net/sctp/stream.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* SCTP kernel implementation
   3  * (C) Copyright IBM Corp. 2001, 2004
   4  * Copyright (c) 1999-2000 Cisco, Inc.
   5  * Copyright (c) 1999-2001 Motorola, Inc.
   6  * Copyright (c) 2001 Intel Corp.
   7  *
   8  * This file is part of the SCTP kernel implementation
   9  *
  10  * This file contains sctp stream maniuplation primitives and helpers.
  11  *
  12  * Please send any bug reports or fixes you make to the
  13  * email address(es):
  14  *    lksctp developers <linux-sctp@vger.kernel.org>
  15  *
  16  * Written or modified by:
  17  *    Xin Long <lucien.xin@gmail.com>
  18  */
  19
  20 #include <linux/list.h>
  21 #include <net/sctp/sctp.h>
  22 #include <net/sctp/sm.h>
  23 #include <net/sctp/stream_sched.h>
  24
  25 static void sctp_stream_shrink_out(struct sctp_stream *stream, __u16 outcnt)
  26 {
  27         struct sctp_association *asoc;
  28         struct sctp_chunk *ch, *temp;
  29         struct sctp_outq *outq;
  30
  31         asoc = container_of(stream, struct sctp_association, stream);
  32         outq = &asoc->outqueue;
  33
  34         list_for_each_entry_safe(ch, temp, &outq->out_chunk_list, list) {
  35                 __u16 sid = sctp_chunk_stream_no(ch);
  36
  37                 if (sid < outcnt)
  38                         continue;
  39
  40                 sctp_sched_dequeue_common(outq, ch);
  41                 /* No need to call dequeue_done here because
  42                  * the chunks are not scheduled by now.
  43                  */
  44
  45                 /* Mark as failed send. */
  46                 sctp_chunk_fail(ch, (__force __u32)SCTP_ERROR_INV_STRM);
  47                 if (asoc->peer.prsctp_capable &&
  48                     SCTP_PR_PRIO_ENABLED(ch->sinfo.sinfo_flags))
  49                         asoc->sent_cnt_removable--;
  50
  51                 sctp_chunk_free(ch);
  52         }
  53 }
  54
  55 /* Migrates chunks from stream queues to new stream queues if needed,
  56  * but not across associations. Also, removes those chunks to streams
  57  * higher than the new max.
  58  */
  59 static void sctp_stream_outq_migrate(struct sctp_stream *stream,
  60                                      struct sctp_stream *new, __u16 outcnt)
  61 {
  62         int i;
  63
  64         if (stream->outcnt > outcnt)
  65                 sctp_stream_shrink_out(stream, outcnt);
  66
  67         if (new) {
  68                 /* Here we actually move the old ext stuff into the new
  69                  * buffer, because we want to keep it. Then
  70                  * sctp_stream_update will swap ->out pointers.
  71                  */
  72                 for (i = 0; i < outcnt; i++) {
  73                         kfree(SCTP_SO(new, i)->ext);
  74                         SCTP_SO(new, i)->ext = SCTP_SO(stream, i)->ext;
  75                         SCTP_SO(stream, i)->ext = NULL;
  76                 }
  77         }
  78
  79         for (i = outcnt; i < stream->outcnt; i++) {
  80                 kfree(SCTP_SO(stream, i)->ext);
  81                 SCTP_SO(stream, i)->ext = NULL;
  82         }
  83 }
  84
  85 static int sctp_stream_alloc_out(struct sctp_stream *stream, __u16 outcnt,
  86                                  gfp_t gfp)
  87 {
  88         int ret;
  89
  90         if (outcnt <= stream->outcnt)
  91                 return 0;
  92
  93         ret = genradix_prealloc(&stream->out, outcnt, gfp);
  94         if (ret)
  95                 return ret;
  96
  97         stream->outcnt = outcnt;
  98         return 0;
  99 }
 100
 101 static int sctp_stream_alloc_in(struct sctp_stream *stream, __u16 incnt,
 102                                 gfp_t gfp)
 103 {
 104         int ret;
 105
 106         if (incnt <= stream->incnt)
 107                 return 0;
 108
 109         ret = genradix_prealloc(&stream->in, incnt, gfp);
 110         if (ret)
 111                 return ret;
 112
 113         stream->incnt = incnt;
 114         return 0;
 115 }
 116
 117 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt,
 118                      gfp_t gfp)
 119 {
 120         struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
 121         int i, ret = 0;
 122
 123         gfp |= __GFP_NOWARN;
 124
 125         /* Initial stream->out size may be very big, so free it and alloc
 126          * a new one with new outcnt to save memory if needed.
