net/sctp/stream.c

   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  * This file contains sctp stream maniuplation primitives and helpers.
  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 static struct flex_array *fa_alloc(size_t elem_size, size_t elem_count,
  41                                    gfp_t gfp)
  42 {
  43         struct flex_array *result;
  44         int err;
  45
  46         result = flex_array_alloc(elem_size, elem_count, gfp);
  47         if (result) {
  48                 err = flex_array_prealloc(result, 0, elem_count, gfp);
  49                 if (err) {
  50                         flex_array_free(result);
  51                         result = NULL;
  52                 }
  53         }
  54
  55         return result;
  56 }
  57
  58 static void fa_free(struct flex_array *fa)
  59 {
  60         if (fa)
  61                 flex_array_free(fa);
  62 }
  63
  64 static void fa_copy(struct flex_array *fa, struct flex_array *from,
  65                     size_t index, size_t count)
  66 {
  67         void *elem;
  68
  69         while (count--) {
  70                 elem = flex_array_get(from, index);
  71                 flex_array_put(fa, index, elem, 0);
  72                 index++;
  73         }
  74 }
  75
  76 static void fa_zero(struct flex_array *fa, size_t index, size_t count)
  77 {
  78         void *elem;
  79
  80         while (count--) {
  81                 elem = flex_array_get(fa, index);
  82                 memset(elem, 0, fa->element_size);
  83                 index++;
  84         }
  85 }
  86
  87 /* Migrates chunks from stream queues to new stream queues if needed,
  88  * but not across associations. Also, removes those chunks to streams
  89  * higher than the new max.
  90  */
  91 static void sctp_stream_outq_migrate(struct sctp_stream *stream,
  92                                      struct sctp_stream *new, __u16 outcnt)
  93 {
  94         struct sctp_association *asoc;
  95         struct sctp_chunk *ch, *temp;
  96         struct sctp_outq *outq;
  97         int i;
  98
  99         asoc = container_of(stream, struct sctp_association, stream);
 100         outq = &asoc->outqueue;
 101
 102         list_for_each_entry_safe(ch, temp, &outq->out_chunk_list, list) {
 103                 __u16 sid = sctp_chunk_stream_no(ch);
 104
 105                 if (sid < outcnt)
 106                         continue;
 107
 108                 sctp_sched_dequeue_common(outq, ch);
 109                 /* No need to call dequeue_done here because
 110                  * the chunks are not scheduled by now.
 111                  */
 112
 113                 /* Mark as failed send. */
 114                 sctp_chunk_fail(ch, (__force __u32)SCTP_ERROR_INV_STRM);
 115                 if (asoc->peer.prsctp_capable &&
 116                     SCTP_PR_PRIO_ENABLED(ch->sinfo.sinfo_flags))
 117                         asoc->sent_cnt_removable--;
 118
 119                 sctp_chunk_free(ch);
 120         }
 121
 122         if (new) {
 123                 /* Here we actually move the old ext stuff into the new
 124                  * buffer, because we want to keep it. Then
 125                  * sctp_stream_update will swap ->out pointers.
 126                  */
 127                 for (i = 0; i < outcnt; i++) {
 128                         kfree(SCTP_SO(new, i)->ext);
 129                         SCTP_SO(new, i)->ext = SCTP_SO(stream, i)->ext;
 130                         SCTP_SO(stream, i)->ext = NULL;
 131                 }
 132         }
 133
 134         for (i = outcnt; i < stream->outcnt; i++)
 135                 kfree(SCTP_SO(stream, i)->ext);
 136 }
 137
 138 static int sctp_stream_alloc_out(struct sctp_stream *stream, __u16 outcnt,
 139                                  gfp_t gfp)
 140 {
 141         struct flex_array *out;
 142         size_t elem_size = sizeof(struct sctp_stream_out);
 143
 144         out = fa_alloc(elem_size, outcnt, gfp);
 145         if (!out)
 146                 return -ENOMEM;
 147
 148         if (stream->out) {
 149                 fa_copy(out, stream->out, 0, min(outcnt, stream->outcnt));
 150                 fa_free(stream->out);
 151         }
 152
 153         if (outcnt > stream->outcnt)
 154                 fa_zero(out, stream->outcnt, (outcnt - stream->outcnt));
 155
 156         stream->out = out;
 157
 158         return 0;
 159 }
 160
 161 static int sctp_stream_alloc_in(struct sctp_stream *stream, __u16 incnt,
 162                                 gfp_t gfp)
 163 {
 164         struct flex_array *in;
 165         size_t elem_size = sizeof(struct sctp_stream_in);
 166
 167         in = fa_alloc(elem_size, incnt, gfp);
 168         if (!in)
 169                 return -ENOMEM;
 170
 171         if (stream->in) {
 172                 fa_copy(in, stream->in, 0, min(incnt, stream->incnt));
 173                 fa_free(stream->in);
 174         }
 175
 176         if (incnt > stream->incnt)
 177                 fa_zero(in, stream->incnt, (incnt - stream->incnt));
 178
 179         stream->in = in;
 180
 181         return 0;
 182 }
 183
 184 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt,
 185                      gfp_t gfp)
 186 {
 187         struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
 188         int i, ret = 0;
 189
 190         gfp |= __GFP_NOWARN;
 191
 192         /* Initial stream->out size may be very big, so free it and alloc
 193          * a new one with new outcnt to save memory if needed.
