1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* SCTP kernel implementation
3 * (C) Copyright IBM Corp. 2001, 2004
4 * Copyright (c) 1999-2000 Cisco, Inc.
5 * Copyright (c) 1999-2001 Motorola, Inc.
6 * Copyright (c) 2001 Intel Corp.
7 *
8 * This file is part of the SCTP kernel implementation
9 *
10 * Please send any bug reports or fixes you make to the
11 * email addresses:
12 * lksctp developers <linux-sctp@vger.kernel.org>
13 *
14 * Written or modified by:
15 * Randall Stewart <randall@sctp.chicago.il.us>
16 * Ken Morneau <kmorneau@cisco.com>
17 * Qiaobing Xie <qxie1@email.mot.com>
18 * La Monte H.P. Yarroll <piggy@acm.org>
19 * Karl Knutson <karl@athena.chicago.il.us>
20 * Jon Grimm <jgrimm@us.ibm.com>
21 * Xingang Guo <xingang.guo@intel.com>
22 * Hui Huang <hui.huang@nokia.com>
23 * Sridhar Samudrala <sri@us.ibm.com>
24 * Daisy Chang <daisyc@us.ibm.com>
25 * Dajiang Zhang <dajiang.zhang@nokia.com>
26 * Ardelle Fan <ardelle.fan@intel.com>
27 * Ryan Layer <rmlayer@us.ibm.com>
28 * Anup Pemmaiah <pemmaiah@cc.usu.edu>
29 * Kevin Gao <kevin.gao@intel.com>
30 */
31
32 #ifndef __sctp_structs_h__
33 #define __sctp_structs_h__
34
35 #include <linux/ktime.h>
36 #include <linux/generic-radix-tree.h>
37 #include <linux/rhashtable-types.h>
38 #include <linux/socket.h> /* linux/in.h needs this!! */
39 #include <linux/in.h> /* We get struct sockaddr_in. */
40 #include <linux/in6.h> /* We get struct in6_addr */
41 #include <linux/ipv6.h>
42 #include <asm/param.h> /* We get MAXHOSTNAMELEN. */
43 #include <linux/atomic.h> /* This gets us atomic counters. */
44 #include <linux/skbuff.h> /* We need sk_buff_head. */
45 #include <linux/workqueue.h> /* We need tq_struct. */
46 #include <linux/sctp.h> /* We need sctp* header structs. */
47 #include <net/sctp/auth.h> /* We need auth specific structs */
48 #include <net/ip.h> /* For inet_skb_parm */
49
50 /* A convenience structure for handling sockaddr structures.
51 * We should wean ourselves off this.
52 */
53 union sctp_addr {
54 struct sockaddr_in v4;
55 struct sockaddr_in6 v6;
56 struct sockaddr sa;
57 };
58
59 /* Forward declarations for data structures. */
60 struct sctp_globals;
61 struct sctp_endpoint;
62 struct sctp_association;
63 struct sctp_transport;
64 struct sctp_packet;
65 struct sctp_chunk;
66 struct sctp_inq;
67 struct sctp_outq;
68 struct sctp_bind_addr;
69 struct sctp_ulpq;
70 struct sctp_ep_common;
71 struct crypto_shash;
72 struct sctp_stream;
73
74
75 #include <net/sctp/tsnmap.h>
76 #include <net/sctp/ulpevent.h>
77 #include <net/sctp/ulpqueue.h>
78 #include <net/sctp/stream_interleave.h>
79
80 /* Structures useful for managing bind/connect. */
81
82 struct sctp_bind_bucket {
83 unsigned short port;
84 signed char fastreuse;
85 signed char fastreuseport;
86 kuid_t fastuid;
87 struct hlist_node node;
88 struct hlist_head owner;
89 struct net *net;
90 };
91
92 struct sctp_bind_hashbucket {
93 spinlock_t lock;
94 struct hlist_head chain;
95 };
96
97 /* Used for hashing all associations. */
98 struct sctp_hashbucket {
99 rwlock_t lock;
100 struct hlist_head chain;
101 } __attribute__((__aligned__(8)));
102
103
104 /* The SCTP globals structure. */
105 extern struct sctp_globals {
106 /* This is a list of groups of functions for each address
107 * family that we support.
108 */
109 struct list_head address_families;
110
111 /* This is the hash of all endpoints. */
112 struct sctp_hashbucket *ep_hashtable;
113 /* This is the sctp port control hash. */
114 struct sctp_bind_hashbucket *port_hashtable;
115 /* This is the hash of all transports. */
116 struct rhltable transport_hashtable;
117
118 /* Sizes of above hashtables. */
119 int ep_hashsize;
120 int port_hashsize;
121
122 /* Default initialization values to be applied to new associations. */
123 __u16 max_instreams;
124 __u16 max_outstreams;
125
126 /* Flag to indicate whether computing and verifying checksum
127 * is disabled. */
128 bool checksum_disable;
129 } sctp_globals;
130
131 #define sctp_max_instreams (sctp_globals.max_instreams)
132 #define sctp_max_outstreams (sctp_globals.max_outstreams)
133 #define sctp_address_families (sctp_globals.address_families)
134 #define sctp_ep_hashsize (sctp_globals.ep_hashsize)
135 #define sctp_ep_hashtable (sctp_globals.ep_hashtable)
136 #define sctp_port_hashsize (sctp_globals.port_hashsize)
137 #define sctp_port_hashtable (sctp_globals.port_hashtable)
138 #define sctp_transport_hashtable (sctp_globals.transport_hashtable)
139 #define sctp_checksum_disable (sctp_globals.checksum_disable)
140
141 /* SCTP Socket type: UDP or TCP style. */
142 enum sctp_socket_type {
143 SCTP_SOCKET_UDP = 0,
144 SCTP_SOCKET_UDP_HIGH_BANDWIDTH,
145 SCTP_SOCKET_TCP
146 };
147
148 /* Per socket SCTP information. */
149 struct sctp_sock {
150 /* inet_sock has to be the first member of sctp_sock */
151 struct inet_sock inet;
152 /* What kind of a socket is this? */
153 enum sctp_socket_type type;
154
155 /* PF_ family specific functions. */
156 struct sctp_pf *pf;
157
158 /* Access to HMAC transform. */
159 struct crypto_shash *hmac;
160 char *sctp_hmac_alg;
161
162 /* What is our base endpointer? */
163 struct sctp_endpoint *ep;
164
165 struct sctp_bind_bucket *bind_hash;
166 /* Various Socket Options. */
167 __u16 default_stream;
168 __u32 default_ppid;
169 __u16 default_flags;
170 __u32 default_context;
171 __u32 default_timetolive;
172 __u32 default_rcv_context;
173 int max_burst;
174
175 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
176 * the destination address every heartbeat interval. This value
177 * will be inherited by all new associations.
178 */
179 __u32 hbinterval;
180
181 /* This is the max_retrans value for new associations. */
182 __u16 pathmaxrxt;
183
184 __u32 flowlabel;
185 __u8 dscp;
186
187 __u16 pf_retrans;
188 __u16 ps_retrans;
189
190 /* The initial Path MTU to use for new associations. */
191 __u32 pathmtu;
192
193 /* The default SACK delay timeout for new associations. */
194 __u32 sackdelay;
195 __u32 sackfreq;
196
197 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
198 __u32 param_flags;
199
200 __u32 default_ss;
201
202 struct sctp_rtoinfo rtoinfo;
203 struct sctp_paddrparams paddrparam;
204 struct sctp_assocparams assocparams;
205
206 /*
207 * These two structures must be grouped together for the usercopy
208 * whitelist region.
209 */
210 __u16 subscribe;
211 struct sctp_initmsg initmsg;
212
213 int user_frag;
214
215 __u32 autoclose;
216 __u32 adaptation_ind;
217 __u32 pd_point;
218 __u16 nodelay:1,
219 pf_expose:2,
220 reuse:1,
221 disable_fragments:1,
222 v4mapped:1,
223 frag_interleave:1,
224 recvrcvinfo:1,
225 recvnxtinfo:1,
226 data_ready_signalled:1;
227
228 atomic_t pd_mode;
229
230 /* Fields after this point will be skipped on copies, like on accept
231 * and peeloff operations
232 */
233
234 /* Receive to here while partial delivery is in effect. */
235 struct sk_buff_head pd_lobby;
236
237 struct list_head auto_asconf_list;
238 int do_auto_asconf;
239 };
240
sctp_sk(const struct sock * sk)241 static inline struct sctp_sock *sctp_sk(const struct sock *sk)
242 {
243 return (struct sctp_sock *)sk;
244 }
245
sctp_opt2sk(const struct sctp_sock * sp)246 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp)
247 {
248 return (struct sock *)sp;
249 }
250
251 #if IS_ENABLED(CONFIG_IPV6)
252 struct sctp6_sock {
253 struct sctp_sock sctp;
254 struct ipv6_pinfo inet6;
255 };
256 #endif /* CONFIG_IPV6 */
257
258
259 /* This is our APPLICATION-SPECIFIC state cookie.
260 * THIS IS NOT DICTATED BY THE SPECIFICATION.
261 */
262 /* These are the parts of an association which we send in the cookie.
263 * Most of these are straight out of:
264 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB)
265 *
266 */
267
268 struct sctp_cookie {
269
270 /* My : Tag expected in every inbound packet and sent
271 * Verification: in the INIT or INIT ACK chunk.
272 * Tag :
273 */
274 __u32 my_vtag;
275
276 /* Peer's : Tag expected in every outbound packet except
277 * Verification: in the INIT chunk.
