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 static size_t fa_index(struct flex_array *fa, void *elem, size_t count)
  88 {
  89         size_t index = 0;
  90
  91         while (count--) {
  92                 if (elem == flex_array_get(fa, index))
  93                         break;
  94                 index++;
  95         }
  96
  97         return index;
  98 }
  99
 100 /* Migrates chunks from stream queues to new stream queues if needed,
 101  * but not across associations. Also, removes those chunks to streams
 102  * higher than the new max.
 103  */
 104 static void sctp_stream_outq_migrate(struct sctp_stream *stream,
 105                                      struct sctp_stream *new, __u16 outcnt)
 106 {
 107         struct sctp_association *asoc;
 108         struct sctp_chunk *ch, *temp;
 109         struct sctp_outq *outq;
 110         int i;
 111
 112         asoc = container_of(stream, struct sctp_association, stream);
 113         outq = &asoc->outqueue;
 114
 115         list_for_each_entry_safe(ch, temp, &outq->out_chunk_list, list) {
 116                 __u16 sid = sctp_chunk_stream_no(ch);
 117
 118                 if (sid < outcnt)
 119                         continue;
 120
 121                 sctp_sched_dequeue_common(outq, ch);
 122                 /* No need to call dequeue_done here because
 123                  * the chunks are not scheduled by now.
 124                  */
 125
 126                 /* Mark as failed send. */
 127                 sctp_chunk_fail(ch, (__force __u32)SCTP_ERROR_INV_STRM);
 128                 if (asoc->peer.prsctp_capable &&
 129                     SCTP_PR_PRIO_ENABLED(ch->sinfo.sinfo_flags))
 130                         asoc->sent_cnt_removable--;
 131
 132                 sctp_chunk_free(ch);
 133         }
 134
 135         if (new) {
 136                 /* Here we actually move the old ext stuff into the new
 137                  * buffer, because we want to keep it. Then
 138                  * sctp_stream_update will swap ->out pointers.
 139                  */
 140                 for (i = 0; i < outcnt; i++) {
 141                         kfree(SCTP_SO(new, i)->ext);
 142                         SCTP_SO(new, i)->ext = SCTP_SO(stream, i)->ext;
 143                         SCTP_SO(stream, i)->ext = NULL;
 144                 }
 145         }
 146
 147         for (i = outcnt; i < stream->outcnt; i++)
 148                 kfree(SCTP_SO(stream, i)->ext);
 149 }
 150
 151 static int sctp_stream_alloc_out(struct sctp_stream *stream, __u16 outcnt,
 152                                  gfp_t gfp)
 153 {
 154         struct flex_array *out;
 155         size_t elem_size = sizeof(struct sctp_stream_out);
 156
 157         out = fa_alloc(elem_size, outcnt, gfp);
 158         if (!out)
 159                 return -ENOMEM;
 160
 161         if (stream->out) {
 162                 fa_copy(out, stream->out, 0, min(outcnt, stream->outcnt));
 163                 if (stream->out_curr) {
 164                         size_t index = fa_index(stream->out, stream->out_curr,
 165                                                 stream->outcnt);
 166
 167                         BUG_ON(index == stream->outcnt);
 168                         stream->out_curr = flex_array_get(out, index);
 169                 }
 170                 fa_free(stream->out);
 171         }
 172
 173         if (outcnt > stream->outcnt)
 174                 fa_zero(out, stream->outcnt, (outcnt - stream->outcnt));
 175
 176         stream->out = out;
 177
 178         return 0;
 179 }
 180
 181 static int sctp_stream_alloc_in(struct sctp_stream *stream, __u16 incnt,
 182                                 gfp_t gfp)
 183 {
 184         struct flex_array *in;
 185         size_t elem_size = sizeof(struct sctp_stream_in);
 186
 187         in = fa_alloc(elem_size, incnt, gfp);
 188         if (!in)
 189                 return -ENOMEM;
 190
 191         if (stream->in) {
 192                 fa_copy(in, stream->in, 0, min(incnt, stream->incnt));
 193                 fa_free(stream->in);
 194         }
 195
 196         if (incnt > stream->incnt)
 197                 fa_zero(in, stream->incnt, (incnt - stream->incnt));
 198
 199         stream->in = in;
 200
 201         return 0;
 202 }
 203
 204 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt,
 205                      gfp_t gfp)
 206 {
 207         struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
 208         int i, ret = 0;
 209
 210         gfp |= __GFP_NOWARN;
 211
 212         /* Initial stream->out size may be very big, so free it and alloc
 213          * a new one with new outcnt to save memory if needed.
