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.)
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;
158 * Policy for preforming sctp/socket accounting
159 * 0 - do socket level accounting, all assocs share sk_sndbuf
160 * 1 - do sctp accounting, each asoc may use sk_sndbuf bytes
164 /* Delayed SACK timeout 200ms default*/
167 /* HB.interval - 30 seconds */
170 /* The following variables are implementation specific. */
172 /* Default initialization values to be applied to new associations. */
174 __u16 max_outstreams;
176 /* This is a list of groups of functions for each address
177 * family that we support.
179 struct list_head address_families;
181 /* This is the hash of all endpoints. */
183 struct sctp_hashbucket *ep_hashtable;
185 /* This is the hash of all associations. */
187 struct sctp_hashbucket *assoc_hashtable;
189 /* This is the sctp port control hash. */
192 spinlock_t port_alloc_lock; /* Protects port_rover. */
193 struct sctp_bind_hashbucket *port_hashtable;
195 /* This is the global local address list.
196 * We actively maintain this complete list of interfaces on
197 * the system by catching routing events.
199 * It is a list of sctp_sockaddr_entry.
201 struct list_head local_addr_list;
202 spinlock_t local_addr_lock;
204 /* Flag to indicate if addip is enabled. */
207 /* Flag to indicate if PR-SCTP is enabled. */
211 #define sctp_rto_initial (sctp_globals.rto_initial)
212 #define sctp_rto_min (sctp_globals.rto_min)
213 #define sctp_rto_max (sctp_globals.rto_max)
214 #define sctp_rto_alpha (sctp_globals.rto_alpha)
215 #define sctp_rto_beta (sctp_globals.rto_beta)
216 #define sctp_max_burst (sctp_globals.max_burst)
217 #define sctp_valid_cookie_life (sctp_globals.valid_cookie_life)
218 #define sctp_cookie_preserve_enable (sctp_globals.cookie_preserve_enable)
219 #define sctp_max_retrans_association (sctp_globals.max_retrans_association)
220 #define sctp_sndbuf_policy (sctp_globals.sndbuf_policy)
221 #define sctp_max_retrans_path (sctp_globals.max_retrans_path)
222 #define sctp_max_retrans_init (sctp_globals.max_retrans_init)
223 #define sctp_sack_timeout (sctp_globals.sack_timeout)
224 #define sctp_hb_interval (sctp_globals.hb_interval)
225 #define sctp_max_instreams (sctp_globals.max_instreams)
226 #define sctp_max_outstreams (sctp_globals.max_outstreams)
227 #define sctp_address_families (sctp_globals.address_families)
228 #define sctp_ep_hashsize (sctp_globals.ep_hashsize)
229 #define sctp_ep_hashtable (sctp_globals.ep_hashtable)
230 #define sctp_assoc_hashsize (sctp_globals.assoc_hashsize)
231 #define sctp_assoc_hashtable (sctp_globals.assoc_hashtable)
232 #define sctp_port_hashsize (sctp_globals.port_hashsize)
233 #define sctp_port_rover (sctp_globals.port_rover)
234 #define sctp_port_alloc_lock (sctp_globals.port_alloc_lock)
235 #define sctp_port_hashtable (sctp_globals.port_hashtable)
236 #define sctp_local_addr_list (sctp_globals.local_addr_list)
237 #define sctp_local_addr_lock (sctp_globals.local_addr_lock)
238 #define sctp_addip_enable (sctp_globals.addip_enable)
239 #define sctp_prsctp_enable (sctp_globals.prsctp_enable)
241 /* SCTP Socket type: UDP or TCP style. */
244 SCTP_SOCKET_UDP_HIGH_BANDWIDTH,
246 } sctp_socket_type_t;
248 /* Per socket SCTP information. */
250 /* inet_sock has to be the first member of sctp_sock */
251 struct inet_sock inet;
252 /* What kind of a socket is this? */
253 sctp_socket_type_t type;
255 /* PF_ family specific functions. */
258 /* Access to HMAC transform. */
259 struct crypto_tfm *hmac;
261 /* What is our base endpointer? */
262 struct sctp_endpoint *ep;
264 struct sctp_bind_bucket *bind_hash;
265 /* Various Socket Options. */
266 __u16 default_stream;
269 __u32 default_context;
270 __u32 default_timetolive;
272 struct sctp_initmsg initmsg;
273 struct sctp_rtoinfo rtoinfo;
274 struct sctp_paddrparams paddrparam;
275 struct sctp_event_subscribe subscribe;
276 struct sctp_assocparams assocparams;
280 __u8 disable_fragments;
285 /* Receive to here while partial delivery is in effect. */
286 struct sk_buff_head pd_lobby;
289 static inline struct sctp_sock *sctp_sk(const struct sock *sk)
291 return (struct sctp_sock *)sk;
294 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
296 return (struct sock *)sp;
299 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
301 struct sctp_sock sctp;
302 struct ipv6_pinfo inet6;
304 #endif /* CONFIG_IPV6 */
307 /* This is our APPLICATION-SPECIFIC state cookie.
308 * THIS IS NOT DICTATED BY THE SPECIFICATION.
310 /* These are the parts of an association which we send in the cookie.
311 * Most of these are straight out of:
312 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
318 /* My : Tag expected in every inbound packet and sent
319 * Verification: in the INIT or INIT ACK chunk.
324 /* Peer's : Tag expected in every outbound packet except
325 * Verification: in the INIT chunk.
330 /* The rest of these are not from the spec, but really need to
334 /* My Tie Tag : Assist in discovering a restarting association. */
337 /* Peer's Tie Tag: Assist in discovering a restarting association. */
340 /* When does this cookie expire? */
341 struct timeval expiration;
343 /* Number of inbound/outbound streams which are set
344 * and negotiated during the INIT process.
346 __u16 sinit_num_ostreams;
347 __u16 sinit_max_instreams;
349 /* This is the first sequence number I used. */
352 /* This holds the originating address of the INIT packet. */
353 union sctp_addr peer_addr;
356 * Include the source port of the INIT-ACK
362 /* Padding for future use */
368 /* This is a shim for my peer's INIT packet, followed by
369 * a copy of the raw address list of the association.