278 * Tag :
279 */
280 __u32 peer_vtag;
281
282 /* The rest of these are not from the spec, but really need to
283 * be in the cookie.
284 */
285
286 /* My Tie Tag : Assist in discovering a restarting association. */
287 __u32 my_ttag;
288
289 /* Peer's Tie Tag: Assist in discovering a restarting association. */
290 __u32 peer_ttag;
291
292 /* When does this cookie expire? */
293 ktime_t expiration;
294
295 /* Number of inbound/outbound streams which are set
296 * and negotiated during the INIT process.
297 */
298 __u16 sinit_num_ostreams;
299 __u16 sinit_max_instreams;
300
301 /* This is the first sequence number I used. */
302 __u32 initial_tsn;
303
304 /* This holds the originating address of the INIT packet. */
305 union sctp_addr peer_addr;
306
307 /* IG Section 2.35.3
308 * Include the source port of the INIT-ACK
309 */
310 __u16 my_port;
311
312 __u8 prsctp_capable;
313
314 /* Padding for future use */
315 __u8 padding;
316
317 __u32 adaptation_ind;
318
319 __u8 auth_random[sizeof(struct sctp_paramhdr) +
320 SCTP_AUTH_RANDOM_LENGTH];
321 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2];
322 __u8 auth_chunks[sizeof(struct sctp_paramhdr) + SCTP_AUTH_MAX_CHUNKS];
323
324 /* This is a shim for my peer's INIT packet, followed by
325 * a copy of the raw address list of the association.
326 * The length of the raw address list is saved in the
327 * raw_addr_list_len field, which will be used at the time when
328 * the association TCB is re-constructed from the cookie.
329 */
330 __u32 raw_addr_list_len;
331 struct sctp_init_chunk peer_init[];
332 };
333
334
335 /* The format of our cookie that we send to our peer. */
336 struct sctp_signed_cookie {
337 __u8 signature[SCTP_SECRET_SIZE];
338 __u32 __pad; /* force sctp_cookie alignment to 64 bits */
339 struct sctp_cookie c;
340 } __packed;
341
342 /* This is another convenience type to allocate memory for address
343 * params for the maximum size and pass such structures around
344 * internally.
345 */
346 union sctp_addr_param {
347 struct sctp_paramhdr p;
348 struct sctp_ipv4addr_param v4;
349 struct sctp_ipv6addr_param v6;
350 };
351
352 /* A convenience type to allow walking through the various
353 * parameters and avoid casting all over the place.
354 */
355 union sctp_params {
356 void *v;
357 struct sctp_paramhdr *p;
358 struct sctp_cookie_preserve_param *life;
359 struct sctp_hostname_param *dns;
360 struct sctp_cookie_param *cookie;
361 struct sctp_supported_addrs_param *sat;
362 struct sctp_ipv4addr_param *v4;
363 struct sctp_ipv6addr_param *v6;
364 union sctp_addr_param *addr;
365 struct sctp_adaptation_ind_param *aind;
366 struct sctp_supported_ext_param *ext;
367 struct sctp_random_param *random;
368 struct sctp_chunks_param *chunks;
369 struct sctp_hmac_algo_param *hmac_algo;
370 struct sctp_addip_param *addip;
371 };
372
373 /* RFC 2960. Section 3.3.5 Heartbeat.
374 * Heartbeat Information: variable length
375 * The Sender-specific Heartbeat Info field should normally include
376 * information about the sender's current time when this HEARTBEAT
377 * chunk is sent and the destination transport address to which this
378 * HEARTBEAT is sent (see Section 8.3).
379 */
380 struct sctp_sender_hb_info {
381 struct sctp_paramhdr param_hdr;
382 union sctp_addr daddr;
383 unsigned long sent_at;
384 __u64 hb_nonce;
385 };
386
387 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt,
388 gfp_t gfp);
389 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid);
390 void sctp_stream_free(struct sctp_stream *stream);
391 void sctp_stream_clear(struct sctp_stream *stream);
392 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new);
393
394 /* What is the current SSN number for this stream? */
395 #define sctp_ssn_peek(stream, type, sid) \
396 (sctp_stream_##type((stream), (sid))->ssn)
397
398 /* Return the next SSN number for this stream. */
399 #define sctp_ssn_next(stream, type, sid) \
400 (sctp_stream_##type((stream), (sid))->ssn++)
401
402 /* Skip over this ssn and all below. */
403 #define sctp_ssn_skip(stream, type, sid, ssn) \
404 (sctp_stream_##type((stream), (sid))->ssn = ssn + 1)
405
406 /* What is the current MID number for this stream? */
407 #define sctp_mid_peek(stream, type, sid) \
408 (sctp_stream_##type((stream), (sid))->mid)
409
410 /* Return the next MID number for this stream. */
411 #define sctp_mid_next(stream, type, sid) \
412 (sctp_stream_##type((stream), (sid))->mid++)
413
414 /* Skip over this mid and all below. */
415 #define sctp_mid_skip(stream, type, sid, mid) \
416 (sctp_stream_##type((stream), (sid))->mid = mid + 1)
417
418 /* What is the current MID_uo number for this stream? */
419 #define sctp_mid_uo_peek(stream, type, sid) \
420 (sctp_stream_##type((stream), (sid))->mid_uo)
421
422 /* Return the next MID_uo number for this stream. */
423 #define sctp_mid_uo_next(stream, type, sid) \
424 (sctp_stream_##type((stream), (sid))->mid_uo++)
425
426 /*
427 * Pointers to address related SCTP functions.
428 * (i.e. things that depend on the address family.)
429 */
430 struct sctp_af {
431 int (*sctp_xmit) (struct sk_buff *skb,
432 struct sctp_transport *);
433 int (*setsockopt) (struct sock *sk,
434 int level,
435 int optname,
436 sockptr_t optval,
437 unsigned int optlen);
438 int (*getsockopt) (struct sock *sk,
439 int level,
440 int optname,
441 char __user *optval,
442 int __user *optlen);
443 void (*get_dst) (struct sctp_transport *t,
444 union sctp_addr *saddr,
445 struct flowi *fl,
446 struct sock *sk);
447 void (*get_saddr) (struct sctp_sock *sk,
448 struct sctp_transport *t,
449 struct flowi *fl);
450 void (*copy_addrlist) (struct list_head *,
451 struct net_device *);
452 int (*cmp_addr) (const union sctp_addr *addr1,
453 const union sctp_addr *addr2);
454 void (*addr_copy) (union sctp_addr *dst,
455 union sctp_addr *src);
456 void (*from_skb) (union sctp_addr *,
457 struct sk_buff *skb,
458 int saddr);
459 void (*from_sk) (union sctp_addr *,
460 struct sock *sk);
461 void (*from_addr_param) (union sctp_addr *,
462 union sctp_addr_param *,
463 __be16 port, int iif);
464 int (*to_addr_param) (const union sctp_addr *,
465 union sctp_addr_param *);
466 int (*addr_valid) (union sctp_addr *,
467 struct sctp_sock *,
468 const struct sk_buff *);
469 enum sctp_scope (*scope)(union sctp_addr *);
470 void (*inaddr_any) (union sctp_addr *, __be16);
471 int (*is_any) (const union sctp_addr *);
472 int (*available) (union sctp_addr *,
473 struct sctp_sock *);
474 int (*skb_iif) (const struct sk_buff *sk);
475 int (*is_ce) (const struct sk_buff *sk);
476 void (*seq_dump_addr)(struct seq_file *seq,
477 union sctp_addr *addr);
478 void (*ecn_capable)(struct sock *sk);
479 __u16 net_header_len;
480 int sockaddr_len;
481 int (*ip_options_len)(struct sock *sk);
482 sa_family_t sa_family;
483 struct list_head list;
484 };
485
486 struct sctp_af *sctp_get_af_specific(sa_family_t);
487 int sctp_register_af(struct sctp_af *);
488
489 /* Protocol family functions. */
490 struct sctp_pf {
491 void (*event_msgname)(struct sctp_ulpevent *, char *, int *);
492 void (*skb_msgname) (struct sk_buff *, char *, int *);
493 int (*af_supported) (sa_family_t, struct sctp_sock *);
494 int (*cmp_addr) (const union sctp_addr *,
495 const union sctp_addr *,
496 struct sctp_sock *);
497 int (*bind_verify) (struct sctp_sock *, union sctp_addr *);
498 int (*send_verify) (struct sctp_sock *, union sctp_addr *);
499 int (*supported_addrs)(const struct sctp_sock *, __be16 *);
500 struct sock *(*create_accept_sk) (struct sock *sk,
501 struct sctp_association *asoc,
502 bool kern);
503 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr);
504 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk);
505 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk);
506 void (*copy_ip_options)(struct sock *sk, struct sock *newsk);
507 struct sctp_af *af;
508 };
509
510
511 /* Structure to track chunk fragments that have been acked, but peer
512 * fragments of the same message have not.
513 */
514 struct sctp_datamsg {
515 /* Chunks waiting to be submitted to lower layer. */
516 struct list_head chunks;
517 /* Reference counting. */
518 refcount_t refcnt;
519 /* When is this message no longer interesting to the peer? */
520 unsigned long expires_at;
521 /* Did the messenge fail to send? */
522 int send_error;
523 u8 send_failed:1,
524 can_delay:1, /* should this message be Nagle delayed */
525 abandoned:1; /* should this message be abandoned */
526 };
527
528 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *,
529 struct sctp_sndrcvinfo *,
530 struct iov_iter *);
531 void sctp_datamsg_free(struct sctp_datamsg *);
532 void sctp_datamsg_put(struct sctp_datamsg *);
533 void sctp_chunk_fail(struct sctp_chunk *, int error);
534 int sctp_chunk_abandoned(struct sctp_chunk *);
535
536 /* RFC2960 1.4 Key Terms
537 *
538 * o Chunk: A unit of information within an SCTP packet, consisting of
539 * a chunk header and chunk-specific content.
