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 signed char fastreuse; 100 signed char fastreuseport; 101 kuid_t fastuid; 102 struct hlist_node node; 103 struct hlist_head owner; 104 struct net *net; 105 }; 106 107 struct sctp_bind_hashbucket { 108 spinlock_t lock; 109 struct hlist_head chain; 110 }; 111 112 /* Used for hashing all associations. */ 113 struct sctp_hashbucket { 114 rwlock_t lock; 115 struct hlist_head chain; 116 } __attribute__((__aligned__(8))); 117 118 119 /* The SCTP globals structure. */ 120 extern struct sctp_globals { 121 /* This is a list of groups of functions for each address 122 * family that we support. 123 */ 124 struct list_head address_families; 125 126 /* This is the hash of all endpoints. */ 127 struct sctp_hashbucket *ep_hashtable; 128 /* This is the sctp port control hash. */ 129 struct sctp_bind_hashbucket *port_hashtable; 130 /* This is the hash of all transports. */ 131 struct rhltable transport_hashtable; 132 133 /* Sizes of above hashtables. */ 134 int ep_hashsize; 135 int port_hashsize; 136 137 /* Default initialization values to be applied to new associations. */ 138 __u16 max_instreams; 139 __u16 max_outstreams; 140 141 /* Flag to indicate whether computing and verifying checksum 142 * is disabled. */ 143 bool checksum_disable; 144 } sctp_globals; 145 146 #define sctp_max_instreams (sctp_globals.max_instreams) 147 #define sctp_max_outstreams (sctp_globals.max_outstreams) 148 #define sctp_address_families (sctp_globals.address_families) 149 #define sctp_ep_hashsize (sctp_globals.ep_hashsize) 150 #define sctp_ep_hashtable (sctp_globals.ep_hashtable) 151 #define sctp_port_hashsize (sctp_globals.port_hashsize) 152 #define sctp_port_hashtable (sctp_globals.port_hashtable) 153 #define sctp_transport_hashtable (sctp_globals.transport_hashtable) 154 #define sctp_checksum_disable (sctp_globals.checksum_disable) 155 156 /* SCTP Socket type: UDP or TCP style. */ 157 enum sctp_socket_type { 158 SCTP_SOCKET_UDP = 0, 159 SCTP_SOCKET_UDP_HIGH_BANDWIDTH, 160 SCTP_SOCKET_TCP 161 }; 162 163 /* Per socket SCTP information. */ 164 struct sctp_sock { 165 /* inet_sock has to be the first member of sctp_sock */ 166 struct inet_sock inet; 167 /* What kind of a socket is this? */ 168 enum sctp_socket_type type; 169 170 /* PF_ family specific functions. */ 171 struct sctp_pf *pf; 172 173 /* Access to HMAC transform. */ 174 struct crypto_shash *hmac; 175 char *sctp_hmac_alg; 176 177 /* What is our base endpointer? */ 178 struct sctp_endpoint *ep; 179 180 struct sctp_bind_bucket *bind_hash; 181 /* Various Socket Options. */ 182 __u16 default_stream; 183 __u32 default_ppid; 184 __u16 default_flags; 185 __u32 default_context; 186 __u32 default_timetolive; 187 __u32 default_rcv_context; 188 int max_burst; 189 190 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 191 * the destination address every heartbeat interval. This value 192 * will be inherited by all new associations. 193 */ 194 __u32 hbinterval; 195 196 /* This is the max_retrans value for new associations. */ 197 __u16 pathmaxrxt; 198 199 __u32 flowlabel; 200 __u8 dscp; 201 202 /* The initial Path MTU to use for new associations. */ 203 __u32 pathmtu; 204 205 /* The default SACK delay timeout for new associations. */ 206 __u32 sackdelay; 207 __u32 sackfreq; 208 209 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 210 __u32 param_flags; 211 212 struct sctp_rtoinfo rtoinfo; 213 struct sctp_paddrparams paddrparam; 214 struct sctp_assocparams assocparams; 215 216 /* 217 * These two structures must be grouped together for the usercopy 218 * whitelist region. 219 */ 220 __u16 subscribe; 221 struct sctp_initmsg initmsg; 222 223 int user_frag; 224 225 __u32 autoclose; 226 __u32 adaptation_ind; 227 __u32 pd_point; 228 __u16 nodelay:1, 229 reuse:1, 230 disable_fragments:1, 231 v4mapped:1, 232 frag_interleave:1, 233 strm_interleave:1, 234 recvrcvinfo:1, 235 recvnxtinfo:1, 236 data_ready_signalled:1; 237 238 atomic_t pd_mode; 239 /* Receive to here while partial delivery is in effect. */ 240 struct sk_buff_head pd_lobby; 241 242 /* These must be the last fields, as they will skipped on copies, 243 * like on accept and peeloff operations 244 */ 245 struct list_head auto_asconf_list; 246 int do_auto_asconf; 247 }; 248 249 static inline struct sctp_sock *sctp_sk(const struct sock *sk) 250 { 251 return (struct sctp_sock *)sk; 252 } 253 254 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp) 255 { 256 return (struct sock *)sp; 257 } 258 259 #if IS_ENABLED(CONFIG_IPV6) 260 struct sctp6_sock { 261 struct sctp_sock sctp; 262 struct ipv6_pinfo inet6; 263 }; 264 #endif /* CONFIG_IPV6 */ 265 266 267 /* This is our APPLICATION-SPECIFIC state cookie. 268 * THIS IS NOT DICTATED BY THE SPECIFICATION. 269 */ 270 /* These are the parts of an association which we send in the cookie. 271 * Most of these are straight out of: 272 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB) 273 * 274 */ 275 276 struct sctp_cookie { 277 278 /* My : Tag expected in every inbound packet and sent 279 * Verification: in the INIT or INIT ACK chunk. 280 * Tag : 281 */ 282 __u32 my_vtag; 283 284 /* Peer's : Tag expected in every outbound packet except 285 * Verification: in the INIT chunk. 286 * Tag : 287 */ 288 __u32 peer_vtag; 289 290 /* The rest of these are not from the spec, but really need to 291 * be in the cookie. 292 */ 293 294 /* My Tie Tag : Assist in discovering a restarting association. */ 295 __u32 my_ttag; 296 297 /* Peer's Tie Tag: Assist in discovering a restarting association. */ 298 __u32 peer_ttag; 299 300 /* When does this cookie expire? */ 301 ktime_t expiration; 302 303 /* Number of inbound/outbound streams which are set 304 * and negotiated during the INIT process. 305 */ 306 __u16 sinit_num_ostreams; 307 __u16 sinit_max_instreams; 308 309 /* This is the first sequence number I used. */ 310 __u32 initial_tsn; 311 312 /* This holds the originating address of the INIT packet. */ 313 union sctp_addr peer_addr; 314 315 /* IG Section 2.35.3 316 * Include the source port of the INIT-ACK 317 */ 318 __u16 my_port; 319 320 __u8 prsctp_capable; 321 322 /* Padding for future use */ 323 __u8 padding; 324 325 __u32 adaptation_ind; 326 327 __u8 auth_random[sizeof(struct sctp_paramhdr) + 328 SCTP_AUTH_RANDOM_LENGTH]; 329 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2]; 330 __u8 auth_chunks[sizeof(struct sctp_paramhdr) + SCTP_AUTH_MAX_CHUNKS]; 331 332 /* This is a shim for my peer's INIT packet, followed by 333 * a copy of the raw address list of the association. 334 * The length of the raw address list is saved in the 335 * raw_addr_list_len field, which will be used at the time when 336 * the association TCB is re-constructed from the cookie. 337 */ 338 __u32 raw_addr_list_len; 339 struct sctp_init_chunk peer_init[0]; 340 }; 341 342 343 /* The format of our cookie that we send to our peer. */ 344 struct sctp_signed_cookie { 345 __u8 signature[SCTP_SECRET_SIZE]; 346 __u32 __pad; /* force sctp_cookie alignment to 64 bits */ 347 struct sctp_cookie c; 348 } __packed; 349 350 /* This is another convenience type to allocate memory for address 351 * params for the maximum size and pass such structures around 352 * internally. 353 */ 354 union sctp_addr_param { 355 struct sctp_paramhdr p; 356 struct sctp_ipv4addr_param v4; 357 struct sctp_ipv6addr_param v6; 358 }; 359 360 /* A convenience type to allow walking through the various 361 * parameters and avoid casting all over the place. 362 */ 363 union sctp_params { 364 void *v; 365 struct sctp_paramhdr *p; 366 struct sctp_cookie_preserve_param *life; 367 struct sctp_hostname_param *dns; 368 struct sctp_cookie_param *cookie; 369 struct sctp_supported_addrs_param *sat; 370 struct sctp_ipv4addr_param *v4; 371 struct sctp_ipv6addr_param *v6; 372 union sctp_addr_param *addr; 373 struct sctp_adaptation_ind_param *aind; 374 struct sctp_supported_ext_param *ext; 375 struct sctp_random_param *random; 376 struct sctp_chunks_param *chunks; 377 struct sctp_hmac_algo_param *hmac_algo; 378 struct sctp_addip_param *addip; 379 }; 380 381 /* RFC 2960. Section 3.3.5 Heartbeat. 382 * Heartbeat Information: variable length 383 * The Sender-specific Heartbeat Info field should normally include 384 * information about the sender's current time when this HEARTBEAT 385 * chunk is sent and the destination transport address to which this 386 * HEARTBEAT is sent (see Section 8.3). 