1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* SCTP kernel implementation
3 * (C) Copyright IBM Corp. 2001, 2004
4 * Copyright (c) 1999-2000 Cisco, Inc.
5 * Copyright (c) 1999-2001 Motorola, Inc.
6 * Copyright (c) 2001 Intel Corp.
7 *
8 * This file is part of the SCTP kernel implementation
9 *
10 * Please send any bug reports or fixes you make to the
11 * email addresses:
12 * lksctp developers <linux-sctp@vger.kernel.org>
13 *
14 * Written or modified by:
15 * Randall Stewart <randall@sctp.chicago.il.us>
16 * Ken Morneau <kmorneau@cisco.com>
17 * Qiaobing Xie <qxie1@email.mot.com>
18 * La Monte H.P. Yarroll <piggy@acm.org>
19 * Karl Knutson <karl@athena.chicago.il.us>
20 * Jon Grimm <jgrimm@us.ibm.com>
21 * Xingang Guo <xingang.guo@intel.com>
22 * Hui Huang <hui.huang@nokia.com>
23 * Sridhar Samudrala <sri@us.ibm.com>
24 * Daisy Chang <daisyc@us.ibm.com>
25 * Dajiang Zhang <dajiang.zhang@nokia.com>
26 * Ardelle Fan <ardelle.fan@intel.com>
27 * Ryan Layer <rmlayer@us.ibm.com>
28 * Anup Pemmaiah <pemmaiah@cc.usu.edu>
29 * Kevin Gao <kevin.gao@intel.com>
30 */
31
32 #ifndef __sctp_structs_h__
33 #define __sctp_structs_h__
34
35 #include <linux/ktime.h>
36 #include <linux/generic-radix-tree.h>
37 #include <linux/rhashtable-types.h>
38 #include <linux/socket.h> /* linux/in.h needs this!! */
39 #include <linux/in.h> /* We get struct sockaddr_in. */
40 #include <linux/in6.h> /* We get struct in6_addr */
41 #include <linux/ipv6.h>
42 #include <asm/param.h> /* We get MAXHOSTNAMELEN. */
43 #include <linux/atomic.h> /* This gets us atomic counters. */
44 #include <linux/skbuff.h> /* We need sk_buff_head. */
45 #include <linux/workqueue.h> /* We need tq_struct. */
46 #include <linux/sctp.h> /* We need sctp* header structs. */
47 #include <net/sctp/auth.h> /* We need auth specific structs */
48 #include <net/ip.h> /* For inet_skb_parm */
49
50 /* A convenience structure for handling sockaddr structures.
51 * We should wean ourselves off this.
52 */
53 union sctp_addr {
54 struct sockaddr_in v4;
55 struct sockaddr_in6 v6;
56 struct sockaddr sa;
57 };
58
59 /* Forward declarations for data structures. */
60 struct sctp_globals;
61 struct sctp_endpoint;
62 struct sctp_association;
63 struct sctp_transport;
64 struct sctp_packet;
65 struct sctp_chunk;
66 struct sctp_inq;
67 struct sctp_outq;
68 struct sctp_bind_addr;
69 struct sctp_ulpq;
70 struct sctp_ep_common;
71 struct crypto_shash;
72 struct sctp_stream;
73
74
75 #include <net/sctp/tsnmap.h>
76 #include <net/sctp/ulpevent.h>
77 #include <net/sctp/ulpqueue.h>
78 #include <net/sctp/stream_interleave.h>
79
80 /* Structures useful for managing bind/connect. */
81
82 struct sctp_bind_bucket {
83 unsigned short port;
84 signed char fastreuse;
85 signed char fastreuseport;
86 kuid_t fastuid;
87 struct hlist_node node;
88 struct hlist_head owner;
89 struct net *net;
90 };
91
92 struct sctp_bind_hashbucket {
93 spinlock_t lock;
94 struct hlist_head chain;
95 };
96
97 /* Used for hashing all associations. */
98 struct sctp_hashbucket {
99 rwlock_t lock;
100 struct hlist_head chain;
101 } __attribute__((__aligned__(8)));
102
103
104 /* The SCTP globals structure. */
105 extern struct sctp_globals {
106 /* This is a list of groups of functions for each address
107 * family that we support.
108 */
109 struct list_head address_families;
110
111 /* This is the hash of all endpoints. */
112 struct sctp_hashbucket *ep_hashtable;
113 /* This is the sctp port control hash. */
114 struct sctp_bind_hashbucket *port_hashtable;
115 /* This is the hash of all transports. */
116 struct rhltable transport_hashtable;
117
118 /* Sizes of above hashtables. */
119 int ep_hashsize;
120 int port_hashsize;
121
122 /* Default initialization values to be applied to new associations. */
123 __u16 max_instreams;
124 __u16 max_outstreams;
125
126 /* Flag to indicate whether computing and verifying checksum
127 * is disabled. */
128 bool checksum_disable;
129 } sctp_globals;
130
131 #define sctp_max_instreams (sctp_globals.max_instreams)
132 #define sctp_max_outstreams (sctp_globals.max_outstreams)
133 #define sctp_address_families (sctp_globals.address_families)
134 #define sctp_ep_hashsize (sctp_globals.ep_hashsize)
135 #define sctp_ep_hashtable (sctp_globals.ep_hashtable)
136 #define sctp_port_hashsize (sctp_globals.port_hashsize)
137 #define sctp_port_hashtable (sctp_globals.port_hashtable)
138 #define sctp_transport_hashtable (sctp_globals.transport_hashtable)
139 #define sctp_checksum_disable (sctp_globals.checksum_disable)
140
141 /* SCTP Socket type: UDP or TCP style. */
142 enum sctp_socket_type {
143 SCTP_SOCKET_UDP = 0,
144 SCTP_SOCKET_UDP_HIGH_BANDWIDTH,
145 SCTP_SOCKET_TCP
146 };
147
148 /* Per socket SCTP information. */
149 struct sctp_sock {
150 /* inet_sock has to be the first member of sctp_sock */
151 struct inet_sock inet;
152 /* What kind of a socket is this? */
153 enum sctp_socket_type type;
154
155 /* PF_ family specific functions. */
156 struct sctp_pf *pf;
157
158 /* Access to HMAC transform. */
159 struct crypto_shash *hmac;
160 char *sctp_hmac_alg;
161
162 /* What is our base endpointer? */
163 struct sctp_endpoint *ep;
164
165 struct sctp_bind_bucket *bind_hash;
166 /* Various Socket Options. */
167 __u16 default_stream;
168 __u32 default_ppid;
169 __u16 default_flags;
170 __u32 default_context;
171 __u32 default_timetolive;
172 __u32 default_rcv_context;
173 int max_burst;
174
175 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
176 * the destination address every heartbeat interval. This value
177 * will be inherited by all new associations.
178 */
179 __u32 hbinterval;
180
181 /* This is the max_retrans value for new associations. */
182 __u16 pathmaxrxt;
183
184 __u32 flowlabel;
185 __u8 dscp;
186
187 int pf_retrans;
188
189 /* The initial Path MTU to use for new associations. */
190 __u32 pathmtu;
191
192 /* The default SACK delay timeout for new associations. */
193 __u32 sackdelay;
194 __u32 sackfreq;
195
196 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
197 __u32 param_flags;
198
199 __u32 default_ss;
200
201 struct sctp_rtoinfo rtoinfo;
202 struct sctp_paddrparams paddrparam;
203 struct sctp_assocparams assocparams;
204
205 /*
206 * These two structures must be grouped together for the usercopy
207 * whitelist region.
208 */
209 __u16 subscribe;
210 struct sctp_initmsg initmsg;
211
212 int user_frag;
213
214 __u32 autoclose;
215 __u32 adaptation_ind;
216 __u32 pd_point;
217 __u16 nodelay:1,
218 reuse:1,
219 disable_fragments:1,
220 v4mapped:1,
221 frag_interleave:1,
222 recvrcvinfo:1,
223 recvnxtinfo:1,
224 data_ready_signalled:1;
225
226 atomic_t pd_mode;
227 /* Receive to here while partial delivery is in effect. */
228 struct sk_buff_head pd_lobby;
229
230 /* These must be the last fields, as they will skipped on copies,
231 * like on accept and peeloff operations
232 */
233 struct list_head auto_asconf_list;
234 int do_auto_asconf;
235 };
236
sctp_sk(const struct sock * sk)237 static inline struct sctp_sock *sctp_sk(const struct sock *sk)
238 {
239 return (struct sctp_sock *)sk;
240 }
241
sctp_opt2sk(const struct sctp_sock * sp)242 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
243 {
244 return (struct sock *)sp;
245 }
246
247 #if IS_ENABLED(CONFIG_IPV6)
248 struct sctp6_sock {
249 struct sctp_sock sctp;
250 struct ipv6_pinfo inet6;
251 };
252 #endif /* CONFIG_IPV6 */
253
254
255 /* This is our APPLICATION-SPECIFIC state cookie.
256 * THIS IS NOT DICTATED BY THE SPECIFICATION.
257 */
258 /* These are the parts of an association which we send in the cookie.
259 * Most of these are straight out of:
260 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
261 *
262 */
263
264 struct sctp_cookie {
265
266 /* My : Tag expected in every inbound packet and sent
267 * Verification: in the INIT or INIT ACK chunk.
268 * Tag :
269 */
270 __u32 my_vtag;
271
272 /* Peer's : Tag expected in every outbound packet except
273 * Verification: in the INIT chunk.
