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-types.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/flex_array.h> /* We need flex_array. */
61 #include <linux/sctp.h> /* We need sctp* header structs. */
62 #include <net/sctp/auth.h> /* We need auth specific structs */
63 #include <net/ip.h> /* For inet_skb_parm */
65 /* A convenience structure for handling sockaddr structures.
66 * We should wean ourselves off this.
69 struct sockaddr_in v4
;
70 struct sockaddr_in6 v6
;
74 /* Forward declarations for data structures. */
77 struct sctp_association
;
78 struct sctp_transport
;
83 struct sctp_bind_addr
;
85 struct sctp_ep_common
;
90 #include <net/sctp/tsnmap.h>
91 #include <net/sctp/ulpevent.h>
92 #include <net/sctp/ulpqueue.h>
93 #include <net/sctp/stream_interleave.h>
95 /* Structures useful for managing bind/connect. */
97 struct sctp_bind_bucket
{
99 unsigned short fastreuse
;
100 struct hlist_node node
;
101 struct hlist_head owner
;
105 struct sctp_bind_hashbucket
{
107 struct hlist_head chain
;
110 /* Used for hashing all associations. */
111 struct sctp_hashbucket
{
113 struct hlist_head chain
;
114 } __attribute__((__aligned__(8)));
117 /* The SCTP globals structure. */
118 extern struct sctp_globals
{
119 /* This is a list of groups of functions for each address
120 * family that we support.
122 struct list_head address_families
;
124 /* This is the hash of all endpoints. */
125 struct sctp_hashbucket
*ep_hashtable
;
126 /* This is the sctp port control hash. */
127 struct sctp_bind_hashbucket
*port_hashtable
;
128 /* This is the hash of all transports. */
129 struct rhltable transport_hashtable
;
131 /* Sizes of above hashtables. */
135 /* Default initialization values to be applied to new associations. */
137 __u16 max_outstreams
;
139 /* Flag to indicate whether computing and verifying checksum
141 bool checksum_disable
;
144 #define sctp_max_instreams (sctp_globals.max_instreams)
145 #define sctp_max_outstreams (sctp_globals.max_outstreams)
146 #define sctp_address_families (sctp_globals.address_families)
147 #define sctp_ep_hashsize (sctp_globals.ep_hashsize)
148 #define sctp_ep_hashtable (sctp_globals.ep_hashtable)
149 #define sctp_port_hashsize (sctp_globals.port_hashsize)
150 #define sctp_port_hashtable (sctp_globals.port_hashtable)
151 #define sctp_transport_hashtable (sctp_globals.transport_hashtable)
152 #define sctp_checksum_disable (sctp_globals.checksum_disable)
154 /* SCTP Socket type: UDP or TCP style. */
155 enum sctp_socket_type
{
157 SCTP_SOCKET_UDP_HIGH_BANDWIDTH
,
161 /* Per socket SCTP information. */
163 /* inet_sock has to be the first member of sctp_sock */
164 struct inet_sock inet
;
165 /* What kind of a socket is this? */
166 enum sctp_socket_type type
;
168 /* PF_ family specific functions. */
171 /* Access to HMAC transform. */
172 struct crypto_shash
*hmac
;
175 /* What is our base endpointer? */
176 struct sctp_endpoint
*ep
;
178 struct sctp_bind_bucket
*bind_hash
;
179 /* Various Socket Options. */
180 __u16 default_stream
;
183 __u32 default_context
;
184 __u32 default_timetolive
;
185 __u32 default_rcv_context
;
188 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
189 * the destination address every heartbeat interval. This value
190 * will be inherited by all new associations.
194 /* This is the max_retrans value for new associations. */
200 /* The initial Path MTU to use for new associations. */
203 /* The default SACK delay timeout for new associations. */
207 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
210 struct sctp_rtoinfo rtoinfo
;
211 struct sctp_paddrparams paddrparam
;
212 struct sctp_assocparams assocparams
;
215 * These two structures must be grouped together for the usercopy
218 struct sctp_event_subscribe subscribe
;
219 struct sctp_initmsg initmsg
;
224 __u32 adaptation_ind
;
234 data_ready_signalled
:1;
237 /* Receive to here while partial delivery is in effect. */
238 struct sk_buff_head pd_lobby
;
240 /* These must be the last fields, as they will skipped on copies,
241 * like on accept and peeloff operations
243 struct list_head auto_asconf_list
;
247 static inline struct sctp_sock
*sctp_sk(const struct sock
*sk
)
249 return (struct sctp_sock
*)sk
;
252 static inline struct sock
*sctp_opt2sk(const struct sctp_sock
*sp
)
254 return (struct sock
*)sp
;
257 #if IS_ENABLED(CONFIG_IPV6)
259 struct sctp_sock sctp
;
260 struct ipv6_pinfo inet6
;
262 #endif /* CONFIG_IPV6 */
265 /* This is our APPLICATION-SPECIFIC state cookie.
266 * THIS IS NOT DICTATED BY THE SPECIFICATION.
268 /* These are the parts of an association which we send in the cookie.
269 * Most of these are straight out of:
270 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
276 /* My : Tag expected in every inbound packet and sent
277 * Verification: in the INIT or INIT ACK chunk.
282 /* Peer's : Tag expected in every outbound packet except
283 * Verification: in the INIT chunk.
288 /* The rest of these are not from the spec, but really need to
292 /* My Tie Tag : Assist in discovering a restarting association. */
295 /* Peer's Tie Tag: Assist in discovering a restarting association. */
298 /* When does this cookie expire? */
301 /* Number of inbound/outbound streams which are set
302 * and negotiated during the INIT process.
304 __u16 sinit_num_ostreams
;
305 __u16 sinit_max_instreams
;
307 /* This is the first sequence number I used. */
310 /* This holds the originating address of the INIT packet. */
311 union sctp_addr peer_addr
;
314 * Include the source port of the INIT-ACK
320 /* Padding for future use */
323 __u32 adaptation_ind
;
325 __u8 auth_random
[sizeof(struct sctp_paramhdr
) +
326 SCTP_AUTH_RANDOM_LENGTH
];
327 __u8 auth_hmacs
[SCTP_AUTH_NUM_HMACS
* sizeof(__u16
) + 2];
328 __u8 auth_chunks
[sizeof(struct sctp_paramhdr
) + SCTP_AUTH_MAX_CHUNKS
];
330 /* This is a shim for my peer's INIT packet, followed by
331 * a copy of the raw address list of the association.
332 * The length of the raw address list is saved in the
333 * raw_addr_list_len field, which will be used at the time when
334 * the association TCB is re-constructed from the cookie.
336 __u32 raw_addr_list_len
;
337 struct sctp_init_chunk peer_init
[0];
341 /* The format of our cookie that we send to our peer. */
342 struct sctp_signed_cookie
{
343 __u8 signature
[SCTP_SECRET_SIZE
];
344 __u32 __pad
; /* force sctp_cookie alignment to 64 bits */
345 struct sctp_cookie c
;
348 /* This is another convenience type to allocate memory for address
349 * params for the maximum size and pass such structures around
352 union sctp_addr_param
{
353 struct sctp_paramhdr p
;
354 struct sctp_ipv4addr_param v4
;
355 struct sctp_ipv6addr_param v6
;
358 /* A convenience type to allow walking through the various
359 * parameters and avoid casting all over the place.
363 struct sctp_paramhdr
*p
;
364 struct sctp_cookie_preserve_param
*life
;
365 struct sctp_hostname_param
*dns
;
366 struct sctp_cookie_param
*cookie
;
367 struct sctp_supported_addrs_param
*sat
;
368 struct sctp_ipv4addr_param
*v4
;
369 struct sctp_ipv6addr_param
*v6
;
370 union sctp_addr_param
*addr
;
371 struct sctp_adaptation_ind_param
*aind
;
372 struct sctp_supported_ext_param
*ext
;
373 struct sctp_random_param
*random
;
374 struct sctp_chunks_param
*chunks
;
375 struct sctp_hmac_algo_param
*hmac_algo
;
376 struct sctp_addip_param
*addip
;
379 /* RFC 2960. Section 3.3.5 Heartbeat.
380 * Heartbeat Information: variable length
381 * The Sender-specific Heartbeat Info field should normally include
382 * information about the sender's current time when this HEARTBEAT
383 * chunk is sent and the destination transport address to which this
384 * HEARTBEAT is sent (see Section 8.3).
