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ext4: use kmem_cache_zalloc() in ext4_init_io_end()
[zen-stable.git] / net / sctp / sm_sideeffect.c
blobb21b218d564f20f9f9b04e39412a0499377d8d62
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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
51
52 #include <linux/skbuff.h>
53 #include <linux/types.h>
54 #include <linux/socket.h>
55 #include <linux/ip.h>
56 #include <linux/gfp.h>
57 #include <net/sock.h>
58 #include <net/sctp/sctp.h>
59 #include <net/sctp/sm.h>
60
61 static int sctp_cmd_interpreter(sctp_event_t event_type,
62 sctp_subtype_t subtype,
63 sctp_state_t state,
64 struct sctp_endpoint *ep,
65 struct sctp_association *asoc,
66 void *event_arg,
67 sctp_disposition_t status,
68 sctp_cmd_seq_t *commands,
69 gfp_t gfp);
70 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
71 sctp_state_t state,
72 struct sctp_endpoint *ep,
73 struct sctp_association *asoc,
74 void *event_arg,
75 sctp_disposition_t status,
76 sctp_cmd_seq_t *commands,
77 gfp_t gfp);
78
79 /********************************************************************
80 * Helper functions
81 ********************************************************************/
82
83 /* A helper function for delayed processing of INET ECN CE bit. */
84 static void sctp_do_ecn_ce_work(struct sctp_association *asoc,
85 __u32 lowest_tsn)
86 {
87 /* Save the TSN away for comparison when we receive CWR */
88
89 asoc->last_ecne_tsn = lowest_tsn;
90 asoc->need_ecne = 1;
91 }
92
93 /* Helper function for delayed processing of SCTP ECNE chunk. */
94 /* RFC 2960 Appendix A
95 *
96 * RFC 2481 details a specific bit for a sender to send in
97 * the header of its next outbound TCP segment to indicate to
98 * its peer that it has reduced its congestion window. This
99 * is termed the CWR bit. For SCTP the same indication is made
100 * by including the CWR chunk. This chunk contains one data
101 * element, i.e. the TSN number that was sent in the ECNE chunk.
102 * This element represents the lowest TSN number in the datagram
103 * that was originally marked with the CE bit.
104 */
105 static struct sctp_chunk *sctp_do_ecn_ecne_work(struct sctp_association *asoc,
106 __u32 lowest_tsn,
107 struct sctp_chunk *chunk)
108 {
109 struct sctp_chunk *repl;
110
111 /* Our previously transmitted packet ran into some congestion
112 * so we should take action by reducing cwnd and ssthresh
113 * and then ACK our peer that we we've done so by
114 * sending a CWR.
115 */
116
117 /* First, try to determine if we want to actually lower
118 * our cwnd variables. Only lower them if the ECNE looks more
119 * recent than the last response.
120 */
121 if (TSN_lt(asoc->last_cwr_tsn, lowest_tsn)) {
122 struct sctp_transport *transport;
123
124 /* Find which transport's congestion variables
125 * need to be adjusted.
126 */
127 transport = sctp_assoc_lookup_tsn(asoc, lowest_tsn);
128
129 /* Update the congestion variables. */
130 if (transport)
131 sctp_transport_lower_cwnd(transport,
132 SCTP_LOWER_CWND_ECNE);
133 asoc->last_cwr_tsn = lowest_tsn;
134 }
135
136 /* Always try to quiet the other end. In case of lost CWR,
137 * resend last_cwr_tsn.
138 */
139 repl = sctp_make_cwr(asoc, asoc->last_cwr_tsn, chunk);
140
141 /* If we run out of memory, it will look like a lost CWR. We'll
142 * get back in sync eventually.
143 */
144 return repl;
145 }
146
147 /* Helper function to do delayed processing of ECN CWR chunk. */
148 static void sctp_do_ecn_cwr_work(struct sctp_association *asoc,
149 __u32 lowest_tsn)
150 {
151 /* Turn off ECNE getting auto-prepended to every outgoing
152 * packet
153 */
154 asoc->need_ecne = 0;
155 }
156
157 /* Generate SACK if necessary. We call this at the end of a packet. */
158 static int sctp_gen_sack(struct sctp_association *asoc, int force,
159 sctp_cmd_seq_t *commands)
160 {
161 __u32 ctsn, max_tsn_seen;
162 struct sctp_chunk *sack;
163 struct sctp_transport *trans = asoc->peer.last_data_from;
164 int error = 0;
165
166 if (force ||
167 (!trans && (asoc->param_flags & SPP_SACKDELAY_DISABLE)) ||
168 (trans && (trans->param_flags & SPP_SACKDELAY_DISABLE)))
169 asoc->peer.sack_needed = 1;
170
171 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
172 max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
173
174 /* From 12.2 Parameters necessary per association (i.e. the TCB):
175 *
176 * Ack State : This flag indicates if the next received packet
177 * : is to be responded to with a SACK. ...
178 * : When DATA chunks are out of order, SACK's
179 * : are not delayed (see Section 6).
180 *
181 * [This is actually not mentioned in Section 6, but we
182 * implement it here anyway. --piggy]
183 */
184 if (max_tsn_seen != ctsn)
185 asoc->peer.sack_needed = 1;
186
187 /* From 6.2 Acknowledgement on Reception of DATA Chunks:
188 *
189 * Section 4.2 of [RFC2581] SHOULD be followed. Specifically,
190 * an acknowledgement SHOULD be generated for at least every
191 * second packet (not every second DATA chunk) received, and
192 * SHOULD be generated within 200 ms of the arrival of any
193 * unacknowledged DATA chunk. ...
194 */
195 if (!asoc->peer.sack_needed) {
196 asoc->peer.sack_cnt++;
197
198 /* Set the SACK delay timeout based on the
199 * SACK delay for the last transport
200 * data was received from, or the default
201 * for the association.
202 */
203 if (trans) {
204 /* We will need a SACK for the next packet. */
205 if (asoc->peer.sack_cnt >= trans->sackfreq - 1)
206 asoc->peer.sack_needed = 1;
207
208 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
209 trans->sackdelay;
210 } else {
211 /* We will need a SACK for the next packet. */
212 if (asoc->peer.sack_cnt >= asoc->sackfreq - 1)
213 asoc->peer.sack_needed = 1;
214
215 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
216 asoc->sackdelay;
217 }
218
219 /* Restart the SACK timer. */
220 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
221 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
222 } else {
223 asoc->a_rwnd = asoc->rwnd;
224 sack = sctp_make_sack(asoc);
225 if (!sack)
226 goto nomem;
227
228 asoc->peer.sack_needed = 0;
229 asoc->peer.sack_cnt = 0;
230
231 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(sack));
232
233 /* Stop the SACK timer. */
234 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
235 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
236 }
237
238 return error;
239 nomem:
240 error = -ENOMEM;
241 return error;
242 }
243
244 /* When the T3-RTX timer expires, it calls this function to create the
245 * relevant state machine event.
