xref: /openbmc/linux/net/sctp/stream.c (revision 6724ed7f)
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 	i = sctp_stream_alloc_out(stream, outcnt, gfp);
160 	if (i)
161 		return i;
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 	i = sctp_stream_alloc_in(stream, incnt, gfp);
174 	if (i) {
175 		ret = -ENOMEM;
176 		goto free;
177 	}
178 
179 	stream->incnt = incnt;
180 	goto out;
181 
182 free:
183 	sched->free(stream);
184 	kfree(stream->out);
185 	stream->out = NULL;
186 out:
187 	return ret;
188 }
189 
190 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid)
191 {
192 	struct sctp_stream_out_ext *soute;
193 
194 	soute = kzalloc(sizeof(*soute), GFP_KERNEL);
195 	if (!soute)
196 		return -ENOMEM;
197 	stream->out[sid].ext = soute;
198 
199 	return sctp_sched_init_sid(stream, sid, GFP_KERNEL);
200 }
201 
202 void sctp_stream_free(struct sctp_stream *stream)
203 {
204 	struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
205 	int i;
206 
207 	sched->free(stream);
208 	for (i = 0; i < stream->outcnt; i++)
209 		kfree(stream->out[i].ext);
210 	kfree(stream->out);
211 	kfree(stream->in);
212 }
213 
214 void sctp_stream_clear(struct sctp_stream *stream)
215 {
216 	int i;
217 
218 	for (i = 0; i < stream->outcnt; i++)
219 		stream->out[i].ssn = 0;
220 
221 	for (i = 0; i < stream->incnt; i++)
222 		stream->in[i].ssn = 0;
223 }
224 
225 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new)
226 {
227 	struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
228 
229 	sched->unsched_all(stream);
230 	sctp_stream_outq_migrate(stream, new, new->outcnt);
231 	sctp_stream_free(stream);
232 
233 	stream->out = new->out;
234 	stream->in  = new->in;
235 	stream->outcnt = new->outcnt;
236 	stream->incnt  = new->incnt;
237 
238 	sched->sched_all(stream);
239 
240 	new->out = NULL;
241 	new->in  = NULL;
242 }
243 
244 static int sctp_send_reconf(struct sctp_association *asoc,
245 			    struct sctp_chunk *chunk)
246 {
247 	struct net *net = sock_net(asoc->base.sk);
248 	int retval = 0;
249 
250 	retval = sctp_primitive_RECONF(net, asoc, chunk);
251 	if (retval)
252 		sctp_chunk_free(chunk);
253 
254 	return retval;
255 }
256 
257 static bool sctp_stream_outq_is_empty(struct sctp_stream *stream,
258 				      __u16 str_nums, __be16 *str_list)
259 {
260 	struct sctp_association *asoc;
261 	__u16 i;
262 
263 	asoc = container_of(stream, struct sctp_association, stream);
264 	if (!asoc->outqueue.out_qlen)
265 		return true;
266 
267 	if (!str_nums)
268 		return false;
269 
270 	for (i = 0; i < str_nums; i++) {
271 		__u16 sid = ntohs(str_list[i]);
272 
273 		if (stream->out[sid].ext &&
274 		    !list_empty(&stream->out[sid].ext->outq))
275 			return false;
276 	}
277 
278 	return true;
279 }
280 
281 int sctp_send_reset_streams(struct sctp_association *asoc,
282 			    struct sctp_reset_streams *params)
283 {
284 	struct sctp_stream *stream = &asoc->stream;
285 	__u16 i, str_nums, *str_list;
286 	struct sctp_chunk *chunk;
287 	int retval = -EINVAL;
288 	__be16 *nstr_list;
289 	bool out, in;
290 
291 	if (!asoc->peer.reconf_capable ||
292 	    !(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ)) {
293 		retval = -ENOPROTOOPT;
294 		goto out;
295 	}
296 
297 	if (asoc->strreset_outstanding) {
298 		retval = -EINPROGRESS;
299 		goto out;
300 	}
301 
302 	out = params->srs_flags & SCTP_STREAM_RESET_OUTGOING;
303 	in  = params->srs_flags & SCTP_STREAM_RESET_INCOMING;
304 	if (!out && !in)
305 		goto out;
306 
