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 __be16 udp_port;
182 __be16 encap_port;
183
184 /* This is the max_retrans value for new associations. */
185 __u16 pathmaxrxt;
186
187 __u32 flowlabel;
188 __u8 dscp;
189
190 __u16 pf_retrans;
191 __u16 ps_retrans;
192
193 /* The initial Path MTU to use for new associations. */
194 __u32 pathmtu;
195
196 /* The default SACK delay timeout for new associations. */
197 __u32 sackdelay;
198 __u32 sackfreq;
199
200 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
201 __u32 param_flags;
202
203 __u32 default_ss;
204
205 struct sctp_rtoinfo rtoinfo;
206 struct sctp_paddrparams paddrparam;
207 struct sctp_assocparams assocparams;
208
209 /*
210 * These two structures must be grouped together for the usercopy
211 * whitelist region.
212 */
213 __u16 subscribe;
214 struct sctp_initmsg initmsg;
215
216 int user_frag;
217
218 __u32 autoclose;
219 __u32 adaptation_ind;
220 __u32 pd_point;
221 __u16 nodelay:1,
222 pf_expose:2,
223 reuse:1,
224 disable_fragments:1,
225 v4mapped:1,
226 frag_interleave:1,
227 recvrcvinfo:1,
228 recvnxtinfo:1,
229 data_ready_signalled:1;
230
231 atomic_t pd_mode;
232
233 /* Fields after this point will be skipped on copies, like on accept
234 * and peeloff operations
235 */
236
237 /* Receive to here while partial delivery is in effect. */
238 struct sk_buff_head pd_lobby;
239
240 struct list_head auto_asconf_list;
241 int do_auto_asconf;
242 };
243
sctp_sk(const struct sock * sk)244 static inline struct sctp_sock *sctp_sk(const struct sock *sk)
245 {
246 return (struct sctp_sock *)sk;
247 }
248
sctp_opt2sk(const struct sctp_sock * sp)249 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
250 {
251 return (struct sock *)sp;
252 }
253
254 #if IS_ENABLED(CONFIG_IPV6)
255 struct sctp6_sock {
256 struct sctp_sock sctp;
257 struct ipv6_pinfo inet6;
258 };
259 #endif /* CONFIG_IPV6 */
260
261
262 /* This is our APPLICATION-SPECIFIC state cookie.
263 * THIS IS NOT DICTATED BY THE SPECIFICATION.
264 */
265 /* These are the parts of an association which we send in the cookie.
266 * Most of these are straight out of:
267 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
268 *
269 */
270
271 struct sctp_cookie {
272
273 /* My : Tag expected in every inbound packet and sent
274 * Verification: in the INIT or INIT ACK chunk.
275 * Tag :
276 */
277 __u32 my_vtag;
278
279 /* Peer's : Tag expected in every outbound packet except
280 * Verification: in the INIT chunk.
281 * Tag :
282 */
283 __u32 peer_vtag;
284
285 /* The rest of these are not from the spec, but really need to
286 * be in the cookie.
287 */
288
289 /* My Tie Tag : Assist in discovering a restarting association. */
290 __u32 my_ttag;
291
292 /* Peer's Tie Tag: Assist in discovering a restarting association. */
293 __u32 peer_ttag;
294
295 /* When does this cookie expire? */
296 ktime_t expiration;
297
298 /* Number of inbound/outbound streams which are set
299 * and negotiated during the INIT process.
300 */
301 __u16 sinit_num_ostreams;
302 __u16 sinit_max_instreams;
303
304 /* This is the first sequence number I used. */
305 __u32 initial_tsn;
306
307 /* This holds the originating address of the INIT packet. */
308 union sctp_addr peer_addr;
309
310 /* IG Section 2.35.3
311 * Include the source port of the INIT-ACK
312 */
313 __u16 my_port;
314
315 __u8 prsctp_capable;
316
317 /* Padding for future use */
318 __u8 padding;
319
320 __u32 adaptation_ind;
321
322 __u8 auth_random[sizeof(struct sctp_paramhdr) +
323 SCTP_AUTH_RANDOM_LENGTH];
324 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2];
325 __u8 auth_chunks[sizeof(struct sctp_paramhdr) + SCTP_AUTH_MAX_CHUNKS];
326
327 /* This is a shim for my peer's INIT packet, followed by
328 * a copy of the raw address list of the association.
329 * The length of the raw address list is saved in the
330 * raw_addr_list_len field, which will be used at the time when
331 * the association TCB is re-constructed from the cookie.
332 */
333 __u32 raw_addr_list_len;
334 struct sctp_init_chunk peer_init[];
335 };
336
337
338 /* The format of our cookie that we send to our peer. */
339 struct sctp_signed_cookie {
340 __u8 signature[SCTP_SECRET_SIZE];
341 __u32 __pad; /* force sctp_cookie alignment to 64 bits */
342 struct sctp_cookie c;
343 } __packed;
344
345 /* This is another convenience type to allocate memory for address
346 * params for the maximum size and pass such structures around
347 * internally.
348 */
349 union sctp_addr_param {
350 struct sctp_paramhdr p;
351 struct sctp_ipv4addr_param v4;
352 struct sctp_ipv6addr_param v6;
353 };
354
355 /* A convenience type to allow walking through the various
356 * parameters and avoid casting all over the place.
357 */
358 union sctp_params {
359 void *v;
360 struct sctp_paramhdr *p;
361 struct sctp_cookie_preserve_param *life;
362 struct sctp_hostname_param *dns;
363 struct sctp_cookie_param *cookie;
364 struct sctp_supported_addrs_param *sat;
365 struct sctp_ipv4addr_param *v4;
366 struct sctp_ipv6addr_param *v6;
367 union sctp_addr_param *addr;
368 struct sctp_adaptation_ind_param *aind;
369 struct sctp_supported_ext_param *ext;
370 struct sctp_random_param *random;
371 struct sctp_chunks_param *chunks;
372 struct sctp_hmac_algo_param *hmac_algo;
373 struct sctp_addip_param *addip;
374 };
375
376 /* RFC 2960. Section 3.3.5 Heartbeat.
377 * Heartbeat Information: variable length
378 * The Sender-specific Heartbeat Info field should normally include
379 * information about the sender's current time when this HEARTBEAT
380 * chunk is sent and the destination transport address to which this
381 * HEARTBEAT is sent (see Section 8.3).
382 */
383 struct sctp_sender_hb_info {
384 struct sctp_paramhdr param_hdr;
385 union sctp_addr daddr;
386 unsigned long sent_at;
387 __u64 hb_nonce;
388 };
389
390 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt,
391 gfp_t gfp);
392 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid);
393 void sctp_stream_free(struct sctp_stream *stream);
394 void sctp_stream_clear(struct sctp_stream *stream);
395 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new);
396
397 /* What is the current SSN number for this stream? */
398 #define sctp_ssn_peek(stream, type, sid) \
399 (sctp_stream_##type((stream), (sid))->ssn)
400
401 /* Return the next SSN number for this stream. */
402 #define sctp_ssn_next(stream, type, sid) \
403 (sctp_stream_##type((stream), (sid))->ssn++)
404
405 /* Skip over this ssn and all below. */
406 #define sctp_ssn_skip(stream, type, sid, ssn) \
407 (sctp_stream_##type((stream), (sid))->ssn = ssn + 1)
408
409 /* What is the current MID number for this stream? */
410 #define sctp_mid_peek(stream, type, sid) \
411 (sctp_stream_##type((stream), (sid))->mid)
412
413 /* Return the next MID number for this stream. */
414 #define sctp_mid_next(stream, type, sid) \
415 (sctp_stream_##type((stream), (sid))->mid++)
416
417 /* Skip over this mid and all below. */
418 #define sctp_mid_skip(stream, type, sid, mid) \
419 (sctp_stream_##type((stream), (sid))->mid = mid + 1)
420
421 /* What is the current MID_uo number for this stream? */
422 #define sctp_mid_uo_peek(stream, type, sid) \
423 (sctp_stream_##type((stream), (sid))->mid_uo)
424
425 /* Return the next MID_uo number for this stream. */
426 #define sctp_mid_uo_next(stream, type, sid) \
427 (sctp_stream_##type((stream), (sid))->mid_uo++)
428
429 /*
430 * Pointers to address related SCTP functions.
