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;
93 #include <net/sctp/tsnmap.h>
94 #include <net/sctp/ulpevent.h>
95 #include <net/sctp/ulpqueue.h>
97 /* Structures useful for managing bind/connect. */
99 struct sctp_bind_bucket {
101 unsigned short fastreuse;
102 struct sctp_bind_bucket *next;
103 struct sctp_bind_bucket **pprev;
104 struct hlist_head owner;
107 struct sctp_bind_hashbucket {
109 struct sctp_bind_bucket *chain;
112 /* Used for hashing all associations. */
113 struct sctp_hashbucket {
115 struct sctp_ep_common *chain;
116 } __attribute__((__aligned__(8)));
119 /* The SCTP globals structure. */
120 extern struct sctp_globals {
121 /* RFC2960 Section 14. Suggested SCTP Protocol Parameter Values
123 * The following protocol parameters are RECOMMENDED:
125 * RTO.Initial - 3 seconds
127 * RTO.Max - 60 seconds
128 * RTO.Alpha - 1/8 (3 when converted to right shifts.)
129 * RTO.Beta - 1/4 (2 when converted to right shifts.)
131 unsigned int rto_initial;
132 unsigned int rto_min;
133 unsigned int rto_max;
135 /* Note: rto_alpha and rto_beta are really defined as inverse
136 * powers of two to facilitate integer operations.
144 /* Whether Cookie Preservative is enabled(1) or not(0) */
145 int cookie_preserve_enable;
147 /* Valid.Cookie.Life - 60 seconds */
148 unsigned int valid_cookie_life;
150 /* Delayed SACK timeout 200ms default*/
151 unsigned int sack_timeout;
153 /* HB.interval - 30 seconds */
154 unsigned int hb_interval;
156 /* Association.Max.Retrans - 10 attempts
157 * Path.Max.Retrans - 5 attempts (per destination address)
158 * Max.Init.Retransmits - 8 attempts
160 int max_retrans_association;
161 int max_retrans_path;
162 int max_retrans_init;
165 * Policy for preforming sctp/socket accounting
166 * 0 - do socket level accounting, all assocs share sk_sndbuf
167 * 1 - do sctp accounting, each asoc may use sk_sndbuf bytes
172 * Policy for preforming sctp/socket accounting
173 * 0 - do socket level accounting, all assocs share sk_rcvbuf
174 * 1 - do sctp accounting, each asoc may use sk_rcvbuf bytes
178 /* The following variables are implementation specific. */
180 /* Default initialization values to be applied to new associations. */
182 __u16 max_outstreams;
184 /* This is a list of groups of functions for each address
185 * family that we support.
187 struct list_head address_families;
189 /* This is the hash of all endpoints. */
191 struct sctp_hashbucket *ep_hashtable;
193 /* This is the hash of all associations. */
195 struct sctp_hashbucket *assoc_hashtable;
197 /* This is the sctp port control hash. */
200 spinlock_t port_alloc_lock; /* Protects port_rover. */
201 struct sctp_bind_hashbucket *port_hashtable;
203 /* This is the global local address list.
204 * We actively maintain this complete list of addresses on
205 * the system by catching address add/delete events.
207 * It is a list of sctp_sockaddr_entry.
209 struct list_head local_addr_list;
211 /* Flag to indicate if addip is enabled. */
214 /* Flag to indicate if PR-SCTP is enabled. */
218 #define sctp_rto_initial (sctp_globals.rto_initial)
219 #define sctp_rto_min (sctp_globals.rto_min)
220 #define sctp_rto_max (sctp_globals.rto_max)
221 #define sctp_rto_alpha (sctp_globals.rto_alpha)
222 #define sctp_rto_beta (sctp_globals.rto_beta)
223 #define sctp_max_burst (sctp_globals.max_burst)
224 #define sctp_valid_cookie_life (sctp_globals.valid_cookie_life)
225 #define sctp_cookie_preserve_enable (sctp_globals.cookie_preserve_enable)
226 #define sctp_max_retrans_association (sctp_globals.max_retrans_association)
227 #define sctp_sndbuf_policy (sctp_globals.sndbuf_policy)
228 #define sctp_rcvbuf_policy (sctp_globals.rcvbuf_policy)
229 #define sctp_max_retrans_path (sctp_globals.max_retrans_path)
230 #define sctp_max_retrans_init (sctp_globals.max_retrans_init)
231 #define sctp_sack_timeout (sctp_globals.sack_timeout)
232 #define sctp_hb_interval (sctp_globals.hb_interval)
233 #define sctp_max_instreams (sctp_globals.max_instreams)
234 #define sctp_max_outstreams (sctp_globals.max_outstreams)
235 #define sctp_address_families (sctp_globals.address_families)
236 #define sctp_ep_hashsize (sctp_globals.ep_hashsize)
237 #define sctp_ep_hashtable (sctp_globals.ep_hashtable)
238 #define sctp_assoc_hashsize (sctp_globals.assoc_hashsize)
239 #define sctp_assoc_hashtable (sctp_globals.assoc_hashtable)
240 #define sctp_port_hashsize (sctp_globals.port_hashsize)
241 #define sctp_port_rover (sctp_globals.port_rover)
242 #define sctp_port_alloc_lock (sctp_globals.port_alloc_lock)
243 #define sctp_port_hashtable (sctp_globals.port_hashtable)
244 #define sctp_local_addr_list (sctp_globals.local_addr_list)
245 #define sctp_addip_enable (sctp_globals.addip_enable)
246 #define sctp_prsctp_enable (sctp_globals.prsctp_enable)
248 /* SCTP Socket type: UDP or TCP style. */
251 SCTP_SOCKET_UDP_HIGH_BANDWIDTH,
253 } sctp_socket_type_t;
255 /* Per socket SCTP information. */
257 /* inet_sock has to be the first member of sctp_sock */
258 struct inet_sock inet;
259 /* What kind of a socket is this? */
260 sctp_socket_type_t type;
262 /* PF_ family specific functions. */
265 /* Access to HMAC transform. */
266 struct crypto_hash *hmac;
268 /* What is our base endpointer? */
269 struct sctp_endpoint *ep;
271 struct sctp_bind_bucket *bind_hash;
272 /* Various Socket Options. */
273 __u16 default_stream;
276 __u32 default_context;
277 __u32 default_timetolive;
279 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
280 * the destination address every heartbeat interval. This value
281 * will be inherited by all new associations.
