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 */
  67union sctp_addr {
  68        struct sockaddr_in v4;
  69        struct sockaddr_in6 v6;
  70        struct sockaddr sa;
  71};
  72
  73/* Forward declarations for data structures. */
  74struct sctp_globals;
  75struct sctp_endpoint;
  76struct sctp_association;
  77struct sctp_transport;
  78struct sctp_packet;
  79struct sctp_chunk;
  80struct sctp_inq;
  81struct sctp_outq;
  82struct sctp_bind_addr;
  83struct sctp_ulpq;
  84struct sctp_ep_common;
  85struct sctp_ssnmap;
  86struct crypto_shash;
  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
  95struct 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
 103struct sctp_bind_hashbucket {
 104        spinlock_t      lock;
 105        struct hlist_head       chain;
 106};
 107
 108/* Used for hashing all associations.  */
 109struct sctp_hashbucket {
 110        rwlock_t        lock;
 111        struct hlist_head       chain;
 112} __attribute__((__aligned__(8)));
 113
 114
 115/* The SCTP globals structure. */
 116extern 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 rhashtable 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. */
 153typedef 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. */
 160struct 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
 235static inline struct sctp_sock *sctp_sk(const struct sock *sk)
 236{
 237       return (struct sctp_sock *)sk;
 238}
 239
 240static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
 241{
 242       return (struct sock *)sp;
 243}
 244
 245#if IS_ENABLED(CONFIG_IPV6)
 246struct 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
 262struct 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. */
 329struct 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 */
 339union 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 */
 348union 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 */
 373typedef 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} __packed sctp_sender_hb_info_t;
 379
 380/*
 381 *  RFC 2960 1.3.2 Sequenced Delivery within Streams
 382 *
 383 *  The term "stream" is used in SCTP to refer to a sequence of user
 384 *  messages that are to be delivered to the upper-layer protocol in
 385 *  order with respect to other messages within the same stream.  This is
 386 *  in contrast to its usage in TCP, where it refers to a sequence of
 387 *  bytes (in this document a byte is assumed to be eight bits).
 388 *  ...
 389 *
 390 *  This is the structure we use to track both our outbound and inbound
 391 *  SSN, or Stream Sequence Numbers.
 392 */
 393
 394struct sctp_stream {
 395        __u16 *ssn;
 396        unsigned int len;
 397};
 398
 399struct sctp_ssnmap {
 400        struct sctp_stream in;
 401        struct sctp_stream out;
 402};
 403
 404struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out,
 405                                    gfp_t gfp);
 406void sctp_ssnmap_free(struct sctp_ssnmap *map);
 407void sctp_ssnmap_clear(struct sctp_ssnmap *map);
 408
 409/* What is the current SSN number for this stream? */
 410static inline __u16 sctp_ssn_peek(struct sctp_stream *stream, __u16 id)
 411{
 412        return stream->ssn[id];
 413}
 414
 415/* Return the next SSN number for this stream.  */
 416static inline __u16 sctp_ssn_next(struct sctp_stream *stream, __u16 id)
 417{
 418        return stream->ssn[id]++;
 419}
 420
 421/* Skip over this ssn and all below. */
 422static inline void sctp_ssn_skip(struct sctp_stream *stream, __u16 id, 
 423                                 __u16 ssn)
 424{
 425        stream->ssn[id] = ssn+1;
 426}
 427              
 428/*
 429 * Pointers to address related SCTP functions.
 430 * (i.e. things that depend on the address family.)
 431 */
 432struct sctp_af {
 433        int             (*sctp_xmit)    (struct sk_buff *skb,
 434                                         struct sctp_transport *);
 435        int             (*setsockopt)   (struct sock *sk,
 436                                         int level,
 437                                         int optname,
 438                                         char __user *optval,
 439                                         unsigned int optlen);
 440        int             (*getsockopt)   (struct sock *sk,
 441                                         int level,
 442                                         int optname,
 443                                         char __user *optval,
 444                                         int __user *optlen);
 445        int             (*compat_setsockopt)    (struct sock *sk,
 446                                         int level,
 447                                         int optname,
 448                                         char __user *optval,
 449                                         unsigned int optlen);
 450        int             (*compat_getsockopt)    (struct sock *sk,
 451                                         int level,
 452                                         int optname,
 453                                         char __user *optval,
 454                                         int __user *optlen);
 455        void            (*get_dst)      (struct sctp_transport *t,
 456                                         union sctp_addr *saddr,
 457                                         struct flowi *fl,
 458                                         struct sock *sk);
 459        void            (*get_saddr)    (struct sctp_sock *sk,
 460                                         struct sctp_transport *t,
 461                                         struct flowi *fl);
 462        void            (*copy_addrlist) (struct list_head *,
 463                                          struct net_device *);
 464        int             (*cmp_addr)     (const union sctp_addr *addr1,
 465                                         const union sctp_addr *addr2);
 466        void            (*addr_copy)    (union sctp_addr *dst,
 467                                         union sctp_addr *src);
 468        void            (*from_skb)     (union sctp_addr *,
 469                                         struct sk_buff *skb,
 470                                         int saddr);
 471        void            (*from_sk)      (union sctp_addr *,
 472                                         struct sock *sk);
 473        void            (*from_addr_param) (union sctp_addr *,
 474                                            union sctp_addr_param *,
 475                                            __be16 port, int iif);
 476        int             (*to_addr_param) (const union sctp_addr *,
 477                                          union sctp_addr_param *); 
 478        int             (*addr_valid)   (union sctp_addr *,
 479                                         struct sctp_sock *,
 480                                         const struct sk_buff *);
 481        sctp_scope_t    (*scope) (union sctp_addr *);
 482        void            (*inaddr_any)   (union sctp_addr *, __be16);
 483        int             (*is_any)       (const union sctp_addr *);
 484        int             (*available)    (union sctp_addr *,
 485                                         struct sctp_sock *);
 486        int             (*skb_iif)      (const struct sk_buff *sk);
 487        int             (*is_ce)        (const struct sk_buff *sk);
 488        void            (*seq_dump_addr)(struct seq_file *seq,
 489                                         union sctp_addr *addr);
 490        void            (*ecn_capable)(struct sock *sk);
 491        __u16           net_header_len;
 492        int             sockaddr_len;
 493        sa_family_t     sa_family;
 494        struct list_head list;
 495};
 496
 497struct sctp_af *sctp_get_af_specific(sa_family_t);
 498int sctp_register_af(struct sctp_af *);
 499
 500/* Protocol family functions. */
 501struct sctp_pf {
 502        void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
 503        void (*skb_msgname)  (struct sk_buff *, char *, int *);
 504        int  (*af_supported) (sa_family_t, struct sctp_sock *);
 505        int  (*cmp_addr) (const union sctp_addr *,
 506                          const union sctp_addr *,
 507                          struct sctp_sock *);
 508        int  (*bind_verify) (struct sctp_sock *, union sctp_addr *);
 509        int  (*send_verify) (struct sctp_sock *, union sctp_addr *);
 510        int  (*supported_addrs)(const struct sctp_sock *, __be16 *);
 511        struct sock *(*create_accept_sk) (struct sock *sk,
 512                                          struct sctp_association *asoc);
 513        int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr);
 514        void (*to_sk_saddr)(union sctp_addr *, struct sock *sk);
 515        void (*to_sk_daddr)(union sctp_addr *, struct sock *sk);
 516        struct sctp_af *af;
 517};
 518
 519
 520/* Structure to track chunk fragments that have been acked, but peer
 521 * fragments of the same message have not.
