1 /* SCTP kernel reference 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 reference Implementation
9 * The SCTP reference 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 * The SCTP reference 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 <asm/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. */
68 /* A convenience structure for handling sockaddr structures.
69 * We should wean ourselves off this.
72 struct sockaddr_in v4;
73 struct sockaddr_in6 v6;
77 /* Forward declarations for data structures. */
80 struct sctp_association;
81 struct sctp_transport;
86 struct sctp_bind_addr;
88 struct sctp_ep_common;
92 #include <net/sctp/tsnmap.h>
93 #include <net/sctp/ulpevent.h>
94 #include <net/sctp/ulpqueue.h>
96 /* Structures useful for managing bind/connect. */
98 struct sctp_bind_bucket {
100 unsigned short fastreuse;
101 struct sctp_bind_bucket *next;
102 struct sctp_bind_bucket **pprev;
103 struct hlist_head owner;
106 struct sctp_bind_hashbucket {
108 struct sctp_bind_bucket *chain;
111 /* Used for hashing all associations. */
112 struct sctp_hashbucket {
114 struct sctp_ep_common *chain;
115 } __attribute__((__aligned__(8)));
118 /* The SCTP globals structure. */
119 extern struct sctp_globals {
120 /* RFC2960 Section 14. Suggested SCTP Protocol Parameter Values
122 * The following protocol parameters are RECOMMENDED:
124 * RTO.Initial - 3 seconds
126 * RTO.Max - 60 seconds
127 * RTO.Alpha - 1/8 (3 when converted to right shifts.)
128 * RTO.Beta - 1/4 (2 when converted to right shifts.)
130 unsigned long rto_initial;
131 unsigned long rto_min;
132 unsigned long rto_max;
134 /* Note: rto_alpha and rto_beta are really defined as inverse
135 * powers of two to facilitate integer operations.
143 /* Whether Cookie Preservative is enabled(1) or not(0) */
144 int cookie_preserve_enable;
146 /* Valid.Cookie.Life - 60 seconds */
147 unsigned long valid_cookie_life;
149 /* Delayed SACK timeout 200ms default*/
150 unsigned long sack_timeout;
152 /* HB.interval - 30 seconds */
153 unsigned long hb_interval;
155 /* Association.Max.Retrans - 10 attempts
156 * Path.Max.Retrans - 5 attempts (per destination address)
157 * Max.Init.Retransmits - 8 attempts
159 int max_retrans_association;
160 int max_retrans_path;
161 int max_retrans_init;
164 * Policy for preforming sctp/socket accounting
165 * 0 - do socket level accounting, all assocs share sk_sndbuf
166 * 1 - do sctp accounting, each asoc may use sk_sndbuf bytes
171 * Policy for preforming sctp/socket accounting
172 * 0 - do socket level accounting, all assocs share sk_rcvbuf
173 * 1 - do sctp accounting, each asoc may use sk_rcvbuf bytes
177 /* The following variables are implementation specific. */
179 /* Default initialization values to be applied to new associations. */
181 __u16 max_outstreams;
183 /* This is a list of groups of functions for each address
184 * family that we support.
186 struct list_head address_families;
188 /* This is the hash of all endpoints. */
190 struct sctp_hashbucket *ep_hashtable;
192 /* This is the hash of all associations. */
194 struct sctp_hashbucket *assoc_hashtable;
196 /* This is the sctp port control hash. */
199 spinlock_t port_alloc_lock; /* Protects port_rover. */
200 struct sctp_bind_hashbucket *port_hashtable;
202 /* This is the global local address list.
203 * We actively maintain this complete list of interfaces on
204 * the system by catching routing events.
206 * It is a list of sctp_sockaddr_entry.
208 struct list_head local_addr_list;
209 spinlock_t local_addr_lock;
211 /* Flag to indicate if addip is enabled. */
214 /* Flag to indicate if PR-SCTP is enabled. */
218 #define sctp_rto_initial (sctp_globals.rto_initial)
219 #define sctp_rto_min (sctp_globals.rto_min)
220 #define sctp_rto_max (sctp_globals.rto_max)
221 #define sctp_rto_alpha (sctp_globals.rto_alpha)
222 #define sctp_rto_beta (sctp_globals.rto_beta)
223 #define sctp_max_burst (sctp_globals.max_burst)
224 #define sctp_valid_cookie_life (sctp_globals.valid_cookie_life)
225 #define sctp_cookie_preserve_enable (sctp_globals.cookie_preserve_enable)
226 #define sctp_max_retrans_association (sctp_globals.max_retrans_association)
227 #define sctp_sndbuf_policy (sctp_globals.sndbuf_policy)
228 #define sctp_rcvbuf_policy (sctp_globals.rcvbuf_policy)
229 #define sctp_max_retrans_path (sctp_globals.max_retrans_path)
230 #define sctp_max_retrans_init (sctp_globals.max_retrans_init)
231 #define sctp_sack_timeout (sctp_globals.sack_timeout)
232 #define sctp_hb_interval (sctp_globals.hb_interval)
233 #define sctp_max_instreams (sctp_globals.max_instreams)
234 #define sctp_max_outstreams (sctp_globals.max_outstreams)
235 #define sctp_address_families (sctp_globals.address_families)
236 #define sctp_ep_hashsize (sctp_globals.ep_hashsize)
237 #define sctp_ep_hashtable (sctp_globals.ep_hashtable)
238 #define sctp_assoc_hashsize (sctp_globals.assoc_hashsize)
239 #define sctp_assoc_hashtable (sctp_globals.assoc_hashtable)
240 #define sctp_port_hashsize (sctp_globals.port_hashsize)
241 #define sctp_port_rover (sctp_globals.port_rover)
242 #define sctp_port_alloc_lock (sctp_globals.port_alloc_lock)
243 #define sctp_port_hashtable (sctp_globals.port_hashtable)
244 #define sctp_local_addr_list (sctp_globals.local_addr_list)
245 #define sctp_local_addr_lock (sctp_globals.local_addr_lock)
246 #define sctp_addip_enable (sctp_globals.addip_enable)
247 #define sctp_prsctp_enable (sctp_globals.prsctp_enable)
249 /* SCTP Socket type: UDP or TCP style. */
252 SCTP_SOCKET_UDP_HIGH_BANDWIDTH,
254 } sctp_socket_type_t;
256 /* Per socket SCTP information. */
258 /* inet_sock has to be the first member of sctp_sock */
259 struct inet_sock inet;
260 /* What kind of a socket is this? */
261 sctp_socket_type_t type;
263 /* PF_ family specific functions. */
266 /* Access to HMAC transform. */
267 struct crypto_tfm *hmac;
269 /* What is our base endpointer? */
270 struct sctp_endpoint *ep;
272 struct sctp_bind_bucket *bind_hash;
273 /* Various Socket Options. */
274 __u16 default_stream;
277 __u32 default_context;
278 __u32 default_timetolive;
280 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
281 * the destination address every heartbeat interval. This value
282 * will be inherited by all new associations.
