1 /* SCTP kernel 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 implementation
9 * This SCTP 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 * This SCTP 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. */
67 #include <net/sctp/auth.h> /* We need auth specific structs */
69 /* A convenience structure for handling sockaddr structures.
70 * We should wean ourselves off this.
73 struct sockaddr_in v4;
74 struct sockaddr_in6 v6;
78 /* Forward declarations for data structures. */
81 struct sctp_association;
82 struct sctp_transport;
87 struct sctp_bind_addr;
89 struct sctp_ep_common;
94 #include <net/sctp/tsnmap.h>
95 #include <net/sctp/ulpevent.h>
96 #include <net/sctp/ulpqueue.h>
98 /* Structures useful for managing bind/connect. */
100 struct sctp_bind_bucket {
102 unsigned short fastreuse;
103 struct hlist_node node;
104 struct hlist_head owner;
107 struct sctp_bind_hashbucket {
109 struct hlist_head chain;
112 /* Used for hashing all associations. */
113 struct sctp_hashbucket {
115 struct hlist_head 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. */
199 struct sctp_bind_hashbucket *port_hashtable;
201 /* This is the global local address list.
202 * We actively maintain this complete list of addresses on
203 * the system by catching address add/delete events.
205 * It is a list of sctp_sockaddr_entry.
207 struct list_head local_addr_list;
209 /* Lock that protects the local_addr_list writers */
210 spinlock_t addr_list_lock;
212 /* Flag to indicate if addip is enabled. */
214 int addip_noauth_enable;
216 /* Flag to indicate if PR-SCTP is enabled. */
219 /* Flag to idicate if SCTP-AUTH is enabled */
223 #define sctp_rto_initial (sctp_globals.rto_initial)
224 #define sctp_rto_min (sctp_globals.rto_min)
225 #define sctp_rto_max (sctp_globals.rto_max)
226 #define sctp_rto_alpha (sctp_globals.rto_alpha)
227 #define sctp_rto_beta (sctp_globals.rto_beta)
228 #define sctp_max_burst (sctp_globals.max_burst)
229 #define sctp_valid_cookie_life (sctp_globals.valid_cookie_life)
230 #define sctp_cookie_preserve_enable (sctp_globals.cookie_preserve_enable)
231 #define sctp_max_retrans_association (sctp_globals.max_retrans_association)
232 #define sctp_sndbuf_policy (sctp_globals.sndbuf_policy)
233 #define sctp_rcvbuf_policy (sctp_globals.rcvbuf_policy)
234 #define sctp_max_retrans_path (sctp_globals.max_retrans_path)
235 #define sctp_max_retrans_init (sctp_globals.max_retrans_init)
236 #define sctp_sack_timeout (sctp_globals.sack_timeout)
237 #define sctp_hb_interval (sctp_globals.hb_interval)
238 #define sctp_max_instreams (sctp_globals.max_instreams)
239 #define sctp_max_outstreams (sctp_globals.max_outstreams)
240 #define sctp_address_families (sctp_globals.address_families)
241 #define sctp_ep_hashsize (sctp_globals.ep_hashsize)
242 #define sctp_ep_hashtable (sctp_globals.ep_hashtable)
243 #define sctp_assoc_hashsize (sctp_globals.assoc_hashsize)
244 #define sctp_assoc_hashtable (sctp_globals.assoc_hashtable)
245 #define sctp_port_hashsize (sctp_globals.port_hashsize)
246 #define sctp_port_rover (sctp_globals.port_rover)
247 #define sctp_port_alloc_lock (sctp_globals.port_alloc_lock)
248 #define sctp_port_hashtable (sctp_globals.port_hashtable)
249 #define sctp_local_addr_list (sctp_globals.local_addr_list)
250 #define sctp_local_addr_lock (sctp_globals.addr_list_lock)
251 #define sctp_addip_enable (sctp_globals.addip_enable)
252 #define sctp_addip_noauth (sctp_globals.addip_noauth_enable)
253 #define sctp_prsctp_enable (sctp_globals.prsctp_enable)
254 #define sctp_auth_enable (sctp_globals.auth_enable)
256 /* SCTP Socket type: UDP or TCP style. */
259 SCTP_SOCKET_UDP_HIGH_BANDWIDTH,
261 } sctp_socket_type_t;
263 /* Per socket SCTP information. */
265 /* inet_sock has to be the first member of sctp_sock */
266 struct inet_sock inet;
267 /* What kind of a socket is this? */
268 sctp_socket_type_t type;
270 /* PF_ family specific functions. */
273 /* Access to HMAC transform. */
274 struct crypto_hash *hmac;
276 /* What is our base endpointer? */
277 struct sctp_endpoint *ep;
279 struct sctp_bind_bucket *bind_hash;
280 /* Various Socket Options. */
281 __u16 default_stream;
284 __u32 default_context;
285 __u32 default_timetolive;
286 __u32 default_rcv_context;
289 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
290 * the destination address every heartbeat interval. This value
291 * will be inherited by all new associations.
295 /* This is the max_retrans value for new associations. */
298 /* The initial Path MTU to use for new associations. */
301 /* The default SACK delay timeout for new associations. */
304 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
307 struct sctp_initmsg initmsg;
308 struct sctp_rtoinfo rtoinfo;
309 struct sctp_paddrparams paddrparam;
310 struct sctp_event_subscribe subscribe;
311 struct sctp_assocparams assocparams;
315 __u8 disable_fragments;
317 __u8 frag_interleave;
318 __u32 adaptation_ind;
322 /* Receive to here while partial delivery is in effect. */
323 struct sk_buff_head pd_lobby;
326 static inline struct sctp_sock *sctp_sk(const struct sock *sk)
328 return (struct sctp_sock *)sk;
331 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
333 return (struct sock *)sp;
336 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
338 struct sctp_sock sctp;
339 struct ipv6_pinfo inet6;
341 #endif /* CONFIG_IPV6 */
344 /* This is our APPLICATION-SPECIFIC state cookie.
345 * THIS IS NOT DICTATED BY THE SPECIFICATION.
347 /* These are the parts of an association which we send in the cookie.
348 * Most of these are straight out of:
349 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
355 /* My : Tag expected in every inbound packet and sent
356 * Verification: in the INIT or INIT ACK chunk.
361 /* Peer's : Tag expected in every outbound packet except
362 * Verification: in the INIT chunk.
367 /* The rest of these are not from the spec, but really need to
371 /* My Tie Tag : Assist in discovering a restarting association. */
374 /* Peer's Tie Tag: Assist in discovering a restarting association. */
377 /* When does this cookie expire? */
378 struct timeval expiration;
380 /* Number of inbound/outbound streams which are set
381 * and negotiated during the INIT process.
