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.
7 * This file is part of the SCTP kernel implementation
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.
13 * Please send any bug reports or fixes you make to the
15 * lksctp developers <linux-sctp@vger.kernel.org>
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>
28 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
30 #include <linux/skbuff.h>
31 #include <linux/types.h>
32 #include <linux/socket.h>
34 #include <linux/gfp.h>
36 #include <net/sctp/sctp.h>
37 #include <net/sctp/sm.h>
38 #include <net/sctp/stream_sched.h>
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,
46 enum sctp_disposition status,
47 struct sctp_cmd_seq *commands,
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,
55 enum sctp_disposition status,
56 struct sctp_cmd_seq *commands,
59 /********************************************************************
61 ********************************************************************/
63 /* A helper function for delayed processing of INET ECN CE bit. */
64 static void sctp_do_ecn_ce_work(struct sctp_association *asoc,
67 /* Save the TSN away for comparison when we receive CWR */
69 asoc->last_ecne_tsn = lowest_tsn;
73 /* Helper function for delayed processing of SCTP ECNE chunk. */
74 /* RFC 2960 Appendix A
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.
85 static struct sctp_chunk *sctp_do_ecn_ecne_work(struct sctp_association *asoc,
87 struct sctp_chunk *chunk)
89 struct sctp_chunk *repl;
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
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.
101 if (TSN_lt(asoc->last_cwr_tsn, lowest_tsn)) {
102 struct sctp_transport *transport;
104 /* Find which transport's congestion variables
105 * need to be adjusted.
107 transport = sctp_assoc_lookup_tsn(asoc, lowest_tsn);
109 /* Update the congestion variables. */
111 sctp_transport_lower_cwnd(transport,
112 SCTP_LOWER_CWND_ECNE);
113 asoc->last_cwr_tsn = lowest_tsn;
116 /* Always try to quiet the other end. In case of lost CWR,
117 * resend last_cwr_tsn.
119 repl = sctp_make_cwr(asoc, asoc->last_cwr_tsn, chunk);
121 /* If we run out of memory, it will look like a lost CWR. We'll
122 * get back in sync eventually.
127 /* Helper function to do delayed processing of ECN CWR chunk. */
128 static void sctp_do_ecn_cwr_work(struct sctp_association *asoc,
131 /* Turn off ECNE getting auto-prepended to every outgoing
137 /* Generate SACK if necessary. We call this at the end of a packet. */
138 static int sctp_gen_sack(struct sctp_association *asoc, int force,
139 struct sctp_cmd_seq *commands)
141 struct sctp_transport *trans = asoc->peer.last_data_from;
142 __u32 ctsn, max_tsn_seen;
143 struct sctp_chunk *sack;
147 (!trans && (asoc->param_flags & SPP_SACKDELAY_DISABLE)) ||
148 (trans && (trans->param_flags & SPP_SACKDELAY_DISABLE)))
149 asoc->peer.sack_needed = 1;
151 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
152 max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
154 /* From 12.2 Parameters necessary per association (i.e. the TCB):
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).
161 * [This is actually not mentioned in Section 6, but we
162 * implement it here anyway. --piggy]
164 if (max_tsn_seen != ctsn)
165 asoc->peer.sack_needed = 1;
167 /* From 6.2 Acknowledgement on Reception of DATA Chunks:
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. ...
175 if (!asoc->peer.sack_needed) {
176 asoc->peer.sack_cnt++;
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.
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;
188 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
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;
195 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
199 /* Restart the SACK timer. */
200 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
201 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
203 __u32 old_a_rwnd = asoc->a_rwnd;
205 asoc->a_rwnd = asoc->rwnd;
206 sack = sctp_make_sack(asoc);
208 asoc->a_rwnd = old_a_rwnd;
212 asoc->peer.sack_needed = 0;
213 asoc->peer.sack_cnt = 0;
215 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(sack));
217 /* Stop the SACK timer. */
218 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
219 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
228 /* When the T3-RTX timer expires, it calls this function to create the
229 * relevant state machine event.
231 void sctp_generate_t3_rtx_event(struct timer_list *t)
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);
240 /* Check whether a task is in the sock. */
243 if (sock_owned_by_user(sk)) {
244 pr_debug("%s: sock is busy\n", __func__);
246 /* Try again later. */
247 if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20)))
248 sctp_transport_hold(transport);
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),
257 transport, GFP_ATOMIC);
264 sctp_transport_put(transport);
267 /* This is a sa interface for producing timeout events. It works
268 * for timeouts which use the association as their parameter.
270 static void sctp_generate_timeout_event(struct sctp_association *asoc,
271 enum sctp_event_timeout timeout_type)
273 struct sock *sk = asoc->base.sk;
274 struct net *net = sock_net(sk);
278 if (sock_owned_by_user(sk)) {
279 pr_debug("%s: sock is busy: timer %d\n", __func__,
282 /* Try again later. */
283 if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20)))
284 sctp_association_hold(asoc);
288 /* Is this association really dead and just waiting around for
289 * the timer to let go of the reference?
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);
305 sctp_association_put(asoc);
308 static void sctp_generate_t1_cookie_event(struct timer_list *t)
310 struct sctp_association *asoc =
311 from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_T1_COOKIE]);
313 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE);
316 static void sctp_generate_t1_init_event(struct timer_list *t)
318 struct sctp_association *asoc =
319 from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_T1_INIT]);
321 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT);
324 static void sctp_generate_t2_shutdown_event(struct timer_list *t)
326 struct sctp_association *asoc =
327 from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN]);
329 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN);
332 static void sctp_generate_t4_rto_event(struct timer_list *t)
334 struct sctp_association *asoc =
335 from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_T4_RTO]);
337 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO);
340 static void sctp_generate_t5_shutdown_guard_event(struct timer_list *t)
342 struct sctp_association *asoc =
344 timers[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD]);
346 sctp_generate_timeout_event(asoc,
347 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD);
349 } /* sctp_generate_t5_shutdown_guard_event() */
351 static void sctp_generate_autoclose_event(struct timer_list *t)
353 struct sctp_association *asoc =
354 from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_AUTOCLOSE]);
356 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE);
359 /* Generate a heart beat event. If the sock is busy, reschedule. Make
360 * sure that the transport is still valid.