387 */ 388 struct sctp_sender_hb_info { 389 struct sctp_paramhdr param_hdr; 390 union sctp_addr daddr; 391 unsigned long sent_at; 392 __u64 hb_nonce; 393 }; 394 395 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt, 396 gfp_t gfp); 397 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid); 398 void sctp_stream_free(struct sctp_stream *stream); 399 void sctp_stream_clear(struct sctp_stream *stream); 400 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new); 401 402 /* What is the current SSN number for this stream? */ 403 #define sctp_ssn_peek(stream, type, sid) \ 404 (sctp_stream_##type((stream), (sid))->ssn) 405 406 /* Return the next SSN number for this stream. */ 407 #define sctp_ssn_next(stream, type, sid) \ 408 (sctp_stream_##type((stream), (sid))->ssn++) 409 410 /* Skip over this ssn and all below. */ 411 #define sctp_ssn_skip(stream, type, sid, ssn) \ 412 (sctp_stream_##type((stream), (sid))->ssn = ssn + 1) 413 414 /* What is the current MID number for this stream? */ 415 #define sctp_mid_peek(stream, type, sid) \ 416 (sctp_stream_##type((stream), (sid))->mid) 417 418 /* Return the next MID number for this stream. */ 419 #define sctp_mid_next(stream, type, sid) \ 420 (sctp_stream_##type((stream), (sid))->mid++) 421 422 /* Skip over this mid and all below. */ 423 #define sctp_mid_skip(stream, type, sid, mid) \ 424 (sctp_stream_##type((stream), (sid))->mid = mid + 1) 425 426 /* What is the current MID_uo number for this stream? */ 427 #define sctp_mid_uo_peek(stream, type, sid) \ 428 (sctp_stream_##type((stream), (sid))->mid_uo) 429 430 /* Return the next MID_uo number for this stream. */ 431 #define sctp_mid_uo_next(stream, type, sid) \ 432 (sctp_stream_##type((stream), (sid))->mid_uo++) 433 434 /* 435 * Pointers to address related SCTP functions. 436 * (i.e. things that depend on the address family.) 437 */ 438 struct sctp_af { 439 int (*sctp_xmit) (struct sk_buff *skb, 440 struct sctp_transport *); 441 int (*setsockopt) (struct sock *sk, 442 int level, 443 int optname, 444 char __user *optval, 445 unsigned int optlen); 446 int (*getsockopt) (struct sock *sk, 447 int level, 448 int optname, 449 char __user *optval, 450 int __user *optlen); 451 int (*compat_setsockopt) (struct sock *sk, 452 int level, 453 int optname, 454 char __user *optval, 455 unsigned int optlen); 456 int (*compat_getsockopt) (struct sock *sk, 457 int level, 458 int optname, 459 char __user *optval, 460 int __user *optlen); 461 void (*get_dst) (struct sctp_transport *t, 462 union sctp_addr *saddr, 463 struct flowi *fl, 464 struct sock *sk); 465 void (*get_saddr) (struct sctp_sock *sk, 466 struct sctp_transport *t, 467 struct flowi *fl); 468 void (*copy_addrlist) (struct list_head *, 469 struct net_device *); 470 int (*cmp_addr) (const union sctp_addr *addr1, 471 const union sctp_addr *addr2); 472 void (*addr_copy) (union sctp_addr *dst, 473 union sctp_addr *src); 474 void (*from_skb) (union sctp_addr *, 475 struct sk_buff *skb, 476 int saddr); 477 void (*from_sk) (union sctp_addr *, 478 struct sock *sk); 479 void (*from_addr_param) (union sctp_addr *, 480 union sctp_addr_param *, 481 __be16 port, int iif); 482 int (*to_addr_param) (const union sctp_addr *, 483 union sctp_addr_param *); 484 int (*addr_valid) (union sctp_addr *, 485 struct sctp_sock *, 486 const struct sk_buff *); 487 enum sctp_scope (*scope)(union sctp_addr *); 488 void (*inaddr_any) (union sctp_addr *, __be16); 489 int (*is_any) (const union sctp_addr *); 490 int (*available) (union sctp_addr *, 491 struct sctp_sock *); 492 int (*skb_iif) (const struct sk_buff *sk); 493 int (*is_ce) (const struct sk_buff *sk); 494 void (*seq_dump_addr)(struct seq_file *seq, 495 union sctp_addr *addr); 496 void (*ecn_capable)(struct sock *sk); 497 __u16 net_header_len; 498 int sockaddr_len; 499 int (*ip_options_len)(struct sock *sk); 500 sa_family_t sa_family; 501 struct list_head list; 502 }; 503 504 struct sctp_af *sctp_get_af_specific(sa_family_t); 505 int sctp_register_af(struct sctp_af *); 506 507 /* Protocol family functions. */ 508 struct sctp_pf { 509 void (*event_msgname)(struct sctp_ulpevent *, char *, int *); 510 void (*skb_msgname) (struct sk_buff *, char *, int *); 511 int (*af_supported) (sa_family_t, struct sctp_sock *); 512 int (*cmp_addr) (const union sctp_addr *, 513 const union sctp_addr *, 514 struct sctp_sock *); 515 int (*bind_verify) (struct sctp_sock *, union sctp_addr *); 516 int (*send_verify) (struct sctp_sock *, union sctp_addr *); 517 int (*supported_addrs)(const struct sctp_sock *, __be16 *); 518 struct sock *(*create_accept_sk) (struct sock *sk, 519 struct sctp_association *asoc, 520 bool kern); 521 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr); 522 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk); 523 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk); 524 void (*copy_ip_options)(struct sock *sk, struct sock *newsk); 525 struct sctp_af *af; 526 }; 527 528 529 /* Structure to track chunk fragments that have been acked, but peer 530 * fragments of the same message have not. 531 */ 532 struct sctp_datamsg { 533 /* Chunks waiting to be submitted to lower layer. */ 534 struct list_head chunks; 535 /* Reference counting. */ 536 refcount_t refcnt; 537 /* When is this message no longer interesting to the peer? */ 538 unsigned long expires_at; 539 /* Did the messenge fail to send? */ 540 int send_error; 541 u8 send_failed:1, 542 can_delay:1, /* should this message be Nagle delayed */ 543 abandoned:1; /* should this message be abandoned */ 544 }; 545 546 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *, 547 struct sctp_sndrcvinfo *, 548 struct iov_iter *); 549 void sctp_datamsg_free(struct sctp_datamsg *); 550 void sctp_datamsg_put(struct sctp_datamsg *); 551 void sctp_chunk_fail(struct sctp_chunk *, int error); 552 int sctp_chunk_abandoned(struct sctp_chunk *); 553 554 /* RFC2960 1.4 Key Terms 555 * 556 * o Chunk: A unit of information within an SCTP packet, consisting of 557 * a chunk header and chunk-specific content. 558 * 559 * As a matter of convenience, we remember the SCTP common header for 560 * each chunk as well as a few other header pointers... 561 */ 562 struct sctp_chunk { 563 struct list_head list; 564 565 refcount_t refcnt; 566 567 /* How many times this chunk have been sent, for prsctp RTX policy */ 568 int sent_count; 569 570 union { 571 /* This is our link to the per-transport transmitted list. */ 572 struct list_head transmitted_list; 573 /* List in specific stream outq */ 574 struct list_head stream_list; 575 }; 576 577 /* This field is used by chunks that hold fragmented data. 578 * For the first fragment this is the list that holds the rest of 579 * fragments. For the remaining fragments, this is the link to the 580 * frag_list maintained in the first fragment. 581 */ 582 struct list_head frag_list; 583 584 /* This points to the sk_buff containing the actual data. */ 585 struct sk_buff *skb; 586 587 union { 588 /* In case of GSO packets, this will store the head one */ 589 struct sk_buff *head_skb; 590 /* In case of auth enabled, this will point to the shkey */ 591 struct sctp_shared_key *shkey; 592 }; 593 594 /* These are the SCTP headers by reverse order in a packet. 595 * Note that some of these may happen more than once. In that 596 * case, we point at the "current" one, whatever that means 597 * for that level of header. 598 */ 599 600 /* We point this at the FIRST TLV parameter to chunk_hdr. */ 601 union sctp_params param_hdr; 602 union { 603 __u8 *v; 604 struct sctp_datahdr *data_hdr; 605 struct sctp_inithdr *init_hdr; 606 struct sctp_sackhdr *sack_hdr; 607 struct sctp_heartbeathdr *hb_hdr; 608 struct sctp_sender_hb_info *hbs_hdr; 609 struct sctp_shutdownhdr *shutdown_hdr; 610 struct sctp_signed_cookie *cookie_hdr; 611 struct sctp_ecnehdr *ecne_hdr; 612 struct sctp_cwrhdr *ecn_cwr_hdr; 613 struct sctp_errhdr *err_hdr; 614 struct sctp_addiphdr *addip_hdr; 615 struct sctp_fwdtsn_hdr *fwdtsn_hdr; 616 struct sctp_authhdr *auth_hdr; 617 struct sctp_idatahdr *idata_hdr; 618 struct sctp_ifwdtsn_hdr *ifwdtsn_hdr; 619 } subh; 620 621 __u8 *chunk_end; 622 623 struct sctp_chunkhdr *chunk_hdr; 624 struct sctphdr *sctp_hdr; 625 626 /* This needs to be recoverable for SCTP_SEND_FAILED events. */ 627 struct sctp_sndrcvinfo sinfo; 628 629 /* Which association does this belong to? */ 630 struct sctp_association *asoc; 631 632 /* What endpoint received this chunk? */ 633 struct sctp_ep_common *rcvr; 634 635 /* We fill this in if we are calculating RTT. */ 636 unsigned long sent_at; 637 638 /* What is the origin IP address for this chunk? */ 639 union sctp_addr source; 640 /* Destination address for this chunk. */ 641 union sctp_addr dest; 642 643 /* For outbound message, track all fragments for SEND_FAILED. */ 644 struct sctp_datamsg *msg; 645 646 /* For an inbound chunk, this tells us where it came from. 647 * For an outbound chunk, it tells us where we'd like it to 648 * go. It is NULL if we have no preference. 