383 __u16 sinit_num_ostreams;
384 __u16 sinit_max_instreams;
386 /* This is the first sequence number I used. */
389 /* This holds the originating address of the INIT packet. */
390 union sctp_addr peer_addr;
393 * Include the source port of the INIT-ACK
399 /* Padding for future use */
402 __u32 adaptation_ind;
404 __u8 auth_random[sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH];
405 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS + 2];
406 __u8 auth_chunks[sizeof(sctp_paramhdr_t) + SCTP_AUTH_MAX_CHUNKS];
408 /* This is a shim for my peer's INIT packet, followed by
409 * a copy of the raw address list of the association.
410 * The length of the raw address list is saved in the
411 * raw_addr_list_len field, which will be used at the time when
412 * the association TCB is re-constructed from the cookie.
414 __u32 raw_addr_list_len;
415 struct sctp_init_chunk peer_init[0];
419 /* The format of our cookie that we send to our peer. */
420 struct sctp_signed_cookie {
421 __u8 signature[SCTP_SECRET_SIZE];
422 __u32 __pad; /* force sctp_cookie alignment to 64 bits */
423 struct sctp_cookie c;
424 } __attribute__((packed));
426 /* This is another convenience type to allocate memory for address
427 * params for the maximum size and pass such structures around
430 union sctp_addr_param {
431 struct sctp_paramhdr p;
432 struct sctp_ipv4addr_param v4;
433 struct sctp_ipv6addr_param v6;
436 /* A convenience type to allow walking through the various
437 * parameters and avoid casting all over the place.
441 struct sctp_paramhdr *p;
442 struct sctp_cookie_preserve_param *life;
443 struct sctp_hostname_param *dns;
444 struct sctp_cookie_param *cookie;
445 struct sctp_supported_addrs_param *sat;
446 struct sctp_ipv4addr_param *v4;
447 struct sctp_ipv6addr_param *v6;
448 union sctp_addr_param *addr;
449 struct sctp_adaptation_ind_param *aind;
450 struct sctp_supported_ext_param *ext;
451 struct sctp_random_param *random;
452 struct sctp_chunks_param *chunks;
453 struct sctp_hmac_algo_param *hmac_algo;
454 struct sctp_addip_param *addip;
457 /* RFC 2960. Section 3.3.5 Heartbeat.
458 * Heartbeat Information: variable length
459 * The Sender-specific Heartbeat Info field should normally include
460 * information about the sender's current time when this HEARTBEAT
461 * chunk is sent and the destination transport address to which this
462 * HEARTBEAT is sent (see Section 8.3).
464 typedef struct sctp_sender_hb_info {
465 struct sctp_paramhdr param_hdr;
466 union sctp_addr daddr;
467 unsigned long sent_at;
469 } __attribute__((packed)) sctp_sender_hb_info_t;
472 * RFC 2960 1.3.2 Sequenced Delivery within Streams
474 * The term "stream" is used in SCTP to refer to a sequence of user
475 * messages that are to be delivered to the upper-layer protocol in
476 * order with respect to other messages within the same stream. This is
477 * in contrast to its usage in TCP, where it refers to a sequence of
478 * bytes (in this document a byte is assumed to be eight bits).
481 * This is the structure we use to track both our outbound and inbound
482 * SSN, or Stream Sequence Numbers.
491 struct sctp_stream in;
492 struct sctp_stream out;
496 struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out,
498 void sctp_ssnmap_free(struct sctp_ssnmap *map);
499 void sctp_ssnmap_clear(struct sctp_ssnmap *map);
501 /* What is the current SSN number for this stream? */
502 static inline __u16 sctp_ssn_peek(struct sctp_stream *stream, __u16 id)
504 return stream->ssn[id];
507 /* Return the next SSN number for this stream. */
508 static inline __u16 sctp_ssn_next(struct sctp_stream *stream, __u16 id)
510 return stream->ssn[id]++;
513 /* Skip over this ssn and all below. */
514 static inline void sctp_ssn_skip(struct sctp_stream *stream, __u16 id,
517 stream->ssn[id] = ssn+1;
521 * Pointers to address related SCTP functions.
522 * (i.e. things that depend on the address family.)
525 int (*sctp_xmit) (struct sk_buff *skb,
526 struct sctp_transport *,
528 int (*setsockopt) (struct sock *sk,
533 int (*getsockopt) (struct sock *sk,
538 int (*compat_setsockopt) (struct sock *sk,
543 int (*compat_getsockopt) (struct sock *sk,
548 struct dst_entry *(*get_dst) (struct sctp_association *asoc,
549 union sctp_addr *daddr,
550 union sctp_addr *saddr);
551 void (*get_saddr) (struct sctp_sock *sk,
552 struct sctp_association *asoc,
553 struct dst_entry *dst,
554 union sctp_addr *daddr,
555 union sctp_addr *saddr);
556 void (*copy_addrlist) (struct list_head *,
557 struct net_device *);
558 void (*dst_saddr) (union sctp_addr *saddr,
559 struct dst_entry *dst,
561 int (*cmp_addr) (const union sctp_addr *addr1,
562 const union sctp_addr *addr2);
563 void (*addr_copy) (union sctp_addr *dst,
564 union sctp_addr *src);
565 void (*from_skb) (union sctp_addr *,
568 void (*from_sk) (union sctp_addr *,
570 void (*to_sk_saddr) (union sctp_addr *,
572 void (*to_sk_daddr) (union sctp_addr *,
574 void (*from_addr_param) (union sctp_addr *,
575 union sctp_addr_param *,
576 __be16 port, int iif);
577 int (*to_addr_param) (const union sctp_addr *,
578 union sctp_addr_param *);
579 int (*addr_valid) (union sctp_addr *,
581 const struct sk_buff *);
582 sctp_scope_t (*scope) (union sctp_addr *);
583 void (*inaddr_any) (union sctp_addr *, __be16);
584 int (*is_any) (const union sctp_addr *);
585 int (*available) (union sctp_addr *,
587 int (*skb_iif) (const struct sk_buff *sk);
588 int (*is_ce) (const struct sk_buff *sk);
589 void (*seq_dump_addr)(struct seq_file *seq,
590 union sctp_addr *addr);
591 void (*ecn_capable)(struct sock *sk);
592 __u16 net_header_len;
594 sa_family_t sa_family;
595 struct list_head list;
598 struct sctp_af *sctp_get_af_specific(sa_family_t);
599 int sctp_register_af(struct sctp_af *);
601 /* Protocol family functions. */
603 void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
604 void (*skb_msgname) (struct sk_buff *, char *, int *);
605 int (*af_supported) (sa_family_t, struct sctp_sock *);
606 int (*cmp_addr) (const union sctp_addr *,
607 const union sctp_addr *,
609 int (*bind_verify) (struct sctp_sock *, union sctp_addr *);
610 int (*send_verify) (struct sctp_sock *, union sctp_addr *);
611 int (*supported_addrs)(const struct sctp_sock *, __be16 *);
612 struct sock *(*create_accept_sk) (struct sock *sk,
613 struct sctp_association *asoc);
614 void (*addr_v4map) (struct sctp_sock *, union sctp_addr *);
619 /* Structure to track chunk fragments that have been acked, but peer
620 * fragments of the same message have not.
