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TOMOYO Linux Cross Reference
Linux/include/net/sctp/structs.h

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  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.
  6  *
  7  * This file is part of the SCTP kernel implementation
  8  *
  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)
 13  * any later version.
 14  *
 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.
 20  *
 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/>.
 24  *
 25  * Please send any bug reports or fixes you make to the
 26  * email addresses:
 27  *    lksctp developers <linux-sctp@vger.kernel.org>
 28  *
 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>
 45  */
 46 
 47 #ifndef __sctp_structs_h__
 48 #define __sctp_structs_h__
 49 
 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 */
 63 
 64 /* A convenience structure for handling sockaddr structures.
 65  * We should wean ourselves off this.
 66  */
 67 union sctp_addr {
 68         struct sockaddr_in v4;
 69         struct sockaddr_in6 v6;
 70         struct sockaddr sa;
 71 };
 72 
 73 /* Forward declarations for data structures. */
 74 struct sctp_globals;
 75 struct sctp_endpoint;
 76 struct sctp_association;
 77 struct sctp_transport;
 78 struct sctp_packet;
 79 struct sctp_chunk;
 80 struct sctp_inq;
 81 struct sctp_outq;
 82 struct sctp_bind_addr;
 83 struct sctp_ulpq;
 84 struct sctp_ep_common;
 85 struct crypto_shash;
 86 struct sctp_stream;
 87 
 88 
 89 #include <net/sctp/tsnmap.h>
 90 #include <net/sctp/ulpevent.h>
 91 #include <net/sctp/ulpqueue.h>
 92 
 93 /* Structures useful for managing bind/connect. */
 94 
 95 struct sctp_bind_bucket {
 96         unsigned short  port;
 97         unsigned short  fastreuse;
 98         struct hlist_node       node;
 99         struct hlist_head       owner;
100         struct net      *net;
101 };
102 
103 struct sctp_bind_hashbucket {
104         spinlock_t      lock;
105         struct hlist_head       chain;
106 };
107 
108 /* Used for hashing all associations.  */
109 struct sctp_hashbucket {
110         rwlock_t        lock;
111         struct hlist_head       chain;
112 } __attribute__((__aligned__(8)));
113 
114 
115 /* The SCTP globals structure. */
116 extern struct sctp_globals {
117         /* This is a list of groups of functions for each address
118          * family that we support.
119          */
120         struct list_head address_families;
121 
122         /* This is the hash of all endpoints. */
123         struct sctp_hashbucket *ep_hashtable;
124         /* This is the sctp port control hash.  */
125         struct sctp_bind_hashbucket *port_hashtable;
126         /* This is the hash of all transports. */
127         struct rhltable transport_hashtable;
128 
129         /* Sizes of above hashtables. */
130         int ep_hashsize;
131         int port_hashsize;
132 
133         /* Default initialization values to be applied to new associations. */
134         __u16 max_instreams;
135         __u16 max_outstreams;
136 
137         /* Flag to indicate whether computing and verifying checksum
138          * is disabled. */
139         bool checksum_disable;
140 } sctp_globals;
141 
142 #define sctp_max_instreams              (sctp_globals.max_instreams)
143 #define sctp_max_outstreams             (sctp_globals.max_outstreams)
144 #define sctp_address_families           (sctp_globals.address_families)
145 #define sctp_ep_hashsize                (sctp_globals.ep_hashsize)
146 #define sctp_ep_hashtable               (sctp_globals.ep_hashtable)
147 #define sctp_port_hashsize              (sctp_globals.port_hashsize)
148 #define sctp_port_hashtable             (sctp_globals.port_hashtable)
149 #define sctp_transport_hashtable        (sctp_globals.transport_hashtable)
150 #define sctp_checksum_disable           (sctp_globals.checksum_disable)
151 
152 /* SCTP Socket type: UDP or TCP style. */
153 typedef enum {
154         SCTP_SOCKET_UDP = 0,
155         SCTP_SOCKET_UDP_HIGH_BANDWIDTH,
156         SCTP_SOCKET_TCP
157 } sctp_socket_type_t;
158 
159 /* Per socket SCTP information. */
160 struct sctp_sock {
161         /* inet_sock has to be the first member of sctp_sock */
162         struct inet_sock inet;
163         /* What kind of a socket is this? */
164         sctp_socket_type_t type;
165 
166         /* PF_ family specific functions.  */
167         struct sctp_pf *pf;
168 
169         /* Access to HMAC transform. */
170         struct crypto_shash *hmac;
171         char *sctp_hmac_alg;
172 
173         /* What is our base endpointer? */
174         struct sctp_endpoint *ep;
175 
176         struct sctp_bind_bucket *bind_hash;
177         /* Various Socket Options.  */
178         __u16 default_stream;
179         __u32 default_ppid;
180         __u16 default_flags;
181         __u32 default_context;
182         __u32 default_timetolive;
183         __u32 default_rcv_context;
184         int max_burst;
185 
186         /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
187          * the destination address every heartbeat interval. This value
188          * will be inherited by all new associations.
189          */
190         __u32 hbinterval;
191 
192         /* This is the max_retrans value for new associations. */
193         __u16 pathmaxrxt;
194 
195         /* The initial Path MTU to use for new associations. */
196         __u32 pathmtu;
197 
198         /* The default SACK delay timeout for new associations. */
199         __u32 sackdelay;
200         __u32 sackfreq;
201 
202         /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
203         __u32 param_flags;
204 
205         struct sctp_initmsg initmsg;
206         struct sctp_rtoinfo rtoinfo;
207         struct sctp_paddrparams paddrparam;
208         struct sctp_event_subscribe subscribe;
209         struct sctp_assocparams assocparams;
210 
211         int user_frag;
212 
213         __u32 autoclose;
214         __u32 adaptation_ind;
215         __u32 pd_point;
216         __u16   nodelay:1,
217                 disable_fragments:1,
218                 v4mapped:1,
219                 frag_interleave:1,
220                 recvrcvinfo:1,
221                 recvnxtinfo:1,
222                 data_ready_signalled:1;
223 
224         atomic_t pd_mode;
225         /* Receive to here while partial delivery is in effect. */
226         struct sk_buff_head pd_lobby;
227 
228         /* These must be the last fields, as they will skipped on copies,
229          * like on accept and peeloff operations
230          */
231         struct list_head auto_asconf_list;
232         int do_auto_asconf;
233 };
234 
235 static inline struct sctp_sock *sctp_sk(const struct sock *sk)
236 {
237        return (struct sctp_sock *)sk;
238 }
239 
240 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
241 {
242        return (struct sock *)sp;
243 }
244 
245 #if IS_ENABLED(CONFIG_IPV6)
246 struct sctp6_sock {
247        struct sctp_sock  sctp;
248        struct ipv6_pinfo inet6;
249 };
250 #endif /* CONFIG_IPV6 */
251 
252 
253 /* This is our APPLICATION-SPECIFIC state cookie.
254  * THIS IS NOT DICTATED BY THE SPECIFICATION.
255  */
256 /* These are the parts of an association which we send in the cookie.
257  * Most of these are straight out of:
258  * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
259  *
260  */
261 
262 struct sctp_cookie {
263 
264         /* My          : Tag expected in every inbound packet and sent
265          * Verification: in the INIT or INIT ACK chunk.
266          * Tag         :
267          */
268         __u32 my_vtag;
269 
270         /* Peer's      : Tag expected in every outbound packet except
271          * Verification: in the INIT chunk.
272          * Tag         :
273          */
274         __u32 peer_vtag;
275 
276         /* The rest of these are not from the spec, but really need to
277          * be in the cookie.
278          */
279 
280         /* My Tie Tag  : Assist in discovering a restarting association. */
281         __u32 my_ttag;
282 
283         /* Peer's Tie Tag: Assist in discovering a restarting association. */
284         __u32 peer_ttag;
285 
286         /* When does this cookie expire? */
287         ktime_t expiration;
288 
289         /* Number of inbound/outbound streams which are set
290          * and negotiated during the INIT process.
291          */
292         __u16 sinit_num_ostreams;
293         __u16 sinit_max_instreams;
294 
295         /* This is the first sequence number I used.  */
296         __u32 initial_tsn;
297 
298         /* This holds the originating address of the INIT packet.  */
299         union sctp_addr peer_addr;
300 
301         /* IG Section 2.35.3 
302          * Include the source port of the INIT-ACK
303          */
304         __u16           my_port;
305 
306         __u8 prsctp_capable;
307 
308         /* Padding for future use */
309         __u8 padding;           
310 
311         __u32 adaptation_ind;
312 
313         __u8 auth_random[sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH];
314         __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2];
315         __u8 auth_chunks[sizeof(sctp_paramhdr_t) + SCTP_AUTH_MAX_CHUNKS];
316 
317         /* This is a shim for my peer's INIT packet, followed by
318          * a copy of the raw address list of the association.
