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, see
23 * <http://www.gnu.org/licenses/>.
25 * Please send any bug reports or fixes you make to the
27 * lksctp developers <linux-sctp@vger.kernel.org>
29 * Written or modified by:
30 * Randall Stewart <randall@sctp.chicago.il.us>
31 * Ken Morneau <kmorneau@cisco.com>
32 * Qiaobing Xie <qxie1@email.mot.com>
33 * La Monte H.P. Yarroll <piggy@acm.org>
34 * Karl Knutson <karl@athena.chicago.il.us>
35 * Jon Grimm <jgrimm@us.ibm.com>
36 * Xingang Guo <xingang.guo@intel.com>
37 * Hui Huang <hui.huang@nokia.com>
38 * Sridhar Samudrala <sri@us.ibm.com>
39 * Daisy Chang <daisyc@us.ibm.com>
40 * Dajiang Zhang <dajiang.zhang@nokia.com>
41 * Ardelle Fan <ardelle.fan@intel.com>
42 * Ryan Layer <rmlayer@us.ibm.com>
43 * Anup Pemmaiah <pemmaiah@cc.usu.edu>
44 * Kevin Gao <kevin.gao@intel.com>
47 #ifndef __sctp_structs_h__
48 #define __sctp_structs_h__
50 #include <linux/ktime.h>
51 #include <linux/rhashtable.h>
52 #include <linux/socket.h> /* linux/in.h needs this!! */
53 #include <linux/in.h> /* We get struct sockaddr_in. */
54 #include <linux/in6.h> /* We get struct in6_addr */
55 #include <linux/ipv6.h>
56 #include <asm/param.h> /* We get MAXHOSTNAMELEN. */
57 #include <linux/atomic.h> /* This gets us atomic counters. */
58 #include <linux/skbuff.h> /* We need sk_buff_head. */
59 #include <linux/workqueue.h> /* We need tq_struct. */
60 #include <linux/sctp.h> /* We need sctp* header structs. */
61 #include <net/sctp/auth.h> /* We need auth specific structs */
62 #include <net/ip.h> /* For inet_skb_parm */
64 /* A convenience structure for handling sockaddr structures.
65 * We should wean ourselves off this.
68 struct sockaddr_in v4
;
69 struct sockaddr_in6 v6
;
73 /* Forward declarations for data structures. */
76 struct sctp_association
;
77 struct sctp_transport
;
82 struct sctp_bind_addr
;
84 struct sctp_ep_common
;
89 #include <net/sctp/tsnmap.h>
90 #include <net/sctp/ulpevent.h>
91 #include <net/sctp/ulpqueue.h>
93 /* Structures useful for managing bind/connect. */
95 struct sctp_bind_bucket
{
97 unsigned short fastreuse
;
98 struct hlist_node node
;
99 struct hlist_head owner
;
103 struct sctp_bind_hashbucket
{
105 struct hlist_head chain
;
108 /* Used for hashing all associations. */
109 struct sctp_hashbucket
{
111 struct hlist_head chain
;
112 } __attribute__((__aligned__(8)));
115 /* The SCTP globals structure. */
116 extern struct sctp_globals
{
117 /* This is a list of groups of functions for each address
118 * family that we support.
120 struct list_head address_families
;
122 /* This is the hash of all endpoints. */
123 struct sctp_hashbucket
*ep_hashtable
;
124 /* This is the sctp port control hash. */
125 struct sctp_bind_hashbucket
*port_hashtable
;
126 /* This is the hash of all transports. */
127 struct rhltable transport_hashtable
;
129 /* Sizes of above hashtables. */
133 /* Default initialization values to be applied to new associations. */
135 __u16 max_outstreams
;
137 /* Flag to indicate whether computing and verifying checksum
139 bool checksum_disable
;
142 #define sctp_max_instreams (sctp_globals.max_instreams)
143 #define sctp_max_outstreams (sctp_globals.max_outstreams)
144 #define sctp_address_families (sctp_globals.address_families)
145 #define sctp_ep_hashsize (sctp_globals.ep_hashsize)
146 #define sctp_ep_hashtable (sctp_globals.ep_hashtable)
147 #define sctp_port_hashsize (sctp_globals.port_hashsize)
148 #define sctp_port_hashtable (sctp_globals.port_hashtable)
149 #define sctp_transport_hashtable (sctp_globals.transport_hashtable)
150 #define sctp_checksum_disable (sctp_globals.checksum_disable)
152 /* SCTP Socket type: UDP or TCP style. */
155 SCTP_SOCKET_UDP_HIGH_BANDWIDTH
,
157 } sctp_socket_type_t
;
159 /* Per socket SCTP information. */
161 /* inet_sock has to be the first member of sctp_sock */
162 struct inet_sock inet
;
163 /* What kind of a socket is this? */
164 sctp_socket_type_t type
;
166 /* PF_ family specific functions. */
169 /* Access to HMAC transform. */
170 struct crypto_shash
*hmac
;
173 /* What is our base endpointer? */
174 struct sctp_endpoint
*ep
;
176 struct sctp_bind_bucket
*bind_hash
;
177 /* Various Socket Options. */
178 __u16 default_stream
;
181 __u32 default_context
;
182 __u32 default_timetolive
;
183 __u32 default_rcv_context
;
186 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
187 * the destination address every heartbeat interval. This value
188 * will be inherited by all new associations.
192 /* This is the max_retrans value for new associations. */
195 /* The initial Path MTU to use for new associations. */
198 /* The default SACK delay timeout for new associations. */
202 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
205 struct sctp_initmsg initmsg
;
206 struct sctp_rtoinfo rtoinfo
;
207 struct sctp_paddrparams paddrparam
;
208 struct sctp_event_subscribe subscribe
;
209 struct sctp_assocparams assocparams
;
214 __u32 adaptation_ind
;
222 data_ready_signalled
:1;
225 /* Receive to here while partial delivery is in effect. */
226 struct sk_buff_head pd_lobby
;
228 /* These must be the last fields, as they will skipped on copies,
229 * like on accept and peeloff operations
231 struct list_head auto_asconf_list
;
235 static inline struct sctp_sock
*sctp_sk(const struct sock
*sk
)
237 return (struct sctp_sock
*)sk
;
240 static inline struct sock
*sctp_opt2sk(const struct sctp_sock
*sp
)
242 return (struct sock
*)sp
;
245 #if IS_ENABLED(CONFIG_IPV6)
247 struct sctp_sock sctp
;
248 struct ipv6_pinfo inet6
;
250 #endif /* CONFIG_IPV6 */
253 /* This is our APPLICATION-SPECIFIC state cookie.
254 * THIS IS NOT DICTATED BY THE SPECIFICATION.
256 /* These are the parts of an association which we send in the cookie.
257 * Most of these are straight out of:
258 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
264 /* My : Tag expected in every inbound packet and sent
265 * Verification: in the INIT or INIT ACK chunk.
270 /* Peer's : Tag expected in every outbound packet except
271 * Verification: in the INIT chunk.
276 /* The rest of these are not from the spec, but really need to
280 /* My Tie Tag : Assist in discovering a restarting association. */
283 /* Peer's Tie Tag: Assist in discovering a restarting association. */
286 /* When does this cookie expire? */
289 /* Number of inbound/outbound streams which are set
290 * and negotiated during the INIT process.
292 __u16 sinit_num_ostreams
;
293 __u16 sinit_max_instreams
;
295 /* This is the first sequence number I used. */
298 /* This holds the originating address of the INIT packet. */
299 union sctp_addr peer_addr
;
302 * Include the source port of the INIT-ACK
308 /* Padding for future use */
311 __u32 adaptation_ind
;
313 __u8 auth_random
[sizeof(sctp_paramhdr_t
) + SCTP_AUTH_RANDOM_LENGTH
];
314 __u8 auth_hmacs
[SCTP_AUTH_NUM_HMACS
* sizeof(__u16
) + 2];
315 __u8 auth_chunks
[sizeof(sctp_paramhdr_t
) + SCTP_AUTH_MAX_CHUNKS
];
317 /* This is a shim for my peer's INIT packet, followed by
318 * a copy of the raw address list of the association.
