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
  63/* A convenience structure for handling sockaddr structures.
  64 * We should wean ourselves off this.
  65 */
  66union sctp_addr {
  67	struct sockaddr_in v4;
  68	struct sockaddr_in6 v6;
  69	struct sockaddr sa;
  70};
  71
  72/* Forward declarations for data structures. */
  73struct sctp_globals;
  74struct sctp_endpoint;
  75struct sctp_association;
  76struct sctp_transport;
  77struct sctp_packet;
  78struct sctp_chunk;
  79struct sctp_inq;
  80struct sctp_outq;
  81struct sctp_bind_addr;
  82struct sctp_ulpq;
  83struct sctp_ep_common;
  84struct sctp_ssnmap;
  85struct crypto_shash;
  86
  87
  88#include <net/sctp/tsnmap.h>
  89#include <net/sctp/ulpevent.h>
  90#include <net/sctp/ulpqueue.h>
  91
  92/* Structures useful for managing bind/connect. */
  93
  94struct sctp_bind_bucket {
  95	unsigned short	port;
  96	unsigned short	fastreuse;
  97	struct hlist_node	node;
  98	struct hlist_head	owner;
  99	struct net	*net;
 100};
 101
 102struct sctp_bind_hashbucket {
 103	spinlock_t	lock;
 104	struct hlist_head	chain;
 105};
 106
 107/* Used for hashing all associations.  */
 108struct sctp_hashbucket {
 109	rwlock_t	lock;
 110	struct hlist_head	chain;
 111} __attribute__((__aligned__(8)));
 112
 113
 114/* The SCTP globals structure. */
 115extern struct sctp_globals {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 116	/* This is a list of groups of functions for each address
 117	 * family that we support.
 118	 */
 119	struct list_head address_families;
 120
 121	/* This is the hash of all endpoints. */
 
 122	struct sctp_hashbucket *ep_hashtable;
 
 
 
 
 
 123	/* This is the sctp port control hash.	*/
 
 124	struct sctp_bind_hashbucket *port_hashtable;
 125	/* This is the hash of all transports. */
 126	struct rhashtable transport_hashtable;
 127
 128	/* Sizes of above hashtables. */
 129	int ep_hashsize;
 130	int port_hashsize;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 131
 132	/* Default initialization values to be applied to new associations. */
 133	__u16 max_instreams;
 134	__u16 max_outstreams;
 
 
 
 
 
 
 
 
 
 
 
 135
 136	/* Flag to indicate whether computing and verifying checksum
 137	 * is disabled. */
 138        bool checksum_disable;
 
 
 
 
 
 139} sctp_globals;
 140
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 141#define sctp_max_instreams		(sctp_globals.max_instreams)
 142#define sctp_max_outstreams		(sctp_globals.max_outstreams)
 143#define sctp_address_families		(sctp_globals.address_families)
 144#define sctp_ep_hashsize		(sctp_globals.ep_hashsize)
 145#define sctp_ep_hashtable		(sctp_globals.ep_hashtable)
 
 
 146#define sctp_port_hashsize		(sctp_globals.port_hashsize)
 147#define sctp_port_hashtable		(sctp_globals.port_hashtable)
 148#define sctp_transport_hashtable	(sctp_globals.transport_hashtable)
 
 
 
 
 
 
 
 
 
 
 
 149#define sctp_checksum_disable		(sctp_globals.checksum_disable)
 
 150
 151/* SCTP Socket type: UDP or TCP style. */
 152typedef enum {
 153	SCTP_SOCKET_UDP = 0,
 154	SCTP_SOCKET_UDP_HIGH_BANDWIDTH,
 155	SCTP_SOCKET_TCP
 156} sctp_socket_type_t;
 157
 158/* Per socket SCTP information. */
 159struct sctp_sock {
 160	/* inet_sock has to be the first member of sctp_sock */
 161	struct inet_sock inet;
 162	/* What kind of a socket is this? */
 163	sctp_socket_type_t type;
 164
 165	/* PF_ family specific functions.  */
 166	struct sctp_pf *pf;
 167
 168	/* Access to HMAC transform. */
 169	struct crypto_shash *hmac;
 170	char *sctp_hmac_alg;
 171
 172	/* What is our base endpointer? */
 173	struct sctp_endpoint *ep;
 174
 175	struct sctp_bind_bucket *bind_hash;
 176	/* Various Socket Options.  */
 177	__u16 default_stream;
 178	__u32 default_ppid;
 179	__u16 default_flags;
 180	__u32 default_context;
 181	__u32 default_timetolive;
 182	__u32 default_rcv_context;
 183	int max_burst;
 184
 185	/* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
 186	 * the destination address every heartbeat interval. This value
 187	 * will be inherited by all new associations.
 188	 */
 189	__u32 hbinterval;
 190
 191	/* This is the max_retrans value for new associations. */
 192	__u16 pathmaxrxt;
 193
 194	/* The initial Path MTU to use for new associations. */
 195	__u32 pathmtu;
 196
 197	/* The default SACK delay timeout for new associations. */
 198	__u32 sackdelay;
 199	__u32 sackfreq;
 200
 201	/* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
 202	__u32 param_flags;
 203
 204	struct sctp_initmsg initmsg;
 205	struct sctp_rtoinfo rtoinfo;
 206	struct sctp_paddrparams paddrparam;
 207	struct sctp_event_subscribe subscribe;
 208	struct sctp_assocparams assocparams;
 209
 210	int user_frag;
 211
 212	__u32 autoclose;
 213	__u8 nodelay;
 214	__u8 disable_fragments;
 215	__u8 v4mapped;
 216	__u8 frag_interleave;
 217	__u32 adaptation_ind;
 218	__u32 pd_point;
 219	__u8 recvrcvinfo;
 220	__u8 recvnxtinfo;
 221
 222	atomic_t pd_mode;
 223	/* Receive to here while partial delivery is in effect. */
 224	struct sk_buff_head pd_lobby;
 225
 226	/* These must be the last fields, as they will skipped on copies,
 227	 * like on accept and peeloff operations
 228	 */
 229	struct list_head auto_asconf_list;
 230	int do_auto_asconf;
 231};
 232
 233static inline struct sctp_sock *sctp_sk(const struct sock *sk)
 234{
 235       return (struct sctp_sock *)sk;
 236}
 237
 238static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
 239{
 240       return (struct sock *)sp;
 241}
 242
 243#if IS_ENABLED(CONFIG_IPV6)
 244struct sctp6_sock {
 245       struct sctp_sock  sctp;
 246       struct ipv6_pinfo inet6;
 247};
 248#endif /* CONFIG_IPV6 */
 249
 250
 251/* This is our APPLICATION-SPECIFIC state cookie.
 252 * THIS IS NOT DICTATED BY THE SPECIFICATION.
 253 */
 254/* These are the parts of an association which we send in the cookie.
 255 * Most of these are straight out of:
 256 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
 257 *
 258 */
 259
 260struct sctp_cookie {
 261
 262	/* My	       : Tag expected in every inbound packet and sent
 263	 * Verification: in the INIT or INIT ACK chunk.
 264	 * Tag	       :
 265	 */
 266	__u32 my_vtag;
 267
 268	/* Peer's      : Tag expected in every outbound packet except
 269	 * Verification: in the INIT chunk.
 270	 * Tag	       :
 271	 */
 272	__u32 peer_vtag;
 273
 274	/* The rest of these are not from the spec, but really need to
 275	 * be in the cookie.
 276	 */
 277
 278	/* My Tie Tag  : Assist in discovering a restarting association. */
 279	__u32 my_ttag;
 280
 281	/* Peer's Tie Tag: Assist in discovering a restarting association. */
 282	__u32 peer_ttag;
 283
 284	/* When does this cookie expire? */
 285	ktime_t expiration;
 286
 287	/* Number of inbound/outbound streams which are set
 288	 * and negotiated during the INIT process.
 289	 */
 290	__u16 sinit_num_ostreams;
 291	__u16 sinit_max_instreams;
 292
 293	/* This is the first sequence number I used.  */
 294	__u32 initial_tsn;
 295
 296	/* This holds the originating address of the INIT packet.  */
 297	union sctp_addr peer_addr;
 298
 299	/* IG Section 2.35.3 
 300	 * Include the source port of the INIT-ACK
 301	 */
 302	__u16		my_port;
 303
 304	__u8 prsctp_capable;
 305
 306	/* Padding for future use */
 307	__u8 padding;  		
 308
 309	__u32 adaptation_ind;
 310
 311	__u8 auth_random[sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH];
 312	__u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2];
 313	__u8 auth_chunks[sizeof(sctp_paramhdr_t) + SCTP_AUTH_MAX_CHUNKS];
 314
 315	/* This is a shim for my peer's INIT packet, followed by
 316	 * a copy of the raw address list of the association.
 317	 * The length of the raw address list is saved in the
 318	 * raw_addr_list_len field, which will be used at the time when
 319	 * the association TCB is re-constructed from the cookie.
 320	 */
 321	__u32 raw_addr_list_len;
 322	struct sctp_init_chunk peer_init[0];
 323};
 324
 325
 326/* The format of our cookie that we send to our peer. */
 327struct sctp_signed_cookie {
 328	__u8 signature[SCTP_SECRET_SIZE];
 329	__u32 __pad;		/* force sctp_cookie alignment to 64 bits */
 330	struct sctp_cookie c;
 331} __packed;
 332
 333/* This is another convenience type to allocate memory for address
 334 * params for the maximum size and pass such structures around
 335 * internally.
 336 */
 337union sctp_addr_param {
 338	struct sctp_paramhdr p;
 339	struct sctp_ipv4addr_param v4;
 340	struct sctp_ipv6addr_param v6;
 341};
 342
 343/* A convenience type to allow walking through the various
 344 * parameters and avoid casting all over the place.
 345 */
 346union sctp_params {
 347	void *v;
 348	struct sctp_paramhdr *p;
 349	struct sctp_cookie_preserve_param *life;
 350	struct sctp_hostname_param *dns;
 351	struct sctp_cookie_param *cookie;
 352	struct sctp_supported_addrs_param *sat;
 353	struct sctp_ipv4addr_param *v4;
 354	struct sctp_ipv6addr_param *v6;
 355	union sctp_addr_param *addr;
 356	struct sctp_adaptation_ind_param *aind;
 357	struct sctp_supported_ext_param *ext;
 358	struct sctp_random_param *random;
 359	struct sctp_chunks_param *chunks;
 360	struct sctp_hmac_algo_param *hmac_algo;
 361	struct sctp_addip_param *addip;
 362};
 363
 364/* RFC 2960.  Section 3.3.5 Heartbeat.
 365 *    Heartbeat Information: variable length
 366 *    The Sender-specific Heartbeat Info field should normally include
 367 *    information about the sender's current time when this HEARTBEAT
 368 *    chunk is sent and the destination transport address to which this
 369 *    HEARTBEAT is sent (see Section 8.3).
 370 */
 371typedef struct sctp_sender_hb_info {
 372	struct sctp_paramhdr param_hdr;
 373	union sctp_addr daddr;
 374	unsigned long sent_at;
 375	__u64 hb_nonce;
 376} __packed sctp_sender_hb_info_t;
 377
 378/*
 379 *  RFC 2960 1.3.2 Sequenced Delivery within Streams
 380 *
 381 *  The term "stream" is used in SCTP to refer to a sequence of user
 382 *  messages that are to be delivered to the upper-layer protocol in
 383 *  order with respect to other messages within the same stream.  This is
 384 *  in contrast to its usage in TCP, where it refers to a sequence of
 385 *  bytes (in this document a byte is assumed to be eight bits).
 386 *  ...
 387 *
 388 *  This is the structure we use to track both our outbound and inbound
 389 *  SSN, or Stream Sequence Numbers.
 390 */
 391
 392struct sctp_stream {
 393	__u16 *ssn;
 394	unsigned int len;
 395};
 396
 397struct sctp_ssnmap {
 398	struct sctp_stream in;
 399	struct sctp_stream out;
 
