1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* SCTP kernel implementation 3 * (C) Copyright IBM Corp. 2001, 2004 4 * Copyright (c) 1999-2000 Cisco, Inc. 5 * Copyright (c) 1999-2001 Motorola, Inc. 6 * Copyright (c) 2001 Intel Corp. 7 * 8 * This file is part of the SCTP kernel implementation 9 * 10 * Please send any bug reports or fixes you make to the 11 * email addresses: 12 * lksctp developers <linux-sctp@vger.kernel.org> 13 * 14 * Written or modified by: 15 * Randall Stewart <randall@sctp.chicago.il.us> 16 * Ken Morneau <kmorneau@cisco.com> 17 * Qiaobing Xie <qxie1@email.mot.com> 18 * La Monte H.P. Yarroll <piggy@acm.org> 19 * Karl Knutson <karl@athena.chicago.il.us> 20 * Jon Grimm <jgrimm@us.ibm.com> 21 * Xingang Guo <xingang.guo@intel.com> 22 * Hui Huang <hui.huang@nokia.com> 23 * Sridhar Samudrala <sri@us.ibm.com> 24 * Daisy Chang <daisyc@us.ibm.com> 25 * Dajiang Zhang <dajiang.zhang@nokia.com> 26 * Ardelle Fan <ardelle.fan@intel.com> 27 * Ryan Layer <rmlayer@us.ibm.com> 28 * Anup Pemmaiah <pemmaiah@cc.usu.edu> 29 * Kevin Gao <kevin.gao@intel.com> 30 */ 31 32 #ifndef __sctp_structs_h__ 33 #define __sctp_structs_h__ 34 35 #include <crypto/sha2.h> 36 #include <linux/ktime.h> 37 #include <linux/generic-radix-tree.h> 38 #include <linux/rhashtable-types.h> 39 #include <linux/socket.h> /* linux/in.h needs this!! */ 40 #include <linux/in.h> /* We get struct sockaddr_in. */ 41 #include <linux/in6.h> /* We get struct in6_addr */ 42 #include <linux/ipv6.h> 43 #include <asm/param.h> /* We get MAXHOSTNAMELEN. */ 44 #include <linux/atomic.h> /* This gets us atomic counters. */ 45 #include <linux/skbuff.h> /* We need sk_buff_head. */ 46 #include <linux/workqueue.h> /* We need tq_struct. */ 47 #include <linux/sctp.h> /* We need sctp* header structs. */ 48 #include <net/sctp/auth.h> /* We need auth specific structs */ 49 #include <net/ip.h> /* For inet_skb_parm */ 50 51 /* A convenience structure for handling sockaddr structures. 52 * We should wean ourselves off this. 53 */ 54 union sctp_addr { 55 struct sockaddr_inet sa; /* Large enough for both address families */ 56 struct sockaddr_in v4; 57 struct sockaddr_in6 v6; 58 }; 59 60 /* Forward declarations for data structures. */ 61 struct sctp_globals; 62 struct sctp_endpoint; 63 struct sctp_association; 64 struct sctp_transport; 65 struct sctp_packet; 66 struct sctp_chunk; 67 struct sctp_inq; 68 struct sctp_outq; 69 struct sctp_bind_addr; 70 struct sctp_ulpq; 71 struct sctp_ep_common; 72 struct sctp_stream; 73 74 75 #include <net/sctp/tsnmap.h> 76 #include <net/sctp/ulpevent.h> 77 #include <net/sctp/ulpqueue.h> 78 #include <net/sctp/stream_interleave.h> 79 80 /* Structures useful for managing bind/connect. */ 81 82 struct sctp_bind_bucket { 83 unsigned short port; 84 signed char fastreuse; 85 signed char fastreuseport; 86 kuid_t fastuid; 87 struct hlist_node node; 88 struct hlist_head owner; 89 struct net *net; 90 }; 91 92 struct sctp_bind_hashbucket { 93 spinlock_t lock; 94 struct hlist_head chain; 95 }; 96 97 /* Used for hashing all associations. */ 98 struct sctp_hashbucket { 99 rwlock_t lock; 100 struct hlist_head chain; 101 } __attribute__((__aligned__(8))); 102 103 104 /* The SCTP globals structure. */ 105 extern struct sctp_globals { 106 /* This is a list of groups of functions for each address 107 * family that we support. 108 */ 109 struct list_head address_families; 110 111 /* This is the hash of all endpoints. */ 112 struct sctp_hashbucket *ep_hashtable; 113 /* This is the sctp port control hash. */ 114 struct sctp_bind_hashbucket *port_hashtable; 115 /* This is the hash of all transports. */ 116 struct rhltable transport_hashtable; 117 118 /* Sizes of above hashtables. */ 119 int ep_hashsize; 120 int port_hashsize; 121 122 /* Default initialization values to be applied to new associations. */ 123 __u16 max_instreams; 124 __u16 max_outstreams; 125 126 /* Flag to indicate whether computing and verifying checksum 127 * is disabled. */ 128 bool checksum_disable; 129 } sctp_globals; 130 131 #define sctp_max_instreams (sctp_globals.max_instreams) 132 #define sctp_max_outstreams (sctp_globals.max_outstreams) 133 #define sctp_address_families (sctp_globals.address_families) 134 #define sctp_ep_hashsize (sctp_globals.ep_hashsize) 135 #define sctp_ep_hashtable (sctp_globals.ep_hashtable) 136 #define sctp_port_hashsize (sctp_globals.port_hashsize) 137 #define sctp_port_hashtable (sctp_globals.port_hashtable) 138 #define sctp_transport_hashtable (sctp_globals.transport_hashtable) 139 #define sctp_checksum_disable (sctp_globals.checksum_disable) 140 141 /* SCTP Socket type: UDP or TCP style. */ 142 enum sctp_socket_type { 143 SCTP_SOCKET_UDP = 0, 144 SCTP_SOCKET_UDP_HIGH_BANDWIDTH, 145 SCTP_SOCKET_TCP 146 }; 147 148 /* Per socket SCTP information. */ 149 struct sctp_sock { 150 /* inet_sock has to be the first member of sctp_sock */ 151 struct inet_sock inet; 152 /* What kind of a socket is this? */ 153 enum sctp_socket_type type; 154 155 /* PF_ family specific functions. */ 156 struct sctp_pf *pf; 157 158 /* What is our base endpointer? */ 159 struct sctp_endpoint *ep; 160 161 struct sctp_bind_bucket *bind_hash; 162 /* Various Socket Options. */ 163 __u16 default_stream; 164 __u32 default_ppid; 165 __u16 default_flags; 166 __u32 default_context; 167 __u32 default_timetolive; 168 __u32 default_rcv_context; 169 int max_burst; 170 171 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 172 * the destination address every heartbeat interval. This value 173 * will be inherited by all new associations. 174 */ 175 __u32 hbinterval; 176 __u32 probe_interval; 177 178 __be16 udp_port; 179 __be16 encap_port; 180 181 /* This is the max_retrans value for new associations. */ 182 __u16 pathmaxrxt; 183 184 __u32 flowlabel; 185 __u8 dscp; 186 187 __u16 pf_retrans; 188 __u16 ps_retrans; 189 190 /* The initial Path MTU to use for new associations. */ 191 __u32 pathmtu; 192 193 /* The default SACK delay timeout for new associations. */ 194 __u32 sackdelay; 195 __u32 sackfreq; 196 197 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 198 __u32 param_flags; 199 200 __u32 default_ss; 201 202 struct sctp_rtoinfo rtoinfo; 203 struct sctp_paddrparams paddrparam; 204 struct sctp_assocparams assocparams; 205 206 /* 207 * These two structures must be grouped together for the usercopy 208 * whitelist region. 209 */ 210 __u16 subscribe; 211 struct sctp_initmsg initmsg; 212 213 int user_frag; 214 215 __u32 autoclose; 216 __u32 adaptation_ind; 217 __u32 pd_point; 218 __u16 nodelay:1, 219 pf_expose:2, 220 reuse:1, 221 disable_fragments:1, 222 v4mapped:1, 223 frag_interleave:1, 224 recvrcvinfo:1, 225 recvnxtinfo:1, 226 data_ready_signalled:1, 227 cookie_auth_enable:1; 228 229 atomic_t pd_mode; 230 231 /* Receive to here while partial delivery is in effect. */ 232 struct sk_buff_head pd_lobby; 233 234 struct list_head auto_asconf_list; 235 int do_auto_asconf; 236 }; 237 238 #define sctp_sk(ptr) container_of_const(ptr, struct sctp_sock, inet.sk) 239 240 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp) 241 { 242 return (struct sock *)sp; 243 } 244 245 #if IS_ENABLED(CONFIG_IPV6) 246 struct sctp6_sock { 247 struct sctp_sock sctp; 248 struct ipv6_pinfo inet6; 249 }; 250 #endif /* CONFIG_IPV6 */ 251 252 253 /* This is our APPLICATION-SPECIFIC state cookie. 254 * THIS IS NOT DICTATED BY THE SPECIFICATION. 255 */ 256 /* These are the parts of an association which we send in the cookie. 257 * Most of these are straight out of: 258 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB) 259 * 260 */ 261 262 struct sctp_cookie { 263 264 /* My : Tag expected in every inbound packet and sent 265 * Verification: in the INIT or INIT ACK chunk. 266 * Tag : 267 */ 268 __u32 my_vtag; 269 270 /* Peer's : Tag expected in every outbound packet except 271 * Verification: in the INIT chunk. 272 * Tag : 273 */ 274 __u32 peer_vtag; 275 276 /* The rest of these are not from the spec, but really need to 277 * be in the cookie. 278 */ 279 280 /* My Tie Tag : Assist in discovering a restarting association. */ 281 __u32 my_ttag; 282 283 /* Peer's Tie Tag: Assist in discovering a restarting association. */ 284 __u32 peer_ttag; 285 286 /* When does this cookie expire? */ 287 ktime_t expiration; 288 289 /* Number of inbound/outbound streams which are set 290 * and negotiated during the INIT process. 291 */ 292 __u16 sinit_num_ostreams; 293 __u16 sinit_max_instreams; 294 295 /* This is the first sequence number I used. */ 296 __u32 initial_tsn; 297 298 /* This holds the originating address of the INIT packet. */ 299 union sctp_addr peer_addr; 300 301 /* IG Section 2.35.3 302 * Include the source port of the INIT-ACK 303 */ 304 __u16 my_port; 305 306 __u8 prsctp_capable; 307 308 /* Padding for future use */ 309 __u8 padding; 310 311 __u32 adaptation_ind; 312 313 __u8 auth_random[sizeof(struct sctp_paramhdr) + 314 SCTP_AUTH_RANDOM_LENGTH]; 315 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2]; 316 __u8 auth_chunks[sizeof(struct sctp_paramhdr) + SCTP_AUTH_MAX_CHUNKS]; 317 318 /* This is a shim for my peer's INIT packet, followed by 319 * a copy of the raw address list of the association. 