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 struct sctp_stream
*sctp_stream_new(__u16 incnt
, __u16 outcnt
, gfp_t gfp
);
381 void sctp_stream_free(struct sctp_stream
*stream
);
382 void sctp_stream_clear(struct sctp_stream
*stream
);
384 /* What is the current SSN number for this stream? */
385 #define sctp_ssn_peek(stream, type, sid) \
386 ((stream)->type[sid].ssn)
388 /* Return the next SSN number for this stream. */
389 #define sctp_ssn_next(stream, type, sid) \
390 ((stream)->type[sid].ssn++)
392 /* Skip over this ssn and all below. */
393 #define sctp_ssn_skip(stream, type, sid, ssn) \
394 ((stream)->type[sid].ssn = ssn + 1)
397 * Pointers to address related SCTP functions.
398 * (i.e. things that depend on the address family.)
401 int (*sctp_xmit
) (struct sk_buff
*skb
,
402 struct sctp_transport
*);
403 int (*setsockopt
) (struct sock
*sk
,
407 unsigned int optlen
);
408 int (*getsockopt
) (struct sock
*sk
,
413 int (*compat_setsockopt
) (struct sock
*sk
,
417 unsigned int optlen
);
418 int (*compat_getsockopt
) (struct sock
*sk
,
423 void (*get_dst
) (struct sctp_transport
*t
,
424 union sctp_addr
*saddr
,
427 void (*get_saddr
) (struct sctp_sock
*sk
,
428 struct sctp_transport
*t
,
430 void (*copy_addrlist
) (struct list_head
*,
431 struct net_device
*);
432 int (*cmp_addr
) (const union sctp_addr
*addr1
,
433 const union sctp_addr
*addr2
);
434 void (*addr_copy
) (union sctp_addr
*dst
,
435 union sctp_addr
*src
);
436 void (*from_skb
) (union sctp_addr
*,
439 void (*from_sk
) (union sctp_addr
*,
441 void (*from_addr_param
) (union sctp_addr
*,
442 union sctp_addr_param
*,
443 __be16 port
, int iif
);
444 int (*to_addr_param
) (const union sctp_addr
*,
445 union sctp_addr_param
*);
446 int (*addr_valid
) (union sctp_addr
*,
448 const struct sk_buff
*);
449 sctp_scope_t (*scope
) (union sctp_addr
*);
450 void (*inaddr_any
) (union sctp_addr
*, __be16
);
451 int (*is_any
) (const union sctp_addr
*);
452 int (*available
) (union sctp_addr
*,
454 int (*skb_iif
) (const struct sk_buff
*sk
);
455 int (*is_ce
) (const struct sk_buff
*sk
);
456 void (*seq_dump_addr
)(struct seq_file
*seq
,
457 union sctp_addr
*addr
);
458 void (*ecn_capable
)(struct sock
*sk
);
459 __u16 net_header_len
;
461 sa_family_t sa_family
;
462 struct list_head list
;
465 struct sctp_af
*sctp_get_af_specific(sa_family_t
);
466 int sctp_register_af(struct sctp_af
*);
468 /* Protocol family functions. */
470 void (*event_msgname
)(struct sctp_ulpevent
*, char *, int *);
471 void (*skb_msgname
) (struct sk_buff
*, char *, int *);
472 int (*af_supported
) (sa_family_t
, struct sctp_sock
*);
473 int (*cmp_addr
) (const union sctp_addr
*,
474 const union sctp_addr
*,
476 int (*bind_verify
) (struct sctp_sock
*, union sctp_addr
*);
477 int (*send_verify
) (struct sctp_sock
*, union sctp_addr
*);
478 int (*supported_addrs
)(const struct sctp_sock
*, __be16
*);
479 struct sock
*(*create_accept_sk
) (struct sock
*sk
,
480 struct sctp_association
*asoc
,
482 int (*addr_to_user
)(struct sctp_sock
*sk
, union sctp_addr
*addr
);
483 void (*to_sk_saddr
)(union sctp_addr
*, struct sock
*sk
);
484 void (*to_sk_daddr
)(union sctp_addr
*, struct sock
*sk
);
489 /* Structure to track chunk fragments that have been acked, but peer
490 * fragments of the same message have not.
492 struct sctp_datamsg
{
493 /* Chunks waiting to be submitted to lower layer. */
494 struct list_head chunks
;
495 /* Reference counting. */
497 /* When is this message no longer interesting to the peer? */
498 unsigned long expires_at
;
499 /* Did the messenge fail to send? */
502 can_delay
; /* should this message be Nagle delayed */
505 struct sctp_datamsg
*sctp_datamsg_from_user(struct sctp_association
*,
506 struct sctp_sndrcvinfo
*,
508 void sctp_datamsg_free(struct sctp_datamsg
*);
509 void sctp_datamsg_put(struct sctp_datamsg
*);
510 void sctp_chunk_fail(struct sctp_chunk
*, int error
);
511 int sctp_chunk_abandoned(struct sctp_chunk
*);
513 /* RFC2960 1.4 Key Terms
515 * o Chunk: A unit of information within an SCTP packet, consisting of
516 * a chunk header and chunk-specific content.
518 * As a matter of convenience, we remember the SCTP common header for
519 * each chunk as well as a few other header pointers...
522 struct list_head list
;
526 /* How many times this chunk have been sent, for prsctp RTX policy */
529 /* This is our link to the per-transport transmitted list. */
530 struct list_head transmitted_list
;
532 /* This field is used by chunks that hold fragmented data.
533 * For the first fragment this is the list that holds the rest of
534 * fragments. For the remaining fragments, this is the link to the
535 * frag_list maintained in the first fragment.
537 struct list_head frag_list
;
539 /* This points to the sk_buff containing the actual data. */
542 /* In case of GSO packets, this will store the head one */
543 struct sk_buff
*head_skb
;
545 /* These are the SCTP headers by reverse order in a packet.
546 * Note that some of these may happen more than once. In that
547 * case, we point at the "current" one, whatever that means
548 * for that level of header.
