1 /* SCTP kernel implementation
2 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999-2000 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 * Copyright (c) 2001 Intel Corp.
7 * This file is part of the SCTP kernel implementation
9 * This SCTP implementation is free software;
10 * you can redistribute it and/or modify it under the terms of
11 * the GNU General Public License as published by
12 * the Free Software Foundation; either version 2, or (at your option)
15 * This SCTP implementation is distributed in the hope that it
16 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
17 * ************************
18 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
19 * See the GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with GNU CC; see the file COPYING. If not, write to
23 * the Free Software Foundation, 59 Temple Place - Suite 330,
24 * Boston, MA 02111-1307, USA.
26 * Please send any bug reports or fixes you make to the
28 * lksctp developers <lksctp-developers@lists.sourceforge.net>
30 * Or submit a bug report through the following website:
31 * http://www.sf.net/projects/lksctp
33 * Written or modified by:
34 * Randall Stewart <randall@sctp.chicago.il.us>
35 * Ken Morneau <kmorneau@cisco.com>
36 * Qiaobing Xie <qxie1@email.mot.com>
37 * La Monte H.P. Yarroll <piggy@acm.org>
38 * Karl Knutson <karl@athena.chicago.il.us>
39 * Jon Grimm <jgrimm@us.ibm.com>
40 * Xingang Guo <xingang.guo@intel.com>
41 * Hui Huang <hui.huang@nokia.com>
42 * Sridhar Samudrala <sri@us.ibm.com>
43 * Daisy Chang <daisyc@us.ibm.com>
44 * Dajiang Zhang <dajiang.zhang@nokia.com>
45 * Ardelle Fan <ardelle.fan@intel.com>
46 * Ryan Layer <rmlayer@us.ibm.com>
47 * Anup Pemmaiah <pemmaiah@cc.usu.edu>
48 * Kevin Gao <kevin.gao@intel.com>
50 * Any bugs reported given to us we will try to fix... any fixes shared will
51 * be incorporated into the next SCTP release.
54 #ifndef __sctp_structs_h__
55 #define __sctp_structs_h__
57 #include <linux/time.h> /* We get struct timespec. */
58 #include <linux/socket.h> /* linux/in.h needs this!! */
59 #include <linux/in.h> /* We get struct sockaddr_in. */
60 #include <linux/in6.h> /* We get struct in6_addr */
61 #include <linux/ipv6.h>
62 #include <asm/param.h> /* We get MAXHOSTNAMELEN. */
63 #include <asm/atomic.h> /* This gets us atomic counters. */
64 #include <linux/skbuff.h> /* We need sk_buff_head. */
65 #include <linux/workqueue.h> /* We need tq_struct. */
66 #include <linux/sctp.h> /* We need sctp* header structs. */
67 #include <net/sctp/auth.h> /* We need auth specific structs */
69 /* A convenience structure for handling sockaddr structures.
70 * We should wean ourselves off this.
73 struct sockaddr_in v4;
74 struct sockaddr_in6 v6;
78 /* Forward declarations for data structures. */
81 struct sctp_association;
82 struct sctp_transport;
87 struct sctp_bind_addr;
89 struct sctp_ep_common;
94 #include <net/sctp/tsnmap.h>
95 #include <net/sctp/ulpevent.h>
96 #include <net/sctp/ulpqueue.h>
98 /* Structures useful for managing bind/connect. */
100 struct sctp_bind_bucket {
102 unsigned short fastreuse;
103 struct hlist_node node;
104 struct hlist_head owner;
107 struct sctp_bind_hashbucket {
109 struct hlist_head chain;
112 /* Used for hashing all associations. */
113 struct sctp_hashbucket {
115 struct hlist_head chain;
116 } __attribute__((__aligned__(8)));
119 /* The SCTP globals structure. */
120 extern struct sctp_globals {
121 /* RFC2960 Section 14. Suggested SCTP Protocol Parameter Values
123 * The following protocol parameters are RECOMMENDED:
125 * RTO.Initial - 3 seconds
127 * RTO.Max - 60 seconds
128 * RTO.Alpha - 1/8 (3 when converted to right shifts.)
129 * RTO.Beta - 1/4 (2 when converted to right shifts.)
131 unsigned int rto_initial;
132 unsigned int rto_min;
133 unsigned int rto_max;
135 /* Note: rto_alpha and rto_beta are really defined as inverse
136 * powers of two to facilitate integer operations.
144 /* Whether Cookie Preservative is enabled(1) or not(0) */
145 int cookie_preserve_enable;
147 /* Valid.Cookie.Life - 60 seconds */
148 unsigned int valid_cookie_life;
150 /* Delayed SACK timeout 200ms default*/
151 unsigned int sack_timeout;
153 /* HB.interval - 30 seconds */
154 unsigned int hb_interval;
156 /* Association.Max.Retrans - 10 attempts
157 * Path.Max.Retrans - 5 attempts (per destination address)
158 * Max.Init.Retransmits - 8 attempts
160 int max_retrans_association;
161 int max_retrans_path;
162 int max_retrans_init;
165 * Policy for preforming sctp/socket accounting
166 * 0 - do socket level accounting, all assocs share sk_sndbuf
167 * 1 - do sctp accounting, each asoc may use sk_sndbuf bytes
172 * Policy for preforming sctp/socket accounting
173 * 0 - do socket level accounting, all assocs share sk_rcvbuf
174 * 1 - do sctp accounting, each asoc may use sk_rcvbuf bytes
178 /* The following variables are implementation specific. */
180 /* Default initialization values to be applied to new associations. */
182 __u16 max_outstreams;
184 /* This is a list of groups of functions for each address
185 * family that we support.
187 struct list_head address_families;
189 /* This is the hash of all endpoints. */
191 struct sctp_hashbucket *ep_hashtable;
193 /* This is the hash of all associations. */
195 struct sctp_hashbucket *assoc_hashtable;
197 /* This is the sctp port control hash. */
199 struct sctp_bind_hashbucket *port_hashtable;
201 /* This is the global local address list.
202 * We actively maintain this complete list of addresses on
203 * the system by catching address add/delete events.
205 * It is a list of sctp_sockaddr_entry.
207 struct list_head local_addr_list;
209 /* Lock that protects the local_addr_list writers */
210 spinlock_t addr_list_lock;
212 /* Flag to indicate if addip is enabled. */
214 int addip_noauth_enable;
216 /* Flag to indicate if PR-SCTP is enabled. */
219 /* Flag to idicate if SCTP-AUTH is enabled */
223 * Policy to control SCTP IPv4 address scoping
224 * 0 - Disable IPv4 address scoping
225 * 1 - Enable IPv4 address scoping
226 * 2 - Selectively allow only IPv4 private addresses
227 * 3 - Selectively allow only IPv4 link local address
229 int ipv4_scope_policy;
231 /* Flag to indicate whether computing and verifying checksum
233 int checksum_disable;
235 /* Threshold for rwnd update SACKS. Receive buffer shifted this many
236 * bits is an indicator of when to send and window update SACK.
