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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* 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.
6 *
7 * This file is part of the SCTP kernel reference Implementation
8 *
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)
13 * any later version.
14 *
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.
20 *
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.
25 *
26 * Please send any bug reports or fixes you make to the
27 * email addresses:
28 * lksctp developers <lksctp-developers@lists.sourceforge.net>
29 *
30 * Or submit a bug report through the following website:
31 * http://www.sf.net/projects/lksctp
32 *
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>
49 *
50 * Any bugs reported given to us we will try to fix... any fixes shared will
51 * be incorporated into the next SCTP release.
52 */
53
54#ifndef __sctp_structs_h__
55#define __sctp_structs_h__
56
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
68/* A convenience structure for handling sockaddr structures.
69 * We should wean ourselves off this.
70 */
71union sctp_addr {
72 struct sockaddr_in v4;
73 struct sockaddr_in6 v6;
74 struct sockaddr sa;
75};
76
77/* Forward declarations for data structures. */
78struct sctp_globals;
79struct sctp_endpoint;
80struct sctp_association;
81struct sctp_transport;
82struct sctp_packet;
83struct sctp_chunk;
84struct sctp_inq;
85struct sctp_outq;
86struct sctp_bind_addr;
87struct sctp_ulpq;
88struct sctp_ep_common;
89struct sctp_ssnmap;
90
91
92#include <net/sctp/tsnmap.h>
93#include <net/sctp/ulpevent.h>
94#include <net/sctp/ulpqueue.h>
95
96/* Structures useful for managing bind/connect. */
97
98struct sctp_bind_bucket {
99 unsigned short port;
100 unsigned short fastreuse;
101 struct sctp_bind_bucket *next;
102 struct sctp_bind_bucket **pprev;
103 struct hlist_head owner;
104};
105
106struct sctp_bind_hashbucket {
107 spinlock_t lock;
108 struct sctp_bind_bucket *chain;
109};
110
111/* Used for hashing all associations. */
112struct sctp_hashbucket {
113 rwlock_t lock;
114 struct sctp_ep_common *chain;
115} __attribute__((__aligned__(8)));
116
117
118/* The SCTP globals structure. */
119extern struct sctp_globals {
120 /* RFC2960 Section 14. Suggested SCTP Protocol Parameter Values
121 *
122 * The following protocol parameters are RECOMMENDED:
123 *
124 * RTO.Initial - 3 seconds
125 * RTO.Min - 1 second
126 * RTO.Max - 60 seconds
127 * RTO.Alpha - 1/8 (3 when converted to right shifts.)
128 * RTO.Beta - 1/4 (2 when converted to right shifts.)
129 */
130 __u32 rto_initial;
131 __u32 rto_min;
132 __u32 rto_max;
133
134 /* Note: rto_alpha and rto_beta are really defined as inverse
135 * powers of two to facilitate integer operations.
136 */
137 int rto_alpha;
138 int rto_beta;
139
140 /* Max.Burst - 4 */
141 int max_burst;
142
143 /* Valid.Cookie.Life - 60 seconds */
144 int valid_cookie_life;
145
146 /* Whether Cookie Preservative is enabled(1) or not(0) */
147 int cookie_preserve_enable;
148
149 /* Association.Max.Retrans - 10 attempts
150 * Path.Max.Retrans - 5 attempts (per destination address)
151 * Max.Init.Retransmits - 8 attempts
152 */
153 int max_retrans_association;
154 int max_retrans_path;
155 int max_retrans_init;
156
Neil Horman4eb701d2005-04-28 12:02:04 -0700157 /*
158 * Policy for preforming sctp/socket accounting
159 * 0 - do socket level accounting, all assocs share sk_sndbuf
160 * 1 - do sctp accounting, each asoc may use sk_sndbuf bytes
161 */
162 int sndbuf_policy;
163
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164 /* HB.interval - 30 seconds */
165 int hb_interval;
166
167 /* The following variables are implementation specific. */
168
169 /* Default initialization values to be applied to new associations. */
170 __u16 max_instreams;
171 __u16 max_outstreams;
172
173 /* This is a list of groups of functions for each address
174 * family that we support.
175 */
176 struct list_head address_families;
177
178 /* This is the hash of all endpoints. */
179 int ep_hashsize;
180 struct sctp_hashbucket *ep_hashtable;
181
182 /* This is the hash of all associations. */
183 int assoc_hashsize;
184 struct sctp_hashbucket *assoc_hashtable;
185
186 /* This is the sctp port control hash. */
187 int port_hashsize;
188 int port_rover;
189 spinlock_t port_alloc_lock; /* Protects port_rover. */
190 struct sctp_bind_hashbucket *port_hashtable;
191
192 /* This is the global local address list.
193 * We actively maintain this complete list of interfaces on
194 * the system by catching routing events.
195 *
196 * It is a list of sctp_sockaddr_entry.
197 */
198 struct list_head local_addr_list;
199 spinlock_t local_addr_lock;
200
201 /* Flag to indicate if addip is enabled. */
202 int addip_enable;
203
204 /* Flag to indicate if PR-SCTP is enabled. */
205 int prsctp_enable;
206} sctp_globals;
207
208#define sctp_rto_initial (sctp_globals.rto_initial)
209#define sctp_rto_min (sctp_globals.rto_min)
210#define sctp_rto_max (sctp_globals.rto_max)
211#define sctp_rto_alpha (sctp_globals.rto_alpha)
212#define sctp_rto_beta (sctp_globals.rto_beta)
213#define sctp_max_burst (sctp_globals.max_burst)
214#define sctp_valid_cookie_life (sctp_globals.valid_cookie_life)
215#define sctp_cookie_preserve_enable (sctp_globals.cookie_preserve_enable)
216#define sctp_max_retrans_association (sctp_globals.max_retrans_association)
Neil Horman4eb701d2005-04-28 12:02:04 -0700217#define sctp_sndbuf_policy (sctp_globals.sndbuf_policy)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218#define sctp_max_retrans_path (sctp_globals.max_retrans_path)
219#define sctp_max_retrans_init (sctp_globals.max_retrans_init)
220#define sctp_hb_interval (sctp_globals.hb_interval)
221#define sctp_max_instreams (sctp_globals.max_instreams)
222#define sctp_max_outstreams (sctp_globals.max_outstreams)
223#define sctp_address_families (sctp_globals.address_families)
224#define sctp_ep_hashsize (sctp_globals.ep_hashsize)
225#define sctp_ep_hashtable (sctp_globals.ep_hashtable)
226#define sctp_assoc_hashsize (sctp_globals.assoc_hashsize)
227#define sctp_assoc_hashtable (sctp_globals.assoc_hashtable)
228#define sctp_port_hashsize (sctp_globals.port_hashsize)
229#define sctp_port_rover (sctp_globals.port_rover)
230#define sctp_port_alloc_lock (sctp_globals.port_alloc_lock)
231#define sctp_port_hashtable (sctp_globals.port_hashtable)
232#define sctp_local_addr_list (sctp_globals.local_addr_list)
233#define sctp_local_addr_lock (sctp_globals.local_addr_lock)
234#define sctp_addip_enable (sctp_globals.addip_enable)
235#define sctp_prsctp_enable (sctp_globals.prsctp_enable)
236
237/* SCTP Socket type: UDP or TCP style. */
238typedef enum {
239 SCTP_SOCKET_UDP = 0,
240 SCTP_SOCKET_UDP_HIGH_BANDWIDTH,
241 SCTP_SOCKET_TCP
242} sctp_socket_type_t;
243
244/* Per socket SCTP information. */
245struct sctp_sock {
246 /* inet_sock has to be the first member of sctp_sock */
247 struct inet_sock inet;
248 /* What kind of a socket is this? */
249 sctp_socket_type_t type;
250
251 /* PF_ family specific functions. */
252 struct sctp_pf *pf;
253
254 /* Access to HMAC transform. */
255 struct crypto_tfm *hmac;
256
257 /* What is our base endpointer? */
258 struct sctp_endpoint *ep;
259
260 struct sctp_bind_bucket *bind_hash;
261 /* Various Socket Options. */
262 __u16 default_stream;
263 __u32 default_ppid;
264 __u16 default_flags;
265 __u32 default_context;
266 __u32 default_timetolive;
267
268 struct sctp_initmsg initmsg;
269 struct sctp_rtoinfo rtoinfo;
270 struct sctp_paddrparams paddrparam;
271 struct sctp_event_subscribe subscribe;
272 struct sctp_assocparams assocparams;
273 int user_frag;
274 __u32 autoclose;
275 __u8 nodelay;
276 __u8 disable_fragments;
277 __u8 pd_mode;
278 __u8 v4mapped;
279 __u32 adaption_ind;
280
281 /* Receive to here while partial delivery is in effect. */
282 struct sk_buff_head pd_lobby;
283};
284
285static inline struct sctp_sock *sctp_sk(const struct sock *sk)
286{
287 return (struct sctp_sock *)sk;
288}
289
290static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
291{
292 return (struct sock *)sp;
293}
294
295#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
296struct sctp6_sock {
297 struct sctp_sock sctp;
298 struct ipv6_pinfo inet6;
299};
300#endif /* CONFIG_IPV6 */
301
302
303/* This is our APPLICATION-SPECIFIC state cookie.