274 * Tag :
275 */
276 __u32 peer_vtag;
277
278 /* The rest of these are not from the spec, but really need to
279 * be in the cookie.
280 */
281
282 /* My Tie Tag : Assist in discovering a restarting association. */
283 __u32 my_ttag;
284
285 /* Peer's Tie Tag: Assist in discovering a restarting association. */
286 __u32 peer_ttag;
287
288 /* When does this cookie expire? */
289 ktime_t expiration;
290
291 /* Number of inbound/outbound streams which are set
292 * and negotiated during the INIT process.
293 */
294 __u16 sinit_num_ostreams;
295 __u16 sinit_max_instreams;
296
297 /* This is the first sequence number I used. */
298 __u32 initial_tsn;
299
300 /* This holds the originating address of the INIT packet. */
301 union sctp_addr peer_addr;
302
303 /* IG Section 2.35.3
304 * Include the source port of the INIT-ACK
305 */
306 __u16 my_port;
307
308 __u8 prsctp_capable;
309
310 /* Padding for future use */
311 __u8 padding;
312
313 __u32 adaptation_ind;
314
315 __u8 auth_random[sizeof(struct sctp_paramhdr) +
316 SCTP_AUTH_RANDOM_LENGTH];
317 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2];
318 __u8 auth_chunks[sizeof(struct sctp_paramhdr) + SCTP_AUTH_MAX_CHUNKS];
319
320 /* This is a shim for my peer's INIT packet, followed by
321 * a copy of the raw address list of the association.
322 * The length of the raw address list is saved in the
323 * raw_addr_list_len field, which will be used at the time when
324 * the association TCB is re-constructed from the cookie.
325 */
326 __u32 raw_addr_list_len;
327 struct sctp_init_chunk peer_init[0];
328 };
329
330
331 /* The format of our cookie that we send to our peer. */
332 struct sctp_signed_cookie {
333 __u8 signature[SCTP_SECRET_SIZE];
334 __u32 __pad; /* force sctp_cookie alignment to 64 bits */
335 struct sctp_cookie c;
336 } __packed;
337
338 /* This is another convenience type to allocate memory for address
339 * params for the maximum size and pass such structures around
340 * internally.
341 */
342 union sctp_addr_param {
343 struct sctp_paramhdr p;
344 struct sctp_ipv4addr_param v4;
345 struct sctp_ipv6addr_param v6;
346 };
347
348 /* A convenience type to allow walking through the various
349 * parameters and avoid casting all over the place.
350 */
351 union sctp_params {
352 void *v;
353 struct sctp_paramhdr *p;
354 struct sctp_cookie_preserve_param *life;
355 struct sctp_hostname_param *dns;
356 struct sctp_cookie_param *cookie;
357 struct sctp_supported_addrs_param *sat;
358 struct sctp_ipv4addr_param *v4;
359 struct sctp_ipv6addr_param *v6;
360 union sctp_addr_param *addr;
361 struct sctp_adaptation_ind_param *aind;
362 struct sctp_supported_ext_param *ext;
363 struct sctp_random_param *random;
364 struct sctp_chunks_param *chunks;
365 struct sctp_hmac_algo_param *hmac_algo;
366 struct sctp_addip_param *addip;
367 };
368
369 /* RFC 2960. Section 3.3.5 Heartbeat.
370 * Heartbeat Information: variable length
371 * The Sender-specific Heartbeat Info field should normally include
372 * information about the sender's current time when this HEARTBEAT
373 * chunk is sent and the destination transport address to which this
374 * HEARTBEAT is sent (see Section 8.3).
375 */
376 struct sctp_sender_hb_info {
377 struct sctp_paramhdr param_hdr;
378 union sctp_addr daddr;
379 unsigned long sent_at;
380 __u64 hb_nonce;
381 };
382
383 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt,
384 gfp_t gfp);
385 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid);
386 void sctp_stream_free(struct sctp_stream *stream);
387 void sctp_stream_clear(struct sctp_stream *stream);
388 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new);
389
390 /* What is the current SSN number for this stream? */
391 #define sctp_ssn_peek(stream, type, sid) \
392 (sctp_stream_##type((stream), (sid))->ssn)
393
394 /* Return the next SSN number for this stream. */
395 #define sctp_ssn_next(stream, type, sid) \
396 (sctp_stream_##type((stream), (sid))->ssn++)
397
398 /* Skip over this ssn and all below. */
399 #define sctp_ssn_skip(stream, type, sid, ssn) \
400 (sctp_stream_##type((stream), (sid))->ssn = ssn + 1)
401
402 /* What is the current MID number for this stream? */
403 #define sctp_mid_peek(stream, type, sid) \
404 (sctp_stream_##type((stream), (sid))->mid)
405
406 /* Return the next MID number for this stream. */
407 #define sctp_mid_next(stream, type, sid) \
408 (sctp_stream_##type((stream), (sid))->mid++)
409
410 /* Skip over this mid and all below. */
411 #define sctp_mid_skip(stream, type, sid, mid) \
412 (sctp_stream_##type((stream), (sid))->mid = mid + 1)
413
414 /* What is the current MID_uo number for this stream? */
415 #define sctp_mid_uo_peek(stream, type, sid) \
416 (sctp_stream_##type((stream), (sid))->mid_uo)
417
418 /* Return the next MID_uo number for this stream. */
419 #define sctp_mid_uo_next(stream, type, sid) \
420 (sctp_stream_##type((stream), (sid))->mid_uo++)
421
422 /*
423 * Pointers to address related SCTP functions.
424 * (i.e. things that depend on the address family.)
425 */
426 struct sctp_af {
427 int (*sctp_xmit) (struct sk_buff *skb,
428 struct sctp_transport *);
429 int (*setsockopt) (struct sock *sk,
430 int level,
431 int optname,
432 char __user *optval,
433 unsigned int optlen);
434 int (*getsockopt) (struct sock *sk,
435 int level,
436 int optname,
437 char __user *optval,
438 int __user *optlen);
439 int (*compat_setsockopt) (struct sock *sk,
440 int level,
441 int optname,
442 char __user *optval,
443 unsigned int optlen);
444 int (*compat_getsockopt) (struct sock *sk,
445 int level,
446 int optname,
447 char __user *optval,
448 int __user *optlen);
449 void (*get_dst) (struct sctp_transport *t,
450 union sctp_addr *saddr,
451 struct flowi *fl,
452 struct sock *sk);
453 void (*get_saddr) (struct sctp_sock *sk,
454 struct sctp_transport *t,
455 struct flowi *fl);
456 void (*copy_addrlist) (struct list_head *,
457 struct net_device *);
458 int (*cmp_addr) (const union sctp_addr *addr1,
459 const union sctp_addr *addr2);
460 void (*addr_copy) (union sctp_addr *dst,
461 union sctp_addr *src);
462 void (*from_skb) (union sctp_addr *,
463 struct sk_buff *skb,
464 int saddr);
465 void (*from_sk) (union sctp_addr *,
466 struct sock *sk);
467 void (*from_addr_param) (union sctp_addr *,
468 union sctp_addr_param *,
469 __be16 port, int iif);
470 int (*to_addr_param) (const union sctp_addr *,
471 union sctp_addr_param *);
472 int (*addr_valid) (union sctp_addr *,
473 struct sctp_sock *,
474 const struct sk_buff *);
475 enum sctp_scope (*scope)(union sctp_addr *);
476 void (*inaddr_any) (union sctp_addr *, __be16);
477 int (*is_any) (const union sctp_addr *);
478 int (*available) (union sctp_addr *,
479 struct sctp_sock *);
480 int (*skb_iif) (const struct sk_buff *sk);
481 int (*is_ce) (const struct sk_buff *sk);
482 void (*seq_dump_addr)(struct seq_file *seq,
483 union sctp_addr *addr);
484 void (*ecn_capable)(struct sock *sk);
485 __u16 net_header_len;
486 int sockaddr_len;
487 int (*ip_options_len)(struct sock *sk);
488 sa_family_t sa_family;
489 struct list_head list;
490 };
491
492 struct sctp_af *sctp_get_af_specific(sa_family_t);
493 int sctp_register_af(struct sctp_af *);
494
495 /* Protocol family functions. */
496 struct sctp_pf {
497 void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
498 void (*skb_msgname) (struct sk_buff *, char *, int *);
499 int (*af_supported) (sa_family_t, struct sctp_sock *);
500 int (*cmp_addr) (const union sctp_addr *,
501 const union sctp_addr *,
502 struct sctp_sock *);
503 int (*bind_verify) (struct sctp_sock *, union sctp_addr *);
504 int (*send_verify) (struct sctp_sock *, union sctp_addr *);
505 int (*supported_addrs)(const struct sctp_sock *, __be16 *);
506 struct sock *(*create_accept_sk) (struct sock *sk,
507 struct sctp_association *asoc,
508 bool kern);
509 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr);
510 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk);
511 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk);
512 void (*copy_ip_options)(struct sock *sk, struct sock *newsk);
513 struct sctp_af *af;
514 };
515
516
517 /* Structure to track chunk fragments that have been acked, but peer
518 * fragments of the same message have not.
