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 static void sctp_stream_free_ext(struct sctp_stream *stream, __u16 sid)
  56 {
  57         struct sctp_sched_ops *sched;
  58
  59         if (!SCTP_SO(stream, sid)->ext)
  60                 return;
  61
  62         sched = sctp_sched_ops_from_stream(stream);
  63         sched->free_sid(stream, sid);
  64         kfree(SCTP_SO(stream, sid)->ext);
  65         SCTP_SO(stream, sid)->ext = NULL;
  66 }
  67
  68 /* Migrates chunks from stream queues to new stream queues if needed,
  69  * but not across associations. Also, removes those chunks to streams
  70  * higher than the new max.
  71  */
  72 static void sctp_stream_outq_migrate(struct sctp_stream *stream,
  73                                      struct sctp_stream *new, __u16 outcnt)
  74 {
  75         int i;
  76
  77         if (stream->outcnt > outcnt)
  78                 sctp_stream_shrink_out(stream, outcnt);
  79
  80         if (new) {
  81                 /* Here we actually move the old ext stuff into the new
  82                  * buffer, because we want to keep it. Then
  83                  * sctp_stream_update will swap ->out pointers.
  84                  */
  85                 for (i = 0; i < outcnt; i++) {
  86                         sctp_stream_free_ext(new, i);
  87                         SCTP_SO(new, i)->ext = SCTP_SO(stream, i)->ext;
  88                         SCTP_SO(stream, i)->ext = NULL;
  89                 }
  90         }
  91
  92         for (i = outcnt; i < stream->outcnt; i++)
  93                 sctp_stream_free_ext(stream, i);
  94 }
  95
  96 static int sctp_stream_alloc_out(struct sctp_stream *stream, __u16 outcnt,
  97                                  gfp_t gfp)
  98 {
  99         int ret;
 100
 101         if (outcnt <= stream->outcnt)
 102                 goto out;
 103
 104         ret = genradix_prealloc(&stream->out, outcnt, gfp);
 105         if (ret)
 106                 return ret;
 107
 108 out:
 109         stream->outcnt = outcnt;
 110         return 0;
 111 }
 112
 113 static int sctp_stream_alloc_in(struct sctp_stream *stream, __u16 incnt,
 114                                 gfp_t gfp)
 115 {
 116         int ret;
 117
 118         if (incnt <= stream->incnt)
 119                 goto out;
 120
 121         ret = genradix_prealloc(&stream->in, incnt, gfp);
 122         if (ret)
 123                 return ret;
 124
 125 out:
 126         stream->incnt = incnt;
 127         return 0;
 128 }
 129
 130 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt,
 131                      gfp_t gfp)
 132 {
 133         struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream);
 134         int i, ret = 0;
 135
 136         gfp |= __GFP_NOWARN;
 137
 138         /* Initial stream->out size may be very big, so free it and alloc
 139          * a new one with new outcnt to save memory if needed.
 140          */
 141         if (outcnt == stream->outcnt)
 142                 goto handle_in;
 143
 144         /* Filter out chunks queued on streams that won't exist anymore */
 145         sched->unsched_all(stream);
 146         sctp_stream_outq_migrate(stream, NULL, outcnt);
 147         sched->sched_all(stream);
 148
 149         ret = sctp_stream_alloc_out(stream, outcnt, gfp);
 150         if (ret)
 151                 return ret;
 152
 153         for (i = 0; i < stream->outcnt; i++)
 154                 SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
 155
 156 handle_in:
 157         sctp_stream_interleave_init(stream);
 158         if (!incnt)
 159                 return 0;
 160
 161         return sctp_stream_alloc_in(stream, incnt, gfp);
 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->unsched_all(stream);
 189         for (i = 0; i < stream->outcnt; i++)
 190                 sctp_stream_free_ext(stream, i);
 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         struct net *net = sock_net(asoc->base.sk);
 233         int retval = 0;
 234
 235         retval = sctp_primitive_RECONF(net, asoc, chunk);
 236         if (retval)
 237                 sctp_chunk_free(chunk);
 238
 239         return retval;
 240 }
 241
 242 static bool sctp_stream_outq_is_empty(struct sctp_stream *stream,
 243                                       __u16 str_nums, __be16 *str_list)
 244 {
 245         struct sctp_association *asoc;
 246         __u16 i;
 247
