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;
278 __u32 default_rcv_context;
280 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
281 * the destination address every heartbeat interval. This value
282 * will be inherited by all new associations.
286 /* This is the max_retrans value for new associations. */
289 /* The initial Path MTU to use for new associations. */
292 /* The default SACK delay timeout for new associations. */
295 /* Flags controling Heartbeat, SACK delay, and Path MTU Discovery. */
298 struct sctp_initmsg initmsg;
299 struct sctp_rtoinfo rtoinfo;
300 struct sctp_paddrparams paddrparam;
301 struct sctp_event_subscribe subscribe;
302 struct sctp_assocparams assocparams;
306 __u8 disable_fragments;
308 __u8 frag_interleave;
309 __u32 adaptation_ind;
313 /* Receive to here while partial delivery is in effect. */
314 struct sk_buff_head pd_lobby;
317 static inline struct sctp_sock *sctp_sk(const struct sock *sk)
319 return (struct sctp_sock *)sk;
322 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
324 return (struct sock *)sp;
327 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
329 struct sctp_sock sctp;
330 struct ipv6_pinfo inet6;
332 #endif /* CONFIG_IPV6 */
335 /* This is our APPLICATION-SPECIFIC state cookie.
336 * THIS IS NOT DICTATED BY THE SPECIFICATION.
338 /* These are the parts of an association which we send in the cookie.
339 * Most of these are straight out of:
340 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
346 /* My : Tag expected in every inbound packet and sent
347 * Verification: in the INIT or INIT ACK chunk.
352 /* Peer's : Tag expected in every outbound packet except
353 * Verification: in the INIT chunk.
358 /* The rest of these are not from the spec, but really need to
362 /* My Tie Tag : Assist in discovering a restarting association. */
365 /* Peer's Tie Tag: Assist in discovering a restarting association. */
368 /* When does this cookie expire? */
369 struct timeval expiration;
371 /* Number of inbound/outbound streams which are set
372 * and negotiated during the INIT process.
374 __u16 sinit_num_ostreams;
375 __u16 sinit_max_instreams;
377 /* This is the first sequence number I used. */
380 /* This holds the originating address of the INIT packet. */
381 union sctp_addr peer_addr;
384 * Include the source port of the INIT-ACK
390 /* Padding for future use */
393 __u32 adaptation_ind;
396 /* This is a shim for my peer's INIT packet, followed by
397 * a copy of the raw address list of the association.
398 * The length of the raw address list is saved in the
399 * raw_addr_list_len field, which will be used at the time when
400 * the association TCB is re-constructed from the cookie.
402 __u32 raw_addr_list_len;
403 struct sctp_init_chunk peer_init[0];
407 /* The format of our cookie that we send to our peer. */
408 struct sctp_signed_cookie {
409 __u8 signature[SCTP_SECRET_SIZE];
410 __u32 __pad; /* force sctp_cookie alignment to 64 bits */
411 struct sctp_cookie c;
412 } __attribute__((packed));
414 /* This is another convenience type to allocate memory for address
415 * params for the maximum size and pass such structures around
418 union sctp_addr_param {
419 struct sctp_ipv4addr_param v4;
420 struct sctp_ipv6addr_param v6;
423 /* A convenience type to allow walking through the various
424 * parameters and avoid casting all over the place.
428 struct sctp_paramhdr *p;
429 struct sctp_cookie_preserve_param *life;
430 struct sctp_hostname_param *dns;
431 struct sctp_cookie_param *cookie;
432 struct sctp_supported_addrs_param *sat;
433 struct sctp_ipv4addr_param *v4;
434 struct sctp_ipv6addr_param *v6;
435 union sctp_addr_param *addr;
436 struct sctp_adaptation_ind_param *aind;
439 /* RFC 2960. Section 3.3.5 Heartbeat.
440 * Heartbeat Information: variable length
441 * The Sender-specific Heartbeat Info field should normally include
442 * information about the sender's current time when this HEARTBEAT
443 * chunk is sent and the destination transport address to which this
444 * HEARTBEAT is sent (see Section 8.3).
446 typedef struct sctp_sender_hb_info {
447 struct sctp_paramhdr param_hdr;
448 union sctp_addr daddr;
449 unsigned long sent_at;
451 } __attribute__((packed)) sctp_sender_hb_info_t;
454 * RFC 2960 1.3.2 Sequenced Delivery within Streams
456 * The term "stream" is used in SCTP to refer to a sequence of user
457 * messages that are to be delivered to the upper-layer protocol in
458 * order with respect to other messages within the same stream. This is
459 * in contrast to its usage in TCP, where it refers to a sequence of
460 * bytes (in this document a byte is assumed to be eight bits).
463 * This is the structure we use to track both our outbound and inbound
464 * SSN, or Stream Sequence Numbers.
473 struct sctp_stream in;
474 struct sctp_stream out;
478 struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out,
480 void sctp_ssnmap_free(struct sctp_ssnmap *map);
481 void sctp_ssnmap_clear(struct sctp_ssnmap *map);
483 /* What is the current SSN number for this stream? */
484 static inline __u16 sctp_ssn_peek(struct sctp_stream *stream, __u16 id)
486 return stream->ssn[id];
489 /* Return the next SSN number for this stream. */
490 static inline __u16 sctp_ssn_next(struct sctp_stream *stream, __u16 id)
492 return stream->ssn[id]++;
495 /* Skip over this ssn and all below. */
496 static inline void sctp_ssn_skip(struct sctp_stream *stream, __u16 id,
499 stream->ssn[id] = ssn+1;
503 * Pointers to address related SCTP functions.
504 * (i.e. things that depend on the address family.)
