?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
writeback: split writeback_inodes_wb
[linux-2.6/next.git] / net / sctp / sm_sideeffect.c
blobf5e5e27cac5ee5918f815fecf1cebbbc6be3203e
1 /* SCTP kernel 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 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 * This SCTP 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 * This SCTP 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 <linux/gfp.h>
55 #include <net/sock.h>
56 #include <net/sctp/sctp.h>
57 #include <net/sctp/sm.h>
58
59 static int sctp_cmd_interpreter(sctp_event_t event_type,
60 sctp_subtype_t subtype,
61 sctp_state_t state,
62 struct sctp_endpoint *ep,
63 struct sctp_association *asoc,
64 void *event_arg,
65 sctp_disposition_t status,
66 sctp_cmd_seq_t *commands,
67 gfp_t gfp);
68 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
69 sctp_state_t state,
70 struct sctp_endpoint *ep,
71 struct sctp_association *asoc,
72 void *event_arg,
73 sctp_disposition_t status,
74 sctp_cmd_seq_t *commands,
75 gfp_t gfp);
76
77 /********************************************************************
78 * Helper functions
79 ********************************************************************/
80
81 /* A helper function for delayed processing of INET ECN CE bit. */
82 static void sctp_do_ecn_ce_work(struct sctp_association *asoc,
83 __u32 lowest_tsn)
84 {
85 /* Save the TSN away for comparison when we receive CWR */
86
87 asoc->last_ecne_tsn = lowest_tsn;
88 asoc->need_ecne = 1;
89 }
90
91 /* Helper function for delayed processing of SCTP ECNE chunk. */
92 /* RFC 2960 Appendix A
93 *
94 * RFC 2481 details a specific bit for a sender to send in
95 * the header of its next outbound TCP segment to indicate to
96 * its peer that it has reduced its congestion window. This
97 * is termed the CWR bit. For SCTP the same indication is made
98 * by including the CWR chunk. This chunk contains one data
99 * element, i.e. the TSN number that was sent in the ECNE chunk.
100 * This element represents the lowest TSN number in the datagram
101 * that was originally marked with the CE bit.
102 */
103 static struct sctp_chunk *sctp_do_ecn_ecne_work(struct sctp_association *asoc,
104 __u32 lowest_tsn,
105 struct sctp_chunk *chunk)
106 {
107 struct sctp_chunk *repl;
108
109 /* Our previously transmitted packet ran into some congestion
110 * so we should take action by reducing cwnd and ssthresh
111 * and then ACK our peer that we we've done so by
112 * sending a CWR.
113 */
114
115 /* First, try to determine if we want to actually lower
116 * our cwnd variables. Only lower them if the ECNE looks more
117 * recent than the last response.
118 */
119 if (TSN_lt(asoc->last_cwr_tsn, lowest_tsn)) {
120 struct sctp_transport *transport;
121
122 /* Find which transport's congestion variables
123 * need to be adjusted.
124 */
125 transport = sctp_assoc_lookup_tsn(asoc, lowest_tsn);
126
127 /* Update the congestion variables. */
128 if (transport)
129 sctp_transport_lower_cwnd(transport,
130 SCTP_LOWER_CWND_ECNE);
131 asoc->last_cwr_tsn = lowest_tsn;
132 }
133
134 /* Always try to quiet the other end. In case of lost CWR,
135 * resend last_cwr_tsn.
136 */
137 repl = sctp_make_cwr(asoc, asoc->last_cwr_tsn, chunk);
138
139 /* If we run out of memory, it will look like a lost CWR. We'll
140 * get back in sync eventually.
141 */
142 return repl;
143 }
144
145 /* Helper function to do delayed processing of ECN CWR chunk. */
146 static void sctp_do_ecn_cwr_work(struct sctp_association *asoc,
147 __u32 lowest_tsn)
148 {
149 /* Turn off ECNE getting auto-prepended to every outgoing
150 * packet
151 */
152 asoc->need_ecne = 0;
153 }
154
155 /* Generate SACK if necessary. We call this at the end of a packet. */
156 static int sctp_gen_sack(struct sctp_association *asoc, int force,
157 sctp_cmd_seq_t *commands)
158 {
159 __u32 ctsn, max_tsn_seen;
160 struct sctp_chunk *sack;
161 struct sctp_transport *trans = asoc->peer.last_data_from;
162 int error = 0;
163
164 if (force ||
165 (!trans && (asoc->param_flags & SPP_SACKDELAY_DISABLE)) ||
166 (trans && (trans->param_flags & SPP_SACKDELAY_DISABLE)))
167 asoc->peer.sack_needed = 1;
168
169 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
170 max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
171
172 /* From 12.2 Parameters necessary per association (i.e. the TCB):
173 *
174 * Ack State : This flag indicates if the next received packet
175 * : is to be responded to with a SACK. ...
176 * : When DATA chunks are out of order, SACK's
177 * : are not delayed (see Section 6).
178 *
179 * [This is actually not mentioned in Section 6, but we
180 * implement it here anyway. --piggy]
181 */
182 if (max_tsn_seen != ctsn)
183 asoc->peer.sack_needed = 1;
184
185 /* From 6.2 Acknowledgement on Reception of DATA Chunks:
186 *
187 * Section 4.2 of [RFC2581] SHOULD be followed. Specifically,
188 * an acknowledgement SHOULD be generated for at least every
189 * second packet (not every second DATA chunk) received, and
190 * SHOULD be generated within 200 ms of the arrival of any
191 * unacknowledged DATA chunk. ...
192 */
193 if (!asoc->peer.sack_needed) {
194 asoc->peer.sack_cnt++;
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 /* We will need a SACK for the next packet. */
203 if (asoc->peer.sack_cnt >= trans->sackfreq - 1)
204 asoc->peer.sack_needed = 1;
205
206 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
207 trans->sackdelay;
208 } else {
209 /* We will need a SACK for the next packet. */
210 if (asoc->peer.sack_cnt >= asoc->sackfreq - 1)
211 asoc->peer.sack_needed = 1;
212
213 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
214 asoc->sackdelay;
215 }
216
217 /* Restart the SACK timer. */
218 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
219 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
220 } else {
221 asoc->a_rwnd = asoc->rwnd;
222 sack = sctp_make_sack(asoc);
223 if (!sack)
224 goto nomem;
225
226 asoc->peer.sack_needed = 0;
227 asoc->peer.sack_cnt = 0;
228
229 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(sack));
230
231 /* Stop the SACK timer. */
232 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
233 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
234 }
235
236 return error;
237 nomem:
238 error = -ENOMEM;
239 return error;
240 }
241
242 /* When the T3-RTX timer expires, it calls this function to create the
243 * relevant state machine event.
244 */
245 void sctp_generate_t3_rtx_event(unsigned long peer)
246 {
247 int error;
248 struct sctp_transport *transport = (struct sctp_transport *) peer;
249 struct sctp_association *asoc = transport->asoc;
250
251 /* Check whether a task is in the sock. */
252
253 sctp_bh_lock_sock(asoc->base.sk);
254 if (sock_owned_by_user(asoc->base.sk)) {
255 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
256
257 /* Try again later. */
258 if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20)))
259 sctp_transport_hold(transport);
260 goto out_unlock;
261 }
262
263 /* Is this transport really dead and just waiting around for
264 * the timer to let go of the reference?
