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