 214          */
 215         if (outcnt == stream->outcnt)
 216                 goto in;
 217
 218         /* Filter out chunks queued on streams that won't exist anymore */
 219         sched->unsched_all(stream);
 220         sctp_stream_outq_migrate(stream, NULL, outcnt);
 221         sched->sched_all(stream);
 222
 223         ret = sctp_stream_alloc_out(stream, outcnt, gfp);
 224         if (ret)
 225                 goto out;
 226
 227         stream->outcnt = outcnt;
 228         for (i = 0; i < stream->outcnt; i++)
 229                 SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
 230
 231         sched->init(stream);
 232
 233 in:
 234         sctp_stream_interleave_init(stream);
 235         if (!incnt)
 236                 goto out;
 237
 238         ret = sctp_stream_alloc_in(stream, incnt, gfp);
 239         if (ret) {
 240                 sched->free(stream);
 241                 fa_free(stream->out);
 242                 stream->out = NULL;
 243                 stream->outcnt = 0;
 244                 goto out;
 245         }
 246
 247         stream->incnt = incnt;
 248
 249 out:
 250         return ret;
 251 }
 252
 253 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid)
 254 {
 255         struct sctp_stream_out_ext *soute;
 256
 257         soute = kzalloc(sizeof(*soute), GFP_KERNEL);
 258         if (!soute)
 259                 return -ENOMEM;
 260         SCTP_SO(stream, sid)->ext = soute;
 261
 262         return sctp_sched_init_sid(stream, sid, GFP_KERNEL);
 263 }
 264
 265 void sctp_stream_free(struct sctp_stream *stream)
 266 {
 267         struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
 268         int i;
 269
 270         sched->free(stream);
 271         for (i = 0; i < stream->outcnt; i++)
 272                 kfree(SCTP_SO(stream, i)->ext);
 273         fa_free(stream->out);
 274         fa_free(stream->in);
 275 }
 276
 277 void sctp_stream_clear(struct sctp_stream *stream)
 278 {
 279         int i;
 280
 281         for (i = 0; i < stream->outcnt; i++) {
 282                 SCTP_SO(stream, i)->mid = 0;
 283                 SCTP_SO(stream, i)->mid_uo = 0;
 284         }
 285
 286         for (i = 0; i < stream->incnt; i++)
 287                 SCTP_SI(stream, i)->mid = 0;
 288 }
 289
 290 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new)
 291 {
 292         struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
 293
 294         sched->unsched_all(stream);
 295         sctp_stream_outq_migrate(stream, new, new->outcnt);
 296         sctp_stream_free(stream);
 297
 298         stream->out = new->out;
 299         stream->in  = new->in;
 300         stream->outcnt = new->outcnt;
 301         stream->incnt  = new->incnt;
 302
 303         sched->sched_all(stream);
 304
 305         new->out = NULL;
 306         new->in  = NULL;
 307         new->outcnt = 0;
 308         new->incnt  = 0;
 309 }
 310
 311 static int sctp_send_reconf(struct sctp_association *asoc,
 312                             struct sctp_chunk *chunk)
 313 {
 314         struct net *net = sock_net(asoc->base.sk);
 315         int retval = 0;
 316
 317         retval = sctp_primitive_RECONF(net, asoc, chunk);
 318         if (retval)
 319                 sctp_chunk_free(chunk);
 320
 321         return retval;
 322 }
 323
 324 static bool sctp_stream_outq_is_empty(struct sctp_stream *stream,
 325                                       __u16 str_nums, __be16 *str_list)
 326 {
 327         struct sctp_association *asoc;
 328         __u16 i;
 329
 330         asoc = container_of(stream, struct sctp_association, stream);
 331         if (!asoc->outqueue.out_qlen)
 332                 return true;
 333
 334         if (!str_nums)
 335                 return false;
 336
 337         for (i = 0; i < str_nums; i++) {
 338                 __u16 sid = ntohs(str_list[i]);
 339
 340                 if (SCTP_SO(stream, sid)->ext &&
 341                     !list_empty(&SCTP_SO(stream, sid)->ext->outq))
 342                         return false;
 343         }
 344
 345         return true;
 346 }
 347
 348 int sctp_send_reset_streams(struct sctp_association *asoc,
 349                             struct sctp_reset_streams *params)
 350 {
 351         struct sctp_stream *stream = &asoc->stream;
 352         __u16 i, str_nums, *str_list;
 353         struct sctp_chunk *chunk;
 354         int retval = -EINVAL;
 355         __be16 *nstr_list;
 356         bool out, in;
 357
 358         if (!asoc->peer.reconf_capable ||
 359             !(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ)) {
 360                 retval = -ENOPROTOOPT;
 361                 goto out;
 362         }
 363
 364         if (asoc->strreset_outstanding) {
 365                 retval = -EINPROGRESS;
 366                 goto out;
 367         }
 368
 369         out = params->srs_flags & SCTP_STREAM_RESET_OUTGOING;
