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, write to
  23 * the Free Software Foundation, 59 Temple Place - Suite 330,
  24 * Boston, MA 02111-1307, USA.
  25 *
  26 * Please send any bug reports or fixes you make to the
  27 * email addresses:
  28 *    lksctp developers <lksctp-developers@lists.sourceforge.net>
  29 *
  30 * Or submit a bug report through the following website:
  31 *    http://www.sf.net/projects/lksctp
  32 *
  33 * Written or modified by:
  34 *    Randall Stewart       <randall@sctp.chicago.il.us>
  35 *    Ken Morneau           <kmorneau@cisco.com>
  36 *    Qiaobing Xie          <qxie1@email.mot.com>
  37 *    La Monte H.P. Yarroll <piggy@acm.org>
  38 *    Karl Knutson          <karl@athena.chicago.il.us>
  39 *    Jon Grimm             <jgrimm@us.ibm.com>
  40 *    Xingang Guo           <xingang.guo@intel.com>
  41 *    Hui Huang             <hui.huang@nokia.com>
  42 *    Sridhar Samudrala     <sri@us.ibm.com>
  43 *    Daisy Chang           <daisyc@us.ibm.com>
  44 *    Dajiang Zhang         <dajiang.zhang@nokia.com>
  45 *    Ardelle Fan           <ardelle.fan@intel.com>
  46 *    Ryan Layer            <rmlayer@us.ibm.com>
  47 *    Anup Pemmaiah         <pemmaiah@cc.usu.edu>
  48 *    Kevin Gao             <kevin.gao@intel.com>
  49 *
  50 * Any bugs reported given to us we will try to fix... any fixes shared will
  51 * be incorporated into the next SCTP release.
  52 */
  53
  54#ifndef __sctp_structs_h__
  55#define __sctp_structs_h__
  56
  57#include <linux/time.h>         /* We get struct timespec.    */
  58#include <linux/socket.h>       /* linux/in.h needs this!!    */
  59#include <linux/in.h>           /* We get struct sockaddr_in. */
  60#include <linux/in6.h>          /* We get struct in6_addr     */
  61#include <linux/ipv6.h>
  62#include <asm/param.h>          /* We get MAXHOSTNAMELEN.     */
  63#include <asm/atomic.h>         /* This gets us atomic counters.  */
  64#include <linux/skbuff.h>       /* We need sk_buff_head. */
  65#include <linux/workqueue.h>    /* We need tq_struct.    */
  66#include <linux/sctp.h>         /* We need sctp* header structs.  */
  67#include <net/sctp/auth.h>      /* We need auth specific structs */
  68
  69/* A convenience structure for handling sockaddr structures.
  70 * We should wean ourselves off this.
  71 */
  72union sctp_addr {
  73        struct sockaddr_in v4;
  74        struct sockaddr_in6 v6;
  75        struct sockaddr sa;
  76};
  77
  78/* Forward declarations for data structures. */
  79struct sctp_globals;
  80struct sctp_endpoint;
  81struct sctp_association;
  82struct sctp_transport;
  83struct sctp_packet;
  84struct sctp_chunk;
  85struct sctp_inq;
  86struct sctp_outq;
  87struct sctp_bind_addr;
  88struct sctp_ulpq;
  89struct sctp_ep_common;
  90struct sctp_ssnmap;
  91struct crypto_hash;
  92
  93
  94#include <net/sctp/tsnmap.h>
  95#include <net/sctp/ulpevent.h>
  96#include <net/sctp/ulpqueue.h>
  97
  98/* Structures useful for managing bind/connect. */
  99
 100struct sctp_bind_bucket {
 101        unsigned short  port;
 102        unsigned short  fastreuse;
 103        struct hlist_node       node;
 104        struct hlist_head       owner;
 105};
 106
 107struct sctp_bind_hashbucket {
 108        spinlock_t      lock;
 109        struct hlist_head       chain;
 110};
 111
 112/* Used for hashing all associations.  */
 113struct sctp_hashbucket {
 114        rwlock_t        lock;
 115        struct hlist_head       chain;
 116} __attribute__((__aligned__(8)));
 117
 118
 119/* The SCTP globals structure. */
 120extern struct sctp_globals {
 121        /* RFC2960 Section 14. Suggested SCTP Protocol Parameter Values
 122         *
 123         * The following protocol parameters are RECOMMENDED:
 124         *
 125         * RTO.Initial              - 3  seconds
 126         * RTO.Min                  - 1  second
 127         * RTO.Max                 -  60 seconds
 128         * RTO.Alpha                - 1/8  (3 when converted to right shifts.)
 129         * RTO.Beta                 - 1/4  (2 when converted to right shifts.)
 130         */
 131        unsigned int rto_initial;
 132        unsigned int rto_min;
 133        unsigned int rto_max;
 134
 135        /* Note: rto_alpha and rto_beta are really defined as inverse
 136         * powers of two to facilitate integer operations.
 137         */
 138        int rto_alpha;
 139        int rto_beta;
 140
 141        /* Max.Burst                - 4 */
 142        int max_burst;
 143
 144        /* Whether Cookie Preservative is enabled(1) or not(0) */
 145        int cookie_preserve_enable;
 146
 147        /* Valid.Cookie.Life        - 60  seconds  */
 148        unsigned int valid_cookie_life;
 149
 150        /* Delayed SACK timeout  200ms default*/
 151        unsigned int sack_timeout;
 152
 153        /* HB.interval              - 30 seconds  */
 154        unsigned int hb_interval;
 155
 156        /* Association.Max.Retrans  - 10 attempts
 157         * Path.Max.Retrans         - 5  attempts (per destination address)
 158         * Max.Init.Retransmits     - 8  attempts
 159         */
 160        int max_retrans_association;
 161        int max_retrans_path;
 162        int max_retrans_init;
 163
 164        /*
 165         * Policy for preforming sctp/socket accounting
 166         * 0   - do socket level accounting, all assocs share sk_sndbuf
 167         * 1   - do sctp accounting, each asoc may use sk_sndbuf bytes
 168         */
 169        int sndbuf_policy;
 170
 171        /*
 172         * Policy for preforming sctp/socket accounting
 173         * 0   - do socket level accounting, all assocs share sk_rcvbuf
 174         * 1   - do sctp accounting, each asoc may use sk_rcvbuf bytes
 175         */
 176        int rcvbuf_policy;
 177
 178        /* The following variables are implementation specific.  */
 179
 180        /* Default initialization values to be applied to new associations. */
 181        __u16 max_instreams;
 182        __u16 max_outstreams;
 183
 184        /* This is a list of groups of functions for each address
 185         * family that we support.
 186         */
 187        struct list_head address_families;
 188
 189        /* This is the hash of all endpoints. */
 190        int ep_hashsize;
 191        struct sctp_hashbucket *ep_hashtable;
 192
 193        /* This is the hash of all associations. */
 194        int assoc_hashsize;
 195        struct sctp_hashbucket *assoc_hashtable;
 196
 197        /* This is the sctp port control hash.  */
 198        int port_hashsize;
 199        struct sctp_bind_hashbucket *port_hashtable;
 200
 201        /* This is the global local address list.
 202         * We actively maintain this complete list of addresses on
 203         * the system by catching address add/delete events.
 204         *
 205         * It is a list of sctp_sockaddr_entry.
