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 /* When was the last time that we heard from this transport? We use 880 * this to pick new active and retran paths. 881 */ 882 ktime_t last_time_heard; 883 884 /* When was the last time that we sent a chunk using this 885 * transport? We use this to check for idle transports 886 */ 887 unsigned long last_time_sent; 888 889 /* Last time(in jiffies) when cwnd is reduced due to the congestion 890 * indication based on ECNE chunk. 891 */ 892 unsigned long last_time_ecne_reduced; 893 894 /* This is the max_retrans value for the transport and will 895 * be initialized from the assocs value. This can be changed 896 * using the SCTP_SET_PEER_ADDR_PARAMS socket option. 897 */ 898 __u16 pathmaxrxt; 899 900 __u32 flowlabel; 901 __u8 dscp; 902 903 /* This is the partially failed retrans value for the transport 904 * and will be initialized from the assocs value. This can be changed 905 * using the SCTP_PEER_ADDR_THLDS socket option 906 */ 907 int pf_retrans; 908 /* PMTU : The current known path MTU. */ 909 __u32 pathmtu; 910 911 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 912 __u32 param_flags; 913 914 /* The number of times INIT has been sent on this transport. */ 915 int init_sent_count; 916 917 /* state : The current state of this destination, 918 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN. 919 */ 920 int state; 921 922 /* These are the error stats for this destination. */ 923 924 /* Error count : The current error count for this destination. */ 925 unsigned short error_count; 926 927 /* Per : A timer used by each destination. 928 * Destination : 929 * Timer : 930 * 931 * [Everywhere else in the text this is called T3-rtx. -ed] 932 */ 933 struct timer_list T3_rtx_timer; 934 935 /* Heartbeat timer is per destination. */ 936 struct timer_list hb_timer; 937 938 /* Timer to handle ICMP proto unreachable envets */ 939 struct timer_list proto_unreach_timer; 940 941 /* Timer to handler reconf chunk rtx */ 942 struct timer_list reconf_timer; 943 944 /* Since we're using per-destination retransmission timers 945 * (see above), we're also using per-destination "transmitted" 946 * queues. This probably ought to be a private struct 947 * accessible only within the outqueue, but it's not, yet. 948 */ 949 struct list_head transmitted; 950 951 /* We build bundle-able packets for this transport here. */ 952 struct sctp_packet packet; 953 954 /* This is the list of transports that have chunks to send. */ 955 struct list_head send_ready; 956 957 /* State information saved for SFR_CACC algorithm. The key 958 * idea in SFR_CACC is to maintain state at the sender on a 959 * per-destination basis when a changeover happens. 960 * char changeover_active; 961 * char cycling_changeover; 962 * __u32 next_tsn_at_change; 963 * char cacc_saw_newack; 964 */ 965 struct { 966 /* An unsigned integer, which stores the next TSN to be 967 * used by the sender, at the moment of changeover. 968 */ 969 __u32 next_tsn_at_change; 970 971 /* A flag which indicates the occurrence of a changeover */ 972 char changeover_active; 973 974 /* A flag which indicates whether the change of primary is 975 * the first switch to this destination address during an 976 * active switch. 977 */ 978 char cycling_changeover; 979 980 /* A temporary flag, which is used during the processing of 981 * a SACK to estimate the causative TSN(s)'s group. 982 */ 983 char cacc_saw_newack; 984 } cacc; 985 986 /* 64-bit random number sent with heartbeat. */ 987 __u64 hb_nonce; 988 989 struct rcu_head rcu; 990 }; 991 992 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *, 993 gfp_t); 994 void sctp_transport_set_owner(struct sctp_transport *, 995 struct sctp_association *); 996 void sctp_transport_route(struct sctp_transport *, union sctp_addr *, 997 struct sctp_sock *); 998 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk); 999 void sctp_transport_free(struct sctp_transport *); 1000 void sctp_transport_reset_t3_rtx(struct sctp_transport *); 1001 void sctp_transport_reset_hb_timer(struct sctp_transport *); 1002 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport); 1003 int sctp_transport_hold(struct sctp_transport *); 1004 void sctp_transport_put(struct sctp_transport *); 1005 void sctp_transport_update_rto(struct sctp_transport *, __u32); 1006 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32); 1007 void sctp_transport_lower_cwnd(struct sctp_transport *t, 1008 enum sctp_lower_cwnd reason); 1009 void sctp_transport_burst_limited(struct sctp_transport *); 1010 void sctp_transport_burst_reset(struct sctp_transport *); 1011 unsigned long sctp_transport_timeout(struct sctp_transport *); 1012 void sctp_transport_reset(struct sctp_transport *t); 1013 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu); 1014 void sctp_transport_immediate_rtx(struct sctp_transport *); 1015 void sctp_transport_dst_release(struct sctp_transport *t); 1016 void sctp_transport_dst_confirm(struct sctp_transport *t); 1017 1018 1019 /* This is the structure we use to queue packets as they come into 1020 * SCTP. We write packets to it and read chunks from it. 1021 */ 1022 struct sctp_inq { 1023 /* This is actually a queue of sctp_chunk each 1024 * containing a partially decoded packet. 1025 */ 1026 struct list_head in_chunk_list; 1027 /* This is the packet which is currently off the in queue and is 1028 * being worked on through the inbound chunk processing. 1029 */ 1030 struct sctp_chunk *in_progress; 1031 1032 /* This is the delayed task to finish delivering inbound 1033 * messages. 