net/sctp/sm_sideeffect.c

   1 /* SCTP kernel reference Implementation
   2  * (C) Copyright IBM Corp. 2001, 2004
   3  * Copyright (c) 1999 Cisco, Inc.
   4  * Copyright (c) 1999-2001 Motorola, Inc.
   5  *
   6  * This file is part of the SCTP kernel reference Implementation
   7  *
   8  * These functions work with the state functions in sctp_sm_statefuns.c
   9  * to implement that state operations.  These functions implement the
  10  * steps which require modifying existing data structures.
  11  *
  12  * The SCTP reference implementation is free software;
  13  * you can redistribute it and/or modify it under the terms of
  14  * the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2, or (at your option)
  16  * any later version.
  17  *
  18  * The SCTP reference implementation is distributed in the hope that it
  19  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  20  *                 ************************
  21  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  22  * See the GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with GNU CC; see the file COPYING.  If not, write to
  26  * the Free Software Foundation, 59 Temple Place - Suite 330,
  27  * Boston, MA 02111-1307, USA.
  28  *
  29  * Please send any bug reports or fixes you make to the
  30  * email address(es):
  31  *    lksctp developers <lksctp-developers@lists.sourceforge.net>
  32  *
  33  * Or submit a bug report through the following website:
  34  *    http://www.sf.net/projects/lksctp
  35  *
  36  * Written or modified by:
  37  *    La Monte H.P. Yarroll <piggy@acm.org>
  38  *    Karl Knutson          <karl@athena.chicago.il.us>
  39  *    Jon Grimm             <jgrimm@austin.ibm.com>
  40  *    Hui Huang             <hui.huang@nokia.com>
  41  *    Dajiang Zhang         <dajiang.zhang@nokia.com>
  42  *    Daisy Chang           <daisyc@us.ibm.com>
  43  *    Sridhar Samudrala     <sri@us.ibm.com>
  44  *    Ardelle Fan           <ardelle.fan@intel.com>
  45  *
  46  * Any bugs reported given to us we will try to fix... any fixes shared will
  47  * be incorporated into the next SCTP release.
  48  */
  49
  50 #include <linux/skbuff.h>
  51 #include <linux/types.h>
  52 #include <linux/socket.h>
  53 #include <linux/ip.h>
  54 #include <net/sock.h>
  55 #include <net/sctp/sctp.h>
  56 #include <net/sctp/sm.h>
  57
  58 /********************************************************************
  59  * Helper functions
  60  ********************************************************************/
  61
  62 /* A helper function for delayed processing of INET ECN CE bit. */
  63 static void sctp_do_ecn_ce_work(struct sctp_association *asoc,
  64                                 __u32 lowest_tsn)
  65 {
  66         /* Save the TSN away for comparison when we receive CWR */
  67
  68         asoc->last_ecne_tsn = lowest_tsn;
  69         asoc->need_ecne = 1;
  70 }
  71
  72 /* Helper function for delayed processing of SCTP ECNE chunk.  */
  73 /* RFC 2960 Appendix A
  74  *
  75  * RFC 2481 details a specific bit for a sender to send in
  76  * the header of its next outbound TCP segment to indicate to
  77  * its peer that it has reduced its congestion window.  This
  78  * is termed the CWR bit.  For SCTP the same indication is made
  79  * by including the CWR chunk.  This chunk contains one data
  80  * element, i.e. the TSN number that was sent in the ECNE chunk.
  81  * This element represents the lowest TSN number in the datagram
  82  * that was originally marked with the CE bit.
  83  */
  84 static struct sctp_chunk *sctp_do_ecn_ecne_work(struct sctp_association *asoc,
  85                                            __u32 lowest_tsn,
  86                                            struct sctp_chunk *chunk)
  87 {
  88         struct sctp_chunk *repl;
  89
  90         /* Our previously transmitted packet ran into some congestion
  91          * so we should take action by reducing cwnd and ssthresh
  92          * and then ACK our peer that we we've done so by
  93          * sending a CWR.
  94          */
  95
  96         /* First, try to determine if we want to actually lower
  97          * our cwnd variables.  Only lower them if the ECNE looks more
  98          * recent than the last response.
  99          */
 100         if (TSN_lt(asoc->last_cwr_tsn, lowest_tsn)) {
 101                 struct sctp_transport *transport;
 102
 103                 /* Find which transport's congestion variables
 104                  * need to be adjusted.
 105                  */
 106                 transport = sctp_assoc_lookup_tsn(asoc, lowest_tsn);
 107
 108                 /* Update the congestion variables. */
 109                 if (transport)
 110                         sctp_transport_lower_cwnd(transport,
 111                                                   SCTP_LOWER_CWND_ECNE);
 112                 asoc->last_cwr_tsn = lowest_tsn;
 113         }
 114
 115         /* Always try to quiet the other end.  In case of lost CWR,
 116          * resend last_cwr_tsn.
 117          */
 118         repl = sctp_make_cwr(asoc, asoc->last_cwr_tsn, chunk);
 119
 120         /* If we run out of memory, it will look like a lost CWR.  We'll
 121          * get back in sync eventually.
 122          */
 123         return repl;
 124 }
 125
 126 /* Helper function to do delayed processing of ECN CWR chunk.  */
 127 static void sctp_do_ecn_cwr_work(struct sctp_association *asoc,
 128                                  __u32 lowest_tsn)
 129 {
 130         /* Turn off ECNE getting auto-prepended to every outgoing
 131          * packet
 132          */
 133         asoc->need_ecne = 0;
 134 }
 135
 136 /* Generate SACK if necessary.  We call this at the end of a packet.  */
 137 int sctp_gen_sack(struct sctp_association *asoc, int force,
 138                   sctp_cmd_seq_t *commands)
 139 {
 140         __u32 ctsn, max_tsn_seen;
 141         struct sctp_chunk *sack;
 142         int error = 0;
 143
 144         if (force)
 145                 asoc->peer.sack_needed = 1;
 146
 147         ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
 148         max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
 149
 150         /* From 12.2 Parameters necessary per association (i.e. the TCB):
 151          *
 152          * Ack State : This flag indicates if the next received packet
 153          *           : is to be responded to with a SACK. ...