507 int (*sctp_xmit) (struct sk_buff *skb,
508 struct sctp_transport *,
510 int (*setsockopt) (struct sock *sk,
515 int (*getsockopt) (struct sock *sk,
520 int (*compat_setsockopt) (struct sock *sk,
525 int (*compat_getsockopt) (struct sock *sk,
530 struct dst_entry *(*get_dst) (struct sctp_association *asoc,
531 union sctp_addr *daddr,
532 union sctp_addr *saddr);
533 void (*get_saddr) (struct sctp_association *asoc,
534 struct dst_entry *dst,
535 union sctp_addr *daddr,
536 union sctp_addr *saddr);
537 void (*copy_addrlist) (struct list_head *,
538 struct net_device *);
539 void (*dst_saddr) (union sctp_addr *saddr,
540 struct dst_entry *dst,
542 int (*cmp_addr) (const union sctp_addr *addr1,
543 const union sctp_addr *addr2);
544 void (*addr_copy) (union sctp_addr *dst,
545 union sctp_addr *src);
546 void (*from_skb) (union sctp_addr *,
549 void (*from_sk) (union sctp_addr *,
551 void (*to_sk_saddr) (union sctp_addr *,
553 void (*to_sk_daddr) (union sctp_addr *,
555 void (*from_addr_param) (union sctp_addr *,
556 union sctp_addr_param *,
557 __be16 port, int iif);
558 int (*to_addr_param) (const union sctp_addr *,
559 union sctp_addr_param *);
560 int (*addr_valid) (union sctp_addr *,
562 const struct sk_buff *);
563 sctp_scope_t (*scope) (union sctp_addr *);
564 void (*inaddr_any) (union sctp_addr *, __be16);
565 int (*is_any) (const union sctp_addr *);
566 int (*available) (union sctp_addr *,
568 int (*skb_iif) (const struct sk_buff *sk);
569 int (*is_ce) (const struct sk_buff *sk);
570 void (*seq_dump_addr)(struct seq_file *seq,
571 union sctp_addr *addr);
572 __u16 net_header_len;
574 sa_family_t sa_family;
575 struct list_head list;
578 struct sctp_af *sctp_get_af_specific(sa_family_t);
579 int sctp_register_af(struct sctp_af *);
581 /* Protocol family functions. */
583 void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
584 void (*skb_msgname) (struct sk_buff *, char *, int *);
585 int (*af_supported) (sa_family_t, struct sctp_sock *);
586 int (*cmp_addr) (const union sctp_addr *,
587 const union sctp_addr *,
589 int (*bind_verify) (struct sctp_sock *, union sctp_addr *);
590 int (*send_verify) (struct sctp_sock *, union sctp_addr *);
591 int (*supported_addrs)(const struct sctp_sock *, __be16 *);
592 struct sock *(*create_accept_sk) (struct sock *sk,
593 struct sctp_association *asoc);
594 void (*addr_v4map) (struct sctp_sock *, union sctp_addr *);
599 /* Structure to track chunk fragments that have been acked, but peer
600 * fragments of the same message have not.
602 struct sctp_datamsg {
603 /* Chunks waiting to be submitted to lower layer. */
604 struct list_head chunks;
605 /* Chunks that have been transmitted. */
606 struct list_head track;
607 /* Reference counting. */
609 /* When is this message no longer interesting to the peer? */
610 unsigned long expires_at;
611 /* Did the messenge fail to send? */
614 /* Control whether chunks from this message can be abandoned. */
618 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
619 struct sctp_sndrcvinfo *,
620 struct msghdr *, int len);
621 void sctp_datamsg_put(struct sctp_datamsg *);
622 void sctp_datamsg_free(struct sctp_datamsg *);
623 void sctp_datamsg_track(struct sctp_chunk *);
624 void sctp_chunk_fail(struct sctp_chunk *, int error);
625 int sctp_chunk_abandoned(struct sctp_chunk *);
627 /* RFC2960 1.4 Key Terms
629 * o Chunk: A unit of information within an SCTP packet, consisting of
630 * a chunk header and chunk-specific content.
632 * As a matter of convenience, we remember the SCTP common header for
633 * each chunk as well as a few other header pointers...
636 struct list_head list;
640 /* This is our link to the per-transport transmitted list. */
641 struct list_head transmitted_list;
643 /* This field is used by chunks that hold fragmented data.
644 * For the first fragment this is the list that holds the rest of
645 * fragments. For the remaining fragments, this is the link to the
646 * frag_list maintained in the first fragment.
648 struct list_head frag_list;
650 /* This points to the sk_buff containing the actual data. */
653 /* These are the SCTP headers by reverse order in a packet.
654 * Note that some of these may happen more than once. In that
655 * case, we point at the "current" one, whatever that means
656 * for that level of header.
659 /* We point this at the FIRST TLV parameter to chunk_hdr. */
660 union sctp_params param_hdr;
663 struct sctp_datahdr *data_hdr;
664 struct sctp_inithdr *init_hdr;
665 struct sctp_sackhdr *sack_hdr;
666 struct sctp_heartbeathdr *hb_hdr;
667 struct sctp_sender_hb_info *hbs_hdr;
668 struct sctp_shutdownhdr *shutdown_hdr;
669 struct sctp_signed_cookie *cookie_hdr;
670 struct sctp_ecnehdr *ecne_hdr;
671 struct sctp_cwrhdr *ecn_cwr_hdr;
672 struct sctp_errhdr *err_hdr;
673 struct sctp_addiphdr *addip_hdr;
674 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
679 struct sctp_chunkhdr *chunk_hdr;
680 struct sctphdr *sctp_hdr;
682 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
683 struct sctp_sndrcvinfo sinfo;
685 /* Which association does this belong to? */
686 struct sctp_association *asoc;
688 /* What endpoint received this chunk? */
689 struct sctp_ep_common *rcvr;
691 /* We fill this in if we are calculating RTT. */
692 unsigned long sent_at;
694 /* What is the origin IP address for this chunk? */
695 union sctp_addr source;
696 /* Destination address for this chunk. */
697 union sctp_addr dest;
699 /* For outbound message, track all fragments for SEND_FAILED. */
700 struct sctp_datamsg *msg;
702 /* For an inbound chunk, this tells us where it came from.