304 * THIS IS NOT DICTATED BY THE SPECIFICATION.
305 */
306/* These are the parts of an association which we send in the cookie.
307 * Most of these are straight out of:
308 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
309 *
310 */
311
312struct sctp_cookie {
313
314 /* My : Tag expected in every inbound packet and sent
315 * Verification: in the INIT or INIT ACK chunk.
316 * Tag :
317 */
318 __u32 my_vtag;
319
320 /* Peer's : Tag expected in every outbound packet except
321 * Verification: in the INIT chunk.
322 * Tag :
323 */
324 __u32 peer_vtag;
325
326 /* The rest of these are not from the spec, but really need to
327 * be in the cookie.
328 */
329
330 /* My Tie Tag : Assist in discovering a restarting association. */
331 __u32 my_ttag;
332
333 /* Peer's Tie Tag: Assist in discovering a restarting association. */
334 __u32 peer_ttag;
335
336 /* When does this cookie expire? */
337 struct timeval expiration;
338
339 /* Number of inbound/outbound streams which are set
340 * and negotiated during the INIT process.
341 */
342 __u16 sinit_num_ostreams;
343 __u16 sinit_max_instreams;
344
345 /* This is the first sequence number I used. */
346 __u32 initial_tsn;
347
348 /* This holds the originating address of the INIT packet. */
349 union sctp_addr peer_addr;
350
351 /* IG Section 2.35.3
352 * Include the source port of the INIT-ACK
353 */
354 __u16 my_port;
355
356 __u8 prsctp_capable;
357
358 /* Padding for future use */
359 __u8 padding;
360
361 __u32 adaption_ind;
362
363
364 /* This is a shim for my peer's INIT packet, followed by
365 * a copy of the raw address list of the association.
366 * The length of the raw address list is saved in the
367 * raw_addr_list_len field, which will be used at the time when
368 * the association TCB is re-constructed from the cookie.
369 */
370 __u32 raw_addr_list_len;
371 struct sctp_init_chunk peer_init[0];
372};
373
374
375/* The format of our cookie that we send to our peer. */
376struct sctp_signed_cookie {
377 __u8 signature[SCTP_SECRET_SIZE];
378 struct sctp_cookie c;
379};
380
381/* This is another convenience type to allocate memory for address
382 * params for the maximum size and pass such structures around
383 * internally.
384 */
385union sctp_addr_param {
386 struct sctp_ipv4addr_param v4;
387 struct sctp_ipv6addr_param v6;
388};
389
390/* A convenience type to allow walking through the various
391 * parameters and avoid casting all over the place.
392 */
393union sctp_params {
394 void *v;
395 struct sctp_paramhdr *p;
396 struct sctp_cookie_preserve_param *life;
397 struct sctp_hostname_param *dns;
398 struct sctp_cookie_param *cookie;
399 struct sctp_supported_addrs_param *sat;
400 struct sctp_ipv4addr_param *v4;
401 struct sctp_ipv6addr_param *v6;
402 union sctp_addr_param *addr;
403 struct sctp_adaption_ind_param *aind;
404};
405
406/* RFC 2960. Section 3.3.5 Heartbeat.
407 * Heartbeat Information: variable length
408 * The Sender-specific Heartbeat Info field should normally include
409 * information about the sender's current time when this HEARTBEAT
410 * chunk is sent and the destination transport address to which this
411 * HEARTBEAT is sent (see Section 8.3).
412 */
413typedef struct sctp_sender_hb_info {
414 struct sctp_paramhdr param_hdr;
415 union sctp_addr daddr;
416 unsigned long sent_at;
417} __attribute__((packed)) sctp_sender_hb_info_t;
418
419/*
420 * RFC 2960 1.3.2 Sequenced Delivery within Streams
421 *
422 * The term "stream" is used in SCTP to refer to a sequence of user
423 * messages that are to be delivered to the upper-layer protocol in
424 * order with respect to other messages within the same stream. This is
425 * in contrast to its usage in TCP, where it refers to a sequence of
426 * bytes (in this document a byte is assumed to be eight bits).
427 * ...
428 *
429 * This is the structure we use to track both our outbound and inbound
430 * SSN, or Stream Sequence Numbers.
431 */
432
433struct sctp_stream {
434 __u16 *ssn;
435 unsigned int len;
436};
437
438struct sctp_ssnmap {
439 struct sctp_stream in;
440 struct sctp_stream out;
441 int malloced;
442};
443
444struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out, int gfp);
445void sctp_ssnmap_free(struct sctp_ssnmap *map);
446void sctp_ssnmap_clear(struct sctp_ssnmap *map);
447
448/* What is the current SSN number for this stream? */
449static inline __u16 sctp_ssn_peek(struct sctp_stream *stream, __u16 id)
450{
451 return stream->ssn[id];
452}
453
454/* Return the next SSN number for this stream. */
455static inline __u16 sctp_ssn_next(struct sctp_stream *stream, __u16 id)
456{
457 return stream->ssn[id]++;
458}
459
460/* Skip over this ssn and all below. */
461static inline void sctp_ssn_skip(struct sctp_stream *stream, __u16 id,
462 __u16 ssn)
463{
464 stream->ssn[id] = ssn+1;
465}
466
467/*
468 * Pointers to address related SCTP functions.
469 * (i.e. things that depend on the address family.)