519 */
520 struct sctp_datamsg {
521 /* Chunks waiting to be submitted to lower layer. */
522 struct list_head chunks;
523 /* Reference counting. */
524 refcount_t refcnt;
525 /* When is this message no longer interesting to the peer? */
526 unsigned long expires_at;
527 /* Did the messenge fail to send? */
528 int send_error;
529 u8 send_failed:1,
530 can_delay:1, /* should this message be Nagle delayed */
531 abandoned:1; /* should this message be abandoned */
532 };
533
534 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
535 struct sctp_sndrcvinfo *,
536 struct iov_iter *);
537 void sctp_datamsg_free(struct sctp_datamsg *);
538 void sctp_datamsg_put(struct sctp_datamsg *);
539 void sctp_chunk_fail(struct sctp_chunk *, int error);
540 int 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 */
550 struct sctp_chunk {
551 struct list_head list;
552
553 refcount_t refcnt;
554
555 /* How many times this chunk have been sent, for prsctp RTX policy */
556 int sent_count;
557
558 union {
559 /* This is our link to the per-transport transmitted list. */
560 struct list_head transmitted_list;
561 /* List in specific stream outq */
562 struct list_head stream_list;
563 };
564
565 /* This field is used by chunks that hold fragmented data.
566 * For the first fragment this is the list that holds the rest of
567 * fragments. For the remaining fragments, this is the link to the
568 * frag_list maintained in the first fragment.
569 */
570 struct list_head frag_list;
571
572 /* This points to the sk_buff containing the actual data. */
573 struct sk_buff *skb;
574
575 union {
576 /* In case of GSO packets, this will store the head one */
577 struct sk_buff *head_skb;
578 /* In case of auth enabled, this will point to the shkey */
579 struct sctp_shared_key *shkey;
580 };
581
582 /* These are the SCTP headers by reverse order in a packet.
583 * Note that some of these may happen more than once. In that
584 * case, we point at the "current" one, whatever that means
585 * for that level of header.
586 */
587
588 /* We point this at the FIRST TLV parameter to chunk_hdr. */
589 union sctp_params param_hdr;
590 union {
591 __u8 *v;
592 struct sctp_datahdr *data_hdr;
593 struct sctp_inithdr *init_hdr;
594 struct sctp_sackhdr *sack_hdr;
595 struct sctp_heartbeathdr *hb_hdr;
596 struct sctp_sender_hb_info *hbs_hdr;
597 struct sctp_shutdownhdr *shutdown_hdr;
598 struct sctp_signed_cookie *cookie_hdr;
599 struct sctp_ecnehdr *ecne_hdr;
600 struct sctp_cwrhdr *ecn_cwr_hdr;
601 struct sctp_errhdr *err_hdr;
602 struct sctp_addiphdr *addip_hdr;
603 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
604 struct sctp_authhdr *auth_hdr;
605 struct sctp_idatahdr *idata_hdr;
606 struct sctp_ifwdtsn_hdr *ifwdtsn_hdr;
607 } subh;
608
609 __u8 *chunk_end;
610
611 struct sctp_chunkhdr *chunk_hdr;
612 struct sctphdr *sctp_hdr;
613
614 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
615 struct sctp_sndrcvinfo sinfo;
616
617 /* Which association does this belong to? */
618 struct sctp_association *asoc;
619
620 /* What endpoint received this chunk? */
621 struct sctp_ep_common *rcvr;
622
623 /* We fill this in if we are calculating RTT. */
624 unsigned long sent_at;
625
626 /* What is the origin IP address for this chunk? */
627 union sctp_addr source;
628 /* Destination address for this chunk. */
629 union sctp_addr dest;
630
631 /* For outbound message, track all fragments for SEND_FAILED. */
632 struct sctp_datamsg *msg;
633
634 /* For an inbound chunk, this tells us where it came from.
635 * For an outbound chunk, it tells us where we'd like it to
636 * go. It is NULL if we have no preference.
637 */
638 struct sctp_transport *transport;
639
640 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO
641 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
642 * spec violates the principle premis that all chunks are processed
643 * in order.
644 */
645 struct sk_buff *auth_chunk;
646
647 #define SCTP_CAN_FRTX 0x0
648 #define SCTP_NEED_FRTX 0x1
649 #define SCTP_DONT_FRTX 0x2
650 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */
651 has_tsn:1, /* Does this chunk have a TSN yet? */
652 has_ssn:1, /* Does this chunk have a SSN yet? */
653 #define has_mid has_ssn
654 singleton:1, /* Only chunk in the packet? */
655 end_of_packet:1, /* Last chunk in the packet? */
656 ecn_ce_done:1, /* Have we processed the ECN CE bit? */
657 pdiscard:1, /* Discard the whole packet now? */
658 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */
659 data_accepted:1, /* At least 1 chunk accepted */
660 auth:1, /* IN: was auth'ed | OUT: needs auth */
661 has_asconf:1, /* IN: have seen an asconf before */
662 tsn_missing_report:2, /* Data chunk missing counter. */
663 fast_retransmit:2; /* Is this chunk fast retransmitted? */
664 };
665
666 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1)
667 void sctp_chunk_hold(struct sctp_chunk *);
668 void sctp_chunk_put(struct sctp_chunk *);
669 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len,
670 struct iov_iter *from);
671 void sctp_chunk_free(struct sctp_chunk *);
672 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
673 struct sctp_chunk *sctp_chunkify(struct sk_buff *,
674 const struct sctp_association *,
675 struct sock *, gfp_t gfp);
676 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
677 union sctp_addr *);
678 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
679
sctp_chunk_stream_no(struct sctp_chunk * ch)680 static inline __u16 sctp_chunk_stream_no(struct sctp_chunk *ch)
681 {
682 return ntohs(ch->subh.data_hdr->stream);
683 }
684
685 enum {
686 SCTP_ADDR_NEW, /* new address added to assoc/ep */
687 SCTP_ADDR_SRC, /* address can be used as source */
688 SCTP_ADDR_DEL, /* address about to be deleted */
689 };
690
691 /* This is a structure for holding either an IPv6 or an IPv4 address. */
692 struct sctp_sockaddr_entry {
693 struct list_head list;
694 struct rcu_head rcu;
695 union sctp_addr a;
696 __u8 state;
697 __u8 valid;
698 };
699
700 #define SCTP_ADDRESS_TICK_DELAY 500
701
702 /* This structure holds lists of chunks as we are assembling for
703 * transmission.
704 */
705 struct sctp_packet {
706 /* These are the SCTP header values (host order) for the packet. */
707 __u16 source_port;
708 __u16 destination_port;
709 __u32 vtag;
710
711 /* This contains the payload chunks. */
712 struct list_head chunk_list;
713
714 /* This is the overhead of the sctp and ip headers. */
715 size_t overhead;
716 /* This is the total size of all chunks INCLUDING padding. */
717 size_t size;
718 /* This is the maximum size this packet may have */
719 size_t max_size;
720
721 /* The packet is destined for this transport address.
722 * The function we finally use to pass down to the next lower
723 * layer lives in the transport structure.
724 */
725 struct sctp_transport *transport;
726
727 /* pointer to the auth chunk for this packet */
728 struct sctp_chunk *auth;
729
730 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */
731 has_sack:1, /* This packet contains a SACK chunk. */
732 has_auth:1, /* This packet contains an AUTH chunk */
733 has_data:1, /* This packet contains at least 1 DATA chunk */
734 ipfragok:1; /* So let ip fragment this packet */
735 };
736
737 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *,
738 __u16 sport, __u16 dport);
739 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
740 enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet,
741 struct sctp_chunk *chunk,
742 int one_packet, gfp_t gfp);
743 enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet,
744 struct sctp_chunk *chunk);
745 int sctp_packet_transmit(struct sctp_packet *, gfp_t);
746 void sctp_packet_free(struct sctp_packet *);
747
sctp_packet_empty(struct sctp_packet * packet)748 static inline int sctp_packet_empty(struct sctp_packet *packet)
749 {
750 return packet->size == packet->overhead;
751 }
752
753 /* This represents a remote transport address.
754 * For local transport addresses, we just use union sctp_addr.
755 *
756 * RFC2960 Section 1.4 Key Terms
757 *
758 * o Transport address: A Transport Address is traditionally defined
759 * by Network Layer address, Transport Layer protocol and Transport
760 * Layer port number. In the case of SCTP running over IP, a
761 * transport address is defined by the combination of an IP address
762 * and an SCTP port number (where SCTP is the Transport protocol).
763 *
764 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
765 *
766 * o The sender keeps a separate congestion control parameter set for
767 * each of the destination addresses it can send to (not each
768 * source-destination pair but for each destination). The parameters
769 * should decay if the address is not used for a long enough time
770 * period.
771 *
772 */
773 struct sctp_transport {
774 /* A list of transports. */
775 struct list_head transports;
776 struct rhlist_head node;
777
778 /* Reference counting. */
779 refcount_t refcnt;
780 /* RTO-Pending : A flag used to track if one of the DATA
781 * chunks sent to this address is currently being
782 * used to compute a RTT. If this flag is 0,
783 * the next DATA chunk sent to this destination
784 * should be used to compute a RTT and this flag
785 * should be set. Every time the RTT
786 * calculation completes (i.e. the DATA chunk
787 * is SACK'd) clear this flag.
788 */
789 __u32 rto_pending:1,
790
791 /*
792 * hb_sent : a flag that signals that we have a pending
793 * heartbeat.