540 *
541 * As a matter of convenience, we remember the SCTP common header for
542 * each chunk as well as a few other header pointers...
543 */
544 struct sctp_chunk {
545 struct list_head list;
546
547 refcount_t refcnt;
548
549 /* How many times this chunk have been sent, for prsctp RTX policy */
550 int sent_count;
551
552 union {
553 /* This is our link to the per-transport transmitted list. */
554 struct list_head transmitted_list;
555 /* List in specific stream outq */
556 struct list_head stream_list;
557 };
558
559 /* This field is used by chunks that hold fragmented data.
560 * For the first fragment this is the list that holds the rest of
561 * fragments. For the remaining fragments, this is the link to the
562 * frag_list maintained in the first fragment.
563 */
564 struct list_head frag_list;
565
566 /* This points to the sk_buff containing the actual data. */
567 struct sk_buff *skb;
568
569 union {
570 /* In case of GSO packets, this will store the head one */
571 struct sk_buff *head_skb;
572 /* In case of auth enabled, this will point to the shkey */
573 struct sctp_shared_key *shkey;
574 };
575
576 /* These are the SCTP headers by reverse order in a packet.
577 * Note that some of these may happen more than once. In that
578 * case, we point at the "current" one, whatever that means
579 * for that level of header.
580 */
581
582 /* We point this at the FIRST TLV parameter to chunk_hdr. */
583 union sctp_params param_hdr;
584 union {
585 __u8 *v;
586 struct sctp_datahdr *data_hdr;
587 struct sctp_inithdr *init_hdr;
588 struct sctp_sackhdr *sack_hdr;
589 struct sctp_heartbeathdr *hb_hdr;
590 struct sctp_sender_hb_info *hbs_hdr;
591 struct sctp_shutdownhdr *shutdown_hdr;
592 struct sctp_signed_cookie *cookie_hdr;
593 struct sctp_ecnehdr *ecne_hdr;
594 struct sctp_cwrhdr *ecn_cwr_hdr;
595 struct sctp_errhdr *err_hdr;
596 struct sctp_addiphdr *addip_hdr;
597 struct sctp_fwdtsn_hdr *fwdtsn_hdr;
598 struct sctp_authhdr *auth_hdr;
599 struct sctp_idatahdr *idata_hdr;
600 struct sctp_ifwdtsn_hdr *ifwdtsn_hdr;
601 } subh;
602
603 __u8 *chunk_end;
604
605 struct sctp_chunkhdr *chunk_hdr;
606 struct sctphdr *sctp_hdr;
607
608 /* This needs to be recoverable for SCTP_SEND_FAILED events. */
609 struct sctp_sndrcvinfo sinfo;
610
611 /* Which association does this belong to? */
612 struct sctp_association *asoc;
613
614 /* What endpoint received this chunk? */
615 struct sctp_ep_common *rcvr;
616
617 /* We fill this in if we are calculating RTT. */
618 unsigned long sent_at;
619
620 /* What is the origin IP address for this chunk? */
621 union sctp_addr source;
622 /* Destination address for this chunk. */
623 union sctp_addr dest;
624
625 /* For outbound message, track all fragments for SEND_FAILED. */
626 struct sctp_datamsg *msg;
627
628 /* For an inbound chunk, this tells us where it came from.
629 * For an outbound chunk, it tells us where we'd like it to
630 * go. It is NULL if we have no preference.
631 */
632 struct sctp_transport *transport;
633
634 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO
635 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH
636 * spec violates the principle premis that all chunks are processed
637 * in order.
638 */
639 struct sk_buff *auth_chunk;
640
641 #define SCTP_CAN_FRTX 0x0
642 #define SCTP_NEED_FRTX 0x1
643 #define SCTP_DONT_FRTX 0x2
644 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */
645 has_tsn:1, /* Does this chunk have a TSN yet? */
646 has_ssn:1, /* Does this chunk have a SSN yet? */
647 #define has_mid has_ssn
648 singleton:1, /* Only chunk in the packet? */
649 end_of_packet:1, /* Last chunk in the packet? */
650 ecn_ce_done:1, /* Have we processed the ECN CE bit? */
651 pdiscard:1, /* Discard the whole packet now? */
652 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */
653 data_accepted:1, /* At least 1 chunk accepted */
654 auth:1, /* IN: was auth'ed | OUT: needs auth */
655 has_asconf:1, /* IN: have seen an asconf before */
656 tsn_missing_report:2, /* Data chunk missing counter. */
657 fast_retransmit:2; /* Is this chunk fast retransmitted? */
658 };
659
660 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1)
661 void sctp_chunk_hold(struct sctp_chunk *);
662 void sctp_chunk_put(struct sctp_chunk *);
663 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len,
664 struct iov_iter *from);
665 void sctp_chunk_free(struct sctp_chunk *);
666 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data);
667 struct sctp_chunk *sctp_chunkify(struct sk_buff *,
668 const struct sctp_association *,
669 struct sock *, gfp_t gfp);
670 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *,
671 union sctp_addr *);
672 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk);
673
sctp_chunk_stream_no(struct sctp_chunk * ch)674 static inline __u16 sctp_chunk_stream_no(struct sctp_chunk *ch)
675 {
676 return ntohs(ch->subh.data_hdr->stream);
677 }
678
679 enum {
680 SCTP_ADDR_NEW, /* new address added to assoc/ep */
681 SCTP_ADDR_SRC, /* address can be used as source */
682 SCTP_ADDR_DEL, /* address about to be deleted */
683 };
684
685 /* This is a structure for holding either an IPv6 or an IPv4 address. */
686 struct sctp_sockaddr_entry {
687 struct list_head list;
688 struct rcu_head rcu;
689 union sctp_addr a;
690 __u8 state;
691 __u8 valid;
692 };
693
694 #define SCTP_ADDRESS_TICK_DELAY 500
695
696 /* This structure holds lists of chunks as we are assembling for
697 * transmission.
698 */
699 struct sctp_packet {
700 /* These are the SCTP header values (host order) for the packet. */
701 __u16 source_port;
702 __u16 destination_port;
703 __u32 vtag;
704
705 /* This contains the payload chunks. */
706 struct list_head chunk_list;
707
708 /* This is the overhead of the sctp and ip headers. */
709 size_t overhead;
710 /* This is the total size of all chunks INCLUDING padding. */
711 size_t size;
712 /* This is the maximum size this packet may have */
713 size_t max_size;
714
715 /* The packet is destined for this transport address.
716 * The function we finally use to pass down to the next lower
717 * layer lives in the transport structure.
718 */
719 struct sctp_transport *transport;
720
721 /* pointer to the auth chunk for this packet */
722 struct sctp_chunk *auth;
723
724 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */
725 has_sack:1, /* This packet contains a SACK chunk. */
726 has_auth:1, /* This packet contains an AUTH chunk */
727 has_data:1, /* This packet contains at least 1 DATA chunk */
728 ipfragok:1; /* So let ip fragment this packet */
729 };
730
731 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *,
732 __u16 sport, __u16 dport);
733 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int);
734 enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet,
735 struct sctp_chunk *chunk,
736 int one_packet, gfp_t gfp);
737 enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet,
738 struct sctp_chunk *chunk);
739 int sctp_packet_transmit(struct sctp_packet *, gfp_t);
740 void sctp_packet_free(struct sctp_packet *);
741
sctp_packet_empty(struct sctp_packet * packet)742 static inline int sctp_packet_empty(struct sctp_packet *packet)
743 {
744 return packet->size == packet->overhead;
745 }
746
747 /* This represents a remote transport address.
748 * For local transport addresses, we just use union sctp_addr.
749 *
750 * RFC2960 Section 1.4 Key Terms
751 *
752 * o Transport address: A Transport Address is traditionally defined
753 * by Network Layer address, Transport Layer protocol and Transport
754 * Layer port number. In the case of SCTP running over IP, a
755 * transport address is defined by the combination of an IP address
756 * and an SCTP port number (where SCTP is the Transport protocol).
757 *
758 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control
759 *
760 * o The sender keeps a separate congestion control parameter set for
761 * each of the destination addresses it can send to (not each
762 * source-destination pair but for each destination). The parameters
763 * should decay if the address is not used for a long enough time
764 * period.
765 *
766 */
767 struct sctp_transport {
768 /* A list of transports. */
769 struct list_head transports;
770 struct rhlist_head node;
771
772 /* Reference counting. */
773 refcount_t refcnt;
774 /* RTO-Pending : A flag used to track if one of the DATA
775 * chunks sent to this address is currently being
776 * used to compute a RTT. If this flag is 0,
777 * the next DATA chunk sent to this destination
778 * should be used to compute a RTT and this flag
779 * should be set. Every time the RTT
780 * calculation completes (i.e. the DATA chunk
781 * is SACK'd) clear this flag.
782 */
783 __u32 rto_pending:1,
784
785 /*
786 * hb_sent : a flag that signals that we have a pending
787 * heartbeat.