286 /* This is the max_retrans value for new associations. */
289 /* The initial Path MTU to use for new associations. */
292 /* The default SACK delay timeout for new associations. */
295 /* Flags controling Heartbeat, SACK delay, and Path MTU Discovery. */
298 struct sctp_initmsg initmsg;
299 struct sctp_rtoinfo rtoinfo;
300 struct sctp_paddrparams paddrparam;
301 struct sctp_event_subscribe subscribe;
302 struct sctp_assocparams assocparams;
306 __u8 disable_fragments;
311 /* Receive to here while partial delivery is in effect. */
312 struct sk_buff_head pd_lobby;
315 static inline struct sctp_sock *sctp_sk(const struct sock *sk)
317 return (struct sctp_sock *)sk;
320 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
322 return (struct sock *)sp;
325 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
327 struct sctp_sock sctp;
328 struct ipv6_pinfo inet6;
330 #endif /* CONFIG_IPV6 */
333 /* This is our APPLICATION-SPECIFIC state cookie.
334 * THIS IS NOT DICTATED BY THE SPECIFICATION.
336 /* These are the parts of an association which we send in the cookie.
337 * Most of these are straight out of:
338 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
344 /* My : Tag expected in every inbound packet and sent
345 * Verification: in the INIT or INIT ACK chunk.
350 /* Peer's : Tag expected in every outbound packet except
351 * Verification: in the INIT chunk.
356 /* The rest of these are not from the spec, but really need to
360 /* My Tie Tag : Assist in discovering a restarting association. */
363 /* Peer's Tie Tag: Assist in discovering a restarting association. */
366 /* When does this cookie expire? */
367 struct timeval expiration;
369 /* Number of inbound/outbound streams which are set
370 * and negotiated during the INIT process.
372 __u16 sinit_num_ostreams;
373 __u16 sinit_max_instreams;
375 /* This is the first sequence number I used. */
378 /* This holds the originating address of the INIT packet. */
379 union sctp_addr peer_addr;
382 * Include the source port of the INIT-ACK
388 /* Padding for future use */
394 /* This is a shim for my peer's INIT packet, followed by
395 * a copy of the raw address list of the association.
396 * The length of the raw address list is saved in the
397 * raw_addr_list_len field, which will be used at the time when
398 * the association TCB is re-constructed from the cookie.
400 __u32 raw_addr_list_len;
401 struct sctp_init_chunk peer_init[0];
405 /* The format of our cookie that we send to our peer. */
406 struct sctp_signed_cookie {
407 __u8 signature[SCTP_SECRET_SIZE];
408 __u32 __pad; /* force sctp_cookie alignment to 64 bits */
409 struct sctp_cookie c;
410 } __attribute__((packed));
412 /* This is another convenience type to allocate memory for address
413 * params for the maximum size and pass such structures around
416 union sctp_addr_param {
417 struct sctp_ipv4addr_param v4;
418 struct sctp_ipv6addr_param v6;
421 /* A convenience type to allow walking through the various
422 * parameters and avoid casting all over the place.
426 struct sctp_paramhdr *p;
427 struct sctp_cookie_preserve_param *life;
428 struct sctp_hostname_param *dns;
429 struct sctp_cookie_param *cookie;
430 struct sctp_supported_addrs_param *sat;
431 struct sctp_ipv4addr_param *v4;
432 struct sctp_ipv6addr_param *v6;
433 union sctp_addr_param *addr;
434 struct sctp_adaption_ind_param *aind;
437 /* RFC 2960. Section 3.3.5 Heartbeat.
438 * Heartbeat Information: variable length
439 * The Sender-specific Heartbeat Info field should normally include
440 * information about the sender's current time when this HEARTBEAT
441 * chunk is sent and the destination transport address to which this
442 * HEARTBEAT is sent (see Section 8.3).
444 typedef struct sctp_sender_hb_info {
445 struct sctp_paramhdr param_hdr;
446 union sctp_addr daddr;
447 unsigned long sent_at;
448 } __attribute__((packed)) sctp_sender_hb_info_t;
451 * RFC 2960 1.3.2 Sequenced Delivery within Streams
453 * The term "stream" is used in SCTP to refer to a sequence of user
454 * messages that are to be delivered to the upper-layer protocol in
455 * order with respect to other messages within the same stream. This is
456 * in contrast to its usage in TCP, where it refers to a sequence of
457 * bytes (in this document a byte is assumed to be eight bits).
460 * This is the structure we use to track both our outbound and inbound
461 * SSN, or Stream Sequence Numbers.
470 struct sctp_stream in;
471 struct sctp_stream out;
475 struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out,
477 void sctp_ssnmap_free(struct sctp_ssnmap *map);
478 void sctp_ssnmap_clear(struct sctp_ssnmap *map);
480 /* What is the current SSN number for this stream? */
481 static inline __u16 sctp_ssn_peek(struct sctp_stream *stream, __u16 id)
483 return stream->ssn[id];
486 /* Return the next SSN number for this stream. */
487 static inline __u16 sctp_ssn_next(struct sctp_stream *stream, __u16 id)
489 return stream->ssn[id]++;
492 /* Skip over this ssn and all below. */
493 static inline void sctp_ssn_skip(struct sctp_stream *stream, __u16 id,
496 stream->ssn[id] = ssn+1;
500 * Pointers to address related SCTP functions.
501 * (i.e. things that depend on the address family.)
