xref: /openbmc/linux/include/net/sctp/structs.h (revision 31b90347)
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 <linux-sctp@vger.kernel.org>
29  *
30  * Written or modified by:
31  *    Randall Stewart	    <randall@sctp.chicago.il.us>
32  *    Ken Morneau	    <kmorneau@cisco.com>
33  *    Qiaobing Xie	    <qxie1@email.mot.com>
34  *    La Monte H.P. Yarroll <piggy@acm.org>
35  *    Karl Knutson	    <karl@athena.chicago.il.us>
36  *    Jon Grimm		    <jgrimm@us.ibm.com>
37  *    Xingang Guo	    <xingang.guo@intel.com>
38  *    Hui Huang		    <hui.huang@nokia.com>
39  *    Sridhar Samudrala	    <sri@us.ibm.com>
40  *    Daisy Chang	    <daisyc@us.ibm.com>
41  *    Dajiang Zhang	    <dajiang.zhang@nokia.com>
42  *    Ardelle Fan	    <ardelle.fan@intel.com>
43  *    Ryan Layer	    <rmlayer@us.ibm.com>
44  *    Anup Pemmaiah	    <pemmaiah@cc.usu.edu>
45  *    Kevin Gao             <kevin.gao@intel.com>
46  */
47 
48 #ifndef __sctp_structs_h__
49 #define __sctp_structs_h__
50 
51 #include <linux/ktime.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  */
66 union sctp_addr {
67 	struct sockaddr_in v4;
68 	struct sockaddr_in6 v6;
69 	struct sockaddr sa;
70 };
71 
72 /* Forward declarations for data structures. */
73 struct sctp_globals;
74 struct sctp_endpoint;
75 struct sctp_association;
76 struct sctp_transport;
77 struct sctp_packet;
78 struct sctp_chunk;
79 struct sctp_inq;
80 struct sctp_outq;
81 struct sctp_bind_addr;
82 struct sctp_ulpq;
83 struct sctp_ep_common;
84 struct sctp_ssnmap;
85 struct crypto_hash;
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 
94 struct 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 
102 struct sctp_bind_hashbucket {
103 	spinlock_t	lock;
104 	struct hlist_head	chain;
105 };
106 
107 /* Used for hashing all associations.  */
108 struct sctp_hashbucket {
109 	rwlock_t	lock;
110 	struct hlist_head	chain;
111 } __attribute__((__aligned__(8)));
112 
113 
114 /* The SCTP globals structure. */
115 extern struct sctp_globals {
116 	/* This is a list of groups of functions for each address
117 	 * family that we support.
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 hash of all associations. */
124 	struct sctp_hashbucket *assoc_hashtable;
125 	/* This is the sctp port control hash.	*/
126 	struct sctp_bind_hashbucket *port_hashtable;
127 
128 	/* Sizes of above hashtables. */
129 	int ep_hashsize;
130 	int assoc_hashsize;
131 	int port_hashsize;
132 
133 	/* Default initialization values to be applied to new associations. */
134 	__u16 max_instreams;
135 	__u16 max_outstreams;
136 
137 	/* Flag to indicate whether computing and verifying checksum
138 	 * is disabled. */
139         bool checksum_disable;
140 } sctp_globals;
141 
142 #define sctp_max_instreams		(sctp_globals.max_instreams)
143 #define sctp_max_outstreams		(sctp_globals.max_outstreams)
144 #define sctp_address_families		(sctp_globals.address_families)
145 #define sctp_ep_hashsize		(sctp_globals.ep_hashsize)
146 #define sctp_ep_hashtable		(sctp_globals.ep_hashtable)
147 #define sctp_assoc_hashsize		(sctp_globals.assoc_hashsize)
148 #define sctp_assoc_hashtable		(sctp_globals.assoc_hashtable)
149 #define sctp_port_hashsize		(sctp_globals.port_hashsize)
150 #define sctp_port_hashtable		(sctp_globals.port_hashtable)
151 #define sctp_checksum_disable		(sctp_globals.checksum_disable)
152 
153 /* SCTP Socket type: UDP or TCP style. */
154 typedef enum {
155 	SCTP_SOCKET_UDP = 0,
156 	SCTP_SOCKET_UDP_HIGH_BANDWIDTH,
157 	SCTP_SOCKET_TCP
158 } sctp_socket_type_t;
159 
160 /* Per socket SCTP information. */
161 struct sctp_sock {
162 	/* inet_sock has to be the first member of sctp_sock */
163 	struct inet_sock inet;
164 	/* What kind of a socket is this? */
165 	sctp_socket_type_t type;
166 
167 	/* PF_ family specific functions.  */
168 	struct sctp_pf *pf;
169 
170 	/* Access to HMAC transform. */
171 	struct crypto_hash *hmac;
172 	char *sctp_hmac_alg;
173 
174 	/* What is our base endpointer? */
175 	struct sctp_endpoint *ep;
176 
177 	struct sctp_bind_bucket *bind_hash;
178 	/* Various Socket Options.  */
179 	__u16 default_stream;
180 	__u32 default_ppid;
181 	__u16 default_flags;
182 	__u32 default_context;
183 	__u32 default_timetolive;
184 	__u32 default_rcv_context;
185 	int max_burst;
186 
187 	/* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
188 	 * the destination address every heartbeat interval. This value
189 	 * will be inherited by all new associations.
190 	 */
191 	__u32 hbinterval;
192 
193 	/* This is the max_retrans value for new associations. */
194 	__u16 pathmaxrxt;
195 
196 	/* The initial Path MTU to use for new associations. */
197 	__u32 pathmtu;
198 
199 	/* The default SACK delay timeout for new associations. */
200 	__u32 sackdelay;
201 	__u32 sackfreq;
202 
203 	/* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
204 	__u32 param_flags;
205 
206 	struct sctp_initmsg initmsg;
207 	struct sctp_rtoinfo rtoinfo;
208 	struct sctp_paddrparams paddrparam;
209 	struct sctp_event_subscribe subscribe;
210 	struct sctp_assocparams assocparams;
211 	int user_frag;
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 
220 	atomic_t pd_mode;
221 	/* Receive to here while partial delivery is in effect. */
222 	struct sk_buff_head pd_lobby;
223 	struct list_head auto_asconf_list;
224 	int do_auto_asconf;
225 };
226 
227 static inline struct sctp_sock *sctp_sk(const struct sock *sk)
228 {
229        return (struct sctp_sock *)sk;
230 }
231 
232 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
233 {
234        return (struct sock *)sp;
235 }
236 
237 #if IS_ENABLED(CONFIG_IPV6)
238 struct sctp6_sock {
239        struct sctp_sock  sctp;
240        struct ipv6_pinfo inet6;
241 };
242 #endif /* CONFIG_IPV6 */
243 
244 
245 /* This is our APPLICATION-SPECIFIC state cookie.
246  * THIS IS NOT DICTATED BY THE SPECIFICATION.
247  */
248 /* These are the parts of an association which we send in the cookie.
249  * Most of these are straight out of:
250  * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
251  *
252  */
253 
254 struct sctp_cookie {
255 
256 	/* My	       : Tag expected in every inbound packet and sent
257 	 * Verification: in the INIT or INIT ACK chunk.
258 	 * Tag	       :
259 	 */
260 	__u32 my_vtag;
261 
262 	/* Peer's      : Tag expected in every outbound packet except
263 	 * Verification: in the INIT chunk.
264 	 * Tag	       :
265 	 */
266 	__u32 peer_vtag;
267 
268 	/* The rest of these are not from the spec, but really need to
269 	 * be in the cookie.
270 	 */
271 
272 	/* My Tie Tag  : Assist in discovering a restarting association. */
273 	__u32 my_ttag;
274 
275 	/* Peer's Tie Tag: Assist in discovering a restarting association. */
276 	__u32 peer_ttag;
277 
278 	/* When does this cookie expire? */
279 	ktime_t expiration;
280 
281 	/* Number of inbound/outbound streams which are set
282 	 * and negotiated during the INIT process.
283 	 */
284 	__u16 sinit_num_ostreams;
285 	__u16 sinit_max_instreams;
286 
287 	/* This is the first sequence number I used.  */
288 	__u32 initial_tsn;
289 
290 	/* This holds the originating address of the INIT packet.  */
291 	union sctp_addr peer_addr;
292 
293 	/* IG Section 2.35.3
294 	 * Include the source port of the INIT-ACK
295 	 */
296 	__u16		my_port;
297 
298 	__u8 prsctp_capable;
299 
300 	/* Padding for future use */
301 	__u8 padding;
302 
303 	__u32 adaptation_ind;
304 
305 	__u8 auth_random[sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH];
306 	__u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2];
307 	__u8 auth_chunks[sizeof(sctp_paramhdr_t) + SCTP_AUTH_MAX_CHUNKS];
308 
309 	/* This is a shim for my peer's INIT packet, followed by
310 	 * a copy of the raw address list of the association.
