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Linux 3.8-rc7
[cris-mirror.git] / net / sctp / sm_sideeffect.c
blobc9577754a70825cd00da2a24854a441c93dac09a
1 /* SCTP kernel implementation
2 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 *
6 * This file is part of the SCTP kernel implementation
7 *
8 * These functions work with the state functions in sctp_sm_statefuns.c
9 * to implement that state operations. These functions implement the
10 * steps which require modifying existing data structures.
11 *
12 * This SCTP implementation is free software;
13 * you can redistribute it and/or modify it under the terms of
14 * the GNU General Public License as published by
15 * the Free Software Foundation; either version 2, or (at your option)
16 * any later version.
17 *
18 * This SCTP implementation is distributed in the hope that it
19 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
20 * ************************
21 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
22 * See the GNU General Public License for more details.
23 *
24 * You should have received a copy of the GNU General Public License
25 * along with GNU CC; see the file COPYING. If not, write to
26 * the Free Software Foundation, 59 Temple Place - Suite 330,
27 * Boston, MA 02111-1307, USA.
28 *
29 * Please send any bug reports or fixes you make to the
30 * email address(es):
31 * lksctp developers <lksctp-developers@lists.sourceforge.net>
32 *
33 * Or submit a bug report through the following website:
34 * http://www.sf.net/projects/lksctp
35 *
36 * Written or modified by:
37 * La Monte H.P. Yarroll <piggy@acm.org>
38 * Karl Knutson <karl@athena.chicago.il.us>
39 * Jon Grimm <jgrimm@austin.ibm.com>
40 * Hui Huang <hui.huang@nokia.com>
41 * Dajiang Zhang <dajiang.zhang@nokia.com>
42 * Daisy Chang <daisyc@us.ibm.com>
43 * Sridhar Samudrala <sri@us.ibm.com>
44 * Ardelle Fan <ardelle.fan@intel.com>
45 *
46 * Any bugs reported given to us we will try to fix... any fixes shared will
47 * be incorporated into the next SCTP release.
48 */
49
50 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
51
52 #include <linux/skbuff.h>
53 #include <linux/types.h>
54 #include <linux/socket.h>
55 #include <linux/ip.h>
56 #include <linux/gfp.h>
57 #include <net/sock.h>
58 #include <net/sctp/sctp.h>
59 #include <net/sctp/sm.h>
60
61 static int sctp_cmd_interpreter(sctp_event_t event_type,
62 sctp_subtype_t subtype,
63 sctp_state_t state,
64 struct sctp_endpoint *ep,
65 struct sctp_association *asoc,
66 void *event_arg,
67 sctp_disposition_t status,
68 sctp_cmd_seq_t *commands,
69 gfp_t gfp);
70 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
71 sctp_state_t state,
72 struct sctp_endpoint *ep,
73 struct sctp_association *asoc,
74 void *event_arg,
75 sctp_disposition_t status,
76 sctp_cmd_seq_t *commands,
77 gfp_t gfp);
78
79 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds,
80 struct sctp_transport *t);
81 /********************************************************************
82 * Helper functions
83 ********************************************************************/
84
85 /* A helper function for delayed processing of INET ECN CE bit. */
86 static void sctp_do_ecn_ce_work(struct sctp_association *asoc,
87 __u32 lowest_tsn)
88 {
89 /* Save the TSN away for comparison when we receive CWR */
90
91 asoc->last_ecne_tsn = lowest_tsn;
92 asoc->need_ecne = 1;
93 }
94
95 /* Helper function for delayed processing of SCTP ECNE chunk. */
96 /* RFC 2960 Appendix A
97 *
98 * RFC 2481 details a specific bit for a sender to send in
99 * the header of its next outbound TCP segment to indicate to
100 * its peer that it has reduced its congestion window. This
101 * is termed the CWR bit. For SCTP the same indication is made
102 * by including the CWR chunk. This chunk contains one data
103 * element, i.e. the TSN number that was sent in the ECNE chunk.
104 * This element represents the lowest TSN number in the datagram
105 * that was originally marked with the CE bit.
106 */
107 static struct sctp_chunk *sctp_do_ecn_ecne_work(struct sctp_association *asoc,
108 __u32 lowest_tsn,
109 struct sctp_chunk *chunk)
110 {
111 struct sctp_chunk *repl;
112
113 /* Our previously transmitted packet ran into some congestion
114 * so we should take action by reducing cwnd and ssthresh
115 * and then ACK our peer that we we've done so by
116 * sending a CWR.
117 */
118
119 /* First, try to determine if we want to actually lower
120 * our cwnd variables. Only lower them if the ECNE looks more
121 * recent than the last response.
122 */
123 if (TSN_lt(asoc->last_cwr_tsn, lowest_tsn)) {
124 struct sctp_transport *transport;
125
126 /* Find which transport's congestion variables
127 * need to be adjusted.
128 */
129 transport = sctp_assoc_lookup_tsn(asoc, lowest_tsn);
130
131 /* Update the congestion variables. */
132 if (transport)
133 sctp_transport_lower_cwnd(transport,
134 SCTP_LOWER_CWND_ECNE);
135 asoc->last_cwr_tsn = lowest_tsn;
136 }
137
138 /* Always try to quiet the other end. In case of lost CWR,
139 * resend last_cwr_tsn.
140 */
141 repl = sctp_make_cwr(asoc, asoc->last_cwr_tsn, chunk);
142
143 /* If we run out of memory, it will look like a lost CWR. We'll
144 * get back in sync eventually.
145 */
146 return repl;
147 }
148
149 /* Helper function to do delayed processing of ECN CWR chunk. */
150 static void sctp_do_ecn_cwr_work(struct sctp_association *asoc,
151 __u32 lowest_tsn)
152 {
153 /* Turn off ECNE getting auto-prepended to every outgoing
154 * packet
155 */
156 asoc->need_ecne = 0;
157 }
158
159 /* Generate SACK if necessary. We call this at the end of a packet. */
160 static int sctp_gen_sack(struct sctp_association *asoc, int force,
161 sctp_cmd_seq_t *commands)
162 {
163 __u32 ctsn, max_tsn_seen;
164 struct sctp_chunk *sack;
165 struct sctp_transport *trans = asoc->peer.last_data_from;
166 int error = 0;
167
168 if (force ||
169 (!trans && (asoc->param_flags & SPP_SACKDELAY_DISABLE)) ||
170 (trans && (trans->param_flags & SPP_SACKDELAY_DISABLE)))
171 asoc->peer.sack_needed = 1;
172
173 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
174 max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
175
176 /* From 12.2 Parameters necessary per association (i.e. the TCB):
177 *
178 * Ack State : This flag indicates if the next received packet
179 * : is to be responded to with a SACK. ...
180 * : When DATA chunks are out of order, SACK's
181 * : are not delayed (see Section 6).
182 *
183 * [This is actually not mentioned in Section 6, but we
184 * implement it here anyway. --piggy]
185 */
186 if (max_tsn_seen != ctsn)
187 asoc->peer.sack_needed = 1;
188
189 /* From 6.2 Acknowledgement on Reception of DATA Chunks:
190 *
191 * Section 4.2 of [RFC2581] SHOULD be followed. Specifically,
192 * an acknowledgement SHOULD be generated for at least every
193 * second packet (not every second DATA chunk) received, and
194 * SHOULD be generated within 200 ms of the arrival of any
195 * unacknowledged DATA chunk. ...
196 */
197 if (!asoc->peer.sack_needed) {
198 asoc->peer.sack_cnt++;
199
200 /* Set the SACK delay timeout based on the
201 * SACK delay for the last transport
202 * data was received from, or the default
203 * for the association.