307 	str_nums = params->srs_number_streams;
308 	str_list = params->srs_stream_list;
309 	if (str_nums) {
310 		int param_len = 0;
311 
312 		if (out) {
313 			for (i = 0; i < str_nums; i++)
314 				if (str_list[i] >= stream->outcnt)
315 					goto out;
316 
317 			param_len = str_nums * sizeof(__u16) +
318 				    sizeof(struct sctp_strreset_outreq);
319 		}
320 
321 		if (in) {
322 			for (i = 0; i < str_nums; i++)
323 				if (str_list[i] >= stream->incnt)
324 					goto out;
325 
326 			param_len += str_nums * sizeof(__u16) +
327 				     sizeof(struct sctp_strreset_inreq);
328 		}
329 
330 		if (param_len > SCTP_MAX_CHUNK_LEN -
331 				sizeof(struct sctp_reconf_chunk))
332 			goto out;
333 	}
334 
335 	nstr_list = kcalloc(str_nums, sizeof(__be16), GFP_KERNEL);
336 	if (!nstr_list) {
337 		retval = -ENOMEM;
338 		goto out;
339 	}
340 
341 	for (i = 0; i < str_nums; i++)
342 		nstr_list[i] = htons(str_list[i]);
343 
344 	if (out && !sctp_stream_outq_is_empty(stream, str_nums, nstr_list)) {
345 		retval = -EAGAIN;
346 		goto out;
347 	}
348 
349 	chunk = sctp_make_strreset_req(asoc, str_nums, nstr_list, out, in);
350 
351 	kfree(nstr_list);
352 
353 	if (!chunk) {
354 		retval = -ENOMEM;
355 		goto out;
356 	}
357 
358 	if (out) {
359 		if (str_nums)
360 			for (i = 0; i < str_nums; i++)
361 				stream->out[str_list[i]].state =
362 						       SCTP_STREAM_CLOSED;
363 		else
364 			for (i = 0; i < stream->outcnt; i++)
365 				stream->out[i].state = SCTP_STREAM_CLOSED;
366 	}
367 
368 	asoc->strreset_chunk = chunk;
369 	sctp_chunk_hold(asoc->strreset_chunk);
370 
371 	retval = sctp_send_reconf(asoc, chunk);
372 	if (retval) {
373 		sctp_chunk_put(asoc->strreset_chunk);
374 		asoc->strreset_chunk = NULL;
375 		if (!out)
376 			goto out;
377 
378 		if (str_nums)
379 			for (i = 0; i < str_nums; i++)
380 				stream->out[str_list[i]].state =
381 						       SCTP_STREAM_OPEN;
382 		else
383 			for (i = 0; i < stream->outcnt; i++)
384 				stream->out[i].state = SCTP_STREAM_OPEN;
385 
386 		goto out;
387 	}
388 
389 	asoc->strreset_outstanding = out + in;
390 
391 out:
392 	return retval;
393 }
394 
395 int sctp_send_reset_assoc(struct sctp_association *asoc)
396 {
397 	struct sctp_stream *stream = &asoc->stream;
398 	struct sctp_chunk *chunk = NULL;
399 	int retval;
400 	__u16 i;
401 
402 	if (!asoc->peer.reconf_capable ||
403 	    !(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
404 		return -ENOPROTOOPT;
405 
406 	if (asoc->strreset_outstanding)
407 		return -EINPROGRESS;
408 
409 	if (!sctp_outq_is_empty(&asoc->outqueue))
410 		return -EAGAIN;
411 
412 	chunk = sctp_make_strreset_tsnreq(asoc);
413 	if (!chunk)
414 		return -ENOMEM;
415 
416 	/* Block further xmit of data until this request is completed */
417 	for (i = 0; i < stream->outcnt; i++)
418 		stream->out[i].state = SCTP_STREAM_CLOSED;
419 
420 	asoc->strreset_chunk = chunk;
421 	sctp_chunk_hold(asoc->strreset_chunk);
422 
423 	retval = sctp_send_reconf(asoc, chunk);
424 	if (retval) {
425 		sctp_chunk_put(asoc->strreset_chunk);
426 		asoc->strreset_chunk = NULL;
427 
428 		for (i = 0; i < stream->outcnt; i++)
429 			stream->out[i].state = SCTP_STREAM_OPEN;
430 
431 		return retval;
432 	}
433 
434 	asoc->strreset_outstanding = 1;
435 
436 	return 0;
437 }
438 
439 int sctp_send_add_streams(struct sctp_association *asoc,
440 			  struct sctp_add_streams *params)
441 {
442 	struct sctp_stream *stream = &asoc->stream;
443 	struct sctp_chunk *chunk = NULL;
444 	int retval;
