[NET]: cleanup extra semicolons
[linux-2.6.git] / 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 static int sctp_cmd_interpreter(sctp_event_t event_type,
59                                 sctp_subtype_t subtype,
60                                 sctp_state_t state,
61                                 struct sctp_endpoint *ep,
62                                 struct sctp_association *asoc,
63                                 void *event_arg,
64                                 sctp_disposition_t status,
65                                 sctp_cmd_seq_t *commands,
66                                 gfp_t gfp);
67 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
68                              sctp_state_t state,
69                              struct sctp_endpoint *ep,
70                              struct sctp_association *asoc,
71                              void *event_arg,
72                              sctp_disposition_t status,
73                              sctp_cmd_seq_t *commands,
74                              gfp_t gfp);
75
76 /********************************************************************
77  * Helper functions
78  ********************************************************************/
79
80 /* A helper function for delayed processing of INET ECN CE bit. */
81 static void sctp_do_ecn_ce_work(struct sctp_association *asoc,
82                                 __u32 lowest_tsn)
83 {
84         /* Save the TSN away for comparison when we receive CWR */
85
86         asoc->last_ecne_tsn = lowest_tsn;
87         asoc->need_ecne = 1;
88 }
89
90 /* Helper function for delayed processing of SCTP ECNE chunk.  */
91 /* RFC 2960 Appendix A
92  *
93  * RFC 2481 details a specific bit for a sender to send in
94  * the header of its next outbound TCP segment to indicate to
95  * its peer that it has reduced its congestion window.  This
96  * is termed the CWR bit.  For SCTP the same indication is made
97  * by including the CWR chunk.  This chunk contains one data
98  * element, i.e. the TSN number that was sent in the ECNE chunk.
99  * This element represents the lowest TSN number in the datagram
100  * that was originally marked with the CE bit.
101  */
102 static struct sctp_chunk *sctp_do_ecn_ecne_work(struct sctp_association *asoc,
103                                            __u32 lowest_tsn,
104                                            struct sctp_chunk *chunk)
105 {
106         struct sctp_chunk *repl;
107
108         /* Our previously transmitted packet ran into some congestion
109          * so we should take action by reducing cwnd and ssthresh
110          * and then ACK our peer that we we've done so by
111          * sending a CWR.
112          */
113
114         /* First, try to determine if we want to actually lower
115          * our cwnd variables.  Only lower them if the ECNE looks more
116          * recent than the last response.
117          */
118         if (TSN_lt(asoc->last_cwr_tsn, lowest_tsn)) {
119                 struct sctp_transport *transport;
120
121                 /* Find which transport's congestion variables
122                  * need to be adjusted.
123                  */
124                 transport = sctp_assoc_lookup_tsn(asoc, lowest_tsn);
125
126                 /* Update the congestion variables. */
127                 if (transport)
128                         sctp_transport_lower_cwnd(transport,
129                                                   SCTP_LOWER_CWND_ECNE);
130                 asoc->last_cwr_tsn = lowest_tsn;
131         }
132
133         /* Always try to quiet the other end.  In case of lost CWR,
134          * resend last_cwr_tsn.
135          */
136         repl = sctp_make_cwr(asoc, asoc->last_cwr_tsn, chunk);
137
138         /* If we run out of memory, it will look like a lost CWR.  We'll
139          * get back in sync eventually.
140          */
141         return repl;
142 }
143
144 /* Helper function to do delayed processing of ECN CWR chunk.  */
145 static void sctp_do_ecn_cwr_work(struct sctp_association *asoc,
146                                  __u32 lowest_tsn)
147 {
148         /* Turn off ECNE getting auto-prepended to every outgoing
149          * packet
150          */
151         asoc->need_ecne = 0;
152 }
153
154 /* Generate SACK if necessary.  We call this at the end of a packet.  */
155 static int sctp_gen_sack(struct sctp_association *asoc, int force,
156                          sctp_cmd_seq_t *commands)
157 {
158         __u32 ctsn, max_tsn_seen;
159         struct sctp_chunk *sack;
160         struct sctp_transport *trans = asoc->peer.last_data_from;
161         int error = 0;
162
163         if (force ||
164             (!trans && (asoc->param_flags & SPP_SACKDELAY_DISABLE)) ||
165             (trans && (trans->param_flags & SPP_SACKDELAY_DISABLE)))
166                 asoc->peer.sack_needed = 1;
167
168         ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
169         max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
170
171         /* From 12.2 Parameters necessary per association (i.e. the TCB):
172          *
173          * Ack State : This flag indicates if the next received packet
174          *           : is to be responded to with a SACK. ...
175          *           : When DATA chunks are out of order, SACK's
176          *           : are not delayed (see Section 6).
177          *
178          * [This is actually not mentioned in Section 6, but we
179          * implement it here anyway. --piggy]
180          */
181         if (max_tsn_seen != ctsn)
182                 asoc->peer.sack_needed = 1;
183
184         /* From 6.2  Acknowledgement on Reception of DATA Chunks:
185          *
186          * Section 4.2 of [RFC2581] SHOULD be followed. Specifically,
187          * an acknowledgement SHOULD be generated for at least every
188          * second packet (not every second DATA chunk) received, and
189          * SHOULD be generated within 200 ms of the arrival of any
190          * unacknowledged DATA chunk. ...
191          */
192         if (!asoc->peer.sack_needed) {
193                 /* We will need a SACK for the next packet.  */
194                 asoc->peer.sack_needed = 1;
195
196                 /* Set the SACK delay timeout based on the
197                  * SACK delay for the last transport
198                  * data was received from, or the default
199                  * for the association.
200                  */
201                 if (trans)
202                         asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
203                                 trans->sackdelay;
204                 else
205                         asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
206                                 asoc->sackdelay;
207
208                 /* Restart the SACK timer. */
209                 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
210                                 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
211         } else {
212                 if (asoc->a_rwnd > asoc->rwnd)
213                         asoc->a_rwnd = asoc->rwnd;
214                 sack = sctp_make_sack(asoc);
215                 if (!sack)
216                         goto nomem;
217
218                 asoc->peer.sack_needed = 0;
219
220                 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(sack));
221
222                 /* Stop the SACK timer.  */
223                 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
224                                 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
225         }
226
227         return error;
228 nomem:
229         error = -ENOMEM;
230         return error;
231 }
232
233 /* When the T3-RTX timer expires, it calls this function to create the
234  * relevant state machine event.
