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/generic-radix-tree.h> 52 #include <linux/rhashtable-types.h> 53 #include <linux/socket.h> /* linux/in.h needs this!! */ 54 #include <linux/in.h> /* We get struct sockaddr_in. */ 55 #include <linux/in6.h> /* We get struct in6_addr */ 56 #include <linux/ipv6.h> 57 #include <asm/param.h> /* We get MAXHOSTNAMELEN. */ 58 #include <linux/atomic.h> /* This gets us atomic counters. */ 59 #include <linux/skbuff.h> /* We need sk_buff_head. */ 60 #include <linux/workqueue.h> /* We need tq_struct. */ 61 #include <linux/sctp.h> /* We need sctp* header structs. */ 62 #include <net/sctp/auth.h> /* We need auth specific structs */ 63 #include <net/ip.h> /* For inet_skb_parm */ 64 65 /* A convenience structure for handling sockaddr structures. 66 * We should wean ourselves off this. 67 */ 68 union sctp_addr { 69 struct sockaddr_in v4; 70 struct sockaddr_in6 v6; 71 struct sockaddr sa; 72 }; 73 74 /* Forward declarations for data structures. */ 75 struct sctp_globals; 76 struct sctp_endpoint; 77 struct sctp_association; 78 struct sctp_transport; 79 struct sctp_packet; 80 struct sctp_chunk; 81 struct sctp_inq; 82 struct sctp_outq; 83 struct sctp_bind_addr; 84 struct sctp_ulpq; 85 struct sctp_ep_common; 86 struct crypto_shash; 87 struct sctp_stream; 88 89 90 #include <net/sctp/tsnmap.h> 91 #include <net/sctp/ulpevent.h> 92 #include <net/sctp/ulpqueue.h> 93 #include <net/sctp/stream_interleave.h> 94 95 /* Structures useful for managing bind/connect. */ 96 97 struct sctp_bind_bucket { 98 unsigned short port; 99 signed char fastreuse; 100 signed char fastreuseport; 101 kuid_t fastuid; 102 struct hlist_node node; 103 struct hlist_head owner; 104 struct net *net; 105 }; 106 107 struct sctp_bind_hashbucket { 108 spinlock_t lock; 109 struct hlist_head chain; 110 }; 111 112 /* Used for hashing all associations. */ 113 struct sctp_hashbucket { 114 rwlock_t lock; 115 struct hlist_head chain; 116 } __attribute__((__aligned__(8))); 117 118 119 /* The SCTP globals structure. */ 120 extern struct sctp_globals { 121 /* This is a list of groups of functions for each address 122 * family that we support. 123 */ 124 struct list_head address_families; 125 126 /* This is the hash of all endpoints. */ 127 struct sctp_hashbucket *ep_hashtable; 128 /* This is the sctp port control hash. */ 129 struct sctp_bind_hashbucket *port_hashtable; 130 /* This is the hash of all transports. */ 131 struct rhltable transport_hashtable; 132 133 /* Sizes of above hashtables. */ 134 int ep_hashsize; 135 int port_hashsize; 136 137 /* Default initialization values to be applied to new associations. */ 138 __u16 max_instreams; 139 __u16 max_outstreams; 140 141 /* Flag to indicate whether computing and verifying checksum 142 * is disabled. */ 143 bool checksum_disable; 144 } sctp_globals; 145 146 #define sctp_max_instreams (sctp_globals.max_instreams) 147 #define sctp_max_outstreams (sctp_globals.max_outstreams) 148 #define sctp_address_families (sctp_globals.address_families) 149 #define sctp_ep_hashsize (sctp_globals.ep_hashsize) 150 #define sctp_ep_hashtable (sctp_globals.ep_hashtable) 151 #define sctp_port_hashsize (sctp_globals.port_hashsize) 152 #define sctp_port_hashtable (sctp_globals.port_hashtable) 153 #define sctp_transport_hashtable (sctp_globals.transport_hashtable) 154 #define sctp_checksum_disable (sctp_globals.checksum_disable) 155 156 /* SCTP Socket type: UDP or TCP style. */ 157 enum sctp_socket_type { 158 SCTP_SOCKET_UDP = 0, 159 SCTP_SOCKET_UDP_HIGH_BANDWIDTH, 160 SCTP_SOCKET_TCP 161 }; 162 163 /* Per socket SCTP information. */ 164 struct sctp_sock { 165 /* inet_sock has to be the first member of sctp_sock */ 166 struct inet_sock inet; 167 /* What kind of a socket is this? */ 168 enum sctp_socket_type type; 169 170 /* PF_ family specific functions. */ 171 struct sctp_pf *pf; 172 173 /* Access to HMAC transform. */ 174 struct crypto_shash *hmac; 175 char *sctp_hmac_alg; 176 177 /* What is our base endpointer? */ 178 struct sctp_endpoint *ep; 179 180 struct sctp_bind_bucket *bind_hash; 181 /* Various Socket Options. */ 182 __u16 default_stream; 183 __u32 default_ppid; 184 __u16 default_flags; 185 __u32 default_context; 186 __u32 default_timetolive; 187 __u32 default_rcv_context; 188 int max_burst; 189 190 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 191 * the destination address every heartbeat interval. This value 192 * will be inherited by all new associations. 193 */ 194 __u32 hbinterval; 195 196 /* This is the max_retrans value for new associations. */ 197 __u16 pathmaxrxt; 198 199 __u32 flowlabel; 200 __u8 dscp; 201 202 int pf_retrans; 203 204 /* The initial Path MTU to use for new associations. */ 205 __u32 pathmtu; 206 207 /* The default SACK delay timeout for new associations. */ 208 __u32 sackdelay; 209 __u32 sackfreq; 210 211 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 212 __u32 param_flags; 213 214 __u32 default_ss; 215 216 struct sctp_rtoinfo rtoinfo; 217 struct sctp_paddrparams paddrparam; 218 struct sctp_assocparams assocparams; 219 220 /* 221 * These two structures must be grouped together for the usercopy 222 * whitelist region. 223 */ 224 __u16 subscribe; 225 struct sctp_initmsg initmsg; 226 227 int user_frag; 228 229 __u32 autoclose; 230 __u32 adaptation_ind; 231 __u32 pd_point; 232 __u16 nodelay:1, 233 reuse:1, 234 disable_fragments:1, 235 v4mapped:1, 236 frag_interleave:1, 237 strm_interleave:1, 238 recvrcvinfo:1, 239 recvnxtinfo:1, 240 data_ready_signalled:1; 241 242 atomic_t pd_mode; 243 /* Receive to here while partial delivery is in effect. */ 244 struct sk_buff_head pd_lobby; 245 246 /* These must be the last fields, as they will skipped on copies, 247 * like on accept and peeloff operations 248 */ 249 struct list_head auto_asconf_list; 250 int do_auto_asconf; 251 }; 252 253 static inline struct sctp_sock *sctp_sk(const struct sock *sk) 254 { 255 return (struct sctp_sock *)sk; 256 } 257 258 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp) 259 { 260 return (struct sock *)sp; 261 } 262 263 #if IS_ENABLED(CONFIG_IPV6) 264 struct sctp6_sock { 265 struct sctp_sock sctp; 266 struct ipv6_pinfo inet6; 267 }; 268 #endif /* CONFIG_IPV6 */ 269 270 271 /* This is our APPLICATION-SPECIFIC state cookie. 272 * THIS IS NOT DICTATED BY THE SPECIFICATION. 273 */ 274 /* These are the parts of an association which we send in the cookie. 275 * Most of these are straight out of: 276 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB) 277 * 278 */ 279 280 struct sctp_cookie { 281 282 /* My : Tag expected in every inbound packet and sent 283 * Verification: in the INIT or INIT ACK chunk. 284 * Tag : 285 */ 286 __u32 my_vtag; 287 288 /* Peer's : Tag expected in every outbound packet except 289 * Verification: in the INIT chunk. 290 * Tag : 291 */ 292 __u32 peer_vtag; 293 294 /* The rest of these are not from the spec, but really need to 295 * be in the cookie. 296 */ 297 298 /* My Tie Tag : Assist in discovering a restarting association. */ 299 __u32 my_ttag; 300 301 /* Peer's Tie Tag: Assist in discovering a restarting association. */ 302 __u32 peer_ttag; 303 304 /* When does this cookie expire? */ 305 ktime_t expiration; 306 307 /* Number of inbound/outbound streams which are set 308 * and negotiated during the INIT process. 309 */ 310 __u16 sinit_num_ostreams; 311 __u16 sinit_max_instreams; 312 313 /* This is the first sequence number I used. */ 314 __u32 initial_tsn; 315 316 /* This holds the originating address of the INIT packet. */ 317 union sctp_addr peer_addr; 318 319 /* IG Section 2.35.3 320 * Include the source port of the INIT-ACK 321 */ 322 __u16 my_port; 323 324 __u8 prsctp_capable; 325 326 /* Padding for future use */ 327 __u8 padding; 328 329 __u32 adaptation_ind; 330 331 __u8 auth_random[sizeof(struct sctp_paramhdr) + 332 SCTP_AUTH_RANDOM_LENGTH]; 333 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2]; 334 __u8 auth_chunks[sizeof(struct sctp_paramhdr) + SCTP_AUTH_MAX_CHUNKS]; 335 336 /* This is a shim for my peer's INIT packet, followed by 337 * a copy of the raw address list of the association. 338 * The length of the raw address list is saved in the 339 * raw_addr_list_len field, which will be used at the time when 340 * the association TCB is re-constructed from the cookie. 341 */ 342 __u32 raw_addr_list_len; 343 struct sctp_init_chunk peer_init[0]; 344 }; 345 346 347 /* The format of our cookie that we send to our peer. */ 348 struct sctp_signed_cookie { 349 __u8 signature[SCTP_SECRET_SIZE]; 350 __u32 __pad; /* force sctp_cookie alignment to 64 bits */ 351 struct sctp_cookie c; 352 } __packed; 353 354 /* This is another convenience type to allocate memory for address 355 * params for the maximum size and pass such structures around 356 * internally. 357 */ 358 union sctp_addr_param { 359 struct sctp_paramhdr p; 360 struct sctp_ipv4addr_param v4; 361 struct sctp_ipv6addr_param v6; 362 }; 363 364 /* A convenience type to allow walking through the various 365 * parameters and avoid casting all over the place. 