622 struct sctp_datamsg {
623 /* Chunks waiting to be submitted to lower layer. */
624 struct list_head chunks;
625 /* Chunks that have been transmitted. */
626 struct list_head track;
627 /* Reference counting. */
629 /* When is this message no longer interesting to the peer? */
630 unsigned long expires_at;
631 /* Did the messenge fail to send? */
634 /* Control whether chunks from this message can be abandoned. */
638 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
639 struct sctp_sndrcvinfo *,
640 struct msghdr *, int len);
641 void sctp_datamsg_put(struct sctp_datamsg *);
642 void sctp_chunk_fail(struct sctp_chunk *, int error);
643 int sctp_chunk_abandoned(struct sctp_chunk *);
645 /* RFC2960 1.4 Key Terms
647 * o Chunk: A unit of information within an SCTP packet, consisting of
648 * a chunk header and chunk-specific content.
650 * As a matter of convenience, we remember the SCTP common header for
651 * each chunk as well as a few other header pointers...
654 struct list_head list;
658 /* This is our link to the per-transport transmitted list. */
659 struct list_head transmitted_list;
661 /* This field is used by chunks that hold fragmented data.
662 * For the first fragment this is the list that holds the rest of
663 * fragments. For the remaining fragments, this is the link to the
664 * frag_list maintained in the first fragment.
666 struct list_head frag_list;
668 /* This points to the sk_buff containing the actual data. */
671 /* These are the SCTP headers by reverse order in a packet.
672 * Note that some of these may happen more than once. In that
673 * case, we point at the "current" one, whatever that means
674 * for that level of header.
677 /* We point this at the FIRST TLV parameter to chunk_hdr. */
678 union sctp_params param_hdr;
681 struct sctp_datahdr *data_hdr;
682 struct sctp_inithdr *init_hdr;
683 struct sctp_sackhdr *sack_hdr;
684 struct sctp_heartbeathdr *hb_hdr;
685 struct sctp_sender_hb_info *hbs_hdr;
686 struct sctp_shutdownhdr *shutdown_hdr;
687 struct sctp_signed_cookie *cookie_hdr;
688 struct sctp_ecnehdr *ecne_hdr;
689 struct sctp_cwrhdr *ecn_cwr_hdr;
690 struct sctp_errhdr *err_hdr;
691 struct sctp_addiphdr *addip_hdr;
692 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
693 struct sctp_authhdr *auth_hdr;
698 struct sctp_chunkhdr *chunk_hdr;
699 struct sctphdr *sctp_hdr;
701 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
702 struct sctp_sndrcvinfo sinfo;
704 /* Which association does this belong to? */
705 struct sctp_association *asoc;
707 /* What endpoint received this chunk? */
708 struct sctp_ep_common *rcvr;
710 /* We fill this in if we are calculating RTT. */
711 unsigned long sent_at;
713 /* What is the origin IP address for this chunk? */
714 union sctp_addr source;
715 /* Destination address for this chunk. */
716 union sctp_addr dest;
718 /* For outbound message, track all fragments for SEND_FAILED. */
719 struct sctp_datamsg *msg;
721 /* For an inbound chunk, this tells us where it came from.
722 * For an outbound chunk, it tells us where we'd like it to
723 * go. It is NULL if we have no preference.
725 struct sctp_transport *transport;
727 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO
728 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
729 * spec violates the principle premis that all chunks are processed
732 struct sk_buff *auth_chunk;
734 __u8 rtt_in_progress; /* Is this chunk used for RTT calculation? */
735 __u8 resent; /* Has this chunk ever been retransmitted. */
736 __u8 has_tsn; /* Does this chunk have a TSN yet? */
737 __u8 has_ssn; /* Does this chunk have a SSN yet? */
738 __u8 singleton; /* Was this the only chunk in the packet? */
739 __u8 end_of_packet; /* Was this the last chunk in the packet? */
740 __u8 ecn_ce_done; /* Have we processed the ECN CE bit? */
741 __u8 pdiscard; /* Discard the whole packet now? */
742 __u8 tsn_gap_acked; /* Is this chunk acked by a GAP ACK? */
743 __s8 fast_retransmit; /* Is this chunk fast retransmitted? */
744 __u8 tsn_missing_report; /* Data chunk missing counter. */
745 __u8 data_accepted; /* At least 1 chunk in this packet accepted */
746 __u8 auth; /* IN: was auth'ed | OUT: needs auth */
747 __u8 has_asconf; /* IN: have seen an asconf before */
750 void sctp_chunk_hold(struct sctp_chunk *);
751 void sctp_chunk_put(struct sctp_chunk *);
752 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
754 void sctp_chunk_free(struct sctp_chunk *);
755 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
756 struct sctp_chunk *sctp_chunkify(struct sk_buff *,
757 const struct sctp_association *,
759 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
761 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
764 SCTP_ADDR_NEW, /* new address added to assoc/ep */
765 SCTP_ADDR_SRC, /* address can be used as source */
766 SCTP_ADDR_DEL, /* address about to be deleted */
769 /* This is a structure for holding either an IPv6 or an IPv4 address. */
770 struct sctp_sockaddr_entry {
771 struct list_head list;
778 typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *);
780 /* This structure holds lists of chunks as we are assembling for
784 /* These are the SCTP header values (host order) for the packet. */
786 __u16 destination_port;
789 /* This contains the payload chunks. */
790 struct list_head chunk_list;
792 /* This is the overhead of the sctp and ip headers. */
794 /* This is the total size of all chunks INCLUDING padding. */
797 /* The packet is destined for this transport address.
798 * The function we finally use to pass down to the next lower
799 * layer lives in the transport structure.
801 struct sctp_transport *transport;
803 /* pointer to the auth chunk for this packet */
804 struct sctp_chunk *auth;
806 /* This packet contains a COOKIE-ECHO chunk. */
807 __u8 has_cookie_echo;
809 /* This packet contains a SACK chunk. */
812 /* This packet contains an AUTH chunk */
815 /* This packet contains at least 1 DATA chunk */
818 /* SCTP cannot fragment this packet. So let ip fragment it. */
824 struct sctp_packet *sctp_packet_init(struct sctp_packet *,
825 struct sctp_transport *,
826 __u16 sport, __u16 dport);
827 struct sctp_packet *sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
828 sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *,
829 struct sctp_chunk *);
830 sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *,
831 struct sctp_chunk *);
832 int sctp_packet_transmit(struct sctp_packet *);
833 void sctp_packet_free(struct sctp_packet *);
835 static inline int sctp_packet_empty(struct sctp_packet *packet)
837 return (packet->size == packet->overhead);
840 /* This represents a remote transport address.