204 */
205 if (trans) {
206 /* We will need a SACK for the next packet. */
207 if (asoc->peer.sack_cnt >= trans->sackfreq - 1)
208 asoc->peer.sack_needed = 1;
209
210 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
211 trans->sackdelay;
212 } else {
213 /* We will need a SACK for the next packet. */
214 if (asoc->peer.sack_cnt >= asoc->sackfreq - 1)
215 asoc->peer.sack_needed = 1;
216
217 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
218 asoc->sackdelay;
219 }
220
221 /* Restart the SACK timer. */
222 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
223 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
224 } else {
225 asoc->a_rwnd = asoc->rwnd;
226 sack = sctp_make_sack(asoc);
227 if (!sack)
228 goto nomem;
229
230 asoc->peer.sack_needed = 0;
231 asoc->peer.sack_cnt = 0;
232
233 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(sack));
234
235 /* Stop the SACK timer. */
236 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
237 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
238 }
239
240 return error;
241 nomem:
242 error = -ENOMEM;
243 return error;
244 }
245
246 /* When the T3-RTX timer expires, it calls this function to create the
247 * relevant state machine event.
248 */
249 void sctp_generate_t3_rtx_event(unsigned long peer)
250 {
251 int error;
252 struct sctp_transport *transport = (struct sctp_transport *) peer;
253 struct sctp_association *asoc = transport->asoc;
254 struct net *net = sock_net(asoc->base.sk);
255
256 /* Check whether a task is in the sock. */
257
258 sctp_bh_lock_sock(asoc->base.sk);
259 if (sock_owned_by_user(asoc->base.sk)) {
260 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
261
262 /* Try again later. */
263 if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20)))
264 sctp_transport_hold(transport);
265 goto out_unlock;
266 }
267
268 /* Is this transport really dead and just waiting around for
269 * the timer to let go of the reference?
270 */
271 if (transport->dead)
272 goto out_unlock;
273
274 /* Run through the state machine. */
275 error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
276 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX),
277 asoc->state,
278 asoc->ep, asoc,
279 transport, GFP_ATOMIC);
280
281 if (error)
282 asoc->base.sk->sk_err = -error;
283
284 out_unlock:
285 sctp_bh_unlock_sock(asoc->base.sk);
286 sctp_transport_put(transport);
287 }
288
289 /* This is a sa interface for producing timeout events. It works
290 * for timeouts which use the association as their parameter.
291 */
292 static void sctp_generate_timeout_event(struct sctp_association *asoc,
293 sctp_event_timeout_t timeout_type)
294 {
295 struct net *net = sock_net(asoc->base.sk);
296 int error = 0;
297
298 sctp_bh_lock_sock(asoc->base.sk);
299 if (sock_owned_by_user(asoc->base.sk)) {
300 SCTP_DEBUG_PRINTK("%s:Sock is busy: timer %d\n",
301 __func__,
302 timeout_type);
303
304 /* Try again later. */
305 if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20)))
306 sctp_association_hold(asoc);
307 goto out_unlock;
308 }
309
310 /* Is this association really dead and just waiting around for
311 * the timer to let go of the reference?
312 */
313 if (asoc->base.dead)
314 goto out_unlock;
315
316 /* Run through the state machine. */
317 error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
318 SCTP_ST_TIMEOUT(timeout_type),
319 asoc->state, asoc->ep, asoc,
320 (void *)timeout_type, GFP_ATOMIC);
321
322 if (error)
323 asoc->base.sk->sk_err = -error;
324
325 out_unlock:
326 sctp_bh_unlock_sock(asoc->base.sk);
327 sctp_association_put(asoc);
328 }
329
330 static void sctp_generate_t1_cookie_event(unsigned long data)
331 {
332 struct sctp_association *asoc = (struct sctp_association *) data;
333 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE);
334 }
335
336 static void sctp_generate_t1_init_event(unsigned long data)
337 {
338 struct sctp_association *asoc = (struct sctp_association *) data;
339 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT);
340 }
341
342 static void sctp_generate_t2_shutdown_event(unsigned long data)
343 {
344 struct sctp_association *asoc = (struct sctp_association *) data;
345 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN);
346 }
347
348 static void sctp_generate_t4_rto_event(unsigned long data)
349 {
350 struct sctp_association *asoc = (struct sctp_association *) data;
351 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO);
352 }
353
354 static void sctp_generate_t5_shutdown_guard_event(unsigned long data)
355 {
356 struct sctp_association *asoc = (struct sctp_association *)data;
357 sctp_generate_timeout_event(asoc,
358 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD);
359
360 } /* sctp_generate_t5_shutdown_guard_event() */
361
362 static void sctp_generate_autoclose_event(unsigned long data)
363 {
364 struct sctp_association *asoc = (struct sctp_association *) data;
365 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE);
366 }
367
368 /* Generate a heart beat event. If the sock is busy, reschedule. Make
369 * sure that the transport is still valid.
370 */
371 void sctp_generate_heartbeat_event(unsigned long data)
372 {
373 int error = 0;
374 struct sctp_transport *transport = (struct sctp_transport *) data;
375 struct sctp_association *asoc = transport->asoc;
376 struct net *net = sock_net(asoc->base.sk);
377
378 sctp_bh_lock_sock(asoc->base.sk);
379 if (sock_owned_by_user(asoc->base.sk)) {
380 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
381
382 /* Try again later. */
383 if (!mod_timer(&transport->hb_timer, jiffies + (HZ/20)))
384 sctp_transport_hold(transport);
385 goto out_unlock;
386 }
387
388 /* Is this structure just waiting around for us to actually
389 * get destroyed?
390 */
391 if (transport->dead)
392 goto out_unlock;
393
394 error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
395 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT),
396 asoc->state, asoc->ep, asoc,
397 transport, GFP_ATOMIC);
398
399 if (error)
400 asoc->base.sk->sk_err = -error;
401
402 out_unlock:
403 sctp_bh_unlock_sock(asoc->base.sk);
404 sctp_transport_put(transport);
405 }
406
407 /* Handle the timeout of the ICMP protocol unreachable timer. Trigger
408 * the correct state machine transition that will close the association.
409 */
410 void sctp_generate_proto_unreach_event(unsigned long data)
411 {
412 struct sctp_transport *transport = (struct sctp_transport *) data;
413 struct sctp_association *asoc = transport->asoc;
414 struct net *net = sock_net(asoc->base.sk);
415
416 sctp_bh_lock_sock(asoc->base.sk);
417 if (sock_owned_by_user(asoc->base.sk)) {
418 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
419
420 /* Try again later. */
421 if (!mod_timer(&transport->proto_unreach_timer,
422 jiffies + (HZ/20)))
423 sctp_association_hold(asoc);
424 goto out_unlock;
425 }
426
427 /* Is this structure just waiting around for us to actually
428 * get destroyed?
429 */
430 if (asoc->base.dead)
431 goto out_unlock;
432
433 sctp_do_sm(net, SCTP_EVENT_T_OTHER,
434 SCTP_ST_OTHER(SCTP_EVENT_ICMP_PROTO_UNREACH),
435 asoc->state, asoc->ep, asoc, transport, GFP_ATOMIC);
436
437 out_unlock:
438 sctp_bh_unlock_sock(asoc->base.sk);
439 sctp_association_put(asoc);
440 }
441
442
443 /* Inject a SACK Timeout event into the state machine. */
444 static void sctp_generate_sack_event(unsigned long data)
445 {
446 struct sctp_association *asoc = (struct sctp_association *) data;
447 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK);
448 }
449
450 sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = {
451 NULL,
452 sctp_generate_t1_cookie_event,
453 sctp_generate_t1_init_event,
454 sctp_generate_t2_shutdown_event,
455 NULL,
456 sctp_generate_t4_rto_event,
457 sctp_generate_t5_shutdown_guard_event,
458 NULL,
459 sctp_generate_sack_event,
460 sctp_generate_autoclose_event,
461 };
462
463
464 /* RFC 2960 8.2 Path Failure Detection
465 *
466 * When its peer endpoint is multi-homed, an endpoint should keep a
467 * error counter for each of the destination transport addresses of the
468 * peer endpoint.