 127          */
 128         if (outcnt == stream->outcnt)
 129                 goto handle_in;
 130
 131         /* Filter out chunks queued on streams that won't exist anymore */
 132         sched->unsched_all(stream);
 133         sctp_stream_outq_migrate(stream, NULL, outcnt);
 134         sched->sched_all(stream);
 135
 136         ret = sctp_stream_alloc_out(stream, outcnt, gfp);
 137         if (ret)
 138                 goto out_err;
 139
 140         for (i = 0; i < stream->outcnt; i++)
 141                 SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
 142
 143 handle_in:
 144         sctp_stream_interleave_init(stream);
 145         if (!incnt)
 146                 goto out;
 147
 148         ret = sctp_stream_alloc_in(stream, incnt, gfp);
 149         if (ret)
 150                 goto in_err;
 151
 152         goto out;
 153
 154 in_err:
 155         sched->free(stream);
 156         genradix_free(&stream->in);
 157 out_err:
 158         genradix_free(&stream->out);
 159         stream->outcnt = 0;
 160 out:
 161         return ret;
 162 }
 163
 164 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid)
 165 {
 166         struct sctp_stream_out_ext *soute;
 167         int ret;
 168
 169         soute = kzalloc(sizeof(*soute), GFP_KERNEL);
 170         if (!soute)
 171                 return -ENOMEM;
 172         SCTP_SO(stream, sid)->ext = soute;
 173
 174         ret = sctp_sched_init_sid(stream, sid, GFP_KERNEL);
 175         if (ret) {
 176                 kfree(SCTP_SO(stream, sid)->ext);
 177                 SCTP_SO(stream, sid)->ext = NULL;
 178         }
 179
 180         return ret;
 181 }
 182
 183 void sctp_stream_free(struct sctp_stream *stream)
 184 {
 185         struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
 186         int i;
 187
 188         sched->free(stream);
 189         for (i = 0; i < stream->outcnt; i++)
 190                 kfree(SCTP_SO(stream, i)->ext);
 191         genradix_free(&stream->out);
 192         genradix_free(&stream->in);
 193 }
 194
 195 void sctp_stream_clear(struct sctp_stream *stream)
 196 {
 197         int i;
 198
 199         for (i = 0; i < stream->outcnt; i++) {
 200                 SCTP_SO(stream, i)->mid = 0;
 201                 SCTP_SO(stream, i)->mid_uo = 0;
 202         }
 203
 204         for (i = 0; i < stream->incnt; i++)
 205                 SCTP_SI(stream, i)->mid = 0;
 206 }
 207
 208 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new)
 209 {
 210         struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
 211
 212         sched->unsched_all(stream);
 213         sctp_stream_outq_migrate(stream, new, new->outcnt);
 214         sctp_stream_free(stream);
 215
 216         stream->out = new->out;
 217         stream->in  = new->in;
 218         stream->outcnt = new->outcnt;
 219         stream->incnt  = new->incnt;
 220
 221         sched->sched_all(stream);
 222
 223         new->out.tree.root = NULL;
 224         new->in.tree.root  = NULL;
 225         new->outcnt = 0;
 226         new->incnt  = 0;
 227 }
 228
 229 static int sctp_send_reconf(struct sctp_association *asoc,
 230                             struct sctp_chunk *chunk)
 231 {
 232         int retval = 0;
 233
 234         retval = sctp_primitive_RECONF(asoc->base.net, asoc, chunk);
 235         if (retval)
 236                 sctp_chunk_free(chunk);
 237
 238         return retval;
 239 }
 240
 241 static bool sctp_stream_outq_is_empty(struct sctp_stream *stream,
 242                                       __u16 str_nums, __be16 *str_list)
 243 {
 244         struct sctp_association *asoc;
 245         __u16 i;
 246
 247         asoc = container_of(stream, struct sctp_association, stream);
 248         if (!asoc->outqueue.out_qlen)
 249                 return true;
 250
 251         if (!str_nums)
 252                 return false;
 253
 254         for (i = 0; i < str_nums; i++) {
 255                 __u16 sid = ntohs(str_list[i]);
 256
 257                 if (SCTP_SO(stream, sid)->ext &&
 258                     !list_empty(&SCTP_SO(stream, sid)->ext->outq))
 259                         return false;
 260         }
 261
 262         return true;
 263 }
 264
 265 int sctp_send_reset_streams(struct sctp_association *asoc,
 266                             struct sctp_reset_streams *params)
 267 {
 268         struct sctp_stream *stream = &asoc->stream;
 269         __u16 i, str_nums, *str_list;
 270         struct sctp_chunk *chunk;
 271         int retval = -EINVAL;
 272         __be16 *nstr_list;
 273         bool out, in;
 274
 275         if (!asoc->peer.reconf_capable ||
 276             !(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ)) {
 277                 retval = -ENOPROTOOPT;
 278                 goto out;
 279         }
 280
 281         if (asoc->strreset_outstanding) {
 282                 retval = -EINPROGRESS;
