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, see 23 * <http://www.gnu.org/licenses/>. 24 * 25 * Please send any bug reports or fixes you make to the 26 * email addresses: 27 * lksctp developers <linux-sctp@vger.kernel.org> 28 * 29 * Written or modified by: 30 * Randall Stewart <randall@sctp.chicago.il.us> 31 * Ken Morneau <kmorneau@cisco.com> 32 * Qiaobing Xie <qxie1@email.mot.com> 33 * La Monte H.P. Yarroll <piggy@acm.org> 34 * Karl Knutson <karl@athena.chicago.il.us> 35 * Jon Grimm <jgrimm@us.ibm.com> 36 * Xingang Guo <xingang.guo@intel.com> 37 * Hui Huang <hui.huang@nokia.com> 38 * Sridhar Samudrala <sri@us.ibm.com> 39 * Daisy Chang <daisyc@us.ibm.com> 40 * Dajiang Zhang <dajiang.zhang@nokia.com> 41 * Ardelle Fan <ardelle.fan@intel.com> 42 * Ryan Layer <rmlayer@us.ibm.com> 43 * Anup Pemmaiah <pemmaiah@cc.usu.edu> 44 * Kevin Gao <kevin.gao@intel.com> 45 */ 46 47#ifndef __sctp_structs_h__ 48#define __sctp_structs_h__ 49 50#include <linux/ktime.h> 51#include <linux/rhashtable.h> 52#include <linux/socket.h> /* linux/in.h needs this!! */ 53#include <linux/in.h> /* We get struct sockaddr_in. */ 54#include <linux/in6.h> /* We get struct in6_addr */ 55#include <linux/ipv6.h> 56#include <asm/param.h> /* We get MAXHOSTNAMELEN. */ 57#include <linux/atomic.h> /* This gets us atomic counters. */ 58#include <linux/skbuff.h> /* We need sk_buff_head. */ 59#include <linux/workqueue.h> /* We need tq_struct. */ 60#include <linux/sctp.h> /* We need sctp* header structs. */ 61#include <net/sctp/auth.h> /* We need auth specific structs */ 62 63/* A convenience structure for handling sockaddr structures. 64 * We should wean ourselves off this. 65 */ 66union sctp_addr { 67 struct sockaddr_in v4; 68 struct sockaddr_in6 v6; 69 struct sockaddr sa; 70}; 71 72/* Forward declarations for data structures. */ 73struct sctp_globals; 74struct sctp_endpoint; 75struct sctp_association; 76struct sctp_transport; 77struct sctp_packet; 78struct sctp_chunk; 79struct sctp_inq; 80struct sctp_outq; 81struct sctp_bind_addr; 82struct sctp_ulpq; 83struct sctp_ep_common; 84struct sctp_ssnmap; 85struct crypto_shash; 86 87 88#include <net/sctp/tsnmap.h> 89#include <net/sctp/ulpevent.h> 90#include <net/sctp/ulpqueue.h> 91 92/* Structures useful for managing bind/connect. */ 93 94struct sctp_bind_bucket { 95 unsigned short port; 96 unsigned short fastreuse; 97 struct hlist_node node; 98 struct hlist_head owner; 99 struct net *net; 100}; 101 102struct sctp_bind_hashbucket { 103 spinlock_t lock; 104 struct hlist_head chain; 105}; 106 107/* Used for hashing all associations. */ 108struct sctp_hashbucket { 109 rwlock_t lock; 110 struct hlist_head chain; 111} __attribute__((__aligned__(8))); 112 113 114/* The SCTP globals structure. */ 115extern struct sctp_globals { 116 /* This is a list of groups of functions for each address 117 * family that we support. 118 */ 119 struct list_head address_families; 120 121 /* This is the hash of all endpoints. */ 122 struct sctp_hashbucket *ep_hashtable; 123 /* This is the sctp port control hash. */ 124 struct sctp_bind_hashbucket *port_hashtable; 125 /* This is the hash of all transports. */ 126 struct rhashtable transport_hashtable; 127 128 /* Sizes of above hashtables. */ 129 int ep_hashsize; 130 int port_hashsize; 131 132 /* Default initialization values to be applied to new associations. */ 133 __u16 max_instreams; 134 __u16 max_outstreams; 135 136 /* Flag to indicate whether computing and verifying checksum 137 * is disabled. */ 138 bool checksum_disable; 139} sctp_globals; 140 141#define sctp_max_instreams (sctp_globals.max_instreams) 142#define sctp_max_outstreams (sctp_globals.max_outstreams) 143#define sctp_address_families (sctp_globals.address_families) 144#define sctp_ep_hashsize (sctp_globals.ep_hashsize) 145#define sctp_ep_hashtable (sctp_globals.ep_hashtable) 146#define sctp_port_hashsize (sctp_globals.port_hashsize) 147#define sctp_port_hashtable (sctp_globals.port_hashtable) 148#define sctp_transport_hashtable (sctp_globals.transport_hashtable) 149#define sctp_checksum_disable (sctp_globals.checksum_disable) 150 151/* SCTP Socket type: UDP or TCP style. */ 152typedef enum { 153 SCTP_SOCKET_UDP = 0, 154 SCTP_SOCKET_UDP_HIGH_BANDWIDTH, 155 SCTP_SOCKET_TCP 156} sctp_socket_type_t; 157 158/* Per socket SCTP information. */ 159struct sctp_sock { 160 /* inet_sock has to be the first member of sctp_sock */ 161 struct inet_sock inet; 162 /* What kind of a socket is this? */ 163 sctp_socket_type_t type; 164 165 /* PF_ family specific functions. */ 166 struct sctp_pf *pf; 167 168 /* Access to HMAC transform. */ 169 struct crypto_shash *hmac; 170 char *sctp_hmac_alg; 171 172 /* What is our base endpointer? */ 173 struct sctp_endpoint *ep; 174 175 struct sctp_bind_bucket *bind_hash; 176 /* Various Socket Options. */ 177 __u16 default_stream; 178 __u32 default_ppid; 179 __u16 default_flags; 180 __u32 default_context; 181 __u32 default_timetolive; 182 __u32 default_rcv_context; 183 int max_burst; 184 185 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 186 * the destination address every heartbeat interval. This value 187 * will be inherited by all new associations. 188 */ 189 __u32 hbinterval; 190 191 /* This is the max_retrans value for new associations. */ 192 __u16 pathmaxrxt; 193 194 /* The initial Path MTU to use for new associations. */ 195 __u32 pathmtu; 196 197 /* The default SACK delay timeout for new associations. */ 198 __u32 sackdelay; 199 __u32 sackfreq; 200 201 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 202 __u32 param_flags; 203 204 struct sctp_initmsg initmsg; 205 struct sctp_rtoinfo rtoinfo; 206 struct sctp_paddrparams paddrparam; 207 struct sctp_event_subscribe subscribe; 208 struct sctp_assocparams assocparams; 209 210 int user_frag; 211 212 __u32 autoclose; 213 __u8 nodelay; 214 __u8 disable_fragments; 215 __u8 v4mapped; 216 __u8 frag_interleave; 217 __u32 adaptation_ind; 218 __u32 pd_point; 219 __u8 recvrcvinfo; 220 __u8 recvnxtinfo; 221 222 atomic_t pd_mode; 223 /* Receive to here while partial delivery is in effect. */ 224 struct sk_buff_head pd_lobby; 225 226 /* These must be the last fields, as they will skipped on copies, 227 * like on accept and peeloff operations 228 */ 229 struct list_head auto_asconf_list; 230 int do_auto_asconf; 231}; 232 233static inline struct sctp_sock *sctp_sk(const struct sock *sk) 234{ 235 return (struct sctp_sock *)sk; 236} 237 238static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp) 239{ 240 return (struct sock *)sp; 241} 242 243#if IS_ENABLED(CONFIG_IPV6) 244struct sctp6_sock { 245 struct sctp_sock sctp; 246 struct ipv6_pinfo inet6; 247}; 248#endif /* CONFIG_IPV6 */ 249 250 251/* This is our APPLICATION-SPECIFIC state cookie. 252 * THIS IS NOT DICTATED BY THE SPECIFICATION. 253 */ 254/* These are the parts of an association which we send in the cookie. 255 * Most of these are straight out of: 256 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB) 257 * 258 */ 259 260struct sctp_cookie { 261 262 /* My : Tag expected in every inbound packet and sent 263 * Verification: in the INIT or INIT ACK chunk. 264 * Tag : 265 */ 266 __u32 my_vtag; 267 268 /* Peer's : Tag expected in every outbound packet except 269 * Verification: in the INIT chunk. 270 * Tag : 271 */ 272 __u32 peer_vtag; 273 274 /* The rest of these are not from the spec, but really need to 275 * be in the cookie. 276 */ 277 278 /* My Tie Tag : Assist in discovering a restarting association. */ 279 __u32 my_ttag; 280 281 /* Peer's Tie Tag: Assist in discovering a restarting association. */ 282 __u32 peer_ttag; 283 284 /* When does this cookie expire? */ 285 ktime_t expiration; 286 287 /* Number of inbound/outbound streams which are set 288 * and negotiated during the INIT process. 