431 * (i.e. things that depend on the address family.)
432 */
433 struct sctp_af {
434 int (*sctp_xmit) (struct sk_buff *skb,
435 struct sctp_transport *);
436 int (*setsockopt) (struct sock *sk,
437 int level,
438 int optname,
439 sockptr_t optval,
440 unsigned int optlen);
441 int (*getsockopt) (struct sock *sk,
442 int level,
443 int optname,
444 char __user *optval,
445 int __user *optlen);
446 void (*get_dst) (struct sctp_transport *t,
447 union sctp_addr *saddr,
448 struct flowi *fl,
449 struct sock *sk);
450 void (*get_saddr) (struct sctp_sock *sk,
451 struct sctp_transport *t,
452 struct flowi *fl);
453 void (*copy_addrlist) (struct list_head *,
454 struct net_device *);
455 int (*cmp_addr) (const union sctp_addr *addr1,
456 const union sctp_addr *addr2);
457 void (*addr_copy) (union sctp_addr *dst,
458 union sctp_addr *src);
459 void (*from_skb) (union sctp_addr *,
460 struct sk_buff *skb,
461 int saddr);
462 void (*from_sk) (union sctp_addr *,
463 struct sock *sk);
464 void (*from_addr_param) (union sctp_addr *,
465 union sctp_addr_param *,
466 __be16 port, int iif);
467 int (*to_addr_param) (const union sctp_addr *,
468 union sctp_addr_param *);
469 int (*addr_valid) (union sctp_addr *,
470 struct sctp_sock *,
471 const struct sk_buff *);
472 enum sctp_scope (*scope)(union sctp_addr *);
473 void (*inaddr_any) (union sctp_addr *, __be16);
474 int (*is_any) (const union sctp_addr *);
475 int (*available) (union sctp_addr *,
476 struct sctp_sock *);
477 int (*skb_iif) (const struct sk_buff *sk);
478 int (*is_ce) (const struct sk_buff *sk);
479 void (*seq_dump_addr)(struct seq_file *seq,
480 union sctp_addr *addr);
481 void (*ecn_capable)(struct sock *sk);
482 __u16 net_header_len;
483 int sockaddr_len;
484 int (*ip_options_len)(struct sock *sk);
485 sa_family_t sa_family;
486 struct list_head list;
487 };
488
489 struct sctp_af *sctp_get_af_specific(sa_family_t);
490 int sctp_register_af(struct sctp_af *);
491
492 /* Protocol family functions. */
493 struct sctp_pf {
494 void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
495 void (*skb_msgname) (struct sk_buff *, char *, int *);
496 int (*af_supported) (sa_family_t, struct sctp_sock *);
497 int (*cmp_addr) (const union sctp_addr *,
498 const union sctp_addr *,
499 struct sctp_sock *);
500 int (*bind_verify) (struct sctp_sock *, union sctp_addr *);
501 int (*send_verify) (struct sctp_sock *, union sctp_addr *);
502 int (*supported_addrs)(const struct sctp_sock *, __be16 *);
503 struct sock *(*create_accept_sk) (struct sock *sk,
504 struct sctp_association *asoc,
505 bool kern);
506 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr);
507 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk);
508 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk);
509 void (*copy_ip_options)(struct sock *sk, struct sock *newsk);
510 struct sctp_af *af;
511 };
512
513
514 /* Structure to track chunk fragments that have been acked, but peer
515 * fragments of the same message have not.
516 */
517 struct sctp_datamsg {
518 /* Chunks waiting to be submitted to lower layer. */
519 struct list_head chunks;
520 /* Reference counting. */
521 refcount_t refcnt;
522 /* When is this message no longer interesting to the peer? */
523 unsigned long expires_at;
524 /* Did the messenge fail to send? */
525 int send_error;
526 u8 send_failed:1,
527 can_delay:1, /* should this message be Nagle delayed */
528 abandoned:1; /* should this message be abandoned */
529 };
530
531 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
532 struct sctp_sndrcvinfo *,
533 struct iov_iter *);
534 void sctp_datamsg_free(struct sctp_datamsg *);
535 void sctp_datamsg_put(struct sctp_datamsg *);
536 void sctp_chunk_fail(struct sctp_chunk *, int error);
537 int sctp_chunk_abandoned(struct sctp_chunk *);
538
539 /* RFC2960 1.4 Key Terms
540 *
541 * o Chunk: A unit of information within an SCTP packet, consisting of
542 * a chunk header and chunk-specific content.
543 *
544 * As a matter of convenience, we remember the SCTP common header for
545 * each chunk as well as a few other header pointers...
546 */
547 struct sctp_chunk {
548 struct list_head list;
549
550 refcount_t refcnt;
551
552 /* How many times this chunk have been sent, for prsctp RTX policy */
553 int sent_count;
554
555 union {
556 /* This is our link to the per-transport transmitted list. */
557 struct list_head transmitted_list;
558 /* List in specific stream outq */
559 struct list_head stream_list;
560 };
561
562 /* This field is used by chunks that hold fragmented data.
563 * For the first fragment this is the list that holds the rest of
564 * fragments. For the remaining fragments, this is the link to the
565 * frag_list maintained in the first fragment.
566 */
567 struct list_head frag_list;
568
569 /* This points to the sk_buff containing the actual data. */
570 struct sk_buff *skb;
571
572 union {
573 /* In case of GSO packets, this will store the head one */
574 struct sk_buff *head_skb;
575 /* In case of auth enabled, this will point to the shkey */
576 struct sctp_shared_key *shkey;
577 };
578
579 /* These are the SCTP headers by reverse order in a packet.
580 * Note that some of these may happen more than once. In that
581 * case, we point at the "current" one, whatever that means
582 * for that level of header.
583 */
584
585 /* We point this at the FIRST TLV parameter to chunk_hdr. */
586 union sctp_params param_hdr;
587 union {
588 __u8 *v;
589 struct sctp_datahdr *data_hdr;
590 struct sctp_inithdr *init_hdr;
591 struct sctp_sackhdr *sack_hdr;
592 struct sctp_heartbeathdr *hb_hdr;
593 struct sctp_sender_hb_info *hbs_hdr;
594 struct sctp_shutdownhdr *shutdown_hdr;
595 struct sctp_signed_cookie *cookie_hdr;
596 struct sctp_ecnehdr *ecne_hdr;
597 struct sctp_cwrhdr *ecn_cwr_hdr;
598 struct sctp_errhdr *err_hdr;
599 struct sctp_addiphdr *addip_hdr;
600 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
601 struct sctp_authhdr *auth_hdr;
602 struct sctp_idatahdr *idata_hdr;
603 struct sctp_ifwdtsn_hdr *ifwdtsn_hdr;
604 } subh;
605
606 __u8 *chunk_end;
607
608 struct sctp_chunkhdr *chunk_hdr;
609 struct sctphdr *sctp_hdr;
610
611 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
612 struct sctp_sndrcvinfo sinfo;
613
614 /* Which association does this belong to? */
615 struct sctp_association *asoc;
616
617 /* What endpoint received this chunk? */
618 struct sctp_ep_common *rcvr;
619
620 /* We fill this in if we are calculating RTT. */
621 unsigned long sent_at;
622
623 /* What is the origin IP address for this chunk? */
624 union sctp_addr source;
625 /* Destination address for this chunk. */
626 union sctp_addr dest;
627
628 /* For outbound message, track all fragments for SEND_FAILED. */
629 struct sctp_datamsg *msg;
630
631 /* For an inbound chunk, this tells us where it came from.