703 * For an outbound chunk, it tells us where we'd like it to
704 * go. It is NULL if we have no preference.
706 struct sctp_transport *transport;
708 __u8 rtt_in_progress; /* Is this chunk used for RTT calculation? */
709 __u8 resent; /* Has this chunk ever been retransmitted. */
710 __u8 has_tsn; /* Does this chunk have a TSN yet? */
711 __u8 has_ssn; /* Does this chunk have a SSN yet? */
712 __u8 singleton; /* Was this the only chunk in the packet? */
713 __u8 end_of_packet; /* Was this the last chunk in the packet? */
714 __u8 ecn_ce_done; /* Have we processed the ECN CE bit? */
715 __u8 pdiscard; /* Discard the whole packet now? */
716 __u8 tsn_gap_acked; /* Is this chunk acked by a GAP ACK? */
717 __s8 fast_retransmit; /* Is this chunk fast retransmitted? */
718 __u8 tsn_missing_report; /* Data chunk missing counter. */
719 __u8 data_accepted; /* At least 1 chunk in this packet accepted */
722 void sctp_chunk_hold(struct sctp_chunk *);
723 void sctp_chunk_put(struct sctp_chunk *);
724 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
726 void sctp_chunk_free(struct sctp_chunk *);
727 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
728 struct sctp_chunk *sctp_chunkify(struct sk_buff *,
729 const struct sctp_association *,
731 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
733 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
735 /* This is a structure for holding either an IPv6 or an IPv4 address. */
736 struct sctp_sockaddr_entry {
737 struct list_head list;
742 typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *);
744 /* This structure holds lists of chunks as we are assembling for
748 /* These are the SCTP header values (host order) for the packet. */
750 __u16 destination_port;
753 /* This contains the payload chunks. */
754 struct list_head chunk_list;
756 /* This is the overhead of the sctp and ip headers. */
758 /* This is the total size of all chunks INCLUDING padding. */
761 /* The packet is destined for this transport address.
762 * The function we finally use to pass down to the next lower
763 * layer lives in the transport structure.
765 struct sctp_transport *transport;
767 /* This packet contains a COOKIE-ECHO chunk. */
768 char has_cookie_echo;
770 /* This packet containsa SACK chunk. */
773 /* SCTP cannot fragment this packet. So let ip fragment it. */
779 struct sctp_packet *sctp_packet_init(struct sctp_packet *,
780 struct sctp_transport *,
781 __u16 sport, __u16 dport);
782 struct sctp_packet *sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
783 sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *,
784 struct sctp_chunk *);
785 sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *,
786 struct sctp_chunk *);
787 int sctp_packet_transmit(struct sctp_packet *);
788 void sctp_packet_free(struct sctp_packet *);
790 static inline int sctp_packet_empty(struct sctp_packet *packet)
792 return (packet->size == packet->overhead);
795 /* This represents a remote transport address.
796 * For local transport addresses, we just use union sctp_addr.
798 * RFC2960 Section 1.4 Key Terms
800 * o Transport address: A Transport Address is traditionally defined
801 * by Network Layer address, Transport Layer protocol and Transport
802 * Layer port number. In the case of SCTP running over IP, a
803 * transport address is defined by the combination of an IP address
804 * and an SCTP port number (where SCTP is the Transport protocol).
806 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
808 * o The sender keeps a separate congestion control parameter set for
809 * each of the destination addresses it can send to (not each
810 * source-destination pair but for each destination). The parameters
811 * should decay if the address is not used for a long enough time
815 struct sctp_transport {
816 /* A list of transports. */
817 struct list_head transports;
819 /* Reference counting. */
823 /* This is the peer's IP address and port. */
824 union sctp_addr ipaddr;
826 /* These are the functions we call to handle LLP stuff. */
827 struct sctp_af *af_specific;
829 /* Which association do we belong to? */
830 struct sctp_association *asoc;
834 * 12.3 Per Transport Address Data
836 * For each destination transport address in the peer's
837 * address list derived from the INIT or INIT ACK chunk, a
838 * number of data elements needs to be maintained including:
840 __u32 rtt; /* This is the most recent RTT. */
842 /* RTO : The current retransmission timeout value. */
845 /* RTTVAR : The current RTT variation. */
848 /* SRTT : The current smoothed round trip time. */
851 /* RTO-Pending : A flag used to track if one of the DATA
852 * chunks sent to this address is currently being
853 * used to compute a RTT. If this flag is 0,
854 * the next DATA chunk sent to this destination
855 * should be used to compute a RTT and this flag
856 * should be set. Every time the RTT
857 * calculation completes (i.e. the DATA chunk
858 * is SACK'd) clear this flag.
863 * These are the congestion stats.
865 /* cwnd : The current congestion window. */
866 __u32 cwnd; /* This is the actual cwnd. */
868 /* ssthresh : The current slow start threshold value. */
871 /* partial : The tracking method for increase of cwnd when in
872 * bytes acked : congestion avoidance mode (see Section 6.2.2)
874 __u32 partial_bytes_acked;
876 /* Data that has been sent, but not acknowledged. */
880 struct dst_entry *dst;
881 /* Source address. */
882 union sctp_addr saddr;
884 /* When was the last time(in jiffies) that a data packet was sent on
885 * this transport? This is used to adjust the cwnd when the transport
888 unsigned long last_time_used;
890 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
891 * the destination address every heartbeat interval.
893 unsigned long hbinterval;
895 /* SACK delay timeout */
896 unsigned long sackdelay;
898 /* When was the last time (in jiffies) that we heard from this
899 * transport? We use this to pick new active and retran paths.
