1 /* SCTP kernel implementation 2 * (C) Copyright IBM Corp. 2001, 2004 3 * Copyright (c) 1999-2000 Cisco, Inc. 4 * Copyright (c) 1999-2001 Motorola, Inc. 5 * Copyright (c) 2001 Intel Corp. 6 * 7 * This file is part of the SCTP kernel implementation 8 * 9 * This SCTP implementation is free software; 10 * you can redistribute it and/or modify it under the terms of 11 * the GNU General Public License as published by 12 * the Free Software Foundation; either version 2, or (at your option) 13 * any later version. 14 * 15 * This SCTP implementation is distributed in the hope that it 16 * will be useful, but WITHOUT ANY WARRANTY; without even the implied 17 * ************************ 18 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 19 * See the GNU General Public License for more details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with GNU CC; see the file COPYING. If not, see 23 * <http://www.gnu.org/licenses/>. 24 * 25 * Please send any bug reports or fixes you make to the 26 * email addresses: 27 * lksctp developers <linux-sctp@vger.kernel.org> 28 * 29 * Written or modified by: 30 * Randall Stewart <randall@sctp.chicago.il.us> 31 * Ken Morneau <kmorneau@cisco.com> 32 * Qiaobing Xie <qxie1@email.mot.com> 33 * La Monte H.P. Yarroll <piggy@acm.org> 34 * Karl Knutson <karl@athena.chicago.il.us> 35 * Jon Grimm <jgrimm@us.ibm.com> 36 * Xingang Guo <xingang.guo@intel.com> 37 * Hui Huang <hui.huang@nokia.com> 38 * Sridhar Samudrala <sri@us.ibm.com> 39 * Daisy Chang <daisyc@us.ibm.com> 40 * Dajiang Zhang <dajiang.zhang@nokia.com> 41 * Ardelle Fan <ardelle.fan@intel.com> 42 * Ryan Layer <rmlayer@us.ibm.com> 43 * Anup Pemmaiah <pemmaiah@cc.usu.edu> 44 * Kevin Gao <kevin.gao@intel.com> 45 */ 46 47 #ifndef __sctp_structs_h__ 48 #define __sctp_structs_h__ 49 50 #include <linux/ktime.h> 51 #include <linux/rhashtable-types.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/flex_array.h> /* We need flex_array. */ 61 #include <linux/sctp.h> /* We need sctp* header structs. */ 62 #include <net/sctp/auth.h> /* We need auth specific structs */ 63 #include <net/ip.h> /* For inet_skb_parm */ 64 65 /* A convenience structure for handling sockaddr structures. 66 * We should wean ourselves off this. 67 */ 68 union sctp_addr { 69 struct sockaddr_in v4; 70 struct sockaddr_in6 v6; 71 struct sockaddr sa; 72 }; 73 74 /* Forward declarations for data structures. */ 75 struct sctp_globals; 76 struct sctp_endpoint; 77 struct sctp_association; 78 struct sctp_transport; 79 struct sctp_packet; 80 struct sctp_chunk; 81 struct sctp_inq; 82 struct sctp_outq; 83 struct sctp_bind_addr; 84 struct sctp_ulpq; 85 struct sctp_ep_common; 86 struct crypto_shash; 87 struct sctp_stream; 88 89 90 #include <net/sctp/tsnmap.h> 91 #include <net/sctp/ulpevent.h> 92 #include <net/sctp/ulpqueue.h> 93 #include <net/sctp/stream_interleave.h> 94 95 /* Structures useful for managing bind/connect. */ 96 97 struct sctp_bind_bucket { 98 unsigned short port; 99 unsigned short fastreuse; 100 struct hlist_node node; 101 struct hlist_head owner; 102 struct net *net; 103 }; 104 105 struct sctp_bind_hashbucket { 106 spinlock_t lock; 107 struct hlist_head chain; 108 }; 109 110 /* Used for hashing all associations. */ 111 struct sctp_hashbucket { 112 rwlock_t lock; 113 struct hlist_head chain; 114 } __attribute__((__aligned__(8))); 115 116 117 /* The SCTP globals structure. */ 118 extern struct sctp_globals { 119 /* This is a list of groups of functions for each address 120 * family that we support. 121 */ 122 struct list_head address_families; 123 124 /* This is the hash of all endpoints. */ 125 struct sctp_hashbucket *ep_hashtable; 126 /* This is the sctp port control hash. */ 127 struct sctp_bind_hashbucket *port_hashtable; 128 /* This is the hash of all transports. */ 129 struct rhltable transport_hashtable; 130 131 /* Sizes of above hashtables. */ 132 int ep_hashsize; 133 int port_hashsize; 134 135 /* Default initialization values to be applied to new associations. */ 136 __u16 max_instreams; 137 __u16 max_outstreams; 138 139 /* Flag to indicate whether computing and verifying checksum 140 * is disabled. */ 141 bool checksum_disable; 142 } sctp_globals; 143 144 #define sctp_max_instreams (sctp_globals.max_instreams) 145 #define sctp_max_outstreams (sctp_globals.max_outstreams) 146 #define sctp_address_families (sctp_globals.address_families) 147 #define sctp_ep_hashsize (sctp_globals.ep_hashsize) 148 #define sctp_ep_hashtable (sctp_globals.ep_hashtable) 149 #define sctp_port_hashsize (sctp_globals.port_hashsize) 150 #define sctp_port_hashtable (sctp_globals.port_hashtable) 151 #define sctp_transport_hashtable (sctp_globals.transport_hashtable) 152 #define sctp_checksum_disable (sctp_globals.checksum_disable) 153 154 /* SCTP Socket type: UDP or TCP style. */ 155 enum sctp_socket_type { 156 SCTP_SOCKET_UDP = 0, 157 SCTP_SOCKET_UDP_HIGH_BANDWIDTH, 158 SCTP_SOCKET_TCP 159 }; 160 161 /* Per socket SCTP information. */ 162 struct sctp_sock { 163 /* inet_sock has to be the first member of sctp_sock */ 164 struct inet_sock inet; 165 /* What kind of a socket is this? */ 166 enum sctp_socket_type type; 167 168 /* PF_ family specific functions. */ 169 struct sctp_pf *pf; 170 171 /* Access to HMAC transform. */ 172 struct crypto_shash *hmac; 173 char *sctp_hmac_alg; 174 175 /* What is our base endpointer? */ 176 struct sctp_endpoint *ep; 177 178 struct sctp_bind_bucket *bind_hash; 179 /* Various Socket Options. */ 180 __u16 default_stream; 181 __u32 default_ppid; 182 __u16 default_flags; 183 __u32 default_context; 184 __u32 default_timetolive; 185 __u32 default_rcv_context; 186 int max_burst; 187 188 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 189 * the destination address every heartbeat interval. This value 190 * will be inherited by all new associations. 191 */ 192 __u32 hbinterval; 193 194 /* This is the max_retrans value for new associations. */ 195 __u16 pathmaxrxt; 196 197 __u32 flowlabel; 198 __u8 dscp; 199 200 /* The initial Path MTU to use for new associations. */ 201 __u32 pathmtu; 202 203 /* The default SACK delay timeout for new associations. */ 204 __u32 sackdelay; 205 __u32 sackfreq; 206 207 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 208 __u32 param_flags; 209 210 struct sctp_rtoinfo rtoinfo; 211 struct sctp_paddrparams paddrparam; 212 struct sctp_assocparams assocparams; 213 214 /* 215 * These two structures must be grouped together for the usercopy 216 * whitelist region. 217 */ 218 struct sctp_event_subscribe subscribe; 219 struct sctp_initmsg initmsg; 220 221 int user_frag; 222 223 __u32 autoclose; 224 __u32 adaptation_ind; 225 __u32 pd_point; 226 __u16 nodelay:1, 227 reuse:1, 228 disable_fragments:1, 229 v4mapped:1, 230 frag_interleave:1, 231 strm_interleave:1, 232 recvrcvinfo:1, 233 recvnxtinfo:1, 234 data_ready_signalled:1; 235 236 atomic_t pd_mode; 237 /* Receive to here while partial delivery is in effect. */ 238 struct sk_buff_head pd_lobby; 239 240 /* These must be the last fields, as they will skipped on copies, 241 * like on accept and peeloff operations 242 */ 243 struct list_head auto_asconf_list; 244 int do_auto_asconf; 245 }; 246 247 static inline struct sctp_sock *sctp_sk(const struct sock *sk) 248 { 249 return (struct sctp_sock *)sk; 250 } 251 252 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp) 253 { 254 return (struct sock *)sp; 255 } 256 257 #if IS_ENABLED(CONFIG_IPV6) 258 struct sctp6_sock { 259 struct sctp_sock sctp; 260 struct ipv6_pinfo inet6; 261 }; 262 #endif /* CONFIG_IPV6 */ 263 264 265 /* This is our APPLICATION-SPECIFIC state cookie. 266 * THIS IS NOT DICTATED BY THE SPECIFICATION. 267 */ 268 /* These are the parts of an association which we send in the cookie. 269 * Most of these are straight out of: 270 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB) 271 * 272 */ 273 274 struct sctp_cookie { 275 276 /* My : Tag expected in every inbound packet and sent 277 * Verification: in the INIT or INIT ACK chunk. 278 * Tag : 279 */ 280 __u32 my_vtag; 281 282 /* Peer's : Tag expected in every outbound packet except 283 * Verification: in the INIT chunk. 284 * Tag : 285 */ 286 __u32 peer_vtag; 287 288 /* The rest of these are not from the spec, but really need to 289 * be in the cookie. 290 */ 291 292 /* My Tie Tag : Assist in discovering a restarting association. */ 293 __u32 my_ttag; 294 295 /* Peer's Tie Tag: Assist in discovering a restarting association. */ 296 __u32 peer_ttag; 297 298 /* When does this cookie expire? */ 299 ktime_t expiration; 300 301 /* Number of inbound/outbound streams which are set 302 * and negotiated during the INIT process. 303 */ 304 __u16 sinit_num_ostreams; 305 __u16 sinit_max_instreams; 306 307 /* This is the first sequence number I used. */ 308 __u32 initial_tsn; 309 310 /* This holds the originating address of the INIT packet. */ 311 union sctp_addr peer_addr; 312 313 /* IG Section 2.35.3 314 * Include the source port of the INIT-ACK 315 */ 316 __u16 my_port; 317 318 __u8 prsctp_capable; 319 320 /* Padding for future use */ 321 __u8 padding; 322 323 __u32 adaptation_ind; 324 325 __u8 auth_random[sizeof(struct sctp_paramhdr) + 326 SCTP_AUTH_RANDOM_LENGTH]; 327 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2]; 328 __u8 auth_chunks[sizeof(struct sctp_paramhdr) + SCTP_AUTH_MAX_CHUNKS]; 329 330 /* This is a shim for my peer's INIT packet, followed by 331 * a copy of the raw address list of the association. 