386 struct sctp_sender_hb_info
{
387 struct sctp_paramhdr param_hdr
;
388 union sctp_addr daddr
;
389 unsigned long sent_at
;
393 int sctp_stream_init(struct sctp_stream
*stream
, __u16 outcnt
, __u16 incnt
,
395 int sctp_stream_init_ext(struct sctp_stream
*stream
, __u16 sid
);
396 void sctp_stream_free(struct sctp_stream
*stream
);
397 void sctp_stream_clear(struct sctp_stream
*stream
);
398 void sctp_stream_update(struct sctp_stream
*stream
, struct sctp_stream
*new);
400 /* What is the current SSN number for this stream? */
401 #define sctp_ssn_peek(stream, type, sid) \
402 (sctp_stream_##type((stream), (sid))->ssn)
404 /* Return the next SSN number for this stream. */
405 #define sctp_ssn_next(stream, type, sid) \
406 (sctp_stream_##type((stream), (sid))->ssn++)
408 /* Skip over this ssn and all below. */
409 #define sctp_ssn_skip(stream, type, sid, ssn) \
410 (sctp_stream_##type((stream), (sid))->ssn = ssn + 1)
412 /* What is the current MID number for this stream? */
413 #define sctp_mid_peek(stream, type, sid) \
414 (sctp_stream_##type((stream), (sid))->mid)
416 /* Return the next MID number for this stream. */
417 #define sctp_mid_next(stream, type, sid) \
418 (sctp_stream_##type((stream), (sid))->mid++)
420 /* Skip over this mid and all below. */
421 #define sctp_mid_skip(stream, type, sid, mid) \
422 (sctp_stream_##type((stream), (sid))->mid = mid + 1)
424 /* What is the current MID_uo number for this stream? */
425 #define sctp_mid_uo_peek(stream, type, sid) \
426 (sctp_stream_##type((stream), (sid))->mid_uo)
428 /* Return the next MID_uo number for this stream. */
429 #define sctp_mid_uo_next(stream, type, sid) \
430 (sctp_stream_##type((stream), (sid))->mid_uo++)
433 * Pointers to address related SCTP functions.
434 * (i.e. things that depend on the address family.)
437 int (*sctp_xmit
) (struct sk_buff
*skb
,
438 struct sctp_transport
*);
439 int (*setsockopt
) (struct sock
*sk
,
443 unsigned int optlen
);
444 int (*getsockopt
) (struct sock
*sk
,
449 int (*compat_setsockopt
) (struct sock
*sk
,
453 unsigned int optlen
);
454 int (*compat_getsockopt
) (struct sock
*sk
,
459 void (*get_dst
) (struct sctp_transport
*t
,
460 union sctp_addr
*saddr
,
463 void (*get_saddr
) (struct sctp_sock
*sk
,
464 struct sctp_transport
*t
,
466 void (*copy_addrlist
) (struct list_head
*,
467 struct net_device
*);
468 int (*cmp_addr
) (const union sctp_addr
*addr1
,
469 const union sctp_addr
*addr2
);
470 void (*addr_copy
) (union sctp_addr
*dst
,
471 union sctp_addr
*src
);
472 void (*from_skb
) (union sctp_addr
*,
475 void (*from_sk
) (union sctp_addr
*,
477 void (*from_addr_param
) (union sctp_addr
*,
478 union sctp_addr_param
*,
479 __be16 port
, int iif
);
480 int (*to_addr_param
) (const union sctp_addr
*,
481 union sctp_addr_param
*);
482 int (*addr_valid
) (union sctp_addr
*,
484 const struct sk_buff
*);
485 enum sctp_scope (*scope
)(union sctp_addr
*);
486 void (*inaddr_any
) (union sctp_addr
*, __be16
);
487 int (*is_any
) (const union sctp_addr
*);
488 int (*available
) (union sctp_addr
*,
490 int (*skb_iif
) (const struct sk_buff
*sk
);
491 int (*is_ce
) (const struct sk_buff
*sk
);
492 void (*seq_dump_addr
)(struct seq_file
*seq
,
493 union sctp_addr
*addr
);
494 void (*ecn_capable
)(struct sock
*sk
);
495 __u16 net_header_len
;
497 int (*ip_options_len
)(struct sock
*sk
);
498 sa_family_t sa_family
;
499 struct list_head list
;
502 struct sctp_af
*sctp_get_af_specific(sa_family_t
);
503 int sctp_register_af(struct sctp_af
*);
505 /* Protocol family functions. */
507 void (*event_msgname
)(struct sctp_ulpevent
*, char *, int *);
508 void (*skb_msgname
) (struct sk_buff
*, char *, int *);
509 int (*af_supported
) (sa_family_t
, struct sctp_sock
*);
510 int (*cmp_addr
) (const union sctp_addr
*,
511 const union sctp_addr
*,
513 int (*bind_verify
) (struct sctp_sock
*, union sctp_addr
*);
514 int (*send_verify
) (struct sctp_sock
*, union sctp_addr
*);
515 int (*supported_addrs
)(const struct sctp_sock
*, __be16
*);
516 struct sock
*(*create_accept_sk
) (struct sock
*sk
,
517 struct sctp_association
*asoc
,
519 int (*addr_to_user
)(struct sctp_sock
*sk
, union sctp_addr
*addr
);
520 void (*to_sk_saddr
)(union sctp_addr
*, struct sock
*sk
);
521 void (*to_sk_daddr
)(union sctp_addr
*, struct sock
*sk
);
522 void (*copy_ip_options
)(struct sock
*sk
, struct sock
*newsk
);
527 /* Structure to track chunk fragments that have been acked, but peer
528 * fragments of the same message have not.
530 struct sctp_datamsg
{
531 /* Chunks waiting to be submitted to lower layer. */
532 struct list_head chunks
;
533 /* Reference counting. */
535 /* When is this message no longer interesting to the peer? */
536 unsigned long expires_at
;
537 /* Did the messenge fail to send? */
540 can_delay
:1, /* should this message be Nagle delayed */
541 abandoned
:1; /* should this message be abandoned */
544 struct sctp_datamsg
*sctp_datamsg_from_user(struct sctp_association
*,
545 struct sctp_sndrcvinfo
*,
547 void sctp_datamsg_free(struct sctp_datamsg
*);
548 void sctp_datamsg_put(struct sctp_datamsg
*);
549 void sctp_chunk_fail(struct sctp_chunk
*, int error
);
550 int sctp_chunk_abandoned(struct sctp_chunk
*);
552 /* RFC2960 1.4 Key Terms
554 * o Chunk: A unit of information within an SCTP packet, consisting of
555 * a chunk header and chunk-specific content.
557 * As a matter of convenience, we remember the SCTP common header for
558 * each chunk as well as a few other header pointers...
561 struct list_head list
;
565 /* How many times this chunk have been sent, for prsctp RTX policy */
569 /* This is our link to the per-transport transmitted list. */
570 struct list_head transmitted_list
;
571 /* List in specific stream outq */
572 struct list_head stream_list
;
575 /* This field is used by chunks that hold fragmented data.
576 * For the first fragment this is the list that holds the rest of
577 * fragments. For the remaining fragments, this is the link to the
578 * frag_list maintained in the first fragment.
580 struct list_head frag_list
;
582 /* This points to the sk_buff containing the actual data. */
586 /* In case of GSO packets, this will store the head one */
587 struct sk_buff
*head_skb
;
588 /* In case of auth enabled, this will point to the shkey */
589 struct sctp_shared_key
*shkey
;
592 /* These are the SCTP headers by reverse order in a packet.
593 * Note that some of these may happen more than once. In that
594 * case, we point at the "current" one, whatever that means
595 * for that level of header.