265 */
266 if (transport->dead)
267 goto out_unlock;
268
269 /* Run through the state machine. */
270 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
271 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX),
272 asoc->state,
273 asoc->ep, asoc,
274 transport, GFP_ATOMIC);
275
276 if (error)
277 asoc->base.sk->sk_err = -error;
278
279 out_unlock:
280 sctp_bh_unlock_sock(asoc->base.sk);
281 sctp_transport_put(transport);
282 }
283
284 /* This is a sa interface for producing timeout events. It works
285 * for timeouts which use the association as their parameter.
286 */
287 static void sctp_generate_timeout_event(struct sctp_association *asoc,
288 sctp_event_timeout_t timeout_type)
289 {
290 int error = 0;
291
292 sctp_bh_lock_sock(asoc->base.sk);
293 if (sock_owned_by_user(asoc->base.sk)) {
294 SCTP_DEBUG_PRINTK("%s:Sock is busy: timer %d\n",
295 __func__,
296 timeout_type);
297
298 /* Try again later. */
299 if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20)))
300 sctp_association_hold(asoc);
301 goto out_unlock;
302 }
303
304 /* Is this association really dead and just waiting around for
305 * the timer to let go of the reference?
306 */
307 if (asoc->base.dead)
308 goto out_unlock;
309
310 /* Run through the state machine. */
311 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
312 SCTP_ST_TIMEOUT(timeout_type),
313 asoc->state, asoc->ep, asoc,
314 (void *)timeout_type, GFP_ATOMIC);
315
316 if (error)
317 asoc->base.sk->sk_err = -error;
318
319 out_unlock:
320 sctp_bh_unlock_sock(asoc->base.sk);
321 sctp_association_put(asoc);
322 }
323
324 static void sctp_generate_t1_cookie_event(unsigned long data)
325 {
326 struct sctp_association *asoc = (struct sctp_association *) data;
327 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE);
328 }
329
330 static void sctp_generate_t1_init_event(unsigned long data)
331 {
332 struct sctp_association *asoc = (struct sctp_association *) data;
333 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT);
334 }
335
336 static void sctp_generate_t2_shutdown_event(unsigned long data)
337 {
338 struct sctp_association *asoc = (struct sctp_association *) data;
339 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN);
340 }
341
342 static void sctp_generate_t4_rto_event(unsigned long data)
343 {
344 struct sctp_association *asoc = (struct sctp_association *) data;
345 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO);
346 }
347
348 static void sctp_generate_t5_shutdown_guard_event(unsigned long data)
349 {
350 struct sctp_association *asoc = (struct sctp_association *)data;
351 sctp_generate_timeout_event(asoc,
352 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD);
353
354 } /* sctp_generate_t5_shutdown_guard_event() */
355
356 static void sctp_generate_autoclose_event(unsigned long data)
357 {
358 struct sctp_association *asoc = (struct sctp_association *) data;
359 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE);
360 }
361
362 /* Generate a heart beat event. If the sock is busy, reschedule. Make
363 * sure that the transport is still valid.
364 */
365 void sctp_generate_heartbeat_event(unsigned long data)
366 {
367 int error = 0;
368 struct sctp_transport *transport = (struct sctp_transport *) data;
369 struct sctp_association *asoc = transport->asoc;
370
371 sctp_bh_lock_sock(asoc->base.sk);
372 if (sock_owned_by_user(asoc->base.sk)) {
373 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
374
375 /* Try again later. */
376 if (!mod_timer(&transport->hb_timer, jiffies + (HZ/20)))
377 sctp_transport_hold(transport);
378 goto out_unlock;
379 }
380
381 /* Is this structure just waiting around for us to actually
382 * get destroyed?
383 */
384 if (transport->dead)
385 goto out_unlock;
386
387 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
388 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT),
389 asoc->state, asoc->ep, asoc,
390 transport, GFP_ATOMIC);
391
392 if (error)
393 asoc->base.sk->sk_err = -error;
394
395 out_unlock:
396 sctp_bh_unlock_sock(asoc->base.sk);
397 sctp_transport_put(transport);
398 }
399
400 /* Handle the timeout of the ICMP protocol unreachable timer. Trigger
401 * the correct state machine transition that will close the association.
402 */
403 void sctp_generate_proto_unreach_event(unsigned long data)
404 {
405 struct sctp_transport *transport = (struct sctp_transport *) data;
406 struct sctp_association *asoc = transport->asoc;
407
408 sctp_bh_lock_sock(asoc->base.sk);
409 if (sock_owned_by_user(asoc->base.sk)) {
410 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
411
412 /* Try again later. */
413 if (!mod_timer(&transport->proto_unreach_timer,
414 jiffies + (HZ/20)))
415 sctp_association_hold(asoc);
416 goto out_unlock;
417 }
418
419 /* Is this structure just waiting around for us to actually
420 * get destroyed?
421 */
422 if (asoc->base.dead)
423 goto out_unlock;
424
425 sctp_do_sm(SCTP_EVENT_T_OTHER,
426 SCTP_ST_OTHER(SCTP_EVENT_ICMP_PROTO_UNREACH),
427 asoc->state, asoc->ep, asoc, transport, GFP_ATOMIC);
428
429 out_unlock:
430 sctp_bh_unlock_sock(asoc->base.sk);
431 sctp_association_put(asoc);
432 }
433
434
435 /* Inject a SACK Timeout event into the state machine. */
436 static void sctp_generate_sack_event(unsigned long data)
437 {
438 struct sctp_association *asoc = (struct sctp_association *) data;
439 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK);
440 }
441
442 sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = {
443 NULL,
444 sctp_generate_t1_cookie_event,
445 sctp_generate_t1_init_event,
446 sctp_generate_t2_shutdown_event,
447 NULL,
448 sctp_generate_t4_rto_event,
449 sctp_generate_t5_shutdown_guard_event,
450 NULL,
451 sctp_generate_sack_event,
452 sctp_generate_autoclose_event,
453 };
454
455
456 /* RFC 2960 8.2 Path Failure Detection
457 *
458 * When its peer endpoint is multi-homed, an endpoint should keep a
459 * error counter for each of the destination transport addresses of the
460 * peer endpoint.
461 *
462 * Each time the T3-rtx timer expires on any address, or when a
463 * HEARTBEAT sent to an idle address is not acknowledged within a RTO,
464 * the error counter of that destination address will be incremented.
465 * When the value in the error counter exceeds the protocol parameter
466 * 'Path.Max.Retrans' of that destination address, the endpoint should
467 * mark the destination transport address as inactive, and a
468 * notification SHOULD be sent to the upper layer.
469 *
470 */
471 static void sctp_do_8_2_transport_strike(struct sctp_association *asoc,
472 struct sctp_transport *transport,
473 int is_hb)
474 {
475 /* The check for association's overall error counter exceeding the
476 * threshold is done in the state function.
477 */
478 /* We are here due to a timer expiration. If the timer was
479 * not a HEARTBEAT, then normal error tracking is done.