285 /* This is the max_retrans value for new associations. */
288 /* The initial Path MTU to use for new associations. */
291 /* The default SACK delay timeout for new associations. */
294 /* Flags controling Heartbeat, SACK delay, and Path MTU Discovery. */
297 struct sctp_initmsg initmsg;
298 struct sctp_rtoinfo rtoinfo;
299 struct sctp_paddrparams paddrparam;
300 struct sctp_event_subscribe subscribe;
301 struct sctp_assocparams assocparams;
305 __u8 disable_fragments;
310 /* Receive to here while partial delivery is in effect. */
311 struct sk_buff_head pd_lobby;
314 static inline struct sctp_sock *sctp_sk(const struct sock *sk)
316 return (struct sctp_sock *)sk;
319 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
321 return (struct sock *)sp;
324 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
326 struct sctp_sock sctp;
327 struct ipv6_pinfo inet6;
329 #endif /* CONFIG_IPV6 */
332 /* This is our APPLICATION-SPECIFIC state cookie.
333 * THIS IS NOT DICTATED BY THE SPECIFICATION.
335 /* These are the parts of an association which we send in the cookie.
336 * Most of these are straight out of:
337 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
343 /* My : Tag expected in every inbound packet and sent
344 * Verification: in the INIT or INIT ACK chunk.
349 /* Peer's : Tag expected in every outbound packet except
350 * Verification: in the INIT chunk.
355 /* The rest of these are not from the spec, but really need to
359 /* My Tie Tag : Assist in discovering a restarting association. */
362 /* Peer's Tie Tag: Assist in discovering a restarting association. */
365 /* When does this cookie expire? */
366 struct timeval expiration;
368 /* Number of inbound/outbound streams which are set
369 * and negotiated during the INIT process.
371 __u16 sinit_num_ostreams;
372 __u16 sinit_max_instreams;
374 /* This is the first sequence number I used. */
377 /* This holds the originating address of the INIT packet. */
378 union sctp_addr peer_addr;
381 * Include the source port of the INIT-ACK
387 /* Padding for future use */
393 /* This is a shim for my peer's INIT packet, followed by
394 * a copy of the raw address list of the association.
395 * The length of the raw address list is saved in the
396 * raw_addr_list_len field, which will be used at the time when
397 * the association TCB is re-constructed from the cookie.
399 __u32 raw_addr_list_len;
400 struct sctp_init_chunk peer_init[0];
404 /* The format of our cookie that we send to our peer. */
405 struct sctp_signed_cookie {
406 __u8 signature[SCTP_SECRET_SIZE];
407 __u32 __pad; /* force sctp_cookie alignment to 64 bits */
408 struct sctp_cookie c;
409 } __attribute__((packed));
411 /* This is another convenience type to allocate memory for address
412 * params for the maximum size and pass such structures around
415 union sctp_addr_param {
416 struct sctp_ipv4addr_param v4;
417 struct sctp_ipv6addr_param v6;
420 /* A convenience type to allow walking through the various
421 * parameters and avoid casting all over the place.
425 struct sctp_paramhdr *p;
426 struct sctp_cookie_preserve_param *life;
427 struct sctp_hostname_param *dns;
428 struct sctp_cookie_param *cookie;
429 struct sctp_supported_addrs_param *sat;
430 struct sctp_ipv4addr_param *v4;
431 struct sctp_ipv6addr_param *v6;
432 union sctp_addr_param *addr;
433 struct sctp_adaption_ind_param *aind;
436 /* RFC 2960. Section 3.3.5 Heartbeat.
437 * Heartbeat Information: variable length
438 * The Sender-specific Heartbeat Info field should normally include
439 * information about the sender's current time when this HEARTBEAT
440 * chunk is sent and the destination transport address to which this
441 * HEARTBEAT is sent (see Section 8.3).
443 typedef struct sctp_sender_hb_info {
444 struct sctp_paramhdr param_hdr;
445 union sctp_addr daddr;
446 unsigned long sent_at;
448 } __attribute__((packed)) sctp_sender_hb_info_t;
451 * RFC 2960 1.3.2 Sequenced Delivery within Streams
453 * The term "stream" is used in SCTP to refer to a sequence of user
454 * messages that are to be delivered to the upper-layer protocol in
455 * order with respect to other messages within the same stream. This is
456 * in contrast to its usage in TCP, where it refers to a sequence of
457 * bytes (in this document a byte is assumed to be eight bits).
460 * This is the structure we use to track both our outbound and inbound
461 * SSN, or Stream Sequence Numbers.
470 struct sctp_stream in;
471 struct sctp_stream out;
475 struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out,
477 void sctp_ssnmap_free(struct sctp_ssnmap *map);
478 void sctp_ssnmap_clear(struct sctp_ssnmap *map);
480 /* What is the current SSN number for this stream? */
481 static inline __u16 sctp_ssn_peek(struct sctp_stream *stream, __u16 id)
483 return stream->ssn[id];
486 /* Return the next SSN number for this stream. */
487 static inline __u16 sctp_ssn_next(struct sctp_stream *stream, __u16 id)
489 return stream->ssn[id]++;
492 /* Skip over this ssn and all below. */
493 static inline void sctp_ssn_skip(struct sctp_stream *stream, __u16 id,
496 stream->ssn[id] = ssn+1;
500 * Pointers to address related SCTP functions.
501 * (i.e. things that depend on the address family.)
