1 /* SCTP kernel implementation
2 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999-2000 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 * Copyright (c) 2001 Intel Corp.
6 * Copyright (c) 2001 La Monte H.P. Yarroll
8 * This file is part of the SCTP kernel implementation
10 * This module provides the abstraction for an SCTP association.
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)
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.
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.
29 * Please send any bug reports or fixes you make to the
31 * lksctp developers <lksctp-developers@lists.sourceforge.net>
33 * Or submit a bug report through the following website:
34 * http://www.sf.net/projects/lksctp
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@us.ibm.com>
40 * Xingang Guo <xingang.guo@intel.com>
41 * Hui Huang <hui.huang@nokia.com>
42 * Sridhar Samudrala <sri@us.ibm.com>
43 * Daisy Chang <daisyc@us.ibm.com>
44 * Ryan Layer <rmlayer@us.ibm.com>
45 * Kevin Gao <kevin.gao@intel.com>
47 * Any bugs reported given to us we will try to fix... any fixes shared will
48 * be incorporated into the next SCTP release.
51 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
53 #include <linux/types.h>
54 #include <linux/fcntl.h>
55 #include <linux/poll.h>
56 #include <linux/init.h>
58 #include <linux/slab.h>
61 #include <net/sctp/sctp.h>
62 #include <net/sctp/sm.h>
64 /* Forward declarations for internal functions. */
65 static void sctp_assoc_bh_rcv(struct work_struct *work);
66 static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc);
67 static void sctp_assoc_free_asconf_queue(struct sctp_association *asoc);
69 /* 1st Level Abstractions. */
71 /* Initialize a new association from provided memory. */
72 static struct sctp_association *sctp_association_init(struct sctp_association *asoc,
73 const struct sctp_endpoint *ep,
74 const struct sock *sk,
78 struct net *net = sock_net(sk);
84 /* Retrieve the SCTP per socket area. */
85 sp = sctp_sk((struct sock *)sk);
87 /* Discarding const is appropriate here. */
88 asoc->ep = (struct sctp_endpoint *)ep;
89 sctp_endpoint_hold(asoc->ep);
92 asoc->base.sk = (struct sock *)sk;
93 sock_hold(asoc->base.sk);
95 /* Initialize the common base substructure. */
96 asoc->base.type = SCTP_EP_TYPE_ASSOCIATION;
98 /* Initialize the object handling fields. */
99 atomic_set(&asoc->base.refcnt, 1);
101 asoc->base.malloced = 0;
103 /* Initialize the bind addr area. */
104 sctp_bind_addr_init(&asoc->base.bind_addr, ep->base.bind_addr.port);
106 asoc->state = SCTP_STATE_CLOSED;
108 /* Set these values from the socket values, a conversion between
109 * millsecons to seconds/microseconds must also be done.
111 asoc->cookie_life.tv_sec = sp->assocparams.sasoc_cookie_life / 1000;
112 asoc->cookie_life.tv_usec = (sp->assocparams.sasoc_cookie_life % 1000)
114 asoc->frag_point = 0;
115 asoc->user_frag = sp->user_frag;
117 /* Set the association max_retrans and RTO values from the
120 asoc->max_retrans = sp->assocparams.sasoc_asocmaxrxt;
121 asoc->pf_retrans = net->sctp.pf_retrans;
123 asoc->rto_initial = msecs_to_jiffies(sp->rtoinfo.srto_initial);
124 asoc->rto_max = msecs_to_jiffies(sp->rtoinfo.srto_max);
125 asoc->rto_min = msecs_to_jiffies(sp->rtoinfo.srto_min);
127 asoc->overall_error_count = 0;
129 /* Initialize the association's heartbeat interval based on the
130 * sock configured value.
132 asoc->hbinterval = msecs_to_jiffies(sp->hbinterval);
134 /* Initialize path max retrans value. */
135 asoc->pathmaxrxt = sp->pathmaxrxt;
137 /* Initialize default path MTU. */
138 asoc->pathmtu = sp->pathmtu;
140 /* Set association default SACK delay */
141 asoc->sackdelay = msecs_to_jiffies(sp->sackdelay);
142 asoc->sackfreq = sp->sackfreq;
144 /* Set the association default flags controlling
145 * Heartbeat, SACK delay, and Path MTU Discovery.
147 asoc->param_flags = sp->param_flags;
149 /* Initialize the maximum mumber of new data packets that can be sent
152 asoc->max_burst = sp->max_burst;
154 /* initialize association timers */
155 asoc->timeouts[SCTP_EVENT_TIMEOUT_NONE] = 0;
156 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = asoc->rto_initial;
157 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = asoc->rto_initial;
158 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = asoc->rto_initial;
159 asoc->timeouts[SCTP_EVENT_TIMEOUT_T3_RTX] = 0;
160 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = 0;
162 /* sctpimpguide Section 2.12.2
163 * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the
164 * recommended value of 5 times 'RTO.Max'.
166 asoc->timeouts[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD]
169 asoc->timeouts[SCTP_EVENT_TIMEOUT_HEARTBEAT] = 0;
170 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = asoc->sackdelay;
171 asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] =
172 min_t(unsigned long, sp->autoclose, net->sctp.max_autoclose) * HZ;
174 /* Initializes the timers */
175 for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i)
176 setup_timer(&asoc->timers[i], sctp_timer_events[i],
177 (unsigned long)asoc);
179 /* Pull default initialization values from the sock options.
180 * Note: This assumes that the values have already been
181 * validated in the sock.
183 asoc->c.sinit_max_instreams = sp->initmsg.sinit_max_instreams;
184 asoc->c.sinit_num_ostreams = sp->initmsg.sinit_num_ostreams;
185 asoc->max_init_attempts = sp->initmsg.sinit_max_attempts;
187 asoc->max_init_timeo =
188 msecs_to_jiffies(sp->initmsg.sinit_max_init_timeo);
190 /* Allocate storage for the ssnmap after the inbound and outbound
191 * streams have been negotiated during Init.
195 /* Set the local window size for receive.
196 * This is also the rcvbuf space per association.
197 * RFC 6 - A SCTP receiver MUST be able to receive a minimum of
198 * 1500 bytes in one SCTP packet.