470 */
471struct sctp_af {
472 int (*sctp_xmit) (struct sk_buff *skb,
473 struct sctp_transport *,
474 int ipfragok);
475 int (*setsockopt) (struct sock *sk,
476 int level,
477 int optname,
478 char __user *optval,
479 int optlen);
480 int (*getsockopt) (struct sock *sk,
481 int level,
482 int optname,
483 char __user *optval,
484 int __user *optlen);
485 struct dst_entry *(*get_dst) (struct sctp_association *asoc,
486 union sctp_addr *daddr,
487 union sctp_addr *saddr);
488 void (*get_saddr) (struct sctp_association *asoc,
489 struct dst_entry *dst,
490 union sctp_addr *daddr,
491 union sctp_addr *saddr);
492 void (*copy_addrlist) (struct list_head *,
493 struct net_device *);
494 void (*dst_saddr) (union sctp_addr *saddr,
495 struct dst_entry *dst,
496 unsigned short port);
497 int (*cmp_addr) (const union sctp_addr *addr1,
498 const union sctp_addr *addr2);
499 void (*addr_copy) (union sctp_addr *dst,
500 union sctp_addr *src);
501 void (*from_skb) (union sctp_addr *,
502 struct sk_buff *skb,
503 int saddr);
504 void (*from_sk) (union sctp_addr *,
505 struct sock *sk);
506 void (*to_sk_saddr) (union sctp_addr *,
507 struct sock *sk);
508 void (*to_sk_daddr) (union sctp_addr *,
509 struct sock *sk);
510 void (*from_addr_param) (union sctp_addr *,
511 union sctp_addr_param *,
512 __u16 port, int iif);
513 int (*to_addr_param) (const union sctp_addr *,
514 union sctp_addr_param *);
515 int (*addr_valid) (union sctp_addr *,
516 struct sctp_sock *);
517 sctp_scope_t (*scope) (union sctp_addr *);
518 void (*inaddr_any) (union sctp_addr *, unsigned short);
519 int (*is_any) (const union sctp_addr *);
520 int (*available) (union sctp_addr *,
521 struct sctp_sock *);
522 int (*skb_iif) (const struct sk_buff *sk);
523 int (*is_ce) (const struct sk_buff *sk);
524 void (*seq_dump_addr)(struct seq_file *seq,
525 union sctp_addr *addr);
526 __u16 net_header_len;
527 int sockaddr_len;
528 sa_family_t sa_family;
529 struct list_head list;
530};
531
532struct sctp_af *sctp_get_af_specific(sa_family_t);
533int sctp_register_af(struct sctp_af *);
534
535/* Protocol family functions. */
536struct sctp_pf {
537 void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
538 void (*skb_msgname) (struct sk_buff *, char *, int *);
539 int (*af_supported) (sa_family_t, struct sctp_sock *);
540 int (*cmp_addr) (const union sctp_addr *,
541 const union sctp_addr *,
542 struct sctp_sock *);
543 int (*bind_verify) (struct sctp_sock *, union sctp_addr *);
544 int (*send_verify) (struct sctp_sock *, union sctp_addr *);
545 int (*supported_addrs)(const struct sctp_sock *, __u16 *);
546 struct sock *(*create_accept_sk) (struct sock *sk,
547 struct sctp_association *asoc);
548 void (*addr_v4map) (struct sctp_sock *, union sctp_addr *);
549 struct sctp_af *af;
550};
551
552
553/* Structure to track chunk fragments that have been acked, but peer
554 * fragments of the same message have not.
555 */
556struct sctp_datamsg {
557 /* Chunks waiting to be submitted to lower layer. */
558 struct list_head chunks;
559 /* Chunks that have been transmitted. */
560 struct list_head track;
561 /* Reference counting. */
562 atomic_t refcnt;
563 /* When is this message no longer interesting to the peer? */
564 unsigned long expires_at;
565 /* Did the messenge fail to send? */
566 int send_error;
567 char send_failed;
568 /* Control whether chunks from this message can be abandoned. */
569 char can_abandon;
570};
571
572struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
573 struct sctp_sndrcvinfo *,
574 struct msghdr *, int len);
575void sctp_datamsg_put(struct sctp_datamsg *);
576void sctp_datamsg_free(struct sctp_datamsg *);
577void sctp_datamsg_track(struct sctp_chunk *);
578void sctp_chunk_fail(struct sctp_chunk *, int error);
579int sctp_chunk_abandoned(struct sctp_chunk *);
580
581
582/* RFC2960 1.4 Key Terms
583 *
584 * o Chunk: A unit of information within an SCTP packet, consisting of
585 * a chunk header and chunk-specific content.
586 *
587 * As a matter of convenience, we remember the SCTP common header for
588 * each chunk as well as a few other header pointers...
589 */
590struct sctp_chunk {
591 /* These first three elements MUST PRECISELY match the first
592 * three elements of struct sk_buff. This allows us to reuse
593 * all the skb_* queue management functions.
594 */
595 struct sctp_chunk *next;
596 struct sctp_chunk *prev;
597 struct sk_buff_head *list;
598 atomic_t refcnt;
599
600 /* This is our link to the per-transport transmitted list. */
601 struct list_head transmitted_list;
602
603 /* This field is used by chunks that hold fragmented data.
604 * For the first fragment this is the list that holds the rest of
605 * fragments. For the remaining fragments, this is the link to the
606 * frag_list maintained in the first fragment.
607 */
608 struct list_head frag_list;
609
610 /* This points to the sk_buff containing the actual data. */
611 struct sk_buff *skb;
612
613 /* These are the SCTP headers by reverse order in a packet.
614 * Note that some of these may happen more than once. In that
615 * case, we point at the "current" one, whatever that means
616 * for that level of header.
617 */
618
619 /* We point this at the FIRST TLV parameter to chunk_hdr. */
620 union sctp_params param_hdr;
621 union {
622 __u8 *v;
623 struct sctp_datahdr *data_hdr;
624 struct sctp_inithdr *init_hdr;
625 struct sctp_sackhdr *sack_hdr;
626 struct sctp_heartbeathdr *hb_hdr;
627 struct sctp_sender_hb_info *hbs_hdr;
628 struct sctp_shutdownhdr *shutdown_hdr;
629 struct sctp_signed_cookie *cookie_hdr;
630 struct sctp_ecnehdr *ecne_hdr;
631 struct sctp_cwrhdr *ecn_cwr_hdr;
632 struct sctp_errhdr *err_hdr;
633 struct sctp_addiphdr *addip_hdr;
634 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
635 } subh;
636
637 __u8 *chunk_end;
638
639 struct sctp_chunkhdr *chunk_hdr;
640 struct sctphdr *sctp_hdr;
641
642 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
643 struct sctp_sndrcvinfo sinfo;
644
645 /* Which association does this belong to? */
646 struct sctp_association *asoc;
647
648 /* What endpoint received this chunk? */
649 struct sctp_ep_common *rcvr;
650
651 /* We fill this in if we are calculating RTT. */
652 unsigned long sent_at;
653
654 /* What is the origin IP address for this chunk? */
655 union sctp_addr source;
656 /* Destination address for this chunk. */
657 union sctp_addr dest;
658
659 /* For outbound message, track all fragments for SEND_FAILED. */
660 struct sctp_datamsg *msg;
661
662 /* For an inbound chunk, this tells us where it came from.
663 * For an outbound chunk, it tells us where we'd like it to
664 * go. It is NULL if we have no preference.
