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 static inline void flip_to_n(union sctp_addr *to, const union sctp_addr *from)
80 if (from->sa.sa_family == AF_INET6)
81 len = sizeof(struct sockaddr_in6);
83 len = sizeof(struct sockaddr);
84 memcpy(to, from, len);
85 to->v4.sin_port = htons(from->v4.sin_port);
88 static inline void flip_to_h(union sctp_addr *to, const union sctp_addr *from)
91 if (from->sa.sa_family == AF_INET6)
92 len = sizeof(struct sockaddr_in6);
94 len = sizeof(struct sockaddr);
95 memcpy(to, from, len);
96 to->v4.sin_port = ntohs(from->v4.sin_port);
99 /* Forward declarations for data structures. */
101 struct sctp_endpoint;
102 struct sctp_association;
103 struct sctp_transport;
108 struct sctp_bind_addr;
110 struct sctp_ep_common;
115 #include <net/sctp/tsnmap.h>
116 #include <net/sctp/ulpevent.h>
117 #include <net/sctp/ulpqueue.h>
119 /* Structures useful for managing bind/connect. */
121 struct sctp_bind_bucket {
123 unsigned short fastreuse;
124 struct sctp_bind_bucket *next;
125 struct sctp_bind_bucket **pprev;
126 struct hlist_head owner;
129 struct sctp_bind_hashbucket {
131 struct sctp_bind_bucket *chain;
134 /* Used for hashing all associations. */
135 struct sctp_hashbucket {
137 struct sctp_ep_common *chain;
138 } __attribute__((__aligned__(8)));
141 /* The SCTP globals structure. */
142 extern struct sctp_globals {
143 /* RFC2960 Section 14. Suggested SCTP Protocol Parameter Values
145 * The following protocol parameters are RECOMMENDED:
147 * RTO.Initial - 3 seconds
149 * RTO.Max - 60 seconds
150 * RTO.Alpha - 1/8 (3 when converted to right shifts.)
151 * RTO.Beta - 1/4 (2 when converted to right shifts.)
153 unsigned int rto_initial;
154 unsigned int rto_min;
155 unsigned int rto_max;
157 /* Note: rto_alpha and rto_beta are really defined as inverse
158 * powers of two to facilitate integer operations.
166 /* Whether Cookie Preservative is enabled(1) or not(0) */
167 int cookie_preserve_enable;
169 /* Valid.Cookie.Life - 60 seconds */
170 unsigned int valid_cookie_life;
172 /* Delayed SACK timeout 200ms default*/
173 unsigned int sack_timeout;
175 /* HB.interval - 30 seconds */
176 unsigned int hb_interval;
178 /* Association.Max.Retrans - 10 attempts
179 * Path.Max.Retrans - 5 attempts (per destination address)
180 * Max.Init.Retransmits - 8 attempts
182 int max_retrans_association;
183 int max_retrans_path;
184 int max_retrans_init;
187 * Policy for preforming sctp/socket accounting
188 * 0 - do socket level accounting, all assocs share sk_sndbuf
189 * 1 - do sctp accounting, each asoc may use sk_sndbuf bytes
194 * Policy for preforming sctp/socket accounting
195 * 0 - do socket level accounting, all assocs share sk_rcvbuf
196 * 1 - do sctp accounting, each asoc may use sk_rcvbuf bytes
200 /* The following variables are implementation specific. */
202 /* Default initialization values to be applied to new associations. */
204 __u16 max_outstreams;
206 /* This is a list of groups of functions for each address
207 * family that we support.
209 struct list_head address_families;
211 /* This is the hash of all endpoints. */
213 struct sctp_hashbucket *ep_hashtable;
215 /* This is the hash of all associations. */
217 struct sctp_hashbucket *assoc_hashtable;
219 /* This is the sctp port control hash. */
222 spinlock_t port_alloc_lock; /* Protects port_rover. */
223 struct sctp_bind_hashbucket *port_hashtable;
225 /* This is the global local address list.
226 * We actively maintain this complete list of interfaces on
227 * the system by catching routing events.
229 * It is a list of sctp_sockaddr_entry.
231 struct list_head local_addr_list;
232 spinlock_t local_addr_lock;
234 /* Flag to indicate if addip is enabled. */
237 /* Flag to indicate if PR-SCTP is enabled. */
241 #define sctp_rto_initial (sctp_globals.rto_initial)
242 #define sctp_rto_min (sctp_globals.rto_min)
243 #define sctp_rto_max (sctp_globals.rto_max)
244 #define sctp_rto_alpha (sctp_globals.rto_alpha)
245 #define sctp_rto_beta (sctp_globals.rto_beta)
246 #define sctp_max_burst (sctp_globals.max_burst)
247 #define sctp_valid_cookie_life (sctp_globals.valid_cookie_life)
248 #define sctp_cookie_preserve_enable (sctp_globals.cookie_preserve_enable)
249 #define sctp_max_retrans_association (sctp_globals.max_retrans_association)
250 #define sctp_sndbuf_policy (sctp_globals.sndbuf_policy)
251 #define sctp_rcvbuf_policy (sctp_globals.rcvbuf_policy)
252 #define sctp_max_retrans_path (sctp_globals.max_retrans_path)
253 #define sctp_max_retrans_init (sctp_globals.max_retrans_init)
254 #define sctp_sack_timeout (sctp_globals.sack_timeout)
255 #define sctp_hb_interval (sctp_globals.hb_interval)
256 #define sctp_max_instreams (sctp_globals.max_instreams)
257 #define sctp_max_outstreams (sctp_globals.max_outstreams)
258 #define sctp_address_families (sctp_globals.address_families)
259 #define sctp_ep_hashsize (sctp_globals.ep_hashsize)
260 #define sctp_ep_hashtable (sctp_globals.ep_hashtable)
261 #define sctp_assoc_hashsize (sctp_globals.assoc_hashsize)
262 #define sctp_assoc_hashtable (sctp_globals.assoc_hashtable)
263 #define sctp_port_hashsize (sctp_globals.port_hashsize)
264 #define sctp_port_rover (sctp_globals.port_rover)
265 #define sctp_port_alloc_lock (sctp_globals.port_alloc_lock)
266 #define sctp_port_hashtable (sctp_globals.port_hashtable)
267 #define sctp_local_addr_list (sctp_globals.local_addr_list)
268 #define sctp_local_addr_lock (sctp_globals.local_addr_lock)
269 #define sctp_addip_enable (sctp_globals.addip_enable)
270 #define sctp_prsctp_enable (sctp_globals.prsctp_enable)
272 /* SCTP Socket type: UDP or TCP style. */
275 SCTP_SOCKET_UDP_HIGH_BANDWIDTH,
277 } sctp_socket_type_t;
279 /* Per socket SCTP information. */
281 /* inet_sock has to be the first member of sctp_sock */
282 struct inet_sock inet;
283 /* What kind of a socket is this? */
284 sctp_socket_type_t type;
286 /* PF_ family specific functions. */
289 /* Access to HMAC transform. */
290 struct crypto_hash *hmac;
292 /* What is our base endpointer? */
293 struct sctp_endpoint *ep;
295 struct sctp_bind_bucket *bind_hash;
296 /* Various Socket Options. */
297 __u16 default_stream;
300 __u32 default_context;
301 __u32 default_timetolive;
303 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
304 * the destination address every heartbeat interval. This value
305 * will be inherited by all new associations.
