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 __u32 probe_interval;
181
182 __be16 udp_port;
183 __be16 encap_port;
184
185 /* This is the max_retrans value for new associations. */
186 __u16 pathmaxrxt;
187
188 __u32 flowlabel;
189 __u8 dscp;
190
191 __u16 pf_retrans;
192 __u16 ps_retrans;
193
194 /* The initial Path MTU to use for new associations. */
195 __u32 pathmtu;
196
197 /* The default SACK delay timeout for new associations. */
198 __u32 sackdelay;
199 __u32 sackfreq;
200
201 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
202 __u32 param_flags;
203
204 __u32 default_ss;
205
206 struct sctp_rtoinfo rtoinfo;
207 struct sctp_paddrparams paddrparam;
208 struct sctp_assocparams assocparams;
209
210 /*
211 * These two structures must be grouped together for the usercopy
212 * whitelist region.
213 */
214 __u16 subscribe;
215 struct sctp_initmsg initmsg;
216
217 int user_frag;
218
219 __u32 autoclose;
220 __u32 adaptation_ind;
221 __u32 pd_point;
222 __u16 nodelay:1,
223 pf_expose:2,
224 reuse:1,
225 disable_fragments:1,
226 v4mapped:1,
227 frag_interleave:1,
228 recvrcvinfo:1,
229 recvnxtinfo:1,
230 data_ready_signalled:1;
231
232 atomic_t pd_mode;
233
234 /* Fields after this point will be skipped on copies, like on accept
235 * and peeloff operations
236 */
237
238 /* Receive to here while partial delivery is in effect. */
239 struct sk_buff_head pd_lobby;
240
241 struct list_head auto_asconf_list;
242 int do_auto_asconf;
243 };
244
sctp_sk(const struct sock * sk)245 static inline struct sctp_sock *sctp_sk(const struct sock *sk)
246 {
247 return (struct sctp_sock *)sk;
248 }
249
sctp_opt2sk(const struct sctp_sock * sp)250 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
251 {
252 return (struct sock *)sp;
253 }
254
255 #if IS_ENABLED(CONFIG_IPV6)
256 struct sctp6_sock {
257 struct sctp_sock sctp;
258 struct ipv6_pinfo inet6;
259 };
260 #endif /* CONFIG_IPV6 */
261
262
263 /* This is our APPLICATION-SPECIFIC state cookie.
264 * THIS IS NOT DICTATED BY THE SPECIFICATION.
265 */
266 /* These are the parts of an association which we send in the cookie.
267 * Most of these are straight out of:
268 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
269 *
270 */
271
272 struct sctp_cookie {
273
274 /* My : Tag expected in every inbound packet and sent
275 * Verification: in the INIT or INIT ACK chunk.
276 * Tag :
277 */
278 __u32 my_vtag;
279
280 /* Peer's : Tag expected in every outbound packet except
281 * Verification: in the INIT chunk.
282 * Tag :
283 */
284 __u32 peer_vtag;
285
286 /* The rest of these are not from the spec, but really need to
287 * be in the cookie.
288 */
289
290 /* My Tie Tag : Assist in discovering a restarting association. */
291 __u32 my_ttag;
292
293 /* Peer's Tie Tag: Assist in discovering a restarting association. */
294 __u32 peer_ttag;
295
296 /* When does this cookie expire? */
297 ktime_t expiration;
298
299 /* Number of inbound/outbound streams which are set
300 * and negotiated during the INIT process.
301 */
302 __u16 sinit_num_ostreams;
303 __u16 sinit_max_instreams;
304
305 /* This is the first sequence number I used. */
306 __u32 initial_tsn;
307
308 /* This holds the originating address of the INIT packet. */
309 union sctp_addr peer_addr;
310
311 /* IG Section 2.35.3
312 * Include the source port of the INIT-ACK
313 */
314 __u16 my_port;
315
316 __u8 prsctp_capable;
317
318 /* Padding for future use */
319 __u8 padding;
320
321 __u32 adaptation_ind;
322
323 __u8 auth_random[sizeof(struct sctp_paramhdr) +
324 SCTP_AUTH_RANDOM_LENGTH];
325 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2];
326 __u8 auth_chunks[sizeof(struct sctp_paramhdr) + SCTP_AUTH_MAX_CHUNKS];
327
328 /* This is a shim for my peer's INIT packet, followed by
329 * a copy of the raw address list of the association.
330 * The length of the raw address list is saved in the
331 * raw_addr_list_len field, which will be used at the time when
332 * the association TCB is re-constructed from the cookie.
333 */
334 __u32 raw_addr_list_len;
335 struct sctp_init_chunk peer_init[];
336 };
337
338
339 /* The format of our cookie that we send to our peer. */
340 struct sctp_signed_cookie {
341 __u8 signature[SCTP_SECRET_SIZE];
342 __u32 __pad; /* force sctp_cookie alignment to 64 bits */
343 struct sctp_cookie c;
344 } __packed;
345
346 /* This is another convenience type to allocate memory for address
347 * params for the maximum size and pass such structures around
348 * internally.
349 */
350 union sctp_addr_param {
351 struct sctp_paramhdr p;
352 struct sctp_ipv4addr_param v4;
353 struct sctp_ipv6addr_param v6;
354 };
355
356 /* A convenience type to allow walking through the various
357 * parameters and avoid casting all over the place.
358 */
359 union sctp_params {
360 void *v;
361 struct sctp_paramhdr *p;
362 struct sctp_cookie_preserve_param *life;
363 struct sctp_hostname_param *dns;
364 struct sctp_cookie_param *cookie;
365 struct sctp_supported_addrs_param *sat;
366 struct sctp_ipv4addr_param *v4;
367 struct sctp_ipv6addr_param *v6;
368 union sctp_addr_param *addr;
369 struct sctp_adaptation_ind_param *aind;
370 struct sctp_supported_ext_param *ext;
371 struct sctp_random_param *random;
372 struct sctp_chunks_param *chunks;
373 struct sctp_hmac_algo_param *hmac_algo;
374 struct sctp_addip_param *addip;
375 };
376
377 /* RFC 2960. Section 3.3.5 Heartbeat.
378 * Heartbeat Information: variable length
379 * The Sender-specific Heartbeat Info field should normally include
380 * information about the sender's current time when this HEARTBEAT
381 * chunk is sent and the destination transport address to which this
382 * HEARTBEAT is sent (see Section 8.3).
383 */
384 struct sctp_sender_hb_info {
385 struct sctp_paramhdr param_hdr;
386 union sctp_addr daddr;
387 unsigned long sent_at;
388 __u64 hb_nonce;
389 __u32 probe_size;
390 };
391
392 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt,
393 gfp_t gfp);
394 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid);
395 void sctp_stream_free(struct sctp_stream *stream);
396 void sctp_stream_clear(struct sctp_stream *stream);
397 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new);
398
399 /* What is the current SSN number for this stream? */
400 #define sctp_ssn_peek(stream, type, sid) \
401 (sctp_stream_##type((stream), (sid))->ssn)
402
403 /* Return the next SSN number for this stream. */
404 #define sctp_ssn_next(stream, type, sid) \
405 (sctp_stream_##type((stream), (sid))->ssn++)
406
407 /* Skip over this ssn and all below. */
408 #define sctp_ssn_skip(stream, type, sid, ssn) \
409 (sctp_stream_##type((stream), (sid))->ssn = ssn + 1)
410
411 /* What is the current MID number for this stream? */
412 #define sctp_mid_peek(stream, type, sid) \
413 (sctp_stream_##type((stream), (sid))->mid)
414
415 /* Return the next MID number for this stream. */
416 #define sctp_mid_next(stream, type, sid) \
417 (sctp_stream_##type((stream), (sid))->mid++)
418
419 /* Skip over this mid and all below. */
420 #define sctp_mid_skip(stream, type, sid, mid) \
421 (sctp_stream_##type((stream), (sid))->mid = mid + 1)
422
423 /* What is the current MID_uo number for this stream? */
424 #define sctp_mid_uo_peek(stream, type, sid) \
425 (sctp_stream_##type((stream), (sid))->mid_uo)
426
427 /* Return the next MID_uo number for this stream. */
428 #define sctp_mid_uo_next(stream, type, sid) \
429 (sctp_stream_##type((stream), (sid))->mid_uo++)
430
431 /*
432 * Pointers to address related SCTP functions.
433 * (i.e. things that depend on the address family.)