289 */ 290 __u16 sinit_num_ostreams; 291 __u16 sinit_max_instreams; 292 293 /* This is the first sequence number I used. */ 294 __u32 initial_tsn; 295 296 /* This holds the originating address of the INIT packet. */ 297 union sctp_addr peer_addr; 298 299 /* IG Section 2.35.3 300 * Include the source port of the INIT-ACK 301 */ 302 __u16 my_port; 303 304 __u8 prsctp_capable; 305 306 /* Padding for future use */ 307 __u8 padding; 308 309 __u32 adaptation_ind; 310 311 __u8 auth_random[sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH]; 312 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2]; 313 __u8 auth_chunks[sizeof(sctp_paramhdr_t) + SCTP_AUTH_MAX_CHUNKS]; 314 315 /* This is a shim for my peer's INIT packet, followed by 316 * a copy of the raw address list of the association. 317 * The length of the raw address list is saved in the 318 * raw_addr_list_len field, which will be used at the time when 319 * the association TCB is re-constructed from the cookie. 320 */ 321 __u32 raw_addr_list_len; 322 struct sctp_init_chunk peer_init[0]; 323}; 324 325 326/* The format of our cookie that we send to our peer. */ 327struct sctp_signed_cookie { 328 __u8 signature[SCTP_SECRET_SIZE]; 329 __u32 __pad; /* force sctp_cookie alignment to 64 bits */ 330 struct sctp_cookie c; 331} __packed; 332 333/* This is another convenience type to allocate memory for address 334 * params for the maximum size and pass such structures around 335 * internally. 336 */ 337union sctp_addr_param { 338 struct sctp_paramhdr p; 339 struct sctp_ipv4addr_param v4; 340 struct sctp_ipv6addr_param v6; 341}; 342 343/* A convenience type to allow walking through the various 344 * parameters and avoid casting all over the place. 345 */ 346union sctp_params { 347 void *v; 348 struct sctp_paramhdr *p; 349 struct sctp_cookie_preserve_param *life; 350 struct sctp_hostname_param *dns; 351 struct sctp_cookie_param *cookie; 352 struct sctp_supported_addrs_param *sat; 353 struct sctp_ipv4addr_param *v4; 354 struct sctp_ipv6addr_param *v6; 355 union sctp_addr_param *addr; 356 struct sctp_adaptation_ind_param *aind; 357 struct sctp_supported_ext_param *ext; 358 struct sctp_random_param *random; 359 struct sctp_chunks_param *chunks; 360 struct sctp_hmac_algo_param *hmac_algo; 361 struct sctp_addip_param *addip; 362}; 363 364/* RFC 2960. Section 3.3.5 Heartbeat. 365 * Heartbeat Information: variable length 366 * The Sender-specific Heartbeat Info field should normally include 367 * information about the sender's current time when this HEARTBEAT 368 * chunk is sent and the destination transport address to which this 369 * HEARTBEAT is sent (see Section 8.3). 370 */ 371typedef struct sctp_sender_hb_info { 372 struct sctp_paramhdr param_hdr; 373 union sctp_addr daddr; 374 unsigned long sent_at; 375 __u64 hb_nonce; 376} __packed sctp_sender_hb_info_t; 377 378/* 379 * RFC 2960 1.3.2 Sequenced Delivery within Streams 380 * 381 * The term "stream" is used in SCTP to refer to a sequence of user 382 * messages that are to be delivered to the upper-layer protocol in 383 * order with respect to other messages within the same stream. This is 384 * in contrast to its usage in TCP, where it refers to a sequence of 385 * bytes (in this document a byte is assumed to be eight bits). 386 * ... 387 * 388 * This is the structure we use to track both our outbound and inbound 389 * SSN, or Stream Sequence Numbers. 390 */ 391 392struct sctp_stream { 393 __u16 *ssn; 394 unsigned int len; 395}; 396 397struct sctp_ssnmap { 398 struct sctp_stream in; 399 struct sctp_stream out; 400}; 401 402struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out, 403 gfp_t gfp); 404void sctp_ssnmap_free(struct sctp_ssnmap *map); 405void sctp_ssnmap_clear(struct sctp_ssnmap *map); 406 407/* What is the current SSN number for this stream? */ 408static inline __u16 sctp_ssn_peek(struct sctp_stream *stream, __u16 id) 409{ 410 return stream->ssn[id]; 411} 412 413/* Return the next SSN number for this stream. */ 414static inline __u16 sctp_ssn_next(struct sctp_stream *stream, __u16 id) 415{ 416 return stream->ssn[id]++; 417} 418 419/* Skip over this ssn and all below. */ 420static inline void sctp_ssn_skip(struct sctp_stream *stream, __u16 id, 421 __u16 ssn) 422{ 423 stream->ssn[id] = ssn+1; 424} 425 426/* 427 * Pointers to address related SCTP functions. 428 * (i.e. things that depend on the address family.) 429 */ 430struct sctp_af { 431 int (*sctp_xmit) (struct sk_buff *skb, 432 struct sctp_transport *); 433 int (*setsockopt) (struct sock *sk, 434 int level, 435 int optname, 436 char __user *optval, 437 unsigned int optlen); 438 int (*getsockopt) (struct sock *sk, 439 int level, 440 int optname, 441 char __user *optval, 442 int __user *optlen); 443 int (*compat_setsockopt) (struct sock *sk, 444 int level, 445 int optname, 446 char __user *optval, 447 unsigned int optlen); 448 int (*compat_getsockopt) (struct sock *sk, 449 int level, 450 int optname, 451 char __user *optval, 452 int __user *optlen); 453 void (*get_dst) (struct sctp_transport *t, 454 union sctp_addr *saddr, 455 struct flowi *fl, 456 struct sock *sk); 457 void (*get_saddr) (struct sctp_sock *sk, 458 struct sctp_transport *t, 459 struct flowi *fl); 460 void (*copy_addrlist) (struct list_head *, 461 struct net_device *); 462 int (*cmp_addr) (const union sctp_addr *addr1, 463 const union sctp_addr *addr2); 464 void (*addr_copy) (union sctp_addr *dst, 465 union sctp_addr *src); 466 void (*from_skb) (union sctp_addr *, 467 struct sk_buff *skb, 468 int saddr); 469 void (*from_sk) (union sctp_addr *, 470 struct sock *sk); 471 void (*from_addr_param) (union sctp_addr *, 472 union sctp_addr_param *, 473 __be16 port, int iif); 474 int (*to_addr_param) (const union sctp_addr *, 475 union sctp_addr_param *); 476 int (*addr_valid) (union sctp_addr *, 477 struct sctp_sock *, 478 const struct sk_buff *); 479 sctp_scope_t (*scope) (union sctp_addr *); 480 void (*inaddr_any) (union sctp_addr *, __be16); 481 int (*is_any) (const union sctp_addr *); 482 int (*available) (union sctp_addr *, 483 struct sctp_sock *); 484 int (*skb_iif) (const struct sk_buff *sk); 485 int (*is_ce) (const struct sk_buff *sk); 486 void (*seq_dump_addr)(struct seq_file *seq, 487 union sctp_addr *addr); 488 void (*ecn_capable)(struct sock *sk); 489 __u16 net_header_len; 490 int sockaddr_len; 491 sa_family_t sa_family; 492 struct list_head list; 493}; 494 495struct sctp_af *sctp_get_af_specific(sa_family_t); 496int sctp_register_af(struct sctp_af *); 497 498/* Protocol family functions. */ 499struct sctp_pf { 500 void (*event_msgname)(struct sctp_ulpevent *, char *, int *); 501 void (*skb_msgname) (struct sk_buff *, char *, int *); 502 int (*af_supported) (sa_family_t, struct sctp_sock *); 503 int (*cmp_addr) (const union sctp_addr *, 504 const union sctp_addr *, 505 struct sctp_sock *); 506 int (*bind_verify) (struct sctp_sock *, union sctp_addr *); 507 int (*send_verify) (struct sctp_sock *, union sctp_addr *); 508 int (*supported_addrs)(const struct sctp_sock *, __be16 *); 509 struct sock *(*create_accept_sk) (struct sock *sk, 510 struct sctp_association *asoc); 511 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr); 512 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk); 513 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk); 514 struct sctp_af *af; 515}; 516 517 518/* Structure to track chunk fragments that have been acked, but peer 519 * fragments of the same message have not. 520 */ 521struct sctp_datamsg { 522 /* Chunks waiting to be submitted to lower layer. */ 523 struct list_head chunks; 524 /* Reference counting. */ 525 atomic_t refcnt; 526 /* When is this message no longer interesting to the peer? */ 527 unsigned long expires_at; 528 /* Did the messenge fail to send? */ 529 int send_error; 530 u8 send_failed:1, 531 can_abandon:1, /* can chunks from this message can be abandoned. */ 532 can_delay; /* should this message be Nagle delayed */ 533}; 534 535struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *, 536 struct sctp_sndrcvinfo *, 537 struct iov_iter *); 538void sctp_datamsg_put(struct sctp_datamsg *); 539void sctp_chunk_fail(struct sctp_chunk *, int error); 540int sctp_chunk_abandoned(struct sctp_chunk *); 541 542/* RFC2960 1.4 Key Terms 543 * 544 * o Chunk: A unit of information within an SCTP packet, consisting of 545 * a chunk header and chunk-specific content. 546 * 547 * As a matter of convenience, we remember the SCTP common header for 548 * each chunk as well as a few other header pointers... 