 400};
 401
 402struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out,
 403				    gfp_t gfp);
 404void sctp_ssnmap_free(struct sctp_ssnmap *map);
 405void sctp_ssnmap_clear(struct sctp_ssnmap *map);
 406
 407/* What is the current SSN number for this stream? */
 408static inline __u16 sctp_ssn_peek(struct sctp_stream *stream, __u16 id)
 409{
 410	return stream->ssn[id];
 411}
 412
 413/* Return the next SSN number for this stream.	*/
 414static inline __u16 sctp_ssn_next(struct sctp_stream *stream, __u16 id)
 415{
 416	return stream->ssn[id]++;
 417}
 418
 419/* Skip over this ssn and all below. */
 420static inline void sctp_ssn_skip(struct sctp_stream *stream, __u16 id, 
 421				 __u16 ssn)
 422{
 423	stream->ssn[id] = ssn+1;
 424}
 425              
 426/*
 427 * Pointers to address related SCTP functions.
 428 * (i.e. things that depend on the address family.)
 429 */
 430struct sctp_af {
 431	int		(*sctp_xmit)	(struct sk_buff *skb,
 432					 struct sctp_transport *);
 433	int		(*setsockopt)	(struct sock *sk,
 434					 int level,
 435					 int optname,
 436					 char __user *optval,
 437					 unsigned int optlen);
 438	int		(*getsockopt)	(struct sock *sk,
 439					 int level,
 440					 int optname,
 441					 char __user *optval,
 442					 int __user *optlen);
 443	int		(*compat_setsockopt)	(struct sock *sk,
 444					 int level,
 445					 int optname,
 446					 char __user *optval,
 447					 unsigned int optlen);
 448	int		(*compat_getsockopt)	(struct sock *sk,
 449					 int level,
 450					 int optname,
 451					 char __user *optval,
 452					 int __user *optlen);
 453	void		(*get_dst)	(struct sctp_transport *t,
 454					 union sctp_addr *saddr,
 455					 struct flowi *fl,
 456					 struct sock *sk);
 457	void		(*get_saddr)	(struct sctp_sock *sk,
 458					 struct sctp_transport *t,
 459					 struct flowi *fl);
 460	void		(*copy_addrlist) (struct list_head *,
 461					  struct net_device *);
 462	int		(*cmp_addr)	(const union sctp_addr *addr1,
 463					 const union sctp_addr *addr2);
 464	void		(*addr_copy)	(union sctp_addr *dst,
 465					 union sctp_addr *src);
 466	void		(*from_skb)	(union sctp_addr *,
 467					 struct sk_buff *skb,
 468					 int saddr);
 469	void		(*from_sk)	(union sctp_addr *,
 470					 struct sock *sk);
 
 
 
 
 471	void		(*from_addr_param) (union sctp_addr *,
 472					    union sctp_addr_param *,
 473					    __be16 port, int iif);
 474	int		(*to_addr_param) (const union sctp_addr *,
 475					  union sctp_addr_param *); 
 476	int		(*addr_valid)	(union sctp_addr *,
 477					 struct sctp_sock *,
 478					 const struct sk_buff *);
 479	sctp_scope_t	(*scope) (union sctp_addr *);
 480	void		(*inaddr_any)	(union sctp_addr *, __be16);
 481	int		(*is_any)	(const union sctp_addr *);
 482	int		(*available)	(union sctp_addr *,
 483					 struct sctp_sock *);
 484	int		(*skb_iif)	(const struct sk_buff *sk);
 485	int		(*is_ce)	(const struct sk_buff *sk);
 486	void		(*seq_dump_addr)(struct seq_file *seq,
 487					 union sctp_addr *addr);
 488	void		(*ecn_capable)(struct sock *sk);
 489	__u16		net_header_len;
 490	int		sockaddr_len;
 491	sa_family_t	sa_family;
 492	struct list_head list;
 493};
 494
 495struct sctp_af *sctp_get_af_specific(sa_family_t);
 496int sctp_register_af(struct sctp_af *);
 497
 498/* Protocol family functions. */
 499struct sctp_pf {
 500	void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
 501	void (*skb_msgname)  (struct sk_buff *, char *, int *);
 502	int  (*af_supported) (sa_family_t, struct sctp_sock *);
 503	int  (*cmp_addr) (const union sctp_addr *,
 504			  const union sctp_addr *,
 505			  struct sctp_sock *);
 506	int  (*bind_verify) (struct sctp_sock *, union sctp_addr *);
 507	int  (*send_verify) (struct sctp_sock *, union sctp_addr *);
 508	int  (*supported_addrs)(const struct sctp_sock *, __be16 *);
 509	struct sock *(*create_accept_sk) (struct sock *sk,
 510					  struct sctp_association *asoc);
 511	int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr);
 512	void (*to_sk_saddr)(union sctp_addr *, struct sock *sk);
 513	void (*to_sk_daddr)(union sctp_addr *, struct sock *sk);
 514	struct sctp_af *af;
 515};
 516
 517
 518/* Structure to track chunk fragments that have been acked, but peer
 519 * fragments of the same message have not.
 520 */
 521struct sctp_datamsg {
 522	/* Chunks waiting to be submitted to lower layer. */
 523	struct list_head chunks;
 524	/* Reference counting. */
 525	atomic_t refcnt;
 526	/* When is this message no longer interesting to the peer? */
 527	unsigned long expires_at;
 528	/* Did the messenge fail to send? */
 529	int send_error;
 530	u8 send_failed:1,
 531	   can_abandon:1,   /* can chunks from this message can be abandoned. */
 532	   can_delay;	    /* should this message be Nagle delayed */
 533};
 534
 535struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
 536					    struct sctp_sndrcvinfo *,
 537					    struct iov_iter *);
 