649 */ 650 struct sctp_transport *transport; 651 652 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO 653 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH 654 * spec violates the principle premis that all chunks are processed 655 * in order. 656 */ 657 struct sk_buff *auth_chunk; 658 659 #define SCTP_CAN_FRTX 0x0 660 #define SCTP_NEED_FRTX 0x1 661 #define SCTP_DONT_FRTX 0x2 662 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */ 663 has_tsn:1, /* Does this chunk have a TSN yet? */ 664 has_ssn:1, /* Does this chunk have a SSN yet? */ 665 #define has_mid has_ssn 666 singleton:1, /* Only chunk in the packet? */ 667 end_of_packet:1, /* Last chunk in the packet? */ 668 ecn_ce_done:1, /* Have we processed the ECN CE bit? */ 669 pdiscard:1, /* Discard the whole packet now? */ 670 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */ 671 data_accepted:1, /* At least 1 chunk accepted */ 672 auth:1, /* IN: was auth'ed | OUT: needs auth */ 673 has_asconf:1, /* IN: have seen an asconf before */ 674 tsn_missing_report:2, /* Data chunk missing counter. */ 675 fast_retransmit:2; /* Is this chunk fast retransmitted? */ 676 }; 677 678 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1) 679 void sctp_chunk_hold(struct sctp_chunk *); 680 void sctp_chunk_put(struct sctp_chunk *); 681 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len, 682 struct iov_iter *from); 683 void sctp_chunk_free(struct sctp_chunk *); 684 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data); 685 struct sctp_chunk *sctp_chunkify(struct sk_buff *, 686 const struct sctp_association *, 687 struct sock *, gfp_t gfp); 688 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *, 689 union sctp_addr *); 690 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk); 691 692 static inline __u16 sctp_chunk_stream_no(struct sctp_chunk *ch) 693 { 694 return ntohs(ch->subh.data_hdr->stream); 695 } 696 697 enum { 698 SCTP_ADDR_NEW, /* new address added to assoc/ep */ 699 SCTP_ADDR_SRC, /* address can be used as source */ 700 SCTP_ADDR_DEL, /* address about to be deleted */ 701 }; 702 703 /* This is a structure for holding either an IPv6 or an IPv4 address. */ 704 struct sctp_sockaddr_entry { 705 struct list_head list; 706 struct rcu_head rcu; 707 union sctp_addr a; 708 __u8 state; 709 __u8 valid; 710 }; 711 712 #define SCTP_ADDRESS_TICK_DELAY 500 713 714 /* This structure holds lists of chunks as we are assembling for 715 * transmission. 716 */ 717 struct sctp_packet { 718 /* These are the SCTP header values (host order) for the packet. */ 719 __u16 source_port; 720 __u16 destination_port; 721 __u32 vtag; 722 723 /* This contains the payload chunks. */ 724 struct list_head chunk_list; 725 726 /* This is the overhead of the sctp and ip headers. */ 727 size_t overhead; 728 /* This is the total size of all chunks INCLUDING padding. */ 729 size_t size; 730 /* This is the maximum size this packet may have */ 731 size_t max_size; 732 733 /* The packet is destined for this transport address. 734 * The function we finally use to pass down to the next lower 735 * layer lives in the transport structure. 736 */ 737 struct sctp_transport *transport; 738 739 /* pointer to the auth chunk for this packet */ 740 struct sctp_chunk *auth; 741 742 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */ 743 has_sack:1, /* This packet contains a SACK chunk. */ 744 has_auth:1, /* This packet contains an AUTH chunk */ 745 has_data:1, /* This packet contains at least 1 DATA chunk */ 746 ipfragok:1; /* So let ip fragment this packet */ 747 }; 748 749 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *, 750 __u16 sport, __u16 dport); 751 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int); 752 enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet, 753 struct sctp_chunk *chunk, 754 int one_packet, gfp_t gfp); 755 enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet, 756 struct sctp_chunk *chunk); 757 int sctp_packet_transmit(struct sctp_packet *, gfp_t); 758 void sctp_packet_free(struct sctp_packet *); 759 760 static inline int sctp_packet_empty(struct sctp_packet *packet) 761 { 762 return packet->size == packet->overhead; 763 } 764 765 /* This represents a remote transport address. 766 * For local transport addresses, we just use union sctp_addr. 767 * 768 * RFC2960 Section 1.4 Key Terms 769 * 770 * o Transport address: A Transport Address is traditionally defined 771 * by Network Layer address, Transport Layer protocol and Transport 772 * Layer port number. In the case of SCTP running over IP, a 773 * transport address is defined by the combination of an IP address 774 * and an SCTP port number (where SCTP is the Transport protocol). 775 * 776 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control 777 * 778 * o The sender keeps a separate congestion control parameter set for 779 * each of the destination addresses it can send to (not each 780 * source-destination pair but for each destination). The parameters 781 * should decay if the address is not used for a long enough time 782 * period. 783 * 784 */ 785 struct sctp_transport { 786 /* A list of transports. */ 787 struct list_head transports; 788 struct rhlist_head node; 789 790 /* Reference counting. */ 791 refcount_t refcnt; 792 /* RTO-Pending : A flag used to track if one of the DATA 793 * chunks sent to this address is currently being 794 * used to compute a RTT. If this flag is 0, 795 * the next DATA chunk sent to this destination 796 * should be used to compute a RTT and this flag 797 * should be set. Every time the RTT 798 * calculation completes (i.e. the DATA chunk 799 * is SACK'd) clear this flag. 800 */ 801 __u32 rto_pending:1, 802 803 /* 804 * hb_sent : a flag that signals that we have a pending 805 * heartbeat. 806 */ 807 hb_sent:1, 808 809 /* Is the Path MTU update pending on this tranport */ 810 pmtu_pending:1, 811 812 dst_pending_confirm:1, /* need to confirm neighbour */ 813 814 /* Has this transport moved the ctsn since we last sacked */ 815 sack_generation:1; 816 u32 dst_cookie; 817 818 struct flowi fl; 819 820 /* This is the peer's IP address and port. */ 821 union sctp_addr ipaddr; 822 823 /* These are the functions we call to handle LLP stuff. */ 824 struct sctp_af *af_specific; 825 826 /* Which association do we belong to? */ 827 struct sctp_association *asoc; 828 829 /* RFC2960 830 * 831 * 12.3 Per Transport Address Data 832 * 833 * For each destination transport address in the peer's 834 * address list derived from the INIT or INIT ACK chunk, a 835 * number of data elements needs to be maintained including: 836 */ 837 /* RTO : The current retransmission timeout value. */ 838 unsigned long rto; 839 840 __u32 rtt; /* This is the most recent RTT. */ 841 842 /* RTTVAR : The current RTT variation. */ 843 __u32 rttvar; 844 845 /* SRTT : The current smoothed round trip time. */ 846 __u32 srtt; 847 848 /* 849 * These are the congestion stats. 850 */ 851 /* cwnd : The current congestion window. */ 852 __u32 cwnd; /* This is the actual cwnd. */ 853 854 /* ssthresh : The current slow start threshold value. */ 855 __u32 ssthresh; 856 857 /* partial : The tracking method for increase of cwnd when in 858 * bytes acked : congestion avoidance mode (see Section 6.2.2) 859 */ 860 __u32 partial_bytes_acked; 861 862 /* Data that has been sent, but not acknowledged. */ 863 __u32 flight_size; 864 865 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */ 866 867 /* Destination */ 868 struct dst_entry *dst; 869 /* Source address. */ 870 union sctp_addr saddr; 871 872 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 873 * the destination address every heartbeat interval. 874 */ 875 unsigned long hbinterval; 876 877 /* SACK delay timeout */ 878 unsigned long sackdelay; 879 __u32 sackfreq; 880 881 atomic_t mtu_info; 882 883 /* When was the last time that we heard from this transport? We use 884 * this to pick new active and retran paths. 885 */ 886 ktime_t last_time_heard; 887 888 /* When was the last time that we sent a chunk using this 889 * transport? We use this to check for idle transports 890 */ 891 unsigned long last_time_sent; 892 893 /* Last time(in jiffies) when cwnd is reduced due to the congestion 894 * indication based on ECNE chunk. 895 */ 896 unsigned long last_time_ecne_reduced; 897 898 /* This is the max_retrans value for the transport and will 899 * be initialized from the assocs value. This can be changed 900 * using the SCTP_SET_PEER_ADDR_PARAMS socket option. 