841 * For local transport addresses, we just use union sctp_addr.
843 * RFC2960 Section 1.4 Key Terms
845 * o Transport address: A Transport Address is traditionally defined
846 * by Network Layer address, Transport Layer protocol and Transport
847 * Layer port number. In the case of SCTP running over IP, a
848 * transport address is defined by the combination of an IP address
849 * and an SCTP port number (where SCTP is the Transport protocol).
851 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
853 * o The sender keeps a separate congestion control parameter set for
854 * each of the destination addresses it can send to (not each
855 * source-destination pair but for each destination). The parameters
856 * should decay if the address is not used for a long enough time
860 struct sctp_transport {
861 /* A list of transports. */
862 struct list_head transports;
864 /* Reference counting. */
868 /* This is the peer's IP address and port. */
869 union sctp_addr ipaddr;
871 /* These are the functions we call to handle LLP stuff. */
872 struct sctp_af *af_specific;
874 /* Which association do we belong to? */
875 struct sctp_association *asoc;
879 * 12.3 Per Transport Address Data
881 * For each destination transport address in the peer's
882 * address list derived from the INIT or INIT ACK chunk, a
883 * number of data elements needs to be maintained including:
885 /* RTO : The current retransmission timeout value. */
887 unsigned long last_rto;
889 __u32 rtt; /* This is the most recent RTT. */
891 /* RTTVAR : The current RTT variation. */
894 /* SRTT : The current smoothed round trip time. */
897 /* RTO-Pending : A flag used to track if one of the DATA
898 * chunks sent to this address is currently being
899 * used to compute a RTT. If this flag is 0,
900 * the next DATA chunk sent to this destination
901 * should be used to compute a RTT and this flag
902 * should be set. Every time the RTT
903 * calculation completes (i.e. the DATA chunk
904 * is SACK'd) clear this flag.
908 /* Flag to track the current fast recovery state */
912 * These are the congestion stats.
914 /* cwnd : The current congestion window. */
915 __u32 cwnd; /* This is the actual cwnd. */
917 /* ssthresh : The current slow start threshold value. */
920 /* partial : The tracking method for increase of cwnd when in
921 * bytes acked : congestion avoidance mode (see Section 6.2.2)
923 __u32 partial_bytes_acked;
925 /* Data that has been sent, but not acknowledged. */
928 /* TSN marking the fast recovery exit point */
929 __u32 fast_recovery_exit;
932 struct dst_entry *dst;
933 /* Source address. */
934 union sctp_addr saddr;
936 /* When was the last time(in jiffies) that a data packet was sent on
937 * this transport? This is used to adjust the cwnd when the transport
940 unsigned long last_time_used;
942 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
943 * the destination address every heartbeat interval.
945 unsigned long hbinterval;
947 /* SACK delay timeout */
948 unsigned long sackdelay;
950 /* When was the last time (in jiffies) that we heard from this
951 * transport? We use this to pick new active and retran paths.
953 unsigned long last_time_heard;
955 /* Last time(in jiffies) when cwnd is reduced due to the congestion
956 * indication based on ECNE chunk.
958 unsigned long last_time_ecne_reduced;
960 /* This is the max_retrans value for the transport and will
961 * be initialized from the assocs value. This can be changed
962 * using SCTP_SET_PEER_ADDR_PARAMS socket option.
966 /* is the Path MTU update pending on this tranport */
969 /* PMTU : The current known path MTU. */
972 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
975 /* The number of times INIT has been sent on this transport. */
978 /* state : The current state of this destination,
979 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKOWN.
983 /* These are the error stats for this destination. */
985 /* Error count : The current error count for this destination. */
986 unsigned short error_count;
988 /* Per : A timer used by each destination.
992 * [Everywhere else in the text this is called T3-rtx. -ed]
994 struct timer_list T3_rtx_timer;
996 /* Heartbeat timer is per destination. */
997 struct timer_list hb_timer;
999 /* Since we're using per-destination retransmission timers
1000 * (see above), we're also using per-destination "transmitted"
1001 * queues. This probably ought to be a private struct
1002 * accessible only within the outqueue, but it's not, yet.
1004 struct list_head transmitted;
1006 /* We build bundle-able packets for this transport here. */
1007 struct sctp_packet packet;
1009 /* This is the list of transports that have chunks to send. */
1010 struct list_head send_ready;
1012 int malloced; /* Is this structure kfree()able? */
1014 /* State information saved for SFR_CACC algorithm. The key
1015 * idea in SFR_CACC is to maintain state at the sender on a
1016 * per-destination basis when a changeover happens.
1017 * char changeover_active;
1018 * char cycling_changeover;
1019 * __u32 next_tsn_at_change;
1020 * char cacc_saw_newack;
1023 /* An unsigned integer, which stores the next TSN to be
1024 * used by the sender, at the moment of changeover.
1026 __u32 next_tsn_at_change;
1028 /* A flag which indicates the occurrence of a changeover */
1029 char changeover_active;
1031 /* A flag which indicates whether the change of primary is
1032 * the first switch to this destination address during an
1035 char cycling_changeover;
1037 /* A temporary flag, which is used during the processing of
1038 * a SACK to estimate the causative TSN(s)'s group.
1040 char cacc_saw_newack;
1043 /* 64-bit random number sent with heartbeat. */
1047 struct sctp_transport *sctp_transport_new(const union sctp_addr *,
1049 void sctp_transport_set_owner(struct sctp_transport *,
1050 struct sctp_association *);
1051 void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
1052 struct sctp_sock *);
1053 void sctp_transport_pmtu(struct sctp_transport *);
1054 void sctp_transport_free(struct sctp_transport *);
1055 void sctp_transport_reset_timers(struct sctp_transport *, int);
1056 void sctp_transport_hold(struct sctp_transport *);
1057 void sctp_transport_put(struct sctp_transport *);
1058 void sctp_transport_update_rto(struct sctp_transport *, __u32);
1059 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
1060 void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t);
1061 unsigned long sctp_transport_timeout(struct sctp_transport *);
1062 void sctp_transport_reset(struct sctp_transport *);
1063 void sctp_transport_update_pmtu(struct sctp_transport *, u32);
1066 /* This is the structure we use to queue packets as they come into
1067 * SCTP. We write packets to it and read chunks from it.
1070 /* This is actually a queue of sctp_chunk each
1071 * containing a partially decoded packet.
1073 struct list_head in_chunk_list;
1074 /* This is the packet which is currently off the in queue and is
1075 * being worked on through the inbound chunk processing.
