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;
88 #include <net/sctp/tsnmap.h>
89 #include <net/sctp/ulpevent.h>
90 #include <net/sctp/ulpqueue.h>
92 /* Structures useful for managing bind/connect. */
94 struct sctp_bind_bucket {
96 unsigned short fastreuse;
97 struct hlist_node node;
98 struct hlist_head owner;
102 struct sctp_bind_hashbucket {
104 struct hlist_head chain;
107 /* Used for hashing all associations. */
108 struct sctp_hashbucket {
110 struct hlist_head chain;
111 } __attribute__((__aligned__(8)));
114 /* The SCTP globals structure. */
115 extern struct sctp_globals {
116 /* This is a list of groups of functions for each address
117 * family that we support.
119 struct list_head address_families;
121 /* This is the hash of all endpoints. */
122 struct sctp_hashbucket *ep_hashtable;
123 /* This is the sctp port control hash. */
124 struct sctp_bind_hashbucket *port_hashtable;
125 /* This is the hash of all transports. */
126 struct rhltable transport_hashtable;
128 /* Sizes of above hashtables. */
132 /* Default initialization values to be applied to new associations. */
134 __u16 max_outstreams;
136 /* Flag to indicate whether computing and verifying checksum
138 bool checksum_disable;
141 #define sctp_max_instreams (sctp_globals.max_instreams)
142 #define sctp_max_outstreams (sctp_globals.max_outstreams)
143 #define sctp_address_families (sctp_globals.address_families)
144 #define sctp_ep_hashsize (sctp_globals.ep_hashsize)
145 #define sctp_ep_hashtable (sctp_globals.ep_hashtable)
146 #define sctp_port_hashsize (sctp_globals.port_hashsize)
147 #define sctp_port_hashtable (sctp_globals.port_hashtable)
148 #define sctp_transport_hashtable (sctp_globals.transport_hashtable)
149 #define sctp_checksum_disable (sctp_globals.checksum_disable)
151 /* SCTP Socket type: UDP or TCP style. */
154 SCTP_SOCKET_UDP_HIGH_BANDWIDTH,
156 } sctp_socket_type_t;
158 /* Per socket SCTP information. */
160 /* inet_sock has to be the first member of sctp_sock */
161 struct inet_sock inet;
162 /* What kind of a socket is this? */
163 sctp_socket_type_t type;
165 /* PF_ family specific functions. */
168 /* Access to HMAC transform. */
169 struct crypto_shash *hmac;
172 /* What is our base endpointer? */
173 struct sctp_endpoint *ep;
175 struct sctp_bind_bucket *bind_hash;
176 /* Various Socket Options. */
177 __u16 default_stream;
180 __u32 default_context;
181 __u32 default_timetolive;
182 __u32 default_rcv_context;
185 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
186 * the destination address every heartbeat interval. This value
187 * will be inherited by all new associations.
191 /* This is the max_retrans value for new associations. */
194 /* The initial Path MTU to use for new associations. */
197 /* The default SACK delay timeout for new associations. */
201 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
204 struct sctp_initmsg initmsg;
205 struct sctp_rtoinfo rtoinfo;
206 struct sctp_paddrparams paddrparam;
207 struct sctp_event_subscribe subscribe;
208 struct sctp_assocparams assocparams;
213 __u32 adaptation_ind;
221 data_ready_signalled:1;
224 /* Receive to here while partial delivery is in effect. */
225 struct sk_buff_head pd_lobby;
227 /* These must be the last fields, as they will skipped on copies,
228 * like on accept and peeloff operations
230 struct list_head auto_asconf_list;
234 static inline struct sctp_sock *sctp_sk(const struct sock *sk)
236 return (struct sctp_sock *)sk;
239 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
241 return (struct sock *)sp;
244 #if IS_ENABLED(CONFIG_IPV6)
246 struct sctp_sock sctp;
247 struct ipv6_pinfo inet6;
249 #endif /* CONFIG_IPV6 */
252 /* This is our APPLICATION-SPECIFIC state cookie.
253 * THIS IS NOT DICTATED BY THE SPECIFICATION.
255 /* These are the parts of an association which we send in the cookie.
256 * Most of these are straight out of:
257 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
263 /* My : Tag expected in every inbound packet and sent
264 * Verification: in the INIT or INIT ACK chunk.
269 /* Peer's : Tag expected in every outbound packet except
270 * Verification: in the INIT chunk.
275 /* The rest of these are not from the spec, but really need to
279 /* My Tie Tag : Assist in discovering a restarting association. */
282 /* Peer's Tie Tag: Assist in discovering a restarting association. */
285 /* When does this cookie expire? */
288 /* Number of inbound/outbound streams which are set
289 * and negotiated during the INIT process.
291 __u16 sinit_num_ostreams;
292 __u16 sinit_max_instreams;
294 /* This is the first sequence number I used. */
297 /* This holds the originating address of the INIT packet. */
298 union sctp_addr peer_addr;
301 * Include the source port of the INIT-ACK
307 /* Padding for future use */
310 __u32 adaptation_ind;
312 __u8 auth_random[sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH];
313 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2];
314 __u8 auth_chunks[sizeof(sctp_paramhdr_t) + SCTP_AUTH_MAX_CHUNKS];
316 /* This is a shim for my peer's INIT packet, followed by
317 * a copy of the raw address list of the association.
318 * The length of the raw address list is saved in the
319 * raw_addr_list_len field, which will be used at the time when
320 * the association TCB is re-constructed from the cookie.
322 __u32 raw_addr_list_len;
323 struct sctp_init_chunk peer_init[0];
327 /* The format of our cookie that we send to our peer. */
328 struct sctp_signed_cookie {
329 __u8 signature[SCTP_SECRET_SIZE];
330 __u32 __pad; /* force sctp_cookie alignment to 64 bits */
331 struct sctp_cookie c;
334 /* This is another convenience type to allocate memory for address
335 * params for the maximum size and pass such structures around
338 union sctp_addr_param {
339 struct sctp_paramhdr p;
340 struct sctp_ipv4addr_param v4;
341 struct sctp_ipv6addr_param v6;
344 /* A convenience type to allow walking through the various
345 * parameters and avoid casting all over the place.
349 struct sctp_paramhdr *p;
350 struct sctp_cookie_preserve_param *life;
351 struct sctp_hostname_param *dns;
352 struct sctp_cookie_param *cookie;
353 struct sctp_supported_addrs_param *sat;
354 struct sctp_ipv4addr_param *v4;
355 struct sctp_ipv6addr_param *v6;
356 union sctp_addr_param *addr;
357 struct sctp_adaptation_ind_param *aind;
358 struct sctp_supported_ext_param *ext;
359 struct sctp_random_param *random;
360 struct sctp_chunks_param *chunks;
361 struct sctp_hmac_algo_param *hmac_algo;
362 struct sctp_addip_param *addip;
365 /* RFC 2960. Section 3.3.5 Heartbeat.
