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