434 */
435 struct sctp_af {
436 int (*sctp_xmit) (struct sk_buff *skb,
437 struct sctp_transport *);
438 int (*setsockopt) (struct sock *sk,
439 int level,
440 int optname,
441 sockptr_t optval,
442 unsigned int optlen);
443 int (*getsockopt) (struct sock *sk,
444 int level,
445 int optname,
446 char __user *optval,
447 int __user *optlen);
448 void (*get_dst) (struct sctp_transport *t,
449 union sctp_addr *saddr,
450 struct flowi *fl,
451 struct sock *sk);
452 void (*get_saddr) (struct sctp_sock *sk,
453 struct sctp_transport *t,
454 struct flowi *fl);
455 void (*copy_addrlist) (struct list_head *,
456 struct net_device *);
457 int (*cmp_addr) (const union sctp_addr *addr1,
458 const union sctp_addr *addr2);
459 void (*addr_copy) (union sctp_addr *dst,
460 union sctp_addr *src);
461 void (*from_skb) (union sctp_addr *,
462 struct sk_buff *skb,
463 int saddr);
464 void (*from_sk) (union sctp_addr *,
465 struct sock *sk);
466 bool (*from_addr_param) (union sctp_addr *,
467 union sctp_addr_param *,
468 __be16 port, int iif);
469 int (*to_addr_param) (const union sctp_addr *,
470 union sctp_addr_param *);
471 int (*addr_valid) (union sctp_addr *,
472 struct sctp_sock *,
473 const struct sk_buff *);
474 enum sctp_scope (*scope)(union sctp_addr *);
475 void (*inaddr_any) (union sctp_addr *, __be16);
476 int (*is_any) (const union sctp_addr *);
477 int (*available) (union sctp_addr *,
478 struct sctp_sock *);
479 int (*skb_iif) (const struct sk_buff *sk);
480 int (*is_ce) (const struct sk_buff *sk);
481 void (*seq_dump_addr)(struct seq_file *seq,
482 union sctp_addr *addr);
483 void (*ecn_capable)(struct sock *sk);
484 __u16 net_header_len;
485 int sockaddr_len;
486 int (*ip_options_len)(struct sock *sk);
487 sa_family_t sa_family;
488 struct list_head list;
489 };
490
491 struct sctp_af *sctp_get_af_specific(sa_family_t);
492 int sctp_register_af(struct sctp_af *);
493
494 /* Protocol family functions. */
495 struct sctp_pf {
496 void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
497 void (*skb_msgname) (struct sk_buff *, char *, int *);
498 int (*af_supported) (sa_family_t, struct sctp_sock *);
499 int (*cmp_addr) (const union sctp_addr *,
500 const union sctp_addr *,
501 struct sctp_sock *);
502 int (*bind_verify) (struct sctp_sock *, union sctp_addr *);
503 int (*send_verify) (struct sctp_sock *, union sctp_addr *);
504 int (*supported_addrs)(const struct sctp_sock *, __be16 *);
505 struct sock *(*create_accept_sk) (struct sock *sk,
506 struct sctp_association *asoc,
507 bool kern);
508 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr);
509 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk);
510 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk);
511 void (*copy_ip_options)(struct sock *sk, struct sock *newsk);
512 struct sctp_af *af;
513 };
514
515
516 /* Structure to track chunk fragments that have been acked, but peer
517 * fragments of the same message have not.
518 */
519 struct sctp_datamsg {
520 /* Chunks waiting to be submitted to lower layer. */
521 struct list_head chunks;
522 /* Reference counting. */
523 refcount_t refcnt;
524 /* When is this message no longer interesting to the peer? */
525 unsigned long expires_at;
526 /* Did the messenge fail to send? */
527 int send_error;
528 u8 send_failed:1,
529 can_delay:1, /* should this message be Nagle delayed */
530 abandoned:1; /* should this message be abandoned */
531 };
532
533 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
534 struct sctp_sndrcvinfo *,
535 struct iov_iter *);
536 void sctp_datamsg_free(struct sctp_datamsg *);
537 void sctp_datamsg_put(struct sctp_datamsg *);
538 void sctp_chunk_fail(struct sctp_chunk *, int error);
539 int sctp_chunk_abandoned(struct sctp_chunk *);
540
541 /* RFC2960 1.4 Key Terms
542 *
543 * o Chunk: A unit of information within an SCTP packet, consisting of
544 * a chunk header and chunk-specific content.
545 *
546 * As a matter of convenience, we remember the SCTP common header for
547 * each chunk as well as a few other header pointers...
548 */
549 struct sctp_chunk {
550 struct list_head list;
551
552 refcount_t refcnt;
553
554 /* How many times this chunk have been sent, for prsctp RTX policy */
555 int sent_count;
556
557 union {
558 /* This is our link to the per-transport transmitted list. */
559 struct list_head transmitted_list;
560 /* List in specific stream outq */
561 struct list_head stream_list;
562 };
563
564 /* This field is used by chunks that hold fragmented data.
565 * For the first fragment this is the list that holds the rest of
566 * fragments. For the remaining fragments, this is the link to the
567 * frag_list maintained in the first fragment.
568 */
569 struct list_head frag_list;
570
571 /* This points to the sk_buff containing the actual data. */
572 struct sk_buff *skb;
573
574 union {
575 /* In case of GSO packets, this will store the head one */
576 struct sk_buff *head_skb;
577 /* In case of auth enabled, this will point to the shkey */
578 struct sctp_shared_key *shkey;
579 };
580
581 /* These are the SCTP headers by reverse order in a packet.
582 * Note that some of these may happen more than once. In that
583 * case, we point at the "current" one, whatever that means
584 * for that level of header.
585 */
586
587 /* We point this at the FIRST TLV parameter to chunk_hdr. */
588 union sctp_params param_hdr;
589 union {
590 __u8 *v;
591 struct sctp_datahdr *data_hdr;
592 struct sctp_inithdr *init_hdr;
593 struct sctp_sackhdr *sack_hdr;
594 struct sctp_heartbeathdr *hb_hdr;
595 struct sctp_sender_hb_info *hbs_hdr;
596 struct sctp_shutdownhdr *shutdown_hdr;
597 struct sctp_signed_cookie *cookie_hdr;
598 struct sctp_ecnehdr *ecne_hdr;
599 struct sctp_cwrhdr *ecn_cwr_hdr;
600 struct sctp_errhdr *err_hdr;
601 struct sctp_addiphdr *addip_hdr;
602 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
603 struct sctp_authhdr *auth_hdr;
604 struct sctp_idatahdr *idata_hdr;
605 struct sctp_ifwdtsn_hdr *ifwdtsn_hdr;
606 } subh;
607
608 __u8 *chunk_end;
609
610 struct sctp_chunkhdr *chunk_hdr;
611 struct sctphdr *sctp_hdr;
612
613 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
614 struct sctp_sndrcvinfo sinfo;
615
616 /* Which association does this belong to? */
617 struct sctp_association *asoc;
618
619 /* What endpoint received this chunk? */
620 struct sctp_ep_common *rcvr;
621
622 /* We fill this in if we are calculating RTT. */
623 unsigned long sent_at;
624
625 /* What is the origin IP address for this chunk? */
626 union sctp_addr source;
627 /* Destination address for this chunk. */
628 union sctp_addr dest;
629
630 /* For outbound message, track all fragments for SEND_FAILED. */
631 struct sctp_datamsg *msg;
632
633 /* For an inbound chunk, this tells us where it came from.
634 * For an outbound chunk, it tells us where we'd like it to
635 * go. It is NULL if we have no preference.
636 */
637 struct sctp_transport *transport;
638
639 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO
640 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
641 * spec violates the principle premis that all chunks are processed
642 * in order.
643 */
644 struct sk_buff *auth_chunk;
645
646 #define SCTP_CAN_FRTX 0x0
647 #define SCTP_NEED_FRTX 0x1
648 #define SCTP_DONT_FRTX 0x2
649 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */
650 has_tsn:1, /* Does this chunk have a TSN yet? */
651 has_ssn:1, /* Does this chunk have a SSN yet? */
652 #define has_mid has_ssn
653 singleton:1, /* Only chunk in the packet? */
654 end_of_packet:1, /* Last chunk in the packet? */
655 ecn_ce_done:1, /* Have we processed the ECN CE bit? */
656 pdiscard:1, /* Discard the whole packet now? */
657 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */
658 data_accepted:1, /* At least 1 chunk accepted */
659 auth:1, /* IN: was auth'ed | OUT: needs auth */
660 has_asconf:1, /* IN: have seen an asconf before */
661 pmtu_probe:1, /* Used by PLPMTUD, can be set in s HB chunk */
662 tsn_missing_report:2, /* Data chunk missing counter. */
663 fast_retransmit:2; /* Is this chunk fast retransmitted? */
664 };
665
666 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1)
667 void sctp_chunk_hold(struct sctp_chunk *);
668 void sctp_chunk_put(struct sctp_chunk *);
669 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len,
670 struct iov_iter *from);
671 void sctp_chunk_free(struct sctp_chunk *);
672 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
673 struct sctp_chunk *sctp_chunkify(struct sk_buff *,
674 const struct sctp_association *,
675 struct sock *, gfp_t gfp);
676 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
677 union sctp_addr *);
678 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
679
sctp_chunk_stream_no(struct sctp_chunk * ch)680 static inline __u16 sctp_chunk_stream_no(struct sctp_chunk *ch)
681 {
682 return ntohs(ch->subh.data_hdr->stream);
683 }
684
685 enum {
686 SCTP_ADDR_NEW, /* new address added to assoc/ep */
687 SCTP_ADDR_SRC, /* address can be used as source */
688 SCTP_ADDR_DEL, /* address about to be deleted */
689 };
690
691 /* This is a structure for holding either an IPv6 or an IPv4 address. */
692 struct sctp_sockaddr_entry {
693 struct list_head list;
694 struct rcu_head rcu;
695 union sctp_addr a;
696 __u8 state;
697 __u8 valid;
698 };
699
700 #define SCTP_ADDRESS_TICK_DELAY 500
701
702 /* This structure holds lists of chunks as we are assembling for
703 * transmission.
