1 /* SCTP kernel implementation 2 * (C) Copyright IBM Corp. 2001, 2004 3 * Copyright (c) 1999-2000 Cisco, Inc. 4 * Copyright (c) 1999-2001 Motorola, Inc. 5 * Copyright (c) 2001 Intel Corp. 6 * 7 * This file is part of the SCTP kernel implementation 8 * 9 * This SCTP implementation is free software; 10 * you can redistribute it and/or modify it under the terms of 11 * the GNU General Public License as published by 12 * the Free Software Foundation; either version 2, or (at your option) 13 * any later version. 14 * 15 * This SCTP implementation is distributed in the hope that it 16 * will be useful, but WITHOUT ANY WARRANTY; without even the implied 17 * ************************ 18 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 19 * See the GNU General Public License for more details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with GNU CC; see the file COPYING. If not, write to 23 * the Free Software Foundation, 59 Temple Place - Suite 330, 24 * Boston, MA 02111-1307, USA. 25 * 26 * Please send any bug reports or fixes you make to the 27 * email addresses: 28 * lksctp developers <lksctp-developers@lists.sourceforge.net> 29 * 30 * Or submit a bug report through the following website: 31 * http://www.sf.net/projects/lksctp 32 * 33 * Written or modified by: 34 * Randall Stewart <randall@sctp.chicago.il.us> 35 * Ken Morneau <kmorneau@cisco.com> 36 * Qiaobing Xie <qxie1@email.mot.com> 37 * La Monte H.P. Yarroll <piggy@acm.org> 38 * Karl Knutson <karl@athena.chicago.il.us> 39 * Jon Grimm <jgrimm@us.ibm.com> 40 * Xingang Guo <xingang.guo@intel.com> 41 * Hui Huang <hui.huang@nokia.com> 42 * Sridhar Samudrala <sri@us.ibm.com> 43 * Daisy Chang <daisyc@us.ibm.com> 44 * Dajiang Zhang <dajiang.zhang@nokia.com> 45 * Ardelle Fan <ardelle.fan@intel.com> 46 * Ryan Layer <rmlayer@us.ibm.com> 47 * Anup Pemmaiah <pemmaiah@cc.usu.edu> 48 * Kevin Gao <kevin.gao@intel.com> 49 * 50 * Any bugs reported given to us we will try to fix... any fixes shared will 51 * be incorporated into the next SCTP release. 52 */ 53 54 #ifndef __sctp_structs_h__ 55 #define __sctp_structs_h__ 56 57 #include <linux/time.h> /* We get struct timespec. */ 58 #include <linux/socket.h> /* linux/in.h needs this!! */ 59 #include <linux/in.h> /* We get struct sockaddr_in. */ 60 #include <linux/in6.h> /* We get struct in6_addr */ 61 #include <linux/ipv6.h> 62 #include <asm/param.h> /* We get MAXHOSTNAMELEN. */ 63 #include <linux/atomic.h> /* This gets us atomic counters. */ 64 #include <linux/skbuff.h> /* We need sk_buff_head. */ 65 #include <linux/workqueue.h> /* We need tq_struct. */ 66 #include <linux/sctp.h> /* We need sctp* header structs. */ 67 #include <net/sctp/auth.h> /* We need auth specific structs */ 68 69 /* A convenience structure for handling sockaddr structures. 70 * We should wean ourselves off this. 71 */ 72 union sctp_addr { 73 struct sockaddr_in v4; 74 struct sockaddr_in6 v6; 75 struct sockaddr sa; 76 }; 77 78 /* Forward declarations for data structures. */ 79 struct sctp_globals; 80 struct sctp_endpoint; 81 struct sctp_association; 82 struct sctp_transport; 83 struct sctp_packet; 84 struct sctp_chunk; 85 struct sctp_inq; 86 struct sctp_outq; 87 struct sctp_bind_addr; 88 struct sctp_ulpq; 89 struct sctp_ep_common; 90 struct sctp_ssnmap; 91 struct crypto_hash; 92 93 94 #include <net/sctp/tsnmap.h> 95 #include <net/sctp/ulpevent.h> 96 #include <net/sctp/ulpqueue.h> 97 98 /* Structures useful for managing bind/connect. */ 99 100 struct sctp_bind_bucket { 101 unsigned short port; 102 unsigned short fastreuse; 103 struct hlist_node node; 104 struct hlist_head owner; 105 }; 106 107 struct sctp_bind_hashbucket { 108 spinlock_t lock; 109 struct hlist_head chain; 110 }; 111 112 /* Used for hashing all associations. */ 113 struct sctp_hashbucket { 114 rwlock_t lock; 115 struct hlist_head chain; 116 } __attribute__((__aligned__(8))); 117 118 119 /* The SCTP globals structure. */ 120 extern struct sctp_globals { 121 /* RFC2960 Section 14. Suggested SCTP Protocol Parameter Values 122 * 123 * The following protocol parameters are RECOMMENDED: 124 * 125 * RTO.Initial - 3 seconds 126 * RTO.Min - 1 second 127 * RTO.Max - 60 seconds 128 * RTO.Alpha - 1/8 (3 when converted to right shifts.) 129 * RTO.Beta - 1/4 (2 when converted to right shifts.) 130 */ 131 unsigned int rto_initial; 132 unsigned int rto_min; 133 unsigned int rto_max; 134 135 /* Note: rto_alpha and rto_beta are really defined as inverse 136 * powers of two to facilitate integer operations. 137 */ 138 int rto_alpha; 139 int rto_beta; 140 141 /* Max.Burst - 4 */ 142 int max_burst; 143 144 /* Whether Cookie Preservative is enabled(1) or not(0) */ 145 int cookie_preserve_enable; 146 147 /* Valid.Cookie.Life - 60 seconds */ 148 unsigned int valid_cookie_life; 149 150 /* Delayed SACK timeout 200ms default*/ 151 unsigned int sack_timeout; 152 153 /* HB.interval - 30 seconds */ 154 unsigned int hb_interval; 155 156 /* Association.Max.Retrans - 10 attempts 157 * Path.Max.Retrans - 5 attempts (per destination address) 158 * Max.Init.Retransmits - 8 attempts 159 */ 160 int max_retrans_association; 161 int max_retrans_path; 162 int max_retrans_init; 163 164 /* Potentially-Failed.Max.Retrans sysctl value 165 * taken from: 166 * http://tools.ietf.org/html/draft-nishida-tsvwg-sctp-failover-05 167 */ 168 int pf_retrans; 169 170 /* 171 * Policy for preforming sctp/socket accounting 172 * 0 - do socket level accounting, all assocs share sk_sndbuf 173 * 1 - do sctp accounting, each asoc may use sk_sndbuf bytes 174 */ 175 int sndbuf_policy; 176 177 /* 178 * Policy for preforming sctp/socket accounting 179 * 0 - do socket level accounting, all assocs share sk_rcvbuf 180 * 1 - do sctp accounting, each asoc may use sk_rcvbuf bytes 181 */ 182 int rcvbuf_policy; 183 184 /* The following variables are implementation specific. */ 185 186 /* Default initialization values to be applied to new associations. */ 187 __u16 max_instreams; 188 __u16 max_outstreams; 189 190 /* This is a list of groups of functions for each address 191 * family that we support. 192 */ 193 struct list_head address_families; 194 195 /* This is the hash of all endpoints. */ 196 int ep_hashsize; 197 struct sctp_hashbucket *ep_hashtable; 198 199 /* This is the hash of all associations. */ 200 int assoc_hashsize; 201 struct sctp_hashbucket *assoc_hashtable; 202 203 /* This is the sctp port control hash. */ 204 int port_hashsize; 205 struct sctp_bind_hashbucket *port_hashtable; 206 207 /* This is the global local address list. 208 * We actively maintain this complete list of addresses on 209 * the system by catching address add/delete events. 210 * 211 * It is a list of sctp_sockaddr_entry. 212 */ 213 struct list_head local_addr_list; 214 int default_auto_asconf; 215 struct list_head addr_waitq; 216 struct timer_list addr_wq_timer; 217 struct list_head auto_asconf_splist; 218 spinlock_t addr_wq_lock; 219 220 /* Lock that protects the local_addr_list writers */ 221 spinlock_t addr_list_lock; 222 223 /* Flag to indicate if addip is enabled. */ 224 int addip_enable; 225 int addip_noauth_enable; 226 227 /* Flag to indicate if PR-SCTP is enabled. */ 228 int prsctp_enable; 229 230 /* Flag to idicate if SCTP-AUTH is enabled */ 231 int auth_enable; 232 233 /* 234 * Policy to control SCTP IPv4 address scoping 235 * 0 - Disable IPv4 address scoping 236 * 1 - Enable IPv4 address scoping 237 * 2 - Selectively allow only IPv4 private addresses 238 * 3 - Selectively allow only IPv4 link local address 239 */ 240 int ipv4_scope_policy; 241 242 /* Flag to indicate whether computing and verifying checksum 243 * is disabled. */ 244 bool checksum_disable; 245 246 /* Threshold for rwnd update SACKS. Receive buffer shifted this many 247 * bits is an indicator of when to send and window update SACK. 248 */ 249 int rwnd_update_shift; 250 251 /* Threshold for autoclose timeout, in seconds. */ 252 unsigned long max_autoclose; 253 } sctp_globals; 254 255 #define sctp_rto_initial (sctp_globals.rto_initial) 256 #define sctp_rto_min (sctp_globals.rto_min) 257 #define sctp_rto_max (sctp_globals.rto_max) 258 #define sctp_rto_alpha (sctp_globals.rto_alpha) 259 #define sctp_rto_beta (sctp_globals.rto_beta) 260 #define sctp_max_burst (sctp_globals.max_burst) 261 #define sctp_valid_cookie_life (sctp_globals.valid_cookie_life) 262 #define sctp_cookie_preserve_enable (sctp_globals.cookie_preserve_enable) 263 #define sctp_max_retrans_association (sctp_globals.max_retrans_association) 264 #define sctp_sndbuf_policy (sctp_globals.sndbuf_policy) 265 #define sctp_rcvbuf_policy (sctp_globals.rcvbuf_policy) 266 #define sctp_max_retrans_path (sctp_globals.max_retrans_path) 267 #define sctp_pf_retrans (sctp_globals.pf_retrans) 268 #define sctp_max_retrans_init (sctp_globals.max_retrans_init) 269 #define sctp_sack_timeout (sctp_globals.sack_timeout) 270 #define