901 unsigned long last_time_heard;
903 /* Last time(in jiffies) when cwnd is reduced due to the congestion
904 * indication based on ECNE chunk.
906 unsigned long last_time_ecne_reduced;
908 /* This is the max_retrans value for the transport and will
909 * be initialized from the assocs value. This can be changed
910 * using SCTP_SET_PEER_ADDR_PARAMS socket option.
914 /* PMTU : The current known path MTU. */
917 /* Flags controling Heartbeat, SACK delay, and Path MTU Discovery. */
920 /* The number of times INIT has been sent on this transport. */
923 /* state : The current state of this destination,
924 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKOWN.
928 /* These are the error stats for this destination. */
930 /* Error count : The current error count for this destination. */
931 unsigned short error_count;
933 /* Per : A timer used by each destination.
937 * [Everywhere else in the text this is called T3-rtx. -ed]
939 struct timer_list T3_rtx_timer;
941 /* Heartbeat timer is per destination. */
942 struct timer_list hb_timer;
944 /* Since we're using per-destination retransmission timers
945 * (see above), we're also using per-destination "transmitted"
946 * queues. This probably ought to be a private struct
947 * accessible only within the outqueue, but it's not, yet.
949 struct list_head transmitted;
951 /* We build bundle-able packets for this transport here. */
952 struct sctp_packet packet;
954 /* This is the list of transports that have chunks to send. */
955 struct list_head send_ready;
957 int malloced; /* Is this structure kfree()able? */
959 /* State information saved for SFR_CACC algorithm. The key
960 * idea in SFR_CACC is to maintain state at the sender on a
961 * per-destination basis when a changeover happens.
962 * char changeover_active;
963 * char cycling_changeover;
964 * __u32 next_tsn_at_change;
965 * char cacc_saw_newack;
968 /* An unsigned integer, which stores the next TSN to be
969 * used by the sender, at the moment of changeover.
971 __u32 next_tsn_at_change;
973 /* A flag which indicates the occurrence of a changeover */
974 char changeover_active;
976 /* A flag which indicates whether the change of primary is
977 * the first switch to this destination address during an
980 char cycling_changeover;
982 /* A temporary flag, which is used during the processing of
983 * a SACK to estimate the causative TSN(s)'s group.
985 char cacc_saw_newack;
988 /* 64-bit random number sent with heartbeat. */
992 struct sctp_transport *sctp_transport_new(const union sctp_addr *,
994 void sctp_transport_set_owner(struct sctp_transport *,
995 struct sctp_association *);
996 void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
998 void sctp_transport_pmtu(struct sctp_transport *);
999 void sctp_transport_free(struct sctp_transport *);
1000 void sctp_transport_reset_timers(struct sctp_transport *);
1001 void sctp_transport_hold(struct sctp_transport *);
1002 void sctp_transport_put(struct sctp_transport *);
1003 void sctp_transport_update_rto(struct sctp_transport *, __u32);
1004 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
1005 void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t);
1006 unsigned long sctp_transport_timeout(struct sctp_transport *);
1007 void sctp_transport_reset(struct sctp_transport *);
1010 /* This is the structure we use to queue packets as they come into
1011 * SCTP. We write packets to it and read chunks from it.
1014 /* This is actually a queue of sctp_chunk each
1015 * containing a partially decoded packet.
1017 struct list_head in_chunk_list;
1018 /* This is the packet which is currently off the in queue and is
1019 * being worked on through the inbound chunk processing.
1021 struct sctp_chunk *in_progress;
1023 /* This is the delayed task to finish delivering inbound
1026 struct work_struct immediate;
1028 int malloced; /* Is this structure kfree()able? */
1031 void sctp_inq_init(struct sctp_inq *);
1032 void sctp_inq_free(struct sctp_inq *);
1033 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
1034 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
1035 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t);
1037 /* This is the structure we use to hold outbound chunks. You push
1038 * chunks in and they automatically pop out the other end as bundled
1039 * packets (it calls (*output_handler)()).
1041 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1042 * and 8.2 of the v13 draft.
1044 * It handles retransmissions. The connection to the timeout portion
1045 * of the state machine is through sctp_..._timeout() and timeout_handler.
1047 * If you feed it SACKs, it will eat them.
1049 * If you give it big chunks, it will fragment them.
1051 * It assigns TSN's to data chunks. This happens at the last possible
1052 * instant before transmission.
1054 * When free()'d, it empties itself out via output_handler().
1057 struct sctp_association *asoc;
1059 /* Data pending that has never been transmitted. */
1060 struct list_head out_chunk_list;
1062 unsigned out_qlen; /* Total length of queued data chunks. */
1064 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1067 /* These are control chunks we want to send. */
1068 struct list_head control_chunk_list;
1070 /* These are chunks that have been sacked but are above the
1071 * CTSN, or cumulative tsn ack point.
1073 struct list_head sacked;
1075 /* Put chunks on this list to schedule them for
1078 struct list_head retransmit;
1080 /* Put chunks on this list to save them for FWD TSN processing as
1081 * they were abandoned.
1083 struct list_head abandoned;
1085 /* How many unackd bytes do we have in-flight? */
1086 __u32 outstanding_bytes;
1091 /* Is this structure empty? */
1094 /* Are we kfree()able? */
1098 void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1099 void sctp_outq_teardown(struct sctp_outq *);
1100 void sctp_outq_free(struct sctp_outq*);
1101 int sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk);
1102 int sctp_outq_flush(struct sctp_outq *, int);
1103 int sctp_outq_sack(struct sctp_outq *, struct sctp_sackhdr *);
1104 int sctp_outq_is_empty(const struct sctp_outq *);
1105 void sctp_outq_restart(struct sctp_outq *);
1107 void sctp_retransmit(struct sctp_outq *, struct sctp_transport *,
1108 sctp_retransmit_reason_t);
1109 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1110 int sctp_outq_uncork(struct sctp_outq *);
1111 /* Uncork and flush an outqueue. */
1112 static inline void sctp_outq_cork(struct sctp_outq *q)
1117 /* These bind address data fields common between endpoints and associations */
1118 struct sctp_bind_addr {
1120 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1122 * SCTP Port: The local SCTP port number the endpoint is
1127 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1129 * Address List: The list of IP addresses that this instance
1130 * has bound. This information is passed to one's
1131 * peer(s) in INIT and INIT ACK chunks.
