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Merge branch 'sched/core'
[linux-2.6/x86.git] / net / sctp / sm_sideeffect.c
blob534c2e5feb054c933cbd0dcf46a0cb66386646dd
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 * Additionally, 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, sctp_source(chunk), peer_init, gfp))
599 error = -ENOMEM;
600 else
601 error = 0;
602
603 return error;
604 }
605
606 /* Helper function to break out starting up of heartbeat timers. */
607 static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds,
608 struct sctp_association *asoc)
609 {
610 struct sctp_transport *t;
611
612 /* Start a heartbeat timer for each transport on the association.
613 * hold a reference on the transport to make sure none of
614 * the needed data structures go away.
615 */
616 list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) {
617
618 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
619 sctp_transport_hold(t);
620 }
621 }
622
623 static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds,
624 struct sctp_association *asoc)
625 {
626 struct sctp_transport *t;
627
628 /* Stop all heartbeat timers. */
629
630 list_for_each_entry(t, &asoc->peer.transport_addr_list,
631 transports) {
632 if (del_timer(&t->hb_timer))
633 sctp_transport_put(t);
634 }
635 }
636
637 /* Helper function to stop any pending T3-RTX timers */
638 static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds,
639 struct sctp_association *asoc)
640 {
641 struct sctp_transport *t;
642
643 list_for_each_entry(t, &asoc->peer.transport_addr_list,
644 transports) {
645 if (timer_pending(&t->T3_rtx_timer) &&
646 del_timer(&t->T3_rtx_timer)) {
647 sctp_transport_put(t);
648 }
649 }
650 }
651
652
653 /* Helper function to update the heartbeat timer. */
654 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds,
655 struct sctp_transport *t)
656 {
657 /* Update the heartbeat timer. */
658 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
659 sctp_transport_hold(t);
660 }
661
662 /* Helper function to handle the reception of an HEARTBEAT ACK. */
663 static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds,
664 struct sctp_association *asoc,
665 struct sctp_transport *t,
666 struct sctp_chunk *chunk)
667 {
668 sctp_sender_hb_info_t *hbinfo;
669
670 /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the
671 * HEARTBEAT should clear the error counter of the destination
672 * transport address to which the HEARTBEAT was sent.
673 * The association's overall error count is also cleared.
674 */
675 t->error_count = 0;
676 t->asoc->overall_error_count = 0;
677
678 /* Clear the hb_sent flag to signal that we had a good
679 * acknowledgement.
680 */
681 t->hb_sent = 0;
682
683 /* Mark the destination transport address as active if it is not so
684 * marked.
685 */
686 if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED))
687 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
688 SCTP_HEARTBEAT_SUCCESS);
689
690 /* The receiver of the HEARTBEAT ACK should also perform an
691 * RTT measurement for that destination transport address
692 * using the time value carried in the HEARTBEAT ACK chunk.
693 * If the transport's rto_pending variable has been cleared,
694 * it was most likely due to a retransmit. However, we want
695 * to re-enable it to properly update the rto.
696 */
697 if (t->rto_pending == 0)
698 t->rto_pending = 1;
699
700 hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data;
701 sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at));
702
703 /* Update the heartbeat timer. */
704 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
705 sctp_transport_hold(t);
706 }
707
708
709 /* Helper function to process the process SACK command. */
710 static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds,
711 struct sctp_association *asoc,
712 struct sctp_sackhdr *sackh)
713 {
714 int err = 0;
715
716 if (sctp_outq_sack(&asoc->outqueue, sackh)) {
717 /* There are no more TSNs awaiting SACK. */
718 err = sctp_do_sm(SCTP_EVENT_T_OTHER,
719 SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN),
720 asoc->state, asoc->ep, asoc, NULL,
721 GFP_ATOMIC);
722 }
723
724 return err;
725 }
726
727 /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set
728 * the transport for a shutdown chunk.
729 */
730 static void sctp_cmd_setup_t2(sctp_cmd_seq_t *cmds,
731 struct sctp_association *asoc,
732 struct sctp_chunk *chunk)
733 {
734 struct sctp_transport *t;
735
736 if (chunk->transport)
737 t = chunk->transport;
738 else {
739 t = sctp_assoc_choose_alter_transport(asoc,
740 asoc->shutdown_last_sent_to);
741 chunk->transport = t;
742 }
743 asoc->shutdown_last_sent_to = t;
744 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto;
745 }
746
747 /* Helper function to change the state of an association. */
748 static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds,
749 struct sctp_association *asoc,
750 sctp_state_t state)
751 {
752 struct sock *sk = asoc->base.sk;
753
754 asoc->state = state;
755
756 SCTP_DEBUG_PRINTK("sctp_cmd_new_state: asoc %p[%s]\n",
757 asoc, sctp_state_tbl[state]);
758
759 if (sctp_style(sk, TCP)) {
760 /* Change the sk->sk_state of a TCP-style socket that has
761 * successfully completed a connect() call.