238 int rwnd_update_shift;
241 #define sctp_rto_initial (sctp_globals.rto_initial)
242 #define sctp_rto_min (sctp_globals.rto_min)
243 #define sctp_rto_max (sctp_globals.rto_max)
244 #define sctp_rto_alpha (sctp_globals.rto_alpha)
245 #define sctp_rto_beta (sctp_globals.rto_beta)
246 #define sctp_max_burst (sctp_globals.max_burst)
247 #define sctp_valid_cookie_life (sctp_globals.valid_cookie_life)
248 #define sctp_cookie_preserve_enable (sctp_globals.cookie_preserve_enable)
249 #define sctp_max_retrans_association (sctp_globals.max_retrans_association)
250 #define sctp_sndbuf_policy (sctp_globals.sndbuf_policy)
251 #define sctp_rcvbuf_policy (sctp_globals.rcvbuf_policy)
252 #define sctp_max_retrans_path (sctp_globals.max_retrans_path)
253 #define sctp_max_retrans_init (sctp_globals.max_retrans_init)
254 #define sctp_sack_timeout (sctp_globals.sack_timeout)
255 #define sctp_hb_interval (sctp_globals.hb_interval)
256 #define sctp_max_instreams (sctp_globals.max_instreams)
257 #define sctp_max_outstreams (sctp_globals.max_outstreams)
258 #define sctp_address_families (sctp_globals.address_families)
259 #define sctp_ep_hashsize (sctp_globals.ep_hashsize)
260 #define sctp_ep_hashtable (sctp_globals.ep_hashtable)
261 #define sctp_assoc_hashsize (sctp_globals.assoc_hashsize)
262 #define sctp_assoc_hashtable (sctp_globals.assoc_hashtable)
263 #define sctp_port_hashsize (sctp_globals.port_hashsize)
264 #define sctp_port_rover (sctp_globals.port_rover)
265 #define sctp_port_alloc_lock (sctp_globals.port_alloc_lock)
266 #define sctp_port_hashtable (sctp_globals.port_hashtable)
267 #define sctp_local_addr_list (sctp_globals.local_addr_list)
268 #define sctp_local_addr_lock (sctp_globals.addr_list_lock)
269 #define sctp_scope_policy (sctp_globals.ipv4_scope_policy)
270 #define sctp_addip_enable (sctp_globals.addip_enable)
271 #define sctp_addip_noauth (sctp_globals.addip_noauth_enable)
272 #define sctp_prsctp_enable (sctp_globals.prsctp_enable)
273 #define sctp_auth_enable (sctp_globals.auth_enable)
274 #define sctp_checksum_disable (sctp_globals.checksum_disable)
275 #define sctp_rwnd_upd_shift (sctp_globals.rwnd_update_shift)
277 /* SCTP Socket type: UDP or TCP style. */
280 SCTP_SOCKET_UDP_HIGH_BANDWIDTH,
282 } sctp_socket_type_t;
284 /* Per socket SCTP information. */
286 /* inet_sock has to be the first member of sctp_sock */
287 struct inet_sock inet;
288 /* What kind of a socket is this? */
289 sctp_socket_type_t type;
291 /* PF_ family specific functions. */
294 /* Access to HMAC transform. */
295 struct crypto_hash *hmac;
297 /* What is our base endpointer? */
298 struct sctp_endpoint *ep;
300 struct sctp_bind_bucket *bind_hash;
301 /* Various Socket Options. */
302 __u16 default_stream;
305 __u32 default_context;
306 __u32 default_timetolive;
307 __u32 default_rcv_context;
310 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
311 * the destination address every heartbeat interval. This value
312 * will be inherited by all new associations.
316 /* This is the max_retrans value for new associations. */
319 /* The initial Path MTU to use for new associations. */
322 /* The default SACK delay timeout for new associations. */
326 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
329 struct sctp_initmsg initmsg;
330 struct sctp_rtoinfo rtoinfo;
331 struct sctp_paddrparams paddrparam;
332 struct sctp_event_subscribe subscribe;
333 struct sctp_assocparams assocparams;
337 __u8 disable_fragments;
339 __u8 frag_interleave;
340 __u32 adaptation_ind;
344 /* Receive to here while partial delivery is in effect. */
345 struct sk_buff_head pd_lobby;
348 static inline struct sctp_sock *sctp_sk(const struct sock *sk)
350 return (struct sctp_sock *)sk;
353 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
355 return (struct sock *)sp;
358 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
360 struct sctp_sock sctp;
361 struct ipv6_pinfo inet6;
363 #endif /* CONFIG_IPV6 */
366 /* This is our APPLICATION-SPECIFIC state cookie.
367 * THIS IS NOT DICTATED BY THE SPECIFICATION.
369 /* These are the parts of an association which we send in the cookie.
370 * Most of these are straight out of:
371 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
377 /* My : Tag expected in every inbound packet and sent
378 * Verification: in the INIT or INIT ACK chunk.
383 /* Peer's : Tag expected in every outbound packet except
384 * Verification: in the INIT chunk.
389 /* The rest of these are not from the spec, but really need to
393 /* My Tie Tag : Assist in discovering a restarting association. */
396 /* Peer's Tie Tag: Assist in discovering a restarting association. */
399 /* When does this cookie expire? */
400 struct timeval expiration;
402 /* Number of inbound/outbound streams which are set
403 * and negotiated during the INIT process.
405 __u16 sinit_num_ostreams;
406 __u16 sinit_max_instreams;
408 /* This is the first sequence number I used. */
411 /* This holds the originating address of the INIT packet. */
412 union sctp_addr peer_addr;
415 * Include the source port of the INIT-ACK
421 /* Padding for future use */
424 __u32 adaptation_ind;
426 __u8 auth_random[sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH];
427 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS + 2];
428 __u8 auth_chunks[sizeof(sctp_paramhdr_t) + SCTP_AUTH_MAX_CHUNKS];
430 /* This is a shim for my peer's INIT packet, followed by
431 * a copy of the raw address list of the association.
432 * The length of the raw address list is saved in the
433 * raw_addr_list_len field, which will be used at the time when
434 * the association TCB is re-constructed from the cookie.
436 __u32 raw_addr_list_len;
437 struct sctp_init_chunk peer_init[0];
441 /* The format of our cookie that we send to our peer. */
442 struct sctp_signed_cookie {
443 __u8 signature[SCTP_SECRET_SIZE];
444 __u32 __pad; /* force sctp_cookie alignment to 64 bits */
445 struct sctp_cookie c;
446 } __attribute__((packed));
448 /* This is another convenience type to allocate memory for address
449 * params for the maximum size and pass such structures around
452 union sctp_addr_param {
453 struct sctp_paramhdr p;
454 struct sctp_ipv4addr_param v4;
455 struct sctp_ipv6addr_param v6;
458 /* A convenience type to allow walking through the various
459 * parameters and avoid casting all over the place.
463 struct sctp_paramhdr *p;
464 struct sctp_cookie_preserve_param *life;
465 struct sctp_hostname_param *dns;
466 struct sctp_cookie_param *cookie;
467 struct sctp_supported_addrs_param *sat;
468 struct sctp_ipv4addr_param *v4;
469 struct sctp_ipv6addr_param *v6;
470 union sctp_addr_param *addr;
471 struct sctp_adaptation_ind_param *aind;
472 struct sctp_supported_ext_param *ext;
473 struct sctp_random_param *random;
474 struct sctp_chunks_param *chunks;
475 struct sctp_hmac_algo_param *hmac_algo;
476 struct sctp_addip_param *addip;
479 /* RFC 2960. Section 3.3.5 Heartbeat.
480 * Heartbeat Information: variable length
481 * The Sender-specific Heartbeat Info field should normally include
482 * information about the sender's current time when this HEARTBEAT
483 * chunk is sent and the destination transport address to which this
484 * HEARTBEAT is sent (see Section 8.3).