504 int (*sctp_xmit) (struct sk_buff *skb,
505 struct sctp_transport *,
507 int (*setsockopt) (struct sock *sk,
512 int (*getsockopt) (struct sock *sk,
517 int (*compat_setsockopt) (struct sock *sk,
522 int (*compat_getsockopt) (struct sock *sk,
527 struct dst_entry *(*get_dst) (struct sctp_association *asoc,
528 union sctp_addr *daddr,
529 union sctp_addr *saddr);
530 void (*get_saddr) (struct sctp_association *asoc,
531 struct dst_entry *dst,
532 union sctp_addr *daddr,
533 union sctp_addr *saddr);
534 void (*copy_addrlist) (struct list_head *,
535 struct net_device *);
536 void (*dst_saddr) (union sctp_addr *saddr,
537 struct dst_entry *dst,
539 int (*cmp_addr) (const union sctp_addr *addr1,
540 const union sctp_addr *addr2);
541 void (*addr_copy) (union sctp_addr *dst,
542 union sctp_addr *src);
543 void (*from_skb) (union sctp_addr *,
546 void (*from_sk) (union sctp_addr *,
548 void (*to_sk_saddr) (union sctp_addr *,
550 void (*to_sk_daddr) (union sctp_addr *,
552 void (*from_addr_param) (union sctp_addr *,
553 union sctp_addr_param *,
554 __be16 port, int iif);
555 int (*to_addr_param) (const union sctp_addr *,
556 union sctp_addr_param *);
557 int (*addr_valid) (union sctp_addr *,
559 const struct sk_buff *);
560 sctp_scope_t (*scope) (union sctp_addr *);
561 void (*inaddr_any) (union sctp_addr *, __be16);
562 int (*is_any) (const union sctp_addr *);
563 int (*available) (union sctp_addr *,
565 int (*skb_iif) (const struct sk_buff *sk);
566 int (*is_ce) (const struct sk_buff *sk);
567 void (*seq_dump_addr)(struct seq_file *seq,
568 union sctp_addr *addr);
569 __u16 net_header_len;
571 sa_family_t sa_family;
572 struct list_head list;
575 struct sctp_af *sctp_get_af_specific(sa_family_t);
576 int sctp_register_af(struct sctp_af *);
578 /* Protocol family functions. */
580 void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
581 void (*skb_msgname) (struct sk_buff *, char *, int *);
582 int (*af_supported) (sa_family_t, struct sctp_sock *);
583 int (*cmp_addr) (const union sctp_addr *,
584 const union sctp_addr *,
586 int (*bind_verify) (struct sctp_sock *, union sctp_addr *);
587 int (*send_verify) (struct sctp_sock *, union sctp_addr *);
588 int (*supported_addrs)(const struct sctp_sock *, __be16 *);
589 struct sock *(*create_accept_sk) (struct sock *sk,
590 struct sctp_association *asoc);
591 void (*addr_v4map) (struct sctp_sock *, union sctp_addr *);
596 /* Structure to track chunk fragments that have been acked, but peer
597 * fragments of the same message have not.
599 struct sctp_datamsg {
600 /* Chunks waiting to be submitted to lower layer. */
601 struct list_head chunks;
602 /* Chunks that have been transmitted. */
603 struct list_head track;
604 /* Reference counting. */
606 /* When is this message no longer interesting to the peer? */
607 unsigned long expires_at;
608 /* Did the messenge fail to send? */
611 /* Control whether chunks from this message can be abandoned. */
615 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
616 struct sctp_sndrcvinfo *,
617 struct msghdr *, int len);
618 void sctp_datamsg_put(struct sctp_datamsg *);
619 void sctp_datamsg_free(struct sctp_datamsg *);
620 void sctp_datamsg_track(struct sctp_chunk *);
621 void sctp_chunk_fail(struct sctp_chunk *, int error);
622 int sctp_chunk_abandoned(struct sctp_chunk *);
624 /* RFC2960 1.4 Key Terms
626 * o Chunk: A unit of information within an SCTP packet, consisting of
627 * a chunk header and chunk-specific content.
629 * As a matter of convenience, we remember the SCTP common header for
630 * each chunk as well as a few other header pointers...
633 struct list_head list;
637 /* This is our link to the per-transport transmitted list. */
638 struct list_head transmitted_list;
640 /* This field is used by chunks that hold fragmented data.
641 * For the first fragment this is the list that holds the rest of
642 * fragments. For the remaining fragments, this is the link to the
643 * frag_list maintained in the first fragment.
645 struct list_head frag_list;
647 /* This points to the sk_buff containing the actual data. */
650 /* These are the SCTP headers by reverse order in a packet.
651 * Note that some of these may happen more than once. In that
652 * case, we point at the "current" one, whatever that means
653 * for that level of header.
656 /* We point this at the FIRST TLV parameter to chunk_hdr. */
657 union sctp_params param_hdr;
660 struct sctp_datahdr *data_hdr;
661 struct sctp_inithdr *init_hdr;
662 struct sctp_sackhdr *sack_hdr;
663 struct sctp_heartbeathdr *hb_hdr;
664 struct sctp_sender_hb_info *hbs_hdr;
665 struct sctp_shutdownhdr *shutdown_hdr;
666 struct sctp_signed_cookie *cookie_hdr;
667 struct sctp_ecnehdr *ecne_hdr;
668 struct sctp_cwrhdr *ecn_cwr_hdr;
669 struct sctp_errhdr *err_hdr;
670 struct sctp_addiphdr *addip_hdr;
671 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
676 struct sctp_chunkhdr *chunk_hdr;
677 struct sctphdr *sctp_hdr;
679 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
680 struct sctp_sndrcvinfo sinfo;
682 /* Which association does this belong to? */
683 struct sctp_association *asoc;
685 /* What endpoint received this chunk? */
686 struct sctp_ep_common *rcvr;
688 /* We fill this in if we are calculating RTT. */
689 unsigned long sent_at;
691 /* What is the origin IP address for this chunk? */
692 union sctp_addr source;
693 /* Destination address for this chunk. */
694 union sctp_addr dest;
696 /* For outbound message, track all fragments for SEND_FAILED. */
697 struct sctp_datamsg *msg;
699 /* For an inbound chunk, this tells us where it came from.
700 * For an outbound chunk, it tells us where we'd like it to
701 * go. It is NULL if we have no preference.
703 struct sctp_transport *transport;
705 __u8 rtt_in_progress; /* Is this chunk used for RTT calculation? */
706 __u8 resent; /* Has this chunk ever been retransmitted. */
707 __u8 has_tsn; /* Does this chunk have a TSN yet? */
708 __u8 has_ssn; /* Does this chunk have a SSN yet? */
709 __u8 singleton; /* Was this the only chunk in the packet? */
710 __u8 end_of_packet; /* Was this the last chunk in the packet? */
711 __u8 ecn_ce_done; /* Have we processed the ECN CE bit? */
712 __u8 pdiscard; /* Discard the whole packet now? */
713 __u8 tsn_gap_acked; /* Is this chunk acked by a GAP ACK? */
714 __s8 fast_retransmit; /* Is this chunk fast retransmitted? */
715 __u8 tsn_missing_report; /* Data chunk missing counter. */
716 __u8 data_accepted; /* At least 1 chunk in this packet accepted */
719 void sctp_chunk_hold(struct sctp_chunk *);
720 void sctp_chunk_put(struct sctp_chunk *);
721 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
723 void sctp_chunk_free(struct sctp_chunk *);
724 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
725 struct sctp_chunk *sctp_chunkify(struct sk_buff *,
726 const struct sctp_association *,
728 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
730 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
732 /* This is a structure for holding either an IPv6 or an IPv4 address. */
733 struct sctp_sockaddr_entry {
734 struct list_head list;
739 typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *);
741 /* This structure holds lists of chunks as we are assembling for
745 /* These are the SCTP header values (host order) for the packet. */
747 __u16 destination_port;
750 /* This contains the payload chunks. */
751 struct list_head chunk_list;
753 /* This is the overhead of the sctp and ip headers. */
755 /* This is the total size of all chunks INCLUDING padding. */
758 /* The packet is destined for this transport address.