1034 */ 1035 struct work_struct immediate; 1036 }; 1037 1038 void sctp_inq_init(struct sctp_inq *); 1039 void sctp_inq_free(struct sctp_inq *); 1040 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet); 1041 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *); 1042 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *); 1043 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t); 1044 1045 /* This is the structure we use to hold outbound chunks. You push 1046 * chunks in and they automatically pop out the other end as bundled 1047 * packets (it calls (*output_handler)()). 1048 * 1049 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1, 1050 * and 8.2 of the v13 draft. 1051 * 1052 * It handles retransmissions. The connection to the timeout portion 1053 * of the state machine is through sctp_..._timeout() and timeout_handler. 1054 * 1055 * If you feed it SACKs, it will eat them. 1056 * 1057 * If you give it big chunks, it will fragment them. 1058 * 1059 * It assigns TSN's to data chunks. This happens at the last possible 1060 * instant before transmission. 1061 * 1062 * When free()'d, it empties itself out via output_handler(). 1063 */ 1064 struct sctp_outq { 1065 struct sctp_association *asoc; 1066 1067 /* Data pending that has never been transmitted. */ 1068 struct list_head out_chunk_list; 1069 1070 /* Stream scheduler being used */ 1071 struct sctp_sched_ops *sched; 1072 1073 unsigned int out_qlen; /* Total length of queued data chunks. */ 1074 1075 /* Error of send failed, may used in SCTP_SEND_FAILED event. */ 1076 unsigned int error; 1077 1078 /* These are control chunks we want to send. */ 1079 struct list_head control_chunk_list; 1080 1081 /* These are chunks that have been sacked but are above the 1082 * CTSN, or cumulative tsn ack point. 1083 */ 1084 struct list_head sacked; 1085 1086 /* Put chunks on this list to schedule them for 1087 * retransmission. 1088 */ 1089 struct list_head retransmit; 1090 1091 /* Put chunks on this list to save them for FWD TSN processing as 1092 * they were abandoned. 1093 */ 1094 struct list_head abandoned; 1095 1096 /* How many unackd bytes do we have in-flight? */ 1097 __u32 outstanding_bytes; 1098 1099 /* Are we doing fast-rtx on this queue */ 1100 char fast_rtx; 1101 1102 /* Corked? */ 1103 char cork; 1104 }; 1105 1106 void sctp_outq_init(struct sctp_association *, struct sctp_outq *); 1107 void sctp_outq_teardown(struct sctp_outq *); 1108 void sctp_outq_free(struct sctp_outq*); 1109 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t); 1110 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *); 1111 int sctp_outq_is_empty(const struct sctp_outq *); 1112 void sctp_outq_restart(struct sctp_outq *); 1113 1114 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport, 1115 enum sctp_retransmit_reason reason); 1116 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8); 1117 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp); 1118 void sctp_prsctp_prune(struct sctp_association *asoc, 1119 struct sctp_sndrcvinfo *sinfo, int msg_len); 1120 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn); 1121 /* Uncork and flush an outqueue. */ 1122 static inline void sctp_outq_cork(struct sctp_outq *q) 1123 { 1124 q->cork = 1; 1125 } 1126 1127 /* SCTP skb control block. 1128 * sctp_input_cb is currently used on rx and sock rx queue 1129 */ 1130 struct sctp_input_cb { 1131 union { 1132 struct inet_skb_parm h4; 1133 #if IS_ENABLED(CONFIG_IPV6) 1134 struct inet6_skb_parm h6; 1135 #endif 1136 } header; 1137 struct sctp_chunk *chunk; 1138 struct sctp_af *af; 1139 }; 1140 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0])) 1141 1142 struct sctp_output_cb { 1143 struct sk_buff *last; 1144 }; 1145 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0])) 1146 1147 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb) 1148 { 1149 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; 1150 1151 return chunk->head_skb ? : skb; 1152 } 1153 1154 /* These bind address data fields common between endpoints and associations */ 1155 struct sctp_bind_addr { 1156 1157 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1158 * 1159 * SCTP Port: The local SCTP port number the endpoint is 1160 * bound to. 1161 */ 1162 __u16 port; 1163 1164 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1165 * 1166 * Address List: The list of IP addresses that this instance 1167 * has bound. This information is passed to one's 1168 * peer(s) in INIT and INIT ACK chunks. 1169 */ 1170 struct list_head address_list; 1171 }; 1172 1173 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port); 1174 void sctp_bind_addr_free(struct sctp_bind_addr *); 1175 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest, 1176 const struct sctp_bind_addr *src, 1177 enum sctp_scope scope, gfp_t gfp, 1178 int flags); 1179 int sctp_bind_addr_dup(struct sctp_bind_addr *dest, 1180 const struct sctp_bind_addr *src, 1181 gfp_t gfp); 1182 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *, 1183 int new_size, __u8 addr_state, gfp_t gfp); 1184 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *); 1185 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *, 1186 struct sctp_sock *); 1187 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *, 1188 struct sctp_sock *, struct sctp_sock *); 1189 int sctp_bind_addr_state(const struct sctp_bind_addr *bp, 1190 const union sctp_addr *addr); 1191 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp, 1192 const union sctp_addr *addrs, 1193 int addrcnt, 1194 struct sctp_sock *opt); 1195 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp, 1196 int *addrs_len, 1197 gfp_t gfp); 1198 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len, 1199 __u16 port, gfp_t gfp); 1200 1201 enum sctp_scope sctp_scope(const union sctp_addr *addr); 1202 int sctp_in_scope(struct net *net, const union sctp_addr *addr, 1203 const enum sctp_scope scope); 1204 int sctp_is_any(struct sock *sk, const union sctp_addr *addr); 1205 int sctp_is_ep_boundall(struct sock *sk); 1206 1207 1208 /* What type of endpoint? */ 1209 enum sctp_endpoint_type { 1210 SCTP_EP_TYPE_SOCKET, 1211 SCTP_EP_TYPE_ASSOCIATION, 1212 }; 1213 1214 /* 1215 * A common base class to bridge the implmentation view of a 1216 * socket (usually listening) endpoint versus an association's 1217 * local endpoint. 