309 /* This is the max_retrans value for new associations. */
312 /* The initial Path MTU to use for new associations. */
315 /* The default SACK delay timeout for new associations. */
318 /* Flags controling Heartbeat, SACK delay, and Path MTU Discovery. */
321 struct sctp_initmsg initmsg;
322 struct sctp_rtoinfo rtoinfo;
323 struct sctp_paddrparams paddrparam;
324 struct sctp_event_subscribe subscribe;
325 struct sctp_assocparams assocparams;
329 __u8 disable_fragments;
334 /* Receive to here while partial delivery is in effect. */
335 struct sk_buff_head pd_lobby;
338 static inline struct sctp_sock *sctp_sk(const struct sock *sk)
340 return (struct sctp_sock *)sk;
343 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
345 return (struct sock *)sp;
348 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
350 struct sctp_sock sctp;
351 struct ipv6_pinfo inet6;
353 #endif /* CONFIG_IPV6 */
356 /* This is our APPLICATION-SPECIFIC state cookie.
357 * THIS IS NOT DICTATED BY THE SPECIFICATION.
359 /* These are the parts of an association which we send in the cookie.
360 * Most of these are straight out of:
361 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
367 /* My : Tag expected in every inbound packet and sent
368 * Verification: in the INIT or INIT ACK chunk.
373 /* Peer's : Tag expected in every outbound packet except
374 * Verification: in the INIT chunk.
379 /* The rest of these are not from the spec, but really need to
383 /* My Tie Tag : Assist in discovering a restarting association. */
386 /* Peer's Tie Tag: Assist in discovering a restarting association. */
389 /* When does this cookie expire? */
390 struct timeval expiration;
392 /* Number of inbound/outbound streams which are set
393 * and negotiated during the INIT process.
395 __u16 sinit_num_ostreams;
396 __u16 sinit_max_instreams;
398 /* This is the first sequence number I used. */
401 /* This holds the originating address of the INIT packet. */
402 union sctp_addr peer_addr;
405 * Include the source port of the INIT-ACK
411 /* Padding for future use */
417 /* This is a shim for my peer's INIT packet, followed by
418 * a copy of the raw address list of the association.
419 * The length of the raw address list is saved in the
420 * raw_addr_list_len field, which will be used at the time when
421 * the association TCB is re-constructed from the cookie.
423 __u32 raw_addr_list_len;
424 struct sctp_init_chunk peer_init[0];
428 /* The format of our cookie that we send to our peer. */
429 struct sctp_signed_cookie {
430 __u8 signature[SCTP_SECRET_SIZE];
431 __u32 __pad; /* force sctp_cookie alignment to 64 bits */
432 struct sctp_cookie c;
433 } __attribute__((packed));
435 /* This is another convenience type to allocate memory for address
436 * params for the maximum size and pass such structures around
439 union sctp_addr_param {
440 struct sctp_ipv4addr_param v4;
441 struct sctp_ipv6addr_param v6;
444 /* A convenience type to allow walking through the various
445 * parameters and avoid casting all over the place.
449 struct sctp_paramhdr *p;
450 struct sctp_cookie_preserve_param *life;
451 struct sctp_hostname_param *dns;
452 struct sctp_cookie_param *cookie;
453 struct sctp_supported_addrs_param *sat;
454 struct sctp_ipv4addr_param *v4;
455 struct sctp_ipv6addr_param *v6;
456 union sctp_addr_param *addr;
457 struct sctp_adaption_ind_param *aind;
460 /* RFC 2960. Section 3.3.5 Heartbeat.
461 * Heartbeat Information: variable length
462 * The Sender-specific Heartbeat Info field should normally include
463 * information about the sender's current time when this HEARTBEAT
464 * chunk is sent and the destination transport address to which this
465 * HEARTBEAT is sent (see Section 8.3).
467 typedef struct sctp_sender_hb_info {
468 struct sctp_paramhdr param_hdr;
469 union sctp_addr daddr;
470 unsigned long sent_at;
472 } __attribute__((packed)) sctp_sender_hb_info_t;
475 * RFC 2960 1.3.2 Sequenced Delivery within Streams
477 * The term "stream" is used in SCTP to refer to a sequence of user
478 * messages that are to be delivered to the upper-layer protocol in
479 * order with respect to other messages within the same stream. This is
480 * in contrast to its usage in TCP, where it refers to a sequence of
481 * bytes (in this document a byte is assumed to be eight bits).
484 * This is the structure we use to track both our outbound and inbound
485 * SSN, or Stream Sequence Numbers.
494 struct sctp_stream in;
495 struct sctp_stream out;
499 struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out,
501 void sctp_ssnmap_free(struct sctp_ssnmap *map);
502 void sctp_ssnmap_clear(struct sctp_ssnmap *map);
504 /* What is the current SSN number for this stream? */
505 static inline __u16 sctp_ssn_peek(struct sctp_stream *stream, __u16 id)
507 return stream->ssn[id];
510 /* Return the next SSN number for this stream. */
511 static inline __u16 sctp_ssn_next(struct sctp_stream *stream, __u16 id)
513 return stream->ssn[id]++;
516 /* Skip over this ssn and all below. */
517 static inline void sctp_ssn_skip(struct sctp_stream *stream, __u16 id,
520 stream->ssn[id] = ssn+1;
524 * Pointers to address related SCTP functions.
525 * (i.e. things that depend on the address family.)