598 /* We point this at the FIRST TLV parameter to chunk_hdr. */
599 union sctp_params param_hdr
;
602 struct sctp_datahdr
*data_hdr
;
603 struct sctp_inithdr
*init_hdr
;
604 struct sctp_sackhdr
*sack_hdr
;
605 struct sctp_heartbeathdr
*hb_hdr
;
606 struct sctp_sender_hb_info
*hbs_hdr
;
607 struct sctp_shutdownhdr
*shutdown_hdr
;
608 struct sctp_signed_cookie
*cookie_hdr
;
609 struct sctp_ecnehdr
*ecne_hdr
;
610 struct sctp_cwrhdr
*ecn_cwr_hdr
;
611 struct sctp_errhdr
*err_hdr
;
612 struct sctp_addiphdr
*addip_hdr
;
613 struct sctp_fwdtsn_hdr
*fwdtsn_hdr
;
614 struct sctp_authhdr
*auth_hdr
;
615 struct sctp_idatahdr
*idata_hdr
;
616 struct sctp_ifwdtsn_hdr
*ifwdtsn_hdr
;
621 struct sctp_chunkhdr
*chunk_hdr
;
622 struct sctphdr
*sctp_hdr
;
624 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
625 struct sctp_sndrcvinfo sinfo
;
627 /* Which association does this belong to? */
628 struct sctp_association
*asoc
;
630 /* What endpoint received this chunk? */
631 struct sctp_ep_common
*rcvr
;
633 /* We fill this in if we are calculating RTT. */
634 unsigned long sent_at
;
636 /* What is the origin IP address for this chunk? */
637 union sctp_addr source
;
638 /* Destination address for this chunk. */
639 union sctp_addr dest
;
641 /* For outbound message, track all fragments for SEND_FAILED. */
642 struct sctp_datamsg
*msg
;
644 /* For an inbound chunk, this tells us where it came from.
645 * For an outbound chunk, it tells us where we'd like it to
646 * go. It is NULL if we have no preference.
648 struct sctp_transport
*transport
;
650 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO
651 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
652 * spec violates the principle premis that all chunks are processed
655 struct sk_buff
*auth_chunk
;
657 #define SCTP_CAN_FRTX 0x0
658 #define SCTP_NEED_FRTX 0x1
659 #define SCTP_DONT_FRTX 0x2
660 __u16 rtt_in_progress
:1, /* This chunk used for RTT calc? */
661 has_tsn
:1, /* Does this chunk have a TSN yet? */
662 has_ssn
:1, /* Does this chunk have a SSN yet? */
663 #define has_mid has_ssn
664 singleton
:1, /* Only chunk in the packet? */
665 end_of_packet
:1, /* Last chunk in the packet? */
666 ecn_ce_done
:1, /* Have we processed the ECN CE bit? */
667 pdiscard
:1, /* Discard the whole packet now? */
668 tsn_gap_acked
:1, /* Is this chunk acked by a GAP ACK? */
669 data_accepted
:1, /* At least 1 chunk accepted */
670 auth
:1, /* IN: was auth'ed | OUT: needs auth */
671 has_asconf
:1, /* IN: have seen an asconf before */
672 tsn_missing_report
:2, /* Data chunk missing counter. */
673 fast_retransmit
:2; /* Is this chunk fast retransmitted? */
676 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1)
677 void sctp_chunk_hold(struct sctp_chunk
*);
678 void sctp_chunk_put(struct sctp_chunk
*);
679 int sctp_user_addto_chunk(struct sctp_chunk
*chunk
, int len
,
680 struct iov_iter
*from
);
681 void sctp_chunk_free(struct sctp_chunk
*);
682 void *sctp_addto_chunk(struct sctp_chunk
*, int len
, const void *data
);
683 struct sctp_chunk
*sctp_chunkify(struct sk_buff
*,
684 const struct sctp_association
*,
685 struct sock
*, gfp_t gfp
);
686 void sctp_init_addrs(struct sctp_chunk
*, union sctp_addr
*,
688 const union sctp_addr
*sctp_source(const struct sctp_chunk
*chunk
);
690 static inline __u16
sctp_chunk_stream_no(struct sctp_chunk
*ch
)
692 return ntohs(ch
->subh
.data_hdr
->stream
);
696 SCTP_ADDR_NEW
, /* new address added to assoc/ep */
697 SCTP_ADDR_SRC
, /* address can be used as source */
698 SCTP_ADDR_DEL
, /* address about to be deleted */
701 /* This is a structure for holding either an IPv6 or an IPv4 address. */
702 struct sctp_sockaddr_entry
{
703 struct list_head list
;
710 #define SCTP_ADDRESS_TICK_DELAY 500
712 /* This structure holds lists of chunks as we are assembling for
716 /* These are the SCTP header values (host order) for the packet. */
718 __u16 destination_port
;
721 /* This contains the payload chunks. */
722 struct list_head chunk_list
;
724 /* This is the overhead of the sctp and ip headers. */
726 /* This is the total size of all chunks INCLUDING padding. */
728 /* This is the maximum size this packet may have */
731 /* The packet is destined for this transport address.
732 * The function we finally use to pass down to the next lower
733 * layer lives in the transport structure.
735 struct sctp_transport
*transport
;
737 /* pointer to the auth chunk for this packet */
738 struct sctp_chunk
*auth
;
740 u8 has_cookie_echo
:1, /* This packet contains a COOKIE-ECHO chunk. */
741 has_sack
:1, /* This packet contains a SACK chunk. */
742 has_auth
:1, /* This packet contains an AUTH chunk */
743 has_data
:1, /* This packet contains at least 1 DATA chunk */
744 ipfragok
:1; /* So let ip fragment this packet */
747 void sctp_packet_init(struct sctp_packet
*, struct sctp_transport
*,
748 __u16 sport
, __u16 dport
);
749 void sctp_packet_config(struct sctp_packet
*, __u32 vtag
, int);
750 enum sctp_xmit
sctp_packet_transmit_chunk(struct sctp_packet
*packet
,
751 struct sctp_chunk
*chunk
,
752 int one_packet
, gfp_t gfp
);
753 enum sctp_xmit
sctp_packet_append_chunk(struct sctp_packet
*packet
,
754 struct sctp_chunk
*chunk
);
755 int sctp_packet_transmit(struct sctp_packet
*, gfp_t
);
756 void sctp_packet_free(struct sctp_packet
*);
758 static inline int sctp_packet_empty(struct sctp_packet
*packet
)
760 return packet
->size
== packet
->overhead
;
763 /* This represents a remote transport address.
764 * For local transport addresses, we just use union sctp_addr.
766 * RFC2960 Section 1.4 Key Terms
768 * o Transport address: A Transport Address is traditionally defined
769 * by Network Layer address, Transport Layer protocol and Transport
770 * Layer port number. In the case of SCTP running over IP, a
771 * transport address is defined by the combination of an IP address
772 * and an SCTP port number (where SCTP is the Transport protocol).
774 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
776 * o The sender keeps a separate congestion control parameter set for
777 * each of the destination addresses it can send to (not each
778 * source-destination pair but for each destination). The parameters
779 * should decay if the address is not used for a long enough time
783 struct sctp_transport
{
784 /* A list of transports. */
785 struct list_head transports
;
786 struct rhlist_head node
;
788 /* Reference counting. */
790 /* RTO-Pending : A flag used to track if one of the DATA
791 * chunks sent to this address is currently being
792 * used to compute a RTT. If this flag is 0,
793 * the next DATA chunk sent to this destination
794 * should be used to compute a RTT and this flag
795 * should be set. Every time the RTT
796 * calculation completes (i.e. the DATA chunk
797 * is SACK'd) clear this flag.
802 * hb_sent : a flag that signals that we have a pending
807 /* Is the Path MTU update pending on this tranport */
810 dst_pending_confirm
:1, /* need to confirm neighbour */
812 /* Has this transport moved the ctsn since we last sacked */
818 /* This is the peer's IP address and port. */
819 union sctp_addr ipaddr
;
821 /* These are the functions we call to handle LLP stuff. */
822 struct sctp_af
*af_specific
;
824 /* Which association do we belong to? */
825 struct sctp_association
*asoc
;
829 * 12.3 Per Transport Address Data
831 * For each destination transport address in the peer's
832 * address list derived from the INIT or INIT ACK chunk, a
833 * number of data elements needs to be maintained including:
835 /* RTO : The current retransmission timeout value. */
838 __u32 rtt
; /* This is the most recent RTT. */
840 /* RTTVAR : The current RTT variation. */
843 /* SRTT : The current smoothed round trip time. */
847 * These are the congestion stats.
849 /* cwnd : The current congestion window. */
850 __u32 cwnd
; /* This is the actual cwnd. */
852 /* ssthresh : The current slow start threshold value. */
855 /* partial : The tracking method for increase of cwnd when in
856 * bytes acked : congestion avoidance mode (see Section 6.2.2)
858 __u32 partial_bytes_acked
;
860 /* Data that has been sent, but not acknowledged. */
863 __u32 burst_limited
; /* Holds old cwnd when max.burst is applied */
866 struct dst_entry
*dst
;
867 /* Source address. */
868 union sctp_addr saddr
;
870 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
871 * the destination address every heartbeat interval.