235  */
236 void sctp_generate_t3_rtx_event(unsigned long peer)
237 {
238         int error;
239         struct sctp_transport *transport = (struct sctp_transport *) peer;
240         struct sctp_association *asoc = transport->asoc;
241
242         /* Check whether a task is in the sock.  */
243
244         sctp_bh_lock_sock(asoc->base.sk);
245         if (sock_owned_by_user(asoc->base.sk)) {
246                 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __FUNCTION__);
247
248                 /* Try again later.  */
249                 if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20)))
250                         sctp_transport_hold(transport);
251                 goto out_unlock;
252         }
253
254         /* Is this transport really dead and just waiting around for
255          * the timer to let go of the reference?
256          */
257         if (transport->dead)
258                 goto out_unlock;
259
260         /* Run through the state machine.  */
261         error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
262                            SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX),
263                            asoc->state,
264                            asoc->ep, asoc,
265                            transport, GFP_ATOMIC);
266
267         if (error)
268                 asoc->base.sk->sk_err = -error;
269
270 out_unlock:
271         sctp_bh_unlock_sock(asoc->base.sk);
272         sctp_transport_put(transport);
273 }
274
275 /* This is a sa interface for producing timeout events.  It works
276  * for timeouts which use the association as their parameter.
277  */
278 static void sctp_generate_timeout_event(struct sctp_association *asoc,
279                                         sctp_event_timeout_t timeout_type)
280 {
281         int error = 0;
282
283         sctp_bh_lock_sock(asoc->base.sk);
284         if (sock_owned_by_user(asoc->base.sk)) {
285                 SCTP_DEBUG_PRINTK("%s:Sock is busy: timer %d\n",
286                                   __FUNCTION__,
287                                   timeout_type);
288
289                 /* Try again later.  */
290                 if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20)))
291                         sctp_association_hold(asoc);
292                 goto out_unlock;
293         }
294
295         /* Is this association really dead and just waiting around for
296          * the timer to let go of the reference?
297          */
298         if (asoc->base.dead)
299                 goto out_unlock;
300
301         /* Run through the state machine.  */
302         error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
303                            SCTP_ST_TIMEOUT(timeout_type),
304                            asoc->state, asoc->ep, asoc,
305                            (void *)timeout_type, GFP_ATOMIC);
306
307         if (error)
308                 asoc->base.sk->sk_err = -error;
309
310 out_unlock:
311         sctp_bh_unlock_sock(asoc->base.sk);
312         sctp_association_put(asoc);
313 }
314
315 static void sctp_generate_t1_cookie_event(unsigned long data)
316 {
317         struct sctp_association *asoc = (struct sctp_association *) data;
318         sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE);
319 }
320
321 static void sctp_generate_t1_init_event(unsigned long data)
322 {
323         struct sctp_association *asoc = (struct sctp_association *) data;
324         sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT);
325 }
326
327 static void sctp_generate_t2_shutdown_event(unsigned long data)
328 {
329         struct sctp_association *asoc = (struct sctp_association *) data;
330         sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN);
331 }
332
333 static void sctp_generate_t4_rto_event(unsigned long data)
334 {
335         struct sctp_association *asoc = (struct sctp_association *) data;
336         sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO);
337 }
338
339 static void sctp_generate_t5_shutdown_guard_event(unsigned long data)
340 {
341         struct sctp_association *asoc = (struct sctp_association *)data;
342         sctp_generate_timeout_event(asoc,
343                                     SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD);
344
345 } /* sctp_generate_t5_shutdown_guard_event() */
346
347 static void sctp_generate_autoclose_event(unsigned long data)
348 {
349         struct sctp_association *asoc = (struct sctp_association *) data;
350         sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE);
351 }
352
353 /* Generate a heart beat event.  If the sock is busy, reschedule.   Make
354  * sure that the transport is still valid.
355  */
356 void sctp_generate_heartbeat_event(unsigned long data)
357 {
358         int error = 0;
359         struct sctp_transport *transport = (struct sctp_transport *) data;
360         struct sctp_association *asoc = transport->asoc;
361
362         sctp_bh_lock_sock(asoc->base.sk);
363         if (sock_owned_by_user(asoc->base.sk)) {
364                 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __FUNCTION__);
365
366                 /* Try again later.  */
367                 if (!mod_timer(&transport->hb_timer, jiffies + (HZ/20)))
368                         sctp_transport_hold(transport);
369                 goto out_unlock;
370         }
371
372         /* Is this structure just waiting around for us to actually
373          * get destroyed?
374          */
375         if (transport->dead)
376                 goto out_unlock;
377
378         error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
379                            SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT),
380                            asoc->state, asoc->ep, asoc,
381                            transport, GFP_ATOMIC);
382
383          if (error)
384                  asoc->base.sk->sk_err = -error;
385
386 out_unlock:
387         sctp_bh_unlock_sock(asoc->base.sk);
388         sctp_transport_put(transport);
389 }
390
391 /* Inject a SACK Timeout event into the state machine.  */
392 static void sctp_generate_sack_event(unsigned long data)
393 {
394         struct sctp_association *asoc = (struct sctp_association *) data;
395         sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK);
396 }
397
398 sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = {
399         NULL,
400         sctp_generate_t1_cookie_event,
401         sctp_generate_t1_init_event,
402         sctp_generate_t2_shutdown_event,
403         NULL,
404         sctp_generate_t4_rto_event,
405         sctp_generate_t5_shutdown_guard_event,
406         NULL,
407         sctp_generate_sack_event,
408         sctp_generate_autoclose_event,
409 };
410
411
412 /* RFC 2960 8.2 Path Failure Detection
413  *
414  * When its peer endpoint is multi-homed, an endpoint should keep a
415  * error counter for each of the destination transport addresses of the
416  * peer endpoint.
417  *
418  * Each time the T3-rtx timer expires on any address, or when a
419  * HEARTBEAT sent to an idle address is not acknowledged within a RTO,
420  * the error counter of that destination address will be incremented.
421  * When the value in the error counter exceeds the protocol parameter
422  * 'Path.Max.Retrans' of that destination address, the endpoint should
423  * mark the destination transport address as inactive, and a
424  * notification SHOULD be sent to the upper layer.
425  *
426  */
427 static void sctp_do_8_2_transport_strike(struct sctp_association *asoc,
428                                          struct sctp_transport *transport)
429 {
430         /* The check for association's overall error counter exceeding the
431          * threshold is done in the state function.