 206         */
 207        struct list_head local_addr_list;
 208
 209        /* Lock that protects the local_addr_list writers */
 210        spinlock_t addr_list_lock;
 211        
 212        /* Flag to indicate if addip is enabled. */
 213        int addip_enable;
 214        int addip_noauth_enable;
 215
 216        /* Flag to indicate if PR-SCTP is enabled. */
 217        int prsctp_enable;
 218
 219        /* Flag to idicate if SCTP-AUTH is enabled */
 220        int auth_enable;
 221
 222        /*
 223         * Policy to control SCTP IPv4 address scoping
 224         * 0   - Disable IPv4 address scoping
 225         * 1   - Enable IPv4 address scoping
 226         * 2   - Selectively allow only IPv4 private addresses
 227         * 3   - Selectively allow only IPv4 link local address
 228         */
 229        int ipv4_scope_policy;
 230
 231        /* Flag to indicate whether computing and verifying checksum
 232         * is disabled. */
 233        int checksum_disable;
 234} sctp_globals;
 235
 236#define sctp_rto_initial                (sctp_globals.rto_initial)
 237#define sctp_rto_min                    (sctp_globals.rto_min)
 238#define sctp_rto_max                    (sctp_globals.rto_max)
 239#define sctp_rto_alpha                  (sctp_globals.rto_alpha)
 240#define sctp_rto_beta                   (sctp_globals.rto_beta)
 241#define sctp_max_burst                  (sctp_globals.max_burst)
 242#define sctp_valid_cookie_life          (sctp_globals.valid_cookie_life)
 243#define sctp_cookie_preserve_enable     (sctp_globals.cookie_preserve_enable)
 244#define sctp_max_retrans_association    (sctp_globals.max_retrans_association)
 245#define sctp_sndbuf_policy              (sctp_globals.sndbuf_policy)
 246#define sctp_rcvbuf_policy              (sctp_globals.rcvbuf_policy)
 247#define sctp_max_retrans_path           (sctp_globals.max_retrans_path)
 248#define sctp_max_retrans_init           (sctp_globals.max_retrans_init)
 249#define sctp_sack_timeout               (sctp_globals.sack_timeout)
 250#define sctp_hb_interval                (sctp_globals.hb_interval)
 251#define sctp_max_instreams              (sctp_globals.max_instreams)
 252#define sctp_max_outstreams             (sctp_globals.max_outstreams)
 253#define sctp_address_families           (sctp_globals.address_families)
 254#define sctp_ep_hashsize                (sctp_globals.ep_hashsize)
 255#define sctp_ep_hashtable               (sctp_globals.ep_hashtable)
 256#define sctp_assoc_hashsize             (sctp_globals.assoc_hashsize)
 257#define sctp_assoc_hashtable            (sctp_globals.assoc_hashtable)
 258#define sctp_port_hashsize              (sctp_globals.port_hashsize)
 259#define sctp_port_rover                 (sctp_globals.port_rover)
 260#define sctp_port_alloc_lock            (sctp_globals.port_alloc_lock)
 261#define sctp_port_hashtable             (sctp_globals.port_hashtable)
 262#define sctp_local_addr_list            (sctp_globals.local_addr_list)
 263#define sctp_local_addr_lock            (sctp_globals.addr_list_lock)
 264#define sctp_scope_policy               (sctp_globals.ipv4_scope_policy)
 265#define sctp_addip_enable               (sctp_globals.addip_enable)
 266#define sctp_addip_noauth               (sctp_globals.addip_noauth_enable)
 267#define sctp_prsctp_enable              (sctp_globals.prsctp_enable)
 268#define sctp_auth_enable                (sctp_globals.auth_enable)
 269#define sctp_checksum_disable           (sctp_globals.checksum_disable)
 270
 271/* SCTP Socket type: UDP or TCP style. */
 272typedef enum {
 273        SCTP_SOCKET_UDP = 0,
 274        SCTP_SOCKET_UDP_HIGH_BANDWIDTH,
 275        SCTP_SOCKET_TCP
 276} sctp_socket_type_t;
 277
 278/* Per socket SCTP information. */
 279struct sctp_sock {
 280        /* inet_sock has to be the first member of sctp_sock */
 281        struct inet_sock inet;
 282        /* What kind of a socket is this? */
 283        sctp_socket_type_t type;
 284
 285        /* PF_ family specific functions.  */
 286        struct sctp_pf *pf;
 287
 288        /* Access to HMAC transform. */
 289        struct crypto_hash *hmac;
 290
 291        /* What is our base endpointer? */
 292        struct sctp_endpoint *ep;
 293
 294        struct sctp_bind_bucket *bind_hash;
 295        /* Various Socket Options.  */
 296        __u16 default_stream;
 297        __u32 default_ppid;
 298        __u16 default_flags;
 299        __u32 default_context;
 300        __u32 default_timetolive;
 301        __u32 default_rcv_context;
 302        int max_burst;
 303
 304        /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
 305         * the destination address every heartbeat interval. This value
 306         * will be inherited by all new associations.
 307         */
 308        __u32 hbinterval;
 309
 310        /* This is the max_retrans value for new associations. */
 311        __u16 pathmaxrxt;
 312
 313        /* The initial Path MTU to use for new associations. */
 314        __u32 pathmtu;
 315
 316        /* The default SACK delay timeout for new associations. */
 317        __u32 sackdelay;
 318        __u32 sackfreq;
 319
 320        /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
 321        __u32 param_flags;
 322
 323        struct sctp_initmsg initmsg;
 324        struct sctp_rtoinfo rtoinfo;
 325        struct sctp_paddrparams paddrparam;
 326        struct sctp_event_subscribe subscribe;
 327        struct sctp_assocparams assocparams;
 328        int user_frag;
 329        __u32 autoclose;
 330        __u8 nodelay;
 331        __u8 disable_fragments;
 332        __u8 v4mapped;
 333        __u8 frag_interleave;
 334        __u32 adaptation_ind;
 335        __u32 pd_point;
 336
 337        atomic_t pd_mode;
 338        /* Receive to here while partial delivery is in effect. */
 339        struct sk_buff_head pd_lobby;
 340};
 341
 342static inline struct sctp_sock *sctp_sk(const struct sock *sk)
 343{
 344       return (struct sctp_sock *)sk;
 345}
 346
 347static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
 348{
 349       return (struct sock *)sp;
 350}
 351
 352#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 353struct sctp6_sock {
 354       struct sctp_sock  sctp;
 355       struct ipv6_pinfo inet6;
 356};
 357#endif /* CONFIG_IPV6 */
 358
 359
 360/* This is our APPLICATION-SPECIFIC state cookie.
 361 * THIS IS NOT DICTATED BY THE SPECIFICATION.
 362 */
 363/* These are the parts of an association which we send in the cookie.
 364 * Most of these are straight out of:
 365 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
 366 *
 367 */
 368
 369struct sctp_cookie {
 370
 371        /* My          : Tag expected in every inbound packet and sent
 372         * Verification: in the INIT or INIT ACK chunk.
 373         * Tag         :
 374         */
 375        __u32 my_vtag;
 376
 377        /* Peer's      : Tag expected in every outbound packet except
 378         * Verification: in the INIT chunk.
 379         * Tag         :
 380         */
 381        __u32 peer_vtag;
 382
 383        /* The rest of these are not from the spec, but really need to
 384         * be in the cookie.
 385         */
 386
 387        /* My Tie Tag  : Assist in discovering a restarting association. */
 388        __u32 my_ttag;
 389
 390        /* Peer's Tie Tag: Assist in discovering a restarting association. */
 391        __u32 peer_ttag;
 392
 393        /* When does this cookie expire? */
 394        struct timeval expiration;
 395
 396        /* Number of inbound/outbound streams which are set
 397         * and negotiated during the INIT process.
 398         */
 399        __u16 sinit_num_ostreams;
 400        __u16 sinit_max_instreams;
 401
 402        /* This is the first sequence number I used.  */
 403        __u32 initial_tsn;
 404
 405        /* This holds the originating address of the INIT packet.  */
 406        union sctp_addr peer_addr;
 407
 408        /* IG Section 2.35.3 
 409         * Include the source port of the INIT-ACK
 410         */
 411        __u16           my_port;
 412
 413        __u8 prsctp_capable;
 414
 415        /* Padding for future use */
 416        __u8 padding;           
 417
 418        __u32 adaptation_ind;
 419
 420        __u8 auth_random[sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH];
 421        __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS + 2];
 422        __u8 auth_chunks[sizeof(sctp_paramhdr_t) + SCTP_AUTH_MAX_CHUNKS];
 423
 424        /* This is a shim for my peer's INIT packet, followed by
 425         * a copy of the raw address list of the association.
 426         * The length of the raw address list is saved in the
 427         * raw_addr_list_len field, which will be used at the time when
 428         * the association TCB is re-constructed from the cookie.
 429         */
 430        __u32 raw_addr_list_len;
 431        struct sctp_init_chunk peer_init[0];
 432};
 433
 434
 435/* The format of our cookie that we send to our peer. */
 436struct sctp_signed_cookie {
 437        __u8 signature[SCTP_SECRET_SIZE];
 438        __u32 __pad;            /* force sctp_cookie alignment to 64 bits */
 439        struct sctp_cookie c;
 440} __attribute__((packed));
 441
 442/* This is another convenience type to allocate memory for address
 443 * params for the maximum size and pass such structures around
 444 * internally.
 445 */
 446union sctp_addr_param {
 447        struct sctp_paramhdr p;
 448        struct sctp_ipv4addr_param v4;
 449        struct sctp_ipv6addr_param v6;
 450};
 451
 452/* A convenience type to allow walking through the various
 453 * parameters and avoid casting all over the place.
 454 */
 455union sctp_params {
 456        void *v;
 457        struct sctp_paramhdr *p;
 458        struct sctp_cookie_preserve_param *life;
 459        struct sctp_hostname_param *dns;
 460        struct sctp_cookie_param *cookie;
 461        struct sctp_supported_addrs_param *sat;
 462        struct sctp_ipv4addr_param *v4;
 463        struct sctp_ipv6addr_param *v6;
 464        union sctp_addr_param *addr;
 465        struct sctp_adaptation_ind_param *aind;
 466        struct sctp_supported_ext_param *ext;
 467        struct sctp_random_param *random;
 468        struct sctp_chunks_param *chunks;
 469        struct sctp_hmac_algo_param *hmac_algo;
 470        struct sctp_addip_param *addip;
 471};
 472
 473/* RFC 2960.  Section 3.3.5 Heartbeat.
 474 *    Heartbeat Information: variable length
 475 *    The Sender-specific Heartbeat Info field should normally include
 476 *    information about the sender's current time when this HEARTBEAT
 477 *    chunk is sent and the destination transport address to which this
 478 *    HEARTBEAT is sent (see Section 8.3).
 479 */
 480typedef struct sctp_sender_hb_info {
 481        struct sctp_paramhdr param_hdr;
 482        union sctp_addr daddr;
 483        unsigned long sent_at;
 484        __u64 hb_nonce;
 485} __attribute__((packed)) sctp_sender_hb_info_t;
 486
 487/*
 488 *  RFC 2960 1.3.2 Sequenced Delivery within Streams
 489 *
 490 *  The term "stream" is used in SCTP to refer to a sequence of user
 491 *  messages that are to be delivered to the upper-layer protocol in
 492 *  order with respect to other messages within the same stream.  This is
 493 *  in contrast to its usage in TCP, where it refers to a sequence of
 494 *  bytes (in this document a byte is assumed to be eight bits).
