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 <asm/param.h> /* We get MAXHOSTNAMELEN. */
62 #include <asm/atomic.h> /* This gets us atomic counters. */
63 #include <linux/skbuff.h> /* We need sk_buff_head. */
64 #include <linux/workqueue.h> /* We need tq_struct. */
65 #include <linux/sctp.h> /* We need sctp* header structs. */
67 /* A convenience structure for handling sockaddr structures.
68 * We should wean ourselves off this.
71 struct sockaddr_in v4;
72 struct sockaddr_in6 v6;
76 /* Forward declarations for data structures. */
79 struct sctp_association;
80 struct sctp_transport;
85 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.)
134 /* Note: rto_alpha and rto_beta are really defined as inverse
135 * powers of two to facilitate integer operations.
143 /* Valid.Cookie.Life - 60 seconds */
144 int valid_cookie_life;
146 /* Whether Cookie Preservative is enabled(1) or not(0) */
147 int cookie_preserve_enable;
149 /* Association.Max.Retrans - 10 attempts
150 * Path.Max.Retrans - 5 attempts (per destination address)
151 * Max.Init.Retransmits - 8 attempts
153 int max_retrans_association;
154 int max_retrans_path;
155 int max_retrans_init;
157 /* HB.interval - 30 seconds */
160 /* The following variables are implementation specific. */
162 /* Default initialization values to be applied to new associations. */
164 __u16 max_outstreams;
166 /* This is a list of groups of functions for each address
167 * family that we support.
169 struct list_head address_families;
171 /* This is the hash of all endpoints. */
173 struct sctp_hashbucket *ep_hashtable;
175 /* This is the hash of all associations. */
177 struct sctp_hashbucket *assoc_hashtable;
179 /* This is the sctp port control hash. */
182 spinlock_t port_alloc_lock; /* Protects port_rover. */
183 struct sctp_bind_hashbucket *port_hashtable;
185 /* This is the global local address list.
186 * We actively maintain this complete list of interfaces on
187 * the system by catching routing events.
189 * It is a list of sctp_sockaddr_entry.
191 struct list_head local_addr_list;
192 spinlock_t local_addr_lock;
194 /* Flag to indicate if addip is enabled. */
197 /* Flag to indicate if PR-SCTP is enabled. */
201 #define sctp_rto_initial (sctp_globals.rto_initial)
202 #define sctp_rto_min (sctp_globals.rto_min)
203 #define sctp_rto_max (sctp_globals.rto_max)
204 #define sctp_rto_alpha (sctp_globals.rto_alpha)
205 #define sctp_rto_beta (sctp_globals.rto_beta)
206 #define sctp_max_burst (sctp_globals.max_burst)
207 #define sctp_valid_cookie_life (sctp_globals.valid_cookie_life)
208 #define sctp_cookie_preserve_enable (sctp_globals.cookie_preserve_enable)
209 #define sctp_max_retrans_association (sctp_globals.max_retrans_association)
210 #define sctp_max_retrans_path (sctp_globals.max_retrans_path)
211 #define sctp_max_retrans_init (sctp_globals.max_retrans_init)
212 #define sctp_hb_interval (sctp_globals.hb_interval)
213 #define sctp_max_instreams (sctp_globals.max_instreams)
214 #define sctp_max_outstreams (sctp_globals.max_outstreams)
215 #define sctp_address_families (sctp_globals.address_families)
216 #define sctp_ep_hashsize (sctp_globals.ep_hashsize)
217 #define sctp_ep_hashtable (sctp_globals.ep_hashtable)
218 #define sctp_assoc_hashsize (sctp_globals.assoc_hashsize)
219 #define sctp_assoc_hashtable (sctp_globals.assoc_hashtable)
220 #define sctp_port_hashsize (sctp_globals.port_hashsize)
221 #define sctp_port_rover (sctp_globals.port_rover)
222 #define sctp_port_alloc_lock (sctp_globals.port_alloc_lock)
223 #define sctp_port_hashtable (sctp_globals.port_hashtable)
224 #define sctp_local_addr_list (sctp_globals.local_addr_list)
225 #define sctp_local_addr_lock (sctp_globals.local_addr_lock)
226 #define sctp_addip_enable (sctp_globals.addip_enable)
227 #define sctp_prsctp_enable (sctp_globals.prsctp_enable)
229 /* SCTP Socket type: UDP or TCP style. */
232 SCTP_SOCKET_UDP_HIGH_BANDWIDTH,
234 } sctp_socket_type_t;
236 /* Per socket SCTP information. */
238 /* What kind of a socket is this? */
239 sctp_socket_type_t type;
241 /* PF_ family specific functions. */
244 /* Access to HMAC transform. */
245 struct crypto_tfm *hmac;
247 /* What is our base endpointer? */
248 struct sctp_endpoint *ep;
250 struct sctp_bind_bucket *bind_hash;
251 /* Various Socket Options. */
252 __u16 default_stream;
255 __u32 default_context;
256 __u32 default_timetolive;
258 struct sctp_initmsg initmsg;
259 struct sctp_rtoinfo rtoinfo;
260 struct sctp_paddrparams paddrparam;
261 struct sctp_event_subscribe subscribe;
262 struct sctp_assocparams assocparams;
266 __u8 disable_fragments;
271 /* Receive to here while partial delivery is in effect. */
272 struct sk_buff_head pd_lobby;
277 /* This is our APPLICATION-SPECIFIC state cookie.
278 * THIS IS NOT DICTATED BY THE SPECIFICATION.
280 /* These are the parts of an association which we send in the cookie.
281 * Most of these are straight out of:
282 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
288 /* My : Tag expected in every inbound packet and sent
289 * Verification: in the INIT or INIT ACK chunk.
294 /* Peer's : Tag expected in every outbound packet except
295 * Verification: in the INIT chunk.
300 /* The rest of these are not from the spec, but really need to
304 /* My Tie Tag : Assist in discovering a restarting association. */
307 /* Peer's Tie Tag: Assist in discovering a restarting association. */
310 /* When does this cookie expire? */
311 struct timeval expiration;
313 /* Number of inbound/outbound streams which are set
314 * and negotiated during the INIT process.