759 * The function we finally use to pass down to the next lower
760 * layer lives in the transport structure.
762 struct sctp_transport *transport;
764 /* This packet contains a COOKIE-ECHO chunk. */
765 char has_cookie_echo;
767 /* This packet containsa SACK chunk. */
770 /* SCTP cannot fragment this packet. So let ip fragment it. */
776 struct sctp_packet *sctp_packet_init(struct sctp_packet *,
777 struct sctp_transport *,
778 __u16 sport, __u16 dport);
779 struct sctp_packet *sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
780 sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *,
781 struct sctp_chunk *);
782 sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *,
783 struct sctp_chunk *);
784 int sctp_packet_transmit(struct sctp_packet *);
785 void sctp_packet_free(struct sctp_packet *);
787 static inline int sctp_packet_empty(struct sctp_packet *packet)
789 return (packet->size == packet->overhead);
792 /* This represents a remote transport address.
793 * For local transport addresses, we just use union sctp_addr.
795 * RFC2960 Section 1.4 Key Terms
797 * o Transport address: A Transport Address is traditionally defined
798 * by Network Layer address, Transport Layer protocol and Transport
799 * Layer port number. In the case of SCTP running over IP, a
800 * transport address is defined by the combination of an IP address
801 * and an SCTP port number (where SCTP is the Transport protocol).
803 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
805 * o The sender keeps a separate congestion control parameter set for
806 * each of the destination addresses it can send to (not each
807 * source-destination pair but for each destination). The parameters
808 * should decay if the address is not used for a long enough time
812 struct sctp_transport {
813 /* A list of transports. */
814 struct list_head transports;
816 /* Reference counting. */
820 /* This is the peer's IP address and port. */
821 union sctp_addr ipaddr;
823 /* These are the functions we call to handle LLP stuff. */
824 struct sctp_af *af_specific;
826 /* Which association do we belong to? */
827 struct sctp_association *asoc;
831 * 12.3 Per Transport Address Data
833 * For each destination transport address in the peer's
834 * address list derived from the INIT or INIT ACK chunk, a
835 * number of data elements needs to be maintained including:
837 __u32 rtt; /* This is the most recent RTT. */
839 /* RTO : The current retransmission timeout value. */
842 /* RTTVAR : The current RTT variation. */
845 /* SRTT : The current smoothed round trip time. */
848 /* RTO-Pending : A flag used to track if one of the DATA
849 * chunks sent to this address is currently being
850 * used to compute a RTT. If this flag is 0,
851 * the next DATA chunk sent to this destination
852 * should be used to compute a RTT and this flag
853 * should be set. Every time the RTT
854 * calculation completes (i.e. the DATA chunk
855 * is SACK'd) clear this flag.
860 * These are the congestion stats.
862 /* cwnd : The current congestion window. */
863 __u32 cwnd; /* This is the actual cwnd. */
865 /* ssthresh : The current slow start threshold value. */
868 /* partial : The tracking method for increase of cwnd when in
869 * bytes acked : congestion avoidance mode (see Section 6.2.2)
871 __u32 partial_bytes_acked;
873 /* Data that has been sent, but not acknowledged. */
877 struct dst_entry *dst;
878 /* Source address. */
879 union sctp_addr saddr;
881 /* When was the last time(in jiffies) that a data packet was sent on
882 * this transport? This is used to adjust the cwnd when the transport
885 unsigned long last_time_used;
887 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
888 * the destination address every heartbeat interval.
890 unsigned long hbinterval;
892 /* SACK delay timeout */
893 unsigned long sackdelay;
895 /* When was the last time (in jiffies) that we heard from this
896 * transport? We use this to pick new active and retran paths.
898 unsigned long last_time_heard;
900 /* Last time(in jiffies) when cwnd is reduced due to the congestion
901 * indication based on ECNE chunk.
903 unsigned long last_time_ecne_reduced;
905 /* This is the max_retrans value for the transport and will
906 * be initialized from the assocs value. This can be changed
907 * using SCTP_SET_PEER_ADDR_PARAMS socket option.
911 /* PMTU : The current known path MTU. */
914 /* Flags controling Heartbeat, SACK delay, and Path MTU Discovery. */
917 /* The number of times INIT has been sent on this transport. */
920 /* state : The current state of this destination,
921 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKOWN.
925 /* These are the error stats for this destination. */
927 /* Error count : The current error count for this destination. */
928 unsigned short error_count;
930 /* Per : A timer used by each destination.
934 * [Everywhere else in the text this is called T3-rtx. -ed]
936 struct timer_list T3_rtx_timer;
938 /* Heartbeat timer is per destination. */
939 struct timer_list hb_timer;
941 /* Since we're using per-destination retransmission timers
942 * (see above), we're also using per-destination "transmitted"
943 * queues. This probably ought to be a private struct
944 * accessible only within the outqueue, but it's not, yet.
946 struct list_head transmitted;
948 /* We build bundle-able packets for this transport here. */
949 struct sctp_packet packet;
951 /* This is the list of transports that have chunks to send. */
952 struct list_head send_ready;
954 int malloced; /* Is this structure kfree()able? */
956 /* State information saved for SFR_CACC algorithm. The key
957 * idea in SFR_CACC is to maintain state at the sender on a
958 * per-destination basis when a changeover happens.
959 * char changeover_active;
960 * char cycling_changeover;
961 * __u32 next_tsn_at_change;
962 * char cacc_saw_newack;
965 /* An unsigned integer, which stores the next TSN to be
966 * used by the sender, at the moment of changeover.
968 __u32 next_tsn_at_change;
970 /* A flag which indicates the occurrence of a changeover */
971 char changeover_active;
973 /* A flag which indicates whether the change of primary is
974 * the first switch to this destination address during an
977 char cycling_changeover;
979 /* A temporary flag, which is used during the processing of
980 * a SACK to estimate the causative TSN(s)'s group.