 283                 goto out;
 284         }
 285
 286         out = params->srs_flags & SCTP_STREAM_RESET_OUTGOING;
 287         in  = params->srs_flags & SCTP_STREAM_RESET_INCOMING;
 288         if (!out && !in)
 289                 goto out;
 290
 291         str_nums = params->srs_number_streams;
 292         str_list = params->srs_stream_list;
 293         if (str_nums) {
 294                 int param_len = 0;
 295
 296                 if (out) {
 297                         for (i = 0; i < str_nums; i++)
 298                                 if (str_list[i] >= stream->outcnt)
 299                                         goto out;
 300
 301                         param_len = str_nums * sizeof(__u16) +
 302                                     sizeof(struct sctp_strreset_outreq);
 303                 }
 304
 305                 if (in) {
 306                         for (i = 0; i < str_nums; i++)
 307                                 if (str_list[i] >= stream->incnt)
 308                                         goto out;
 309
 310                         param_len += str_nums * sizeof(__u16) +
 311                                      sizeof(struct sctp_strreset_inreq);
 312                 }
 313
 314                 if (param_len > SCTP_MAX_CHUNK_LEN -
 315                                 sizeof(struct sctp_reconf_chunk))
 316                         goto out;
 317         }
 318
 319         nstr_list = kcalloc(str_nums, sizeof(__be16), GFP_KERNEL);
 320         if (!nstr_list) {
 321                 retval = -ENOMEM;
 322                 goto out;
 323         }
 324
 325         for (i = 0; i < str_nums; i++)
 326                 nstr_list[i] = htons(str_list[i]);
 327
 328         if (out && !sctp_stream_outq_is_empty(stream, str_nums, nstr_list)) {
 329                 kfree(nstr_list);
 330                 retval = -EAGAIN;
 331                 goto out;
 332         }
 333
 334         chunk = sctp_make_strreset_req(asoc, str_nums, nstr_list, out, in);
 335
 336         kfree(nstr_list);
 337
 338         if (!chunk) {
 339                 retval = -ENOMEM;
 340                 goto out;
 341         }
 342
 343         if (out) {
 344                 if (str_nums)
 345                         for (i = 0; i < str_nums; i++)
 346                                 SCTP_SO(stream, str_list[i])->state =
 347                                                        SCTP_STREAM_CLOSED;
 348                 else
 349                         for (i = 0; i < stream->outcnt; i++)
 350                                 SCTP_SO(stream, i)->state = SCTP_STREAM_CLOSED;
 351         }
 352
 353         asoc->strreset_chunk = chunk;
 354         sctp_chunk_hold(asoc->strreset_chunk);
 355
 356         retval = sctp_send_reconf(asoc, chunk);
 357         if (retval) {
 358                 sctp_chunk_put(asoc->strreset_chunk);
 359                 asoc->strreset_chunk = NULL;
 360                 if (!out)
 361                         goto out;
 362
 363                 if (str_nums)
 364                         for (i = 0; i < str_nums; i++)
 365                                 SCTP_SO(stream, str_list[i])->state =
 366                                                        SCTP_STREAM_OPEN;
 367                 else
 368                         for (i = 0; i < stream->outcnt; i++)
 369                                 SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
 370
 371                 goto out;
 372         }
 373
 374         asoc->strreset_outstanding = out + in;
 375
 376 out:
 377         return retval;
 378 }
 379
 380 int sctp_send_reset_assoc(struct sctp_association *asoc)
 381 {
 382         struct sctp_stream *stream = &asoc->stream;
 383         struct sctp_chunk *chunk = NULL;
 384         int retval;
 385         __u16 i;
 386
 387         if (!asoc->peer.reconf_capable ||
 388             !(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
 389                 return -ENOPROTOOPT;
 390
 391         if (asoc->strreset_outstanding)
 392                 return -EINPROGRESS;
 393
 394         if (!sctp_outq_is_empty(&asoc->outqueue))
 395                 return -EAGAIN;
 396
 397         chunk = sctp_make_strreset_tsnreq(asoc);
 398         if (!chunk)
 399                 return -ENOMEM;
 400
 401         /* Block further xmit of data until this request is completed */
 402         for (i = 0; i < stream->outcnt; i++)
 403                 SCTP_SO(stream, i)->state = SCTP_STREAM_CLOSED;
 404
 405         asoc->strreset_chunk = chunk;
 406         sctp_chunk_hold(asoc->strreset_chunk);
 407
 408         retval = sctp_send_reconf(asoc, chunk);
 409         if (retval) {
 410                 sctp_chunk_put(asoc->strreset_chunk);
 411                 asoc->strreset_chunk = NULL;
 412
 413                 for (i = 0; i < stream->outcnt; i++)
 414                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
 415