332 * The length of the raw address list is saved in the 333 * raw_addr_list_len field, which will be used at the time when 334 * the association TCB is re-constructed from the cookie. 335 */ 336 __u32 raw_addr_list_len; 337 struct sctp_init_chunk peer_init[0]; 338 }; 339 340 341 /* The format of our cookie that we send to our peer. */ 342 struct sctp_signed_cookie { 343 __u8 signature[SCTP_SECRET_SIZE]; 344 __u32 __pad; /* force sctp_cookie alignment to 64 bits */ 345 struct sctp_cookie c; 346 } __packed; 347 348 /* This is another convenience type to allocate memory for address 349 * params for the maximum size and pass such structures around 350 * internally. 351 */ 352 union sctp_addr_param { 353 struct sctp_paramhdr p; 354 struct sctp_ipv4addr_param v4; 355 struct sctp_ipv6addr_param v6; 356 }; 357 358 /* A convenience type to allow walking through the various 359 * parameters and avoid casting all over the place. 360 */ 361 union sctp_params { 362 void *v; 363 struct sctp_paramhdr *p; 364 struct sctp_cookie_preserve_param *life; 365 struct sctp_hostname_param *dns; 366 struct sctp_cookie_param *cookie; 367 struct sctp_supported_addrs_param *sat; 368 struct sctp_ipv4addr_param *v4; 369 struct sctp_ipv6addr_param *v6; 370 union sctp_addr_param *addr; 371 struct sctp_adaptation_ind_param *aind; 372 struct sctp_supported_ext_param *ext; 373 struct sctp_random_param *random; 374 struct sctp_chunks_param *chunks; 375 struct sctp_hmac_algo_param *hmac_algo; 376 struct sctp_addip_param *addip; 377 }; 378 379 /* RFC 2960. Section 3.3.5 Heartbeat. 380 * Heartbeat Information: variable length 381 * The Sender-specific Heartbeat Info field should normally include 382 * information about the sender's current time when this HEARTBEAT 383 * chunk is sent and the destination transport address to which this 384 * HEARTBEAT is sent (see Section 8.3). 385 */ 386 struct sctp_sender_hb_info { 387 struct sctp_paramhdr param_hdr; 388 union sctp_addr daddr; 389 unsigned long sent_at; 390 __u64 hb_nonce; 391 }; 392 393 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt, 394 gfp_t gfp); 395 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid); 396 void sctp_stream_free(struct sctp_stream *stream); 397 void sctp_stream_clear(struct sctp_stream *stream); 398 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new); 399 400 /* What is the current SSN number for this stream? */ 401 #define sctp_ssn_peek(stream, type, sid) \ 402 (sctp_stream_##type((stream), (sid))->ssn) 403 404 /* Return the next SSN number for this stream. */ 405 #define sctp_ssn_next(stream, type, sid) \ 406 (sctp_stream_##type((stream), (sid))->ssn++) 407 408 /* Skip over this ssn and all below. */ 409 #define sctp_ssn_skip(stream, type, sid, ssn) \ 410 (sctp_stream_##type((stream), (sid))->ssn = ssn + 1) 411 412 /* What is the current MID number for this stream? */ 413 #define sctp_mid_peek(stream, type, sid) \ 414 (sctp_stream_##type((stream), (sid))->mid) 415 416 /* Return the next MID number for this stream. */ 417 #define sctp_mid_next(stream, type, sid) \ 418 (sctp_stream_##type((stream), (sid))->mid++) 419 420 /* Skip over this mid and all below. */ 421 #define sctp_mid_skip(stream, type, sid, mid) \ 422 (sctp_stream_##type((stream), (sid))->mid = mid + 1) 423 424 /* What is the current MID_uo number for this stream? */ 425 #define sctp_mid_uo_peek(stream, type, sid) \ 426 (sctp_stream_##type((stream), (sid))->mid_uo) 427 428 /* Return the next MID_uo number for this stream. */ 429 #define sctp_mid_uo_next(stream, type, sid) \ 430 (sctp_stream_##type((stream), (sid))->mid_uo++) 431 432 /* 433 * Pointers to address related SCTP functions. 434 * (i.e. things that depend on the address family.) 435 */ 436 struct sctp_af { 437 int (*sctp_xmit) (struct sk_buff *skb, 438 struct sctp_transport *); 439 int (*setsockopt) (struct sock *sk, 440 int level, 441 int optname, 442 char __user *optval, 443 unsigned int optlen); 444 int (*getsockopt) (struct sock *sk, 445 int level, 446 int optname, 447 char __user *optval, 448 int __user *optlen); 449 int (*compat_setsockopt) (struct sock *sk, 450 int level, 451 int optname, 452 char __user *optval, 453 unsigned int optlen); 454 int (*compat_getsockopt) (struct sock *sk, 455 int level, 456 int optname, 457 char __user *optval, 458 int __user *optlen); 459 void (*get_dst) (struct sctp_transport *t, 460 union sctp_addr *saddr, 461 struct flowi *fl, 462 struct sock *sk); 463 void (*get_saddr) (struct sctp_sock *sk, 464 struct sctp_transport *t, 465 struct flowi *fl); 466 void (*copy_addrlist) (struct list_head *, 467 struct net_device *); 468 int (*cmp_addr) (const union sctp_addr *addr1, 469 const union sctp_addr *addr2); 470 void (*addr_copy) (union sctp_addr *dst, 471 union sctp_addr *src); 472 void (*from_skb) (union sctp_addr *, 473 struct sk_buff *skb, 474 int saddr); 475 void (*from_sk) (union sctp_addr *, 476 struct sock *sk); 477 void (*from_addr_param) (union sctp_addr *, 478 union sctp_addr_param *, 479 __be16 port, int iif); 480 int (*to_addr_param) (const union sctp_addr *, 481 union sctp_addr_param *); 482 int (*addr_valid) (union sctp_addr *, 483 struct sctp_sock *, 484 const struct sk_buff *); 485 enum sctp_scope (*scope)(union sctp_addr *); 486 void (*inaddr_any) (union sctp_addr *, __be16); 487 int (*is_any) (const union sctp_addr *); 488 int (*available) (union sctp_addr *, 489 struct sctp_sock *); 490 int (*skb_iif) (const struct sk_buff *sk); 491 int (*is_ce) (const struct sk_buff *sk); 492 void (*seq_dump_addr)(struct seq_file *seq, 493 union sctp_addr *addr); 494 void (*ecn_capable)(struct sock *sk); 495 __u16 net_header_len; 496 int sockaddr_len; 497 int (*ip_options_len)(struct sock *sk); 498 sa_family_t sa_family; 499 struct list_head list; 500 }; 501 502 struct sctp_af *sctp_get_af_specific(sa_family_t); 503 int sctp_register_af(struct sctp_af *); 504 505 /* Protocol family functions. */ 506 struct sctp_pf { 507 void (*event_msgname)(struct sctp_ulpevent *, char *, int *); 508 void (*skb_msgname) (struct sk_buff *, char *, int *); 509 int (*af_supported) (sa_family_t, struct sctp_sock *); 510 int (*cmp_addr) (const union sctp_addr *, 511 const union sctp_addr *, 512 struct sctp_sock *); 513 int (*bind_verify) (struct sctp_sock *, union sctp_addr *); 514 int (*send_verify) (struct sctp_sock *, union sctp_addr *); 515 int (*supported_addrs)(const struct sctp_sock *, __be16 *); 516 struct sock *(*create_accept_sk) (struct sock *sk, 517 struct sctp_association *asoc, 518 bool kern); 519 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr); 520 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk); 521 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk); 522 void (*copy_ip_options)(struct sock *sk, struct sock *newsk); 523 struct sctp_af *af; 524 }; 525 526 527 /* Structure to track chunk fragments that have been acked, but peer 528 * fragments of the same message have not. 529 */ 530 struct sctp_datamsg { 531 /* Chunks waiting to be submitted to lower layer. */ 532 struct list_head chunks; 533 /* Reference counting. */ 534 refcount_t refcnt; 535 /* When is this message no longer interesting to the peer? */ 536 unsigned long expires_at; 537 /* Did the messenge fail to send? */ 538 int send_error; 539 u8 send_failed:1, 540 can_delay:1, /* should this message be Nagle delayed */ 541 abandoned:1; /* should this message be abandoned */ 542 }; 543 544 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *, 545 struct sctp_sndrcvinfo *, 546 struct iov_iter *); 547 void sctp_datamsg_free(struct sctp_datamsg *); 548 void sctp_datamsg_put(struct sctp_datamsg *); 549 void sctp_chunk_fail(struct sctp_chunk *, int error); 550 int sctp_chunk_abandoned(struct sctp_chunk *); 551 552 /* RFC2960 1.4 Key Terms 553 * 554 * o Chunk: A unit of information within an SCTP packet, consisting of 555 * a chunk header and chunk-specific content. 556 * 557 * As a matter of convenience, we remember the SCTP common header for 558 * each chunk as well as a few other header pointers... 559 */ 560 struct sctp_chunk { 561 struct list_head list; 562 563 refcount_t refcnt; 564 565 /* How many times this chunk have been sent, for prsctp RTX policy */ 566 int sent_count; 567 568 union { 569 /* This is our link to the per-transport transmitted list. */ 570 struct list_head transmitted_list; 571 /* List in specific stream outq */ 572 struct list_head stream_list; 573 }; 574 575 /* This field is used by chunks that hold fragmented data. 576 * For the first fragment this is the list that holds the rest of 577 * fragments. For the remaining fragments, this is the link to the 578 * frag_list maintained in the first fragment. 