469 *
470 * Each time the T3-rtx timer expires on any address, or when a
471 * HEARTBEAT sent to an idle address is not acknowledged within a RTO,
472 * the error counter of that destination address will be incremented.
473 * When the value in the error counter exceeds the protocol parameter
474 * 'Path.Max.Retrans' of that destination address, the endpoint should
475 * mark the destination transport address as inactive, and a
476 * notification SHOULD be sent to the upper layer.
477 *
478 */
479 static void sctp_do_8_2_transport_strike(sctp_cmd_seq_t *commands,
480 struct sctp_association *asoc,
481 struct sctp_transport *transport,
482 int is_hb)
483 {
484 /* The check for association's overall error counter exceeding the
485 * threshold is done in the state function.
486 */
487 /* We are here due to a timer expiration. If the timer was
488 * not a HEARTBEAT, then normal error tracking is done.
489 * If the timer was a heartbeat, we only increment error counts
490 * when we already have an outstanding HEARTBEAT that has not
491 * been acknowledged.
492 * Additionally, some tranport states inhibit error increments.
493 */
494 if (!is_hb) {
495 asoc->overall_error_count++;
496 if (transport->state != SCTP_INACTIVE)
497 transport->error_count++;
498 } else if (transport->hb_sent) {
499 if (transport->state != SCTP_UNCONFIRMED)
500 asoc->overall_error_count++;
501 if (transport->state != SCTP_INACTIVE)
502 transport->error_count++;
503 }
504
505 /* If the transport error count is greater than the pf_retrans
506 * threshold, and less than pathmaxrtx, then mark this transport
507 * as Partially Failed, ee SCTP Quick Failover Draft, secon 5.1,
508 * point 1
509 */
510 if ((transport->state != SCTP_PF) &&
511 (asoc->pf_retrans < transport->pathmaxrxt) &&
512 (transport->error_count > asoc->pf_retrans)) {
513
514 sctp_assoc_control_transport(asoc, transport,
515 SCTP_TRANSPORT_PF,
516 0);
517
518 /* Update the hb timer to resend a heartbeat every rto */
519 sctp_cmd_hb_timer_update(commands, transport);
520 }
521
522 if (transport->state != SCTP_INACTIVE &&
523 (transport->error_count > transport->pathmaxrxt)) {
524 SCTP_DEBUG_PRINTK_IPADDR("transport_strike:association %p",
525 " transport IP: port:%d failed.\n",
526 asoc,
527 (&transport->ipaddr),
528 ntohs(transport->ipaddr.v4.sin_port));
529 sctp_assoc_control_transport(asoc, transport,
530 SCTP_TRANSPORT_DOWN,
531 SCTP_FAILED_THRESHOLD);
532 }
533
534 /* E2) For the destination address for which the timer
535 * expires, set RTO <- RTO * 2 ("back off the timer"). The
536 * maximum value discussed in rule C7 above (RTO.max) may be
537 * used to provide an upper bound to this doubling operation.
538 *
539 * Special Case: the first HB doesn't trigger exponential backoff.
540 * The first unacknowledged HB triggers it. We do this with a flag
541 * that indicates that we have an outstanding HB.
542 */
543 if (!is_hb || transport->hb_sent) {
544 transport->rto = min((transport->rto * 2), transport->asoc->rto_max);
545 sctp_max_rto(asoc, transport);
546 }
547 }
548
549 /* Worker routine to handle INIT command failure. */
550 static void sctp_cmd_init_failed(sctp_cmd_seq_t *commands,
551 struct sctp_association *asoc,
552 unsigned int error)
553 {
554 struct sctp_ulpevent *event;
555
556 event = sctp_ulpevent_make_assoc_change(asoc,0, SCTP_CANT_STR_ASSOC,
557 (__u16)error, 0, 0, NULL,
558 GFP_ATOMIC);
559
560 if (event)
561 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
562 SCTP_ULPEVENT(event));
563
564 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
565 SCTP_STATE(SCTP_STATE_CLOSED));
566
567 /* SEND_FAILED sent later when cleaning up the association. */
568 asoc->outqueue.error = error;
569 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
570 }
571
572 /* Worker routine to handle SCTP_CMD_ASSOC_FAILED. */
573 static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands,
574 struct sctp_association *asoc,
575 sctp_event_t event_type,
576 sctp_subtype_t subtype,
577 struct sctp_chunk *chunk,
578 unsigned int error)
579 {
580 struct sctp_ulpevent *event;
581 struct sctp_chunk *abort;
582 /* Cancel any partial delivery in progress. */
583 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
584
585 if (event_type == SCTP_EVENT_T_CHUNK && subtype.chunk == SCTP_CID_ABORT)
586 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
587 (__u16)error, 0, 0, chunk,
588 GFP_ATOMIC);
589 else
590 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
591 (__u16)error, 0, 0, NULL,
592 GFP_ATOMIC);
593 if (event)
594 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
595 SCTP_ULPEVENT(event));
596
597 if (asoc->overall_error_count >= asoc->max_retrans) {
598 abort = sctp_make_violation_max_retrans(asoc, chunk);
599 if (abort)
600 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
601 SCTP_CHUNK(abort));
602 }
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 /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT
613 * inside the cookie. In reality, this is only used for INIT-ACK processing
614 * since all other cases use "temporary" associations and can do all
615 * their work in statefuns directly.
616 */
617 static int sctp_cmd_process_init(sctp_cmd_seq_t *commands,
618 struct sctp_association *asoc,
619 struct sctp_chunk *chunk,
620 sctp_init_chunk_t *peer_init,
621 gfp_t gfp)
622 {
623 int error;
624
625 /* We only process the init as a sideeffect in a single
626 * case. This is when we process the INIT-ACK. If we
627 * fail during INIT processing (due to malloc problems),
628 * just return the error and stop processing the stack.
629 */
630 if (!sctp_process_init(asoc, chunk, sctp_source(chunk), peer_init, gfp))
631 error = -ENOMEM;
632 else
633 error = 0;
634
635 return error;
636 }
637
638 /* Helper function to break out starting up of heartbeat timers. */
639 static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds,
640 struct sctp_association *asoc)
641 {
642 struct sctp_transport *t;
643
644 /* Start a heartbeat timer for each transport on the association.
645 * hold a reference on the transport to make sure none of
646 * the needed data structures go away.
647 */
648 list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) {
649
650 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
651 sctp_transport_hold(t);
652 }
653 }
654
655 static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds,
656 struct sctp_association *asoc)
657 {
658 struct sctp_transport *t;
659
660 /* Stop all heartbeat timers. */
661
662 list_for_each_entry(t, &asoc->peer.transport_addr_list,
663 transports) {
664 if (del_timer(&t->hb_timer))
665 sctp_transport_put(t);
666 }
667 }
668
669 /* Helper function to stop any pending T3-RTX timers */
670 static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds,
671 struct sctp_association *asoc)
672 {
673 struct sctp_transport *t;
674
675 list_for_each_entry(t, &asoc->peer.transport_addr_list,
676 transports) {
677 if (timer_pending(&t->T3_rtx_timer) &&
678 del_timer(&t->T3_rtx_timer)) {
679 sctp_transport_put(t);
680 }
681 }
682 }
683
684
685 /* Helper function to update the heartbeat timer. */
686 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds,
687 struct sctp_transport *t)
688 {
689 /* Update the heartbeat timer. */
690 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
691 sctp_transport_hold(t);
692 }
693
694 /* Helper function to handle the reception of an HEARTBEAT ACK. */
695 static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds,
696 struct sctp_association *asoc,
697 struct sctp_transport *t,
698 struct sctp_chunk *chunk)
699 {
700 sctp_sender_hb_info_t *hbinfo;
701 int was_unconfirmed = 0;
702
703 /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the
704 * HEARTBEAT should clear the error counter of the destination
705 * transport address to which the HEARTBEAT was sent.