246 */
247 void sctp_generate_t3_rtx_event(unsigned long peer)
248 {
249 int error;
250 struct sctp_transport *transport = (struct sctp_transport *) peer;
251 struct sctp_association *asoc = transport->asoc;
252
253 /* Check whether a task is in the sock. */
254
255 sctp_bh_lock_sock(asoc->base.sk);
256 if (sock_owned_by_user(asoc->base.sk)) {
257 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
258
259 /* Try again later. */
260 if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20)))
261 sctp_transport_hold(transport);
262 goto out_unlock;
263 }
264
265 /* Is this transport really dead and just waiting around for
266 * the timer to let go of the reference?
267 */
268 if (transport->dead)
269 goto out_unlock;
270
271 /* Run through the state machine. */
272 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
273 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX),
274 asoc->state,
275 asoc->ep, asoc,
276 transport, GFP_ATOMIC);
277
278 if (error)
279 asoc->base.sk->sk_err = -error;
280
281 out_unlock:
282 sctp_bh_unlock_sock(asoc->base.sk);
283 sctp_transport_put(transport);
284 }
285
286 /* This is a sa interface for producing timeout events. It works
287 * for timeouts which use the association as their parameter.
288 */
289 static void sctp_generate_timeout_event(struct sctp_association *asoc,
290 sctp_event_timeout_t timeout_type)
291 {
292 int error = 0;
293
294 sctp_bh_lock_sock(asoc->base.sk);
295 if (sock_owned_by_user(asoc->base.sk)) {
296 SCTP_DEBUG_PRINTK("%s:Sock is busy: timer %d\n",
297 __func__,
298 timeout_type);
299
300 /* Try again later. */
301 if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20)))
302 sctp_association_hold(asoc);
303 goto out_unlock;
304 }
305
306 /* Is this association really dead and just waiting around for
307 * the timer to let go of the reference?
308 */
309 if (asoc->base.dead)
310 goto out_unlock;
311
312 /* Run through the state machine. */
313 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
314 SCTP_ST_TIMEOUT(timeout_type),
315 asoc->state, asoc->ep, asoc,
316 (void *)timeout_type, GFP_ATOMIC);
317
318 if (error)
319 asoc->base.sk->sk_err = -error;
320
321 out_unlock:
322 sctp_bh_unlock_sock(asoc->base.sk);
323 sctp_association_put(asoc);
324 }
325
326 static void sctp_generate_t1_cookie_event(unsigned long data)
327 {
328 struct sctp_association *asoc = (struct sctp_association *) data;
329 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE);
330 }
331
332 static void sctp_generate_t1_init_event(unsigned long data)
333 {
334 struct sctp_association *asoc = (struct sctp_association *) data;
335 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT);
336 }
337
338 static void sctp_generate_t2_shutdown_event(unsigned long data)
339 {
340 struct sctp_association *asoc = (struct sctp_association *) data;
341 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN);
342 }
343
344 static void sctp_generate_t4_rto_event(unsigned long data)
345 {
346 struct sctp_association *asoc = (struct sctp_association *) data;
347 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO);
348 }
349
350 static void sctp_generate_t5_shutdown_guard_event(unsigned long data)
351 {
352 struct sctp_association *asoc = (struct sctp_association *)data;
353 sctp_generate_timeout_event(asoc,
354 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD);
355
356 } /* sctp_generate_t5_shutdown_guard_event() */
357
358 static void sctp_generate_autoclose_event(unsigned long data)
359 {
360 struct sctp_association *asoc = (struct sctp_association *) data;
361 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE);
362 }
363
364 /* Generate a heart beat event. If the sock is busy, reschedule. Make
365 * sure that the transport is still valid.
366 */
367 void sctp_generate_heartbeat_event(unsigned long data)
368 {
369 int error = 0;
370 struct sctp_transport *transport = (struct sctp_transport *) data;
371 struct sctp_association *asoc = transport->asoc;
372
373 sctp_bh_lock_sock(asoc->base.sk);
374 if (sock_owned_by_user(asoc->base.sk)) {
375 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
376
377 /* Try again later. */
378 if (!mod_timer(&transport->hb_timer, jiffies + (HZ/20)))
379 sctp_transport_hold(transport);
380 goto out_unlock;
381 }
382
383 /* Is this structure just waiting around for us to actually
384 * get destroyed?
385 */
386 if (transport->dead)
387 goto out_unlock;
388
389 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
390 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT),
391 asoc->state, asoc->ep, asoc,
392 transport, GFP_ATOMIC);
393
394 if (error)
395 asoc->base.sk->sk_err = -error;
396
397 out_unlock:
398 sctp_bh_unlock_sock(asoc->base.sk);
399 sctp_transport_put(transport);
400 }
401
402 /* Handle the timeout of the ICMP protocol unreachable timer. Trigger
403 * the correct state machine transition that will close the association.
404 */
405 void sctp_generate_proto_unreach_event(unsigned long data)
406 {
407 struct sctp_transport *transport = (struct sctp_transport *) data;
408 struct sctp_association *asoc = transport->asoc;
409
410 sctp_bh_lock_sock(asoc->base.sk);
411 if (sock_owned_by_user(asoc->base.sk)) {
412 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
413
414 /* Try again later. */
415 if (!mod_timer(&transport->proto_unreach_timer,
416 jiffies + (HZ/20)))
417 sctp_association_hold(asoc);
418 goto out_unlock;
419 }
420
421 /* Is this structure just waiting around for us to actually
422 * get destroyed?
423 */
424 if (asoc->base.dead)
425 goto out_unlock;
426
427 sctp_do_sm(SCTP_EVENT_T_OTHER,
428 SCTP_ST_OTHER(SCTP_EVENT_ICMP_PROTO_UNREACH),
429 asoc->state, asoc->ep, asoc, transport, GFP_ATOMIC);
430
431 out_unlock:
432 sctp_bh_unlock_sock(asoc->base.sk);
433 sctp_association_put(asoc);
434 }
435
436
437 /* Inject a SACK Timeout event into the state machine. */
438 static void sctp_generate_sack_event(unsigned long data)
439 {
440 struct sctp_association *asoc = (struct sctp_association *) data;
441 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK);
442 }
443
444 sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = {
445 NULL,
446 sctp_generate_t1_cookie_event,
447 sctp_generate_t1_init_event,
448 sctp_generate_t2_shutdown_event,
449 NULL,
450 sctp_generate_t4_rto_event,
451 sctp_generate_t5_shutdown_guard_event,
452 NULL,
453 sctp_generate_sack_event,
454 sctp_generate_autoclose_event,
455 };
456
457
458 /* RFC 2960 8.2 Path Failure Detection
459 *
460 * When its peer endpoint is multi-homed, an endpoint should keep a
461 * error counter for each of the destination transport addresses of the
462 * peer endpoint.
463 *
464 * Each time the T3-rtx timer expires on any address, or when a
465 * HEARTBEAT sent to an idle address is not acknowledged within a RTO,
466 * the error counter of that destination address will be incremented.
467 * When the value in the error counter exceeds the protocol parameter
468 * 'Path.Max.Retrans' of that destination address, the endpoint should
469 * mark the destination transport address as inactive, and a
470 * notification SHOULD be sent to the upper layer.
471 *
472 */
473 static void sctp_do_8_2_transport_strike(struct sctp_association *asoc,
474 struct sctp_transport *transport,
475 int is_hb)
476 {
477 /* The check for association's overall error counter exceeding the
478 * threshold is done in the state function.