sctp_hb_interval (sctp_globals.hb_interval) 271 #define sctp_max_instreams (sctp_globals.max_instreams) 272 #define sctp_max_outstreams (sctp_globals.max_outstreams) 273 #define sctp_address_families (sctp_globals.address_families) 274 #define sctp_ep_hashsize (sctp_globals.ep_hashsize) 275 #define sctp_ep_hashtable (sctp_globals.ep_hashtable) 276 #define sctp_assoc_hashsize (sctp_globals.assoc_hashsize) 277 #define sctp_assoc_hashtable (sctp_globals.assoc_hashtable) 278 #define sctp_port_hashsize (sctp_globals.port_hashsize) 279 #define sctp_port_hashtable (sctp_globals.port_hashtable) 280 #define sctp_local_addr_list (sctp_globals.local_addr_list) 281 #define sctp_local_addr_lock (sctp_globals.addr_list_lock) 282 #define sctp_auto_asconf_splist (sctp_globals.auto_asconf_splist) 283 #define sctp_addr_waitq (sctp_globals.addr_waitq) 284 #define sctp_addr_wq_timer (sctp_globals.addr_wq_timer) 285 #define sctp_addr_wq_lock (sctp_globals.addr_wq_lock) 286 #define sctp_default_auto_asconf (sctp_globals.default_auto_asconf) 287 #define sctp_scope_policy (sctp_globals.ipv4_scope_policy) 288 #define sctp_addip_enable (sctp_globals.addip_enable) 289 #define sctp_addip_noauth (sctp_globals.addip_noauth_enable) 290 #define sctp_prsctp_enable (sctp_globals.prsctp_enable) 291 #define sctp_auth_enable (sctp_globals.auth_enable) 292 #define sctp_checksum_disable (sctp_globals.checksum_disable) 293 #define sctp_rwnd_upd_shift (sctp_globals.rwnd_update_shift) 294 #define sctp_max_autoclose (sctp_globals.max_autoclose) 295 296 /* SCTP Socket type: UDP or TCP style. */ 297 typedef enum { 298 SCTP_SOCKET_UDP = 0, 299 SCTP_SOCKET_UDP_HIGH_BANDWIDTH, 300 SCTP_SOCKET_TCP 301 } sctp_socket_type_t; 302 303 /* Per socket SCTP information. */ 304 struct sctp_sock { 305 /* inet_sock has to be the first member of sctp_sock */ 306 struct inet_sock inet; 307 /* What kind of a socket is this? */ 308 sctp_socket_type_t type; 309 310 /* PF_ family specific functions. */ 311 struct sctp_pf *pf; 312 313 /* Access to HMAC transform. */ 314 struct crypto_hash *hmac; 315 316 /* What is our base endpointer? */ 317 struct sctp_endpoint *ep; 318 319 struct sctp_bind_bucket *bind_hash; 320 /* Various Socket Options. */ 321 __u16 default_stream; 322 __u32 default_ppid; 323 __u16 default_flags; 324 __u32 default_context; 325 __u32 default_timetolive; 326 __u32 default_rcv_context; 327 int max_burst; 328 329 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 330 * the destination address every heartbeat interval. This value 331 * will be inherited by all new associations. 332 */ 333 __u32 hbinterval; 334 335 /* This is the max_retrans value for new associations. */ 336 __u16 pathmaxrxt; 337 338 /* The initial Path MTU to use for new associations. */ 339 __u32 pathmtu; 340 341 /* The default SACK delay timeout for new associations. */ 342 __u32 sackdelay; 343 __u32 sackfreq; 344 345 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 346 __u32 param_flags; 347 348 struct sctp_initmsg initmsg; 349 struct sctp_rtoinfo rtoinfo; 350 struct sctp_paddrparams paddrparam; 351 struct sctp_event_subscribe subscribe; 352 struct sctp_assocparams assocparams; 353 int user_frag; 354 __u32 autoclose; 355 __u8 nodelay; 356 __u8 disable_fragments; 357 __u8 v4mapped; 358 __u8 frag_interleave; 359 __u32 adaptation_ind; 360 __u32 pd_point; 361 362 atomic_t pd_mode; 363 /* Receive to here while partial delivery is in effect. */ 364 struct sk_buff_head pd_lobby; 365 struct list_head auto_asconf_list; 366 int do_auto_asconf; 367 }; 368 369 static inline struct sctp_sock *sctp_sk(const struct sock *sk) 370 { 371 return (struct sctp_sock *)sk; 372 } 373 374 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp) 375 { 376 return (struct sock *)sp; 377 } 378 379 #if IS_ENABLED(CONFIG_IPV6) 380 struct sctp6_sock { 381 struct sctp_sock sctp; 382 struct ipv6_pinfo inet6; 383 }; 384 #endif /* CONFIG_IPV6 */ 385 386 387 /* This is our APPLICATION-SPECIFIC state cookie. 388 * THIS IS NOT DICTATED BY THE SPECIFICATION. 389 */ 390 /* These are the parts of an association which we send in the cookie. 391 * Most of these are straight out of: 392 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB) 393 * 394 */ 395 396 struct sctp_cookie { 397 398 /* My : Tag expected in every inbound packet and sent 399 * Verification: in the INIT or INIT ACK chunk. 400 * Tag : 401 */ 402 __u32 my_vtag; 403 404 /* Peer's : Tag expected in every outbound packet except 405 * Verification: in the INIT chunk. 406 * Tag : 407 */ 408 __u32 peer_vtag; 409 410 /* The rest of these are not from the spec, but really need to 411 * be in the cookie. 412 */ 413 414 /* My Tie Tag : Assist in discovering a restarting association. */ 415 __u32 my_ttag; 416 417 /* Peer's Tie Tag: Assist in discovering a restarting association. */ 418 __u32 peer_ttag; 419 420 /* When does this cookie expire? */ 421 struct timeval expiration; 422 423 /* Number of inbound/outbound streams which are set 424 * and negotiated during the INIT process. 425 */ 426 __u16 sinit_num_ostreams; 427 __u16 sinit_max_instreams; 428 429 /* This is the first sequence number I used. */ 430 __u32 initial_tsn; 431 432 /* This holds the originating address of the INIT packet. */ 433 union sctp_addr peer_addr; 434 435 /* IG Section 2.35.3 436 * Include the source port of the INIT-ACK 437 */ 438 __u16 my_port; 439 440 __u8 prsctp_capable; 441 442 /* Padding for future use */ 443 __u8 padding; 444 445 __u32 adaptation_ind; 446 447 __u8 auth_random[sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH]; 448 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2]; 449 __u8 auth_chunks[sizeof(sctp_paramhdr_t) + SCTP_AUTH_MAX_CHUNKS]; 450 451 /* This is a shim for my peer's INIT packet, followed by 452 * a copy of the raw address list of the association. 453 * The length of the raw address list is saved in the 454 * raw_addr_list_len field, which will be used at the time when 455 * the association TCB is re-constructed from the cookie. 456 */ 457 __u32 raw_addr_list_len; 458 struct sctp_init_chunk peer_init[0]; 459 }; 460 461 462 /* The format of our cookie that we send to our peer. */ 463 struct sctp_signed_cookie { 464 __u8 signature[SCTP_SECRET_SIZE]; 465 __u32 __pad; /* force sctp_cookie alignment to 64 bits */ 466 struct sctp_cookie c; 467 } __packed; 468 469 /* This is another convenience type to allocate memory for address 470 * params for the maximum size and pass such structures around 471 * internally. 472 */ 473 union sctp_addr_param { 474 struct sctp_paramhdr p; 475 struct sctp_ipv4addr_param v4; 476 struct sctp_ipv6addr_param v6; 477 }; 478 479 /* A convenience type to allow walking through the various 480 * parameters and avoid casting all over the place. 481 */ 482 union sctp_params { 483 void *v; 484 struct sctp_paramhdr *p; 485 struct sctp_cookie_preserve_param *life; 486 struct sctp_hostname_param *dns; 487 struct sctp_cookie_param *cookie; 488 struct sctp_supported_addrs_param *sat; 489 struct sctp_ipv4addr_param *v4; 490 struct sctp_ipv6addr_param *v6; 491 union sctp_addr_param *addr; 492 struct sctp_adaptation_ind_param *aind; 493 struct sctp_supported_ext_param *ext; 494 struct sctp_random_param *random; 495 struct sctp_chunks_param *chunks; 496 struct sctp_hmac_algo_param *hmac_algo; 497 struct sctp_addip_param *addip; 498 }; 499 500 /* RFC 2960. Section 3.3.5 Heartbeat. 501 * Heartbeat Information: variable length 502 * The Sender-specific Heartbeat Info field should normally include 503 * information about the sender's current time when this HEARTBEAT 504 * chunk is sent and the destination transport address to which this 505 * HEARTBEAT is sent (see Section 8.3). 506 */ 507 typedef struct sctp_sender_hb_info { 508 struct sctp_paramhdr param_hdr; 509 union sctp_addr daddr; 510 unsigned long sent_at; 511 __u64 hb_nonce; 512 } __packed sctp_sender_hb_info_t; 513 514 /* 515 * RFC 2960 1.3.2 Sequenced Delivery within Streams 516 * 517 * The term "stream" is used in SCTP to refer to a sequence of user 518 * messages that are to be delivered to the upper-layer protocol in 519 * order with respect to other messages within the same stream. This is 520 * in contrast to its usage in TCP, where it refers to a sequence of 521 * bytes (in this document a byte is assumed to be eight bits). 522 * ... 523 * 524 * This is the structure we use to track both our outbound and inbound 525 * SSN, or Stream Sequence Numbers. 