[SCTP]: Switch ->cmp_addr() and sctp_cmp_addr_exact() to net-endian.
[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                 error = sctp_outq_tail(&asoc->outqueue, 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_h),
445                                          transport->ipaddr_h.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,
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         event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
496                                                 (__u16)error, 0, 0,
497                                                 GFP_ATOMIC);
498         if (event)
499                 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
500                                 SCTP_ULPEVENT(event));
501
502         sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
503                         SCTP_STATE(SCTP_STATE_CLOSED));
504
505         /* SEND_FAILED sent later when cleaning up the association. */
506         asoc->outqueue.error = error;
507         sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
508 }
509
510 /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT
511  * inside the cookie.  In reality, this is only used for INIT-ACK processing
512  * since all other cases use "temporary" associations and can do all
513  * their work in statefuns directly.
514  */
515 static int sctp_cmd_process_init(sctp_cmd_seq_t *commands,
516                                  struct sctp_association *asoc,
517                                  struct sctp_chunk *chunk,
518                                  sctp_init_chunk_t *peer_init,
519                                  gfp_t gfp)
520 {
521         int error;
522
523         /* We only process the init as a sideeffect in a single
524          * case.   This is when we process the INIT-ACK.   If we
525          * fail during INIT processing (due to malloc problems),
526          * just return the error and stop processing the stack.
527          */
528         if (!sctp_process_init(asoc, chunk->chunk_hdr->type,
529                                sctp_source(chunk), peer_init, gfp))
530                 error = -ENOMEM;
531         else
532                 error = 0;
533
534         return error;
535 }
536
537 /* Helper function to break out starting up of heartbeat timers.  */
538 static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds,
539                                      struct sctp_association *asoc)
540 {
541         struct sctp_transport *t;
542         struct list_head *pos;
543
544         /* Start a heartbeat timer for each transport on the association.
545          * hold a reference on the transport to make sure none of
546          * the needed data structures go away.
547          */
548         list_for_each(pos, &asoc->peer.transport_addr_list) {
549                 t = list_entry(pos, struct sctp_transport, transports);
550
551                 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
552                         sctp_transport_hold(t);
553         }
554 }
555
556 static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds,
557                                     struct sctp_association *asoc)
558 {
559         struct sctp_transport *t;
560         struct list_head *pos;
561
562         /* Stop all heartbeat timers. */
563
564         list_for_each(pos, &asoc->peer.transport_addr_list) {
565                 t = list_entry(pos, struct sctp_transport, transports);
566                 if (del_timer(&t->hb_timer))
567                         sctp_transport_put(t);
568         }
569 }
570
571 /* Helper function to stop any pending T3-RTX timers */
572 static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds,
573                                         struct sctp_association *asoc)
574 {
575         struct sctp_transport *t;
576         struct list_head *pos;
577
578         list_for_each(pos, &asoc->peer.transport_addr_list) {
579                 t = list_entry(pos, struct sctp_transport, transports);
580                 if (timer_pending(&t->T3_rtx_timer) &&
581                     del_timer(&t->T3_rtx_timer)) {
582                         sctp_transport_put(t);
583                 }
584         }
585 }
586
587
588 /* Helper function to update the heartbeat timer. */
589 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds,
590                                      struct sctp_association *asoc,
591                                      struct sctp_transport *t)
592 {
593         /* Update the heartbeat timer.  */
594         if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
595                 sctp_transport_hold(t);
596 }
597
598 /* Helper function to handle the reception of an HEARTBEAT ACK.  */
599 static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds,
600                                   struct sctp_association *asoc,
601                                   struct sctp_transport *t,
602                                   struct sctp_chunk *chunk)
603 {
604         sctp_sender_hb_info_t *hbinfo;
605
606         /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the
607          * HEARTBEAT should clear the error counter of the destination
608          * transport address to which the HEARTBEAT was sent.
609          * The association's overall error count is also cleared.
610          */
611         t->error_count = 0;
612         t->asoc->overall_error_count = 0;
613
614         /* Mark the destination transport address as active if it is not so
615          * marked.
616          */
617         if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED))
618                 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
619                                              SCTP_HEARTBEAT_SUCCESS);
620
621         /* The receiver of the HEARTBEAT ACK should also perform an
622          * RTT measurement for that destination transport address
623          * using the time value carried in the HEARTBEAT ACK chunk.
624          */
625         hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data;
626         sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at));
627
628         /* Update the heartbeat timer.  */
629         if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
630                 sctp_transport_hold(t);
631 }
632
633 /* Helper function to do a transport reset at the expiry of the hearbeat
634  * timer.
