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->outcnt = outcnt;
 539
 540         asoc->strreset_outstanding = !!out + !!in;
 541
 542 out:
 543         return retval;
 544 }
 545
 546 static struct sctp_paramhdr *sctp_chunk_lookup_strreset_param(
 547                         struct sctp_association *asoc, __be32 resp_seq,
 548                         __be16 type)
 549 {
 550         struct sctp_chunk *chunk = asoc->strreset_chunk;
 551         struct sctp_reconf_chunk *hdr;
 552         union sctp_params param;
 553
 554         if (!chunk)
 555                 return NULL;
 556
 557         hdr = (struct sctp_reconf_chunk *)chunk->chunk_hdr;
 558         sctp_walk_params(param, hdr, params) {
 559                 /* sctp_strreset_tsnreq is actually the basic structure
 560                  * of all stream reconf params, so it's safe to use it
 561                  * to access request_seq.
 562                  */
 563                 struct sctp_strreset_tsnreq *req = param.v;
 564
 565                 if ((!resp_seq || req->request_seq == resp_seq) &&
 566                     (!type || type == req->param_hdr.type))
 567                         return param.v;
 568         }
 569
 570         return NULL;
 571 }
 572
 573 static void sctp_update_strreset_result(struct sctp_association *asoc,
 574                                         __u32 result)
 575 {
 576         asoc->strreset_result[1] = asoc->strreset_result[0];
 577         asoc->strreset_result[0] = result;
 578 }
 579
 580 struct sctp_chunk *sctp_process_strreset_outreq(
 581                                 struct sctp_association *asoc,
 582                                 union sctp_params param,
 583                                 struct sctp_ulpevent **evp)
 584 {
 585         struct sctp_strreset_outreq *outreq = param.v;
 586         struct sctp_stream *stream = &asoc->stream;
 587         __u32 result = SCTP_STRRESET_DENIED;
 588         __be16 *str_p = NULL;
 589         __u32 request_seq;
 590         __u16 i, nums;
 591
 592         request_seq = ntohl(outreq->request_seq);
 593
 594         if (ntohl(outreq->send_reset_at_tsn) >
 595             sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map)) {
 596                 result = SCTP_STRRESET_IN_PROGRESS;
 597                 goto err;
 598         }
 599
 600         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 601             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 602                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 603                 goto err;
 604         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 605                 i = asoc->strreset_inseq - request_seq - 1;
 606                 result = asoc->strreset_result[i];
 607                 goto err;
 608         }
 609         asoc->strreset_inseq++;
 610
 611         /* Check strreset_enable after inseq inc, as sender cannot tell
 612          * the peer doesn't enable strreset after receiving response with
 613          * result denied, as well as to keep consistent with bsd.
 614          */
 615         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
 616                 goto out;
 617
 618         nums = (ntohs(param.p->length) - sizeof(*outreq)) / sizeof(__u16);
 619         str_p = outreq->list_of_streams;
 620         for (i = 0; i < nums; i++) {
 621                 if (ntohs(str_p[i]) >= stream->incnt) {
 622                         result = SCTP_STRRESET_ERR_WRONG_SSN;
 623                         goto out;
 624                 }
 625         }
 626
 627         if (asoc->strreset_chunk) {
 628                 if (!sctp_chunk_lookup_strreset_param(
 629                                 asoc, outreq->response_seq,
 630                                 SCTP_PARAM_RESET_IN_REQUEST)) {
 631                         /* same process with outstanding isn't 0 */
 632                         result = SCTP_STRRESET_ERR_IN_PROGRESS;
 633                         goto out;
 634                 }
 635
 636                 asoc->strreset_outstanding--;
 637                 asoc->strreset_outseq++;
 638
 639                 if (!asoc->strreset_outstanding) {
 640                         struct sctp_transport *t;
 641
 642                         t = asoc->strreset_chunk->transport;
 643                         if (del_timer(&t->reconf_timer))
 644                                 sctp_transport_put(t);
 645
 646                         sctp_chunk_put(asoc->strreset_chunk);
 647                         asoc->strreset_chunk = NULL;
 648                 }
 649         }
 650
 651         if (nums)
 652                 for (i = 0; i < nums; i++)
 653                         SCTP_SI(stream, ntohs(str_p[i]))->mid = 0;
 654         else
 655                 for (i = 0; i < stream->incnt; i++)
 656                         SCTP_SI(stream, i)->mid = 0;
 657
 658         result = SCTP_STRRESET_PERFORMED;
 659
 660         *evp = sctp_ulpevent_make_stream_reset_event(asoc,
 661                 SCTP_STREAM_RESET_INCOMING_SSN, nums, str_p, GFP_ATOMIC);
 662
 663 out:
 664         sctp_update_strreset_result(asoc, result);
 665 err:
 666         return sctp_make_strreset_resp(asoc, result, request_seq);