794 */
795 hb_sent:1,
796
797 /* Is the Path MTU update pending on this tranport */
798 pmtu_pending:1,
799
800 dst_pending_confirm:1, /* need to confirm neighbour */
801
802 /* Has this transport moved the ctsn since we last sacked */
803 sack_generation:1;
804 u32 dst_cookie;
805
806 struct flowi fl;
807
808 /* This is the peer's IP address and port. */
809 union sctp_addr ipaddr;
810
811 /* These are the functions we call to handle LLP stuff. */
812 struct sctp_af *af_specific;
813
814 /* Which association do we belong to? */
815 struct sctp_association *asoc;
816
817 /* RFC2960
818 *
819 * 12.3 Per Transport Address Data
820 *
821 * For each destination transport address in the peer's
822 * address list derived from the INIT or INIT ACK chunk, a
823 * number of data elements needs to be maintained including:
824 */
825 /* RTO : The current retransmission timeout value. */
826 unsigned long rto;
827
828 __u32 rtt; /* This is the most recent RTT. */
829
830 /* RTTVAR : The current RTT variation. */
831 __u32 rttvar;
832
833 /* SRTT : The current smoothed round trip time. */
834 __u32 srtt;
835
836 /*
837 * These are the congestion stats.
838 */
839 /* cwnd : The current congestion window. */
840 __u32 cwnd; /* This is the actual cwnd. */
841
842 /* ssthresh : The current slow start threshold value. */
843 __u32 ssthresh;
844
845 /* partial : The tracking method for increase of cwnd when in
846 * bytes acked : congestion avoidance mode (see Section 6.2.2)
847 */
848 __u32 partial_bytes_acked;
849
850 /* Data that has been sent, but not acknowledged. */
851 __u32 flight_size;
852
853 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */
854
855 /* Destination */
856 struct dst_entry *dst;
857 /* Source address. */
858 union sctp_addr saddr;
859
860 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
861 * the destination address every heartbeat interval.
862 */
863 unsigned long hbinterval;
864
865 /* SACK delay timeout */
866 unsigned long sackdelay;
867 __u32 sackfreq;
868
869 atomic_t mtu_info;
870
871 /* When was the last time that we heard from this transport? We use
872 * this to pick new active and retran paths.
873 */
874 ktime_t last_time_heard;
875
876 /* When was the last time that we sent a chunk using this
877 * transport? We use this to check for idle transports
878 */
879 unsigned long last_time_sent;
880
881 /* Last time(in jiffies) when cwnd is reduced due to the congestion
882 * indication based on ECNE chunk.
883 */
884 unsigned long last_time_ecne_reduced;
885
886 /* This is the max_retrans value for the transport and will
887 * be initialized from the assocs value. This can be changed
888 * using the SCTP_SET_PEER_ADDR_PARAMS socket option.
889 */
890 __u16 pathmaxrxt;
891
892 __u32 flowlabel;
893 __u8 dscp;
894
895 /* This is the partially failed retrans value for the transport
896 * and will be initialized from the assocs value. This can be changed
897 * using the SCTP_PEER_ADDR_THLDS socket option
898 */
899 int pf_retrans;
900 /* PMTU : The current known path MTU. */
901 __u32 pathmtu;
902
903 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
904 __u32 param_flags;
905
906 /* The number of times INIT has been sent on this transport. */
907 int init_sent_count;
908
909 /* state : The current state of this destination,
910 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
911 */
912 int state;
913
914 /* These are the error stats for this destination. */
915
916 /* Error count : The current error count for this destination. */
917 unsigned short error_count;
918
919 /* Per : A timer used by each destination.
920 * Destination :
921 * Timer :
922 *
923 * [Everywhere else in the text this is called T3-rtx. -ed]
924 */
925 struct timer_list T3_rtx_timer;
926
927 /* Heartbeat timer is per destination. */
928 struct timer_list hb_timer;
929
930 /* Timer to handle ICMP proto unreachable envets */
931 struct timer_list proto_unreach_timer;
932
933 /* Timer to handler reconf chunk rtx */
934 struct timer_list reconf_timer;
935
936 /* Since we're using per-destination retransmission timers
937 * (see above), we're also using per-destination "transmitted"
938 * queues. This probably ought to be a private struct
939 * accessible only within the outqueue, but it's not, yet.
940 */
941 struct list_head transmitted;
942
943 /* We build bundle-able packets for this transport here. */
944 struct sctp_packet packet;
945
946 /* This is the list of transports that have chunks to send. */
947 struct list_head send_ready;
948
949 /* State information saved for SFR_CACC algorithm. The key
950 * idea in SFR_CACC is to maintain state at the sender on a
951 * per-destination basis when a changeover happens.
952 * char changeover_active;
953 * char cycling_changeover;
954 * __u32 next_tsn_at_change;
955 * char cacc_saw_newack;
956 */
957 struct {
958 /* An unsigned integer, which stores the next TSN to be
959 * used by the sender, at the moment of changeover.
960 */
961 __u32 next_tsn_at_change;
962
963 /* A flag which indicates the occurrence of a changeover */
964 char changeover_active;
965
966 /* A flag which indicates whether the change of primary is
967 * the first switch to this destination address during an
968 * active switch.
969 */
970 char cycling_changeover;
971
972 /* A temporary flag, which is used during the processing of
973 * a SACK to estimate the causative TSN(s)'s group.
974 */
975 char cacc_saw_newack;
976 } cacc;
977
978 /* 64-bit random number sent with heartbeat. */
979 __u64 hb_nonce;
980
981 struct rcu_head rcu;
982 };
983
984 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *,
985 gfp_t);
986 void sctp_transport_set_owner(struct sctp_transport *,
987 struct sctp_association *);
988 void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
989 struct sctp_sock *);
990 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk);
991 void sctp_transport_free(struct sctp_transport *);
992 void sctp_transport_reset_t3_rtx(struct sctp_transport *);
993 void sctp_transport_reset_hb_timer(struct sctp_transport *);
994 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport);
995 int sctp_transport_hold(struct sctp_transport *);
996 void sctp_transport_put(struct sctp_transport *);
997 void sctp_transport_update_rto(struct sctp_transport *, __u32);
998 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
999 void sctp_transport_lower_cwnd(struct sctp_transport *t,
1000 enum sctp_lower_cwnd reason);
1001 void sctp_transport_burst_limited(struct sctp_transport *);
1002 void sctp_transport_burst_reset(struct sctp_transport *);
1003 unsigned long sctp_transport_timeout(struct sctp_transport *);
1004 void sctp_transport_reset(struct sctp_transport *t);
1005 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu);
1006 void sctp_transport_immediate_rtx(struct sctp_transport *);
1007 void sctp_transport_dst_release(struct sctp_transport *t);
1008 void sctp_transport_dst_confirm(struct sctp_transport *t);
1009
1010
1011 /* This is the structure we use to queue packets as they come into
1012 * SCTP. We write packets to it and read chunks from it.
1013 */
1014 struct sctp_inq {
1015 /* This is actually a queue of sctp_chunk each
1016 * containing a partially decoded packet.
1017 */
1018 struct list_head in_chunk_list;
1019 /* This is the packet which is currently off the in queue and is
1020 * being worked on through the inbound chunk processing.
1021 */
1022 struct sctp_chunk *in_progress;
1023
1024 /* This is the delayed task to finish delivering inbound
1025 * messages.
1026 */
1027 struct work_struct immediate;
1028 };
1029
1030 void sctp_inq_init(struct sctp_inq *);
1031 void sctp_inq_free(struct sctp_inq *);
1032 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
1033 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
1034 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *);
1035 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t);
1036
1037 /* This is the structure we use to hold outbound chunks. You push
1038 * chunks in and they automatically pop out the other end as bundled
1039 * packets (it calls (*output_handler)()).
1040 *
1041 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1042 * and 8.2 of the v13 draft.
1043 *
1044 * It handles retransmissions. The connection to the timeout portion
1045 * of the state machine is through sctp_..._timeout() and timeout_handler.
1046 *
1047 * If you feed it SACKs, it will eat them.
1048 *
1049 * If you give it big chunks, it will fragment them.
1050 *
1051 * It assigns TSN's to data chunks. This happens at the last possible
1052 * instant before transmission.
1053 *
1054 * When free()'d, it empties itself out via output_handler().
1055 */
1056 struct sctp_outq {
1057 struct sctp_association *asoc;
1058
1059 /* Data pending that has never been transmitted. */
1060 struct list_head out_chunk_list;
1061
1062 /* Stream scheduler being used */
1063 struct sctp_sched_ops *sched;
1064
1065 unsigned int out_qlen; /* Total length of queued data chunks. */
1066
1067 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1068 unsigned int error;
1069
1070 /* These are control chunks we want to send. */
1071 struct list_head control_chunk_list;
1072
1073 /* These are chunks that have been sacked but are above the
1074 * CTSN, or cumulative tsn ack point.
1075 */
1076 struct list_head sacked;
1077
1078 /* Put chunks on this list to schedule them for
1079 * retransmission.
1080 */
1081 struct list_head retransmit;
1082
1083 /* Put chunks on this list to save them for FWD TSN processing as
1084 * they were abandoned.