366 * Heartbeat Information: variable length
367 * The Sender-specific Heartbeat Info field should normally include
368 * information about the sender's current time when this HEARTBEAT
369 * chunk is sent and the destination transport address to which this
370 * HEARTBEAT is sent (see Section 8.3).
372 typedef struct sctp_sender_hb_info {
373 struct sctp_paramhdr param_hdr;
374 union sctp_addr daddr;
375 unsigned long sent_at;
377 } __packed sctp_sender_hb_info_t;
379 struct sctp_stream *sctp_stream_new(__u16 incnt, __u16 outcnt, gfp_t gfp);
380 void sctp_stream_free(struct sctp_stream *stream);
381 void sctp_stream_clear(struct sctp_stream *stream);
383 /* What is the current SSN number for this stream? */
384 #define sctp_ssn_peek(stream, type, sid) \
385 ((stream)->type[sid].ssn)
387 /* Return the next SSN number for this stream. */
388 #define sctp_ssn_next(stream, type, sid) \
389 ((stream)->type[sid].ssn++)
391 /* Skip over this ssn and all below. */
392 #define sctp_ssn_skip(stream, type, sid, ssn) \
393 ((stream)->type[sid].ssn = ssn + 1)
396 * Pointers to address related SCTP functions.
397 * (i.e. things that depend on the address family.)
400 int (*sctp_xmit) (struct sk_buff *skb,
401 struct sctp_transport *);
402 int (*setsockopt) (struct sock *sk,
406 unsigned int optlen);
407 int (*getsockopt) (struct sock *sk,
412 int (*compat_setsockopt) (struct sock *sk,
416 unsigned int optlen);
417 int (*compat_getsockopt) (struct sock *sk,
422 void (*get_dst) (struct sctp_transport *t,
423 union sctp_addr *saddr,
426 void (*get_saddr) (struct sctp_sock *sk,
427 struct sctp_transport *t,
429 void (*copy_addrlist) (struct list_head *,
430 struct net_device *);
431 int (*cmp_addr) (const union sctp_addr *addr1,
432 const union sctp_addr *addr2);
433 void (*addr_copy) (union sctp_addr *dst,
434 union sctp_addr *src);
435 void (*from_skb) (union sctp_addr *,
438 void (*from_sk) (union sctp_addr *,
440 void (*from_addr_param) (union sctp_addr *,
441 union sctp_addr_param *,
442 __be16 port, int iif);
443 int (*to_addr_param) (const union sctp_addr *,
444 union sctp_addr_param *);
445 int (*addr_valid) (union sctp_addr *,
447 const struct sk_buff *);
448 sctp_scope_t (*scope) (union sctp_addr *);
449 void (*inaddr_any) (union sctp_addr *, __be16);
450 int (*is_any) (const union sctp_addr *);
451 int (*available) (union sctp_addr *,
453 int (*skb_iif) (const struct sk_buff *sk);
454 int (*is_ce) (const struct sk_buff *sk);
455 void (*seq_dump_addr)(struct seq_file *seq,
456 union sctp_addr *addr);
457 void (*ecn_capable)(struct sock *sk);
458 __u16 net_header_len;
460 sa_family_t sa_family;
461 struct list_head list;
464 struct sctp_af *sctp_get_af_specific(sa_family_t);
465 int sctp_register_af(struct sctp_af *);
467 /* Protocol family functions. */
469 void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
470 void (*skb_msgname) (struct sk_buff *, char *, int *);
471 int (*af_supported) (sa_family_t, struct sctp_sock *);
472 int (*cmp_addr) (const union sctp_addr *,
473 const union sctp_addr *,
475 int (*bind_verify) (struct sctp_sock *, union sctp_addr *);
476 int (*send_verify) (struct sctp_sock *, union sctp_addr *);
477 int (*supported_addrs)(const struct sctp_sock *, __be16 *);
478 struct sock *(*create_accept_sk) (struct sock *sk,
479 struct sctp_association *asoc);
480 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr);
481 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk);
482 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk);
487 /* Structure to track chunk fragments that have been acked, but peer
488 * fragments of the same message have not.
490 struct sctp_datamsg {
491 /* Chunks waiting to be submitted to lower layer. */
492 struct list_head chunks;
493 /* Reference counting. */
495 /* When is this message no longer interesting to the peer? */
496 unsigned long expires_at;
497 /* Did the messenge fail to send? */
500 can_delay; /* should this message be Nagle delayed */
503 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
504 struct sctp_sndrcvinfo *,
506 void sctp_datamsg_free(struct sctp_datamsg *);
507 void sctp_datamsg_put(struct sctp_datamsg *);
508 void sctp_chunk_fail(struct sctp_chunk *, int error);
509 int sctp_chunk_abandoned(struct sctp_chunk *);
511 /* RFC2960 1.4 Key Terms
513 * o Chunk: A unit of information within an SCTP packet, consisting of
514 * a chunk header and chunk-specific content.
516 * As a matter of convenience, we remember the SCTP common header for
517 * each chunk as well as a few other header pointers...
520 struct list_head list;
524 /* How many times this chunk have been sent, for prsctp RTX policy */
527 /* This is our link to the per-transport transmitted list. */
528 struct list_head transmitted_list;
530 /* This field is used by chunks that hold fragmented data.
531 * For the first fragment this is the list that holds the rest of
532 * fragments. For the remaining fragments, this is the link to the
533 * frag_list maintained in the first fragment.
535 struct list_head frag_list;
537 /* This points to the sk_buff containing the actual data. */
540 /* In case of GSO packets, this will store the head one */
541 struct sk_buff *head_skb;
543 /* These are the SCTP headers by reverse order in a packet.
544 * Note that some of these may happen more than once. In that
545 * case, we point at the "current" one, whatever that means
546 * for that level of header.
