?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris...
[linux/fpc-iii.git] / net / sctp / sm_sideeffect.c
blobbd859154000e47cccdae4f9f5e4353ba3cb83fd0
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, see
26 * <http://www.gnu.org/licenses/>.
27 *
28 * Please send any bug reports or fixes you make to the
29 * email address(es):
30 * lksctp developers <linux-sctp@vger.kernel.org>
31 *
32 * Written or modified by:
33 * La Monte H.P. Yarroll <piggy@acm.org>
34 * Karl Knutson <karl@athena.chicago.il.us>
35 * Jon Grimm <jgrimm@austin.ibm.com>
36 * Hui Huang <hui.huang@nokia.com>
37 * Dajiang Zhang <dajiang.zhang@nokia.com>
38 * Daisy Chang <daisyc@us.ibm.com>
39 * Sridhar Samudrala <sri@us.ibm.com>
40 * Ardelle Fan <ardelle.fan@intel.com>
41 */
42
43 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
44
45 #include <linux/skbuff.h>
46 #include <linux/types.h>
47 #include <linux/socket.h>
48 #include <linux/ip.h>
49 #include <linux/gfp.h>
50 #include <net/sock.h>
51 #include <net/sctp/sctp.h>
52 #include <net/sctp/sm.h>
53
54 static int sctp_cmd_interpreter(sctp_event_t event_type,
55 sctp_subtype_t subtype,
56 sctp_state_t state,
57 struct sctp_endpoint *ep,
58 struct sctp_association *asoc,
59 void *event_arg,
60 sctp_disposition_t status,
61 sctp_cmd_seq_t *commands,
62 gfp_t gfp);
63 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
64 sctp_state_t state,
65 struct sctp_endpoint *ep,
66 struct sctp_association *asoc,
67 void *event_arg,
68 sctp_disposition_t status,
69 sctp_cmd_seq_t *commands,
70 gfp_t gfp);
71
72 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds,
73 struct sctp_transport *t);
74 /********************************************************************
75 * Helper functions
76 ********************************************************************/
77
78 /* A helper function for delayed processing of INET ECN CE bit. */
79 static void sctp_do_ecn_ce_work(struct sctp_association *asoc,
80 __u32 lowest_tsn)
81 {
82 /* Save the TSN away for comparison when we receive CWR */
83
84 asoc->last_ecne_tsn = lowest_tsn;
85 asoc->need_ecne = 1;
86 }
87
88 /* Helper function for delayed processing of SCTP ECNE chunk. */
89 /* RFC 2960 Appendix A
90 *
91 * RFC 2481 details a specific bit for a sender to send in
92 * the header of its next outbound TCP segment to indicate to
93 * its peer that it has reduced its congestion window. This
94 * is termed the CWR bit. For SCTP the same indication is made
95 * by including the CWR chunk. This chunk contains one data
96 * element, i.e. the TSN number that was sent in the ECNE chunk.
97 * This element represents the lowest TSN number in the datagram
98 * that was originally marked with the CE bit.
99 */
100 static struct sctp_chunk *sctp_do_ecn_ecne_work(struct sctp_association *asoc,
101 __u32 lowest_tsn,
102 struct sctp_chunk *chunk)
103 {
104 struct sctp_chunk *repl;
105
106 /* Our previously transmitted packet ran into some congestion
107 * so we should take action by reducing cwnd and ssthresh
108 * and then ACK our peer that we we've done so by
109 * sending a CWR.
110 */
111
112 /* First, try to determine if we want to actually lower
113 * our cwnd variables. Only lower them if the ECNE looks more
114 * recent than the last response.
115 */
116 if (TSN_lt(asoc->last_cwr_tsn, lowest_tsn)) {
117 struct sctp_transport *transport;
118
119 /* Find which transport's congestion variables
120 * need to be adjusted.
121 */
122 transport = sctp_assoc_lookup_tsn(asoc, lowest_tsn);
123
124 /* Update the congestion variables. */
125 if (transport)
126 sctp_transport_lower_cwnd(transport,
127 SCTP_LOWER_CWND_ECNE);
128 asoc->last_cwr_tsn = lowest_tsn;
129 }
130
131 /* Always try to quiet the other end. In case of lost CWR,
132 * resend last_cwr_tsn.
133 */
134 repl = sctp_make_cwr(asoc, asoc->last_cwr_tsn, chunk);
135
136 /* If we run out of memory, it will look like a lost CWR. We'll
137 * get back in sync eventually.
138 */
139 return repl;
140 }
141
142 /* Helper function to do delayed processing of ECN CWR chunk. */
143 static void sctp_do_ecn_cwr_work(struct sctp_association *asoc,
144 __u32 lowest_tsn)
145 {
146 /* Turn off ECNE getting auto-prepended to every outgoing
147 * packet
148 */
149 asoc->need_ecne = 0;
150 }
151
152 /* Generate SACK if necessary. We call this at the end of a packet. */
153 static int sctp_gen_sack(struct sctp_association *asoc, int force,
154 sctp_cmd_seq_t *commands)
155 {
156 __u32 ctsn, max_tsn_seen;
157 struct sctp_chunk *sack;
158 struct sctp_transport *trans = asoc->peer.last_data_from;
159 int error = 0;
160
161 if (force ||
162 (!trans && (asoc->param_flags & SPP_SACKDELAY_DISABLE)) ||
163 (trans && (trans->param_flags & SPP_SACKDELAY_DISABLE)))
164 asoc->peer.sack_needed = 1;
165
166 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
167 max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
168
169 /* From 12.2 Parameters necessary per association (i.e. the TCB):
170 *
171 * Ack State : This flag indicates if the next received packet
172 * : is to be responded to with a SACK. ...
173 * : When DATA chunks are out of order, SACK's
174 * : are not delayed (see Section 6).
175 *
176 * [This is actually not mentioned in Section 6, but we
177 * implement it here anyway. --piggy]
178 */
179 if (max_tsn_seen != ctsn)
180 asoc->peer.sack_needed = 1;
181
182 /* From 6.2 Acknowledgement on Reception of DATA Chunks:
183 *
184 * Section 4.2 of [RFC2581] SHOULD be followed. Specifically,
185 * an acknowledgement SHOULD be generated for at least every
186 * second packet (not every second DATA chunk) received, and
187 * SHOULD be generated within 200 ms of the arrival of any
188 * unacknowledged DATA chunk. ...
189 */
190 if (!asoc->peer.sack_needed) {
191 asoc->peer.sack_cnt++;
192
193 /* Set the SACK delay timeout based on the
194 * SACK delay for the last transport
195 * data was received from, or the default
196 * for the association.
197 */
198 if (trans) {
199 /* We will need a SACK for the next packet. */
200 if (asoc->peer.sack_cnt >= trans->sackfreq - 1)
201 asoc->peer.sack_needed = 1;
202
203 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
204 trans->sackdelay;
205 } else {
206 /* We will need a SACK for the next packet. */
207 if (asoc->peer.sack_cnt >= asoc->sackfreq - 1)
208 asoc->peer.sack_needed = 1;
209
210 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
211 asoc->sackdelay;
212 }
213
214 /* Restart the SACK timer. */
215 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
216 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
217 } else {
218 asoc->a_rwnd = asoc->rwnd;
219 sack = sctp_make_sack(asoc);
220 if (!sack)
221 goto nomem;
222
223 asoc->peer.sack_needed = 0;
224 asoc->peer.sack_cnt = 0;
225
226 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(sack));
227
228 /* Stop the SACK timer. */
229 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
230 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
231 }
232
233 return error;
234 nomem:
235 error = -ENOMEM;
236 return error;
237 }
238
239 /* When the T3-RTX timer expires, it calls this function to create the
240 * relevant state machine event.
