xref: /openbmc/linux/net/sctp/stream.c (revision a9a08845)
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 	sctp_stream_interleave_init(stream);
171 	if (!incnt)
172 		goto out;
173 
174 	ret = sctp_stream_alloc_in(stream, incnt, gfp);
175 	if (ret) {
176 		sched->free(stream);
177 		kfree(stream->out);
178 		stream->out = NULL;
179 		stream->outcnt = 0;
180 		goto out;
181 	}
182 
183 	stream->incnt = incnt;
184 
185 out:
186 	return ret;
187 }
188 
189 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid)
190 {
191 	struct sctp_stream_out_ext *soute;
192 
193 	soute = kzalloc(sizeof(*soute), GFP_KERNEL);
194 	if (!soute)
195 		return -ENOMEM;
196 	stream->out[sid].ext = soute;
197 
198 	return sctp_sched_init_sid(stream, sid, GFP_KERNEL);
199 }
200 
201 void sctp_stream_free(struct sctp_stream *stream)
202 {
203 	struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
204 	int i;
205 
206 	sched->free(stream);
207 	for (i = 0; i < stream->outcnt; i++)
208 		kfree(stream->out[i].ext);
209 	kfree(stream->out);
210 	kfree(stream->in);
211 }
212 
213 void sctp_stream_clear(struct sctp_stream *stream)
214 {
215 	int i;
216 
217 	for (i = 0; i < stream->outcnt; i++) {
218 		stream->out[i].mid = 0;
219 		stream->out[i].mid_uo = 0;
220 	}
221 
222 	for (i = 0; i < stream->incnt; i++)
223 		stream->in[i].mid = 0;
224 }
225 
226 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new)
227 {
228 	struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
229 
230 	sched->unsched_all(stream);
231 	sctp_stream_outq_migrate(stream, new, new->outcnt);
232 	sctp_stream_free(stream);
233 
234 	stream->out = new->out;
235 	stream->in  = new->in;
236 	stream->outcnt = new->outcnt;
237 	stream->incnt  = new->incnt;
238 
239 	sched->sched_all(stream);
240 
241 	new->out = NULL;
242 	new->in  = NULL;
243 }
244 
245 static int sctp_send_reconf(struct sctp_association *asoc,
246 			    struct sctp_chunk *chunk)
247 {
248 	struct net *net = sock_net(asoc->base.sk);
249 	int retval = 0;
250 
251 	retval = sctp_primitive_RECONF(net, asoc, chunk);
252 	if (retval)
253 		sctp_chunk_free(chunk);
254 
255 	return retval;
256 }
257 
258 static bool sctp_stream_outq_is_empty(struct sctp_stream *stream,
259 				      __u16 str_nums, __be16 *str_list)
260 {
261 	struct sctp_association *asoc;
262 	__u16 i;
263 
264 	asoc = container_of(stream, struct sctp_association, stream);
265 	if (!asoc->outqueue.out_qlen)
266 		return true;
267 
268 	if (!str_nums)
269 		return false;
270 
271 	for (i = 0; i < str_nums; i++) {
272 		__u16 sid = ntohs(str_list[i]);
273 
274 		if (stream->out[sid].ext &&
275 		    !list_empty(&stream->out[sid].ext->outq))
276 			return false;
277 	}
278 
279 	return true;
280 }
281 
282 int sctp_send_reset_streams(struct sctp_association *asoc,
283 			    struct sctp_reset_streams *params)
284 {
285 	struct sctp_stream *stream = &asoc->stream;
286 	__u16 i, str_nums, *str_list;
287 	struct sctp_chunk *chunk;
288 	int retval = -EINVAL;
289 	__be16 *nstr_list;
290 	bool out, in;
291 
292 	if (!asoc->peer.reconf_capable ||
293 	    !(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ)) {
294 		retval = -ENOPROTOOPT;
295 		goto out;
296 	}
297 
298 	if (asoc->strreset_outstanding) {
299 		retval = -EINPROGRESS;
300 		goto out;
301 	}
302 
303 	out = params->srs_flags & SCTP_STREAM_RESET_OUTGOING;
304 	in  = params->srs_flags & SCTP_STREAM_RESET_INCOMING;
305 	if (!out && !in)
306 		goto out;
307 
308 	str_nums = params->srs_number_streams;