549 /* We point this at the FIRST TLV parameter to chunk_hdr. */
550 union sctp_params param_hdr;
553 struct sctp_datahdr *data_hdr;
554 struct sctp_inithdr *init_hdr;
555 struct sctp_sackhdr *sack_hdr;
556 struct sctp_heartbeathdr *hb_hdr;
557 struct sctp_sender_hb_info *hbs_hdr;
558 struct sctp_shutdownhdr *shutdown_hdr;
559 struct sctp_signed_cookie *cookie_hdr;
560 struct sctp_ecnehdr *ecne_hdr;
561 struct sctp_cwrhdr *ecn_cwr_hdr;
562 struct sctp_errhdr *err_hdr;
563 struct sctp_addiphdr *addip_hdr;
564 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
565 struct sctp_authhdr *auth_hdr;
570 struct sctp_chunkhdr *chunk_hdr;
571 struct sctphdr *sctp_hdr;
573 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
574 struct sctp_sndrcvinfo sinfo;
576 /* Which association does this belong to? */
577 struct sctp_association *asoc;
579 /* What endpoint received this chunk? */
580 struct sctp_ep_common *rcvr;
582 /* We fill this in if we are calculating RTT. */
583 unsigned long sent_at;
585 /* What is the origin IP address for this chunk? */
586 union sctp_addr source;
587 /* Destination address for this chunk. */
588 union sctp_addr dest;
590 /* For outbound message, track all fragments for SEND_FAILED. */
591 struct sctp_datamsg *msg;
593 /* For an inbound chunk, this tells us where it came from.
594 * For an outbound chunk, it tells us where we'd like it to
595 * go. It is NULL if we have no preference.
597 struct sctp_transport *transport;
599 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO
600 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
601 * spec violates the principle premis that all chunks are processed
604 struct sk_buff *auth_chunk;
606 #define SCTP_CAN_FRTX 0x0
607 #define SCTP_NEED_FRTX 0x1
608 #define SCTP_DONT_FRTX 0x2
609 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */
610 has_tsn:1, /* Does this chunk have a TSN yet? */
611 has_ssn:1, /* Does this chunk have a SSN yet? */
612 singleton:1, /* Only chunk in the packet? */
613 end_of_packet:1, /* Last chunk in the packet? */
614 ecn_ce_done:1, /* Have we processed the ECN CE bit? */
615 pdiscard:1, /* Discard the whole packet now? */
616 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */
617 data_accepted:1, /* At least 1 chunk accepted */
618 auth:1, /* IN: was auth'ed | OUT: needs auth */
619 has_asconf:1, /* IN: have seen an asconf before */
620 tsn_missing_report:2, /* Data chunk missing counter. */
621 fast_retransmit:2; /* Is this chunk fast retransmitted? */
624 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1)
625 void sctp_chunk_hold(struct sctp_chunk *);
626 void sctp_chunk_put(struct sctp_chunk *);
627 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len,
628 struct iov_iter *from);
629 void sctp_chunk_free(struct sctp_chunk *);
630 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
631 struct sctp_chunk *sctp_chunkify(struct sk_buff *,
632 const struct sctp_association *,
633 struct sock *, gfp_t gfp);
634 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
636 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
639 SCTP_ADDR_NEW, /* new address added to assoc/ep */
640 SCTP_ADDR_SRC, /* address can be used as source */
641 SCTP_ADDR_DEL, /* address about to be deleted */
644 /* This is a structure for holding either an IPv6 or an IPv4 address. */
645 struct sctp_sockaddr_entry {
646 struct list_head list;
653 #define SCTP_ADDRESS_TICK_DELAY 500
655 typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *);
657 /* This structure holds lists of chunks as we are assembling for
661 /* These are the SCTP header values (host order) for the packet. */
663 __u16 destination_port;
666 /* This contains the payload chunks. */
667 struct list_head chunk_list;
669 /* This is the overhead of the sctp and ip headers. */
671 /* This is the total size of all chunks INCLUDING padding. */
673 /* This is the maximum size this packet may have */
676 /* The packet is destined for this transport address.
677 * The function we finally use to pass down to the next lower
678 * layer lives in the transport structure.
680 struct sctp_transport *transport;
682 /* pointer to the auth chunk for this packet */
683 struct sctp_chunk *auth;
685 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */
686 has_sack:1, /* This packet contains a SACK chunk. */
687 has_auth:1, /* This packet contains an AUTH chunk */
688 has_data:1, /* This packet contains at least 1 DATA chunk */
689 ipfragok:1; /* So let ip fragment this packet */
692 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *,
693 __u16 sport, __u16 dport);
694 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
695 sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *,
696 struct sctp_chunk *, int, gfp_t);
697 sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *,
698 struct sctp_chunk *);
699 int sctp_packet_transmit(struct sctp_packet *, gfp_t);
700 void sctp_packet_free(struct sctp_packet *);
702 static inline int sctp_packet_empty(struct sctp_packet *packet)
704 return packet->size == packet->overhead;
707 /* This represents a remote transport address.
708 * For local transport addresses, we just use union sctp_addr.
710 * RFC2960 Section 1.4 Key Terms
712 * o Transport address: A Transport Address is traditionally defined
713 * by Network Layer address, Transport Layer protocol and Transport
714 * Layer port number. In the case of SCTP running over IP, a
715 * transport address is defined by the combination of an IP address
716 * and an SCTP port number (where SCTP is the Transport protocol).
718 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
720 * o The sender keeps a separate congestion control parameter set for
721 * each of the destination addresses it can send to (not each
722 * source-destination pair but for each destination). The parameters
723 * should decay if the address is not used for a long enough time
727 struct sctp_transport {
728 /* A list of transports. */
729 struct list_head transports;
730 struct rhlist_head node;
732 /* Reference counting. */
734 /* RTO-Pending : A flag used to track if one of the DATA
735 * chunks sent to this address is currently being
736 * used to compute a RTT. If this flag is 0,
737 * the next DATA chunk sent to this destination
738 * should be used to compute a RTT and this flag
739 * should be set. Every time the RTT
740 * calculation completes (i.e. the DATA chunk
741 * is SACK'd) clear this flag.
746 * hb_sent : a flag that signals that we have a pending
751 /* Is the Path MTU update pending on this tranport */
754 /* Has this transport moved the ctsn since we last sacked */
760 /* This is the peer's IP address and port. */
761 union sctp_addr ipaddr;
763 /* These are the functions we call to handle LLP stuff. */
764 struct sctp_af *af_specific;
766 /* Which association do we belong to? */
767 struct sctp_association *asoc;
771 * 12.3 Per Transport Address Data
773 * For each destination transport address in the peer's
774 * address list derived from the INIT or INIT ACK chunk, a
775 * number of data elements needs to be maintained including:
777 /* RTO : The current retransmission timeout value. */
780 __u32 rtt; /* This is the most recent RTT. */
782 /* RTTVAR : The current RTT variation. */
785 /* SRTT : The current smoothed round trip time. */
789 * These are the congestion stats.
791 /* cwnd : The current congestion window. */
792 __u32 cwnd; /* This is the actual cwnd. */
794 /* ssthresh : The current slow start threshold value. */
797 /* partial : The tracking method for increase of cwnd when in
798 * bytes acked : congestion avoidance mode (see Section 6.2.2)
800 __u32 partial_bytes_acked;
802 /* Data that has been sent, but not acknowledged. */
805 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */
808 struct dst_entry *dst;
809 /* Source address. */
810 union sctp_addr saddr;
812 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
813 * the destination address every heartbeat interval.