 154          *           : When DATA chunks are out of order, SACK's
 155          *           : are not delayed (see Section 6).
 156          *
 157          * [This is actually not mentioned in Section 6, but we
 158          * implement it here anyway. --piggy]
 159          */
 160         if (max_tsn_seen != ctsn)
 161                 asoc->peer.sack_needed = 1;
 162
 163         /* From 6.2  Acknowledgement on Reception of DATA Chunks:
 164          *
 165          * Section 4.2 of [RFC2581] SHOULD be followed. Specifically,
 166          * an acknowledgement SHOULD be generated for at least every
 167          * second packet (not every second DATA chunk) received, and
 168          * SHOULD be generated within 200 ms of the arrival of any
 169          * unacknowledged DATA chunk. ...
 170          */
 171         if (!asoc->peer.sack_needed) {
 172                 /* We will need a SACK for the next packet.  */
 173                 asoc->peer.sack_needed = 1;
 174                 goto out;
 175         } else {
 176                 if (asoc->a_rwnd > asoc->rwnd)
 177                         asoc->a_rwnd = asoc->rwnd;
 178                 sack = sctp_make_sack(asoc);
 179                 if (!sack)
 180                         goto nomem;
 181
 182                 asoc->peer.sack_needed = 0;
 183
 184                 error = sctp_outq_tail(&asoc->outqueue, sack);
 185
 186                 /* Stop the SACK timer.  */
 187                 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
 188                                 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
 189         }
 190 out:
 191         return error;
 192 nomem:
 193         error = -ENOMEM;
 194         return error;
 195 }
 196
 197 /* When the T3-RTX timer expires, it calls this function to create the
 198  * relevant state machine event.
 199  */
 200 void sctp_generate_t3_rtx_event(unsigned long peer)
 201 {
 202         int error;
 203         struct sctp_transport *transport = (struct sctp_transport *) peer;
 204         struct sctp_association *asoc = transport->asoc;
 205
 206         /* Check whether a task is in the sock.  */
 207
 208         sctp_bh_lock_sock(asoc->base.sk);
 209         if (sock_owned_by_user(asoc->base.sk)) {
 210                 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __FUNCTION__);
 211
 212                 /* Try again later.  */
 213                 if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20)))
 214                         sctp_transport_hold(transport);
 215                 goto out_unlock;
 216         }
 217
 218         /* Is this transport really dead and just waiting around for
 219          * the timer to let go of the reference?
 220          */
 221         if (transport->dead)
 222                 goto out_unlock;
 223
 224         /* Run through the state machine.  */
 225         error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
 226                            SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX),
 227                            asoc->state,
 228                            asoc->ep, asoc,
 229                            transport, GFP_ATOMIC);
 230
 231         if (error)
 232                 asoc->base.sk->sk_err = -error;
 233
 234 out_unlock:
 235         sctp_bh_unlock_sock(asoc->base.sk);
 236         sctp_transport_put(transport);
 237 }
 238
 239 /* This is a sa interface for producing timeout events.  It works
 240  * for timeouts which use the association as their parameter.
 241  */
 242 static void sctp_generate_timeout_event(struct sctp_association *asoc,
 243                                         sctp_event_timeout_t timeout_type)
 244 {
 245         int error = 0;
 246
 247         sctp_bh_lock_sock(asoc->base.sk);
 248         if (sock_owned_by_user(asoc->base.sk)) {
 249                 SCTP_DEBUG_PRINTK("%s:Sock is busy: timer %d\n",
 250                                   __FUNCTION__,
 251                                   timeout_type);
 252
 253                 /* Try again later.  */
 254                 if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20)))
 255                         sctp_association_hold(asoc);
 256                 goto out_unlock;
 257         }
 258
 259         /* Is this association really dead and just waiting around for
 260          * the timer to let go of the reference?
 261          */
 262         if (asoc->base.dead)
 263                 goto out_unlock;
 264
 265         /* Run through the state machine.  */
 266         error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
 267                            SCTP_ST_TIMEOUT(timeout_type),
 268                            asoc->state, asoc->ep, asoc,
 269                            (void *)timeout_type, GFP_ATOMIC);
 270
 271         if (error)
 272                 asoc->base.sk->sk_err = -error;
 273
 274 out_unlock:
 275         sctp_bh_unlock_sock(asoc->base.sk);
 276         sctp_association_put(asoc);
 277 }
 278
 279 void sctp_generate_t1_cookie_event(unsigned long data)
 280 {
 281         struct sctp_association *asoc = (struct sctp_association *) data;
 282         sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE);
 283 }
 284
 285 void sctp_generate_t1_init_event(unsigned long data)
 286 {
 287         struct sctp_association *asoc = (struct sctp_association *) data;
 288         sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT);
 289 }
 290
 291 void sctp_generate_t2_shutdown_event(unsigned long data)
 292 {
 293         struct sctp_association *asoc = (struct sctp_association *) data;
 294         sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN);
 295 }
 296
 297 void sctp_generate_t4_rto_event(unsigned long data)
 298 {
 299         struct sctp_association *asoc = (struct sctp_association *) data;
 300         sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO);
 301 }
 302
 303 void sctp_generate_t5_shutdown_guard_event(unsigned long data)
 304 {
 305         struct sctp_association *asoc = (struct sctp_association *)data;
 306         sctp_generate_timeout_event(asoc,
 307                                     SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD);
 308
 309 } /* sctp_generate_t5_shutdown_guard_event() */
 310
 311 void sctp_generate_autoclose_event(unsigned long data)
 312 {
 313         struct sctp_association *asoc = (struct sctp_association *) data;
 314         sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE);
 315 }
 316
 317 /* Generate a heart beat event.  If the sock is busy, reschedule.   Make
 318  * sure that the transport is still valid.