370 * The length of the raw address list is saved in the
371 * raw_addr_list_len field, which will be used at the time when
372 * the association TCB is re-constructed from the cookie.
374 __u32 raw_addr_list_len;
375 struct sctp_init_chunk peer_init[0];
379 /* The format of our cookie that we send to our peer. */
380 struct sctp_signed_cookie {
381 __u8 signature[SCTP_SECRET_SIZE];
382 struct sctp_cookie c;
385 /* This is another convenience type to allocate memory for address
386 * params for the maximum size and pass such structures around
389 union sctp_addr_param {
390 struct sctp_ipv4addr_param v4;
391 struct sctp_ipv6addr_param v6;
394 /* A convenience type to allow walking through the various
395 * parameters and avoid casting all over the place.
399 struct sctp_paramhdr *p;
400 struct sctp_cookie_preserve_param *life;
401 struct sctp_hostname_param *dns;
402 struct sctp_cookie_param *cookie;
403 struct sctp_supported_addrs_param *sat;
404 struct sctp_ipv4addr_param *v4;
405 struct sctp_ipv6addr_param *v6;
406 union sctp_addr_param *addr;
407 struct sctp_adaption_ind_param *aind;
410 /* RFC 2960. Section 3.3.5 Heartbeat.
411 * Heartbeat Information: variable length
412 * The Sender-specific Heartbeat Info field should normally include
413 * information about the sender's current time when this HEARTBEAT
414 * chunk is sent and the destination transport address to which this
415 * HEARTBEAT is sent (see Section 8.3).
417 typedef struct sctp_sender_hb_info {
418 struct sctp_paramhdr param_hdr;
419 union sctp_addr daddr;
420 unsigned long sent_at;
421 } __attribute__((packed)) sctp_sender_hb_info_t;
424 * RFC 2960 1.3.2 Sequenced Delivery within Streams
426 * The term "stream" is used in SCTP to refer to a sequence of user
427 * messages that are to be delivered to the upper-layer protocol in
428 * order with respect to other messages within the same stream. This is
429 * in contrast to its usage in TCP, where it refers to a sequence of
430 * bytes (in this document a byte is assumed to be eight bits).
433 * This is the structure we use to track both our outbound and inbound
434 * SSN, or Stream Sequence Numbers.
443 struct sctp_stream in;
444 struct sctp_stream out;
448 struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out, int gfp);
449 void sctp_ssnmap_free(struct sctp_ssnmap *map);
450 void sctp_ssnmap_clear(struct sctp_ssnmap *map);
452 /* What is the current SSN number for this stream? */
453 static inline __u16 sctp_ssn_peek(struct sctp_stream *stream, __u16 id)
455 return stream->ssn[id];
458 /* Return the next SSN number for this stream. */
459 static inline __u16 sctp_ssn_next(struct sctp_stream *stream, __u16 id)
461 return stream->ssn[id]++;
464 /* Skip over this ssn and all below. */
465 static inline void sctp_ssn_skip(struct sctp_stream *stream, __u16 id,
468 stream->ssn[id] = ssn+1;
472 * Pointers to address related SCTP functions.
473 * (i.e. things that depend on the address family.)
476 int (*sctp_xmit) (struct sk_buff *skb,
477 struct sctp_transport *,
479 int (*setsockopt) (struct sock *sk,
484 int (*getsockopt) (struct sock *sk,
489 struct dst_entry *(*get_dst) (struct sctp_association *asoc,
490 union sctp_addr *daddr,
491 union sctp_addr *saddr);
492 void (*get_saddr) (struct sctp_association *asoc,
493 struct dst_entry *dst,
494 union sctp_addr *daddr,
495 union sctp_addr *saddr);
496 void (*copy_addrlist) (struct list_head *,
497 struct net_device *);
498 void (*dst_saddr) (union sctp_addr *saddr,
499 struct dst_entry *dst,
500 unsigned short port);
501 int (*cmp_addr) (const union sctp_addr *addr1,
502 const union sctp_addr *addr2);
503 void (*addr_copy) (union sctp_addr *dst,
504 union sctp_addr *src);
505 void (*from_skb) (union sctp_addr *,
508 void (*from_sk) (union sctp_addr *,
510 void (*to_sk_saddr) (union sctp_addr *,
512 void (*to_sk_daddr) (union sctp_addr *,
514 void (*from_addr_param) (union sctp_addr *,
515 union sctp_addr_param *,
516 __u16 port, int iif);
517 int (*to_addr_param) (const union sctp_addr *,
518 union sctp_addr_param *);
519 int (*addr_valid) (union sctp_addr *,
521 sctp_scope_t (*scope) (union sctp_addr *);
522 void (*inaddr_any) (union sctp_addr *, unsigned short);
523 int (*is_any) (const union sctp_addr *);
524 int (*available) (union sctp_addr *,
526 int (*skb_iif) (const struct sk_buff *sk);
527 int (*is_ce) (const struct sk_buff *sk);
528 void (*seq_dump_addr)(struct seq_file *seq,
529 union sctp_addr *addr);
530 __u16 net_header_len;
532 sa_family_t sa_family;
533 struct list_head list;
536 struct sctp_af *sctp_get_af_specific(sa_family_t);
537 int sctp_register_af(struct sctp_af *);
539 /* Protocol family functions. */
541 void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
542 void (*skb_msgname) (struct sk_buff *, char *, int *);
543 int (*af_supported) (sa_family_t, struct sctp_sock *);
544 int (*cmp_addr) (const union sctp_addr *,
545 const union sctp_addr *,
547 int (*bind_verify) (struct sctp_sock *, union sctp_addr *);
548 int (*send_verify) (struct sctp_sock *, union sctp_addr *);
549 int (*supported_addrs)(const struct sctp_sock *, __u16 *);
550 struct sock *(*create_accept_sk) (struct sock *sk,
551 struct sctp_association *asoc);
552 void (*addr_v4map) (struct sctp_sock *, union sctp_addr *);
557 /* Structure to track chunk fragments that have been acked, but peer
558 * fragments of the same message have not.