241 */
242 void sctp_generate_t3_rtx_event(unsigned long peer)
243 {
244 int error;
245 struct sctp_transport *transport = (struct sctp_transport *) peer;
246 struct sctp_association *asoc = transport->asoc;
247 struct net *net = sock_net(asoc->base.sk);
248
249 /* Check whether a task is in the sock. */
250
251 bh_lock_sock(asoc->base.sk);
252 if (sock_owned_by_user(asoc->base.sk)) {
253 pr_debug("%s: sock is busy\n", __func__);
254
255 /* Try again later. */
256 if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20)))
257 sctp_transport_hold(transport);
258 goto out_unlock;
259 }
260
261 /* Is this transport really dead and just waiting around for
262 * the timer to let go of the reference?
263 */
264 if (transport->dead)
265 goto out_unlock;
266
267 /* Run through the state machine. */
268 error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
269 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX),
270 asoc->state,
271 asoc->ep, asoc,
272 transport, GFP_ATOMIC);
273
274 if (error)
275 asoc->base.sk->sk_err = -error;
276
277 out_unlock:
278 bh_unlock_sock(asoc->base.sk);
279 sctp_transport_put(transport);
280 }
281
282 /* This is a sa interface for producing timeout events. It works
283 * for timeouts which use the association as their parameter.
284 */
285 static void sctp_generate_timeout_event(struct sctp_association *asoc,
286 sctp_event_timeout_t timeout_type)
287 {
288 struct net *net = sock_net(asoc->base.sk);
289 int error = 0;
290
291 bh_lock_sock(asoc->base.sk);
292 if (sock_owned_by_user(asoc->base.sk)) {
293 pr_debug("%s: sock is busy: timer %d\n", __func__,
294 timeout_type);
295
296 /* Try again later. */
297 if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20)))
298 sctp_association_hold(asoc);
299 goto out_unlock;
300 }
301
302 /* Is this association really dead and just waiting around for
303 * the timer to let go of the reference?
304 */
305 if (asoc->base.dead)
306 goto out_unlock;
307
308 /* Run through the state machine. */
309 error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
310 SCTP_ST_TIMEOUT(timeout_type),
311 asoc->state, asoc->ep, asoc,
312 (void *)timeout_type, GFP_ATOMIC);
313
314 if (error)
315 asoc->base.sk->sk_err = -error;
316
317 out_unlock:
318 bh_unlock_sock(asoc->base.sk);
319 sctp_association_put(asoc);
320 }
321
322 static void sctp_generate_t1_cookie_event(unsigned long data)
323 {
324 struct sctp_association *asoc = (struct sctp_association *) data;
325 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE);
326 }
327
328 static void sctp_generate_t1_init_event(unsigned long data)
329 {
330 struct sctp_association *asoc = (struct sctp_association *) data;
331 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT);
332 }
333
334 static void sctp_generate_t2_shutdown_event(unsigned long data)
335 {
336 struct sctp_association *asoc = (struct sctp_association *) data;
337 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN);
338 }
339
340 static void sctp_generate_t4_rto_event(unsigned long data)
341 {
342 struct sctp_association *asoc = (struct sctp_association *) data;
343 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO);
344 }
345
346 static void sctp_generate_t5_shutdown_guard_event(unsigned long data)
347 {
348 struct sctp_association *asoc = (struct sctp_association *)data;
349 sctp_generate_timeout_event(asoc,
350 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD);
351
352 } /* sctp_generate_t5_shutdown_guard_event() */
353
354 static void sctp_generate_autoclose_event(unsigned long data)
355 {
356 struct sctp_association *asoc = (struct sctp_association *) data;
357 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE);
358 }
359
360 /* Generate a heart beat event. If the sock is busy, reschedule. Make
361 * sure that the transport is still valid.
362 */
363 void sctp_generate_heartbeat_event(unsigned long data)
364 {
365 int error = 0;
366 struct sctp_transport *transport = (struct sctp_transport *) data;
367 struct sctp_association *asoc = transport->asoc;
368 struct net *net = sock_net(asoc->base.sk);
369
370 bh_lock_sock(asoc->base.sk);
371 if (sock_owned_by_user(asoc->base.sk)) {
372 pr_debug("%s: sock is busy\n", __func__);
373
374 /* Try again later. */
375 if (!mod_timer(&transport->hb_timer, jiffies + (HZ/20)))
376 sctp_transport_hold(transport);
377 goto out_unlock;
378 }
379
380 /* Is this structure just waiting around for us to actually
381 * get destroyed?
382 */
383 if (transport->dead)
384 goto out_unlock;
385
386 error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
387 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT),
388 asoc->state, asoc->ep, asoc,
389 transport, GFP_ATOMIC);
390
391 if (error)
392 asoc->base.sk->sk_err = -error;
393
394 out_unlock:
395 bh_unlock_sock(asoc->base.sk);
396 sctp_transport_put(transport);
397 }
398
399 /* Handle the timeout of the ICMP protocol unreachable timer. Trigger
400 * the correct state machine transition that will close the association.
401 */
402 void sctp_generate_proto_unreach_event(unsigned long data)
403 {
404 struct sctp_transport *transport = (struct sctp_transport *) data;
405 struct sctp_association *asoc = transport->asoc;
406 struct net *net = sock_net(asoc->base.sk);
407
408 bh_lock_sock(asoc->base.sk);
409 if (sock_owned_by_user(asoc->base.sk)) {
410 pr_debug("%s: sock is busy\n", __func__);
411
412 /* Try again later. */
413 if (!mod_timer(&transport->proto_unreach_timer,
414 jiffies + (HZ/20)))
415 sctp_association_hold(asoc);
416 goto out_unlock;
417 }
418
419 /* Is this structure just waiting around for us to actually
420 * get destroyed?
421 */
422 if (asoc->base.dead)
423 goto out_unlock;
424
425 sctp_do_sm(net, SCTP_EVENT_T_OTHER,
426 SCTP_ST_OTHER(SCTP_EVENT_ICMP_PROTO_UNREACH),
427 asoc->state, asoc->ep, asoc, transport, GFP_ATOMIC);
428
429 out_unlock:
430 bh_unlock_sock(asoc->base.sk);
431 sctp_association_put(asoc);
432 }
433
434
435 /* Inject a SACK Timeout event into the state machine. */
436 static void sctp_generate_sack_event(unsigned long data)
437 {
438 struct sctp_association *asoc = (struct sctp_association *) data;
439 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK);
440 }
441
442 sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = {
443 NULL,
444 sctp_generate_t1_cookie_event,
445 sctp_generate_t1_init_event,
446 sctp_generate_t2_shutdown_event,
447 NULL,
448 sctp_generate_t4_rto_event,
449 sctp_generate_t5_shutdown_guard_event,
450 NULL,
451 sctp_generate_sack_event,
452 sctp_generate_autoclose_event,
453 };
454
455
456 /* RFC 2960 8.2 Path Failure Detection
457 *
458 * When its peer endpoint is multi-homed, an endpoint should keep a
459 * error counter for each of the destination transport addresses of the
460 * peer endpoint.
461 *
462 * Each time the T3-rtx timer expires on any address, or when a
463 * HEARTBEAT sent to an idle address is not acknowledged within a RTO,
464 * the error counter of that destination address will be incremented.