704 */
705 struct sctp_packet {
706 /* These are the SCTP header values (host order) for the packet. */
707 __u16 source_port;
708 __u16 destination_port;
709 __u32 vtag;
710
711 /* This contains the payload chunks. */
712 struct list_head chunk_list;
713
714 /* This is the overhead of the sctp and ip headers. */
715 size_t overhead;
716 /* This is the total size of all chunks INCLUDING padding. */
717 size_t size;
718 /* This is the maximum size this packet may have */
719 size_t max_size;
720
721 /* The packet is destined for this transport address.
722 * The function we finally use to pass down to the next lower
723 * layer lives in the transport structure.
724 */
725 struct sctp_transport *transport;
726
727 /* pointer to the auth chunk for this packet */
728 struct sctp_chunk *auth;
729
730 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */
731 has_sack:1, /* This packet contains a SACK chunk. */
732 has_auth:1, /* This packet contains an AUTH chunk */
733 has_data:1, /* This packet contains at least 1 DATA chunk */
734 ipfragok:1; /* So let ip fragment this packet */
735 };
736
737 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *,
738 __u16 sport, __u16 dport);
739 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
740 enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet,
741 struct sctp_chunk *chunk,
742 int one_packet, gfp_t gfp);
743 enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet,
744 struct sctp_chunk *chunk);
745 int sctp_packet_transmit(struct sctp_packet *, gfp_t);
746 void sctp_packet_free(struct sctp_packet *);
747
sctp_packet_empty(struct sctp_packet * packet)748 static inline int sctp_packet_empty(struct sctp_packet *packet)
749 {
750 return packet->size == packet->overhead;
751 }
752
753 /* This represents a remote transport address.
754 * For local transport addresses, we just use union sctp_addr.
755 *
756 * RFC2960 Section 1.4 Key Terms
757 *
758 * o Transport address: A Transport Address is traditionally defined
759 * by Network Layer address, Transport Layer protocol and Transport
760 * Layer port number. In the case of SCTP running over IP, a
761 * transport address is defined by the combination of an IP address
762 * and an SCTP port number (where SCTP is the Transport protocol).
763 *
764 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
765 *
766 * o The sender keeps a separate congestion control parameter set for
767 * each of the destination addresses it can send to (not each
768 * source-destination pair but for each destination). The parameters
769 * should decay if the address is not used for a long enough time
770 * period.
771 *
772 */
773 struct sctp_transport {
774 /* A list of transports. */
775 struct list_head transports;
776 struct rhlist_head node;
777
778 /* Reference counting. */
779 refcount_t refcnt;
780 /* RTO-Pending : A flag used to track if one of the DATA
781 * chunks sent to this address is currently being
782 * used to compute a RTT. If this flag is 0,
783 * the next DATA chunk sent to this destination
784 * should be used to compute a RTT and this flag
785 * should be set. Every time the RTT
786 * calculation completes (i.e. the DATA chunk
787 * is SACK'd) clear this flag.
788 */
789 __u32 rto_pending:1,
790
791 /*
792 * hb_sent : a flag that signals that we have a pending
793 * heartbeat.
794 */
795 hb_sent:1,
796
797 /* Is the Path MTU update pending on this tranport */
798 pmtu_pending:1,
799
800 dst_pending_confirm:1, /* need to confirm neighbour */
801
802 /* Has this transport moved the ctsn since we last sacked */
803 sack_generation:1;
804 u32 dst_cookie;
805
806 struct flowi fl;
807
808 /* This is the peer's IP address and port. */
809 union sctp_addr ipaddr;
810
811 /* These are the functions we call to handle LLP stuff. */
812 struct sctp_af *af_specific;
813
814 /* Which association do we belong to? */
815 struct sctp_association *asoc;
816
817 /* RFC2960
818 *
819 * 12.3 Per Transport Address Data
820 *
821 * For each destination transport address in the peer's
822 * address list derived from the INIT or INIT ACK chunk, a
823 * number of data elements needs to be maintained including:
824 */
825 /* RTO : The current retransmission timeout value. */
826 unsigned long rto;
827
828 __u32 rtt; /* This is the most recent RTT. */
829
830 /* RTTVAR : The current RTT variation. */
831 __u32 rttvar;
832
833 /* SRTT : The current smoothed round trip time. */
834 __u32 srtt;
835
836 /*
837 * These are the congestion stats.
838 */
839 /* cwnd : The current congestion window. */
840 __u32 cwnd; /* This is the actual cwnd. */
841
842 /* ssthresh : The current slow start threshold value. */
843 __u32 ssthresh;
844
845 /* partial : The tracking method for increase of cwnd when in
846 * bytes acked : congestion avoidance mode (see Section 6.2.2)
847 */
848 __u32 partial_bytes_acked;
849
850 /* Data that has been sent, but not acknowledged. */
851 __u32 flight_size;
852
853 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */
854
855 /* Destination */
856 struct dst_entry *dst;
857 /* Source address. */
858 union sctp_addr saddr;
859
860 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
861 * the destination address every heartbeat interval.
862 */
863 unsigned long hbinterval;
864 unsigned long probe_interval;
865
866 /* SACK delay timeout */
867 unsigned long sackdelay;
868 __u32 sackfreq;
869
870 atomic_t mtu_info;
871
872 /* When was the last time that we heard from this transport? We use
873 * this to pick new active and retran paths.
874 */
875 ktime_t last_time_heard;
876
877 /* When was the last time that we sent a chunk using this
878 * transport? We use this to check for idle transports
879 */
880 unsigned long last_time_sent;
881
882 /* Last time(in jiffies) when cwnd is reduced due to the congestion
883 * indication based on ECNE chunk.
884 */
885 unsigned long last_time_ecne_reduced;
886
887 __be16 encap_port;
888
889 /* This is the max_retrans value for the transport and will
890 * be initialized from the assocs value. This can be changed
891 * using the SCTP_SET_PEER_ADDR_PARAMS socket option.
892 */
893 __u16 pathmaxrxt;
894
895 __u32 flowlabel;
896 __u8 dscp;
897
898 /* This is the partially failed retrans value for the transport
899 * and will be initialized from the assocs value. This can be changed
900 * using the SCTP_PEER_ADDR_THLDS socket option
901 */
902 __u16 pf_retrans;
903 /* Used for primary path switchover. */
904 __u16 ps_retrans;
905 /* PMTU : The current known path MTU. */
906 __u32 pathmtu;
907
908 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
909 __u32 param_flags;
910
911 /* The number of times INIT has been sent on this transport. */
912 int init_sent_count;
913
914 /* state : The current state of this destination,
915 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
916 */
917 int state;
918
919 /* These are the error stats for this destination. */
920
921 /* Error count : The current error count for this destination. */
922 unsigned short error_count;
923
924 /* Per : A timer used by each destination.
925 * Destination :
926 * Timer :
927 *
928 * [Everywhere else in the text this is called T3-rtx. -ed]
929 */
930 struct timer_list T3_rtx_timer;
931
932 /* Heartbeat timer is per destination. */
933 struct timer_list hb_timer;
934
935 /* Timer to handle ICMP proto unreachable envets */
936 struct timer_list proto_unreach_timer;
937
938 /* Timer to handler reconf chunk rtx */
939 struct timer_list reconf_timer;
940
941 /* Timer to send a probe HB packet for PLPMTUD */
942 struct timer_list probe_timer;
943
944 /* Since we're using per-destination retransmission timers
945 * (see above), we're also using per-destination "transmitted"
946 * queues. This probably ought to be a private struct
947 * accessible only within the outqueue, but it's not, yet.