480 * If the timer was a heartbeat, we only increment error counts
481 * when we already have an outstanding HEARTBEAT that has not
482 * been acknowledged.
483 * Additionaly, some tranport states inhibit error increments.
484 */
485 if (!is_hb) {
486 asoc->overall_error_count++;
487 if (transport->state != SCTP_INACTIVE)
488 transport->error_count++;
489 } else if (transport->hb_sent) {
490 if (transport->state != SCTP_UNCONFIRMED)
491 asoc->overall_error_count++;
492 if (transport->state != SCTP_INACTIVE)
493 transport->error_count++;
494 }
495
496 if (transport->state != SCTP_INACTIVE &&
497 (transport->error_count > transport->pathmaxrxt)) {
498 SCTP_DEBUG_PRINTK_IPADDR("transport_strike:association %p",
499 " transport IP: port:%d failed.\n",
500 asoc,
501 (&transport->ipaddr),
502 ntohs(transport->ipaddr.v4.sin_port));
503 sctp_assoc_control_transport(asoc, transport,
504 SCTP_TRANSPORT_DOWN,
505 SCTP_FAILED_THRESHOLD);
506 }
507
508 /* E2) For the destination address for which the timer
509 * expires, set RTO <- RTO * 2 ("back off the timer"). The
510 * maximum value discussed in rule C7 above (RTO.max) may be
511 * used to provide an upper bound to this doubling operation.
512 *
513 * Special Case: the first HB doesn't trigger exponential backoff.
514 * The first unacknowledged HB triggers it. We do this with a flag
515 * that indicates that we have an outstanding HB.
516 */
517 if (!is_hb || transport->hb_sent) {
518 transport->rto = min((transport->rto * 2), transport->asoc->rto_max);
519 }
520 }
521
522 /* Worker routine to handle INIT command failure. */
523 static void sctp_cmd_init_failed(sctp_cmd_seq_t *commands,
524 struct sctp_association *asoc,
525 unsigned error)
526 {
527 struct sctp_ulpevent *event;
528
529 event = sctp_ulpevent_make_assoc_change(asoc,0, SCTP_CANT_STR_ASSOC,
530 (__u16)error, 0, 0, NULL,
531 GFP_ATOMIC);
532
533 if (event)
534 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
535 SCTP_ULPEVENT(event));
536
537 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
538 SCTP_STATE(SCTP_STATE_CLOSED));
539
540 /* SEND_FAILED sent later when cleaning up the association. */
541 asoc->outqueue.error = error;
542 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
543 }
544
545 /* Worker routine to handle SCTP_CMD_ASSOC_FAILED. */
546 static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands,
547 struct sctp_association *asoc,
548 sctp_event_t event_type,
549 sctp_subtype_t subtype,
550 struct sctp_chunk *chunk,
551 unsigned error)
552 {
553 struct sctp_ulpevent *event;
554
555 /* Cancel any partial delivery in progress. */
556 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
557
558 if (event_type == SCTP_EVENT_T_CHUNK && subtype.chunk == SCTP_CID_ABORT)
559 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
560 (__u16)error, 0, 0, chunk,
561 GFP_ATOMIC);
562 else
563 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
564 (__u16)error, 0, 0, NULL,
565 GFP_ATOMIC);
566 if (event)
567 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
568 SCTP_ULPEVENT(event));
569
570 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
571 SCTP_STATE(SCTP_STATE_CLOSED));
572
573 /* SEND_FAILED sent later when cleaning up the association. */
574 asoc->outqueue.error = error;
575 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
576 }
577
578 /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT
579 * inside the cookie. In reality, this is only used for INIT-ACK processing
580 * since all other cases use "temporary" associations and can do all
581 * their work in statefuns directly.
582 */
583 static int sctp_cmd_process_init(sctp_cmd_seq_t *commands,
584 struct sctp_association *asoc,
585 struct sctp_chunk *chunk,
586 sctp_init_chunk_t *peer_init,
587 gfp_t gfp)
588 {
589 int error;
590
591 /* We only process the init as a sideeffect in a single
592 * case. This is when we process the INIT-ACK. If we
593 * fail during INIT processing (due to malloc problems),
594 * just return the error and stop processing the stack.
595 */
596 if (!sctp_process_init(asoc, chunk->chunk_hdr->type,
597 sctp_source(chunk), peer_init, gfp))
598 error = -ENOMEM;
599 else
600 error = 0;
601
602 return error;
603 }
604
605 /* Helper function to break out starting up of heartbeat timers. */
606 static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds,
607 struct sctp_association *asoc)
608 {
609 struct sctp_transport *t;
610
611 /* Start a heartbeat timer for each transport on the association.
612 * hold a reference on the transport to make sure none of
613 * the needed data structures go away.
614 */
615 list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) {
616
617 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
618 sctp_transport_hold(t);
619 }
620 }
621
622 static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds,
623 struct sctp_association *asoc)
624 {
625 struct sctp_transport *t;
626
627 /* Stop all heartbeat timers. */
628
629 list_for_each_entry(t, &asoc->peer.transport_addr_list,
630 transports) {
631 if (del_timer(&t->hb_timer))
632 sctp_transport_put(t);
633 }
634 }
635
636 /* Helper function to stop any pending T3-RTX timers */
637 static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds,
638 struct sctp_association *asoc)
639 {
640 struct sctp_transport *t;
641
642 list_for_each_entry(t, &asoc->peer.transport_addr_list,
643 transports) {
644 if (timer_pending(&t->T3_rtx_timer) &&
645 del_timer(&t->T3_rtx_timer)) {
646 sctp_transport_put(t);
647 }
648 }
649 }
650
651
652 /* Helper function to update the heartbeat timer. */
653 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds,
654 struct sctp_transport *t)
655 {
656 /* Update the heartbeat timer. */
657 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
658 sctp_transport_hold(t);
659 }
660
661 /* Helper function to handle the reception of an HEARTBEAT ACK. */
662 static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds,
663 struct sctp_association *asoc,
664 struct sctp_transport *t,
665 struct sctp_chunk *chunk)
666 {
667 sctp_sender_hb_info_t *hbinfo;
668
669 /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the
670 * HEARTBEAT should clear the error counter of the destination
671 * transport address to which the HEARTBEAT was sent.
672 * The association's overall error count is also cleared.
673 */
674 t->error_count = 0;
675 t->asoc->overall_error_count = 0;
676
677 /* Clear the hb_sent flag to signal that we had a good
678 * acknowledgement.
679 */
680 t->hb_sent = 0;
681
682 /* Mark the destination transport address as active if it is not so
683 * marked.
684 */
685 if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED))
686 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
687 SCTP_HEARTBEAT_SUCCESS);
688
689 /* The receiver of the HEARTBEAT ACK should also perform an
690 * RTT measurement for that destination transport address
691 * using the time value carried in the HEARTBEAT ACK chunk.
692 * If the transport's rto_pending variable has been cleared,
693 * it was most likely due to a retransmit. However, we want
694 * to re-enable it to properly update the rto.