632 * For an outbound chunk, it tells us where we'd like it to
633 * go. It is NULL if we have no preference.
634 */
635 struct sctp_transport *transport;
636
637 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO
638 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
639 * spec violates the principle premis that all chunks are processed
640 * in order.
641 */
642 struct sk_buff *auth_chunk;
643
644 #define SCTP_CAN_FRTX 0x0
645 #define SCTP_NEED_FRTX 0x1
646 #define SCTP_DONT_FRTX 0x2
647 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */
648 has_tsn:1, /* Does this chunk have a TSN yet? */
649 has_ssn:1, /* Does this chunk have a SSN yet? */
650 #define has_mid has_ssn
651 singleton:1, /* Only chunk in the packet? */
652 end_of_packet:1, /* Last chunk in the packet? */
653 ecn_ce_done:1, /* Have we processed the ECN CE bit? */
654 pdiscard:1, /* Discard the whole packet now? */
655 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */
656 data_accepted:1, /* At least 1 chunk accepted */
657 auth:1, /* IN: was auth'ed | OUT: needs auth */
658 has_asconf:1, /* IN: have seen an asconf before */
659 tsn_missing_report:2, /* Data chunk missing counter. */
660 fast_retransmit:2; /* Is this chunk fast retransmitted? */
661 };
662
663 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1)
664 void sctp_chunk_hold(struct sctp_chunk *);
665 void sctp_chunk_put(struct sctp_chunk *);
666 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len,
667 struct iov_iter *from);
668 void sctp_chunk_free(struct sctp_chunk *);
669 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
670 struct sctp_chunk *sctp_chunkify(struct sk_buff *,
671 const struct sctp_association *,
672 struct sock *, gfp_t gfp);
673 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
674 union sctp_addr *);
675 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
676
sctp_chunk_stream_no(struct sctp_chunk * ch)677 static inline __u16 sctp_chunk_stream_no(struct sctp_chunk *ch)
678 {
679 return ntohs(ch->subh.data_hdr->stream);
680 }
681
682 enum {
683 SCTP_ADDR_NEW, /* new address added to assoc/ep */
684 SCTP_ADDR_SRC, /* address can be used as source */
685 SCTP_ADDR_DEL, /* address about to be deleted */
686 };
687
688 /* This is a structure for holding either an IPv6 or an IPv4 address. */
689 struct sctp_sockaddr_entry {
690 struct list_head list;
691 struct rcu_head rcu;
692 union sctp_addr a;
693 __u8 state;
694 __u8 valid;
695 };
696
697 #define SCTP_ADDRESS_TICK_DELAY 500
698
699 /* This structure holds lists of chunks as we are assembling for
700 * transmission.
701 */
702 struct sctp_packet {
703 /* These are the SCTP header values (host order) for the packet. */
704 __u16 source_port;
705 __u16 destination_port;
706 __u32 vtag;
707
708 /* This contains the payload chunks. */
709 struct list_head chunk_list;
710
711 /* This is the overhead of the sctp and ip headers. */
712 size_t overhead;
713 /* This is the total size of all chunks INCLUDING padding. */
714 size_t size;
715 /* This is the maximum size this packet may have */
716 size_t max_size;
717
718 /* The packet is destined for this transport address.
719 * The function we finally use to pass down to the next lower
720 * layer lives in the transport structure.
721 */
722 struct sctp_transport *transport;
723
724 /* pointer to the auth chunk for this packet */
725 struct sctp_chunk *auth;
726
727 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */
728 has_sack:1, /* This packet contains a SACK chunk. */
729 has_auth:1, /* This packet contains an AUTH chunk */
730 has_data:1, /* This packet contains at least 1 DATA chunk */
731 ipfragok:1; /* So let ip fragment this packet */
732 };
733
734 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *,
735 __u16 sport, __u16 dport);
736 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
737 enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet,
738 struct sctp_chunk *chunk,
739 int one_packet, gfp_t gfp);
740 enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet,
741 struct sctp_chunk *chunk);
742 int sctp_packet_transmit(struct sctp_packet *, gfp_t);
743 void sctp_packet_free(struct sctp_packet *);
744
sctp_packet_empty(struct sctp_packet * packet)745 static inline int sctp_packet_empty(struct sctp_packet *packet)
746 {
747 return packet->size == packet->overhead;
748 }
749
750 /* This represents a remote transport address.
751 * For local transport addresses, we just use union sctp_addr.
752 *
753 * RFC2960 Section 1.4 Key Terms
754 *
755 * o Transport address: A Transport Address is traditionally defined
756 * by Network Layer address, Transport Layer protocol and Transport
757 * Layer port number. In the case of SCTP running over IP, a
758 * transport address is defined by the combination of an IP address
759 * and an SCTP port number (where SCTP is the Transport protocol).
760 *
761 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
762 *
763 * o The sender keeps a separate congestion control parameter set for
764 * each of the destination addresses it can send to (not each
765 * source-destination pair but for each destination). The parameters
766 * should decay if the address is not used for a long enough time
767 * period.
768 *
769 */
770 struct sctp_transport {
771 /* A list of transports. */
772 struct list_head transports;
773 struct rhlist_head node;
774
775 /* Reference counting. */
776 refcount_t refcnt;
777 /* RTO-Pending : A flag used to track if one of the DATA
778 * chunks sent to this address is currently being
779 * used to compute a RTT. If this flag is 0,
780 * the next DATA chunk sent to this destination
781 * should be used to compute a RTT and this flag
782 * should be set. Every time the RTT
783 * calculation completes (i.e. the DATA chunk
784 * is SACK'd) clear this flag.
785 */
786 __u32 rto_pending:1,
787
788 /*
789 * hb_sent : a flag that signals that we have a pending
790 * heartbeat.
791 */
792 hb_sent:1,
793
794 /* Is the Path MTU update pending on this tranport */
795 pmtu_pending:1,
796
797 dst_pending_confirm:1, /* need to confirm neighbour */
798
799 /* Has this transport moved the ctsn since we last sacked */
800 sack_generation:1;
801 u32 dst_cookie;
802
803 struct flowi fl;
804
805 /* This is the peer's IP address and port. */
806 union sctp_addr ipaddr;
807
808 /* These are the functions we call to handle LLP stuff. */
809 struct sctp_af *af_specific;
810
811 /* Which association do we belong to? */
812 struct sctp_association *asoc;
813
814 /* RFC2960
815 *
816 * 12.3 Per Transport Address Data
817 *
818 * For each destination transport address in the peer's
819 * address list derived from the INIT or INIT ACK chunk, a
820 * number of data elements needs to be maintained including:
821 */
822 /* RTO : The current retransmission timeout value. */
823 unsigned long rto;
824
825 __u32 rtt; /* This is the most recent RTT. */
826
827 /* RTTVAR : The current RTT variation. */
828 __u32 rttvar;
829
830 /* SRTT : The current smoothed round trip time. */
831 __u32 srtt;
832
833 /*
834 * These are the congestion stats.