 370         in  = params->srs_flags & SCTP_STREAM_RESET_INCOMING;
 371         if (!out && !in)
 372                 goto out;
 373
 374         str_nums = params->srs_number_streams;
 375         str_list = params->srs_stream_list;
 376         if (str_nums) {
 377                 int param_len = 0;
 378
 379                 if (out) {
 380                         for (i = 0; i < str_nums; i++)
 381                                 if (str_list[i] >= stream->outcnt)
 382                                         goto out;
 383
 384                         param_len = str_nums * sizeof(__u16) +
 385                                     sizeof(struct sctp_strreset_outreq);
 386                 }
 387
 388                 if (in) {
 389                         for (i = 0; i < str_nums; i++)
 390                                 if (str_list[i] >= stream->incnt)
 391                                         goto out;
 392
 393                         param_len += str_nums * sizeof(__u16) +
 394                                      sizeof(struct sctp_strreset_inreq);
 395                 }
 396
 397                 if (param_len > SCTP_MAX_CHUNK_LEN -
 398                                 sizeof(struct sctp_reconf_chunk))
 399                         goto out;
 400         }
 401
 402         nstr_list = kcalloc(str_nums, sizeof(__be16), GFP_KERNEL);
 403         if (!nstr_list) {
 404                 retval = -ENOMEM;
 405                 goto out;
 406         }
 407
 408         for (i = 0; i < str_nums; i++)
 409                 nstr_list[i] = htons(str_list[i]);
 410
 411         if (out && !sctp_stream_outq_is_empty(stream, str_nums, nstr_list)) {
 412                 retval = -EAGAIN;
 413                 goto out;
 414         }
 415
 416         chunk = sctp_make_strreset_req(asoc, str_nums, nstr_list, out, in);
 417
 418         kfree(nstr_list);
 419
 420         if (!chunk) {
 421                 retval = -ENOMEM;
 422                 goto out;
 423         }
 424
 425         if (out) {
 426                 if (str_nums)
 427                         for (i = 0; i < str_nums; i++)
 428                                 SCTP_SO(stream, str_list[i])->state =
 429                                                        SCTP_STREAM_CLOSED;
 430                 else
 431                         for (i = 0; i < stream->outcnt; i++)
 432                                 SCTP_SO(stream, i)->state = SCTP_STREAM_CLOSED;
 433         }
 434
 435         asoc->strreset_chunk = chunk;
 436         sctp_chunk_hold(asoc->strreset_chunk);
 437
 438         retval = sctp_send_reconf(asoc, chunk);
 439         if (retval) {
 440                 sctp_chunk_put(asoc->strreset_chunk);
 441                 asoc->strreset_chunk = NULL;
 442                 if (!out)
 443                         goto out;
 444
 445                 if (str_nums)
 446                         for (i = 0; i < str_nums; i++)
 447                                 SCTP_SO(stream, str_list[i])->state =
 448                                                        SCTP_STREAM_OPEN;
 449                 else
 450                         for (i = 0; i < stream->outcnt; i++)
 451                                 SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
 452
 453                 goto out;
 454         }
 455
 456         asoc->strreset_outstanding = out + in;
 457
 458 out:
 459         return retval;
 460 }
 461
 462 int sctp_send_reset_assoc(struct sctp_association *asoc)
 463 {
 464         struct sctp_stream *stream = &asoc->stream;
 465         struct sctp_chunk *chunk = NULL;
 466         int retval;
 467         __u16 i;
 468
 469         if (!asoc->peer.reconf_capable ||
 470             !(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
 471                 return -ENOPROTOOPT;
 472
 473         if (asoc->strreset_outstanding)
 474                 return -EINPROGRESS;
 475
 476         if (!sctp_outq_is_empty(&asoc->outqueue))
 477                 return -EAGAIN;
 478
 479         chunk = sctp_make_strreset_tsnreq(asoc);
 480         if (!chunk)
 481                 return -ENOMEM;
 482
 483         /* Block further xmit of data until this request is completed */
 484         for (i = 0; i < stream->outcnt; i++)
 485                 SCTP_SO(stream, i)->state = SCTP_STREAM_CLOSED;
 486
 487         asoc->strreset_chunk = chunk;
 488         sctp_chunk_hold(asoc->strreset_chunk);
 489
 490         retval = sctp_send_reconf(asoc, chunk);
 491         if (retval) {
 492                 sctp_chunk_put(asoc->strreset_chunk);
 493                 asoc->strreset_chunk = NULL;
 494
 495                 for (i = 0; i < stream->outcnt; i++)
 496                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
 497
 498                 return retval;
 499         }
 500
 501         asoc->strreset_outstanding = 1;