 248         asoc = container_of(stream, struct sctp_association, stream);
 249         if (!asoc->outqueue.out_qlen)
 250                 return true;
 251
 252         if (!str_nums)
 253                 return false;
 254
 255         for (i = 0; i < str_nums; i++) {
 256                 __u16 sid = ntohs(str_list[i]);
 257
 258                 if (SCTP_SO(stream, sid)->ext &&
 259                     !list_empty(&SCTP_SO(stream, sid)->ext->outq))
 260                         return false;
 261         }
 262
 263         return true;
 264 }
 265
 266 int sctp_send_reset_streams(struct sctp_association *asoc,
 267                             struct sctp_reset_streams *params)
 268 {
 269         struct sctp_stream *stream = &asoc->stream;
 270         __u16 i, str_nums, *str_list;
 271         struct sctp_chunk *chunk;
 272         int retval = -EINVAL;
 273         __be16 *nstr_list;
 274         bool out, in;
 275
 276         if (!asoc->peer.reconf_capable ||
 277             !(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ)) {
 278                 retval = -ENOPROTOOPT;
 279                 goto out;
 280         }
 281
 282         if (asoc->strreset_outstanding) {
 283                 retval = -EINPROGRESS;
 284                 goto out;
 285         }
 286
 287         out = params->srs_flags & SCTP_STREAM_RESET_OUTGOING;
 288         in  = params->srs_flags & SCTP_STREAM_RESET_INCOMING;
 289         if (!out && !in)
 290                 goto out;
 291
 292         str_nums = params->srs_number_streams;
 293         str_list = params->srs_stream_list;
 294         if (str_nums) {
 295                 int param_len = 0;
 296
 297                 if (out) {
 298                         for (i = 0; i < str_nums; i++)
 299                                 if (str_list[i] >= stream->outcnt)
 300                                         goto out;
 301
 302                         param_len = str_nums * sizeof(__u16) +
 303                                     sizeof(struct sctp_strreset_outreq);
 304                 }
 305
 306                 if (in) {
 307                         for (i = 0; i < str_nums; i++)
 308                                 if (str_list[i] >= stream->incnt)
 309                                         goto out;
 310
 311                         param_len += str_nums * sizeof(__u16) +
 312                                      sizeof(struct sctp_strreset_inreq);
 313                 }
 314
 315                 if (param_len > SCTP_MAX_CHUNK_LEN -
 316                                 sizeof(struct sctp_reconf_chunk))
 317                         goto out;
 318         }
 319
 320         nstr_list = kcalloc(str_nums, sizeof(__be16), GFP_KERNEL);
 321         if (!nstr_list) {
 322                 retval = -ENOMEM;
 323                 goto out;
 324         }
 325
 326         for (i = 0; i < str_nums; i++)
 327                 nstr_list[i] = htons(str_list[i]);
 328
 329         if (out && !sctp_stream_outq_is_empty(stream, str_nums, nstr_list)) {
 330                 kfree(nstr_list);
 331                 retval = -EAGAIN;
 332                 goto out;
 333         }
 334
 335         chunk = sctp_make_strreset_req(asoc, str_nums, nstr_list, out, in);
 336
 337         kfree(nstr_list);
 338
 339         if (!chunk) {
 340                 retval = -ENOMEM;
 341                 goto out;
 342         }
 343
 344         if (out) {
 345                 if (str_nums)
 346                         for (i = 0; i < str_nums; i++)
 347                                 SCTP_SO(stream, str_list[i])->state =
 348                                                        SCTP_STREAM_CLOSED;
 349                 else
 350                         for (i = 0; i < stream->outcnt; i++)
 351                                 SCTP_SO(stream, i)->state = SCTP_STREAM_CLOSED;
 352         }
 353
 354         asoc->strreset_chunk = chunk;
 355         sctp_chunk_hold(asoc->strreset_chunk);
 356
 357         retval = sctp_send_reconf(asoc, chunk);
 358         if (retval) {
 359                 sctp_chunk_put(asoc->strreset_chunk);
 360                 asoc->strreset_chunk = NULL;
 361                 if (!out)
 362                         goto out;
 363
 364                 if (str_nums)
 365                         for (i = 0; i < str_nums; i++)
 366                                 SCTP_SO(stream, str_list[i])->state =
 367                                                        SCTP_STREAM_OPEN;
