Merge tag 'arc-5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
[sfrench/cifs-2.6.git] / net / sctp / stream.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* SCTP kernel implementation
3  * (C) Copyright IBM Corp. 2001, 2004
4  * Copyright (c) 1999-2000 Cisco, Inc.
5  * Copyright (c) 1999-2001 Motorola, Inc.
6  * Copyright (c) 2001 Intel Corp.
7  *
8  * This file is part of the SCTP kernel implementation
9  *
10  * This file contains sctp stream maniuplation primitives and helpers.
11  *
12  * Please send any bug reports or fixes you make to the
13  * email address(es):
14  *    lksctp developers <linux-sctp@vger.kernel.org>
15  *
16  * Written or modified by:
17  *    Xin Long <lucien.xin@gmail.com>
18  */
19
20 #include <linux/list.h>
21 #include <net/sctp/sctp.h>
22 #include <net/sctp/sm.h>
23 #include <net/sctp/stream_sched.h>
24
25 /* Migrates chunks from stream queues to new stream queues if needed,
26  * but not across associations. Also, removes those chunks to streams
27  * higher than the new max.
28  */
29 static void sctp_stream_outq_migrate(struct sctp_stream *stream,
30                                      struct sctp_stream *new, __u16 outcnt)
31 {
32         struct sctp_association *asoc;
33         struct sctp_chunk *ch, *temp;
34         struct sctp_outq *outq;
35         int i;
36
37         asoc = container_of(stream, struct sctp_association, stream);
38         outq = &asoc->outqueue;
39
40         list_for_each_entry_safe(ch, temp, &outq->out_chunk_list, list) {
41                 __u16 sid = sctp_chunk_stream_no(ch);
42
43                 if (sid < outcnt)
44                         continue;
45
46                 sctp_sched_dequeue_common(outq, ch);
47                 /* No need to call dequeue_done here because
48                  * the chunks are not scheduled by now.
49                  */
50
51                 /* Mark as failed send. */
52                 sctp_chunk_fail(ch, (__force __u32)SCTP_ERROR_INV_STRM);
53                 if (asoc->peer.prsctp_capable &&
54                     SCTP_PR_PRIO_ENABLED(ch->sinfo.sinfo_flags))
55                         asoc->sent_cnt_removable--;
56
57                 sctp_chunk_free(ch);
58         }
59
60         if (new) {
61                 /* Here we actually move the old ext stuff into the new
62                  * buffer, because we want to keep it. Then
63                  * sctp_stream_update will swap ->out pointers.
64                  */
65                 for (i = 0; i < outcnt; i++) {
66                         kfree(SCTP_SO(new, i)->ext);
67                         SCTP_SO(new, i)->ext = SCTP_SO(stream, i)->ext;
68                         SCTP_SO(stream, i)->ext = NULL;
69                 }
70         }
71
72         for (i = outcnt; i < stream->outcnt; i++) {
73                 kfree(SCTP_SO(stream, i)->ext);
74                 SCTP_SO(stream, i)->ext = NULL;
75         }
76 }
77
78 static int sctp_stream_alloc_out(struct sctp_stream *stream, __u16 outcnt,
79                                  gfp_t gfp)
80 {
81         int ret;
82
83         if (outcnt <= stream->outcnt)
84                 return 0;
85
86         ret = genradix_prealloc(&stream->out, outcnt, gfp);
87         if (ret)
88                 return ret;
89
90         stream->outcnt = outcnt;
91         return 0;
92 }
93
94 static int sctp_stream_alloc_in(struct sctp_stream *stream, __u16 incnt,
95                                 gfp_t gfp)
96 {
97         int ret;
98
99         if (incnt <= stream->incnt)
100                 return 0;
101
102         ret = genradix_prealloc(&stream->in, incnt, gfp);
103         if (ret)
104                 return ret;
105
106         stream->incnt = incnt;
107         return 0;
108 }
109
110 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt,
111                      gfp_t gfp)
112 {
113         struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
114         int i, ret = 0;
115
116         gfp |= __GFP_NOWARN;
117
118         /* Initial stream->out size may be very big, so free it and alloc
119          * a new one with new outcnt to save memory if needed.