1218 * This common structure is useful for several purposes: 1219 * 1) Common interface for lookup routines. 1220 * a) Subfunctions work for either endpoint or association 1221 * b) Single interface to lookup allows hiding the lookup lock rather 1222 * than acquiring it externally. 1223 * 2) Common interface for the inbound chunk handling/state machine. 1224 * 3) Common object handling routines for reference counting, etc. 1225 * 4) Disentangle association lookup from endpoint lookup, where we 1226 * do not have to find our endpoint to find our association. 1227 * 1228 */ 1229 1230 struct sctp_ep_common { 1231 /* Fields to help us manage our entries in the hash tables. */ 1232 struct hlist_node node; 1233 int hashent; 1234 1235 /* Runtime type information. What kind of endpoint is this? */ 1236 enum sctp_endpoint_type type; 1237 1238 /* Some fields to help us manage this object. 1239 * refcnt - Reference count access to this object. 1240 * dead - Do not attempt to use this object. 1241 */ 1242 refcount_t refcnt; 1243 bool dead; 1244 1245 /* What socket does this endpoint belong to? */ 1246 struct sock *sk; 1247 1248 /* This is where we receive inbound chunks. */ 1249 struct sctp_inq inqueue; 1250 1251 /* This substructure includes the defining parameters of the 1252 * endpoint: 1253 * bind_addr.port is our shared port number. 1254 * bind_addr.address_list is our set of local IP addresses. 1255 */ 1256 struct sctp_bind_addr bind_addr; 1257 }; 1258 1259 1260 /* RFC Section 1.4 Key Terms 1261 * 1262 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a 1263 * multi-homed host, an SCTP endpoint is represented to its peers as a 1264 * combination of a set of eligible destination transport addresses to 1265 * which SCTP packets can be sent and a set of eligible source 1266 * transport addresses from which SCTP packets can be received. 1267 * All transport addresses used by an SCTP endpoint must use the 1268 * same port number, but can use multiple IP addresses. A transport 1269 * address used by an SCTP endpoint must not be used by another 1270 * SCTP endpoint. In other words, a transport address is unique 1271 * to an SCTP endpoint. 1272 * 1273 * From an implementation perspective, each socket has one of these. 1274 * A TCP-style socket will have exactly one association on one of 1275 * these. An UDP-style socket will have multiple associations hanging 1276 * off one of these. 1277 */ 1278 1279 struct sctp_endpoint { 1280 /* Common substructure for endpoint and association. */ 1281 struct sctp_ep_common base; 1282 1283 /* Associations: A list of current associations and mappings 1284 * to the data consumers for each association. This 1285 * may be in the form of a hash table or other 1286 * implementation dependent structure. The data 1287 * consumers may be process identification 1288 * information such as file descriptors, named pipe 1289 * pointer, or table pointers dependent on how SCTP 1290 * is implemented. 1291 */ 1292 /* This is really a list of struct sctp_association entries. */ 1293 struct list_head asocs; 1294 1295 /* Secret Key: A secret key used by this endpoint to compute 1296 * the MAC. This SHOULD be a cryptographic quality 1297 * random number with a sufficient length. 1298 * Discussion in [RFC1750] can be helpful in 1299 * selection of the key. 1300 */ 1301 __u8 secret_key[SCTP_SECRET_SIZE]; 1302 1303 /* digest: This is a digest of the sctp cookie. This field is 1304 * only used on the receive path when we try to validate 1305 * that the cookie has not been tampered with. We put 1306 * this here so we pre-allocate this once and can re-use 1307 * on every receive. 1308 */ 1309 __u8 *digest; 1310 1311 /* sendbuf acct. policy. */ 1312 __u32 sndbuf_policy; 1313 1314 /* rcvbuf acct. policy. */ 1315 __u32 rcvbuf_policy; 1316 1317 /* SCTP AUTH: array of the HMACs that will be allocated 1318 * we need this per association so that we don't serialize 1319 */ 1320 struct crypto_shash **auth_hmacs; 1321 1322 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */ 1323 struct sctp_hmac_algo_param *auth_hmacs_list; 1324 1325 /* SCTP-AUTH: chunks to authenticate encoded into parameter */ 1326 struct sctp_chunks_param *auth_chunk_list; 1327 1328 /* SCTP-AUTH: endpoint shared keys */ 1329 struct list_head endpoint_shared_keys; 1330 __u16 active_key_id; 1331 __u8 auth_enable:1, 1332 prsctp_enable:1, 1333 reconf_enable:1; 1334 1335 __u8 strreset_enable; 1336 1337 /* Security identifiers from incoming (INIT). These are set by 1338 * security_sctp_assoc_request(). These will only be used by 1339 * SCTP TCP type sockets and peeled off connections as they 1340 * cause a new socket to be generated. security_sctp_sk_clone() 1341 * will then plug these into the new socket. 