486 typedef struct sctp_sender_hb_info {
487 struct sctp_paramhdr param_hdr;
488 union sctp_addr daddr;
489 unsigned long sent_at;
491 } __attribute__((packed)) sctp_sender_hb_info_t;
494 * RFC 2960 1.3.2 Sequenced Delivery within Streams
496 * The term "stream" is used in SCTP to refer to a sequence of user
497 * messages that are to be delivered to the upper-layer protocol in
498 * order with respect to other messages within the same stream. This is
499 * in contrast to its usage in TCP, where it refers to a sequence of
500 * bytes (in this document a byte is assumed to be eight bits).
503 * This is the structure we use to track both our outbound and inbound
504 * SSN, or Stream Sequence Numbers.
513 struct sctp_stream in;
514 struct sctp_stream out;
518 struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out,
520 void sctp_ssnmap_free(struct sctp_ssnmap *map);
521 void sctp_ssnmap_clear(struct sctp_ssnmap *map);
523 /* What is the current SSN number for this stream? */
524 static inline __u16 sctp_ssn_peek(struct sctp_stream *stream, __u16 id)
526 return stream->ssn[id];
529 /* Return the next SSN number for this stream. */
530 static inline __u16 sctp_ssn_next(struct sctp_stream *stream, __u16 id)
532 return stream->ssn[id]++;
535 /* Skip over this ssn and all below. */
536 static inline void sctp_ssn_skip(struct sctp_stream *stream, __u16 id,
539 stream->ssn[id] = ssn+1;
543 * Pointers to address related SCTP functions.
544 * (i.e. things that depend on the address family.)
547 int (*sctp_xmit) (struct sk_buff *skb,
548 struct sctp_transport *);
549 int (*setsockopt) (struct sock *sk,
553 unsigned int optlen);
554 int (*getsockopt) (struct sock *sk,
559 int (*compat_setsockopt) (struct sock *sk,
563 unsigned int optlen);
564 int (*compat_getsockopt) (struct sock *sk,
569 struct dst_entry *(*get_dst) (struct sctp_association *asoc,
570 union sctp_addr *daddr,
571 union sctp_addr *saddr);
572 void (*get_saddr) (struct sctp_sock *sk,
573 struct sctp_association *asoc,
574 struct dst_entry *dst,
575 union sctp_addr *daddr,
576 union sctp_addr *saddr);
577 void (*copy_addrlist) (struct list_head *,
578 struct net_device *);
579 void (*dst_saddr) (union sctp_addr *saddr,
580 struct dst_entry *dst,
582 int (*cmp_addr) (const union sctp_addr *addr1,
583 const union sctp_addr *addr2);
584 void (*addr_copy) (union sctp_addr *dst,
585 union sctp_addr *src);
586 void (*from_skb) (union sctp_addr *,
589 void (*from_sk) (union sctp_addr *,
591 void (*to_sk_saddr) (union sctp_addr *,
593 void (*to_sk_daddr) (union sctp_addr *,
595 void (*from_addr_param) (union sctp_addr *,
596 union sctp_addr_param *,
597 __be16 port, int iif);
598 int (*to_addr_param) (const union sctp_addr *,
599 union sctp_addr_param *);
600 int (*addr_valid) (union sctp_addr *,
602 const struct sk_buff *);
603 sctp_scope_t (*scope) (union sctp_addr *);
604 void (*inaddr_any) (union sctp_addr *, __be16);
605 int (*is_any) (const union sctp_addr *);
606 int (*available) (union sctp_addr *,
608 int (*skb_iif) (const struct sk_buff *sk);
609 int (*is_ce) (const struct sk_buff *sk);
610 void (*seq_dump_addr)(struct seq_file *seq,
611 union sctp_addr *addr);
612 void (*ecn_capable)(struct sock *sk);
613 __u16 net_header_len;
615 sa_family_t sa_family;
616 struct list_head list;
619 struct sctp_af *sctp_get_af_specific(sa_family_t);
620 int sctp_register_af(struct sctp_af *);
622 /* Protocol family functions. */
624 void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
625 void (*skb_msgname) (struct sk_buff *, char *, int *);
626 int (*af_supported) (sa_family_t, struct sctp_sock *);
627 int (*cmp_addr) (const union sctp_addr *,
628 const union sctp_addr *,
630 int (*bind_verify) (struct sctp_sock *, union sctp_addr *);
631 int (*send_verify) (struct sctp_sock *, union sctp_addr *);
632 int (*supported_addrs)(const struct sctp_sock *, __be16 *);
633 struct sock *(*create_accept_sk) (struct sock *sk,
634 struct sctp_association *asoc);
635 void (*addr_v4map) (struct sctp_sock *, union sctp_addr *);
640 /* Structure to track chunk fragments that have been acked, but peer
641 * fragments of the same message have not.
643 struct sctp_datamsg {
644 /* Chunks waiting to be submitted to lower layer. */
645 struct list_head chunks;
646 /* Chunks that have been transmitted. */
648 /* Reference counting. */
650 /* When is this message no longer interesting to the peer? */
651 unsigned long expires_at;
652 /* Did the messenge fail to send? */
655 /* Control whether chunks from this message can be abandoned. */
659 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
660 struct sctp_sndrcvinfo *,
661 struct msghdr *, int len);
662 void sctp_datamsg_free(struct sctp_datamsg *);
663 void sctp_datamsg_put(struct sctp_datamsg *);
664 void sctp_chunk_fail(struct sctp_chunk *, int error);
665 int sctp_chunk_abandoned(struct sctp_chunk *);
667 /* RFC2960 1.4 Key Terms
669 * o Chunk: A unit of information within an SCTP packet, consisting of
670 * a chunk header and chunk-specific content.
672 * As a matter of convenience, we remember the SCTP common header for
673 * each chunk as well as a few other header pointers...
676 struct list_head list;
680 /* This is our link to the per-transport transmitted list. */
681 struct list_head transmitted_list;
683 /* This field is used by chunks that hold fragmented data.
684 * For the first fragment this is the list that holds the rest of
685 * fragments. For the remaining fragments, this is the link to the
686 * frag_list maintained in the first fragment.
688 struct list_head frag_list;
690 /* This points to the sk_buff containing the actual data. */
693 /* These are the SCTP headers by reverse order in a packet.
694 * Note that some of these may happen more than once. In that
695 * case, we point at the "current" one, whatever that means
696 * for that level of header.
699 /* We point this at the FIRST TLV parameter to chunk_hdr. */
700 union sctp_params param_hdr;
703 struct sctp_datahdr *data_hdr;
704 struct sctp_inithdr *init_hdr;
705 struct sctp_sackhdr *sack_hdr;
706 struct sctp_heartbeathdr *hb_hdr;
707 struct sctp_sender_hb_info *hbs_hdr;
708 struct sctp_shutdownhdr *shutdown_hdr;
709 struct sctp_signed_cookie *cookie_hdr;
710 struct sctp_ecnehdr *ecne_hdr;
711 struct sctp_cwrhdr *ecn_cwr_hdr;
712 struct sctp_errhdr *err_hdr;
713 struct sctp_addiphdr *addip_hdr;
714 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
715 struct sctp_authhdr *auth_hdr;
720 struct sctp_chunkhdr *chunk_hdr;
721 struct sctphdr *sctp_hdr;
723 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
724 struct sctp_sndrcvinfo sinfo;
726 /* Which association does this belong to? */
727 struct sctp_association *asoc;
729 /* What endpoint received this chunk? */
730 struct sctp_ep_common *rcvr;
732 /* We fill this in if we are calculating RTT. */
733 unsigned long sent_at;
735 /* What is the origin IP address for this chunk? */
736 union sctp_addr source;
737 /* Destination address for this chunk. */
738 union sctp_addr dest;
740 /* For outbound message, track all fragments for SEND_FAILED. */
741 struct sctp_datamsg *msg;
743 /* For an inbound chunk, this tells us where it came from.