579 */ 580 struct list_head frag_list; 581 582 /* This points to the sk_buff containing the actual data. */ 583 struct sk_buff *skb; 584 585 union { 586 /* In case of GSO packets, this will store the head one */ 587 struct sk_buff *head_skb; 588 /* In case of auth enabled, this will point to the shkey */ 589 struct sctp_shared_key *shkey; 590 }; 591 592 /* These are the SCTP headers by reverse order in a packet. 593 * Note that some of these may happen more than once. In that 594 * case, we point at the "current" one, whatever that means 595 * for that level of header. 596 */ 597 598 /* We point this at the FIRST TLV parameter to chunk_hdr. */ 599 union sctp_params param_hdr; 600 union { 601 __u8 *v; 602 struct sctp_datahdr *data_hdr; 603 struct sctp_inithdr *init_hdr; 604 struct sctp_sackhdr *sack_hdr; 605 struct sctp_heartbeathdr *hb_hdr; 606 struct sctp_sender_hb_info *hbs_hdr; 607 struct sctp_shutdownhdr *shutdown_hdr; 608 struct sctp_signed_cookie *cookie_hdr; 609 struct sctp_ecnehdr *ecne_hdr; 610 struct sctp_cwrhdr *ecn_cwr_hdr; 611 struct sctp_errhdr *err_hdr; 612 struct sctp_addiphdr *addip_hdr; 613 struct sctp_fwdtsn_hdr *fwdtsn_hdr; 614 struct sctp_authhdr *auth_hdr; 615 struct sctp_idatahdr *idata_hdr; 616 struct sctp_ifwdtsn_hdr *ifwdtsn_hdr; 617 } subh; 618 619 __u8 *chunk_end; 620 621 struct sctp_chunkhdr *chunk_hdr; 622 struct sctphdr *sctp_hdr; 623 624 /* This needs to be recoverable for SCTP_SEND_FAILED events. */ 625 struct sctp_sndrcvinfo sinfo; 626 627 /* Which association does this belong to? */ 628 struct sctp_association *asoc; 629 630 /* What endpoint received this chunk? */ 631 struct sctp_ep_common *rcvr; 632 633 /* We fill this in if we are calculating RTT. */ 634 unsigned long sent_at; 635 636 /* What is the origin IP address for this chunk? */ 637 union sctp_addr source; 638 /* Destination address for this chunk. */ 639 union sctp_addr dest; 640 641 /* For outbound message, track all fragments for SEND_FAILED. */ 642 struct sctp_datamsg *msg; 643 644 /* For an inbound chunk, this tells us where it came from. 645 * For an outbound chunk, it tells us where we'd like it to 646 * go. It is NULL if we have no preference. 647 */ 648 struct sctp_transport *transport; 649 650 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO 651 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH 652 * spec violates the principle premis that all chunks are processed 653 * in order. 654 */ 655 struct sk_buff *auth_chunk; 656 657 #define SCTP_CAN_FRTX 0x0 658 #define SCTP_NEED_FRTX 0x1 659 #define SCTP_DONT_FRTX 0x2 660 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */ 661 has_tsn:1, /* Does this chunk have a TSN yet? */ 662 has_ssn:1, /* Does this chunk have a SSN yet? */ 663 #define has_mid has_ssn 664 singleton:1, /* Only chunk in the packet? */ 665 end_of_packet:1, /* Last chunk in the packet? */ 666 ecn_ce_done:1, /* Have we processed the ECN CE bit? */ 667 pdiscard:1, /* Discard the whole packet now? */ 668 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */ 669 data_accepted:1, /* At least 1 chunk accepted */ 670 auth:1, /* IN: was auth'ed | OUT: needs auth */ 671 has_asconf:1, /* IN: have seen an asconf before */ 672 tsn_missing_report:2, /* Data chunk missing counter. */ 673 fast_retransmit:2; /* Is this chunk fast retransmitted? */ 674 }; 675 676 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1) 677 void sctp_chunk_hold(struct sctp_chunk *); 678 void sctp_chunk_put(struct sctp_chunk *); 679 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len, 680 struct iov_iter *from); 681 void sctp_chunk_free(struct sctp_chunk *); 682 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data); 683 struct sctp_chunk *sctp_chunkify(struct sk_buff *, 684 const struct sctp_association *, 685 struct sock *, gfp_t gfp); 686 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *, 687 union sctp_addr *); 688 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk); 689 690 static inline __u16 sctp_chunk_stream_no(struct sctp_chunk *ch) 691 { 692 return ntohs(ch->subh.data_hdr->stream); 693 } 694 695 enum { 696 SCTP_ADDR_NEW, /* new address added to assoc/ep */ 697 SCTP_ADDR_SRC, /* address can be used as source */ 698 SCTP_ADDR_DEL, /* address about to be deleted */ 699 }; 700 701 /* This is a structure for holding either an IPv6 or an IPv4 address. */ 702 struct sctp_sockaddr_entry { 703 struct list_head list; 704 struct rcu_head rcu; 705 union sctp_addr a; 706 __u8 state; 707 __u8 valid; 708 }; 709 710 #define SCTP_ADDRESS_TICK_DELAY 500 711 712 /* This structure holds lists of chunks as we are assembling for 713 * transmission. 714 */ 715 struct sctp_packet { 716 /* These are the SCTP header values (host order) for the packet. */ 717 __u16 source_port; 718 __u16 destination_port; 719 __u32 vtag; 720 721 /* This contains the payload chunks. */ 722 struct list_head chunk_list; 723 724 /* This is the overhead of the sctp and ip headers. */ 725 size_t overhead; 726 /* This is the total size of all chunks INCLUDING padding. */ 727 size_t size; 728 /* This is the maximum size this packet may have */ 729 size_t max_size; 730 731 /* The packet is destined for this transport address. 732 * The function we finally use to pass down to the next lower 733 * layer lives in the transport structure. 734 */ 735 struct sctp_transport *transport; 736 737 /* pointer to the auth chunk for this packet */ 738 struct sctp_chunk *auth; 739 740 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */ 741 has_sack:1, /* This packet contains a SACK chunk. */ 742 has_auth:1, /* This packet contains an AUTH chunk */ 743 has_data:1, /* This packet contains at least 1 DATA chunk */ 744 ipfragok:1; /* So let ip fragment this packet */ 745 }; 746 747 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *, 748 __u16 sport, __u16 dport); 749 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int); 750 enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet, 751 struct sctp_chunk *chunk, 752 int one_packet, gfp_t gfp); 753 enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet, 754 struct sctp_chunk *chunk); 755 int sctp_packet_transmit(struct sctp_packet *, gfp_t); 756 void sctp_packet_free(struct sctp_packet *); 757 758 static inline int sctp_packet_empty(struct sctp_packet *packet) 759 { 760 return packet->size == packet->overhead; 761 } 762 763 /* This represents a remote transport address. 764 * For local transport addresses, we just use union sctp_addr. 765 * 766 * RFC2960 Section 1.4 Key Terms 767 * 768 * o Transport address: A Transport Address is traditionally defined 769 * by Network Layer address, Transport Layer protocol and Transport 770 * Layer port number. In the case of SCTP running over IP, a 771 * transport address is defined by the combination of an IP address 772 * and an SCTP port number (where SCTP is the Transport protocol). 773 * 774 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control 775 * 776 * o The sender keeps a separate congestion control parameter set for 777 * each of the destination addresses it can send to (not each 778 * source-destination pair but for each destination). The parameters 779 * should decay if the address is not used for a long enough time 780 * period. 781 * 782 */ 783 struct sctp_transport { 784 /* A list of transports. */ 785 struct list_head transports; 786 struct rhlist_head node; 787 788 /* Reference counting. */ 789 refcount_t refcnt; 790 /* RTO-Pending : A flag used to track if one of the DATA 791 * chunks sent to this address is currently being 792 * used to compute a RTT. If this flag is 0, 793 * the next DATA chunk sent to this destination 794 * should be used to compute a RTT and this flag 795 * should be set. Every time the RTT 796 * calculation completes (i.e. the DATA chunk 797 * is SACK'd) clear this flag. 798 */ 799 __u32 rto_pending:1, 800 801 /* 802 * hb_sent : a flag that signals that we have a pending 803 * heartbeat. 804 */ 805 hb_sent:1, 806 807 /* Is the Path MTU update pending on this tranport */ 808 pmtu_pending:1, 809 810 dst_pending_confirm:1, /* need to confirm neighbour */ 811 812 /* Has this transport moved the ctsn since we last sacked */ 813 sack_generation:1; 814 u32 dst_cookie; 815 816 struct flowi fl; 817 818 /* This is the peer's IP address and port. */ 819 union sctp_addr ipaddr; 820 821 /* These are the functions we call to handle LLP stuff. */ 822 struct sctp_af *af_specific; 823 824 /* Which association do we belong to? */ 825 struct sctp_association *asoc; 826 827 /* RFC2960 828 * 829 * 12.3 Per Transport Address Data 830 * 831 * For each destination transport address in the peer's 832 * address list derived from the INIT or INIT ACK chunk, a 833 * number of data elements needs to be maintained including: 834 */ 835 /* RTO : The current retransmission timeout value. */ 836 unsigned long rto; 837 838 __u32 rtt; /* This is the most recent RTT. */ 839 840 /* RTTVAR : The current RTT variation. */ 841 __u32 rttvar; 842 843 /* SRTT : The current smoothed round trip time. */ 844 __u32 srtt; 845 846 /* 847 * These are the congestion stats. 