362 void sctp_generate_heartbeat_event(struct timer_list *t)
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;
372 if (sock_owned_by_user(sk)) {
373 pr_debug("%s: sock is busy\n", __func__);
375 /* Try again later. */
376 if (!mod_timer(&transport->hb_timer, jiffies + (HZ/20)))
377 sctp_transport_hold(transport);
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);
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);
401 sctp_transport_put(transport);
404 /* Handle the timeout of the ICMP protocol unreachable timer. Trigger
405 * the correct state machine transition that will close the association.
407 void sctp_generate_proto_unreach_event(struct timer_list *t)
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);
416 if (sock_owned_by_user(sk)) {
417 pr_debug("%s: sock is busy\n", __func__);
419 /* Try again later. */
420 if (!mod_timer(&transport->proto_unreach_timer,
422 sctp_association_hold(asoc);
426 /* Is this structure just waiting around for us to actually
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);
438 sctp_association_put(asoc);
441 /* Handle the timeout of the RE-CONFIG timer. */
442 void sctp_generate_reconf_event(struct timer_list *t)
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);
452 if (sock_owned_by_user(sk)) {
453 pr_debug("%s: sock is busy\n", __func__);
455 /* Try again later. */
456 if (!mod_timer(&transport->reconf_timer, jiffies + (HZ / 20)))
457 sctp_transport_hold(transport);
461 error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
462 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_RECONF),
463 asoc->state, asoc->ep, asoc,
464 transport, GFP_ATOMIC);
471 sctp_transport_put(transport);
474 /* Inject a SACK Timeout event into the state machine. */
475 static void sctp_generate_sack_event(struct timer_list *t)
477 struct sctp_association *asoc =
478 from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_SACK]);
480 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK);
483 sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = {
484 [SCTP_EVENT_TIMEOUT_NONE] = NULL,
485 [SCTP_EVENT_TIMEOUT_T1_COOKIE] = sctp_generate_t1_cookie_event,
486 [SCTP_EVENT_TIMEOUT_T1_INIT] = sctp_generate_t1_init_event,
487 [SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = sctp_generate_t2_shutdown_event,
488 [SCTP_EVENT_TIMEOUT_T3_RTX] = NULL,
489 [SCTP_EVENT_TIMEOUT_T4_RTO] = sctp_generate_t4_rto_event,
490 [SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD] =
491 sctp_generate_t5_shutdown_guard_event,
492 [SCTP_EVENT_TIMEOUT_HEARTBEAT] = NULL,
493 [SCTP_EVENT_TIMEOUT_RECONF] = NULL,
494 [SCTP_EVENT_TIMEOUT_SACK] = sctp_generate_sack_event,
495 [SCTP_EVENT_TIMEOUT_AUTOCLOSE] = sctp_generate_autoclose_event,
499 /* RFC 2960 8.2 Path Failure Detection
501 * When its peer endpoint is multi-homed, an endpoint should keep a
502 * error counter for each of the destination transport addresses of the
505 * Each time the T3-rtx timer expires on any address, or when a
506 * HEARTBEAT sent to an idle address is not acknowledged within a RTO,
507 * the error counter of that destination address will be incremented.
508 * When the value in the error counter exceeds the protocol parameter
509 * 'Path.Max.Retrans' of that destination address, the endpoint should
510 * mark the destination transport address as inactive, and a
511 * notification SHOULD be sent to the upper layer.
514 static void sctp_do_8_2_transport_strike(struct sctp_cmd_seq *commands,
515 struct sctp_association *asoc,
516 struct sctp_transport *transport,
519 struct net *net = sock_net(asoc->base.sk);
521 /* The check for association's overall error counter exceeding the
522 * threshold is done in the state function.
524 /* We are here due to a timer expiration. If the timer was
525 * not a HEARTBEAT, then normal error tracking is done.
526 * If the timer was a heartbeat, we only increment error counts
527 * when we already have an outstanding HEARTBEAT that has not
529 * Additionally, some tranport states inhibit error increments.
532 asoc->overall_error_count++;
533 if (transport->state != SCTP_INACTIVE)
534 transport->error_count++;
535 } else if (transport->hb_sent) {
536 if (transport->state != SCTP_UNCONFIRMED)
537 asoc->overall_error_count++;
538 if (transport->state != SCTP_INACTIVE)
539 transport->error_count++;
542 /* If the transport error count is greater than the pf_retrans
543 * threshold, and less than pathmaxrtx, and if the current state
544 * is SCTP_ACTIVE, then mark this transport as Partially Failed,
545 * see SCTP Quick Failover Draft, section 5.1
547 if (net->sctp.pf_enable &&
548 (transport->state == SCTP_ACTIVE) &&
549 (transport->error_count < transport->pathmaxrxt) &&
550 (transport->error_count > transport->pf_retrans)) {
552 sctp_assoc_control_transport(asoc, transport,
556 /* Update the hb timer to resend a heartbeat every rto */
557 sctp_transport_reset_hb_timer(transport);
560 if (transport->state != SCTP_INACTIVE &&
561 (transport->error_count > transport->pathmaxrxt)) {
562 pr_debug("%s: association:%p transport addr:%pISpc failed\n",
563 __func__, asoc, &transport->ipaddr.sa);
565 sctp_assoc_control_transport(asoc, transport,
567 SCTP_FAILED_THRESHOLD);
570 if (transport->error_count > transport->ps_retrans &&
571 asoc->peer.primary_path == transport &&
572 asoc->peer.active_path != transport)
573 sctp_assoc_set_primary(asoc, asoc->peer.active_path);
575 /* E2) For the destination address for which the timer
576 * expires, set RTO <- RTO * 2 ("back off the timer"). The
577 * maximum value discussed in rule C7 above (RTO.max) may be
578 * used to provide an upper bound to this doubling operation.
580 * Special Case: the first HB doesn't trigger exponential backoff.