1133 struct list_head address_list;
1135 int malloced; /* Are we kfree()able? */
1138 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1139 void sctp_bind_addr_free(struct sctp_bind_addr *);
1140 int sctp_bind_addr_copy(struct sctp_bind_addr *dest,
1141 const struct sctp_bind_addr *src,
1142 sctp_scope_t scope, gfp_t gfp,
1144 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1145 __u8 use_as_src, gfp_t gfp);
1146 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1147 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1148 struct sctp_sock *);
1149 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp,
1150 const union sctp_addr *addrs,
1152 struct sctp_sock *opt);
1153 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1156 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1157 __u16 port, gfp_t gfp);
1159 sctp_scope_t sctp_scope(const union sctp_addr *);
1160 int sctp_in_scope(const union sctp_addr *addr, const sctp_scope_t scope);
1161 int sctp_is_any(const union sctp_addr *addr);
1162 int sctp_addr_is_valid(const union sctp_addr *addr);
1165 /* What type of endpoint? */
1167 SCTP_EP_TYPE_SOCKET,
1168 SCTP_EP_TYPE_ASSOCIATION,
1169 } sctp_endpoint_type_t;
1172 * A common base class to bridge the implmentation view of a
1173 * socket (usually listening) endpoint versus an association's
1175 * This common structure is useful for several purposes:
1176 * 1) Common interface for lookup routines.
1177 * a) Subfunctions work for either endpoint or association
1178 * b) Single interface to lookup allows hiding the lookup lock rather
1179 * than acquiring it externally.
1180 * 2) Common interface for the inbound chunk handling/state machine.
1181 * 3) Common object handling routines for reference counting, etc.
1182 * 4) Disentangle association lookup from endpoint lookup, where we
1183 * do not have to find our endpoint to find our association.
1187 struct sctp_ep_common {
1188 /* Fields to help us manage our entries in the hash tables. */
1189 struct sctp_ep_common *next;
1190 struct sctp_ep_common **pprev;
1193 /* Runtime type information. What kind of endpoint is this? */
1194 sctp_endpoint_type_t type;
1196 /* Some fields to help us manage this object.
1197 * refcnt - Reference count access to this object.
1198 * dead - Do not attempt to use this object.
1199 * malloced - Do we need to kfree this object?
1205 /* What socket does this endpoint belong to? */
1208 /* This is where we receive inbound chunks. */
1209 struct sctp_inq inqueue;
1211 /* This substructure includes the defining parameters of the
1213 * bind_addr.port is our shared port number.
1214 * bind_addr.address_list is our set of local IP addresses.
1216 struct sctp_bind_addr bind_addr;
1218 /* Protection during address list comparisons. */
1223 /* RFC Section 1.4 Key Terms
1225 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1226 * multi-homed host, an SCTP endpoint is represented to its peers as a
1227 * combination of a set of eligible destination transport addresses to
1228 * which SCTP packets can be sent and a set of eligible source
1229 * transport addresses from which SCTP packets can be received.
1230 * All transport addresses used by an SCTP endpoint must use the
1231 * same port number, but can use multiple IP addresses. A transport
1232 * address used by an SCTP endpoint must not be used by another
1233 * SCTP endpoint. In other words, a transport address is unique
1234 * to an SCTP endpoint.
1236 * From an implementation perspective, each socket has one of these.
1237 * A TCP-style socket will have exactly one association on one of
1238 * these. An UDP-style socket will have multiple associations hanging
1242 struct sctp_endpoint {
1243 /* Common substructure for endpoint and association. */
1244 struct sctp_ep_common base;
1246 /* Associations: A list of current associations and mappings
1247 * to the data consumers for each association. This
1248 * may be in the form of a hash table or other
1249 * implementation dependent structure. The data
1250 * consumers may be process identification
1251 * information such as file descriptors, named pipe
1252 * pointer, or table pointers dependent on how SCTP
1255 /* This is really a list of struct sctp_association entries. */
1256 struct list_head asocs;
1258 /* Secret Key: A secret key used by this endpoint to compute
1259 * the MAC. This SHOULD be a cryptographic quality
1260 * random number with a sufficient length.
1261 * Discussion in [RFC1750] can be helpful in
1262 * selection of the key.