319          * The length of the raw address list is saved in the
320          * raw_addr_list_len field, which will be used at the time when
321          * the association TCB is re-constructed from the cookie.
322          */
323         __u32 raw_addr_list_len;
324         struct sctp_init_chunk peer_init[0];
325 };
326 
327 
328 /* The format of our cookie that we send to our peer. */
329 struct sctp_signed_cookie {
330         __u8 signature[SCTP_SECRET_SIZE];
331         __u32 __pad;            /* force sctp_cookie alignment to 64 bits */
332         struct sctp_cookie c;
333 } __packed;
334 
335 /* This is another convenience type to allocate memory for address
336  * params for the maximum size and pass such structures around
337  * internally.
338  */
339 union sctp_addr_param {
340         struct sctp_paramhdr p;
341         struct sctp_ipv4addr_param v4;
342         struct sctp_ipv6addr_param v6;
343 };
344 
345 /* A convenience type to allow walking through the various
346  * parameters and avoid casting all over the place.
347  */
348 union sctp_params {
349         void *v;
350         struct sctp_paramhdr *p;
351         struct sctp_cookie_preserve_param *life;
352         struct sctp_hostname_param *dns;
353         struct sctp_cookie_param *cookie;
354         struct sctp_supported_addrs_param *sat;
355         struct sctp_ipv4addr_param *v4;
356         struct sctp_ipv6addr_param *v6;
357         union sctp_addr_param *addr;
358         struct sctp_adaptation_ind_param *aind;
359         struct sctp_supported_ext_param *ext;
360         struct sctp_random_param *random;
361         struct sctp_chunks_param *chunks;
362         struct sctp_hmac_algo_param *hmac_algo;
363         struct sctp_addip_param *addip;
364 };
365 
366 /* RFC 2960.  Section 3.3.5 Heartbeat.
367  *    Heartbeat Information: variable length
368  *    The Sender-specific Heartbeat Info field should normally include
369  *    information about the sender's current time when this HEARTBEAT
370  *    chunk is sent and the destination transport address to which this
371  *    HEARTBEAT is sent (see Section 8.3).
372  */
373 typedef struct sctp_sender_hb_info {
374         struct sctp_paramhdr param_hdr;
375         union sctp_addr daddr;
376         unsigned long sent_at;
377         __u64 hb_nonce;
378 } sctp_sender_hb_info_t;
379 
380 int sctp_stream_new(struct sctp_association *asoc, gfp_t gfp);
381 int sctp_stream_init(struct sctp_association *asoc, gfp_t gfp);
382 void sctp_stream_free(struct sctp_stream *stream);
383 void sctp_stream_clear(struct sctp_stream *stream);
384 
385 /* What is the current SSN number for this stream? */
386 #define sctp_ssn_peek(stream, type, sid) \
387         ((stream)->type[sid].ssn)
388 
389 /* Return the next SSN number for this stream.  */
390 #define sctp_ssn_next(stream, type, sid) \
391         ((stream)->type[sid].ssn++)
392 
393 /* Skip over this ssn and all below. */
394 #define sctp_ssn_skip(stream, type, sid, ssn) \
395         ((stream)->type[sid].ssn = ssn + 1)
396 
397 /*
398  * Pointers to address related SCTP functions.
399  * (i.e. things that depend on the address family.)
400  */
401 struct sctp_af {
402         int             (*sctp_xmit)    (struct sk_buff *skb,
403                                          struct sctp_transport *);
404         int             (*setsockopt)   (struct sock *sk,
405                                          int level,
406                                          int optname,
407                                          char __user *optval,
408                                          unsigned int optlen);
409         int             (*getsockopt)   (struct sock *sk,
410                                          int level,
411                                          int optname,
412                                          char __user *optval,
413                                          int __user *optlen);
414         int             (*compat_setsockopt)    (struct sock *sk,
415                                          int level,
416                                          int optname,
417                                          char __user *optval,
418                                          unsigned int optlen);
419         int             (*compat_getsockopt)    (struct sock *sk,
420                                          int level,
421                                          int optname,
422                                          char __user *optval,
423                                          int __user *optlen);
424         void            (*get_dst)      (struct sctp_transport *t,
425                                          union sctp_addr *saddr,
426                                          struct flowi *fl,
427                                          struct sock *sk);
428         void            (*get_saddr)    (struct sctp_sock *sk,
429                                          struct sctp_transport *t,
430                                          struct flowi *fl);
431         void            (*copy_addrlist) (struct list_head *,
432                                           struct net_device *);
433         int             (*cmp_addr)     (const union sctp_addr *addr1,
434                                          const union sctp_addr *addr2);
435         void            (*addr_copy)    (union sctp_addr *dst,
436                                          union sctp_addr *src);
437         void            (*from_skb)     (union sctp_addr *,
438                                          struct sk_buff *skb,
439                                          int saddr);
440         void            (*from_sk)      (union sctp_addr *,
441                                          struct sock *sk);
442         void            (*from_addr_param) (union sctp_addr *,
443                                             union sctp_addr_param *,
444                                             __be16 port, int iif);
445         int             (*to_addr_param) (const union sctp_addr *,
446                                           union sctp_addr_param *); 
447         int             (*addr_valid)   (union sctp_addr *,
448                                          struct sctp_sock *,
449                                          const struct sk_buff *);
450         sctp_scope_t    (*scope) (union sctp_addr *);
451         void            (*inaddr_any)   (union sctp_addr *, __be16);
452         int             (*is_any)       (const union sctp_addr *);
453         int             (*available)    (union sctp_addr *,
454                                          struct sctp_sock *);
455         int             (*skb_iif)      (const struct sk_buff *sk);
456         int             (*is_ce)        (const struct sk_buff *sk);
457         void            (*seq_dump_addr)(struct seq_file *seq,
458                                          union sctp_addr *addr);
459         void            (*ecn_capable)(struct sock *sk);
460         __u16           net_header_len;
461         int             sockaddr_len;
462         sa_family_t     sa_family;
463         struct list_head list;
464 };
465 
466 struct sctp_af *sctp_get_af_specific(sa_family_t);
467 int sctp_register_af(struct sctp_af *);
468 
469 /* Protocol family functions. */
470 struct sctp_pf {
471         void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
472         void (*skb_msgname)  (struct sk_buff *, char *, int *);
473         int  (*af_supported) (sa_family_t, struct sctp_sock *);
474         int  (*cmp_addr) (const union sctp_addr *,
475                           const union sctp_addr *,
476                           struct sctp_sock *);
477         int  (*bind_verify) (struct sctp_sock *, union sctp_addr *);
478         int  (*send_verify) (struct sctp_sock *, union sctp_addr *);
479         int  (*supported_addrs)(const struct sctp_sock *, __be16 *);
480         struct sock *(*create_accept_sk) (struct sock *sk,
481                                           struct sctp_association *asoc,
482                                           bool kern);
483         int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr);
484         void (*to_sk_saddr)(union sctp_addr *, struct sock *sk);
485         void (*to_sk_daddr)(union sctp_addr *, struct sock *sk);
486         struct sctp_af *af;
487 };
488 
489 
490 /* Structure to track chunk fragments that have been acked, but peer
491  * fragments of the same message have not.
492  */
493 struct sctp_datamsg {
494         /* Chunks waiting to be submitted to lower layer. */
495         struct list_head chunks;
496         /* Reference counting. */
497         atomic_t refcnt;
498         /* When is this message no longer interesting to the peer? */
499         unsigned long expires_at;
500         /* Did the messenge fail to send? */
501         int send_error;
502         u8 send_failed:1,
503            can_delay;       /* should this message be Nagle delayed */
504 };
505 
506 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
507                                             struct sctp_sndrcvinfo *,
508                                             struct iov_iter *);
509 void sctp_datamsg_free(struct sctp_datamsg *);
510 void sctp_datamsg_put(struct sctp_datamsg *);
511 void sctp_chunk_fail(struct sctp_chunk *, int error);
512 int sctp_chunk_abandoned(struct sctp_chunk *);
513 
514 /* RFC2960 1.4 Key Terms
515  *
516  * o Chunk: A unit of information within an SCTP packet, consisting of
517  * a chunk header and chunk-specific content.
518  *
519  * As a matter of convenience, we remember the SCTP common header for
520  * each chunk as well as a few other header pointers...
521  */
522 struct sctp_chunk {
523         struct list_head list;
524 
525         atomic_t refcnt;
526 
527         /* How many times this chunk have been sent, for prsctp RTX policy */
528         int sent_count;
529 
530         /* This is our link to the per-transport transmitted list.  */
531         struct list_head transmitted_list;
532 
533         /* This field is used by chunks that hold fragmented data.
534          * For the first fragment this is the list that holds the rest of
535          * fragments. For the remaining fragments, this is the link to the
536          * frag_list maintained in the first fragment.