788 */
789 hb_sent:1,
790
791 /* Is the Path MTU update pending on this tranport */
792 pmtu_pending:1,
793
794 dst_pending_confirm:1, /* need to confirm neighbour */
795
796 /* Has this transport moved the ctsn since we last sacked */
797 sack_generation:1;
798 u32 dst_cookie;
799
800 struct flowi fl;
801
802 /* This is the peer's IP address and port. */
803 union sctp_addr ipaddr;
804
805 /* These are the functions we call to handle LLP stuff. */
806 struct sctp_af *af_specific;
807
808 /* Which association do we belong to? */
809 struct sctp_association *asoc;
810
811 /* RFC2960
812 *
813 * 12.3 Per Transport Address Data
814 *
815 * For each destination transport address in the peer's
816 * address list derived from the INIT or INIT ACK chunk, a
817 * number of data elements needs to be maintained including:
818 */
819 /* RTO : The current retransmission timeout value. */
820 unsigned long rto;
821
822 __u32 rtt; /* This is the most recent RTT. */
823
824 /* RTTVAR : The current RTT variation. */
825 __u32 rttvar;
826
827 /* SRTT : The current smoothed round trip time. */
828 __u32 srtt;
829
830 /*
831 * These are the congestion stats.
832 */
833 /* cwnd : The current congestion window. */
834 __u32 cwnd; /* This is the actual cwnd. */
835
836 /* ssthresh : The current slow start threshold value. */
837 __u32 ssthresh;
838
839 /* partial : The tracking method for increase of cwnd when in
840 * bytes acked : congestion avoidance mode (see Section 6.2.2)
841 */
842 __u32 partial_bytes_acked;
843
844 /* Data that has been sent, but not acknowledged. */
845 __u32 flight_size;
846
847 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */
848
849 /* Destination */
850 struct dst_entry *dst;
851 /* Source address. */
852 union sctp_addr saddr;
853
854 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
855 * the destination address every heartbeat interval.
856 */
857 unsigned long hbinterval;
858
859 /* SACK delay timeout */
860 unsigned long sackdelay;
861 __u32 sackfreq;
862
863 atomic_t mtu_info;
864
865 /* When was the last time that we heard from this transport? We use
866 * this to pick new active and retran paths.
867 */
868 ktime_t last_time_heard;
869
870 /* When was the last time that we sent a chunk using this
871 * transport? We use this to check for idle transports
872 */
873 unsigned long last_time_sent;
874
875 /* Last time(in jiffies) when cwnd is reduced due to the congestion
876 * indication based on ECNE chunk.
877 */
878 unsigned long last_time_ecne_reduced;
879
880 /* This is the max_retrans value for the transport and will
881 * be initialized from the assocs value. This can be changed
882 * using the SCTP_SET_PEER_ADDR_PARAMS socket option.
883 */
884 __u16 pathmaxrxt;
885
886 __u32 flowlabel;
887 __u8 dscp;
888
889 /* This is the partially failed retrans value for the transport
890 * and will be initialized from the assocs value. This can be changed
891 * using the SCTP_PEER_ADDR_THLDS socket option
892 */
893 __u16 pf_retrans;
894 /* Used for primary path switchover. */
895 __u16 ps_retrans;
896 /* PMTU : The current known path MTU. */
897 __u32 pathmtu;
898
899 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
900 __u32 param_flags;
901
902 /* The number of times INIT has been sent on this transport. */
903 int init_sent_count;
904
905 /* state : The current state of this destination,
906 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN.
907 */
908 int state;
909
910 /* These are the error stats for this destination. */
911
912 /* Error count : The current error count for this destination. */
913 unsigned short error_count;
914
915 /* Per : A timer used by each destination.
916 * Destination :
917 * Timer :
918 *
919 * [Everywhere else in the text this is called T3-rtx. -ed]
920 */
921 struct timer_list T3_rtx_timer;
922
923 /* Heartbeat timer is per destination. */
924 struct timer_list hb_timer;
925
926 /* Timer to handle ICMP proto unreachable envets */
927 struct timer_list proto_unreach_timer;
928
929 /* Timer to handler reconf chunk rtx */
930 struct timer_list reconf_timer;
931
932 /* Since we're using per-destination retransmission timers
933 * (see above), we're also using per-destination "transmitted"
934 * queues. This probably ought to be a private struct
935 * accessible only within the outqueue, but it's not, yet.
936 */
937 struct list_head transmitted;
938
939 /* We build bundle-able packets for this transport here. */
940 struct sctp_packet packet;
941
942 /* This is the list of transports that have chunks to send. */
943 struct list_head send_ready;
944
945 /* State information saved for SFR_CACC algorithm. The key
946 * idea in SFR_CACC is to maintain state at the sender on a
947 * per-destination basis when a changeover happens.
948 * char changeover_active;
949 * char cycling_changeover;
950 * __u32 next_tsn_at_change;
951 * char cacc_saw_newack;
952 */
953 struct {
954 /* An unsigned integer, which stores the next TSN to be
955 * used by the sender, at the moment of changeover.
956 */
957 __u32 next_tsn_at_change;
958
959 /* A flag which indicates the occurrence of a changeover */
960 char changeover_active;
961
962 /* A flag which indicates whether the change of primary is
963 * the first switch to this destination address during an
964 * active switch.
965 */
966 char cycling_changeover;
967
968 /* A temporary flag, which is used during the processing of
969 * a SACK to estimate the causative TSN(s)'s group.
970 */
971 char cacc_saw_newack;
972 } cacc;
973
974 /* 64-bit random number sent with heartbeat. */
975 __u64 hb_nonce;
976
977 struct rcu_head rcu;
978 };
979
980 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *,
981 gfp_t);
982 void sctp_transport_set_owner(struct sctp_transport *,
983 struct sctp_association *);
984 void sctp_transport_route(struct sctp_transport *, union sctp_addr *,
985 struct sctp_sock *);
986 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk);
987 void sctp_transport_free(struct sctp_transport *);
988 void sctp_transport_reset_t3_rtx(struct sctp_transport *);
989 void sctp_transport_reset_hb_timer(struct sctp_transport *);
990 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport);
991 int sctp_transport_hold(struct sctp_transport *);
992 void sctp_transport_put(struct sctp_transport *);
993 void sctp_transport_update_rto(struct sctp_transport *, __u32);
994 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32);
995 void sctp_transport_lower_cwnd(struct sctp_transport *t,
996 enum sctp_lower_cwnd reason);
997 void sctp_transport_burst_limited(struct sctp_transport *);
998 void sctp_transport_burst_reset(struct sctp_transport *);
999 unsigned long sctp_transport_timeout(struct sctp_transport *);
1000 void sctp_transport_reset(struct sctp_transport *t);
1001 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu);
1002 void sctp_transport_immediate_rtx(struct sctp_transport *);
1003 void sctp_transport_dst_release(struct sctp_transport *t);
1004 void sctp_transport_dst_confirm(struct sctp_transport *t);
1005
1006
1007 /* This is the structure we use to queue packets as they come into
1008 * SCTP. We write packets to it and read chunks from it.
1009 */
1010 struct sctp_inq {
1011 /* This is actually a queue of sctp_chunk each
1012 * containing a partially decoded packet.
1013 */
1014 struct list_head in_chunk_list;
1015 /* This is the packet which is currently off the in queue and is
1016 * being worked on through the inbound chunk processing.
1017 */
1018 struct sctp_chunk *in_progress;
1019
1020 /* This is the delayed task to finish delivering inbound
1021 * messages.
1022 */
1023 struct work_struct immediate;
1024 };
1025
1026 void sctp_inq_init(struct sctp_inq *);
1027 void sctp_inq_free(struct sctp_inq *);
1028 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet);
1029 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *);
1030 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *);
1031 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t);
1032
1033 /* This is the structure we use to hold outbound chunks. You push
1034 * chunks in and they automatically pop out the other end as bundled
1035 * packets (it calls (*output_handler)()).
1036 *
1037 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1,
1038 * and 8.2 of the v13 draft.
1039 *
1040 * It handles retransmissions. The connection to the timeout portion
1041 * of the state machine is through sctp_..._timeout() and timeout_handler.
1042 *
1043 * If you feed it SACKs, it will eat them.
1044 *
1045 * If you give it big chunks, it will fragment them.
1046 *
1047 * It assigns TSN's to data chunks. This happens at the last possible
1048 * instant before transmission.
1049 *
1050 * When free()'d, it empties itself out via output_handler().
1051 */
1052 struct sctp_outq {
1053 struct sctp_association *asoc;
1054
1055 /* Data pending that has never been transmitted. */
1056 struct list_head out_chunk_list;
1057
1058 /* Stream scheduler being used */
1059 struct sctp_sched_ops *sched;
1060
1061 unsigned int out_qlen; /* Total length of queued data chunks. */
1062
1063 /* Error of send failed, may used in SCTP_SEND_FAILED event. */
1064 unsigned int error;
1065
1066 /* These are control chunks we want to send. */
1067 struct list_head control_chunk_list;
1068
1069 /* These are chunks that have been sacked but are above the
1070 * CTSN, or cumulative tsn ack point.
1071 */
1072 struct list_head sacked;
1073
1074 /* Put chunks on this list to schedule them for
1075 * retransmission.
1076 */
1077 struct list_head retransmit;
1078
1079 /* Put chunks on this list to save them for FWD TSN processing as
1080 * they were abandoned.