 522 */
 523struct sctp_datamsg {
 524        /* Chunks waiting to be submitted to lower layer. */
 525        struct list_head chunks;
 526        /* Reference counting. */
 527        atomic_t refcnt;
 528        /* When is this message no longer interesting to the peer? */
 529        unsigned long expires_at;
 530        /* Did the messenge fail to send? */
 531        int send_error;
 532        u8 send_failed:1,
 533           can_abandon:1,   /* can chunks from this message can be abandoned. */
 534           can_delay;       /* should this message be Nagle delayed */
 535};
 536
 537struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
 538                                            struct sctp_sndrcvinfo *,
 539                                            struct iov_iter *);
 540void sctp_datamsg_put(struct sctp_datamsg *);
 541void sctp_chunk_fail(struct sctp_chunk *, int error);
 542int sctp_chunk_abandoned(struct sctp_chunk *);
 543
 544/* RFC2960 1.4 Key Terms
 545 *
 546 * o Chunk: A unit of information within an SCTP packet, consisting of
 547 * a chunk header and chunk-specific content.
 548 *
 549 * As a matter of convenience, we remember the SCTP common header for
 550 * each chunk as well as a few other header pointers...
 551 */
 552struct sctp_chunk {
 553        struct list_head list;
 554
 555        atomic_t refcnt;
 556
 557        /* How many times this chunk have been sent, for prsctp RTX policy */
 558        int sent_count;
 559
 560        /* This is our link to the per-transport transmitted list.  */
 561        struct list_head transmitted_list;
 562
 563        /* This field is used by chunks that hold fragmented data.
 564         * For the first fragment this is the list that holds the rest of
 565         * fragments. For the remaining fragments, this is the link to the
 566         * frag_list maintained in the first fragment.
 567         */
 568        struct list_head frag_list;
 569
 570        /* This points to the sk_buff containing the actual data.  */
 571        struct sk_buff *skb;
 572
 573        /* In case of GSO packets, this will store the head one */
 574        struct sk_buff *head_skb;
 575
 576        /* These are the SCTP headers by reverse order in a packet.
 577         * Note that some of these may happen more than once.  In that
 578         * case, we point at the "current" one, whatever that means
 579         * for that level of header.
 580         */
 581
 582        /* We point this at the FIRST TLV parameter to chunk_hdr.  */
 583        union sctp_params param_hdr;
 584        union {
 585                __u8 *v;
 586                struct sctp_datahdr *data_hdr;
 587                struct sctp_inithdr *init_hdr;
 588                struct sctp_sackhdr *sack_hdr;
 589                struct sctp_heartbeathdr *hb_hdr;
 590                struct sctp_sender_hb_info *hbs_hdr;
 591                struct sctp_shutdownhdr *shutdown_hdr;
 592                struct sctp_signed_cookie *cookie_hdr;
 593                struct sctp_ecnehdr *ecne_hdr;
 594                struct sctp_cwrhdr *ecn_cwr_hdr;
 595                struct sctp_errhdr *err_hdr;
 596                struct sctp_addiphdr *addip_hdr;
 597                struct sctp_fwdtsn_hdr *fwdtsn_hdr;
 598                struct sctp_authhdr *auth_hdr;
 599        } subh;
 600
 601        __u8 *chunk_end;
 602
 603        struct sctp_chunkhdr *chunk_hdr;
 604        struct sctphdr *sctp_hdr;
 605
 606        /* This needs to be recoverable for SCTP_SEND_FAILED events. */
 607        struct sctp_sndrcvinfo sinfo;
 608
 609        /* Which association does this belong to?  */
 610        struct sctp_association *asoc;
 611
 612        /* What endpoint received this chunk? */
 613        struct sctp_ep_common *rcvr;
 614
 615        /* We fill this in if we are calculating RTT. */
 616        unsigned long sent_at;
 617
 618        /* What is the origin IP address for this chunk?  */
 619        union sctp_addr source;
 620        /* Destination address for this chunk. */
 621        union sctp_addr dest;
 622
 623        /* For outbound message, track all fragments for SEND_FAILED. */
 624        struct sctp_datamsg *msg;
 625
 626        /* For an inbound chunk, this tells us where it came from.
 627         * For an outbound chunk, it tells us where we'd like it to
 628         * go.  It is NULL if we have no preference.
 629         */
 630        struct sctp_transport *transport;
 631
 632        /* SCTP-AUTH:  For the special case inbound processing of COOKIE-ECHO
 633         * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
 634         * spec violates the principle premis that all chunks are processed
 635         * in order.
