net/sctp/stream.c

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