311 	 * The length of the raw address list is saved in the
312 	 * raw_addr_list_len field, which will be used at the time when
313 	 * the association TCB is re-constructed from the cookie.
314 	 */
315 	__u32 raw_addr_list_len;
316 	struct sctp_init_chunk peer_init[0];
317 };
318 
319 
320 /* The format of our cookie that we send to our peer. */
321 struct sctp_signed_cookie {
322 	__u8 signature[SCTP_SECRET_SIZE];
323 	__u32 __pad;		/* force sctp_cookie alignment to 64 bits */
324 	struct sctp_cookie c;
325 } __packed;
326 
327 /* This is another convenience type to allocate memory for address
328  * params for the maximum size and pass such structures around
329  * internally.
330  */
331 union sctp_addr_param {
332 	struct sctp_paramhdr p;
333 	struct sctp_ipv4addr_param v4;
334 	struct sctp_ipv6addr_param v6;
335 };
336 
337 /* A convenience type to allow walking through the various
338  * parameters and avoid casting all over the place.
339  */
340 union sctp_params {
341 	void *v;
342 	struct sctp_paramhdr *p;
343 	struct sctp_cookie_preserve_param *life;
344 	struct sctp_hostname_param *dns;
345 	struct sctp_cookie_param *cookie;
346 	struct sctp_supported_addrs_param *sat;
347 	struct sctp_ipv4addr_param *v4;
348 	struct sctp_ipv6addr_param *v6;
349 	union sctp_addr_param *addr;
350 	struct sctp_adaptation_ind_param *aind;
351 	struct sctp_supported_ext_param *ext;
352 	struct sctp_random_param *random;
353 	struct sctp_chunks_param *chunks;
354 	struct sctp_hmac_algo_param *hmac_algo;
355 	struct sctp_addip_param *addip;
356 };
357 
358 /* RFC 2960.  Section 3.3.5 Heartbeat.
359  *    Heartbeat Information: variable length
360  *    The Sender-specific Heartbeat Info field should normally include
361  *    information about the sender's current time when this HEARTBEAT
362  *    chunk is sent and the destination transport address to which this
363  *    HEARTBEAT is sent (see Section 8.3).
364  */
365 typedef struct sctp_sender_hb_info {
366 	struct sctp_paramhdr param_hdr;
367 	union sctp_addr daddr;
368 	unsigned long sent_at;
369 	__u64 hb_nonce;
370 } __packed sctp_sender_hb_info_t;
371 
372 /*
373  *  RFC 2960 1.3.2 Sequenced Delivery within Streams
374  *
375  *  The term "stream" is used in SCTP to refer to a sequence of user
376  *  messages that are to be delivered to the upper-layer protocol in
377  *  order with respect to other messages within the same stream.  This is
378  *  in contrast to its usage in TCP, where it refers to a sequence of
379  *  bytes (in this document a byte is assumed to be eight bits).
380  *  ...
381  *
382  *  This is the structure we use to track both our outbound and inbound
383  *  SSN, or Stream Sequence Numbers.
384  */
385 
386 struct sctp_stream {
387 	__u16 *ssn;
388 	unsigned int len;
389 };
390 
391 struct sctp_ssnmap {
392 	struct sctp_stream in;
393 	struct sctp_stream out;
394 };
395 
396 struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out,
397 				    gfp_t gfp);
398 void sctp_ssnmap_free(struct sctp_ssnmap *map);
399 void sctp_ssnmap_clear(struct sctp_ssnmap *map);
400 
401 /* What is the current SSN number for this stream? */
402 static inline __u16 sctp_ssn_peek(struct sctp_stream *stream, __u16 id)
403 {
404 	return stream->ssn[id];
405 }
406 
407 /* Return the next SSN number for this stream.	*/
408 static inline __u16 sctp_ssn_next(struct sctp_stream *stream, __u16 id)
409 {
410 	return stream->ssn[id]++;
411 }
412 
413 /* Skip over this ssn and all below. */
414 static inline void sctp_ssn_skip(struct sctp_stream *stream, __u16 id,
415 				 __u16 ssn)
416 {
417 	stream->ssn[id] = ssn+1;
418 }
419 
420 /*
421  * Pointers to address related SCTP functions.
422  * (i.e. things that depend on the address family.)
423  */
424 struct sctp_af {
425 	int		(*sctp_xmit)	(struct sk_buff *skb,
426 					 struct sctp_transport *);
427 	int		(*setsockopt)	(struct sock *sk,
428 					 int level,
429 					 int optname,
430 					 char __user *optval,
431 					 unsigned int optlen);
432 	int		(*getsockopt)	(struct sock *sk,
433 					 int level,
434 					 int optname,
435 					 char __user *optval,
436 					 int __user *optlen);
437 	int		(*compat_setsockopt)	(struct sock *sk,
438 					 int level,
439 					 int optname,
440 					 char __user *optval,
441 					 unsigned int optlen);
442 	int		(*compat_getsockopt)	(struct sock *sk,
443 					 int level,
444 					 int optname,
445 					 char __user *optval,
446 					 int __user *optlen);
447 	void		(*get_dst)	(struct sctp_transport *t,
448 					 union sctp_addr *saddr,
449 					 struct flowi *fl,
450 					 struct sock *sk);
451 	void		(*get_saddr)	(struct sctp_sock *sk,
452 					 struct sctp_transport *t,
453 					 struct flowi *fl);
454 	void		(*copy_addrlist) (struct list_head *,
455 					  struct net_device *);
456 	int		(*cmp_addr)	(const union sctp_addr *addr1,
457 					 const union sctp_addr *addr2);
458 	void		(*addr_copy)	(union sctp_addr *dst,
459 					 union sctp_addr *src);
460 	void		(*from_skb)	(union sctp_addr *,
461 					 struct sk_buff *skb,
462 					 int saddr);
463 	void		(*from_sk)	(union sctp_addr *,
464 					 struct sock *sk);
465 	void		(*to_sk_saddr)	(union sctp_addr *,
466 					 struct sock *sk);
467 	void		(*to_sk_daddr)	(union sctp_addr *,
468 					 struct sock *sk);
469 	void		(*from_addr_param) (union sctp_addr *,
470 					    union sctp_addr_param *,
471 					    __be16 port, int iif);
472 	int		(*to_addr_param) (const union sctp_addr *,
473 					  union sctp_addr_param *);
474 	int		(*addr_valid)	(union sctp_addr *,
475 					 struct sctp_sock *,
476 					 const struct sk_buff *);
477 	sctp_scope_t	(*scope) (union sctp_addr *);
478 	void		(*inaddr_any)	(union sctp_addr *, __be16);
479 	int		(*is_any)	(const union sctp_addr *);
480 	int		(*available)	(union sctp_addr *,
481 					 struct sctp_sock *);
482 	int		(*skb_iif)	(const struct sk_buff *sk);
483 	int		(*is_ce)	(const struct sk_buff *sk);
484 	void		(*seq_dump_addr)(struct seq_file *seq,
485 					 union sctp_addr *addr);
486 	void		(*ecn_capable)(struct sock *sk);
487 	__u16		net_header_len;
488 	int		sockaddr_len;
489 	sa_family_t	sa_family;
490 	struct list_head list;
491 };
492 
493 struct sctp_af *sctp_get_af_specific(sa_family_t);
494 int sctp_register_af(struct sctp_af *);
495 
496 /* Protocol family functions. */
497 struct sctp_pf {
498 	void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
499 	void (*skb_msgname)  (struct sk_buff *, char *, int *);
500 	int  (*af_supported) (sa_family_t, struct sctp_sock *);
501 	int  (*cmp_addr) (const union sctp_addr *,
502 			  const union sctp_addr *,
503 			  struct sctp_sock *);
504 	int  (*bind_verify) (struct sctp_sock *, union sctp_addr *);
505 	int  (*send_verify) (struct sctp_sock *, union sctp_addr *);
506 	int  (*supported_addrs)(const struct sctp_sock *, __be16 *);
507 	struct sock *(*create_accept_sk) (struct sock *sk,
508 					  struct sctp_association *asoc);
509 	void (*addr_v4map) (struct sctp_sock *, union sctp_addr *);
510 	struct sctp_af *af;
511 };
512 
513 
514 /* Structure to track chunk fragments that have been acked, but peer
515  * fragments of the same message have not.
516  */
517 struct sctp_datamsg {
518 	/* Chunks waiting to be submitted to lower layer. */
519 	struct list_head chunks;
520 	/* Reference counting. */
521 	atomic_t refcnt;
522 	/* When is this message no longer interesting to the peer? */
523 	unsigned long expires_at;
524 	/* Did the messenge fail to send? */
525 	int send_error;
526 	u8 send_failed:1,
527 	   can_abandon:1,   /* can chunks from this message can be abandoned. */
528 	   can_delay;	    /* should this message be Nagle delayed */
529 };
530 
531 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
532 					    struct sctp_sndrcvinfo *,
533 					    struct msghdr *, int len);
534 void sctp_datamsg_free(struct sctp_datamsg *);
535 void sctp_datamsg_put(struct sctp_datamsg *);
536 void sctp_chunk_fail(struct sctp_chunk *, int error);
537 int sctp_chunk_abandoned(struct sctp_chunk *);
538 
539 /* RFC2960 1.4 Key Terms
540  *
541  * o Chunk: A unit of information within an SCTP packet, consisting of
542  * a chunk header and chunk-specific content.