1077 struct sctp_chunk *in_progress;
1079 /* This is the delayed task to finish delivering inbound
1082 struct work_struct immediate;
1084 int malloced; /* Is this structure kfree()able? */
1087 void sctp_inq_init(struct sctp_inq *);
1088 void sctp_inq_free(struct sctp_inq *);
1089 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
1090 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
1091 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *);
1092 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t);
1094 /* This is the structure we use to hold outbound chunks. You push
1095 * chunks in and they automatically pop out the other end as bundled
1096 * packets (it calls (*output_handler)()).
1098 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1099 * and 8.2 of the v13 draft.
1101 * It handles retransmissions. The connection to the timeout portion
1102 * of the state machine is through sctp_..._timeout() and timeout_handler.
1104 * If you feed it SACKs, it will eat them.
1106 * If you give it big chunks, it will fragment them.
1108 * It assigns TSN's to data chunks. This happens at the last possible
1109 * instant before transmission.
1111 * When free()'d, it empties itself out via output_handler().
1114 struct sctp_association *asoc;
1116 /* Data pending that has never been transmitted. */
1117 struct list_head out_chunk_list;
1119 unsigned out_qlen; /* Total length of queued data chunks. */
1121 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1124 /* These are control chunks we want to send. */
1125 struct list_head control_chunk_list;
1127 /* These are chunks that have been sacked but are above the
1128 * CTSN, or cumulative tsn ack point.
1130 struct list_head sacked;
1132 /* Put chunks on this list to schedule them for
1135 struct list_head retransmit;
1137 /* Put chunks on this list to save them for FWD TSN processing as
1138 * they were abandoned.
1140 struct list_head abandoned;
1142 /* How many unackd bytes do we have in-flight? */
1143 __u32 outstanding_bytes;
1145 /* Are we doing fast-rtx on this queue */
1151 /* Is this structure empty? */
1154 /* Are we kfree()able? */
1158 void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1159 void sctp_outq_teardown(struct sctp_outq *);
1160 void sctp_outq_free(struct sctp_outq*);
1161 int sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk);
1162 int sctp_outq_flush(struct sctp_outq *, int);
1163 int sctp_outq_sack(struct sctp_outq *, struct sctp_sackhdr *);
1164 int sctp_outq_is_empty(const struct sctp_outq *);
1165 void sctp_outq_restart(struct sctp_outq *);
1167 void sctp_retransmit(struct sctp_outq *, struct sctp_transport *,
1168 sctp_retransmit_reason_t);
1169 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1170 int sctp_outq_uncork(struct sctp_outq *);
1171 /* Uncork and flush an outqueue. */
1172 static inline void sctp_outq_cork(struct sctp_outq *q)
1177 /* These bind address data fields common between endpoints and associations */
1178 struct sctp_bind_addr {
1180 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1182 * SCTP Port: The local SCTP port number the endpoint is
1187 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1189 * Address List: The list of IP addresses that this instance
1190 * has bound. This information is passed to one's
1191 * peer(s) in INIT and INIT ACK chunks.
1193 struct list_head address_list;
1195 int malloced; /* Are we kfree()able? */
1198 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1199 void sctp_bind_addr_free(struct sctp_bind_addr *);
1200 int sctp_bind_addr_copy(struct sctp_bind_addr *dest,
1201 const struct sctp_bind_addr *src,
1202 sctp_scope_t scope, gfp_t gfp,
1204 int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
1205 const struct sctp_bind_addr *src,
1207 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1208 __u8 addr_state, gfp_t gfp);
1209 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1210 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1211 struct sctp_sock *);
1212 int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
1213 const union sctp_addr *addr);
1214 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp,
1215 const union sctp_addr *addrs,
1217 struct sctp_sock *opt);
1218 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1221 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1222 __u16 port, gfp_t gfp);
1224 sctp_scope_t sctp_scope(const union sctp_addr *);
1225 int sctp_in_scope(const union sctp_addr *addr, const sctp_scope_t scope);
1226 int sctp_is_any(const union sctp_addr *addr);
1227 int sctp_addr_is_valid(const union sctp_addr *addr);
1230 /* What type of endpoint? */
1232 SCTP_EP_TYPE_SOCKET,
1233 SCTP_EP_TYPE_ASSOCIATION,
1234 } sctp_endpoint_type_t;
1237 * A common base class to bridge the implmentation view of a
1238 * socket (usually listening) endpoint versus an association's
1240 * This common structure is useful for several purposes:
1241 * 1) Common interface for lookup routines.
1242 * a) Subfunctions work for either endpoint or association
1243 * b) Single interface to lookup allows hiding the lookup lock rather
1244 * than acquiring it externally.
1245 * 2) Common interface for the inbound chunk handling/state machine.
1246 * 3) Common object handling routines for reference counting, etc.
1247 * 4) Disentangle association lookup from endpoint lookup, where we
1248 * do not have to find our endpoint to find our association.
1252 struct sctp_ep_common {
1253 /* Fields to help us manage our entries in the hash tables. */
1254 struct hlist_node node;
1257 /* Runtime type information. What kind of endpoint is this? */
1258 sctp_endpoint_type_t type;
1260 /* Some fields to help us manage this object.
1261 * refcnt - Reference count access to this object.
1262 * dead - Do not attempt to use this object.
1263 * malloced - Do we need to kfree this object?
1269 /* What socket does this endpoint belong to? */
1272 /* This is where we receive inbound chunks. */
1273 struct sctp_inq inqueue;
1275 /* This substructure includes the defining parameters of the
1277 * bind_addr.port is our shared port number.
1278 * bind_addr.address_list is our set of local IP addresses.
1280 struct sctp_bind_addr bind_addr;
1284 /* RFC Section 1.4 Key Terms
1286 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1287 * multi-homed host, an SCTP endpoint is represented to its peers as a
1288 * combination of a set of eligible destination transport addresses to
1289 * which SCTP packets can be sent and a set of eligible source
1290 * transport addresses from which SCTP packets can be received.
1291 * All transport addresses used by an SCTP endpoint must use the
1292 * same port number, but can use multiple IP addresses. A transport
1293 * address used by an SCTP endpoint must not be used by another
1294 * SCTP endpoint. In other words, a transport address is unique
1295 * to an SCTP endpoint.
1297 * From an implementation perspective, each socket has one of these.
1298 * A TCP-style socket will have exactly one association on one of
1299 * these. An UDP-style socket will have multiple associations hanging
1303 struct sctp_endpoint {
1304 /* Common substructure for endpoint and association. */
1305 struct sctp_ep_common base;
1307 /* Associations: A list of current associations and mappings
1308 * to the data consumers for each association. This
1309 * may be in the form of a hash table or other
1310 * implementation dependent structure. The data
1311 * consumers may be process identification
1312 * information such as file descriptors, named pipe
1313 * pointer, or table pointers dependent on how SCTP
1316 /* This is really a list of struct sctp_association entries. */
1317 struct list_head asocs;
1319 /* Secret Key: A secret key used by this endpoint to compute
1320 * the MAC. This SHOULD be a cryptographic quality
1321 * random number with a sufficient length.
