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
228 /* Fields after this point will be skipped on copies, like on accept
229 * and peeloff operations
230 */
231
232 /* Receive to here while partial delivery is in effect. */
233 struct sk_buff_head pd_lobby;
234
235 struct list_head auto_asconf_list;
236 int do_auto_asconf;
237 };
238
sctp_sk(const struct sock * sk)239 static inline struct sctp_sock *sctp_sk(const struct sock *sk)
240 {
241 return (struct sctp_sock *)sk;
242 }
243
sctp_opt2sk(const struct sctp_sock * sp)244 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
245 {
246 return (struct sock *)sp;
247 }
248
249 #if IS_ENABLED(CONFIG_IPV6)
250 struct sctp6_sock {
251 struct sctp_sock sctp;
252 struct ipv6_pinfo inet6;
253 };
254 #endif /* CONFIG_IPV6 */
255
256
257 /* This is our APPLICATION-SPECIFIC state cookie.
258 * THIS IS NOT DICTATED BY THE SPECIFICATION.
259 */
260 /* These are the parts of an association which we send in the cookie.
261 * Most of these are straight out of:
262 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
263 *
264 */
265
266 struct sctp_cookie {
267
268 /* My : Tag expected in every inbound packet and sent
269 * Verification: in the INIT or INIT ACK chunk.
270 * Tag :
271 */
272 __u32 my_vtag;
273
274 /* Peer's : Tag expected in every outbound packet except
275 * Verification: in the INIT chunk.
276 * Tag :
277 */
278 __u32 peer_vtag;
279
280 /* The rest of these are not from the spec, but really need to
281 * be in the cookie.
282 */
283
284 /* My Tie Tag : Assist in discovering a restarting association. */
285 __u32 my_ttag;
286
287 /* Peer's Tie Tag: Assist in discovering a restarting association. */
288 __u32 peer_ttag;
289
290 /* When does this cookie expire? */
291 ktime_t expiration;
292
293 /* Number of inbound/outbound streams which are set
294 * and negotiated during the INIT process.
295 */
296 __u16 sinit_num_ostreams;
297 __u16 sinit_max_instreams;
298
299 /* This is the first sequence number I used. */
300 __u32 initial_tsn;
301
302 /* This holds the originating address of the INIT packet. */
303 union sctp_addr peer_addr;
304
305 /* IG Section 2.35.3
306 * Include the source port of the INIT-ACK
307 */
308 __u16 my_port;
309
310 __u8 prsctp_capable;
311
312 /* Padding for future use */
313 __u8 padding;
314
315 __u32 adaptation_ind;
316
317 __u8 auth_random[sizeof(struct sctp_paramhdr) +
318 SCTP_AUTH_RANDOM_LENGTH];
319 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2];
320 __u8 auth_chunks[sizeof(struct sctp_paramhdr) + SCTP_AUTH_MAX_CHUNKS];
321
322 /* This is a shim for my peer's INIT packet, followed by
323 * a copy of the raw address list of the association.
324 * The length of the raw address list is saved in the
325 * raw_addr_list_len field, which will be used at the time when
326 * the association TCB is re-constructed from the cookie.
327 */
328 __u32 raw_addr_list_len;
329 struct sctp_init_chunk peer_init[0];
330 };
331
332
333 /* The format of our cookie that we send to our peer. */
334 struct sctp_signed_cookie {
335 __u8 signature[SCTP_SECRET_SIZE];
336 __u32 __pad; /* force sctp_cookie alignment to 64 bits */
337 struct sctp_cookie c;
338 } __packed;
339
340 /* This is another convenience type to allocate memory for address
341 * params for the maximum size and pass such structures around
342 * internally.
343 */
344 union sctp_addr_param {
345 struct sctp_paramhdr p;
346 struct sctp_ipv4addr_param v4;
347 struct sctp_ipv6addr_param v6;
348 };
349
350 /* A convenience type to allow walking through the various
351 * parameters and avoid casting all over the place.
352 */
353 union sctp_params {
354 void *v;
355 struct sctp_paramhdr *p;
356 struct sctp_cookie_preserve_param *life;
357 struct sctp_hostname_param *dns;
358 struct sctp_cookie_param *cookie;
359 struct sctp_supported_addrs_param *sat;
360 struct sctp_ipv4addr_param *v4;
361 struct sctp_ipv6addr_param *v6;
362 union sctp_addr_param *addr;
363 struct sctp_adaptation_ind_param *aind;
364 struct sctp_supported_ext_param *ext;
365 struct sctp_random_param *random;
366 struct sctp_chunks_param *chunks;
367 struct sctp_hmac_algo_param *hmac_algo;
368 struct sctp_addip_param *addip;
369 };
370
371 /* RFC 2960. Section 3.3.5 Heartbeat.
372 * Heartbeat Information: variable length
373 * The Sender-specific Heartbeat Info field should normally include
374 * information about the sender's current time when this HEARTBEAT
375 * chunk is sent and the destination transport address to which this
376 * HEARTBEAT is sent (see Section 8.3).
377 */
378 struct sctp_sender_hb_info {
379 struct sctp_paramhdr param_hdr;
380 union sctp_addr daddr;
381 unsigned long sent_at;
382 __u64 hb_nonce;
383 };
384
385 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt,
386 gfp_t gfp);
387 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid);
388 void sctp_stream_free(struct sctp_stream *stream);
389 void sctp_stream_clear(struct sctp_stream *stream);
390 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new);
391
392 /* What is the current SSN number for this stream? */
393 #define sctp_ssn_peek(stream, type, sid) \
394 (sctp_stream_##type((stream), (sid))->ssn)
395
396 /* Return the next SSN number for this stream. */
397 #define sctp_ssn_next(stream, type, sid) \
398 (sctp_stream_##type((stream), (sid))->ssn++)
399
400 /* Skip over this ssn and all below. */
401 #define sctp_ssn_skip(stream, type, sid, ssn) \
402 (sctp_stream_##type((stream), (sid))->ssn = ssn + 1)
403
404 /* What is the current MID number for this stream? */
405 #define sctp_mid_peek(stream, type, sid) \
406 (sctp_stream_##type((stream), (sid))->mid)
407
408 /* Return the next MID number for this stream. */
409 #define sctp_mid_next(stream, type, sid) \
410 (sctp_stream_##type((stream), (sid))->mid++)
411
412 /* Skip over this mid and all below. */
413 #define sctp_mid_skip(stream, type, sid, mid) \
414 (sctp_stream_##type((stream), (sid))->mid = mid + 1)
415
416 /* What is the current MID_uo number for this stream? */
417 #define sctp_mid_uo_peek(stream, type, sid) \
418 (sctp_stream_##type((stream), (sid))->mid_uo)
419
420 /* Return the next MID_uo number for this stream. */
421 #define sctp_mid_uo_next(stream, type, sid) \
422 (sctp_stream_##type((stream), (sid))->mid_uo++)
423
424 /*
425 * Pointers to address related SCTP functions.
426 * (i.e. things that depend on the address family.)
427 */
428 struct sctp_af {
429 int (*sctp_xmit) (struct sk_buff *skb,
430 struct sctp_transport *);
431 int (*setsockopt) (struct sock *sk,
432 int level,
433 int optname,
434 char __user *optval,
435 unsigned int optlen);
436 int (*getsockopt) (struct sock *sk,
437 int level,
438 int optname,
439 char __user *optval,
440 int __user *optlen);
441 int (*compat_setsockopt) (struct sock *sk,
442 int level,
443 int optname,
444 char __user *optval,
445 unsigned int optlen);
446 int (*compat_getsockopt) (struct sock *sk,
447 int level,
448 int optname,
449 char __user *optval,
450 int __user *optlen);
451 void (*get_dst) (struct sctp_transport *t,
452 union sctp_addr *saddr,
453 struct flowi *fl,
454 struct sock *sk);
455 void (*get_saddr) (struct sctp_sock *sk,
456 struct sctp_transport *t,
457 struct flowi *fl);
458 void (*copy_addrlist) (struct list_head *,
459 struct net_device *);
460 int (*cmp_addr) (const union sctp_addr *addr1,
461 const union sctp_addr *addr2);
462 void (*addr_copy) (union sctp_addr *dst,
463 union sctp_addr *src);
464 void (*from_skb) (union sctp_addr *,
465 struct sk_buff *skb,
466 int saddr);
467 void (*from_sk) (union sctp_addr *,
468 struct sock *sk);
469 bool (*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 enum sctp_scope (*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 int (*ip_options_len)(struct sock *sk);
490 sa_family_t sa_family;
491 struct list_head list;
492 };
493
494 struct sctp_af *sctp_get_af_specific(sa_family_t);
495 int sctp_register_af(struct sctp_af *);
496
497 /* Protocol family functions. */
498 struct sctp_pf {
499 void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
500 void (*skb_msgname) (struct sk_buff *, char *, int *);
501 int (*af_supported) (sa_family_t, struct sctp_sock *);
502 int (*cmp_addr) (const union sctp_addr *,
503 const union sctp_addr *,
504 struct sctp_sock *);
505 int (*bind_verify) (struct sctp_sock *, union sctp_addr *);
506 int (*send_verify) (struct sctp_sock *, union sctp_addr *);
507 int (*supported_addrs)(const struct sctp_sock *, __be16 *);
508 struct sock *(*create_accept_sk) (struct sock *sk,
509 struct sctp_association *asoc,
510 bool kern);
511 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr);
512 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk);
513 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk);
514 void (*copy_ip_options)(struct sock *sk, struct sock *newsk);
515 struct sctp_af *af;
516 };
517
518
519 /* Structure to track chunk fragments that have been acked, but peer
520 * fragments of the same message have not.