 667 }
 668
 669 struct sctp_chunk *sctp_process_strreset_inreq(
 670                                 struct sctp_association *asoc,
 671                                 union sctp_params param,
 672                                 struct sctp_ulpevent **evp)
 673 {
 674         struct sctp_strreset_inreq *inreq = param.v;
 675         struct sctp_stream *stream = &asoc->stream;
 676         __u32 result = SCTP_STRRESET_DENIED;
 677         struct sctp_chunk *chunk = NULL;
 678         __u32 request_seq;
 679         __u16 i, nums;
 680         __be16 *str_p;
 681
 682         request_seq = ntohl(inreq->request_seq);
 683         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 684             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 685                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 686                 goto err;
 687         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 688                 i = asoc->strreset_inseq - request_seq - 1;
 689                 result = asoc->strreset_result[i];
 690                 if (result == SCTP_STRRESET_PERFORMED)
 691                         return NULL;
 692                 goto err;
 693         }
 694         asoc->strreset_inseq++;
 695
 696         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
 697                 goto out;
 698
 699         if (asoc->strreset_outstanding) {
 700                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
 701                 goto out;
 702         }
 703
 704         nums = (ntohs(param.p->length) - sizeof(*inreq)) / sizeof(__u16);
 705         str_p = inreq->list_of_streams;
 706         for (i = 0; i < nums; i++) {
 707                 if (ntohs(str_p[i]) >= stream->outcnt) {
 708                         result = SCTP_STRRESET_ERR_WRONG_SSN;
 709                         goto out;
 710                 }
 711         }
 712
 713         if (!sctp_stream_outq_is_empty(stream, nums, str_p)) {
 714                 result = SCTP_STRRESET_IN_PROGRESS;
 715                 asoc->strreset_inseq--;
 716                 goto err;
 717         }
 718
 719         chunk = sctp_make_strreset_req(asoc, nums, str_p, 1, 0);
 720         if (!chunk)
 721                 goto out;
 722
 723         if (nums)
 724                 for (i = 0; i < nums; i++)
 725                         SCTP_SO(stream, ntohs(str_p[i]))->state =
 726                                                SCTP_STREAM_CLOSED;
 727         else
 728                 for (i = 0; i < stream->outcnt; i++)
 729                         SCTP_SO(stream, i)->state = SCTP_STREAM_CLOSED;
 730
 731         asoc->strreset_chunk = chunk;
 732         asoc->strreset_outstanding = 1;
 733         sctp_chunk_hold(asoc->strreset_chunk);
 734
 735         result = SCTP_STRRESET_PERFORMED;
 736
 737 out:
 738         sctp_update_strreset_result(asoc, result);
 739 err:
 740         if (!chunk)
 741                 chunk =  sctp_make_strreset_resp(asoc, result, request_seq);
 742
 743         return chunk;
 744 }
 745
 746 struct sctp_chunk *sctp_process_strreset_tsnreq(
 747                                 struct sctp_association *asoc,
 748                                 union sctp_params param,
 749                                 struct sctp_ulpevent **evp)
 750 {
 751         __u32 init_tsn = 0, next_tsn = 0, max_tsn_seen;
 752         struct sctp_strreset_tsnreq *tsnreq = param.v;
 753         struct sctp_stream *stream = &asoc->stream;
 754         __u32 result = SCTP_STRRESET_DENIED;
 755         __u32 request_seq;
 756         __u16 i;
 757
 758         request_seq = ntohl(tsnreq->request_seq);
 759         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 760             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 761                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 762                 goto err;
 763         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 764                 i = asoc->strreset_inseq - request_seq - 1;
 765                 result = asoc->strreset_result[i];
 766                 if (result == SCTP_STRRESET_PERFORMED) {
 767                         next_tsn = asoc->ctsn_ack_point + 1;
 768                         init_tsn =
 769                                 sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + 1;
 770                 }
 771                 goto err;
 772         }
 773
 774         if (!sctp_outq_is_empty(&asoc->outqueue)) {
 775                 result = SCTP_STRRESET_IN_PROGRESS;
 776                 goto err;
 777         }
 778
 779         asoc->strreset_inseq++;
 780
 781         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
 782                 goto out;
 783
 784         if (asoc->strreset_outstanding) {
 785                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
 786                 goto out;
 787         }
 788
 789         /* G4: The same processing as though a FWD-TSN chunk (as defined in
 790          *     [RFC3758]) with all streams affected and a new cumulative TSN
 791          *     ACK of the Receiver's Next TSN minus 1 were received MUST be
 792          *     performed.