 538void sctp_datamsg_put(struct sctp_datamsg *);
 539void sctp_chunk_fail(struct sctp_chunk *, int error);
 540int sctp_chunk_abandoned(struct sctp_chunk *);
 541
 542/* RFC2960 1.4 Key Terms
 543 *
 544 * o Chunk: A unit of information within an SCTP packet, consisting of
 545 * a chunk header and chunk-specific content.
 546 *
 547 * As a matter of convenience, we remember the SCTP common header for
 548 * each chunk as well as a few other header pointers...
 549 */
 550struct sctp_chunk {
 551	struct list_head list;
 552
 553	atomic_t refcnt;
 554
 555	/* This is our link to the per-transport transmitted list.  */
 556	struct list_head transmitted_list;
 557
 558	/* This field is used by chunks that hold fragmented data.
 559	 * For the first fragment this is the list that holds the rest of
 560	 * fragments. For the remaining fragments, this is the link to the
 561	 * frag_list maintained in the first fragment.
 562	 */
 563	struct list_head frag_list;
 564
 565	/* This points to the sk_buff containing the actual data.  */
 566	struct sk_buff *skb;
 567
 568	/* These are the SCTP headers by reverse order in a packet.
 569	 * Note that some of these may happen more than once.  In that
 570	 * case, we point at the "current" one, whatever that means
 571	 * for that level of header.
 572	 */
 573
 574	/* We point this at the FIRST TLV parameter to chunk_hdr.  */
 575	union sctp_params param_hdr;
 576	union {
 577		__u8 *v;
 578		struct sctp_datahdr *data_hdr;
 579		struct sctp_inithdr *init_hdr;
 580		struct sctp_sackhdr *sack_hdr;
 581		struct sctp_heartbeathdr *hb_hdr;
 582		struct sctp_sender_hb_info *hbs_hdr;
 583		struct sctp_shutdownhdr *shutdown_hdr;
 584		struct sctp_signed_cookie *cookie_hdr;
 585		struct sctp_ecnehdr *ecne_hdr;
 586		struct sctp_cwrhdr *ecn_cwr_hdr;
 587		struct sctp_errhdr *err_hdr;
 588		struct sctp_addiphdr *addip_hdr;
 589		struct sctp_fwdtsn_hdr *fwdtsn_hdr;
 590		struct sctp_authhdr *auth_hdr;
 591	} subh;
 592
 593	__u8 *chunk_end;
 594
 595	struct sctp_chunkhdr *chunk_hdr;
 596	struct sctphdr *sctp_hdr;
 597
 598	/* This needs to be recoverable for SCTP_SEND_FAILED events. */
 599	struct sctp_sndrcvinfo sinfo;
 600
 601	/* Which association does this belong to?  */
 602	struct sctp_association *asoc;
 603
 604	/* What endpoint received this chunk? */
 605	struct sctp_ep_common *rcvr;
 606
 607	/* We fill this in if we are calculating RTT. */
 608	unsigned long sent_at;
 609
 610	/* What is the origin IP address for this chunk?  */
 611	union sctp_addr source;
 612	/* Destination address for this chunk. */
 613	union sctp_addr dest;
 614
 615	/* For outbound message, track all fragments for SEND_FAILED. */
 616	struct sctp_datamsg *msg;
 617
 618	/* For an inbound chunk, this tells us where it came from.
 619	 * For an outbound chunk, it tells us where we'd like it to
 620	 * go.	It is NULL if we have no preference.
 621	 */
 622	struct sctp_transport *transport;
 623
 624	/* SCTP-AUTH:  For the special case inbound processing of COOKIE-ECHO
 625	 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
 626	 * spec violates the principle premis that all chunks are processed
 627	 * in order.
 628	 */
 629	struct sk_buff *auth_chunk;
 630
 631#define SCTP_CAN_FRTX 0x0
 632#define SCTP_NEED_FRTX 0x1
 633#define SCTP_DONT_FRTX 0x2
 634	__u16	rtt_in_progress:1,	/* This chunk used for RTT calc? */
 635		resent:1,		/* Has this chunk ever been resent. */
 636		has_tsn:1,		/* Does this chunk have a TSN yet? */
 637		has_ssn:1,		/* Does this chunk have a SSN yet? */
 638		singleton:1,		/* Only chunk in the packet? */
 639		end_of_packet:1,	/* Last chunk in the packet? */
 640		ecn_ce_done:1,		/* Have we processed the ECN CE bit? */
 641		pdiscard:1,		/* Discard the whole packet now? */
 642		tsn_gap_acked:1,	/* Is this chunk acked by a GAP ACK? */
 643		data_accepted:1,	/* At least 1 chunk accepted */
 644		auth:1,			/* IN: was auth'ed | OUT: needs auth */
 645		has_asconf:1,		/* IN: have seen an asconf before */
 646		tsn_missing_report:2,	/* Data chunk missing counter. */
 647		fast_retransmit:2;	/* Is this chunk fast retransmitted? */
 648};
 649
 650void sctp_chunk_hold(struct sctp_chunk *);
 651void sctp_chunk_put(struct sctp_chunk *);
 652int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len,
 653			  struct iov_iter *from);
 654void sctp_chunk_free(struct sctp_chunk *);
 655void  *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
 
 656struct sctp_chunk *sctp_chunkify(struct sk_buff *,
 657				 const struct sctp_association *,
 658				 struct sock *, gfp_t gfp);
 659void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
 660		     union sctp_addr *);
 661const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
 662
 663enum {
 664	SCTP_ADDR_NEW,		/* new address added to assoc/ep */
 665	SCTP_ADDR_SRC,		/* address can be used as source */
 666	SCTP_ADDR_DEL,		/* address about to be deleted */
 667};
 668
 669/* This is a structure for holding either an IPv6 or an IPv4 address.  */
 670struct sctp_sockaddr_entry {
 671	struct list_head list;
 672	struct rcu_head	rcu;
 673	union sctp_addr a;
 674	__u8 state;
 675	__u8 valid;
 676};
 677
 678#define SCTP_ADDRESS_TICK_DELAY	500
 679
 680typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *);
 681
 682/* This structure holds lists of chunks as we are assembling for
 683 * transmission.
 684 */
 685struct sctp_packet {
 686	/* These are the SCTP header values (host order) for the packet. */
 687	__u16 source_port;
 688	__u16 destination_port;
 689	__u32 vtag;
 690
 691	/* This contains the payload chunks.  */
 692	struct list_head chunk_list;
 693
 694	/* This is the overhead of the sctp and ip headers. */
 695	size_t overhead;
 696	/* This is the total size of all chunks INCLUDING padding.  */
 697	size_t size;
 698
 699	/* The packet is destined for this transport address.
 700	 * The function we finally use to pass down to the next lower
 701	 * layer lives in the transport structure.
 702	 */
 703	struct sctp_transport *transport;
 704
 705	/* pointer to the auth chunk for this packet */
 706	struct sctp_chunk *auth;
 707
 708	u8  has_cookie_echo:1,	/* This packet contains a COOKIE-ECHO chunk. */
 709	    has_sack:1,		/* This packet contains a SACK chunk. */
 710	    has_auth:1,		/* This packet contains an AUTH chunk */
 711	    has_data:1,		/* This packet contains at least 1 DATA chunk */
 712	    ipfragok:1;		/* So let ip fragment this packet */
 
 713};
 714
 715struct sctp_packet *sctp_packet_init(struct sctp_packet *,
 716				     struct sctp_transport *,
 717				     __u16 sport, __u16 dport);
 718struct sctp_packet *sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
 719sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *,
 720				       struct sctp_chunk *, int, gfp_t);
 721sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *,
 722                                     struct sctp_chunk *);
 723int sctp_packet_transmit(struct sctp_packet *, gfp_t);
 724void sctp_packet_free(struct sctp_packet *);
 725
 726static inline int sctp_packet_empty(struct sctp_packet *packet)
 727{
 728	return packet->size == packet->overhead;
 729}
 730
 731/* This represents a remote transport address.
 732 * For local transport addresses, we just use union sctp_addr.
 733 *
 734 * RFC2960 Section 1.4 Key Terms
 735 *
 736 *   o	Transport address:  A Transport Address is traditionally defined
 737 *	by Network Layer address, Transport Layer protocol and Transport
 738 *	Layer port number.  In the case of SCTP running over IP, a
 739 *	transport address is defined by the combination of an IP address
 740 *	and an SCTP port number (where SCTP is the Transport protocol).
 741 *
 742 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
 743 *
 744 *   o	The sender keeps a separate congestion control parameter set for
 745 *	each of the destination addresses it can send to (not each
 746 *	source-destination pair but for each destination).  The parameters
 747 *	should decay if the address is not used for a long enough time
 748 *	period.
 749 *
 750 */
 751struct sctp_transport {
 752	/* A list of transports. */
 753	struct list_head transports;
 754	struct rhash_head node;
 755
 756	/* Reference counting. */
 757	atomic_t refcnt;
 