848 */ 849 /* cwnd : The current congestion window. */ 850 __u32 cwnd; /* This is the actual cwnd. */ 851 852 /* ssthresh : The current slow start threshold value. */ 853 __u32 ssthresh; 854 855 /* partial : The tracking method for increase of cwnd when in 856 * bytes acked : congestion avoidance mode (see Section 6.2.2) 857 */ 858 __u32 partial_bytes_acked; 859 860 /* Data that has been sent, but not acknowledged. */ 861 __u32 flight_size; 862 863 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */ 864 865 /* Destination */ 866 struct dst_entry *dst; 867 /* Source address. */ 868 union sctp_addr saddr; 869 870 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 871 * the destination address every heartbeat interval. 872 */ 873 unsigned long hbinterval; 874 875 /* SACK delay timeout */ 876 unsigned long sackdelay; 877 __u32 sackfreq; 878 879 atomic_t mtu_info; 880 881 /* When was the last time that we heard from this transport? We use 882 * this to pick new active and retran paths. 883 */ 884 ktime_t last_time_heard; 885 886 /* When was the last time that we sent a chunk using this 887 * transport? We use this to check for idle transports 888 */ 889 unsigned long last_time_sent; 890 891 /* Last time(in jiffies) when cwnd is reduced due to the congestion 892 * indication based on ECNE chunk. 893 */ 894 unsigned long last_time_ecne_reduced; 895 896 /* This is the max_retrans value for the transport and will 897 * be initialized from the assocs value. This can be changed 898 * using the SCTP_SET_PEER_ADDR_PARAMS socket option. 899 */ 900 __u16 pathmaxrxt; 901 902 __u32 flowlabel; 903 __u8 dscp; 904 905 /* This is the partially failed retrans value for the transport 906 * and will be initialized from the assocs value. This can be changed 907 * using the SCTP_PEER_ADDR_THLDS socket option 908 */ 909 int pf_retrans; 910 /* PMTU : The current known path MTU. */ 911 __u32 pathmtu; 912 913 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 914 __u32 param_flags; 915 916 /* The number of times INIT has been sent on this transport. */ 917 int init_sent_count; 918 919 /* state : The current state of this destination, 920 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN. 921 */ 922 int state; 923 924 /* These are the error stats for this destination. */ 925 926 /* Error count : The current error count for this destination. */ 927 unsigned short error_count; 928 929 /* Per : A timer used by each destination. 930 * Destination : 931 * Timer : 932 * 933 * [Everywhere else in the text this is called T3-rtx. -ed] 934 */ 935 struct timer_list T3_rtx_timer; 936 937 /* Heartbeat timer is per destination. */ 938 struct timer_list hb_timer; 939 940 /* Timer to handle ICMP proto unreachable envets */ 941 struct timer_list proto_unreach_timer; 942 943 /* Timer to handler reconf chunk rtx */ 944 struct timer_list reconf_timer; 945 946 /* Since we're using per-destination retransmission timers 947 * (see above), we're also using per-destination "transmitted" 948 * queues. This probably ought to be a private struct 949 * accessible only within the outqueue, but it's not, yet. 950 */ 951 struct list_head transmitted; 952 953 /* We build bundle-able packets for this transport here. */ 954 struct sctp_packet packet; 955 956 /* This is the list of transports that have chunks to send. */ 957 struct list_head send_ready; 958 959 /* State information saved for SFR_CACC algorithm. The key 960 * idea in SFR_CACC is to maintain state at the sender on a 961 * per-destination basis when a changeover happens. 962 * char changeover_active; 963 * char cycling_changeover; 964 * __u32 next_tsn_at_change; 965 * char cacc_saw_newack; 966 */ 967 struct { 968 /* An unsigned integer, which stores the next TSN to be 969 * used by the sender, at the moment of changeover. 970 */ 971 __u32 next_tsn_at_change; 972 973 /* A flag which indicates the occurrence of a changeover */ 974 char changeover_active; 975 976 /* A flag which indicates whether the change of primary is 977 * the first switch to this destination address during an 978 * active switch. 979 */ 980 char cycling_changeover; 981 982 /* A temporary flag, which is used during the processing of 983 * a SACK to estimate the causative TSN(s)'s group. 984 */ 985 char cacc_saw_newack; 986 } cacc; 987 988 /* 64-bit random number sent with heartbeat. */ 989 __u64 hb_nonce; 990 991 struct rcu_head rcu; 992 }; 993 994 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *, 995 gfp_t); 996 void sctp_transport_set_owner(struct sctp_transport *, 997 struct sctp_association *); 998 void sctp_transport_route(struct sctp_transport *, union sctp_addr *, 999 struct sctp_sock *); 1000 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk); 1001 void sctp_transport_free(struct sctp_transport *); 1002 void sctp_transport_reset_t3_rtx(struct sctp_transport *); 1003 void sctp_transport_reset_hb_timer(struct sctp_transport *); 1004 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport); 1005 int sctp_transport_hold(struct sctp_transport *); 1006 void sctp_transport_put(struct sctp_transport *); 1007 void sctp_transport_update_rto(struct sctp_transport *, __u32); 1008 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32); 1009 void sctp_transport_lower_cwnd(struct sctp_transport *t, 1010 enum sctp_lower_cwnd reason); 1011 void sctp_transport_burst_limited(struct sctp_transport *); 1012 void sctp_transport_burst_reset(struct sctp_transport *); 1013 unsigned long sctp_transport_timeout(struct sctp_transport *); 1014 void sctp_transport_reset(struct sctp_transport *t); 1015 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu); 1016 void sctp_transport_immediate_rtx(struct sctp_transport *); 1017 void sctp_transport_dst_release(struct sctp_transport *t); 1018 void sctp_transport_dst_confirm(struct sctp_transport *t); 1019 1020 1021 /* This is the structure we use to queue packets as they come into 1022 * SCTP. We write packets to it and read chunks from it. 1023 */ 1024 struct sctp_inq { 1025 /* This is actually a queue of sctp_chunk each 1026 * containing a partially decoded packet. 1027 */ 1028 struct list_head in_chunk_list; 1029 /* This is the packet which is currently off the in queue and is 1030 * being worked on through the inbound chunk processing. 1031 */ 1032 struct sctp_chunk *in_progress; 1033 1034 /* This is the delayed task to finish delivering inbound 1035 * messages. 1036 */ 1037 struct work_struct immediate; 1038 }; 1039 1040 void sctp_inq_init(struct sctp_inq *); 1041 void sctp_inq_free(struct sctp_inq *); 1042 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet); 1043 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *); 1044 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *); 1045 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t); 1046 1047 /* This is the structure we use to hold outbound chunks. You push 1048 * chunks in and they automatically pop out the other end as bundled 1049 * packets (it calls (*output_handler)()). 1050 * 1051 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1, 1052 * and 8.2 of the v13 draft. 1053 * 1054 * It handles retransmissions. The connection to the timeout portion 1055 * of the state machine is through sctp_..._timeout() and timeout_handler. 1056 * 1057 * If you feed it SACKs, it will eat them. 1058 * 1059 * If you give it big chunks, it will fragment them. 1060 * 1061 * It assigns TSN's to data chunks. This happens at the last possible 1062 * instant before transmission. 1063 * 1064 * When free()'d, it empties itself out via output_handler(). 1065 */ 1066 struct sctp_outq { 1067 struct sctp_association *asoc; 1068 1069 /* Data pending that has never been transmitted. */ 1070 struct list_head out_chunk_list; 1071 1072 /* Stream scheduler being used */ 1073 struct sctp_sched_ops *sched; 1074 1075 unsigned int out_qlen; /* Total length of queued data chunks. */ 1076 1077 /* Error of send failed, may used in SCTP_SEND_FAILED event. */ 1078 unsigned int error; 1079 1080 /* These are control chunks we want to send. */ 1081 struct list_head control_chunk_list; 1082 1083 /* These are chunks that have been sacked but are above the 1084 * CTSN, or cumulative tsn ack point. 1085 */ 1086 struct list_head sacked; 1087 1088 /* Put chunks on this list to schedule them for 1089 * retransmission. 1090 */ 1091 struct list_head retransmit; 1092 1093 /* Put chunks on this list to save them for FWD TSN processing as 1094 * they were abandoned. 1095 */ 1096 struct list_head abandoned; 1097 1098 /* How many unackd bytes do we have in-flight? */ 1099 __u32 outstanding_bytes; 1100 1101 /* Are we doing fast-rtx on this queue */ 1102 char fast_rtx; 1103 1104 /* Corked? */ 1105 char cork; 1106 }; 1107 1108 void sctp_outq_init(struct sctp_association *, struct sctp_outq *); 1109 void sctp_outq_teardown(struct sctp_outq *); 1110 void sctp_outq_free(struct sctp_outq*); 1111 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t); 1112 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *); 1113 int sctp_outq_is_empty(const struct sctp_outq *); 1114 void sctp_outq_restart(struct sctp_outq *); 1115 1116 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport, 1117 enum sctp_retransmit_reason reason); 1118 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8); 1119 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp); 1120 void sctp_prsctp_prune(struct sctp_association *asoc, 1121 struct sctp_sndrcvinfo *sinfo, int msg_len); 1122 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn); 1123 /* Uncork and flush an outqueue. */ 1124 static inline void sctp_outq_cork(struct sctp_outq *q) 1125 { 1126 q->cork = 1; 1127 } 1128 1129 /* SCTP skb control block. 