537          */
538         struct list_head frag_list;
539 
540         /* This points to the sk_buff containing the actual data.  */
541         struct sk_buff *skb;
542 
543         /* In case of GSO packets, this will store the head one */
544         struct sk_buff *head_skb;
545 
546         /* These are the SCTP headers by reverse order in a packet.
547          * Note that some of these may happen more than once.  In that
548          * case, we point at the "current" one, whatever that means
549          * for that level of header.
550          */
551 
552         /* We point this at the FIRST TLV parameter to chunk_hdr.  */
553         union sctp_params param_hdr;
554         union {
555                 __u8 *v;
556                 struct sctp_datahdr *data_hdr;
557                 struct sctp_inithdr *init_hdr;
558                 struct sctp_sackhdr *sack_hdr;
559                 struct sctp_heartbeathdr *hb_hdr;
560                 struct sctp_sender_hb_info *hbs_hdr;
561                 struct sctp_shutdownhdr *shutdown_hdr;
562                 struct sctp_signed_cookie *cookie_hdr;
563                 struct sctp_ecnehdr *ecne_hdr;
564                 struct sctp_cwrhdr *ecn_cwr_hdr;
565                 struct sctp_errhdr *err_hdr;
566                 struct sctp_addiphdr *addip_hdr;
567                 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
568                 struct sctp_authhdr *auth_hdr;
569         } subh;
570 
571         __u8 *chunk_end;
572 
573         struct sctp_chunkhdr *chunk_hdr;
574         struct sctphdr *sctp_hdr;
575 
576         /* This needs to be recoverable for SCTP_SEND_FAILED events. */
577         struct sctp_sndrcvinfo sinfo;
578 
579         /* Which association does this belong to?  */
580         struct sctp_association *asoc;
581 
582         /* What endpoint received this chunk? */
583         struct sctp_ep_common *rcvr;
584 
585         /* We fill this in if we are calculating RTT. */
586         unsigned long sent_at;
587 
588         /* What is the origin IP address for this chunk?  */
589         union sctp_addr source;
590         /* Destination address for this chunk. */
591         union sctp_addr dest;
592 
593         /* For outbound message, track all fragments for SEND_FAILED. */
594         struct sctp_datamsg *msg;
595 
596         /* For an inbound chunk, this tells us where it came from.
597          * For an outbound chunk, it tells us where we'd like it to
598          * go.  It is NULL if we have no preference.
599          */
600         struct sctp_transport *transport;
601 
602         /* SCTP-AUTH:  For the special case inbound processing of COOKIE-ECHO
603          * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
604          * spec violates the principle premis that all chunks are processed
605          * in order.
606          */
607         struct sk_buff *auth_chunk;
608 
609 #define SCTP_CAN_FRTX 0x0
610 #define SCTP_NEED_FRTX 0x1
611 #define SCTP_DONT_FRTX 0x2
612         __u16   rtt_in_progress:1,      /* This chunk used for RTT calc? */
613                 has_tsn:1,              /* Does this chunk have a TSN yet? */
614                 has_ssn:1,              /* Does this chunk have a SSN yet? */
615                 singleton:1,            /* Only chunk in the packet? */
616                 end_of_packet:1,        /* Last chunk in the packet? */
617                 ecn_ce_done:1,          /* Have we processed the ECN CE bit? */
618                 pdiscard:1,             /* Discard the whole packet now? */
619                 tsn_gap_acked:1,        /* Is this chunk acked by a GAP ACK? */
620                 data_accepted:1,        /* At least 1 chunk accepted */
621                 auth:1,                 /* IN: was auth'ed | OUT: needs auth */
622                 has_asconf:1,           /* IN: have seen an asconf before */
623                 tsn_missing_report:2,   /* Data chunk missing counter. */
624                 fast_retransmit:2;      /* Is this chunk fast retransmitted? */
625 };
626 
627 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1)
628 void sctp_chunk_hold(struct sctp_chunk *);
629 void sctp_chunk_put(struct sctp_chunk *);
630 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len,
631                           struct iov_iter *from);
632 void sctp_chunk_free(struct sctp_chunk *);
633 void  *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
634 struct sctp_chunk *sctp_chunkify(struct sk_buff *,
635                                  const struct sctp_association *,
636                                  struct sock *, gfp_t gfp);
637 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
638                      union sctp_addr *);
639 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
640 
641 enum {
642         SCTP_ADDR_NEW,          /* new address added to assoc/ep */
643         SCTP_ADDR_SRC,          /* address can be used as source */
644         SCTP_ADDR_DEL,          /* address about to be deleted */
645 };
646 
647 /* This is a structure for holding either an IPv6 or an IPv4 address.  */
648 struct sctp_sockaddr_entry {
649         struct list_head list;
650         struct rcu_head rcu;
651         union sctp_addr a;
652         __u8 state;
653         __u8 valid;
654 };
655 
656 #define SCTP_ADDRESS_TICK_DELAY 500
657 
658 typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *);
659 
660 /* This structure holds lists of chunks as we are assembling for
661  * transmission.
662  */
663 struct sctp_packet {
664         /* These are the SCTP header values (host order) for the packet. */
665         __u16 source_port;
666         __u16 destination_port;
667         __u32 vtag;
668 
669         /* This contains the payload chunks.  */
670         struct list_head chunk_list;
671 
672         /* This is the overhead of the sctp and ip headers. */
673         size_t overhead;
674         /* This is the total size of all chunks INCLUDING padding.  */
675         size_t size;
676         /* This is the maximum size this packet may have */
677         size_t max_size;
678 
679         /* The packet is destined for this transport address.
680          * The function we finally use to pass down to the next lower
681          * layer lives in the transport structure.
682          */
683         struct sctp_transport *transport;
684 
685         /* pointer to the auth chunk for this packet */
686         struct sctp_chunk *auth;
687 
688         u8  has_cookie_echo:1,  /* This packet contains a COOKIE-ECHO chunk. */
689             has_sack:1,         /* This packet contains a SACK chunk. */
690             has_auth:1,         /* This packet contains an AUTH chunk */
691             has_data:1,         /* This packet contains at least 1 DATA chunk */
692             ipfragok:1;         /* So let ip fragment this packet */
693 };
694 
695 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *,
696                       __u16 sport, __u16 dport);
697 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
698 sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *,
699                                        struct sctp_chunk *, int, gfp_t);
700 sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *,
701                                      struct sctp_chunk *);
702 int sctp_packet_transmit(struct sctp_packet *, gfp_t);
703 void sctp_packet_free(struct sctp_packet *);
704 
705 static inline int sctp_packet_empty(struct sctp_packet *packet)
706 {
707         return packet->size == packet->overhead;
708 }
709 
710 /* This represents a remote transport address.
711  * For local transport addresses, we just use union sctp_addr.
712  *
713  * RFC2960 Section 1.4 Key Terms
714  *
715  *   o  Transport address:  A Transport Address is traditionally defined
716  *      by Network Layer address, Transport Layer protocol and Transport
717  *      Layer port number.  In the case of SCTP running over IP, a
718  *      transport address is defined by the combination of an IP address
719  *      and an SCTP port number (where SCTP is the Transport protocol).
720  *
721  * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
722  *
723  *   o  The sender keeps a separate congestion control parameter set for
724  *      each of the destination addresses it can send to (not each
725  *      source-destination pair but for each destination).  The parameters
726  *      should decay if the address is not used for a long enough time
727  *      period.
728  *
729  */
730 struct sctp_transport {
731         /* A list of transports. */
732         struct list_head transports;
733         struct rhlist_head node;
734 
735         /* Reference counting. */
736         atomic_t refcnt;
737                 /* RTO-Pending : A flag used to track if one of the DATA
738                  *              chunks sent to this address is currently being
739                  *              used to compute a RTT. If this flag is 0,
740                  *              the next DATA chunk sent to this destination
741                  *              should be used to compute a RTT and this flag
742                  *              should be set. Every time the RTT
743                  *              calculation completes (i.e. the DATA chunk
744                  *              is SACK'd) clear this flag.
745                  */
746         __u32   rto_pending:1,
747 
748                 /*
749                  * hb_sent : a flag that signals that we have a pending
750                  * heartbeat.
