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 <linux/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
;
164 /* Potentially-Failed.Max.Retrans sysctl value
166 * http://tools.ietf.org/html/draft-nishida-tsvwg-sctp-failover-05
171 * Policy for preforming sctp/socket accounting
172 * 0 - do socket level accounting, all assocs share sk_sndbuf
173 * 1 - do sctp accounting, each asoc may use sk_sndbuf bytes
178 * Policy for preforming sctp/socket accounting
179 * 0 - do socket level accounting, all assocs share sk_rcvbuf
180 * 1 - do sctp accounting, each asoc may use sk_rcvbuf bytes
184 /* The following variables are implementation specific. */
186 /* Default initialization values to be applied to new associations. */
188 __u16 max_outstreams
;
190 /* This is a list of groups of functions for each address
191 * family that we support.
193 struct list_head address_families
;
195 /* This is the hash of all endpoints. */
197 struct sctp_hashbucket
*ep_hashtable
;
199 /* This is the hash of all associations. */
201 struct sctp_hashbucket
*assoc_hashtable
;
203 /* This is the sctp port control hash. */
205 struct sctp_bind_hashbucket
*port_hashtable
;
207 /* This is the global local address list.
208 * We actively maintain this complete list of addresses on
209 * the system by catching address add/delete events.
211 * It is a list of sctp_sockaddr_entry.
213 struct list_head local_addr_list
;
214 int default_auto_asconf
;
215 struct list_head addr_waitq
;
216 struct timer_list addr_wq_timer
;
217 struct list_head auto_asconf_splist
;
218 spinlock_t addr_wq_lock
;
220 /* Lock that protects the local_addr_list writers */
221 spinlock_t addr_list_lock
;
223 /* Flag to indicate if addip is enabled. */
225 int addip_noauth_enable
;
227 /* Flag to indicate if PR-SCTP is enabled. */
230 /* Flag to idicate if SCTP-AUTH is enabled */
234 * Policy to control SCTP IPv4 address scoping
235 * 0 - Disable IPv4 address scoping
236 * 1 - Enable IPv4 address scoping
237 * 2 - Selectively allow only IPv4 private addresses
238 * 3 - Selectively allow only IPv4 link local address
240 int ipv4_scope_policy
;
242 /* Flag to indicate whether computing and verifying checksum
244 bool checksum_disable
;
246 /* Threshold for rwnd update SACKS. Receive buffer shifted this many
247 * bits is an indicator of when to send and window update SACK.
249 int rwnd_update_shift
;
251 /* Threshold for autoclose timeout, in seconds. */
252 unsigned long max_autoclose
;
255 #define sctp_rto_initial (sctp_globals.rto_initial)
256 #define sctp_rto_min (sctp_globals.rto_min)
257 #define sctp_rto_max (sctp_globals.rto_max)
258 #define sctp_rto_alpha (sctp_globals.rto_alpha)
259 #define sctp_rto_beta (sctp_globals.rto_beta)
260 #define sctp_max_burst (sctp_globals.max_burst)
261 #define sctp_valid_cookie_life (sctp_globals.valid_cookie_life)
262 #define sctp_cookie_preserve_enable (sctp_globals.cookie_preserve_enable)
263 #define sctp_max_retrans_association (sctp_globals.max_retrans_association)
264 #define sctp_sndbuf_policy (sctp_globals.sndbuf_policy)
265 #define sctp_rcvbuf_policy (sctp_globals.rcvbuf_policy)
266 #define sctp_max_retrans_path (sctp_globals.max_retrans_path)
267 #define sctp_pf_retrans (sctp_globals.pf_retrans)
268 #define sctp_max_retrans_init (sctp_globals.max_retrans_init)
269 #define sctp_sack_timeout (sctp_globals.sack_timeout)
270 #define sctp_hb_interval (sctp_globals.hb_interval)
271 #define sctp_max_instreams (sctp_globals.max_instreams)
272 #define sctp_max_outstreams (sctp_globals.max_outstreams)
273 #define sctp_address_families (sctp_globals.address_families)
274 #define sctp_ep_hashsize (sctp_globals.ep_hashsize)
275 #define sctp_ep_hashtable (sctp_globals.ep_hashtable)
276 #define sctp_assoc_hashsize (sctp_globals.assoc_hashsize)
277 #define sctp_assoc_hashtable (sctp_globals.assoc_hashtable)
278 #define sctp_port_hashsize (sctp_globals.port_hashsize)
279 #define sctp_port_hashtable (sctp_globals.port_hashtable)
280 #define sctp_local_addr_list (sctp_globals.local_addr_list)
281 #define sctp_local_addr_lock (sctp_globals.addr_list_lock)
282 #define sctp_auto_asconf_splist (sctp_globals.auto_asconf_splist)
283 #define sctp_addr_waitq (sctp_globals.addr_waitq)
284 #define sctp_addr_wq_timer (sctp_globals.addr_wq_timer)
285 #define sctp_addr_wq_lock (sctp_globals.addr_wq_lock)
286 #define sctp_default_auto_asconf (sctp_globals.default_auto_asconf)
287 #define sctp_scope_policy (sctp_globals.ipv4_scope_policy)
288 #define sctp_addip_enable (sctp_globals.addip_enable)
289 #define sctp_addip_noauth (sctp_globals.addip_noauth_enable)
290 #define sctp_prsctp_enable (sctp_globals.prsctp_enable)
291 #define sctp_auth_enable (sctp_globals.auth_enable)
292 #define sctp_checksum_disable (sctp_globals.checksum_disable)
293 #define sctp_rwnd_upd_shift (sctp_globals.rwnd_update_shift)
294 #define sctp_max_autoclose (sctp_globals.max_autoclose)
296 /* SCTP Socket type: UDP or TCP style. */
299 SCTP_SOCKET_UDP_HIGH_BANDWIDTH
,
301 } sctp_socket_type_t
;
303 /* Per socket SCTP information. */
305 /* inet_sock has to be the first member of sctp_sock */
306 struct inet_sock inet
;
307 /* What kind of a socket is this? */
308 sctp_socket_type_t type
;
310 /* PF_ family specific functions. */
313 /* Access to HMAC transform. */
314 struct crypto_hash
*hmac
;
316 /* What is our base endpointer? */
317 struct sctp_endpoint
*ep
;
319 struct sctp_bind_bucket
*bind_hash
;
320 /* Various Socket Options. */
321 __u16 default_stream
;
324 __u32 default_context
;
325 __u32 default_timetolive
;
326 __u32 default_rcv_context
;
329 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
330 * the destination address every heartbeat interval. This value
331 * will be inherited by all new associations.
335 /* This is the max_retrans value for new associations. */
338 /* The initial Path MTU to use for new associations. */
341 /* The default SACK delay timeout for new associations. */
345 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
348 struct sctp_initmsg initmsg
;
349 struct sctp_rtoinfo rtoinfo
;
350 struct sctp_paddrparams paddrparam
;
351 struct sctp_event_subscribe subscribe
;
352 struct sctp_assocparams assocparams
;
356 __u8 disable_fragments
;
358 __u8 frag_interleave
;
359 __u32 adaptation_ind
;
363 /* Receive to here while partial delivery is in effect. */
364 struct sk_buff_head pd_lobby
;
365 struct list_head auto_asconf_list
;
369 static inline struct sctp_sock
*sctp_sk(const struct sock
*sk
)
371 return (struct sctp_sock
*)sk
;
374 static inline struct sock
*sctp_opt2sk(const struct sctp_sock
*sp
)
376 return (struct sock
*)sp
;
379 #if IS_ENABLED(CONFIG_IPV6)
381 struct sctp_sock sctp
;
382 struct ipv6_pinfo inet6
;
384 #endif /* CONFIG_IPV6 */
387 /* This is our APPLICATION-SPECIFIC state cookie.
388 * THIS IS NOT DICTATED BY THE SPECIFICATION.