445 	__u32 outcnt, incnt;
446 	__u16 out, in;
447 
448 	if (!asoc->peer.reconf_capable ||
449 	    !(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ)) {
450 		retval = -ENOPROTOOPT;
451 		goto out;
452 	}
453 
454 	if (asoc->strreset_outstanding) {
455 		retval = -EINPROGRESS;
456 		goto out;
457 	}
458 
459 	out = params->sas_outstrms;
460 	in  = params->sas_instrms;
461 	outcnt = stream->outcnt + out;
462 	incnt = stream->incnt + in;
463 	if (outcnt > SCTP_MAX_STREAM || incnt > SCTP_MAX_STREAM ||
464 	    (!out && !in)) {
465 		retval = -EINVAL;
466 		goto out;
467 	}
468 
469 	if (out) {
470 		retval = sctp_stream_alloc_out(stream, outcnt, GFP_KERNEL);
471 		if (retval)
472 			goto out;
473 	}
474 
475 	chunk = sctp_make_strreset_addstrm(asoc, out, in);
476 	if (!chunk) {
477 		retval = -ENOMEM;
478 		goto out;
479 	}
480 
481 	asoc->strreset_chunk = chunk;
482 	sctp_chunk_hold(asoc->strreset_chunk);
483 
484 	retval = sctp_send_reconf(asoc, chunk);
485 	if (retval) {
486 		sctp_chunk_put(asoc->strreset_chunk);
487 		asoc->strreset_chunk = NULL;
488 		goto out;
489 	}
490 
491 	stream->incnt = incnt;
492 	stream->outcnt = outcnt;
493 
494 	asoc->strreset_outstanding = !!out + !!in;
495 
496 out:
497 	return retval;
498 }
499 
500 static struct sctp_paramhdr *sctp_chunk_lookup_strreset_param(
501 			struct sctp_association *asoc, __be32 resp_seq,
502 			__be16 type)
503 {
504 	struct sctp_chunk *chunk = asoc->strreset_chunk;
505 	struct sctp_reconf_chunk *hdr;
506 	union sctp_params param;
507 
508 	if (!chunk)
509 		return NULL;
510 
511 	hdr = (struct sctp_reconf_chunk *)chunk->chunk_hdr;
512 	sctp_walk_params(param, hdr, params) {
513 		/* sctp_strreset_tsnreq is actually the basic structure
514 		 * of all stream reconf params, so it's safe to use it
515 		 * to access request_seq.
516 		 */
517 		struct sctp_strreset_tsnreq *req = param.v;
518 
519 		if ((!resp_seq || req->request_seq == resp_seq) &&
520 		    (!type || type == req->param_hdr.type))
521 			return param.v;
522 	}
523 
524 	return NULL;
525 }
526 
527 static void sctp_update_strreset_result(struct sctp_association *asoc,
528 					__u32 result)
529 {
530 	asoc->strreset_result[1] = asoc->strreset_result[0];
531 	asoc->strreset_result[0] = result;
532 }
533 
534 struct sctp_chunk *sctp_process_strreset_outreq(
535 				struct sctp_association *asoc,
536 				union sctp_params param,
537 				struct sctp_ulpevent **evp)
538 {
539 	struct sctp_strreset_outreq *outreq = param.v;
540 	struct sctp_stream *stream = &asoc->stream;
541 	__u32 result = SCTP_STRRESET_DENIED;
542 	__u16 i, nums, flags = 0;
543 	__be16 *str_p = NULL;
544 	__u32 request_seq;
545 
546 	request_seq = ntohl(outreq->request_seq);
547 
548 	if (ntohl(outreq->send_reset_at_tsn) >
549 	    sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map)) {
550 		result = SCTP_STRRESET_IN_PROGRESS;
551 		goto err;
552 	}
553 
554 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
555 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
556 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
557 		goto err;
558 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
559 		i = asoc->strreset_inseq - request_seq - 1;
560 		result = asoc->strreset_result[i];
561 		goto err;
562 	}
563 	asoc->strreset_inseq++;
564 
565 	/* Check strreset_enable after inseq inc, as sender cannot tell
566 	 * the peer doesn't enable strreset after receiving response with
567 	 * result denied, as well as to keep consistent with bsd.