316 __u16 sinit_num_ostreams;
317 __u16 sinit_max_instreams;
319 /* This is the first sequence number I used. */
322 /* This holds the originating address of the INIT packet. */
323 union sctp_addr peer_addr;
329 /* This is a shim for my peer's INIT packet, followed by
330 * a copy of the raw address list of the association.
331 * The length of the raw address list is saved in the
332 * raw_addr_list_len field, which will be used at the time when
333 * the association TCB is re-constructed from the cookie.
335 __u32 raw_addr_list_len;
336 struct sctp_init_chunk peer_init[0];
340 /* The format of our cookie that we send to our peer. */
341 struct sctp_signed_cookie {
342 __u8 signature[SCTP_SECRET_SIZE];
343 struct sctp_cookie c;
346 /* This is another convenience type to allocate memory for address
347 * params for the maximum size and pass such structures around
350 union sctp_addr_param {
351 struct sctp_ipv4addr_param v4;
352 struct sctp_ipv6addr_param v6;
355 /* A convenience type to allow walking through the various
356 * parameters and avoid casting all over the place.
360 struct sctp_paramhdr *p;
361 struct sctp_cookie_preserve_param *life;
362 struct sctp_hostname_param *dns;
363 struct sctp_cookie_param *cookie;
364 struct sctp_supported_addrs_param *sat;
365 struct sctp_ipv4addr_param *v4;
366 struct sctp_ipv6addr_param *v6;
367 union sctp_addr_param *addr;
368 struct sctp_adaption_ind_param *aind;
371 /* RFC 2960. Section 3.3.5 Heartbeat.
372 * Heartbeat Information: variable length
373 * The Sender-specific Heartbeat Info field should normally include
374 * information about the sender's current time when this HEARTBEAT
375 * chunk is sent and the destination transport address to which this
376 * HEARTBEAT is sent (see Section 8.3).
378 typedef struct sctp_sender_hb_info {
379 struct sctp_paramhdr param_hdr;
380 union sctp_addr daddr;
381 unsigned long sent_at;
382 } __attribute__((packed)) sctp_sender_hb_info_t;
385 * RFC 2960 1.3.2 Sequenced Delivery within Streams
387 * The term "stream" is used in SCTP to refer to a sequence of user
388 * messages that are to be delivered to the upper-layer protocol in
389 * order with respect to other messages within the same stream. This is
390 * in contrast to its usage in TCP, where it refers to a sequence of
391 * bytes (in this document a byte is assumed to be eight bits).
394 * This is the structure we use to track both our outbound and inbound
395 * SSN, or Stream Sequence Numbers.
404 struct sctp_stream in;
405 struct sctp_stream out;
409 struct sctp_ssnmap *sctp_ssnmap_init(struct sctp_ssnmap *, __u16, __u16);
410 struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out, int gfp);
411 void sctp_ssnmap_free(struct sctp_ssnmap *map);
412 void sctp_ssnmap_clear(struct sctp_ssnmap *map);
414 /* What is the current SSN number for this stream? */
415 static inline __u16 sctp_ssn_peek(struct sctp_stream *stream, __u16 id)
417 return stream->ssn[id];
420 /* Return the next SSN number for this stream. */
421 static inline __u16 sctp_ssn_next(struct sctp_stream *stream, __u16 id)
423 return stream->ssn[id]++;
426 /* Skip over this ssn and all below. */
427 static inline void sctp_ssn_skip(struct sctp_stream *stream, __u16 id,
430 stream->ssn[id] = ssn+1;
434 * Pointers to address related SCTP functions.
435 * (i.e. things that depend on the address family.)
438 int (*sctp_xmit) (struct sk_buff *skb,
439 struct sctp_transport *,
441 int (*setsockopt) (struct sock *sk,
446 int (*getsockopt) (struct sock *sk,
451 struct dst_entry *(*get_dst) (struct sctp_association *asoc,
452 union sctp_addr *daddr,
453 union sctp_addr *saddr);
454 void (*get_saddr) (struct sctp_association *asoc,
455 struct dst_entry *dst,
456 union sctp_addr *daddr,
457 union sctp_addr *saddr);
458 void (*copy_addrlist) (struct list_head *,
459 struct net_device *);
460 void (*dst_saddr) (union sctp_addr *saddr,
461 struct dst_entry *dst,
462 unsigned short port);
463 int (*cmp_addr) (const union sctp_addr *addr1,
464 const union sctp_addr *addr2);
465 void (*addr_copy) (union sctp_addr *dst,
466 union sctp_addr *src);
467 void (*from_skb) (union sctp_addr *,
470 void (*from_sk) (union sctp_addr *,
472 void (*to_sk_saddr) (union sctp_addr *,
474 void (*to_sk_daddr) (union sctp_addr *,
476 void (*from_addr_param) (union sctp_addr *,
477 union sctp_addr_param *,
478 __u16 port, int iif);
479 int (*to_addr_param) (const union sctp_addr *,
480 union sctp_addr_param *);
481 int (*addr_valid) (union sctp_addr *,
483 sctp_scope_t (*scope) (union sctp_addr *);
484 void (*inaddr_any) (union sctp_addr *, unsigned short);
485 int (*is_any) (const union sctp_addr *);
486 int (*available) (union sctp_addr *,
488 int (*skb_iif) (const struct sk_buff *sk);
489 int (*is_ce) (const struct sk_buff *sk);
490 void (*seq_dump_addr)(struct seq_file *seq,
491 union sctp_addr *addr);
492 __u16 net_header_len;
494 sa_family_t sa_family;
495 struct list_head list;
498 struct sctp_af *sctp_get_af_specific(sa_family_t);
499 int sctp_register_af(struct sctp_af *);
501 /* Protocol family functions. */
503 void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
504 void (*skb_msgname) (struct sk_buff *, char *, int *);
505 int (*af_supported) (sa_family_t, struct sctp_opt *);
506 int (*cmp_addr) (const union sctp_addr *,
507 const union sctp_addr *,
509 int (*bind_verify) (struct sctp_opt *, union sctp_addr *);
510 int (*send_verify) (struct sctp_opt *, union sctp_addr *);
511 int (*supported_addrs)(const struct sctp_opt *, __u16 *);
512 struct sock *(*create_accept_sk) (struct sock *sk,
513 struct sctp_association *asoc);
514 void (*addr_v4map) (struct sctp_opt *, union sctp_addr *);
519 /* Structure to track chunk fragments that have been acked, but peer
520 * fragments of the same message have not.