581 * The first unacknowledged HB triggers it. We do this with a flag
582 * that indicates that we have an outstanding HB.
584 if (!is_hb || transport->hb_sent) {
585 transport->rto = min((transport->rto * 2), transport->asoc->rto_max);
586 sctp_max_rto(asoc, transport);
590 /* Worker routine to handle INIT command failure. */
591 static void sctp_cmd_init_failed(struct sctp_cmd_seq *commands,
592 struct sctp_association *asoc,
595 struct sctp_ulpevent *event;
597 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_CANT_STR_ASSOC,
598 (__u16)error, 0, 0, NULL,
602 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
603 SCTP_ULPEVENT(event));
605 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
606 SCTP_STATE(SCTP_STATE_CLOSED));
608 /* SEND_FAILED sent later when cleaning up the association. */
609 asoc->outqueue.error = error;
610 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
613 /* Worker routine to handle SCTP_CMD_ASSOC_FAILED. */
614 static void sctp_cmd_assoc_failed(struct sctp_cmd_seq *commands,
615 struct sctp_association *asoc,
616 enum sctp_event_type event_type,
617 union sctp_subtype subtype,
618 struct sctp_chunk *chunk,
621 struct sctp_ulpevent *event;
622 struct sctp_chunk *abort;
624 /* Cancel any partial delivery in progress. */
625 asoc->stream.si->abort_pd(&asoc->ulpq, GFP_ATOMIC);
627 if (event_type == SCTP_EVENT_T_CHUNK && subtype.chunk == SCTP_CID_ABORT)
628 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
629 (__u16)error, 0, 0, chunk,
632 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
633 (__u16)error, 0, 0, NULL,
636 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
637 SCTP_ULPEVENT(event));
639 if (asoc->overall_error_count >= asoc->max_retrans) {
640 abort = sctp_make_violation_max_retrans(asoc, chunk);
642 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
646 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
647 SCTP_STATE(SCTP_STATE_CLOSED));
649 /* SEND_FAILED sent later when cleaning up the association. */
650 asoc->outqueue.error = error;
651 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
654 /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT
655 * inside the cookie. In reality, this is only used for INIT-ACK processing
656 * since all other cases use "temporary" associations and can do all
657 * their work in statefuns directly.
659 static int sctp_cmd_process_init(struct sctp_cmd_seq *commands,
660 struct sctp_association *asoc,
661 struct sctp_chunk *chunk,
662 struct sctp_init_chunk *peer_init,
667 /* We only process the init as a sideeffect in a single
668 * case. This is when we process the INIT-ACK. If we
669 * fail during INIT processing (due to malloc problems),
670 * just return the error and stop processing the stack.
672 if (!sctp_process_init(asoc, chunk, sctp_source(chunk), peer_init, gfp))
680 /* Helper function to break out starting up of heartbeat timers. */
681 static void sctp_cmd_hb_timers_start(struct sctp_cmd_seq *cmds,
682 struct sctp_association *asoc)
684 struct sctp_transport *t;
686 /* Start a heartbeat timer for each transport on the association.
687 * hold a reference on the transport to make sure none of
688 * the needed data structures go away.
690 list_for_each_entry(t, &asoc->peer.transport_addr_list, transports)
691 sctp_transport_reset_hb_timer(t);
694 static void sctp_cmd_hb_timers_stop(struct sctp_cmd_seq *cmds,
695 struct sctp_association *asoc)
697 struct sctp_transport *t;
699 /* Stop all heartbeat timers. */
701 list_for_each_entry(t, &asoc->peer.transport_addr_list,
703 if (del_timer(&t->hb_timer))
704 sctp_transport_put(t);
708 /* Helper function to stop any pending T3-RTX timers */
709 static void sctp_cmd_t3_rtx_timers_stop(struct sctp_cmd_seq *cmds,
710 struct sctp_association *asoc)
712 struct sctp_transport *t;
714 list_for_each_entry(t, &asoc->peer.transport_addr_list,
716 if (del_timer(&t->T3_rtx_timer))
717 sctp_transport_put(t);
722 /* Helper function to handle the reception of an HEARTBEAT ACK. */
723 static void sctp_cmd_transport_on(struct sctp_cmd_seq *cmds,
724 struct sctp_association *asoc,
725 struct sctp_transport *t,
726 struct sctp_chunk *chunk)
728 struct sctp_sender_hb_info *hbinfo;
729 int was_unconfirmed = 0;
731 /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the
732 * HEARTBEAT should clear the error counter of the destination
733 * transport address to which the HEARTBEAT was sent.
738 * Although RFC4960 specifies that the overall error count must
739 * be cleared when a HEARTBEAT ACK is received, we make an
740 * exception while in SHUTDOWN PENDING. If the peer keeps its
741 * window shut forever, we may never be able to transmit our
742 * outstanding data and rely on the retransmission limit be reached
743 * to shutdown the association.
745 if (t->asoc->state < SCTP_STATE_SHUTDOWN_PENDING)
746 t->asoc->overall_error_count = 0;
748 /* Clear the hb_sent flag to signal that we had a good
753 /* Mark the destination transport address as active if it is not so
756 if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED)) {
758 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
759 SCTP_HEARTBEAT_SUCCESS);
762 if (t->state == SCTP_PF)
763 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
764 SCTP_HEARTBEAT_SUCCESS);
766 /* HB-ACK was received for a the proper HB. Consider this
770 sctp_transport_dst_confirm(t);
772 /* The receiver of the HEARTBEAT ACK should also perform an
773 * RTT measurement for that destination transport address
774 * using the time value carried in the HEARTBEAT ACK chunk.
775 * If the transport's rto_pending variable has been cleared,
776 * it was most likely due to a retransmit. However, we want
777 * to re-enable it to properly update the rto.