366 */ 367 union sctp_params { 368 void *v; 369 struct sctp_paramhdr *p; 370 struct sctp_cookie_preserve_param *life; 371 struct sctp_hostname_param *dns; 372 struct sctp_cookie_param *cookie; 373 struct sctp_supported_addrs_param *sat; 374 struct sctp_ipv4addr_param *v4; 375 struct sctp_ipv6addr_param *v6; 376 union sctp_addr_param *addr; 377 struct sctp_adaptation_ind_param *aind; 378 struct sctp_supported_ext_param *ext; 379 struct sctp_random_param *random; 380 struct sctp_chunks_param *chunks; 381 struct sctp_hmac_algo_param *hmac_algo; 382 struct sctp_addip_param *addip; 383 }; 384 385 /* RFC 2960. Section 3.3.5 Heartbeat. 386 * Heartbeat Information: variable length 387 * The Sender-specific Heartbeat Info field should normally include 388 * information about the sender's current time when this HEARTBEAT 389 * chunk is sent and the destination transport address to which this 390 * HEARTBEAT is sent (see Section 8.3). 391 */ 392 struct sctp_sender_hb_info { 393 struct sctp_paramhdr param_hdr; 394 union sctp_addr daddr; 395 unsigned long sent_at; 396 __u64 hb_nonce; 397 }; 398 399 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt, 400 gfp_t gfp); 401 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid); 402 void sctp_stream_free(struct sctp_stream *stream); 403 void sctp_stream_clear(struct sctp_stream *stream); 404 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new); 405 406 /* What is the current SSN number for this stream? */ 407 #define sctp_ssn_peek(stream, type, sid) \ 408 (sctp_stream_##type((stream), (sid))->ssn) 409 410 /* Return the next SSN number for this stream. */ 411 #define sctp_ssn_next(stream, type, sid) \ 412 (sctp_stream_##type((stream), (sid))->ssn++) 413 414 /* Skip over this ssn and all below. */ 415 #define sctp_ssn_skip(stream, type, sid, ssn) \ 416 (sctp_stream_##type((stream), (sid))->ssn = ssn + 1) 417 418 /* What is the current MID number for this stream? */ 419 #define sctp_mid_peek(stream, type, sid) \ 420 (sctp_stream_##type((stream), (sid))->mid) 421 422 /* Return the next MID number for this stream. */ 423 #define sctp_mid_next(stream, type, sid) \ 424 (sctp_stream_##type((stream), (sid))->mid++) 425 426 /* Skip over this mid and all below. */ 427 #define sctp_mid_skip(stream, type, sid, mid) \ 428 (sctp_stream_##type((stream), (sid))->mid = mid + 1) 429 430 /* What is the current MID_uo number for this stream? */ 431 #define sctp_mid_uo_peek(stream, type, sid) \ 432 (sctp_stream_##type((stream), (sid))->mid_uo) 433 434 /* Return the next MID_uo number for this stream. */ 435 #define sctp_mid_uo_next(stream, type, sid) \ 436 (sctp_stream_##type((stream), (sid))->mid_uo++) 437 438 /* 439 * Pointers to address related SCTP functions. 440 * (i.e. things that depend on the address family.) 441 */ 442 struct sctp_af { 443 int (*sctp_xmit) (struct sk_buff *skb, 444 struct sctp_transport *); 445 int (*setsockopt) (struct sock *sk, 446 int level, 447 int optname, 448 char __user *optval, 449 unsigned int optlen); 450 int (*getsockopt) (struct sock *sk, 451 int level, 452 int optname, 453 char __user *optval, 454 int __user *optlen); 455 int (*compat_setsockopt) (struct sock *sk, 456 int level, 457 int optname, 458 char __user *optval, 459 unsigned int optlen); 460 int (*compat_getsockopt) (struct sock *sk, 461 int level, 462 int optname, 463 char __user *optval, 464 int __user *optlen); 465 void (*get_dst) (struct sctp_transport *t, 466 union sctp_addr *saddr, 467 struct flowi *fl, 468 struct sock *sk); 469 void (*get_saddr) (struct sctp_sock *sk, 470 struct sctp_transport *t, 471 struct flowi *fl); 472 void (*copy_addrlist) (struct list_head *, 473 struct net_device *); 474 int (*cmp_addr) (const union sctp_addr *addr1, 475 const union sctp_addr *addr2); 476 void (*addr_copy) (union sctp_addr *dst, 477 union sctp_addr *src); 478 void (*from_skb) (union sctp_addr *, 479 struct sk_buff *skb, 480 int saddr); 481 void (*from_sk) (union sctp_addr *, 482 struct sock *sk); 483 void (*from_addr_param) (union sctp_addr *, 484 union sctp_addr_param *, 485 __be16 port, int iif); 486 int (*to_addr_param) (const union sctp_addr *, 487 union sctp_addr_param *); 488 int (*addr_valid) (union sctp_addr *, 489 struct sctp_sock *, 490 const struct sk_buff *); 491 enum sctp_scope (*scope)(union sctp_addr *); 492 void (*inaddr_any) (union sctp_addr *, __be16); 493 int (*is_any) (const union sctp_addr *); 494 int (*available) (union sctp_addr *, 495 struct sctp_sock *); 496 int (*skb_iif) (const struct sk_buff *sk); 497 int (*is_ce) (const struct sk_buff *sk); 498 void (*seq_dump_addr)(struct seq_file *seq, 499 union sctp_addr *addr); 500 void (*ecn_capable)(struct sock *sk); 501 __u16 net_header_len; 502 int sockaddr_len; 503 int (*ip_options_len)(struct sock *sk); 504 sa_family_t sa_family; 505 struct list_head list; 506 }; 507 508 struct sctp_af *sctp_get_af_specific(sa_family_t); 509 int sctp_register_af(struct sctp_af *); 510 511 /* Protocol family functions. */ 512 struct sctp_pf { 513 void (*event_msgname)(struct sctp_ulpevent *, char *, int *); 514 void (*skb_msgname) (struct sk_buff *, char *, int *); 515 int (*af_supported) (sa_family_t, struct sctp_sock *); 516 int (*cmp_addr) (const union sctp_addr *, 517 const union sctp_addr *, 518 struct sctp_sock *); 519 int (*bind_verify) (struct sctp_sock *, union sctp_addr *); 520 int (*send_verify) (struct sctp_sock *, union sctp_addr *); 521 int (*supported_addrs)(const struct sctp_sock *, __be16 *); 522 struct sock *(*create_accept_sk) (struct sock *sk, 523 struct sctp_association *asoc, 524 bool kern); 525 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr); 526 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk); 527 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk); 528 void (*copy_ip_options)(struct sock *sk, struct sock *newsk); 529 struct sctp_af *af; 530 }; 531 532 533 /* Structure to track chunk fragments that have been acked, but peer 534 * fragments of the same message have not. 535 */ 536 struct sctp_datamsg { 537 /* Chunks waiting to be submitted to lower layer. */ 538 struct list_head chunks; 539 /* Reference counting. */ 540 refcount_t refcnt; 541 /* When is this message no longer interesting to the peer? */ 542 unsigned long expires_at; 543 /* Did the messenge fail to send? */ 544 int send_error; 545 u8 send_failed:1, 546 can_delay:1, /* should this message be Nagle delayed */ 547 abandoned:1; /* should this message be abandoned */ 548 }; 549 550 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *, 551 struct sctp_sndrcvinfo *, 552 struct iov_iter *); 553 void sctp_datamsg_free(struct sctp_datamsg *); 554 void sctp_datamsg_put(struct sctp_datamsg *); 555 void sctp_chunk_fail(struct sctp_chunk *, int error); 556 int sctp_chunk_abandoned(struct sctp_chunk *); 557 558 /* RFC2960 1.4 Key Terms 559 * 560 * o Chunk: A unit of information within an SCTP packet, consisting of 561 * a chunk header and chunk-specific content. 562 * 563 * As a matter of convenience, we remember the SCTP common header for 564 * each chunk as well as a few other header pointers... 565 */ 566 struct sctp_chunk { 567 struct list_head list; 568 569 refcount_t refcnt; 570 571 /* How many times this chunk have been sent, for prsctp RTX policy */ 572 int sent_count; 573 574 union { 575 /* This is our link to the per-transport transmitted list. */ 576 struct list_head transmitted_list; 577 /* List in specific stream outq */ 578 struct list_head stream_list; 579 }; 580 581 /* This field is used by chunks that hold fragmented data. 582 * For the first fragment this is the list that holds the rest of 583 * fragments. For the remaining fragments, this is the link to the 584 * frag_list maintained in the first fragment. 585 */ 586 struct list_head frag_list; 587 588 /* This points to the sk_buff containing the actual data. */ 589 struct sk_buff *skb; 590 591 union { 592 /* In case of GSO packets, this will store the head one */ 593 struct sk_buff *head_skb; 594 /* In case of auth enabled, this will point to the shkey */ 595 struct sctp_shared_key *shkey; 596 }; 597 598 /* These are the SCTP headers by reverse order in a packet. 599 * Note that some of these may happen more than once. In that 600 * case, we point at the "current" one, whatever that means 601 * for that level of header. 