319 * The length of the raw address list is saved in the
320 * raw_addr_list_len field, which will be used at the time when
321 * the association TCB is re-constructed from the cookie.
323 __u32 raw_addr_list_len
;
324 struct sctp_init_chunk peer_init
[0];
328 /* The format of our cookie that we send to our peer. */
329 struct sctp_signed_cookie
{
330 __u8 signature
[SCTP_SECRET_SIZE
];
331 __u32 __pad
; /* force sctp_cookie alignment to 64 bits */
332 struct sctp_cookie c
;
335 /* This is another convenience type to allocate memory for address
336 * params for the maximum size and pass such structures around
339 union sctp_addr_param
{
340 struct sctp_paramhdr p
;
341 struct sctp_ipv4addr_param v4
;
342 struct sctp_ipv6addr_param v6
;
345 /* A convenience type to allow walking through the various
346 * parameters and avoid casting all over the place.
350 struct sctp_paramhdr
*p
;
351 struct sctp_cookie_preserve_param
*life
;
352 struct sctp_hostname_param
*dns
;
353 struct sctp_cookie_param
*cookie
;
354 struct sctp_supported_addrs_param
*sat
;
355 struct sctp_ipv4addr_param
*v4
;
356 struct sctp_ipv6addr_param
*v6
;
357 union sctp_addr_param
*addr
;
358 struct sctp_adaptation_ind_param
*aind
;
359 struct sctp_supported_ext_param
*ext
;
360 struct sctp_random_param
*random
;
361 struct sctp_chunks_param
*chunks
;
362 struct sctp_hmac_algo_param
*hmac_algo
;
363 struct sctp_addip_param
*addip
;
366 /* RFC 2960. Section 3.3.5 Heartbeat.
367 * Heartbeat Information: variable length
368 * The Sender-specific Heartbeat Info field should normally include
369 * information about the sender's current time when this HEARTBEAT
370 * chunk is sent and the destination transport address to which this
371 * HEARTBEAT is sent (see Section 8.3).
373 typedef struct sctp_sender_hb_info
{
374 struct sctp_paramhdr param_hdr
;
375 union sctp_addr daddr
;
376 unsigned long sent_at
;
378 } sctp_sender_hb_info_t
;
380 int sctp_stream_init(struct sctp_stream
*stream
, __u16 outcnt
, __u16 incnt
,
382 void sctp_stream_free(struct sctp_stream
*stream
);
383 void sctp_stream_clear(struct sctp_stream
*stream
);
384 void sctp_stream_update(struct sctp_stream
*stream
, struct sctp_stream
*new);
386 /* What is the current SSN number for this stream? */
387 #define sctp_ssn_peek(stream, type, sid) \
388 ((stream)->type[sid].ssn)
390 /* Return the next SSN number for this stream. */
391 #define sctp_ssn_next(stream, type, sid) \
392 ((stream)->type[sid].ssn++)
394 /* Skip over this ssn and all below. */
395 #define sctp_ssn_skip(stream, type, sid, ssn) \
396 ((stream)->type[sid].ssn = ssn + 1)
399 * Pointers to address related SCTP functions.
400 * (i.e. things that depend on the address family.)
403 int (*sctp_xmit
) (struct sk_buff
*skb
,
404 struct sctp_transport
*);
405 int (*setsockopt
) (struct sock
*sk
,
409 unsigned int optlen
);
410 int (*getsockopt
) (struct sock
*sk
,
415 int (*compat_setsockopt
) (struct sock
*sk
,
419 unsigned int optlen
);
420 int (*compat_getsockopt
) (struct sock
*sk
,
425 void (*get_dst
) (struct sctp_transport
*t
,
426 union sctp_addr
*saddr
,
429 void (*get_saddr
) (struct sctp_sock
*sk
,
430 struct sctp_transport
*t
,
432 void (*copy_addrlist
) (struct list_head
*,
433 struct net_device
*);
434 int (*cmp_addr
) (const union sctp_addr
*addr1
,
435 const union sctp_addr
*addr2
);
436 void (*addr_copy
) (union sctp_addr
*dst
,
437 union sctp_addr
*src
);
438 void (*from_skb
) (union sctp_addr
*,
441 void (*from_sk
) (union sctp_addr
*,
443 void (*from_addr_param
) (union sctp_addr
*,
444 union sctp_addr_param
*,
445 __be16 port
, int iif
);
446 int (*to_addr_param
) (const union sctp_addr
*,
447 union sctp_addr_param
*);
448 int (*addr_valid
) (union sctp_addr
*,
450 const struct sk_buff
*);
451 sctp_scope_t (*scope
) (union sctp_addr
*);
452 void (*inaddr_any
) (union sctp_addr
*, __be16
);
453 int (*is_any
) (const union sctp_addr
*);
454 int (*available
) (union sctp_addr
*,
456 int (*skb_iif
) (const struct sk_buff
*sk
);
457 int (*is_ce
) (const struct sk_buff
*sk
);
458 void (*seq_dump_addr
)(struct seq_file
*seq
,
459 union sctp_addr
*addr
);
460 void (*ecn_capable
)(struct sock
*sk
);
461 __u16 net_header_len
;
463 sa_family_t sa_family
;
464 struct list_head list
;
467 struct sctp_af
*sctp_get_af_specific(sa_family_t
);
468 int sctp_register_af(struct sctp_af
*);
470 /* Protocol family functions. */
472 void (*event_msgname
)(struct sctp_ulpevent
*, char *, int *);
473 void (*skb_msgname
) (struct sk_buff
*, char *, int *);
474 int (*af_supported
) (sa_family_t
, struct sctp_sock
*);
475 int (*cmp_addr
) (const union sctp_addr
*,
476 const union sctp_addr
*,
478 int (*bind_verify
) (struct sctp_sock
*, union sctp_addr
*);
479 int (*send_verify
) (struct sctp_sock
*, union sctp_addr
*);
480 int (*supported_addrs
)(const struct sctp_sock
*, __be16
*);
481 struct sock
*(*create_accept_sk
) (struct sock
*sk
,
482 struct sctp_association
*asoc
,
484 int (*addr_to_user
)(struct sctp_sock
*sk
, union sctp_addr
*addr
);
485 void (*to_sk_saddr
)(union sctp_addr
*, struct sock
*sk
);
486 void (*to_sk_daddr
)(union sctp_addr
*, struct sock
*sk
);
491 /* Structure to track chunk fragments that have been acked, but peer
492 * fragments of the same message have not.
494 struct sctp_datamsg
{
495 /* Chunks waiting to be submitted to lower layer. */
496 struct list_head chunks
;
497 /* Reference counting. */
499 /* When is this message no longer interesting to the peer? */
500 unsigned long expires_at
;
501 /* Did the messenge fail to send? */
504 can_delay
; /* should this message be Nagle delayed */
507 struct sctp_datamsg
*sctp_datamsg_from_user(struct sctp_association
*,
508 struct sctp_sndrcvinfo
*,
510 void sctp_datamsg_free(struct sctp_datamsg
*);
511 void sctp_datamsg_put(struct sctp_datamsg
*);
512 void sctp_chunk_fail(struct sctp_chunk
*, int error
);
513 int sctp_chunk_abandoned(struct sctp_chunk
*);
515 /* RFC2960 1.4 Key Terms
517 * o Chunk: A unit of information within an SCTP packet, consisting of
518 * a chunk header and chunk-specific content.
520 * As a matter of convenience, we remember the SCTP common header for
521 * each chunk as well as a few other header pointers...
524 struct list_head list
;
528 /* How many times this chunk have been sent, for prsctp RTX policy */
531 /* This is our link to the per-transport transmitted list. */
532 struct list_head transmitted_list
;
534 /* This field is used by chunks that hold fragmented data.