200 if ((sk->sk_rcvbuf/2) < SCTP_DEFAULT_MINWINDOW)
201 asoc->rwnd = SCTP_DEFAULT_MINWINDOW;
203 asoc->rwnd = sk->sk_rcvbuf/2;
205 asoc->a_rwnd = asoc->rwnd;
208 asoc->rwnd_press = 0;
210 /* Use my own max window until I learn something better. */
211 asoc->peer.rwnd = SCTP_DEFAULT_MAXWINDOW;
213 /* Set the sndbuf size for transmit. */
214 asoc->sndbuf_used = 0;
216 /* Initialize the receive memory counter */
217 atomic_set(&asoc->rmem_alloc, 0);
219 init_waitqueue_head(&asoc->wait);
221 asoc->c.my_vtag = sctp_generate_tag(ep);
222 asoc->peer.i.init_tag = 0; /* INIT needs a vtag of 0. */
223 asoc->c.peer_vtag = 0;
225 asoc->c.peer_ttag = 0;
226 asoc->c.my_port = ep->base.bind_addr.port;
228 asoc->c.initial_tsn = sctp_generate_tsn(ep);
230 asoc->next_tsn = asoc->c.initial_tsn;
232 asoc->ctsn_ack_point = asoc->next_tsn - 1;
233 asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
234 asoc->highest_sacked = asoc->ctsn_ack_point;
235 asoc->last_cwr_tsn = asoc->ctsn_ack_point;
236 asoc->unack_data = 0;
238 /* ADDIP Section 4.1 Asconf Chunk Procedures
240 * When an endpoint has an ASCONF signaled change to be sent to the
241 * remote endpoint it should do the following:
243 * A2) a serial number should be assigned to the chunk. The serial
244 * number SHOULD be a monotonically increasing number. The serial
245 * numbers SHOULD be initialized at the start of the
246 * association to the same value as the initial TSN.
248 asoc->addip_serial = asoc->c.initial_tsn;
250 INIT_LIST_HEAD(&asoc->addip_chunk_list);
251 INIT_LIST_HEAD(&asoc->asconf_ack_list);
253 /* Make an empty list of remote transport addresses. */
254 INIT_LIST_HEAD(&asoc->peer.transport_addr_list);
255 asoc->peer.transport_count = 0;
257 /* RFC 2960 5.1 Normal Establishment of an Association
259 * After the reception of the first data chunk in an
260 * association the endpoint must immediately respond with a
261 * sack to acknowledge the data chunk. Subsequent
262 * acknowledgements should be done as described in Section
265 * [We implement this by telling a new association that it
266 * already received one packet.]
268 asoc->peer.sack_needed = 1;
269 asoc->peer.sack_cnt = 0;
270 asoc->peer.sack_generation = 1;
272 /* Assume that the peer will tell us if he recognizes ASCONF
273 * as part of INIT exchange.
274 * The sctp_addip_noauth option is there for backward compatibilty
275 * and will revert old behavior.
277 asoc->peer.asconf_capable = 0;
278 if (net->sctp.addip_noauth)
279 asoc->peer.asconf_capable = 1;
280 asoc->asconf_addr_del_pending = NULL;
281 asoc->src_out_of_asoc_ok = 0;
282 asoc->new_transport = NULL;
284 /* Create an input queue. */
285 sctp_inq_init(&asoc->base.inqueue);
286 sctp_inq_set_th_handler(&asoc->base.inqueue, sctp_assoc_bh_rcv);
288 /* Create an output queue. */
289 sctp_outq_init(asoc, &asoc->outqueue);
291 if (!sctp_ulpq_init(&asoc->ulpq, asoc))
294 memset(&asoc->peer.tsn_map, 0, sizeof(struct sctp_tsnmap));
300 /* Assume that peer would support both address types unless we are
303 asoc->peer.ipv4_address = 1;
304 if (asoc->base.sk->sk_family == PF_INET6)
305 asoc->peer.ipv6_address = 1;
306 INIT_LIST_HEAD(&asoc->asocs);
308 asoc->autoclose = sp->autoclose;
310 asoc->default_stream = sp->default_stream;
311 asoc->default_ppid = sp->default_ppid;
312 asoc->default_flags = sp->default_flags;
313 asoc->default_context = sp->default_context;
314 asoc->default_timetolive = sp->default_timetolive;
315 asoc->default_rcv_context = sp->default_rcv_context;
317 /* SCTP_GET_ASSOC_STATS COUNTERS */
318 memset(&asoc->stats, 0, sizeof(struct sctp_priv_assoc_stats));
320 /* AUTH related initializations */
321 INIT_LIST_HEAD(&asoc->endpoint_shared_keys);
322 err = sctp_auth_asoc_copy_shkeys(ep, asoc, gfp);
326 asoc->active_key_id = ep->active_key_id;
327 asoc->asoc_shared_key = NULL;
329 asoc->default_hmac_id = 0;
330 /* Save the hmacs and chunks list into this association */
331 if (ep->auth_hmacs_list)
332 memcpy(asoc->c.auth_hmacs, ep->auth_hmacs_list,
333 ntohs(ep->auth_hmacs_list->param_hdr.length));
334 if (ep->auth_chunk_list)
335 memcpy(asoc->c.auth_chunks, ep->auth_chunk_list,
336 ntohs(ep->auth_chunk_list->param_hdr.length));
338 /* Get the AUTH random number for this association */
339 p = (sctp_paramhdr_t *)asoc->c.auth_random;
340 p->type = SCTP_PARAM_RANDOM;
341 p->length = htons(sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH);
342 get_random_bytes(p+1, SCTP_AUTH_RANDOM_LENGTH);
347 sctp_endpoint_put(asoc->ep);
348 sock_put(asoc->base.sk);
352 /* Allocate and initialize a new association */
353 struct sctp_association *sctp_association_new(const struct sctp_endpoint *ep,
354 const struct sock *sk,
358 struct sctp_association *asoc;
360 asoc = t_new(struct sctp_association, gfp);
364 if (!sctp_association_init(asoc, ep, sk, scope, gfp))
367 asoc->base.malloced = 1;
368 SCTP_DBG_OBJCNT_INC(assoc);
369 SCTP_DEBUG_PRINTK("Created asoc %p\n", asoc);
379 /* Free this association if possible. There may still be users, so
380 * the actual deallocation may be delayed.
382 void sctp_association_free(struct sctp_association *asoc)
384 struct sock *sk = asoc->base.sk;
385 struct sctp_transport *transport;
386 struct list_head *pos, *temp;
389 /* Only real associations count against the endpoint, so
390 * don't bother for if this is a temporary association.