526 */ 527 528 struct sctp_stream { 529 __u16 *ssn; 530 unsigned int len; 531 }; 532 533 struct sctp_ssnmap { 534 struct sctp_stream in; 535 struct sctp_stream out; 536 int malloced; 537 }; 538 539 struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out, 540 gfp_t gfp); 541 void sctp_ssnmap_free(struct sctp_ssnmap *map); 542 void sctp_ssnmap_clear(struct sctp_ssnmap *map); 543 544 /* What is the current SSN number for this stream? */ 545 static inline __u16 sctp_ssn_peek(struct sctp_stream *stream, __u16 id) 546 { 547 return stream->ssn[id]; 548 } 549 550 /* Return the next SSN number for this stream. */ 551 static inline __u16 sctp_ssn_next(struct sctp_stream *stream, __u16 id) 552 { 553 return stream->ssn[id]++; 554 } 555 556 /* Skip over this ssn and all below. */ 557 static inline void sctp_ssn_skip(struct sctp_stream *stream, __u16 id, 558 __u16 ssn) 559 { 560 stream->ssn[id] = ssn+1; 561 } 562 563 /* 564 * Pointers to address related SCTP functions. 565 * (i.e. things that depend on the address family.) 566 */ 567 struct sctp_af { 568 int (*sctp_xmit) (struct sk_buff *skb, 569 struct sctp_transport *); 570 int (*setsockopt) (struct sock *sk, 571 int level, 572 int optname, 573 char __user *optval, 574 unsigned int optlen); 575 int (*getsockopt) (struct sock *sk, 576 int level, 577 int optname, 578 char __user *optval, 579 int __user *optlen); 580 int (*compat_setsockopt) (struct sock *sk, 581 int level, 582 int optname, 583 char __user *optval, 584 unsigned int optlen); 585 int (*compat_getsockopt) (struct sock *sk, 586 int level, 587 int optname, 588 char __user *optval, 589 int __user *optlen); 590 void (*get_dst) (struct sctp_transport *t, 591 union sctp_addr *saddr, 592 struct flowi *fl, 593 struct sock *sk); 594 void (*get_saddr) (struct sctp_sock *sk, 595 struct sctp_transport *t, 596 struct flowi *fl); 597 void (*copy_addrlist) (struct list_head *, 598 struct net_device *); 599 int (*cmp_addr) (const union sctp_addr *addr1, 600 const union sctp_addr *addr2); 601 void (*addr_copy) (union sctp_addr *dst, 602 union sctp_addr *src); 603 void (*from_skb) (union sctp_addr *, 604 struct sk_buff *skb, 605 int saddr); 606 void (*from_sk) (union sctp_addr *, 607 struct sock *sk); 608 void (*to_sk_saddr) (union sctp_addr *, 609 struct sock *sk); 610 void (*to_sk_daddr) (union sctp_addr *, 611 struct sock *sk); 612 void (*from_addr_param) (union sctp_addr *, 613 union sctp_addr_param *, 614 __be16 port, int iif); 615 int (*to_addr_param) (const union sctp_addr *, 616 union sctp_addr_param *); 617 int (*addr_valid) (union sctp_addr *, 618 struct sctp_sock *, 619 const struct sk_buff *); 620 sctp_scope_t (*scope) (union sctp_addr *); 621 void (*inaddr_any) (union sctp_addr *, __be16); 622 int (*is_any) (const union sctp_addr *); 623 int (*available) (union sctp_addr *, 624 struct sctp_sock *); 625 int (*skb_iif) (const struct sk_buff *sk); 626 int (*is_ce) (const struct sk_buff *sk); 627 void (*seq_dump_addr)(struct seq_file *seq, 628 union sctp_addr *addr); 629 void (*ecn_capable)(struct sock *sk); 630 __u16 net_header_len; 631 int sockaddr_len; 632 sa_family_t sa_family; 633 struct list_head list; 634 }; 635 636 struct sctp_af *sctp_get_af_specific(sa_family_t); 637 int sctp_register_af(struct sctp_af *); 638 639 /* Protocol family functions. */ 640 struct sctp_pf { 641 void (*event_msgname)(struct sctp_ulpevent *, char *, int *); 642 void (*skb_msgname) (struct sk_buff *, char *, int *); 643 int (*af_supported) (sa_family_t, struct sctp_sock *); 644 int (*cmp_addr) (const union sctp_addr *, 645 const union sctp_addr *, 646 struct sctp_sock *); 647 int (*bind_verify) (struct sctp_sock *, union sctp_addr *); 648 int (*send_verify) (struct sctp_sock *, union sctp_addr *); 649 int (*supported_addrs)(const struct sctp_sock *, __be16 *); 650 struct sock *(*create_accept_sk) (struct sock *sk, 651 struct sctp_association *asoc); 652 void (*addr_v4map) (struct sctp_sock *, union sctp_addr *); 653 struct sctp_af *af; 654 }; 655 656 657 /* Structure to track chunk fragments that have been acked, but peer 658 * fragments of the same message have not. 659 */ 660 struct sctp_datamsg { 661 /* Chunks waiting to be submitted to lower layer. */ 662 struct list_head chunks; 663 /* Reference counting. */ 664 atomic_t refcnt; 665 /* When is this message no longer interesting to the peer? */ 666 unsigned long expires_at; 667 /* Did the messenge fail to send? */ 668 int send_error; 669 u8 send_failed:1, 670 can_abandon:1, /* can chunks from this message can be abandoned. */ 671 can_delay; /* should this message be Nagle delayed */ 672 }; 673 674 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *, 675 struct sctp_sndrcvinfo *, 676 struct msghdr *, int len); 677 void sctp_datamsg_free(struct sctp_datamsg *); 678 void sctp_datamsg_put(struct sctp_datamsg *); 679 void sctp_chunk_fail(struct sctp_chunk *, int error); 680 int sctp_chunk_abandoned(struct sctp_chunk *); 681 682 /* RFC2960 1.4 Key Terms 683 * 684 * o Chunk: A unit of information within an SCTP packet, consisting of 685 * a chunk header and chunk-specific content. 686 * 687 * As a matter of convenience, we remember the SCTP common header for 688 * each chunk as well as a few other header pointers... 689 */ 690 struct sctp_chunk { 691 struct list_head list; 692 693 atomic_t refcnt; 694 695 /* This is our link to the per-transport transmitted list. */ 696 struct list_head transmitted_list; 697 698 /* This field is used by chunks that hold fragmented data. 699 * For the first fragment this is the list that holds the rest of 700 * fragments. For the remaining fragments, this is the link to the 701 * frag_list maintained in the first fragment. 702 */ 703 struct list_head frag_list; 704 705 /* This points to the sk_buff containing the actual data. */ 706 struct sk_buff *skb; 707 708 /* These are the SCTP headers by reverse order in a packet. 709 * Note that some of these may happen more than once. In that 710 * case, we point at the "current" one, whatever that means 711 * for that level of header. 712 */ 713 714 /* We point this at the FIRST TLV parameter to chunk_hdr. */ 715 union sctp_params param_hdr; 716 union { 717 __u8 *v; 718 struct sctp_datahdr *data_hdr; 719 struct sctp_inithdr *init_hdr; 720 struct sctp_sackhdr *sack_hdr; 721 struct sctp_heartbeathdr *hb_hdr; 722 struct sctp_sender_hb_info *hbs_hdr; 723 struct sctp_shutdownhdr *shutdown_hdr; 724 struct sctp_signed_cookie *cookie_hdr; 725 struct sctp_ecnehdr *ecne_hdr; 726 struct sctp_cwrhdr *ecn_cwr_hdr; 727 struct sctp_errhdr *err_hdr; 728 struct sctp_addiphdr *addip_hdr; 729 struct sctp_fwdtsn_hdr *fwdtsn_hdr; 730 struct sctp_authhdr *auth_hdr; 731 } subh; 732 733 __u8 *chunk_end; 734 735 struct sctp_chunkhdr *chunk_hdr; 736 struct sctphdr *sctp_hdr; 737 738 /* This needs to be recoverable for SCTP_SEND_FAILED events. */ 739 struct sctp_sndrcvinfo sinfo; 740 741 /* Which association does this belong to? */ 742 struct sctp_association *asoc; 743 744 /* What endpoint received this chunk? */ 745 struct sctp_ep_common *rcvr; 746 747 /* We fill this in if we are calculating RTT. */ 748 unsigned long sent_at; 749 750 /* What is the origin IP address for this chunk? */ 751 union sctp_addr source; 752 /* Destination address for this chunk. */ 753 union sctp_addr dest; 754 755 /* For outbound message, track all fragments for SEND_FAILED. */ 756 struct sctp_datamsg *msg; 757 758 /* For an inbound chunk, this tells us where it came from. 759 * For an outbound chunk, it tells us where we'd like it to 760 * go. It is NULL if we have no preference. 761 */ 762 struct sctp_transport *transport; 763 764 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO 765 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH 766 * spec violates the principle premis that all chunks are processed 767 * in order. 768 */ 769 struct sk_buff *auth_chunk; 770 771 #define SCTP_CAN_FRTX 0x0 772 #define SCTP_NEED_FRTX 0x1 773 #define SCTP_DONT_FRTX 0x2 774 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */ 775 has_tsn:1, /* Does this chunk have a TSN yet? */ 776 has_ssn:1, /* Does this chunk have a SSN yet? */ 777 singleton:1, /* Only chunk in the packet? */ 778 end_of_packet:1, /* Last chunk in the packet? */ 779 ecn_ce_done:1, /* Have we processed the ECN CE bit? */ 780 pdiscard:1, /* Discard the whole packet now? */ 781 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */ 782 data_accepted:1, /* At least 1 chunk accepted */ 783 auth:1, /* IN: was auth'ed | OUT: needs auth */ 784 has_asconf:1, /* IN: have seen an asconf before */ 785 tsn_missing_report:2, /* Data chunk missing counter. */ 786 fast_retransmit:2; /* Is this chunk fast retransmitted? */ 787 }; 788 789 void sctp_chunk_hold(struct sctp_chunk *); 790 void sctp_chunk_put(struct sctp_chunk *); 791 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len, 792 struct iovec *data); 793 void sctp_chunk_free(struct sctp_chunk *); 794 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data); 795 void *sctp_addto_chunk_fixed(struct sctp_chunk *, int len, const void *data); 796 struct sctp_chunk *sctp_chunkify(struct sk_buff *, 797 const struct sctp_association *, 798 struct sock *); 799 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *, 800 union sctp_addr *); 801 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk); 802 803 enum { 804 SCTP_ADDR_NEW, /* new address added to assoc/ep */ 805 SCTP_ADDR_SRC, /* address can be used as source */ 806 SCTP_ADDR_DEL, /* address about to be deleted */ 807 }; 808 809 /* This is a structure for holding either an IPv6 or an IPv4 address. */ 810 struct sctp_sockaddr_entry { 811 struct list_head list; 812 struct rcu_head rcu; 813 union sctp_addr a; 814 __u8 state; 815 __u8 valid; 816 }; 817 818 #define SCTP_ADDRESS_TICK_DELAY 500 819 820 typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *); 821 822 /* This structure holds lists of chunks as we are assembling for 823 * transmission. 