535 * For the first fragment this is the list that holds the rest of
536 * fragments. For the remaining fragments, this is the link to the
537 * frag_list maintained in the first fragment.
539 struct list_head frag_list
;
541 /* This points to the sk_buff containing the actual data. */
544 /* In case of GSO packets, this will store the head one */
545 struct sk_buff
*head_skb
;
547 /* These are the SCTP headers by reverse order in a packet.
548 * Note that some of these may happen more than once. In that
549 * case, we point at the "current" one, whatever that means
550 * for that level of header.
553 /* We point this at the FIRST TLV parameter to chunk_hdr. */
554 union sctp_params param_hdr
;
557 struct sctp_datahdr
*data_hdr
;
558 struct sctp_inithdr
*init_hdr
;
559 struct sctp_sackhdr
*sack_hdr
;
560 struct sctp_heartbeathdr
*hb_hdr
;
561 struct sctp_sender_hb_info
*hbs_hdr
;
562 struct sctp_shutdownhdr
*shutdown_hdr
;
563 struct sctp_signed_cookie
*cookie_hdr
;
564 struct sctp_ecnehdr
*ecne_hdr
;
565 struct sctp_cwrhdr
*ecn_cwr_hdr
;
566 struct sctp_errhdr
*err_hdr
;
567 struct sctp_addiphdr
*addip_hdr
;
568 struct sctp_fwdtsn_hdr
*fwdtsn_hdr
;
569 struct sctp_authhdr
*auth_hdr
;
574 struct sctp_chunkhdr
*chunk_hdr
;
575 struct sctphdr
*sctp_hdr
;
577 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
578 struct sctp_sndrcvinfo sinfo
;
580 /* Which association does this belong to? */
581 struct sctp_association
*asoc
;
583 /* What endpoint received this chunk? */
584 struct sctp_ep_common
*rcvr
;
586 /* We fill this in if we are calculating RTT. */
587 unsigned long sent_at
;
589 /* What is the origin IP address for this chunk? */
590 union sctp_addr source
;
591 /* Destination address for this chunk. */
592 union sctp_addr dest
;
594 /* For outbound message, track all fragments for SEND_FAILED. */
595 struct sctp_datamsg
*msg
;
597 /* For an inbound chunk, this tells us where it came from.
598 * For an outbound chunk, it tells us where we'd like it to
599 * go. It is NULL if we have no preference.
601 struct sctp_transport
*transport
;
603 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO
604 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
605 * spec violates the principle premis that all chunks are processed
608 struct sk_buff
*auth_chunk
;
610 #define SCTP_CAN_FRTX 0x0
611 #define SCTP_NEED_FRTX 0x1
612 #define SCTP_DONT_FRTX 0x2
613 __u16 rtt_in_progress
:1, /* This chunk used for RTT calc? */
614 has_tsn
:1, /* Does this chunk have a TSN yet? */
615 has_ssn
:1, /* Does this chunk have a SSN yet? */
616 singleton
:1, /* Only chunk in the packet? */
617 end_of_packet
:1, /* Last chunk in the packet? */
618 ecn_ce_done
:1, /* Have we processed the ECN CE bit? */
619 pdiscard
:1, /* Discard the whole packet now? */
620 tsn_gap_acked
:1, /* Is this chunk acked by a GAP ACK? */
621 data_accepted
:1, /* At least 1 chunk accepted */
622 auth
:1, /* IN: was auth'ed | OUT: needs auth */
623 has_asconf
:1, /* IN: have seen an asconf before */
624 tsn_missing_report
:2, /* Data chunk missing counter. */
625 fast_retransmit
:2; /* Is this chunk fast retransmitted? */
628 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1)
629 void sctp_chunk_hold(struct sctp_chunk
*);
630 void sctp_chunk_put(struct sctp_chunk
*);
631 int sctp_user_addto_chunk(struct sctp_chunk
*chunk
, int len
,
632 struct iov_iter
*from
);
633 void sctp_chunk_free(struct sctp_chunk
*);
634 void *sctp_addto_chunk(struct sctp_chunk
*, int len
, const void *data
);
635 struct sctp_chunk
*sctp_chunkify(struct sk_buff
*,
636 const struct sctp_association
*,
637 struct sock
*, gfp_t gfp
);
638 void sctp_init_addrs(struct sctp_chunk
*, union sctp_addr
*,
640 const union sctp_addr
*sctp_source(const struct sctp_chunk
*chunk
);
643 SCTP_ADDR_NEW
, /* new address added to assoc/ep */
644 SCTP_ADDR_SRC
, /* address can be used as source */
645 SCTP_ADDR_DEL
, /* address about to be deleted */
648 /* This is a structure for holding either an IPv6 or an IPv4 address. */
649 struct sctp_sockaddr_entry
{
650 struct list_head list
;
657 #define SCTP_ADDRESS_TICK_DELAY 500
659 typedef struct sctp_chunk
*(sctp_packet_phandler_t
)(struct sctp_association
*);
661 /* This structure holds lists of chunks as we are assembling for
665 /* These are the SCTP header values (host order) for the packet. */
667 __u16 destination_port
;
670 /* This contains the payload chunks. */
671 struct list_head chunk_list
;
673 /* This is the overhead of the sctp and ip headers. */
675 /* This is the total size of all chunks INCLUDING padding. */
677 /* This is the maximum size this packet may have */
680 /* The packet is destined for this transport address.
681 * The function we finally use to pass down to the next lower
682 * layer lives in the transport structure.
684 struct sctp_transport
*transport
;
686 /* pointer to the auth chunk for this packet */
687 struct sctp_chunk
*auth
;
689 u8 has_cookie_echo
:1, /* This packet contains a COOKIE-ECHO chunk. */
690 has_sack
:1, /* This packet contains a SACK chunk. */
691 has_auth
:1, /* This packet contains an AUTH chunk */
692 has_data
:1, /* This packet contains at least 1 DATA chunk */
693 ipfragok
:1; /* So let ip fragment this packet */
696 void sctp_packet_init(struct sctp_packet
*, struct sctp_transport
*,
697 __u16 sport
, __u16 dport
);
698 void sctp_packet_config(struct sctp_packet
*, __u32 vtag
, int);
699 sctp_xmit_t
sctp_packet_transmit_chunk(struct sctp_packet
*,
700 struct sctp_chunk
*, int, gfp_t
);
701 sctp_xmit_t
sctp_packet_append_chunk(struct sctp_packet
*,
702 struct sctp_chunk
*);
703 int sctp_packet_transmit(struct sctp_packet
*, gfp_t
);
704 void sctp_packet_free(struct sctp_packet
*);
706 static inline int sctp_packet_empty(struct sctp_packet
*packet
)
708 return packet
->size
== packet
->overhead
;
711 /* This represents a remote transport address.
712 * For local transport addresses, we just use union sctp_addr.
714 * RFC2960 Section 1.4 Key Terms
716 * o Transport address: A Transport Address is traditionally defined
717 * by Network Layer address, Transport Layer protocol and Transport
718 * Layer port number. In the case of SCTP running over IP, a
719 * transport address is defined by the combination of an IP address
720 * and an SCTP port number (where SCTP is the Transport protocol).
722 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
724 * o The sender keeps a separate congestion control parameter set for
725 * each of the destination addresses it can send to (not each
726 * source-destination pair but for each destination). The parameters
727 * should decay if the address is not used for a long enough time
731 struct sctp_transport
{
732 /* A list of transports. */
733 struct list_head transports
;
734 struct rhlist_head node
;
736 /* Reference counting. */
738 /* RTO-Pending : A flag used to track if one of the DATA
739 * chunks sent to this address is currently being
740 * used to compute a RTT. If this flag is 0,
741 * the next DATA chunk sent to this destination
742 * should be used to compute a RTT and this flag
743 * should be set. Every time the RTT
744 * calculation completes (i.e. the DATA chunk
745 * is SACK'd) clear this flag.