602 */ 603 604 /* We point this at the FIRST TLV parameter to chunk_hdr. */ 605 union sctp_params param_hdr; 606 union { 607 __u8 *v; 608 struct sctp_datahdr *data_hdr; 609 struct sctp_inithdr *init_hdr; 610 struct sctp_sackhdr *sack_hdr; 611 struct sctp_heartbeathdr *hb_hdr; 612 struct sctp_sender_hb_info *hbs_hdr; 613 struct sctp_shutdownhdr *shutdown_hdr; 614 struct sctp_signed_cookie *cookie_hdr; 615 struct sctp_ecnehdr *ecne_hdr; 616 struct sctp_cwrhdr *ecn_cwr_hdr; 617 struct sctp_errhdr *err_hdr; 618 struct sctp_addiphdr *addip_hdr; 619 struct sctp_fwdtsn_hdr *fwdtsn_hdr; 620 struct sctp_authhdr *auth_hdr; 621 struct sctp_idatahdr *idata_hdr; 622 struct sctp_ifwdtsn_hdr *ifwdtsn_hdr; 623 } subh; 624 625 __u8 *chunk_end; 626 627 struct sctp_chunkhdr *chunk_hdr; 628 struct sctphdr *sctp_hdr; 629 630 /* This needs to be recoverable for SCTP_SEND_FAILED events. */ 631 struct sctp_sndrcvinfo sinfo; 632 633 /* Which association does this belong to? */ 634 struct sctp_association *asoc; 635 636 /* What endpoint received this chunk? */ 637 struct sctp_ep_common *rcvr; 638 639 /* We fill this in if we are calculating RTT. */ 640 unsigned long sent_at; 641 642 /* What is the origin IP address for this chunk? */ 643 union sctp_addr source; 644 /* Destination address for this chunk. */ 645 union sctp_addr dest; 646 647 /* For outbound message, track all fragments for SEND_FAILED. */ 648 struct sctp_datamsg *msg; 649 650 /* For an inbound chunk, this tells us where it came from. 651 * For an outbound chunk, it tells us where we'd like it to 652 * go. It is NULL if we have no preference. 653 */ 654 struct sctp_transport *transport; 655 656 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO 657 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH 658 * spec violates the principle premis that all chunks are processed 659 * in order. 660 */ 661 struct sk_buff *auth_chunk; 662 663 #define SCTP_CAN_FRTX 0x0 664 #define SCTP_NEED_FRTX 0x1 665 #define SCTP_DONT_FRTX 0x2 666 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */ 667 has_tsn:1, /* Does this chunk have a TSN yet? */ 668 has_ssn:1, /* Does this chunk have a SSN yet? */ 669 #define has_mid has_ssn 670 singleton:1, /* Only chunk in the packet? */ 671 end_of_packet:1, /* Last chunk in the packet? */ 672 ecn_ce_done:1, /* Have we processed the ECN CE bit? */ 673 pdiscard:1, /* Discard the whole packet now? */ 674 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */ 675 data_accepted:1, /* At least 1 chunk accepted */ 676 auth:1, /* IN: was auth'ed | OUT: needs auth */ 677 has_asconf:1, /* IN: have seen an asconf before */ 678 tsn_missing_report:2, /* Data chunk missing counter. */ 679 fast_retransmit:2; /* Is this chunk fast retransmitted? */ 680 }; 681 682 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1) 683 void sctp_chunk_hold(struct sctp_chunk *); 684 void sctp_chunk_put(struct sctp_chunk *); 685 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len, 686 struct iov_iter *from); 687 void sctp_chunk_free(struct sctp_chunk *); 688 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data); 689 struct sctp_chunk *sctp_chunkify(struct sk_buff *, 690 const struct sctp_association *, 691 struct sock *, gfp_t gfp); 692 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *, 693 union sctp_addr *); 694 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk); 695 696 static inline __u16 sctp_chunk_stream_no(struct sctp_chunk *ch) 697 { 698 return ntohs(ch->subh.data_hdr->stream); 699 } 700 701 enum { 702 SCTP_ADDR_NEW, /* new address added to assoc/ep */ 703 SCTP_ADDR_SRC, /* address can be used as source */ 704 SCTP_ADDR_DEL, /* address about to be deleted */ 705 }; 706 707 /* This is a structure for holding either an IPv6 or an IPv4 address. */ 708 struct sctp_sockaddr_entry { 709 struct list_head list; 710 struct rcu_head rcu; 711 union sctp_addr a; 712 __u8 state; 713 __u8 valid; 714 }; 715 716 #define SCTP_ADDRESS_TICK_DELAY 500 717 718 /* This structure holds lists of chunks as we are assembling for 719 * transmission. 720 */ 721 struct sctp_packet { 722 /* These are the SCTP header values (host order) for the packet. */ 723 __u16 source_port; 724 __u16 destination_port; 725 __u32 vtag; 726 727 /* This contains the payload chunks. */ 728 struct list_head chunk_list; 729 730 /* This is the overhead of the sctp and ip headers. */ 731 size_t overhead; 732 /* This is the total size of all chunks INCLUDING padding. */ 733 size_t size; 734 /* This is the maximum size this packet may have */ 735 size_t max_size; 736 737 /* The packet is destined for this transport address. 738 * The function we finally use to pass down to the next lower 739 * layer lives in the transport structure. 740 */ 741 struct sctp_transport *transport; 742 743 /* pointer to the auth chunk for this packet */ 744 struct sctp_chunk *auth; 745 746 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */ 747 has_sack:1, /* This packet contains a SACK chunk. */ 748 has_auth:1, /* This packet contains an AUTH chunk */ 749 has_data:1, /* This packet contains at least 1 DATA chunk */ 750 ipfragok:1; /* So let ip fragment this packet */ 751 }; 752 753 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *, 754 __u16 sport, __u16 dport); 755 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int); 756 enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet, 757 struct sctp_chunk *chunk, 758 int one_packet, gfp_t gfp); 759 enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet, 760 struct sctp_chunk *chunk); 761 int sctp_packet_transmit(struct sctp_packet *, gfp_t); 762 void sctp_packet_free(struct sctp_packet *); 763 764 static inline int sctp_packet_empty(struct sctp_packet *packet) 765 { 766 return packet->size == packet->overhead; 767 } 768 769 /* This represents a remote transport address. 770 * For local transport addresses, we just use union sctp_addr. 771 * 772 * RFC2960 Section 1.4 Key Terms 773 * 774 * o Transport address: A Transport Address is traditionally defined 775 * by Network Layer address, Transport Layer protocol and Transport 776 * Layer port number. In the case of SCTP running over IP, a 777 * transport address is defined by the combination of an IP address 778 * and an SCTP port number (where SCTP is the Transport protocol). 779 * 780 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control 781 * 782 * o The sender keeps a separate congestion control parameter set for 783 * each of the destination addresses it can send to (not each 784 * source-destination pair but for each destination). The parameters 785 * should decay if the address is not used for a long enough time 786 * period. 787 * 788 */ 789 struct sctp_transport { 790 /* A list of transports. */ 791 struct list_head transports; 792 struct rhlist_head node; 793 794 /* Reference counting. */ 795 refcount_t refcnt; 796 /* RTO-Pending : A flag used to track if one of the DATA 797 * chunks sent to this address is currently being 798 * used to compute a RTT. If this flag is 0, 799 * the next DATA chunk sent to this destination 800 * should be used to compute a RTT and this flag 801 * should be set. Every time the RTT 802 * calculation completes (i.e. the DATA chunk 803 * is SACK'd) clear this flag. 804 */ 805 __u32 rto_pending:1, 806 807 /* 808 * hb_sent : a flag that signals that we have a pending 809 * heartbeat. 810 */ 811 hb_sent:1, 812 813 /* Is the Path MTU update pending on this tranport */ 814 pmtu_pending:1, 815 816 dst_pending_confirm:1, /* need to confirm neighbour */ 817 818 /* Has this transport moved the ctsn since we last sacked */ 819 sack_generation:1; 820 u32 dst_cookie; 821 822 struct flowi fl; 823 824 /* This is the peer's IP address and port. */ 825 union sctp_addr ipaddr; 826 827 /* These are the functions we call to handle LLP stuff. */ 828 struct sctp_af *af_specific; 829 830 /* Which association do we belong to? */ 831 struct sctp_association *asoc; 832 833 /* RFC2960 834 * 835 * 12.3 Per Transport Address Data 836 * 837 * For each destination transport address in the peer's 838 * address list derived from the INIT or INIT ACK chunk, a 839 * number of data elements needs to be maintained including: 840 */ 841 /* RTO : The current retransmission timeout value. */ 842 unsigned long rto; 843 844 __u32 rtt; /* This is the most recent RTT. */ 845 846 /* RTTVAR : The current RTT variation. */ 847 __u32 rttvar; 848 849 /* SRTT : The current smoothed round trip time. */ 850 __u32 srtt; 851 852 /* 853 * These are the congestion stats. 854 */ 855 /* cwnd : The current congestion window. */ 856 __u32 cwnd; /* This is the actual cwnd. */ 857 858 /* ssthresh : The current slow start threshold value. */ 859 __u32 ssthresh; 860 861 /* partial : The tracking method for increase of cwnd when in 862 * bytes acked : congestion avoidance mode (see Section 6.2.2) 863 */ 864 __u32 partial_bytes_acked; 865 866 /* Data that has been sent, but not acknowledged. */ 867 __u32 flight_size; 868 869 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */ 870 871 /* Destination */ 872 struct dst_entry *dst; 873 /* Source address. */ 874 union sctp_addr saddr; 875 876 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 877 * the destination address every heartbeat interval. 878 */ 879 unsigned long hbinterval; 880 881 /* SACK delay timeout */ 882 unsigned long sackdelay; 883 __u32 sackfreq; 884 885 atomic_t mtu_info; 886 887 /* When was the last time that we heard from this transport? We use 888 * this to pick new active and retran paths. 