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.
7 * This file is part of the SCTP kernel implementation
9 * This SCTP implementation is free software;
10 * you can redistribute it and/or modify it under the terms of
11 * the GNU General Public License as published by
12 * the Free Software Foundation; either version 2, or (at your option)
15 * This SCTP implementation is distributed in the hope that it
16 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
17 * ************************
18 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
19 * See the GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with GNU CC; see the file COPYING. If not, write to
23 * the Free Software Foundation, 59 Temple Place - Suite 330,
24 * Boston, MA 02111-1307, USA.
26 * Please send any bug reports or fixes you make to the
28 * lksctp developers <lksctp-developers@lists.sourceforge.net>
30 * Or submit a bug report through the following website:
31 * http://www.sf.net/projects/lksctp
33 * Written or modified by:
34 * Randall Stewart <randall@sctp.chicago.il.us>
35 * Ken Morneau <kmorneau@cisco.com>
36 * Qiaobing Xie <qxie1@email.mot.com>
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 * Dajiang Zhang <dajiang.zhang@nokia.com>
45 * Ardelle Fan <ardelle.fan@intel.com>
46 * Ryan Layer <rmlayer@us.ibm.com>
47 * Anup Pemmaiah <pemmaiah@cc.usu.edu>
48 * Kevin Gao <kevin.gao@intel.com>
50 * Any bugs reported given to us we will try to fix... any fixes shared will
51 * be incorporated into the next SCTP release.
54 #ifndef __sctp_structs_h__
55 #define __sctp_structs_h__
57 #include <linux/time.h> /* We get struct timespec. */
58 #include <linux/socket.h> /* linux/in.h needs this!! */
59 #include <linux/in.h> /* We get struct sockaddr_in. */
60 #include <linux/in6.h> /* We get struct in6_addr */
61 #include <linux/ipv6.h>
62 #include <asm/param.h> /* We get MAXHOSTNAMELEN. */
63 #include <linux/atomic.h> /* This gets us atomic counters. */
64 #include <linux/skbuff.h> /* We need sk_buff_head. */
65 #include <linux/workqueue.h> /* We need tq_struct. */
66 #include <linux/sctp.h> /* We need sctp* header structs. */
67 #include <net/sctp/auth.h> /* We need auth specific structs */
69 /* A convenience structure for handling sockaddr structures.
70 * We should wean ourselves off this.
73 struct sockaddr_in v4
;
74 struct sockaddr_in6 v6
;
78 /* Forward declarations for data structures. */
81 struct sctp_association
;
82 struct sctp_transport
;
87 struct sctp_bind_addr
;
89 struct sctp_ep_common
;
94 #include <net/sctp/tsnmap.h>
95 #include <net/sctp/ulpevent.h>
96 #include <net/sctp/ulpqueue.h>
98 /* Structures useful for managing bind/connect. */
100 struct sctp_bind_bucket
{
102 unsigned short fastreuse
;
103 struct hlist_node node
;
104 struct hlist_head owner
;
108 struct sctp_bind_hashbucket
{
110 struct hlist_head chain
;
113 /* Used for hashing all associations. */
114 struct sctp_hashbucket
{
116 struct hlist_head chain
;
117 } __attribute__((__aligned__(8)));
120 /* The SCTP globals structure. */
121 extern struct sctp_globals
{
122 /* RFC2960 Section 14. Suggested SCTP Protocol Parameter Values
124 * The following protocol parameters are RECOMMENDED:
126 * RTO.Initial - 3 seconds
128 * RTO.Max - 60 seconds
129 * RTO.Alpha - 1/8 (3 when converted to right shifts.)
130 * RTO.Beta - 1/4 (2 when converted to right shifts.)
132 unsigned int rto_initial
;
133 unsigned int rto_min
;
134 unsigned int rto_max
;
136 /* Note: rto_alpha and rto_beta are really defined as inverse
137 * powers of two to facilitate integer operations.
145 /* Whether Cookie Preservative is enabled(1) or not(0) */
146 int cookie_preserve_enable
;
148 /* Valid.Cookie.Life - 60 seconds */
149 unsigned int valid_cookie_life
;
151 /* Delayed SACK timeout 200ms default*/
152 unsigned int sack_timeout
;
154 /* HB.interval - 30 seconds */
155 unsigned int hb_interval
;
157 /* Association.Max.Retrans - 10 attempts
158 * Path.Max.Retrans - 5 attempts (per destination address)
159 * Max.Init.Retransmits - 8 attempts
161 int max_retrans_association
;
162 int max_retrans_path
;
163 int max_retrans_init
;
165 /* Potentially-Failed.Max.Retrans sysctl value
167 * http://tools.ietf.org/html/draft-nishida-tsvwg-sctp-failover-05
172 * Policy for preforming sctp/socket accounting
173 * 0 - do socket level accounting, all assocs share sk_sndbuf
174 * 1 - do sctp accounting, each asoc may use sk_sndbuf bytes
179 * Policy for preforming sctp/socket accounting
180 * 0 - do socket level accounting, all assocs share sk_rcvbuf
181 * 1 - do sctp accounting, each asoc may use sk_rcvbuf bytes
185 /* The following variables are implementation specific. */
187 /* Default initialization values to be applied to new associations. */
189 __u16 max_outstreams
;
191 /* This is a list of groups of functions for each address
192 * family that we support.
194 struct list_head address_families
;
196 /* This is the hash of all endpoints. */
198 struct sctp_hashbucket
*ep_hashtable
;
200 /* This is the hash of all associations. */
202 struct sctp_hashbucket
*assoc_hashtable
;
204 /* This is the sctp port control hash. */
206 struct sctp_bind_hashbucket
*port_hashtable
;
208 /* This is the global local address list.
209 * We actively maintain this complete list of addresses on
210 * the system by catching address add/delete events.
212 * It is a list of sctp_sockaddr_entry.
214 struct list_head local_addr_list
;
215 int default_auto_asconf
;
216 struct list_head addr_waitq
;
217 struct timer_list addr_wq_timer
;
218 struct list_head auto_asconf_splist
;
219 spinlock_t addr_wq_lock
;
221 /* Lock that protects the local_addr_list writers */
222 spinlock_t addr_list_lock
;
224 /* Flag to indicate if addip is enabled. */
226 int addip_noauth_enable
;
228 /* Flag to indicate if PR-SCTP is enabled. */
231 /* Flag to idicate if SCTP-AUTH is enabled */
235 * Policy to control SCTP IPv4 address scoping
236 * 0 - Disable IPv4 address scoping
237 * 1 - Enable IPv4 address scoping
238 * 2 - Selectively allow only IPv4 private addresses
239 * 3 - Selectively allow only IPv4 link local address
241 int ipv4_scope_policy
;
243 /* Flag to indicate whether computing and verifying checksum
245 bool checksum_disable
;
247 /* Threshold for rwnd update SACKS. Receive buffer shifted this many
248 * bits is an indicator of when to send and window update SACK.