 793          */
 794         max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
 795         asoc->stream.si->report_ftsn(&asoc->ulpq, max_tsn_seen);
 796
 797         /* G1: Compute an appropriate value for the Receiver's Next TSN -- the
 798          *     TSN that the peer should use to send the next DATA chunk.  The
 799          *     value SHOULD be the smallest TSN not acknowledged by the
 800          *     receiver of the request plus 2^31.
 801          */
 802         init_tsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + (1 << 31);
 803         sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
 804                          init_tsn, GFP_ATOMIC);
 805
 806         /* G3: The same processing as though a SACK chunk with no gap report
 807          *     and a cumulative TSN ACK of the Sender's Next TSN minus 1 were
 808          *     received MUST be performed.
 809          */
 810         sctp_outq_free(&asoc->outqueue);
 811
 812         /* G2: Compute an appropriate value for the local endpoint's next TSN,
 813          *     i.e., the next TSN assigned by the receiver of the SSN/TSN reset
 814          *     chunk.  The value SHOULD be the highest TSN sent by the receiver
 815          *     of the request plus 1.
 816          */
 817         next_tsn = asoc->next_tsn;
 818         asoc->ctsn_ack_point = next_tsn - 1;
 819         asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
 820
 821         /* G5:  The next expected and outgoing SSNs MUST be reset to 0 for all
 822          *      incoming and outgoing streams.
 823          */
 824         for (i = 0; i < stream->outcnt; i++) {
 825                 SCTP_SO(stream, i)->mid = 0;
 826                 SCTP_SO(stream, i)->mid_uo = 0;
 827         }
 828         for (i = 0; i < stream->incnt; i++)
 829                 SCTP_SI(stream, i)->mid = 0;
 830
 831         result = SCTP_STRRESET_PERFORMED;
 832
 833         *evp = sctp_ulpevent_make_assoc_reset_event(asoc, 0, init_tsn,
 834                                                     next_tsn, GFP_ATOMIC);
 835
 836 out:
 837         sctp_update_strreset_result(asoc, result);
 838 err:
 839         return sctp_make_strreset_tsnresp(asoc, result, request_seq,
 840                                           next_tsn, init_tsn);
 841 }
 842
 843 struct sctp_chunk *sctp_process_strreset_addstrm_out(
 844                                 struct sctp_association *asoc,
 845                                 union sctp_params param,
 846                                 struct sctp_ulpevent **evp)
 847 {
 848         struct sctp_strreset_addstrm *addstrm = param.v;
 849         struct sctp_stream *stream = &asoc->stream;
 850         __u32 result = SCTP_STRRESET_DENIED;
 851         __u32 request_seq, incnt;
 852         __u16 in, i;
 853
 854         request_seq = ntohl(addstrm->request_seq);
 855         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 856             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 857                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 858                 goto err;
 859         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 860                 i = asoc->strreset_inseq - request_seq - 1;
 861                 result = asoc->strreset_result[i];
 862                 goto err;
 863         }
 864         asoc->strreset_inseq++;
 865
 866         if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
 867                 goto out;
 868
 869         in = ntohs(addstrm->number_of_streams);
 870         incnt = stream->incnt + in;
 871         if (!in || incnt > SCTP_MAX_STREAM)
 872                 goto out;
 873
 874         if (sctp_stream_alloc_in(stream, incnt, GFP_ATOMIC))
 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         stream->incnt = incnt;
 901
 902         result = SCTP_STRRESET_PERFORMED;
 903
 904         *evp = sctp_ulpevent_make_stream_change_event(asoc,
 905                 0, ntohs(addstrm->number_of_streams), 0, GFP_ATOMIC);
 906
 907 out:
 908         sctp_update_strreset_result(asoc, result);
 909 err:
 910         return sctp_make_strreset_resp(asoc, result, request_seq);
 911 }
 912
 913 struct sctp_chunk *sctp_process_strreset_addstrm_in(
 914                                 struct sctp_association *asoc,
 915                                 union sctp_params param,
 916                                 struct sctp_ulpevent **evp)
 917 {
 918         struct sctp_strreset_addstrm *addstrm = param.v;
 919         struct sctp_stream *stream = &asoc->stream;
 920         __u32 result = SCTP_STRRESET_DENIED;
 921         struct sctp_chunk *chunk = NULL;
 922         __u32 request_seq, outcnt;
 923         __u16 out, i;
 924         int ret;
 925
 926         request_seq = ntohl(addstrm->request_seq);