835 */
836 /* cwnd : The current congestion window. */
837 __u32 cwnd; /* This is the actual cwnd. */
838
839 /* ssthresh : The current slow start threshold value. */
840 __u32 ssthresh;
841
842 /* partial : The tracking method for increase of cwnd when in
843 * bytes acked : congestion avoidance mode (see Section 6.2.2)
844 */
845 __u32 partial_bytes_acked;
846
847 /* Data that has been sent, but not acknowledged. */
848 __u32 flight_size;
849
850 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */
851
852 /* Destination */
853 struct dst_entry *dst;
854 /* Source address. */
855 union sctp_addr saddr;
856
857 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
858 * the destination address every heartbeat interval.
859 */
860 unsigned long hbinterval;
861
862 /* SACK delay timeout */
863 unsigned long sackdelay;
864 __u32 sackfreq;
865
866 atomic_t mtu_info;
867
868 /* When was the last time that we heard from this transport? We use
869 * this to pick new active and retran paths.
870 */
871 ktime_t last_time_heard;
872
873 /* When was the last time that we sent a chunk using this
874 * transport? We use this to check for idle transports
875 */
876 unsigned long last_time_sent;
877
878 /* Last time(in jiffies) when cwnd is reduced due to the congestion
879 * indication based on ECNE chunk.
880 */
881 unsigned long last_time_ecne_reduced;
882
883 __be16 encap_port;
884
885 /* This is the max_retrans value for the transport and will
886 * be initialized from the assocs value. This can be changed
887 * using the SCTP_SET_PEER_ADDR_PARAMS socket option.
888 */
889 __u16 pathmaxrxt;
890
891 __u32 flowlabel;
892 __u8 dscp;
893
894 /* This is the partially failed retrans value for the transport
895 * and will be initialized from the assocs value. This can be changed
896 * using the SCTP_PEER_ADDR_THLDS socket option
897 */
898 __u16 pf_retrans;
899 /* Used for primary path switchover. */
900 __u16 ps_retrans;
901 /* PMTU : The current known path MTU. */
902 __u32 pathmtu;
903
904 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
905 __u32 param_flags;
906
907 /* The number of times INIT has been sent on this transport. */
908 int init_sent_count;
909
910 /* state : The current state of this destination,
911 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
912 */
913 int state;
914
915 /* These are the error stats for this destination. */
916
917 /* Error count : The current error count for this destination. */
918 unsigned short error_count;
919
920 /* Per : A timer used by each destination.
921 * Destination :
922 * Timer :
923 *
924 * [Everywhere else in the text this is called T3-rtx. -ed]
925 */
926 struct timer_list T3_rtx_timer;
927
928 /* Heartbeat timer is per destination. */
929 struct timer_list hb_timer;
930
931 /* Timer to handle ICMP proto unreachable envets */
932 struct timer_list proto_unreach_timer;
933
934 /* Timer to handler reconf chunk rtx */
935 struct timer_list reconf_timer;
936
937 /* Since we're using per-destination retransmission timers
938 * (see above), we're also using per-destination "transmitted"
939 * queues. This probably ought to be a private struct
940 * accessible only within the outqueue, but it's not, yet.
941 */
942 struct list_head transmitted;
943
944 /* We build bundle-able packets for this transport here. */
945 struct sctp_packet packet;
946
947 /* This is the list of transports that have chunks to send. */
948 struct list_head send_ready;
949
950 /* State information saved for SFR_CACC algorithm. The key
951 * idea in SFR_CACC is to maintain state at the sender on a
952 * per-destination basis when a changeover happens.
953 * char changeover_active;
954 * char cycling_changeover;
955 * __u32 next_tsn_at_change;
956 * char cacc_saw_newack;
957 */
958 struct {
959 /* An unsigned integer, which stores the next TSN to be
960 * used by the sender, at the moment of changeover.
961 */
962 __u32 next_tsn_at_change;
963
964 /* A flag which indicates the occurrence of a changeover */
965 char changeover_active;
966
967 /* A flag which indicates whether the change of primary is
968 * the first switch to this destination address during an
969 * active switch.
970 */
971 char cycling_changeover;
972
973 /* A temporary flag, which is used during the processing of
974 * a SACK to estimate the causative TSN(s)'s group.
975 */
976 char cacc_saw_newack;
977 } cacc;
978
979 /* 64-bit random number sent with heartbeat. */
980 __u64 hb_nonce;
981
982 struct rcu_head rcu;
983 };
984
985 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *,
986 gfp_t);
987 void sctp_transport_set_owner(struct sctp_transport *,
988 struct sctp_association *);
989 void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
990 struct sctp_sock *);
991 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk);
992 void sctp_transport_free(struct sctp_transport *);
993 void sctp_transport_reset_t3_rtx(struct sctp_transport *);
994 void sctp_transport_reset_hb_timer(struct sctp_transport *);
995 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport);
996 int sctp_transport_hold(struct sctp_transport *);
997 void sctp_transport_put(struct sctp_transport *);
998 void sctp_transport_update_rto(struct sctp_transport *, __u32);
999 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
1000 void sctp_transport_lower_cwnd(struct sctp_transport *t,
1001 enum sctp_lower_cwnd reason);
1002 void sctp_transport_burst_limited(struct sctp_transport *);
1003 void sctp_transport_burst_reset(struct sctp_transport *);
1004 unsigned long sctp_transport_timeout(struct sctp_transport *);
1005 void sctp_transport_reset(struct sctp_transport *t);
1006 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu);
1007 void sctp_transport_immediate_rtx(struct sctp_transport *);
1008 void sctp_transport_dst_release(struct sctp_transport *t);
1009 void sctp_transport_dst_confirm(struct sctp_transport *t);
1010
1011
1012 /* This is the structure we use to queue packets as they come into
1013 * SCTP. We write packets to it and read chunks from it.
1014 */
1015 struct sctp_inq {
1016 /* This is actually a queue of sctp_chunk each
1017 * containing a partially decoded packet.
1018 */
1019 struct list_head in_chunk_list;
1020 /* This is the packet which is currently off the in queue and is
1021 * being worked on through the inbound chunk processing.
1022 */
1023 struct sctp_chunk *in_progress;
1024
1025 /* This is the delayed task to finish delivering inbound
1026 * messages.
1027 */
1028 struct work_struct immediate;
1029 };
1030
1031 void sctp_inq_init(struct sctp_inq *);
1032 void sctp_inq_free(struct sctp_inq *);
1033 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
1034 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
1035 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *);
1036 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t);
1037
1038 /* This is the structure we use to hold outbound chunks. You push
1039 * chunks in and they automatically pop out the other end as bundled
1040 * packets (it calls (*output_handler)()).
1041 *
1042 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1043 * and 8.2 of the v13 draft.
1044 *
1045 * It handles retransmissions. The connection to the timeout portion
1046 * of the state machine is through sctp_..._timeout() and timeout_handler.
1047 *
1048 * If you feed it SACKs, it will eat them.
1049 *
1050 * If you give it big chunks, it will fragment them.
1051 *
1052 * It assigns TSN's to data chunks. This happens at the last possible
1053 * instant before transmission.
1054 *
1055 * When free()'d, it empties itself out via output_handler().
1056 */
1057 struct sctp_outq {
1058 struct sctp_association *asoc;
1059
1060 /* Data pending that has never been transmitted. */
1061 struct list_head out_chunk_list;
1062
1063 /* Stream scheduler being used */
1064 struct sctp_sched_ops *sched;
1065
1066 unsigned int out_qlen; /* Total length of queued data chunks. */
1067
1068 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1069 unsigned int error;
1070
1071 /* These are control chunks we want to send. */
1072 struct list_head control_chunk_list;
1073
1074 /* These are chunks that have been sacked but are above the
1075 * CTSN, or cumulative tsn ack point.
1076 */
1077 struct list_head sacked;
1078
1079 /* Put chunks on this list to schedule them for
1080 * retransmission.