 636         */
 637        struct sk_buff *auth_chunk;
 638
 639#define SCTP_CAN_FRTX 0x0
 640#define SCTP_NEED_FRTX 0x1
 641#define SCTP_DONT_FRTX 0x2
 642        __u16   rtt_in_progress:1,      /* This chunk used for RTT calc? */
 643                resent:1,               /* Has this chunk ever been resent. */
 644                has_tsn:1,              /* Does this chunk have a TSN yet? */
 645                has_ssn:1,              /* Does this chunk have a SSN yet? */
 646                singleton:1,            /* Only chunk in the packet? */
 647                end_of_packet:1,        /* Last chunk in the packet? */
 648                ecn_ce_done:1,          /* Have we processed the ECN CE bit? */
 649                pdiscard:1,             /* Discard the whole packet now? */
 650                tsn_gap_acked:1,        /* Is this chunk acked by a GAP ACK? */
 651                data_accepted:1,        /* At least 1 chunk accepted */
 652                auth:1,                 /* IN: was auth'ed | OUT: needs auth */
 653                has_asconf:1,           /* IN: have seen an asconf before */
 654                tsn_missing_report:2,   /* Data chunk missing counter. */
 655                fast_retransmit:2;      /* Is this chunk fast retransmitted? */
 656};
 657
 658void sctp_chunk_hold(struct sctp_chunk *);
 659void sctp_chunk_put(struct sctp_chunk *);
 660int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len,
 661                          struct iov_iter *from);
 662void sctp_chunk_free(struct sctp_chunk *);
 663void  *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
 664struct sctp_chunk *sctp_chunkify(struct sk_buff *,
 665                                 const struct sctp_association *,
 666                                 struct sock *, gfp_t gfp);
 667void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
 668                     union sctp_addr *);
 669const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
 670
 671enum {
 672        SCTP_ADDR_NEW,          /* new address added to assoc/ep */
 673        SCTP_ADDR_SRC,          /* address can be used as source */
 674        SCTP_ADDR_DEL,          /* address about to be deleted */
 675};
 676
 677/* This is a structure for holding either an IPv6 or an IPv4 address.  */
 678struct sctp_sockaddr_entry {
 679        struct list_head list;
 680        struct rcu_head rcu;
 681        union sctp_addr a;
 682        __u8 state;
 683        __u8 valid;
 684};
 685
 686#define SCTP_ADDRESS_TICK_DELAY 500
 687
 688typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *);
 689
 690/* This structure holds lists of chunks as we are assembling for
 691 * transmission.
 692 */
 693struct sctp_packet {
 694        /* These are the SCTP header values (host order) for the packet. */
 695        __u16 source_port;
 696        __u16 destination_port;
 697        __u32 vtag;
 698
 699        /* This contains the payload chunks.  */
 700        struct list_head chunk_list;
 701
 702        /* This is the overhead of the sctp and ip headers. */
 703        size_t overhead;
 704        /* This is the total size of all chunks INCLUDING padding.  */
 705        size_t size;
 706        /* This is the maximum size this packet may have */
 707        size_t max_size;
 708
 709        /* The packet is destined for this transport address.
 710         * The function we finally use to pass down to the next lower
 711         * layer lives in the transport structure.
 712         */
 713        struct sctp_transport *transport;
 714
 715        /* pointer to the auth chunk for this packet */
 716        struct sctp_chunk *auth;
 717
 718        u8  has_cookie_echo:1,  /* This packet contains a COOKIE-ECHO chunk. */
 719            has_sack:1,         /* This packet contains a SACK chunk. */
 720            has_auth:1,         /* This packet contains an AUTH chunk */
 721            has_data:1,         /* This packet contains at least 1 DATA chunk */
 722            ipfragok:1;         /* So let ip fragment this packet */
 723};
 724
 725struct sctp_packet *sctp_packet_init(struct sctp_packet *,
 726                                     struct sctp_transport *,
 727                                     __u16 sport, __u16 dport);
 728struct sctp_packet *sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
 729sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *,
 730                                       struct sctp_chunk *, int, gfp_t);
 731sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *,
 732                                     struct sctp_chunk *);
 733int sctp_packet_transmit(struct sctp_packet *, gfp_t);
 734void sctp_packet_free(struct sctp_packet *);
 735
 736static inline int sctp_packet_empty(struct sctp_packet *packet)
 737{
 738        return packet->size == packet->overhead;
 739}
 740
 741/* This represents a remote transport address.
 742 * For local transport addresses, we just use union sctp_addr.
 743 *
 744 * RFC2960 Section 1.4 Key Terms
 745 *
 746 *   o  Transport address:  A Transport Address is traditionally defined
 747 *      by Network Layer address, Transport Layer protocol and Transport
 748 *      Layer port number.  In the case of SCTP running over IP, a
 749 *      transport address is defined by the combination of an IP address
 750 *      and an SCTP port number (where SCTP is the Transport protocol).
 751 *
 752 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
 753 *
 754 *   o  The sender keeps a separate congestion control parameter set for
 755 *      each of the destination addresses it can send to (not each
 756 *      source-destination pair but for each destination).  The parameters
 757 *      should decay if the address is not used for a long enough time
 758 *      period.
 759 *
 760 */
 761struct sctp_transport {
 762        /* A list of transports. */
 763        struct list_head transports;
 764        struct rhash_head node;
 765
 766        /* Reference counting. */
 767        atomic_t refcnt;
 768                /* RTO-Pending : A flag used to track if one of the DATA
 769                 *              chunks sent to this address is currently being
 770                 *              used to compute a RTT. If this flag is 0,
 771                 *              the next DATA chunk sent to this destination
 772                 *              should be used to compute a RTT and this flag
 773                 *              should be set. Every time the RTT
 774                 *              calculation completes (i.e. the DATA chunk
 775                 *              is SACK'd) clear this flag.
 776                 */
 777        __u32   rto_pending:1,
 778
 779                /*
 780                 * hb_sent : a flag that signals that we have a pending
 781                 * heartbeat.