815 unsigned long hbinterval;
817 /* SACK delay timeout */
818 unsigned long sackdelay;
821 /* When was the last time that we heard from this transport? We use
822 * this to pick new active and retran paths.
824 ktime_t last_time_heard;
826 /* When was the last time that we sent a chunk using this
827 * transport? We use this to check for idle transports
829 unsigned long last_time_sent;
831 /* Last time(in jiffies) when cwnd is reduced due to the congestion
832 * indication based on ECNE chunk.
834 unsigned long last_time_ecne_reduced;
836 /* This is the max_retrans value for the transport and will
837 * be initialized from the assocs value. This can be changed
838 * using the SCTP_SET_PEER_ADDR_PARAMS socket option.
842 /* This is the partially failed retrans value for the transport
843 * and will be initialized from the assocs value. This can be changed
844 * using the SCTP_PEER_ADDR_THLDS socket option
847 /* PMTU : The current known path MTU. */
850 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
853 /* The number of times INIT has been sent on this transport. */
856 /* state : The current state of this destination,
857 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
861 /* These are the error stats for this destination. */
863 /* Error count : The current error count for this destination. */
864 unsigned short error_count;
866 /* Per : A timer used by each destination.
870 * [Everywhere else in the text this is called T3-rtx. -ed]
872 struct timer_list T3_rtx_timer;
874 /* Heartbeat timer is per destination. */
875 struct timer_list hb_timer;
877 /* Timer to handle ICMP proto unreachable envets */
878 struct timer_list proto_unreach_timer;
880 /* Timer to handler reconf chunk rtx */
881 struct timer_list reconf_timer;
883 /* Since we're using per-destination retransmission timers
884 * (see above), we're also using per-destination "transmitted"
885 * queues. This probably ought to be a private struct
886 * accessible only within the outqueue, but it's not, yet.
888 struct list_head transmitted;
890 /* We build bundle-able packets for this transport here. */
891 struct sctp_packet packet;
893 /* This is the list of transports that have chunks to send. */
894 struct list_head send_ready;
896 /* State information saved for SFR_CACC algorithm. The key
897 * idea in SFR_CACC is to maintain state at the sender on a
898 * per-destination basis when a changeover happens.
899 * char changeover_active;
900 * char cycling_changeover;
901 * __u32 next_tsn_at_change;
902 * char cacc_saw_newack;
905 /* An unsigned integer, which stores the next TSN to be
906 * used by the sender, at the moment of changeover.
908 __u32 next_tsn_at_change;
910 /* A flag which indicates the occurrence of a changeover */
911 char changeover_active;
913 /* A flag which indicates whether the change of primary is
914 * the first switch to this destination address during an
917 char cycling_changeover;
919 /* A temporary flag, which is used during the processing of
920 * a SACK to estimate the causative TSN(s)'s group.
922 char cacc_saw_newack;
925 /* 64-bit random number sent with heartbeat. */
931 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *,
933 void sctp_transport_set_owner(struct sctp_transport *,
934 struct sctp_association *);
935 void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
937 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk);
938 void sctp_transport_free(struct sctp_transport *);
939 void sctp_transport_reset_t3_rtx(struct sctp_transport *);
940 void sctp_transport_reset_hb_timer(struct sctp_transport *);
941 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport);
942 int sctp_transport_hold(struct sctp_transport *);
943 void sctp_transport_put(struct sctp_transport *);
944 void sctp_transport_update_rto(struct sctp_transport *, __u32);
945 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
946 void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t);
947 void sctp_transport_burst_limited(struct sctp_transport *);
948 void sctp_transport_burst_reset(struct sctp_transport *);
949 unsigned long sctp_transport_timeout(struct sctp_transport *);
950 void sctp_transport_reset(struct sctp_transport *);
951 void sctp_transport_update_pmtu(struct sock *, struct sctp_transport *, u32);
952 void sctp_transport_immediate_rtx(struct sctp_transport *);
955 /* This is the structure we use to queue packets as they come into
956 * SCTP. We write packets to it and read chunks from it.
959 /* This is actually a queue of sctp_chunk each
960 * containing a partially decoded packet.
962 struct list_head in_chunk_list;
963 /* This is the packet which is currently off the in queue and is
964 * being worked on through the inbound chunk processing.
966 struct sctp_chunk *in_progress;
968 /* This is the delayed task to finish delivering inbound
971 struct work_struct immediate;
974 void sctp_inq_init(struct sctp_inq *);
975 void sctp_inq_free(struct sctp_inq *);
976 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
977 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
978 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *);
979 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t);
981 /* This is the structure we use to hold outbound chunks. You push
982 * chunks in and they automatically pop out the other end as bundled
983 * packets (it calls (*output_handler)()).
985 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
986 * and 8.2 of the v13 draft.
988 * It handles retransmissions. The connection to the timeout portion
989 * of the state machine is through sctp_..._timeout() and timeout_handler.
991 * If you feed it SACKs, it will eat them.
993 * If you give it big chunks, it will fragment them.
995 * It assigns TSN's to data chunks. This happens at the last possible
996 * instant before transmission.
998 * When free()'d, it empties itself out via output_handler().
1001 struct sctp_association *asoc;
1003 /* Data pending that has never been transmitted. */
1004 struct list_head out_chunk_list;
1006 unsigned int out_qlen; /* Total length of queued data chunks. */
1008 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1011 /* These are control chunks we want to send. */
1012 struct list_head control_chunk_list;
1014 /* These are chunks that have been sacked but are above the
1015 * CTSN, or cumulative tsn ack point.
1017 struct list_head sacked;
1019 /* Put chunks on this list to schedule them for
1022 struct list_head retransmit;
1024 /* Put chunks on this list to save them for FWD TSN processing as
1025 * they were abandoned.
1027 struct list_head abandoned;
1029 /* How many unackd bytes do we have in-flight? */
1030 __u32 outstanding_bytes;
1032 /* Are we doing fast-rtx on this queue */
1039 void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1040 void sctp_outq_teardown(struct sctp_outq *);
1041 void sctp_outq_free(struct sctp_outq*);
1042 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t);
1043 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *);
1044 int sctp_outq_is_empty(const struct sctp_outq *);
1045 void sctp_outq_restart(struct sctp_outq *);
1047 void sctp_retransmit(struct sctp_outq *, struct sctp_transport *,
1048 sctp_retransmit_reason_t);
1049 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1050 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp);
1051 void sctp_prsctp_prune(struct sctp_association *asoc,
1052 struct sctp_sndrcvinfo *sinfo, int msg_len);
1053 /* Uncork and flush an outqueue. */
1054 static inline void sctp_outq_cork(struct sctp_outq *q)
1059 /* SCTP skb control block.