982 char cacc_saw_newack;
985 /* 64-bit random number sent with heartbeat. */
989 struct sctp_transport *sctp_transport_new(const union sctp_addr *,
991 void sctp_transport_set_owner(struct sctp_transport *,
992 struct sctp_association *);
993 void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
995 void sctp_transport_pmtu(struct sctp_transport *);
996 void sctp_transport_free(struct sctp_transport *);
997 void sctp_transport_reset_timers(struct sctp_transport *);
998 void sctp_transport_hold(struct sctp_transport *);
999 void sctp_transport_put(struct sctp_transport *);
1000 void sctp_transport_update_rto(struct sctp_transport *, __u32);
1001 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
1002 void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t);
1003 unsigned long sctp_transport_timeout(struct sctp_transport *);
1006 /* This is the structure we use to queue packets as they come into
1007 * SCTP. We write packets to it and read chunks from it.
1010 /* This is actually a queue of sctp_chunk each
1011 * containing a partially decoded packet.
1013 struct list_head in_chunk_list;
1014 /* This is the packet which is currently off the in queue and is
1015 * being worked on through the inbound chunk processing.
1017 struct sctp_chunk *in_progress;
1019 /* This is the delayed task to finish delivering inbound
1022 struct work_struct immediate;
1024 int malloced; /* Is this structure kfree()able? */
1027 void sctp_inq_init(struct sctp_inq *);
1028 void sctp_inq_free(struct sctp_inq *);
1029 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
1030 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
1031 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t);
1033 /* This is the structure we use to hold outbound chunks. You push
1034 * chunks in and they automatically pop out the other end as bundled
1035 * packets (it calls (*output_handler)()).
1037 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1038 * and 8.2 of the v13 draft.
1040 * It handles retransmissions. The connection to the timeout portion
1041 * of the state machine is through sctp_..._timeout() and timeout_handler.
1043 * If you feed it SACKs, it will eat them.
1045 * If you give it big chunks, it will fragment them.
1047 * It assigns TSN's to data chunks. This happens at the last possible
1048 * instant before transmission.
1050 * When free()'d, it empties itself out via output_handler().
1053 struct sctp_association *asoc;
1055 /* Data pending that has never been transmitted. */
1056 struct list_head out_chunk_list;
1058 unsigned out_qlen; /* Total length of queued data chunks. */
1060 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1063 /* These are control chunks we want to send. */
1064 struct list_head control_chunk_list;
1066 /* These are chunks that have been sacked but are above the
1067 * CTSN, or cumulative tsn ack point.
1069 struct list_head sacked;
1071 /* Put chunks on this list to schedule them for
1074 struct list_head retransmit;
1076 /* Put chunks on this list to save them for FWD TSN processing as
1077 * they were abandoned.
1079 struct list_head abandoned;
1081 /* How many unackd bytes do we have in-flight? */
1082 __u32 outstanding_bytes;
1087 /* Is this structure empty? */
1090 /* Are we kfree()able? */
1094 void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1095 void sctp_outq_teardown(struct sctp_outq *);
1096 void sctp_outq_free(struct sctp_outq*);
1097 int sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk);
1098 int sctp_outq_flush(struct sctp_outq *, int);
1099 int sctp_outq_sack(struct sctp_outq *, struct sctp_sackhdr *);
1100 int sctp_outq_is_empty(const struct sctp_outq *);
1101 void sctp_outq_restart(struct sctp_outq *);
1103 void sctp_retransmit(struct sctp_outq *, struct sctp_transport *,
1104 sctp_retransmit_reason_t);
1105 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1106 int sctp_outq_uncork(struct sctp_outq *);
1107 /* Uncork and flush an outqueue. */
1108 static inline void sctp_outq_cork(struct sctp_outq *q)
1113 /* These bind address data fields common between endpoints and associations */
1114 struct sctp_bind_addr {
1116 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1118 * SCTP Port: The local SCTP port number the endpoint is
1123 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1125 * Address List: The list of IP addresses that this instance
1126 * has bound. This information is passed to one's
1127 * peer(s) in INIT and INIT ACK chunks.
1129 struct list_head address_list;
1131 int malloced; /* Are we kfree()able? */
1134 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1135 void sctp_bind_addr_free(struct sctp_bind_addr *);
1136 int sctp_bind_addr_copy(struct sctp_bind_addr *dest,
1137 const struct sctp_bind_addr *src,
1138 sctp_scope_t scope, gfp_t gfp,
1140 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1141 __u8 use_as_src, gfp_t gfp);
1142 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1143 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1144 struct sctp_sock *);
1145 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp,
1146 const union sctp_addr *addrs,
1148 struct sctp_sock *opt);
1149 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1152 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1153 __u16 port, gfp_t gfp);
1155 sctp_scope_t sctp_scope(const union sctp_addr *);
1156 int sctp_in_scope(const union sctp_addr *addr, const sctp_scope_t scope);
1157 int sctp_is_any(const union sctp_addr *addr);
1158 int sctp_addr_is_valid(const union sctp_addr *addr);
1161 /* What type of endpoint? */
1163 SCTP_EP_TYPE_SOCKET,
1164 SCTP_EP_TYPE_ASSOCIATION,
1165 } sctp_endpoint_type_t;
1168 * A common base class to bridge the implmentation view of a
1169 * socket (usually listening) endpoint versus an association's
1171 * This common structure is useful for several purposes:
1172 * 1) Common interface for lookup routines.
1173 * a) Subfunctions work for either endpoint or association
1174 * b) Single interface to lookup allows hiding the lookup lock rather
1175 * than acquiring it externally.
1176 * 2) Common interface for the inbound chunk handling/state machine.
1177 * 3) Common object handling routines for reference counting, etc.
1178 * 4) Disentangle association lookup from endpoint lookup, where we
1179 * do not have to find our endpoint to find our association.
1183 struct sctp_ep_common {
1184 /* Fields to help us manage our entries in the hash tables. */
1185 struct sctp_ep_common *next;
1186 struct sctp_ep_common **pprev;
1189 /* Runtime type information. What kind of endpoint is this? */
1190 sctp_endpoint_type_t type;
1192 /* Some fields to help us manage this object.
1193 * refcnt - Reference count access to this object.
1194 * dead - Do not attempt to use this object.
1195 * malloced - Do we need to kfree this object?
1201 /* What socket does this endpoint belong to? */
1204 /* This is where we receive inbound chunks. */
1205 struct sctp_inq inqueue;
1207 /* This substructure includes the defining parameters of the
1209 * bind_addr.port is our shared port number.
1210 * bind_addr.address_list is our set of local IP addresses.
1212 struct sctp_bind_addr bind_addr;
1214 /* Protection during address list comparisons. */
1219 /* RFC Section 1.4 Key Terms
1221 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1222 * multi-homed host, an SCTP endpoint is represented to its peers as a
1223 * combination of a set of eligible destination transport addresses to
1224 * which SCTP packets can be sent and a set of eligible source
1225 * transport addresses from which SCTP packets can be received.