762 */
763 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED))
764 sk->sk_state = SCTP_SS_ESTABLISHED;
765
766 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */
767 if (sctp_state(asoc, SHUTDOWN_RECEIVED) &&
768 sctp_sstate(sk, ESTABLISHED))
769 sk->sk_shutdown |= RCV_SHUTDOWN;
770 }
771
772 if (sctp_state(asoc, COOKIE_WAIT)) {
773 /* Reset init timeouts since they may have been
774 * increased due to timer expirations.
775 */
776 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
777 asoc->rto_initial;
778 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
779 asoc->rto_initial;
780 }
781
782 if (sctp_state(asoc, ESTABLISHED) ||
783 sctp_state(asoc, CLOSED) ||
784 sctp_state(asoc, SHUTDOWN_RECEIVED)) {
785 /* Wake up any processes waiting in the asoc's wait queue in
786 * sctp_wait_for_connect() or sctp_wait_for_sndbuf().
787 */
788 if (waitqueue_active(&asoc->wait))
789 wake_up_interruptible(&asoc->wait);
790
791 /* Wake up any processes waiting in the sk's sleep queue of
792 * a TCP-style or UDP-style peeled-off socket in
793 * sctp_wait_for_accept() or sctp_wait_for_packet().
794 * For a UDP-style socket, the waiters are woken up by the
795 * notifications.
796 */
797 if (!sctp_style(sk, UDP))
798 sk->sk_state_change(sk);
799 }
800 }
801
802 /* Helper function to delete an association. */
803 static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds,
804 struct sctp_association *asoc)
805 {
806 struct sock *sk = asoc->base.sk;
807
808 /* If it is a non-temporary association belonging to a TCP-style
809 * listening socket that is not closed, do not free it so that accept()
810 * can pick it up later.
811 */
812 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) &&
813 (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK))
814 return;
815
816 sctp_unhash_established(asoc);
817 sctp_association_free(asoc);
818 }
819
820 /*
821 * ADDIP Section 4.1 ASCONF Chunk Procedures
822 * A4) Start a T-4 RTO timer, using the RTO value of the selected
823 * destination address (we use active path instead of primary path just
824 * because primary path may be inactive.
825 */
826 static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds,
827 struct sctp_association *asoc,
828 struct sctp_chunk *chunk)
829 {
830 struct sctp_transport *t;
831
832 t = sctp_assoc_choose_alter_transport(asoc, chunk->transport);
833 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto;
834 chunk->transport = t;
835 }
836
837 /* Process an incoming Operation Error Chunk. */
838 static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds,
839 struct sctp_association *asoc,
840 struct sctp_chunk *chunk)
841 {
842 struct sctp_errhdr *err_hdr;
843 struct sctp_ulpevent *ev;
844
845 while (chunk->chunk_end > chunk->skb->data) {
846 err_hdr = (struct sctp_errhdr *)(chunk->skb->data);
847
848 ev = sctp_ulpevent_make_remote_error(asoc, chunk, 0,
849 GFP_ATOMIC);
850 if (!ev)
851 return;
852
853 sctp_ulpq_tail_event(&asoc->ulpq, ev);
854
855 switch (err_hdr->cause) {
856 case SCTP_ERROR_UNKNOWN_CHUNK:
857 {
858 sctp_chunkhdr_t *unk_chunk_hdr;
859
860 unk_chunk_hdr = (sctp_chunkhdr_t *)err_hdr->variable;
861 switch (unk_chunk_hdr->type) {
862 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with
863 * an ERROR chunk reporting that it did not recognized
864 * the ASCONF chunk type, the sender of the ASCONF MUST
865 * NOT send any further ASCONF chunks and MUST stop its
866 * T-4 timer.
867 */
868 case SCTP_CID_ASCONF:
869 if (asoc->peer.asconf_capable == 0)
870 break;
871
872 asoc->peer.asconf_capable = 0;
873 sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP,
874 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
875 break;
876 default:
877 break;
878 }
879 break;
880 }
881 default:
882 break;
883 }
884 }
885 }
886
887 /* Process variable FWDTSN chunk information. */
888 static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq,
889 struct sctp_chunk *chunk)
890 {
891 struct sctp_fwdtsn_skip *skip;
892 /* Walk through all the skipped SSNs */
893 sctp_walk_fwdtsn(skip, chunk) {
894 sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn));
895 }
896 }
897
898 /* Helper function to remove the association non-primary peer
899 * transports.
