of the request plus 2^31.
761 	 */
762 	init_tsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + (1 << 31);
763 	sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
764 			 init_tsn, GFP_ATOMIC);
765 
766 	/* G3: The same processing as though a SACK chunk with no gap report
767 	 *     and a cumulative TSN ACK of the Sender's Next TSN minus 1 were
768 	 *     received MUST be performed.
769 	 */
770 	sctp_outq_free(&asoc->outqueue);
771 
772 	/* G2: Compute an appropriate value for the local endpoint's next TSN,
773 	 *     i.e., the next TSN assigned by the receiver of the SSN/TSN reset
774 	 *     chunk.  The value SHOULD be the highest TSN sent by the receiver
775 	 *     of the request plus 1.
776 	 */
777 	next_tsn = asoc->next_tsn;
778 	asoc->ctsn_ack_point = next_tsn - 1;
779 	asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
780 
781 	/* G5:  The next expected and outgoing SSNs MUST be reset to 0 for all
782 	 *      incoming and outgoing streams.
783 	 */
784 	for (i = 0; i < stream->outcnt; i++)
785 		stream->out[i].ssn = 0;
786 	for (i = 0; i < stream->incnt; i++)
787 		stream->in[i].ssn = 0;
788 
789 	result = SCTP_STRRESET_PERFORMED;
790 
791 	*evp = sctp_ulpevent_make_assoc_reset_event(asoc, 0, init_tsn,
792 						    next_tsn, GFP_ATOMIC);
793 
794 out:
795 	sctp_update_strreset_result(asoc, result);
796 err:
797 	return sctp_make_strreset_tsnresp(asoc, result, request_seq,
798 					  next_tsn, init_tsn);
799 }
800 
801 struct sctp_chunk *sctp_process_strreset_addstrm_out(
802 				struct sctp_association *asoc,
803 				union sctp_params param,
804 				struct sctp_ulpevent **evp)
805 {
806 	struct sctp_strreset_addstrm *addstrm = param.v;
807 	struct sctp_stream *stream = &asoc->stream;
808 	__u32 result = SCTP_STRRESET_DENIED;
809 	__u32 request_seq, incnt;
810 	__u16 in, i;
811 
812 	request_seq = ntohl(addstrm->request_seq);
813 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
814 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
815 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
816 		goto err;
817 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
818 		i = asoc->strreset_inseq - request_seq - 1;
819 		result = asoc->strreset_result[i];
820 		goto err;
821 	}
822 	asoc->strreset_inseq++;
823 
824 	if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
825 		goto out;
826 
827 	if (asoc->strreset_chunk) {
828 		if (!sctp_chunk_lookup_strreset_param(
829 			asoc, 0, SCTP_PARAM_RESET_ADD_IN_STREAMS)) {
830 			/* same process with outstanding isn't 0 */
831 			result = SCTP_STRRESET_ERR_IN_PROGRESS;
832 			goto out;
833 		}
834 
835 		asoc->strreset_outstanding--;
836 		asoc->strreset_outseq++;
837 
838 		if (!asoc->strreset_outstanding) {
839 			struct sctp_transport *t;
840 
841 			t = asoc->strreset_chunk->transport;
842 			if (del_timer(&t->reconf_timer))
843 				sctp_transport_put(t);
844 
845 			sctp_chunk_put(asoc->strreset_chunk);
846 			asoc->strreset_chunk = NULL;
847 		}
848 	}
849 
850 	in = ntohs(addstrm->number_of_streams);
851 	incnt = stream->incnt + in;
852 	if (!in || incnt > SCTP_MAX_STREAM)
853 		goto out;
854 
855 	if (sctp_stream_alloc_in(stream, incnt, GFP_ATOMIC))
856 		goto out;
857 
858 	stream->incnt = incnt;
859 
860 	result = SCTP_STRRESET_PERFORMED;
861 
862 	*evp = sctp_ulpevent_make_stream_change_event(asoc,
863 		0, ntohs(addstrm->number_of_streams), 0, GFP_ATOMIC);
864 
865 out:
866 	sctp_update_strreset_result(asoc, result);
867 err:
868 	return sctp_make_strreset_resp(asoc, result, request_seq);
869 }
870 
871 struct sctp_chunk *sctp_process_strreset_addstrm_in(
872 				struct sctp_association *asoc,