1130 * sctp_input_cb is currently used on rx and sock rx queue 1131 */ 1132 struct sctp_input_cb { 1133 union { 1134 struct inet_skb_parm h4; 1135 #if IS_ENABLED(CONFIG_IPV6) 1136 struct inet6_skb_parm h6; 1137 #endif 1138 } header; 1139 struct sctp_chunk *chunk; 1140 struct sctp_af *af; 1141 }; 1142 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0])) 1143 1144 struct sctp_output_cb { 1145 struct sk_buff *last; 1146 }; 1147 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0])) 1148 1149 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb) 1150 { 1151 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; 1152 1153 return chunk->head_skb ? : skb; 1154 } 1155 1156 /* These bind address data fields common between endpoints and associations */ 1157 struct sctp_bind_addr { 1158 1159 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1160 * 1161 * SCTP Port: The local SCTP port number the endpoint is 1162 * bound to. 1163 */ 1164 __u16 port; 1165 1166 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1167 * 1168 * Address List: The list of IP addresses that this instance 1169 * has bound. This information is passed to one's 1170 * peer(s) in INIT and INIT ACK chunks. 1171 */ 1172 struct list_head address_list; 1173 }; 1174 1175 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port); 1176 void sctp_bind_addr_free(struct sctp_bind_addr *); 1177 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest, 1178 const struct sctp_bind_addr *src, 1179 enum sctp_scope scope, gfp_t gfp, 1180 int flags); 1181 int sctp_bind_addr_dup(struct sctp_bind_addr *dest, 1182 const struct sctp_bind_addr *src, 1183 gfp_t gfp); 1184 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *, 1185 int new_size, __u8 addr_state, gfp_t gfp); 1186 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *); 1187 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *, 1188 struct sctp_sock *); 1189 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *, 1190 struct sctp_sock *, struct sctp_sock *); 1191 int sctp_bind_addr_state(const struct sctp_bind_addr *bp, 1192 const union sctp_addr *addr); 1193 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp, 1194 const union sctp_addr *addrs, 1195 int addrcnt, 1196 struct sctp_sock *opt); 1197 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp, 1198 int *addrs_len, 1199 gfp_t gfp); 1200 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len, 1201 __u16 port, gfp_t gfp); 1202 1203 enum sctp_scope sctp_scope(const union sctp_addr *addr); 1204 int sctp_in_scope(struct net *net, const union sctp_addr *addr, 1205 const enum sctp_scope scope); 1206 int sctp_is_any(struct sock *sk, const union sctp_addr *addr); 1207 int sctp_is_ep_boundall(struct sock *sk); 1208 1209 1210 /* What type of endpoint? */ 1211 enum sctp_endpoint_type { 1212 SCTP_EP_TYPE_SOCKET, 1213 SCTP_EP_TYPE_ASSOCIATION, 1214 }; 1215 1216 /* 1217 * A common base class to bridge the implmentation view of a 1218 * socket (usually listening) endpoint versus an association's 1219 * local endpoint. 1220 * This common structure is useful for several purposes: 1221 * 1) Common interface for lookup routines. 1222 * a) Subfunctions work for either endpoint or association 1223 * b) Single interface to lookup allows hiding the lookup lock rather 1224 * than acquiring it externally. 1225 * 2) Common interface for the inbound chunk handling/state machine. 1226 * 3) Common object handling routines for reference counting, etc. 1227 * 4) Disentangle association lookup from endpoint lookup, where we 1228 * do not have to find our endpoint to find our association. 1229 * 1230 */ 1231 1232 struct sctp_ep_common { 1233 /* Fields to help us manage our entries in the hash tables. */ 1234 struct hlist_node node; 1235 int hashent; 1236 1237 /* Runtime type information. What kind of endpoint is this? */ 1238 enum sctp_endpoint_type type; 1239 1240 /* Some fields to help us manage this object. 1241 * refcnt - Reference count access to this object. 1242 * dead - Do not attempt to use this object. 1243 */ 1244 refcount_t refcnt; 1245 bool dead; 1246 1247 /* What socket does this endpoint belong to? */ 1248 struct sock *sk; 1249 1250 /* This is where we receive inbound chunks. */ 1251 struct sctp_inq inqueue; 1252 1253 /* This substructure includes the defining parameters of the 1254 * endpoint: 1255 * bind_addr.port is our shared port number. 1256 * bind_addr.address_list is our set of local IP addresses. 1257 */ 1258 struct sctp_bind_addr bind_addr; 1259 }; 1260 1261 1262 /* RFC Section 1.4 Key Terms 1263 * 1264 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a 1265 * multi-homed host, an SCTP endpoint is represented to its peers as a 1266 * combination of a set of eligible destination transport addresses to 1267 * which SCTP packets can be sent and a set of eligible source 1268 * transport addresses from which SCTP packets can be received. 1269 * All transport addresses used by an SCTP endpoint must use the 1270 * same port number, but can use multiple IP addresses. A transport 1271 * address used by an SCTP endpoint must not be used by another 1272 * SCTP endpoint. In other words, a transport address is unique 1273 * to an SCTP endpoint. 1274 * 1275 * From an implementation perspective, each socket has one of these. 1276 * A TCP-style socket will have exactly one association on one of 1277 * these. An UDP-style socket will have multiple associations hanging 1278 * off one of these. 1279 */ 1280 1281 struct sctp_endpoint { 1282 /* Common substructure for endpoint and association. */ 1283 struct sctp_ep_common base; 1284 1285 /* Associations: A list of current associations and mappings 1286 * to the data consumers for each association. This 1287 * may be in the form of a hash table or other 1288 * implementation dependent structure. The data 1289 * consumers may be process identification 1290 * information such as file descriptors, named pipe 1291 * pointer, or table pointers dependent on how SCTP 1292 * is implemented. 1293 */ 1294 /* This is really a list of struct sctp_association entries. */ 1295 struct list_head asocs; 1296 1297 /* Secret Key: A secret key used by this endpoint to compute 1298 * the MAC. This SHOULD be a cryptographic quality 1299 * random number with a sufficient length. 1300 * Discussion in [RFC1750] can be helpful in 1301 * selection of the key. 1302 */ 1303 __u8 secret_key[SCTP_SECRET_SIZE]; 1304 1305 /* digest: This is a digest of the sctp cookie. This field is 1306 * only used on the receive path when we try to validate 1307 * that the cookie has not been tampered with. We put 1308 * this here so we pre-allocate this once and can re-use 1309 * on every receive. 1310 */ 1311 __u8 *digest; 1312 1313 /* sendbuf acct. policy. */ 1314 __u32 sndbuf_policy; 1315 1316 /* rcvbuf acct. policy. */ 1317 __u32 rcvbuf_policy; 1318 1319 /* SCTP AUTH: array of the HMACs that will be allocated 1320 * we need this per association so that we don't serialize 1321 */ 1322 struct crypto_shash **auth_hmacs; 1323 1324 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */ 1325 struct sctp_hmac_algo_param *auth_hmacs_list; 1326 1327 /* SCTP-AUTH: chunks to authenticate encoded into parameter */ 1328 struct sctp_chunks_param *auth_chunk_list; 1329 1330 /* SCTP-AUTH: endpoint shared keys */ 1331 struct list_head endpoint_shared_keys; 1332 __u16 active_key_id; 1333 __u8 auth_enable:1, 1334 prsctp_enable:1, 1335 reconf_enable:1; 1336 1337 __u8 strreset_enable; 1338 1339 /* Security identifiers from incoming (INIT). These are set by 1340 * security_sctp_assoc_request(). These will only be used by 1341 * SCTP TCP type sockets and peeled off connections as they 1342 * cause a new socket to be generated. security_sctp_sk_clone() 1343 * will then plug these into the new socket. 