900 */
901 static void sctp_cmd_del_non_primary(struct sctp_association *asoc)
902 {
903 struct sctp_transport *t;
904 struct list_head *pos;
905 struct list_head *temp;
906
907 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
908 t = list_entry(pos, struct sctp_transport, transports);
909 if (!sctp_cmp_addr_exact(&t->ipaddr,
910 &asoc->peer.primary_addr)) {
911 sctp_assoc_del_peer(asoc, &t->ipaddr);
912 }
913 }
914 }
915
916 /* Helper function to set sk_err on a 1-1 style socket. */
917 static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error)
918 {
919 struct sock *sk = asoc->base.sk;
920
921 if (!sctp_style(sk, UDP))
922 sk->sk_err = error;
923 }
924
925 /* Helper function to generate an association change event */
926 static void sctp_cmd_assoc_change(sctp_cmd_seq_t *commands,
927 struct sctp_association *asoc,
928 u8 state)
929 {
930 struct sctp_ulpevent *ev;
931
932 ev = sctp_ulpevent_make_assoc_change(asoc, 0, state, 0,
933 asoc->c.sinit_num_ostreams,
934 asoc->c.sinit_max_instreams,
935 NULL, GFP_ATOMIC);
936 if (ev)
937 sctp_ulpq_tail_event(&asoc->ulpq, ev);
938 }
939
940 /* Helper function to generate an adaptation indication event */
941 static void sctp_cmd_adaptation_ind(sctp_cmd_seq_t *commands,
942 struct sctp_association *asoc)
943 {
944 struct sctp_ulpevent *ev;
945
946 ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC);
947
948 if (ev)
949 sctp_ulpq_tail_event(&asoc->ulpq, ev);
950 }
951
952
953 static void sctp_cmd_t1_timer_update(struct sctp_association *asoc,
954 sctp_event_timeout_t timer,
955 char *name)
956 {
957 struct sctp_transport *t;
958
959 t = asoc->init_last_sent_to;
960 asoc->init_err_counter++;
961
962 if (t->init_sent_count > (asoc->init_cycle + 1)) {
963 asoc->timeouts[timer] *= 2;
964 if (asoc->timeouts[timer] > asoc->max_init_timeo) {
965 asoc->timeouts[timer] = asoc->max_init_timeo;
966 }
967 asoc->init_cycle++;
968 SCTP_DEBUG_PRINTK(
969 "T1 %s Timeout adjustment"
970 " init_err_counter: %d"
971 " cycle: %d"
972 " timeout: %ld\n",
973 name,
974 asoc->init_err_counter,
975 asoc->init_cycle,
976 asoc->timeouts[timer]);
977 }
978
979 }
980
981 /* Send the whole message, chunk by chunk, to the outqueue.
982 * This way the whole message is queued up and bundling if
983 * encouraged for small fragments.
984 */
985 static int sctp_cmd_send_msg(struct sctp_association *asoc,
986 struct sctp_datamsg *msg)
987 {
988 struct sctp_chunk *chunk;
989 int error = 0;
990
991 list_for_each_entry(chunk, &msg->chunks, frag_list) {
992 error = sctp_outq_tail(&asoc->outqueue, chunk);
993 if (error)
994 break;
995 }
996
997 return error;
998 }
999
1000
1001 /* Sent the next ASCONF packet currently stored in the association.
1002 * This happens after the ASCONF_ACK was succeffully processed.
1003 */
1004 static void sctp_cmd_send_asconf(struct sctp_association *asoc)
1005 {
1006 /* Send the next asconf chunk from the addip chunk
1007 * queue.
1008 */
1009 if (!list_empty(&asoc->addip_chunk_list)) {
1010 struct list_head *entry = asoc->addip_chunk_list.next;
1011 struct sctp_chunk *asconf = list_entry(entry,
1012 struct sctp_chunk, list);
1013 list_del_init(entry);
1014
1015 /* Hold the chunk until an ASCONF_ACK is received. */
1016 sctp_chunk_hold(asconf);
1017 if (sctp_primitive_ASCONF(asoc, asconf))
1018 sctp_chunk_free(asconf);
1019 else
1020 asoc->addip_last_asconf = asconf;
1021 }
1022 }
1023
1024
1025 /* These three macros allow us to pull the debugging code out of the
1026 * main flow of sctp_do_sm() to keep attention focused on the real
1027 * functionality there.
1028 */
1029 #define DEBUG_PRE \
1030 SCTP_DEBUG_PRINTK("sctp_do_sm prefn: " \
1031 "ep %p, %s, %s, asoc %p[%s], %s\n", \
1032 ep, sctp_evttype_tbl[event_type], \
1033 (*debug_fn)(subtype), asoc, \
1034 sctp_state_tbl[state], state_fn->name)
1035
1036 #define DEBUG_POST \
1037 SCTP_DEBUG_PRINTK("sctp_do_sm postfn: " \
1038 "asoc %p, status: %s\n", \
1039 asoc, sctp_status_tbl[status])
1040
1041 #define DEBUG_POST_SFX \
1042 SCTP_DEBUG_PRINTK("sctp_do_sm post sfx: error %d, asoc %p[%s]\n", \
1043 error, asoc, \
1044 sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \
1045 sctp_assoc2id(asoc)))?asoc->state:SCTP_STATE_CLOSED])
1046
1047 /*
1048 * This is the master state machine processing function.