1342 */ 1343 1344 u32 secid; 1345 u32 peer_secid; 1346 }; 1347 1348 /* Recover the outter endpoint structure. */ 1349 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base) 1350 { 1351 struct sctp_endpoint *ep; 1352 1353 ep = container_of(base, struct sctp_endpoint, base); 1354 return ep; 1355 } 1356 1357 /* These are function signatures for manipulating endpoints. */ 1358 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t); 1359 void sctp_endpoint_free(struct sctp_endpoint *); 1360 void sctp_endpoint_put(struct sctp_endpoint *); 1361 void sctp_endpoint_hold(struct sctp_endpoint *); 1362 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *); 1363 struct sctp_association *sctp_endpoint_lookup_assoc( 1364 const struct sctp_endpoint *ep, 1365 const union sctp_addr *paddr, 1366 struct sctp_transport **); 1367 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep, 1368 const union sctp_addr *paddr); 1369 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *, 1370 struct net *, const union sctp_addr *); 1371 bool sctp_has_association(struct net *net, const union sctp_addr *laddr, 1372 const union sctp_addr *paddr); 1373 1374 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep, 1375 const struct sctp_association *asoc, 1376 enum sctp_cid cid, struct sctp_init_chunk *peer_init, 1377 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk); 1378 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk, 1379 const union sctp_addr *peer, 1380 struct sctp_init_chunk *init, gfp_t gfp); 1381 __u32 sctp_generate_tag(const struct sctp_endpoint *); 1382 __u32 sctp_generate_tsn(const struct sctp_endpoint *); 1383 1384 struct sctp_inithdr_host { 1385 __u32 init_tag; 1386 __u32 a_rwnd; 1387 __u16 num_outbound_streams; 1388 __u16 num_inbound_streams; 1389 __u32 initial_tsn; 1390 }; 1391 1392 struct sctp_stream_priorities { 1393 /* List of priorities scheduled */ 1394 struct list_head prio_sched; 1395 /* List of streams scheduled */ 1396 struct list_head active; 1397 /* The next stream stream in line */ 1398 struct sctp_stream_out_ext *next; 1399 __u16 prio; 1400 }; 1401 1402 struct sctp_stream_out_ext { 1403 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 1404 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 1405 struct list_head outq; /* chunks enqueued by this stream */ 1406 union { 1407 struct { 1408 /* Scheduled streams list */ 1409 struct list_head prio_list; 1410 struct sctp_stream_priorities *prio_head; 1411 }; 1412 /* Fields used by RR scheduler */ 1413 struct { 1414 struct list_head rr_list; 1415 }; 1416 }; 1417 }; 1418 1419 struct sctp_stream_out { 1420 union { 1421 __u32 mid; 1422 __u16 ssn; 1423 }; 1424 __u32 mid_uo; 1425 struct sctp_stream_out_ext *ext; 1426 __u8 state; 1427 }; 1428 1429 struct sctp_stream_in { 1430 union { 1431 __u32 mid; 1432 __u16 ssn; 1433 }; 1434 __u32 mid_uo; 1435 __u32 fsn; 1436 __u32 fsn_uo; 1437 char pd_mode; 1438 char pd_mode_uo; 1439 }; 1440 1441 struct sctp_stream { 1442 struct flex_array *out; 1443 struct flex_array *in; 1444 __u16 outcnt; 1445 __u16 incnt; 1446 /* Current stream being sent, if any */ 1447 struct sctp_stream_out *out_curr; 1448 union { 1449 /* Fields used by priority scheduler */ 1450 struct { 1451 /* List of priorities scheduled */ 1452 struct list_head prio_list; 1453 }; 1454 /* Fields used by RR scheduler */ 1455 struct { 1456 /* List of streams scheduled */ 1457 struct list_head rr_list; 1458 /* The next stream stream in line */ 1459 struct sctp_stream_out_ext *rr_next; 1460 }; 1461 }; 1462 struct sctp_stream_interleave *si; 1463 }; 1464 1465 static inline struct sctp_stream_out *sctp_stream_out( 1466 const struct sctp_stream *stream, 1467 __u16 sid) 1468 { 1469 return flex_array_get(stream->out, sid); 1470 } 1471 1472 static inline struct sctp_stream_in *sctp_stream_in( 1473 const struct sctp_stream *stream, 1474 __u16 sid) 1475 { 1476 return flex_array_get(stream->in, sid); 1477 } 1478 1479 #define SCTP_SO(s, i) sctp_stream_out((s), (i)) 1480 #define SCTP_SI(s, i) sctp_stream_in((s), (i)) 1481 1482 #define SCTP_STREAM_CLOSED 0x00 1483 #define SCTP_STREAM_OPEN 0x01 1484 1485 static inline __u16 sctp_datachk_len(const struct sctp_stream *stream) 1486 { 1487 return stream->si->data_chunk_len; 1488 } 1489 1490 static inline __u16 sctp_datahdr_len(const struct sctp_stream *stream) 1491 { 1492 return stream->si->data_chunk_len - sizeof(struct sctp_chunkhdr); 1493 } 1494 1495 static inline __u16 sctp_ftsnchk_len(const struct sctp_stream *stream) 1496 { 1497 return stream->si->ftsn_chunk_len; 1498 } 1499 1500 static inline __u16 sctp_ftsnhdr_len(const struct sctp_stream *stream) 1501 { 1502 return stream->si->ftsn_chunk_len - sizeof(struct sctp_chunkhdr); 1503 } 1504 1505 /* SCTP_GET_ASSOC_STATS counters */ 1506 struct sctp_priv_assoc_stats { 1507 /* Maximum observed rto in the association during subsequent 1508 * observations. Value is set to 0 if no RTO measurement took place 1509 * The transport where the max_rto was observed is returned in 1510 * obs_rto_ipaddr 1511 */ 1512 struct sockaddr_storage obs_rto_ipaddr; 1513 __u64 max_obs_rto; 1514 /* Total In and Out SACKs received and sent */ 1515 __u64 isacks; 1516 __u64 osacks; 1517 /* Total In and Out packets received and sent */ 1518 __u64 opackets; 1519 __u64 ipackets; 1520 /* Total retransmitted chunks */ 1521 __u64 rtxchunks; 1522 /* TSN received > next expected */ 1523 __u64 outofseqtsns; 1524 /* Duplicate Chunks received */ 1525 __u64 idupchunks; 1526 /* Gap Ack Blocks received */ 1527 __u64 gapcnt; 1528 /* Unordered data chunks sent and received */ 1529 __u64 ouodchunks; 1530 __u64 iuodchunks; 1531 /* Ordered data chunks sent and received */ 1532 __u64 oodchunks; 1533 __u64 iodchunks; 1534 /* Control chunks sent and received */ 1535 __u64 octrlchunks; 1536 __u64 ictrlchunks; 1537 }; 1538 1539 /* RFC2960 1540 * 1541 * 12. Recommended Transmission Control Block (TCB) Parameters 1542 * 1543 * This section details a recommended set of parameters that should 1544 * be contained within the TCB for an implementation. This section is 1545 * for illustrative purposes and should not be deemed as requirements 1546 * on an implementation or as an exhaustive list of all parameters 1547 * inside an SCTP TCB. Each implementation may need its own additional 1548 * parameters for optimization. 