 495 *  ...
 496 *
 497 *  This is the structure we use to track both our outbound and inbound
 498 *  SSN, or Stream Sequence Numbers.
 499 */
 500
 501struct sctp_stream {
 502        __u16 *ssn;
 503        unsigned int len;
 504};
 505
 506struct sctp_ssnmap {
 507        struct sctp_stream in;
 508        struct sctp_stream out;
 509        int malloced;
 510};
 511
 512struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out,
 513                                    gfp_t gfp);
 514void sctp_ssnmap_free(struct sctp_ssnmap *map);
 515void sctp_ssnmap_clear(struct sctp_ssnmap *map);
 516
 517/* What is the current SSN number for this stream? */
 518static inline __u16 sctp_ssn_peek(struct sctp_stream *stream, __u16 id)
 519{
 520        return stream->ssn[id];
 521}
 522
 523/* Return the next SSN number for this stream.  */
 524static inline __u16 sctp_ssn_next(struct sctp_stream *stream, __u16 id)
 525{
 526        return stream->ssn[id]++;
 527}
 528
 529/* Skip over this ssn and all below. */
 530static inline void sctp_ssn_skip(struct sctp_stream *stream, __u16 id, 
 531                                 __u16 ssn)
 532{
 533        stream->ssn[id] = ssn+1;
 534}
 535              
 536/*
 537 * Pointers to address related SCTP functions.
 538 * (i.e. things that depend on the address family.)
 539 */
 540struct sctp_af {
 541        int             (*sctp_xmit)    (struct sk_buff *skb,
 542                                         struct sctp_transport *);
 543        int             (*setsockopt)   (struct sock *sk,
 544                                         int level,
 545                                         int optname,
 546                                         char __user *optval,
 547                                         unsigned int optlen);
 548        int             (*getsockopt)   (struct sock *sk,
 549                                         int level,
 550                                         int optname,
 551                                         char __user *optval,
 552                                         int __user *optlen);
 553        int             (*compat_setsockopt)    (struct sock *sk,
 554                                         int level,
 555                                         int optname,
 556                                         char __user *optval,
 557                                         unsigned int optlen);
 558        int             (*compat_getsockopt)    (struct sock *sk,
 559                                         int level,
 560                                         int optname,
 561                                         char __user *optval,
 562                                         int __user *optlen);
 563        struct dst_entry *(*get_dst)    (struct sctp_association *asoc,
 564                                         union sctp_addr *daddr,
 565                                         union sctp_addr *saddr);
 566        void            (*get_saddr)    (struct sctp_sock *sk,
 567                                         struct sctp_association *asoc,
 568                                         struct dst_entry *dst,
 569                                         union sctp_addr *daddr,
 570                                         union sctp_addr *saddr);
 571        void            (*copy_addrlist) (struct list_head *,
 572                                          struct net_device *);
 573        void            (*dst_saddr)    (union sctp_addr *saddr,
 574                                         struct dst_entry *dst,
 575                                         __be16 port);
 576        int             (*cmp_addr)     (const union sctp_addr *addr1,
 577                                         const union sctp_addr *addr2);
 578        void            (*addr_copy)    (union sctp_addr *dst,
 579                                         union sctp_addr *src);
 580        void            (*from_skb)     (union sctp_addr *,
 581                                         struct sk_buff *skb,
 582                                         int saddr);
 583        void            (*from_sk)      (union sctp_addr *,
 584                                         struct sock *sk);
 585        void            (*to_sk_saddr)  (union sctp_addr *,
 586                                         struct sock *sk);
 587        void            (*to_sk_daddr)  (union sctp_addr *,
 588                                         struct sock *sk);
 589        void            (*from_addr_param) (union sctp_addr *,
 590                                            union sctp_addr_param *,
 591                                            __be16 port, int iif);
 592        int             (*to_addr_param) (const union sctp_addr *,
 593                                          union sctp_addr_param *); 
 594        int             (*addr_valid)   (union sctp_addr *,
 595                                         struct sctp_sock *,
 596                                         const struct sk_buff *);
 597        sctp_scope_t    (*scope) (union sctp_addr *);
 598        void            (*inaddr_any)   (union sctp_addr *, __be16);
 599        int             (*is_any)       (const union sctp_addr *);
 600        int             (*available)    (union sctp_addr *,
 601                                         struct sctp_sock *);
 602        int             (*skb_iif)      (const struct sk_buff *sk);
 603        int             (*is_ce)        (const struct sk_buff *sk);
 604        void            (*seq_dump_addr)(struct seq_file *seq,
 605                                         union sctp_addr *addr);
 606        void            (*ecn_capable)(struct sock *sk);
 607        __u16           net_header_len;
 608        int             sockaddr_len;
 609        sa_family_t     sa_family;
 610        struct list_head list;
 611};
 612
 613struct sctp_af *sctp_get_af_specific(sa_family_t);
 614int sctp_register_af(struct sctp_af *);
 615
 616/* Protocol family functions. */
 617struct sctp_pf {
 618        void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
 619        void (*skb_msgname)  (struct sk_buff *, char *, int *);
 620        int  (*af_supported) (sa_family_t, struct sctp_sock *);
 621        int  (*cmp_addr) (const union sctp_addr *,
 622                          const union sctp_addr *,
 623                          struct sctp_sock *);
 624        int  (*bind_verify) (struct sctp_sock *, union sctp_addr *);
 625        int  (*send_verify) (struct sctp_sock *, union sctp_addr *);
 626        int  (*supported_addrs)(const struct sctp_sock *, __be16 *);
 627        struct sock *(*create_accept_sk) (struct sock *sk,
 628                                          struct sctp_association *asoc);
 629        void (*addr_v4map) (struct sctp_sock *, union sctp_addr *);
 630        struct sctp_af *af;
 631};
 632
 633
 634/* Structure to track chunk fragments that have been acked, but peer
 635 * fragments of the same message have not.
 636 */
 637struct sctp_datamsg {
 638        /* Chunks waiting to be submitted to lower layer. */
 639        struct list_head chunks;
 640        /* Chunks that have been transmitted. */
 641        size_t msg_size;
 642        /* Reference counting. */
 643        atomic_t refcnt;
 644        /* When is this message no longer interesting to the peer? */
 645        unsigned long expires_at;
 646        /* Did the messenge fail to send? */
 647        int send_error;
 648        char send_failed;
 649        /* Control whether chunks from this message can be abandoned. */
 650        char can_abandon;
 651};
 652
 653struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
 654                                            struct sctp_sndrcvinfo *,
 655                                            struct msghdr *, int len);
 656void sctp_datamsg_free(struct sctp_datamsg *);
 657void sctp_datamsg_put(struct sctp_datamsg *);
 658void sctp_chunk_fail(struct sctp_chunk *, int error);
 659int sctp_chunk_abandoned(struct sctp_chunk *);
 660
 661/* RFC2960 1.4 Key Terms
 662 *
 663 * o Chunk: A unit of information within an SCTP packet, consisting of
 664 * a chunk header and chunk-specific content.
 665 *
 666 * As a matter of convenience, we remember the SCTP common header for
 667 * each chunk as well as a few other header pointers...
 668 */
 669struct sctp_chunk {
 670        struct list_head list;
 671
 672        atomic_t refcnt;
 673
 674        /* This is our link to the per-transport transmitted list.  */
 675        struct list_head transmitted_list;
 676
 677        /* This field is used by chunks that hold fragmented data.
 678         * For the first fragment this is the list that holds the rest of
 679         * fragments. For the remaining fragments, this is the link to the
 680         * frag_list maintained in the first fragment.
 681         */
 682        struct list_head frag_list;
 683
 684        /* This points to the sk_buff containing the actual data.  */
 685        struct sk_buff *skb;
 686
 687        /* These are the SCTP headers by reverse order in a packet.
 688         * Note that some of these may happen more than once.  In that
 689         * case, we point at the "current" one, whatever that means
 690         * for that level of header.
 691         */
 692
 693        /* We point this at the FIRST TLV parameter to chunk_hdr.  */
 694        union sctp_params param_hdr;
 695        union {
 696                __u8 *v;
 697                struct sctp_datahdr *data_hdr;
 698                struct sctp_inithdr *init_hdr;
 699                struct sctp_sackhdr *sack_hdr;
 700                struct sctp_heartbeathdr *hb_hdr;
 701                struct sctp_sender_hb_info *hbs_hdr;
 702                struct sctp_shutdownhdr *shutdown_hdr;
 703                struct sctp_signed_cookie *cookie_hdr;
 704                struct sctp_ecnehdr *ecne_hdr;
 705                struct sctp_cwrhdr *ecn_cwr_hdr;
 706                struct sctp_errhdr *err_hdr;
 707                struct sctp_addiphdr *addip_hdr;
 708                struct sctp_fwdtsn_hdr *fwdtsn_hdr;
 709                struct sctp_authhdr *auth_hdr;
 710        } subh;
 711
 712        __u8 *chunk_end;
 713
 714        struct sctp_chunkhdr *chunk_hdr;
 715        struct sctphdr *sctp_hdr;
 716
 717        /* This needs to be recoverable for SCTP_SEND_FAILED events. */
 718        struct sctp_sndrcvinfo sinfo;
 719
 720        /* Which association does this belong to?  */
 721        struct sctp_association *asoc;
 722
 723        /* What endpoint received this chunk? */
 724        struct sctp_ep_common *rcvr;
 725
 726        /* We fill this in if we are calculating RTT. */
 727        unsigned long sent_at;
 728
 729        /* What is the origin IP address for this chunk?  */
 730        union sctp_addr source;
 731        /* Destination address for this chunk. */
 732        union sctp_addr dest;
 733
 734        /* For outbound message, track all fragments for SEND_FAILED. */
 735        struct sctp_datamsg *msg;
 736
 737        /* For an inbound chunk, this tells us where it came from.