393 list_del(&asoc->asocs);
395 /* Decrement the backlog value for a TCP-style listening
398 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
399 sk->sk_ack_backlog--;
402 /* Mark as dead, so other users can know this structure is
407 /* Dispose of any data lying around in the outqueue. */
408 sctp_outq_free(&asoc->outqueue);
410 /* Dispose of any pending messages for the upper layer. */
411 sctp_ulpq_free(&asoc->ulpq);
413 /* Dispose of any pending chunks on the inqueue. */
414 sctp_inq_free(&asoc->base.inqueue);
416 sctp_tsnmap_free(&asoc->peer.tsn_map);
418 /* Free ssnmap storage. */
419 sctp_ssnmap_free(asoc->ssnmap);
421 /* Clean up the bound address list. */
422 sctp_bind_addr_free(&asoc->base.bind_addr);
424 /* Do we need to go through all of our timers and
425 * delete them? To be safe we will try to delete all, but we
426 * should be able to go through and make a guess based
429 for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) {
430 if (del_timer(&asoc->timers[i]))
431 sctp_association_put(asoc);
434 /* Free peer's cached cookie. */
435 kfree(asoc->peer.cookie);
436 kfree(asoc->peer.peer_random);
437 kfree(asoc->peer.peer_chunks);
438 kfree(asoc->peer.peer_hmacs);
440 /* Release the transport structures. */
441 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
442 transport = list_entry(pos, struct sctp_transport, transports);
444 sctp_transport_free(transport);
447 asoc->peer.transport_count = 0;
449 sctp_asconf_queue_teardown(asoc);
451 /* Free pending address space being deleted */
452 if (asoc->asconf_addr_del_pending != NULL)
453 kfree(asoc->asconf_addr_del_pending);
455 /* AUTH - Free the endpoint shared keys */
456 sctp_auth_destroy_keys(&asoc->endpoint_shared_keys);
458 /* AUTH - Free the association shared key */
459 sctp_auth_key_put(asoc->asoc_shared_key);
461 sctp_association_put(asoc);
464 /* Cleanup and free up an association. */
465 static void sctp_association_destroy(struct sctp_association *asoc)
467 SCTP_ASSERT(asoc->base.dead, "Assoc is not dead", return);
469 sctp_endpoint_put(asoc->ep);
470 sock_put(asoc->base.sk);
472 if (asoc->assoc_id != 0) {
473 spin_lock_bh(&sctp_assocs_id_lock);
474 idr_remove(&sctp_assocs_id, asoc->assoc_id);
475 spin_unlock_bh(&sctp_assocs_id_lock);
478 WARN_ON(atomic_read(&asoc->rmem_alloc));
480 if (asoc->base.malloced) {
482 SCTP_DBG_OBJCNT_DEC(assoc);
486 /* Change the primary destination address for the peer. */
487 void sctp_assoc_set_primary(struct sctp_association *asoc,
488 struct sctp_transport *transport)
492 /* it's a changeover only if we already have a primary path
493 * that we are changing
495 if (asoc->peer.primary_path != NULL &&
496 asoc->peer.primary_path != transport)
499 asoc->peer.primary_path = transport;
501 /* Set a default msg_name for events. */
502 memcpy(&asoc->peer.primary_addr, &transport->ipaddr,
503 sizeof(union sctp_addr));
505 /* If the primary path is changing, assume that the
506 * user wants to use this new path.
508 if ((transport->state == SCTP_ACTIVE) ||
509 (transport->state == SCTP_UNKNOWN))
510 asoc->peer.active_path = transport;
513 * SFR-CACC algorithm:
514 * Upon the receipt of a request to change the primary
515 * destination address, on the data structure for the new
516 * primary destination, the sender MUST do the following:
518 * 1) If CHANGEOVER_ACTIVE is set, then there was a switch
519 * to this destination address earlier. The sender MUST set
520 * CYCLING_CHANGEOVER to indicate that this switch is a
521 * double switch to the same destination address.
523 * Really, only bother is we have data queued or outstanding on
526 if (!asoc->outqueue.outstanding_bytes && !asoc->outqueue.out_qlen)
529 if (transport->cacc.changeover_active)
530 transport->cacc.cycling_changeover = changeover;
532 /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that
533 * a changeover has occurred.
535 transport->cacc.changeover_active = changeover;
537 /* 3) The sender MUST store the next TSN to be sent in
538 * next_tsn_at_change.
540 transport->cacc.next_tsn_at_change = asoc->next_tsn;
543 /* Remove a transport from an association. */
544 void sctp_assoc_rm_peer(struct sctp_association *asoc,
545 struct sctp_transport *peer)
547 struct list_head *pos;
548 struct sctp_transport *transport;
550 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_rm_peer:association %p addr: ",
554 ntohs(peer->ipaddr.v4.sin_port));
556 /* If we are to remove the current retran_path, update it
557 * to the next peer before removing this peer from the list.
559 if (asoc->peer.retran_path == peer)
560 sctp_assoc_update_retran_path(asoc);
562 /* Remove this peer from the list. */
563 list_del_rcu(&peer->transports);
565 /* Get the first transport of asoc. */
566 pos = asoc->peer.transport_addr_list.next;
567 transport = list_entry(pos, struct sctp_transport, transports);
569 /* Update any entries that match the peer to be deleted. */
570 if (asoc->peer.primary_path == peer)
571 sctp_assoc_set_primary(asoc, transport);
572 if (asoc->peer.active_path == peer)
573 asoc->peer.active_path = transport;
574 if (asoc->peer.retran_path == peer)
575 asoc->peer.retran_path = transport;
576 if (asoc->peer.last_data_from == peer)
577 asoc->peer.last_data_from = transport;
579 /* If we remove the transport an INIT was last sent to, set it to
580 * NULL. Combined with the update of the retran path above, this
581 * will cause the next INIT to be sent to the next available
582 * transport, maintaining the cycle.
584 if (asoc->init_last_sent_to == peer)
585 asoc->init_last_sent_to = NULL;
587 /* If we remove the transport an SHUTDOWN was last sent to, set it
588 * to NULL. Combined with the update of the retran path above, this
589 * will cause the next SHUTDOWN to be sent to the next available
590 * transport, maintaining the cycle.
592 if (asoc->shutdown_last_sent_to == peer)
593 asoc->shutdown_last_sent_to = NULL;
595 /* If we remove the transport an ASCONF was last sent to, set it to
598 if (asoc->addip_last_asconf &&
599 asoc->addip_last_asconf->transport == peer)
600 asoc->addip_last_asconf->transport = NULL;
602 /* If we have something on the transmitted list, we have to
603 * save it off. The best place is the active path.