665 */
666 struct sctp_transport *transport;
667
668 __u8 rtt_in_progress; /* Is this chunk used for RTT calculation? */
669 __u8 resent; /* Has this chunk ever been retransmitted. */
670 __u8 has_tsn; /* Does this chunk have a TSN yet? */
671 __u8 has_ssn; /* Does this chunk have a SSN yet? */
672 __u8 singleton; /* Was this the only chunk in the packet? */
673 __u8 end_of_packet; /* Was this the last chunk in the packet? */
674 __u8 ecn_ce_done; /* Have we processed the ECN CE bit? */
675 __u8 pdiscard; /* Discard the whole packet now? */
676 __u8 tsn_gap_acked; /* Is this chunk acked by a GAP ACK? */
677 __u8 fast_retransmit; /* Is this chunk fast retransmitted? */
678 __u8 tsn_missing_report; /* Data chunk missing counter. */
679};
680
681void sctp_chunk_hold(struct sctp_chunk *);
682void sctp_chunk_put(struct sctp_chunk *);
683int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
684 struct iovec *data);
685void sctp_chunk_free(struct sctp_chunk *);
686void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
687struct sctp_chunk *sctp_chunkify(struct sk_buff *,
688 const struct sctp_association *,
689 struct sock *);
690void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
691 union sctp_addr *);
692const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
693
694/* This is a structure for holding either an IPv6 or an IPv4 address. */
695/* sin_family -- AF_INET or AF_INET6
696 * sin_port -- ordinary port number
697 * sin_addr -- cast to either (struct in_addr) or (struct in6_addr)
698 */
699struct sctp_sockaddr_entry {
700 struct list_head list;
701 union sctp_addr a;
702};
703
704typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *);
705
706/* This structure holds lists of chunks as we are assembling for
707 * transmission.
708 */
709struct sctp_packet {
710 /* These are the SCTP header values (host order) for the packet. */
711 __u16 source_port;
712 __u16 destination_port;
713 __u32 vtag;
714
715 /* This contains the payload chunks. */
716 struct sk_buff_head chunks;
717
718 /* This is the overhead of the sctp and ip headers. */
719 size_t overhead;
720 /* This is the total size of all chunks INCLUDING padding. */
721 size_t size;
722
723 /* The packet is destined for this transport address.
724 * The function we finally use to pass down to the next lower
725 * layer lives in the transport structure.
726 */
727 struct sctp_transport *transport;
728
729 /* This packet contains a COOKIE-ECHO chunk. */
730 char has_cookie_echo;
731
732 /* This packet containsa SACK chunk. */
733 char has_sack;
734
735 /* SCTP cannot fragment this packet. So let ip fragment it. */
736 char ipfragok;
737
738 int malloced;
739};
740
741struct sctp_packet *sctp_packet_init(struct sctp_packet *,
742 struct sctp_transport *,
743 __u16 sport, __u16 dport);
744struct sctp_packet *sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
745sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *,
746 struct sctp_chunk *);
747sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *,
748 struct sctp_chunk *);
749int sctp_packet_transmit(struct sctp_packet *);
750void sctp_packet_free(struct sctp_packet *);
751
752static inline int sctp_packet_empty(struct sctp_packet *packet)
753{
754 return (packet->size == packet->overhead);
755}
756
757/* This represents a remote transport address.
758 * For local transport addresses, we just use union sctp_addr.
759 *
760 * RFC2960 Section 1.4 Key Terms
761 *
762 * o Transport address: A Transport Address is traditionally defined
763 * by Network Layer address, Transport Layer protocol and Transport
764 * Layer port number. In the case of SCTP running over IP, a
765 * transport address is defined by the combination of an IP address
766 * and an SCTP port number (where SCTP is the Transport protocol).
767 *
768 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
769 *
770 * o The sender keeps a separate congestion control parameter set for
771 * each of the destination addresses it can send to (not each
772 * source-destination pair but for each destination). The parameters
773 * should decay if the address is not used for a long enough time
774 * period.
775 *
776 */
777struct sctp_transport {
778 /* A list of transports. */
779 struct list_head transports;
780
781 /* Reference counting. */
782 atomic_t refcnt;
783 int dead;
784
785 /* This is the peer's IP address and port. */
786 union sctp_addr ipaddr;
787
788 /* These are the functions we call to handle LLP stuff. */
789 struct sctp_af *af_specific;
790
791 /* Which association do we belong to? */
792 struct sctp_association *asoc;
793
794 /* RFC2960
795 *
796 * 12.3 Per Transport Address Data
797 *
798 * For each destination transport address in the peer's
799 * address list derived from the INIT or INIT ACK chunk, a
800 * number of data elements needs to be maintained including:
801 */
802 __u32 rtt; /* This is the most recent RTT. */
803
804 /* RTO : The current retransmission timeout value. */
805 __u32 rto;
806
807 /* RTTVAR : The current RTT variation. */
808 __u32 rttvar;
809
810 /* SRTT : The current smoothed round trip time. */
811 __u32 srtt;
812
813 /* RTO-Pending : A flag used to track if one of the DATA
814 * chunks sent to this address is currently being
815 * used to compute a RTT. If this flag is 0,
816 * the next DATA chunk sent to this destination
817 * should be used to compute a RTT and this flag
818 * should be set. Every time the RTT
819 * calculation completes (i.e. the DATA chunk
820 * is SACK'd) clear this flag.
821 */
822 int rto_pending;
823
824 /*
825 * These are the congestion stats.
826 */
827 /* cwnd : The current congestion window. */
828 __u32 cwnd; /* This is the actual cwnd. */
829
830 /* ssthresh : The current slow start threshold value. */
831 __u32 ssthresh;
832
833 /* partial : The tracking method for increase of cwnd when in
834 * bytes acked : congestion avoidance mode (see Section 6.2.2)
835 */
836 __u32 partial_bytes_acked;
837
838 /* Data that has been sent, but not acknowledged. */
839 __u32 flight_size;
840
841 /* PMTU : The current known path MTU. */
842 __u32 pmtu;
843
844 /* Destination */
845 struct dst_entry *dst;
846 /* Source address. */
847 union sctp_addr saddr;
848
849 /* When was the last time(in jiffies) that a data packet was sent on
850 * this transport? This is used to adjust the cwnd when the transport
851 * becomes inactive.
852 */
853 unsigned long last_time_used;
854
855 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
856 * the destination address every heartbeat interval.
857 */
858 int hb_interval;
859
860 /* When was the last time (in jiffies) that we heard from this
861 * transport? We use this to pick new active and retran paths.
862 */
863 unsigned long last_time_heard;
864
865 /* Last time(in jiffies) when cwnd is reduced due to the congestion
866 * indication based on ECNE chunk.
867 */
868 unsigned long last_time_ecne_reduced;
869
870 /* active : The current active state of this destination,
871 * : i.e. DOWN, UP, etc.
872 */
873 int active;
874
875 /* hb_allowed : The current heartbeat state of this destination,
876 * : i.e. ALLOW-HB, NO-HEARTBEAT, etc.
877 */
878 int hb_allowed;
879
880 /* These are the error stats for this destination. */
881
882 /* Error count : The current error count for this destination. */
883 unsigned short error_count;
884
885 /* This is the max_retrans value for the transport and will
886 * be initialized to proto.max_retrans.path. This can be changed
887 * using SCTP_SET_PEER_ADDR_PARAMS socket option.
888 */
889 int max_retrans;
890
891 /* Per : A timer used by each destination.
892 * Destination :
893 * Timer :
894 *
895 * [Everywhere else in the text this is called T3-rtx. -ed]
896 */
897 struct timer_list T3_rtx_timer;
898
899 /* Heartbeat timer is per destination. */
900 struct timer_list hb_timer;
901
902 /* Since we're using per-destination retransmission timers
903 * (see above), we're also using per-destination "transmitted"
904 * queues. This probably ought to be a private struct
905 * accessible only within the outqueue, but it's not, yet.