 416                 return retval;
 417         }
 418
 419         asoc->strreset_outstanding = 1;
 420
 421         return 0;
 422 }
 423
 424 int sctp_send_add_streams(struct sctp_association *asoc,
 425                           struct sctp_add_streams *params)
 426 {
 427         struct sctp_stream *stream = &asoc->stream;
 428         struct sctp_chunk *chunk = NULL;
 429         int retval;
 430         __u32 outcnt, incnt;
 431         __u16 out, in;
 432
 433         if (!asoc->peer.reconf_capable ||
 434             !(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ)) {
 435                 retval = -ENOPROTOOPT;
 436                 goto out;
 437         }
 438
 439         if (asoc->strreset_outstanding) {
 440                 retval = -EINPROGRESS;
 441                 goto out;
 442         }
 443
 444         out = params->sas_outstrms;
 445         in  = params->sas_instrms;
 446         outcnt = stream->outcnt + out;
 447         incnt = stream->incnt + in;
 448         if (outcnt > SCTP_MAX_STREAM || incnt > SCTP_MAX_STREAM ||
 449             (!out && !in)) {
 450                 retval = -EINVAL;
 451                 goto out;
 452         }
 453
 454         if (out) {
 455                 retval = sctp_stream_alloc_out(stream, outcnt, GFP_KERNEL);
 456                 if (retval)
 457                         goto out;
 458         }
 459
 460         chunk = sctp_make_strreset_addstrm(asoc, out, in);
 461         if (!chunk) {
 462                 retval = -ENOMEM;
 463                 goto out;
 464         }
 465
 466         asoc->strreset_chunk = chunk;
 467         sctp_chunk_hold(asoc->strreset_chunk);
 468
 469         retval = sctp_send_reconf(asoc, chunk);
 470         if (retval) {
 471                 sctp_chunk_put(asoc->strreset_chunk);
 472                 asoc->strreset_chunk = NULL;
 473                 goto out;
 474         }
 475
 476         asoc->strreset_outstanding = !!out + !!in;
 477
 478 out:
 479         return retval;
 480 }
 481
 482 static struct sctp_paramhdr *sctp_chunk_lookup_strreset_param(
 483                         struct sctp_association *asoc, __be32 resp_seq,
 484                         __be16 type)
 485 {
 486         struct sctp_chunk *chunk = asoc->strreset_chunk;
 487         struct sctp_reconf_chunk *hdr;
 488         union sctp_params param;
 489
 490         if (!chunk)
 491                 return NULL;
 492
 493         hdr = (struct sctp_reconf_chunk *)chunk->chunk_hdr;
 494         sctp_walk_params(param, hdr, params) {
 495                 /* sctp_strreset_tsnreq is actually the basic structure
 496                  * of all stream reconf params, so it's safe to use it
 497                  * to access request_seq.
 498                  */
 499                 struct sctp_strreset_tsnreq *req = param.v;
 500
 501                 if ((!resp_seq || req->request_seq == resp_seq) &&
 502                     (!type || type == req->param_hdr.type))
 503                         return param.v;
 504         }
 505
 506         return NULL;
 507 }
 508
 509 static void sctp_update_strreset_result(struct sctp_association *asoc,
 510                                         __u32 result)
 511 {
 512         asoc->strreset_result[1] = asoc->strreset_result[0];
 513         asoc->strreset_result[0] = result;
 514 }
 515
 516 struct sctp_chunk *sctp_process_strreset_outreq(
 517                                 struct sctp_association *asoc,
 518                                 union sctp_params param,
 519                                 struct sctp_ulpevent **evp)
 520 {
 521         struct sctp_strreset_outreq *outreq = param.v;
 522         struct sctp_stream *stream = &asoc->stream;
 523         __u32 result = SCTP_STRRESET_DENIED;
 524         __be16 *str_p = NULL;
 525         __u32 request_seq;
 526         __u16 i, nums;
 527
 528         request_seq = ntohl(outreq->request_seq);
 529
 530         if (ntohl(outreq->send_reset_at_tsn) >
 531             sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map)) {
 532                 result = SCTP_STRRESET_IN_PROGRESS;
 533                 goto err;
 534         }
 535
 536         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 537             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 538                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 539                 goto err;
 540         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 541                 i = asoc->strreset_inseq - request_seq - 1;
 542                 result = asoc->strreset_result[i];
 543                 goto err;
 544         }
 545         asoc->strreset_inseq++;
 546
 547         /* Check strreset_enable after inseq inc, as sender cannot tell
 548          * the peer doesn't enable strreset after receiving response with
 549          * result denied, as well as to keep consistent with bsd.