1081 */
1082 struct list_head abandoned;
1083
1084 /* How many unackd bytes do we have in-flight? */
1085 __u32 outstanding_bytes;
1086
1087 /* Are we doing fast-rtx on this queue */
1088 char fast_rtx;
1089
1090 /* Corked? */
1091 char cork;
1092 };
1093
1094 void sctp_outq_init(struct sctp_association *, struct sctp_outq *);
1095 void sctp_outq_teardown(struct sctp_outq *);
1096 void sctp_outq_free(struct sctp_outq*);
1097 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t);
1098 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *);
1099 int sctp_outq_is_empty(const struct sctp_outq *);
1100 void sctp_outq_restart(struct sctp_outq *);
1101
1102 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport,
1103 enum sctp_retransmit_reason reason);
1104 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8);
1105 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp);
1106 void sctp_prsctp_prune(struct sctp_association *asoc,
1107 struct sctp_sndrcvinfo *sinfo, int msg_len);
1108 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn);
1109 /* Uncork and flush an outqueue. */
sctp_outq_cork(struct sctp_outq * q)1110 static inline void sctp_outq_cork(struct sctp_outq *q)
1111 {
1112 q->cork = 1;
1113 }
1114
1115 /* SCTP skb control block.
1116 * sctp_input_cb is currently used on rx and sock rx queue
1117 */
1118 struct sctp_input_cb {
1119 union {
1120 struct inet_skb_parm h4;
1121 #if IS_ENABLED(CONFIG_IPV6)
1122 struct inet6_skb_parm h6;
1123 #endif
1124 } header;
1125 struct sctp_chunk *chunk;
1126 struct sctp_af *af;
1127 };
1128 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0]))
1129
1130 struct sctp_output_cb {
1131 struct sk_buff *last;
1132 };
1133 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0]))
1134
sctp_gso_headskb(const struct sk_buff * skb)1135 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb)
1136 {
1137 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk;
1138
1139 return chunk->head_skb ? : skb;
1140 }
1141
1142 /* These bind address data fields common between endpoints and associations */
1143 struct sctp_bind_addr {
1144
1145 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1146 *
1147 * SCTP Port: The local SCTP port number the endpoint is
1148 * bound to.
1149 */
1150 __u16 port;
1151
1152 /* RFC 2960 12.1 Parameters necessary for the SCTP instance
1153 *
1154 * Address List: The list of IP addresses that this instance
1155 * has bound. This information is passed to one's
1156 * peer(s) in INIT and INIT ACK chunks.
1157 */
1158 struct list_head address_list;
1159 };
1160
1161 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port);
1162 void sctp_bind_addr_free(struct sctp_bind_addr *);
1163 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest,
1164 const struct sctp_bind_addr *src,
1165 enum sctp_scope scope, gfp_t gfp,
1166 int flags);
1167 int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
1168 const struct sctp_bind_addr *src,
1169 gfp_t gfp);
1170 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *,
1171 int new_size, __u8 addr_state, gfp_t gfp);
1172 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *);
1173 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *,
1174 struct sctp_sock *);
1175 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *,
1176 struct sctp_sock *, struct sctp_sock *);
1177 int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
1178 const union sctp_addr *addr);
1179 int sctp_bind_addrs_check(struct sctp_sock *sp,
1180 struct sctp_sock *sp2, int cnt2);
1181 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp,
1182 const union sctp_addr *addrs,
1183 int addrcnt,
1184 struct sctp_sock *opt);
1185 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
1186 int *addrs_len,
1187 gfp_t gfp);
1188 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len,
1189 __u16 port, gfp_t gfp);
1190
1191 enum sctp_scope sctp_scope(const union sctp_addr *addr);
1192 int sctp_in_scope(struct net *net, const union sctp_addr *addr,
1193 const enum sctp_scope scope);
1194 int sctp_is_any(struct sock *sk, const union sctp_addr *addr);
1195 int sctp_is_ep_boundall(struct sock *sk);
1196
1197
1198 /* What type of endpoint? */
1199 enum sctp_endpoint_type {
1200 SCTP_EP_TYPE_SOCKET,
1201 SCTP_EP_TYPE_ASSOCIATION,
1202 };
1203
1204 /*
1205 * A common base class to bridge the implmentation view of a
1206 * socket (usually listening) endpoint versus an association's
1207 * local endpoint.
1208 * This common structure is useful for several purposes:
1209 * 1) Common interface for lookup routines.
1210 * a) Subfunctions work for either endpoint or association
1211 * b) Single interface to lookup allows hiding the lookup lock rather
1212 * than acquiring it externally.
1213 * 2) Common interface for the inbound chunk handling/state machine.
1214 * 3) Common object handling routines for reference counting, etc.
1215 * 4) Disentangle association lookup from endpoint lookup, where we
1216 * do not have to find our endpoint to find our association.
1217 *
1218 */
1219
1220 struct sctp_ep_common {
1221 /* Fields to help us manage our entries in the hash tables. */
1222 struct hlist_node node;
1223 int hashent;
1224
1225 /* Runtime type information. What kind of endpoint is this? */
1226 enum sctp_endpoint_type type;
1227
1228 /* Some fields to help us manage this object.
1229 * refcnt - Reference count access to this object.
1230 * dead - Do not attempt to use this object.
1231 */
1232 refcount_t refcnt;
1233 bool dead;
1234
1235 /* What socket does this endpoint belong to? */
1236 struct sock *sk;
1237
1238 /* Cache netns and it won't change once set */
1239 struct net *net;
1240
1241 /* This is where we receive inbound chunks. */
1242 struct sctp_inq inqueue;
1243
1244 /* This substructure includes the defining parameters of the
1245 * endpoint:
1246 * bind_addr.port is our shared port number.
1247 * bind_addr.address_list is our set of local IP addresses.
1248 */
1249 struct sctp_bind_addr bind_addr;
1250 };
1251
1252
1253 /* RFC Section 1.4 Key Terms
1254 *
1255 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a
1256 * multi-homed host, an SCTP endpoint is represented to its peers as a
1257 * combination of a set of eligible destination transport addresses to
1258 * which SCTP packets can be sent and a set of eligible source
1259 * transport addresses from which SCTP packets can be received.
1260 * All transport addresses used by an SCTP endpoint must use the
1261 * same port number, but can use multiple IP addresses. A transport
1262 * address used by an SCTP endpoint must not be used by another
1263 * SCTP endpoint. In other words, a transport address is unique
1264 * to an SCTP endpoint.
1265 *
1266 * From an implementation perspective, each socket has one of these.
1267 * A TCP-style socket will have exactly one association on one of
1268 * these. An UDP-style socket will have multiple associations hanging
1269 * off one of these.
1270 */
1271
1272 struct sctp_endpoint {
1273 /* Common substructure for endpoint and association. */
1274 struct sctp_ep_common base;
1275
1276 /* Associations: A list of current associations and mappings
1277 * to the data consumers for each association. This
1278 * may be in the form of a hash table or other
1279 * implementation dependent structure. The data
1280 * consumers may be process identification
1281 * information such as file descriptors, named pipe
1282 * pointer, or table pointers dependent on how SCTP
1283 * is implemented.
1284 */
1285 /* This is really a list of struct sctp_association entries. */
1286 struct list_head asocs;
1287
1288 /* Secret Key: A secret key used by this endpoint to compute
1289 * the MAC. This SHOULD be a cryptographic quality
1290 * random number with a sufficient length.
1291 * Discussion in [RFC1750] can be helpful in
1292 * selection of the key.
1293 */
1294 __u8 secret_key[SCTP_SECRET_SIZE];
1295
1296 /* digest: This is a digest of the sctp cookie. This field is
1297 * only used on the receive path when we try to validate
1298 * that the cookie has not been tampered with. We put
1299 * this here so we pre-allocate this once and can re-use
1300 * on every receive.
1301 */
1302 __u8 *digest;
1303
1304 /* sendbuf acct. policy. */
1305 __u32 sndbuf_policy;
1306
1307 /* rcvbuf acct. policy. */
1308 __u32 rcvbuf_policy;
1309
1310 /* SCTP AUTH: array of the HMACs that will be allocated
1311 * we need this per association so that we don't serialize
1312 */
1313 struct crypto_shash **auth_hmacs;
1314
1315 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
1316 struct sctp_hmac_algo_param *auth_hmacs_list;
1317
1318 /* SCTP-AUTH: chunks to authenticate encoded into parameter */
1319 struct sctp_chunks_param *auth_chunk_list;
1320
1321 /* SCTP-AUTH: endpoint shared keys */
1322 struct list_head endpoint_shared_keys;
1323 __u16 active_key_id;
1324 __u8 ecn_enable:1,
1325 auth_enable:1,
1326 intl_enable:1,
1327 prsctp_enable:1,
1328 asconf_enable:1,
1329 reconf_enable:1;
1330
1331 __u8 strreset_enable;
1332
1333 /* Security identifiers from incoming (INIT). These are set by
1334 * security_sctp_assoc_request(). These will only be used by
1335 * SCTP TCP type sockets and peeled off connections as they
1336 * cause a new socket to be generated. security_sctp_sk_clone()
1337 * will then plug these into the new socket.