873 				union sctp_params param,
874 				struct sctp_ulpevent **evp)
875 {
876 	struct sctp_strreset_addstrm *addstrm = param.v;
877 	struct sctp_stream *stream = &asoc->stream;
878 	__u32 result = SCTP_STRRESET_DENIED;
879 	struct sctp_chunk *chunk = NULL;
880 	__u32 request_seq, outcnt;
881 	__u16 out, i;
882 	int ret;
883 
884 	request_seq = ntohl(addstrm->request_seq);
885 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
886 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
887 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
888 		goto err;
889 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
890 		i = asoc->strreset_inseq - request_seq - 1;
891 		result = asoc->strreset_result[i];
892 		if (result == SCTP_STRRESET_PERFORMED)
893 			return NULL;
894 		goto err;
895 	}
896 	asoc->strreset_inseq++;
897 
898 	if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
899 		goto out;
900 
901 	if (asoc->strreset_outstanding) {
902 		result = SCTP_STRRESET_ERR_IN_PROGRESS;
903 		goto out;
904 	}
905 
906 	out = ntohs(addstrm->number_of_streams);
907 	outcnt = stream->outcnt + out;
908 	if (!out || outcnt > SCTP_MAX_STREAM)
909 		goto out;
910 
911 	ret = sctp_stream_alloc_out(stream, outcnt, GFP_ATOMIC);
912 	if (ret)
913 		goto out;
914 
915 	chunk = sctp_make_strreset_addstrm(asoc, out, 0);
916 	if (!chunk)
917 		goto out;
918 
919 	asoc->strreset_chunk = chunk;
920 	asoc->strreset_outstanding = 1;
921 	sctp_chunk_hold(asoc->strreset_chunk);
922 
923 	stream->outcnt = outcnt;
924 
925 	result = SCTP_STRRESET_PERFORMED;
926 
927 	*evp = sctp_ulpevent_make_stream_change_event(asoc,
928 		0, 0, ntohs(addstrm->number_of_streams), GFP_ATOMIC);
929 
930 out:
931 	sctp_update_strreset_result(asoc, result);
932 err:
933 	if (!chunk)
934 		chunk = sctp_make_strreset_resp(asoc, result, request_seq);
935 
936 	return chunk;
937 }
938 
939 struct sctp_chunk *sctp_process_strreset_resp(
940 				struct sctp_association *asoc,
941 				union sctp_params param,
942 				struct sctp_ulpevent **evp)
943 {
944 	struct sctp_stream *stream = &asoc->stream;
945 	struct sctp_strreset_resp *resp = param.v;
946 	struct sctp_transport *t;
947 	__u16 i, nums, flags = 0;
948 	struct sctp_paramhdr *req;
949 	__u32 result;
950 
951 	req = sctp_chunk_lookup_strreset_param(asoc, resp->response_seq, 0);
952 	if (!req)
953 		return NULL;
954 
955 	result = ntohl(resp->result);
956 	if (result != SCTP_STRRESET_PERFORMED) {
957 		/* if in progress, do nothing but retransmit */
958 		if (result == SCTP_STRRESET_IN_PROGRESS)
959 			return NULL;
960 		else if (result == SCTP_STRRESET_DENIED)
961 			flags = SCTP_STREAM_RESET_DENIED;
962 		else
963 			flags = SCTP_STREAM_RESET_FAILED;
964 	}
965 
966 	if (req->type == SCTP_PARAM_RESET_OUT_REQUEST) {
967 		struct sctp_strreset_outreq *outreq;
968 		__be16 *str_p;
969 
970 		outreq = (struct sctp_strreset_outreq *)req;
971 		str_p = outreq->list_of_streams;
972 		nums = (ntohs(outreq->param_hdr.length) - sizeof(*outreq)) /
973 		       sizeof(__u16);
974 
975 		if (result == SCTP_STRRESET_PERFORMED) {
976 			if (nums) {
977 				for (i = 0; i < nums; i++)
978 					stream->out[ntohs(str_p[i])].ssn = 0;
979 			} else {
980 				for (i = 0; i < stream->outcnt; i++)
981 					stream->out[i].ssn = 0;
982 			}
983 
984 			flags = SCTP_STREAM_RESET_OUTGOING_SSN;
985 		}
986 
987 		for (i = 0; i < stream->outcnt; i++)
988 			stream->out[i].state = SCTP_STREAM_OPEN;
989 
990 		*evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
991 			nums, str_p, GFP_ATOMIC);
992 	} else if (req->type == SCTP_PARAM_RESET_IN_REQUEST) {
993 		struct sctp_strreset_inreq *inreq;
994 		__be16 *str_p;