1085 */
1086 struct list_head abandoned;
1087
1088 /* How many unackd bytes do we have in-flight? */
1089 __u32 outstanding_bytes;
1090
1091 /* Are we doing fast-rtx on this queue */
1092 char fast_rtx;
1093
1094 /* Corked? */
1095 char cork;
1096 };
1097
1098 void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1099 void sctp_outq_teardown(struct sctp_outq *);
1100 void sctp_outq_free(struct sctp_outq*);
1101 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t);
1102 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *);
1103 int sctp_outq_is_empty(const struct sctp_outq *);
1104 void sctp_outq_restart(struct sctp_outq *);
1105
1106 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport,
1107 enum sctp_retransmit_reason reason);
1108 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1109 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp);
1110 void sctp_prsctp_prune(struct sctp_association *asoc,
1111 struct sctp_sndrcvinfo *sinfo, int msg_len);
1112 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn);
1113 /* Uncork and flush an outqueue. */
sctp_outq_cork(struct sctp_outq * q)1114 static inline void sctp_outq_cork(struct sctp_outq *q)
1115 {
1116 q->cork = 1;
1117 }
1118
1119 /* SCTP skb control block.
1120 * sctp_input_cb is currently used on rx and sock rx queue
1121 */
1122 struct sctp_input_cb {
1123 union {
1124 struct inet_skb_parm h4;
1125 #if IS_ENABLED(CONFIG_IPV6)
1126 struct inet6_skb_parm h6;
1127 #endif
1128 } header;
1129 struct sctp_chunk *chunk;
1130 struct sctp_af *af;
1131 };
1132 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0]))
1133
1134 struct sctp_output_cb {
1135 struct sk_buff *last;
1136 };
1137 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0]))
1138
sctp_gso_headskb(const struct sk_buff * skb)1139 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb)
1140 {
1141 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk;
1142
1143 return chunk->head_skb ? : skb;
1144 }
1145
1146 /* These bind address data fields common between endpoints and associations */
1147 struct sctp_bind_addr {
1148
1149 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1150 *
1151 * SCTP Port: The local SCTP port number the endpoint is
1152 * bound to.
1153 */
1154 __u16 port;
1155
1156 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1157 *
1158 * Address List: The list of IP addresses that this instance
1159 * has bound. This information is passed to one's
1160 * peer(s) in INIT and INIT ACK chunks.
1161 */
1162 struct list_head address_list;
1163 };
1164
1165 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1166 void sctp_bind_addr_free(struct sctp_bind_addr *);
1167 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest,
1168 const struct sctp_bind_addr *src,
1169 enum sctp_scope scope, gfp_t gfp,
1170 int flags);
1171 int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
1172 const struct sctp_bind_addr *src,
1173 gfp_t gfp);
1174 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1175 int new_size, __u8 addr_state, gfp_t gfp);
1176 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1177 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1178 struct sctp_sock *);
1179 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *,
1180 struct sctp_sock *, struct sctp_sock *);
1181 int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
1182 const union sctp_addr *addr);
1183 int sctp_bind_addrs_check(struct sctp_sock *sp,
1184 struct sctp_sock *sp2, int cnt2);
1185 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp,
1186 const union sctp_addr *addrs,
1187 int addrcnt,
1188 struct sctp_sock *opt);
1189 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1190 int *addrs_len,
1191 gfp_t gfp);
1192 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1193 __u16 port, gfp_t gfp);
1194
1195 enum sctp_scope sctp_scope(const union sctp_addr *addr);
1196 int sctp_in_scope(struct net *net, const union sctp_addr *addr,
1197 const enum sctp_scope scope);
1198 int sctp_is_any(struct sock *sk, const union sctp_addr *addr);
1199 int sctp_is_ep_boundall(struct sock *sk);
1200
1201
1202 /* What type of endpoint? */
1203 enum sctp_endpoint_type {
1204 SCTP_EP_TYPE_SOCKET,
1205 SCTP_EP_TYPE_ASSOCIATION,
1206 };
1207
1208 /*
1209 * A common base class to bridge the implmentation view of a
1210 * socket (usually listening) endpoint versus an association's
1211 * local endpoint.
1212 * This common structure is useful for several purposes:
1213 * 1) Common interface for lookup routines.
1214 * a) Subfunctions work for either endpoint or association
1215 * b) Single interface to lookup allows hiding the lookup lock rather
1216 * than acquiring it externally.
1217 * 2) Common interface for the inbound chunk handling/state machine.
1218 * 3) Common object handling routines for reference counting, etc.
1219 * 4) Disentangle association lookup from endpoint lookup, where we
1220 * do not have to find our endpoint to find our association.
1221 *
1222 */
1223
1224 struct sctp_ep_common {
1225 /* Fields to help us manage our entries in the hash tables. */
1226 struct hlist_node node;
1227 int hashent;
1228
1229 /* Runtime type information. What kind of endpoint is this? */
1230 enum sctp_endpoint_type type;
1231
1232 /* Some fields to help us manage this object.
1233 * refcnt - Reference count access to this object.
1234 * dead - Do not attempt to use this object.
1235 */
1236 refcount_t refcnt;
1237 bool dead;
1238
1239 /* What socket does this endpoint belong to? */
1240 struct sock *sk;
1241
1242 /* This is where we receive inbound chunks. */
1243 struct sctp_inq inqueue;
1244
1245 /* This substructure includes the defining parameters of the
1246 * endpoint:
1247 * bind_addr.port is our shared port number.
1248 * bind_addr.address_list is our set of local IP addresses.
1249 */
1250 struct sctp_bind_addr bind_addr;
1251 };
1252
1253
1254 /* RFC Section 1.4 Key Terms
1255 *
1256 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1257 * multi-homed host, an SCTP endpoint is represented to its peers as a
1258 * combination of a set of eligible destination transport addresses to
1259 * which SCTP packets can be sent and a set of eligible source
1260 * transport addresses from which SCTP packets can be received.
1261 * All transport addresses used by an SCTP endpoint must use the
1262 * same port number, but can use multiple IP addresses. A transport
1263 * address used by an SCTP endpoint must not be used by another
1264 * SCTP endpoint. In other words, a transport address is unique
1265 * to an SCTP endpoint.
1266 *
1267 * From an implementation perspective, each socket has one of these.
1268 * A TCP-style socket will have exactly one association on one of
1269 * these. An UDP-style socket will have multiple associations hanging
1270 * off one of these.
1271 */
1272
1273 struct sctp_endpoint {
1274 /* Common substructure for endpoint and association. */
1275 struct sctp_ep_common base;
1276
1277 /* Associations: A list of current associations and mappings
1278 * to the data consumers for each association. This
1279 * may be in the form of a hash table or other
1280 * implementation dependent structure. The data
1281 * consumers may be process identification
1282 * information such as file descriptors, named pipe
1283 * pointer, or table pointers dependent on how SCTP
1284 * is implemented.
1285 */
1286 /* This is really a list of struct sctp_association entries. */
1287 struct list_head asocs;
1288
1289 /* Secret Key: A secret key used by this endpoint to compute
1290 * the MAC. This SHOULD be a cryptographic quality
1291 * random number with a sufficient length.
1292 * Discussion in [RFC1750] can be helpful in
1293 * selection of the key.
1294 */
1295 __u8 secret_key[SCTP_SECRET_SIZE];
1296
1297 /* digest: This is a digest of the sctp cookie. This field is
1298 * only used on the receive path when we try to validate
1299 * that the cookie has not been tampered with. We put
1300 * this here so we pre-allocate this once and can re-use
1301 * on every receive.
1302 */
1303 __u8 *digest;
1304
1305 /* sendbuf acct. policy. */
1306 __u32 sndbuf_policy;
1307
1308 /* rcvbuf acct. policy. */
1309 __u32 rcvbuf_policy;
1310
1311 /* SCTP AUTH: array of the HMACs that will be allocated
1312 * we need this per association so that we don't serialize
1313 */
1314 struct crypto_shash **auth_hmacs;
1315
1316 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1317 struct sctp_hmac_algo_param *auth_hmacs_list;
1318
1319 /* SCTP-AUTH: chunks to authenticate encoded into parameter */
1320 struct sctp_chunks_param *auth_chunk_list;
1321
1322 /* SCTP-AUTH: endpoint shared keys */
1323 struct list_head endpoint_shared_keys;
1324 __u16 active_key_id;
1325 __u8 ecn_enable:1,
1326 auth_enable:1,
1327 intl_enable:1,
1328 prsctp_enable:1,
1329 asconf_enable:1,
1330 reconf_enable:1;
1331
1332 __u8 strreset_enable;
1333
1334 /* Security identifiers from incoming (INIT). These are set by
1335 * security_sctp_assoc_request(). These will only be used by
1336 * SCTP TCP type sockets and peeled off connections as they
1337 * cause a new socket to be generated. security_sctp_sk_clone()
1338 * will then plug these into the new socket.