605 if (!list_empty(&peer->transmitted)) {
606 struct sctp_transport *active = asoc->peer.active_path;
607 struct sctp_chunk *ch;
609 /* Reset the transport of each chunk on this list */
610 list_for_each_entry(ch, &peer->transmitted,
612 ch->transport = NULL;
613 ch->rtt_in_progress = 0;
616 list_splice_tail_init(&peer->transmitted,
617 &active->transmitted);
619 /* Start a T3 timer here in case it wasn't running so
620 * that these migrated packets have a chance to get
623 if (!timer_pending(&active->T3_rtx_timer))
624 if (!mod_timer(&active->T3_rtx_timer,
625 jiffies + active->rto))
626 sctp_transport_hold(active);
629 asoc->peer.transport_count--;
631 sctp_transport_free(peer);
634 /* Add a transport address to an association. */
635 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc,
636 const union sctp_addr *addr,
638 const int peer_state)
640 struct net *net = sock_net(asoc->base.sk);
641 struct sctp_transport *peer;
642 struct sctp_sock *sp;
645 sp = sctp_sk(asoc->base.sk);
647 /* AF_INET and AF_INET6 share common port field. */
648 port = ntohs(addr->v4.sin_port);
650 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_add_peer:association %p addr: ",
651 " port: %d state:%d\n",
657 /* Set the port if it has not been set yet. */
658 if (0 == asoc->peer.port)
659 asoc->peer.port = port;
661 /* Check to see if this is a duplicate. */
662 peer = sctp_assoc_lookup_paddr(asoc, addr);
664 /* An UNKNOWN state is only set on transports added by
665 * user in sctp_connectx() call. Such transports should be
666 * considered CONFIRMED per RFC 4960, Section 5.4.
668 if (peer->state == SCTP_UNKNOWN) {
669 peer->state = SCTP_ACTIVE;
674 peer = sctp_transport_new(net, addr, gfp);
678 sctp_transport_set_owner(peer, asoc);
680 /* Initialize the peer's heartbeat interval based on the
681 * association configured value.
683 peer->hbinterval = asoc->hbinterval;
685 /* Set the path max_retrans. */
686 peer->pathmaxrxt = asoc->pathmaxrxt;
688 /* And the partial failure retrnas threshold */
689 peer->pf_retrans = asoc->pf_retrans;
691 /* Initialize the peer's SACK delay timeout based on the
692 * association configured value.
694 peer->sackdelay = asoc->sackdelay;
695 peer->sackfreq = asoc->sackfreq;
697 /* Enable/disable heartbeat, SACK delay, and path MTU discovery
698 * based on association setting.
700 peer->param_flags = asoc->param_flags;
702 sctp_transport_route(peer, NULL, sp);
704 /* Initialize the pmtu of the transport. */
705 if (peer->param_flags & SPP_PMTUD_DISABLE) {
707 peer->pathmtu = asoc->pathmtu;
709 peer->pathmtu = SCTP_DEFAULT_MAXSEGMENT;
712 /* If this is the first transport addr on this association,
713 * initialize the association PMTU to the peer's PMTU.
714 * If not and the current association PMTU is higher than the new
715 * peer's PMTU, reset the association PMTU to the new peer's PMTU.
718 asoc->pathmtu = min_t(int, peer->pathmtu, asoc->pathmtu);
720 asoc->pathmtu = peer->pathmtu;
722 SCTP_DEBUG_PRINTK("sctp_assoc_add_peer:association %p PMTU set to "
723 "%d\n", asoc, asoc->pathmtu);
724 peer->pmtu_pending = 0;
726 asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
728 /* The asoc->peer.port might not be meaningful yet, but
729 * initialize the packet structure anyway.
731 sctp_packet_init(&peer->packet, peer, asoc->base.bind_addr.port,
736 * o The initial cwnd before DATA transmission or after a sufficiently
737 * long idle period MUST be set to
738 * min(4*MTU, max(2*MTU, 4380 bytes))
740 * o The initial value of ssthresh MAY be arbitrarily high
741 * (for example, implementations MAY use the size of the
742 * receiver advertised window).
744 peer->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380));
746 /* At this point, we may not have the receiver's advertised window,
747 * so initialize ssthresh to the default value and it will be set
748 * later when we process the INIT.
750 peer->ssthresh = SCTP_DEFAULT_MAXWINDOW;
752 peer->partial_bytes_acked = 0;
753 peer->flight_size = 0;
754 peer->burst_limited = 0;
756 /* Set the transport's RTO.initial value */
757 peer->rto = asoc->rto_initial;
758 sctp_max_rto(asoc, peer);
760 /* Set the peer's active state. */
761 peer->state = peer_state;
763 /* Attach the remote transport to our asoc. */
764 list_add_tail_rcu(&peer->transports, &asoc->peer.transport_addr_list);
765 asoc->peer.transport_count++;
767 /* If we do not yet have a primary path, set one. */
768 if (!asoc->peer.primary_path) {
769 sctp_assoc_set_primary(asoc, peer);
770 asoc->peer.retran_path = peer;
773 if (asoc->peer.active_path == asoc->peer.retran_path &&
774 peer->state != SCTP_UNCONFIRMED) {
775 asoc->peer.retran_path = peer;
781 /* Delete a transport address from an association. */
782 void sctp_assoc_del_peer(struct sctp_association *asoc,
783 const union sctp_addr *addr)
785 struct list_head *pos;
786 struct list_head *temp;
787 struct sctp_transport *transport;
789 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
790 transport = list_entry(pos, struct sctp_transport, transports);
791 if (sctp_cmp_addr_exact(addr, &transport->ipaddr)) {
792 /* Do book keeping for removing the peer and free it. */
793 sctp_assoc_rm_peer(asoc, transport);
799 /* Lookup a transport by address. */
800 struct sctp_transport *sctp_assoc_lookup_paddr(
801 const struct sctp_association *asoc,
802 const union sctp_addr *address)
804 struct sctp_transport *t;
806 /* Cycle through all transports searching for a peer address. */
808 list_for_each_entry(t, &asoc->peer.transport_addr_list,
810 if (sctp_cmp_addr_exact(address, &t->ipaddr))
817 /* Remove all transports except a give one */
818 void sctp_assoc_del_nonprimary_peers(struct sctp_association *asoc,
819 struct sctp_transport *primary)
821 struct sctp_transport *temp;
822 struct sctp_transport *t;
824 list_for_each_entry_safe(t, temp, &asoc->peer.transport_addr_list,
826 /* if the current transport is not the primary one, delete it */
828 sctp_assoc_rm_peer(asoc, t);
832 /* Engage in transport control operations.
