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);
100 asoc
->base
.dead
= false;
102 /* Initialize the bind addr area. */
103 sctp_bind_addr_init(&asoc
->base
.bind_addr
, ep
->base
.bind_addr
.port
);
105 asoc
->state
= SCTP_STATE_CLOSED
;
107 /* Set these values from the socket values, a conversion between
108 * millsecons to seconds/microseconds must also be done.
110 asoc
->cookie_life
.tv_sec
= sp
->assocparams
.sasoc_cookie_life
/ 1000;
111 asoc
->cookie_life
.tv_usec
= (sp
->assocparams
.sasoc_cookie_life
% 1000)
113 asoc
->frag_point
= 0;
114 asoc
->user_frag
= sp
->user_frag
;
116 /* Set the association max_retrans and RTO values from the
119 asoc
->max_retrans
= sp
->assocparams
.sasoc_asocmaxrxt
;
120 asoc
->pf_retrans
= net
->sctp
.pf_retrans
;
122 asoc
->rto_initial
= msecs_to_jiffies(sp
->rtoinfo
.srto_initial
);
123 asoc
->rto_max
= msecs_to_jiffies(sp
->rtoinfo
.srto_max
);
124 asoc
->rto_min
= msecs_to_jiffies(sp
->rtoinfo
.srto_min
);
126 asoc
->overall_error_count
= 0;
128 /* Initialize the association's heartbeat interval based on the
129 * sock configured value.
131 asoc
->hbinterval
= msecs_to_jiffies(sp
->hbinterval
);
133 /* Initialize path max retrans value. */
134 asoc
->pathmaxrxt
= sp
->pathmaxrxt
;
136 /* Initialize default path MTU. */
137 asoc
->pathmtu
= sp
->pathmtu
;
139 /* Set association default SACK delay */
140 asoc
->sackdelay
= msecs_to_jiffies(sp
->sackdelay
);
141 asoc
->sackfreq
= sp
->sackfreq
;
143 /* Set the association default flags controlling
144 * Heartbeat, SACK delay, and Path MTU Discovery.
146 asoc
->param_flags
= sp
->param_flags
;
148 /* Initialize the maximum mumber of new data packets that can be sent
151 asoc
->max_burst
= sp
->max_burst
;
153 /* initialize association timers */
154 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_NONE
] = 0;
155 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T1_COOKIE
] = asoc
->rto_initial
;
156 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T1_INIT
] = asoc
->rto_initial
;
157 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN
] = asoc
->rto_initial
;
158 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T3_RTX
] = 0;
159 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T4_RTO
] = 0;
161 /* sctpimpguide Section 2.12.2
162 * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the
163 * recommended value of 5 times 'RTO.Max'.
165 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD
]
168 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_HEARTBEAT
] = 0;
169 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_SACK
] = asoc
->sackdelay
;
170 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_AUTOCLOSE
] =
171 min_t(unsigned long, sp
->autoclose
, net
->sctp
.max_autoclose
) * HZ
;
173 /* Initializes the timers */
174 for (i
= SCTP_EVENT_TIMEOUT_NONE
; i
< SCTP_NUM_TIMEOUT_TYPES
; ++i
)
175 setup_timer(&asoc
->timers
[i
], sctp_timer_events
[i
],
176 (unsigned long)asoc
);
178 /* Pull default initialization values from the sock options.
179 * Note: This assumes that the values have already been
180 * validated in the sock.
182 asoc
->c
.sinit_max_instreams
= sp
->initmsg
.sinit_max_instreams
;
183 asoc
->c
.sinit_num_ostreams
= sp
->initmsg
.sinit_num_ostreams
;
184 asoc
->max_init_attempts
= sp
->initmsg
.sinit_max_attempts
;
186 asoc
->max_init_timeo
=
187 msecs_to_jiffies(sp
->initmsg
.sinit_max_init_timeo
);
189 /* Allocate storage for the ssnmap after the inbound and outbound
190 * streams have been negotiated during Init.
194 /* Set the local window size for receive.
195 * This is also the rcvbuf space per association.
196 * RFC 6 - A SCTP receiver MUST be able to receive a minimum of
197 * 1500 bytes in one SCTP packet.
199 if ((sk
->sk_rcvbuf
/2) < SCTP_DEFAULT_MINWINDOW
)
200 asoc
->rwnd
= SCTP_DEFAULT_MINWINDOW
;
202 asoc
->rwnd
= sk
->sk_rcvbuf
/2;
204 asoc
->a_rwnd
= asoc
->rwnd
;
207 asoc
->rwnd_press
= 0;
209 /* Use my own max window until I learn something better. */
210 asoc
->peer
.rwnd
= SCTP_DEFAULT_MAXWINDOW
;
212 /* Set the sndbuf size for transmit. */
213 asoc
->sndbuf_used
= 0;
215 /* Initialize the receive memory counter */
216 atomic_set(&asoc
->rmem_alloc
, 0);
218 init_waitqueue_head(&asoc
->wait
);
220 asoc
->c
.my_vtag
= sctp_generate_tag(ep
);
221 asoc
->peer
.i
.init_tag
= 0; /* INIT needs a vtag of 0. */
222 asoc
->c
.peer_vtag
= 0;
224 asoc
->c
.peer_ttag
= 0;
225 asoc
->c
.my_port
= ep
->base
.bind_addr
.port
;
227 asoc
->c
.initial_tsn
= sctp_generate_tsn(ep
);
229 asoc
->next_tsn
= asoc
->c
.initial_tsn
;
231 asoc
->ctsn_ack_point
= asoc
->next_tsn
- 1;
232 asoc
->adv_peer_ack_point
= asoc
->ctsn_ack_point
;
233 asoc
->highest_sacked
= asoc
->ctsn_ack_point
;
234 asoc
->last_cwr_tsn
= asoc
->ctsn_ack_point
;
235 asoc
->unack_data
= 0;
237 /* ADDIP Section 4.1 Asconf Chunk Procedures
239 * When an endpoint has an ASCONF signaled change to be sent to the
240 * remote endpoint it should do the following:
242 * A2) a serial number should be assigned to the chunk. The serial
243 * number SHOULD be a monotonically increasing number. The serial
244 * numbers SHOULD be initialized at the start of the
245 * association to the same value as the initial TSN.
247 asoc
->addip_serial
= asoc
->c
.initial_tsn
;
249 INIT_LIST_HEAD(&asoc
->addip_chunk_list
);
250 INIT_LIST_HEAD(&asoc
->asconf_ack_list
);
252 /* Make an empty list of remote transport addresses. */
253 INIT_LIST_HEAD(&asoc
->peer
.transport_addr_list
);
254 asoc
->peer
.transport_count
= 0;
256 /* RFC 2960 5.1 Normal Establishment of an Association
258 * After the reception of the first data chunk in an
259 * association the endpoint must immediately respond with a
260 * sack to acknowledge the data chunk. Subsequent
261 * acknowledgements should be done as described in Section
264 * [We implement this by telling a new association that it
265 * already received one packet.]