528 int (*sctp_xmit) (struct sk_buff *skb,
529 struct sctp_transport *,
531 int (*setsockopt) (struct sock *sk,
536 int (*getsockopt) (struct sock *sk,
541 int (*compat_setsockopt) (struct sock *sk,
546 int (*compat_getsockopt) (struct sock *sk,
551 struct dst_entry *(*get_dst) (struct sctp_association *asoc,
552 union sctp_addr *daddr,
553 union sctp_addr *saddr);
554 void (*get_saddr) (struct sctp_association *asoc,
555 struct dst_entry *dst,
556 union sctp_addr *daddr,
557 union sctp_addr *saddr);
558 void (*copy_addrlist) (struct list_head *,
559 struct net_device *);
560 void (*dst_saddr) (union sctp_addr *saddr,
561 struct dst_entry *dst,
563 int (*cmp_addr) (const union sctp_addr *addr1,
564 const union sctp_addr *addr2);
565 void (*addr_copy) (union sctp_addr *dst,
566 union sctp_addr *src);
567 void (*from_skb) (union sctp_addr *,
570 void (*from_sk) (union sctp_addr *,
572 void (*to_sk_saddr) (union sctp_addr *,
574 void (*to_sk_daddr) (union sctp_addr *,
576 void (*from_addr_param) (union sctp_addr *,
577 union sctp_addr_param *,
578 __u16 port, int iif);
579 int (*to_addr_param) (const union sctp_addr *,
580 union sctp_addr_param *);
581 int (*addr_valid) (union sctp_addr *,
583 const struct sk_buff *);
584 sctp_scope_t (*scope) (union sctp_addr *);
585 void (*inaddr_any) (union sctp_addr *, unsigned short);
586 int (*is_any) (const union sctp_addr *);
587 int (*available) (union sctp_addr *,
589 int (*skb_iif) (const struct sk_buff *sk);
590 int (*is_ce) (const struct sk_buff *sk);
591 void (*seq_dump_addr)(struct seq_file *seq,
592 union sctp_addr *addr);
593 __u16 net_header_len;
595 sa_family_t sa_family;
596 struct list_head list;
599 struct sctp_af *sctp_get_af_specific(sa_family_t);
600 int sctp_register_af(struct sctp_af *);
602 /* Protocol family functions. */
604 void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
605 void (*skb_msgname) (struct sk_buff *, char *, int *);
606 int (*af_supported) (sa_family_t, struct sctp_sock *);
607 int (*cmp_addr) (const union sctp_addr *,
608 const union sctp_addr *,
610 int (*bind_verify) (struct sctp_sock *, union sctp_addr *);
611 int (*send_verify) (struct sctp_sock *, union sctp_addr *);
612 int (*supported_addrs)(const struct sctp_sock *, __u16 *);
613 struct sock *(*create_accept_sk) (struct sock *sk,
614 struct sctp_association *asoc);
615 void (*addr_v4map) (struct sctp_sock *, union sctp_addr *);
620 /* Structure to track chunk fragments that have been acked, but peer
621 * fragments of the same message have not.
623 struct sctp_datamsg {
624 /* Chunks waiting to be submitted to lower layer. */
625 struct list_head chunks;
626 /* Chunks that have been transmitted. */
627 struct list_head track;
628 /* Reference counting. */
630 /* When is this message no longer interesting to the peer? */
631 unsigned long expires_at;
632 /* Did the messenge fail to send? */
635 /* Control whether chunks from this message can be abandoned. */
639 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
640 struct sctp_sndrcvinfo *,
641 struct msghdr *, int len);
642 void sctp_datamsg_put(struct sctp_datamsg *);
643 void sctp_datamsg_free(struct sctp_datamsg *);
644 void sctp_datamsg_track(struct sctp_chunk *);
645 void sctp_chunk_fail(struct sctp_chunk *, int error);
646 int sctp_chunk_abandoned(struct sctp_chunk *);
648 /* RFC2960 1.4 Key Terms
650 * o Chunk: A unit of information within an SCTP packet, consisting of
651 * a chunk header and chunk-specific content.
653 * As a matter of convenience, we remember the SCTP common header for
654 * each chunk as well as a few other header pointers...
657 struct list_head list;
661 /* This is our link to the per-transport transmitted list. */
662 struct list_head transmitted_list;
664 /* This field is used by chunks that hold fragmented data.
665 * For the first fragment this is the list that holds the rest of
666 * fragments. For the remaining fragments, this is the link to the
667 * frag_list maintained in the first fragment.
669 struct list_head frag_list;
671 /* This points to the sk_buff containing the actual data. */
674 /* These are the SCTP headers by reverse order in a packet.
675 * Note that some of these may happen more than once. In that
676 * case, we point at the "current" one, whatever that means
677 * for that level of header.
680 /* We point this at the FIRST TLV parameter to chunk_hdr. */
681 union sctp_params param_hdr;
684 struct sctp_datahdr *data_hdr;
685 struct sctp_inithdr *init_hdr;
686 struct sctp_sackhdr *sack_hdr;
687 struct sctp_heartbeathdr *hb_hdr;
688 struct sctp_sender_hb_info *hbs_hdr;
689 struct sctp_shutdownhdr *shutdown_hdr;
690 struct sctp_signed_cookie *cookie_hdr;
691 struct sctp_ecnehdr *ecne_hdr;
692 struct sctp_cwrhdr *ecn_cwr_hdr;
693 struct sctp_errhdr *err_hdr;
694 struct sctp_addiphdr *addip_hdr;
695 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
700 struct sctp_chunkhdr *chunk_hdr;
701 struct sctphdr *sctp_hdr;
703 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
704 struct sctp_sndrcvinfo sinfo;
706 /* Which association does this belong to? */
707 struct sctp_association *asoc;
709 /* What endpoint received this chunk? */
710 struct sctp_ep_common *rcvr;
712 /* We fill this in if we are calculating RTT. */
713 unsigned long sent_at;
715 /* What is the origin IP address for this chunk? */
716 union sctp_addr source;
717 union sctp_addr source_h;
718 /* Destination address for this chunk. */
719 union sctp_addr dest;
721 /* For outbound message, track all fragments for SEND_FAILED. */
722 struct sctp_datamsg *msg;
724 /* For an inbound chunk, this tells us where it came from.
725 * For an outbound chunk, it tells us where we'd like it to
726 * go. It is NULL if we have no preference.