504 int (*sctp_xmit) (struct sk_buff *skb,
505 struct sctp_transport *,
507 int (*setsockopt) (struct sock *sk,
512 int (*getsockopt) (struct sock *sk,
517 struct dst_entry *(*get_dst) (struct sctp_association *asoc,
518 union sctp_addr *daddr,
519 union sctp_addr *saddr);
520 void (*get_saddr) (struct sctp_association *asoc,
521 struct dst_entry *dst,
522 union sctp_addr *daddr,
523 union sctp_addr *saddr);
524 void (*copy_addrlist) (struct list_head *,
525 struct net_device *);
526 void (*dst_saddr) (union sctp_addr *saddr,
527 struct dst_entry *dst,
528 unsigned short port);
529 int (*cmp_addr) (const union sctp_addr *addr1,
530 const union sctp_addr *addr2);
531 void (*addr_copy) (union sctp_addr *dst,
532 union sctp_addr *src);
533 void (*from_skb) (union sctp_addr *,
536 void (*from_sk) (union sctp_addr *,
538 void (*to_sk_saddr) (union sctp_addr *,
540 void (*to_sk_daddr) (union sctp_addr *,
542 void (*from_addr_param) (union sctp_addr *,
543 union sctp_addr_param *,
544 __u16 port, int iif);
545 int (*to_addr_param) (const union sctp_addr *,
546 union sctp_addr_param *);
547 int (*addr_valid) (union sctp_addr *,
549 const struct sk_buff *);
550 sctp_scope_t (*scope) (union sctp_addr *);
551 void (*inaddr_any) (union sctp_addr *, unsigned short);
552 int (*is_any) (const union sctp_addr *);
553 int (*available) (union sctp_addr *,
555 int (*skb_iif) (const struct sk_buff *sk);
556 int (*is_ce) (const struct sk_buff *sk);
557 void (*seq_dump_addr)(struct seq_file *seq,
558 union sctp_addr *addr);
559 __u16 net_header_len;
561 sa_family_t sa_family;
562 struct list_head list;
565 struct sctp_af *sctp_get_af_specific(sa_family_t);
566 int sctp_register_af(struct sctp_af *);
568 /* Protocol family functions. */
570 void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
571 void (*skb_msgname) (struct sk_buff *, char *, int *);
572 int (*af_supported) (sa_family_t, struct sctp_sock *);
573 int (*cmp_addr) (const union sctp_addr *,
574 const union sctp_addr *,
576 int (*bind_verify) (struct sctp_sock *, union sctp_addr *);
577 int (*send_verify) (struct sctp_sock *, union sctp_addr *);
578 int (*supported_addrs)(const struct sctp_sock *, __u16 *);
579 struct sock *(*create_accept_sk) (struct sock *sk,
580 struct sctp_association *asoc);
581 void (*addr_v4map) (struct sctp_sock *, union sctp_addr *);
586 /* Structure to track chunk fragments that have been acked, but peer
587 * fragments of the same message have not.
589 struct sctp_datamsg {
590 /* Chunks waiting to be submitted to lower layer. */
591 struct list_head chunks;
592 /* Chunks that have been transmitted. */
593 struct list_head track;
594 /* Reference counting. */
596 /* When is this message no longer interesting to the peer? */
597 unsigned long expires_at;
598 /* Did the messenge fail to send? */
601 /* Control whether chunks from this message can be abandoned. */
605 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
606 struct sctp_sndrcvinfo *,
607 struct msghdr *, int len);
608 void sctp_datamsg_put(struct sctp_datamsg *);
609 void sctp_datamsg_free(struct sctp_datamsg *);
610 void sctp_datamsg_track(struct sctp_chunk *);
611 void sctp_chunk_fail(struct sctp_chunk *, int error);
612 int sctp_chunk_abandoned(struct sctp_chunk *);
614 /* RFC2960 1.4 Key Terms
616 * o Chunk: A unit of information within an SCTP packet, consisting of
617 * a chunk header and chunk-specific content.
619 * As a matter of convenience, we remember the SCTP common header for
620 * each chunk as well as a few other header pointers...
623 struct list_head list;
627 /* This is our link to the per-transport transmitted list. */
628 struct list_head transmitted_list;
630 /* This field is used by chunks that hold fragmented data.
631 * For the first fragment this is the list that holds the rest of
632 * fragments. For the remaining fragments, this is the link to the
633 * frag_list maintained in the first fragment.
635 struct list_head frag_list;
637 /* This points to the sk_buff containing the actual data. */
640 /* These are the SCTP headers by reverse order in a packet.
641 * Note that some of these may happen more than once. In that
642 * case, we point at the "current" one, whatever that means
643 * for that level of header.
646 /* We point this at the FIRST TLV parameter to chunk_hdr. */
647 union sctp_params param_hdr;
650 struct sctp_datahdr *data_hdr;
651 struct sctp_inithdr *init_hdr;
652 struct sctp_sackhdr *sack_hdr;
653 struct sctp_heartbeathdr *hb_hdr;
654 struct sctp_sender_hb_info *hbs_hdr;
655 struct sctp_shutdownhdr *shutdown_hdr;
656 struct sctp_signed_cookie *cookie_hdr;
657 struct sctp_ecnehdr *ecne_hdr;
658 struct sctp_cwrhdr *ecn_cwr_hdr;
659 struct sctp_errhdr *err_hdr;
660 struct sctp_addiphdr *addip_hdr;
661 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
666 struct sctp_chunkhdr *chunk_hdr;
667 struct sctphdr *sctp_hdr;
669 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
670 struct sctp_sndrcvinfo sinfo;
672 /* Which association does this belong to? */
673 struct sctp_association *asoc;
675 /* What endpoint received this chunk? */
676 struct sctp_ep_common *rcvr;
678 /* We fill this in if we are calculating RTT. */
679 unsigned long sent_at;
681 /* What is the origin IP address for this chunk? */
682 union sctp_addr source;
683 /* Destination address for this chunk. */
684 union sctp_addr dest;
686 /* For outbound message, track all fragments for SEND_FAILED. */
687 struct sctp_datamsg *msg;
689 /* For an inbound chunk, this tells us where it came from.
690 * For an outbound chunk, it tells us where we'd like it to
691 * go. It is NULL if we have no preference.
693 struct sctp_transport *transport;
695 __u8 rtt_in_progress; /* Is this chunk used for RTT calculation? */
696 __u8 resent; /* Has this chunk ever been retransmitted. */
697 __u8 has_tsn; /* Does this chunk have a TSN yet? */
698 __u8 has_ssn; /* Does this chunk have a SSN yet? */
699 __u8 singleton; /* Was this the only chunk in the packet? */
700 __u8 end_of_packet; /* Was this the last chunk in the packet? */
701 __u8 ecn_ce_done; /* Have we processed the ECN CE bit? */
702 __u8 pdiscard; /* Discard the whole packet now? */
703 __u8 tsn_gap_acked; /* Is this chunk acked by a GAP ACK? */
704 __s8 fast_retransmit; /* Is this chunk fast retransmitted? */
705 __u8 tsn_missing_report; /* Data chunk missing counter. */
706 __u8 data_accepted; /* At least 1 chunk in this packet accepted */
709 void sctp_chunk_hold(struct sctp_chunk *);
710 void sctp_chunk_put(struct sctp_chunk *);
711 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
713 void sctp_chunk_free(struct sctp_chunk *);
714 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
715 struct sctp_chunk *sctp_chunkify(struct sk_buff *,
716 const struct sctp_association *,
718 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
720 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
722 /* This is a structure for holding either an IPv6 or an IPv4 address. */
723 /* sin_family -- AF_INET or AF_INET6
724 * sin_port -- ordinary port number
725 * sin_addr -- cast to either (struct in_addr) or (struct in6_addr)
727 struct sctp_sockaddr_entry {
728 struct list_head list;
732 typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *);
734 /* This structure holds lists of chunks as we are assembling for
738 /* These are the SCTP header values (host order) for the packet. */
740 __u16 destination_port;
743 /* This contains the payload chunks. */
744 struct list_head chunk_list;
746 /* This is the overhead of the sctp and ip headers. */
748 /* This is the total size of all chunks INCLUDING padding. */
751 /* The packet is destined for this transport address.