901 */ 902 __u16 pathmaxrxt; 903 904 __u32 flowlabel; 905 __u8 dscp; 906 907 /* This is the partially failed retrans value for the transport 908 * and will be initialized from the assocs value. This can be changed 909 * using the SCTP_PEER_ADDR_THLDS socket option 910 */ 911 int pf_retrans; 912 /* PMTU : The current known path MTU. */ 913 __u32 pathmtu; 914 915 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 916 __u32 param_flags; 917 918 /* The number of times INIT has been sent on this transport. */ 919 int init_sent_count; 920 921 /* state : The current state of this destination, 922 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN. 923 */ 924 int state; 925 926 /* These are the error stats for this destination. */ 927 928 /* Error count : The current error count for this destination. */ 929 unsigned short error_count; 930 931 /* Per : A timer used by each destination. 932 * Destination : 933 * Timer : 934 * 935 * [Everywhere else in the text this is called T3-rtx. -ed] 936 */ 937 struct timer_list T3_rtx_timer; 938 939 /* Heartbeat timer is per destination. */ 940 struct timer_list hb_timer; 941 942 /* Timer to handle ICMP proto unreachable envets */ 943 struct timer_list proto_unreach_timer; 944 945 /* Timer to handler reconf chunk rtx */ 946 struct timer_list reconf_timer; 947 948 /* Since we're using per-destination retransmission timers 949 * (see above), we're also using per-destination "transmitted" 950 * queues. This probably ought to be a private struct 951 * accessible only within the outqueue, but it's not, yet. 952 */ 953 struct list_head transmitted; 954 955 /* We build bundle-able packets for this transport here. */ 956 struct sctp_packet packet; 957 958 /* This is the list of transports that have chunks to send. */ 959 struct list_head send_ready; 960 961 /* State information saved for SFR_CACC algorithm. The key 962 * idea in SFR_CACC is to maintain state at the sender on a 963 * per-destination basis when a changeover happens. 964 * char changeover_active; 965 * char cycling_changeover; 966 * __u32 next_tsn_at_change; 967 * char cacc_saw_newack; 968 */ 969 struct { 970 /* An unsigned integer, which stores the next TSN to be 971 * used by the sender, at the moment of changeover. 972 */ 973 __u32 next_tsn_at_change; 974 975 /* A flag which indicates the occurrence of a changeover */ 976 char changeover_active; 977 978 /* A flag which indicates whether the change of primary is 979 * the first switch to this destination address during an 980 * active switch. 981 */ 982 char cycling_changeover; 983 984 /* A temporary flag, which is used during the processing of 985 * a SACK to estimate the causative TSN(s)'s group. 986 */ 987 char cacc_saw_newack; 988 } cacc; 989 990 /* 64-bit random number sent with heartbeat. */ 991 __u64 hb_nonce; 992 993 struct rcu_head rcu; 994 }; 995 996 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *, 997 gfp_t); 998 void sctp_transport_set_owner(struct sctp_transport *, 999 struct sctp_association *); 1000 void sctp_transport_route(struct sctp_transport *, union sctp_addr *, 1001 struct sctp_sock *); 1002 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk); 1003 void sctp_transport_free(struct sctp_transport *); 1004 void sctp_transport_reset_t3_rtx(struct sctp_transport *); 1005 void sctp_transport_reset_hb_timer(struct sctp_transport *); 1006 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport); 1007 int sctp_transport_hold(struct sctp_transport *); 1008 void sctp_transport_put(struct sctp_transport *); 1009 void sctp_transport_update_rto(struct sctp_transport *, __u32); 1010 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32); 1011 void sctp_transport_lower_cwnd(struct sctp_transport *t, 1012 enum sctp_lower_cwnd reason); 1013 void sctp_transport_burst_limited(struct sctp_transport *); 1014 void sctp_transport_burst_reset(struct sctp_transport *); 1015 unsigned long sctp_transport_timeout(struct sctp_transport *); 1016 void sctp_transport_reset(struct sctp_transport *t); 1017 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu); 1018 void sctp_transport_immediate_rtx(struct sctp_transport *); 1019 void sctp_transport_dst_release(struct sctp_transport *t); 1020 void sctp_transport_dst_confirm(struct sctp_transport *t); 1021 1022 1023 /* This is the structure we use to queue packets as they come into 1024 * SCTP. We write packets to it and read chunks from it. 1025 */ 1026 struct sctp_inq { 1027 /* This is actually a queue of sctp_chunk each 1028 * containing a partially decoded packet. 1029 */ 1030 struct list_head in_chunk_list; 1031 /* This is the packet which is currently off the in queue and is 1032 * being worked on through the inbound chunk processing. 1033 */ 1034 struct sctp_chunk *in_progress; 1035 1036 /* This is the delayed task to finish delivering inbound 1037 * messages. 1038 */ 1039 struct work_struct immediate; 1040 }; 1041 1042 void sctp_inq_init(struct sctp_inq *); 1043 void sctp_inq_free(struct sctp_inq *); 1044 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet); 1045 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *); 1046 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *); 1047 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t); 1048 1049 /* This is the structure we use to hold outbound chunks. You push 1050 * chunks in and they automatically pop out the other end as bundled 1051 * packets (it calls (*output_handler)()). 1052 * 1053 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1, 1054 * and 8.2 of the v13 draft. 1055 * 1056 * It handles retransmissions. The connection to the timeout portion 1057 * of the state machine is through sctp_..._timeout() and timeout_handler. 1058 * 1059 * If you feed it SACKs, it will eat them. 1060 * 1061 * If you give it big chunks, it will fragment them. 1062 * 1063 * It assigns TSN's to data chunks. This happens at the last possible 1064 * instant before transmission. 1065 * 1066 * When free()'d, it empties itself out via output_handler(). 1067 */ 1068 struct sctp_outq { 1069 struct sctp_association *asoc; 1070 1071 /* Data pending that has never been transmitted. */ 1072 struct list_head out_chunk_list; 1073 1074 /* Stream scheduler being used */ 1075 struct sctp_sched_ops *sched; 1076 1077 unsigned int out_qlen; /* Total length of queued data chunks. */ 1078 1079 /* Error of send failed, may used in SCTP_SEND_FAILED event. */ 1080 unsigned int error; 1081 1082 /* These are control chunks we want to send. */ 1083 struct list_head control_chunk_list; 1084 1085 /* These are chunks that have been sacked but are above the 1086 * CTSN, or cumulative tsn ack point. 1087 */ 1088 struct list_head sacked; 1089 1090 /* Put chunks on this list to schedule them for 1091 * retransmission. 1092 */ 1093 struct list_head retransmit; 1094 1095 /* Put chunks on this list to save them for FWD TSN processing as 1096 * they were abandoned. 1097 */ 1098 struct list_head abandoned; 1099 1100 /* How many unackd bytes do we have in-flight? */ 1101 __u32 outstanding_bytes; 1102 1103 /* Are we doing fast-rtx on this queue */ 1104 char fast_rtx; 1105 1106 /* Corked? */ 1107 char cork; 1108 }; 1109 1110 void sctp_outq_init(struct sctp_association *, struct sctp_outq *); 1111 void sctp_outq_teardown(struct sctp_outq *); 1112 void sctp_outq_free(struct sctp_outq*); 1113 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t); 1114 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *); 1115 int sctp_outq_is_empty(const struct sctp_outq *); 1116 void sctp_outq_restart(struct sctp_outq *); 1117 1118 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport, 1119 enum sctp_retransmit_reason reason); 1120 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8); 1121 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp); 1122 void sctp_prsctp_prune(struct sctp_association *asoc, 1123 struct sctp_sndrcvinfo *sinfo, int msg_len); 1124 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn); 1125 /* Uncork and flush an outqueue. */ 1126 static inline void sctp_outq_cork(struct sctp_outq *q) 1127 { 1128 q->cork = 1; 1129 } 1130 1131 /* SCTP skb control block. 1132 * sctp_input_cb is currently used on rx and sock rx queue 1133 */ 1134 struct sctp_input_cb { 1135 union { 1136 struct inet_skb_parm h4; 1137 #if IS_ENABLED(CONFIG_IPV6) 1138 struct inet6_skb_parm h6; 1139 #endif 1140 } header; 1141 struct sctp_chunk *chunk; 1142 struct sctp_af *af; 1143 }; 1144 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0])) 1145 1146 struct sctp_output_cb { 1147 struct sk_buff *last; 1148 }; 1149 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0])) 1150 1151 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb) 1152 { 1153 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; 1154 1155 return chunk->head_skb ? : skb; 1156 } 1157 1158 /* These bind address data fields common between endpoints and associations */ 1159 struct sctp_bind_addr { 1160 1161 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1162 * 1163 * SCTP Port: The local SCTP port number the endpoint is 1164 * bound to. 1165 */ 1166 __u16 port; 1167 1168 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1169 * 1170 * Address List: The list of IP addresses that this instance 1171 * has bound. This information is passed to one's 1172 * peer(s) in INIT and INIT ACK chunks. 