833 * Mark the transport up or down and send a notification to the user.
834 * Select and update the new active and retran paths.
836 void sctp_assoc_control_transport(struct sctp_association *asoc,
837 struct sctp_transport *transport,
838 sctp_transport_cmd_t command,
839 sctp_sn_error_t error)
841 struct sctp_transport *t = NULL;
842 struct sctp_transport *first;
843 struct sctp_transport *second;
844 struct sctp_ulpevent *event;
845 struct sockaddr_storage addr;
847 bool ulp_notify = true;
849 /* Record the transition on the transport. */
851 case SCTP_TRANSPORT_UP:
852 /* If we are moving from UNCONFIRMED state due
853 * to heartbeat success, report the SCTP_ADDR_CONFIRMED
854 * state to the user, otherwise report SCTP_ADDR_AVAILABLE.
856 if (SCTP_UNCONFIRMED == transport->state &&
857 SCTP_HEARTBEAT_SUCCESS == error)
858 spc_state = SCTP_ADDR_CONFIRMED;
860 spc_state = SCTP_ADDR_AVAILABLE;
861 /* Don't inform ULP about transition from PF to
862 * active state and set cwnd to 1, see SCTP
863 * Quick failover draft section 5.1, point 5
865 if (transport->state == SCTP_PF) {
869 transport->state = SCTP_ACTIVE;
872 case SCTP_TRANSPORT_DOWN:
873 /* If the transport was never confirmed, do not transition it
874 * to inactive state. Also, release the cached route since
875 * there may be a better route next time.
877 if (transport->state != SCTP_UNCONFIRMED)
878 transport->state = SCTP_INACTIVE;
880 dst_release(transport->dst);
881 transport->dst = NULL;
884 spc_state = SCTP_ADDR_UNREACHABLE;
887 case SCTP_TRANSPORT_PF:
888 transport->state = SCTP_PF;
896 /* Generate and send a SCTP_PEER_ADDR_CHANGE notification to the
900 memset(&addr, 0, sizeof(struct sockaddr_storage));
901 memcpy(&addr, &transport->ipaddr,
902 transport->af_specific->sockaddr_len);
903 event = sctp_ulpevent_make_peer_addr_change(asoc, &addr,
904 0, spc_state, error, GFP_ATOMIC);
906 sctp_ulpq_tail_event(&asoc->ulpq, event);
909 /* Select new active and retran paths. */
911 /* Look for the two most recently used active transports.
913 * This code produces the wrong ordering whenever jiffies
914 * rolls over, but we still get usable transports, so we don't
917 first = NULL; second = NULL;
919 list_for_each_entry(t, &asoc->peer.transport_addr_list,
922 if ((t->state == SCTP_INACTIVE) ||
923 (t->state == SCTP_UNCONFIRMED) ||
924 (t->state == SCTP_PF))
926 if (!first || t->last_time_heard > first->last_time_heard) {
930 if (!second || t->last_time_heard > second->last_time_heard)
934 /* RFC 2960 6.4 Multi-Homed SCTP Endpoints
936 * By default, an endpoint should always transmit to the
937 * primary path, unless the SCTP user explicitly specifies the
938 * destination transport address (and possibly source
939 * transport address) to use.
941 * [If the primary is active but not most recent, bump the most
942 * recently used transport.]
944 if (((asoc->peer.primary_path->state == SCTP_ACTIVE) ||
945 (asoc->peer.primary_path->state == SCTP_UNKNOWN)) &&
946 first != asoc->peer.primary_path) {
948 first = asoc->peer.primary_path;
951 /* If we failed to find a usable transport, just camp on the
952 * primary, even if it is inactive.
955 first = asoc->peer.primary_path;
956 second = asoc->peer.primary_path;
959 /* Set the active and retran transports. */
960 asoc->peer.active_path = first;
961 asoc->peer.retran_path = second;
964 /* Hold a reference to an association. */
965 void sctp_association_hold(struct sctp_association *asoc)
967 atomic_inc(&asoc->base.refcnt);
970 /* Release a reference to an association and cleanup
971 * if there are no more references.
973 void sctp_association_put(struct sctp_association *asoc)
975 if (atomic_dec_and_test(&asoc->base.refcnt))
976 sctp_association_destroy(asoc);
979 /* Allocate the next TSN, Transmission Sequence Number, for the given
982 __u32 sctp_association_get_next_tsn(struct sctp_association *asoc)
984 /* From Section 1.6 Serial Number Arithmetic:
985 * Transmission Sequence Numbers wrap around when they reach
986 * 2**32 - 1. That is, the next TSN a DATA chunk MUST use
987 * after transmitting TSN = 2*32 - 1 is TSN = 0.
989 __u32 retval = asoc->next_tsn;
996 /* Compare two addresses to see if they match. Wildcard addresses
997 * only match themselves.
999 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1000 const union sctp_addr *ss2)
1004 af = sctp_get_af_specific(ss1->sa.sa_family);
1008 return af->cmp_addr(ss1, ss2);
1011 /* Return an ecne chunk to get prepended to a packet.
1012 * Note: We are sly and return a shared, prealloced chunk. FIXME:
1013 * No we don't, but we could/should.
1015 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc)
1017 struct sctp_chunk *chunk;
1019 /* Send ECNE if needed.
1020 * Not being able to allocate a chunk here is not deadly.
1022 if (asoc->need_ecne)
1023 chunk = sctp_make_ecne(asoc, asoc->last_ecne_tsn);
1031 * Find which transport this TSN was sent on.
1033 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *asoc,
1036 struct sctp_transport *active;
1037 struct sctp_transport *match;
1038 struct sctp_transport *transport;
1039 struct sctp_chunk *chunk;
1040 __be32 key = htonl(tsn);
1045 * FIXME: In general, find a more efficient data structure for
1050 * The general strategy is to search each transport's transmitted
1051 * list. Return which transport this TSN lives on.
1053 * Let's be hopeful and check the active_path first.
1054 * Another optimization would be to know if there is only one
1055 * outbound path and not have to look for the TSN at all.