521 */
522 struct sctp_datamsg {
523 /* Chunks waiting to be submitted to lower layer. */
524 struct list_head chunks;
525 /* Reference counting. */
526 refcount_t refcnt;
527 /* When is this message no longer interesting to the peer? */
528 unsigned long expires_at;
529 /* Did the messenge fail to send? */
530 int send_error;
531 u8 send_failed:1,
532 can_delay:1, /* should this message be Nagle delayed */
533 abandoned:1; /* should this message be abandoned */
534 };
535
536 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
537 struct sctp_sndrcvinfo *,
538 struct iov_iter *);
539 void sctp_datamsg_free(struct sctp_datamsg *);
540 void sctp_datamsg_put(struct sctp_datamsg *);
541 void sctp_chunk_fail(struct sctp_chunk *, int error);
542 int sctp_chunk_abandoned(struct sctp_chunk *);
543
544 /* RFC2960 1.4 Key Terms
545 *
546 * o Chunk: A unit of information within an SCTP packet, consisting of
547 * a chunk header and chunk-specific content.
548 *
549 * As a matter of convenience, we remember the SCTP common header for
550 * each chunk as well as a few other header pointers...
551 */
552 struct sctp_chunk {
553 struct list_head list;
554
555 refcount_t refcnt;
556
557 /* How many times this chunk have been sent, for prsctp RTX policy */
558 int sent_count;
559
560 union {
561 /* This is our link to the per-transport transmitted list. */
562 struct list_head transmitted_list;
563 /* List in specific stream outq */
564 struct list_head stream_list;
565 };
566
567 /* This field is used by chunks that hold fragmented data.
568 * For the first fragment this is the list that holds the rest of
569 * fragments. For the remaining fragments, this is the link to the
570 * frag_list maintained in the first fragment.
571 */
572 struct list_head frag_list;
573
574 /* This points to the sk_buff containing the actual data. */
575 struct sk_buff *skb;
576
577 union {
578 /* In case of GSO packets, this will store the head one */
579 struct sk_buff *head_skb;
580 /* In case of auth enabled, this will point to the shkey */
581 struct sctp_shared_key *shkey;
582 };
583
584 /* These are the SCTP headers by reverse order in a packet.
585 * Note that some of these may happen more than once. In that
586 * case, we point at the "current" one, whatever that means
587 * for that level of header.
588 */
589
590 /* We point this at the FIRST TLV parameter to chunk_hdr. */
591 union sctp_params param_hdr;
592 union {
593 __u8 *v;
594 struct sctp_datahdr *data_hdr;
595 struct sctp_inithdr *init_hdr;
596 struct sctp_sackhdr *sack_hdr;
597 struct sctp_heartbeathdr *hb_hdr;
598 struct sctp_sender_hb_info *hbs_hdr;
599 struct sctp_shutdownhdr *shutdown_hdr;
600 struct sctp_signed_cookie *cookie_hdr;
601 struct sctp_ecnehdr *ecne_hdr;
602 struct sctp_cwrhdr *ecn_cwr_hdr;
603 struct sctp_errhdr *err_hdr;
604 struct sctp_addiphdr *addip_hdr;
605 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
606 struct sctp_authhdr *auth_hdr;
607 struct sctp_idatahdr *idata_hdr;
608 struct sctp_ifwdtsn_hdr *ifwdtsn_hdr;
609 } subh;
610
611 __u8 *chunk_end;
612
613 struct sctp_chunkhdr *chunk_hdr;
614 struct sctphdr *sctp_hdr;
615
616 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
617 struct sctp_sndrcvinfo sinfo;
618
619 /* Which association does this belong to? */
620 struct sctp_association *asoc;
621
622 /* What endpoint received this chunk? */
623 struct sctp_ep_common *rcvr;
624
625 /* We fill this in if we are calculating RTT. */
626 unsigned long sent_at;
627
628 /* What is the origin IP address for this chunk? */
629 union sctp_addr source;
630 /* Destination address for this chunk. */
631 union sctp_addr dest;
632
633 /* For outbound message, track all fragments for SEND_FAILED. */
634 struct sctp_datamsg *msg;
635
636 /* For an inbound chunk, this tells us where it came from.
637 * For an outbound chunk, it tells us where we'd like it to
638 * go. It is NULL if we have no preference.
639 */
640 struct sctp_transport *transport;
641
642 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO
643 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
644 * spec violates the principle premis that all chunks are processed
645 * in order.
646 */
647 struct sk_buff *auth_chunk;
648
649 #define SCTP_CAN_FRTX 0x0
650 #define SCTP_NEED_FRTX 0x1
651 #define SCTP_DONT_FRTX 0x2
652 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */
653 has_tsn:1, /* Does this chunk have a TSN yet? */
654 has_ssn:1, /* Does this chunk have a SSN yet? */
655 #define has_mid has_ssn
656 singleton:1, /* Only chunk in the packet? */
657 end_of_packet:1, /* Last chunk in the packet? */
658 ecn_ce_done:1, /* Have we processed the ECN CE bit? */
659 pdiscard:1, /* Discard the whole packet now? */
660 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */
661 data_accepted:1, /* At least 1 chunk accepted */
662 auth:1, /* IN: was auth'ed | OUT: needs auth */
663 has_asconf:1, /* IN: have seen an asconf before */
664 tsn_missing_report:2, /* Data chunk missing counter. */
665 fast_retransmit:2; /* Is this chunk fast retransmitted? */
666 };
667
668 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1)
669 void sctp_chunk_hold(struct sctp_chunk *);
670 void sctp_chunk_put(struct sctp_chunk *);
671 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len,
672 struct iov_iter *from);
673 void sctp_chunk_free(struct sctp_chunk *);
674 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
675 struct sctp_chunk *sctp_chunkify(struct sk_buff *,
676 const struct sctp_association *,
677 struct sock *, gfp_t gfp);
678 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
679 union sctp_addr *);
680 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
681
sctp_chunk_stream_no(struct sctp_chunk * ch)682 static inline __u16 sctp_chunk_stream_no(struct sctp_chunk *ch)
683 {
684 return ntohs(ch->subh.data_hdr->stream);
685 }
686
687 enum {
688 SCTP_ADDR_NEW, /* new address added to assoc/ep */
689 SCTP_ADDR_SRC, /* address can be used as source */
690 SCTP_ADDR_DEL, /* address about to be deleted */
691 };
692
693 /* This is a structure for holding either an IPv6 or an IPv4 address. */
694 struct sctp_sockaddr_entry {
695 struct list_head list;
696 struct rcu_head rcu;
697 union sctp_addr a;
698 __u8 state;
699 __u8 valid;
700 };
701
702 #define SCTP_ADDRESS_TICK_DELAY 500
703
704 /* This structure holds lists of chunks as we are assembling for
705 * transmission.
706 */
707 struct sctp_packet {
708 /* These are the SCTP header values (host order) for the packet. */
709 __u16 source_port;
710 __u16 destination_port;
711 __u32 vtag;
712
713 /* This contains the payload chunks. */
714 struct list_head chunk_list;
715
716 /* This is the overhead of the sctp and ip headers. */
717 size_t overhead;
718 /* This is the total size of all chunks INCLUDING padding. */
719 size_t size;
720 /* This is the maximum size this packet may have */
721 size_t max_size;
722
723 /* The packet is destined for this transport address.