 319  */
 320 void sctp_generate_heartbeat_event(unsigned long data)
 321 {
 322         int error = 0;
 323         struct sctp_transport *transport = (struct sctp_transport *) data;
 324         struct sctp_association *asoc = transport->asoc;
 325
 326         sctp_bh_lock_sock(asoc->base.sk);
 327         if (sock_owned_by_user(asoc->base.sk)) {
 328                 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __FUNCTION__);
 329
 330                 /* Try again later.  */
 331                 if (!mod_timer(&transport->hb_timer, jiffies + (HZ/20)))
 332                         sctp_transport_hold(transport);
 333                 goto out_unlock;
 334         }
 335
 336         /* Is this structure just waiting around for us to actually
 337          * get destroyed?
 338          */
 339         if (transport->dead)
 340                 goto out_unlock;
 341
 342         error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
 343                            SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT),
 344                            asoc->state, asoc->ep, asoc,
 345                            transport, GFP_ATOMIC);
 346
 347          if (error)
 348                  asoc->base.sk->sk_err = -error;
 349
 350 out_unlock:
 351         sctp_bh_unlock_sock(asoc->base.sk);
 352         sctp_transport_put(transport);
 353 }
 354
 355 /* Inject a SACK Timeout event into the state machine.  */
 356 void sctp_generate_sack_event(unsigned long data)
 357 {
 358         struct sctp_association *asoc = (struct sctp_association *) data;
 359         sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK);
 360 }
 361
 362 sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = {
 363         NULL,
 364         sctp_generate_t1_cookie_event,
 365         sctp_generate_t1_init_event,
 366         sctp_generate_t2_shutdown_event,
 367         NULL,
 368         sctp_generate_t4_rto_event,
 369         sctp_generate_t5_shutdown_guard_event,
 370         sctp_generate_heartbeat_event,
 371         sctp_generate_sack_event,
 372         sctp_generate_autoclose_event,
 373 };
 374
 375
 376 /* RFC 2960 8.2 Path Failure Detection
 377  *
 378  * When its peer endpoint is multi-homed, an endpoint should keep a
 379  * error counter for each of the destination transport addresses of the
 380  * peer endpoint.
 381  *
 382  * Each time the T3-rtx timer expires on any address, or when a
 383  * HEARTBEAT sent to an idle address is not acknowledged within a RTO,
 384  * the error counter of that destination address will be incremented.
 385  * When the value in the error counter exceeds the protocol parameter
 386  * 'Path.Max.Retrans' of that destination address, the endpoint should
 387  * mark the destination transport address as inactive, and a
 388  * notification SHOULD be sent to the upper layer.
 389  *
 390  */
 391 static void sctp_do_8_2_transport_strike(struct sctp_association *asoc,
 392                                          struct sctp_transport *transport)
 393 {
 394         /* The check for association's overall error counter exceeding the
 395          * threshold is done in the state function.
 396          */
 397         asoc->overall_error_count++;
 398
 399         if (transport->active &&
 400             (transport->error_count++ >= transport->error_threshold)) {
 401                 SCTP_DEBUG_PRINTK("transport_strike: transport "
 402                                   "IP:%d.%d.%d.%d failed.\n",
 403                                   NIPQUAD(transport->ipaddr.v4.sin_addr));
 404                 sctp_assoc_control_transport(asoc, transport,
 405                                              SCTP_TRANSPORT_DOWN,
 406                                              SCTP_FAILED_THRESHOLD);
 407         }
 408
 409         /* E2) For the destination address for which the timer
 410          * expires, set RTO <- RTO * 2 ("back off the timer").  The
 411          * maximum value discussed in rule C7 above (RTO.max) may be
 412          * used to provide an upper bound to this doubling operation.
 413          */
 414         transport->rto = min((transport->rto * 2), transport->asoc->rto_max);
 415 }
 416
 417 /* Worker routine to handle INIT command failure.  */
 418 static void sctp_cmd_init_failed(sctp_cmd_seq_t *commands,
 419                                  struct sctp_association *asoc,
 420                                  unsigned error)
 421 {
 422         struct sctp_ulpevent *event;
 423
 424         event = sctp_ulpevent_make_assoc_change(asoc,0, SCTP_CANT_STR_ASSOC,
 425                                                 (__u16)error, 0, 0,
 426                                                 GFP_ATOMIC);
 427
 428         if (event)
 429                 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
 430                                 SCTP_ULPEVENT(event));
 431
 432         sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
 433                         SCTP_STATE(SCTP_STATE_CLOSED));
 434
 435         /* SEND_FAILED sent later when cleaning up the association. */
 436         asoc->outqueue.error = error;
 437         sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
 438 }
 439
 440 /* Worker routine to handle SCTP_CMD_ASSOC_FAILED.  */
 441 static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands,
 442                                   struct sctp_association *asoc,
 443                                   sctp_event_t event_type,
 444                                   sctp_subtype_t subtype,
 445                                   struct sctp_chunk *chunk,
 446                                   unsigned error)
 447 {
 448         struct sctp_ulpevent *event;
 449
 450         /* Cancel any partial delivery in progress. */
 451         sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
 452
 453         event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
 454                                                 (__u16)error, 0, 0,
 455                                                 GFP_ATOMIC);
 456         if (event)
 457                 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
 458                                 SCTP_ULPEVENT(event));
 459
 460         sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
 461                         SCTP_STATE(SCTP_STATE_CLOSED));
 462
 463         /* Set sk_err to ECONNRESET on a 1-1 style socket. */
 464         if (!sctp_style(asoc->base.sk, UDP))
 465                 asoc->base.sk->sk_err = ECONNRESET;
 466
 467         /* SEND_FAILED sent later when cleaning up the association. */
 468         asoc->outqueue.error = error;
 469         sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
 470 }
 471
 472 /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT
 473  * inside the cookie.  In reality, this is only used for INIT-ACK processing
 474  * since all other cases use "temporary" associations and can do all
 475  * their work in statefuns directly.
 476  */
 477 static int sctp_cmd_process_init(sctp_cmd_seq_t *commands,
 478                                  struct sctp_association *asoc,
 479                                  struct sctp_chunk *chunk,
 480                                  sctp_init_chunk_t *peer_init, int gfp)
 481 {
 482         int error;
 483
 484         /* We only process the init as a sideeffect in a single
 485          * case.   This is when we process the INIT-ACK.   If we
 486          * fail during INIT processing (due to malloc problems),
 487          * just return the error and stop processing the stack.