1344 */ 1345 1346 u32 secid; 1347 u32 peer_secid; 1348 }; 1349 1350 /* Recover the outter endpoint structure. */ 1351 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base) 1352 { 1353 struct sctp_endpoint *ep; 1354 1355 ep = container_of(base, struct sctp_endpoint, base); 1356 return ep; 1357 } 1358 1359 /* These are function signatures for manipulating endpoints. */ 1360 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t); 1361 void sctp_endpoint_free(struct sctp_endpoint *); 1362 void sctp_endpoint_put(struct sctp_endpoint *); 1363 void sctp_endpoint_hold(struct sctp_endpoint *); 1364 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *); 1365 struct sctp_association *sctp_endpoint_lookup_assoc( 1366 const struct sctp_endpoint *ep, 1367 const union sctp_addr *paddr, 1368 struct sctp_transport **); 1369 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep, 1370 const union sctp_addr *paddr); 1371 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *, 1372 struct net *, const union sctp_addr *); 1373 bool sctp_has_association(struct net *net, const union sctp_addr *laddr, 1374 const union sctp_addr *paddr); 1375 1376 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep, 1377 const struct sctp_association *asoc, 1378 enum sctp_cid cid, struct sctp_init_chunk *peer_init, 1379 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk); 1380 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk, 1381 const union sctp_addr *peer, 1382 struct sctp_init_chunk *init, gfp_t gfp); 1383 __u32 sctp_generate_tag(const struct sctp_endpoint *); 1384 __u32 sctp_generate_tsn(const struct sctp_endpoint *); 1385 1386 struct sctp_inithdr_host { 1387 __u32 init_tag; 1388 __u32 a_rwnd; 1389 __u16 num_outbound_streams; 1390 __u16 num_inbound_streams; 1391 __u32 initial_tsn; 1392 }; 1393 1394 struct sctp_stream_priorities { 1395 /* List of priorities scheduled */ 1396 struct list_head prio_sched; 1397 /* List of streams scheduled */ 1398 struct list_head active; 1399 /* The next stream stream in line */ 1400 struct sctp_stream_out_ext *next; 1401 __u16 prio; 1402 }; 1403 1404 struct sctp_stream_out_ext { 1405 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 1406 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 1407 struct list_head outq; /* chunks enqueued by this stream */ 1408 union { 1409 struct { 1410 /* Scheduled streams list */ 1411 struct list_head prio_list; 1412 struct sctp_stream_priorities *prio_head; 1413 }; 1414 /* Fields used by RR scheduler */ 1415 struct { 1416 struct list_head rr_list; 1417 }; 1418 }; 1419 }; 1420 1421 struct sctp_stream_out { 1422 union { 1423 __u32 mid; 1424 __u16 ssn; 1425 }; 1426 __u32 mid_uo; 1427 struct sctp_stream_out_ext *ext; 1428 __u8 state; 1429 }; 1430 1431 struct sctp_stream_in { 1432 union { 1433 __u32 mid; 1434 __u16 ssn; 1435 }; 1436 __u32 mid_uo; 1437 __u32 fsn; 1438 __u32 fsn_uo; 1439 char pd_mode; 1440 char pd_mode_uo; 1441 }; 1442 1443 struct sctp_stream { 1444 struct flex_array *out; 1445 struct flex_array *in; 1446 __u16 outcnt; 1447 __u16 incnt; 1448 /* Current stream being sent, if any */ 1449 struct sctp_stream_out *out_curr; 1450 union { 1451 /* Fields used by priority scheduler */ 1452 struct { 1453 /* List of priorities scheduled */ 1454 struct list_head prio_list; 1455 }; 1456 /* Fields used by RR scheduler */ 1457 struct { 1458 /* List of streams scheduled */ 1459 struct list_head rr_list; 1460 /* The next stream stream in line */ 1461 struct sctp_stream_out_ext *rr_next; 1462 }; 1463 }; 1464 struct sctp_stream_interleave *si; 1465 }; 1466 1467 static inline struct sctp_stream_out *sctp_stream_out( 1468 const struct sctp_stream *stream, 1469 __u16 sid) 1470 { 1471 return flex_array_get(stream->out, sid); 1472 } 1473 1474 static inline struct sctp_stream_in *sctp_stream_in( 1475 const struct sctp_stream *stream, 1476 __u16 sid) 1477 { 1478 return flex_array_get(stream->in, sid); 1479 } 1480 1481 #define SCTP_SO(s, i) sctp_stream_out((s), (i)) 1482 #define SCTP_SI(s, i) sctp_stream_in((s), (i)) 1483 1484 #define SCTP_STREAM_CLOSED 0x00 1485 #define SCTP_STREAM_OPEN 0x01 1486 1487 static inline __u16 sctp_datachk_len(const struct sctp_stream *stream) 1488 { 1489 return stream->si->data_chunk_len; 1490 } 1491 1492 static inline __u16 sctp_datahdr_len(const struct sctp_stream *stream) 1493 { 1494 return stream->si->data_chunk_len - sizeof(struct sctp_chunkhdr); 1495 } 1496 1497 static inline __u16 sctp_ftsnchk_len(const struct sctp_stream *stream) 1498 { 1499 return stream->si->ftsn_chunk_len; 1500 } 1501 1502 static inline __u16 sctp_ftsnhdr_len(const struct sctp_stream *stream) 1503 { 1504 return stream->si->ftsn_chunk_len - sizeof(struct sctp_chunkhdr); 1505 } 1506 1507 /* SCTP_GET_ASSOC_STATS counters */ 1508 struct sctp_priv_assoc_stats { 1509 /* Maximum observed rto in the association during subsequent 1510 * observations. Value is set to 0 if no RTO measurement took place 1511 * The transport where the max_rto was observed is returned in 1512 * obs_rto_ipaddr 1513 */ 1514 struct sockaddr_storage obs_rto_ipaddr; 1515 __u64 max_obs_rto; 1516 /* Total In and Out SACKs received and sent */ 1517 __u64 isacks; 1518 __u64 osacks; 1519 /* Total In and Out packets received and sent */ 1520 __u64 opackets; 1521 __u64 ipackets; 1522 /* Total retransmitted chunks */ 1523 __u64 rtxchunks; 1524 /* TSN received > next expected */ 1525 __u64 outofseqtsns; 1526 /* Duplicate Chunks received */ 1527 __u64 idupchunks; 1528 /* Gap Ack Blocks received */ 1529 __u64 gapcnt; 1530 /* Unordered data chunks sent and received */ 1531 __u64 ouodchunks; 1532 __u64 iuodchunks; 1533 /* Ordered data chunks sent and received */ 1534 __u64 oodchunks; 1535 __u64 iodchunks; 1536 /* Control chunks sent and received */ 1537 __u64 octrlchunks; 1538 __u64 ictrlchunks; 1539 }; 1540 1541 /* RFC2960 1542 * 1543 * 12. Recommended Transmission Control Block (TCB) Parameters 1544 * 1545 * This section details a recommended set of parameters that should 1546 * be contained within the TCB for an implementation. This section is 1547 * for illustrative purposes and should not be deemed as requirements 1548 * on an implementation or as an exhaustive list of all parameters 1549 * inside an SCTP TCB. Each implementation may need its own additional 1550 * parameters for optimization. 1551 */ 1552 1553 1554 /* Here we have information about each individual association. */ 1555 struct sctp_association { 1556 1557 /* A base structure common to endpoint and association. 1558 * In this context, it represents the associations's view 1559 * of the local endpoint of the association. 1560 */ 1561 struct sctp_ep_common base; 1562 1563 /* Associations on the same socket. */ 1564 struct list_head asocs; 1565 1566 /* association id. */ 1567 sctp_assoc_t assoc_id; 1568 1569 /* This is our parent endpoint. */ 1570 struct sctp_endpoint *ep; 1571 1572 /* These are those association elements needed in the cookie. */ 1573 struct sctp_cookie c; 1574 1575 /* This is all information about our peer. */ 1576 struct { 1577 /* transport_addr_list 1578 * 1579 * Peer : A list of SCTP transport addresses that the 1580 * Transport : peer is bound to. This information is derived 1581 * Address : from the INIT or INIT ACK and is used to 1582 * List : associate an inbound packet with a given 1583 * : association. Normally this information is 1584 * : hashed or keyed for quick lookup and access 1585 * : of the TCB. 1586 * : The list is also initialized with the list 1587 * : of addresses passed with the sctp_connectx() 1588 * : call. 1589 * 1590 * It is a list of SCTP_transport's. 1591 */ 1592 struct list_head transport_addr_list; 1593 1594 /* rwnd 1595 * 1596 * Peer Rwnd : Current calculated value of the peer's rwnd. 1597 */ 1598 __u32 rwnd; 1599 1600 /* transport_count 1601 * 1602 * Peer : A count of the number of peer addresses 1603 * Transport : in the Peer Transport Address List. 1604 * Address : 1605 * Count : 1606 */ 1607 __u16 transport_count; 1608 1609 /* port 1610 * The transport layer port number. 1611 */ 1612 __u16 port; 1613 1614 /* primary_path 1615 * 1616 * Primary : This is the current primary destination 1617 * Path : transport address of the peer endpoint. It 1618 * : may also specify a source transport address 1619 * : on this endpoint. 1620 * 1621 * All of these paths live on transport_addr_list. 1622 * 1623 * At the bakeoffs, we discovered that the intent of 1624 * primaryPath is that it only changes when the ULP 1625 * asks to have it changed. We add the activePath to 1626 * designate the connection we are currently using to 1627 * transmit new data and most control chunks. 1628 */ 1629 struct sctp_transport *primary_path; 1630 1631 /* Cache the primary path address here, when we 1632 * need a an address for msg_name. 1633 */ 1634 union sctp_addr primary_addr; 1635 1636 /* active_path 1637 * The path that we are currently using to 1638 * transmit new data and most control chunks. 1639 */ 1640 struct sctp_transport *active_path; 1641 1642 /* retran_path 1643 * 1644 * RFC2960 6.4 Multi-homed SCTP Endpoints 1645 * ... 1646 * Furthermore, when its peer is multi-homed, an 1647 * endpoint SHOULD try to retransmit a chunk to an 1648 * active destination transport address that is 1649 * different from the last destination address to 1650 * which the DATA chunk was sent. 1651 */ 1652 struct sctp_transport *retran_path; 1653 1654 /* Pointer to last transport I have sent on. */ 1655 struct sctp_transport *last_sent_to; 1656 1657 /* This is the last transport I have received DATA on. */ 1658 struct sctp_transport *last_data_from; 1659 1660 /* 1661 * Mapping An array of bits or bytes indicating which out of 1662 * Array order TSN's have been received (relative to the 1663 * Last Rcvd TSN). If no gaps exist, i.e. no out of 1664 * order packets have been received, this array 1665 * will be set to all zero. This structure may be 1666 * in the form of a circular buffer or bit array. 