320 * The length of the raw address list is saved in the 321 * raw_addr_list_len field, which will be used at the time when 322 * the association TCB is re-constructed from the cookie. 323 */ 324 __u32 raw_addr_list_len; 325 /* struct sctp_init_chunk peer_init[]; */ 326 }; 327 328 329 /* The format of our cookie that we send to our peer. */ 330 struct sctp_signed_cookie { 331 __u8 mac[SCTP_COOKIE_MAC_SIZE]; 332 __u32 __pad; /* force sctp_cookie alignment to 64 bits */ 333 struct sctp_cookie c; 334 } __packed; 335 336 /* This is another convenience type to allocate memory for address 337 * params for the maximum size and pass such structures around 338 * internally. 339 */ 340 union sctp_addr_param { 341 struct sctp_paramhdr p; 342 struct sctp_ipv4addr_param v4; 343 struct sctp_ipv6addr_param v6; 344 }; 345 346 /* A convenience type to allow walking through the various 347 * parameters and avoid casting all over the place. 348 */ 349 union sctp_params { 350 void *v; 351 struct sctp_paramhdr *p; 352 struct sctp_cookie_preserve_param *life; 353 struct sctp_hostname_param *dns; 354 struct sctp_cookie_param *cookie; 355 struct sctp_supported_addrs_param *sat; 356 struct sctp_ipv4addr_param *v4; 357 struct sctp_ipv6addr_param *v6; 358 union sctp_addr_param *addr; 359 struct sctp_adaptation_ind_param *aind; 360 struct sctp_supported_ext_param *ext; 361 struct sctp_random_param *random; 362 struct sctp_chunks_param *chunks; 363 struct sctp_hmac_algo_param *hmac_algo; 364 struct sctp_addip_param *addip; 365 }; 366 367 /* RFC 2960. Section 3.3.5 Heartbeat. 368 * Heartbeat Information: variable length 369 * The Sender-specific Heartbeat Info field should normally include 370 * information about the sender's current time when this HEARTBEAT 371 * chunk is sent and the destination transport address to which this 372 * HEARTBEAT is sent (see Section 8.3). 373 */ 374 struct sctp_sender_hb_info { 375 struct sctp_paramhdr param_hdr; 376 union sctp_addr daddr; 377 unsigned long sent_at; 378 __u64 hb_nonce; 379 __u32 probe_size; 380 }; 381 382 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt, 383 gfp_t gfp); 384 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid); 385 void sctp_stream_free(struct sctp_stream *stream); 386 void sctp_stream_clear(struct sctp_stream *stream); 387 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new); 388 389 /* What is the current SSN number for this stream? */ 390 #define sctp_ssn_peek(stream, type, sid) \ 391 (sctp_stream_##type((stream), (sid))->ssn) 392 393 /* Return the next SSN number for this stream. */ 394 #define sctp_ssn_next(stream, type, sid) \ 395 (sctp_stream_##type((stream), (sid))->ssn++) 396 397 /* Skip over this ssn and all below. */ 398 #define sctp_ssn_skip(stream, type, sid, ssn) \ 399 (sctp_stream_##type((stream), (sid))->ssn = ssn + 1) 400 401 /* What is the current MID number for this stream? */ 402 #define sctp_mid_peek(stream, type, sid) \ 403 (sctp_stream_##type((stream), (sid))->mid) 404 405 /* Return the next MID number for this stream. */ 406 #define sctp_mid_next(stream, type, sid) \ 407 (sctp_stream_##type((stream), (sid))->mid++) 408 409 /* Skip over this mid and all below. */ 410 #define sctp_mid_skip(stream, type, sid, mid) \ 411 (sctp_stream_##type((stream), (sid))->mid = mid + 1) 412 413 /* What is the current MID_uo number for this stream? */ 414 #define sctp_mid_uo_peek(stream, type, sid) \ 415 (sctp_stream_##type((stream), (sid))->mid_uo) 416 417 /* Return the next MID_uo number for this stream. */ 418 #define sctp_mid_uo_next(stream, type, sid) \ 419 (sctp_stream_##type((stream), (sid))->mid_uo++) 420 421 /* 422 * Pointers to address related SCTP functions. 423 * (i.e. things that depend on the address family.) 424 */ 425 struct sctp_af { 426 int (*sctp_xmit) (struct sk_buff *skb, 427 struct sctp_transport *); 428 int (*setsockopt) (struct sock *sk, 429 int level, 430 int optname, 431 sockptr_t optval, 432 unsigned int optlen); 433 int (*getsockopt) (struct sock *sk, 434 int level, 435 int optname, 436 char __user *optval, 437 int __user *optlen); 438 void (*get_dst) (struct sctp_transport *t, 439 union sctp_addr *saddr, 440 struct flowi *fl, 441 struct sock *sk); 442 void (*get_saddr) (struct sctp_sock *sk, 443 struct sctp_transport *t, 444 struct flowi *fl); 445 void (*copy_addrlist) (struct list_head *, 446 struct net_device *); 447 int (*cmp_addr) (const union sctp_addr *addr1, 448 const union sctp_addr *addr2); 449 void (*addr_copy) (union sctp_addr *dst, 450 union sctp_addr *src); 451 void (*from_skb) (union sctp_addr *, 452 struct sk_buff *skb, 453 int saddr); 454 void (*from_sk) (union sctp_addr *, 455 struct sock *sk); 456 bool (*from_addr_param) (union sctp_addr *, 457 union sctp_addr_param *, 458 __be16 port, int iif); 459 int (*to_addr_param) (const union sctp_addr *, 460 union sctp_addr_param *); 461 int (*addr_valid) (union sctp_addr *, 462 struct sctp_sock *, 463 const struct sk_buff *); 464 enum sctp_scope (*scope)(union sctp_addr *); 465 void (*inaddr_any) (union sctp_addr *, __be16); 466 int (*is_any) (const union sctp_addr *); 467 int (*available) (union sctp_addr *, 468 struct sctp_sock *); 469 int (*skb_iif) (const struct sk_buff *sk); 470 int (*skb_sdif)(const struct sk_buff *sk); 471 int (*is_ce) (const struct sk_buff *sk); 472 void (*seq_dump_addr)(struct seq_file *seq, 473 union sctp_addr *addr); 474 void (*ecn_capable)(struct sock *sk); 475 __u16 net_header_len; 476 int sockaddr_len; 477 int (*ip_options_len)(struct sock *sk); 478 sa_family_t sa_family; 479 struct list_head list; 480 }; 481 482 struct sctp_af *sctp_get_af_specific(sa_family_t); 483 int sctp_register_af(struct sctp_af *); 484 485 /* Protocol family functions. */ 486 struct sctp_pf { 487 void (*event_msgname)(struct sctp_ulpevent *, char *, int *); 488 void (*skb_msgname) (struct sk_buff *, char *, int *); 489 int (*af_supported) (sa_family_t, struct sctp_sock *); 490 int (*cmp_addr) (const union sctp_addr *, 491 const union sctp_addr *, 492 struct sctp_sock *); 493 int (*bind_verify) (struct sctp_sock *, union sctp_addr *); 494 int (*send_verify) (struct sctp_sock *, union sctp_addr *); 495 int (*supported_addrs)(const struct sctp_sock *, __be16 *); 496 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr); 497 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk); 498 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk); 499 void (*copy_ip_options)(struct sock *sk, struct sock *newsk); 500 struct sctp_af *af; 501 }; 502 503 504 /* Structure to track chunk fragments that have been acked, but peer 505 * fragments of the same message have not. 506 */ 507 struct sctp_datamsg { 508 /* Chunks waiting to be submitted to lower layer. */ 509 struct list_head chunks; 510 /* Reference counting. */ 511 refcount_t refcnt; 512 /* When is this message no longer interesting to the peer? */ 513 unsigned long expires_at; 514 /* Did the message fail to send? */ 515 int send_error; 516 u8 send_failed:1, 517 can_delay:1, /* should this message be Nagle delayed */ 518 abandoned:1; /* should this message be abandoned */ 519 }; 520 521 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *, 522 struct sctp_sndrcvinfo *, 523 struct iov_iter *); 524 void sctp_datamsg_free(struct sctp_datamsg *); 525 void sctp_datamsg_put(struct sctp_datamsg *); 526 void sctp_chunk_fail(struct sctp_chunk *, int error); 527 int sctp_chunk_abandoned(struct sctp_chunk *); 528 529 /* RFC2960 1.4 Key Terms 530 * 531 * o Chunk: A unit of information within an SCTP packet, consisting of 532 * a chunk header and chunk-specific content. 533 * 534 * As a matter of convenience, we remember the SCTP common header for 535 * each chunk as well as a few other header pointers... 536 */ 537 struct sctp_chunk { 538 struct list_head list; 539 540 refcount_t refcnt; 541 542 /* How many times this chunk have been sent, for prsctp RTX policy */ 543 int sent_count; 544 545 union { 546 /* This is our link to the per-transport transmitted list. */ 547 struct list_head transmitted_list; 548 /* List in specific stream outq */ 549 struct list_head stream_list; 550 }; 551 552 /* This field is used by chunks that hold fragmented data. 553 * For the first fragment this is the list that holds the rest of 554 * fragments. For the remaining fragments, this is the link to the 555 * frag_list maintained in the first fragment. 556 */ 557 struct list_head frag_list; 558 559 /* This points to the sk_buff containing the actual data. */ 560 struct sk_buff *skb; 561 562 union { 563 /* In case of GSO packets, this will store the head one */ 564 struct sk_buff *head_skb; 565 /* In case of auth enabled, this will point to the shkey */ 566 struct sctp_shared_key *shkey; 567 }; 568 569 /* These are the SCTP headers by reverse order in a packet. 570 * Note that some of these may happen more than once. In that 571 * case, we point at the "current" one, whatever that means 572 * for that level of header. 