706 */
707 t->error_count = 0;
708
709 /*
710 * Although RFC4960 specifies that the overall error count must
711 * be cleared when a HEARTBEAT ACK is received, we make an
712 * exception while in SHUTDOWN PENDING. If the peer keeps its
713 * window shut forever, we may never be able to transmit our
714 * outstanding data and rely on the retransmission limit be reached
715 * to shutdown the association.
716 */
717 if (t->asoc->state != SCTP_STATE_SHUTDOWN_PENDING)
718 t->asoc->overall_error_count = 0;
719
720 /* Clear the hb_sent flag to signal that we had a good
721 * acknowledgement.
722 */
723 t->hb_sent = 0;
724
725 /* Mark the destination transport address as active if it is not so
726 * marked.
727 */
728 if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED)) {
729 was_unconfirmed = 1;
730 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
731 SCTP_HEARTBEAT_SUCCESS);
732 }
733
734 if (t->state == SCTP_PF)
735 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
736 SCTP_HEARTBEAT_SUCCESS);
737
738 /* The receiver of the HEARTBEAT ACK should also perform an
739 * RTT measurement for that destination transport address
740 * using the time value carried in the HEARTBEAT ACK chunk.
741 * If the transport's rto_pending variable has been cleared,
742 * it was most likely due to a retransmit. However, we want
743 * to re-enable it to properly update the rto.
744 */
745 if (t->rto_pending == 0)
746 t->rto_pending = 1;
747
748 hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data;
749 sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at));
750
751 /* Update the heartbeat timer. */
752 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
753 sctp_transport_hold(t);
754
755 if (was_unconfirmed && asoc->peer.transport_count == 1)
756 sctp_transport_immediate_rtx(t);
757 }
758
759
760 /* Helper function to process the process SACK command. */
761 static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds,
762 struct sctp_association *asoc,
763 struct sctp_chunk *chunk)
764 {
765 int err = 0;
766
767 if (sctp_outq_sack(&asoc->outqueue, chunk)) {
768 struct net *net = sock_net(asoc->base.sk);
769
770 /* There are no more TSNs awaiting SACK. */
771 err = sctp_do_sm(net, SCTP_EVENT_T_OTHER,
772 SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN),
773 asoc->state, asoc->ep, asoc, NULL,
774 GFP_ATOMIC);
775 }
776
777 return err;
778 }
779
780 /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set
781 * the transport for a shutdown chunk.
782 */
783 static void sctp_cmd_setup_t2(sctp_cmd_seq_t *cmds,
784 struct sctp_association *asoc,
785 struct sctp_chunk *chunk)
786 {
787 struct sctp_transport *t;
788
789 if (chunk->transport)
790 t = chunk->transport;
791 else {
792 t = sctp_assoc_choose_alter_transport(asoc,
793 asoc->shutdown_last_sent_to);
794 chunk->transport = t;
795 }
796 asoc->shutdown_last_sent_to = t;
797 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto;
798 }
799
800 /* Helper function to change the state of an association. */
801 static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds,
802 struct sctp_association *asoc,
803 sctp_state_t state)
804 {
805 struct sock *sk = asoc->base.sk;
806
807 asoc->state = state;
808
809 SCTP_DEBUG_PRINTK("sctp_cmd_new_state: asoc %p[%s]\n",
810 asoc, sctp_state_tbl[state]);
811
812 if (sctp_style(sk, TCP)) {
813 /* Change the sk->sk_state of a TCP-style socket that has
814 * successfully completed a connect() call.
815 */
816 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED))
817 sk->sk_state = SCTP_SS_ESTABLISHED;
818
819 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */
820 if (sctp_state(asoc, SHUTDOWN_RECEIVED) &&
821 sctp_sstate(sk, ESTABLISHED))
822 sk->sk_shutdown |= RCV_SHUTDOWN;
823 }
824
825 if (sctp_state(asoc, COOKIE_WAIT)) {
826 /* Reset init timeouts since they may have been
827 * increased due to timer expirations.
828 */
829 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
830 asoc->rto_initial;
831 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
832 asoc->rto_initial;
833 }
834
835 if (sctp_state(asoc, ESTABLISHED) ||
836 sctp_state(asoc, CLOSED) ||
837 sctp_state(asoc, SHUTDOWN_RECEIVED)) {
838 /* Wake up any processes waiting in the asoc's wait queue in
839 * sctp_wait_for_connect() or sctp_wait_for_sndbuf().
840 */
841 if (waitqueue_active(&asoc->wait))
842 wake_up_interruptible(&asoc->wait);
843
844 /* Wake up any processes waiting in the sk's sleep queue of
845 * a TCP-style or UDP-style peeled-off socket in
846 * sctp_wait_for_accept() or sctp_wait_for_packet().
847 * For a UDP-style socket, the waiters are woken up by the
848 * notifications.
849 */
850 if (!sctp_style(sk, UDP))
851 sk->sk_state_change(sk);
852 }
853 }
854
855 /* Helper function to delete an association. */
856 static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds,
857 struct sctp_association *asoc)
858 {
859 struct sock *sk = asoc->base.sk;
860
861 /* If it is a non-temporary association belonging to a TCP-style
862 * listening socket that is not closed, do not free it so that accept()
863 * can pick it up later.
864 */
865 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) &&
866 (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK))
867 return;
868
869 sctp_unhash_established(asoc);
870 sctp_association_free(asoc);
871 }
872
873 /*
874 * ADDIP Section 4.1 ASCONF Chunk Procedures
875 * A4) Start a T-4 RTO timer, using the RTO value of the selected
876 * destination address (we use active path instead of primary path just
877 * because primary path may be inactive.
878 */
879 static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds,
880 struct sctp_association *asoc,
881 struct sctp_chunk *chunk)
882 {
883 struct sctp_transport *t;
884
885 t = sctp_assoc_choose_alter_transport(asoc, chunk->transport);
886 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto;
887 chunk->transport = t;
888 }
889
890 /* Process an incoming Operation Error Chunk. */
891 static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds,
892 struct sctp_association *asoc,
893 struct sctp_chunk *chunk)
894 {
895 struct sctp_errhdr *err_hdr;
896 struct sctp_ulpevent *ev;
897
898 while (chunk->chunk_end > chunk->skb->data) {
899 err_hdr = (struct sctp_errhdr *)(chunk->skb->data);
900
901 ev = sctp_ulpevent_make_remote_error(asoc, chunk, 0,
902 GFP_ATOMIC);
903 if (!ev)
904 return;
905
906 sctp_ulpq_tail_event(&asoc->ulpq, ev);
907
908 switch (err_hdr->cause) {
909 case SCTP_ERROR_UNKNOWN_CHUNK:
910 {
911 sctp_chunkhdr_t *unk_chunk_hdr;
912
913 unk_chunk_hdr = (sctp_chunkhdr_t *)err_hdr->variable;
914 switch (unk_chunk_hdr->type) {
915 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with
916 * an ERROR chunk reporting that it did not recognized
917 * the ASCONF chunk type, the sender of the ASCONF MUST
918 * NOT send any further ASCONF chunks and MUST stop its
919 * T-4 timer.