 927         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 928             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 929                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 930                 goto err;
 931         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 932                 i = asoc->strreset_inseq - request_seq - 1;
 933                 result = asoc->strreset_result[i];
 934                 if (result == SCTP_STRRESET_PERFORMED)
 935                         return NULL;
 936                 goto err;
 937         }
 938         asoc->strreset_inseq++;
 939
 940         if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
 941                 goto out;
 942
 943         if (asoc->strreset_outstanding) {
 944                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
 945                 goto out;
 946         }
 947
 948         out = ntohs(addstrm->number_of_streams);
 949         outcnt = stream->outcnt + out;
 950         if (!out || outcnt > SCTP_MAX_STREAM)
 951                 goto out;
 952
 953         ret = sctp_stream_alloc_out(stream, outcnt, GFP_ATOMIC);
 954         if (ret)
 955                 goto out;
 956
 957         chunk = sctp_make_strreset_addstrm(asoc, out, 0);
 958         if (!chunk)
 959                 goto out;
 960
 961         asoc->strreset_chunk = chunk;
 962         asoc->strreset_outstanding = 1;
 963         sctp_chunk_hold(asoc->strreset_chunk);
 964
 965         stream->outcnt = outcnt;
 966
 967         result = SCTP_STRRESET_PERFORMED;
 968
 969 out:
 970         sctp_update_strreset_result(asoc, result);
 971 err:
 972         if (!chunk)
 973                 chunk = sctp_make_strreset_resp(asoc, result, request_seq);
 974
 975         return chunk;
 976 }
 977
 978 struct sctp_chunk *sctp_process_strreset_resp(
 979                                 struct sctp_association *asoc,
 980                                 union sctp_params param,
 981                                 struct sctp_ulpevent **evp)
 982 {
 983         struct sctp_stream *stream = &asoc->stream;
 984         struct sctp_strreset_resp *resp = param.v;
 985         struct sctp_transport *t;
 986         __u16 i, nums, flags = 0;
 987         struct sctp_paramhdr *req;
 988         __u32 result;
 989
 990         req = sctp_chunk_lookup_strreset_param(asoc, resp->response_seq, 0);
 991         if (!req)
 992                 return NULL;
 993
 994         result = ntohl(resp->result);
 995         if (result != SCTP_STRRESET_PERFORMED) {
 996                 /* if in progress, do nothing but retransmit */
 997                 if (result == SCTP_STRRESET_IN_PROGRESS)
 998                         return NULL;
 999                 else if (result == SCTP_STRRESET_DENIED)
1000                         flags = SCTP_STREAM_RESET_DENIED;
1001                 else
1002                         flags = SCTP_STREAM_RESET_FAILED;
1003         }
1004
1005         if (req->type == SCTP_PARAM_RESET_OUT_REQUEST) {
1006                 struct sctp_strreset_outreq *outreq;
1007                 __be16 *str_p;
1008
1009                 outreq = (struct sctp_strreset_outreq *)req;
1010                 str_p = outreq->list_of_streams;
1011                 nums = (ntohs(outreq->param_hdr.length) - sizeof(*outreq)) /
1012                        sizeof(__u16);
1013
1014                 if (result == SCTP_STRRESET_PERFORMED) {
1015                         struct sctp_stream_out *sout;
1016                         if (nums) {
1017                                 for (i = 0; i < nums; i++) {
1018                                         sout = SCTP_SO(stream, ntohs(str_p[i]));
1019                                         sout->mid = 0;
1020                                         sout->mid_uo = 0;
1021                                 }
1022                         } else {
1023                                 for (i = 0; i < stream->outcnt; i++) {
1024                                         sout = SCTP_SO(stream, i);
1025                                         sout->mid = 0;
1026                                         sout->mid_uo = 0;
1027                                 }
1028                         }
1029                 }
1030
1031                 flags |= SCTP_STREAM_RESET_OUTGOING_SSN;
1032
1033                 for (i = 0; i < stream->outcnt; i++)
1034                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
1035
1036                 *evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
1037                         nums, str_p, GFP_ATOMIC);
1038         } else if (req->type == SCTP_PARAM_RESET_IN_REQUEST) {
1039                 struct sctp_strreset_inreq *inreq;
1040                 __be16 *str_p;
1041
1042                 /* if the result is performed, it's impossible for inreq */
1043                 if (result == SCTP_STRRESET_PERFORMED)
1044                         return NULL;
1045
1046                 inreq = (struct sctp_strreset_inreq *)req;