779 if (t->rto_pending == 0)
782 hbinfo = (struct sctp_sender_hb_info *)chunk->skb->data;
783 sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at));
785 /* Update the heartbeat timer. */
786 sctp_transport_reset_hb_timer(t);
788 if (was_unconfirmed && asoc->peer.transport_count == 1)
789 sctp_transport_immediate_rtx(t);
793 /* Helper function to process the process SACK command. */
794 static int sctp_cmd_process_sack(struct sctp_cmd_seq *cmds,
795 struct sctp_association *asoc,
796 struct sctp_chunk *chunk)
800 if (sctp_outq_sack(&asoc->outqueue, chunk)) {
801 struct net *net = sock_net(asoc->base.sk);
803 /* There are no more TSNs awaiting SACK. */
804 err = sctp_do_sm(net, SCTP_EVENT_T_OTHER,
805 SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN),
806 asoc->state, asoc->ep, asoc, NULL,
813 /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set
814 * the transport for a shutdown chunk.
816 static void sctp_cmd_setup_t2(struct sctp_cmd_seq *cmds,
817 struct sctp_association *asoc,
818 struct sctp_chunk *chunk)
820 struct sctp_transport *t;
822 if (chunk->transport)
823 t = chunk->transport;
825 t = sctp_assoc_choose_alter_transport(asoc,
826 asoc->shutdown_last_sent_to);
827 chunk->transport = t;
829 asoc->shutdown_last_sent_to = t;
830 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto;
833 static void sctp_cmd_assoc_update(struct sctp_cmd_seq *cmds,
834 struct sctp_association *asoc,
835 struct sctp_association *new)
837 struct net *net = sock_net(asoc->base.sk);
838 struct sctp_chunk *abort;
840 if (!sctp_assoc_update(asoc, new))
843 abort = sctp_make_abort(asoc, NULL, sizeof(struct sctp_errhdr));
845 sctp_init_cause(abort, SCTP_ERROR_RSRC_LOW, 0);
846 sctp_add_cmd_sf(cmds, SCTP_CMD_REPLY, SCTP_CHUNK(abort));
848 sctp_add_cmd_sf(cmds, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(ECONNABORTED));
849 sctp_add_cmd_sf(cmds, SCTP_CMD_ASSOC_FAILED,
850 SCTP_PERR(SCTP_ERROR_RSRC_LOW));
851 SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
852 SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
855 /* Helper function to change the state of an association. */
856 static void sctp_cmd_new_state(struct sctp_cmd_seq *cmds,
857 struct sctp_association *asoc,
858 enum sctp_state state)
860 struct sock *sk = asoc->base.sk;
864 pr_debug("%s: asoc:%p[%s]\n", __func__, asoc, sctp_state_tbl[state]);
866 if (sctp_style(sk, TCP)) {
867 /* Change the sk->sk_state of a TCP-style socket that has
868 * successfully completed a connect() call.
870 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED))
871 inet_sk_set_state(sk, SCTP_SS_ESTABLISHED);
873 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */
874 if (sctp_state(asoc, SHUTDOWN_RECEIVED) &&
875 sctp_sstate(sk, ESTABLISHED)) {
876 inet_sk_set_state(sk, SCTP_SS_CLOSING);
877 sk->sk_shutdown |= RCV_SHUTDOWN;
881 if (sctp_state(asoc, COOKIE_WAIT)) {
882 /* Reset init timeouts since they may have been
883 * increased due to timer expirations.
885 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
887 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
891 if (sctp_state(asoc, ESTABLISHED)) {
892 kfree(asoc->peer.cookie);
893 asoc->peer.cookie = NULL;
896 if (sctp_state(asoc, ESTABLISHED) ||
897 sctp_state(asoc, CLOSED) ||
898 sctp_state(asoc, SHUTDOWN_RECEIVED)) {
899 /* Wake up any processes waiting in the asoc's wait queue in
900 * sctp_wait_for_connect() or sctp_wait_for_sndbuf().
902 if (waitqueue_active(&asoc->wait))
903 wake_up_interruptible(&asoc->wait);
905 /* Wake up any processes waiting in the sk's sleep queue of
906 * a TCP-style or UDP-style peeled-off socket in
907 * sctp_wait_for_accept() or sctp_wait_for_packet().
908 * For a UDP-style socket, the waiters are woken up by the
911 if (!sctp_style(sk, UDP))
912 sk->sk_state_change(sk);
915 if (sctp_state(asoc, SHUTDOWN_PENDING) &&
916 !sctp_outq_is_empty(&asoc->outqueue))
917 sctp_outq_uncork(&asoc->outqueue, GFP_ATOMIC);
920 /* Helper function to delete an association. */
921 static void sctp_cmd_delete_tcb(struct sctp_cmd_seq *cmds,
922 struct sctp_association *asoc)
924 struct sock *sk = asoc->base.sk;
926 /* If it is a non-temporary association belonging to a TCP-style
927 * listening socket that is not closed, do not free it so that accept()
928 * can pick it up later.
930 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) &&
931 (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK))
934 sctp_association_free(asoc);
938 * ADDIP Section 4.1 ASCONF Chunk Procedures
939 * A4) Start a T-4 RTO timer, using the RTO value of the selected
940 * destination address (we use active path instead of primary path just
941 * because primary path may be inactive.