1173 */ 1174 struct list_head address_list; 1175 }; 1176 1177 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port); 1178 void sctp_bind_addr_free(struct sctp_bind_addr *); 1179 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest, 1180 const struct sctp_bind_addr *src, 1181 enum sctp_scope scope, gfp_t gfp, 1182 int flags); 1183 int sctp_bind_addr_dup(struct sctp_bind_addr *dest, 1184 const struct sctp_bind_addr *src, 1185 gfp_t gfp); 1186 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *, 1187 int new_size, __u8 addr_state, gfp_t gfp); 1188 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *); 1189 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *, 1190 struct sctp_sock *); 1191 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *, 1192 struct sctp_sock *, struct sctp_sock *); 1193 int sctp_bind_addr_state(const struct sctp_bind_addr *bp, 1194 const union sctp_addr *addr); 1195 int sctp_bind_addrs_check(struct sctp_sock *sp, 1196 struct sctp_sock *sp2, int cnt2); 1197 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp, 1198 const union sctp_addr *addrs, 1199 int addrcnt, 1200 struct sctp_sock *opt); 1201 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp, 1202 int *addrs_len, 1203 gfp_t gfp); 1204 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len, 1205 __u16 port, gfp_t gfp); 1206 1207 enum sctp_scope sctp_scope(const union sctp_addr *addr); 1208 int sctp_in_scope(struct net *net, const union sctp_addr *addr, 1209 const enum sctp_scope scope); 1210 int sctp_is_any(struct sock *sk, const union sctp_addr *addr); 1211 int sctp_is_ep_boundall(struct sock *sk); 1212 1213 1214 /* What type of endpoint? */ 1215 enum sctp_endpoint_type { 1216 SCTP_EP_TYPE_SOCKET, 1217 SCTP_EP_TYPE_ASSOCIATION, 1218 }; 1219 1220 /* 1221 * A common base class to bridge the implmentation view of a 1222 * socket (usually listening) endpoint versus an association's 1223 * local endpoint. 1224 * This common structure is useful for several purposes: 1225 * 1) Common interface for lookup routines. 1226 * a) Subfunctions work for either endpoint or association 1227 * b) Single interface to lookup allows hiding the lookup lock rather 1228 * than acquiring it externally. 1229 * 2) Common interface for the inbound chunk handling/state machine. 1230 * 3) Common object handling routines for reference counting, etc. 1231 * 4) Disentangle association lookup from endpoint lookup, where we 1232 * do not have to find our endpoint to find our association. 1233 * 1234 */ 1235 1236 struct sctp_ep_common { 1237 /* Fields to help us manage our entries in the hash tables. */ 1238 struct hlist_node node; 1239 int hashent; 1240 1241 /* Runtime type information. What kind of endpoint is this? */ 1242 enum sctp_endpoint_type type; 1243 1244 /* Some fields to help us manage this object. 1245 * refcnt - Reference count access to this object. 1246 * dead - Do not attempt to use this object. 1247 */ 1248 refcount_t refcnt; 1249 bool dead; 1250 1251 /* What socket does this endpoint belong to? */ 1252 struct sock *sk; 1253 1254 /* This is where we receive inbound chunks. */ 1255 struct sctp_inq inqueue; 1256 1257 /* This substructure includes the defining parameters of the 1258 * endpoint: 1259 * bind_addr.port is our shared port number. 1260 * bind_addr.address_list is our set of local IP addresses. 1261 */ 1262 struct sctp_bind_addr bind_addr; 1263 }; 1264 1265 1266 /* RFC Section 1.4 Key Terms 1267 * 1268 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a 1269 * multi-homed host, an SCTP endpoint is represented to its peers as a 1270 * combination of a set of eligible destination transport addresses to 1271 * which SCTP packets can be sent and a set of eligible source 1272 * transport addresses from which SCTP packets can be received. 1273 * All transport addresses used by an SCTP endpoint must use the 1274 * same port number, but can use multiple IP addresses. A transport 1275 * address used by an SCTP endpoint must not be used by another 1276 * SCTP endpoint. In other words, a transport address is unique 1277 * to an SCTP endpoint. 1278 * 1279 * From an implementation perspective, each socket has one of these. 1280 * A TCP-style socket will have exactly one association on one of 1281 * these. An UDP-style socket will have multiple associations hanging 1282 * off one of these. 1283 */ 1284 1285 struct sctp_endpoint { 1286 /* Common substructure for endpoint and association. */ 1287 struct sctp_ep_common base; 1288 1289 /* Associations: A list of current associations and mappings 1290 * to the data consumers for each association. This 1291 * may be in the form of a hash table or other 1292 * implementation dependent structure. The data 1293 * consumers may be process identification 1294 * information such as file descriptors, named pipe 1295 * pointer, or table pointers dependent on how SCTP 1296 * is implemented. 1297 */ 1298 /* This is really a list of struct sctp_association entries. */ 1299 struct list_head asocs; 1300 1301 /* Secret Key: A secret key used by this endpoint to compute 1302 * the MAC. This SHOULD be a cryptographic quality 1303 * random number with a sufficient length. 1304 * Discussion in [RFC1750] can be helpful in 1305 * selection of the key. 1306 */ 1307 __u8 secret_key[SCTP_SECRET_SIZE]; 1308 1309 /* digest: This is a digest of the sctp cookie. This field is 1310 * only used on the receive path when we try to validate 1311 * that the cookie has not been tampered with. We put 1312 * this here so we pre-allocate this once and can re-use 1313 * on every receive. 1314 */ 1315 __u8 *digest; 1316 1317 /* sendbuf acct. policy. */ 1318 __u32 sndbuf_policy; 1319 1320 /* rcvbuf acct. policy. */ 1321 __u32 rcvbuf_policy; 1322 1323 /* SCTP AUTH: array of the HMACs that will be allocated 1324 * we need this per association so that we don't serialize 1325 */ 1326 struct crypto_shash **auth_hmacs; 1327 1328 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */ 1329 struct sctp_hmac_algo_param *auth_hmacs_list; 1330 1331 /* SCTP-AUTH: chunks to authenticate encoded into parameter */ 1332 struct sctp_chunks_param *auth_chunk_list; 1333 1334 /* SCTP-AUTH: endpoint shared keys */ 1335 struct list_head endpoint_shared_keys; 1336 __u16 active_key_id; 1337 __u8 auth_enable:1, 1338 prsctp_enable:1, 1339 reconf_enable:1; 1340 1341 __u8 strreset_enable; 1342 1343 /* Security identifiers from incoming (INIT). These are set by 1344 * security_sctp_assoc_request(). These will only be used by 1345 * SCTP TCP type sockets and peeled off connections as they 1346 * cause a new socket to be generated. security_sctp_sk_clone() 1347 * will then plug these into the new socket. 1348 */ 1349 1350 u32 secid; 1351 u32 peer_secid; 1352 }; 1353 1354 /* Recover the outter endpoint structure. */ 1355 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base) 1356 { 1357 struct sctp_endpoint *ep; 1358 1359 ep = container_of(base, struct sctp_endpoint, base); 1360 return ep; 1361 } 1362 1363 /* These are function signatures for manipulating endpoints. */ 1364 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t); 1365 void sctp_endpoint_free(struct sctp_endpoint *); 1366 void sctp_endpoint_put(struct sctp_endpoint *); 1367 void sctp_endpoint_hold(struct sctp_endpoint *); 1368 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *); 1369 struct sctp_association *sctp_endpoint_lookup_assoc( 1370 const struct sctp_endpoint *ep, 1371 const union sctp_addr *paddr, 1372 struct sctp_transport **); 1373 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep, 1374 const union sctp_addr *paddr); 1375 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *, 1376 struct net *, const union sctp_addr *); 1377 bool sctp_has_association(struct net *net, const union sctp_addr *laddr, 1378 const union sctp_addr *paddr); 1379 1380 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep, 1381 const struct sctp_association *asoc, 1382 enum sctp_cid cid, struct sctp_init_chunk *peer_init, 1383 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk); 1384 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk, 1385 const union sctp_addr *peer, 1386 struct sctp_init_chunk *init, gfp_t gfp); 1387 __u32 sctp_generate_tag(const struct sctp_endpoint *); 1388 __u32 sctp_generate_tsn(const struct sctp_endpoint *); 1389 1390 struct sctp_inithdr_host { 1391 __u32 init_tag; 1392 __u32 a_rwnd; 1393 __u16 num_outbound_streams; 1394 __u16 num_inbound_streams; 1395 __u32 initial_tsn; 1396 }; 1397 1398 struct sctp_stream_priorities { 