309 	str_list = params->srs_stream_list;
310 	if (str_nums) {
311 		int param_len = 0;
312 
313 		if (out) {
314 			for (i = 0; i < str_nums; i++)
315 				if (str_list[i] >= stream->outcnt)
316 					goto out;
317 
318 			param_len = str_nums * sizeof(__u16) +
319 				    sizeof(struct sctp_strreset_outreq);
320 		}
321 
322 		if (in) {
323 			for (i = 0; i < str_nums; i++)
324 				if (str_list[i] >= stream->incnt)
325 					goto out;
326 
327 			param_len += str_nums * sizeof(__u16) +
328 				     sizeof(struct sctp_strreset_inreq);
329 		}
330 
331 		if (param_len > SCTP_MAX_CHUNK_LEN -
332 				sizeof(struct sctp_reconf_chunk))
333 			goto out;
334 	}
335 
336 	nstr_list = kcalloc(str_nums, sizeof(__be16), GFP_KERNEL);
337 	if (!nstr_list) {
338 		retval = -ENOMEM;
339 		goto out;
340 	}
341 
342 	for (i = 0; i < str_nums; i++)
343 		nstr_list[i] = htons(str_list[i]);
344 
345 	if (out && !sctp_stream_outq_is_empty(stream, str_nums, nstr_list)) {
346 		retval = -EAGAIN;
347 		goto out;
348 	}
349 
350 	chunk = sctp_make_strreset_req(asoc, str_nums, nstr_list, out, in);
351 
352 	kfree(nstr_list);
353 
354 	if (!chunk) {
355 		retval = -ENOMEM;
356 		goto out;
357 	}
358 
359 	if (out) {
360 		if (str_nums)
361 			for (i = 0; i < str_nums; i++)
362 				stream->out[str_list[i]].state =
363 						       SCTP_STREAM_CLOSED;
364 		else
365 			for (i = 0; i < stream->outcnt; i++)
366 				stream->out[i].state = SCTP_STREAM_CLOSED;
367 	}
368 
369 	asoc->strreset_chunk = chunk;
370 	sctp_chunk_hold(asoc->strreset_chunk);
371 
372 	retval = sctp_send_reconf(asoc, chunk);
373 	if (retval) {
374 		sctp_chunk_put(asoc->strreset_chunk);
375 		asoc->strreset_chunk = NULL;
376 		if (!out)
377 			goto out;
378 
379 		if (str_nums)
380 			for (i = 0; i < str_nums; i++)
381 				stream->out[str_list[i]].state =
382 						       SCTP_STREAM_OPEN;
383 		else
384 			for (i = 0; i < stream->outcnt; i++)
385 				stream->out[i].state = SCTP_STREAM_OPEN;
386 
387 		goto out;
388 	}
389 
390 	asoc->strreset_outstanding = out + in;
391 
392 out:
393 	return retval;
394 }
395 
396 int sctp_send_reset_assoc(struct sctp_association *asoc)
397 {
398 	struct sctp_stream *stream = &asoc->stream;
399 	struct sctp_chunk *chunk = NULL;
400 	int retval;
401 	__u16 i;
402 
403 	if (!asoc->peer.reconf_capable ||
404 	    !(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
405 		return -ENOPROTOOPT;
406 
407 	if (asoc->strreset_outstanding)
408 		return -EINPROGRESS;
409 
410 	if (!sctp_outq_is_empty(&asoc->outqueue))
411 		return -EAGAIN;
412 
413 	chunk = sctp_make_strreset_tsnreq(asoc);
414 	if (!chunk)
415 		return -ENOMEM;
416 
417 	/* Block further xmit of data until this request is completed */
418 	for (i = 0; i < stream->outcnt; i++)
419 		stream->out[i].state = SCTP_STREAM_CLOSED;
420 
421 	asoc->strreset_chunk = chunk;
422 	sctp_chunk_hold(asoc->strreset_chunk);
423 
424 	retval = sctp_send_reconf(asoc, chunk);
425 	if (retval) {
426 		sctp_chunk_put(asoc->strreset_chunk);
427 		asoc->strreset_chunk = NULL;
428 
429 		for (i = 0; i < stream->outcnt; i++)
430 			stream->out[i].state = SCTP_STREAM_OPEN;
431 
432 		return retval;
433 	}
434 
435 	asoc->strreset_outstanding = 1;
436 
437 	return 0;
438 }
439 
440 int sctp_send_add_streams(struct sctp_association *asoc,
441 			  struct sctp_add_streams *params)
442 {
443 	struct sctp_stream *stream = &asoc->stream;
444 	struct sctp_chunk *chunk = NULL;
445 	int retval;
446 	__u32 outcnt, incnt;