1264 __u8 secret_key[SCTP_HOW_MANY_SECRETS][SCTP_SECRET_SIZE];
1269 /* digest: This is a digest of the sctp cookie. This field is
1270 * only used on the receive path when we try to validate
1271 * that the cookie has not been tampered with. We put
1272 * this here so we pre-allocate this once and can re-use
1277 /* sendbuf acct. policy. */
1278 __u32 sndbuf_policy;
1280 /* rcvbuf acct. policy. */
1281 __u32 rcvbuf_policy;
1284 /* Recover the outter endpoint structure. */
1285 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1287 struct sctp_endpoint *ep;
1289 ep = container_of(base, struct sctp_endpoint, base);
1293 /* These are function signatures for manipulating endpoints. */
1294 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1295 void sctp_endpoint_free(struct sctp_endpoint *);
1296 void sctp_endpoint_put(struct sctp_endpoint *);
1297 void sctp_endpoint_hold(struct sctp_endpoint *);
1298 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1299 struct sctp_association *sctp_endpoint_lookup_assoc(
1300 const struct sctp_endpoint *ep,
1301 const union sctp_addr *paddr,
1302 struct sctp_transport **);
1303 int sctp_endpoint_is_peeled_off(struct sctp_endpoint *,
1304 const union sctp_addr *);
1305 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1306 const union sctp_addr *);
1307 int sctp_has_association(const union sctp_addr *laddr,
1308 const union sctp_addr *paddr);
1310 int sctp_verify_init(const struct sctp_association *asoc, sctp_cid_t,
1311 sctp_init_chunk_t *peer_init, struct sctp_chunk *chunk,
1312 struct sctp_chunk **err_chunk);
1313 int sctp_process_init(struct sctp_association *, sctp_cid_t cid,
1314 const union sctp_addr *peer,
1315 sctp_init_chunk_t *init, gfp_t gfp);
1316 __u32 sctp_generate_tag(const struct sctp_endpoint *);
1317 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
1319 struct sctp_inithdr_host {
1322 __u16 num_outbound_streams;
1323 __u16 num_inbound_streams;
1329 * 12. Recommended Transmission Control Block (TCB) Parameters
1331 * This section details a recommended set of parameters that should
1332 * be contained within the TCB for an implementation. This section is
1333 * for illustrative purposes and should not be deemed as requirements
1334 * on an implementation or as an exhaustive list of all parameters
1335 * inside an SCTP TCB. Each implementation may need its own additional
1336 * parameters for optimization.
1340 /* Here we have information about each individual association. */
1341 struct sctp_association {
1343 /* A base structure common to endpoint and association.
1344 * In this context, it represents the associations's view
1345 * of the local endpoint of the association.
1347 struct sctp_ep_common base;
1349 /* Associations on the same socket. */
1350 struct list_head asocs;
1352 /* association id. */
1353 sctp_assoc_t assoc_id;
1355 /* This is our parent endpoint. */
1356 struct sctp_endpoint *ep;
1358 /* These are those association elements needed in the cookie. */
1359 struct sctp_cookie c;
1361 /* This is all information about our peer. */
1365 * Peer Rwnd : Current calculated value of the peer's rwnd.
1369 /* transport_addr_list
1371 * Peer : A list of SCTP transport addresses that the
1372 * Transport : peer is bound to. This information is derived
1373 * Address : from the INIT or INIT ACK and is used to
1374 * List : associate an inbound packet with a given
1375 * : association. Normally this information is
1376 * : hashed or keyed for quick lookup and access
1378 * : The list is also initialized with the list
1379 * : of addresses passed with the sctp_connectx()
1382 * It is a list of SCTP_transport's.
1384 struct list_head transport_addr_list;
1388 * Peer : A count of the number of peer addresses
1389 * Transport : in the Peer Transport Address List.
1393 __u16 transport_count;
1396 * The transport layer port number.
1402 * Primary : This is the current primary destination
1403 * Path : transport address of the peer endpoint. It
1404 * : may also specify a source transport address
1405 * : on this endpoint.
1407 * All of these paths live on transport_addr_list.
1409 * At the bakeoffs, we discovered that the intent of
1410 * primaryPath is that it only changes when the ULP
1411 * asks to have it changed. We add the activePath to
1412 * designate the connection we are currently using to
1413 * transmit new data and most control chunks.
1415 struct sctp_transport *primary_path;
1417 /* Cache the primary path address here, when we
1418 * need a an address for msg_name.
1420 union sctp_addr primary_addr;
1423 * The path that we are currently using to
1424 * transmit new data and most control chunks.
1426 struct sctp_transport *active_path;
1430 * RFC2960 6.4 Multi-homed SCTP Endpoints
1432 * Furthermore, when its peer is multi-homed, an
1433 * endpoint SHOULD try to retransmit a chunk to an
1434 * active destination transport address that is
1435 * different from the last destination address to
1436 * which the DATA chunk was sent.
1438 struct sctp_transport *retran_path;
1440 /* Pointer to last transport I have sent on. */
1441 struct sctp_transport *last_sent_to;
1443 /* This is the last transport I have received DATA on. */
1444 struct sctp_transport *last_data_from;
1447 * Mapping An array of bits or bytes indicating which out of
1448 * Array order TSN's have been received (relative to the
1449 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1450 * order packets have been received, this array
1451 * will be set to all zero. This structure may be
1452 * in the form of a circular buffer or bit array.
1454 * Last Rcvd : This is the last TSN received in
1455 * TSN : sequence. This value is set initially by
1456 * : taking the peer's Initial TSN, received in
1457 * : the INIT or INIT ACK chunk, and subtracting
1460 * Throughout most of the specification this is called the
1461 * "Cumulative TSN ACK Point". In this case, we
1462 * ignore the advice in 12.2 in favour of the term
1463 * used in the bulk of the text. This value is hidden
1464 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1466 struct sctp_tsnmap tsn_map;
1467 __u8 _map[sctp_tsnmap_storage_size(SCTP_TSN_MAP_SIZE)];
1469 /* Ack State : This flag indicates if the next received
1470 * : packet is to be responded to with a
1471 * : SACK. This is initializedto 0. When a packet
1472 * : is received it is incremented. If this value
1473 * : reaches 2 or more, a SACK is sent and the
1474 * : value is reset to 0. Note: This is used only
1475 * : when no DATA chunks are received out of
1476 * : order. When DATA chunks are out of order,
1477 * : SACK's are not delayed (see Section 6).