 738         * For an outbound chunk, it tells us where we'd like it to
 739         * go.  It is NULL if we have no preference.
 740         */
 741        struct sctp_transport *transport;
 742
 743        /* SCTP-AUTH:  For the special case inbound processing of COOKIE-ECHO
 744         * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
 745         * spec violates the principle premis that all chunks are processed
 746         * in order.
 747         */
 748        struct sk_buff *auth_chunk;
 749
 750#define SCTP_CAN_FRTX 0x0
 751#define SCTP_NEED_FRTX 0x1
 752#define SCTP_DONT_FRTX 0x2
 753        __u16   rtt_in_progress:1,      /* This chunk used for RTT calc? */
 754                resent:1,               /* Has this chunk ever been resent. */
 755                has_tsn:1,              /* Does this chunk have a TSN yet? */
 756                has_ssn:1,              /* Does this chunk have a SSN yet? */
 757                singleton:1,            /* Only chunk in the packet? */
 758                end_of_packet:1,        /* Last chunk in the packet? */
 759                ecn_ce_done:1,          /* Have we processed the ECN CE bit? */
 760                pdiscard:1,             /* Discard the whole packet now? */
 761                tsn_gap_acked:1,        /* Is this chunk acked by a GAP ACK? */
 762                data_accepted:1,        /* At least 1 chunk accepted */
 763                auth:1,                 /* IN: was auth'ed | OUT: needs auth */
 764                has_asconf:1,           /* IN: have seen an asconf before */
 765                tsn_missing_report:2,   /* Data chunk missing counter. */
 766                fast_retransmit:2;      /* Is this chunk fast retransmitted? */
 767};
 768
 769void sctp_chunk_hold(struct sctp_chunk *);
 770void sctp_chunk_put(struct sctp_chunk *);
 771int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
 772                          struct iovec *data);
 773void sctp_chunk_free(struct sctp_chunk *);
 774void  *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
 775struct sctp_chunk *sctp_chunkify(struct sk_buff *,
 776                                 const struct sctp_association *,
 777                                 struct sock *);
 778void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
 779                     union sctp_addr *);
 780const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
 781
 782enum {
 783        SCTP_ADDR_NEW,          /* new address added to assoc/ep */
 784        SCTP_ADDR_SRC,          /* address can be used as source */
 785        SCTP_ADDR_DEL,          /* address about to be deleted */
 786};
 787
 788/* This is a structure for holding either an IPv6 or an IPv4 address.  */
 789struct sctp_sockaddr_entry {
 790        struct list_head list;
 791        struct rcu_head rcu;
 792        union sctp_addr a;
 793        __u8 state;
 794        __u8 valid;
 795};
 796
 797typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *);
 798
 799/* This structure holds lists of chunks as we are assembling for
 800 * transmission.
 801 */
 802struct sctp_packet {
 803        /* These are the SCTP header values (host order) for the packet. */
 804        __u16 source_port;
 805        __u16 destination_port;
 806        __u32 vtag;
 807
 808        /* This contains the payload chunks.  */
 809        struct list_head chunk_list;
 810
 811        /* This is the overhead of the sctp and ip headers. */
 812        size_t overhead;
 813        /* This is the total size of all chunks INCLUDING padding.  */
 814        size_t size;
 815
 816        /* The packet is destined for this transport address.
 817         * The function we finally use to pass down to the next lower
 818         * layer lives in the transport structure.
 819         */
 820        struct sctp_transport *transport;
 821
 822        /* pointer to the auth chunk for this packet */
 823        struct sctp_chunk *auth;
 824
 825        u8  has_cookie_echo:1,  /* This packet contains a COOKIE-ECHO chunk. */
 826            has_sack:1,         /* This packet contains a SACK chunk. */
 827            has_auth:1,         /* This packet contains an AUTH chunk */
 828            has_data:1,         /* This packet contains at least 1 DATA chunk */
 829            ipfragok:1,         /* So let ip fragment this packet */
 830            malloced:1;         /* Is it malloced? */
 831};
 832
 833struct sctp_packet *sctp_packet_init(struct sctp_packet *,
 834                                     struct sctp_transport *,
 835                                     __u16 sport, __u16 dport);
 836struct sctp_packet *sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
 837sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *,
 838                                       struct sctp_chunk *, int);
 839sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *,
 840                                     struct sctp_chunk *);
 841int sctp_packet_transmit(struct sctp_packet *);
 842void sctp_packet_free(struct sctp_packet *);
 843
 844static inline int sctp_packet_empty(struct sctp_packet *packet)
 845{
 846        return (packet->size == packet->overhead);
 847}
 848
 849/* This represents a remote transport address.
 850 * For local transport addresses, we just use union sctp_addr.
 851 *
 852 * RFC2960 Section 1.4 Key Terms
 853 *
 854 *   o  Transport address:  A Transport Address is traditionally defined
 855 *      by Network Layer address, Transport Layer protocol and Transport
 856 *      Layer port number.  In the case of SCTP running over IP, a
 857 *      transport address is defined by the combination of an IP address
 858 *      and an SCTP port number (where SCTP is the Transport protocol).
 859 *
 860 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
 861 *
 862 *   o  The sender keeps a separate congestion control parameter set for
 863 *      each of the destination addresses it can send to (not each
 864 *      source-destination pair but for each destination).  The parameters
 865 *      should decay if the address is not used for a long enough time
 866 *      period.
 867 *
 868 */
 869struct sctp_transport {
 870        /* A list of transports. */
 871        struct list_head transports;
 872
 873        /* Reference counting. */
 874        atomic_t refcnt;
 875        int      dead;
 876
 877        /* This is the peer's IP address and port. */
 878        union sctp_addr ipaddr;
 879
 880        /* These are the functions we call to handle LLP stuff.  */
 881        struct sctp_af *af_specific;
 882
 883        /* Which association do we belong to?  */
 884        struct sctp_association *asoc;
 885
 886        /* RFC2960
 887         *
 888         * 12.3 Per Transport Address Data
 889         *
 890         * For each destination transport address in the peer's
 891         * address list derived from the INIT or INIT ACK chunk, a
 892         * number of data elements needs to be maintained including:
 893         */
 894        /* RTO         : The current retransmission timeout value.  */
 895        unsigned long rto;
 896
 897        __u32 rtt;              /* This is the most recent RTT.  */
 898
 899        /* RTTVAR      : The current RTT variation.  */
 900        __u32 rttvar;
 901
 902        /* SRTT        : The current smoothed round trip time.  */
 903        __u32 srtt;
 904
 905        /* RTO-Pending : A flag used to track if one of the DATA
 906         *              chunks sent to this address is currently being
 907         *              used to compute a RTT. If this flag is 0,
 908         *              the next DATA chunk sent to this destination
 909         *              should be used to compute a RTT and this flag
 910         *              should be set. Every time the RTT
 911         *              calculation completes (i.e. the DATA chunk
 912         *              is SACK'd) clear this flag.
 913         * hb_sent : a flag that signals that we have a pending heartbeat.
 914         */
 915        __u8 rto_pending;
 916        __u8 hb_sent;
 917
 918        /* Flag to track the current fast recovery state */
 919        __u8 fast_recovery;
 920
 921        /*
 922         * These are the congestion stats.
 923         */
 924        /* cwnd        : The current congestion window.  */
 925        __u32 cwnd;               /* This is the actual cwnd.  */
 926
 927        /* ssthresh    : The current slow start threshold value.  */
 928        __u32 ssthresh;
 929
 930        /* partial     : The tracking method for increase of cwnd when in
 931         * bytes acked : congestion avoidance mode (see Section 6.2.2)
 932         */
 933        __u32 partial_bytes_acked;
 934
 935        /* Data that has been sent, but not acknowledged. */
 936        __u32 flight_size;
 937
 938        /* TSN marking the fast recovery exit point */
 939        __u32 fast_recovery_exit;
 940
 941        /* Destination */
 942        struct dst_entry *dst;
 943        /* Source address. */
 944        union sctp_addr saddr;
 945
 946        /* When was the last time(in jiffies) that a data packet was sent on
 947         * this transport?  This is used to adjust the cwnd when the transport
 948         * becomes inactive.
 949         */
 950        unsigned long last_time_used;
 951
 952        /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
 953         * the destination address every heartbeat interval.
 954         */
 955        unsigned long hbinterval;
 956
 957        /* SACK delay timeout */
 958        unsigned long sackdelay;
 959        __u32 sackfreq;
 960
 961        /* When was the last time (in jiffies) that we heard from this
 962         * transport?  We use this to pick new active and retran paths.