750 * hb_sent : a flag that signals that we have a pending
755 /* Is the Path MTU update pending on this tranport */
758 dst_pending_confirm
:1, /* need to confirm neighbour */
760 /* Has this transport moved the ctsn since we last sacked */
766 /* This is the peer's IP address and port. */
767 union sctp_addr ipaddr
;
769 /* These are the functions we call to handle LLP stuff. */
770 struct sctp_af
*af_specific
;
772 /* Which association do we belong to? */
773 struct sctp_association
*asoc
;
777 * 12.3 Per Transport Address Data
779 * For each destination transport address in the peer's
780 * address list derived from the INIT or INIT ACK chunk, a
781 * number of data elements needs to be maintained including:
783 /* RTO : The current retransmission timeout value. */
786 __u32 rtt
; /* This is the most recent RTT. */
788 /* RTTVAR : The current RTT variation. */
791 /* SRTT : The current smoothed round trip time. */
795 * These are the congestion stats.
797 /* cwnd : The current congestion window. */
798 __u32 cwnd
; /* This is the actual cwnd. */
800 /* ssthresh : The current slow start threshold value. */
803 /* partial : The tracking method for increase of cwnd when in
804 * bytes acked : congestion avoidance mode (see Section 6.2.2)
806 __u32 partial_bytes_acked
;
808 /* Data that has been sent, but not acknowledged. */
811 __u32 burst_limited
; /* Holds old cwnd when max.burst is applied */
814 struct dst_entry
*dst
;
815 /* Source address. */
816 union sctp_addr saddr
;
818 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
819 * the destination address every heartbeat interval.
821 unsigned long hbinterval
;
823 /* SACK delay timeout */
824 unsigned long sackdelay
;
827 /* When was the last time that we heard from this transport? We use
828 * this to pick new active and retran paths.
830 ktime_t last_time_heard
;
832 /* When was the last time that we sent a chunk using this
833 * transport? We use this to check for idle transports
835 unsigned long last_time_sent
;
837 /* Last time(in jiffies) when cwnd is reduced due to the congestion
838 * indication based on ECNE chunk.
840 unsigned long last_time_ecne_reduced
;
842 /* This is the max_retrans value for the transport and will
843 * be initialized from the assocs value. This can be changed
844 * using the SCTP_SET_PEER_ADDR_PARAMS socket option.
848 /* This is the partially failed retrans value for the transport
849 * and will be initialized from the assocs value. This can be changed
850 * using the SCTP_PEER_ADDR_THLDS socket option
853 /* PMTU : The current known path MTU. */
856 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
859 /* The number of times INIT has been sent on this transport. */
862 /* state : The current state of this destination,
863 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
867 /* These are the error stats for this destination. */
869 /* Error count : The current error count for this destination. */
870 unsigned short error_count
;
872 /* Per : A timer used by each destination.
876 * [Everywhere else in the text this is called T3-rtx. -ed]
878 struct timer_list T3_rtx_timer
;
880 /* Heartbeat timer is per destination. */
881 struct timer_list hb_timer
;
883 /* Timer to handle ICMP proto unreachable envets */
884 struct timer_list proto_unreach_timer
;
886 /* Timer to handler reconf chunk rtx */
887 struct timer_list reconf_timer
;
889 /* Since we're using per-destination retransmission timers
890 * (see above), we're also using per-destination "transmitted"
891 * queues. This probably ought to be a private struct
892 * accessible only within the outqueue, but it's not, yet.
894 struct list_head transmitted
;
896 /* We build bundle-able packets for this transport here. */
897 struct sctp_packet packet
;
899 /* This is the list of transports that have chunks to send. */
900 struct list_head send_ready
;
902 /* State information saved for SFR_CACC algorithm. The key
903 * idea in SFR_CACC is to maintain state at the sender on a
904 * per-destination basis when a changeover happens.
905 * char changeover_active;
906 * char cycling_changeover;
907 * __u32 next_tsn_at_change;
908 * char cacc_saw_newack;
911 /* An unsigned integer, which stores the next TSN to be
912 * used by the sender, at the moment of changeover.
914 __u32 next_tsn_at_change
;
916 /* A flag which indicates the occurrence of a changeover */
917 char changeover_active
;
919 /* A flag which indicates whether the change of primary is
920 * the first switch to this destination address during an
923 char cycling_changeover
;
925 /* A temporary flag, which is used during the processing of
926 * a SACK to estimate the causative TSN(s)'s group.
928 char cacc_saw_newack
;
931 /* 64-bit random number sent with heartbeat. */
937 struct sctp_transport
*sctp_transport_new(struct net
*, const union sctp_addr
*,
939 void sctp_transport_set_owner(struct sctp_transport
*,
940 struct sctp_association
*);
941 void sctp_transport_route(struct sctp_transport
*, union sctp_addr
*,
943 void sctp_transport_pmtu(struct sctp_transport
*, struct sock
*sk
);
944 void sctp_transport_free(struct sctp_transport
*);
945 void sctp_transport_reset_t3_rtx(struct sctp_transport
*);
946 void sctp_transport_reset_hb_timer(struct sctp_transport
*);
947 void sctp_transport_reset_reconf_timer(struct sctp_transport
*transport
);
948 int sctp_transport_hold(struct sctp_transport
*);
949 void sctp_transport_put(struct sctp_transport
*);
950 void sctp_transport_update_rto(struct sctp_transport
*, __u32
);
951 void sctp_transport_raise_cwnd(struct sctp_transport
*, __u32
, __u32
);
952 void sctp_transport_lower_cwnd(struct sctp_transport
*, sctp_lower_cwnd_t
);
953 void sctp_transport_burst_limited(struct sctp_transport
*);
954 void sctp_transport_burst_reset(struct sctp_transport
*);
955 unsigned long sctp_transport_timeout(struct sctp_transport
*);
956 void sctp_transport_reset(struct sctp_transport
*t
);
957 void sctp_transport_update_pmtu(struct sctp_transport
*t
, u32 pmtu
);
958 void sctp_transport_immediate_rtx(struct sctp_transport
*);
959 void sctp_transport_dst_release(struct sctp_transport
*t
);
960 void sctp_transport_dst_confirm(struct sctp_transport
*t
);
963 /* This is the structure we use to queue packets as they come into
964 * SCTP. We write packets to it and read chunks from it.
967 /* This is actually a queue of sctp_chunk each
968 * containing a partially decoded packet.
970 struct list_head in_chunk_list
;
971 /* This is the packet which is currently off the in queue and is
972 * being worked on through the inbound chunk processing.
974 struct sctp_chunk
*in_progress
;
976 /* This is the delayed task to finish delivering inbound
979 struct work_struct immediate
;
982 void sctp_inq_init(struct sctp_inq
*);
983 void sctp_inq_free(struct sctp_inq
*);
984 void sctp_inq_push(struct sctp_inq
*, struct sctp_chunk
*packet
);
985 struct sctp_chunk
*sctp_inq_pop(struct sctp_inq
*);
986 struct sctp_chunkhdr
*sctp_inq_peek(struct sctp_inq
*);
987 void sctp_inq_set_th_handler(struct sctp_inq
*, work_func_t
);
989 /* This is the structure we use to hold outbound chunks. You push
990 * chunks in and they automatically pop out the other end as bundled
991 * packets (it calls (*output_handler)()).
993 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
994 * and 8.2 of the v13 draft.
996 * It handles retransmissions. The connection to the timeout portion
997 * of the state machine is through sctp_..._timeout() and timeout_handler.
999 * If you feed it SACKs, it will eat them.
1001 * If you give it big chunks, it will fragment them.
1003 * It assigns TSN's to data chunks. This happens at the last possible
1004 * instant before transmission.
1006 * When free()'d, it empties itself out via output_handler().
1009 struct sctp_association
*asoc
;
1011 /* Data pending that has never been transmitted. */
1012 struct list_head out_chunk_list
;
1014 unsigned int out_qlen
; /* Total length of queued data chunks. */
1016 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1019 /* These are control chunks we want to send. */
1020 struct list_head control_chunk_list
;
1022 /* These are chunks that have been sacked but are above the
1023 * CTSN, or cumulative tsn ack point.