751                  */
752                 hb_sent:1,
753 
754                 /* Is the Path MTU update pending on this tranport */
755                 pmtu_pending:1,
756 
757                 dst_pending_confirm:1,  /* need to confirm neighbour */
758 
759                 /* Has this transport moved the ctsn since we last sacked */
760                 sack_generation:1;
761         u32 dst_cookie;
762 
763         struct flowi fl;
764 
765         /* This is the peer's IP address and port. */
766         union sctp_addr ipaddr;
767 
768         /* These are the functions we call to handle LLP stuff.  */
769         struct sctp_af *af_specific;
770 
771         /* Which association do we belong to?  */
772         struct sctp_association *asoc;
773 
774         /* RFC2960
775          *
776          * 12.3 Per Transport Address Data
777          *
778          * For each destination transport address in the peer's
779          * address list derived from the INIT or INIT ACK chunk, a
780          * number of data elements needs to be maintained including:
781          */
782         /* RTO         : The current retransmission timeout value.  */
783         unsigned long rto;
784 
785         __u32 rtt;              /* This is the most recent RTT.  */
786 
787         /* RTTVAR      : The current RTT variation.  */
788         __u32 rttvar;
789 
790         /* SRTT        : The current smoothed round trip time.  */
791         __u32 srtt;
792 
793         /*
794          * These are the congestion stats.
795          */
796         /* cwnd        : The current congestion window.  */
797         __u32 cwnd;               /* This is the actual cwnd.  */
798 
799         /* ssthresh    : The current slow start threshold value.  */
800         __u32 ssthresh;
801 
802         /* partial     : The tracking method for increase of cwnd when in
803          * bytes acked : congestion avoidance mode (see Section 6.2.2)
804          */
805         __u32 partial_bytes_acked;
806 
807         /* Data that has been sent, but not acknowledged. */
808         __u32 flight_size;
809 
810         __u32 burst_limited;    /* Holds old cwnd when max.burst is applied */
811 
812         /* Destination */
813         struct dst_entry *dst;
814         /* Source address. */
815         union sctp_addr saddr;
816 
817         /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
818          * the destination address every heartbeat interval.
819          */
820         unsigned long hbinterval;
821 
822         /* SACK delay timeout */
823         unsigned long sackdelay;
824         __u32 sackfreq;
825 
826         /* When was the last time that we heard from this transport? We use
827          * this to pick new active and retran paths.
828          */
829         ktime_t last_time_heard;
830 
831         /* When was the last time that we sent a chunk using this
832          * transport? We use this to check for idle transports
833          */
834         unsigned long last_time_sent;
835 
836         /* Last time(in jiffies) when cwnd is reduced due to the congestion
837          * indication based on ECNE chunk.
838          */
839         unsigned long last_time_ecne_reduced;
840 
841         /* This is the max_retrans value for the transport and will
842          * be initialized from the assocs value.  This can be changed
843          * using the SCTP_SET_PEER_ADDR_PARAMS socket option.
844          */
845         __u16 pathmaxrxt;
846 
847         /* This is the partially failed retrans value for the transport
848          * and will be initialized from the assocs value.  This can be changed
849          * using the SCTP_PEER_ADDR_THLDS socket option
850          */
851         int pf_retrans;
852         /* PMTU       : The current known path MTU.  */
853         __u32 pathmtu;
854 
855         /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
856         __u32 param_flags;
857 
858         /* The number of times INIT has been sent on this transport. */
859         int init_sent_count;
860 
861         /* state       : The current state of this destination,
862          *             : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
863          */
864         int state;
865 
866         /* These are the error stats for this destination.  */
867 
868         /* Error count : The current error count for this destination.  */
869         unsigned short error_count;
870 
871         /* Per         : A timer used by each destination.
872          * Destination :
873          * Timer       :
874          *
875          * [Everywhere else in the text this is called T3-rtx. -ed]
876          */
877         struct timer_list T3_rtx_timer;
878 
879         /* Heartbeat timer is per destination. */
880         struct timer_list hb_timer;
881 
882         /* Timer to handle ICMP proto unreachable envets */
883         struct timer_list proto_unreach_timer;
884 
885         /* Timer to handler reconf chunk rtx */
886         struct timer_list reconf_timer;
887 
888         /* Since we're using per-destination retransmission timers
889          * (see above), we're also using per-destination "transmitted"
890          * queues.  This probably ought to be a private struct
891          * accessible only within the outqueue, but it's not, yet.
892          */
893         struct list_head transmitted;
894 
895         /* We build bundle-able packets for this transport here.  */
896         struct sctp_packet packet;
897 
898         /* This is the list of transports that have chunks to send.  */
899         struct list_head send_ready;
900 
901         /* State information saved for SFR_CACC algorithm. The key
902          * idea in SFR_CACC is to maintain state at the sender on a
903          * per-destination basis when a changeover happens.
904          *      char changeover_active;
905          *      char cycling_changeover;
906          *      __u32 next_tsn_at_change;
907          *      char cacc_saw_newack;
908          */
909         struct {
910                 /* An unsigned integer, which stores the next TSN to be
911                  * used by the sender, at the moment of changeover.
912                  */
913                 __u32 next_tsn_at_change;
914 
915                 /* A flag which indicates the occurrence of a changeover */
916                 char changeover_active;
917 
918                 /* A flag which indicates whether the change of primary is
919                  * the first switch to this destination address during an
920                  * active switch.
921                  */
922                 char cycling_changeover;
923 
924                 /* A temporary flag, which is used during the processing of
925                  * a SACK to estimate the causative TSN(s)'s group.
926                  */
927                 char cacc_saw_newack;
928         } cacc;
929 
930         /* 64-bit random number sent with heartbeat. */
931         __u64 hb_nonce;
932 
933         struct rcu_head rcu;
934 };
935 
936 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *,
937                                           gfp_t);
938 void sctp_transport_set_owner(struct sctp_transport *,
939                               struct sctp_association *);
940 void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
941                           struct sctp_sock *);
942 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk);
943 void sctp_transport_free(struct sctp_transport *);
944 void sctp_transport_reset_t3_rtx(struct sctp_transport *);
945 void sctp_transport_reset_hb_timer(struct sctp_transport *);
946 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport);
947 int sctp_transport_hold(struct sctp_transport *);
948 void sctp_transport_put(struct sctp_transport *);
949 void sctp_transport_update_rto(struct sctp_transport *, __u32);
950 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
951 void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t);
952 void sctp_transport_burst_limited(struct sctp_transport *);
953 void sctp_transport_burst_reset(struct sctp_transport *);
954 unsigned long sctp_transport_timeout(struct sctp_transport *);
955 void sctp_transport_reset(struct sctp_transport *t);
956 void sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu);
957 void sctp_transport_immediate_rtx(struct sctp_transport *);
958 void sctp_transport_dst_release(struct sctp_transport *t);
959 void sctp_transport_dst_confirm(struct sctp_transport *t);
960 
961 
962 /* This is the structure we use to queue packets as they come into
963  * SCTP.  We write packets to it and read chunks from it.
964  */
965 struct sctp_inq {
966         /* This is actually a queue of sctp_chunk each
967          * containing a partially decoded packet.
968          */
969         struct list_head in_chunk_list;
970         /* This is the packet which is currently off the in queue and is
971          * being worked on through the inbound chunk processing.
972          */
973         struct sctp_chunk *in_progress;
974 
975         /* This is the delayed task to finish delivering inbound
976          * messages.
977          */
978         struct work_struct immediate;
979 };
980 
981 void sctp_inq_init(struct sctp_inq *);
982 void sctp_inq_free(struct sctp_inq *);
983 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
984 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
985 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *);
986 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t);
987 
988 /* This is the structure we use to hold outbound chunks.  You push
989  * chunks in and they automatically pop out the other end as bundled
990  * packets (it calls (*output_handler)()).
991  *
992  * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
993  * and 8.2 of the v13 draft.
994  *
995  * It handles retransmissions.  The connection to the timeout portion
996  * of the state machine is through sctp_..._timeout() and timeout_handler.
997  *
998  * If you feed it SACKs, it will eat them.
999  *
1000  * If you give it big chunks, it will fragment them.
1001  *
1002  * It assigns TSN's to data chunks.  This happens at the last possible
1003  * instant before transmission.
1004  *
1005  * When free()'d, it empties itself out via output_handler().
1006  */
1007 struct sctp_outq {
1008         struct sctp_association *asoc;
1009 
1010         /* Data pending that has never been transmitted.  */
1011         struct list_head out_chunk_list;
1012 
1013         unsigned int out_qlen;  /* Total length of queued data chunks. */
1014 
1015         /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1016         unsigned int error;
1017 
1018         /* These are control chunks we want to send.  */
1019         struct list_head control_chunk_list;
1020 
1021         /* These are chunks that have been sacked but are above the
1022          * CTSN, or cumulative tsn ack point.
1023          */
1024         struct list_head sacked;
1025 
1026         /* Put chunks on this list to schedule them for
1027          * retransmission.
1028          */
1029         struct list_head retransmit;
1030 
1031         /* Put chunks on this list to save them for FWD TSN processing as
1032          * they were abandoned.