549 */ 550struct sctp_chunk { 551 struct list_head list; 552 553 atomic_t refcnt; 554 555 /* This is our link to the per-transport transmitted list. */ 556 struct list_head transmitted_list; 557 558 /* This field is used by chunks that hold fragmented data. 559 * For the first fragment this is the list that holds the rest of 560 * fragments. For the remaining fragments, this is the link to the 561 * frag_list maintained in the first fragment. 562 */ 563 struct list_head frag_list; 564 565 /* This points to the sk_buff containing the actual data. */ 566 struct sk_buff *skb; 567 568 /* These are the SCTP headers by reverse order in a packet. 569 * Note that some of these may happen more than once. In that 570 * case, we point at the "current" one, whatever that means 571 * for that level of header. 572 */ 573 574 /* We point this at the FIRST TLV parameter to chunk_hdr. */ 575 union sctp_params param_hdr; 576 union { 577 __u8 *v; 578 struct sctp_datahdr *data_hdr; 579 struct sctp_inithdr *init_hdr; 580 struct sctp_sackhdr *sack_hdr; 581 struct sctp_heartbeathdr *hb_hdr; 582 struct sctp_sender_hb_info *hbs_hdr; 583 struct sctp_shutdownhdr *shutdown_hdr; 584 struct sctp_signed_cookie *cookie_hdr; 585 struct sctp_ecnehdr *ecne_hdr; 586 struct sctp_cwrhdr *ecn_cwr_hdr; 587 struct sctp_errhdr *err_hdr; 588 struct sctp_addiphdr *addip_hdr; 589 struct sctp_fwdtsn_hdr *fwdtsn_hdr; 590 struct sctp_authhdr *auth_hdr; 591 } subh; 592 593 __u8 *chunk_end; 594 595 struct sctp_chunkhdr *chunk_hdr; 596 struct sctphdr *sctp_hdr; 597 598 /* This needs to be recoverable for SCTP_SEND_FAILED events. */ 599 struct sctp_sndrcvinfo sinfo; 600 601 /* Which association does this belong to? */ 602 struct sctp_association *asoc; 603 604 /* What endpoint received this chunk? */ 605 struct sctp_ep_common *rcvr; 606 607 /* We fill this in if we are calculating RTT. */ 608 unsigned long sent_at; 609 610 /* What is the origin IP address for this chunk? */ 611 union sctp_addr source; 612 /* Destination address for this chunk. */ 613 union sctp_addr dest; 614 615 /* For outbound message, track all fragments for SEND_FAILED. */ 616 struct sctp_datamsg *msg; 617 618 /* For an inbound chunk, this tells us where it came from. 619 * For an outbound chunk, it tells us where we'd like it to 620 * go. It is NULL if we have no preference. 621 */ 622 struct sctp_transport *transport; 623 624 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO 625 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH 626 * spec violates the principle premis that all chunks are processed 627 * in order. 628 */ 629 struct sk_buff *auth_chunk; 630 631#define SCTP_CAN_FRTX 0x0 632#define SCTP_NEED_FRTX 0x1 633#define SCTP_DONT_FRTX 0x2 634 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */ 635 resent:1, /* Has this chunk ever been resent. */ 636 has_tsn:1, /* Does this chunk have a TSN yet? */ 637 has_ssn:1, /* Does this chunk have a SSN yet? */ 638 singleton:1, /* Only chunk in the packet? */ 639 end_of_packet:1, /* Last chunk in the packet? */ 640 ecn_ce_done:1, /* Have we processed the ECN CE bit? */ 641 pdiscard:1, /* Discard the whole packet now? */ 642 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */ 643 data_accepted:1, /* At least 1 chunk accepted */ 644 auth:1, /* IN: was auth'ed | OUT: needs auth */ 645 has_asconf:1, /* IN: have seen an asconf before */ 646 tsn_missing_report:2, /* Data chunk missing counter. */ 647 fast_retransmit:2; /* Is this chunk fast retransmitted? */ 648}; 649 650void sctp_chunk_hold(struct sctp_chunk *); 651void sctp_chunk_put(struct sctp_chunk *); 652int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len, 653 struct iov_iter *from); 654void sctp_chunk_free(struct sctp_chunk *); 655void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data); 656struct sctp_chunk *sctp_chunkify(struct sk_buff *, 657 const struct sctp_association *, 658 struct sock *, gfp_t gfp); 659void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *, 660 union sctp_addr *); 661const union sctp_addr *sctp_source(const struct sctp_chunk *chunk); 662 663enum { 664 SCTP_ADDR_NEW, /* new address added to assoc/ep */ 665 SCTP_ADDR_SRC, /* address can be used as source */ 666 SCTP_ADDR_DEL, /* address about to be deleted */ 667}; 668 669/* This is a structure for holding either an IPv6 or an IPv4 address. */ 670struct sctp_sockaddr_entry { 671 struct list_head list; 672 struct rcu_head rcu; 673 union sctp_addr a; 674 __u8 state; 675 __u8 valid; 676}; 677 678#define SCTP_ADDRESS_TICK_DELAY 500 679 680typedef struct sctp_chunk *(sctp_packet_phandler_t)(struct sctp_association *); 681 682/* This structure holds lists of chunks as we are assembling for 683 * transmission. 684 */ 685struct sctp_packet { 686 /* These are the SCTP header values (host order) for the packet. */ 687 __u16 source_port; 688 __u16 destination_port; 689 __u32 vtag; 690 691 /* This contains the payload chunks. */ 692 struct list_head chunk_list; 693 694 /* This is the overhead of the sctp and ip headers. */ 695 size_t overhead; 696 /* This is the total size of all chunks INCLUDING padding. */ 697 size_t size; 698 699 /* The packet is destined for this transport address. 700 * The function we finally use to pass down to the next lower 701 * layer lives in the transport structure. 702 */ 703 struct sctp_transport *transport; 704 705 /* pointer to the auth chunk for this packet */ 706 struct sctp_chunk *auth; 707 708 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */ 709 has_sack:1, /* This packet contains a SACK chunk. */ 710 has_auth:1, /* This packet contains an AUTH chunk */ 711 has_data:1, /* This packet contains at least 1 DATA chunk */ 712 ipfragok:1; /* So let ip fragment this packet */ 713}; 714 715struct sctp_packet *sctp_packet_init(struct sctp_packet *, 716 struct sctp_transport *, 717 __u16 sport, __u16 dport); 718struct sctp_packet *sctp_packet_config(struct sctp_packet *, __u32 vtag, int); 719sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *, 720 struct sctp_chunk *, int, gfp_t); 721sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *, 722 struct sctp_chunk *); 723int sctp_packet_transmit(struct sctp_packet *, gfp_t); 724void sctp_packet_free(struct sctp_packet *); 725 726static inline int sctp_packet_empty(struct sctp_packet *packet) 727{ 728 return packet->size == packet->overhead; 729} 730 731/* This represents a remote transport address. 732 * For local transport addresses, we just use union sctp_addr. 733 * 734 * RFC2960 Section 1.4 Key Terms 735 * 736 * o Transport address: A Transport Address is traditionally defined 737 * by Network Layer address, Transport Layer protocol and Transport 738 * Layer port number. In the case of SCTP running over IP, a 739 * transport address is defined by the combination of an IP address 740 * and an SCTP port number (where SCTP is the Transport protocol). 741 * 742 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control 743 * 744 * o The sender keeps a separate congestion control parameter set for 745 * each of the destination addresses it can send to (not each 746 * source-destination pair but for each destination). The parameters 747 * should decay if the address is not used for a long enough time 748 * period. 749 * 750 */ 751struct sctp_transport { 752 /* A list of transports. */ 753 struct list_head transports; 754 struct rhash_head node; 755 756 /* Reference counting. */ 757 atomic_t refcnt; 758 /* RTO-Pending : A flag used to track if one of the DATA 759 * chunks sent to this address is currently being 760 * used to compute a RTT. If this flag is 0, 761 * the next DATA chunk sent to this destination 762 * should be used to compute a RTT and this flag 763 * should be set. Every time the RTT 764 * calculation completes (i.e. the DATA chunk 765 * is SACK'd) clear this flag. 766 */ 767 __u32 rto_pending:1, 768 769 /* 770 * hb_sent : a flag that signals that we have a pending 771 * heartbeat. 