1322 * Discussion in [RFC1750] can be helpful in
1323 * selection of the key.
1325 __u8 secret_key[SCTP_HOW_MANY_SECRETS][SCTP_SECRET_SIZE];
1330 /* digest: This is a digest of the sctp cookie. This field is
1331 * only used on the receive path when we try to validate
1332 * that the cookie has not been tampered with. We put
1333 * this here so we pre-allocate this once and can re-use
1338 /* sendbuf acct. policy. */
1339 __u32 sndbuf_policy;
1341 /* rcvbuf acct. policy. */
1342 __u32 rcvbuf_policy;
1344 /* SCTP AUTH: array of the HMACs that will be allocated
1345 * we need this per association so that we don't serialize
1347 struct crypto_hash **auth_hmacs;
1349 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1350 struct sctp_hmac_algo_param *auth_hmacs_list;
1352 /* SCTP-AUTH: chunks to authenticate encoded into parameter */
1353 struct sctp_chunks_param *auth_chunk_list;
1355 /* SCTP-AUTH: endpoint shared keys */
1356 struct list_head endpoint_shared_keys;
1357 __u16 active_key_id;
1360 /* Recover the outter endpoint structure. */
1361 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1363 struct sctp_endpoint *ep;
1365 ep = container_of(base, struct sctp_endpoint, base);
1369 /* These are function signatures for manipulating endpoints. */
1370 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1371 void sctp_endpoint_free(struct sctp_endpoint *);
1372 void sctp_endpoint_put(struct sctp_endpoint *);
1373 void sctp_endpoint_hold(struct sctp_endpoint *);
1374 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1375 struct sctp_association *sctp_endpoint_lookup_assoc(
1376 const struct sctp_endpoint *ep,
1377 const union sctp_addr *paddr,
1378 struct sctp_transport **);
1379 int sctp_endpoint_is_peeled_off(struct sctp_endpoint *,
1380 const union sctp_addr *);
1381 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1382 const union sctp_addr *);
1383 int sctp_has_association(const union sctp_addr *laddr,
1384 const union sctp_addr *paddr);
1386 int sctp_verify_init(const struct sctp_association *asoc, sctp_cid_t,
1387 sctp_init_chunk_t *peer_init, struct sctp_chunk *chunk,
1388 struct sctp_chunk **err_chunk);
1389 int sctp_process_init(struct sctp_association *, sctp_cid_t cid,
1390 const union sctp_addr *peer,
1391 sctp_init_chunk_t *init, gfp_t gfp);
1392 __u32 sctp_generate_tag(const struct sctp_endpoint *);
1393 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
1395 struct sctp_inithdr_host {
1398 __u16 num_outbound_streams;
1399 __u16 num_inbound_streams;
1405 * 12. Recommended Transmission Control Block (TCB) Parameters
1407 * This section details a recommended set of parameters that should
1408 * be contained within the TCB for an implementation. This section is
1409 * for illustrative purposes and should not be deemed as requirements
1410 * on an implementation or as an exhaustive list of all parameters
1411 * inside an SCTP TCB. Each implementation may need its own additional
1412 * parameters for optimization.
1416 /* Here we have information about each individual association. */
1417 struct sctp_association {
1419 /* A base structure common to endpoint and association.
1420 * In this context, it represents the associations's view
1421 * of the local endpoint of the association.
1423 struct sctp_ep_common base;
1425 /* Associations on the same socket. */
1426 struct list_head asocs;
1428 /* association id. */
1429 sctp_assoc_t assoc_id;
1431 /* This is our parent endpoint. */
1432 struct sctp_endpoint *ep;
1434 /* These are those association elements needed in the cookie. */
1435 struct sctp_cookie c;
1437 /* This is all information about our peer. */
1441 * Peer Rwnd : Current calculated value of the peer's rwnd.
1445 /* transport_addr_list
1447 * Peer : A list of SCTP transport addresses that the
1448 * Transport : peer is bound to. This information is derived
1449 * Address : from the INIT or INIT ACK and is used to
1450 * List : associate an inbound packet with a given
1451 * : association. Normally this information is
1452 * : hashed or keyed for quick lookup and access
1454 * : The list is also initialized with the list
1455 * : of addresses passed with the sctp_connectx()
1458 * It is a list of SCTP_transport's.
1460 struct list_head transport_addr_list;
1464 * Peer : A count of the number of peer addresses
1465 * Transport : in the Peer Transport Address List.
1469 __u16 transport_count;
1472 * The transport layer port number.
1478 * Primary : This is the current primary destination
1479 * Path : transport address of the peer endpoint. It
1480 * : may also specify a source transport address
1481 * : on this endpoint.
1483 * All of these paths live on transport_addr_list.
1485 * At the bakeoffs, we discovered that the intent of
1486 * primaryPath is that it only changes when the ULP
1487 * asks to have it changed. We add the activePath to
1488 * designate the connection we are currently using to
1489 * transmit new data and most control chunks.
1491 struct sctp_transport *primary_path;
1493 /* Cache the primary path address here, when we
1494 * need a an address for msg_name.
1496 union sctp_addr primary_addr;
1499 * The path that we are currently using to
1500 * transmit new data and most control chunks.
1502 struct sctp_transport *active_path;
1506 * RFC2960 6.4 Multi-homed SCTP Endpoints
1508 * Furthermore, when its peer is multi-homed, an
1509 * endpoint SHOULD try to retransmit a chunk to an
1510 * active destination transport address that is
1511 * different from the last destination address to
1512 * which the DATA chunk was sent.
1514 struct sctp_transport *retran_path;
1516 /* Pointer to last transport I have sent on. */
1517 struct sctp_transport *last_sent_to;
1519 /* This is the last transport I have received DATA on. */
1520 struct sctp_transport *last_data_from;
1523 * Mapping An array of bits or bytes indicating which out of
1524 * Array order TSN's have been received (relative to the
1525 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1526 * order packets have been received, this array
1527 * will be set to all zero. This structure may be
1528 * in the form of a circular buffer or bit array.