568 	 */
569 	if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
570 		goto out;
571 
572 	if (asoc->strreset_chunk) {
573 		if (!sctp_chunk_lookup_strreset_param(
574 				asoc, outreq->response_seq,
575 				SCTP_PARAM_RESET_IN_REQUEST)) {
576 			/* same process with outstanding isn't 0 */
577 			result = SCTP_STRRESET_ERR_IN_PROGRESS;
578 			goto out;
579 		}
580 
581 		asoc->strreset_outstanding--;
582 		asoc->strreset_outseq++;
583 
584 		if (!asoc->strreset_outstanding) {
585 			struct sctp_transport *t;
586 
587 			t = asoc->strreset_chunk->transport;
588 			if (del_timer(&t->reconf_timer))
589 				sctp_transport_put(t);
590 
591 			sctp_chunk_put(asoc->strreset_chunk);
592 			asoc->strreset_chunk = NULL;
593 		}
594 
595 		flags = SCTP_STREAM_RESET_INCOMING_SSN;
596 	}
597 
598 	nums = (ntohs(param.p->length) - sizeof(*outreq)) / sizeof(__u16);
599 	if (nums) {
600 		str_p = outreq->list_of_streams;
601 		for (i = 0; i < nums; i++) {
602 			if (ntohs(str_p[i]) >= stream->incnt) {
603 				result = SCTP_STRRESET_ERR_WRONG_SSN;
604 				goto out;
605 			}
606 		}
607 
608 		for (i = 0; i < nums; i++)
609 			stream->in[ntohs(str_p[i])].ssn = 0;
610 	} else {
611 		for (i = 0; i < stream->incnt; i++)
612 			stream->in[i].ssn = 0;
613 	}
614 
615 	result = SCTP_STRRESET_PERFORMED;
616 
617 	*evp = sctp_ulpevent_make_stream_reset_event(asoc,
618 		flags | SCTP_STREAM_RESET_OUTGOING_SSN, nums, str_p,
619 		GFP_ATOMIC);
620 
621 out:
622 	sctp_update_strreset_result(asoc, result);
623 err:
624 	return sctp_make_strreset_resp(asoc, result, request_seq);
625 }
626 
627 struct sctp_chunk *sctp_process_strreset_inreq(
628 				struct sctp_association *asoc,
629 				union sctp_params param,
630 				struct sctp_ulpevent **evp)
631 {
632 	struct sctp_strreset_inreq *inreq = param.v;
633 	struct sctp_stream *stream = &asoc->stream;
634 	__u32 result = SCTP_STRRESET_DENIED;
635 	struct sctp_chunk *chunk = NULL;
636 	__u32 request_seq;
637 	__u16 i, nums;
638 	__be16 *str_p;
639 
640 	request_seq = ntohl(inreq->request_seq);
641 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
642 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
643 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
644 		goto err;
645 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
646 		i = asoc->strreset_inseq - request_seq - 1;
647 		result = asoc->strreset_result[i];
648 		if (result == SCTP_STRRESET_PERFORMED)
649 			return NULL;
650 		goto err;
651 	}
652 	asoc->strreset_inseq++;
653 
654 	if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
655 		goto out;
656 
657 	if (asoc->strreset_outstanding) {
658 		result = SCTP_STRRESET_ERR_IN_PROGRESS;
659 		goto out;
660 	}
661 
662 	nums = (ntohs(param.p->length) - sizeof(*inreq)) / sizeof(__u16);