573 */ 574 575 /* We point this at the FIRST TLV parameter to chunk_hdr. */ 576 union sctp_params param_hdr; 577 union { 578 __u8 *v; 579 struct sctp_datahdr *data_hdr; 580 struct sctp_inithdr *init_hdr; 581 struct sctp_sackhdr *sack_hdr; 582 struct sctp_heartbeathdr *hb_hdr; 583 struct sctp_sender_hb_info *hbs_hdr; 584 struct sctp_shutdownhdr *shutdown_hdr; 585 struct sctp_signed_cookie *cookie_hdr; 586 struct sctp_ecnehdr *ecne_hdr; 587 struct sctp_cwrhdr *ecn_cwr_hdr; 588 struct sctp_errhdr *err_hdr; 589 struct sctp_addiphdr *addip_hdr; 590 struct sctp_fwdtsn_hdr *fwdtsn_hdr; 591 struct sctp_authhdr *auth_hdr; 592 struct sctp_idatahdr *idata_hdr; 593 struct sctp_ifwdtsn_hdr *ifwdtsn_hdr; 594 } subh; 595 596 __u8 *chunk_end; 597 598 struct sctp_chunkhdr *chunk_hdr; 599 struct sctphdr *sctp_hdr; 600 601 /* This needs to be recoverable for SCTP_SEND_FAILED events. */ 602 struct sctp_sndrcvinfo sinfo; 603 604 /* Which association does this belong to? */ 605 struct sctp_association *asoc; 606 607 /* What endpoint received this chunk? */ 608 struct sctp_ep_common *rcvr; 609 610 /* We fill this in if we are calculating RTT. */ 611 unsigned long sent_at; 612 613 /* What is the origin IP address for this chunk? */ 614 union sctp_addr source; 615 /* Destination address for this chunk. */ 616 union sctp_addr dest; 617 618 /* For outbound message, track all fragments for SEND_FAILED. */ 619 struct sctp_datamsg *msg; 620 621 /* For an inbound chunk, this tells us where it came from. 622 * For an outbound chunk, it tells us where we'd like it to 623 * go. It is NULL if we have no preference. 624 */ 625 struct sctp_transport *transport; 626 627 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO 628 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH 629 * spec violates the principle premis that all chunks are processed 630 * in order. 631 */ 632 struct sk_buff *auth_chunk; 633 634 #define SCTP_CAN_FRTX 0x0 635 #define SCTP_NEED_FRTX 0x1 636 #define SCTP_DONT_FRTX 0x2 637 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */ 638 has_tsn:1, /* Does this chunk have a TSN yet? */ 639 has_ssn:1, /* Does this chunk have a SSN yet? */ 640 #define has_mid has_ssn 641 singleton:1, /* Only chunk in the packet? */ 642 end_of_packet:1, /* Last chunk in the packet? */ 643 ecn_ce_done:1, /* Have we processed the ECN CE bit? */ 644 pdiscard:1, /* Discard the whole packet now? */ 645 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */ 646 data_accepted:1, /* At least 1 chunk accepted */ 647 auth:1, /* IN: was auth'ed | OUT: needs auth */ 648 has_asconf:1, /* IN: have seen an asconf before */ 649 pmtu_probe:1, /* Used by PLPMTUD, can be set in s HB chunk */ 650 tsn_missing_report:2, /* Data chunk missing counter. */ 651 fast_retransmit:2; /* Is this chunk fast retransmitted? */ 652 }; 653 654 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1) 655 void sctp_chunk_hold(struct sctp_chunk *); 656 void sctp_chunk_put(struct sctp_chunk *); 657 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len, 658 struct iov_iter *from); 659 void sctp_chunk_free(struct sctp_chunk *); 660 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data); 661 struct sctp_chunk *sctp_chunkify(struct sk_buff *, 662 const struct sctp_association *, 663 struct sock *, gfp_t gfp); 664 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *, 665 union sctp_addr *); 666 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk); 667 668 static inline __u16 sctp_chunk_stream_no(struct sctp_chunk *ch) 669 { 670 return ntohs(ch->subh.data_hdr->stream); 671 } 672 673 enum { 674 SCTP_ADDR_NEW, /* new address added to assoc/ep */ 675 SCTP_ADDR_SRC, /* address can be used as source */ 676 SCTP_ADDR_DEL, /* address about to be deleted */ 677 }; 678 679 /* This is a structure for holding either an IPv6 or an IPv4 address. */ 680 struct sctp_sockaddr_entry { 681 struct list_head list; 682 struct rcu_head rcu; 683 union sctp_addr a; 684 __u8 state; 685 __u8 valid; 686 }; 687 688 #define SCTP_ADDRESS_TICK_DELAY 500 689 690 /* This structure holds lists of chunks as we are assembling for 691 * transmission. 692 */ 693 struct sctp_packet { 694 /* These are the SCTP header values (host order) for the packet. */ 695 __u16 source_port; 696 __u16 destination_port; 697 __u32 vtag; 698 699 /* This contains the payload chunks. */ 700 struct list_head chunk_list; 701 702 /* This is the overhead of the sctp and ip headers. */ 703 size_t overhead; 704 /* This is the total size of all chunks INCLUDING padding. */ 705 size_t size; 706 /* This is the maximum size this packet may have */ 707 size_t max_size; 708 709 /* The packet is destined for this transport address. 710 * The function we finally use to pass down to the next lower 711 * layer lives in the transport structure. 712 */ 713 struct sctp_transport *transport; 714 715 /* pointer to the auth chunk for this packet */ 716 struct sctp_chunk *auth; 717 718 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */ 719 has_sack:1, /* This packet contains a SACK chunk. */ 720 has_auth:1, /* This packet contains an AUTH chunk */ 721 has_data:1, /* This packet contains at least 1 DATA chunk */ 722 ipfragok:1; /* So let ip fragment this packet */ 723 }; 724 725 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *, 726 __u16 sport, __u16 dport); 727 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int); 728 enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet, 729 struct sctp_chunk *chunk, 730 int one_packet, gfp_t gfp); 731 enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet, 732 struct sctp_chunk *chunk); 733 int sctp_packet_transmit(struct sctp_packet *, gfp_t); 734 void sctp_packet_free(struct sctp_packet *); 735 736 static inline int sctp_packet_empty(struct sctp_packet *packet) 737 { 738 return packet->size == packet->overhead; 739 } 740 741 /* This represents a remote transport address. 742 * For local transport addresses, we just use union sctp_addr. 743 * 744 * RFC2960 Section 1.4 Key Terms 745 * 746 * o Transport address: A Transport Address is traditionally defined 747 * by Network Layer address, Transport Layer protocol and Transport 748 * Layer port number. In the case of SCTP running over IP, a 749 * transport address is defined by the combination of an IP address 750 * and an SCTP port number (where SCTP is the Transport protocol). 751 * 752 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control 753 * 754 * o The sender keeps a separate congestion control parameter set for 755 * each of the destination addresses it can send to (not each 756 * source-destination pair but for each destination). The parameters 757 * should decay if the address is not used for a long enough time 758 * period. 759 * 760 */ 761 struct sctp_transport { 762 /* A list of transports. */ 763 struct list_head transports; 764 struct rhlist_head node; 765 766 /* Reference counting. */ 767 refcount_t refcnt; 768 __u32 dead:1, 769 /* RTO-Pending : A flag used to track if one of the DATA 770 * chunks sent to this address is currently being 771 * used to compute a RTT. If this flag is 0, 772 * the next DATA chunk sent to this destination 773 * should be used to compute a RTT and this flag 774 * should be set. Every time the RTT 775 * calculation completes (i.e. the DATA chunk 776 * is SACK'd) clear this flag. 777 */ 778 rto_pending:1, 779 780 /* 781 * hb_sent : a flag that signals that we have a pending 782 * heartbeat. 783 */ 784 hb_sent:1, 785 786 /* Is the Path MTU update pending on this transport */ 787 pmtu_pending:1, 788 789 dst_pending_confirm:1, /* need to confirm neighbour */ 790 791 /* Has this transport moved the ctsn since we last sacked */ 792 sack_generation:1; 793 u32 dst_cookie; 794 795 struct flowi fl; 796 797 /* This is the peer's IP address and port. */ 798 union sctp_addr ipaddr; 799 800 /* These are the functions we call to handle LLP stuff. */ 801 struct sctp_af *af_specific; 802 803 /* Which association do we belong to? */ 804 struct sctp_association *asoc; 805 806 /* RFC2960 807 * 808 * 12.3 Per Transport Address Data 809 * 810 * For each destination transport address in the peer's 811 * address list derived from the INIT or INIT ACK chunk, a 812 * number of data elements needs to be maintained including: 813 */ 814 /* RTO : The current retransmission timeout value. */ 815 unsigned long rto; 816 817 __u32 rtt; /* This is the most recent RTT. */ 818 819 /* RTTVAR : The current RTT variation. */ 820 __u32 rttvar; 821 822 /* SRTT : The current smoothed round trip time. */ 823 __u32 srtt; 824 825 /* 826 * These are the congestion stats. 827 */ 828 /* cwnd : The current congestion window. */ 829 __u32 cwnd; /* This is the actual cwnd. */ 830 831 /* ssthresh : The current slow start threshold value. */ 832 __u32 ssthresh; 833 834 /* partial : The tracking method for increase of cwnd when in 835 * bytes acked : congestion avoidance mode (see Section 6.2.2) 836 */ 837 __u32 partial_bytes_acked; 838 839 /* Data that has been sent, but not acknowledged. */ 840 __u32 flight_size; 841 842 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */ 843 844 /* Destination */ 845 struct dst_entry *dst; 846 /* Source address. */ 847 union sctp_addr saddr; 848 849 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 850 * the destination address every heartbeat interval. 