920 */
921 case SCTP_CID_ASCONF:
922 if (asoc->peer.asconf_capable == 0)
923 break;
924
925 asoc->peer.asconf_capable = 0;
926 sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP,
927 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
928 break;
929 default:
930 break;
931 }
932 break;
933 }
934 default:
935 break;
936 }
937 }
938 }
939
940 /* Process variable FWDTSN chunk information. */
941 static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq,
942 struct sctp_chunk *chunk)
943 {
944 struct sctp_fwdtsn_skip *skip;
945 /* Walk through all the skipped SSNs */
946 sctp_walk_fwdtsn(skip, chunk) {
947 sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn));
948 }
949 }
950
951 /* Helper function to remove the association non-primary peer
952 * transports.
953 */
954 static void sctp_cmd_del_non_primary(struct sctp_association *asoc)
955 {
956 struct sctp_transport *t;
957 struct list_head *pos;
958 struct list_head *temp;
959
960 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
961 t = list_entry(pos, struct sctp_transport, transports);
962 if (!sctp_cmp_addr_exact(&t->ipaddr,
963 &asoc->peer.primary_addr)) {
964 sctp_assoc_del_peer(asoc, &t->ipaddr);
965 }
966 }
967 }
968
969 /* Helper function to set sk_err on a 1-1 style socket. */
970 static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error)
971 {
972 struct sock *sk = asoc->base.sk;
973
974 if (!sctp_style(sk, UDP))
975 sk->sk_err = error;
976 }
977
978 /* Helper function to generate an association change event */
979 static void sctp_cmd_assoc_change(sctp_cmd_seq_t *commands,
980 struct sctp_association *asoc,
981 u8 state)
982 {
983 struct sctp_ulpevent *ev;
984
985 ev = sctp_ulpevent_make_assoc_change(asoc, 0, state, 0,
986 asoc->c.sinit_num_ostreams,
987 asoc->c.sinit_max_instreams,
988 NULL, GFP_ATOMIC);
989 if (ev)
990 sctp_ulpq_tail_event(&asoc->ulpq, ev);
991 }
992
993 /* Helper function to generate an adaptation indication event */
994 static void sctp_cmd_adaptation_ind(sctp_cmd_seq_t *commands,
995 struct sctp_association *asoc)
996 {
997 struct sctp_ulpevent *ev;
998
999 ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC);
1000
1001 if (ev)
1002 sctp_ulpq_tail_event(&asoc->ulpq, ev);
1003 }
1004
1005
1006 static void sctp_cmd_t1_timer_update(struct sctp_association *asoc,
1007 sctp_event_timeout_t timer,
1008 char *name)
1009 {
1010 struct sctp_transport *t;
1011
1012 t = asoc->init_last_sent_to;
1013 asoc->init_err_counter++;
1014
1015 if (t->init_sent_count > (asoc->init_cycle + 1)) {
1016 asoc->timeouts[timer] *= 2;
1017 if (asoc->timeouts[timer] > asoc->max_init_timeo) {
1018 asoc->timeouts[timer] = asoc->max_init_timeo;
1019 }
1020 asoc->init_cycle++;
1021 SCTP_DEBUG_PRINTK(
1022 "T1 %s Timeout adjustment"
1023 " init_err_counter: %d"
1024 " cycle: %d"
1025 " timeout: %ld\n",
1026 name,
1027 asoc->init_err_counter,
1028 asoc->init_cycle,
1029 asoc->timeouts[timer]);
1030 }
1031
1032 }
1033
1034 /* Send the whole message, chunk by chunk, to the outqueue.
1035 * This way the whole message is queued up and bundling if
1036 * encouraged for small fragments.
1037 */
1038 static int sctp_cmd_send_msg(struct sctp_association *asoc,
1039 struct sctp_datamsg *msg)
1040 {
1041 struct sctp_chunk *chunk;
1042 int error = 0;
1043
1044 list_for_each_entry(chunk, &msg->chunks, frag_list) {
1045 error = sctp_outq_tail(&asoc->outqueue, chunk);
1046 if (error)
1047 break;
1048 }
1049
1050 return error;
1051 }
1052
1053
1054 /* Sent the next ASCONF packet currently stored in the association.
1055 * This happens after the ASCONF_ACK was succeffully processed.
1056 */
1057 static void sctp_cmd_send_asconf(struct sctp_association *asoc)
1058 {
1059 struct net *net = sock_net(asoc->base.sk);
1060
1061 /* Send the next asconf chunk from the addip chunk
1062 * queue.
1063 */
1064 if (!list_empty(&asoc->addip_chunk_list)) {
1065 struct list_head *entry = asoc->addip_chunk_list.next;
1066 struct sctp_chunk *asconf = list_entry(entry,
1067 struct sctp_chunk, list);
1068 list_del_init(entry);
1069
1070 /* Hold the chunk until an ASCONF_ACK is received. */
1071 sctp_chunk_hold(asconf);
1072 if (sctp_primitive_ASCONF(net, asoc, asconf))
1073 sctp_chunk_free(asconf);
1074 else
1075 asoc->addip_last_asconf = asconf;
1076 }
1077 }
1078
1079
1080 /* These three macros allow us to pull the debugging code out of the
1081 * main flow of sctp_do_sm() to keep attention focused on the real
1082 * functionality there.
1083 */
1084 #define DEBUG_PRE \
1085 SCTP_DEBUG_PRINTK("sctp_do_sm prefn: " \
1086 "ep %p, %s, %s, asoc %p[%s], %s\n", \
1087 ep, sctp_evttype_tbl[event_type], \
1088 (*debug_fn)(subtype), asoc, \
1089 sctp_state_tbl[state], state_fn->name)
1090
1091 #define DEBUG_POST \
1092 SCTP_DEBUG_PRINTK("sctp_do_sm postfn: " \
1093 "asoc %p, status: %s\n", \
1094 asoc, sctp_status_tbl[status])
1095
1096 #define DEBUG_POST_SFX \
1097 SCTP_DEBUG_PRINTK("sctp_do_sm post sfx: error %d, asoc %p[%s]\n", \
1098 error, asoc, \
1099 sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \
1100 sctp_assoc2id(asoc)))?asoc->state:SCTP_STATE_CLOSED])
1101
1102 /*
1103 * This is the master state machine processing function.
1104 *
1105 * If you want to understand all of lksctp, this is a
1106 * good place to start.
1107 */
1108 int sctp_do_sm(struct net *net, sctp_event_t event_type, sctp_subtype_t subtype,
1109 sctp_state_t state,
1110 struct sctp_endpoint *ep,
1111 struct sctp_association *asoc,
1112 void *event_arg,
1113 gfp_t gfp)
1114 {
1115 sctp_cmd_seq_t commands;
1116 const sctp_sm_table_entry_t *state_fn;
1117 sctp_disposition_t status;
1118 int error = 0;
1119 typedef const char *(printfn_t)(sctp_subtype_t);
1120
1121 static printfn_t *table[] = {
1122 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname,
1123 };
1124 printfn_t *debug_fn __attribute__ ((unused)) = table[event_type];
1125
1126 /* Look up the state function, run it, and then process the
1127 * side effects. These three steps are the heart of lksctp.
1128 */
1129 state_fn = sctp_sm_lookup_event(net, event_type, state, subtype);
1130
1131 sctp_init_cmd_seq(&commands);
1132
1133 DEBUG_PRE;
1134 status = (*state_fn->fn)(net, ep, asoc, subtype, event_arg, &commands);
1135 DEBUG_POST;
1136
1137 error = sctp_side_effects(event_type, subtype, state,
1138 ep, asoc, event_arg, status,
1139 &commands, gfp);
1140 DEBUG_POST_SFX;
1141
1142 return error;
1143 }
1144
1145 #undef DEBUG_PRE
1146 #undef DEBUG_POST
1147
1148 /*****************************************************************
1149 * This the master state function side effect processing function.