635  */
636 static void sctp_cmd_transport_reset(sctp_cmd_seq_t *cmds,
637                                      struct sctp_association *asoc,
638                                      struct sctp_transport *t)
639 {
640         sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE);
641
642         /* Mark one strike against a transport.  */
643         sctp_do_8_2_transport_strike(asoc, t);
644 }
645
646 /* Helper function to process the process SACK command.  */
647 static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds,
648                                  struct sctp_association *asoc,
649                                  struct sctp_sackhdr *sackh)
650 {
651         int err;
652
653         if (sctp_outq_sack(&asoc->outqueue, sackh)) {
654                 /* There are no more TSNs awaiting SACK.  */
655                 err = sctp_do_sm(SCTP_EVENT_T_OTHER,
656                                  SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN),
657                                  asoc->state, asoc->ep, asoc, NULL,
658                                  GFP_ATOMIC);
659         } else {
660                 /* Windows may have opened, so we need
661                  * to check if we have DATA to transmit
662                  */
663                 err = sctp_outq_flush(&asoc->outqueue, 0);
664         }
665
666         return err;
667 }
668
669 /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set
670  * the transport for a shutdown chunk.
671  */
672 static void sctp_cmd_setup_t2(sctp_cmd_seq_t *cmds, 
673                               struct sctp_association *asoc,
674                               struct sctp_chunk *chunk)
675 {
676         struct sctp_transport *t;
677
678         t = sctp_assoc_choose_shutdown_transport(asoc);
679         asoc->shutdown_last_sent_to = t;
680         asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto;
681         chunk->transport = t;
682 }
683
684 /* Helper function to change the state of an association. */
685 static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds, 
686                                struct sctp_association *asoc,
687                                sctp_state_t state)
688 {
689         struct sock *sk = asoc->base.sk;
690
691         asoc->state = state;
692
693         SCTP_DEBUG_PRINTK("sctp_cmd_new_state: asoc %p[%s]\n",
694                           asoc, sctp_state_tbl[state]);
695
696         if (sctp_style(sk, TCP)) {
697                 /* Change the sk->sk_state of a TCP-style socket that has
698                  * sucessfully completed a connect() call.
699                  */
700                 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED))
701                         sk->sk_state = SCTP_SS_ESTABLISHED;
702
703                 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */
704                 if (sctp_state(asoc, SHUTDOWN_RECEIVED) &&
705                     sctp_sstate(sk, ESTABLISHED))
706                         sk->sk_shutdown |= RCV_SHUTDOWN;
707         }
708
709         if (sctp_state(asoc, COOKIE_WAIT)) {
710                 /* Reset init timeouts since they may have been
711                  * increased due to timer expirations.
712                  */
713                 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
714                                                 asoc->rto_initial;
715                 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
716                                                 asoc->rto_initial;
717         }
718
719         if (sctp_state(asoc, ESTABLISHED) ||
720             sctp_state(asoc, CLOSED) ||
721             sctp_state(asoc, SHUTDOWN_RECEIVED)) {
722                 /* Wake up any processes waiting in the asoc's wait queue in
723                  * sctp_wait_for_connect() or sctp_wait_for_sndbuf().
724                  */
725                 if (waitqueue_active(&asoc->wait))
726                         wake_up_interruptible(&asoc->wait);
727
728                 /* Wake up any processes waiting in the sk's sleep queue of
729                  * a TCP-style or UDP-style peeled-off socket in
730                  * sctp_wait_for_accept() or sctp_wait_for_packet().
731                  * For a UDP-style socket, the waiters are woken up by the
732                  * notifications.
733                  */
734                 if (!sctp_style(sk, UDP))
735                         sk->sk_state_change(sk);
736         }
737 }
738
739 /* Helper function to delete an association. */
740 static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds,
741                                 struct sctp_association *asoc)
742 {
743         struct sock *sk = asoc->base.sk;
744
745         /* If it is a non-temporary association belonging to a TCP-style
746          * listening socket that is not closed, do not free it so that accept() 
747          * can pick it up later.
748          */ 
749         if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) &&
750             (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK))
751                 return;
752
753         sctp_unhash_established(asoc);
754         sctp_association_free(asoc);
755 }
756
757 /*
758  * ADDIP Section 4.1 ASCONF Chunk Procedures
759  * A4) Start a T-4 RTO timer, using the RTO value of the selected
760  * destination address (we use active path instead of primary path just
761  * because primary path may be inactive. 