695 */
696 if (t->rto_pending == 0)
697 t->rto_pending = 1;
698
699 hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data;
700 sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at));
701
702 /* Update the heartbeat timer. */
703 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
704 sctp_transport_hold(t);
705 }
706
707
708 /* Helper function to process the process SACK command. */
709 static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds,
710 struct sctp_association *asoc,
711 struct sctp_sackhdr *sackh)
712 {
713 int err = 0;
714
715 if (sctp_outq_sack(&asoc->outqueue, sackh)) {
716 /* There are no more TSNs awaiting SACK. */
717 err = sctp_do_sm(SCTP_EVENT_T_OTHER,
718 SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN),
719 asoc->state, asoc->ep, asoc, NULL,
720 GFP_ATOMIC);
721 }
722
723 return err;
724 }
725
726 /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set
727 * the transport for a shutdown chunk.
728 */
729 static void sctp_cmd_setup_t2(sctp_cmd_seq_t *cmds,
730 struct sctp_association *asoc,
731 struct sctp_chunk *chunk)
732 {
733 struct sctp_transport *t;
734
735 if (chunk->transport)
736 t = chunk->transport;
737 else {
738 t = sctp_assoc_choose_alter_transport(asoc,
739 asoc->shutdown_last_sent_to);
740 chunk->transport = t;
741 }
742 asoc->shutdown_last_sent_to = t;
743 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto;
744 }
745
746 /* Helper function to change the state of an association. */
747 static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds,
748 struct sctp_association *asoc,
749 sctp_state_t state)
750 {
751 struct sock *sk = asoc->base.sk;
752
753 asoc->state = state;
754
755 SCTP_DEBUG_PRINTK("sctp_cmd_new_state: asoc %p[%s]\n",
756 asoc, sctp_state_tbl[state]);
757
758 if (sctp_style(sk, TCP)) {
759 /* Change the sk->sk_state of a TCP-style socket that has
760 * successfully completed a connect() call.
761 */
762 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED))
763 sk->sk_state = SCTP_SS_ESTABLISHED;
764
765 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */
766 if (sctp_state(asoc, SHUTDOWN_RECEIVED) &&
767 sctp_sstate(sk, ESTABLISHED))
768 sk->sk_shutdown |= RCV_SHUTDOWN;
769 }
770
771 if (sctp_state(asoc, COOKIE_WAIT)) {
772 /* Reset init timeouts since they may have been
773 * increased due to timer expirations.
774 */
775 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
776 asoc->rto_initial;
777 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
778 asoc->rto_initial;
779 }
780
781 if (sctp_state(asoc, ESTABLISHED) ||
782 sctp_state(asoc, CLOSED) ||
783 sctp_state(asoc, SHUTDOWN_RECEIVED)) {
784 /* Wake up any processes waiting in the asoc's wait queue in
785 * sctp_wait_for_connect() or sctp_wait_for_sndbuf().
786 */
787 if (waitqueue_active(&asoc->wait))
788 wake_up_interruptible(&asoc->wait);
789
790 /* Wake up any processes waiting in the sk's sleep queue of
791 * a TCP-style or UDP-style peeled-off socket in
792 * sctp_wait_for_accept() or sctp_wait_for_packet().
793 * For a UDP-style socket, the waiters are woken up by the
794 * notifications.
795 */
796 if (!sctp_style(sk, UDP))
797 sk->sk_state_change(sk);
798 }
799 }
800
801 /* Helper function to delete an association. */
802 static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds,
803 struct sctp_association *asoc)
804 {
805 struct sock *sk = asoc->base.sk;
806
807 /* If it is a non-temporary association belonging to a TCP-style
808 * listening socket that is not closed, do not free it so that accept()
809 * can pick it up later.
810 */
811 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) &&
812 (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK))
813 return;
814
815 sctp_unhash_established(asoc);
816 sctp_association_free(asoc);
817 }
818
819 /*
820 * ADDIP Section 4.1 ASCONF Chunk Procedures
821 * A4) Start a T-4 RTO timer, using the RTO value of the selected
822 * destination address (we use active path instead of primary path just
823 * because primary path may be inactive.
824 */
825 static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds,
826 struct sctp_association *asoc,
827 struct sctp_chunk *chunk)
828 {
829 struct sctp_transport *t;
830
831 t = sctp_assoc_choose_alter_transport(asoc, chunk->transport);
832 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto;
833 chunk->transport = t;
834 }
835
836 /* Process an incoming Operation Error Chunk. */
837 static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds,
838 struct sctp_association *asoc,
839 struct sctp_chunk *chunk)
840 {
841 struct sctp_errhdr *err_hdr;
842 struct sctp_ulpevent *ev;
843
844 while (chunk->chunk_end > chunk->skb->data) {
845 err_hdr = (struct sctp_errhdr *)(chunk->skb->data);
846
847 ev = sctp_ulpevent_make_remote_error(asoc, chunk, 0,
848 GFP_ATOMIC);
849 if (!ev)
850 return;
851
852 sctp_ulpq_tail_event(&asoc->ulpq, ev);
853
854 switch (err_hdr->cause) {
855 case SCTP_ERROR_UNKNOWN_CHUNK:
856 {
857 sctp_chunkhdr_t *unk_chunk_hdr;
858
859 unk_chunk_hdr = (sctp_chunkhdr_t *)err_hdr->variable;
860 switch (unk_chunk_hdr->type) {
861 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with
862 * an ERROR chunk reporting that it did not recognized
863 * the ASCONF chunk type, the sender of the ASCONF MUST
864 * NOT send any further ASCONF chunks and MUST stop its
865 * T-4 timer.
866 */
867 case SCTP_CID_ASCONF:
868 if (asoc->peer.asconf_capable == 0)
869 break;
870
871 asoc->peer.asconf_capable = 0;
872 sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP,
873 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
874 break;
875 default:
876 break;
877 }
878 break;
879 }
880 default:
881 break;
882 }
883 }
884 }
885
886 /* Process variable FWDTSN chunk information. */
887 static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq,
888 struct sctp_chunk *chunk)
889 {
890 struct sctp_fwdtsn_skip *skip;
891 /* Walk through all the skipped SSNs */
892 sctp_walk_fwdtsn(skip, chunk) {
893 sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn));
894 }
895 }
896
897 /* Helper function to remove the association non-primary peer
898 * transports.