522 struct sctp_datamsg {
523 /* Chunks waiting to be submitted to lower layer. */
524 struct list_head chunks;
525 /* Chunks that have been transmitted. */
526 struct list_head track;
527 /* Reference counting. */
529 /* When is this message no longer interesting to the peer? */
530 unsigned long expires_at;
531 /* Did the messenge fail to send? */
534 /* Control whether chunks from this message can be abandoned. */
538 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
539 struct sctp_sndrcvinfo *,
540 struct msghdr *, int len);
541 struct sctp_datamsg *sctp_datamsg_new(int gfp);
542 void sctp_datamsg_put(struct sctp_datamsg *);
543 void sctp_datamsg_hold(struct sctp_datamsg *);
544 void sctp_datamsg_free(struct sctp_datamsg *);
545 void sctp_datamsg_track(struct sctp_chunk *);
546 void sctp_datamsg_assign(struct sctp_datamsg *, struct sctp_chunk *);
547 void sctp_chunk_fail(struct sctp_chunk *, int error);
548 int sctp_chunk_abandoned(struct sctp_chunk *);
551 /* RFC2960 1.4 Key Terms
553 * o Chunk: A unit of information within an SCTP packet, consisting of
554 * a chunk header and chunk-specific content.
556 * As a matter of convenience, we remember the SCTP common header for
557 * each chunk as well as a few other header pointers...
560 /* These first three elements MUST PRECISELY match the first
561 * three elements of struct sk_buff. This allows us to reuse
562 * all the skb_* queue management functions.
564 struct sctp_chunk *next;
565 struct sctp_chunk *prev;
566 struct sk_buff_head *list;
569 /* This is our link to the per-transport transmitted list. */
570 struct list_head transmitted_list;
572 /* This field is used by chunks that hold fragmented data.
573 * For the first fragment this is the list that holds the rest of
574 * fragments. For the remaining fragments, this is the link to the
575 * frag_list maintained in the first fragment.
577 struct list_head frag_list;
579 /* This points to the sk_buff containing the actual data. */
582 /* These are the SCTP headers by reverse order in a packet.
583 * Note that some of these may happen more than once. In that
584 * case, we point at the "current" one, whatever that means
585 * for that level of header.
588 /* We point this at the FIRST TLV parameter to chunk_hdr. */
589 union sctp_params param_hdr;
592 struct sctp_datahdr *data_hdr;
593 struct sctp_inithdr *init_hdr;
594 struct sctp_sackhdr *sack_hdr;
595 struct sctp_heartbeathdr *hb_hdr;
596 struct sctp_sender_hb_info *hbs_hdr;
597 struct sctp_shutdownhdr *shutdown_hdr;
598 struct sctp_signed_cookie *cookie_hdr;
599 struct sctp_ecnehdr *ecne_hdr;
600 struct sctp_cwrhdr *ecn_cwr_hdr;
601 struct sctp_errhdr *err_hdr;
602 struct sctp_addiphdr *addip_hdr;
603 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
608 struct sctp_chunkhdr *chunk_hdr;
609 struct sctphdr *sctp_hdr;
611 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
612 struct sctp_sndrcvinfo sinfo;
614 /* Which association does this belong to? */
615 struct sctp_association *asoc;
617 /* What endpoint received this chunk? */
618 struct sctp_ep_common *rcvr;
620 /* We fill this in if we are calculating RTT. */
621 unsigned long sent_at;
623 /* What is the origin IP address for this chunk? */
624 union sctp_addr source;
625 /* Destination address for this chunk. */
626 union sctp_addr dest;
628 /* For outbound message, track all fragments for SEND_FAILED. */
629 struct sctp_datamsg *msg;
631 /* For an inbound chunk, this tells us where it came from.
632 * For an outbound chunk, it tells us where we'd like it to
633 * go. It is NULL if we have no preference.
635 struct sctp_transport *transport;
637 __u8 rtt_in_progress; /* Is this chunk used for RTT calculation? */
638 __u8 resent; /* Has this chunk ever been retransmitted. */
639 __u8 has_tsn; /* Does this chunk have a TSN yet? */
640 __u8 has_ssn; /* Does this chunk have a SSN yet? */
641 __u8 singleton; /* Was this the only chunk in the packet? */
642 __u8 end_of_packet; /* Was this the last chunk in the packet? */
643 __u8 ecn_ce_done; /* Have we processed the ECN CE bit? */
644 __u8 pdiscard; /* Discard the whole packet now? */
645 __u8 tsn_gap_acked; /* Is this chunk acked by a GAP ACK? */
646 __u8 fast_retransmit; /* Is this chunk fast retransmitted? */
647 __u8 tsn_missing_report; /* Data chunk missing counter. */
650 void sctp_chunk_hold(struct sctp_chunk *);
651 void sctp_chunk_put(struct sctp_chunk *);
652 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
654 struct sctp_chunk *sctp_make_chunk(const struct sctp_association *, __u8 type,
655 __u8 flags, int size);
656 void sctp_chunk_free(struct sctp_chunk *);
657 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
658 struct sctp_chunk *sctp_chunkify(struct sk_buff *,
659 const struct sctp_association *,
661 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
663 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
665 /* This is a structure for holding either an IPv6 or an IPv4 address. */
666 /* sin_family -- AF_INET or AF_INET6
667 * sin_port -- ordinary port number
668 * sin_addr -- cast to either (struct in_addr) or (struct in6_addr)
670 struct sctp_sockaddr_entry {
671 struct list_head list;
675 typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *);
677 /* This structure holds lists of chunks as we are assembling for
681 /* These are the SCTP header values (host order) for the packet. */
683 __u16 destination_port;
686 /* This contains the payload chunks. */
687 struct sk_buff_head chunks;
689 /* This is the overhead of the sctp and ip headers. */
691 /* This is the total size of all chunks INCLUDING padding. */
694 /* The packet is destined for this transport address.
695 * The function we finally use to pass down to the next lower
696 * layer lives in the transport structure.
