1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* SCTP kernel implementation
3 * (C) Copyright IBM Corp. 2001, 2004
4 * Copyright (c) 1999 Cisco, Inc.
5 * Copyright (c) 1999-2001 Motorola, Inc.
6 *
7 * This file is part of the SCTP kernel implementation
8 *
9 * These functions work with the state functions in sctp_sm_statefuns.c
10 * to implement that state operations. These functions implement the
11 * steps which require modifying existing data structures.
12 *
13 * Please send any bug reports or fixes you make to the
14 * email address(es):
15 * lksctp developers <linux-sctp@vger.kernel.org>
16 *
17 * Written or modified by:
18 * La Monte H.P. Yarroll <piggy@acm.org>
19 * Karl Knutson <karl@athena.chicago.il.us>
20 * Jon Grimm <jgrimm@austin.ibm.com>
21 * Hui Huang <hui.huang@nokia.com>
22 * Dajiang Zhang <dajiang.zhang@nokia.com>
23 * Daisy Chang <daisyc@us.ibm.com>
24 * Sridhar Samudrala <sri@us.ibm.com>
25 * Ardelle Fan <ardelle.fan@intel.com>
26 */
27
28 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
29
30 #include <linux/skbuff.h>
31 #include <linux/types.h>
32 #include <linux/socket.h>
33 #include <linux/ip.h>
34 #include <linux/gfp.h>
35 #include <net/sock.h>
36 #include <net/sctp/sctp.h>
37 #include <net/sctp/sm.h>
38 #include <net/sctp/stream_sched.h>
39
40 static int sctp_cmd_interpreter(enum sctp_event_type event_type,
41 union sctp_subtype subtype,
42 enum sctp_state state,
43 struct sctp_endpoint *ep,
44 struct sctp_association *asoc,
45 void *event_arg,
46 enum sctp_disposition status,
47 struct sctp_cmd_seq *commands,
48 gfp_t gfp);
49 static int sctp_side_effects(enum sctp_event_type event_type,
50 union sctp_subtype subtype,
51 enum sctp_state state,
52 struct sctp_endpoint *ep,
53 struct sctp_association **asoc,
54 void *event_arg,
55 enum sctp_disposition status,
56 struct sctp_cmd_seq *commands,
57 gfp_t gfp);
58
59 /********************************************************************
60 * Helper functions
61 ********************************************************************/
62
63 /* A helper function for delayed processing of INET ECN CE bit. */
sctp_do_ecn_ce_work(struct sctp_association * asoc,__u32 lowest_tsn)64 static void sctp_do_ecn_ce_work(struct sctp_association *asoc,
65 __u32 lowest_tsn)
66 {
67 /* Save the TSN away for comparison when we receive CWR */
68
69 asoc->last_ecne_tsn = lowest_tsn;
70 asoc->need_ecne = 1;
71 }
72
73 /* Helper function for delayed processing of SCTP ECNE chunk. */
74 /* RFC 2960 Appendix A
75 *
76 * RFC 2481 details a specific bit for a sender to send in
77 * the header of its next outbound TCP segment to indicate to
78 * its peer that it has reduced its congestion window. This
79 * is termed the CWR bit. For SCTP the same indication is made
80 * by including the CWR chunk. This chunk contains one data
81 * element, i.e. the TSN number that was sent in the ECNE chunk.
82 * This element represents the lowest TSN number in the datagram
83 * that was originally marked with the CE bit.
84 */
sctp_do_ecn_ecne_work(struct sctp_association * asoc,__u32 lowest_tsn,struct sctp_chunk * chunk)85 static struct sctp_chunk *sctp_do_ecn_ecne_work(struct sctp_association *asoc,
86 __u32 lowest_tsn,
87 struct sctp_chunk *chunk)
88 {
89 struct sctp_chunk *repl;
90
91 /* Our previously transmitted packet ran into some congestion
92 * so we should take action by reducing cwnd and ssthresh
93 * and then ACK our peer that we we've done so by
94 * sending a CWR.
95 */
96
97 /* First, try to determine if we want to actually lower
98 * our cwnd variables. Only lower them if the ECNE looks more
99 * recent than the last response.
100 */
101 if (TSN_lt(asoc->last_cwr_tsn, lowest_tsn)) {
102 struct sctp_transport *transport;
103
104 /* Find which transport's congestion variables
105 * need to be adjusted.
106 */
107 transport = sctp_assoc_lookup_tsn(asoc, lowest_tsn);
108
109 /* Update the congestion variables. */
110 if (transport)
111 sctp_transport_lower_cwnd(transport,
112 SCTP_LOWER_CWND_ECNE);
113 asoc->last_cwr_tsn = lowest_tsn;
114 }
115
116 /* Always try to quiet the other end. In case of lost CWR,
117 * resend last_cwr_tsn.
118 */
119 repl = sctp_make_cwr(asoc, asoc->last_cwr_tsn, chunk);
120
121 /* If we run out of memory, it will look like a lost CWR. We'll
122 * get back in sync eventually.
123 */
124 return repl;
125 }
126
127 /* Helper function to do delayed processing of ECN CWR chunk. */
sctp_do_ecn_cwr_work(struct sctp_association * asoc,__u32 lowest_tsn)128 static void sctp_do_ecn_cwr_work(struct sctp_association *asoc,
129 __u32 lowest_tsn)
130 {
131 /* Turn off ECNE getting auto-prepended to every outgoing
132 * packet
133 */
134 asoc->need_ecne = 0;
135 }
136
137 /* Generate SACK if necessary. We call this at the end of a packet. */
sctp_gen_sack(struct sctp_association * asoc,int force,struct sctp_cmd_seq * commands)138 static int sctp_gen_sack(struct sctp_association *asoc, int force,
139 struct sctp_cmd_seq *commands)
140 {
141 struct sctp_transport *trans = asoc->peer.last_data_from;
142 __u32 ctsn, max_tsn_seen;
143 struct sctp_chunk *sack;
144 int error = 0;
145
146 if (force ||
147 (!trans && (asoc->param_flags & SPP_SACKDELAY_DISABLE)) ||
148 (trans && (trans->param_flags & SPP_SACKDELAY_DISABLE)))
149 asoc->peer.sack_needed = 1;
150
151 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
152 max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
153
154 /* From 12.2 Parameters necessary per association (i.e. the TCB):
155 *
156 * Ack State : This flag indicates if the next received packet
157 * : is to be responded to with a SACK. ...
158 * : When DATA chunks are out of order, SACK's
159 * : are not delayed (see Section 6).
160 *
161 * [This is actually not mentioned in Section 6, but we
162 * implement it here anyway. --piggy]
163 */
164 if (max_tsn_seen != ctsn)
165 asoc->peer.sack_needed = 1;
166
167 /* From 6.2 Acknowledgement on Reception of DATA Chunks:
168 *
169 * Section 4.2 of [RFC2581] SHOULD be followed. Specifically,
170 * an acknowledgement SHOULD be generated for at least every
171 * second packet (not every second DATA chunk) received, and
172 * SHOULD be generated within 200 ms of the arrival of any
173 * unacknowledged DATA chunk. ...
174 */
175 if (!asoc->peer.sack_needed) {
176 asoc->peer.sack_cnt++;
177
178 /* Set the SACK delay timeout based on the
179 * SACK delay for the last transport
180 * data was received from, or the default
181 * for the association.
182 */
183 if (trans) {
184 /* We will need a SACK for the next packet. */
185 if (asoc->peer.sack_cnt >= trans->sackfreq - 1)
186 asoc->peer.sack_needed = 1;
187
188 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
189 trans->sackdelay;
190 } else {
191 /* We will need a SACK for the next packet. */
192 if (asoc->peer.sack_cnt >= asoc->sackfreq - 1)
193 asoc->peer.sack_needed = 1;
194
195 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
196 asoc->sackdelay;
197 }
198
199 /* Restart the SACK timer. */
200 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
201 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
202 } else {
203 __u32 old_a_rwnd = asoc->a_rwnd;
204
205 asoc->a_rwnd = asoc->rwnd;
206 sack = sctp_make_sack(asoc);
207 if (!sack) {
208 asoc->a_rwnd = old_a_rwnd;
209 goto nomem;
210 }
211
212 asoc->peer.sack_needed = 0;
213 asoc->peer.sack_cnt = 0;
214
215 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(sack));
216
217 /* Stop the SACK timer. */
218 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
219 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
220 }
221
222 return error;
223 nomem:
224 error = -ENOMEM;
225 return error;
226 }
227
228 /* When the T3-RTX timer expires, it calls this function to create the
229 * relevant state machine event.