906 */
907 struct list_head transmitted;
908
909 /* We build bundle-able packets for this transport here. */
910 struct sctp_packet packet;
911
912 /* This is the list of transports that have chunks to send. */
913 struct list_head send_ready;
914
915 int malloced; /* Is this structure kfree()able? */
916
917 /* State information saved for SFR_CACC algorithm. The key
918 * idea in SFR_CACC is to maintain state at the sender on a
919 * per-destination basis when a changeover happens.
920 * char changeover_active;
921 * char cycling_changeover;
922 * __u32 next_tsn_at_change;
923 * char cacc_saw_newack;
924 */
925 struct {
926 /* An unsigned integer, which stores the next TSN to be
927 * used by the sender, at the moment of changeover.
928 */
929 __u32 next_tsn_at_change;
930
931 /* A flag which indicates the occurrence of a changeover */
932 char changeover_active;
933
934 /* A flag which indicates whether the change of primary is
935 * the first switch to this destination address during an
936 * active switch.
937 */
938 char cycling_changeover;
939
940 /* A temporary flag, which is used during the processing of
941 * a SACK to estimate the causative TSN(s)'s group.
942 */
943 char cacc_saw_newack;
944 } cacc;
945};
946
947struct sctp_transport *sctp_transport_new(const union sctp_addr *, int);
948void sctp_transport_set_owner(struct sctp_transport *,
949 struct sctp_association *);
950void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
951 struct sctp_sock *);
952void sctp_transport_pmtu(struct sctp_transport *);
953void sctp_transport_free(struct sctp_transport *);
954void sctp_transport_reset_timers(struct sctp_transport *);
955void sctp_transport_hold(struct sctp_transport *);
956void sctp_transport_put(struct sctp_transport *);
957void sctp_transport_update_rto(struct sctp_transport *, __u32);
958void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
959void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t);
960unsigned long sctp_transport_timeout(struct sctp_transport *);
961
962
963/* This is the structure we use to queue packets as they come into
964 * SCTP. We write packets to it and read chunks from it.
965 */
966struct sctp_inq {
967 /* This is actually a queue of sctp_chunk each
968 * containing a partially decoded packet.
969 */
970 struct sk_buff_head in;
971 /* This is the packet which is currently off the in queue and is
972 * being worked on through the inbound chunk processing.
973 */
974 struct sctp_chunk *in_progress;
975
976 /* This is the delayed task to finish delivering inbound
977 * messages.
978 */
979 struct work_struct immediate;
980
981 int malloced; /* Is this structure kfree()able? */
982};
983
984void sctp_inq_init(struct sctp_inq *);
985void sctp_inq_free(struct sctp_inq *);
986void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
987struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
988void sctp_inq_set_th_handler(struct sctp_inq *, void (*)(void *), void *);
989
990/* This is the structure we use to hold outbound chunks. You push
991 * chunks in and they automatically pop out the other end as bundled
992 * packets (it calls (*output_handler)()).
993 *
994 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
995 * and 8.2 of the v13 draft.
996 *
997 * It handles retransmissions. The connection to the timeout portion
998 * of the state machine is through sctp_..._timeout() and timeout_handler.
999 *
1000 * If you feed it SACKs, it will eat them.
1001 *
1002 * If you give it big chunks, it will fragment them.
1003 *
1004 * It assigns TSN's to data chunks. This happens at the last possible
1005 * instant before transmission.
1006 *
1007 * When free()'d, it empties itself out via output_handler().
1008 */
1009struct sctp_outq {
1010 struct sctp_association *asoc;
1011
1012 /* Data pending that has never been transmitted. */
1013 struct sk_buff_head out;
1014
1015 unsigned out_qlen; /* Total length of queued data chunks. */
1016
1017 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1018 unsigned error;
1019
1020 /* These are control chunks we want to send. */
1021 struct sk_buff_head control;
1022
1023 /* These are chunks that have been sacked but are above the
1024 * CTSN, or cumulative tsn ack point.
1025 */
1026 struct list_head sacked;
1027
1028 /* Put chunks on this list to schedule them for
1029 * retransmission.
1030 */
1031 struct list_head retransmit;
1032
1033 /* Put chunks on this list to save them for FWD TSN processing as
1034 * they were abandoned.
1035 */
1036 struct list_head abandoned;
1037
1038 /* How many unackd bytes do we have in-flight? */
1039 __u32 outstanding_bytes;
1040
1041 /* Corked? */
1042 char cork;
1043
1044 /* Is this structure empty? */
1045 char empty;
1046
1047 /* Are we kfree()able? */
1048 char malloced;
1049};
1050
1051void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1052void sctp_outq_teardown(struct sctp_outq *);
1053void sctp_outq_free(struct sctp_outq*);
1054int sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk);
1055int sctp_outq_flush(struct sctp_outq *, int);
1056int sctp_outq_sack(struct sctp_outq *, struct sctp_sackhdr *);
1057int sctp_outq_is_empty(const struct sctp_outq *);
1058void sctp_outq_restart(struct sctp_outq *);
1059
1060void sctp_retransmit(struct sctp_outq *, struct sctp_transport *,
1061 sctp_retransmit_reason_t);
1062void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1063int sctp_outq_uncork(struct sctp_outq *);
1064/* Uncork and flush an outqueue. */
1065static inline void sctp_outq_cork(struct sctp_outq *q)
1066{
1067 q->cork = 1;
1068}
1069
1070/* These bind address data fields common between endpoints and associations */
1071struct sctp_bind_addr {
1072
1073 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1074 *
1075 * SCTP Port: The local SCTP port number the endpoint is
1076 * bound to.
1077 */
1078 __u16 port;
1079
1080 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1081 *
1082 * Address List: The list of IP addresses that this instance
1083 * has bound. This information is passed to one's
1084 * peer(s) in INIT and INIT ACK chunks.
1085 */
1086 struct list_head address_list;
1087
1088 int malloced; /* Are we kfree()able? */
1089};
1090
1091void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1092void sctp_bind_addr_free(struct sctp_bind_addr *);
1093int sctp_bind_addr_copy(struct sctp_bind_addr *dest,
1094 const struct sctp_bind_addr *src,
1095 sctp_scope_t scope, int gfp,int flags);
1096int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1097 int gfp);
1098int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1099int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1100 struct sctp_sock *);
1101union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp,
1102 const union sctp_addr *addrs,
1103 int addrcnt,
1104 struct sctp_sock *opt);
1105union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1106 int *addrs_len, int gfp);
1107int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1108 __u16 port, int gfp);
1109
1110sctp_scope_t sctp_scope(const union sctp_addr *);
1111int sctp_in_scope(const union sctp_addr *addr, const sctp_scope_t scope);
1112int sctp_is_any(const union sctp_addr *addr);
1113int sctp_addr_is_valid(const union sctp_addr *addr);
1114
1115
1116/* What type of endpoint? */
1117typedef enum {
1118 SCTP_EP_TYPE_SOCKET,
1119 SCTP_EP_TYPE_ASSOCIATION,
1120} sctp_endpoint_type_t;
1121
1122/*
1123 * A common base class to bridge the implmentation view of a
1124 * socket (usually listening) endpoint versus an association's
1125 * local endpoint.
1126 * This common structure is useful for several purposes:
1127 * 1) Common interface for lookup routines.
1128 * a) Subfunctions work for either endpoint or association
1129 * b) Single interface to lookup allows hiding the lookup lock rather
1130 * than acquiring it externally.
1131 * 2) Common interface for the inbound chunk handling/state machine.
1132 * 3) Common object handling routines for reference counting, etc.
1133 * 4) Disentangle association lookup from endpoint lookup, where we
1134 * do not have to find our endpoint to find our association.