698 struct sctp_transport *transport;
700 /* This packet contains a COOKIE-ECHO chunk. */
701 char has_cookie_echo;
703 /* This packet containsa SACK chunk. */
706 /* SCTP cannot fragment this packet. So let ip fragment it. */
712 struct sctp_packet *sctp_packet_init(struct sctp_packet *,
713 struct sctp_transport *,
714 __u16 sport, __u16 dport);
715 struct sctp_packet *sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
716 sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *,
717 struct sctp_chunk *);
718 sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *,
719 struct sctp_chunk *);
720 int sctp_packet_transmit(struct sctp_packet *);
721 void sctp_packet_free(struct sctp_packet *);
723 static inline int sctp_packet_empty(struct sctp_packet *packet)
725 return (packet->size == packet->overhead);
728 /* This represents a remote transport address.
729 * For local transport addresses, we just use union sctp_addr.
731 * RFC2960 Section 1.4 Key Terms
733 * o Transport address: A Transport Address is traditionally defined
734 * by Network Layer address, Transport Layer protocol and Transport
735 * Layer port number. In the case of SCTP running over IP, a
736 * transport address is defined by the combination of an IP address
737 * and an SCTP port number (where SCTP is the Transport protocol).
739 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
741 * o The sender keeps a separate congestion control parameter set for
742 * each of the destination addresses it can send to (not each
743 * source-destination pair but for each destination). The parameters
744 * should decay if the address is not used for a long enough time
748 struct sctp_transport {
749 /* A list of transports. */
750 struct list_head transports;
752 /* Reference counting. */
756 /* This is the peer's IP address and port. */
757 union sctp_addr ipaddr;
759 /* These are the functions we call to handle LLP stuff. */
760 struct sctp_af *af_specific;
762 /* Which association do we belong to? */
763 struct sctp_association *asoc;
767 * 12.3 Per Transport Address Data
769 * For each destination transport address in the peer's
770 * address list derived from the INIT or INIT ACK chunk, a
771 * number of data elements needs to be maintained including:
773 __u32 rtt; /* This is the most recent RTT. */
775 /* RTO : The current retransmission timeout value. */
778 /* RTTVAR : The current RTT variation. */
781 /* SRTT : The current smoothed round trip time. */
784 /* RTO-Pending : A flag used to track if one of the DATA
785 * chunks sent to this address is currently being
786 * used to compute a RTT. If this flag is 0,
787 * the next DATA chunk sent to this destination
788 * should be used to compute a RTT and this flag
789 * should be set. Every time the RTT
790 * calculation completes (i.e. the DATA chunk
791 * is SACK'd) clear this flag.
796 * These are the congestion stats.
798 /* cwnd : The current congestion window. */
799 __u32 cwnd; /* This is the actual cwnd. */
801 /* ssthresh : The current slow start threshold value. */
804 /* partial : The tracking method for increase of cwnd when in
805 * bytes acked : congestion avoidance mode (see Section 6.2.2)
807 __u32 partial_bytes_acked;
809 /* Data that has been sent, but not acknowledged. */
812 /* PMTU : The current known path MTU. */
816 struct dst_entry *dst;
817 /* Source address. */
818 union sctp_addr saddr;
820 /* When was the last time(in jiffies) that a data packet was sent on
821 * this transport? This is used to adjust the cwnd when the transport
824 unsigned long last_time_used;
826 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
827 * the destination address every heartbeat interval.
831 /* When was the last time (in jiffies) that we heard from this
832 * transport? We use this to pick new active and retran paths.
834 unsigned long last_time_heard;
836 /* Last time(in jiffies) when cwnd is reduced due to the congestion
837 * indication based on ECNE chunk.
839 unsigned long last_time_ecne_reduced;
841 /* active : The current active state of this destination,
842 * : i.e. DOWN, UP, etc.
846 /* hb_allowed : The current heartbeat state of this destination,
847 * : i.e. ALLOW-HB, NO-HEARTBEAT, etc.
851 /* These are the error stats for this destination. */
853 /* Error count : The current error count for this destination. */
854 unsigned short error_count;
856 /* Error : Current error threshold for this destination
857 * Threshold : i.e. what value marks the destination down if
858 * : errorCount reaches this value.
860 unsigned short error_threshold;
862 /* This is the max_retrans value for the transport and will
863 * be initialized to proto.max_retrans.path. This can be changed
864 * using SCTP_SET_PEER_ADDR_PARAMS socket option.
868 /* Per : A timer used by each destination.
872 * [Everywhere else in the text this is called T3-rtx. -ed]
874 struct timer_list T3_rtx_timer;
876 /* Heartbeat timer is per destination. */
877 struct timer_list hb_timer;
879 /* Since we're using per-destination retransmission timers
880 * (see above), we're also using per-destination "transmitted"
881 * queues. This probably ought to be a private struct
882 * accessible only within the outqueue, but it's not, yet.
884 struct list_head transmitted;
886 /* We build bundle-able packets for this transport here. */
887 struct sctp_packet packet;
889 /* This is the list of transports that have chunks to send. */
890 struct list_head send_ready;
892 int malloced; /* Is this structure kfree()able? */
894 /* State information saved for SFR_CACC algorithm. The key
895 * idea in SFR_CACC is to maintain state at the sender on a
896 * per-destination basis when a changeover happens.
897 * char changeover_active;
898 * char cycling_changeover;
899 * __u32 next_tsn_at_change;
900 * char cacc_saw_newack;
903 /* An unsigned integer, which stores the next TSN to be
904 * used by the sender, at the moment of changeover.
906 __u32 next_tsn_at_change;
908 /* A flag which indicates the occurrence of a changeover */
909 char changeover_active;
911 /* A flag which indicates whether the change of primary is
912 * the first switch to this destination address during an
915 char cycling_changeover;
917 /* A temporary flag, which is used during the processing of
918 * a SACK to estimate the causative TSN(s)'s group.
920 char cacc_saw_newack;
924 struct sctp_transport *sctp_transport_new(const union sctp_addr *, int);
925 struct sctp_transport *sctp_transport_init(struct sctp_transport *,
926 const union sctp_addr *, int);
927 void sctp_transport_set_owner(struct sctp_transport *,
928 struct sctp_association *);
929 void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
931 void sctp_transport_pmtu(struct sctp_transport *);
932 void sctp_transport_free(struct sctp_transport *);
933 void sctp_transport_destroy(struct sctp_transport *);
934 void sctp_transport_reset_timers(struct sctp_transport *);
935 void sctp_transport_hold(struct sctp_transport *);
936 void sctp_transport_put(struct sctp_transport *);
937 void sctp_transport_update_rto(struct sctp_transport *, __u32);
938 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
939 void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t);
940 unsigned long sctp_transport_timeout(struct sctp_transport *);
943 /* This is the structure we use to queue packets as they come into
944 * SCTP. We write packets to it and read chunks from it.