 963         */
 964        unsigned long last_time_heard;
 965
 966        /* Last time(in jiffies) when cwnd is reduced due to the congestion
 967         * indication based on ECNE chunk.
 968         */
 969        unsigned long last_time_ecne_reduced;
 970
 971        /* This is the max_retrans value for the transport and will
 972         * be initialized from the assocs value.  This can be changed
 973         * using SCTP_SET_PEER_ADDR_PARAMS socket option.
 974         */
 975        __u16 pathmaxrxt;
 976
 977        /* is the Path MTU update pending on this tranport */
 978        __u8 pmtu_pending;
 979
 980        /* PMTU       : The current known path MTU.  */
 981        __u32 pathmtu;
 982
 983        /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
 984        __u32 param_flags;
 985
 986        /* The number of times INIT has been sent on this transport. */
 987        int init_sent_count;
 988
 989        /* state       : The current state of this destination,
 990         *             : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKOWN.
 991         */
 992        int state;
 993
 994        /* These are the error stats for this destination.  */
 995
 996        /* Error count : The current error count for this destination.  */
 997        unsigned short error_count;
 998
 999        /* Per         : A timer used by each destination.
1000         * Destination :
1001         * Timer       :
1002         *
1003         * [Everywhere else in the text this is called T3-rtx. -ed]
1004         */
1005        struct timer_list T3_rtx_timer;
1006
1007        /* Heartbeat timer is per destination. */
1008        struct timer_list hb_timer;
1009
1010        /* Since we're using per-destination retransmission timers
1011         * (see above), we're also using per-destination "transmitted"
1012         * queues.  This probably ought to be a private struct
1013         * accessible only within the outqueue, but it's not, yet.
1014         */
1015        struct list_head transmitted;
1016
1017        /* We build bundle-able packets for this transport here.  */
1018        struct sctp_packet packet;
1019
1020        /* This is the list of transports that have chunks to send.  */
1021        struct list_head send_ready;
1022
1023        int malloced; /* Is this structure kfree()able? */
1024
1025        /* State information saved for SFR_CACC algorithm. The key
1026         * idea in SFR_CACC is to maintain state at the sender on a
1027         * per-destination basis when a changeover happens.
1028         *      char changeover_active;
1029         *      char cycling_changeover;
1030         *      __u32 next_tsn_at_change;
1031         *      char cacc_saw_newack;
1032         */
1033        struct {
1034                /* An unsigned integer, which stores the next TSN to be
1035                 * used by the sender, at the moment of changeover.
1036                 */
1037                __u32 next_tsn_at_change;
1038
1039                /* A flag which indicates the occurrence of a changeover */
1040                char changeover_active;
1041
1042                /* A flag which indicates whether the change of primary is
1043                 * the first switch to this destination address during an
1044                 * active switch.
1045                 */
1046                char cycling_changeover;
1047
1048                /* A temporary flag, which is used during the processing of
1049                 * a SACK to estimate the causative TSN(s)'s group.
1050                 */
1051                char cacc_saw_newack;
1052        } cacc;
1053
1054        /* 64-bit random number sent with heartbeat. */
1055        __u64 hb_nonce;
1056};
1057
1058struct sctp_transport *sctp_transport_new(const union sctp_addr *,
1059                                          gfp_t);
1060void sctp_transport_set_owner(struct sctp_transport *,
1061                              struct sctp_association *);
1062void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
1063                          struct sctp_sock *);
1064void sctp_transport_pmtu(struct sctp_transport *);
1065void sctp_transport_free(struct sctp_transport *);
1066void sctp_transport_reset_timers(struct sctp_transport *, int);
1067void sctp_transport_hold(struct sctp_transport *);
1068void sctp_transport_put(struct sctp_transport *);
1069void sctp_transport_update_rto(struct sctp_transport *, __u32);
1070void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
1071void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t);
1072unsigned long sctp_transport_timeout(struct sctp_transport *);
1073void sctp_transport_reset(struct sctp_transport *);
1074void sctp_transport_update_pmtu(struct sctp_transport *, u32);
1075
1076
1077/* This is the structure we use to queue packets as they come into
1078 * SCTP.  We write packets to it and read chunks from it.
1079 */
1080struct sctp_inq {
1081        /* This is actually a queue of sctp_chunk each
1082         * containing a partially decoded packet.
1083         */
1084        struct list_head in_chunk_list;
1085        /* This is the packet which is currently off the in queue and is
1086         * being worked on through the inbound chunk processing.
1087         */
1088        struct sctp_chunk *in_progress;
1089
1090        /* This is the delayed task to finish delivering inbound
1091         * messages.
1092         */
1093        struct work_struct immediate;
1094
1095        int malloced;        /* Is this structure kfree()able?  */
1096};
1097
1098void sctp_inq_init(struct sctp_inq *);
1099void sctp_inq_free(struct sctp_inq *);
1100void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
1101struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
1102struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *);
1103void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t);
1104
1105/* This is the structure we use to hold outbound chunks.  You push
1106 * chunks in and they automatically pop out the other end as bundled
1107 * packets (it calls (*output_handler)()).
1108 *
1109 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1110 * and 8.2 of the v13 draft.
1111 *
1112 * It handles retransmissions.  The connection to the timeout portion
1113 * of the state machine is through sctp_..._timeout() and timeout_handler.
1114 *
1115 * If you feed it SACKs, it will eat them.
1116 *
1117 * If you give it big chunks, it will fragment them.
1118 *
1119 * It assigns TSN's to data chunks.  This happens at the last possible
1120 * instant before transmission.
1121 *
1122 * When free()'d, it empties itself out via output_handler().
1123 */
1124struct sctp_outq {
1125        struct sctp_association *asoc;
1126
1127        /* Data pending that has never been transmitted.  */
1128        struct list_head out_chunk_list;
1129
1130        unsigned out_qlen;      /* Total length of queued data chunks. */
1131
1132        /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1133        unsigned error;
1134
1135        /* These are control chunks we want to send.  */
1136        struct list_head control_chunk_list;
1137
1138        /* These are chunks that have been sacked but are above the
1139         * CTSN, or cumulative tsn ack point.
1140         */
1141        struct list_head sacked;
1142
1143        /* Put chunks on this list to schedule them for
1144         * retransmission.
1145         */
1146        struct list_head retransmit;
1147
1148        /* Put chunks on this list to save them for FWD TSN processing as
1149         * they were abandoned.
1150         */
1151        struct list_head abandoned;
1152
1153        /* How many unackd bytes do we have in-flight?  */
1154        __u32 outstanding_bytes;
1155
1156        /* Are we doing fast-rtx on this queue */
1157        char fast_rtx;
1158
1159        /* Corked? */
1160        char cork;
1161
1162        /* Is this structure empty?  */
1163        char empty;
1164
1165        /* Are we kfree()able? */
1166        char malloced;
1167};
1168
1169void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1170void sctp_outq_teardown(struct sctp_outq *);
1171void sctp_outq_free(struct sctp_outq*);
1172int sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk);
1173int sctp_outq_sack(struct sctp_outq *, struct sctp_sackhdr *);
1174int sctp_outq_is_empty(const struct sctp_outq *);
1175void sctp_outq_restart(struct sctp_outq *);
1176
1177void sctp_retransmit(struct sctp_outq *, struct sctp_transport *,
1178                     sctp_retransmit_reason_t);
1179void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1180int sctp_outq_uncork(struct sctp_outq *);
1181/* Uncork and flush an outqueue.  */
1182static inline void sctp_outq_cork(struct sctp_outq *q)
1183{
1184        q->cork = 1;
1185}
1186
1187/* These bind address data fields common between endpoints and associations */
1188struct sctp_bind_addr {
1189
1190        /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1191         *
1192         * SCTP Port:   The local SCTP port number the endpoint is
1193         *              bound to.
1194         */
1195        __u16 port;
1196
1197        /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1198         *
1199         * Address List: The list of IP addresses that this instance
1200         *      has bound.  This information is passed to one's
1201         *      peer(s) in INIT and INIT ACK chunks.
1202         */
1203        struct list_head address_list;
1204
1205        int malloced;        /* Are we kfree()able?  */
1206};
1207
1208void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1209void sctp_bind_addr_free(struct sctp_bind_addr *);
1210int sctp_bind_addr_copy(struct sctp_bind_addr *dest,
1211                        const struct sctp_bind_addr *src,
1212                        sctp_scope_t scope, gfp_t gfp,
1213                        int flags);
1214int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
1215                        const struct sctp_bind_addr *src,
1216                        gfp_t gfp);
1217int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1218                       __u8 addr_state, gfp_t gfp);
1219int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1220int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1221                         struct sctp_sock *);
1222int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *,
1223                         struct sctp_sock *, struct sctp_sock *);
1224int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
1225                         const union sctp_addr *addr);
1226union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr   *bp,
1227                                        const union sctp_addr   *addrs,
1228                                        int                     addrcnt,
1229                                        struct sctp_sock        *opt);
1230union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1231                                         int *addrs_len,
1232                                         gfp_t gfp);
1233int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1234                           __u16 port, gfp_t gfp);
1235
1236sctp_scope_t sctp_scope(const union sctp_addr *);
1237int sctp_in_scope(const union sctp_addr *addr, const sctp_scope_t scope);
1238int sctp_is_any(struct sock *sk, const union sctp_addr *addr);
1239int sctp_addr_is_valid(const union sctp_addr *addr);
1240
1241
1242/* What type of endpoint?  */
1243typedef enum {
1244        SCTP_EP_TYPE_SOCKET,
1245        SCTP_EP_TYPE_ASSOCIATION,
1246} sctp_endpoint_type_t;
1247
1248/*
1249 * A common base class to bridge the implmentation view of a
1250 * socket (usually listening) endpoint versus an association's
1251 * local endpoint.