 550          */
 551         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
 552                 goto out;
 553
 554         nums = (ntohs(param.p->length) - sizeof(*outreq)) / sizeof(__u16);
 555         str_p = outreq->list_of_streams;
 556         for (i = 0; i < nums; i++) {
 557                 if (ntohs(str_p[i]) >= stream->incnt) {
 558                         result = SCTP_STRRESET_ERR_WRONG_SSN;
 559                         goto out;
 560                 }
 561         }
 562
 563         if (asoc->strreset_chunk) {
 564                 if (!sctp_chunk_lookup_strreset_param(
 565                                 asoc, outreq->response_seq,
 566                                 SCTP_PARAM_RESET_IN_REQUEST)) {
 567                         /* same process with outstanding isn't 0 */
 568                         result = SCTP_STRRESET_ERR_IN_PROGRESS;
 569                         goto out;
 570                 }
 571
 572                 asoc->strreset_outstanding--;
 573                 asoc->strreset_outseq++;
 574
 575                 if (!asoc->strreset_outstanding) {
 576                         struct sctp_transport *t;
 577
 578                         t = asoc->strreset_chunk->transport;
 579                         if (del_timer(&t->reconf_timer))
 580                                 sctp_transport_put(t);
 581
 582                         sctp_chunk_put(asoc->strreset_chunk);
 583                         asoc->strreset_chunk = NULL;
 584                 }
 585         }
 586
 587         if (nums)
 588                 for (i = 0; i < nums; i++)
 589                         SCTP_SI(stream, ntohs(str_p[i]))->mid = 0;
 590         else
 591                 for (i = 0; i < stream->incnt; i++)
 592                         SCTP_SI(stream, i)->mid = 0;
 593
 594         result = SCTP_STRRESET_PERFORMED;
 595
 596         *evp = sctp_ulpevent_make_stream_reset_event(asoc,
 597                 SCTP_STREAM_RESET_INCOMING_SSN, nums, str_p, GFP_ATOMIC);
 598
 599 out:
 600         sctp_update_strreset_result(asoc, result);
 601 err:
 602         return sctp_make_strreset_resp(asoc, result, request_seq);
 603 }
 604
 605 struct sctp_chunk *sctp_process_strreset_inreq(
 606                                 struct sctp_association *asoc,
 607                                 union sctp_params param,
 608                                 struct sctp_ulpevent **evp)
 609 {
 610         struct sctp_strreset_inreq *inreq = param.v;
 611         struct sctp_stream *stream = &asoc->stream;
 612         __u32 result = SCTP_STRRESET_DENIED;
 613         struct sctp_chunk *chunk = NULL;
 614         __u32 request_seq;
 615         __u16 i, nums;
 616         __be16 *str_p;
 617
 618         request_seq = ntohl(inreq->request_seq);
 619         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 620             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 621                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 622                 goto err;
 623         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 624                 i = asoc->strreset_inseq - request_seq - 1;
 625                 result = asoc->strreset_result[i];
 626                 if (result == SCTP_STRRESET_PERFORMED)
 627                         return NULL;
 628                 goto err;
 629         }
 630         asoc->strreset_inseq++;
 631
 632         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
 633                 goto out;
 634
 635         if (asoc->strreset_outstanding) {
 636                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
 637                 goto out;
 638         }
 639
 640         nums = (ntohs(param.p->length) - sizeof(*inreq)) / sizeof(__u16);
 641         str_p = inreq->list_of_streams;
 642         for (i = 0; i < nums; i++) {
 643                 if (ntohs(str_p[i]) >= stream->outcnt) {
 644                         result = SCTP_STRRESET_ERR_WRONG_SSN;
 645                         goto out;
 646                 }
 647         }
 648
 649         if (!sctp_stream_outq_is_empty(stream, nums, str_p)) {
 650                 result = SCTP_STRRESET_IN_PROGRESS;
 651                 asoc->strreset_inseq--;
 652                 goto err;
 653         }
 654
 655         chunk = sctp_make_strreset_req(asoc, nums, str_p, 1, 0);
 656         if (!chunk)
 657                 goto out;
 658
 659         if (nums)
 660                 for (i = 0; i < nums; i++)
 661                         SCTP_SO(stream, ntohs(str_p[i]))->state =
 662                                                SCTP_STREAM_CLOSED;
 663         else
 664                 for (i = 0; i < stream->outcnt; i++)
 665                         SCTP_SO(stream, i)->state = SCTP_STREAM_CLOSED;
 666
 667         asoc->strreset_chunk = chunk;
 668         asoc->strreset_outstanding = 1;
 669         sctp_chunk_hold(asoc->strreset_chunk);
 670
 671         result = SCTP_STRRESET_PERFORMED;
 672
 673 out:
 674         sctp_update_strreset_result(asoc, result);
 675 err:
 676         if (!chunk)
 677                 chunk =  sctp_make_strreset_resp(asoc, result, request_seq);
 678
 679         return chunk;
 680 }
 681
 682 struct sctp_chunk *sctp_process_strreset_tsnreq(
 683                                 struct sctp_association *asoc,
 684                                 union sctp_params param,
 685                                 struct sctp_ulpevent **evp)
 686 {
 687         __u32 init_tsn = 0, next_tsn = 0, max_tsn_seen;
 688         struct sctp_strreset_tsnreq *tsnreq = param.v;
 689         struct sctp_stream *stream = &asoc->stream;
 690         __u32 result = SCTP_STRRESET_DENIED;
 691         __u32 request_seq;
 692         __u16 i;
 693
 694         request_seq = ntohl(tsnreq->request_seq);
 695         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 696             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 697                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 698                 goto err;
 699         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 700                 i = asoc->strreset_inseq - request_seq - 1;
 701                 result = asoc->strreset_result[i];
 702                 if (result == SCTP_STRRESET_PERFORMED) {
 703                         next_tsn = asoc->ctsn_ack_point + 1;
 704                         init_tsn =
 705                                 sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + 1;
 706                 }
 707                 goto err;
 708         }
 709
 710         if (!sctp_outq_is_empty(&asoc->outqueue)) {
 711                 result = SCTP_STRRESET_IN_PROGRESS;
 712                 goto err;
 713         }
 714
 715         asoc->strreset_inseq++;
 716
 717         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
 718                 goto out;
 719
 720         if (asoc->strreset_outstanding) {
 721                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
 722                 goto out;
 723         }
 724
 725         /* G4: The same processing as though a FWD-TSN chunk (as defined in
 726          *     [RFC3758]) with all streams affected and a new cumulative TSN
 727          *     ACK of the Receiver's Next TSN minus 1 were received MUST be
 728          *     performed.