947 /* This is actually a queue of sctp_chunk each
948 * containing a partially decoded packet.
950 struct sk_buff_head in;
951 /* This is the packet which is currently off the in queue and is
952 * being worked on through the inbound chunk processing.
954 struct sctp_chunk *in_progress;
956 /* This is the delayed task to finish delivering inbound
959 struct work_struct immediate;
961 int malloced; /* Is this structure kfree()able? */
964 struct sctp_inq *sctp_inq_new(void);
965 void sctp_inq_init(struct sctp_inq *);
966 void sctp_inq_free(struct sctp_inq *);
967 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
968 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
969 void sctp_inq_set_th_handler(struct sctp_inq *, void (*)(void *), void *);
971 /* This is the structure we use to hold outbound chunks. You push
972 * chunks in and they automatically pop out the other end as bundled
973 * packets (it calls (*output_handler)()).
975 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
976 * and 8.2 of the v13 draft.
978 * It handles retransmissions. The connection to the timeout portion
979 * of the state machine is through sctp_..._timeout() and timeout_handler.
981 * If you feed it SACKs, it will eat them.
983 * If you give it big chunks, it will fragment them.
985 * It assigns TSN's to data chunks. This happens at the last possible
986 * instant before transmission.
988 * When free()'d, it empties itself out via output_handler().
991 struct sctp_association *asoc;
993 /* Data pending that has never been transmitted. */
994 struct sk_buff_head out;
996 unsigned out_qlen; /* Total length of queued data chunks. */
998 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1001 /* These are control chunks we want to send. */
1002 struct sk_buff_head control;
1004 /* These are chunks that have been sacked but are above the
1005 * CTSN, or cumulative tsn ack point.
1007 struct list_head sacked;
1009 /* Put chunks on this list to schedule them for
1012 struct list_head retransmit;
1014 /* Put chunks on this list to save them for FWD TSN processing as
1015 * they were abandoned.
1017 struct list_head abandoned;
1019 /* How many unackd bytes do we have in-flight? */
1020 __u32 outstanding_bytes;
1025 /* Is this structure empty? */
1028 /* Are we kfree()able? */
1032 struct sctp_outq *sctp_outq_new(struct sctp_association *);
1033 void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1034 void sctp_outq_teardown(struct sctp_outq *);
1035 void sctp_outq_free(struct sctp_outq*);
1036 int sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk);
1037 int sctp_outq_flush(struct sctp_outq *, int);
1038 int sctp_outq_sack(struct sctp_outq *, struct sctp_sackhdr *);
1039 int sctp_outq_is_empty(const struct sctp_outq *);
1040 void sctp_outq_restart(struct sctp_outq *);
1042 void sctp_retransmit(struct sctp_outq *, struct sctp_transport *,
1043 sctp_retransmit_reason_t);
1044 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1045 int sctp_outq_uncork(struct sctp_outq *);
1046 /* Uncork and flush an outqueue. */
1047 static inline void sctp_outq_cork(struct sctp_outq *q)
1052 /* These bind address data fields common between endpoints and associations */
1053 struct sctp_bind_addr {
1055 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1057 * SCTP Port: The local SCTP port number the endpoint is
1062 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1064 * Address List: The list of IP addresses that this instance
1065 * has bound. This information is passed to one's
1066 * peer(s) in INIT and INIT ACK chunks.
1068 struct list_head address_list;
1070 int malloced; /* Are we kfree()able? */
1073 struct sctp_bind_addr *sctp_bind_addr_new(int gfp_mask);
1074 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1075 void sctp_bind_addr_free(struct sctp_bind_addr *);
1076 int sctp_bind_addr_copy(struct sctp_bind_addr *dest,
1077 const struct sctp_bind_addr *src,
1078 sctp_scope_t scope, int gfp,int flags);
1079 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1081 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1082 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1084 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp,
1085 const union sctp_addr *addrs,
1087 struct sctp_opt *opt);
1088 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1089 int *addrs_len, int gfp);
1090 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1091 __u16 port, int gfp);
1093 sctp_scope_t sctp_scope(const union sctp_addr *);
1094 int sctp_in_scope(const union sctp_addr *addr, const sctp_scope_t scope);
1095 int sctp_is_any(const union sctp_addr *addr);
1096 int sctp_addr_is_valid(const union sctp_addr *addr);
1099 /* What type of endpoint? */
1101 SCTP_EP_TYPE_SOCKET,
1102 SCTP_EP_TYPE_ASSOCIATION,
1103 } sctp_endpoint_type_t;
1106 * A common base class to bridge the implmentation view of a
1107 * socket (usually listening) endpoint versus an association's
1109 * This common structure is useful for several purposes:
1110 * 1) Common interface for lookup routines.
1111 * a) Subfunctions work for either endpoint or association
1112 * b) Single interface to lookup allows hiding the lookup lock rather
1113 * than acquiring it externally.
1114 * 2) Common interface for the inbound chunk handling/state machine.
1115 * 3) Common object handling routines for reference counting, etc.
1116 * 4) Disentangle association lookup from endpoint lookup, where we
1117 * do not have to find our endpoint to find our association.
1121 struct sctp_ep_common {
1122 /* Fields to help us manage our entries in the hash tables. */
1123 struct sctp_ep_common *next;
1124 struct sctp_ep_common **pprev;
1127 /* Runtime type information. What kind of endpoint is this? */
1128 sctp_endpoint_type_t type;
1130 /* Some fields to help us manage this object.
1131 * refcnt - Reference count access to this object.
1132 * dead - Do not attempt to use this object.
1133 * malloced - Do we need to kfree this object?
1139 /* What socket does this endpoint belong to? */
1142 /* This is where we receive inbound chunks. */
1143 struct sctp_inq inqueue;
1145 /* This substructure includes the defining parameters of the
1147 * bind_addr.port is our shared port number.
1148 * bind_addr.address_list is our set of local IP addresses.