873 unsigned long hbinterval
;
875 /* SACK delay timeout */
876 unsigned long sackdelay
;
879 /* When was the last time that we heard from this transport? We use
880 * this to pick new active and retran paths.
882 ktime_t last_time_heard
;
884 /* When was the last time that we sent a chunk using this
885 * transport? We use this to check for idle transports
887 unsigned long last_time_sent
;
889 /* Last time(in jiffies) when cwnd is reduced due to the congestion
890 * indication based on ECNE chunk.
892 unsigned long last_time_ecne_reduced
;
894 /* This is the max_retrans value for the transport and will
895 * be initialized from the assocs value. This can be changed
896 * using the SCTP_SET_PEER_ADDR_PARAMS socket option.
903 /* This is the partially failed retrans value for the transport
904 * and will be initialized from the assocs value. This can be changed
905 * using the SCTP_PEER_ADDR_THLDS socket option
908 /* PMTU : The current known path MTU. */
911 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
914 /* The number of times INIT has been sent on this transport. */
917 /* state : The current state of this destination,
918 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
922 /* These are the error stats for this destination. */
924 /* Error count : The current error count for this destination. */
925 unsigned short error_count
;
927 /* Per : A timer used by each destination.
931 * [Everywhere else in the text this is called T3-rtx. -ed]
933 struct timer_list T3_rtx_timer
;
935 /* Heartbeat timer is per destination. */
936 struct timer_list hb_timer
;
938 /* Timer to handle ICMP proto unreachable envets */
939 struct timer_list proto_unreach_timer
;
941 /* Timer to handler reconf chunk rtx */
942 struct timer_list reconf_timer
;
944 /* Since we're using per-destination retransmission timers
945 * (see above), we're also using per-destination "transmitted"
946 * queues. This probably ought to be a private struct
947 * accessible only within the outqueue, but it's not, yet.
949 struct list_head transmitted
;
951 /* We build bundle-able packets for this transport here. */
952 struct sctp_packet packet
;
954 /* This is the list of transports that have chunks to send. */
955 struct list_head send_ready
;
957 /* State information saved for SFR_CACC algorithm. The key
958 * idea in SFR_CACC is to maintain state at the sender on a
959 * per-destination basis when a changeover happens.
960 * char changeover_active;
961 * char cycling_changeover;
962 * __u32 next_tsn_at_change;
963 * char cacc_saw_newack;
966 /* An unsigned integer, which stores the next TSN to be
967 * used by the sender, at the moment of changeover.
969 __u32 next_tsn_at_change
;
971 /* A flag which indicates the occurrence of a changeover */
972 char changeover_active
;
974 /* A flag which indicates whether the change of primary is
975 * the first switch to this destination address during an
978 char cycling_changeover
;
980 /* A temporary flag, which is used during the processing of
981 * a SACK to estimate the causative TSN(s)'s group.
983 char cacc_saw_newack
;
986 /* 64-bit random number sent with heartbeat. */
992 struct sctp_transport
*sctp_transport_new(struct net
*, const union sctp_addr
*,
994 void sctp_transport_set_owner(struct sctp_transport
*,
995 struct sctp_association
*);
996 void sctp_transport_route(struct sctp_transport
*, union sctp_addr
*,
998 void sctp_transport_pmtu(struct sctp_transport
*, struct sock
*sk
);
999 void sctp_transport_free(struct sctp_transport
*);
1000 void sctp_transport_reset_t3_rtx(struct sctp_transport
*);
1001 void sctp_transport_reset_hb_timer(struct sctp_transport
*);
1002 void sctp_transport_reset_reconf_timer(struct sctp_transport
*transport
);
1003 int sctp_transport_hold(struct sctp_transport
*);
1004 void sctp_transport_put(struct sctp_transport
*);
1005 void sctp_transport_update_rto(struct sctp_transport
*, __u32
);
1006 void sctp_transport_raise_cwnd(struct sctp_transport
*, __u32
, __u32
);
1007 void sctp_transport_lower_cwnd(struct sctp_transport
*t
,
1008 enum sctp_lower_cwnd reason
);
1009 void sctp_transport_burst_limited(struct sctp_transport
*);
1010 void sctp_transport_burst_reset(struct sctp_transport
*);
1011 unsigned long sctp_transport_timeout(struct sctp_transport
*);
1012 void sctp_transport_reset(struct sctp_transport
*t
);
1013 bool sctp_transport_update_pmtu(struct sctp_transport
*t
, u32 pmtu
);
1014 void sctp_transport_immediate_rtx(struct sctp_transport
*);
1015 void sctp_transport_dst_release(struct sctp_transport
*t
);
1016 void sctp_transport_dst_confirm(struct sctp_transport
*t
);
1019 /* This is the structure we use to queue packets as they come into
1020 * SCTP. We write packets to it and read chunks from it.
1023 /* This is actually a queue of sctp_chunk each
1024 * containing a partially decoded packet.
1026 struct list_head in_chunk_list
;
1027 /* This is the packet which is currently off the in queue and is
1028 * being worked on through the inbound chunk processing.
1030 struct sctp_chunk
*in_progress
;
1032 /* This is the delayed task to finish delivering inbound
1035 struct work_struct immediate
;
1038 void sctp_inq_init(struct sctp_inq
*);
1039 void sctp_inq_free(struct sctp_inq
*);
1040 void sctp_inq_push(struct sctp_inq
*, struct sctp_chunk
*packet
);
1041 struct sctp_chunk
*sctp_inq_pop(struct sctp_inq
*);
1042 struct sctp_chunkhdr
*sctp_inq_peek(struct sctp_inq
*);
1043 void sctp_inq_set_th_handler(struct sctp_inq
*, work_func_t
);
1045 /* This is the structure we use to hold outbound chunks. You push
1046 * chunks in and they automatically pop out the other end as bundled
1047 * packets (it calls (*output_handler)()).
1049 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1050 * and 8.2 of the v13 draft.
1052 * It handles retransmissions. The connection to the timeout portion
1053 * of the state machine is through sctp_..._timeout() and timeout_handler.
1055 * If you feed it SACKs, it will eat them.
1057 * If you give it big chunks, it will fragment them.
1059 * It assigns TSN's to data chunks. This happens at the last possible
1060 * instant before transmission.
1062 * When free()'d, it empties itself out via output_handler().
1065 struct sctp_association
*asoc
;
1067 /* Data pending that has never been transmitted. */
1068 struct list_head out_chunk_list
;
1070 /* Stream scheduler being used */
1071 struct sctp_sched_ops
*sched
;
1073 unsigned int out_qlen
; /* Total length of queued data chunks. */
1075 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1078 /* These are control chunks we want to send. */
1079 struct list_head control_chunk_list
;
1081 /* These are chunks that have been sacked but are above the
1082 * CTSN, or cumulative tsn ack point.
1084 struct list_head sacked
;
1086 /* Put chunks on this list to schedule them for
1089 struct list_head retransmit
;
1091 /* Put chunks on this list to save them for FWD TSN processing as
1092 * they were abandoned.
1094 struct list_head abandoned
;
1096 /* How many unackd bytes do we have in-flight? */
1097 __u32 outstanding_bytes
;
1099 /* Are we doing fast-rtx on this queue */
1106 void sctp_outq_init(struct sctp_association
*, struct sctp_outq
*);
1107 void sctp_outq_teardown(struct sctp_outq
*);
1108 void sctp_outq_free(struct sctp_outq
*);
1109 void sctp_outq_tail(struct sctp_outq
*, struct sctp_chunk
*chunk
, gfp_t
);
1110 int sctp_outq_sack(struct sctp_outq
*, struct sctp_chunk
*);
1111 int sctp_outq_is_empty(const struct sctp_outq
*);
1112 void sctp_outq_restart(struct sctp_outq
*);
1114 void sctp_retransmit(struct sctp_outq
*q
, struct sctp_transport
*transport
,
1115 enum sctp_retransmit_reason reason
);
1116 void sctp_retransmit_mark(struct sctp_outq
*, struct sctp_transport
*, __u8
);
1117 void sctp_outq_uncork(struct sctp_outq
*, gfp_t gfp
);
1118 void sctp_prsctp_prune(struct sctp_association
*asoc
,
1119 struct sctp_sndrcvinfo
*sinfo
, int msg_len
);
1120 void sctp_generate_fwdtsn(struct sctp_outq
*q
, __u32 sack_ctsn
);
1121 /* Uncork and flush an outqueue. */
1122 static inline void sctp_outq_cork(struct sctp_outq
*q
)
1127 /* SCTP skb control block.