889 */ 890 ktime_t last_time_heard; 891 892 /* When was the last time that we sent a chunk using this 893 * transport? We use this to check for idle transports 894 */ 895 unsigned long last_time_sent; 896 897 /* Last time(in jiffies) when cwnd is reduced due to the congestion 898 * indication based on ECNE chunk. 899 */ 900 unsigned long last_time_ecne_reduced; 901 902 /* This is the max_retrans value for the transport and will 903 * be initialized from the assocs value. This can be changed 904 * using the SCTP_SET_PEER_ADDR_PARAMS socket option. 905 */ 906 __u16 pathmaxrxt; 907 908 __u32 flowlabel; 909 __u8 dscp; 910 911 /* This is the partially failed retrans value for the transport 912 * and will be initialized from the assocs value. This can be changed 913 * using the SCTP_PEER_ADDR_THLDS socket option 914 */ 915 int pf_retrans; 916 /* PMTU : The current known path MTU. */ 917 __u32 pathmtu; 918 919 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 920 __u32 param_flags; 921 922 /* The number of times INIT has been sent on this transport. */ 923 int init_sent_count; 924 925 /* state : The current state of this destination, 926 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN. 927 */ 928 int state; 929 930 /* These are the error stats for this destination. */ 931 932 /* Error count : The current error count for this destination. */ 933 unsigned short error_count; 934 935 /* Per : A timer used by each destination. 936 * Destination : 937 * Timer : 938 * 939 * [Everywhere else in the text this is called T3-rtx. -ed] 940 */ 941 struct timer_list T3_rtx_timer; 942 943 /* Heartbeat timer is per destination. */ 944 struct timer_list hb_timer; 945 946 /* Timer to handle ICMP proto unreachable envets */ 947 struct timer_list proto_unreach_timer; 948 949 /* Timer to handler reconf chunk rtx */ 950 struct timer_list reconf_timer; 951 952 /* Since we're using per-destination retransmission timers 953 * (see above), we're also using per-destination "transmitted" 954 * queues. This probably ought to be a private struct 955 * accessible only within the outqueue, but it's not, yet. 956 */ 957 struct list_head transmitted; 958 959 /* We build bundle-able packets for this transport here. */ 960 struct sctp_packet packet; 961 962 /* This is the list of transports that have chunks to send. */ 963 struct list_head send_ready; 964 965 /* State information saved for SFR_CACC algorithm. The key 966 * idea in SFR_CACC is to maintain state at the sender on a 967 * per-destination basis when a changeover happens. 968 * char changeover_active; 969 * char cycling_changeover; 970 * __u32 next_tsn_at_change; 971 * char cacc_saw_newack; 972 */ 973 struct { 974 /* An unsigned integer, which stores the next TSN to be 975 * used by the sender, at the moment of changeover. 976 */ 977 __u32 next_tsn_at_change; 978 979 /* A flag which indicates the occurrence of a changeover */ 980 char changeover_active; 981 982 /* A flag which indicates whether the change of primary is 983 * the first switch to this destination address during an 984 * active switch. 985 */ 986 char cycling_changeover; 987 988 /* A temporary flag, which is used during the processing of 989 * a SACK to estimate the causative TSN(s)'s group. 990 */ 991 char cacc_saw_newack; 992 } cacc; 993 994 /* 64-bit random number sent with heartbeat. */ 995 __u64 hb_nonce; 996 997 struct rcu_head rcu; 998 }; 999 1000 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *, 1001 gfp_t); 1002 void sctp_transport_set_owner(struct sctp_transport *, 1003 struct sctp_association *); 1004 void sctp_transport_route(struct sctp_transport *, union sctp_addr *, 1005 struct sctp_sock *); 1006 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk); 1007 void sctp_transport_free(struct sctp_transport *); 1008 void sctp_transport_reset_t3_rtx(struct sctp_transport *); 1009 void sctp_transport_reset_hb_timer(struct sctp_transport *); 1010 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport); 1011 int sctp_transport_hold(struct sctp_transport *); 1012 void sctp_transport_put(struct sctp_transport *); 1013 void sctp_transport_update_rto(struct sctp_transport *, __u32); 1014 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32); 1015 void sctp_transport_lower_cwnd(struct sctp_transport *t, 1016 enum sctp_lower_cwnd reason); 1017 void sctp_transport_burst_limited(struct sctp_transport *); 1018 void sctp_transport_burst_reset(struct sctp_transport *); 1019 unsigned long sctp_transport_timeout(struct sctp_transport *); 1020 void sctp_transport_reset(struct sctp_transport *t); 1021 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu); 1022 void sctp_transport_immediate_rtx(struct sctp_transport *); 1023 void sctp_transport_dst_release(struct sctp_transport *t); 1024 void sctp_transport_dst_confirm(struct sctp_transport *t); 1025 1026 1027 /* This is the structure we use to queue packets as they come into 1028 * SCTP. We write packets to it and read chunks from it. 1029 */ 1030 struct sctp_inq { 1031 /* This is actually a queue of sctp_chunk each 1032 * containing a partially decoded packet. 1033 */ 1034 struct list_head in_chunk_list; 1035 /* This is the packet which is currently off the in queue and is 1036 * being worked on through the inbound chunk processing. 1037 */ 1038 struct sctp_chunk *in_progress; 1039 1040 /* This is the delayed task to finish delivering inbound 1041 * messages. 1042 */ 1043 struct work_struct immediate; 1044 }; 1045 1046 void sctp_inq_init(struct sctp_inq *); 1047 void sctp_inq_free(struct sctp_inq *); 1048 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet); 1049 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *); 1050 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *); 1051 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t); 1052 1053 /* This is the structure we use to hold outbound chunks. You push 1054 * chunks in and they automatically pop out the other end as bundled 1055 * packets (it calls (*output_handler)()). 1056 * 1057 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1, 1058 * and 8.2 of the v13 draft. 1059 * 1060 * It handles retransmissions. The connection to the timeout portion 1061 * of the state machine is through sctp_..._timeout() and timeout_handler. 1062 * 1063 * If you feed it SACKs, it will eat them. 1064 * 1065 * If you give it big chunks, it will fragment them. 1066 * 1067 * It assigns TSN's to data chunks. This happens at the last possible 1068 * instant before transmission. 1069 * 1070 * When free()'d, it empties itself out via output_handler(). 1071 */ 1072 struct sctp_outq { 1073 struct sctp_association *asoc; 1074 1075 /* Data pending that has never been transmitted. */ 1076 struct list_head out_chunk_list; 1077 1078 /* Stream scheduler being used */ 1079 struct sctp_sched_ops *sched; 1080 1081 unsigned int out_qlen; /* Total length of queued data chunks. */ 1082 1083 /* Error of send failed, may used in SCTP_SEND_FAILED event. */ 1084 unsigned int error; 1085 1086 /* These are control chunks we want to send. */ 1087 struct list_head control_chunk_list; 1088 1089 /* These are chunks that have been sacked but are above the 1090 * CTSN, or cumulative tsn ack point. 1091 */ 1092 struct list_head sacked; 1093 1094 /* Put chunks on this list to schedule them for 1095 * retransmission. 1096 */ 1097 struct list_head retransmit; 1098 1099 /* Put chunks on this list to save them for FWD TSN processing as 1100 * they were abandoned. 1101 */ 1102 struct list_head abandoned; 1103 1104 /* How many unackd bytes do we have in-flight? */ 1105 __u32 outstanding_bytes; 1106 1107 /* Are we doing fast-rtx on this queue */ 1108 char fast_rtx; 1109 1110 /* Corked? */ 1111 char cork; 1112 }; 1113 1114 void sctp_outq_init(struct sctp_association *, struct sctp_outq *); 1115 void sctp_outq_teardown(struct sctp_outq *); 1116 void sctp_outq_free(struct sctp_outq*); 1117 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t); 1118 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *); 1119 int sctp_outq_is_empty(const struct sctp_outq *); 1120 void sctp_outq_restart(struct sctp_outq *); 1121 1122 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport, 1123 enum sctp_retransmit_reason reason); 1124 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8); 1125 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp); 1126 void sctp_prsctp_prune(struct sctp_association *asoc, 1127 struct sctp_sndrcvinfo *sinfo, int msg_len); 1128 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn); 1129 /* Uncork and flush an outqueue. */ 1130 static inline void sctp_outq_cork(struct sctp_outq *q) 1131 { 1132 q->cork = 1; 1133 } 1134 1135 /* SCTP skb control block. 