net/sctp/stream.c

   1 /* SCTP kernel implementation
   2  * (C) Copyright IBM Corp. 2001, 2004
   3  * Copyright (c) 1999-2000 Cisco, Inc.
   4  * Copyright (c) 1999-2001 Motorola, Inc.
   5  * Copyright (c) 2001 Intel Corp.
   6  *
   7  * This file is part of the SCTP kernel implementation
   8  *
   9  * These functions manipulate sctp tsn mapping array.
  10  *
  11  * This SCTP implementation is free software;
  12  * you can redistribute it and/or modify it under the terms of
  13  * the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2, or (at your option)
  15  * any later version.
  16  *
  17  * This SCTP implementation is distributed in the hope that it
  18  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  19  *                 ************************
  20  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  21  * See the GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with GNU CC; see the file COPYING.  If not, see
  25  * <http://www.gnu.org/licenses/>.
  26  *
  27  * Please send any bug reports or fixes you make to the
  28  * email address(es):
  29  *    lksctp developers <linux-sctp@vger.kernel.org>
  30  *
  31  * Written or modified by:
  32  *    Xin Long <lucien.xin@gmail.com>
  33  */
  34
  35 #include <net/sctp/sctp.h>
  36 #include <net/sctp/sm.h>
  37
  38 struct sctp_stream *sctp_stream_new(__u16 incnt, __u16 outcnt, gfp_t gfp)
  39 {
  40         struct sctp_stream *stream;
  41         int i;
  42
  43         stream = kzalloc(sizeof(*stream), gfp);
  44         if (!stream)
  45                 return NULL;
  46
  47         stream->outcnt = outcnt;
  48         stream->out = kcalloc(stream->outcnt, sizeof(*stream->out), gfp);
  49         if (!stream->out) {
  50                 kfree(stream);
  51                 return NULL;
  52         }
  53         for (i = 0; i < stream->outcnt; i++)
  54                 stream->out[i].state = SCTP_STREAM_OPEN;
  55
  56         stream->incnt = incnt;
  57         stream->in = kcalloc(stream->incnt, sizeof(*stream->in), gfp);
  58         if (!stream->in) {
  59                 kfree(stream->out);
  60                 kfree(stream);
  61                 return NULL;
  62         }
  63
  64         return stream;
  65 }
  66
  67 void sctp_stream_free(struct sctp_stream *stream)
  68 {
  69         if (unlikely(!stream))
  70                 return;
  71
  72         kfree(stream->out);
  73         kfree(stream->in);
  74         kfree(stream);
  75 }
  76
  77 void sctp_stream_clear(struct sctp_stream *stream)
  78 {
  79         int i;
  80
  81         for (i = 0; i < stream->outcnt; i++)
  82                 stream->out[i].ssn = 0;
  83
  84         for (i = 0; i < stream->incnt; i++)
  85                 stream->in[i].ssn = 0;
  86 }
  87
  88 static int sctp_send_reconf(struct sctp_association *asoc,
  89                             struct sctp_chunk *chunk)
  90 {
  91         struct net *net = sock_net(asoc->base.sk);
  92         int retval = 0;
  93
  94         retval = sctp_primitive_RECONF(net, asoc, chunk);
  95         if (retval)
  96                 sctp_chunk_free(chunk);
  97
  98         return retval;
  99 }
 100
 101 int sctp_send_reset_streams(struct sctp_association *asoc,
 102                             struct sctp_reset_streams *params)
 103 {
 104         struct sctp_stream *stream = asoc->stream;
 105         __u16 i, str_nums, *str_list;
 106         struct sctp_chunk *chunk;
 107         int retval = -EINVAL;
 108         bool out, in;
 109
 110         if (!asoc->peer.reconf_capable ||
 111             !(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ)) {
 112                 retval = -ENOPROTOOPT;
 113                 goto out;
 114         }
 115
 116         if (asoc->strreset_outstanding) {
 117                 retval = -EINPROGRESS;
 118                 goto out;
 119         }
 120
 121         out = params->srs_flags & SCTP_STREAM_RESET_OUTGOING;
 122         in  = params->srs_flags & SCTP_STREAM_RESET_INCOMING;
 123         if (!out && !in)
 124                 goto out;
 125
 126         str_nums = params->srs_number_streams;
 127         str_list = params->srs_stream_list;
 128         if (out && str_nums)
 129                 for (i = 0; i < str_nums; i++)
 130                         if (str_list[i] >= stream->outcnt)
 131                                 goto out;
 132
 133         if (in && str_nums)
 134                 for (i = 0; i < str_nums; i++)
 135                         if (str_list[i] >= stream->incnt)
 136                                 goto out;
 137
 138         chunk = sctp_make_strreset_req(asoc, str_nums, str_list, out, in);
 139         if (!chunk) {
 140                 retval = -ENOMEM;
 141                 goto out;
 142         }
 143
 144         if (out) {
 145                 if (str_nums)
 146                         for (i = 0; i < str_nums; i++)
 147                                 stream->out[str_list[i]].state =
 148                                                        SCTP_STREAM_CLOSED;
 149                 else
 150                         for (i = 0; i < stream->outcnt; i++)
 151                                 stream->out[i].state = SCTP_STREAM_CLOSED;
 152         }
 153
 154         asoc->strreset_chunk = chunk;
 155         sctp_chunk_hold(asoc->strreset_chunk);
 156
 157         retval = sctp_send_reconf(asoc, chunk);
 158         if (retval) {