744 * For an outbound chunk, it tells us where we'd like it to
745 * go. It is NULL if we have no preference.
747 struct sctp_transport *transport;
749 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO
750 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
751 * spec violates the principle premis that all chunks are processed
754 struct sk_buff *auth_chunk;
756 #define SCTP_CAN_FRTX 0x0
757 #define SCTP_NEED_FRTX 0x1
758 #define SCTP_DONT_FRTX 0x2
759 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */
760 has_tsn:1, /* Does this chunk have a TSN yet? */
761 has_ssn:1, /* Does this chunk have a SSN yet? */
762 singleton:1, /* Only chunk in the packet? */
763 end_of_packet:1, /* Last chunk in the packet? */
764 ecn_ce_done:1, /* Have we processed the ECN CE bit? */
765 pdiscard:1, /* Discard the whole packet now? */
766 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */
767 data_accepted:1, /* At least 1 chunk accepted */
768 auth:1, /* IN: was auth'ed | OUT: needs auth */
769 has_asconf:1, /* IN: have seen an asconf before */
770 tsn_missing_report:2, /* Data chunk missing counter. */
771 fast_retransmit:2; /* Is this chunk fast retransmitted? */
774 void sctp_chunk_hold(struct sctp_chunk *);
775 void sctp_chunk_put(struct sctp_chunk *);
776 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
778 void sctp_chunk_free(struct sctp_chunk *);
779 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
780 struct sctp_chunk *sctp_chunkify(struct sk_buff *,
781 const struct sctp_association *,
783 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
785 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
788 SCTP_ADDR_NEW, /* new address added to assoc/ep */
789 SCTP_ADDR_SRC, /* address can be used as source */
790 SCTP_ADDR_DEL, /* address about to be deleted */
793 /* This is a structure for holding either an IPv6 or an IPv4 address. */
794 struct sctp_sockaddr_entry {
795 struct list_head list;
802 typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *);
804 /* This structure holds lists of chunks as we are assembling for
808 /* These are the SCTP header values (host order) for the packet. */
810 __u16 destination_port;
813 /* This contains the payload chunks. */
814 struct list_head chunk_list;
816 /* This is the overhead of the sctp and ip headers. */
818 /* This is the total size of all chunks INCLUDING padding. */
821 /* The packet is destined for this transport address.
822 * The function we finally use to pass down to the next lower
823 * layer lives in the transport structure.
825 struct sctp_transport *transport;
827 /* pointer to the auth chunk for this packet */
828 struct sctp_chunk *auth;
830 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */
831 has_sack:1, /* This packet contains a SACK chunk. */
832 has_auth:1, /* This packet contains an AUTH chunk */
833 has_data:1, /* This packet contains at least 1 DATA chunk */
834 ipfragok:1, /* So let ip fragment this packet */
835 malloced:1; /* Is it malloced? */
838 struct sctp_packet *sctp_packet_init(struct sctp_packet *,
839 struct sctp_transport *,
840 __u16 sport, __u16 dport);
841 struct sctp_packet *sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
842 sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *,
843 struct sctp_chunk *, int);
844 sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *,
845 struct sctp_chunk *);
846 int sctp_packet_transmit(struct sctp_packet *);
847 void sctp_packet_free(struct sctp_packet *);
849 static inline int sctp_packet_empty(struct sctp_packet *packet)
851 return (packet->size == packet->overhead);
854 /* This represents a remote transport address.
855 * For local transport addresses, we just use union sctp_addr.
857 * RFC2960 Section 1.4 Key Terms
859 * o Transport address: A Transport Address is traditionally defined
860 * by Network Layer address, Transport Layer protocol and Transport
861 * Layer port number. In the case of SCTP running over IP, a
862 * transport address is defined by the combination of an IP address
863 * and an SCTP port number (where SCTP is the Transport protocol).
865 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
867 * o The sender keeps a separate congestion control parameter set for
868 * each of the destination addresses it can send to (not each
869 * source-destination pair but for each destination). The parameters
870 * should decay if the address is not used for a long enough time
874 struct sctp_transport {
875 /* A list of transports. */
876 struct list_head transports;
878 /* Reference counting. */
882 /* This is the peer's IP address and port. */
883 union sctp_addr ipaddr;
885 /* These are the functions we call to handle LLP stuff. */
886 struct sctp_af *af_specific;
888 /* Which association do we belong to? */
889 struct sctp_association *asoc;
893 * 12.3 Per Transport Address Data
895 * For each destination transport address in the peer's
896 * address list derived from the INIT or INIT ACK chunk, a
897 * number of data elements needs to be maintained including:
899 /* RTO : The current retransmission timeout value. */
902 __u32 rtt; /* This is the most recent RTT. */
904 /* RTTVAR : The current RTT variation. */
907 /* SRTT : The current smoothed round trip time. */
910 /* RTO-Pending : A flag used to track if one of the DATA
911 * chunks sent to this address is currently being
912 * used to compute a RTT. If this flag is 0,
913 * the next DATA chunk sent to this destination
914 * should be used to compute a RTT and this flag
915 * should be set. Every time the RTT
916 * calculation completes (i.e. the DATA chunk
917 * is SACK'd) clear this flag.
918 * hb_sent : a flag that signals that we have a pending heartbeat.
923 /* Flag to track the current fast recovery state */
927 * These are the congestion stats.
929 /* cwnd : The current congestion window. */
930 __u32 cwnd; /* This is the actual cwnd. */
932 /* ssthresh : The current slow start threshold value. */
935 /* partial : The tracking method for increase of cwnd when in
936 * bytes acked : congestion avoidance mode (see Section 6.2.2)
938 __u32 partial_bytes_acked;
940 /* Data that has been sent, but not acknowledged. */
943 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */
945 /* TSN marking the fast recovery exit point */
946 __u32 fast_recovery_exit;
949 struct dst_entry *dst;
950 /* Source address. */
951 union sctp_addr saddr;
953 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
954 * the destination address every heartbeat interval.
956 unsigned long hbinterval;
958 /* SACK delay timeout */
959 unsigned long sackdelay;
962 /* When was the last time (in jiffies) that we heard from this
963 * transport? We use this to pick new active and retran paths.
965 unsigned long last_time_heard;
967 /* Last time(in jiffies) when cwnd is reduced due to the congestion
968 * indication based on ECNE chunk.
970 unsigned long last_time_ecne_reduced;
972 /* This is the max_retrans value for the transport and will
973 * be initialized from the assocs value. This can be changed
974 * using SCTP_SET_PEER_ADDR_PARAMS socket option.
978 /* is the Path MTU update pending on this tranport */
981 /* PMTU : The current known path MTU. */
984 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
987 /* The number of times INIT has been sent on this transport. */
990 /* state : The current state of this destination,
991 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
995 /* These are the error stats for this destination. */
997 /* Error count : The current error count for this destination. */
998 unsigned short error_count;
1000 /* Per : A timer used by each destination.