390 /* These are the parts of an association which we send in the cookie.
391 * Most of these are straight out of:
392 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
398 /* My : Tag expected in every inbound packet and sent
399 * Verification: in the INIT or INIT ACK chunk.
404 /* Peer's : Tag expected in every outbound packet except
405 * Verification: in the INIT chunk.
410 /* The rest of these are not from the spec, but really need to
414 /* My Tie Tag : Assist in discovering a restarting association. */
417 /* Peer's Tie Tag: Assist in discovering a restarting association. */
420 /* When does this cookie expire? */
421 struct timeval expiration
;
423 /* Number of inbound/outbound streams which are set
424 * and negotiated during the INIT process.
426 __u16 sinit_num_ostreams
;
427 __u16 sinit_max_instreams
;
429 /* This is the first sequence number I used. */
432 /* This holds the originating address of the INIT packet. */
433 union sctp_addr peer_addr
;
436 * Include the source port of the INIT-ACK
442 /* Padding for future use */
445 __u32 adaptation_ind
;
447 __u8 auth_random
[sizeof(sctp_paramhdr_t
) + SCTP_AUTH_RANDOM_LENGTH
];
448 __u8 auth_hmacs
[SCTP_AUTH_NUM_HMACS
* sizeof(__u16
) + 2];
449 __u8 auth_chunks
[sizeof(sctp_paramhdr_t
) + SCTP_AUTH_MAX_CHUNKS
];
451 /* This is a shim for my peer's INIT packet, followed by
452 * a copy of the raw address list of the association.
453 * The length of the raw address list is saved in the
454 * raw_addr_list_len field, which will be used at the time when
455 * the association TCB is re-constructed from the cookie.
457 __u32 raw_addr_list_len
;
458 struct sctp_init_chunk peer_init
[0];
462 /* The format of our cookie that we send to our peer. */
463 struct sctp_signed_cookie
{
464 __u8 signature
[SCTP_SECRET_SIZE
];
465 __u32 __pad
; /* force sctp_cookie alignment to 64 bits */
466 struct sctp_cookie c
;
469 /* This is another convenience type to allocate memory for address
470 * params for the maximum size and pass such structures around
473 union sctp_addr_param
{
474 struct sctp_paramhdr p
;
475 struct sctp_ipv4addr_param v4
;
476 struct sctp_ipv6addr_param v6
;
479 /* A convenience type to allow walking through the various
480 * parameters and avoid casting all over the place.
484 struct sctp_paramhdr
*p
;
485 struct sctp_cookie_preserve_param
*life
;
486 struct sctp_hostname_param
*dns
;
487 struct sctp_cookie_param
*cookie
;
488 struct sctp_supported_addrs_param
*sat
;
489 struct sctp_ipv4addr_param
*v4
;
490 struct sctp_ipv6addr_param
*v6
;
491 union sctp_addr_param
*addr
;
492 struct sctp_adaptation_ind_param
*aind
;
493 struct sctp_supported_ext_param
*ext
;
494 struct sctp_random_param
*random
;
495 struct sctp_chunks_param
*chunks
;
496 struct sctp_hmac_algo_param
*hmac_algo
;
497 struct sctp_addip_param
*addip
;
500 /* RFC 2960. Section 3.3.5 Heartbeat.
501 * Heartbeat Information: variable length
502 * The Sender-specific Heartbeat Info field should normally include
503 * information about the sender's current time when this HEARTBEAT
504 * chunk is sent and the destination transport address to which this
505 * HEARTBEAT is sent (see Section 8.3).
507 typedef struct sctp_sender_hb_info
{
508 struct sctp_paramhdr param_hdr
;
509 union sctp_addr daddr
;
510 unsigned long sent_at
;
512 } __packed sctp_sender_hb_info_t
;
515 * RFC 2960 1.3.2 Sequenced Delivery within Streams
517 * The term "stream" is used in SCTP to refer to a sequence of user
518 * messages that are to be delivered to the upper-layer protocol in
519 * order with respect to other messages within the same stream. This is
520 * in contrast to its usage in TCP, where it refers to a sequence of
521 * bytes (in this document a byte is assumed to be eight bits).
524 * This is the structure we use to track both our outbound and inbound
525 * SSN, or Stream Sequence Numbers.
534 struct sctp_stream in
;
535 struct sctp_stream out
;
539 struct sctp_ssnmap
*sctp_ssnmap_new(__u16 in
, __u16 out
,
541 void sctp_ssnmap_free(struct sctp_ssnmap
*map
);
542 void sctp_ssnmap_clear(struct sctp_ssnmap
*map
);
544 /* What is the current SSN number for this stream? */
545 static inline __u16
sctp_ssn_peek(struct sctp_stream
*stream
, __u16 id
)
547 return stream
->ssn
[id
];
550 /* Return the next SSN number for this stream. */
551 static inline __u16
sctp_ssn_next(struct sctp_stream
*stream
, __u16 id
)
553 return stream
->ssn
[id
]++;
556 /* Skip over this ssn and all below. */
557 static inline void sctp_ssn_skip(struct sctp_stream
*stream
, __u16 id
,
560 stream
->ssn
[id
] = ssn
+1;
564 * Pointers to address related SCTP functions.
565 * (i.e. things that depend on the address family.)
568 int (*sctp_xmit
) (struct sk_buff
*skb
,
569 struct sctp_transport
*);
570 int (*setsockopt
) (struct sock
*sk
,
574 unsigned int optlen
);
575 int (*getsockopt
) (struct sock
*sk
,
580 int (*compat_setsockopt
) (struct sock
*sk
,
584 unsigned int optlen
);
585 int (*compat_getsockopt
) (struct sock
*sk
,
590 void (*get_dst
) (struct sctp_transport
*t
,
591 union sctp_addr
*saddr
,
594 void (*get_saddr
) (struct sctp_sock
*sk
,
595 struct sctp_transport
*t
,
597 void (*copy_addrlist
) (struct list_head
*,
598 struct net_device
*);
599 int (*cmp_addr
) (const union sctp_addr
*addr1
,
600 const union sctp_addr
*addr2
);
601 void (*addr_copy
) (union sctp_addr
*dst
,
602 union sctp_addr
*src
);
603 void (*from_skb
) (union sctp_addr
*,
606 void (*from_sk
) (union sctp_addr
*,
608 void (*to_sk_saddr
) (union sctp_addr
*,
610 void (*to_sk_daddr
) (union sctp_addr
*,
612 void (*from_addr_param
) (union sctp_addr
*,
613 union sctp_addr_param
*,
614 __be16 port
, int iif
);
615 int (*to_addr_param
) (const union sctp_addr
*,
616 union sctp_addr_param
*);
617 int (*addr_valid
) (union sctp_addr
*,
619 const struct sk_buff
*);
620 sctp_scope_t (*scope
) (union sctp_addr
*);
621 void (*inaddr_any
) (union sctp_addr
*, __be16
);
622 int (*is_any
) (const union sctp_addr
*);
623 int (*available
) (union sctp_addr
*,
625 int (*skb_iif
) (const struct sk_buff
*sk
);
626 int (*is_ce
) (const struct sk_buff
*sk
);
627 void (*seq_dump_addr
)(struct seq_file
*seq
,
628 union sctp_addr
*addr
);
629 void (*ecn_capable
)(struct sock
*sk
);
630 __u16 net_header_len
;
632 sa_family_t sa_family
;
633 struct list_head list
;
636 struct sctp_af
*sctp_get_af_specific(sa_family_t
);
637 int sctp_register_af(struct sctp_af
*);
639 /* Protocol family functions. */
641 void (*event_msgname
)(struct sctp_ulpevent
*, char *, int *);
642 void (*skb_msgname
) (struct sk_buff
*, char *, int *);
643 int (*af_supported
) (sa_family_t
, struct sctp_sock
*);
644 int (*cmp_addr
) (const union sctp_addr
*,
645 const union sctp_addr
*,
647 int (*bind_verify
) (struct sctp_sock
*, union sctp_addr
*);
648 int (*send_verify
) (struct sctp_sock
*, union sctp_addr
*);
649 int (*supported_addrs
)(const struct sctp_sock
*, __be16
*);
650 struct sock
*(*create_accept_sk
) (struct sock
*sk
,
651 struct sctp_association
*asoc
);
652 void (*addr_v4map
) (struct sctp_sock
*, union sctp_addr
*);
657 /* Structure to track chunk fragments that have been acked, but peer
658 * fragments of the same message have not.