447 	__u16 out, in;
448 
449 	if (!asoc->peer.reconf_capable ||
450 	    !(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ)) {
451 		retval = -ENOPROTOOPT;
452 		goto out;
453 	}
454 
455 	if (asoc->strreset_outstanding) {
456 		retval = -EINPROGRESS;
457 		goto out;
458 	}
459 
460 	out = params->sas_outstrms;
461 	in  = params->sas_instrms;
462 	outcnt = stream->outcnt + out;
463 	incnt = stream->incnt + in;
464 	if (outcnt > SCTP_MAX_STREAM || incnt > SCTP_MAX_STREAM ||
465 	    (!out && !in)) {
466 		retval = -EINVAL;
467 		goto out;
468 	}
469 
470 	if (out) {
471 		retval = sctp_stream_alloc_out(stream, outcnt, GFP_KERNEL);
472 		if (retval)
473 			goto out;
474 	}
475 
476 	chunk = sctp_make_strreset_addstrm(asoc, out, in);
477 	if (!chunk) {
478 		retval = -ENOMEM;
479 		goto out;
480 	}
481 
482 	asoc->strreset_chunk = chunk;
483 	sctp_chunk_hold(asoc->strreset_chunk);
484 
485 	retval = sctp_send_reconf(asoc, chunk);
486 	if (retval) {
487 		sctp_chunk_put(asoc->strreset_chunk);
488 		asoc->strreset_chunk = NULL;
489 		goto out;
490 	}
491 
492 	stream->incnt = incnt;
493 	stream->outcnt = outcnt;
494 
495 	asoc->strreset_outstanding = !!out + !!in;
496 
497 out:
498 	return retval;
499 }
500 
501 static struct sctp_paramhdr *sctp_chunk_lookup_strreset_param(
502 			struct sctp_association *asoc, __be32 resp_seq,
503 			__be16 type)
504 {
505 	struct sctp_chunk *chunk = asoc->strreset_chunk;
506 	struct sctp_reconf_chunk *hdr;
507 	union sctp_params param;
508 
509 	if (!chunk)
510 		return NULL;
511 
512 	hdr = (struct sctp_reconf_chunk *)chunk->chunk_hdr;
513 	sctp_walk_params(param, hdr, params) {
514 		/* sctp_strreset_tsnreq is actually the basic structure
515 		 * of all stream reconf params, so it's safe to use it
516 		 * to access request_seq.
517 		 */
518 		struct sctp_strreset_tsnreq *req = param.v;
519 
520 		if ((!resp_seq || req->request_seq == resp_seq) &&
521 		    (!type || type == req->param_hdr.type))
522 			return param.v;
523 	}
524 
525 	return NULL;
526 }
527 
528 static void sctp_update_strreset_result(struct sctp_association *asoc,
529 					__u32 result)
530 {
531 	asoc->strreset_result[1] = asoc->strreset_result[0];
532 	asoc->strreset_result[0] = result;
533 }
534 
535 struct sctp_chunk *sctp_process_strreset_outreq(
536 				struct sctp_association *asoc,
537 				union sctp_params param,
538 				struct sctp_ulpevent **evp)
539 {
540 	struct sctp_strreset_outreq *outreq = param.v;
541 	struct sctp_stream *stream = &asoc->stream;
542 	__u32 result = SCTP_STRRESET_DENIED;
543 	__u16 i, nums, flags = 0;
544 	__be16 *str_p = NULL;
545 	__u32 request_seq;
546 
547 	request_seq = ntohl(outreq->request_seq);
548 
549 	if (ntohl(outreq->send_reset_at_tsn) >
550 	    sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map)) {
551 		result = SCTP_STRRESET_IN_PROGRESS;
552 		goto err;
553 	}
554 
555 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
556 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
557 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
558 		goto err;
559 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
560 		i = asoc->strreset_inseq - request_seq - 1;
561 		result = asoc->strreset_result[i];
562 		goto err;
563 	}
564 	asoc->strreset_inseq++;
565 
566 	/* Check strreset_enable after inseq inc, as sender cannot tell
567 	 * the peer doesn't enable strreset after receiving response with
568 	 * result denied, as well as to keep consistent with bsd.