 729          */
 730         max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
 731         asoc->stream.si->report_ftsn(&asoc->ulpq, max_tsn_seen);
 732
 733         /* G1: Compute an appropriate value for the Receiver's Next TSN -- the
 734          *     TSN that the peer should use to send the next DATA chunk.  The
 735          *     value SHOULD be the smallest TSN not acknowledged by the
 736          *     receiver of the request plus 2^31.
 737          */
 738         init_tsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + (1 << 31);
 739         sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
 740                          init_tsn, GFP_ATOMIC);
 741
 742         /* G3: The same processing as though a SACK chunk with no gap report
 743          *     and a cumulative TSN ACK of the Sender's Next TSN minus 1 were
 744          *     received MUST be performed.
 745          */
 746         sctp_outq_free(&asoc->outqueue);
 747
 748         /* G2: Compute an appropriate value for the local endpoint's next TSN,
 749          *     i.e., the next TSN assigned by the receiver of the SSN/TSN reset
 750          *     chunk.  The value SHOULD be the highest TSN sent by the receiver
 751          *     of the request plus 1.
 752          */
 753         next_tsn = asoc->next_tsn;
 754         asoc->ctsn_ack_point = next_tsn - 1;
 755         asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
 756
 757         /* G5:  The next expected and outgoing SSNs MUST be reset to 0 for all
 758          *      incoming and outgoing streams.
 759          */
 760         for (i = 0; i < stream->outcnt; i++) {
 761                 SCTP_SO(stream, i)->mid = 0;
 762                 SCTP_SO(stream, i)->mid_uo = 0;
 763         }
 764         for (i = 0; i < stream->incnt; i++)
 765                 SCTP_SI(stream, i)->mid = 0;
 766
 767         result = SCTP_STRRESET_PERFORMED;
 768
 769         *evp = sctp_ulpevent_make_assoc_reset_event(asoc, 0, init_tsn,
 770                                                     next_tsn, GFP_ATOMIC);
 771
 772 out:
 773         sctp_update_strreset_result(asoc, result);
 774 err:
 775         return sctp_make_strreset_tsnresp(asoc, result, request_seq,
 776                                           next_tsn, init_tsn);
 777 }
 778
 779 struct sctp_chunk *sctp_process_strreset_addstrm_out(
 780                                 struct sctp_association *asoc,
 781                                 union sctp_params param,
 782                                 struct sctp_ulpevent **evp)
 783 {
 784         struct sctp_strreset_addstrm *addstrm = param.v;
 785         struct sctp_stream *stream = &asoc->stream;
 786         __u32 result = SCTP_STRRESET_DENIED;
 787         __u32 request_seq, incnt;
 788         __u16 in, i;
 789
 790         request_seq = ntohl(addstrm->request_seq);
 791         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 792             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 793                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 794                 goto err;
 795         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 796                 i = asoc->strreset_inseq - request_seq - 1;
 797                 result = asoc->strreset_result[i];
 798                 goto err;
 799         }
 800         asoc->strreset_inseq++;
 801
 802         if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
 803                 goto out;
 804
 805         in = ntohs(addstrm->number_of_streams);
 806         incnt = stream->incnt + in;
 807         if (!in || incnt > SCTP_MAX_STREAM)
 808                 goto out;
 809
 810         if (sctp_stream_alloc_in(stream, incnt, GFP_ATOMIC))
 811                 goto out;
 812
 813         if (asoc->strreset_chunk) {
 814                 if (!sctp_chunk_lookup_strreset_param(
 815                         asoc, 0, SCTP_PARAM_RESET_ADD_IN_STREAMS)) {
 816                         /* same process with outstanding isn't 0 */
 817                         result = SCTP_STRRESET_ERR_IN_PROGRESS;
 818                         goto out;
 819                 }
 820
 821                 asoc->strreset_outstanding--;
 822                 asoc->strreset_outseq++;
 823
 824                 if (!asoc->strreset_outstanding) {
 825                         struct sctp_transport *t;
 826
 827                         t = asoc->strreset_chunk->transport;
 828                         if (del_timer(&t->reconf_timer))
 829                                 sctp_transport_put(t);
 830
 831                         sctp_chunk_put(asoc->strreset_chunk);
 832                         asoc->strreset_chunk = NULL;
 833                 }
 834         }
 835
 836         stream->incnt = incnt;
 837
 838         result = SCTP_STRRESET_PERFORMED;
 839
 840         *evp = sctp_ulpevent_make_stream_change_event(asoc,
 841                 0, ntohs(addstrm->number_of_streams), 0, GFP_ATOMIC);
 842
 843 out:
 844         sctp_update_strreset_result(asoc, result);
 845 err:
 846         return sctp_make_strreset_resp(asoc, result, request_seq);