120          */
121         if (outcnt == stream->outcnt)
122                 goto in;
123
124         /* Filter out chunks queued on streams that won't exist anymore */
125         sched->unsched_all(stream);
126         sctp_stream_outq_migrate(stream, NULL, outcnt);
127         sched->sched_all(stream);
128
129         ret = sctp_stream_alloc_out(stream, outcnt, gfp);
130         if (ret)
131                 goto out;
132
133         for (i = 0; i < stream->outcnt; i++)
134                 SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
135
136 in:
137         sctp_stream_interleave_init(stream);
138         if (!incnt)
139                 goto out;
140
141         ret = sctp_stream_alloc_in(stream, incnt, gfp);
142         if (ret) {
143                 sched->free(stream);
144                 genradix_free(&stream->out);
145                 stream->outcnt = 0;
146                 goto out;
147         }
148
149 out:
150         return ret;
151 }
152
153 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid)
154 {
155         struct sctp_stream_out_ext *soute;
156
157         soute = kzalloc(sizeof(*soute), GFP_KERNEL);
158         if (!soute)
159                 return -ENOMEM;
160         SCTP_SO(stream, sid)->ext = soute;
161
162         return sctp_sched_init_sid(stream, sid, GFP_KERNEL);
163 }
164
165 void sctp_stream_free(struct sctp_stream *stream)
166 {
167         struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
168         int i;
169
170         sched->free(stream);
171         for (i = 0; i < stream->outcnt; i++)
172                 kfree(SCTP_SO(stream, i)->ext);
173         genradix_free(&stream->out);
174         genradix_free(&stream->in);
175 }
176
177 void sctp_stream_clear(struct sctp_stream *stream)
178 {
179         int i;
180
181         for (i = 0; i < stream->outcnt; i++) {
182                 SCTP_SO(stream, i)->mid = 0;
183                 SCTP_SO(stream, i)->mid_uo = 0;
184         }
185
186         for (i = 0; i < stream->incnt; i++)
187                 SCTP_SI(stream, i)->mid = 0;
188 }
189
190 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new)
191 {
192         struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
193
194         sched->unsched_all(stream);
195         sctp_stream_outq_migrate(stream, new, new->outcnt);
196         sctp_stream_free(stream);
197
198         stream->out = new->out;
199         stream->in  = new->in;
200         stream->outcnt = new->outcnt;
201         stream->incnt  = new->incnt;
202
203         sched->sched_all(stream);
204
205         new->out.tree.root = NULL;
206         new->in.tree.root  = NULL;
207         new->outcnt = 0;
208         new->incnt  = 0;
209 }
210
211 static int sctp_send_reconf(struct sctp_association *asoc,
212                             struct sctp_chunk *chunk)
213 {
214         struct net *net = sock_net(asoc->base.sk);
215         int retval = 0;
216
217         retval = sctp_primitive_RECONF(net, asoc, chunk);
218         if (retval)
219                 sctp_chunk_free(chunk);
220
221         return retval;
222 }
223
224 static bool sctp_stream_outq_is_empty(struct sctp_stream *stream,
225                                       __u16 str_nums, __be16 *str_list)
226 {
227         struct sctp_association *asoc;
228         __u16 i;
229
230         asoc = container_of(stream, struct sctp_association, stream);
231         if (!asoc->outqueue.out_qlen)
232                 return true;
233
234         if (!str_nums)
235                 return false;
236
237         for (i = 0; i < str_nums; i++) {
238                 __u16 sid = ntohs(str_list[i]);
239
240                 if (SCTP_SO(stream, sid)->ext &&
241                     !list_empty(&SCTP_SO(stream, sid)->ext->outq))
242                         return false;
243         }
244
245         return true;
246 }
247
248 int sctp_send_reset_streams(struct sctp_association *asoc,
249                             struct sctp_reset_streams *params)
250 {
251         struct sctp_stream *stream = &asoc->stream;
252         __u16 i, str_nums, *str_list;
253         struct sctp_chunk *chunk;
254         int retval = -EINVAL;
255         __be16 *nstr_list;
256         bool out, in;
257
258         if (!asoc->peer.reconf_capable ||
259             !(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ)) {
260                 retval = -ENOPROTOOPT;
261                 goto out;
262         }
263
264         if (asoc->strreset_outstanding) {
265                 retval = -EINPROGRESS;
266                 goto out;
267         }
268
269         out = params->srs_flags & SCTP_STREAM_RESET_OUTGOING;
270         in  = params->srs_flags & SCTP_STREAM_RESET_INCOMING;
271         if (!out && !in)
272                 goto out;
273
274         str_nums = params->srs_number_streams;
275         str_list = params->srs_stream_list;
276         if (str_nums) {
277                 int param_len = 0;
278
279                 if (out) {
280                         for (i = 0; i < str_nums; i++)
281                                 if (str_list[i] >= stream->outcnt)
282                                         goto out;
283
284                         param_len = str_nums * sizeof(__u16) +
285                                     sizeof(struct sctp_strreset_outreq);