267 asoc
->peer
.sack_needed
= 1;
268 asoc
->peer
.sack_cnt
= 0;
269 asoc
->peer
.sack_generation
= 1;
271 /* Assume that the peer will tell us if he recognizes ASCONF
272 * as part of INIT exchange.
273 * The sctp_addip_noauth option is there for backward compatibilty
274 * and will revert old behavior.
276 asoc
->peer
.asconf_capable
= 0;
277 if (net
->sctp
.addip_noauth
)
278 asoc
->peer
.asconf_capable
= 1;
279 asoc
->asconf_addr_del_pending
= NULL
;
280 asoc
->src_out_of_asoc_ok
= 0;
281 asoc
->new_transport
= NULL
;
283 /* Create an input queue. */
284 sctp_inq_init(&asoc
->base
.inqueue
);
285 sctp_inq_set_th_handler(&asoc
->base
.inqueue
, sctp_assoc_bh_rcv
);
287 /* Create an output queue. */
288 sctp_outq_init(asoc
, &asoc
->outqueue
);
290 if (!sctp_ulpq_init(&asoc
->ulpq
, asoc
))
293 memset(&asoc
->peer
.tsn_map
, 0, sizeof(struct sctp_tsnmap
));
299 /* Assume that peer would support both address types unless we are
302 asoc
->peer
.ipv4_address
= 1;
303 if (asoc
->base
.sk
->sk_family
== PF_INET6
)
304 asoc
->peer
.ipv6_address
= 1;
305 INIT_LIST_HEAD(&asoc
->asocs
);
307 asoc
->autoclose
= sp
->autoclose
;
309 asoc
->default_stream
= sp
->default_stream
;
310 asoc
->default_ppid
= sp
->default_ppid
;
311 asoc
->default_flags
= sp
->default_flags
;
312 asoc
->default_context
= sp
->default_context
;
313 asoc
->default_timetolive
= sp
->default_timetolive
;
314 asoc
->default_rcv_context
= sp
->default_rcv_context
;
316 /* SCTP_GET_ASSOC_STATS COUNTERS */
317 memset(&asoc
->stats
, 0, sizeof(struct sctp_priv_assoc_stats
));
319 /* AUTH related initializations */
320 INIT_LIST_HEAD(&asoc
->endpoint_shared_keys
);
321 err
= sctp_auth_asoc_copy_shkeys(ep
, asoc
, gfp
);
325 asoc
->active_key_id
= ep
->active_key_id
;
326 asoc
->asoc_shared_key
= NULL
;
328 asoc
->default_hmac_id
= 0;
329 /* Save the hmacs and chunks list into this association */
330 if (ep
->auth_hmacs_list
)
331 memcpy(asoc
->c
.auth_hmacs
, ep
->auth_hmacs_list
,
332 ntohs(ep
->auth_hmacs_list
->param_hdr
.length
));
333 if (ep
->auth_chunk_list
)
334 memcpy(asoc
->c
.auth_chunks
, ep
->auth_chunk_list
,
335 ntohs(ep
->auth_chunk_list
->param_hdr
.length
));
337 /* Get the AUTH random number for this association */
338 p
= (sctp_paramhdr_t
*)asoc
->c
.auth_random
;
339 p
->type
= SCTP_PARAM_RANDOM
;
340 p
->length
= htons(sizeof(sctp_paramhdr_t
) + SCTP_AUTH_RANDOM_LENGTH
);
341 get_random_bytes(p
+1, SCTP_AUTH_RANDOM_LENGTH
);
346 sctp_endpoint_put(asoc
->ep
);
347 sock_put(asoc
->base
.sk
);
351 /* Allocate and initialize a new association */
352 struct sctp_association
*sctp_association_new(const struct sctp_endpoint
*ep
,
353 const struct sock
*sk
,
357 struct sctp_association
*asoc
;
359 asoc
= t_new(struct sctp_association
, gfp
);
363 if (!sctp_association_init(asoc
, ep
, sk
, scope
, gfp
))
366 SCTP_DBG_OBJCNT_INC(assoc
);
367 SCTP_DEBUG_PRINTK("Created asoc %p\n", asoc
);
377 /* Free this association if possible. There may still be users, so
378 * the actual deallocation may be delayed.
380 void sctp_association_free(struct sctp_association
*asoc
)
382 struct sock
*sk
= asoc
->base
.sk
;
383 struct sctp_transport
*transport
;
384 struct list_head
*pos
, *temp
;
387 /* Only real associations count against the endpoint, so
388 * don't bother for if this is a temporary association.
391 list_del(&asoc
->asocs
);
393 /* Decrement the backlog value for a TCP-style listening
396 if (sctp_style(sk
, TCP
) && sctp_sstate(sk
, LISTENING
))
397 sk
->sk_ack_backlog
--;
400 /* Mark as dead, so other users can know this structure is
403 asoc
->base
.dead
= true;
405 /* Dispose of any data lying around in the outqueue. */
406 sctp_outq_free(&asoc
->outqueue
);
408 /* Dispose of any pending messages for the upper layer. */
409 sctp_ulpq_free(&asoc
->ulpq
);
411 /* Dispose of any pending chunks on the inqueue. */
412 sctp_inq_free(&asoc
->base
.inqueue
);
414 sctp_tsnmap_free(&asoc
->peer
.tsn_map
);
416 /* Free ssnmap storage. */
417 sctp_ssnmap_free(asoc
->ssnmap
);
419 /* Clean up the bound address list. */
420 sctp_bind_addr_free(&asoc
->base
.bind_addr
);
422 /* Do we need to go through all of our timers and
423 * delete them? To be safe we will try to delete all, but we
424 * should be able to go through and make a guess based
427 for (i
= SCTP_EVENT_TIMEOUT_NONE
; i
< SCTP_NUM_TIMEOUT_TYPES
; ++i
) {
428 if (del_timer(&asoc
->timers
[i
]))
429 sctp_association_put(asoc
);
432 /* Free peer's cached cookie. */
433 kfree(asoc
->peer
.cookie
);
434 kfree(asoc
->peer
.peer_random
);
435 kfree(asoc
->peer
.peer_chunks
);
436 kfree(asoc
->peer
.peer_hmacs
);
438 /* Release the transport structures. */
439 list_for_each_safe(pos
, temp
, &asoc
->peer
.transport_addr_list
) {
440 transport
= list_entry(pos
, struct sctp_transport
, transports
);
442 sctp_transport_free(transport
);
445 asoc
->peer
.transport_count
= 0;
447 sctp_asconf_queue_teardown(asoc
);
449 /* Free pending address space being deleted */
450 if (asoc
->asconf_addr_del_pending
!= NULL
)
451 kfree(asoc
->asconf_addr_del_pending
);
453 /* AUTH - Free the endpoint shared keys */
454 sctp_auth_destroy_keys(&asoc
->endpoint_shared_keys
);
456 /* AUTH - Free the association shared key */
457 sctp_auth_key_put(asoc
->asoc_shared_key
);
459 sctp_association_put(asoc
);
462 /* Cleanup and free up an association. */
463 static void sctp_association_destroy(struct sctp_association
*asoc
)
465 SCTP_ASSERT(asoc
->base
.dead
, "Assoc is not dead", return);
467 sctp_endpoint_put(asoc
->ep
);
468 sock_put(asoc
->base
.sk
);
470 if (asoc
->assoc_id
!= 0) {
471 spin_lock_bh(&sctp_assocs_id_lock
);
472 idr_remove(&sctp_assocs_id
, asoc
->assoc_id
);
473 spin_unlock_bh(&sctp_assocs_id_lock
);
476 WARN_ON(atomic_read(&asoc
->rmem_alloc
));
479 SCTP_DBG_OBJCNT_DEC(assoc
);
482 /* Change the primary destination address for the peer. */
483 void sctp_assoc_set_primary(struct sctp_association
*asoc
,
484 struct sctp_transport
*transport
)
488 /* it's a changeover only if we already have a primary path
489 * that we are changing
491 if (asoc
->peer
.primary_path
!= NULL
&&
492 asoc
->peer
.primary_path
!= transport
)
495 asoc
->peer
.primary_path
= transport
;
497 /* Set a default msg_name for events. */
498 memcpy(&asoc
->peer
.primary_addr
, &transport
->ipaddr
,
499 sizeof(union sctp_addr
));
501 /* If the primary path is changing, assume that the
502 * user wants to use this new path.