1226 * All transport addresses used by an SCTP endpoint must use the
1227 * same port number, but can use multiple IP addresses. A transport
1228 * address used by an SCTP endpoint must not be used by another
1229 * SCTP endpoint. In other words, a transport address is unique
1230 * to an SCTP endpoint.
1232 * From an implementation perspective, each socket has one of these.
1233 * A TCP-style socket will have exactly one association on one of
1234 * these. An UDP-style socket will have multiple associations hanging
1238 struct sctp_endpoint {
1239 /* Common substructure for endpoint and association. */
1240 struct sctp_ep_common base;
1242 /* Associations: A list of current associations and mappings
1243 * to the data consumers for each association. This
1244 * may be in the form of a hash table or other
1245 * implementation dependent structure. The data
1246 * consumers may be process identification
1247 * information such as file descriptors, named pipe
1248 * pointer, or table pointers dependent on how SCTP
1251 /* This is really a list of struct sctp_association entries. */
1252 struct list_head asocs;
1254 /* Secret Key: A secret key used by this endpoint to compute
1255 * the MAC. This SHOULD be a cryptographic quality
1256 * random number with a sufficient length.
1257 * Discussion in [RFC1750] can be helpful in
1258 * selection of the key.
1260 __u8 secret_key[SCTP_HOW_MANY_SECRETS][SCTP_SECRET_SIZE];
1265 /* digest: This is a digest of the sctp cookie. This field is
1266 * only used on the receive path when we try to validate
1267 * that the cookie has not been tampered with. We put
1268 * this here so we pre-allocate this once and can re-use
1273 /* sendbuf acct. policy. */
1274 __u32 sndbuf_policy;
1276 /* rcvbuf acct. policy. */
1277 __u32 rcvbuf_policy;
1280 /* Recover the outter endpoint structure. */
1281 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1283 struct sctp_endpoint *ep;
1285 ep = container_of(base, struct sctp_endpoint, base);
1289 /* These are function signatures for manipulating endpoints. */
1290 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1291 void sctp_endpoint_free(struct sctp_endpoint *);
1292 void sctp_endpoint_put(struct sctp_endpoint *);
1293 void sctp_endpoint_hold(struct sctp_endpoint *);
1294 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1295 struct sctp_association *sctp_endpoint_lookup_assoc(
1296 const struct sctp_endpoint *ep,
1297 const union sctp_addr *paddr,
1298 struct sctp_transport **);
1299 int sctp_endpoint_is_peeled_off(struct sctp_endpoint *,
1300 const union sctp_addr *);
1301 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1302 const union sctp_addr *);
1303 int sctp_has_association(const union sctp_addr *laddr,
1304 const union sctp_addr *paddr);
1306 int sctp_verify_init(const struct sctp_association *asoc, sctp_cid_t,
1307 sctp_init_chunk_t *peer_init, struct sctp_chunk *chunk,
1308 struct sctp_chunk **err_chunk);
1309 int sctp_process_init(struct sctp_association *, sctp_cid_t cid,
1310 const union sctp_addr *peer,
1311 sctp_init_chunk_t *init, gfp_t gfp);
1312 __u32 sctp_generate_tag(const struct sctp_endpoint *);
1313 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
1315 struct sctp_inithdr_host {
1318 __u16 num_outbound_streams;
1319 __u16 num_inbound_streams;
1325 * 12. Recommended Transmission Control Block (TCB) Parameters
1327 * This section details a recommended set of parameters that should
1328 * be contained within the TCB for an implementation. This section is
1329 * for illustrative purposes and should not be deemed as requirements
1330 * on an implementation or as an exhaustive list of all parameters
1331 * inside an SCTP TCB. Each implementation may need its own additional
1332 * parameters for optimization.
1336 /* Here we have information about each individual association. */
1337 struct sctp_association {
1339 /* A base structure common to endpoint and association.
1340 * In this context, it represents the associations's view
1341 * of the local endpoint of the association.
1343 struct sctp_ep_common base;
1345 /* Associations on the same socket. */
1346 struct list_head asocs;
1348 /* association id. */
1349 sctp_assoc_t assoc_id;
1351 /* This is our parent endpoint. */
1352 struct sctp_endpoint *ep;
1354 /* These are those association elements needed in the cookie. */
1355 struct sctp_cookie c;
1357 /* This is all information about our peer. */
1361 * Peer Rwnd : Current calculated value of the peer's rwnd.
1365 /* transport_addr_list
1367 * Peer : A list of SCTP transport addresses that the
1368 * Transport : peer is bound to. This information is derived
1369 * Address : from the INIT or INIT ACK and is used to
1370 * List : associate an inbound packet with a given
1371 * : association. Normally this information is
1372 * : hashed or keyed for quick lookup and access
1374 * : The list is also initialized with the list
1375 * : of addresses passed with the sctp_connectx()
1378 * It is a list of SCTP_transport's.
1380 struct list_head transport_addr_list;
1384 * Peer : A count of the number of peer addresses
1385 * Transport : in the Peer Transport Address List.
1389 __u16 transport_count;
1392 * The transport layer port number.
1398 * Primary : This is the current primary destination
1399 * Path : transport address of the peer endpoint. It
1400 * : may also specify a source transport address
1401 * : on this endpoint.
1403 * All of these paths live on transport_addr_list.
1405 * At the bakeoffs, we discovered that the intent of
1406 * primaryPath is that it only changes when the ULP
1407 * asks to have it changed. We add the activePath to
1408 * designate the connection we are currently using to
1409 * transmit new data and most control chunks.
1411 struct sctp_transport *primary_path;
1413 /* Cache the primary path address here, when we
1414 * need a an address for msg_name.
1416 union sctp_addr primary_addr;
1419 * The path that we are currently using to
1420 * transmit new data and most control chunks.
1422 struct sctp_transport *active_path;
1426 * RFC2960 6.4 Multi-homed SCTP Endpoints
1428 * Furthermore, when its peer is multi-homed, an
1429 * endpoint SHOULD try to retransmit a chunk to an
1430 * active destination transport address that is
1431 * different from the last destination address to
1432 * which the DATA chunk was sent.
1434 struct sctp_transport *retran_path;
1436 /* Pointer to last transport I have sent on. */
1437 struct sctp_transport *last_sent_to;
1439 /* This is the last transport I have received DATA on. */
1440 struct sctp_transport *last_data_from;
1443 * Mapping An array of bits or bytes indicating which out of
1444 * Array order TSN's have been received (relative to the
1445 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1446 * order packets have been received, this array
1447 * will be set to all zero. This structure may be
1448 * in the form of a circular buffer or bit array.