663 	str_p = inreq->list_of_streams;
664 	for (i = 0; i < nums; i++) {
665 		if (ntohs(str_p[i]) >= stream->outcnt) {
666 			result = SCTP_STRRESET_ERR_WRONG_SSN;
667 			goto out;
668 		}
669 	}
670 
671 	if (!sctp_stream_outq_is_empty(stream, nums, str_p)) {
672 		result = SCTP_STRRESET_IN_PROGRESS;
673 		asoc->strreset_inseq--;
674 		goto err;
675 	}
676 
677 	chunk = sctp_make_strreset_req(asoc, nums, str_p, 1, 0);
678 	if (!chunk)
679 		goto out;
680 
681 	if (nums)
682 		for (i = 0; i < nums; i++)
683 			stream->out[ntohs(str_p[i])].state =
684 					       SCTP_STREAM_CLOSED;
685 	else
686 		for (i = 0; i < stream->outcnt; i++)
687 			stream->out[i].state = SCTP_STREAM_CLOSED;
688 
689 	asoc->strreset_chunk = chunk;
690 	asoc->strreset_outstanding = 1;
691 	sctp_chunk_hold(asoc->strreset_chunk);
692 
693 	result = SCTP_STRRESET_PERFORMED;
694 
695 	*evp = sctp_ulpevent_make_stream_reset_event(asoc,
696 		SCTP_STREAM_RESET_INCOMING_SSN, nums, str_p, GFP_ATOMIC);
697 
698 out:
699 	sctp_update_strreset_result(asoc, result);
700 err:
701 	if (!chunk)
702 		chunk =  sctp_make_strreset_resp(asoc, result, request_seq);
703 
704 	return chunk;
705 }
706 
707 struct sctp_chunk *sctp_process_strreset_tsnreq(
708 				struct sctp_association *asoc,
709 				union sctp_params param,
710 				struct sctp_ulpevent **evp)
711 {
712 	__u32 init_tsn = 0, next_tsn = 0, max_tsn_seen;
713 	struct sctp_strreset_tsnreq *tsnreq = param.v;
714 	struct sctp_stream *stream = &asoc->stream;
715 	__u32 result = SCTP_STRRESET_DENIED;
716 	__u32 request_seq;
717 	__u16 i;
718 
719 	request_seq = ntohl(tsnreq->request_seq);
720 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
721 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
722 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
723 		goto err;
724 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
725 		i = asoc->strreset_inseq - request_seq - 1;
726 		result = asoc->strreset_result[i];
727 		if (result == SCTP_STRRESET_PERFORMED) {
728 			next_tsn = asoc->ctsn_ack_point + 1;
729 			init_tsn =
730 				sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + 1;
731 		}
732 		goto err;
733 	}
734 
735 	if (!sctp_outq_is_empty(&asoc->outqueue)) {
736 		result = SCTP_STRRESET_IN_PROGRESS;
737 		goto err;
738 	}
739 
740 	asoc->strreset_inseq++;
741 
742 	if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
743 		goto out;
744 
745 	if (asoc->strreset_outstanding) {
746 		result = SCTP_STRRESET_ERR_IN_PROGRESS;
747 		goto out;
748 	}
749 
750 	/* G4: The same processing as though a FWD-TSN chunk (as defined in
751 	 *     [RFC3758]) with all streams affected and a new cumulative TSN
752 	 *     ACK of the Receiver's Next TSN minus 1 were received MUST be
753 	 *     performed.