569 	 */
570 	if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
571 		goto out;
572 
573 	if (asoc->strreset_chunk) {
574 		if (!sctp_chunk_lookup_strreset_param(
575 				asoc, outreq->response_seq,
576 				SCTP_PARAM_RESET_IN_REQUEST)) {
577 			/* same process with outstanding isn't 0 */
578 			result = SCTP_STRRESET_ERR_IN_PROGRESS;
579 			goto out;
580 		}
581 
582 		asoc->strreset_outstanding--;
583 		asoc->strreset_outseq++;
584 
585 		if (!asoc->strreset_outstanding) {
586 			struct sctp_transport *t;
587 
588 			t = asoc->strreset_chunk->transport;
589 			if (del_timer(&t->reconf_timer))
590 				sctp_transport_put(t);
591 
592 			sctp_chunk_put(asoc->strreset_chunk);
593 			asoc->strreset_chunk = NULL;
594 		}
595 
596 		flags = SCTP_STREAM_RESET_INCOMING_SSN;
597 	}
598 
599 	nums = (ntohs(param.p->length) - sizeof(*outreq)) / sizeof(__u16);
600 	if (nums) {
601 		str_p = outreq->list_of_streams;
602 		for (i = 0; i < nums; i++) {
603 			if (ntohs(str_p[i]) >= stream->incnt) {
604 				result = SCTP_STRRESET_ERR_WRONG_SSN;
605 				goto out;
606 			}
607 		}
608 
609 		for (i = 0; i < nums; i++)
610 			stream->in[ntohs(str_p[i])].mid = 0;
611 	} else {
612 		for (i = 0; i < stream->incnt; i++)
613 			stream->in[i].mid = 0;
614 	}
615 
616 	result = SCTP_STRRESET_PERFORMED;
617 
618 	*evp = sctp_ulpevent_make_stream_reset_event(asoc,
619 		flags | SCTP_STREAM_RESET_OUTGOING_SSN, nums, str_p,
620 		GFP_ATOMIC);
621 
622 out:
623 	sctp_update_strreset_result(asoc, result);
624 err:
625 	return sctp_make_strreset_resp(asoc, result, request_seq);
626 }
627 
628 struct sctp_chunk *sctp_process_strreset_inreq(
629 				struct sctp_association *asoc,
630 				union sctp_params param,
631 				struct sctp_ulpevent **evp)
632 {
633 	struct sctp_strreset_inreq *inreq = param.v;
634 	struct sctp_stream *stream = &asoc->stream;
635 	__u32 result = SCTP_STRRESET_DENIED;
636 	struct sctp_chunk *chunk = NULL;
637 	__u32 request_seq;
638 	__u16 i, nums;
639 	__be16 *str_p;
640 
641 	request_seq = ntohl(inreq->request_seq);
642 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
643 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
644 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
645 		goto err;
646 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
647 		i = asoc->strreset_inseq - request_seq - 1;
648 		result = asoc->strreset_result[i];
649 		if (result == SCTP_STRRESET_PERFORMED)
650 			return NULL;
651 		goto err;
652 	}
653 	asoc->strreset_inseq++;
654 
655 	if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
656 		goto out;
657 
658 	if (asoc->strreset_outstanding) {
659 		result = SCTP_STRRESET_ERR_IN_PROGRESS;
660 		goto out;
661 	}
662 
663 	nums = (ntohs(param.p->length) - sizeof(*inreq)) / sizeof(__u16);
664 	str_p = inreq->list_of_streams;
665 	for (i = 0; i < nums; i++) {
666 		if (ntohs(str_p[i]) >= stream->outcnt) {
667 			result = SCTP_STRRESET_ERR_WRONG_SSN;
668 			goto out;
669 		}
670 	}
671 
672 	if (!sctp_stream_outq_is_empty(stream, nums, str_p)) {
673 		result = SCTP_STRRESET_IN_PROGRESS;
674 		asoc->strreset_inseq--;
675 		goto err;
676 	}
677 
678 	chunk = sctp_make_strreset_req(asoc, nums, str_p, 1, 0);
679 	if (!chunk)
680 		goto out;
681 
682 	if (nums)
683 		for (i = 0; i < nums; i++)
684 			stream->out[ntohs(str_p[i])].state =
685 					       SCTP_STREAM_CLOSED;
686 	else
687 		for (i = 0; i < stream->outcnt; i++)
688 			stream->out[i].state = SCTP_STREAM_CLOSED;