1081 */
1082 struct list_head retransmit;
1083
1084 /* Put chunks on this list to save them for FWD TSN processing as
1085 * they were abandoned.
1086 */
1087 struct list_head abandoned;
1088
1089 /* How many unackd bytes do we have in-flight? */
1090 __u32 outstanding_bytes;
1091
1092 /* Are we doing fast-rtx on this queue */
1093 char fast_rtx;
1094
1095 /* Corked? */
1096 char cork;
1097 };
1098
1099 void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1100 void sctp_outq_teardown(struct sctp_outq *);
1101 void sctp_outq_free(struct sctp_outq*);
1102 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t);
1103 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *);
1104 int sctp_outq_is_empty(const struct sctp_outq *);
1105 void sctp_outq_restart(struct sctp_outq *);
1106
1107 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport,
1108 enum sctp_retransmit_reason reason);
1109 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1110 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp);
1111 void sctp_prsctp_prune(struct sctp_association *asoc,
1112 struct sctp_sndrcvinfo *sinfo, int msg_len);
1113 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn);
1114 /* Uncork and flush an outqueue. */
sctp_outq_cork(struct sctp_outq * q)1115 static inline void sctp_outq_cork(struct sctp_outq *q)
1116 {
1117 q->cork = 1;
1118 }
1119
1120 /* SCTP skb control block.
1121 * sctp_input_cb is currently used on rx and sock rx queue
1122 */
1123 struct sctp_input_cb {
1124 union {
1125 struct inet_skb_parm h4;
1126 #if IS_ENABLED(CONFIG_IPV6)
1127 struct inet6_skb_parm h6;
1128 #endif
1129 } header;
1130 struct sctp_chunk *chunk;
1131 struct sctp_af *af;
1132 __be16 encap_port;
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 };
1349
1350 /* Recover the outter endpoint structure. */
sctp_ep(struct sctp_ep_common * base)1351 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1352 {
1353 struct sctp_endpoint *ep;
1354
1355 ep = container_of(base, struct sctp_endpoint, base);
1356 return ep;
1357 }
1358
1359 /* These are function signatures for manipulating endpoints. */
1360 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1361 void sctp_endpoint_free(struct sctp_endpoint *);
1362 void sctp_endpoint_put(struct sctp_endpoint *);
1363 void sctp_endpoint_hold(struct sctp_endpoint *);
1364 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1365 struct sctp_association *sctp_endpoint_lookup_assoc(
1366 const struct sctp_endpoint *ep,
1367 const union sctp_addr *paddr,
1368 struct sctp_transport **);
1369 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep,
1370 const union sctp_addr *paddr);
1371 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1372 struct net *, const union sctp_addr *);
1373 bool sctp_has_association(struct net *net, const union sctp_addr *laddr,
1374 const union sctp_addr *paddr);
1375
1376 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep,
1377 const struct sctp_association *asoc,
1378 enum sctp_cid cid, struct sctp_init_chunk *peer_init,
1379 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk);
1380 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk,
1381 const union sctp_addr *peer,
1382 struct sctp_init_chunk *init, gfp_t gfp);
1383 __u32 sctp_generate_tag(const struct sctp_endpoint *);
1384 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
1385
1386 struct sctp_inithdr_host {
1387 __u32 init_tag;
1388 __u32 a_rwnd;
1389 __u16 num_outbound_streams;
1390 __u16 num_inbound_streams;
1391 __u32 initial_tsn;
1392 };
1393
1394 struct sctp_stream_priorities {
1395 /* List of priorities scheduled */
1396 struct list_head prio_sched;
1397 /* List of streams scheduled */
1398 struct list_head active;
1399 /* The next stream in line */
1400 struct sctp_stream_out_ext *next;
1401 __u16 prio;
1402 };
1403
1404 struct sctp_stream_out_ext {
1405 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1];
1406 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1];
1407 struct list_head outq; /* chunks enqueued by this stream */
1408 union {
1409 struct {
1410 /* Scheduled streams list */
1411 struct list_head prio_list;
1412 struct sctp_stream_priorities *prio_head;
1413 };
1414 /* Fields used by RR scheduler */
1415 struct {
1416 struct list_head rr_list;
1417 };
1418 };
1419 };
1420
1421 struct sctp_stream_out {
1422 union {
1423 __u32 mid;
1424 __u16 ssn;
1425 };
1426 __u32 mid_uo;
1427 struct sctp_stream_out_ext *ext;
1428 __u8 state;
1429 };
1430
1431 struct sctp_stream_in {
1432 union {
1433 __u32 mid;
1434 __u16 ssn;
1435 };
1436 __u32 mid_uo;
1437 __u32 fsn;
1438 __u32 fsn_uo;
1439 char pd_mode;
1440 char pd_mode_uo;
1441 };
1442
1443 struct sctp_stream {
1444 GENRADIX(struct sctp_stream_out) out;
1445 GENRADIX(struct sctp_stream_in) in;
1446
1447 __u16 outcnt;
1448 __u16 incnt;
1449 /* Current stream being sent, if any */
1450 struct sctp_stream_out *out_curr;
1451 union {
1452 /* Fields used by priority scheduler */
1453 struct {
1454 /* List of priorities scheduled */
1455 struct list_head prio_list;
1456 };
1457 /* Fields used by RR scheduler */
1458 struct {
1459 /* List of streams scheduled */
1460 struct list_head rr_list;
1461 /* The next stream in line */
1462 struct sctp_stream_out_ext *rr_next;
1463 };
1464 };
1465 struct sctp_stream_interleave *si;
1466 };
1467
sctp_stream_out(struct sctp_stream * stream,__u16 sid)1468 static inline struct sctp_stream_out *sctp_stream_out(
1469 struct sctp_stream *stream,
1470 __u16 sid)
1471 {
1472 return genradix_ptr(&stream->out, sid);
1473 }
1474
sctp_stream_in(struct sctp_stream * stream,__u16 sid)1475 static inline struct sctp_stream_in *sctp_stream_in(
1476 struct sctp_stream *stream,
1477 __u16 sid)
1478 {
1479 return genradix_ptr(&stream->in, sid);
1480 }
1481
1482 #define SCTP_SO(s, i) sctp_stream_out((s), (i))
1483 #define SCTP_SI(s, i) sctp_stream_in((s), (i))
1484
1485 #define SCTP_STREAM_CLOSED 0x00
1486 #define SCTP_STREAM_OPEN 0x01
1487
sctp_datachk_len(const struct sctp_stream * stream)1488 static inline __u16 sctp_datachk_len(const struct sctp_stream *stream)
1489 {
1490 return stream->si->data_chunk_len;
1491 }
1492
sctp_datahdr_len(const struct sctp_stream * stream)1493 static inline __u16 sctp_datahdr_len(const struct sctp_stream *stream)
1494 {
1495 return stream->si->data_chunk_len - sizeof(struct sctp_chunkhdr);
1496 }
1497
sctp_ftsnchk_len(const struct sctp_stream * stream)1498 static inline __u16 sctp_ftsnchk_len(const struct sctp_stream *stream)
1499 {
1500 return stream->si->ftsn_chunk_len;
1501 }
1502
sctp_ftsnhdr_len(const struct sctp_stream * stream)1503 static inline __u16 sctp_ftsnhdr_len(const struct sctp_stream *stream)
1504 {
1505 return stream->si->ftsn_chunk_len - sizeof(struct sctp_chunkhdr);
1506 }
1507
1508 /* SCTP_GET_ASSOC_STATS counters */
1509 struct sctp_priv_assoc_stats {
1510 /* Maximum observed rto in the association during subsequent
1511 * observations. Value is set to 0 if no RTO measurement took place
1512 * The transport where the max_rto was observed is returned in
1513 * obs_rto_ipaddr
1514 */
1515 struct sockaddr_storage obs_rto_ipaddr;
1516 __u64 max_obs_rto;
1517 /* Total In and Out SACKs received and sent */
1518 __u64 isacks;
1519 __u64 osacks;
1520 /* Total In and Out packets received and sent */
1521 __u64 opackets;
1522 __u64 ipackets;
1523 /* Total retransmitted chunks */
1524 __u64 rtxchunks;
1525 /* TSN received > next expected */
1526 __u64 outofseqtsns;
1527 /* Duplicate Chunks received */
1528 __u64 idupchunks;
1529 /* Gap Ack Blocks received */
1530 __u64 gapcnt;
1531 /* Unordered data chunks sent and received */
1532 __u64 ouodchunks;
1533 __u64 iuodchunks;
1534 /* Ordered data chunks sent and received */
1535 __u64 oodchunks;
1536 __u64 iodchunks;
1537 /* Control chunks sent and received */
1538 __u64 octrlchunks;
1539 __u64 ictrlchunks;
1540 };
1541
1542 /* RFC2960
1543 *
1544 * 12. Recommended Transmission Control Block (TCB) Parameters
1545 *
1546 * This section details a recommended set of parameters that should
1547 * be contained within the TCB for an implementation. This section is
1548 * for illustrative purposes and should not be deemed as requirements
1549 * on an implementation or as an exhaustive list of all parameters
1550 * inside an SCTP TCB. Each implementation may need its own additional
1551 * parameters for optimization.