 847 }
 848
 849 struct sctp_chunk *sctp_process_strreset_addstrm_in(
 850                                 struct sctp_association *asoc,
 851                                 union sctp_params param,
 852                                 struct sctp_ulpevent **evp)
 853 {
 854         struct sctp_strreset_addstrm *addstrm = param.v;
 855         struct sctp_stream *stream = &asoc->stream;
 856         __u32 result = SCTP_STRRESET_DENIED;
 857         struct sctp_chunk *chunk = NULL;
 858         __u32 request_seq, outcnt;
 859         __u16 out, i;
 860         int ret;
 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                 if (result == SCTP_STRRESET_PERFORMED)
 871                         return NULL;
 872                 goto err;
 873         }
 874         asoc->strreset_inseq++;
 875
 876         if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
 877                 goto out;
 878
 879         if (asoc->strreset_outstanding) {
 880                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
 881                 goto out;
 882         }
 883
 884         out = ntohs(addstrm->number_of_streams);
 885         outcnt = stream->outcnt + out;
 886         if (!out || outcnt > SCTP_MAX_STREAM)
 887                 goto out;
 888
 889         ret = sctp_stream_alloc_out(stream, outcnt, GFP_ATOMIC);
 890         if (ret)
 891                 goto out;
 892
 893         chunk = sctp_make_strreset_addstrm(asoc, out, 0);
 894         if (!chunk)
 895                 goto out;
 896
 897         asoc->strreset_chunk = chunk;
 898         asoc->strreset_outstanding = 1;
 899         sctp_chunk_hold(asoc->strreset_chunk);
 900
 901         stream->outcnt = outcnt;
 902
 903         result = SCTP_STRRESET_PERFORMED;
 904
 905 out:
 906         sctp_update_strreset_result(asoc, result);
 907 err:
 908         if (!chunk)
 909                 chunk = sctp_make_strreset_resp(asoc, result, request_seq);
 910
 911         return chunk;
 912 }
 913
 914 struct sctp_chunk *sctp_process_strreset_resp(
 915                                 struct sctp_association *asoc,
 916                                 union sctp_params param,
 917                                 struct sctp_ulpevent **evp)
 918 {
 919         struct sctp_stream *stream = &asoc->stream;
 920         struct sctp_strreset_resp *resp = param.v;
 921         struct sctp_transport *t;
 922         __u16 i, nums, flags = 0;
 923         struct sctp_paramhdr *req;
 924         __u32 result;
 925
 926         req = sctp_chunk_lookup_strreset_param(asoc, resp->response_seq, 0);
 927         if (!req)
 928                 return NULL;
 929
 930         result = ntohl(resp->result);
 931         if (result != SCTP_STRRESET_PERFORMED) {
 932                 /* if in progress, do nothing but retransmit */
 933                 if (result == SCTP_STRRESET_IN_PROGRESS)
 934                         return NULL;
 935                 else if (result == SCTP_STRRESET_DENIED)
 936                         flags = SCTP_STREAM_RESET_DENIED;
 937                 else
 938                         flags = SCTP_STREAM_RESET_FAILED;
 939         }
 940
 941         if (req->type == SCTP_PARAM_RESET_OUT_REQUEST) {
 942                 struct sctp_strreset_outreq *outreq;
 943                 __be16 *str_p;
 944
 945                 outreq = (struct sctp_strreset_outreq *)req;
 946                 str_p = outreq->list_of_streams;
 947                 nums = (ntohs(outreq->param_hdr.length) - sizeof(*outreq)) /
 948                        sizeof(__u16);
 949
 950                 if (result == SCTP_STRRESET_PERFORMED) {
 951                         struct sctp_stream_out *sout;
 952                         if (nums) {
 953                                 for (i = 0; i < nums; i++) {
 954                                         sout = SCTP_SO(stream, ntohs(str_p[i]));
 955                                         sout->mid = 0;
 956                                         sout->mid_uo = 0;
 957                                 }
 958                         } else {
 959                                 for (i = 0; i < stream->outcnt; i++) {
 960                                         sout = SCTP_SO(stream, i);
 961                                         sout->mid = 0;
 962                                         sout->mid_uo = 0;
 963                                 }
 964                         }
 965                 }
 966
 967                 flags |= SCTP_STREAM_RESET_OUTGOING_SSN;
 968
 969                 for (i = 0; i < stream->outcnt; i++)
 970                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
 971
 972                 *evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
 973                         nums, str_p, GFP_ATOMIC);
 974         } else if (req->type == SCTP_PARAM_RESET_IN_REQUEST) {
 975                 struct sctp_strreset_inreq *inreq;
 976                 __be16 *str_p;
 977
 978                 /* if the result is performed, it's impossible for inreq */
 979                 if (result == SCTP_STRRESET_PERFORMED)