943 static void sctp_cmd_setup_t4(struct sctp_cmd_seq *cmds,
944 struct sctp_association *asoc,
945 struct sctp_chunk *chunk)
947 struct sctp_transport *t;
949 t = sctp_assoc_choose_alter_transport(asoc, chunk->transport);
950 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto;
951 chunk->transport = t;
954 /* Process an incoming Operation Error Chunk. */
955 static void sctp_cmd_process_operr(struct sctp_cmd_seq *cmds,
956 struct sctp_association *asoc,
957 struct sctp_chunk *chunk)
959 struct sctp_errhdr *err_hdr;
960 struct sctp_ulpevent *ev;
962 while (chunk->chunk_end > chunk->skb->data) {
963 err_hdr = (struct sctp_errhdr *)(chunk->skb->data);
965 ev = sctp_ulpevent_make_remote_error(asoc, chunk, 0,
970 asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
972 switch (err_hdr->cause) {
973 case SCTP_ERROR_UNKNOWN_CHUNK:
975 struct sctp_chunkhdr *unk_chunk_hdr;
977 unk_chunk_hdr = (struct sctp_chunkhdr *)
979 switch (unk_chunk_hdr->type) {
980 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with
981 * an ERROR chunk reporting that it did not recognized
982 * the ASCONF chunk type, the sender of the ASCONF MUST
983 * NOT send any further ASCONF chunks and MUST stop its
986 case SCTP_CID_ASCONF:
987 if (asoc->peer.asconf_capable == 0)
990 asoc->peer.asconf_capable = 0;
991 sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP,
992 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
1005 /* Helper function to remove the association non-primary peer
1008 static void sctp_cmd_del_non_primary(struct sctp_association *asoc)
1010 struct sctp_transport *t;
1011 struct list_head *temp;
1012 struct list_head *pos;
1014 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1015 t = list_entry(pos, struct sctp_transport, transports);
1016 if (!sctp_cmp_addr_exact(&t->ipaddr,
1017 &asoc->peer.primary_addr)) {
1018 sctp_assoc_rm_peer(asoc, t);
1023 /* Helper function to set sk_err on a 1-1 style socket. */
1024 static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error)
1026 struct sock *sk = asoc->base.sk;
1028 if (!sctp_style(sk, UDP))
1032 /* Helper function to generate an association change event */
1033 static void sctp_cmd_assoc_change(struct sctp_cmd_seq *commands,
1034 struct sctp_association *asoc,
1037 struct sctp_ulpevent *ev;
1039 ev = sctp_ulpevent_make_assoc_change(asoc, 0, state, 0,
1040 asoc->c.sinit_num_ostreams,
1041 asoc->c.sinit_max_instreams,
1044 asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
1047 static void sctp_cmd_peer_no_auth(struct sctp_cmd_seq *commands,
1048 struct sctp_association *asoc)
1050 struct sctp_ulpevent *ev;
1052 ev = sctp_ulpevent_make_authkey(asoc, 0, SCTP_AUTH_NO_AUTH, GFP_ATOMIC);
1054 asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
1057 /* Helper function to generate an adaptation indication event */
1058 static void sctp_cmd_adaptation_ind(struct sctp_cmd_seq *commands,
1059 struct sctp_association *asoc)
1061 struct sctp_ulpevent *ev;
1063 ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC);
1066 asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
1070 static void sctp_cmd_t1_timer_update(struct sctp_association *asoc,
1071 enum sctp_event_timeout timer,
1074 struct sctp_transport *t;
1076 t = asoc->init_last_sent_to;
1077 asoc->init_err_counter++;
1079 if (t->init_sent_count > (asoc->init_cycle + 1)) {
1080 asoc->timeouts[timer] *= 2;
1081 if (asoc->timeouts[timer] > asoc->max_init_timeo) {
1082 asoc->timeouts[timer] = asoc->max_init_timeo;
1086 pr_debug("%s: T1[%s] timeout adjustment init_err_counter:%d"
1087 " cycle:%d timeout:%ld\n", __func__, name,
1088 asoc->init_err_counter, asoc->init_cycle,
1089 asoc->timeouts[timer]);
1094 /* Send the whole message, chunk by chunk, to the outqueue.
1095 * This way the whole message is queued up and bundling if
1096 * encouraged for small fragments.
1098 static void sctp_cmd_send_msg(struct sctp_association *asoc,
1099 struct sctp_datamsg *msg, gfp_t gfp)
1101 struct sctp_chunk *chunk;
1103 list_for_each_entry(chunk, &msg->chunks, frag_list)
1104 sctp_outq_tail(&asoc->outqueue, chunk, gfp);
1106 asoc->outqueue.sched->enqueue(&asoc->outqueue, msg);
1110 /* These three macros allow us to pull the debugging code out of the
1111 * main flow of sctp_do_sm() to keep attention focused on the real
1112 * functionality there.
1114 #define debug_pre_sfn() \
1115 pr_debug("%s[pre-fn]: ep:%p, %s, %s, asoc:%p[%s], %s\n", __func__, \
1116 ep, sctp_evttype_tbl[event_type], (*debug_fn)(subtype), \
1117 asoc, sctp_state_tbl[state], state_fn->name)
1119 #define debug_post_sfn() \
1120 pr_debug("%s[post-fn]: asoc:%p, status:%s\n", __func__, asoc, \
1121 sctp_status_tbl[status])
1123 #define debug_post_sfx() \
1124 pr_debug("%s[post-sfx]: error:%d, asoc:%p[%s]\n", __func__, error, \
1125 asoc, sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \
1126 sctp_assoc2id(asoc))) ? asoc->state : SCTP_STATE_CLOSED])
1129 * This is the master state machine processing function.
1131 * If you want to understand all of lksctp, this is a
1132 * good place to start.
1134 int sctp_do_sm(struct net *net, enum sctp_event_type event_type,
1135 union sctp_subtype subtype, enum sctp_state state,
1136 struct sctp_endpoint *ep, struct sctp_association *asoc,
1137 void *event_arg, gfp_t gfp)
1139 typedef const char *(printfn_t)(union sctp_subtype);
1140 static printfn_t *table[] = {
1141 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname,
1143 printfn_t *debug_fn __attribute__ ((unused)) = table[event_type];
1144 const struct sctp_sm_table_entry *state_fn;
1145 struct sctp_cmd_seq commands;
1146 enum sctp_disposition status;
1149 /* Look up the state function, run it, and then process the
1150 * side effects. These three steps are the heart of lksctp.
1152 state_fn = sctp_sm_lookup_event(net, event_type, state, subtype);
1154 sctp_init_cmd_seq(&commands);
1157 status = state_fn->fn(net, ep, asoc, subtype, event_arg, &commands);
1160 error = sctp_side_effects(event_type, subtype, state,
1161 ep, &asoc, event_arg, status,
1168 /*****************************************************************
1169 * This the master state function side effect processing function.
1170 *****************************************************************/
1171 static int sctp_side_effects(enum sctp_event_type event_type,
1172 union sctp_subtype subtype,
1173 enum sctp_state state,
1174 struct sctp_endpoint *ep,
1175 struct sctp_association **asoc,
1177 enum sctp_disposition status,
1178 struct sctp_cmd_seq *commands,
1183 /* FIXME - Most of the dispositions left today would be categorized
1184 * as "exceptional" dispositions. For those dispositions, it
1185 * may not be proper to run through any of the commands at all.