 502
 503         return 0;
 504 }
 505
 506 int sctp_send_add_streams(struct sctp_association *asoc,
 507                           struct sctp_add_streams *params)
 508 {
 509         struct sctp_stream *stream = &asoc->stream;
 510         struct sctp_chunk *chunk = NULL;
 511         int retval;
 512         __u32 outcnt, incnt;
 513         __u16 out, in;
 514
 515         if (!asoc->peer.reconf_capable ||
 516             !(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ)) {
 517                 retval = -ENOPROTOOPT;
 518                 goto out;
 519         }
 520
 521         if (asoc->strreset_outstanding) {
 522                 retval = -EINPROGRESS;
 523                 goto out;
 524         }
 525
 526         out = params->sas_outstrms;
 527         in  = params->sas_instrms;
 528         outcnt = stream->outcnt + out;
 529         incnt = stream->incnt + in;
 530         if (outcnt > SCTP_MAX_STREAM || incnt > SCTP_MAX_STREAM ||
 531             (!out && !in)) {
 532                 retval = -EINVAL;
 533                 goto out;
 534         }
 535
 536         if (out) {
 537                 retval = sctp_stream_alloc_out(stream, outcnt, GFP_KERNEL);
 538                 if (retval)
 539                         goto out;
 540         }
 541
 542         chunk = sctp_make_strreset_addstrm(asoc, out, in);
 543         if (!chunk) {
 544                 retval = -ENOMEM;
 545                 goto out;
 546         }
 547
 548         asoc->strreset_chunk = chunk;
 549         sctp_chunk_hold(asoc->strreset_chunk);
 550
 551         retval = sctp_send_reconf(asoc, chunk);
 552         if (retval) {
 553                 sctp_chunk_put(asoc->strreset_chunk);
 554                 asoc->strreset_chunk = NULL;
 555                 goto out;
 556         }
 557
 558         stream->outcnt = outcnt;
 559
 560         asoc->strreset_outstanding = !!out + !!in;
 561
 562 out:
 563         return retval;
 564 }
 565
 566 static struct sctp_paramhdr *sctp_chunk_lookup_strreset_param(
 567                         struct sctp_association *asoc, __be32 resp_seq,
 568                         __be16 type)
 569 {
 570         struct sctp_chunk *chunk = asoc->strreset_chunk;
 571         struct sctp_reconf_chunk *hdr;
 572         union sctp_params param;
 573
 574         if (!chunk)
 575                 return NULL;
 576
 577         hdr = (struct sctp_reconf_chunk *)chunk->chunk_hdr;
 578         sctp_walk_params(param, hdr, params) {
 579                 /* sctp_strreset_tsnreq is actually the basic structure
 580                  * of all stream reconf params, so it's safe to use it
 581                  * to access request_seq.
 582                  */
 583                 struct sctp_strreset_tsnreq *req = param.v;
 584
 585                 if ((!resp_seq || req->request_seq == resp_seq) &&
 586                     (!type || type == req->param_hdr.type))
 587                         return param.v;
 588         }
 589
 590         return NULL;
 591 }
 592
 593 static void sctp_update_strreset_result(struct sctp_association *asoc,
 594                                         __u32 result)
 595 {
 596         asoc->strreset_result[1] = asoc->strreset_result[0];
 597         asoc->strreset_result[0] = result;
 598 }
 599
 600 struct sctp_chunk *sctp_process_strreset_outreq(
 601                                 struct sctp_association *asoc,
 602                                 union sctp_params param,
 603                                 struct sctp_ulpevent **evp)
 604 {
 605         struct sctp_strreset_outreq *outreq = param.v;
 606         struct sctp_stream *stream = &asoc->stream;
 607         __u32 result = SCTP_STRRESET_DENIED;
 608         __be16 *str_p = NULL;
 609         __u32 request_seq;
 610         __u16 i, nums;
 611
 612         request_seq = ntohl(outreq->request_seq);
 613
 614         if (ntohl(outreq->send_reset_at_tsn) >
 615             sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map)) {
 616                 result = SCTP_STRRESET_IN_PROGRESS;
 617                 goto err;
 618         }
 619
 620         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 621             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 622                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 623                 goto err;
 624         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 625                 i = asoc->strreset_inseq - request_seq - 1;
 626                 result = asoc->strreset_result[i];
 627                 goto err;
 628         }
 629         asoc->strreset_inseq++;
 630
 631         /* Check strreset_enable after inseq inc, as sender cannot tell
 632          * the peer doesn't enable strreset after receiving response with
 633          * result denied, as well as to keep consistent with bsd.