504 if ((transport
->state
== SCTP_ACTIVE
) ||
505 (transport
->state
== SCTP_UNKNOWN
))
506 asoc
->peer
.active_path
= transport
;
509 * SFR-CACC algorithm:
510 * Upon the receipt of a request to change the primary
511 * destination address, on the data structure for the new
512 * primary destination, the sender MUST do the following:
514 * 1) If CHANGEOVER_ACTIVE is set, then there was a switch
515 * to this destination address earlier. The sender MUST set
516 * CYCLING_CHANGEOVER to indicate that this switch is a
517 * double switch to the same destination address.
519 * Really, only bother is we have data queued or outstanding on
522 if (!asoc
->outqueue
.outstanding_bytes
&& !asoc
->outqueue
.out_qlen
)
525 if (transport
->cacc
.changeover_active
)
526 transport
->cacc
.cycling_changeover
= changeover
;
528 /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that
529 * a changeover has occurred.
531 transport
->cacc
.changeover_active
= changeover
;
533 /* 3) The sender MUST store the next TSN to be sent in
534 * next_tsn_at_change.
536 transport
->cacc
.next_tsn_at_change
= asoc
->next_tsn
;
539 /* Remove a transport from an association. */
540 void sctp_assoc_rm_peer(struct sctp_association
*asoc
,
541 struct sctp_transport
*peer
)
543 struct list_head
*pos
;
544 struct sctp_transport
*transport
;
546 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_rm_peer:association %p addr: ",
550 ntohs(peer
->ipaddr
.v4
.sin_port
));
552 /* If we are to remove the current retran_path, update it
553 * to the next peer before removing this peer from the list.
555 if (asoc
->peer
.retran_path
== peer
)
556 sctp_assoc_update_retran_path(asoc
);
558 /* Remove this peer from the list. */
559 list_del_rcu(&peer
->transports
);
561 /* Get the first transport of asoc. */
562 pos
= asoc
->peer
.transport_addr_list
.next
;
563 transport
= list_entry(pos
, struct sctp_transport
, transports
);
565 /* Update any entries that match the peer to be deleted. */
566 if (asoc
->peer
.primary_path
== peer
)
567 sctp_assoc_set_primary(asoc
, transport
);
568 if (asoc
->peer
.active_path
== peer
)
569 asoc
->peer
.active_path
= transport
;
570 if (asoc
->peer
.retran_path
== peer
)
571 asoc
->peer
.retran_path
= transport
;
572 if (asoc
->peer
.last_data_from
== peer
)
573 asoc
->peer
.last_data_from
= transport
;
575 /* If we remove the transport an INIT was last sent to, set it to
576 * NULL. Combined with the update of the retran path above, this
577 * will cause the next INIT to be sent to the next available
578 * transport, maintaining the cycle.
580 if (asoc
->init_last_sent_to
== peer
)
581 asoc
->init_last_sent_to
= NULL
;
583 /* If we remove the transport an SHUTDOWN was last sent to, set it
584 * to NULL. Combined with the update of the retran path above, this
585 * will cause the next SHUTDOWN to be sent to the next available
586 * transport, maintaining the cycle.
588 if (asoc
->shutdown_last_sent_to
== peer
)
589 asoc
->shutdown_last_sent_to
= NULL
;
591 /* If we remove the transport an ASCONF was last sent to, set it to
594 if (asoc
->addip_last_asconf
&&
595 asoc
->addip_last_asconf
->transport
== peer
)
596 asoc
->addip_last_asconf
->transport
= NULL
;
598 /* If we have something on the transmitted list, we have to
599 * save it off. The best place is the active path.
601 if (!list_empty(&peer
->transmitted
)) {
602 struct sctp_transport
*active
= asoc
->peer
.active_path
;
603 struct sctp_chunk
*ch
;
605 /* Reset the transport of each chunk on this list */
606 list_for_each_entry(ch
, &peer
->transmitted
,
608 ch
->transport
= NULL
;
609 ch
->rtt_in_progress
= 0;
612 list_splice_tail_init(&peer
->transmitted
,
613 &active
->transmitted
);
615 /* Start a T3 timer here in case it wasn't running so
616 * that these migrated packets have a chance to get
619 if (!timer_pending(&active
->T3_rtx_timer
))
620 if (!mod_timer(&active
->T3_rtx_timer
,
621 jiffies
+ active
->rto
))
622 sctp_transport_hold(active
);
625 asoc
->peer
.transport_count
--;
627 sctp_transport_free(peer
);
630 /* Add a transport address to an association. */
631 struct sctp_transport
*sctp_assoc_add_peer(struct sctp_association
*asoc
,
632 const union sctp_addr
*addr
,
634 const int peer_state
)
636 struct net
*net
= sock_net(asoc
->base
.sk
);
637 struct sctp_transport
*peer
;
638 struct sctp_sock
*sp
;
641 sp
= sctp_sk(asoc
->base
.sk
);
643 /* AF_INET and AF_INET6 share common port field. */
644 port
= ntohs(addr
->v4
.sin_port
);
646 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_add_peer:association %p addr: ",
647 " port: %d state:%d\n",
653 /* Set the port if it has not been set yet. */
654 if (0 == asoc
->peer
.port
)
655 asoc
->peer
.port
= port
;
657 /* Check to see if this is a duplicate. */
658 peer
= sctp_assoc_lookup_paddr(asoc
, addr
);
660 /* An UNKNOWN state is only set on transports added by
661 * user in sctp_connectx() call. Such transports should be
662 * considered CONFIRMED per RFC 4960, Section 5.4.