1186 * For example, the command interpreter might be run only with
1187 * disposition SCTP_DISPOSITION_CONSUME.
1189 if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state,
1196 case SCTP_DISPOSITION_DISCARD:
1197 pr_debug("%s: ignored sctp protocol event - state:%d, "
1198 "event_type:%d, event_id:%d\n", __func__, state,
1199 event_type, subtype.chunk);
1202 case SCTP_DISPOSITION_NOMEM:
1203 /* We ran out of memory, so we need to discard this
1206 /* BUG--we should now recover some memory, probably by
1212 case SCTP_DISPOSITION_DELETE_TCB:
1213 case SCTP_DISPOSITION_ABORT:
1214 /* This should now be a command. */
1218 case SCTP_DISPOSITION_CONSUME:
1220 * We should no longer have much work to do here as the
1221 * real work has been done as explicit commands above.
1225 case SCTP_DISPOSITION_VIOLATION:
1226 net_err_ratelimited("protocol violation state %d chunkid %d\n",
1227 state, subtype.chunk);
1230 case SCTP_DISPOSITION_NOT_IMPL:
1231 pr_warn("unimplemented feature in state %d, event_type %d, event_id %d\n",
1232 state, event_type, subtype.chunk);
1235 case SCTP_DISPOSITION_BUG:
1236 pr_err("bug in state %d, event_type %d, event_id %d\n",
1237 state, event_type, subtype.chunk);
1242 pr_err("impossible disposition %d in state %d, event_type %d, event_id %d\n",
1243 status, state, event_type, subtype.chunk);
1252 /********************************************************************
1253 * 2nd Level Abstractions
1254 ********************************************************************/
1256 /* This is the side-effect interpreter. */
1257 static int sctp_cmd_interpreter(enum sctp_event_type event_type,
1258 union sctp_subtype subtype,
1259 enum sctp_state state,
1260 struct sctp_endpoint *ep,
1261 struct sctp_association *asoc,
1263 enum sctp_disposition status,
1264 struct sctp_cmd_seq *commands,
1267 struct sctp_sock *sp = sctp_sk(ep->base.sk);
1268 struct sctp_chunk *chunk = NULL, *new_obj;
1269 struct sctp_packet *packet;
1270 struct sctp_sackhdr sackh;
1271 struct timer_list *timer;
1272 struct sctp_transport *t;
1273 unsigned long timeout;
1274 struct sctp_cmd *cmd;
1279 if (SCTP_EVENT_T_TIMEOUT != event_type)
1282 /* Note: This whole file is a huge candidate for rework.
1283 * For example, each command could either have its own handler, so
1284 * the loop would look like:
1286 * cmd->handle(x, y, z)
1289 while (NULL != (cmd = sctp_next_cmd(commands))) {
1290 switch (cmd->verb) {
1295 case SCTP_CMD_NEW_ASOC:
1296 /* Register a new association. */
1298 sctp_outq_uncork(&asoc->outqueue, gfp);
1302 /* Register with the endpoint. */
1303 asoc = cmd->obj.asoc;
1304 BUG_ON(asoc->peer.primary_path == NULL);
1305 sctp_endpoint_add_asoc(ep, asoc);
1308 case SCTP_CMD_UPDATE_ASSOC:
1309 sctp_cmd_assoc_update(commands, asoc, cmd->obj.asoc);
1312 case SCTP_CMD_PURGE_OUTQUEUE:
1313 sctp_outq_teardown(&asoc->outqueue);
1316 case SCTP_CMD_DELETE_TCB:
1318 sctp_outq_uncork(&asoc->outqueue, gfp);
1321 /* Delete the current association. */
1322 sctp_cmd_delete_tcb(commands, asoc);
1326 case SCTP_CMD_NEW_STATE:
1327 /* Enter a new state. */
1328 sctp_cmd_new_state(commands, asoc, cmd->obj.state);
1331 case SCTP_CMD_REPORT_TSN:
1332 /* Record the arrival of a TSN. */
1333 error = sctp_tsnmap_mark(&asoc->peer.tsn_map,
1334 cmd->obj.u32, NULL);
1337 case SCTP_CMD_REPORT_FWDTSN:
1338 asoc->stream.si->report_ftsn(&asoc->ulpq, cmd->obj.u32);
1341 case SCTP_CMD_PROCESS_FWDTSN:
1342 asoc->stream.si->handle_ftsn(&asoc->ulpq,
1346 case SCTP_CMD_GEN_SACK:
1347 /* Generate a Selective ACK.
1348 * The argument tells us whether to just count
1349 * the packet and MAYBE generate a SACK, or
1352 force = cmd->obj.i32;
1353 error = sctp_gen_sack(asoc, force, commands);
1356 case SCTP_CMD_PROCESS_SACK:
1357 /* Process an inbound SACK. */
1358 error = sctp_cmd_process_sack(commands, asoc,
1362 case SCTP_CMD_GEN_INIT_ACK:
1363 /* Generate an INIT ACK chunk. */
1364 new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC,
1369 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1370 SCTP_CHUNK(new_obj));
1373 case SCTP_CMD_PEER_INIT:
1374 /* Process a unified INIT from the peer.
1375 * Note: Only used during INIT-ACK processing. If
1376 * there is an error just return to the outter
1377 * layer which will bail.
1379 error = sctp_cmd_process_init(commands, asoc, chunk,
1380 cmd->obj.init, gfp);
1383 case SCTP_CMD_GEN_COOKIE_ECHO:
1384 /* Generate a COOKIE ECHO chunk. */
1385 new_obj = sctp_make_cookie_echo(asoc, chunk);
1388 sctp_chunk_free(cmd->obj.chunk);
1391 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1392 SCTP_CHUNK(new_obj));
1394 /* If there is an ERROR chunk to be sent along with
1395 * the COOKIE_ECHO, send it, too.