762  */
763 static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds,
764                                 struct sctp_association *asoc,
765                                 struct sctp_chunk *chunk)
766 {
767         struct sctp_transport *t;
768
769         t = asoc->peer.active_path;
770         asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto;
771         chunk->transport = t;
772 }
773
774 /* Process an incoming Operation Error Chunk. */ 
775 static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds,
776                                    struct sctp_association *asoc,
777                                    struct sctp_chunk *chunk)
778 {
779         struct sctp_operr_chunk *operr_chunk;
780         struct sctp_errhdr *err_hdr;
781
782         operr_chunk = (struct sctp_operr_chunk *)chunk->chunk_hdr;
783         err_hdr = &operr_chunk->err_hdr;
784
785         switch (err_hdr->cause) {
786         case SCTP_ERROR_UNKNOWN_CHUNK:
787         {
788                 struct sctp_chunkhdr *unk_chunk_hdr;
789
790                 unk_chunk_hdr = (struct sctp_chunkhdr *)err_hdr->variable;
791                 switch (unk_chunk_hdr->type) {
792                 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with an
793                  * ERROR chunk reporting that it did not recognized the ASCONF
794                  * chunk type, the sender of the ASCONF MUST NOT send any
795                  * further ASCONF chunks and MUST stop its T-4 timer.
796                  */
797                 case SCTP_CID_ASCONF:
798                         asoc->peer.asconf_capable = 0;
799                         sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP,
800                                         SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
801                         break;
802                 default:
803                         break;
804                 }
805                 break;
806         }
807         default:
808                 break;
809         }
810 }
811
812 /* Process variable FWDTSN chunk information. */
813 static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq, 
814                                     struct sctp_chunk *chunk)
815 {
816         struct sctp_fwdtsn_skip *skip;
817         /* Walk through all the skipped SSNs */
818         sctp_walk_fwdtsn(skip, chunk) {
819                 sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn));
820         }
821
822         return;
823 }
824
825 /* Helper function to remove the association non-primary peer 
826  * transports.
827  */ 
828 static void sctp_cmd_del_non_primary(struct sctp_association *asoc)
829 {
830         struct sctp_transport *t;
831         struct list_head *pos;
832         struct list_head *temp;
833         union sctp_addr tmp;
834         flip_to_n(&tmp, &asoc->peer.primary_addr);
835
836         list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
837                 t = list_entry(pos, struct sctp_transport, transports);
838                 if (!sctp_cmp_addr_exact(&t->ipaddr,
839                                          &tmp)) {
840                         sctp_assoc_del_peer(asoc, &t->ipaddr_h);
841                 }
842         }
843
844         return;
845 }
846
847 /* Helper function to set sk_err on a 1-1 style socket. */
848 static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error)
849 {
850         struct sock *sk = asoc->base.sk;
851
852         if (!sctp_style(sk, UDP))
853                 sk->sk_err = error;
854 }
855
856 /* These three macros allow us to pull the debugging code out of the
857  * main flow of sctp_do_sm() to keep attention focused on the real
858  * functionality there.
859  */
860 #define DEBUG_PRE \
861         SCTP_DEBUG_PRINTK("sctp_do_sm prefn: " \
862                           "ep %p, %s, %s, asoc %p[%s], %s\n", \
863                           ep, sctp_evttype_tbl[event_type], \
864                           (*debug_fn)(subtype), asoc, \
865                           sctp_state_tbl[state], state_fn->name)
866
867 #define DEBUG_POST \
868         SCTP_DEBUG_PRINTK("sctp_do_sm postfn: " \
869                           "asoc %p, status: %s\n", \
870                           asoc, sctp_status_tbl[status])
871
872 #define DEBUG_POST_SFX \
873         SCTP_DEBUG_PRINTK("sctp_do_sm post sfx: error %d, asoc %p[%s]\n", \
874                           error, asoc, \
875                           sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \
876                           sctp_assoc2id(asoc)))?asoc->state:SCTP_STATE_CLOSED])
877
878 /*
879  * This is the master state machine processing function.
880  *
881  * If you want to understand all of lksctp, this is a
882  * good place to start.
883  */
884 int sctp_do_sm(sctp_event_t event_type, sctp_subtype_t subtype,
885                sctp_state_t state,
886                struct sctp_endpoint *ep,
887                struct sctp_association *asoc,
888                void *event_arg,
889                gfp_t gfp)
890 {
891         sctp_cmd_seq_t commands;
892         const sctp_sm_table_entry_t *state_fn;
893         sctp_disposition_t status;
894         int error = 0;
895         typedef const char *(printfn_t)(sctp_subtype_t);
896
897         static printfn_t *table[] = {
898                 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname,
899         };
900         printfn_t *debug_fn  __attribute__ ((unused)) = table[event_type];
901
902         /* Look up the state function, run it, and then process the
903          * side effects.  These three steps are the heart of lksctp.