752 * The function we finally use to pass down to the next lower
753 * layer lives in the transport structure.
755 struct sctp_transport *transport;
757 /* This packet contains a COOKIE-ECHO chunk. */
758 char has_cookie_echo;
760 /* This packet containsa SACK chunk. */
763 /* SCTP cannot fragment this packet. So let ip fragment it. */
769 struct sctp_packet *sctp_packet_init(struct sctp_packet *,
770 struct sctp_transport *,
771 __u16 sport, __u16 dport);
772 struct sctp_packet *sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
773 sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *,
774 struct sctp_chunk *);
775 sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *,
776 struct sctp_chunk *);
777 int sctp_packet_transmit(struct sctp_packet *);
778 void sctp_packet_free(struct sctp_packet *);
780 static inline int sctp_packet_empty(struct sctp_packet *packet)
782 return (packet->size == packet->overhead);
785 /* This represents a remote transport address.
786 * For local transport addresses, we just use union sctp_addr.
788 * RFC2960 Section 1.4 Key Terms
790 * o Transport address: A Transport Address is traditionally defined
791 * by Network Layer address, Transport Layer protocol and Transport
792 * Layer port number. In the case of SCTP running over IP, a
793 * transport address is defined by the combination of an IP address
794 * and an SCTP port number (where SCTP is the Transport protocol).
796 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
798 * o The sender keeps a separate congestion control parameter set for
799 * each of the destination addresses it can send to (not each
800 * source-destination pair but for each destination). The parameters
801 * should decay if the address is not used for a long enough time
805 struct sctp_transport {
806 /* A list of transports. */
807 struct list_head transports;
809 /* Reference counting. */
813 /* This is the peer's IP address and port. */
814 union sctp_addr ipaddr;
816 /* These are the functions we call to handle LLP stuff. */
817 struct sctp_af *af_specific;
819 /* Which association do we belong to? */
820 struct sctp_association *asoc;
824 * 12.3 Per Transport Address Data
826 * For each destination transport address in the peer's
827 * address list derived from the INIT or INIT ACK chunk, a
828 * number of data elements needs to be maintained including:
830 __u32 rtt; /* This is the most recent RTT. */
832 /* RTO : The current retransmission timeout value. */
835 /* RTTVAR : The current RTT variation. */
838 /* SRTT : The current smoothed round trip time. */
841 /* RTO-Pending : A flag used to track if one of the DATA
842 * chunks sent to this address is currently being
843 * used to compute a RTT. If this flag is 0,
844 * the next DATA chunk sent to this destination
845 * should be used to compute a RTT and this flag
846 * should be set. Every time the RTT
847 * calculation completes (i.e. the DATA chunk
848 * is SACK'd) clear this flag.
853 * These are the congestion stats.
855 /* cwnd : The current congestion window. */
856 __u32 cwnd; /* This is the actual cwnd. */
858 /* ssthresh : The current slow start threshold value. */
861 /* partial : The tracking method for increase of cwnd when in
862 * bytes acked : congestion avoidance mode (see Section 6.2.2)
864 __u32 partial_bytes_acked;
866 /* Data that has been sent, but not acknowledged. */
870 struct dst_entry *dst;
871 /* Source address. */
872 union sctp_addr saddr;
874 /* When was the last time(in jiffies) that a data packet was sent on
875 * this transport? This is used to adjust the cwnd when the transport
878 unsigned long last_time_used;
880 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
881 * the destination address every heartbeat interval.
883 unsigned long hbinterval;
885 /* SACK delay timeout */
886 unsigned long sackdelay;
888 /* When was the last time (in jiffies) that we heard from this
889 * transport? We use this to pick new active and retran paths.
891 unsigned long last_time_heard;
893 /* Last time(in jiffies) when cwnd is reduced due to the congestion
894 * indication based on ECNE chunk.
896 unsigned long last_time_ecne_reduced;
898 /* This is the max_retrans value for the transport and will
899 * be initialized from the assocs value. This can be changed
900 * using SCTP_SET_PEER_ADDR_PARAMS socket option.
904 /* PMTU : The current known path MTU. */
907 /* Flags controling Heartbeat, SACK delay, and Path MTU Discovery. */
910 /* The number of times INIT has been sent on this transport. */
913 /* state : The current state of this destination,
914 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKOWN.
918 /* These are the error stats for this destination. */
920 /* Error count : The current error count for this destination. */
921 unsigned short error_count;
923 /* Per : A timer used by each destination.
927 * [Everywhere else in the text this is called T3-rtx. -ed]
929 struct timer_list T3_rtx_timer;
931 /* Heartbeat timer is per destination. */
932 struct timer_list hb_timer;
934 /* Since we're using per-destination retransmission timers
935 * (see above), we're also using per-destination "transmitted"
936 * queues. This probably ought to be a private struct
937 * accessible only within the outqueue, but it's not, yet.
939 struct list_head transmitted;
941 /* We build bundle-able packets for this transport here. */
942 struct sctp_packet packet;
944 /* This is the list of transports that have chunks to send. */
945 struct list_head send_ready;
947 int malloced; /* Is this structure kfree()able? */
949 /* State information saved for SFR_CACC algorithm. The key
950 * idea in SFR_CACC is to maintain state at the sender on a
951 * per-destination basis when a changeover happens.
952 * char changeover_active;
953 * char cycling_changeover;
954 * __u32 next_tsn_at_change;
955 * char cacc_saw_newack;
958 /* An unsigned integer, which stores the next TSN to be
959 * used by the sender, at the moment of changeover.
961 __u32 next_tsn_at_change;
963 /* A flag which indicates the occurrence of a changeover */
964 char changeover_active;
966 /* A flag which indicates whether the change of primary is
967 * the first switch to this destination address during an
970 char cycling_changeover;
972 /* A temporary flag, which is used during the processing of
973 * a SACK to estimate the causative TSN(s)'s group.