230 */
sctp_generate_t3_rtx_event(struct timer_list * t)231 void sctp_generate_t3_rtx_event(struct timer_list *t)
232 {
233 struct sctp_transport *transport =
234 from_timer(transport, t, T3_rtx_timer);
235 struct sctp_association *asoc = transport->asoc;
236 struct sock *sk = asoc->base.sk;
237 struct net *net = sock_net(sk);
238 int error;
239
240 /* Check whether a task is in the sock. */
241
242 bh_lock_sock(sk);
243 if (sock_owned_by_user(sk)) {
244 pr_debug("%s: sock is busy\n", __func__);
245
246 /* Try again later. */
247 if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20)))
248 sctp_transport_hold(transport);
249 goto out_unlock;
250 }
251
252 /* Run through the state machine. */
253 error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
254 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX),
255 asoc->state,
256 asoc->ep, asoc,
257 transport, GFP_ATOMIC);
258
259 if (error)
260 sk->sk_err = -error;
261
262 out_unlock:
263 bh_unlock_sock(sk);
264 sctp_transport_put(transport);
265 }
266
267 /* This is a sa interface for producing timeout events. It works
268 * for timeouts which use the association as their parameter.
269 */
sctp_generate_timeout_event(struct sctp_association * asoc,enum sctp_event_timeout timeout_type)270 static void sctp_generate_timeout_event(struct sctp_association *asoc,
271 enum sctp_event_timeout timeout_type)
272 {
273 struct sock *sk = asoc->base.sk;
274 struct net *net = sock_net(sk);
275 int error = 0;
276
277 bh_lock_sock(sk);
278 if (sock_owned_by_user(sk)) {
279 pr_debug("%s: sock is busy: timer %d\n", __func__,
280 timeout_type);
281
282 /* Try again later. */
283 if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20)))
284 sctp_association_hold(asoc);
285 goto out_unlock;
286 }
287
288 /* Is this association really dead and just waiting around for
289 * the timer to let go of the reference?
290 */
291 if (asoc->base.dead)
292 goto out_unlock;
293
294 /* Run through the state machine. */
295 error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
296 SCTP_ST_TIMEOUT(timeout_type),
297 asoc->state, asoc->ep, asoc,
298 (void *)timeout_type, GFP_ATOMIC);
299
300 if (error)
301 sk->sk_err = -error;
302
303 out_unlock:
304 bh_unlock_sock(sk);
305 sctp_association_put(asoc);
306 }
307
sctp_generate_t1_cookie_event(struct timer_list * t)308 static void sctp_generate_t1_cookie_event(struct timer_list *t)
309 {
310 struct sctp_association *asoc =
311 from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_T1_COOKIE]);
312
313 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE);
314 }
315
sctp_generate_t1_init_event(struct timer_list * t)316 static void sctp_generate_t1_init_event(struct timer_list *t)
317 {
318 struct sctp_association *asoc =
319 from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_T1_INIT]);
320
321 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT);
322 }
323
sctp_generate_t2_shutdown_event(struct timer_list * t)324 static void sctp_generate_t2_shutdown_event(struct timer_list *t)
325 {
326 struct sctp_association *asoc =
327 from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN]);
328
329 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN);
330 }
331
sctp_generate_t4_rto_event(struct timer_list * t)332 static void sctp_generate_t4_rto_event(struct timer_list *t)
333 {
334 struct sctp_association *asoc =
335 from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_T4_RTO]);
336
337 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO);
338 }
339
sctp_generate_t5_shutdown_guard_event(struct timer_list * t)340 static void sctp_generate_t5_shutdown_guard_event(struct timer_list *t)
341 {
342 struct sctp_association *asoc =
343 from_timer(asoc, t,
344 timers[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD]);
345
346 sctp_generate_timeout_event(asoc,
347 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD);
348
349 } /* sctp_generate_t5_shutdown_guard_event() */
350
sctp_generate_autoclose_event(struct timer_list * t)351 static void sctp_generate_autoclose_event(struct timer_list *t)
352 {
353 struct sctp_association *asoc =
354 from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_AUTOCLOSE]);
355
356 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE);
357 }
358
359 /* Generate a heart beat event. If the sock is busy, reschedule. Make
360 * sure that the transport is still valid.
361 */
sctp_generate_heartbeat_event(struct timer_list * t)362 void sctp_generate_heartbeat_event(struct timer_list *t)
363 {
364 struct sctp_transport *transport = from_timer(transport, t, hb_timer);
365 struct sctp_association *asoc = transport->asoc;
366 struct sock *sk = asoc->base.sk;
367 struct net *net = sock_net(sk);
368 u32 elapsed, timeout;
369 int error = 0;
370
371 bh_lock_sock(sk);
372 if (sock_owned_by_user(sk)) {
373 pr_debug("%s: sock is busy\n", __func__);
374
375 /* Try again later. */
376 if (!mod_timer(&transport->hb_timer, jiffies + (HZ/20)))
377 sctp_transport_hold(transport);
378 goto out_unlock;
379 }
380
381 /* Check if we should still send the heartbeat or reschedule */
382 elapsed = jiffies - transport->last_time_sent;
383 timeout = sctp_transport_timeout(transport);
384 if (elapsed < timeout) {
385 elapsed = timeout - elapsed;
386 if (!mod_timer(&transport->hb_timer, jiffies + elapsed))
387 sctp_transport_hold(transport);
388 goto out_unlock;
389 }
390
391 error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
392 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT),
393 asoc->state, asoc->ep, asoc,
394 transport, GFP_ATOMIC);
395
396 if (error)
397 sk->sk_err = -error;
398
399 out_unlock:
400 bh_unlock_sock(sk);
401 sctp_transport_put(transport);
402 }
403
404 /* Handle the timeout of the ICMP protocol unreachable timer. Trigger
405 * the correct state machine transition that will close the association.
406 */
sctp_generate_proto_unreach_event(struct timer_list * t)407 void sctp_generate_proto_unreach_event(struct timer_list *t)
408 {
409 struct sctp_transport *transport =
410 from_timer(transport, t, proto_unreach_timer);
411 struct sctp_association *asoc = transport->asoc;
412 struct sock *sk = asoc->base.sk;
413 struct net *net = sock_net(sk);
414
415 bh_lock_sock(sk);
416 if (sock_owned_by_user(sk)) {
417 pr_debug("%s: sock is busy\n", __func__);
418
419 /* Try again later. */
420 if (!mod_timer(&transport->proto_unreach_timer,
421 jiffies + (HZ/20)))
422 sctp_transport_hold(transport);
423 goto out_unlock;
424 }
425
426 /* Is this structure just waiting around for us to actually
427 * get destroyed?
428 */
429 if (asoc->base.dead)
430 goto out_unlock;
431
432 sctp_do_sm(net, SCTP_EVENT_T_OTHER,
433 SCTP_ST_OTHER(SCTP_EVENT_ICMP_PROTO_UNREACH),
434 asoc->state, asoc->ep, asoc, transport, GFP_ATOMIC);
435
436 out_unlock:
437 bh_unlock_sock(sk);
438 sctp_transport_put(transport);
439 }
440
441 /* Handle the timeout of the RE-CONFIG timer. */
sctp_generate_reconf_event(struct timer_list * t)442 void sctp_generate_reconf_event(struct timer_list *t)
443 {
444 struct sctp_transport *transport =
445 from_timer(transport, t, reconf_timer);
446 struct sctp_association *asoc = transport->asoc;
447 struct sock *sk = asoc->base.sk;
448 struct net *net = sock_net(sk);
449 int error = 0;
450
451 bh_lock_sock(sk);
452 if (sock_owned_by_user(sk)) {
453 pr_debug("%s: sock is busy\n", __func__);
454
455 /* Try again later. */
456 if (!mod_timer(&transport->reconf_timer, jiffies + (HZ / 20)))
457 sctp_transport_hold(transport);
458 goto out_unlock;
459 }
460
461 /* This happens when the response arrives after the timer is triggered. */
462 if (!asoc->strreset_chunk)
463 goto out_unlock;
464
465 error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
466 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_RECONF),
467 asoc->state, asoc->ep, asoc,
468 transport, GFP_ATOMIC);
469
470 if (error)
471 sk->sk_err = -error;
472
473 out_unlock:
474 bh_unlock_sock(sk);
475 sctp_transport_put(transport);
476 }
477
478 /* Inject a SACK Timeout event into the state machine. */
sctp_generate_sack_event(struct timer_list * t)479 static void sctp_generate_sack_event(struct timer_list *t)
480 {
481 struct sctp_association *asoc =
482 from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_SACK]);
483
484 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK);
485 }
486
487 sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = {
488 [SCTP_EVENT_TIMEOUT_NONE] = NULL,
489 [SCTP_EVENT_TIMEOUT_T1_COOKIE] = sctp_generate_t1_cookie_event,
490 [SCTP_EVENT_TIMEOUT_T1_INIT] = sctp_generate_t1_init_event,
491 [SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = sctp_generate_t2_shutdown_event,
492 [SCTP_EVENT_TIMEOUT_T3_RTX] = NULL,
493 [SCTP_EVENT_TIMEOUT_T4_RTO] = sctp_generate_t4_rto_event,
494 [SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD] =
495 sctp_generate_t5_shutdown_guard_event,
496 [SCTP_EVENT_TIMEOUT_HEARTBEAT] = NULL,
497 [SCTP_EVENT_TIMEOUT_RECONF] = NULL,
498 [SCTP_EVENT_TIMEOUT_SACK] = sctp_generate_sack_event,
499 [SCTP_EVENT_TIMEOUT_AUTOCLOSE] = sctp_generate_autoclose_event,
500 };
501
502
503 /* RFC 2960 8.2 Path Failure Detection
504 *
505 * When its peer endpoint is multi-homed, an endpoint should keep a
506 * error counter for each of the destination transport addresses of the
507 * peer endpoint.