1135 *
1136 */
1137
1138struct sctp_ep_common {
1139 /* Fields to help us manage our entries in the hash tables. */
1140 struct sctp_ep_common *next;
1141 struct sctp_ep_common **pprev;
1142 int hashent;
1143
1144 /* Runtime type information. What kind of endpoint is this? */
1145 sctp_endpoint_type_t type;
1146
1147 /* Some fields to help us manage this object.
1148 * refcnt - Reference count access to this object.
1149 * dead - Do not attempt to use this object.
1150 * malloced - Do we need to kfree this object?
1151 */
1152 atomic_t refcnt;
1153 char dead;
1154 char malloced;
1155
1156 /* What socket does this endpoint belong to? */
1157 struct sock *sk;
1158
1159 /* This is where we receive inbound chunks. */
1160 struct sctp_inq inqueue;
1161
1162 /* This substructure includes the defining parameters of the
1163 * endpoint:
1164 * bind_addr.port is our shared port number.
1165 * bind_addr.address_list is our set of local IP addresses.
1166 */
1167 struct sctp_bind_addr bind_addr;
1168
1169 /* Protection during address list comparisons. */
1170 rwlock_t addr_lock;
1171};
1172
1173
1174/* RFC Section 1.4 Key Terms
1175 *
1176 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1177 * multi-homed host, an SCTP endpoint is represented to its peers as a
1178 * combination of a set of eligible destination transport addresses to
1179 * which SCTP packets can be sent and a set of eligible source
1180 * transport addresses from which SCTP packets can be received.
1181 * All transport addresses used by an SCTP endpoint must use the
1182 * same port number, but can use multiple IP addresses. A transport
1183 * address used by an SCTP endpoint must not be used by another
1184 * SCTP endpoint. In other words, a transport address is unique
1185 * to an SCTP endpoint.
1186 *
1187 * From an implementation perspective, each socket has one of these.
1188 * A TCP-style socket will have exactly one association on one of
1189 * these. An UDP-style socket will have multiple associations hanging
1190 * off one of these.
1191 */
1192
1193struct sctp_endpoint {
1194 /* Common substructure for endpoint and association. */
1195 struct sctp_ep_common base;
1196
1197 /* Associations: A list of current associations and mappings
1198 * to the data consumers for each association. This
1199 * may be in the form of a hash table or other
1200 * implementation dependent structure. The data
1201 * consumers may be process identification
1202 * information such as file descriptors, named pipe
1203 * pointer, or table pointers dependent on how SCTP
1204 * is implemented.
1205 */
1206 /* This is really a list of struct sctp_association entries. */
1207 struct list_head asocs;
1208
1209 /* Secret Key: A secret key used by this endpoint to compute
1210 * the MAC. This SHOULD be a cryptographic quality
1211 * random number with a sufficient length.
1212 * Discussion in [RFC1750] can be helpful in
1213 * selection of the key.
1214 */
1215 __u8 secret_key[SCTP_HOW_MANY_SECRETS][SCTP_SECRET_SIZE];
1216 int current_key;
1217 int last_key;
1218 int key_changed_at;
1219
1220 /* Default timeouts. */
1221 int timeouts[SCTP_NUM_TIMEOUT_TYPES];
1222
Neil Horman4eb701d2005-04-28 12:02:04 -07001223 /* sendbuf acct. policy. */
1224 __u32 sndbuf_policy;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001225
1226 /* Name for debugging output... */
1227 char *debug_name;
1228};
1229
1230/* Recover the outter endpoint structure. */
1231static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1232{
1233 struct sctp_endpoint *ep;
1234
1235 ep = container_of(base, struct sctp_endpoint, base);
1236 return ep;
1237}
1238
1239/* These are function signatures for manipulating endpoints. */
1240struct sctp_endpoint *sctp_endpoint_new(struct sock *, int);
1241void sctp_endpoint_free(struct sctp_endpoint *);
1242void sctp_endpoint_put(struct sctp_endpoint *);
1243void sctp_endpoint_hold(struct sctp_endpoint *);
1244void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1245struct sctp_association *sctp_endpoint_lookup_assoc(
1246 const struct sctp_endpoint *ep,
1247 const union sctp_addr *paddr,
1248 struct sctp_transport **);
1249int sctp_endpoint_is_peeled_off(struct sctp_endpoint *,
1250 const union sctp_addr *);
1251struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1252 const union sctp_addr *);
1253int sctp_has_association(const union sctp_addr *laddr,
1254 const union sctp_addr *paddr);
1255
1256int sctp_verify_init(const struct sctp_association *asoc, sctp_cid_t,
1257 sctp_init_chunk_t *peer_init, struct sctp_chunk *chunk,
1258 struct sctp_chunk **err_chunk);
1259int sctp_process_init(struct sctp_association *, sctp_cid_t cid,
1260 const union sctp_addr *peer,
1261 sctp_init_chunk_t *init, int gfp);
1262__u32 sctp_generate_tag(const struct sctp_endpoint *);
1263__u32 sctp_generate_tsn(const struct sctp_endpoint *);
1264
1265
1266/* RFC2960
1267 *
1268 * 12. Recommended Transmission Control Block (TCB) Parameters
1269 *
1270 * This section details a recommended set of parameters that should
1271 * be contained within the TCB for an implementation. This section is
1272 * for illustrative purposes and should not be deemed as requirements
1273 * on an implementation or as an exhaustive list of all parameters
1274 * inside an SCTP TCB. Each implementation may need its own additional
1275 * parameters for optimization.
1276 */
1277
1278
1279/* Here we have information about each individual association. */
1280struct sctp_association {
1281
1282 /* A base structure common to endpoint and association.
1283 * In this context, it represents the associations's view
1284 * of the local endpoint of the association.
1285 */
1286 struct sctp_ep_common base;
1287
1288 /* Associations on the same socket. */
1289 struct list_head asocs;
1290
1291 /* association id. */
1292 sctp_assoc_t assoc_id;
1293
1294 /* This is our parent endpoint. */
1295 struct sctp_endpoint *ep;
1296
1297 /* These are those association elements needed in the cookie. */
1298 struct sctp_cookie c;
1299
1300 /* This is all information about our peer. */
1301 struct {
1302 /* rwnd
1303 *
1304 * Peer Rwnd : Current calculated value of the peer's rwnd.
1305 */
1306 __u32 rwnd;
1307
1308 /* transport_addr_list
1309 *
1310 * Peer : A list of SCTP transport addresses that the
1311 * Transport : peer is bound to. This information is derived
1312 * Address : from the INIT or INIT ACK and is used to
1313 * List : associate an inbound packet with a given
1314 * : association. Normally this information is
1315 * : hashed or keyed for quick lookup and access
1316 * : of the TCB.
1317 *
1318 * It is a list of SCTP_transport's.
1319 */
1320 struct list_head transport_addr_list;
1321
1322 /* port
1323 * The transport layer port number.
1324 */
1325 __u16 port;
1326
1327 /* primary_path
1328 *
1329 * Primary : This is the current primary destination
1330 * Path : transport address of the peer endpoint. It
1331 * : may also specify a source transport address
1332 * : on this endpoint.
1333 *
1334 * All of these paths live on transport_addr_list.
1335 *
1336 * At the bakeoffs, we discovered that the intent of
1337 * primaryPath is that it only changes when the ULP
1338 * asks to have it changed. We add the activePath to
1339 * designate the connection we are currently using to
1340 * transmit new data and most control chunks.
1341 */
1342 struct sctp_transport *primary_path;
1343
1344 /* Cache the primary path address here, when we
1345 * need a an address for msg_name.