948 */
949 struct list_head transmitted;
950
951 /* We build bundle-able packets for this transport here. */
952 struct sctp_packet packet;
953
954 /* This is the list of transports that have chunks to send. */
955 struct list_head send_ready;
956
957 /* State information saved for SFR_CACC algorithm. The key
958 * idea in SFR_CACC is to maintain state at the sender on a
959 * per-destination basis when a changeover happens.
960 * char changeover_active;
961 * char cycling_changeover;
962 * __u32 next_tsn_at_change;
963 * char cacc_saw_newack;
964 */
965 struct {
966 /* An unsigned integer, which stores the next TSN to be
967 * used by the sender, at the moment of changeover.
968 */
969 __u32 next_tsn_at_change;
970
971 /* A flag which indicates the occurrence of a changeover */
972 char changeover_active;
973
974 /* A flag which indicates whether the change of primary is
975 * the first switch to this destination address during an
976 * active switch.
977 */
978 char cycling_changeover;
979
980 /* A temporary flag, which is used during the processing of
981 * a SACK to estimate the causative TSN(s)'s group.
982 */
983 char cacc_saw_newack;
984 } cacc;
985
986 struct {
987 __u32 last_rtx_chunks;
988 __u16 pmtu;
989 __u16 probe_size;
990 __u16 probe_high;
991 __u8 probe_count:3;
992 __u8 raise_count:5;
993 __u8 state;
994 } pl; /* plpmtud related */
995
996 /* 64-bit random number sent with heartbeat. */
997 __u64 hb_nonce;
998
999 struct rcu_head rcu;
1000 };
1001
1002 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *,
1003 gfp_t);
1004 void sctp_transport_set_owner(struct sctp_transport *,
1005 struct sctp_association *);
1006 void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
1007 struct sctp_sock *);
1008 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk);
1009 void sctp_transport_free(struct sctp_transport *);
1010 void sctp_transport_reset_t3_rtx(struct sctp_transport *);
1011 void sctp_transport_reset_hb_timer(struct sctp_transport *);
1012 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport);
1013 void sctp_transport_reset_probe_timer(struct sctp_transport *transport);
1014 int sctp_transport_hold(struct sctp_transport *);
1015 void sctp_transport_put(struct sctp_transport *);
1016 void sctp_transport_update_rto(struct sctp_transport *, __u32);
1017 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
1018 void sctp_transport_lower_cwnd(struct sctp_transport *t,
1019 enum sctp_lower_cwnd reason);
1020 void sctp_transport_burst_limited(struct sctp_transport *);
1021 void sctp_transport_burst_reset(struct sctp_transport *);
1022 unsigned long sctp_transport_timeout(struct sctp_transport *);
1023 void sctp_transport_reset(struct sctp_transport *t);
1024 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu);
1025 void sctp_transport_immediate_rtx(struct sctp_transport *);
1026 void sctp_transport_dst_release(struct sctp_transport *t);
1027 void sctp_transport_dst_confirm(struct sctp_transport *t);
1028 bool sctp_transport_pl_send(struct sctp_transport *t);
1029 bool sctp_transport_pl_recv(struct sctp_transport *t);
1030
1031
1032 /* This is the structure we use to queue packets as they come into
1033 * SCTP. We write packets to it and read chunks from it.
1034 */
1035 struct sctp_inq {
1036 /* This is actually a queue of sctp_chunk each
1037 * containing a partially decoded packet.
1038 */
1039 struct list_head in_chunk_list;
1040 /* This is the packet which is currently off the in queue and is
1041 * being worked on through the inbound chunk processing.
1042 */
1043 struct sctp_chunk *in_progress;
1044
1045 /* This is the delayed task to finish delivering inbound
1046 * messages.
1047 */
1048 struct work_struct immediate;
1049 };
1050
1051 void sctp_inq_init(struct sctp_inq *);
1052 void sctp_inq_free(struct sctp_inq *);
1053 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
1054 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
1055 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *);
1056 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t);
1057
1058 /* This is the structure we use to hold outbound chunks. You push
1059 * chunks in and they automatically pop out the other end as bundled
1060 * packets (it calls (*output_handler)()).
1061 *
1062 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1063 * and 8.2 of the v13 draft.
1064 *
1065 * It handles retransmissions. The connection to the timeout portion
1066 * of the state machine is through sctp_..._timeout() and timeout_handler.
1067 *
1068 * If you feed it SACKs, it will eat them.
1069 *
1070 * If you give it big chunks, it will fragment them.
1071 *
1072 * It assigns TSN's to data chunks. This happens at the last possible
1073 * instant before transmission.
1074 *
1075 * When free()'d, it empties itself out via output_handler().
1076 */
1077 struct sctp_outq {
1078 struct sctp_association *asoc;
1079
1080 /* Data pending that has never been transmitted. */
1081 struct list_head out_chunk_list;
1082
1083 /* Stream scheduler being used */
1084 struct sctp_sched_ops *sched;
1085
1086 unsigned int out_qlen; /* Total length of queued data chunks. */
1087
1088 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1089 unsigned int error;
1090
1091 /* These are control chunks we want to send. */
1092 struct list_head control_chunk_list;
1093
1094 /* These are chunks that have been sacked but are above the
1095 * CTSN, or cumulative tsn ack point.
1096 */
1097 struct list_head sacked;
1098
1099 /* Put chunks on this list to schedule them for
1100 * retransmission.
1101 */
1102 struct list_head retransmit;
1103
1104 /* Put chunks on this list to save them for FWD TSN processing as
1105 * they were abandoned.
1106 */
1107 struct list_head abandoned;
1108
1109 /* How many unackd bytes do we have in-flight? */
1110 __u32 outstanding_bytes;
1111
1112 /* Are we doing fast-rtx on this queue */
1113 char fast_rtx;
1114
1115 /* Corked? */
1116 char cork;
1117 };
1118
1119 void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1120 void sctp_outq_teardown(struct sctp_outq *);
1121 void sctp_outq_free(struct sctp_outq*);
1122 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t);
1123 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *);
1124 int sctp_outq_is_empty(const struct sctp_outq *);
1125 void sctp_outq_restart(struct sctp_outq *);
1126
1127 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport,
1128 enum sctp_retransmit_reason reason);
1129 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1130 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp);
1131 void sctp_prsctp_prune(struct sctp_association *asoc,
1132 struct sctp_sndrcvinfo *sinfo, int msg_len);
1133 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn);
1134 /* Uncork and flush an outqueue. */
sctp_outq_cork(struct sctp_outq * q)1135 static inline void sctp_outq_cork(struct sctp_outq *q)
1136 {
1137 q->cork = 1;
1138 }
1139
1140 /* SCTP skb control block.
1141 * sctp_input_cb is currently used on rx and sock rx queue
1142 */
1143 struct sctp_input_cb {
1144 union {
1145 struct inet_skb_parm h4;
1146 #if IS_ENABLED(CONFIG_IPV6)
1147 struct inet6_skb_parm h6;
1148 #endif
1149 } header;
1150 struct sctp_chunk *chunk;
1151 struct sctp_af *af;
1152 __be16 encap_port;
1153 };
1154 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0]))
1155
1156 struct sctp_output_cb {
1157 struct sk_buff *last;
1158 };
1159 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0]))
1160
sctp_gso_headskb(const struct sk_buff * skb)1161 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb)
1162 {
1163 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk;
1164
1165 return chunk->head_skb ? : skb;
1166 }
1167
1168 /* These bind address data fields common between endpoints and associations */
1169 struct sctp_bind_addr {
1170
1171 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1172 *
1173 * SCTP Port: The local SCTP port number the endpoint is
1174 * bound to.
1175 */
1176 __u16 port;
1177
1178 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1179 *
1180 * Address List: The list of IP addresses that this instance
1181 * has bound. This information is passed to one's
1182 * peer(s) in INIT and INIT ACK chunks.
1183 */
1184 struct list_head address_list;
1185 };
1186
1187 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1188 void sctp_bind_addr_free(struct sctp_bind_addr *);
1189 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest,
1190 const struct sctp_bind_addr *src,
1191 enum sctp_scope scope, gfp_t gfp,
1192 int flags);
1193 int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
1194 const struct sctp_bind_addr *src,
1195 gfp_t gfp);
1196 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1197 int new_size, __u8 addr_state, gfp_t gfp);
1198 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1199 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1200 struct sctp_sock *);
1201 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *,
1202 struct sctp_sock *, struct sctp_sock *);
1203 int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
1204 const union sctp_addr *addr);
1205 int sctp_bind_addrs_check(struct sctp_sock *sp,
1206 struct sctp_sock *sp2, int cnt2);
1207 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp,
1208 const union sctp_addr *addrs,
1209 int addrcnt,
1210 struct sctp_sock *opt);
1211 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1212 int *addrs_len,
1213 gfp_t gfp);
1214 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1215 __u16 port, gfp_t gfp);
1216
1217 enum sctp_scope sctp_scope(const union sctp_addr *addr);
1218 int sctp_in_scope(struct net *net, const union sctp_addr *addr,
1219 const enum sctp_scope scope);
1220 int sctp_is_any(struct sock *sk, const union sctp_addr *addr);
1221 int sctp_is_ep_boundall(struct sock *sk);
1222
1223
1224 /* What type of endpoint? */
1225 enum sctp_endpoint_type {
1226 SCTP_EP_TYPE_SOCKET,
1227 SCTP_EP_TYPE_ASSOCIATION,
1228 };
1229
1230 /*
1231 * A common base class to bridge the implmentation view of a
1232 * socket (usually listening) endpoint versus an association's
1233 * local endpoint.