479 */
480 /* We are here due to a timer expiration. If the timer was
481 * not a HEARTBEAT, then normal error tracking is done.
482 * If the timer was a heartbeat, we only increment error counts
483 * when we already have an outstanding HEARTBEAT that has not
484 * been acknowledged.
485 * Additionaly, some tranport states inhibit error increments.
486 */
487 if (!is_hb) {
488 asoc->overall_error_count++;
489 if (transport->state != SCTP_INACTIVE)
490 transport->error_count++;
491 } else if (transport->hb_sent) {
492 if (transport->state != SCTP_UNCONFIRMED)
493 asoc->overall_error_count++;
494 if (transport->state != SCTP_INACTIVE)
495 transport->error_count++;
496 }
497
498 if (transport->state != SCTP_INACTIVE &&
499 (transport->error_count > transport->pathmaxrxt)) {
500 SCTP_DEBUG_PRINTK_IPADDR("transport_strike:association %p",
501 " transport IP: port:%d failed.\n",
502 asoc,
503 (&transport->ipaddr),
504 ntohs(transport->ipaddr.v4.sin_port));
505 sctp_assoc_control_transport(asoc, transport,
506 SCTP_TRANSPORT_DOWN,
507 SCTP_FAILED_THRESHOLD);
508 }
509
510 /* E2) For the destination address for which the timer
511 * expires, set RTO <- RTO * 2 ("back off the timer"). The
512 * maximum value discussed in rule C7 above (RTO.max) may be
513 * used to provide an upper bound to this doubling operation.
514 *
515 * Special Case: the first HB doesn't trigger exponential backoff.
516 * The first unacknowledged HB triggers it. We do this with a flag
517 * that indicates that we have an outstanding HB.
518 */
519 if (!is_hb || transport->hb_sent) {
520 transport->rto = min((transport->rto * 2), transport->asoc->rto_max);
521 }
522 }
523
524 /* Worker routine to handle INIT command failure. */
525 static void sctp_cmd_init_failed(sctp_cmd_seq_t *commands,
526 struct sctp_association *asoc,
527 unsigned error)
528 {
529 struct sctp_ulpevent *event;
530
531 event = sctp_ulpevent_make_assoc_change(asoc,0, SCTP_CANT_STR_ASSOC,
532 (__u16)error, 0, 0, NULL,
533 GFP_ATOMIC);
534
535 if (event)
536 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
537 SCTP_ULPEVENT(event));
538
539 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
540 SCTP_STATE(SCTP_STATE_CLOSED));
541
542 /* SEND_FAILED sent later when cleaning up the association. */
543 asoc->outqueue.error = error;
544 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
545 }
546
547 /* Worker routine to handle SCTP_CMD_ASSOC_FAILED. */
548 static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands,
549 struct sctp_association *asoc,
550 sctp_event_t event_type,
551 sctp_subtype_t subtype,
552 struct sctp_chunk *chunk,
553 unsigned error)
554 {
555 struct sctp_ulpevent *event;
556
557 /* Cancel any partial delivery in progress. */
558 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
559
560 if (event_type == SCTP_EVENT_T_CHUNK && subtype.chunk == SCTP_CID_ABORT)
561 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
562 (__u16)error, 0, 0, chunk,
563 GFP_ATOMIC);
564 else
565 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
566 (__u16)error, 0, 0, NULL,
567 GFP_ATOMIC);
568 if (event)
569 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
570 SCTP_ULPEVENT(event));
571
572 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
573 SCTP_STATE(SCTP_STATE_CLOSED));
574
575 /* SEND_FAILED sent later when cleaning up the association. */
576 asoc->outqueue.error = error;
577 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
578 }
579
580 /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT
581 * inside the cookie. In reality, this is only used for INIT-ACK processing
582 * since all other cases use "temporary" associations and can do all
583 * their work in statefuns directly.
584 */
585 static int sctp_cmd_process_init(sctp_cmd_seq_t *commands,
586 struct sctp_association *asoc,
587 struct sctp_chunk *chunk,
588 sctp_init_chunk_t *peer_init,
589 gfp_t gfp)
590 {
591 int error;
592
593 /* We only process the init as a sideeffect in a single
594 * case. This is when we process the INIT-ACK. If we
595 * fail during INIT processing (due to malloc problems),
596 * just return the error and stop processing the stack.
597 */
598 if (!sctp_process_init(asoc, chunk->chunk_hdr->type,
599 sctp_source(chunk), peer_init, gfp))
600 error = -ENOMEM;
601 else
602 error = 0;
603
604 return error;
605 }
606
607 /* Helper function to break out starting up of heartbeat timers. */
608 static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds,
609 struct sctp_association *asoc)
610 {
611 struct sctp_transport *t;
612
613 /* Start a heartbeat timer for each transport on the association.
614 * hold a reference on the transport to make sure none of
615 * the needed data structures go away.
616 */
617 list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) {
618
619 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
620 sctp_transport_hold(t);
621 }
622 }
623
624 static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds,
625 struct sctp_association *asoc)
626 {
627 struct sctp_transport *t;
628
629 /* Stop all heartbeat timers. */
630
631 list_for_each_entry(t, &asoc->peer.transport_addr_list,
632 transports) {
633 if (del_timer(&t->hb_timer))
634 sctp_transport_put(t);
635 }
636 }
637
638 /* Helper function to stop any pending T3-RTX timers */
639 static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds,
640 struct sctp_association *asoc)
641 {
642 struct sctp_transport *t;
643
644 list_for_each_entry(t, &asoc->peer.transport_addr_list,
645 transports) {
646 if (timer_pending(&t->T3_rtx_timer) &&
647 del_timer(&t->T3_rtx_timer)) {
648 sctp_transport_put(t);
649 }
650 }
651 }
652
653
654 /* Helper function to update the heartbeat timer. */
655 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds,
656 struct sctp_transport *t)
657 {
658 /* Update the heartbeat timer. */
659 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
660 sctp_transport_hold(t);
661 }
662
663 /* Helper function to handle the reception of an HEARTBEAT ACK. */
664 static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds,
665 struct sctp_association *asoc,
666 struct sctp_transport *t,
667 struct sctp_chunk *chunk)
668 {
669 sctp_sender_hb_info_t *hbinfo;
670
671 /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the
672 * HEARTBEAT should clear the error counter of the destination
673 * transport address to which the HEARTBEAT was sent.
674 * The association's overall error count is also cleared.
675 */
676 t->error_count = 0;
677 t->asoc->overall_error_count = 0;
678
679 /* Clear the hb_sent flag to signal that we had a good
680 * acknowledgement.
681 */
682 t->hb_sent = 0;
683
684 /* Mark the destination transport address as active if it is not so
685 * marked.
686 */
687 if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED))
688 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
689 SCTP_HEARTBEAT_SUCCESS);
690
691 /* The receiver of the HEARTBEAT ACK should also perform an
692 * RTT measurement for that destination transport address
693 * using the time value carried in the HEARTBEAT ACK chunk.