1339 */
1340
1341 u32 secid;
1342 u32 peer_secid;
1343 };
1344
1345 /* Recover the outter endpoint structure. */
sctp_ep(struct sctp_ep_common * base)1346 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1347 {
1348 struct sctp_endpoint *ep;
1349
1350 ep = container_of(base, struct sctp_endpoint, base);
1351 return ep;
1352 }
1353
1354 /* These are function signatures for manipulating endpoints. */
1355 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1356 void sctp_endpoint_free(struct sctp_endpoint *);
1357 void sctp_endpoint_put(struct sctp_endpoint *);
1358 void sctp_endpoint_hold(struct sctp_endpoint *);
1359 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1360 struct sctp_association *sctp_endpoint_lookup_assoc(
1361 const struct sctp_endpoint *ep,
1362 const union sctp_addr *paddr,
1363 struct sctp_transport **);
1364 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep,
1365 const union sctp_addr *paddr);
1366 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1367 struct net *, const union sctp_addr *);
1368 bool sctp_has_association(struct net *net, const union sctp_addr *laddr,
1369 const union sctp_addr *paddr);
1370
1371 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep,
1372 const struct sctp_association *asoc,
1373 enum sctp_cid cid, struct sctp_init_chunk *peer_init,
1374 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk);
1375 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk,
1376 const union sctp_addr *peer,
1377 struct sctp_init_chunk *init, gfp_t gfp);
1378 __u32 sctp_generate_tag(const struct sctp_endpoint *);
1379 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
1380
1381 struct sctp_inithdr_host {
1382 __u32 init_tag;
1383 __u32 a_rwnd;
1384 __u16 num_outbound_streams;
1385 __u16 num_inbound_streams;
1386 __u32 initial_tsn;
1387 };
1388
1389 struct sctp_stream_priorities {
1390 /* List of priorities scheduled */
1391 struct list_head prio_sched;
1392 /* List of streams scheduled */
1393 struct list_head active;
1394 /* The next stream stream in line */
1395 struct sctp_stream_out_ext *next;
1396 __u16 prio;
1397 };
1398
1399 struct sctp_stream_out_ext {
1400 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1];
1401 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1];
1402 struct list_head outq; /* chunks enqueued by this stream */
1403 union {
1404 struct {
1405 /* Scheduled streams list */
1406 struct list_head prio_list;
1407 struct sctp_stream_priorities *prio_head;
1408 };
1409 /* Fields used by RR scheduler */
1410 struct {
1411 struct list_head rr_list;
1412 };
1413 };
1414 };
1415
1416 struct sctp_stream_out {
1417 union {
1418 __u32 mid;
1419 __u16 ssn;
1420 };
1421 __u32 mid_uo;
1422 struct sctp_stream_out_ext *ext;
1423 __u8 state;
1424 };
1425
1426 struct sctp_stream_in {
1427 union {
1428 __u32 mid;
1429 __u16 ssn;
1430 };
1431 __u32 mid_uo;
1432 __u32 fsn;
1433 __u32 fsn_uo;
1434 char pd_mode;
1435 char pd_mode_uo;
1436 };
1437
1438 struct sctp_stream {
1439 GENRADIX(struct sctp_stream_out) out;
1440 GENRADIX(struct sctp_stream_in) in;
1441
1442 __u16 outcnt;
1443 __u16 incnt;
1444 /* Current stream being sent, if any */
1445 struct sctp_stream_out *out_curr;
1446 union {
1447 /* Fields used by priority scheduler */
1448 struct {
1449 /* List of priorities scheduled */
1450 struct list_head prio_list;
1451 };
1452 /* Fields used by RR scheduler */
1453 struct {
1454 /* List of streams scheduled */
1455 struct list_head rr_list;
1456 /* The next stream stream in line */
1457 struct sctp_stream_out_ext *rr_next;
1458 };
1459 };
1460 struct sctp_stream_interleave *si;
1461 };
1462
sctp_stream_out(struct sctp_stream * stream,__u16 sid)1463 static inline struct sctp_stream_out *sctp_stream_out(
1464 struct sctp_stream *stream,
1465 __u16 sid)
1466 {
1467 return genradix_ptr(&stream->out, sid);
1468 }
1469
sctp_stream_in(struct sctp_stream * stream,__u16 sid)1470 static inline struct sctp_stream_in *sctp_stream_in(
1471 struct sctp_stream *stream,
1472 __u16 sid)
1473 {
1474 return genradix_ptr(&stream->in, sid);
1475 }
1476
1477 #define SCTP_SO(s, i) sctp_stream_out((s), (i))
1478 #define SCTP_SI(s, i) sctp_stream_in((s), (i))
1479
1480 #define SCTP_STREAM_CLOSED 0x00
1481 #define SCTP_STREAM_OPEN 0x01
1482
sctp_datachk_len(const struct sctp_stream * stream)1483 static inline __u16 sctp_datachk_len(const struct sctp_stream *stream)
1484 {
1485 return stream->si->data_chunk_len;
1486 }
1487
sctp_datahdr_len(const struct sctp_stream * stream)1488 static inline __u16 sctp_datahdr_len(const struct sctp_stream *stream)
1489 {
1490 return stream->si->data_chunk_len - sizeof(struct sctp_chunkhdr);
1491 }
1492
sctp_ftsnchk_len(const struct sctp_stream * stream)1493 static inline __u16 sctp_ftsnchk_len(const struct sctp_stream *stream)
1494 {
1495 return stream->si->ftsn_chunk_len;
1496 }
1497
sctp_ftsnhdr_len(const struct sctp_stream * stream)1498 static inline __u16 sctp_ftsnhdr_len(const struct sctp_stream *stream)
1499 {
1500 return stream->si->ftsn_chunk_len - sizeof(struct sctp_chunkhdr);
1501 }
1502
1503 /* SCTP_GET_ASSOC_STATS counters */
1504 struct sctp_priv_assoc_stats {
1505 /* Maximum observed rto in the association during subsequent
1506 * observations. Value is set to 0 if no RTO measurement took place
1507 * The transport where the max_rto was observed is returned in
1508 * obs_rto_ipaddr
1509 */
1510 struct sockaddr_storage obs_rto_ipaddr;
1511 __u64 max_obs_rto;
1512 /* Total In and Out SACKs received and sent */
1513 __u64 isacks;
1514 __u64 osacks;
1515 /* Total In and Out packets received and sent */
1516 __u64 opackets;
1517 __u64 ipackets;
1518 /* Total retransmitted chunks */
1519 __u64 rtxchunks;
1520 /* TSN received > next expected */
1521 __u64 outofseqtsns;
1522 /* Duplicate Chunks received */
1523 __u64 idupchunks;
1524 /* Gap Ack Blocks received */
1525 __u64 gapcnt;
1526 /* Unordered data chunks sent and received */
1527 __u64 ouodchunks;
1528 __u64 iuodchunks;
1529 /* Ordered data chunks sent and received */
1530 __u64 oodchunks;
1531 __u64 iodchunks;
1532 /* Control chunks sent and received */
1533 __u64 octrlchunks;
1534 __u64 ictrlchunks;
1535 };
1536
1537 /* RFC2960
1538 *
1539 * 12. Recommended Transmission Control Block (TCB) Parameters
1540 *
1541 * This section details a recommended set of parameters that should
1542 * be contained within the TCB for an implementation. This section is
1543 * for illustrative purposes and should not be deemed as requirements
1544 * on an implementation or as an exhaustive list of all parameters
1545 * inside an SCTP TCB. Each implementation may need its own additional
1546 * parameters for optimization.
1547 */
1548
1549
1550 /* Here we have information about each individual association. */
1551 struct sctp_association {
1552
1553 /* A base structure common to endpoint and association.
1554 * In this context, it represents the associations's view
1555 * of the local endpoint of the association.
1556 */
1557 struct sctp_ep_common base;
1558
1559 /* Associations on the same socket. */
1560 struct list_head asocs;
1561
1562 /* association id. */
1563 sctp_assoc_t assoc_id;
1564
1565 /* This is our parent endpoint. */
1566 struct sctp_endpoint *ep;
1567
1568 /* These are those association elements needed in the cookie. */
1569 struct sctp_cookie c;
1570
1571 /* This is all information about our peer. */
1572 struct {
1573 /* transport_addr_list
1574 *
1575 * Peer : A list of SCTP transport addresses that the
1576 * Transport : peer is bound to. This information is derived
1577 * Address : from the INIT or INIT ACK and is used to
1578 * List : associate an inbound packet with a given
1579 * : association. Normally this information is
1580 * : hashed or keyed for quick lookup and access
1581 * : of the TCB.
1582 * : The list is also initialized with the list
1583 * : of addresses passed with the sctp_connectx()
1584 * : call.
1585 *
1586 * It is a list of SCTP_transport's.
1587 */
1588 struct list_head transport_addr_list;
1589
1590 /* rwnd
1591 *
1592 * Peer Rwnd : Current calculated value of the peer's rwnd.
1593 */
1594 __u32 rwnd;
1595
1596 /* transport_count
1597 *
1598 * Peer : A count of the number of peer addresses
1599 * Transport : in the Peer Transport Address List.
1600 * Address :
1601 * Count :
1602 */
1603 __u16 transport_count;
1604
1605 /* port
1606 * The transport layer port number.
1607 */
1608 __u16 port;
1609
1610 /* primary_path
1611 *
1612 * Primary : This is the current primary destination
1613 * Path : transport address of the peer endpoint. It
1614 * : may also specify a source transport address
1615 * : on this endpoint.
1616 *
1617 * All of these paths live on transport_addr_list.
1618 *
1619 * At the bakeoffs, we discovered that the intent of
1620 * primaryPath is that it only changes when the ULP
1621 * asks to have it changed. We add the activePath to
1622 * designate the connection we are currently using to
1623 * transmit new data and most control chunks.
1624 */
1625 struct sctp_transport *primary_path;
1626
1627 /* Cache the primary path address here, when we
1628 * need a an address for msg_name.
1629 */
1630 union sctp_addr primary_addr;
1631
1632 /* active_path
1633 * The path that we are currently using to
1634 * transmit new data and most control chunks.
1635 */
1636 struct sctp_transport *active_path;
1637
1638 /* retran_path
1639 *
1640 * RFC2960 6.4 Multi-homed SCTP Endpoints
1641 * ...