432          */
433         /* When probing UNCONFIRMED addresses, the association overall
434          * error count is NOT incremented
435          */
436         if (transport->state != SCTP_UNCONFIRMED)
437                 asoc->overall_error_count++;
438
439         if (transport->state != SCTP_INACTIVE &&
440             (transport->error_count++ >= transport->pathmaxrxt)) {
441                 SCTP_DEBUG_PRINTK_IPADDR("transport_strike:association %p",
442                                          " transport IP: port:%d failed.\n",
443                                          asoc,
444                                          (&transport->ipaddr),
445                                          ntohs(transport->ipaddr.v4.sin_port));
446                 sctp_assoc_control_transport(asoc, transport,
447                                              SCTP_TRANSPORT_DOWN,
448                                              SCTP_FAILED_THRESHOLD);
449         }
450
451         /* E2) For the destination address for which the timer
452          * expires, set RTO <- RTO * 2 ("back off the timer").  The
453          * maximum value discussed in rule C7 above (RTO.max) may be
454          * used to provide an upper bound to this doubling operation.
455          */
456         transport->rto = min((transport->rto * 2), transport->asoc->rto_max);
457 }
458
459 /* Worker routine to handle INIT command failure.  */
460 static void sctp_cmd_init_failed(sctp_cmd_seq_t *commands,
461                                  struct sctp_association *asoc,
462                                  unsigned error)
463 {
464         struct sctp_ulpevent *event;
465
466         event = sctp_ulpevent_make_assoc_change(asoc,0, SCTP_CANT_STR_ASSOC,
467                                                 (__u16)error, 0, 0, NULL,
468                                                 GFP_ATOMIC);
469
470         if (event)
471                 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
472                                 SCTP_ULPEVENT(event));
473
474         sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
475                         SCTP_STATE(SCTP_STATE_CLOSED));
476
477         /* SEND_FAILED sent later when cleaning up the association. */
478         asoc->outqueue.error = error;
479         sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
480 }
481
482 /* Worker routine to handle SCTP_CMD_ASSOC_FAILED.  */
483 static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands,
484                                   struct sctp_association *asoc,
485                                   sctp_event_t event_type,
486                                   sctp_subtype_t subtype,
487                                   struct sctp_chunk *chunk,
488                                   unsigned error)
489 {
490         struct sctp_ulpevent *event;
491
492         /* Cancel any partial delivery in progress. */
493         sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
494
495         if (event_type == SCTP_EVENT_T_CHUNK && subtype.chunk == SCTP_CID_ABORT)
496                 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
497                                                 (__u16)error, 0, 0, chunk,
498                                                 GFP_ATOMIC);
499         else
500                 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
501                                                 (__u16)error, 0, 0, NULL,
502                                                 GFP_ATOMIC);
503         if (event)
504                 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
505                                 SCTP_ULPEVENT(event));
506
507         sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
508                         SCTP_STATE(SCTP_STATE_CLOSED));
509
510         /* SEND_FAILED sent later when cleaning up the association. */
511         asoc->outqueue.error = error;
512         sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
513 }
514
515 /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT
516  * inside the cookie.  In reality, this is only used for INIT-ACK processing
517  * since all other cases use "temporary" associations and can do all
518  * their work in statefuns directly.
519  */
520 static int sctp_cmd_process_init(sctp_cmd_seq_t *commands,
521                                  struct sctp_association *asoc,
522                                  struct sctp_chunk *chunk,
523                                  sctp_init_chunk_t *peer_init,
524                                  gfp_t gfp)
525 {
526         int error;
527
528         /* We only process the init as a sideeffect in a single
529          * case.   This is when we process the INIT-ACK.   If we
530          * fail during INIT processing (due to malloc problems),
531          * just return the error and stop processing the stack.
532          */
533         if (!sctp_process_init(asoc, chunk->chunk_hdr->type,
534                                sctp_source(chunk), peer_init, gfp))
535                 error = -ENOMEM;
536         else
537                 error = 0;
538
539         return error;
540 }
541
542 /* Helper function to break out starting up of heartbeat timers.  */
543 static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds,
544                                      struct sctp_association *asoc)
545 {
546         struct sctp_transport *t;
547         struct list_head *pos;
548
549         /* Start a heartbeat timer for each transport on the association.
550          * hold a reference on the transport to make sure none of
551          * the needed data structures go away.
552          */
553         list_for_each(pos, &asoc->peer.transport_addr_list) {
554                 t = list_entry(pos, struct sctp_transport, transports);
555
556                 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
557                         sctp_transport_hold(t);
558         }
559 }
560
561 static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds,
562                                     struct sctp_association *asoc)
563 {
564         struct sctp_transport *t;
565         struct list_head *pos;
566
567         /* Stop all heartbeat timers. */
568
569         list_for_each(pos, &asoc->peer.transport_addr_list) {
570                 t = list_entry(pos, struct sctp_transport, transports);
571                 if (del_timer(&t->hb_timer))
572                         sctp_transport_put(t);
573         }
574 }
575
576 /* Helper function to stop any pending T3-RTX timers */
577 static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds,
578                                         struct sctp_association *asoc)
579 {
580         struct sctp_transport *t;
581         struct list_head *pos;
582
583         list_for_each(pos, &asoc->peer.transport_addr_list) {
584                 t = list_entry(pos, struct sctp_transport, transports);
585                 if (timer_pending(&t->T3_rtx_timer) &&
586                     del_timer(&t->T3_rtx_timer)) {
587                         sctp_transport_put(t);
588                 }
589         }
590 }
591
592
593 /* Helper function to update the heartbeat timer. */
594 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds,
595                                      struct sctp_association *asoc,
596                                      struct sctp_transport *t)
597 {
598         /* Update the heartbeat timer.  */
599         if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
600                 sctp_transport_hold(t);
601 }
602
603 /* Helper function to handle the reception of an HEARTBEAT ACK.  */
604 static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds,
605                                   struct sctp_association *asoc,
606                                   struct sctp_transport *t,
607                                   struct sctp_chunk *chunk)
608 {
609         sctp_sender_hb_info_t *hbinfo;
610
611         /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the
612          * HEARTBEAT should clear the error counter of the destination
613          * transport address to which the HEARTBEAT was sent.
614          * The association's overall error count is also cleared.
615          */
616         t->error_count = 0;
617         t->asoc->overall_error_count = 0;
618
619         /* Mark the destination transport address as active if it is not so
620          * marked.
621          */
622         if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED))
623                 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
624                                              SCTP_HEARTBEAT_SUCCESS);
625
626         /* The receiver of the HEARTBEAT ACK should also perform an
627          * RTT measurement for that destination transport address
628          * using the time value carried in the HEARTBEAT ACK chunk.