508 *
509 * Each time the T3-rtx timer expires on any address, or when a
510 * HEARTBEAT sent to an idle address is not acknowledged within a RTO,
511 * the error counter of that destination address will be incremented.
512 * When the value in the error counter exceeds the protocol parameter
513 * 'Path.Max.Retrans' of that destination address, the endpoint should
514 * mark the destination transport address as inactive, and a
515 * notification SHOULD be sent to the upper layer.
516 *
517 */
sctp_do_8_2_transport_strike(struct sctp_cmd_seq * commands,struct sctp_association * asoc,struct sctp_transport * transport,int is_hb)518 static void sctp_do_8_2_transport_strike(struct sctp_cmd_seq *commands,
519 struct sctp_association *asoc,
520 struct sctp_transport *transport,
521 int is_hb)
522 {
523 struct net *net = sock_net(asoc->base.sk);
524
525 /* The check for association's overall error counter exceeding the
526 * threshold is done in the state function.
527 */
528 /* We are here due to a timer expiration. If the timer was
529 * not a HEARTBEAT, then normal error tracking is done.
530 * If the timer was a heartbeat, we only increment error counts
531 * when we already have an outstanding HEARTBEAT that has not
532 * been acknowledged.
533 * Additionally, some tranport states inhibit error increments.
534 */
535 if (!is_hb) {
536 asoc->overall_error_count++;
537 if (transport->state != SCTP_INACTIVE)
538 transport->error_count++;
539 } else if (transport->hb_sent) {
540 if (transport->state != SCTP_UNCONFIRMED)
541 asoc->overall_error_count++;
542 if (transport->state != SCTP_INACTIVE)
543 transport->error_count++;
544 }
545
546 /* If the transport error count is greater than the pf_retrans
547 * threshold, and less than pathmaxrtx, and if the current state
548 * is SCTP_ACTIVE, then mark this transport as Partially Failed,
549 * see SCTP Quick Failover Draft, section 5.1
550 */
551 if (net->sctp.pf_enable &&
552 (transport->state == SCTP_ACTIVE) &&
553 (transport->error_count < transport->pathmaxrxt) &&
554 (transport->error_count > transport->pf_retrans)) {
555
556 sctp_assoc_control_transport(asoc, transport,
557 SCTP_TRANSPORT_PF,
558 0);
559
560 /* Update the hb timer to resend a heartbeat every rto */
561 sctp_transport_reset_hb_timer(transport);
562 }
563
564 if (transport->state != SCTP_INACTIVE &&
565 (transport->error_count > transport->pathmaxrxt)) {
566 pr_debug("%s: association:%p transport addr:%pISpc failed\n",
567 __func__, asoc, &transport->ipaddr.sa);
568
569 sctp_assoc_control_transport(asoc, transport,
570 SCTP_TRANSPORT_DOWN,
571 SCTP_FAILED_THRESHOLD);
572 }
573
574 /* E2) For the destination address for which the timer
575 * expires, set RTO <- RTO * 2 ("back off the timer"). The
576 * maximum value discussed in rule C7 above (RTO.max) may be
577 * used to provide an upper bound to this doubling operation.
578 *
579 * Special Case: the first HB doesn't trigger exponential backoff.
580 * The first unacknowledged HB triggers it. We do this with a flag
581 * that indicates that we have an outstanding HB.
582 */
583 if (!is_hb || transport->hb_sent) {
584 transport->rto = min((transport->rto * 2), transport->asoc->rto_max);
585 sctp_max_rto(asoc, transport);
586 }
587 }
588
589 /* Worker routine to handle INIT command failure. */
sctp_cmd_init_failed(struct sctp_cmd_seq * commands,struct sctp_association * asoc,unsigned int error)590 static void sctp_cmd_init_failed(struct sctp_cmd_seq *commands,
591 struct sctp_association *asoc,
592 unsigned int error)
593 {
594 struct sctp_ulpevent *event;
595
596 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_CANT_STR_ASSOC,
597 (__u16)error, 0, 0, NULL,
598 GFP_ATOMIC);
599
600 if (event)
601 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
602 SCTP_ULPEVENT(event));
603
604 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
605 SCTP_STATE(SCTP_STATE_CLOSED));
606
607 /* SEND_FAILED sent later when cleaning up the association. */
608 asoc->outqueue.error = error;
609 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
610 }
611
612 /* Worker routine to handle SCTP_CMD_ASSOC_FAILED. */
sctp_cmd_assoc_failed(struct sctp_cmd_seq * commands,struct sctp_association * asoc,enum sctp_event_type event_type,union sctp_subtype subtype,struct sctp_chunk * chunk,unsigned int error)613 static void sctp_cmd_assoc_failed(struct sctp_cmd_seq *commands,
614 struct sctp_association *asoc,
615 enum sctp_event_type event_type,
616 union sctp_subtype subtype,
617 struct sctp_chunk *chunk,
618 unsigned int error)
619 {
620 struct sctp_ulpevent *event;
621 struct sctp_chunk *abort;
622
623 /* Cancel any partial delivery in progress. */
624 asoc->stream.si->abort_pd(&asoc->ulpq, GFP_ATOMIC);
625
626 if (event_type == SCTP_EVENT_T_CHUNK && subtype.chunk == SCTP_CID_ABORT)
627 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
628 (__u16)error, 0, 0, chunk,
629 GFP_ATOMIC);
630 else
631 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
632 (__u16)error, 0, 0, NULL,
633 GFP_ATOMIC);
634 if (event)
635 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
636 SCTP_ULPEVENT(event));
637
638 if (asoc->overall_error_count >= asoc->max_retrans) {
639 abort = sctp_make_violation_max_retrans(asoc, chunk);
640 if (abort)
641 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
642 SCTP_CHUNK(abort));
643 }
644
645 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
646 SCTP_STATE(SCTP_STATE_CLOSED));
647
648 /* SEND_FAILED sent later when cleaning up the association. */
649 asoc->outqueue.error = error;
650 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
651 }
652
653 /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT
654 * inside the cookie. In reality, this is only used for INIT-ACK processing
655 * since all other cases use "temporary" associations and can do all
656 * their work in statefuns directly.
657 */
sctp_cmd_process_init(struct sctp_cmd_seq * commands,struct sctp_association * asoc,struct sctp_chunk * chunk,struct sctp_init_chunk * peer_init,gfp_t gfp)658 static int sctp_cmd_process_init(struct sctp_cmd_seq *commands,
659 struct sctp_association *asoc,
660 struct sctp_chunk *chunk,
661 struct sctp_init_chunk *peer_init,
662 gfp_t gfp)
663 {
664 int error;
665
666 /* We only process the init as a sideeffect in a single
667 * case. This is when we process the INIT-ACK. If we
668 * fail during INIT processing (due to malloc problems),
669 * just return the error and stop processing the stack.
670 */
671 if (!sctp_process_init(asoc, chunk, sctp_source(chunk), peer_init, gfp))
672 error = -ENOMEM;
673 else
674 error = 0;
675
676 return error;
677 }
678
679 /* Helper function to break out starting up of heartbeat timers. */
sctp_cmd_hb_timers_start(struct sctp_cmd_seq * cmds,struct sctp_association * asoc)680 static void sctp_cmd_hb_timers_start(struct sctp_cmd_seq *cmds,
681 struct sctp_association *asoc)
682 {
683 struct sctp_transport *t;
684
685 /* Start a heartbeat timer for each transport on the association.
686 * hold a reference on the transport to make sure none of
687 * the needed data structures go away.