 782                 */
 783                hb_sent:1,
 784
 785                /* Is the Path MTU update pending on this tranport */
 786                pmtu_pending:1,
 787
 788                /* Has this transport moved the ctsn since we last sacked */
 789                sack_generation:1;
 790        u32 dst_cookie;
 791
 792        struct flowi fl;
 793
 794        /* This is the peer's IP address and port. */
 795        union sctp_addr ipaddr;
 796
 797        /* These are the functions we call to handle LLP stuff.  */
 798        struct sctp_af *af_specific;
 799
 800        /* Which association do we belong to?  */
 801        struct sctp_association *asoc;
 802
 803        /* RFC2960
 804         *
 805         * 12.3 Per Transport Address Data
 806         *
 807         * For each destination transport address in the peer's
 808         * address list derived from the INIT or INIT ACK chunk, a
 809         * number of data elements needs to be maintained including:
 810         */
 811        /* RTO         : The current retransmission timeout value.  */
 812        unsigned long rto;
 813
 814        __u32 rtt;              /* This is the most recent RTT.  */
 815
 816        /* RTTVAR      : The current RTT variation.  */
 817        __u32 rttvar;
 818
 819        /* SRTT        : The current smoothed round trip time.  */
 820        __u32 srtt;
 821
 822        /*
 823         * These are the congestion stats.
 824         */
 825        /* cwnd        : The current congestion window.  */
 826        __u32 cwnd;               /* This is the actual cwnd.  */
 827
 828        /* ssthresh    : The current slow start threshold value.  */
 829        __u32 ssthresh;
 830
 831        /* partial     : The tracking method for increase of cwnd when in
 832         * bytes acked : congestion avoidance mode (see Section 6.2.2)
 833         */
 834        __u32 partial_bytes_acked;
 835
 836        /* Data that has been sent, but not acknowledged. */
 837        __u32 flight_size;
 838
 839        __u32 burst_limited;    /* Holds old cwnd when max.burst is applied */
 840
 841        /* Destination */
 842        struct dst_entry *dst;
 843        /* Source address. */
 844        union sctp_addr saddr;
 845
 846        /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
 847         * the destination address every heartbeat interval.
 848         */
 849        unsigned long hbinterval;
 850
 851        /* SACK delay timeout */
 852        unsigned long sackdelay;
 853        __u32 sackfreq;
 854
 855        /* When was the last time that we heard from this transport? We use
 856         * this to pick new active and retran paths.
 857         */
 858        ktime_t last_time_heard;
 859
 860        /* When was the last time that we sent a chunk using this
 861         * transport? We use this to check for idle transports
 862         */
 863        unsigned long last_time_sent;
 864
 865        /* Last time(in jiffies) when cwnd is reduced due to the congestion
 866         * indication based on ECNE chunk.
 867         */
 868        unsigned long last_time_ecne_reduced;
 869
 870        /* This is the max_retrans value for the transport and will
 871         * be initialized from the assocs value.  This can be changed
 872         * using the SCTP_SET_PEER_ADDR_PARAMS socket option.
 873         */
 874        __u16 pathmaxrxt;
 875
 876        /* This is the partially failed retrans value for the transport
 877         * and will be initialized from the assocs value.  This can be changed
 878         * using the SCTP_PEER_ADDR_THLDS socket option
 879         */
 880        int pf_retrans;
 881        /* PMTU       : The current known path MTU.  */
 882        __u32 pathmtu;
 883
 884        /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
 885        __u32 param_flags;
 886
 887        /* The number of times INIT has been sent on this transport. */
 888        int init_sent_count;
 889
 890        /* state       : The current state of this destination,
 891         *             : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
 892         */
 893        int state;
 894
 895        /* These are the error stats for this destination.  */
 896
 897        /* Error count : The current error count for this destination.  */
 898        unsigned short error_count;
 899
 900        /* Per         : A timer used by each destination.
 901         * Destination :
 902         * Timer       :
 903         *
 904         * [Everywhere else in the text this is called T3-rtx. -ed]
 905         */
 906        struct timer_list T3_rtx_timer;
 907
 908        /* Heartbeat timer is per destination. */
 909        struct timer_list hb_timer;
 910
 911        /* Timer to handle ICMP proto unreachable envets */
 912        struct timer_list proto_unreach_timer;
 913
 914        /* Since we're using per-destination retransmission timers
 915         * (see above), we're also using per-destination "transmitted"
 916         * queues.  This probably ought to be a private struct
 917         * accessible only within the outqueue, but it's not, yet.
 918         */
 919        struct list_head transmitted;
 920
 921        /* We build bundle-able packets for this transport here.  */
 922        struct sctp_packet packet;
 923
 924        /* This is the list of transports that have chunks to send.  */
 925        struct list_head send_ready;
 926
 927        /* State information saved for SFR_CACC algorithm. The key
 928         * idea in SFR_CACC is to maintain state at the sender on a
 929         * per-destination basis when a changeover happens.
 930         *      char changeover_active;
 931         *      char cycling_changeover;
 932         *      __u32 next_tsn_at_change;
 933         *      char cacc_saw_newack;
 934         */
 935        struct {
 936                /* An unsigned integer, which stores the next TSN to be
 937                 * used by the sender, at the moment of changeover.
 938                 */
 939                __u32 next_tsn_at_change;
 940
 941                /* A flag which indicates the occurrence of a changeover */
 942                char changeover_active;
 943
 944                /* A flag which indicates whether the change of primary is
 945                 * the first switch to this destination address during an
 946                 * active switch.
 947                 */
 948                char cycling_changeover;
 949
 950                /* A temporary flag, which is used during the processing of
 951                 * a SACK to estimate the causative TSN(s)'s group.