660 struct sctp_datamsg
{
661 /* Chunks waiting to be submitted to lower layer. */
662 struct list_head chunks
;
663 /* Reference counting. */
665 /* When is this message no longer interesting to the peer? */
666 unsigned long expires_at
;
667 /* Did the messenge fail to send? */
670 can_abandon
:1, /* can chunks from this message can be abandoned. */
671 can_delay
; /* should this message be Nagle delayed */
674 struct sctp_datamsg
*sctp_datamsg_from_user(struct sctp_association
*,
675 struct sctp_sndrcvinfo
*,
676 struct msghdr
*, int len
);
677 void sctp_datamsg_free(struct sctp_datamsg
*);
678 void sctp_datamsg_put(struct sctp_datamsg
*);
679 void sctp_chunk_fail(struct sctp_chunk
*, int error
);
680 int sctp_chunk_abandoned(struct sctp_chunk
*);
682 /* RFC2960 1.4 Key Terms
684 * o Chunk: A unit of information within an SCTP packet, consisting of
685 * a chunk header and chunk-specific content.
687 * As a matter of convenience, we remember the SCTP common header for
688 * each chunk as well as a few other header pointers...
691 struct list_head list
;
695 /* This is our link to the per-transport transmitted list. */
696 struct list_head transmitted_list
;
698 /* This field is used by chunks that hold fragmented data.
699 * For the first fragment this is the list that holds the rest of
700 * fragments. For the remaining fragments, this is the link to the
701 * frag_list maintained in the first fragment.
703 struct list_head frag_list
;
705 /* This points to the sk_buff containing the actual data. */
708 /* These are the SCTP headers by reverse order in a packet.
709 * Note that some of these may happen more than once. In that
710 * case, we point at the "current" one, whatever that means
711 * for that level of header.
714 /* We point this at the FIRST TLV parameter to chunk_hdr. */
715 union sctp_params param_hdr
;
718 struct sctp_datahdr
*data_hdr
;
719 struct sctp_inithdr
*init_hdr
;
720 struct sctp_sackhdr
*sack_hdr
;
721 struct sctp_heartbeathdr
*hb_hdr
;
722 struct sctp_sender_hb_info
*hbs_hdr
;
723 struct sctp_shutdownhdr
*shutdown_hdr
;
724 struct sctp_signed_cookie
*cookie_hdr
;
725 struct sctp_ecnehdr
*ecne_hdr
;
726 struct sctp_cwrhdr
*ecn_cwr_hdr
;
727 struct sctp_errhdr
*err_hdr
;
728 struct sctp_addiphdr
*addip_hdr
;
729 struct sctp_fwdtsn_hdr
*fwdtsn_hdr
;
730 struct sctp_authhdr
*auth_hdr
;
735 struct sctp_chunkhdr
*chunk_hdr
;
736 struct sctphdr
*sctp_hdr
;
738 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
739 struct sctp_sndrcvinfo sinfo
;
741 /* Which association does this belong to? */
742 struct sctp_association
*asoc
;
744 /* What endpoint received this chunk? */
745 struct sctp_ep_common
*rcvr
;
747 /* We fill this in if we are calculating RTT. */
748 unsigned long sent_at
;
750 /* What is the origin IP address for this chunk? */
751 union sctp_addr source
;
752 /* Destination address for this chunk. */
753 union sctp_addr dest
;
755 /* For outbound message, track all fragments for SEND_FAILED. */
756 struct sctp_datamsg
*msg
;
758 /* For an inbound chunk, this tells us where it came from.
759 * For an outbound chunk, it tells us where we'd like it to
760 * go. It is NULL if we have no preference.
762 struct sctp_transport
*transport
;
764 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO
765 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
766 * spec violates the principle premis that all chunks are processed
769 struct sk_buff
*auth_chunk
;
771 #define SCTP_CAN_FRTX 0x0
772 #define SCTP_NEED_FRTX 0x1
773 #define SCTP_DONT_FRTX 0x2
774 __u16 rtt_in_progress
:1, /* This chunk used for RTT calc? */
775 has_tsn
:1, /* Does this chunk have a TSN yet? */
776 has_ssn
:1, /* Does this chunk have a SSN yet? */
777 singleton
:1, /* Only chunk in the packet? */
778 end_of_packet
:1, /* Last chunk in the packet? */
779 ecn_ce_done
:1, /* Have we processed the ECN CE bit? */
780 pdiscard
:1, /* Discard the whole packet now? */
781 tsn_gap_acked
:1, /* Is this chunk acked by a GAP ACK? */
782 data_accepted
:1, /* At least 1 chunk accepted */
783 auth
:1, /* IN: was auth'ed | OUT: needs auth */
784 has_asconf
:1, /* IN: have seen an asconf before */
785 tsn_missing_report
:2, /* Data chunk missing counter. */
786 fast_retransmit
:2; /* Is this chunk fast retransmitted? */
789 void sctp_chunk_hold(struct sctp_chunk
*);
790 void sctp_chunk_put(struct sctp_chunk
*);
791 int sctp_user_addto_chunk(struct sctp_chunk
*chunk
, int off
, int len
,
793 void sctp_chunk_free(struct sctp_chunk
*);
794 void *sctp_addto_chunk(struct sctp_chunk
*, int len
, const void *data
);
795 void *sctp_addto_chunk_fixed(struct sctp_chunk
*, int len
, const void *data
);
796 struct sctp_chunk
*sctp_chunkify(struct sk_buff
*,
797 const struct sctp_association
*,
799 void sctp_init_addrs(struct sctp_chunk
*, union sctp_addr
*,
801 const union sctp_addr
*sctp_source(const struct sctp_chunk
*chunk
);
804 SCTP_ADDR_NEW
, /* new address added to assoc/ep */
805 SCTP_ADDR_SRC
, /* address can be used as source */
806 SCTP_ADDR_DEL
, /* address about to be deleted */
809 /* This is a structure for holding either an IPv6 or an IPv4 address. */
810 struct sctp_sockaddr_entry
{
811 struct list_head list
;
818 #define SCTP_ADDRESS_TICK_DELAY 500
820 typedef struct sctp_chunk
*(sctp_packet_phandler_t
)(struct sctp_association
*);
822 /* This structure holds lists of chunks as we are assembling for
826 /* These are the SCTP header values (host order) for the packet. */
828 __u16 destination_port
;
831 /* This contains the payload chunks. */
832 struct list_head chunk_list
;
834 /* This is the overhead of the sctp and ip headers. */
836 /* This is the total size of all chunks INCLUDING padding. */
839 /* The packet is destined for this transport address.
840 * The function we finally use to pass down to the next lower
841 * layer lives in the transport structure.