1150 struct sctp_bind_addr bind_addr;
1152 /* Protection during address list comparisons. */
1157 /* RFC Section 1.4 Key Terms
1159 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1160 * multi-homed host, an SCTP endpoint is represented to its peers as a
1161 * combination of a set of eligible destination transport addresses to
1162 * which SCTP packets can be sent and a set of eligible source
1163 * transport addresses from which SCTP packets can be received.
1164 * All transport addresses used by an SCTP endpoint must use the
1165 * same port number, but can use multiple IP addresses. A transport
1166 * address used by an SCTP endpoint must not be used by another
1167 * SCTP endpoint. In other words, a transport address is unique
1168 * to an SCTP endpoint.
1170 * From an implementation perspective, each socket has one of these.
1171 * A TCP-style socket will have exactly one association on one of
1172 * these. An UDP-style socket will have multiple associations hanging
1176 struct sctp_endpoint {
1177 /* Common substructure for endpoint and association. */
1178 struct sctp_ep_common base;
1180 /* Associations: A list of current associations and mappings
1181 * to the data consumers for each association. This
1182 * may be in the form of a hash table or other
1183 * implementation dependent structure. The data
1184 * consumers may be process identification
1185 * information such as file descriptors, named pipe
1186 * pointer, or table pointers dependent on how SCTP
1189 /* This is really a list of struct sctp_association entries. */
1190 struct list_head asocs;
1192 /* Secret Key: A secret key used by this endpoint to compute
1193 * the MAC. This SHOULD be a cryptographic quality
1194 * random number with a sufficient length.
1195 * Discussion in [RFC1750] can be helpful in
1196 * selection of the key.
1198 __u8 secret_key[SCTP_HOW_MANY_SECRETS][SCTP_SECRET_SIZE];
1203 /* Default timeouts. */
1204 int timeouts[SCTP_NUM_TIMEOUT_TYPES];
1206 /* Various thresholds. */
1208 /* Name for debugging output... */
1212 /* Recover the outter endpoint structure. */
1213 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1215 struct sctp_endpoint *ep;
1217 ep = container_of(base, struct sctp_endpoint, base);
1221 /* These are function signatures for manipulating endpoints. */
1222 struct sctp_endpoint *sctp_endpoint_new(struct sock *, int);
1223 struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *,
1224 struct sock *, int gfp);
1225 void sctp_endpoint_free(struct sctp_endpoint *);
1226 void sctp_endpoint_put(struct sctp_endpoint *);
1227 void sctp_endpoint_hold(struct sctp_endpoint *);
1228 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1229 struct sctp_association *sctp_endpoint_lookup_assoc(
1230 const struct sctp_endpoint *ep,
1231 const union sctp_addr *paddr,
1232 struct sctp_transport **);
1233 int sctp_endpoint_is_peeled_off(struct sctp_endpoint *,
1234 const union sctp_addr *);
1235 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1236 const union sctp_addr *);
1237 int sctp_has_association(const union sctp_addr *laddr,
1238 const union sctp_addr *paddr);
1240 int sctp_verify_init(const struct sctp_association *asoc, sctp_cid_t,
1241 sctp_init_chunk_t *peer_init, struct sctp_chunk *chunk,
1242 struct sctp_chunk **err_chunk);
1243 int sctp_process_init(struct sctp_association *, sctp_cid_t cid,
1244 const union sctp_addr *peer,
1245 sctp_init_chunk_t *init, int gfp);
1246 int sctp_process_param(struct sctp_association *, union sctp_params param,
1247 const union sctp_addr *from, int gfp);
1248 __u32 sctp_generate_tag(const struct sctp_endpoint *);
1249 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
1254 * 12. Recommended Transmission Control Block (TCB) Parameters
1256 * This section details a recommended set of parameters that should
1257 * be contained within the TCB for an implementation. This section is
1258 * for illustrative purposes and should not be deemed as requirements
1259 * on an implementation or as an exhaustive list of all parameters
1260 * inside an SCTP TCB. Each implementation may need its own additional
1261 * parameters for optimization.
1265 /* Here we have information about each individual association. */
1266 struct sctp_association {
1268 /* A base structure common to endpoint and association.
1269 * In this context, it represents the associations's view
1270 * of the local endpoint of the association.
1272 struct sctp_ep_common base;
1274 /* Associations on the same socket. */
1275 struct list_head asocs;
1277 /* association id. */
1278 sctp_assoc_t assoc_id;
1280 /* This is our parent endpoint. */
1281 struct sctp_endpoint *ep;
1283 /* These are those association elements needed in the cookie. */
1284 struct sctp_cookie c;
1286 /* This is all information about our peer. */
1290 * Peer Rwnd : Current calculated value of the peer's rwnd.
1294 /* transport_addr_list
1296 * Peer : A list of SCTP transport addresses that the
1297 * Transport : peer is bound to. This information is derived
1298 * Address : from the INIT or INIT ACK and is used to
1299 * List : associate an inbound packet with a given
1300 * : association. Normally this information is
1301 * : hashed or keyed for quick lookup and access
1304 * It is a list of SCTP_transport's.
1306 struct list_head transport_addr_list;
1309 * The transport layer port number.
1315 * Primary : This is the current primary destination
1316 * Path : transport address of the peer endpoint. It
1317 * : may also specify a source transport address
1318 * : on this endpoint.
1320 * All of these paths live on transport_addr_list.
1322 * At the bakeoffs, we discovered that the intent of
1323 * primaryPath is that it only changes when the ULP
1324 * asks to have it changed. We add the activePath to
1325 * designate the connection we are currently using to
1326 * transmit new data and most control chunks.
1328 struct sctp_transport *primary_path;
1330 /* Cache the primary path address here, when we
1331 * need a an address for msg_name.
1333 union sctp_addr primary_addr;
1336 * The path that we are currently using to
1337 * transmit new data and most control chunks.
1339 struct sctp_transport *active_path;
1343 * RFC2960 6.4 Multi-homed SCTP Endpoints
1345 * Furthermore, when its peer is multi-homed, an
1346 * endpoint SHOULD try to retransmit a chunk to an
1347 * active destination transport address that is
1348 * different from the last destination address to
1349 * which the DATA chunk was sent.