 488          */
 489         if (!sctp_process_init(asoc, chunk->chunk_hdr->type,
 490                                sctp_source(chunk), peer_init, gfp))
 491                 error = -ENOMEM;
 492         else
 493                 error = 0;
 494
 495         return error;
 496 }
 497
 498 /* Helper function to break out starting up of heartbeat timers.  */
 499 static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds,
 500                                      struct sctp_association *asoc)
 501 {
 502         struct sctp_transport *t;
 503         struct list_head *pos;
 504
 505         /* Start a heartbeat timer for each transport on the association.
 506          * hold a reference on the transport to make sure none of
 507          * the needed data structures go away.
 508          */
 509         list_for_each(pos, &asoc->peer.transport_addr_list) {
 510                 t = list_entry(pos, struct sctp_transport, transports);
 511
 512                 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
 513                         sctp_transport_hold(t);
 514         }
 515 }
 516
 517 static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds,
 518                                     struct sctp_association *asoc)
 519 {
 520         struct sctp_transport *t;
 521         struct list_head *pos;
 522
 523         /* Stop all heartbeat timers. */
 524
 525         list_for_each(pos, &asoc->peer.transport_addr_list) {
 526                 t = list_entry(pos, struct sctp_transport, transports);
 527                 if (del_timer(&t->hb_timer))
 528                         sctp_transport_put(t);
 529         }
 530 }
 531
 532 /* Helper function to update the heartbeat timer. */
 533 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds,
 534                                      struct sctp_association *asoc,
 535                                      struct sctp_transport *t)
 536 {
 537         /* Update the heartbeat timer.  */
 538         if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
 539                 sctp_transport_hold(t);
 540 }
 541
 542 /* Helper function to handle the reception of an HEARTBEAT ACK.  */
 543 static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds,
 544                                   struct sctp_association *asoc,
 545                                   struct sctp_transport *t,
 546                                   struct sctp_chunk *chunk)
 547 {
 548         sctp_sender_hb_info_t *hbinfo;
 549
 550         /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the
 551          * HEARTBEAT should clear the error counter of the destination
 552          * transport address to which the HEARTBEAT was sent.
 553          * The association's overall error count is also cleared.
 554          */
 555         t->error_count = 0;
 556         t->asoc->overall_error_count = 0;
 557
 558         /* Mark the destination transport address as active if it is not so
 559          * marked.
 560          */
 561         if (!t->active)
 562                 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
 563                                              SCTP_HEARTBEAT_SUCCESS);
 564
 565         /* The receiver of the HEARTBEAT ACK should also perform an
 566          * RTT measurement for that destination transport address
 567          * using the time value carried in the HEARTBEAT ACK chunk.
 568          */
 569         hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data;
 570         sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at));
 571 }
 572
 573 /* Helper function to do a transport reset at the expiry of the hearbeat
 574  * timer.
 575  */
 576 static void sctp_cmd_transport_reset(sctp_cmd_seq_t *cmds,
 577                                      struct sctp_association *asoc,
 578                                      struct sctp_transport *t)
 579 {
 580         sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE);
 581
 582         /* Mark one strike against a transport.  */
 583         sctp_do_8_2_transport_strike(asoc, t);
 584 }
 585
 586 /* Helper function to process the process SACK command.  */
 587 static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds,
 588                                  struct sctp_association *asoc,
 589                                  struct sctp_sackhdr *sackh)
 590 {
 591         int err;
 592
 593         if (sctp_outq_sack(&asoc->outqueue, sackh)) {
 594                 /* There are no more TSNs awaiting SACK.  */
 595                 err = sctp_do_sm(SCTP_EVENT_T_OTHER,
 596                                  SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN),
 597                                  asoc->state, asoc->ep, asoc, NULL,
 598                                  GFP_ATOMIC);
 599         } else {
 600                 /* Windows may have opened, so we need
 601                  * to check if we have DATA to transmit
 602                  */
 603                 err = sctp_outq_flush(&asoc->outqueue, 0);
 604         }
 605
 606         return err;
 607 }
 608
 609 /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set
 610  * the transport for a shutdown chunk.
 611  */
 612 static void sctp_cmd_setup_t2(sctp_cmd_seq_t *cmds,
 613                               struct sctp_association *asoc,
 614                               struct sctp_chunk *chunk)
 615 {
 616         struct sctp_transport *t;
 617
 618         t = sctp_assoc_choose_shutdown_transport(asoc);
 619         asoc->shutdown_last_sent_to = t;
 620         asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto;
 621         chunk->transport = t;
 622 }
 623
 624 /* Helper function to change the state of an association. */
 625 static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds,
 626                                struct sctp_association *asoc,
 627                                sctp_state_t state)
 628 {
 629         struct sock *sk = asoc->base.sk;
 630
 631         asoc->state = state;
 632
 633         if (sctp_style(sk, TCP)) {
 634                 /* Change the sk->sk_state of a TCP-style socket that has
 635                  * sucessfully completed a connect() call.
 636                  */
 637                 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED))
 638                         sk->sk_state = SCTP_SS_ESTABLISHED;
 639
 640                 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */
 641                 if (sctp_state(asoc, SHUTDOWN_RECEIVED) &&
 642                     sctp_sstate(sk, ESTABLISHED))
 643                         sk->sk_shutdown |= RCV_SHUTDOWN;
 644         }
 645
 646         if (sctp_state(asoc, ESTABLISHED) ||
 647             sctp_state(asoc, CLOSED) ||
 648             sctp_state(asoc, SHUTDOWN_RECEIVED)) {
 649                 /* Wake up any processes waiting in the asoc's wait queue in
 650                  * sctp_wait_for_connect() or sctp_wait_for_sndbuf().
 651                  */
 652                 if (waitqueue_active(&asoc->wait))
 653                         wake_up_interruptible(&asoc->wait);
 654
 655                 /* Wake up any processes waiting in the sk's sleep queue of
 656                  * a TCP-style or UDP-style peeled-off socket in
 657                  * sctp_wait_for_accept() or sctp_wait_for_packet().