904          */
905         state_fn = sctp_sm_lookup_event(event_type, state, subtype);
906
907         sctp_init_cmd_seq(&commands);
908
909         DEBUG_PRE;
910         status = (*state_fn->fn)(ep, asoc, subtype, event_arg, &commands);
911         DEBUG_POST;
912
913         error = sctp_side_effects(event_type, subtype, state,
914                                   ep, asoc, event_arg, status, 
915                                   &commands, gfp);
916         DEBUG_POST_SFX;
917
918         return error;
919 }
920
921 #undef DEBUG_PRE
922 #undef DEBUG_POST
923
924 /*****************************************************************
925  * This the master state function side effect processing function.
926  *****************************************************************/
927 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
928                              sctp_state_t state,
929                              struct sctp_endpoint *ep,
930                              struct sctp_association *asoc,
931                              void *event_arg,
932                              sctp_disposition_t status,
933                              sctp_cmd_seq_t *commands,
934                              gfp_t gfp)
935 {
936         int error;
937
938         /* FIXME - Most of the dispositions left today would be categorized
939          * as "exceptional" dispositions.  For those dispositions, it
940          * may not be proper to run through any of the commands at all.
941          * For example, the command interpreter might be run only with
942          * disposition SCTP_DISPOSITION_CONSUME.
943          */
944         if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state,
945                                                ep, asoc,
946                                                event_arg, status,
947                                                commands, gfp)))
948                 goto bail;
949
950         switch (status) {
951         case SCTP_DISPOSITION_DISCARD:
952                 SCTP_DEBUG_PRINTK("Ignored sctp protocol event - state %d, "
953                                   "event_type %d, event_id %d\n",
954                                   state, event_type, subtype.chunk);
955                 break;
956
957         case SCTP_DISPOSITION_NOMEM:
958                 /* We ran out of memory, so we need to discard this
959                  * packet.
960                  */
961                 /* BUG--we should now recover some memory, probably by
962                  * reneging...
963                  */
964                 error = -ENOMEM;
965                 break;
966
967         case SCTP_DISPOSITION_DELETE_TCB:
968                 /* This should now be a command. */
969                 break;
970
971         case SCTP_DISPOSITION_CONSUME:
972         case SCTP_DISPOSITION_ABORT:
973                 /*
974                  * We should no longer have much work to do here as the
975                  * real work has been done as explicit commands above.
976                  */
977                 break;
978
979         case SCTP_DISPOSITION_VIOLATION:
980                 printk(KERN_ERR "sctp protocol violation state %d "
981                        "chunkid %d\n", state, subtype.chunk);
982                 break;
983
984         case SCTP_DISPOSITION_NOT_IMPL:
985                 printk(KERN_WARNING "sctp unimplemented feature in state %d, "
986                        "event_type %d, event_id %d\n",
987                        state, event_type, subtype.chunk);
988                 break;
989
990         case SCTP_DISPOSITION_BUG:
991                 printk(KERN_ERR "sctp bug in state %d, "
992                        "event_type %d, event_id %d\n",
993                        state, event_type, subtype.chunk);
994                 BUG();
995                 break;
996
997         default:
998                 printk(KERN_ERR "sctp impossible disposition %d "
999                        "in state %d, event_type %d, event_id %d\n",
1000                        status, state, event_type, subtype.chunk);
1001                 BUG();
1002                 break;
1003         };
1004
1005 bail:
1006         return error;
1007 }
1008
1009 /********************************************************************
1010  * 2nd Level Abstractions
1011  ********************************************************************/
1012
1013 /* This is the side-effect interpreter.  */
1014 static int sctp_cmd_interpreter(sctp_event_t event_type,
1015                                 sctp_subtype_t subtype,
1016                                 sctp_state_t state,
1017                                 struct sctp_endpoint *ep,
1018                                 struct sctp_association *asoc,
1019                                 void *event_arg,
1020                                 sctp_disposition_t status,
1021                                 sctp_cmd_seq_t *commands,
1022                                 gfp_t gfp)
1023 {
1024         int error = 0;
1025         int force;
1026         sctp_cmd_t *cmd;
1027         struct sctp_chunk *new_obj;
1028         struct sctp_chunk *chunk = NULL;
1029         struct sctp_packet *packet;
1030         struct list_head *pos;
1031         struct timer_list *timer;
1032         unsigned long timeout;
1033         struct sctp_transport *t;
1034         struct sctp_sackhdr sackh;
1035         int local_cork = 0;
1036
1037         if (SCTP_EVENT_T_TIMEOUT != event_type)
1038                 chunk = (struct sctp_chunk *) event_arg;
1039
1040         /* Note:  This whole file is a huge candidate for rework.