1128 * sctp_input_cb is currently used on rx and sock rx queue
1130 struct sctp_input_cb
{
1132 struct inet_skb_parm h4
;
1133 #if IS_ENABLED(CONFIG_IPV6)
1134 struct inet6_skb_parm h6
;
1137 struct sctp_chunk
*chunk
;
1140 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0]))
1142 struct sctp_output_cb
{
1143 struct sk_buff
*last
;
1145 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0]))
1147 static inline const struct sk_buff
*sctp_gso_headskb(const struct sk_buff
*skb
)
1149 const struct sctp_chunk
*chunk
= SCTP_INPUT_CB(skb
)->chunk
;
1151 return chunk
->head_skb
? : skb
;
1154 /* These bind address data fields common between endpoints and associations */
1155 struct sctp_bind_addr
{
1157 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1159 * SCTP Port: The local SCTP port number the endpoint is
1164 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1166 * Address List: The list of IP addresses that this instance
1167 * has bound. This information is passed to one's
1168 * peer(s) in INIT and INIT ACK chunks.
1170 struct list_head address_list
;
1173 void sctp_bind_addr_init(struct sctp_bind_addr
*, __u16 port
);
1174 void sctp_bind_addr_free(struct sctp_bind_addr
*);
1175 int sctp_bind_addr_copy(struct net
*net
, struct sctp_bind_addr
*dest
,
1176 const struct sctp_bind_addr
*src
,
1177 enum sctp_scope scope
, gfp_t gfp
,
1179 int sctp_bind_addr_dup(struct sctp_bind_addr
*dest
,
1180 const struct sctp_bind_addr
*src
,
1182 int sctp_add_bind_addr(struct sctp_bind_addr
*, union sctp_addr
*,
1183 int new_size
, __u8 addr_state
, gfp_t gfp
);
1184 int sctp_del_bind_addr(struct sctp_bind_addr
*, union sctp_addr
*);
1185 int sctp_bind_addr_match(struct sctp_bind_addr
*, const union sctp_addr
*,
1186 struct sctp_sock
*);
1187 int sctp_bind_addr_conflict(struct sctp_bind_addr
*, const union sctp_addr
*,
1188 struct sctp_sock
*, struct sctp_sock
*);
1189 int sctp_bind_addr_state(const struct sctp_bind_addr
*bp
,
1190 const union sctp_addr
*addr
);
1191 union sctp_addr
*sctp_find_unmatch_addr(struct sctp_bind_addr
*bp
,
1192 const union sctp_addr
*addrs
,
1194 struct sctp_sock
*opt
);
1195 union sctp_params
sctp_bind_addrs_to_raw(const struct sctp_bind_addr
*bp
,
1198 int sctp_raw_to_bind_addrs(struct sctp_bind_addr
*bp
, __u8
*raw
, int len
,
1199 __u16 port
, gfp_t gfp
);
1201 enum sctp_scope
sctp_scope(const union sctp_addr
*addr
);
1202 int sctp_in_scope(struct net
*net
, const union sctp_addr
*addr
,
1203 const enum sctp_scope scope
);
1204 int sctp_is_any(struct sock
*sk
, const union sctp_addr
*addr
);
1205 int sctp_is_ep_boundall(struct sock
*sk
);
1208 /* What type of endpoint? */
1209 enum sctp_endpoint_type
{
1210 SCTP_EP_TYPE_SOCKET
,
1211 SCTP_EP_TYPE_ASSOCIATION
,
1215 * A common base class to bridge the implmentation view of a
1216 * socket (usually listening) endpoint versus an association's
1218 * This common structure is useful for several purposes:
1219 * 1) Common interface for lookup routines.
1220 * a) Subfunctions work for either endpoint or association
1221 * b) Single interface to lookup allows hiding the lookup lock rather
1222 * than acquiring it externally.
1223 * 2) Common interface for the inbound chunk handling/state machine.
1224 * 3) Common object handling routines for reference counting, etc.
1225 * 4) Disentangle association lookup from endpoint lookup, where we
1226 * do not have to find our endpoint to find our association.
1230 struct sctp_ep_common
{
1231 /* Fields to help us manage our entries in the hash tables. */
1232 struct hlist_node node
;
1235 /* Runtime type information. What kind of endpoint is this? */
1236 enum sctp_endpoint_type type
;
1238 /* Some fields to help us manage this object.
1239 * refcnt - Reference count access to this object.
1240 * dead - Do not attempt to use this object.
1245 /* What socket does this endpoint belong to? */
1248 /* This is where we receive inbound chunks. */
1249 struct sctp_inq inqueue
;
1251 /* This substructure includes the defining parameters of the
1253 * bind_addr.port is our shared port number.
1254 * bind_addr.address_list is our set of local IP addresses.
1256 struct sctp_bind_addr bind_addr
;
1260 /* RFC Section 1.4 Key Terms
1262 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1263 * multi-homed host, an SCTP endpoint is represented to its peers as a
1264 * combination of a set of eligible destination transport addresses to
1265 * which SCTP packets can be sent and a set of eligible source
1266 * transport addresses from which SCTP packets can be received.
1267 * All transport addresses used by an SCTP endpoint must use the
1268 * same port number, but can use multiple IP addresses. A transport
1269 * address used by an SCTP endpoint must not be used by another
1270 * SCTP endpoint. In other words, a transport address is unique
1271 * to an SCTP endpoint.
1273 * From an implementation perspective, each socket has one of these.
1274 * A TCP-style socket will have exactly one association on one of
1275 * these. An UDP-style socket will have multiple associations hanging
1279 struct sctp_endpoint
{
1280 /* Common substructure for endpoint and association. */
1281 struct sctp_ep_common base
;
1283 /* Associations: A list of current associations and mappings
1284 * to the data consumers for each association. This
1285 * may be in the form of a hash table or other
1286 * implementation dependent structure. The data
1287 * consumers may be process identification
1288 * information such as file descriptors, named pipe
1289 * pointer, or table pointers dependent on how SCTP
1292 /* This is really a list of struct sctp_association entries. */
1293 struct list_head asocs
;
1295 /* Secret Key: A secret key used by this endpoint to compute
1296 * the MAC. This SHOULD be a cryptographic quality
1297 * random number with a sufficient length.
1298 * Discussion in [RFC1750] can be helpful in
1299 * selection of the key.
1301 __u8 secret_key
[SCTP_SECRET_SIZE
];
1303 /* digest: This is a digest of the sctp cookie. This field is
1304 * only used on the receive path when we try to validate
1305 * that the cookie has not been tampered with. We put
1306 * this here so we pre-allocate this once and can re-use
1311 /* sendbuf acct. policy. */
1312 __u32 sndbuf_policy
;
1314 /* rcvbuf acct. policy. */
1315 __u32 rcvbuf_policy
;
1317 /* SCTP AUTH: array of the HMACs that will be allocated
1318 * we need this per association so that we don't serialize
1320 struct crypto_shash
**auth_hmacs
;
1322 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1323 struct sctp_hmac_algo_param
*auth_hmacs_list
;
1325 /* SCTP-AUTH: chunks to authenticate encoded into parameter */
1326 struct sctp_chunks_param
*auth_chunk_list
;
1328 /* SCTP-AUTH: endpoint shared keys */
1329 struct list_head endpoint_shared_keys
;
1330 __u16 active_key_id
;
1335 __u8 strreset_enable
;
1337 /* Security identifiers from incoming (INIT). These are set by
1338 * security_sctp_assoc_request(). These will only be used by
1339 * SCTP TCP type sockets and peeled off connections as they
1340 * cause a new socket to be generated. security_sctp_sk_clone()
1341 * will then plug these into the new socket.