465 * When the value in the error counter exceeds the protocol parameter
466 * 'Path.Max.Retrans' of that destination address, the endpoint should
467 * mark the destination transport address as inactive, and a
468 * notification SHOULD be sent to the upper layer.
469 *
470 */
471 static void sctp_do_8_2_transport_strike(sctp_cmd_seq_t *commands,
472 struct sctp_association *asoc,
473 struct sctp_transport *transport,
474 int is_hb)
475 {
476 /* The check for association's overall error counter exceeding the
477 * threshold is done in the state function.
478 */
479 /* We are here due to a timer expiration. If the timer was
480 * not a HEARTBEAT, then normal error tracking is done.
481 * If the timer was a heartbeat, we only increment error counts
482 * when we already have an outstanding HEARTBEAT that has not
483 * been acknowledged.
484 * Additionally, some tranport states inhibit error increments.
485 */
486 if (!is_hb) {
487 asoc->overall_error_count++;
488 if (transport->state != SCTP_INACTIVE)
489 transport->error_count++;
490 } else if (transport->hb_sent) {
491 if (transport->state != SCTP_UNCONFIRMED)
492 asoc->overall_error_count++;
493 if (transport->state != SCTP_INACTIVE)
494 transport->error_count++;
495 }
496
497 /* If the transport error count is greater than the pf_retrans
498 * threshold, and less than pathmaxrtx, then mark this transport
499 * as Partially Failed, ee SCTP Quick Failover Draft, secon 5.1,
500 * point 1
501 */
502 if ((transport->state != SCTP_PF) &&
503 (asoc->pf_retrans < transport->pathmaxrxt) &&
504 (transport->error_count > asoc->pf_retrans)) {
505
506 sctp_assoc_control_transport(asoc, transport,
507 SCTP_TRANSPORT_PF,
508 0);
509
510 /* Update the hb timer to resend a heartbeat every rto */
511 sctp_cmd_hb_timer_update(commands, transport);
512 }
513
514 if (transport->state != SCTP_INACTIVE &&
515 (transport->error_count > transport->pathmaxrxt)) {
516 pr_debug("%s: association:%p transport addr:%pISpc failed\n",
517 __func__, asoc, &transport->ipaddr.sa);
518
519 sctp_assoc_control_transport(asoc, transport,
520 SCTP_TRANSPORT_DOWN,
521 SCTP_FAILED_THRESHOLD);
522 }
523
524 /* E2) For the destination address for which the timer
525 * expires, set RTO <- RTO * 2 ("back off the timer"). The
526 * maximum value discussed in rule C7 above (RTO.max) may be
527 * used to provide an upper bound to this doubling operation.
528 *
529 * Special Case: the first HB doesn't trigger exponential backoff.
530 * The first unacknowledged HB triggers it. We do this with a flag
531 * that indicates that we have an outstanding HB.
532 */
533 if (!is_hb || transport->hb_sent) {
534 transport->rto = min((transport->rto * 2), transport->asoc->rto_max);
535 sctp_max_rto(asoc, transport);
536 }
537 }
538
539 /* Worker routine to handle INIT command failure. */
540 static void sctp_cmd_init_failed(sctp_cmd_seq_t *commands,
541 struct sctp_association *asoc,
542 unsigned int error)
543 {
544 struct sctp_ulpevent *event;
545
546 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_CANT_STR_ASSOC,
547 (__u16)error, 0, 0, NULL,
548 GFP_ATOMIC);
549
550 if (event)
551 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
552 SCTP_ULPEVENT(event));
553
554 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
555 SCTP_STATE(SCTP_STATE_CLOSED));
556
557 /* SEND_FAILED sent later when cleaning up the association. */
558 asoc->outqueue.error = error;
559 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
560 }
561
562 /* Worker routine to handle SCTP_CMD_ASSOC_FAILED. */
563 static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands,
564 struct sctp_association *asoc,
565 sctp_event_t event_type,
566 sctp_subtype_t subtype,
567 struct sctp_chunk *chunk,
568 unsigned int error)
569 {
570 struct sctp_ulpevent *event;
571 struct sctp_chunk *abort;
572 /* Cancel any partial delivery in progress. */
573 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
574
575 if (event_type == SCTP_EVENT_T_CHUNK && subtype.chunk == SCTP_CID_ABORT)
576 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
577 (__u16)error, 0, 0, chunk,
578 GFP_ATOMIC);
579 else
580 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
581 (__u16)error, 0, 0, NULL,
582 GFP_ATOMIC);
583 if (event)
584 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
585 SCTP_ULPEVENT(event));
586
587 if (asoc->overall_error_count >= asoc->max_retrans) {
588 abort = sctp_make_violation_max_retrans(asoc, chunk);
589 if (abort)
590 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
591 SCTP_CHUNK(abort));
592 }
593
594 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
595 SCTP_STATE(SCTP_STATE_CLOSED));
596
597 /* SEND_FAILED sent later when cleaning up the association. */
598 asoc->outqueue.error = error;
599 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
600 }
601
602 /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT
603 * inside the cookie. In reality, this is only used for INIT-ACK processing
604 * since all other cases use "temporary" associations and can do all
605 * their work in statefuns directly.
606 */
607 static int sctp_cmd_process_init(sctp_cmd_seq_t *commands,
608 struct sctp_association *asoc,
609 struct sctp_chunk *chunk,
610 sctp_init_chunk_t *peer_init,
611 gfp_t gfp)
612 {
613 int error;
614
615 /* We only process the init as a sideeffect in a single
616 * case. This is when we process the INIT-ACK. If we
617 * fail during INIT processing (due to malloc problems),
618 * just return the error and stop processing the stack.
619 */
620 if (!sctp_process_init(asoc, chunk, sctp_source(chunk), peer_init, gfp))
621 error = -ENOMEM;
622 else
623 error = 0;
624
625 return error;
626 }
627
628 /* Helper function to break out starting up of heartbeat timers. */
629 static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds,
630 struct sctp_association *asoc)
631 {
632 struct sctp_transport *t;
633
634 /* Start a heartbeat timer for each transport on the association.
635 * hold a reference on the transport to make sure none of
636 * the needed data structures go away.
637 */
638 list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) {
639
640 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
641 sctp_transport_hold(t);
642 }
643 }
644
645 static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds,
646 struct sctp_association *asoc)
647 {
648 struct sctp_transport *t;
649
650 /* Stop all heartbeat timers. */
651
652 list_for_each_entry(t, &asoc->peer.transport_addr_list,
653 transports) {
654 if (del_timer(&t->hb_timer))
655 sctp_transport_put(t);
656 }
657 }
658
659 /* Helper function to stop any pending T3-RTX timers */
660 static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds,
661 struct sctp_association *asoc)
662 {
663 struct sctp_transport *t;
664
665 list_for_each_entry(t, &asoc->peer.transport_addr_list,
666 transports) {
667 if (del_timer(&t->T3_rtx_timer))
668 sctp_transport_put(t);
669 }
670 }
671
672
673 /* Helper function to update the heartbeat timer. */
674 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds,
675 struct sctp_transport *t)
676 {
677 /* Update the heartbeat timer. */
678 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
679 sctp_transport_hold(t);
680 }
681
682 /* Helper function to handle the reception of an HEARTBEAT ACK. */
683 static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds,
684 struct sctp_association *asoc,
685 struct sctp_transport *t,
686 struct sctp_chunk *chunk)
687 {
688 sctp_sender_hb_info_t *hbinfo;
689 int was_unconfirmed = 0;
690
691 /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the
692 * HEARTBEAT should clear the error counter of the destination
693 * transport address to which the HEARTBEAT was sent.
