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