629          * If the transport's rto_pending variable has been cleared,
630          * it was most likely due to a retransmit.  However, we want
631          * to re-enable it to properly update the rto.
632          */
633         if (t->rto_pending == 0)
634                 t->rto_pending = 1;
635
636         hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data;
637         sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at));
638
639         /* Update the heartbeat timer.  */
640         if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
641                 sctp_transport_hold(t);
642 }
643
644 /* Helper function to do a transport reset at the expiry of the hearbeat
645  * timer.
646  */
647 static void sctp_cmd_transport_reset(sctp_cmd_seq_t *cmds,
648                                      struct sctp_association *asoc,
649                                      struct sctp_transport *t)
650 {
651         sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE);
652
653         /* Mark one strike against a transport.  */
654         sctp_do_8_2_transport_strike(asoc, t);
655 }
656
657 /* Helper function to process the process SACK command.  */
658 static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds,
659                                  struct sctp_association *asoc,
660                                  struct sctp_sackhdr *sackh)
661 {
662         int err;
663
664         if (sctp_outq_sack(&asoc->outqueue, sackh)) {
665                 /* There are no more TSNs awaiting SACK.  */
666                 err = sctp_do_sm(SCTP_EVENT_T_OTHER,
667                                  SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN),
668                                  asoc->state, asoc->ep, asoc, NULL,
669                                  GFP_ATOMIC);
670         } else {
671                 /* Windows may have opened, so we need
672                  * to check if we have DATA to transmit
673                  */
674                 err = sctp_outq_flush(&asoc->outqueue, 0);
675         }
676
677         return err;
678 }
679
680 /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set
681  * the transport for a shutdown chunk.
682  */
683 static void sctp_cmd_setup_t2(sctp_cmd_seq_t *cmds,
684                               struct sctp_association *asoc,
685                               struct sctp_chunk *chunk)
686 {
687         struct sctp_transport *t;
688
689         t = sctp_assoc_choose_shutdown_transport(asoc);
690         asoc->shutdown_last_sent_to = t;
691         asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto;
692         chunk->transport = t;
693 }
694
695 /* Helper function to change the state of an association. */
696 static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds,
697                                struct sctp_association *asoc,
698                                sctp_state_t state)
699 {
700         struct sock *sk = asoc->base.sk;
701
702         asoc->state = state;
703
704         SCTP_DEBUG_PRINTK("sctp_cmd_new_state: asoc %p[%s]\n",
705                           asoc, sctp_state_tbl[state]);
706
707         if (sctp_style(sk, TCP)) {
708                 /* Change the sk->sk_state of a TCP-style socket that has
709                  * sucessfully completed a connect() call.
710                  */
711                 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED))
712                         sk->sk_state = SCTP_SS_ESTABLISHED;
713
714                 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */
715                 if (sctp_state(asoc, SHUTDOWN_RECEIVED) &&
716                     sctp_sstate(sk, ESTABLISHED))
717                         sk->sk_shutdown |= RCV_SHUTDOWN;
718         }
719
720         if (sctp_state(asoc, COOKIE_WAIT)) {
721                 /* Reset init timeouts since they may have been
722                  * increased due to timer expirations.
723                  */
724                 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
725                                                 asoc->rto_initial;
726                 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
727                                                 asoc->rto_initial;
728         }
729
730         if (sctp_state(asoc, ESTABLISHED) ||
731             sctp_state(asoc, CLOSED) ||
732             sctp_state(asoc, SHUTDOWN_RECEIVED)) {
733                 /* Wake up any processes waiting in the asoc's wait queue in
734                  * sctp_wait_for_connect() or sctp_wait_for_sndbuf().
735                  */
736                 if (waitqueue_active(&asoc->wait))
737                         wake_up_interruptible(&asoc->wait);
738
739                 /* Wake up any processes waiting in the sk's sleep queue of
740                  * a TCP-style or UDP-style peeled-off socket in
741                  * sctp_wait_for_accept() or sctp_wait_for_packet().
742                  * For a UDP-style socket, the waiters are woken up by the
743                  * notifications.
744                  */
745                 if (!sctp_style(sk, UDP))
746                         sk->sk_state_change(sk);
747         }
748 }
749
750 /* Helper function to delete an association. */
751 static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds,
752                                 struct sctp_association *asoc)
753 {
754         struct sock *sk = asoc->base.sk;
755
756         /* If it is a non-temporary association belonging to a TCP-style
757          * listening socket that is not closed, do not free it so that accept()
758          * can pick it up later.
759          */
760         if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) &&
761             (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK))
762                 return;
763
764         sctp_unhash_established(asoc);
765         sctp_association_free(asoc);
766 }
767
768 /*
769  * ADDIP Section 4.1 ASCONF Chunk Procedures
770  * A4) Start a T-4 RTO timer, using the RTO value of the selected
771  * destination address (we use active path instead of primary path just
772  * because primary path may be inactive.
773  */
774 static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds,
775                                 struct sctp_association *asoc,
776                                 struct sctp_chunk *chunk)
777 {
778         struct sctp_transport *t;
779
780         t = asoc->peer.active_path;
781         asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto;
782         chunk->transport = t;
783 }
784
785 /* Process an incoming Operation Error Chunk. */
786 static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds,
787                                    struct sctp_association *asoc,
788                                    struct sctp_chunk *chunk)
789 {
790         struct sctp_operr_chunk *operr_chunk;
791         struct sctp_errhdr *err_hdr;
792
793         operr_chunk = (struct sctp_operr_chunk *)chunk->chunk_hdr;
794         err_hdr = &operr_chunk->err_hdr;
795
796         switch (err_hdr->cause) {
797         case SCTP_ERROR_UNKNOWN_CHUNK:
798         {
799                 struct sctp_chunkhdr *unk_chunk_hdr;
800
801                 unk_chunk_hdr = (struct sctp_chunkhdr *)err_hdr->variable;
802                 switch (unk_chunk_hdr->type) {
803                 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with an
804                  * ERROR chunk reporting that it did not recognized the ASCONF
805                  * chunk type, the sender of the ASCONF MUST NOT send any
806                  * further ASCONF chunks and MUST stop its T-4 timer.