551 /* We point this at the FIRST TLV parameter to chunk_hdr. */
552 union sctp_params param_hdr
;
555 struct sctp_datahdr
*data_hdr
;
556 struct sctp_inithdr
*init_hdr
;
557 struct sctp_sackhdr
*sack_hdr
;
558 struct sctp_heartbeathdr
*hb_hdr
;
559 struct sctp_sender_hb_info
*hbs_hdr
;
560 struct sctp_shutdownhdr
*shutdown_hdr
;
561 struct sctp_signed_cookie
*cookie_hdr
;
562 struct sctp_ecnehdr
*ecne_hdr
;
563 struct sctp_cwrhdr
*ecn_cwr_hdr
;
564 struct sctp_errhdr
*err_hdr
;
565 struct sctp_addiphdr
*addip_hdr
;
566 struct sctp_fwdtsn_hdr
*fwdtsn_hdr
;
567 struct sctp_authhdr
*auth_hdr
;
572 struct sctp_chunkhdr
*chunk_hdr
;
573 struct sctphdr
*sctp_hdr
;
575 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
576 struct sctp_sndrcvinfo sinfo
;
578 /* Which association does this belong to? */
579 struct sctp_association
*asoc
;
581 /* What endpoint received this chunk? */
582 struct sctp_ep_common
*rcvr
;
584 /* We fill this in if we are calculating RTT. */
585 unsigned long sent_at
;
587 /* What is the origin IP address for this chunk? */
588 union sctp_addr source
;
589 /* Destination address for this chunk. */
590 union sctp_addr dest
;
592 /* For outbound message, track all fragments for SEND_FAILED. */
593 struct sctp_datamsg
*msg
;
595 /* For an inbound chunk, this tells us where it came from.
596 * For an outbound chunk, it tells us where we'd like it to
597 * go. It is NULL if we have no preference.
599 struct sctp_transport
*transport
;
601 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO
602 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
603 * spec violates the principle premis that all chunks are processed
606 struct sk_buff
*auth_chunk
;
608 #define SCTP_CAN_FRTX 0x0
609 #define SCTP_NEED_FRTX 0x1
610 #define SCTP_DONT_FRTX 0x2
611 __u16 rtt_in_progress
:1, /* This chunk used for RTT calc? */
612 has_tsn
:1, /* Does this chunk have a TSN yet? */
613 has_ssn
:1, /* Does this chunk have a SSN yet? */
614 singleton
:1, /* Only chunk in the packet? */
615 end_of_packet
:1, /* Last chunk in the packet? */
616 ecn_ce_done
:1, /* Have we processed the ECN CE bit? */
617 pdiscard
:1, /* Discard the whole packet now? */
618 tsn_gap_acked
:1, /* Is this chunk acked by a GAP ACK? */
619 data_accepted
:1, /* At least 1 chunk accepted */
620 auth
:1, /* IN: was auth'ed | OUT: needs auth */
621 has_asconf
:1, /* IN: have seen an asconf before */
622 tsn_missing_report
:2, /* Data chunk missing counter. */
623 fast_retransmit
:2; /* Is this chunk fast retransmitted? */
626 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1)
627 void sctp_chunk_hold(struct sctp_chunk
*);
628 void sctp_chunk_put(struct sctp_chunk
*);
629 int sctp_user_addto_chunk(struct sctp_chunk
*chunk
, int len
,
630 struct iov_iter
*from
);
631 void sctp_chunk_free(struct sctp_chunk
*);
632 void *sctp_addto_chunk(struct sctp_chunk
*, int len
, const void *data
);
633 struct sctp_chunk
*sctp_chunkify(struct sk_buff
*,
634 const struct sctp_association
*,
635 struct sock
*, gfp_t gfp
);
636 void sctp_init_addrs(struct sctp_chunk
*, union sctp_addr
*,
638 const union sctp_addr
*sctp_source(const struct sctp_chunk
*chunk
);
641 SCTP_ADDR_NEW
, /* new address added to assoc/ep */
642 SCTP_ADDR_SRC
, /* address can be used as source */
643 SCTP_ADDR_DEL
, /* address about to be deleted */
646 /* This is a structure for holding either an IPv6 or an IPv4 address. */
647 struct sctp_sockaddr_entry
{
648 struct list_head list
;
655 #define SCTP_ADDRESS_TICK_DELAY 500
657 typedef struct sctp_chunk
*(sctp_packet_phandler_t
)(struct sctp_association
*);
659 /* This structure holds lists of chunks as we are assembling for
663 /* These are the SCTP header values (host order) for the packet. */
665 __u16 destination_port
;
668 /* This contains the payload chunks. */
669 struct list_head chunk_list
;
671 /* This is the overhead of the sctp and ip headers. */
673 /* This is the total size of all chunks INCLUDING padding. */
675 /* This is the maximum size this packet may have */
678 /* The packet is destined for this transport address.
679 * The function we finally use to pass down to the next lower
680 * layer lives in the transport structure.
682 struct sctp_transport
*transport
;
684 /* pointer to the auth chunk for this packet */
685 struct sctp_chunk
*auth
;
687 u8 has_cookie_echo
:1, /* This packet contains a COOKIE-ECHO chunk. */
688 has_sack
:1, /* This packet contains a SACK chunk. */
689 has_auth
:1, /* This packet contains an AUTH chunk */
690 has_data
:1, /* This packet contains at least 1 DATA chunk */
691 ipfragok
:1; /* So let ip fragment this packet */
694 void sctp_packet_init(struct sctp_packet
*, struct sctp_transport
*,
695 __u16 sport
, __u16 dport
);
696 void sctp_packet_config(struct sctp_packet
*, __u32 vtag
, int);
697 sctp_xmit_t
sctp_packet_transmit_chunk(struct sctp_packet
*,
698 struct sctp_chunk
*, int, gfp_t
);
699 sctp_xmit_t
sctp_packet_append_chunk(struct sctp_packet
*,
700 struct sctp_chunk
*);
701 int sctp_packet_transmit(struct sctp_packet
*, gfp_t
);
702 void sctp_packet_free(struct sctp_packet
*);
704 static inline int sctp_packet_empty(struct sctp_packet
*packet
)
706 return packet
->size
== packet
->overhead
;
709 /* This represents a remote transport address.
710 * For local transport addresses, we just use union sctp_addr.
712 * RFC2960 Section 1.4 Key Terms
714 * o Transport address: A Transport Address is traditionally defined
715 * by Network Layer address, Transport Layer protocol and Transport
716 * Layer port number. In the case of SCTP running over IP, a
717 * transport address is defined by the combination of an IP address
718 * and an SCTP port number (where SCTP is the Transport protocol).
720 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
722 * o The sender keeps a separate congestion control parameter set for
723 * each of the destination addresses it can send to (not each
724 * source-destination pair but for each destination). The parameters
725 * should decay if the address is not used for a long enough time
729 struct sctp_transport
{
730 /* A list of transports. */
731 struct list_head transports
;
732 struct rhlist_head node
;
734 /* Reference counting. */
736 /* RTO-Pending : A flag used to track if one of the DATA
737 * chunks sent to this address is currently being
738 * used to compute a RTT. If this flag is 0,
739 * the next DATA chunk sent to this destination
740 * should be used to compute a RTT and this flag
741 * should be set. Every time the RTT
742 * calculation completes (i.e. the DATA chunk
743 * is SACK'd) clear this flag.