824 */ 825 struct sctp_packet { 826 /* These are the SCTP header values (host order) for the packet. */ 827 __u16 source_port; 828 __u16 destination_port; 829 __u32 vtag; 830 831 /* This contains the payload chunks. */ 832 struct list_head chunk_list; 833 834 /* This is the overhead of the sctp and ip headers. */ 835 size_t overhead; 836 /* This is the total size of all chunks INCLUDING padding. */ 837 size_t size; 838 839 /* The packet is destined for this transport address. 840 * The function we finally use to pass down to the next lower 841 * layer lives in the transport structure. 842 */ 843 struct sctp_transport *transport; 844 845 /* pointer to the auth chunk for this packet */ 846 struct sctp_chunk *auth; 847 848 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */ 849 has_sack:1, /* This packet contains a SACK chunk. */ 850 has_auth:1, /* This packet contains an AUTH chunk */ 851 has_data:1, /* This packet contains at least 1 DATA chunk */ 852 ipfragok:1, /* So let ip fragment this packet */ 853 malloced:1; /* Is it malloced? */ 854 }; 855 856 struct sctp_packet *sctp_packet_init(struct sctp_packet *, 857 struct sctp_transport *, 858 __u16 sport, __u16 dport); 859 struct sctp_packet *sctp_packet_config(struct sctp_packet *, __u32 vtag, int); 860 sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *, 861 struct sctp_chunk *, int); 862 sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *, 863 struct sctp_chunk *); 864 int sctp_packet_transmit(struct sctp_packet *); 865 void sctp_packet_free(struct sctp_packet *); 866 867 static inline int sctp_packet_empty(struct sctp_packet *packet) 868 { 869 return packet->size == packet->overhead; 870 } 871 872 /* This represents a remote transport address. 873 * For local transport addresses, we just use union sctp_addr. 874 * 875 * RFC2960 Section 1.4 Key Terms 876 * 877 * o Transport address: A Transport Address is traditionally defined 878 * by Network Layer address, Transport Layer protocol and Transport 879 * Layer port number. In the case of SCTP running over IP, a 880 * transport address is defined by the combination of an IP address 881 * and an SCTP port number (where SCTP is the Transport protocol). 882 * 883 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control 884 * 885 * o The sender keeps a separate congestion control parameter set for 886 * each of the destination addresses it can send to (not each 887 * source-destination pair but for each destination). The parameters 888 * should decay if the address is not used for a long enough time 889 * period. 890 * 891 */ 892 struct sctp_transport { 893 /* A list of transports. */ 894 struct list_head transports; 895 896 /* Reference counting. */ 897 atomic_t refcnt; 898 __u32 dead:1, 899 /* RTO-Pending : A flag used to track if one of the DATA 900 * chunks sent to this address is currently being 901 * used to compute a RTT. If this flag is 0, 902 * the next DATA chunk sent to this destination 903 * should be used to compute a RTT and this flag 904 * should be set. Every time the RTT 905 * calculation completes (i.e. the DATA chunk 906 * is SACK'd) clear this flag. 907 */ 908 rto_pending:1, 909 910 /* 911 * hb_sent : a flag that signals that we have a pending 912 * heartbeat. 913 */ 914 hb_sent:1, 915 916 /* Is the Path MTU update pending on this tranport */ 917 pmtu_pending:1, 918 919 /* Is this structure kfree()able? */ 920 malloced:1; 921 922 /* Has this transport moved the ctsn since we last sacked */ 923 __u32 sack_generation; 924 925 struct flowi fl; 926 927 /* This is the peer's IP address and port. */ 928 union sctp_addr ipaddr; 929 930 /* These are the functions we call to handle LLP stuff. */ 931 struct sctp_af *af_specific; 932 933 /* Which association do we belong to? */ 934 struct sctp_association *asoc; 935 936 /* RFC2960 937 * 938 * 12.3 Per Transport Address Data 939 * 940 * For each destination transport address in the peer's 941 * address list derived from the INIT or INIT ACK chunk, a 942 * number of data elements needs to be maintained including: 943 */ 944 /* RTO : The current retransmission timeout value. */ 945 unsigned long rto; 946 947 __u32 rtt; /* This is the most recent RTT. */ 948 949 /* RTTVAR : The current RTT variation. */ 950 __u32 rttvar; 951 952 /* SRTT : The current smoothed round trip time. */ 953 __u32 srtt; 954 955 /* 956 * These are the congestion stats. 957 */ 958 /* cwnd : The current congestion window. */ 959 __u32 cwnd; /* This is the actual cwnd. */ 960 961 /* ssthresh : The current slow start threshold value. */ 962 __u32 ssthresh; 963 964 /* partial : The tracking method for increase of cwnd when in 965 * bytes acked : congestion avoidance mode (see Section 6.2.2) 966 */ 967 __u32 partial_bytes_acked; 968 969 /* Data that has been sent, but not acknowledged. */ 970 __u32 flight_size; 971 972 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */ 973 974 /* Destination */ 975 struct dst_entry *dst; 976 /* Source address. */ 977 union sctp_addr saddr; 978 979 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 980 * the destination address every heartbeat interval. 981 */ 982 unsigned long hbinterval; 983 984 /* SACK delay timeout */ 985 unsigned long sackdelay; 986 __u32 sackfreq; 987 988 /* When was the last time (in jiffies) that we heard from this 989 * transport? We use this to pick new active and retran paths. 990 */ 991 unsigned long last_time_heard; 992 993 /* Last time(in jiffies) when cwnd is reduced due to the congestion 994 * indication based on ECNE chunk. 995 */ 996 unsigned long last_time_ecne_reduced; 997 998 /* This is the max_retrans value for the transport and will 999 * be initialized from the assocs value. This can be changed 1000 * using the SCTP_SET_PEER_ADDR_PARAMS socket option. 1001 */ 1002 __u16 pathmaxrxt; 1003 1004 /* This is the partially failed retrans value for the transport 1005 * and will be initialized from the assocs value. This can be changed 1006 * using the SCTP_PEER_ADDR_THLDS socket option 1007 */ 1008 int pf_retrans; 1009 /* PMTU : The current known path MTU. */ 1010 __u32 pathmtu; 1011 1012 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 1013 __u32 param_flags; 1014 1015 /* The number of times INIT has been sent on this transport. */ 1016 int init_sent_count; 1017 1018 /* state : The current state of this destination, 1019 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN. 1020 */ 1021 int state; 1022 1023 /* These are the error stats for this destination. */ 1024 1025 /* Error count : The current error count for this destination. */ 1026 unsigned short error_count; 1027 1028 /* Per : A timer used by each destination. 1029 * Destination : 1030 * Timer : 1031 * 1032 * [Everywhere else in the text this is called T3-rtx. -ed] 1033 */ 1034 struct timer_list T3_rtx_timer; 1035 1036 /* Heartbeat timer is per destination. */ 1037 struct timer_list hb_timer; 1038 1039 /* Timer to handle ICMP proto unreachable envets */ 1040 struct timer_list proto_unreach_timer; 1041 1042 /* Since we're using per-destination retransmission timers 1043 * (see above), we're also using per-destination "transmitted" 1044 * queues. This probably ought to be a private struct 1045 * accessible only within the outqueue, but it's not, yet. 1046 */ 1047 struct list_head transmitted; 1048 1049 /* We build bundle-able packets for this transport here. */ 1050 struct sctp_packet packet; 1051 1052 /* This is the list of transports that have chunks to send. */ 1053 struct list_head send_ready; 1054 1055 /* State information saved for SFR_CACC algorithm. The key 1056 * idea in SFR_CACC is to maintain state at the sender on a 1057 * per-destination basis when a changeover happens. 1058 * char changeover_active; 1059 * char cycling_changeover; 1060 * __u32 next_tsn_at_change; 1061 * char cacc_saw_newack; 1062 */ 1063 struct { 1064 /* An unsigned integer, which stores the next TSN to be 1065 * used by the sender, at the moment of changeover. 1066 */ 1067 __u32 next_tsn_at_change; 1068 1069 /* A flag which indicates the occurrence of a changeover */ 1070 char changeover_active; 1071 1072 /* A flag which indicates whether the change of primary is 1073 * the first switch to this destination address during an 1074 * active switch. 