286                 }
287
288                 if (in) {
289                         for (i = 0; i < str_nums; i++)
290                                 if (str_list[i] >= stream->incnt)
291                                         goto out;
292
293                         param_len += str_nums * sizeof(__u16) +
294                                      sizeof(struct sctp_strreset_inreq);
295                 }
296
297                 if (param_len > SCTP_MAX_CHUNK_LEN -
298                                 sizeof(struct sctp_reconf_chunk))
299                         goto out;
300         }
301
302         nstr_list = kcalloc(str_nums, sizeof(__be16), GFP_KERNEL);
303         if (!nstr_list) {
304                 retval = -ENOMEM;
305                 goto out;
306         }
307
308         for (i = 0; i < str_nums; i++)
309                 nstr_list[i] = htons(str_list[i]);
310
311         if (out && !sctp_stream_outq_is_empty(stream, str_nums, nstr_list)) {
312                 retval = -EAGAIN;
313                 goto out;
314         }
315
316         chunk = sctp_make_strreset_req(asoc, str_nums, nstr_list, out, in);
317
318         kfree(nstr_list);
319
320         if (!chunk) {
321                 retval = -ENOMEM;
322                 goto out;
323         }
324
325         if (out) {
326                 if (str_nums)
327                         for (i = 0; i < str_nums; i++)
328                                 SCTP_SO(stream, str_list[i])->state =
329                                                        SCTP_STREAM_CLOSED;
330                 else
331                         for (i = 0; i < stream->outcnt; i++)
332                                 SCTP_SO(stream, i)->state = SCTP_STREAM_CLOSED;
333         }
334
335         asoc->strreset_chunk = chunk;
336         sctp_chunk_hold(asoc->strreset_chunk);
337
338         retval = sctp_send_reconf(asoc, chunk);
339         if (retval) {
340                 sctp_chunk_put(asoc->strreset_chunk);
341                 asoc->strreset_chunk = NULL;
342                 if (!out)
343                         goto out;
344
345                 if (str_nums)
346                         for (i = 0; i < str_nums; i++)
347                                 SCTP_SO(stream, str_list[i])->state =
348                                                        SCTP_STREAM_OPEN;
349                 else
350                         for (i = 0; i < stream->outcnt; i++)
351                                 SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
352
353                 goto out;
354         }
355
356         asoc->strreset_outstanding = out + in;
357
358 out:
359         return retval;
360 }
361
362 int sctp_send_reset_assoc(struct sctp_association *asoc)
363 {
364         struct sctp_stream *stream = &asoc->stream;
365         struct sctp_chunk *chunk = NULL;
366         int retval;
367         __u16 i;
368
369         if (!asoc->peer.reconf_capable ||
370             !(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
371                 return -ENOPROTOOPT;
372
373         if (asoc->strreset_outstanding)
374                 return -EINPROGRESS;
375
376         if (!sctp_outq_is_empty(&asoc->outqueue))
377                 return -EAGAIN;
378
379         chunk = sctp_make_strreset_tsnreq(asoc);
380         if (!chunk)
381                 return -ENOMEM;
382
383         /* Block further xmit of data until this request is completed */
384         for (i = 0; i < stream->outcnt; i++)
385                 SCTP_SO(stream, i)->state = SCTP_STREAM_CLOSED;
386
387         asoc->strreset_chunk = chunk;
388         sctp_chunk_hold(asoc->strreset_chunk);
389
390         retval = sctp_send_reconf(asoc, chunk);
391         if (retval) {
392                 sctp_chunk_put(asoc->strreset_chunk);
393                 asoc->strreset_chunk = NULL;
394
395                 for (i = 0; i < stream->outcnt; i++)
396                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
397
398                 return retval;
399         }
400
401         asoc->strreset_outstanding = 1;
402
403         return 0;
404 }
405
406 int sctp_send_add_streams(struct sctp_association *asoc,
407                           struct sctp_add_streams *params)
408 {
409         struct sctp_stream *stream = &asoc->stream;
410         struct sctp_chunk *chunk = NULL;
411         int retval;
412         __u32 outcnt, incnt;
413         __u16 out, in;
414
415         if (!asoc->peer.reconf_capable ||
416             !(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ)) {
417                 retval = -ENOPROTOOPT;
418                 goto out;
419         }
420
421         if (asoc->strreset_outstanding) {
422                 retval = -EINPROGRESS;
423                 goto out;
424         }
425
426         out = params->sas_outstrms;
427         in  = params->sas_instrms;
428         outcnt = stream->outcnt + out;
429         incnt = stream->incnt + in;
430         if (outcnt > SCTP_MAX_STREAM || incnt > SCTP_MAX_STREAM ||
431             (!out && !in)) {
432                 retval = -EINVAL;
433                 goto out;
434         }
435
436         if (out) {
437                 retval = sctp_stream_alloc_out(stream, outcnt, GFP_KERNEL);
438                 if (retval)
439                         goto out;