 368                 else
 369                         for (i = 0; i < stream->outcnt; i++)
 370                                 SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
 371
 372                 goto out;
 373         }
 374
 375         asoc->strreset_outstanding = out + in;
 376
 377 out:
 378         return retval;
 379 }
 380
 381 int sctp_send_reset_assoc(struct sctp_association *asoc)
 382 {
 383         struct sctp_stream *stream = &asoc->stream;
 384         struct sctp_chunk *chunk = NULL;
 385         int retval;
 386         __u16 i;
 387
 388         if (!asoc->peer.reconf_capable ||
 389             !(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
 390                 return -ENOPROTOOPT;
 391
 392         if (asoc->strreset_outstanding)
 393                 return -EINPROGRESS;
 394
 395         if (!sctp_outq_is_empty(&asoc->outqueue))
 396                 return -EAGAIN;
 397
 398         chunk = sctp_make_strreset_tsnreq(asoc);
 399         if (!chunk)
 400                 return -ENOMEM;
 401
 402         /* Block further xmit of data until this request is completed */
 403         for (i = 0; i < stream->outcnt; i++)
 404                 SCTP_SO(stream, i)->state = SCTP_STREAM_CLOSED;
 405
 406         asoc->strreset_chunk = chunk;
 407         sctp_chunk_hold(asoc->strreset_chunk);
 408
 409         retval = sctp_send_reconf(asoc, chunk);
 410         if (retval) {
 411                 sctp_chunk_put(asoc->strreset_chunk);
 412                 asoc->strreset_chunk = NULL;
 413
 414                 for (i = 0; i < stream->outcnt; i++)
 415                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
 416
 417                 return retval;
 418         }
 419
 420         asoc->strreset_outstanding = 1;
 421
 422         return 0;
 423 }
 424
 425 int sctp_send_add_streams(struct sctp_association *asoc,
 426                           struct sctp_add_streams *params)
 427 {
 428         struct sctp_stream *stream = &asoc->stream;
 429         struct sctp_chunk *chunk = NULL;
 430         int retval;
 431         __u32 outcnt, incnt;
 432         __u16 out, in;
 433
 434         if (!asoc->peer.reconf_capable ||
 435             !(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ)) {
 436                 retval = -ENOPROTOOPT;
 437                 goto out;
 438         }
 439
 440         if (asoc->strreset_outstanding) {
 441                 retval = -EINPROGRESS;
 442                 goto out;
 443         }
 444
 445         out = params->sas_outstrms;
 446         in  = params->sas_instrms;
 447         outcnt = stream->outcnt + out;
 448         incnt = stream->incnt + in;
 449         if (outcnt > SCTP_MAX_STREAM || incnt > SCTP_MAX_STREAM ||
 450             (!out && !in)) {
 451                 retval = -EINVAL;
 452                 goto out;
 453         }
 454
 455         if (out) {
 456                 retval = sctp_stream_alloc_out(stream, outcnt, GFP_KERNEL);
 457                 if (retval)
 458                         goto out;
 459         }
 460
 461         chunk = sctp_make_strreset_addstrm(asoc, out, in);
 462         if (!chunk) {
 463                 retval = -ENOMEM;
 464                 goto out;
 465         }
 466
 467         asoc->strreset_chunk = chunk;
 468         sctp_chunk_hold(asoc->strreset_chunk);
 469
 470         retval = sctp_send_reconf(asoc, chunk);
 471         if (retval) {
 472                 sctp_chunk_put(asoc->strreset_chunk);
 473                 asoc->strreset_chunk = NULL;
 474                 goto out;
 475         }
 476
 477         asoc->strreset_outstanding = !!out + !!in;
 478
 479 out:
 480         return retval;
 481 }
 482
 483 static struct sctp_paramhdr *sctp_chunk_lookup_strreset_param(
 484                         struct sctp_association *asoc, __be32 resp_seq,
 485                         __be16 type)
 486 {
 487         struct sctp_chunk *chunk = asoc->strreset_chunk;
 488         struct sctp_reconf_chunk *hdr;
 489         union sctp_params param;
 490
 491         if (!chunk)
 492                 return NULL;
 493
 494         hdr = (struct sctp_reconf_chunk *)chunk->chunk_hdr;
 495         sctp_walk_params(param, hdr, params) {
 496                 /* sctp_strreset_tsnreq is actually the basic structure
 497                  * of all stream reconf params, so it's safe to use it
 498                  * to access request_seq.