975 char cacc_saw_newack;
979 struct sctp_transport *sctp_transport_new(const union sctp_addr *,
981 void sctp_transport_set_owner(struct sctp_transport *,
982 struct sctp_association *);
983 void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
985 void sctp_transport_pmtu(struct sctp_transport *);
986 void sctp_transport_free(struct sctp_transport *);
987 void sctp_transport_reset_timers(struct sctp_transport *);
988 void sctp_transport_hold(struct sctp_transport *);
989 void sctp_transport_put(struct sctp_transport *);
990 void sctp_transport_update_rto(struct sctp_transport *, __u32);
991 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
992 void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t);
993 unsigned long sctp_transport_timeout(struct sctp_transport *);
996 /* This is the structure we use to queue packets as they come into
997 * SCTP. We write packets to it and read chunks from it.
1000 /* This is actually a queue of sctp_chunk each
1001 * containing a partially decoded packet.
1003 struct list_head in_chunk_list;
1004 /* This is the packet which is currently off the in queue and is
1005 * being worked on through the inbound chunk processing.
1007 struct sctp_chunk *in_progress;
1009 /* This is the delayed task to finish delivering inbound
1012 struct work_struct immediate;
1014 int malloced; /* Is this structure kfree()able? */
1017 void sctp_inq_init(struct sctp_inq *);
1018 void sctp_inq_free(struct sctp_inq *);
1019 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
1020 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
1021 void sctp_inq_set_th_handler(struct sctp_inq *, void (*)(void *), void *);
1023 /* This is the structure we use to hold outbound chunks. You push
1024 * chunks in and they automatically pop out the other end as bundled
1025 * packets (it calls (*output_handler)()).
1027 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1028 * and 8.2 of the v13 draft.
1030 * It handles retransmissions. The connection to the timeout portion
1031 * of the state machine is through sctp_..._timeout() and timeout_handler.
1033 * If you feed it SACKs, it will eat them.
1035 * If you give it big chunks, it will fragment them.
1037 * It assigns TSN's to data chunks. This happens at the last possible
1038 * instant before transmission.
1040 * When free()'d, it empties itself out via output_handler().
1043 struct sctp_association *asoc;
1045 /* Data pending that has never been transmitted. */
1046 struct list_head out_chunk_list;
1048 unsigned out_qlen; /* Total length of queued data chunks. */
1050 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1053 /* These are control chunks we want to send. */
1054 struct list_head control_chunk_list;
1056 /* These are chunks that have been sacked but are above the
1057 * CTSN, or cumulative tsn ack point.
1059 struct list_head sacked;
1061 /* Put chunks on this list to schedule them for
1064 struct list_head retransmit;
1066 /* Put chunks on this list to save them for FWD TSN processing as
1067 * they were abandoned.
1069 struct list_head abandoned;
1071 /* How many unackd bytes do we have in-flight? */
1072 __u32 outstanding_bytes;
1077 /* Is this structure empty? */
1080 /* Are we kfree()able? */
1084 void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1085 void sctp_outq_teardown(struct sctp_outq *);
1086 void sctp_outq_free(struct sctp_outq*);
1087 int sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk);
1088 int sctp_outq_flush(struct sctp_outq *, int);
1089 int sctp_outq_sack(struct sctp_outq *, struct sctp_sackhdr *);
1090 int sctp_outq_is_empty(const struct sctp_outq *);
1091 void sctp_outq_restart(struct sctp_outq *);
1093 void sctp_retransmit(struct sctp_outq *, struct sctp_transport *,
1094 sctp_retransmit_reason_t);
1095 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1096 int sctp_outq_uncork(struct sctp_outq *);
1097 /* Uncork and flush an outqueue. */
1098 static inline void sctp_outq_cork(struct sctp_outq *q)
1103 /* These bind address data fields common between endpoints and associations */
1104 struct sctp_bind_addr {
1106 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1108 * SCTP Port: The local SCTP port number the endpoint is
1113 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1115 * Address List: The list of IP addresses that this instance
1116 * has bound. This information is passed to one's
1117 * peer(s) in INIT and INIT ACK chunks.
1119 struct list_head address_list;
1121 int malloced; /* Are we kfree()able? */
1124 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1125 void sctp_bind_addr_free(struct sctp_bind_addr *);
1126 int sctp_bind_addr_copy(struct sctp_bind_addr *dest,
1127 const struct sctp_bind_addr *src,
1128 sctp_scope_t scope, gfp_t gfp,
1130 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1132 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1133 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1134 struct sctp_sock *);
1135 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp,
1136 const union sctp_addr *addrs,
1138 struct sctp_sock *opt);
1139 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1142 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1143 __u16 port, gfp_t gfp);
1145 sctp_scope_t sctp_scope(const union sctp_addr *);
1146 int sctp_in_scope(const union sctp_addr *addr, const sctp_scope_t scope);
1147 int sctp_is_any(const union sctp_addr *addr);
1148 int sctp_addr_is_valid(const union sctp_addr *addr);
1151 /* What type of endpoint? */
1153 SCTP_EP_TYPE_SOCKET,
1154 SCTP_EP_TYPE_ASSOCIATION,
1155 } sctp_endpoint_type_t;
1158 * A common base class to bridge the implmentation view of a
1159 * socket (usually listening) endpoint versus an association's
1161 * This common structure is useful for several purposes:
1162 * 1) Common interface for lookup routines.
1163 * a) Subfunctions work for either endpoint or association
1164 * b) Single interface to lookup allows hiding the lookup lock rather
1165 * than acquiring it externally.
1166 * 2) Common interface for the inbound chunk handling/state machine.
1167 * 3) Common object handling routines for reference counting, etc.
1168 * 4) Disentangle association lookup from endpoint lookup, where we
1169 * do not have to find our endpoint to find our association.
1173 struct sctp_ep_common {
1174 /* Fields to help us manage our entries in the hash tables. */
1175 struct sctp_ep_common *next;
1176 struct sctp_ep_common **pprev;
1179 /* Runtime type information. What kind of endpoint is this? */
1180 sctp_endpoint_type_t type;
1182 /* Some fields to help us manage this object.
1183 * refcnt - Reference count access to this object.
1184 * dead - Do not attempt to use this object.
1185 * malloced - Do we need to kfree this object?
1191 /* What socket does this endpoint belong to? */
1194 /* This is where we receive inbound chunks. */
1195 struct sctp_inq inqueue;
1197 /* This substructure includes the defining parameters of the
1199 * bind_addr.port is our shared port number.
1200 * bind_addr.address_list is our set of local IP addresses.