689 
690 	asoc->strreset_chunk = chunk;
691 	asoc->strreset_outstanding = 1;
692 	sctp_chunk_hold(asoc->strreset_chunk);
693 
694 	result = SCTP_STRRESET_PERFORMED;
695 
696 	*evp = sctp_ulpevent_make_stream_reset_event(asoc,
697 		SCTP_STREAM_RESET_INCOMING_SSN, nums, str_p, GFP_ATOMIC);
698 
699 out:
700 	sctp_update_strreset_result(asoc, result);
701 err:
702 	if (!chunk)
703 		chunk =  sctp_make_strreset_resp(asoc, result, request_seq);
704 
705 	return chunk;
706 }
707 
708 struct sctp_chunk *sctp_process_strreset_tsnreq(
709 				struct sctp_association *asoc,
710 				union sctp_params param,
711 				struct sctp_ulpevent **evp)
712 {
713 	__u32 init_tsn = 0, next_tsn = 0, max_tsn_seen;
714 	struct sctp_strreset_tsnreq *tsnreq = param.v;
715 	struct sctp_stream *stream = &asoc->stream;
716 	__u32 result = SCTP_STRRESET_DENIED;
717 	__u32 request_seq;
718 	__u16 i;
719 
720 	request_seq = ntohl(tsnreq->request_seq);
721 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
722 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
723 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
724 		goto err;
725 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
726 		i = asoc->strreset_inseq - request_seq - 1;
727 		result = asoc->strreset_result[i];
728 		if (result == SCTP_STRRESET_PERFORMED) {
729 			next_tsn = asoc->ctsn_ack_point + 1;
730 			init_tsn =
731 				sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + 1;
732 		}
733 		goto err;
734 	}
735 
736 	if (!sctp_outq_is_empty(&asoc->outqueue)) {
737 		result = SCTP_STRRESET_IN_PROGRESS;
738 		goto err;
739 	}
740 
741 	asoc->strreset_inseq++;
742 
743 	if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
744 		goto out;
745 
746 	if (asoc->strreset_outstanding) {
747 		result = SCTP_STRRESET_ERR_IN_PROGRESS;
748 		goto out;
749 	}
750 
751 	/* G4: The same processing as though a FWD-TSN chunk (as defined in
752 	 *     [RFC3758]) with all streams affected and a new cumulative TSN
753 	 *     ACK of the Receiver's Next TSN minus 1 were received MUST be
754 	 *     performed.
755 	 */
756 	max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
757 	asoc->stream.si->report_ftsn(&asoc->ulpq, max_tsn_seen);
758 
759 	/* G1: Compute an appropriate value for the Receiver's Next TSN -- the
760 	 *     TSN that the peer should use to send the next DATA chunk.  The
761 	 *     value SHOULD be the smallest TSN not acknowledged by the
762 	 *     receiver of the request plus 2^31.
763 	 */
764 	init_tsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + (1 << 31);
765 	sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
766 			 init_tsn, GFP_ATOMIC);
767 
768 	/* G3: The same processing as though a SACK chunk with no gap report
769 	 *     and a cumulative TSN ACK of the Sender's Next TSN minus 1 were
770 	 *     received MUST be performed.
771 	 */
772 	sctp_outq_free(&asoc->outqueue);
773 
774 	/* G2: Compute an appropriate value for the local endpoint's next TSN,
775 	 *     i.e., the next TSN assigned by the receiver of the SSN/TSN reset
776 	 *     chunk.  The value SHOULD be the highest TSN sent by the receiver
777 	 *     of the request plus 1.
778 	 */
779 	next_tsn = asoc->next_tsn;
780 	asoc->ctsn_ack_point = next_tsn - 1;
781 	asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
782 
783 	/* G5:  The next expected and outgoing SSNs MUST be reset to 0 for all
784 	 *      incoming and outgoing streams.