1075 */ 1076 char cycling_changeover; 1077 1078 /* A temporary flag, which is used during the processing of 1079 * a SACK to estimate the causative TSN(s)'s group. 1080 */ 1081 char cacc_saw_newack; 1082 } cacc; 1083 1084 /* 64-bit random number sent with heartbeat. */ 1085 __u64 hb_nonce; 1086 }; 1087 1088 struct sctp_transport *sctp_transport_new(const union sctp_addr *, 1089 gfp_t); 1090 void sctp_transport_set_owner(struct sctp_transport *, 1091 struct sctp_association *); 1092 void sctp_transport_route(struct sctp_transport *, union sctp_addr *, 1093 struct sctp_sock *); 1094 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk); 1095 void sctp_transport_free(struct sctp_transport *); 1096 void sctp_transport_reset_timers(struct sctp_transport *); 1097 void sctp_transport_hold(struct sctp_transport *); 1098 void sctp_transport_put(struct sctp_transport *); 1099 void sctp_transport_update_rto(struct sctp_transport *, __u32); 1100 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32); 1101 void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t); 1102 void sctp_transport_burst_limited(struct sctp_transport *); 1103 void sctp_transport_burst_reset(struct sctp_transport *); 1104 unsigned long sctp_transport_timeout(struct sctp_transport *); 1105 void sctp_transport_reset(struct sctp_transport *); 1106 void sctp_transport_update_pmtu(struct sock *, struct sctp_transport *, u32); 1107 void sctp_transport_immediate_rtx(struct sctp_transport *); 1108 1109 1110 /* This is the structure we use to queue packets as they come into 1111 * SCTP. We write packets to it and read chunks from it. 1112 */ 1113 struct sctp_inq { 1114 /* This is actually a queue of sctp_chunk each 1115 * containing a partially decoded packet. 1116 */ 1117 struct list_head in_chunk_list; 1118 /* This is the packet which is currently off the in queue and is 1119 * being worked on through the inbound chunk processing. 1120 */ 1121 struct sctp_chunk *in_progress; 1122 1123 /* This is the delayed task to finish delivering inbound 1124 * messages. 1125 */ 1126 struct work_struct immediate; 1127 1128 int malloced; /* Is this structure kfree()able? */ 1129 }; 1130 1131 void sctp_inq_init(struct sctp_inq *); 1132 void sctp_inq_free(struct sctp_inq *); 1133 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet); 1134 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *); 1135 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *); 1136 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t); 1137 1138 /* This is the structure we use to hold outbound chunks. You push 1139 * chunks in and they automatically pop out the other end as bundled 1140 * packets (it calls (*output_handler)()). 1141 * 1142 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1, 1143 * and 8.2 of the v13 draft. 1144 * 1145 * It handles retransmissions. The connection to the timeout portion 1146 * of the state machine is through sctp_..._timeout() and timeout_handler. 1147 * 1148 * If you feed it SACKs, it will eat them. 1149 * 1150 * If you give it big chunks, it will fragment them. 1151 * 1152 * It assigns TSN's to data chunks. This happens at the last possible 1153 * instant before transmission. 1154 * 1155 * When free()'d, it empties itself out via output_handler(). 1156 */ 1157 struct sctp_outq { 1158 struct sctp_association *asoc; 1159 1160 /* Data pending that has never been transmitted. */ 1161 struct list_head out_chunk_list; 1162 1163 unsigned int out_qlen; /* Total length of queued data chunks. */ 1164 1165 /* Error of send failed, may used in SCTP_SEND_FAILED event. */ 1166 unsigned int error; 1167 1168 /* These are control chunks we want to send. */ 1169 struct list_head control_chunk_list; 1170 1171 /* These are chunks that have been sacked but are above the 1172 * CTSN, or cumulative tsn ack point. 1173 */ 1174 struct list_head sacked; 1175 1176 /* Put chunks on this list to schedule them for 1177 * retransmission. 1178 */ 1179 struct list_head retransmit; 1180 1181 /* Put chunks on this list to save them for FWD TSN processing as 1182 * they were abandoned. 1183 */ 1184 struct list_head abandoned; 1185 1186 /* How many unackd bytes do we have in-flight? */ 1187 __u32 outstanding_bytes; 1188 1189 /* Are we doing fast-rtx on this queue */ 1190 char fast_rtx; 1191 1192 /* Corked? */ 1193 char cork; 1194 1195 /* Is this structure empty? */ 1196 char empty; 1197 1198 /* Are we kfree()able? */ 1199 char malloced; 1200 }; 1201 1202 void sctp_outq_init(struct sctp_association *, struct sctp_outq *); 1203 void sctp_outq_teardown(struct sctp_outq *); 1204 void sctp_outq_free(struct sctp_outq*); 1205 int sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk); 1206 int sctp_outq_sack(struct sctp_outq *, struct sctp_sackhdr *); 1207 int sctp_outq_is_empty(const struct sctp_outq *); 1208 void sctp_outq_restart(struct sctp_outq *); 1209 1210 void sctp_retransmit(struct sctp_outq *, struct sctp_transport *, 1211 sctp_retransmit_reason_t); 1212 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8); 1213 int sctp_outq_uncork(struct sctp_outq *); 1214 /* Uncork and flush an outqueue. */ 1215 static inline void sctp_outq_cork(struct sctp_outq *q) 1216 { 1217 q->cork = 1; 1218 } 1219 1220 /* These bind address data fields common between endpoints and associations */ 1221 struct sctp_bind_addr { 1222 1223 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1224 * 1225 * SCTP Port: The local SCTP port number the endpoint is 1226 * bound to. 1227 */ 1228 __u16 port; 1229 1230 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1231 * 1232 * Address List: The list of IP addresses that this instance 1233 * has bound. This information is passed to one's 1234 * peer(s) in INIT and INIT ACK chunks. 1235 */ 1236 struct list_head address_list; 1237 1238 int malloced; /* Are we kfree()able? */ 1239 }; 1240 1241 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port); 1242 void sctp_bind_addr_free(struct sctp_bind_addr *); 1243 int sctp_bind_addr_copy(struct sctp_bind_addr *dest, 1244 const struct sctp_bind_addr *src, 1245 sctp_scope_t scope, gfp_t gfp, 1246 int flags); 1247 int sctp_bind_addr_dup(struct sctp_bind_addr *dest, 1248 const struct sctp_bind_addr *src, 1249 gfp_t gfp); 1250 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *, 1251 __u8 addr_state, gfp_t gfp); 1252 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *); 1253 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *, 1254 struct sctp_sock *); 1255 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *, 1256 struct sctp_sock *, struct sctp_sock *); 1257 int sctp_bind_addr_state(const struct sctp_bind_addr *bp, 1258 const union sctp_addr *addr); 1259 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp, 1260 const union sctp_addr *addrs, 1261 int addrcnt, 1262 struct sctp_sock *opt); 1263 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp, 1264 int *addrs_len, 1265 gfp_t gfp); 1266 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len, 1267 __u16 port, gfp_t gfp); 1268 1269 sctp_scope_t sctp_scope(const union sctp_addr *); 1270 int sctp_in_scope(const union sctp_addr *addr, const sctp_scope_t scope); 1271 int sctp_is_any(struct sock *sk, const union sctp_addr *addr); 1272 int sctp_addr_is_valid(const union sctp_addr *addr); 1273 int sctp_is_ep_boundall(struct sock *sk); 1274 1275 1276 /* What type of endpoint? */ 1277 typedef enum { 1278 SCTP_EP_TYPE_SOCKET, 1279 SCTP_EP_TYPE_ASSOCIATION, 1280 } sctp_endpoint_type_t; 1281 1282 /* 1283 * A common base class to bridge the implmentation view of a 1284 * socket (usually listening) endpoint versus an association's 1285 * local endpoint. 1286 * This common structure is useful for several purposes: 1287 * 1) Common interface for lookup routines. 1288 * a) Subfunctions work for either endpoint or association 1289 * b) Single interface to lookup allows hiding the lookup lock rather 1290 * than acquiring it externally. 1291 * 2) Common interface for the inbound chunk handling/state machine. 1292 * 3) Common object handling routines for reference counting, etc. 1293 * 4) Disentangle association lookup from endpoint lookup, where we 1294 * do not have to find our endpoint to find our association. 1295 * 1296 */ 1297 1298 struct sctp_ep_common { 1299 /* Fields to help us manage our entries in the hash tables. */ 1300 struct hlist_node node; 1301 int hashent; 1302 1303 /* Runtime type information. What kind of endpoint is this? */ 1304 sctp_endpoint_type_t type; 1305 1306 /* Some fields to help us manage this object. 1307 * refcnt - Reference count access to this object. 1308 * dead - Do not attempt to use this object. 1309 * malloced - Do we need to kfree this object? 