1150 *****************************************************************/
1151 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
1152 sctp_state_t state,
1153 struct sctp_endpoint *ep,
1154 struct sctp_association *asoc,
1155 void *event_arg,
1156 sctp_disposition_t status,
1157 sctp_cmd_seq_t *commands,
1158 gfp_t gfp)
1159 {
1160 int error;
1161
1162 /* FIXME - Most of the dispositions left today would be categorized
1163 * as "exceptional" dispositions. For those dispositions, it
1164 * may not be proper to run through any of the commands at all.
1165 * For example, the command interpreter might be run only with
1166 * disposition SCTP_DISPOSITION_CONSUME.
1167 */
1168 if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state,
1169 ep, asoc,
1170 event_arg, status,
1171 commands, gfp)))
1172 goto bail;
1173
1174 switch (status) {
1175 case SCTP_DISPOSITION_DISCARD:
1176 SCTP_DEBUG_PRINTK("Ignored sctp protocol event - state %d, "
1177 "event_type %d, event_id %d\n",
1178 state, event_type, subtype.chunk);
1179 break;
1180
1181 case SCTP_DISPOSITION_NOMEM:
1182 /* We ran out of memory, so we need to discard this
1183 * packet.
1184 */
1185 /* BUG--we should now recover some memory, probably by
1186 * reneging...
1187 */
1188 error = -ENOMEM;
1189 break;
1190
1191 case SCTP_DISPOSITION_DELETE_TCB:
1192 /* This should now be a command. */
1193 break;
1194
1195 case SCTP_DISPOSITION_CONSUME:
1196 case SCTP_DISPOSITION_ABORT:
1197 /*
1198 * We should no longer have much work to do here as the
1199 * real work has been done as explicit commands above.
1200 */
1201 break;
1202
1203 case SCTP_DISPOSITION_VIOLATION:
1204 net_err_ratelimited("protocol violation state %d chunkid %d\n",
1205 state, subtype.chunk);
1206 break;
1207
1208 case SCTP_DISPOSITION_NOT_IMPL:
1209 pr_warn("unimplemented feature in state %d, event_type %d, event_id %d\n",
1210 state, event_type, subtype.chunk);
1211 break;
1212
1213 case SCTP_DISPOSITION_BUG:
1214 pr_err("bug in state %d, event_type %d, event_id %d\n",
1215 state, event_type, subtype.chunk);
1216 BUG();
1217 break;
1218
1219 default:
1220 pr_err("impossible disposition %d in state %d, event_type %d, event_id %d\n",
1221 status, state, event_type, subtype.chunk);
1222 BUG();
1223 break;
1224 }
1225
1226 bail:
1227 return error;
1228 }
1229
1230 /********************************************************************
1231 * 2nd Level Abstractions
1232 ********************************************************************/
1233
1234 /* This is the side-effect interpreter. */
1235 static int sctp_cmd_interpreter(sctp_event_t event_type,
1236 sctp_subtype_t subtype,
1237 sctp_state_t state,
1238 struct sctp_endpoint *ep,
1239 struct sctp_association *asoc,
1240 void *event_arg,
1241 sctp_disposition_t status,
1242 sctp_cmd_seq_t *commands,
1243 gfp_t gfp)
1244 {
1245 int error = 0;
1246 int force;
1247 sctp_cmd_t *cmd;
1248 struct sctp_chunk *new_obj;
1249 struct sctp_chunk *chunk = NULL;
1250 struct sctp_packet *packet;
1251 struct timer_list *timer;
1252 unsigned long timeout;
1253 struct sctp_transport *t;
1254 struct sctp_sackhdr sackh;
1255 int local_cork = 0;
1256
1257 if (SCTP_EVENT_T_TIMEOUT != event_type)
1258 chunk = event_arg;
1259
1260 /* Note: This whole file is a huge candidate for rework.
1261 * For example, each command could either have its own handler, so
1262 * the loop would look like:
1263 * while (cmds)
1264 * cmd->handle(x, y, z)
1265 * --jgrimm
1266 */
1267 while (NULL != (cmd = sctp_next_cmd(commands))) {
1268 switch (cmd->verb) {
1269 case SCTP_CMD_NOP:
1270 /* Do nothing. */
1271 break;
1272
1273 case SCTP_CMD_NEW_ASOC:
1274 /* Register a new association. */
1275 if (local_cork) {
1276 sctp_outq_uncork(&asoc->outqueue);
1277 local_cork = 0;
1278 }
1279 asoc = cmd->obj.asoc;
1280 /* Register with the endpoint. */
1281 sctp_endpoint_add_asoc(ep, asoc);
1282 sctp_hash_established(asoc);
1283 break;
1284
1285 case SCTP_CMD_UPDATE_ASSOC:
1286 sctp_assoc_update(asoc, cmd->obj.asoc);
1287 break;
1288
1289 case SCTP_CMD_PURGE_OUTQUEUE:
1290 sctp_outq_teardown(&asoc->outqueue);
1291 break;
1292
1293 case SCTP_CMD_DELETE_TCB:
1294 if (local_cork) {
1295 sctp_outq_uncork(&asoc->outqueue);
1296 local_cork = 0;
1297 }
1298 /* Delete the current association. */
1299 sctp_cmd_delete_tcb(commands, asoc);
1300 asoc = NULL;
1301 break;
1302
1303 case SCTP_CMD_NEW_STATE:
1304 /* Enter a new state. */
1305 sctp_cmd_new_state(commands, asoc, cmd->obj.state);
1306 break;
1307
1308 case SCTP_CMD_REPORT_TSN:
1309 /* Record the arrival of a TSN. */
1310 error = sctp_tsnmap_mark(&asoc->peer.tsn_map,
1311 cmd->obj.u32, NULL);
1312 break;
1313
1314 case SCTP_CMD_REPORT_FWDTSN:
1315 /* Move the Cumulattive TSN Ack ahead. */
1316 sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32);
1317
1318 /* purge the fragmentation queue */
1319 sctp_ulpq_reasm_flushtsn(&asoc->ulpq, cmd->obj.u32);
1320
1321 /* Abort any in progress partial delivery. */
1322 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
1323 break;
1324
1325 case SCTP_CMD_PROCESS_FWDTSN:
1326 sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.chunk);
1327 break;
1328
1329 case SCTP_CMD_GEN_SACK:
1330 /* Generate a Selective ACK.
1331 * The argument tells us whether to just count
1332 * the packet and MAYBE generate a SACK, or
1333 * force a SACK out.
1334 */
1335 force = cmd->obj.i32;
1336 error = sctp_gen_sack(asoc, force, commands);
1337 break;
1338
1339 case SCTP_CMD_PROCESS_SACK:
1340 /* Process an inbound SACK. */
1341 error = sctp_cmd_process_sack(commands, asoc,
1342 cmd->obj.chunk);
1343 break;
1344
1345 case SCTP_CMD_GEN_INIT_ACK:
1346 /* Generate an INIT ACK chunk. */
1347 new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC,
1348 0);
1349 if (!new_obj)
1350 goto nomem;
1351
1352 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1353 SCTP_CHUNK(new_obj));
1354 break;
1355
1356 case SCTP_CMD_PEER_INIT:
1357 /* Process a unified INIT from the peer.
1358 * Note: Only used during INIT-ACK processing. If
1359 * there is an error just return to the outter
1360 * layer which will bail.