560 struct sctp_datamsg {
561 /* Chunks waiting to be submitted to lower layer. */
562 struct list_head chunks;
563 /* Chunks that have been transmitted. */
564 struct list_head track;
565 /* Reference counting. */
567 /* When is this message no longer interesting to the peer? */
568 unsigned long expires_at;
569 /* Did the messenge fail to send? */
572 /* Control whether chunks from this message can be abandoned. */
576 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
577 struct sctp_sndrcvinfo *,
578 struct msghdr *, int len);
579 void sctp_datamsg_put(struct sctp_datamsg *);
580 void sctp_datamsg_free(struct sctp_datamsg *);
581 void sctp_datamsg_track(struct sctp_chunk *);
582 void sctp_chunk_fail(struct sctp_chunk *, int error);
583 int sctp_chunk_abandoned(struct sctp_chunk *);
585 /* RFC2960 1.4 Key Terms
587 * o Chunk: A unit of information within an SCTP packet, consisting of
588 * a chunk header and chunk-specific content.
590 * As a matter of convenience, we remember the SCTP common header for
591 * each chunk as well as a few other header pointers...
594 struct list_head list;
598 /* This is our link to the per-transport transmitted list. */
599 struct list_head transmitted_list;
601 /* This field is used by chunks that hold fragmented data.
602 * For the first fragment this is the list that holds the rest of
603 * fragments. For the remaining fragments, this is the link to the
604 * frag_list maintained in the first fragment.
606 struct list_head frag_list;
608 /* This points to the sk_buff containing the actual data. */
611 /* These are the SCTP headers by reverse order in a packet.
612 * Note that some of these may happen more than once. In that
613 * case, we point at the "current" one, whatever that means
614 * for that level of header.
617 /* We point this at the FIRST TLV parameter to chunk_hdr. */
618 union sctp_params param_hdr;
621 struct sctp_datahdr *data_hdr;
622 struct sctp_inithdr *init_hdr;
623 struct sctp_sackhdr *sack_hdr;
624 struct sctp_heartbeathdr *hb_hdr;
625 struct sctp_sender_hb_info *hbs_hdr;
626 struct sctp_shutdownhdr *shutdown_hdr;
627 struct sctp_signed_cookie *cookie_hdr;
628 struct sctp_ecnehdr *ecne_hdr;
629 struct sctp_cwrhdr *ecn_cwr_hdr;
630 struct sctp_errhdr *err_hdr;
631 struct sctp_addiphdr *addip_hdr;
632 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
637 struct sctp_chunkhdr *chunk_hdr;
638 struct sctphdr *sctp_hdr;
640 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
641 struct sctp_sndrcvinfo sinfo;
643 /* Which association does this belong to? */
644 struct sctp_association *asoc;
646 /* What endpoint received this chunk? */
647 struct sctp_ep_common *rcvr;
649 /* We fill this in if we are calculating RTT. */
650 unsigned long sent_at;
652 /* What is the origin IP address for this chunk? */
653 union sctp_addr source;
654 /* Destination address for this chunk. */
655 union sctp_addr dest;
657 /* For outbound message, track all fragments for SEND_FAILED. */
658 struct sctp_datamsg *msg;
660 /* For an inbound chunk, this tells us where it came from.
661 * For an outbound chunk, it tells us where we'd like it to
662 * go. It is NULL if we have no preference.
664 struct sctp_transport *transport;
666 __u8 rtt_in_progress; /* Is this chunk used for RTT calculation? */
667 __u8 resent; /* Has this chunk ever been retransmitted. */
668 __u8 has_tsn; /* Does this chunk have a TSN yet? */
669 __u8 has_ssn; /* Does this chunk have a SSN yet? */
670 __u8 singleton; /* Was this the only chunk in the packet? */
671 __u8 end_of_packet; /* Was this the last chunk in the packet? */
672 __u8 ecn_ce_done; /* Have we processed the ECN CE bit? */
673 __u8 pdiscard; /* Discard the whole packet now? */
674 __u8 tsn_gap_acked; /* Is this chunk acked by a GAP ACK? */
675 __u8 fast_retransmit; /* Is this chunk fast retransmitted? */
676 __u8 tsn_missing_report; /* Data chunk missing counter. */
679 void sctp_chunk_hold(struct sctp_chunk *);
680 void sctp_chunk_put(struct sctp_chunk *);
681 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
683 void sctp_chunk_free(struct sctp_chunk *);
684 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
685 struct sctp_chunk *sctp_chunkify(struct sk_buff *,
686 const struct sctp_association *,
688 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
690 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
692 /* This is a structure for holding either an IPv6 or an IPv4 address. */
693 /* sin_family -- AF_INET or AF_INET6
694 * sin_port -- ordinary port number
695 * sin_addr -- cast to either (struct in_addr) or (struct in6_addr)
697 struct sctp_sockaddr_entry {
698 struct list_head list;
702 typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *);
704 /* This structure holds lists of chunks as we are assembling for
708 /* These are the SCTP header values (host order) for the packet. */
710 __u16 destination_port;
713 /* This contains the payload chunks. */
714 struct list_head chunk_list;
716 /* This is the overhead of the sctp and ip headers. */
718 /* This is the total size of all chunks INCLUDING padding. */
721 /* The packet is destined for this transport address.
722 * The function we finally use to pass down to the next lower
723 * layer lives in the transport structure.
725 struct sctp_transport *transport;
727 /* This packet contains a COOKIE-ECHO chunk. */
728 char has_cookie_echo;
730 /* This packet containsa SACK chunk. */
733 /* SCTP cannot fragment this packet. So let ip fragment it. */
739 struct sctp_packet *sctp_packet_init(struct sctp_packet *,
740 struct sctp_transport *,
741 __u16 sport, __u16 dport);
742 struct sctp_packet *sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
743 sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *,
744 struct sctp_chunk *);
745 sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *,
746 struct sctp_chunk *);
747 int sctp_packet_transmit(struct sctp_packet *);
748 void sctp_packet_free(struct sctp_packet *);
750 static inline int sctp_packet_empty(struct sctp_packet *packet)
752 return (packet->size == packet->overhead);
755 /* This represents a remote transport address.