 634          */
 635         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
 636                 goto out;
 637
 638         nums = (ntohs(param.p->length) - sizeof(*outreq)) / sizeof(__u16);
 639         str_p = outreq->list_of_streams;
 640         for (i = 0; i < nums; i++) {
 641                 if (ntohs(str_p[i]) >= stream->incnt) {
 642                         result = SCTP_STRRESET_ERR_WRONG_SSN;
 643                         goto out;
 644                 }
 645         }
 646
 647         if (asoc->strreset_chunk) {
 648                 if (!sctp_chunk_lookup_strreset_param(
 649                                 asoc, outreq->response_seq,
 650                                 SCTP_PARAM_RESET_IN_REQUEST)) {
 651                         /* same process with outstanding isn't 0 */
 652                         result = SCTP_STRRESET_ERR_IN_PROGRESS;
 653                         goto out;
 654                 }
 655
 656                 asoc->strreset_outstanding--;
 657                 asoc->strreset_outseq++;
 658
 659                 if (!asoc->strreset_outstanding) {
 660                         struct sctp_transport *t;
 661
 662                         t = asoc->strreset_chunk->transport;
 663                         if (del_timer(&t->reconf_timer))
 664                                 sctp_transport_put(t);
 665
 666                         sctp_chunk_put(asoc->strreset_chunk);
 667                         asoc->strreset_chunk = NULL;
 668                 }
 669         }
 670
 671         if (nums)
 672                 for (i = 0; i < nums; i++)
 673                         SCTP_SI(stream, ntohs(str_p[i]))->mid = 0;
 674         else
 675                 for (i = 0; i < stream->incnt; i++)
 676                         SCTP_SI(stream, i)->mid = 0;
 677
 678         result = SCTP_STRRESET_PERFORMED;
 679
 680         *evp = sctp_ulpevent_make_stream_reset_event(asoc,
 681                 SCTP_STREAM_RESET_INCOMING_SSN, nums, str_p, GFP_ATOMIC);
 682
 683 out:
 684         sctp_update_strreset_result(asoc, result);
 685 err:
 686         return sctp_make_strreset_resp(asoc, result, request_seq);
 687 }
 688
 689 struct sctp_chunk *sctp_process_strreset_inreq(
 690                                 struct sctp_association *asoc,
 691                                 union sctp_params param,
 692                                 struct sctp_ulpevent **evp)
 693 {
 694         struct sctp_strreset_inreq *inreq = param.v;
 695         struct sctp_stream *stream = &asoc->stream;
 696         __u32 result = SCTP_STRRESET_DENIED;
 697         struct sctp_chunk *chunk = NULL;
 698         __u32 request_seq;
 699         __u16 i, nums;
 700         __be16 *str_p;
 701
 702         request_seq = ntohl(inreq->request_seq);
 703         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 704             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 705                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 706                 goto err;
 707         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 708                 i = asoc->strreset_inseq - request_seq - 1;
 709                 result = asoc->strreset_result[i];
 710                 if (result == SCTP_STRRESET_PERFORMED)
 711                         return NULL;
 712                 goto err;
 713         }
 714         asoc->strreset_inseq++;
 715
 716         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
 717                 goto out;
 718
 719         if (asoc->strreset_outstanding) {
 720                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
 721                 goto out;
 722         }
 723
 724         nums = (ntohs(param.p->length) - sizeof(*inreq)) / sizeof(__u16);
 725         str_p = inreq->list_of_streams;
 726         for (i = 0; i < nums; i++) {
 727                 if (ntohs(str_p[i]) >= stream->outcnt) {
 728                         result = SCTP_STRRESET_ERR_WRONG_SSN;
 729                         goto out;
 730                 }
 731         }
 732
 733         if (!sctp_stream_outq_is_empty(stream, nums, str_p)) {
 734                 result = SCTP_STRRESET_IN_PROGRESS;
 735                 asoc->strreset_inseq--;
 736                 goto err;
 737         }
 738
 739         chunk = sctp_make_strreset_req(asoc, nums, str_p, 1, 0);
 740         if (!chunk)
 741                 goto out;
 742
 743         if (nums)
 744                 for (i = 0; i < nums; i++)
 745                         SCTP_SO(stream, ntohs(str_p[i]))->state =
 746                                                SCTP_STREAM_CLOSED;
 747         else
 748                 for (i = 0; i < stream->outcnt; i++)
 749                         SCTP_SO(stream, i)->state = SCTP_STREAM_CLOSED;
 750
 751         asoc->strreset_chunk = chunk;
 752         asoc->strreset_outstanding = 1;
 753         sctp_chunk_hold(asoc->strreset_chunk);
 754
 755         result = SCTP_STRRESET_PERFORMED;
 756
 757 out:
 758         sctp_update_strreset_result(asoc, result);
 759 err:
 760         if (!chunk)
 761                 chunk =  sctp_make_strreset_resp(asoc, result, request_seq);
 762
 763         return chunk;
 764 }
 765
 766 struct sctp_chunk *sctp_process_strreset_tsnreq(
 767                                 struct sctp_association *asoc,
 768                                 union sctp_params param,
 769                                 struct sctp_ulpevent **evp)
 770 {
 771         __u32 init_tsn = 0, next_tsn = 0, max_tsn_seen;
 772         struct sctp_strreset_tsnreq *tsnreq = param.v;
 773         struct sctp_stream *stream = &asoc->stream;
 774         __u32 result = SCTP_STRRESET_DENIED;
 775         __u32 request_seq;
 776         __u16 i;
 777
 778         request_seq = ntohl(tsnreq->request_seq);
 779         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 780             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 781                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 782                 goto err;
 783         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 784                 i = asoc->strreset_inseq - request_seq - 1;
 785                 result = asoc->strreset_result[i];
 786                 if (result == SCTP_STRRESET_PERFORMED) {
 787                         next_tsn = asoc->ctsn_ack_point + 1;
 788                         init_tsn =
 789                                 sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + 1;
 790                 }
 791                 goto err;
 792         }
 793
 794         if (!sctp_outq_is_empty(&asoc->outqueue)) {
 795                 result = SCTP_STRRESET_IN_PROGRESS;
 796                 goto err;
 797         }
 798
 799         asoc->strreset_inseq++;
 800
 801         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
 802                 goto out;
 803
 804         if (asoc->strreset_outstanding) {
 805                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
 806                 goto out;
 807         }
 808
 809         /* G4: The same processing as though a FWD-TSN chunk (as defined in
 810          *     [RFC3758]) with all streams affected and a new cumulative TSN
 811          *     ACK of the Receiver's Next TSN minus 1 were received MUST be
 812          *     performed.