1479 __u8 sack_needed; /* Do we need to sack the peer? */
1481 /* These are capabilities which our peer advertised. */
1482 __u8 ecn_capable; /* Can peer do ECN? */
1483 __u8 ipv4_address; /* Peer understands IPv4 addresses? */
1484 __u8 ipv6_address; /* Peer understands IPv6 addresses? */
1485 __u8 hostname_address;/* Peer understands DNS addresses? */
1486 __u8 asconf_capable; /* Does peer support ADDIP? */
1487 __u8 prsctp_capable; /* Can peer do PR-SCTP? */
1489 __u32 adaptation_ind; /* Adaptation Code point. */
1491 /* This mask is used to disable sending the ASCONF chunk
1492 * with specified parameter to peer.
1494 __be16 addip_disabled_mask;
1496 struct sctp_inithdr_host i;
1500 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1501 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1502 * Initial TSN Value minus 1
1507 /* State : A state variable indicating what state the
1508 * : association is in, i.e. COOKIE-WAIT,
1509 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1510 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1512 * Note: No "CLOSED" state is illustrated since if a
1513 * association is "CLOSED" its TCB SHOULD be removed.
1515 * In this implementation we DO have a CLOSED
1516 * state which is used during initiation and shutdown.
1518 * State takes values from SCTP_STATE_*.
1522 /* The cookie life I award for any cookie. */
1523 struct timeval cookie_life;
1525 /* Overall : The overall association error count.
1526 * Error Count : [Clear this any time I get something.]
1528 int overall_error_count;
1530 /* These are the association's initial, max, and min RTO values.
1531 * These values will be initialized by system defaults, but can
1532 * be modified via the SCTP_RTOINFO socket option.
1534 unsigned long rto_initial;
1535 unsigned long rto_max;
1536 unsigned long rto_min;
1538 /* Maximum number of new data packets that can be sent in a burst. */
1541 /* This is the max_retrans value for the association. This value will
1542 * be initialized initialized from system defaults, but can be
1543 * modified by the SCTP_ASSOCINFO socket option.
1547 /* Maximum number of times the endpoint will retransmit INIT */
1548 __u16 max_init_attempts;
1550 /* How many times have we resent an INIT? */
1553 /* The largest timeout or RTO value to use in attempting an INIT */
1554 unsigned long max_init_timeo;
1556 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1557 * the destination address every heartbeat interval. This value
1558 * will be inherited by all new transports.
1560 unsigned long hbinterval;
1562 /* This is the max_retrans value for new transports in the
1567 /* Association : The smallest PMTU discovered for all of the
1568 * PMTU : peer's transport addresses.
1572 /* Flags controling Heartbeat, SACK delay, and Path MTU Discovery. */
1575 /* SACK delay timeout */
1576 unsigned long sackdelay;
1579 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES];
1580 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1582 /* Transport to which SHUTDOWN chunk was last sent. */
1583 struct sctp_transport *shutdown_last_sent_to;
1585 /* Transport to which INIT chunk was last sent. */
1586 struct sctp_transport *init_last_sent_to;
1588 /* Next TSN : The next TSN number to be assigned to a new
1589 * : DATA chunk. This is sent in the INIT or INIT
1590 * : ACK chunk to the peer and incremented each
1591 * : time a DATA chunk is assigned a TSN
1592 * : (normally just prior to transmit or during
1598 * Last Rcvd : This is the last TSN received in sequence. This value
1599 * TSN : is set initially by taking the peer's Initial TSN,
1600 * : received in the INIT or INIT ACK chunk, and
1601 * : subtracting one from it.
1603 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1606 __u32 ctsn_ack_point;
1608 /* PR-SCTP Advanced.Peer.Ack.Point */
1609 __u32 adv_peer_ack_point;
1611 /* Highest TSN that is acknowledged by incoming SACKs. */
1612 __u32 highest_sacked;
1614 /* The number of unacknowledged data chunks. Reported through
1615 * the SCTP_STATUS sockopt.
1619 /* This is the association's receive buffer space. This value is used
1620 * to set a_rwnd field in an INIT or a SACK chunk.
1624 /* This is the last advertised value of rwnd over a SACK chunk. */
1627 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1628 * to slop over a maximum of the association's frag_point.
1632 /* This is the sndbuf size in use for the association.
1633 * This corresponds to the sndbuf size for the association,
1634 * as specified in the sk->sndbuf.
1638 /* This is the amount of memory that this association has allocated
1639 * in the receive path at any given time.
1641 atomic_t rmem_alloc;
1643 /* This is the wait queue head for send requests waiting on
1644 * the association sndbuf space.
1646 wait_queue_head_t wait;
1648 /* The message size at which SCTP fragmentation will occur. */
1651 /* Counter used to count INIT errors. */
1652 int init_err_counter;
1654 /* Count the number of INIT cycles (for doubling timeout). */
1657 /* Default send parameters. */
1658 __u16 default_stream;
1659 __u16 default_flags;
1661 __u32 default_context;
1662 __u32 default_timetolive;
1664 /* Default receive parameters */
1665 __u32 default_rcv_context;
1667 /* This tracks outbound ssn for a given stream. */
1668 struct sctp_ssnmap *ssnmap;
1670 /* All outbound chunks go through this structure. */
1671 struct sctp_outq outqueue;
1673 /* A smart pipe that will handle reordering and fragmentation,
1674 * as well as handle passing events up to the ULP.
1676 struct sctp_ulpq ulpq;
1678 /* Last TSN that caused an ECNE Chunk to be sent. */
1679 __u32 last_ecne_tsn;
1681 /* Last TSN that caused a CWR Chunk to be sent. */
1684 /* How many duplicated TSNs have we seen? */
1687 /* Number of seconds of idle time before an association is closed.
1688 * In the association context, this is really used as a boolean
1689 * since the real timeout is stored in the timeouts array
1693 /* These are to support
1694 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1695 * and Enforcement of Flow and Message Limits"
1696 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1697 * or "ADDIP" for short.