1202 struct sctp_bind_addr bind_addr;
1204 /* Protection during address list comparisons. */
1209 /* RFC Section 1.4 Key Terms
1211 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1212 * multi-homed host, an SCTP endpoint is represented to its peers as a
1213 * combination of a set of eligible destination transport addresses to
1214 * which SCTP packets can be sent and a set of eligible source
1215 * transport addresses from which SCTP packets can be received.
1216 * All transport addresses used by an SCTP endpoint must use the
1217 * same port number, but can use multiple IP addresses. A transport
1218 * address used by an SCTP endpoint must not be used by another
1219 * SCTP endpoint. In other words, a transport address is unique
1220 * to an SCTP endpoint.
1222 * From an implementation perspective, each socket has one of these.
1223 * A TCP-style socket will have exactly one association on one of
1224 * these. An UDP-style socket will have multiple associations hanging
1228 struct sctp_endpoint {
1229 /* Common substructure for endpoint and association. */
1230 struct sctp_ep_common base;
1232 /* Associations: A list of current associations and mappings
1233 * to the data consumers for each association. This
1234 * may be in the form of a hash table or other
1235 * implementation dependent structure. The data
1236 * consumers may be process identification
1237 * information such as file descriptors, named pipe
1238 * pointer, or table pointers dependent on how SCTP
1241 /* This is really a list of struct sctp_association entries. */
1242 struct list_head asocs;
1244 /* Secret Key: A secret key used by this endpoint to compute
1245 * the MAC. This SHOULD be a cryptographic quality
1246 * random number with a sufficient length.
1247 * Discussion in [RFC1750] can be helpful in
1248 * selection of the key.
1250 __u8 secret_key[SCTP_HOW_MANY_SECRETS][SCTP_SECRET_SIZE];
1255 /* digest: This is a digest of the sctp cookie. This field is
1256 * only used on the receive path when we try to validate
1257 * that the cookie has not been tampered with. We put
1258 * this here so we pre-allocate this once and can re-use
1261 __u8 digest[SCTP_SIGNATURE_SIZE];
1263 /* sendbuf acct. policy. */
1264 __u32 sndbuf_policy;
1266 /* rcvbuf acct. policy. */
1267 __u32 rcvbuf_policy;
1270 /* Recover the outter endpoint structure. */
1271 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1273 struct sctp_endpoint *ep;
1275 ep = container_of(base, struct sctp_endpoint, base);
1279 /* These are function signatures for manipulating endpoints. */
1280 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1281 void sctp_endpoint_free(struct sctp_endpoint *);
1282 void sctp_endpoint_put(struct sctp_endpoint *);
1283 void sctp_endpoint_hold(struct sctp_endpoint *);
1284 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1285 struct sctp_association *sctp_endpoint_lookup_assoc(
1286 const struct sctp_endpoint *ep,
1287 const union sctp_addr *paddr,
1288 struct sctp_transport **);
1289 int sctp_endpoint_is_peeled_off(struct sctp_endpoint *,
1290 const union sctp_addr *);
1291 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1292 const union sctp_addr *);
1293 int sctp_has_association(const union sctp_addr *laddr,
1294 const union sctp_addr *paddr);
1296 int sctp_verify_init(const struct sctp_association *asoc, sctp_cid_t,
1297 sctp_init_chunk_t *peer_init, struct sctp_chunk *chunk,
1298 struct sctp_chunk **err_chunk);
1299 int sctp_process_init(struct sctp_association *, sctp_cid_t cid,
1300 const union sctp_addr *peer,
1301 sctp_init_chunk_t *init, gfp_t gfp);
1302 __u32 sctp_generate_tag(const struct sctp_endpoint *);
1303 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
1308 * 12. Recommended Transmission Control Block (TCB) Parameters
1310 * This section details a recommended set of parameters that should
1311 * be contained within the TCB for an implementation. This section is
1312 * for illustrative purposes and should not be deemed as requirements
1313 * on an implementation or as an exhaustive list of all parameters
1314 * inside an SCTP TCB. Each implementation may need its own additional
1315 * parameters for optimization.
1319 /* Here we have information about each individual association. */
1320 struct sctp_association {
1322 /* A base structure common to endpoint and association.
1323 * In this context, it represents the associations's view
1324 * of the local endpoint of the association.
1326 struct sctp_ep_common base;
1328 /* Associations on the same socket. */
1329 struct list_head asocs;
1331 /* association id. */
1332 sctp_assoc_t assoc_id;
1334 /* This is our parent endpoint. */
1335 struct sctp_endpoint *ep;
1337 /* These are those association elements needed in the cookie. */
1338 struct sctp_cookie c;
1340 /* This is all information about our peer. */
1344 * Peer Rwnd : Current calculated value of the peer's rwnd.
1348 /* transport_addr_list
1350 * Peer : A list of SCTP transport addresses that the
1351 * Transport : peer is bound to. This information is derived
1352 * Address : from the INIT or INIT ACK and is used to
1353 * List : associate an inbound packet with a given
1354 * : association. Normally this information is
1355 * : hashed or keyed for quick lookup and access
1357 * : The list is also initialized with the list
1358 * : of addresses passed with the sctp_connectx()
1361 * It is a list of SCTP_transport's.
1363 struct list_head transport_addr_list;
1367 * Peer : A count of the number of peer addresses
1368 * Transport : in the Peer Transport Address List.
1372 __u16 transport_count;
1375 * The transport layer port number.
1381 * Primary : This is the current primary destination
1382 * Path : transport address of the peer endpoint. It
1383 * : may also specify a source transport address
1384 * : on this endpoint.
1386 * All of these paths live on transport_addr_list.
1388 * At the bakeoffs, we discovered that the intent of
1389 * primaryPath is that it only changes when the ULP
1390 * asks to have it changed. We add the activePath to
1391 * designate the connection we are currently using to
1392 * transmit new data and most control chunks.
1394 struct sctp_transport *primary_path;
1396 /* Cache the primary path address here, when we
1397 * need a an address for msg_name.
1399 union sctp_addr primary_addr;
1402 * The path that we are currently using to
1403 * transmit new data and most control chunks.
1405 struct sctp_transport *active_path;
1409 * RFC2960 6.4 Multi-homed SCTP Endpoints
1411 * Furthermore, when its peer is multi-homed, an
1412 * endpoint SHOULD try to retransmit a chunk to an
1413 * active destination transport address that is
1414 * different from the last destination address to
1415 * which the DATA chunk was sent.