1041          * For example, each command could either have its own handler, so
1042          * the loop would look like:
1043          *     while (cmds)
1044          *         cmd->handle(x, y, z)
1045          * --jgrimm
1046          */
1047         while (NULL != (cmd = sctp_next_cmd(commands))) {
1048                 switch (cmd->verb) {
1049                 case SCTP_CMD_NOP:
1050                         /* Do nothing. */
1051                         break;
1052
1053                 case SCTP_CMD_NEW_ASOC:
1054                         /* Register a new association.  */
1055                         if (local_cork) {
1056                                 sctp_outq_uncork(&asoc->outqueue); 
1057                                 local_cork = 0;
1058                         }
1059                         asoc = cmd->obj.ptr;
1060                         /* Register with the endpoint.  */
1061                         sctp_endpoint_add_asoc(ep, asoc);
1062                         sctp_hash_established(asoc);
1063                         break;
1064
1065                 case SCTP_CMD_UPDATE_ASSOC:
1066                        sctp_assoc_update(asoc, cmd->obj.ptr);
1067                        break;
1068
1069                 case SCTP_CMD_PURGE_OUTQUEUE:
1070                        sctp_outq_teardown(&asoc->outqueue);
1071                        break;
1072
1073                 case SCTP_CMD_DELETE_TCB:                       
1074                         if (local_cork) {
1075                                 sctp_outq_uncork(&asoc->outqueue);
1076                                 local_cork = 0;
1077                         }
1078                         /* Delete the current association.  */
1079                         sctp_cmd_delete_tcb(commands, asoc);
1080                         asoc = NULL;
1081                         break;
1082
1083                 case SCTP_CMD_NEW_STATE:
1084                         /* Enter a new state.  */
1085                         sctp_cmd_new_state(commands, asoc, cmd->obj.state);
1086                         break;
1087
1088                 case SCTP_CMD_REPORT_TSN:
1089                         /* Record the arrival of a TSN.  */
1090                         sctp_tsnmap_mark(&asoc->peer.tsn_map, cmd->obj.u32);
1091                         break;
1092
1093                 case SCTP_CMD_REPORT_FWDTSN:
1094                         /* Move the Cumulattive TSN Ack ahead. */
1095                         sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32);
1096
1097                         /* Abort any in progress partial delivery. */
1098                         sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
1099                         break;
1100
1101                 case SCTP_CMD_PROCESS_FWDTSN:
1102                         sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.ptr);
1103                         break;
1104
1105                 case SCTP_CMD_GEN_SACK:
1106                         /* Generate a Selective ACK.
1107                          * The argument tells us whether to just count
1108                          * the packet and MAYBE generate a SACK, or
1109                          * force a SACK out.
1110                          */
1111                         force = cmd->obj.i32;
1112                         error = sctp_gen_sack(asoc, force, commands);
1113                         break;
1114
1115                 case SCTP_CMD_PROCESS_SACK:
1116                         /* Process an inbound SACK.  */
1117                         error = sctp_cmd_process_sack(commands, asoc,
1118                                                       cmd->obj.ptr);
1119                         break;
1120
1121                 case SCTP_CMD_GEN_INIT_ACK:
1122                         /* Generate an INIT ACK chunk.  */
1123                         new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC,
1124                                                      0);
1125                         if (!new_obj)
1126                                 goto nomem;
1127
1128                         sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1129                                         SCTP_CHUNK(new_obj));
1130                         break;
1131
1132                 case SCTP_CMD_PEER_INIT:
1133                         /* Process a unified INIT from the peer.
1134                          * Note: Only used during INIT-ACK processing.  If
1135                          * there is an error just return to the outter
1136                          * layer which will bail.
1137                          */
1138                         error = sctp_cmd_process_init(commands, asoc, chunk,
1139                                                       cmd->obj.ptr, gfp);
1140                         break;
1141
1142                 case SCTP_CMD_GEN_COOKIE_ECHO:
1143                         /* Generate a COOKIE ECHO chunk.  */
1144                         new_obj = sctp_make_cookie_echo(asoc, chunk);
1145                         if (!new_obj) {
1146                                 if (cmd->obj.ptr)
1147                                         sctp_chunk_free(cmd->obj.ptr);
1148                                 goto nomem;
1149                         }
1150                         sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1151                                         SCTP_CHUNK(new_obj));
1152
1153                         /* If there is an ERROR chunk to be sent along with
1154                          * the COOKIE_ECHO, send it, too.