 194          */
 195         if (outcnt == stream->outcnt)
 196                 goto in;
 197
 198         /* Filter out chunks queued on streams that won't exist anymore */
 199         sched->unsched_all(stream);
 200         sctp_stream_outq_migrate(stream, NULL, outcnt);
 201         sched->sched_all(stream);
 202
 203         ret = sctp_stream_alloc_out(stream, outcnt, gfp);
 204         if (ret)
 205                 goto out;
 206
 207         stream->outcnt = outcnt;
 208         for (i = 0; i < stream->outcnt; i++)
 209                 SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
 210
 211         sched->init(stream);
 212
 213 in:
 214         sctp_stream_interleave_init(stream);
 215         if (!incnt)
 216                 goto out;
 217
 218         ret = sctp_stream_alloc_in(stream, incnt, gfp);
 219         if (ret) {
 220                 sched->free(stream);
 221                 fa_free(stream->out);
 222                 stream->out = NULL;
 223                 stream->outcnt = 0;
 224                 goto out;
 225         }
 226
 227         stream->incnt = incnt;
 228
 229 out:
 230         return ret;
 231 }
 232
 233 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid)
 234 {
 235         struct sctp_stream_out_ext *soute;
 236
 237         soute = kzalloc(sizeof(*soute), GFP_KERNEL);
 238         if (!soute)
 239                 return -ENOMEM;
 240         SCTP_SO(stream, sid)->ext = soute;
 241
 242         return sctp_sched_init_sid(stream, sid, GFP_KERNEL);
 243 }
 244
 245 void sctp_stream_free(struct sctp_stream *stream)
 246 {
 247         struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
 248         int i;
 249
 250         sched->free(stream);
 251         for (i = 0; i < stream->outcnt; i++)
 252                 kfree(SCTP_SO(stream, i)->ext);
 253         fa_free(stream->out);
 254         fa_free(stream->in);
 255 }
 256
 257 void sctp_stream_clear(struct sctp_stream *stream)
 258 {
 259         int i;
 260
 261         for (i = 0; i < stream->outcnt; i++) {
 262                 SCTP_SO(stream, i)->mid = 0;
 263                 SCTP_SO(stream, i)->mid_uo = 0;
 264         }
 265
 266         for (i = 0; i < stream->incnt; i++)
 267                 SCTP_SI(stream, i)->mid = 0;
 268 }
 269
 270 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new)
 271 {
 272         struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
 273
 274         sched->unsched_all(stream);
 275         sctp_stream_outq_migrate(stream, new, new->outcnt);
 276         sctp_stream_free(stream);
 277
 278         stream->out = new->out;
 279         stream->in  = new->in;
 280         stream->outcnt = new->outcnt;
 281         stream->incnt  = new->incnt;
 282
 283         sched->sched_all(stream);
 284
 285         new->out = NULL;
 286         new->in  = NULL;
 287         new->outcnt = 0;
 288         new->incnt  = 0;
 289 }
 290
 291 static int sctp_send_reconf(struct sctp_association *asoc,
 292                             struct sctp_chunk *chunk)
 293 {
 294         struct net *net = sock_net(asoc->base.sk);
 295         int retval = 0;
 296
 297         retval = sctp_primitive_RECONF(net, asoc, chunk);
 298         if (retval)
 299                 sctp_chunk_free(chunk);
 300
 301         return retval;
 302 }
 303
 304 static bool sctp_stream_outq_is_empty(struct sctp_stream *stream,
 305                                       __u16 str_nums, __be16 *str_list)
 306 {
 307         struct sctp_association *asoc;
 308         __u16 i;
 309
 310         asoc = container_of(stream, struct sctp_association, stream);
 311         if (!asoc->outqueue.out_qlen)
 312                 return true;
 313
 314         if (!str_nums)
 315                 return false;
 316
 317         for (i = 0; i < str_nums; i++) {
 318                 __u16 sid = ntohs(str_list[i]);
 319
 320                 if (SCTP_SO(stream, sid)->ext &&
 321                     !list_empty(&SCTP_SO(stream, sid)->ext->outq))
 322                         return false;
 323         }
 324
 325         return true;
 326 }
 327
 328 int sctp_send_reset_streams(struct sctp_association *asoc,
 329                             struct sctp_reset_streams *params)
 330 {
 331         struct sctp_stream *stream = &asoc->stream;
 332         __u16 i, str_nums, *str_list;
 333         struct sctp_chunk *chunk;
 334         int retval = -EINVAL;
 335         __be16 *nstr_list;
 336         bool out, in;
 337
 338         if (!asoc->peer.reconf_capable ||
 339             !(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ)) {
 340                 retval = -ENOPROTOOPT;
 341                 goto out;
 342         }
 343
 344         if (asoc->strreset_outstanding) {
 345                 retval = -EINPROGRESS;