1004 * [Everywhere else in the text this is called T3-rtx. -ed]
1006 struct timer_list T3_rtx_timer;
1008 /* Heartbeat timer is per destination. */
1009 struct timer_list hb_timer;
1011 /* Since we're using per-destination retransmission timers
1012 * (see above), we're also using per-destination "transmitted"
1013 * queues. This probably ought to be a private struct
1014 * accessible only within the outqueue, but it's not, yet.
1016 struct list_head transmitted;
1018 /* We build bundle-able packets for this transport here. */
1019 struct sctp_packet packet;
1021 /* This is the list of transports that have chunks to send. */
1022 struct list_head send_ready;
1024 int malloced; /* Is this structure kfree()able? */
1026 /* State information saved for SFR_CACC algorithm. The key
1027 * idea in SFR_CACC is to maintain state at the sender on a
1028 * per-destination basis when a changeover happens.
1029 * char changeover_active;
1030 * char cycling_changeover;
1031 * __u32 next_tsn_at_change;
1032 * char cacc_saw_newack;
1035 /* An unsigned integer, which stores the next TSN to be
1036 * used by the sender, at the moment of changeover.
1038 __u32 next_tsn_at_change;
1040 /* A flag which indicates the occurrence of a changeover */
1041 char changeover_active;
1043 /* A flag which indicates whether the change of primary is
1044 * the first switch to this destination address during an
1047 char cycling_changeover;
1049 /* A temporary flag, which is used during the processing of
1050 * a SACK to estimate the causative TSN(s)'s group.
1052 char cacc_saw_newack;
1055 /* 64-bit random number sent with heartbeat. */
1059 struct sctp_transport *sctp_transport_new(const union sctp_addr *,
1061 void sctp_transport_set_owner(struct sctp_transport *,
1062 struct sctp_association *);
1063 void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
1064 struct sctp_sock *);
1065 void sctp_transport_pmtu(struct sctp_transport *);
1066 void sctp_transport_free(struct sctp_transport *);
1067 void sctp_transport_reset_timers(struct sctp_transport *);
1068 void sctp_transport_hold(struct sctp_transport *);
1069 void sctp_transport_put(struct sctp_transport *);
1070 void sctp_transport_update_rto(struct sctp_transport *, __u32);
1071 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
1072 void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t);
1073 void sctp_transport_burst_limited(struct sctp_transport *);
1074 void sctp_transport_burst_reset(struct sctp_transport *);
1075 unsigned long sctp_transport_timeout(struct sctp_transport *);
1076 void sctp_transport_reset(struct sctp_transport *);
1077 void sctp_transport_update_pmtu(struct sctp_transport *, u32);
1080 /* This is the structure we use to queue packets as they come into
1081 * SCTP. We write packets to it and read chunks from it.
1084 /* This is actually a queue of sctp_chunk each
1085 * containing a partially decoded packet.
1087 struct list_head in_chunk_list;
1088 /* This is the packet which is currently off the in queue and is
1089 * being worked on through the inbound chunk processing.
1091 struct sctp_chunk *in_progress;
1093 /* This is the delayed task to finish delivering inbound
1096 struct work_struct immediate;
1098 int malloced; /* Is this structure kfree()able? */
1101 void sctp_inq_init(struct sctp_inq *);
1102 void sctp_inq_free(struct sctp_inq *);
1103 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
1104 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
1105 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *);
1106 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t);
1108 /* This is the structure we use to hold outbound chunks. You push
1109 * chunks in and they automatically pop out the other end as bundled
1110 * packets (it calls (*output_handler)()).
1112 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1113 * and 8.2 of the v13 draft.
1115 * It handles retransmissions. The connection to the timeout portion
1116 * of the state machine is through sctp_..._timeout() and timeout_handler.
1118 * If you feed it SACKs, it will eat them.
1120 * If you give it big chunks, it will fragment them.
1122 * It assigns TSN's to data chunks. This happens at the last possible
1123 * instant before transmission.
1125 * When free()'d, it empties itself out via output_handler().
1128 struct sctp_association *asoc;
1130 /* Data pending that has never been transmitted. */
1131 struct list_head out_chunk_list;
1133 unsigned out_qlen; /* Total length of queued data chunks. */
1135 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1138 /* These are control chunks we want to send. */
1139 struct list_head control_chunk_list;
1141 /* These are chunks that have been sacked but are above the
1142 * CTSN, or cumulative tsn ack point.
1144 struct list_head sacked;
1146 /* Put chunks on this list to schedule them for
1149 struct list_head retransmit;
1151 /* Put chunks on this list to save them for FWD TSN processing as
1152 * they were abandoned.
1154 struct list_head abandoned;
1156 /* How many unackd bytes do we have in-flight? */
1157 __u32 outstanding_bytes;
1159 /* Are we doing fast-rtx on this queue */
1165 /* Is this structure empty? */
1168 /* Are we kfree()able? */
1172 void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1173 void sctp_outq_teardown(struct sctp_outq *);
1174 void sctp_outq_free(struct sctp_outq*);
1175 int sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk);
1176 int sctp_outq_sack(struct sctp_outq *, struct sctp_sackhdr *);
1177 int sctp_outq_is_empty(const struct sctp_outq *);
1178 void sctp_outq_restart(struct sctp_outq *);
1180 void sctp_retransmit(struct sctp_outq *, struct sctp_transport *,
1181 sctp_retransmit_reason_t);
1182 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1183 int sctp_outq_uncork(struct sctp_outq *);
1184 /* Uncork and flush an outqueue. */
1185 static inline void sctp_outq_cork(struct sctp_outq *q)
1190 /* These bind address data fields common between endpoints and associations */
1191 struct sctp_bind_addr {
1193 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1195 * SCTP Port: The local SCTP port number the endpoint is
1200 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1202 * Address List: The list of IP addresses that this instance
1203 * has bound. This information is passed to one's
1204 * peer(s) in INIT and INIT ACK chunks.
1206 struct list_head address_list;
1208 int malloced; /* Are we kfree()able? */
1211 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1212 void sctp_bind_addr_free(struct sctp_bind_addr *);
1213 int sctp_bind_addr_copy(struct sctp_bind_addr *dest,
1214 const struct sctp_bind_addr *src,
1215 sctp_scope_t scope, gfp_t gfp,
1217 int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
1218 const struct sctp_bind_addr *src,
1220 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1221 __u8 addr_state, gfp_t gfp);
1222 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1223 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1224 struct sctp_sock *);
1225 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *,
1226 struct sctp_sock *, struct sctp_sock *);
1227 int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
1228 const union sctp_addr *addr);
1229 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp,
1230 const union sctp_addr *addrs,
1232 struct sctp_sock *opt);
1233 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1236 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1237 __u16 port, gfp_t gfp);
1239 sctp_scope_t sctp_scope(const union sctp_addr *);
1240 int sctp_in_scope(const union sctp_addr *addr, const sctp_scope_t scope);
1241 int sctp_is_any(struct sock *sk, const union sctp_addr *addr);
1242 int sctp_addr_is_valid(const union sctp_addr *addr);
1245 /* What type of endpoint? */
1247 SCTP_EP_TYPE_SOCKET,
1248 SCTP_EP_TYPE_ASSOCIATION,
1249 } sctp_endpoint_type_t;
1252 * A common base class to bridge the implmentation view of a
1253 * socket (usually listening) endpoint versus an association's
1255 * This common structure is useful for several purposes:
1256 * 1) Common interface for lookup routines.
1257 * a) Subfunctions work for either endpoint or association
1258 * b) Single interface to lookup allows hiding the lookup lock rather
1259 * than acquiring it externally.