754 	 */
755 	max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
756 	sctp_ulpq_reasm_flushtsn(&asoc->ulpq, max_tsn_seen);
757 	sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
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].ssn = 0;
788 	for (i = 0; i < stream->incnt; i++)
789 		stream->in[i].ssn = 0;
790 
791 	result = SCTP_STRRESET_PERFORMED;
792 
793 	*evp = sctp_ulpevent_make_assoc_reset_event(asoc, 0, init_tsn,
794 						    next_tsn, GFP_ATOMIC);
795 
796 out:
797 	sctp_update_strreset_result(asoc, result);
798 err:
799 	return sctp_make_strreset_tsnresp(asoc, result, request_seq,
800 					  next_tsn, init_tsn);
801 }
802 
803 struct sctp_chunk *sctp_process_strreset_addstrm_out(
804 				struct sctp_association *asoc,
805 				union sctp_params param,
806 				struct sctp_ulpevent **evp)
807 {
808 	struct sctp_strreset_addstrm *addstrm = param.v;
809 	struct sctp_stream *stream = &asoc->stream;
810 	__u32 result = SCTP_STRRESET_DENIED;
811 	__u32 request_seq, incnt;
812 	__u16 in, i;
813 
814 	request_seq = ntohl(addstrm->request_seq);
815 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
816 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
817 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
818 		goto err;
819 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
820 		i = asoc->strreset_inseq - request_seq - 1;
821 		result = asoc->strreset_result[i];
822 		goto err;
823 	}
824 	asoc->strreset_inseq++;
825 
826 	if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
827 		goto out;
828 
829 	if (asoc->strreset_chunk) {
830 		if (!sctp_chunk_lookup_strreset_param(
831 			asoc, 0, SCTP_PARAM_RESET_ADD_IN_STREAMS)) {
832 			/* same process with outstanding isn't 0 */
833 			result = SCTP_STRRESET_ERR_IN_PROGRESS;
834 			goto out;
835 		}
836 
837 		asoc->strreset_outstanding--;
838 		asoc->strreset_outseq++;
839 
840 		if (!asoc->strreset_outstanding) {
841 			struct sctp_transport *t;
842 
843 			t = asoc->strreset_chunk->transport;
844 			if (del_timer(&t->reconf_timer))
845 				sctp_transport_put(t);
846 
847 			sctp_chunk_put(asoc->strreset_chunk);
848 			asoc->strreset_chunk = NULL;
849 		}
850 	}
851 
852 	in = ntohs(addstrm->number_of_streams);
853 	incnt = stream->incnt + in;
854 	if (!in || incnt > SCTP_MAX_STREAM)
855 		goto out;
856 
857 	if (sctp_stream_alloc_in(stream, incnt, GFP_ATOMIC))
858 		goto out;
859 
860 	stream->incnt = incnt;
861 
862 	result = SCTP_STRRESET_PERFORMED;
863 
864 	*evp = sctp_ulpevent_make_stream_change_event(asoc,
865 		0, ntohs(addstrm->number_of_streams), 0, GFP_ATOMIC);
866 
867 out:
868 	sctp_update_strreset_result(asoc, result);
869 err:
870 	return sctp_make_strreset_resp(asoc, result, request_seq);
871 }
872 
873 struct sctp_chunk *sctp_process_strreset_addstrm_in(
874 				struct sctp_association *asoc,
875 				union sctp_params param,
876 				struct sctp_ulpevent **evp)
877 {
878 	struct sctp_strreset_addstrm *addstrm = param.v;
879 	struct sctp_stream *stream = &asoc->stream;
880 	__u32 result = SCTP_STRRESET_DENIED;
881 	struct sctp_chunk *chunk = NULL;
882 	__u32 request_seq, outcnt;
883 	__u16 out, i;
884 	int ret;
885 
886 	request_seq = ntohl(addstrm->request_seq);
887 	if (TSN_lt(asoc->strreset_inseq, request_seq) ||
888 	    TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
889 		result = SCTP_STRRESET_ERR_BAD_SEQNO;
890 		goto err;