785 	 */
786 	for (i = 0; i < stream->outcnt; i++) {
787 		stream->out[i].mid = 0;
788 		stream->out[i].mid_uo = 0;
789 	}
790 	for (i = 0; i < stream->incnt; i++)
791 		stream->in[i].mid = 0;
792 
793 	result = SCTP_STRRESET_PERFORMED;
794 
795 	*evp = sctp_ulpevent_make_assoc_reset_event(asoc, 0, init_tsn,
796 						    next_tsn, GFP_ATOMIC);
797 
798 out:
799 	sctp_update_strreset_result(asoc, result);
800 err:
801 	return sctp_make_strreset_tsnresp(asoc, result, request_seq,
802 					  next_tsn, init_tsn);
803 }
804 
805 struct sctp_chunk *sctp_process_strreset_addstrm_out(
806 				struct sctp_association *asoc,
807 				union sctp_params param,
808 				struct sctp_ulpevent **evp)
809 {
810 	struct sctp_strreset_addstrm *addstrm = param.v;
811 	struct sctp_stream *stream = &asoc->stream;
812 	__u32 result = SCTP_STRRESET_DENIED;
813 	__u32 request_seq, incnt;
814 	__u16 in, i;
815 
816 	request_seq = ntohl(addstrm->request_seq);
817 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
818 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
819 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
820 		goto err;
821 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
822 		i = asoc->strreset_inseq - request_seq - 1;
823 		result = asoc->strreset_result[i];
824 		goto err;
825 	}
826 	asoc->strreset_inseq++;
827 
828 	if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
829 		goto out;
830 
831 	if (asoc->strreset_chunk) {
832 		if (!sctp_chunk_lookup_strreset_param(
833 			asoc, 0, SCTP_PARAM_RESET_ADD_IN_STREAMS)) {
834 			/* same process with outstanding isn't 0 */
835 			result = SCTP_STRRESET_ERR_IN_PROGRESS;
836 			goto out;
837 		}
838 
839 		asoc->strreset_outstanding--;
840 		asoc->strreset_outseq++;
841 
842 		if (!asoc->strreset_outstanding) {
843 			struct sctp_transport *t;
844 
845 			t = asoc->strreset_chunk->transport;
846 			if (del_timer(&t->reconf_timer))
847 				sctp_transport_put(t);
848 
849 			sctp_chunk_put(asoc->strreset_chunk);
850 			asoc->strreset_chunk = NULL;
851 		}
852 	}
853 
854 	in = ntohs(addstrm->number_of_streams);
855 	incnt = stream->incnt + in;
856 	if (!in || incnt > SCTP_MAX_STREAM)
857 		goto out;
858 
859 	if (sctp_stream_alloc_in(stream, incnt, GFP_ATOMIC))
860 		goto out;
861 
862 	stream->incnt = incnt;
863 
864 	result = SCTP_STRRESET_PERFORMED;
865 
866 	*evp = sctp_ulpevent_make_stream_change_event(asoc,
867 		0, ntohs(addstrm->number_of_streams), 0, GFP_ATOMIC);
868 
869 out:
870 	sctp_update_strreset_result(asoc, result);
871 err:
872 	return sctp_make_strreset_resp(asoc, result, request_seq);
873 }
874 
875 struct sctp_chunk *sctp_process_strreset_addstrm_in(
876 				struct sctp_association *asoc,
877 				union sctp_params param,
878 				struct sctp_ulpevent **evp)
879 {
880 	struct sctp_strreset_addstrm *addstrm = param.v;
881 	struct sctp_stream *stream = &asoc->stream;
882 	__u32 result = SCTP_STRRESET_DENIED;
883 	struct sctp_chunk *chunk = NULL;
884 	__u32 request_seq, outcnt;
885 	__u16 out, i;
886 	int ret;
887 
888 	request_seq = ntohl(addstrm->request_seq);
889 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
890 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
891 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
892 		goto err;
893 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
894 		i = asoc->strreset_inseq - request_seq - 1;