1398 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1399 SCTP_CHUNK(cmd->obj.chunk));
1401 if (new_obj->transport) {
1402 new_obj->transport->init_sent_count++;
1403 asoc->init_last_sent_to = new_obj->transport;
1406 /* FIXME - Eventually come up with a cleaner way to
1407 * enabling COOKIE-ECHO + DATA bundling during
1408 * multihoming stale cookie scenarios, the following
1409 * command plays with asoc->peer.retran_path to
1410 * avoid the problem of sending the COOKIE-ECHO and
1411 * DATA in different paths, which could result
1412 * in the association being ABORTed if the DATA chunk
1413 * is processed first by the server. Checking the
1414 * init error counter simply causes this command
1415 * to be executed only during failed attempts of
1416 * association establishment.
1418 if ((asoc->peer.retran_path !=
1419 asoc->peer.primary_path) &&
1420 (asoc->init_err_counter > 0)) {
1421 sctp_add_cmd_sf(commands,
1422 SCTP_CMD_FORCE_PRIM_RETRAN,
1428 case SCTP_CMD_GEN_SHUTDOWN:
1429 /* Generate SHUTDOWN when in SHUTDOWN_SENT state.
1430 * Reset error counts.
1432 asoc->overall_error_count = 0;
1434 /* Generate a SHUTDOWN chunk. */
1435 new_obj = sctp_make_shutdown(asoc, chunk);
1438 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1439 SCTP_CHUNK(new_obj));
1442 case SCTP_CMD_CHUNK_ULP:
1443 /* Send a chunk to the sockets layer. */
1444 pr_debug("%s: sm_sideff: chunk_up:%p, ulpq:%p\n",
1445 __func__, cmd->obj.chunk, &asoc->ulpq);
1447 asoc->stream.si->ulpevent_data(&asoc->ulpq,
1452 case SCTP_CMD_EVENT_ULP:
1453 /* Send a notification to the sockets layer. */
1454 pr_debug("%s: sm_sideff: event_up:%p, ulpq:%p\n",
1455 __func__, cmd->obj.ulpevent, &asoc->ulpq);
1457 asoc->stream.si->enqueue_event(&asoc->ulpq,
1461 case SCTP_CMD_REPLY:
1462 /* If an caller has not already corked, do cork. */
1463 if (!asoc->outqueue.cork) {
1464 sctp_outq_cork(&asoc->outqueue);
1467 /* Send a chunk to our peer. */
1468 sctp_outq_tail(&asoc->outqueue, cmd->obj.chunk, gfp);
1471 case SCTP_CMD_SEND_PKT:
1472 /* Send a full packet to our peer. */
1473 packet = cmd->obj.packet;
1474 sctp_packet_transmit(packet, gfp);
1475 sctp_ootb_pkt_free(packet);
1478 case SCTP_CMD_T1_RETRAN:
1479 /* Mark a transport for retransmission. */
1480 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1484 case SCTP_CMD_RETRAN:
1485 /* Mark a transport for retransmission. */
1486 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1490 case SCTP_CMD_ECN_CE:
1491 /* Do delayed CE processing. */
1492 sctp_do_ecn_ce_work(asoc, cmd->obj.u32);
1495 case SCTP_CMD_ECN_ECNE:
1496 /* Do delayed ECNE processing. */
1497 new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32,
1500 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1501 SCTP_CHUNK(new_obj));
1504 case SCTP_CMD_ECN_CWR:
1505 /* Do delayed CWR processing. */
1506 sctp_do_ecn_cwr_work(asoc, cmd->obj.u32);
1509 case SCTP_CMD_SETUP_T2:
1510 sctp_cmd_setup_t2(commands, asoc, cmd->obj.chunk);
1513 case SCTP_CMD_TIMER_START_ONCE:
1514 timer = &asoc->timers[cmd->obj.to];
1516 if (timer_pending(timer))
1520 case SCTP_CMD_TIMER_START:
1521 timer = &asoc->timers[cmd->obj.to];
1522 timeout = asoc->timeouts[cmd->obj.to];
1525 timer->expires = jiffies + timeout;
1526 sctp_association_hold(asoc);
1530 case SCTP_CMD_TIMER_RESTART:
1531 timer = &asoc->timers[cmd->obj.to];
1532 timeout = asoc->timeouts[cmd->obj.to];
1533 if (!mod_timer(timer, jiffies + timeout))
1534 sctp_association_hold(asoc);
1537 case SCTP_CMD_TIMER_STOP:
1538 timer = &asoc->timers[cmd->obj.to];
1539 if (del_timer(timer))
1540 sctp_association_put(asoc);
1543 case SCTP_CMD_INIT_CHOOSE_TRANSPORT:
1544 chunk = cmd->obj.chunk;
1545 t = sctp_assoc_choose_alter_transport(asoc,
1546 asoc->init_last_sent_to);
1547 asoc->init_last_sent_to = t;
1548 chunk->transport = t;
1549 t->init_sent_count++;
1550 /* Set the new transport as primary */
1551 sctp_assoc_set_primary(asoc, t);
1554 case SCTP_CMD_INIT_RESTART:
1555 /* Do the needed accounting and updates
1556 * associated with restarting an initialization
1557 * timer. Only multiply the timeout by two if
1558 * all transports have been tried at the current
1561 sctp_cmd_t1_timer_update(asoc,
1562 SCTP_EVENT_TIMEOUT_T1_INIT,
1565 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
1566 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
1569 case SCTP_CMD_COOKIEECHO_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
1576 sctp_cmd_t1_timer_update(asoc,
1577 SCTP_EVENT_TIMEOUT_T1_COOKIE,
1580 /* If we've sent any data bundled with
1581 * COOKIE-ECHO we need to resend.