 346                 goto out;
 347         }
 348
 349         out = params->srs_flags & SCTP_STREAM_RESET_OUTGOING;
 350         in  = params->srs_flags & SCTP_STREAM_RESET_INCOMING;
 351         if (!out && !in)
 352                 goto out;
 353
 354         str_nums = params->srs_number_streams;
 355         str_list = params->srs_stream_list;
 356         if (str_nums) {
 357                 int param_len = 0;
 358
 359                 if (out) {
 360                         for (i = 0; i < str_nums; i++)
 361                                 if (str_list[i] >= stream->outcnt)
 362                                         goto out;
 363
 364                         param_len = str_nums * sizeof(__u16) +
 365                                     sizeof(struct sctp_strreset_outreq);
 366                 }
 367
 368                 if (in) {
 369                         for (i = 0; i < str_nums; i++)
 370                                 if (str_list[i] >= stream->incnt)
 371                                         goto out;
 372
 373                         param_len += str_nums * sizeof(__u16) +
 374                                      sizeof(struct sctp_strreset_inreq);
 375                 }
 376
 377                 if (param_len > SCTP_MAX_CHUNK_LEN -
 378                                 sizeof(struct sctp_reconf_chunk))
 379                         goto out;
 380         }
 381
 382         nstr_list = kcalloc(str_nums, sizeof(__be16), GFP_KERNEL);
 383         if (!nstr_list) {
 384                 retval = -ENOMEM;
 385                 goto out;
 386         }
 387
 388         for (i = 0; i < str_nums; i++)
 389                 nstr_list[i] = htons(str_list[i]);
 390
 391         if (out && !sctp_stream_outq_is_empty(stream, str_nums, nstr_list)) {
 392                 retval = -EAGAIN;
 393                 goto out;
 394         }
 395
 396         chunk = sctp_make_strreset_req(asoc, str_nums, nstr_list, out, in);
 397
 398         kfree(nstr_list);
 399
 400         if (!chunk) {
 401                 retval = -ENOMEM;
 402                 goto out;
 403         }
 404
 405         if (out) {
 406                 if (str_nums)
 407                         for (i = 0; i < str_nums; i++)
 408                                 SCTP_SO(stream, str_list[i])->state =
 409                                                        SCTP_STREAM_CLOSED;
 410                 else
 411                         for (i = 0; i < stream->outcnt; i++)
 412                                 SCTP_SO(stream, i)->state = SCTP_STREAM_CLOSED;
 413         }
 414
 415         asoc->strreset_chunk = chunk;
 416         sctp_chunk_hold(asoc->strreset_chunk);
 417
 418         retval = sctp_send_reconf(asoc, chunk);
 419         if (retval) {
 420                 sctp_chunk_put(asoc->strreset_chunk);
 421                 asoc->strreset_chunk = NULL;
 422                 if (!out)
 423                         goto out;
 424
 425                 if (str_nums)
 426                         for (i = 0; i < str_nums; i++)
 427                                 SCTP_SO(stream, str_list[i])->state =
 428                                                        SCTP_STREAM_OPEN;
 429                 else
 430                         for (i = 0; i < stream->outcnt; i++)
 431                                 SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
 432
 433                 goto out;
 434         }
 435
 436         asoc->strreset_outstanding = out + in;
 437
 438 out:
 439         return retval;
 440 }
 441
 442 int sctp_send_reset_assoc(struct sctp_association *asoc)
 443 {
 444         struct sctp_stream *stream = &asoc->stream;
 445         struct sctp_chunk *chunk = NULL;
 446         int retval;
 447         __u16 i;
 448
 449         if (!asoc->peer.reconf_capable ||
 450             !(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
 451                 return -ENOPROTOOPT;
 452
 453         if (asoc->strreset_outstanding)
 454                 return -EINPROGRESS;
 455
 456         if (!sctp_outq_is_empty(&asoc->outqueue))
 457                 return -EAGAIN;
 458
 459         chunk = sctp_make_strreset_tsnreq(asoc);
 460         if (!chunk)
 461                 return -ENOMEM;
 462
 463         /* Block further xmit of data until this request is completed */
 464         for (i = 0; i < stream->outcnt; i++)
 465                 SCTP_SO(stream, i)->state = SCTP_STREAM_CLOSED;
 466
 467         asoc->strreset_chunk = chunk;
 468         sctp_chunk_hold(asoc->strreset_chunk);
 469
 470         retval = sctp_send_reconf(asoc, chunk);
 471         if (retval) {
 472                 sctp_chunk_put(asoc->strreset_chunk);
 473                 asoc->strreset_chunk = NULL;