440         }
441
442         chunk = sctp_make_strreset_addstrm(asoc, out, in);
443         if (!chunk) {
444                 retval = -ENOMEM;
445                 goto out;
446         }
447
448         asoc->strreset_chunk = chunk;
449         sctp_chunk_hold(asoc->strreset_chunk);
450
451         retval = sctp_send_reconf(asoc, chunk);
452         if (retval) {
453                 sctp_chunk_put(asoc->strreset_chunk);
454                 asoc->strreset_chunk = NULL;
455                 goto out;
456         }
457
458         asoc->strreset_outstanding = !!out + !!in;
459
460 out:
461         return retval;
462 }
463
464 static struct sctp_paramhdr *sctp_chunk_lookup_strreset_param(
465                         struct sctp_association *asoc, __be32 resp_seq,
466                         __be16 type)
467 {
468         struct sctp_chunk *chunk = asoc->strreset_chunk;
469         struct sctp_reconf_chunk *hdr;
470         union sctp_params param;
471
472         if (!chunk)
473                 return NULL;
474
475         hdr = (struct sctp_reconf_chunk *)chunk->chunk_hdr;
476         sctp_walk_params(param, hdr, params) {
477                 /* sctp_strreset_tsnreq is actually the basic structure
478                  * of all stream reconf params, so it's safe to use it
479                  * to access request_seq.
480                  */
481                 struct sctp_strreset_tsnreq *req = param.v;
482
483                 if ((!resp_seq || req->request_seq == resp_seq) &&
484                     (!type || type == req->param_hdr.type))
485                         return param.v;
486         }
487
488         return NULL;
489 }
490
491 static void sctp_update_strreset_result(struct sctp_association *asoc,
492                                         __u32 result)
493 {
494         asoc->strreset_result[1] = asoc->strreset_result[0];
495         asoc->strreset_result[0] = result;
496 }
497
498 struct sctp_chunk *sctp_process_strreset_outreq(
499                                 struct sctp_association *asoc,
500                                 union sctp_params param,
501                                 struct sctp_ulpevent **evp)
502 {
503         struct sctp_strreset_outreq *outreq = param.v;
504         struct sctp_stream *stream = &asoc->stream;
505         __u32 result = SCTP_STRRESET_DENIED;
506         __be16 *str_p = NULL;
507         __u32 request_seq;
508         __u16 i, nums;
509
510         request_seq = ntohl(outreq->request_seq);
511
512         if (ntohl(outreq->send_reset_at_tsn) >
513             sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map)) {
514                 result = SCTP_STRRESET_IN_PROGRESS;
515                 goto err;
516         }
517
518         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
519             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
520                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
521                 goto err;
522         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
523                 i = asoc->strreset_inseq - request_seq - 1;
524                 result = asoc->strreset_result[i];
525                 goto err;
526         }
527         asoc->strreset_inseq++;
528
529         /* Check strreset_enable after inseq inc, as sender cannot tell
530          * the peer doesn't enable strreset after receiving response with
531          * result denied, as well as to keep consistent with bsd.
532          */
533         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
534                 goto out;
535
536         nums = (ntohs(param.p->length) - sizeof(*outreq)) / sizeof(__u16);
537         str_p = outreq->list_of_streams;
538         for (i = 0; i < nums; i++) {
539                 if (ntohs(str_p[i]) >= stream->incnt) {
540                         result = SCTP_STRRESET_ERR_WRONG_SSN;
541                         goto out;
542                 }
543         }
544
545         if (asoc->strreset_chunk) {
546                 if (!sctp_chunk_lookup_strreset_param(
547                                 asoc, outreq->response_seq,
548                                 SCTP_PARAM_RESET_IN_REQUEST)) {
549                         /* same process with outstanding isn't 0 */
550                         result = SCTP_STRRESET_ERR_IN_PROGRESS;
551                         goto out;
552                 }
553
554                 asoc->strreset_outstanding--;
555                 asoc->strreset_outseq++;
556
557                 if (!asoc->strreset_outstanding) {
558                         struct sctp_transport *t;
559
560                         t = asoc->strreset_chunk->transport;
561                         if (del_timer(&t->reconf_timer))
562                                 sctp_transport_put(t);
563
564                         sctp_chunk_put(asoc->strreset_chunk);
565                         asoc->strreset_chunk = NULL;
566                 }
567         }
568
569         if (nums)
570                 for (i = 0; i < nums; i++)
571                         SCTP_SI(stream, ntohs(str_p[i]))->mid = 0;
572         else
573                 for (i = 0; i < stream->incnt; i++)
574                         SCTP_SI(stream, i)->mid = 0;
575
576         result = SCTP_STRRESET_PERFORMED;
577
578         *evp = sctp_ulpevent_make_stream_reset_event(asoc,