688 */
689 list_for_each_entry(t, &asoc->peer.transport_addr_list, transports)
690 sctp_transport_reset_hb_timer(t);
691 }
692
sctp_cmd_hb_timers_stop(struct sctp_cmd_seq * cmds,struct sctp_association * asoc)693 static void sctp_cmd_hb_timers_stop(struct sctp_cmd_seq *cmds,
694 struct sctp_association *asoc)
695 {
696 struct sctp_transport *t;
697
698 /* Stop all heartbeat timers. */
699
700 list_for_each_entry(t, &asoc->peer.transport_addr_list,
701 transports) {
702 if (del_timer(&t->hb_timer))
703 sctp_transport_put(t);
704 }
705 }
706
707 /* Helper function to stop any pending T3-RTX timers */
sctp_cmd_t3_rtx_timers_stop(struct sctp_cmd_seq * cmds,struct sctp_association * asoc)708 static void sctp_cmd_t3_rtx_timers_stop(struct sctp_cmd_seq *cmds,
709 struct sctp_association *asoc)
710 {
711 struct sctp_transport *t;
712
713 list_for_each_entry(t, &asoc->peer.transport_addr_list,
714 transports) {
715 if (del_timer(&t->T3_rtx_timer))
716 sctp_transport_put(t);
717 }
718 }
719
720
721 /* Helper function to handle the reception of an HEARTBEAT ACK. */
sctp_cmd_transport_on(struct sctp_cmd_seq * cmds,struct sctp_association * asoc,struct sctp_transport * t,struct sctp_chunk * chunk)722 static void sctp_cmd_transport_on(struct sctp_cmd_seq *cmds,
723 struct sctp_association *asoc,
724 struct sctp_transport *t,
725 struct sctp_chunk *chunk)
726 {
727 struct sctp_sender_hb_info *hbinfo;
728 int was_unconfirmed = 0;
729
730 /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the
731 * HEARTBEAT should clear the error counter of the destination
732 * transport address to which the HEARTBEAT was sent.
733 */
734 t->error_count = 0;
735
736 /*
737 * Although RFC4960 specifies that the overall error count must
738 * be cleared when a HEARTBEAT ACK is received, we make an
739 * exception while in SHUTDOWN PENDING. If the peer keeps its
740 * window shut forever, we may never be able to transmit our
741 * outstanding data and rely on the retransmission limit be reached
742 * to shutdown the association.
743 */
744 if (t->asoc->state < SCTP_STATE_SHUTDOWN_PENDING)
745 t->asoc->overall_error_count = 0;
746
747 /* Clear the hb_sent flag to signal that we had a good
748 * acknowledgement.
749 */
750 t->hb_sent = 0;
751
752 /* Mark the destination transport address as active if it is not so
753 * marked.
754 */
755 if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED)) {
756 was_unconfirmed = 1;
757 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
758 SCTP_HEARTBEAT_SUCCESS);
759 }
760
761 if (t->state == SCTP_PF)
762 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
763 SCTP_HEARTBEAT_SUCCESS);
764
765 /* HB-ACK was received for a the proper HB. Consider this
766 * forward progress.
767 */
768 if (t->dst)
769 sctp_transport_dst_confirm(t);
770
771 /* The receiver of the HEARTBEAT ACK should also perform an
772 * RTT measurement for that destination transport address
773 * using the time value carried in the HEARTBEAT ACK chunk.
774 * If the transport's rto_pending variable has been cleared,
775 * it was most likely due to a retransmit. However, we want
776 * to re-enable it to properly update the rto.
777 */
778 if (t->rto_pending == 0)
779 t->rto_pending = 1;
780
781 hbinfo = (struct sctp_sender_hb_info *)chunk->skb->data;
782 sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at));
783
784 /* Update the heartbeat timer. */
785 sctp_transport_reset_hb_timer(t);
786
787 if (was_unconfirmed && asoc->peer.transport_count == 1)
788 sctp_transport_immediate_rtx(t);
789 }
790
791
792 /* Helper function to process the process SACK command. */
sctp_cmd_process_sack(struct sctp_cmd_seq * cmds,struct sctp_association * asoc,struct sctp_chunk * chunk)793 static int sctp_cmd_process_sack(struct sctp_cmd_seq *cmds,
794 struct sctp_association *asoc,
795 struct sctp_chunk *chunk)
796 {
797 int err = 0;
798
799 if (sctp_outq_sack(&asoc->outqueue, chunk)) {
800 struct net *net = sock_net(asoc->base.sk);
801
802 /* There are no more TSNs awaiting SACK. */
803 err = sctp_do_sm(net, SCTP_EVENT_T_OTHER,
804 SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN),
805 asoc->state, asoc->ep, asoc, NULL,
806 GFP_ATOMIC);
807 }
808
809 return err;
810 }
811
812 /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set
813 * the transport for a shutdown chunk.
814 */
sctp_cmd_setup_t2(struct sctp_cmd_seq * cmds,struct sctp_association * asoc,struct sctp_chunk * chunk)815 static void sctp_cmd_setup_t2(struct sctp_cmd_seq *cmds,
816 struct sctp_association *asoc,
817 struct sctp_chunk *chunk)
818 {
819 struct sctp_transport *t;
820
821 if (chunk->transport)
822 t = chunk->transport;
823 else {
824 t = sctp_assoc_choose_alter_transport(asoc,
825 asoc->shutdown_last_sent_to);
826 chunk->transport = t;
827 }
828 asoc->shutdown_last_sent_to = t;
829 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto;
830 }
831
sctp_cmd_assoc_update(struct sctp_cmd_seq * cmds,struct sctp_association * asoc,struct sctp_association * new)832 static void sctp_cmd_assoc_update(struct sctp_cmd_seq *cmds,
833 struct sctp_association *asoc,
834 struct sctp_association *new)
835 {
836 struct net *net = sock_net(asoc->base.sk);
837 struct sctp_chunk *abort;
838
839 if (!sctp_assoc_update(asoc, new))
840 return;
841
842 abort = sctp_make_abort(asoc, NULL, sizeof(struct sctp_errhdr));
843 if (abort) {
844 sctp_init_cause(abort, SCTP_ERROR_RSRC_LOW, 0);
845 sctp_add_cmd_sf(cmds, SCTP_CMD_REPLY, SCTP_CHUNK(abort));
846 }
847 sctp_add_cmd_sf(cmds, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(ECONNABORTED));
848 sctp_add_cmd_sf(cmds, SCTP_CMD_ASSOC_FAILED,
849 SCTP_PERR(SCTP_ERROR_RSRC_LOW));
850 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
851 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
852 }
853
854 /* Helper function to change the state of an association. */
sctp_cmd_new_state(struct sctp_cmd_seq * cmds,struct sctp_association * asoc,enum sctp_state state)855 static void sctp_cmd_new_state(struct sctp_cmd_seq *cmds,
856 struct sctp_association *asoc,
857 enum sctp_state state)
858 {
859 struct sock *sk = asoc->base.sk;
860
861 asoc->state = state;
862
863 pr_debug("%s: asoc:%p[%s]\n", __func__, asoc, sctp_state_tbl[state]);
864
865 if (sctp_style(sk, TCP)) {
866 /* Change the sk->sk_state of a TCP-style socket that has
867 * successfully completed a connect() call.
868 */
869 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED))
870 inet_sk_set_state(sk, SCTP_SS_ESTABLISHED);
871
872 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */
873 if (sctp_state(asoc, SHUTDOWN_RECEIVED) &&
874 sctp_sstate(sk, ESTABLISHED)) {
875 inet_sk_set_state(sk, SCTP_SS_CLOSING);
876 sk->sk_shutdown |= RCV_SHUTDOWN;
877 }
878 }
879
880 if (sctp_state(asoc, COOKIE_WAIT)) {
881 /* Reset init timeouts since they may have been
882 * increased due to timer expirations.
883 */
884 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
885 asoc->rto_initial;
886 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
887 asoc->rto_initial;
888 }
889
890 if (sctp_state(asoc, ESTABLISHED)) {
891 kfree(asoc->peer.cookie);
892 asoc->peer.cookie = NULL;
893 }
894
895 if (sctp_state(asoc, ESTABLISHED) ||
896 sctp_state(asoc, CLOSED) ||
897 sctp_state(asoc, SHUTDOWN_RECEIVED)) {
898 /* Wake up any processes waiting in the asoc's wait queue in
899 * sctp_wait_for_connect() or sctp_wait_for_sndbuf().
900 */
901 if (waitqueue_active(&asoc->wait))
902 wake_up_interruptible(&asoc->wait);
903
904 /* Wake up any processes waiting in the sk's sleep queue of
905 * a TCP-style or UDP-style peeled-off socket in
906 * sctp_wait_for_accept() or sctp_wait_for_packet().
907 * For a UDP-style socket, the waiters are woken up by the
908 * notifications.