1155                          */
1156                         if (cmd->obj.ptr)
1157                                 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1158                                                 SCTP_CHUNK(cmd->obj.ptr));
1159
1160                         /* FIXME - Eventually come up with a cleaner way to
1161                          * enabling COOKIE-ECHO + DATA bundling during 
1162                          * multihoming stale cookie scenarios, the following 
1163                          * command plays with asoc->peer.retran_path to 
1164                          * avoid the problem of sending the COOKIE-ECHO and 
1165                          * DATA in different paths, which could result 
1166                          * in the association being ABORTed if the DATA chunk 
1167                          * is processed first by the server.  Checking the
1168                          * init error counter simply causes this command
1169                          * to be executed only during failed attempts of
1170                          * association establishment.
1171                          */
1172                         if ((asoc->peer.retran_path !=
1173                              asoc->peer.primary_path) &&
1174                             (asoc->init_err_counter > 0)) {
1175                                 sctp_add_cmd_sf(commands,
1176                                                 SCTP_CMD_FORCE_PRIM_RETRAN,
1177                                                 SCTP_NULL());
1178                         }
1179
1180                         break;
1181
1182                 case SCTP_CMD_GEN_SHUTDOWN:
1183                         /* Generate SHUTDOWN when in SHUTDOWN_SENT state.
1184                          * Reset error counts.
1185                          */
1186                         asoc->overall_error_count = 0;
1187
1188                         /* Generate a SHUTDOWN chunk.  */
1189                         new_obj = sctp_make_shutdown(asoc, chunk);
1190                         if (!new_obj)
1191                                 goto nomem;
1192                         sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1193                                         SCTP_CHUNK(new_obj));
1194                         break;
1195
1196                 case SCTP_CMD_CHUNK_ULP:
1197                         /* Send a chunk to the sockets layer.  */
1198                         SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1199                                           "chunk_up:", cmd->obj.ptr,
1200                                           "ulpq:", &asoc->ulpq);
1201                         sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.ptr,
1202                                             GFP_ATOMIC);
1203                         break;
1204
1205                 case SCTP_CMD_EVENT_ULP:
1206                         /* Send a notification to the sockets layer.  */
1207                         SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1208                                           "event_up:",cmd->obj.ptr,
1209                                           "ulpq:",&asoc->ulpq);
1210                         sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ptr);
1211                         break;
1212
1213                 case SCTP_CMD_REPLY:
1214                         /* If an caller has not already corked, do cork. */
1215                         if (!asoc->outqueue.cork) {
1216                                 sctp_outq_cork(&asoc->outqueue);
1217                                 local_cork = 1;
1218                         }
1219                         /* Send a chunk to our peer.  */
1220                         error = sctp_outq_tail(&asoc->outqueue, cmd->obj.ptr);
1221                         break;
1222
1223                 case SCTP_CMD_SEND_PKT:
1224                         /* Send a full packet to our peer.  */
1225                         packet = cmd->obj.ptr;
1226                         sctp_packet_transmit(packet);
1227                         sctp_ootb_pkt_free(packet);
1228                         break;
1229
1230                 case SCTP_CMD_RETRAN:
1231                         /* Mark a transport for retransmission.  */
1232                         sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1233                                         SCTP_RTXR_T3_RTX);
1234                         break;
1235
1236                 case SCTP_CMD_TRANSMIT:
1237                         /* Kick start transmission. */
1238                         error = sctp_outq_uncork(&asoc->outqueue);
1239                         local_cork = 0;
1240                         break;
1241
1242                 case SCTP_CMD_ECN_CE:
1243                         /* Do delayed CE processing.   */
1244                         sctp_do_ecn_ce_work(asoc, cmd->obj.u32);
1245                         break;
1246
1247                 case SCTP_CMD_ECN_ECNE:
1248                         /* Do delayed ECNE processing. */
1249                         new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32,
1250                                                         chunk);
1251                         if (new_obj)
1252                                 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1253                                                 SCTP_CHUNK(new_obj));