1667 * 1668 * Last Rcvd : This is the last TSN received in 1669 * TSN : sequence. This value is set initially by 1670 * : taking the peer's Initial TSN, received in 1671 * : the INIT or INIT ACK chunk, and subtracting 1672 * : one from it. 1673 * 1674 * Throughout most of the specification this is called the 1675 * "Cumulative TSN ACK Point". In this case, we 1676 * ignore the advice in 12.2 in favour of the term 1677 * used in the bulk of the text. This value is hidden 1678 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn(). 1679 */ 1680 struct sctp_tsnmap tsn_map; 1681 1682 /* This mask is used to disable sending the ASCONF chunk 1683 * with specified parameter to peer. 1684 */ 1685 __be16 addip_disabled_mask; 1686 1687 /* These are capabilities which our peer advertised. */ 1688 __u8 ecn_capable:1, /* Can peer do ECN? */ 1689 ipv4_address:1, /* Peer understands IPv4 addresses? */ 1690 ipv6_address:1, /* Peer understands IPv6 addresses? */ 1691 hostname_address:1, /* Peer understands DNS addresses? */ 1692 asconf_capable:1, /* Does peer support ADDIP? */ 1693 prsctp_capable:1, /* Can peer do PR-SCTP? */ 1694 reconf_capable:1, /* Can peer do RE-CONFIG? */ 1695 auth_capable:1; /* Is peer doing SCTP-AUTH? */ 1696 1697 /* sack_needed : This flag indicates if the next received 1698 * : packet is to be responded to with a 1699 * : SACK. This is initialized to 0. When a packet 1700 * : is received sack_cnt is incremented. If this value 1701 * : reaches 2 or more, a SACK is sent and the 1702 * : value is reset to 0. Note: This is used only 1703 * : when no DATA chunks are received out of 1704 * : order. When DATA chunks are out of order, 1705 * : SACK's are not delayed (see Section 6). 1706 */ 1707 __u8 sack_needed:1, /* Do we need to sack the peer? */ 1708 sack_generation:1, 1709 zero_window_announced:1; 1710 __u32 sack_cnt; 1711 1712 __u32 adaptation_ind; /* Adaptation Code point. */ 1713 1714 struct sctp_inithdr_host i; 1715 void *cookie; 1716 int cookie_len; 1717 1718 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. 1719 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the 1720 * Initial TSN Value minus 1 1721 */ 1722 __u32 addip_serial; 1723 1724 /* SCTP-AUTH: We need to know pears random number, hmac list 1725 * and authenticated chunk list. All that is part of the 1726 * cookie and these are just pointers to those locations 1727 */ 1728 struct sctp_random_param *peer_random; 1729 struct sctp_chunks_param *peer_chunks; 1730 struct sctp_hmac_algo_param *peer_hmacs; 1731 } peer; 1732 1733 /* State : A state variable indicating what state the 1734 * : association is in, i.e. COOKIE-WAIT, 1735 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING, 1736 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT. 1737 * 1738 * Note: No "CLOSED" state is illustrated since if a 1739 * association is "CLOSED" its TCB SHOULD be removed. 1740 * 1741 * In this implementation we DO have a CLOSED 1742 * state which is used during initiation and shutdown. 1743 * 1744 * State takes values from SCTP_STATE_*. 1745 */ 1746 enum sctp_state state; 1747 1748 /* Overall : The overall association error count. 1749 * Error Count : [Clear this any time I get something.] 1750 */ 1751 int overall_error_count; 1752 1753 /* The cookie life I award for any cookie. */ 1754 ktime_t cookie_life; 1755 1756 /* These are the association's initial, max, and min RTO values. 1757 * These values will be initialized by system defaults, but can 1758 * be modified via the SCTP_RTOINFO socket option. 1759 */ 1760 unsigned long rto_initial; 1761 unsigned long rto_max; 1762 unsigned long rto_min; 1763 1764 /* Maximum number of new data packets that can be sent in a burst. */ 1765 int max_burst; 1766 1767 /* This is the max_retrans value for the association. This value will 1768 * be initialized initialized from system defaults, but can be 1769 * modified by the SCTP_ASSOCINFO socket option. 1770 */ 1771 int max_retrans; 1772 1773 /* This is the partially failed retrans value for the transport 1774 * and will be initialized from the assocs value. This can be 1775 * changed using the SCTP_PEER_ADDR_THLDS socket option 1776 */ 1777 int pf_retrans; 1778 1779 /* Maximum number of times the endpoint will retransmit INIT */ 1780 __u16 max_init_attempts; 1781 1782 /* How many times have we resent an INIT? */ 1783 __u16 init_retries; 1784 1785 /* The largest timeout or RTO value to use in attempting an INIT */ 1786 unsigned long max_init_timeo; 1787 1788 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 1789 * the destination address every heartbeat interval. This value 1790 * will be inherited by all new transports. 1791 */ 1792 unsigned long hbinterval; 1793 1794 /* This is the max_retrans value for new transports in the 1795 * association. 1796 */ 1797 __u16 pathmaxrxt; 1798 1799 __u32 flowlabel; 1800 __u8 dscp; 1801 1802 /* Flag that path mtu update is pending */ 1803 __u8 pmtu_pending; 1804 1805 /* Association : The smallest PMTU discovered for all of the 1806 * PMTU : peer's transport addresses. 1807 */ 1808 __u32 pathmtu; 1809 1810 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 1811 __u32 param_flags; 1812 1813 __u32 sackfreq; 1814 /* SACK delay timeout */ 1815 unsigned long sackdelay; 1816 1817 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES]; 1818 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES]; 1819 1820 /* Transport to which SHUTDOWN chunk was last sent. */ 1821 struct sctp_transport *shutdown_last_sent_to; 1822 1823 /* Transport to which INIT chunk was last sent. */ 1824 struct sctp_transport *init_last_sent_to; 1825 1826 /* How many times have we resent a SHUTDOWN */ 1827 int shutdown_retries; 1828 1829 /* Next TSN : The next TSN number to be assigned to a new 1830 * : DATA chunk. This is sent in the INIT or INIT 1831 * : ACK chunk to the peer and incremented each 1832 * : time a DATA chunk is assigned a TSN 1833 * : (normally just prior to transmit or during 1834 * : fragmentation). 1835 */ 1836 __u32 next_tsn; 1837 1838 /* 1839 * Last Rcvd : This is the last TSN received in sequence. This value 1840 * TSN : is set initially by taking the peer's Initial TSN, 1841 * : received in the INIT or INIT ACK chunk, and 1842 * : subtracting one from it. 1843 * 1844 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point. 1845 */ 1846 1847 __u32 ctsn_ack_point; 1848 1849 /* PR-SCTP Advanced.Peer.Ack.Point */ 1850 __u32 adv_peer_ack_point; 1851 1852 /* Highest TSN that is acknowledged by incoming SACKs. */ 1853 __u32 highest_sacked; 1854 1855 /* TSN marking the fast recovery exit point */ 1856 __u32 fast_recovery_exit; 1857 1858 /* Flag to track the current fast recovery state */ 1859 __u8 fast_recovery; 1860 1861 /* The number of unacknowledged data chunks. Reported through 1862 * the SCTP_STATUS sockopt. 1863 */ 1864 __u16 unack_data; 1865 1866 /* The total number of data chunks that we've had to retransmit 1867 * as the result of a T3 timer expiration 1868 */ 1869 __u32 rtx_data_chunks; 1870 1871 /* This is the association's receive buffer space. This value is used 1872 * to set a_rwnd field in an INIT or a SACK chunk. 1873 */ 1874 __u32 rwnd; 1875 1876 /* This is the last advertised value of rwnd over a SACK chunk. */ 1877 __u32 a_rwnd; 1878 1879 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed 1880 * to slop over a maximum of the association's frag_point. 1881 */ 1882 __u32 rwnd_over; 1883 1884 /* Keeps treack of rwnd pressure. This happens when we have 1885 * a window, but not recevie buffer (i.e small packets). This one 1886 * is releases slowly (1 PMTU at a time ). 1887 */ 1888 __u32 rwnd_press; 1889 1890 /* This is the sndbuf size in use for the association. 1891 * This corresponds to the sndbuf size for the association, 1892 * as specified in the sk->sndbuf. 1893 */ 1894 int sndbuf_used; 1895 1896 /* This is the amount of memory that this association has allocated 1897 * in the receive path at any given time. 1898 */ 1899 atomic_t rmem_alloc; 1900 1901 /* This is the wait queue head for send requests waiting on 1902 * the association sndbuf space. 1903 */ 1904 wait_queue_head_t wait; 1905 1906 /* The message size at which SCTP fragmentation will occur. */ 1907 __u32 frag_point; 1908 __u32 user_frag; 1909 1910 /* Counter used to count INIT errors. */ 1911 int init_err_counter; 1912 1913 /* Count the number of INIT cycles (for doubling timeout). */ 1914 int init_cycle; 1915 1916 /* Default send parameters. */ 1917 __u16 default_stream; 1918 __u16 default_flags; 1919 __u32 default_ppid; 1920 __u32 default_context; 1921 __u32 default_timetolive; 1922 1923 /* Default receive parameters */ 1924 __u32 default_rcv_context; 1925 1926 /* Stream arrays */ 1927 struct sctp_stream stream; 1928 1929 /* All outbound chunks go through this structure. */ 1930 struct sctp_outq outqueue; 1931 1932 /* A smart pipe that will handle reordering and fragmentation, 1933 * as well as handle passing events up to the ULP. 1934 */ 1935 struct sctp_ulpq ulpq; 1936 1937 /* Last TSN that caused an ECNE Chunk to be sent. */ 1938 __u32 last_ecne_tsn; 1939 1940 /* Last TSN that caused a CWR Chunk to be sent. */ 1941 __u32 last_cwr_tsn; 1942 1943 /* How many duplicated TSNs have we seen? */ 1944 int numduptsns; 1945 1946 /* These are to support 1947 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses 1948 * and Enforcement of Flow and Message Limits" 1949 * <draft-ietf-tsvwg-addip-sctp-02.txt> 1950 * or "ADDIP" for short. 