1136 * sctp_input_cb is currently used on rx and sock rx queue 1137 */ 1138 struct sctp_input_cb { 1139 union { 1140 struct inet_skb_parm h4; 1141 #if IS_ENABLED(CONFIG_IPV6) 1142 struct inet6_skb_parm h6; 1143 #endif 1144 } header; 1145 struct sctp_chunk *chunk; 1146 struct sctp_af *af; 1147 }; 1148 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0])) 1149 1150 struct sctp_output_cb { 1151 struct sk_buff *last; 1152 }; 1153 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0])) 1154 1155 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb) 1156 { 1157 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; 1158 1159 return chunk->head_skb ? : skb; 1160 } 1161 1162 /* These bind address data fields common between endpoints and associations */ 1163 struct sctp_bind_addr { 1164 1165 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1166 * 1167 * SCTP Port: The local SCTP port number the endpoint is 1168 * bound to. 1169 */ 1170 __u16 port; 1171 1172 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1173 * 1174 * Address List: The list of IP addresses that this instance 1175 * has bound. This information is passed to one's 1176 * peer(s) in INIT and INIT ACK chunks. 1177 */ 1178 struct list_head address_list; 1179 }; 1180 1181 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port); 1182 void sctp_bind_addr_free(struct sctp_bind_addr *); 1183 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest, 1184 const struct sctp_bind_addr *src, 1185 enum sctp_scope scope, gfp_t gfp, 1186 int flags); 1187 int sctp_bind_addr_dup(struct sctp_bind_addr *dest, 1188 const struct sctp_bind_addr *src, 1189 gfp_t gfp); 1190 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *, 1191 int new_size, __u8 addr_state, gfp_t gfp); 1192 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *); 1193 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *, 1194 struct sctp_sock *); 1195 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *, 1196 struct sctp_sock *, struct sctp_sock *); 1197 int sctp_bind_addr_state(const struct sctp_bind_addr *bp, 1198 const union sctp_addr *addr); 1199 int sctp_bind_addrs_check(struct sctp_sock *sp, 1200 struct sctp_sock *sp2, int cnt2); 1201 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp, 1202 const union sctp_addr *addrs, 1203 int addrcnt, 1204 struct sctp_sock *opt); 1205 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp, 1206 int *addrs_len, 1207 gfp_t gfp); 1208 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len, 1209 __u16 port, gfp_t gfp); 1210 1211 enum sctp_scope sctp_scope(const union sctp_addr *addr); 1212 int sctp_in_scope(struct net *net, const union sctp_addr *addr, 1213 const enum sctp_scope scope); 1214 int sctp_is_any(struct sock *sk, const union sctp_addr *addr); 1215 int sctp_is_ep_boundall(struct sock *sk); 1216 1217 1218 /* What type of endpoint? */ 1219 enum sctp_endpoint_type { 1220 SCTP_EP_TYPE_SOCKET, 1221 SCTP_EP_TYPE_ASSOCIATION, 1222 }; 1223 1224 /* 1225 * A common base class to bridge the implmentation view of a 1226 * socket (usually listening) endpoint versus an association's 1227 * local endpoint. 1228 * This common structure is useful for several purposes: 1229 * 1) Common interface for lookup routines. 1230 * a) Subfunctions work for either endpoint or association 1231 * b) Single interface to lookup allows hiding the lookup lock rather 1232 * than acquiring it externally. 1233 * 2) Common interface for the inbound chunk handling/state machine. 1234 * 3) Common object handling routines for reference counting, etc. 1235 * 4) Disentangle association lookup from endpoint lookup, where we 1236 * do not have to find our endpoint to find our association. 1237 * 1238 */ 1239 1240 struct sctp_ep_common { 1241 /* Fields to help us manage our entries in the hash tables. */ 1242 struct hlist_node node; 1243 int hashent; 1244 1245 /* Runtime type information. What kind of endpoint is this? */ 1246 enum sctp_endpoint_type type; 1247 1248 /* Some fields to help us manage this object. 1249 * refcnt - Reference count access to this object. 1250 * dead - Do not attempt to use this object. 1251 */ 1252 refcount_t refcnt; 1253 bool dead; 1254 1255 /* What socket does this endpoint belong to? */ 1256 struct sock *sk; 1257 1258 /* This is where we receive inbound chunks. */ 1259 struct sctp_inq inqueue; 1260 1261 /* This substructure includes the defining parameters of the 1262 * endpoint: 1263 * bind_addr.port is our shared port number. 1264 * bind_addr.address_list is our set of local IP addresses. 1265 */ 1266 struct sctp_bind_addr bind_addr; 1267 }; 1268 1269 1270 /* RFC Section 1.4 Key Terms 1271 * 1272 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a 1273 * multi-homed host, an SCTP endpoint is represented to its peers as a 1274 * combination of a set of eligible destination transport addresses to 1275 * which SCTP packets can be sent and a set of eligible source 1276 * transport addresses from which SCTP packets can be received. 1277 * All transport addresses used by an SCTP endpoint must use the 1278 * same port number, but can use multiple IP addresses. A transport 1279 * address used by an SCTP endpoint must not be used by another 1280 * SCTP endpoint. In other words, a transport address is unique 1281 * to an SCTP endpoint. 1282 * 1283 * From an implementation perspective, each socket has one of these. 1284 * A TCP-style socket will have exactly one association on one of 1285 * these. An UDP-style socket will have multiple associations hanging 1286 * off one of these. 1287 */ 1288 1289 struct sctp_endpoint { 1290 /* Common substructure for endpoint and association. */ 1291 struct sctp_ep_common base; 1292 1293 /* Associations: A list of current associations and mappings 1294 * to the data consumers for each association. This 1295 * may be in the form of a hash table or other 1296 * implementation dependent structure. The data 1297 * consumers may be process identification 1298 * information such as file descriptors, named pipe 1299 * pointer, or table pointers dependent on how SCTP 1300 * is implemented. 1301 */ 1302 /* This is really a list of struct sctp_association entries. */ 1303 struct list_head asocs; 1304 1305 /* Secret Key: A secret key used by this endpoint to compute 1306 * the MAC. This SHOULD be a cryptographic quality 1307 * random number with a sufficient length. 1308 * Discussion in [RFC1750] can be helpful in 1309 * selection of the key. 1310 */ 1311 __u8 secret_key[SCTP_SECRET_SIZE]; 1312 1313 /* digest: This is a digest of the sctp cookie. This field is 1314 * only used on the receive path when we try to validate 1315 * that the cookie has not been tampered with. We put 1316 * this here so we pre-allocate this once and can re-use 1317 * on every receive. 1318 */ 1319 __u8 *digest; 1320 1321 /* sendbuf acct. policy. */ 1322 __u32 sndbuf_policy; 1323 1324 /* rcvbuf acct. policy. */ 1325 __u32 rcvbuf_policy; 1326 1327 /* SCTP AUTH: array of the HMACs that will be allocated 1328 * we need this per association so that we don't serialize 1329 */ 1330 struct crypto_shash **auth_hmacs; 1331 1332 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */ 1333 struct sctp_hmac_algo_param *auth_hmacs_list; 1334 1335 /* SCTP-AUTH: chunks to authenticate encoded into parameter */ 1336 struct sctp_chunks_param *auth_chunk_list; 1337 1338 /* SCTP-AUTH: endpoint shared keys */ 1339 struct list_head endpoint_shared_keys; 1340 __u16 active_key_id; 1341 __u8 auth_enable:1, 1342 prsctp_enable:1, 1343 reconf_enable:1; 1344 1345 __u8 strreset_enable; 1346 1347 /* Security identifiers from incoming (INIT). These are set by 1348 * security_sctp_assoc_request(). These will only be used by 1349 * SCTP TCP type sockets and peeled off connections as they 1350 * cause a new socket to be generated. security_sctp_sk_clone() 1351 * will then plug these into the new socket. 