1059 active = asoc->peer.active_path;
1061 list_for_each_entry(chunk, &active->transmitted,
1064 if (key == chunk->subh.data_hdr->tsn) {
1070 /* If not found, go search all the other transports. */
1071 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
1074 if (transport == active)
1076 list_for_each_entry(chunk, &transport->transmitted,
1078 if (key == chunk->subh.data_hdr->tsn) {
1088 /* Is this the association we are looking for? */
1089 struct sctp_transport *sctp_assoc_is_match(struct sctp_association *asoc,
1091 const union sctp_addr *laddr,
1092 const union sctp_addr *paddr)
1094 struct sctp_transport *transport;
1096 if ((htons(asoc->base.bind_addr.port) == laddr->v4.sin_port) &&
1097 (htons(asoc->peer.port) == paddr->v4.sin_port) &&
1098 net_eq(sock_net(asoc->base.sk), net)) {
1099 transport = sctp_assoc_lookup_paddr(asoc, paddr);
1103 if (sctp_bind_addr_match(&asoc->base.bind_addr, laddr,
1104 sctp_sk(asoc->base.sk)))
1113 /* Do delayed input processing. This is scheduled by sctp_rcv(). */
1114 static void sctp_assoc_bh_rcv(struct work_struct *work)
1116 struct sctp_association *asoc =
1117 container_of(work, struct sctp_association,
1118 base.inqueue.immediate);
1119 struct net *net = sock_net(asoc->base.sk);
1120 struct sctp_endpoint *ep;
1121 struct sctp_chunk *chunk;
1122 struct sctp_inq *inqueue;
1124 sctp_subtype_t subtype;
1127 /* The association should be held so we should be safe. */
1130 inqueue = &asoc->base.inqueue;
1131 sctp_association_hold(asoc);
1132 while (NULL != (chunk = sctp_inq_pop(inqueue))) {
1133 state = asoc->state;
1134 subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
1136 /* SCTP-AUTH, Section 6.3:
1137 * The receiver has a list of chunk types which it expects
1138 * to be received only after an AUTH-chunk. This list has
1139 * been sent to the peer during the association setup. It
1140 * MUST silently discard these chunks if they are not placed
1141 * after an AUTH chunk in the packet.
1143 if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth)
1146 /* Remember where the last DATA chunk came from so we
1147 * know where to send the SACK.
1149 if (sctp_chunk_is_data(chunk))
1150 asoc->peer.last_data_from = chunk->transport;
1152 SCTP_INC_STATS(net, SCTP_MIB_INCTRLCHUNKS);
1153 asoc->stats.ictrlchunks++;
1154 if (chunk->chunk_hdr->type == SCTP_CID_SACK)
1155 asoc->stats.isacks++;
1158 if (chunk->transport)
1159 chunk->transport->last_time_heard = jiffies;
1161 /* Run through the state machine. */
1162 error = sctp_do_sm(net, SCTP_EVENT_T_CHUNK, subtype,
1163 state, ep, asoc, chunk, GFP_ATOMIC);
1165 /* Check to see if the association is freed in response to
1166 * the incoming chunk. If so, get out of the while loop.
1168 if (asoc->base.dead)
1171 /* If there is an error on chunk, discard this packet. */
1173 chunk->pdiscard = 1;
1175 sctp_association_put(asoc);
1178 /* This routine moves an association from its old sk to a new sk. */
1179 void sctp_assoc_migrate(struct sctp_association *assoc, struct sock *newsk)
1181 struct sctp_sock *newsp = sctp_sk(newsk);
1182 struct sock *oldsk = assoc->base.sk;
1184 /* Delete the association from the old endpoint's list of
1187 list_del_init(&assoc->asocs);
1189 /* Decrement the backlog value for a TCP-style socket. */
1190 if (sctp_style(oldsk, TCP))
1191 oldsk->sk_ack_backlog--;
1193 /* Release references to the old endpoint and the sock. */
1194 sctp_endpoint_put(assoc->ep);
1195 sock_put(assoc->base.sk);
1197 /* Get a reference to the new endpoint. */
1198 assoc->ep = newsp->ep;
1199 sctp_endpoint_hold(assoc->ep);
1201 /* Get a reference to the new sock. */
1202 assoc->base.sk = newsk;
1203 sock_hold(assoc->base.sk);
1205 /* Add the association to the new endpoint's list of associations. */
1206 sctp_endpoint_add_asoc(newsp->ep, assoc);
1209 /* Update an association (possibly from unexpected COOKIE-ECHO processing). */
1210 void sctp_assoc_update(struct sctp_association *asoc,
1211 struct sctp_association *new)
1213 struct sctp_transport *trans;
1214 struct list_head *pos, *temp;
1216 /* Copy in new parameters of peer. */
1218 asoc->peer.rwnd = new->peer.rwnd;
1219 asoc->peer.sack_needed = new->peer.sack_needed;
1220 asoc->peer.i = new->peer.i;
1221 sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
1222 asoc->peer.i.initial_tsn, GFP_ATOMIC);
1224 /* Remove any peer addresses not present in the new association. */
1225 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1226 trans = list_entry(pos, struct sctp_transport, transports);
1227 if (!sctp_assoc_lookup_paddr(new, &trans->ipaddr)) {
1228 sctp_assoc_rm_peer(asoc, trans);
1232 if (asoc->state >= SCTP_STATE_ESTABLISHED)
1233 sctp_transport_reset(trans);
1236 /* If the case is A (association restart), use
1237 * initial_tsn as next_tsn. If the case is B, use
1238 * current next_tsn in case data sent to peer
1239 * has been discarded and needs retransmission.
1241 if (asoc->state >= SCTP_STATE_ESTABLISHED) {
1242 asoc->next_tsn = new->next_tsn;
1243 asoc->ctsn_ack_point = new->ctsn_ack_point;
1244 asoc->adv_peer_ack_point = new->adv_peer_ack_point;
1246 /* Reinitialize SSN for both local streams
1247 * and peer's streams.
1249 sctp_ssnmap_clear(asoc->ssnmap);
1251 /* Flush the ULP reassembly and ordered queue.
1252 * Any data there will now be stale and will
1255 sctp_ulpq_flush(&asoc->ulpq);
1257 /* reset the overall association error count so
1258 * that the restarted association doesn't get torn
1259 * down on the next retransmission timer.