1252 * This common structure is useful for several purposes:
1253 *   1) Common interface for lookup routines.
1254 *      a) Subfunctions work for either endpoint or association
1255 *      b) Single interface to lookup allows hiding the lookup lock rather
1256 *         than acquiring it externally.
1257 *   2) Common interface for the inbound chunk handling/state machine.
1258 *   3) Common object handling routines for reference counting, etc.
1259 *   4) Disentangle association lookup from endpoint lookup, where we
1260 *      do not have to find our endpoint to find our association.
1261 *
1262 */
1263
1264struct sctp_ep_common {
1265        /* Fields to help us manage our entries in the hash tables. */
1266        struct hlist_node node;
1267        int hashent;
1268
1269        /* Runtime type information.  What kind of endpoint is this? */
1270        sctp_endpoint_type_t type;
1271
1272        /* Some fields to help us manage this object.
1273         *   refcnt   - Reference count access to this object.
1274         *   dead     - Do not attempt to use this object.
1275         *   malloced - Do we need to kfree this object?
1276         */
1277        atomic_t    refcnt;
1278        char        dead;
1279        char        malloced;
1280
1281        /* What socket does this endpoint belong to?  */
1282        struct sock *sk;
1283
1284        /* This is where we receive inbound chunks.  */
1285        struct sctp_inq   inqueue;
1286
1287        /* This substructure includes the defining parameters of the
1288         * endpoint:
1289         * bind_addr.port is our shared port number.
1290         * bind_addr.address_list is our set of local IP addresses.
1291         */
1292        struct sctp_bind_addr bind_addr;
1293};
1294
1295
1296/* RFC Section 1.4 Key Terms
1297 *
1298 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1299 *   multi-homed host, an SCTP endpoint is represented to its peers as a
1300 *   combination of a set of eligible destination transport addresses to
1301 *   which SCTP packets can be sent and a set of eligible source
1302 *   transport addresses from which SCTP packets can be received.
1303 *   All transport addresses used by an SCTP endpoint must use the
1304 *   same port number, but can use multiple IP addresses. A transport
1305 *   address used by an SCTP endpoint must not be used by another
1306 *   SCTP endpoint. In other words, a transport address is unique
1307 *   to an SCTP endpoint.
1308 *
1309 * From an implementation perspective, each socket has one of these.
1310 * A TCP-style socket will have exactly one association on one of
1311 * these.  An UDP-style socket will have multiple associations hanging
1312 * off one of these.
1313 */
1314
1315struct sctp_endpoint {
1316        /* Common substructure for endpoint and association. */
1317        struct sctp_ep_common base;
1318
1319        /* Associations: A list of current associations and mappings
1320         *            to the data consumers for each association. This
1321         *            may be in the form of a hash table or other
1322         *            implementation dependent structure. The data
1323         *            consumers may be process identification
1324         *            information such as file descriptors, named pipe
1325         *            pointer, or table pointers dependent on how SCTP
1326         *            is implemented.
1327         */
1328        /* This is really a list of struct sctp_association entries. */
1329        struct list_head asocs;
1330
1331        /* Secret Key: A secret key used by this endpoint to compute
1332         *            the MAC.  This SHOULD be a cryptographic quality
1333         *            random number with a sufficient length.
1334         *            Discussion in [RFC1750] can be helpful in
1335         *            selection of the key.
1336         */
1337        __u8 secret_key[SCTP_HOW_MANY_SECRETS][SCTP_SECRET_SIZE];
1338        int current_key;
1339        int last_key;
1340        int key_changed_at;
1341
1342        /* digest:  This is a digest of the sctp cookie.  This field is
1343         *          only used on the receive path when we try to validate
1344         *          that the cookie has not been tampered with.  We put
1345         *          this here so we pre-allocate this once and can re-use
1346         *          on every receive.
1347         */
1348        __u8 *digest;
1349 
1350        /* sendbuf acct. policy.        */
1351        __u32 sndbuf_policy;
1352
1353        /* rcvbuf acct. policy. */
1354        __u32 rcvbuf_policy;
1355
1356        /* SCTP AUTH: array of the HMACs that will be allocated
1357         * we need this per association so that we don't serialize
1358         */
1359        struct crypto_hash **auth_hmacs;
1360
1361        /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1362         struct sctp_hmac_algo_param *auth_hmacs_list;
1363
1364        /* SCTP-AUTH: chunks to authenticate encoded into parameter */
1365        struct sctp_chunks_param *auth_chunk_list;
1366
1367        /* SCTP-AUTH: endpoint shared keys */
1368        struct list_head endpoint_shared_keys;
1369        __u16 active_key_id;
1370};
1371
1372/* Recover the outter endpoint structure. */
1373static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1374{
1375        struct sctp_endpoint *ep;
1376
1377        ep = container_of(base, struct sctp_endpoint, base);
1378        return ep;
1379}
1380
1381/* These are function signatures for manipulating endpoints.  */
1382struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1383void sctp_endpoint_free(struct sctp_endpoint *);
1384void sctp_endpoint_put(struct sctp_endpoint *);
1385void sctp_endpoint_hold(struct sctp_endpoint *);
1386void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1387struct sctp_association *sctp_endpoint_lookup_assoc(
1388        const struct sctp_endpoint *ep,
1389        const union sctp_addr *paddr,
1390        struct sctp_transport **);
1391int sctp_endpoint_is_peeled_off(struct sctp_endpoint *,
1392                                const union sctp_addr *);
1393struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1394                                        const union sctp_addr *);
1395int sctp_has_association(const union sctp_addr *laddr,
1396                         const union sctp_addr *paddr);
1397
1398int sctp_verify_init(const struct sctp_association *asoc, sctp_cid_t,
1399                     sctp_init_chunk_t *peer_init, struct sctp_chunk *chunk,
1400                     struct sctp_chunk **err_chunk);
1401int sctp_process_init(struct sctp_association *, sctp_cid_t cid,
1402                      const union sctp_addr *peer,
1403                      sctp_init_chunk_t *init, gfp_t gfp);
1404__u32 sctp_generate_tag(const struct sctp_endpoint *);
1405__u32 sctp_generate_tsn(const struct sctp_endpoint *);
1406
1407struct sctp_inithdr_host {
1408        __u32 init_tag;
1409        __u32 a_rwnd;
1410        __u16 num_outbound_streams;
1411        __u16 num_inbound_streams;
1412        __u32 initial_tsn;
1413};
1414
1415/* RFC2960
1416 *
1417 * 12. Recommended Transmission Control Block (TCB) Parameters
1418 *
1419 * This section details a recommended set of parameters that should
1420 * be contained within the TCB for an implementation. This section is
1421 * for illustrative purposes and should not be deemed as requirements
1422 * on an implementation or as an exhaustive list of all parameters
1423 * inside an SCTP TCB. Each implementation may need its own additional
1424 * parameters for optimization.
1425 */
1426
1427
1428/* Here we have information about each individual association. */
1429struct sctp_association {
1430
1431        /* A base structure common to endpoint and association.
1432         * In this context, it represents the associations's view
1433         * of the local endpoint of the association.
1434         */
1435        struct sctp_ep_common base;
1436
1437        /* Associations on the same socket. */
1438        struct list_head asocs;
1439
1440        /* association id. */
1441        sctp_assoc_t assoc_id;
1442
1443        /* This is our parent endpoint.  */
1444        struct sctp_endpoint *ep;
1445
1446        /* These are those association elements needed in the cookie.  */
1447        struct sctp_cookie c;
1448
1449        /* This is all information about our peer.  */
1450        struct {
1451                /* rwnd
1452                 *
1453                 * Peer Rwnd   : Current calculated value of the peer's rwnd.
1454                 */
1455                __u32 rwnd;
1456
1457                /* transport_addr_list
1458                 *
1459                 * Peer        : A list of SCTP transport addresses that the
1460                 * Transport   : peer is bound to. This information is derived
1461                 * Address     : from the INIT or INIT ACK and is used to
1462                 * List        : associate an inbound packet with a given
1463                 *             : association. Normally this information is
1464                 *             : hashed or keyed for quick lookup and access
1465                 *             : of the TCB.
1466                 *             : The list is also initialized with the list
1467                 *             : of addresses passed with the sctp_connectx()
1468                 *             : call.
1469                 *
1470                 * It is a list of SCTP_transport's.
1471                 */
1472                struct list_head transport_addr_list;
1473
1474                /* transport_count
1475                 *
1476                 * Peer        : A count of the number of peer addresses
1477                 * Transport   : in the Peer Transport Address List.
1478                 * Address     :
1479                 * Count       :
1480                 */
1481                __u16 transport_count;
1482
1483                /* port
1484                 *   The transport layer port number.
1485                 */
1486                __u16 port;
1487
1488                /* primary_path
1489                 *
1490                 * Primary     : This is the current primary destination
1491                 * Path        : transport address of the peer endpoint.  It
1492                 *             : may also specify a source transport address
1493                 *             : on this endpoint.