1033          */
1034         struct list_head abandoned;
1035 
1036         /* How many unackd bytes do we have in-flight?  */
1037         __u32 outstanding_bytes;
1038 
1039         /* Are we doing fast-rtx on this queue */
1040         char fast_rtx;
1041 
1042         /* Corked? */
1043         char cork;
1044 };
1045 
1046 void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1047 void sctp_outq_teardown(struct sctp_outq *);
1048 void sctp_outq_free(struct sctp_outq*);
1049 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t);
1050 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *);
1051 int sctp_outq_is_empty(const struct sctp_outq *);
1052 void sctp_outq_restart(struct sctp_outq *);
1053 
1054 void sctp_retransmit(struct sctp_outq *, struct sctp_transport *,
1055                      sctp_retransmit_reason_t);
1056 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1057 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp);
1058 void sctp_prsctp_prune(struct sctp_association *asoc,
1059                        struct sctp_sndrcvinfo *sinfo, int msg_len);
1060 /* Uncork and flush an outqueue.  */
1061 static inline void sctp_outq_cork(struct sctp_outq *q)
1062 {
1063         q->cork = 1;
1064 }
1065 
1066 /* SCTP skb control block.
1067  * sctp_input_cb is currently used on rx and sock rx queue
1068  */
1069 struct sctp_input_cb {
1070         union {
1071                 struct inet_skb_parm    h4;
1072 #if IS_ENABLED(CONFIG_IPV6)
1073                 struct inet6_skb_parm   h6;
1074 #endif
1075         } header;
1076         struct sctp_chunk *chunk;
1077         struct sctp_af *af;
1078 };
1079 #define SCTP_INPUT_CB(__skb)    ((struct sctp_input_cb *)&((__skb)->cb[0]))
1080 
1081 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb)
1082 {
1083         const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk;
1084 
1085         return chunk->head_skb ? : skb;
1086 }
1087 
1088 /* These bind address data fields common between endpoints and associations */
1089 struct sctp_bind_addr {
1090 
1091         /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1092          *
1093          * SCTP Port:   The local SCTP port number the endpoint is
1094          *              bound to.
1095          */
1096         __u16 port;
1097 
1098         /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1099          *
1100          * Address List: The list of IP addresses that this instance
1101          *      has bound.  This information is passed to one's
1102          *      peer(s) in INIT and INIT ACK chunks.
1103          */
1104         struct list_head address_list;
1105 };
1106 
1107 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1108 void sctp_bind_addr_free(struct sctp_bind_addr *);
1109 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest,
1110                         const struct sctp_bind_addr *src,
1111                         sctp_scope_t scope, gfp_t gfp,
1112                         int flags);
1113 int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
1114                         const struct sctp_bind_addr *src,
1115                         gfp_t gfp);
1116 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1117                        int new_size, __u8 addr_state, gfp_t gfp);
1118 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1119 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1120                          struct sctp_sock *);
1121 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *,
1122                          struct sctp_sock *, struct sctp_sock *);
1123 int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
1124                          const union sctp_addr *addr);
1125 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr   *bp,
1126                                         const union sctp_addr   *addrs,
1127                                         int                     addrcnt,
1128                                         struct sctp_sock        *opt);
1129 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1130                                          int *addrs_len,
1131                                          gfp_t gfp);
1132 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1133                            __u16 port, gfp_t gfp);
1134 
1135 sctp_scope_t sctp_scope(const union sctp_addr *);
1136 int sctp_in_scope(struct net *net, const union sctp_addr *addr, const sctp_scope_t scope);
1137 int sctp_is_any(struct sock *sk, const union sctp_addr *addr);
1138 int sctp_is_ep_boundall(struct sock *sk);
1139 
1140 
1141 /* What type of endpoint?  */
1142 typedef enum {
1143         SCTP_EP_TYPE_SOCKET,
1144         SCTP_EP_TYPE_ASSOCIATION,
1145 } sctp_endpoint_type_t;
1146 
1147 /*
1148  * A common base class to bridge the implmentation view of a
1149  * socket (usually listening) endpoint versus an association's
1150  * local endpoint.
1151  * This common structure is useful for several purposes:
1152  *   1) Common interface for lookup routines.
1153  *      a) Subfunctions work for either endpoint or association
1154  *      b) Single interface to lookup allows hiding the lookup lock rather
1155  *         than acquiring it externally.
1156  *   2) Common interface for the inbound chunk handling/state machine.
1157  *   3) Common object handling routines for reference counting, etc.
1158  *   4) Disentangle association lookup from endpoint lookup, where we
1159  *      do not have to find our endpoint to find our association.
1160  *
1161  */
1162 
1163 struct sctp_ep_common {
1164         /* Fields to help us manage our entries in the hash tables. */
1165         struct hlist_node node;
1166         int hashent;
1167 
1168         /* Runtime type information.  What kind of endpoint is this? */
1169         sctp_endpoint_type_t type;
1170 
1171         /* Some fields to help us manage this object.
1172          *   refcnt   - Reference count access to this object.
1173          *   dead     - Do not attempt to use this object.
1174          */
1175         atomic_t    refcnt;
1176         bool        dead;
1177 
1178         /* What socket does this endpoint belong to?  */
1179         struct sock *sk;
1180 
1181         /* This is where we receive inbound chunks.  */
1182         struct sctp_inq   inqueue;
1183 
1184         /* This substructure includes the defining parameters of the
1185          * endpoint:
1186          * bind_addr.port is our shared port number.
1187          * bind_addr.address_list is our set of local IP addresses.
1188          */
1189         struct sctp_bind_addr bind_addr;
1190 };
1191 
1192 
1193 /* RFC Section 1.4 Key Terms
1194  *
1195  * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1196  *   multi-homed host, an SCTP endpoint is represented to its peers as a
1197  *   combination of a set of eligible destination transport addresses to
1198  *   which SCTP packets can be sent and a set of eligible source
1199  *   transport addresses from which SCTP packets can be received.
1200  *   All transport addresses used by an SCTP endpoint must use the
1201  *   same port number, but can use multiple IP addresses. A transport
1202  *   address used by an SCTP endpoint must not be used by another
1203  *   SCTP endpoint. In other words, a transport address is unique
1204  *   to an SCTP endpoint.
1205  *
1206  * From an implementation perspective, each socket has one of these.
1207  * A TCP-style socket will have exactly one association on one of
1208  * these.  An UDP-style socket will have multiple associations hanging
1209  * off one of these.
1210  */
1211 
1212 struct sctp_endpoint {
1213         /* Common substructure for endpoint and association. */
1214         struct sctp_ep_common base;
1215 
1216         /* Associations: A list of current associations and mappings
1217          *            to the data consumers for each association. This
1218          *            may be in the form of a hash table or other
1219          *            implementation dependent structure. The data
1220          *            consumers may be process identification
1221          *            information such as file descriptors, named pipe
1222          *            pointer, or table pointers dependent on how SCTP
1223          *            is implemented.
1224          */
1225         /* This is really a list of struct sctp_association entries. */
1226         struct list_head asocs;
1227 
1228         /* Secret Key: A secret key used by this endpoint to compute
1229          *            the MAC.  This SHOULD be a cryptographic quality
1230          *            random number with a sufficient length.
1231          *            Discussion in [RFC1750] can be helpful in
1232          *            selection of the key.
1233          */
1234         __u8 secret_key[SCTP_SECRET_SIZE];
1235 
1236         /* digest:  This is a digest of the sctp cookie.  This field is
1237          *          only used on the receive path when we try to validate
1238          *          that the cookie has not been tampered with.  We put
1239          *          this here so we pre-allocate this once and can re-use
1240          *          on every receive.