1025 struct list_head sacked
;
1027 /* Put chunks on this list to schedule them for
1030 struct list_head retransmit
;
1032 /* Put chunks on this list to save them for FWD TSN processing as
1033 * they were abandoned.
1035 struct list_head abandoned
;
1037 /* How many unackd bytes do we have in-flight? */
1038 __u32 outstanding_bytes
;
1040 /* Are we doing fast-rtx on this queue */
1047 void sctp_outq_init(struct sctp_association
*, struct sctp_outq
*);
1048 void sctp_outq_teardown(struct sctp_outq
*);
1049 void sctp_outq_free(struct sctp_outq
*);
1050 void sctp_outq_tail(struct sctp_outq
*, struct sctp_chunk
*chunk
, gfp_t
);
1051 int sctp_outq_sack(struct sctp_outq
*, struct sctp_chunk
*);
1052 int sctp_outq_is_empty(const struct sctp_outq
*);
1053 void sctp_outq_restart(struct sctp_outq
*);
1055 void sctp_retransmit(struct sctp_outq
*, struct sctp_transport
*,
1056 sctp_retransmit_reason_t
);
1057 void sctp_retransmit_mark(struct sctp_outq
*, struct sctp_transport
*, __u8
);
1058 void sctp_outq_uncork(struct sctp_outq
*, gfp_t gfp
);
1059 void sctp_prsctp_prune(struct sctp_association
*asoc
,
1060 struct sctp_sndrcvinfo
*sinfo
, int msg_len
);
1061 /* Uncork and flush an outqueue. */
1062 static inline void sctp_outq_cork(struct sctp_outq
*q
)
1067 /* SCTP skb control block.
1068 * sctp_input_cb is currently used on rx and sock rx queue
1070 struct sctp_input_cb
{
1072 struct inet_skb_parm h4
;
1073 #if IS_ENABLED(CONFIG_IPV6)
1074 struct inet6_skb_parm h6
;
1077 struct sctp_chunk
*chunk
;
1080 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0]))
1082 static inline const struct sk_buff
*sctp_gso_headskb(const struct sk_buff
*skb
)
1084 const struct sctp_chunk
*chunk
= SCTP_INPUT_CB(skb
)->chunk
;
1086 return chunk
->head_skb
? : skb
;
1089 /* These bind address data fields common between endpoints and associations */
1090 struct sctp_bind_addr
{
1092 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1094 * SCTP Port: The local SCTP port number the endpoint is
1099 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1101 * Address List: The list of IP addresses that this instance
1102 * has bound. This information is passed to one's
1103 * peer(s) in INIT and INIT ACK chunks.
1105 struct list_head address_list
;
1108 void sctp_bind_addr_init(struct sctp_bind_addr
*, __u16 port
);
1109 void sctp_bind_addr_free(struct sctp_bind_addr
*);
1110 int sctp_bind_addr_copy(struct net
*net
, struct sctp_bind_addr
*dest
,
1111 const struct sctp_bind_addr
*src
,
1112 sctp_scope_t scope
, gfp_t gfp
,
1114 int sctp_bind_addr_dup(struct sctp_bind_addr
*dest
,
1115 const struct sctp_bind_addr
*src
,
1117 int sctp_add_bind_addr(struct sctp_bind_addr
*, union sctp_addr
*,
1118 int new_size
, __u8 addr_state
, gfp_t gfp
);
1119 int sctp_del_bind_addr(struct sctp_bind_addr
*, union sctp_addr
*);
1120 int sctp_bind_addr_match(struct sctp_bind_addr
*, const union sctp_addr
*,
1121 struct sctp_sock
*);
1122 int sctp_bind_addr_conflict(struct sctp_bind_addr
*, const union sctp_addr
*,
1123 struct sctp_sock
*, struct sctp_sock
*);
1124 int sctp_bind_addr_state(const struct sctp_bind_addr
*bp
,
1125 const union sctp_addr
*addr
);
1126 union sctp_addr
*sctp_find_unmatch_addr(struct sctp_bind_addr
*bp
,
1127 const union sctp_addr
*addrs
,
1129 struct sctp_sock
*opt
);
1130 union sctp_params
sctp_bind_addrs_to_raw(const struct sctp_bind_addr
*bp
,
1133 int sctp_raw_to_bind_addrs(struct sctp_bind_addr
*bp
, __u8
*raw
, int len
,
1134 __u16 port
, gfp_t gfp
);
1136 sctp_scope_t
sctp_scope(const union sctp_addr
*);
1137 int sctp_in_scope(struct net
*net
, const union sctp_addr
*addr
, const sctp_scope_t scope
);
1138 int sctp_is_any(struct sock
*sk
, const union sctp_addr
*addr
);
1139 int sctp_is_ep_boundall(struct sock
*sk
);
1142 /* What type of endpoint? */
1144 SCTP_EP_TYPE_SOCKET
,
1145 SCTP_EP_TYPE_ASSOCIATION
,
1146 } sctp_endpoint_type_t
;
1149 * A common base class to bridge the implmentation view of a
1150 * socket (usually listening) endpoint versus an association's
1152 * This common structure is useful for several purposes:
1153 * 1) Common interface for lookup routines.
1154 * a) Subfunctions work for either endpoint or association
1155 * b) Single interface to lookup allows hiding the lookup lock rather
1156 * than acquiring it externally.
1157 * 2) Common interface for the inbound chunk handling/state machine.
1158 * 3) Common object handling routines for reference counting, etc.
1159 * 4) Disentangle association lookup from endpoint lookup, where we
1160 * do not have to find our endpoint to find our association.
1164 struct sctp_ep_common
{
1165 /* Fields to help us manage our entries in the hash tables. */
1166 struct hlist_node node
;
1169 /* Runtime type information. What kind of endpoint is this? */
1170 sctp_endpoint_type_t type
;
1172 /* Some fields to help us manage this object.
1173 * refcnt - Reference count access to this object.
1174 * dead - Do not attempt to use this object.
1179 /* What socket does this endpoint belong to? */
1182 /* This is where we receive inbound chunks. */
1183 struct sctp_inq inqueue
;
1185 /* This substructure includes the defining parameters of the
1187 * bind_addr.port is our shared port number.
1188 * bind_addr.address_list is our set of local IP addresses.
1190 struct sctp_bind_addr bind_addr
;
1194 /* RFC Section 1.4 Key Terms
1196 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1197 * multi-homed host, an SCTP endpoint is represented to its peers as a
1198 * combination of a set of eligible destination transport addresses to
1199 * which SCTP packets can be sent and a set of eligible source
1200 * transport addresses from which SCTP packets can be received.
1201 * All transport addresses used by an SCTP endpoint must use the
1202 * same port number, but can use multiple IP addresses. A transport
1203 * address used by an SCTP endpoint must not be used by another
1204 * SCTP endpoint. In other words, a transport address is unique
1205 * to an SCTP endpoint.
1207 * From an implementation perspective, each socket has one of these.
1208 * A TCP-style socket will have exactly one association on one of
1209 * these. An UDP-style socket will have multiple associations hanging
1213 struct sctp_endpoint
{
1214 /* Common substructure for endpoint and association. */
1215 struct sctp_ep_common base
;
1217 /* Associations: A list of current associations and mappings
1218 * to the data consumers for each association. This
1219 * may be in the form of a hash table or other
1220 * implementation dependent structure. The data
1221 * consumers may be process identification
1222 * information such as file descriptors, named pipe
1223 * pointer, or table pointers dependent on how SCTP
1226 /* This is really a list of struct sctp_association entries. */
1227 struct list_head asocs
;
1229 /* Secret Key: A secret key used by this endpoint to compute
1230 * the MAC. This SHOULD be a cryptographic quality
1231 * random number with a sufficient length.
1232 * Discussion in [RFC1750] can be helpful in
1233 * selection of the key.