1348 /* Recover the outter endpoint structure. */
1349 static inline struct sctp_endpoint
*sctp_ep(struct sctp_ep_common
*base
)
1351 struct sctp_endpoint
*ep
;
1353 ep
= container_of(base
, struct sctp_endpoint
, base
);
1357 /* These are function signatures for manipulating endpoints. */
1358 struct sctp_endpoint
*sctp_endpoint_new(struct sock
*, gfp_t
);
1359 void sctp_endpoint_free(struct sctp_endpoint
*);
1360 void sctp_endpoint_put(struct sctp_endpoint
*);
1361 void sctp_endpoint_hold(struct sctp_endpoint
*);
1362 void sctp_endpoint_add_asoc(struct sctp_endpoint
*, struct sctp_association
*);
1363 struct sctp_association
*sctp_endpoint_lookup_assoc(
1364 const struct sctp_endpoint
*ep
,
1365 const union sctp_addr
*paddr
,
1366 struct sctp_transport
**);
1367 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint
*ep
,
1368 const union sctp_addr
*paddr
);
1369 struct sctp_endpoint
*sctp_endpoint_is_match(struct sctp_endpoint
*,
1370 struct net
*, const union sctp_addr
*);
1371 bool sctp_has_association(struct net
*net
, const union sctp_addr
*laddr
,
1372 const union sctp_addr
*paddr
);
1374 int sctp_verify_init(struct net
*net
, const struct sctp_endpoint
*ep
,
1375 const struct sctp_association
*asoc
,
1376 enum sctp_cid cid
, struct sctp_init_chunk
*peer_init
,
1377 struct sctp_chunk
*chunk
, struct sctp_chunk
**err_chunk
);
1378 int sctp_process_init(struct sctp_association
*, struct sctp_chunk
*chunk
,
1379 const union sctp_addr
*peer
,
1380 struct sctp_init_chunk
*init
, gfp_t gfp
);
1381 __u32
sctp_generate_tag(const struct sctp_endpoint
*);
1382 __u32
sctp_generate_tsn(const struct sctp_endpoint
*);
1384 struct sctp_inithdr_host
{
1387 __u16 num_outbound_streams
;
1388 __u16 num_inbound_streams
;
1392 struct sctp_stream_priorities
{
1393 /* List of priorities scheduled */
1394 struct list_head prio_sched
;
1395 /* List of streams scheduled */
1396 struct list_head active
;
1397 /* The next stream stream in line */
1398 struct sctp_stream_out_ext
*next
;
1402 struct sctp_stream_out_ext
{
1403 __u64 abandoned_unsent
[SCTP_PR_INDEX(MAX
) + 1];
1404 __u64 abandoned_sent
[SCTP_PR_INDEX(MAX
) + 1];
1405 struct list_head outq
; /* chunks enqueued by this stream */
1408 /* Scheduled streams list */
1409 struct list_head prio_list
;
1410 struct sctp_stream_priorities
*prio_head
;
1412 /* Fields used by RR scheduler */
1414 struct list_head rr_list
;
1419 struct sctp_stream_out
{
1425 struct sctp_stream_out_ext
*ext
;
1429 struct sctp_stream_in
{
1441 struct sctp_stream
{
1442 struct flex_array
*out
;
1443 struct flex_array
*in
;
1446 /* Current stream being sent, if any */
1447 struct sctp_stream_out
*out_curr
;
1449 /* Fields used by priority scheduler */
1451 /* List of priorities scheduled */
1452 struct list_head prio_list
;
1454 /* Fields used by RR scheduler */
1456 /* List of streams scheduled */
1457 struct list_head rr_list
;
1458 /* The next stream stream in line */
1459 struct sctp_stream_out_ext
*rr_next
;
1462 struct sctp_stream_interleave
*si
;
1465 static inline struct sctp_stream_out
*sctp_stream_out(
1466 const struct sctp_stream
*stream
,
1469 return flex_array_get(stream
->out
, sid
);
1472 static inline struct sctp_stream_in
*sctp_stream_in(
1473 const struct sctp_stream
*stream
,
1476 return flex_array_get(stream
->in
, sid
);
1479 #define SCTP_SO(s, i) sctp_stream_out((s), (i))
1480 #define SCTP_SI(s, i) sctp_stream_in((s), (i))
1482 #define SCTP_STREAM_CLOSED 0x00
1483 #define SCTP_STREAM_OPEN 0x01
1485 static inline __u16
sctp_datachk_len(const struct sctp_stream
*stream
)
1487 return stream
->si
->data_chunk_len
;
1490 static inline __u16
sctp_datahdr_len(const struct sctp_stream
*stream
)
1492 return stream
->si
->data_chunk_len
- sizeof(struct sctp_chunkhdr
);
1495 static inline __u16
sctp_ftsnchk_len(const struct sctp_stream
*stream
)
1497 return stream
->si
->ftsn_chunk_len
;
1500 static inline __u16
sctp_ftsnhdr_len(const struct sctp_stream
*stream
)
1502 return stream
->si
->ftsn_chunk_len
- sizeof(struct sctp_chunkhdr
);
1505 /* SCTP_GET_ASSOC_STATS counters */
1506 struct sctp_priv_assoc_stats
{
1507 /* Maximum observed rto in the association during subsequent
1508 * observations. Value is set to 0 if no RTO measurement took place
1509 * The transport where the max_rto was observed is returned in
1512 struct sockaddr_storage obs_rto_ipaddr
;
1514 /* Total In and Out SACKs received and sent */
1517 /* Total In and Out packets received and sent */
1520 /* Total retransmitted chunks */
1522 /* TSN received > next expected */
1524 /* Duplicate Chunks received */
1526 /* Gap Ack Blocks received */
1528 /* Unordered data chunks sent and received */
1531 /* Ordered data chunks sent and received */
1534 /* Control chunks sent and received */
1541 * 12. Recommended Transmission Control Block (TCB) Parameters
1543 * This section details a recommended set of parameters that should
1544 * be contained within the TCB for an implementation. This section is
1545 * for illustrative purposes and should not be deemed as requirements
1546 * on an implementation or as an exhaustive list of all parameters
1547 * inside an SCTP TCB. Each implementation may need its own additional
1548 * parameters for optimization.
1552 /* Here we have information about each individual association. */
1553 struct sctp_association
{
1555 /* A base structure common to endpoint and association.
1556 * In this context, it represents the associations's view
1557 * of the local endpoint of the association.
1559 struct sctp_ep_common base
;
1561 /* Associations on the same socket. */
1562 struct list_head asocs
;
1564 /* association id. */
1565 sctp_assoc_t assoc_id
;
1567 /* This is our parent endpoint. */
1568 struct sctp_endpoint
*ep
;
1570 /* These are those association elements needed in the cookie. */
1571 struct sctp_cookie c
;
1573 /* This is all information about our peer. */
1575 /* transport_addr_list
1577 * Peer : A list of SCTP transport addresses that the
1578 * Transport : peer is bound to. This information is derived
1579 * Address : from the INIT or INIT ACK and is used to
1580 * List : associate an inbound packet with a given
1581 * : association. Normally this information is
1582 * : hashed or keyed for quick lookup and access
1584 * : The list is also initialized with the list
1585 * : of addresses passed with the sctp_connectx()
1588 * It is a list of SCTP_transport's.
1590 struct list_head transport_addr_list
;
1594 * Peer Rwnd : Current calculated value of the peer's rwnd.
1600 * Peer : A count of the number of peer addresses
1601 * Transport : in the Peer Transport Address List.
1605 __u16 transport_count
;
1608 * The transport layer port number.
1614 * Primary : This is the current primary destination
1615 * Path : transport address of the peer endpoint. It
1616 * : may also specify a source transport address
1617 * : on this endpoint.
1619 * All of these paths live on transport_addr_list.
1621 * At the bakeoffs, we discovered that the intent of
1622 * primaryPath is that it only changes when the ULP
1623 * asks to have it changed. We add the activePath to
1624 * designate the connection we are currently using to
1625 * transmit new data and most control chunks.
1627 struct sctp_transport
*primary_path
;
1629 /* Cache the primary path address here, when we
1630 * need a an address for msg_name.
1632 union sctp_addr primary_addr
;
1635 * The path that we are currently using to
1636 * transmit new data and most control chunks.
1638 struct sctp_transport
*active_path
;
1642 * RFC2960 6.4 Multi-homed SCTP Endpoints
1644 * Furthermore, when its peer is multi-homed, an
1645 * endpoint SHOULD try to retransmit a chunk to an
1646 * active destination transport address that is
1647 * different from the last destination address to
1648 * which the DATA chunk was sent.
1650 struct sctp_transport
*retran_path
;
1652 /* Pointer to last transport I have sent on. */
1653 struct sctp_transport
*last_sent_to
;
1655 /* This is the last transport I have received DATA on. */
1656 struct sctp_transport
*last_data_from
;
1659 * Mapping An array of bits or bytes indicating which out of
1660 * Array order TSN's have been received (relative to the
1661 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1662 * order packets have been received, this array
1663 * will be set to all zero. This structure may be
1664 * in the form of a circular buffer or bit array.