724 * The function we finally use to pass down to the next lower
725 * layer lives in the transport structure.
726 */
727 struct sctp_transport *transport;
728
729 /* pointer to the auth chunk for this packet */
730 struct sctp_chunk *auth;
731
732 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */
733 has_sack:1, /* This packet contains a SACK chunk. */
734 has_auth:1, /* This packet contains an AUTH chunk */
735 has_data:1, /* This packet contains at least 1 DATA chunk */
736 ipfragok:1; /* So let ip fragment this packet */
737 };
738
739 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *,
740 __u16 sport, __u16 dport);
741 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
742 enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet,
743 struct sctp_chunk *chunk,
744 int one_packet, gfp_t gfp);
745 enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet,
746 struct sctp_chunk *chunk);
747 int sctp_packet_transmit(struct sctp_packet *, gfp_t);
748 void sctp_packet_free(struct sctp_packet *);
749
sctp_packet_empty(struct sctp_packet * packet)750 static inline int sctp_packet_empty(struct sctp_packet *packet)
751 {
752 return packet->size == packet->overhead;
753 }
754
755 /* This represents a remote transport address.
756 * For local transport addresses, we just use union sctp_addr.
757 *
758 * RFC2960 Section 1.4 Key Terms
759 *
760 * o Transport address: A Transport Address is traditionally defined
761 * by Network Layer address, Transport Layer protocol and Transport
762 * Layer port number. In the case of SCTP running over IP, a
763 * transport address is defined by the combination of an IP address
764 * and an SCTP port number (where SCTP is the Transport protocol).
765 *
766 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
767 *
768 * o The sender keeps a separate congestion control parameter set for
769 * each of the destination addresses it can send to (not each
770 * source-destination pair but for each destination). The parameters
771 * should decay if the address is not used for a long enough time
772 * period.
773 *
774 */
775 struct sctp_transport {
776 /* A list of transports. */
777 struct list_head transports;
778 struct rhlist_head node;
779
780 /* Reference counting. */
781 refcount_t refcnt;
782 /* RTO-Pending : A flag used to track if one of the DATA
783 * chunks sent to this address is currently being
784 * used to compute a RTT. If this flag is 0,
785 * the next DATA chunk sent to this destination
786 * should be used to compute a RTT and this flag
787 * should be set. Every time the RTT
788 * calculation completes (i.e. the DATA chunk
789 * is SACK'd) clear this flag.
790 */
791 __u32 rto_pending:1,
792
793 /*
794 * hb_sent : a flag that signals that we have a pending
795 * heartbeat.
796 */
797 hb_sent:1,
798
799 /* Is the Path MTU update pending on this tranport */
800 pmtu_pending:1,
801
802 dst_pending_confirm:1, /* need to confirm neighbour */
803
804 /* Has this transport moved the ctsn since we last sacked */
805 sack_generation:1;
806 u32 dst_cookie;
807
808 struct flowi fl;
809
810 /* This is the peer's IP address and port. */
811 union sctp_addr ipaddr;
812
813 /* These are the functions we call to handle LLP stuff. */
814 struct sctp_af *af_specific;
815
816 /* Which association do we belong to? */
817 struct sctp_association *asoc;
818
819 /* RFC2960
820 *
821 * 12.3 Per Transport Address Data
822 *
823 * For each destination transport address in the peer's
824 * address list derived from the INIT or INIT ACK chunk, a
825 * number of data elements needs to be maintained including:
826 */
827 /* RTO : The current retransmission timeout value. */
828 unsigned long rto;
829
830 __u32 rtt; /* This is the most recent RTT. */
831
832 /* RTTVAR : The current RTT variation. */
833 __u32 rttvar;
834
835 /* SRTT : The current smoothed round trip time. */
836 __u32 srtt;
837
838 /*
839 * These are the congestion stats.
840 */
841 /* cwnd : The current congestion window. */
842 __u32 cwnd; /* This is the actual cwnd. */
843
844 /* ssthresh : The current slow start threshold value. */
845 __u32 ssthresh;
846
847 /* partial : The tracking method for increase of cwnd when in
848 * bytes acked : congestion avoidance mode (see Section 6.2.2)
849 */
850 __u32 partial_bytes_acked;
851
852 /* Data that has been sent, but not acknowledged. */
853 __u32 flight_size;
854
855 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */
856
857 /* Destination */
858 struct dst_entry *dst;
859 /* Source address. */
860 union sctp_addr saddr;
861
862 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
863 * the destination address every heartbeat interval.
864 */
865 unsigned long hbinterval;
866
867 /* SACK delay timeout */
868 unsigned long sackdelay;
869 __u32 sackfreq;
870
871 atomic_t mtu_info;
872
873 /* When was the last time that we heard from this transport? We use
874 * this to pick new active and retran paths.
875 */
876 ktime_t last_time_heard;
877
878 /* When was the last time that we sent a chunk using this
879 * transport? We use this to check for idle transports
880 */
881 unsigned long last_time_sent;
882
883 /* Last time(in jiffies) when cwnd is reduced due to the congestion
884 * indication based on ECNE chunk.
885 */
886 unsigned long last_time_ecne_reduced;
887
888 /* This is the max_retrans value for the transport and will
889 * be initialized from the assocs value. This can be changed
890 * using the SCTP_SET_PEER_ADDR_PARAMS socket option.
891 */
892 __u16 pathmaxrxt;
893
894 __u32 flowlabel;
895 __u8 dscp;
896
897 /* This is the partially failed retrans value for the transport
898 * and will be initialized from the assocs value. This can be changed
899 * using the SCTP_PEER_ADDR_THLDS socket option
900 */
901 int pf_retrans;
902 /* PMTU : The current known path MTU. */
903 __u32 pathmtu;
904
905 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
906 __u32 param_flags;
907
908 /* The number of times INIT has been sent on this transport. */
909 int init_sent_count;
910
911 /* state : The current state of this destination,
912 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
913 */
914 int state;
915
916 /* These are the error stats for this destination. */
917
918 /* Error count : The current error count for this destination. */
919 unsigned short error_count;
920
921 /* Per : A timer used by each destination.
922 * Destination :
923 * Timer :
924 *
925 * [Everywhere else in the text this is called T3-rtx. -ed]
926 */
927 struct timer_list T3_rtx_timer;
928
929 /* Heartbeat timer is per destination. */
930 struct timer_list hb_timer;
931
932 /* Timer to handle ICMP proto unreachable envets */
933 struct timer_list proto_unreach_timer;
934
935 /* Timer to handler reconf chunk rtx */
936 struct timer_list reconf_timer;
937
938 /* Since we're using per-destination retransmission timers
939 * (see above), we're also using per-destination "transmitted"
940 * queues. This probably ought to be a private struct
941 * accessible only within the outqueue, but it's not, yet.
942 */
943 struct list_head transmitted;
944
945 /* We build bundle-able packets for this transport here. */
946 struct sctp_packet packet;
947
948 /* This is the list of transports that have chunks to send. */
949 struct list_head send_ready;
950
951 /* State information saved for SFR_CACC algorithm. The key
952 * idea in SFR_CACC is to maintain state at the sender on a
953 * per-destination basis when a changeover happens.
954 * char changeover_active;
955 * char cycling_changeover;
956 * __u32 next_tsn_at_change;
957 * char cacc_saw_newack;
958 */
959 struct {
960 /* An unsigned integer, which stores the next TSN to be
961 * used by the sender, at the moment of changeover.
962 */
963 __u32 next_tsn_at_change;
964
965 /* A flag which indicates the occurrence of a changeover */
966 char changeover_active;
967
968 /* A flag which indicates whether the change of primary is
969 * the first switch to this destination address during an
970 * active switch.
971 */
972 char cycling_changeover;
973
974 /* A temporary flag, which is used during the processing of
975 * a SACK to estimate the causative TSN(s)'s group.