851 */ 852 unsigned long hbinterval; 853 unsigned long probe_interval; 854 855 /* SACK delay timeout */ 856 unsigned long sackdelay; 857 __u32 sackfreq; 858 859 atomic_t mtu_info; 860 861 /* When was the last time that we heard from this transport? We use 862 * this to pick new active and retran paths. 863 */ 864 ktime_t last_time_heard; 865 866 /* When was the last time that we sent a chunk using this 867 * transport? We use this to check for idle transports 868 */ 869 unsigned long last_time_sent; 870 871 /* Last time(in jiffies) when cwnd is reduced due to the congestion 872 * indication based on ECNE chunk. 873 */ 874 unsigned long last_time_ecne_reduced; 875 876 __be16 encap_port; 877 878 /* This is the max_retrans value for the transport and will 879 * be initialized from the assocs value. This can be changed 880 * using the SCTP_SET_PEER_ADDR_PARAMS socket option. 881 */ 882 __u16 pathmaxrxt; 883 884 __u32 flowlabel; 885 __u8 dscp; 886 887 /* This is the partially failed retrans value for the transport 888 * and will be initialized from the assocs value. This can be changed 889 * using the SCTP_PEER_ADDR_THLDS socket option 890 */ 891 __u16 pf_retrans; 892 /* Used for primary path switchover. */ 893 __u16 ps_retrans; 894 /* PMTU : The current known path MTU. */ 895 __u32 pathmtu; 896 897 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 898 __u32 param_flags; 899 900 /* The number of times INIT has been sent on this transport. */ 901 int init_sent_count; 902 903 /* state : The current state of this destination, 904 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN. 905 */ 906 int state; 907 908 /* These are the error stats for this destination. */ 909 910 /* Error count : The current error count for this destination. */ 911 unsigned short error_count; 912 913 /* Per : A timer used by each destination. 914 * Destination : 915 * Timer : 916 * 917 * [Everywhere else in the text this is called T3-rtx. -ed] 918 */ 919 struct timer_list T3_rtx_timer; 920 921 /* Heartbeat timer is per destination. */ 922 struct timer_list hb_timer; 923 924 /* Timer to handle ICMP proto unreachable envets */ 925 struct timer_list proto_unreach_timer; 926 927 /* Timer to handler reconf chunk rtx */ 928 struct timer_list reconf_timer; 929 930 /* Timer to send a probe HB packet for PLPMTUD */ 931 struct timer_list probe_timer; 932 933 /* Since we're using per-destination retransmission timers 934 * (see above), we're also using per-destination "transmitted" 935 * queues. This probably ought to be a private struct 936 * accessible only within the outqueue, but it's not, yet. 937 */ 938 struct list_head transmitted; 939 940 /* We build bundle-able packets for this transport here. */ 941 struct sctp_packet packet; 942 943 /* This is the list of transports that have chunks to send. */ 944 struct list_head send_ready; 945 946 /* State information saved for SFR_CACC algorithm. The key 947 * idea in SFR_CACC is to maintain state at the sender on a 948 * per-destination basis when a changeover happens. 949 * char changeover_active; 950 * char cycling_changeover; 951 * __u32 next_tsn_at_change; 952 * char cacc_saw_newack; 953 */ 954 struct { 955 /* An unsigned integer, which stores the next TSN to be 956 * used by the sender, at the moment of changeover. 957 */ 958 __u32 next_tsn_at_change; 959 960 /* A flag which indicates the occurrence of a changeover */ 961 char changeover_active; 962 963 /* A flag which indicates whether the change of primary is 964 * the first switch to this destination address during an 965 * active switch. 966 */ 967 char cycling_changeover; 968 969 /* A temporary flag, which is used during the processing of 970 * a SACK to estimate the causative TSN(s)'s group. 971 */ 972 char cacc_saw_newack; 973 } cacc; 974 975 struct { 976 __u16 pmtu; 977 __u16 probe_size; 978 __u16 probe_high; 979 __u8 probe_count; 980 __u8 state; 981 } pl; /* plpmtud related */ 982 983 /* 64-bit random number sent with heartbeat. */ 984 __u64 hb_nonce; 985 986 struct rcu_head rcu; 987 }; 988 989 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *, 990 gfp_t); 991 void sctp_transport_set_owner(struct sctp_transport *, 992 struct sctp_association *); 993 void sctp_transport_route(struct sctp_transport *, union sctp_addr *, 994 struct sctp_sock *); 995 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk); 996 void sctp_transport_free(struct sctp_transport *); 997 void sctp_transport_reset_t3_rtx(struct sctp_transport *); 998 void sctp_transport_reset_hb_timer(struct sctp_transport *); 999 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport); 1000 void sctp_transport_reset_probe_timer(struct sctp_transport *transport); 1001 void sctp_transport_reset_raise_timer(struct sctp_transport *transport); 1002 int sctp_transport_hold(struct sctp_transport *); 1003 void sctp_transport_put(struct sctp_transport *); 1004 void sctp_transport_update_rto(struct sctp_transport *, __u32); 1005 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32); 1006 void sctp_transport_lower_cwnd(struct sctp_transport *t, 1007 enum sctp_lower_cwnd reason); 1008 void sctp_transport_burst_limited(struct sctp_transport *); 1009 void sctp_transport_burst_reset(struct sctp_transport *); 1010 unsigned long sctp_transport_timeout(struct sctp_transport *); 1011 void sctp_transport_reset(struct sctp_transport *t); 1012 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu); 1013 void sctp_transport_immediate_rtx(struct sctp_transport *); 1014 void sctp_transport_dst_release(struct sctp_transport *t); 1015 void sctp_transport_dst_confirm(struct sctp_transport *t); 1016 void sctp_transport_pl_send(struct sctp_transport *t); 1017 bool sctp_transport_pl_recv(struct sctp_transport *t); 1018 1019 1020 /* This is the structure we use to queue packets as they come into 1021 * SCTP. We write packets to it and read chunks from it. 1022 */ 1023 struct sctp_inq { 1024 /* This is actually a queue of sctp_chunk each 1025 * containing a partially decoded packet. 1026 */ 1027 struct list_head in_chunk_list; 1028 /* This is the packet which is currently off the in queue and is 1029 * being worked on through the inbound chunk processing. 1030 */ 1031 struct sctp_chunk *in_progress; 1032 1033 /* This is the delayed task to finish delivering inbound 1034 * messages. 1035 */ 1036 struct work_struct immediate; 1037 }; 1038 1039 void sctp_inq_init(struct sctp_inq *); 1040 void sctp_inq_free(struct sctp_inq *); 1041 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet); 1042 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *); 1043 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *); 1044 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t); 1045 1046 /* This is the structure we use to hold outbound chunks. You push 1047 * chunks in and they automatically pop out the other end as bundled 1048 * packets (it calls (*output_handler)()). 1049 * 1050 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1, 1051 * and 8.2 of the v13 draft. 1052 * 1053 * It handles retransmissions. The connection to the timeout portion 1054 * of the state machine is through sctp_..._timeout() and timeout_handler. 1055 * 1056 * If you feed it SACKs, it will eat them. 1057 * 1058 * If you give it big chunks, it will fragment them. 1059 * 1060 * It assigns TSN's to data chunks. This happens at the last possible 1061 * instant before transmission. 1062 * 1063 * When free()'d, it empties itself out via output_handler(). 1064 */ 1065 struct sctp_outq { 1066 struct sctp_association *asoc; 1067 1068 /* Data pending that has never been transmitted. */ 1069 struct list_head out_chunk_list; 1070 1071 /* Stream scheduler being used */ 1072 const struct sctp_sched_ops *sched; 1073 1074 unsigned int out_qlen; /* Total length of queued data chunks. */ 1075 1076 /* Error of send failed, may used in SCTP_SEND_FAILED event. */ 1077 unsigned int error; 1078 1079 /* These are control chunks we want to send. */ 1080 struct list_head control_chunk_list; 1081 1082 /* These are chunks that have been sacked but are above the 1083 * CTSN, or cumulative tsn ack point. 1084 */ 1085 struct list_head sacked; 1086 1087 /* Put chunks on this list to schedule them for 1088 * retransmission. 1089 */ 1090 struct list_head retransmit; 1091 1092 /* Put chunks on this list to save them for FWD TSN processing as 1093 * they were abandoned. 