1338 */
1339
1340 u32 secid;
1341 u32 peer_secid;
1342 };
1343
1344 /* Recover the outter endpoint structure. */
sctp_ep(struct sctp_ep_common * base)1345 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base)
1346 {
1347 struct sctp_endpoint *ep;
1348
1349 ep = container_of(base, struct sctp_endpoint, base);
1350 return ep;
1351 }
1352
1353 /* These are function signatures for manipulating endpoints. */
1354 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t);
1355 void sctp_endpoint_free(struct sctp_endpoint *);
1356 void sctp_endpoint_put(struct sctp_endpoint *);
1357 void sctp_endpoint_hold(struct sctp_endpoint *);
1358 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *);
1359 struct sctp_association *sctp_endpoint_lookup_assoc(
1360 const struct sctp_endpoint *ep,
1361 const union sctp_addr *paddr,
1362 struct sctp_transport **);
1363 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep,
1364 const union sctp_addr *paddr);
1365 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *,
1366 struct net *, const union sctp_addr *);
1367 bool sctp_has_association(struct net *net, const union sctp_addr *laddr,
1368 const union sctp_addr *paddr);
1369
1370 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep,
1371 const struct sctp_association *asoc,
1372 enum sctp_cid cid, struct sctp_init_chunk *peer_init,
1373 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk);
1374 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk,
1375 const union sctp_addr *peer,
1376 struct sctp_init_chunk *init, gfp_t gfp);
1377 __u32 sctp_generate_tag(const struct sctp_endpoint *);
1378 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
1379
1380 struct sctp_inithdr_host {
1381 __u32 init_tag;
1382 __u32 a_rwnd;
1383 __u16 num_outbound_streams;
1384 __u16 num_inbound_streams;
1385 __u32 initial_tsn;
1386 };
1387
1388 struct sctp_stream_priorities {
1389 /* List of priorities scheduled */
1390 struct list_head prio_sched;
1391 /* List of streams scheduled */
1392 struct list_head active;
1393 /* The next stream in line */
1394 struct sctp_stream_out_ext *next;
1395 __u16 prio;
1396 };
1397
1398 struct sctp_stream_out_ext {
1399 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1];
1400 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1];
1401 struct list_head outq; /* chunks enqueued by this stream */
1402 union {
1403 struct {
1404 /* Scheduled streams list */
1405 struct list_head prio_list;
1406 struct sctp_stream_priorities *prio_head;
1407 };
1408 /* Fields used by RR scheduler */
1409 struct {
1410 struct list_head rr_list;
1411 };
1412 };
1413 };
1414
1415 struct sctp_stream_out {
1416 union {
1417 __u32 mid;
1418 __u16 ssn;
1419 };
1420 __u32 mid_uo;
1421 struct sctp_stream_out_ext *ext;
1422 __u8 state;
1423 };
1424
1425 struct sctp_stream_in {
1426 union {
1427 __u32 mid;
1428 __u16 ssn;
1429 };
1430 __u32 mid_uo;
1431 __u32 fsn;
1432 __u32 fsn_uo;
1433 char pd_mode;
1434 char pd_mode_uo;
1435 };
1436
1437 struct sctp_stream {
1438 GENRADIX(struct sctp_stream_out) out;
1439 GENRADIX(struct sctp_stream_in) in;
1440
1441 __u16 outcnt;
1442 __u16 incnt;
1443 /* Current stream being sent, if any */
1444 struct sctp_stream_out *out_curr;
1445 union {
1446 /* Fields used by priority scheduler */
1447 struct {
1448 /* List of priorities scheduled */
1449 struct list_head prio_list;
1450 };
1451 /* Fields used by RR scheduler */
1452 struct {
1453 /* List of streams scheduled */
1454 struct list_head rr_list;
1455 /* The next stream in line */
1456 struct sctp_stream_out_ext *rr_next;
1457 };
1458 };
1459 struct sctp_stream_interleave *si;
1460 };
1461
sctp_stream_out(struct sctp_stream * stream,__u16 sid)1462 static inline struct sctp_stream_out *sctp_stream_out(
1463 struct sctp_stream *stream,
1464 __u16 sid)
1465 {
1466 return genradix_ptr(&stream->out, sid);
1467 }
1468
sctp_stream_in(struct sctp_stream * stream,__u16 sid)1469 static inline struct sctp_stream_in *sctp_stream_in(
1470 struct sctp_stream *stream,
1471 __u16 sid)
1472 {
1473 return genradix_ptr(&stream->in, sid);
1474 }
1475
1476 #define SCTP_SO(s, i) sctp_stream_out((s), (i))
1477 #define SCTP_SI(s, i) sctp_stream_in((s), (i))
1478
1479 #define SCTP_STREAM_CLOSED 0x00
1480 #define SCTP_STREAM_OPEN 0x01
1481
sctp_datachk_len(const struct sctp_stream * stream)1482 static inline __u16 sctp_datachk_len(const struct sctp_stream *stream)
1483 {
1484 return stream->si->data_chunk_len;
1485 }
1486
sctp_datahdr_len(const struct sctp_stream * stream)1487 static inline __u16 sctp_datahdr_len(const struct sctp_stream *stream)
1488 {
1489 return stream->si->data_chunk_len - sizeof(struct sctp_chunkhdr);
1490 }
1491
sctp_ftsnchk_len(const struct sctp_stream * stream)1492 static inline __u16 sctp_ftsnchk_len(const struct sctp_stream *stream)
1493 {
1494 return stream->si->ftsn_chunk_len;
1495 }
1496
sctp_ftsnhdr_len(const struct sctp_stream * stream)1497 static inline __u16 sctp_ftsnhdr_len(const struct sctp_stream *stream)
1498 {
1499 return stream->si->ftsn_chunk_len - sizeof(struct sctp_chunkhdr);
1500 }
1501
1502 /* SCTP_GET_ASSOC_STATS counters */
1503 struct sctp_priv_assoc_stats {
1504 /* Maximum observed rto in the association during subsequent
1505 * observations. Value is set to 0 if no RTO measurement took place
1506 * The transport where the max_rto was observed is returned in
1507 * obs_rto_ipaddr
1508 */
1509 struct sockaddr_storage obs_rto_ipaddr;
1510 __u64 max_obs_rto;
1511 /* Total In and Out SACKs received and sent */
1512 __u64 isacks;
1513 __u64 osacks;
1514 /* Total In and Out packets received and sent */
1515 __u64 opackets;
1516 __u64 ipackets;
1517 /* Total retransmitted chunks */
1518 __u64 rtxchunks;
1519 /* TSN received > next expected */
1520 __u64 outofseqtsns;
1521 /* Duplicate Chunks received */
1522 __u64 idupchunks;
1523 /* Gap Ack Blocks received */
1524 __u64 gapcnt;
1525 /* Unordered data chunks sent and received */
1526 __u64 ouodchunks;
1527 __u64 iuodchunks;
1528 /* Ordered data chunks sent and received */
1529 __u64 oodchunks;
1530 __u64 iodchunks;
1531 /* Control chunks sent and received */
1532 __u64 octrlchunks;
1533 __u64 ictrlchunks;
1534 };
1535
1536 /* RFC2960
1537 *
1538 * 12. Recommended Transmission Control Block (TCB) Parameters
1539 *
1540 * This section details a recommended set of parameters that should
1541 * be contained within the TCB for an implementation. This section is
1542 * for illustrative purposes and should not be deemed as requirements
1543 * on an implementation or as an exhaustive list of all parameters
1544 * inside an SCTP TCB. Each implementation may need its own additional
1545 * parameters for optimization.
1546 */
1547
1548
1549 /* Here we have information about each individual association. */
1550 struct sctp_association {
1551
1552 /* A base structure common to endpoint and association.
1553 * In this context, it represents the associations's view
1554 * of the local endpoint of the association.
1555 */
1556 struct sctp_ep_common base;
1557
1558 /* Associations on the same socket. */
1559 struct list_head asocs;
1560
1561 /* association id. */
1562 sctp_assoc_t assoc_id;
1563
1564 /* This is our parent endpoint. */
1565 struct sctp_endpoint *ep;
1566
1567 /* These are those association elements needed in the cookie. */
1568 struct sctp_cookie c;
1569
1570 /* This is all information about our peer. */
1571 struct {
1572 /* transport_addr_list
1573 *
1574 * Peer : A list of SCTP transport addresses that the
1575 * Transport : peer is bound to. This information is derived
1576 * Address : from the INIT or INIT ACK and is used to
1577 * List : associate an inbound packet with a given
1578 * : association. Normally this information is
1579 * : hashed or keyed for quick lookup and access
1580 * : of the TCB.
1581 * : The list is also initialized with the list
1582 * : of addresses passed with the sctp_connectx()
1583 * : call.
1584 *
1585 * It is a list of SCTP_transport's.
1586 */
1587 struct list_head transport_addr_list;
1588
1589 /* rwnd
1590 *
1591 * Peer Rwnd : Current calculated value of the peer's rwnd.
1592 */
1593 __u32 rwnd;
1594
1595 /* transport_count
1596 *
1597 * Peer : A count of the number of peer addresses
1598 * Transport : in the Peer Transport Address List.
1599 * Address :
1600 * Count :
1601 */
1602 __u16 transport_count;
1603
1604 /* port
1605 * The transport layer port number.
1606 */
1607 __u16 port;
1608
1609 /* primary_path
1610 *
1611 * Primary : This is the current primary destination
1612 * Path : transport address of the peer endpoint. It
1613 * : may also specify a source transport address
1614 * : on this endpoint.
1615 *
1616 * All of these paths live on transport_addr_list.
1617 *
1618 * At the bakeoffs, we discovered that the intent of
1619 * primaryPath is that it only changes when the ULP
1620 * asks to have it changed. We add the activePath to
1621 * designate the connection we are currently using to
1622 * transmit new data and most control chunks.
1623 */
1624 struct sctp_transport *primary_path;
1625
1626 /* Cache the primary path address here, when we
1627 * need a an address for msg_name.
1628 */
1629 union sctp_addr primary_addr;
1630
1631 /* active_path
1632 * The path that we are currently using to
1633 * transmit new data and most control chunks.
1634 */
1635 struct sctp_transport *active_path;
1636
1637 /* retran_path
1638 *
1639 * RFC2960 6.4 Multi-homed SCTP Endpoints
1640 * ...