694 */
695 t->error_count = 0;
696
697 /*
698 * Although RFC4960 specifies that the overall error count must
699 * be cleared when a HEARTBEAT ACK is received, we make an
700 * exception while in SHUTDOWN PENDING. If the peer keeps its
701 * window shut forever, we may never be able to transmit our
702 * outstanding data and rely on the retransmission limit be reached
703 * to shutdown the association.
704 */
705 if (t->asoc->state != SCTP_STATE_SHUTDOWN_PENDING)
706 t->asoc->overall_error_count = 0;
707
708 /* Clear the hb_sent flag to signal that we had a good
709 * acknowledgement.
710 */
711 t->hb_sent = 0;
712
713 /* Mark the destination transport address as active if it is not so
714 * marked.
715 */
716 if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED)) {
717 was_unconfirmed = 1;
718 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
719 SCTP_HEARTBEAT_SUCCESS);
720 }
721
722 if (t->state == SCTP_PF)
723 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
724 SCTP_HEARTBEAT_SUCCESS);
725
726 /* HB-ACK was received for a the proper HB. Consider this
727 * forward progress.
728 */
729 if (t->dst)
730 dst_confirm(t->dst);
731
732 /* The receiver of the HEARTBEAT ACK should also perform an
733 * RTT measurement for that destination transport address
734 * using the time value carried in the HEARTBEAT ACK chunk.
735 * If the transport's rto_pending variable has been cleared,
736 * it was most likely due to a retransmit. However, we want
737 * to re-enable it to properly update the rto.
738 */
739 if (t->rto_pending == 0)
740 t->rto_pending = 1;
741
742 hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data;
743 sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at));
744
745 /* Update the heartbeat timer. */
746 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
747 sctp_transport_hold(t);
748
749 if (was_unconfirmed && asoc->peer.transport_count == 1)
750 sctp_transport_immediate_rtx(t);
751 }
752
753
754 /* Helper function to process the process SACK command. */
755 static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds,
756 struct sctp_association *asoc,
757 struct sctp_chunk *chunk)
758 {
759 int err = 0;
760
761 if (sctp_outq_sack(&asoc->outqueue, chunk)) {
762 struct net *net = sock_net(asoc->base.sk);
763
764 /* There are no more TSNs awaiting SACK. */
765 err = sctp_do_sm(net, SCTP_EVENT_T_OTHER,
766 SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN),
767 asoc->state, asoc->ep, asoc, NULL,
768 GFP_ATOMIC);
769 }
770
771 return err;
772 }
773
774 /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set
775 * the transport for a shutdown chunk.
776 */
777 static void sctp_cmd_setup_t2(sctp_cmd_seq_t *cmds,
778 struct sctp_association *asoc,
779 struct sctp_chunk *chunk)
780 {
781 struct sctp_transport *t;
782
783 if (chunk->transport)
784 t = chunk->transport;
785 else {
786 t = sctp_assoc_choose_alter_transport(asoc,
787 asoc->shutdown_last_sent_to);
788 chunk->transport = t;
789 }
790 asoc->shutdown_last_sent_to = t;
791 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto;
792 }
793
794 /* Helper function to change the state of an association. */
795 static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds,
796 struct sctp_association *asoc,
797 sctp_state_t state)
798 {
799 struct sock *sk = asoc->base.sk;
800
801 asoc->state = state;
802
803 pr_debug("%s: asoc:%p[%s]\n", __func__, asoc, sctp_state_tbl[state]);
804
805 if (sctp_style(sk, TCP)) {
806 /* Change the sk->sk_state of a TCP-style socket that has
807 * successfully completed a connect() call.
808 */
809 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED))
810 sk->sk_state = SCTP_SS_ESTABLISHED;
811
812 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */
813 if (sctp_state(asoc, SHUTDOWN_RECEIVED) &&
814 sctp_sstate(sk, ESTABLISHED))
815 sk->sk_shutdown |= RCV_SHUTDOWN;
816 }
817
818 if (sctp_state(asoc, COOKIE_WAIT)) {
819 /* Reset init timeouts since they may have been
820 * increased due to timer expirations.
821 */
822 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
823 asoc->rto_initial;
824 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
825 asoc->rto_initial;
826 }
827
828 if (sctp_state(asoc, ESTABLISHED) ||
829 sctp_state(asoc, CLOSED) ||
830 sctp_state(asoc, SHUTDOWN_RECEIVED)) {
831 /* Wake up any processes waiting in the asoc's wait queue in
832 * sctp_wait_for_connect() or sctp_wait_for_sndbuf().
833 */
834 if (waitqueue_active(&asoc->wait))
835 wake_up_interruptible(&asoc->wait);
836
837 /* Wake up any processes waiting in the sk's sleep queue of
838 * a TCP-style or UDP-style peeled-off socket in
839 * sctp_wait_for_accept() or sctp_wait_for_packet().
840 * For a UDP-style socket, the waiters are woken up by the
841 * notifications.
842 */
843 if (!sctp_style(sk, UDP))
844 sk->sk_state_change(sk);
845 }
846 }
847
848 /* Helper function to delete an association. */
849 static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds,
850 struct sctp_association *asoc)
851 {
852 struct sock *sk = asoc->base.sk;
853
854 /* If it is a non-temporary association belonging to a TCP-style
855 * listening socket that is not closed, do not free it so that accept()
856 * can pick it up later.
857 */
858 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) &&
859 (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK))
860 return;
861
862 sctp_unhash_established(asoc);
863 sctp_association_free(asoc);
864 }
865
866 /*
867 * ADDIP Section 4.1 ASCONF Chunk Procedures
868 * A4) Start a T-4 RTO timer, using the RTO value of the selected
869 * destination address (we use active path instead of primary path just
870 * because primary path may be inactive.
871 */
872 static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds,
873 struct sctp_association *asoc,
874 struct sctp_chunk *chunk)
875 {
876 struct sctp_transport *t;
877
878 t = sctp_assoc_choose_alter_transport(asoc, chunk->transport);
879 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto;
880 chunk->transport = t;
881 }
882
883 /* Process an incoming Operation Error Chunk. */
884 static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds,
885 struct sctp_association *asoc,
886 struct sctp_chunk *chunk)
887 {
888 struct sctp_errhdr *err_hdr;
889 struct sctp_ulpevent *ev;
890
891 while (chunk->chunk_end > chunk->skb->data) {
892 err_hdr = (struct sctp_errhdr *)(chunk->skb->data);
893
894 ev = sctp_ulpevent_make_remote_error(asoc, chunk, 0,
895 GFP_ATOMIC);
896 if (!ev)
897 return;
898
899 sctp_ulpq_tail_event(&asoc->ulpq, ev);
900
901 switch (err_hdr->cause) {
902 case SCTP_ERROR_UNKNOWN_CHUNK:
903 {
904 sctp_chunkhdr_t *unk_chunk_hdr;
905
906 unk_chunk_hdr = (sctp_chunkhdr_t *)err_hdr->variable;
907 switch (unk_chunk_hdr->type) {
908 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with
909 * an ERROR chunk reporting that it did not recognized
910 * the ASCONF chunk type, the sender of the ASCONF MUST
911 * NOT send any further ASCONF chunks and MUST stop its
912 * T-4 timer.