807                  */
808                 case SCTP_CID_ASCONF:
809                         asoc->peer.asconf_capable = 0;
810                         sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP,
811                                         SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
812                         break;
813                 default:
814                         break;
815                 }
816                 break;
817         }
818         default:
819                 break;
820         }
821 }
822
823 /* Process variable FWDTSN chunk information. */
824 static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq,
825                                     struct sctp_chunk *chunk)
826 {
827         struct sctp_fwdtsn_skip *skip;
828         /* Walk through all the skipped SSNs */
829         sctp_walk_fwdtsn(skip, chunk) {
830                 sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn));
831         }
832
833         return;
834 }
835
836 /* Helper function to remove the association non-primary peer
837  * transports.
838  */
839 static void sctp_cmd_del_non_primary(struct sctp_association *asoc)
840 {
841         struct sctp_transport *t;
842         struct list_head *pos;
843         struct list_head *temp;
844
845         list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
846                 t = list_entry(pos, struct sctp_transport, transports);
847                 if (!sctp_cmp_addr_exact(&t->ipaddr,
848                                          &asoc->peer.primary_addr)) {
849                         sctp_assoc_del_peer(asoc, &t->ipaddr);
850                 }
851         }
852
853         return;
854 }
855
856 /* Helper function to set sk_err on a 1-1 style socket. */
857 static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error)
858 {
859         struct sock *sk = asoc->base.sk;
860
861         if (!sctp_style(sk, UDP))
862                 sk->sk_err = error;
863 }
864
865 /* These three macros allow us to pull the debugging code out of the
866  * main flow of sctp_do_sm() to keep attention focused on the real
867  * functionality there.
868  */
869 #define DEBUG_PRE \
870         SCTP_DEBUG_PRINTK("sctp_do_sm prefn: " \
871                           "ep %p, %s, %s, asoc %p[%s], %s\n", \
872                           ep, sctp_evttype_tbl[event_type], \
873                           (*debug_fn)(subtype), asoc, \
874                           sctp_state_tbl[state], state_fn->name)
875
876 #define DEBUG_POST \
877         SCTP_DEBUG_PRINTK("sctp_do_sm postfn: " \
878                           "asoc %p, status: %s\n", \
879                           asoc, sctp_status_tbl[status])
880
881 #define DEBUG_POST_SFX \
882         SCTP_DEBUG_PRINTK("sctp_do_sm post sfx: error %d, asoc %p[%s]\n", \
883                           error, asoc, \
884                           sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \
885                           sctp_assoc2id(asoc)))?asoc->state:SCTP_STATE_CLOSED])
886
887 /*
888  * This is the master state machine processing function.
889  *
890  * If you want to understand all of lksctp, this is a
891  * good place to start.
892  */
893 int sctp_do_sm(sctp_event_t event_type, sctp_subtype_t subtype,
894                sctp_state_t state,
895                struct sctp_endpoint *ep,
896                struct sctp_association *asoc,
897                void *event_arg,
898                gfp_t gfp)
899 {
900         sctp_cmd_seq_t commands;
901         const sctp_sm_table_entry_t *state_fn;
902         sctp_disposition_t status;
903         int error = 0;
904         typedef const char *(printfn_t)(sctp_subtype_t);
905
906         static printfn_t *table[] = {
907                 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname,
908         };
909         printfn_t *debug_fn  __attribute__ ((unused)) = table[event_type];
910
911         /* Look up the state function, run it, and then process the
912          * side effects.  These three steps are the heart of lksctp.
913          */
914         state_fn = sctp_sm_lookup_event(event_type, state, subtype);
915
916         sctp_init_cmd_seq(&commands);
917
918         DEBUG_PRE;
919         status = (*state_fn->fn)(ep, asoc, subtype, event_arg, &commands);
920         DEBUG_POST;
921
922         error = sctp_side_effects(event_type, subtype, state,
923                                   ep, asoc, event_arg, status,
924                                   &commands, gfp);
925         DEBUG_POST_SFX;
926
927         return error;
928 }
929
930 #undef DEBUG_PRE
931 #undef DEBUG_POST
932
933 /*****************************************************************
934  * This the master state function side effect processing function.
935  *****************************************************************/
936 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
937                              sctp_state_t state,
938                              struct sctp_endpoint *ep,
939                              struct sctp_association *asoc,
940                              void *event_arg,
941                              sctp_disposition_t status,
942                              sctp_cmd_seq_t *commands,
943                              gfp_t gfp)
944 {
945         int error;
946
947         /* FIXME - Most of the dispositions left today would be categorized
948          * as "exceptional" dispositions.  For those dispositions, it
949          * may not be proper to run through any of the commands at all.
950          * For example, the command interpreter might be run only with
951          * disposition SCTP_DISPOSITION_CONSUME.
952          */
953         if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state,
954                                                ep, asoc,
955                                                event_arg, status,
956                                                commands, gfp)))
957                 goto bail;
958
959         switch (status) {
960         case SCTP_DISPOSITION_DISCARD:
961                 SCTP_DEBUG_PRINTK("Ignored sctp protocol event - state %d, "
962                                   "event_type %d, event_id %d\n",
963                                   state, event_type, subtype.chunk);
964                 break;
965
966         case SCTP_DISPOSITION_NOMEM:
967                 /* We ran out of memory, so we need to discard this
968                  * packet.
969                  */
970                 /* BUG--we should now recover some memory, probably by
971                  * reneging...
972                  */
973                 error = -ENOMEM;
974                 break;
975
976         case SCTP_DISPOSITION_DELETE_TCB:
977                 /* This should now be a command. */
978                 break;
979
980         case SCTP_DISPOSITION_CONSUME:
981         case SCTP_DISPOSITION_ABORT:
982                 /*
983                  * We should no longer have much work to do here as the
984                  * real work has been done as explicit commands above.