1234 * This common structure is useful for several purposes:
1235 * 1) Common interface for lookup routines.
1236 * a) Subfunctions work for either endpoint or association
1237 * b) Single interface to lookup allows hiding the lookup lock rather
1238 * than acquiring it externally.
1239 * 2) Common interface for the inbound chunk handling/state machine.
1240 * 3) Common object handling routines for reference counting, etc.
1241 * 4) Disentangle association lookup from endpoint lookup, where we
1242 * do not have to find our endpoint to find our association.
1243 *
1244 */
1245
1246 struct sctp_ep_common {
1247 /* Fields to help us manage our entries in the hash tables. */
1248 struct hlist_node node;
1249 int hashent;
1250
1251 /* Runtime type information. What kind of endpoint is this? */
1252 enum sctp_endpoint_type type;
1253
1254 /* Some fields to help us manage this object.
1255 * refcnt - Reference count access to this object.
1256 * dead - Do not attempt to use this object.
1257 */
1258 refcount_t refcnt;
1259 bool dead;
1260
1261 /* What socket does this endpoint belong to? */
1262 struct sock *sk;
1263
1264 /* Cache netns and it won't change once set */
1265 struct net *net;
1266
1267 /* This is where we receive inbound chunks. */
1268 struct sctp_inq inqueue;
1269
1270 /* This substructure includes the defining parameters of the
1271 * endpoint:
1272 * bind_addr.port is our shared port number.
1273 * bind_addr.address_list is our set of local IP addresses.
1274 */
1275 struct sctp_bind_addr bind_addr;
1276 };
1277
1278
1279 /* RFC Section 1.4 Key Terms
1280 *
1281 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1282 * multi-homed host, an SCTP endpoint is represented to its peers as a
1283 * combination of a set of eligible destination transport addresses to
1284 * which SCTP packets can be sent and a set of eligible source
1285 * transport addresses from which SCTP packets can be received.
1286 * All transport addresses used by an SCTP endpoint must use the
1287 * same port number, but can use multiple IP addresses. A transport
1288 * address used by an SCTP endpoint must not be used by another
1289 * SCTP endpoint. In other words, a transport address is unique
1290 * to an SCTP endpoint.
1291 *
1292 * From an implementation perspective, each socket has one of these.
1293 * A TCP-style socket will have exactly one association on one of
1294 * these. An UDP-style socket will have multiple associations hanging
1295 * off one of these.
1296 */
1297
1298 struct sctp_endpoint {
1299 /* Common substructure for endpoint and association. */
1300 struct sctp_ep_common base;
1301
1302 /* Associations: A list of current associations and mappings
1303 * to the data consumers for each association. This
1304 * may be in the form of a hash table or other
1305 * implementation dependent structure. The data
1306 * consumers may be process identification
1307 * information such as file descriptors, named pipe
1308 * pointer, or table pointers dependent on how SCTP
1309 * is implemented.
1310 */
1311 /* This is really a list of struct sctp_association entries. */
1312 struct list_head asocs;
1313
1314 /* Secret Key: A secret key used by this endpoint to compute
1315 * the MAC. This SHOULD be a cryptographic quality
1316 * random number with a sufficient length.
1317 * Discussion in [RFC1750] can be helpful in
1318 * selection of the key.
1319 */
1320 __u8 secret_key[SCTP_SECRET_SIZE];
1321
1322 /* digest: This is a digest of the sctp cookie. This field is
1323 * only used on the receive path when we try to validate
1324 * that the cookie has not been tampered with. We put
1325 * this here so we pre-allocate this once and can re-use
1326 * on every receive.
1327 */
1328 __u8 *digest;
1329
1330 /* sendbuf acct. policy. */
1331 __u32 sndbuf_policy;
1332
1333 /* rcvbuf acct. policy. */
1334 __u32 rcvbuf_policy;
1335
1336 /* SCTP AUTH: array of the HMACs that will be allocated
1337 * we need this per association so that we don't serialize
1338 */
1339 struct crypto_shash **auth_hmacs;
1340
1341 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1342 struct sctp_hmac_algo_param *auth_hmacs_list;
1343
1344 /* SCTP-AUTH: chunks to authenticate encoded into parameter */
1345 struct sctp_chunks_param *auth_chunk_list;
1346
1347 /* SCTP-AUTH: endpoint shared keys */
1348 struct list_head endpoint_shared_keys;
1349 __u16 active_key_id;
1350 __u8 ecn_enable:1,
1351 auth_enable:1,
1352 intl_enable:1,
1353 prsctp_enable:1,
1354 asconf_enable:1,
1355 reconf_enable:1;
1356
1357 __u8 strreset_enable;
1358
1359 /* Security identifiers from incoming (INIT). These are set by
1360 * security_sctp_assoc_request(). These will only be used by
1361 * SCTP TCP type sockets and peeled off connections as they
1362 * cause a new socket to be generated. security_sctp_sk_clone()
1363 * will then plug these into the new socket.
1364 */
1365
1366 u32 secid;
1367 u32 peer_secid;
1368 };
1369
1370 /* Recover the outter endpoint structure. */
sctp_ep(struct sctp_ep_common * base)1371 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1372 {
1373 struct sctp_endpoint *ep;
1374
1375 ep = container_of(base, struct sctp_endpoint, base);
1376 return ep;
1377 }
1378
1379 /* These are function signatures for manipulating endpoints. */
1380 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1381 void sctp_endpoint_free(struct sctp_endpoint *);
1382 void sctp_endpoint_put(struct sctp_endpoint *);
1383 void sctp_endpoint_hold(struct sctp_endpoint *);
1384 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1385 struct sctp_association *sctp_endpoint_lookup_assoc(
1386 const struct sctp_endpoint *ep,
1387 const union sctp_addr *paddr,
1388 struct sctp_transport **);
1389 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep,
1390 const union sctp_addr *paddr);
1391 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1392 struct net *, const union sctp_addr *);
1393 bool sctp_has_association(struct net *net, const union sctp_addr *laddr,
1394 const union sctp_addr *paddr);
1395
1396 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep,
1397 const struct sctp_association *asoc,
1398 enum sctp_cid cid, struct sctp_init_chunk *peer_init,
1399 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk);
1400 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk,
1401 const union sctp_addr *peer,
1402 struct sctp_init_chunk *init, gfp_t gfp);
1403 __u32 sctp_generate_tag(const struct sctp_endpoint *);
1404 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
1405
1406 struct sctp_inithdr_host {
1407 __u32 init_tag;
1408 __u32 a_rwnd;
1409 __u16 num_outbound_streams;
1410 __u16 num_inbound_streams;
1411 __u32 initial_tsn;
1412 };
1413
1414 struct sctp_stream_priorities {
1415 /* List of priorities scheduled */
1416 struct list_head prio_sched;
1417 /* List of streams scheduled */
1418 struct list_head active;
1419 /* The next stream in line */
1420 struct sctp_stream_out_ext *next;
1421 __u16 prio;
1422 };
1423
1424 struct sctp_stream_out_ext {
1425 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1];
1426 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1];
1427 struct list_head outq; /* chunks enqueued by this stream */
1428 union {
1429 struct {
1430 /* Scheduled streams list */
1431 struct list_head prio_list;
1432 struct sctp_stream_priorities *prio_head;
1433 };
1434 /* Fields used by RR scheduler */
1435 struct {
1436 struct list_head rr_list;
1437 };
1438 };
1439 };
1440
1441 struct sctp_stream_out {
1442 union {
1443 __u32 mid;
1444 __u16 ssn;
1445 };
1446 __u32 mid_uo;
1447 struct sctp_stream_out_ext *ext;
1448 __u8 state;
1449 };
1450
1451 struct sctp_stream_in {
1452 union {
1453 __u32 mid;
1454 __u16 ssn;
1455 };
1456 __u32 mid_uo;
1457 __u32 fsn;
1458 __u32 fsn_uo;
1459 char pd_mode;
1460 char pd_mode_uo;
1461 };
1462
1463 struct sctp_stream {
1464 GENRADIX(struct sctp_stream_out) out;
1465 GENRADIX(struct sctp_stream_in) in;