1260 * 2) Common interface for the inbound chunk handling/state machine.
1261 * 3) Common object handling routines for reference counting, etc.
1262 * 4) Disentangle association lookup from endpoint lookup, where we
1263 * do not have to find our endpoint to find our association.
1267 struct sctp_ep_common {
1268 /* Fields to help us manage our entries in the hash tables. */
1269 struct hlist_node node;
1272 /* Runtime type information. What kind of endpoint is this? */
1273 sctp_endpoint_type_t type;
1275 /* Some fields to help us manage this object.
1276 * refcnt - Reference count access to this object.
1277 * dead - Do not attempt to use this object.
1278 * malloced - Do we need to kfree this object?
1284 /* What socket does this endpoint belong to? */
1287 /* This is where we receive inbound chunks. */
1288 struct sctp_inq inqueue;
1290 /* This substructure includes the defining parameters of the
1292 * bind_addr.port is our shared port number.
1293 * bind_addr.address_list is our set of local IP addresses.
1295 struct sctp_bind_addr bind_addr;
1299 /* RFC Section 1.4 Key Terms
1301 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1302 * multi-homed host, an SCTP endpoint is represented to its peers as a
1303 * combination of a set of eligible destination transport addresses to
1304 * which SCTP packets can be sent and a set of eligible source
1305 * transport addresses from which SCTP packets can be received.
1306 * All transport addresses used by an SCTP endpoint must use the
1307 * same port number, but can use multiple IP addresses. A transport
1308 * address used by an SCTP endpoint must not be used by another
1309 * SCTP endpoint. In other words, a transport address is unique
1310 * to an SCTP endpoint.
1312 * From an implementation perspective, each socket has one of these.
1313 * A TCP-style socket will have exactly one association on one of
1314 * these. An UDP-style socket will have multiple associations hanging
1318 struct sctp_endpoint {
1319 /* Common substructure for endpoint and association. */
1320 struct sctp_ep_common base;
1322 /* Associations: A list of current associations and mappings
1323 * to the data consumers for each association. This
1324 * may be in the form of a hash table or other
1325 * implementation dependent structure. The data
1326 * consumers may be process identification
1327 * information such as file descriptors, named pipe
1328 * pointer, or table pointers dependent on how SCTP
1331 /* This is really a list of struct sctp_association entries. */
1332 struct list_head asocs;
1334 /* Secret Key: A secret key used by this endpoint to compute
1335 * the MAC. This SHOULD be a cryptographic quality
1336 * random number with a sufficient length.
1337 * Discussion in [RFC1750] can be helpful in
1338 * selection of the key.
1340 __u8 secret_key[SCTP_HOW_MANY_SECRETS][SCTP_SECRET_SIZE];
1345 /* digest: This is a digest of the sctp cookie. This field is
1346 * only used on the receive path when we try to validate
1347 * that the cookie has not been tampered with. We put
1348 * this here so we pre-allocate this once and can re-use
1353 /* sendbuf acct. policy. */
1354 __u32 sndbuf_policy;
1356 /* rcvbuf acct. policy. */
1357 __u32 rcvbuf_policy;
1359 /* SCTP AUTH: array of the HMACs that will be allocated
1360 * we need this per association so that we don't serialize
1362 struct crypto_hash **auth_hmacs;
1364 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1365 struct sctp_hmac_algo_param *auth_hmacs_list;
1367 /* SCTP-AUTH: chunks to authenticate encoded into parameter */
1368 struct sctp_chunks_param *auth_chunk_list;
1370 /* SCTP-AUTH: endpoint shared keys */
1371 struct list_head endpoint_shared_keys;
1372 __u16 active_key_id;
1375 /* Recover the outter endpoint structure. */
1376 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1378 struct sctp_endpoint *ep;
1380 ep = container_of(base, struct sctp_endpoint, base);
1384 /* These are function signatures for manipulating endpoints. */
1385 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1386 void sctp_endpoint_free(struct sctp_endpoint *);
1387 void sctp_endpoint_put(struct sctp_endpoint *);
1388 void sctp_endpoint_hold(struct sctp_endpoint *);
1389 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1390 struct sctp_association *sctp_endpoint_lookup_assoc(
1391 const struct sctp_endpoint *ep,
1392 const union sctp_addr *paddr,
1393 struct sctp_transport **);
1394 int sctp_endpoint_is_peeled_off(struct sctp_endpoint *,
1395 const union sctp_addr *);
1396 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1397 const union sctp_addr *);
1398 int sctp_has_association(const union sctp_addr *laddr,
1399 const union sctp_addr *paddr);
1401 int sctp_verify_init(const struct sctp_association *asoc, sctp_cid_t,
1402 sctp_init_chunk_t *peer_init, struct sctp_chunk *chunk,
1403 struct sctp_chunk **err_chunk);
1404 int sctp_process_init(struct sctp_association *, sctp_cid_t cid,
1405 const union sctp_addr *peer,
1406 sctp_init_chunk_t *init, gfp_t gfp);
1407 __u32 sctp_generate_tag(const struct sctp_endpoint *);
1408 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
1410 struct sctp_inithdr_host {
1413 __u16 num_outbound_streams;
1414 __u16 num_inbound_streams;
1420 * 12. Recommended Transmission Control Block (TCB) Parameters
1422 * This section details a recommended set of parameters that should
1423 * be contained within the TCB for an implementation. This section is
1424 * for illustrative purposes and should not be deemed as requirements
1425 * on an implementation or as an exhaustive list of all parameters
1426 * inside an SCTP TCB. Each implementation may need its own additional
1427 * parameters for optimization.
1431 /* Here we have information about each individual association. */
1432 struct sctp_association {
1434 /* A base structure common to endpoint and association.
1435 * In this context, it represents the associations's view
1436 * of the local endpoint of the association.
1438 struct sctp_ep_common base;
1440 /* Associations on the same socket. */
1441 struct list_head asocs;
1443 /* association id. */
1444 sctp_assoc_t assoc_id;
1446 /* This is our parent endpoint. */
1447 struct sctp_endpoint *ep;
1449 /* These are those association elements needed in the cookie. */
1450 struct sctp_cookie c;
1452 /* This is all information about our peer. */
1456 * Peer Rwnd : Current calculated value of the peer's rwnd.
1460 /* transport_addr_list
1462 * Peer : A list of SCTP transport addresses that the
1463 * Transport : peer is bound to. This information is derived
1464 * Address : from the INIT or INIT ACK and is used to
1465 * List : associate an inbound packet with a given
1466 * : association. Normally this information is
1467 * : hashed or keyed for quick lookup and access
1469 * : The list is also initialized with the list
1470 * : of addresses passed with the sctp_connectx()
1473 * It is a list of SCTP_transport's.
1475 struct list_head transport_addr_list;
1479 * Peer : A count of the number of peer addresses
1480 * Transport : in the Peer Transport Address List.
1484 __u16 transport_count;
1487 * The transport layer port number.
1493 * Primary : This is the current primary destination
1494 * Path : transport address of the peer endpoint. It
1495 * : may also specify a source transport address
1496 * : on this endpoint.
1498 * All of these paths live on transport_addr_list.
1500 * At the bakeoffs, we discovered that the intent of
1501 * primaryPath is that it only changes when the ULP
1502 * asks to have it changed. We add the activePath to
1503 * designate the connection we are currently using to
1504 * transmit new data and most control chunks.
1506 struct sctp_transport *primary_path;
1508 /* Cache the primary path address here, when we
1509 * need a an address for msg_name.