899 */
900 static void sctp_cmd_del_non_primary(struct sctp_association *asoc)
901 {
902 struct sctp_transport *t;
903 struct list_head *pos;
904 struct list_head *temp;
905
906 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
907 t = list_entry(pos, struct sctp_transport, transports);
908 if (!sctp_cmp_addr_exact(&t->ipaddr,
909 &asoc->peer.primary_addr)) {
910 sctp_assoc_del_peer(asoc, &t->ipaddr);
911 }
912 }
913 }
914
915 /* Helper function to set sk_err on a 1-1 style socket. */
916 static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error)
917 {
918 struct sock *sk = asoc->base.sk;
919
920 if (!sctp_style(sk, UDP))
921 sk->sk_err = error;
922 }
923
924 /* Helper function to generate an association change event */
925 static void sctp_cmd_assoc_change(sctp_cmd_seq_t *commands,
926 struct sctp_association *asoc,
927 u8 state)
928 {
929 struct sctp_ulpevent *ev;
930
931 ev = sctp_ulpevent_make_assoc_change(asoc, 0, state, 0,
932 asoc->c.sinit_num_ostreams,
933 asoc->c.sinit_max_instreams,
934 NULL, GFP_ATOMIC);
935 if (ev)
936 sctp_ulpq_tail_event(&asoc->ulpq, ev);
937 }
938
939 /* Helper function to generate an adaptation indication event */
940 static void sctp_cmd_adaptation_ind(sctp_cmd_seq_t *commands,
941 struct sctp_association *asoc)
942 {
943 struct sctp_ulpevent *ev;
944
945 ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC);
946
947 if (ev)
948 sctp_ulpq_tail_event(&asoc->ulpq, ev);
949 }
950
951
952 static void sctp_cmd_t1_timer_update(struct sctp_association *asoc,
953 sctp_event_timeout_t timer,
954 char *name)
955 {
956 struct sctp_transport *t;
957
958 t = asoc->init_last_sent_to;
959 asoc->init_err_counter++;
960
961 if (t->init_sent_count > (asoc->init_cycle + 1)) {
962 asoc->timeouts[timer] *= 2;
963 if (asoc->timeouts[timer] > asoc->max_init_timeo) {
964 asoc->timeouts[timer] = asoc->max_init_timeo;
965 }
966 asoc->init_cycle++;
967 SCTP_DEBUG_PRINTK(
968 "T1 %s Timeout adjustment"
969 " init_err_counter: %d"
970 " cycle: %d"
971 " timeout: %ld\n",
972 name,
973 asoc->init_err_counter,
974 asoc->init_cycle,
975 asoc->timeouts[timer]);
976 }
977
978 }
979
980 /* Send the whole message, chunk by chunk, to the outqueue.
981 * This way the whole message is queued up and bundling if
982 * encouraged for small fragments.
983 */
984 static int sctp_cmd_send_msg(struct sctp_association *asoc,
985 struct sctp_datamsg *msg)
986 {
987 struct sctp_chunk *chunk;
988 int error = 0;
989
990 list_for_each_entry(chunk, &msg->chunks, frag_list) {
991 error = sctp_outq_tail(&asoc->outqueue, chunk);
992 if (error)
993 break;
994 }
995
996 return error;
997 }
998
999
1000 /* Sent the next ASCONF packet currently stored in the association.
1001 * This happens after the ASCONF_ACK was succeffully processed.
1002 */
1003 static void sctp_cmd_send_asconf(struct sctp_association *asoc)
1004 {
1005 /* Send the next asconf chunk from the addip chunk
1006 * queue.
1007 */
1008 if (!list_empty(&asoc->addip_chunk_list)) {
1009 struct list_head *entry = asoc->addip_chunk_list.next;
1010 struct sctp_chunk *asconf = list_entry(entry,
1011 struct sctp_chunk, list);
1012 list_del_init(entry);
1013
1014 /* Hold the chunk until an ASCONF_ACK is received. */
1015 sctp_chunk_hold(asconf);
1016 if (sctp_primitive_ASCONF(asoc, asconf))
1017 sctp_chunk_free(asconf);
1018 else
1019 asoc->addip_last_asconf = asconf;
1020 }
1021 }
1022
1023
1024 /* These three macros allow us to pull the debugging code out of the
1025 * main flow of sctp_do_sm() to keep attention focused on the real
1026 * functionality there.
1027 */
1028 #define DEBUG_PRE \
1029 SCTP_DEBUG_PRINTK("sctp_do_sm prefn: " \
1030 "ep %p, %s, %s, asoc %p[%s], %s\n", \
1031 ep, sctp_evttype_tbl[event_type], \
1032 (*debug_fn)(subtype), asoc, \
1033 sctp_state_tbl[state], state_fn->name)
1034
1035 #define DEBUG_POST \
1036 SCTP_DEBUG_PRINTK("sctp_do_sm postfn: " \
1037 "asoc %p, status: %s\n", \
1038 asoc, sctp_status_tbl[status])
1039
1040 #define DEBUG_POST_SFX \
1041 SCTP_DEBUG_PRINTK("sctp_do_sm post sfx: error %d, asoc %p[%s]\n", \
1042 error, asoc, \
1043 sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \
1044 sctp_assoc2id(asoc)))?asoc->state:SCTP_STATE_CLOSED])
1045
1046 /*
1047 * This is the master state machine processing function.
1048 *
1049 * If you want to understand all of lksctp, this is a
1050 * good place to start.
1051 */
1052 int sctp_do_sm(sctp_event_t event_type, sctp_subtype_t subtype,
1053 sctp_state_t state,
1054 struct sctp_endpoint *ep,
1055 struct sctp_association *asoc,
1056 void *event_arg,
1057 gfp_t gfp)
1058 {
1059 sctp_cmd_seq_t commands;
1060 const sctp_sm_table_entry_t *state_fn;
1061 sctp_disposition_t status;
1062 int error = 0;
1063 typedef const char *(printfn_t)(sctp_subtype_t);
1064
1065 static printfn_t *table[] = {
1066 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname,
1067 };
1068 printfn_t *debug_fn __attribute__ ((unused)) = table[event_type];
1069
1070 /* Look up the state function, run it, and then process the
1071 * side effects. These three steps are the heart of lksctp.
1072 */
1073 state_fn = sctp_sm_lookup_event(event_type, state, subtype);
1074
1075 sctp_init_cmd_seq(&commands);
1076
1077 DEBUG_PRE;
1078 status = (*state_fn->fn)(ep, asoc, subtype, event_arg, &commands);
1079 DEBUG_POST;
1080
1081 error = sctp_side_effects(event_type, subtype, state,
1082 ep, asoc, event_arg, status,
1083 &commands, gfp);
1084 DEBUG_POST_SFX;
1085
1086 return error;
1087 }
1088
1089 #undef DEBUG_PRE
1090 #undef DEBUG_POST
1091
1092 /*****************************************************************
1093 * This the master state function side effect processing function.
1094 *****************************************************************/
1095 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
1096 sctp_state_t state,
1097 struct sctp_endpoint *ep,
1098 struct sctp_association *asoc,
1099 void *event_arg,
1100 sctp_disposition_t status,
1101 sctp_cmd_seq_t *commands,
1102 gfp_t gfp)
1103 {
1104 int error;
1105
1106 /* FIXME - Most of the dispositions left today would be categorized
1107 * as "exceptional" dispositions. For those dispositions, it
1108 * may not be proper to run through any of the commands at all.
1109 * For example, the command interpreter might be run only with
1110 * disposition SCTP_DISPOSITION_CONSUME.
1111 */
1112 if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state,
1113 ep, asoc,
1114 event_arg, status,
1115 commands, gfp)))
1116 goto bail;
1117
1118 switch (status) {
1119 case SCTP_DISPOSITION_DISCARD:
1120 SCTP_DEBUG_PRINTK("Ignored sctp protocol event - state %d, "
1121 "event_type %d, event_id %d\n",
1122 state, event_type, subtype.chunk);
1123 break;
1124
1125 case SCTP_DISPOSITION_NOMEM:
1126 /* We ran out of memory, so we need to discard this
1127 * packet.