756 * For local transport addresses, we just use union sctp_addr.
758 * RFC2960 Section 1.4 Key Terms
760 * o Transport address: A Transport Address is traditionally defined
761 * by Network Layer address, Transport Layer protocol and Transport
762 * Layer port number. In the case of SCTP running over IP, a
763 * transport address is defined by the combination of an IP address
764 * and an SCTP port number (where SCTP is the Transport protocol).
766 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
768 * o The sender keeps a separate congestion control parameter set for
769 * each of the destination addresses it can send to (not each
770 * source-destination pair but for each destination). The parameters
771 * should decay if the address is not used for a long enough time
775 struct sctp_transport {
776 /* A list of transports. */
777 struct list_head transports;
779 /* Reference counting. */
783 /* This is the peer's IP address and port. */
784 union sctp_addr ipaddr;
786 /* These are the functions we call to handle LLP stuff. */
787 struct sctp_af *af_specific;
789 /* Which association do we belong to? */
790 struct sctp_association *asoc;
794 * 12.3 Per Transport Address Data
796 * For each destination transport address in the peer's
797 * address list derived from the INIT or INIT ACK chunk, a
798 * number of data elements needs to be maintained including:
800 __u32 rtt; /* This is the most recent RTT. */
802 /* RTO : The current retransmission timeout value. */
805 /* RTTVAR : The current RTT variation. */
808 /* SRTT : The current smoothed round trip time. */
811 /* RTO-Pending : A flag used to track if one of the DATA
812 * chunks sent to this address is currently being
813 * used to compute a RTT. If this flag is 0,
814 * the next DATA chunk sent to this destination
815 * should be used to compute a RTT and this flag
816 * should be set. Every time the RTT
817 * calculation completes (i.e. the DATA chunk
818 * is SACK'd) clear this flag.
823 * These are the congestion stats.
825 /* cwnd : The current congestion window. */
826 __u32 cwnd; /* This is the actual cwnd. */
828 /* ssthresh : The current slow start threshold value. */
831 /* partial : The tracking method for increase of cwnd when in
832 * bytes acked : congestion avoidance mode (see Section 6.2.2)
834 __u32 partial_bytes_acked;
836 /* Data that has been sent, but not acknowledged. */
839 /* PMTU : The current known path MTU. */
843 struct dst_entry *dst;
844 /* Source address. */
845 union sctp_addr saddr;
847 /* When was the last time(in jiffies) that a data packet was sent on
848 * this transport? This is used to adjust the cwnd when the transport
851 unsigned long last_time_used;
853 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
854 * the destination address every heartbeat interval.
858 /* When was the last time (in jiffies) that we heard from this
859 * transport? We use this to pick new active and retran paths.
861 unsigned long last_time_heard;
863 /* Last time(in jiffies) when cwnd is reduced due to the congestion
864 * indication based on ECNE chunk.
866 unsigned long last_time_ecne_reduced;
868 /* The number of times INIT has been sent on this transport. */
871 /* state : The current state of this destination,
872 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKOWN.
876 /* hb_allowed : The current heartbeat state of this destination,
877 * : i.e. ALLOW-HB, NO-HEARTBEAT, etc.
881 /* These are the error stats for this destination. */
883 /* Error count : The current error count for this destination. */
884 unsigned short error_count;
886 /* This is the max_retrans value for the transport and will
887 * be initialized to proto.max_retrans.path. This can be changed
888 * using SCTP_SET_PEER_ADDR_PARAMS socket option.
892 /* Per : A timer used by each destination.
896 * [Everywhere else in the text this is called T3-rtx. -ed]
898 struct timer_list T3_rtx_timer;
900 /* Heartbeat timer is per destination. */
901 struct timer_list hb_timer;
903 /* Since we're using per-destination retransmission timers
904 * (see above), we're also using per-destination "transmitted"
905 * queues. This probably ought to be a private struct
906 * accessible only within the outqueue, but it's not, yet.
908 struct list_head transmitted;
910 /* We build bundle-able packets for this transport here. */
911 struct sctp_packet packet;
913 /* This is the list of transports that have chunks to send. */
914 struct list_head send_ready;
916 int malloced; /* Is this structure kfree()able? */
918 /* State information saved for SFR_CACC algorithm. The key
919 * idea in SFR_CACC is to maintain state at the sender on a
920 * per-destination basis when a changeover happens.
921 * char changeover_active;
922 * char cycling_changeover;
923 * __u32 next_tsn_at_change;
924 * char cacc_saw_newack;
927 /* An unsigned integer, which stores the next TSN to be
928 * used by the sender, at the moment of changeover.
930 __u32 next_tsn_at_change;
932 /* A flag which indicates the occurrence of a changeover */
933 char changeover_active;
935 /* A flag which indicates whether the change of primary is
936 * the first switch to this destination address during an
939 char cycling_changeover;
941 /* A temporary flag, which is used during the processing of
942 * a SACK to estimate the causative TSN(s)'s group.
944 char cacc_saw_newack;
948 struct sctp_transport *sctp_transport_new(const union sctp_addr *, int);
949 void sctp_transport_set_owner(struct sctp_transport *,
950 struct sctp_association *);
951 void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
953 void sctp_transport_pmtu(struct sctp_transport *);
954 void sctp_transport_free(struct sctp_transport *);
955 void sctp_transport_reset_timers(struct sctp_transport *);
956 void sctp_transport_hold(struct sctp_transport *);
957 void sctp_transport_put(struct sctp_transport *);
958 void sctp_transport_update_rto(struct sctp_transport *, __u32);
959 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
960 void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t);
961 unsigned long sctp_transport_timeout(struct sctp_transport *);
964 /* This is the structure we use to queue packets as they come into
965 * SCTP. We write packets to it and read chunks from it.
968 /* This is actually a queue of sctp_chunk each
969 * containing a partially decoded packet.
971 struct list_head in_chunk_list;
972 /* This is the packet which is currently off the in queue and is
973 * being worked on through the inbound chunk processing.