 758		/* RTO-Pending : A flag used to track if one of the DATA
 759		 *		chunks sent to this address is currently being
 760		 *		used to compute a RTT. If this flag is 0,
 761		 *		the next DATA chunk sent to this destination
 762		 *		should be used to compute a RTT and this flag
 763		 *		should be set. Every time the RTT
 764		 *		calculation completes (i.e. the DATA chunk
 765		 *		is SACK'd) clear this flag.
 766		 */
 767	__u32	rto_pending:1,
 768
 769		/*
 770		 * hb_sent : a flag that signals that we have a pending
 771		 * heartbeat.
 772		 */
 773		hb_sent:1,
 774
 775		/* Is the Path MTU update pending on this tranport */
 776		pmtu_pending:1,
 777
 778		/* Has this transport moved the ctsn since we last sacked */
 779		sack_generation:1;
 780	u32 dst_cookie;
 781
 782	struct flowi fl;
 783
 784	/* This is the peer's IP address and port. */
 785	union sctp_addr ipaddr;
 786
 787	/* These are the functions we call to handle LLP stuff.	 */
 788	struct sctp_af *af_specific;
 789
 790	/* Which association do we belong to?  */
 791	struct sctp_association *asoc;
 792
 793	/* RFC2960
 794	 *
 795	 * 12.3 Per Transport Address Data
 796	 *
 797	 * For each destination transport address in the peer's
 798	 * address list derived from the INIT or INIT ACK chunk, a
 799	 * number of data elements needs to be maintained including:
 800	 */
 801	/* RTO	       : The current retransmission timeout value.  */
 802	unsigned long rto;
 803
 804	__u32 rtt;		/* This is the most recent RTT.	 */
 805
 806	/* RTTVAR      : The current RTT variation.  */
 807	__u32 rttvar;
 808
 809	/* SRTT	       : The current smoothed round trip time.	*/
 810	__u32 srtt;
 811
 812	/*
 813	 * These are the congestion stats.
 814	 */
 815	/* cwnd	       : The current congestion window.	 */
 816	__u32 cwnd;		  /* This is the actual cwnd.  */
 817
 818	/* ssthresh    : The current slow start threshold value.  */
 819	__u32 ssthresh;
 820
 821	/* partial     : The tracking method for increase of cwnd when in
 822	 * bytes acked : congestion avoidance mode (see Section 6.2.2)
 823	 */
 824	__u32 partial_bytes_acked;
 825
 826	/* Data that has been sent, but not acknowledged. */
 827	__u32 flight_size;
 828
 829	__u32 burst_limited;	/* Holds old cwnd when max.burst is applied */
 830
 831	/* Destination */
 832	struct dst_entry *dst;
 833	/* Source address. */
 834	union sctp_addr saddr;
 835
 836	/* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
 837	 * the destination address every heartbeat interval.
 838	 */
 839	unsigned long hbinterval;
 840
 841	/* SACK delay timeout */
 842	unsigned long sackdelay;
 843	__u32 sackfreq;
 844
 845	/* When was the last time that we heard from this transport? We use
 846	 * this to pick new active and retran paths.
 847	 */
 848	ktime_t last_time_heard;
 849
 850	/* When was the last time that we sent a chunk using this
 851	 * transport? We use this to check for idle transports
 852	 */
 853	unsigned long last_time_sent;
 854
 855	/* Last time(in jiffies) when cwnd is reduced due to the congestion
 856	 * indication based on ECNE chunk.
 857	 */
 858	unsigned long last_time_ecne_reduced;
 859
 860	/* This is the max_retrans value for the transport and will
 861	 * be initialized from the assocs value.  This can be changed
 862	 * using the SCTP_SET_PEER_ADDR_PARAMS socket option.
 863	 */
 864	__u16 pathmaxrxt;
 865
 866	/* This is the partially failed retrans value for the transport
 867	 * and will be initialized from the assocs value.  This can be changed
 868	 * using the SCTP_PEER_ADDR_THLDS socket option
 869	 */
 870	int pf_retrans;
 871	/* PMTU	      : The current known path MTU.  */
 872	__u32 pathmtu;
 873
 874	/* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
 875	__u32 param_flags;
 876
 877	/* The number of times INIT has been sent on this transport. */
 878	int init_sent_count;
 879
 880	/* state       : The current state of this destination,
 881	 *             : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
 882	 */
 883	int state;
 884
 885	/* These are the error stats for this destination.  */
 886
 887	/* Error count : The current error count for this destination.	*/
 888	unsigned short error_count;
 889
 890	/* Per	       : A timer used by each destination.
 891	 * Destination :
 892	 * Timer       :
 893	 *
 894	 * [Everywhere else in the text this is called T3-rtx. -ed]
 895	 */
 896	struct timer_list T3_rtx_timer;
 897
 898	/* Heartbeat timer is per destination. */
 899	struct timer_list hb_timer;
 900
 901	/* Timer to handle ICMP proto unreachable envets */
 902	struct timer_list proto_unreach_timer;
 903
 904	/* Since we're using per-destination retransmission timers
 905	 * (see above), we're also using per-destination "transmitted"
 906	 * queues.  This probably ought to be a private struct
 907	 * accessible only within the outqueue, but it's not, yet.
 908	 */
 909	struct list_head transmitted;
 910
 911	/* We build bundle-able packets for this transport here.  */
 912	struct sctp_packet packet;
 913
 914	/* This is the list of transports that have chunks to send.  */
 915	struct list_head send_ready;
 916
 917	/* State information saved for SFR_CACC algorithm. The key
 918	 * idea in SFR_CACC is to maintain state at the sender on a
 919	 * per-destination basis when a changeover happens.
 920	 *	char changeover_active;
 921	 *	char cycling_changeover;
 922	 *	__u32 next_tsn_at_change;
 923	 *	char cacc_saw_newack;
 924	 */
 925	struct {
 926		/* An unsigned integer, which stores the next TSN to be
 927		 * used by the sender, at the moment of changeover.
 928		 */
 929		__u32 next_tsn_at_change;
 930
 931		/* A flag which indicates the occurrence of a changeover */
 932		char changeover_active;
 933
 934		/* A flag which indicates whether the change of primary is
 935		 * the first switch to this destination address during an
 936		 * active switch.
 937		 */
 938		char cycling_changeover;
 939
 940		/* A temporary flag, which is used during the processing of
 941		 * a SACK to estimate the causative TSN(s)'s group.
 942		 */
 943		char cacc_saw_newack;
 944	} cacc;
 945
 946	/* 64-bit random number sent with heartbeat. */
 947	__u64 hb_nonce;
 948
 949	struct rcu_head rcu;
 950};
 951
 952struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *,
 953					  gfp_t);
 954void sctp_transport_set_owner(struct sctp_transport *,
 955			      struct sctp_association *);
 956void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
 957			  struct sctp_sock *);
 958void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk);
 959void sctp_transport_free(struct sctp_transport *);
 960void sctp_transport_reset_t3_rtx(struct sctp_transport *);
 961void sctp_transport_reset_hb_timer(struct sctp_transport *);
 962int sctp_transport_hold(struct sctp_transport *);
 963void sctp_transport_put(struct sctp_transport *);
 964void sctp_transport_update_rto(struct sctp_transport *, __u32);
 965void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
 966void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t);
 967void sctp_transport_burst_limited(struct sctp_transport *);
 968void sctp_transport_burst_reset(struct sctp_transport *);
 969unsigned long sctp_transport_timeout(struct sctp_transport *);
 970void sctp_transport_reset(struct sctp_transport *);
 971void sctp_transport_update_pmtu(struct sock *, struct sctp_transport *, u32);
 972void sctp_transport_immediate_rtx(struct sctp_transport *);
 973
 974
 975/* This is the structure we use to queue packets as they come into
 976 * SCTP.  We write packets to it and read chunks from it.
 977 */
 978struct sctp_inq {
 979	/* This is actually a queue of sctp_chunk each
 980	 * containing a partially decoded packet.
 981	 */
 982	struct list_head in_chunk_list;
 983	/* This is the packet which is currently off the in queue and is
 984	 * being worked on through the inbound chunk processing.
 985	 */
 986	struct sctp_chunk *in_progress;
 987
 988	/* This is the delayed task to finish delivering inbound
 989	 * messages.
 990	 */
 991	struct work_struct immediate;
 