250 int rwnd_update_shift
;
252 /* Threshold for autoclose timeout, in seconds. */
253 unsigned long max_autoclose
;
256 #define sctp_rto_initial (sctp_globals.rto_initial)
257 #define sctp_rto_min (sctp_globals.rto_min)
258 #define sctp_rto_max (sctp_globals.rto_max)
259 #define sctp_rto_alpha (sctp_globals.rto_alpha)
260 #define sctp_rto_beta (sctp_globals.rto_beta)
261 #define sctp_max_burst (sctp_globals.max_burst)
262 #define sctp_valid_cookie_life (sctp_globals.valid_cookie_life)
263 #define sctp_cookie_preserve_enable (sctp_globals.cookie_preserve_enable)
264 #define sctp_max_retrans_association (sctp_globals.max_retrans_association)
265 #define sctp_sndbuf_policy (sctp_globals.sndbuf_policy)
266 #define sctp_rcvbuf_policy (sctp_globals.rcvbuf_policy)
267 #define sctp_max_retrans_path (sctp_globals.max_retrans_path)
268 #define sctp_pf_retrans (sctp_globals.pf_retrans)
269 #define sctp_max_retrans_init (sctp_globals.max_retrans_init)
270 #define sctp_sack_timeout (sctp_globals.sack_timeout)
271 #define sctp_hb_interval (sctp_globals.hb_interval)
272 #define sctp_max_instreams (sctp_globals.max_instreams)
273 #define sctp_max_outstreams (sctp_globals.max_outstreams)
274 #define sctp_address_families (sctp_globals.address_families)
275 #define sctp_ep_hashsize (sctp_globals.ep_hashsize)
276 #define sctp_ep_hashtable (sctp_globals.ep_hashtable)
277 #define sctp_assoc_hashsize (sctp_globals.assoc_hashsize)
278 #define sctp_assoc_hashtable (sctp_globals.assoc_hashtable)
279 #define sctp_port_hashsize (sctp_globals.port_hashsize)
280 #define sctp_port_hashtable (sctp_globals.port_hashtable)
281 #define sctp_local_addr_list (sctp_globals.local_addr_list)
282 #define sctp_local_addr_lock (sctp_globals.addr_list_lock)
283 #define sctp_auto_asconf_splist (sctp_globals.auto_asconf_splist)
284 #define sctp_addr_waitq (sctp_globals.addr_waitq)
285 #define sctp_addr_wq_timer (sctp_globals.addr_wq_timer)
286 #define sctp_addr_wq_lock (sctp_globals.addr_wq_lock)
287 #define sctp_default_auto_asconf (sctp_globals.default_auto_asconf)
288 #define sctp_scope_policy (sctp_globals.ipv4_scope_policy)
289 #define sctp_addip_enable (sctp_globals.addip_enable)
290 #define sctp_addip_noauth (sctp_globals.addip_noauth_enable)
291 #define sctp_prsctp_enable (sctp_globals.prsctp_enable)
292 #define sctp_auth_enable (sctp_globals.auth_enable)
293 #define sctp_checksum_disable (sctp_globals.checksum_disable)
294 #define sctp_rwnd_upd_shift (sctp_globals.rwnd_update_shift)
295 #define sctp_max_autoclose (sctp_globals.max_autoclose)
297 /* SCTP Socket type: UDP or TCP style. */
300 SCTP_SOCKET_UDP_HIGH_BANDWIDTH
,
302 } sctp_socket_type_t
;
304 /* Per socket SCTP information. */
306 /* inet_sock has to be the first member of sctp_sock */
307 struct inet_sock inet
;
308 /* What kind of a socket is this? */
309 sctp_socket_type_t type
;
311 /* PF_ family specific functions. */
314 /* Access to HMAC transform. */
315 struct crypto_hash
*hmac
;
317 /* What is our base endpointer? */
318 struct sctp_endpoint
*ep
;
320 struct sctp_bind_bucket
*bind_hash
;
321 /* Various Socket Options. */
322 __u16 default_stream
;
325 __u32 default_context
;
326 __u32 default_timetolive
;
327 __u32 default_rcv_context
;
330 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
331 * the destination address every heartbeat interval. This value
332 * will be inherited by all new associations.
336 /* This is the max_retrans value for new associations. */
339 /* The initial Path MTU to use for new associations. */
342 /* The default SACK delay timeout for new associations. */
346 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
349 struct sctp_initmsg initmsg
;
350 struct sctp_rtoinfo rtoinfo
;
351 struct sctp_paddrparams paddrparam
;
352 struct sctp_event_subscribe subscribe
;
353 struct sctp_assocparams assocparams
;
357 __u8 disable_fragments
;
359 __u8 frag_interleave
;
360 __u32 adaptation_ind
;
364 /* Receive to here while partial delivery is in effect. */
365 struct sk_buff_head pd_lobby
;
366 struct list_head auto_asconf_list
;
370 static inline struct sctp_sock
*sctp_sk(const struct sock
*sk
)
372 return (struct sctp_sock
*)sk
;
375 static inline struct sock
*sctp_opt2sk(const struct sctp_sock
*sp
)
377 return (struct sock
*)sp
;
380 #if IS_ENABLED(CONFIG_IPV6)
382 struct sctp_sock sctp
;
383 struct ipv6_pinfo inet6
;
385 #endif /* CONFIG_IPV6 */
388 /* This is our APPLICATION-SPECIFIC state cookie.
389 * THIS IS NOT DICTATED BY THE SPECIFICATION.
391 /* These are the parts of an association which we send in the cookie.
392 * Most of these are straight out of:
393 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
399 /* My : Tag expected in every inbound packet and sent
400 * Verification: in the INIT or INIT ACK chunk.
405 /* Peer's : Tag expected in every outbound packet except
406 * Verification: in the INIT chunk.
411 /* The rest of these are not from the spec, but really need to
415 /* My Tie Tag : Assist in discovering a restarting association. */
418 /* Peer's Tie Tag: Assist in discovering a restarting association. */
421 /* When does this cookie expire? */
422 struct timeval expiration
;
424 /* Number of inbound/outbound streams which are set
425 * and negotiated during the INIT process.
427 __u16 sinit_num_ostreams
;
428 __u16 sinit_max_instreams
;
430 /* This is the first sequence number I used. */
433 /* This holds the originating address of the INIT packet. */
434 union sctp_addr peer_addr
;
437 * Include the source port of the INIT-ACK
443 /* Padding for future use */
446 __u32 adaptation_ind
;
448 __u8 auth_random
[sizeof(sctp_paramhdr_t
) + SCTP_AUTH_RANDOM_LENGTH
];
449 __u8 auth_hmacs
[SCTP_AUTH_NUM_HMACS
* sizeof(__u16
) + 2];
450 __u8 auth_chunks
[sizeof(sctp_paramhdr_t
) + SCTP_AUTH_MAX_CHUNKS
];
452 /* This is a shim for my peer's INIT packet, followed by
453 * a copy of the raw address list of the association.
454 * The length of the raw address list is saved in the
455 * raw_addr_list_len field, which will be used at the time when
456 * the association TCB is re-constructed from the cookie.
458 __u32 raw_addr_list_len
;
459 struct sctp_init_chunk peer_init
[0];
463 /* The format of our cookie that we send to our peer. */
464 struct sctp_signed_cookie
{
465 __u8 signature
[SCTP_SECRET_SIZE
];
466 __u32 __pad
; /* force sctp_cookie alignment to 64 bits */
467 struct sctp_cookie c
;
470 /* This is another convenience type to allocate memory for address
471 * params for the maximum size and pass such structures around
474 union sctp_addr_param
{
475 struct sctp_paramhdr p
;
476 struct sctp_ipv4addr_param v4
;
477 struct sctp_ipv6addr_param v6
;
480 /* A convenience type to allow walking through the various
481 * parameters and avoid casting all over the place.
485 struct sctp_paramhdr
*p
;
486 struct sctp_cookie_preserve_param
*life
;
487 struct sctp_hostname_param
*dns
;
488 struct sctp_cookie_param
*cookie
;
489 struct sctp_supported_addrs_param
*sat
;
490 struct sctp_ipv4addr_param
*v4
;
491 struct sctp_ipv6addr_param
*v6
;
492 union sctp_addr_param
*addr
;
493 struct sctp_adaptation_ind_param
*aind
;
494 struct sctp_supported_ext_param
*ext
;
495 struct sctp_random_param
*random
;
496 struct sctp_chunks_param
*chunks
;
497 struct sctp_hmac_algo_param
*hmac_algo
;
498 struct sctp_addip_param
*addip
;
501 /* RFC 2960. Section 3.3.5 Heartbeat.
502 * Heartbeat Information: variable length
503 * The Sender-specific Heartbeat Info field should normally include
504 * information about the sender's current time when this HEARTBEAT
505 * chunk is sent and the destination transport address to which this
506 * HEARTBEAT is sent (see Section 8.3).
508 typedef struct sctp_sender_hb_info
{
509 struct sctp_paramhdr param_hdr
;
510 union sctp_addr daddr
;
511 unsigned long sent_at
;
513 } __packed sctp_sender_hb_info_t
;
516 * RFC 2960 1.3.2 Sequenced Delivery within Streams
518 * The term "stream" is used in SCTP to refer to a sequence of user
519 * messages that are to be delivered to the upper-layer protocol in
520 * order with respect to other messages within the same stream. This is
521 * in contrast to its usage in TCP, where it refers to a sequence of
522 * bytes (in this document a byte is assumed to be eight bits).
525 * This is the structure we use to track both our outbound and inbound
526 * SSN, or Stream Sequence Numbers.
