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