 
 992};
 993
 994void sctp_inq_init(struct sctp_inq *);
 995void sctp_inq_free(struct sctp_inq *);
 996void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
 997struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
 998struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *);
 999void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t);
1000
1001/* This is the structure we use to hold outbound chunks.  You push
1002 * chunks in and they automatically pop out the other end as bundled
1003 * packets (it calls (*output_handler)()).
1004 *
1005 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1006 * and 8.2 of the v13 draft.
1007 *
1008 * It handles retransmissions.	The connection to the timeout portion
1009 * of the state machine is through sctp_..._timeout() and timeout_handler.
1010 *
1011 * If you feed it SACKs, it will eat them.
1012 *
1013 * If you give it big chunks, it will fragment them.
1014 *
1015 * It assigns TSN's to data chunks.  This happens at the last possible
1016 * instant before transmission.
1017 *
1018 * When free()'d, it empties itself out via output_handler().
1019 */
1020struct sctp_outq {
1021	struct sctp_association *asoc;
1022
1023	/* Data pending that has never been transmitted.  */
1024	struct list_head out_chunk_list;
1025
1026	unsigned int out_qlen;	/* Total length of queued data chunks. */
1027
1028	/* Error of send failed, may used in SCTP_SEND_FAILED event. */
1029	unsigned int error;
1030
1031	/* These are control chunks we want to send.  */
1032	struct list_head control_chunk_list;
1033
1034	/* These are chunks that have been sacked but are above the
1035	 * CTSN, or cumulative tsn ack point.
1036	 */
1037	struct list_head sacked;
1038
1039	/* Put chunks on this list to schedule them for
1040	 * retransmission.
1041	 */
1042	struct list_head retransmit;
1043
1044	/* Put chunks on this list to save them for FWD TSN processing as
1045	 * they were abandoned.
1046	 */
1047	struct list_head abandoned;
1048
1049	/* How many unackd bytes do we have in-flight?	*/
1050	__u32 outstanding_bytes;
1051
1052	/* Are we doing fast-rtx on this queue */
1053	char fast_rtx;
1054
1055	/* Corked? */
1056	char cork;
 
 
 
 
 
 
1057};
1058
1059void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1060void sctp_outq_teardown(struct sctp_outq *);
1061void sctp_outq_free(struct sctp_outq*);
1062int sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t);
1063int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *);
1064int sctp_outq_is_empty(const struct sctp_outq *);
1065void sctp_outq_restart(struct sctp_outq *);
1066
1067void sctp_retransmit(struct sctp_outq *, struct sctp_transport *,
1068		     sctp_retransmit_reason_t);
1069void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1070int sctp_outq_uncork(struct sctp_outq *, gfp_t gfp);
1071/* Uncork and flush an outqueue.  */
1072static inline void sctp_outq_cork(struct sctp_outq *q)
1073{
1074	q->cork = 1;
1075}
1076
1077/* These bind address data fields common between endpoints and associations */
1078struct sctp_bind_addr {
1079
1080	/* RFC 2960 12.1 Parameters necessary for the SCTP instance
1081	 *
1082	 * SCTP Port:	The local SCTP port number the endpoint is
1083	 *		bound to.
1084	 */
1085	__u16 port;
1086
1087	/* RFC 2960 12.1 Parameters necessary for the SCTP instance
1088	 *
1089	 * Address List: The list of IP addresses that this instance
1090	 *	has bound.  This information is passed to one's
1091	 *	peer(s) in INIT and INIT ACK chunks.
1092	 */
1093	struct list_head address_list;
 
 
1094};
1095
1096void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1097void sctp_bind_addr_free(struct sctp_bind_addr *);
1098int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest,
1099			const struct sctp_bind_addr *src,
1100			sctp_scope_t scope, gfp_t gfp,
1101			int flags);
1102int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
1103			const struct sctp_bind_addr *src,
1104			gfp_t gfp);
1105int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1106		       int new_size, __u8 addr_state, gfp_t gfp);
1107int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1108int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1109			 struct sctp_sock *);
1110int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *,
1111			 struct sctp_sock *, struct sctp_sock *);
1112int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
1113			 const union sctp_addr *addr);
1114union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr	*bp,
1115					const union sctp_addr	*addrs,
1116					int			addrcnt,
1117					struct sctp_sock	*opt);
1118union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1119					 int *addrs_len,
1120					 gfp_t gfp);
1121int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1122			   __u16 port, gfp_t gfp);
1123
1124sctp_scope_t sctp_scope(const union sctp_addr *);
1125int sctp_in_scope(struct net *net, const union sctp_addr *addr, const sctp_scope_t scope);
1126int sctp_is_any(struct sock *sk, const union sctp_addr *addr);
 
1127int sctp_is_ep_boundall(struct sock *sk);
1128
1129
1130/* What type of endpoint?  */
1131typedef enum {
1132	SCTP_EP_TYPE_SOCKET,
1133	SCTP_EP_TYPE_ASSOCIATION,
1134} sctp_endpoint_type_t;
1135
1136/*
1137 * A common base class to bridge the implmentation view of a
1138 * socket (usually listening) endpoint versus an association's
1139 * local endpoint.
1140 * This common structure is useful for several purposes:
1141 *   1) Common interface for lookup routines.
1142 *	a) Subfunctions work for either endpoint or association
1143 *	b) Single interface to lookup allows hiding the lookup lock rather
1144 *	   than acquiring it externally.
1145 *   2) Common interface for the inbound chunk handling/state machine.
1146 *   3) Common object handling routines for reference counting, etc.
1147 *   4) Disentangle association lookup from endpoint lookup, where we
1148 *	do not have to find our endpoint to find our association.
1149 *
1150 */
1151
1152struct sctp_ep_common {
1153	/* Fields to help us manage our entries in the hash tables. */
1154	struct hlist_node node;
1155	int hashent;
1156
1157	/* Runtime type information.  What kind of endpoint is this? */
1158	sctp_endpoint_type_t type;
1159
1160	/* Some fields to help us manage this object.
1161	 *   refcnt   - Reference count access to this object.
1162	 *   dead     - Do not attempt to use this object.
 
1163	 */
1164	atomic_t    refcnt;
1165	bool	    dead;
 
1166
1167	/* What socket does this endpoint belong to?  */
1168	struct sock *sk;
1169
1170	/* This is where we receive inbound chunks.  */
1171	struct sctp_inq	  inqueue;
1172
1173	/* This substructure includes the defining parameters of the
1174	 * endpoint:
1175	 * bind_addr.port is our shared port number.
1176	 * bind_addr.address_list is our set of local IP addresses.
1177	 */
1178	struct sctp_bind_addr bind_addr;
1179};
1180
1181
1182/* RFC Section 1.4 Key Terms
1183 *
1184 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1185 *   multi-homed host, an SCTP endpoint is represented to its peers as a
1186 *   combination of a set of eligible destination transport addresses to
1187 *   which SCTP packets can be sent and a set of eligible source
1188 *   transport addresses from which SCTP packets can be received.
1189 *   All transport addresses used by an SCTP endpoint must use the
1190 *   same port number, but can use multiple IP addresses. A transport
1191 *   address used by an SCTP endpoint must not be used by another
1192 *   SCTP endpoint. In other words, a transport address is unique
1193 *   to an SCTP endpoint.
1194 *
1195 * From an implementation perspective, each socket has one of these.
1196 * A TCP-style socket will have exactly one association on one of
1197 * these.  An UDP-style socket will have multiple associations hanging
1198 * off one of these.
1199 */
1200
1201struct sctp_endpoint {
1202	/* Common substructure for endpoint and association. */
1203	struct sctp_ep_common base;
1204
1205	/* Associations: A list of current associations and mappings
1206	 *	      to the data consumers for each association. This
1207	 *	      may be in the form of a hash table or other
1208	 *	      implementation dependent structure. The data
1209	 *	      consumers may be process identification
1210	 *	      information such as file descriptors, named pipe
1211	 *	      pointer, or table pointers dependent on how SCTP
1212	 *	      is implemented.
1213	 */
1214	/* This is really a list of struct sctp_association entries. */
1215	struct list_head asocs;
1216
1217	/* Secret Key: A secret key used by this endpoint to compute
1218	 *	      the MAC.	This SHOULD be a cryptographic quality
1219	 *	      random number with a sufficient length.
1220	 *	      Discussion in [RFC1750] can be helpful in
1221	 *	      selection of the key.
1222	 */
1223	__u8 secret_key[SCTP_SECRET_SIZE];
 
 
 