772 */ 773 hb_sent:1, 774 775 /* Is the Path MTU update pending on this tranport */ 776 pmtu_pending:1, 777 778 /* Has this transport moved the ctsn since we last sacked */ 779 sack_generation:1; 780 u32 dst_cookie; 781 782 struct flowi fl; 783 784 /* This is the peer's IP address and port. */ 785 union sctp_addr ipaddr; 786 787 /* These are the functions we call to handle LLP stuff. */ 788 struct sctp_af *af_specific; 789 790 /* Which association do we belong to? */ 791 struct sctp_association *asoc; 792 793 /* RFC2960 794 * 795 * 12.3 Per Transport Address Data 796 * 797 * For each destination transport address in the peer's 798 * address list derived from the INIT or INIT ACK chunk, a 799 * number of data elements needs to be maintained including: 800 */ 801 /* RTO : The current retransmission timeout value. */ 802 unsigned long rto; 803 804 __u32 rtt; /* This is the most recent RTT. */ 805 806 /* RTTVAR : The current RTT variation. */ 807 __u32 rttvar; 808 809 /* SRTT : The current smoothed round trip time. */ 810 __u32 srtt; 811 812 /* 813 * These are the congestion stats. 814 */ 815 /* cwnd : The current congestion window. */ 816 __u32 cwnd; /* This is the actual cwnd. */ 817 818 /* ssthresh : The current slow start threshold value. */ 819 __u32 ssthresh; 820 821 /* partial : The tracking method for increase of cwnd when in 822 * bytes acked : congestion avoidance mode (see Section 6.2.2) 823 */ 824 __u32 partial_bytes_acked; 825 826 /* Data that has been sent, but not acknowledged. */ 827 __u32 flight_size; 828 829 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */ 830 831 /* Destination */ 832 struct dst_entry *dst; 833 /* Source address. */ 834 union sctp_addr saddr; 835 836 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 837 * the destination address every heartbeat interval. 838 */ 839 unsigned long hbinterval; 840 841 /* SACK delay timeout */ 842 unsigned long sackdelay; 843 __u32 sackfreq; 844 845 /* When was the last time that we heard from this transport? We use 846 * this to pick new active and retran paths. 847 */ 848 ktime_t last_time_heard; 849 850 /* When was the last time that we sent a chunk using this 851 * transport? We use this to check for idle transports 852 */ 853 unsigned long last_time_sent; 854 855 /* Last time(in jiffies) when cwnd is reduced due to the congestion 856 * indication based on ECNE chunk. 857 */ 858 unsigned long last_time_ecne_reduced; 859 860 /* This is the max_retrans value for the transport and will 861 * be initialized from the assocs value. This can be changed 862 * using the SCTP_SET_PEER_ADDR_PARAMS socket option. 863 */ 864 __u16 pathmaxrxt; 865 866 /* This is the partially failed retrans value for the transport 867 * and will be initialized from the assocs value. This can be changed 868 * using the SCTP_PEER_ADDR_THLDS socket option 869 */ 870 int pf_retrans; 871 /* PMTU : The current known path MTU. */ 872 __u32 pathmtu; 873 874 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 875 __u32 param_flags; 876 877 /* The number of times INIT has been sent on this transport. */ 878 int init_sent_count; 879 880 /* state : The current state of this destination, 881 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN. 882 */ 883 int state; 884 885 /* These are the error stats for this destination. */ 886 887 /* Error count : The current error count for this destination. */ 888 unsigned short error_count; 889 890 /* Per : A timer used by each destination. 891 * Destination : 892 * Timer : 893 * 894 * [Everywhere else in the text this is called T3-rtx. -ed] 895 */ 896 struct timer_list T3_rtx_timer; 897 898 /* Heartbeat timer is per destination. */ 899 struct timer_list hb_timer; 900 901 /* Timer to handle ICMP proto unreachable envets */ 902 struct timer_list proto_unreach_timer; 903 904 /* Since we're using per-destination retransmission timers 905 * (see above), we're also using per-destination "transmitted" 906 * queues. This probably ought to be a private struct 907 * accessible only within the outqueue, but it's not, yet. 908 */ 909 struct list_head transmitted; 910 911 /* We build bundle-able packets for this transport here. */ 912 struct sctp_packet packet; 913 914 /* This is the list of transports that have chunks to send. */ 915 struct list_head send_ready; 916 917 /* State information saved for SFR_CACC algorithm. The key 918 * idea in SFR_CACC is to maintain state at the sender on a 919 * per-destination basis when a changeover happens. 920 * char changeover_active; 921 * char cycling_changeover; 922 * __u32 next_tsn_at_change; 923 * char cacc_saw_newack; 924 */ 925 struct { 926 /* An unsigned integer, which stores the next TSN to be 927 * used by the sender, at the moment of changeover. 928 */ 929 __u32 next_tsn_at_change; 930 931 /* A flag which indicates the occurrence of a changeover */ 932 char changeover_active; 933 934 /* A flag which indicates whether the change of primary is 935 * the first switch to this destination address during an 936 * active switch. 937 */ 938 char cycling_changeover; 939 940 /* A temporary flag, which is used during the processing of 941 * a SACK to estimate the causative TSN(s)'s group. 942 */ 943 char cacc_saw_newack; 944 } cacc; 945 946 /* 64-bit random number sent with heartbeat. */ 947 __u64 hb_nonce; 948 949 struct rcu_head rcu; 950}; 951 952struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *, 953 gfp_t); 954void sctp_transport_set_owner(struct sctp_transport *, 955 struct sctp_association *); 956void sctp_transport_route(struct sctp_transport *, union sctp_addr *, 957 struct sctp_sock *); 958void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk); 959void sctp_transport_free(struct sctp_transport *); 960void sctp_transport_reset_t3_rtx(struct sctp_transport *); 961void sctp_transport_reset_hb_timer(struct sctp_transport *); 962int sctp_transport_hold(struct sctp_transport *); 963void sctp_transport_put(struct sctp_transport *); 964void sctp_transport_update_rto(struct sctp_transport *, __u32); 965void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32); 966void sctp_transport_lower_cwnd(struct sctp_transport *, sctp_lower_cwnd_t); 967void sctp_transport_burst_limited(struct sctp_transport *); 968void sctp_transport_burst_reset(struct sctp_transport *); 969unsigned long sctp_transport_timeout(struct sctp_transport *); 970void sctp_transport_reset(struct sctp_transport *); 971void sctp_transport_update_pmtu(struct sock *, struct sctp_transport *, u32); 972void sctp_transport_immediate_rtx(struct sctp_transport *); 973 974 975/* This is the structure we use to queue packets as they come into 976 * SCTP. We write packets to it and read chunks from it. 977 */ 978struct sctp_inq { 979 /* This is actually a queue of sctp_chunk each 980 * containing a partially decoded packet. 981 */ 982 struct list_head in_chunk_list; 983 /* This is the packet which is currently off the in queue and is 984 * being worked on through the inbound chunk processing. 985 */ 986 struct sctp_chunk *in_progress; 987 988 /* This is the delayed task to finish delivering inbound 989 * messages. 990 */ 991 struct work_struct immediate; 992}; 993 994void sctp_inq_init(struct sctp_inq *); 995void sctp_inq_free(struct sctp_inq *); 996void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet); 997struct sctp_chunk *sctp_inq_pop(struct sctp_inq *); 998struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *); 999void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t); 1000