1494                 *
1495                 * All of these paths live on transport_addr_list.
1496                 *
1497                 * At the bakeoffs, we discovered that the intent of
1498                 * primaryPath is that it only changes when the ULP
1499                 * asks to have it changed.  We add the activePath to
1500                 * designate the connection we are currently using to
1501                 * transmit new data and most control chunks.
1502                 */
1503                struct sctp_transport *primary_path;
1504
1505                /* Cache the primary path address here, when we
1506                 * need a an address for msg_name.
1507                 */
1508                union sctp_addr primary_addr;
1509
1510                /* active_path
1511                 *   The path that we are currently using to
1512                 *   transmit new data and most control chunks.
1513                 */
1514                struct sctp_transport *active_path;
1515
1516                /* retran_path
1517                 *
1518                 * RFC2960 6.4 Multi-homed SCTP Endpoints
1519                 * ...
1520                 * Furthermore, when its peer is multi-homed, an
1521                 * endpoint SHOULD try to retransmit a chunk to an
1522                 * active destination transport address that is
1523                 * different from the last destination address to
1524                 * which the DATA chunk was sent.
1525                 */
1526                struct sctp_transport *retran_path;
1527
1528                /* Pointer to last transport I have sent on.  */
1529                struct sctp_transport *last_sent_to;
1530
1531                /* This is the last transport I have received DATA on.  */
1532                struct sctp_transport *last_data_from;
1533
1534                /*
1535                 * Mapping  An array of bits or bytes indicating which out of
1536                 * Array    order TSN's have been received (relative to the
1537                 *          Last Rcvd TSN). If no gaps exist, i.e. no out of
1538                 *          order packets have been received, this array
1539                 *          will be set to all zero. This structure may be
1540                 *          in the form of a circular buffer or bit array.
1541                 *
1542                 * Last Rcvd   : This is the last TSN received in
1543                 * TSN         : sequence. This value is set initially by
1544                 *             : taking the peer's Initial TSN, received in
1545                 *             : the INIT or INIT ACK chunk, and subtracting
1546                 *             : one from it.
1547                 *
1548                 * Throughout most of the specification this is called the
1549                 * "Cumulative TSN ACK Point".  In this case, we
1550                 * ignore the advice in 12.2 in favour of the term
1551                 * used in the bulk of the text.  This value is hidden
1552                 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1553                 */
1554                struct sctp_tsnmap tsn_map;
1555
1556                /* Ack State   : This flag indicates if the next received
1557                 *             : packet is to be responded to with a
1558                 *             : SACK. This is initializedto 0.  When a packet
1559                 *             : is received it is incremented. If this value
1560                 *             : reaches 2 or more, a SACK is sent and the
1561                 *             : value is reset to 0. Note: This is used only
1562                 *             : when no DATA chunks are received out of
1563                 *             : order.  When DATA chunks are out of order,
1564                 *             : SACK's are not delayed (see Section 6).
1565                 */
1566                __u8    sack_needed;     /* Do we need to sack the peer? */
1567                __u32   sack_cnt;
1568
1569                /* These are capabilities which our peer advertised.  */
1570                __u8    ecn_capable:1,      /* Can peer do ECN? */
1571                        ipv4_address:1,     /* Peer understands IPv4 addresses? */
1572                        ipv6_address:1,     /* Peer understands IPv6 addresses? */
1573                        hostname_address:1, /* Peer understands DNS addresses? */
1574                        asconf_capable:1,   /* Does peer support ADDIP? */
1575                        prsctp_capable:1,   /* Can peer do PR-SCTP? */
1576                        auth_capable:1;     /* Is peer doing SCTP-AUTH? */
1577
1578                __u32   adaptation_ind;  /* Adaptation Code point. */
1579
1580                /* This mask is used to disable sending the ASCONF chunk
1581                 * with specified parameter to peer.
1582                 */
1583                __be16 addip_disabled_mask;
1584
1585                struct sctp_inithdr_host i;
1586                int cookie_len;
1587                void *cookie;
1588
1589                /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1590                 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1591                 * Initial TSN Value minus 1
1592                 */
1593                __u32 addip_serial;
1594
1595                /* SCTP-AUTH: We need to know pears random number, hmac list
1596                 * and authenticated chunk list.  All that is part of the
1597                 * cookie and these are just pointers to those locations
1598                 */
1599                sctp_random_param_t *peer_random;
1600                sctp_chunks_param_t *peer_chunks;
1601                sctp_hmac_algo_param_t *peer_hmacs;
1602        } peer;
1603
1604        /* State       : A state variable indicating what state the
1605         *             : association is in, i.e. COOKIE-WAIT,
1606         *             : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1607         *             : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1608         *
1609         *              Note: No "CLOSED" state is illustrated since if a
1610         *              association is "CLOSED" its TCB SHOULD be removed.
1611         *
1612         *              In this implementation we DO have a CLOSED
1613         *              state which is used during initiation and shutdown.
1614         *
1615         *              State takes values from SCTP_STATE_*.
1616         */
1617        sctp_state_t state;
1618
1619        /* The cookie life I award for any cookie.  */
1620        struct timeval cookie_life;
1621
1622        /* Overall     : The overall association error count.
1623         * Error Count : [Clear this any time I get something.]
1624         */
1625        int overall_error_count;
1626
1627        /* These are the association's initial, max, and min RTO values.
1628         * These values will be initialized by system defaults, but can
1629         * be modified via the SCTP_RTOINFO socket option.
1630         */
1631        unsigned long rto_initial;
1632        unsigned long rto_max;
1633        unsigned long rto_min;
1634
1635        /* Maximum number of new data packets that can be sent in a burst.  */
1636        int max_burst;
1637
1638        /* This is the max_retrans value for the association.  This value will
1639         * be initialized initialized from system defaults, but can be
1640         * modified by the SCTP_ASSOCINFO socket option.
1641         */
1642        int max_retrans;
1643
1644        /* Maximum number of times the endpoint will retransmit INIT  */
1645        __u16 max_init_attempts;
1646
1647        /* How many times have we resent an INIT? */
1648        __u16 init_retries;
1649
1650        /* The largest timeout or RTO value to use in attempting an INIT */
1651        unsigned long max_init_timeo;
1652
1653        /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1654         * the destination address every heartbeat interval. This value
1655         * will be inherited by all new transports.
1656         */
1657        unsigned long hbinterval;
1658
1659        /* This is the max_retrans value for new transports in the
1660         * association.
1661         */
1662        __u16 pathmaxrxt;
1663
1664        /* Flag that path mtu update is pending */
1665        __u8   pmtu_pending;
1666
1667        /* Association : The smallest PMTU discovered for all of the
1668         * PMTU        : peer's transport addresses.
1669         */
1670        __u32 pathmtu;
1671
1672        /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1673        __u32 param_flags;
1674
1675        /* SACK delay timeout */
1676        unsigned long sackdelay;
1677        __u32 sackfreq;
1678
1679
1680        unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES];
1681        struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1682
1683        /* Transport to which SHUTDOWN chunk was last sent.  */
1684        struct sctp_transport *shutdown_last_sent_to;
1685
1686        /* How many times have we resent a SHUTDOWN */
1687        int shutdown_retries;
1688
1689        /* Transport to which INIT chunk was last sent.  */
1690        struct sctp_transport *init_last_sent_to;
1691
1692        /* Next TSN    : The next TSN number to be assigned to a new
1693         *             : DATA chunk.  This is sent in the INIT or INIT
1694         *             : ACK chunk to the peer and incremented each
1695         *             : time a DATA chunk is assigned a TSN
1696         *             : (normally just prior to transmit or during
1697         *             : fragmentation).
1698         */
1699        __u32 next_tsn;
1700
1701        /*
1702         * Last Rcvd   : This is the last TSN received in sequence.  This value
1703         * TSN         : is set initially by taking the peer's Initial TSN,
1704         *             : received in the INIT or INIT ACK chunk, and
1705         *             : subtracting one from it.
1706         *
1707         * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1708         */
1709
1710        __u32 ctsn_ack_point;
1711
1712        /* PR-SCTP Advanced.Peer.Ack.Point */
1713        __u32 adv_peer_ack_point;
1714
1715        /* Highest TSN that is acknowledged by incoming SACKs. */
1716        __u32 highest_sacked;
1717
1718        /* The number of unacknowledged data chunks.  Reported through
1719         * the SCTP_STATUS sockopt.
1720         */
1721        __u16 unack_data;
1722
1723        /* The total number of data chunks that we've had to retransmit
1724         * as the result of a T3 timer expiration
1725         */
1726        __u32 rtx_data_chunks;
1727
1728        /* This is the association's receive buffer space.  This value is used
1729         * to set a_rwnd field in an INIT or a SACK chunk.
1730         */
1731        __u32 rwnd;
1732
1733        /* This is the last advertised value of rwnd over a SACK chunk. */
1734        __u32 a_rwnd;
1735
1736        /* Number of bytes by which the rwnd has slopped.  The rwnd is allowed
1737         * to slop over a maximum of the association's frag_point.
1738         */
1739        __u32 rwnd_over;
1740
1741        /* Keeps treack of rwnd pressure.  This happens when we have
1742         * a window, but not recevie buffer (i.e small packets).  This one
1743         * is releases slowly (1 PMTU at a time ).
1744         */
1745        __u32 rwnd_press;
1746
1747        /* This is the sndbuf size in use for the association.