909 */
910 if (!sctp_style(sk, UDP))
911 sk->sk_state_change(sk);
912 }
913
914 if (sctp_state(asoc, SHUTDOWN_PENDING) &&
915 !sctp_outq_is_empty(&asoc->outqueue))
916 sctp_outq_uncork(&asoc->outqueue, GFP_ATOMIC);
917 }
918
919 /* Helper function to delete an association. */
sctp_cmd_delete_tcb(struct sctp_cmd_seq * cmds,struct sctp_association * asoc)920 static void sctp_cmd_delete_tcb(struct sctp_cmd_seq *cmds,
921 struct sctp_association *asoc)
922 {
923 struct sock *sk = asoc->base.sk;
924
925 /* If it is a non-temporary association belonging to a TCP-style
926 * listening socket that is not closed, do not free it so that accept()
927 * can pick it up later.
928 */
929 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) &&
930 (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK))
931 return;
932
933 sctp_association_free(asoc);
934 }
935
936 /*
937 * ADDIP Section 4.1 ASCONF Chunk Procedures
938 * A4) Start a T-4 RTO timer, using the RTO value of the selected
939 * destination address (we use active path instead of primary path just
940 * because primary path may be inactive.
941 */
sctp_cmd_setup_t4(struct sctp_cmd_seq * cmds,struct sctp_association * asoc,struct sctp_chunk * chunk)942 static void sctp_cmd_setup_t4(struct sctp_cmd_seq *cmds,
943 struct sctp_association *asoc,
944 struct sctp_chunk *chunk)
945 {
946 struct sctp_transport *t;
947
948 t = sctp_assoc_choose_alter_transport(asoc, chunk->transport);
949 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto;
950 chunk->transport = t;
951 }
952
953 /* Process an incoming Operation Error Chunk. */
sctp_cmd_process_operr(struct sctp_cmd_seq * cmds,struct sctp_association * asoc,struct sctp_chunk * chunk)954 static void sctp_cmd_process_operr(struct sctp_cmd_seq *cmds,
955 struct sctp_association *asoc,
956 struct sctp_chunk *chunk)
957 {
958 struct sctp_errhdr *err_hdr;
959 struct sctp_ulpevent *ev;
960
961 while (chunk->chunk_end > chunk->skb->data) {
962 err_hdr = (struct sctp_errhdr *)(chunk->skb->data);
963
964 ev = sctp_ulpevent_make_remote_error(asoc, chunk, 0,
965 GFP_ATOMIC);
966 if (!ev)
967 return;
968
969 asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
970
971 switch (err_hdr->cause) {
972 case SCTP_ERROR_UNKNOWN_CHUNK:
973 {
974 struct sctp_chunkhdr *unk_chunk_hdr;
975
976 unk_chunk_hdr = (struct sctp_chunkhdr *)
977 err_hdr->variable;
978 switch (unk_chunk_hdr->type) {
979 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with
980 * an ERROR chunk reporting that it did not recognized
981 * the ASCONF chunk type, the sender of the ASCONF MUST
982 * NOT send any further ASCONF chunks and MUST stop its
983 * T-4 timer.
984 */
985 case SCTP_CID_ASCONF:
986 if (asoc->peer.asconf_capable == 0)
987 break;
988
989 asoc->peer.asconf_capable = 0;
990 sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP,
991 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
992 break;
993 default:
994 break;
995 }
996 break;
997 }
998 default:
999 break;
1000 }
1001 }
1002 }
1003
1004 /* Helper function to remove the association non-primary peer
1005 * transports.
1006 */
sctp_cmd_del_non_primary(struct sctp_association * asoc)1007 static void sctp_cmd_del_non_primary(struct sctp_association *asoc)
1008 {
1009 struct sctp_transport *t;
1010 struct list_head *temp;
1011 struct list_head *pos;
1012
1013 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1014 t = list_entry(pos, struct sctp_transport, transports);
1015 if (!sctp_cmp_addr_exact(&t->ipaddr,
1016 &asoc->peer.primary_addr)) {
1017 sctp_assoc_rm_peer(asoc, t);
1018 }
1019 }
1020 }
1021
1022 /* Helper function to set sk_err on a 1-1 style socket. */
sctp_cmd_set_sk_err(struct sctp_association * asoc,int error)1023 static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error)
1024 {
1025 struct sock *sk = asoc->base.sk;
1026
1027 if (!sctp_style(sk, UDP))
1028 sk->sk_err = error;
1029 }
1030
1031 /* Helper function to generate an association change event */
sctp_cmd_assoc_change(struct sctp_cmd_seq * commands,struct sctp_association * asoc,u8 state)1032 static void sctp_cmd_assoc_change(struct sctp_cmd_seq *commands,
1033 struct sctp_association *asoc,
1034 u8 state)
1035 {
1036 struct sctp_ulpevent *ev;
1037
1038 ev = sctp_ulpevent_make_assoc_change(asoc, 0, state, 0,
1039 asoc->c.sinit_num_ostreams,
1040 asoc->c.sinit_max_instreams,
1041 NULL, GFP_ATOMIC);
1042 if (ev)
1043 asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
1044 }
1045
sctp_cmd_peer_no_auth(struct sctp_cmd_seq * commands,struct sctp_association * asoc)1046 static void sctp_cmd_peer_no_auth(struct sctp_cmd_seq *commands,
1047 struct sctp_association *asoc)
1048 {
1049 struct sctp_ulpevent *ev;
1050
1051 ev = sctp_ulpevent_make_authkey(asoc, 0, SCTP_AUTH_NO_AUTH, GFP_ATOMIC);
1052 if (ev)
1053 asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
1054 }
1055
1056 /* Helper function to generate an adaptation indication event */
sctp_cmd_adaptation_ind(struct sctp_cmd_seq * commands,struct sctp_association * asoc)1057 static void sctp_cmd_adaptation_ind(struct sctp_cmd_seq *commands,
1058 struct sctp_association *asoc)
1059 {
1060 struct sctp_ulpevent *ev;
1061
1062 ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC);
1063
1064 if (ev)
1065 asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
1066 }
1067
1068
sctp_cmd_t1_timer_update(struct sctp_association * asoc,enum sctp_event_timeout timer,char * name)1069 static void sctp_cmd_t1_timer_update(struct sctp_association *asoc,
1070 enum sctp_event_timeout timer,
1071 char *name)
1072 {
1073 struct sctp_transport *t;
1074
1075 t = asoc->init_last_sent_to;
1076 asoc->init_err_counter++;
1077
1078 if (t->init_sent_count > (asoc->init_cycle + 1)) {
1079 asoc->timeouts[timer] *= 2;
1080 if (asoc->timeouts[timer] > asoc->max_init_timeo) {
1081 asoc->timeouts[timer] = asoc->max_init_timeo;
1082 }
1083 asoc->init_cycle++;
1084
1085 pr_debug("%s: T1[%s] timeout adjustment init_err_counter:%d"
1086 " cycle:%d timeout:%ld\n", __func__, name,
1087 asoc->init_err_counter, asoc->init_cycle,
1088 asoc->timeouts[timer]);
1089 }
1090
1091 }
1092
1093 /* Send the whole message, chunk by chunk, to the outqueue.
1094 * This way the whole message is queued up and bundling if
1095 * encouraged for small fragments.
1096 */
sctp_cmd_send_msg(struct sctp_association * asoc,struct sctp_datamsg * msg,gfp_t gfp)1097 static void sctp_cmd_send_msg(struct sctp_association *asoc,
1098 struct sctp_datamsg *msg, gfp_t gfp)
1099 {
1100 struct sctp_chunk *chunk;
1101
1102 list_for_each_entry(chunk, &msg->chunks, frag_list)
1103 sctp_outq_tail(&asoc->outqueue, chunk, gfp);
1104
1105 asoc->outqueue.sched->enqueue(&asoc->outqueue, msg);
1106 }
1107
1108
1109 /* These three macros allow us to pull the debugging code out of the
1110 * main flow of sctp_do_sm() to keep attention focused on the real
1111 * functionality there.
1112 */
1113 #define debug_pre_sfn() \
1114 pr_debug("%s[pre-fn]: ep:%p, %s, %s, asoc:%p[%s], %s\n", __func__, \
1115 ep, sctp_evttype_tbl[event_type], (*debug_fn)(subtype), \
1116 asoc, sctp_state_tbl[state], state_fn->name)
1117
1118 #define debug_post_sfn() \
1119 pr_debug("%s[post-fn]: asoc:%p, status:%s\n", __func__, asoc, \
1120 sctp_status_tbl[status])
1121
1122 #define debug_post_sfx() \
1123 pr_debug("%s[post-sfx]: error:%d, asoc:%p[%s]\n", __func__, error, \
1124 asoc, sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \
1125 sctp_assoc2id(asoc))) ? asoc->state : SCTP_STATE_CLOSED])
1126
1127 /*
1128 * This is the master state machine processing function.
1129 *
1130 * If you want to understand all of lksctp, this is a
1131 * good place to start.