728 struct sctp_transport *transport;
730 __u8 rtt_in_progress; /* Is this chunk used for RTT calculation? */
731 __u8 resent; /* Has this chunk ever been retransmitted. */
732 __u8 has_tsn; /* Does this chunk have a TSN yet? */
733 __u8 has_ssn; /* Does this chunk have a SSN yet? */
734 __u8 singleton; /* Was this the only chunk in the packet? */
735 __u8 end_of_packet; /* Was this the last chunk in the packet? */
736 __u8 ecn_ce_done; /* Have we processed the ECN CE bit? */
737 __u8 pdiscard; /* Discard the whole packet now? */
738 __u8 tsn_gap_acked; /* Is this chunk acked by a GAP ACK? */
739 __s8 fast_retransmit; /* Is this chunk fast retransmitted? */
740 __u8 tsn_missing_report; /* Data chunk missing counter. */
741 __u8 data_accepted; /* At least 1 chunk in this packet accepted */
744 void sctp_chunk_hold(struct sctp_chunk *);
745 void sctp_chunk_put(struct sctp_chunk *);
746 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
748 void sctp_chunk_free(struct sctp_chunk *);
749 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
750 struct sctp_chunk *sctp_chunkify(struct sk_buff *,
751 const struct sctp_association *,
753 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
755 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
757 /* This is a structure for holding either an IPv6 or an IPv4 address. */
758 struct sctp_sockaddr_entry {
759 struct list_head list;
765 typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *);
767 /* This structure holds lists of chunks as we are assembling for
771 /* These are the SCTP header values (host order) for the packet. */
773 __u16 destination_port;
776 /* This contains the payload chunks. */
777 struct list_head chunk_list;
779 /* This is the overhead of the sctp and ip headers. */
781 /* This is the total size of all chunks INCLUDING padding. */
784 /* The packet is destined for this transport address.
785 * The function we finally use to pass down to the next lower
786 * layer lives in the transport structure.
788 struct sctp_transport *transport;
790 /* This packet contains a COOKIE-ECHO chunk. */
791 char has_cookie_echo;
793 /* This packet containsa SACK chunk. */
796 /* SCTP cannot fragment this packet. So let ip fragment it. */
802 struct sctp_packet *sctp_packet_init(struct sctp_packet *,
803 struct sctp_transport *,
804 __u16 sport, __u16 dport);
805 struct sctp_packet *sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
806 sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *,
807 struct sctp_chunk *);
808 sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *,
809 struct sctp_chunk *);
810 int sctp_packet_transmit(struct sctp_packet *);
811 void sctp_packet_free(struct sctp_packet *);
813 static inline int sctp_packet_empty(struct sctp_packet *packet)
815 return (packet->size == packet->overhead);
818 /* This represents a remote transport address.
819 * For local transport addresses, we just use union sctp_addr.
821 * RFC2960 Section 1.4 Key Terms
823 * o Transport address: A Transport Address is traditionally defined
824 * by Network Layer address, Transport Layer protocol and Transport
825 * Layer port number. In the case of SCTP running over IP, a
826 * transport address is defined by the combination of an IP address
827 * and an SCTP port number (where SCTP is the Transport protocol).
829 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
831 * o The sender keeps a separate congestion control parameter set for
832 * each of the destination addresses it can send to (not each
833 * source-destination pair but for each destination). The parameters
834 * should decay if the address is not used for a long enough time
838 struct sctp_transport {
839 /* A list of transports. */
840 struct list_head transports;
842 /* Reference counting. */
846 /* This is the peer's IP address and port. */
847 union sctp_addr ipaddr;
848 union sctp_addr ipaddr_h;
850 /* These are the functions we call to handle LLP stuff. */
851 struct sctp_af *af_specific;
853 /* Which association do we belong to? */
854 struct sctp_association *asoc;
858 * 12.3 Per Transport Address Data
860 * For each destination transport address in the peer's
861 * address list derived from the INIT or INIT ACK chunk, a
862 * number of data elements needs to be maintained including:
864 __u32 rtt; /* This is the most recent RTT. */
866 /* RTO : The current retransmission timeout value. */
869 /* RTTVAR : The current RTT variation. */
872 /* SRTT : The current smoothed round trip time. */
875 /* RTO-Pending : A flag used to track if one of the DATA
876 * chunks sent to this address is currently being
877 * used to compute a RTT. If this flag is 0,
878 * the next DATA chunk sent to this destination
879 * should be used to compute a RTT and this flag
880 * should be set. Every time the RTT
881 * calculation completes (i.e. the DATA chunk
882 * is SACK'd) clear this flag.
887 * These are the congestion stats.
889 /* cwnd : The current congestion window. */
890 __u32 cwnd; /* This is the actual cwnd. */
892 /* ssthresh : The current slow start threshold value. */
895 /* partial : The tracking method for increase of cwnd when in
896 * bytes acked : congestion avoidance mode (see Section 6.2.2)
898 __u32 partial_bytes_acked;
900 /* Data that has been sent, but not acknowledged. */
904 struct dst_entry *dst;
905 /* Source address. */
906 union sctp_addr saddr;
907 union sctp_addr saddr_h;
909 /* When was the last time(in jiffies) that a data packet was sent on
910 * this transport? This is used to adjust the cwnd when the transport
913 unsigned long last_time_used;
915 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
916 * the destination address every heartbeat interval.
918 unsigned long hbinterval;
920 /* SACK delay timeout */
921 unsigned long sackdelay;
923 /* When was the last time (in jiffies) that we heard from this
924 * transport? We use this to pick new active and retran paths.
926 unsigned long last_time_heard;
928 /* Last time(in jiffies) when cwnd is reduced due to the congestion
929 * indication based on ECNE chunk.
931 unsigned long last_time_ecne_reduced;
933 /* This is the max_retrans value for the transport and will
934 * be initialized from the assocs value. This can be changed
935 * using SCTP_SET_PEER_ADDR_PARAMS socket option.
939 /* PMTU : The current known path MTU. */
942 /* Flags controling Heartbeat, SACK delay, and Path MTU Discovery. */
945 /* The number of times INIT has been sent on this transport. */
948 /* state : The current state of this destination,
949 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKOWN.
953 /* These are the error stats for this destination. */
955 /* Error count : The current error count for this destination. */
956 unsigned short error_count;
958 /* Per : A timer used by each destination.
962 * [Everywhere else in the text this is called T3-rtx. -ed]
964 struct timer_list T3_rtx_timer;
966 /* Heartbeat timer is per destination. */
967 struct timer_list hb_timer;
969 /* Since we're using per-destination retransmission timers
970 * (see above), we're also using per-destination "transmitted"
971 * queues. This probably ought to be a private struct
972 * accessible only within the outqueue, but it's not, yet.
974 struct list_head transmitted;
976 /* We build bundle-able packets for this transport here. */
977 struct sctp_packet packet;
979 /* This is the list of transports that have chunks to send. */
980 struct list_head send_ready;
982 int malloced; /* Is this structure kfree()able? */
984 /* State information saved for SFR_CACC algorithm. The key
985 * idea in SFR_CACC is to maintain state at the sender on a
986 * per-destination basis when a changeover happens.
987 * char changeover_active;
988 * char cycling_changeover;
989 * __u32 next_tsn_at_change;
990 * char cacc_saw_newack;
993 /* An unsigned integer, which stores the next TSN to be
994 * used by the sender, at the moment of changeover.