1224
1225 	/* digest:  This is a digest of the sctp cookie.  This field is
1226 	 * 	    only used on the receive path when we try to validate
1227 	 * 	    that the cookie has not been tampered with.  We put
1228 	 * 	    this here so we pre-allocate this once and can re-use
1229 	 * 	    on every receive.
1230 	 */
1231 	__u8 *digest;
1232 
1233	/* sendbuf acct. policy.	*/
1234	__u32 sndbuf_policy;
1235
1236	/* rcvbuf acct. policy.	*/
1237	__u32 rcvbuf_policy;
1238
1239	/* SCTP AUTH: array of the HMACs that will be allocated
1240	 * we need this per association so that we don't serialize
1241	 */
1242	struct crypto_shash **auth_hmacs;
1243
1244	/* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1245	 struct sctp_hmac_algo_param *auth_hmacs_list;
1246
1247	/* SCTP-AUTH: chunks to authenticate encoded into parameter */
1248	struct sctp_chunks_param *auth_chunk_list;
1249
1250	/* SCTP-AUTH: endpoint shared keys */
1251	struct list_head endpoint_shared_keys;
1252	__u16 active_key_id;
1253	__u8  auth_enable;
1254};
1255
1256/* Recover the outter endpoint structure. */
1257static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1258{
1259	struct sctp_endpoint *ep;
1260
1261	ep = container_of(base, struct sctp_endpoint, base);
1262	return ep;
1263}
1264
1265/* These are function signatures for manipulating endpoints.  */
1266struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1267void sctp_endpoint_free(struct sctp_endpoint *);
1268void sctp_endpoint_put(struct sctp_endpoint *);
1269void sctp_endpoint_hold(struct sctp_endpoint *);
1270void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1271struct sctp_association *sctp_endpoint_lookup_assoc(
1272	const struct sctp_endpoint *ep,
1273	const union sctp_addr *paddr,
1274	struct sctp_transport **);
1275int sctp_endpoint_is_peeled_off(struct sctp_endpoint *,
1276				const union sctp_addr *);
1277struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1278					struct net *, const union sctp_addr *);
1279int sctp_has_association(struct net *net, const union sctp_addr *laddr,
1280			 const union sctp_addr *paddr);
1281
1282int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep,
1283		     const struct sctp_association *asoc,
1284		     sctp_cid_t, sctp_init_chunk_t *peer_init,
1285		     struct sctp_chunk *chunk, struct sctp_chunk **err_chunk);
1286int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk,
1287		      const union sctp_addr *peer,
1288		      sctp_init_chunk_t *init, gfp_t gfp);
1289__u32 sctp_generate_tag(const struct sctp_endpoint *);
1290__u32 sctp_generate_tsn(const struct sctp_endpoint *);
1291
1292struct sctp_inithdr_host {
1293	__u32 init_tag;
1294	__u32 a_rwnd;
1295	__u16 num_outbound_streams;
1296	__u16 num_inbound_streams;
1297	__u32 initial_tsn;
1298};
1299
1300/* SCTP_GET_ASSOC_STATS counters */
1301struct sctp_priv_assoc_stats {
1302	/* Maximum observed rto in the association during subsequent
1303	 * observations. Value is set to 0 if no RTO measurement took place
1304	 * The transport where the max_rto was observed is returned in
1305	 * obs_rto_ipaddr
1306	 */
1307	struct sockaddr_storage obs_rto_ipaddr;
1308	__u64 max_obs_rto;
1309	/* Total In and Out SACKs received and sent */
1310	__u64 isacks;
1311	__u64 osacks;
1312	/* Total In and Out packets received and sent */
1313	__u64 opackets;
1314	__u64 ipackets;
1315	/* Total retransmitted chunks */
1316	__u64 rtxchunks;
1317	/* TSN received > next expected */
1318	__u64 outofseqtsns;
1319	/* Duplicate Chunks received */
1320	__u64 idupchunks;
1321	/* Gap Ack Blocks received */
1322	__u64 gapcnt;
1323	/* Unordered data chunks sent and received */
1324	__u64 ouodchunks;
1325	__u64 iuodchunks;
1326	/* Ordered data chunks sent and received */
1327	__u64 oodchunks;
1328	__u64 iodchunks;
1329	/* Control chunks sent and received */
1330	__u64 octrlchunks;
1331	__u64 ictrlchunks;
1332};
1333
1334/* RFC2960
1335 *
1336 * 12. Recommended Transmission Control Block (TCB) Parameters
1337 *
1338 * This section details a recommended set of parameters that should
1339 * be contained within the TCB for an implementation. This section is
1340 * for illustrative purposes and should not be deemed as requirements
1341 * on an implementation or as an exhaustive list of all parameters
1342 * inside an SCTP TCB. Each implementation may need its own additional
1343 * parameters for optimization.
1344 */
1345
1346
1347/* Here we have information about each individual association. */
1348struct sctp_association {
1349
1350	/* A base structure common to endpoint and association.
1351	 * In this context, it represents the associations's view
1352	 * of the local endpoint of the association.
1353	 */
1354	struct sctp_ep_common base;
1355
1356	/* Associations on the same socket. */
1357	struct list_head asocs;
1358
1359	/* association id. */
1360	sctp_assoc_t assoc_id;
1361
1362	/* This is our parent endpoint.	 */
1363	struct sctp_endpoint *ep;
1364
1365	/* These are those association elements needed in the cookie.  */
1366	struct sctp_cookie c;
1367
1368	/* This is all information about our peer.  */
1369	struct {
 
 
 
 
 
 
1370		/* transport_addr_list
1371		 *
1372		 * Peer	       : A list of SCTP transport addresses that the
1373		 * Transport   : peer is bound to. This information is derived
1374		 * Address     : from the INIT or INIT ACK and is used to
1375		 * List	       : associate an inbound packet with a given
1376		 *	       : association. Normally this information is
1377		 *	       : hashed or keyed for quick lookup and access
1378		 *	       : of the TCB.
1379		 *	       : The list is also initialized with the list
1380		 *	       : of addresses passed with the sctp_connectx()
1381		 *	       : call.
1382		 *
1383		 * It is a list of SCTP_transport's.
1384		 */
1385		struct list_head transport_addr_list;
1386
1387		/* rwnd
1388		 *
1389		 * Peer Rwnd   : Current calculated value of the peer's rwnd.
1390		 */
1391		__u32 rwnd;
1392
1393		/* transport_count
1394		 *
1395		 * Peer        : A count of the number of peer addresses
1396		 * Transport   : in the Peer Transport Address List.
1397		 * Address     :
1398		 * Count       :
1399		 */
1400		__u16 transport_count;
1401
1402		/* port
1403		 *   The transport layer port number.
1404		 */
1405		__u16 port;
1406
1407		/* primary_path
1408		 *
1409		 * Primary     : This is the current primary destination
1410		 * Path	       : transport address of the peer endpoint.  It
1411		 *	       : may also specify a source transport address
1412		 *	       : on this endpoint.
1413		 *
1414		 * All of these paths live on transport_addr_list.
1415		 *
1416		 * At the bakeoffs, we discovered that the intent of
1417		 * primaryPath is that it only changes when the ULP
1418		 * asks to have it changed.  We add the activePath to
1419		 * designate the connection we are currently using to
1420		 * transmit new data and most control chunks.
1421		 */
1422		struct sctp_transport *primary_path;
1423
1424		/* Cache the primary path address here, when we
1425		 * need a an address for msg_name.
1426		 */
1427		union sctp_addr primary_addr;
1428
1429		/* active_path
1430		 *   The path that we are currently using to
1431		 *   transmit new data and most control chunks.
1432		 */
1433		struct sctp_transport *active_path;
1434
1435		/* retran_path
1436		 *
1437		 * RFC2960 6.4 Multi-homed SCTP Endpoints
1438		 * ...
1439		 * Furthermore, when its peer is multi-homed, an
1440		 * endpoint SHOULD try to retransmit a chunk to an
1441		 * active destination transport address that is
1442		 * different from the last destination address to
1443		 * which the DATA chunk was sent.
1444		 */
1445		struct sctp_transport *retran_path;
1446
1447		/* Pointer to last transport I have sent on.  */
1448		struct sctp_transport *last_sent_to;
1449
1450		/* This is the last transport I have received DATA on.	*/
1451		struct sctp_transport *last_data_from;
1452
1453		/*
1454		 * Mapping  An array of bits or bytes indicating which out of
1455		 * Array    order TSN's have been received (relative to the
1456		 *	    Last Rcvd TSN). If no gaps exist, i.e. no out of
1457		 *	    order packets have been received, this array
1458		 *	    will be set to all zero. This structure may be
1459		 *	    in the form of a circular buffer or bit array.
1460		 *
1461		 * Last Rcvd   : This is the last TSN received in
1462		 * TSN	       : sequence. This value is set initially by
1463		 *	       : taking the peer's Initial TSN, received in
1464		 *	       : the INIT or INIT ACK chunk, and subtracting
1465		 *	       : one from it.
1466		 *
1467		 * Throughout most of the specification this is called the
1468		 * "Cumulative TSN ACK Point".	In this case, we
1469		 * ignore the advice in 12.2 in favour of the term
1470		 * used in the bulk of the text.  This value is hidden
1471		 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1472		 */
1473		struct sctp_tsnmap tsn_map;
1474
1475		/* This mask is used to disable sending the ASCONF chunk
1476		 * with specified parameter to peer.
1477		 */
1478		__be16 addip_disabled_mask;
1479
1480		/* These are capabilities which our peer advertised.  */
1481		__u8	ecn_capable:1,      /* Can peer do ECN? */
1482			ipv4_address:1,     /* Peer understands IPv4 addresses? */
1483			ipv6_address:1,     /* Peer understands IPv6 addresses? */
1484			hostname_address:1, /* Peer understands DNS addresses? */
1485			asconf_capable:1,   /* Does peer support ADDIP? */
1486			prsctp_capable:1,   /* Can peer do PR-SCTP? */
1487			auth_capable:1;     /* Is peer doing SCTP-AUTH? */
1488
1489		/* sack_needed : This flag indicates if the next received
1490		 *             : packet is to be responded to with a
1491		 *             : SACK. This is initialized to 0.  When a packet
1492		 *             : is received sack_cnt is incremented. If this value
1493		 *             : reaches 2 or more, a SACK is sent and the
1494		 *             : value is reset to 0. Note: This is used only
1495		 *             : when no DATA chunks are received out of
1496		 *             : order.  When DATA chunks are out of order,
1497		 *             : SACK's are not delayed (see Section 6).
1498		 */
1499		__u8    sack_needed:1,     /* Do we need to sack the peer? */
1500			sack_generation:1,
1501			zero_window_announced:1;
1502		__u32	sack_cnt;
1503
 