748 * hb_sent : a flag that signals that we have a pending
753 /* Is the Path MTU update pending on this tranport */
756 dst_pending_confirm
:1, /* need to confirm neighbour */
758 /* Has this transport moved the ctsn since we last sacked */
764 /* This is the peer's IP address and port. */
765 union sctp_addr ipaddr
;
767 /* These are the functions we call to handle LLP stuff. */
768 struct sctp_af
*af_specific
;
770 /* Which association do we belong to? */
771 struct sctp_association
*asoc
;
775 * 12.3 Per Transport Address Data
777 * For each destination transport address in the peer's
778 * address list derived from the INIT or INIT ACK chunk, a
779 * number of data elements needs to be maintained including:
781 /* RTO : The current retransmission timeout value. */
784 __u32 rtt
; /* This is the most recent RTT. */
786 /* RTTVAR : The current RTT variation. */
789 /* SRTT : The current smoothed round trip time. */
793 * These are the congestion stats.
795 /* cwnd : The current congestion window. */
796 __u32 cwnd
; /* This is the actual cwnd. */
798 /* ssthresh : The current slow start threshold value. */
801 /* partial : The tracking method for increase of cwnd when in
802 * bytes acked : congestion avoidance mode (see Section 6.2.2)
804 __u32 partial_bytes_acked
;
806 /* Data that has been sent, but not acknowledged. */
809 __u32 burst_limited
; /* Holds old cwnd when max.burst is applied */
812 struct dst_entry
*dst
;
813 /* Source address. */
814 union sctp_addr saddr
;
816 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
817 * the destination address every heartbeat interval.
819 unsigned long hbinterval
;
821 /* SACK delay timeout */
822 unsigned long sackdelay
;
825 /* When was the last time that we heard from this transport? We use
826 * this to pick new active and retran paths.
828 ktime_t last_time_heard
;
830 /* When was the last time that we sent a chunk using this
831 * transport? We use this to check for idle transports
833 unsigned long last_time_sent
;
835 /* Last time(in jiffies) when cwnd is reduced due to the congestion
836 * indication based on ECNE chunk.
838 unsigned long last_time_ecne_reduced
;
840 /* This is the max_retrans value for the transport and will
841 * be initialized from the assocs value. This can be changed
842 * using the SCTP_SET_PEER_ADDR_PARAMS socket option.
846 /* This is the partially failed retrans value for the transport
847 * and will be initialized from the assocs value. This can be changed
848 * using the SCTP_PEER_ADDR_THLDS socket option
851 /* PMTU : The current known path MTU. */
854 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
857 /* The number of times INIT has been sent on this transport. */
860 /* state : The current state of this destination,
861 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
865 /* These are the error stats for this destination. */
867 /* Error count : The current error count for this destination. */
868 unsigned short error_count
;
870 /* Per : A timer used by each destination.
874 * [Everywhere else in the text this is called T3-rtx. -ed]
876 struct timer_list T3_rtx_timer
;
878 /* Heartbeat timer is per destination. */
879 struct timer_list hb_timer
;
881 /* Timer to handle ICMP proto unreachable envets */
882 struct timer_list proto_unreach_timer
;
884 /* Timer to handler reconf chunk rtx */
885 struct timer_list reconf_timer
;
887 /* Since we're using per-destination retransmission timers
888 * (see above), we're also using per-destination "transmitted"
889 * queues. This probably ought to be a private struct
890 * accessible only within the outqueue, but it's not, yet.
892 struct list_head transmitted
;
894 /* We build bundle-able packets for this transport here. */
895 struct sctp_packet packet
;
897 /* This is the list of transports that have chunks to send. */
898 struct list_head send_ready
;
900 /* State information saved for SFR_CACC algorithm. The key
901 * idea in SFR_CACC is to maintain state at the sender on a
902 * per-destination basis when a changeover happens.
903 * char changeover_active;
904 * char cycling_changeover;
905 * __u32 next_tsn_at_change;
906 * char cacc_saw_newack;
909 /* An unsigned integer, which stores the next TSN to be
910 * used by the sender, at the moment of changeover.
912 __u32 next_tsn_at_change
;
914 /* A flag which indicates the occurrence of a changeover */
915 char changeover_active
;
917 /* A flag which indicates whether the change of primary is
918 * the first switch to this destination address during an
921 char cycling_changeover
;
923 /* A temporary flag, which is used during the processing of
924 * a SACK to estimate the causative TSN(s)'s group.
926 char cacc_saw_newack
;
929 /* 64-bit random number sent with heartbeat. */
935 struct sctp_transport
*sctp_transport_new(struct net
*, const union sctp_addr
*,
937 void sctp_transport_set_owner(struct sctp_transport
*,
938 struct sctp_association
*);
939 void sctp_transport_route(struct sctp_transport
*, union sctp_addr
*,
941 void sctp_transport_pmtu(struct sctp_transport
*, struct sock
*sk
);
942 void sctp_transport_free(struct sctp_transport
*);
943 void sctp_transport_reset_t3_rtx(struct sctp_transport
*);
944 void sctp_transport_reset_hb_timer(struct sctp_transport
*);
945 void sctp_transport_reset_reconf_timer(struct sctp_transport
*transport
);
946 int sctp_transport_hold(struct sctp_transport
*);
947 void sctp_transport_put(struct sctp_transport
*);
948 void sctp_transport_update_rto(struct sctp_transport
*, __u32
);
949 void sctp_transport_raise_cwnd(struct sctp_transport
*, __u32
, __u32
);
950 void sctp_transport_lower_cwnd(struct sctp_transport
*, sctp_lower_cwnd_t
);
951 void sctp_transport_burst_limited(struct sctp_transport
*);
952 void sctp_transport_burst_reset(struct sctp_transport
*);
953 unsigned long sctp_transport_timeout(struct sctp_transport
*);
954 void sctp_transport_reset(struct sctp_transport
*);
955 void sctp_transport_update_pmtu(struct sock
*, struct sctp_transport
*, u32
);
956 void sctp_transport_immediate_rtx(struct sctp_transport
*);
957 void sctp_transport_dst_release(struct sctp_transport
*t
);
958 void sctp_transport_dst_confirm(struct sctp_transport
*t
);
961 /* This is the structure we use to queue packets as they come into
962 * SCTP. We write packets to it and read chunks from it.
965 /* This is actually a queue of sctp_chunk each
966 * containing a partially decoded packet.
968 struct list_head in_chunk_list
;
969 /* This is the packet which is currently off the in queue and is
970 * being worked on through the inbound chunk processing.