 980                         return NULL;
 981
 982                 inreq = (struct sctp_strreset_inreq *)req;
 983                 str_p = inreq->list_of_streams;
 984                 nums = (ntohs(inreq->param_hdr.length) - sizeof(*inreq)) /
 985                        sizeof(__u16);
 986
 987                 flags |= SCTP_STREAM_RESET_INCOMING_SSN;
 988
 989                 *evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
 990                         nums, str_p, GFP_ATOMIC);
 991         } else if (req->type == SCTP_PARAM_RESET_TSN_REQUEST) {
 992                 struct sctp_strreset_resptsn *resptsn;
 993                 __u32 stsn, rtsn;
 994
 995                 /* check for resptsn, as sctp_verify_reconf didn't do it*/
 996                 if (ntohs(param.p->length) != sizeof(*resptsn))
 997                         return NULL;
 998
 999                 resptsn = (struct sctp_strreset_resptsn *)resp;
1000                 stsn = ntohl(resptsn->senders_next_tsn);
1001                 rtsn = ntohl(resptsn->receivers_next_tsn);
1002
1003                 if (result == SCTP_STRRESET_PERFORMED) {
1004                         __u32 mtsn = sctp_tsnmap_get_max_tsn_seen(
1005                                                 &asoc->peer.tsn_map);
1006                         LIST_HEAD(temp);
1007
1008                         asoc->stream.si->report_ftsn(&asoc->ulpq, mtsn);
1009
1010                         sctp_tsnmap_init(&asoc->peer.tsn_map,
1011                                          SCTP_TSN_MAP_INITIAL,
1012                                          stsn, GFP_ATOMIC);
1013
1014                         /* Clean up sacked and abandoned queues only. As the
1015                          * out_chunk_list may not be empty, splice it to temp,
1016                          * then get it back after sctp_outq_free is done.
1017                          */
1018                         list_splice_init(&asoc->outqueue.out_chunk_list, &temp);
1019                         sctp_outq_free(&asoc->outqueue);
1020                         list_splice_init(&temp, &asoc->outqueue.out_chunk_list);
1021
1022                         asoc->next_tsn = rtsn;
1023                         asoc->ctsn_ack_point = asoc->next_tsn - 1;
1024                         asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
1025
1026                         for (i = 0; i < stream->outcnt; i++) {
1027                                 SCTP_SO(stream, i)->mid = 0;
1028                                 SCTP_SO(stream, i)->mid_uo = 0;
1029                         }
1030                         for (i = 0; i < stream->incnt; i++)
1031                                 SCTP_SI(stream, i)->mid = 0;
1032                 }
1033
1034                 for (i = 0; i < stream->outcnt; i++)
1035                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
1036
1037                 *evp = sctp_ulpevent_make_assoc_reset_event(asoc, flags,
1038                         stsn, rtsn, GFP_ATOMIC);
1039         } else if (req->type == SCTP_PARAM_RESET_ADD_OUT_STREAMS) {
1040                 struct sctp_strreset_addstrm *addstrm;
1041                 __u16 number;
1042
1043                 addstrm = (struct sctp_strreset_addstrm *)req;
1044                 nums = ntohs(addstrm->number_of_streams);
1045                 number = stream->outcnt - nums;
1046
1047                 if (result == SCTP_STRRESET_PERFORMED) {
1048                         for (i = number; i < stream->outcnt; i++)
1049                                 SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
1050                 } else {
1051                         sctp_stream_shrink_out(stream, number);
1052                         stream->outcnt = number;
1053                 }
1054
1055                 *evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1056                         0, nums, GFP_ATOMIC);
1057         } else if (req->type == SCTP_PARAM_RESET_ADD_IN_STREAMS) {
1058                 struct sctp_strreset_addstrm *addstrm;
1059
1060                 /* if the result is performed, it's impossible for addstrm in
1061                  * request.
1062                  */
1063                 if (result == SCTP_STRRESET_PERFORMED)
1064                         return NULL;
1065
1066                 addstrm = (struct sctp_strreset_addstrm *)req;
1067                 nums = ntohs(addstrm->number_of_streams);
1068
1069                 *evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1070                         nums, 0, GFP_ATOMIC);
1071         }
1072
1073         asoc->strreset_outstanding--;
1074         asoc->strreset_outseq++;
1075
1076         /* remove everything for this reconf request */
1077         if (!asoc->strreset_outstanding) {
1078                 t = asoc->strreset_chunk->transport;
1079                 if (del_timer(&t->reconf_timer))
1080                         sctp_transport_put(t);
1081
1082                 sctp_chunk_put(asoc->strreset_chunk);
1083                 asoc->strreset_chunk = NULL;
1084         }
1085
1086         return NULL;
1087 }