1310 */ 1311 atomic_t refcnt; 1312 char dead; 1313 char malloced; 1314 1315 /* What socket does this endpoint belong to? */ 1316 struct sock *sk; 1317 1318 /* This is where we receive inbound chunks. */ 1319 struct sctp_inq inqueue; 1320 1321 /* This substructure includes the defining parameters of the 1322 * endpoint: 1323 * bind_addr.port is our shared port number. 1324 * bind_addr.address_list is our set of local IP addresses. 1325 */ 1326 struct sctp_bind_addr bind_addr; 1327 }; 1328 1329 1330 /* RFC Section 1.4 Key Terms 1331 * 1332 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a 1333 * multi-homed host, an SCTP endpoint is represented to its peers as a 1334 * combination of a set of eligible destination transport addresses to 1335 * which SCTP packets can be sent and a set of eligible source 1336 * transport addresses from which SCTP packets can be received. 1337 * All transport addresses used by an SCTP endpoint must use the 1338 * same port number, but can use multiple IP addresses. A transport 1339 * address used by an SCTP endpoint must not be used by another 1340 * SCTP endpoint. In other words, a transport address is unique 1341 * to an SCTP endpoint. 1342 * 1343 * From an implementation perspective, each socket has one of these. 1344 * A TCP-style socket will have exactly one association on one of 1345 * these. An UDP-style socket will have multiple associations hanging 1346 * off one of these. 1347 */ 1348 1349 struct sctp_endpoint { 1350 /* Common substructure for endpoint and association. */ 1351 struct sctp_ep_common base; 1352 1353 /* Associations: A list of current associations and mappings 1354 * to the data consumers for each association. This 1355 * may be in the form of a hash table or other 1356 * implementation dependent structure. The data 1357 * consumers may be process identification 1358 * information such as file descriptors, named pipe 1359 * pointer, or table pointers dependent on how SCTP 1360 * is implemented. 1361 */ 1362 /* This is really a list of struct sctp_association entries. */ 1363 struct list_head asocs; 1364 1365 /* Secret Key: A secret key used by this endpoint to compute 1366 * the MAC. This SHOULD be a cryptographic quality 1367 * random number with a sufficient length. 1368 * Discussion in [RFC1750] can be helpful in 1369 * selection of the key. 1370 */ 1371 __u8 secret_key[SCTP_HOW_MANY_SECRETS][SCTP_SECRET_SIZE]; 1372 int current_key; 1373 int last_key; 1374 int key_changed_at; 1375 1376 /* digest: This is a digest of the sctp cookie. This field is 1377 * only used on the receive path when we try to validate 1378 * that the cookie has not been tampered with. We put 1379 * this here so we pre-allocate this once and can re-use 1380 * on every receive. 1381 */ 1382 __u8 *digest; 1383 1384 /* sendbuf acct. policy. */ 1385 __u32 sndbuf_policy; 1386 1387 /* rcvbuf acct. policy. */ 1388 __u32 rcvbuf_policy; 1389 1390 /* SCTP AUTH: array of the HMACs that will be allocated 1391 * we need this per association so that we don't serialize 1392 */ 1393 struct crypto_hash **auth_hmacs; 1394 1395 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */ 1396 struct sctp_hmac_algo_param *auth_hmacs_list; 1397 1398 /* SCTP-AUTH: chunks to authenticate encoded into parameter */ 1399 struct sctp_chunks_param *auth_chunk_list; 1400 1401 /* SCTP-AUTH: endpoint shared keys */ 1402 struct list_head endpoint_shared_keys; 1403 __u16 active_key_id; 1404 }; 1405 1406 /* Recover the outter endpoint structure. */ 1407 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base) 1408 { 1409 struct sctp_endpoint *ep; 1410 1411 ep = container_of(base, struct sctp_endpoint, base); 1412 return ep; 1413 } 1414 1415 /* These are function signatures for manipulating endpoints. */ 1416 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t); 1417 void sctp_endpoint_free(struct sctp_endpoint *); 1418 void sctp_endpoint_put(struct sctp_endpoint *); 1419 void sctp_endpoint_hold(struct sctp_endpoint *); 1420 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *); 1421 struct sctp_association *sctp_endpoint_lookup_assoc( 1422 const struct sctp_endpoint *ep, 1423 const union sctp_addr *paddr, 1424 struct sctp_transport **); 1425 int sctp_endpoint_is_peeled_off(struct sctp_endpoint *, 1426 const union sctp_addr *); 1427 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *, 1428 const union sctp_addr *); 1429 int sctp_has_association(const union sctp_addr *laddr, 1430 const union sctp_addr *paddr); 1431 1432 int sctp_verify_init(const struct sctp_association *asoc, sctp_cid_t, 1433 sctp_init_chunk_t *peer_init, struct sctp_chunk *chunk, 1434 struct sctp_chunk **err_chunk); 1435 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk, 1436 const union sctp_addr *peer, 1437 sctp_init_chunk_t *init, gfp_t gfp); 1438 __u32 sctp_generate_tag(const struct sctp_endpoint *); 1439 __u32 sctp_generate_tsn(const struct sctp_endpoint *); 1440 1441 struct sctp_inithdr_host { 1442 __u32 init_tag; 1443 __u32 a_rwnd; 1444 __u16 num_outbound_streams; 1445 __u16 num_inbound_streams; 1446 __u32 initial_tsn; 1447 }; 1448 1449 /* RFC2960 1450 * 1451 * 12. Recommended Transmission Control Block (TCB) Parameters 1452 * 1453 * This section details a recommended set of parameters that should 1454 * be contained within the TCB for an implementation. This section is 1455 * for illustrative purposes and should not be deemed as requirements 1456 * on an implementation or as an exhaustive list of all parameters 1457 * inside an SCTP TCB. Each implementation may need its own additional 1458 * parameters for optimization. 1459 */ 1460 1461 1462 /* Here we have information about each individual association. */ 1463 struct sctp_association { 1464 1465 /* A base structure common to endpoint and association. 1466 * In this context, it represents the associations's view 1467 * of the local endpoint of the association. 1468 */ 1469 struct sctp_ep_common base; 1470 1471 /* Associations on the same socket. */ 1472 struct list_head asocs; 1473 1474 /* association id. */ 1475 sctp_assoc_t assoc_id; 1476 1477 /* This is our parent endpoint. */ 1478 struct sctp_endpoint *ep; 1479 1480 /* These are those association elements needed in the cookie. */ 1481 struct sctp_cookie c; 1482 1483 /* This is all information about our peer. */ 1484 struct { 1485 /* rwnd 1486 * 1487 * Peer Rwnd : Current calculated value of the peer's rwnd. 1488 */ 1489 __u32 rwnd; 1490 1491 /* transport_addr_list 1492 * 1493 * Peer : A list of SCTP transport addresses that the 1494 * Transport : peer is bound to. This information is derived 1495 * Address : from the INIT or INIT ACK and is used to 1496 * List : associate an inbound packet with a given 1497 * : association. Normally this information is 1498 * : hashed or keyed for quick lookup and access 1499 * : of the TCB. 1500 * : The list is also initialized with the list 1501 * : of addresses passed with the sctp_connectx() 1502 * : call. 1503 * 1504 * It is a list of SCTP_transport's. 1505 */ 1506 struct list_head transport_addr_list; 1507 1508 /* transport_count 1509 * 1510 * Peer : A count of the number of peer addresses 1511 * Transport : in the Peer Transport Address List. 1512 * Address : 1513 * Count : 1514 */ 1515 __u16 transport_count; 1516 1517 /* port 1518 * The transport layer port number. 1519 */ 1520 __u16 port; 1521 1522 /* primary_path 1523 * 1524 * Primary : This is the current primary destination 1525 * Path : transport address of the peer endpoint. It 1526 * : may also specify a source transport address 1527 * : on this endpoint. 1528 * 1529 * All of these paths live on transport_addr_list. 1530 * 1531 * At the bakeoffs, we discovered that the intent of 1532 * primaryPath is that it only changes when the ULP 1533 * asks to have it changed. We add the activePath to 1534 * designate the connection we are currently using to 1535 * transmit new data and most control chunks. 1536 */ 1537 struct sctp_transport *primary_path; 1538 1539 /* Cache the primary path address here, when we 1540 * need a an address for msg_name. 1541 */ 1542 union sctp_addr primary_addr; 1543 1544 /* active_path 1545 * The path that we are currently using to 1546 * transmit new data and most control chunks. 1547 */ 1548 struct sctp_transport *active_path; 1549 1550 /* retran_path 1551 * 1552 * RFC2960 6.4 Multi-homed SCTP Endpoints 1553 * ... 1554 * Furthermore, when its peer is multi-homed, an 1555 * endpoint SHOULD try to retransmit a chunk to an 1556 * active destination transport address that is 1557 * different from the last destination address to 1558 * which the DATA chunk was sent. 1559 */ 1560 struct sctp_transport *retran_path; 1561 1562 /* Pointer to last transport I have sent on. */ 1563 struct sctp_transport *last_sent_to; 1564 1565 /* This is the last transport I have received DATA on. */ 1566 struct sctp_transport *last_data_from; 1567 1568 /* 1569 * Mapping An array of bits or bytes indicating which out of 1570 * Array order TSN's have been received (relative to the 1571 * Last Rcvd TSN). If no gaps exist, i.e. no out of 1572 * order packets have been received, this array 1573 * will be set to all zero. This structure may be 1574 * in the form of a circular buffer or bit array. 