1060 * sctp_input_cb is currently used on rx and sock rx queue
1062 struct sctp_input_cb {
1064 struct inet_skb_parm h4;
1065 #if IS_ENABLED(CONFIG_IPV6)
1066 struct inet6_skb_parm h6;
1069 struct sctp_chunk *chunk;
1072 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0]))
1074 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb)
1076 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk;
1078 return chunk->head_skb ? : skb;
1081 /* These bind address data fields common between endpoints and associations */
1082 struct sctp_bind_addr {
1084 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1086 * SCTP Port: The local SCTP port number the endpoint is
1091 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1093 * Address List: The list of IP addresses that this instance
1094 * has bound. This information is passed to one's
1095 * peer(s) in INIT and INIT ACK chunks.
1097 struct list_head address_list;
1100 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1101 void sctp_bind_addr_free(struct sctp_bind_addr *);
1102 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest,
1103 const struct sctp_bind_addr *src,
1104 sctp_scope_t scope, gfp_t gfp,
1106 int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
1107 const struct sctp_bind_addr *src,
1109 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1110 int new_size, __u8 addr_state, gfp_t gfp);
1111 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1112 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1113 struct sctp_sock *);
1114 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *,
1115 struct sctp_sock *, struct sctp_sock *);
1116 int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
1117 const union sctp_addr *addr);
1118 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp,
1119 const union sctp_addr *addrs,
1121 struct sctp_sock *opt);
1122 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1125 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1126 __u16 port, gfp_t gfp);
1128 sctp_scope_t sctp_scope(const union sctp_addr *);
1129 int sctp_in_scope(struct net *net, const union sctp_addr *addr, const sctp_scope_t scope);
1130 int sctp_is_any(struct sock *sk, const union sctp_addr *addr);
1131 int sctp_is_ep_boundall(struct sock *sk);
1134 /* What type of endpoint? */
1136 SCTP_EP_TYPE_SOCKET,
1137 SCTP_EP_TYPE_ASSOCIATION,
1138 } sctp_endpoint_type_t;
1141 * A common base class to bridge the implmentation view of a
1142 * socket (usually listening) endpoint versus an association's
1144 * This common structure is useful for several purposes:
1145 * 1) Common interface for lookup routines.
1146 * a) Subfunctions work for either endpoint or association
1147 * b) Single interface to lookup allows hiding the lookup lock rather
1148 * than acquiring it externally.
1149 * 2) Common interface for the inbound chunk handling/state machine.
1150 * 3) Common object handling routines for reference counting, etc.
1151 * 4) Disentangle association lookup from endpoint lookup, where we
1152 * do not have to find our endpoint to find our association.
1156 struct sctp_ep_common {
1157 /* Fields to help us manage our entries in the hash tables. */
1158 struct hlist_node node;
1161 /* Runtime type information. What kind of endpoint is this? */
1162 sctp_endpoint_type_t type;
1164 /* Some fields to help us manage this object.
1165 * refcnt - Reference count access to this object.
1166 * dead - Do not attempt to use this object.
1171 /* What socket does this endpoint belong to? */
1174 /* This is where we receive inbound chunks. */
1175 struct sctp_inq inqueue;
1177 /* This substructure includes the defining parameters of the
1179 * bind_addr.port is our shared port number.
1180 * bind_addr.address_list is our set of local IP addresses.
1182 struct sctp_bind_addr bind_addr;
1186 /* RFC Section 1.4 Key Terms
1188 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1189 * multi-homed host, an SCTP endpoint is represented to its peers as a
1190 * combination of a set of eligible destination transport addresses to
1191 * which SCTP packets can be sent and a set of eligible source
1192 * transport addresses from which SCTP packets can be received.
1193 * All transport addresses used by an SCTP endpoint must use the
1194 * same port number, but can use multiple IP addresses. A transport
1195 * address used by an SCTP endpoint must not be used by another
1196 * SCTP endpoint. In other words, a transport address is unique
1197 * to an SCTP endpoint.
1199 * From an implementation perspective, each socket has one of these.
1200 * A TCP-style socket will have exactly one association on one of
1201 * these. An UDP-style socket will have multiple associations hanging
1205 struct sctp_endpoint {
1206 /* Common substructure for endpoint and association. */
1207 struct sctp_ep_common base;
1209 /* Associations: A list of current associations and mappings
1210 * to the data consumers for each association. This
1211 * may be in the form of a hash table or other
1212 * implementation dependent structure. The data
1213 * consumers may be process identification
1214 * information such as file descriptors, named pipe
1215 * pointer, or table pointers dependent on how SCTP
1218 /* This is really a list of struct sctp_association entries. */
1219 struct list_head asocs;
1221 /* Secret Key: A secret key used by this endpoint to compute
1222 * the MAC. This SHOULD be a cryptographic quality
1223 * random number with a sufficient length.
1224 * Discussion in [RFC1750] can be helpful in
1225 * selection of the key.