1049 *
1050 * If you want to understand all of lksctp, this is a
1051 * good place to start.
1052 */
1053 int sctp_do_sm(sctp_event_t event_type, sctp_subtype_t subtype,
1054 sctp_state_t state,
1055 struct sctp_endpoint *ep,
1056 struct sctp_association *asoc,
1057 void *event_arg,
1058 gfp_t gfp)
1059 {
1060 sctp_cmd_seq_t commands;
1061 const sctp_sm_table_entry_t *state_fn;
1062 sctp_disposition_t status;
1063 int error = 0;
1064 typedef const char *(printfn_t)(sctp_subtype_t);
1065
1066 static printfn_t *table[] = {
1067 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname,
1068 };
1069 printfn_t *debug_fn __attribute__ ((unused)) = table[event_type];
1070
1071 /* Look up the state function, run it, and then process the
1072 * side effects. These three steps are the heart of lksctp.
1073 */
1074 state_fn = sctp_sm_lookup_event(event_type, state, subtype);
1075
1076 sctp_init_cmd_seq(&commands);
1077
1078 DEBUG_PRE;
1079 status = (*state_fn->fn)(ep, asoc, subtype, event_arg, &commands);
1080 DEBUG_POST;
1081
1082 error = sctp_side_effects(event_type, subtype, state,
1083 ep, asoc, event_arg, status,
1084 &commands, gfp);
1085 DEBUG_POST_SFX;
1086
1087 return error;
1088 }
1089
1090 #undef DEBUG_PRE
1091 #undef DEBUG_POST
1092
1093 /*****************************************************************
1094 * This the master state function side effect processing function.
1095 *****************************************************************/
1096 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
1097 sctp_state_t state,
1098 struct sctp_endpoint *ep,
1099 struct sctp_association *asoc,
1100 void *event_arg,
1101 sctp_disposition_t status,
1102 sctp_cmd_seq_t *commands,
1103 gfp_t gfp)
1104 {
1105 int error;
1106
1107 /* FIXME - Most of the dispositions left today would be categorized
1108 * as "exceptional" dispositions. For those dispositions, it
1109 * may not be proper to run through any of the commands at all.
1110 * For example, the command interpreter might be run only with
1111 * disposition SCTP_DISPOSITION_CONSUME.
1112 */
1113 if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state,
1114 ep, asoc,
1115 event_arg, status,
1116 commands, gfp)))
1117 goto bail;
1118
1119 switch (status) {
1120 case SCTP_DISPOSITION_DISCARD:
1121 SCTP_DEBUG_PRINTK("Ignored sctp protocol event - state %d, "
1122 "event_type %d, event_id %d\n",
1123 state, event_type, subtype.chunk);
1124 break;
1125
1126 case SCTP_DISPOSITION_NOMEM:
1127 /* We ran out of memory, so we need to discard this
1128 * packet.
1129 */
1130 /* BUG--we should now recover some memory, probably by
1131 * reneging...
1132 */
1133 error = -ENOMEM;
1134 break;
1135
1136 case SCTP_DISPOSITION_DELETE_TCB:
1137 /* This should now be a command. */
1138 break;
1139
1140 case SCTP_DISPOSITION_CONSUME:
1141 case SCTP_DISPOSITION_ABORT:
1142 /*
1143 * We should no longer have much work to do here as the
1144 * real work has been done as explicit commands above.
1145 */
1146 break;
1147
1148 case SCTP_DISPOSITION_VIOLATION:
1149 if (net_ratelimit())
1150 pr_err("protocol violation state %d chunkid %d\n",
1151 state, subtype.chunk);
1152 break;
1153
1154 case SCTP_DISPOSITION_NOT_IMPL:
1155 pr_warn("unimplemented feature in state %d, event_type %d, event_id %d\n",
1156 state, event_type, subtype.chunk);
1157 break;
1158
1159 case SCTP_DISPOSITION_BUG:
1160 pr_err("bug in state %d, event_type %d, event_id %d\n",
1161 state, event_type, subtype.chunk);
1162 BUG();
1163 break;
1164
1165 default:
1166 pr_err("impossible disposition %d in state %d, event_type %d, event_id %d\n",
1167 status, state, event_type, subtype.chunk);
1168 BUG();
1169 break;
1170 }
1171
1172 bail:
1173 return error;
1174 }
1175
1176 /********************************************************************
1177 * 2nd Level Abstractions
1178 ********************************************************************/
1179
1180 /* This is the side-effect interpreter. */
1181 static int sctp_cmd_interpreter(sctp_event_t event_type,
1182 sctp_subtype_t subtype,
1183 sctp_state_t state,
1184 struct sctp_endpoint *ep,
1185 struct sctp_association *asoc,
1186 void *event_arg,
1187 sctp_disposition_t status,
1188 sctp_cmd_seq_t *commands,
1189 gfp_t gfp)
1190 {
1191 int error = 0;
1192 int force;
1193 sctp_cmd_t *cmd;
1194 struct sctp_chunk *new_obj;
1195 struct sctp_chunk *chunk = NULL;
1196 struct sctp_packet *packet;
1197 struct timer_list *timer;
1198 unsigned long timeout;
1199 struct sctp_transport *t;
1200 struct sctp_sackhdr sackh;
1201 int local_cork = 0;
1202
1203 if (SCTP_EVENT_T_TIMEOUT != event_type)
1204 chunk = (struct sctp_chunk *) event_arg;
1205
1206 /* Note: This whole file is a huge candidate for rework.