1128 */
1129 /* BUG--we should now recover some memory, probably by
1130 * reneging...
1131 */
1132 error = -ENOMEM;
1133 break;
1134
1135 case SCTP_DISPOSITION_DELETE_TCB:
1136 /* This should now be a command. */
1137 break;
1138
1139 case SCTP_DISPOSITION_CONSUME:
1140 case SCTP_DISPOSITION_ABORT:
1141 /*
1142 * We should no longer have much work to do here as the
1143 * real work has been done as explicit commands above.
1144 */
1145 break;
1146
1147 case SCTP_DISPOSITION_VIOLATION:
1148 if (net_ratelimit())
1149 printk(KERN_ERR "sctp protocol violation state %d "
1150 "chunkid %d\n", state, subtype.chunk);
1151 break;
1152
1153 case SCTP_DISPOSITION_NOT_IMPL:
1154 printk(KERN_WARNING "sctp unimplemented feature in state %d, "
1155 "event_type %d, event_id %d\n",
1156 state, event_type, subtype.chunk);
1157 break;
1158
1159 case SCTP_DISPOSITION_BUG:
1160 printk(KERN_ERR "sctp bug in state %d, "
1161 "event_type %d, event_id %d\n",
1162 state, event_type, subtype.chunk);
1163 BUG();
1164 break;
1165
1166 default:
1167 printk(KERN_ERR "sctp impossible disposition %d "
1168 "in state %d, event_type %d, event_id %d\n",
1169 status, state, event_type, subtype.chunk);
1170 BUG();
1171 break;
1172 }
1173
1174 bail:
1175 return error;
1176 }
1177
1178 /********************************************************************
1179 * 2nd Level Abstractions
1180 ********************************************************************/
1181
1182 /* This is the side-effect interpreter. */
1183 static int sctp_cmd_interpreter(sctp_event_t event_type,
1184 sctp_subtype_t subtype,
1185 sctp_state_t state,
1186 struct sctp_endpoint *ep,
1187 struct sctp_association *asoc,
1188 void *event_arg,
1189 sctp_disposition_t status,
1190 sctp_cmd_seq_t *commands,
1191 gfp_t gfp)
1192 {
1193 int error = 0;
1194 int force;
1195 sctp_cmd_t *cmd;
1196 struct sctp_chunk *new_obj;
1197 struct sctp_chunk *chunk = NULL;
1198 struct sctp_packet *packet;
1199 struct timer_list *timer;
1200 unsigned long timeout;
1201 struct sctp_transport *t;
1202 struct sctp_sackhdr sackh;
1203 int local_cork = 0;
1204
1205 if (SCTP_EVENT_T_TIMEOUT != event_type)
1206 chunk = (struct sctp_chunk *) event_arg;
1207
1208 /* Note: This whole file is a huge candidate for rework.
1209 * For example, each command could either have its own handler, so
1210 * the loop would look like:
1211 * while (cmds)
1212 * cmd->handle(x, y, z)
1213 * --jgrimm
1214 */
1215 while (NULL != (cmd = sctp_next_cmd(commands))) {
1216 switch (cmd->verb) {
1217 case SCTP_CMD_NOP:
1218 /* Do nothing. */
1219 break;
1220
1221 case SCTP_CMD_NEW_ASOC:
1222 /* Register a new association. */
1223 if (local_cork) {
1224 sctp_outq_uncork(&asoc->outqueue);
1225 local_cork = 0;
1226 }
1227 asoc = cmd->obj.ptr;
1228 /* Register with the endpoint. */
1229 sctp_endpoint_add_asoc(ep, asoc);
1230 sctp_hash_established(asoc);
1231 break;
1232
1233 case SCTP_CMD_UPDATE_ASSOC:
1234 sctp_assoc_update(asoc, cmd->obj.ptr);
1235 break;
1236
1237 case SCTP_CMD_PURGE_OUTQUEUE:
1238 sctp_outq_teardown(&asoc->outqueue);
1239 break;
1240
1241 case SCTP_CMD_DELETE_TCB:
1242 if (local_cork) {
1243 sctp_outq_uncork(&asoc->outqueue);
1244 local_cork = 0;
1245 }
1246 /* Delete the current association. */
1247 sctp_cmd_delete_tcb(commands, asoc);
1248 asoc = NULL;
1249 break;
1250
1251 case SCTP_CMD_NEW_STATE:
1252 /* Enter a new state. */
1253 sctp_cmd_new_state(commands, asoc, cmd->obj.state);
1254 break;
1255
1256 case SCTP_CMD_REPORT_TSN:
1257 /* Record the arrival of a TSN. */
1258 error = sctp_tsnmap_mark(&asoc->peer.tsn_map,
1259 cmd->obj.u32);
1260 break;
1261
1262 case SCTP_CMD_REPORT_FWDTSN:
1263 /* Move the Cumulattive TSN Ack ahead. */
1264 sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32);
1265
1266 /* purge the fragmentation queue */
1267 sctp_ulpq_reasm_flushtsn(&asoc->ulpq, cmd->obj.u32);
1268
1269 /* Abort any in progress partial delivery. */
1270 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
1271 break;
1272
1273 case SCTP_CMD_PROCESS_FWDTSN:
1274 sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.ptr);
1275 break;
1276
1277 case SCTP_CMD_GEN_SACK:
1278 /* Generate a Selective ACK.
1279 * The argument tells us whether to just count
1280 * the packet and MAYBE generate a SACK, or
1281 * force a SACK out.
1282 */
1283 force = cmd->obj.i32;
1284 error = sctp_gen_sack(asoc, force, commands);
1285 break;
1286
1287 case SCTP_CMD_PROCESS_SACK:
1288 /* Process an inbound SACK. */
1289 error = sctp_cmd_process_sack(commands, asoc,
1290 cmd->obj.ptr);
1291 break;
1292
1293 case SCTP_CMD_GEN_INIT_ACK:
1294 /* Generate an INIT ACK chunk. */
1295 new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC,
1296 0);
1297 if (!new_obj)
1298 goto nomem;
1299
1300 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1301 SCTP_CHUNK(new_obj));
1302 break;
1303
1304 case SCTP_CMD_PEER_INIT:
1305 /* Process a unified INIT from the peer.
1306 * Note: Only used during INIT-ACK processing. If
1307 * there is an error just return to the outter
1308 * layer which will bail.
1309 */
1310 error = sctp_cmd_process_init(commands, asoc, chunk,
1311 cmd->obj.ptr, gfp);
1312 break;
1313
1314 case SCTP_CMD_GEN_COOKIE_ECHO:
1315 /* Generate a COOKIE ECHO chunk. */
1316 new_obj = sctp_make_cookie_echo(asoc, chunk);
1317 if (!new_obj) {
1318 if (cmd->obj.ptr)
1319 sctp_chunk_free(cmd->obj.ptr);
1320 goto nomem;
1321 }
1322 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1323 SCTP_CHUNK(new_obj));
1324
1325 /* If there is an ERROR chunk to be sent along with
1326 * the COOKIE_ECHO, send it, too.