543  *
544  * As a matter of convenience, we remember the SCTP common header for
545  * each chunk as well as a few other header pointers...
546  */
547 struct sctp_chunk {
548 	struct list_head list;
549 
550 	atomic_t refcnt;
551 
552 	/* This is our link to the per-transport transmitted list.  */
553 	struct list_head transmitted_list;
554 
555 	/* This field is used by chunks that hold fragmented data.
556 	 * For the first fragment this is the list that holds the rest of
557 	 * fragments. For the remaining fragments, this is the link to the
558 	 * frag_list maintained in the first fragment.
559 	 */
560 	struct list_head frag_list;
561 
562 	/* This points to the sk_buff containing the actual data.  */
563 	struct sk_buff *skb;
564 
565 	/* These are the SCTP headers by reverse order in a packet.
566 	 * Note that some of these may happen more than once.  In that
567 	 * case, we point at the "current" one, whatever that means
568 	 * for that level of header.
569 	 */
570 
571 	/* We point this at the FIRST TLV parameter to chunk_hdr.  */
572 	union sctp_params param_hdr;
573 	union {
574 		__u8 *v;
575 		struct sctp_datahdr *data_hdr;
576 		struct sctp_inithdr *init_hdr;
577 		struct sctp_sackhdr *sack_hdr;
578 		struct sctp_heartbeathdr *hb_hdr;
579 		struct sctp_sender_hb_info *hbs_hdr;
580 		struct sctp_shutdownhdr *shutdown_hdr;
581 		struct sctp_signed_cookie *cookie_hdr;
582 		struct sctp_ecnehdr *ecne_hdr;
583 		struct sctp_cwrhdr *ecn_cwr_hdr;
584 		struct sctp_errhdr *err_hdr;
585 		struct sctp_addiphdr *addip_hdr;
586 		struct sctp_fwdtsn_hdr *fwdtsn_hdr;
587 		struct sctp_authhdr *auth_hdr;
588 	} subh;
589 
590 	__u8 *chunk_end;
591 
592 	struct sctp_chunkhdr *chunk_hdr;
593 	struct sctphdr *sctp_hdr;
594 
595 	/* This needs to be recoverable for SCTP_SEND_FAILED events. */
596 	struct sctp_sndrcvinfo sinfo;
597 
598 	/* Which association does this belong to?  */
599 	struct sctp_association *asoc;
600 
601 	/* What endpoint received this chunk? */
602 	struct sctp_ep_common *rcvr;
603 
604 	/* We fill this in if we are calculating RTT. */
605 	unsigned long sent_at;
606 
607 	/* What is the origin IP address for this chunk?  */
608 	union sctp_addr source;
609 	/* Destination address for this chunk. */
610 	union sctp_addr dest;
611 
612 	/* For outbound message, track all fragments for SEND_FAILED. */
613 	struct sctp_datamsg *msg;
614 
615 	/* For an inbound chunk, this tells us where it came from.
616 	 * For an outbound chunk, it tells us where we'd like it to
617 	 * go.	It is NULL if we have no preference.
618 	 */
619 	struct sctp_transport *transport;
620 
621 	/* SCTP-AUTH:  For the special case inbound processing of COOKIE-ECHO
622 	 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
623 	 * spec violates the principle premis that all chunks are processed
624 	 * in order.
625 	 */
626 	struct sk_buff *auth_chunk;
627 
628 #define SCTP_CAN_FRTX 0x0
629 #define SCTP_NEED_FRTX 0x1
630 #define SCTP_DONT_FRTX 0x2
631 	__u16	rtt_in_progress:1,	/* This chunk used for RTT calc? */
632 		resent:1,		/* Has this chunk ever been resent. */
633 		has_tsn:1,		/* Does this chunk have a TSN yet? */
634 		has_ssn:1,		/* Does this chunk have a SSN yet? */
635 		singleton:1,		/* Only chunk in the packet? */
636 		end_of_packet:1,	/* Last chunk in the packet? */
637 		ecn_ce_done:1,		/* Have we processed the ECN CE bit? */
638 		pdiscard:1,		/* Discard the whole packet now? */
639 		tsn_gap_acked:1,	/* Is this chunk acked by a GAP ACK? */
640 		data_accepted:1,	/* At least 1 chunk accepted */
641 		auth:1,			/* IN: was auth'ed | OUT: needs auth */
642 		has_asconf:1,		/* IN: have seen an asconf before */
643 		tsn_missing_report:2,	/* Data chunk missing counter. */
644 		fast_retransmit:2;	/* Is this chunk fast retransmitted? */
645 };
646 
647 void sctp_chunk_hold(struct sctp_chunk *);
648 void sctp_chunk_put(struct sctp_chunk *);
649 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
650 			  struct iovec *data);
651 void sctp_chunk_free(struct sctp_chunk *);
652 void  *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
653 void  *sctp_addto_chunk_fixed(struct sctp_chunk *, int len, const void *data);
654 struct sctp_chunk *sctp_chunkify(struct sk_buff *,
655 				 const struct sctp_association *,
656 				 struct sock *);
657 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
658 		     union sctp_addr *);
659 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
660 
661 enum {
662 	SCTP_ADDR_NEW,		/* new address added to assoc/ep */
663 	SCTP_ADDR_SRC,		/* address can be used as source */
664 	SCTP_ADDR_DEL,		/* address about to be deleted */
665 };
666 
667 /* This is a structure for holding either an IPv6 or an IPv4 address.  */
668 struct sctp_sockaddr_entry {
669 	struct list_head list;
670 	struct rcu_head	rcu;
671 	union sctp_addr a;
672 	__u8 state;
673 	__u8 valid;
674 };
675 
676 #define SCTP_ADDRESS_TICK_DELAY	500
677 
678 typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *);
679 
680 /* This structure holds lists of chunks as we are assembling for
681  * transmission.
682  */
683 struct sctp_packet {
684 	/* These are the SCTP header values (host order) for the packet. */
685 	__u16 source_port;
686 	__u16 destination_port;
687 	__u32 vtag;
688 
689 	/* This contains the payload chunks.  */
690 	struct list_head chunk_list;
691 
692 	/* This is the overhead of the sctp and ip headers. */
693 	size_t overhead;
694 	/* This is the total size of all chunks INCLUDING padding.  */
695 	size_t size;
696 
697 	/* The packet is destined for this transport address.
698 	 * The function we finally use to pass down to the next lower
699 	 * layer lives in the transport structure.
700 	 */
701 	struct sctp_transport *transport;
702 
703 	/* pointer to the auth chunk for this packet */
704 	struct sctp_chunk *auth;
705 
706 	u8  has_cookie_echo:1,	/* This packet contains a COOKIE-ECHO chunk. */
707 	    has_sack:1,		/* This packet contains a SACK chunk. */
708 	    has_auth:1,		/* This packet contains an AUTH chunk */
709 	    has_data:1,		/* This packet contains at least 1 DATA chunk */
710 	    ipfragok:1;		/* So let ip fragment this packet */
711 };
712 
713 struct sctp_packet *sctp_packet_init(struct sctp_packet *,
714 				     struct sctp_transport *,
715 				     __u16 sport, __u16 dport);
716 struct sctp_packet *sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
717 sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *,
718                                        struct sctp_chunk *, int);
719 sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *,
720                                      struct sctp_chunk *);
721 int sctp_packet_transmit(struct sctp_packet *);
722 void sctp_packet_free(struct sctp_packet *);
723 
724 static inline int sctp_packet_empty(struct sctp_packet *packet)
725 {
726 	return packet->size == packet->overhead;
727 }
728 
729 /* This represents a remote transport address.
730  * For local transport addresses, we just use union sctp_addr.
731  *
732  * RFC2960 Section 1.4 Key Terms
733  *
734  *   o	Transport address:  A Transport Address is traditionally defined
735  *	by Network Layer address, Transport Layer protocol and Transport
736  *	Layer port number.  In the case of SCTP running over IP, a
737  *	transport address is defined by the combination of an IP address
738  *	and an SCTP port number (where SCTP is the Transport protocol).
739  *
740  * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
741  *
742  *   o	The sender keeps a separate congestion control parameter set for
743  *	each of the destination addresses it can send to (not each
744  *	source-destination pair but for each destination).  The parameters
745  *	should decay if the address is not used for a long enough time
746  *	period.