975 struct sctp_chunk *in_progress;
977 /* This is the delayed task to finish delivering inbound
980 struct work_struct immediate;
982 int malloced; /* Is this structure kfree()able? */
985 void sctp_inq_init(struct sctp_inq *);
986 void sctp_inq_free(struct sctp_inq *);
987 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
988 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
989 void sctp_inq_set_th_handler(struct sctp_inq *, void (*)(void *), void *);
991 /* This is the structure we use to hold outbound chunks. You push
992 * chunks in and they automatically pop out the other end as bundled
993 * packets (it calls (*output_handler)()).
995 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
996 * and 8.2 of the v13 draft.
998 * It handles retransmissions. The connection to the timeout portion
999 * of the state machine is through sctp_..._timeout() and timeout_handler.
1001 * If you feed it SACKs, it will eat them.
1003 * If you give it big chunks, it will fragment them.
1005 * It assigns TSN's to data chunks. This happens at the last possible
1006 * instant before transmission.
1008 * When free()'d, it empties itself out via output_handler().
1011 struct sctp_association *asoc;
1013 /* Data pending that has never been transmitted. */
1014 struct list_head out_chunk_list;
1016 unsigned out_qlen; /* Total length of queued data chunks. */
1018 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1021 /* These are control chunks we want to send. */
1022 struct list_head control_chunk_list;
1024 /* These are chunks that have been sacked but are above the
1025 * CTSN, or cumulative tsn ack point.
1027 struct list_head sacked;
1029 /* Put chunks on this list to schedule them for
1032 struct list_head retransmit;
1034 /* Put chunks on this list to save them for FWD TSN processing as
1035 * they were abandoned.
1037 struct list_head abandoned;
1039 /* How many unackd bytes do we have in-flight? */
1040 __u32 outstanding_bytes;
1045 /* Is this structure empty? */
1048 /* Are we kfree()able? */
1052 void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1053 void sctp_outq_teardown(struct sctp_outq *);
1054 void sctp_outq_free(struct sctp_outq*);
1055 int sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk);
1056 int sctp_outq_flush(struct sctp_outq *, int);
1057 int sctp_outq_sack(struct sctp_outq *, struct sctp_sackhdr *);
1058 int sctp_outq_is_empty(const struct sctp_outq *);
1059 void sctp_outq_restart(struct sctp_outq *);
1061 void sctp_retransmit(struct sctp_outq *, struct sctp_transport *,
1062 sctp_retransmit_reason_t);
1063 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1064 int sctp_outq_uncork(struct sctp_outq *);
1065 /* Uncork and flush an outqueue. */
1066 static inline void sctp_outq_cork(struct sctp_outq *q)
1071 /* These bind address data fields common between endpoints and associations */
1072 struct sctp_bind_addr {
1074 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1076 * SCTP Port: The local SCTP port number the endpoint is
1081 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1083 * Address List: The list of IP addresses that this instance
1084 * has bound. This information is passed to one's
1085 * peer(s) in INIT and INIT ACK chunks.
1087 struct list_head address_list;
1089 int malloced; /* Are we kfree()able? */
1092 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1093 void sctp_bind_addr_free(struct sctp_bind_addr *);
1094 int sctp_bind_addr_copy(struct sctp_bind_addr *dest,
1095 const struct sctp_bind_addr *src,
1096 sctp_scope_t scope, int gfp,int flags);
1097 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1099 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1100 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1101 struct sctp_sock *);
1102 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp,
1103 const union sctp_addr *addrs,
1105 struct sctp_sock *opt);
1106 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1107 int *addrs_len, int gfp);
1108 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1109 __u16 port, int gfp);
1111 sctp_scope_t sctp_scope(const union sctp_addr *);
1112 int sctp_in_scope(const union sctp_addr *addr, const sctp_scope_t scope);
1113 int sctp_is_any(const union sctp_addr *addr);
1114 int sctp_addr_is_valid(const union sctp_addr *addr);
1117 /* What type of endpoint? */
1119 SCTP_EP_TYPE_SOCKET,
1120 SCTP_EP_TYPE_ASSOCIATION,
1121 } sctp_endpoint_type_t;
1124 * A common base class to bridge the implmentation view of a
1125 * socket (usually listening) endpoint versus an association's
1127 * This common structure is useful for several purposes:
1128 * 1) Common interface for lookup routines.
1129 * a) Subfunctions work for either endpoint or association
1130 * b) Single interface to lookup allows hiding the lookup lock rather
1131 * than acquiring it externally.
1132 * 2) Common interface for the inbound chunk handling/state machine.
1133 * 3) Common object handling routines for reference counting, etc.
1134 * 4) Disentangle association lookup from endpoint lookup, where we
1135 * do not have to find our endpoint to find our association.
1139 struct sctp_ep_common {
1140 /* Fields to help us manage our entries in the hash tables. */
1141 struct sctp_ep_common *next;
1142 struct sctp_ep_common **pprev;
1145 /* Runtime type information. What kind of endpoint is this? */
1146 sctp_endpoint_type_t type;
1148 /* Some fields to help us manage this object.
1149 * refcnt - Reference count access to this object.
1150 * dead - Do not attempt to use this object.
1151 * malloced - Do we need to kfree this object?
1157 /* What socket does this endpoint belong to? */
1160 /* This is where we receive inbound chunks. */
1161 struct sctp_inq inqueue;
1163 /* This substructure includes the defining parameters of the
1165 * bind_addr.port is our shared port number.
1166 * bind_addr.address_list is our set of local IP addresses.
1168 struct sctp_bind_addr bind_addr;
1170 /* Protection during address list comparisons. */
1175 /* RFC Section 1.4 Key Terms
1177 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1178 * multi-homed host, an SCTP endpoint is represented to its peers as a
1179 * combination of a set of eligible destination transport addresses to
1180 * which SCTP packets can be sent and a set of eligible source
1181 * transport addresses from which SCTP packets can be received.
1182 * All transport addresses used by an SCTP endpoint must use the
1183 * same port number, but can use multiple IP addresses. A transport
1184 * address used by an SCTP endpoint must not be used by another
1185 * SCTP endpoint. In other words, a transport address is unique
1186 * to an SCTP endpoint.