 658                  * For a UDP-style socket, the waiters are woken up by the
 659                  * notifications.
 660                  */
 661                 if (!sctp_style(sk, UDP))
 662                         sk->sk_state_change(sk);
 663         }
 664 }
 665
 666 /* Helper function to delete an association. */
 667 static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds,
 668                                 struct sctp_association *asoc)
 669 {
 670         struct sock *sk = asoc->base.sk;
 671
 672         /* If it is a non-temporary association belonging to a TCP-style
 673          * listening socket that is not closed, do not free it so that accept()
 674          * can pick it up later.
 675          */
 676         if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) &&
 677             (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK))
 678                 return;
 679
 680         sctp_unhash_established(asoc);
 681         sctp_association_free(asoc);
 682 }
 683
 684 /*
 685  * ADDIP Section 4.1 ASCONF Chunk Procedures
 686  * A4) Start a T-4 RTO timer, using the RTO value of the selected
 687  * destination address (we use active path instead of primary path just
 688  * because primary path may be inactive.
 689  */
 690 static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds,
 691                                 struct sctp_association *asoc,
 692                                 struct sctp_chunk *chunk)
 693 {
 694         struct sctp_transport *t;
 695
 696         t = asoc->peer.active_path;
 697         asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto;
 698         chunk->transport = t;
 699 }
 700
 701 /* Process an incoming Operation Error Chunk. */
 702 static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds,
 703                                    struct sctp_association *asoc,
 704                                    struct sctp_chunk *chunk)
 705 {
 706         struct sctp_operr_chunk *operr_chunk;
 707         struct sctp_errhdr *err_hdr;
 708
 709         operr_chunk = (struct sctp_operr_chunk *)chunk->chunk_hdr;
 710         err_hdr = &operr_chunk->err_hdr;
 711
 712         switch (err_hdr->cause) {
 713         case SCTP_ERROR_UNKNOWN_CHUNK:
 714         {
 715                 struct sctp_chunkhdr *unk_chunk_hdr;
 716
 717                 unk_chunk_hdr = (struct sctp_chunkhdr *)err_hdr->variable;
 718                 switch (unk_chunk_hdr->type) {
 719                 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with an
 720                  * ERROR chunk reporting that it did not recognized the ASCONF
 721                  * chunk type, the sender of the ASCONF MUST NOT send any
 722                  * further ASCONF chunks and MUST stop its T-4 timer.
 723                  */
 724                 case SCTP_CID_ASCONF:
 725                         asoc->peer.asconf_capable = 0;
 726                         sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP,
 727                                         SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
 728                         break;
 729                 default:
 730                         break;
 731                 }
 732                 break;
 733         }
 734         default:
 735                 break;
 736         }
 737 }
 738
 739 /* Process variable FWDTSN chunk information. */
 740 static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq,
 741                                     struct sctp_chunk *chunk)
 742 {
 743         struct sctp_fwdtsn_skip *skip;
 744         /* Walk through all the skipped SSNs */
 745         sctp_walk_fwdtsn(skip, chunk) {
 746                 sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn));
 747         }
 748
 749         return;
 750 }
 751
 752 /* These three macros allow us to pull the debugging code out of the
 753  * main flow of sctp_do_sm() to keep attention focused on the real
 754  * functionality there.
 755  */
 756 #define DEBUG_PRE \
 757         SCTP_DEBUG_PRINTK("sctp_do_sm prefn: " \
 758                           "ep %p, %s, %s, asoc %p[%s], %s\n", \
 759                           ep, sctp_evttype_tbl[event_type], \
 760                           (*debug_fn)(subtype), asoc, \
 761                           sctp_state_tbl[state], state_fn->name)
 762
 763 #define DEBUG_POST \
 764         SCTP_DEBUG_PRINTK("sctp_do_sm postfn: " \
 765                           "asoc %p, status: %s\n", \
 766                           asoc, sctp_status_tbl[status])
 767
 768 #define DEBUG_POST_SFX \
 769         SCTP_DEBUG_PRINTK("sctp_do_sm post sfx: error %d, asoc %p[%s]\n", \
 770                           error, asoc, \
 771                           sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \
 772                           sctp_assoc2id(asoc)))?asoc->state:SCTP_STATE_CLOSED])
 773
 774 /*
 775  * This is the master state machine processing function.
 776  *
 777  * If you want to understand all of lksctp, this is a
 778  * good place to start.
 779  */
 780 int sctp_do_sm(sctp_event_t event_type, sctp_subtype_t subtype,
 781                sctp_state_t state,
 782                struct sctp_endpoint *ep,
 783                struct sctp_association *asoc,
 784                void *event_arg,
 785                int gfp)
 786 {
 787         sctp_cmd_seq_t commands;
 788         const sctp_sm_table_entry_t *state_fn;
 789         sctp_disposition_t status;
 790         int error = 0;
 791         typedef const char *(printfn_t)(sctp_subtype_t);
 792
 793         static printfn_t *table[] = {
 794                 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname,
 795         };
 796         printfn_t *debug_fn  __attribute__ ((unused)) = table[event_type];
 797
 798         /* Look up the state function, run it, and then process the
 799          * side effects.  These three steps are the heart of lksctp.
 800          */
 801         state_fn = sctp_sm_lookup_event(event_type, state, subtype);
 802
 803         sctp_init_cmd_seq(&commands);
 804
 805         DEBUG_PRE;
 806         status = (*state_fn->fn)(ep, asoc, subtype, event_arg, &commands);
 807         DEBUG_POST;
 808
 809         error = sctp_side_effects(event_type, subtype, state,
 810                                   ep, asoc, event_arg, status,
 811                                   &commands, gfp);
 812         DEBUG_POST_SFX;
 813
 814         return error;
 815 }
 816
 817 #undef DEBUG_PRE
 818 #undef DEBUG_POST
 819
 820 /*****************************************************************
 821  * This the master state function side effect processing function.