996 __u32 next_tsn_at_change;
998 /* A flag which indicates the occurrence of a changeover */
999 char changeover_active;
1001 /* A flag which indicates whether the change of primary is
1002 * the first switch to this destination address during an
1005 char cycling_changeover;
1007 /* A temporary flag, which is used during the processing of
1008 * a SACK to estimate the causative TSN(s)'s group.
1010 char cacc_saw_newack;
1013 /* 64-bit random number sent with heartbeat. */
1017 struct sctp_transport *sctp_transport_new(const union sctp_addr *,
1019 void sctp_transport_set_owner(struct sctp_transport *,
1020 struct sctp_association *);
1021 void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
1022 struct sctp_sock *);
1023 void sctp_transport_pmtu(struct sctp_transport *);
1024 void sctp_transport_free(struct sctp_transport *);
1025 void sctp_transport_reset_timers(struct sctp_transport *);
1026 void sctp_transport_hold(struct sctp_transport *);
1027 void sctp_transport_put(struct sctp_transport *);
1028 void sctp_transport_update_rto(struct sctp_transport *, __u32);
1029 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
1030 void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t);
1031 unsigned long sctp_transport_timeout(struct sctp_transport *);
1034 /* This is the structure we use to queue packets as they come into
1035 * SCTP. We write packets to it and read chunks from it.
1038 /* This is actually a queue of sctp_chunk each
1039 * containing a partially decoded packet.
1041 struct list_head in_chunk_list;
1042 /* This is the packet which is currently off the in queue and is
1043 * being worked on through the inbound chunk processing.
1045 struct sctp_chunk *in_progress;
1047 /* This is the delayed task to finish delivering inbound
1050 struct work_struct immediate;
1052 int malloced; /* Is this structure kfree()able? */
1055 void sctp_inq_init(struct sctp_inq *);
1056 void sctp_inq_free(struct sctp_inq *);
1057 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
1058 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
1059 void sctp_inq_set_th_handler(struct sctp_inq *, void (*)(void *), void *);
1061 /* This is the structure we use to hold outbound chunks. You push
1062 * chunks in and they automatically pop out the other end as bundled
1063 * packets (it calls (*output_handler)()).
1065 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1066 * and 8.2 of the v13 draft.
1068 * It handles retransmissions. The connection to the timeout portion
1069 * of the state machine is through sctp_..._timeout() and timeout_handler.
1071 * If you feed it SACKs, it will eat them.
1073 * If you give it big chunks, it will fragment them.
1075 * It assigns TSN's to data chunks. This happens at the last possible
1076 * instant before transmission.
1078 * When free()'d, it empties itself out via output_handler().
1081 struct sctp_association *asoc;
1083 /* Data pending that has never been transmitted. */
1084 struct list_head out_chunk_list;
1086 unsigned out_qlen; /* Total length of queued data chunks. */
1088 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1091 /* These are control chunks we want to send. */
1092 struct list_head control_chunk_list;
1094 /* These are chunks that have been sacked but are above the
1095 * CTSN, or cumulative tsn ack point.
1097 struct list_head sacked;
1099 /* Put chunks on this list to schedule them for
1102 struct list_head retransmit;
1104 /* Put chunks on this list to save them for FWD TSN processing as
1105 * they were abandoned.
1107 struct list_head abandoned;
1109 /* How many unackd bytes do we have in-flight? */
1110 __u32 outstanding_bytes;
1115 /* Is this structure empty? */
1118 /* Are we kfree()able? */
1122 void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1123 void sctp_outq_teardown(struct sctp_outq *);
1124 void sctp_outq_free(struct sctp_outq*);
1125 int sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk);
1126 int sctp_outq_flush(struct sctp_outq *, int);
1127 int sctp_outq_sack(struct sctp_outq *, struct sctp_sackhdr *);
1128 int sctp_outq_is_empty(const struct sctp_outq *);
1129 void sctp_outq_restart(struct sctp_outq *);
1131 void sctp_retransmit(struct sctp_outq *, struct sctp_transport *,
1132 sctp_retransmit_reason_t);
1133 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1134 int sctp_outq_uncork(struct sctp_outq *);
1135 /* Uncork and flush an outqueue. */
1136 static inline void sctp_outq_cork(struct sctp_outq *q)
1141 /* These bind address data fields common between endpoints and associations */
1142 struct sctp_bind_addr {
1144 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1146 * SCTP Port: The local SCTP port number the endpoint is
1151 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1153 * Address List: The list of IP addresses that this instance
1154 * has bound. This information is passed to one's
1155 * peer(s) in INIT and INIT ACK chunks.
1157 struct list_head address_list;
1159 int malloced; /* Are we kfree()able? */
1162 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1163 void sctp_bind_addr_free(struct sctp_bind_addr *);
1164 int sctp_bind_addr_copy(struct sctp_bind_addr *dest,
1165 const struct sctp_bind_addr *src,
1166 sctp_scope_t scope, gfp_t gfp,
1168 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1169 __u8 use_as_src, gfp_t gfp);
1170 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1171 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1172 struct sctp_sock *);
1173 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp,
1174 const union sctp_addr *addrs,
1176 struct sctp_sock *opt);
1177 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1180 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1181 __u16 port, gfp_t gfp);
1183 sctp_scope_t sctp_scope(const union sctp_addr *);
1184 int sctp_in_scope(const union sctp_addr *addr, const sctp_scope_t scope);
1185 int sctp_is_any(const union sctp_addr *addr);
1186 int sctp_addr_is_valid(const union sctp_addr *addr);
1189 /* What type of endpoint? */
1191 SCTP_EP_TYPE_SOCKET,
1192 SCTP_EP_TYPE_ASSOCIATION,
1193 } sctp_endpoint_type_t;
1196 * A common base class to bridge the implmentation view of a
1197 * socket (usually listening) endpoint versus an association's
1199 * This common structure is useful for several purposes:
1200 * 1) Common interface for lookup routines.
1201 * a) Subfunctions work for either endpoint or association
1202 * b) Single interface to lookup allows hiding the lookup lock rather
1203 * than acquiring it externally.
1204 * 2) Common interface for the inbound chunk handling/state machine.
1205 * 3) Common object handling routines for reference counting, etc.
1206 * 4) Disentangle association lookup from endpoint lookup, where we
1207 * do not have to find our endpoint to find our association.
1211 struct sctp_ep_common {
1212 /* Fields to help us manage our entries in the hash tables. */
1213 struct sctp_ep_common *next;
1214 struct sctp_ep_common **pprev;
1217 /* Runtime type information. What kind of endpoint is this? */
1218 sctp_endpoint_type_t type;
1220 /* Some fields to help us manage this object.
1221 * refcnt - Reference count access to this object.
1222 * dead - Do not attempt to use this object.
1223 * malloced - Do we need to kfree this object?