1552 */
1553
1554
1555 /* Here we have information about each individual association. */
1556 struct sctp_association {
1557
1558 /* A base structure common to endpoint and association.
1559 * In this context, it represents the associations's view
1560 * of the local endpoint of the association.
1561 */
1562 struct sctp_ep_common base;
1563
1564 /* Associations on the same socket. */
1565 struct list_head asocs;
1566
1567 /* association id. */
1568 sctp_assoc_t assoc_id;
1569
1570 /* This is our parent endpoint. */
1571 struct sctp_endpoint *ep;
1572
1573 /* These are those association elements needed in the cookie. */
1574 struct sctp_cookie c;
1575
1576 /* This is all information about our peer. */
1577 struct {
1578 /* transport_addr_list
1579 *
1580 * Peer : A list of SCTP transport addresses that the
1581 * Transport : peer is bound to. This information is derived
1582 * Address : from the INIT or INIT ACK and is used to
1583 * List : associate an inbound packet with a given
1584 * : association. Normally this information is
1585 * : hashed or keyed for quick lookup and access
1586 * : of the TCB.
1587 * : The list is also initialized with the list
1588 * : of addresses passed with the sctp_connectx()
1589 * : call.
1590 *
1591 * It is a list of SCTP_transport's.
1592 */
1593 struct list_head transport_addr_list;
1594
1595 /* rwnd
1596 *
1597 * Peer Rwnd : Current calculated value of the peer's rwnd.
1598 */
1599 __u32 rwnd;
1600
1601 /* transport_count
1602 *
1603 * Peer : A count of the number of peer addresses
1604 * Transport : in the Peer Transport Address List.
1605 * Address :
1606 * Count :
1607 */
1608 __u16 transport_count;
1609
1610 /* port
1611 * The transport layer port number.
1612 */
1613 __u16 port;
1614
1615 /* primary_path
1616 *
1617 * Primary : This is the current primary destination
1618 * Path : transport address of the peer endpoint. It
1619 * : may also specify a source transport address
1620 * : on this endpoint.
1621 *
1622 * All of these paths live on transport_addr_list.
1623 *
1624 * At the bakeoffs, we discovered that the intent of
1625 * primaryPath is that it only changes when the ULP
1626 * asks to have it changed. We add the activePath to
1627 * designate the connection we are currently using to
1628 * transmit new data and most control chunks.
1629 */
1630 struct sctp_transport *primary_path;
1631
1632 /* Cache the primary path address here, when we
1633 * need a an address for msg_name.
1634 */
1635 union sctp_addr primary_addr;
1636
1637 /* active_path
1638 * The path that we are currently using to
1639 * transmit new data and most control chunks.
1640 */
1641 struct sctp_transport *active_path;
1642
1643 /* retran_path
1644 *
1645 * RFC2960 6.4 Multi-homed SCTP Endpoints
1646 * ...
1647 * Furthermore, when its peer is multi-homed, an
1648 * endpoint SHOULD try to retransmit a chunk to an
1649 * active destination transport address that is
1650 * different from the last destination address to
1651 * which the DATA chunk was sent.
1652 */
1653 struct sctp_transport *retran_path;
1654
1655 /* Pointer to last transport I have sent on. */
1656 struct sctp_transport *last_sent_to;
1657
1658 /* This is the last transport I have received DATA on. */
1659 struct sctp_transport *last_data_from;
1660
1661 /*
1662 * Mapping An array of bits or bytes indicating which out of
1663 * Array order TSN's have been received (relative to the
1664 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1665 * order packets have been received, this array
1666 * will be set to all zero. This structure may be
1667 * in the form of a circular buffer or bit array.
1668 *
1669 * Last Rcvd : This is the last TSN received in
1670 * TSN : sequence. This value is set initially by
1671 * : taking the peer's Initial TSN, received in
1672 * : the INIT or INIT ACK chunk, and subtracting
1673 * : one from it.
1674 *
1675 * Throughout most of the specification this is called the
1676 * "Cumulative TSN ACK Point". In this case, we
1677 * ignore the advice in 12.2 in favour of the term
1678 * used in the bulk of the text. This value is hidden
1679 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1680 */
1681 struct sctp_tsnmap tsn_map;
1682
1683 /* This mask is used to disable sending the ASCONF chunk
1684 * with specified parameter to peer.
1685 */
1686 __be16 addip_disabled_mask;
1687
1688 /* These are capabilities which our peer advertised. */
1689 __u16 ecn_capable:1, /* Can peer do ECN? */
1690 ipv4_address:1, /* Peer understands IPv4 addresses? */
1691 ipv6_address:1, /* Peer understands IPv6 addresses? */
1692 hostname_address:1, /* Peer understands DNS addresses? */
1693 asconf_capable:1, /* Does peer support ADDIP? */
1694 prsctp_capable:1, /* Can peer do PR-SCTP? */
1695 reconf_capable:1, /* Can peer do RE-CONFIG? */
1696 intl_capable:1, /* Can peer do INTERLEAVE */
1697 auth_capable:1, /* Is peer doing SCTP-AUTH? */
1698 /* sack_needed:
1699 * This flag indicates if the next received
1700 * packet is to be responded to with a
1701 * SACK. This is initialized to 0. When a packet
1702 * is received sack_cnt is incremented. If this value
1703 * reaches 2 or more, a SACK is sent and the
1704 * value is reset to 0. Note: This is used only
1705 * when no DATA chunks are received out of
1706 * order. When DATA chunks are out of order,
1707 * SACK's are not delayed (see Section 6).
1708 */
1709 sack_needed:1, /* Do we need to sack the peer? */
1710 sack_generation:1,
1711 zero_window_announced:1;
1712
1713 __u32 sack_cnt;
1714
1715 __u32 adaptation_ind; /* Adaptation Code point. */
1716
1717 struct sctp_inithdr_host i;
1718 void *cookie;
1719 int cookie_len;
1720
1721 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1722 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1723 * Initial TSN Value minus 1
1724 */
1725 __u32 addip_serial;
1726
1727 /* SCTP-AUTH: We need to know pears random number, hmac list
1728 * and authenticated chunk list. All that is part of the
1729 * cookie and these are just pointers to those locations
1730 */
1731 struct sctp_random_param *peer_random;
1732 struct sctp_chunks_param *peer_chunks;
1733 struct sctp_hmac_algo_param *peer_hmacs;
1734 } peer;
1735
1736 /* State : A state variable indicating what state the
1737 * : association is in, i.e. COOKIE-WAIT,
1738 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1739 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1740 *
1741 * Note: No "CLOSED" state is illustrated since if a
1742 * association is "CLOSED" its TCB SHOULD be removed.