 474
 475                 for (i = 0; i < stream->outcnt; i++)
 476                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
 477
 478                 return retval;
 479         }
 480
 481         asoc->strreset_outstanding = 1;
 482
 483         return 0;
 484 }
 485
 486 int sctp_send_add_streams(struct sctp_association *asoc,
 487                           struct sctp_add_streams *params)
 488 {
 489         struct sctp_stream *stream = &asoc->stream;
 490         struct sctp_chunk *chunk = NULL;
 491         int retval;
 492         __u32 outcnt, incnt;
 493         __u16 out, in;
 494
 495         if (!asoc->peer.reconf_capable ||
 496             !(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ)) {
 497                 retval = -ENOPROTOOPT;
 498                 goto out;
 499         }
 500
 501         if (asoc->strreset_outstanding) {
 502                 retval = -EINPROGRESS;
 503                 goto out;
 504         }
 505
 506         out = params->sas_outstrms;
 507         in  = params->sas_instrms;
 508         outcnt = stream->outcnt + out;
 509         incnt = stream->incnt + in;
 510         if (outcnt > SCTP_MAX_STREAM || incnt > SCTP_MAX_STREAM ||
 511             (!out && !in)) {
 512                 retval = -EINVAL;
 513                 goto out;
 514         }
 515
 516         if (out) {
 517                 retval = sctp_stream_alloc_out(stream, outcnt, GFP_KERNEL);
 518                 if (retval)
 519                         goto out;
 520         }
 521
 522         chunk = sctp_make_strreset_addstrm(asoc, out, in);
 523         if (!chunk) {
 524                 retval = -ENOMEM;
 525                 goto out;
 526         }
 527
 528         asoc->strreset_chunk = chunk;
 529         sctp_chunk_hold(asoc->strreset_chunk);
 530
 531         retval = sctp_send_reconf(asoc, chunk);
 532         if (retval) {
 533                 sctp_chunk_put(asoc->strreset_chunk);
 534                 asoc->strreset_chunk = NULL;
 535                 goto out;
 536         }
 537
 538         stream->incnt = incnt;
 539         stream->outcnt = outcnt;
 540
 541         asoc->strreset_outstanding = !!out + !!in;
 542
 543 out:
 544         return retval;
 545 }
 546
 547 static struct sctp_paramhdr *sctp_chunk_lookup_strreset_param(
 548                         struct sctp_association *asoc, __be32 resp_seq,
 549                         __be16 type)
 550 {
 551         struct sctp_chunk *chunk = asoc->strreset_chunk;
 552         struct sctp_reconf_chunk *hdr;
 553         union sctp_params param;
 554
 555         if (!chunk)
 556                 return NULL;
 557
 558         hdr = (struct sctp_reconf_chunk *)chunk->chunk_hdr;
 559         sctp_walk_params(param, hdr, params) {
 560                 /* sctp_strreset_tsnreq is actually the basic structure
 561                  * of all stream reconf params, so it's safe to use it
 562                  * to access request_seq.
 563                  */
 564                 struct sctp_strreset_tsnreq *req = param.v;
 565
 566                 if ((!resp_seq || req->request_seq == resp_seq) &&
 567                     (!type || type == req->param_hdr.type))
 568                         return param.v;
 569         }
 570
 571         return NULL;
 572 }
 573
 574 static void sctp_update_strreset_result(struct sctp_association *asoc,
 575                                         __u32 result)
 576 {
 577         asoc->strreset_result[1] = asoc->strreset_result[0];
 578         asoc->strreset_result[0] = result;
 579 }
 580
 581 struct sctp_chunk *sctp_process_strreset_outreq(
 582                                 struct sctp_association *asoc,
 583                                 union sctp_params param,
 584                                 struct sctp_ulpevent **evp)
 585 {
 586         struct sctp_strreset_outreq *outreq = param.v;
 587         struct sctp_stream *stream = &asoc->stream;
 588         __u32 result = SCTP_STRRESET_DENIED;
 589         __u16 i, nums, flags = 0;
 590         __be16 *str_p = NULL;
 591         __u32 request_seq;
 592
 593         request_seq = ntohl(outreq->request_seq);
 594
 595         if (ntohl(outreq->send_reset_at_tsn) >
 596             sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map)) {
 597                 result = SCTP_STRRESET_IN_PROGRESS;
 598                 goto err;
 599         }
 600
 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                 goto err;
 609         }
 610         asoc->strreset_inseq++;
 611
 612         /* Check strreset_enable after inseq inc, as sender cannot tell
 613          * the peer doesn't enable strreset after receiving response with
 614          * result denied, as well as to keep consistent with bsd.