664 if (peer
->state
== SCTP_UNKNOWN
) {
665 peer
->state
= SCTP_ACTIVE
;
670 peer
= sctp_transport_new(net
, addr
, gfp
);
674 sctp_transport_set_owner(peer
, asoc
);
676 /* Initialize the peer's heartbeat interval based on the
677 * association configured value.
679 peer
->hbinterval
= asoc
->hbinterval
;
681 /* Set the path max_retrans. */
682 peer
->pathmaxrxt
= asoc
->pathmaxrxt
;
684 /* And the partial failure retrnas threshold */
685 peer
->pf_retrans
= asoc
->pf_retrans
;
687 /* Initialize the peer's SACK delay timeout based on the
688 * association configured value.
690 peer
->sackdelay
= asoc
->sackdelay
;
691 peer
->sackfreq
= asoc
->sackfreq
;
693 /* Enable/disable heartbeat, SACK delay, and path MTU discovery
694 * based on association setting.
696 peer
->param_flags
= asoc
->param_flags
;
698 sctp_transport_route(peer
, NULL
, sp
);
700 /* Initialize the pmtu of the transport. */
701 if (peer
->param_flags
& SPP_PMTUD_DISABLE
) {
703 peer
->pathmtu
= asoc
->pathmtu
;
705 peer
->pathmtu
= SCTP_DEFAULT_MAXSEGMENT
;
708 /* If this is the first transport addr on this association,
709 * initialize the association PMTU to the peer's PMTU.
710 * If not and the current association PMTU is higher than the new
711 * peer's PMTU, reset the association PMTU to the new peer's PMTU.
714 asoc
->pathmtu
= min_t(int, peer
->pathmtu
, asoc
->pathmtu
);
716 asoc
->pathmtu
= peer
->pathmtu
;
718 SCTP_DEBUG_PRINTK("sctp_assoc_add_peer:association %p PMTU set to "
719 "%d\n", asoc
, asoc
->pathmtu
);
720 peer
->pmtu_pending
= 0;
722 asoc
->frag_point
= sctp_frag_point(asoc
, asoc
->pathmtu
);
724 /* The asoc->peer.port might not be meaningful yet, but
725 * initialize the packet structure anyway.
727 sctp_packet_init(&peer
->packet
, peer
, asoc
->base
.bind_addr
.port
,
732 * o The initial cwnd before DATA transmission or after a sufficiently
733 * long idle period MUST be set to
734 * min(4*MTU, max(2*MTU, 4380 bytes))
736 * o The initial value of ssthresh MAY be arbitrarily high
737 * (for example, implementations MAY use the size of the
738 * receiver advertised window).
740 peer
->cwnd
= min(4*asoc
->pathmtu
, max_t(__u32
, 2*asoc
->pathmtu
, 4380));
742 /* At this point, we may not have the receiver's advertised window,
743 * so initialize ssthresh to the default value and it will be set
744 * later when we process the INIT.
746 peer
->ssthresh
= SCTP_DEFAULT_MAXWINDOW
;
748 peer
->partial_bytes_acked
= 0;
749 peer
->flight_size
= 0;
750 peer
->burst_limited
= 0;
752 /* Set the transport's RTO.initial value */
753 peer
->rto
= asoc
->rto_initial
;
754 sctp_max_rto(asoc
, peer
);
756 /* Set the peer's active state. */
757 peer
->state
= peer_state
;
759 /* Attach the remote transport to our asoc. */
760 list_add_tail_rcu(&peer
->transports
, &asoc
->peer
.transport_addr_list
);
761 asoc
->peer
.transport_count
++;
763 /* If we do not yet have a primary path, set one. */
764 if (!asoc
->peer
.primary_path
) {
765 sctp_assoc_set_primary(asoc
, peer
);
766 asoc
->peer
.retran_path
= peer
;
769 if (asoc
->peer
.active_path
== asoc
->peer
.retran_path
&&
770 peer
->state
!= SCTP_UNCONFIRMED
) {
771 asoc
->peer
.retran_path
= peer
;
777 /* Delete a transport address from an association. */
778 void sctp_assoc_del_peer(struct sctp_association
*asoc
,
779 const union sctp_addr
*addr
)
781 struct list_head
*pos
;
782 struct list_head
*temp
;
783 struct sctp_transport
*transport
;
785 list_for_each_safe(pos
, temp
, &asoc
->peer
.transport_addr_list
) {
786 transport
= list_entry(pos
, struct sctp_transport
, transports
);
787 if (sctp_cmp_addr_exact(addr
, &transport
->ipaddr
)) {
788 /* Do book keeping for removing the peer and free it. */
789 sctp_assoc_rm_peer(asoc
, transport
);
795 /* Lookup a transport by address. */
796 struct sctp_transport
*sctp_assoc_lookup_paddr(
797 const struct sctp_association
*asoc
,
798 const union sctp_addr
*address
)
800 struct sctp_transport
*t
;
802 /* Cycle through all transports searching for a peer address. */
804 list_for_each_entry(t
, &asoc
->peer
.transport_addr_list
,
806 if (sctp_cmp_addr_exact(address
, &t
->ipaddr
))
813 /* Remove all transports except a give one */
814 void sctp_assoc_del_nonprimary_peers(struct sctp_association
*asoc
,
815 struct sctp_transport
*primary
)
817 struct sctp_transport
*temp
;
818 struct sctp_transport
*t
;
820 list_for_each_entry_safe(t
, temp
, &asoc
->peer
.transport_addr_list
,
822 /* if the current transport is not the primary one, delete it */
824 sctp_assoc_rm_peer(asoc
, t
);
828 /* Engage in transport control operations.
829 * Mark the transport up or down and send a notification to the user.
830 * Select and update the new active and retran paths.
832 void sctp_assoc_control_transport(struct sctp_association
*asoc
,
833 struct sctp_transport
*transport
,
834 sctp_transport_cmd_t command
,
835 sctp_sn_error_t error
)
837 struct sctp_transport
*t
= NULL
;
838 struct sctp_transport
*first
;
839 struct sctp_transport
*second
;
840 struct sctp_ulpevent
*event
;
841 struct sockaddr_storage addr
;
843 bool ulp_notify
= true;
845 /* Record the transition on the transport. */
847 case SCTP_TRANSPORT_UP
:
848 /* If we are moving from UNCONFIRMED state due
849 * to heartbeat success, report the SCTP_ADDR_CONFIRMED
850 * state to the user, otherwise report SCTP_ADDR_AVAILABLE.