1132 */
sctp_do_sm(struct net * net,enum sctp_event_type event_type,union sctp_subtype subtype,enum sctp_state state,struct sctp_endpoint * ep,struct sctp_association * asoc,void * event_arg,gfp_t gfp)1133 int sctp_do_sm(struct net *net, enum sctp_event_type event_type,
1134 union sctp_subtype subtype, enum sctp_state state,
1135 struct sctp_endpoint *ep, struct sctp_association *asoc,
1136 void *event_arg, gfp_t gfp)
1137 {
1138 typedef const char *(printfn_t)(union sctp_subtype);
1139 static printfn_t *table[] = {
1140 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname,
1141 };
1142 printfn_t *debug_fn __attribute__ ((unused)) = table[event_type];
1143 const struct sctp_sm_table_entry *state_fn;
1144 struct sctp_cmd_seq commands;
1145 enum sctp_disposition status;
1146 int error = 0;
1147
1148 /* Look up the state function, run it, and then process the
1149 * side effects. These three steps are the heart of lksctp.
1150 */
1151 state_fn = sctp_sm_lookup_event(net, event_type, state, subtype);
1152
1153 sctp_init_cmd_seq(&commands);
1154
1155 debug_pre_sfn();
1156 status = state_fn->fn(net, ep, asoc, subtype, event_arg, &commands);
1157 debug_post_sfn();
1158
1159 error = sctp_side_effects(event_type, subtype, state,
1160 ep, &asoc, event_arg, status,
1161 &commands, gfp);
1162 debug_post_sfx();
1163
1164 return error;
1165 }
1166
1167 /*****************************************************************
1168 * This the master state function side effect processing function.
1169 *****************************************************************/
sctp_side_effects(enum sctp_event_type event_type,union sctp_subtype subtype,enum sctp_state state,struct sctp_endpoint * ep,struct sctp_association ** asoc,void * event_arg,enum sctp_disposition status,struct sctp_cmd_seq * commands,gfp_t gfp)1170 static int sctp_side_effects(enum sctp_event_type event_type,
1171 union sctp_subtype subtype,
1172 enum sctp_state state,
1173 struct sctp_endpoint *ep,
1174 struct sctp_association **asoc,
1175 void *event_arg,
1176 enum sctp_disposition status,
1177 struct sctp_cmd_seq *commands,
1178 gfp_t gfp)
1179 {
1180 int error;
1181
1182 /* FIXME - Most of the dispositions left today would be categorized
1183 * as "exceptional" dispositions. For those dispositions, it
1184 * may not be proper to run through any of the commands at all.
1185 * For example, the command interpreter might be run only with
1186 * disposition SCTP_DISPOSITION_CONSUME.
1187 */
1188 if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state,
1189 ep, *asoc,
1190 event_arg, status,
1191 commands, gfp)))
1192 goto bail;
1193
1194 switch (status) {
1195 case SCTP_DISPOSITION_DISCARD:
1196 pr_debug("%s: ignored sctp protocol event - state:%d, "
1197 "event_type:%d, event_id:%d\n", __func__, state,
1198 event_type, subtype.chunk);
1199 break;
1200
1201 case SCTP_DISPOSITION_NOMEM:
1202 /* We ran out of memory, so we need to discard this
1203 * packet.
1204 */
1205 /* BUG--we should now recover some memory, probably by
1206 * reneging...
1207 */
1208 error = -ENOMEM;
1209 break;
1210
1211 case SCTP_DISPOSITION_DELETE_TCB:
1212 case SCTP_DISPOSITION_ABORT:
1213 /* This should now be a command. */
1214 *asoc = NULL;
1215 break;
1216
1217 case SCTP_DISPOSITION_CONSUME:
1218 /*
1219 * We should no longer have much work to do here as the
1220 * real work has been done as explicit commands above.
1221 */
1222 break;
1223
1224 case SCTP_DISPOSITION_VIOLATION:
1225 net_err_ratelimited("protocol violation state %d chunkid %d\n",
1226 state, subtype.chunk);
1227 break;
1228
1229 case SCTP_DISPOSITION_NOT_IMPL:
1230 pr_warn("unimplemented feature in state %d, event_type %d, event_id %d\n",
1231 state, event_type, subtype.chunk);
1232 break;
1233
1234 case SCTP_DISPOSITION_BUG:
1235 pr_err("bug in state %d, event_type %d, event_id %d\n",
1236 state, event_type, subtype.chunk);
1237 BUG();
1238 break;
1239
1240 default:
1241 pr_err("impossible disposition %d in state %d, event_type %d, event_id %d\n",
1242 status, state, event_type, subtype.chunk);
1243 error = status;
1244 if (error >= 0)
1245 error = -EINVAL;
1246 WARN_ON_ONCE(1);
1247 break;
1248 }
1249
1250 bail:
1251 return error;
1252 }
1253
1254 /********************************************************************
1255 * 2nd Level Abstractions
1256 ********************************************************************/
1257
1258 /* This is the side-effect interpreter. */
sctp_cmd_interpreter(enum sctp_event_type event_type,union sctp_subtype subtype,enum sctp_state state,struct sctp_endpoint * ep,struct sctp_association * asoc,void * event_arg,enum sctp_disposition status,struct sctp_cmd_seq * commands,gfp_t gfp)1259 static int sctp_cmd_interpreter(enum sctp_event_type event_type,
1260 union sctp_subtype subtype,
1261 enum sctp_state state,
1262 struct sctp_endpoint *ep,
1263 struct sctp_association *asoc,
1264 void *event_arg,
1265 enum sctp_disposition status,
1266 struct sctp_cmd_seq *commands,
1267 gfp_t gfp)
1268 {
1269 struct sctp_sock *sp = sctp_sk(ep->base.sk);
1270 struct sctp_chunk *chunk = NULL, *new_obj;
1271 struct sctp_packet *packet;
1272 struct sctp_sackhdr sackh;
1273 struct timer_list *timer;
1274 struct sctp_transport *t;
1275 unsigned long timeout;
1276 struct sctp_cmd *cmd;
1277 int local_cork = 0;
1278 int error = 0;
1279 int force;
1280
1281 if (SCTP_EVENT_T_TIMEOUT != event_type)
1282 chunk = event_arg;
1283
1284 /* Note: This whole file is a huge candidate for rework.
1285 * For example, each command could either have its own handler, so
1286 * the loop would look like:
1287 * while (cmds)
1288 * cmd->handle(x, y, z)
1289 * --jgrimm
1290 */
1291 while (NULL != (cmd = sctp_next_cmd(commands))) {
1292 switch (cmd->verb) {
1293 case SCTP_CMD_NOP:
1294 /* Do nothing. */
1295 break;
1296
1297 case SCTP_CMD_NEW_ASOC:
1298 /* Register a new association. */
1299 if (local_cork) {
1300 sctp_outq_uncork(&asoc->outqueue, gfp);
1301 local_cork = 0;
1302 }
1303
1304 /* Register with the endpoint. */
1305 asoc = cmd->obj.asoc;
1306 BUG_ON(asoc->peer.primary_path == NULL);
1307 sctp_endpoint_add_asoc(ep, asoc);
1308 break;
1309
1310 case SCTP_CMD_UPDATE_ASSOC:
1311 sctp_cmd_assoc_update(commands, asoc, cmd->obj.asoc);
1312 break;
1313
1314 case SCTP_CMD_PURGE_OUTQUEUE:
1315 sctp_outq_teardown(&asoc->outqueue);
1316 break;
1317
1318 case SCTP_CMD_DELETE_TCB:
1319 if (local_cork) {
1320 sctp_outq_uncork(&asoc->outqueue, gfp);
1321 local_cork = 0;
1322 }
1323 /* Delete the current association. */
1324 sctp_cmd_delete_tcb(commands, asoc);
1325 asoc = NULL;
1326 break;
1327
1328 case SCTP_CMD_NEW_STATE:
1329 /* Enter a new state. */
1330 sctp_cmd_new_state(commands, asoc, cmd->obj.state);
1331 break;
1332
1333 case SCTP_CMD_REPORT_TSN:
1334 /* Record the arrival of a TSN. */
1335 error = sctp_tsnmap_mark(&asoc->peer.tsn_map,
1336 cmd->obj.u32, NULL);
1337 break;
1338
1339 case SCTP_CMD_REPORT_FWDTSN:
1340 asoc->stream.si->report_ftsn(&asoc->ulpq, cmd->obj.u32);
1341 break;
1342
1343 case SCTP_CMD_PROCESS_FWDTSN:
1344 asoc->stream.si->handle_ftsn(&asoc->ulpq,
1345 cmd->obj.chunk);
1346 break;
1347
1348 case SCTP_CMD_GEN_SACK:
1349 /* Generate a Selective ACK.