1227 __u8 secret_key[SCTP_SECRET_SIZE];
1229 /* digest: This is a digest of the sctp cookie. This field is
1230 * only used on the receive path when we try to validate
1231 * that the cookie has not been tampered with. We put
1232 * this here so we pre-allocate this once and can re-use
1237 /* sendbuf acct. policy. */
1238 __u32 sndbuf_policy;
1240 /* rcvbuf acct. policy. */
1241 __u32 rcvbuf_policy;
1243 /* SCTP AUTH: array of the HMACs that will be allocated
1244 * we need this per association so that we don't serialize
1246 struct crypto_shash **auth_hmacs;
1248 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1249 struct sctp_hmac_algo_param *auth_hmacs_list;
1251 /* SCTP-AUTH: chunks to authenticate encoded into parameter */
1252 struct sctp_chunks_param *auth_chunk_list;
1254 /* SCTP-AUTH: endpoint shared keys */
1255 struct list_head endpoint_shared_keys;
1256 __u16 active_key_id;
1262 /* Recover the outter endpoint structure. */
1263 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1265 struct sctp_endpoint *ep;
1267 ep = container_of(base, struct sctp_endpoint, base);
1271 /* These are function signatures for manipulating endpoints. */
1272 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1273 void sctp_endpoint_free(struct sctp_endpoint *);
1274 void sctp_endpoint_put(struct sctp_endpoint *);
1275 void sctp_endpoint_hold(struct sctp_endpoint *);
1276 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1277 struct sctp_association *sctp_endpoint_lookup_assoc(
1278 const struct sctp_endpoint *ep,
1279 const union sctp_addr *paddr,
1280 struct sctp_transport **);
1281 int sctp_endpoint_is_peeled_off(struct sctp_endpoint *,
1282 const union sctp_addr *);
1283 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1284 struct net *, const union sctp_addr *);
1285 int sctp_has_association(struct net *net, const union sctp_addr *laddr,
1286 const union sctp_addr *paddr);
1288 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep,
1289 const struct sctp_association *asoc,
1290 sctp_cid_t, sctp_init_chunk_t *peer_init,
1291 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk);
1292 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk,
1293 const union sctp_addr *peer,
1294 sctp_init_chunk_t *init, gfp_t gfp);
1295 __u32 sctp_generate_tag(const struct sctp_endpoint *);
1296 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
1298 struct sctp_inithdr_host {
1301 __u16 num_outbound_streams;
1302 __u16 num_inbound_streams;
1306 struct sctp_stream_out {
1311 struct sctp_stream_in {
1315 struct sctp_stream {
1316 struct sctp_stream_out *out;
1317 struct sctp_stream_in *in;
1322 #define SCTP_STREAM_CLOSED 0x00
1323 #define SCTP_STREAM_OPEN 0x01
1325 /* SCTP_GET_ASSOC_STATS counters */
1326 struct sctp_priv_assoc_stats {
1327 /* Maximum observed rto in the association during subsequent
1328 * observations. Value is set to 0 if no RTO measurement took place
1329 * The transport where the max_rto was observed is returned in
1332 struct sockaddr_storage obs_rto_ipaddr;
1334 /* Total In and Out SACKs received and sent */
1337 /* Total In and Out packets received and sent */
1340 /* Total retransmitted chunks */
1342 /* TSN received > next expected */
1344 /* Duplicate Chunks received */
1346 /* Gap Ack Blocks received */
1348 /* Unordered data chunks sent and received */
1351 /* Ordered data chunks sent and received */
1354 /* Control chunks sent and received */
1361 * 12. Recommended Transmission Control Block (TCB) Parameters
1363 * This section details a recommended set of parameters that should
1364 * be contained within the TCB for an implementation. This section is
1365 * for illustrative purposes and should not be deemed as requirements
1366 * on an implementation or as an exhaustive list of all parameters
1367 * inside an SCTP TCB. Each implementation may need its own additional
1368 * parameters for optimization.
1372 /* Here we have information about each individual association. */
1373 struct sctp_association {
1375 /* A base structure common to endpoint and association.
1376 * In this context, it represents the associations's view
1377 * of the local endpoint of the association.
1379 struct sctp_ep_common base;
1381 /* Associations on the same socket. */
1382 struct list_head asocs;
1384 /* association id. */
1385 sctp_assoc_t assoc_id;
1387 /* This is our parent endpoint. */
1388 struct sctp_endpoint *ep;
1390 /* These are those association elements needed in the cookie. */
1391 struct sctp_cookie c;
1393 /* This is all information about our peer. */
1395 /* transport_addr_list
1397 * Peer : A list of SCTP transport addresses that the
1398 * Transport : peer is bound to. This information is derived
1399 * Address : from the INIT or INIT ACK and is used to
1400 * List : associate an inbound packet with a given
1401 * : association. Normally this information is
1402 * : hashed or keyed for quick lookup and access
1404 * : The list is also initialized with the list
1405 * : of addresses passed with the sctp_connectx()
1408 * It is a list of SCTP_transport's.
1410 struct list_head transport_addr_list;
1414 * Peer Rwnd : Current calculated value of the peer's rwnd.
1420 * Peer : A count of the number of peer addresses
1421 * Transport : in the Peer Transport Address List.
1425 __u16 transport_count;
1428 * The transport layer port number.
1434 * Primary : This is the current primary destination
1435 * Path : transport address of the peer endpoint. It
1436 * : may also specify a source transport address
1437 * : on this endpoint.
1439 * All of these paths live on transport_addr_list.
1441 * At the bakeoffs, we discovered that the intent of
1442 * primaryPath is that it only changes when the ULP
1443 * asks to have it changed. We add the activePath to
1444 * designate the connection we are currently using to
1445 * transmit new data and most control chunks.
1447 struct sctp_transport *primary_path;
1449 /* Cache the primary path address here, when we
1450 * need a an address for msg_name.
1452 union sctp_addr primary_addr;
1455 * The path that we are currently using to
1456 * transmit new data and most control chunks.
1458 struct sctp_transport *active_path;
1462 * RFC2960 6.4 Multi-homed SCTP Endpoints
1464 * Furthermore, when its peer is multi-homed, an
1465 * endpoint SHOULD try to retransmit a chunk to an
1466 * active destination transport address that is
1467 * different from the last destination address to
1468 * which the DATA chunk was sent.
1470 struct sctp_transport *retran_path;
1472 /* Pointer to last transport I have sent on. */
1473 struct sctp_transport *last_sent_to;
1475 /* This is the last transport I have received DATA on. */
1476 struct sctp_transport *last_data_from;
1479 * Mapping An array of bits or bytes indicating which out of
1480 * Array order TSN's have been received (relative to the
1481 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1482 * order packets have been received, this array
1483 * will be set to all zero. This structure may be
1484 * in the form of a circular buffer or bit array.
1486 * Last Rcvd : This is the last TSN received in
1487 * TSN : sequence. This value is set initially by
1488 * : taking the peer's Initial TSN, received in
1489 * : the INIT or INIT ACK chunk, and subtracting
1492 * Throughout most of the specification this is called the
1493 * "Cumulative TSN ACK Point". In this case, we
1494 * ignore the advice in 12.2 in favour of the term
1495 * used in the bulk of the text. This value is hidden
1496 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1498 struct sctp_tsnmap tsn_map;
1500 /* This mask is used to disable sending the ASCONF chunk
1501 * with specified parameter to peer.
1503 __be16 addip_disabled_mask;
1505 /* These are capabilities which our peer advertised. */
1506 __u8 ecn_capable:1, /* Can peer do ECN? */
1507 ipv4_address:1, /* Peer understands IPv4 addresses? */
1508 ipv6_address:1, /* Peer understands IPv6 addresses? */
1509 hostname_address:1, /* Peer understands DNS addresses? */
1510 asconf_capable:1, /* Does peer support ADDIP? */
1511 prsctp_capable:1, /* Can peer do PR-SCTP? */
1512 reconf_capable:1, /* Can peer do RE-CONFIG? */
1513 auth_capable:1; /* Is peer doing SCTP-AUTH? */
1515 /* sack_needed : This flag indicates if the next received
1516 * : packet is to be responded to with a
1517 * : SACK. This is initialized to 0. When a packet
1518 * : is received sack_cnt is incremented. If this value
1519 * : reaches 2 or more, a SACK is sent and the
1520 * : value is reset to 0. Note: This is used only
1521 * : when no DATA chunks are received out of
1522 * : order. When DATA chunks are out of order,
1523 * : SACK's are not delayed (see Section 6).