535 struct sctp_stream in
;
536 struct sctp_stream out
;
540 struct sctp_ssnmap
*sctp_ssnmap_new(__u16 in
, __u16 out
,
542 void sctp_ssnmap_free(struct sctp_ssnmap
*map
);
543 void sctp_ssnmap_clear(struct sctp_ssnmap
*map
);
545 /* What is the current SSN number for this stream? */
546 static inline __u16
sctp_ssn_peek(struct sctp_stream
*stream
, __u16 id
)
548 return stream
->ssn
[id
];
551 /* Return the next SSN number for this stream. */
552 static inline __u16
sctp_ssn_next(struct sctp_stream
*stream
, __u16 id
)
554 return stream
->ssn
[id
]++;
557 /* Skip over this ssn and all below. */
558 static inline void sctp_ssn_skip(struct sctp_stream
*stream
, __u16 id
,
561 stream
->ssn
[id
] = ssn
+1;
565 * Pointers to address related SCTP functions.
566 * (i.e. things that depend on the address family.)
569 int (*sctp_xmit
) (struct sk_buff
*skb
,
570 struct sctp_transport
*);
571 int (*setsockopt
) (struct sock
*sk
,
575 unsigned int optlen
);
576 int (*getsockopt
) (struct sock
*sk
,
581 int (*compat_setsockopt
) (struct sock
*sk
,
585 unsigned int optlen
);
586 int (*compat_getsockopt
) (struct sock
*sk
,
591 void (*get_dst
) (struct sctp_transport
*t
,
592 union sctp_addr
*saddr
,
595 void (*get_saddr
) (struct sctp_sock
*sk
,
596 struct sctp_transport
*t
,
598 void (*copy_addrlist
) (struct list_head
*,
599 struct net_device
*);
600 int (*cmp_addr
) (const union sctp_addr
*addr1
,
601 const union sctp_addr
*addr2
);
602 void (*addr_copy
) (union sctp_addr
*dst
,
603 union sctp_addr
*src
);
604 void (*from_skb
) (union sctp_addr
*,
607 void (*from_sk
) (union sctp_addr
*,
609 void (*to_sk_saddr
) (union sctp_addr
*,
611 void (*to_sk_daddr
) (union sctp_addr
*,
613 void (*from_addr_param
) (union sctp_addr
*,
614 union sctp_addr_param
*,
615 __be16 port
, int iif
);
616 int (*to_addr_param
) (const union sctp_addr
*,
617 union sctp_addr_param
*);
618 int (*addr_valid
) (union sctp_addr
*,
620 const struct sk_buff
*);
621 sctp_scope_t (*scope
) (union sctp_addr
*);
622 void (*inaddr_any
) (union sctp_addr
*, __be16
);
623 int (*is_any
) (const union sctp_addr
*);
624 int (*available
) (union sctp_addr
*,
626 int (*skb_iif
) (const struct sk_buff
*sk
);
627 int (*is_ce
) (const struct sk_buff
*sk
);
628 void (*seq_dump_addr
)(struct seq_file
*seq
,
629 union sctp_addr
*addr
);
630 void (*ecn_capable
)(struct sock
*sk
);
631 __u16 net_header_len
;
633 sa_family_t sa_family
;
634 struct list_head list
;
637 struct sctp_af
*sctp_get_af_specific(sa_family_t
);
638 int sctp_register_af(struct sctp_af
*);
640 /* Protocol family functions. */
642 void (*event_msgname
)(struct sctp_ulpevent
*, char *, int *);
643 void (*skb_msgname
) (struct sk_buff
*, char *, int *);
644 int (*af_supported
) (sa_family_t
, struct sctp_sock
*);
645 int (*cmp_addr
) (const union sctp_addr
*,
646 const union sctp_addr
*,
648 int (*bind_verify
) (struct sctp_sock
*, union sctp_addr
*);
649 int (*send_verify
) (struct sctp_sock
*, union sctp_addr
*);
650 int (*supported_addrs
)(const struct sctp_sock
*, __be16
*);
651 struct sock
*(*create_accept_sk
) (struct sock
*sk
,
652 struct sctp_association
*asoc
);
653 void (*addr_v4map
) (struct sctp_sock
*, union sctp_addr
*);
658 /* Structure to track chunk fragments that have been acked, but peer
659 * fragments of the same message have not.
661 struct sctp_datamsg
{
662 /* Chunks waiting to be submitted to lower layer. */
663 struct list_head chunks
;
664 /* Reference counting. */
666 /* When is this message no longer interesting to the peer? */
667 unsigned long expires_at
;
668 /* Did the messenge fail to send? */
671 can_abandon
:1, /* can chunks from this message can be abandoned. */
672 can_delay
; /* should this message be Nagle delayed */
675 struct sctp_datamsg
*sctp_datamsg_from_user(struct sctp_association
*,
676 struct sctp_sndrcvinfo
*,
677 struct msghdr
*, int len
);
678 void sctp_datamsg_free(struct sctp_datamsg
*);
679 void sctp_datamsg_put(struct sctp_datamsg
*);
680 void sctp_chunk_fail(struct sctp_chunk
*, int error
);
681 int sctp_chunk_abandoned(struct sctp_chunk
*);
683 /* RFC2960 1.4 Key Terms
685 * o Chunk: A unit of information within an SCTP packet, consisting of
686 * a chunk header and chunk-specific content.
688 * As a matter of convenience, we remember the SCTP common header for
689 * each chunk as well as a few other header pointers...
692 struct list_head list
;
696 /* This is our link to the per-transport transmitted list. */
697 struct list_head transmitted_list
;
699 /* This field is used by chunks that hold fragmented data.
700 * For the first fragment this is the list that holds the rest of
701 * fragments. For the remaining fragments, this is the link to the
702 * frag_list maintained in the first fragment.
704 struct list_head frag_list
;
706 /* This points to the sk_buff containing the actual data. */
709 /* These are the SCTP headers by reverse order in a packet.
710 * Note that some of these may happen more than once. In that
711 * case, we point at the "current" one, whatever that means
712 * for that level of header.
715 /* We point this at the FIRST TLV parameter to chunk_hdr. */
716 union sctp_params param_hdr
;
719 struct sctp_datahdr
*data_hdr
;
720 struct sctp_inithdr
*init_hdr
;
721 struct sctp_sackhdr
*sack_hdr
;
722 struct sctp_heartbeathdr
*hb_hdr
;
723 struct sctp_sender_hb_info
*hbs_hdr
;
724 struct sctp_shutdownhdr
*shutdown_hdr
;
725 struct sctp_signed_cookie
*cookie_hdr
;
726 struct sctp_ecnehdr
*ecne_hdr
;
727 struct sctp_cwrhdr
*ecn_cwr_hdr
;
728 struct sctp_errhdr
*err_hdr
;
729 struct sctp_addiphdr
*addip_hdr
;
730 struct sctp_fwdtsn_hdr
*fwdtsn_hdr
;
731 struct sctp_authhdr
*auth_hdr
;
736 struct sctp_chunkhdr
*chunk_hdr
;
737 struct sctphdr
*sctp_hdr
;
739 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
740 struct sctp_sndrcvinfo sinfo
;
742 /* Which association does this belong to? */
743 struct sctp_association
*asoc
;
745 /* What endpoint received this chunk? */
746 struct sctp_ep_common
*rcvr
;
748 /* We fill this in if we are calculating RTT. */
749 unsigned long sent_at
;
751 /* What is the origin IP address for this chunk? */
752 union sctp_addr source
;
753 /* Destination address for this chunk. */
754 union sctp_addr dest
;
756 /* For outbound message, track all fragments for SEND_FAILED. */
757 struct sctp_datamsg
*msg
;
759 /* For an inbound chunk, this tells us where it came from.
760 * For an outbound chunk, it tells us where we'd like it to
761 * go. It is NULL if we have no preference.