1229 /* What socket does this endpoint belong to? */
1232 /* This is where we receive inbound chunks. */
1233 struct sctp_inq inqueue;
1235 /* This substructure includes the defining parameters of the
1237 * bind_addr.port is our shared port number.
1238 * bind_addr.address_list is our set of local IP addresses.
1240 struct sctp_bind_addr bind_addr;
1242 /* Protection during address list comparisons. */
1247 /* RFC Section 1.4 Key Terms
1249 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1250 * multi-homed host, an SCTP endpoint is represented to its peers as a
1251 * combination of a set of eligible destination transport addresses to
1252 * which SCTP packets can be sent and a set of eligible source
1253 * transport addresses from which SCTP packets can be received.
1254 * All transport addresses used by an SCTP endpoint must use the
1255 * same port number, but can use multiple IP addresses. A transport
1256 * address used by an SCTP endpoint must not be used by another
1257 * SCTP endpoint. In other words, a transport address is unique
1258 * to an SCTP endpoint.
1260 * From an implementation perspective, each socket has one of these.
1261 * A TCP-style socket will have exactly one association on one of
1262 * these. An UDP-style socket will have multiple associations hanging
1266 struct sctp_endpoint {
1267 /* Common substructure for endpoint and association. */
1268 struct sctp_ep_common base;
1270 /* Associations: A list of current associations and mappings
1271 * to the data consumers for each association. This
1272 * may be in the form of a hash table or other
1273 * implementation dependent structure. The data
1274 * consumers may be process identification
1275 * information such as file descriptors, named pipe
1276 * pointer, or table pointers dependent on how SCTP
1279 /* This is really a list of struct sctp_association entries. */
1280 struct list_head asocs;
1282 /* Secret Key: A secret key used by this endpoint to compute
1283 * the MAC. This SHOULD be a cryptographic quality
1284 * random number with a sufficient length.
1285 * Discussion in [RFC1750] can be helpful in
1286 * selection of the key.
1288 __u8 secret_key[SCTP_HOW_MANY_SECRETS][SCTP_SECRET_SIZE];
1293 /* digest: This is a digest of the sctp cookie. This field is
1294 * only used on the receive path when we try to validate
1295 * that the cookie has not been tampered with. We put
1296 * this here so we pre-allocate this once and can re-use
1301 /* sendbuf acct. policy. */
1302 __u32 sndbuf_policy;
1304 /* rcvbuf acct. policy. */
1305 __u32 rcvbuf_policy;
1308 /* Recover the outter endpoint structure. */
1309 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1311 struct sctp_endpoint *ep;
1313 ep = container_of(base, struct sctp_endpoint, base);
1317 /* These are function signatures for manipulating endpoints. */
1318 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1319 void sctp_endpoint_free(struct sctp_endpoint *);
1320 void sctp_endpoint_put(struct sctp_endpoint *);
1321 void sctp_endpoint_hold(struct sctp_endpoint *);
1322 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1323 struct sctp_association *sctp_endpoint_lookup_assoc(
1324 const struct sctp_endpoint *ep,
1325 const union sctp_addr *paddr,
1326 struct sctp_transport **);
1327 int sctp_endpoint_is_peeled_off(struct sctp_endpoint *,
1328 const union sctp_addr *);
1329 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1330 const union sctp_addr *);
1331 int sctp_has_association(const union sctp_addr *laddr,
1332 const union sctp_addr *paddr);
1334 int sctp_verify_init(const struct sctp_association *asoc, sctp_cid_t,
1335 sctp_init_chunk_t *peer_init, struct sctp_chunk *chunk,
1336 struct sctp_chunk **err_chunk);
1337 int sctp_process_init(struct sctp_association *, sctp_cid_t cid,
1338 const union sctp_addr *peer,
1339 sctp_init_chunk_t *init, gfp_t gfp);
1340 __u32 sctp_generate_tag(const struct sctp_endpoint *);
1341 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
1346 * 12. Recommended Transmission Control Block (TCB) Parameters
1348 * This section details a recommended set of parameters that should
1349 * be contained within the TCB for an implementation. This section is
1350 * for illustrative purposes and should not be deemed as requirements
1351 * on an implementation or as an exhaustive list of all parameters
1352 * inside an SCTP TCB. Each implementation may need its own additional
1353 * parameters for optimization.
1357 /* Here we have information about each individual association. */
1358 struct sctp_association {
1360 /* A base structure common to endpoint and association.
1361 * In this context, it represents the associations's view
1362 * of the local endpoint of the association.
1364 struct sctp_ep_common base;
1366 /* Associations on the same socket. */
1367 struct list_head asocs;
1369 /* association id. */
1370 sctp_assoc_t assoc_id;
1372 /* This is our parent endpoint. */
1373 struct sctp_endpoint *ep;
1375 /* These are those association elements needed in the cookie. */
1376 struct sctp_cookie c;
1378 /* This is all information about our peer. */
1382 * Peer Rwnd : Current calculated value of the peer's rwnd.
1386 /* transport_addr_list
1388 * Peer : A list of SCTP transport addresses that the
1389 * Transport : peer is bound to. This information is derived
1390 * Address : from the INIT or INIT ACK and is used to
1391 * List : associate an inbound packet with a given
1392 * : association. Normally this information is
1393 * : hashed or keyed for quick lookup and access
1395 * : The list is also initialized with the list
1396 * : of addresses passed with the sctp_connectx()
1399 * It is a list of SCTP_transport's.
1401 struct list_head transport_addr_list;
1405 * Peer : A count of the number of peer addresses
1406 * Transport : in the Peer Transport Address List.
1410 __u16 transport_count;
1413 * The transport layer port number.
1419 * Primary : This is the current primary destination
1420 * Path : transport address of the peer endpoint. It
1421 * : may also specify a source transport address
1422 * : on this endpoint.
1424 * All of these paths live on transport_addr_list.
1426 * At the bakeoffs, we discovered that the intent of
1427 * primaryPath is that it only changes when the ULP
1428 * asks to have it changed. We add the activePath to
1429 * designate the connection we are currently using to
1430 * transmit new data and most control chunks.
1432 struct sctp_transport *primary_path;
1434 /* Cache the primary path address here, when we
1435 * need a an address for msg_name.
1437 union sctp_addr primary_addr;
1440 * The path that we are currently using to
1441 * transmit new data and most control chunks.
1443 struct sctp_transport *active_path;
1447 * RFC2960 6.4 Multi-homed SCTP Endpoints
1449 * Furthermore, when its peer is multi-homed, an
1450 * endpoint SHOULD try to retransmit a chunk to an
1451 * active destination transport address that is
1452 * different from the last destination address to
1453 * which the DATA chunk was sent.