 159                 sctp_chunk_put(asoc->strreset_chunk);
 160                 asoc->strreset_chunk = NULL;
 161                 if (!out)
 162                         goto out;
 163
 164                 if (str_nums)
 165                         for (i = 0; i < str_nums; i++)
 166                                 stream->out[str_list[i]].state =
 167                                                        SCTP_STREAM_OPEN;
 168                 else
 169                         for (i = 0; i < stream->outcnt; i++)
 170                                 stream->out[i].state = SCTP_STREAM_OPEN;
 171
 172                 goto out;
 173         }
 174
 175         asoc->strreset_outstanding = out + in;
 176
 177 out:
 178         return retval;
 179 }
 180
 181 int sctp_send_reset_assoc(struct sctp_association *asoc)
 182 {
 183         struct sctp_chunk *chunk = NULL;
 184         int retval;
 185         __u16 i;
 186
 187         if (!asoc->peer.reconf_capable ||
 188             !(asoc->strreset_enable & SCTP_ENABLE_RESET_ASSOC_REQ))
 189                 return -ENOPROTOOPT;
 190
 191         if (asoc->strreset_outstanding)
 192                 return -EINPROGRESS;
 193
 194         chunk = sctp_make_strreset_tsnreq(asoc);
 195         if (!chunk)
 196                 return -ENOMEM;
 197
 198         /* Block further xmit of data until this request is completed */
 199         for (i = 0; i < asoc->stream->outcnt; i++)
 200                 asoc->stream->out[i].state = SCTP_STREAM_CLOSED;
 201
 202         asoc->strreset_chunk = chunk;
 203         sctp_chunk_hold(asoc->strreset_chunk);
 204
 205         retval = sctp_send_reconf(asoc, chunk);
 206         if (retval) {
 207                 sctp_chunk_put(asoc->strreset_chunk);
 208                 asoc->strreset_chunk = NULL;
 209
 210                 for (i = 0; i < asoc->stream->outcnt; i++)
 211                         asoc->stream->out[i].state = SCTP_STREAM_OPEN;
 212
 213                 return retval;
 214         }
 215
 216         asoc->strreset_outstanding = 1;
 217
 218         return 0;
 219 }
 220
 221 int sctp_send_add_streams(struct sctp_association *asoc,
 222                           struct sctp_add_streams *params)
 223 {
 224         struct sctp_stream *stream = asoc->stream;
 225         struct sctp_chunk *chunk = NULL;
 226         int retval = -ENOMEM;
 227         __u32 outcnt, incnt;
 228         __u16 out, in;
 229
 230         if (!asoc->peer.reconf_capable ||
 231             !(asoc->strreset_enable & SCTP_ENABLE_CHANGE_ASSOC_REQ)) {
 232                 retval = -ENOPROTOOPT;
 233                 goto out;
 234         }
 235
 236         if (asoc->strreset_outstanding) {
 237                 retval = -EINPROGRESS;
 238                 goto out;
 239         }
 240
 241         out = params->sas_outstrms;
 242         in  = params->sas_instrms;
 243         outcnt = stream->outcnt + out;
 244         incnt = stream->incnt + in;
 245         if (outcnt > SCTP_MAX_STREAM || incnt > SCTP_MAX_STREAM ||
 246             (!out && !in)) {
 247                 retval = -EINVAL;
 248                 goto out;
 249         }
 250
 251         if (out) {
 252                 struct sctp_stream_out *streamout;
 253
 254                 streamout = krealloc(stream->out, outcnt * sizeof(*streamout),
 255                                      GFP_KERNEL);
 256                 if (!streamout)
 257                         goto out;
 258
 259                 memset(streamout + stream->outcnt, 0, out * sizeof(*streamout));
 260                 stream->out = streamout;
 261         }
 262
 263         if (in) {
 264                 struct sctp_stream_in *streamin;
 265
 266                 streamin = krealloc(stream->in, incnt * sizeof(*streamin),
 267                                     GFP_KERNEL);
 268                 if (!streamin)
 269                         goto out;
 270
 271                 memset(streamin + stream->incnt, 0, in * sizeof(*streamin));
 272                 stream->in = streamin;
 273         }
 274
 275         chunk = sctp_make_strreset_addstrm(asoc, out, in);
 276         if (!chunk)
 277                 goto out;
 278
 279         asoc->strreset_chunk = chunk;
 280         sctp_chunk_hold(asoc->strreset_chunk);
 281
 282         retval = sctp_send_reconf(asoc, chunk);
 283         if (retval) {
 284                 sctp_chunk_put(asoc->strreset_chunk);
 285                 asoc->strreset_chunk = NULL;
 286                 goto out;
 287         }
 288
 289         stream->incnt = incnt;
 290         stream->outcnt = outcnt;
 291
 292         asoc->strreset_outstanding = !!out + !!in;
 293
 294 out:
 295         return retval;
 296 }
 297
 298 static sctp_paramhdr_t *sctp_chunk_lookup_strreset_param(
 299                         struct sctp_association *asoc, __u32 resp_seq)
 300 {
 301         struct sctp_chunk *chunk = asoc->strreset_chunk;
 302         struct sctp_reconf_chunk *hdr;
 303         union sctp_params param;
 304
 305         if (ntohl(resp_seq) != asoc->strreset_outseq || !chunk)
 306                 return NULL;
 307
 308         hdr = (struct sctp_reconf_chunk *)chunk->chunk_hdr;
 309         sctp_walk_params(param, hdr, params) {
 310                 /* sctp_strreset_tsnreq is actually the basic structure
 311                  * of all stream reconf params, so it's safe to use it
 312                  * to access request_seq.