1525 __u8 sack_needed:1, /* Do we need to sack the peer? */
1527 zero_window_announced:1;
1530 __u32 adaptation_ind; /* Adaptation Code point. */
1532 struct sctp_inithdr_host i;
1536 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1537 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1538 * Initial TSN Value minus 1
1542 /* SCTP-AUTH: We need to know pears random number, hmac list
1543 * and authenticated chunk list. All that is part of the
1544 * cookie and these are just pointers to those locations
1546 sctp_random_param_t *peer_random;
1547 sctp_chunks_param_t *peer_chunks;
1548 sctp_hmac_algo_param_t *peer_hmacs;
1551 /* State : A state variable indicating what state the
1552 * : association is in, i.e. COOKIE-WAIT,
1553 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1554 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1556 * Note: No "CLOSED" state is illustrated since if a
1557 * association is "CLOSED" its TCB SHOULD be removed.
1559 * In this implementation we DO have a CLOSED
1560 * state which is used during initiation and shutdown.
1562 * State takes values from SCTP_STATE_*.
1566 /* Overall : The overall association error count.
1567 * Error Count : [Clear this any time I get something.]
1569 int overall_error_count;
1571 /* The cookie life I award for any cookie. */
1572 ktime_t cookie_life;
1574 /* These are the association's initial, max, and min RTO values.
1575 * These values will be initialized by system defaults, but can
1576 * be modified via the SCTP_RTOINFO socket option.
1578 unsigned long rto_initial;
1579 unsigned long rto_max;
1580 unsigned long rto_min;
1582 /* Maximum number of new data packets that can be sent in a burst. */
1585 /* This is the max_retrans value for the association. This value will
1586 * be initialized initialized from system defaults, but can be
1587 * modified by the SCTP_ASSOCINFO socket option.
1591 /* This is the partially failed retrans value for the transport
1592 * and will be initialized from the assocs value. This can be
1593 * changed using the SCTP_PEER_ADDR_THLDS socket option
1597 /* Maximum number of times the endpoint will retransmit INIT */
1598 __u16 max_init_attempts;
1600 /* How many times have we resent an INIT? */
1603 /* The largest timeout or RTO value to use in attempting an INIT */
1604 unsigned long max_init_timeo;
1606 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1607 * the destination address every heartbeat interval. This value
1608 * will be inherited by all new transports.
1610 unsigned long hbinterval;
1612 /* This is the max_retrans value for new transports in the
1617 /* Flag that path mtu update is pending */
1620 /* Association : The smallest PMTU discovered for all of the
1621 * PMTU : peer's transport addresses.
1625 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1629 /* SACK delay timeout */
1630 unsigned long sackdelay;
1632 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES];
1633 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1635 /* Transport to which SHUTDOWN chunk was last sent. */
1636 struct sctp_transport *shutdown_last_sent_to;
1638 /* Transport to which INIT chunk was last sent. */
1639 struct sctp_transport *init_last_sent_to;
1641 /* How many times have we resent a SHUTDOWN */
1642 int shutdown_retries;
1644 /* Next TSN : The next TSN number to be assigned to a new
1645 * : DATA chunk. This is sent in the INIT or INIT
1646 * : ACK chunk to the peer and incremented each
1647 * : time a DATA chunk is assigned a TSN
1648 * : (normally just prior to transmit or during
1654 * Last Rcvd : This is the last TSN received in sequence. This value
1655 * TSN : is set initially by taking the peer's Initial TSN,
1656 * : received in the INIT or INIT ACK chunk, and
1657 * : subtracting one from it.
1659 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1662 __u32 ctsn_ack_point;
1664 /* PR-SCTP Advanced.Peer.Ack.Point */
1665 __u32 adv_peer_ack_point;
1667 /* Highest TSN that is acknowledged by incoming SACKs. */
1668 __u32 highest_sacked;
1670 /* TSN marking the fast recovery exit point */
1671 __u32 fast_recovery_exit;
1673 /* Flag to track the current fast recovery state */
1676 /* The number of unacknowledged data chunks. Reported through
1677 * the SCTP_STATUS sockopt.
1681 /* The total number of data chunks that we've had to retransmit
1682 * as the result of a T3 timer expiration
1684 __u32 rtx_data_chunks;
1686 /* This is the association's receive buffer space. This value is used
1687 * to set a_rwnd field in an INIT or a SACK chunk.
1691 /* This is the last advertised value of rwnd over a SACK chunk. */
1694 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1695 * to slop over a maximum of the association's frag_point.
1699 /* Keeps treack of rwnd pressure. This happens when we have
1700 * a window, but not recevie buffer (i.e small packets). This one
1701 * is releases slowly (1 PMTU at a time ).
1705 /* This is the sndbuf size in use for the association.
1706 * This corresponds to the sndbuf size for the association,
1707 * as specified in the sk->sndbuf.
1711 /* This is the amount of memory that this association has allocated
1712 * in the receive path at any given time.
1714 atomic_t rmem_alloc;
1716 /* This is the wait queue head for send requests waiting on
1717 * the association sndbuf space.
1719 wait_queue_head_t wait;
1721 /* The message size at which SCTP fragmentation will occur. */
1725 /* Counter used to count INIT errors. */
1726 int init_err_counter;
1728 /* Count the number of INIT cycles (for doubling timeout). */
1731 /* Default send parameters. */
1732 __u16 default_stream;
1733 __u16 default_flags;
1735 __u32 default_context;
1736 __u32 default_timetolive;
1738 /* Default receive parameters */
1739 __u32 default_rcv_context;
1742 struct sctp_stream *stream;
1744 /* All outbound chunks go through this structure. */
1745 struct sctp_outq outqueue;
1747 /* A smart pipe that will handle reordering and fragmentation,
1748 * as well as handle passing events up to the ULP.
1750 struct sctp_ulpq ulpq;
1752 /* Last TSN that caused an ECNE Chunk to be sent. */
1753 __u32 last_ecne_tsn;
1755 /* Last TSN that caused a CWR Chunk to be sent. */
1758 /* How many duplicated TSNs have we seen? */
1761 /* These are to support
1762 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1763 * and Enforcement of Flow and Message Limits"
1764 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1765 * or "ADDIP" for short.