1350 * The argument tells us whether to just count
1351 * the packet and MAYBE generate a SACK, or
1352 * force a SACK out.
1353 */
1354 force = cmd->obj.i32;
1355 error = sctp_gen_sack(asoc, force, commands);
1356 break;
1357
1358 case SCTP_CMD_PROCESS_SACK:
1359 /* Process an inbound SACK. */
1360 error = sctp_cmd_process_sack(commands, asoc,
1361 cmd->obj.chunk);
1362 break;
1363
1364 case SCTP_CMD_GEN_INIT_ACK:
1365 /* Generate an INIT ACK chunk. */
1366 new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC,
1367 0);
1368 if (!new_obj) {
1369 error = -ENOMEM;
1370 break;
1371 }
1372
1373 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1374 SCTP_CHUNK(new_obj));
1375 break;
1376
1377 case SCTP_CMD_PEER_INIT:
1378 /* Process a unified INIT from the peer.
1379 * Note: Only used during INIT-ACK processing. If
1380 * there is an error just return to the outter
1381 * layer which will bail.
1382 */
1383 error = sctp_cmd_process_init(commands, asoc, chunk,
1384 cmd->obj.init, gfp);
1385 break;
1386
1387 case SCTP_CMD_GEN_COOKIE_ECHO:
1388 /* Generate a COOKIE ECHO chunk. */
1389 new_obj = sctp_make_cookie_echo(asoc, chunk);
1390 if (!new_obj) {
1391 if (cmd->obj.chunk)
1392 sctp_chunk_free(cmd->obj.chunk);
1393 error = -ENOMEM;
1394 break;
1395 }
1396 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1397 SCTP_CHUNK(new_obj));
1398
1399 /* If there is an ERROR chunk to be sent along with
1400 * the COOKIE_ECHO, send it, too.
1401 */
1402 if (cmd->obj.chunk)
1403 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1404 SCTP_CHUNK(cmd->obj.chunk));
1405
1406 if (new_obj->transport) {
1407 new_obj->transport->init_sent_count++;
1408 asoc->init_last_sent_to = new_obj->transport;
1409 }
1410
1411 /* FIXME - Eventually come up with a cleaner way to
1412 * enabling COOKIE-ECHO + DATA bundling during
1413 * multihoming stale cookie scenarios, the following
1414 * command plays with asoc->peer.retran_path to
1415 * avoid the problem of sending the COOKIE-ECHO and
1416 * DATA in different paths, which could result
1417 * in the association being ABORTed if the DATA chunk
1418 * is processed first by the server. Checking the
1419 * init error counter simply causes this command
1420 * to be executed only during failed attempts of
1421 * association establishment.
1422 */
1423 if ((asoc->peer.retran_path !=
1424 asoc->peer.primary_path) &&
1425 (asoc->init_err_counter > 0)) {
1426 sctp_add_cmd_sf(commands,
1427 SCTP_CMD_FORCE_PRIM_RETRAN,
1428 SCTP_NULL());
1429 }
1430
1431 break;
1432
1433 case SCTP_CMD_GEN_SHUTDOWN:
1434 /* Generate SHUTDOWN when in SHUTDOWN_SENT state.
1435 * Reset error counts.
1436 */
1437 asoc->overall_error_count = 0;
1438
1439 /* Generate a SHUTDOWN chunk. */
1440 new_obj = sctp_make_shutdown(asoc, chunk);
1441 if (!new_obj) {
1442 error = -ENOMEM;
1443 break;
1444 }
1445 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1446 SCTP_CHUNK(new_obj));
1447 break;
1448
1449 case SCTP_CMD_CHUNK_ULP:
1450 /* Send a chunk to the sockets layer. */
1451 pr_debug("%s: sm_sideff: chunk_up:%p, ulpq:%p\n",
1452 __func__, cmd->obj.chunk, &asoc->ulpq);
1453
1454 asoc->stream.si->ulpevent_data(&asoc->ulpq,
1455 cmd->obj.chunk,
1456 GFP_ATOMIC);
1457 break;
1458
1459 case SCTP_CMD_EVENT_ULP:
1460 /* Send a notification to the sockets layer. */
1461 pr_debug("%s: sm_sideff: event_up:%p, ulpq:%p\n",
1462 __func__, cmd->obj.ulpevent, &asoc->ulpq);
1463
1464 asoc->stream.si->enqueue_event(&asoc->ulpq,
1465 cmd->obj.ulpevent);
1466 break;
1467
1468 case SCTP_CMD_REPLY:
1469 /* If an caller has not already corked, do cork. */
1470 if (!asoc->outqueue.cork) {
1471 sctp_outq_cork(&asoc->outqueue);
1472 local_cork = 1;
1473 }
1474 /* Send a chunk to our peer. */
1475 sctp_outq_tail(&asoc->outqueue, cmd->obj.chunk, gfp);
1476 break;
1477
1478 case SCTP_CMD_SEND_PKT:
1479 /* Send a full packet to our peer. */
1480 packet = cmd->obj.packet;
1481 sctp_packet_transmit(packet, gfp);
1482 sctp_ootb_pkt_free(packet);
1483 break;
1484
1485 case SCTP_CMD_T1_RETRAN:
1486 /* Mark a transport for retransmission. */
1487 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1488 SCTP_RTXR_T1_RTX);
1489 break;
1490
1491 case SCTP_CMD_RETRAN:
1492 /* Mark a transport for retransmission. */
1493 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1494 SCTP_RTXR_T3_RTX);
1495 break;
1496
1497 case SCTP_CMD_ECN_CE:
1498 /* Do delayed CE processing. */
1499 sctp_do_ecn_ce_work(asoc, cmd->obj.u32);
1500 break;
1501
1502 case SCTP_CMD_ECN_ECNE:
1503 /* Do delayed ECNE processing. */
1504 new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32,
1505 chunk);
1506 if (new_obj)
1507 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1508 SCTP_CHUNK(new_obj));
1509 break;
1510
1511 case SCTP_CMD_ECN_CWR:
1512 /* Do delayed CWR processing. */
1513 sctp_do_ecn_cwr_work(asoc, cmd->obj.u32);
1514 break;
1515
1516 case SCTP_CMD_SETUP_T2:
1517 sctp_cmd_setup_t2(commands, asoc, cmd->obj.chunk);
1518 break;
1519
1520 case SCTP_CMD_TIMER_START_ONCE:
1521 timer = &asoc->timers[cmd->obj.to];
1522
1523 if (timer_pending(timer))
1524 break;
1525 /* fall through */
1526
1527 case SCTP_CMD_TIMER_START:
1528 timer = &asoc->timers[cmd->obj.to];
1529 timeout = asoc->timeouts[cmd->obj.to];
1530 BUG_ON(!timeout);
1531
1532 /*
1533 * SCTP has a hard time with timer starts. Because we process
1534 * timer starts as side effects, it can be hard to tell if we
1535 * have already started a timer or not, which leads to BUG
1536 * halts when we call add_timer. So here, instead of just starting
1537 * a timer, if the timer is already started, and just mod
1538 * the timer with the shorter of the two expiration times
1539 */
1540 if (!timer_pending(timer))
1541 sctp_association_hold(asoc);
1542 timer_reduce(timer, jiffies + timeout);
1543 break;
1544
1545 case SCTP_CMD_TIMER_RESTART:
1546 timer = &asoc->timers[cmd->obj.to];
1547 timeout = asoc->timeouts[cmd->obj.to];
1548 if (!mod_timer(timer, jiffies + timeout))
1549 sctp_association_hold(asoc);
1550 break;
1551
1552 case SCTP_CMD_TIMER_STOP:
1553 timer = &asoc->timers[cmd->obj.to];
1554 if (del_timer(timer))
1555 sctp_association_put(asoc);
1556 break;
1557
1558 case SCTP_CMD_INIT_CHOOSE_TRANSPORT:
1559 chunk = cmd->obj.chunk;
1560 t = sctp_assoc_choose_alter_transport(asoc,
1561 asoc->init_last_sent_to);
1562 asoc->init_last_sent_to = t;
1563 chunk->transport = t;
1564 t->init_sent_count++;
1565 /* Set the new transport as primary */
1566 sctp_assoc_set_primary(asoc, t);
1567 break;
1568
1569 case SCTP_CMD_INIT_RESTART:
1570 /* Do the needed accounting and updates
1571 * associated with restarting an initialization
1572 * timer. Only multiply the timeout by two if
1573 * all transports have been tried at the current
1574 * timeout.
1575 */
1576 sctp_cmd_t1_timer_update(asoc,
1577 SCTP_EVENT_TIMEOUT_T1_INIT,
1578 "INIT");
1579
1580 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
1581 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
1582 break;
1583
1584 case SCTP_CMD_COOKIEECHO_RESTART:
1585 /* Do the needed accounting and updates
1586 * associated with restarting an initialization
1587 * timer. Only multiply the timeout by two if
1588 * all transports have been tried at the current
1589 * timeout.