1399 /* List of priorities scheduled */ 1400 struct list_head prio_sched; 1401 /* List of streams scheduled */ 1402 struct list_head active; 1403 /* The next stream stream in line */ 1404 struct sctp_stream_out_ext *next; 1405 __u16 prio; 1406 }; 1407 1408 struct sctp_stream_out_ext { 1409 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 1410 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 1411 struct list_head outq; /* chunks enqueued by this stream */ 1412 union { 1413 struct { 1414 /* Scheduled streams list */ 1415 struct list_head prio_list; 1416 struct sctp_stream_priorities *prio_head; 1417 }; 1418 /* Fields used by RR scheduler */ 1419 struct { 1420 struct list_head rr_list; 1421 }; 1422 }; 1423 }; 1424 1425 struct sctp_stream_out { 1426 union { 1427 __u32 mid; 1428 __u16 ssn; 1429 }; 1430 __u32 mid_uo; 1431 struct sctp_stream_out_ext *ext; 1432 __u8 state; 1433 }; 1434 1435 struct sctp_stream_in { 1436 union { 1437 __u32 mid; 1438 __u16 ssn; 1439 }; 1440 __u32 mid_uo; 1441 __u32 fsn; 1442 __u32 fsn_uo; 1443 char pd_mode; 1444 char pd_mode_uo; 1445 }; 1446 1447 struct sctp_stream { 1448 struct flex_array *out; 1449 struct flex_array *in; 1450 __u16 outcnt; 1451 __u16 incnt; 1452 /* Current stream being sent, if any */ 1453 struct sctp_stream_out *out_curr; 1454 union { 1455 /* Fields used by priority scheduler */ 1456 struct { 1457 /* List of priorities scheduled */ 1458 struct list_head prio_list; 1459 }; 1460 /* Fields used by RR scheduler */ 1461 struct { 1462 /* List of streams scheduled */ 1463 struct list_head rr_list; 1464 /* The next stream stream in line */ 1465 struct sctp_stream_out_ext *rr_next; 1466 }; 1467 }; 1468 struct sctp_stream_interleave *si; 1469 }; 1470 1471 static inline struct sctp_stream_out *sctp_stream_out( 1472 const struct sctp_stream *stream, 1473 __u16 sid) 1474 { 1475 return flex_array_get(stream->out, sid); 1476 } 1477 1478 static inline struct sctp_stream_in *sctp_stream_in( 1479 const struct sctp_stream *stream, 1480 __u16 sid) 1481 { 1482 return flex_array_get(stream->in, sid); 1483 } 1484 1485 #define SCTP_SO(s, i) sctp_stream_out((s), (i)) 1486 #define SCTP_SI(s, i) sctp_stream_in((s), (i)) 1487 1488 #define SCTP_STREAM_CLOSED 0x00 1489 #define SCTP_STREAM_OPEN 0x01 1490 1491 static inline __u16 sctp_datachk_len(const struct sctp_stream *stream) 1492 { 1493 return stream->si->data_chunk_len; 1494 } 1495 1496 static inline __u16 sctp_datahdr_len(const struct sctp_stream *stream) 1497 { 1498 return stream->si->data_chunk_len - sizeof(struct sctp_chunkhdr); 1499 } 1500 1501 static inline __u16 sctp_ftsnchk_len(const struct sctp_stream *stream) 1502 { 1503 return stream->si->ftsn_chunk_len; 1504 } 1505 1506 static inline __u16 sctp_ftsnhdr_len(const struct sctp_stream *stream) 1507 { 1508 return stream->si->ftsn_chunk_len - sizeof(struct sctp_chunkhdr); 1509 } 1510 1511 /* SCTP_GET_ASSOC_STATS counters */ 1512 struct sctp_priv_assoc_stats { 1513 /* Maximum observed rto in the association during subsequent 1514 * observations. Value is set to 0 if no RTO measurement took place 1515 * The transport where the max_rto was observed is returned in 1516 * obs_rto_ipaddr 1517 */ 1518 struct sockaddr_storage obs_rto_ipaddr; 1519 __u64 max_obs_rto; 1520 /* Total In and Out SACKs received and sent */ 1521 __u64 isacks; 1522 __u64 osacks; 1523 /* Total In and Out packets received and sent */ 1524 __u64 opackets; 1525 __u64 ipackets; 1526 /* Total retransmitted chunks */ 1527 __u64 rtxchunks; 1528 /* TSN received > next expected */ 1529 __u64 outofseqtsns; 1530 /* Duplicate Chunks received */ 1531 __u64 idupchunks; 1532 /* Gap Ack Blocks received */ 1533 __u64 gapcnt; 1534 /* Unordered data chunks sent and received */ 1535 __u64 ouodchunks; 1536 __u64 iuodchunks; 1537 /* Ordered data chunks sent and received */ 1538 __u64 oodchunks; 1539 __u64 iodchunks; 1540 /* Control chunks sent and received */ 1541 __u64 octrlchunks; 1542 __u64 ictrlchunks; 1543 }; 1544 1545 /* RFC2960 1546 * 1547 * 12. Recommended Transmission Control Block (TCB) Parameters 1548 * 1549 * This section details a recommended set of parameters that should 1550 * be contained within the TCB for an implementation. This section is 1551 * for illustrative purposes and should not be deemed as requirements 1552 * on an implementation or as an exhaustive list of all parameters 1553 * inside an SCTP TCB. Each implementation may need its own additional 1554 * parameters for optimization. 1555 */ 1556 1557 1558 /* Here we have information about each individual association. */ 1559 struct sctp_association { 1560 1561 /* A base structure common to endpoint and association. 1562 * In this context, it represents the associations's view 1563 * of the local endpoint of the association. 1564 */ 1565 struct sctp_ep_common base; 1566 1567 /* Associations on the same socket. */ 1568 struct list_head asocs; 1569 1570 /* association id. */ 1571 sctp_assoc_t assoc_id; 1572 1573 /* This is our parent endpoint. */ 1574 struct sctp_endpoint *ep; 1575 1576 /* These are those association elements needed in the cookie. */ 1577 struct sctp_cookie c; 1578 1579 /* This is all information about our peer. */ 1580 struct { 1581 /* transport_addr_list 1582 * 1583 * Peer : A list of SCTP transport addresses that the 1584 * Transport : peer is bound to. This information is derived 1585 * Address : from the INIT or INIT ACK and is used to 1586 * List : associate an inbound packet with a given 1587 * : association. Normally this information is 1588 * : hashed or keyed for quick lookup and access 1589 * : of the TCB. 1590 * : The list is also initialized with the list 1591 * : of addresses passed with the sctp_connectx() 1592 * : call. 1593 * 1594 * It is a list of SCTP_transport's. 1595 */ 1596 struct list_head transport_addr_list; 1597 1598 /* rwnd 1599 * 1600 * Peer Rwnd : Current calculated value of the peer's rwnd. 1601 */ 1602 __u32 rwnd; 1603 1604 /* transport_count 1605 * 1606 * Peer : A count of the number of peer addresses 1607 * Transport : in the Peer Transport Address List. 1608 * Address : 1609 * Count : 1610 */ 1611 __u16 transport_count; 1612 1613 /* port 1614 * The transport layer port number. 1615 */ 1616 __u16 port; 1617 1618 /* primary_path 1619 * 1620 * Primary : This is the current primary destination 1621 * Path : transport address of the peer endpoint. It 1622 * : may also specify a source transport address 1623 * : on this endpoint. 1624 * 1625 * All of these paths live on transport_addr_list. 1626 * 1627 * At the bakeoffs, we discovered that the intent of 1628 * primaryPath is that it only changes when the ULP 1629 * asks to have it changed. We add the activePath to 1630 * designate the connection we are currently using to 1631 * transmit new data and most control chunks. 1632 */ 1633 struct sctp_transport *primary_path; 1634 1635 /* Cache the primary path address here, when we 1636 * need a an address for msg_name. 1637 */ 1638 union sctp_addr primary_addr; 1639 1640 /* active_path 1641 * The path that we are currently using to 1642 * transmit new data and most control chunks. 1643 */ 1644 struct sctp_transport *active_path; 1645 1646 /* retran_path 1647 * 1648 * RFC2960 6.4 Multi-homed SCTP Endpoints 1649 * ... 1650 * Furthermore, when its peer is multi-homed, an 1651 * endpoint SHOULD try to retransmit a chunk to an 1652 * active destination transport address that is 1653 * different from the last destination address to 1654 * which the DATA chunk was sent. 1655 */ 1656 struct sctp_transport *retran_path; 1657 1658 /* Pointer to last transport I have sent on. */ 1659 struct sctp_transport *last_sent_to; 1660 1661 /* This is the last transport I have received DATA on. */ 1662 struct sctp_transport *last_data_from; 1663 1664 /* 1665 * Mapping An array of bits or bytes indicating which out of 1666 * Array order TSN's have been received (relative to the 1667 * Last Rcvd TSN). If no gaps exist, i.e. no out of 1668 * order packets have been received, this array 1669 * will be set to all zero. This structure may be 1670 * in the form of a circular buffer or bit array. 1671 * 1672 * Last Rcvd : This is the last TSN received in 1673 * TSN : sequence. This value is set initially by 1674 * : taking the peer's Initial TSN, received in 1675 * : the INIT or INIT ACK chunk, and subtracting 1676 * : one from it. 1677 * 1678 * Throughout most of the specification this is called the 1679 * "Cumulative TSN ACK Point". In this case, we 1680 * ignore the advice in 12.2 in favour of the term 1681 * used in the bulk of the text. This value is hidden 1682 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn(). 