976 */
977 char cacc_saw_newack;
978 } cacc;
979
980 /* 64-bit random number sent with heartbeat. */
981 __u64 hb_nonce;
982
983 struct rcu_head rcu;
984 };
985
986 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *,
987 gfp_t);
988 void sctp_transport_set_owner(struct sctp_transport *,
989 struct sctp_association *);
990 void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
991 struct sctp_sock *);
992 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk);
993 void sctp_transport_free(struct sctp_transport *);
994 void sctp_transport_reset_t3_rtx(struct sctp_transport *);
995 void sctp_transport_reset_hb_timer(struct sctp_transport *);
996 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport);
997 int sctp_transport_hold(struct sctp_transport *);
998 void sctp_transport_put(struct sctp_transport *);
999 void sctp_transport_update_rto(struct sctp_transport *, __u32);
1000 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
1001 void sctp_transport_lower_cwnd(struct sctp_transport *t,
1002 enum sctp_lower_cwnd reason);
1003 void sctp_transport_burst_limited(struct sctp_transport *);
1004 void sctp_transport_burst_reset(struct sctp_transport *);
1005 unsigned long sctp_transport_timeout(struct sctp_transport *);
1006 void sctp_transport_reset(struct sctp_transport *t);
1007 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu);
1008 void sctp_transport_immediate_rtx(struct sctp_transport *);
1009 void sctp_transport_dst_release(struct sctp_transport *t);
1010 void sctp_transport_dst_confirm(struct sctp_transport *t);
1011
1012
1013 /* This is the structure we use to queue packets as they come into
1014 * SCTP. We write packets to it and read chunks from it.
1015 */
1016 struct sctp_inq {
1017 /* This is actually a queue of sctp_chunk each
1018 * containing a partially decoded packet.
1019 */
1020 struct list_head in_chunk_list;
1021 /* This is the packet which is currently off the in queue and is
1022 * being worked on through the inbound chunk processing.
1023 */
1024 struct sctp_chunk *in_progress;
1025
1026 /* This is the delayed task to finish delivering inbound
1027 * messages.
1028 */
1029 struct work_struct immediate;
1030 };
1031
1032 void sctp_inq_init(struct sctp_inq *);
1033 void sctp_inq_free(struct sctp_inq *);
1034 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
1035 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
1036 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *);
1037 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t);
1038
1039 /* This is the structure we use to hold outbound chunks. You push
1040 * chunks in and they automatically pop out the other end as bundled
1041 * packets (it calls (*output_handler)()).
1042 *
1043 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1044 * and 8.2 of the v13 draft.
1045 *
1046 * It handles retransmissions. The connection to the timeout portion
1047 * of the state machine is through sctp_..._timeout() and timeout_handler.
1048 *
1049 * If you feed it SACKs, it will eat them.
1050 *
1051 * If you give it big chunks, it will fragment them.
1052 *
1053 * It assigns TSN's to data chunks. This happens at the last possible
1054 * instant before transmission.
1055 *
1056 * When free()'d, it empties itself out via output_handler().
1057 */
1058 struct sctp_outq {
1059 struct sctp_association *asoc;
1060
1061 /* Data pending that has never been transmitted. */
1062 struct list_head out_chunk_list;
1063
1064 /* Stream scheduler being used */
1065 struct sctp_sched_ops *sched;
1066
1067 unsigned int out_qlen; /* Total length of queued data chunks. */
1068
1069 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1070 unsigned int error;
1071
1072 /* These are control chunks we want to send. */
1073 struct list_head control_chunk_list;
1074
1075 /* These are chunks that have been sacked but are above the
1076 * CTSN, or cumulative tsn ack point.
1077 */
1078 struct list_head sacked;
1079
1080 /* Put chunks on this list to schedule them for
1081 * retransmission.
1082 */
1083 struct list_head retransmit;
1084
1085 /* Put chunks on this list to save them for FWD TSN processing as
1086 * they were abandoned.
1087 */
1088 struct list_head abandoned;
1089
1090 /* How many unackd bytes do we have in-flight? */
1091 __u32 outstanding_bytes;
1092
1093 /* Are we doing fast-rtx on this queue */
1094 char fast_rtx;
1095
1096 /* Corked? */
1097 char cork;
1098 };
1099
1100 void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1101 void sctp_outq_teardown(struct sctp_outq *);
1102 void sctp_outq_free(struct sctp_outq*);
1103 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t);
1104 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *);
1105 int sctp_outq_is_empty(const struct sctp_outq *);
1106 void sctp_outq_restart(struct sctp_outq *);
1107
1108 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport,
1109 enum sctp_retransmit_reason reason);
1110 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1111 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp);
1112 void sctp_prsctp_prune(struct sctp_association *asoc,
1113 struct sctp_sndrcvinfo *sinfo, int msg_len);
1114 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn);
1115 /* Uncork and flush an outqueue. */
sctp_outq_cork(struct sctp_outq * q)1116 static inline void sctp_outq_cork(struct sctp_outq *q)
1117 {
1118 q->cork = 1;
1119 }
1120
1121 /* SCTP skb control block.
1122 * sctp_input_cb is currently used on rx and sock rx queue
1123 */
1124 struct sctp_input_cb {
1125 union {
1126 struct inet_skb_parm h4;
1127 #if IS_ENABLED(CONFIG_IPV6)
1128 struct inet6_skb_parm h6;
1129 #endif
1130 } header;
1131 struct sctp_chunk *chunk;
1132 struct sctp_af *af;
1133 };
1134 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0]))
1135
1136 struct sctp_output_cb {
1137 struct sk_buff *last;
1138 };
1139 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0]))
1140
sctp_gso_headskb(const struct sk_buff * skb)1141 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb)
1142 {
1143 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk;
1144
1145 return chunk->head_skb ? : skb;
1146 }
1147
1148 /* These bind address data fields common between endpoints and associations */
1149 struct sctp_bind_addr {
1150
1151 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1152 *
1153 * SCTP Port: The local SCTP port number the endpoint is
1154 * bound to.
1155 */
1156 __u16 port;
1157
1158 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1159 *
1160 * Address List: The list of IP addresses that this instance
1161 * has bound. This information is passed to one's
1162 * peer(s) in INIT and INIT ACK chunks.
1163 */
1164 struct list_head address_list;
1165 };
1166
1167 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1168 void sctp_bind_addr_free(struct sctp_bind_addr *);
1169 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest,
1170 const struct sctp_bind_addr *src,
1171 enum sctp_scope scope, gfp_t gfp,
1172 int flags);
1173 int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
1174 const struct sctp_bind_addr *src,
1175 gfp_t gfp);
1176 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1177 int new_size, __u8 addr_state, gfp_t gfp);
1178 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1179 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1180 struct sctp_sock *);
1181 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *,
1182 struct sctp_sock *, struct sctp_sock *);
1183 int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
1184 const union sctp_addr *addr);
1185 int sctp_bind_addrs_check(struct sctp_sock *sp,
1186 struct sctp_sock *sp2, int cnt2);
1187 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp,
1188 const union sctp_addr *addrs,
1189 int addrcnt,
1190 struct sctp_sock *opt);
1191 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1192 int *addrs_len,
1193 gfp_t gfp);
1194 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1195 __u16 port, gfp_t gfp);
1196
1197 enum sctp_scope sctp_scope(const union sctp_addr *addr);
1198 int sctp_in_scope(struct net *net, const union sctp_addr *addr,
1199 const enum sctp_scope scope);
1200 int sctp_is_any(struct sock *sk, const union sctp_addr *addr);
1201 int sctp_is_ep_boundall(struct sock *sk);
1202
1203
1204 /* What type of endpoint? */
1205 enum sctp_endpoint_type {
1206 SCTP_EP_TYPE_SOCKET,
1207 SCTP_EP_TYPE_ASSOCIATION,
1208 };
1209
1210 /*
1211 * A common base class to bridge the implmentation view of a
1212 * socket (usually listening) endpoint versus an association's
1213 * local endpoint.
1214 * This common structure is useful for several purposes:
1215 * 1) Common interface for lookup routines.
1216 * a) Subfunctions work for either endpoint or association
1217 * b) Single interface to lookup allows hiding the lookup lock rather
1218 * than acquiring it externally.
1219 * 2) Common interface for the inbound chunk handling/state machine.
1220 * 3) Common object handling routines for reference counting, etc.
1221 * 4) Disentangle association lookup from endpoint lookup, where we
1222 * do not have to find our endpoint to find our association.
1223 *
1224 */
1225
1226 struct sctp_ep_common {
1227 /* Fields to help us manage our entries in the hash tables. */
1228 struct hlist_node node;
1229 int hashent;
1230
1231 /* Runtime type information. What kind of endpoint is this? */
1232 enum sctp_endpoint_type type;
1233
1234 /* Some fields to help us manage this object.