852 if (SCTP_UNCONFIRMED
== transport
->state
&&
853 SCTP_HEARTBEAT_SUCCESS
== error
)
854 spc_state
= SCTP_ADDR_CONFIRMED
;
856 spc_state
= SCTP_ADDR_AVAILABLE
;
857 /* Don't inform ULP about transition from PF to
858 * active state and set cwnd to 1, see SCTP
859 * Quick failover draft section 5.1, point 5
861 if (transport
->state
== SCTP_PF
) {
865 transport
->state
= SCTP_ACTIVE
;
868 case SCTP_TRANSPORT_DOWN
:
869 /* If the transport was never confirmed, do not transition it
870 * to inactive state. Also, release the cached route since
871 * there may be a better route next time.
873 if (transport
->state
!= SCTP_UNCONFIRMED
)
874 transport
->state
= SCTP_INACTIVE
;
876 dst_release(transport
->dst
);
877 transport
->dst
= NULL
;
880 spc_state
= SCTP_ADDR_UNREACHABLE
;
883 case SCTP_TRANSPORT_PF
:
884 transport
->state
= SCTP_PF
;
892 /* Generate and send a SCTP_PEER_ADDR_CHANGE notification to the
896 memset(&addr
, 0, sizeof(struct sockaddr_storage
));
897 memcpy(&addr
, &transport
->ipaddr
,
898 transport
->af_specific
->sockaddr_len
);
899 event
= sctp_ulpevent_make_peer_addr_change(asoc
, &addr
,
900 0, spc_state
, error
, GFP_ATOMIC
);
902 sctp_ulpq_tail_event(&asoc
->ulpq
, event
);
905 /* Select new active and retran paths. */
907 /* Look for the two most recently used active transports.
909 * This code produces the wrong ordering whenever jiffies
910 * rolls over, but we still get usable transports, so we don't
913 first
= NULL
; second
= NULL
;
915 list_for_each_entry(t
, &asoc
->peer
.transport_addr_list
,
918 if ((t
->state
== SCTP_INACTIVE
) ||
919 (t
->state
== SCTP_UNCONFIRMED
) ||
920 (t
->state
== SCTP_PF
))
922 if (!first
|| t
->last_time_heard
> first
->last_time_heard
) {
926 if (!second
|| t
->last_time_heard
> second
->last_time_heard
)
930 /* RFC 2960 6.4 Multi-Homed SCTP Endpoints
932 * By default, an endpoint should always transmit to the
933 * primary path, unless the SCTP user explicitly specifies the
934 * destination transport address (and possibly source
935 * transport address) to use.
937 * [If the primary is active but not most recent, bump the most
938 * recently used transport.]
940 if (((asoc
->peer
.primary_path
->state
== SCTP_ACTIVE
) ||
941 (asoc
->peer
.primary_path
->state
== SCTP_UNKNOWN
)) &&
942 first
!= asoc
->peer
.primary_path
) {
944 first
= asoc
->peer
.primary_path
;
947 /* If we failed to find a usable transport, just camp on the
948 * primary, even if it is inactive.
951 first
= asoc
->peer
.primary_path
;
952 second
= asoc
->peer
.primary_path
;
955 /* Set the active and retran transports. */
956 asoc
->peer
.active_path
= first
;
957 asoc
->peer
.retran_path
= second
;
960 /* Hold a reference to an association. */
961 void sctp_association_hold(struct sctp_association
*asoc
)
963 atomic_inc(&asoc
->base
.refcnt
);
966 /* Release a reference to an association and cleanup
967 * if there are no more references.
969 void sctp_association_put(struct sctp_association
*asoc
)
971 if (atomic_dec_and_test(&asoc
->base
.refcnt
))
972 sctp_association_destroy(asoc
);
975 /* Allocate the next TSN, Transmission Sequence Number, for the given
978 __u32
sctp_association_get_next_tsn(struct sctp_association
*asoc
)
980 /* From Section 1.6 Serial Number Arithmetic:
981 * Transmission Sequence Numbers wrap around when they reach
982 * 2**32 - 1. That is, the next TSN a DATA chunk MUST use
983 * after transmitting TSN = 2*32 - 1 is TSN = 0.
985 __u32 retval
= asoc
->next_tsn
;
992 /* Compare two addresses to see if they match. Wildcard addresses
993 * only match themselves.
995 int sctp_cmp_addr_exact(const union sctp_addr
*ss1
,
996 const union sctp_addr
*ss2
)
1000 af
= sctp_get_af_specific(ss1
->sa
.sa_family
);
1004 return af
->cmp_addr(ss1
, ss2
);
1007 /* Return an ecne chunk to get prepended to a packet.
1008 * Note: We are sly and return a shared, prealloced chunk. FIXME:
1009 * No we don't, but we could/should.
1011 struct sctp_chunk
*sctp_get_ecne_prepend(struct sctp_association
*asoc
)
1013 struct sctp_chunk
*chunk
;
1015 /* Send ECNE if needed.
1016 * Not being able to allocate a chunk here is not deadly.
1018 if (asoc
->need_ecne
)
1019 chunk
= sctp_make_ecne(asoc
, asoc
->last_ecne_tsn
);
1027 * Find which transport this TSN was sent on.
1029 struct sctp_transport
*sctp_assoc_lookup_tsn(struct sctp_association
*asoc
,
1032 struct sctp_transport
*active
;
1033 struct sctp_transport
*match
;
1034 struct sctp_transport
*transport
;
1035 struct sctp_chunk
*chunk
;
1036 __be32 key
= htonl(tsn
);
1041 * FIXME: In general, find a more efficient data structure for
1046 * The general strategy is to search each transport's transmitted
1047 * list. Return which transport this TSN lives on.
1049 * Let's be hopeful and check the active_path first.
1050 * Another optimization would be to know if there is only one
1051 * outbound path and not have to look for the TSN at all.
1055 active
= asoc
->peer
.active_path
;
1057 list_for_each_entry(chunk
, &active
->transmitted
,
1060 if (key
== chunk
->subh
.data_hdr
->tsn
) {
1066 /* If not found, go search all the other transports. */
1067 list_for_each_entry(transport
, &asoc
->peer
.transport_addr_list
,
1070 if (transport
== active
)
1072 list_for_each_entry(chunk
, &transport
->transmitted
,
1074 if (key
== chunk
->subh
.data_hdr
->tsn
) {
1084 /* Is this the association we are looking for? */
1085 struct sctp_transport
*sctp_assoc_is_match(struct sctp_association
*asoc
,
1087 const union sctp_addr
*laddr
,
1088 const union sctp_addr
*paddr
)
1090 struct sctp_transport
*transport
;
1092 if ((htons(asoc
->base
.bind_addr
.port
) == laddr
->v4
.sin_port
) &&
1093 (htons(asoc
->peer
.port
) == paddr
->v4
.sin_port
) &&
1094 net_eq(sock_net(asoc
->base
.sk
), net
)) {
1095 transport
= sctp_assoc_lookup_paddr(asoc
, paddr
);
1099 if (sctp_bind_addr_match(&asoc
->base
.bind_addr
, laddr
,
1100 sctp_sk(asoc
->base
.sk
)))
1109 /* Do delayed input processing. This is scheduled by sctp_rcv(). */
1110 static void sctp_assoc_bh_rcv(struct work_struct
*work
)
1112 struct sctp_association
*asoc
=
1113 container_of(work
, struct sctp_association
,
1114 base
.inqueue
.immediate
);
1115 struct net
*net
= sock_net(asoc
->base
.sk
);
1116 struct sctp_endpoint
*ep
;
1117 struct sctp_chunk
*chunk
;
1118 struct sctp_inq
*inqueue
;
1120 sctp_subtype_t subtype
;
1123 /* The association should be held so we should be safe. */
1126 inqueue
= &asoc
->base
.inqueue
;
1127 sctp_association_hold(asoc
);
1128 while (NULL
!= (chunk
= sctp_inq_pop(inqueue
))) {
1129 state
= asoc
->state
;
1130 subtype
= SCTP_ST_CHUNK(chunk
->chunk_hdr
->type
);
1132 /* SCTP-AUTH, Section 6.3:
1133 * The receiver has a list of chunk types which it expects
1134 * to be received only after an AUTH-chunk. This list has
1135 * been sent to the peer during the association setup. It
1136 * MUST silently discard these chunks if they are not placed
1137 * after an AUTH chunk in the packet.