1261 asoc->overall_error_count = 0;
1264 /* Add any peer addresses from the new association. */
1265 list_for_each_entry(trans, &new->peer.transport_addr_list,
1267 if (!sctp_assoc_lookup_paddr(asoc, &trans->ipaddr))
1268 sctp_assoc_add_peer(asoc, &trans->ipaddr,
1269 GFP_ATOMIC, trans->state);
1272 asoc->ctsn_ack_point = asoc->next_tsn - 1;
1273 asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
1274 if (!asoc->ssnmap) {
1275 /* Move the ssnmap. */
1276 asoc->ssnmap = new->ssnmap;
1280 if (!asoc->assoc_id) {
1281 /* get a new association id since we don't have one
1284 sctp_assoc_set_id(asoc, GFP_ATOMIC);
1288 /* SCTP-AUTH: Save the peer parameters from the new assocaitions
1289 * and also move the association shared keys over
1291 kfree(asoc->peer.peer_random);
1292 asoc->peer.peer_random = new->peer.peer_random;
1293 new->peer.peer_random = NULL;
1295 kfree(asoc->peer.peer_chunks);
1296 asoc->peer.peer_chunks = new->peer.peer_chunks;
1297 new->peer.peer_chunks = NULL;
1299 kfree(asoc->peer.peer_hmacs);
1300 asoc->peer.peer_hmacs = new->peer.peer_hmacs;
1301 new->peer.peer_hmacs = NULL;
1303 sctp_auth_key_put(asoc->asoc_shared_key);
1304 sctp_auth_asoc_init_active_key(asoc, GFP_ATOMIC);
1307 /* Update the retran path for sending a retransmitted packet.
1308 * Round-robin through the active transports, else round-robin
1309 * through the inactive transports as this is the next best thing
1312 void sctp_assoc_update_retran_path(struct sctp_association *asoc)
1314 struct sctp_transport *t, *next;
1315 struct list_head *head = &asoc->peer.transport_addr_list;
1316 struct list_head *pos;
1318 if (asoc->peer.transport_count == 1)
1321 /* Find the next transport in a round-robin fashion. */
1322 t = asoc->peer.retran_path;
1323 pos = &t->transports;
1327 /* Skip the head. */
1328 if (pos->next == head)
1333 t = list_entry(pos, struct sctp_transport, transports);
1335 /* We have exhausted the list, but didn't find any
1336 * other active transports. If so, use the next
1339 if (t == asoc->peer.retran_path) {
1344 /* Try to find an active transport. */
1346 if ((t->state == SCTP_ACTIVE) ||
1347 (t->state == SCTP_UNKNOWN)) {
1350 /* Keep track of the next transport in case
1351 * we don't find any active transport.
1353 if (t->state != SCTP_UNCONFIRMED && !next)
1359 asoc->peer.retran_path = t;
1361 t = asoc->peer.retran_path;
1363 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_update_retran_path:association"
1368 ntohs(t->ipaddr.v4.sin_port));
1371 /* Choose the transport for sending retransmit packet. */
1372 struct sctp_transport *sctp_assoc_choose_alter_transport(
1373 struct sctp_association *asoc, struct sctp_transport *last_sent_to)
1375 /* If this is the first time packet is sent, use the active path,
1376 * else use the retran path. If the last packet was sent over the
1377 * retran path, update the retran path and use it.
1380 return asoc->peer.active_path;
1382 if (last_sent_to == asoc->peer.retran_path)
1383 sctp_assoc_update_retran_path(asoc);
1384 return asoc->peer.retran_path;
1388 /* Update the association's pmtu and frag_point by going through all the
1389 * transports. This routine is called when a transport's PMTU has changed.
1391 void sctp_assoc_sync_pmtu(struct sock *sk, struct sctp_association *asoc)
1393 struct sctp_transport *t;
1399 /* Get the lowest pmtu of all the transports. */
1400 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1402 if (t->pmtu_pending && t->dst) {
1403 sctp_transport_update_pmtu(sk, t, dst_mtu(t->dst));
1404 t->pmtu_pending = 0;
1406 if (!pmtu || (t->pathmtu < pmtu))
1411 asoc->pathmtu = pmtu;
1412 asoc->frag_point = sctp_frag_point(asoc, pmtu);
1415 SCTP_DEBUG_PRINTK("%s: asoc:%p, pmtu:%d, frag_point:%d\n",
1416 __func__, asoc, asoc->pathmtu, asoc->frag_point);
1419 /* Should we send a SACK to update our peer? */
1420 static inline int sctp_peer_needs_update(struct sctp_association *asoc)
1422 struct net *net = sock_net(asoc->base.sk);
1423 switch (asoc->state) {
1424 case SCTP_STATE_ESTABLISHED:
1425 case SCTP_STATE_SHUTDOWN_PENDING:
1426 case SCTP_STATE_SHUTDOWN_RECEIVED:
1427 case SCTP_STATE_SHUTDOWN_SENT:
1428 if ((asoc->rwnd > asoc->a_rwnd) &&
1429 ((asoc->rwnd - asoc->a_rwnd) >= max_t(__u32,
1430 (asoc->base.sk->sk_rcvbuf >> net->sctp.rwnd_upd_shift),
1440 /* Increase asoc's rwnd by len and send any window update SACK if needed. */
1441 void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned int len)
1443 struct sctp_chunk *sack;
1444 struct timer_list *timer;
1446 if (asoc->rwnd_over) {
1447 if (asoc->rwnd_over >= len) {
1448 asoc->rwnd_over -= len;
1450 asoc->rwnd += (len - asoc->rwnd_over);
1451 asoc->rwnd_over = 0;
1457 /* If we had window pressure, start recovering it
1458 * once our rwnd had reached the accumulated pressure
1459 * threshold. The idea is to recover slowly, but up
1460 * to the initial advertised window.
1462 if (asoc->rwnd_press && asoc->rwnd >= asoc->rwnd_press) {
1463 int change = min(asoc->pathmtu, asoc->rwnd_press);
1464 asoc->rwnd += change;
1465 asoc->rwnd_press -= change;
1468 SCTP_DEBUG_PRINTK("%s: asoc %p rwnd increased by %d to (%u, %u) "
1469 "- %u\n", __func__, asoc, len, asoc->rwnd,
1470 asoc->rwnd_over, asoc->a_rwnd);
1472 /* Send a window update SACK if the rwnd has increased by at least the
1473 * minimum of the association's PMTU and half of the receive buffer.