1666 * Last Rcvd : This is the last TSN received in
1667 * TSN : sequence. This value is set initially by
1668 * : taking the peer's Initial TSN, received in
1669 * : the INIT or INIT ACK chunk, and subtracting
1672 * Throughout most of the specification this is called the
1673 * "Cumulative TSN ACK Point". In this case, we
1674 * ignore the advice in 12.2 in favour of the term
1675 * used in the bulk of the text. This value is hidden
1676 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1678 struct sctp_tsnmap tsn_map
;
1680 /* This mask is used to disable sending the ASCONF chunk
1681 * with specified parameter to peer.
1683 __be16 addip_disabled_mask
;
1685 /* These are capabilities which our peer advertised. */
1686 __u8 ecn_capable
:1, /* Can peer do ECN? */
1687 ipv4_address
:1, /* Peer understands IPv4 addresses? */
1688 ipv6_address
:1, /* Peer understands IPv6 addresses? */
1689 hostname_address
:1, /* Peer understands DNS addresses? */
1690 asconf_capable
:1, /* Does peer support ADDIP? */
1691 prsctp_capable
:1, /* Can peer do PR-SCTP? */
1692 reconf_capable
:1, /* Can peer do RE-CONFIG? */
1693 auth_capable
:1; /* Is peer doing SCTP-AUTH? */
1695 /* sack_needed : This flag indicates if the next received
1696 * : packet is to be responded to with a
1697 * : SACK. This is initialized to 0. When a packet
1698 * : is received sack_cnt is incremented. If this value
1699 * : reaches 2 or more, a SACK is sent and the
1700 * : value is reset to 0. Note: This is used only
1701 * : when no DATA chunks are received out of
1702 * : order. When DATA chunks are out of order,
1703 * : SACK's are not delayed (see Section 6).
1705 __u8 sack_needed
:1, /* Do we need to sack the peer? */
1707 zero_window_announced
:1;
1710 __u32 adaptation_ind
; /* Adaptation Code point. */
1712 struct sctp_inithdr_host i
;
1716 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1717 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1718 * Initial TSN Value minus 1
1722 /* SCTP-AUTH: We need to know pears random number, hmac list
1723 * and authenticated chunk list. All that is part of the
1724 * cookie and these are just pointers to those locations
1726 struct sctp_random_param
*peer_random
;
1727 struct sctp_chunks_param
*peer_chunks
;
1728 struct sctp_hmac_algo_param
*peer_hmacs
;
1731 /* State : A state variable indicating what state the
1732 * : association is in, i.e. COOKIE-WAIT,
1733 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1734 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1736 * Note: No "CLOSED" state is illustrated since if a
1737 * association is "CLOSED" its TCB SHOULD be removed.
1739 * In this implementation we DO have a CLOSED
1740 * state which is used during initiation and shutdown.
1742 * State takes values from SCTP_STATE_*.
1744 enum sctp_state state
;
1746 /* Overall : The overall association error count.
1747 * Error Count : [Clear this any time I get something.]
1749 int overall_error_count
;
1751 /* The cookie life I award for any cookie. */
1752 ktime_t cookie_life
;
1754 /* These are the association's initial, max, and min RTO values.
1755 * These values will be initialized by system defaults, but can
1756 * be modified via the SCTP_RTOINFO socket option.
1758 unsigned long rto_initial
;
1759 unsigned long rto_max
;
1760 unsigned long rto_min
;
1762 /* Maximum number of new data packets that can be sent in a burst. */
1765 /* This is the max_retrans value for the association. This value will
1766 * be initialized initialized from system defaults, but can be
1767 * modified by the SCTP_ASSOCINFO socket option.
1771 /* This is the partially failed retrans value for the transport
1772 * and will be initialized from the assocs value. This can be
1773 * changed using the SCTP_PEER_ADDR_THLDS socket option
1777 /* Maximum number of times the endpoint will retransmit INIT */
1778 __u16 max_init_attempts
;
1780 /* How many times have we resent an INIT? */
1783 /* The largest timeout or RTO value to use in attempting an INIT */
1784 unsigned long max_init_timeo
;
1786 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1787 * the destination address every heartbeat interval. This value
1788 * will be inherited by all new transports.
1790 unsigned long hbinterval
;
1792 /* This is the max_retrans value for new transports in the
1800 /* Flag that path mtu update is pending */
1803 /* Association : The smallest PMTU discovered for all of the
1804 * PMTU : peer's transport addresses.
1808 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1812 /* SACK delay timeout */
1813 unsigned long sackdelay
;
1815 unsigned long timeouts
[SCTP_NUM_TIMEOUT_TYPES
];
1816 struct timer_list timers
[SCTP_NUM_TIMEOUT_TYPES
];
1818 /* Transport to which SHUTDOWN chunk was last sent. */
1819 struct sctp_transport
*shutdown_last_sent_to
;
1821 /* Transport to which INIT chunk was last sent. */
1822 struct sctp_transport
*init_last_sent_to
;
1824 /* How many times have we resent a SHUTDOWN */
1825 int shutdown_retries
;
1827 /* Next TSN : The next TSN number to be assigned to a new
1828 * : DATA chunk. This is sent in the INIT or INIT
1829 * : ACK chunk to the peer and incremented each
1830 * : time a DATA chunk is assigned a TSN
1831 * : (normally just prior to transmit or during
1837 * Last Rcvd : This is the last TSN received in sequence. This value
1838 * TSN : is set initially by taking the peer's Initial TSN,
1839 * : received in the INIT or INIT ACK chunk, and
1840 * : subtracting one from it.
1842 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1845 __u32 ctsn_ack_point
;
1847 /* PR-SCTP Advanced.Peer.Ack.Point */
1848 __u32 adv_peer_ack_point
;
1850 /* Highest TSN that is acknowledged by incoming SACKs. */
1851 __u32 highest_sacked
;
1853 /* TSN marking the fast recovery exit point */
1854 __u32 fast_recovery_exit
;
1856 /* Flag to track the current fast recovery state */
1859 /* The number of unacknowledged data chunks. Reported through
1860 * the SCTP_STATUS sockopt.
1864 /* The total number of data chunks that we've had to retransmit
1865 * as the result of a T3 timer expiration
1867 __u32 rtx_data_chunks
;
1869 /* This is the association's receive buffer space. This value is used
1870 * to set a_rwnd field in an INIT or a SACK chunk.
1874 /* This is the last advertised value of rwnd over a SACK chunk. */
1877 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1878 * to slop over a maximum of the association's frag_point.
1882 /* Keeps treack of rwnd pressure. This happens when we have
1883 * a window, but not recevie buffer (i.e small packets). This one
1884 * is releases slowly (1 PMTU at a time ).
1888 /* This is the sndbuf size in use for the association.
1889 * This corresponds to the sndbuf size for the association,
1890 * as specified in the sk->sndbuf.
1894 /* This is the amount of memory that this association has allocated
1895 * in the receive path at any given time.
1897 atomic_t rmem_alloc
;
1899 /* This is the wait queue head for send requests waiting on
1900 * the association sndbuf space.
1902 wait_queue_head_t wait
;
1904 /* The message size at which SCTP fragmentation will occur. */
1908 /* Counter used to count INIT errors. */
1909 int init_err_counter
;
1911 /* Count the number of INIT cycles (for doubling timeout). */
1914 /* Default send parameters. */
1915 __u16 default_stream
;
1916 __u16 default_flags
;
1918 __u32 default_context
;
1919 __u32 default_timetolive
;
1921 /* Default receive parameters */
1922 __u32 default_rcv_context
;
1925 struct sctp_stream stream
;
1927 /* All outbound chunks go through this structure. */
1928 struct sctp_outq outqueue
;
1930 /* A smart pipe that will handle reordering and fragmentation,
1931 * as well as handle passing events up to the ULP.
1933 struct sctp_ulpq ulpq
;
1935 /* Last TSN that caused an ECNE Chunk to be sent. */
1936 __u32 last_ecne_tsn
;
1938 /* Last TSN that caused a CWR Chunk to be sent. */
1941 /* How many duplicated TSNs have we seen? */
1944 /* These are to support
1945 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1946 * and Enforcement of Flow and Message Limits"
1947 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1948 * or "ADDIP" for short.