763 struct sctp_transport
*transport
;
765 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO
766 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
767 * spec violates the principle premis that all chunks are processed
770 struct sk_buff
*auth_chunk
;
772 #define SCTP_CAN_FRTX 0x0
773 #define SCTP_NEED_FRTX 0x1
774 #define SCTP_DONT_FRTX 0x2
775 __u16 rtt_in_progress
:1, /* This chunk used for RTT calc? */
776 has_tsn
:1, /* Does this chunk have a TSN yet? */
777 has_ssn
:1, /* Does this chunk have a SSN yet? */
778 singleton
:1, /* Only chunk in the packet? */
779 end_of_packet
:1, /* Last chunk in the packet? */
780 ecn_ce_done
:1, /* Have we processed the ECN CE bit? */
781 pdiscard
:1, /* Discard the whole packet now? */
782 tsn_gap_acked
:1, /* Is this chunk acked by a GAP ACK? */
783 data_accepted
:1, /* At least 1 chunk accepted */
784 auth
:1, /* IN: was auth'ed | OUT: needs auth */
785 has_asconf
:1, /* IN: have seen an asconf before */
786 tsn_missing_report
:2, /* Data chunk missing counter. */
787 fast_retransmit
:2; /* Is this chunk fast retransmitted? */
790 void sctp_chunk_hold(struct sctp_chunk
*);
791 void sctp_chunk_put(struct sctp_chunk
*);
792 int sctp_user_addto_chunk(struct sctp_chunk
*chunk
, int off
, int len
,
794 void sctp_chunk_free(struct sctp_chunk
*);
795 void *sctp_addto_chunk(struct sctp_chunk
*, int len
, const void *data
);
796 void *sctp_addto_chunk_fixed(struct sctp_chunk
*, int len
, const void *data
);
797 struct sctp_chunk
*sctp_chunkify(struct sk_buff
*,
798 const struct sctp_association
*,
800 void sctp_init_addrs(struct sctp_chunk
*, union sctp_addr
*,
802 const union sctp_addr
*sctp_source(const struct sctp_chunk
*chunk
);
805 SCTP_ADDR_NEW
, /* new address added to assoc/ep */
806 SCTP_ADDR_SRC
, /* address can be used as source */
807 SCTP_ADDR_DEL
, /* address about to be deleted */
810 /* This is a structure for holding either an IPv6 or an IPv4 address. */
811 struct sctp_sockaddr_entry
{
812 struct list_head list
;
819 #define SCTP_ADDRESS_TICK_DELAY 500
821 typedef struct sctp_chunk
*(sctp_packet_phandler_t
)(struct sctp_association
*);
823 /* This structure holds lists of chunks as we are assembling for
827 /* These are the SCTP header values (host order) for the packet. */
829 __u16 destination_port
;
832 /* This contains the payload chunks. */
833 struct list_head chunk_list
;
835 /* This is the overhead of the sctp and ip headers. */
837 /* This is the total size of all chunks INCLUDING padding. */
840 /* The packet is destined for this transport address.
841 * The function we finally use to pass down to the next lower
842 * layer lives in the transport structure.
844 struct sctp_transport
*transport
;
846 /* pointer to the auth chunk for this packet */
847 struct sctp_chunk
*auth
;
849 u8 has_cookie_echo
:1, /* This packet contains a COOKIE-ECHO chunk. */
850 has_sack
:1, /* This packet contains a SACK chunk. */
851 has_auth
:1, /* This packet contains an AUTH chunk */
852 has_data
:1, /* This packet contains at least 1 DATA chunk */
853 ipfragok
:1, /* So let ip fragment this packet */
854 malloced
:1; /* Is it malloced? */
857 struct sctp_packet
*sctp_packet_init(struct sctp_packet
*,
858 struct sctp_transport
*,
859 __u16 sport
, __u16 dport
);
860 struct sctp_packet
*sctp_packet_config(struct sctp_packet
*, __u32 vtag
, int);
861 sctp_xmit_t
sctp_packet_transmit_chunk(struct sctp_packet
*,
862 struct sctp_chunk
*, int);
863 sctp_xmit_t
sctp_packet_append_chunk(struct sctp_packet
*,
864 struct sctp_chunk
*);
865 int sctp_packet_transmit(struct sctp_packet
*);
866 void sctp_packet_free(struct sctp_packet
*);
868 static inline int sctp_packet_empty(struct sctp_packet
*packet
)
870 return packet
->size
== packet
->overhead
;
873 /* This represents a remote transport address.
874 * For local transport addresses, we just use union sctp_addr.
876 * RFC2960 Section 1.4 Key Terms
878 * o Transport address: A Transport Address is traditionally defined
879 * by Network Layer address, Transport Layer protocol and Transport
880 * Layer port number. In the case of SCTP running over IP, a
881 * transport address is defined by the combination of an IP address
882 * and an SCTP port number (where SCTP is the Transport protocol).
884 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
886 * o The sender keeps a separate congestion control parameter set for
887 * each of the destination addresses it can send to (not each
888 * source-destination pair but for each destination). The parameters
889 * should decay if the address is not used for a long enough time
893 struct sctp_transport
{
894 /* A list of transports. */
895 struct list_head transports
;
897 /* Reference counting. */
900 /* RTO-Pending : A flag used to track if one of the DATA
901 * chunks sent to this address is currently being
902 * used to compute a RTT. If this flag is 0,
903 * the next DATA chunk sent to this destination
904 * should be used to compute a RTT and this flag
905 * should be set. Every time the RTT
906 * calculation completes (i.e. the DATA chunk
907 * is SACK'd) clear this flag.
912 * hb_sent : a flag that signals that we have a pending
917 /* Is the Path MTU update pending on this tranport */
920 /* Is this structure kfree()able? */
923 /* Has this transport moved the ctsn since we last sacked */
924 __u32 sack_generation
;
928 /* This is the peer's IP address and port. */
929 union sctp_addr ipaddr
;
931 /* These are the functions we call to handle LLP stuff. */
932 struct sctp_af
*af_specific
;
934 /* Which association do we belong to? */
935 struct sctp_association
*asoc
;
939 * 12.3 Per Transport Address Data
941 * For each destination transport address in the peer's
942 * address list derived from the INIT or INIT ACK chunk, a
943 * number of data elements needs to be maintained including:
945 /* RTO : The current retransmission timeout value. */
948 __u32 rtt
; /* This is the most recent RTT. */
950 /* RTTVAR : The current RTT variation. */
953 /* SRTT : The current smoothed round trip time. */
957 * These are the congestion stats.
959 /* cwnd : The current congestion window. */
960 __u32 cwnd
; /* This is the actual cwnd. */
962 /* ssthresh : The current slow start threshold value. */
965 /* partial : The tracking method for increase of cwnd when in
966 * bytes acked : congestion avoidance mode (see Section 6.2.2)
968 __u32 partial_bytes_acked
;
970 /* Data that has been sent, but not acknowledged. */
973 __u32 burst_limited
; /* Holds old cwnd when max.burst is applied */
976 struct dst_entry
*dst
;
977 /* Source address. */
978 union sctp_addr saddr
;
980 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
981 * the destination address every heartbeat interval.
983 unsigned long hbinterval
;
985 /* SACK delay timeout */
986 unsigned long sackdelay
;
989 /* When was the last time (in jiffies) that we heard from this
990 * transport? We use this to pick new active and retran paths.
992 unsigned long last_time_heard
;
994 /* Last time(in jiffies) when cwnd is reduced due to the congestion
995 * indication based on ECNE chunk.
997 unsigned long last_time_ecne_reduced
;
999 /* This is the max_retrans value for the transport and will
1000 * be initialized from the assocs value. This can be changed
1001 * using the SCTP_SET_PEER_ADDR_PARAMS socket option.
1005 /* This is the partially failed retrans value for the transport
1006 * and will be initialized from the assocs value. This can be changed
1007 * using the SCTP_PEER_ADDR_THLDS socket option
1010 /* PMTU : The current known path MTU. */
1013 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1016 /* The number of times INIT has been sent on this transport. */
1017 int init_sent_count
;
1019 /* state : The current state of this destination,
1020 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
1024 /* These are the error stats for this destination. */
1026 /* Error count : The current error count for this destination. */
1027 unsigned short error_count
;
1029 /* Per : A timer used by each destination.
1033 * [Everywhere else in the text this is called T3-rtx. -ed]
1035 struct timer_list T3_rtx_timer
;
1037 /* Heartbeat timer is per destination. */
1038 struct timer_list hb_timer
;
1040 /* Timer to handle ICMP proto unreachable envets */
1041 struct timer_list proto_unreach_timer
;
1043 /* Since we're using per-destination retransmission timers
1044 * (see above), we're also using per-destination "transmitted"
1045 * queues. This probably ought to be a private struct
1046 * accessible only within the outqueue, but it's not, yet.
1048 struct list_head transmitted
;
1050 /* We build bundle-able packets for this transport here. */
1051 struct sctp_packet packet
;
1053 /* This is the list of transports that have chunks to send. */
1054 struct list_head send_ready
;
1056 /* State information saved for SFR_CACC algorithm. The key
1057 * idea in SFR_CACC is to maintain state at the sender on a
1058 * per-destination basis when a changeover happens.
1059 * char changeover_active;
1060 * char cycling_changeover;
1061 * __u32 next_tsn_at_change;
1062 * char cacc_saw_newack;
1065 /* An unsigned integer, which stores the next TSN to be
1066 * used by the sender, at the moment of changeover.
