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