1583 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1585 sctp_retransmit_mark(&asoc->outqueue, t,
1589 sctp_add_cmd_sf(commands,
1590 SCTP_CMD_TIMER_RESTART,
1591 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
1594 case SCTP_CMD_INIT_FAILED:
1595 sctp_cmd_init_failed(commands, asoc, cmd->obj.u32);
1598 case SCTP_CMD_ASSOC_FAILED:
1599 sctp_cmd_assoc_failed(commands, asoc, event_type,
1600 subtype, chunk, cmd->obj.u32);
1603 case SCTP_CMD_INIT_COUNTER_INC:
1604 asoc->init_err_counter++;
1607 case SCTP_CMD_INIT_COUNTER_RESET:
1608 asoc->init_err_counter = 0;
1609 asoc->init_cycle = 0;
1610 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1612 t->init_sent_count = 0;
1616 case SCTP_CMD_REPORT_DUP:
1617 sctp_tsnmap_mark_dup(&asoc->peer.tsn_map,
1621 case SCTP_CMD_REPORT_BAD_TAG:
1622 pr_debug("%s: vtag mismatch!\n", __func__);
1625 case SCTP_CMD_STRIKE:
1626 /* Mark one strike against a transport. */
1627 sctp_do_8_2_transport_strike(commands, asoc,
1628 cmd->obj.transport, 0);
1631 case SCTP_CMD_TRANSPORT_IDLE:
1632 t = cmd->obj.transport;
1633 sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE);
1636 case SCTP_CMD_TRANSPORT_HB_SENT:
1637 t = cmd->obj.transport;
1638 sctp_do_8_2_transport_strike(commands, asoc,
1643 case SCTP_CMD_TRANSPORT_ON:
1644 t = cmd->obj.transport;
1645 sctp_cmd_transport_on(commands, asoc, t, chunk);
1648 case SCTP_CMD_HB_TIMERS_START:
1649 sctp_cmd_hb_timers_start(commands, asoc);
1652 case SCTP_CMD_HB_TIMER_UPDATE:
1653 t = cmd->obj.transport;
1654 sctp_transport_reset_hb_timer(t);
1657 case SCTP_CMD_HB_TIMERS_STOP:
1658 sctp_cmd_hb_timers_stop(commands, asoc);
1661 case SCTP_CMD_REPORT_ERROR:
1662 error = cmd->obj.error;
1665 case SCTP_CMD_PROCESS_CTSN:
1666 /* Dummy up a SACK for processing. */
1667 sackh.cum_tsn_ack = cmd->obj.be32;
1668 sackh.a_rwnd = htonl(asoc->peer.rwnd +
1669 asoc->outqueue.outstanding_bytes);
1670 sackh.num_gap_ack_blocks = 0;
1671 sackh.num_dup_tsns = 0;
1672 chunk->subh.sack_hdr = &sackh;
1673 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK,
1677 case SCTP_CMD_DISCARD_PACKET:
1678 /* We need to discard the whole packet.
1679 * Uncork the queue since there might be
1682 chunk->pdiscard = 1;
1684 sctp_outq_uncork(&asoc->outqueue, gfp);
1689 case SCTP_CMD_RTO_PENDING:
1690 t = cmd->obj.transport;
1694 case SCTP_CMD_PART_DELIVER:
1695 asoc->stream.si->start_pd(&asoc->ulpq, GFP_ATOMIC);
1698 case SCTP_CMD_RENEGE:
1699 asoc->stream.si->renege_events(&asoc->ulpq,
1704 case SCTP_CMD_SETUP_T4:
1705 sctp_cmd_setup_t4(commands, asoc, cmd->obj.chunk);
1708 case SCTP_CMD_PROCESS_OPERR:
1709 sctp_cmd_process_operr(commands, asoc, chunk);
1711 case SCTP_CMD_CLEAR_INIT_TAG:
1712 asoc->peer.i.init_tag = 0;
1714 case SCTP_CMD_DEL_NON_PRIMARY:
1715 sctp_cmd_del_non_primary(asoc);
1717 case SCTP_CMD_T3_RTX_TIMERS_STOP:
1718 sctp_cmd_t3_rtx_timers_stop(commands, asoc);
1720 case SCTP_CMD_FORCE_PRIM_RETRAN:
1721 t = asoc->peer.retran_path;
1722 asoc->peer.retran_path = asoc->peer.primary_path;
1723 sctp_outq_uncork(&asoc->outqueue, gfp);
1725 asoc->peer.retran_path = t;
1727 case SCTP_CMD_SET_SK_ERR:
1728 sctp_cmd_set_sk_err(asoc, cmd->obj.error);
1730 case SCTP_CMD_ASSOC_CHANGE:
1731 sctp_cmd_assoc_change(commands, asoc,
1734 case SCTP_CMD_ADAPTATION_IND:
1735 sctp_cmd_adaptation_ind(commands, asoc);
1737 case SCTP_CMD_PEER_NO_AUTH:
1738 sctp_cmd_peer_no_auth(commands, asoc);
1741 case SCTP_CMD_ASSOC_SHKEY:
1742 error = sctp_auth_asoc_init_active_key(asoc,
1745 case SCTP_CMD_UPDATE_INITTAG:
1746 asoc->peer.i.init_tag = cmd->obj.u32;
1748 case SCTP_CMD_SEND_MSG:
1749 if (!asoc->outqueue.cork) {
1750 sctp_outq_cork(&asoc->outqueue);
1753 sctp_cmd_send_msg(asoc, cmd->obj.msg, gfp);
1755 case SCTP_CMD_PURGE_ASCONF_QUEUE:
1756 sctp_asconf_queue_teardown(asoc);
1759 case SCTP_CMD_SET_ASOC:
1760 if (asoc && local_cork) {
1761 sctp_outq_uncork(&asoc->outqueue, gfp);
1764 asoc = cmd->obj.asoc;
1768 pr_warn("Impossible command: %u\n",
1778 /* If this is in response to a received chunk, wait until
1779 * we are done with the packet to open the queue so that we don't
1780 * send multiple packets in response to a single request.
1782 if (asoc && SCTP_EVENT_T_CHUNK == event_type && chunk) {
1783 if (chunk->end_of_packet || chunk->singleton)
1784 sctp_outq_uncork(&asoc->outqueue, gfp);
1785 } else if (local_cork)
1786 sctp_outq_uncork(&asoc->outqueue, gfp);
1788 if (sp->data_ready_signalled)
1789 sp->data_ready_signalled = 0;