1068 __u32 next_tsn_at_change
;
1070 /* A flag which indicates the occurrence of a changeover */
1071 char changeover_active
;
1073 /* A flag which indicates whether the change of primary is
1074 * the first switch to this destination address during an
1077 char cycling_changeover
;
1079 /* A temporary flag, which is used during the processing of
1080 * a SACK to estimate the causative TSN(s)'s group.
1082 char cacc_saw_newack
;
1085 /* 64-bit random number sent with heartbeat. */
1089 struct sctp_transport
*sctp_transport_new(const union sctp_addr
*,
1091 void sctp_transport_set_owner(struct sctp_transport
*,
1092 struct sctp_association
*);
1093 void sctp_transport_route(struct sctp_transport
*, union sctp_addr
*,
1094 struct sctp_sock
*);
1095 void sctp_transport_pmtu(struct sctp_transport
*, struct sock
*sk
);
1096 void sctp_transport_free(struct sctp_transport
*);
1097 void sctp_transport_reset_timers(struct sctp_transport
*);
1098 void sctp_transport_hold(struct sctp_transport
*);
1099 void sctp_transport_put(struct sctp_transport
*);
1100 void sctp_transport_update_rto(struct sctp_transport
*, __u32
);
1101 void sctp_transport_raise_cwnd(struct sctp_transport
*, __u32
, __u32
);
1102 void sctp_transport_lower_cwnd(struct sctp_transport
*, sctp_lower_cwnd_t
);
1103 void sctp_transport_burst_limited(struct sctp_transport
*);
1104 void sctp_transport_burst_reset(struct sctp_transport
*);
1105 unsigned long sctp_transport_timeout(struct sctp_transport
*);
1106 void sctp_transport_reset(struct sctp_transport
*);
1107 void sctp_transport_update_pmtu(struct sock
*, struct sctp_transport
*, u32
);
1108 void sctp_transport_immediate_rtx(struct sctp_transport
*);
1111 /* This is the structure we use to queue packets as they come into
1112 * SCTP. We write packets to it and read chunks from it.
1115 /* This is actually a queue of sctp_chunk each
1116 * containing a partially decoded packet.
1118 struct list_head in_chunk_list
;
1119 /* This is the packet which is currently off the in queue and is
1120 * being worked on through the inbound chunk processing.
1122 struct sctp_chunk
*in_progress
;
1124 /* This is the delayed task to finish delivering inbound
1127 struct work_struct immediate
;
1129 int malloced
; /* Is this structure kfree()able? */
1132 void sctp_inq_init(struct sctp_inq
*);
1133 void sctp_inq_free(struct sctp_inq
*);
1134 void sctp_inq_push(struct sctp_inq
*, struct sctp_chunk
*packet
);
1135 struct sctp_chunk
*sctp_inq_pop(struct sctp_inq
*);
1136 struct sctp_chunkhdr
*sctp_inq_peek(struct sctp_inq
*);
1137 void sctp_inq_set_th_handler(struct sctp_inq
*, work_func_t
);
1139 /* This is the structure we use to hold outbound chunks. You push
1140 * chunks in and they automatically pop out the other end as bundled
1141 * packets (it calls (*output_handler)()).
1143 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1144 * and 8.2 of the v13 draft.
1146 * It handles retransmissions. The connection to the timeout portion
1147 * of the state machine is through sctp_..._timeout() and timeout_handler.
1149 * If you feed it SACKs, it will eat them.
1151 * If you give it big chunks, it will fragment them.
1153 * It assigns TSN's to data chunks. This happens at the last possible
1154 * instant before transmission.
1156 * When free()'d, it empties itself out via output_handler().
1159 struct sctp_association
*asoc
;
1161 /* Data pending that has never been transmitted. */
1162 struct list_head out_chunk_list
;
1164 unsigned int out_qlen
; /* Total length of queued data chunks. */
1166 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1169 /* These are control chunks we want to send. */
1170 struct list_head control_chunk_list
;
1172 /* These are chunks that have been sacked but are above the
1173 * CTSN, or cumulative tsn ack point.
1175 struct list_head sacked
;
1177 /* Put chunks on this list to schedule them for
1180 struct list_head retransmit
;
1182 /* Put chunks on this list to save them for FWD TSN processing as
1183 * they were abandoned.
1185 struct list_head abandoned
;
1187 /* How many unackd bytes do we have in-flight? */
1188 __u32 outstanding_bytes
;
1190 /* Are we doing fast-rtx on this queue */
1196 /* Is this structure empty? */
1199 /* Are we kfree()able? */
1203 void sctp_outq_init(struct sctp_association
*, struct sctp_outq
*);
1204 void sctp_outq_teardown(struct sctp_outq
*);
1205 void sctp_outq_free(struct sctp_outq
*);
1206 int sctp_outq_tail(struct sctp_outq
*, struct sctp_chunk
*chunk
);
1207 int sctp_outq_sack(struct sctp_outq
*, struct sctp_sackhdr
*);
1208 int sctp_outq_is_empty(const struct sctp_outq
*);
1209 void sctp_outq_restart(struct sctp_outq
*);
1211 void sctp_retransmit(struct sctp_outq
*, struct sctp_transport
*,
1212 sctp_retransmit_reason_t
);
1213 void sctp_retransmit_mark(struct sctp_outq
*, struct sctp_transport
*, __u8
);
1214 int sctp_outq_uncork(struct sctp_outq
*);
1215 /* Uncork and flush an outqueue. */
1216 static inline void sctp_outq_cork(struct sctp_outq
*q
)
1221 /* These bind address data fields common between endpoints and associations */
1222 struct sctp_bind_addr
{
1224 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1226 * SCTP Port: The local SCTP port number the endpoint is
1231 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1233 * Address List: The list of IP addresses that this instance
1234 * has bound. This information is passed to one's
1235 * peer(s) in INIT and INIT ACK chunks.
1237 struct list_head address_list
;
1239 int malloced
; /* Are we kfree()able? */
1242 void sctp_bind_addr_init(struct sctp_bind_addr
*, __u16 port
);
1243 void sctp_bind_addr_free(struct sctp_bind_addr
*);
1244 int sctp_bind_addr_copy(struct sctp_bind_addr
*dest
,
1245 const struct sctp_bind_addr
*src
,
1246 sctp_scope_t scope
, gfp_t gfp
,
1248 int sctp_bind_addr_dup(struct sctp_bind_addr
*dest
,
1249 const struct sctp_bind_addr
*src
,
1251 int sctp_add_bind_addr(struct sctp_bind_addr
*, union sctp_addr
*,
1252 __u8 addr_state
, gfp_t gfp
);
1253 int sctp_del_bind_addr(struct sctp_bind_addr
*, union sctp_addr
*);
1254 int sctp_bind_addr_match(struct sctp_bind_addr
*, const union sctp_addr
*,
1255 struct sctp_sock
*);
1256 int sctp_bind_addr_conflict(struct sctp_bind_addr
*, const union sctp_addr
*,
1257 struct sctp_sock
*, struct sctp_sock
*);
1258 int sctp_bind_addr_state(const struct sctp_bind_addr
*bp
,
1259 const union sctp_addr
*addr
);
1260 union sctp_addr
*sctp_find_unmatch_addr(struct sctp_bind_addr
*bp
,
1261 const union sctp_addr
*addrs
,
1263 struct sctp_sock
*opt
);
1264 union sctp_params
sctp_bind_addrs_to_raw(const struct sctp_bind_addr
*bp
,
1267 int sctp_raw_to_bind_addrs(struct sctp_bind_addr
*bp
, __u8
*raw
, int len
,
1268 __u16 port
, gfp_t gfp
);
1270 sctp_scope_t
sctp_scope(const union sctp_addr
*);
1271 int sctp_in_scope(const union sctp_addr
*addr
, const sctp_scope_t scope
);
1272 int sctp_is_any(struct sock
*sk
, const union sctp_addr
*addr
);
1273 int sctp_addr_is_valid(const union sctp_addr
*addr
);
1274 int sctp_is_ep_boundall(struct sock
*sk
);
1277 /* What type of endpoint? */
1279 SCTP_EP_TYPE_SOCKET
,
1280 SCTP_EP_TYPE_ASSOCIATION
,
1281 } sctp_endpoint_type_t
;
1284 * A common base class to bridge the implmentation view of a
1285 * socket (usually listening) endpoint versus an association's
1287 * This common structure is useful for several purposes:
1288 * 1) Common interface for lookup routines.