1254                         break;
1255
1256                 case SCTP_CMD_ECN_CWR:
1257                         /* Do delayed CWR processing.  */
1258                         sctp_do_ecn_cwr_work(asoc, cmd->obj.u32);
1259                         break;
1260
1261                 case SCTP_CMD_SETUP_T2:
1262                         sctp_cmd_setup_t2(commands, asoc, cmd->obj.ptr);
1263                         break;
1264
1265                 case SCTP_CMD_TIMER_START:
1266                         timer = &asoc->timers[cmd->obj.to];
1267                         timeout = asoc->timeouts[cmd->obj.to];
1268                         BUG_ON(!timeout);
1269
1270                         timer->expires = jiffies + timeout;
1271                         sctp_association_hold(asoc);
1272                         add_timer(timer);
1273                         break;
1274
1275                 case SCTP_CMD_TIMER_RESTART:
1276                         timer = &asoc->timers[cmd->obj.to];
1277                         timeout = asoc->timeouts[cmd->obj.to];
1278                         if (!mod_timer(timer, jiffies + timeout))
1279                                 sctp_association_hold(asoc);
1280                         break;
1281
1282                 case SCTP_CMD_TIMER_STOP:
1283                         timer = &asoc->timers[cmd->obj.to];
1284                         if (timer_pending(timer) && del_timer(timer))
1285                                 sctp_association_put(asoc);
1286                         break;
1287
1288                 case SCTP_CMD_INIT_CHOOSE_TRANSPORT:
1289                         chunk = cmd->obj.ptr;
1290                         t = sctp_assoc_choose_init_transport(asoc);
1291                         asoc->init_last_sent_to = t;
1292                         chunk->transport = t;
1293                         t->init_sent_count++;
1294                         break;
1295
1296                 case SCTP_CMD_INIT_RESTART:
1297                         /* Do the needed accounting and updates
1298                          * associated with restarting an initialization
1299                          * timer. Only multiply the timeout by two if
1300                          * all transports have been tried at the current
1301                          * timeout.
1302                          */
1303                         t = asoc->init_last_sent_to;
1304                         asoc->init_err_counter++;
1305
1306                         if (t->init_sent_count > (asoc->init_cycle + 1)) {
1307                                 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] *= 2;
1308                                 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] >
1309                                     asoc->max_init_timeo) {
1310                                         asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
1311                                                 asoc->max_init_timeo;
1312                                 }
1313                                 asoc->init_cycle++;
1314                                 SCTP_DEBUG_PRINTK(
1315                                         "T1 INIT Timeout adjustment"
1316                                         " init_err_counter: %d"
1317                                         " cycle: %d"
1318                                         " timeout: %ld\n",
1319                                         asoc->init_err_counter,
1320                                         asoc->init_cycle,
1321                                         asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT]);
1322                         }
1323
1324                         sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
1325                                         SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
1326                         break;
1327
1328                 case SCTP_CMD_COOKIEECHO_RESTART:
1329                         /* Do the needed accounting and updates
1330                          * associated with restarting an initialization
1331                          * timer. Only multiply the timeout by two if
1332                          * all transports have been tried at the current
1333                          * timeout.
1334                          */
1335                         asoc->init_err_counter++;
1336
1337                         asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] *= 2;
1338                         if (asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] >
1339                             asoc->max_init_timeo) {
1340                                 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
1341                                         asoc->max_init_timeo;
1342                         }
1343                         SCTP_DEBUG_PRINTK(
1344                                 "T1 COOKIE Timeout adjustment"
1345                                 " init_err_counter: %d"
1346                                 " timeout: %ld\n",
1347                                 asoc->init_err_counter,
1348                                 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE]);
1349
1350                         /* If we've sent any data bundled with
1351                          * COOKIE-ECHO we need to resend.