1455 struct sctp_transport *retran_path;
1457 /* Pointer to last transport I have sent on. */
1458 struct sctp_transport *last_sent_to;
1460 /* This is the last transport I have received DATA on. */
1461 struct sctp_transport *last_data_from;
1464 * Mapping An array of bits or bytes indicating which out of
1465 * Array order TSN's have been received (relative to the
1466 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1467 * order packets have been received, this array
1468 * will be set to all zero. This structure may be
1469 * in the form of a circular buffer or bit array.
1471 * Last Rcvd : This is the last TSN received in
1472 * TSN : sequence. This value is set initially by
1473 * : taking the peer's Initial TSN, received in
1474 * : the INIT or INIT ACK chunk, and subtracting
1477 * Throughout most of the specification this is called the
1478 * "Cumulative TSN ACK Point". In this case, we
1479 * ignore the advice in 12.2 in favour of the term
1480 * used in the bulk of the text. This value is hidden
1481 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1483 struct sctp_tsnmap tsn_map;
1484 __u8 _map[sctp_tsnmap_storage_size(SCTP_TSN_MAP_SIZE)];
1486 /* Ack State : This flag indicates if the next received
1487 * : packet is to be responded to with a
1488 * : SACK. This is initializedto 0. When a packet
1489 * : is received it is incremented. If this value
1490 * : reaches 2 or more, a SACK is sent and the
1491 * : value is reset to 0. Note: This is used only
1492 * : when no DATA chunks are received out of
1493 * : order. When DATA chunks are out of order,
1494 * : SACK's are not delayed (see Section 6).
1496 __u8 sack_needed; /* Do we need to sack the peer? */
1498 /* These are capabilities which our peer advertised. */
1499 __u8 ecn_capable; /* Can peer do ECN? */
1500 __u8 ipv4_address; /* Peer understands IPv4 addresses? */
1501 __u8 ipv6_address; /* Peer understands IPv6 addresses? */
1502 __u8 hostname_address;/* Peer understands DNS addresses? */
1503 __u8 asconf_capable; /* Does peer support ADDIP? */
1504 __u8 prsctp_capable; /* Can peer do PR-SCTP? */
1506 __u32 adaption_ind; /* Adaption Code point. */
1508 /* This mask is used to disable sending the ASCONF chunk
1509 * with specified parameter to peer.
1511 __be16 addip_disabled_mask;
1513 struct sctp_inithdr i;
1517 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1518 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1519 * Initial TSN Value minus 1
1524 /* State : A state variable indicating what state the
1525 * : association is in, i.e. COOKIE-WAIT,
1526 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1527 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1529 * Note: No "CLOSED" state is illustrated since if a
1530 * association is "CLOSED" its TCB SHOULD be removed.
1532 * In this implementation we DO have a CLOSED
1533 * state which is used during initiation and shutdown.
1535 * State takes values from SCTP_STATE_*.
1539 /* The cookie life I award for any cookie. */
1540 struct timeval cookie_life;
1542 /* Overall : The overall association error count.
1543 * Error Count : [Clear this any time I get something.]
1545 int overall_error_count;
1547 /* These are the association's initial, max, and min RTO values.
1548 * These values will be initialized by system defaults, but can
1549 * be modified via the SCTP_RTOINFO socket option.
1551 unsigned long rto_initial;
1552 unsigned long rto_max;
1553 unsigned long rto_min;
1555 /* Maximum number of new data packets that can be sent in a burst. */
1558 /* This is the max_retrans value for the association. This value will
1559 * be initialized initialized from system defaults, but can be
1560 * modified by the SCTP_ASSOCINFO socket option.
1564 /* Maximum number of times the endpoint will retransmit INIT */
1565 __u16 max_init_attempts;
1567 /* How many times have we resent an INIT? */
1570 /* The largest timeout or RTO value to use in attempting an INIT */
1571 unsigned long max_init_timeo;
1573 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1574 * the destination address every heartbeat interval. This value
1575 * will be inherited by all new transports.
1577 unsigned long hbinterval;
1579 /* This is the max_retrans value for new transports in the
1584 /* Association : The smallest PMTU discovered for all of the
1585 * PMTU : peer's transport addresses.
1589 /* Flags controling Heartbeat, SACK delay, and Path MTU Discovery. */
1592 /* SACK delay timeout */
1593 unsigned long sackdelay;
1596 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES];
1597 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1599 /* Transport to which SHUTDOWN chunk was last sent. */
1600 struct sctp_transport *shutdown_last_sent_to;
1602 /* Transport to which INIT chunk was last sent. */
1603 struct sctp_transport *init_last_sent_to;
1605 /* Next TSN : The next TSN number to be assigned to a new
1606 * : DATA chunk. This is sent in the INIT or INIT
1607 * : ACK chunk to the peer and incremented each
1608 * : time a DATA chunk is assigned a TSN
1609 * : (normally just prior to transmit or during
1615 * Last Rcvd : This is the last TSN received in sequence. This value
1616 * TSN : is set initially by taking the peer's Initial TSN,
1617 * : received in the INIT or INIT ACK chunk, and
1618 * : subtracting one from it.
1620 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1623 __u32 ctsn_ack_point;
1625 /* PR-SCTP Advanced.Peer.Ack.Point */
1626 __u32 adv_peer_ack_point;
1628 /* Highest TSN that is acknowledged by incoming SACKs. */
1629 __u32 highest_sacked;
1631 /* The number of unacknowledged data chunks. Reported through
1632 * the SCTP_STATUS sockopt.
1636 /* This is the association's receive buffer space. This value is used
1637 * to set a_rwnd field in an INIT or a SACK chunk.
1641 /* This is the last advertised value of rwnd over a SACK chunk. */
1644 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1645 * to slop over a maximum of the association's frag_point.
1649 /* This is the sndbuf size in use for the association.
1650 * This corresponds to the sndbuf size for the association,
1651 * as specified in the sk->sndbuf.
1655 /* This is the amount of memory that this association has allocated
1656 * in the receive path at any given time.
1658 atomic_t rmem_alloc;
1660 /* This is the wait queue head for send requests waiting on
1661 * the association sndbuf space.
1663 wait_queue_head_t wait;
1665 /* The message size at which SCTP fragmentation will occur. */
1668 /* Counter used to count INIT errors. */
1669 int init_err_counter;
1671 /* Count the number of INIT cycles (for doubling timeout). */
1674 /* Default send parameters. */
1675 __u16 default_stream;
1676 __u16 default_flags;
1678 __u32 default_context;
1679 __u32 default_timetolive;
1681 /* This tracks outbound ssn for a given stream. */
1682 struct sctp_ssnmap *ssnmap;
1684 /* All outbound chunks go through this structure. */
1685 struct sctp_outq outqueue;
1687 /* A smart pipe that will handle reordering and fragmentation,
1688 * as well as handle passing events up to the ULP.