1139 if (sctp_auth_recv_cid(subtype
.chunk
, asoc
) && !chunk
->auth
)
1142 /* Remember where the last DATA chunk came from so we
1143 * know where to send the SACK.
1145 if (sctp_chunk_is_data(chunk
))
1146 asoc
->peer
.last_data_from
= chunk
->transport
;
1148 SCTP_INC_STATS(net
, SCTP_MIB_INCTRLCHUNKS
);
1149 asoc
->stats
.ictrlchunks
++;
1150 if (chunk
->chunk_hdr
->type
== SCTP_CID_SACK
)
1151 asoc
->stats
.isacks
++;
1154 if (chunk
->transport
)
1155 chunk
->transport
->last_time_heard
= jiffies
;
1157 /* Run through the state machine. */
1158 error
= sctp_do_sm(net
, SCTP_EVENT_T_CHUNK
, subtype
,
1159 state
, ep
, asoc
, chunk
, GFP_ATOMIC
);
1161 /* Check to see if the association is freed in response to
1162 * the incoming chunk. If so, get out of the while loop.
1164 if (asoc
->base
.dead
)
1167 /* If there is an error on chunk, discard this packet. */
1169 chunk
->pdiscard
= 1;
1171 sctp_association_put(asoc
);
1174 /* This routine moves an association from its old sk to a new sk. */
1175 void sctp_assoc_migrate(struct sctp_association
*assoc
, struct sock
*newsk
)
1177 struct sctp_sock
*newsp
= sctp_sk(newsk
);
1178 struct sock
*oldsk
= assoc
->base
.sk
;
1180 /* Delete the association from the old endpoint's list of
1183 list_del_init(&assoc
->asocs
);
1185 /* Decrement the backlog value for a TCP-style socket. */
1186 if (sctp_style(oldsk
, TCP
))
1187 oldsk
->sk_ack_backlog
--;
1189 /* Release references to the old endpoint and the sock. */
1190 sctp_endpoint_put(assoc
->ep
);
1191 sock_put(assoc
->base
.sk
);
1193 /* Get a reference to the new endpoint. */
1194 assoc
->ep
= newsp
->ep
;
1195 sctp_endpoint_hold(assoc
->ep
);
1197 /* Get a reference to the new sock. */
1198 assoc
->base
.sk
= newsk
;
1199 sock_hold(assoc
->base
.sk
);
1201 /* Add the association to the new endpoint's list of associations. */
1202 sctp_endpoint_add_asoc(newsp
->ep
, assoc
);
1205 /* Update an association (possibly from unexpected COOKIE-ECHO processing). */
1206 void sctp_assoc_update(struct sctp_association
*asoc
,
1207 struct sctp_association
*new)
1209 struct sctp_transport
*trans
;
1210 struct list_head
*pos
, *temp
;
1212 /* Copy in new parameters of peer. */
1214 asoc
->peer
.rwnd
= new->peer
.rwnd
;
1215 asoc
->peer
.sack_needed
= new->peer
.sack_needed
;
1216 asoc
->peer
.i
= new->peer
.i
;
1217 sctp_tsnmap_init(&asoc
->peer
.tsn_map
, SCTP_TSN_MAP_INITIAL
,
1218 asoc
->peer
.i
.initial_tsn
, GFP_ATOMIC
);
1220 /* Remove any peer addresses not present in the new association. */
1221 list_for_each_safe(pos
, temp
, &asoc
->peer
.transport_addr_list
) {
1222 trans
= list_entry(pos
, struct sctp_transport
, transports
);
1223 if (!sctp_assoc_lookup_paddr(new, &trans
->ipaddr
)) {
1224 sctp_assoc_rm_peer(asoc
, trans
);
1228 if (asoc
->state
>= SCTP_STATE_ESTABLISHED
)
1229 sctp_transport_reset(trans
);
1232 /* If the case is A (association restart), use
1233 * initial_tsn as next_tsn. If the case is B, use
1234 * current next_tsn in case data sent to peer
1235 * has been discarded and needs retransmission.
1237 if (asoc
->state
>= SCTP_STATE_ESTABLISHED
) {
1238 asoc
->next_tsn
= new->next_tsn
;
1239 asoc
->ctsn_ack_point
= new->ctsn_ack_point
;
1240 asoc
->adv_peer_ack_point
= new->adv_peer_ack_point
;
1242 /* Reinitialize SSN for both local streams
1243 * and peer's streams.
1245 sctp_ssnmap_clear(asoc
->ssnmap
);
1247 /* Flush the ULP reassembly and ordered queue.
1248 * Any data there will now be stale and will
1251 sctp_ulpq_flush(&asoc
->ulpq
);
1253 /* reset the overall association error count so
1254 * that the restarted association doesn't get torn
1255 * down on the next retransmission timer.