1549 */ 1550 1551 1552 /* Here we have information about each individual association. */ 1553 struct sctp_association { 1554 1555 /* A base structure common to endpoint and association. 1556 * In this context, it represents the associations's view 1557 * of the local endpoint of the association. 1558 */ 1559 struct sctp_ep_common base; 1560 1561 /* Associations on the same socket. */ 1562 struct list_head asocs; 1563 1564 /* association id. */ 1565 sctp_assoc_t assoc_id; 1566 1567 /* This is our parent endpoint. */ 1568 struct sctp_endpoint *ep; 1569 1570 /* These are those association elements needed in the cookie. */ 1571 struct sctp_cookie c; 1572 1573 /* This is all information about our peer. */ 1574 struct { 1575 /* transport_addr_list 1576 * 1577 * Peer : A list of SCTP transport addresses that the 1578 * Transport : peer is bound to. This information is derived 1579 * Address : from the INIT or INIT ACK and is used to 1580 * List : associate an inbound packet with a given 1581 * : association. Normally this information is 1582 * : hashed or keyed for quick lookup and access 1583 * : of the TCB. 1584 * : The list is also initialized with the list 1585 * : of addresses passed with the sctp_connectx() 1586 * : call. 1587 * 1588 * It is a list of SCTP_transport's. 1589 */ 1590 struct list_head transport_addr_list; 1591 1592 /* rwnd 1593 * 1594 * Peer Rwnd : Current calculated value of the peer's rwnd. 1595 */ 1596 __u32 rwnd; 1597 1598 /* transport_count 1599 * 1600 * Peer : A count of the number of peer addresses 1601 * Transport : in the Peer Transport Address List. 1602 * Address : 1603 * Count : 1604 */ 1605 __u16 transport_count; 1606 1607 /* port 1608 * The transport layer port number. 1609 */ 1610 __u16 port; 1611 1612 /* primary_path 1613 * 1614 * Primary : This is the current primary destination 1615 * Path : transport address of the peer endpoint. It 1616 * : may also specify a source transport address 1617 * : on this endpoint. 1618 * 1619 * All of these paths live on transport_addr_list. 1620 * 1621 * At the bakeoffs, we discovered that the intent of 1622 * primaryPath is that it only changes when the ULP 1623 * asks to have it changed. We add the activePath to 1624 * designate the connection we are currently using to 1625 * transmit new data and most control chunks. 1626 */ 1627 struct sctp_transport *primary_path; 1628 1629 /* Cache the primary path address here, when we 1630 * need a an address for msg_name. 1631 */ 1632 union sctp_addr primary_addr; 1633 1634 /* active_path 1635 * The path that we are currently using to 1636 * transmit new data and most control chunks. 1637 */ 1638 struct sctp_transport *active_path; 1639 1640 /* retran_path 1641 * 1642 * RFC2960 6.4 Multi-homed SCTP Endpoints 1643 * ... 1644 * Furthermore, when its peer is multi-homed, an 1645 * endpoint SHOULD try to retransmit a chunk to an 1646 * active destination transport address that is 1647 * different from the last destination address to 1648 * which the DATA chunk was sent. 1649 */ 1650 struct sctp_transport *retran_path; 1651 1652 /* Pointer to last transport I have sent on. */ 1653 struct sctp_transport *last_sent_to; 1654 1655 /* This is the last transport I have received DATA on. */ 1656 struct sctp_transport *last_data_from; 1657 1658 /* 1659 * Mapping An array of bits or bytes indicating which out of 1660 * Array order TSN's have been received (relative to the 1661 * Last Rcvd TSN). If no gaps exist, i.e. no out of 1662 * order packets have been received, this array 1663 * will be set to all zero. This structure may be 1664 * in the form of a circular buffer or bit array. 1665 * 1666 * Last Rcvd : This is the last TSN received in 1667 * TSN : sequence. This value is set initially by 1668 * : taking the peer's Initial TSN, received in 1669 * : the INIT or INIT ACK chunk, and subtracting 1670 * : one from it. 1671 * 1672 * Throughout most of the specification this is called the 1673 * "Cumulative TSN ACK Point". In this case, we 1674 * ignore the advice in 12.2 in favour of the term 1675 * used in the bulk of the text. This value is hidden 1676 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn(). 1677 */ 1678 struct sctp_tsnmap tsn_map; 1679 1680 /* This mask is used to disable sending the ASCONF chunk 1681 * with specified parameter to peer. 1682 */ 1683 __be16 addip_disabled_mask; 1684 1685 /* These are capabilities which our peer advertised. */ 1686 __u8 ecn_capable:1, /* Can peer do ECN? */ 1687 ipv4_address:1, /* Peer understands IPv4 addresses? */ 1688 ipv6_address:1, /* Peer understands IPv6 addresses? */ 1689 hostname_address:1, /* Peer understands DNS addresses? */ 1690 asconf_capable:1, /* Does peer support ADDIP? */ 1691 prsctp_capable:1, /* Can peer do PR-SCTP? */ 1692 reconf_capable:1, /* Can peer do RE-CONFIG? */ 1693 auth_capable:1; /* Is peer doing SCTP-AUTH? */ 1694 1695 /* sack_needed : This flag indicates if the next received 1696 * : packet is to be responded to with a 1697 * : SACK. This is initialized to 0. When a packet 1698 * : is received sack_cnt is incremented. If this value 1699 * : reaches 2 or more, a SACK is sent and the 1700 * : value is reset to 0. Note: This is used only 1701 * : when no DATA chunks are received out of 1702 * : order. When DATA chunks are out of order, 1703 * : SACK's are not delayed (see Section 6). 