1207 * For example, each command could either have its own handler, so
1208 * the loop would look like:
1209 * while (cmds)
1210 * cmd->handle(x, y, z)
1211 * --jgrimm
1212 */
1213 while (NULL != (cmd = sctp_next_cmd(commands))) {
1214 switch (cmd->verb) {
1215 case SCTP_CMD_NOP:
1216 /* Do nothing. */
1217 break;
1218
1219 case SCTP_CMD_NEW_ASOC:
1220 /* Register a new association. */
1221 if (local_cork) {
1222 sctp_outq_uncork(&asoc->outqueue);
1223 local_cork = 0;
1224 }
1225 asoc = cmd->obj.ptr;
1226 /* Register with the endpoint. */
1227 sctp_endpoint_add_asoc(ep, asoc);
1228 sctp_hash_established(asoc);
1229 break;
1230
1231 case SCTP_CMD_UPDATE_ASSOC:
1232 sctp_assoc_update(asoc, cmd->obj.ptr);
1233 break;
1234
1235 case SCTP_CMD_PURGE_OUTQUEUE:
1236 sctp_outq_teardown(&asoc->outqueue);
1237 break;
1238
1239 case SCTP_CMD_DELETE_TCB:
1240 if (local_cork) {
1241 sctp_outq_uncork(&asoc->outqueue);
1242 local_cork = 0;
1243 }
1244 /* Delete the current association. */
1245 sctp_cmd_delete_tcb(commands, asoc);
1246 asoc = NULL;
1247 break;
1248
1249 case SCTP_CMD_NEW_STATE:
1250 /* Enter a new state. */
1251 sctp_cmd_new_state(commands, asoc, cmd->obj.state);
1252 break;
1253
1254 case SCTP_CMD_REPORT_TSN:
1255 /* Record the arrival of a TSN. */
1256 error = sctp_tsnmap_mark(&asoc->peer.tsn_map,
1257 cmd->obj.u32);
1258 break;
1259
1260 case SCTP_CMD_REPORT_FWDTSN:
1261 /* Move the Cumulattive TSN Ack ahead. */
1262 sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32);
1263
1264 /* purge the fragmentation queue */
1265 sctp_ulpq_reasm_flushtsn(&asoc->ulpq, cmd->obj.u32);
1266
1267 /* Abort any in progress partial delivery. */
1268 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
1269 break;
1270
1271 case SCTP_CMD_PROCESS_FWDTSN:
1272 sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.ptr);
1273 break;
1274
1275 case SCTP_CMD_GEN_SACK:
1276 /* Generate a Selective ACK.
1277 * The argument tells us whether to just count
1278 * the packet and MAYBE generate a SACK, or
1279 * force a SACK out.
1280 */
1281 force = cmd->obj.i32;
1282 error = sctp_gen_sack(asoc, force, commands);
1283 break;
1284
1285 case SCTP_CMD_PROCESS_SACK:
1286 /* Process an inbound SACK. */
1287 error = sctp_cmd_process_sack(commands, asoc,
1288 cmd->obj.ptr);
1289 break;
1290
1291 case SCTP_CMD_GEN_INIT_ACK:
1292 /* Generate an INIT ACK chunk. */
1293 new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC,
1294 0);
1295 if (!new_obj)
1296 goto nomem;
1297
1298 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1299 SCTP_CHUNK(new_obj));
1300 break;
1301
1302 case SCTP_CMD_PEER_INIT:
1303 /* Process a unified INIT from the peer.
1304 * Note: Only used during INIT-ACK processing. If
1305 * there is an error just return to the outter
1306 * layer which will bail.
1307 */
1308 error = sctp_cmd_process_init(commands, asoc, chunk,
1309 cmd->obj.ptr, gfp);
1310 break;
1311
1312 case SCTP_CMD_GEN_COOKIE_ECHO:
1313 /* Generate a COOKIE ECHO chunk. */
1314 new_obj = sctp_make_cookie_echo(asoc, chunk);
1315 if (!new_obj) {
1316 if (cmd->obj.ptr)
1317 sctp_chunk_free(cmd->obj.ptr);
1318 goto nomem;
1319 }
1320 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1321 SCTP_CHUNK(new_obj));
1322
1323 /* If there is an ERROR chunk to be sent along with
1324 * the COOKIE_ECHO, send it, too.