1642 * Furthermore, when its peer is multi-homed, an
1643 * endpoint SHOULD try to retransmit a chunk to an
1644 * active destination transport address that is
1645 * different from the last destination address to
1646 * which the DATA chunk was sent.
1647 */
1648 struct sctp_transport *retran_path;
1649
1650 /* Pointer to last transport I have sent on. */
1651 struct sctp_transport *last_sent_to;
1652
1653 /* This is the last transport I have received DATA on. */
1654 struct sctp_transport *last_data_from;
1655
1656 /*
1657 * Mapping An array of bits or bytes indicating which out of
1658 * Array order TSN's have been received (relative to the
1659 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1660 * order packets have been received, this array
1661 * will be set to all zero. This structure may be
1662 * in the form of a circular buffer or bit array.
1663 *
1664 * Last Rcvd : This is the last TSN received in
1665 * TSN : sequence. This value is set initially by
1666 * : taking the peer's Initial TSN, received in
1667 * : the INIT or INIT ACK chunk, and subtracting
1668 * : one from it.
1669 *
1670 * Throughout most of the specification this is called the
1671 * "Cumulative TSN ACK Point". In this case, we
1672 * ignore the advice in 12.2 in favour of the term
1673 * used in the bulk of the text. This value is hidden
1674 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1675 */
1676 struct sctp_tsnmap tsn_map;
1677
1678 /* This mask is used to disable sending the ASCONF chunk
1679 * with specified parameter to peer.
1680 */
1681 __be16 addip_disabled_mask;
1682
1683 /* These are capabilities which our peer advertised. */
1684 __u16 ecn_capable:1, /* Can peer do ECN? */
1685 ipv4_address:1, /* Peer understands IPv4 addresses? */
1686 ipv6_address:1, /* Peer understands IPv6 addresses? */
1687 hostname_address:1, /* Peer understands DNS addresses? */
1688 asconf_capable:1, /* Does peer support ADDIP? */
1689 prsctp_capable:1, /* Can peer do PR-SCTP? */
1690 reconf_capable:1, /* Can peer do RE-CONFIG? */
1691 intl_capable:1, /* Can peer do INTERLEAVE */
1692 auth_capable:1, /* Is peer doing SCTP-AUTH? */
1693 /* sack_needed:
1694 * This flag indicates if the next received
1695 * packet is to be responded to with a
1696 * SACK. This is initialized to 0. When a packet
1697 * is received sack_cnt is incremented. If this value
1698 * reaches 2 or more, a SACK is sent and the
1699 * value is reset to 0. Note: This is used only
1700 * when no DATA chunks are received out of
1701 * order. When DATA chunks are out of order,
1702 * SACK's are not delayed (see Section 6).
1703 */
1704 sack_needed:1, /* Do we need to sack the peer? */
1705 sack_generation:1,
1706 zero_window_announced:1;
1707
1708 __u32 sack_cnt;
1709
1710 __u32 adaptation_ind; /* Adaptation Code point. */
1711
1712 struct sctp_inithdr_host i;
1713 void *cookie;
1714 int cookie_len;
1715
1716 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1717 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1718 * Initial TSN Value minus 1
1719 */
1720 __u32 addip_serial;
1721
1722 /* SCTP-AUTH: We need to know pears random number, hmac list
1723 * and authenticated chunk list. All that is part of the
1724 * cookie and these are just pointers to those locations
1725 */
1726 struct sctp_random_param *peer_random;
1727 struct sctp_chunks_param *peer_chunks;
1728 struct sctp_hmac_algo_param *peer_hmacs;
1729 } peer;
1730
1731 /* State : A state variable indicating what state the
1732 * : association is in, i.e. COOKIE-WAIT,
1733 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1734 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1735 *
1736 * Note: No "CLOSED" state is illustrated since if a
1737 * association is "CLOSED" its TCB SHOULD be removed.
1738 *
1739 * In this implementation we DO have a CLOSED
1740 * state which is used during initiation and shutdown.
1741 *
1742 * State takes values from SCTP_STATE_*.
1743 */
1744 enum sctp_state state;
1745
1746 /* Overall : The overall association error count.
1747 * Error Count : [Clear this any time I get something.]
1748 */
1749 int overall_error_count;
1750
1751 /* The cookie life I award for any cookie. */
1752 ktime_t cookie_life;
1753
1754 /* These are the association's initial, max, and min RTO values.
1755 * These values will be initialized by system defaults, but can
1756 * be modified via the SCTP_RTOINFO socket option.
1757 */
1758 unsigned long rto_initial;
1759 unsigned long rto_max;
1760 unsigned long rto_min;
1761
1762 /* Maximum number of new data packets that can be sent in a burst. */
1763 int max_burst;
1764
1765 /* This is the max_retrans value for the association. This value will
1766 * be initialized initialized from system defaults, but can be
1767 * modified by the SCTP_ASSOCINFO socket option.
1768 */
1769 int max_retrans;
1770
1771 /* This is the partially failed retrans value for the transport
1772 * and will be initialized from the assocs value. This can be
1773 * changed using the SCTP_PEER_ADDR_THLDS socket option
1774 */
1775 int pf_retrans;
1776
1777 /* Maximum number of times the endpoint will retransmit INIT */
1778 __u16 max_init_attempts;
1779
1780 /* How many times have we resent an INIT? */
1781 __u16 init_retries;
1782
1783 /* The largest timeout or RTO value to use in attempting an INIT */
1784 unsigned long max_init_timeo;
1785
1786 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1787 * the destination address every heartbeat interval. This value
1788 * will be inherited by all new transports.
1789 */
1790 unsigned long hbinterval;
1791
1792 /* This is the max_retrans value for new transports in the
1793 * association.
1794 */
1795 __u16 pathmaxrxt;
1796
1797 __u32 flowlabel;
1798 __u8 dscp;
1799
1800 /* Flag that path mtu update is pending */
1801 __u8 pmtu_pending;
1802
1803 /* Association : The smallest PMTU discovered for all of the
1804 * PMTU : peer's transport addresses.
1805 */
1806 __u32 pathmtu;
1807
1808 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1809 __u32 param_flags;
1810
1811 __u32 sackfreq;
1812 /* SACK delay timeout */
1813 unsigned long sackdelay;
1814
1815 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES];
1816 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1817
1818 /* Transport to which SHUTDOWN chunk was last sent. */
1819 struct sctp_transport *shutdown_last_sent_to;
1820
1821 /* Transport to which INIT chunk was last sent. */
1822 struct sctp_transport *init_last_sent_to;
1823
1824 /* How many times have we resent a SHUTDOWN */
1825 int shutdown_retries;
1826
1827 /* Next TSN : The next TSN number to be assigned to a new
1828 * : DATA chunk. This is sent in the INIT or INIT
1829 * : ACK chunk to the peer and incremented each
1830 * : time a DATA chunk is assigned a TSN
1831 * : (normally just prior to transmit or during
1832 * : fragmentation).
1833 */
1834 __u32 next_tsn;
1835
1836 /*
1837 * Last Rcvd : This is the last TSN received in sequence. This value
1838 * TSN : is set initially by taking the peer's Initial TSN,
1839 * : received in the INIT or INIT ACK chunk, and
1840 * : subtracting one from it.
1841 *
1842 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1843 */
1844
1845 __u32 ctsn_ack_point;
1846
1847 /* PR-SCTP Advanced.Peer.Ack.Point */
1848 __u32 adv_peer_ack_point;
1849
1850 /* Highest TSN that is acknowledged by incoming SACKs. */
1851 __u32 highest_sacked;
1852
1853 /* TSN marking the fast recovery exit point */
1854 __u32 fast_recovery_exit;
1855
1856 /* Flag to track the current fast recovery state */
1857 __u8 fast_recovery;
1858
1859 /* The number of unacknowledged data chunks. Reported through
1860 * the SCTP_STATUS sockopt.
1861 */
1862 __u16 unack_data;
1863
1864 /* The total number of data chunks that we've had to retransmit
1865 * as the result of a T3 timer expiration
1866 */
1867 __u32 rtx_data_chunks;
1868
1869 /* This is the association's receive buffer space. This value is used
1870 * to set a_rwnd field in an INIT or a SACK chunk.
1871 */
1872 __u32 rwnd;
1873
1874 /* This is the last advertised value of rwnd over a SACK chunk. */
1875 __u32 a_rwnd;
1876
1877 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1878 * to slop over a maximum of the association's frag_point.
1879 */
1880 __u32 rwnd_over;
1881
1882 /* Keeps treack of rwnd pressure. This happens when we have
1883 * a window, but not recevie buffer (i.e small packets). This one
1884 * is releases slowly (1 PMTU at a time ).
1885 */
1886 __u32 rwnd_press;
1887
1888 /* This is the sndbuf size in use for the association.
1889 * This corresponds to the sndbuf size for the association,
1890 * as specified in the sk->sndbuf.
1891 */
1892 int sndbuf_used;
1893
1894 /* This is the amount of memory that this association has allocated
1895 * in the receive path at any given time.
1896 */
1897 atomic_t rmem_alloc;
1898
1899 /* This is the wait queue head for send requests waiting on
1900 * the association sndbuf space.