1704 */ 1705 __u8 sack_needed:1, /* Do we need to sack the peer? */ 1706 sack_generation:1, 1707 zero_window_announced:1; 1708 __u32 sack_cnt; 1709 1710 __u32 adaptation_ind; /* Adaptation Code point. */ 1711 1712 struct sctp_inithdr_host i; 1713 void *cookie; 1714 int cookie_len; 1715 1716 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. 1717 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the 1718 * Initial TSN Value minus 1 1719 */ 1720 __u32 addip_serial; 1721 1722 /* SCTP-AUTH: We need to know pears random number, hmac list 1723 * and authenticated chunk list. All that is part of the 1724 * cookie and these are just pointers to those locations 1725 */ 1726 struct sctp_random_param *peer_random; 1727 struct sctp_chunks_param *peer_chunks; 1728 struct sctp_hmac_algo_param *peer_hmacs; 1729 } peer; 1730 1731 /* State : A state variable indicating what state the 1732 * : association is in, i.e. COOKIE-WAIT, 1733 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING, 1734 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT. 1735 * 1736 * Note: No "CLOSED" state is illustrated since if a 1737 * association is "CLOSED" its TCB SHOULD be removed. 1738 * 1739 * In this implementation we DO have a CLOSED 1740 * state which is used during initiation and shutdown. 1741 * 1742 * State takes values from SCTP_STATE_*. 1743 */ 1744 enum sctp_state state; 1745 1746 /* Overall : The overall association error count. 1747 * Error Count : [Clear this any time I get something.] 1748 */ 1749 int overall_error_count; 1750 1751 /* The cookie life I award for any cookie. */ 1752 ktime_t cookie_life; 1753 1754 /* These are the association's initial, max, and min RTO values. 1755 * These values will be initialized by system defaults, but can 1756 * be modified via the SCTP_RTOINFO socket option. 1757 */ 1758 unsigned long rto_initial; 1759 unsigned long rto_max; 1760 unsigned long rto_min; 1761 1762 /* Maximum number of new data packets that can be sent in a burst. */ 1763 int max_burst; 1764 1765 /* This is the max_retrans value for the association. This value will 1766 * be initialized initialized from system defaults, but can be 1767 * modified by the SCTP_ASSOCINFO socket option. 1768 */ 1769 int max_retrans; 1770 1771 /* This is the partially failed retrans value for the transport 1772 * and will be initialized from the assocs value. This can be 1773 * changed using the SCTP_PEER_ADDR_THLDS socket option 1774 */ 1775 int pf_retrans; 1776 1777 /* Maximum number of times the endpoint will retransmit INIT */ 1778 __u16 max_init_attempts; 1779 1780 /* How many times have we resent an INIT? */ 1781 __u16 init_retries; 1782 1783 /* The largest timeout or RTO value to use in attempting an INIT */ 1784 unsigned long max_init_timeo; 1785 1786 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 1787 * the destination address every heartbeat interval. This value 1788 * will be inherited by all new transports. 1789 */ 1790 unsigned long hbinterval; 1791 1792 /* This is the max_retrans value for new transports in the 1793 * association. 1794 */ 1795 __u16 pathmaxrxt; 1796 1797 __u32 flowlabel; 1798 __u8 dscp; 1799 1800 /* Flag that path mtu update is pending */ 1801 __u8 pmtu_pending; 1802 1803 /* Association : The smallest PMTU discovered for all of the 1804 * PMTU : peer's transport addresses. 1805 */ 1806 __u32 pathmtu; 1807 1808 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 1809 __u32 param_flags; 1810 1811 __u32 sackfreq; 1812 /* SACK delay timeout */ 1813 unsigned long sackdelay; 1814 1815 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES]; 1816 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES]; 1817 1818 /* Transport to which SHUTDOWN chunk was last sent. */ 1819 struct sctp_transport *shutdown_last_sent_to; 1820 1821 /* Transport to which INIT chunk was last sent. */ 1822 struct sctp_transport *init_last_sent_to; 1823 1824 /* How many times have we resent a SHUTDOWN */ 1825 int shutdown_retries; 1826 1827 /* Next TSN : The next TSN number to be assigned to a new 1828 * : DATA chunk. This is sent in the INIT or INIT 1829 * : ACK chunk to the peer and incremented each 1830 * : time a DATA chunk is assigned a TSN 1831 * : (normally just prior to transmit or during 1832 * : fragmentation). 1833 */ 1834 __u32 next_tsn; 1835 1836 /* 1837 * Last Rcvd : This is the last TSN received in sequence. This value 1838 * TSN : is set initially by taking the peer's Initial TSN, 1839 * : received in the INIT or INIT ACK chunk, and 1840 * : subtracting one from it. 1841 * 1842 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point. 1843 */ 1844 1845 __u32 ctsn_ack_point; 1846 1847 /* PR-SCTP Advanced.Peer.Ack.Point */ 1848 __u32 adv_peer_ack_point; 1849 1850 /* Highest TSN that is acknowledged by incoming SACKs. */ 1851 __u32 highest_sacked; 1852 1853 /* TSN marking the fast recovery exit point */ 1854 __u32 fast_recovery_exit; 1855 1856 /* Flag to track the current fast recovery state */ 1857 __u8 fast_recovery; 1858 1859 /* The number of unacknowledged data chunks. Reported through 1860 * the SCTP_STATUS sockopt. 