 
 
 
 
 
 
 
 
1504		__u32   adaptation_ind;	 /* Adaptation Code point. */
1505
 
 
 
 
 
1506		struct sctp_inithdr_host i;
1507		void *cookie;
1508		int cookie_len;
 
1509
1510		/* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1511		 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1512		 * Initial TSN Value minus 1
1513		 */
1514		__u32 addip_serial;
1515
1516		/* SCTP-AUTH: We need to know pears random number, hmac list
1517		 * and authenticated chunk list.  All that is part of the
1518		 * cookie and these are just pointers to those locations
1519		 */
1520		sctp_random_param_t *peer_random;
1521		sctp_chunks_param_t *peer_chunks;
1522		sctp_hmac_algo_param_t *peer_hmacs;
1523	} peer;
1524
1525	/* State       : A state variable indicating what state the
1526	 *	       : association is in, i.e. COOKIE-WAIT,
1527	 *	       : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1528	 *	       : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1529	 *
1530	 *		Note: No "CLOSED" state is illustrated since if a
1531	 *		association is "CLOSED" its TCB SHOULD be removed.
1532	 *
1533	 *		In this implementation we DO have a CLOSED
1534	 *		state which is used during initiation and shutdown.
1535	 *
1536	 *		State takes values from SCTP_STATE_*.
1537	 */
1538	sctp_state_t state;
1539
 
 
 
1540	/* Overall     : The overall association error count.
1541	 * Error Count : [Clear this any time I get something.]
1542	 */
1543	int overall_error_count;
1544
1545	/* The cookie life I award for any cookie.  */
1546	ktime_t cookie_life;
1547
1548	/* These are the association's initial, max, and min RTO values.
1549	 * These values will be initialized by system defaults, but can
1550	 * be modified via the SCTP_RTOINFO socket option.
1551	 */
1552	unsigned long rto_initial;
1553	unsigned long rto_max;
1554	unsigned long rto_min;
1555
1556	/* Maximum number of new data packets that can be sent in a burst.  */
1557	int max_burst;
1558
1559	/* This is the max_retrans value for the association.  This value will
1560	 * be initialized initialized from system defaults, but can be
1561	 * modified by the SCTP_ASSOCINFO socket option.
1562	 */
1563	int max_retrans;
1564
1565	/* This is the partially failed retrans value for the transport
1566	 * and will be initialized from the assocs value.  This can be
1567	 * changed using the SCTP_PEER_ADDR_THLDS socket option
1568	 */
1569	int pf_retrans;
1570
1571	/* Maximum number of times the endpoint will retransmit INIT  */
1572	__u16 max_init_attempts;
1573
1574	/* How many times have we resent an INIT? */
1575	__u16 init_retries;
1576
1577	/* The largest timeout or RTO value to use in attempting an INIT */
1578	unsigned long max_init_timeo;
1579
1580	/* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1581	 * the destination address every heartbeat interval. This value
1582	 * will be inherited by all new transports.
1583	 */
1584	unsigned long hbinterval;
1585
1586	/* This is the max_retrans value for new transports in the
1587	 * association.
1588	 */
1589	__u16 pathmaxrxt;
1590
1591	/* Flag that path mtu update is pending */
1592	__u8   pmtu_pending;
1593
1594	/* Association : The smallest PMTU discovered for all of the
1595	 * PMTU	       : peer's transport addresses.
1596	 */
1597	__u32 pathmtu;
1598
1599	/* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1600	__u32 param_flags;
1601
1602	__u32 sackfreq;
1603	/* SACK delay timeout */
1604	unsigned long sackdelay;
 
 
1605
1606	unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES];
1607	struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1608
1609	/* Transport to which SHUTDOWN chunk was last sent.  */
1610	struct sctp_transport *shutdown_last_sent_to;
1611
1612	/* Transport to which INIT chunk was last sent.  */
1613	struct sctp_transport *init_last_sent_to;
1614
1615	/* How many times have we resent a SHUTDOWN */
1616	int shutdown_retries;
1617
 
 
 
1618	/* Next TSN    : The next TSN number to be assigned to a new
1619	 *	       : DATA chunk.  This is sent in the INIT or INIT
1620	 *	       : ACK chunk to the peer and incremented each
1621	 *	       : time a DATA chunk is assigned a TSN
1622	 *	       : (normally just prior to transmit or during
1623	 *	       : fragmentation).
1624	 */
1625	__u32 next_tsn;
1626
1627	/*
1628	 * Last Rcvd   : This is the last TSN received in sequence.  This value
1629	 * TSN	       : is set initially by taking the peer's Initial TSN,
1630	 *	       : received in the INIT or INIT ACK chunk, and
1631	 *	       : subtracting one from it.
1632	 *
1633	 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1634	 */
1635
1636	__u32 ctsn_ack_point;
1637
1638	/* PR-SCTP Advanced.Peer.Ack.Point */
1639	__u32 adv_peer_ack_point;
1640
1641	/* Highest TSN that is acknowledged by incoming SACKs. */
1642	__u32 highest_sacked;
1643
1644	/* TSN marking the fast recovery exit point */
1645	__u32 fast_recovery_exit;
1646
1647	/* Flag to track the current fast recovery state */
1648	__u8 fast_recovery;
1649
1650	/* The number of unacknowledged data chunks.  Reported through
1651	 * the SCTP_STATUS sockopt.
1652	 */
1653	__u16 unack_data;
1654
1655	/* The total number of data chunks that we've had to retransmit
1656	 * as the result of a T3 timer expiration
1657	 */
1658	__u32 rtx_data_chunks;
1659
1660	/* This is the association's receive buffer space.  This value is used
1661	 * to set a_rwnd field in an INIT or a SACK chunk.
1662	 */
1663	__u32 rwnd;
1664
1665	/* This is the last advertised value of rwnd over a SACK chunk. */
1666	__u32 a_rwnd;
1667
1668	/* Number of bytes by which the rwnd has slopped.  The rwnd is allowed
1669	 * to slop over a maximum of the association's frag_point.
1670	 */
1671	__u32 rwnd_over;
1672
1673	/* Keeps treack of rwnd pressure.  This happens when we have
1674	 * a window, but not recevie buffer (i.e small packets).  This one
1675	 * is releases slowly (1 PMTU at a time ).
1676	 */
1677	__u32 rwnd_press;
1678
1679	/* This is the sndbuf size in use for the association.
1680	 * This corresponds to the sndbuf size for the association,
1681	 * as specified in the sk->sndbuf.
1682	 */
1683	int sndbuf_used;
1684
1685	/* This is the amount of memory that this association has allocated
1686	 * in the receive path at any given time.
1687	 */
1688	atomic_t rmem_alloc;
1689
1690	/* This is the wait queue head for send requests waiting on
1691	 * the association sndbuf space.
1692	 */
1693	wait_queue_head_t	wait;
1694
1695	/* The message size at which SCTP fragmentation will occur. */
1696	__u32 frag_point;
1697	__u32 user_frag;
1698
1699	/* Counter used to count INIT errors. */
1700	int init_err_counter;
1701
1702	/* Count the number of INIT cycles (for doubling timeout). */
1703	int init_cycle;
1704
1705	/* Default send parameters. */
1706	__u16 default_stream;
1707	__u16 default_flags;
1708	__u32 default_ppid;
1709	__u32 default_context;
1710	__u32 default_timetolive;
1711
1712	/* Default receive parameters */
1713	__u32 default_rcv_context;
1714
1715	/* This tracks outbound ssn for a given stream.	 */
1716	struct sctp_ssnmap *ssnmap;
1717
1718	/* All outbound chunks go through this structure.  */
1719	struct sctp_outq outqueue;
1720
1721	/* A smart pipe that will handle reordering and fragmentation,
1722	 * as well as handle passing events up to the ULP.
1723	 */
1724	struct sctp_ulpq ulpq;
1725
1726	/* Last TSN that caused an ECNE Chunk to be sent.  */
1727	__u32 last_ecne_tsn;
1728
1729	/* Last TSN that caused a CWR Chunk to be sent.	 */
1730	__u32 last_cwr_tsn;
1731
1732	/* How many duplicated TSNs have we seen?  */
1733	int numduptsns;
1734
 