 952                 */
 953                char cacc_saw_newack;
 954        } cacc;
 955
 956        /* 64-bit random number sent with heartbeat. */
 957        __u64 hb_nonce;
 958
 959        struct rcu_head rcu;
 960};
 961
 962struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *,
 963                                          gfp_t);
 964void sctp_transport_set_owner(struct sctp_transport *,
 965                              struct sctp_association *);
 966void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
 967                          struct sctp_sock *);
 968void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk);
 969void sctp_transport_free(struct sctp_transport *);
 970void sctp_transport_reset_t3_rtx(struct sctp_transport *);
 971void sctp_transport_reset_hb_timer(struct sctp_transport *);
 972int sctp_transport_hold(struct sctp_transport *);
 973void sctp_transport_put(struct sctp_transport *);
 974void sctp_transport_update_rto(struct sctp_transport *, __u32);
 975void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
 976void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t);
 977void sctp_transport_burst_limited(struct sctp_transport *);
 978void sctp_transport_burst_reset(struct sctp_transport *);
 979unsigned long sctp_transport_timeout(struct sctp_transport *);
 980void sctp_transport_reset(struct sctp_transport *);
 981void sctp_transport_update_pmtu(struct sock *, struct sctp_transport *, u32);
 982void sctp_transport_immediate_rtx(struct sctp_transport *);
 983
 984
 985/* This is the structure we use to queue packets as they come into
 986 * SCTP.  We write packets to it and read chunks from it.
 987 */
 988struct sctp_inq {
 989        /* This is actually a queue of sctp_chunk each
 990         * containing a partially decoded packet.
 991         */
 992        struct list_head in_chunk_list;
 993        /* This is the packet which is currently off the in queue and is
 994         * being worked on through the inbound chunk processing.
 995         */
 996        struct sctp_chunk *in_progress;
 997
 998        /* This is the delayed task to finish delivering inbound
 999         * messages.
1000         */
1001        struct work_struct immediate;
1002};
1003
1004void sctp_inq_init(struct sctp_inq *);
1005void sctp_inq_free(struct sctp_inq *);
1006void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
1007struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
1008struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *);
1009void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t);
1010
1011/* This is the structure we use to hold outbound chunks.  You push
1012 * chunks in and they automatically pop out the other end as bundled
1013 * packets (it calls (*output_handler)()).
1014 *
1015 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1016 * and 8.2 of the v13 draft.
1017 *
1018 * It handles retransmissions.  The connection to the timeout portion
1019 * of the state machine is through sctp_..._timeout() and timeout_handler.
1020 *
1021 * If you feed it SACKs, it will eat them.
1022 *
1023 * If you give it big chunks, it will fragment them.
1024 *
1025 * It assigns TSN's to data chunks.  This happens at the last possible
1026 * instant before transmission.
1027 *
1028 * When free()'d, it empties itself out via output_handler().
1029 */
1030struct sctp_outq {
1031        struct sctp_association *asoc;
1032
1033        /* Data pending that has never been transmitted.  */
1034        struct list_head out_chunk_list;
1035
1036        unsigned int out_qlen;  /* Total length of queued data chunks. */
1037
1038        /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1039        unsigned int error;
1040
1041        /* These are control chunks we want to send.  */
1042        struct list_head control_chunk_list;
1043
1044        /* These are chunks that have been sacked but are above the
1045         * CTSN, or cumulative tsn ack point.
1046         */
1047        struct list_head sacked;
1048
1049        /* Put chunks on this list to schedule them for
1050         * retransmission.
1051         */
1052        struct list_head retransmit;
1053
1054        /* Put chunks on this list to save them for FWD TSN processing as
1055         * they were abandoned.
1056         */
1057        struct list_head abandoned;
1058
1059        /* How many unackd bytes do we have in-flight?  */
1060        __u32 outstanding_bytes;
1061
1062        /* Are we doing fast-rtx on this queue */
1063        char fast_rtx;
1064
1065        /* Corked? */
1066        char cork;
1067};
1068
1069void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1070void sctp_outq_teardown(struct sctp_outq *);
1071void sctp_outq_free(struct sctp_outq*);
1072int sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t);
1073int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *);
1074int sctp_outq_is_empty(const struct sctp_outq *);
1075void sctp_outq_restart(struct sctp_outq *);
1076
1077void sctp_retransmit(struct sctp_outq *, struct sctp_transport *,
1078                     sctp_retransmit_reason_t);
1079void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1080int sctp_outq_uncork(struct sctp_outq *, gfp_t gfp);
1081void sctp_prsctp_prune(struct sctp_association *asoc,
1082                       struct sctp_sndrcvinfo *sinfo, int msg_len);
1083/* Uncork and flush an outqueue.  */
1084static inline void sctp_outq_cork(struct sctp_outq *q)
1085{
1086        q->cork = 1;
1087}
1088
1089/* SCTP skb control block.
1090 * sctp_input_cb is currently used on rx and sock rx queue
1091 */
1092struct sctp_input_cb {
1093        union {
1094                struct inet_skb_parm    h4;
1095#if IS_ENABLED(CONFIG_IPV6)
1096                struct inet6_skb_parm   h6;
1097#endif
1098        } header;
1099        struct sctp_chunk *chunk;
1100        struct sctp_af *af;
1101};
1102#define SCTP_INPUT_CB(__skb)    ((struct sctp_input_cb *)&((__skb)->cb[0]))
1103
1104static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb)
1105{
1106        const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk;
1107
1108        return chunk->head_skb ? : skb;
1109}
1110
1111/* These bind address data fields common between endpoints and associations */
1112struct sctp_bind_addr {
1113
1114        /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1115         *
1116         * SCTP Port:   The local SCTP port number the endpoint is
1117         *              bound to.
1118         */
1119        __u16 port;
1120
1121        /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1122         *
1123         * Address List: The list of IP addresses that this instance
1124         *      has bound.  This information is passed to one's
1125         *      peer(s) in INIT and INIT ACK chunks.