1641 * Furthermore, when its peer is multi-homed, an
1642 * endpoint SHOULD try to retransmit a chunk to an
1643 * active destination transport address that is
1644 * different from the last destination address to
1645 * which the DATA chunk was sent.
1646 */
1647 struct sctp_transport *retran_path;
1648
1649 /* Pointer to last transport I have sent on. */
1650 struct sctp_transport *last_sent_to;
1651
1652 /* This is the last transport I have received DATA on. */
1653 struct sctp_transport *last_data_from;
1654
1655 /*
1656 * Mapping An array of bits or bytes indicating which out of
1657 * Array order TSN's have been received (relative to the
1658 * Last Rcvd TSN). If no gaps exist, i.e. no out of
1659 * order packets have been received, this array
1660 * will be set to all zero. This structure may be
1661 * in the form of a circular buffer or bit array.
1662 *
1663 * Last Rcvd : This is the last TSN received in
1664 * TSN : sequence. This value is set initially by
1665 * : taking the peer's Initial TSN, received in
1666 * : the INIT or INIT ACK chunk, and subtracting
1667 * : one from it.
1668 *
1669 * Throughout most of the specification this is called the
1670 * "Cumulative TSN ACK Point". In this case, we
1671 * ignore the advice in 12.2 in favour of the term
1672 * used in the bulk of the text. This value is hidden
1673 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn().
1674 */
1675 struct sctp_tsnmap tsn_map;
1676
1677 /* This mask is used to disable sending the ASCONF chunk
1678 * with specified parameter to peer.
1679 */
1680 __be16 addip_disabled_mask;
1681
1682 /* These are capabilities which our peer advertised. */
1683 __u16 ecn_capable:1, /* Can peer do ECN? */
1684 ipv4_address:1, /* Peer understands IPv4 addresses? */
1685 ipv6_address:1, /* Peer understands IPv6 addresses? */
1686 hostname_address:1, /* Peer understands DNS addresses? */
1687 asconf_capable:1, /* Does peer support ADDIP? */
1688 prsctp_capable:1, /* Can peer do PR-SCTP? */
1689 reconf_capable:1, /* Can peer do RE-CONFIG? */
1690 intl_capable:1, /* Can peer do INTERLEAVE */
1691 auth_capable:1, /* Is peer doing SCTP-AUTH? */
1692 /* sack_needed:
1693 * This flag indicates if the next received
1694 * packet is to be responded to with a
1695 * SACK. This is initialized to 0. When a packet
1696 * is received sack_cnt is incremented. If this value
1697 * reaches 2 or more, a SACK is sent and the
1698 * value is reset to 0. Note: This is used only
1699 * when no DATA chunks are received out of
1700 * order. When DATA chunks are out of order,
1701 * SACK's are not delayed (see Section 6).
1702 */
1703 sack_needed:1, /* Do we need to sack the peer? */
1704 sack_generation:1,
1705 zero_window_announced:1;
1706
1707 __u32 sack_cnt;
1708
1709 __u32 adaptation_ind; /* Adaptation Code point. */
1710
1711 struct sctp_inithdr_host i;
1712 void *cookie;
1713 int cookie_len;
1714
1715 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk.
1716 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the
1717 * Initial TSN Value minus 1
1718 */
1719 __u32 addip_serial;
1720
1721 /* SCTP-AUTH: We need to know pears random number, hmac list
1722 * and authenticated chunk list. All that is part of the
1723 * cookie and these are just pointers to those locations
1724 */
1725 struct sctp_random_param *peer_random;
1726 struct sctp_chunks_param *peer_chunks;
1727 struct sctp_hmac_algo_param *peer_hmacs;
1728 } peer;
1729
1730 /* State : A state variable indicating what state the
1731 * : association is in, i.e. COOKIE-WAIT,
1732 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING,
1733 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT.
1734 *
1735 * Note: No "CLOSED" state is illustrated since if a
1736 * association is "CLOSED" its TCB SHOULD be removed.
1737 *
1738 * In this implementation we DO have a CLOSED
1739 * state which is used during initiation and shutdown.
1740 *
1741 * State takes values from SCTP_STATE_*.
1742 */
1743 enum sctp_state state;
1744
1745 /* Overall : The overall association error count.
1746 * Error Count : [Clear this any time I get something.]
1747 */
1748 int overall_error_count;
1749
1750 /* The cookie life I award for any cookie. */
1751 ktime_t cookie_life;
1752
1753 /* These are the association's initial, max, and min RTO values.
1754 * These values will be initialized by system defaults, but can
1755 * be modified via the SCTP_RTOINFO socket option.
1756 */
1757 unsigned long rto_initial;
1758 unsigned long rto_max;
1759 unsigned long rto_min;
1760
1761 /* Maximum number of new data packets that can be sent in a burst. */
1762 int max_burst;
1763
1764 /* This is the max_retrans value for the association. This value will
1765 * be initialized from system defaults, but can be
1766 * modified by the SCTP_ASSOCINFO socket option.
1767 */
1768 int max_retrans;
1769
1770 /* This is the partially failed retrans value for the transport
1771 * and will be initialized from the assocs value. This can be
1772 * changed using the SCTP_PEER_ADDR_THLDS socket option
1773 */
1774 __u16 pf_retrans;
1775 /* Used for primary path switchover. */
1776 __u16 ps_retrans;
1777
1778 /* Maximum number of times the endpoint will retransmit INIT */
1779 __u16 max_init_attempts;
1780
1781 /* How many times have we resent an INIT? */
1782 __u16 init_retries;
1783
1784 /* The largest timeout or RTO value to use in attempting an INIT */
1785 unsigned long max_init_timeo;
1786
1787 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
1788 * the destination address every heartbeat interval. This value
1789 * will be inherited by all new transports.
1790 */
1791 unsigned long hbinterval;
1792
1793 /* This is the max_retrans value for new transports in the
1794 * association.
1795 */
1796 __u16 pathmaxrxt;
1797
1798 __u32 flowlabel;
1799 __u8 dscp;
1800
1801 /* Flag that path mtu update is pending */
1802 __u8 pmtu_pending;
1803
1804 /* Association : The smallest PMTU discovered for all of the
1805 * PMTU : peer's transport addresses.
1806 */
1807 __u32 pathmtu;
1808
1809 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
1810 __u32 param_flags;
1811
1812 __u32 sackfreq;
1813 /* SACK delay timeout */
1814 unsigned long sackdelay;
1815
1816 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES];
1817 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES];
1818
1819 /* Transport to which SHUTDOWN chunk was last sent. */
1820 struct sctp_transport *shutdown_last_sent_to;
1821
1822 /* Transport to which INIT chunk was last sent. */
1823 struct sctp_transport *init_last_sent_to;
1824
1825 /* How many times have we resent a SHUTDOWN */
1826 int shutdown_retries;
1827
1828 /* Next TSN : The next TSN number to be assigned to a new
1829 * : DATA chunk. This is sent in the INIT or INIT
1830 * : ACK chunk to the peer and incremented each
1831 * : time a DATA chunk is assigned a TSN
1832 * : (normally just prior to transmit or during
1833 * : fragmentation).
1834 */
1835 __u32 next_tsn;
1836
1837 /*
1838 * Last Rcvd : This is the last TSN received in sequence. This value
1839 * TSN : is set initially by taking the peer's Initial TSN,
1840 * : received in the INIT or INIT ACK chunk, and
1841 * : subtracting one from it.
1842 *
1843 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point.
1844 */
1845
1846 __u32 ctsn_ack_point;
1847
1848 /* PR-SCTP Advanced.Peer.Ack.Point */
1849 __u32 adv_peer_ack_point;
1850
1851 /* Highest TSN that is acknowledged by incoming SACKs. */
1852 __u32 highest_sacked;
1853
1854 /* TSN marking the fast recovery exit point */
1855 __u32 fast_recovery_exit;
1856
1857 /* Flag to track the current fast recovery state */
1858 __u8 fast_recovery;
1859
1860 /* The number of unacknowledged data chunks. Reported through
1861 * the SCTP_STATUS sockopt.
1862 */
1863 __u16 unack_data;
1864
1865 /* The total number of data chunks that we've had to retransmit
1866 * as the result of a T3 timer expiration
1867 */
1868 __u32 rtx_data_chunks;
1869
1870 /* This is the association's receive buffer space. This value is used
1871 * to set a_rwnd field in an INIT or a SACK chunk.
1872 */
1873 __u32 rwnd;
1874
1875 /* This is the last advertised value of rwnd over a SACK chunk. */
1876 __u32 a_rwnd;
1877
1878 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed
1879 * to slop over a maximum of the association's frag_point.
1880 */
1881 __u32 rwnd_over;
1882
1883 /* Keeps treack of rwnd pressure. This happens when we have
1884 * a window, but not recevie buffer (i.e small packets). This one
1885 * is releases slowly (1 PMTU at a time ).
1886 */
1887 __u32 rwnd_press;
1888
1889 /* This is the sndbuf size in use for the association.
1890 * This corresponds to the sndbuf size for the association,
1891 * as specified in the sk->sndbuf.
1892 */
1893 int sndbuf_used;
1894
1895 /* This is the amount of memory that this association has allocated
1896 * in the receive path at any given time.
1897 */
1898 atomic_t rmem_alloc;
1899
1900 /* This is the wait queue head for send requests waiting on
1901 * the association sndbuf space.