1001/* This is the structure we use to hold outbound chunks. You push 1002 * chunks in and they automatically pop out the other end as bundled 1003 * packets (it calls (*output_handler)()). 1004 * 1005 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1, 1006 * and 8.2 of the v13 draft. 1007 * 1008 * It handles retransmissions. The connection to the timeout portion 1009 * of the state machine is through sctp_..._timeout() and timeout_handler. 1010 * 1011 * If you feed it SACKs, it will eat them. 1012 * 1013 * If you give it big chunks, it will fragment them. 1014 * 1015 * It assigns TSN's to data chunks. This happens at the last possible 1016 * instant before transmission. 1017 * 1018 * When free()'d, it empties itself out via output_handler(). 1019 */ 1020struct sctp_outq { 1021 struct sctp_association *asoc; 1022 1023 /* Data pending that has never been transmitted. */ 1024 struct list_head out_chunk_list; 1025 1026 unsigned int out_qlen; /* Total length of queued data chunks. */ 1027 1028 /* Error of send failed, may used in SCTP_SEND_FAILED event. */ 1029 unsigned int error; 1030 1031 /* These are control chunks we want to send. */ 1032 struct list_head control_chunk_list; 1033 1034 /* These are chunks that have been sacked but are above the 1035 * CTSN, or cumulative tsn ack point. 1036 */ 1037 struct list_head sacked; 1038 1039 /* Put chunks on this list to schedule them for 1040 * retransmission. 1041 */ 1042 struct list_head retransmit; 1043 1044 /* Put chunks on this list to save them for FWD TSN processing as 1045 * they were abandoned. 1046 */ 1047 struct list_head abandoned; 1048 1049 /* How many unackd bytes do we have in-flight? */ 1050 __u32 outstanding_bytes; 1051 1052 /* Are we doing fast-rtx on this queue */ 1053 char fast_rtx; 1054 1055 /* Corked? */ 1056 char cork; 1057}; 1058 1059void sctp_outq_init(struct sctp_association *, struct sctp_outq *); 1060void sctp_outq_teardown(struct sctp_outq *); 1061void sctp_outq_free(struct sctp_outq*); 1062int sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t); 1063int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *); 1064int sctp_outq_is_empty(const struct sctp_outq *); 1065void sctp_outq_restart(struct sctp_outq *); 1066 1067void sctp_retransmit(struct sctp_outq *, struct sctp_transport *, 1068 sctp_retransmit_reason_t); 1069void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8); 1070int sctp_outq_uncork(struct sctp_outq *, gfp_t gfp); 1071/* Uncork and flush an outqueue. */ 1072static inline void sctp_outq_cork(struct sctp_outq *q) 1073{ 1074 q->cork = 1; 1075} 1076 1077/* These bind address data fields common between endpoints and associations */ 1078struct sctp_bind_addr { 1079 1080 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1081 * 1082 * SCTP Port: The local SCTP port number the endpoint is 1083 * bound to. 1084 */ 1085 __u16 port; 1086 1087 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1088 * 1089 * Address List: The list of IP addresses that this instance 1090 * has bound. This information is passed to one's 1091 * peer(s) in INIT and INIT ACK chunks. 1092 */ 1093 struct list_head address_list; 1094}; 1095 1096void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port); 1097void sctp_bind_addr_free(struct sctp_bind_addr *); 1098int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest, 1099 const struct sctp_bind_addr *src, 1100 sctp_scope_t scope, gfp_t gfp, 1101 int flags); 1102int sctp_bind_addr_dup(struct sctp_bind_addr *dest, 1103 const struct sctp_bind_addr *src, 1104 gfp_t gfp); 1105int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *, 1106 int new_size, __u8 addr_state, gfp_t gfp); 1107int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *); 1108int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *, 1109 struct sctp_sock *); 1110int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *, 1111 struct sctp_sock *, struct sctp_sock *); 1112int sctp_bind_addr_state(const struct sctp_bind_addr *bp, 1113 const union sctp_addr *addr); 1114union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp, 1115 const union sctp_addr *addrs, 1116 int addrcnt, 1117 struct sctp_sock *opt); 1118union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp, 1119 int *addrs_len, 1120 gfp_t gfp); 1121int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len, 1122 __u16 port, gfp_t gfp); 1123 1124sctp_scope_t sctp_scope(const union sctp_addr *); 1125int sctp_in_scope(struct net *net, const union sctp_addr *addr, const sctp_scope_t scope); 1126int sctp_is_any(struct sock *sk, const union sctp_addr *addr); 1127int sctp_is_ep_boundall(struct sock *sk); 1128 1129 1130/* What type of endpoint? */ 1131typedef enum { 1132 SCTP_EP_TYPE_SOCKET, 1133 SCTP_EP_TYPE_ASSOCIATION, 1134} sctp_endpoint_type_t; 1135 1136/* 1137 * A common base class to bridge the implmentation view of a 1138 * socket (usually listening) endpoint versus an association's 1139 * local endpoint. 1140 * This common structure is useful for several purposes: 1141 * 1) Common interface for lookup routines. 1142 * a) Subfunctions work for either endpoint or association 1143 * b) Single interface to lookup allows hiding the lookup lock rather 1144 * than acquiring it externally. 1145 * 2) Common interface for the inbound chunk handling/state machine. 1146 * 3) Common object handling routines for reference counting, etc. 1147 * 4) Disentangle association lookup from endpoint lookup, where we 1148 * do not have to find our endpoint to find our association. 1149 * 1150 */ 1151 1152struct sctp_ep_common { 1153 /* Fields to help us manage our entries in the hash tables. */ 1154 struct hlist_node node; 1155 int hashent; 1156 1157 /* Runtime type information. What kind of endpoint is this? */ 1158 sctp_endpoint_type_t type; 1159 1160 /* Some fields to help us manage this object. 1161 * refcnt - Reference count access to this object. 1162 * dead - Do not attempt to use this object. 1163 */ 1164 atomic_t refcnt; 1165 bool dead; 1166 1167 /* What socket does this endpoint belong to? */ 1168 struct sock *sk; 1169 1170 /* This is where we receive inbound chunks. */ 1171 struct sctp_inq inqueue; 1172 1173 /* This substructure includes the defining parameters of the 1174 * endpoint: 1175 * bind_addr.port is our shared port number. 1176 * bind_addr.address_list is our set of local IP addresses. 1177 */ 1178 struct sctp_bind_addr bind_addr; 1179}; 1180 1181 1182/* RFC Section 1.4 Key Terms 1183 * 1184 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a 1185 * multi-homed host, an SCTP endpoint is represented to its peers as a 1186 * combination of a set of eligible destination transport addresses to 1187 * which SCTP packets can be sent and a set of eligible source 1188 * transport addresses from which SCTP packets can be received. 1189 * All transport addresses used by an SCTP endpoint must use the 1190 * same port number, but can use multiple IP addresses. A transport 1191 * address used by an SCTP endpoint must not be used by another 1192 * SCTP endpoint. In other words, a transport address is unique 1193 * to an SCTP endpoint. 1194 * 1195 * From an implementation perspective, each socket has one of these. 1196 * A TCP-style socket will have exactly one association on one of 1197 * these. An UDP-style socket will have multiple associations hanging 1198 * off one of these. 1199 */ 1200 1201struct sctp_endpoint { 1202 /* Common substructure for endpoint and association. */ 1203 struct sctp_ep_common base; 1204 1205 /* Associations: A list of current associations and mappings 1206 * to the data consumers for each association. This 1207 * may be in the form of a hash table or other 1208 * implementation dependent structure. The data 1209 * consumers may be process identification 1210 * information such as file descriptors, named pipe 1211 * pointer, or table pointers dependent on how SCTP 1212 * is implemented. 1213 */ 1214 /* This is really a list of struct sctp_association entries. */ 1215 struct list_head asocs; 1216 1217 /* Secret Key: A secret key used by this endpoint to compute 1218 * the MAC. This SHOULD be a cryptographic quality 1219 * random number with a sufficient length. 1220 * Discussion in [RFC1750] can be helpful in 1221 * selection of the key. 1222 */ 1223 __u8 secret_key[SCTP_SECRET_SIZE]; 1224 1225 /* digest: This is a digest of the sctp cookie. This field is 1226 * only used on the receive path when we try to validate 1227 * that the cookie has not been tampered with. We put 1228 * this here so we pre-allocate this once and can re-use 1229 * on every receive. 