985                  */
986                 break;
987
988         case SCTP_DISPOSITION_VIOLATION:
989                 printk(KERN_ERR "sctp protocol violation state %d "
990                        "chunkid %d\n", state, subtype.chunk);
991                 break;
992
993         case SCTP_DISPOSITION_NOT_IMPL:
994                 printk(KERN_WARNING "sctp unimplemented feature in state %d, "
995                        "event_type %d, event_id %d\n",
996                        state, event_type, subtype.chunk);
997                 break;
998
999         case SCTP_DISPOSITION_BUG:
1000                 printk(KERN_ERR "sctp bug in state %d, "
1001                        "event_type %d, event_id %d\n",
1002                        state, event_type, subtype.chunk);
1003                 BUG();
1004                 break;
1005
1006         default:
1007                 printk(KERN_ERR "sctp impossible disposition %d "
1008                        "in state %d, event_type %d, event_id %d\n",
1009                        status, state, event_type, subtype.chunk);
1010                 BUG();
1011                 break;
1012         }
1013
1014 bail:
1015         return error;
1016 }
1017
1018 /********************************************************************
1019  * 2nd Level Abstractions
1020  ********************************************************************/
1021
1022 /* This is the side-effect interpreter.  */
1023 static int sctp_cmd_interpreter(sctp_event_t event_type,
1024                                 sctp_subtype_t subtype,
1025                                 sctp_state_t state,
1026                                 struct sctp_endpoint *ep,
1027                                 struct sctp_association *asoc,
1028                                 void *event_arg,
1029                                 sctp_disposition_t status,
1030                                 sctp_cmd_seq_t *commands,
1031                                 gfp_t gfp)
1032 {
1033         int error = 0;
1034         int force;
1035         sctp_cmd_t *cmd;
1036         struct sctp_chunk *new_obj;
1037         struct sctp_chunk *chunk = NULL;
1038         struct sctp_packet *packet;
1039         struct list_head *pos;
1040         struct timer_list *timer;
1041         unsigned long timeout;
1042         struct sctp_transport *t;
1043         struct sctp_sackhdr sackh;
1044         int local_cork = 0;
1045
1046         if (SCTP_EVENT_T_TIMEOUT != event_type)
1047                 chunk = (struct sctp_chunk *) event_arg;
1048
1049         /* Note:  This whole file is a huge candidate for rework.
1050          * For example, each command could either have its own handler, so
1051          * the loop would look like:
1052          *     while (cmds)
1053          *         cmd->handle(x, y, z)
1054          * --jgrimm
1055          */
1056         while (NULL != (cmd = sctp_next_cmd(commands))) {
1057                 switch (cmd->verb) {
1058                 case SCTP_CMD_NOP:
1059                         /* Do nothing. */
1060                         break;
1061
1062                 case SCTP_CMD_NEW_ASOC:
1063                         /* Register a new association.  */
1064                         if (local_cork) {
1065                                 sctp_outq_uncork(&asoc->outqueue);
1066                                 local_cork = 0;
1067                         }
1068                         asoc = cmd->obj.ptr;
1069                         /* Register with the endpoint.  */
1070                         sctp_endpoint_add_asoc(ep, asoc);
1071                         sctp_hash_established(asoc);
1072                         break;
1073
1074                 case SCTP_CMD_UPDATE_ASSOC:
1075                        sctp_assoc_update(asoc, cmd->obj.ptr);
1076                        break;
1077
1078                 case SCTP_CMD_PURGE_OUTQUEUE:
1079                        sctp_outq_teardown(&asoc->outqueue);
1080                        break;
1081
1082                 case SCTP_CMD_DELETE_TCB:
1083                         if (local_cork) {
1084                                 sctp_outq_uncork(&asoc->outqueue);
1085                                 local_cork = 0;
1086                         }
1087                         /* Delete the current association.  */
1088                         sctp_cmd_delete_tcb(commands, asoc);
1089                         asoc = NULL;
1090                         break;
1091
1092                 case SCTP_CMD_NEW_STATE:
1093                         /* Enter a new state.  */
1094                         sctp_cmd_new_state(commands, asoc, cmd->obj.state);
1095                         break;
1096
1097                 case SCTP_CMD_REPORT_TSN:
1098                         /* Record the arrival of a TSN.  */
1099                         sctp_tsnmap_mark(&asoc->peer.tsn_map, cmd->obj.u32);
1100                         break;
1101
1102                 case SCTP_CMD_REPORT_FWDTSN:
1103                         /* Move the Cumulattive TSN Ack ahead. */
1104                         sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32);
1105
1106                         /* Abort any in progress partial delivery. */
1107                         sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
1108                         break;
1109
1110                 case SCTP_CMD_PROCESS_FWDTSN:
1111                         sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.ptr);
1112                         break;
1113
1114                 case SCTP_CMD_GEN_SACK:
1115                         /* Generate a Selective ACK.
1116                          * The argument tells us whether to just count
1117                          * the packet and MAYBE generate a SACK, or
1118                          * force a SACK out.
1119                          */
1120                         force = cmd->obj.i32;
1121                         error = sctp_gen_sack(asoc, force, commands);
1122                         break;
1123
1124                 case SCTP_CMD_PROCESS_SACK:
1125                         /* Process an inbound SACK.  */
1126                         error = sctp_cmd_process_sack(commands, asoc,
1127                                                       cmd->obj.ptr);
1128                         break;
1129
1130                 case SCTP_CMD_GEN_INIT_ACK:
1131                         /* Generate an INIT ACK chunk.  */
1132                         new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC,
1133                                                      0);
1134                         if (!new_obj)
1135                                 goto nomem;
1136
1137                         sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1138                                         SCTP_CHUNK(new_obj));
1139                         break;
1140
1141                 case SCTP_CMD_PEER_INIT:
1142                         /* Process a unified INIT from the peer.
1143                          * Note: Only used during INIT-ACK processing.  If
1144                          * there is an error just return to the outter
1145                          * layer which will bail.
1146                          */
1147                         error = sctp_cmd_process_init(commands, asoc, chunk,
1148                                                       cmd->obj.ptr, gfp);
1149                         break;
1150
1151                 case SCTP_CMD_GEN_COOKIE_ECHO:
1152                         /* Generate a COOKIE ECHO chunk.  */
1153                         new_obj = sctp_make_cookie_echo(asoc, chunk);
1154                         if (!new_obj) {
1155                                 if (cmd->obj.ptr)
1156                                         sctp_chunk_free(cmd->obj.ptr);
1157                                 goto nomem;
1158                         }
1159                         sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1160                                         SCTP_CHUNK(new_obj));
1161
1162                         /* If there is an ERROR chunk to be sent along with
1163                          * the COOKIE_ECHO, send it, too.
1164                          */
1165                         if (cmd->obj.ptr)
1166                                 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1167                                                 SCTP_CHUNK(cmd->obj.ptr));
1168
1169                         /* FIXME - Eventually come up with a cleaner way to
1170                          * enabling COOKIE-ECHO + DATA bundling during
1171                          * multihoming stale cookie scenarios, the following
1172                          * command plays with asoc->peer.retran_path to
1173                          * avoid the problem of sending the COOKIE-ECHO and
1174                          * DATA in different paths, which could result
1175                          * in the association being ABORTed if the DATA chunk
1176                          * is processed first by the server.  Checking the
1177                          * init error counter simply causes this command
1178                          * to be executed only during failed attempts of
1179                          * association establishment.