891 	} else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
892 		i = asoc->strreset_inseq - request_seq - 1;
893 		result = asoc->strreset_result[i];
894 		if (result == SCTP_STRRESET_PERFORMED)
895 			return NULL;
896 		goto err;
897 	}
898 	asoc->strreset_inseq++;
899 
900 	if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
901 		goto out;
902 
903 	if (asoc->strreset_outstanding) {
904 		result = SCTP_STRRESET_ERR_IN_PROGRESS;
905 		goto out;
906 	}
907 
908 	out = ntohs(addstrm->number_of_streams);
909 	outcnt = stream->outcnt + out;
910 	if (!out || outcnt > SCTP_MAX_STREAM)
911 		goto out;
912 
913 	ret = sctp_stream_alloc_out(stream, outcnt, GFP_ATOMIC);
914 	if (ret)
915 		goto out;
916 
917 	chunk = sctp_make_strreset_addstrm(asoc, out, 0);
918 	if (!chunk)
919 		goto out;
920 
921 	asoc->strreset_chunk = chunk;
922 	asoc->strreset_outstanding = 1;
923 	sctp_chunk_hold(asoc->strreset_chunk);
924 
925 	stream->outcnt = outcnt;
926 
927 	result = SCTP_STRRESET_PERFORMED;
928 
929 	*evp = sctp_ulpevent_make_stream_change_event(asoc,
930 		0, 0, ntohs(addstrm->number_of_streams), GFP_ATOMIC);
931 
932 out:
933 	sctp_update_strreset_result(asoc, result);
934 err:
935 	if (!chunk)
936 		chunk = sctp_make_strreset_resp(asoc, result, request_seq);
937 
938 	return chunk;
939 }
940 
941 struct sctp_chunk *sctp_process_strreset_resp(
942 				struct sctp_association *asoc,
943 				union sctp_params param,
944 				struct sctp_ulpevent **evp)
945 {
946 	struct sctp_stream *stream = &asoc->stream;
947 	struct sctp_strreset_resp *resp = param.v;
948 	struct sctp_transport *t;
949 	__u16 i, nums, flags = 0;
950 	struct sctp_paramhdr *req;
951 	__u32 result;
952 
953 	req = sctp_chunk_lookup_strreset_param(asoc, resp->response_seq, 0);
954 	if (!req)
955 		return NULL;
956 
957 	result = ntohl(resp->result);
958 	if (result != SCTP_STRRESET_PERFORMED) {
959 		/* if in progress, do nothing but retransmit */
960 		if (result == SCTP_STRRESET_IN_PROGRESS)
961 			return NULL;
962 		else if (result == SCTP_STRRESET_DENIED)
963 			flags = SCTP_STREAM_RESET_DENIED;
964 		else
965 			flags = SCTP_STREAM_RESET_FAILED;
966 	}
967 
968 	if (req->type == SCTP_PARAM_RESET_OUT_REQUEST) {
969 		struct sctp_strreset_outreq *outreq;
970 		__be16 *str_p;
971 
972 		outreq = (struct sctp_strreset_outreq *)req;
973 		str_p = outreq->list_of_streams;
974 		nums = (ntohs(outreq->param_hdr.length) - sizeof(*outreq)) /
975 		       sizeof(__u16);
976 
977 		if (result == SCTP_STRRESET_PERFORMED) {
978 			if (nums) {
979 				for (i = 0; i < nums; i++)
980 					stream->out[ntohs(str_p[i])].ssn = 0;
981 			} else {
982 				for (i = 0; i < stream->outcnt; i++)
983 					stream->out[i].ssn = 0;
984 			}
985 
986 			flags = SCTP_STREAM_RESET_OUTGOING_SSN;
987 		}
988 
989 		for (i = 0; i < stream->outcnt; i++)
990 			stream->out[i].state = SCTP_STREAM_OPEN;
991 
992 		*evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
993 			nums, str_p, GFP_ATOMIC);
994 	} else if (req->type == SCTP_PARAM_RESET_IN_REQUEST) {
995 		struct sctp_strreset_inreq *inreq;
996 		__be16 *str_p;
997 
998 		/* if the result is performed, it's impossible for inreq */
999 		if (result == SCTP_STRRESET_PERFORMED)
1000 			return NULL;
1001 
1002 		inreq = (struct sctp_strreset_inreq *)req;
1003 		str_p = inreq->list_of_streams;
1004 		nums = (ntohs(inreq->param_hdr.length) - sizeof(*inreq)) /