1230 */ 1231 __u8 *digest; 1232 1233 /* sendbuf acct. policy. */ 1234 __u32 sndbuf_policy; 1235 1236 /* rcvbuf acct. policy. */ 1237 __u32 rcvbuf_policy; 1238 1239 /* SCTP AUTH: array of the HMACs that will be allocated 1240 * we need this per association so that we don't serialize 1241 */ 1242 struct crypto_shash **auth_hmacs; 1243 1244 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */ 1245 struct sctp_hmac_algo_param *auth_hmacs_list; 1246 1247 /* SCTP-AUTH: chunks to authenticate encoded into parameter */ 1248 struct sctp_chunks_param *auth_chunk_list; 1249 1250 /* SCTP-AUTH: endpoint shared keys */ 1251 struct list_head endpoint_shared_keys; 1252 __u16 active_key_id; 1253 __u8 auth_enable; 1254}; 1255 1256/* Recover the outter endpoint structure. */ 1257static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base) 1258{ 1259 struct sctp_endpoint *ep; 1260 1261 ep = container_of(base, struct sctp_endpoint, base); 1262 return ep; 1263} 1264 1265/* These are function signatures for manipulating endpoints. */ 1266struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t); 1267void sctp_endpoint_free(struct sctp_endpoint *); 1268void sctp_endpoint_put(struct sctp_endpoint *); 1269void sctp_endpoint_hold(struct sctp_endpoint *); 1270void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *); 1271struct sctp_association *sctp_endpoint_lookup_assoc( 1272 const struct sctp_endpoint *ep, 1273 const union sctp_addr *paddr, 1274 struct sctp_transport **); 1275int sctp_endpoint_is_peeled_off(struct sctp_endpoint *, 1276 const union sctp_addr *); 1277struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *, 1278 struct net *, const union sctp_addr *); 1279int sctp_has_association(struct net *net, const union sctp_addr *laddr, 1280 const union sctp_addr *paddr); 1281 1282int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep, 1283 const struct sctp_association *asoc, 1284 sctp_cid_t, sctp_init_chunk_t *peer_init, 1285 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk); 1286int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk, 1287 const union sctp_addr *peer, 1288 sctp_init_chunk_t *init, gfp_t gfp); 1289__u32 sctp_generate_tag(const struct sctp_endpoint *); 1290__u32 sctp_generate_tsn(const struct sctp_endpoint *); 1291 1292struct sctp_inithdr_host { 1293 __u32 init_tag; 1294 __u32 a_rwnd; 1295 __u16 num_outbound_streams; 1296 __u16 num_inbound_streams; 1297 __u32 initial_tsn; 1298}; 1299 1300/* SCTP_GET_ASSOC_STATS counters */ 1301struct sctp_priv_assoc_stats { 1302 /* Maximum observed rto in the association during subsequent 1303 * observations. Value is set to 0 if no RTO measurement took place 1304 * The transport where the max_rto was observed is returned in 1305 * obs_rto_ipaddr 1306 */ 1307 struct sockaddr_storage obs_rto_ipaddr; 1308 __u64 max_obs_rto; 1309 /* Total In and Out SACKs received and sent */ 1310 __u64 isacks; 1311 __u64 osacks; 1312 /* Total In and Out packets received and sent */ 1313 __u64 opackets; 1314 __u64 ipackets; 1315 /* Total retransmitted chunks */ 1316 __u64 rtxchunks; 1317 /* TSN received > next expected */ 1318 __u64 outofseqtsns; 1319 /* Duplicate Chunks received */ 1320 __u64 idupchunks; 1321 /* Gap Ack Blocks received */ 1322 __u64 gapcnt; 1323 /* Unordered data chunks sent and received */ 1324 __u64 ouodchunks; 1325 __u64 iuodchunks; 1326 /* Ordered data chunks sent and received */ 1327 __u64 oodchunks; 1328 __u64 iodchunks; 1329 /* Control chunks sent and received */ 1330 __u64 octrlchunks; 1331 __u64 ictrlchunks; 1332}; 1333 1334/* RFC2960 1335 * 1336 * 12. Recommended Transmission Control Block (TCB) Parameters 1337 * 1338 * This section details a recommended set of parameters that should 1339 * be contained within the TCB for an implementation. This section is 1340 * for illustrative purposes and should not be deemed as requirements 1341 * on an implementation or as an exhaustive list of all parameters 1342 * inside an SCTP TCB. Each implementation may need its own additional 1343 * parameters for optimization. 1344 */ 1345 1346 1347/* Here we have information about each individual association. */ 1348struct sctp_association { 1349 1350 /* A base structure common to endpoint and association. 1351 * In this context, it represents the associations's view 1352 * of the local endpoint of the association. 1353 */ 1354 struct sctp_ep_common base; 1355 1356 /* Associations on the same socket. */ 1357 struct list_head asocs; 1358 1359 /* association id. */ 1360 sctp_assoc_t assoc_id; 1361 1362 /* This is our parent endpoint. */ 1363 struct sctp_endpoint *ep; 1364 1365 /* These are those association elements needed in the cookie. */ 1366 struct sctp_cookie c; 1367 1368 /* This is all information about our peer. */ 1369 struct { 1370 /* transport_addr_list 1371 * 1372 * Peer : A list of SCTP transport addresses that the 1373 * Transport : peer is bound to. This information is derived 1374 * Address : from the INIT or INIT ACK and is used to 1375 * List : associate an inbound packet with a given 1376 * : association. Normally this information is 1377 * : hashed or keyed for quick lookup and access 1378 * : of the TCB. 1379 * : The list is also initialized with the list 1380 * : of addresses passed with the sctp_connectx() 1381 * : call. 1382 * 1383 * It is a list of SCTP_transport's. 1384 */ 1385 struct list_head transport_addr_list; 1386 1387 /* rwnd 1388 * 1389 * Peer Rwnd : Current calculated value of the peer's rwnd. 1390 */ 1391 __u32 rwnd; 1392 1393 /* transport_count 1394 * 1395 * Peer : A count of the number of peer addresses 1396 * Transport : in the Peer Transport Address List. 1397 * Address : 1398 * Count : 1399 */ 1400 __u16 transport_count; 1401 1402 /* port 1403 * The transport layer port number. 1404 */ 1405 __u16 port; 1406 1407 /* primary_path 1408 * 1409 * Primary : This is the current primary destination 1410 * Path : transport address of the peer endpoint. It 1411 * : may also specify a source transport address 1412 * : on this endpoint. 1413 * 1414 * All of these paths live on transport_addr_list. 1415 * 1416 * At the bakeoffs, we discovered that the intent of 1417 * primaryPath is that it only changes when the ULP 1418 * asks to have it changed. We add the activePath to 1419 * designate the connection we are currently using to 1420 * transmit new data and most control chunks. 1421 */ 1422 struct sctp_transport *primary_path; 1423 1424 /* Cache the primary path address here, when we 1425 * need a an address for msg_name. 1426 */ 1427 union sctp_addr primary_addr; 1428 1429 /* active_path 1430 * The path that we are currently using to 1431 * transmit new data and most control chunks. 1432 */ 1433 struct sctp_transport *active_path; 1434 1435 /* retran_path 1436 * 1437 * RFC2960 6.4 Multi-homed SCTP Endpoints 1438 * ... 1439 * Furthermore, when its peer is multi-homed, an 1440 * endpoint SHOULD try to retransmit a chunk to an 1441 * active destination transport address that is 1442 * different from the last destination address to 1443 * which the DATA chunk was sent. 1444 */ 1445 struct sctp_transport *retran_path; 1446 1447 /* Pointer to last transport I have sent on. */ 1448 struct sctp_transport *last_sent_to; 1449 1450 /* This is the last transport I have received DATA on. */ 1451 struct sctp_transport *last_data_from; 1452 1453 /* 1454 * Mapping An array of bits or bytes indicating which out of 1455 * Array order TSN's have been received (relative to the 1456 * Last Rcvd TSN). If no gaps exist, i.e. no out of 1457 * order packets have been received, this array 1458 * will be set to all zero. This structure may be 1459 * in the form of a circular buffer or bit array. 1460 * 1461 * Last Rcvd : This is the last TSN received in 1462 * TSN : sequence. This value is set initially by 1463 * : taking the peer's Initial TSN, received in 1464 * : the INIT or INIT ACK chunk, and subtracting 1465 * : one from it. 1466 * 1467 * Throughout most of the specification this is called the 1468 * "Cumulative TSN ACK Point". In this case, we 1469 * ignore the advice in 12.2 in favour of the term 1470 * used in the bulk of the text. This value is hidden 1471 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn(). 