1575 * 1576 * Last Rcvd : This is the last TSN received in 1577 * TSN : sequence. This value is set initially by 1578 * : taking the peer's Initial TSN, received in 1579 * : the INIT or INIT ACK chunk, and subtracting 1580 * : one from it. 1581 * 1582 * Throughout most of the specification this is called the 1583 * "Cumulative TSN ACK Point". In this case, we 1584 * ignore the advice in 12.2 in favour of the term 1585 * used in the bulk of the text. This value is hidden 1586 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn(). 1587 */ 1588 struct sctp_tsnmap tsn_map; 1589 1590 /* Ack State : This flag indicates if the next received 1591 * : packet is to be responded to with a 1592 * : SACK. This is initializedto 0. When a packet 1593 * : is received it is incremented. If this value 1594 * : reaches 2 or more, a SACK is sent and the 1595 * : value is reset to 0. Note: This is used only 1596 * : when no DATA chunks are received out of 1597 * : order. When DATA chunks are out of order, 1598 * : SACK's are not delayed (see Section 6). 1599 */ 1600 __u8 sack_needed; /* Do we need to sack the peer? */ 1601 __u32 sack_cnt; 1602 __u32 sack_generation; 1603 1604 /* These are capabilities which our peer advertised. */ 1605 __u8 ecn_capable:1, /* Can peer do ECN? */ 1606 ipv4_address:1, /* Peer understands IPv4 addresses? */ 1607 ipv6_address:1, /* Peer understands IPv6 addresses? */ 1608 hostname_address:1, /* Peer understands DNS addresses? */ 1609 asconf_capable:1, /* Does peer support ADDIP? */ 1610 prsctp_capable:1, /* Can peer do PR-SCTP? */ 1611 auth_capable:1; /* Is peer doing SCTP-AUTH? */ 1612 1613 __u32 adaptation_ind; /* Adaptation Code point. */ 1614 1615 /* This mask is used to disable sending the ASCONF chunk 1616 * with specified parameter to peer. 1617 */ 1618 __be16 addip_disabled_mask; 1619 1620 struct sctp_inithdr_host i; 1621 int cookie_len; 1622 void *cookie; 1623 1624 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. 1625 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the 1626 * Initial TSN Value minus 1 1627 */ 1628 __u32 addip_serial; 1629 1630 /* SCTP-AUTH: We need to know pears random number, hmac list 1631 * and authenticated chunk list. All that is part of the 1632 * cookie and these are just pointers to those locations 1633 */ 1634 sctp_random_param_t *peer_random; 1635 sctp_chunks_param_t *peer_chunks; 1636 sctp_hmac_algo_param_t *peer_hmacs; 1637 } peer; 1638 1639 /* State : A state variable indicating what state the 1640 * : association is in, i.e. COOKIE-WAIT, 1641 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING, 1642 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT. 1643 * 1644 * Note: No "CLOSED" state is illustrated since if a 1645 * association is "CLOSED" its TCB SHOULD be removed. 1646 * 1647 * In this implementation we DO have a CLOSED 1648 * state which is used during initiation and shutdown. 1649 * 1650 * State takes values from SCTP_STATE_*. 1651 */ 1652 sctp_state_t state; 1653 1654 /* The cookie life I award for any cookie. */ 1655 struct timeval cookie_life; 1656 1657 /* Overall : The overall association error count. 1658 * Error Count : [Clear this any time I get something.] 1659 */ 1660 int overall_error_count; 1661 1662 /* These are the association's initial, max, and min RTO values. 1663 * These values will be initialized by system defaults, but can 1664 * be modified via the SCTP_RTOINFO socket option. 1665 */ 1666 unsigned long rto_initial; 1667 unsigned long rto_max; 1668 unsigned long rto_min; 1669 1670 /* Maximum number of new data packets that can be sent in a burst. */ 1671 int max_burst; 1672 1673 /* This is the max_retrans value for the association. This value will 1674 * be initialized initialized from system defaults, but can be 1675 * modified by the SCTP_ASSOCINFO socket option. 1676 */ 1677 int max_retrans; 1678 1679 /* This is the partially failed retrans value for the transport 1680 * and will be initialized from the assocs value. This can be 1681 * changed using the SCTP_PEER_ADDR_THLDS socket option 1682 */ 1683 int pf_retrans; 1684 1685 /* Maximum number of times the endpoint will retransmit INIT */ 1686 __u16 max_init_attempts; 1687 1688 /* How many times have we resent an INIT? */ 1689 __u16 init_retries; 1690 1691 /* The largest timeout or RTO value to use in attempting an INIT */ 1692 unsigned long max_init_timeo; 1693 1694 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 1695 * the destination address every heartbeat interval. This value 1696 * will be inherited by all new transports. 1697 */ 1698 unsigned long hbinterval; 1699 1700 /* This is the max_retrans value for new transports in the 1701 * association. 1702 */ 1703 __u16 pathmaxrxt; 1704 1705 /* Flag that path mtu update is pending */ 1706 __u8 pmtu_pending; 1707 1708 /* Association : The smallest PMTU discovered for all of the 1709 * PMTU : peer's transport addresses. 1710 */ 1711 __u32 pathmtu; 1712 1713 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 1714 __u32 param_flags; 1715 1716 /* SACK delay timeout */ 1717 unsigned long sackdelay; 1718 __u32 sackfreq; 1719 1720 1721 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES]; 1722 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES]; 1723 1724 /* Transport to which SHUTDOWN chunk was last sent. */ 1725 struct sctp_transport *shutdown_last_sent_to; 1726 1727 /* How many times have we resent a SHUTDOWN */ 1728 int shutdown_retries; 1729 1730 /* Transport to which INIT chunk was last sent. */ 1731 struct sctp_transport *init_last_sent_to; 1732 1733 /* Next TSN : The next TSN number to be assigned to a new 1734 * : DATA chunk. This is sent in the INIT or INIT 1735 * : ACK chunk to the peer and incremented each 1736 * : time a DATA chunk is assigned a TSN 1737 * : (normally just prior to transmit or during 1738 * : fragmentation). 1739 */ 1740 __u32 next_tsn; 1741 1742 /* 1743 * Last Rcvd : This is the last TSN received in sequence. This value 1744 * TSN : is set initially by taking the peer's Initial TSN, 1745 * : received in the INIT or INIT ACK chunk, and 1746 * : subtracting one from it. 1747 * 1748 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point. 1749 */ 1750 1751 __u32 ctsn_ack_point; 1752 1753 /* PR-SCTP Advanced.Peer.Ack.Point */ 1754 __u32 adv_peer_ack_point; 1755 1756 /* Highest TSN that is acknowledged by incoming SACKs. */ 1757 __u32 highest_sacked; 1758 1759 /* TSN marking the fast recovery exit point */ 1760 __u32 fast_recovery_exit; 1761 1762 /* Flag to track the current fast recovery state */ 1763 __u8 fast_recovery; 1764 1765 /* The number of unacknowledged data chunks. Reported through 1766 * the SCTP_STATUS sockopt. 1767 */ 1768 __u16 unack_data; 1769 1770 /* The total number of data chunks that we've had to retransmit 1771 * as the result of a T3 timer expiration 1772 */ 1773 __u32 rtx_data_chunks; 1774 1775 /* This is the association's receive buffer space. This value is used 1776 * to set a_rwnd field in an INIT or a SACK chunk. 1777 */ 1778 __u32 rwnd; 1779 1780 /* This is the last advertised value of rwnd over a SACK chunk. */ 1781 __u32 a_rwnd; 1782 1783 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed 1784 * to slop over a maximum of the association's frag_point. 1785 */ 1786 __u32 rwnd_over; 1787 1788 /* Keeps treack of rwnd pressure. This happens when we have 1789 * a window, but not recevie buffer (i.e small packets). This one 1790 * is releases slowly (1 PMTU at a time ). 1791 */ 1792 __u32 rwnd_press; 1793 1794 /* This is the sndbuf size in use for the association. 1795 * This corresponds to the sndbuf size for the association, 1796 * as specified in the sk->sndbuf. 1797 */ 1798 int sndbuf_used; 1799 1800 /* This is the amount of memory that this association has allocated 1801 * in the receive path at any given time. 1802 */ 1803 atomic_t rmem_alloc; 1804 1805 /* This is the wait queue head for send requests waiting on 1806 * the association sndbuf space. 