1257 asoc
->overall_error_count
= 0;
1260 /* Add any peer addresses from the new association. */
1261 list_for_each_entry(trans
, &new->peer
.transport_addr_list
,
1263 if (!sctp_assoc_lookup_paddr(asoc
, &trans
->ipaddr
))
1264 sctp_assoc_add_peer(asoc
, &trans
->ipaddr
,
1265 GFP_ATOMIC
, trans
->state
);
1268 asoc
->ctsn_ack_point
= asoc
->next_tsn
- 1;
1269 asoc
->adv_peer_ack_point
= asoc
->ctsn_ack_point
;
1270 if (!asoc
->ssnmap
) {
1271 /* Move the ssnmap. */
1272 asoc
->ssnmap
= new->ssnmap
;
1276 if (!asoc
->assoc_id
) {
1277 /* get a new association id since we don't have one
1280 sctp_assoc_set_id(asoc
, GFP_ATOMIC
);
1284 /* SCTP-AUTH: Save the peer parameters from the new assocaitions
1285 * and also move the association shared keys over
1287 kfree(asoc
->peer
.peer_random
);
1288 asoc
->peer
.peer_random
= new->peer
.peer_random
;
1289 new->peer
.peer_random
= NULL
;
1291 kfree(asoc
->peer
.peer_chunks
);
1292 asoc
->peer
.peer_chunks
= new->peer
.peer_chunks
;
1293 new->peer
.peer_chunks
= NULL
;
1295 kfree(asoc
->peer
.peer_hmacs
);
1296 asoc
->peer
.peer_hmacs
= new->peer
.peer_hmacs
;
1297 new->peer
.peer_hmacs
= NULL
;
1299 sctp_auth_key_put(asoc
->asoc_shared_key
);
1300 sctp_auth_asoc_init_active_key(asoc
, GFP_ATOMIC
);
1303 /* Update the retran path for sending a retransmitted packet.
1304 * Round-robin through the active transports, else round-robin
1305 * through the inactive transports as this is the next best thing
1308 void sctp_assoc_update_retran_path(struct sctp_association
*asoc
)
1310 struct sctp_transport
*t
, *next
;
1311 struct list_head
*head
= &asoc
->peer
.transport_addr_list
;
1312 struct list_head
*pos
;
1314 if (asoc
->peer
.transport_count
== 1)
1317 /* Find the next transport in a round-robin fashion. */
1318 t
= asoc
->peer
.retran_path
;
1319 pos
= &t
->transports
;
1323 /* Skip the head. */
1324 if (pos
->next
== head
)
1329 t
= list_entry(pos
, struct sctp_transport
, transports
);
1331 /* We have exhausted the list, but didn't find any
1332 * other active transports. If so, use the next
1335 if (t
== asoc
->peer
.retran_path
) {
1340 /* Try to find an active transport. */
1342 if ((t
->state
== SCTP_ACTIVE
) ||
1343 (t
->state
== SCTP_UNKNOWN
)) {
1346 /* Keep track of the next transport in case
1347 * we don't find any active transport.
1349 if (t
->state
!= SCTP_UNCONFIRMED
&& !next
)
1355 asoc
->peer
.retran_path
= t
;
1357 t
= asoc
->peer
.retran_path
;
1359 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_update_retran_path:association"
1364 ntohs(t
->ipaddr
.v4
.sin_port
));
1367 /* Choose the transport for sending retransmit packet. */
1368 struct sctp_transport
*sctp_assoc_choose_alter_transport(
1369 struct sctp_association
*asoc
, struct sctp_transport
*last_sent_to
)
1371 /* If this is the first time packet is sent, use the active path,
1372 * else use the retran path. If the last packet was sent over the
1373 * retran path, update the retran path and use it.
1376 return asoc
->peer
.active_path
;
1378 if (last_sent_to
== asoc
->peer
.retran_path
)
1379 sctp_assoc_update_retran_path(asoc
);
1380 return asoc
->peer
.retran_path
;
1384 /* Update the association's pmtu and frag_point by going through all the
1385 * transports. This routine is called when a transport's PMTU has changed.
1387 void sctp_assoc_sync_pmtu(struct sock
*sk
, struct sctp_association
*asoc
)
1389 struct sctp_transport
*t
;
1395 /* Get the lowest pmtu of all the transports. */
1396 list_for_each_entry(t
, &asoc
->peer
.transport_addr_list
,
1398 if (t
->pmtu_pending
&& t
->dst
) {
1399 sctp_transport_update_pmtu(sk
, t
, dst_mtu(t
->dst
));
1400 t
->pmtu_pending
= 0;
1402 if (!pmtu
|| (t
->pathmtu
< pmtu
))
1407 asoc
->pathmtu
= pmtu
;
1408 asoc
->frag_point
= sctp_frag_point(asoc
, pmtu
);
1411 SCTP_DEBUG_PRINTK("%s: asoc:%p, pmtu:%d, frag_point:%d\n",
1412 __func__
, asoc
, asoc
->pathmtu
, asoc
->frag_point
);
1415 /* Should we send a SACK to update our peer? */
1416 static inline int sctp_peer_needs_update(struct sctp_association
*asoc
)
1418 struct net
*net
= sock_net(asoc
->base
.sk
);
1419 switch (asoc
->state
) {
1420 case SCTP_STATE_ESTABLISHED
:
1421 case SCTP_STATE_SHUTDOWN_PENDING
:
1422 case SCTP_STATE_SHUTDOWN_RECEIVED
:
1423 case SCTP_STATE_SHUTDOWN_SENT
:
1424 if ((asoc
->rwnd
> asoc
->a_rwnd
) &&
1425 ((asoc
->rwnd
- asoc
->a_rwnd
) >= max_t(__u32
,
1426 (asoc
->base
.sk
->sk_rcvbuf
>> net
->sctp
.rwnd_upd_shift
),
1436 /* Increase asoc's rwnd by len and send any window update SACK if needed. */
1437 void sctp_assoc_rwnd_increase(struct sctp_association
*asoc
, unsigned int len
)
1439 struct sctp_chunk
*sack
;
1440 struct timer_list
*timer
;
1442 if (asoc
->rwnd_over
) {
1443 if (asoc
->rwnd_over
>= len
) {
1444 asoc
->rwnd_over
-= len
;
1446 asoc
->rwnd
+= (len
- asoc
->rwnd_over
);
1447 asoc
->rwnd_over
= 0;
1453 /* If we had window pressure, start recovering it
1454 * once our rwnd had reached the accumulated pressure
1455 * threshold. The idea is to recover slowly, but up
1456 * to the initial advertised window.
1458 if (asoc
->rwnd_press
&& asoc
->rwnd
>= asoc
->rwnd_press
) {
1459 int change
= min(asoc
->pathmtu
, asoc
->rwnd_press
);
1460 asoc
->rwnd
+= change
;
1461 asoc
->rwnd_press
-= change
;
1464 SCTP_DEBUG_PRINTK("%s: asoc %p rwnd increased by %d to (%u, %u) "
1465 "- %u\n", __func__
, asoc
, len
, asoc
->rwnd
,
1466 asoc
->rwnd_over
, asoc
->a_rwnd
);
1468 /* Send a window update SACK if the rwnd has increased by at least the
1469 * minimum of the association's PMTU and half of the receive buffer.
1470 * The algorithm used is similar to the one described in
1471 * Section 4.2.3.3 of RFC 1122.