1472 */ 1473 struct sctp_tsnmap tsn_map; 1474 1475 /* This mask is used to disable sending the ASCONF chunk 1476 * with specified parameter to peer. 1477 */ 1478 __be16 addip_disabled_mask; 1479 1480 /* These are capabilities which our peer advertised. */ 1481 __u8 ecn_capable:1, /* Can peer do ECN? */ 1482 ipv4_address:1, /* Peer understands IPv4 addresses? */ 1483 ipv6_address:1, /* Peer understands IPv6 addresses? */ 1484 hostname_address:1, /* Peer understands DNS addresses? */ 1485 asconf_capable:1, /* Does peer support ADDIP? */ 1486 prsctp_capable:1, /* Can peer do PR-SCTP? */ 1487 auth_capable:1; /* Is peer doing SCTP-AUTH? */ 1488 1489 /* sack_needed : This flag indicates if the next received 1490 * : packet is to be responded to with a 1491 * : SACK. This is initialized to 0. When a packet 1492 * : is received sack_cnt is incremented. If this value 1493 * : reaches 2 or more, a SACK is sent and the 1494 * : value is reset to 0. Note: This is used only 1495 * : when no DATA chunks are received out of 1496 * : order. When DATA chunks are out of order, 1497 * : SACK's are not delayed (see Section 6). 1498 */ 1499 __u8 sack_needed:1, /* Do we need to sack the peer? */ 1500 sack_generation:1, 1501 zero_window_announced:1; 1502 __u32 sack_cnt; 1503 1504 __u32 adaptation_ind; /* Adaptation Code point. */ 1505 1506 struct sctp_inithdr_host i; 1507 void *cookie; 1508 int cookie_len; 1509 1510 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. 1511 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the 1512 * Initial TSN Value minus 1 1513 */ 1514 __u32 addip_serial; 1515 1516 /* SCTP-AUTH: We need to know pears random number, hmac list 1517 * and authenticated chunk list. All that is part of the 1518 * cookie and these are just pointers to those locations 1519 */ 1520 sctp_random_param_t *peer_random; 1521 sctp_chunks_param_t *peer_chunks; 1522 sctp_hmac_algo_param_t *peer_hmacs; 1523 } peer; 1524 1525 /* State : A state variable indicating what state the 1526 * : association is in, i.e. COOKIE-WAIT, 1527 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING, 1528 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT. 1529 * 1530 * Note: No "CLOSED" state is illustrated since if a 1531 * association is "CLOSED" its TCB SHOULD be removed. 1532 * 1533 * In this implementation we DO have a CLOSED 1534 * state which is used during initiation and shutdown. 1535 * 1536 * State takes values from SCTP_STATE_*. 1537 */ 1538 sctp_state_t state; 1539 1540 /* Overall : The overall association error count. 1541 * Error Count : [Clear this any time I get something.] 1542 */ 1543 int overall_error_count; 1544 1545 /* The cookie life I award for any cookie. */ 1546 ktime_t cookie_life; 1547 1548 /* These are the association's initial, max, and min RTO values. 1549 * These values will be initialized by system defaults, but can 1550 * be modified via the SCTP_RTOINFO socket option. 1551 */ 1552 unsigned long rto_initial; 1553 unsigned long rto_max; 1554 unsigned long rto_min; 1555 1556 /* Maximum number of new data packets that can be sent in a burst. */ 1557 int max_burst; 1558 1559 /* This is the max_retrans value for the association. This value will 1560 * be initialized initialized from system defaults, but can be 1561 * modified by the SCTP_ASSOCINFO socket option. 1562 */ 1563 int max_retrans; 1564 1565 /* This is the partially failed retrans value for the transport 1566 * and will be initialized from the assocs value. This can be 1567 * changed using the SCTP_PEER_ADDR_THLDS socket option 1568 */ 1569 int pf_retrans; 1570 1571 /* Maximum number of times the endpoint will retransmit INIT */ 1572 __u16 max_init_attempts; 1573 1574 /* How many times have we resent an INIT? */ 1575 __u16 init_retries; 1576 1577 /* The largest timeout or RTO value to use in attempting an INIT */ 1578 unsigned long max_init_timeo; 1579 1580 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 1581 * the destination address every heartbeat interval. This value 1582 * will be inherited by all new transports. 1583 */ 1584 unsigned long hbinterval; 1585 1586 /* This is the max_retrans value for new transports in the 1587 * association. 1588 */ 1589 __u16 pathmaxrxt; 1590 1591 /* Flag that path mtu update is pending */ 1592 __u8 pmtu_pending; 1593 1594 /* Association : The smallest PMTU discovered for all of the 1595 * PMTU : peer's transport addresses. 1596 */ 1597 __u32 pathmtu; 1598 1599 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 1600 __u32 param_flags; 1601 1602 __u32 sackfreq; 1603 /* SACK delay timeout */ 1604 unsigned long sackdelay; 1605 1606 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES]; 1607 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES]; 1608 1609 /* Transport to which SHUTDOWN chunk was last sent. */ 1610 struct sctp_transport *shutdown_last_sent_to; 1611 1612 /* Transport to which INIT chunk was last sent. */ 1613 struct sctp_transport *init_last_sent_to; 1614 1615 /* How many times have we resent a SHUTDOWN */ 1616 int shutdown_retries; 1617 1618 /* Next TSN : The next TSN number to be assigned to a new 1619 * : DATA chunk. This is sent in the INIT or INIT 1620 * : ACK chunk to the peer and incremented each 1621 * : time a DATA chunk is assigned a TSN 1622 * : (normally just prior to transmit or during 1623 * : fragmentation). 1624 */ 1625 __u32 next_tsn; 1626 1627 /* 1628 * Last Rcvd : This is the last TSN received in sequence. This value 1629 * TSN : is set initially by taking the peer's Initial TSN, 1630 * : received in the INIT or INIT ACK chunk, and 1631 * : subtracting one from it. 1632 * 1633 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point. 1634 */ 1635 1636 __u32 ctsn_ack_point; 1637 1638 /* PR-SCTP Advanced.Peer.Ack.Point */ 1639 __u32 adv_peer_ack_point; 1640 1641 /* Highest TSN that is acknowledged by incoming SACKs. */ 1642 __u32 highest_sacked; 1643 1644 /* TSN marking the fast recovery exit point */ 1645 __u32 fast_recovery_exit; 1646 1647 /* Flag to track the current fast recovery state */ 1648 __u8 fast_recovery; 1649 1650 /* The number of unacknowledged data chunks. Reported through 1651 * the SCTP_STATUS sockopt. 1652 */ 1653 __u16 unack_data; 1654 1655 /* The total number of data chunks that we've had to retransmit 1656 * as the result of a T3 timer expiration 1657 */ 1658 __u32 rtx_data_chunks; 1659 1660 /* This is the association's receive buffer space. This value is used 1661 * to set a_rwnd field in an INIT or a SACK chunk. 1662 */ 1663 __u32 rwnd; 1664 1665 /* This is the last advertised value of rwnd over a SACK chunk. */ 1666 __u32 a_rwnd; 1667 1668 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed 1669 * to slop over a maximum of the association's frag_point. 1670 */ 1671 __u32 rwnd_over; 1672 1673 /* Keeps treack of rwnd pressure. This happens when we have 1674 * a window, but not recevie buffer (i.e small packets). This one 1675 * is releases slowly (1 PMTU at a time ). 1676 */ 1677 __u32 rwnd_press; 1678 1679 /* This is the sndbuf size in use for the association. 1680 * This corresponds to the sndbuf size for the association, 1681 * as specified in the sk->sndbuf. 1682 */ 1683 int sndbuf_used; 1684 1685 /* This is the amount of memory that this association has allocated 1686 * in the receive path at any given time. 1687 */ 1688 atomic_t rmem_alloc; 1689 1690 /* This is the wait queue head for send requests waiting on 1691 * the association sndbuf space. 1692 */ 1693 wait_queue_head_t wait; 1694 1695 /* The message size at which SCTP fragmentation will occur. */ 1696 __u32 frag_point; 1697 __u32 user_frag; 1698 1699 /* Counter used to count INIT errors. */ 1700 int init_err_counter; 1701 1702 /* Count the number of INIT cycles (for doubling timeout). */ 1703 int init_cycle; 1704 1705 /* Default send parameters. */ 1706 __u16 default_stream; 1707 __u16 default_flags; 1708 __u32 default_ppid; 1709 __u32 default_context; 1710 __u32 default_timetolive; 1711 1712 /* Default receive parameters */ 1713 __u32 default_rcv_context; 1714 1715 /* This tracks outbound ssn for a given stream. */ 1716 struct sctp_ssnmap *ssnmap; 1717 1718 /* All outbound chunks go through this structure. */ 1719 struct sctp_outq outqueue; 1720 1721 /* A smart pipe that will handle reordering and fragmentation, 1722 * as well as handle passing events up to the ULP. 1723 */ 1724 struct sctp_ulpq ulpq; 1725 1726 /* Last TSN that caused an ECNE Chunk to be sent. */ 1727 __u32 last_ecne_tsn; 1728 1729 /* Last TSN that caused a CWR Chunk to be sent. */ 1730 __u32 last_cwr_tsn; 1731 1732 /* How many duplicated TSNs have we seen? */ 1733 int numduptsns; 1734 1735 /* These are to support 1736 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses 1737 * and Enforcement of Flow and Message Limits" 1738 * <draft-ietf-tsvwg-addip-sctp-02.txt> 1739 * or "ADDIP" for short. 