1951 */ 1952 1953 1954 1955 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1956 * 1957 * R1) One and only one ASCONF Chunk MAY be in transit and 1958 * unacknowledged at any one time. If a sender, after sending 1959 * an ASCONF chunk, decides it needs to transfer another 1960 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1961 * returns from the previous ASCONF Chunk before sending a 1962 * subsequent ASCONF. Note this restriction binds each side, 1963 * so at any time two ASCONF may be in-transit on any given 1964 * association (one sent from each endpoint). 1965 * 1966 * [This is our one-and-only-one ASCONF in flight. If we do 1967 * not have an ASCONF in flight, this is NULL.] 1968 */ 1969 struct sctp_chunk *addip_last_asconf; 1970 1971 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk. 1972 * 1973 * This is needed to implement itmes E1 - E4 of the updated 1974 * spec. Here is the justification: 1975 * 1976 * Since the peer may bundle multiple ASCONF chunks toward us, 1977 * we now need the ability to cache multiple ACKs. The section 1978 * describes in detail how they are cached and cleaned up. 1979 */ 1980 struct list_head asconf_ack_list; 1981 1982 /* These ASCONF chunks are waiting to be sent. 1983 * 1984 * These chunaks can't be pushed to outqueue until receiving 1985 * ASCONF_ACK for the previous ASCONF indicated by 1986 * addip_last_asconf, so as to guarantee that only one ASCONF 1987 * is in flight at any time. 1988 * 1989 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1990 * 1991 * In defining the ASCONF Chunk transfer procedures, it is 1992 * essential that these transfers MUST NOT cause congestion 1993 * within the network. To achieve this, we place these 1994 * restrictions on the transfer of ASCONF Chunks: 1995 * 1996 * R1) One and only one ASCONF Chunk MAY be in transit and 1997 * unacknowledged at any one time. If a sender, after sending 1998 * an ASCONF chunk, decides it needs to transfer another 1999 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 2000 * returns from the previous ASCONF Chunk before sending a 2001 * subsequent ASCONF. Note this restriction binds each side, 2002 * so at any time two ASCONF may be in-transit on any given 2003 * association (one sent from each endpoint). 2004 * 2005 * 2006 * [I really think this is EXACTLY the sort of intelligence 2007 * which already resides in sctp_outq. Please move this 2008 * queue and its supporting logic down there. --piggy] 2009 */ 2010 struct list_head addip_chunk_list; 2011 2012 /* ADDIP Section 4.1 ASCONF Chunk Procedures 2013 * 2014 * A2) A serial number should be assigned to the Chunk. The 2015 * serial number SHOULD be a monotonically increasing 2016 * number. The serial number SHOULD be initialized at 2017 * the start of the association to the same value as the 2018 * Initial TSN and every time a new ASCONF chunk is created 2019 * it is incremented by one after assigning the serial number 2020 * to the newly created chunk. 2021 * 2022 * ADDIP 2023 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF) 2024 * 2025 * Serial Number : 32 bits (unsigned integer) 2026 * 2027 * This value represents a Serial Number for the ASCONF 2028 * Chunk. The valid range of Serial Number is from 0 to 2029 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0 2030 * after reaching 4294967295. 2031 */ 2032 __u32 addip_serial; 2033 int src_out_of_asoc_ok; 2034 union sctp_addr *asconf_addr_del_pending; 2035 struct sctp_transport *new_transport; 2036 2037 /* SCTP AUTH: list of the endpoint shared keys. These 2038 * keys are provided out of band by the user applicaton 2039 * and can't change during the lifetime of the association 2040 */ 2041 struct list_head endpoint_shared_keys; 2042 2043 /* SCTP AUTH: 2044 * The current generated assocaition shared key (secret) 2045 */ 2046 struct sctp_auth_bytes *asoc_shared_key; 2047 struct sctp_shared_key *shkey; 2048 2049 /* SCTP AUTH: hmac id of the first peer requested algorithm 2050 * that we support. 2051 */ 2052 __u16 default_hmac_id; 2053 2054 __u16 active_key_id; 2055 2056 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */ 2057 temp:1, /* Is it a temporary association? */ 2058 force_delay:1, 2059 intl_enable:1, 2060 prsctp_enable:1, 2061 reconf_enable:1; 2062 2063 __u8 strreset_enable; 2064 __u8 strreset_outstanding; /* request param count on the fly */ 2065 2066 __u32 strreset_outseq; /* Update after receiving response */ 2067 __u32 strreset_inseq; /* Update after receiving request */ 2068 __u32 strreset_result[2]; /* save the results of last 2 responses */ 2069 2070 struct sctp_chunk *strreset_chunk; /* save request chunk */ 2071 2072 struct sctp_priv_assoc_stats stats; 2073 2074 int sent_cnt_removable; 2075 2076 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 2077 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 2078 }; 2079 2080 2081 /* An eyecatcher for determining if we are really looking at an 2082 * association data structure. 2083 */ 2084 enum { 2085 SCTP_ASSOC_EYECATCHER = 0xa550c123, 2086 }; 2087 2088 /* Recover the outter association structure. */ 2089 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base) 2090 { 2091 struct sctp_association *asoc; 2092 2093 asoc = container_of(base, struct sctp_association, base); 2094 return asoc; 2095 } 2096 2097 /* These are function signatures for manipulating associations. */ 2098 2099 2100 struct sctp_association * 2101 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk, 2102 enum sctp_scope scope, gfp_t gfp); 2103 void sctp_association_free(struct sctp_association *); 2104 void sctp_association_put(struct sctp_association *); 2105 void sctp_association_hold(struct sctp_association *); 2106 2107 struct sctp_transport *sctp_assoc_choose_alter_transport( 2108 struct sctp_association *, struct sctp_transport *); 2109 void sctp_assoc_update_retran_path(struct sctp_association *); 2110 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *, 2111 const union sctp_addr *); 2112 int sctp_assoc_lookup_laddr(struct sctp_association *asoc, 2113 const union sctp_addr *laddr); 2114 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *, 2115 const union sctp_addr *address, 2116 const gfp_t gfp, 2117 const int peer_state); 2118 void sctp_assoc_del_peer(struct sctp_association *asoc, 2119 const union sctp_addr *addr); 2120 void sctp_assoc_rm_peer(struct sctp_association *asoc, 2121 struct sctp_transport *peer); 2122 void sctp_assoc_control_transport(struct sctp_association *asoc, 2123 struct sctp_transport *transport, 2124 enum sctp_transport_cmd command, 2125 sctp_sn_error_t error); 2126 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32); 2127 void sctp_assoc_migrate(struct sctp_association *, struct sock *); 2128 int sctp_assoc_update(struct sctp_association *old, 2129 struct sctp_association *new); 2130 2131 __u32 sctp_association_get_next_tsn(struct sctp_association *); 2132 2133 void sctp_assoc_update_frag_point(struct sctp_association *asoc); 2134 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu); 2135 void sctp_assoc_sync_pmtu(struct sctp_association *asoc); 2136 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int); 2137 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int); 2138 void sctp_assoc_set_primary(struct sctp_association *, 2139 struct sctp_transport *); 2140 void sctp_assoc_del_nonprimary_peers(struct sctp_association *, 2141 struct sctp_transport *); 2142 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, 2143 enum sctp_scope scope, gfp_t gfp); 2144 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *, 2145 struct sctp_cookie*, 2146 gfp_t gfp); 2147 int sctp_assoc_set_id(struct sctp_association *, gfp_t); 2148 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc); 2149 struct sctp_chunk *sctp_assoc_lookup_asconf_ack( 2150 const struct sctp_association *asoc, 2151 __be32 serial); 2152 void sctp_asconf_queue_teardown(struct sctp_association *asoc); 2153 2154 int sctp_cmp_addr_exact(const union sctp_addr *ss1, 2155 const union sctp_addr *ss2); 2156 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc); 2157 2158 /* A convenience structure to parse out SCTP specific CMSGs. */ 2159 struct sctp_cmsgs { 2160 struct sctp_initmsg *init; 2161 struct sctp_sndrcvinfo *srinfo; 2162 struct sctp_sndinfo *sinfo; 2163 struct sctp_prinfo *prinfo; 2164 struct sctp_authinfo *authinfo; 2165 struct msghdr *addrs_msg; 2166 }; 2167 2168 /* Structure for tracking memory objects */ 2169 struct sctp_dbg_objcnt_entry { 2170 char *label; 2171 atomic_t *counter; 2172 }; 2173 2174 #endif /* __sctp_structs_h__ */ 2175