1188 * From an implementation perspective, each socket has one of these.
1189 * A TCP-style socket will have exactly one association on one of
1190 * these. An UDP-style socket will have multiple associations hanging
1194 struct sctp_endpoint {
1195 /* Common substructure for endpoint and association. */
1196 struct sctp_ep_common base;
1198 /* Associations: A list of current associations and mappings
1199 * to the data consumers for each association. This
1200 * may be in the form of a hash table or other
1201 * implementation dependent structure. The data
1202 * consumers may be process identification
1203 * information such as file descriptors, named pipe
1204 * pointer, or table pointers dependent on how SCTP
1207 /* This is really a list of struct sctp_association entries. */
1208 struct list_head asocs;
1210 /* Secret Key: A secret key used by this endpoint to compute
1211 * the MAC. This SHOULD be a cryptographic quality
1212 * random number with a sufficient length.
1213 * Discussion in [RFC1750] can be helpful in
1214 * selection of the key.
1216 __u8 secret_key[SCTP_HOW_MANY_SECRETS][SCTP_SECRET_SIZE];
1221 /* Default timeouts. */
1222 int timeouts[SCTP_NUM_TIMEOUT_TYPES];
1224 /* sendbuf acct. policy. */
1225 __u32 sndbuf_policy;
1228 /* Recover the outter endpoint structure. */
1229 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1231 struct sctp_endpoint *ep;
1233 ep = container_of(base, struct sctp_endpoint, base);
1237 /* These are function signatures for manipulating endpoints. */
1238 struct sctp_endpoint *sctp_endpoint_new(struct sock *, int);
1239 void sctp_endpoint_free(struct sctp_endpoint *);
1240 void sctp_endpoint_put(struct sctp_endpoint *);
1241 void sctp_endpoint_hold(struct sctp_endpoint *);
1242 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1243 struct sctp_association *sctp_endpoint_lookup_assoc(
1244 const struct sctp_endpoint *ep,
1245 const union sctp_addr *paddr,
1246 struct sctp_transport **);
1247 int sctp_endpoint_is_peeled_off(struct sctp_endpoint *,
1248 const union sctp_addr *);
1249 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1250 const union sctp_addr *);
1251 int sctp_has_association(const union sctp_addr *laddr,
1252 const union sctp_addr *paddr);
1254 int sctp_verify_init(const struct sctp_association *asoc, sctp_cid_t,
1255 sctp_init_chunk_t *peer_init, struct sctp_chunk *chunk,
1256 struct sctp_chunk **err_chunk);
1257 int sctp_process_init(struct sctp_association *, sctp_cid_t cid,
1258 const union sctp_addr *peer,
1259 sctp_init_chunk_t *init, int gfp);
1260 __u32 sctp_generate_tag(const struct sctp_endpoint *);
1261 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
1266 * 12. Recommended Transmission Control Block (TCB) Parameters
1268 * This section details a recommended set of parameters that should
1269 * be contained within the TCB for an implementation. This section is
1270 * for illustrative purposes and should not be deemed as requirements
1271 * on an implementation or as an exhaustive list of all parameters
1272 * inside an SCTP TCB. Each implementation may need its own additional
1273 * parameters for optimization.
1277 /* Here we have information about each individual association. */
1278 struct sctp_association {
1280 /* A base structure common to endpoint and association.
1281 * In this context, it represents the associations's view
1282 * of the local endpoint of the association.
1284 struct sctp_ep_common base;
1286 /* Associations on the same socket. */
1287 struct list_head asocs;
1289 /* association id. */
1290 sctp_assoc_t assoc_id;
1292 /* This is our parent endpoint. */
1293 struct sctp_endpoint *ep;
1295 /* These are those association elements needed in the cookie. */
1296 struct sctp_cookie c;
1298 /* This is all information about our peer. */
1302 * Peer Rwnd : Current calculated value of the peer's rwnd.
1306 /* transport_addr_list
1308 * Peer : A list of SCTP transport addresses that the
1309 * Transport : peer is bound to. This information is derived
1310 * Address : from the INIT or INIT ACK and is used to
1311 * List : associate an inbound packet with a given
1312 * : association. Normally this information is
1313 * : hashed or keyed for quick lookup and access
1315 * : The list is also initialized with the list
1316 * : of addresses passed with the sctp_connectx()
1319 * It is a list of SCTP_transport's.
1321 struct list_head transport_addr_list;
1325 * Peer : A count of the number of peer addresses
1326 * Transport : in the Peer Transport Address List.
1330 __u16 transport_count;
1333 * The transport layer port number.
1339 * Primary : This is the current primary destination
1340 * Path : transport address of the peer endpoint. It
1341 * : may also specify a source transport address
1342 * : on this endpoint.
1344 * All of these paths live on transport_addr_list.
1346 * At the bakeoffs, we discovered that the intent of
1347 * primaryPath is that it only changes when the ULP
1348 * asks to have it changed. We add the activePath to
1349 * designate the connection we are currently using to
1350 * transmit new data and most control chunks.
1352 struct sctp_transport *primary_path;
1354 /* Cache the primary path address here, when we
1355 * need a an address for msg_name.
1357 union sctp_addr primary_addr;
1360 * The path that we are currently using to
1361 * transmit new data and most control chunks.
1363 struct sctp_transport *active_path;
1367 * RFC2960 6.4 Multi-homed SCTP Endpoints
1369 * Furthermore, when its peer is multi-homed, an
1370 * endpoint SHOULD try to retransmit a chunk to an
1371 * active destination transport address that is
1372 * different from the last destination address to
1373 * which the DATA chunk was sent.
1375 struct sctp_transport *retran_path;
1377 /* Pointer to last transport I have sent on. */
1378 struct sctp_transport *last_sent_to;
1380 /* This is the last transport I have received DATA on. */
1381 struct sctp_transport *last_data_from;
1384 * Mapping An array of bits or bytes indicating which out of
1385 * Array order TSN's have been received (relative to the
1386 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1387 * order packets have been received, this array
1388 * will be set to all zero. This structure may be
1389 * in the form of a circular buffer or bit array.