1417 struct sctp_transport *retran_path;
1419 /* Pointer to last transport I have sent on. */
1420 struct sctp_transport *last_sent_to;
1422 /* This is the last transport I have received DATA on. */
1423 struct sctp_transport *last_data_from;
1426 * Mapping An array of bits or bytes indicating which out of
1427 * Array order TSN's have been received (relative to the
1428 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1429 * order packets have been received, this array
1430 * will be set to all zero. This structure may be
1431 * in the form of a circular buffer or bit array.
1433 * Last Rcvd : This is the last TSN received in
1434 * TSN : sequence. This value is set initially by
1435 * : taking the peer's Initial TSN, received in
1436 * : the INIT or INIT ACK chunk, and subtracting
1439 * Throughout most of the specification this is called the
1440 * "Cumulative TSN ACK Point". In this case, we
1441 * ignore the advice in 12.2 in favour of the term
1442 * used in the bulk of the text. This value is hidden
1443 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1445 struct sctp_tsnmap tsn_map;
1446 __u8 _map[sctp_tsnmap_storage_size(SCTP_TSN_MAP_SIZE)];
1448 /* Ack State : This flag indicates if the next received
1449 * : packet is to be responded to with a
1450 * : SACK. This is initializedto 0. When a packet
1451 * : is received it is incremented. If this value
1452 * : reaches 2 or more, a SACK is sent and the
1453 * : value is reset to 0. Note: This is used only
1454 * : when no DATA chunks are received out of
1455 * : order. When DATA chunks are out of order,
1456 * : SACK's are not delayed (see Section 6).
1458 __u8 sack_needed; /* Do we need to sack the peer? */
1460 /* These are capabilities which our peer advertised. */
1461 __u8 ecn_capable; /* Can peer do ECN? */
1462 __u8 ipv4_address; /* Peer understands IPv4 addresses? */
1463 __u8 ipv6_address; /* Peer understands IPv6 addresses? */
1464 __u8 hostname_address;/* Peer understands DNS addresses? */
1465 __u8 asconf_capable; /* Does peer support ADDIP? */
1466 __u8 prsctp_capable; /* Can peer do PR-SCTP? */
1468 __u32 adaption_ind; /* Adaption Code point. */
1470 /* This mask is used to disable sending the ASCONF chunk
1471 * with specified parameter to peer.
1473 __u16 addip_disabled_mask;
1475 struct sctp_inithdr i;
1479 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1480 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1481 * Initial TSN Value minus 1
1486 /* State : A state variable indicating what state the
1487 * : association is in, i.e. COOKIE-WAIT,
1488 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1489 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1491 * Note: No "CLOSED" state is illustrated since if a
1492 * association is "CLOSED" its TCB SHOULD be removed.
1494 * In this implementation we DO have a CLOSED
1495 * state which is used during initiation and shutdown.
1497 * State takes values from SCTP_STATE_*.
1501 /* The cookie life I award for any cookie. */
1502 struct timeval cookie_life;
1504 /* Overall : The overall association error count.
1505 * Error Count : [Clear this any time I get something.]
1507 int overall_error_count;
1509 /* These are the association's initial, max, and min RTO values.
1510 * These values will be initialized by system defaults, but can
1511 * be modified via the SCTP_RTOINFO socket option.
1513 unsigned long rto_initial;
1514 unsigned long rto_max;
1515 unsigned long rto_min;
1517 /* Maximum number of new data packets that can be sent in a burst. */
1520 /* This is the max_retrans value for the association. This value will
1521 * be initialized initialized from system defaults, but can be
1522 * modified by the SCTP_ASSOCINFO socket option.
1526 /* Maximum number of times the endpoint will retransmit INIT */
1527 __u16 max_init_attempts;
1529 /* How many times have we resent an INIT? */
1532 /* The largest timeout or RTO value to use in attempting an INIT */
1533 unsigned long max_init_timeo;
1535 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1536 * the destination address every heartbeat interval. This value
1537 * will be inherited by all new transports.
1539 unsigned long hbinterval;
1541 /* This is the max_retrans value for new transports in the
1546 /* Association : The smallest PMTU discovered for all of the
1547 * PMTU : peer's transport addresses.
1551 /* Flags controling Heartbeat, SACK delay, and Path MTU Discovery. */
1554 /* SACK delay timeout */
1555 unsigned long sackdelay;
1558 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES];
1559 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1561 /* Transport to which SHUTDOWN chunk was last sent. */
1562 struct sctp_transport *shutdown_last_sent_to;
1564 /* Transport to which INIT chunk was last sent. */
1565 struct sctp_transport *init_last_sent_to;
1567 /* Next TSN : The next TSN number to be assigned to a new
1568 * : DATA chunk. This is sent in the INIT or INIT
1569 * : ACK chunk to the peer and incremented each
1570 * : time a DATA chunk is assigned a TSN
1571 * : (normally just prior to transmit or during
1577 * Last Rcvd : This is the last TSN received in sequence. This value
1578 * TSN : is set initially by taking the peer's Initial TSN,
1579 * : received in the INIT or INIT ACK chunk, and
1580 * : subtracting one from it.
1582 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1585 __u32 ctsn_ack_point;
1587 /* PR-SCTP Advanced.Peer.Ack.Point */
1588 __u32 adv_peer_ack_point;
1590 /* Highest TSN that is acknowledged by incoming SACKs. */
1591 __u32 highest_sacked;
1593 /* The number of unacknowledged data chunks. Reported through
1594 * the SCTP_STATUS sockopt.
1598 /* This is the association's receive buffer space. This value is used
1599 * to set a_rwnd field in an INIT or a SACK chunk.
1603 /* This is the last advertised value of rwnd over a SACK chunk. */
1606 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1607 * to slop over a maximum of the association's frag_point.
1611 /* This is the sndbuf size in use for the association.
1612 * This corresponds to the sndbuf size for the association,
1613 * as specified in the sk->sndbuf.
1617 /* This is the amount of memory that this association has allocated
1618 * in the receive path at any given time.
1620 atomic_t rmem_alloc;
1622 /* This is the wait queue head for send requests waiting on
1623 * the association sndbuf space.
1625 wait_queue_head_t wait;
1627 /* The message size at which SCTP fragmentation will occur. */
1630 /* Counter used to count INIT errors. */
1631 int init_err_counter;
1633 /* Count the number of INIT cycles (for doubling timeout). */
1636 /* Default send parameters. */
1637 __u16 default_stream;
1638 __u16 default_flags;
1640 __u32 default_context;
1641 __u32 default_timetolive;
1643 /* This tracks outbound ssn for a given stream. */
1644 struct sctp_ssnmap *ssnmap;
1646 /* All outbound chunks go through this structure. */
1647 struct sctp_outq outqueue;
1649 /* A smart pipe that will handle reordering and fragmentation,
1650 * as well as handle passing events up to the ULP.