1094 */ 1095 struct list_head abandoned; 1096 1097 /* How many unackd bytes do we have in-flight? */ 1098 __u32 outstanding_bytes; 1099 1100 /* Are we doing fast-rtx on this queue */ 1101 char fast_rtx; 1102 1103 /* Corked? */ 1104 char cork; 1105 }; 1106 1107 void sctp_outq_init(struct sctp_association *, struct sctp_outq *); 1108 void sctp_outq_teardown(struct sctp_outq *); 1109 void sctp_outq_free(struct sctp_outq*); 1110 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t); 1111 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *); 1112 int sctp_outq_is_empty(const struct sctp_outq *); 1113 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport, 1114 enum sctp_retransmit_reason reason); 1115 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8); 1116 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp); 1117 void sctp_prsctp_prune(struct sctp_association *asoc, 1118 struct sctp_sndrcvinfo *sinfo, int msg_len); 1119 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn); 1120 /* Uncork and flush an outqueue. */ 1121 static inline void sctp_outq_cork(struct sctp_outq *q) 1122 { 1123 q->cork = 1; 1124 } 1125 1126 /* SCTP skb control block. 1127 * sctp_input_cb is currently used on rx and sock rx queue 1128 */ 1129 struct sctp_input_cb { 1130 union { 1131 struct inet_skb_parm h4; 1132 #if IS_ENABLED(CONFIG_IPV6) 1133 struct inet6_skb_parm h6; 1134 #endif 1135 } header; 1136 struct sctp_chunk *chunk; 1137 struct sctp_af *af; 1138 __be16 encap_port; 1139 }; 1140 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0])) 1141 1142 struct sctp_output_cb { 1143 struct sk_buff *last; 1144 }; 1145 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0])) 1146 1147 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb) 1148 { 1149 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; 1150 1151 return chunk->head_skb ? : skb; 1152 } 1153 1154 /* These bind address data fields common between endpoints and associations */ 1155 struct sctp_bind_addr { 1156 1157 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1158 * 1159 * SCTP Port: The local SCTP port number the endpoint is 1160 * bound to. 1161 */ 1162 __u16 port; 1163 1164 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1165 * 1166 * Address List: The list of IP addresses that this instance 1167 * has bound. This information is passed to one's 1168 * peer(s) in INIT and INIT ACK chunks. 1169 */ 1170 struct list_head address_list; 1171 }; 1172 1173 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port); 1174 void sctp_bind_addr_free(struct sctp_bind_addr *); 1175 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest, 1176 const struct sctp_bind_addr *src, 1177 enum sctp_scope scope, gfp_t gfp, 1178 int flags); 1179 int sctp_bind_addr_dup(struct sctp_bind_addr *dest, 1180 const struct sctp_bind_addr *src, 1181 gfp_t gfp); 1182 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *, 1183 int new_size, __u8 addr_state, gfp_t gfp); 1184 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *); 1185 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *, 1186 struct sctp_sock *); 1187 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *, 1188 struct sctp_sock *, struct sctp_sock *); 1189 int sctp_bind_addr_state(const struct sctp_bind_addr *bp, 1190 const union sctp_addr *addr); 1191 int sctp_bind_addrs_check(struct sctp_sock *sp, 1192 struct sctp_sock *sp2, int cnt2); 1193 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp, 1194 const union sctp_addr *addrs, 1195 int addrcnt, 1196 struct sctp_sock *opt); 1197 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp, 1198 int *addrs_len, 1199 gfp_t gfp); 1200 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len, 1201 __u16 port, gfp_t gfp); 1202 1203 enum sctp_scope sctp_scope(const union sctp_addr *addr); 1204 int sctp_in_scope(struct net *net, const union sctp_addr *addr, 1205 const enum sctp_scope scope); 1206 int sctp_is_any(struct sock *sk, const union sctp_addr *addr); 1207 int sctp_is_ep_boundall(struct sock *sk); 1208 1209 1210 /* What type of endpoint? */ 1211 enum sctp_endpoint_type { 1212 SCTP_EP_TYPE_SOCKET, 1213 SCTP_EP_TYPE_ASSOCIATION, 1214 }; 1215 1216 /* 1217 * A common base class to bridge the implementation view of a 1218 * socket (usually listening) endpoint versus an association's 1219 * local endpoint. 1220 * This common structure is useful for several purposes: 1221 * 1) Common interface for lookup routines. 1222 * a) Subfunctions work for either endpoint or association 1223 * b) Single interface to lookup allows hiding the lookup lock rather 1224 * than acquiring it externally. 1225 * 2) Common interface for the inbound chunk handling/state machine. 1226 * 3) Common object handling routines for reference counting, etc. 1227 * 4) Disentangle association lookup from endpoint lookup, where we 1228 * do not have to find our endpoint to find our association. 1229 * 1230 */ 1231 1232 struct sctp_ep_common { 1233 /* Runtime type information. What kind of endpoint is this? */ 1234 enum sctp_endpoint_type type; 1235 1236 /* Some fields to help us manage this object. 1237 * refcnt - Reference count access to this object. 1238 * dead - Do not attempt to use this object. 1239 */ 1240 refcount_t refcnt; 1241 bool dead; 1242 1243 /* What socket does this endpoint belong to? */ 1244 struct sock *sk; 1245 1246 /* Cache netns and it won't change once set */ 1247 struct net *net; 1248 1249 /* This is where we receive inbound chunks. */ 1250 struct sctp_inq inqueue; 1251 1252 /* This substructure includes the defining parameters of the 1253 * endpoint: 1254 * bind_addr.port is our shared port number. 1255 * bind_addr.address_list is our set of local IP addresses. 1256 */ 1257 struct sctp_bind_addr bind_addr; 1258 }; 1259 1260 1261 /* RFC Section 1.4 Key Terms 1262 * 1263 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a 1264 * multi-homed host, an SCTP endpoint is represented to its peers as a 1265 * combination of a set of eligible destination transport addresses to 1266 * which SCTP packets can be sent and a set of eligible source 1267 * transport addresses from which SCTP packets can be received. 1268 * All transport addresses used by an SCTP endpoint must use the 1269 * same port number, but can use multiple IP addresses. A transport 1270 * address used by an SCTP endpoint must not be used by another 1271 * SCTP endpoint. In other words, a transport address is unique 1272 * to an SCTP endpoint. 1273 * 1274 * From an implementation perspective, each socket has one of these. 1275 * A TCP-style socket will have exactly one association on one of 1276 * these. An UDP-style socket will have multiple associations hanging 1277 * off one of these. 1278 */ 1279 1280 struct sctp_endpoint { 1281 /* Common substructure for endpoint and association. */ 1282 struct sctp_ep_common base; 1283 1284 /* Fields to help us manage our entries in the hash tables. */ 1285 struct hlist_node node; 1286 int hashent; 1287 1288 /* Associations: A list of current associations and mappings 1289 * to the data consumers for each association. This 1290 * may be in the form of a hash table or other 1291 * implementation dependent structure. The data 1292 * consumers may be process identification 1293 * information such as file descriptors, named pipe 1294 * pointer, or table pointers dependent on how SCTP 1295 * is implemented. 1296 */ 1297 /* This is really a list of struct sctp_association entries. */ 1298 struct list_head asocs; 1299 1300 /* Cookie authentication key used by this endpoint */ 1301 struct hmac_sha256_key cookie_auth_key; 1302 1303 /* sendbuf acct. policy. */ 1304 __u32 sndbuf_policy; 1305 1306 /* rcvbuf acct. policy. */ 1307 __u32 rcvbuf_policy; 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 ecn_enable:1, 1319 auth_enable:1, 1320 intl_enable:1, 1321 prsctp_enable:1, 1322 asconf_enable:1, 1323 reconf_enable:1; 1324 1325 __u8 strreset_enable; 1326 struct rcu_head rcu; 1327 }; 1328 1329 /* Recover the outer endpoint structure. */ 1330 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base) 1331 { 1332 struct sctp_endpoint *ep; 1333 1334 ep = container_of(base, struct sctp_endpoint, base); 1335 return ep; 1336 } 1337 1338 /* These are function signatures for manipulating endpoints. */ 1339 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t); 1340 void sctp_endpoint_free(struct sctp_endpoint *); 1341 void sctp_endpoint_put(struct sctp_endpoint *); 1342 int sctp_endpoint_hold(struct sctp_endpoint *ep); 1343 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *); 1344 struct sctp_association *sctp_endpoint_lookup_assoc( 1345 const struct sctp_endpoint *ep, 1346 const union sctp_addr *paddr, 1347 struct sctp_transport **); 1348 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep, 1349 const union sctp_addr *paddr); 1350 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *ep, 1351 struct net *net, 1352 const union sctp_addr *laddr, 1353 int dif, int sdif); 1354 bool sctp_has_association(struct net *net, const union sctp_addr *laddr, 1355 const union sctp_addr *paddr, int dif, int sdif); 1356 1357 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep, 1358 const struct sctp_association *asoc, 1359 enum sctp_cid cid, struct sctp_init_chunk *peer_init, 1360 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk); 1361 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk, 1362 const union sctp_addr *peer, 