1530 * Last Rcvd : This is the last TSN received in
1531 * TSN : sequence. This value is set initially by
1532 * : taking the peer's Initial TSN, received in
1533 * : the INIT or INIT ACK chunk, and subtracting
1536 * Throughout most of the specification this is called the
1537 * "Cumulative TSN ACK Point". In this case, we
1538 * ignore the advice in 12.2 in favour of the term
1539 * used in the bulk of the text. This value is hidden
1540 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1542 struct sctp_tsnmap tsn_map;
1543 __u8 _map[sctp_tsnmap_storage_size(SCTP_TSN_MAP_SIZE)];
1545 /* Ack State : This flag indicates if the next received
1546 * : packet is to be responded to with a
1547 * : SACK. This is initializedto 0. When a packet
1548 * : is received it is incremented. If this value
1549 * : reaches 2 or more, a SACK is sent and the
1550 * : value is reset to 0. Note: This is used only
1551 * : when no DATA chunks are received out of
1552 * : order. When DATA chunks are out of order,
1553 * : SACK's are not delayed (see Section 6).
1555 __u8 sack_needed; /* Do we need to sack the peer? */
1557 /* These are capabilities which our peer advertised. */
1558 __u8 ecn_capable; /* Can peer do ECN? */
1559 __u8 ipv4_address; /* Peer understands IPv4 addresses? */
1560 __u8 ipv6_address; /* Peer understands IPv6 addresses? */
1561 __u8 hostname_address;/* Peer understands DNS addresses? */
1562 __u8 asconf_capable; /* Does peer support ADDIP? */
1563 __u8 prsctp_capable; /* Can peer do PR-SCTP? */
1564 __u8 auth_capable; /* Is peer doing SCTP-AUTH? */
1566 __u32 adaptation_ind; /* Adaptation Code point. */
1568 /* This mask is used to disable sending the ASCONF chunk
1569 * with specified parameter to peer.
1571 __be16 addip_disabled_mask;
1573 struct sctp_inithdr_host i;
1577 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1578 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1579 * Initial TSN Value minus 1
1583 /* SCTP-AUTH: We need to know pears random number, hmac list
1584 * and authenticated chunk list. All that is part of the
1585 * cookie and these are just pointers to those locations
1587 sctp_random_param_t *peer_random;
1588 sctp_chunks_param_t *peer_chunks;
1589 sctp_hmac_algo_param_t *peer_hmacs;
1592 /* State : A state variable indicating what state the
1593 * : association is in, i.e. COOKIE-WAIT,
1594 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1595 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1597 * Note: No "CLOSED" state is illustrated since if a
1598 * association is "CLOSED" its TCB SHOULD be removed.
1600 * In this implementation we DO have a CLOSED
1601 * state which is used during initiation and shutdown.
1603 * State takes values from SCTP_STATE_*.
1607 /* The cookie life I award for any cookie. */
1608 struct timeval cookie_life;
1610 /* Overall : The overall association error count.
1611 * Error Count : [Clear this any time I get something.]
1613 int overall_error_count;
1615 /* These are the association's initial, max, and min RTO values.
1616 * These values will be initialized by system defaults, but can
1617 * be modified via the SCTP_RTOINFO socket option.
1619 unsigned long rto_initial;
1620 unsigned long rto_max;
1621 unsigned long rto_min;
1623 /* Maximum number of new data packets that can be sent in a burst. */
1626 /* This is the max_retrans value for the association. This value will
1627 * be initialized initialized from system defaults, but can be
1628 * modified by the SCTP_ASSOCINFO socket option.
1632 /* Maximum number of times the endpoint will retransmit INIT */
1633 __u16 max_init_attempts;
1635 /* How many times have we resent an INIT? */
1638 /* The largest timeout or RTO value to use in attempting an INIT */
1639 unsigned long max_init_timeo;
1641 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1642 * the destination address every heartbeat interval. This value
1643 * will be inherited by all new transports.
1645 unsigned long hbinterval;
1647 /* This is the max_retrans value for new transports in the
1652 /* Flag that path mtu update is pending */
1655 /* Association : The smallest PMTU discovered for all of the
1656 * PMTU : peer's transport addresses.
1660 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1663 /* SACK delay timeout */
1664 unsigned long sackdelay;
1667 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES];
1668 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1670 /* Transport to which SHUTDOWN chunk was last sent. */
1671 struct sctp_transport *shutdown_last_sent_to;
1673 /* How many times have we resent a SHUTDOWN */
1674 int shutdown_retries;
1676 /* Transport to which INIT chunk was last sent. */
1677 struct sctp_transport *init_last_sent_to;
1679 /* Next TSN : The next TSN number to be assigned to a new
1680 * : DATA chunk. This is sent in the INIT or INIT
1681 * : ACK chunk to the peer and incremented each
1682 * : time a DATA chunk is assigned a TSN
1683 * : (normally just prior to transmit or during
1689 * Last Rcvd : This is the last TSN received in sequence. This value
1690 * TSN : is set initially by taking the peer's Initial TSN,
1691 * : received in the INIT or INIT ACK chunk, and
1692 * : subtracting one from it.
1694 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1697 __u32 ctsn_ack_point;
1699 /* PR-SCTP Advanced.Peer.Ack.Point */
1700 __u32 adv_peer_ack_point;
1702 /* Highest TSN that is acknowledged by incoming SACKs. */
1703 __u32 highest_sacked;
1705 /* The number of unacknowledged data chunks. Reported through
1706 * the SCTP_STATUS sockopt.
1710 /* The total number of data chunks that we've had to retransmit
1711 * as the result of a T3 timer expiration
1713 __u32 rtx_data_chunks;
1715 /* This is the association's receive buffer space. This value is used
1716 * to set a_rwnd field in an INIT or a SACK chunk.
1720 /* This is the last advertised value of rwnd over a SACK chunk. */
1723 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1724 * to slop over a maximum of the association's frag_point.
1728 /* This is the sndbuf size in use for the association.
1729 * This corresponds to the sndbuf size for the association,
1730 * as specified in the sk->sndbuf.
1734 /* This is the amount of memory that this association has allocated
1735 * in the receive path at any given time.
1737 atomic_t rmem_alloc;
1739 /* This is the wait queue head for send requests waiting on
1740 * the association sndbuf space.
1742 wait_queue_head_t wait;
1744 /* The message size at which SCTP fragmentation will occur. */
1747 /* Counter used to count INIT errors. */
1748 int init_err_counter;
1750 /* Count the number of INIT cycles (for doubling timeout). */
1753 /* Default send parameters. */
1754 __u16 default_stream;
1755 __u16 default_flags;
1757 __u32 default_context;
1758 __u32 default_timetolive;
1760 /* Default receive parameters */
1761 __u32 default_rcv_context;
1763 /* This tracks outbound ssn for a given stream. */
1764 struct sctp_ssnmap *ssnmap;
1766 /* All outbound chunks go through this structure. */
1767 struct sctp_outq outqueue;
1769 /* A smart pipe that will handle reordering and fragmentation,
1770 * as well as handle passing events up to the ULP.