913 */
914 case SCTP_CID_ASCONF:
915 if (asoc->peer.asconf_capable == 0)
916 break;
917
918 asoc->peer.asconf_capable = 0;
919 sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP,
920 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
921 break;
922 default:
923 break;
924 }
925 break;
926 }
927 default:
928 break;
929 }
930 }
931 }
932
933 /* Process variable FWDTSN chunk information. */
934 static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq,
935 struct sctp_chunk *chunk)
936 {
937 struct sctp_fwdtsn_skip *skip;
938 /* Walk through all the skipped SSNs */
939 sctp_walk_fwdtsn(skip, chunk) {
940 sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn));
941 }
942 }
943
944 /* Helper function to remove the association non-primary peer
945 * transports.
946 */
947 static void sctp_cmd_del_non_primary(struct sctp_association *asoc)
948 {
949 struct sctp_transport *t;
950 struct list_head *pos;
951 struct list_head *temp;
952
953 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
954 t = list_entry(pos, struct sctp_transport, transports);
955 if (!sctp_cmp_addr_exact(&t->ipaddr,
956 &asoc->peer.primary_addr)) {
957 sctp_assoc_del_peer(asoc, &t->ipaddr);
958 }
959 }
960 }
961
962 /* Helper function to set sk_err on a 1-1 style socket. */
963 static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error)
964 {
965 struct sock *sk = asoc->base.sk;
966
967 if (!sctp_style(sk, UDP))
968 sk->sk_err = error;
969 }
970
971 /* Helper function to generate an association change event */
972 static void sctp_cmd_assoc_change(sctp_cmd_seq_t *commands,
973 struct sctp_association *asoc,
974 u8 state)
975 {
976 struct sctp_ulpevent *ev;
977
978 ev = sctp_ulpevent_make_assoc_change(asoc, 0, state, 0,
979 asoc->c.sinit_num_ostreams,
980 asoc->c.sinit_max_instreams,
981 NULL, GFP_ATOMIC);
982 if (ev)
983 sctp_ulpq_tail_event(&asoc->ulpq, ev);
984 }
985
986 /* Helper function to generate an adaptation indication event */
987 static void sctp_cmd_adaptation_ind(sctp_cmd_seq_t *commands,
988 struct sctp_association *asoc)
989 {
990 struct sctp_ulpevent *ev;
991
992 ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC);
993
994 if (ev)
995 sctp_ulpq_tail_event(&asoc->ulpq, ev);
996 }
997
998
999 static void sctp_cmd_t1_timer_update(struct sctp_association *asoc,
1000 sctp_event_timeout_t timer,
1001 char *name)
1002 {
1003 struct sctp_transport *t;
1004
1005 t = asoc->init_last_sent_to;
1006 asoc->init_err_counter++;
1007
1008 if (t->init_sent_count > (asoc->init_cycle + 1)) {
1009 asoc->timeouts[timer] *= 2;
1010 if (asoc->timeouts[timer] > asoc->max_init_timeo) {
1011 asoc->timeouts[timer] = asoc->max_init_timeo;
1012 }
1013 asoc->init_cycle++;
1014
1015 pr_debug("%s: T1[%s] timeout adjustment init_err_counter:%d"
1016 " cycle:%d timeout:%ld\n", __func__, name,
1017 asoc->init_err_counter, asoc->init_cycle,
1018 asoc->timeouts[timer]);
1019 }
1020
1021 }
1022
1023 /* Send the whole message, chunk by chunk, to the outqueue.
1024 * This way the whole message is queued up and bundling if
1025 * encouraged for small fragments.
1026 */
1027 static int sctp_cmd_send_msg(struct sctp_association *asoc,
1028 struct sctp_datamsg *msg)
1029 {
1030 struct sctp_chunk *chunk;
1031 int error = 0;
1032
1033 list_for_each_entry(chunk, &msg->chunks, frag_list) {
1034 error = sctp_outq_tail(&asoc->outqueue, chunk);
1035 if (error)
1036 break;
1037 }
1038
1039 return error;
1040 }
1041
1042
1043 /* Sent the next ASCONF packet currently stored in the association.
1044 * This happens after the ASCONF_ACK was succeffully processed.
1045 */
1046 static void sctp_cmd_send_asconf(struct sctp_association *asoc)
1047 {
1048 struct net *net = sock_net(asoc->base.sk);
1049
1050 /* Send the next asconf chunk from the addip chunk
1051 * queue.
1052 */
1053 if (!list_empty(&asoc->addip_chunk_list)) {
1054 struct list_head *entry = asoc->addip_chunk_list.next;
1055 struct sctp_chunk *asconf = list_entry(entry,
1056 struct sctp_chunk, list);
1057 list_del_init(entry);
1058
1059 /* Hold the chunk until an ASCONF_ACK is received. */
1060 sctp_chunk_hold(asconf);
1061 if (sctp_primitive_ASCONF(net, asoc, asconf))
1062 sctp_chunk_free(asconf);
1063 else
1064 asoc->addip_last_asconf = asconf;
1065 }
1066 }
1067
1068
1069 /* These three macros allow us to pull the debugging code out of the
1070 * main flow of sctp_do_sm() to keep attention focused on the real
1071 * functionality there.
1072 */
1073 #define debug_pre_sfn() \
1074 pr_debug("%s[pre-fn]: ep:%p, %s, %s, asoc:%p[%s], %s\n", __func__, \
1075 ep, sctp_evttype_tbl[event_type], (*debug_fn)(subtype), \
1076 asoc, sctp_state_tbl[state], state_fn->name)
1077
1078 #define debug_post_sfn() \
1079 pr_debug("%s[post-fn]: asoc:%p, status:%s\n", __func__, asoc, \
1080 sctp_status_tbl[status])
1081
1082 #define debug_post_sfx() \
1083 pr_debug("%s[post-sfx]: error:%d, asoc:%p[%s]\n", __func__, error, \
1084 asoc, sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \
1085 sctp_assoc2id(asoc))) ? asoc->state : SCTP_STATE_CLOSED])
1086
1087 /*
1088 * This is the master state machine processing function.
1089 *
1090 * If you want to understand all of lksctp, this is a
1091 * good place to start.
1092 */
1093 int sctp_do_sm(struct net *net, sctp_event_t event_type, sctp_subtype_t subtype,
1094 sctp_state_t state,
1095 struct sctp_endpoint *ep,
1096 struct sctp_association *asoc,
1097 void *event_arg,
1098 gfp_t gfp)
1099 {
1100 sctp_cmd_seq_t commands;
1101 const sctp_sm_table_entry_t *state_fn;
1102 sctp_disposition_t status;
1103 int error = 0;
1104 typedef const char *(printfn_t)(sctp_subtype_t);
1105 static printfn_t *table[] = {
1106 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname,
1107 };
1108 printfn_t *debug_fn __attribute__ ((unused)) = table[event_type];
1109
1110 /* Look up the state function, run it, and then process the
1111 * side effects. These three steps are the heart of lksctp.
1112 */
1113 state_fn = sctp_sm_lookup_event(net, event_type, state, subtype);
1114
1115 sctp_init_cmd_seq(&commands);
1116
1117 debug_pre_sfn();
1118 status = state_fn->fn(net, ep, asoc, subtype, event_arg, &commands);
1119 debug_post_sfn();
1120
1121 error = sctp_side_effects(event_type, subtype, state,
1122 ep, asoc, event_arg, status,
1123 &commands, gfp);
1124 debug_post_sfx();
1125
1126 return error;
1127 }
1128
1129 /*****************************************************************
1130 * This the master state function side effect processing function.