1346 */
1347 union sctp_addr primary_addr;
1348
1349 /* active_path
1350 * The path that we are currently using to
1351 * transmit new data and most control chunks.
1352 */
1353 struct sctp_transport *active_path;
1354
1355 /* retran_path
1356 *
1357 * RFC2960 6.4 Multi-homed SCTP Endpoints
1358 * ...
1359 * Furthermore, when its peer is multi-homed, an
1360 * endpoint SHOULD try to retransmit a chunk to an
1361 * active destination transport address that is
1362 * different from the last destination address to
1363 * which the DATA chunk was sent.
1364 */
1365 struct sctp_transport *retran_path;
1366
1367 /* Pointer to last transport I have sent on. */
1368 struct sctp_transport *last_sent_to;
1369
1370 /* This is the last transport I have received DATA on. */
1371 struct sctp_transport *last_data_from;
1372
1373 /*
1374 * Mapping An array of bits or bytes indicating which out of
1375 * Array order TSN's have been received (relative to the
1376 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1377 * order packets have been received, this array
1378 * will be set to all zero. This structure may be
1379 * in the form of a circular buffer or bit array.
1380 *
1381 * Last Rcvd : This is the last TSN received in
1382 * TSN : sequence. This value is set initially by
1383 * : taking the peer's Initial TSN, received in
1384 * : the INIT or INIT ACK chunk, and subtracting
1385 * : one from it.
1386 *
1387 * Throughout most of the specification this is called the
1388 * "Cumulative TSN ACK Point". In this case, we
1389 * ignore the advice in 12.2 in favour of the term
1390 * used in the bulk of the text. This value is hidden
1391 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1392 */
1393 struct sctp_tsnmap tsn_map;
1394 __u8 _map[sctp_tsnmap_storage_size(SCTP_TSN_MAP_SIZE)];
1395
1396 /* Ack State : This flag indicates if the next received
1397 * : packet is to be responded to with a
1398 * : SACK. This is initializedto 0. When a packet
1399 * : is received it is incremented. If this value
1400 * : reaches 2 or more, a SACK is sent and the
1401 * : value is reset to 0. Note: This is used only
1402 * : when no DATA chunks are received out of
1403 * : order. When DATA chunks are out of order,
1404 * : SACK's are not delayed (see Section 6).
1405 */
1406 __u8 sack_needed; /* Do we need to sack the peer? */
1407
1408 /* These are capabilities which our peer advertised. */
1409 __u8 ecn_capable; /* Can peer do ECN? */
1410 __u8 ipv4_address; /* Peer understands IPv4 addresses? */
1411 __u8 ipv6_address; /* Peer understands IPv6 addresses? */
1412 __u8 hostname_address;/* Peer understands DNS addresses? */
1413 __u8 asconf_capable; /* Does peer support ADDIP? */
1414 __u8 prsctp_capable; /* Can peer do PR-SCTP? */
1415
1416 __u32 adaption_ind; /* Adaption Code point. */
1417
1418 /* This mask is used to disable sending the ASCONF chunk
1419 * with specified parameter to peer.
1420 */
1421 __u16 addip_disabled_mask;
1422
1423 struct sctp_inithdr i;
1424 int cookie_len;
1425 void *cookie;
1426
1427 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1428 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1429 * Initial TSN Value minus 1
1430 */
1431 __u32 addip_serial;
1432 } peer;
1433
1434 /* State : A state variable indicating what state the
1435 * : association is in, i.e. COOKIE-WAIT,
1436 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1437 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1438 *
1439 * Note: No "CLOSED" state is illustrated since if a
1440 * association is "CLOSED" its TCB SHOULD be removed.
1441 *
1442 * In this implementation we DO have a CLOSED
1443 * state which is used during initiation and shutdown.
1444 *
1445 * State takes values from SCTP_STATE_*.
1446 */
1447 sctp_state_t state;
1448
1449 /* The cookie life I award for any cookie. */
1450 struct timeval cookie_life;
1451
1452 /* Overall : The overall association error count.
1453 * Error Count : [Clear this any time I get something.]
1454 */
1455 int overall_error_count;
1456
1457 /* These are the association's initial, max, and min RTO values.
1458 * These values will be initialized by system defaults, but can
1459 * be modified via the SCTP_RTOINFO socket option.
1460 */
1461 __u32 rto_initial;
1462 __u32 rto_max;
1463 __u32 rto_min;
1464
1465 /* Maximum number of new data packets that can be sent in a burst. */
1466 int max_burst;
1467
1468 /* This is the max_retrans value for the association. This value will
1469 * be initialized initialized from system defaults, but can be
1470 * modified by the SCTP_ASSOCINFO socket option.
1471 */
1472 int max_retrans;
1473
1474 /* Maximum number of times the endpoint will retransmit INIT */
1475 __u16 max_init_attempts;
1476
1477 /* How many times have we resent an INIT? */
1478 __u16 init_retries;
1479
1480 /* The largest timeout or RTO value to use in attempting an INIT */
1481 __u16 max_init_timeo;
1482
1483 int timeouts[SCTP_NUM_TIMEOUT_TYPES];
1484 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1485
1486 /* Transport to which SHUTDOWN chunk was last sent. */
1487 struct sctp_transport *shutdown_last_sent_to;
1488
1489 /* Next TSN : The next TSN number to be assigned to a new
1490 * : DATA chunk. This is sent in the INIT or INIT
1491 * : ACK chunk to the peer and incremented each
1492 * : time a DATA chunk is assigned a TSN
1493 * : (normally just prior to transmit or during
1494 * : fragmentation).
1495 */
1496 __u32 next_tsn;
1497
1498 /*
1499 * Last Rcvd : This is the last TSN received in sequence. This value
1500 * TSN : is set initially by taking the peer's Initial TSN,
1501 * : received in the INIT or INIT ACK chunk, and
1502 * : subtracting one from it.
1503 *
1504 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1505 */
1506
1507 __u32 ctsn_ack_point;
1508
1509 /* PR-SCTP Advanced.Peer.Ack.Point */
1510 __u32 adv_peer_ack_point;
1511
1512 /* Highest TSN that is acknowledged by incoming SACKs. */
1513 __u32 highest_sacked;
1514
1515 /* The number of unacknowledged data chunks. Reported through
1516 * the SCTP_STATUS sockopt.
1517 */
1518 __u16 unack_data;
1519
1520 /* This is the association's receive buffer space. This value is used
1521 * to set a_rwnd field in an INIT or a SACK chunk.
1522 */
1523 __u32 rwnd;
1524
1525 /* This is the last advertised value of rwnd over a SACK chunk. */
1526 __u32 a_rwnd;
1527
1528 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1529 * to slop over a maximum of the association's frag_point.
1530 */
1531 __u32 rwnd_over;
1532
1533 /* This is the sndbuf size in use for the association.
1534 * This corresponds to the sndbuf size for the association,
1535 * as specified in the sk->sndbuf.
1536 */
1537 int sndbuf_used;
1538
1539 /* This is the wait queue head for send requests waiting on
1540 * the association sndbuf space.
1541 */
1542 wait_queue_head_t wait;
1543
1544 /* Association : The smallest PMTU discovered for all of the
1545 * PMTU : peer's transport addresses.