972 struct sctp_chunk
*in_progress
;
974 /* This is the delayed task to finish delivering inbound
977 struct work_struct immediate
;
980 void sctp_inq_init(struct sctp_inq
*);
981 void sctp_inq_free(struct sctp_inq
*);
982 void sctp_inq_push(struct sctp_inq
*, struct sctp_chunk
*packet
);
983 struct sctp_chunk
*sctp_inq_pop(struct sctp_inq
*);
984 struct sctp_chunkhdr
*sctp_inq_peek(struct sctp_inq
*);
985 void sctp_inq_set_th_handler(struct sctp_inq
*, work_func_t
);
987 /* This is the structure we use to hold outbound chunks. You push
988 * chunks in and they automatically pop out the other end as bundled
989 * packets (it calls (*output_handler)()).
991 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
992 * and 8.2 of the v13 draft.
994 * It handles retransmissions. The connection to the timeout portion
995 * of the state machine is through sctp_..._timeout() and timeout_handler.
997 * If you feed it SACKs, it will eat them.
999 * If you give it big chunks, it will fragment them.
1001 * It assigns TSN's to data chunks. This happens at the last possible
1002 * instant before transmission.
1004 * When free()'d, it empties itself out via output_handler().
1007 struct sctp_association
*asoc
;
1009 /* Data pending that has never been transmitted. */
1010 struct list_head out_chunk_list
;
1012 unsigned int out_qlen
; /* Total length of queued data chunks. */
1014 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1017 /* These are control chunks we want to send. */
1018 struct list_head control_chunk_list
;
1020 /* These are chunks that have been sacked but are above the
1021 * CTSN, or cumulative tsn ack point.
1023 struct list_head sacked
;
1025 /* Put chunks on this list to schedule them for
1028 struct list_head retransmit
;
1030 /* Put chunks on this list to save them for FWD TSN processing as
1031 * they were abandoned.
1033 struct list_head abandoned
;
1035 /* How many unackd bytes do we have in-flight? */
1036 __u32 outstanding_bytes
;
1038 /* Are we doing fast-rtx on this queue */
1045 void sctp_outq_init(struct sctp_association
*, struct sctp_outq
*);
1046 void sctp_outq_teardown(struct sctp_outq
*);
1047 void sctp_outq_free(struct sctp_outq
*);
1048 void sctp_outq_tail(struct sctp_outq
*, struct sctp_chunk
*chunk
, gfp_t
);
1049 int sctp_outq_sack(struct sctp_outq
*, struct sctp_chunk
*);
1050 int sctp_outq_is_empty(const struct sctp_outq
*);
1051 void sctp_outq_restart(struct sctp_outq
*);
1053 void sctp_retransmit(struct sctp_outq
*, struct sctp_transport
*,
1054 sctp_retransmit_reason_t
);
1055 void sctp_retransmit_mark(struct sctp_outq
*, struct sctp_transport
*, __u8
);
1056 void sctp_outq_uncork(struct sctp_outq
*, gfp_t gfp
);
1057 void sctp_prsctp_prune(struct sctp_association
*asoc
,
1058 struct sctp_sndrcvinfo
*sinfo
, int msg_len
);
1059 /* Uncork and flush an outqueue. */
1060 static inline void sctp_outq_cork(struct sctp_outq
*q
)
1065 /* SCTP skb control block.
1066 * sctp_input_cb is currently used on rx and sock rx queue
1068 struct sctp_input_cb
{
1070 struct inet_skb_parm h4
;
1071 #if IS_ENABLED(CONFIG_IPV6)
1072 struct inet6_skb_parm h6
;
1075 struct sctp_chunk
*chunk
;
1078 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0]))
1080 static inline const struct sk_buff
*sctp_gso_headskb(const struct sk_buff
*skb
)
1082 const struct sctp_chunk
*chunk
= SCTP_INPUT_CB(skb
)->chunk
;
1084 return chunk
->head_skb
? : skb
;
1087 /* These bind address data fields common between endpoints and associations */
1088 struct sctp_bind_addr
{
1090 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1092 * SCTP Port: The local SCTP port number the endpoint is
1097 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1099 * Address List: The list of IP addresses that this instance
1100 * has bound. This information is passed to one's
1101 * peer(s) in INIT and INIT ACK chunks.
1103 struct list_head address_list
;
1106 void sctp_bind_addr_init(struct sctp_bind_addr
*, __u16 port
);
1107 void sctp_bind_addr_free(struct sctp_bind_addr
*);
1108 int sctp_bind_addr_copy(struct net
*net
, struct sctp_bind_addr
*dest
,
1109 const struct sctp_bind_addr
*src
,
1110 sctp_scope_t scope
, gfp_t gfp
,
1112 int sctp_bind_addr_dup(struct sctp_bind_addr
*dest
,
1113 const struct sctp_bind_addr
*src
,
1115 int sctp_add_bind_addr(struct sctp_bind_addr
*, union sctp_addr
*,
1116 int new_size
, __u8 addr_state
, gfp_t gfp
);
1117 int sctp_del_bind_addr(struct sctp_bind_addr
*, union sctp_addr
*);
1118 int sctp_bind_addr_match(struct sctp_bind_addr
*, const union sctp_addr
*,
1119 struct sctp_sock
*);
1120 int sctp_bind_addr_conflict(struct sctp_bind_addr
*, const union sctp_addr
*,
1121 struct sctp_sock
*, struct sctp_sock
*);
1122 int sctp_bind_addr_state(const struct sctp_bind_addr
*bp
,
1123 const union sctp_addr
*addr
);
1124 union sctp_addr
*sctp_find_unmatch_addr(struct sctp_bind_addr
*bp
,
1125 const union sctp_addr
*addrs
,
1127 struct sctp_sock
*opt
);
1128 union sctp_params
sctp_bind_addrs_to_raw(const struct sctp_bind_addr
*bp
,
1131 int sctp_raw_to_bind_addrs(struct sctp_bind_addr
*bp
, __u8
*raw
, int len
,
1132 __u16 port
, gfp_t gfp
);
1134 sctp_scope_t
sctp_scope(const union sctp_addr
*);
1135 int sctp_in_scope(struct net
*net
, const union sctp_addr
*addr
, const sctp_scope_t scope
);
1136 int sctp_is_any(struct sock
*sk
, const union sctp_addr
*addr
);
1137 int sctp_is_ep_boundall(struct sock
*sk
);
1140 /* What type of endpoint? */
1142 SCTP_EP_TYPE_SOCKET
,
1143 SCTP_EP_TYPE_ASSOCIATION
,
1144 } sctp_endpoint_type_t
;
1147 * A common base class to bridge the implmentation view of a
1148 * socket (usually listening) endpoint versus an association's
1150 * This common structure is useful for several purposes:
1151 * 1) Common interface for lookup routines.
1152 * a) Subfunctions work for either endpoint or association
1153 * b) Single interface to lookup allows hiding the lookup lock rather
1154 * than acquiring it externally.