1466
1467 __u16 outcnt;
1468 __u16 incnt;
1469 /* Current stream being sent, if any */
1470 struct sctp_stream_out *out_curr;
1471 union {
1472 /* Fields used by priority scheduler */
1473 struct {
1474 /* List of priorities scheduled */
1475 struct list_head prio_list;
1476 };
1477 /* Fields used by RR scheduler */
1478 struct {
1479 /* List of streams scheduled */
1480 struct list_head rr_list;
1481 /* The next stream in line */
1482 struct sctp_stream_out_ext *rr_next;
1483 };
1484 };
1485 struct sctp_stream_interleave *si;
1486 };
1487
sctp_stream_out(struct sctp_stream * stream,__u16 sid)1488 static inline struct sctp_stream_out *sctp_stream_out(
1489 struct sctp_stream *stream,
1490 __u16 sid)
1491 {
1492 return genradix_ptr(&stream->out, sid);
1493 }
1494
sctp_stream_in(struct sctp_stream * stream,__u16 sid)1495 static inline struct sctp_stream_in *sctp_stream_in(
1496 struct sctp_stream *stream,
1497 __u16 sid)
1498 {
1499 return genradix_ptr(&stream->in, sid);
1500 }
1501
1502 #define SCTP_SO(s, i) sctp_stream_out((s), (i))
1503 #define SCTP_SI(s, i) sctp_stream_in((s), (i))
1504
1505 #define SCTP_STREAM_CLOSED 0x00
1506 #define SCTP_STREAM_OPEN 0x01
1507
sctp_datachk_len(const struct sctp_stream * stream)1508 static inline __u16 sctp_datachk_len(const struct sctp_stream *stream)
1509 {
1510 return stream->si->data_chunk_len;
1511 }
1512
sctp_datahdr_len(const struct sctp_stream * stream)1513 static inline __u16 sctp_datahdr_len(const struct sctp_stream *stream)
1514 {
1515 return stream->si->data_chunk_len - sizeof(struct sctp_chunkhdr);
1516 }
1517
sctp_ftsnchk_len(const struct sctp_stream * stream)1518 static inline __u16 sctp_ftsnchk_len(const struct sctp_stream *stream)
1519 {
1520 return stream->si->ftsn_chunk_len;
1521 }
1522
sctp_ftsnhdr_len(const struct sctp_stream * stream)1523 static inline __u16 sctp_ftsnhdr_len(const struct sctp_stream *stream)
1524 {
1525 return stream->si->ftsn_chunk_len - sizeof(struct sctp_chunkhdr);
1526 }
1527
1528 /* SCTP_GET_ASSOC_STATS counters */
1529 struct sctp_priv_assoc_stats {
1530 /* Maximum observed rto in the association during subsequent
1531 * observations. Value is set to 0 if no RTO measurement took place
1532 * The transport where the max_rto was observed is returned in
1533 * obs_rto_ipaddr
1534 */
1535 struct sockaddr_storage obs_rto_ipaddr;
1536 __u64 max_obs_rto;
1537 /* Total In and Out SACKs received and sent */
1538 __u64 isacks;
1539 __u64 osacks;
1540 /* Total In and Out packets received and sent */
1541 __u64 opackets;
1542 __u64 ipackets;
1543 /* Total retransmitted chunks */
1544 __u64 rtxchunks;
1545 /* TSN received > next expected */
1546 __u64 outofseqtsns;
1547 /* Duplicate Chunks received */
1548 __u64 idupchunks;
1549 /* Gap Ack Blocks received */
1550 __u64 gapcnt;
1551 /* Unordered data chunks sent and received */
1552 __u64 ouodchunks;
1553 __u64 iuodchunks;
1554 /* Ordered data chunks sent and received */
1555 __u64 oodchunks;
1556 __u64 iodchunks;
1557 /* Control chunks sent and received */
1558 __u64 octrlchunks;
1559 __u64 ictrlchunks;
1560 };
1561
1562 /* RFC2960
1563 *
1564 * 12. Recommended Transmission Control Block (TCB) Parameters
1565 *
1566 * This section details a recommended set of parameters that should
1567 * be contained within the TCB for an implementation. This section is
1568 * for illustrative purposes and should not be deemed as requirements
1569 * on an implementation or as an exhaustive list of all parameters
1570 * inside an SCTP TCB. Each implementation may need its own additional
1571 * parameters for optimization.
1572 */
1573
1574
1575 /* Here we have information about each individual association. */
1576 struct sctp_association {
1577
1578 /* A base structure common to endpoint and association.
1579 * In this context, it represents the associations's view
1580 * of the local endpoint of the association.
1581 */
1582 struct sctp_ep_common base;
1583
1584 /* Associations on the same socket. */
1585 struct list_head asocs;
1586
1587 /* association id. */
1588 sctp_assoc_t assoc_id;
1589
1590 /* This is our parent endpoint. */
1591 struct sctp_endpoint *ep;
1592
1593 /* These are those association elements needed in the cookie. */
1594 struct sctp_cookie c;
1595
1596 /* This is all information about our peer. */
1597 struct {
1598 /* transport_addr_list
1599 *
1600 * Peer : A list of SCTP transport addresses that the
1601 * Transport : peer is bound to. This information is derived
1602 * Address : from the INIT or INIT ACK and is used to
1603 * List : associate an inbound packet with a given
1604 * : association. Normally this information is
1605 * : hashed or keyed for quick lookup and access
1606 * : of the TCB.
1607 * : The list is also initialized with the list
1608 * : of addresses passed with the sctp_connectx()
1609 * : call.
1610 *
1611 * It is a list of SCTP_transport's.
1612 */
1613 struct list_head transport_addr_list;
1614
1615 /* rwnd
1616 *
1617 * Peer Rwnd : Current calculated value of the peer's rwnd.
1618 */
1619 __u32 rwnd;
1620
1621 /* transport_count
1622 *
1623 * Peer : A count of the number of peer addresses
1624 * Transport : in the Peer Transport Address List.
1625 * Address :
1626 * Count :
1627 */
1628 __u16 transport_count;
1629
1630 /* port
1631 * The transport layer port number.
1632 */
1633 __u16 port;
1634
1635 /* primary_path
1636 *
1637 * Primary : This is the current primary destination
1638 * Path : transport address of the peer endpoint. It
1639 * : may also specify a source transport address
1640 * : on this endpoint.
1641 *
1642 * All of these paths live on transport_addr_list.
1643 *
1644 * At the bakeoffs, we discovered that the intent of
1645 * primaryPath is that it only changes when the ULP
1646 * asks to have it changed. We add the activePath to
1647 * designate the connection we are currently using to
1648 * transmit new data and most control chunks.
1649 */
1650 struct sctp_transport *primary_path;
1651
1652 /* Cache the primary path address here, when we
1653 * need a an address for msg_name.
1654 */
1655 union sctp_addr primary_addr;
1656
1657 /* active_path
1658 * The path that we are currently using to
1659 * transmit new data and most control chunks.
1660 */
1661 struct sctp_transport *active_path;
1662
1663 /* retran_path
1664 *
1665 * RFC2960 6.4 Multi-homed SCTP Endpoints
1666 * ...
1667 * Furthermore, when its peer is multi-homed, an
1668 * endpoint SHOULD try to retransmit a chunk to an
1669 * active destination transport address that is
1670 * different from the last destination address to
1671 * which the DATA chunk was sent.
1672 */
1673 struct sctp_transport *retran_path;
1674
1675 /* Pointer to last transport I have sent on. */
1676 struct sctp_transport *last_sent_to;
1677
1678 /* This is the last transport I have received DATA on. */
1679 struct sctp_transport *last_data_from;
1680
1681 /*
1682 * Mapping An array of bits or bytes indicating which out of
1683 * Array order TSN's have been received (relative to the
1684 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1685 * order packets have been received, this array
1686 * will be set to all zero. This structure may be
1687 * in the form of a circular buffer or bit array.
1688 *
1689 * Last Rcvd : This is the last TSN received in
1690 * TSN : sequence. This value is set initially by
1691 * : taking the peer's Initial TSN, received in
1692 * : the INIT or INIT ACK chunk, and subtracting
1693 * : one from it.
1694 *
1695 * Throughout most of the specification this is called the
1696 * "Cumulative TSN ACK Point". In this case, we
1697 * ignore the advice in 12.2 in favour of the term
1698 * used in the bulk of the text. This value is hidden
1699 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1700 */
1701 struct sctp_tsnmap tsn_map;
1702
1703 /* This mask is used to disable sending the ASCONF chunk
1704 * with specified parameter to peer.