1235 __u8 secret_key
[SCTP_SECRET_SIZE
];
1237 /* digest: This is a digest of the sctp cookie. This field is
1238 * only used on the receive path when we try to validate
1239 * that the cookie has not been tampered with. We put
1240 * this here so we pre-allocate this once and can re-use
1245 /* sendbuf acct. policy. */
1246 __u32 sndbuf_policy
;
1248 /* rcvbuf acct. policy. */
1249 __u32 rcvbuf_policy
;
1251 /* SCTP AUTH: array of the HMACs that will be allocated
1252 * we need this per association so that we don't serialize
1254 struct crypto_shash
**auth_hmacs
;
1256 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1257 struct sctp_hmac_algo_param
*auth_hmacs_list
;
1259 /* SCTP-AUTH: chunks to authenticate encoded into parameter */
1260 struct sctp_chunks_param
*auth_chunk_list
;
1262 /* SCTP-AUTH: endpoint shared keys */
1263 struct list_head endpoint_shared_keys
;
1264 __u16 active_key_id
;
1269 __u8 strreset_enable
;
1272 /* Recover the outter endpoint structure. */
1273 static inline struct sctp_endpoint
*sctp_ep(struct sctp_ep_common
*base
)
1275 struct sctp_endpoint
*ep
;
1277 ep
= container_of(base
, struct sctp_endpoint
, base
);
1281 /* These are function signatures for manipulating endpoints. */
1282 struct sctp_endpoint
*sctp_endpoint_new(struct sock
*, gfp_t
);
1283 void sctp_endpoint_free(struct sctp_endpoint
*);
1284 void sctp_endpoint_put(struct sctp_endpoint
*);
1285 void sctp_endpoint_hold(struct sctp_endpoint
*);
1286 void sctp_endpoint_add_asoc(struct sctp_endpoint
*, struct sctp_association
*);
1287 struct sctp_association
*sctp_endpoint_lookup_assoc(
1288 const struct sctp_endpoint
*ep
,
1289 const union sctp_addr
*paddr
,
1290 struct sctp_transport
**);
1291 int sctp_endpoint_is_peeled_off(struct sctp_endpoint
*,
1292 const union sctp_addr
*);
1293 struct sctp_endpoint
*sctp_endpoint_is_match(struct sctp_endpoint
*,
1294 struct net
*, const union sctp_addr
*);
1295 int sctp_has_association(struct net
*net
, const union sctp_addr
*laddr
,
1296 const union sctp_addr
*paddr
);
1298 int sctp_verify_init(struct net
*net
, const struct sctp_endpoint
*ep
,
1299 const struct sctp_association
*asoc
,
1300 sctp_cid_t
, sctp_init_chunk_t
*peer_init
,
1301 struct sctp_chunk
*chunk
, struct sctp_chunk
**err_chunk
);
1302 int sctp_process_init(struct sctp_association
*, struct sctp_chunk
*chunk
,
1303 const union sctp_addr
*peer
,
1304 sctp_init_chunk_t
*init
, gfp_t gfp
);
1305 __u32
sctp_generate_tag(const struct sctp_endpoint
*);
1306 __u32
sctp_generate_tsn(const struct sctp_endpoint
*);
1308 struct sctp_inithdr_host
{
1311 __u16 num_outbound_streams
;
1312 __u16 num_inbound_streams
;
1316 struct sctp_stream_out
{
1319 __u64 abandoned_unsent
[SCTP_PR_INDEX(MAX
) + 1];
1320 __u64 abandoned_sent
[SCTP_PR_INDEX(MAX
) + 1];
1323 struct sctp_stream_in
{
1327 struct sctp_stream
{
1328 struct sctp_stream_out
*out
;
1329 struct sctp_stream_in
*in
;
1334 #define SCTP_STREAM_CLOSED 0x00
1335 #define SCTP_STREAM_OPEN 0x01
1337 /* SCTP_GET_ASSOC_STATS counters */
1338 struct sctp_priv_assoc_stats
{
1339 /* Maximum observed rto in the association during subsequent
1340 * observations. Value is set to 0 if no RTO measurement took place
1341 * The transport where the max_rto was observed is returned in
1344 struct sockaddr_storage obs_rto_ipaddr
;
1346 /* Total In and Out SACKs received and sent */
1349 /* Total In and Out packets received and sent */
1352 /* Total retransmitted chunks */
1354 /* TSN received > next expected */
1356 /* Duplicate Chunks received */
1358 /* Gap Ack Blocks received */
1360 /* Unordered data chunks sent and received */
1363 /* Ordered data chunks sent and received */
1366 /* Control chunks sent and received */
1373 * 12. Recommended Transmission Control Block (TCB) Parameters
1375 * This section details a recommended set of parameters that should
1376 * be contained within the TCB for an implementation. This section is
1377 * for illustrative purposes and should not be deemed as requirements
1378 * on an implementation or as an exhaustive list of all parameters
1379 * inside an SCTP TCB. Each implementation may need its own additional
1380 * parameters for optimization.
1384 /* Here we have information about each individual association. */
1385 struct sctp_association
{
1387 /* A base structure common to endpoint and association.
1388 * In this context, it represents the associations's view
1389 * of the local endpoint of the association.
1391 struct sctp_ep_common base
;
1393 /* Associations on the same socket. */
1394 struct list_head asocs
;
1396 /* association id. */
1397 sctp_assoc_t assoc_id
;
1399 /* This is our parent endpoint. */
1400 struct sctp_endpoint
*ep
;
1402 /* These are those association elements needed in the cookie. */
1403 struct sctp_cookie c
;
1405 /* This is all information about our peer. */
1407 /* transport_addr_list
1409 * Peer : A list of SCTP transport addresses that the
1410 * Transport : peer is bound to. This information is derived
1411 * Address : from the INIT or INIT ACK and is used to
1412 * List : associate an inbound packet with a given
1413 * : association. Normally this information is
1414 * : hashed or keyed for quick lookup and access
1416 * : The list is also initialized with the list
1417 * : of addresses passed with the sctp_connectx()
1420 * It is a list of SCTP_transport's.
1422 struct list_head transport_addr_list
;
1426 * Peer Rwnd : Current calculated value of the peer's rwnd.
1432 * Peer : A count of the number of peer addresses
1433 * Transport : in the Peer Transport Address List.
1437 __u16 transport_count
;
1440 * The transport layer port number.
1446 * Primary : This is the current primary destination
1447 * Path : transport address of the peer endpoint. It
1448 * : may also specify a source transport address
1449 * : on this endpoint.
1451 * All of these paths live on transport_addr_list.
1453 * At the bakeoffs, we discovered that the intent of
1454 * primaryPath is that it only changes when the ULP
1455 * asks to have it changed. We add the activePath to
1456 * designate the connection we are currently using to
1457 * transmit new data and most control chunks.
1459 struct sctp_transport
*primary_path
;
1461 /* Cache the primary path address here, when we
1462 * need a an address for msg_name.
1464 union sctp_addr primary_addr
;
1467 * The path that we are currently using to
1468 * transmit new data and most control chunks.
1470 struct sctp_transport
*active_path
;
1474 * RFC2960 6.4 Multi-homed SCTP Endpoints
1476 * Furthermore, when its peer is multi-homed, an
1477 * endpoint SHOULD try to retransmit a chunk to an
1478 * active destination transport address that is
1479 * different from the last destination address to
1480 * which the DATA chunk was sent.
1482 struct sctp_transport
*retran_path
;
1484 /* Pointer to last transport I have sent on. */
1485 struct sctp_transport
*last_sent_to
;
1487 /* This is the last transport I have received DATA on. */
1488 struct sctp_transport
*last_data_from
;
1491 * Mapping An array of bits or bytes indicating which out of
1492 * Array order TSN's have been received (relative to the
1493 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1494 * order packets have been received, this array
1495 * will be set to all zero. This structure may be
1496 * in the form of a circular buffer or bit array.