1131 *****************************************************************/
1132 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
1133 sctp_state_t state,
1134 struct sctp_endpoint *ep,
1135 struct sctp_association *asoc,
1136 void *event_arg,
1137 sctp_disposition_t status,
1138 sctp_cmd_seq_t *commands,
1139 gfp_t gfp)
1140 {
1141 int error;
1142
1143 /* FIXME - Most of the dispositions left today would be categorized
1144 * as "exceptional" dispositions. For those dispositions, it
1145 * may not be proper to run through any of the commands at all.
1146 * For example, the command interpreter might be run only with
1147 * disposition SCTP_DISPOSITION_CONSUME.
1148 */
1149 if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state,
1150 ep, asoc,
1151 event_arg, status,
1152 commands, gfp)))
1153 goto bail;
1154
1155 switch (status) {
1156 case SCTP_DISPOSITION_DISCARD:
1157 pr_debug("%s: ignored sctp protocol event - state:%d, "
1158 "event_type:%d, event_id:%d\n", __func__, state,
1159 event_type, subtype.chunk);
1160 break;
1161
1162 case SCTP_DISPOSITION_NOMEM:
1163 /* We ran out of memory, so we need to discard this
1164 * packet.
1165 */
1166 /* BUG--we should now recover some memory, probably by
1167 * reneging...
1168 */
1169 error = -ENOMEM;
1170 break;
1171
1172 case SCTP_DISPOSITION_DELETE_TCB:
1173 /* This should now be a command. */
1174 break;
1175
1176 case SCTP_DISPOSITION_CONSUME:
1177 case SCTP_DISPOSITION_ABORT:
1178 /*
1179 * We should no longer have much work to do here as the
1180 * real work has been done as explicit commands above.
1181 */
1182 break;
1183
1184 case SCTP_DISPOSITION_VIOLATION:
1185 net_err_ratelimited("protocol violation state %d chunkid %d\n",
1186 state, subtype.chunk);
1187 break;
1188
1189 case SCTP_DISPOSITION_NOT_IMPL:
1190 pr_warn("unimplemented feature in state %d, event_type %d, event_id %d\n",
1191 state, event_type, subtype.chunk);
1192 break;
1193
1194 case SCTP_DISPOSITION_BUG:
1195 pr_err("bug in state %d, event_type %d, event_id %d\n",
1196 state, event_type, subtype.chunk);
1197 BUG();
1198 break;
1199
1200 default:
1201 pr_err("impossible disposition %d in state %d, event_type %d, event_id %d\n",
1202 status, state, event_type, subtype.chunk);
1203 BUG();
1204 break;
1205 }
1206
1207 bail:
1208 return error;
1209 }
1210
1211 /********************************************************************
1212 * 2nd Level Abstractions
1213 ********************************************************************/
1214
1215 /* This is the side-effect interpreter. */
1216 static int sctp_cmd_interpreter(sctp_event_t event_type,
1217 sctp_subtype_t subtype,
1218 sctp_state_t state,
1219 struct sctp_endpoint *ep,
1220 struct sctp_association *asoc,
1221 void *event_arg,
1222 sctp_disposition_t status,
1223 sctp_cmd_seq_t *commands,
1224 gfp_t gfp)
1225 {
1226 int error = 0;
1227 int force;
1228 sctp_cmd_t *cmd;
1229 struct sctp_chunk *new_obj;
1230 struct sctp_chunk *chunk = NULL;
1231 struct sctp_packet *packet;
1232 struct timer_list *timer;
1233 unsigned long timeout;
1234 struct sctp_transport *t;
1235 struct sctp_sackhdr sackh;
1236 int local_cork = 0;
1237
1238 if (SCTP_EVENT_T_TIMEOUT != event_type)
1239 chunk = event_arg;
1240
1241 /* Note: This whole file is a huge candidate for rework.
1242 * For example, each command could either have its own handler, so
1243 * the loop would look like:
1244 * while (cmds)
1245 * cmd->handle(x, y, z)
1246 * --jgrimm
1247 */
1248 while (NULL != (cmd = sctp_next_cmd(commands))) {
1249 switch (cmd->verb) {
1250 case SCTP_CMD_NOP:
1251 /* Do nothing. */
1252 break;
1253
1254 case SCTP_CMD_NEW_ASOC:
1255 /* Register a new association. */
1256 if (local_cork) {
1257 sctp_outq_uncork(&asoc->outqueue);
1258 local_cork = 0;
1259 }
1260
1261 /* Register with the endpoint. */
1262 asoc = cmd->obj.asoc;
1263 BUG_ON(asoc->peer.primary_path == NULL);
1264 sctp_endpoint_add_asoc(ep, asoc);
1265 sctp_hash_established(asoc);
1266 break;
1267
1268 case SCTP_CMD_UPDATE_ASSOC:
1269 sctp_assoc_update(asoc, cmd->obj.asoc);
1270 break;
1271
1272 case SCTP_CMD_PURGE_OUTQUEUE:
1273 sctp_outq_teardown(&asoc->outqueue);
1274 break;
1275
1276 case SCTP_CMD_DELETE_TCB:
1277 if (local_cork) {
1278 sctp_outq_uncork(&asoc->outqueue);
1279 local_cork = 0;
1280 }
1281 /* Delete the current association. */
1282 sctp_cmd_delete_tcb(commands, asoc);
1283 asoc = NULL;
1284 break;
1285
1286 case SCTP_CMD_NEW_STATE:
1287 /* Enter a new state. */
1288 sctp_cmd_new_state(commands, asoc, cmd->obj.state);
1289 break;
1290
1291 case SCTP_CMD_REPORT_TSN:
1292 /* Record the arrival of a TSN. */
1293 error = sctp_tsnmap_mark(&asoc->peer.tsn_map,
1294 cmd->obj.u32, NULL);
1295 break;
1296
1297 case SCTP_CMD_REPORT_FWDTSN:
1298 /* Move the Cumulattive TSN Ack ahead. */
1299 sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32);
1300
1301 /* purge the fragmentation queue */
1302 sctp_ulpq_reasm_flushtsn(&asoc->ulpq, cmd->obj.u32);
1303
1304 /* Abort any in progress partial delivery. */
1305 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
1306 break;
1307
1308 case SCTP_CMD_PROCESS_FWDTSN:
1309 sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.chunk);
1310 break;
1311
1312 case SCTP_CMD_GEN_SACK:
1313 /* Generate a Selective ACK.
1314 * The argument tells us whether to just count
1315 * the packet and MAYBE generate a SACK, or
1316 * force a SACK out.
1317 */
1318 force = cmd->obj.i32;
1319 error = sctp_gen_sack(asoc, force, commands);
1320 break;
1321
1322 case SCTP_CMD_PROCESS_SACK:
1323 /* Process an inbound SACK. */
1324 error = sctp_cmd_process_sack(commands, asoc,
1325 cmd->obj.chunk);
1326 break;
1327
1328 case SCTP_CMD_GEN_INIT_ACK:
1329 /* Generate an INIT ACK chunk. */
1330 new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC,
1331 0);
1332 if (!new_obj)
1333 goto nomem;
1334
1335 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1336 SCTP_CHUNK(new_obj));
1337 break;
1338
1339 case SCTP_CMD_PEER_INIT:
1340 /* Process a unified INIT from the peer.
1341 * Note: Only used during INIT-ACK processing. If
1342 * there is an error just return to the outter
1343 * layer which will bail.