 
 
 
 
 
1735	/* These are to support
1736	 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1737	 *  and Enforcement of Flow and Message Limits"
1738	 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1739	 * or "ADDIP" for short.
1740	 */
1741
1742
1743
1744	/* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1745	 *
1746	 * R1) One and only one ASCONF Chunk MAY be in transit and
1747	 * unacknowledged at any one time.  If a sender, after sending
1748	 * an ASCONF chunk, decides it needs to transfer another
1749	 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1750	 * returns from the previous ASCONF Chunk before sending a
1751	 * subsequent ASCONF. Note this restriction binds each side,
1752	 * so at any time two ASCONF may be in-transit on any given
1753	 * association (one sent from each endpoint).
1754	 *
1755	 * [This is our one-and-only-one ASCONF in flight.  If we do
1756	 * not have an ASCONF in flight, this is NULL.]
1757	 */
1758	struct sctp_chunk *addip_last_asconf;
1759
1760	/* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
1761	 *
1762	 * This is needed to implement itmes E1 - E4 of the updated
1763	 * spec.  Here is the justification:
1764	 *
1765	 * Since the peer may bundle multiple ASCONF chunks toward us,
1766	 * we now need the ability to cache multiple ACKs.  The section
1767	 * describes in detail how they are cached and cleaned up.
1768	 */
1769	struct list_head asconf_ack_list;
1770
1771	/* These ASCONF chunks are waiting to be sent.
1772	 *
1773	 * These chunaks can't be pushed to outqueue until receiving
1774	 * ASCONF_ACK for the previous ASCONF indicated by
1775	 * addip_last_asconf, so as to guarantee that only one ASCONF
1776	 * is in flight at any time.
1777	 *
1778	 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1779	 *
1780	 * In defining the ASCONF Chunk transfer procedures, it is
1781	 * essential that these transfers MUST NOT cause congestion
1782	 * within the network.	To achieve this, we place these
1783	 * restrictions on the transfer of ASCONF Chunks:
1784	 *
1785	 * R1) One and only one ASCONF Chunk MAY be in transit and
1786	 * unacknowledged at any one time.  If a sender, after sending
1787	 * an ASCONF chunk, decides it needs to transfer another
1788	 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1789	 * returns from the previous ASCONF Chunk before sending a
1790	 * subsequent ASCONF. Note this restriction binds each side,
1791	 * so at any time two ASCONF may be in-transit on any given
1792	 * association (one sent from each endpoint).
1793	 *
1794	 *
1795	 * [I really think this is EXACTLY the sort of intelligence
1796	 *  which already resides in sctp_outq.	 Please move this
1797	 *  queue and its supporting logic down there.	--piggy]
1798	 */
1799	struct list_head addip_chunk_list;
1800
1801	/* ADDIP Section 4.1 ASCONF Chunk Procedures
1802	 *
1803	 * A2) A serial number should be assigned to the Chunk. The
1804	 * serial number SHOULD be a monotonically increasing
1805	 * number. The serial number SHOULD be initialized at
1806	 * the start of the association to the same value as the
1807	 * Initial TSN and every time a new ASCONF chunk is created
1808	 * it is incremented by one after assigning the serial number
1809	 * to the newly created chunk.
1810	 *
1811	 * ADDIP
1812	 * 3.1.1  Address/Stream Configuration Change Chunk (ASCONF)
1813	 *
1814	 * Serial Number : 32 bits (unsigned integer)
1815	 *
1816	 * This value represents a Serial Number for the ASCONF
1817	 * Chunk. The valid range of Serial Number is from 0 to
1818	 * 4294967295 (2^32 - 1).  Serial Numbers wrap back to 0
1819	 * after reaching 4294967295.
1820	 */
1821	__u32 addip_serial;
1822	int src_out_of_asoc_ok;
1823	union sctp_addr *asconf_addr_del_pending;
1824	struct sctp_transport *new_transport;
1825
1826	/* SCTP AUTH: list of the endpoint shared keys.  These
1827	 * keys are provided out of band by the user applicaton
1828	 * and can't change during the lifetime of the association
1829	 */
1830	struct list_head endpoint_shared_keys;
1831
1832	/* SCTP AUTH:
1833	 * The current generated assocaition shared key (secret)
1834	 */
1835	struct sctp_auth_bytes *asoc_shared_key;
1836
1837	/* SCTP AUTH: hmac id of the first peer requested algorithm
1838	 * that we support.
1839	 */
1840	__u16 default_hmac_id;
1841
1842	__u16 active_key_id;
1843
1844	__u8 need_ecne:1,	/* Need to send an ECNE Chunk? */
1845	     temp:1;		/* Is it a temporary association? */
1846
1847	struct sctp_priv_assoc_stats stats;
1848};
1849
1850
1851/* An eyecatcher for determining if we are really looking at an
1852 * association data structure.
1853 */
1854enum {
1855	SCTP_ASSOC_EYECATCHER = 0xa550c123,
1856};
1857
1858/* Recover the outter association structure. */
1859static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
1860{
1861	struct sctp_association *asoc;
1862
1863	asoc = container_of(base, struct sctp_association, base);
1864	return asoc;
1865}
1866
1867/* These are function signatures for manipulating associations.	 */
1868
1869
1870struct sctp_association *
1871sctp_association_new(const struct sctp_endpoint *, const struct sock *,
1872		     sctp_scope_t scope, gfp_t gfp);
1873void sctp_association_free(struct sctp_association *);
1874void sctp_association_put(struct sctp_association *);
1875void sctp_association_hold(struct sctp_association *);
1876
1877struct sctp_transport *sctp_assoc_choose_alter_transport(
1878	struct sctp_association *, struct sctp_transport *);
1879void sctp_assoc_update_retran_path(struct sctp_association *);
1880struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
1881					  const union sctp_addr *);
1882int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1883			    const union sctp_addr *laddr);
1884struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
1885				     const union sctp_addr *address,
1886				     const gfp_t gfp,
1887				     const int peer_state);
1888void sctp_assoc_del_peer(struct sctp_association *asoc,
1889			 const union sctp_addr *addr);
1890void sctp_assoc_rm_peer(struct sctp_association *asoc,
1891			 struct sctp_transport *peer);
1892void sctp_assoc_control_transport(struct sctp_association *,
1893				  struct sctp_transport *,
1894				  sctp_transport_cmd_t, sctp_sn_error_t);
1895struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
1896struct sctp_transport *sctp_assoc_is_match(struct sctp_association *,
1897					   struct net *,
1898					   const union sctp_addr *,
1899					   const union sctp_addr *);
1900void sctp_assoc_migrate(struct sctp_association *, struct sock *);
1901void sctp_assoc_update(struct sctp_association *old,
1902		       struct sctp_association *new);
1903
1904__u32 sctp_association_get_next_tsn(struct sctp_association *);
1905
1906void sctp_assoc_sync_pmtu(struct sock *, struct sctp_association *);
1907void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int);
1908void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int);
1909void sctp_assoc_set_primary(struct sctp_association *,
1910			    struct sctp_transport *);
1911void sctp_assoc_del_nonprimary_peers(struct sctp_association *,
1912				    struct sctp_transport *);
1913int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *,
1914				     sctp_scope_t, gfp_t);
1915int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
1916					 struct sctp_cookie*,
1917					 gfp_t gfp);
1918int sctp_assoc_set_id(struct sctp_association *, gfp_t);
1919void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc);
1920struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
1921					const struct sctp_association *asoc,
1922					__be32 serial);
1923void sctp_asconf_queue_teardown(struct sctp_association *asoc);
1924
1925int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1926			const union sctp_addr *ss2);
1927struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
1928
1929/* A convenience structure to parse out SCTP specific CMSGs. */
1930typedef struct sctp_cmsgs {
1931	struct sctp_initmsg *init;
1932	struct sctp_sndrcvinfo *srinfo;
1933	struct sctp_sndinfo *sinfo;
1934} sctp_cmsgs_t;
1935
1936/* Structure for tracking memory objects */
1937typedef struct {
1938	char *label;
1939	atomic_t *counter;
1940} sctp_dbg_objcnt_entry_t;
1941
1942#endif /* __sctp_structs_h__ */