579                 SCTP_STREAM_RESET_INCOMING_SSN, nums, str_p, GFP_ATOMIC);
580
581 out:
582         sctp_update_strreset_result(asoc, result);
583 err:
584         return sctp_make_strreset_resp(asoc, result, request_seq);
585 }
586
587 struct sctp_chunk *sctp_process_strreset_inreq(
588                                 struct sctp_association *asoc,
589                                 union sctp_params param,
590                                 struct sctp_ulpevent **evp)
591 {
592         struct sctp_strreset_inreq *inreq = param.v;
593         struct sctp_stream *stream = &asoc->stream;
594         __u32 result = SCTP_STRRESET_DENIED;
595         struct sctp_chunk *chunk = NULL;
596         __u32 request_seq;
597         __u16 i, nums;
598         __be16 *str_p;
599
600         request_seq = ntohl(inreq->request_seq);
601         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
602             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
603                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
604                 goto err;
605         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
606                 i = asoc->strreset_inseq - request_seq - 1;
607                 result = asoc->strreset_result[i];
608                 if (result == SCTP_STRRESET_PERFORMED)
609                         return NULL;
610                 goto err;
611         }
612         asoc->strreset_inseq++;
613
614         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
615                 goto out;
616
617         if (asoc->strreset_outstanding) {
618                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
619                 goto out;
620         }
621
622         nums = (ntohs(param.p->length) - sizeof(*inreq)) / sizeof(__u16);
623         str_p = inreq->list_of_streams;
624         for (i = 0; i < nums; i++) {
625                 if (ntohs(str_p[i]) >= stream->outcnt) {
626                         result = SCTP_STRRESET_ERR_WRONG_SSN;
627                         goto out;
628                 }
629         }
630
631         if (!sctp_stream_outq_is_empty(stream, nums, str_p)) {
632                 result = SCTP_STRRESET_IN_PROGRESS;
633                 asoc->strreset_inseq--;
634                 goto err;
635         }
636
637         chunk = sctp_make_strreset_req(asoc, nums, str_p, 1, 0);
638         if (!chunk)
639                 goto out;
640
641         if (nums)
642                 for (i = 0; i < nums; i++)
643                         SCTP_SO(stream, ntohs(str_p[i]))->state =
644                                                SCTP_STREAM_CLOSED;
645         else
646                 for (i = 0; i < stream->outcnt; i++)
647                         SCTP_SO(stream, i)->state = SCTP_STREAM_CLOSED;
648
649         asoc->strreset_chunk = chunk;
650         asoc->strreset_outstanding = 1;
651         sctp_chunk_hold(asoc->strreset_chunk);
652
653         result = SCTP_STRRESET_PERFORMED;
654
655 out:
656         sctp_update_strreset_result(asoc, result);
657 err:
658         if (!chunk)
659                 chunk =  sctp_make_strreset_resp(asoc, result, request_seq);
660
661         return chunk;
662 }
663
664 struct sctp_chunk *sctp_process_strreset_tsnreq(
665                                 struct sctp_association *asoc,
666                                 union sctp_params param,
667                                 struct sctp_ulpevent **evp)
668 {
669         __u32 init_tsn = 0, next_tsn = 0, max_tsn_seen;
670         struct sctp_strreset_tsnreq *tsnreq = param.v;
671         struct sctp_stream *stream = &asoc->stream;
672         __u32 result = SCTP_STRRESET_DENIED;
673         __u32 request_seq;
674         __u16 i;
675
676         request_seq = ntohl(tsnreq->request_seq);
677         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
678             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
679                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
680                 goto err;
681         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
682                 i = asoc->strreset_inseq - request_seq - 1;
683                 result = asoc->strreset_result[i];
684                 if (result == SCTP_STRRESET_PERFORMED) {
685                         next_tsn = asoc->ctsn_ack_point + 1;
686                         init_tsn =
687                                 sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + 1;
688                 }
689                 goto err;
690         }
691
692         if (!sctp_outq_is_empty(&asoc->outqueue)) {
693                 result = SCTP_STRRESET_IN_PROGRESS;
694                 goto err;
695         }
696
697         asoc->strreset_inseq++;
698
699         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
700                 goto out;
701
702         if (asoc->strreset_outstanding) {
703                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
704                 goto out;
705         }
706
707         /* G4: The same processing as though a FWD-TSN chunk (as defined in
708          *     [RFC3758]) with all streams affected and a new cumulative TSN
709          *     ACK of the Receiver's Next TSN minus 1 were received MUST be
710          *     performed.