1361 */
1362 error = sctp_cmd_process_init(commands, asoc, chunk,
1363 cmd->obj.init, gfp);
1364 break;
1365
1366 case SCTP_CMD_GEN_COOKIE_ECHO:
1367 /* Generate a COOKIE ECHO chunk. */
1368 new_obj = sctp_make_cookie_echo(asoc, chunk);
1369 if (!new_obj) {
1370 if (cmd->obj.chunk)
1371 sctp_chunk_free(cmd->obj.chunk);
1372 goto nomem;
1373 }
1374 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1375 SCTP_CHUNK(new_obj));
1376
1377 /* If there is an ERROR chunk to be sent along with
1378 * the COOKIE_ECHO, send it, too.
1379 */
1380 if (cmd->obj.chunk)
1381 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1382 SCTP_CHUNK(cmd->obj.chunk));
1383
1384 if (new_obj->transport) {
1385 new_obj->transport->init_sent_count++;
1386 asoc->init_last_sent_to = new_obj->transport;
1387 }
1388
1389 /* FIXME - Eventually come up with a cleaner way to
1390 * enabling COOKIE-ECHO + DATA bundling during
1391 * multihoming stale cookie scenarios, the following
1392 * command plays with asoc->peer.retran_path to
1393 * avoid the problem of sending the COOKIE-ECHO and
1394 * DATA in different paths, which could result
1395 * in the association being ABORTed if the DATA chunk
1396 * is processed first by the server. Checking the
1397 * init error counter simply causes this command
1398 * to be executed only during failed attempts of
1399 * association establishment.
1400 */
1401 if ((asoc->peer.retran_path !=
1402 asoc->peer.primary_path) &&
1403 (asoc->init_err_counter > 0)) {
1404 sctp_add_cmd_sf(commands,
1405 SCTP_CMD_FORCE_PRIM_RETRAN,
1406 SCTP_NULL());
1407 }
1408
1409 break;
1410
1411 case SCTP_CMD_GEN_SHUTDOWN:
1412 /* Generate SHUTDOWN when in SHUTDOWN_SENT state.
1413 * Reset error counts.
1414 */
1415 asoc->overall_error_count = 0;
1416
1417 /* Generate a SHUTDOWN chunk. */
1418 new_obj = sctp_make_shutdown(asoc, chunk);
1419 if (!new_obj)
1420 goto nomem;
1421 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1422 SCTP_CHUNK(new_obj));
1423 break;
1424
1425 case SCTP_CMD_CHUNK_ULP:
1426 /* Send a chunk to the sockets layer. */
1427 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1428 "chunk_up:", cmd->obj.chunk,
1429 "ulpq:", &asoc->ulpq);
1430 sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.chunk,
1431 GFP_ATOMIC);
1432 break;
1433
1434 case SCTP_CMD_EVENT_ULP:
1435 /* Send a notification to the sockets layer. */
1436 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1437 "event_up:",cmd->obj.ulpevent,
1438 "ulpq:",&asoc->ulpq);
1439 sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ulpevent);
1440 break;
1441
1442 case SCTP_CMD_REPLY:
1443 /* If an caller has not already corked, do cork. */
1444 if (!asoc->outqueue.cork) {
1445 sctp_outq_cork(&asoc->outqueue);
1446 local_cork = 1;
1447 }
1448 /* Send a chunk to our peer. */
1449 error = sctp_outq_tail(&asoc->outqueue, cmd->obj.chunk);
1450 break;
1451
1452 case SCTP_CMD_SEND_PKT:
1453 /* Send a full packet to our peer. */
1454 packet = cmd->obj.packet;
1455 sctp_packet_transmit(packet);
1456 sctp_ootb_pkt_free(packet);
1457 break;
1458
1459 case SCTP_CMD_T1_RETRAN:
1460 /* Mark a transport for retransmission. */
1461 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1462 SCTP_RTXR_T1_RTX);
1463 break;
1464
1465 case SCTP_CMD_RETRAN:
1466 /* Mark a transport for retransmission. */
1467 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1468 SCTP_RTXR_T3_RTX);
1469 break;
1470
1471 case SCTP_CMD_ECN_CE:
1472 /* Do delayed CE processing. */
1473 sctp_do_ecn_ce_work(asoc, cmd->obj.u32);
1474 break;
1475
1476 case SCTP_CMD_ECN_ECNE:
1477 /* Do delayed ECNE processing. */
1478 new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32,
1479 chunk);
1480 if (new_obj)
1481 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1482 SCTP_CHUNK(new_obj));
1483 break;
1484
1485 case SCTP_CMD_ECN_CWR:
1486 /* Do delayed CWR processing. */
1487 sctp_do_ecn_cwr_work(asoc, cmd->obj.u32);
1488 break;
1489
1490 case SCTP_CMD_SETUP_T2:
1491 sctp_cmd_setup_t2(commands, asoc, cmd->obj.chunk);
1492 break;
1493
1494 case SCTP_CMD_TIMER_START_ONCE:
1495 timer = &asoc->timers[cmd->obj.to];
1496
1497 if (timer_pending(timer))
1498 break;
1499 /* fall through */
1500
1501 case SCTP_CMD_TIMER_START:
1502 timer = &asoc->timers[cmd->obj.to];
1503 timeout = asoc->timeouts[cmd->obj.to];
1504 BUG_ON(!timeout);
1505
1506 timer->expires = jiffies + timeout;
1507 sctp_association_hold(asoc);
1508 add_timer(timer);
1509 break;
1510
1511 case SCTP_CMD_TIMER_RESTART:
1512 timer = &asoc->timers[cmd->obj.to];
1513 timeout = asoc->timeouts[cmd->obj.to];
1514 if (!mod_timer(timer, jiffies + timeout))
1515 sctp_association_hold(asoc);
1516 break;
1517
1518 case SCTP_CMD_TIMER_STOP:
1519 timer = &asoc->timers[cmd->obj.to];
1520 if (timer_pending(timer) && del_timer(timer))
1521 sctp_association_put(asoc);
1522 break;
1523
1524 case SCTP_CMD_INIT_CHOOSE_TRANSPORT:
1525 chunk = cmd->obj.chunk;
1526 t = sctp_assoc_choose_alter_transport(asoc,
1527 asoc->init_last_sent_to);
1528 asoc->init_last_sent_to = t;
1529 chunk->transport = t;
1530 t->init_sent_count++;
1531 /* Set the new transport as primary */
1532 sctp_assoc_set_primary(asoc, t);
1533 break;
1534
1535 case SCTP_CMD_INIT_RESTART:
1536 /* Do the needed accounting and updates
1537 * associated with restarting an initialization
1538 * timer. Only multiply the timeout by two if
1539 * all transports have been tried at the current
1540 * timeout.
1541 */
1542 sctp_cmd_t1_timer_update(asoc,
1543 SCTP_EVENT_TIMEOUT_T1_INIT,
1544 "INIT");
1545
1546 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
1547 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
1548 break;
1549
1550 case SCTP_CMD_COOKIEECHO_RESTART:
1551 /* Do the needed accounting and updates
1552 * associated with restarting an initialization
1553 * timer. Only multiply the timeout by two if
1554 * all transports have been tried at the current
1555 * timeout.
1556 */
1557 sctp_cmd_t1_timer_update(asoc,
1558 SCTP_EVENT_TIMEOUT_T1_COOKIE,
1559 "COOKIE");
1560
1561 /* If we've sent any data bundled with
1562 * COOKIE-ECHO we need to resend.