1155 * 2) Common interface for the inbound chunk handling/state machine.
1156 * 3) Common object handling routines for reference counting, etc.
1157 * 4) Disentangle association lookup from endpoint lookup, where we
1158 * do not have to find our endpoint to find our association.
1162 struct sctp_ep_common
{
1163 /* Fields to help us manage our entries in the hash tables. */
1164 struct hlist_node node
;
1167 /* Runtime type information. What kind of endpoint is this? */
1168 sctp_endpoint_type_t type
;
1170 /* Some fields to help us manage this object.
1171 * refcnt - Reference count access to this object.
1172 * dead - Do not attempt to use this object.
1177 /* What socket does this endpoint belong to? */
1180 /* This is where we receive inbound chunks. */
1181 struct sctp_inq inqueue
;
1183 /* This substructure includes the defining parameters of the
1185 * bind_addr.port is our shared port number.
1186 * bind_addr.address_list is our set of local IP addresses.
1188 struct sctp_bind_addr bind_addr
;
1192 /* RFC Section 1.4 Key Terms
1194 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1195 * multi-homed host, an SCTP endpoint is represented to its peers as a
1196 * combination of a set of eligible destination transport addresses to
1197 * which SCTP packets can be sent and a set of eligible source
1198 * transport addresses from which SCTP packets can be received.
1199 * All transport addresses used by an SCTP endpoint must use the
1200 * same port number, but can use multiple IP addresses. A transport
1201 * address used by an SCTP endpoint must not be used by another
1202 * SCTP endpoint. In other words, a transport address is unique
1203 * to an SCTP endpoint.
1205 * From an implementation perspective, each socket has one of these.
1206 * A TCP-style socket will have exactly one association on one of
1207 * these. An UDP-style socket will have multiple associations hanging
1211 struct sctp_endpoint
{
1212 /* Common substructure for endpoint and association. */
1213 struct sctp_ep_common base
;
1215 /* Associations: A list of current associations and mappings
1216 * to the data consumers for each association. This
1217 * may be in the form of a hash table or other
1218 * implementation dependent structure. The data
1219 * consumers may be process identification
1220 * information such as file descriptors, named pipe
1221 * pointer, or table pointers dependent on how SCTP
1224 /* This is really a list of struct sctp_association entries. */
1225 struct list_head asocs
;
1227 /* Secret Key: A secret key used by this endpoint to compute
1228 * the MAC. This SHOULD be a cryptographic quality
1229 * random number with a sufficient length.
1230 * Discussion in [RFC1750] can be helpful in
1231 * selection of the key.
1233 __u8 secret_key
[SCTP_SECRET_SIZE
];
1235 /* digest: This is a digest of the sctp cookie. This field is
1236 * only used on the receive path when we try to validate
1237 * that the cookie has not been tampered with. We put
1238 * this here so we pre-allocate this once and can re-use
1243 /* sendbuf acct. policy. */
1244 __u32 sndbuf_policy
;
1246 /* rcvbuf acct. policy. */
1247 __u32 rcvbuf_policy
;
1249 /* SCTP AUTH: array of the HMACs that will be allocated
1250 * we need this per association so that we don't serialize
1252 struct crypto_shash
**auth_hmacs
;
1254 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1255 struct sctp_hmac_algo_param
*auth_hmacs_list
;
1257 /* SCTP-AUTH: chunks to authenticate encoded into parameter */
1258 struct sctp_chunks_param
*auth_chunk_list
;
1260 /* SCTP-AUTH: endpoint shared keys */
1261 struct list_head endpoint_shared_keys
;
1262 __u16 active_key_id
;
1267 __u8 strreset_enable
;
1270 /* Recover the outter endpoint structure. */
1271 static inline struct sctp_endpoint
*sctp_ep(struct sctp_ep_common
*base
)
1273 struct sctp_endpoint
*ep
;
1275 ep
= container_of(base
, struct sctp_endpoint
, base
);
1279 /* These are function signatures for manipulating endpoints. */
1280 struct sctp_endpoint
*sctp_endpoint_new(struct sock
*, gfp_t
);
1281 void sctp_endpoint_free(struct sctp_endpoint
*);
1282 void sctp_endpoint_put(struct sctp_endpoint
*);
1283 void sctp_endpoint_hold(struct sctp_endpoint
*);
1284 void sctp_endpoint_add_asoc(struct sctp_endpoint
*, struct sctp_association
*);
1285 struct sctp_association
*sctp_endpoint_lookup_assoc(
1286 const struct sctp_endpoint
*ep
,
1287 const union sctp_addr
*paddr
,
1288 struct sctp_transport
**);
1289 int sctp_endpoint_is_peeled_off(struct sctp_endpoint
*,
1290 const union sctp_addr
*);
1291 struct sctp_endpoint
*sctp_endpoint_is_match(struct sctp_endpoint
*,
1292 struct net
*, const union sctp_addr
*);
1293 int sctp_has_association(struct net
*net
, const union sctp_addr
*laddr
,
1294 const union sctp_addr
*paddr
);
1296 int sctp_verify_init(struct net
*net
, const struct sctp_endpoint
*ep
,
1297 const struct sctp_association
*asoc
,
1298 sctp_cid_t
, sctp_init_chunk_t
*peer_init
,
1299 struct sctp_chunk
*chunk
, struct sctp_chunk
**err_chunk
);
1300 int sctp_process_init(struct sctp_association
*, struct sctp_chunk
*chunk
,
1301 const union sctp_addr
*peer
,
1302 sctp_init_chunk_t
*init
, gfp_t gfp
);
1303 __u32
sctp_generate_tag(const struct sctp_endpoint
*);
1304 __u32
sctp_generate_tsn(const struct sctp_endpoint
*);
1306 struct sctp_inithdr_host
{
1309 __u16 num_outbound_streams
;
1310 __u16 num_inbound_streams
;
1314 struct sctp_stream_out
{
1319 struct sctp_stream_in
{
1323 struct sctp_stream
{
1324 struct sctp_stream_out
*out
;
1325 struct sctp_stream_in
*in
;
1330 #define SCTP_STREAM_CLOSED 0x00
1331 #define SCTP_STREAM_OPEN 0x01
1333 /* SCTP_GET_ASSOC_STATS counters */
1334 struct sctp_priv_assoc_stats
{
1335 /* Maximum observed rto in the association during subsequent
1336 * observations. Value is set to 0 if no RTO measurement took place
1337 * The transport where the max_rto was observed is returned in
1340 struct sockaddr_storage obs_rto_ipaddr
;
1342 /* Total In and Out SACKs received and sent */
1345 /* Total In and Out packets received and sent */
1348 /* Total retransmitted chunks */
1350 /* TSN received > next expected */
1352 /* Duplicate Chunks received */
1354 /* Gap Ack Blocks received */
1356 /* Unordered data chunks sent and received */
1359 /* Ordered data chunks sent and received */
1362 /* Control chunks sent and received */
1369 * 12. Recommended Transmission Control Block (TCB) Parameters
1371 * This section details a recommended set of parameters that should
1372 * be contained within the TCB for an implementation. This section is
1373 * for illustrative purposes and should not be deemed as requirements
1374 * on an implementation or as an exhaustive list of all parameters
1375 * inside an SCTP TCB. Each implementation may need its own additional
1376 * parameters for optimization.