 499                  */
 500                 struct sctp_strreset_tsnreq *req = param.v;
 501
 502                 if ((!resp_seq || req->request_seq == resp_seq) &&
 503                     (!type || type == req->param_hdr.type))
 504                         return param.v;
 505         }
 506
 507         return NULL;
 508 }
 509
 510 static void sctp_update_strreset_result(struct sctp_association *asoc,
 511                                         __u32 result)
 512 {
 513         asoc->strreset_result[1] = asoc->strreset_result[0];
 514         asoc->strreset_result[0] = result;
 515 }
 516
 517 struct sctp_chunk *sctp_process_strreset_outreq(
 518                                 struct sctp_association *asoc,
 519                                 union sctp_params param,
 520                                 struct sctp_ulpevent **evp)
 521 {
 522         struct sctp_strreset_outreq *outreq = param.v;
 523         struct sctp_stream *stream = &asoc->stream;
 524         __u32 result = SCTP_STRRESET_DENIED;
 525         __be16 *str_p = NULL;
 526         __u32 request_seq;
 527         __u16 i, nums;
 528
 529         request_seq = ntohl(outreq->request_seq);
 530
 531         if (ntohl(outreq->send_reset_at_tsn) >
 532             sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map)) {
 533                 result = SCTP_STRRESET_IN_PROGRESS;
 534                 goto err;
 535         }
 536
 537         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 538             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 539                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 540                 goto err;
 541         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 542                 i = asoc->strreset_inseq - request_seq - 1;
 543                 result = asoc->strreset_result[i];
 544                 goto err;
 545         }
 546         asoc->strreset_inseq++;
 547
 548         /* Check strreset_enable after inseq inc, as sender cannot tell
 549          * the peer doesn't enable strreset after receiving response with
 550          * result denied, as well as to keep consistent with bsd.
 551          */
 552         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
 553                 goto out;
 554
 555         nums = (ntohs(param.p->length) - sizeof(*outreq)) / sizeof(__u16);
 556         str_p = outreq->list_of_streams;
 557         for (i = 0; i < nums; i++) {
 558                 if (ntohs(str_p[i]) >= stream->incnt) {
 559                         result = SCTP_STRRESET_ERR_WRONG_SSN;
 560                         goto out;
 561                 }
 562         }
 563
 564         if (asoc->strreset_chunk) {
 565                 if (!sctp_chunk_lookup_strreset_param(
 566                                 asoc, outreq->response_seq,
 567                                 SCTP_PARAM_RESET_IN_REQUEST)) {
 568                         /* same process with outstanding isn't 0 */
 569                         result = SCTP_STRRESET_ERR_IN_PROGRESS;
 570                         goto out;
 571                 }
 572
 573                 asoc->strreset_outstanding--;
 574                 asoc->strreset_outseq++;
 575
 576                 if (!asoc->strreset_outstanding) {
 577                         struct sctp_transport *t;
 578
 579                         t = asoc->strreset_chunk->transport;
 580                         if (del_timer(&t->reconf_timer))
 581                                 sctp_transport_put(t);
 582
 583                         sctp_chunk_put(asoc->strreset_chunk);
 584                         asoc->strreset_chunk = NULL;
 585                 }
 586         }
 587
 588         if (nums)
 589                 for (i = 0; i < nums; i++)
 590                         SCTP_SI(stream, ntohs(str_p[i]))->mid = 0;
 591         else
 592                 for (i = 0; i < stream->incnt; i++)
 593                         SCTP_SI(stream, i)->mid = 0;
 594
 595         result = SCTP_STRRESET_PERFORMED;
 596
 597         *evp = sctp_ulpevent_make_stream_reset_event(asoc,
 598                 SCTP_STREAM_RESET_INCOMING_SSN, nums, str_p, GFP_ATOMIC);
 599
 600 out:
 601         sctp_update_strreset_result(asoc, result);
 602 err:
 603         return sctp_make_strreset_resp(asoc, result, request_seq);
 604 }
 605
 606 struct sctp_chunk *sctp_process_strreset_inreq(
 607                                 struct sctp_association *asoc,
 608                                 union sctp_params param,
 609                                 struct sctp_ulpevent **evp)
 610 {
 611         struct sctp_strreset_inreq *inreq = param.v;
 612         struct sctp_stream *stream = &asoc->stream;
 613         __u32 result = SCTP_STRRESET_DENIED;
 614         struct sctp_chunk *chunk = NULL;
 615         __u32 request_seq;
 616         __u16 i, nums;
 617         __be16 *str_p;
 618
 619         request_seq = ntohl(inreq->request_seq);
 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                 if (result == SCTP_STRRESET_PERFORMED)
 628                         return NULL;
 629                 goto err;
 630         }
 631         asoc->strreset_inseq++;
 632
 633         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
 634                 goto out;
 635
 636         if (asoc->strreset_outstanding) {