1344 */
1345 error = sctp_cmd_process_init(commands, asoc, chunk,
1346 cmd->obj.init, gfp);
1347 break;
1348
1349 case SCTP_CMD_GEN_COOKIE_ECHO:
1350 /* Generate a COOKIE ECHO chunk. */
1351 new_obj = sctp_make_cookie_echo(asoc, chunk);
1352 if (!new_obj) {
1353 if (cmd->obj.chunk)
1354 sctp_chunk_free(cmd->obj.chunk);
1355 goto nomem;
1356 }
1357 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1358 SCTP_CHUNK(new_obj));
1359
1360 /* If there is an ERROR chunk to be sent along with
1361 * the COOKIE_ECHO, send it, too.
1362 */
1363 if (cmd->obj.chunk)
1364 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1365 SCTP_CHUNK(cmd->obj.chunk));
1366
1367 if (new_obj->transport) {
1368 new_obj->transport->init_sent_count++;
1369 asoc->init_last_sent_to = new_obj->transport;
1370 }
1371
1372 /* FIXME - Eventually come up with a cleaner way to
1373 * enabling COOKIE-ECHO + DATA bundling during
1374 * multihoming stale cookie scenarios, the following
1375 * command plays with asoc->peer.retran_path to
1376 * avoid the problem of sending the COOKIE-ECHO and
1377 * DATA in different paths, which could result
1378 * in the association being ABORTed if the DATA chunk
1379 * is processed first by the server. Checking the
1380 * init error counter simply causes this command
1381 * to be executed only during failed attempts of
1382 * association establishment.
1383 */
1384 if ((asoc->peer.retran_path !=
1385 asoc->peer.primary_path) &&
1386 (asoc->init_err_counter > 0)) {
1387 sctp_add_cmd_sf(commands,
1388 SCTP_CMD_FORCE_PRIM_RETRAN,
1389 SCTP_NULL());
1390 }
1391
1392 break;
1393
1394 case SCTP_CMD_GEN_SHUTDOWN:
1395 /* Generate SHUTDOWN when in SHUTDOWN_SENT state.
1396 * Reset error counts.
1397 */
1398 asoc->overall_error_count = 0;
1399
1400 /* Generate a SHUTDOWN chunk. */
1401 new_obj = sctp_make_shutdown(asoc, chunk);
1402 if (!new_obj)
1403 goto nomem;
1404 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1405 SCTP_CHUNK(new_obj));
1406 break;
1407
1408 case SCTP_CMD_CHUNK_ULP:
1409 /* Send a chunk to the sockets layer. */
1410 pr_debug("%s: sm_sideff: chunk_up:%p, ulpq:%p\n",
1411 __func__, cmd->obj.chunk, &asoc->ulpq);
1412
1413 sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.chunk,
1414 GFP_ATOMIC);
1415 break;
1416
1417 case SCTP_CMD_EVENT_ULP:
1418 /* Send a notification to the sockets layer. */
1419 pr_debug("%s: sm_sideff: event_up:%p, ulpq:%p\n",
1420 __func__, cmd->obj.ulpevent, &asoc->ulpq);
1421
1422 sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ulpevent);
1423 break;
1424
1425 case SCTP_CMD_REPLY:
1426 /* If an caller has not already corked, do cork. */
1427 if (!asoc->outqueue.cork) {
1428 sctp_outq_cork(&asoc->outqueue);
1429 local_cork = 1;
1430 }
1431 /* Send a chunk to our peer. */
1432 error = sctp_outq_tail(&asoc->outqueue, cmd->obj.chunk);
1433 break;
1434
1435 case SCTP_CMD_SEND_PKT:
1436 /* Send a full packet to our peer. */
1437 packet = cmd->obj.packet;
1438 sctp_packet_transmit(packet);
1439 sctp_ootb_pkt_free(packet);
1440 break;
1441
1442 case SCTP_CMD_T1_RETRAN:
1443 /* Mark a transport for retransmission. */
1444 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1445 SCTP_RTXR_T1_RTX);
1446 break;
1447
1448 case SCTP_CMD_RETRAN:
1449 /* Mark a transport for retransmission. */
1450 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1451 SCTP_RTXR_T3_RTX);
1452 break;
1453
1454 case SCTP_CMD_ECN_CE:
1455 /* Do delayed CE processing. */
1456 sctp_do_ecn_ce_work(asoc, cmd->obj.u32);
1457 break;
1458
1459 case SCTP_CMD_ECN_ECNE:
1460 /* Do delayed ECNE processing. */
1461 new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32,
1462 chunk);
1463 if (new_obj)
1464 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1465 SCTP_CHUNK(new_obj));
1466 break;
1467
1468 case SCTP_CMD_ECN_CWR:
1469 /* Do delayed CWR processing. */
1470 sctp_do_ecn_cwr_work(asoc, cmd->obj.u32);
1471 break;
1472
1473 case SCTP_CMD_SETUP_T2:
1474 sctp_cmd_setup_t2(commands, asoc, cmd->obj.chunk);
1475 break;
1476
1477 case SCTP_CMD_TIMER_START_ONCE:
1478 timer = &asoc->timers[cmd->obj.to];
1479
1480 if (timer_pending(timer))
1481 break;
1482 /* fall through */
1483
1484 case SCTP_CMD_TIMER_START:
1485 timer = &asoc->timers[cmd->obj.to];
1486 timeout = asoc->timeouts[cmd->obj.to];
1487 BUG_ON(!timeout);
1488
1489 timer->expires = jiffies + timeout;
1490 sctp_association_hold(asoc);
1491 add_timer(timer);
1492 break;
1493
1494 case SCTP_CMD_TIMER_RESTART:
1495 timer = &asoc->timers[cmd->obj.to];
1496 timeout = asoc->timeouts[cmd->obj.to];
1497 if (!mod_timer(timer, jiffies + timeout))
1498 sctp_association_hold(asoc);
1499 break;
1500
1501 case SCTP_CMD_TIMER_STOP:
1502 timer = &asoc->timers[cmd->obj.to];
1503 if (del_timer(timer))
1504 sctp_association_put(asoc);
1505 break;
1506
1507 case SCTP_CMD_INIT_CHOOSE_TRANSPORT:
1508 chunk = cmd->obj.chunk;
1509 t = sctp_assoc_choose_alter_transport(asoc,
1510 asoc->init_last_sent_to);
1511 asoc->init_last_sent_to = t;
1512 chunk->transport = t;
1513 t->init_sent_count++;
1514 /* Set the new transport as primary */
1515 sctp_assoc_set_primary(asoc, t);
1516 break;
1517
1518 case SCTP_CMD_INIT_RESTART:
1519 /* Do the needed accounting and updates
1520 * associated with restarting an initialization
1521 * timer. Only multiply the timeout by two if
1522 * all transports have been tried at the current
1523 * timeout.
1524 */
1525 sctp_cmd_t1_timer_update(asoc,
1526 SCTP_EVENT_TIMEOUT_T1_INIT,
1527 "INIT");
1528
1529 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
1530 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
1531 break;
1532
1533 case SCTP_CMD_COOKIEECHO_RESTART:
1534 /* Do the needed accounting and updates
1535 * associated with restarting an initialization
1536 * timer. Only multiply the timeout by two if
1537 * all transports have been tried at the current
1538 * timeout.
1539 */
1540 sctp_cmd_t1_timer_update(asoc,
1541 SCTP_EVENT_TIMEOUT_T1_COOKIE,
1542 "COOKIE");
1543
1544 /* If we've sent any data bundled with
1545 * COOKIE-ECHO we need to resend.