1047                 str_p = inreq->list_of_streams;
1048                 nums = (ntohs(inreq->param_hdr.length) - sizeof(*inreq)) /
1049                        sizeof(__u16);
1050
1051                 flags |= SCTP_STREAM_RESET_INCOMING_SSN;
1052
1053                 *evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
1054                         nums, str_p, GFP_ATOMIC);
1055         } else if (req->type == SCTP_PARAM_RESET_TSN_REQUEST) {
1056                 struct sctp_strreset_resptsn *resptsn;
1057                 __u32 stsn, rtsn;
1058
1059                 /* check for resptsn, as sctp_verify_reconf didn't do it*/
1060                 if (ntohs(param.p->length) != sizeof(*resptsn))
1061                         return NULL;
1062
1063                 resptsn = (struct sctp_strreset_resptsn *)resp;
1064                 stsn = ntohl(resptsn->senders_next_tsn);
1065                 rtsn = ntohl(resptsn->receivers_next_tsn);
1066
1067                 if (result == SCTP_STRRESET_PERFORMED) {
1068                         __u32 mtsn = sctp_tsnmap_get_max_tsn_seen(
1069                                                 &asoc->peer.tsn_map);
1070                         LIST_HEAD(temp);
1071
1072                         asoc->stream.si->report_ftsn(&asoc->ulpq, mtsn);
1073
1074                         sctp_tsnmap_init(&asoc->peer.tsn_map,
1075                                          SCTP_TSN_MAP_INITIAL,
1076                                          stsn, GFP_ATOMIC);
1077
1078                         /* Clean up sacked and abandoned queues only. As the
1079                          * out_chunk_list may not be empty, splice it to temp,
1080                          * then get it back after sctp_outq_free is done.
1081                          */
1082                         list_splice_init(&asoc->outqueue.out_chunk_list, &temp);
1083                         sctp_outq_free(&asoc->outqueue);
1084                         list_splice_init(&temp, &asoc->outqueue.out_chunk_list);
1085
1086                         asoc->next_tsn = rtsn;
1087                         asoc->ctsn_ack_point = asoc->next_tsn - 1;
1088                         asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
1089
1090                         for (i = 0; i < stream->outcnt; i++) {
1091                                 SCTP_SO(stream, i)->mid = 0;
1092                                 SCTP_SO(stream, i)->mid_uo = 0;
1093                         }
1094                         for (i = 0; i < stream->incnt; i++)
1095                                 SCTP_SI(stream, i)->mid = 0;
1096                 }
1097
1098                 for (i = 0; i < stream->outcnt; i++)
1099                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
1100
1101                 *evp = sctp_ulpevent_make_assoc_reset_event(asoc, flags,
1102                         stsn, rtsn, GFP_ATOMIC);
1103         } else if (req->type == SCTP_PARAM_RESET_ADD_OUT_STREAMS) {
1104                 struct sctp_strreset_addstrm *addstrm;
1105                 __u16 number;
1106
1107                 addstrm = (struct sctp_strreset_addstrm *)req;
1108                 nums = ntohs(addstrm->number_of_streams);
1109                 number = stream->outcnt - nums;
1110
1111                 if (result == SCTP_STRRESET_PERFORMED)
1112                         for (i = number; i < stream->outcnt; i++)
1113                                 SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
1114                 else
1115                         stream->outcnt = number;
1116
1117                 *evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1118                         0, nums, GFP_ATOMIC);
1119         } else if (req->type == SCTP_PARAM_RESET_ADD_IN_STREAMS) {
1120                 struct sctp_strreset_addstrm *addstrm;
1121
1122                 /* if the result is performed, it's impossible for addstrm in
1123                  * request.
1124                  */
1125                 if (result == SCTP_STRRESET_PERFORMED)
1126                         return NULL;
1127
1128                 addstrm = (struct sctp_strreset_addstrm *)req;
1129                 nums = ntohs(addstrm->number_of_streams);
1130
1131                 *evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1132                         nums, 0, GFP_ATOMIC);
1133         }
1134
1135         asoc->strreset_outstanding--;
1136         asoc->strreset_outseq++;
1137
1138         /* remove everything for this reconf request */
1139         if (!asoc->strreset_outstanding) {
1140                 t = asoc->strreset_chunk->transport;
1141                 if (del_timer(&t->reconf_timer))
1142                         sctp_transport_put(t);
1143
1144                 sctp_chunk_put(asoc->strreset_chunk);
1145                 asoc->strreset_chunk = NULL;
1146         }
1147
1148         return NULL;
1149 }