1901 */
1902 wait_queue_head_t wait;
1903
1904 /* The message size at which SCTP fragmentation will occur. */
1905 __u32 frag_point;
1906 __u32 user_frag;
1907
1908 /* Counter used to count INIT errors. */
1909 int init_err_counter;
1910
1911 /* Count the number of INIT cycles (for doubling timeout). */
1912 int init_cycle;
1913
1914 /* Default send parameters. */
1915 __u16 default_stream;
1916 __u16 default_flags;
1917 __u32 default_ppid;
1918 __u32 default_context;
1919 __u32 default_timetolive;
1920
1921 /* Default receive parameters */
1922 __u32 default_rcv_context;
1923
1924 /* Stream arrays */
1925 struct sctp_stream stream;
1926
1927 /* All outbound chunks go through this structure. */
1928 struct sctp_outq outqueue;
1929
1930 /* A smart pipe that will handle reordering and fragmentation,
1931 * as well as handle passing events up to the ULP.
1932 */
1933 struct sctp_ulpq ulpq;
1934
1935 /* Last TSN that caused an ECNE Chunk to be sent. */
1936 __u32 last_ecne_tsn;
1937
1938 /* Last TSN that caused a CWR Chunk to be sent. */
1939 __u32 last_cwr_tsn;
1940
1941 /* How many duplicated TSNs have we seen? */
1942 int numduptsns;
1943
1944 /* These are to support
1945 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1946 * and Enforcement of Flow and Message Limits"
1947 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1948 * or "ADDIP" for short.
1949 */
1950
1951
1952
1953 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1954 *
1955 * R1) One and only one ASCONF Chunk MAY be in transit and
1956 * unacknowledged at any one time. If a sender, after sending
1957 * an ASCONF chunk, decides it needs to transfer another
1958 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1959 * returns from the previous ASCONF Chunk before sending a
1960 * subsequent ASCONF. Note this restriction binds each side,
1961 * so at any time two ASCONF may be in-transit on any given
1962 * association (one sent from each endpoint).
1963 *
1964 * [This is our one-and-only-one ASCONF in flight. If we do
1965 * not have an ASCONF in flight, this is NULL.]
1966 */
1967 struct sctp_chunk *addip_last_asconf;
1968
1969 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
1970 *
1971 * This is needed to implement itmes E1 - E4 of the updated
1972 * spec. Here is the justification:
1973 *
1974 * Since the peer may bundle multiple ASCONF chunks toward us,
1975 * we now need the ability to cache multiple ACKs. The section
1976 * describes in detail how they are cached and cleaned up.
1977 */
1978 struct list_head asconf_ack_list;
1979
1980 /* These ASCONF chunks are waiting to be sent.
1981 *
1982 * These chunaks can't be pushed to outqueue until receiving
1983 * ASCONF_ACK for the previous ASCONF indicated by
1984 * addip_last_asconf, so as to guarantee that only one ASCONF
1985 * is in flight at any time.
1986 *
1987 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1988 *
1989 * In defining the ASCONF Chunk transfer procedures, it is
1990 * essential that these transfers MUST NOT cause congestion
1991 * within the network. To achieve this, we place these
1992 * restrictions on the transfer of ASCONF Chunks:
1993 *
1994 * R1) One and only one ASCONF Chunk MAY be in transit and
1995 * unacknowledged at any one time. If a sender, after sending
1996 * an ASCONF chunk, decides it needs to transfer another
1997 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1998 * returns from the previous ASCONF Chunk before sending a
1999 * subsequent ASCONF. Note this restriction binds each side,
2000 * so at any time two ASCONF may be in-transit on any given
2001 * association (one sent from each endpoint).
2002 *
2003 *
2004 * [I really think this is EXACTLY the sort of intelligence
2005 * which already resides in sctp_outq. Please move this
2006 * queue and its supporting logic down there. --piggy]
2007 */
2008 struct list_head addip_chunk_list;
2009
2010 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2011 *
2012 * A2) A serial number should be assigned to the Chunk. The
2013 * serial number SHOULD be a monotonically increasing
2014 * number. The serial number SHOULD be initialized at
2015 * the start of the association to the same value as the
2016 * Initial TSN and every time a new ASCONF chunk is created
2017 * it is incremented by one after assigning the serial number
2018 * to the newly created chunk.
2019 *
2020 * ADDIP
2021 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
2022 *
2023 * Serial Number : 32 bits (unsigned integer)
2024 *
2025 * This value represents a Serial Number for the ASCONF
2026 * Chunk. The valid range of Serial Number is from 0 to
2027 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
2028 * after reaching 4294967295.
2029 */
2030 __u32 addip_serial;
2031 int src_out_of_asoc_ok;
2032 union sctp_addr *asconf_addr_del_pending;
2033 struct sctp_transport *new_transport;
2034
2035 /* SCTP AUTH: list of the endpoint shared keys. These
2036 * keys are provided out of band by the user applicaton
2037 * and can't change during the lifetime of the association
2038 */
2039 struct list_head endpoint_shared_keys;
2040
2041 /* SCTP AUTH:
2042 * The current generated assocaition shared key (secret)
2043 */
2044 struct sctp_auth_bytes *asoc_shared_key;
2045 struct sctp_shared_key *shkey;
2046
2047 /* SCTP AUTH: hmac id of the first peer requested algorithm
2048 * that we support.
2049 */
2050 __u16 default_hmac_id;
2051
2052 __u16 active_key_id;
2053
2054 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */
2055 temp:1, /* Is it a temporary association? */
2056 force_delay:1;
2057
2058 __u8 strreset_enable;
2059 __u8 strreset_outstanding; /* request param count on the fly */
2060
2061 __u32 strreset_outseq; /* Update after receiving response */
2062 __u32 strreset_inseq; /* Update after receiving request */
2063 __u32 strreset_result[2]; /* save the results of last 2 responses */
2064
2065 struct sctp_chunk *strreset_chunk; /* save request chunk */
2066
2067 struct sctp_priv_assoc_stats stats;
2068
2069 int sent_cnt_removable;
2070
2071 __u16 subscribe;
2072
2073 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1];
2074 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1];
2075
2076 struct rcu_head rcu;
2077 };
2078
2079
2080 /* An eyecatcher for determining if we are really looking at an
2081 * association data structure.
2082 */
2083 enum {
2084 SCTP_ASSOC_EYECATCHER = 0xa550c123,
2085 };
2086
2087 /* Recover the outter association structure. */
sctp_assoc(struct sctp_ep_common * base)2088 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
2089 {
2090 struct sctp_association *asoc;
2091
2092 asoc = container_of(base, struct sctp_association, base);
2093 return asoc;
2094 }
2095
2096 /* These are function signatures for manipulating associations. */
2097
2098
2099 struct sctp_association *
2100 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk,
2101 enum sctp_scope scope, gfp_t gfp);
2102 void sctp_association_free(struct sctp_association *);
2103 void sctp_association_put(struct sctp_association *);
2104 void sctp_association_hold(struct sctp_association *);
2105
2106 struct sctp_transport *sctp_assoc_choose_alter_transport(
2107 struct sctp_association *, struct sctp_transport *);
2108 void sctp_assoc_update_retran_path(struct sctp_association *);
2109 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
2110 const union sctp_addr *);
2111 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
2112 const union sctp_addr *laddr);
2113 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
2114 const union sctp_addr *address,
2115 const gfp_t gfp,
2116 const int peer_state);
2117 void sctp_assoc_del_peer(struct sctp_association *asoc,
2118 const union sctp_addr *addr);
2119 void sctp_assoc_rm_peer(struct sctp_association *asoc,
2120 struct sctp_transport *peer);
2121 void sctp_assoc_control_transport(struct sctp_association *asoc,
2122 struct sctp_transport *transport,
2123 enum sctp_transport_cmd command,
2124 sctp_sn_error_t error);
2125 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
2126 void sctp_assoc_migrate(struct sctp_association *, struct sock *);
2127 int sctp_assoc_update(struct sctp_association *old,
2128 struct sctp_association *new);
2129
2130 __u32 sctp_association_get_next_tsn(struct sctp_association *);
2131
2132 void sctp_assoc_update_frag_point(struct sctp_association *asoc);
2133 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu);
2134 void sctp_assoc_sync_pmtu(struct sctp_association *asoc);
2135 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int);
2136 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int);
2137 void sctp_assoc_set_primary(struct sctp_association *,
2138 struct sctp_transport *);
2139 void sctp_assoc_del_nonprimary_peers(struct sctp_association *,
2140 struct sctp_transport *);
2141 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc,
2142 enum sctp_scope scope, gfp_t gfp);
2143 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
2144 struct sctp_cookie*,
2145 gfp_t gfp);
2146 int sctp_assoc_set_id(struct sctp_association *, gfp_t);
2147 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc);
2148 struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
2149 const struct sctp_association *asoc,
2150 __be32 serial);
2151 void sctp_asconf_queue_teardown(struct sctp_association *asoc);
2152
2153 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
2154 const union sctp_addr *ss2);
2155 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
2156
2157 /* A convenience structure to parse out SCTP specific CMSGs. */
2158 struct sctp_cmsgs {
2159 struct sctp_initmsg *init;
2160 struct sctp_sndrcvinfo *srinfo;
2161 struct sctp_sndinfo *sinfo;
2162 struct sctp_prinfo *prinfo;
2163 struct sctp_authinfo *authinfo;
2164 struct msghdr *addrs_msg;
2165 };
2166
2167 /* Structure for tracking memory objects */
2168 struct sctp_dbg_objcnt_entry {
2169 char *label;
2170 atomic_t *counter;
2171 };
2172
2173 #endif /* __sctp_structs_h__ */
2174