 813          */
 814         max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
 815         asoc->stream.si->report_ftsn(&asoc->ulpq, max_tsn_seen);
 816
 817         /* G1: Compute an appropriate value for the Receiver's Next TSN -- the
 818          *     TSN that the peer should use to send the next DATA chunk.  The
 819          *     value SHOULD be the smallest TSN not acknowledged by the
 820          *     receiver of the request plus 2^31.
 821          */
 822         init_tsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + (1 << 31);
 823         sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
 824                          init_tsn, GFP_ATOMIC);
 825
 826         /* G3: The same processing as though a SACK chunk with no gap report
 827          *     and a cumulative TSN ACK of the Sender's Next TSN minus 1 were
 828          *     received MUST be performed.
 829          */
 830         sctp_outq_free(&asoc->outqueue);
 831
 832         /* G2: Compute an appropriate value for the local endpoint's next TSN,
 833          *     i.e., the next TSN assigned by the receiver of the SSN/TSN reset
 834          *     chunk.  The value SHOULD be the highest TSN sent by the receiver
 835          *     of the request plus 1.
 836          */
 837         next_tsn = asoc->next_tsn;
 838         asoc->ctsn_ack_point = next_tsn - 1;
 839         asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
 840
 841         /* G5:  The next expected and outgoing SSNs MUST be reset to 0 for all
 842          *      incoming and outgoing streams.
 843          */
 844         for (i = 0; i < stream->outcnt; i++) {
 845                 SCTP_SO(stream, i)->mid = 0;
 846                 SCTP_SO(stream, i)->mid_uo = 0;
 847         }
 848         for (i = 0; i < stream->incnt; i++)
 849                 SCTP_SI(stream, i)->mid = 0;
 850
 851         result = SCTP_STRRESET_PERFORMED;
 852
 853         *evp = sctp_ulpevent_make_assoc_reset_event(asoc, 0, init_tsn,
 854                                                     next_tsn, GFP_ATOMIC);
 855
 856 out:
 857         sctp_update_strreset_result(asoc, result);
 858 err:
 859         return sctp_make_strreset_tsnresp(asoc, result, request_seq,
 860                                           next_tsn, init_tsn);
 861 }
 862
 863 struct sctp_chunk *sctp_process_strreset_addstrm_out(
 864                                 struct sctp_association *asoc,
 865                                 union sctp_params param,
 866                                 struct sctp_ulpevent **evp)
 867 {
 868         struct sctp_strreset_addstrm *addstrm = param.v;
 869         struct sctp_stream *stream = &asoc->stream;
 870         __u32 result = SCTP_STRRESET_DENIED;
 871         __u32 request_seq, incnt;
 872         __u16 in, i;
 873
 874         request_seq = ntohl(addstrm->request_seq);
 875         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 876             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 877                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 878                 goto err;
 879         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 880                 i = asoc->strreset_inseq - request_seq - 1;
 881                 result = asoc->strreset_result[i];
 882                 goto err;
 883         }
 884         asoc->strreset_inseq++;
 885
 886         if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
 887                 goto out;
 888
 889         in = ntohs(addstrm->number_of_streams);
 890         incnt = stream->incnt + in;
 891         if (!in || incnt > SCTP_MAX_STREAM)
 892                 goto out;
 893
 894         if (sctp_stream_alloc_in(stream, incnt, GFP_ATOMIC))
 895                 goto out;
 896
 897         if (asoc->strreset_chunk) {
 898                 if (!sctp_chunk_lookup_strreset_param(
 899                         asoc, 0, SCTP_PARAM_RESET_ADD_IN_STREAMS)) {
 900                         /* same process with outstanding isn't 0 */
 901                         result = SCTP_STRRESET_ERR_IN_PROGRESS;
 902                         goto out;
 903                 }
 904
 905                 asoc->strreset_outstanding--;
 906                 asoc->strreset_outseq++;
 907
 908                 if (!asoc->strreset_outstanding) {
 909                         struct sctp_transport *t;
 910
 911                         t = asoc->strreset_chunk->transport;
 912                         if (del_timer(&t->reconf_timer))
 913                                 sctp_transport_put(t);
 914
 915                         sctp_chunk_put(asoc->strreset_chunk);
 916                         asoc->strreset_chunk = NULL;
 917                 }
 918         }
 919
 920         stream->incnt = incnt;
 921
 922         result = SCTP_STRRESET_PERFORMED;
 923
 924         *evp = sctp_ulpevent_make_stream_change_event(asoc,
 925                 0, ntohs(addstrm->number_of_streams), 0, GFP_ATOMIC);
 926
 927 out:
 928         sctp_update_strreset_result(asoc, result);
 929 err:
 930         return sctp_make_strreset_resp(asoc, result, request_seq);
 931 }
 932
 933 struct sctp_chunk *sctp_process_strreset_addstrm_in(