1005 		       sizeof(__u16);
1006 
1007 		*evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
1008 			nums, str_p, GFP_ATOMIC);
1009 	} else if (req->type == SCTP_PARAM_RESET_TSN_REQUEST) {
1010 		struct sctp_strreset_resptsn *resptsn;
1011 		__u32 stsn, rtsn;
1012 
1013 		/* check for resptsn, as sctp_verify_reconf didn't do it*/
1014 		if (ntohs(param.p->length) != sizeof(*resptsn))
1015 			return NULL;
1016 
1017 		resptsn = (struct sctp_strreset_resptsn *)resp;
1018 		stsn = ntohl(resptsn->senders_next_tsn);
1019 		rtsn = ntohl(resptsn->receivers_next_tsn);
1020 
1021 		if (result == SCTP_STRRESET_PERFORMED) {
1022 			__u32 mtsn = sctp_tsnmap_get_max_tsn_seen(
1023 						&asoc->peer.tsn_map);
1024 			LIST_HEAD(temp);
1025 
1026 			sctp_ulpq_reasm_flushtsn(&asoc->ulpq, mtsn);
1027 			sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
1028 
1029 			sctp_tsnmap_init(&asoc->peer.tsn_map,
1030 					 SCTP_TSN_MAP_INITIAL,
1031 					 stsn, GFP_ATOMIC);
1032 
1033 			/* Clean up sacked and abandoned queues only. As the
1034 			 * out_chunk_list may not be empty, splice it to temp,
1035 			 * then get it back after sctp_outq_free is done.
1036 			 */
1037 			list_splice_init(&asoc->outqueue.out_chunk_list, &temp);
1038 			sctp_outq_free(&asoc->outqueue);
1039 			list_splice_init(&temp, &asoc->outqueue.out_chunk_list);
1040 
1041 			asoc->next_tsn = rtsn;
1042 			asoc->ctsn_ack_point = asoc->next_tsn - 1;
1043 			asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
1044 
1045 			for (i = 0; i < stream->outcnt; i++)
1046 				stream->out[i].ssn = 0;
1047 			for (i = 0; i < stream->incnt; i++)
1048 				stream->in[i].ssn = 0;
1049 		}
1050 
1051 		for (i = 0; i < stream->outcnt; i++)
1052 			stream->out[i].state = SCTP_STREAM_OPEN;
1053 
1054 		*evp = sctp_ulpevent_make_assoc_reset_event(asoc, flags,
1055 			stsn, rtsn, GFP_ATOMIC);
1056 	} else if (req->type == SCTP_PARAM_RESET_ADD_OUT_STREAMS) {
1057 		struct sctp_strreset_addstrm *addstrm;
1058 		__u16 number;
1059 
1060 		addstrm = (struct sctp_strreset_addstrm *)req;
1061 		nums = ntohs(addstrm->number_of_streams);
1062 		number = stream->outcnt - nums;
1063 
1064 		if (result == SCTP_STRRESET_PERFORMED)
1065 			for (i = number; i < stream->outcnt; i++)
1066 				stream->out[i].state = SCTP_STREAM_OPEN;
1067 		else
1068 			stream->outcnt = number;
1069 
1070 		*evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1071 			0, nums, GFP_ATOMIC);
1072 	} else if (req->type == SCTP_PARAM_RESET_ADD_IN_STREAMS) {
1073 		struct sctp_strreset_addstrm *addstrm;
1074 
1075 		/* if the result is performed, it's impossible for addstrm in
1076 		 * request.
1077 		 */
1078 		if (result == SCTP_STRRESET_PERFORMED)
1079 			return NULL;
1080 
1081 		addstrm = (struct sctp_strreset_addstrm *)req;
1082 		nums = ntohs(addstrm->number_of_streams);
1083 
1084 		*evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1085 			nums, 0, GFP_ATOMIC);
1086 	}
1087 
1088 	asoc->strreset_outstanding--;
1089 	asoc->strreset_outseq++;
1090 
1091 	/* remove everything for this reconf request */
1092 	if (!asoc->strreset_outstanding) {
1093 		t = asoc->strreset_chunk->transport;
1094 		if (del_timer(&t->reconf_timer))
1095 			sctp_transport_put(t);
1096 
1097 		sctp_chunk_put(asoc->strreset_chunk);
1098 		asoc->strreset_chunk = NULL;
1099 	}
1100 
1101 	return NULL;
1102 }
1103