1702 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1704 * R1) One and only one ASCONF Chunk MAY be in transit and
1705 * unacknowledged at any one time. If a sender, after sending
1706 * an ASCONF chunk, decides it needs to transfer another
1707 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1708 * returns from the previous ASCONF Chunk before sending a
1709 * subsequent ASCONF. Note this restriction binds each side,
1710 * so at any time two ASCONF may be in-transit on any given
1711 * association (one sent from each endpoint).
1713 * [This is our one-and-only-one ASCONF in flight. If we do
1714 * not have an ASCONF in flight, this is NULL.]
1716 struct sctp_chunk *addip_last_asconf;
1718 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1720 * IMPLEMENTATION NOTE: As an optimization a receiver may wish
1721 * to save the last ASCONF-ACK for some predetermined period
1722 * of time and instead of re-processing the ASCONF (with the
1723 * same serial number) it may just re-transmit the
1724 * ASCONF-ACK. It may wish to use the arrival of a new serial
1725 * number to discard the previously saved ASCONF-ACK or any
1726 * other means it may choose to expire the saved ASCONF-ACK.
1728 * [This is our saved ASCONF-ACK. We invalidate it when a new
1729 * ASCONF serial number arrives.]
1731 struct sctp_chunk *addip_last_asconf_ack;
1733 /* These ASCONF chunks are waiting to be sent.
1735 * These chunaks can't be pushed to outqueue until receiving
1736 * ASCONF_ACK for the previous ASCONF indicated by
1737 * addip_last_asconf, so as to guarantee that only one ASCONF
1738 * is in flight at any time.
1740 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1742 * In defining the ASCONF Chunk transfer procedures, it is
1743 * essential that these transfers MUST NOT cause congestion
1744 * within the network. To achieve this, we place these
1745 * restrictions on the transfer of ASCONF Chunks:
1747 * R1) One and only one ASCONF Chunk MAY be in transit and
1748 * unacknowledged at any one time. If a sender, after sending
1749 * an ASCONF chunk, decides it needs to transfer another
1750 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1751 * returns from the previous ASCONF Chunk before sending a
1752 * subsequent ASCONF. Note this restriction binds each side,
1753 * so at any time two ASCONF may be in-transit on any given
1754 * association (one sent from each endpoint).
1757 * [I really think this is EXACTLY the sort of intelligence
1758 * which already resides in sctp_outq. Please move this
1759 * queue and its supporting logic down there. --piggy]
1761 struct list_head addip_chunk_list;
1763 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1765 * A2) A serial number should be assigned to the Chunk. The
1766 * serial number SHOULD be a monotonically increasing
1767 * number. The serial number SHOULD be initialized at
1768 * the start of the association to the same value as the
1769 * Initial TSN and every time a new ASCONF chunk is created
1770 * it is incremented by one after assigning the serial number
1771 * to the newly created chunk.
1774 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
1776 * Serial Number : 32 bits (unsigned integer)
1778 * This value represents a Serial Number for the ASCONF
1779 * Chunk. The valid range of Serial Number is from 0 to
1780 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
1781 * after reaching 4294967295.
1785 /* Need to send an ECNE Chunk? */
1788 /* Is it a temporary association? */
1793 /* An eyecatcher for determining if we are really looking at an
1794 * association data structure.
1797 SCTP_ASSOC_EYECATCHER = 0xa550c123,
1800 /* Recover the outter association structure. */
1801 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
1803 struct sctp_association *asoc;
1805 asoc = container_of(base, struct sctp_association, base);
1809 /* These are function signatures for manipulating associations. */
1812 struct sctp_association *
1813 sctp_association_new(const struct sctp_endpoint *, const struct sock *,
1814 sctp_scope_t scope, gfp_t gfp);
1815 void sctp_association_free(struct sctp_association *);
1816 void sctp_association_put(struct sctp_association *);
1817 void sctp_association_hold(struct sctp_association *);
1819 struct sctp_transport *sctp_assoc_choose_init_transport(
1820 struct sctp_association *);
1821 struct sctp_transport *sctp_assoc_choose_shutdown_transport(
1822 struct sctp_association *);
1823 void sctp_assoc_update_retran_path(struct sctp_association *);
1824 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
1825 const union sctp_addr *);
1826 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1827 const union sctp_addr *laddr);
1828 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
1829 const union sctp_addr *address,
1831 const int peer_state);
1832 void sctp_assoc_del_peer(struct sctp_association *asoc,
1833 const union sctp_addr *addr);
1834 void sctp_assoc_rm_peer(struct sctp_association *asoc,
1835 struct sctp_transport *peer);
1836 void sctp_assoc_control_transport(struct sctp_association *,
1837 struct sctp_transport *,
1838 sctp_transport_cmd_t, sctp_sn_error_t);
1839 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
1840 struct sctp_transport *sctp_assoc_is_match(struct sctp_association *,
1841 const union sctp_addr *,
1842 const union sctp_addr *);
1843 void sctp_assoc_migrate(struct sctp_association *, struct sock *);
1844 void sctp_assoc_update(struct sctp_association *old,
1845 struct sctp_association *new);
1847 __u32 sctp_association_get_next_tsn(struct sctp_association *);
1849 void sctp_assoc_sync_pmtu(struct sctp_association *);
1850 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned);
1851 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned);
1852 void sctp_assoc_set_primary(struct sctp_association *,
1853 struct sctp_transport *);
1854 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *,
1856 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
1857 struct sctp_cookie*,
1860 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1861 const union sctp_addr *ss2);
1862 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
1864 /* A convenience structure to parse out SCTP specific CMSGs. */
1865 typedef struct sctp_cmsgs {
1866 struct sctp_initmsg *init;
1867 struct sctp_sndrcvinfo *info;
1870 /* Structure for tracking memory objects */
1874 } sctp_dbg_objcnt_entry_t;
1876 #endif /* __sctp_structs_h__ */