 934                                 struct sctp_association *asoc,
 935                                 union sctp_params param,
 936                                 struct sctp_ulpevent **evp)
 937 {
 938         struct sctp_strreset_addstrm *addstrm = param.v;
 939         struct sctp_stream *stream = &asoc->stream;
 940         __u32 result = SCTP_STRRESET_DENIED;
 941         struct sctp_chunk *chunk = NULL;
 942         __u32 request_seq, outcnt;
 943         __u16 out, i;
 944         int ret;
 945
 946         request_seq = ntohl(addstrm->request_seq);
 947         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 948             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 949                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 950                 goto err;
 951         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 952                 i = asoc->strreset_inseq - request_seq - 1;
 953                 result = asoc->strreset_result[i];
 954                 if (result == SCTP_STRRESET_PERFORMED)
 955                         return NULL;
 956                 goto err;
 957         }
 958         asoc->strreset_inseq++;
 959
 960         if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
 961                 goto out;
 962
 963         if (asoc->strreset_outstanding) {
 964                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
 965                 goto out;
 966         }
 967
 968         out = ntohs(addstrm->number_of_streams);
 969         outcnt = stream->outcnt + out;
 970         if (!out || outcnt > SCTP_MAX_STREAM)
 971                 goto out;
 972
 973         ret = sctp_stream_alloc_out(stream, outcnt, GFP_ATOMIC);
 974         if (ret)
 975                 goto out;
 976
 977         chunk = sctp_make_strreset_addstrm(asoc, out, 0);
 978         if (!chunk)
 979                 goto out;
 980
 981         asoc->strreset_chunk = chunk;
 982         asoc->strreset_outstanding = 1;
 983         sctp_chunk_hold(asoc->strreset_chunk);
 984
 985         stream->outcnt = outcnt;
 986
 987         result = SCTP_STRRESET_PERFORMED;
 988
 989 out:
 990         sctp_update_strreset_result(asoc, result);
 991 err:
 992         if (!chunk)
 993                 chunk = sctp_make_strreset_resp(asoc, result, request_seq);
 994
 995         return chunk;
 996 }
 997
 998 struct sctp_chunk *sctp_process_strreset_resp(
 999                                 struct sctp_association *asoc,
1000                                 union sctp_params param,
1001                                 struct sctp_ulpevent **evp)
1002 {
1003         struct sctp_stream *stream = &asoc->stream;
1004         struct sctp_strreset_resp *resp = param.v;
1005         struct sctp_transport *t;
1006         __u16 i, nums, flags = 0;
1007         struct sctp_paramhdr *req;
1008         __u32 result;
1009
1010         req = sctp_chunk_lookup_strreset_param(asoc, resp->response_seq, 0);
1011         if (!req)
1012                 return NULL;
1013
1014         result = ntohl(resp->result);
1015         if (result != SCTP_STRRESET_PERFORMED) {
1016                 /* if in progress, do nothing but retransmit */
1017                 if (result == SCTP_STRRESET_IN_PROGRESS)
1018                         return NULL;
1019                 else if (result == SCTP_STRRESET_DENIED)
1020                         flags = SCTP_STREAM_RESET_DENIED;
1021                 else
1022                         flags = SCTP_STREAM_RESET_FAILED;
1023         }
1024
1025         if (req->type == SCTP_PARAM_RESET_OUT_REQUEST) {
1026                 struct sctp_strreset_outreq *outreq;
1027                 __be16 *str_p;
1028
1029                 outreq = (struct sctp_strreset_outreq *)req;
1030                 str_p = outreq->list_of_streams;
1031                 nums = (ntohs(outreq->param_hdr.length) - sizeof(*outreq)) /
1032                        sizeof(__u16);
1033
1034                 if (result == SCTP_STRRESET_PERFORMED) {
1035                         struct sctp_stream_out *sout;
1036                         if (nums) {
1037                                 for (i = 0; i < nums; i++) {
1038                                         sout = SCTP_SO(stream, ntohs(str_p[i]));
1039                                         sout->mid = 0;
1040                                         sout->mid_uo = 0;
1041                                 }
1042                         } else {
1043                                 for (i = 0; i < stream->outcnt; i++) {
1044                                         sout = SCTP_SO(stream, i);
1045                                         sout->mid = 0;
1046                                         sout->mid_uo = 0;
1047                                 }
1048                         }
1049                 }
1050
1051                 flags |= SCTP_STREAM_RESET_OUTGOING_SSN;
1052
1053                 for (i = 0; i < stream->outcnt; i++)
1054                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
1055
1056                 *evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
1057                         nums, str_p, GFP_ATOMIC);
1058         } else if (req->type == SCTP_PARAM_RESET_IN_REQUEST) {