1241          */
1242         __u8 *digest;
1243  
1244         /* sendbuf acct. policy.        */
1245         __u32 sndbuf_policy;
1246 
1247         /* rcvbuf acct. policy. */
1248         __u32 rcvbuf_policy;
1249 
1250         /* SCTP AUTH: array of the HMACs that will be allocated
1251          * we need this per association so that we don't serialize
1252          */
1253         struct crypto_shash **auth_hmacs;
1254 
1255         /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1256          struct sctp_hmac_algo_param *auth_hmacs_list;
1257 
1258         /* SCTP-AUTH: chunks to authenticate encoded into parameter */
1259         struct sctp_chunks_param *auth_chunk_list;
1260 
1261         /* SCTP-AUTH: endpoint shared keys */
1262         struct list_head endpoint_shared_keys;
1263         __u16 active_key_id;
1264         __u8  auth_enable:1,
1265               prsctp_enable:1,
1266               reconf_enable:1;
1267 
1268         __u8  strreset_enable;
1269 };
1270 
1271 /* Recover the outter endpoint structure. */
1272 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1273 {
1274         struct sctp_endpoint *ep;
1275 
1276         ep = container_of(base, struct sctp_endpoint, base);
1277         return ep;
1278 }
1279 
1280 /* These are function signatures for manipulating endpoints.  */
1281 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1282 void sctp_endpoint_free(struct sctp_endpoint *);
1283 void sctp_endpoint_put(struct sctp_endpoint *);
1284 void sctp_endpoint_hold(struct sctp_endpoint *);
1285 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1286 struct sctp_association *sctp_endpoint_lookup_assoc(
1287         const struct sctp_endpoint *ep,
1288         const union sctp_addr *paddr,
1289         struct sctp_transport **);
1290 int sctp_endpoint_is_peeled_off(struct sctp_endpoint *,
1291                                 const union sctp_addr *);
1292 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1293                                         struct net *, const union sctp_addr *);
1294 int sctp_has_association(struct net *net, const union sctp_addr *laddr,
1295                          const union sctp_addr *paddr);
1296 
1297 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep,
1298                      const struct sctp_association *asoc,
1299                      sctp_cid_t, sctp_init_chunk_t *peer_init,
1300                      struct sctp_chunk *chunk, struct sctp_chunk **err_chunk);
1301 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk,
1302                       const union sctp_addr *peer,
1303                       sctp_init_chunk_t *init, gfp_t gfp);
1304 __u32 sctp_generate_tag(const struct sctp_endpoint *);
1305 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
1306 
1307 struct sctp_inithdr_host {
1308         __u32 init_tag;
1309         __u32 a_rwnd;
1310         __u16 num_outbound_streams;
1311         __u16 num_inbound_streams;
1312         __u32 initial_tsn;
1313 };
1314 
1315 struct sctp_stream_out {
1316         __u16   ssn;
1317         __u8    state;
1318 };
1319 
1320 struct sctp_stream_in {
1321         __u16   ssn;
1322 };
1323 
1324 struct sctp_stream {
1325         struct sctp_stream_out *out;
1326         struct sctp_stream_in *in;
1327         __u16 outcnt;
1328         __u16 incnt;
1329 };
1330 
1331 #define SCTP_STREAM_CLOSED              0x00
1332 #define SCTP_STREAM_OPEN                0x01
1333 
1334 /* SCTP_GET_ASSOC_STATS counters */
1335 struct sctp_priv_assoc_stats {
1336         /* Maximum observed rto in the association during subsequent
1337          * observations. Value is set to 0 if no RTO measurement took place
1338          * The transport where the max_rto was observed is returned in
1339          * obs_rto_ipaddr
1340          */
1341         struct sockaddr_storage obs_rto_ipaddr;
1342         __u64 max_obs_rto;
1343         /* Total In and Out SACKs received and sent */
1344         __u64 isacks;
1345         __u64 osacks;
1346         /* Total In and Out packets received and sent */
1347         __u64 opackets;
1348         __u64 ipackets;
1349         /* Total retransmitted chunks */
1350         __u64 rtxchunks;
1351         /* TSN received > next expected */
1352         __u64 outofseqtsns;
1353         /* Duplicate Chunks received */
1354         __u64 idupchunks;
1355         /* Gap Ack Blocks received */
1356         __u64 gapcnt;
1357         /* Unordered data chunks sent and received */
1358         __u64 ouodchunks;
1359         __u64 iuodchunks;
1360         /* Ordered data chunks sent and received */
1361         __u64 oodchunks;
1362         __u64 iodchunks;
1363         /* Control chunks sent and received */
1364         __u64 octrlchunks;
1365         __u64 ictrlchunks;
1366 };
1367 
1368 /* RFC2960
1369  *
1370  * 12. Recommended Transmission Control Block (TCB) Parameters
1371  *
1372  * This section details a recommended set of parameters that should
1373  * be contained within the TCB for an implementation. This section is
1374  * for illustrative purposes and should not be deemed as requirements
1375  * on an implementation or as an exhaustive list of all parameters
1376  * inside an SCTP TCB. Each implementation may need its own additional
1377  * parameters for optimization.
1378  */
1379 
1380 
1381 /* Here we have information about each individual association. */
1382 struct sctp_association {
1383 
1384         /* A base structure common to endpoint and association.
1385          * In this context, it represents the associations's view
1386          * of the local endpoint of the association.
1387          */
1388         struct sctp_ep_common base;
1389 
1390         /* Associations on the same socket. */
1391         struct list_head asocs;
1392 
1393         /* association id. */
1394         sctp_assoc_t assoc_id;
1395 
1396         /* This is our parent endpoint.  */
1397         struct sctp_endpoint *ep;
1398 
1399         /* These are those association elements needed in the cookie.  */
1400         struct sctp_cookie c;
1401 
1402         /* This is all information about our peer.  */
1403         struct {
1404                 /* transport_addr_list
1405                  *
1406                  * Peer        : A list of SCTP transport addresses that the
1407                  * Transport   : peer is bound to. This information is derived
1408                  * Address     : from the INIT or INIT ACK and is used to
1409                  * List        : associate an inbound packet with a given
1410                  *             : association. Normally this information is
1411                  *             : hashed or keyed for quick lookup and access
1412                  *             : of the TCB.
1413                  *             : The list is also initialized with the list
1414                  *             : of addresses passed with the sctp_connectx()
1415                  *             : call.
1416                  *
1417                  * It is a list of SCTP_transport's.
1418                  */
1419                 struct list_head transport_addr_list;
1420 
1421                 /* rwnd
1422                  *
1423                  * Peer Rwnd   : Current calculated value of the peer's rwnd.
1424                  */
1425                 __u32 rwnd;
1426 
1427                 /* transport_count
1428                  *
1429                  * Peer        : A count of the number of peer addresses
1430                  * Transport   : in the Peer Transport Address List.
1431                  * Address     :
1432                  * Count       :
1433                  */
1434                 __u16 transport_count;
1435 
1436                 /* port
1437                  *   The transport layer port number.
1438                  */
1439                 __u16 port;
1440 
1441                 /* primary_path
1442                  *
1443                  * Primary     : This is the current primary destination
1444                  * Path        : transport address of the peer endpoint.  It
1445                  *             : may also specify a source transport address
1446                  *             : on this endpoint.
1447                  *
1448                  * All of these paths live on transport_addr_list.
1449                  *
1450                  * At the bakeoffs, we discovered that the intent of
1451                  * primaryPath is that it only changes when the ULP
1452                  * asks to have it changed.  We add the activePath to
1453                  * designate the connection we are currently using to
1454                  * transmit new data and most control chunks.
1455                  */
1456                 struct sctp_transport *primary_path;
1457 
1458                 /* Cache the primary path address here, when we
1459                  * need a an address for msg_name.
1460                  */
1461                 union sctp_addr primary_addr;
1462 
1463                 /* active_path
1464                  *   The path that we are currently using to
1465                  *   transmit new data and most control chunks.
1466                  */
1467                 struct sctp_transport *active_path;
1468 
1469                 /* retran_path
1470                  *
1471                  * RFC2960 6.4 Multi-homed SCTP Endpoints
1472                  * ...
1473                  * Furthermore, when its peer is multi-homed, an
1474                  * endpoint SHOULD try to retransmit a chunk to an
1475                  * active destination transport address that is
1476                  * different from the last destination address to
1477                  * which the DATA chunk was sent.
1478                  */
1479                 struct sctp_transport *retran_path;
1480 
1481                 /* Pointer to last transport I have sent on.  */
1482                 struct sctp_transport *last_sent_to;
1483 
1484                 /* This is the last transport I have received DATA on.  */
1485                 struct sctp_transport *last_data_from;
1486 
1487                 /*
1488                  * Mapping  An array of bits or bytes indicating which out of
1489                  * Array    order TSN's have been received (relative to the
1490                  *          Last Rcvd TSN). If no gaps exist, i.e. no out of
1491                  *          order packets have been received, this array
1492                  *          will be set to all zero. This structure may be
1493                  *          in the form of a circular buffer or bit array.
1494                  *
1495                  * Last Rcvd   : This is the last TSN received in
1496                  * TSN         : sequence. This value is set initially by
1497                  *             : taking the peer's Initial TSN, received in
1498                  *             : the INIT or INIT ACK chunk, and subtracting
1499                  *             : one from it.
1500                  *
1501                  * Throughout most of the specification this is called the
1502                  * "Cumulative TSN ACK Point".  In this case, we
1503                  * ignore the advice in 12.2 in favour of the term
1504                  * used in the bulk of the text.  This value is hidden
1505                  * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1506                  */
1507                 struct sctp_tsnmap tsn_map;
1508 
1509                 /* This mask is used to disable sending the ASCONF chunk
1510                  * with specified parameter to peer.