1652 struct sctp_ulpq ulpq;
1654 /* Last TSN that caused an ECNE Chunk to be sent. */
1655 __u32 last_ecne_tsn;
1657 /* Last TSN that caused a CWR Chunk to be sent. */
1660 /* How many duplicated TSNs have we seen? */
1663 /* Number of seconds of idle time before an association is closed.
1664 * In the association context, this is really used as a boolean
1665 * since the real timeout is stored in the timeouts array
1669 /* These are to support
1670 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1671 * and Enforcement of Flow and Message Limits"
1672 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1673 * or "ADDIP" for short.
1678 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1680 * R1) One and only one ASCONF Chunk MAY be in transit and
1681 * unacknowledged at any one time. If a sender, after sending
1682 * an ASCONF chunk, decides it needs to transfer another
1683 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1684 * returns from the previous ASCONF Chunk before sending a
1685 * subsequent ASCONF. Note this restriction binds each side,
1686 * so at any time two ASCONF may be in-transit on any given
1687 * association (one sent from each endpoint).
1689 * [This is our one-and-only-one ASCONF in flight. If we do
1690 * not have an ASCONF in flight, this is NULL.]
1692 struct sctp_chunk *addip_last_asconf;
1694 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1696 * IMPLEMENTATION NOTE: As an optimization a receiver may wish
1697 * to save the last ASCONF-ACK for some predetermined period
1698 * of time and instead of re-processing the ASCONF (with the
1699 * same serial number) it may just re-transmit the
1700 * ASCONF-ACK. It may wish to use the arrival of a new serial
1701 * number to discard the previously saved ASCONF-ACK or any
1702 * other means it may choose to expire the saved ASCONF-ACK.
1704 * [This is our saved ASCONF-ACK. We invalidate it when a new
1705 * ASCONF serial number arrives.]
1707 struct sctp_chunk *addip_last_asconf_ack;
1709 /* These ASCONF chunks are waiting to be sent.
1711 * These chunaks can't be pushed to outqueue until receiving
1712 * ASCONF_ACK for the previous ASCONF indicated by
1713 * addip_last_asconf, so as to guarantee that only one ASCONF
1714 * is in flight at any time.
1716 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1718 * In defining the ASCONF Chunk transfer procedures, it is
1719 * essential that these transfers MUST NOT cause congestion
1720 * within the network. To achieve this, we place these
1721 * restrictions on the transfer of ASCONF Chunks:
1723 * R1) One and only one ASCONF Chunk MAY be in transit and
1724 * unacknowledged at any one time. If a sender, after sending
1725 * an ASCONF chunk, decides it needs to transfer another
1726 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1727 * returns from the previous ASCONF Chunk before sending a
1728 * subsequent ASCONF. Note this restriction binds each side,
1729 * so at any time two ASCONF may be in-transit on any given
1730 * association (one sent from each endpoint).
1733 * [I really think this is EXACTLY the sort of intelligence
1734 * which already resides in sctp_outq. Please move this
1735 * queue and its supporting logic down there. --piggy]
1737 struct list_head addip_chunk_list;
1739 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1741 * A2) A serial number should be assigned to the Chunk. The
1742 * serial number SHOULD be a monotonically increasing
1743 * number. The serial number SHOULD be initialized at
1744 * the start of the association to the same value as the
1745 * Initial TSN and every time a new ASCONF chunk is created
1746 * it is incremented by one after assigning the serial number
1747 * to the newly created chunk.
1750 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
1752 * Serial Number : 32 bits (unsigned integer)
1754 * This value represents a Serial Number for the ASCONF
1755 * Chunk. The valid range of Serial Number is from 0 to
1756 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
1757 * after reaching 4294967295.
1761 /* Need to send an ECNE Chunk? */
1764 /* Is it a temporary association? */
1769 /* An eyecatcher for determining if we are really looking at an
1770 * association data structure.
1773 SCTP_ASSOC_EYECATCHER = 0xa550c123,
1776 /* Recover the outter association structure. */
1777 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
1779 struct sctp_association *asoc;
1781 asoc = container_of(base, struct sctp_association, base);
1785 /* These are function signatures for manipulating associations. */
1788 struct sctp_association *
1789 sctp_association_new(const struct sctp_endpoint *, const struct sock *,
1790 sctp_scope_t scope, gfp_t gfp);
1791 void sctp_association_free(struct sctp_association *);
1792 void sctp_association_put(struct sctp_association *);
1793 void sctp_association_hold(struct sctp_association *);
1795 struct sctp_transport *sctp_assoc_choose_init_transport(
1796 struct sctp_association *);
1797 struct sctp_transport *sctp_assoc_choose_shutdown_transport(
1798 struct sctp_association *);
1799 void sctp_assoc_update_retran_path(struct sctp_association *);
1800 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
1801 const union sctp_addr *);
1802 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1803 const union sctp_addr *laddr);
1804 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
1805 const union sctp_addr *address,
1807 const int peer_state);
1808 void sctp_assoc_del_peer(struct sctp_association *asoc,
1809 const union sctp_addr *addr);
1810 void sctp_assoc_rm_peer(struct sctp_association *asoc,
1811 struct sctp_transport *peer);
1812 void sctp_assoc_control_transport(struct sctp_association *,
1813 struct sctp_transport *,
1814 sctp_transport_cmd_t, sctp_sn_error_t);
1815 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
1816 struct sctp_transport *sctp_assoc_is_match(struct sctp_association *,
1817 const union sctp_addr *,
1818 const union sctp_addr *);
1819 void sctp_assoc_migrate(struct sctp_association *, struct sock *);
1820 void sctp_assoc_update(struct sctp_association *old,
1821 struct sctp_association *new);
1823 __u32 sctp_association_get_next_tsn(struct sctp_association *);
1825 void sctp_assoc_sync_pmtu(struct sctp_association *);
1826 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned);
1827 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned);
1828 void sctp_assoc_set_primary(struct sctp_association *,
1829 struct sctp_transport *);
1830 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *,
1832 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
1833 struct sctp_cookie*,
1836 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1837 const union sctp_addr *ss2);
1838 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
1840 /* A convenience structure to parse out SCTP specific CMSGs. */
1841 typedef struct sctp_cmsgs {
1842 struct sctp_initmsg *init;
1843 struct sctp_sndrcvinfo *info;
1846 /* Structure for tracking memory objects */
1850 } sctp_dbg_objcnt_entry_t;
1852 #endif /* __sctp_structs_h__ */