1743 *
1744 * In this implementation we DO have a CLOSED
1745 * state which is used during initiation and shutdown.
1746 *
1747 * State takes values from SCTP_STATE_*.
1748 */
1749 enum sctp_state state;
1750
1751 /* Overall : The overall association error count.
1752 * Error Count : [Clear this any time I get something.]
1753 */
1754 int overall_error_count;
1755
1756 /* The cookie life I award for any cookie. */
1757 ktime_t cookie_life;
1758
1759 /* These are the association's initial, max, and min RTO values.
1760 * These values will be initialized by system defaults, but can
1761 * be modified via the SCTP_RTOINFO socket option.
1762 */
1763 unsigned long rto_initial;
1764 unsigned long rto_max;
1765 unsigned long rto_min;
1766
1767 /* Maximum number of new data packets that can be sent in a burst. */
1768 int max_burst;
1769
1770 /* This is the max_retrans value for the association. This value will
1771 * be initialized from system defaults, but can be
1772 * modified by the SCTP_ASSOCINFO socket option.
1773 */
1774 int max_retrans;
1775
1776 /* This is the partially failed retrans value for the transport
1777 * and will be initialized from the assocs value. This can be
1778 * changed using the SCTP_PEER_ADDR_THLDS socket option
1779 */
1780 __u16 pf_retrans;
1781 /* Used for primary path switchover. */
1782 __u16 ps_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 __be16 encap_port;
1800
1801 /* This is the max_retrans value for new transports in the
1802 * association.
1803 */
1804 __u16 pathmaxrxt;
1805
1806 __u32 flowlabel;
1807 __u8 dscp;
1808
1809 /* Flag that path mtu update is pending */
1810 __u8 pmtu_pending;
1811
1812 /* Association : The smallest PMTU discovered for all of the
1813 * PMTU : peer's transport addresses.
1814 */
1815 __u32 pathmtu;
1816
1817 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1818 __u32 param_flags;
1819
1820 __u32 sackfreq;
1821 /* SACK delay timeout */
1822 unsigned long sackdelay;
1823
1824 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES];
1825 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1826
1827 /* Transport to which SHUTDOWN chunk was last sent. */
1828 struct sctp_transport *shutdown_last_sent_to;
1829
1830 /* Transport to which INIT chunk was last sent. */
1831 struct sctp_transport *init_last_sent_to;
1832
1833 /* How many times have we resent a SHUTDOWN */
1834 int shutdown_retries;
1835
1836 /* Next TSN : The next TSN number to be assigned to a new
1837 * : DATA chunk. This is sent in the INIT or INIT
1838 * : ACK chunk to the peer and incremented each
1839 * : time a DATA chunk is assigned a TSN
1840 * : (normally just prior to transmit or during
1841 * : fragmentation).
1842 */
1843 __u32 next_tsn;
1844
1845 /*
1846 * Last Rcvd : This is the last TSN received in sequence. This value
1847 * TSN : is set initially by taking the peer's Initial TSN,
1848 * : received in the INIT or INIT ACK chunk, and
1849 * : subtracting one from it.
1850 *
1851 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1852 */
1853
1854 __u32 ctsn_ack_point;
1855
1856 /* PR-SCTP Advanced.Peer.Ack.Point */
1857 __u32 adv_peer_ack_point;
1858
1859 /* Highest TSN that is acknowledged by incoming SACKs. */
1860 __u32 highest_sacked;
1861
1862 /* TSN marking the fast recovery exit point */
1863 __u32 fast_recovery_exit;
1864
1865 /* Flag to track the current fast recovery state */
1866 __u8 fast_recovery;
1867
1868 /* The number of unacknowledged data chunks. Reported through
1869 * the SCTP_STATUS sockopt.
1870 */
1871 __u16 unack_data;
1872
1873 /* The total number of data chunks that we've had to retransmit
1874 * as the result of a T3 timer expiration
1875 */
1876 __u32 rtx_data_chunks;
1877
1878 /* This is the association's receive buffer space. This value is used
1879 * to set a_rwnd field in an INIT or a SACK chunk.
1880 */
1881 __u32 rwnd;
1882
1883 /* This is the last advertised value of rwnd over a SACK chunk. */
1884 __u32 a_rwnd;
1885
1886 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1887 * to slop over a maximum of the association's frag_point.
1888 */
1889 __u32 rwnd_over;
1890
1891 /* Keeps treack of rwnd pressure. This happens when we have
1892 * a window, but not recevie buffer (i.e small packets). This one
1893 * is releases slowly (1 PMTU at a time ).
1894 */
1895 __u32 rwnd_press;
1896
1897 /* This is the sndbuf size in use for the association.
1898 * This corresponds to the sndbuf size for the association,
1899 * as specified in the sk->sndbuf.
1900 */
1901 int sndbuf_used;
1902
1903 /* This is the amount of memory that this association has allocated
1904 * in the receive path at any given time.
1905 */
1906 atomic_t rmem_alloc;
1907
1908 /* This is the wait queue head for send requests waiting on
1909 * the association sndbuf space.
1910 */
1911 wait_queue_head_t wait;
1912
1913 /* The message size at which SCTP fragmentation will occur. */
1914 __u32 frag_point;
1915 __u32 user_frag;
1916
1917 /* Counter used to count INIT errors. */
1918 int init_err_counter;
1919
1920 /* Count the number of INIT cycles (for doubling timeout). */
1921 int init_cycle;
1922
1923 /* Default send parameters. */
1924 __u16 default_stream;
1925 __u16 default_flags;
1926 __u32 default_ppid;
1927 __u32 default_context;
1928 __u32 default_timetolive;
1929
1930 /* Default receive parameters */
1931 __u32 default_rcv_context;
1932
1933 /* Stream arrays */
1934 struct sctp_stream stream;
1935
1936 /* All outbound chunks go through this structure. */
1937 struct sctp_outq outqueue;
1938
1939 /* A smart pipe that will handle reordering and fragmentation,
1940 * as well as handle passing events up to the ULP.
1941 */
1942 struct sctp_ulpq ulpq;
1943
1944 /* Last TSN that caused an ECNE Chunk to be sent. */
1945 __u32 last_ecne_tsn;
1946
1947 /* Last TSN that caused a CWR Chunk to be sent. */
1948 __u32 last_cwr_tsn;
1949
1950 /* How many duplicated TSNs have we seen? */
1951 int numduptsns;
1952
1953 /* These are to support
1954 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1955 * and Enforcement of Flow and Message Limits"
1956 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1957 * or "ADDIP" for short.
1958 */
1959
1960
1961
1962 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1963 *
1964 * R1) One and only one ASCONF Chunk MAY be in transit and
1965 * unacknowledged at any one time. If a sender, after sending
1966 * an ASCONF chunk, decides it needs to transfer another
1967 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1968 * returns from the previous ASCONF Chunk before sending a
1969 * subsequent ASCONF. Note this restriction binds each side,
1970 * so at any time two ASCONF may be in-transit on any given
1971 * association (one sent from each endpoint).
1972 *
1973 * [This is our one-and-only-one ASCONF in flight. If we do
1974 * not have an ASCONF in flight, this is NULL.]