747  *
748  */
749 struct sctp_transport {
750 	/* A list of transports. */
751 	struct list_head transports;
752 
753 	/* Reference counting. */
754 	atomic_t refcnt;
755 	__u32	 dead:1,
756 		/* RTO-Pending : A flag used to track if one of the DATA
757 		 *		chunks sent to this address is currently being
758 		 *		used to compute a RTT. If this flag is 0,
759 		 *		the next DATA chunk sent to this destination
760 		 *		should be used to compute a RTT and this flag
761 		 *		should be set. Every time the RTT
762 		 *		calculation completes (i.e. the DATA chunk
763 		 *		is SACK'd) clear this flag.
764 		 */
765 		 rto_pending:1,
766 
767 		/*
768 		 * hb_sent : a flag that signals that we have a pending
769 		 * heartbeat.
770 		 */
771 		hb_sent:1,
772 
773 		/* Is the Path MTU update pending on this tranport */
774 		pmtu_pending:1;
775 
776 	/* Has this transport moved the ctsn since we last sacked */
777 	__u32 sack_generation;
778 	u32 dst_cookie;
779 
780 	struct flowi fl;
781 
782 	/* This is the peer's IP address and port. */
783 	union sctp_addr ipaddr;
784 
785 	/* These are the functions we call to handle LLP stuff.	 */
786 	struct sctp_af *af_specific;
787 
788 	/* Which association do we belong to?  */
789 	struct sctp_association *asoc;
790 
791 	/* RFC2960
792 	 *
793 	 * 12.3 Per Transport Address Data
794 	 *
795 	 * For each destination transport address in the peer's
796 	 * address list derived from the INIT or INIT ACK chunk, a
797 	 * number of data elements needs to be maintained including:
798 	 */
799 	/* RTO	       : The current retransmission timeout value.  */
800 	unsigned long rto;
801 
802 	__u32 rtt;		/* This is the most recent RTT.	 */
803 
804 	/* RTTVAR      : The current RTT variation.  */
805 	__u32 rttvar;
806 
807 	/* SRTT	       : The current smoothed round trip time.	*/
808 	__u32 srtt;
809 
810 	/*
811 	 * These are the congestion stats.
812 	 */
813 	/* cwnd	       : The current congestion window.	 */
814 	__u32 cwnd;		  /* This is the actual cwnd.  */
815 
816 	/* ssthresh    : The current slow start threshold value.  */
817 	__u32 ssthresh;
818 
819 	/* partial     : The tracking method for increase of cwnd when in
820 	 * bytes acked : congestion avoidance mode (see Section 6.2.2)
821 	 */
822 	__u32 partial_bytes_acked;
823 
824 	/* Data that has been sent, but not acknowledged. */
825 	__u32 flight_size;
826 
827 	__u32 burst_limited;	/* Holds old cwnd when max.burst is applied */
828 
829 	/* Destination */
830 	struct dst_entry *dst;
831 	/* Source address. */
832 	union sctp_addr saddr;
833 
834 	/* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
835 	 * the destination address every heartbeat interval.
836 	 */
837 	unsigned long hbinterval;
838 
839 	/* SACK delay timeout */
840 	unsigned long sackdelay;
841 	__u32 sackfreq;
842 
843 	/* When was the last time (in jiffies) that we heard from this
844 	 * transport?  We use this to pick new active and retran paths.
845 	 */
846 	unsigned long last_time_heard;
847 
848 	/* Last time(in jiffies) when cwnd is reduced due to the congestion
849 	 * indication based on ECNE chunk.
850 	 */
851 	unsigned long last_time_ecne_reduced;
852 
853 	/* This is the max_retrans value for the transport and will
854 	 * be initialized from the assocs value.  This can be changed
855 	 * using the SCTP_SET_PEER_ADDR_PARAMS socket option.
856 	 */
857 	__u16 pathmaxrxt;
858 
859 	/* This is the partially failed retrans value for the transport
860 	 * and will be initialized from the assocs value.  This can be changed
861 	 * using the SCTP_PEER_ADDR_THLDS socket option
862 	 */
863 	int pf_retrans;
864 	/* PMTU	      : The current known path MTU.  */
865 	__u32 pathmtu;
866 
867 	/* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
868 	__u32 param_flags;
869 
870 	/* The number of times INIT has been sent on this transport. */
871 	int init_sent_count;
872 
873 	/* state       : The current state of this destination,
874 	 *             : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
875 	 */
876 	int state;
877 
878 	/* These are the error stats for this destination.  */
879 
880 	/* Error count : The current error count for this destination.	*/
881 	unsigned short error_count;
882 
883 	/* Per	       : A timer used by each destination.
884 	 * Destination :
885 	 * Timer       :
886 	 *
887 	 * [Everywhere else in the text this is called T3-rtx. -ed]
888 	 */
889 	struct timer_list T3_rtx_timer;
890 
891 	/* Heartbeat timer is per destination. */
892 	struct timer_list hb_timer;
893 
894 	/* Timer to handle ICMP proto unreachable envets */
895 	struct timer_list proto_unreach_timer;
896 
897 	/* Since we're using per-destination retransmission timers
898 	 * (see above), we're also using per-destination "transmitted"
899 	 * queues.  This probably ought to be a private struct
900 	 * accessible only within the outqueue, but it's not, yet.
901 	 */
902 	struct list_head transmitted;
903 
904 	/* We build bundle-able packets for this transport here.  */
905 	struct sctp_packet packet;
906 
907 	/* This is the list of transports that have chunks to send.  */
908 	struct list_head send_ready;
909 
910 	/* State information saved for SFR_CACC algorithm. The key
911 	 * idea in SFR_CACC is to maintain state at the sender on a
912 	 * per-destination basis when a changeover happens.
913 	 *	char changeover_active;
914 	 *	char cycling_changeover;
915 	 *	__u32 next_tsn_at_change;
916 	 *	char cacc_saw_newack;
917 	 */
918 	struct {
919 		/* An unsigned integer, which stores the next TSN to be
920 		 * used by the sender, at the moment of changeover.
921 		 */
922 		__u32 next_tsn_at_change;
923 
924 		/* A flag which indicates the occurrence of a changeover */
925 		char changeover_active;
926 
927 		/* A flag which indicates whether the change of primary is
928 		 * the first switch to this destination address during an
929 		 * active switch.
930 		 */
931 		char cycling_changeover;
932 
933 		/* A temporary flag, which is used during the processing of
934 		 * a SACK to estimate the causative TSN(s)'s group.
935 		 */
936 		char cacc_saw_newack;
937 	} cacc;
938 
939 	/* 64-bit random number sent with heartbeat. */
940 	__u64 hb_nonce;
941 
942 	struct rcu_head rcu;
943 };
944 
945 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *,
946 					  gfp_t);
947 void sctp_transport_set_owner(struct sctp_transport *,
948 			      struct sctp_association *);
949 void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
950 			  struct sctp_sock *);
951 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk);
952 void sctp_transport_free(struct sctp_transport *);
953 void sctp_transport_reset_timers(struct sctp_transport *);
954 void sctp_transport_hold(struct sctp_transport *);
955 void sctp_transport_put(struct sctp_transport *);
956 void sctp_transport_update_rto(struct sctp_transport *, __u32);
957 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
958 void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t);
959 void sctp_transport_burst_limited(struct sctp_transport *);
960 void sctp_transport_burst_reset(struct sctp_transport *);
961 unsigned long sctp_transport_timeout(struct sctp_transport *);
962 void sctp_transport_reset(struct sctp_transport *);
963 void sctp_transport_update_pmtu(struct sock *, struct sctp_transport *, u32);
964 void sctp_transport_immediate_rtx(struct sctp_transport *);
965 
966 
967 /* This is the structure we use to queue packets as they come into
968  * SCTP.  We write packets to it and read chunks from it.
969  */
970 struct sctp_inq {
971 	/* This is actually a queue of sctp_chunk each
972 	 * containing a partially decoded packet.
973 	 */
974 	struct list_head in_chunk_list;
975 	/* This is the packet which is currently off the in queue and is
976 	 * being worked on through the inbound chunk processing.
977 	 */
978 	struct sctp_chunk *in_progress;
979 
980 	/* This is the delayed task to finish delivering inbound
981 	 * messages.
982 	 */
983 	struct work_struct immediate;
984 };
985 
986 void sctp_inq_init(struct sctp_inq *);
987 void sctp_inq_free(struct sctp_inq *);
988 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
989 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
990 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *);
991 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t);
992 
993 /* This is the structure we use to hold outbound chunks.  You push
994  * chunks in and they automatically pop out the other end as bundled
995  * packets (it calls (*output_handler)()).
996  *
997  * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
998  * and 8.2 of the v13 draft.
999  *
1000  * It handles retransmissions.	The connection to the timeout portion
1001  * of the state machine is through sctp_..._timeout() and timeout_handler.
1002  *
1003  * If you feed it SACKs, it will eat them.
1004  *
1005  * If you give it big chunks, it will fragment them.
1006  *
1007  * It assigns TSN's to data chunks.  This happens at the last possible
1008  * instant before transmission.
1009  *
1010  * When free()'d, it empties itself out via output_handler().