1391 * Last Rcvd : This is the last TSN received in
1392 * TSN : sequence. This value is set initially by
1393 * : taking the peer's Initial TSN, received in
1394 * : the INIT or INIT ACK chunk, and subtracting
1397 * Throughout most of the specification this is called the
1398 * "Cumulative TSN ACK Point". In this case, we
1399 * ignore the advice in 12.2 in favour of the term
1400 * used in the bulk of the text. This value is hidden
1401 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1403 struct sctp_tsnmap tsn_map;
1404 __u8 _map[sctp_tsnmap_storage_size(SCTP_TSN_MAP_SIZE)];
1406 /* Ack State : This flag indicates if the next received
1407 * : packet is to be responded to with a
1408 * : SACK. This is initializedto 0. When a packet
1409 * : is received it is incremented. If this value
1410 * : reaches 2 or more, a SACK is sent and the
1411 * : value is reset to 0. Note: This is used only
1412 * : when no DATA chunks are received out of
1413 * : order. When DATA chunks are out of order,
1414 * : SACK's are not delayed (see Section 6).
1416 __u8 sack_needed; /* Do we need to sack the peer? */
1418 /* These are capabilities which our peer advertised. */
1419 __u8 ecn_capable; /* Can peer do ECN? */
1420 __u8 ipv4_address; /* Peer understands IPv4 addresses? */
1421 __u8 ipv6_address; /* Peer understands IPv6 addresses? */
1422 __u8 hostname_address;/* Peer understands DNS addresses? */
1423 __u8 asconf_capable; /* Does peer support ADDIP? */
1424 __u8 prsctp_capable; /* Can peer do PR-SCTP? */
1426 __u32 adaption_ind; /* Adaption Code point. */
1428 /* This mask is used to disable sending the ASCONF chunk
1429 * with specified parameter to peer.
1431 __u16 addip_disabled_mask;
1433 struct sctp_inithdr i;
1437 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1438 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1439 * Initial TSN Value minus 1
1444 /* State : A state variable indicating what state the
1445 * : association is in, i.e. COOKIE-WAIT,
1446 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1447 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1449 * Note: No "CLOSED" state is illustrated since if a
1450 * association is "CLOSED" its TCB SHOULD be removed.
1452 * In this implementation we DO have a CLOSED
1453 * state which is used during initiation and shutdown.
1455 * State takes values from SCTP_STATE_*.
1459 /* The cookie life I award for any cookie. */
1460 struct timeval cookie_life;
1462 /* Overall : The overall association error count.
1463 * Error Count : [Clear this any time I get something.]
1465 int overall_error_count;
1467 /* These are the association's initial, max, and min RTO values.
1468 * These values will be initialized by system defaults, but can
1469 * be modified via the SCTP_RTOINFO socket option.
1475 /* Maximum number of new data packets that can be sent in a burst. */
1478 /* This is the max_retrans value for the association. This value will
1479 * be initialized initialized from system defaults, but can be
1480 * modified by the SCTP_ASSOCINFO socket option.
1484 /* Maximum number of times the endpoint will retransmit INIT */
1485 __u16 max_init_attempts;
1487 /* How many times have we resent an INIT? */
1490 /* The largest timeout or RTO value to use in attempting an INIT */
1491 __u16 max_init_timeo;
1493 int timeouts[SCTP_NUM_TIMEOUT_TYPES];
1494 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1496 /* Transport to which SHUTDOWN chunk was last sent. */
1497 struct sctp_transport *shutdown_last_sent_to;
1499 /* Transport to which INIT chunk was last sent. */
1500 struct sctp_transport *init_last_sent_to;
1502 /* Next TSN : The next TSN number to be assigned to a new
1503 * : DATA chunk. This is sent in the INIT or INIT
1504 * : ACK chunk to the peer and incremented each
1505 * : time a DATA chunk is assigned a TSN
1506 * : (normally just prior to transmit or during
1512 * Last Rcvd : This is the last TSN received in sequence. This value
1513 * TSN : is set initially by taking the peer's Initial TSN,
1514 * : received in the INIT or INIT ACK chunk, and
1515 * : subtracting one from it.
1517 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1520 __u32 ctsn_ack_point;
1522 /* PR-SCTP Advanced.Peer.Ack.Point */
1523 __u32 adv_peer_ack_point;
1525 /* Highest TSN that is acknowledged by incoming SACKs. */
1526 __u32 highest_sacked;
1528 /* The number of unacknowledged data chunks. Reported through
1529 * the SCTP_STATUS sockopt.
1533 /* This is the association's receive buffer space. This value is used
1534 * to set a_rwnd field in an INIT or a SACK chunk.
1538 /* This is the last advertised value of rwnd over a SACK chunk. */
1541 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1542 * to slop over a maximum of the association's frag_point.
1546 /* This is the sndbuf size in use for the association.
1547 * This corresponds to the sndbuf size for the association,
1548 * as specified in the sk->sndbuf.
1552 /* This is the wait queue head for send requests waiting on
1553 * the association sndbuf space.
1555 wait_queue_head_t wait;
1557 /* Association : The smallest PMTU discovered for all of the
1558 * PMTU : peer's transport addresses.
1562 /* The message size at which SCTP fragmentation will occur. */
1565 /* Counter used to count INIT errors. */
1566 int init_err_counter;
1568 /* Count the number of INIT cycles (for doubling timeout). */
1571 /* Default send parameters. */
1572 __u16 default_stream;
1573 __u16 default_flags;
1575 __u32 default_context;
1576 __u32 default_timetolive;
1578 /* This tracks outbound ssn for a given stream. */
1579 struct sctp_ssnmap *ssnmap;
1581 /* All outbound chunks go through this structure. */
1582 struct sctp_outq outqueue;
1584 /* A smart pipe that will handle reordering and fragmentation,
1585 * as well as handle passing events up to the ULP.
1587 struct sctp_ulpq ulpq;
1589 /* Last TSN that caused an ECNE Chunk to be sent. */
1590 __u32 last_ecne_tsn;
1592 /* Last TSN that caused a CWR Chunk to be sent. */
1595 /* How many duplicated TSNs have we seen? */
1598 /* Number of seconds of idle time before an association is closed. */
1601 /* These are to support
1602 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1603 * and Enforcement of Flow and Message Limits"
1604 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1605 * or "ADDIP" for short.