694 * If the transport's rto_pending variable has been cleared,
695 * it was most likely due to a retransmit. However, we want
696 * to re-enable it to properly update the rto.
697 */
698 if (t->rto_pending == 0)
699 t->rto_pending = 1;
700
701 hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data;
702 sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at));
703
704 /* Update the heartbeat timer. */
705 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
706 sctp_transport_hold(t);
707 }
708
709
710 /* Helper function to process the process SACK command. */
711 static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds,
712 struct sctp_association *asoc,
713 struct sctp_sackhdr *sackh)
714 {
715 int err = 0;
716
717 if (sctp_outq_sack(&asoc->outqueue, sackh)) {
718 /* There are no more TSNs awaiting SACK. */
719 err = sctp_do_sm(SCTP_EVENT_T_OTHER,
720 SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN),
721 asoc->state, asoc->ep, asoc, NULL,
722 GFP_ATOMIC);
723 }
724
725 return err;
726 }
727
728 /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set
729 * the transport for a shutdown chunk.
730 */
731 static void sctp_cmd_setup_t2(sctp_cmd_seq_t *cmds,
732 struct sctp_association *asoc,
733 struct sctp_chunk *chunk)
734 {
735 struct sctp_transport *t;
736
737 if (chunk->transport)
738 t = chunk->transport;
739 else {
740 t = sctp_assoc_choose_alter_transport(asoc,
741 asoc->shutdown_last_sent_to);
742 chunk->transport = t;
743 }
744 asoc->shutdown_last_sent_to = t;
745 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto;
746 }
747
748 /* Helper function to change the state of an association. */
749 static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds,
750 struct sctp_association *asoc,
751 sctp_state_t state)
752 {
753 struct sock *sk = asoc->base.sk;
754
755 asoc->state = state;
756
757 SCTP_DEBUG_PRINTK("sctp_cmd_new_state: asoc %p[%s]\n",
758 asoc, sctp_state_tbl[state]);
759
760 if (sctp_style(sk, TCP)) {
761 /* Change the sk->sk_state of a TCP-style socket that has
762 * successfully completed a connect() call.
763 */
764 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED))
765 sk->sk_state = SCTP_SS_ESTABLISHED;
766
767 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */
768 if (sctp_state(asoc, SHUTDOWN_RECEIVED) &&
769 sctp_sstate(sk, ESTABLISHED))
770 sk->sk_shutdown |= RCV_SHUTDOWN;
771 }
772
773 if (sctp_state(asoc, COOKIE_WAIT)) {
774 /* Reset init timeouts since they may have been
775 * increased due to timer expirations.
776 */
777 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
778 asoc->rto_initial;
779 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
780 asoc->rto_initial;
781 }
782
783 if (sctp_state(asoc, ESTABLISHED) ||
784 sctp_state(asoc, CLOSED) ||
785 sctp_state(asoc, SHUTDOWN_RECEIVED)) {
786 /* Wake up any processes waiting in the asoc's wait queue in
787 * sctp_wait_for_connect() or sctp_wait_for_sndbuf().
788 */
789 if (waitqueue_active(&asoc->wait))
790 wake_up_interruptible(&asoc->wait);
791
792 /* Wake up any processes waiting in the sk's sleep queue of
793 * a TCP-style or UDP-style peeled-off socket in
794 * sctp_wait_for_accept() or sctp_wait_for_packet().
795 * For a UDP-style socket, the waiters are woken up by the
796 * notifications.
797 */
798 if (!sctp_style(sk, UDP))
799 sk->sk_state_change(sk);
800 }
801 }
802
803 /* Helper function to delete an association. */
804 static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds,
805 struct sctp_association *asoc)
806 {
807 struct sock *sk = asoc->base.sk;
808
809 /* If it is a non-temporary association belonging to a TCP-style
810 * listening socket that is not closed, do not free it so that accept()
811 * can pick it up later.
812 */
813 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) &&
814 (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK))
815 return;
816
817 sctp_unhash_established(asoc);
818 sctp_association_free(asoc);
819 }
820
821 /*
822 * ADDIP Section 4.1 ASCONF Chunk Procedures
823 * A4) Start a T-4 RTO timer, using the RTO value of the selected
824 * destination address (we use active path instead of primary path just
825 * because primary path may be inactive.
826 */
827 static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds,
828 struct sctp_association *asoc,
829 struct sctp_chunk *chunk)
830 {
831 struct sctp_transport *t;
832
833 t = sctp_assoc_choose_alter_transport(asoc, chunk->transport);
834 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto;
835 chunk->transport = t;
836 }
837
838 /* Process an incoming Operation Error Chunk. */
839 static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds,
840 struct sctp_association *asoc,
841 struct sctp_chunk *chunk)
842 {
843 struct sctp_errhdr *err_hdr;
844 struct sctp_ulpevent *ev;
845
846 while (chunk->chunk_end > chunk->skb->data) {
847 err_hdr = (struct sctp_errhdr *)(chunk->skb->data);
848
849 ev = sctp_ulpevent_make_remote_error(asoc, chunk, 0,
850 GFP_ATOMIC);
851 if (!ev)
852 return;
853
854 sctp_ulpq_tail_event(&asoc->ulpq, ev);
855
856 switch (err_hdr->cause) {
857 case SCTP_ERROR_UNKNOWN_CHUNK:
858 {
859 sctp_chunkhdr_t *unk_chunk_hdr;
860
861 unk_chunk_hdr = (sctp_chunkhdr_t *)err_hdr->variable;
862 switch (unk_chunk_hdr->type) {
863 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with
864 * an ERROR chunk reporting that it did not recognized
865 * the ASCONF chunk type, the sender of the ASCONF MUST
866 * NOT send any further ASCONF chunks and MUST stop its
867 * T-4 timer.
868 */
869 case SCTP_CID_ASCONF:
870 if (asoc->peer.asconf_capable == 0)
871 break;
872
873 asoc->peer.asconf_capable = 0;
874 sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP,
875 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
876 break;
877 default:
878 break;
879 }
880 break;
881 }
882 default:
883 break;
884 }
885 }
886 }
887
888 /* Process variable FWDTSN chunk information. */
889 static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq,
890 struct sctp_chunk *chunk)
891 {
892 struct sctp_fwdtsn_skip *skip;
893 /* Walk through all the skipped SSNs */
894 sctp_walk_fwdtsn(skip, chunk) {
895 sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn));
896 }
897 }
898
899 /* Helper function to remove the association non-primary peer
900 * transports.