1351 struct sctp_transport *retran_path;
1353 /* Pointer to last transport I have sent on. */
1354 struct sctp_transport *last_sent_to;
1356 /* This is the last transport I have received DATA on. */
1357 struct sctp_transport *last_data_from;
1360 * Mapping An array of bits or bytes indicating which out of
1361 * Array order TSN's have been received (relative to the
1362 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1363 * order packets have been received, this array
1364 * will be set to all zero. This structure may be
1365 * in the form of a circular buffer or bit array.
1367 * Last Rcvd : This is the last TSN received in
1368 * TSN : sequence. This value is set initially by
1369 * : taking the peer's Initial TSN, received in
1370 * : the INIT or INIT ACK chunk, and subtracting
1373 * Throughout most of the specification this is called the
1374 * "Cumulative TSN ACK Point". In this case, we
1375 * ignore the advice in 12.2 in favour of the term
1376 * used in the bulk of the text. This value is hidden
1377 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1379 struct sctp_tsnmap tsn_map;
1380 __u8 _map[sctp_tsnmap_storage_size(SCTP_TSN_MAP_SIZE)];
1382 /* Ack State : This flag indicates if the next received
1383 * : packet is to be responded to with a
1384 * : SACK. This is initializedto 0. When a packet
1385 * : is received it is incremented. If this value
1386 * : reaches 2 or more, a SACK is sent and the
1387 * : value is reset to 0. Note: This is used only
1388 * : when no DATA chunks are received out of
1389 * : order. When DATA chunks are out of order,
1390 * : SACK's are not delayed (see Section 6).
1392 __u8 sack_needed; /* Do we need to sack the peer? */
1394 /* These are capabilities which our peer advertised. */
1395 __u8 ecn_capable; /* Can peer do ECN? */
1396 __u8 ipv4_address; /* Peer understands IPv4 addresses? */
1397 __u8 ipv6_address; /* Peer understands IPv6 addresses? */
1398 __u8 hostname_address;/* Peer understands DNS addresses? */
1399 __u8 asconf_capable; /* Does peer support ADDIP? */
1400 __u8 prsctp_capable; /* Can peer do PR-SCTP? */
1402 __u32 adaption_ind; /* Adaption Code point. */
1404 /* This mask is used to disable sending the ASCONF chunk
1405 * with specified parameter to peer.
1407 __u16 addip_disabled_mask;
1409 struct sctp_inithdr i;
1413 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1414 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1415 * Initial TSN Value minus 1
1420 /* State : A state variable indicating what state the
1421 * : association is in, i.e. COOKIE-WAIT,
1422 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1423 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1425 * Note: No "CLOSED" state is illustrated since if a
1426 * association is "CLOSED" its TCB SHOULD be removed.
1428 * In this implementation we DO have a CLOSED
1429 * state which is used during initiation and shutdown.
1431 * State takes values from SCTP_STATE_*.
1435 /* The cookie life I award for any cookie. */
1436 struct timeval cookie_life;
1438 /* Overall : The overall association error count.
1439 * Error Count : [Clear this any time I get something.]
1441 int overall_error_count;
1443 /* These are the association's initial, max, and min RTO values.
1444 * These values will be initialized by system defaults, but can
1445 * be modified via the SCTP_RTOINFO socket option.
1451 /* Maximum number of new data packets that can be sent in a burst. */
1454 /* This is the max_retrans value for the association. This value will
1455 * be initialized initialized from system defaults, but can be
1456 * modified by the SCTP_ASSOCINFO socket option.
1460 /* Maximum number of times the endpoint will retransmit INIT */
1461 __u16 max_init_attempts;
1463 /* How many times have we resent an INIT? */
1466 /* The largest timeout or RTO value to use in attempting an INIT */
1467 __u16 max_init_timeo;
1469 int timeouts[SCTP_NUM_TIMEOUT_TYPES];
1470 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1472 /* Transport to which SHUTDOWN chunk was last sent. */
1473 struct sctp_transport *shutdown_last_sent_to;
1475 /* Next TSN : The next TSN number to be assigned to a new
1476 * : DATA chunk. This is sent in the INIT or INIT
1477 * : ACK chunk to the peer and incremented each
1478 * : time a DATA chunk is assigned a TSN
1479 * : (normally just prior to transmit or during
1485 * Last Rcvd : This is the last TSN received in sequence. This value
1486 * TSN : is set initially by taking the peer's Initial TSN,
1487 * : received in the INIT or INIT ACK chunk, and
1488 * : subtracting one from it.
1490 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1493 __u32 ctsn_ack_point;
1495 /* PR-SCTP Advanced.Peer.Ack.Point */
1496 __u32 adv_peer_ack_point;
1498 /* Highest TSN that is acknowledged by incoming SACKs. */
1499 __u32 highest_sacked;
1501 /* The number of unacknowledged data chunks. Reported through
1502 * the SCTP_STATUS sockopt.
1506 /* This is the association's receive buffer space. This value is used
1507 * to set a_rwnd field in an INIT or a SACK chunk.
1511 /* This is the last advertised value of rwnd over a SACK chunk. */
1514 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1515 * to slop over a maximum of the association's frag_point.
1519 /* This is the sndbuf size in use for the association.
1520 * This corresponds to the sndbuf size for the association,
1521 * as specified in the sk->sndbuf.
1525 /* This is the wait queue head for send requests waiting on
1526 * the association sndbuf space.
1528 wait_queue_head_t wait;
1530 /* Association : The smallest PMTU discovered for all of the
1531 * PMTU : peer's transport addresses.
1535 /* The message size at which SCTP fragmentation will occur. */
1538 /* Currently only one counter is used to count INIT errors. */
1539 int counters[SCTP_NUMBER_COUNTERS];
1541 /* Default send parameters. */
1542 __u16 default_stream;
1543 __u16 default_flags;
1545 __u32 default_context;
1546 __u32 default_timetolive;
1548 /* This tracks outbound ssn for a given stream. */
1549 struct sctp_ssnmap *ssnmap;
1551 /* All outbound chunks go through this structure. */
1552 struct sctp_outq outqueue;
1554 /* A smart pipe that will handle reordering and fragmentation,
1555 * as well as handle passing events up to the ULP.