1902 */
1903 wait_queue_head_t wait;
1904
1905 /* The message size at which SCTP fragmentation will occur. */
1906 __u32 frag_point;
1907 __u32 user_frag;
1908
1909 /* Counter used to count INIT errors. */
1910 int init_err_counter;
1911
1912 /* Count the number of INIT cycles (for doubling timeout). */
1913 int init_cycle;
1914
1915 /* Default send parameters. */
1916 __u16 default_stream;
1917 __u16 default_flags;
1918 __u32 default_ppid;
1919 __u32 default_context;
1920 __u32 default_timetolive;
1921
1922 /* Default receive parameters */
1923 __u32 default_rcv_context;
1924
1925 /* Stream arrays */
1926 struct sctp_stream stream;
1927
1928 /* All outbound chunks go through this structure. */
1929 struct sctp_outq outqueue;
1930
1931 /* A smart pipe that will handle reordering and fragmentation,
1932 * as well as handle passing events up to the ULP.
1933 */
1934 struct sctp_ulpq ulpq;
1935
1936 /* Last TSN that caused an ECNE Chunk to be sent. */
1937 __u32 last_ecne_tsn;
1938
1939 /* Last TSN that caused a CWR Chunk to be sent. */
1940 __u32 last_cwr_tsn;
1941
1942 /* How many duplicated TSNs have we seen? */
1943 int numduptsns;
1944
1945 /* These are to support
1946 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses
1947 * and Enforcement of Flow and Message Limits"
1948 * <draft-ietf-tsvwg-addip-sctp-02.txt>
1949 * or "ADDIP" for short.
1950 */
1951
1952
1953
1954 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1955 *
1956 * R1) One and only one ASCONF Chunk MAY be in transit and
1957 * unacknowledged at any one time. If a sender, after sending
1958 * an ASCONF chunk, decides it needs to transfer another
1959 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1960 * returns from the previous ASCONF Chunk before sending a
1961 * subsequent ASCONF. Note this restriction binds each side,
1962 * so at any time two ASCONF may be in-transit on any given
1963 * association (one sent from each endpoint).
1964 *
1965 * [This is our one-and-only-one ASCONF in flight. If we do
1966 * not have an ASCONF in flight, this is NULL.]
1967 */
1968 struct sctp_chunk *addip_last_asconf;
1969
1970 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk.
1971 *
1972 * This is needed to implement itmes E1 - E4 of the updated
1973 * spec. Here is the justification:
1974 *
1975 * Since the peer may bundle multiple ASCONF chunks toward us,
1976 * we now need the ability to cache multiple ACKs. The section
1977 * describes in detail how they are cached and cleaned up.
1978 */
1979 struct list_head asconf_ack_list;
1980
1981 /* These ASCONF chunks are waiting to be sent.
1982 *
1983 * These chunaks can't be pushed to outqueue until receiving
1984 * ASCONF_ACK for the previous ASCONF indicated by
1985 * addip_last_asconf, so as to guarantee that only one ASCONF
1986 * is in flight at any time.
1987 *
1988 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
1989 *
1990 * In defining the ASCONF Chunk transfer procedures, it is
1991 * essential that these transfers MUST NOT cause congestion
1992 * within the network. To achieve this, we place these
1993 * restrictions on the transfer of ASCONF Chunks:
1994 *
1995 * R1) One and only one ASCONF Chunk MAY be in transit and
1996 * unacknowledged at any one time. If a sender, after sending
1997 * an ASCONF chunk, decides it needs to transfer another
1998 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk
1999 * returns from the previous ASCONF Chunk before sending a
2000 * subsequent ASCONF. Note this restriction binds each side,
2001 * so at any time two ASCONF may be in-transit on any given
2002 * association (one sent from each endpoint).
2003 *
2004 *
2005 * [I really think this is EXACTLY the sort of intelligence
2006 * which already resides in sctp_outq. Please move this
2007 * queue and its supporting logic down there. --piggy]
2008 */
2009 struct list_head addip_chunk_list;
2010
2011 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2012 *
2013 * A2) A serial number should be assigned to the Chunk. The
2014 * serial number SHOULD be a monotonically increasing
2015 * number. The serial number SHOULD be initialized at
2016 * the start of the association to the same value as the
2017 * Initial TSN and every time a new ASCONF chunk is created
2018 * it is incremented by one after assigning the serial number
2019 * to the newly created chunk.
2020 *
2021 * ADDIP
2022 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF)
2023 *
2024 * Serial Number : 32 bits (unsigned integer)
2025 *
2026 * This value represents a Serial Number for the ASCONF
2027 * Chunk. The valid range of Serial Number is from 0 to
2028 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0
2029 * after reaching 4294967295.
2030 */
2031 __u32 addip_serial;
2032 int src_out_of_asoc_ok;
2033 union sctp_addr *asconf_addr_del_pending;
2034 struct sctp_transport *new_transport;
2035
2036 /* SCTP AUTH: list of the endpoint shared keys. These
2037 * keys are provided out of band by the user applicaton
2038 * and can't change during the lifetime of the association
2039 */
2040 struct list_head endpoint_shared_keys;
2041
2042 /* SCTP AUTH:
2043 * The current generated assocaition shared key (secret)
2044 */
2045 struct sctp_auth_bytes *asoc_shared_key;
2046 struct sctp_shared_key *shkey;
2047
2048 /* SCTP AUTH: hmac id of the first peer requested algorithm
2049 * that we support.
2050 */
2051 __u16 default_hmac_id;
2052
2053 __u16 active_key_id;
2054
2055 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */
2056 temp:1, /* Is it a temporary association? */
2057 pf_expose:2, /* Expose pf state? */
2058 force_delay:1;
2059
2060 __u8 strreset_enable;
2061 __u8 strreset_outstanding; /* request param count on the fly */
2062
2063 __u32 strreset_outseq; /* Update after receiving response */
2064 __u32 strreset_inseq; /* Update after receiving request */
2065 __u32 strreset_result[2]; /* save the results of last 2 responses */
2066
2067 struct sctp_chunk *strreset_chunk; /* save request chunk */
2068
2069 struct sctp_priv_assoc_stats stats;
2070
2071 int sent_cnt_removable;
2072
2073 __u16 subscribe;
2074
2075 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1];
2076 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1];
2077
2078 struct rcu_head rcu;
2079 };
2080
2081
2082 /* An eyecatcher for determining if we are really looking at an
2083 * association data structure.
2084 */
2085 enum {
2086 SCTP_ASSOC_EYECATCHER = 0xa550c123,
2087 };
2088
2089 /* Recover the outter association structure. */
sctp_assoc(struct sctp_ep_common * base)2090 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base)
2091 {
2092 struct sctp_association *asoc;
2093
2094 asoc = container_of(base, struct sctp_association, base);
2095 return asoc;
2096 }
2097
2098 /* These are function signatures for manipulating associations. */
2099
2100
2101 struct sctp_association *
2102 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk,
2103 enum sctp_scope scope, gfp_t gfp);
2104 void sctp_association_free(struct sctp_association *);
2105 void sctp_association_put(struct sctp_association *);
2106 void sctp_association_hold(struct sctp_association *);
2107
2108 struct sctp_transport *sctp_assoc_choose_alter_transport(
2109 struct sctp_association *, struct sctp_transport *);
2110 void sctp_assoc_update_retran_path(struct sctp_association *);
2111 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *,
2112 const union sctp_addr *);
2113 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
2114 const union sctp_addr *laddr);
2115 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *,
2116 const union sctp_addr *address,
2117 const gfp_t gfp,
2118 const int peer_state);
2119 void sctp_assoc_del_peer(struct sctp_association *asoc,
2120 const union sctp_addr *addr);
2121 void sctp_assoc_rm_peer(struct sctp_association *asoc,
2122 struct sctp_transport *peer);
2123 void sctp_assoc_control_transport(struct sctp_association *asoc,
2124 struct sctp_transport *transport,
2125 enum sctp_transport_cmd command,
2126 sctp_sn_error_t error);
2127 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32);
2128 void sctp_assoc_migrate(struct sctp_association *, struct sock *);
2129 int sctp_assoc_update(struct sctp_association *old,
2130 struct sctp_association *new);
2131
2132 __u32 sctp_association_get_next_tsn(struct sctp_association *);
2133
2134 void sctp_assoc_update_frag_point(struct sctp_association *asoc);
2135 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu);
2136 void sctp_assoc_sync_pmtu(struct sctp_association *asoc);
2137 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int);
2138 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int);
2139 void sctp_assoc_set_primary(struct sctp_association *,
2140 struct sctp_transport *);
2141 void sctp_assoc_del_nonprimary_peers(struct sctp_association *,
2142 struct sctp_transport *);
2143 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc,
2144 enum sctp_scope scope, gfp_t gfp);
2145 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *,
2146 struct sctp_cookie*,
2147 gfp_t gfp);
2148 int sctp_assoc_set_id(struct sctp_association *, gfp_t);
2149 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc);
2150 struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
2151 const struct sctp_association *asoc,
2152 __be32 serial);
2153 void sctp_asconf_queue_teardown(struct sctp_association *asoc);
2154
2155 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
2156 const union sctp_addr *ss2);
2157 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc);
2158
2159 /* A convenience structure to parse out SCTP specific CMSGs. */
2160 struct sctp_cmsgs {
2161 struct sctp_initmsg *init;
2162 struct sctp_sndrcvinfo *srinfo;
2163 struct sctp_sndinfo *sinfo;
2164 struct sctp_prinfo *prinfo;
2165 struct sctp_authinfo *authinfo;
2166 struct msghdr *addrs_msg;
2167 };
2168
2169 /* Structure for tracking memory objects */
2170 struct sctp_dbg_objcnt_entry {
2171 char *label;
2172 atomic_t *counter;
2173 };
2174
2175 #endif /* __sctp_structs_h__ */
2176