1235 * refcnt - Reference count access to this object.
1236 * dead - Do not attempt to use this object.
1237 */
1238 refcount_t refcnt;
1239 bool dead;
1240
1241 /* What socket does this endpoint belong to? */
1242 struct sock *sk;
1243
1244 /* Cache netns and it won't change once set */
1245 struct net *net;
1246
1247 /* This is where we receive inbound chunks. */
1248 struct sctp_inq inqueue;
1249
1250 /* This substructure includes the defining parameters of the
1251 * endpoint:
1252 * bind_addr.port is our shared port number.
1253 * bind_addr.address_list is our set of local IP addresses.
1254 */
1255 struct sctp_bind_addr bind_addr;
1256 };
1257
1258
1259 /* RFC Section 1.4 Key Terms
1260 *
1261 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1262 * multi-homed host, an SCTP endpoint is represented to its peers as a
1263 * combination of a set of eligible destination transport addresses to
1264 * which SCTP packets can be sent and a set of eligible source
1265 * transport addresses from which SCTP packets can be received.
1266 * All transport addresses used by an SCTP endpoint must use the
1267 * same port number, but can use multiple IP addresses. A transport
1268 * address used by an SCTP endpoint must not be used by another
1269 * SCTP endpoint. In other words, a transport address is unique
1270 * to an SCTP endpoint.
1271 *
1272 * From an implementation perspective, each socket has one of these.
1273 * A TCP-style socket will have exactly one association on one of
1274 * these. An UDP-style socket will have multiple associations hanging
1275 * off one of these.
1276 */
1277
1278 struct sctp_endpoint {
1279 /* Common substructure for endpoint and association. */
1280 struct sctp_ep_common base;
1281
1282 /* Associations: A list of current associations and mappings
1283 * to the data consumers for each association. This
1284 * may be in the form of a hash table or other
1285 * implementation dependent structure. The data
1286 * consumers may be process identification
1287 * information such as file descriptors, named pipe
1288 * pointer, or table pointers dependent on how SCTP
1289 * is implemented.
1290 */
1291 /* This is really a list of struct sctp_association entries. */
1292 struct list_head asocs;
1293
1294 /* Secret Key: A secret key used by this endpoint to compute
1295 * the MAC. This SHOULD be a cryptographic quality
1296 * random number with a sufficient length.
1297 * Discussion in [RFC1750] can be helpful in
1298 * selection of the key.
1299 */
1300 __u8 secret_key[SCTP_SECRET_SIZE];
1301
1302 /* digest: This is a digest of the sctp cookie. This field is
1303 * only used on the receive path when we try to validate
1304 * that the cookie has not been tampered with. We put
1305 * this here so we pre-allocate this once and can re-use
1306 * on every receive.
1307 */
1308 __u8 *digest;
1309
1310 /* sendbuf acct. policy. */
1311 __u32 sndbuf_policy;
1312
1313 /* rcvbuf acct. policy. */
1314 __u32 rcvbuf_policy;
1315
1316 /* SCTP AUTH: array of the HMACs that will be allocated
1317 * we need this per association so that we don't serialize
1318 */
1319 struct crypto_shash **auth_hmacs;
1320
1321 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1322 struct sctp_hmac_algo_param *auth_hmacs_list;
1323
1324 /* SCTP-AUTH: chunks to authenticate encoded into parameter */
1325 struct sctp_chunks_param *auth_chunk_list;
1326
1327 /* SCTP-AUTH: endpoint shared keys */
1328 struct list_head endpoint_shared_keys;
1329 __u16 active_key_id;
1330 __u8 ecn_enable:1,
1331 auth_enable:1,
1332 intl_enable:1,
1333 prsctp_enable:1,
1334 asconf_enable:1,
1335 reconf_enable:1;
1336
1337 __u8 strreset_enable;
1338
1339 /* Security identifiers from incoming (INIT). These are set by
1340 * security_sctp_assoc_request(). These will only be used by
1341 * SCTP TCP type sockets and peeled off connections as they
1342 * cause a new socket to be generated. security_sctp_sk_clone()
1343 * will then plug these into the new socket.
1344 */
1345
1346 u32 secid;
1347 u32 peer_secid;
1348 struct rcu_head rcu;
1349 };
1350
1351 /* Recover the outter endpoint structure. */
sctp_ep(struct sctp_ep_common * base)1352 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1353 {
1354 struct sctp_endpoint *ep;
1355
1356 ep = container_of(base, struct sctp_endpoint, base);
1357 return ep;
1358 }
1359
1360 /* These are function signatures for manipulating endpoints. */
1361 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1362 void sctp_endpoint_free(struct sctp_endpoint *);
1363 void sctp_endpoint_put(struct sctp_endpoint *);
1364 int sctp_endpoint_hold(struct sctp_endpoint *ep);
1365 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1366 struct sctp_association *sctp_endpoint_lookup_assoc(
1367 const struct sctp_endpoint *ep,
1368 const union sctp_addr *paddr,
1369 struct sctp_transport **);
1370 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep,
1371 const union sctp_addr *paddr);
1372 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1373 struct net *, const union sctp_addr *);
1374 bool sctp_has_association(struct net *net, const union sctp_addr *laddr,
1375 const union sctp_addr *paddr);
1376
1377 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep,
1378 const struct sctp_association *asoc,
1379 enum sctp_cid cid, struct sctp_init_chunk *peer_init,
1380 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk);
1381 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk,
1382 const union sctp_addr *peer,
1383 struct sctp_init_chunk *init, gfp_t gfp);
1384 __u32 sctp_generate_tag(const struct sctp_endpoint *);
1385 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
1386
1387 struct sctp_inithdr_host {
1388 __u32 init_tag;
1389 __u32 a_rwnd;
1390 __u16 num_outbound_streams;
1391 __u16 num_inbound_streams;
1392 __u32 initial_tsn;
1393 };
1394
1395 struct sctp_stream_priorities {
1396 /* List of priorities scheduled */
1397 struct list_head prio_sched;
1398 /* List of streams scheduled */
1399 struct list_head active;
1400 /* The next stream stream in line */
1401 struct sctp_stream_out_ext *next;
1402 __u16 prio;
1403 __u16 users;
1404 };
1405
1406 struct sctp_stream_out_ext {
1407 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1];
1408 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1];
1409 struct list_head outq; /* chunks enqueued by this stream */
1410 union {
1411 struct {
1412 /* Scheduled streams list */
1413 struct list_head prio_list;
1414 struct sctp_stream_priorities *prio_head;
1415 };
1416 /* Fields used by RR scheduler */
1417 struct {
1418 struct list_head rr_list;
1419 };
1420 };
1421 };
1422
1423 struct sctp_stream_out {
1424 union {
1425 __u32 mid;
1426 __u16 ssn;
1427 };
1428 __u32 mid_uo;
1429 struct sctp_stream_out_ext *ext;
1430 __u8 state;
1431 };
1432
1433 struct sctp_stream_in {
1434 union {
1435 __u32 mid;
1436 __u16 ssn;
1437 };
1438 __u32 mid_uo;
1439 __u32 fsn;
1440 __u32 fsn_uo;
1441 char pd_mode;
1442 char pd_mode_uo;
1443 };
1444
1445 struct sctp_stream {
1446 GENRADIX(struct sctp_stream_out) out;
1447 GENRADIX(struct sctp_stream_in) in;
1448
1449 __u16 outcnt;
1450 __u16 incnt;
1451 /* Current stream being sent, if any */
1452 struct sctp_stream_out *out_curr;
1453 union {
1454 /* Fields used by priority scheduler */
1455 struct {
1456 /* List of priorities scheduled */
1457 struct list_head prio_list;
1458 };
1459 /* Fields used by RR scheduler */
1460 struct {
1461 /* List of streams scheduled */
1462 struct list_head rr_list;
1463 /* The next stream stream in line */
1464 struct sctp_stream_out_ext *rr_next;
1465 };
1466 };
1467 struct sctp_stream_interleave *si;
1468 };
1469
sctp_stream_out(struct sctp_stream * stream,__u16 sid)1470 static inline struct sctp_stream_out *sctp_stream_out(
1471 struct sctp_stream *stream,
1472 __u16 sid)
1473 {
1474 return genradix_ptr(&stream->out, sid);
1475 }
1476
sctp_stream_in(struct sctp_stream * stream,__u16 sid)1477 static inline struct sctp_stream_in *sctp_stream_in(
1478 struct sctp_stream *stream,
1479 __u16 sid)