1748         * This corresponds to the sndbuf size for the association,
1749         * as specified in the sk->sndbuf.
1750         */
1751        int sndbuf_used;
1752
1753        /* This is the amount of memory that this association has allocated
1754         * in the receive path at any given time.
1755         */
1756        atomic_t rmem_alloc;
1757
1758        /* This is the wait queue head for send requests waiting on
1759         * the association sndbuf space.
1760         */
1761        wait_queue_head_t       wait;
1762
1763        /* The message size at which SCTP fragmentation will occur. */
1764        __u32 frag_point;
1765        __u32 user_frag;
1766
1767        /* Counter used to count INIT errors. */
1768        int init_err_counter;
1769
1770        /* Count the number of INIT cycles (for doubling timeout). */
1771        int init_cycle;
1772
1773        /* Default send parameters. */
1774        __u16 default_stream;
1775        __u16 default_flags;
1776        __u32 default_ppid;
1777        __u32 default_context;
1778        __u32 default_timetolive;
1779
1780        /* Default receive parameters */
1781        __u32 default_rcv_context;
1782
1783        /* This tracks outbound ssn for a given stream.  */
1784        struct sctp_ssnmap *ssnmap;
1785
1786        /* All outbound chunks go through this structure.  */
1787        struct sctp_outq outqueue;
1788
1789        /* A smart pipe that will handle reordering and fragmentation,
1790         * as well as handle passing events up to the ULP.
1791         */
1792        struct sctp_ulpq ulpq;
1793
1794        /* Last TSN that caused an ECNE Chunk to be sent.  */
1795        __u32 last_ecne_tsn;
1796
1797        /* Last TSN that caused a CWR Chunk to be sent.  */
1798        __u32 last_cwr_tsn;
1799
1800        /* How many duplicated TSNs have we seen?  */
1801        int numduptsns;
1802
1803        /* Number of seconds of idle time before an association is closed.
1804         * In the association context, this is really used as a boolean
1805         * since the real timeout is stored in the timeouts array
1806         */
1807        __u32 autoclose;
1808
1809        /* These are to support
1810         * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1811         *  and Enforcement of Flow and Message Limits"
1812         * <draft-ietf-tsvwg-addip-sctp-02.txt>
1813         * or "ADDIP" for short.
1814         */
1815
1816
1817
1818        /* ADDIP Section 4.1.1 Congestion Control 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         * [This is our one-and-only-one ASCONF in flight.  If we do
1830         * not have an ASCONF in flight, this is NULL.]
1831         */
1832        struct sctp_chunk *addip_last_asconf;
1833
1834        /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
1835         *
1836         * This is needed to implement itmes E1 - E4 of the updated
1837         * spec.  Here is the justification:
1838         *
1839         * Since the peer may bundle multiple ASCONF chunks toward us,
1840         * we now need the ability to cache multiple ACKs.  The section
1841         * describes in detail how they are cached and cleaned up.
1842         */
1843        struct list_head asconf_ack_list;
1844
1845        /* These ASCONF chunks are waiting to be sent.
1846         *
1847         * These chunaks can't be pushed to outqueue until receiving
1848         * ASCONF_ACK for the previous ASCONF indicated by
1849         * addip_last_asconf, so as to guarantee that only one ASCONF
1850         * is in flight at any time.
1851         *
1852         * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1853         *
1854         * In defining the ASCONF Chunk transfer procedures, it is
1855         * essential that these transfers MUST NOT cause congestion
1856         * within the network.  To achieve this, we place these
1857         * restrictions on the transfer of ASCONF Chunks:
1858         *
1859         * R1) One and only one ASCONF Chunk MAY be in transit and
1860         * unacknowledged at any one time.  If a sender, after sending
1861         * an ASCONF chunk, decides it needs to transfer another
1862         * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1863         * returns from the previous ASCONF Chunk before sending a
1864         * subsequent ASCONF. Note this restriction binds each side,
1865         * so at any time two ASCONF may be in-transit on any given
1866         * association (one sent from each endpoint).
1867         *
1868         *
1869         * [I really think this is EXACTLY the sort of intelligence
1870         *  which already resides in sctp_outq.  Please move this
1871         *  queue and its supporting logic down there.  --piggy]
1872         */
1873        struct list_head addip_chunk_list;
1874
1875        /* ADDIP Section 4.1 ASCONF Chunk Procedures
1876         *
1877         * A2) A serial number should be assigned to the Chunk. The
1878         * serial number SHOULD be a monotonically increasing
1879         * number. The serial number SHOULD be initialized at
1880         * the start of the association to the same value as the
1881         * Initial TSN and every time a new ASCONF chunk is created
1882         * it is incremented by one after assigning the serial number
1883         * to the newly created chunk.
1884         *
1885         * ADDIP
1886         * 3.1.1  Address/Stream Configuration Change Chunk (ASCONF)
1887         *
1888         * Serial Number : 32 bits (unsigned integer)
1889         *
1890         * This value represents a Serial Number for the ASCONF
1891         * Chunk. The valid range of Serial Number is from 0 to
1892         * 4294967295 (2^32 - 1).  Serial Numbers wrap back to 0
1893         * after reaching 4294967295.
1894         */
1895        __u32 addip_serial;
1896
1897        /* SCTP AUTH: list of the endpoint shared keys.  These
1898         * keys are provided out of band by the user applicaton
1899         * and can't change during the lifetime of the association
1900         */
1901        struct list_head endpoint_shared_keys;
1902
1903        /* SCTP AUTH:
1904         * The current generated assocaition shared key (secret)
1905         */
1906        struct sctp_auth_bytes *asoc_shared_key;
1907
1908        /* SCTP AUTH: hmac id of the first peer requested algorithm
1909         * that we support.
1910         */
1911        __u16 default_hmac_id;
1912
1913        __u16 active_key_id;
1914
1915        __u8 need_ecne:1,       /* Need to send an ECNE Chunk? */
1916             temp:1;            /* Is it a temporary association? */
1917};
1918
1919
1920/* An eyecatcher for determining if we are really looking at an
1921 * association data structure.
1922 */
1923enum {
1924        SCTP_ASSOC_EYECATCHER = 0xa550c123,
1925};
1926
1927/* Recover the outter association structure. */
1928static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
1929{
1930        struct sctp_association *asoc;
1931
1932        asoc = container_of(base, struct sctp_association, base);
1933        return asoc;
1934}
1935
1936/* These are function signatures for manipulating associations.  */
1937
1938
1939struct sctp_association *
1940sctp_association_new(const struct sctp_endpoint *, const struct sock *,
1941                     sctp_scope_t scope, gfp_t gfp);
1942void sctp_association_free(struct sctp_association *);
1943void sctp_association_put(struct sctp_association *);
1944void sctp_association_hold(struct sctp_association *);
1945
1946struct sctp_transport *sctp_assoc_choose_alter_transport(
1947        struct sctp_association *, struct sctp_transport *);
1948void sctp_assoc_update_retran_path(struct sctp_association *);
1949struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
1950                                          const union sctp_addr *);
1951int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1952                            const union sctp_addr *laddr);
1953struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
1954                                     const union sctp_addr *address,
1955                                     const gfp_t gfp,
1956                                     const int peer_state);
1957void sctp_assoc_del_peer(struct sctp_association *asoc,
1958                         const union sctp_addr *addr);
1959void sctp_assoc_rm_peer(struct sctp_association *asoc,
1960                         struct sctp_transport *peer);
1961void sctp_assoc_control_transport(struct sctp_association *,
1962                                  struct sctp_transport *,
1963                                  sctp_transport_cmd_t, sctp_sn_error_t);
1964struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
1965struct sctp_transport *sctp_assoc_is_match(struct sctp_association *,
1966                                           const union sctp_addr *,
1967                                           const union sctp_addr *);
1968void sctp_assoc_migrate(struct sctp_association *, struct sock *);
1969void sctp_assoc_update(struct sctp_association *old,
1970                       struct sctp_association *new);
1971
1972__u32 sctp_association_get_next_tsn(struct sctp_association *);
1973
1974void sctp_assoc_sync_pmtu(struct sctp_association *);
1975void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned);
1976void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned);
1977void sctp_assoc_set_primary(struct sctp_association *,
1978                            struct sctp_transport *);
1979void sctp_assoc_del_nonprimary_peers(struct sctp_association *,
1980                                    struct sctp_transport *);
1981int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *,
1982                                     sctp_scope_t, gfp_t);
1983int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
1984                                         struct sctp_cookie*,
1985                                         gfp_t gfp);
1986int sctp_assoc_set_id(struct sctp_association *, gfp_t);
1987void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc);
1988struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
1989                                        const struct sctp_association *asoc,
1990                                        __be32 serial);
1991
1992
1993int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1994                        const union sctp_addr *ss2);
1995struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
1996
1997/* A convenience structure to parse out SCTP specific CMSGs. */
1998typedef struct sctp_cmsgs {
1999        struct sctp_initmsg *init;
2000        struct sctp_sndrcvinfo *info;
2001} sctp_cmsgs_t;
2002
2003/* Structure for tracking memory objects */
2004typedef struct {
2005        char *label;
2006        atomic_t *counter;
2007} sctp_dbg_objcnt_entry_t;
2008
2009#endif /* __sctp_structs_h__ */
2010