 615          */
 616         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
 617                 goto out;
 618
 619         if (asoc->strreset_chunk) {
 620                 if (!sctp_chunk_lookup_strreset_param(
 621                                 asoc, outreq->response_seq,
 622                                 SCTP_PARAM_RESET_IN_REQUEST)) {
 623                         /* same process with outstanding isn't 0 */
 624                         result = SCTP_STRRESET_ERR_IN_PROGRESS;
 625                         goto out;
 626                 }
 627
 628                 asoc->strreset_outstanding--;
 629                 asoc->strreset_outseq++;
 630
 631                 if (!asoc->strreset_outstanding) {
 632                         struct sctp_transport *t;
 633
 634                         t = asoc->strreset_chunk->transport;
 635                         if (del_timer(&t->reconf_timer))
 636                                 sctp_transport_put(t);
 637
 638                         sctp_chunk_put(asoc->strreset_chunk);
 639                         asoc->strreset_chunk = NULL;
 640                 }
 641
 642                 flags = SCTP_STREAM_RESET_INCOMING_SSN;
 643         }
 644
 645         nums = (ntohs(param.p->length) - sizeof(*outreq)) / sizeof(__u16);
 646         if (nums) {
 647                 str_p = outreq->list_of_streams;
 648                 for (i = 0; i < nums; i++) {
 649                         if (ntohs(str_p[i]) >= stream->incnt) {
 650                                 result = SCTP_STRRESET_ERR_WRONG_SSN;
 651                                 goto out;
 652                         }
 653                 }
 654
 655                 for (i = 0; i < nums; i++)
 656                         SCTP_SI(stream, ntohs(str_p[i]))->mid = 0;
 657         } else {
 658                 for (i = 0; i < stream->incnt; i++)
 659                         SCTP_SI(stream, i)->mid = 0;
 660         }
 661
 662         result = SCTP_STRRESET_PERFORMED;
 663
 664         *evp = sctp_ulpevent_make_stream_reset_event(asoc,
 665                 flags | SCTP_STREAM_RESET_OUTGOING_SSN, nums, str_p,
 666                 GFP_ATOMIC);
 667
 668 out:
 669         sctp_update_strreset_result(asoc, result);
 670 err:
 671         return sctp_make_strreset_resp(asoc, result, request_seq);
 672 }
 673
 674 struct sctp_chunk *sctp_process_strreset_inreq(
 675                                 struct sctp_association *asoc,
 676                                 union sctp_params param,
 677                                 struct sctp_ulpevent **evp)
 678 {
 679         struct sctp_strreset_inreq *inreq = param.v;
 680         struct sctp_stream *stream = &asoc->stream;
 681         __u32 result = SCTP_STRRESET_DENIED;
 682         struct sctp_chunk *chunk = NULL;
 683         __u32 request_seq;
 684         __u16 i, nums;
 685         __be16 *str_p;
 686
 687         request_seq = ntohl(inreq->request_seq);
 688         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 689             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 690                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 691                 goto err;
 692         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 693                 i = asoc->strreset_inseq - request_seq - 1;
 694                 result = asoc->strreset_result[i];
 695                 if (result == SCTP_STRRESET_PERFORMED)
 696                         return NULL;
 697                 goto err;
 698         }
 699         asoc->strreset_inseq++;
 700
 701         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
 702                 goto out;
 703
 704         if (asoc->strreset_outstanding) {
 705                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
 706                 goto out;
 707         }
 708
 709         nums = (ntohs(param.p->length) - sizeof(*inreq)) / sizeof(__u16);
 710         str_p = inreq->list_of_streams;
 711         for (i = 0; i < nums; i++) {
 712                 if (ntohs(str_p[i]) >= stream->outcnt) {
 713                         result = SCTP_STRRESET_ERR_WRONG_SSN;
 714                         goto out;
 715                 }
 716         }
 717
 718         if (!sctp_stream_outq_is_empty(stream, nums, str_p)) {
 719                 result = SCTP_STRRESET_IN_PROGRESS;
 720                 asoc->strreset_inseq--;
 721                 goto err;
 722         }
 723
 724         chunk = sctp_make_strreset_req(asoc, nums, str_p, 1, 0);
 725         if (!chunk)
 726                 goto out;
 727
 728         if (nums)
 729                 for (i = 0; i < nums; i++)
 730                         SCTP_SO(stream, ntohs(str_p[i]))->state =
 731                                                SCTP_STREAM_CLOSED;
 732         else
 733                 for (i = 0; i < stream->outcnt; i++)
 734                         SCTP_SO(stream, i)->state = SCTP_STREAM_CLOSED;
 735
 736         asoc->strreset_chunk = chunk;
 737         asoc->strreset_outstanding = 1;
 738         sctp_chunk_hold(asoc->strreset_chunk);
 739
 740         result = SCTP_STRRESET_PERFORMED;
 741
 742         *evp = sctp_ulpevent_make_stream_reset_event(asoc,
 743                 SCTP_STREAM_RESET_INCOMING_SSN, nums, str_p, GFP_ATOMIC);
 744
 745 out:
 746         sctp_update_strreset_result(asoc, result);
 747 err:
 748         if (!chunk)
 749                 chunk =  sctp_make_strreset_resp(asoc, result, request_seq);
 750
 751         return chunk;
 752 }
 753
 754 struct sctp_chunk *sctp_process_strreset_tsnreq(
 755                                 struct sctp_association *asoc,
 756                                 union sctp_params param,
 757                                 struct sctp_ulpevent **evp)
 758 {
 759         __u32 init_tsn = 0, next_tsn = 0, max_tsn_seen;
 760         struct sctp_strreset_tsnreq *tsnreq = param.v;
 761         struct sctp_stream *stream = &asoc->stream;
 762         __u32 result = SCTP_STRRESET_DENIED;
 763         __u32 request_seq;
 764         __u16 i;
 765
 766         request_seq = ntohl(tsnreq->request_seq);
 767         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 768             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 769                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 770                 goto err;
 771         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 772                 i = asoc->strreset_inseq - request_seq - 1;
 773                 result = asoc->strreset_result[i];
 774                 if (result == SCTP_STRRESET_PERFORMED) {
 775                         next_tsn = asoc->ctsn_ack_point + 1;
 776                         init_tsn =
 777                                 sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + 1;
 778                 }
 779                 goto err;
 780         }
 781
 782         if (!sctp_outq_is_empty(&asoc->outqueue)) {
 783                 result = SCTP_STRRESET_IN_PROGRESS;
 784                 goto err;
 785         }
 786
 787         asoc->strreset_inseq++;
 788
 789         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
 790                 goto out;
 791
 792         if (asoc->strreset_outstanding) {
 793                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
 794                 goto out;
 795         }
 796
 797         /* G4: The same processing as though a FWD-TSN chunk (as defined in
 798          *     [RFC3758]) with all streams affected and a new cumulative TSN
 799          *     ACK of the Receiver's Next TSN minus 1 were received MUST be
 800          *     performed.