843 struct sctp_transport
*transport
;
845 /* pointer to the auth chunk for this packet */
846 struct sctp_chunk
*auth
;
848 u8 has_cookie_echo
:1, /* This packet contains a COOKIE-ECHO chunk. */
849 has_sack
:1, /* This packet contains a SACK chunk. */
850 has_auth
:1, /* This packet contains an AUTH chunk */
851 has_data
:1, /* This packet contains at least 1 DATA chunk */
852 ipfragok
:1, /* So let ip fragment this packet */
853 malloced
:1; /* Is it malloced? */
856 struct sctp_packet
*sctp_packet_init(struct sctp_packet
*,
857 struct sctp_transport
*,
858 __u16 sport
, __u16 dport
);
859 struct sctp_packet
*sctp_packet_config(struct sctp_packet
*, __u32 vtag
, int);
860 sctp_xmit_t
sctp_packet_transmit_chunk(struct sctp_packet
*,
861 struct sctp_chunk
*, int);
862 sctp_xmit_t
sctp_packet_append_chunk(struct sctp_packet
*,
863 struct sctp_chunk
*);
864 int sctp_packet_transmit(struct sctp_packet
*);
865 void sctp_packet_free(struct sctp_packet
*);
867 static inline int sctp_packet_empty(struct sctp_packet
*packet
)
869 return packet
->size
== packet
->overhead
;
872 /* This represents a remote transport address.
873 * For local transport addresses, we just use union sctp_addr.
875 * RFC2960 Section 1.4 Key Terms
877 * o Transport address: A Transport Address is traditionally defined
878 * by Network Layer address, Transport Layer protocol and Transport
879 * Layer port number. In the case of SCTP running over IP, a
880 * transport address is defined by the combination of an IP address
881 * and an SCTP port number (where SCTP is the Transport protocol).
883 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
885 * o The sender keeps a separate congestion control parameter set for
886 * each of the destination addresses it can send to (not each
887 * source-destination pair but for each destination). The parameters
888 * should decay if the address is not used for a long enough time
892 struct sctp_transport
{
893 /* A list of transports. */
894 struct list_head transports
;
896 /* Reference counting. */
899 /* RTO-Pending : A flag used to track if one of the DATA
900 * chunks sent to this address is currently being
901 * used to compute a RTT. If this flag is 0,
902 * the next DATA chunk sent to this destination
903 * should be used to compute a RTT and this flag
904 * should be set. Every time the RTT
905 * calculation completes (i.e. the DATA chunk
906 * is SACK'd) clear this flag.
911 * hb_sent : a flag that signals that we have a pending
916 /* Is the Path MTU update pending on this tranport */
919 /* Is this structure kfree()able? */
922 /* Has this transport moved the ctsn since we last sacked */
923 __u32 sack_generation
;
927 /* This is the peer's IP address and port. */
928 union sctp_addr ipaddr
;
930 /* These are the functions we call to handle LLP stuff. */
931 struct sctp_af
*af_specific
;
933 /* Which association do we belong to? */
934 struct sctp_association
*asoc
;
938 * 12.3 Per Transport Address Data
940 * For each destination transport address in the peer's
941 * address list derived from the INIT or INIT ACK chunk, a
942 * number of data elements needs to be maintained including:
944 /* RTO : The current retransmission timeout value. */
947 __u32 rtt
; /* This is the most recent RTT. */
949 /* RTTVAR : The current RTT variation. */
952 /* SRTT : The current smoothed round trip time. */
956 * These are the congestion stats.
958 /* cwnd : The current congestion window. */
959 __u32 cwnd
; /* This is the actual cwnd. */
961 /* ssthresh : The current slow start threshold value. */
964 /* partial : The tracking method for increase of cwnd when in
965 * bytes acked : congestion avoidance mode (see Section 6.2.2)
967 __u32 partial_bytes_acked
;
969 /* Data that has been sent, but not acknowledged. */
972 __u32 burst_limited
; /* Holds old cwnd when max.burst is applied */
975 struct dst_entry
*dst
;
976 /* Source address. */
977 union sctp_addr saddr
;
979 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
980 * the destination address every heartbeat interval.
982 unsigned long hbinterval
;
984 /* SACK delay timeout */
985 unsigned long sackdelay
;
988 /* When was the last time (in jiffies) that we heard from this
989 * transport? We use this to pick new active and retran paths.
991 unsigned long last_time_heard
;
993 /* Last time(in jiffies) when cwnd is reduced due to the congestion
994 * indication based on ECNE chunk.
996 unsigned long last_time_ecne_reduced
;
998 /* This is the max_retrans value for the transport and will
999 * be initialized from the assocs value. This can be changed
1000 * using the SCTP_SET_PEER_ADDR_PARAMS socket option.
1004 /* This is the partially failed retrans value for the transport
1005 * and will be initialized from the assocs value. This can be changed
1006 * using the SCTP_PEER_ADDR_THLDS socket option
1009 /* PMTU : The current known path MTU. */
1012 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1015 /* The number of times INIT has been sent on this transport. */
1016 int init_sent_count
;
1018 /* state : The current state of this destination,
1019 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
1023 /* These are the error stats for this destination. */
1025 /* Error count : The current error count for this destination. */
1026 unsigned short error_count
;
1028 /* Per : A timer used by each destination.
1032 * [Everywhere else in the text this is called T3-rtx. -ed]
1034 struct timer_list T3_rtx_timer
;
1036 /* Heartbeat timer is per destination. */
1037 struct timer_list hb_timer
;
1039 /* Timer to handle ICMP proto unreachable envets */
1040 struct timer_list proto_unreach_timer
;
1042 /* Since we're using per-destination retransmission timers
1043 * (see above), we're also using per-destination "transmitted"
1044 * queues. This probably ought to be a private struct
1045 * accessible only within the outqueue, but it's not, yet.
1047 struct list_head transmitted
;
1049 /* We build bundle-able packets for this transport here. */
1050 struct sctp_packet packet
;
1052 /* This is the list of transports that have chunks to send. */
1053 struct list_head send_ready
;
1055 /* State information saved for SFR_CACC algorithm. The key
1056 * idea in SFR_CACC is to maintain state at the sender on a
1057 * per-destination basis when a changeover happens.
1058 * char changeover_active;
1059 * char cycling_changeover;
1060 * __u32 next_tsn_at_change;
1061 * char cacc_saw_newack;
1064 /* An unsigned integer, which stores the next TSN to be
1065 * used by the sender, at the moment of changeover.
1067 __u32 next_tsn_at_change
;
1069 /* A flag which indicates the occurrence of a changeover */
1070 char changeover_active
;
1072 /* A flag which indicates whether the change of primary is
1073 * the first switch to this destination address during an
1076 char cycling_changeover
;
1078 /* A temporary flag, which is used during the processing of
1079 * a SACK to estimate the causative TSN(s)'s group.
1081 char cacc_saw_newack
;
1084 /* 64-bit random number sent with heartbeat. */
1088 struct sctp_transport
*sctp_transport_new(const union sctp_addr
*,
1090 void sctp_transport_set_owner(struct sctp_transport
*,
1091 struct sctp_association
*);
1092 void sctp_transport_route(struct sctp_transport
*, union sctp_addr
*,
1093 struct sctp_sock
*);
1094 void sctp_transport_pmtu(struct sctp_transport
*, struct sock
*sk
);
1095 void sctp_transport_free(struct sctp_transport
*);
1096 void sctp_transport_reset_timers(struct sctp_transport
*);
1097 void sctp_transport_hold(struct sctp_transport
*);
1098 void sctp_transport_put(struct sctp_transport
*);
1099 void sctp_transport_update_rto(struct sctp_transport
*, __u32
);
1100 void sctp_transport_raise_cwnd(struct sctp_transport
*, __u32
, __u32
);
1101 void sctp_transport_lower_cwnd(struct sctp_transport
*, sctp_lower_cwnd_t
);
1102 void sctp_transport_burst_limited(struct sctp_transport
*);
1103 void sctp_transport_burst_reset(struct sctp_transport
*);
1104 unsigned long sctp_transport_timeout(struct sctp_transport
*);
1105 void sctp_transport_reset(struct sctp_transport
*);
1106 void sctp_transport_update_pmtu(struct sock
*, struct sctp_transport
*, u32
);
1107 void sctp_transport_immediate_rtx(struct sctp_transport
*);
1110 /* This is the structure we use to queue packets as they come into
1111 * SCTP. We write packets to it and read chunks from it.
1114 /* This is actually a queue of sctp_chunk each
1115 * containing a partially decoded packet.