1126         */
1127        struct list_head address_list;
1128};
1129
1130void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1131void sctp_bind_addr_free(struct sctp_bind_addr *);
1132int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest,
1133                        const struct sctp_bind_addr *src,
1134                        sctp_scope_t scope, gfp_t gfp,
1135                        int flags);
1136int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
1137                        const struct sctp_bind_addr *src,
1138                        gfp_t gfp);
1139int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1140                       int new_size, __u8 addr_state, gfp_t gfp);
1141int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1142int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1143                         struct sctp_sock *);
1144int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *,
1145                         struct sctp_sock *, struct sctp_sock *);
1146int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
1147                         const union sctp_addr *addr);
1148union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr   *bp,
1149                                        const union sctp_addr   *addrs,
1150                                        int                     addrcnt,
1151                                        struct sctp_sock        *opt);
1152union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1153                                         int *addrs_len,
1154                                         gfp_t gfp);
1155int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1156                           __u16 port, gfp_t gfp);
1157
1158sctp_scope_t sctp_scope(const union sctp_addr *);
1159int sctp_in_scope(struct net *net, const union sctp_addr *addr, const sctp_scope_t scope);
1160int sctp_is_any(struct sock *sk, const union sctp_addr *addr);
1161int sctp_is_ep_boundall(struct sock *sk);
1162
1163
1164/* What type of endpoint?  */
1165typedef enum {
1166        SCTP_EP_TYPE_SOCKET,
1167        SCTP_EP_TYPE_ASSOCIATION,
1168} sctp_endpoint_type_t;
1169
1170/*
1171 * A common base class to bridge the implmentation view of a
1172 * socket (usually listening) endpoint versus an association's
1173 * local endpoint.
1174 * This common structure is useful for several purposes:
1175 *   1) Common interface for lookup routines.
1176 *      a) Subfunctions work for either endpoint or association
1177 *      b) Single interface to lookup allows hiding the lookup lock rather
1178 *         than acquiring it externally.
1179 *   2) Common interface for the inbound chunk handling/state machine.
1180 *   3) Common object handling routines for reference counting, etc.
1181 *   4) Disentangle association lookup from endpoint lookup, where we
1182 *      do not have to find our endpoint to find our association.
1183 *
1184 */
1185
1186struct sctp_ep_common {
1187        /* Fields to help us manage our entries in the hash tables. */
1188        struct hlist_node node;
1189        int hashent;
1190
1191        /* Runtime type information.  What kind of endpoint is this? */
1192        sctp_endpoint_type_t type;
1193
1194        /* Some fields to help us manage this object.
1195         *   refcnt   - Reference count access to this object.
1196         *   dead     - Do not attempt to use this object.
1197         */
1198        atomic_t    refcnt;
1199        bool        dead;
1200
1201        /* What socket does this endpoint belong to?  */
1202        struct sock *sk;
1203
1204        /* This is where we receive inbound chunks.  */
1205        struct sctp_inq   inqueue;
1206
1207        /* This substructure includes the defining parameters of the
1208         * endpoint:
1209         * bind_addr.port is our shared port number.
1210         * bind_addr.address_list is our set of local IP addresses.
1211         */
1212        struct sctp_bind_addr bind_addr;
1213};
1214
1215
1216/* RFC Section 1.4 Key Terms
1217 *
1218 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1219 *   multi-homed host, an SCTP endpoint is represented to its peers as a
1220 *   combination of a set of eligible destination transport addresses to
1221 *   which SCTP packets can be sent and a set of eligible source
1222 *   transport addresses from which SCTP packets can be received.
1223 *   All transport addresses used by an SCTP endpoint must use the
1224 *   same port number, but can use multiple IP addresses. A transport
1225 *   address used by an SCTP endpoint must not be used by another
1226 *   SCTP endpoint. In other words, a transport address is unique
1227 *   to an SCTP endpoint.
1228 *
1229 * From an implementation perspective, each socket has one of these.
1230 * A TCP-style socket will have exactly one association on one of
1231 * these.  An UDP-style socket will have multiple associations hanging
1232 * off one of these.
1233 */
1234
1235struct sctp_endpoint {
1236        /* Common substructure for endpoint and association. */
1237        struct sctp_ep_common base;
1238
1239        /* Associations: A list of current associations and mappings
1240         *            to the data consumers for each association. This
1241         *            may be in the form of a hash table or other
1242         *            implementation dependent structure. The data
1243         *            consumers may be process identification
1244         *            information such as file descriptors, named pipe
1245         *            pointer, or table pointers dependent on how SCTP
1246         *            is implemented.
1247         */
1248        /* This is really a list of struct sctp_association entries. */
1249        struct list_head asocs;
1250
1251        /* Secret Key: A secret key used by this endpoint to compute
1252         *            the MAC.  This SHOULD be a cryptographic quality
1253         *            random number with a sufficient length.
1254         *            Discussion in [RFC1750] can be helpful in
1255         *            selection of the key.
1256         */
1257        __u8 secret_key[SCTP_SECRET_SIZE];
1258
1259        /* digest:  This is a digest of the sctp cookie.  This field is
1260         *          only used on the receive path when we try to validate
1261         *          that the cookie has not been tampered with.  We put
1262         *          this here so we pre-allocate this once and can re-use
1263         *          on every receive.