1861 */ 1862 __u16 unack_data; 1863 1864 /* The total number of data chunks that we've had to retransmit 1865 * as the result of a T3 timer expiration 1866 */ 1867 __u32 rtx_data_chunks; 1868 1869 /* This is the association's receive buffer space. This value is used 1870 * to set a_rwnd field in an INIT or a SACK chunk. 1871 */ 1872 __u32 rwnd; 1873 1874 /* This is the last advertised value of rwnd over a SACK chunk. */ 1875 __u32 a_rwnd; 1876 1877 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed 1878 * to slop over a maximum of the association's frag_point. 1879 */ 1880 __u32 rwnd_over; 1881 1882 /* Keeps treack of rwnd pressure. This happens when we have 1883 * a window, but not recevie buffer (i.e small packets). This one 1884 * is releases slowly (1 PMTU at a time ). 1885 */ 1886 __u32 rwnd_press; 1887 1888 /* This is the sndbuf size in use for the association. 1889 * This corresponds to the sndbuf size for the association, 1890 * as specified in the sk->sndbuf. 1891 */ 1892 int sndbuf_used; 1893 1894 /* This is the amount of memory that this association has allocated 1895 * in the receive path at any given time. 1896 */ 1897 atomic_t rmem_alloc; 1898 1899 /* This is the wait queue head for send requests waiting on 1900 * the association sndbuf space. 1901 */ 1902 wait_queue_head_t wait; 1903 1904 /* The message size at which SCTP fragmentation will occur. */ 1905 __u32 frag_point; 1906 __u32 user_frag; 1907 1908 /* Counter used to count INIT errors. */ 1909 int init_err_counter; 1910 1911 /* Count the number of INIT cycles (for doubling timeout). */ 1912 int init_cycle; 1913 1914 /* Default send parameters. */ 1915 __u16 default_stream; 1916 __u16 default_flags; 1917 __u32 default_ppid; 1918 __u32 default_context; 1919 __u32 default_timetolive; 1920 1921 /* Default receive parameters */ 1922 __u32 default_rcv_context; 1923 1924 /* Stream arrays */ 1925 struct sctp_stream stream; 1926 1927 /* All outbound chunks go through this structure. */ 1928 struct sctp_outq outqueue; 1929 1930 /* A smart pipe that will handle reordering and fragmentation, 1931 * as well as handle passing events up to the ULP. 1932 */ 1933 struct sctp_ulpq ulpq; 1934 1935 /* Last TSN that caused an ECNE Chunk to be sent. */ 1936 __u32 last_ecne_tsn; 1937 1938 /* Last TSN that caused a CWR Chunk to be sent. */ 1939 __u32 last_cwr_tsn; 1940 1941 /* How many duplicated TSNs have we seen? */ 1942 int numduptsns; 1943 1944 /* These are to support 1945 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses 1946 * and Enforcement of Flow and Message Limits" 1947 * <draft-ietf-tsvwg-addip-sctp-02.txt> 1948 * or "ADDIP" for short. 1949 */ 1950 1951 1952 1953 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1954 * 1955 * R1) One and only one ASCONF Chunk MAY be in transit and 1956 * unacknowledged at any one time. If a sender, after sending 1957 * an ASCONF chunk, decides it needs to transfer another 1958 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1959 * returns from the previous ASCONF Chunk before sending a 1960 * subsequent ASCONF. Note this restriction binds each side, 1961 * so at any time two ASCONF may be in-transit on any given 1962 * association (one sent from each endpoint). 1963 * 1964 * [This is our one-and-only-one ASCONF in flight. If we do 1965 * not have an ASCONF in flight, this is NULL.] 1966 */ 1967 struct sctp_chunk *addip_last_asconf; 1968 1969 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk. 1970 * 1971 * This is needed to implement itmes E1 - E4 of the updated 1972 * spec. Here is the justification: 1973 * 1974 * Since the peer may bundle multiple ASCONF chunks toward us, 1975 * we now need the ability to cache multiple ACKs. The section 1976 * describes in detail how they are cached and cleaned up. 1977 */ 1978 struct list_head asconf_ack_list; 1979 1980 /* These ASCONF chunks are waiting to be sent. 1981 * 1982 * These chunaks can't be pushed to outqueue until receiving 1983 * ASCONF_ACK for the previous ASCONF indicated by 1984 * addip_last_asconf, so as to guarantee that only one ASCONF 1985 * is in flight at any time. 1986 * 1987 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1988 * 1989 * In defining the ASCONF Chunk transfer procedures, it is 1990 * essential that these transfers MUST NOT cause congestion 1991 * within the network. To achieve this, we place these 1992 * restrictions on the transfer of ASCONF Chunks: 1993 * 1994 * R1) One and only one ASCONF Chunk MAY be in transit and 1995 * unacknowledged at any one time. If a sender, after sending 1996 * an ASCONF chunk, decides it needs to transfer another 1997 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1998 * returns from the previous ASCONF Chunk before sending a 1999 * subsequent ASCONF. Note this restriction binds each side, 2000 * so at any time two ASCONF may be in-transit on any given 2001 * association (one sent from each endpoint). 2002 * 2003 * 2004 * [I really think this is EXACTLY the sort of intelligence 2005 * which already resides in sctp_outq. Please move this 2006 * queue and its supporting logic down there. --piggy] 2007 */ 2008 struct list_head addip_chunk_list; 2009 2010 /* ADDIP Section 4.1 ASCONF Chunk Procedures 2011 * 2012 * A2) A serial number should be assigned to the Chunk. The 2013 * serial number SHOULD be a monotonically increasing 2014 * number. The serial number SHOULD be initialized at 2015 * the start of the association to the same value as the 2016 * Initial TSN and every time a new ASCONF chunk is created 2017 * it is incremented by one after assigning the serial number 2018 * to the newly created chunk. 