1117 struct list_head in_chunk_list
;
1118 /* This is the packet which is currently off the in queue and is
1119 * being worked on through the inbound chunk processing.
1121 struct sctp_chunk
*in_progress
;
1123 /* This is the delayed task to finish delivering inbound
1126 struct work_struct immediate
;
1128 int malloced
; /* Is this structure kfree()able? */
1131 void sctp_inq_init(struct sctp_inq
*);
1132 void sctp_inq_free(struct sctp_inq
*);
1133 void sctp_inq_push(struct sctp_inq
*, struct sctp_chunk
*packet
);
1134 struct sctp_chunk
*sctp_inq_pop(struct sctp_inq
*);
1135 struct sctp_chunkhdr
*sctp_inq_peek(struct sctp_inq
*);
1136 void sctp_inq_set_th_handler(struct sctp_inq
*, work_func_t
);
1138 /* This is the structure we use to hold outbound chunks. You push
1139 * chunks in and they automatically pop out the other end as bundled
1140 * packets (it calls (*output_handler)()).
1142 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1143 * and 8.2 of the v13 draft.
1145 * It handles retransmissions. The connection to the timeout portion
1146 * of the state machine is through sctp_..._timeout() and timeout_handler.
1148 * If you feed it SACKs, it will eat them.
1150 * If you give it big chunks, it will fragment them.
1152 * It assigns TSN's to data chunks. This happens at the last possible
1153 * instant before transmission.
1155 * When free()'d, it empties itself out via output_handler().
1158 struct sctp_association
*asoc
;
1160 /* Data pending that has never been transmitted. */
1161 struct list_head out_chunk_list
;
1163 unsigned int out_qlen
; /* Total length of queued data chunks. */
1165 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1168 /* These are control chunks we want to send. */
1169 struct list_head control_chunk_list
;
1171 /* These are chunks that have been sacked but are above the
1172 * CTSN, or cumulative tsn ack point.
1174 struct list_head sacked
;
1176 /* Put chunks on this list to schedule them for
1179 struct list_head retransmit
;
1181 /* Put chunks on this list to save them for FWD TSN processing as
1182 * they were abandoned.
1184 struct list_head abandoned
;
1186 /* How many unackd bytes do we have in-flight? */
1187 __u32 outstanding_bytes
;
1189 /* Are we doing fast-rtx on this queue */
1195 /* Is this structure empty? */
1198 /* Are we kfree()able? */
1202 void sctp_outq_init(struct sctp_association
*, struct sctp_outq
*);
1203 void sctp_outq_teardown(struct sctp_outq
*);
1204 void sctp_outq_free(struct sctp_outq
*);
1205 int sctp_outq_tail(struct sctp_outq
*, struct sctp_chunk
*chunk
);
1206 int sctp_outq_sack(struct sctp_outq
*, struct sctp_sackhdr
*);
1207 int sctp_outq_is_empty(const struct sctp_outq
*);
1208 void sctp_outq_restart(struct sctp_outq
*);
1210 void sctp_retransmit(struct sctp_outq
*, struct sctp_transport
*,
1211 sctp_retransmit_reason_t
);
1212 void sctp_retransmit_mark(struct sctp_outq
*, struct sctp_transport
*, __u8
);
1213 int sctp_outq_uncork(struct sctp_outq
*);
1214 /* Uncork and flush an outqueue. */
1215 static inline void sctp_outq_cork(struct sctp_outq
*q
)
1220 /* These bind address data fields common between endpoints and associations */
1221 struct sctp_bind_addr
{
1223 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1225 * SCTP Port: The local SCTP port number the endpoint is
1230 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1232 * Address List: The list of IP addresses that this instance
1233 * has bound. This information is passed to one's
1234 * peer(s) in INIT and INIT ACK chunks.
1236 struct list_head address_list
;
1238 int malloced
; /* Are we kfree()able? */
1241 void sctp_bind_addr_init(struct sctp_bind_addr
*, __u16 port
);
1242 void sctp_bind_addr_free(struct sctp_bind_addr
*);
1243 int sctp_bind_addr_copy(struct sctp_bind_addr
*dest
,
1244 const struct sctp_bind_addr
*src
,
1245 sctp_scope_t scope
, gfp_t gfp
,
1247 int sctp_bind_addr_dup(struct sctp_bind_addr
*dest
,
1248 const struct sctp_bind_addr
*src
,
1250 int sctp_add_bind_addr(struct sctp_bind_addr
*, union sctp_addr
*,
1251 __u8 addr_state
, gfp_t gfp
);
1252 int sctp_del_bind_addr(struct sctp_bind_addr
*, union sctp_addr
*);
1253 int sctp_bind_addr_match(struct sctp_bind_addr
*, const union sctp_addr
*,
1254 struct sctp_sock
*);
1255 int sctp_bind_addr_conflict(struct sctp_bind_addr
*, const union sctp_addr
*,
1256 struct sctp_sock
*, struct sctp_sock
*);
1257 int sctp_bind_addr_state(const struct sctp_bind_addr
*bp
,
1258 const union sctp_addr
*addr
);
1259 union sctp_addr
*sctp_find_unmatch_addr(struct sctp_bind_addr
*bp
,
1260 const union sctp_addr
*addrs
,
1262 struct sctp_sock
*opt
);
1263 union sctp_params
sctp_bind_addrs_to_raw(const struct sctp_bind_addr
*bp
,
1266 int sctp_raw_to_bind_addrs(struct sctp_bind_addr
*bp
, __u8
*raw
, int len
,
1267 __u16 port
, gfp_t gfp
);
1269 sctp_scope_t
sctp_scope(const union sctp_addr
*);
1270 int sctp_in_scope(const union sctp_addr
*addr
, const sctp_scope_t scope
);
1271 int sctp_is_any(struct sock
*sk
, const union sctp_addr
*addr
);
1272 int sctp_addr_is_valid(const union sctp_addr
*addr
);
1273 int sctp_is_ep_boundall(struct sock
*sk
);
1276 /* What type of endpoint? */
1278 SCTP_EP_TYPE_SOCKET
,
1279 SCTP_EP_TYPE_ASSOCIATION
,
1280 } sctp_endpoint_type_t
;
1283 * A common base class to bridge the implmentation view of a
1284 * socket (usually listening) endpoint versus an association's
1286 * This common structure is useful for several purposes:
1287 * 1) Common interface for lookup routines.
1288 * a) Subfunctions work for either endpoint or association
1289 * b) Single interface to lookup allows hiding the lookup lock rather
1290 * than acquiring it externally.
1291 * 2) Common interface for the inbound chunk handling/state machine.
1292 * 3) Common object handling routines for reference counting, etc.
1293 * 4) Disentangle association lookup from endpoint lookup, where we
1294 * do not have to find our endpoint to find our association.
1298 struct sctp_ep_common
{
1299 /* Fields to help us manage our entries in the hash tables. */
1300 struct hlist_node node
;
1303 /* Runtime type information. What kind of endpoint is this? */
1304 sctp_endpoint_type_t type
;
1306 /* Some fields to help us manage this object.
1307 * refcnt - Reference count access to this object.
1308 * dead - Do not attempt to use this object.
1309 * malloced - Do we need to kfree this object?
1315 /* What socket does this endpoint belong to? */
1318 /* This is where we receive inbound chunks. */
1319 struct sctp_inq inqueue
;
1321 /* This substructure includes the defining parameters of the
1323 * bind_addr.port is our shared port number.
1324 * bind_addr.address_list is our set of local IP addresses.
1326 struct sctp_bind_addr bind_addr
;
1330 /* RFC Section 1.4 Key Terms
1332 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1333 * multi-homed host, an SCTP endpoint is represented to its peers as a
1334 * combination of a set of eligible destination transport addresses to
1335 * which SCTP packets can be sent and a set of eligible source
1336 * transport addresses from which SCTP packets can be received.