1690 struct sctp_ulpq ulpq;
1692 /* Last TSN that caused an ECNE Chunk to be sent. */
1693 __u32 last_ecne_tsn;
1695 /* Last TSN that caused a CWR Chunk to be sent. */
1698 /* How many duplicated TSNs have we seen? */
1701 /* Number of seconds of idle time before an association is closed.
1702 * In the association context, this is really used as a boolean
1703 * since the real timeout is stored in the timeouts array
1707 /* These are to support
1708 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1709 * and Enforcement of Flow and Message Limits"
1710 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1711 * or "ADDIP" for short.
1716 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1718 * R1) One and only one ASCONF Chunk MAY be in transit and
1719 * unacknowledged at any one time. If a sender, after sending
1720 * an ASCONF chunk, decides it needs to transfer another
1721 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1722 * returns from the previous ASCONF Chunk before sending a
1723 * subsequent ASCONF. Note this restriction binds each side,
1724 * so at any time two ASCONF may be in-transit on any given
1725 * association (one sent from each endpoint).
1727 * [This is our one-and-only-one ASCONF in flight. If we do
1728 * not have an ASCONF in flight, this is NULL.]
1730 struct sctp_chunk *addip_last_asconf;
1732 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1734 * IMPLEMENTATION NOTE: As an optimization a receiver may wish
1735 * to save the last ASCONF-ACK for some predetermined period
1736 * of time and instead of re-processing the ASCONF (with the
1737 * same serial number) it may just re-transmit the
1738 * ASCONF-ACK. It may wish to use the arrival of a new serial
1739 * number to discard the previously saved ASCONF-ACK or any
1740 * other means it may choose to expire the saved ASCONF-ACK.
1742 * [This is our saved ASCONF-ACK. We invalidate it when a new
1743 * ASCONF serial number arrives.]
1745 struct sctp_chunk *addip_last_asconf_ack;
1747 /* These ASCONF chunks are waiting to be sent.
1749 * These chunaks can't be pushed to outqueue until receiving
1750 * ASCONF_ACK for the previous ASCONF indicated by
1751 * addip_last_asconf, so as to guarantee that only one ASCONF
1752 * is in flight at any time.
1754 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1756 * In defining the ASCONF Chunk transfer procedures, it is
1757 * essential that these transfers MUST NOT cause congestion
1758 * within the network. To achieve this, we place these
1759 * restrictions on the transfer of ASCONF Chunks:
1761 * R1) One and only one ASCONF Chunk MAY be in transit and
1762 * unacknowledged at any one time. If a sender, after sending
1763 * an ASCONF chunk, decides it needs to transfer another
1764 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1765 * returns from the previous ASCONF Chunk before sending a
1766 * subsequent ASCONF. Note this restriction binds each side,
1767 * so at any time two ASCONF may be in-transit on any given
1768 * association (one sent from each endpoint).
1771 * [I really think this is EXACTLY the sort of intelligence
1772 * which already resides in sctp_outq. Please move this
1773 * queue and its supporting logic down there. --piggy]
1775 struct list_head addip_chunk_list;
1777 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1779 * A2) A serial number should be assigned to the Chunk. The
1780 * serial number SHOULD be a monotonically increasing
1781 * number. The serial number SHOULD be initialized at
1782 * the start of the association to the same value as the
1783 * Initial TSN and every time a new ASCONF chunk is created
1784 * it is incremented by one after assigning the serial number
1785 * to the newly created chunk.
1788 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
1790 * Serial Number : 32 bits (unsigned integer)
1792 * This value represents a Serial Number for the ASCONF
1793 * Chunk. The valid range of Serial Number is from 0 to
1794 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
1795 * after reaching 4294967295.
1799 /* Need to send an ECNE Chunk? */
1802 /* Is it a temporary association? */
1807 /* An eyecatcher for determining if we are really looking at an
1808 * association data structure.
1811 SCTP_ASSOC_EYECATCHER = 0xa550c123,
1814 /* Recover the outter association structure. */
1815 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
1817 struct sctp_association *asoc;
1819 asoc = container_of(base, struct sctp_association, base);
1823 /* These are function signatures for manipulating associations. */
1826 struct sctp_association *
1827 sctp_association_new(const struct sctp_endpoint *, const struct sock *,
1828 sctp_scope_t scope, gfp_t gfp);
1829 void sctp_association_free(struct sctp_association *);
1830 void sctp_association_put(struct sctp_association *);
1831 void sctp_association_hold(struct sctp_association *);
1833 struct sctp_transport *sctp_assoc_choose_init_transport(
1834 struct sctp_association *);
1835 struct sctp_transport *sctp_assoc_choose_shutdown_transport(
1836 struct sctp_association *);
1837 void sctp_assoc_update_retran_path(struct sctp_association *);
1838 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
1839 const union sctp_addr *);
1840 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1841 const union sctp_addr *laddr);
1842 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
1843 const union sctp_addr *address,
1845 const int peer_state);
1846 void sctp_assoc_del_peer(struct sctp_association *asoc,
1847 const union sctp_addr *addr);
1848 void sctp_assoc_rm_peer(struct sctp_association *asoc,
1849 struct sctp_transport *peer);
1850 void sctp_assoc_control_transport(struct sctp_association *,
1851 struct sctp_transport *,
1852 sctp_transport_cmd_t, sctp_sn_error_t);
1853 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
1854 struct sctp_transport *sctp_assoc_is_match(struct sctp_association *,
1855 const union sctp_addr *,
1856 const union sctp_addr *);
1857 void sctp_assoc_migrate(struct sctp_association *, struct sock *);
1858 void sctp_assoc_update(struct sctp_association *old,
1859 struct sctp_association *new);
1861 __u32 sctp_association_get_next_tsn(struct sctp_association *);
1863 void sctp_assoc_sync_pmtu(struct sctp_association *);
1864 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned);
1865 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned);
1866 void sctp_assoc_set_primary(struct sctp_association *,
1867 struct sctp_transport *);
1868 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *,
1870 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
1871 struct sctp_cookie*,
1874 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1875 const union sctp_addr *ss2);
1876 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
1878 /* A convenience structure to parse out SCTP specific CMSGs. */
1879 typedef struct sctp_cmsgs {
1880 struct sctp_initmsg *init;
1881 struct sctp_sndrcvinfo *info;
1884 /* Structure for tracking memory objects */
1888 } sctp_dbg_objcnt_entry_t;
1890 #endif /* __sctp_structs_h__ */