1264         */
1265        __u8 *digest;
1266 
1267        /* sendbuf acct. policy.        */
1268        __u32 sndbuf_policy;
1269
1270        /* rcvbuf acct. policy. */
1271        __u32 rcvbuf_policy;
1272
1273        /* SCTP AUTH: array of the HMACs that will be allocated
1274         * we need this per association so that we don't serialize
1275         */
1276        struct crypto_shash **auth_hmacs;
1277
1278        /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1279         struct sctp_hmac_algo_param *auth_hmacs_list;
1280
1281        /* SCTP-AUTH: chunks to authenticate encoded into parameter */
1282        struct sctp_chunks_param *auth_chunk_list;
1283
1284        /* SCTP-AUTH: endpoint shared keys */
1285        struct list_head endpoint_shared_keys;
1286        __u16 active_key_id;
1287        __u8  auth_enable:1,
1288              prsctp_enable:1;
1289};
1290
1291/* Recover the outter endpoint structure. */
1292static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1293{
1294        struct sctp_endpoint *ep;
1295
1296        ep = container_of(base, struct sctp_endpoint, base);
1297        return ep;
1298}
1299
1300/* These are function signatures for manipulating endpoints.  */
1301struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1302void sctp_endpoint_free(struct sctp_endpoint *);
1303void sctp_endpoint_put(struct sctp_endpoint *);
1304void sctp_endpoint_hold(struct sctp_endpoint *);
1305void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1306struct sctp_association *sctp_endpoint_lookup_assoc(
1307        const struct sctp_endpoint *ep,
1308        const union sctp_addr *paddr,
1309        struct sctp_transport **);
1310int sctp_endpoint_is_peeled_off(struct sctp_endpoint *,
1311                                const union sctp_addr *);
1312struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1313                                        struct net *, const union sctp_addr *);
1314int sctp_has_association(struct net *net, const union sctp_addr *laddr,
1315                         const union sctp_addr *paddr);
1316
1317int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep,
1318                     const struct sctp_association *asoc,
1319                     sctp_cid_t, sctp_init_chunk_t *peer_init,
1320                     struct sctp_chunk *chunk, struct sctp_chunk **err_chunk);
1321int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk,
1322                      const union sctp_addr *peer,
1323                      sctp_init_chunk_t *init, gfp_t gfp);
1324__u32 sctp_generate_tag(const struct sctp_endpoint *);
1325__u32 sctp_generate_tsn(const struct sctp_endpoint *);
1326
1327struct sctp_inithdr_host {
1328        __u32 init_tag;
1329        __u32 a_rwnd;
1330        __u16 num_outbound_streams;
1331        __u16 num_inbound_streams;
1332        __u32 initial_tsn;
1333};
1334
1335/* SCTP_GET_ASSOC_STATS counters */
1336struct sctp_priv_assoc_stats {
1337        /* Maximum observed rto in the association during subsequent
1338         * observations. Value is set to 0 if no RTO measurement took place
1339         * The transport where the max_rto was observed is returned in
1340         * obs_rto_ipaddr
1341         */
1342        struct sockaddr_storage obs_rto_ipaddr;
1343        __u64 max_obs_rto;
1344        /* Total In and Out SACKs received and sent */
1345        __u64 isacks;
1346        __u64 osacks;
1347        /* Total In and Out packets received and sent */
1348        __u64 opackets;
1349        __u64 ipackets;
1350        /* Total retransmitted chunks */
1351        __u64 rtxchunks;
1352        /* TSN received > next expected */
1353        __u64 outofseqtsns;
1354        /* Duplicate Chunks received */
1355        __u64 idupchunks;
1356        /* Gap Ack Blocks received */
1357        __u64 gapcnt;
1358        /* Unordered data chunks sent and received */
1359        __u64 ouodchunks;
1360        __u64 iuodchunks;
1361        /* Ordered data chunks sent and received */
1362        __u64 oodchunks;
1363        __u64 iodchunks;
1364        /* Control chunks sent and received */
1365        __u64 octrlchunks;
1366        __u64 ictrlchunks;
1367};
1368
1369/* RFC2960
1370 *
1371 * 12. Recommended Transmission Control Block (TCB) Parameters
1372 *
1373 * This section details a recommended set of parameters that should
1374 * be contained within the TCB for an implementation. This section is
1375 * for illustrative purposes and should not be deemed as requirements
1376 * on an implementation or as an exhaustive list of all parameters
1377 * inside an SCTP TCB. Each implementation may need its own additional
1378 * parameters for optimization.
1379 */
1380
1381
1382/* Here we have information about each individual association. */
1383struct sctp_association {
1384
1385        /* A base structure common to endpoint and association.
1386         * In this context, it represents the associations's view
1387         * of the local endpoint of the association.
1388         */
1389        struct sctp_ep_common base;
1390
1391        /* Associations on the same socket. */
1392        struct list_head asocs;
1393
1394        /* association id. */
1395        sctp_assoc_t assoc_id;
1396
1397        /* This is our parent endpoint.  */
1398        struct sctp_endpoint *ep;
1399
1400        /* These are those association elements needed in the cookie.  */
1401        struct sctp_cookie c;
1402
1403        /* This is all information about our peer.  */
1404        struct {
1405                /* transport_addr_list
1406                 *
1407                 * Peer        : A list of SCTP transport addresses that the
1408                 * Transport   : peer is bound to. This information is derived
1409                 * Address     : from the INIT or INIT ACK and is used to
1410                 * List        : associate an inbound packet with a given
1411                 *             : association. Normally this information is
1412                 *             : hashed or keyed for quick lookup and access
1413                 *             : of the TCB.
1414                 *             : The list is also initialized with the list
1415                 *             : of addresses passed with the sctp_connectx()
1416                 *             : call.
1417                 *
1418                 * It is a list of SCTP_transport's.
1419                 */
1420                struct list_head transport_addr_list;
1421
1422                /* rwnd
1423                 *
1424                 * Peer Rwnd   : Current calculated value of the peer's rwnd.
1425                 */
1426                __u32 rwnd;
1427
1428                /* transport_count
1429                 *
1430                 * Peer        : A count of the number of peer addresses
1431                 * Transport   : in the Peer Transport Address List.
1432                 * Address     :
1433                 * Count       :
1434                 */
1435                __u16 transport_count;
1436
1437                /* port
1438                 *   The transport layer port number.
1439                 */
1440                __u16 port;
1441
1442                /* primary_path
1443                 *
1444                 * Primary     : This is the current primary destination
1445                 * Path        : transport address of the peer endpoint.  It
1446                 *             : may also specify a source transport address
1447                 *             : on this endpoint.
1448                 *
1449                 * All of these paths live on transport_addr_list.
1450                 *
1451                 * At the bakeoffs, we discovered that the intent of
1452                 * primaryPath is that it only changes when the ULP
1453                 * asks to have it changed.  We add the activePath to
1454                 * designate the connection we are currently using to
1455                 * transmit new data and most control chunks.
1456                 */
1457                struct sctp_transport *primary_path;
1458
1459                /* Cache the primary path address here, when we
1460                 * need a an address for msg_name.
1461                 */
1462                union sctp_addr primary_addr;
1463
1464                /* active_path
1465                 *   The path that we are currently using to
1466                 *   transmit new data and most control chunks.
1467                 */
1468                struct sctp_transport *active_path;
1469
1470                /* retran_path
1471                 *
1472                 * RFC2960 6.4 Multi-homed SCTP Endpoints
1473                 * ...