1352 */ 1353 1354 u32 secid; 1355 u32 peer_secid; 1356 }; 1357 1358 /* Recover the outter endpoint structure. */ 1359 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base) 1360 { 1361 struct sctp_endpoint *ep; 1362 1363 ep = container_of(base, struct sctp_endpoint, base); 1364 return ep; 1365 } 1366 1367 /* These are function signatures for manipulating endpoints. */ 1368 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t); 1369 void sctp_endpoint_free(struct sctp_endpoint *); 1370 void sctp_endpoint_put(struct sctp_endpoint *); 1371 void sctp_endpoint_hold(struct sctp_endpoint *); 1372 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *); 1373 struct sctp_association *sctp_endpoint_lookup_assoc( 1374 const struct sctp_endpoint *ep, 1375 const union sctp_addr *paddr, 1376 struct sctp_transport **); 1377 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep, 1378 const union sctp_addr *paddr); 1379 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *, 1380 struct net *, const union sctp_addr *); 1381 bool sctp_has_association(struct net *net, const union sctp_addr *laddr, 1382 const union sctp_addr *paddr); 1383 1384 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep, 1385 const struct sctp_association *asoc, 1386 enum sctp_cid cid, struct sctp_init_chunk *peer_init, 1387 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk); 1388 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk, 1389 const union sctp_addr *peer, 1390 struct sctp_init_chunk *init, gfp_t gfp); 1391 __u32 sctp_generate_tag(const struct sctp_endpoint *); 1392 __u32 sctp_generate_tsn(const struct sctp_endpoint *); 1393 1394 struct sctp_inithdr_host { 1395 __u32 init_tag; 1396 __u32 a_rwnd; 1397 __u16 num_outbound_streams; 1398 __u16 num_inbound_streams; 1399 __u32 initial_tsn; 1400 }; 1401 1402 struct sctp_stream_priorities { 1403 /* List of priorities scheduled */ 1404 struct list_head prio_sched; 1405 /* List of streams scheduled */ 1406 struct list_head active; 1407 /* The next stream stream in line */ 1408 struct sctp_stream_out_ext *next; 1409 __u16 prio; 1410 }; 1411 1412 struct sctp_stream_out_ext { 1413 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 1414 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 1415 struct list_head outq; /* chunks enqueued by this stream */ 1416 union { 1417 struct { 1418 /* Scheduled streams list */ 1419 struct list_head prio_list; 1420 struct sctp_stream_priorities *prio_head; 1421 }; 1422 /* Fields used by RR scheduler */ 1423 struct { 1424 struct list_head rr_list; 1425 }; 1426 }; 1427 }; 1428 1429 struct sctp_stream_out { 1430 union { 1431 __u32 mid; 1432 __u16 ssn; 1433 }; 1434 __u32 mid_uo; 1435 struct sctp_stream_out_ext *ext; 1436 __u8 state; 1437 }; 1438 1439 struct sctp_stream_in { 1440 union { 1441 __u32 mid; 1442 __u16 ssn; 1443 }; 1444 __u32 mid_uo; 1445 __u32 fsn; 1446 __u32 fsn_uo; 1447 char pd_mode; 1448 char pd_mode_uo; 1449 }; 1450 1451 struct sctp_stream { 1452 GENRADIX(struct sctp_stream_out) out; 1453 GENRADIX(struct sctp_stream_in) in; 1454 1455 __u16 outcnt; 1456 __u16 incnt; 1457 /* Current stream being sent, if any */ 1458 struct sctp_stream_out *out_curr; 1459 union { 1460 /* Fields used by priority scheduler */ 1461 struct { 1462 /* List of priorities scheduled */ 1463 struct list_head prio_list; 1464 }; 1465 /* Fields used by RR scheduler */ 1466 struct { 1467 /* List of streams scheduled */ 1468 struct list_head rr_list; 1469 /* The next stream stream in line */ 1470 struct sctp_stream_out_ext *rr_next; 1471 }; 1472 }; 1473 struct sctp_stream_interleave *si; 1474 }; 1475 1476 static inline struct sctp_stream_out *sctp_stream_out( 1477 struct sctp_stream *stream, 1478 __u16 sid) 1479 { 1480 return genradix_ptr(&stream->out, sid); 1481 } 1482 1483 static inline struct sctp_stream_in *sctp_stream_in( 1484 struct sctp_stream *stream, 1485 __u16 sid) 1486 { 1487 return genradix_ptr(&stream->in, sid); 1488 } 1489 1490 #define SCTP_SO(s, i) sctp_stream_out((s), (i)) 1491 #define SCTP_SI(s, i) sctp_stream_in((s), (i)) 1492 1493 #define SCTP_STREAM_CLOSED 0x00 1494 #define SCTP_STREAM_OPEN 0x01 1495 1496 static inline __u16 sctp_datachk_len(const struct sctp_stream *stream) 1497 { 1498 return stream->si->data_chunk_len; 1499 } 1500 1501 static inline __u16 sctp_datahdr_len(const struct sctp_stream *stream) 1502 { 1503 return stream->si->data_chunk_len - sizeof(struct sctp_chunkhdr); 1504 } 1505 1506 static inline __u16 sctp_ftsnchk_len(const struct sctp_stream *stream) 1507 { 1508 return stream->si->ftsn_chunk_len; 1509 } 1510 1511 static inline __u16 sctp_ftsnhdr_len(const struct sctp_stream *stream) 1512 { 1513 return stream->si->ftsn_chunk_len - sizeof(struct sctp_chunkhdr); 1514 } 1515 1516 /* SCTP_GET_ASSOC_STATS counters */ 1517 struct sctp_priv_assoc_stats { 1518 /* Maximum observed rto in the association during subsequent 1519 * observations. Value is set to 0 if no RTO measurement took place 1520 * The transport where the max_rto was observed is returned in 1521 * obs_rto_ipaddr 1522 */ 1523 struct sockaddr_storage obs_rto_ipaddr; 1524 __u64 max_obs_rto; 1525 /* Total In and Out SACKs received and sent */ 1526 __u64 isacks; 1527 __u64 osacks; 1528 /* Total In and Out packets received and sent */ 1529 __u64 opackets; 1530 __u64 ipackets; 1531 /* Total retransmitted chunks */ 1532 __u64 rtxchunks; 1533 /* TSN received > next expected */ 1534 __u64 outofseqtsns; 1535 /* Duplicate Chunks received */ 1536 __u64 idupchunks; 1537 /* Gap Ack Blocks received */ 1538 __u64 gapcnt; 1539 /* Unordered data chunks sent and received */ 1540 __u64 ouodchunks; 1541 __u64 iuodchunks; 1542 /* Ordered data chunks sent and received */ 1543 __u64 oodchunks; 1544 __u64 iodchunks; 1545 /* Control chunks sent and received */ 1546 __u64 octrlchunks; 1547 __u64 ictrlchunks; 1548 }; 1549 1550 /* RFC2960 1551 * 1552 * 12. Recommended Transmission Control Block (TCB) Parameters 1553 * 1554 * This section details a recommended set of parameters that should 1555 * be contained within the TCB for an implementation. This section is 1556 * for illustrative purposes and should not be deemed as requirements 1557 * on an implementation or as an exhaustive list of all parameters 1558 * inside an SCTP TCB. Each implementation may need its own additional 1559 * parameters for optimization. 1560 */ 1561 1562 1563 /* Here we have information about each individual association. */ 1564 struct sctp_association { 1565 1566 /* A base structure common to endpoint and association. 1567 * In this context, it represents the associations's view 1568 * of the local endpoint of the association. 1569 */ 1570 struct sctp_ep_common base; 1571 1572 /* Associations on the same socket. */ 1573 struct list_head asocs; 1574 1575 /* association id. */ 1576 sctp_assoc_t assoc_id; 1577 1578 /* This is our parent endpoint. */ 1579 struct sctp_endpoint *ep; 1580 1581 /* These are those association elements needed in the cookie. */ 1582 struct sctp_cookie c; 1583 1584 /* This is all information about our peer. */ 1585 struct { 1586 /* transport_addr_list 1587 * 1588 * Peer : A list of SCTP transport addresses that the 1589 * Transport : peer is bound to. This information is derived 1590 * Address : from the INIT or INIT ACK and is used to 1591 * List : associate an inbound packet with a given 1592 * : association. Normally this information is 1593 * : hashed or keyed for quick lookup and access 1594 * : of the TCB. 1595 * : The list is also initialized with the list 1596 * : of addresses passed with the sctp_connectx() 1597 * : call. 1598 * 1599 * It is a list of SCTP_transport's. 1600 */ 1601 struct list_head transport_addr_list; 1602 1603 /* rwnd 1604 * 1605 * Peer Rwnd : Current calculated value of the peer's rwnd. 1606 */ 1607 __u32 rwnd; 1608 1609 /* transport_count 1610 * 1611 * Peer : A count of the number of peer addresses 1612 * Transport : in the Peer Transport Address List. 1613 * Address : 1614 * Count : 1615 */ 1616 __u16 transport_count; 1617 1618 /* port 1619 * The transport layer port number. 1620 */ 1621 __u16 port; 1622 1623 /* primary_path 1624 * 1625 * Primary : This is the current primary destination 1626 * Path : transport address of the peer endpoint. It 1627 * : may also specify a source transport address 1628 * : on this endpoint. 1629 * 1630 * All of these paths live on transport_addr_list. 1631 * 1632 * At the bakeoffs, we discovered that the intent of 1633 * primaryPath is that it only changes when the ULP 1634 * asks to have it changed. We add the activePath to 1635 * designate the connection we are currently using to 1636 * transmit new data and most control chunks. 1637 */ 1638 struct sctp_transport *primary_path; 1639 1640 /* Cache the primary path address here, when we 1641 * need a an address for msg_name. 1642 */ 1643 union sctp_addr primary_addr; 1644 1645 /* active_path 1646 * The path that we are currently using to 1647 * transmit new data and most control chunks. 1648 */ 1649 struct sctp_transport *active_path; 1650 1651 /* retran_path 1652 * 1653 * RFC2960 6.4 Multi-homed SCTP Endpoints 1654 * ... 1655 * Furthermore, when its peer is multi-homed, an 1656 * endpoint SHOULD try to retransmit a chunk to an 1657 * active destination transport address that is 1658 * different from the last destination address to 1659 * which the DATA chunk was sent. 1660 */ 1661 struct sctp_transport *retran_path; 1662 1663 /* Pointer to last transport I have sent on. */ 1664 struct sctp_transport *last_sent_to; 1665 1666 /* This is the last transport I have received DATA on. */ 1667 struct sctp_transport *last_data_from; 1668 1669 /* 1670 * Mapping An array of bits or bytes indicating which out of 1671 * Array order TSN's have been received (relative to the 1672 * Last Rcvd TSN). If no gaps exist, i.e. no out of 1673 * order packets have been received, this array 1674 * will be set to all zero. This structure may be 1675 * in the form of a circular buffer or bit array. 