1327 */
1328 if (cmd->obj.ptr)
1329 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1330 SCTP_CHUNK(cmd->obj.ptr));
1331
1332 if (new_obj->transport) {
1333 new_obj->transport->init_sent_count++;
1334 asoc->init_last_sent_to = new_obj->transport;
1335 }
1336
1337 /* FIXME - Eventually come up with a cleaner way to
1338 * enabling COOKIE-ECHO + DATA bundling during
1339 * multihoming stale cookie scenarios, the following
1340 * command plays with asoc->peer.retran_path to
1341 * avoid the problem of sending the COOKIE-ECHO and
1342 * DATA in different paths, which could result
1343 * in the association being ABORTed if the DATA chunk
1344 * is processed first by the server. Checking the
1345 * init error counter simply causes this command
1346 * to be executed only during failed attempts of
1347 * association establishment.
1348 */
1349 if ((asoc->peer.retran_path !=
1350 asoc->peer.primary_path) &&
1351 (asoc->init_err_counter > 0)) {
1352 sctp_add_cmd_sf(commands,
1353 SCTP_CMD_FORCE_PRIM_RETRAN,
1354 SCTP_NULL());
1355 }
1356
1357 break;
1358
1359 case SCTP_CMD_GEN_SHUTDOWN:
1360 /* Generate SHUTDOWN when in SHUTDOWN_SENT state.
1361 * Reset error counts.
1362 */
1363 asoc->overall_error_count = 0;
1364
1365 /* Generate a SHUTDOWN chunk. */
1366 new_obj = sctp_make_shutdown(asoc, chunk);
1367 if (!new_obj)
1368 goto nomem;
1369 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1370 SCTP_CHUNK(new_obj));
1371 break;
1372
1373 case SCTP_CMD_CHUNK_ULP:
1374 /* Send a chunk to the sockets layer. */
1375 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1376 "chunk_up:", cmd->obj.ptr,
1377 "ulpq:", &asoc->ulpq);
1378 sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.ptr,
1379 GFP_ATOMIC);
1380 break;
1381
1382 case SCTP_CMD_EVENT_ULP:
1383 /* Send a notification to the sockets layer. */
1384 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1385 "event_up:",cmd->obj.ptr,
1386 "ulpq:",&asoc->ulpq);
1387 sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ptr);
1388 break;
1389
1390 case SCTP_CMD_REPLY:
1391 /* If an caller has not already corked, do cork. */
1392 if (!asoc->outqueue.cork) {
1393 sctp_outq_cork(&asoc->outqueue);
1394 local_cork = 1;
1395 }
1396 /* Send a chunk to our peer. */
1397 error = sctp_outq_tail(&asoc->outqueue, cmd->obj.ptr);
1398 break;
1399
1400 case SCTP_CMD_SEND_PKT:
1401 /* Send a full packet to our peer. */
1402 packet = cmd->obj.ptr;
1403 sctp_packet_transmit(packet);
1404 sctp_ootb_pkt_free(packet);
1405 break;
1406
1407 case SCTP_CMD_T1_RETRAN:
1408 /* Mark a transport for retransmission. */
1409 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1410 SCTP_RTXR_T1_RTX);
1411 break;
1412
1413 case SCTP_CMD_RETRAN:
1414 /* Mark a transport for retransmission. */
1415 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1416 SCTP_RTXR_T3_RTX);
1417 break;
1418
1419 case SCTP_CMD_TRANSMIT:
1420 /* Kick start transmission. */
1421 error = sctp_outq_uncork(&asoc->outqueue);
1422 local_cork = 0;
1423 break;
1424
1425 case SCTP_CMD_ECN_CE:
1426 /* Do delayed CE processing. */
1427 sctp_do_ecn_ce_work(asoc, cmd->obj.u32);
1428 break;
1429
1430 case SCTP_CMD_ECN_ECNE:
1431 /* Do delayed ECNE processing. */
1432 new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32,
1433 chunk);
1434 if (new_obj)
1435 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1436 SCTP_CHUNK(new_obj));
1437 break;
1438
1439 case SCTP_CMD_ECN_CWR:
1440 /* Do delayed CWR processing. */
1441 sctp_do_ecn_cwr_work(asoc, cmd->obj.u32);
1442 break;
1443
1444 case SCTP_CMD_SETUP_T2:
1445 sctp_cmd_setup_t2(commands, asoc, cmd->obj.ptr);
1446 break;
1447
1448 case SCTP_CMD_TIMER_START:
1449 timer = &asoc->timers[cmd->obj.to];
1450 timeout = asoc->timeouts[cmd->obj.to];
1451 BUG_ON(!timeout);
1452
1453 timer->expires = jiffies + timeout;
1454 sctp_association_hold(asoc);
1455 add_timer(timer);
1456 break;
1457
1458 case SCTP_CMD_TIMER_RESTART:
1459 timer = &asoc->timers[cmd->obj.to];
1460 timeout = asoc->timeouts[cmd->obj.to];
1461 if (!mod_timer(timer, jiffies + timeout))
1462 sctp_association_hold(asoc);
1463 break;
1464
1465 case SCTP_CMD_TIMER_STOP:
1466 timer = &asoc->timers[cmd->obj.to];
1467 if (timer_pending(timer) && del_timer(timer))
1468 sctp_association_put(asoc);
1469 break;
1470
1471 case SCTP_CMD_INIT_CHOOSE_TRANSPORT:
1472 chunk = cmd->obj.ptr;
1473 t = sctp_assoc_choose_alter_transport(asoc,
1474 asoc->init_last_sent_to);
1475 asoc->init_last_sent_to = t;
1476 chunk->transport = t;
1477 t->init_sent_count++;
1478 /* Set the new transport as primary */
1479 sctp_assoc_set_primary(asoc, t);
1480 break;
1481
1482 case SCTP_CMD_INIT_RESTART:
1483 /* Do the needed accounting and updates
1484 * associated with restarting an initialization
1485 * timer. Only multiply the timeout by two if
1486 * all transports have been tried at the current
1487 * timeout.
1488 */
1489 sctp_cmd_t1_timer_update(asoc,
1490 SCTP_EVENT_TIMEOUT_T1_INIT,
1491 "INIT");
1492
1493 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
1494 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
1495 break;
1496
1497 case SCTP_CMD_COOKIEECHO_RESTART:
1498 /* Do the needed accounting and updates
1499 * associated with restarting an initialization
1500 * timer. Only multiply the timeout by two if
1501 * all transports have been tried at the current
1502 * timeout.
1503 */
1504 sctp_cmd_t1_timer_update(asoc,
1505 SCTP_EVENT_TIMEOUT_T1_COOKIE,
1506 "COOKIE");
1507
1508 /* If we've sent any data bundled with
1509 * COOKIE-ECHO we need to resend.