1705 */
1706 __be16 addip_disabled_mask;
1707
1708 /* These are capabilities which our peer advertised. */
1709 __u16 ecn_capable:1, /* Can peer do ECN? */
1710 ipv4_address:1, /* Peer understands IPv4 addresses? */
1711 ipv6_address:1, /* Peer understands IPv6 addresses? */
1712 hostname_address:1, /* Peer understands DNS addresses? */
1713 asconf_capable:1, /* Does peer support ADDIP? */
1714 prsctp_capable:1, /* Can peer do PR-SCTP? */
1715 reconf_capable:1, /* Can peer do RE-CONFIG? */
1716 intl_capable:1, /* Can peer do INTERLEAVE */
1717 auth_capable:1, /* Is peer doing SCTP-AUTH? */
1718 /* sack_needed:
1719 * This flag indicates if the next received
1720 * packet is to be responded to with a
1721 * SACK. This is initialized to 0. When a packet
1722 * is received sack_cnt is incremented. If this value
1723 * reaches 2 or more, a SACK is sent and the
1724 * value is reset to 0. Note: This is used only
1725 * when no DATA chunks are received out of
1726 * order. When DATA chunks are out of order,
1727 * SACK's are not delayed (see Section 6).
1728 */
1729 sack_needed:1, /* Do we need to sack the peer? */
1730 sack_generation:1,
1731 zero_window_announced:1;
1732
1733 __u32 sack_cnt;
1734
1735 __u32 adaptation_ind; /* Adaptation Code point. */
1736
1737 struct sctp_inithdr_host i;
1738 void *cookie;
1739 int cookie_len;
1740
1741 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1742 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1743 * Initial TSN Value minus 1
1744 */
1745 __u32 addip_serial;
1746
1747 /* SCTP-AUTH: We need to know pears random number, hmac list
1748 * and authenticated chunk list. All that is part of the
1749 * cookie and these are just pointers to those locations
1750 */
1751 struct sctp_random_param *peer_random;
1752 struct sctp_chunks_param *peer_chunks;
1753 struct sctp_hmac_algo_param *peer_hmacs;
1754 } peer;
1755
1756 /* State : A state variable indicating what state the
1757 * : association is in, i.e. COOKIE-WAIT,
1758 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1759 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1760 *
1761 * Note: No "CLOSED" state is illustrated since if a
1762 * association is "CLOSED" its TCB SHOULD be removed.
1763 *
1764 * In this implementation we DO have a CLOSED
1765 * state which is used during initiation and shutdown.
1766 *
1767 * State takes values from SCTP_STATE_*.
1768 */
1769 enum sctp_state state;
1770
1771 /* Overall : The overall association error count.
1772 * Error Count : [Clear this any time I get something.]
1773 */
1774 int overall_error_count;
1775
1776 /* The cookie life I award for any cookie. */
1777 ktime_t cookie_life;
1778
1779 /* These are the association's initial, max, and min RTO values.
1780 * These values will be initialized by system defaults, but can
1781 * be modified via the SCTP_RTOINFO socket option.
1782 */
1783 unsigned long rto_initial;
1784 unsigned long rto_max;
1785 unsigned long rto_min;
1786
1787 /* Maximum number of new data packets that can be sent in a burst. */
1788 int max_burst;
1789
1790 /* This is the max_retrans value for the association. This value will
1791 * be initialized from system defaults, but can be
1792 * modified by the SCTP_ASSOCINFO socket option.
1793 */
1794 int max_retrans;
1795
1796 /* This is the partially failed retrans value for the transport
1797 * and will be initialized from the assocs value. This can be
1798 * changed using the SCTP_PEER_ADDR_THLDS socket option
1799 */
1800 __u16 pf_retrans;
1801 /* Used for primary path switchover. */
1802 __u16 ps_retrans;
1803
1804 /* Maximum number of times the endpoint will retransmit INIT */
1805 __u16 max_init_attempts;
1806
1807 /* How many times have we resent an INIT? */
1808 __u16 init_retries;
1809
1810 /* The largest timeout or RTO value to use in attempting an INIT */
1811 unsigned long max_init_timeo;
1812
1813 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1814 * the destination address every heartbeat interval. This value
1815 * will be inherited by all new transports.
1816 */
1817 unsigned long hbinterval;
1818 unsigned long probe_interval;
1819
1820 __be16 encap_port;
1821
1822 /* This is the max_retrans value for new transports in the
1823 * association.
1824 */
1825 __u16 pathmaxrxt;
1826
1827 __u32 flowlabel;
1828 __u8 dscp;
1829
1830 /* Flag that path mtu update is pending */
1831 __u8 pmtu_pending;
1832
1833 /* Association : The smallest PMTU discovered for all of the
1834 * PMTU : peer's transport addresses.
1835 */
1836 __u32 pathmtu;
1837
1838 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1839 __u32 param_flags;
1840
1841 __u32 sackfreq;
1842 /* SACK delay timeout */
1843 unsigned long sackdelay;
1844
1845 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES];
1846 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1847
1848 /* Transport to which SHUTDOWN chunk was last sent. */
1849 struct sctp_transport *shutdown_last_sent_to;
1850
1851 /* Transport to which INIT chunk was last sent. */
1852 struct sctp_transport *init_last_sent_to;
1853
1854 /* How many times have we resent a SHUTDOWN */
1855 int shutdown_retries;
1856
1857 /* Next TSN : The next TSN number to be assigned to a new
1858 * : DATA chunk. This is sent in the INIT or INIT
1859 * : ACK chunk to the peer and incremented each
1860 * : time a DATA chunk is assigned a TSN
1861 * : (normally just prior to transmit or during
1862 * : fragmentation).
1863 */
1864 __u32 next_tsn;
1865
1866 /*
1867 * Last Rcvd : This is the last TSN received in sequence. This value
1868 * TSN : is set initially by taking the peer's Initial TSN,
1869 * : received in the INIT or INIT ACK chunk, and
1870 * : subtracting one from it.
1871 *
1872 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1873 */
1874
1875 __u32 ctsn_ack_point;
1876
1877 /* PR-SCTP Advanced.Peer.Ack.Point */
1878 __u32 adv_peer_ack_point;
1879
1880 /* Highest TSN that is acknowledged by incoming SACKs. */
1881 __u32 highest_sacked;
1882
1883 /* TSN marking the fast recovery exit point */
1884 __u32 fast_recovery_exit;
1885
1886 /* Flag to track the current fast recovery state */
1887 __u8 fast_recovery;
1888
1889 /* The number of unacknowledged data chunks. Reported through
1890 * the SCTP_STATUS sockopt.
1891 */
1892 __u16 unack_data;
1893
1894 /* The total number of data chunks that we've had to retransmit
1895 * as the result of a T3 timer expiration
1896 */
1897 __u32 rtx_data_chunks;
1898
1899 /* This is the association's receive buffer space. This value is used
1900 * to set a_rwnd field in an INIT or a SACK chunk.
1901 */
1902 __u32 rwnd;
1903
1904 /* This is the last advertised value of rwnd over a SACK chunk. */
1905 __u32 a_rwnd;
1906
1907 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1908 * to slop over a maximum of the association's frag_point.
1909 */
1910 __u32 rwnd_over;
1911
1912 /* Keeps treack of rwnd pressure. This happens when we have
1913 * a window, but not recevie buffer (i.e small packets). This one
1914 * is releases slowly (1 PMTU at a time ).
1915 */
1916 __u32 rwnd_press;
1917
1918 /* This is the sndbuf size in use for the association.
1919 * This corresponds to the sndbuf size for the association,
1920 * as specified in the sk->sndbuf.
1921 */
1922 int sndbuf_used;
1923
1924 /* This is the amount of memory that this association has allocated
1925 * in the receive path at any given time.
1926 */
1927 atomic_t rmem_alloc;
1928
1929 /* This is the wait queue head for send requests waiting on
1930 * the association sndbuf space.
1931 */
1932 wait_queue_head_t wait;
1933
1934 /* The message size at which SCTP fragmentation will occur. */
1935 __u32 frag_point;
1936 __u32 user_frag;
1937
1938 /* Counter used to count INIT errors. */
1939 int init_err_counter;
1940
1941 /* Count the number of INIT cycles (for doubling timeout). */
1942 int init_cycle;
1943
1944 /* Default send parameters. */
1945 __u16 default_stream;
1946 __u16 default_flags;
1947 __u32 default_ppid;
1948 __u32 default_context;
1949 __u32 default_timetolive;
1950
1951 /* Default receive parameters */
1952 __u32 default_rcv_context;
1953
1954 /* Stream arrays */
1955 struct sctp_stream stream;
1956
1957 /* All outbound chunks go through this structure. */
1958 struct sctp_outq outqueue;
1959
1960 /* A smart pipe that will handle reordering and fragmentation,
1961 * as well as handle passing events up to the ULP.