711          */
712         max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
713         asoc->stream.si->report_ftsn(&asoc->ulpq, max_tsn_seen);
714
715         /* G1: Compute an appropriate value for the Receiver's Next TSN -- the
716          *     TSN that the peer should use to send the next DATA chunk.  The
717          *     value SHOULD be the smallest TSN not acknowledged by the
718          *     receiver of the request plus 2^31.
719          */
720         init_tsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + (1 << 31);
721         sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
722                          init_tsn, GFP_ATOMIC);
723
724         /* G3: The same processing as though a SACK chunk with no gap report
725          *     and a cumulative TSN ACK of the Sender's Next TSN minus 1 were
726          *     received MUST be performed.
727          */
728         sctp_outq_free(&asoc->outqueue);
729
730         /* G2: Compute an appropriate value for the local endpoint's next TSN,
731          *     i.e., the next TSN assigned by the receiver of the SSN/TSN reset
732          *     chunk.  The value SHOULD be the highest TSN sent by the receiver
733          *     of the request plus 1.
734          */
735         next_tsn = asoc->next_tsn;
736         asoc->ctsn_ack_point = next_tsn - 1;
737         asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
738
739         /* G5:  The next expected and outgoing SSNs MUST be reset to 0 for all
740          *      incoming and outgoing streams.
741          */
742         for (i = 0; i < stream->outcnt; i++) {
743                 SCTP_SO(stream, i)->mid = 0;
744                 SCTP_SO(stream, i)->mid_uo = 0;
745         }
746         for (i = 0; i < stream->incnt; i++)
747                 SCTP_SI(stream, i)->mid = 0;
748
749         result = SCTP_STRRESET_PERFORMED;
750
751         *evp = sctp_ulpevent_make_assoc_reset_event(asoc, 0, init_tsn,
752                                                     next_tsn, GFP_ATOMIC);
753
754 out:
755         sctp_update_strreset_result(asoc, result);
756 err:
757         return sctp_make_strreset_tsnresp(asoc, result, request_seq,
758                                           next_tsn, init_tsn);
759 }
760
761 struct sctp_chunk *sctp_process_strreset_addstrm_out(
762                                 struct sctp_association *asoc,
763                                 union sctp_params param,
764                                 struct sctp_ulpevent **evp)
765 {
766         struct sctp_strreset_addstrm *addstrm = param.v;
767         struct sctp_stream *stream = &asoc->stream;
768         __u32 result = SCTP_STRRESET_DENIED;
769         __u32 request_seq, incnt;
770         __u16 in, i;
771
772         request_seq = ntohl(addstrm->request_seq);
773         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
774             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
775                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
776                 goto err;
777         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
778                 i = asoc->strreset_inseq - request_seq - 1;
779                 result = asoc->strreset_result[i];
780                 goto err;
781         }
782         asoc->strreset_inseq++;
783
784         if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
785                 goto out;
786
787         in = ntohs(addstrm->number_of_streams);
788         incnt = stream->incnt + in;
789         if (!in || incnt > SCTP_MAX_STREAM)
790                 goto out;
791
792         if (sctp_stream_alloc_in(stream, incnt, GFP_ATOMIC))
793                 goto out;
794
795         if (asoc->strreset_chunk) {
796                 if (!sctp_chunk_lookup_strreset_param(
797                         asoc, 0, SCTP_PARAM_RESET_ADD_IN_STREAMS)) {
798                         /* same process with outstanding isn't 0 */
799                         result = SCTP_STRRESET_ERR_IN_PROGRESS;
800                         goto out;
801                 }
802
803                 asoc->strreset_outstanding--;
804                 asoc->strreset_outseq++;
805
806                 if (!asoc->strreset_outstanding) {
807                         struct sctp_transport *t;
808
809                         t = asoc->strreset_chunk->transport;
810                         if (del_timer(&t->reconf_timer))
811                                 sctp_transport_put(t);
812
813                         sctp_chunk_put(asoc->strreset_chunk);
814                         asoc->strreset_chunk = NULL;
815                 }
816         }
817
818         stream->incnt = incnt;
819
820         result = SCTP_STRRESET_PERFORMED;
821
822         *evp = sctp_ulpevent_make_stream_change_event(asoc,
823                 0, ntohs(addstrm->number_of_streams), 0, GFP_ATOMIC);
824
825 out:
826         sctp_update_strreset_result(asoc, result);
827 err:
828         return sctp_make_strreset_resp(asoc, result, request_seq);
829 }
830
831 struct sctp_chunk *sctp_process_strreset_addstrm_in(
832                                 struct sctp_association *asoc,