1473 if (sctp_peer_needs_update(asoc
)) {
1474 asoc
->a_rwnd
= asoc
->rwnd
;
1475 SCTP_DEBUG_PRINTK("%s: Sending window update SACK- asoc: %p "
1476 "rwnd: %u a_rwnd: %u\n", __func__
,
1477 asoc
, asoc
->rwnd
, asoc
->a_rwnd
);
1478 sack
= sctp_make_sack(asoc
);
1482 asoc
->peer
.sack_needed
= 0;
1484 sctp_outq_tail(&asoc
->outqueue
, sack
);
1486 /* Stop the SACK timer. */
1487 timer
= &asoc
->timers
[SCTP_EVENT_TIMEOUT_SACK
];
1488 if (del_timer(timer
))
1489 sctp_association_put(asoc
);
1493 /* Decrease asoc's rwnd by len. */
1494 void sctp_assoc_rwnd_decrease(struct sctp_association
*asoc
, unsigned int len
)
1499 SCTP_ASSERT(asoc
->rwnd
, "rwnd zero", return);
1500 SCTP_ASSERT(!asoc
->rwnd_over
, "rwnd_over not zero", return);
1502 if (asoc
->ep
->rcvbuf_policy
)
1503 rx_count
= atomic_read(&asoc
->rmem_alloc
);
1505 rx_count
= atomic_read(&asoc
->base
.sk
->sk_rmem_alloc
);
1507 /* If we've reached or overflowed our receive buffer, announce
1508 * a 0 rwnd if rwnd would still be positive. Store the
1509 * the pottential pressure overflow so that the window can be restored
1510 * back to original value.
1512 if (rx_count
>= asoc
->base
.sk
->sk_rcvbuf
)
1515 if (asoc
->rwnd
>= len
) {
1518 asoc
->rwnd_press
+= asoc
->rwnd
;
1522 asoc
->rwnd_over
= len
- asoc
->rwnd
;
1525 SCTP_DEBUG_PRINTK("%s: asoc %p rwnd decreased by %d to (%u, %u, %u)\n",
1526 __func__
, asoc
, len
, asoc
->rwnd
,
1527 asoc
->rwnd_over
, asoc
->rwnd_press
);
1530 /* Build the bind address list for the association based on info from the
1531 * local endpoint and the remote peer.
1533 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association
*asoc
,
1534 sctp_scope_t scope
, gfp_t gfp
)
1538 /* Use scoping rules to determine the subset of addresses from
1541 flags
= (PF_INET6
== asoc
->base
.sk
->sk_family
) ? SCTP_ADDR6_ALLOWED
: 0;
1542 if (asoc
->peer
.ipv4_address
)
1543 flags
|= SCTP_ADDR4_PEERSUPP
;
1544 if (asoc
->peer
.ipv6_address
)
1545 flags
|= SCTP_ADDR6_PEERSUPP
;
1547 return sctp_bind_addr_copy(sock_net(asoc
->base
.sk
),
1548 &asoc
->base
.bind_addr
,
1549 &asoc
->ep
->base
.bind_addr
,
1553 /* Build the association's bind address list from the cookie. */
1554 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association
*asoc
,
1555 struct sctp_cookie
*cookie
,
1558 int var_size2
= ntohs(cookie
->peer_init
->chunk_hdr
.length
);
1559 int var_size3
= cookie
->raw_addr_list_len
;
1560 __u8
*raw
= (__u8
*)cookie
->peer_init
+ var_size2
;
1562 return sctp_raw_to_bind_addrs(&asoc
->base
.bind_addr
, raw
, var_size3
,
1563 asoc
->ep
->base
.bind_addr
.port
, gfp
);
1566 /* Lookup laddr in the bind address list of an association. */
1567 int sctp_assoc_lookup_laddr(struct sctp_association
*asoc
,
1568 const union sctp_addr
*laddr
)
1572 if ((asoc
->base
.bind_addr
.port
== ntohs(laddr
->v4
.sin_port
)) &&
1573 sctp_bind_addr_match(&asoc
->base
.bind_addr
, laddr
,
1574 sctp_sk(asoc
->base
.sk
)))
1580 /* Set an association id for a given association */
1581 int sctp_assoc_set_id(struct sctp_association
*asoc
, gfp_t gfp
)
1583 bool preload
= gfp
& __GFP_WAIT
;
1586 /* If the id is already assigned, keep it. */
1592 spin_lock_bh(&sctp_assocs_id_lock
);
1593 /* 0 is not a valid assoc_id, must be >= 1 */
1594 ret
= idr_alloc_cyclic(&sctp_assocs_id
, asoc
, 1, 0, GFP_NOWAIT
);
1595 spin_unlock_bh(&sctp_assocs_id_lock
);
1601 asoc
->assoc_id
= (sctp_assoc_t
)ret
;
1605 /* Free the ASCONF queue */
1606 static void sctp_assoc_free_asconf_queue(struct sctp_association
*asoc
)
1608 struct sctp_chunk
*asconf
;
1609 struct sctp_chunk
*tmp
;
1611 list_for_each_entry_safe(asconf
, tmp
, &asoc
->addip_chunk_list
, list
) {
1612 list_del_init(&asconf
->list
);
1613 sctp_chunk_free(asconf
);
1617 /* Free asconf_ack cache */
1618 static void sctp_assoc_free_asconf_acks(struct sctp_association
*asoc
)
1620 struct sctp_chunk
*ack
;
1621 struct sctp_chunk
*tmp
;
1623 list_for_each_entry_safe(ack
, tmp
, &asoc
->asconf_ack_list
,
1625 list_del_init(&ack
->transmitted_list
);
1626 sctp_chunk_free(ack
);
1630 /* Clean up the ASCONF_ACK queue */
1631 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association
*asoc
)
1633 struct sctp_chunk
*ack
;
1634 struct sctp_chunk
*tmp
;
1636 /* We can remove all the entries from the queue up to
1637 * the "Peer-Sequence-Number".
1639 list_for_each_entry_safe(ack
, tmp
, &asoc
->asconf_ack_list
,
1641 if (ack
->subh
.addip_hdr
->serial
==
1642 htonl(asoc
->peer
.addip_serial
))
1645 list_del_init(&ack
->transmitted_list
);
1646 sctp_chunk_free(ack
);
1650 /* Find the ASCONF_ACK whose serial number matches ASCONF */
1651 struct sctp_chunk
*sctp_assoc_lookup_asconf_ack(
1652 const struct sctp_association
*asoc
,
1655 struct sctp_chunk
*ack
;
1657 /* Walk through the list of cached ASCONF-ACKs and find the
1658 * ack chunk whose serial number matches that of the request.
1660 list_for_each_entry(ack
, &asoc
->asconf_ack_list
, transmitted_list
) {
1661 if (ack
->subh
.addip_hdr
->serial
== serial
) {
1662 sctp_chunk_hold(ack
);
1670 void sctp_asconf_queue_teardown(struct sctp_association
*asoc
)
1672 /* Free any cached ASCONF_ACK chunk. */
1673 sctp_assoc_free_asconf_acks(asoc
);
1675 /* Free the ASCONF queue. */
1676 sctp_assoc_free_asconf_queue(asoc
);
1678 /* Free any cached ASCONF chunk. */
1679 if (asoc
->addip_last_asconf
)
1680 sctp_chunk_free(asoc
->addip_last_asconf
);