 637                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
 638                 goto out;
 639         }
 640
 641         nums = (ntohs(param.p->length) - sizeof(*inreq)) / sizeof(__u16);
 642         str_p = inreq->list_of_streams;
 643         for (i = 0; i < nums; i++) {
 644                 if (ntohs(str_p[i]) >= stream->outcnt) {
 645                         result = SCTP_STRRESET_ERR_WRONG_SSN;
 646                         goto out;
 647                 }
 648         }
 649
 650         if (!sctp_stream_outq_is_empty(stream, nums, str_p)) {
 651                 result = SCTP_STRRESET_IN_PROGRESS;
 652                 asoc->strreset_inseq--;
 653                 goto err;
 654         }
 655
 656         chunk = sctp_make_strreset_req(asoc, nums, str_p, 1, 0);
 657         if (!chunk)
 658                 goto out;
 659
 660         if (nums)
 661                 for (i = 0; i < nums; i++)
 662                         SCTP_SO(stream, ntohs(str_p[i]))->state =
 663                                                SCTP_STREAM_CLOSED;
 664         else
 665                 for (i = 0; i < stream->outcnt; i++)
 666                         SCTP_SO(stream, i)->state = SCTP_STREAM_CLOSED;
 667
 668         asoc->strreset_chunk = chunk;
 669         asoc->strreset_outstanding = 1;
 670         sctp_chunk_hold(asoc->strreset_chunk);
 671
 672         result = SCTP_STRRESET_PERFORMED;
 673
 674 out:
 675         sctp_update_strreset_result(asoc, result);
 676 err:
 677         if (!chunk)
 678                 chunk =  sctp_make_strreset_resp(asoc, result, request_seq);
 679
 680         return chunk;
 681 }
 682
 683 struct sctp_chunk *sctp_process_strreset_tsnreq(
 684                                 struct sctp_association *asoc,
 685                                 union sctp_params param,
 686                                 struct sctp_ulpevent **evp)
 687 {
 688         __u32 init_tsn = 0, next_tsn = 0, max_tsn_seen;
 689         struct sctp_strreset_tsnreq *tsnreq = param.v;
 690         struct sctp_stream *stream = &asoc->stream;
 691         __u32 result = SCTP_STRRESET_DENIED;
 692         __u32 request_seq;
 693         __u16 i;
 694
 695         request_seq = ntohl(tsnreq->request_seq);
 696         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 697             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 698                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 699                 goto err;
 700         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 701                 i = asoc->strreset_inseq - request_seq - 1;
 702                 result = asoc->strreset_result[i];
 703                 if (result == SCTP_STRRESET_PERFORMED) {
 704                         next_tsn = asoc->ctsn_ack_point + 1;
 705                         init_tsn =
 706                                 sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + 1;
 707                 }
 708                 goto err;
 709         }
 710
 711         if (!sctp_outq_is_empty(&asoc->outqueue)) {
 712                 result = SCTP_STRRESET_IN_PROGRESS;
 713                 goto err;
 714         }
 715
 716         asoc->strreset_inseq++;
 717
 718         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
 719                 goto out;
 720
 721         if (asoc->strreset_outstanding) {
 722                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
 723                 goto out;
 724         }
 725
 726         /* G4: The same processing as though a FWD-TSN chunk (as defined in
 727          *     [RFC3758]) with all streams affected and a new cumulative TSN
 728          *     ACK of the Receiver's Next TSN minus 1 were received MUST be
 729          *     performed.
 730          */
 731         max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
 732         asoc->stream.si->report_ftsn(&asoc->ulpq, max_tsn_seen);
 733
 734         /* G1: Compute an appropriate value for the Receiver's Next TSN -- the
 735          *     TSN that the peer should use to send the next DATA chunk.  The
 736          *     value SHOULD be the smallest TSN not acknowledged by the
 737          *     receiver of the request plus 2^31.
 738          */
 739         init_tsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + (1 << 31);
 740         sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
 741                          init_tsn, GFP_ATOMIC);
 742
 743         /* G3: The same processing as though a SACK chunk with no gap report
 744          *     and a cumulative TSN ACK of the Sender's Next TSN minus 1 were
 745          *     received MUST be performed.
 746          */
 747         sctp_outq_free(&asoc->outqueue);
 748
 749         /* G2: Compute an appropriate value for the local endpoint's next TSN,
 750          *     i.e., the next TSN assigned by the receiver of the SSN/TSN reset
 751          *     chunk.  The value SHOULD be the highest TSN sent by the receiver
 752          *     of the request plus 1.
 753          */
 754         next_tsn = asoc->next_tsn;
 755         asoc->ctsn_ack_point = next_tsn - 1;
 756         asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
 757
 758         /* G5:  The next expected and outgoing SSNs MUST be reset to 0 for all
 759          *      incoming and outgoing streams.