1683 */ 1684 struct sctp_tsnmap tsn_map; 1685 1686 /* This mask is used to disable sending the ASCONF chunk 1687 * with specified parameter to peer. 1688 */ 1689 __be16 addip_disabled_mask; 1690 1691 /* These are capabilities which our peer advertised. */ 1692 __u8 ecn_capable:1, /* Can peer do ECN? */ 1693 ipv4_address:1, /* Peer understands IPv4 addresses? */ 1694 ipv6_address:1, /* Peer understands IPv6 addresses? */ 1695 hostname_address:1, /* Peer understands DNS addresses? */ 1696 asconf_capable:1, /* Does peer support ADDIP? */ 1697 prsctp_capable:1, /* Can peer do PR-SCTP? */ 1698 reconf_capable:1, /* Can peer do RE-CONFIG? */ 1699 auth_capable:1; /* Is peer doing SCTP-AUTH? */ 1700 1701 /* sack_needed : This flag indicates if the next received 1702 * : packet is to be responded to with a 1703 * : SACK. This is initialized to 0. When a packet 1704 * : is received sack_cnt is incremented. If this value 1705 * : reaches 2 or more, a SACK is sent and the 1706 * : value is reset to 0. Note: This is used only 1707 * : when no DATA chunks are received out of 1708 * : order. When DATA chunks are out of order, 1709 * : SACK's are not delayed (see Section 6). 1710 */ 1711 __u8 sack_needed:1, /* Do we need to sack the peer? */ 1712 sack_generation:1, 1713 zero_window_announced:1; 1714 __u32 sack_cnt; 1715 1716 __u32 adaptation_ind; /* Adaptation Code point. */ 1717 1718 struct sctp_inithdr_host i; 1719 void *cookie; 1720 int cookie_len; 1721 1722 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. 1723 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the 1724 * Initial TSN Value minus 1 1725 */ 1726 __u32 addip_serial; 1727 1728 /* SCTP-AUTH: We need to know pears random number, hmac list 1729 * and authenticated chunk list. All that is part of the 1730 * cookie and these are just pointers to those locations 1731 */ 1732 struct sctp_random_param *peer_random; 1733 struct sctp_chunks_param *peer_chunks; 1734 struct sctp_hmac_algo_param *peer_hmacs; 1735 } peer; 1736 1737 /* State : A state variable indicating what state the 1738 * : association is in, i.e. COOKIE-WAIT, 1739 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING, 1740 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT. 1741 * 1742 * Note: No "CLOSED" state is illustrated since if a 1743 * association is "CLOSED" its TCB SHOULD be removed. 1744 * 1745 * In this implementation we DO have a CLOSED 1746 * state which is used during initiation and shutdown. 1747 * 1748 * State takes values from SCTP_STATE_*. 1749 */ 1750 enum sctp_state state; 1751 1752 /* Overall : The overall association error count. 1753 * Error Count : [Clear this any time I get something.] 1754 */ 1755 int overall_error_count; 1756 1757 /* The cookie life I award for any cookie. */ 1758 ktime_t cookie_life; 1759 1760 /* These are the association's initial, max, and min RTO values. 1761 * These values will be initialized by system defaults, but can 1762 * be modified via the SCTP_RTOINFO socket option. 1763 */ 1764 unsigned long rto_initial; 1765 unsigned long rto_max; 1766 unsigned long rto_min; 1767 1768 /* Maximum number of new data packets that can be sent in a burst. */ 1769 int max_burst; 1770 1771 /* This is the max_retrans value for the association. This value will 1772 * be initialized initialized from system defaults, but can be 1773 * modified by the SCTP_ASSOCINFO socket option. 1774 */ 1775 int max_retrans; 1776 1777 /* This is the partially failed retrans value for the transport 1778 * and will be initialized from the assocs value. This can be 1779 * changed using the SCTP_PEER_ADDR_THLDS socket option 1780 */ 1781 int pf_retrans; 1782 1783 /* Maximum number of times the endpoint will retransmit INIT */ 1784 __u16 max_init_attempts; 1785 1786 /* How many times have we resent an INIT? */ 1787 __u16 init_retries; 1788 1789 /* The largest timeout or RTO value to use in attempting an INIT */ 1790 unsigned long max_init_timeo; 1791 1792 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 1793 * the destination address every heartbeat interval. This value 1794 * will be inherited by all new transports. 1795 */ 1796 unsigned long hbinterval; 1797 1798 /* This is the max_retrans value for new transports in the 1799 * association. 1800 */ 1801 __u16 pathmaxrxt; 1802 1803 __u32 flowlabel; 1804 __u8 dscp; 1805 1806 /* Flag that path mtu update is pending */ 1807 __u8 pmtu_pending; 1808 1809 /* Association : The smallest PMTU discovered for all of the 1810 * PMTU : peer's transport addresses. 1811 */ 1812 __u32 pathmtu; 1813 1814 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 1815 __u32 param_flags; 1816 1817 __u32 sackfreq; 1818 /* SACK delay timeout */ 1819 unsigned long sackdelay; 1820 1821 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES]; 1822 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES]; 1823 1824 /* Transport to which SHUTDOWN chunk was last sent. */ 1825 struct sctp_transport *shutdown_last_sent_to; 1826 1827 /* Transport to which INIT chunk was last sent. */ 1828 struct sctp_transport *init_last_sent_to; 1829 1830 /* How many times have we resent a SHUTDOWN */ 1831 int shutdown_retries; 1832 1833 /* Next TSN : The next TSN number to be assigned to a new 1834 * : DATA chunk. This is sent in the INIT or INIT 1835 * : ACK chunk to the peer and incremented each 1836 * : time a DATA chunk is assigned a TSN 1837 * : (normally just prior to transmit or during 1838 * : fragmentation). 1839 */ 1840 __u32 next_tsn; 1841 1842 /* 1843 * Last Rcvd : This is the last TSN received in sequence. This value 1844 * TSN : is set initially by taking the peer's Initial TSN, 1845 * : received in the INIT or INIT ACK chunk, and 1846 * : subtracting one from it. 1847 * 1848 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point. 1849 */ 1850 1851 __u32 ctsn_ack_point; 1852 1853 /* PR-SCTP Advanced.Peer.Ack.Point */ 1854 __u32 adv_peer_ack_point; 1855 1856 /* Highest TSN that is acknowledged by incoming SACKs. */ 1857 __u32 highest_sacked; 1858 1859 /* TSN marking the fast recovery exit point */ 1860 __u32 fast_recovery_exit; 1861 1862 /* Flag to track the current fast recovery state */ 1863 __u8 fast_recovery; 1864 1865 /* The number of unacknowledged data chunks. Reported through 1866 * the SCTP_STATUS sockopt. 1867 */ 1868 __u16 unack_data; 1869 1870 /* The total number of data chunks that we've had to retransmit 1871 * as the result of a T3 timer expiration 1872 */ 1873 __u32 rtx_data_chunks; 1874 1875 /* This is the association's receive buffer space. This value is used 1876 * to set a_rwnd field in an INIT or a SACK chunk. 1877 */ 1878 __u32 rwnd; 1879 1880 /* This is the last advertised value of rwnd over a SACK chunk. */ 1881 __u32 a_rwnd; 1882 1883 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed 1884 * to slop over a maximum of the association's frag_point. 1885 */ 1886 __u32 rwnd_over; 1887 1888 /* Keeps treack of rwnd pressure. This happens when we have 1889 * a window, but not recevie buffer (i.e small packets). This one 1890 * is releases slowly (1 PMTU at a time ). 1891 */ 1892 __u32 rwnd_press; 1893 1894 /* This is the sndbuf size in use for the association. 1895 * This corresponds to the sndbuf size for the association, 1896 * as specified in the sk->sndbuf. 1897 */ 1898 int sndbuf_used; 1899 1900 /* This is the amount of memory that this association has allocated 1901 * in the receive path at any given time. 1902 */ 1903 atomic_t rmem_alloc; 1904 1905 /* This is the wait queue head for send requests waiting on 1906 * the association sndbuf space. 1907 */ 1908 wait_queue_head_t wait; 1909 1910 /* The message size at which SCTP fragmentation will occur. */ 1911 __u32 frag_point; 1912 __u32 user_frag; 1913 1914 /* Counter used to count INIT errors. */ 1915 int init_err_counter; 1916 1917 /* Count the number of INIT cycles (for doubling timeout). */ 1918 int init_cycle; 1919 1920 /* Default send parameters. */ 1921 __u16 default_stream; 1922 __u16 default_flags; 1923 __u32 default_ppid; 1924 __u32 default_context; 1925 __u32 default_timetolive; 1926 1927 /* Default receive parameters */ 1928 __u32 default_rcv_context; 1929 1930 /* Stream arrays */ 1931 struct sctp_stream stream; 1932 1933 /* All outbound chunks go through this structure. */ 1934 struct sctp_outq outqueue; 1935 1936 /* A smart pipe that will handle reordering and fragmentation, 1937 * as well as handle passing events up to the ULP. 1938 */ 1939 struct sctp_ulpq ulpq; 1940 1941 /* Last TSN that caused an ECNE Chunk to be sent. */ 1942 __u32 last_ecne_tsn; 1943 1944 /* Last TSN that caused a CWR Chunk to be sent. */ 1945 __u32 last_cwr_tsn; 1946 1947 /* How many duplicated TSNs have we seen? */ 1948 int numduptsns; 1949 1950 /* These are to support 1951 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses 1952 * and Enforcement of Flow and Message Limits" 1953 * <draft-ietf-tsvwg-addip-sctp-02.txt> 1954 * or "ADDIP" for short. 