 801          */
 802         max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
 803         asoc->stream.si->report_ftsn(&asoc->ulpq, max_tsn_seen);
 804
 805         /* G1: Compute an appropriate value for the Receiver's Next TSN -- the
 806          *     TSN that the peer should use to send the next DATA chunk.  The
 807          *     value SHOULD be the smallest TSN not acknowledged by the
 808          *     receiver of the request plus 2^31.
 809          */
 810         init_tsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + (1 << 31);
 811         sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
 812                          init_tsn, GFP_ATOMIC);
 813
 814         /* G3: The same processing as though a SACK chunk with no gap report
 815          *     and a cumulative TSN ACK of the Sender's Next TSN minus 1 were
 816          *     received MUST be performed.
 817          */
 818         sctp_outq_free(&asoc->outqueue);
 819
 820         /* G2: Compute an appropriate value for the local endpoint's next TSN,
 821          *     i.e., the next TSN assigned by the receiver of the SSN/TSN reset
 822          *     chunk.  The value SHOULD be the highest TSN sent by the receiver
 823          *     of the request plus 1.
 824          */
 825         next_tsn = asoc->next_tsn;
 826         asoc->ctsn_ack_point = next_tsn - 1;
 827         asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
 828
 829         /* G5:  The next expected and outgoing SSNs MUST be reset to 0 for all
 830          *      incoming and outgoing streams.
 831          */
 832         for (i = 0; i < stream->outcnt; i++) {
 833                 SCTP_SO(stream, i)->mid = 0;
 834                 SCTP_SO(stream, i)->mid_uo = 0;
 835         }
 836         for (i = 0; i < stream->incnt; i++)
 837                 SCTP_SI(stream, i)->mid = 0;
 838
 839         result = SCTP_STRRESET_PERFORMED;
 840
 841         *evp = sctp_ulpevent_make_assoc_reset_event(asoc, 0, init_tsn,
 842                                                     next_tsn, GFP_ATOMIC);
 843
 844 out:
 845         sctp_update_strreset_result(asoc, result);
 846 err:
 847         return sctp_make_strreset_tsnresp(asoc, result, request_seq,
 848                                           next_tsn, init_tsn);
 849 }
 850
 851 struct sctp_chunk *sctp_process_strreset_addstrm_out(
 852                                 struct sctp_association *asoc,
 853                                 union sctp_params param,
 854                                 struct sctp_ulpevent **evp)
 855 {
 856         struct sctp_strreset_addstrm *addstrm = param.v;
 857         struct sctp_stream *stream = &asoc->stream;
 858         __u32 result = SCTP_STRRESET_DENIED;
 859         __u32 request_seq, incnt;
 860         __u16 in, i;
 861
 862         request_seq = ntohl(addstrm->request_seq);
 863         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 864             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 865                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 866                 goto err;
 867         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 868                 i = asoc->strreset_inseq - request_seq - 1;
 869                 result = asoc->strreset_result[i];
 870                 goto err;
 871         }
 872         asoc->strreset_inseq++;
 873
 874         if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
 875                 goto out;
 876
 877         if (asoc->strreset_chunk) {
 878                 if (!sctp_chunk_lookup_strreset_param(
 879                         asoc, 0, SCTP_PARAM_RESET_ADD_IN_STREAMS)) {
 880                         /* same process with outstanding isn't 0 */
 881                         result = SCTP_STRRESET_ERR_IN_PROGRESS;
 882                         goto out;
 883                 }
 884
 885                 asoc->strreset_outstanding--;
 886                 asoc->strreset_outseq++;
 887
 888                 if (!asoc->strreset_outstanding) {
 889                         struct sctp_transport *t;
 890
 891                         t = asoc->strreset_chunk->transport;
 892                         if (del_timer(&t->reconf_timer))
 893                                 sctp_transport_put(t);
 894
 895                         sctp_chunk_put(asoc->strreset_chunk);
 896                         asoc->strreset_chunk = NULL;
 897                 }
 898         }
 899
 900         in = ntohs(addstrm->number_of_streams);
 901         incnt = stream->incnt + in;
 902         if (!in || incnt > SCTP_MAX_STREAM)
 903                 goto out;
 904
 905         if (sctp_stream_alloc_in(stream, incnt, GFP_ATOMIC))
 906                 goto out;
 907
 908         stream->incnt = incnt;
 909
 910         result = SCTP_STRRESET_PERFORMED;
 911
 912         *evp = sctp_ulpevent_make_stream_change_event(asoc,
 913                 0, ntohs(addstrm->number_of_streams), 0, GFP_ATOMIC);
 914
 915 out:
 916         sctp_update_strreset_result(asoc, result);
 917 err:
 918         return sctp_make_strreset_resp(asoc, result, request_seq);
 919 }
 920
 921 struct sctp_chunk *sctp_process_strreset_addstrm_in(
 922                                 struct sctp_association *asoc,