1511 union sctp_addr primary_addr;
1514 * The path that we are currently using to
1515 * transmit new data and most control chunks.
1517 struct sctp_transport *active_path;
1521 * RFC2960 6.4 Multi-homed SCTP Endpoints
1523 * Furthermore, when its peer is multi-homed, an
1524 * endpoint SHOULD try to retransmit a chunk to an
1525 * active destination transport address that is
1526 * different from the last destination address to
1527 * which the DATA chunk was sent.
1529 struct sctp_transport *retran_path;
1531 /* Pointer to last transport I have sent on. */
1532 struct sctp_transport *last_sent_to;
1534 /* This is the last transport I have received DATA on. */
1535 struct sctp_transport *last_data_from;
1538 * Mapping An array of bits or bytes indicating which out of
1539 * Array order TSN's have been received (relative to the
1540 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1541 * order packets have been received, this array
1542 * will be set to all zero. This structure may be
1543 * in the form of a circular buffer or bit array.
1545 * Last Rcvd : This is the last TSN received in
1546 * TSN : sequence. This value is set initially by
1547 * : taking the peer's Initial TSN, received in
1548 * : the INIT or INIT ACK chunk, and subtracting
1551 * Throughout most of the specification this is called the
1552 * "Cumulative TSN ACK Point". In this case, we
1553 * ignore the advice in 12.2 in favour of the term
1554 * used in the bulk of the text. This value is hidden
1555 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1557 struct sctp_tsnmap tsn_map;
1559 /* Ack State : This flag indicates if the next received
1560 * : packet is to be responded to with a
1561 * : SACK. This is initializedto 0. When a packet
1562 * : is received it is incremented. If this value
1563 * : reaches 2 or more, a SACK is sent and the
1564 * : value is reset to 0. Note: This is used only
1565 * : when no DATA chunks are received out of
1566 * : order. When DATA chunks are out of order,
1567 * : SACK's are not delayed (see Section 6).
1569 __u8 sack_needed; /* Do we need to sack the peer? */
1572 /* These are capabilities which our peer advertised. */
1573 __u8 ecn_capable:1, /* Can peer do ECN? */
1574 ipv4_address:1, /* Peer understands IPv4 addresses? */
1575 ipv6_address:1, /* Peer understands IPv6 addresses? */
1576 hostname_address:1, /* Peer understands DNS addresses? */
1577 asconf_capable:1, /* Does peer support ADDIP? */
1578 prsctp_capable:1, /* Can peer do PR-SCTP? */
1579 auth_capable:1; /* Is peer doing SCTP-AUTH? */
1581 __u32 adaptation_ind; /* Adaptation Code point. */
1583 /* This mask is used to disable sending the ASCONF chunk
1584 * with specified parameter to peer.
1586 __be16 addip_disabled_mask;
1588 struct sctp_inithdr_host i;
1592 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1593 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1594 * Initial TSN Value minus 1
1598 /* SCTP-AUTH: We need to know pears random number, hmac list
1599 * and authenticated chunk list. All that is part of the
1600 * cookie and these are just pointers to those locations
1602 sctp_random_param_t *peer_random;
1603 sctp_chunks_param_t *peer_chunks;
1604 sctp_hmac_algo_param_t *peer_hmacs;
1607 /* State : A state variable indicating what state the
1608 * : association is in, i.e. COOKIE-WAIT,
1609 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1610 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1612 * Note: No "CLOSED" state is illustrated since if a
1613 * association is "CLOSED" its TCB SHOULD be removed.
1615 * In this implementation we DO have a CLOSED
1616 * state which is used during initiation and shutdown.
1618 * State takes values from SCTP_STATE_*.
1622 /* The cookie life I award for any cookie. */
1623 struct timeval cookie_life;
1625 /* Overall : The overall association error count.
1626 * Error Count : [Clear this any time I get something.]
1628 int overall_error_count;
1630 /* These are the association's initial, max, and min RTO values.
1631 * These values will be initialized by system defaults, but can
1632 * be modified via the SCTP_RTOINFO socket option.
1634 unsigned long rto_initial;
1635 unsigned long rto_max;
1636 unsigned long rto_min;
1638 /* Maximum number of new data packets that can be sent in a burst. */
1641 /* This is the max_retrans value for the association. This value will
1642 * be initialized initialized from system defaults, but can be
1643 * modified by the SCTP_ASSOCINFO socket option.
1647 /* Maximum number of times the endpoint will retransmit INIT */
1648 __u16 max_init_attempts;
1650 /* How many times have we resent an INIT? */
1653 /* The largest timeout or RTO value to use in attempting an INIT */
1654 unsigned long max_init_timeo;
1656 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1657 * the destination address every heartbeat interval. This value
1658 * will be inherited by all new transports.
1660 unsigned long hbinterval;
1662 /* This is the max_retrans value for new transports in the
1667 /* Flag that path mtu update is pending */
1670 /* Association : The smallest PMTU discovered for all of the
1671 * PMTU : peer's transport addresses.
1675 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1678 /* SACK delay timeout */
1679 unsigned long sackdelay;
1683 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES];
1684 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1686 /* Transport to which SHUTDOWN chunk was last sent. */
1687 struct sctp_transport *shutdown_last_sent_to;
1689 /* How many times have we resent a SHUTDOWN */
1690 int shutdown_retries;
1692 /* Transport to which INIT chunk was last sent. */
1693 struct sctp_transport *init_last_sent_to;
1695 /* Next TSN : The next TSN number to be assigned to a new
1696 * : DATA chunk. This is sent in the INIT or INIT
1697 * : ACK chunk to the peer and incremented each
1698 * : time a DATA chunk is assigned a TSN
1699 * : (normally just prior to transmit or during
1705 * Last Rcvd : This is the last TSN received in sequence. This value
1706 * TSN : is set initially by taking the peer's Initial TSN,
1707 * : received in the INIT or INIT ACK chunk, and
1708 * : subtracting one from it.
1710 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1713 __u32 ctsn_ack_point;
1715 /* PR-SCTP Advanced.Peer.Ack.Point */
1716 __u32 adv_peer_ack_point;
1718 /* Highest TSN that is acknowledged by incoming SACKs. */
1719 __u32 highest_sacked;
1721 /* The number of unacknowledged data chunks. Reported through
1722 * the SCTP_STATUS sockopt.
1726 /* The total number of data chunks that we've had to retransmit
1727 * as the result of a T3 timer expiration
1729 __u32 rtx_data_chunks;
1731 /* This is the association's receive buffer space. This value is used
1732 * to set a_rwnd field in an INIT or a SACK chunk.
1736 /* This is the last advertised value of rwnd over a SACK chunk. */
1739 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1740 * to slop over a maximum of the association's frag_point.
1744 /* Keeps treack of rwnd pressure. This happens when we have
1745 * a window, but not recevie buffer (i.e small packets). This one
1746 * is releases slowly (1 PMTU at a time ).
1750 /* This is the sndbuf size in use for the association.
1751 * This corresponds to the sndbuf size for the association,
1752 * as specified in the sk->sndbuf.
1756 /* This is the amount of memory that this association has allocated
1757 * in the receive path at any given time.
1759 atomic_t rmem_alloc;
1761 /* This is the wait queue head for send requests waiting on
1762 * the association sndbuf space.