1610 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1612 * R1) One and only one ASCONF Chunk MAY be in transit and
1613 * unacknowledged at any one time. If a sender, after sending
1614 * an ASCONF chunk, decides it needs to transfer another
1615 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1616 * returns from the previous ASCONF Chunk before sending a
1617 * subsequent ASCONF. Note this restriction binds each side,
1618 * so at any time two ASCONF may be in-transit on any given
1619 * association (one sent from each endpoint).
1621 * [This is our one-and-only-one ASCONF in flight. If we do
1622 * not have an ASCONF in flight, this is NULL.]
1624 struct sctp_chunk *addip_last_asconf;
1626 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1628 * IMPLEMENTATION NOTE: As an optimization a receiver may wish
1629 * to save the last ASCONF-ACK for some predetermined period
1630 * of time and instead of re-processing the ASCONF (with the
1631 * same serial number) it may just re-transmit the
1632 * ASCONF-ACK. It may wish to use the arrival of a new serial
1633 * number to discard the previously saved ASCONF-ACK or any
1634 * other means it may choose to expire the saved ASCONF-ACK.
1636 * [This is our saved ASCONF-ACK. We invalidate it when a new
1637 * ASCONF serial number arrives.]
1639 struct sctp_chunk *addip_last_asconf_ack;
1641 /* These ASCONF chunks are waiting to be sent.
1643 * These chunaks can't be pushed to outqueue until receiving
1644 * ASCONF_ACK for the previous ASCONF indicated by
1645 * addip_last_asconf, so as to guarantee that only one ASCONF
1646 * is in flight at any time.
1648 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1650 * In defining the ASCONF Chunk transfer procedures, it is
1651 * essential that these transfers MUST NOT cause congestion
1652 * within the network. To achieve this, we place these
1653 * restrictions on the transfer of ASCONF Chunks:
1655 * R1) One and only one ASCONF Chunk MAY be in transit and
1656 * unacknowledged at any one time. If a sender, after sending
1657 * an ASCONF chunk, decides it needs to transfer another
1658 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1659 * returns from the previous ASCONF Chunk before sending a
1660 * subsequent ASCONF. Note this restriction binds each side,
1661 * so at any time two ASCONF may be in-transit on any given
1662 * association (one sent from each endpoint).
1665 * [I really think this is EXACTLY the sort of intelligence
1666 * which already resides in sctp_outq. Please move this
1667 * queue and its supporting logic down there. --piggy]
1669 struct list_head addip_chunk_list;
1671 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1673 * A2) A serial number should be assigned to the Chunk. The
1674 * serial number SHOULD be a monotonically increasing
1675 * number. The serial number SHOULD be initialized at
1676 * the start of the association to the same value as the
1677 * Initial TSN and every time a new ASCONF chunk is created
1678 * it is incremented by one after assigning the serial number
1679 * to the newly created chunk.
1682 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
1684 * Serial Number : 32 bits (unsigned integer)
1686 * This value represents a Serial Number for the ASCONF
1687 * Chunk. The valid range of Serial Number is from 0 to
1688 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
1689 * after reaching 4294967295.
1693 /* Need to send an ECNE Chunk? */
1696 /* Is it a temporary association? */
1701 /* An eyecatcher for determining if we are really looking at an
1702 * association data structure.
1705 SCTP_ASSOC_EYECATCHER = 0xa550c123,
1708 /* Recover the outter association structure. */
1709 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
1711 struct sctp_association *asoc;
1713 asoc = container_of(base, struct sctp_association, base);
1717 /* These are function signatures for manipulating associations. */
1720 struct sctp_association *
1721 sctp_association_new(const struct sctp_endpoint *, const struct sock *,
1722 sctp_scope_t scope, int gfp);
1723 void sctp_association_free(struct sctp_association *);
1724 void sctp_association_put(struct sctp_association *);
1725 void sctp_association_hold(struct sctp_association *);
1727 struct sctp_transport *sctp_assoc_choose_init_transport(
1728 struct sctp_association *);
1729 struct sctp_transport *sctp_assoc_choose_shutdown_transport(
1730 struct sctp_association *);
1731 void sctp_assoc_update_retran_path(struct sctp_association *);
1732 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
1733 const union sctp_addr *);
1734 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1735 const union sctp_addr *laddr);
1736 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
1737 const union sctp_addr *address,
1739 const int peer_state);
1740 void sctp_assoc_del_peer(struct sctp_association *asoc,
1741 const union sctp_addr *addr);
1742 void sctp_assoc_rm_peer(struct sctp_association *asoc,
1743 struct sctp_transport *peer);
1744 void sctp_assoc_control_transport(struct sctp_association *,
1745 struct sctp_transport *,
1746 sctp_transport_cmd_t, sctp_sn_error_t);
1747 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
1748 struct sctp_transport *sctp_assoc_is_match(struct sctp_association *,
1749 const union sctp_addr *,
1750 const union sctp_addr *);
1751 void sctp_assoc_migrate(struct sctp_association *, struct sock *);
1752 void sctp_assoc_update(struct sctp_association *old,
1753 struct sctp_association *new);
1755 __u32 sctp_association_get_next_tsn(struct sctp_association *);
1757 void sctp_assoc_sync_pmtu(struct sctp_association *);
1758 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned);
1759 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned);
1760 void sctp_assoc_set_primary(struct sctp_association *,
1761 struct sctp_transport *);
1762 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *, int);
1763 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
1764 struct sctp_cookie*, int gfp);
1766 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1767 const union sctp_addr *ss2);
1768 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
1770 /* A convenience structure to parse out SCTP specific CMSGs. */
1771 typedef struct sctp_cmsgs {
1772 struct sctp_initmsg *init;
1773 struct sctp_sndrcvinfo *info;
1776 /* Structure for tracking memory objects */
1780 } sctp_dbg_objcnt_entry_t;
1782 #endif /* __sctp_structs_h__ */