 760          */
 761         for (i = 0; i < stream->outcnt; i++) {
 762                 SCTP_SO(stream, i)->mid = 0;
 763                 SCTP_SO(stream, i)->mid_uo = 0;
 764         }
 765         for (i = 0; i < stream->incnt; i++)
 766                 SCTP_SI(stream, i)->mid = 0;
 767
 768         result = SCTP_STRRESET_PERFORMED;
 769
 770         *evp = sctp_ulpevent_make_assoc_reset_event(asoc, 0, init_tsn,
 771                                                     next_tsn, GFP_ATOMIC);
 772
 773 out:
 774         sctp_update_strreset_result(asoc, result);
 775 err:
 776         return sctp_make_strreset_tsnresp(asoc, result, request_seq,
 777                                           next_tsn, init_tsn);
 778 }
 779
 780 struct sctp_chunk *sctp_process_strreset_addstrm_out(
 781                                 struct sctp_association *asoc,
 782                                 union sctp_params param,
 783                                 struct sctp_ulpevent **evp)
 784 {
 785         struct sctp_strreset_addstrm *addstrm = param.v;
 786         struct sctp_stream *stream = &asoc->stream;
 787         __u32 result = SCTP_STRRESET_DENIED;
 788         __u32 request_seq, incnt;
 789         __u16 in, i;
 790
 791         request_seq = ntohl(addstrm->request_seq);
 792         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 793             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 794                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 795                 goto err;
 796         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 797                 i = asoc->strreset_inseq - request_seq - 1;
 798                 result = asoc->strreset_result[i];
 799                 goto err;
 800         }
 801         asoc->strreset_inseq++;
 802
 803         if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
 804                 goto out;
 805
 806         in = ntohs(addstrm->number_of_streams);
 807         incnt = stream->incnt + in;
 808         if (!in || incnt > SCTP_MAX_STREAM)
 809                 goto out;
 810
 811         if (sctp_stream_alloc_in(stream, incnt, GFP_ATOMIC))
 812                 goto out;
 813
 814         if (asoc->strreset_chunk) {
 815                 if (!sctp_chunk_lookup_strreset_param(
 816                         asoc, 0, SCTP_PARAM_RESET_ADD_IN_STREAMS)) {
 817                         /* same process with outstanding isn't 0 */
 818                         result = SCTP_STRRESET_ERR_IN_PROGRESS;
 819                         goto out;
 820                 }
 821
 822                 asoc->strreset_outstanding--;
 823                 asoc->strreset_outseq++;
 824
 825                 if (!asoc->strreset_outstanding) {
 826                         struct sctp_transport *t;
 827
 828                         t = asoc->strreset_chunk->transport;
 829                         if (del_timer(&t->reconf_timer))
 830                                 sctp_transport_put(t);
 831
 832                         sctp_chunk_put(asoc->strreset_chunk);
 833                         asoc->strreset_chunk = NULL;
 834                 }
 835         }
 836
 837         stream->incnt = incnt;
 838
 839         result = SCTP_STRRESET_PERFORMED;
 840
 841         *evp = sctp_ulpevent_make_stream_change_event(asoc,
 842                 0, ntohs(addstrm->number_of_streams), 0, GFP_ATOMIC);
 843
 844 out:
 845         sctp_update_strreset_result(asoc, result);
 846 err:
 847         return sctp_make_strreset_resp(asoc, result, request_seq);
 848 }
 849
 850 struct sctp_chunk *sctp_process_strreset_addstrm_in(
 851                                 struct sctp_association *asoc,
 852                                 union sctp_params param,
 853                                 struct sctp_ulpevent **evp)
 854 {
 855         struct sctp_strreset_addstrm *addstrm = param.v;
 856         struct sctp_stream *stream = &asoc->stream;
 857         __u32 result = SCTP_STRRESET_DENIED;
 858         struct sctp_chunk *chunk = NULL;
 859         __u32 request_seq, outcnt;
 860         __u16 out, i;
 861         int ret;
 862
 863         request_seq = ntohl(addstrm->request_seq);
 864         if (TSN_lt(asoc->strreset_inseq, request_seq) ||
 865             TSN_lt(request_seq, asoc->strreset_inseq - 2)) {
 866                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 867                 goto err;
 868         } else if (TSN_lt(request_seq, asoc->strreset_inseq)) {
 869                 i = asoc->strreset_inseq - request_seq - 1;
 870                 result = asoc->strreset_result[i];
 871                 if (result == SCTP_STRRESET_PERFORMED)
 872                         return NULL;
 873                 goto err;