1337 * All transport addresses used by an SCTP endpoint must use the
1338 * same port number, but can use multiple IP addresses. A transport
1339 * address used by an SCTP endpoint must not be used by another
1340 * SCTP endpoint. In other words, a transport address is unique
1341 * to an SCTP endpoint.
1343 * From an implementation perspective, each socket has one of these.
1344 * A TCP-style socket will have exactly one association on one of
1345 * these. An UDP-style socket will have multiple associations hanging
1349 struct sctp_endpoint
{
1350 /* Common substructure for endpoint and association. */
1351 struct sctp_ep_common base
;
1353 /* Associations: A list of current associations and mappings
1354 * to the data consumers for each association. This
1355 * may be in the form of a hash table or other
1356 * implementation dependent structure. The data
1357 * consumers may be process identification
1358 * information such as file descriptors, named pipe
1359 * pointer, or table pointers dependent on how SCTP
1362 /* This is really a list of struct sctp_association entries. */
1363 struct list_head asocs
;
1365 /* Secret Key: A secret key used by this endpoint to compute
1366 * the MAC. This SHOULD be a cryptographic quality
1367 * random number with a sufficient length.
1368 * Discussion in [RFC1750] can be helpful in
1369 * selection of the key.
1371 __u8 secret_key
[SCTP_HOW_MANY_SECRETS
][SCTP_SECRET_SIZE
];
1376 /* digest: This is a digest of the sctp cookie. This field is
1377 * only used on the receive path when we try to validate
1378 * that the cookie has not been tampered with. We put
1379 * this here so we pre-allocate this once and can re-use
1384 /* sendbuf acct. policy. */
1385 __u32 sndbuf_policy
;
1387 /* rcvbuf acct. policy. */
1388 __u32 rcvbuf_policy
;
1390 /* SCTP AUTH: array of the HMACs that will be allocated
1391 * we need this per association so that we don't serialize
1393 struct crypto_hash
**auth_hmacs
;
1395 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1396 struct sctp_hmac_algo_param
*auth_hmacs_list
;
1398 /* SCTP-AUTH: chunks to authenticate encoded into parameter */
1399 struct sctp_chunks_param
*auth_chunk_list
;
1401 /* SCTP-AUTH: endpoint shared keys */
1402 struct list_head endpoint_shared_keys
;
1403 __u16 active_key_id
;
1406 /* Recover the outter endpoint structure. */
1407 static inline struct sctp_endpoint
*sctp_ep(struct sctp_ep_common
*base
)
1409 struct sctp_endpoint
*ep
;
1411 ep
= container_of(base
, struct sctp_endpoint
, base
);
1415 /* These are function signatures for manipulating endpoints. */
1416 struct sctp_endpoint
*sctp_endpoint_new(struct sock
*, gfp_t
);
1417 void sctp_endpoint_free(struct sctp_endpoint
*);
1418 void sctp_endpoint_put(struct sctp_endpoint
*);
1419 void sctp_endpoint_hold(struct sctp_endpoint
*);
1420 void sctp_endpoint_add_asoc(struct sctp_endpoint
*, struct sctp_association
*);
1421 struct sctp_association
*sctp_endpoint_lookup_assoc(
1422 const struct sctp_endpoint
*ep
,
1423 const union sctp_addr
*paddr
,
1424 struct sctp_transport
**);
1425 int sctp_endpoint_is_peeled_off(struct sctp_endpoint
*,
1426 const union sctp_addr
*);
1427 struct sctp_endpoint
*sctp_endpoint_is_match(struct sctp_endpoint
*,
1428 const union sctp_addr
*);
1429 int sctp_has_association(const union sctp_addr
*laddr
,
1430 const union sctp_addr
*paddr
);
1432 int sctp_verify_init(const struct sctp_association
*asoc
, sctp_cid_t
,
1433 sctp_init_chunk_t
*peer_init
, struct sctp_chunk
*chunk
,
1434 struct sctp_chunk
**err_chunk
);
1435 int sctp_process_init(struct sctp_association
*, struct sctp_chunk
*chunk
,
1436 const union sctp_addr
*peer
,
1437 sctp_init_chunk_t
*init
, gfp_t gfp
);
1438 __u32
sctp_generate_tag(const struct sctp_endpoint
*);
1439 __u32
sctp_generate_tsn(const struct sctp_endpoint
*);
1441 struct sctp_inithdr_host
{
1444 __u16 num_outbound_streams
;
1445 __u16 num_inbound_streams
;
1451 * 12. Recommended Transmission Control Block (TCB) Parameters
1453 * This section details a recommended set of parameters that should
1454 * be contained within the TCB for an implementation. This section is
1455 * for illustrative purposes and should not be deemed as requirements
1456 * on an implementation or as an exhaustive list of all parameters
1457 * inside an SCTP TCB. Each implementation may need its own additional
1458 * parameters for optimization.
1462 /* Here we have information about each individual association. */
1463 struct sctp_association
{
1465 /* A base structure common to endpoint and association.
1466 * In this context, it represents the associations's view
1467 * of the local endpoint of the association.
1469 struct sctp_ep_common base
;
1471 /* Associations on the same socket. */
1472 struct list_head asocs
;
1474 /* association id. */
1475 sctp_assoc_t assoc_id
;
1477 /* This is our parent endpoint. */
1478 struct sctp_endpoint
*ep
;
1480 /* These are those association elements needed in the cookie. */
1481 struct sctp_cookie c
;
1483 /* This is all information about our peer. */
1487 * Peer Rwnd : Current calculated value of the peer's rwnd.
1491 /* transport_addr_list
1493 * Peer : A list of SCTP transport addresses that the
1494 * Transport : peer is bound to. This information is derived
1495 * Address : from the INIT or INIT ACK and is used to
1496 * List : associate an inbound packet with a given
1497 * : association. Normally this information is
1498 * : hashed or keyed for quick lookup and access
1500 * : The list is also initialized with the list
1501 * : of addresses passed with the sctp_connectx()
1504 * It is a list of SCTP_transport's.
1506 struct list_head transport_addr_list
;
1510 * Peer : A count of the number of peer addresses
1511 * Transport : in the Peer Transport Address List.
1515 __u16 transport_count
;
1518 * The transport layer port number.
1524 * Primary : This is the current primary destination
1525 * Path : transport address of the peer endpoint. It
1526 * : may also specify a source transport address
1527 * : on this endpoint.
1529 * All of these paths live on transport_addr_list.
1531 * At the bakeoffs, we discovered that the intent of
1532 * primaryPath is that it only changes when the ULP
1533 * asks to have it changed. We add the activePath to
1534 * designate the connection we are currently using to
1535 * transmit new data and most control chunks.
1537 struct sctp_transport
*primary_path
;
1539 /* Cache the primary path address here, when we
1540 * need a an address for msg_name.
1542 union sctp_addr primary_addr
;
1545 * The path that we are currently using to
1546 * transmit new data and most control chunks.
1548 struct sctp_transport
*active_path
;
1552 * RFC2960 6.4 Multi-homed SCTP Endpoints
1554 * Furthermore, when its peer is multi-homed, an
1555 * endpoint SHOULD try to retransmit a chunk to an
1556 * active destination transport address that is
1557 * different from the last destination address to
1558 * which the DATA chunk was sent.
1560 struct sctp_transport
*retran_path
;
1562 /* Pointer to last transport I have sent on. */
1563 struct sctp_transport
*last_sent_to
;
1565 /* This is the last transport I have received DATA on. */
1566 struct sctp_transport
*last_data_from
;
1569 * Mapping An array of bits or bytes indicating which out of
1570 * Array order TSN's have been received (relative to the
1571 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1572 * order packets have been received, this array
1573 * will be set to all zero. This structure may be
1574 * in the form of a circular buffer or bit array.