1380 /* Here we have information about each individual association. */
1381 struct sctp_association
{
1383 /* A base structure common to endpoint and association.
1384 * In this context, it represents the associations's view
1385 * of the local endpoint of the association.
1387 struct sctp_ep_common base
;
1389 /* Associations on the same socket. */
1390 struct list_head asocs
;
1392 /* association id. */
1393 sctp_assoc_t assoc_id
;
1395 /* This is our parent endpoint. */
1396 struct sctp_endpoint
*ep
;
1398 /* These are those association elements needed in the cookie. */
1399 struct sctp_cookie c
;
1401 /* This is all information about our peer. */
1403 /* transport_addr_list
1405 * Peer : A list of SCTP transport addresses that the
1406 * Transport : peer is bound to. This information is derived
1407 * Address : from the INIT or INIT ACK and is used to
1408 * List : associate an inbound packet with a given
1409 * : association. Normally this information is
1410 * : hashed or keyed for quick lookup and access
1412 * : The list is also initialized with the list
1413 * : of addresses passed with the sctp_connectx()
1416 * It is a list of SCTP_transport's.
1418 struct list_head transport_addr_list
;
1422 * Peer Rwnd : Current calculated value of the peer's rwnd.
1428 * Peer : A count of the number of peer addresses
1429 * Transport : in the Peer Transport Address List.
1433 __u16 transport_count
;
1436 * The transport layer port number.
1442 * Primary : This is the current primary destination
1443 * Path : transport address of the peer endpoint. It
1444 * : may also specify a source transport address
1445 * : on this endpoint.
1447 * All of these paths live on transport_addr_list.
1449 * At the bakeoffs, we discovered that the intent of
1450 * primaryPath is that it only changes when the ULP
1451 * asks to have it changed. We add the activePath to
1452 * designate the connection we are currently using to
1453 * transmit new data and most control chunks.
1455 struct sctp_transport
*primary_path
;
1457 /* Cache the primary path address here, when we
1458 * need a an address for msg_name.
1460 union sctp_addr primary_addr
;
1463 * The path that we are currently using to
1464 * transmit new data and most control chunks.
1466 struct sctp_transport
*active_path
;
1470 * RFC2960 6.4 Multi-homed SCTP Endpoints
1472 * Furthermore, when its peer is multi-homed, an
1473 * endpoint SHOULD try to retransmit a chunk to an
1474 * active destination transport address that is
1475 * different from the last destination address to
1476 * which the DATA chunk was sent.
1478 struct sctp_transport
*retran_path
;
1480 /* Pointer to last transport I have sent on. */
1481 struct sctp_transport
*last_sent_to
;
1483 /* This is the last transport I have received DATA on. */
1484 struct sctp_transport
*last_data_from
;
1487 * Mapping An array of bits or bytes indicating which out of
1488 * Array order TSN's have been received (relative to the
1489 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1490 * order packets have been received, this array
1491 * will be set to all zero. This structure may be
1492 * in the form of a circular buffer or bit array.
1494 * Last Rcvd : This is the last TSN received in
1495 * TSN : sequence. This value is set initially by
1496 * : taking the peer's Initial TSN, received in
1497 * : the INIT or INIT ACK chunk, and subtracting
1500 * Throughout most of the specification this is called the
1501 * "Cumulative TSN ACK Point". In this case, we
1502 * ignore the advice in 12.2 in favour of the term
1503 * used in the bulk of the text. This value is hidden
1504 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1506 struct sctp_tsnmap tsn_map
;
1508 /* This mask is used to disable sending the ASCONF chunk
1509 * with specified parameter to peer.
1511 __be16 addip_disabled_mask
;
1513 /* These are capabilities which our peer advertised. */
1514 __u8 ecn_capable
:1, /* Can peer do ECN? */
1515 ipv4_address
:1, /* Peer understands IPv4 addresses? */
1516 ipv6_address
:1, /* Peer understands IPv6 addresses? */
1517 hostname_address
:1, /* Peer understands DNS addresses? */
1518 asconf_capable
:1, /* Does peer support ADDIP? */
1519 prsctp_capable
:1, /* Can peer do PR-SCTP? */
1520 reconf_capable
:1, /* Can peer do RE-CONFIG? */
1521 auth_capable
:1; /* Is peer doing SCTP-AUTH? */
1523 /* sack_needed : This flag indicates if the next received
1524 * : packet is to be responded to with a
1525 * : SACK. This is initialized to 0. When a packet
1526 * : is received sack_cnt is incremented. If this value
1527 * : reaches 2 or more, a SACK is sent and the
1528 * : value is reset to 0. Note: This is used only
1529 * : when no DATA chunks are received out of
1530 * : order. When DATA chunks are out of order,
1531 * : SACK's are not delayed (see Section 6).
1533 __u8 sack_needed
:1, /* Do we need to sack the peer? */
1535 zero_window_announced
:1;
1538 __u32 adaptation_ind
; /* Adaptation Code point. */
1540 struct sctp_inithdr_host i
;
1544 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1545 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1546 * Initial TSN Value minus 1
1550 /* SCTP-AUTH: We need to know pears random number, hmac list
1551 * and authenticated chunk list. All that is part of the
1552 * cookie and these are just pointers to those locations
1554 sctp_random_param_t
*peer_random
;
1555 sctp_chunks_param_t
*peer_chunks
;
1556 sctp_hmac_algo_param_t
*peer_hmacs
;
1559 /* State : A state variable indicating what state the
1560 * : association is in, i.e. COOKIE-WAIT,
1561 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1562 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1564 * Note: No "CLOSED" state is illustrated since if a
1565 * association is "CLOSED" its TCB SHOULD be removed.
1567 * In this implementation we DO have a CLOSED
1568 * state which is used during initiation and shutdown.
1570 * State takes values from SCTP_STATE_*.
1574 /* Overall : The overall association error count.
1575 * Error Count : [Clear this any time I get something.]
1577 int overall_error_count
;
1579 /* The cookie life I award for any cookie. */
1580 ktime_t cookie_life
;
1582 /* These are the association's initial, max, and min RTO values.