1676 * 1677 * Last Rcvd : This is the last TSN received in 1678 * TSN : sequence. This value is set initially by 1679 * : taking the peer's Initial TSN, received in 1680 * : the INIT or INIT ACK chunk, and subtracting 1681 * : one from it. 1682 * 1683 * Throughout most of the specification this is called the 1684 * "Cumulative TSN ACK Point". In this case, we 1685 * ignore the advice in 12.2 in favour of the term 1686 * used in the bulk of the text. This value is hidden 1687 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn(). 1688 */ 1689 struct sctp_tsnmap tsn_map; 1690 1691 /* This mask is used to disable sending the ASCONF chunk 1692 * with specified parameter to peer. 1693 */ 1694 __be16 addip_disabled_mask; 1695 1696 /* These are capabilities which our peer advertised. */ 1697 __u8 ecn_capable:1, /* Can peer do ECN? */ 1698 ipv4_address:1, /* Peer understands IPv4 addresses? */ 1699 ipv6_address:1, /* Peer understands IPv6 addresses? */ 1700 hostname_address:1, /* Peer understands DNS addresses? */ 1701 asconf_capable:1, /* Does peer support ADDIP? */ 1702 prsctp_capable:1, /* Can peer do PR-SCTP? */ 1703 reconf_capable:1, /* Can peer do RE-CONFIG? */ 1704 auth_capable:1; /* Is peer doing SCTP-AUTH? */ 1705 1706 /* sack_needed : This flag indicates if the next received 1707 * : packet is to be responded to with a 1708 * : SACK. This is initialized to 0. When a packet 1709 * : is received sack_cnt is incremented. If this value 1710 * : reaches 2 or more, a SACK is sent and the 1711 * : value is reset to 0. Note: This is used only 1712 * : when no DATA chunks are received out of 1713 * : order. When DATA chunks are out of order, 1714 * : SACK's are not delayed (see Section 6). 1715 */ 1716 __u8 sack_needed:1, /* Do we need to sack the peer? */ 1717 sack_generation:1, 1718 zero_window_announced:1; 1719 __u32 sack_cnt; 1720 1721 __u32 adaptation_ind; /* Adaptation Code point. */ 1722 1723 struct sctp_inithdr_host i; 1724 void *cookie; 1725 int cookie_len; 1726 1727 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. 1728 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the 1729 * Initial TSN Value minus 1 1730 */ 1731 __u32 addip_serial; 1732 1733 /* SCTP-AUTH: We need to know pears random number, hmac list 1734 * and authenticated chunk list. All that is part of the 1735 * cookie and these are just pointers to those locations 1736 */ 1737 struct sctp_random_param *peer_random; 1738 struct sctp_chunks_param *peer_chunks; 1739 struct sctp_hmac_algo_param *peer_hmacs; 1740 } peer; 1741 1742 /* State : A state variable indicating what state the 1743 * : association is in, i.e. COOKIE-WAIT, 1744 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING, 1745 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT. 1746 * 1747 * Note: No "CLOSED" state is illustrated since if a 1748 * association is "CLOSED" its TCB SHOULD be removed. 1749 * 1750 * In this implementation we DO have a CLOSED 1751 * state which is used during initiation and shutdown. 1752 * 1753 * State takes values from SCTP_STATE_*. 1754 */ 1755 enum sctp_state state; 1756 1757 /* Overall : The overall association error count. 1758 * Error Count : [Clear this any time I get something.] 1759 */ 1760 int overall_error_count; 1761 1762 /* The cookie life I award for any cookie. */ 1763 ktime_t cookie_life; 1764 1765 /* These are the association's initial, max, and min RTO values. 1766 * These values will be initialized by system defaults, but can 1767 * be modified via the SCTP_RTOINFO socket option. 1768 */ 1769 unsigned long rto_initial; 1770 unsigned long rto_max; 1771 unsigned long rto_min; 1772 1773 /* Maximum number of new data packets that can be sent in a burst. */ 1774 int max_burst; 1775 1776 /* This is the max_retrans value for the association. This value will 1777 * be initialized initialized from system defaults, but can be 1778 * modified by the SCTP_ASSOCINFO socket option. 1779 */ 1780 int max_retrans; 1781 1782 /* This is the partially failed retrans value for the transport 1783 * and will be initialized from the assocs value. This can be 1784 * changed using the SCTP_PEER_ADDR_THLDS socket option 1785 */ 1786 int pf_retrans; 1787 1788 /* Maximum number of times the endpoint will retransmit INIT */ 1789 __u16 max_init_attempts; 1790 1791 /* How many times have we resent an INIT? */ 1792 __u16 init_retries; 1793 1794 /* The largest timeout or RTO value to use in attempting an INIT */ 1795 unsigned long max_init_timeo; 1796 1797 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 1798 * the destination address every heartbeat interval. This value 1799 * will be inherited by all new transports. 1800 */ 1801 unsigned long hbinterval; 1802 1803 /* This is the max_retrans value for new transports in the 1804 * association. 1805 */ 1806 __u16 pathmaxrxt; 1807 1808 __u32 flowlabel; 1809 __u8 dscp; 1810 1811 /* Flag that path mtu update is pending */ 1812 __u8 pmtu_pending; 1813 1814 /* Association : The smallest PMTU discovered for all of the 1815 * PMTU : peer's transport addresses. 1816 */ 1817 __u32 pathmtu; 1818 1819 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 1820 __u32 param_flags; 1821 1822 __u32 sackfreq; 1823 /* SACK delay timeout */ 1824 unsigned long sackdelay; 1825 1826 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES]; 1827 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES]; 1828 1829 /* Transport to which SHUTDOWN chunk was last sent. */ 1830 struct sctp_transport *shutdown_last_sent_to; 1831 1832 /* Transport to which INIT chunk was last sent. */ 1833 struct sctp_transport *init_last_sent_to; 1834 1835 /* How many times have we resent a SHUTDOWN */ 1836 int shutdown_retries; 1837 1838 /* Next TSN : The next TSN number to be assigned to a new 1839 * : DATA chunk. This is sent in the INIT or INIT 1840 * : ACK chunk to the peer and incremented each 1841 * : time a DATA chunk is assigned a TSN 1842 * : (normally just prior to transmit or during 1843 * : fragmentation). 1844 */ 1845 __u32 next_tsn; 1846 1847 /* 1848 * Last Rcvd : This is the last TSN received in sequence. This value 1849 * TSN : is set initially by taking the peer's Initial TSN, 1850 * : received in the INIT or INIT ACK chunk, and 1851 * : subtracting one from it. 1852 * 1853 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point. 1854 */ 1855 1856 __u32 ctsn_ack_point; 1857 1858 /* PR-SCTP Advanced.Peer.Ack.Point */ 1859 __u32 adv_peer_ack_point; 1860 1861 /* Highest TSN that is acknowledged by incoming SACKs. */ 1862 __u32 highest_sacked; 1863 1864 /* TSN marking the fast recovery exit point */ 1865 __u32 fast_recovery_exit; 1866 1867 /* Flag to track the current fast recovery state */ 1868 __u8 fast_recovery; 1869 1870 /* The number of unacknowledged data chunks. Reported through 1871 * the SCTP_STATUS sockopt. 1872 */ 1873 __u16 unack_data; 1874 1875 /* The total number of data chunks that we've had to retransmit 1876 * as the result of a T3 timer expiration 1877 */ 1878 __u32 rtx_data_chunks; 1879 1880 /* This is the association's receive buffer space. This value is used 1881 * to set a_rwnd field in an INIT or a SACK chunk. 1882 */ 1883 __u32 rwnd; 1884 1885 /* This is the last advertised value of rwnd over a SACK chunk. */ 1886 __u32 a_rwnd; 1887 1888 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed 1889 * to slop over a maximum of the association's frag_point. 1890 */ 1891 __u32 rwnd_over; 1892 1893 /* Keeps treack of rwnd pressure. This happens when we have 1894 * a window, but not recevie buffer (i.e small packets). This one 1895 * is releases slowly (1 PMTU at a time ). 1896 */ 1897 __u32 rwnd_press; 1898 1899 /* This is the sndbuf size in use for the association. 1900 * This corresponds to the sndbuf size for the association, 1901 * as specified in the sk->sndbuf. 1902 */ 1903 int sndbuf_used; 1904 1905 /* This is the amount of memory that this association has allocated 1906 * in the receive path at any given time. 1907 */ 1908 atomic_t rmem_alloc; 1909 1910 /* This is the wait queue head for send requests waiting on 1911 * the association sndbuf space. 1912 */ 1913 wait_queue_head_t wait; 1914 1915 /* The message size at which SCTP fragmentation will occur. */ 1916 __u32 frag_point; 1917 __u32 user_frag; 1918 1919 /* Counter used to count INIT errors. */ 1920 int init_err_counter; 1921 1922 /* Count the number of INIT cycles (for doubling timeout). */ 1923 int init_cycle; 1924 1925 /* Default send parameters. */ 1926 __u16 default_stream; 1927 __u16 default_flags; 1928 __u32 default_ppid; 1929 __u32 default_context; 1930 __u32 default_timetolive; 1931 1932 /* Default receive parameters */ 1933 __u32 default_rcv_context; 1934 1935 /* Stream arrays */ 1936 struct sctp_stream stream; 1937 1938 /* All outbound chunks go through this structure. */ 1939 struct sctp_outq outqueue; 1940 1941 /* A smart pipe that will handle reordering and fragmentation, 1942 * as well as handle passing events up to the ULP. 1943 */ 1944 struct sctp_ulpq ulpq; 1945 1946 /* Last TSN that caused an ECNE Chunk to be sent. */ 1947 __u32 last_ecne_tsn; 1948 1949 /* Last TSN that caused a CWR Chunk to be sent. */ 1950 __u32 last_cwr_tsn; 1951 1952 /* How many duplicated TSNs have we seen? */ 1953 int numduptsns; 1954 1955 /* These are to support 1956 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses 1957 * and Enforcement of Flow and Message Limits" 1958 * <draft-ietf-tsvwg-addip-sctp-02.txt> 1959 * or "ADDIP" for short. 