1363 struct sctp_init_chunk *init, gfp_t gfp); 1364 __u32 sctp_generate_tag(const struct sctp_endpoint *); 1365 __u32 sctp_generate_tsn(const struct sctp_endpoint *); 1366 1367 struct sctp_inithdr_host { 1368 __u32 init_tag; 1369 __u32 a_rwnd; 1370 __u16 num_outbound_streams; 1371 __u16 num_inbound_streams; 1372 __u32 initial_tsn; 1373 }; 1374 1375 struct sctp_stream_priorities { 1376 /* List of priorities scheduled */ 1377 struct list_head prio_sched; 1378 /* List of streams scheduled */ 1379 struct list_head active; 1380 /* The next stream in line */ 1381 struct sctp_stream_out_ext *next; 1382 __u16 prio; 1383 __u16 users; 1384 }; 1385 1386 struct sctp_stream_out_ext { 1387 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 1388 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 1389 struct list_head outq; /* chunks enqueued by this stream */ 1390 union { 1391 struct { 1392 /* Scheduled streams list */ 1393 struct list_head prio_list; 1394 struct sctp_stream_priorities *prio_head; 1395 }; 1396 /* Fields used by RR scheduler */ 1397 struct { 1398 struct list_head rr_list; 1399 }; 1400 struct { 1401 struct list_head fc_list; 1402 __u32 fc_length; 1403 __u16 fc_weight; 1404 }; 1405 }; 1406 }; 1407 1408 struct sctp_stream_out { 1409 union { 1410 __u32 mid; 1411 __u16 ssn; 1412 }; 1413 __u32 mid_uo; 1414 struct sctp_stream_out_ext *ext; 1415 __u8 state; 1416 }; 1417 1418 struct sctp_stream_in { 1419 union { 1420 __u32 mid; 1421 __u16 ssn; 1422 }; 1423 __u32 mid_uo; 1424 __u32 fsn; 1425 __u32 fsn_uo; 1426 char pd_mode; 1427 char pd_mode_uo; 1428 }; 1429 1430 struct sctp_stream { 1431 GENRADIX(struct sctp_stream_out) out; 1432 GENRADIX(struct sctp_stream_in) in; 1433 1434 __u16 outcnt; 1435 __u16 incnt; 1436 /* Current stream being sent, if any */ 1437 struct sctp_stream_out *out_curr; 1438 union { 1439 /* Fields used by priority scheduler */ 1440 struct { 1441 /* List of priorities scheduled */ 1442 struct list_head prio_list; 1443 }; 1444 /* Fields used by RR scheduler */ 1445 struct { 1446 /* List of streams scheduled */ 1447 struct list_head rr_list; 1448 /* The next stream in line */ 1449 struct sctp_stream_out_ext *rr_next; 1450 }; 1451 struct { 1452 struct list_head fc_list; 1453 }; 1454 }; 1455 struct sctp_stream_interleave *si; 1456 }; 1457 1458 static inline struct sctp_stream_out *sctp_stream_out( 1459 struct sctp_stream *stream, 1460 __u16 sid) 1461 { 1462 return genradix_ptr(&stream->out, sid); 1463 } 1464 1465 static inline struct sctp_stream_in *sctp_stream_in( 1466 struct sctp_stream *stream, 1467 __u16 sid) 1468 { 1469 return genradix_ptr(&stream->in, sid); 1470 } 1471 1472 #define SCTP_SO(s, i) sctp_stream_out((s), (i)) 1473 #define SCTP_SI(s, i) sctp_stream_in((s), (i)) 1474 1475 #define SCTP_STREAM_CLOSED 0x00 1476 #define SCTP_STREAM_OPEN 0x01 1477 1478 static inline __u16 sctp_datachk_len(const struct sctp_stream *stream) 1479 { 1480 return stream->si->data_chunk_len; 1481 } 1482 1483 static inline __u16 sctp_datahdr_len(const struct sctp_stream *stream) 1484 { 1485 return stream->si->data_chunk_len - sizeof(struct sctp_chunkhdr); 1486 } 1487 1488 static inline __u16 sctp_ftsnchk_len(const struct sctp_stream *stream) 1489 { 1490 return stream->si->ftsn_chunk_len; 1491 } 1492 1493 static inline __u16 sctp_ftsnhdr_len(const struct sctp_stream *stream) 1494 { 1495 return stream->si->ftsn_chunk_len - sizeof(struct sctp_chunkhdr); 1496 } 1497 1498 /* SCTP_GET_ASSOC_STATS counters */ 1499 struct sctp_priv_assoc_stats { 1500 /* Maximum observed rto in the association during subsequent 1501 * observations. Value is set to 0 if no RTO measurement took place 1502 * The transport where the max_rto was observed is returned in 1503 * obs_rto_ipaddr 1504 */ 1505 struct sockaddr_storage obs_rto_ipaddr; 1506 __u64 max_obs_rto; 1507 /* Total In and Out SACKs received and sent */ 1508 __u64 isacks; 1509 __u64 osacks; 1510 /* Total In and Out packets received and sent */ 1511 __u64 opackets; 1512 __u64 ipackets; 1513 /* Total retransmitted chunks */ 1514 __u64 rtxchunks; 1515 /* TSN received > next expected */ 1516 __u64 outofseqtsns; 1517 /* Duplicate Chunks received */ 1518 __u64 idupchunks; 1519 /* Gap Ack Blocks received */ 1520 __u64 gapcnt; 1521 /* Unordered data chunks sent and received */ 1522 __u64 ouodchunks; 1523 __u64 iuodchunks; 1524 /* Ordered data chunks sent and received */ 1525 __u64 oodchunks; 1526 __u64 iodchunks; 1527 /* Control chunks sent and received */ 1528 __u64 octrlchunks; 1529 __u64 ictrlchunks; 1530 }; 1531 1532 /* RFC2960 1533 * 1534 * 12. Recommended Transmission Control Block (TCB) Parameters 1535 * 1536 * This section details a recommended set of parameters that should 1537 * be contained within the TCB for an implementation. This section is 1538 * for illustrative purposes and should not be deemed as requirements 1539 * on an implementation or as an exhaustive list of all parameters 1540 * inside an SCTP TCB. Each implementation may need its own additional 1541 * parameters for optimization. 1542 */ 1543 1544 1545 /* Here we have information about each individual association. */ 1546 struct sctp_association { 1547 1548 /* A base structure common to endpoint and association. 1549 * In this context, it represents the associations's view 1550 * of the local endpoint of the association. 1551 */ 1552 struct sctp_ep_common base; 1553 1554 /* Associations on the same socket. */ 1555 struct list_head asocs; 1556 1557 /* association id. */ 1558 sctp_assoc_t assoc_id; 1559 1560 /* This is our parent endpoint. */ 1561 struct sctp_endpoint *ep; 1562 1563 /* These are those association elements needed in the cookie. */ 1564 struct sctp_cookie c; 1565 1566 /* This is all information about our peer. */ 1567 struct { 1568 /* transport_addr_list 1569 * 1570 * Peer : A list of SCTP transport addresses that the 1571 * Transport : peer is bound to. This information is derived 1572 * Address : from the INIT or INIT ACK and is used to 1573 * List : associate an inbound packet with a given 1574 * : association. Normally this information is 1575 * : hashed or keyed for quick lookup and access 1576 * : of the TCB. 1577 * : The list is also initialized with the list 1578 * : of addresses passed with the sctp_connectx() 1579 * : call. 1580 * 1581 * It is a list of SCTP_transport's. 1582 */ 1583 struct list_head transport_addr_list; 1584 1585 /* rwnd 1586 * 1587 * Peer Rwnd : Current calculated value of the peer's rwnd. 1588 */ 1589 __u32 rwnd; 1590 1591 /* transport_count 1592 * 1593 * Peer : A count of the number of peer addresses 1594 * Transport : in the Peer Transport Address List. 1595 * Address : 1596 * Count : 1597 */ 1598 __u16 transport_count; 1599 1600 /* port 1601 * The transport layer port number. 1602 */ 1603 __u16 port; 1604 1605 /* primary_path 1606 * 1607 * Primary : This is the current primary destination 1608 * Path : transport address of the peer endpoint. It 1609 * : may also specify a source transport address 1610 * : on this endpoint. 1611 * 1612 * All of these paths live on transport_addr_list. 1613 * 1614 * At the bakeoffs, we discovered that the intent of 1615 * primaryPath is that it only changes when the ULP 1616 * asks to have it changed. We add the activePath to 1617 * designate the connection we are currently using to 1618 * transmit new data and most control chunks. 1619 */ 1620 struct sctp_transport *primary_path; 1621 1622 /* Cache the primary path address here, when we 1623 * need a an address for msg_name. 1624 */ 1625 union sctp_addr primary_addr; 1626 1627 /* active_path 1628 * The path that we are currently using to 1629 * transmit new data and most control chunks. 1630 */ 1631 struct sctp_transport *active_path; 1632 1633 /* retran_path 1634 * 1635 * RFC2960 6.4 Multi-homed SCTP Endpoints 1636 * ... 1637 * Furthermore, when its peer is multi-homed, an 1638 * endpoint SHOULD try to retransmit a chunk to an 1639 * active destination transport address that is 1640 * different from the last destination address to 1641 * which the DATA chunk was sent. 1642 */ 1643 struct sctp_transport *retran_path; 1644 1645 /* Pointer to last transport I have sent on. */ 1646 struct sctp_transport *last_sent_to; 1647 1648 /* This is the last transport I have received DATA on. */ 1649 struct sctp_transport *last_data_from; 1650 1651 /* 1652 * Mapping An array of bits or bytes indicating which out of 1653 * Array order TSN's have been received (relative to the 1654 * Last Rcvd TSN). If no gaps exist, i.e. no out of 1655 * order packets have been received, this array 1656 * will be set to all zero. This structure may be 1657 * in the form of a circular buffer or bit array. 1658 * 1659 * Last Rcvd : This is the last TSN received in 1660 * TSN : sequence. This value is set initially by 1661 * : taking the peer's Initial TSN, received in 1662 * : the INIT or INIT ACK chunk, and subtracting 1663 * : one from it. 1664 * 1665 * Throughout most of the specification this is called the 1666 * "Cumulative TSN ACK Point". In this case, we 1667 * ignore the advice in 12.2 in favour of the term 1668 * used in the bulk of the text. This value is hidden 1669 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn(). 