1289 * a) Subfunctions work for either endpoint or association
1290 * b) Single interface to lookup allows hiding the lookup lock rather
1291 * than acquiring it externally.
1292 * 2) Common interface for the inbound chunk handling/state machine.
1293 * 3) Common object handling routines for reference counting, etc.
1294 * 4) Disentangle association lookup from endpoint lookup, where we
1295 * do not have to find our endpoint to find our association.
1299 struct sctp_ep_common
{
1300 /* Fields to help us manage our entries in the hash tables. */
1301 struct hlist_node node
;
1304 /* Runtime type information. What kind of endpoint is this? */
1305 sctp_endpoint_type_t type
;
1307 /* Some fields to help us manage this object.
1308 * refcnt - Reference count access to this object.
1309 * dead - Do not attempt to use this object.
1310 * malloced - Do we need to kfree this object?
1316 /* What socket does this endpoint belong to? */
1319 /* This is where we receive inbound chunks. */
1320 struct sctp_inq inqueue
;
1322 /* This substructure includes the defining parameters of the
1324 * bind_addr.port is our shared port number.
1325 * bind_addr.address_list is our set of local IP addresses.
1327 struct sctp_bind_addr bind_addr
;
1331 /* RFC Section 1.4 Key Terms
1333 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1334 * multi-homed host, an SCTP endpoint is represented to its peers as a
1335 * combination of a set of eligible destination transport addresses to
1336 * which SCTP packets can be sent and a set of eligible source
1337 * transport addresses from which SCTP packets can be received.
1338 * All transport addresses used by an SCTP endpoint must use the
1339 * same port number, but can use multiple IP addresses. A transport
1340 * address used by an SCTP endpoint must not be used by another
1341 * SCTP endpoint. In other words, a transport address is unique
1342 * to an SCTP endpoint.
1344 * From an implementation perspective, each socket has one of these.
1345 * A TCP-style socket will have exactly one association on one of
1346 * these. An UDP-style socket will have multiple associations hanging
1350 struct sctp_endpoint
{
1351 /* Common substructure for endpoint and association. */
1352 struct sctp_ep_common base
;
1354 /* Associations: A list of current associations and mappings
1355 * to the data consumers for each association. This
1356 * may be in the form of a hash table or other
1357 * implementation dependent structure. The data
1358 * consumers may be process identification
1359 * information such as file descriptors, named pipe
1360 * pointer, or table pointers dependent on how SCTP
1363 /* This is really a list of struct sctp_association entries. */
1364 struct list_head asocs
;
1366 /* Secret Key: A secret key used by this endpoint to compute
1367 * the MAC. This SHOULD be a cryptographic quality
1368 * random number with a sufficient length.
1369 * Discussion in [RFC1750] can be helpful in
1370 * selection of the key.
1372 __u8 secret_key
[SCTP_HOW_MANY_SECRETS
][SCTP_SECRET_SIZE
];
1377 /* digest: This is a digest of the sctp cookie. This field is
1378 * only used on the receive path when we try to validate
1379 * that the cookie has not been tampered with. We put
1380 * this here so we pre-allocate this once and can re-use
1385 /* sendbuf acct. policy. */
1386 __u32 sndbuf_policy
;
1388 /* rcvbuf acct. policy. */
1389 __u32 rcvbuf_policy
;
1391 /* SCTP AUTH: array of the HMACs that will be allocated
1392 * we need this per association so that we don't serialize
1394 struct crypto_hash
**auth_hmacs
;
1396 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1397 struct sctp_hmac_algo_param
*auth_hmacs_list
;
1399 /* SCTP-AUTH: chunks to authenticate encoded into parameter */
1400 struct sctp_chunks_param
*auth_chunk_list
;
1402 /* SCTP-AUTH: endpoint shared keys */
1403 struct list_head endpoint_shared_keys
;
1404 __u16 active_key_id
;
1407 /* Recover the outter endpoint structure. */
1408 static inline struct sctp_endpoint
*sctp_ep(struct sctp_ep_common
*base
)
1410 struct sctp_endpoint
*ep
;
1412 ep
= container_of(base
, struct sctp_endpoint
, base
);
1416 /* These are function signatures for manipulating endpoints. */
1417 struct sctp_endpoint
*sctp_endpoint_new(struct sock
*, gfp_t
);
1418 void sctp_endpoint_free(struct sctp_endpoint
*);
1419 void sctp_endpoint_put(struct sctp_endpoint
*);
1420 void sctp_endpoint_hold(struct sctp_endpoint
*);
1421 void sctp_endpoint_add_asoc(struct sctp_endpoint
*, struct sctp_association
*);
1422 struct sctp_association
*sctp_endpoint_lookup_assoc(
1423 const struct sctp_endpoint
*ep
,
1424 const union sctp_addr
*paddr
,
1425 struct sctp_transport
**);
1426 int sctp_endpoint_is_peeled_off(struct sctp_endpoint
*,
1427 const union sctp_addr
*);
1428 struct sctp_endpoint
*sctp_endpoint_is_match(struct sctp_endpoint
*,
1429 struct net
*, const union sctp_addr
*);
1430 int sctp_has_association(const union sctp_addr
*laddr
,
1431 const union sctp_addr
*paddr
);
1433 int sctp_verify_init(const struct sctp_association
*asoc
, sctp_cid_t
,
1434 sctp_init_chunk_t
*peer_init
, struct sctp_chunk
*chunk
,
1435 struct sctp_chunk
**err_chunk
);
1436 int sctp_process_init(struct sctp_association
*, struct sctp_chunk
*chunk
,
1437 const union sctp_addr
*peer
,
1438 sctp_init_chunk_t
*init
, gfp_t gfp
);
1439 __u32
sctp_generate_tag(const struct sctp_endpoint
*);
1440 __u32
sctp_generate_tsn(const struct sctp_endpoint
*);
1442 struct sctp_inithdr_host
{
1445 __u16 num_outbound_streams
;
1446 __u16 num_inbound_streams
;
1452 * 12. Recommended Transmission Control Block (TCB) Parameters
1454 * This section details a recommended set of parameters that should
1455 * be contained within the TCB for an implementation. This section is
1456 * for illustrative purposes and should not be deemed as requirements
1457 * on an implementation or as an exhaustive list of all parameters
1458 * inside an SCTP TCB. Each implementation may need its own additional
1459 * parameters for optimization.
1463 /* Here we have information about each individual association. */
1464 struct sctp_association
{
1466 /* A base structure common to endpoint and association.
1467 * In this context, it represents the associations's view
1468 * of the local endpoint of the association.
1470 struct sctp_ep_common base
;
1472 /* Associations on the same socket. */
1473 struct list_head asocs
;
1475 /* association id. */
1476 sctp_assoc_t assoc_id
;
1478 /* This is our parent endpoint. */
1479 struct sctp_endpoint
*ep
;
1481 /* These are those association elements needed in the cookie. */
1482 struct sctp_cookie c
;
1484 /* This is all information about our peer. */
1488 * Peer Rwnd : Current calculated value of the peer's rwnd.
1492 /* transport_addr_list
1494 * Peer : A list of SCTP transport addresses that the
1495 * Transport : peer is bound to. This information is derived
1496 * Address : from the INIT or INIT ACK and is used to
1497 * List : associate an inbound packet with a given
1498 * : association. Normally this information is
1499 * : hashed or keyed for quick lookup and access
1501 * : The list is also initialized with the list
1502 * : of addresses passed with the sctp_connectx()
1505 * It is a list of SCTP_transport's.
1507 struct list_head transport_addr_list
;
1511 * Peer : A count of the number of peer addresses
1512 * Transport : in the Peer Transport Address List.
1516 __u16 transport_count
;
1519 * The transport layer port number.
1525 * Primary : This is the current primary destination
1526 * Path : transport address of the peer endpoint. It
1527 * : may also specify a source transport address
1528 * : on this endpoint.
1530 * All of these paths live on transport_addr_list.
1532 * At the bakeoffs, we discovered that the intent of
1533 * primaryPath is that it only changes when the ULP
1534 * asks to have it changed. We add the activePath to
1535 * designate the connection we are currently using to
1536 * transmit new data and most control chunks.
1538 struct sctp_transport
*primary_path
;
1540 /* Cache the primary path address here, when we
1541 * need a an address for msg_name.