1180                          */
1181                         if ((asoc->peer.retran_path !=
1182                              asoc->peer.primary_path) &&
1183                             (asoc->init_err_counter > 0)) {
1184                                 sctp_add_cmd_sf(commands,
1185                                                 SCTP_CMD_FORCE_PRIM_RETRAN,
1186                                                 SCTP_NULL());
1187                         }
1188
1189                         break;
1190
1191                 case SCTP_CMD_GEN_SHUTDOWN:
1192                         /* Generate SHUTDOWN when in SHUTDOWN_SENT state.
1193                          * Reset error counts.
1194                          */
1195                         asoc->overall_error_count = 0;
1196
1197                         /* Generate a SHUTDOWN chunk.  */
1198                         new_obj = sctp_make_shutdown(asoc, chunk);
1199                         if (!new_obj)
1200                                 goto nomem;
1201                         sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1202                                         SCTP_CHUNK(new_obj));
1203                         break;
1204
1205                 case SCTP_CMD_CHUNK_ULP:
1206                         /* Send a chunk to the sockets layer.  */
1207                         SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1208                                           "chunk_up:", cmd->obj.ptr,
1209                                           "ulpq:", &asoc->ulpq);
1210                         sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.ptr,
1211                                             GFP_ATOMIC);
1212                         break;
1213
1214                 case SCTP_CMD_EVENT_ULP:
1215                         /* Send a notification to the sockets layer.  */
1216                         SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1217                                           "event_up:",cmd->obj.ptr,
1218                                           "ulpq:",&asoc->ulpq);
1219                         sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ptr);
1220                         break;
1221
1222                 case SCTP_CMD_REPLY:
1223                         /* If an caller has not already corked, do cork. */
1224                         if (!asoc->outqueue.cork) {
1225                                 sctp_outq_cork(&asoc->outqueue);
1226                                 local_cork = 1;
1227                         }
1228                         /* Send a chunk to our peer.  */
1229                         error = sctp_outq_tail(&asoc->outqueue, cmd->obj.ptr);
1230                         break;
1231
1232                 case SCTP_CMD_SEND_PKT:
1233                         /* Send a full packet to our peer.  */
1234                         packet = cmd->obj.ptr;
1235                         sctp_packet_transmit(packet);
1236                         sctp_ootb_pkt_free(packet);
1237                         break;
1238
1239                 case SCTP_CMD_RETRAN:
1240                         /* Mark a transport for retransmission.  */
1241                         sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1242                                         SCTP_RTXR_T3_RTX);
1243                         break;
1244
1245                 case SCTP_CMD_TRANSMIT:
1246                         /* Kick start transmission. */
1247                         error = sctp_outq_uncork(&asoc->outqueue);
1248                         local_cork = 0;
1249                         break;
1250
1251                 case SCTP_CMD_ECN_CE:
1252                         /* Do delayed CE processing.   */
1253                         sctp_do_ecn_ce_work(asoc, cmd->obj.u32);
1254                         break;
1255
1256                 case SCTP_CMD_ECN_ECNE:
1257                         /* Do delayed ECNE processing. */
1258                         new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32,
1259                                                         chunk);
1260                         if (new_obj)
1261                                 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1262                                                 SCTP_CHUNK(new_obj));
1263                         break;
1264
1265                 case SCTP_CMD_ECN_CWR:
1266                         /* Do delayed CWR processing.  */
1267                         sctp_do_ecn_cwr_work(asoc, cmd->obj.u32);
1268                         break;
1269
1270                 case SCTP_CMD_SETUP_T2:
1271                         sctp_cmd_setup_t2(commands, asoc, cmd->obj.ptr);
1272                         break;
1273
1274                 case SCTP_CMD_TIMER_START:
1275                         timer = &asoc->timers[cmd->obj.to];
1276                         timeout = asoc->timeouts[cmd->obj.to];
1277                         BUG_ON(!timeout);
1278
1279                         timer->expires = jiffies + timeout;
1280                         sctp_association_hold(asoc);
1281                         add_timer(timer);
1282                         break;
1283
1284                 case SCTP_CMD_TIMER_RESTART:
1285                         timer = &asoc->timers[cmd->obj.to];
1286                         timeout = asoc->timeouts[cmd->obj.to];
1287                         if (!mod_timer(timer, jiffies + timeout))
1288                                 sctp_association_hold(asoc);
1289                         break;
1290
1291                 case SCTP_CMD_TIMER_STOP:
1292                         timer = &asoc->timers[cmd->obj.to];
1293                         if (timer_pending(timer) && del_timer(timer))
1294                                 sctp_association_put(asoc);
1295                         break;
1296
1297                 case SCTP_CMD_INIT_CHOOSE_TRANSPORT:
1298                         chunk = cmd->obj.ptr;
1299                         t = sctp_assoc_choose_init_transport(asoc);
1300                         asoc->init_last_sent_to = t;
1301                         chunk->transport = t;
1302                         t->init_sent_count++;
1303                         break;
1304
1305                 case SCTP_CMD_INIT_RESTART:
1306                         /* Do the needed accounting and updates
1307                          * associated with restarting an initialization
1308                          * timer. Only multiply the timeout by two if
1309                          * all transports have been tried at the current
1310                          * timeout.
1311                          */
1312                         t = asoc->init_last_sent_to;
1313                         asoc->init_err_counter++;
1314
1315                         if (t->init_sent_count > (asoc->init_cycle + 1)) {
1316                                 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] *= 2;
1317                                 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] >
1318                                     asoc->max_init_timeo) {
1319                                         asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
1320                                                 asoc->max_init_timeo;
1321                                 }
1322                                 asoc->init_cycle++;
1323                                 SCTP_DEBUG_PRINTK(
1324                                         "T1 INIT Timeout adjustment"
1325                                         " init_err_counter: %d"
1326                                         " cycle: %d"
1327                                         " timeout: %ld\n",
1328                                         asoc->init_err_counter,
1329                                         asoc->init_cycle,
1330                                         asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT]);
1331                         }
1332
1333                         sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
1334                                         SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
1335                         break;
1336
1337                 case SCTP_CMD_COOKIEECHO_RESTART:
1338                         /* Do the needed accounting and updates
1339                          * associated with restarting an initialization
1340                          * timer. Only multiply the timeout by two if
1341                          * all transports have been tried at the current
1342                          * timeout.