1962 */
1963 struct sctp_ulpq ulpq;
1964
1965 /* Last TSN that caused an ECNE Chunk to be sent. */
1966 __u32 last_ecne_tsn;
1967
1968 /* Last TSN that caused a CWR Chunk to be sent. */
1969 __u32 last_cwr_tsn;
1970
1971 /* How many duplicated TSNs have we seen? */
1972 int numduptsns;
1973
1974 /* These are to support
1975 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1976 * and Enforcement of Flow and Message Limits"
1977 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1978 * or "ADDIP" for short.
1979 */
1980
1981
1982
1983 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1984 *
1985 * R1) One and only one ASCONF Chunk MAY be in transit and
1986 * unacknowledged at any one time. If a sender, after sending
1987 * an ASCONF chunk, decides it needs to transfer another
1988 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1989 * returns from the previous ASCONF Chunk before sending a
1990 * subsequent ASCONF. Note this restriction binds each side,
1991 * so at any time two ASCONF may be in-transit on any given
1992 * association (one sent from each endpoint).
1993 *
1994 * [This is our one-and-only-one ASCONF in flight. If we do
1995 * not have an ASCONF in flight, this is NULL.]
1996 */
1997 struct sctp_chunk *addip_last_asconf;
1998
1999 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
2000 *
2001 * This is needed to implement itmes E1 - E4 of the updated
2002 * spec. Here is the justification:
2003 *
2004 * Since the peer may bundle multiple ASCONF chunks toward us,
2005 * we now need the ability to cache multiple ACKs. The section
2006 * describes in detail how they are cached and cleaned up.
2007 */
2008 struct list_head asconf_ack_list;
2009
2010 /* These ASCONF chunks are waiting to be sent.
2011 *
2012 * These chunaks can't be pushed to outqueue until receiving
2013 * ASCONF_ACK for the previous ASCONF indicated by
2014 * addip_last_asconf, so as to guarantee that only one ASCONF
2015 * is in flight at any time.
2016 *
2017 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
2018 *
2019 * In defining the ASCONF Chunk transfer procedures, it is
2020 * essential that these transfers MUST NOT cause congestion
2021 * within the network. To achieve this, we place these
2022 * restrictions on the transfer of ASCONF Chunks:
2023 *
2024 * R1) One and only one ASCONF Chunk MAY be in transit and
2025 * unacknowledged at any one time. If a sender, after sending
2026 * an ASCONF chunk, decides it needs to transfer another
2027 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
2028 * returns from the previous ASCONF Chunk before sending a
2029 * subsequent ASCONF. Note this restriction binds each side,
2030 * so at any time two ASCONF may be in-transit on any given
2031 * association (one sent from each endpoint).
2032 *
2033 *
2034 * [I really think this is EXACTLY the sort of intelligence
2035 * which already resides in sctp_outq. Please move this
2036 * queue and its supporting logic down there. --piggy]
2037 */
2038 struct list_head addip_chunk_list;
2039
2040 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2041 *
2042 * A2) A serial number should be assigned to the Chunk. The
2043 * serial number SHOULD be a monotonically increasing
2044 * number. The serial number SHOULD be initialized at
2045 * the start of the association to the same value as the
2046 * Initial TSN and every time a new ASCONF chunk is created
2047 * it is incremented by one after assigning the serial number
2048 * to the newly created chunk.
2049 *
2050 * ADDIP
2051 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
2052 *
2053 * Serial Number : 32 bits (unsigned integer)
2054 *
2055 * This value represents a Serial Number for the ASCONF
2056 * Chunk. The valid range of Serial Number is from 0 to
2057 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
2058 * after reaching 4294967295.
2059 */
2060 __u32 addip_serial;
2061 int src_out_of_asoc_ok;
2062 union sctp_addr *asconf_addr_del_pending;
2063 struct sctp_transport *new_transport;
2064
2065 /* SCTP AUTH: list of the endpoint shared keys. These
2066 * keys are provided out of band by the user applicaton
2067 * and can't change during the lifetime of the association
2068 */
2069 struct list_head endpoint_shared_keys;
2070
2071 /* SCTP AUTH:
2072 * The current generated assocaition shared key (secret)
2073 */
2074 struct sctp_auth_bytes *asoc_shared_key;
2075 struct sctp_shared_key *shkey;
2076
2077 /* SCTP AUTH: hmac id of the first peer requested algorithm
2078 * that we support.
2079 */
2080 __u16 default_hmac_id;
2081
2082 __u16 active_key_id;
2083
2084 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */
2085 temp:1, /* Is it a temporary association? */
2086 pf_expose:2, /* Expose pf state? */
2087 force_delay:1;
2088
2089 __u8 strreset_enable;
2090 __u8 strreset_outstanding; /* request param count on the fly */
2091
2092 __u32 strreset_outseq; /* Update after receiving response */
2093 __u32 strreset_inseq; /* Update after receiving request */
2094 __u32 strreset_result[2]; /* save the results of last 2 responses */
2095
2096 struct sctp_chunk *strreset_chunk; /* save request chunk */
2097
2098 struct sctp_priv_assoc_stats stats;
2099
2100 int sent_cnt_removable;
2101
2102 __u16 subscribe;
2103
2104 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1];
2105 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1];
2106
2107 struct rcu_head rcu;
2108 };
2109
2110
2111 /* An eyecatcher for determining if we are really looking at an
2112 * association data structure.
2113 */
2114 enum {
2115 SCTP_ASSOC_EYECATCHER = 0xa550c123,
2116 };
2117
2118 /* Recover the outter association structure. */
sctp_assoc(struct sctp_ep_common * base)2119 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
2120 {
2121 struct sctp_association *asoc;
2122
2123 asoc = container_of(base, struct sctp_association, base);
2124 return asoc;
2125 }
2126
2127 /* These are function signatures for manipulating associations. */
2128
2129
2130 struct sctp_association *
2131 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk,
2132 enum sctp_scope scope, gfp_t gfp);
2133 void sctp_association_free(struct sctp_association *);
2134 void sctp_association_put(struct sctp_association *);
2135 void sctp_association_hold(struct sctp_association *);
2136
2137 struct sctp_transport *sctp_assoc_choose_alter_transport(
2138 struct sctp_association *, struct sctp_transport *);
2139 void sctp_assoc_update_retran_path(struct sctp_association *);
2140 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
2141 const union sctp_addr *);
2142 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
2143 const union sctp_addr *laddr);
2144 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
2145 const union sctp_addr *address,
2146 const gfp_t gfp,
2147 const int peer_state);
2148 void sctp_assoc_del_peer(struct sctp_association *asoc,
2149 const union sctp_addr *addr);
2150 void sctp_assoc_rm_peer(struct sctp_association *asoc,
2151 struct sctp_transport *peer);
2152 void sctp_assoc_control_transport(struct sctp_association *asoc,
2153 struct sctp_transport *transport,
2154 enum sctp_transport_cmd command,
2155 sctp_sn_error_t error);
2156 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
2157 void sctp_assoc_migrate(struct sctp_association *, struct sock *);
2158 int sctp_assoc_update(struct sctp_association *old,
2159 struct sctp_association *new);
2160
2161 __u32 sctp_association_get_next_tsn(struct sctp_association *);
2162
2163 void sctp_assoc_update_frag_point(struct sctp_association *asoc);
2164 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu);
2165 void sctp_assoc_sync_pmtu(struct sctp_association *asoc);
2166 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int);
2167 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int);
2168 void sctp_assoc_set_primary(struct sctp_association *,
2169 struct sctp_transport *);
2170 void sctp_assoc_del_nonprimary_peers(struct sctp_association *,
2171 struct sctp_transport *);
2172 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc,
2173 enum sctp_scope scope, gfp_t gfp);
2174 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
2175 struct sctp_cookie*,
2176 gfp_t gfp);
2177 int sctp_assoc_set_id(struct sctp_association *, gfp_t);
2178 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc);
2179 struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
2180 const struct sctp_association *asoc,
2181 __be32 serial);
2182 void sctp_asconf_queue_teardown(struct sctp_association *asoc);
2183
2184 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
2185 const union sctp_addr *ss2);
2186 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
2187
2188 /* A convenience structure to parse out SCTP specific CMSGs. */
2189 struct sctp_cmsgs {
2190 struct sctp_initmsg *init;
2191 struct sctp_sndrcvinfo *srinfo;
2192 struct sctp_sndinfo *sinfo;
2193 struct sctp_prinfo *prinfo;
2194 struct sctp_authinfo *authinfo;
2195 struct msghdr *addrs_msg;
2196 };
2197
2198 /* Structure for tracking memory objects */
2199 struct sctp_dbg_objcnt_entry {
2200 char *label;
2201 atomic_t *counter;
2202 };
2203
2204 #endif /* __sctp_structs_h__ */
2205