1740 */ 1741 1742 1743 1744 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1745 * 1746 * R1) One and only one ASCONF Chunk MAY be in transit and 1747 * unacknowledged at any one time. If a sender, after sending 1748 * an ASCONF chunk, decides it needs to transfer another 1749 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1750 * returns from the previous ASCONF Chunk before sending a 1751 * subsequent ASCONF. Note this restriction binds each side, 1752 * so at any time two ASCONF may be in-transit on any given 1753 * association (one sent from each endpoint). 1754 * 1755 * [This is our one-and-only-one ASCONF in flight. If we do 1756 * not have an ASCONF in flight, this is NULL.] 1757 */ 1758 struct sctp_chunk *addip_last_asconf; 1759 1760 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk. 1761 * 1762 * This is needed to implement itmes E1 - E4 of the updated 1763 * spec. Here is the justification: 1764 * 1765 * Since the peer may bundle multiple ASCONF chunks toward us, 1766 * we now need the ability to cache multiple ACKs. The section 1767 * describes in detail how they are cached and cleaned up. 1768 */ 1769 struct list_head asconf_ack_list; 1770 1771 /* These ASCONF chunks are waiting to be sent. 1772 * 1773 * These chunaks can't be pushed to outqueue until receiving 1774 * ASCONF_ACK for the previous ASCONF indicated by 1775 * addip_last_asconf, so as to guarantee that only one ASCONF 1776 * is in flight at any time. 1777 * 1778 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1779 * 1780 * In defining the ASCONF Chunk transfer procedures, it is 1781 * essential that these transfers MUST NOT cause congestion 1782 * within the network. To achieve this, we place these 1783 * restrictions on the transfer of ASCONF Chunks: 1784 * 1785 * R1) One and only one ASCONF Chunk MAY be in transit and 1786 * unacknowledged at any one time. If a sender, after sending 1787 * an ASCONF chunk, decides it needs to transfer another 1788 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1789 * returns from the previous ASCONF Chunk before sending a 1790 * subsequent ASCONF. Note this restriction binds each side, 1791 * so at any time two ASCONF may be in-transit on any given 1792 * association (one sent from each endpoint). 1793 * 1794 * 1795 * [I really think this is EXACTLY the sort of intelligence 1796 * which already resides in sctp_outq. Please move this 1797 * queue and its supporting logic down there. --piggy] 1798 */ 1799 struct list_head addip_chunk_list; 1800 1801 /* ADDIP Section 4.1 ASCONF Chunk Procedures 1802 * 1803 * A2) A serial number should be assigned to the Chunk. The 1804 * serial number SHOULD be a monotonically increasing 1805 * number. The serial number SHOULD be initialized at 1806 * the start of the association to the same value as the 1807 * Initial TSN and every time a new ASCONF chunk is created 1808 * it is incremented by one after assigning the serial number 1809 * to the newly created chunk. 1810 * 1811 * ADDIP 1812 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF) 1813 * 1814 * Serial Number : 32 bits (unsigned integer) 1815 * 1816 * This value represents a Serial Number for the ASCONF 1817 * Chunk. The valid range of Serial Number is from 0 to 1818 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0 1819 * after reaching 4294967295. 1820 */ 1821 __u32 addip_serial; 1822 int src_out_of_asoc_ok; 1823 union sctp_addr *asconf_addr_del_pending; 1824 struct sctp_transport *new_transport; 1825 1826 /* SCTP AUTH: list of the endpoint shared keys. These 1827 * keys are provided out of band by the user applicaton 1828 * and can't change during the lifetime of the association 1829 */ 1830 struct list_head endpoint_shared_keys; 1831 1832 /* SCTP AUTH: 1833 * The current generated assocaition shared key (secret) 1834 */ 1835 struct sctp_auth_bytes *asoc_shared_key; 1836 1837 /* SCTP AUTH: hmac id of the first peer requested algorithm 1838 * that we support. 1839 */ 1840 __u16 default_hmac_id; 1841 1842 __u16 active_key_id; 1843 1844 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */ 1845 temp:1; /* Is it a temporary association? */ 1846 1847 struct sctp_priv_assoc_stats stats; 1848}; 1849 1850 1851/* An eyecatcher for determining if we are really looking at an 1852 * association data structure. 1853 */ 1854enum { 1855 SCTP_ASSOC_EYECATCHER = 0xa550c123, 1856}; 1857 1858/* Recover the outter association structure. */ 1859static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base) 1860{ 1861 struct sctp_association *asoc; 1862 1863 asoc = container_of(base, struct sctp_association, base); 1864 return asoc; 1865} 1866 1867/* These are function signatures for manipulating associations. */ 1868 1869 1870struct sctp_association * 1871sctp_association_new(const struct sctp_endpoint *, const struct sock *, 1872 sctp_scope_t scope, gfp_t gfp); 1873void sctp_association_free(struct sctp_association *); 1874void sctp_association_put(struct sctp_association *); 1875void sctp_association_hold(struct sctp_association *); 1876 1877struct sctp_transport *sctp_assoc_choose_alter_transport( 1878 struct sctp_association *, struct sctp_transport *); 1879void sctp_assoc_update_retran_path(struct sctp_association *); 1880struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *, 1881 const union sctp_addr *); 1882int sctp_assoc_lookup_laddr(struct sctp_association *asoc, 1883 const union sctp_addr *laddr); 1884struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *, 1885 const union sctp_addr *address, 1886 const gfp_t gfp, 1887 const int peer_state); 1888void sctp_assoc_del_peer(struct sctp_association *asoc, 1889 const union sctp_addr *addr); 1890void sctp_assoc_rm_peer(struct sctp_association *asoc, 1891 struct sctp_transport *peer); 1892void sctp_assoc_control_transport(struct sctp_association *, 1893 struct sctp_transport *, 1894 sctp_transport_cmd_t, sctp_sn_error_t); 1895struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32); 1896struct sctp_transport *sctp_assoc_is_match(struct sctp_association *, 1897 struct net *, 1898 const union sctp_addr *, 1899 const union sctp_addr *); 1900void sctp_assoc_migrate(struct sctp_association *, struct sock *); 1901void sctp_assoc_update(struct sctp_association *old, 1902 struct sctp_association *new); 1903 1904__u32 sctp_association_get_next_tsn(struct sctp_association *); 1905 1906void sctp_assoc_sync_pmtu(struct sock *, struct sctp_association *); 1907void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int); 1908void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int); 1909void sctp_assoc_set_primary(struct sctp_association *, 1910 struct sctp_transport *); 1911void sctp_assoc_del_nonprimary_peers(struct sctp_association *, 1912 struct sctp_transport *); 1913int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *, 1914 sctp_scope_t, gfp_t); 1915int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *, 1916 struct sctp_cookie*, 1917 gfp_t gfp); 1918int sctp_assoc_set_id(struct sctp_association *, gfp_t); 1919void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc); 1920struct sctp_chunk *sctp_assoc_lookup_asconf_ack( 1921 const struct sctp_association *asoc, 1922 __be32 serial); 1923void sctp_asconf_queue_teardown(struct sctp_association *asoc); 1924 1925int sctp_cmp_addr_exact(const union sctp_addr *ss1, 1926 const union sctp_addr *ss2); 1927struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc); 1928 1929/* A convenience structure to parse out SCTP specific CMSGs. */ 1930typedef struct sctp_cmsgs { 1931 struct sctp_initmsg *init; 1932 struct sctp_sndrcvinfo *srinfo; 1933 struct sctp_sndinfo *sinfo; 1934} sctp_cmsgs_t; 1935 1936/* Structure for tracking memory objects */ 1937typedef struct { 1938 char *label; 1939 atomic_t *counter; 1940} sctp_dbg_objcnt_entry_t; 1941 1942#endif /* __sctp_structs_h__ */ 1943