1543 union sctp_addr primary_addr
;
1546 * The path that we are currently using to
1547 * transmit new data and most control chunks.
1549 struct sctp_transport
*active_path
;
1553 * RFC2960 6.4 Multi-homed SCTP Endpoints
1555 * Furthermore, when its peer is multi-homed, an
1556 * endpoint SHOULD try to retransmit a chunk to an
1557 * active destination transport address that is
1558 * different from the last destination address to
1559 * which the DATA chunk was sent.
1561 struct sctp_transport
*retran_path
;
1563 /* Pointer to last transport I have sent on. */
1564 struct sctp_transport
*last_sent_to
;
1566 /* This is the last transport I have received DATA on. */
1567 struct sctp_transport
*last_data_from
;
1570 * Mapping An array of bits or bytes indicating which out of
1571 * Array order TSN's have been received (relative to the
1572 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1573 * order packets have been received, this array
1574 * will be set to all zero. This structure may be
1575 * in the form of a circular buffer or bit array.
1577 * Last Rcvd : This is the last TSN received in
1578 * TSN : sequence. This value is set initially by
1579 * : taking the peer's Initial TSN, received in
1580 * : the INIT or INIT ACK chunk, and subtracting
1583 * Throughout most of the specification this is called the
1584 * "Cumulative TSN ACK Point". In this case, we
1585 * ignore the advice in 12.2 in favour of the term
1586 * used in the bulk of the text. This value is hidden
1587 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1589 struct sctp_tsnmap tsn_map
;
1591 /* Ack State : This flag indicates if the next received
1592 * : packet is to be responded to with a
1593 * : SACK. This is initializedto 0. When a packet
1594 * : is received it is incremented. If this value
1595 * : reaches 2 or more, a SACK is sent and the
1596 * : value is reset to 0. Note: This is used only
1597 * : when no DATA chunks are received out of
1598 * : order. When DATA chunks are out of order,
1599 * : SACK's are not delayed (see Section 6).
1601 __u8 sack_needed
; /* Do we need to sack the peer? */
1603 __u32 sack_generation
;
1605 /* These are capabilities which our peer advertised. */
1606 __u8 ecn_capable
:1, /* Can peer do ECN? */
1607 ipv4_address
:1, /* Peer understands IPv4 addresses? */
1608 ipv6_address
:1, /* Peer understands IPv6 addresses? */
1609 hostname_address
:1, /* Peer understands DNS addresses? */
1610 asconf_capable
:1, /* Does peer support ADDIP? */
1611 prsctp_capable
:1, /* Can peer do PR-SCTP? */
1612 auth_capable
:1; /* Is peer doing SCTP-AUTH? */
1614 __u32 adaptation_ind
; /* Adaptation Code point. */
1616 /* This mask is used to disable sending the ASCONF chunk
1617 * with specified parameter to peer.
1619 __be16 addip_disabled_mask
;
1621 struct sctp_inithdr_host i
;
1625 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1626 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1627 * Initial TSN Value minus 1
1631 /* SCTP-AUTH: We need to know pears random number, hmac list
1632 * and authenticated chunk list. All that is part of the
1633 * cookie and these are just pointers to those locations
1635 sctp_random_param_t
*peer_random
;
1636 sctp_chunks_param_t
*peer_chunks
;
1637 sctp_hmac_algo_param_t
*peer_hmacs
;
1640 /* State : A state variable indicating what state the
1641 * : association is in, i.e. COOKIE-WAIT,
1642 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1643 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1645 * Note: No "CLOSED" state is illustrated since if a
1646 * association is "CLOSED" its TCB SHOULD be removed.
1648 * In this implementation we DO have a CLOSED
1649 * state which is used during initiation and shutdown.
1651 * State takes values from SCTP_STATE_*.
1655 /* The cookie life I award for any cookie. */
1656 struct timeval cookie_life
;
1658 /* Overall : The overall association error count.
1659 * Error Count : [Clear this any time I get something.]
1661 int overall_error_count
;
1663 /* These are the association's initial, max, and min RTO values.
1664 * These values will be initialized by system defaults, but can
1665 * be modified via the SCTP_RTOINFO socket option.
1667 unsigned long rto_initial
;
1668 unsigned long rto_max
;
1669 unsigned long rto_min
;
1671 /* Maximum number of new data packets that can be sent in a burst. */
1674 /* This is the max_retrans value for the association. This value will
1675 * be initialized initialized from system defaults, but can be
1676 * modified by the SCTP_ASSOCINFO socket option.
1680 /* This is the partially failed retrans value for the transport
1681 * and will be initialized from the assocs value. This can be
1682 * changed using the SCTP_PEER_ADDR_THLDS socket option
1686 /* Maximum number of times the endpoint will retransmit INIT */
1687 __u16 max_init_attempts
;
1689 /* How many times have we resent an INIT? */
1692 /* The largest timeout or RTO value to use in attempting an INIT */
1693 unsigned long max_init_timeo
;
1695 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1696 * the destination address every heartbeat interval. This value
1697 * will be inherited by all new transports.
1699 unsigned long hbinterval
;
1701 /* This is the max_retrans value for new transports in the
1706 /* Flag that path mtu update is pending */
1709 /* Association : The smallest PMTU discovered for all of the
1710 * PMTU : peer's transport addresses.
1714 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1717 /* SACK delay timeout */
1718 unsigned long sackdelay
;
1722 unsigned long timeouts
[SCTP_NUM_TIMEOUT_TYPES
];
1723 struct timer_list timers
[SCTP_NUM_TIMEOUT_TYPES
];
1725 /* Transport to which SHUTDOWN chunk was last sent. */
1726 struct sctp_transport
*shutdown_last_sent_to
;
1728 /* How many times have we resent a SHUTDOWN */
1729 int shutdown_retries
;
1731 /* Transport to which INIT chunk was last sent. */
1732 struct sctp_transport
*init_last_sent_to
;
1734 /* Next TSN : The next TSN number to be assigned to a new
1735 * : DATA chunk. This is sent in the INIT or INIT
1736 * : ACK chunk to the peer and incremented each
1737 * : time a DATA chunk is assigned a TSN
1738 * : (normally just prior to transmit or during
1744 * Last Rcvd : This is the last TSN received in sequence. This value
1745 * TSN : is set initially by taking the peer's Initial TSN,
1746 * : received in the INIT or INIT ACK chunk, and
1747 * : subtracting one from it.
1749 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1752 __u32 ctsn_ack_point
;
1754 /* PR-SCTP Advanced.Peer.Ack.Point */
1755 __u32 adv_peer_ack_point
;
1757 /* Highest TSN that is acknowledged by incoming SACKs. */
1758 __u32 highest_sacked
;
1760 /* TSN marking the fast recovery exit point */
1761 __u32 fast_recovery_exit
;
1763 /* Flag to track the current fast recovery state */
1766 /* The number of unacknowledged data chunks. Reported through
1767 * the SCTP_STATUS sockopt.
1771 /* The total number of data chunks that we've had to retransmit
1772 * as the result of a T3 timer expiration
1774 __u32 rtx_data_chunks
;
1776 /* This is the association's receive buffer space. This value is used
1777 * to set a_rwnd field in an INIT or a SACK chunk.
1781 /* This is the last advertised value of rwnd over a SACK chunk. */
1784 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1785 * to slop over a maximum of the association's frag_point.
1789 /* Keeps treack of rwnd pressure. This happens when we have
1790 * a window, but not recevie buffer (i.e small packets). This one
1791 * is releases slowly (1 PMTU at a time ).
1795 /* This is the sndbuf size in use for the association.
1796 * This corresponds to the sndbuf size for the association,
1797 * as specified in the sk->sndbuf.
1801 /* This is the amount of memory that this association has allocated
1802 * in the receive path at any given time.
1804 atomic_t rmem_alloc
;
1806 /* This is the wait queue head for send requests waiting on
1807 * the association sndbuf space.
1809 wait_queue_head_t wait
;
1811 /* The message size at which SCTP fragmentation will occur. */
1815 /* Counter used to count INIT errors. */
1816 int init_err_counter
;
1818 /* Count the number of INIT cycles (for doubling timeout). */
1821 /* Default send parameters. */
1822 __u16 default_stream
;
1823 __u16 default_flags
;
1825 __u32 default_context
;
1826 __u32 default_timetolive
;
1828 /* Default receive parameters */
1829 __u32 default_rcv_context
;
1831 /* This tracks outbound ssn for a given stream. */
1832 struct sctp_ssnmap
*ssnmap
;
1834 /* All outbound chunks go through this structure. */
1835 struct sctp_outq outqueue
;
1837 /* A smart pipe that will handle reordering and fragmentation,
1838 * as well as handle passing events up to the ULP.