1772 struct sctp_ulpq ulpq;
1774 /* Last TSN that caused an ECNE Chunk to be sent. */
1775 __u32 last_ecne_tsn;
1777 /* Last TSN that caused a CWR Chunk to be sent. */
1780 /* How many duplicated TSNs have we seen? */
1783 /* Number of seconds of idle time before an association is closed.
1784 * In the association context, this is really used as a boolean
1785 * since the real timeout is stored in the timeouts array
1789 /* These are to support
1790 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1791 * and Enforcement of Flow and Message Limits"
1792 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1793 * or "ADDIP" for short.
1798 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1800 * R1) One and only one ASCONF Chunk MAY be in transit and
1801 * unacknowledged at any one time. If a sender, after sending
1802 * an ASCONF chunk, decides it needs to transfer another
1803 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1804 * returns from the previous ASCONF Chunk before sending a
1805 * subsequent ASCONF. Note this restriction binds each side,
1806 * so at any time two ASCONF may be in-transit on any given
1807 * association (one sent from each endpoint).
1809 * [This is our one-and-only-one ASCONF in flight. If we do
1810 * not have an ASCONF in flight, this is NULL.]
1812 struct sctp_chunk *addip_last_asconf;
1814 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
1816 * This is needed to implement itmes E1 - E4 of the updated
1817 * spec. Here is the justification:
1819 * Since the peer may bundle multiple ASCONF chunks toward us,
1820 * we now need the ability to cache multiple ACKs. The section
1821 * describes in detail how they are cached and cleaned up.
1823 struct list_head asconf_ack_list;
1825 /* These ASCONF chunks are waiting to be sent.
1827 * These chunaks can't be pushed to outqueue until receiving
1828 * ASCONF_ACK for the previous ASCONF indicated by
1829 * addip_last_asconf, so as to guarantee that only one ASCONF
1830 * is in flight at any time.
1832 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1834 * In defining the ASCONF Chunk transfer procedures, it is
1835 * essential that these transfers MUST NOT cause congestion
1836 * within the network. To achieve this, we place these
1837 * restrictions on the transfer of ASCONF Chunks:
1839 * R1) One and only one ASCONF Chunk MAY be in transit and
1840 * unacknowledged at any one time. If a sender, after sending
1841 * an ASCONF chunk, decides it needs to transfer another
1842 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1843 * returns from the previous ASCONF Chunk before sending a
1844 * subsequent ASCONF. Note this restriction binds each side,
1845 * so at any time two ASCONF may be in-transit on any given
1846 * association (one sent from each endpoint).
1849 * [I really think this is EXACTLY the sort of intelligence
1850 * which already resides in sctp_outq. Please move this
1851 * queue and its supporting logic down there. --piggy]
1853 struct list_head addip_chunk_list;
1855 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1857 * A2) A serial number should be assigned to the Chunk. The
1858 * serial number SHOULD be a monotonically increasing
1859 * number. The serial number SHOULD be initialized at
1860 * the start of the association to the same value as the
1861 * Initial TSN and every time a new ASCONF chunk is created
1862 * it is incremented by one after assigning the serial number
1863 * to the newly created chunk.
1866 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
1868 * Serial Number : 32 bits (unsigned integer)
1870 * This value represents a Serial Number for the ASCONF
1871 * Chunk. The valid range of Serial Number is from 0 to
1872 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
1873 * after reaching 4294967295.
1877 /* SCTP AUTH: list of the endpoint shared keys. These
1878 * keys are provided out of band by the user applicaton
1879 * and can't change during the lifetime of the association
1881 struct list_head endpoint_shared_keys;
1884 * The current generated assocaition shared key (secret)
1886 struct sctp_auth_bytes *asoc_shared_key;
1888 /* SCTP AUTH: hmac id of the first peer requested algorithm
1891 __u16 default_hmac_id;
1893 __u16 active_key_id;
1895 /* Need to send an ECNE Chunk? */
1898 /* Is it a temporary association? */
1903 /* An eyecatcher for determining if we are really looking at an
1904 * association data structure.
1907 SCTP_ASSOC_EYECATCHER = 0xa550c123,
1910 /* Recover the outter association structure. */
1911 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
1913 struct sctp_association *asoc;
1915 asoc = container_of(base, struct sctp_association, base);
1919 /* These are function signatures for manipulating associations. */
1922 struct sctp_association *
1923 sctp_association_new(const struct sctp_endpoint *, const struct sock *,
1924 sctp_scope_t scope, gfp_t gfp);
1925 void sctp_association_free(struct sctp_association *);
1926 void sctp_association_put(struct sctp_association *);
1927 void sctp_association_hold(struct sctp_association *);
1929 struct sctp_transport *sctp_assoc_choose_init_transport(
1930 struct sctp_association *);
1931 struct sctp_transport *sctp_assoc_choose_shutdown_transport(
1932 struct sctp_association *);
1933 void sctp_assoc_update_retran_path(struct sctp_association *);
1934 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
1935 const union sctp_addr *);
1936 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1937 const union sctp_addr *laddr);
1938 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
1939 const union sctp_addr *address,
1941 const int peer_state);
1942 void sctp_assoc_del_peer(struct sctp_association *asoc,
1943 const union sctp_addr *addr);
1944 void sctp_assoc_rm_peer(struct sctp_association *asoc,
1945 struct sctp_transport *peer);
1946 void sctp_assoc_control_transport(struct sctp_association *,
1947 struct sctp_transport *,
1948 sctp_transport_cmd_t, sctp_sn_error_t);
1949 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
1950 struct sctp_transport *sctp_assoc_is_match(struct sctp_association *,
1951 const union sctp_addr *,
1952 const union sctp_addr *);
1953 void sctp_assoc_migrate(struct sctp_association *, struct sock *);
1954 void sctp_assoc_update(struct sctp_association *old,
1955 struct sctp_association *new);
1957 __u32 sctp_association_get_next_tsn(struct sctp_association *);
1959 void sctp_assoc_sync_pmtu(struct sctp_association *);
1960 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned);
1961 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned);
1962 void sctp_assoc_set_primary(struct sctp_association *,
1963 struct sctp_transport *);
1964 void sctp_assoc_del_nonprimary_peers(struct sctp_association *,
1965 struct sctp_transport *);
1966 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *,
1968 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
1969 struct sctp_cookie*,
1971 int sctp_assoc_set_id(struct sctp_association *, gfp_t);
1972 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc);
1973 struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
1974 const struct sctp_association *asoc,
1978 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1979 const union sctp_addr *ss2);
1980 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
1982 /* A convenience structure to parse out SCTP specific CMSGs. */
1983 typedef struct sctp_cmsgs {
1984 struct sctp_initmsg *init;
1985 struct sctp_sndrcvinfo *info;
1988 /* Structure for tracking memory objects */
1992 } sctp_dbg_objcnt_entry_t;
1994 #endif /* __sctp_structs_h__ */