1352                          */
1353                         list_for_each(pos, &asoc->peer.transport_addr_list) {
1354                                 t = list_entry(pos, struct sctp_transport,
1355                                                transports);
1356                                 sctp_retransmit_mark(&asoc->outqueue, t, 0);
1357                         }
1358
1359                         sctp_add_cmd_sf(commands,
1360                                         SCTP_CMD_TIMER_RESTART,
1361                                         SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
1362                         break;
1363
1364                 case SCTP_CMD_INIT_FAILED:
1365                         sctp_cmd_init_failed(commands, asoc, cmd->obj.err);
1366                         break;
1367
1368                 case SCTP_CMD_ASSOC_FAILED:
1369                         sctp_cmd_assoc_failed(commands, asoc, event_type,
1370                                               subtype, chunk, cmd->obj.err);
1371                         break;
1372
1373                 case SCTP_CMD_INIT_COUNTER_INC:
1374                         asoc->init_err_counter++;
1375                         break;
1376
1377                 case SCTP_CMD_INIT_COUNTER_RESET:
1378                         asoc->init_err_counter = 0;
1379                         asoc->init_cycle = 0;
1380                         break;
1381
1382                 case SCTP_CMD_REPORT_DUP:
1383                         sctp_tsnmap_mark_dup(&asoc->peer.tsn_map,
1384                                              cmd->obj.u32);
1385                         break;
1386
1387                 case SCTP_CMD_REPORT_BAD_TAG:
1388                         SCTP_DEBUG_PRINTK("vtag mismatch!\n");
1389                         break;
1390
1391                 case SCTP_CMD_STRIKE:
1392                         /* Mark one strike against a transport.  */
1393                         sctp_do_8_2_transport_strike(asoc, cmd->obj.transport);
1394                         break;
1395
1396                 case SCTP_CMD_TRANSPORT_RESET:
1397                         t = cmd->obj.transport;
1398                         sctp_cmd_transport_reset(commands, asoc, t);
1399                         break;
1400
1401                 case SCTP_CMD_TRANSPORT_ON:
1402                         t = cmd->obj.transport;
1403                         sctp_cmd_transport_on(commands, asoc, t, chunk);
1404                         break;
1405
1406                 case SCTP_CMD_HB_TIMERS_START:
1407                         sctp_cmd_hb_timers_start(commands, asoc);
1408                         break;
1409
1410                 case SCTP_CMD_HB_TIMER_UPDATE:
1411                         t = cmd->obj.transport;
1412                         sctp_cmd_hb_timer_update(commands, asoc, t);
1413                         break;
1414
1415                 case SCTP_CMD_HB_TIMERS_STOP:
1416                         sctp_cmd_hb_timers_stop(commands, asoc);
1417                         break;
1418
1419                 case SCTP_CMD_REPORT_ERROR:
1420                         error = cmd->obj.error;
1421                         break;
1422
1423                 case SCTP_CMD_PROCESS_CTSN:
1424                         /* Dummy up a SACK for processing. */
1425                         sackh.cum_tsn_ack = cmd->obj.u32;
1426                         sackh.a_rwnd = 0;
1427                         sackh.num_gap_ack_blocks = 0;
1428                         sackh.num_dup_tsns = 0;
1429                         sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK,
1430                                         SCTP_SACKH(&sackh));
1431                         break;
1432
1433                 case SCTP_CMD_DISCARD_PACKET:
1434                         /* We need to discard the whole packet.  */
1435                         chunk->pdiscard = 1;
1436                         break;
1437
1438                 case SCTP_CMD_RTO_PENDING:
1439                         t = cmd->obj.transport;
1440                         t->rto_pending = 1;
1441                         break;
1442
1443                 case SCTP_CMD_PART_DELIVER:
1444                         sctp_ulpq_partial_delivery(&asoc->ulpq, cmd->obj.ptr,
1445                                                    GFP_ATOMIC);
1446                         break;
1447
1448                 case SCTP_CMD_RENEGE:
1449                         sctp_ulpq_renege(&asoc->ulpq, cmd->obj.ptr,
1450                                          GFP_ATOMIC);
1451                         break;
1452
1453                 case SCTP_CMD_SETUP_T4:
1454                         sctp_cmd_setup_t4(commands, asoc, cmd->obj.ptr);
1455                         break;
1456
1457                 case SCTP_CMD_PROCESS_OPERR:
1458                         sctp_cmd_process_operr(commands, asoc, chunk);
1459                         break;
1460                 case SCTP_CMD_CLEAR_INIT_TAG:
1461                         asoc->peer.i.init_tag = 0;
1462                         break;
1463                 case SCTP_CMD_DEL_NON_PRIMARY:
1464                         sctp_cmd_del_non_primary(asoc);
1465                         break;
1466                 case SCTP_CMD_T3_RTX_TIMERS_STOP:
1467                         sctp_cmd_t3_rtx_timers_stop(commands, asoc);
1468                         break;
1469                 case SCTP_CMD_FORCE_PRIM_RETRAN:
1470                         t = asoc->peer.retran_path;
1471                         asoc->peer.retran_path = asoc->peer.primary_path;
1472                         error = sctp_outq_uncork(&asoc->outqueue);
1473                         local_cork = 0;
1474                         asoc->peer.retran_path = t;
1475                         break;
1476                 case SCTP_CMD_SET_SK_ERR:
1477                         sctp_cmd_set_sk_err(asoc, cmd->obj.error);
1478                         break;
1479                 default:
1480                         printk(KERN_WARNING "Impossible command: %u, %p\n",
1481                                cmd->verb, cmd->obj.ptr);
1482                         break;
1483                 };
1484                 if (error)
1485                         break;
1486         }
1487
1488 out:
1489         if (local_cork)
1490                 sctp_outq_uncork(&asoc->outqueue);
1491         return error;
1492 nomem:
1493         error = -ENOMEM;
1494         goto out;
1495 }
1496