1583 * These values will be initialized by system defaults, but can
1584 * be modified via the SCTP_RTOINFO socket option.
1586 unsigned long rto_initial
;
1587 unsigned long rto_max
;
1588 unsigned long rto_min
;
1590 /* Maximum number of new data packets that can be sent in a burst. */
1593 /* This is the max_retrans value for the association. This value will
1594 * be initialized initialized from system defaults, but can be
1595 * modified by the SCTP_ASSOCINFO socket option.
1599 /* This is the partially failed retrans value for the transport
1600 * and will be initialized from the assocs value. This can be
1601 * changed using the SCTP_PEER_ADDR_THLDS socket option
1605 /* Maximum number of times the endpoint will retransmit INIT */
1606 __u16 max_init_attempts
;
1608 /* How many times have we resent an INIT? */
1611 /* The largest timeout or RTO value to use in attempting an INIT */
1612 unsigned long max_init_timeo
;
1614 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1615 * the destination address every heartbeat interval. This value
1616 * will be inherited by all new transports.
1618 unsigned long hbinterval
;
1620 /* This is the max_retrans value for new transports in the
1625 /* Flag that path mtu update is pending */
1628 /* Association : The smallest PMTU discovered for all of the
1629 * PMTU : peer's transport addresses.
1633 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1637 /* SACK delay timeout */
1638 unsigned long sackdelay
;
1640 unsigned long timeouts
[SCTP_NUM_TIMEOUT_TYPES
];
1641 struct timer_list timers
[SCTP_NUM_TIMEOUT_TYPES
];
1643 /* Transport to which SHUTDOWN chunk was last sent. */
1644 struct sctp_transport
*shutdown_last_sent_to
;
1646 /* Transport to which INIT chunk was last sent. */
1647 struct sctp_transport
*init_last_sent_to
;
1649 /* How many times have we resent a SHUTDOWN */
1650 int shutdown_retries
;
1652 /* Next TSN : The next TSN number to be assigned to a new
1653 * : DATA chunk. This is sent in the INIT or INIT
1654 * : ACK chunk to the peer and incremented each
1655 * : time a DATA chunk is assigned a TSN
1656 * : (normally just prior to transmit or during
1662 * Last Rcvd : This is the last TSN received in sequence. This value
1663 * TSN : is set initially by taking the peer's Initial TSN,
1664 * : received in the INIT or INIT ACK chunk, and
1665 * : subtracting one from it.
1667 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1670 __u32 ctsn_ack_point
;
1672 /* PR-SCTP Advanced.Peer.Ack.Point */
1673 __u32 adv_peer_ack_point
;
1675 /* Highest TSN that is acknowledged by incoming SACKs. */
1676 __u32 highest_sacked
;
1678 /* TSN marking the fast recovery exit point */
1679 __u32 fast_recovery_exit
;
1681 /* Flag to track the current fast recovery state */
1684 /* The number of unacknowledged data chunks. Reported through
1685 * the SCTP_STATUS sockopt.
1689 /* The total number of data chunks that we've had to retransmit
1690 * as the result of a T3 timer expiration
1692 __u32 rtx_data_chunks
;
1694 /* This is the association's receive buffer space. This value is used
1695 * to set a_rwnd field in an INIT or a SACK chunk.
1699 /* This is the last advertised value of rwnd over a SACK chunk. */
1702 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1703 * to slop over a maximum of the association's frag_point.
1707 /* Keeps treack of rwnd pressure. This happens when we have
1708 * a window, but not recevie buffer (i.e small packets). This one
1709 * is releases slowly (1 PMTU at a time ).
1713 /* This is the sndbuf size in use for the association.
1714 * This corresponds to the sndbuf size for the association,
1715 * as specified in the sk->sndbuf.
1719 /* This is the amount of memory that this association has allocated
1720 * in the receive path at any given time.
1722 atomic_t rmem_alloc
;
1724 /* This is the wait queue head for send requests waiting on
1725 * the association sndbuf space.
1727 wait_queue_head_t wait
;
1729 /* The message size at which SCTP fragmentation will occur. */
1733 /* Counter used to count INIT errors. */
1734 int init_err_counter
;
1736 /* Count the number of INIT cycles (for doubling timeout). */
1739 /* Default send parameters. */
1740 __u16 default_stream
;
1741 __u16 default_flags
;
1743 __u32 default_context
;
1744 __u32 default_timetolive
;
1746 /* Default receive parameters */
1747 __u32 default_rcv_context
;
1750 struct sctp_stream
*stream
;
1752 /* All outbound chunks go through this structure. */
1753 struct sctp_outq outqueue
;
1755 /* A smart pipe that will handle reordering and fragmentation,
1756 * as well as handle passing events up to the ULP.
1758 struct sctp_ulpq ulpq
;
1760 /* Last TSN that caused an ECNE Chunk to be sent. */
1761 __u32 last_ecne_tsn
;
1763 /* Last TSN that caused a CWR Chunk to be sent. */
1766 /* How many duplicated TSNs have we seen? */
1769 /* These are to support
1770 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1771 * and Enforcement of Flow and Message Limits"
1772 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1773 * or "ADDIP" for short.
1778 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1780 * R1) One and only one ASCONF Chunk MAY be in transit and
1781 * unacknowledged at any one time. If a sender, after sending
1782 * an ASCONF chunk, decides it needs to transfer another
1783 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1784 * returns from the previous ASCONF Chunk before sending a
1785 * subsequent ASCONF. Note this restriction binds each side,
1786 * so at any time two ASCONF may be in-transit on any given
1787 * association (one sent from each endpoint).
1789 * [This is our one-and-only-one ASCONF in flight. If we do
1790 * not have an ASCONF in flight, this is NULL.]
1792 struct sctp_chunk
*addip_last_asconf
;
1794 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
1796 * This is needed to implement itmes E1 - E4 of the updated
1797 * spec. Here is the justification:
1799 * Since the peer may bundle multiple ASCONF chunks toward us,
1800 * we now need the ability to cache multiple ACKs. The section
1801 * describes in detail how they are cached and cleaned up.
1803 struct list_head asconf_ack_list
;
1805 /* These ASCONF chunks are waiting to be sent.
1807 * These chunaks can't be pushed to outqueue until receiving
1808 * ASCONF_ACK for the previous ASCONF indicated by
1809 * addip_last_asconf, so as to guarantee that only one ASCONF
1810 * is in flight at any time.