1325 */
1326 if (cmd->obj.ptr)
1327 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1328 SCTP_CHUNK(cmd->obj.ptr));
1329
1330 if (new_obj->transport) {
1331 new_obj->transport->init_sent_count++;
1332 asoc->init_last_sent_to = new_obj->transport;
1333 }
1334
1335 /* FIXME - Eventually come up with a cleaner way to
1336 * enabling COOKIE-ECHO + DATA bundling during
1337 * multihoming stale cookie scenarios, the following
1338 * command plays with asoc->peer.retran_path to
1339 * avoid the problem of sending the COOKIE-ECHO and
1340 * DATA in different paths, which could result
1341 * in the association being ABORTed if the DATA chunk
1342 * is processed first by the server. Checking the
1343 * init error counter simply causes this command
1344 * to be executed only during failed attempts of
1345 * association establishment.
1346 */
1347 if ((asoc->peer.retran_path !=
1348 asoc->peer.primary_path) &&
1349 (asoc->init_err_counter > 0)) {
1350 sctp_add_cmd_sf(commands,
1351 SCTP_CMD_FORCE_PRIM_RETRAN,
1352 SCTP_NULL());
1353 }
1354
1355 break;
1356
1357 case SCTP_CMD_GEN_SHUTDOWN:
1358 /* Generate SHUTDOWN when in SHUTDOWN_SENT state.
1359 * Reset error counts.
1360 */
1361 asoc->overall_error_count = 0;
1362
1363 /* Generate a SHUTDOWN chunk. */
1364 new_obj = sctp_make_shutdown(asoc, chunk);
1365 if (!new_obj)
1366 goto nomem;
1367 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1368 SCTP_CHUNK(new_obj));
1369 break;
1370
1371 case SCTP_CMD_CHUNK_ULP:
1372 /* Send a chunk to the sockets layer. */
1373 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1374 "chunk_up:", cmd->obj.ptr,
1375 "ulpq:", &asoc->ulpq);
1376 sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.ptr,
1377 GFP_ATOMIC);
1378 break;
1379
1380 case SCTP_CMD_EVENT_ULP:
1381 /* Send a notification to the sockets layer. */
1382 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1383 "event_up:",cmd->obj.ptr,
1384 "ulpq:",&asoc->ulpq);
1385 sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ptr);
1386 break;
1387
1388 case SCTP_CMD_REPLY:
1389 /* If an caller has not already corked, do cork. */
1390 if (!asoc->outqueue.cork) {
1391 sctp_outq_cork(&asoc->outqueue);
1392 local_cork = 1;
1393 }
1394 /* Send a chunk to our peer. */
1395 error = sctp_outq_tail(&asoc->outqueue, cmd->obj.ptr);
1396 break;
1397
1398 case SCTP_CMD_SEND_PKT:
1399 /* Send a full packet to our peer. */
1400 packet = cmd->obj.ptr;
1401 sctp_packet_transmit(packet);
1402 sctp_ootb_pkt_free(packet);
1403 break;
1404
1405 case SCTP_CMD_T1_RETRAN:
1406 /* Mark a transport for retransmission. */
1407 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1408 SCTP_RTXR_T1_RTX);
1409 break;
1410
1411 case SCTP_CMD_RETRAN:
1412 /* Mark a transport for retransmission. */
1413 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1414 SCTP_RTXR_T3_RTX);
1415 break;
1416
1417 case SCTP_CMD_ECN_CE:
1418 /* Do delayed CE processing. */
1419 sctp_do_ecn_ce_work(asoc, cmd->obj.u32);
1420 break;
1421
1422 case SCTP_CMD_ECN_ECNE:
1423 /* Do delayed ECNE processing. */
1424 new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32,
1425 chunk);
1426 if (new_obj)
1427 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1428 SCTP_CHUNK(new_obj));
1429 break;
1430
1431 case SCTP_CMD_ECN_CWR:
1432 /* Do delayed CWR processing. */
1433 sctp_do_ecn_cwr_work(asoc, cmd->obj.u32);
1434 break;
1435
1436 case SCTP_CMD_SETUP_T2:
1437 sctp_cmd_setup_t2(commands, asoc, cmd->obj.ptr);
1438 break;
1439
1440 case SCTP_CMD_TIMER_START:
1441 timer = &asoc->timers[cmd->obj.to];
1442 timeout = asoc->timeouts[cmd->obj.to];
1443 BUG_ON(!timeout);
1444
1445 timer->expires = jiffies + timeout;
1446 sctp_association_hold(asoc);
1447 add_timer(timer);
1448 break;
1449
1450 case SCTP_CMD_TIMER_RESTART:
1451 timer = &asoc->timers[cmd->obj.to];
1452 timeout = asoc->timeouts[cmd->obj.to];
1453 if (!mod_timer(timer, jiffies + timeout))
1454 sctp_association_hold(asoc);
1455 break;
1456
1457 case SCTP_CMD_TIMER_STOP:
1458 timer = &asoc->timers[cmd->obj.to];
1459 if (timer_pending(timer) && del_timer(timer))
1460 sctp_association_put(asoc);
1461 break;
1462
1463 case SCTP_CMD_INIT_CHOOSE_TRANSPORT:
1464 chunk = cmd->obj.ptr;
1465 t = sctp_assoc_choose_alter_transport(asoc,
1466 asoc->init_last_sent_to);
1467 asoc->init_last_sent_to = t;
1468 chunk->transport = t;
1469 t->init_sent_count++;
1470 /* Set the new transport as primary */
1471 sctp_assoc_set_primary(asoc, t);
1472 break;
1473
1474 case SCTP_CMD_INIT_RESTART:
1475 /* Do the needed accounting and updates
1476 * associated with restarting an initialization
1477 * timer. Only multiply the timeout by two if
1478 * all transports have been tried at the current
1479 * timeout.