1480 {
1481 return genradix_ptr(&stream->in, sid);
1482 }
1483
1484 #define SCTP_SO(s, i) sctp_stream_out((s), (i))
1485 #define SCTP_SI(s, i) sctp_stream_in((s), (i))
1486
1487 #define SCTP_STREAM_CLOSED 0x00
1488 #define SCTP_STREAM_OPEN 0x01
1489
sctp_datachk_len(const struct sctp_stream * stream)1490 static inline __u16 sctp_datachk_len(const struct sctp_stream *stream)
1491 {
1492 return stream->si->data_chunk_len;
1493 }
1494
sctp_datahdr_len(const struct sctp_stream * stream)1495 static inline __u16 sctp_datahdr_len(const struct sctp_stream *stream)
1496 {
1497 return stream->si->data_chunk_len - sizeof(struct sctp_chunkhdr);
1498 }
1499
sctp_ftsnchk_len(const struct sctp_stream * stream)1500 static inline __u16 sctp_ftsnchk_len(const struct sctp_stream *stream)
1501 {
1502 return stream->si->ftsn_chunk_len;
1503 }
1504
sctp_ftsnhdr_len(const struct sctp_stream * stream)1505 static inline __u16 sctp_ftsnhdr_len(const struct sctp_stream *stream)
1506 {
1507 return stream->si->ftsn_chunk_len - sizeof(struct sctp_chunkhdr);
1508 }
1509
1510 /* SCTP_GET_ASSOC_STATS counters */
1511 struct sctp_priv_assoc_stats {
1512 /* Maximum observed rto in the association during subsequent
1513 * observations. Value is set to 0 if no RTO measurement took place
1514 * The transport where the max_rto was observed is returned in
1515 * obs_rto_ipaddr
1516 */
1517 struct sockaddr_storage obs_rto_ipaddr;
1518 __u64 max_obs_rto;
1519 /* Total In and Out SACKs received and sent */
1520 __u64 isacks;
1521 __u64 osacks;
1522 /* Total In and Out packets received and sent */
1523 __u64 opackets;
1524 __u64 ipackets;
1525 /* Total retransmitted chunks */
1526 __u64 rtxchunks;
1527 /* TSN received > next expected */
1528 __u64 outofseqtsns;
1529 /* Duplicate Chunks received */
1530 __u64 idupchunks;
1531 /* Gap Ack Blocks received */
1532 __u64 gapcnt;
1533 /* Unordered data chunks sent and received */
1534 __u64 ouodchunks;
1535 __u64 iuodchunks;
1536 /* Ordered data chunks sent and received */
1537 __u64 oodchunks;
1538 __u64 iodchunks;
1539 /* Control chunks sent and received */
1540 __u64 octrlchunks;
1541 __u64 ictrlchunks;
1542 };
1543
1544 /* RFC2960
1545 *
1546 * 12. Recommended Transmission Control Block (TCB) Parameters
1547 *
1548 * This section details a recommended set of parameters that should
1549 * be contained within the TCB for an implementation. This section is
1550 * for illustrative purposes and should not be deemed as requirements
1551 * on an implementation or as an exhaustive list of all parameters
1552 * inside an SCTP TCB. Each implementation may need its own additional
1553 * parameters for optimization.
1554 */
1555
1556
1557 /* Here we have information about each individual association. */
1558 struct sctp_association {
1559
1560 /* A base structure common to endpoint and association.
1561 * In this context, it represents the associations's view
1562 * of the local endpoint of the association.
1563 */
1564 struct sctp_ep_common base;
1565
1566 /* Associations on the same socket. */
1567 struct list_head asocs;
1568
1569 /* association id. */
1570 sctp_assoc_t assoc_id;
1571
1572 /* This is our parent endpoint. */
1573 struct sctp_endpoint *ep;
1574
1575 /* These are those association elements needed in the cookie. */
1576 struct sctp_cookie c;
1577
1578 /* This is all information about our peer. */
1579 struct {
1580 /* transport_addr_list
1581 *
1582 * Peer : A list of SCTP transport addresses that the
1583 * Transport : peer is bound to. This information is derived
1584 * Address : from the INIT or INIT ACK and is used to
1585 * List : associate an inbound packet with a given
1586 * : association. Normally this information is
1587 * : hashed or keyed for quick lookup and access
1588 * : of the TCB.
1589 * : The list is also initialized with the list
1590 * : of addresses passed with the sctp_connectx()
1591 * : call.
1592 *
1593 * It is a list of SCTP_transport's.
1594 */
1595 struct list_head transport_addr_list;
1596
1597 /* rwnd
1598 *
1599 * Peer Rwnd : Current calculated value of the peer's rwnd.
1600 */
1601 __u32 rwnd;
1602
1603 /* transport_count
1604 *
1605 * Peer : A count of the number of peer addresses
1606 * Transport : in the Peer Transport Address List.
1607 * Address :
1608 * Count :
1609 */
1610 __u16 transport_count;
1611
1612 /* port
1613 * The transport layer port number.
1614 */
1615 __u16 port;
1616
1617 /* primary_path
1618 *
1619 * Primary : This is the current primary destination
1620 * Path : transport address of the peer endpoint. It
1621 * : may also specify a source transport address
1622 * : on this endpoint.
1623 *
1624 * All of these paths live on transport_addr_list.
1625 *
1626 * At the bakeoffs, we discovered that the intent of
1627 * primaryPath is that it only changes when the ULP
1628 * asks to have it changed. We add the activePath to
1629 * designate the connection we are currently using to
1630 * transmit new data and most control chunks.
1631 */
1632 struct sctp_transport *primary_path;
1633
1634 /* Cache the primary path address here, when we
1635 * need a an address for msg_name.
1636 */
1637 union sctp_addr primary_addr;
1638
1639 /* active_path
1640 * The path that we are currently using to
1641 * transmit new data and most control chunks.
1642 */
1643 struct sctp_transport *active_path;
1644
1645 /* retran_path
1646 *
1647 * RFC2960 6.4 Multi-homed SCTP Endpoints
1648 * ...
1649 * Furthermore, when its peer is multi-homed, an
1650 * endpoint SHOULD try to retransmit a chunk to an
1651 * active destination transport address that is
1652 * different from the last destination address to
1653 * which the DATA chunk was sent.
1654 */
1655 struct sctp_transport *retran_path;
1656
1657 /* Pointer to last transport I have sent on. */
1658 struct sctp_transport *last_sent_to;
1659
1660 /* This is the last transport I have received DATA on. */
1661 struct sctp_transport *last_data_from;
1662
1663 /*
1664 * Mapping An array of bits or bytes indicating which out of
1665 * Array order TSN's have been received (relative to the
1666 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1667 * order packets have been received, this array
1668 * will be set to all zero. This structure may be
1669 * in the form of a circular buffer or bit array.
1670 *
1671 * Last Rcvd : This is the last TSN received in
1672 * TSN : sequence. This value is set initially by
1673 * : taking the peer's Initial TSN, received in
1674 * : the INIT or INIT ACK chunk, and subtracting
1675 * : one from it.
1676 *
1677 * Throughout most of the specification this is called the
1678 * "Cumulative TSN ACK Point". In this case, we
1679 * ignore the advice in 12.2 in favour of the term
1680 * used in the bulk of the text. This value is hidden
1681 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1682 */
1683 struct sctp_tsnmap tsn_map;
1684
1685 /* This mask is used to disable sending the ASCONF chunk
1686 * with specified parameter to peer.
1687 */
1688 __be16 addip_disabled_mask;
1689
1690 /* These are capabilities which our peer advertised. */
1691 __u16 ecn_capable:1, /* Can peer do ECN? */
1692 ipv4_address:1, /* Peer understands IPv4 addresses? */
1693 ipv6_address:1, /* Peer understands IPv6 addresses? */
1694 hostname_address:1, /* Peer understands DNS addresses? */
1695 asconf_capable:1, /* Does peer support ADDIP? */
1696 prsctp_capable:1, /* Can peer do PR-SCTP? */
1697 reconf_capable:1, /* Can peer do RE-CONFIG? */
1698 intl_capable:1, /* Can peer do INTERLEAVE */
1699 auth_capable:1, /* Is peer doing SCTP-AUTH? */
1700 /* sack_needed:
1701 * This flag indicates if the next received
1702 * packet is to be responded to with a
1703 * SACK. This is initialized to 0. When a packet
1704 * is received sack_cnt is incremented. If this value
1705 * reaches 2 or more, a SACK is sent and the
1706 * value is reset to 0. Note: This is used only
1707 * when no DATA chunks are received out of
1708 * order. When DATA chunks are out of order,
1709 * SACK's are not delayed (see Section 6).