833                                 union sctp_params param,
834                                 struct sctp_ulpevent **evp)
835 {
836         struct sctp_strreset_addstrm *addstrm = param.v;
837         struct sctp_stream *stream = &asoc->stream;
838         __u32 result = SCTP_STRRESET_DENIED;
839         struct sctp_chunk *chunk = NULL;
840         __u32 request_seq, outcnt;
841         __u16 out, i;
842         int ret;
843
844         request_seq = ntohl(addstrm->request_seq);
845         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
846             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
847                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
848                 goto err;
849         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
850                 i = asoc->strreset_inseq - request_seq - 1;
851                 result = asoc->strreset_result[i];
852                 if (result == SCTP_STRRESET_PERFORMED)
853                         return NULL;
854                 goto err;
855         }
856         asoc->strreset_inseq++;
857
858         if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
859                 goto out;
860
861         if (asoc->strreset_outstanding) {
862                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
863                 goto out;
864         }
865
866         out = ntohs(addstrm->number_of_streams);
867         outcnt = stream->outcnt + out;
868         if (!out || outcnt > SCTP_MAX_STREAM)
869                 goto out;
870
871         ret = sctp_stream_alloc_out(stream, outcnt, GFP_ATOMIC);
872         if (ret)
873                 goto out;
874
875         chunk = sctp_make_strreset_addstrm(asoc, out, 0);
876         if (!chunk)
877                 goto out;
878
879         asoc->strreset_chunk = chunk;
880         asoc->strreset_outstanding = 1;
881         sctp_chunk_hold(asoc->strreset_chunk);
882
883         stream->outcnt = outcnt;
884
885         result = SCTP_STRRESET_PERFORMED;
886
887 out:
888         sctp_update_strreset_result(asoc, result);
889 err:
890         if (!chunk)
891                 chunk = sctp_make_strreset_resp(asoc, result, request_seq);
892
893         return chunk;
894 }
895
896 struct sctp_chunk *sctp_process_strreset_resp(
897                                 struct sctp_association *asoc,
898                                 union sctp_params param,
899                                 struct sctp_ulpevent **evp)
900 {
901         struct sctp_stream *stream = &asoc->stream;
902         struct sctp_strreset_resp *resp = param.v;
903         struct sctp_transport *t;
904         __u16 i, nums, flags = 0;
905         struct sctp_paramhdr *req;
906         __u32 result;
907
908         req = sctp_chunk_lookup_strreset_param(asoc, resp->response_seq, 0);
909         if (!req)
910                 return NULL;
911
912         result = ntohl(resp->result);
913         if (result != SCTP_STRRESET_PERFORMED) {
914                 /* if in progress, do nothing but retransmit */
915                 if (result == SCTP_STRRESET_IN_PROGRESS)
916                         return NULL;
917                 else if (result == SCTP_STRRESET_DENIED)
918                         flags = SCTP_STREAM_RESET_DENIED;
919                 else
920                         flags = SCTP_STREAM_RESET_FAILED;
921         }
922
923         if (req->type == SCTP_PARAM_RESET_OUT_REQUEST) {
924                 struct sctp_strreset_outreq *outreq;
925                 __be16 *str_p;
926
927                 outreq = (struct sctp_strreset_outreq *)req;
928                 str_p = outreq->list_of_streams;
929                 nums = (ntohs(outreq->param_hdr.length) - sizeof(*outreq)) /
930                        sizeof(__u16);
931
932                 if (result == SCTP_STRRESET_PERFORMED) {
933                         struct sctp_stream_out *sout;
934                         if (nums) {
935                                 for (i = 0; i < nums; i++) {
936                                         sout = SCTP_SO(stream, ntohs(str_p[i]));
937                                         sout->mid = 0;
938                                         sout->mid_uo = 0;
939                                 }
940                         } else {
941                                 for (i = 0; i < stream->outcnt; i++) {
942                                         sout = SCTP_SO(stream, i);
943                                         sout->mid = 0;
944                                         sout->mid_uo = 0;
945                                 }
946                         }
947                 }
948
949                 flags |= SCTP_STREAM_RESET_OUTGOING_SSN;
950
951                 for (i = 0; i < stream->outcnt; i++)
952                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
953
954                 *evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
955                         nums, str_p, GFP_ATOMIC);
956         } else if (req->type == SCTP_PARAM_RESET_IN_REQUEST) {
957                 struct sctp_strreset_inreq *inreq;