2019 * 2020 * ADDIP 2021 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF) 2022 * 2023 * Serial Number : 32 bits (unsigned integer) 2024 * 2025 * This value represents a Serial Number for the ASCONF 2026 * Chunk. The valid range of Serial Number is from 0 to 2027 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0 2028 * after reaching 4294967295. 2029 */ 2030 __u32 addip_serial; 2031 int src_out_of_asoc_ok; 2032 union sctp_addr *asconf_addr_del_pending; 2033 struct sctp_transport *new_transport; 2034 2035 /* SCTP AUTH: list of the endpoint shared keys. These 2036 * keys are provided out of band by the user applicaton 2037 * and can't change during the lifetime of the association 2038 */ 2039 struct list_head endpoint_shared_keys; 2040 2041 /* SCTP AUTH: 2042 * The current generated assocaition shared key (secret) 2043 */ 2044 struct sctp_auth_bytes *asoc_shared_key; 2045 struct sctp_shared_key *shkey; 2046 2047 /* SCTP AUTH: hmac id of the first peer requested algorithm 2048 * that we support. 2049 */ 2050 __u16 default_hmac_id; 2051 2052 __u16 active_key_id; 2053 2054 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */ 2055 temp:1, /* Is it a temporary association? */ 2056 force_delay:1, 2057 intl_enable:1, 2058 prsctp_enable:1, 2059 reconf_enable:1; 2060 2061 __u8 strreset_enable; 2062 __u8 strreset_outstanding; /* request param count on the fly */ 2063 2064 __u32 strreset_outseq; /* Update after receiving response */ 2065 __u32 strreset_inseq; /* Update after receiving request */ 2066 __u32 strreset_result[2]; /* save the results of last 2 responses */ 2067 2068 struct sctp_chunk *strreset_chunk; /* save request chunk */ 2069 2070 struct sctp_priv_assoc_stats stats; 2071 2072 int sent_cnt_removable; 2073 2074 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 2075 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 2076 }; 2077 2078 2079 /* An eyecatcher for determining if we are really looking at an 2080 * association data structure. 2081 */ 2082 enum { 2083 SCTP_ASSOC_EYECATCHER = 0xa550c123, 2084 }; 2085 2086 /* Recover the outter association structure. */ 2087 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base) 2088 { 2089 struct sctp_association *asoc; 2090 2091 asoc = container_of(base, struct sctp_association, base); 2092 return asoc; 2093 } 2094 2095 /* These are function signatures for manipulating associations. */ 2096 2097 2098 struct sctp_association * 2099 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk, 2100 enum sctp_scope scope, gfp_t gfp); 2101 void sctp_association_free(struct sctp_association *); 2102 void sctp_association_put(struct sctp_association *); 2103 void sctp_association_hold(struct sctp_association *); 2104 2105 struct sctp_transport *sctp_assoc_choose_alter_transport( 2106 struct sctp_association *, struct sctp_transport *); 2107 void sctp_assoc_update_retran_path(struct sctp_association *); 2108 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *, 2109 const union sctp_addr *); 2110 int sctp_assoc_lookup_laddr(struct sctp_association *asoc, 2111 const union sctp_addr *laddr); 2112 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *, 2113 const union sctp_addr *address, 2114 const gfp_t gfp, 2115 const int peer_state); 2116 void sctp_assoc_del_peer(struct sctp_association *asoc, 2117 const union sctp_addr *addr); 2118 void sctp_assoc_rm_peer(struct sctp_association *asoc, 2119 struct sctp_transport *peer); 2120 void sctp_assoc_control_transport(struct sctp_association *asoc, 2121 struct sctp_transport *transport, 2122 enum sctp_transport_cmd command, 2123 sctp_sn_error_t error); 2124 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32); 2125 void sctp_assoc_migrate(struct sctp_association *, struct sock *); 2126 int sctp_assoc_update(struct sctp_association *old, 2127 struct sctp_association *new); 2128 2129 __u32 sctp_association_get_next_tsn(struct sctp_association *); 2130 2131 void sctp_assoc_update_frag_point(struct sctp_association *asoc); 2132 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu); 2133 void sctp_assoc_sync_pmtu(struct sctp_association *asoc); 2134 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int); 2135 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int); 2136 void sctp_assoc_set_primary(struct sctp_association *, 2137 struct sctp_transport *); 2138 void sctp_assoc_del_nonprimary_peers(struct sctp_association *, 2139 struct sctp_transport *); 2140 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, 2141 enum sctp_scope scope, gfp_t gfp); 2142 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *, 2143 struct sctp_cookie*, 2144 gfp_t gfp); 2145 int sctp_assoc_set_id(struct sctp_association *, gfp_t); 2146 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc); 2147 struct sctp_chunk *sctp_assoc_lookup_asconf_ack( 2148 const struct sctp_association *asoc, 2149 __be32 serial); 2150 void sctp_asconf_queue_teardown(struct sctp_association *asoc); 2151 2152 int sctp_cmp_addr_exact(const union sctp_addr *ss1, 2153 const union sctp_addr *ss2); 2154 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc); 2155 2156 /* A convenience structure to parse out SCTP specific CMSGs. */ 2157 struct sctp_cmsgs { 2158 struct sctp_initmsg *init; 2159 struct sctp_sndrcvinfo *srinfo; 2160 struct sctp_sndinfo *sinfo; 2161 struct sctp_prinfo *prinfo; 2162 struct sctp_authinfo *authinfo; 2163 struct msghdr *addrs_msg; 2164 }; 2165 2166 /* Structure for tracking memory objects */ 2167 struct sctp_dbg_objcnt_entry { 2168 char *label; 2169 atomic_t *counter; 2170 }; 2171 2172 #endif /* __sctp_structs_h__ */ 2173