1474 * The algorithm used is similar to the one described in
1475 * Section 4.2.3.3 of RFC 1122.
1477 if (sctp_peer_needs_update(asoc)) {
1478 asoc->a_rwnd = asoc->rwnd;
1479 SCTP_DEBUG_PRINTK("%s: Sending window update SACK- asoc: %p "
1480 "rwnd: %u a_rwnd: %u\n", __func__,
1481 asoc, asoc->rwnd, asoc->a_rwnd);
1482 sack = sctp_make_sack(asoc);
1486 asoc->peer.sack_needed = 0;
1488 sctp_outq_tail(&asoc->outqueue, sack);
1490 /* Stop the SACK timer. */
1491 timer = &asoc->timers[SCTP_EVENT_TIMEOUT_SACK];
1492 if (del_timer(timer))
1493 sctp_association_put(asoc);
1497 /* Decrease asoc's rwnd by len. */
1498 void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned int len)
1503 SCTP_ASSERT(asoc->rwnd, "rwnd zero", return);
1504 SCTP_ASSERT(!asoc->rwnd_over, "rwnd_over not zero", return);
1506 if (asoc->ep->rcvbuf_policy)
1507 rx_count = atomic_read(&asoc->rmem_alloc);
1509 rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc);
1511 /* If we've reached or overflowed our receive buffer, announce
1512 * a 0 rwnd if rwnd would still be positive. Store the
1513 * the pottential pressure overflow so that the window can be restored
1514 * back to original value.
1516 if (rx_count >= asoc->base.sk->sk_rcvbuf)
1519 if (asoc->rwnd >= len) {
1522 asoc->rwnd_press += asoc->rwnd;
1526 asoc->rwnd_over = len - asoc->rwnd;
1529 SCTP_DEBUG_PRINTK("%s: asoc %p rwnd decreased by %d to (%u, %u, %u)\n",
1530 __func__, asoc, len, asoc->rwnd,
1531 asoc->rwnd_over, asoc->rwnd_press);
1534 /* Build the bind address list for the association based on info from the
1535 * local endpoint and the remote peer.
1537 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc,
1538 sctp_scope_t scope, gfp_t gfp)
1542 /* Use scoping rules to determine the subset of addresses from
1545 flags = (PF_INET6 == asoc->base.sk->sk_family) ? SCTP_ADDR6_ALLOWED : 0;
1546 if (asoc->peer.ipv4_address)
1547 flags |= SCTP_ADDR4_PEERSUPP;
1548 if (asoc->peer.ipv6_address)
1549 flags |= SCTP_ADDR6_PEERSUPP;
1551 return sctp_bind_addr_copy(sock_net(asoc->base.sk),
1552 &asoc->base.bind_addr,
1553 &asoc->ep->base.bind_addr,
1557 /* Build the association's bind address list from the cookie. */
1558 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *asoc,
1559 struct sctp_cookie *cookie,
1562 int var_size2 = ntohs(cookie->peer_init->chunk_hdr.length);
1563 int var_size3 = cookie->raw_addr_list_len;
1564 __u8 *raw = (__u8 *)cookie->peer_init + var_size2;
1566 return sctp_raw_to_bind_addrs(&asoc->base.bind_addr, raw, var_size3,
1567 asoc->ep->base.bind_addr.port, gfp);
1570 /* Lookup laddr in the bind address list of an association. */
1571 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1572 const union sctp_addr *laddr)
1576 if ((asoc->base.bind_addr.port == ntohs(laddr->v4.sin_port)) &&
1577 sctp_bind_addr_match(&asoc->base.bind_addr, laddr,
1578 sctp_sk(asoc->base.sk)))
1584 /* Set an association id for a given association */
1585 int sctp_assoc_set_id(struct sctp_association *asoc, gfp_t gfp)
1587 bool preload = gfp & __GFP_WAIT;
1590 /* If the id is already assigned, keep it. */
1596 spin_lock_bh(&sctp_assocs_id_lock);
1597 /* 0 is not a valid assoc_id, must be >= 1 */
1598 ret = idr_alloc_cyclic(&sctp_assocs_id, asoc, 1, 0, GFP_NOWAIT);
1599 spin_unlock_bh(&sctp_assocs_id_lock);
1605 asoc->assoc_id = (sctp_assoc_t)ret;
1609 /* Free the ASCONF queue */
1610 static void sctp_assoc_free_asconf_queue(struct sctp_association *asoc)
1612 struct sctp_chunk *asconf;
1613 struct sctp_chunk *tmp;
1615 list_for_each_entry_safe(asconf, tmp, &asoc->addip_chunk_list, list) {
1616 list_del_init(&asconf->list);
1617 sctp_chunk_free(asconf);
1621 /* Free asconf_ack cache */
1622 static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc)
1624 struct sctp_chunk *ack;
1625 struct sctp_chunk *tmp;
1627 list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list,
1629 list_del_init(&ack->transmitted_list);
1630 sctp_chunk_free(ack);
1634 /* Clean up the ASCONF_ACK queue */
1635 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc)
1637 struct sctp_chunk *ack;
1638 struct sctp_chunk *tmp;
1640 /* We can remove all the entries from the queue up to
1641 * the "Peer-Sequence-Number".
1643 list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list,
1645 if (ack->subh.addip_hdr->serial ==
1646 htonl(asoc->peer.addip_serial))
1649 list_del_init(&ack->transmitted_list);
1650 sctp_chunk_free(ack);
1654 /* Find the ASCONF_ACK whose serial number matches ASCONF */
1655 struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
1656 const struct sctp_association *asoc,
1659 struct sctp_chunk *ack;
1661 /* Walk through the list of cached ASCONF-ACKs and find the
1662 * ack chunk whose serial number matches that of the request.
1664 list_for_each_entry(ack, &asoc->asconf_ack_list, transmitted_list) {
1665 if (ack->subh.addip_hdr->serial == serial) {
1666 sctp_chunk_hold(ack);
1674 void sctp_asconf_queue_teardown(struct sctp_association *asoc)
1676 /* Free any cached ASCONF_ACK chunk. */
1677 sctp_assoc_free_asconf_acks(asoc);
1679 /* Free the ASCONF queue. */
1680 sctp_assoc_free_asconf_queue(asoc);
1682 /* Free any cached ASCONF chunk. */
1683 if (asoc->addip_last_asconf)
1684 sctp_chunk_free(asoc->addip_last_asconf);