895 		result = asoc->strreset_result[i];
896 		if (result == SCTP_STRRESET_PERFORMED)
897 			return NULL;
898 		goto err;
899 	}
900 	asoc->strreset_inseq++;
901 
902 	if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
903 		goto out;
904 
905 	if (asoc->strreset_outstanding) {
906 		result = SCTP_STRRESET_ERR_IN_PROGRESS;
907 		goto out;
908 	}
909 
910 	out = ntohs(addstrm->number_of_streams);
911 	outcnt = stream->outcnt + out;
912 	if (!out || outcnt > SCTP_MAX_STREAM)
913 		goto out;
914 
915 	ret = sctp_stream_alloc_out(stream, outcnt, GFP_ATOMIC);
916 	if (ret)
917 		goto out;
918 
919 	chunk = sctp_make_strreset_addstrm(asoc, out, 0);
920 	if (!chunk)
921 		goto out;
922 
923 	asoc->strreset_chunk = chunk;
924 	asoc->strreset_outstanding = 1;
925 	sctp_chunk_hold(asoc->strreset_chunk);
926 
927 	stream->outcnt = outcnt;
928 
929 	result = SCTP_STRRESET_PERFORMED;
930 
931 	*evp = sctp_ulpevent_make_stream_change_event(asoc,
932 		0, 0, ntohs(addstrm->number_of_streams), GFP_ATOMIC);
933 
934 out:
935 	sctp_update_strreset_result(asoc, result);
936 err:
937 	if (!chunk)
938 		chunk = sctp_make_strreset_resp(asoc, result, request_seq);
939 
940 	return chunk;
941 }
942 
943 struct sctp_chunk *sctp_process_strreset_resp(
944 				struct sctp_association *asoc,
945 				union sctp_params param,
946 				struct sctp_ulpevent **evp)
947 {
948 	struct sctp_stream *stream = &asoc->stream;
949 	struct sctp_strreset_resp *resp = param.v;
950 	struct sctp_transport *t;
951 	__u16 i, nums, flags = 0;
952 	struct sctp_paramhdr *req;
953 	__u32 result;
954 
955 	req = sctp_chunk_lookup_strreset_param(asoc, resp->response_seq, 0);
956 	if (!req)
957 		return NULL;
958 
959 	result = ntohl(resp->result);
960 	if (result != SCTP_STRRESET_PERFORMED) {
961 		/* if in progress, do nothing but retransmit */
962 		if (result == SCTP_STRRESET_IN_PROGRESS)
963 			return NULL;
964 		else if (result == SCTP_STRRESET_DENIED)
965 			flags = SCTP_STREAM_RESET_DENIED;
966 		else
967 			flags = SCTP_STREAM_RESET_FAILED;
968 	}
969 
970 	if (req->type == SCTP_PARAM_RESET_OUT_REQUEST) {
971 		struct sctp_strreset_outreq *outreq;
972 		__be16 *str_p;
973 
974 		outreq = (struct sctp_strreset_outreq *)req;
975 		str_p = outreq->list_of_streams;
976 		nums = (ntohs(outreq->param_hdr.length) - sizeof(*outreq)) /
977 		       sizeof(__u16);
978 
979 		if (result == SCTP_STRRESET_PERFORMED) {
980 			if (nums) {
981 				for (i = 0; i < nums; i++) {
982 					stream->out[ntohs(str_p[i])].mid = 0;
983 					stream->out[ntohs(str_p[i])].mid_uo = 0;
984 				}
985 			} else {
986 				for (i = 0; i < stream->outcnt; i++) {
987 					stream->out[i].mid = 0;
988 					stream->out[i].mid_uo = 0;
989 				}
990 			}
991 
992 			flags = SCTP_STREAM_RESET_OUTGOING_SSN;
993 		}
994 
995 		for (i = 0; i < stream->outcnt; i++)
996 			stream->out[i].state = SCTP_STREAM_OPEN;
997 
998 		*evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
999 			nums, str_p, GFP_ATOMIC);
1000 	} else if (req->type == SCTP_PARAM_RESET_IN_REQUEST) {
1001 		struct sctp_strreset_inreq *inreq;
1002 		__be16 *str_p;
1003 
1004 		/* if the result is performed, it's impossible for inreq */
1005 		if (result == SCTP_STRRESET_PERFORMED)
1006 			return NULL;
1007 
1008 		inreq = (struct sctp_strreset_inreq *)req;
1009 		str_p = inreq->list_of_streams;
1010 		nums = (ntohs(inreq->param_hdr.length) - sizeof(*inreq)) /