1576 * Last Rcvd : This is the last TSN received in
1577 * TSN : sequence. This value is set initially by
1578 * : taking the peer's Initial TSN, received in
1579 * : the INIT or INIT ACK chunk, and subtracting
1582 * Throughout most of the specification this is called the
1583 * "Cumulative TSN ACK Point". In this case, we
1584 * ignore the advice in 12.2 in favour of the term
1585 * used in the bulk of the text. This value is hidden
1586 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1588 struct sctp_tsnmap tsn_map
;
1590 /* Ack State : This flag indicates if the next received
1591 * : packet is to be responded to with a
1592 * : SACK. This is initializedto 0. When a packet
1593 * : is received it is incremented. If this value
1594 * : reaches 2 or more, a SACK is sent and the
1595 * : value is reset to 0. Note: This is used only
1596 * : when no DATA chunks are received out of
1597 * : order. When DATA chunks are out of order,
1598 * : SACK's are not delayed (see Section 6).
1600 __u8 sack_needed
; /* Do we need to sack the peer? */
1602 __u32 sack_generation
;
1604 /* These are capabilities which our peer advertised. */
1605 __u8 ecn_capable
:1, /* Can peer do ECN? */
1606 ipv4_address
:1, /* Peer understands IPv4 addresses? */
1607 ipv6_address
:1, /* Peer understands IPv6 addresses? */
1608 hostname_address
:1, /* Peer understands DNS addresses? */
1609 asconf_capable
:1, /* Does peer support ADDIP? */
1610 prsctp_capable
:1, /* Can peer do PR-SCTP? */
1611 auth_capable
:1; /* Is peer doing SCTP-AUTH? */
1613 __u32 adaptation_ind
; /* Adaptation Code point. */
1615 /* This mask is used to disable sending the ASCONF chunk
1616 * with specified parameter to peer.
1618 __be16 addip_disabled_mask
;
1620 struct sctp_inithdr_host i
;
1624 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1625 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1626 * Initial TSN Value minus 1
1630 /* SCTP-AUTH: We need to know pears random number, hmac list
1631 * and authenticated chunk list. All that is part of the
1632 * cookie and these are just pointers to those locations
1634 sctp_random_param_t
*peer_random
;
1635 sctp_chunks_param_t
*peer_chunks
;
1636 sctp_hmac_algo_param_t
*peer_hmacs
;
1639 /* State : A state variable indicating what state the
1640 * : association is in, i.e. COOKIE-WAIT,
1641 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1642 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1644 * Note: No "CLOSED" state is illustrated since if a
1645 * association is "CLOSED" its TCB SHOULD be removed.
1647 * In this implementation we DO have a CLOSED
1648 * state which is used during initiation and shutdown.
1650 * State takes values from SCTP_STATE_*.
1654 /* The cookie life I award for any cookie. */
1655 struct timeval cookie_life
;
1657 /* Overall : The overall association error count.
1658 * Error Count : [Clear this any time I get something.]
1660 int overall_error_count
;
1662 /* These are the association's initial, max, and min RTO values.
1663 * These values will be initialized by system defaults, but can
1664 * be modified via the SCTP_RTOINFO socket option.
1666 unsigned long rto_initial
;
1667 unsigned long rto_max
;
1668 unsigned long rto_min
;
1670 /* Maximum number of new data packets that can be sent in a burst. */
1673 /* This is the max_retrans value for the association. This value will
1674 * be initialized initialized from system defaults, but can be
1675 * modified by the SCTP_ASSOCINFO socket option.
1679 /* This is the partially failed retrans value for the transport
1680 * and will be initialized from the assocs value. This can be
1681 * changed using the SCTP_PEER_ADDR_THLDS socket option
1685 /* Maximum number of times the endpoint will retransmit INIT */
1686 __u16 max_init_attempts
;
1688 /* How many times have we resent an INIT? */
1691 /* The largest timeout or RTO value to use in attempting an INIT */
1692 unsigned long max_init_timeo
;
1694 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1695 * the destination address every heartbeat interval. This value
1696 * will be inherited by all new transports.
1698 unsigned long hbinterval
;
1700 /* This is the max_retrans value for new transports in the
1705 /* Flag that path mtu update is pending */
1708 /* Association : The smallest PMTU discovered for all of the
1709 * PMTU : peer's transport addresses.
1713 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1716 /* SACK delay timeout */
1717 unsigned long sackdelay
;
1721 unsigned long timeouts
[SCTP_NUM_TIMEOUT_TYPES
];
1722 struct timer_list timers
[SCTP_NUM_TIMEOUT_TYPES
];
1724 /* Transport to which SHUTDOWN chunk was last sent. */
1725 struct sctp_transport
*shutdown_last_sent_to
;
1727 /* How many times have we resent a SHUTDOWN */
1728 int shutdown_retries
;
1730 /* Transport to which INIT chunk was last sent. */
1731 struct sctp_transport
*init_last_sent_to
;
1733 /* Next TSN : The next TSN number to be assigned to a new
1734 * : DATA chunk. This is sent in the INIT or INIT
1735 * : ACK chunk to the peer and incremented each
1736 * : time a DATA chunk is assigned a TSN
1737 * : (normally just prior to transmit or during
1743 * Last Rcvd : This is the last TSN received in sequence. This value
1744 * TSN : is set initially by taking the peer's Initial TSN,
1745 * : received in the INIT or INIT ACK chunk, and
1746 * : subtracting one from it.
1748 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1751 __u32 ctsn_ack_point
;
1753 /* PR-SCTP Advanced.Peer.Ack.Point */
1754 __u32 adv_peer_ack_point
;
1756 /* Highest TSN that is acknowledged by incoming SACKs. */
1757 __u32 highest_sacked
;
1759 /* TSN marking the fast recovery exit point */
1760 __u32 fast_recovery_exit
;
1762 /* Flag to track the current fast recovery state */
1765 /* The number of unacknowledged data chunks. Reported through
1766 * the SCTP_STATUS sockopt.
1770 /* The total number of data chunks that we've had to retransmit
1771 * as the result of a T3 timer expiration
1773 __u32 rtx_data_chunks
;
1775 /* This is the association's receive buffer space. This value is used
1776 * to set a_rwnd field in an INIT or a SACK chunk.
1780 /* This is the last advertised value of rwnd over a SACK chunk. */
1783 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1784 * to slop over a maximum of the association's frag_point.
1788 /* Keeps treack of rwnd pressure. This happens when we have
1789 * a window, but not recevie buffer (i.e small packets). This one
1790 * is releases slowly (1 PMTU at a time ).
1794 /* This is the sndbuf size in use for the association.
1795 * This corresponds to the sndbuf size for the association,
1796 * as specified in the sk->sndbuf.
1800 /* This is the amount of memory that this association has allocated
1801 * in the receive path at any given time.
1803 atomic_t rmem_alloc
;
1805 /* This is the wait queue head for send requests waiting on
1806 * the association sndbuf space.
1808 wait_queue_head_t wait
;
1810 /* The message size at which SCTP fragmentation will occur. */
1814 /* Counter used to count INIT errors. */
1815 int init_err_counter
;
1817 /* Count the number of INIT cycles (for doubling timeout). */
1820 /* Default send parameters. */
1821 __u16 default_stream
;
1822 __u16 default_flags
;
1824 __u32 default_context
;
1825 __u32 default_timetolive
;
1827 /* Default receive parameters */
1828 __u32 default_rcv_context
;
1830 /* This tracks outbound ssn for a given stream. */
1831 struct sctp_ssnmap
*ssnmap
;
1833 /* All outbound chunks go through this structure. */
1834 struct sctp_outq outqueue
;
1836 /* A smart pipe that will handle reordering and fragmentation,
1837 * as well as handle passing events up to the ULP.
1839 struct sctp_ulpq ulpq
;
1841 /* Last TSN that caused an ECNE Chunk to be sent. */
1842 __u32 last_ecne_tsn
;
1844 /* Last TSN that caused a CWR Chunk to be sent. */
1847 /* How many duplicated TSNs have we seen? */
1850 /* Number of seconds of idle time before an association is closed.