1670 */ 1671 struct sctp_tsnmap tsn_map; 1672 1673 /* This mask is used to disable sending the ASCONF chunk 1674 * with specified parameter to peer. 1675 */ 1676 __be16 addip_disabled_mask; 1677 1678 /* These are capabilities which our peer advertised. */ 1679 __u16 ecn_capable:1, /* Can peer do ECN? */ 1680 ipv4_address:1, /* Peer understands IPv4 addresses? */ 1681 ipv6_address:1, /* Peer understands IPv6 addresses? */ 1682 asconf_capable:1, /* Does peer support ADDIP? */ 1683 prsctp_capable:1, /* Can peer do PR-SCTP? */ 1684 reconf_capable:1, /* Can peer do RE-CONFIG? */ 1685 intl_capable:1, /* Can peer do INTERLEAVE */ 1686 auth_capable:1, /* Is peer doing SCTP-AUTH? */ 1687 /* sack_needed: 1688 * This flag indicates if the next received 1689 * packet is to be responded to with a 1690 * SACK. This is initialized to 0. When a packet 1691 * is received sack_cnt is incremented. If this value 1692 * reaches 2 or more, a SACK is sent and the 1693 * value is reset to 0. Note: This is used only 1694 * when no DATA chunks are received out of 1695 * order. When DATA chunks are out of order, 1696 * SACK's are not delayed (see Section 6). 1697 */ 1698 sack_needed:1, /* Do we need to sack the peer? */ 1699 sack_generation:1, 1700 zero_window_announced:1; 1701 1702 __u32 sack_cnt; 1703 1704 __u32 adaptation_ind; /* Adaptation Code point. */ 1705 1706 struct sctp_inithdr_host i; 1707 void *cookie; 1708 int cookie_len; 1709 1710 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. 1711 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the 1712 * Initial TSN Value minus 1 1713 */ 1714 __u32 addip_serial; 1715 1716 /* SCTP-AUTH: We need to know pears random number, hmac list 1717 * and authenticated chunk list. All that is part of the 1718 * cookie and these are just pointers to those locations 1719 */ 1720 struct sctp_random_param *peer_random; 1721 struct sctp_chunks_param *peer_chunks; 1722 struct sctp_hmac_algo_param *peer_hmacs; 1723 } peer; 1724 1725 /* State : A state variable indicating what state the 1726 * : association is in, i.e. COOKIE-WAIT, 1727 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING, 1728 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT. 1729 * 1730 * Note: No "CLOSED" state is illustrated since if a 1731 * association is "CLOSED" its TCB SHOULD be removed. 1732 * 1733 * In this implementation we DO have a CLOSED 1734 * state which is used during initiation and shutdown. 1735 * 1736 * State takes values from SCTP_STATE_*. 1737 */ 1738 enum sctp_state state; 1739 1740 /* Overall : The overall association error count. 1741 * Error Count : [Clear this any time I get something.] 1742 */ 1743 int overall_error_count; 1744 1745 /* The cookie life I award for any cookie. */ 1746 ktime_t cookie_life; 1747 1748 /* These are the association's initial, max, and min RTO values. 1749 * These values will be initialized by system defaults, but can 1750 * be modified via the SCTP_RTOINFO socket option. 1751 */ 1752 unsigned long rto_initial; 1753 unsigned long rto_max; 1754 unsigned long rto_min; 1755 1756 /* Maximum number of new data packets that can be sent in a burst. */ 1757 int max_burst; 1758 1759 /* This is the max_retrans value for the association. This value will 1760 * be initialized from system defaults, but can be 1761 * modified by the SCTP_ASSOCINFO socket option. 1762 */ 1763 int max_retrans; 1764 1765 /* This is the partially failed retrans value for the transport 1766 * and will be initialized from the assocs value. This can be 1767 * changed using the SCTP_PEER_ADDR_THLDS socket option 1768 */ 1769 __u16 pf_retrans; 1770 /* Used for primary path switchover. */ 1771 __u16 ps_retrans; 1772 1773 /* Maximum number of times the endpoint will retransmit INIT */ 1774 __u16 max_init_attempts; 1775 1776 /* How many times have we resent an INIT? */ 1777 __u16 init_retries; 1778 1779 /* The largest timeout or RTO value to use in attempting an INIT */ 1780 unsigned long max_init_timeo; 1781 1782 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 1783 * the destination address every heartbeat interval. This value 1784 * will be inherited by all new transports. 1785 */ 1786 unsigned long hbinterval; 1787 unsigned long probe_interval; 1788 1789 __be16 encap_port; 1790 1791 /* This is the max_retrans value for new transports in the 1792 * association. 1793 */ 1794 __u16 pathmaxrxt; 1795 1796 __u32 flowlabel; 1797 __u8 dscp; 1798 1799 /* Flag that path mtu update is pending */ 1800 __u8 pmtu_pending; 1801 1802 /* Association : The smallest PMTU discovered for all of the 1803 * PMTU : peer's transport addresses. 1804 */ 1805 __u32 pathmtu; 1806 1807 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 1808 __u32 param_flags; 1809 1810 __u32 sackfreq; 1811 /* SACK delay timeout */ 1812 unsigned long sackdelay; 1813 1814 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES]; 1815 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES]; 1816 1817 /* Transport to which SHUTDOWN chunk was last sent. */ 1818 struct sctp_transport *shutdown_last_sent_to; 1819 1820 /* Transport to which INIT chunk was last sent. */ 1821 struct sctp_transport *init_last_sent_to; 1822 1823 /* How many times have we resent a SHUTDOWN */ 1824 int shutdown_retries; 1825 1826 /* Next TSN : The next TSN number to be assigned to a new 1827 * : DATA chunk. This is sent in the INIT or INIT 1828 * : ACK chunk to the peer and incremented each 1829 * : time a DATA chunk is assigned a TSN 1830 * : (normally just prior to transmit or during 1831 * : fragmentation). 1832 */ 1833 __u32 next_tsn; 1834 1835 /* 1836 * Last Rcvd : This is the last TSN received in sequence. This value 1837 * TSN : is set initially by taking the peer's Initial TSN, 1838 * : received in the INIT or INIT ACK chunk, and 1839 * : subtracting one from it. 1840 * 1841 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point. 1842 */ 1843 1844 __u32 ctsn_ack_point; 1845 1846 /* PR-SCTP Advanced.Peer.Ack.Point */ 1847 __u32 adv_peer_ack_point; 1848 1849 /* Highest TSN that is acknowledged by incoming SACKs. */ 1850 __u32 highest_sacked; 1851 1852 /* TSN marking the fast recovery exit point */ 1853 __u32 fast_recovery_exit; 1854 1855 /* Flag to track the current fast recovery state */ 1856 __u8 fast_recovery; 1857 1858 /* The number of unacknowledged data chunks. Reported through 1859 * the SCTP_STATUS sockopt. 1860 */ 1861 __u16 unack_data; 1862 1863 /* The total number of data chunks that we've had to retransmit 1864 * as the result of a T3 timer expiration 1865 */ 1866 __u32 rtx_data_chunks; 1867 1868 /* This is the association's receive buffer space. This value is used 1869 * to set a_rwnd field in an INIT or a SACK chunk. 1870 */ 1871 __u32 rwnd; 1872 1873 /* This is the last advertised value of rwnd over a SACK chunk. */ 1874 __u32 a_rwnd; 1875 1876 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed 1877 * to slop over a maximum of the association's frag_point. 1878 */ 1879 __u32 rwnd_over; 1880 1881 /* Keeps treack of rwnd pressure. This happens when we have 1882 * a window, but not receive buffer (i.e small packets). This one 1883 * is releases slowly (1 PMTU at a time ). 1884 */ 1885 __u32 rwnd_press; 1886 1887 /* This is the sndbuf size in use for the association. 1888 * This corresponds to the sndbuf size for the association, 1889 * as specified in the sk->sndbuf. 1890 */ 1891 int sndbuf_used; 1892 1893 /* This is the amount of memory that this association has allocated 1894 * in the receive path at any given time. 1895 */ 1896 atomic_t rmem_alloc; 1897 1898 /* This is the wait queue head for send requests waiting on 1899 * the association sndbuf space. 1900 */ 1901 wait_queue_head_t wait; 1902 1903 /* The message size at which SCTP fragmentation will occur. */ 1904 __u32 frag_point; 1905 __u32 user_frag; 1906 1907 /* Counter used to count INIT errors. */ 1908 int init_err_counter; 1909 1910 /* Count the number of INIT cycles (for doubling timeout). */ 1911 int init_cycle; 1912 1913 /* Default send parameters. */ 1914 __u16 default_stream; 1915 __u16 default_flags; 1916 __u32 default_ppid; 1917 __u32 default_context; 1918 __u32 default_timetolive; 1919 1920 /* Default receive parameters */ 1921 __u32 default_rcv_context; 1922 1923 /* Stream arrays */ 1924 struct sctp_stream stream; 1925 1926 /* All outbound chunks go through this structure. */ 1927 struct sctp_outq outqueue; 1928 1929 /* A smart pipe that will handle reordering and fragmentation, 1930 * as well as handle passing events up to the ULP. 1931 */ 1932 struct sctp_ulpq ulpq; 1933 1934 /* Last TSN that caused an ECNE Chunk to be sent. */ 1935 __u32 last_ecne_tsn; 1936 1937 /* Last TSN that caused a CWR Chunk to be sent. */ 1938 __u32 last_cwr_tsn; 1939 1940 /* How many duplicated TSNs have we seen? */ 1941 int numduptsns; 1942 1943 /* These are to support 1944 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses 1945 * and Enforcement of Flow and Message Limits" 1946 * <draft-ietf-tsvwg-addip-sctp-02.txt> 1947 * or "ADDIP" for short. 