 923                                 union sctp_params param,
 924                                 struct sctp_ulpevent **evp)
 925 {
 926         struct sctp_strreset_addstrm *addstrm = param.v;
 927         struct sctp_stream *stream = &asoc->stream;
 928         __u32 result = SCTP_STRRESET_DENIED;
 929         struct sctp_chunk *chunk = NULL;
 930         __u32 request_seq, outcnt;
 931         __u16 out, i;
 932         int ret;
 933
 934         request_seq = ntohl(addstrm->request_seq);
 935         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 936             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 937                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 938                 goto err;
 939         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 940                 i = asoc->strreset_inseq - request_seq - 1;
 941                 result = asoc->strreset_result[i];
 942                 if (result == SCTP_STRRESET_PERFORMED)
 943                         return NULL;
 944                 goto err;
 945         }
 946         asoc->strreset_inseq++;
 947
 948         if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
 949                 goto out;
 950
 951         if (asoc->strreset_outstanding) {
 952                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
 953                 goto out;
 954         }
 955
 956         out = ntohs(addstrm->number_of_streams);
 957         outcnt = stream->outcnt + out;
 958         if (!out || outcnt > SCTP_MAX_STREAM)
 959                 goto out;
 960
 961         ret = sctp_stream_alloc_out(stream, outcnt, GFP_ATOMIC);
 962         if (ret)
 963                 goto out;
 964
 965         chunk = sctp_make_strreset_addstrm(asoc, out, 0);
 966         if (!chunk)
 967                 goto out;
 968
 969         asoc->strreset_chunk = chunk;
 970         asoc->strreset_outstanding = 1;
 971         sctp_chunk_hold(asoc->strreset_chunk);
 972
 973         stream->outcnt = outcnt;
 974
 975         result = SCTP_STRRESET_PERFORMED;
 976
 977         *evp = sctp_ulpevent_make_stream_change_event(asoc,
 978                 0, 0, ntohs(addstrm->number_of_streams), GFP_ATOMIC);
 979
 980 out:
 981         sctp_update_strreset_result(asoc, result);
 982 err:
 983         if (!chunk)
 984                 chunk = sctp_make_strreset_resp(asoc, result, request_seq);
 985
 986         return chunk;
 987 }
 988
 989 struct sctp_chunk *sctp_process_strreset_resp(
 990                                 struct sctp_association *asoc,
 991                                 union sctp_params param,
 992                                 struct sctp_ulpevent **evp)
 993 {
 994         struct sctp_stream *stream = &asoc->stream;
 995         struct sctp_strreset_resp *resp = param.v;
 996         struct sctp_transport *t;
 997         __u16 i, nums, flags = 0;
 998         struct sctp_paramhdr *req;
 999         __u32 result;
1000
1001         req = sctp_chunk_lookup_strreset_param(asoc, resp->response_seq, 0);
1002         if (!req)
1003                 return NULL;
1004
1005         result = ntohl(resp->result);
1006         if (result != SCTP_STRRESET_PERFORMED) {
1007                 /* if in progress, do nothing but retransmit */
1008                 if (result == SCTP_STRRESET_IN_PROGRESS)
1009                         return NULL;
1010                 else if (result == SCTP_STRRESET_DENIED)
1011                         flags = SCTP_STREAM_RESET_DENIED;
1012                 else
1013                         flags = SCTP_STREAM_RESET_FAILED;
1014         }
1015
1016         if (req->type == SCTP_PARAM_RESET_OUT_REQUEST) {
1017                 struct sctp_strreset_outreq *outreq;
1018                 __be16 *str_p;
1019
1020                 outreq = (struct sctp_strreset_outreq *)req;
1021                 str_p = outreq->list_of_streams;
1022                 nums = (ntohs(outreq->param_hdr.length) - sizeof(*outreq)) /
1023                        sizeof(__u16);
1024
1025                 if (result == SCTP_STRRESET_PERFORMED) {
1026                         struct sctp_stream_out *sout;
1027                         if (nums) {
1028                                 for (i = 0; i < nums; i++) {
1029                                         sout = SCTP_SO(stream, ntohs(str_p[i]));
1030                                         sout->mid = 0;
1031                                         sout->mid_uo = 0;
1032                                 }
1033                         } else {
1034                                 for (i = 0; i < stream->outcnt; i++) {
1035                                         sout = SCTP_SO(stream, i);
1036                                         sout->mid = 0;
1037                                         sout->mid_uo = 0;
1038                                 }
1039                         }
1040
1041                         flags = SCTP_STREAM_RESET_OUTGOING_SSN;
1042                 }
1043
1044                 for (i = 0; i < stream->outcnt; i++)
1045                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
1046
1047                 *evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
1048                         nums, str_p, GFP_ATOMIC);