1770 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1772 * R1) One and only one ASCONF Chunk MAY be in transit and
1773 * unacknowledged at any one time. If a sender, after sending
1774 * an ASCONF chunk, decides it needs to transfer another
1775 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1776 * returns from the previous ASCONF Chunk before sending a
1777 * subsequent ASCONF. Note this restriction binds each side,
1778 * so at any time two ASCONF may be in-transit on any given
1779 * association (one sent from each endpoint).
1781 * [This is our one-and-only-one ASCONF in flight. If we do
1782 * not have an ASCONF in flight, this is NULL.]
1784 struct sctp_chunk *addip_last_asconf;
1786 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
1788 * This is needed to implement itmes E1 - E4 of the updated
1789 * spec. Here is the justification:
1791 * Since the peer may bundle multiple ASCONF chunks toward us,
1792 * we now need the ability to cache multiple ACKs. The section
1793 * describes in detail how they are cached and cleaned up.
1795 struct list_head asconf_ack_list;
1797 /* These ASCONF chunks are waiting to be sent.
1799 * These chunaks can't be pushed to outqueue until receiving
1800 * ASCONF_ACK for the previous ASCONF indicated by
1801 * addip_last_asconf, so as to guarantee that only one ASCONF
1802 * is in flight at any time.
1804 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1806 * In defining the ASCONF Chunk transfer procedures, it is
1807 * essential that these transfers MUST NOT cause congestion
1808 * within the network. To achieve this, we place these
1809 * restrictions on the transfer of ASCONF Chunks:
1811 * R1) One and only one ASCONF Chunk MAY be in transit and
1812 * unacknowledged at any one time. If a sender, after sending
1813 * an ASCONF chunk, decides it needs to transfer another
1814 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1815 * returns from the previous ASCONF Chunk before sending a
1816 * subsequent ASCONF. Note this restriction binds each side,
1817 * so at any time two ASCONF may be in-transit on any given
1818 * association (one sent from each endpoint).
1821 * [I really think this is EXACTLY the sort of intelligence
1822 * which already resides in sctp_outq. Please move this
1823 * queue and its supporting logic down there. --piggy]
1825 struct list_head addip_chunk_list;
1827 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1829 * A2) A serial number should be assigned to the Chunk. The
1830 * serial number SHOULD be a monotonically increasing
1831 * number. The serial number SHOULD be initialized at
1832 * the start of the association to the same value as the
1833 * Initial TSN and every time a new ASCONF chunk is created
1834 * it is incremented by one after assigning the serial number
1835 * to the newly created chunk.
1838 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
1840 * Serial Number : 32 bits (unsigned integer)
1842 * This value represents a Serial Number for the ASCONF
1843 * Chunk. The valid range of Serial Number is from 0 to
1844 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
1845 * after reaching 4294967295.
1848 int src_out_of_asoc_ok;
1849 union sctp_addr *asconf_addr_del_pending;
1850 struct sctp_transport *new_transport;
1852 /* SCTP AUTH: list of the endpoint shared keys. These
1853 * keys are provided out of band by the user applicaton
1854 * and can't change during the lifetime of the association
1856 struct list_head endpoint_shared_keys;
1859 * The current generated assocaition shared key (secret)
1861 struct sctp_auth_bytes *asoc_shared_key;
1863 /* SCTP AUTH: hmac id of the first peer requested algorithm
1866 __u16 default_hmac_id;
1868 __u16 active_key_id;
1870 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */
1871 temp:1, /* Is it a temporary association? */
1875 __u32 strreset_outseq; /* Update after receiving response */
1876 __u32 strreset_inseq; /* Update after receiving request */
1878 struct sctp_chunk *strreset_chunk; /* save request chunk */
1880 struct sctp_priv_assoc_stats stats;
1882 int sent_cnt_removable;
1884 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1];
1885 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1];
1889 /* An eyecatcher for determining if we are really looking at an
1890 * association data structure.
1893 SCTP_ASSOC_EYECATCHER = 0xa550c123,
1896 /* Recover the outter association structure. */
1897 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
1899 struct sctp_association *asoc;
1901 asoc = container_of(base, struct sctp_association, base);
1905 /* These are function signatures for manipulating associations. */
1908 struct sctp_association *
1909 sctp_association_new(const struct sctp_endpoint *, const struct sock *,
1910 sctp_scope_t scope, gfp_t gfp);
1911 void sctp_association_free(struct sctp_association *);
1912 void sctp_association_put(struct sctp_association *);
1913 void sctp_association_hold(struct sctp_association *);
1915 struct sctp_transport *sctp_assoc_choose_alter_transport(
1916 struct sctp_association *, struct sctp_transport *);
1917 void sctp_assoc_update_retran_path(struct sctp_association *);
1918 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
1919 const union sctp_addr *);
1920 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1921 const union sctp_addr *laddr);
1922 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
1923 const union sctp_addr *address,
1925 const int peer_state);
1926 void sctp_assoc_del_peer(struct sctp_association *asoc,
1927 const union sctp_addr *addr);
1928 void sctp_assoc_rm_peer(struct sctp_association *asoc,
1929 struct sctp_transport *peer);
1930 void sctp_assoc_control_transport(struct sctp_association *,
1931 struct sctp_transport *,
1932 sctp_transport_cmd_t, sctp_sn_error_t);
1933 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
1934 struct sctp_transport *sctp_assoc_is_match(struct sctp_association *,
1936 const union sctp_addr *,
1937 const union sctp_addr *);
1938 void sctp_assoc_migrate(struct sctp_association *, struct sock *);
1939 void sctp_assoc_update(struct sctp_association *old,
1940 struct sctp_association *new);
1942 __u32 sctp_association_get_next_tsn(struct sctp_association *);
1944 void sctp_assoc_sync_pmtu(struct sock *, struct sctp_association *);
1945 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int);
1946 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int);
1947 void sctp_assoc_set_primary(struct sctp_association *,
1948 struct sctp_transport *);
1949 void sctp_assoc_del_nonprimary_peers(struct sctp_association *,
1950 struct sctp_transport *);
1951 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *,
1952 sctp_scope_t, gfp_t);
1953 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
1954 struct sctp_cookie*,
1956 int sctp_assoc_set_id(struct sctp_association *, gfp_t);
1957 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc);
1958 struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
1959 const struct sctp_association *asoc,
1961 void sctp_asconf_queue_teardown(struct sctp_association *asoc);
1963 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1964 const union sctp_addr *ss2);
1965 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
1967 /* A convenience structure to parse out SCTP specific CMSGs. */
1968 typedef struct sctp_cmsgs {
1969 struct sctp_initmsg *init;
1970 struct sctp_sndrcvinfo *srinfo;
1971 struct sctp_sndinfo *sinfo;
1974 /* Structure for tracking memory objects */
1978 } sctp_dbg_objcnt_entry_t;
1980 #endif /* __sctp_structs_h__ */