 822  *****************************************************************/
 823 int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
 824                       sctp_state_t state,
 825                       struct sctp_endpoint *ep,
 826                       struct sctp_association *asoc,
 827                       void *event_arg,
 828                       sctp_disposition_t status,
 829                       sctp_cmd_seq_t *commands,
 830                       int gfp)
 831 {
 832         int error;
 833
 834         /* FIXME - Most of the dispositions left today would be categorized
 835          * as "exceptional" dispositions.  For those dispositions, it
 836          * may not be proper to run through any of the commands at all.
 837          * For example, the command interpreter might be run only with
 838          * disposition SCTP_DISPOSITION_CONSUME.
 839          */
 840         if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state,
 841                                                ep, asoc,
 842                                                event_arg, status,
 843                                                commands, gfp)))
 844                 goto bail;
 845
 846         switch (status) {
 847         case SCTP_DISPOSITION_DISCARD:
 848                 SCTP_DEBUG_PRINTK("Ignored sctp protocol event - state %d, "
 849                                   "event_type %d, event_id %d\n",
 850                                   state, event_type, subtype.chunk);
 851                 break;
 852
 853         case SCTP_DISPOSITION_NOMEM:
 854                 /* We ran out of memory, so we need to discard this
 855                  * packet.
 856                  */
 857                 /* BUG--we should now recover some memory, probably by
 858                  * reneging...
 859                  */
 860                 error = -ENOMEM;
 861                 break;
 862
 863         case SCTP_DISPOSITION_DELETE_TCB:
 864                 /* This should now be a command. */
 865                 break;
 866
 867         case SCTP_DISPOSITION_CONSUME:
 868         case SCTP_DISPOSITION_ABORT:
 869                 /*
 870                  * We should no longer have much work to do here as the
 871                  * real work has been done as explicit commands above.
 872                  */
 873                 break;
 874
 875         case SCTP_DISPOSITION_VIOLATION:
 876                 printk(KERN_ERR "sctp protocol violation state %d "
 877                        "chunkid %d\n", state, subtype.chunk);
 878                 break;
 879
 880         case SCTP_DISPOSITION_NOT_IMPL:
 881                 printk(KERN_WARNING "sctp unimplemented feature in state %d, "
 882                        "event_type %d, event_id %d\n",
 883                        state, event_type, subtype.chunk);
 884                 break;
 885
 886         case SCTP_DISPOSITION_BUG:
 887                 printk(KERN_ERR "sctp bug in state %d, "
 888                        "event_type %d, event_id %d\n",
 889                        state, event_type, subtype.chunk);
 890                 BUG();
 891                 break;
 892
 893         default:
 894                 printk(KERN_ERR "sctp impossible disposition %d "
 895                        "in state %d, event_type %d, event_id %d\n",
 896                        status, state, event_type, subtype.chunk);
 897                 BUG();
 898                 break;
 899         };
 900
 901 bail:
 902         return error;
 903 }
 904
 905 /********************************************************************
 906  * 2nd Level Abstractions
 907  ********************************************************************/
 908
 909 /* This is the side-effect interpreter.  */
 910 int sctp_cmd_interpreter(sctp_event_t event_type, sctp_subtype_t subtype,
 911                          sctp_state_t state, struct sctp_endpoint *ep,
 912                          struct sctp_association *asoc, void *event_arg,
 913                          sctp_disposition_t status, sctp_cmd_seq_t *commands,
 914                          int gfp)
 915 {
 916         int error = 0;
 917         int force;
 918         sctp_cmd_t *cmd;
 919         struct sctp_chunk *new_obj;
 920         struct sctp_chunk *chunk = NULL;
 921         struct sctp_packet *packet;
 922         struct list_head *pos;
 923         struct timer_list *timer;
 924         unsigned long timeout;
 925         struct sctp_transport *t;
 926         struct sctp_sackhdr sackh;
 927         int local_cork = 0;
 928
 929         if (SCTP_EVENT_T_TIMEOUT != event_type)
 930                 chunk = (struct sctp_chunk *) event_arg;
 931
 932         /* Note:  This whole file is a huge candidate for rework.
 933          * For example, each command could either have its own handler, so
 934          * the loop would look like:
 935          *     while (cmds)
 936          *         cmd->handle(x, y, z)
 937          * --jgrimm
 938          */
 939         while (NULL != (cmd = sctp_next_cmd(commands))) {
 940                 switch (cmd->verb) {
 941                 case SCTP_CMD_NOP:
 942                         /* Do nothing. */
 943                         break;
 944
 945                 case SCTP_CMD_NEW_ASOC:
 946                         /* Register a new association.  */
 947                         if (local_cork) {
 948                                 sctp_outq_uncork(&asoc->outqueue);
 949                                 local_cork = 0;
 950                         }
 951                         asoc = cmd->obj.ptr;
 952                         /* Register with the endpoint.  */
 953                         sctp_endpoint_add_asoc(ep, asoc);
 954                         sctp_hash_established(asoc);
 955                         break;
 956
 957                 case SCTP_CMD_UPDATE_ASSOC:
 958                        sctp_assoc_update(asoc, cmd->obj.ptr);
 959                        break;
 960
 961                 case SCTP_CMD_PURGE_OUTQUEUE:
 962                        sctp_outq_teardown(&asoc->outqueue);
 963                        break;
 964
 965                 case SCTP_CMD_DELETE_TCB:
 966                         if (local_cork) {
 967                                 sctp_outq_uncork(&asoc->outqueue);
 968                                 local_cork = 0;
 969                         }
 970                         /* Delete the current association.  */
 971                         sctp_cmd_delete_tcb(commands, asoc);
 972                         asoc = NULL;
 973                         break;
 974
 975                 case SCTP_CMD_NEW_STATE:
 976                         /* Enter a new state.  */
 977                         sctp_cmd_new_state(commands, asoc, cmd->obj.state);
 978                         break;
 979
 980                 case SCTP_CMD_REPORT_TSN:
 981                         /* Record the arrival of a TSN.  */
 982                         sctp_tsnmap_mark(&asoc->peer.tsn_map, cmd->obj.u32);
 983                         break;
 984
 985                 case SCTP_CMD_REPORT_FWDTSN:
 986                         /* Move the Cumulattive TSN Ack ahead. */
 987                         sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32);
 988
 989                         /* Abort any in progress partial delivery. */
 990                         sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
 991                         break;
 992
 993                 case SCTP_CMD_PROCESS_FWDTSN:
 994                         sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.ptr);
 995                         break;
 996
 997                 case SCTP_CMD_GEN_SACK:
 998                         /* Generate a Selective ACK.