1710 */
1711 sack_needed:1, /* Do we need to sack the peer? */
1712 sack_generation:1,
1713 zero_window_announced:1;
1714
1715 __u32 sack_cnt;
1716
1717 __u32 adaptation_ind; /* Adaptation Code point. */
1718
1719 struct sctp_inithdr_host i;
1720 void *cookie;
1721 int cookie_len;
1722
1723 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1724 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1725 * Initial TSN Value minus 1
1726 */
1727 __u32 addip_serial;
1728
1729 /* SCTP-AUTH: We need to know pears random number, hmac list
1730 * and authenticated chunk list. All that is part of the
1731 * cookie and these are just pointers to those locations
1732 */
1733 struct sctp_random_param *peer_random;
1734 struct sctp_chunks_param *peer_chunks;
1735 struct sctp_hmac_algo_param *peer_hmacs;
1736 } peer;
1737
1738 /* State : A state variable indicating what state the
1739 * : association is in, i.e. COOKIE-WAIT,
1740 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1741 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1742 *
1743 * Note: No "CLOSED" state is illustrated since if a
1744 * association is "CLOSED" its TCB SHOULD be removed.
1745 *
1746 * In this implementation we DO have a CLOSED
1747 * state which is used during initiation and shutdown.
1748 *
1749 * State takes values from SCTP_STATE_*.
1750 */
1751 enum sctp_state state;
1752
1753 /* Overall : The overall association error count.
1754 * Error Count : [Clear this any time I get something.]
1755 */
1756 int overall_error_count;
1757
1758 /* The cookie life I award for any cookie. */
1759 ktime_t cookie_life;
1760
1761 /* These are the association's initial, max, and min RTO values.
1762 * These values will be initialized by system defaults, but can
1763 * be modified via the SCTP_RTOINFO socket option.
1764 */
1765 unsigned long rto_initial;
1766 unsigned long rto_max;
1767 unsigned long rto_min;
1768
1769 /* Maximum number of new data packets that can be sent in a burst. */
1770 int max_burst;
1771
1772 /* This is the max_retrans value for the association. This value will
1773 * be initialized initialized from system defaults, but can be
1774 * modified by the SCTP_ASSOCINFO socket option.
1775 */
1776 int max_retrans;
1777
1778 /* This is the partially failed retrans value for the transport
1779 * and will be initialized from the assocs value. This can be
1780 * changed using the SCTP_PEER_ADDR_THLDS socket option
1781 */
1782 int pf_retrans;
1783
1784 /* Maximum number of times the endpoint will retransmit INIT */
1785 __u16 max_init_attempts;
1786
1787 /* How many times have we resent an INIT? */
1788 __u16 init_retries;
1789
1790 /* The largest timeout or RTO value to use in attempting an INIT */
1791 unsigned long max_init_timeo;
1792
1793 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1794 * the destination address every heartbeat interval. This value
1795 * will be inherited by all new transports.
1796 */
1797 unsigned long hbinterval;
1798
1799 /* This is the max_retrans value for new transports in the
1800 * association.
1801 */
1802 __u16 pathmaxrxt;
1803
1804 __u32 flowlabel;
1805 __u8 dscp;
1806
1807 /* Flag that path mtu update is pending */
1808 __u8 pmtu_pending;
1809
1810 /* Association : The smallest PMTU discovered for all of the
1811 * PMTU : peer's transport addresses.
1812 */
1813 __u32 pathmtu;
1814
1815 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1816 __u32 param_flags;
1817
1818 __u32 sackfreq;
1819 /* SACK delay timeout */
1820 unsigned long sackdelay;
1821
1822 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES];
1823 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1824
1825 /* Transport to which SHUTDOWN chunk was last sent. */
1826 struct sctp_transport *shutdown_last_sent_to;
1827
1828 /* Transport to which INIT chunk was last sent. */
1829 struct sctp_transport *init_last_sent_to;
1830
1831 /* How many times have we resent a SHUTDOWN */
1832 int shutdown_retries;
1833
1834 /* Next TSN : The next TSN number to be assigned to a new
1835 * : DATA chunk. This is sent in the INIT or INIT
1836 * : ACK chunk to the peer and incremented each
1837 * : time a DATA chunk is assigned a TSN
1838 * : (normally just prior to transmit or during
1839 * : fragmentation).
1840 */
1841 __u32 next_tsn;
1842
1843 /*
1844 * Last Rcvd : This is the last TSN received in sequence. This value
1845 * TSN : is set initially by taking the peer's Initial TSN,
1846 * : received in the INIT or INIT ACK chunk, and
1847 * : subtracting one from it.
1848 *
1849 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1850 */
1851
1852 __u32 ctsn_ack_point;
1853
1854 /* PR-SCTP Advanced.Peer.Ack.Point */
1855 __u32 adv_peer_ack_point;
1856
1857 /* Highest TSN that is acknowledged by incoming SACKs. */
1858 __u32 highest_sacked;
1859
1860 /* TSN marking the fast recovery exit point */
1861 __u32 fast_recovery_exit;
1862
1863 /* Flag to track the current fast recovery state */
1864 __u8 fast_recovery;
1865
1866 /* The number of unacknowledged data chunks. Reported through
1867 * the SCTP_STATUS sockopt.
1868 */
1869 __u16 unack_data;
1870
1871 /* The total number of data chunks that we've had to retransmit
1872 * as the result of a T3 timer expiration
1873 */
1874 __u32 rtx_data_chunks;
1875
1876 /* This is the association's receive buffer space. This value is used
1877 * to set a_rwnd field in an INIT or a SACK chunk.
1878 */
1879 __u32 rwnd;
1880
1881 /* This is the last advertised value of rwnd over a SACK chunk. */
1882 __u32 a_rwnd;
1883
1884 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1885 * to slop over a maximum of the association's frag_point.
1886 */
1887 __u32 rwnd_over;
1888
1889 /* Keeps treack of rwnd pressure. This happens when we have
1890 * a window, but not recevie buffer (i.e small packets). This one
1891 * is releases slowly (1 PMTU at a time ).
1892 */
1893 __u32 rwnd_press;
1894
1895 /* This is the sndbuf size in use for the association.
1896 * This corresponds to the sndbuf size for the association,
1897 * as specified in the sk->sndbuf.
1898 */
1899 int sndbuf_used;
1900
1901 /* This is the amount of memory that this association has allocated
1902 * in the receive path at any given time.
1903 */
1904 atomic_t rmem_alloc;
1905
1906 /* This is the wait queue head for send requests waiting on
1907 * the association sndbuf space.
1908 */
1909 wait_queue_head_t wait;
1910
1911 /* The message size at which SCTP fragmentation will occur. */
1912 __u32 frag_point;
1913 __u32 user_frag;
1914
1915 /* Counter used to count INIT errors. */
1916 int init_err_counter;
1917
1918 /* Count the number of INIT cycles (for doubling timeout). */
1919 int init_cycle;
1920
1921 /* Default send parameters. */
1922 __u16 default_stream;
1923 __u16 default_flags;
1924 __u32 default_ppid;
1925 __u32 default_context;
1926 __u32 default_timetolive;
1927
1928 /* Default receive parameters */
1929 __u32 default_rcv_context;
1930
1931 /* Stream arrays */
1932 struct sctp_stream stream;
1933
1934 /* All outbound chunks go through this structure. */
1935 struct sctp_outq outqueue;
1936
1937 /* A smart pipe that will handle reordering and fragmentation,
1938 * as well as handle passing events up to the ULP.
1939 */
1940 struct sctp_ulpq ulpq;
1941
1942 /* Last TSN that caused an ECNE Chunk to be sent. */
1943 __u32 last_ecne_tsn;
1944
1945 /* Last TSN that caused a CWR Chunk to be sent. */
1946 __u32 last_cwr_tsn;
1947
1948 /* How many duplicated TSNs have we seen? */
1949 int numduptsns;
1950
1951 /* These are to support
1952 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1953 * and Enforcement of Flow and Message Limits"
1954 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1955 * or "ADDIP" for short.