1851 * In the association context, this is really used as a boolean
1852 * since the real timeout is stored in the timeouts array
1856 /* These are to support
1857 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1858 * and Enforcement of Flow and Message Limits"
1859 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1860 * or "ADDIP" for short.
1865 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1867 * R1) One and only one ASCONF Chunk MAY be in transit and
1868 * unacknowledged at any one time. If a sender, after sending
1869 * an ASCONF chunk, decides it needs to transfer another
1870 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1871 * returns from the previous ASCONF Chunk before sending a
1872 * subsequent ASCONF. Note this restriction binds each side,
1873 * so at any time two ASCONF may be in-transit on any given
1874 * association (one sent from each endpoint).
1876 * [This is our one-and-only-one ASCONF in flight. If we do
1877 * not have an ASCONF in flight, this is NULL.]
1879 struct sctp_chunk
*addip_last_asconf
;
1881 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
1883 * This is needed to implement itmes E1 - E4 of the updated
1884 * spec. Here is the justification:
1886 * Since the peer may bundle multiple ASCONF chunks toward us,
1887 * we now need the ability to cache multiple ACKs. The section
1888 * describes in detail how they are cached and cleaned up.
1890 struct list_head asconf_ack_list
;
1892 /* These ASCONF chunks are waiting to be sent.
1894 * These chunaks can't be pushed to outqueue until receiving
1895 * ASCONF_ACK for the previous ASCONF indicated by
1896 * addip_last_asconf, so as to guarantee that only one ASCONF
1897 * is in flight at any time.
1899 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1901 * In defining the ASCONF Chunk transfer procedures, it is
1902 * essential that these transfers MUST NOT cause congestion
1903 * within the network. To achieve this, we place these
1904 * restrictions on the transfer of ASCONF Chunks:
1906 * R1) One and only one ASCONF Chunk MAY be in transit and
1907 * unacknowledged at any one time. If a sender, after sending
1908 * an ASCONF chunk, decides it needs to transfer another
1909 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1910 * returns from the previous ASCONF Chunk before sending a
1911 * subsequent ASCONF. Note this restriction binds each side,
1912 * so at any time two ASCONF may be in-transit on any given
1913 * association (one sent from each endpoint).
1916 * [I really think this is EXACTLY the sort of intelligence
1917 * which already resides in sctp_outq. Please move this
1918 * queue and its supporting logic down there. --piggy]
1920 struct list_head addip_chunk_list
;
1922 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1924 * A2) A serial number should be assigned to the Chunk. The
1925 * serial number SHOULD be a monotonically increasing
1926 * number. The serial number SHOULD be initialized at
1927 * the start of the association to the same value as the
1928 * Initial TSN and every time a new ASCONF chunk is created
1929 * it is incremented by one after assigning the serial number
1930 * to the newly created chunk.
1933 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
1935 * Serial Number : 32 bits (unsigned integer)
1937 * This value represents a Serial Number for the ASCONF
1938 * Chunk. The valid range of Serial Number is from 0 to
1939 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
1940 * after reaching 4294967295.
1943 union sctp_addr
*asconf_addr_del_pending
;
1944 int src_out_of_asoc_ok
;
1945 struct sctp_transport
*new_transport
;
1947 /* SCTP AUTH: list of the endpoint shared keys. These
1948 * keys are provided out of band by the user applicaton
1949 * and can't change during the lifetime of the association
1951 struct list_head endpoint_shared_keys
;
1954 * The current generated assocaition shared key (secret)
1956 struct sctp_auth_bytes
*asoc_shared_key
;
1958 /* SCTP AUTH: hmac id of the first peer requested algorithm
1961 __u16 default_hmac_id
;
1963 __u16 active_key_id
;
1965 __u8 need_ecne
:1, /* Need to send an ECNE Chunk? */
1966 temp
:1; /* Is it a temporary association? */
1970 /* An eyecatcher for determining if we are really looking at an
1971 * association data structure.
1974 SCTP_ASSOC_EYECATCHER
= 0xa550c123,
1977 /* Recover the outter association structure. */
1978 static inline struct sctp_association
*sctp_assoc(struct sctp_ep_common
*base
)
1980 struct sctp_association
*asoc
;
1982 asoc
= container_of(base
, struct sctp_association
, base
);
1986 /* These are function signatures for manipulating associations. */
1989 struct sctp_association
*
1990 sctp_association_new(const struct sctp_endpoint
*, const struct sock
*,
1991 sctp_scope_t scope
, gfp_t gfp
);
1992 void sctp_association_free(struct sctp_association
*);
1993 void sctp_association_put(struct sctp_association
*);
1994 void sctp_association_hold(struct sctp_association
*);
1996 struct sctp_transport
*sctp_assoc_choose_alter_transport(
1997 struct sctp_association
*, struct sctp_transport
*);
1998 void sctp_assoc_update_retran_path(struct sctp_association
*);
1999 struct sctp_transport
*sctp_assoc_lookup_paddr(const struct sctp_association
*,
2000 const union sctp_addr
*);
2001 int sctp_assoc_lookup_laddr(struct sctp_association
*asoc
,
2002 const union sctp_addr
*laddr
);
2003 struct sctp_transport
*sctp_assoc_add_peer(struct sctp_association
*,
2004 const union sctp_addr
*address
,
2006 const int peer_state
);
2007 void sctp_assoc_del_peer(struct sctp_association
*asoc
,
2008 const union sctp_addr
*addr
);
2009 void sctp_assoc_rm_peer(struct sctp_association
*asoc
,
2010 struct sctp_transport
*peer
);
2011 void sctp_assoc_control_transport(struct sctp_association
*,
2012 struct sctp_transport
*,
2013 sctp_transport_cmd_t
, sctp_sn_error_t
);
2014 struct sctp_transport
*sctp_assoc_lookup_tsn(struct sctp_association
*, __u32
);
2015 struct sctp_transport
*sctp_assoc_is_match(struct sctp_association
*,
2016 const union sctp_addr
*,
2017 const union sctp_addr
*);
2018 void sctp_assoc_migrate(struct sctp_association
*, struct sock
*);
2019 void sctp_assoc_update(struct sctp_association
*old
,
2020 struct sctp_association
*new);
2022 __u32
sctp_association_get_next_tsn(struct sctp_association
*);
2024 void sctp_assoc_sync_pmtu(struct sock
*, struct sctp_association
*);
2025 void sctp_assoc_rwnd_increase(struct sctp_association
*, unsigned int);
2026 void sctp_assoc_rwnd_decrease(struct sctp_association
*, unsigned int);
2027 void sctp_assoc_set_primary(struct sctp_association
*,
2028 struct sctp_transport
*);
2029 void sctp_assoc_del_nonprimary_peers(struct sctp_association
*,
2030 struct sctp_transport
*);
2031 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association
*,
2032 sctp_scope_t
, gfp_t
);
2033 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association
*,
2034 struct sctp_cookie
*,
2036 int sctp_assoc_set_id(struct sctp_association
*, gfp_t
);
2037 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association
*asoc
);
2038 struct sctp_chunk
*sctp_assoc_lookup_asconf_ack(
2039 const struct sctp_association
*asoc
,
2041 void sctp_asconf_queue_teardown(struct sctp_association
*asoc
);
2043 int sctp_cmp_addr_exact(const union sctp_addr
*ss1
,
2044 const union sctp_addr
*ss2
);
2045 struct sctp_chunk
*sctp_get_ecne_prepend(struct sctp_association
*asoc
);
2047 /* A convenience structure to parse out SCTP specific CMSGs. */
2048 typedef struct sctp_cmsgs
{
2049 struct sctp_initmsg
*init
;
2050 struct sctp_sndrcvinfo
*info
;
2053 /* Structure for tracking memory objects */
2057 } sctp_dbg_objcnt_entry_t
;
2059 #endif /* __sctp_structs_h__ */