901 */
902 static void sctp_cmd_del_non_primary(struct sctp_association *asoc)
903 {
904 struct sctp_transport *t;
905 struct list_head *pos;
906 struct list_head *temp;
907
908 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
909 t = list_entry(pos, struct sctp_transport, transports);
910 if (!sctp_cmp_addr_exact(&t->ipaddr,
911 &asoc->peer.primary_addr)) {
912 sctp_assoc_del_peer(asoc, &t->ipaddr);
913 }
914 }
915 }
916
917 /* Helper function to set sk_err on a 1-1 style socket. */
918 static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error)
919 {
920 struct sock *sk = asoc->base.sk;
921
922 if (!sctp_style(sk, UDP))
923 sk->sk_err = error;
924 }
925
926 /* Helper function to generate an association change event */
927 static void sctp_cmd_assoc_change(sctp_cmd_seq_t *commands,
928 struct sctp_association *asoc,
929 u8 state)
930 {
931 struct sctp_ulpevent *ev;
932
933 ev = sctp_ulpevent_make_assoc_change(asoc, 0, state, 0,
934 asoc->c.sinit_num_ostreams,
935 asoc->c.sinit_max_instreams,
936 NULL, GFP_ATOMIC);
937 if (ev)
938 sctp_ulpq_tail_event(&asoc->ulpq, ev);
939 }
940
941 /* Helper function to generate an adaptation indication event */
942 static void sctp_cmd_adaptation_ind(sctp_cmd_seq_t *commands,
943 struct sctp_association *asoc)
944 {
945 struct sctp_ulpevent *ev;
946
947 ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC);
948
949 if (ev)
950 sctp_ulpq_tail_event(&asoc->ulpq, ev);
951 }
952
953
954 static void sctp_cmd_t1_timer_update(struct sctp_association *asoc,
955 sctp_event_timeout_t timer,
956 char *name)
957 {
958 struct sctp_transport *t;
959
960 t = asoc->init_last_sent_to;
961 asoc->init_err_counter++;
962
963 if (t->init_sent_count > (asoc->init_cycle + 1)) {
964 asoc->timeouts[timer] *= 2;
965 if (asoc->timeouts[timer] > asoc->max_init_timeo) {
966 asoc->timeouts[timer] = asoc->max_init_timeo;
967 }
968 asoc->init_cycle++;
969 SCTP_DEBUG_PRINTK(
970 "T1 %s Timeout adjustment"
971 " init_err_counter: %d"
972 " cycle: %d"
973 " timeout: %ld\n",
974 name,
975 asoc->init_err_counter,
976 asoc->init_cycle,
977 asoc->timeouts[timer]);
978 }
979
980 }
981
982 /* Send the whole message, chunk by chunk, to the outqueue.
983 * This way the whole message is queued up and bundling if
984 * encouraged for small fragments.
985 */
986 static int sctp_cmd_send_msg(struct sctp_association *asoc,
987 struct sctp_datamsg *msg)
988 {
989 struct sctp_chunk *chunk;
990 int error = 0;
991
992 list_for_each_entry(chunk, &msg->chunks, frag_list) {
993 error = sctp_outq_tail(&asoc->outqueue, chunk);
994 if (error)
995 break;
996 }
997
998 return error;
999 }
1000
1001
1002 /* Sent the next ASCONF packet currently stored in the association.
1003 * This happens after the ASCONF_ACK was succeffully processed.
1004 */
1005 static void sctp_cmd_send_asconf(struct sctp_association *asoc)
1006 {
1007 /* Send the next asconf chunk from the addip chunk
1008 * queue.
1009 */
1010 if (!list_empty(&asoc->addip_chunk_list)) {
1011 struct list_head *entry = asoc->addip_chunk_list.next;
1012 struct sctp_chunk *asconf = list_entry(entry,
1013 struct sctp_chunk, list);
1014 list_del_init(entry);
1015
1016 /* Hold the chunk until an ASCONF_ACK is received. */
1017 sctp_chunk_hold(asconf);
1018 if (sctp_primitive_ASCONF(asoc, asconf))
1019 sctp_chunk_free(asconf);
1020 else
1021 asoc->addip_last_asconf = asconf;
1022 }
1023 }
1024
1025
1026 /* These three macros allow us to pull the debugging code out of the
1027 * main flow of sctp_do_sm() to keep attention focused on the real
1028 * functionality there.
1029 */
1030 #define DEBUG_PRE \
1031 SCTP_DEBUG_PRINTK("sctp_do_sm prefn: " \
1032 "ep %p, %s, %s, asoc %p[%s], %s\n", \
1033 ep, sctp_evttype_tbl[event_type], \
1034 (*debug_fn)(subtype), asoc, \
1035 sctp_state_tbl[state], state_fn->name)
1036
1037 #define DEBUG_POST \
1038 SCTP_DEBUG_PRINTK("sctp_do_sm postfn: " \
1039 "asoc %p, status: %s\n", \
1040 asoc, sctp_status_tbl[status])
1041
1042 #define DEBUG_POST_SFX \
1043 SCTP_DEBUG_PRINTK("sctp_do_sm post sfx: error %d, asoc %p[%s]\n", \
1044 error, asoc, \
1045 sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \
1046 sctp_assoc2id(asoc)))?asoc->state:SCTP_STATE_CLOSED])
1047
1048 /*
1049 * This is the master state machine processing function.
1050 *
1051 * If you want to understand all of lksctp, this is a
1052 * good place to start.
1053 */
1054 int sctp_do_sm(sctp_event_t event_type, sctp_subtype_t subtype,
1055 sctp_state_t state,
1056 struct sctp_endpoint *ep,
1057 struct sctp_association *asoc,
1058 void *event_arg,
1059 gfp_t gfp)
1060 {
1061 sctp_cmd_seq_t commands;
1062 const sctp_sm_table_entry_t *state_fn;
1063 sctp_disposition_t status;
1064 int error = 0;
1065 typedef const char *(printfn_t)(sctp_subtype_t);
1066
1067 static printfn_t *table[] = {
1068 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname,
1069 };
1070 printfn_t *debug_fn __attribute__ ((unused)) = table[event_type];
1071
1072 /* Look up the state function, run it, and then process the
1073 * side effects. These three steps are the heart of lksctp.
1074 */
1075 state_fn = sctp_sm_lookup_event(event_type, state, subtype);
1076
1077 sctp_init_cmd_seq(&commands);
1078
1079 DEBUG_PRE;
1080 status = (*state_fn->fn)(ep, asoc, subtype, event_arg, &commands);
1081 DEBUG_POST;
1082
1083 error = sctp_side_effects(event_type, subtype, state,
1084 ep, asoc, event_arg, status,
1085 &commands, gfp);
1086 DEBUG_POST_SFX;
1087
1088 return error;
1089 }
1090
1091 #undef DEBUG_PRE
1092 #undef DEBUG_POST
1093
1094 /*****************************************************************
1095 * This the master state function side effect processing function.
1096 *****************************************************************/
1097 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
1098 sctp_state_t state,
1099 struct sctp_endpoint *ep,
1100 struct sctp_association *asoc,
1101 void *event_arg,
1102 sctp_disposition_t status,
1103 sctp_cmd_seq_t *commands,
1104 gfp_t gfp)
1105 {
1106 int error;
1107
1108 /* FIXME - Most of the dispositions left today would be categorized
1109 * as "exceptional" dispositions. For those dispositions, it
1110 * may not be proper to run through any of the commands at all.
1111 * For example, the command interpreter might be run only with
1112 * disposition SCTP_DISPOSITION_CONSUME.
1113 */
1114 if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state,
1115 ep, asoc,
1116 event_arg, status,
1117 commands, gfp)))
1118 goto bail;
1119
1120 switch (status) {
1121 case SCTP_DISPOSITION_DISCARD:
1122 SCTP_DEBUG_PRINTK("Ignored sctp protocol event - state %d, "
1123 "event_type %d, event_id %d\n",
1124 state, event_type, subtype.chunk);
1125 break;
1126
1127 case SCTP_DISPOSITION_NOMEM:
1128 /* We ran out of memory, so we need to discard this
1129 * packet.