1011 		       sizeof(__u16);
1012 
1013 		*evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
1014 			nums, str_p, GFP_ATOMIC);
1015 	} else if (req->type == SCTP_PARAM_RESET_TSN_REQUEST) {
1016 		struct sctp_strreset_resptsn *resptsn;
1017 		__u32 stsn, rtsn;
1018 
1019 		/* check for resptsn, as sctp_verify_reconf didn't do it*/
1020 		if (ntohs(param.p->length) != sizeof(*resptsn))
1021 			return NULL;
1022 
1023 		resptsn = (struct sctp_strreset_resptsn *)resp;
1024 		stsn = ntohl(resptsn->senders_next_tsn);
1025 		rtsn = ntohl(resptsn->receivers_next_tsn);
1026 
1027 		if (result == SCTP_STRRESET_PERFORMED) {
1028 			__u32 mtsn = sctp_tsnmap_get_max_tsn_seen(
1029 						&asoc->peer.tsn_map);
1030 			LIST_HEAD(temp);
1031 
1032 			asoc->stream.si->report_ftsn(&asoc->ulpq, mtsn);
1033 
1034 			sctp_tsnmap_init(&asoc->peer.tsn_map,
1035 					 SCTP_TSN_MAP_INITIAL,
1036 					 stsn, GFP_ATOMIC);
1037 
1038 			/* Clean up sacked and abandoned queues only. As the
1039 			 * out_chunk_list may not be empty, splice it to temp,
1040 			 * then get it back after sctp_outq_free is done.
1041 			 */
1042 			list_splice_init(&asoc->outqueue.out_chunk_list, &temp);
1043 			sctp_outq_free(&asoc->outqueue);
1044 			list_splice_init(&temp, &asoc->outqueue.out_chunk_list);
1045 
1046 			asoc->next_tsn = rtsn;
1047 			asoc->ctsn_ack_point = asoc->next_tsn - 1;
1048 			asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
1049 
1050 			for (i = 0; i < stream->outcnt; i++) {
1051 				stream->out[i].mid = 0;
1052 				stream->out[i].mid_uo = 0;
1053 			}
1054 			for (i = 0; i < stream->incnt; i++)
1055 				stream->in[i].mid = 0;
1056 		}
1057 
1058 		for (i = 0; i < stream->outcnt; i++)
1059 			stream->out[i].state = SCTP_STREAM_OPEN;
1060 
1061 		*evp = sctp_ulpevent_make_assoc_reset_event(asoc, flags,
1062 			stsn, rtsn, GFP_ATOMIC);
1063 	} else if (req->type == SCTP_PARAM_RESET_ADD_OUT_STREAMS) {
1064 		struct sctp_strreset_addstrm *addstrm;
1065 		__u16 number;
1066 
1067 		addstrm = (struct sctp_strreset_addstrm *)req;
1068 		nums = ntohs(addstrm->number_of_streams);
1069 		number = stream->outcnt - nums;
1070 
1071 		if (result == SCTP_STRRESET_PERFORMED)
1072 			for (i = number; i < stream->outcnt; i++)
1073 				stream->out[i].state = SCTP_STREAM_OPEN;
1074 		else
1075 			stream->outcnt = number;
1076 
1077 		*evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1078 			0, nums, GFP_ATOMIC);
1079 	} else if (req->type == SCTP_PARAM_RESET_ADD_IN_STREAMS) {
1080 		struct sctp_strreset_addstrm *addstrm;
1081 
1082 		/* if the result is performed, it's impossible for addstrm in
1083 		 * request.
1084 		 */
1085 		if (result == SCTP_STRRESET_PERFORMED)
1086 			return NULL;
1087 
1088 		addstrm = (struct sctp_strreset_addstrm *)req;
1089 		nums = ntohs(addstrm->number_of_streams);
1090 
1091 		*evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1092 			nums, 0, GFP_ATOMIC);
1093 	}
1094 
1095 	asoc->strreset_outstanding--;
1096 	asoc->strreset_outseq++;
1097 
1098 	/* remove everything for this reconf request */
1099 	if (!asoc->strreset_outstanding) {
1100 		t = asoc->strreset_chunk->transport;
1101 		if (del_timer(&t->reconf_timer))
1102 			sctp_transport_put(t);
1103 
1104 		sctp_chunk_put(asoc->strreset_chunk);
1105 		asoc->strreset_chunk = NULL;
1106 	}
1107 
1108 	return NULL;
1109 }
1110