1049         } else if (req->type == SCTP_PARAM_RESET_IN_REQUEST) {
1050                 struct sctp_strreset_inreq *inreq;
1051                 __be16 *str_p;
1052
1053                 /* if the result is performed, it's impossible for inreq */
1054                 if (result == SCTP_STRRESET_PERFORMED)
1055                         return NULL;
1056
1057                 inreq = (struct sctp_strreset_inreq *)req;
1058                 str_p = inreq->list_of_streams;
1059                 nums = (ntohs(inreq->param_hdr.length) - sizeof(*inreq)) /
1060                        sizeof(__u16);
1061
1062                 *evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
1063                         nums, str_p, GFP_ATOMIC);
1064         } else if (req->type == SCTP_PARAM_RESET_TSN_REQUEST) {
1065                 struct sctp_strreset_resptsn *resptsn;
1066                 __u32 stsn, rtsn;
1067
1068                 /* check for resptsn, as sctp_verify_reconf didn't do it*/
1069                 if (ntohs(param.p->length) != sizeof(*resptsn))
1070                         return NULL;
1071
1072                 resptsn = (struct sctp_strreset_resptsn *)resp;
1073                 stsn = ntohl(resptsn->senders_next_tsn);
1074                 rtsn = ntohl(resptsn->receivers_next_tsn);
1075
1076                 if (result == SCTP_STRRESET_PERFORMED) {
1077                         __u32 mtsn = sctp_tsnmap_get_max_tsn_seen(
1078                                                 &asoc->peer.tsn_map);
1079                         LIST_HEAD(temp);
1080
1081                         asoc->stream.si->report_ftsn(&asoc->ulpq, mtsn);
1082
1083                         sctp_tsnmap_init(&asoc->peer.tsn_map,
1084                                          SCTP_TSN_MAP_INITIAL,
1085                                          stsn, GFP_ATOMIC);
1086
1087                         /* Clean up sacked and abandoned queues only. As the
1088                          * out_chunk_list may not be empty, splice it to temp,
1089                          * then get it back after sctp_outq_free is done.
1090                          */
1091                         list_splice_init(&asoc->outqueue.out_chunk_list, &temp);
1092                         sctp_outq_free(&asoc->outqueue);
1093                         list_splice_init(&temp, &asoc->outqueue.out_chunk_list);
1094
1095                         asoc->next_tsn = rtsn;
1096                         asoc->ctsn_ack_point = asoc->next_tsn - 1;
1097                         asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
1098
1099                         for (i = 0; i < stream->outcnt; i++) {
1100                                 SCTP_SO(stream, i)->mid = 0;
1101                                 SCTP_SO(stream, i)->mid_uo = 0;
1102                         }
1103                         for (i = 0; i < stream->incnt; i++)
1104                                 SCTP_SI(stream, i)->mid = 0;
1105                 }
1106
1107                 for (i = 0; i < stream->outcnt; i++)
1108                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
1109
1110                 *evp = sctp_ulpevent_make_assoc_reset_event(asoc, flags,
1111                         stsn, rtsn, GFP_ATOMIC);
1112         } else if (req->type == SCTP_PARAM_RESET_ADD_OUT_STREAMS) {
1113                 struct sctp_strreset_addstrm *addstrm;
1114                 __u16 number;
1115
1116                 addstrm = (struct sctp_strreset_addstrm *)req;
1117                 nums = ntohs(addstrm->number_of_streams);
1118                 number = stream->outcnt - nums;
1119
1120                 if (result == SCTP_STRRESET_PERFORMED)
1121                         for (i = number; i < stream->outcnt; i++)
1122                                 SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
1123                 else
1124                         stream->outcnt = number;
1125
1126                 *evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1127                         0, nums, GFP_ATOMIC);
1128         } else if (req->type == SCTP_PARAM_RESET_ADD_IN_STREAMS) {
1129                 struct sctp_strreset_addstrm *addstrm;
1130
1131                 /* if the result is performed, it's impossible for addstrm in
1132                  * request.
1133                  */
1134                 if (result == SCTP_STRRESET_PERFORMED)
1135                         return NULL;
1136
1137                 addstrm = (struct sctp_strreset_addstrm *)req;
1138                 nums = ntohs(addstrm->number_of_streams);
1139
1140                 *evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1141                         nums, 0, GFP_ATOMIC);
1142         }
1143
1144         asoc->strreset_outstanding--;
1145         asoc->strreset_outseq++;
1146
1147         /* remove everything for this reconf request */
1148         if (!asoc->strreset_outstanding) {
1149                 t = asoc->strreset_chunk->transport;
1150                 if (del_timer(&t->reconf_timer))
1151                         sctp_transport_put(t);
1152
1153                 sctp_chunk_put(asoc->strreset_chunk);
1154                 asoc->strreset_chunk = NULL;
1155         }
1156
1157         return NULL;
1158 }