1511                  */
1512                 __be16 addip_disabled_mask;
1513 
1514                 /* These are capabilities which our peer advertised.  */
1515                 __u8    ecn_capable:1,      /* Can peer do ECN? */
1516                         ipv4_address:1,     /* Peer understands IPv4 addresses? */
1517                         ipv6_address:1,     /* Peer understands IPv6 addresses? */
1518                         hostname_address:1, /* Peer understands DNS addresses? */
1519                         asconf_capable:1,   /* Does peer support ADDIP? */
1520                         prsctp_capable:1,   /* Can peer do PR-SCTP? */
1521                         reconf_capable:1,   /* Can peer do RE-CONFIG? */
1522                         auth_capable:1;     /* Is peer doing SCTP-AUTH? */
1523 
1524                 /* sack_needed : This flag indicates if the next received
1525                  *             : packet is to be responded to with a
1526                  *             : SACK. This is initialized to 0.  When a packet
1527                  *             : is received sack_cnt is incremented. If this value
1528                  *             : reaches 2 or more, a SACK is sent and the
1529                  *             : value is reset to 0. Note: This is used only
1530                  *             : when no DATA chunks are received out of
1531                  *             : order.  When DATA chunks are out of order,
1532                  *             : SACK's are not delayed (see Section 6).
1533                  */
1534                 __u8    sack_needed:1,     /* Do we need to sack the peer? */
1535                         sack_generation:1,
1536                         zero_window_announced:1;
1537                 __u32   sack_cnt;
1538 
1539                 __u32   adaptation_ind;  /* Adaptation Code point. */
1540 
1541                 struct sctp_inithdr_host i;
1542                 void *cookie;
1543                 int cookie_len;
1544 
1545                 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1546                  * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1547                  * Initial TSN Value minus 1
1548                  */
1549                 __u32 addip_serial;
1550 
1551                 /* SCTP-AUTH: We need to know pears random number, hmac list
1552                  * and authenticated chunk list.  All that is part of the
1553                  * cookie and these are just pointers to those locations
1554                  */
1555                 sctp_random_param_t *peer_random;
1556                 sctp_chunks_param_t *peer_chunks;
1557                 sctp_hmac_algo_param_t *peer_hmacs;
1558         } peer;
1559 
1560         /* State       : A state variable indicating what state the
1561          *             : association is in, i.e. COOKIE-WAIT,
1562          *             : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1563          *             : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1564          *
1565          *              Note: No "CLOSED" state is illustrated since if a
1566          *              association is "CLOSED" its TCB SHOULD be removed.
1567          *
1568          *              In this implementation we DO have a CLOSED
1569          *              state which is used during initiation and shutdown.
1570          *
1571          *              State takes values from SCTP_STATE_*.
1572          */
1573         sctp_state_t state;
1574 
1575         /* Overall     : The overall association error count.
1576          * Error Count : [Clear this any time I get something.]
1577          */
1578         int overall_error_count;
1579 
1580         /* The cookie life I award for any cookie.  */
1581         ktime_t cookie_life;
1582 
1583         /* These are the association's initial, max, and min RTO values.
1584          * These values will be initialized by system defaults, but can
1585          * be modified via the SCTP_RTOINFO socket option.
1586          */
1587         unsigned long rto_initial;
1588         unsigned long rto_max;
1589         unsigned long rto_min;
1590 
1591         /* Maximum number of new data packets that can be sent in a burst.  */
1592         int max_burst;
1593 
1594         /* This is the max_retrans value for the association.  This value will
1595          * be initialized initialized from system defaults, but can be
1596          * modified by the SCTP_ASSOCINFO socket option.
1597          */
1598         int max_retrans;
1599 
1600         /* This is the partially failed retrans value for the transport
1601          * and will be initialized from the assocs value.  This can be
1602          * changed using the SCTP_PEER_ADDR_THLDS socket option
1603          */
1604         int pf_retrans;
1605 
1606         /* Maximum number of times the endpoint will retransmit INIT  */
1607         __u16 max_init_attempts;
1608 
1609         /* How many times have we resent an INIT? */
1610         __u16 init_retries;
1611 
1612         /* The largest timeout or RTO value to use in attempting an INIT */
1613         unsigned long max_init_timeo;
1614 
1615         /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1616          * the destination address every heartbeat interval. This value
1617          * will be inherited by all new transports.
1618          */
1619         unsigned long hbinterval;
1620 
1621         /* This is the max_retrans value for new transports in the
1622          * association.
1623          */
1624         __u16 pathmaxrxt;
1625 
1626         /* Flag that path mtu update is pending */
1627         __u8   pmtu_pending;
1628 
1629         /* Association : The smallest PMTU discovered for all of the
1630          * PMTU        : peer's transport addresses.
1631          */
1632         __u32 pathmtu;
1633 
1634         /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1635         __u32 param_flags;
1636 
1637         __u32 sackfreq;
1638         /* SACK delay timeout */
1639         unsigned long sackdelay;
1640 
1641         unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES];
1642         struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1643 
1644         /* Transport to which SHUTDOWN chunk was last sent.  */
1645         struct sctp_transport *shutdown_last_sent_to;
1646 
1647         /* Transport to which INIT chunk was last sent.  */
1648         struct sctp_transport *init_last_sent_to;
1649 
1650         /* How many times have we resent a SHUTDOWN */
1651         int shutdown_retries;
1652 
1653         /* Next TSN    : The next TSN number to be assigned to a new
1654          *             : DATA chunk.  This is sent in the INIT or INIT
1655          *             : ACK chunk to the peer and incremented each
1656          *             : time a DATA chunk is assigned a TSN
1657          *             : (normally just prior to transmit or during
1658          *             : fragmentation).
1659          */
1660         __u32 next_tsn;
1661 
1662         /*
1663          * Last Rcvd   : This is the last TSN received in sequence.  This value
1664          * TSN         : is set initially by taking the peer's Initial TSN,
1665          *             : received in the INIT or INIT ACK chunk, and
1666          *             : subtracting one from it.
1667          *
1668          * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1669          */
1670 
1671         __u32 ctsn_ack_point;
1672 
1673         /* PR-SCTP Advanced.Peer.Ack.Point */
1674         __u32 adv_peer_ack_point;
1675 
1676         /* Highest TSN that is acknowledged by incoming SACKs. */
1677         __u32 highest_sacked;
1678 
1679         /* TSN marking the fast recovery exit point */
1680         __u32 fast_recovery_exit;
1681 
1682         /* Flag to track the current fast recovery state */
1683         __u8 fast_recovery;
1684 
1685         /* The number of unacknowledged data chunks.  Reported through
1686          * the SCTP_STATUS sockopt.
1687          */
1688         __u16 unack_data;
1689 
1690         /* The total number of data chunks that we've had to retransmit
1691          * as the result of a T3 timer expiration
1692          */
1693         __u32 rtx_data_chunks;
1694 
1695         /* This is the association's receive buffer space.  This value is used
1696          * to set a_rwnd field in an INIT or a SACK chunk.
1697          */
1698         __u32 rwnd;
1699 
1700         /* This is the last advertised value of rwnd over a SACK chunk. */
1701         __u32 a_rwnd;
1702 
1703         /* Number of bytes by which the rwnd has slopped.  The rwnd is allowed
1704          * to slop over a maximum of the association's frag_point.
1705          */
1706         __u32 rwnd_over;
1707 
1708         /* Keeps treack of rwnd pressure.  This happens when we have
1709          * a window, but not recevie buffer (i.e small packets).  This one
1710          * is releases slowly (1 PMTU at a time ).
1711          */
1712         __u32 rwnd_press;
1713 
1714         /* This is the sndbuf size in use for the association.
1715          * This corresponds to the sndbuf size for the association,
1716          * as specified in the sk->sndbuf.
1717          */
1718         int sndbuf_used;
1719 
1720         /* This is the amount of memory that this association has allocated
1721          * in the receive path at any given time.
1722          */
1723         atomic_t rmem_alloc;
1724 
1725         /* This is the wait queue head for send requests waiting on
1726          * the association sndbuf space.
1727          */
1728         wait_queue_head_t       wait;
1729 
1730         /* The message size at which SCTP fragmentation will occur. */
1731         __u32 frag_point;
1732         __u32 user_frag;
1733 
1734         /* Counter used to count INIT errors. */
1735         int init_err_counter;
1736 
1737         /* Count the number of INIT cycles (for doubling timeout). */
1738         int init_cycle;
1739 
1740         /* Default send parameters. */
1741         __u16 default_stream;
1742         __u16 default_flags;
1743         __u32 default_ppid;
1744         __u32 default_context;
1745         __u32 default_timetolive;
1746 
1747         /* Default receive parameters */
1748         __u32 default_rcv_context;
1749 
1750         /* Stream arrays */
1751         struct sctp_stream *stream;
1752 
1753         /* All outbound chunks go through this structure.  */
1754         struct sctp_outq outqueue;
1755 
1756         /* A smart pipe that will handle reordering and fragmentation,
1757          * as well as handle passing events up to the ULP.
1758          */
1759         struct sctp_ulpq ulpq;
1760 
1761         /* Last TSN that caused an ECNE Chunk to be sent.  */
1762         __u32 last_ecne_tsn;
1763 
1764         /* Last TSN that caused a CWR Chunk to be sent.  */
1765         __u32 last_cwr_tsn;
1766 
1767         /* How many duplicated TSNs have we seen?  */
1768         int numduptsns;
1769 
1770         /* These are to support
1771          * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1772          *  and Enforcement of Flow and Message Limits"
1773          * <draft-ietf-tsvwg-addip-sctp-02.txt>
1774          * or "ADDIP" for short.