1948 */ 1949 1950 1951 1952 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1953 * 1954 * R1) One and only one ASCONF Chunk MAY be in transit and 1955 * unacknowledged at any one time. If a sender, after sending 1956 * an ASCONF chunk, decides it needs to transfer another 1957 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1958 * returns from the previous ASCONF Chunk before sending a 1959 * subsequent ASCONF. Note this restriction binds each side, 1960 * so at any time two ASCONF may be in-transit on any given 1961 * association (one sent from each endpoint). 1962 * 1963 * [This is our one-and-only-one ASCONF in flight. If we do 1964 * not have an ASCONF in flight, this is NULL.] 1965 */ 1966 struct sctp_chunk *addip_last_asconf; 1967 1968 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk. 1969 * 1970 * This is needed to implement items E1 - E4 of the updated 1971 * spec. Here is the justification: 1972 * 1973 * Since the peer may bundle multiple ASCONF chunks toward us, 1974 * we now need the ability to cache multiple ACKs. The section 1975 * describes in detail how they are cached and cleaned up. 1976 */ 1977 struct list_head asconf_ack_list; 1978 1979 /* These ASCONF chunks are waiting to be sent. 1980 * 1981 * These chunks can't be pushed to outqueue until receiving 1982 * ASCONF_ACK for the previous ASCONF indicated by 1983 * addip_last_asconf, so as to guarantee that only one ASCONF 1984 * is in flight at any time. 1985 * 1986 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1987 * 1988 * In defining the ASCONF Chunk transfer procedures, it is 1989 * essential that these transfers MUST NOT cause congestion 1990 * within the network. To achieve this, we place these 1991 * restrictions on the transfer of ASCONF Chunks: 1992 * 1993 * R1) One and only one ASCONF Chunk MAY be in transit and 1994 * unacknowledged at any one time. If a sender, after sending 1995 * an ASCONF chunk, decides it needs to transfer another 1996 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1997 * returns from the previous ASCONF Chunk before sending a 1998 * subsequent ASCONF. Note this restriction binds each side, 1999 * so at any time two ASCONF may be in-transit on any given 2000 * association (one sent from each endpoint). 2001 * 2002 * 2003 * [I really think this is EXACTLY the sort of intelligence 2004 * which already resides in sctp_outq. Please move this 2005 * queue and its supporting logic down there. --piggy] 2006 */ 2007 struct list_head addip_chunk_list; 2008 2009 /* ADDIP Section 4.1 ASCONF Chunk Procedures 2010 * 2011 * A2) A serial number should be assigned to the Chunk. The 2012 * serial number SHOULD be a monotonically increasing 2013 * number. The serial number SHOULD be initialized at 2014 * the start of the association to the same value as the 2015 * Initial TSN and every time a new ASCONF chunk is created 2016 * it is incremented by one after assigning the serial number 2017 * to the newly created chunk. 2018 * 2019 * ADDIP 2020 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF) 2021 * 2022 * Serial Number : 32 bits (unsigned integer) 2023 * 2024 * This value represents a Serial Number for the ASCONF 2025 * Chunk. The valid range of Serial Number is from 0 to 2026 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0 2027 * after reaching 4294967295. 2028 */ 2029 __u32 addip_serial; 2030 int src_out_of_asoc_ok; 2031 union sctp_addr *asconf_addr_del_pending; 2032 struct sctp_transport *new_transport; 2033 2034 /* SCTP AUTH: list of the endpoint shared keys. These 2035 * keys are provided out of band by the user application 2036 * and can't change during the lifetime of the association 2037 */ 2038 struct list_head endpoint_shared_keys; 2039 2040 /* SCTP AUTH: 2041 * The current generated association shared key (secret) 2042 */ 2043 struct sctp_auth_bytes *asoc_shared_key; 2044 struct sctp_shared_key *shkey; 2045 2046 /* SCTP AUTH: hmac id of the first peer requested algorithm 2047 * that we support. 2048 */ 2049 __u16 default_hmac_id; 2050 2051 __u16 active_key_id; 2052 2053 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */ 2054 temp:1, /* Is it a temporary association? */ 2055 pf_expose:2, /* Expose pf state? */ 2056 force_delay:1; 2057 2058 __u8 strreset_enable; 2059 __u8 strreset_outstanding; /* request param count on the fly */ 2060 2061 __u32 strreset_outseq; /* Update after receiving response */ 2062 __u32 strreset_inseq; /* Update after receiving request */ 2063 __u32 strreset_result[2]; /* save the results of last 2 responses */ 2064 2065 struct sctp_chunk *strreset_chunk; /* save request chunk */ 2066 2067 struct sctp_priv_assoc_stats stats; 2068 2069 int sent_cnt_removable; 2070 2071 __u16 subscribe; 2072 2073 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 2074 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 2075 2076 /* Security identifiers from incoming (INIT). These are set by 2077 * security_sctp_assoc_request(). These will only be used by 2078 * SCTP TCP type sockets and peeled off connections as they 2079 * cause a new socket to be generated. security_sctp_sk_clone() 2080 * will then plug these into the new socket. 2081 */ 2082 2083 u32 secid; 2084 u32 peer_secid; 2085 2086 struct rcu_head rcu; 2087 }; 2088 2089 2090 /* An eyecatcher for determining if we are really looking at an 2091 * association data structure. 2092 */ 2093 enum { 2094 SCTP_ASSOC_EYECATCHER = 0xa550c123, 2095 }; 2096 2097 /* Recover the outer association structure. */ 2098 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base) 2099 { 2100 struct sctp_association *asoc; 2101 2102 asoc = container_of(base, struct sctp_association, base); 2103 return asoc; 2104 } 2105 2106 /* These are function signatures for manipulating associations. */ 2107 2108 2109 struct sctp_association * 2110 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk, 2111 enum sctp_scope scope, gfp_t gfp); 2112 void sctp_association_free(struct sctp_association *); 2113 void sctp_association_put(struct sctp_association *); 2114 void sctp_association_hold(struct sctp_association *); 2115 2116 struct sctp_transport *sctp_assoc_choose_alter_transport( 2117 struct sctp_association *, struct sctp_transport *); 2118 void sctp_assoc_update_retran_path(struct sctp_association *); 2119 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *, 2120 const union sctp_addr *); 2121 int sctp_assoc_lookup_laddr(struct sctp_association *asoc, 2122 const union sctp_addr *laddr); 2123 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *, 2124 const union sctp_addr *address, 2125 const gfp_t gfp, 2126 const int peer_state); 2127 void sctp_assoc_rm_peer(struct sctp_association *asoc, 2128 struct sctp_transport *peer); 2129 void sctp_assoc_control_transport(struct sctp_association *asoc, 2130 struct sctp_transport *transport, 2131 enum sctp_transport_cmd command, 2132 sctp_sn_error_t error); 2133 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32); 2134 void sctp_assoc_migrate(struct sctp_association *, struct sock *); 2135 int sctp_assoc_update(struct sctp_association *old, 2136 struct sctp_association *new); 2137 2138 __u32 sctp_association_get_next_tsn(struct sctp_association *); 2139 2140 void sctp_assoc_update_frag_point(struct sctp_association *asoc); 2141 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu); 2142 void sctp_assoc_sync_pmtu(struct sctp_association *asoc); 2143 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int); 2144 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int); 2145 void sctp_assoc_set_primary(struct sctp_association *, 2146 struct sctp_transport *); 2147 void sctp_assoc_del_nonprimary_peers(struct sctp_association *, 2148 struct sctp_transport *); 2149 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, 2150 enum sctp_scope scope, gfp_t gfp); 2151 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *, 2152 struct sctp_cookie*, 2153 gfp_t gfp); 2154 int sctp_assoc_set_id(struct sctp_association *, gfp_t); 2155 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc); 2156 struct sctp_chunk *sctp_assoc_lookup_asconf_ack( 2157 const struct sctp_association *asoc, 2158 __be32 serial); 2159 void sctp_asconf_queue_teardown(struct sctp_association *asoc); 2160 2161 int sctp_cmp_addr_exact(const union sctp_addr *ss1, 2162 const union sctp_addr *ss2); 2163 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc); 2164 2165 /* A convenience structure to parse out SCTP specific CMSGs. */ 2166 struct sctp_cmsgs { 2167 struct sctp_initmsg *init; 2168 struct sctp_sndrcvinfo *srinfo; 2169 struct sctp_sndinfo *sinfo; 2170 struct sctp_prinfo *prinfo; 2171 struct sctp_authinfo *authinfo; 2172 struct msghdr *addrs_msg; 2173 }; 2174 2175 /* Structure for tracking memory objects */ 2176 struct sctp_dbg_objcnt_entry { 2177 char *label; 2178 atomic_t *counter; 2179 }; 2180 2181 #endif /* __sctp_structs_h__ */ 2182