1480 */
1481 sctp_cmd_t1_timer_update(asoc,
1482 SCTP_EVENT_TIMEOUT_T1_INIT,
1483 "INIT");
1484
1485 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
1486 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
1487 break;
1488
1489 case SCTP_CMD_COOKIEECHO_RESTART:
1490 /* Do the needed accounting and updates
1491 * associated with restarting an initialization
1492 * timer. Only multiply the timeout by two if
1493 * all transports have been tried at the current
1494 * timeout.
1495 */
1496 sctp_cmd_t1_timer_update(asoc,
1497 SCTP_EVENT_TIMEOUT_T1_COOKIE,
1498 "COOKIE");
1499
1500 /* If we've sent any data bundled with
1501 * COOKIE-ECHO we need to resend.
1502 */
1503 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1504 transports) {
1505 sctp_retransmit_mark(&asoc->outqueue, t,
1506 SCTP_RTXR_T1_RTX);
1507 }
1508
1509 sctp_add_cmd_sf(commands,
1510 SCTP_CMD_TIMER_RESTART,
1511 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
1512 break;
1513
1514 case SCTP_CMD_INIT_FAILED:
1515 sctp_cmd_init_failed(commands, asoc, cmd->obj.err);
1516 break;
1517
1518 case SCTP_CMD_ASSOC_FAILED:
1519 sctp_cmd_assoc_failed(commands, asoc, event_type,
1520 subtype, chunk, cmd->obj.err);
1521 break;
1522
1523 case SCTP_CMD_INIT_COUNTER_INC:
1524 asoc->init_err_counter++;
1525 break;
1526
1527 case SCTP_CMD_INIT_COUNTER_RESET:
1528 asoc->init_err_counter = 0;
1529 asoc->init_cycle = 0;
1530 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1531 transports) {
1532 t->init_sent_count = 0;
1533 }
1534 break;
1535
1536 case SCTP_CMD_REPORT_DUP:
1537 sctp_tsnmap_mark_dup(&asoc->peer.tsn_map,
1538 cmd->obj.u32);
1539 break;
1540
1541 case SCTP_CMD_REPORT_BAD_TAG:
1542 SCTP_DEBUG_PRINTK("vtag mismatch!\n");
1543 break;
1544
1545 case SCTP_CMD_STRIKE:
1546 /* Mark one strike against a transport. */
1547 sctp_do_8_2_transport_strike(asoc, cmd->obj.transport,
1548 0);
1549 break;
1550
1551 case SCTP_CMD_TRANSPORT_IDLE:
1552 t = cmd->obj.transport;
1553 sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE);
1554 break;
1555
1556 case SCTP_CMD_TRANSPORT_HB_SENT:
1557 t = cmd->obj.transport;
1558 sctp_do_8_2_transport_strike(asoc, t, 1);
1559 t->hb_sent = 1;
1560 break;
1561
1562 case SCTP_CMD_TRANSPORT_ON:
1563 t = cmd->obj.transport;
1564 sctp_cmd_transport_on(commands, asoc, t, chunk);
1565 break;
1566
1567 case SCTP_CMD_HB_TIMERS_START:
1568 sctp_cmd_hb_timers_start(commands, asoc);
1569 break;
1570
1571 case SCTP_CMD_HB_TIMER_UPDATE:
1572 t = cmd->obj.transport;
1573 sctp_cmd_hb_timer_update(commands, t);
1574 break;
1575
1576 case SCTP_CMD_HB_TIMERS_STOP:
1577 sctp_cmd_hb_timers_stop(commands, asoc);
1578 break;
1579
1580 case SCTP_CMD_REPORT_ERROR:
1581 error = cmd->obj.error;
1582 break;
1583
1584 case SCTP_CMD_PROCESS_CTSN:
1585 /* Dummy up a SACK for processing. */
1586 sackh.cum_tsn_ack = cmd->obj.be32;
1587 sackh.a_rwnd = asoc->peer.rwnd +
1588 asoc->outqueue.outstanding_bytes;
1589 sackh.num_gap_ack_blocks = 0;
1590 sackh.num_dup_tsns = 0;
1591 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK,
1592 SCTP_SACKH(&sackh));
1593 break;
1594
1595 case SCTP_CMD_DISCARD_PACKET:
1596 /* We need to discard the whole packet.