 874         }
 875         asoc->strreset_inseq++;
 876
 877         if (!(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ))
 878                 goto out;
 879
 880         if (asoc->strreset_outstanding) {
 881                 result = SCTP_STRRESET_ERR_IN_PROGRESS;
 882                 goto out;
 883         }
 884
 885         out = ntohs(addstrm->number_of_streams);
 886         outcnt = stream->outcnt + out;
 887         if (!out || outcnt > SCTP_MAX_STREAM)
 888                 goto out;
 889
 890         ret = sctp_stream_alloc_out(stream, outcnt, GFP_ATOMIC);
 891         if (ret)
 892                 goto out;
 893
 894         chunk = sctp_make_strreset_addstrm(asoc, out, 0);
 895         if (!chunk)
 896                 goto out;
 897
 898         asoc->strreset_chunk = chunk;
 899         asoc->strreset_outstanding = 1;
 900         sctp_chunk_hold(asoc->strreset_chunk);
 901
 902         stream->outcnt = outcnt;
 903
 904         result = SCTP_STRRESET_PERFORMED;
 905
 906 out:
 907         sctp_update_strreset_result(asoc, result);
 908 err:
 909         if (!chunk)
 910                 chunk = sctp_make_strreset_resp(asoc, result, request_seq);
 911
 912         return chunk;
 913 }
 914
 915 struct sctp_chunk *sctp_process_strreset_resp(
 916                                 struct sctp_association *asoc,
 917                                 union sctp_params param,
 918                                 struct sctp_ulpevent **evp)
 919 {
 920         struct sctp_stream *stream = &asoc->stream;
 921         struct sctp_strreset_resp *resp = param.v;
 922         struct sctp_transport *t;
 923         __u16 i, nums, flags = 0;
 924         struct sctp_paramhdr *req;
 925         __u32 result;
 926
 927         req = sctp_chunk_lookup_strreset_param(asoc, resp->response_seq, 0);
 928         if (!req)
 929                 return NULL;
 930
 931         result = ntohl(resp->result);
 932         if (result != SCTP_STRRESET_PERFORMED) {
 933                 /* if in progress, do nothing but retransmit */
 934                 if (result == SCTP_STRRESET_IN_PROGRESS)
 935                         return NULL;
 936                 else if (result == SCTP_STRRESET_DENIED)
 937                         flags = SCTP_STREAM_RESET_DENIED;
 938                 else
 939                         flags = SCTP_STREAM_RESET_FAILED;
 940         }
 941
 942         if (req->type == SCTP_PARAM_RESET_OUT_REQUEST) {
 943                 struct sctp_strreset_outreq *outreq;
 944                 __be16 *str_p;
 945
 946                 outreq = (struct sctp_strreset_outreq *)req;
 947                 str_p = outreq->list_of_streams;
 948                 nums = (ntohs(outreq->param_hdr.length) - sizeof(*outreq)) /
 949                        sizeof(__u16);
 950
 951                 if (result == SCTP_STRRESET_PERFORMED) {
 952                         struct sctp_stream_out *sout;
 953                         if (nums) {
 954                                 for (i = 0; i < nums; i++) {
 955                                         sout = SCTP_SO(stream, ntohs(str_p[i]));
 956                                         sout->mid = 0;
 957                                         sout->mid_uo = 0;
 958                                 }
 959                         } else {
 960                                 for (i = 0; i < stream->outcnt; i++) {
 961                                         sout = SCTP_SO(stream, i);
 962                                         sout->mid = 0;
 963                                         sout->mid_uo = 0;
 964                                 }
 965                         }
 966                 }
 967
 968                 flags |= SCTP_STREAM_RESET_OUTGOING_SSN;
 969
 970                 for (i = 0; i < stream->outcnt; i++)
 971                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
 972
 973                 *evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
 974                         nums, str_p, GFP_ATOMIC);
 975         } else if (req->type == SCTP_PARAM_RESET_IN_REQUEST) {
 976                 struct sctp_strreset_inreq *inreq;
 977                 __be16 *str_p;
 978
 979                 /* if the result is performed, it's impossible for inreq */
 980                 if (result == SCTP_STRRESET_PERFORMED)
 981                         return NULL;
 982
 983                 inreq = (struct sctp_strreset_inreq *)req;
 984                 str_p = inreq->list_of_streams;
 985                 nums = (ntohs(inreq->param_hdr.length) - sizeof(*inreq)) /
 986                        sizeof(__u16);
 987
 988                 flags |= SCTP_STREAM_RESET_INCOMING_SSN;
 989