1498 * Last Rcvd : This is the last TSN received in
1499 * TSN : sequence. This value is set initially by
1500 * : taking the peer's Initial TSN, received in
1501 * : the INIT or INIT ACK chunk, and subtracting
1504 * Throughout most of the specification this is called the
1505 * "Cumulative TSN ACK Point". In this case, we
1506 * ignore the advice in 12.2 in favour of the term
1507 * used in the bulk of the text. This value is hidden
1508 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1510 struct sctp_tsnmap tsn_map
;
1512 /* This mask is used to disable sending the ASCONF chunk
1513 * with specified parameter to peer.
1515 __be16 addip_disabled_mask
;
1517 /* These are capabilities which our peer advertised. */
1518 __u8 ecn_capable
:1, /* Can peer do ECN? */
1519 ipv4_address
:1, /* Peer understands IPv4 addresses? */
1520 ipv6_address
:1, /* Peer understands IPv6 addresses? */
1521 hostname_address
:1, /* Peer understands DNS addresses? */
1522 asconf_capable
:1, /* Does peer support ADDIP? */
1523 prsctp_capable
:1, /* Can peer do PR-SCTP? */
1524 reconf_capable
:1, /* Can peer do RE-CONFIG? */
1525 auth_capable
:1; /* Is peer doing SCTP-AUTH? */
1527 /* sack_needed : This flag indicates if the next received
1528 * : packet is to be responded to with a
1529 * : SACK. This is initialized to 0. When a packet
1530 * : is received sack_cnt is incremented. If this value
1531 * : reaches 2 or more, a SACK is sent and the
1532 * : value is reset to 0. Note: This is used only
1533 * : when no DATA chunks are received out of
1534 * : order. When DATA chunks are out of order,
1535 * : SACK's are not delayed (see Section 6).
1537 __u8 sack_needed
:1, /* Do we need to sack the peer? */
1539 zero_window_announced
:1;
1542 __u32 adaptation_ind
; /* Adaptation Code point. */
1544 struct sctp_inithdr_host i
;
1548 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1549 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1550 * Initial TSN Value minus 1
1554 /* SCTP-AUTH: We need to know pears random number, hmac list
1555 * and authenticated chunk list. All that is part of the
1556 * cookie and these are just pointers to those locations
1558 sctp_random_param_t
*peer_random
;
1559 sctp_chunks_param_t
*peer_chunks
;
1560 sctp_hmac_algo_param_t
*peer_hmacs
;
1563 /* State : A state variable indicating what state the
1564 * : association is in, i.e. COOKIE-WAIT,
1565 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1566 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1568 * Note: No "CLOSED" state is illustrated since if a
1569 * association is "CLOSED" its TCB SHOULD be removed.
1571 * In this implementation we DO have a CLOSED
1572 * state which is used during initiation and shutdown.
1574 * State takes values from SCTP_STATE_*.
1578 /* Overall : The overall association error count.
1579 * Error Count : [Clear this any time I get something.]
1581 int overall_error_count
;
1583 /* The cookie life I award for any cookie. */
1584 ktime_t cookie_life
;
1586 /* These are the association's initial, max, and min RTO values.
1587 * These values will be initialized by system defaults, but can
1588 * be modified via the SCTP_RTOINFO socket option.
1590 unsigned long rto_initial
;
1591 unsigned long rto_max
;
1592 unsigned long rto_min
;
1594 /* Maximum number of new data packets that can be sent in a burst. */
1597 /* This is the max_retrans value for the association. This value will
1598 * be initialized initialized from system defaults, but can be
1599 * modified by the SCTP_ASSOCINFO socket option.
1603 /* This is the partially failed retrans value for the transport
1604 * and will be initialized from the assocs value. This can be
1605 * changed using the SCTP_PEER_ADDR_THLDS socket option
1609 /* Maximum number of times the endpoint will retransmit INIT */
1610 __u16 max_init_attempts
;
1612 /* How many times have we resent an INIT? */
1615 /* The largest timeout or RTO value to use in attempting an INIT */
1616 unsigned long max_init_timeo
;
1618 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1619 * the destination address every heartbeat interval. This value
1620 * will be inherited by all new transports.
1622 unsigned long hbinterval
;
1624 /* This is the max_retrans value for new transports in the
1629 /* Flag that path mtu update is pending */
1632 /* Association : The smallest PMTU discovered for all of the
1633 * PMTU : peer's transport addresses.
1637 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1641 /* SACK delay timeout */
1642 unsigned long sackdelay
;
1644 unsigned long timeouts
[SCTP_NUM_TIMEOUT_TYPES
];
1645 struct timer_list timers
[SCTP_NUM_TIMEOUT_TYPES
];
1647 /* Transport to which SHUTDOWN chunk was last sent. */
1648 struct sctp_transport
*shutdown_last_sent_to
;
1650 /* Transport to which INIT chunk was last sent. */
1651 struct sctp_transport
*init_last_sent_to
;
1653 /* How many times have we resent a SHUTDOWN */
1654 int shutdown_retries
;
1656 /* Next TSN : The next TSN number to be assigned to a new
1657 * : DATA chunk. This is sent in the INIT or INIT
1658 * : ACK chunk to the peer and incremented each
1659 * : time a DATA chunk is assigned a TSN
1660 * : (normally just prior to transmit or during
1666 * Last Rcvd : This is the last TSN received in sequence. This value
1667 * TSN : is set initially by taking the peer's Initial TSN,
1668 * : received in the INIT or INIT ACK chunk, and
1669 * : subtracting one from it.
1671 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1674 __u32 ctsn_ack_point
;
1676 /* PR-SCTP Advanced.Peer.Ack.Point */
1677 __u32 adv_peer_ack_point
;
1679 /* Highest TSN that is acknowledged by incoming SACKs. */
1680 __u32 highest_sacked
;
1682 /* TSN marking the fast recovery exit point */
1683 __u32 fast_recovery_exit
;
1685 /* Flag to track the current fast recovery state */
1688 /* The number of unacknowledged data chunks. Reported through
1689 * the SCTP_STATUS sockopt.
1693 /* The total number of data chunks that we've had to retransmit
1694 * as the result of a T3 timer expiration
1696 __u32 rtx_data_chunks
;
1698 /* This is the association's receive buffer space. This value is used
1699 * to set a_rwnd field in an INIT or a SACK chunk.
1703 /* This is the last advertised value of rwnd over a SACK chunk. */
1706 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1707 * to slop over a maximum of the association's frag_point.
1711 /* Keeps treack of rwnd pressure. This happens when we have
1712 * a window, but not recevie buffer (i.e small packets). This one
1713 * is releases slowly (1 PMTU at a time ).
1717 /* This is the sndbuf size in use for the association.
1718 * This corresponds to the sndbuf size for the association,
1719 * as specified in the sk->sndbuf.
1723 /* This is the amount of memory that this association has allocated
1724 * in the receive path at any given time.
1726 atomic_t rmem_alloc
;
1728 /* This is the wait queue head for send requests waiting on
1729 * the association sndbuf space.
1731 wait_queue_head_t wait
;
1733 /* The message size at which SCTP fragmentation will occur. */
1737 /* Counter used to count INIT errors. */
1738 int init_err_counter
;
1740 /* Count the number of INIT cycles (for doubling timeout). */
1743 /* Default send parameters. */
1744 __u16 default_stream
;
1745 __u16 default_flags
;
1747 __u32 default_context
;
1748 __u32 default_timetolive
;
1750 /* Default receive parameters */
1751 __u32 default_rcv_context
;
1754 struct sctp_stream stream
;
1756 /* All outbound chunks go through this structure. */
1757 struct sctp_outq outqueue
;
1759 /* A smart pipe that will handle reordering and fragmentation,
1760 * as well as handle passing events up to the ULP.
1762 struct sctp_ulpq ulpq
;
1764 /* Last TSN that caused an ECNE Chunk to be sent. */
1765 __u32 last_ecne_tsn
;
1767 /* Last TSN that caused a CWR Chunk to be sent. */
1770 /* How many duplicated TSNs have we seen? */
1773 /* These are to support
1774 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1775 * and Enforcement of Flow and Message Limits"
1776 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1777 * or "ADDIP" for short.