1474                 * Furthermore, when its peer is multi-homed, an
1475                 * endpoint SHOULD try to retransmit a chunk to an
1476                 * active destination transport address that is
1477                 * different from the last destination address to
1478                 * which the DATA chunk was sent.
1479                 */
1480                struct sctp_transport *retran_path;
1481
1482                /* Pointer to last transport I have sent on.  */
1483                struct sctp_transport *last_sent_to;
1484
1485                /* This is the last transport I have received DATA on.  */
1486                struct sctp_transport *last_data_from;
1487
1488                /*
1489                 * Mapping  An array of bits or bytes indicating which out of
1490                 * Array    order TSN's have been received (relative to the
1491                 *          Last Rcvd TSN). If no gaps exist, i.e. no out of
1492                 *          order packets have been received, this array
1493                 *          will be set to all zero. This structure may be
1494                 *          in the form of a circular buffer or bit array.
1495                 *
1496                 * Last Rcvd   : This is the last TSN received in
1497                 * TSN         : sequence. This value is set initially by
1498                 *             : taking the peer's Initial TSN, received in
1499                 *             : the INIT or INIT ACK chunk, and subtracting
1500                 *             : one from it.
1501                 *
1502                 * Throughout most of the specification this is called the
1503                 * "Cumulative TSN ACK Point".  In this case, we
1504                 * ignore the advice in 12.2 in favour of the term
1505                 * used in the bulk of the text.  This value is hidden
1506                 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1507                 */
1508                struct sctp_tsnmap tsn_map;
1509
1510                /* This mask is used to disable sending the ASCONF chunk
1511                 * with specified parameter to peer.
1512                 */
1513                __be16 addip_disabled_mask;
1514
1515                /* These are capabilities which our peer advertised.  */
1516                __u8    ecn_capable:1,      /* Can peer do ECN? */
1517                        ipv4_address:1,     /* Peer understands IPv4 addresses? */
1518                        ipv6_address:1,     /* Peer understands IPv6 addresses? */
1519                        hostname_address:1, /* Peer understands DNS addresses? */
1520                        asconf_capable:1,   /* Does peer support ADDIP? */
1521                        prsctp_capable:1,   /* Can peer do PR-SCTP? */
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        /* This tracks outbound ssn for a given stream.  */
1751        struct sctp_ssnmap *ssnmap;
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             prsctp_enable:1;
1882
1883        struct sctp_priv_assoc_stats stats;
1884
1885        int sent_cnt_removable;
1886
1887        __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1];
1888        __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1];
1889};
1890
1891
1892/* An eyecatcher for determining if we are really looking at an
1893 * association data structure.
1894 */
1895enum {
1896        SCTP_ASSOC_EYECATCHER = 0xa550c123,
1897};
1898
1899/* Recover the outter association structure. */
1900static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
1901{
1902        struct sctp_association *asoc;
1903
1904        asoc = container_of(base, struct sctp_association, base);
1905        return asoc;
1906}
1907
1908/* These are function signatures for manipulating associations.  */
1909
1910
1911struct sctp_association *
1912sctp_association_new(const struct sctp_endpoint *, const struct sock *,
1913                     sctp_scope_t scope, gfp_t gfp);
1914void sctp_association_free(struct sctp_association *);
1915void sctp_association_put(struct sctp_association *);
1916void sctp_association_hold(struct sctp_association *);
1917
1918struct sctp_transport *sctp_assoc_choose_alter_transport(
1919        struct sctp_association *, struct sctp_transport *);
1920void sctp_assoc_update_retran_path(struct sctp_association *);
1921struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
1922                                          const union sctp_addr *);
1923int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1924                            const union sctp_addr *laddr);
1925struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
1926                                     const union sctp_addr *address,
1927                                     const gfp_t gfp,
1928                                     const int peer_state);
1929void sctp_assoc_del_peer(struct sctp_association *asoc,
1930                         const union sctp_addr *addr);
1931void sctp_assoc_rm_peer(struct sctp_association *asoc,
1932                         struct sctp_transport *peer);
1933void sctp_assoc_control_transport(struct sctp_association *,
1934                                  struct sctp_transport *,
1935                                  sctp_transport_cmd_t, sctp_sn_error_t);
1936struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
1937struct sctp_transport *sctp_assoc_is_match(struct sctp_association *,
1938                                           struct net *,
1939                                           const union sctp_addr *,
1940                                           const union sctp_addr *);
1941void sctp_assoc_migrate(struct sctp_association *, struct sock *);
1942void sctp_assoc_update(struct sctp_association *old,
1943                       struct sctp_association *new);
1944
1945__u32 sctp_association_get_next_tsn(struct sctp_association *);
1946
1947void sctp_assoc_sync_pmtu(struct sock *, struct sctp_association *);
1948void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int);
1949void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int);
1950void sctp_assoc_set_primary(struct sctp_association *,
1951                            struct sctp_transport *);
1952void sctp_assoc_del_nonprimary_peers(struct sctp_association *,
1953                                    struct sctp_transport *);
1954int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *,
1955                                     sctp_scope_t, gfp_t);
1956int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
1957                                         struct sctp_cookie*,
1958                                         gfp_t gfp);
1959int sctp_assoc_set_id(struct sctp_association *, gfp_t);
1960void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc);
1961struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
1962                                        const struct sctp_association *asoc,
1963                                        __be32 serial);
1964void sctp_asconf_queue_teardown(struct sctp_association *asoc);
1965
1966int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1967                        const union sctp_addr *ss2);
1968struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
1969
1970/* A convenience structure to parse out SCTP specific CMSGs. */
1971typedef struct sctp_cmsgs {
1972        struct sctp_initmsg *init;
1973        struct sctp_sndrcvinfo *srinfo;
1974        struct sctp_sndinfo *sinfo;
1975} sctp_cmsgs_t;
1976
1977/* Structure for tracking memory objects */
1978typedef struct {
1979        char *label;
1980        atomic_t *counter;
1981} sctp_dbg_objcnt_entry_t;
1982
1983#endif /* __sctp_structs_h__ */
1984