1557 struct sctp_ulpq ulpq;
1559 /* Last TSN that caused an ECNE Chunk to be sent. */
1560 __u32 last_ecne_tsn;
1562 /* Last TSN that caused a CWR Chunk to be sent. */
1565 /* How many duplicated TSNs have we seen? */
1568 /* Number of seconds of idle time before an association is closed. */
1571 /* These are to support
1572 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1573 * and Enforcement of Flow and Message Limits"
1574 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1575 * or "ADDIP" for short.
1580 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1582 * R1) One and only one ASCONF Chunk MAY be in transit and
1583 * unacknowledged at any one time. If a sender, after sending
1584 * an ASCONF chunk, decides it needs to transfer another
1585 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1586 * returns from the previous ASCONF Chunk before sending a
1587 * subsequent ASCONF. Note this restriction binds each side,
1588 * so at any time two ASCONF may be in-transit on any given
1589 * association (one sent from each endpoint).
1591 * [This is our one-and-only-one ASCONF in flight. If we do
1592 * not have an ASCONF in flight, this is NULL.]
1594 struct sctp_chunk *addip_last_asconf;
1596 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1598 * IMPLEMENTATION NOTE: As an optimization a receiver may wish
1599 * to save the last ASCONF-ACK for some predetermined period
1600 * of time and instead of re-processing the ASCONF (with the
1601 * same serial number) it may just re-transmit the
1602 * ASCONF-ACK. It may wish to use the arrival of a new serial
1603 * number to discard the previously saved ASCONF-ACK or any
1604 * other means it may choose to expire the saved ASCONF-ACK.
1606 * [This is our saved ASCONF-ACK. We invalidate it when a new
1607 * ASCONF serial number arrives.]
1609 struct sctp_chunk *addip_last_asconf_ack;
1611 /* These ASCONF chunks are waiting to be sent.
1613 * These chunaks can't be pushed to outqueue until receiving
1614 * ASCONF_ACK for the previous ASCONF indicated by
1615 * addip_last_asconf, so as to guarantee that only one ASCONF
1616 * is in flight at any time.
1618 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1620 * In defining the ASCONF Chunk transfer procedures, it is
1621 * essential that these transfers MUST NOT cause congestion
1622 * within the network. To achieve this, we place these
1623 * restrictions on the transfer of ASCONF Chunks:
1625 * R1) One and only one ASCONF Chunk MAY be in transit and
1626 * unacknowledged at any one time. If a sender, after sending
1627 * an ASCONF chunk, decides it needs to transfer another
1628 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1629 * returns from the previous ASCONF Chunk before sending a
1630 * subsequent ASCONF. Note this restriction binds each side,
1631 * so at any time two ASCONF may be in-transit on any given
1632 * association (one sent from each endpoint).
1635 * [I really think this is EXACTLY the sort of intelligence
1636 * which already resides in sctp_outq. Please move this
1637 * queue and its supporting logic down there. --piggy]
1639 struct sk_buff_head addip_chunks;
1641 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1643 * A2) A serial number should be assigned to the Chunk. The
1644 * serial number SHOULD be a monotonically increasing
1645 * number. The serial number SHOULD be initialized at
1646 * the start of the association to the same value as the
1647 * Initial TSN and every time a new ASCONF chunk is created
1648 * it is incremented by one after assigning the serial number
1649 * to the newly created chunk.
1652 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
1654 * Serial Number : 32 bits (unsigned integer)
1656 * This value represents a Serial Number for the ASCONF
1657 * Chunk. The valid range of Serial Number is from 0 to
1658 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
1659 * after reaching 4294967295.
1663 /* Need to send an ECNE Chunk? */
1666 /* Is it a temporary association? */
1671 /* An eyecatcher for determining if we are really looking at an
1672 * association data structure.
1675 SCTP_ASSOC_EYECATCHER = 0xa550c123,
1678 /* Recover the outter association structure. */
1679 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
1681 struct sctp_association *asoc;
1683 asoc = container_of(base, struct sctp_association, base);
1687 /* These are function signatures for manipulating associations. */
1690 struct sctp_association *
1691 sctp_association_new(const struct sctp_endpoint *, const struct sock *,
1692 sctp_scope_t scope, int gfp);
1693 struct sctp_association *
1694 sctp_association_init(struct sctp_association *, const struct sctp_endpoint *,
1695 const struct sock *, sctp_scope_t scope,
1697 void sctp_association_free(struct sctp_association *);
1698 void sctp_association_put(struct sctp_association *);
1699 void sctp_association_hold(struct sctp_association *);
1701 struct sctp_transport *sctp_assoc_choose_shutdown_transport(
1702 struct sctp_association *);
1703 void sctp_assoc_update_retran_path(struct sctp_association *);
1704 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
1705 const union sctp_addr *);
1706 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1707 const union sctp_addr *laddr);
1708 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
1709 const union sctp_addr *address,
1711 void sctp_assoc_del_peer(struct sctp_association *asoc,
1712 const union sctp_addr *addr);
1713 void sctp_assoc_control_transport(struct sctp_association *,
1714 struct sctp_transport *,
1715 sctp_transport_cmd_t, sctp_sn_error_t);
1716 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
1717 struct sctp_transport *sctp_assoc_is_match(struct sctp_association *,
1718 const union sctp_addr *,
1719 const union sctp_addr *);
1720 void sctp_assoc_migrate(struct sctp_association *, struct sock *);
1721 void sctp_assoc_update(struct sctp_association *old,
1722 struct sctp_association *new);
1724 __u32 sctp_association_get_next_tsn(struct sctp_association *);
1725 __u32 sctp_association_get_tsn_block(struct sctp_association *, int);
1727 void sctp_assoc_sync_pmtu(struct sctp_association *);
1728 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned);
1729 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned);
1730 void sctp_assoc_set_primary(struct sctp_association *,
1731 struct sctp_transport *);
1732 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *, int);
1733 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
1734 struct sctp_cookie*, int gfp);
1736 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1737 const union sctp_addr *ss2);
1738 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
1739 struct sctp_chunk *sctp_get_no_prepend(struct sctp_association *asoc);
1741 /* A convenience structure to parse out SCTP specific CMSGs. */
1742 typedef struct sctp_cmsgs {
1743 struct sctp_initmsg *init;
1744 struct sctp_sndrcvinfo *info;
1747 /* Structure for tracking memory objects */
1751 } sctp_dbg_objcnt_entry_t;
1753 #endif /* __sctp_structs_h__ */