1510 */
1511 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1512 transports) {
1513 sctp_retransmit_mark(&asoc->outqueue, t,
1514 SCTP_RTXR_T1_RTX);
1515 }
1516
1517 sctp_add_cmd_sf(commands,
1518 SCTP_CMD_TIMER_RESTART,
1519 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
1520 break;
1521
1522 case SCTP_CMD_INIT_FAILED:
1523 sctp_cmd_init_failed(commands, asoc, cmd->obj.err);
1524 break;
1525
1526 case SCTP_CMD_ASSOC_FAILED:
1527 sctp_cmd_assoc_failed(commands, asoc, event_type,
1528 subtype, chunk, cmd->obj.err);
1529 break;
1530
1531 case SCTP_CMD_INIT_COUNTER_INC:
1532 asoc->init_err_counter++;
1533 break;
1534
1535 case SCTP_CMD_INIT_COUNTER_RESET:
1536 asoc->init_err_counter = 0;
1537 asoc->init_cycle = 0;
1538 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1539 transports) {
1540 t->init_sent_count = 0;
1541 }
1542 break;
1543
1544 case SCTP_CMD_REPORT_DUP:
1545 sctp_tsnmap_mark_dup(&asoc->peer.tsn_map,
1546 cmd->obj.u32);
1547 break;
1548
1549 case SCTP_CMD_REPORT_BAD_TAG:
1550 SCTP_DEBUG_PRINTK("vtag mismatch!\n");
1551 break;
1552
1553 case SCTP_CMD_STRIKE:
1554 /* Mark one strike against a transport. */
1555 sctp_do_8_2_transport_strike(asoc, cmd->obj.transport,
1556 0);
1557 break;
1558
1559 case SCTP_CMD_TRANSPORT_IDLE:
1560 t = cmd->obj.transport;
1561 sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE);
1562 break;
1563
1564 case SCTP_CMD_TRANSPORT_HB_SENT:
1565 t = cmd->obj.transport;
1566 sctp_do_8_2_transport_strike(asoc, t, 1);
1567 t->hb_sent = 1;
1568 break;
1569
1570 case SCTP_CMD_TRANSPORT_ON:
1571 t = cmd->obj.transport;
1572 sctp_cmd_transport_on(commands, asoc, t, chunk);
1573 break;
1574
1575 case SCTP_CMD_HB_TIMERS_START:
1576 sctp_cmd_hb_timers_start(commands, asoc);
1577 break;
1578
1579 case SCTP_CMD_HB_TIMER_UPDATE:
1580 t = cmd->obj.transport;
1581 sctp_cmd_hb_timer_update(commands, t);
1582 break;
1583
1584 case SCTP_CMD_HB_TIMERS_STOP:
1585 sctp_cmd_hb_timers_stop(commands, asoc);
1586 break;
1587
1588 case SCTP_CMD_REPORT_ERROR:
1589 error = cmd->obj.error;
1590 break;
1591
1592 case SCTP_CMD_PROCESS_CTSN:
1593 /* Dummy up a SACK for processing. */
1594 sackh.cum_tsn_ack = cmd->obj.be32;
1595 sackh.a_rwnd = asoc->peer.rwnd +
1596 asoc->outqueue.outstanding_bytes;
1597 sackh.num_gap_ack_blocks = 0;
1598 sackh.num_dup_tsns = 0;
1599 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK,
1600 SCTP_SACKH(&sackh));
1601 break;
1602
1603 case SCTP_CMD_DISCARD_PACKET:
1604 /* We need to discard the whole packet.
1605 * Uncork the queue since there might be
1606 * responses pending
1607 */
1608 chunk->pdiscard = 1;
1609 if (asoc) {
1610 sctp_outq_uncork(&asoc->outqueue);
1611 local_cork = 0;
1612 }
1613 break;
1614
1615 case SCTP_CMD_RTO_PENDING:
1616 t = cmd->obj.transport;
1617 t->rto_pending = 1;
1618 break;
1619
1620 case SCTP_CMD_PART_DELIVER:
1621 sctp_ulpq_partial_delivery(&asoc->ulpq, cmd->obj.ptr,
1622 GFP_ATOMIC);
1623 break;
1624
1625 case SCTP_CMD_RENEGE:
1626 sctp_ulpq_renege(&asoc->ulpq, cmd->obj.ptr,
1627 GFP_ATOMIC);
1628 break;
1629
1630 case SCTP_CMD_SETUP_T4:
1631 sctp_cmd_setup_t4(commands, asoc, cmd->obj.ptr);
1632 break;
1633
1634 case SCTP_CMD_PROCESS_OPERR:
1635 sctp_cmd_process_operr(commands, asoc, chunk);
1636 break;
1637 case SCTP_CMD_CLEAR_INIT_TAG:
1638 asoc->peer.i.init_tag = 0;
1639 break;
1640 case SCTP_CMD_DEL_NON_PRIMARY:
1641 sctp_cmd_del_non_primary(asoc);
1642 break;
1643 case SCTP_CMD_T3_RTX_TIMERS_STOP:
1644 sctp_cmd_t3_rtx_timers_stop(commands, asoc);
1645 break;
1646 case SCTP_CMD_FORCE_PRIM_RETRAN:
1647 t = asoc->peer.retran_path;
1648 asoc->peer.retran_path = asoc->peer.primary_path;
1649 error = sctp_outq_uncork(&asoc->outqueue);
1650 local_cork = 0;
1651 asoc->peer.retran_path = t;
1652 break;
1653 case SCTP_CMD_SET_SK_ERR:
1654 sctp_cmd_set_sk_err(asoc, cmd->obj.error);
1655 break;
1656 case SCTP_CMD_ASSOC_CHANGE:
1657 sctp_cmd_assoc_change(commands, asoc,
1658 cmd->obj.u8);
1659 break;
1660 case SCTP_CMD_ADAPTATION_IND:
1661 sctp_cmd_adaptation_ind(commands, asoc);
1662 break;
1663
1664 case SCTP_CMD_ASSOC_SHKEY:
1665 error = sctp_auth_asoc_init_active_key(asoc,
1666 GFP_ATOMIC);
1667 break;
1668 case SCTP_CMD_UPDATE_INITTAG:
1669 asoc->peer.i.init_tag = cmd->obj.u32;
1670 break;
1671 case SCTP_CMD_SEND_MSG:
1672 if (!asoc->outqueue.cork) {
1673 sctp_outq_cork(&asoc->outqueue);
1674 local_cork = 1;
1675 }
1676 error = sctp_cmd_send_msg(asoc, cmd->obj.msg);
1677 break;
1678 case SCTP_CMD_SEND_NEXT_ASCONF:
1679 sctp_cmd_send_asconf(asoc);
1680 break;
1681 default:
1682 printk(KERN_WARNING "Impossible command: %u, %p\n",
1683 cmd->verb, cmd->obj.ptr);
1684 break;
1685 }
1686
1687 if (error)
1688 break;
1689 }
1690
1691 out:
1692 /* If this is in response to a received chunk, wait until
1693 * we are done with the packet to open the queue so that we don't
1694 * send multiple packets in response to a single request.
1695 */
1696 if (asoc && SCTP_EVENT_T_CHUNK == event_type && chunk) {
1697 if (chunk->end_of_packet || chunk->singleton)
1698 error = sctp_outq_uncork(&asoc->outqueue);
1699 } else if (local_cork)
1700 error = sctp_outq_uncork(&asoc->outqueue);
1701 return error;
1702 nomem:
1703 error = -ENOMEM;
1704 goto out;
1705 }
1706
linux-next