1450 * Last Rcvd : This is the last TSN received in
1451 * TSN : sequence. This value is set initially by
1452 * : taking the peer's Initial TSN, received in
1453 * : the INIT or INIT ACK chunk, and subtracting
1456 * Throughout most of the specification this is called the
1457 * "Cumulative TSN ACK Point". In this case, we
1458 * ignore the advice in 12.2 in favour of the term
1459 * used in the bulk of the text. This value is hidden
1460 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1462 struct sctp_tsnmap tsn_map;
1463 __u8 _map[sctp_tsnmap_storage_size(SCTP_TSN_MAP_SIZE)];
1465 /* Ack State : This flag indicates if the next received
1466 * : packet is to be responded to with a
1467 * : SACK. This is initializedto 0. When a packet
1468 * : is received it is incremented. If this value
1469 * : reaches 2 or more, a SACK is sent and the
1470 * : value is reset to 0. Note: This is used only
1471 * : when no DATA chunks are received out of
1472 * : order. When DATA chunks are out of order,
1473 * : SACK's are not delayed (see Section 6).
1475 __u8 sack_needed; /* Do we need to sack the peer? */
1477 /* These are capabilities which our peer advertised. */
1478 __u8 ecn_capable; /* Can peer do ECN? */
1479 __u8 ipv4_address; /* Peer understands IPv4 addresses? */
1480 __u8 ipv6_address; /* Peer understands IPv6 addresses? */
1481 __u8 hostname_address;/* Peer understands DNS addresses? */
1482 __u8 asconf_capable; /* Does peer support ADDIP? */
1483 __u8 prsctp_capable; /* Can peer do PR-SCTP? */
1485 __u32 adaption_ind; /* Adaption Code point. */
1487 /* This mask is used to disable sending the ASCONF chunk
1488 * with specified parameter to peer.
1490 __be16 addip_disabled_mask;
1492 struct sctp_inithdr_host i;
1496 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1497 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1498 * Initial TSN Value minus 1
1503 /* State : A state variable indicating what state the
1504 * : association is in, i.e. COOKIE-WAIT,
1505 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1506 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1508 * Note: No "CLOSED" state is illustrated since if a
1509 * association is "CLOSED" its TCB SHOULD be removed.
1511 * In this implementation we DO have a CLOSED
1512 * state which is used during initiation and shutdown.
1514 * State takes values from SCTP_STATE_*.
1518 /* The cookie life I award for any cookie. */
1519 struct timeval cookie_life;
1521 /* Overall : The overall association error count.
1522 * Error Count : [Clear this any time I get something.]
1524 int overall_error_count;
1526 /* These are the association's initial, max, and min RTO values.
1527 * These values will be initialized by system defaults, but can
1528 * be modified via the SCTP_RTOINFO socket option.
1530 unsigned long rto_initial;
1531 unsigned long rto_max;
1532 unsigned long rto_min;
1534 /* Maximum number of new data packets that can be sent in a burst. */
1537 /* This is the max_retrans value for the association. This value will
1538 * be initialized initialized from system defaults, but can be
1539 * modified by the SCTP_ASSOCINFO socket option.
1543 /* Maximum number of times the endpoint will retransmit INIT */
1544 __u16 max_init_attempts;
1546 /* How many times have we resent an INIT? */
1549 /* The largest timeout or RTO value to use in attempting an INIT */
1550 unsigned long max_init_timeo;
1552 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1553 * the destination address every heartbeat interval. This value
1554 * will be inherited by all new transports.
1556 unsigned long hbinterval;
1558 /* This is the max_retrans value for new transports in the
1563 /* Association : The smallest PMTU discovered for all of the
1564 * PMTU : peer's transport addresses.
1568 /* Flags controling Heartbeat, SACK delay, and Path MTU Discovery. */
1571 /* SACK delay timeout */
1572 unsigned long sackdelay;
1575 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES];
1576 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1578 /* Transport to which SHUTDOWN chunk was last sent. */
1579 struct sctp_transport *shutdown_last_sent_to;
1581 /* Transport to which INIT chunk was last sent. */
1582 struct sctp_transport *init_last_sent_to;
1584 /* Next TSN : The next TSN number to be assigned to a new
1585 * : DATA chunk. This is sent in the INIT or INIT
1586 * : ACK chunk to the peer and incremented each
1587 * : time a DATA chunk is assigned a TSN
1588 * : (normally just prior to transmit or during
1594 * Last Rcvd : This is the last TSN received in sequence. This value
1595 * TSN : is set initially by taking the peer's Initial TSN,
1596 * : received in the INIT or INIT ACK chunk, and
1597 * : subtracting one from it.
1599 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1602 __u32 ctsn_ack_point;
1604 /* PR-SCTP Advanced.Peer.Ack.Point */
1605 __u32 adv_peer_ack_point;
1607 /* Highest TSN that is acknowledged by incoming SACKs. */
1608 __u32 highest_sacked;
1610 /* The number of unacknowledged data chunks. Reported through
1611 * the SCTP_STATUS sockopt.
1615 /* This is the association's receive buffer space. This value is used
1616 * to set a_rwnd field in an INIT or a SACK chunk.
1620 /* This is the last advertised value of rwnd over a SACK chunk. */
1623 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1624 * to slop over a maximum of the association's frag_point.
1628 /* This is the sndbuf size in use for the association.
1629 * This corresponds to the sndbuf size for the association,
1630 * as specified in the sk->sndbuf.
1634 /* This is the amount of memory that this association has allocated
1635 * in the receive path at any given time.
1637 atomic_t rmem_alloc;
1639 /* This is the wait queue head for send requests waiting on
1640 * the association sndbuf space.
1642 wait_queue_head_t wait;
1644 /* The message size at which SCTP fragmentation will occur. */
1647 /* Counter used to count INIT errors. */
1648 int init_err_counter;
1650 /* Count the number of INIT cycles (for doubling timeout). */
1653 /* Default send parameters. */
1654 __u16 default_stream;
1655 __u16 default_flags;
1657 __u32 default_context;
1658 __u32 default_timetolive;
1660 /* This tracks outbound ssn for a given stream. */
1661 struct sctp_ssnmap *ssnmap;
1663 /* All outbound chunks go through this structure. */
1664 struct sctp_outq outqueue;
1666 /* A smart pipe that will handle reordering and fragmentation,
1667 * as well as handle passing events up to the ULP.