1011  */
1012 struct sctp_outq {
1013 	struct sctp_association *asoc;
1014 
1015 	/* Data pending that has never been transmitted.  */
1016 	struct list_head out_chunk_list;
1017 
1018 	unsigned int out_qlen;	/* Total length of queued data chunks. */
1019 
1020 	/* Error of send failed, may used in SCTP_SEND_FAILED event. */
1021 	unsigned int error;
1022 
1023 	/* These are control chunks we want to send.  */
1024 	struct list_head control_chunk_list;
1025 
1026 	/* These are chunks that have been sacked but are above the
1027 	 * CTSN, or cumulative tsn ack point.
1028 	 */
1029 	struct list_head sacked;
1030 
1031 	/* Put chunks on this list to schedule them for
1032 	 * retransmission.
1033 	 */
1034 	struct list_head retransmit;
1035 
1036 	/* Put chunks on this list to save them for FWD TSN processing as
1037 	 * they were abandoned.
1038 	 */
1039 	struct list_head abandoned;
1040 
1041 	/* How many unackd bytes do we have in-flight?	*/
1042 	__u32 outstanding_bytes;
1043 
1044 	/* Are we doing fast-rtx on this queue */
1045 	char fast_rtx;
1046 
1047 	/* Corked? */
1048 	char cork;
1049 };
1050 
1051 void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1052 void sctp_outq_teardown(struct sctp_outq *);
1053 void sctp_outq_free(struct sctp_outq*);
1054 int sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk);
1055 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *);
1056 int sctp_outq_is_empty(const struct sctp_outq *);
1057 void sctp_outq_restart(struct sctp_outq *);
1058 
1059 void sctp_retransmit(struct sctp_outq *, struct sctp_transport *,
1060 		     sctp_retransmit_reason_t);
1061 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1062 int sctp_outq_uncork(struct sctp_outq *);
1063 /* Uncork and flush an outqueue.  */
1064 static inline void sctp_outq_cork(struct sctp_outq *q)
1065 {
1066 	q->cork = 1;
1067 }
1068 
1069 /* These bind address data fields common between endpoints and associations */
1070 struct sctp_bind_addr {
1071 
1072 	/* RFC 2960 12.1 Parameters necessary for the SCTP instance
1073 	 *
1074 	 * SCTP Port:	The local SCTP port number the endpoint is
1075 	 *		bound to.
1076 	 */
1077 	__u16 port;
1078 
1079 	/* RFC 2960 12.1 Parameters necessary for the SCTP instance
1080 	 *
1081 	 * Address List: The list of IP addresses that this instance
1082 	 *	has bound.  This information is passed to one's
1083 	 *	peer(s) in INIT and INIT ACK chunks.
1084 	 */
1085 	struct list_head address_list;
1086 };
1087 
1088 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1089 void sctp_bind_addr_free(struct sctp_bind_addr *);
1090 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest,
1091 			const struct sctp_bind_addr *src,
1092 			sctp_scope_t scope, gfp_t gfp,
1093 			int flags);
1094 int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
1095 			const struct sctp_bind_addr *src,
1096 			gfp_t gfp);
1097 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1098 		       __u8 addr_state, gfp_t gfp);
1099 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1100 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1101 			 struct sctp_sock *);
1102 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *,
1103 			 struct sctp_sock *, struct sctp_sock *);
1104 int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
1105 			 const union sctp_addr *addr);
1106 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr	*bp,
1107 					const union sctp_addr	*addrs,
1108 					int			addrcnt,
1109 					struct sctp_sock	*opt);
1110 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1111 					 int *addrs_len,
1112 					 gfp_t gfp);
1113 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1114 			   __u16 port, gfp_t gfp);
1115 
1116 sctp_scope_t sctp_scope(const union sctp_addr *);
1117 int sctp_in_scope(struct net *net, const union sctp_addr *addr, const sctp_scope_t scope);
1118 int sctp_is_any(struct sock *sk, const union sctp_addr *addr);
1119 int sctp_addr_is_valid(const union sctp_addr *addr);
1120 int sctp_is_ep_boundall(struct sock *sk);
1121 
1122 
1123 /* What type of endpoint?  */
1124 typedef enum {
1125 	SCTP_EP_TYPE_SOCKET,
1126 	SCTP_EP_TYPE_ASSOCIATION,
1127 } sctp_endpoint_type_t;
1128 
1129 /*
1130  * A common base class to bridge the implmentation view of a
1131  * socket (usually listening) endpoint versus an association's
1132  * local endpoint.
1133  * This common structure is useful for several purposes:
1134  *   1) Common interface for lookup routines.
1135  *	a) Subfunctions work for either endpoint or association
1136  *	b) Single interface to lookup allows hiding the lookup lock rather
1137  *	   than acquiring it externally.
1138  *   2) Common interface for the inbound chunk handling/state machine.
1139  *   3) Common object handling routines for reference counting, etc.
1140  *   4) Disentangle association lookup from endpoint lookup, where we
1141  *	do not have to find our endpoint to find our association.
1142  *
1143  */
1144 
1145 struct sctp_ep_common {
1146 	/* Fields to help us manage our entries in the hash tables. */
1147 	struct hlist_node node;
1148 	int hashent;
1149 
1150 	/* Runtime type information.  What kind of endpoint is this? */
1151 	sctp_endpoint_type_t type;
1152 
1153 	/* Some fields to help us manage this object.
1154 	 *   refcnt   - Reference count access to this object.
1155 	 *   dead     - Do not attempt to use this object.
1156 	 */
1157 	atomic_t    refcnt;
1158 	bool	    dead;
1159 
1160 	/* What socket does this endpoint belong to?  */
1161 	struct sock *sk;
1162 
1163 	/* This is where we receive inbound chunks.  */
1164 	struct sctp_inq	  inqueue;
1165 
1166 	/* This substructure includes the defining parameters of the
1167 	 * endpoint:
1168 	 * bind_addr.port is our shared port number.
1169 	 * bind_addr.address_list is our set of local IP addresses.
1170 	 */
1171 	struct sctp_bind_addr bind_addr;
1172 };
1173 
1174 
1175 /* RFC Section 1.4 Key Terms
1176  *
1177  * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1178  *   multi-homed host, an SCTP endpoint is represented to its peers as a
1179  *   combination of a set of eligible destination transport addresses to
1180  *   which SCTP packets can be sent and a set of eligible source
1181  *   transport addresses from which SCTP packets can be received.
1182  *   All transport addresses used by an SCTP endpoint must use the
1183  *   same port number, but can use multiple IP addresses. A transport
1184  *   address used by an SCTP endpoint must not be used by another
1185  *   SCTP endpoint. In other words, a transport address is unique
1186  *   to an SCTP endpoint.
1187  *
1188  * From an implementation perspective, each socket has one of these.
1189  * A TCP-style socket will have exactly one association on one of
1190  * these.  An UDP-style socket will have multiple associations hanging
1191  * off one of these.
1192  */
1193 
1194 struct sctp_endpoint {
1195 	/* Common substructure for endpoint and association. */
1196 	struct sctp_ep_common base;
1197 
1198 	/* Associations: A list of current associations and mappings
1199 	 *	      to the data consumers for each association. This
1200 	 *	      may be in the form of a hash table or other
1201 	 *	      implementation dependent structure. The data
1202 	 *	      consumers may be process identification
1203 	 *	      information such as file descriptors, named pipe
1204 	 *	      pointer, or table pointers dependent on how SCTP
1205 	 *	      is implemented.
1206 	 */
1207 	/* This is really a list of struct sctp_association entries. */
1208 	struct list_head asocs;
1209 
1210 	/* Secret Key: A secret key used by this endpoint to compute
1211 	 *	      the MAC.	This SHOULD be a cryptographic quality
1212 	 *	      random number with a sufficient length.
1213 	 *	      Discussion in [RFC1750] can be helpful in
1214 	 *	      selection of the key.
1215 	 */
1216 	__u8 secret_key[SCTP_SECRET_SIZE];
1217 
1218  	/* digest:  This is a digest of the sctp cookie.  This field is
1219  	 * 	    only used on the receive path when we try to validate
1220  	 * 	    that the cookie has not been tampered with.  We put
1221  	 * 	    this here so we pre-allocate this once and can re-use
1222  	 * 	    on every receive.