1563 */
1564 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1565 transports) {
1566 sctp_retransmit_mark(&asoc->outqueue, t,
1567 SCTP_RTXR_T1_RTX);
1568 }
1569
1570 sctp_add_cmd_sf(commands,
1571 SCTP_CMD_TIMER_RESTART,
1572 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
1573 break;
1574
1575 case SCTP_CMD_INIT_FAILED:
1576 sctp_cmd_init_failed(commands, asoc, cmd->obj.err);
1577 break;
1578
1579 case SCTP_CMD_ASSOC_FAILED:
1580 sctp_cmd_assoc_failed(commands, asoc, event_type,
1581 subtype, chunk, cmd->obj.err);
1582 break;
1583
1584 case SCTP_CMD_INIT_COUNTER_INC:
1585 asoc->init_err_counter++;
1586 break;
1587
1588 case SCTP_CMD_INIT_COUNTER_RESET:
1589 asoc->init_err_counter = 0;
1590 asoc->init_cycle = 0;
1591 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1592 transports) {
1593 t->init_sent_count = 0;
1594 }
1595 break;
1596
1597 case SCTP_CMD_REPORT_DUP:
1598 sctp_tsnmap_mark_dup(&asoc->peer.tsn_map,
1599 cmd->obj.u32);
1600 break;
1601
1602 case SCTP_CMD_REPORT_BAD_TAG:
1603 SCTP_DEBUG_PRINTK("vtag mismatch!\n");
1604 break;
1605
1606 case SCTP_CMD_STRIKE:
1607 /* Mark one strike against a transport. */
1608 sctp_do_8_2_transport_strike(commands, asoc,
1609 cmd->obj.transport, 0);
1610 break;
1611
1612 case SCTP_CMD_TRANSPORT_IDLE:
1613 t = cmd->obj.transport;
1614 sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE);
1615 break;
1616
1617 case SCTP_CMD_TRANSPORT_HB_SENT:
1618 t = cmd->obj.transport;
1619 sctp_do_8_2_transport_strike(commands, asoc,
1620 t, 1);
1621 t->hb_sent = 1;
1622 break;
1623
1624 case SCTP_CMD_TRANSPORT_ON:
1625 t = cmd->obj.transport;
1626 sctp_cmd_transport_on(commands, asoc, t, chunk);
1627 break;
1628
1629 case SCTP_CMD_HB_TIMERS_START:
1630 sctp_cmd_hb_timers_start(commands, asoc);
1631 break;
1632
1633 case SCTP_CMD_HB_TIMER_UPDATE:
1634 t = cmd->obj.transport;
1635 sctp_cmd_hb_timer_update(commands, t);
1636 break;
1637
1638 case SCTP_CMD_HB_TIMERS_STOP:
1639 sctp_cmd_hb_timers_stop(commands, asoc);
1640 break;
1641
1642 case SCTP_CMD_REPORT_ERROR:
1643 error = cmd->obj.error;
1644 break;
1645
1646 case SCTP_CMD_PROCESS_CTSN:
1647 /* Dummy up a SACK for processing. */
1648 sackh.cum_tsn_ack = cmd->obj.be32;
1649 sackh.a_rwnd = asoc->peer.rwnd +
1650 asoc->outqueue.outstanding_bytes;
1651 sackh.num_gap_ack_blocks = 0;
1652 sackh.num_dup_tsns = 0;
1653 chunk->subh.sack_hdr = &sackh;
1654 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK,
1655 SCTP_CHUNK(chunk));
1656 break;
1657
1658 case SCTP_CMD_DISCARD_PACKET:
1659 /* We need to discard the whole packet.
1660 * Uncork the queue since there might be
1661 * responses pending
1662 */
1663 chunk->pdiscard = 1;
1664 if (asoc) {
1665 sctp_outq_uncork(&asoc->outqueue);
1666 local_cork = 0;
1667 }
1668 break;
1669
1670 case SCTP_CMD_RTO_PENDING:
1671 t = cmd->obj.transport;
1672 t->rto_pending = 1;
1673 break;
1674
1675 case SCTP_CMD_PART_DELIVER:
1676 sctp_ulpq_partial_delivery(&asoc->ulpq, GFP_ATOMIC);
1677 break;
1678
1679 case SCTP_CMD_RENEGE:
1680 sctp_ulpq_renege(&asoc->ulpq, cmd->obj.chunk,
1681 GFP_ATOMIC);
1682 break;
1683
1684 case SCTP_CMD_SETUP_T4:
1685 sctp_cmd_setup_t4(commands, asoc, cmd->obj.chunk);
1686 break;
1687
1688 case SCTP_CMD_PROCESS_OPERR:
1689 sctp_cmd_process_operr(commands, asoc, chunk);
1690 break;
1691 case SCTP_CMD_CLEAR_INIT_TAG:
1692 asoc->peer.i.init_tag = 0;
1693 break;
1694 case SCTP_CMD_DEL_NON_PRIMARY:
1695 sctp_cmd_del_non_primary(asoc);
1696 break;
1697 case SCTP_CMD_T3_RTX_TIMERS_STOP:
1698 sctp_cmd_t3_rtx_timers_stop(commands, asoc);
1699 break;
1700 case SCTP_CMD_FORCE_PRIM_RETRAN:
1701 t = asoc->peer.retran_path;
1702 asoc->peer.retran_path = asoc->peer.primary_path;
1703 error = sctp_outq_uncork(&asoc->outqueue);
1704 local_cork = 0;
1705 asoc->peer.retran_path = t;
1706 break;
1707 case SCTP_CMD_SET_SK_ERR:
1708 sctp_cmd_set_sk_err(asoc, cmd->obj.error);
1709 break;
1710 case SCTP_CMD_ASSOC_CHANGE:
1711 sctp_cmd_assoc_change(commands, asoc,
1712 cmd->obj.u8);
1713 break;
1714 case SCTP_CMD_ADAPTATION_IND:
1715 sctp_cmd_adaptation_ind(commands, asoc);
1716 break;
1717
1718 case SCTP_CMD_ASSOC_SHKEY:
1719 error = sctp_auth_asoc_init_active_key(asoc,
1720 GFP_ATOMIC);
1721 break;
1722 case SCTP_CMD_UPDATE_INITTAG:
1723 asoc->peer.i.init_tag = cmd->obj.u32;
1724 break;
1725 case SCTP_CMD_SEND_MSG:
1726 if (!asoc->outqueue.cork) {
1727 sctp_outq_cork(&asoc->outqueue);
1728 local_cork = 1;
1729 }
1730 error = sctp_cmd_send_msg(asoc, cmd->obj.msg);
1731 break;
1732 case SCTP_CMD_SEND_NEXT_ASCONF:
1733 sctp_cmd_send_asconf(asoc);
1734 break;
1735 case SCTP_CMD_PURGE_ASCONF_QUEUE:
1736 sctp_asconf_queue_teardown(asoc);
1737 break;
1738
1739 case SCTP_CMD_SET_ASOC:
1740 asoc = cmd->obj.asoc;
1741 break;
1742
1743 default:
1744 pr_warn("Impossible command: %u\n",
1745 cmd->verb);
1746 break;
1747 }
1748
1749 if (error)
1750 break;
1751 }
1752
1753 out:
1754 /* If this is in response to a received chunk, wait until
1755 * we are done with the packet to open the queue so that we don't
1756 * send multiple packets in response to a single request.
1757 */
1758 if (asoc && SCTP_EVENT_T_CHUNK == event_type && chunk) {
1759 if (chunk->end_of_packet || chunk->singleton)
1760 error = sctp_outq_uncork(&asoc->outqueue);
1761 } else if (local_cork)
1762 error = sctp_outq_uncork(&asoc->outqueue);
1763 return error;
1764 nomem:
1765 error = -ENOMEM;
1766 goto out;
1767 }
1768
CRIS linux kernel tree