1953 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1955 * R1) One and only one ASCONF Chunk MAY be in transit and
1956 * unacknowledged at any one time. If a sender, after sending
1957 * an ASCONF chunk, decides it needs to transfer another
1958 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1959 * returns from the previous ASCONF Chunk before sending a
1960 * subsequent ASCONF. Note this restriction binds each side,
1961 * so at any time two ASCONF may be in-transit on any given
1962 * association (one sent from each endpoint).
1964 * [This is our one-and-only-one ASCONF in flight. If we do
1965 * not have an ASCONF in flight, this is NULL.]
1967 struct sctp_chunk
*addip_last_asconf
;
1969 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
1971 * This is needed to implement itmes E1 - E4 of the updated
1972 * spec. Here is the justification:
1974 * Since the peer may bundle multiple ASCONF chunks toward us,
1975 * we now need the ability to cache multiple ACKs. The section
1976 * describes in detail how they are cached and cleaned up.
1978 struct list_head asconf_ack_list
;
1980 /* These ASCONF chunks are waiting to be sent.
1982 * These chunaks can't be pushed to outqueue until receiving
1983 * ASCONF_ACK for the previous ASCONF indicated by
1984 * addip_last_asconf, so as to guarantee that only one ASCONF
1985 * is in flight at any time.
1987 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1989 * In defining the ASCONF Chunk transfer procedures, it is
1990 * essential that these transfers MUST NOT cause congestion
1991 * within the network. To achieve this, we place these
1992 * restrictions on the transfer of ASCONF Chunks:
1994 * R1) One and only one ASCONF Chunk MAY be in transit and
1995 * unacknowledged at any one time. If a sender, after sending
1996 * an ASCONF chunk, decides it needs to transfer another
1997 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1998 * returns from the previous ASCONF Chunk before sending a
1999 * subsequent ASCONF. Note this restriction binds each side,
2000 * so at any time two ASCONF may be in-transit on any given
2001 * association (one sent from each endpoint).
2004 * [I really think this is EXACTLY the sort of intelligence
2005 * which already resides in sctp_outq. Please move this
2006 * queue and its supporting logic down there. --piggy]
2008 struct list_head addip_chunk_list
;
2010 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2012 * A2) A serial number should be assigned to the Chunk. The
2013 * serial number SHOULD be a monotonically increasing
2014 * number. The serial number SHOULD be initialized at
2015 * the start of the association to the same value as the
2016 * Initial TSN and every time a new ASCONF chunk is created
2017 * it is incremented by one after assigning the serial number
2018 * to the newly created chunk.
2021 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
2023 * Serial Number : 32 bits (unsigned integer)
2025 * This value represents a Serial Number for the ASCONF
2026 * Chunk. The valid range of Serial Number is from 0 to
2027 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
2028 * after reaching 4294967295.
2031 int src_out_of_asoc_ok
;
2032 union sctp_addr
*asconf_addr_del_pending
;
2033 struct sctp_transport
*new_transport
;
2035 /* SCTP AUTH: list of the endpoint shared keys. These
2036 * keys are provided out of band by the user applicaton
2037 * and can't change during the lifetime of the association
2039 struct list_head endpoint_shared_keys
;
2042 * The current generated assocaition shared key (secret)
2044 struct sctp_auth_bytes
*asoc_shared_key
;
2045 struct sctp_shared_key
*shkey
;
2047 /* SCTP AUTH: hmac id of the first peer requested algorithm
2050 __u16 default_hmac_id
;
2052 __u16 active_key_id
;
2054 __u8 need_ecne
:1, /* Need to send an ECNE Chunk? */
2055 temp
:1, /* Is it a temporary association? */
2061 __u8 strreset_enable
;
2062 __u8 strreset_outstanding
; /* request param count on the fly */
2064 __u32 strreset_outseq
; /* Update after receiving response */
2065 __u32 strreset_inseq
; /* Update after receiving request */
2066 __u32 strreset_result
[2]; /* save the results of last 2 responses */
2068 struct sctp_chunk
*strreset_chunk
; /* save request chunk */
2070 struct sctp_priv_assoc_stats stats
;
2072 int sent_cnt_removable
;
2074 __u64 abandoned_unsent
[SCTP_PR_INDEX(MAX
) + 1];
2075 __u64 abandoned_sent
[SCTP_PR_INDEX(MAX
) + 1];
2079 /* An eyecatcher for determining if we are really looking at an
2080 * association data structure.
2083 SCTP_ASSOC_EYECATCHER
= 0xa550c123,
2086 /* Recover the outter association structure. */
2087 static inline struct sctp_association
*sctp_assoc(struct sctp_ep_common
*base
)
2089 struct sctp_association
*asoc
;
2091 asoc
= container_of(base
, struct sctp_association
, base
);
2095 /* These are function signatures for manipulating associations. */
2098 struct sctp_association
*
2099 sctp_association_new(const struct sctp_endpoint
*ep
, const struct sock
*sk
,
2100 enum sctp_scope scope
, gfp_t gfp
);
2101 void sctp_association_free(struct sctp_association
*);
2102 void sctp_association_put(struct sctp_association
*);
2103 void sctp_association_hold(struct sctp_association
*);
2105 struct sctp_transport
*sctp_assoc_choose_alter_transport(
2106 struct sctp_association
*, struct sctp_transport
*);
2107 void sctp_assoc_update_retran_path(struct sctp_association
*);
2108 struct sctp_transport
*sctp_assoc_lookup_paddr(const struct sctp_association
*,
2109 const union sctp_addr
*);
2110 int sctp_assoc_lookup_laddr(struct sctp_association
*asoc
,
2111 const union sctp_addr
*laddr
);
2112 struct sctp_transport
*sctp_assoc_add_peer(struct sctp_association
*,
2113 const union sctp_addr
*address
,
2115 const int peer_state
);
2116 void sctp_assoc_del_peer(struct sctp_association
*asoc
,
2117 const union sctp_addr
*addr
);
2118 void sctp_assoc_rm_peer(struct sctp_association
*asoc
,
2119 struct sctp_transport
*peer
);
2120 void sctp_assoc_control_transport(struct sctp_association
*asoc
,
2121 struct sctp_transport
*transport
,
2122 enum sctp_transport_cmd command
,
2123 sctp_sn_error_t error
);
2124 struct sctp_transport
*sctp_assoc_lookup_tsn(struct sctp_association
*, __u32
);
2125 void sctp_assoc_migrate(struct sctp_association
*, struct sock
*);
2126 int sctp_assoc_update(struct sctp_association
*old
,
2127 struct sctp_association
*new);
2129 __u32
sctp_association_get_next_tsn(struct sctp_association
*);
2131 void sctp_assoc_update_frag_point(struct sctp_association
*asoc
);
2132 void sctp_assoc_set_pmtu(struct sctp_association
*asoc
, __u32 pmtu
);
2133 void sctp_assoc_sync_pmtu(struct sctp_association
*asoc
);
2134 void sctp_assoc_rwnd_increase(struct sctp_association
*, unsigned int);
2135 void sctp_assoc_rwnd_decrease(struct sctp_association
*, unsigned int);
2136 void sctp_assoc_set_primary(struct sctp_association
*,
2137 struct sctp_transport
*);
2138 void sctp_assoc_del_nonprimary_peers(struct sctp_association
*,
2139 struct sctp_transport
*);
2140 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association
*asoc
,
2141 enum sctp_scope scope
, gfp_t gfp
);
2142 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association
*,
2143 struct sctp_cookie
*,
2145 int sctp_assoc_set_id(struct sctp_association
*, gfp_t
);
2146 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association
*asoc
);
2147 struct sctp_chunk
*sctp_assoc_lookup_asconf_ack(
2148 const struct sctp_association
*asoc
,
2150 void sctp_asconf_queue_teardown(struct sctp_association
*asoc
);
2152 int sctp_cmp_addr_exact(const union sctp_addr
*ss1
,
2153 const union sctp_addr
*ss2
);
2154 struct sctp_chunk
*sctp_get_ecne_prepend(struct sctp_association
*asoc
);
2156 /* A convenience structure to parse out SCTP specific CMSGs. */
2158 struct sctp_initmsg
*init
;
2159 struct sctp_sndrcvinfo
*srinfo
;
2160 struct sctp_sndinfo
*sinfo
;
2161 struct sctp_prinfo
*prinfo
;
2162 struct sctp_authinfo
*authinfo
;
2163 struct msghdr
*addrs_msg
;
2166 /* Structure for tracking memory objects */
2167 struct sctp_dbg_objcnt_entry
{
2172 #endif /* __sctp_structs_h__ */