1059                 struct sctp_strreset_inreq *inreq;
1060                 __be16 *str_p;
1061
1062                 /* if the result is performed, it's impossible for inreq */
1063                 if (result == SCTP_STRRESET_PERFORMED)
1064                         return NULL;
1065
1066                 inreq = (struct sctp_strreset_inreq *)req;
1067                 str_p = inreq->list_of_streams;
1068                 nums = (ntohs(inreq->param_hdr.length) - sizeof(*inreq)) /
1069                        sizeof(__u16);
1070
1071                 flags |= SCTP_STREAM_RESET_INCOMING_SSN;
1072
1073                 *evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
1074                         nums, str_p, GFP_ATOMIC);
1075         } else if (req->type == SCTP_PARAM_RESET_TSN_REQUEST) {
1076                 struct sctp_strreset_resptsn *resptsn;
1077                 __u32 stsn, rtsn;
1078
1079                 /* check for resptsn, as sctp_verify_reconf didn't do it*/
1080                 if (ntohs(param.p->length) != sizeof(*resptsn))
1081                         return NULL;
1082
1083                 resptsn = (struct sctp_strreset_resptsn *)resp;
1084                 stsn = ntohl(resptsn->senders_next_tsn);
1085                 rtsn = ntohl(resptsn->receivers_next_tsn);
1086
1087                 if (result == SCTP_STRRESET_PERFORMED) {
1088                         __u32 mtsn = sctp_tsnmap_get_max_tsn_seen(
1089                                                 &asoc->peer.tsn_map);
1090                         LIST_HEAD(temp);
1091
1092                         asoc->stream.si->report_ftsn(&asoc->ulpq, mtsn);
1093
1094                         sctp_tsnmap_init(&asoc->peer.tsn_map,
1095                                          SCTP_TSN_MAP_INITIAL,
1096                                          stsn, GFP_ATOMIC);
1097
1098                         /* Clean up sacked and abandoned queues only. As the
1099                          * out_chunk_list may not be empty, splice it to temp,
1100                          * then get it back after sctp_outq_free is done.
1101                          */
1102                         list_splice_init(&asoc->outqueue.out_chunk_list, &temp);
1103                         sctp_outq_free(&asoc->outqueue);
1104                         list_splice_init(&temp, &asoc->outqueue.out_chunk_list);
1105
1106                         asoc->next_tsn = rtsn;
1107                         asoc->ctsn_ack_point = asoc->next_tsn - 1;
1108                         asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
1109
1110                         for (i = 0; i < stream->outcnt; i++) {
1111                                 SCTP_SO(stream, i)->mid = 0;
1112                                 SCTP_SO(stream, i)->mid_uo = 0;
1113                         }
1114                         for (i = 0; i < stream->incnt; i++)
1115                                 SCTP_SI(stream, i)->mid = 0;
1116                 }
1117
1118                 for (i = 0; i < stream->outcnt; i++)
1119                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
1120
1121                 *evp = sctp_ulpevent_make_assoc_reset_event(asoc, flags,
1122                         stsn, rtsn, GFP_ATOMIC);
1123         } else if (req->type == SCTP_PARAM_RESET_ADD_OUT_STREAMS) {
1124                 struct sctp_strreset_addstrm *addstrm;
1125                 __u16 number;
1126
1127                 addstrm = (struct sctp_strreset_addstrm *)req;
1128                 nums = ntohs(addstrm->number_of_streams);
1129                 number = stream->outcnt - nums;
1130
1131                 if (result == SCTP_STRRESET_PERFORMED)
1132                         for (i = number; i < stream->outcnt; i++)
1133                                 SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
1134                 else
1135                         stream->outcnt = number;
1136
1137                 *evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1138                         0, nums, GFP_ATOMIC);
1139         } else if (req->type == SCTP_PARAM_RESET_ADD_IN_STREAMS) {
1140                 struct sctp_strreset_addstrm *addstrm;
1141
1142                 /* if the result is performed, it's impossible for addstrm in
1143                  * request.
1144                  */
1145                 if (result == SCTP_STRRESET_PERFORMED)
1146                         return NULL;
1147
1148                 addstrm = (struct sctp_strreset_addstrm *)req;
1149                 nums = ntohs(addstrm->number_of_streams);
1150
1151                 *evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1152                         nums, 0, GFP_ATOMIC);
1153         }
1154
1155         asoc->strreset_outstanding--;
1156         asoc->strreset_outseq++;
1157
1158         /* remove everything for this reconf request */
1159         if (!asoc->strreset_outstanding) {
1160                 t = asoc->strreset_chunk->transport;
1161                 if (del_timer(&t->reconf_timer))
1162                         sctp_transport_put(t);
1163
1164                 sctp_chunk_put(asoc->strreset_chunk);
1165                 asoc->strreset_chunk = NULL;
1166         }
1167
1168         return NULL;
1169 }