1590 */
1591 sctp_cmd_t1_timer_update(asoc,
1592 SCTP_EVENT_TIMEOUT_T1_COOKIE,
1593 "COOKIE");
1594
1595 /* If we've sent any data bundled with
1596 * COOKIE-ECHO we need to resend.
1597 */
1598 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1599 transports) {
1600 sctp_retransmit_mark(&asoc->outqueue, t,
1601 SCTP_RTXR_T1_RTX);
1602 }
1603
1604 sctp_add_cmd_sf(commands,
1605 SCTP_CMD_TIMER_RESTART,
1606 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
1607 break;
1608
1609 case SCTP_CMD_INIT_FAILED:
1610 sctp_cmd_init_failed(commands, asoc, cmd->obj.u16);
1611 break;
1612
1613 case SCTP_CMD_ASSOC_FAILED:
1614 sctp_cmd_assoc_failed(commands, asoc, event_type,
1615 subtype, chunk, cmd->obj.u16);
1616 break;
1617
1618 case SCTP_CMD_INIT_COUNTER_INC:
1619 asoc->init_err_counter++;
1620 break;
1621
1622 case SCTP_CMD_INIT_COUNTER_RESET:
1623 asoc->init_err_counter = 0;
1624 asoc->init_cycle = 0;
1625 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1626 transports) {
1627 t->init_sent_count = 0;
1628 }
1629 break;
1630
1631 case SCTP_CMD_REPORT_DUP:
1632 sctp_tsnmap_mark_dup(&asoc->peer.tsn_map,
1633 cmd->obj.u32);
1634 break;
1635
1636 case SCTP_CMD_REPORT_BAD_TAG:
1637 pr_debug("%s: vtag mismatch!\n", __func__);
1638 break;
1639
1640 case SCTP_CMD_STRIKE:
1641 /* Mark one strike against a transport. */
1642 sctp_do_8_2_transport_strike(commands, asoc,
1643 cmd->obj.transport, 0);
1644 break;
1645
1646 case SCTP_CMD_TRANSPORT_IDLE:
1647 t = cmd->obj.transport;
1648 sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE);
1649 break;
1650
1651 case SCTP_CMD_TRANSPORT_HB_SENT:
1652 t = cmd->obj.transport;
1653 sctp_do_8_2_transport_strike(commands, asoc,
1654 t, 1);
1655 t->hb_sent = 1;
1656 break;
1657
1658 case SCTP_CMD_TRANSPORT_ON:
1659 t = cmd->obj.transport;
1660 sctp_cmd_transport_on(commands, asoc, t, chunk);
1661 break;
1662
1663 case SCTP_CMD_HB_TIMERS_START:
1664 sctp_cmd_hb_timers_start(commands, asoc);
1665 break;
1666
1667 case SCTP_CMD_HB_TIMER_UPDATE:
1668 t = cmd->obj.transport;
1669 sctp_transport_reset_hb_timer(t);
1670 break;
1671
1672 case SCTP_CMD_HB_TIMERS_STOP:
1673 sctp_cmd_hb_timers_stop(commands, asoc);
1674 break;
1675
1676 case SCTP_CMD_REPORT_ERROR:
1677 error = cmd->obj.error;
1678 break;
1679
1680 case SCTP_CMD_PROCESS_CTSN:
1681 /* Dummy up a SACK for processing. */
1682 sackh.cum_tsn_ack = cmd->obj.be32;
1683 sackh.a_rwnd = htonl(asoc->peer.rwnd +
1684 asoc->outqueue.outstanding_bytes);
1685 sackh.num_gap_ack_blocks = 0;
1686 sackh.num_dup_tsns = 0;
1687 chunk->subh.sack_hdr = &sackh;
1688 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK,
1689 SCTP_CHUNK(chunk));
1690 break;
1691
1692 case SCTP_CMD_DISCARD_PACKET:
1693 /* We need to discard the whole packet.
1694 * Uncork the queue since there might be
1695 * responses pending
1696 */
1697 chunk->pdiscard = 1;
1698 if (asoc) {
1699 sctp_outq_uncork(&asoc->outqueue, gfp);
1700 local_cork = 0;
1701 }
1702 break;
1703
1704 case SCTP_CMD_RTO_PENDING:
1705 t = cmd->obj.transport;
1706 t->rto_pending = 1;
1707 break;
1708
1709 case SCTP_CMD_PART_DELIVER:
1710 asoc->stream.si->start_pd(&asoc->ulpq, GFP_ATOMIC);
1711 break;
1712
1713 case SCTP_CMD_RENEGE:
1714 asoc->stream.si->renege_events(&asoc->ulpq,
1715 cmd->obj.chunk,
1716 GFP_ATOMIC);
1717 break;
1718
1719 case SCTP_CMD_SETUP_T4:
1720 sctp_cmd_setup_t4(commands, asoc, cmd->obj.chunk);
1721 break;
1722
1723 case SCTP_CMD_PROCESS_OPERR:
1724 sctp_cmd_process_operr(commands, asoc, chunk);
1725 break;
1726 case SCTP_CMD_CLEAR_INIT_TAG:
1727 asoc->peer.i.init_tag = 0;
1728 break;
1729 case SCTP_CMD_DEL_NON_PRIMARY:
1730 sctp_cmd_del_non_primary(asoc);
1731 break;
1732 case SCTP_CMD_T3_RTX_TIMERS_STOP:
1733 sctp_cmd_t3_rtx_timers_stop(commands, asoc);
1734 break;
1735 case SCTP_CMD_FORCE_PRIM_RETRAN:
1736 t = asoc->peer.retran_path;
1737 asoc->peer.retran_path = asoc->peer.primary_path;
1738 sctp_outq_uncork(&asoc->outqueue, gfp);
1739 local_cork = 0;
1740 asoc->peer.retran_path = t;
1741 break;
1742 case SCTP_CMD_SET_SK_ERR:
1743 sctp_cmd_set_sk_err(asoc, cmd->obj.error);
1744 break;
1745 case SCTP_CMD_ASSOC_CHANGE:
1746 sctp_cmd_assoc_change(commands, asoc,
1747 cmd->obj.u8);
1748 break;
1749 case SCTP_CMD_ADAPTATION_IND:
1750 sctp_cmd_adaptation_ind(commands, asoc);
1751 break;
1752 case SCTP_CMD_PEER_NO_AUTH:
1753 sctp_cmd_peer_no_auth(commands, asoc);
1754 break;
1755
1756 case SCTP_CMD_ASSOC_SHKEY:
1757 error = sctp_auth_asoc_init_active_key(asoc,
1758 GFP_ATOMIC);
1759 break;
1760 case SCTP_CMD_UPDATE_INITTAG:
1761 asoc->peer.i.init_tag = cmd->obj.u32;
1762 break;
1763 case SCTP_CMD_SEND_MSG:
1764 if (!asoc->outqueue.cork) {
1765 sctp_outq_cork(&asoc->outqueue);
1766 local_cork = 1;
1767 }
1768 sctp_cmd_send_msg(asoc, cmd->obj.msg, gfp);
1769 break;
1770 case SCTP_CMD_PURGE_ASCONF_QUEUE:
1771 sctp_asconf_queue_teardown(asoc);
1772 break;
1773
1774 case SCTP_CMD_SET_ASOC:
1775 if (asoc && local_cork) {
1776 sctp_outq_uncork(&asoc->outqueue, gfp);
1777 local_cork = 0;
1778 }
1779 asoc = cmd->obj.asoc;
1780 break;
1781
1782 default:
1783 pr_warn("Impossible command: %u\n",
1784 cmd->verb);
1785 break;
1786 }
1787
1788 if (error) {
1789 cmd = sctp_next_cmd(commands);
1790 while (cmd) {
1791 if (cmd->verb == SCTP_CMD_REPLY)
1792 sctp_chunk_free(cmd->obj.chunk);
1793 cmd = sctp_next_cmd(commands);
1794 }
1795 break;
1796 }
1797 }
1798
1799 /* If this is in response to a received chunk, wait until
1800 * we are done with the packet to open the queue so that we don't
1801 * send multiple packets in response to a single request.
1802 */
1803 if (asoc && SCTP_EVENT_T_CHUNK == event_type && chunk) {
1804 if (chunk->end_of_packet || chunk->singleton)
1805 sctp_outq_uncork(&asoc->outqueue, gfp);
1806 } else if (local_cork)
1807 sctp_outq_uncork(&asoc->outqueue, gfp);
1808
1809 if (sp->data_ready_signalled)
1810 sp->data_ready_signalled = 0;
1811
1812 return error;
1813 }
1814