1597 * Uncork the queue since there might be
1598 * responses pending
1599 */
1600 chunk->pdiscard = 1;
1601 if (asoc) {
1602 sctp_outq_uncork(&asoc->outqueue);
1603 local_cork = 0;
1604 }
1605 break;
1606
1607 case SCTP_CMD_RTO_PENDING:
1608 t = cmd->obj.transport;
1609 t->rto_pending = 1;
1610 break;
1611
1612 case SCTP_CMD_PART_DELIVER:
1613 sctp_ulpq_partial_delivery(&asoc->ulpq, cmd->obj.ptr,
1614 GFP_ATOMIC);
1615 break;
1616
1617 case SCTP_CMD_RENEGE:
1618 sctp_ulpq_renege(&asoc->ulpq, cmd->obj.ptr,
1619 GFP_ATOMIC);
1620 break;
1621
1622 case SCTP_CMD_SETUP_T4:
1623 sctp_cmd_setup_t4(commands, asoc, cmd->obj.ptr);
1624 break;
1625
1626 case SCTP_CMD_PROCESS_OPERR:
1627 sctp_cmd_process_operr(commands, asoc, chunk);
1628 break;
1629 case SCTP_CMD_CLEAR_INIT_TAG:
1630 asoc->peer.i.init_tag = 0;
1631 break;
1632 case SCTP_CMD_DEL_NON_PRIMARY:
1633 sctp_cmd_del_non_primary(asoc);
1634 break;
1635 case SCTP_CMD_T3_RTX_TIMERS_STOP:
1636 sctp_cmd_t3_rtx_timers_stop(commands, asoc);
1637 break;
1638 case SCTP_CMD_FORCE_PRIM_RETRAN:
1639 t = asoc->peer.retran_path;
1640 asoc->peer.retran_path = asoc->peer.primary_path;
1641 error = sctp_outq_uncork(&asoc->outqueue);
1642 local_cork = 0;
1643 asoc->peer.retran_path = t;
1644 break;
1645 case SCTP_CMD_SET_SK_ERR:
1646 sctp_cmd_set_sk_err(asoc, cmd->obj.error);
1647 break;
1648 case SCTP_CMD_ASSOC_CHANGE:
1649 sctp_cmd_assoc_change(commands, asoc,
1650 cmd->obj.u8);
1651 break;
1652 case SCTP_CMD_ADAPTATION_IND:
1653 sctp_cmd_adaptation_ind(commands, asoc);
1654 break;
1655
1656 case SCTP_CMD_ASSOC_SHKEY:
1657 error = sctp_auth_asoc_init_active_key(asoc,
1658 GFP_ATOMIC);
1659 break;
1660 case SCTP_CMD_UPDATE_INITTAG:
1661 asoc->peer.i.init_tag = cmd->obj.u32;
1662 break;
1663 case SCTP_CMD_SEND_MSG:
1664 if (!asoc->outqueue.cork) {
1665 sctp_outq_cork(&asoc->outqueue);
1666 local_cork = 1;
1667 }
1668 error = sctp_cmd_send_msg(asoc, cmd->obj.msg);
1669 break;
1670 case SCTP_CMD_SEND_NEXT_ASCONF:
1671 sctp_cmd_send_asconf(asoc);
1672 break;
1673 case SCTP_CMD_PURGE_ASCONF_QUEUE:
1674 sctp_asconf_queue_teardown(asoc);
1675 break;
1676 default:
1677 pr_warn("Impossible command: %u, %p\n",
1678 cmd->verb, cmd->obj.ptr);
1679 break;
1680 }
1681
1682 if (error)
1683 break;
1684 }
1685
1686 out:
1687 /* If this is in response to a received chunk, wait until
1688 * we are done with the packet to open the queue so that we don't
1689 * send multiple packets in response to a single request.
1690 */
1691 if (asoc && SCTP_EVENT_T_CHUNK == event_type && chunk) {
1692 if (chunk->end_of_packet || chunk->singleton)
1693 error = sctp_outq_uncork(&asoc->outqueue);
1694 } else if (local_cork)
1695 error = sctp_outq_uncork(&asoc->outqueue);
1696 return error;
1697 nomem:
1698 error = -ENOMEM;
1699 goto out;
1700 }
1701
x86 "subsystem" repository