1223  	 */
1224  	__u8 *digest;
1225 
1226 	/* sendbuf acct. policy.	*/
1227 	__u32 sndbuf_policy;
1228 
1229 	/* rcvbuf acct. policy.	*/
1230 	__u32 rcvbuf_policy;
1231 
1232 	/* SCTP AUTH: array of the HMACs that will be allocated
1233 	 * we need this per association so that we don't serialize
1234 	 */
1235 	struct crypto_hash **auth_hmacs;
1236 
1237 	/* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1238 	 struct sctp_hmac_algo_param *auth_hmacs_list;
1239 
1240 	/* SCTP-AUTH: chunks to authenticate encoded into parameter */
1241 	struct sctp_chunks_param *auth_chunk_list;
1242 
1243 	/* SCTP-AUTH: endpoint shared keys */
1244 	struct list_head endpoint_shared_keys;
1245 	__u16 active_key_id;
1246 };
1247 
1248 /* Recover the outter endpoint structure. */
1249 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1250 {
1251 	struct sctp_endpoint *ep;
1252 
1253 	ep = container_of(base, struct sctp_endpoint, base);
1254 	return ep;
1255 }
1256 
1257 /* These are function signatures for manipulating endpoints.  */
1258 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1259 void sctp_endpoint_free(struct sctp_endpoint *);
1260 void sctp_endpoint_put(struct sctp_endpoint *);
1261 void sctp_endpoint_hold(struct sctp_endpoint *);
1262 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1263 struct sctp_association *sctp_endpoint_lookup_assoc(
1264 	const struct sctp_endpoint *ep,
1265 	const union sctp_addr *paddr,
1266 	struct sctp_transport **);
1267 int sctp_endpoint_is_peeled_off(struct sctp_endpoint *,
1268 				const union sctp_addr *);
1269 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1270 					struct net *, const union sctp_addr *);
1271 int sctp_has_association(struct net *net, const union sctp_addr *laddr,
1272 			 const union sctp_addr *paddr);
1273 
1274 int sctp_verify_init(struct net *net, const struct sctp_association *asoc,
1275 		     sctp_cid_t, sctp_init_chunk_t *peer_init,
1276 		     struct sctp_chunk *chunk, struct sctp_chunk **err_chunk);
1277 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk,
1278 		      const union sctp_addr *peer,
1279 		      sctp_init_chunk_t *init, gfp_t gfp);
1280 __u32 sctp_generate_tag(const struct sctp_endpoint *);
1281 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
1282 
1283 struct sctp_inithdr_host {
1284 	__u32 init_tag;
1285 	__u32 a_rwnd;
1286 	__u16 num_outbound_streams;
1287 	__u16 num_inbound_streams;
1288 	__u32 initial_tsn;
1289 };
1290 
1291 /* SCTP_GET_ASSOC_STATS counters */
1292 struct sctp_priv_assoc_stats {
1293 	/* Maximum observed rto in the association during subsequent
1294 	 * observations. Value is set to 0 if no RTO measurement took place
1295 	 * The transport where the max_rto was observed is returned in
1296 	 * obs_rto_ipaddr
1297 	 */
1298 	struct sockaddr_storage obs_rto_ipaddr;
1299 	__u64 max_obs_rto;
1300 	/* Total In and Out SACKs received and sent */
1301 	__u64 isacks;
1302 	__u64 osacks;
1303 	/* Total In and Out packets received and sent */
1304 	__u64 opackets;
1305 	__u64 ipackets;
1306 	/* Total retransmitted chunks */
1307 	__u64 rtxchunks;
1308 	/* TSN received > next expected */
1309 	__u64 outofseqtsns;
1310 	/* Duplicate Chunks received */
1311 	__u64 idupchunks;
1312 	/* Gap Ack Blocks received */
1313 	__u64 gapcnt;
1314 	/* Unordered data chunks sent and received */
1315 	__u64 ouodchunks;
1316 	__u64 iuodchunks;
1317 	/* Ordered data chunks sent and received */
1318 	__u64 oodchunks;
1319 	__u64 iodchunks;
1320 	/* Control chunks sent and received */
1321 	__u64 octrlchunks;
1322 	__u64 ictrlchunks;
1323 };
1324 
1325 /* RFC2960
1326  *
1327  * 12. Recommended Transmission Control Block (TCB) Parameters
1328  *
1329  * This section details a recommended set of parameters that should
1330  * be contained within the TCB for an implementation. This section is
1331  * for illustrative purposes and should not be deemed as requirements
1332  * on an implementation or as an exhaustive list of all parameters
1333  * inside an SCTP TCB. Each implementation may need its own additional
1334  * parameters for optimization.
1335  */
1336 
1337 
1338 /* Here we have information about each individual association. */
1339 struct sctp_association {
1340 
1341 	/* A base structure common to endpoint and association.
1342 	 * In this context, it represents the associations's view
1343 	 * of the local endpoint of the association.
1344 	 */
1345 	struct sctp_ep_common base;
1346 
1347 	/* Associations on the same socket. */
1348 	struct list_head asocs;
1349 
1350 	/* association id. */
1351 	sctp_assoc_t assoc_id;
1352 
1353 	/* This is our parent endpoint.	 */
1354 	struct sctp_endpoint *ep;
1355 
1356 	/* These are those association elements needed in the cookie.  */
1357 	struct sctp_cookie c;
1358 
1359 	/* This is all information about our peer.  */
1360 	struct {
1361 		/* rwnd
1362 		 *
1363 		 * Peer Rwnd   : Current calculated value of the peer's rwnd.
1364 		 */
1365 		__u32 rwnd;
1366 
1367 		/* transport_addr_list
1368 		 *
1369 		 * Peer	       : A list of SCTP transport addresses that the
1370 		 * Transport   : peer is bound to. This information is derived
1371 		 * Address     : from the INIT or INIT ACK and is used to
1372 		 * List	       : associate an inbound packet with a given
1373 		 *	       : association. Normally this information is
1374 		 *	       : hashed or keyed for quick lookup and access
1375 		 *	       : of the TCB.
1376 		 *	       : The list is also initialized with the list
1377 		 *	       : of addresses passed with the sctp_connectx()
1378 		 *	       : call.
1379 		 *
1380 		 * It is a list of SCTP_transport's.
1381 		 */
1382 		struct list_head transport_addr_list;
1383 
1384 		/* transport_count
1385 		 *
1386 		 * Peer        : A count of the number of peer addresses
1387 		 * Transport   : in the Peer Transport Address List.
1388 		 * Address     :
1389 		 * Count       :
1390 		 */
1391 		__u16 transport_count;
1392 
1393 		/* port
1394 		 *   The transport layer port number.
1395 		 */
1396 		__u16 port;
1397 
1398 		/* primary_path
1399 		 *
1400 		 * Primary     : This is the current primary destination
1401 		 * Path	       : transport address of the peer endpoint.  It
1402 		 *	       : may also specify a source transport address
1403 		 *	       : on this endpoint.
1404 		 *
1405 		 * All of these paths live on transport_addr_list.
1406 		 *
1407 		 * At the bakeoffs, we discovered that the intent of
1408 		 * primaryPath is that it only changes when the ULP
1409 		 * asks to have it changed.  We add the activePath to
1410 		 * designate the connection we are currently using to
1411 		 * transmit new data and most control chunks.
1412 		 */
1413 		struct sctp_transport *primary_path;
1414 
1415 		/* Cache the primary path address here, when we
1416 		 * need a an address for msg_name.
1417 		 */
1418 		union sctp_addr primary_addr;
1419 
1420 		/* active_path
1421 		 *   The path that we are currently using to
1422 		 *   transmit new data and most control chunks.
1423 		 */
1424 		struct sctp_transport *active_path;
1425 
1426 		/* retran_path
1427 		 *
1428 		 * RFC2960 6.4 Multi-homed SCTP Endpoints
1429 		 * ...
1430 		 * Furthermore, when its peer is multi-homed, an
1431 		 * endpoint SHOULD try to retransmit a chunk to an
1432 		 * active destination transport address that is
1433 		 * different from the last destination address to
1434 		 * which the DATA chunk was sent.
1435 		 */
1436 		struct sctp_transport *retran_path;
1437 
1438 		/* Pointer to last transport I have sent on.  */
1439 		struct sctp_transport *last_sent_to;
1440 
1441 		/* This is the last transport I have received DATA on.	*/
1442 		struct sctp_transport *last_data_from;
1443 
1444 		/*
1445 		 * Mapping  An array of bits or bytes indicating which out of
1446 		 * Array    order TSN's have been received (relative to the
1447 		 *	    Last Rcvd TSN). If no gaps exist, i.e. no out of
1448 		 *	    order packets have been received, this array
1449 		 *	    will be set to all zero. This structure may be
1450 		 *	    in the form of a circular buffer or bit array.
1451 		 *
1452 		 * Last Rcvd   : This is the last TSN received in
1453 		 * TSN	       : sequence. This value is set initially by
1454 		 *	       : taking the peer's Initial TSN, received in
1455 		 *	       : the INIT or INIT ACK chunk, and subtracting
1456 		 *	       : one from it.
1457 		 *
1458 		 * Throughout most of the specification this is called the
1459 		 * "Cumulative TSN ACK Point".	In this case, we
1460 		 * ignore the advice in 12.2 in favour of the term
1461 		 * used in the bulk of the text.  This value is hidden
1462 		 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1463 		 */
1464 		struct sctp_tsnmap tsn_map;
1465 
1466 		/* Ack State   : This flag indicates if the next received
1467 		 *             : packet is to be responded to with a
1468 		 *             : SACK. This is initializedto 0.  When a packet
1469 		 *             : is received it is incremented. If this value
1470 		 *             : reaches 2 or more, a SACK is sent and the
1471 		 *             : value is reset to 0. Note: This is used only
1472 		 *             : when no DATA chunks are received out of
1473 		 *             : order.  When DATA chunks are out of order,
1474 		 *             : SACK's are not delayed (see Section 6).