1546 */
1547 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1548 transports) {
1549 sctp_retransmit_mark(&asoc->outqueue, t,
1550 SCTP_RTXR_T1_RTX);
1551 }
1552
1553 sctp_add_cmd_sf(commands,
1554 SCTP_CMD_TIMER_RESTART,
1555 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
1556 break;
1557
1558 case SCTP_CMD_INIT_FAILED:
1559 sctp_cmd_init_failed(commands, asoc, cmd->obj.err);
1560 break;
1561
1562 case SCTP_CMD_ASSOC_FAILED:
1563 sctp_cmd_assoc_failed(commands, asoc, event_type,
1564 subtype, chunk, cmd->obj.err);
1565 break;
1566
1567 case SCTP_CMD_INIT_COUNTER_INC:
1568 asoc->init_err_counter++;
1569 break;
1570
1571 case SCTP_CMD_INIT_COUNTER_RESET:
1572 asoc->init_err_counter = 0;
1573 asoc->init_cycle = 0;
1574 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1575 transports) {
1576 t->init_sent_count = 0;
1577 }
1578 break;
1579
1580 case SCTP_CMD_REPORT_DUP:
1581 sctp_tsnmap_mark_dup(&asoc->peer.tsn_map,
1582 cmd->obj.u32);
1583 break;
1584
1585 case SCTP_CMD_REPORT_BAD_TAG:
1586 pr_debug("%s: vtag mismatch!\n", __func__);
1587 break;
1588
1589 case SCTP_CMD_STRIKE:
1590 /* Mark one strike against a transport. */
1591 sctp_do_8_2_transport_strike(commands, asoc,
1592 cmd->obj.transport, 0);
1593 break;
1594
1595 case SCTP_CMD_TRANSPORT_IDLE:
1596 t = cmd->obj.transport;
1597 sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE);
1598 break;
1599
1600 case SCTP_CMD_TRANSPORT_HB_SENT:
1601 t = cmd->obj.transport;
1602 sctp_do_8_2_transport_strike(commands, asoc,
1603 t, 1);
1604 t->hb_sent = 1;
1605 break;
1606
1607 case SCTP_CMD_TRANSPORT_ON:
1608 t = cmd->obj.transport;
1609 sctp_cmd_transport_on(commands, asoc, t, chunk);
1610 break;
1611
1612 case SCTP_CMD_HB_TIMERS_START:
1613 sctp_cmd_hb_timers_start(commands, asoc);
1614 break;
1615
1616 case SCTP_CMD_HB_TIMER_UPDATE:
1617 t = cmd->obj.transport;
1618 sctp_cmd_hb_timer_update(commands, t);
1619 break;
1620
1621 case SCTP_CMD_HB_TIMERS_STOP:
1622 sctp_cmd_hb_timers_stop(commands, asoc);
1623 break;
1624
1625 case SCTP_CMD_REPORT_ERROR:
1626 error = cmd->obj.error;
1627 break;
1628
1629 case SCTP_CMD_PROCESS_CTSN:
1630 /* Dummy up a SACK for processing. */
1631 sackh.cum_tsn_ack = cmd->obj.be32;
1632 sackh.a_rwnd = asoc->peer.rwnd +
1633 asoc->outqueue.outstanding_bytes;
1634 sackh.num_gap_ack_blocks = 0;
1635 sackh.num_dup_tsns = 0;
1636 chunk->subh.sack_hdr = &sackh;
1637 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK,
1638 SCTP_CHUNK(chunk));
1639 break;
1640
1641 case SCTP_CMD_DISCARD_PACKET:
1642 /* We need to discard the whole packet.
1643 * Uncork the queue since there might be
1644 * responses pending
1645 */
1646 chunk->pdiscard = 1;
1647 if (asoc) {
1648 sctp_outq_uncork(&asoc->outqueue);
1649 local_cork = 0;
1650 }
1651 break;
1652
1653 case SCTP_CMD_RTO_PENDING:
1654 t = cmd->obj.transport;
1655 t->rto_pending = 1;
1656 break;
1657
1658 case SCTP_CMD_PART_DELIVER:
1659 sctp_ulpq_partial_delivery(&asoc->ulpq, GFP_ATOMIC);
1660 break;
1661
1662 case SCTP_CMD_RENEGE:
1663 sctp_ulpq_renege(&asoc->ulpq, cmd->obj.chunk,
1664 GFP_ATOMIC);
1665 break;
1666
1667 case SCTP_CMD_SETUP_T4:
1668 sctp_cmd_setup_t4(commands, asoc, cmd->obj.chunk);
1669 break;
1670
1671 case SCTP_CMD_PROCESS_OPERR:
1672 sctp_cmd_process_operr(commands, asoc, chunk);
1673 break;
1674 case SCTP_CMD_CLEAR_INIT_TAG:
1675 asoc->peer.i.init_tag = 0;
1676 break;
1677 case SCTP_CMD_DEL_NON_PRIMARY:
1678 sctp_cmd_del_non_primary(asoc);
1679 break;
1680 case SCTP_CMD_T3_RTX_TIMERS_STOP:
1681 sctp_cmd_t3_rtx_timers_stop(commands, asoc);
1682 break;
1683 case SCTP_CMD_FORCE_PRIM_RETRAN:
1684 t = asoc->peer.retran_path;
1685 asoc->peer.retran_path = asoc->peer.primary_path;
1686 error = sctp_outq_uncork(&asoc->outqueue);
1687 local_cork = 0;
1688 asoc->peer.retran_path = t;
1689 break;
1690 case SCTP_CMD_SET_SK_ERR:
1691 sctp_cmd_set_sk_err(asoc, cmd->obj.error);
1692 break;
1693 case SCTP_CMD_ASSOC_CHANGE:
1694 sctp_cmd_assoc_change(commands, asoc,
1695 cmd->obj.u8);
1696 break;
1697 case SCTP_CMD_ADAPTATION_IND:
1698 sctp_cmd_adaptation_ind(commands, asoc);
1699 break;
1700
1701 case SCTP_CMD_ASSOC_SHKEY:
1702 error = sctp_auth_asoc_init_active_key(asoc,
1703 GFP_ATOMIC);
1704 break;
1705 case SCTP_CMD_UPDATE_INITTAG:
1706 asoc->peer.i.init_tag = cmd->obj.u32;
1707 break;
1708 case SCTP_CMD_SEND_MSG:
1709 if (!asoc->outqueue.cork) {
1710 sctp_outq_cork(&asoc->outqueue);
1711 local_cork = 1;
1712 }
1713 error = sctp_cmd_send_msg(asoc, cmd->obj.msg);
1714 break;
1715 case SCTP_CMD_SEND_NEXT_ASCONF:
1716 sctp_cmd_send_asconf(asoc);
1717 break;
1718 case SCTP_CMD_PURGE_ASCONF_QUEUE:
1719 sctp_asconf_queue_teardown(asoc);
1720 break;
1721
1722 case SCTP_CMD_SET_ASOC:
1723 asoc = cmd->obj.asoc;
1724 break;
1725
1726 default:
1727 pr_warn("Impossible command: %u\n",
1728 cmd->verb);
1729 break;
1730 }
1731
1732 if (error)
1733 break;
1734 }
1735
1736 out:
1737 /* If this is in response to a received chunk, wait until
1738 * we are done with the packet to open the queue so that we don't
1739 * send multiple packets in response to a single request.
1740 */
1741 if (asoc && SCTP_EVENT_T_CHUNK == event_type && chunk) {
1742 if (chunk->end_of_packet || chunk->singleton)
1743 error = sctp_outq_uncork(&asoc->outqueue);
1744 } else if (local_cork)
1745 error = sctp_outq_uncork(&asoc->outqueue);
1746 return error;
1747 nomem:
1748 error = -ENOMEM;
1749 goto out;
1750 }
1751
Linux with added FPC-III support