1669 struct sctp_ulpq ulpq;
1671 /* Last TSN that caused an ECNE Chunk to be sent. */
1672 __u32 last_ecne_tsn;
1674 /* Last TSN that caused a CWR Chunk to be sent. */
1677 /* How many duplicated TSNs have we seen? */
1680 /* Number of seconds of idle time before an association is closed.
1681 * In the association context, this is really used as a boolean
1682 * since the real timeout is stored in the timeouts array
1686 /* These are to support
1687 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1688 * and Enforcement of Flow and Message Limits"
1689 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1690 * or "ADDIP" for short.
1695 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1697 * R1) One and only one ASCONF Chunk MAY be in transit and
1698 * unacknowledged at any one time. If a sender, after sending
1699 * an ASCONF chunk, decides it needs to transfer another
1700 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1701 * returns from the previous ASCONF Chunk before sending a
1702 * subsequent ASCONF. Note this restriction binds each side,
1703 * so at any time two ASCONF may be in-transit on any given
1704 * association (one sent from each endpoint).
1706 * [This is our one-and-only-one ASCONF in flight. If we do
1707 * not have an ASCONF in flight, this is NULL.]
1709 struct sctp_chunk *addip_last_asconf;
1711 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1713 * IMPLEMENTATION NOTE: As an optimization a receiver may wish
1714 * to save the last ASCONF-ACK for some predetermined period
1715 * of time and instead of re-processing the ASCONF (with the
1716 * same serial number) it may just re-transmit the
1717 * ASCONF-ACK. It may wish to use the arrival of a new serial
1718 * number to discard the previously saved ASCONF-ACK or any
1719 * other means it may choose to expire the saved ASCONF-ACK.
1721 * [This is our saved ASCONF-ACK. We invalidate it when a new
1722 * ASCONF serial number arrives.]
1724 struct sctp_chunk *addip_last_asconf_ack;
1726 /* These ASCONF chunks are waiting to be sent.
1728 * These chunaks can't be pushed to outqueue until receiving
1729 * ASCONF_ACK for the previous ASCONF indicated by
1730 * addip_last_asconf, so as to guarantee that only one ASCONF
1731 * is in flight at any time.
1733 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1735 * In defining the ASCONF Chunk transfer procedures, it is
1736 * essential that these transfers MUST NOT cause congestion
1737 * within the network. To achieve this, we place these
1738 * restrictions on the transfer of ASCONF Chunks:
1740 * R1) One and only one ASCONF Chunk MAY be in transit and
1741 * unacknowledged at any one time. If a sender, after sending
1742 * an ASCONF chunk, decides it needs to transfer another
1743 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1744 * returns from the previous ASCONF Chunk before sending a
1745 * subsequent ASCONF. Note this restriction binds each side,
1746 * so at any time two ASCONF may be in-transit on any given
1747 * association (one sent from each endpoint).
1750 * [I really think this is EXACTLY the sort of intelligence
1751 * which already resides in sctp_outq. Please move this
1752 * queue and its supporting logic down there. --piggy]
1754 struct list_head addip_chunk_list;
1756 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1758 * A2) A serial number should be assigned to the Chunk. The
1759 * serial number SHOULD be a monotonically increasing
1760 * number. The serial number SHOULD be initialized at
1761 * the start of the association to the same value as the
1762 * Initial TSN and every time a new ASCONF chunk is created
1763 * it is incremented by one after assigning the serial number
1764 * to the newly created chunk.
1767 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
1769 * Serial Number : 32 bits (unsigned integer)
1771 * This value represents a Serial Number for the ASCONF
1772 * Chunk. The valid range of Serial Number is from 0 to
1773 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
1774 * after reaching 4294967295.
1778 /* Need to send an ECNE Chunk? */
1781 /* Is it a temporary association? */
1786 /* An eyecatcher for determining if we are really looking at an
1787 * association data structure.
1790 SCTP_ASSOC_EYECATCHER = 0xa550c123,
1793 /* Recover the outter association structure. */
1794 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
1796 struct sctp_association *asoc;
1798 asoc = container_of(base, struct sctp_association, base);
1802 /* These are function signatures for manipulating associations. */
1805 struct sctp_association *
1806 sctp_association_new(const struct sctp_endpoint *, const struct sock *,
1807 sctp_scope_t scope, gfp_t gfp);
1808 void sctp_association_free(struct sctp_association *);
1809 void sctp_association_put(struct sctp_association *);
1810 void sctp_association_hold(struct sctp_association *);
1812 struct sctp_transport *sctp_assoc_choose_init_transport(
1813 struct sctp_association *);
1814 struct sctp_transport *sctp_assoc_choose_shutdown_transport(
1815 struct sctp_association *);
1816 void sctp_assoc_update_retran_path(struct sctp_association *);
1817 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
1818 const union sctp_addr *);
1819 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1820 const union sctp_addr *laddr);
1821 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
1822 const union sctp_addr *address,
1824 const int peer_state);
1825 void sctp_assoc_del_peer(struct sctp_association *asoc,
1826 const union sctp_addr *addr);
1827 void sctp_assoc_rm_peer(struct sctp_association *asoc,
1828 struct sctp_transport *peer);
1829 void sctp_assoc_control_transport(struct sctp_association *,
1830 struct sctp_transport *,
1831 sctp_transport_cmd_t, sctp_sn_error_t);
1832 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
1833 struct sctp_transport *sctp_assoc_is_match(struct sctp_association *,
1834 const union sctp_addr *,
1835 const union sctp_addr *);
1836 void sctp_assoc_migrate(struct sctp_association *, struct sock *);
1837 void sctp_assoc_update(struct sctp_association *old,
1838 struct sctp_association *new);
1840 __u32 sctp_association_get_next_tsn(struct sctp_association *);
1842 void sctp_assoc_sync_pmtu(struct sctp_association *);
1843 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned);
1844 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned);
1845 void sctp_assoc_set_primary(struct sctp_association *,
1846 struct sctp_transport *);
1847 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *,
1849 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
1850 struct sctp_cookie*,
1853 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1854 const union sctp_addr *ss2);
1855 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
1857 /* A convenience structure to parse out SCTP specific CMSGs. */
1858 typedef struct sctp_cmsgs {
1859 struct sctp_initmsg *init;
1860 struct sctp_sndrcvinfo *info;
1863 /* Structure for tracking memory objects */
1867 } sctp_dbg_objcnt_entry_t;
1869 #endif /* __sctp_structs_h__ */