1975 */
1976 struct sctp_chunk *addip_last_asconf;
1977
1978 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
1979 *
1980 * This is needed to implement itmes E1 - E4 of the updated
1981 * spec. Here is the justification:
1982 *
1983 * Since the peer may bundle multiple ASCONF chunks toward us,
1984 * we now need the ability to cache multiple ACKs. The section
1985 * describes in detail how they are cached and cleaned up.
1986 */
1987 struct list_head asconf_ack_list;
1988
1989 /* These ASCONF chunks are waiting to be sent.
1990 *
1991 * These chunaks can't be pushed to outqueue until receiving
1992 * ASCONF_ACK for the previous ASCONF indicated by
1993 * addip_last_asconf, so as to guarantee that only one ASCONF
1994 * is in flight at any time.
1995 *
1996 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1997 *
1998 * In defining the ASCONF Chunk transfer procedures, it is
1999 * essential that these transfers MUST NOT cause congestion
2000 * within the network. To achieve this, we place these
2001 * restrictions on the transfer of ASCONF Chunks:
2002 *
2003 * R1) One and only one ASCONF Chunk MAY be in transit and
2004 * unacknowledged at any one time. If a sender, after sending
2005 * an ASCONF chunk, decides it needs to transfer another
2006 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
2007 * returns from the previous ASCONF Chunk before sending a
2008 * subsequent ASCONF. Note this restriction binds each side,
2009 * so at any time two ASCONF may be in-transit on any given
2010 * association (one sent from each endpoint).
2011 *
2012 *
2013 * [I really think this is EXACTLY the sort of intelligence
2014 * which already resides in sctp_outq. Please move this
2015 * queue and its supporting logic down there. --piggy]
2016 */
2017 struct list_head addip_chunk_list;
2018
2019 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2020 *
2021 * A2) A serial number should be assigned to the Chunk. The
2022 * serial number SHOULD be a monotonically increasing
2023 * number. The serial number SHOULD be initialized at
2024 * the start of the association to the same value as the
2025 * Initial TSN and every time a new ASCONF chunk is created
2026 * it is incremented by one after assigning the serial number
2027 * to the newly created chunk.
2028 *
2029 * ADDIP
2030 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
2031 *
2032 * Serial Number : 32 bits (unsigned integer)
2033 *
2034 * This value represents a Serial Number for the ASCONF
2035 * Chunk. The valid range of Serial Number is from 0 to
2036 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
2037 * after reaching 4294967295.
2038 */
2039 __u32 addip_serial;
2040 int src_out_of_asoc_ok;
2041 union sctp_addr *asconf_addr_del_pending;
2042 struct sctp_transport *new_transport;
2043
2044 /* SCTP AUTH: list of the endpoint shared keys. These
2045 * keys are provided out of band by the user applicaton
2046 * and can't change during the lifetime of the association
2047 */
2048 struct list_head endpoint_shared_keys;
2049
2050 /* SCTP AUTH:
2051 * The current generated assocaition shared key (secret)
2052 */
2053 struct sctp_auth_bytes *asoc_shared_key;
2054 struct sctp_shared_key *shkey;
2055
2056 /* SCTP AUTH: hmac id of the first peer requested algorithm
2057 * that we support.
2058 */
2059 __u16 default_hmac_id;
2060
2061 __u16 active_key_id;
2062
2063 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */
2064 temp:1, /* Is it a temporary association? */
2065 pf_expose:2, /* Expose pf state? */
2066 force_delay:1;
2067
2068 __u8 strreset_enable;
2069 __u8 strreset_outstanding; /* request param count on the fly */
2070
2071 __u32 strreset_outseq; /* Update after receiving response */
2072 __u32 strreset_inseq; /* Update after receiving request */
2073 __u32 strreset_result[2]; /* save the results of last 2 responses */
2074
2075 struct sctp_chunk *strreset_chunk; /* save request chunk */
2076
2077 struct sctp_priv_assoc_stats stats;
2078
2079 int sent_cnt_removable;
2080
2081 __u16 subscribe;
2082
2083 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1];
2084 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1];
2085
2086 struct rcu_head rcu;
2087 };
2088
2089
2090 /* An eyecatcher for determining if we are really looking at an
2091 * association data structure.
2092 */
2093 enum {
2094 SCTP_ASSOC_EYECATCHER = 0xa550c123,
2095 };
2096
2097 /* Recover the outter association structure. */
sctp_assoc(struct sctp_ep_common * base)2098 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
2099 {
2100 struct sctp_association *asoc;
2101
2102 asoc = container_of(base, struct sctp_association, base);
2103 return asoc;
2104 }
2105
2106 /* These are function signatures for manipulating associations. */
2107
2108
2109 struct sctp_association *
2110 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk,
2111 enum sctp_scope scope, gfp_t gfp);
2112 void sctp_association_free(struct sctp_association *);
2113 void sctp_association_put(struct sctp_association *);
2114 void sctp_association_hold(struct sctp_association *);
2115
2116 struct sctp_transport *sctp_assoc_choose_alter_transport(
2117 struct sctp_association *, struct sctp_transport *);
2118 void sctp_assoc_update_retran_path(struct sctp_association *);
2119 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
2120 const union sctp_addr *);
2121 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
2122 const union sctp_addr *laddr);
2123 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
2124 const union sctp_addr *address,
2125 const gfp_t gfp,
2126 const int peer_state);
2127 void sctp_assoc_del_peer(struct sctp_association *asoc,
2128 const union sctp_addr *addr);
2129 void sctp_assoc_rm_peer(struct sctp_association *asoc,
2130 struct sctp_transport *peer);
2131 void sctp_assoc_control_transport(struct sctp_association *asoc,
2132 struct sctp_transport *transport,
2133 enum sctp_transport_cmd command,
2134 sctp_sn_error_t error);
2135 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
2136 void sctp_assoc_migrate(struct sctp_association *, struct sock *);
2137 int sctp_assoc_update(struct sctp_association *old,
2138 struct sctp_association *new);
2139
2140 __u32 sctp_association_get_next_tsn(struct sctp_association *);
2141
2142 void sctp_assoc_update_frag_point(struct sctp_association *asoc);
2143 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu);
2144 void sctp_assoc_sync_pmtu(struct sctp_association *asoc);
2145 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int);
2146 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int);
2147 void sctp_assoc_set_primary(struct sctp_association *,
2148 struct sctp_transport *);
2149 void sctp_assoc_del_nonprimary_peers(struct sctp_association *,
2150 struct sctp_transport *);
2151 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc,
2152 enum sctp_scope scope, gfp_t gfp);
2153 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
2154 struct sctp_cookie*,
2155 gfp_t gfp);
2156 int sctp_assoc_set_id(struct sctp_association *, gfp_t);
2157 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc);
2158 struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
2159 const struct sctp_association *asoc,
2160 __be32 serial);
2161 void sctp_asconf_queue_teardown(struct sctp_association *asoc);
2162
2163 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
2164 const union sctp_addr *ss2);
2165 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
2166
2167 /* A convenience structure to parse out SCTP specific CMSGs. */
2168 struct sctp_cmsgs {
2169 struct sctp_initmsg *init;
2170 struct sctp_sndrcvinfo *srinfo;
2171 struct sctp_sndinfo *sinfo;
2172 struct sctp_prinfo *prinfo;
2173 struct sctp_authinfo *authinfo;
2174 struct msghdr *addrs_msg;
2175 };
2176
2177 /* Structure for tracking memory objects */
2178 struct sctp_dbg_objcnt_entry {
2179 char *label;
2180 atomic_t *counter;
2181 };
2182
2183 #endif /* __sctp_structs_h__ */
2184