1840 struct sctp_ulpq ulpq
;
1842 /* Last TSN that caused an ECNE Chunk to be sent. */
1843 __u32 last_ecne_tsn
;
1845 /* Last TSN that caused a CWR Chunk to be sent. */
1848 /* How many duplicated TSNs have we seen? */
1851 /* Number of seconds of idle time before an association is closed.
1852 * In the association context, this is really used as a boolean
1853 * since the real timeout is stored in the timeouts array
1857 /* These are to support
1858 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1859 * and Enforcement of Flow and Message Limits"
1860 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1861 * or "ADDIP" for short.
1866 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1868 * R1) One and only one ASCONF Chunk MAY be in transit and
1869 * unacknowledged at any one time. If a sender, after sending
1870 * an ASCONF chunk, decides it needs to transfer another
1871 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1872 * returns from the previous ASCONF Chunk before sending a
1873 * subsequent ASCONF. Note this restriction binds each side,
1874 * so at any time two ASCONF may be in-transit on any given
1875 * association (one sent from each endpoint).
1877 * [This is our one-and-only-one ASCONF in flight. If we do
1878 * not have an ASCONF in flight, this is NULL.]
1880 struct sctp_chunk
*addip_last_asconf
;
1882 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
1884 * This is needed to implement itmes E1 - E4 of the updated
1885 * spec. Here is the justification:
1887 * Since the peer may bundle multiple ASCONF chunks toward us,
1888 * we now need the ability to cache multiple ACKs. The section
1889 * describes in detail how they are cached and cleaned up.
1891 struct list_head asconf_ack_list
;
1893 /* These ASCONF chunks are waiting to be sent.
1895 * These chunaks can't be pushed to outqueue until receiving
1896 * ASCONF_ACK for the previous ASCONF indicated by
1897 * addip_last_asconf, so as to guarantee that only one ASCONF
1898 * is in flight at any time.
1900 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1902 * In defining the ASCONF Chunk transfer procedures, it is
1903 * essential that these transfers MUST NOT cause congestion
1904 * within the network. To achieve this, we place these
1905 * restrictions on the transfer of ASCONF Chunks:
1907 * R1) One and only one ASCONF Chunk MAY be in transit and
1908 * unacknowledged at any one time. If a sender, after sending
1909 * an ASCONF chunk, decides it needs to transfer another
1910 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1911 * returns from the previous ASCONF Chunk before sending a
1912 * subsequent ASCONF. Note this restriction binds each side,
1913 * so at any time two ASCONF may be in-transit on any given
1914 * association (one sent from each endpoint).
1917 * [I really think this is EXACTLY the sort of intelligence
1918 * which already resides in sctp_outq. Please move this
1919 * queue and its supporting logic down there. --piggy]
1921 struct list_head addip_chunk_list
;
1923 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1925 * A2) A serial number should be assigned to the Chunk. The
1926 * serial number SHOULD be a monotonically increasing
1927 * number. The serial number SHOULD be initialized at
1928 * the start of the association to the same value as the
1929 * Initial TSN and every time a new ASCONF chunk is created
1930 * it is incremented by one after assigning the serial number
1931 * to the newly created chunk.
1934 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
1936 * Serial Number : 32 bits (unsigned integer)
1938 * This value represents a Serial Number for the ASCONF
1939 * Chunk. The valid range of Serial Number is from 0 to
1940 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
1941 * after reaching 4294967295.
1944 union sctp_addr
*asconf_addr_del_pending
;
1945 int src_out_of_asoc_ok
;
1946 struct sctp_transport
*new_transport
;
1948 /* SCTP AUTH: list of the endpoint shared keys. These
1949 * keys are provided out of band by the user applicaton
1950 * and can't change during the lifetime of the association
1952 struct list_head endpoint_shared_keys
;
1955 * The current generated assocaition shared key (secret)
1957 struct sctp_auth_bytes
*asoc_shared_key
;
1959 /* SCTP AUTH: hmac id of the first peer requested algorithm
1962 __u16 default_hmac_id
;
1964 __u16 active_key_id
;
1966 __u8 need_ecne
:1, /* Need to send an ECNE Chunk? */
1967 temp
:1; /* Is it a temporary association? */
1971 /* An eyecatcher for determining if we are really looking at an
1972 * association data structure.
1975 SCTP_ASSOC_EYECATCHER
= 0xa550c123,
1978 /* Recover the outter association structure. */
1979 static inline struct sctp_association
*sctp_assoc(struct sctp_ep_common
*base
)
1981 struct sctp_association
*asoc
;
1983 asoc
= container_of(base
, struct sctp_association
, base
);
1987 /* These are function signatures for manipulating associations. */
1990 struct sctp_association
*
1991 sctp_association_new(const struct sctp_endpoint
*, const struct sock
*,
1992 sctp_scope_t scope
, gfp_t gfp
);
1993 void sctp_association_free(struct sctp_association
*);
1994 void sctp_association_put(struct sctp_association
*);
1995 void sctp_association_hold(struct sctp_association
*);
1997 struct sctp_transport
*sctp_assoc_choose_alter_transport(
1998 struct sctp_association
*, struct sctp_transport
*);
1999 void sctp_assoc_update_retran_path(struct sctp_association
*);
2000 struct sctp_transport
*sctp_assoc_lookup_paddr(const struct sctp_association
*,
2001 const union sctp_addr
*);
2002 int sctp_assoc_lookup_laddr(struct sctp_association
*asoc
,
2003 const union sctp_addr
*laddr
);
2004 struct sctp_transport
*sctp_assoc_add_peer(struct sctp_association
*,
2005 const union sctp_addr
*address
,
2007 const int peer_state
);
2008 void sctp_assoc_del_peer(struct sctp_association
*asoc
,
2009 const union sctp_addr
*addr
);
2010 void sctp_assoc_rm_peer(struct sctp_association
*asoc
,
2011 struct sctp_transport
*peer
);
2012 void sctp_assoc_control_transport(struct sctp_association
*,
2013 struct sctp_transport
*,
2014 sctp_transport_cmd_t
, sctp_sn_error_t
);
2015 struct sctp_transport
*sctp_assoc_lookup_tsn(struct sctp_association
*, __u32
);
2016 struct sctp_transport
*sctp_assoc_is_match(struct sctp_association
*,
2017 const union sctp_addr
*,
2018 const union sctp_addr
*);
2019 void sctp_assoc_migrate(struct sctp_association
*, struct sock
*);
2020 void sctp_assoc_update(struct sctp_association
*old
,
2021 struct sctp_association
*new);
2023 __u32
sctp_association_get_next_tsn(struct sctp_association
*);
2025 void sctp_assoc_sync_pmtu(struct sock
*, struct sctp_association
*);
2026 void sctp_assoc_rwnd_increase(struct sctp_association
*, unsigned int);
2027 void sctp_assoc_rwnd_decrease(struct sctp_association
*, unsigned int);
2028 void sctp_assoc_set_primary(struct sctp_association
*,
2029 struct sctp_transport
*);
2030 void sctp_assoc_del_nonprimary_peers(struct sctp_association
*,
2031 struct sctp_transport
*);
2032 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association
*,
2033 sctp_scope_t
, gfp_t
);
2034 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association
*,
2035 struct sctp_cookie
*,
2037 int sctp_assoc_set_id(struct sctp_association
*, gfp_t
);
2038 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association
*asoc
);
2039 struct sctp_chunk
*sctp_assoc_lookup_asconf_ack(
2040 const struct sctp_association
*asoc
,
2042 void sctp_asconf_queue_teardown(struct sctp_association
*asoc
);
2044 int sctp_cmp_addr_exact(const union sctp_addr
*ss1
,
2045 const union sctp_addr
*ss2
);
2046 struct sctp_chunk
*sctp_get_ecne_prepend(struct sctp_association
*asoc
);
2048 /* A convenience structure to parse out SCTP specific CMSGs. */
2049 typedef struct sctp_cmsgs
{
2050 struct sctp_initmsg
*init
;
2051 struct sctp_sndrcvinfo
*info
;
2054 /* Structure for tracking memory objects */
2058 } sctp_dbg_objcnt_entry_t
;
2060 #endif /* __sctp_structs_h__ */