1130 */
1131 /* BUG--we should now recover some memory, probably by
1132 * reneging...
1133 */
1134 error = -ENOMEM;
1135 break;
1136
1137 case SCTP_DISPOSITION_DELETE_TCB:
1138 /* This should now be a command. */
1139 break;
1140
1141 case SCTP_DISPOSITION_CONSUME:
1142 case SCTP_DISPOSITION_ABORT:
1143 /*
1144 * We should no longer have much work to do here as the
1145 * real work has been done as explicit commands above.
1146 */
1147 break;
1148
1149 case SCTP_DISPOSITION_VIOLATION:
1150 if (net_ratelimit())
1151 pr_err("protocol violation state %d chunkid %d\n",
1152 state, subtype.chunk);
1153 break;
1154
1155 case SCTP_DISPOSITION_NOT_IMPL:
1156 pr_warn("unimplemented feature in state %d, event_type %d, event_id %d\n",
1157 state, event_type, subtype.chunk);
1158 break;
1159
1160 case SCTP_DISPOSITION_BUG:
1161 pr_err("bug in state %d, event_type %d, event_id %d\n",
1162 state, event_type, subtype.chunk);
1163 BUG();
1164 break;
1165
1166 default:
1167 pr_err("impossible disposition %d in state %d, event_type %d, event_id %d\n",
1168 status, state, event_type, subtype.chunk);
1169 BUG();
1170 break;
1171 }
1172
1173 bail:
1174 return error;
1175 }
1176
1177 /********************************************************************
1178 * 2nd Level Abstractions
1179 ********************************************************************/
1180
1181 /* This is the side-effect interpreter. */
1182 static int sctp_cmd_interpreter(sctp_event_t event_type,
1183 sctp_subtype_t subtype,
1184 sctp_state_t state,
1185 struct sctp_endpoint *ep,
1186 struct sctp_association *asoc,
1187 void *event_arg,
1188 sctp_disposition_t status,
1189 sctp_cmd_seq_t *commands,
1190 gfp_t gfp)
1191 {
1192 int error = 0;
1193 int force;
1194 sctp_cmd_t *cmd;
1195 struct sctp_chunk *new_obj;
1196 struct sctp_chunk *chunk = NULL;
1197 struct sctp_packet *packet;
1198 struct timer_list *timer;
1199 unsigned long timeout;
1200 struct sctp_transport *t;
1201 struct sctp_sackhdr sackh;
1202 int local_cork = 0;
1203
1204 if (SCTP_EVENT_T_TIMEOUT != event_type)
1205 chunk = (struct sctp_chunk *) event_arg;
1206
1207 /* Note: This whole file is a huge candidate for rework.
1208 * For example, each command could either have its own handler, so
1209 * the loop would look like:
1210 * while (cmds)
1211 * cmd->handle(x, y, z)
1212 * --jgrimm
1213 */
1214 while (NULL != (cmd = sctp_next_cmd(commands))) {
1215 switch (cmd->verb) {
1216 case SCTP_CMD_NOP:
1217 /* Do nothing. */
1218 break;
1219
1220 case SCTP_CMD_NEW_ASOC:
1221 /* Register a new association. */
1222 if (local_cork) {
1223 sctp_outq_uncork(&asoc->outqueue);
1224 local_cork = 0;
1225 }
1226 asoc = cmd->obj.ptr;
1227 /* Register with the endpoint. */
1228 sctp_endpoint_add_asoc(ep, asoc);
1229 sctp_hash_established(asoc);
1230 break;
1231
1232 case SCTP_CMD_UPDATE_ASSOC:
1233 sctp_assoc_update(asoc, cmd->obj.ptr);
1234 break;
1235
1236 case SCTP_CMD_PURGE_OUTQUEUE:
1237 sctp_outq_teardown(&asoc->outqueue);
1238 break;
1239
1240 case SCTP_CMD_DELETE_TCB:
1241 if (local_cork) {
1242 sctp_outq_uncork(&asoc->outqueue);
1243 local_cork = 0;
1244 }
1245 /* Delete the current association. */
1246 sctp_cmd_delete_tcb(commands, asoc);
1247 asoc = NULL;
1248 break;
1249
1250 case SCTP_CMD_NEW_STATE:
1251 /* Enter a new state. */
1252 sctp_cmd_new_state(commands, asoc, cmd->obj.state);
1253 break;
1254
1255 case SCTP_CMD_REPORT_TSN:
1256 /* Record the arrival of a TSN. */
1257 error = sctp_tsnmap_mark(&asoc->peer.tsn_map,
1258 cmd->obj.u32);
1259 break;
1260
1261 case SCTP_CMD_REPORT_FWDTSN:
1262 /* Move the Cumulattive TSN Ack ahead. */
1263 sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32);
1264
1265 /* purge the fragmentation queue */
1266 sctp_ulpq_reasm_flushtsn(&asoc->ulpq, cmd->obj.u32);
1267
1268 /* Abort any in progress partial delivery. */
1269 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
1270 break;
1271
1272 case SCTP_CMD_PROCESS_FWDTSN:
1273 sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.ptr);
1274 break;
1275
1276 case SCTP_CMD_GEN_SACK:
1277 /* Generate a Selective ACK.
1278 * The argument tells us whether to just count
1279 * the packet and MAYBE generate a SACK, or
1280 * force a SACK out.
1281 */
1282 force = cmd->obj.i32;
1283 error = sctp_gen_sack(asoc, force, commands);
1284 break;
1285
1286 case SCTP_CMD_PROCESS_SACK:
1287 /* Process an inbound SACK. */
1288 error = sctp_cmd_process_sack(commands, asoc,
1289 cmd->obj.ptr);
1290 break;
1291
1292 case SCTP_CMD_GEN_INIT_ACK:
1293 /* Generate an INIT ACK chunk. */
1294 new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC,
1295 0);
1296 if (!new_obj)
1297 goto nomem;
1298
1299 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1300 SCTP_CHUNK(new_obj));
1301 break;
1302
1303 case SCTP_CMD_PEER_INIT:
1304 /* Process a unified INIT from the peer.
1305 * Note: Only used during INIT-ACK processing. If
1306 * there is an error just return to the outter
1307 * layer which will bail.
1308 */
1309 error = sctp_cmd_process_init(commands, asoc, chunk,
1310 cmd->obj.ptr, gfp);
1311 break;
1312
1313 case SCTP_CMD_GEN_COOKIE_ECHO:
1314 /* Generate a COOKIE ECHO chunk. */
1315 new_obj = sctp_make_cookie_echo(asoc, chunk);
1316 if (!new_obj) {
1317 if (cmd->obj.ptr)
1318 sctp_chunk_free(cmd->obj.ptr);
1319 goto nomem;
1320 }
1321 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1322 SCTP_CHUNK(new_obj));
1323
1324 /* If there is an ERROR chunk to be sent along with
1325 * the COOKIE_ECHO, send it, too.