1475 		 */
1476 		__u8    sack_needed;     /* Do we need to sack the peer? */
1477 		__u32	sack_cnt;
1478 		__u32	sack_generation;
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 		__u32   adaptation_ind;	 /* Adaptation Code point. */
1490 
1491 		/* This mask is used to disable sending the ASCONF chunk
1492 		 * with specified parameter to peer.
1493 		 */
1494 		__be16 addip_disabled_mask;
1495 
1496 		struct sctp_inithdr_host i;
1497 		int cookie_len;
1498 		void *cookie;
1499 
1500 		/* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1501 		 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1502 		 * Initial TSN Value minus 1
1503 		 */
1504 		__u32 addip_serial;
1505 
1506 		/* SCTP-AUTH: We need to know pears random number, hmac list
1507 		 * and authenticated chunk list.  All that is part of the
1508 		 * cookie and these are just pointers to those locations
1509 		 */
1510 		sctp_random_param_t *peer_random;
1511 		sctp_chunks_param_t *peer_chunks;
1512 		sctp_hmac_algo_param_t *peer_hmacs;
1513 	} peer;
1514 
1515 	/* State       : A state variable indicating what state the
1516 	 *	       : association is in, i.e. COOKIE-WAIT,
1517 	 *	       : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1518 	 *	       : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1519 	 *
1520 	 *		Note: No "CLOSED" state is illustrated since if a
1521 	 *		association is "CLOSED" its TCB SHOULD be removed.
1522 	 *
1523 	 *		In this implementation we DO have a CLOSED
1524 	 *		state which is used during initiation and shutdown.
1525 	 *
1526 	 *		State takes values from SCTP_STATE_*.
1527 	 */
1528 	sctp_state_t state;
1529 
1530 	/* The cookie life I award for any cookie.  */
1531 	ktime_t cookie_life;
1532 
1533 	/* Overall     : The overall association error count.
1534 	 * Error Count : [Clear this any time I get something.]
1535 	 */
1536 	int overall_error_count;
1537 
1538 	/* These are the association's initial, max, and min RTO values.
1539 	 * These values will be initialized by system defaults, but can
1540 	 * be modified via the SCTP_RTOINFO socket option.
1541 	 */
1542 	unsigned long rto_initial;
1543 	unsigned long rto_max;
1544 	unsigned long rto_min;
1545 
1546 	/* Maximum number of new data packets that can be sent in a burst.  */
1547 	int max_burst;
1548 
1549 	/* This is the max_retrans value for the association.  This value will
1550 	 * be initialized initialized from system defaults, but can be
1551 	 * modified by the SCTP_ASSOCINFO socket option.
1552 	 */
1553 	int max_retrans;
1554 
1555 	/* This is the partially failed retrans value for the transport
1556 	 * and will be initialized from the assocs value.  This can be
1557 	 * changed using the SCTP_PEER_ADDR_THLDS socket option
1558 	 */
1559 	int pf_retrans;
1560 
1561 	/* Maximum number of times the endpoint will retransmit INIT  */
1562 	__u16 max_init_attempts;
1563 
1564 	/* How many times have we resent an INIT? */
1565 	__u16 init_retries;
1566 
1567 	/* The largest timeout or RTO value to use in attempting an INIT */
1568 	unsigned long max_init_timeo;
1569 
1570 	/* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1571 	 * the destination address every heartbeat interval. This value
1572 	 * will be inherited by all new transports.
1573 	 */
1574 	unsigned long hbinterval;
1575 
1576 	/* This is the max_retrans value for new transports in the
1577 	 * association.
1578 	 */
1579 	__u16 pathmaxrxt;
1580 
1581 	/* Flag that path mtu update is pending */
1582 	__u8   pmtu_pending;
1583 
1584 	/* Association : The smallest PMTU discovered for all of the
1585 	 * PMTU	       : peer's transport addresses.
1586 	 */
1587 	__u32 pathmtu;
1588 
1589 	/* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1590 	__u32 param_flags;
1591 
1592 	/* SACK delay timeout */
1593 	unsigned long sackdelay;
1594 	__u32 sackfreq;
1595 
1596 
1597 	unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES];
1598 	struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1599 
1600 	/* Transport to which SHUTDOWN chunk was last sent.  */
1601 	struct sctp_transport *shutdown_last_sent_to;
1602 
1603 	/* How many times have we resent a SHUTDOWN */
1604 	int shutdown_retries;
1605 
1606 	/* Transport to which INIT chunk was last sent.  */
1607 	struct sctp_transport *init_last_sent_to;
1608 
1609 	/* Next TSN    : The next TSN number to be assigned to a new
1610 	 *	       : DATA chunk.  This is sent in the INIT or INIT
1611 	 *	       : ACK chunk to the peer and incremented each
1612 	 *	       : time a DATA chunk is assigned a TSN
1613 	 *	       : (normally just prior to transmit or during
1614 	 *	       : fragmentation).
1615 	 */
1616 	__u32 next_tsn;
1617 
1618 	/*
1619 	 * Last Rcvd   : This is the last TSN received in sequence.  This value
1620 	 * TSN	       : is set initially by taking the peer's Initial TSN,
1621 	 *	       : received in the INIT or INIT ACK chunk, and
1622 	 *	       : subtracting one from it.
1623 	 *
1624 	 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1625 	 */
1626 
1627 	__u32 ctsn_ack_point;
1628 
1629 	/* PR-SCTP Advanced.Peer.Ack.Point */
1630 	__u32 adv_peer_ack_point;
1631 
1632 	/* Highest TSN that is acknowledged by incoming SACKs. */
1633 	__u32 highest_sacked;
1634 
1635 	/* TSN marking the fast recovery exit point */
1636 	__u32 fast_recovery_exit;
1637 
1638 	/* Flag to track the current fast recovery state */
1639 	__u8 fast_recovery;
1640 
1641 	/* The number of unacknowledged data chunks.  Reported through
1642 	 * the SCTP_STATUS sockopt.
1643 	 */
1644 	__u16 unack_data;
1645 
1646 	/* The total number of data chunks that we've had to retransmit
1647 	 * as the result of a T3 timer expiration
1648 	 */
1649 	__u32 rtx_data_chunks;
1650 
1651 	/* This is the association's receive buffer space.  This value is used
1652 	 * to set a_rwnd field in an INIT or a SACK chunk.
1653 	 */
1654 	__u32 rwnd;
1655 
1656 	/* This is the last advertised value of rwnd over a SACK chunk. */
1657 	__u32 a_rwnd;
1658 
1659 	/* Number of bytes by which the rwnd has slopped.  The rwnd is allowed
1660 	 * to slop over a maximum of the association's frag_point.
1661 	 */
1662 	__u32 rwnd_over;
1663 
1664 	/* Keeps treack of rwnd pressure.  This happens when we have
1665 	 * a window, but not recevie buffer (i.e small packets).  This one
1666 	 * is releases slowly (1 PMTU at a time ).
1667 	 */
1668 	__u32 rwnd_press;
1669 
1670 	/* This is the sndbuf size in use for the association.
1671 	 * This corresponds to the sndbuf size for the association,
1672 	 * as specified in the sk->sndbuf.
1673 	 */
1674 	int sndbuf_used;
1675 
1676 	/* This is the amount of memory that this association has allocated
1677 	 * in the receive path at any given time.
1678 	 */
1679 	atomic_t rmem_alloc;
1680 
1681 	/* This is the wait queue head for send requests waiting on
1682 	 * the association sndbuf space.
1683 	 */
1684 	wait_queue_head_t	wait;
1685 
1686 	/* The message size at which SCTP fragmentation will occur. */
1687 	__u32 frag_point;
1688 	__u32 user_frag;
1689 
1690 	/* Counter used to count INIT errors. */
1691 	int init_err_counter;
1692 
1693 	/* Count the number of INIT cycles (for doubling timeout). */
1694 	int init_cycle;
1695 
1696 	/* Default send parameters. */
1697 	__u16 default_stream;
1698 	__u16 default_flags;
1699 	__u32 default_ppid;
1700 	__u32 default_context;
1701 	__u32 default_timetolive;
1702 
1703 	/* Default receive parameters */
1704 	__u32 default_rcv_context;
1705 
1706 	/* This tracks outbound ssn for a given stream.	 */
1707 	struct sctp_ssnmap *ssnmap;
1708 
1709 	/* All outbound chunks go through this structure.  */
1710 	struct sctp_outq outqueue;
1711 
1712 	/* A smart pipe that will handle reordering and fragmentation,
1713 	 * as well as handle passing events up to the ULP.