1812 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1814 * In defining the ASCONF Chunk transfer procedures, it is
1815 * essential that these transfers MUST NOT cause congestion
1816 * within the network. To achieve this, we place these
1817 * restrictions on the transfer of ASCONF Chunks:
1819 * R1) One and only one ASCONF Chunk MAY be in transit and
1820 * unacknowledged at any one time. If a sender, after sending
1821 * an ASCONF chunk, decides it needs to transfer another
1822 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1823 * returns from the previous ASCONF Chunk before sending a
1824 * subsequent ASCONF. Note this restriction binds each side,
1825 * so at any time two ASCONF may be in-transit on any given
1826 * association (one sent from each endpoint).
1829 * [I really think this is EXACTLY the sort of intelligence
1830 * which already resides in sctp_outq. Please move this
1831 * queue and its supporting logic down there. --piggy]
1833 struct list_head addip_chunk_list
;
1835 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1837 * A2) A serial number should be assigned to the Chunk. The
1838 * serial number SHOULD be a monotonically increasing
1839 * number. The serial number SHOULD be initialized at
1840 * the start of the association to the same value as the
1841 * Initial TSN and every time a new ASCONF chunk is created
1842 * it is incremented by one after assigning the serial number
1843 * to the newly created chunk.
1846 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
1848 * Serial Number : 32 bits (unsigned integer)
1850 * This value represents a Serial Number for the ASCONF
1851 * Chunk. The valid range of Serial Number is from 0 to
1852 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
1853 * after reaching 4294967295.
1856 int src_out_of_asoc_ok
;
1857 union sctp_addr
*asconf_addr_del_pending
;
1858 struct sctp_transport
*new_transport
;
1860 /* SCTP AUTH: list of the endpoint shared keys. These
1861 * keys are provided out of band by the user applicaton
1862 * and can't change during the lifetime of the association
1864 struct list_head endpoint_shared_keys
;
1867 * The current generated assocaition shared key (secret)
1869 struct sctp_auth_bytes
*asoc_shared_key
;
1871 /* SCTP AUTH: hmac id of the first peer requested algorithm
1874 __u16 default_hmac_id
;
1876 __u16 active_key_id
;
1878 __u8 need_ecne
:1, /* Need to send an ECNE Chunk? */
1879 temp
:1, /* Is it a temporary association? */
1884 __u8 strreset_enable
;
1885 __u8 strreset_outstanding
; /* request param count on the fly */
1887 __u32 strreset_outseq
; /* Update after receiving response */
1888 __u32 strreset_inseq
; /* Update after receiving request */
1890 struct sctp_chunk
*strreset_chunk
; /* save request chunk */
1892 struct sctp_priv_assoc_stats stats
;
1894 int sent_cnt_removable
;
1896 __u64 abandoned_unsent
[SCTP_PR_INDEX(MAX
) + 1];
1897 __u64 abandoned_sent
[SCTP_PR_INDEX(MAX
) + 1];
1901 /* An eyecatcher for determining if we are really looking at an
1902 * association data structure.
1905 SCTP_ASSOC_EYECATCHER
= 0xa550c123,
1908 /* Recover the outter association structure. */
1909 static inline struct sctp_association
*sctp_assoc(struct sctp_ep_common
*base
)
1911 struct sctp_association
*asoc
;
1913 asoc
= container_of(base
, struct sctp_association
, base
);
1917 /* These are function signatures for manipulating associations. */
1920 struct sctp_association
*
1921 sctp_association_new(const struct sctp_endpoint
*, const struct sock
*,
1922 sctp_scope_t scope
, gfp_t gfp
);
1923 void sctp_association_free(struct sctp_association
*);
1924 void sctp_association_put(struct sctp_association
*);
1925 void sctp_association_hold(struct sctp_association
*);
1927 struct sctp_transport
*sctp_assoc_choose_alter_transport(
1928 struct sctp_association
*, struct sctp_transport
*);
1929 void sctp_assoc_update_retran_path(struct sctp_association
*);
1930 struct sctp_transport
*sctp_assoc_lookup_paddr(const struct sctp_association
*,
1931 const union sctp_addr
*);
1932 int sctp_assoc_lookup_laddr(struct sctp_association
*asoc
,
1933 const union sctp_addr
*laddr
);
1934 struct sctp_transport
*sctp_assoc_add_peer(struct sctp_association
*,
1935 const union sctp_addr
*address
,
1937 const int peer_state
);
1938 void sctp_assoc_del_peer(struct sctp_association
*asoc
,
1939 const union sctp_addr
*addr
);
1940 void sctp_assoc_rm_peer(struct sctp_association
*asoc
,
1941 struct sctp_transport
*peer
);
1942 void sctp_assoc_control_transport(struct sctp_association
*,
1943 struct sctp_transport
*,
1944 sctp_transport_cmd_t
, sctp_sn_error_t
);
1945 struct sctp_transport
*sctp_assoc_lookup_tsn(struct sctp_association
*, __u32
);
1946 struct sctp_transport
*sctp_assoc_is_match(struct sctp_association
*,
1948 const union sctp_addr
*,
1949 const union sctp_addr
*);
1950 void sctp_assoc_migrate(struct sctp_association
*, struct sock
*);
1951 void sctp_assoc_update(struct sctp_association
*old
,
1952 struct sctp_association
*new);
1954 __u32
sctp_association_get_next_tsn(struct sctp_association
*);
1956 void sctp_assoc_sync_pmtu(struct sock
*, struct sctp_association
*);
1957 void sctp_assoc_rwnd_increase(struct sctp_association
*, unsigned int);
1958 void sctp_assoc_rwnd_decrease(struct sctp_association
*, unsigned int);
1959 void sctp_assoc_set_primary(struct sctp_association
*,
1960 struct sctp_transport
*);
1961 void sctp_assoc_del_nonprimary_peers(struct sctp_association
*,
1962 struct sctp_transport
*);
1963 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association
*,
1964 sctp_scope_t
, gfp_t
);
1965 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association
*,
1966 struct sctp_cookie
*,
1968 int sctp_assoc_set_id(struct sctp_association
*, gfp_t
);
1969 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association
*asoc
);
1970 struct sctp_chunk
*sctp_assoc_lookup_asconf_ack(
1971 const struct sctp_association
*asoc
,
1973 void sctp_asconf_queue_teardown(struct sctp_association
*asoc
);
1975 int sctp_cmp_addr_exact(const union sctp_addr
*ss1
,
1976 const union sctp_addr
*ss2
);
1977 struct sctp_chunk
*sctp_get_ecne_prepend(struct sctp_association
*asoc
);
1979 /* A convenience structure to parse out SCTP specific CMSGs. */
1980 typedef struct sctp_cmsgs
{
1981 struct sctp_initmsg
*init
;
1982 struct sctp_sndrcvinfo
*srinfo
;
1983 struct sctp_sndinfo
*sinfo
;
1986 /* Structure for tracking memory objects */
1990 } sctp_dbg_objcnt_entry_t
;
1992 #endif /* __sctp_structs_h__ */