1546 */
1547 __u32 pmtu;
1548
1549 /* The message size at which SCTP fragmentation will occur. */
1550 __u32 frag_point;
1551
1552 /* Currently only one counter is used to count INIT errors. */
1553 int counters[SCTP_NUMBER_COUNTERS];
1554
1555 /* Default send parameters. */
1556 __u16 default_stream;
1557 __u16 default_flags;
1558 __u32 default_ppid;
1559 __u32 default_context;
1560 __u32 default_timetolive;
1561
1562 /* This tracks outbound ssn for a given stream. */
1563 struct sctp_ssnmap *ssnmap;
1564
1565 /* All outbound chunks go through this structure. */
1566 struct sctp_outq outqueue;
1567
1568 /* A smart pipe that will handle reordering and fragmentation,
1569 * as well as handle passing events up to the ULP.
1570 */
1571 struct sctp_ulpq ulpq;
1572
1573 /* Last TSN that caused an ECNE Chunk to be sent. */
1574 __u32 last_ecne_tsn;
1575
1576 /* Last TSN that caused a CWR Chunk to be sent. */
1577 __u32 last_cwr_tsn;
1578
1579 /* How many duplicated TSNs have we seen? */
1580 int numduptsns;
1581
1582 /* Number of seconds of idle time before an association is closed. */
1583 __u32 autoclose;
1584
1585 /* These are to support
1586 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1587 * and Enforcement of Flow and Message Limits"
1588 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1589 * or "ADDIP" for short.
1590 */
1591
1592
1593
1594 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1595 *
1596 * R1) One and only one ASCONF Chunk MAY be in transit and
1597 * unacknowledged at any one time. If a sender, after sending
1598 * an ASCONF chunk, decides it needs to transfer another
1599 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1600 * returns from the previous ASCONF Chunk before sending a
1601 * subsequent ASCONF. Note this restriction binds each side,
1602 * so at any time two ASCONF may be in-transit on any given
1603 * association (one sent from each endpoint).
1604 *
1605 * [This is our one-and-only-one ASCONF in flight. If we do
1606 * not have an ASCONF in flight, this is NULL.]
1607 */
1608 struct sctp_chunk *addip_last_asconf;
1609
1610 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1611 *
1612 * IMPLEMENTATION NOTE: As an optimization a receiver may wish
1613 * to save the last ASCONF-ACK for some predetermined period
1614 * of time and instead of re-processing the ASCONF (with the
1615 * same serial number) it may just re-transmit the
1616 * ASCONF-ACK. It may wish to use the arrival of a new serial
1617 * number to discard the previously saved ASCONF-ACK or any
1618 * other means it may choose to expire the saved ASCONF-ACK.
1619 *
1620 * [This is our saved ASCONF-ACK. We invalidate it when a new
1621 * ASCONF serial number arrives.]
1622 */
1623 struct sctp_chunk *addip_last_asconf_ack;
1624
1625 /* These ASCONF chunks are waiting to be sent.
1626 *
1627 * These chunaks can't be pushed to outqueue until receiving
1628 * ASCONF_ACK for the previous ASCONF indicated by
1629 * addip_last_asconf, so as to guarantee that only one ASCONF
1630 * is in flight at any time.
1631 *
1632 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1633 *
1634 * In defining the ASCONF Chunk transfer procedures, it is
1635 * essential that these transfers MUST NOT cause congestion
1636 * within the network. To achieve this, we place these
1637 * restrictions on the transfer of ASCONF Chunks:
1638 *
1639 * R1) One and only one ASCONF Chunk MAY be in transit and
1640 * unacknowledged at any one time. If a sender, after sending
1641 * an ASCONF chunk, decides it needs to transfer another
1642 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1643 * returns from the previous ASCONF Chunk before sending a
1644 * subsequent ASCONF. Note this restriction binds each side,
1645 * so at any time two ASCONF may be in-transit on any given
1646 * association (one sent from each endpoint).
1647 *
1648 *
1649 * [I really think this is EXACTLY the sort of intelligence
1650 * which already resides in sctp_outq. Please move this
1651 * queue and its supporting logic down there. --piggy]
1652 */
1653 struct sk_buff_head addip_chunks;
1654
1655 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1656 *
1657 * A2) A serial number should be assigned to the Chunk. The
1658 * serial number SHOULD be a monotonically increasing
1659 * number. The serial number SHOULD be initialized at
1660 * the start of the association to the same value as the
1661 * Initial TSN and every time a new ASCONF chunk is created
1662 * it is incremented by one after assigning the serial number
1663 * to the newly created chunk.
1664 *
1665 * ADDIP
1666 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
1667 *
1668 * Serial Number : 32 bits (unsigned integer)
1669 *
1670 * This value represents a Serial Number for the ASCONF
1671 * Chunk. The valid range of Serial Number is from 0 to
1672 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
1673 * after reaching 4294967295.
1674 */
1675 __u32 addip_serial;
1676
1677 /* Need to send an ECNE Chunk? */
1678 char need_ecne;
1679
1680 /* Is it a temporary association? */
1681 char temp;
1682};
1683
1684
1685/* An eyecatcher for determining if we are really looking at an
1686 * association data structure.
1687 */
1688enum {
1689 SCTP_ASSOC_EYECATCHER = 0xa550c123,
1690};
1691
1692/* Recover the outter association structure. */
1693static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
1694{
1695 struct sctp_association *asoc;
1696
1697 asoc = container_of(base, struct sctp_association, base);
1698 return asoc;
1699}
1700
1701/* These are function signatures for manipulating associations. */
1702
1703
1704struct sctp_association *
1705sctp_association_new(const struct sctp_endpoint *, const struct sock *,
1706 sctp_scope_t scope, int gfp);
1707void sctp_association_free(struct sctp_association *);
1708void sctp_association_put(struct sctp_association *);
1709void sctp_association_hold(struct sctp_association *);
1710
1711struct sctp_transport *sctp_assoc_choose_shutdown_transport(
1712 struct sctp_association *);
1713void sctp_assoc_update_retran_path(struct sctp_association *);
1714struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
1715 const union sctp_addr *);
1716int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1717 const union sctp_addr *laddr);
1718struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
1719 const union sctp_addr *address,
1720 const int gfp);
1721void sctp_assoc_del_peer(struct sctp_association *asoc,
1722 const union sctp_addr *addr);
1723void sctp_assoc_control_transport(struct sctp_association *,
1724 struct sctp_transport *,
1725 sctp_transport_cmd_t, sctp_sn_error_t);
1726struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
1727struct sctp_transport *sctp_assoc_is_match(struct sctp_association *,
1728 const union sctp_addr *,
1729 const union sctp_addr *);
1730void sctp_assoc_migrate(struct sctp_association *, struct sock *);
1731void sctp_assoc_update(struct sctp_association *old,
1732 struct sctp_association *new);
1733
1734__u32 sctp_association_get_next_tsn(struct sctp_association *);
1735
1736void sctp_assoc_sync_pmtu(struct sctp_association *);
1737void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned);
1738void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned);
1739void sctp_assoc_set_primary(struct sctp_association *,
1740 struct sctp_transport *);
1741int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *, int);
1742int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
1743 struct sctp_cookie*, int gfp);
1744
1745int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1746 const union sctp_addr *ss2);
1747struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
1748
1749/* A convenience structure to parse out SCTP specific CMSGs. */
1750typedef struct sctp_cmsgs {
1751 struct sctp_initmsg *init;
1752 struct sctp_sndrcvinfo *info;
1753} sctp_cmsgs_t;
1754
1755/* Structure for tracking memory objects */
1756typedef struct {
1757 char *label;
1758 atomic_t *counter;
1759} sctp_dbg_objcnt_entry_t;
1760
1761#endif /* __sctp_structs_h__ */