1955 */ 1956 1957 1958 1959 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1960 * 1961 * R1) One and only one ASCONF Chunk MAY be in transit and 1962 * unacknowledged at any one time. If a sender, after sending 1963 * an ASCONF chunk, decides it needs to transfer another 1964 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1965 * returns from the previous ASCONF Chunk before sending a 1966 * subsequent ASCONF. Note this restriction binds each side, 1967 * so at any time two ASCONF may be in-transit on any given 1968 * association (one sent from each endpoint). 1969 * 1970 * [This is our one-and-only-one ASCONF in flight. If we do 1971 * not have an ASCONF in flight, this is NULL.] 1972 */ 1973 struct sctp_chunk *addip_last_asconf; 1974 1975 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk. 1976 * 1977 * This is needed to implement itmes E1 - E4 of the updated 1978 * spec. Here is the justification: 1979 * 1980 * Since the peer may bundle multiple ASCONF chunks toward us, 1981 * we now need the ability to cache multiple ACKs. The section 1982 * describes in detail how they are cached and cleaned up. 1983 */ 1984 struct list_head asconf_ack_list; 1985 1986 /* These ASCONF chunks are waiting to be sent. 1987 * 1988 * These chunaks can't be pushed to outqueue until receiving 1989 * ASCONF_ACK for the previous ASCONF indicated by 1990 * addip_last_asconf, so as to guarantee that only one ASCONF 1991 * is in flight at any time. 1992 * 1993 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1994 * 1995 * In defining the ASCONF Chunk transfer procedures, it is 1996 * essential that these transfers MUST NOT cause congestion 1997 * within the network. To achieve this, we place these 1998 * restrictions on the transfer of ASCONF Chunks: 1999 * 2000 * R1) One and only one ASCONF Chunk MAY be in transit and 2001 * unacknowledged at any one time. If a sender, after sending 2002 * an ASCONF chunk, decides it needs to transfer another 2003 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 2004 * returns from the previous ASCONF Chunk before sending a 2005 * subsequent ASCONF. Note this restriction binds each side, 2006 * so at any time two ASCONF may be in-transit on any given 2007 * association (one sent from each endpoint). 2008 * 2009 * 2010 * [I really think this is EXACTLY the sort of intelligence 2011 * which already resides in sctp_outq. Please move this 2012 * queue and its supporting logic down there. --piggy] 2013 */ 2014 struct list_head addip_chunk_list; 2015 2016 /* ADDIP Section 4.1 ASCONF Chunk Procedures 2017 * 2018 * A2) A serial number should be assigned to the Chunk. The 2019 * serial number SHOULD be a monotonically increasing 2020 * number. The serial number SHOULD be initialized at 2021 * the start of the association to the same value as the 2022 * Initial TSN and every time a new ASCONF chunk is created 2023 * it is incremented by one after assigning the serial number 2024 * to the newly created chunk. 2025 * 2026 * ADDIP 2027 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF) 2028 * 2029 * Serial Number : 32 bits (unsigned integer) 2030 * 2031 * This value represents a Serial Number for the ASCONF 2032 * Chunk. The valid range of Serial Number is from 0 to 2033 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0 2034 * after reaching 4294967295. 2035 */ 2036 __u32 addip_serial; 2037 int src_out_of_asoc_ok; 2038 union sctp_addr *asconf_addr_del_pending; 2039 struct sctp_transport *new_transport; 2040 2041 /* SCTP AUTH: list of the endpoint shared keys. These 2042 * keys are provided out of band by the user applicaton 2043 * and can't change during the lifetime of the association 2044 */ 2045 struct list_head endpoint_shared_keys; 2046 2047 /* SCTP AUTH: 2048 * The current generated assocaition shared key (secret) 2049 */ 2050 struct sctp_auth_bytes *asoc_shared_key; 2051 struct sctp_shared_key *shkey; 2052 2053 /* SCTP AUTH: hmac id of the first peer requested algorithm 2054 * that we support. 2055 */ 2056 __u16 default_hmac_id; 2057 2058 __u16 active_key_id; 2059 2060 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */ 2061 temp:1, /* Is it a temporary association? */ 2062 force_delay:1, 2063 intl_enable:1, 2064 prsctp_enable:1, 2065 reconf_enable:1; 2066 2067 __u8 strreset_enable; 2068 __u8 strreset_outstanding; /* request param count on the fly */ 2069 2070 __u32 strreset_outseq; /* Update after receiving response */ 2071 __u32 strreset_inseq; /* Update after receiving request */ 2072 __u32 strreset_result[2]; /* save the results of last 2 responses */ 2073 2074 struct sctp_chunk *strreset_chunk; /* save request chunk */ 2075 2076 struct sctp_priv_assoc_stats stats; 2077 2078 int sent_cnt_removable; 2079 2080 __u16 subscribe; 2081 2082 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 2083 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 2084 2085 struct rcu_head rcu; 2086 }; 2087 2088 2089 /* An eyecatcher for determining if we are really looking at an 2090 * association data structure. 2091 */ 2092 enum { 2093 SCTP_ASSOC_EYECATCHER = 0xa550c123, 2094 }; 2095 2096 /* Recover the outter association structure. */ 2097 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base) 2098 { 2099 struct sctp_association *asoc; 2100 2101 asoc = container_of(base, struct sctp_association, base); 2102 return asoc; 2103 } 2104 2105 /* These are function signatures for manipulating associations. */ 2106 2107 2108 struct sctp_association * 2109 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk, 2110 enum sctp_scope scope, gfp_t gfp); 2111 void sctp_association_free(struct sctp_association *); 2112 void sctp_association_put(struct sctp_association *); 2113 void sctp_association_hold(struct sctp_association *); 2114 2115 struct sctp_transport *sctp_assoc_choose_alter_transport( 2116 struct sctp_association *, struct sctp_transport *); 2117 void sctp_assoc_update_retran_path(struct sctp_association *); 2118 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *, 2119 const union sctp_addr *); 2120 int sctp_assoc_lookup_laddr(struct sctp_association *asoc, 2121 const union sctp_addr *laddr); 2122 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *, 2123 const union sctp_addr *address, 2124 const gfp_t gfp, 2125 const int peer_state); 2126 void sctp_assoc_del_peer(struct sctp_association *asoc, 2127 const union sctp_addr *addr); 2128 void sctp_assoc_rm_peer(struct sctp_association *asoc, 2129 struct sctp_transport *peer); 2130 void sctp_assoc_control_transport(struct sctp_association *asoc, 2131 struct sctp_transport *transport, 2132 enum sctp_transport_cmd command, 2133 sctp_sn_error_t error); 2134 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32); 2135 void sctp_assoc_migrate(struct sctp_association *, struct sock *); 2136 int sctp_assoc_update(struct sctp_association *old, 2137 struct sctp_association *new); 2138 2139 __u32 sctp_association_get_next_tsn(struct sctp_association *); 2140 2141 void sctp_assoc_update_frag_point(struct sctp_association *asoc); 2142 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu); 2143 void sctp_assoc_sync_pmtu(struct sctp_association *asoc); 2144 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int); 2145 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int); 2146 void sctp_assoc_set_primary(struct sctp_association *, 2147 struct sctp_transport *); 2148 void sctp_assoc_del_nonprimary_peers(struct sctp_association *, 2149 struct sctp_transport *); 2150 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, 2151 enum sctp_scope scope, gfp_t gfp); 2152 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *, 2153 struct sctp_cookie*, 2154 gfp_t gfp); 2155 int sctp_assoc_set_id(struct sctp_association *, gfp_t); 2156 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc); 2157 struct sctp_chunk *sctp_assoc_lookup_asconf_ack( 2158 const struct sctp_association *asoc, 2159 __be32 serial); 2160 void sctp_asconf_queue_teardown(struct sctp_association *asoc); 2161 2162 int sctp_cmp_addr_exact(const union sctp_addr *ss1, 2163 const union sctp_addr *ss2); 2164 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc); 2165 2166 /* A convenience structure to parse out SCTP specific CMSGs. */ 2167 struct sctp_cmsgs { 2168 struct sctp_initmsg *init; 2169 struct sctp_sndrcvinfo *srinfo; 2170 struct sctp_sndinfo *sinfo; 2171 struct sctp_prinfo *prinfo; 2172 struct sctp_authinfo *authinfo; 2173 struct msghdr *addrs_msg; 2174 }; 2175 2176 /* Structure for tracking memory objects */ 2177 struct sctp_dbg_objcnt_entry { 2178 char *label; 2179 atomic_t *counter; 2180 }; 2181 2182 #endif /* __sctp_structs_h__ */ 2183