1956 */
1957
1958
1959
1960 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1961 *
1962 * R1) One and only one ASCONF Chunk MAY be in transit and
1963 * unacknowledged at any one time. If a sender, after sending
1964 * an ASCONF chunk, decides it needs to transfer another
1965 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1966 * returns from the previous ASCONF Chunk before sending a
1967 * subsequent ASCONF. Note this restriction binds each side,
1968 * so at any time two ASCONF may be in-transit on any given
1969 * association (one sent from each endpoint).
1970 *
1971 * [This is our one-and-only-one ASCONF in flight. If we do
1972 * not have an ASCONF in flight, this is NULL.]
1973 */
1974 struct sctp_chunk *addip_last_asconf;
1975
1976 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
1977 *
1978 * This is needed to implement itmes E1 - E4 of the updated
1979 * spec. Here is the justification:
1980 *
1981 * Since the peer may bundle multiple ASCONF chunks toward us,
1982 * we now need the ability to cache multiple ACKs. The section
1983 * describes in detail how they are cached and cleaned up.
1984 */
1985 struct list_head asconf_ack_list;
1986
1987 /* These ASCONF chunks are waiting to be sent.
1988 *
1989 * These chunaks can't be pushed to outqueue until receiving
1990 * ASCONF_ACK for the previous ASCONF indicated by
1991 * addip_last_asconf, so as to guarantee that only one ASCONF
1992 * is in flight at any time.
1993 *
1994 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1995 *
1996 * In defining the ASCONF Chunk transfer procedures, it is
1997 * essential that these transfers MUST NOT cause congestion
1998 * within the network. To achieve this, we place these
1999 * restrictions on the transfer of ASCONF Chunks:
2000 *
2001 * R1) One and only one ASCONF Chunk MAY be in transit and
2002 * unacknowledged at any one time. If a sender, after sending
2003 * an ASCONF chunk, decides it needs to transfer another
2004 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
2005 * returns from the previous ASCONF Chunk before sending a
2006 * subsequent ASCONF. Note this restriction binds each side,
2007 * so at any time two ASCONF may be in-transit on any given
2008 * association (one sent from each endpoint).
2009 *
2010 *
2011 * [I really think this is EXACTLY the sort of intelligence
2012 * which already resides in sctp_outq. Please move this
2013 * queue and its supporting logic down there. --piggy]
2014 */
2015 struct list_head addip_chunk_list;
2016
2017 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2018 *
2019 * A2) A serial number should be assigned to the Chunk. The
2020 * serial number SHOULD be a monotonically increasing
2021 * number. The serial number SHOULD be initialized at
2022 * the start of the association to the same value as the
2023 * Initial TSN and every time a new ASCONF chunk is created
2024 * it is incremented by one after assigning the serial number
2025 * to the newly created chunk.
2026 *
2027 * ADDIP
2028 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
2029 *
2030 * Serial Number : 32 bits (unsigned integer)
2031 *
2032 * This value represents a Serial Number for the ASCONF
2033 * Chunk. The valid range of Serial Number is from 0 to
2034 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
2035 * after reaching 4294967295.
2036 */
2037 __u32 addip_serial;
2038 int src_out_of_asoc_ok;
2039 union sctp_addr *asconf_addr_del_pending;
2040 struct sctp_transport *new_transport;
2041
2042 /* SCTP AUTH: list of the endpoint shared keys. These
2043 * keys are provided out of band by the user applicaton
2044 * and can't change during the lifetime of the association
2045 */
2046 struct list_head endpoint_shared_keys;
2047
2048 /* SCTP AUTH:
2049 * The current generated assocaition shared key (secret)
2050 */
2051 struct sctp_auth_bytes *asoc_shared_key;
2052 struct sctp_shared_key *shkey;
2053
2054 /* SCTP AUTH: hmac id of the first peer requested algorithm
2055 * that we support.
2056 */
2057 __u16 default_hmac_id;
2058
2059 __u16 active_key_id;
2060
2061 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */
2062 temp:1, /* Is it a temporary association? */
2063 force_delay:1;
2064
2065 __u8 strreset_enable;
2066 __u8 strreset_outstanding; /* request param count on the fly */
2067
2068 __u32 strreset_outseq; /* Update after receiving response */
2069 __u32 strreset_inseq; /* Update after receiving request */
2070 __u32 strreset_result[2]; /* save the results of last 2 responses */
2071
2072 struct sctp_chunk *strreset_chunk; /* save request chunk */
2073
2074 struct sctp_priv_assoc_stats stats;
2075
2076 int sent_cnt_removable;
2077
2078 __u16 subscribe;
2079
2080 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1];
2081 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1];
2082
2083 struct rcu_head rcu;
2084 };
2085
2086
2087 /* An eyecatcher for determining if we are really looking at an
2088 * association data structure.
2089 */
2090 enum {
2091 SCTP_ASSOC_EYECATCHER = 0xa550c123,
2092 };
2093
2094 /* Recover the outter association structure. */
sctp_assoc(struct sctp_ep_common * base)2095 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
2096 {
2097 struct sctp_association *asoc;
2098
2099 asoc = container_of(base, struct sctp_association, base);
2100 return asoc;
2101 }
2102
2103 /* These are function signatures for manipulating associations. */
2104
2105
2106 struct sctp_association *
2107 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk,
2108 enum sctp_scope scope, gfp_t gfp);
2109 void sctp_association_free(struct sctp_association *);
2110 void sctp_association_put(struct sctp_association *);
2111 void sctp_association_hold(struct sctp_association *);
2112
2113 struct sctp_transport *sctp_assoc_choose_alter_transport(
2114 struct sctp_association *, struct sctp_transport *);
2115 void sctp_assoc_update_retran_path(struct sctp_association *);
2116 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
2117 const union sctp_addr *);
2118 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
2119 const union sctp_addr *laddr);
2120 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
2121 const union sctp_addr *address,
2122 const gfp_t gfp,
2123 const int peer_state);
2124 void sctp_assoc_del_peer(struct sctp_association *asoc,
2125 const union sctp_addr *addr);
2126 void sctp_assoc_rm_peer(struct sctp_association *asoc,
2127 struct sctp_transport *peer);
2128 void sctp_assoc_control_transport(struct sctp_association *asoc,
2129 struct sctp_transport *transport,
2130 enum sctp_transport_cmd command,
2131 sctp_sn_error_t error);
2132 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
2133 void sctp_assoc_migrate(struct sctp_association *, struct sock *);
2134 int sctp_assoc_update(struct sctp_association *old,
2135 struct sctp_association *new);
2136
2137 __u32 sctp_association_get_next_tsn(struct sctp_association *);
2138
2139 void sctp_assoc_update_frag_point(struct sctp_association *asoc);
2140 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu);
2141 void sctp_assoc_sync_pmtu(struct sctp_association *asoc);
2142 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int);
2143 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int);
2144 void sctp_assoc_set_primary(struct sctp_association *,
2145 struct sctp_transport *);
2146 void sctp_assoc_del_nonprimary_peers(struct sctp_association *,
2147 struct sctp_transport *);
2148 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc,
2149 enum sctp_scope scope, gfp_t gfp);
2150 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
2151 struct sctp_cookie*,
2152 gfp_t gfp);
2153 int sctp_assoc_set_id(struct sctp_association *, gfp_t);
2154 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc);
2155 struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
2156 const struct sctp_association *asoc,
2157 __be32 serial);
2158 void sctp_asconf_queue_teardown(struct sctp_association *asoc);
2159
2160 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
2161 const union sctp_addr *ss2);
2162 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
2163
2164 /* A convenience structure to parse out SCTP specific CMSGs. */
2165 struct sctp_cmsgs {
2166 struct sctp_initmsg *init;
2167 struct sctp_sndrcvinfo *srinfo;
2168 struct sctp_sndinfo *sinfo;
2169 struct sctp_prinfo *prinfo;
2170 struct sctp_authinfo *authinfo;
2171 struct msghdr *addrs_msg;
2172 };
2173
2174 /* Structure for tracking memory objects */
2175 struct sctp_dbg_objcnt_entry {
2176 char *label;
2177 atomic_t *counter;
2178 };
2179
2180 #endif /* __sctp_structs_h__ */
2181