1326 */
1327 if (cmd->obj.ptr)
1328 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1329 SCTP_CHUNK(cmd->obj.ptr));
1330
1331 if (new_obj->transport) {
1332 new_obj->transport->init_sent_count++;
1333 asoc->init_last_sent_to = new_obj->transport;
1334 }
1335
1336 /* FIXME - Eventually come up with a cleaner way to
1337 * enabling COOKIE-ECHO + DATA bundling during
1338 * multihoming stale cookie scenarios, the following
1339 * command plays with asoc->peer.retran_path to
1340 * avoid the problem of sending the COOKIE-ECHO and
1341 * DATA in different paths, which could result
1342 * in the association being ABORTed if the DATA chunk
1343 * is processed first by the server. Checking the
1344 * init error counter simply causes this command
1345 * to be executed only during failed attempts of
1346 * association establishment.
1347 */
1348 if ((asoc->peer.retran_path !=
1349 asoc->peer.primary_path) &&
1350 (asoc->init_err_counter > 0)) {
1351 sctp_add_cmd_sf(commands,
1352 SCTP_CMD_FORCE_PRIM_RETRAN,
1353 SCTP_NULL());
1354 }
1355
1356 break;
1357
1358 case SCTP_CMD_GEN_SHUTDOWN:
1359 /* Generate SHUTDOWN when in SHUTDOWN_SENT state.
1360 * Reset error counts.
1361 */
1362 asoc->overall_error_count = 0;
1363
1364 /* Generate a SHUTDOWN chunk. */
1365 new_obj = sctp_make_shutdown(asoc, chunk);
1366 if (!new_obj)
1367 goto nomem;
1368 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1369 SCTP_CHUNK(new_obj));
1370 break;
1371
1372 case SCTP_CMD_CHUNK_ULP:
1373 /* Send a chunk to the sockets layer. */
1374 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1375 "chunk_up:", cmd->obj.ptr,
1376 "ulpq:", &asoc->ulpq);
1377 sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.ptr,
1378 GFP_ATOMIC);
1379 break;
1380
1381 case SCTP_CMD_EVENT_ULP:
1382 /* Send a notification to the sockets layer. */
1383 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1384 "event_up:",cmd->obj.ptr,
1385 "ulpq:",&asoc->ulpq);
1386 sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ptr);
1387 break;
1388
1389 case SCTP_CMD_REPLY:
1390 /* If an caller has not already corked, do cork. */
1391 if (!asoc->outqueue.cork) {
1392 sctp_outq_cork(&asoc->outqueue);
1393 local_cork = 1;
1394 }
1395 /* Send a chunk to our peer. */
1396 error = sctp_outq_tail(&asoc->outqueue, cmd->obj.ptr);
1397 break;
1398
1399 case SCTP_CMD_SEND_PKT:
1400 /* Send a full packet to our peer. */
1401 packet = cmd->obj.ptr;
1402 sctp_packet_transmit(packet);
1403 sctp_ootb_pkt_free(packet);
1404 break;
1405
1406 case SCTP_CMD_T1_RETRAN:
1407 /* Mark a transport for retransmission. */
1408 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1409 SCTP_RTXR_T1_RTX);
1410 break;
1411
1412 case SCTP_CMD_RETRAN:
1413 /* Mark a transport for retransmission. */
1414 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1415 SCTP_RTXR_T3_RTX);
1416 break;
1417
1418 case SCTP_CMD_TRANSMIT:
1419 /* Kick start transmission. */
1420 error = sctp_outq_uncork(&asoc->outqueue);
1421 local_cork = 0;
1422 break;
1423
1424 case SCTP_CMD_ECN_CE:
1425 /* Do delayed CE processing. */
1426 sctp_do_ecn_ce_work(asoc, cmd->obj.u32);
1427 break;
1428
1429 case SCTP_CMD_ECN_ECNE:
1430 /* Do delayed ECNE processing. */
1431 new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32,
1432 chunk);
1433 if (new_obj)
1434 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1435 SCTP_CHUNK(new_obj));
1436 break;
1437
1438 case SCTP_CMD_ECN_CWR:
1439 /* Do delayed CWR processing. */
1440 sctp_do_ecn_cwr_work(asoc, cmd->obj.u32);
1441 break;
1442
1443 case SCTP_CMD_SETUP_T2:
1444 sctp_cmd_setup_t2(commands, asoc, cmd->obj.ptr);
1445 break;
1446
1447 case SCTP_CMD_TIMER_START:
1448 timer = &asoc->timers[cmd->obj.to];
1449 timeout = asoc->timeouts[cmd->obj.to];
1450 BUG_ON(!timeout);
1451
1452 timer->expires = jiffies + timeout;
1453 sctp_association_hold(asoc);
1454 add_timer(timer);
1455 break;
1456
1457 case SCTP_CMD_TIMER_RESTART:
1458 timer = &asoc->timers[cmd->obj.to];
1459 timeout = asoc->timeouts[cmd->obj.to];
1460 if (!mod_timer(timer, jiffies + timeout))
1461 sctp_association_hold(asoc);
1462 break;
1463
1464 case SCTP_CMD_TIMER_STOP:
1465 timer = &asoc->timers[cmd->obj.to];
1466 if (timer_pending(timer) && del_timer(timer))
1467 sctp_association_put(asoc);
1468 break;
1469
1470 case SCTP_CMD_INIT_CHOOSE_TRANSPORT:
1471 chunk = cmd->obj.ptr;
1472 t = sctp_assoc_choose_alter_transport(asoc,
1473 asoc->init_last_sent_to);
1474 asoc->init_last_sent_to = t;
1475 chunk->transport = t;
1476 t->init_sent_count++;
1477 /* Set the new transport as primary */
1478 sctp_assoc_set_primary(asoc, t);
1479 break;
1480
1481 case SCTP_CMD_INIT_RESTART:
1482 /* Do the needed accounting and updates
1483 * associated with restarting an initialization
1484 * timer. Only multiply the timeout by two if
1485 * all transports have been tried at the current
1486 * timeout.
1487 */
1488 sctp_cmd_t1_timer_update(asoc,
1489 SCTP_EVENT_TIMEOUT_T1_INIT,
1490 "INIT");
1491
1492 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
1493 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
1494 break;
1495
1496 case SCTP_CMD_COOKIEECHO_RESTART:
1497 /* Do the needed accounting and updates
1498 * associated with restarting an initialization
1499 * timer. Only multiply the timeout by two if
1500 * all transports have been tried at the current
1501 * timeout.
1502 */
1503 sctp_cmd_t1_timer_update(asoc,
1504 SCTP_EVENT_TIMEOUT_T1_COOKIE,
1505 "COOKIE");
1506
1507 /* If we've sent any data bundled with
1508 * COOKIE-ECHO we need to resend.