995 
996 		/* if the result is performed, it's impossible for inreq */
997 		if (result == SCTP_STRRESET_PERFORMED)
998 			return NULL;
999 
1000 		inreq = (struct sctp_strreset_inreq *)req;
1001 		str_p = inreq->list_of_streams;
1002 		nums = (ntohs(inreq->param_hdr.length) - sizeof(*inreq)) /
1003 		       sizeof(__u16);
1004 
1005 		*evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
1006 			nums, str_p, GFP_ATOMIC);
1007 	} else if (req->type == SCTP_PARAM_RESET_TSN_REQUEST) {
1008 		struct sctp_strreset_resptsn *resptsn;
1009 		__u32 stsn, rtsn;
1010 
1011 		/* check for resptsn, as sctp_verify_reconf didn't do it*/
1012 		if (ntohs(param.p->length) != sizeof(*resptsn))
1013 			return NULL;
1014 
1015 		resptsn = (struct sctp_strreset_resptsn *)resp;
1016 		stsn = ntohl(resptsn->senders_next_tsn);
1017 		rtsn = ntohl(resptsn->receivers_next_tsn);
1018 
1019 		if (result == SCTP_STRRESET_PERFORMED) {
1020 			__u32 mtsn = sctp_tsnmap_get_max_tsn_seen(
1021 						&asoc->peer.tsn_map);
1022 			LIST_HEAD(temp);
1023 
1024 			sctp_ulpq_reasm_flushtsn(&asoc->ulpq, mtsn);
1025 			sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
1026 
1027 			sctp_tsnmap_init(&asoc->peer.tsn_map,
1028 					 SCTP_TSN_MAP_INITIAL,
1029 					 stsn, GFP_ATOMIC);
1030 
1031 			/* Clean up sacked and abandoned queues only. As the
1032 			 * out_chunk_list may not be empty, splice it to temp,
1033 			 * then get it back after sctp_outq_free is done.
1034 			 */
1035 			list_splice_init(&asoc->outqueue.out_chunk_list, &temp);
1036 			sctp_outq_free(&asoc->outqueue);
1037 			list_splice_init(&temp, &asoc->outqueue.out_chunk_list);
1038 
1039 			asoc->next_tsn = rtsn;
1040 			asoc->ctsn_ack_point = asoc->next_tsn - 1;
1041 			asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
1042 
1043 			for (i = 0; i < stream->outcnt; i++)
1044 				stream->out[i].ssn = 0;
1045 			for (i = 0; i < stream->incnt; i++)
1046 				stream->in[i].ssn = 0;
1047 		}
1048 
1049 		for (i = 0; i < stream->outcnt; i++)
1050 			stream->out[i].state = SCTP_STREAM_OPEN;
1051 
1052 		*evp = sctp_ulpevent_make_assoc_reset_event(asoc, flags,
1053 			stsn, rtsn, GFP_ATOMIC);
1054 	} else if (req->type == SCTP_PARAM_RESET_ADD_OUT_STREAMS) {
1055 		struct sctp_strreset_addstrm *addstrm;
1056 		__u16 number;
1057 
1058 		addstrm = (struct sctp_strreset_addstrm *)req;
1059 		nums = ntohs(addstrm->number_of_streams);
1060 		number = stream->outcnt - nums;
1061 
1062 		if (result == SCTP_STRRESET_PERFORMED)
1063 			for (i = number; i < stream->outcnt; i++)
1064 				stream->out[i].state = SCTP_STREAM_OPEN;
1065 		else
1066 			stream->outcnt = number;
1067 
1068 		*evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1069 			0, nums, GFP_ATOMIC);
1070 	} else if (req->type == SCTP_PARAM_RESET_ADD_IN_STREAMS) {
1071 		struct sctp_strreset_addstrm *addstrm;
1072 
1073 		/* if the result is performed, it's impossible for addstrm in
1074 		 * request.
1075 		 */
1076 		if (result == SCTP_STRRESET_PERFORMED)
1077 			return NULL;
1078 
1079 		addstrm = (struct sctp_strreset_addstrm *)req;
1080 		nums = ntohs(addstrm->number_of_streams);
1081 
1082 		*evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1083 			nums, 0, GFP_ATOMIC);
1084 	}
1085 
1086 	asoc->strreset_outstanding--;
1087 	asoc->strreset_outseq++;
1088 
1089 	/* remove everything for this reconf request */
1090 	if (!asoc->strreset_outstanding) {
1091 		t = asoc->strreset_chunk->transport;
1092 		if (del_timer(&t->reconf_timer))
1093 			sctp_transport_put(t);
1094 
1095 		sctp_chunk_put(asoc->strreset_chunk);
1096 		asoc->strreset_chunk = NULL;
1097 	}
1098 
1099 	return NULL;
1100 }
1101