958                 __be16 *str_p;
959
960                 /* if the result is performed, it's impossible for inreq */
961                 if (result == SCTP_STRRESET_PERFORMED)
962                         return NULL;
963
964                 inreq = (struct sctp_strreset_inreq *)req;
965                 str_p = inreq->list_of_streams;
966                 nums = (ntohs(inreq->param_hdr.length) - sizeof(*inreq)) /
967                        sizeof(__u16);
968
969                 flags |= SCTP_STREAM_RESET_INCOMING_SSN;
970
971                 *evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
972                         nums, str_p, GFP_ATOMIC);
973         } else if (req->type == SCTP_PARAM_RESET_TSN_REQUEST) {
974                 struct sctp_strreset_resptsn *resptsn;
975                 __u32 stsn, rtsn;
976
977                 /* check for resptsn, as sctp_verify_reconf didn't do it*/
978                 if (ntohs(param.p->length) != sizeof(*resptsn))
979                         return NULL;
980
981                 resptsn = (struct sctp_strreset_resptsn *)resp;
982                 stsn = ntohl(resptsn->senders_next_tsn);
983                 rtsn = ntohl(resptsn->receivers_next_tsn);
984
985                 if (result == SCTP_STRRESET_PERFORMED) {
986                         __u32 mtsn = sctp_tsnmap_get_max_tsn_seen(
987                                                 &asoc->peer.tsn_map);
988                         LIST_HEAD(temp);
989
990                         asoc->stream.si->report_ftsn(&asoc->ulpq, mtsn);
991
992                         sctp_tsnmap_init(&asoc->peer.tsn_map,
993                                          SCTP_TSN_MAP_INITIAL,
994                                          stsn, GFP_ATOMIC);
995
996                         /* Clean up sacked and abandoned queues only. As the
997                          * out_chunk_list may not be empty, splice it to temp,
998                          * then get it back after sctp_outq_free is done.
999                          */
1000                         list_splice_init(&asoc->outqueue.out_chunk_list, &temp);
1001                         sctp_outq_free(&asoc->outqueue);
1002                         list_splice_init(&temp, &asoc->outqueue.out_chunk_list);
1003
1004                         asoc->next_tsn = rtsn;
1005                         asoc->ctsn_ack_point = asoc->next_tsn - 1;
1006                         asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
1007
1008                         for (i = 0; i < stream->outcnt; i++) {
1009                                 SCTP_SO(stream, i)->mid = 0;
1010                                 SCTP_SO(stream, i)->mid_uo = 0;
1011                         }
1012                         for (i = 0; i < stream->incnt; i++)
1013                                 SCTP_SI(stream, i)->mid = 0;
1014                 }
1015
1016                 for (i = 0; i < stream->outcnt; i++)
1017                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
1018
1019                 *evp = sctp_ulpevent_make_assoc_reset_event(asoc, flags,
1020                         stsn, rtsn, GFP_ATOMIC);
1021         } else if (req->type == SCTP_PARAM_RESET_ADD_OUT_STREAMS) {
1022                 struct sctp_strreset_addstrm *addstrm;
1023                 __u16 number;
1024
1025                 addstrm = (struct sctp_strreset_addstrm *)req;
1026                 nums = ntohs(addstrm->number_of_streams);
1027                 number = stream->outcnt - nums;
1028
1029                 if (result == SCTP_STRRESET_PERFORMED)
1030                         for (i = number; i < stream->outcnt; i++)
1031                                 SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
1032                 else
1033                         stream->outcnt = number;
1034
1035                 *evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1036                         0, nums, GFP_ATOMIC);
1037         } else if (req->type == SCTP_PARAM_RESET_ADD_IN_STREAMS) {
1038                 struct sctp_strreset_addstrm *addstrm;
1039
1040                 /* if the result is performed, it's impossible for addstrm in
1041                  * request.
1042                  */
1043                 if (result == SCTP_STRRESET_PERFORMED)
1044                         return NULL;
1045
1046                 addstrm = (struct sctp_strreset_addstrm *)req;
1047                 nums = ntohs(addstrm->number_of_streams);
1048
1049                 *evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1050                         nums, 0, GFP_ATOMIC);
1051         }
1052
1053         asoc->strreset_outstanding--;
1054         asoc->strreset_outseq++;
1055
1056         /* remove everything for this reconf request */
1057         if (!asoc->strreset_outstanding) {
1058                 t = asoc->strreset_chunk->transport;
1059                 if (del_timer(&t->reconf_timer))
1060                         sctp_transport_put(t);
1061
1062                 sctp_chunk_put(asoc->strreset_chunk);
1063                 asoc->strreset_chunk = NULL;
1064         }
1065
1066         return NULL;
1067 }