1807 */ 1808 wait_queue_head_t wait; 1809 1810 /* The message size at which SCTP fragmentation will occur. */ 1811 __u32 frag_point; 1812 __u32 user_frag; 1813 1814 /* Counter used to count INIT errors. */ 1815 int init_err_counter; 1816 1817 /* Count the number of INIT cycles (for doubling timeout). */ 1818 int init_cycle; 1819 1820 /* Default send parameters. */ 1821 __u16 default_stream; 1822 __u16 default_flags; 1823 __u32 default_ppid; 1824 __u32 default_context; 1825 __u32 default_timetolive; 1826 1827 /* Default receive parameters */ 1828 __u32 default_rcv_context; 1829 1830 /* This tracks outbound ssn for a given stream. */ 1831 struct sctp_ssnmap *ssnmap; 1832 1833 /* All outbound chunks go through this structure. */ 1834 struct sctp_outq outqueue; 1835 1836 /* A smart pipe that will handle reordering and fragmentation, 1837 * as well as handle passing events up to the ULP. 1838 */ 1839 struct sctp_ulpq ulpq; 1840 1841 /* Last TSN that caused an ECNE Chunk to be sent. */ 1842 __u32 last_ecne_tsn; 1843 1844 /* Last TSN that caused a CWR Chunk to be sent. */ 1845 __u32 last_cwr_tsn; 1846 1847 /* How many duplicated TSNs have we seen? */ 1848 int numduptsns; 1849 1850 /* Number of seconds of idle time before an association is closed. 1851 * In the association context, this is really used as a boolean 1852 * since the real timeout is stored in the timeouts array 1853 */ 1854 __u32 autoclose; 1855 1856 /* These are to support 1857 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses 1858 * and Enforcement of Flow and Message Limits" 1859 * <draft-ietf-tsvwg-addip-sctp-02.txt> 1860 * or "ADDIP" for short. 1861 */ 1862 1863 1864 1865 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1866 * 1867 * R1) One and only one ASCONF Chunk MAY be in transit and 1868 * unacknowledged at any one time. If a sender, after sending 1869 * an ASCONF chunk, decides it needs to transfer another 1870 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1871 * returns from the previous ASCONF Chunk before sending a 1872 * subsequent ASCONF. Note this restriction binds each side, 1873 * so at any time two ASCONF may be in-transit on any given 1874 * association (one sent from each endpoint). 1875 * 1876 * [This is our one-and-only-one ASCONF in flight. If we do 1877 * not have an ASCONF in flight, this is NULL.] 1878 */ 1879 struct sctp_chunk *addip_last_asconf; 1880 1881 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk. 1882 * 1883 * This is needed to implement itmes E1 - E4 of the updated 1884 * spec. Here is the justification: 1885 * 1886 * Since the peer may bundle multiple ASCONF chunks toward us, 1887 * we now need the ability to cache multiple ACKs. The section 1888 * describes in detail how they are cached and cleaned up. 1889 */ 1890 struct list_head asconf_ack_list; 1891 1892 /* These ASCONF chunks are waiting to be sent. 1893 * 1894 * These chunaks can't be pushed to outqueue until receiving 1895 * ASCONF_ACK for the previous ASCONF indicated by 1896 * addip_last_asconf, so as to guarantee that only one ASCONF 1897 * is in flight at any time. 1898 * 1899 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1900 * 1901 * In defining the ASCONF Chunk transfer procedures, it is 1902 * essential that these transfers MUST NOT cause congestion 1903 * within the network. To achieve this, we place these 1904 * restrictions on the transfer of ASCONF Chunks: 1905 * 1906 * R1) One and only one ASCONF Chunk MAY be in transit and 1907 * unacknowledged at any one time. If a sender, after sending 1908 * an ASCONF chunk, decides it needs to transfer another 1909 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1910 * returns from the previous ASCONF Chunk before sending a 1911 * subsequent ASCONF. Note this restriction binds each side, 1912 * so at any time two ASCONF may be in-transit on any given 1913 * association (one sent from each endpoint). 1914 * 1915 * 1916 * [I really think this is EXACTLY the sort of intelligence 1917 * which already resides in sctp_outq. Please move this 1918 * queue and its supporting logic down there. --piggy] 1919 */ 1920 struct list_head addip_chunk_list; 1921 1922 /* ADDIP Section 4.1 ASCONF Chunk Procedures 1923 * 1924 * A2) A serial number should be assigned to the Chunk. The 1925 * serial number SHOULD be a monotonically increasing 1926 * number. The serial number SHOULD be initialized at 1927 * the start of the association to the same value as the 1928 * Initial TSN and every time a new ASCONF chunk is created 1929 * it is incremented by one after assigning the serial number 1930 * to the newly created chunk. 1931 * 1932 * ADDIP 1933 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF) 1934 * 1935 * Serial Number : 32 bits (unsigned integer) 1936 * 1937 * This value represents a Serial Number for the ASCONF 1938 * Chunk. The valid range of Serial Number is from 0 to 1939 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0 1940 * after reaching 4294967295. 1941 */ 1942 __u32 addip_serial; 1943 union sctp_addr *asconf_addr_del_pending; 1944 int src_out_of_asoc_ok; 1945 struct sctp_transport *new_transport; 1946 1947 /* SCTP AUTH: list of the endpoint shared keys. These 1948 * keys are provided out of band by the user applicaton 1949 * and can't change during the lifetime of the association 1950 */ 1951 struct list_head endpoint_shared_keys; 1952 1953 /* SCTP AUTH: 1954 * The current generated assocaition shared key (secret) 1955 */ 1956 struct sctp_auth_bytes *asoc_shared_key; 1957 1958 /* SCTP AUTH: hmac id of the first peer requested algorithm 1959 * that we support. 1960 */ 1961 __u16 default_hmac_id; 1962 1963 __u16 active_key_id; 1964 1965 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */ 1966 temp:1; /* Is it a temporary association? */ 1967 }; 1968 1969 1970 /* An eyecatcher for determining if we are really looking at an 1971 * association data structure. 1972 */ 1973 enum { 1974 SCTP_ASSOC_EYECATCHER = 0xa550c123, 1975 }; 1976 1977 /* Recover the outter association structure. */ 1978 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base) 1979 { 1980 struct sctp_association *asoc; 1981 1982 asoc = container_of(base, struct sctp_association, base); 1983 return asoc; 1984 } 1985 1986 /* These are function signatures for manipulating associations. */ 1987 1988 1989 struct sctp_association * 1990 sctp_association_new(const struct sctp_endpoint *, const struct sock *, 1991 sctp_scope_t scope, gfp_t gfp); 1992 void sctp_association_free(struct sctp_association *); 1993 void sctp_association_put(struct sctp_association *); 1994 void sctp_association_hold(struct sctp_association *); 1995 1996 struct sctp_transport *sctp_assoc_choose_alter_transport( 1997 struct sctp_association *, struct sctp_transport *); 1998 void sctp_assoc_update_retran_path(struct sctp_association *); 1999 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *, 2000 const union sctp_addr *); 2001 int sctp_assoc_lookup_laddr(struct sctp_association *asoc, 2002 const union sctp_addr *laddr); 2003 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *, 2004 const union sctp_addr *address, 2005 const gfp_t gfp, 2006 const int peer_state); 2007 void sctp_assoc_del_peer(struct sctp_association *asoc, 2008 const union sctp_addr *addr); 2009 void sctp_assoc_rm_peer(struct sctp_association *asoc, 2010 struct sctp_transport *peer); 2011 void sctp_assoc_control_transport(struct sctp_association *, 2012 struct sctp_transport *, 2013 sctp_transport_cmd_t, sctp_sn_error_t); 2014 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32); 2015 struct sctp_transport *sctp_assoc_is_match(struct sctp_association *, 2016 const union sctp_addr *, 2017 const union sctp_addr *); 2018 void sctp_assoc_migrate(struct sctp_association *, struct sock *); 2019 void sctp_assoc_update(struct sctp_association *old, 2020 struct sctp_association *new); 2021 2022 __u32 sctp_association_get_next_tsn(struct sctp_association *); 2023 2024 void sctp_assoc_sync_pmtu(struct sock *, struct sctp_association *); 2025 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int); 2026 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int); 2027 void sctp_assoc_set_primary(struct sctp_association *, 2028 struct sctp_transport *); 2029 void sctp_assoc_del_nonprimary_peers(struct sctp_association *, 2030 struct sctp_transport *); 2031 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *, 2032 sctp_scope_t, gfp_t); 2033 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *, 2034 struct sctp_cookie*, 2035 gfp_t gfp); 2036 int sctp_assoc_set_id(struct sctp_association *, gfp_t); 2037 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc); 2038 struct sctp_chunk *sctp_assoc_lookup_asconf_ack( 2039 const struct sctp_association *asoc, 2040 __be32 serial); 2041 void sctp_asconf_queue_teardown(struct sctp_association *asoc); 2042 2043 int sctp_cmp_addr_exact(const union sctp_addr *ss1, 2044 const union sctp_addr *ss2); 2045 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc); 2046 2047 /* A convenience structure to parse out SCTP specific CMSGs. */ 2048 typedef struct sctp_cmsgs { 2049 struct sctp_initmsg *init; 2050 struct sctp_sndrcvinfo *info; 2051 } sctp_cmsgs_t; 2052 2053 /* Structure for tracking memory objects */ 2054 typedef struct { 2055 char *label; 2056 atomic_t *counter; 2057 } sctp_dbg_objcnt_entry_t; 2058 2059 #endif /* __sctp_structs_h__ */ 2060