 313                  */
 314                 struct sctp_strreset_tsnreq *req = param.v;
 315
 316                 if (req->request_seq == resp_seq)
 317                         return param.v;
 318         }
 319
 320         return NULL;
 321 }
 322
 323 struct sctp_chunk *sctp_process_strreset_outreq(
 324                                 struct sctp_association *asoc,
 325                                 union sctp_params param,
 326                                 struct sctp_ulpevent **evp)
 327 {
 328         struct sctp_strreset_outreq *outreq = param.v;
 329         struct sctp_stream *stream = asoc->stream;
 330         __u16 i, nums, flags = 0, *str_p = NULL;
 331         __u32 result = SCTP_STRRESET_DENIED;
 332         __u32 request_seq;
 333
 334         request_seq = ntohl(outreq->request_seq);
 335
 336         if (ntohl(outreq->send_reset_at_tsn) >
 337             sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map)) {
 338                 result = SCTP_STRRESET_IN_PROGRESS;
 339                 goto out;
 340         }
 341
 342         if (request_seq > asoc->strreset_inseq) {
 343                 result = SCTP_STRRESET_ERR_BAD_SEQNO;
 344                 goto out;
 345         } else if (request_seq == asoc->strreset_inseq) {
 346                 asoc->strreset_inseq++;
 347         }
 348
 349         /* Check strreset_enable after inseq inc, as sender cannot tell
 350          * the peer doesn't enable strreset after receiving response with
 351          * result denied, as well as to keep consistent with bsd.
 352          */
 353         if (!(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ))
 354                 goto out;
 355
 356         if (asoc->strreset_chunk) {
 357                 sctp_paramhdr_t *param_hdr;
 358                 struct sctp_transport *t;
 359
 360                 param_hdr = sctp_chunk_lookup_strreset_param(
 361                                         asoc, outreq->response_seq);
 362                 if (!param_hdr || param_hdr->type !=
 363                                         SCTP_PARAM_RESET_IN_REQUEST) {
 364                         /* same process with outstanding isn't 0 */
 365                         result = SCTP_STRRESET_ERR_IN_PROGRESS;
 366                         goto out;
 367                 }
 368
 369                 asoc->strreset_outstanding--;
 370                 asoc->strreset_outseq++;
 371
 372                 if (!asoc->strreset_outstanding) {
 373                         t = asoc->strreset_chunk->transport;
 374                         if (del_timer(&t->reconf_timer))
 375                                 sctp_transport_put(t);
 376
 377                         sctp_chunk_put(asoc->strreset_chunk);
 378                         asoc->strreset_chunk = NULL;
 379                 }
 380
 381                 flags = SCTP_STREAM_RESET_INCOMING_SSN;
 382         }
 383
 384         nums = (ntohs(param.p->length) - sizeof(*outreq)) / 2;
 385         if (nums) {
 386                 str_p = outreq->list_of_streams;
 387                 for (i = 0; i < nums; i++) {
 388                         if (ntohs(str_p[i]) >= stream->incnt) {
 389                                 result = SCTP_STRRESET_ERR_WRONG_SSN;
 390                                 goto out;
 391                         }
 392                 }
 393
 394                 for (i = 0; i < nums; i++)
 395                         stream->in[ntohs(str_p[i])].ssn = 0;
 396         } else {
 397                 for (i = 0; i < stream->incnt; i++)
 398                         stream->in[i].ssn = 0;
 399         }
 400
 401         result = SCTP_STRRESET_PERFORMED;
 402
 403         *evp = sctp_ulpevent_make_stream_reset_event(asoc,
 404                 flags | SCTP_STREAM_RESET_OUTGOING_SSN, nums, str_p,
 405                 GFP_ATOMIC);
 406
 407 out:
 408         return sctp_make_strreset_resp(asoc, result, request_seq);
 409 }