 999                          * The argument tells us whether to just count
1000                          * the packet and MAYBE generate a SACK, or
1001                          * force a SACK out.
1002                          */
1003                         force = cmd->obj.i32;
1004                         error = sctp_gen_sack(asoc, force, commands);
1005                         break;
1006
1007                 case SCTP_CMD_PROCESS_SACK:
1008                         /* Process an inbound SACK.  */
1009                         error = sctp_cmd_process_sack(commands, asoc,
1010                                                       cmd->obj.ptr);
1011                         break;
1012
1013                 case SCTP_CMD_GEN_INIT_ACK:
1014                         /* Generate an INIT ACK chunk.  */
1015                         new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC,
1016                                                      0);
1017                         if (!new_obj)
1018                                 goto nomem;
1019
1020                         sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1021                                         SCTP_CHUNK(new_obj));
1022                         break;
1023
1024                 case SCTP_CMD_PEER_INIT:
1025                         /* Process a unified INIT from the peer.
1026                          * Note: Only used during INIT-ACK processing.  If
1027                          * there is an error just return to the outter
1028                          * layer which will bail.
1029                          */
1030                         error = sctp_cmd_process_init(commands, asoc, chunk,
1031                                                       cmd->obj.ptr, gfp);
1032                         break;
1033
1034                 case SCTP_CMD_GEN_COOKIE_ECHO:
1035                         /* Generate a COOKIE ECHO chunk.  */
1036                         new_obj = sctp_make_cookie_echo(asoc, chunk);
1037                         if (!new_obj) {
1038                                 if (cmd->obj.ptr)
1039                                         sctp_chunk_free(cmd->obj.ptr);
1040                                 goto nomem;
1041                         }
1042                         sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1043                                         SCTP_CHUNK(new_obj));
1044
1045                         /* If there is an ERROR chunk to be sent along with
1046                          * the COOKIE_ECHO, send it, too.
1047                          */
1048                         if (cmd->obj.ptr)
1049                                 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1050                                                 SCTP_CHUNK(cmd->obj.ptr));
1051                         break;
1052
1053                 case SCTP_CMD_GEN_SHUTDOWN:
1054                         /* Generate SHUTDOWN when in SHUTDOWN_SENT state.
1055                          * Reset error counts.
1056                          */
1057                         asoc->overall_error_count = 0;
1058
1059                         /* Generate a SHUTDOWN chunk.  */
1060                         new_obj = sctp_make_shutdown(asoc, chunk);
1061                         if (!new_obj)
1062                                 goto nomem;
1063                         sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1064                                         SCTP_CHUNK(new_obj));
1065                         break;
1066
1067                 case SCTP_CMD_CHUNK_ULP:
1068                         /* Send a chunk to the sockets layer.  */
1069                         SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1070                                           "chunk_up:", cmd->obj.ptr,
1071                                           "ulpq:", &asoc->ulpq);
1072                         sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.ptr,
1073                                             GFP_ATOMIC);
1074                         break;
1075
1076                 case SCTP_CMD_EVENT_ULP:
1077                         /* Send a notification to the sockets layer.  */
1078                         SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1079                                           "event_up:",cmd->obj.ptr,
1080                                           "ulpq:",&asoc->ulpq);
1081                         sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ptr);
1082                         break;
1083
1084                 case SCTP_CMD_REPLY:
1085                         /* If an caller has not already corked, do cork. */
1086                         if (!asoc->outqueue.cork) {
1087                                 sctp_outq_cork(&asoc->outqueue);
1088                                 local_cork = 1;
1089                         }
1090                         /* Send a chunk to our peer.  */
1091                         error = sctp_outq_tail(&asoc->outqueue, cmd->obj.ptr);
1092                         break;
1093
1094                 case SCTP_CMD_SEND_PKT:
1095                         /* Send a full packet to our peer.  */
1096                         packet = cmd->obj.ptr;
1097                         sctp_packet_transmit(packet);
1098                         sctp_ootb_pkt_free(packet);
1099                         break;
1100
1101                 case SCTP_CMD_RETRAN:
1102                         /* Mark a transport for retransmission.  */
1103                         sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1104                                         SCTP_RTXR_T3_RTX);
1105                         break;
1106
1107                 case SCTP_CMD_TRANSMIT:
1108                         /* Kick start transmission. */
1109                         error = sctp_outq_uncork(&asoc->outqueue);
1110                         local_cork = 0;
1111                         break;
1112
1113                 case SCTP_CMD_ECN_CE:
1114                         /* Do delayed CE processing.   */
1115                         sctp_do_ecn_ce_work(asoc, cmd->obj.u32);
1116                         break;
1117
1118                 case SCTP_CMD_ECN_ECNE:
1119                         /* Do delayed ECNE processing. */
1120                         new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32,
1121                                                         chunk);
1122                         if (new_obj)
1123                                 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1124                                                 SCTP_CHUNK(new_obj));
1125                         break;
1126
1127                 case SCTP_CMD_ECN_CWR:
1128                         /* Do delayed CWR processing.  */
1129                         sctp_do_ecn_cwr_work(asoc, cmd->obj.u32);
1130                         break;
1131
1132                 case SCTP_CMD_SETUP_T2:
1133                         sctp_cmd_setup_t2(commands, asoc, cmd->obj.ptr);
1134                         break;
1135
1136                 case SCTP_CMD_TIMER_START:
1137                         timer = &asoc->timers[cmd->obj.to];
1138                         timeout = asoc->timeouts[cmd->obj.to];
1139                         if (!timeout)
1140                                 BUG();
1141
1142                         timer->expires = jiffies + timeout;
1143                         sctp_association_hold(asoc);
1144                         add_timer(timer);
1145                         break;
1146
1147                 case SCTP_CMD_TIMER_RESTART:
1148                         timer = &asoc->timers[cmd->obj.to];
1149                         timeout = asoc->timeouts[cmd->obj.to];
1150                         if (!mod_timer(timer, jiffies + timeout))
1151                                 sctp_association_hold(asoc);
1152                         break;
1153
1154                 case SCTP_CMD_TIMER_STOP:
1155                         timer = &asoc->timers[cmd->obj.to];
1156                         if (timer_pending(timer) && del_timer(timer))
1157                                 sctp_association_put(asoc);
1158                         break;
1159
1160                 case SCTP_CMD_INIT_RESTART:
1161                         /* Do the needed accounting and updates
1162                          * associated with restarting an initialization
1163                          * timer.