1775          */
1776 
1777 
1778 
1779         /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1780          *
1781          * R1) One and only one ASCONF Chunk MAY be in transit and
1782          * unacknowledged at any one time.  If a sender, after sending
1783          * an ASCONF chunk, decides it needs to transfer another
1784          * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1785          * returns from the previous ASCONF Chunk before sending a
1786          * subsequent ASCONF. Note this restriction binds each side,
1787          * so at any time two ASCONF may be in-transit on any given
1788          * association (one sent from each endpoint).
1789          *
1790          * [This is our one-and-only-one ASCONF in flight.  If we do
1791          * not have an ASCONF in flight, this is NULL.]
1792          */
1793         struct sctp_chunk *addip_last_asconf;
1794 
1795         /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
1796          *
1797          * This is needed to implement itmes E1 - E4 of the updated
1798          * spec.  Here is the justification:
1799          *
1800          * Since the peer may bundle multiple ASCONF chunks toward us,
1801          * we now need the ability to cache multiple ACKs.  The section
1802          * describes in detail how they are cached and cleaned up.
1803          */
1804         struct list_head asconf_ack_list;
1805 
1806         /* These ASCONF chunks are waiting to be sent.
1807          *
1808          * These chunaks can't be pushed to outqueue until receiving
1809          * ASCONF_ACK for the previous ASCONF indicated by
1810          * addip_last_asconf, so as to guarantee that only one ASCONF
1811          * is in flight at any time.
1812          *
1813          * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1814          *
1815          * In defining the ASCONF Chunk transfer procedures, it is
1816          * essential that these transfers MUST NOT cause congestion
1817          * within the network.  To achieve this, we place these
1818          * restrictions on the transfer of ASCONF Chunks:
1819          *
1820          * R1) One and only one ASCONF Chunk MAY be in transit and
1821          * unacknowledged at any one time.  If a sender, after sending
1822          * an ASCONF chunk, decides it needs to transfer another
1823          * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1824          * returns from the previous ASCONF Chunk before sending a
1825          * subsequent ASCONF. Note this restriction binds each side,
1826          * so at any time two ASCONF may be in-transit on any given
1827          * association (one sent from each endpoint).
1828          *
1829          *
1830          * [I really think this is EXACTLY the sort of intelligence
1831          *  which already resides in sctp_outq.  Please move this
1832          *  queue and its supporting logic down there.  --piggy]
1833          */
1834         struct list_head addip_chunk_list;
1835 
1836         /* ADDIP Section 4.1 ASCONF Chunk Procedures
1837          *
1838          * A2) A serial number should be assigned to the Chunk. The
1839          * serial number SHOULD be a monotonically increasing
1840          * number. The serial number SHOULD be initialized at
1841          * the start of the association to the same value as the
1842          * Initial TSN and every time a new ASCONF chunk is created
1843          * it is incremented by one after assigning the serial number
1844          * to the newly created chunk.
1845          *
1846          * ADDIP
1847          * 3.1.1  Address/Stream Configuration Change Chunk (ASCONF)
1848          *
1849          * Serial Number : 32 bits (unsigned integer)
1850          *
1851          * This value represents a Serial Number for the ASCONF
1852          * Chunk. The valid range of Serial Number is from 0 to
1853          * 4294967295 (2^32 - 1).  Serial Numbers wrap back to 0
1854          * after reaching 4294967295.
1855          */
1856         __u32 addip_serial;
1857         int src_out_of_asoc_ok;
1858         union sctp_addr *asconf_addr_del_pending;
1859         struct sctp_transport *new_transport;
1860 
1861         /* SCTP AUTH: list of the endpoint shared keys.  These
1862          * keys are provided out of band by the user applicaton
1863          * and can't change during the lifetime of the association
1864          */
1865         struct list_head endpoint_shared_keys;
1866 
1867         /* SCTP AUTH:
1868          * The current generated assocaition shared key (secret)
1869          */
1870         struct sctp_auth_bytes *asoc_shared_key;
1871 
1872         /* SCTP AUTH: hmac id of the first peer requested algorithm
1873          * that we support.
1874          */
1875         __u16 default_hmac_id;
1876 
1877         __u16 active_key_id;
1878 
1879         __u8 need_ecne:1,       /* Need to send an ECNE Chunk? */
1880              temp:1,            /* Is it a temporary association? */
1881              force_delay:1,
1882              prsctp_enable:1,
1883              reconf_enable:1;
1884 
1885         __u8 strreset_enable;
1886         __u8 strreset_outstanding; /* request param count on the fly */
1887 
1888         __u32 strreset_outseq; /* Update after receiving response */
1889         __u32 strreset_inseq; /* Update after receiving request */
1890 
1891         struct sctp_chunk *strreset_chunk; /* save request chunk */
1892 
1893         struct sctp_priv_assoc_stats stats;
1894 
1895         int sent_cnt_removable;
1896 
1897         __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1];
1898         __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1];
1899 };
1900 
1901 
1902 /* An eyecatcher for determining if we are really looking at an
1903  * association data structure.
1904  */
1905 enum {
1906         SCTP_ASSOC_EYECATCHER = 0xa550c123,
1907 };
1908 
1909 /* Recover the outter association structure. */
1910 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
1911 {
1912         struct sctp_association *asoc;
1913 
1914         asoc = container_of(base, struct sctp_association, base);
1915         return asoc;
1916 }
1917 
1918 /* These are function signatures for manipulating associations.  */
1919 
1920 
1921 struct sctp_association *
1922 sctp_association_new(const struct sctp_endpoint *, const struct sock *,
1923                      sctp_scope_t scope, gfp_t gfp);
1924 void sctp_association_free(struct sctp_association *);
1925 void sctp_association_put(struct sctp_association *);
1926 void sctp_association_hold(struct sctp_association *);
1927 
1928 struct sctp_transport *sctp_assoc_choose_alter_transport(
1929         struct sctp_association *, struct sctp_transport *);
1930 void sctp_assoc_update_retran_path(struct sctp_association *);
1931 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
1932                                           const union sctp_addr *);
1933 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1934                             const union sctp_addr *laddr);
1935 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
1936                                      const union sctp_addr *address,
1937                                      const gfp_t gfp,
1938                                      const int peer_state);
1939 void sctp_assoc_del_peer(struct sctp_association *asoc,
1940                          const union sctp_addr *addr);
1941 void sctp_assoc_rm_peer(struct sctp_association *asoc,
1942                          struct sctp_transport *peer);
1943 void sctp_assoc_control_transport(struct sctp_association *,
1944                                   struct sctp_transport *,
1945                                   sctp_transport_cmd_t, sctp_sn_error_t);
1946 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
1947 struct sctp_transport *sctp_assoc_is_match(struct sctp_association *,
1948                                            struct net *,
1949                                            const union sctp_addr *,
1950                                            const union sctp_addr *);
1951 void sctp_assoc_migrate(struct sctp_association *, struct sock *);
1952 void sctp_assoc_update(struct sctp_association *old,
1953                        struct sctp_association *new);
1954 
1955 __u32 sctp_association_get_next_tsn(struct sctp_association *);
1956 
1957 void sctp_assoc_sync_pmtu(struct sctp_association *asoc);
1958 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int);
1959 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int);
1960 void sctp_assoc_set_primary(struct sctp_association *,
1961                             struct sctp_transport *);
1962 void sctp_assoc_del_nonprimary_peers(struct sctp_association *,
1963                                     struct sctp_transport *);
1964 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *,
1965                                      sctp_scope_t, gfp_t);
1966 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
1967                                          struct sctp_cookie*,
1968                                          gfp_t gfp);
1969 int sctp_assoc_set_id(struct sctp_association *, gfp_t);
1970 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc);
1971 struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
1972                                         const struct sctp_association *asoc,
1973                                         __be32 serial);
1974 void sctp_asconf_queue_teardown(struct sctp_association *asoc);
1975 
1976 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1977                         const union sctp_addr *ss2);
1978 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
1979 
1980 /* A convenience structure to parse out SCTP specific CMSGs. */
1981 typedef struct sctp_cmsgs {
1982         struct sctp_initmsg *init;
1983         struct sctp_sndrcvinfo *srinfo;
1984         struct sctp_sndinfo *sinfo;
1985 } sctp_cmsgs_t;
1986 
1987 /* Structure for tracking memory objects */
1988 typedef struct {
1989         char *label;
1990         atomic_t *counter;
1991 } sctp_dbg_objcnt_entry_t;
1992 
1993 #endif /* __sctp_structs_h__ */
1994 

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