1343                          */
1344                         asoc->init_err_counter++;
1345
1346                         asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] *= 2;
1347                         if (asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] >
1348                             asoc->max_init_timeo) {
1349                                 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
1350                                         asoc->max_init_timeo;
1351                         }
1352                         SCTP_DEBUG_PRINTK(
1353                                 "T1 COOKIE Timeout adjustment"
1354                                 " init_err_counter: %d"
1355                                 " timeout: %ld\n",
1356                                 asoc->init_err_counter,
1357                                 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE]);
1358
1359                         /* If we've sent any data bundled with
1360                          * COOKIE-ECHO we need to resend.
1361                          */
1362                         list_for_each(pos, &asoc->peer.transport_addr_list) {
1363                                 t = list_entry(pos, struct sctp_transport,
1364                                                transports);
1365                                 sctp_retransmit_mark(&asoc->outqueue, t, 0);
1366                         }
1367
1368                         sctp_add_cmd_sf(commands,
1369                                         SCTP_CMD_TIMER_RESTART,
1370                                         SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
1371                         break;
1372
1373                 case SCTP_CMD_INIT_FAILED:
1374                         sctp_cmd_init_failed(commands, asoc, cmd->obj.err);
1375                         break;
1376
1377                 case SCTP_CMD_ASSOC_FAILED:
1378                         sctp_cmd_assoc_failed(commands, asoc, event_type,
1379                                               subtype, chunk, cmd->obj.err);
1380                         break;
1381
1382                 case SCTP_CMD_INIT_COUNTER_INC:
1383                         asoc->init_err_counter++;
1384                         break;
1385
1386                 case SCTP_CMD_INIT_COUNTER_RESET:
1387                         asoc->init_err_counter = 0;
1388                         asoc->init_cycle = 0;
1389                         break;
1390
1391                 case SCTP_CMD_REPORT_DUP:
1392                         sctp_tsnmap_mark_dup(&asoc->peer.tsn_map,
1393                                              cmd->obj.u32);
1394                         break;
1395
1396                 case SCTP_CMD_REPORT_BAD_TAG:
1397                         SCTP_DEBUG_PRINTK("vtag mismatch!\n");
1398                         break;
1399
1400                 case SCTP_CMD_STRIKE:
1401                         /* Mark one strike against a transport.  */
1402                         sctp_do_8_2_transport_strike(asoc, cmd->obj.transport);
1403                         break;
1404
1405                 case SCTP_CMD_TRANSPORT_RESET:
1406                         t = cmd->obj.transport;
1407                         sctp_cmd_transport_reset(commands, asoc, t);
1408                         break;
1409
1410                 case SCTP_CMD_TRANSPORT_ON:
1411                         t = cmd->obj.transport;
1412                         sctp_cmd_transport_on(commands, asoc, t, chunk);
1413                         break;
1414
1415                 case SCTP_CMD_HB_TIMERS_START:
1416                         sctp_cmd_hb_timers_start(commands, asoc);
1417                         break;
1418
1419                 case SCTP_CMD_HB_TIMER_UPDATE:
1420                         t = cmd->obj.transport;
1421                         sctp_cmd_hb_timer_update(commands, asoc, t);
1422                         break;
1423
1424                 case SCTP_CMD_HB_TIMERS_STOP:
1425                         sctp_cmd_hb_timers_stop(commands, asoc);
1426                         break;
1427
1428                 case SCTP_CMD_REPORT_ERROR:
1429                         error = cmd->obj.error;
1430                         break;
1431
1432                 case SCTP_CMD_PROCESS_CTSN:
1433                         /* Dummy up a SACK for processing. */
1434                         sackh.cum_tsn_ack = cmd->obj.be32;
1435                         sackh.a_rwnd = 0;
1436                         sackh.num_gap_ack_blocks = 0;
1437                         sackh.num_dup_tsns = 0;
1438                         sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK,
1439                                         SCTP_SACKH(&sackh));
1440                         break;
1441
1442                 case SCTP_CMD_DISCARD_PACKET:
1443                         /* We need to discard the whole packet.  */
1444                         chunk->pdiscard = 1;
1445                         break;
1446
1447                 case SCTP_CMD_RTO_PENDING:
1448                         t = cmd->obj.transport;
1449                         t->rto_pending = 1;
1450                         break;
1451
1452                 case SCTP_CMD_PART_DELIVER:
1453                         sctp_ulpq_partial_delivery(&asoc->ulpq, cmd->obj.ptr,
1454                                                    GFP_ATOMIC);
1455                         break;
1456
1457                 case SCTP_CMD_RENEGE:
1458                         sctp_ulpq_renege(&asoc->ulpq, cmd->obj.ptr,
1459                                          GFP_ATOMIC);
1460                         break;
1461
1462                 case SCTP_CMD_SETUP_T4:
1463                         sctp_cmd_setup_t4(commands, asoc, cmd->obj.ptr);
1464                         break;
1465
1466                 case SCTP_CMD_PROCESS_OPERR:
1467                         sctp_cmd_process_operr(commands, asoc, chunk);
1468                         break;
1469                 case SCTP_CMD_CLEAR_INIT_TAG:
1470                         asoc->peer.i.init_tag = 0;
1471                         break;
1472                 case SCTP_CMD_DEL_NON_PRIMARY:
1473                         sctp_cmd_del_non_primary(asoc);
1474                         break;
1475                 case SCTP_CMD_T3_RTX_TIMERS_STOP:
1476                         sctp_cmd_t3_rtx_timers_stop(commands, asoc);
1477                         break;
1478                 case SCTP_CMD_FORCE_PRIM_RETRAN:
1479                         t = asoc->peer.retran_path;
1480                         asoc->peer.retran_path = asoc->peer.primary_path;
1481                         error = sctp_outq_uncork(&asoc->outqueue);
1482                         local_cork = 0;
1483                         asoc->peer.retran_path = t;
1484                         break;
1485                 case SCTP_CMD_SET_SK_ERR:
1486                         sctp_cmd_set_sk_err(asoc, cmd->obj.error);
1487                         break;
1488                 default:
1489                         printk(KERN_WARNING "Impossible command: %u, %p\n",
1490                                cmd->verb, cmd->obj.ptr);
1491                         break;
1492                 }
1493
1494                 if (error)
1495                         break;
1496         }
1497
1498 out:
1499         if (local_cork)
1500                 sctp_outq_uncork(&asoc->outqueue);
1501         return error;
1502 nomem:
1503         error = -ENOMEM;
1504         goto out;
1505 }
1506