1764 wait_queue_head_t wait;
1766 /* The message size at which SCTP fragmentation will occur. */
1770 /* Counter used to count INIT errors. */
1771 int init_err_counter;
1773 /* Count the number of INIT cycles (for doubling timeout). */
1776 /* Default send parameters. */
1777 __u16 default_stream;
1778 __u16 default_flags;
1780 __u32 default_context;
1781 __u32 default_timetolive;
1783 /* Default receive parameters */
1784 __u32 default_rcv_context;
1786 /* This tracks outbound ssn for a given stream. */
1787 struct sctp_ssnmap *ssnmap;
1789 /* All outbound chunks go through this structure. */
1790 struct sctp_outq outqueue;
1792 /* A smart pipe that will handle reordering and fragmentation,
1793 * as well as handle passing events up to the ULP.
1795 struct sctp_ulpq ulpq;
1797 /* Last TSN that caused an ECNE Chunk to be sent. */
1798 __u32 last_ecne_tsn;
1800 /* Last TSN that caused a CWR Chunk to be sent. */
1803 /* How many duplicated TSNs have we seen? */
1806 /* Number of seconds of idle time before an association is closed.
1807 * In the association context, this is really used as a boolean
1808 * since the real timeout is stored in the timeouts array
1812 /* These are to support
1813 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1814 * and Enforcement of Flow and Message Limits"
1815 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1816 * or "ADDIP" for short.
1821 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1823 * R1) One and only one ASCONF Chunk MAY be in transit and
1824 * unacknowledged at any one time. If a sender, after sending
1825 * an ASCONF chunk, decides it needs to transfer another
1826 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1827 * returns from the previous ASCONF Chunk before sending a
1828 * subsequent ASCONF. Note this restriction binds each side,
1829 * so at any time two ASCONF may be in-transit on any given
1830 * association (one sent from each endpoint).
1832 * [This is our one-and-only-one ASCONF in flight. If we do
1833 * not have an ASCONF in flight, this is NULL.]
1835 struct sctp_chunk *addip_last_asconf;
1837 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
1839 * This is needed to implement itmes E1 - E4 of the updated
1840 * spec. Here is the justification:
1842 * Since the peer may bundle multiple ASCONF chunks toward us,
1843 * we now need the ability to cache multiple ACKs. The section
1844 * describes in detail how they are cached and cleaned up.
1846 struct list_head asconf_ack_list;
1848 /* These ASCONF chunks are waiting to be sent.
1850 * These chunaks can't be pushed to outqueue until receiving
1851 * ASCONF_ACK for the previous ASCONF indicated by
1852 * addip_last_asconf, so as to guarantee that only one ASCONF
1853 * is in flight at any time.
1855 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1857 * In defining the ASCONF Chunk transfer procedures, it is
1858 * essential that these transfers MUST NOT cause congestion
1859 * within the network. To achieve this, we place these
1860 * restrictions on the transfer of ASCONF Chunks:
1862 * R1) One and only one ASCONF Chunk MAY be in transit and
1863 * unacknowledged at any one time. If a sender, after sending
1864 * an ASCONF chunk, decides it needs to transfer another
1865 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1866 * returns from the previous ASCONF Chunk before sending a
1867 * subsequent ASCONF. Note this restriction binds each side,
1868 * so at any time two ASCONF may be in-transit on any given
1869 * association (one sent from each endpoint).
1872 * [I really think this is EXACTLY the sort of intelligence
1873 * which already resides in sctp_outq. Please move this
1874 * queue and its supporting logic down there. --piggy]
1876 struct list_head addip_chunk_list;
1878 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1880 * A2) A serial number should be assigned to the Chunk. The
1881 * serial number SHOULD be a monotonically increasing
1882 * number. The serial number SHOULD be initialized at
1883 * the start of the association to the same value as the
1884 * Initial TSN and every time a new ASCONF chunk is created
1885 * it is incremented by one after assigning the serial number
1886 * to the newly created chunk.
1889 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
1891 * Serial Number : 32 bits (unsigned integer)
1893 * This value represents a Serial Number for the ASCONF
1894 * Chunk. The valid range of Serial Number is from 0 to
1895 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
1896 * after reaching 4294967295.
1900 /* SCTP AUTH: list of the endpoint shared keys. These
1901 * keys are provided out of band by the user applicaton
1902 * and can't change during the lifetime of the association
1904 struct list_head endpoint_shared_keys;
1907 * The current generated assocaition shared key (secret)
1909 struct sctp_auth_bytes *asoc_shared_key;
1911 /* SCTP AUTH: hmac id of the first peer requested algorithm
1914 __u16 default_hmac_id;
1916 __u16 active_key_id;
1918 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */
1919 temp:1; /* Is it a temporary association? */
1923 /* An eyecatcher for determining if we are really looking at an
1924 * association data structure.
1927 SCTP_ASSOC_EYECATCHER = 0xa550c123,
1930 /* Recover the outter association structure. */
1931 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
1933 struct sctp_association *asoc;
1935 asoc = container_of(base, struct sctp_association, base);
1939 /* These are function signatures for manipulating associations. */
1942 struct sctp_association *
1943 sctp_association_new(const struct sctp_endpoint *, const struct sock *,
1944 sctp_scope_t scope, gfp_t gfp);
1945 void sctp_association_free(struct sctp_association *);
1946 void sctp_association_put(struct sctp_association *);
1947 void sctp_association_hold(struct sctp_association *);
1949 struct sctp_transport *sctp_assoc_choose_alter_transport(
1950 struct sctp_association *, struct sctp_transport *);
1951 void sctp_assoc_update_retran_path(struct sctp_association *);
1952 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
1953 const union sctp_addr *);
1954 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1955 const union sctp_addr *laddr);
1956 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
1957 const union sctp_addr *address,
1959 const int peer_state);
1960 void sctp_assoc_del_peer(struct sctp_association *asoc,
1961 const union sctp_addr *addr);
1962 void sctp_assoc_rm_peer(struct sctp_association *asoc,
1963 struct sctp_transport *peer);
1964 void sctp_assoc_control_transport(struct sctp_association *,
1965 struct sctp_transport *,
1966 sctp_transport_cmd_t, sctp_sn_error_t);
1967 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
1968 struct sctp_transport *sctp_assoc_is_match(struct sctp_association *,
1969 const union sctp_addr *,
1970 const union sctp_addr *);
1971 void sctp_assoc_migrate(struct sctp_association *, struct sock *);
1972 void sctp_assoc_update(struct sctp_association *old,
1973 struct sctp_association *new);
1975 __u32 sctp_association_get_next_tsn(struct sctp_association *);
1977 void sctp_assoc_sync_pmtu(struct sctp_association *);
1978 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned);
1979 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned);
1980 void sctp_assoc_set_primary(struct sctp_association *,
1981 struct sctp_transport *);
1982 void sctp_assoc_del_nonprimary_peers(struct sctp_association *,
1983 struct sctp_transport *);
1984 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *,
1985 sctp_scope_t, gfp_t);
1986 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
1987 struct sctp_cookie*,
1989 int sctp_assoc_set_id(struct sctp_association *, gfp_t);
1990 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc);
1991 struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
1992 const struct sctp_association *asoc,
1996 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1997 const union sctp_addr *ss2);
1998 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
2000 /* A convenience structure to parse out SCTP specific CMSGs. */
2001 typedef struct sctp_cmsgs {
2002 struct sctp_initmsg *init;
2003 struct sctp_sndrcvinfo *info;
2006 /* Structure for tracking memory objects */
2010 } sctp_dbg_objcnt_entry_t;
2012 #endif /* __sctp_structs_h__ */