1714 	 */
1715 	struct sctp_ulpq ulpq;
1716 
1717 	/* Last TSN that caused an ECNE Chunk to be sent.  */
1718 	__u32 last_ecne_tsn;
1719 
1720 	/* Last TSN that caused a CWR Chunk to be sent.	 */
1721 	__u32 last_cwr_tsn;
1722 
1723 	/* How many duplicated TSNs have we seen?  */
1724 	int numduptsns;
1725 
1726 	/* These are to support
1727 	 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1728 	 *  and Enforcement of Flow and Message Limits"
1729 	 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1730 	 * or "ADDIP" for short.
1731 	 */
1732 
1733 
1734 
1735 	/* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1736 	 *
1737 	 * R1) One and only one ASCONF Chunk MAY be in transit and
1738 	 * unacknowledged at any one time.  If a sender, after sending
1739 	 * an ASCONF chunk, decides it needs to transfer another
1740 	 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1741 	 * returns from the previous ASCONF Chunk before sending a
1742 	 * subsequent ASCONF. Note this restriction binds each side,
1743 	 * so at any time two ASCONF may be in-transit on any given
1744 	 * association (one sent from each endpoint).
1745 	 *
1746 	 * [This is our one-and-only-one ASCONF in flight.  If we do
1747 	 * not have an ASCONF in flight, this is NULL.]
1748 	 */
1749 	struct sctp_chunk *addip_last_asconf;
1750 
1751 	/* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
1752 	 *
1753 	 * This is needed to implement itmes E1 - E4 of the updated
1754 	 * spec.  Here is the justification:
1755 	 *
1756 	 * Since the peer may bundle multiple ASCONF chunks toward us,
1757 	 * we now need the ability to cache multiple ACKs.  The section
1758 	 * describes in detail how they are cached and cleaned up.
1759 	 */
1760 	struct list_head asconf_ack_list;
1761 
1762 	/* These ASCONF chunks are waiting to be sent.
1763 	 *
1764 	 * These chunaks can't be pushed to outqueue until receiving
1765 	 * ASCONF_ACK for the previous ASCONF indicated by
1766 	 * addip_last_asconf, so as to guarantee that only one ASCONF
1767 	 * is in flight at any time.
1768 	 *
1769 	 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1770 	 *
1771 	 * In defining the ASCONF Chunk transfer procedures, it is
1772 	 * essential that these transfers MUST NOT cause congestion
1773 	 * within the network.	To achieve this, we place these
1774 	 * restrictions on the transfer of ASCONF Chunks:
1775 	 *
1776 	 * R1) One and only one ASCONF Chunk MAY be in transit and
1777 	 * unacknowledged at any one time.  If a sender, after sending
1778 	 * an ASCONF chunk, decides it needs to transfer another
1779 	 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1780 	 * returns from the previous ASCONF Chunk before sending a
1781 	 * subsequent ASCONF. Note this restriction binds each side,
1782 	 * so at any time two ASCONF may be in-transit on any given
1783 	 * association (one sent from each endpoint).
1784 	 *
1785 	 *
1786 	 * [I really think this is EXACTLY the sort of intelligence
1787 	 *  which already resides in sctp_outq.	 Please move this
1788 	 *  queue and its supporting logic down there.	--piggy]
1789 	 */
1790 	struct list_head addip_chunk_list;
1791 
1792 	/* ADDIP Section 4.1 ASCONF Chunk Procedures
1793 	 *
1794 	 * A2) A serial number should be assigned to the Chunk. The
1795 	 * serial number SHOULD be a monotonically increasing
1796 	 * number. The serial number SHOULD be initialized at
1797 	 * the start of the association to the same value as the
1798 	 * Initial TSN and every time a new ASCONF chunk is created
1799 	 * it is incremented by one after assigning the serial number
1800 	 * to the newly created chunk.
1801 	 *
1802 	 * ADDIP
1803 	 * 3.1.1  Address/Stream Configuration Change Chunk (ASCONF)
1804 	 *
1805 	 * Serial Number : 32 bits (unsigned integer)
1806 	 *
1807 	 * This value represents a Serial Number for the ASCONF
1808 	 * Chunk. The valid range of Serial Number is from 0 to
1809 	 * 4294967295 (2^32 - 1).  Serial Numbers wrap back to 0
1810 	 * after reaching 4294967295.
1811 	 */
1812 	__u32 addip_serial;
1813 	union sctp_addr *asconf_addr_del_pending;
1814 	int src_out_of_asoc_ok;
1815 	struct sctp_transport *new_transport;
1816 
1817 	/* SCTP AUTH: list of the endpoint shared keys.  These
1818 	 * keys are provided out of band by the user applicaton
1819 	 * and can't change during the lifetime of the association
1820 	 */
1821 	struct list_head endpoint_shared_keys;
1822 
1823 	/* SCTP AUTH:
1824 	 * The current generated assocaition shared key (secret)
1825 	 */
1826 	struct sctp_auth_bytes *asoc_shared_key;
1827 
1828 	/* SCTP AUTH: hmac id of the first peer requested algorithm
1829 	 * that we support.
1830 	 */
1831 	__u16 default_hmac_id;
1832 
1833 	__u16 active_key_id;
1834 
1835 	__u8 need_ecne:1,	/* Need to send an ECNE Chunk? */
1836 	     temp:1;		/* Is it a temporary association? */
1837 
1838 	struct sctp_priv_assoc_stats stats;
1839 };
1840 
1841 
1842 /* An eyecatcher for determining if we are really looking at an
1843  * association data structure.
1844  */
1845 enum {
1846 	SCTP_ASSOC_EYECATCHER = 0xa550c123,
1847 };
1848 
1849 /* Recover the outter association structure. */
1850 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
1851 {
1852 	struct sctp_association *asoc;
1853 
1854 	asoc = container_of(base, struct sctp_association, base);
1855 	return asoc;
1856 }
1857 
1858 /* These are function signatures for manipulating associations.	 */
1859 
1860 
1861 struct sctp_association *
1862 sctp_association_new(const struct sctp_endpoint *, const struct sock *,
1863 		     sctp_scope_t scope, gfp_t gfp);
1864 void sctp_association_free(struct sctp_association *);
1865 void sctp_association_put(struct sctp_association *);
1866 void sctp_association_hold(struct sctp_association *);
1867 
1868 struct sctp_transport *sctp_assoc_choose_alter_transport(
1869 	struct sctp_association *, struct sctp_transport *);
1870 void sctp_assoc_update_retran_path(struct sctp_association *);
1871 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
1872 					  const union sctp_addr *);
1873 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1874 			    const union sctp_addr *laddr);
1875 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
1876 				     const union sctp_addr *address,
1877 				     const gfp_t gfp,
1878 				     const int peer_state);
1879 void sctp_assoc_del_peer(struct sctp_association *asoc,
1880 			 const union sctp_addr *addr);
1881 void sctp_assoc_rm_peer(struct sctp_association *asoc,
1882 			 struct sctp_transport *peer);
1883 void sctp_assoc_control_transport(struct sctp_association *,
1884 				  struct sctp_transport *,
1885 				  sctp_transport_cmd_t, sctp_sn_error_t);
1886 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
1887 struct sctp_transport *sctp_assoc_is_match(struct sctp_association *,
1888 					   struct net *,
1889 					   const union sctp_addr *,
1890 					   const union sctp_addr *);
1891 void sctp_assoc_migrate(struct sctp_association *, struct sock *);
1892 void sctp_assoc_update(struct sctp_association *old,
1893 		       struct sctp_association *new);
1894 
1895 __u32 sctp_association_get_next_tsn(struct sctp_association *);
1896 
1897 void sctp_assoc_sync_pmtu(struct sock *, struct sctp_association *);
1898 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int);
1899 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int);
1900 void sctp_assoc_set_primary(struct sctp_association *,
1901 			    struct sctp_transport *);
1902 void sctp_assoc_del_nonprimary_peers(struct sctp_association *,
1903 				    struct sctp_transport *);
1904 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *,
1905 				     sctp_scope_t, gfp_t);
1906 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
1907 					 struct sctp_cookie*,
1908 					 gfp_t gfp);
1909 int sctp_assoc_set_id(struct sctp_association *, gfp_t);
1910 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc);
1911 struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
1912 					const struct sctp_association *asoc,
1913 					__be32 serial);
1914 void sctp_asconf_queue_teardown(struct sctp_association *asoc);
1915 
1916 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1917 			const union sctp_addr *ss2);
1918 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
1919 
1920 /* A convenience structure to parse out SCTP specific CMSGs. */
1921 typedef struct sctp_cmsgs {
1922 	struct sctp_initmsg *init;
1923 	struct sctp_sndrcvinfo *info;
1924 } sctp_cmsgs_t;
1925 
1926 /* Structure for tracking memory objects */
1927 typedef struct {
1928 	char *label;
1929 	atomic_t *counter;
1930 } sctp_dbg_objcnt_entry_t;
1931 
1932 #endif /* __sctp_structs_h__ */
1933