1164                          */
1165                         asoc->counters[SCTP_COUNTER_INIT_ERROR]++;
1166                         asoc->timeouts[cmd->obj.to] *= 2;
1167                         if (asoc->timeouts[cmd->obj.to] >
1168                             asoc->max_init_timeo) {
1169                                 asoc->timeouts[cmd->obj.to] =
1170                                         asoc->max_init_timeo;
1171                         }
1172
1173                         /* If we've sent any data bundled with
1174                          * COOKIE-ECHO we need to resend.
1175                          */
1176                         list_for_each(pos, &asoc->peer.transport_addr_list) {
1177                                 t = list_entry(pos, struct sctp_transport,
1178                                                transports);
1179                                 sctp_retransmit_mark(&asoc->outqueue, t, 0);
1180                         }
1181
1182                         sctp_add_cmd_sf(commands,
1183                                         SCTP_CMD_TIMER_RESTART,
1184                                         SCTP_TO(cmd->obj.to));
1185                         break;
1186
1187                 case SCTP_CMD_INIT_FAILED:
1188                         sctp_cmd_init_failed(commands, asoc, cmd->obj.u32);
1189                         break;
1190
1191                 case SCTP_CMD_ASSOC_FAILED:
1192                         sctp_cmd_assoc_failed(commands, asoc, event_type,
1193                                               subtype, chunk, cmd->obj.u32);
1194                         break;
1195
1196                 case SCTP_CMD_COUNTER_INC:
1197                         asoc->counters[cmd->obj.counter]++;
1198                         break;
1199
1200                 case SCTP_CMD_COUNTER_RESET:
1201                         asoc->counters[cmd->obj.counter] = 0;
1202                         break;
1203
1204                 case SCTP_CMD_REPORT_DUP:
1205                         sctp_tsnmap_mark_dup(&asoc->peer.tsn_map,
1206                                              cmd->obj.u32);
1207                         break;
1208
1209                 case SCTP_CMD_REPORT_BAD_TAG:
1210                         SCTP_DEBUG_PRINTK("vtag mismatch!\n");
1211                         break;
1212
1213                 case SCTP_CMD_STRIKE:
1214                         /* Mark one strike against a transport.  */
1215                         sctp_do_8_2_transport_strike(asoc, cmd->obj.transport);
1216                         break;
1217
1218                 case SCTP_CMD_TRANSPORT_RESET:
1219                         t = cmd->obj.transport;
1220                         sctp_cmd_transport_reset(commands, asoc, t);
1221                         break;
1222
1223                 case SCTP_CMD_TRANSPORT_ON:
1224                         t = cmd->obj.transport;
1225                         sctp_cmd_transport_on(commands, asoc, t, chunk);
1226                         break;
1227
1228                 case SCTP_CMD_HB_TIMERS_START:
1229                         sctp_cmd_hb_timers_start(commands, asoc);
1230                         break;
1231
1232                 case SCTP_CMD_HB_TIMER_UPDATE:
1233                         t = cmd->obj.transport;
1234                         sctp_cmd_hb_timer_update(commands, asoc, t);
1235                         break;
1236
1237                 case SCTP_CMD_HB_TIMERS_STOP:
1238                         sctp_cmd_hb_timers_stop(commands, asoc);
1239                         break;
1240
1241                 case SCTP_CMD_REPORT_ERROR:
1242                         error = cmd->obj.error;
1243                         break;
1244
1245                 case SCTP_CMD_PROCESS_CTSN:
1246                         /* Dummy up a SACK for processing. */
1247                         sackh.cum_tsn_ack = cmd->obj.u32;
1248                         sackh.a_rwnd = 0;
1249                         sackh.num_gap_ack_blocks = 0;
1250                         sackh.num_dup_tsns = 0;
1251                         sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK,
1252                                         SCTP_SACKH(&sackh));
1253                         break;
1254
1255                 case SCTP_CMD_DISCARD_PACKET:
1256                         /* We need to discard the whole packet.  */
1257                         chunk->pdiscard = 1;
1258                         break;
1259
1260                 case SCTP_CMD_RTO_PENDING:
1261                         t = cmd->obj.transport;
1262                         t->rto_pending = 1;
1263                         break;
1264
1265                 case SCTP_CMD_PART_DELIVER:
1266                         sctp_ulpq_partial_delivery(&asoc->ulpq, cmd->obj.ptr,
1267                                                    GFP_ATOMIC);
1268                         break;
1269
1270                 case SCTP_CMD_RENEGE:
1271                         sctp_ulpq_renege(&asoc->ulpq, cmd->obj.ptr,
1272                                          GFP_ATOMIC);
1273                         break;
1274
1275                 case SCTP_CMD_SETUP_T4:
1276                         sctp_cmd_setup_t4(commands, asoc, cmd->obj.ptr);
1277                         break;
1278
1279                 case SCTP_CMD_PROCESS_OPERR:
1280                         sctp_cmd_process_operr(commands, asoc, chunk);
1281                         break;
1282                 case SCTP_CMD_CLEAR_INIT_TAG:
1283                         asoc->peer.i.init_tag = 0;
1284                         break;
1285                 default:
1286                         printk(KERN_WARNING "Impossible command: %u, %p\n",
1287                                cmd->verb, cmd->obj.ptr);
1288                         break;
1289                 };
1290                 if (error)
1291                         break;
1292         }
1293
1294 out:
1295         if (local_cork)
1296                 sctp_outq_uncork(&asoc->outqueue);
1297         return error;
1298 nomem:
1299         error = -ENOMEM;
1300         goto out;
1301 }
1302