1960 */ 1961 1962 1963 1964 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1965 * 1966 * R1) One and only one ASCONF Chunk MAY be in transit and 1967 * unacknowledged at any one time. If a sender, after sending 1968 * an ASCONF chunk, decides it needs to transfer another 1969 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1970 * returns from the previous ASCONF Chunk before sending a 1971 * subsequent ASCONF. Note this restriction binds each side, 1972 * so at any time two ASCONF may be in-transit on any given 1973 * association (one sent from each endpoint). 1974 * 1975 * [This is our one-and-only-one ASCONF in flight. If we do 1976 * not have an ASCONF in flight, this is NULL.] 1977 */ 1978 struct sctp_chunk *addip_last_asconf; 1979 1980 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk. 1981 * 1982 * This is needed to implement itmes E1 - E4 of the updated 1983 * spec. Here is the justification: 1984 * 1985 * Since the peer may bundle multiple ASCONF chunks toward us, 1986 * we now need the ability to cache multiple ACKs. The section 1987 * describes in detail how they are cached and cleaned up. 1988 */ 1989 struct list_head asconf_ack_list; 1990 1991 /* These ASCONF chunks are waiting to be sent. 1992 * 1993 * These chunaks can't be pushed to outqueue until receiving 1994 * ASCONF_ACK for the previous ASCONF indicated by 1995 * addip_last_asconf, so as to guarantee that only one ASCONF 1996 * is in flight at any time. 1997 * 1998 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1999 * 2000 * In defining the ASCONF Chunk transfer procedures, it is 2001 * essential that these transfers MUST NOT cause congestion 2002 * within the network. To achieve this, we place these 2003 * restrictions on the transfer of ASCONF Chunks: 2004 * 2005 * R1) One and only one ASCONF Chunk MAY be in transit and 2006 * unacknowledged at any one time. If a sender, after sending 2007 * an ASCONF chunk, decides it needs to transfer another 2008 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 2009 * returns from the previous ASCONF Chunk before sending a 2010 * subsequent ASCONF. Note this restriction binds each side, 2011 * so at any time two ASCONF may be in-transit on any given 2012 * association (one sent from each endpoint). 2013 * 2014 * 2015 * [I really think this is EXACTLY the sort of intelligence 2016 * which already resides in sctp_outq. Please move this 2017 * queue and its supporting logic down there. --piggy] 2018 */ 2019 struct list_head addip_chunk_list; 2020 2021 /* ADDIP Section 4.1 ASCONF Chunk Procedures 2022 * 2023 * A2) A serial number should be assigned to the Chunk. The 2024 * serial number SHOULD be a monotonically increasing 2025 * number. The serial number SHOULD be initialized at 2026 * the start of the association to the same value as the 2027 * Initial TSN and every time a new ASCONF chunk is created 2028 * it is incremented by one after assigning the serial number 2029 * to the newly created chunk. 2030 * 2031 * ADDIP 2032 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF) 2033 * 2034 * Serial Number : 32 bits (unsigned integer) 2035 * 2036 * This value represents a Serial Number for the ASCONF 2037 * Chunk. The valid range of Serial Number is from 0 to 2038 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0 2039 * after reaching 4294967295. 2040 */ 2041 __u32 addip_serial; 2042 int src_out_of_asoc_ok; 2043 union sctp_addr *asconf_addr_del_pending; 2044 struct sctp_transport *new_transport; 2045 2046 /* SCTP AUTH: list of the endpoint shared keys. These 2047 * keys are provided out of band by the user applicaton 2048 * and can't change during the lifetime of the association 2049 */ 2050 struct list_head endpoint_shared_keys; 2051 2052 /* SCTP AUTH: 2053 * The current generated assocaition shared key (secret) 2054 */ 2055 struct sctp_auth_bytes *asoc_shared_key; 2056 struct sctp_shared_key *shkey; 2057 2058 /* SCTP AUTH: hmac id of the first peer requested algorithm 2059 * that we support. 2060 */ 2061 __u16 default_hmac_id; 2062 2063 __u16 active_key_id; 2064 2065 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */ 2066 temp:1, /* Is it a temporary association? */ 2067 force_delay:1, 2068 intl_enable:1, 2069 prsctp_enable:1, 2070 reconf_enable:1; 2071 2072 __u8 strreset_enable; 2073 __u8 strreset_outstanding; /* request param count on the fly */ 2074 2075 __u32 strreset_outseq; /* Update after receiving response */ 2076 __u32 strreset_inseq; /* Update after receiving request */ 2077 __u32 strreset_result[2]; /* save the results of last 2 responses */ 2078 2079 struct sctp_chunk *strreset_chunk; /* save request chunk */ 2080 2081 struct sctp_priv_assoc_stats stats; 2082 2083 int sent_cnt_removable; 2084 2085 __u16 subscribe; 2086 2087 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 2088 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 2089 2090 struct rcu_head rcu; 2091 }; 2092 2093 2094 /* An eyecatcher for determining if we are really looking at an 2095 * association data structure. 2096 */ 2097 enum { 2098 SCTP_ASSOC_EYECATCHER = 0xa550c123, 2099 }; 2100 2101 /* Recover the outter association structure. */ 2102 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base) 2103 { 2104 struct sctp_association *asoc; 2105 2106 asoc = container_of(base, struct sctp_association, base); 2107 return asoc; 2108 } 2109 2110 /* These are function signatures for manipulating associations. */ 2111 2112 2113 struct sctp_association * 2114 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk, 2115 enum sctp_scope scope, gfp_t gfp); 2116 void sctp_association_free(struct sctp_association *); 2117 void sctp_association_put(struct sctp_association *); 2118 void sctp_association_hold(struct sctp_association *); 2119 2120 struct sctp_transport *sctp_assoc_choose_alter_transport( 2121 struct sctp_association *, struct sctp_transport *); 2122 void sctp_assoc_update_retran_path(struct sctp_association *); 2123 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *, 2124 const union sctp_addr *); 2125 int sctp_assoc_lookup_laddr(struct sctp_association *asoc, 2126 const union sctp_addr *laddr); 2127 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *, 2128 const union sctp_addr *address, 2129 const gfp_t gfp, 2130 const int peer_state); 2131 void sctp_assoc_del_peer(struct sctp_association *asoc, 2132 const union sctp_addr *addr); 2133 void sctp_assoc_rm_peer(struct sctp_association *asoc, 2134 struct sctp_transport *peer); 2135 void sctp_assoc_control_transport(struct sctp_association *asoc, 2136 struct sctp_transport *transport, 2137 enum sctp_transport_cmd command, 2138 sctp_sn_error_t error); 2139 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32); 2140 void sctp_assoc_migrate(struct sctp_association *, struct sock *); 2141 int sctp_assoc_update(struct sctp_association *old, 2142 struct sctp_association *new); 2143 2144 __u32 sctp_association_get_next_tsn(struct sctp_association *); 2145 2146 void sctp_assoc_update_frag_point(struct sctp_association *asoc); 2147 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu); 2148 void sctp_assoc_sync_pmtu(struct sctp_association *asoc); 2149 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int); 2150 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int); 2151 void sctp_assoc_set_primary(struct sctp_association *, 2152 struct sctp_transport *); 2153 void sctp_assoc_del_nonprimary_peers(struct sctp_association *, 2154 struct sctp_transport *); 2155 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, 2156 enum sctp_scope scope, gfp_t gfp); 2157 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *, 2158 struct sctp_cookie*, 2159 gfp_t gfp); 2160 int sctp_assoc_set_id(struct sctp_association *, gfp_t); 2161 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc); 2162 struct sctp_chunk *sctp_assoc_lookup_asconf_ack( 2163 const struct sctp_association *asoc, 2164 __be32 serial); 2165 void sctp_asconf_queue_teardown(struct sctp_association *asoc); 2166 2167 int sctp_cmp_addr_exact(const union sctp_addr *ss1, 2168 const union sctp_addr *ss2); 2169 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc); 2170 2171 /* A convenience structure to parse out SCTP specific CMSGs. */ 2172 struct sctp_cmsgs { 2173 struct sctp_initmsg *init; 2174 struct sctp_sndrcvinfo *srinfo; 2175 struct sctp_sndinfo *sinfo; 2176 struct sctp_prinfo *prinfo; 2177 struct sctp_authinfo *authinfo; 2178 struct msghdr *addrs_msg; 2179 }; 2180 2181 /* Structure for tracking memory objects */ 2182 struct sctp_dbg_objcnt_entry { 2183 char *label; 2184 atomic_t *counter; 2185 }; 2186 2187 #endif /* __sctp_structs_h__ */ 2188