1509 */
1510 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1511 transports) {
1512 sctp_retransmit_mark(&asoc->outqueue, t,
1513 SCTP_RTXR_T1_RTX);
1514 }
1515
1516 sctp_add_cmd_sf(commands,
1517 SCTP_CMD_TIMER_RESTART,
1518 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
1519 break;
1520
1521 case SCTP_CMD_INIT_FAILED:
1522 sctp_cmd_init_failed(commands, asoc, cmd->obj.err);
1523 break;
1524
1525 case SCTP_CMD_ASSOC_FAILED:
1526 sctp_cmd_assoc_failed(commands, asoc, event_type,
1527 subtype, chunk, cmd->obj.err);
1528 break;
1529
1530 case SCTP_CMD_INIT_COUNTER_INC:
1531 asoc->init_err_counter++;
1532 break;
1533
1534 case SCTP_CMD_INIT_COUNTER_RESET:
1535 asoc->init_err_counter = 0;
1536 asoc->init_cycle = 0;
1537 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1538 transports) {
1539 t->init_sent_count = 0;
1540 }
1541 break;
1542
1543 case SCTP_CMD_REPORT_DUP:
1544 sctp_tsnmap_mark_dup(&asoc->peer.tsn_map,
1545 cmd->obj.u32);
1546 break;
1547
1548 case SCTP_CMD_REPORT_BAD_TAG:
1549 SCTP_DEBUG_PRINTK("vtag mismatch!\n");
1550 break;
1551
1552 case SCTP_CMD_STRIKE:
1553 /* Mark one strike against a transport. */
1554 sctp_do_8_2_transport_strike(asoc, cmd->obj.transport,
1555 0);
1556 break;
1557
1558 case SCTP_CMD_TRANSPORT_IDLE:
1559 t = cmd->obj.transport;
1560 sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE);
1561 break;
1562
1563 case SCTP_CMD_TRANSPORT_HB_SENT:
1564 t = cmd->obj.transport;
1565 sctp_do_8_2_transport_strike(asoc, t, 1);
1566 t->hb_sent = 1;
1567 break;
1568
1569 case SCTP_CMD_TRANSPORT_ON:
1570 t = cmd->obj.transport;
1571 sctp_cmd_transport_on(commands, asoc, t, chunk);
1572 break;
1573
1574 case SCTP_CMD_HB_TIMERS_START:
1575 sctp_cmd_hb_timers_start(commands, asoc);
1576 break;
1577
1578 case SCTP_CMD_HB_TIMER_UPDATE:
1579 t = cmd->obj.transport;
1580 sctp_cmd_hb_timer_update(commands, t);
1581 break;
1582
1583 case SCTP_CMD_HB_TIMERS_STOP:
1584 sctp_cmd_hb_timers_stop(commands, asoc);
1585 break;
1586
1587 case SCTP_CMD_REPORT_ERROR:
1588 error = cmd->obj.error;
1589 break;
1590
1591 case SCTP_CMD_PROCESS_CTSN:
1592 /* Dummy up a SACK for processing. */
1593 sackh.cum_tsn_ack = cmd->obj.be32;
1594 sackh.a_rwnd = asoc->peer.rwnd +
1595 asoc->outqueue.outstanding_bytes;
1596 sackh.num_gap_ack_blocks = 0;
1597 sackh.num_dup_tsns = 0;
1598 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK,
1599 SCTP_SACKH(&sackh));
1600 break;
1601
1602 case SCTP_CMD_DISCARD_PACKET:
1603 /* We need to discard the whole packet.
1604 * Uncork the queue since there might be
1605 * responses pending
1606 */
1607 chunk->pdiscard = 1;
1608 if (asoc) {
1609 sctp_outq_uncork(&asoc->outqueue);
1610 local_cork = 0;
1611 }
1612 break;
1613
1614 case SCTP_CMD_RTO_PENDING:
1615 t = cmd->obj.transport;
1616 t->rto_pending = 1;
1617 break;
1618
1619 case SCTP_CMD_PART_DELIVER:
1620 sctp_ulpq_partial_delivery(&asoc->ulpq, cmd->obj.ptr,
1621 GFP_ATOMIC);
1622 break;
1623
1624 case SCTP_CMD_RENEGE:
1625 sctp_ulpq_renege(&asoc->ulpq, cmd->obj.ptr,
1626 GFP_ATOMIC);
1627 break;
1628
1629 case SCTP_CMD_SETUP_T4:
1630 sctp_cmd_setup_t4(commands, asoc, cmd->obj.ptr);
1631 break;
1632
1633 case SCTP_CMD_PROCESS_OPERR:
1634 sctp_cmd_process_operr(commands, asoc, chunk);
1635 break;
1636 case SCTP_CMD_CLEAR_INIT_TAG:
1637 asoc->peer.i.init_tag = 0;
1638 break;
1639 case SCTP_CMD_DEL_NON_PRIMARY:
1640 sctp_cmd_del_non_primary(asoc);
1641 break;
1642 case SCTP_CMD_T3_RTX_TIMERS_STOP:
1643 sctp_cmd_t3_rtx_timers_stop(commands, asoc);
1644 break;
1645 case SCTP_CMD_FORCE_PRIM_RETRAN:
1646 t = asoc->peer.retran_path;
1647 asoc->peer.retran_path = asoc->peer.primary_path;
1648 error = sctp_outq_uncork(&asoc->outqueue);
1649 local_cork = 0;
1650 asoc->peer.retran_path = t;
1651 break;
1652 case SCTP_CMD_SET_SK_ERR:
1653 sctp_cmd_set_sk_err(asoc, cmd->obj.error);
1654 break;
1655 case SCTP_CMD_ASSOC_CHANGE:
1656 sctp_cmd_assoc_change(commands, asoc,
1657 cmd->obj.u8);
1658 break;
1659 case SCTP_CMD_ADAPTATION_IND:
1660 sctp_cmd_adaptation_ind(commands, asoc);
1661 break;
1662
1663 case SCTP_CMD_ASSOC_SHKEY:
1664 error = sctp_auth_asoc_init_active_key(asoc,
1665 GFP_ATOMIC);
1666 break;
1667 case SCTP_CMD_UPDATE_INITTAG:
1668 asoc->peer.i.init_tag = cmd->obj.u32;
1669 break;
1670 case SCTP_CMD_SEND_MSG:
1671 if (!asoc->outqueue.cork) {
1672 sctp_outq_cork(&asoc->outqueue);
1673 local_cork = 1;
1674 }
1675 error = sctp_cmd_send_msg(asoc, cmd->obj.msg);
1676 break;
1677 case SCTP_CMD_SEND_NEXT_ASCONF:
1678 sctp_cmd_send_asconf(asoc);
1679 break;
1680 default:
1681 pr_warn("Impossible command: %u, %p\n",
1682 cmd->verb, cmd->obj.ptr);
1683 break;
1684 }
1685
1686 if (error)
1687 break;
1688 }
1689
1690 out:
1691 /* If this is in response to a received chunk, wait until
1692 * we are done with the packet to open the queue so that we don't
1693 * send multiple packets in response to a single request.
1694 */
1695 if (asoc && SCTP_EVENT_T_CHUNK == event_type && chunk) {
1696 if (chunk->end_of_packet || chunk->singleton)
1697 error = sctp_outq_uncork(&asoc->outqueue);
1698 } else if (local_cork)
1699 error = sctp_outq_uncork(&asoc->outqueue);
1700 return error;
1701 nomem:
1702 error = -ENOMEM;
1703 goto out;
1704 }
1705