1782 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1784 * R1) One and only one ASCONF Chunk MAY be in transit and
1785 * unacknowledged at any one time. If a sender, after sending
1786 * an ASCONF chunk, decides it needs to transfer another
1787 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1788 * returns from the previous ASCONF Chunk before sending a
1789 * subsequent ASCONF. Note this restriction binds each side,
1790 * so at any time two ASCONF may be in-transit on any given
1791 * association (one sent from each endpoint).
1793 * [This is our one-and-only-one ASCONF in flight. If we do
1794 * not have an ASCONF in flight, this is NULL.]
1796 struct sctp_chunk
*addip_last_asconf
;
1798 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
1800 * This is needed to implement itmes E1 - E4 of the updated
1801 * spec. Here is the justification:
1803 * Since the peer may bundle multiple ASCONF chunks toward us,
1804 * we now need the ability to cache multiple ACKs. The section
1805 * describes in detail how they are cached and cleaned up.
1807 struct list_head asconf_ack_list
;
1809 /* These ASCONF chunks are waiting to be sent.
1811 * These chunaks can't be pushed to outqueue until receiving
1812 * ASCONF_ACK for the previous ASCONF indicated by
1813 * addip_last_asconf, so as to guarantee that only one ASCONF
1814 * is in flight at any time.
1816 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1818 * In defining the ASCONF Chunk transfer procedures, it is
1819 * essential that these transfers MUST NOT cause congestion
1820 * within the network. To achieve this, we place these
1821 * restrictions on the transfer 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).
1833 * [I really think this is EXACTLY the sort of intelligence
1834 * which already resides in sctp_outq. Please move this
1835 * queue and its supporting logic down there. --piggy]
1837 struct list_head addip_chunk_list
;
1839 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1841 * A2) A serial number should be assigned to the Chunk. The
1842 * serial number SHOULD be a monotonically increasing
1843 * number. The serial number SHOULD be initialized at
1844 * the start of the association to the same value as the
1845 * Initial TSN and every time a new ASCONF chunk is created
1846 * it is incremented by one after assigning the serial number
1847 * to the newly created chunk.
1850 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
1852 * Serial Number : 32 bits (unsigned integer)
1854 * This value represents a Serial Number for the ASCONF
1855 * Chunk. The valid range of Serial Number is from 0 to
1856 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
1857 * after reaching 4294967295.
1860 int src_out_of_asoc_ok
;
1861 union sctp_addr
*asconf_addr_del_pending
;
1862 struct sctp_transport
*new_transport
;
1864 /* SCTP AUTH: list of the endpoint shared keys. These
1865 * keys are provided out of band by the user applicaton
1866 * and can't change during the lifetime of the association
1868 struct list_head endpoint_shared_keys
;
1871 * The current generated assocaition shared key (secret)
1873 struct sctp_auth_bytes
*asoc_shared_key
;
1875 /* SCTP AUTH: hmac id of the first peer requested algorithm
1878 __u16 default_hmac_id
;
1880 __u16 active_key_id
;
1882 __u8 need_ecne
:1, /* Need to send an ECNE Chunk? */
1883 temp
:1, /* Is it a temporary association? */
1888 __u8 strreset_enable
;
1889 __u8 strreset_outstanding
; /* request param count on the fly */
1891 __u32 strreset_outseq
; /* Update after receiving response */
1892 __u32 strreset_inseq
; /* Update after receiving request */
1893 __u32 strreset_result
[2]; /* save the results of last 2 responses */
1895 struct sctp_chunk
*strreset_chunk
; /* save request chunk */
1897 struct sctp_priv_assoc_stats stats
;
1899 int sent_cnt_removable
;
1901 __u64 abandoned_unsent
[SCTP_PR_INDEX(MAX
) + 1];
1902 __u64 abandoned_sent
[SCTP_PR_INDEX(MAX
) + 1];
1906 /* An eyecatcher for determining if we are really looking at an
1907 * association data structure.
1910 SCTP_ASSOC_EYECATCHER
= 0xa550c123,
1913 /* Recover the outter association structure. */
1914 static inline struct sctp_association
*sctp_assoc(struct sctp_ep_common
*base
)
1916 struct sctp_association
*asoc
;
1918 asoc
= container_of(base
, struct sctp_association
, base
);
1922 /* These are function signatures for manipulating associations. */
1925 struct sctp_association
*
1926 sctp_association_new(const struct sctp_endpoint
*, const struct sock
*,
1927 sctp_scope_t scope
, gfp_t gfp
);
1928 void sctp_association_free(struct sctp_association
*);
1929 void sctp_association_put(struct sctp_association
*);
1930 void sctp_association_hold(struct sctp_association
*);
1932 struct sctp_transport
*sctp_assoc_choose_alter_transport(
1933 struct sctp_association
*, struct sctp_transport
*);
1934 void sctp_assoc_update_retran_path(struct sctp_association
*);
1935 struct sctp_transport
*sctp_assoc_lookup_paddr(const struct sctp_association
*,
1936 const union sctp_addr
*);
1937 int sctp_assoc_lookup_laddr(struct sctp_association
*asoc
,
1938 const union sctp_addr
*laddr
);
1939 struct sctp_transport
*sctp_assoc_add_peer(struct sctp_association
*,
1940 const union sctp_addr
*address
,
1942 const int peer_state
);
1943 void sctp_assoc_del_peer(struct sctp_association
*asoc
,
1944 const union sctp_addr
*addr
);
1945 void sctp_assoc_rm_peer(struct sctp_association
*asoc
,
1946 struct sctp_transport
*peer
);
1947 void sctp_assoc_control_transport(struct sctp_association
*,
1948 struct sctp_transport
*,
1949 sctp_transport_cmd_t
, sctp_sn_error_t
);
1950 struct sctp_transport
*sctp_assoc_lookup_tsn(struct sctp_association
*, __u32
);
1951 struct sctp_transport
*sctp_assoc_is_match(struct sctp_association
*,
1953 const union sctp_addr
*,
1954 const union sctp_addr
*);
1955 void sctp_assoc_migrate(struct sctp_association
*, struct sock
*);
1956 int sctp_assoc_update(struct sctp_association
*old
,
1957 struct sctp_association
*new);
1959 __u32
sctp_association_get_next_tsn(struct sctp_association
*);
1961 void sctp_assoc_sync_pmtu(struct sctp_association
*asoc
);
1962 void sctp_assoc_rwnd_increase(struct sctp_association
*, unsigned int);
1963 void sctp_assoc_rwnd_decrease(struct sctp_association
*, unsigned int);
1964 void sctp_assoc_set_primary(struct sctp_association
*,
1965 struct sctp_transport
*);
1966 void sctp_assoc_del_nonprimary_peers(struct sctp_association
*,
1967 struct sctp_transport
*);
1968 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association
*,
1969 sctp_scope_t
, gfp_t
);
1970 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association
*,
1971 struct sctp_cookie
*,
1973 int sctp_assoc_set_id(struct sctp_association
*, gfp_t
);
1974 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association
*asoc
);
1975 struct sctp_chunk
*sctp_assoc_lookup_asconf_ack(
1976 const struct sctp_association
*asoc
,
1978 void sctp_asconf_queue_teardown(struct sctp_association
*asoc
);
1980 int sctp_cmp_addr_exact(const union sctp_addr
*ss1
,
1981 const union sctp_addr
*ss2
);
1982 struct sctp_chunk
*sctp_get_ecne_prepend(struct sctp_association
*asoc
);
1984 /* A convenience structure to parse out SCTP specific CMSGs. */
1985 typedef struct sctp_cmsgs
{
1986 struct sctp_initmsg
*init
;
1987 struct sctp_sndrcvinfo
*srinfo
;
1988 struct sctp_sndinfo
*sinfo
;
1991 /* Structure for tracking memory objects */
1995 } sctp_dbg_objcnt_entry_t
;
1997 #endif /* __sctp_structs_h__ */