 990                 *evp = sctp_ulpevent_make_stream_reset_event(asoc, flags,
 991                         nums, str_p, GFP_ATOMIC);
 992         } else if (req->type == SCTP_PARAM_RESET_TSN_REQUEST) {
 993                 struct sctp_strreset_resptsn *resptsn;
 994                 __u32 stsn, rtsn;
 995
 996                 /* check for resptsn, as sctp_verify_reconf didn't do it*/
 997                 if (ntohs(param.p->length) != sizeof(*resptsn))
 998                         return NULL;
 999
1000                 resptsn = (struct sctp_strreset_resptsn *)resp;
1001                 stsn = ntohl(resptsn->senders_next_tsn);
1002                 rtsn = ntohl(resptsn->receivers_next_tsn);
1003
1004                 if (result == SCTP_STRRESET_PERFORMED) {
1005                         __u32 mtsn = sctp_tsnmap_get_max_tsn_seen(
1006                                                 &asoc->peer.tsn_map);
1007                         LIST_HEAD(temp);
1008
1009                         asoc->stream.si->report_ftsn(&asoc->ulpq, mtsn);
1010
1011                         sctp_tsnmap_init(&asoc->peer.tsn_map,
1012                                          SCTP_TSN_MAP_INITIAL,
1013                                          stsn, GFP_ATOMIC);
1014
1015                         /* Clean up sacked and abandoned queues only. As the
1016                          * out_chunk_list may not be empty, splice it to temp,
1017                          * then get it back after sctp_outq_free is done.
1018                          */
1019                         list_splice_init(&asoc->outqueue.out_chunk_list, &temp);
1020                         sctp_outq_free(&asoc->outqueue);
1021                         list_splice_init(&temp, &asoc->outqueue.out_chunk_list);
1022
1023                         asoc->next_tsn = rtsn;
1024                         asoc->ctsn_ack_point = asoc->next_tsn - 1;
1025                         asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
1026
1027                         for (i = 0; i < stream->outcnt; i++) {
1028                                 SCTP_SO(stream, i)->mid = 0;
1029                                 SCTP_SO(stream, i)->mid_uo = 0;
1030                         }
1031                         for (i = 0; i < stream->incnt; i++)
1032                                 SCTP_SI(stream, i)->mid = 0;
1033                 }
1034
1035                 for (i = 0; i < stream->outcnt; i++)
1036                         SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
1037
1038                 *evp = sctp_ulpevent_make_assoc_reset_event(asoc, flags,
1039                         stsn, rtsn, GFP_ATOMIC);
1040         } else if (req->type == SCTP_PARAM_RESET_ADD_OUT_STREAMS) {
1041                 struct sctp_strreset_addstrm *addstrm;
1042                 __u16 number;
1043
1044                 addstrm = (struct sctp_strreset_addstrm *)req;
1045                 nums = ntohs(addstrm->number_of_streams);
1046                 number = stream->outcnt - nums;
1047
1048                 if (result == SCTP_STRRESET_PERFORMED) {
1049                         for (i = number; i < stream->outcnt; i++)
1050                                 SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
1051                 } else {
1052                         sctp_stream_shrink_out(stream, number);
1053                         stream->outcnt = number;
1054                 }
1055
1056                 *evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1057                         0, nums, GFP_ATOMIC);
1058         } else if (req->type == SCTP_PARAM_RESET_ADD_IN_STREAMS) {
1059                 struct sctp_strreset_addstrm *addstrm;
1060
1061                 /* if the result is performed, it's impossible for addstrm in
1062                  * request.
1063                  */
1064                 if (result == SCTP_STRRESET_PERFORMED)
1065                         return NULL;
1066
1067                 addstrm = (struct sctp_strreset_addstrm *)req;
1068                 nums = ntohs(addstrm->number_of_streams);
1069
1070                 *evp = sctp_ulpevent_make_stream_change_event(asoc, flags,
1071                         nums, 0, GFP_ATOMIC);
1072         }
1073
1074         asoc->strreset_outstanding--;
1075         asoc->strreset_outseq++;
1076
1077         /* remove everything for this reconf request */
1078         if (!asoc->strreset_outstanding) {
1079                 t = asoc->strreset_chunk->transport;
1080                 if (del_timer(&t->reconf_timer))
1081                         sctp_transport_put(t);
1082
1083                 sctp_chunk_put(asoc->strreset_chunk);
1084                 asoc->strreset_chunk = NULL;
1085         }
1086
1087         return NULL;
1088 }