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[sizeof(struct sctp_paramhdr) + 316 SCTP_AUTH_NUM_HMACS * sizeof(__u16)]; 317 __u8 auth_chunks[sizeof(struct sctp_paramhdr) + SCTP_AUTH_MAX_CHUNKS]; 318 319 /* This is a shim for my peer's INIT packet, followed by 320 * a copy of the raw address list of the association. 321 * The length of the raw address list is saved in the 322 * raw_addr_list_len field, which will be used at the time when 323 * the association TCB is re-constructed from the cookie. 324 */ 325 __u32 raw_addr_list_len; 326 /* struct sctp_init_chunk peer_init[]; */ 327 }; 328 329 330 /* The format of our cookie that we send to our peer. */ 331 struct sctp_signed_cookie { 332 __u8 mac[SCTP_COOKIE_MAC_SIZE]; 333 __u32 __pad; /* force sctp_cookie alignment to 64 bits */ 334 struct sctp_cookie c; 335 } __packed; 336 337 /* This is another convenience type to allocate memory for address 338 * params for the maximum size and pass such structures around 339 * internally. 340 */ 341 union sctp_addr_param { 342 struct sctp_paramhdr p; 343 struct sctp_ipv4addr_param v4; 344 struct sctp_ipv6addr_param v6; 345 }; 346 347 /* A convenience type to allow walking through the various 348 * parameters and avoid casting all over the place. 349 */ 350 union sctp_params { 351 void *v; 352 struct sctp_paramhdr *p; 353 struct sctp_cookie_preserve_param *life; 354 struct sctp_hostname_param *dns; 355 struct sctp_cookie_param *cookie; 356 struct sctp_supported_addrs_param *sat; 357 struct sctp_ipv4addr_param *v4; 358 struct sctp_ipv6addr_param *v6; 359 union sctp_addr_param *addr; 360 struct sctp_adaptation_ind_param *aind; 361 struct sctp_supported_ext_param *ext; 362 struct sctp_random_param *random; 363 struct sctp_chunks_param *chunks; 364 struct sctp_hmac_algo_param *hmac_algo; 365 struct sctp_addip_param *addip; 366 }; 367 368 /* RFC 2960. Section 3.3.5 Heartbeat. 369 * Heartbeat Information: variable length 370 * The Sender-specific Heartbeat Info field should normally include 371 * information about the sender's current time when this HEARTBEAT 372 * chunk is sent and the destination transport address to which this 373 * HEARTBEAT is sent (see Section 8.3). 374 */ 375 struct sctp_sender_hb_info { 376 struct sctp_paramhdr param_hdr; 377 union sctp_addr daddr; 378 unsigned long sent_at; 379 __u64 hb_nonce; 380 __u32 probe_size; 381 }; 382 383 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt, 384 gfp_t gfp); 385 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid); 386 void sctp_stream_free(struct sctp_stream *stream); 387 void sctp_stream_clear(struct sctp_stream *stream); 388 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new); 389 390 /* What is the current SSN number for this stream? */ 391 #define sctp_ssn_peek(stream, type, sid) \ 392 (sctp_stream_##type((stream), (sid))->ssn) 393 394 /* Return the next SSN number for this stream. */ 395 #define sctp_ssn_next(stream, type, sid) \ 396 (sctp_stream_##type((stream), (sid))->ssn++) 397 398 /* Skip over this ssn and all below. */ 399 #define sctp_ssn_skip(stream, type, sid, ssn) \ 400 (sctp_stream_##type((stream), (sid))->ssn = ssn + 1) 401 402 /* What is the current MID number for this stream? */ 403 #define sctp_mid_peek(stream, type, sid) \ 404 (sctp_stream_##type((stream), (sid))->mid) 405 406 /* Return the next MID number for this stream. */ 407 #define sctp_mid_next(stream, type, sid) \ 408 (sctp_stream_##type((stream), (sid))->mid++) 409 410 /* Skip over this mid and all below. */ 411 #define sctp_mid_skip(stream, type, sid, mid) \ 412 (sctp_stream_##type((stream), (sid))->mid = mid + 1) 413 414 /* What is the current MID_uo number for this stream? */ 415 #define sctp_mid_uo_peek(stream, type, sid) \ 416 (sctp_stream_##type((stream), (sid))->mid_uo) 417 418 /* Return the next MID_uo number for this stream. */ 419 #define sctp_mid_uo_next(stream, type, sid) \ 420 (sctp_stream_##type((stream), (sid))->mid_uo++) 421 422 /* 423 * Pointers to address related SCTP functions. 424 * (i.e. things that depend on the address family.) 425 */ 426 struct sctp_af { 427 int (*sctp_xmit) (struct sk_buff *skb, 428 struct sctp_transport *); 429 int (*setsockopt) (struct sock *sk, 430 int level, 431 int optname, 432 sockptr_t optval, 433 unsigned int optlen); 434 int (*getsockopt) (struct sock *sk, 435 int level, 436 int optname, 437 char __user *optval, 438 int __user *optlen); 439 void (*get_dst) (struct sctp_transport *t, 440 union sctp_addr *saddr, 441 struct flowi *fl, 442 struct sock *sk); 443 void (*get_saddr) (struct sctp_sock *sk, 444 struct sctp_transport *t, 445 struct flowi *fl); 446 void (*copy_addrlist) (struct list_head *, 447 struct net_device *); 448 int (*cmp_addr) (const union sctp_addr *addr1, 449 const union sctp_addr *addr2); 450 void (*addr_copy) (union sctp_addr *dst, 451 union sctp_addr *src); 452 void (*from_skb) (union sctp_addr *, 453 struct sk_buff *skb, 454 int saddr); 455 void (*from_sk) (union sctp_addr *, 456 struct sock *sk); 457 bool (*from_addr_param) (union sctp_addr *, 458 union sctp_addr_param *, 459 __be16 port, int iif); 460 int (*to_addr_param) (const union sctp_addr *, 461 union sctp_addr_param *); 462 int (*addr_valid) (union sctp_addr *, 463 struct sctp_sock *, 464 const struct sk_buff *); 465 enum sctp_scope (*scope)(union sctp_addr *); 466 void (*inaddr_any) (union sctp_addr *, __be16); 467 int (*is_any) (const union sctp_addr *); 468 int (*available) (union sctp_addr *, 469 struct sctp_sock *); 470 int (*skb_iif) (const struct sk_buff *sk); 471 int (*skb_sdif)(const struct sk_buff *sk); 472 int (*is_ce) (const struct sk_buff *sk); 473 void (*seq_dump_addr)(struct seq_file *seq, 474 union sctp_addr *addr); 475 void (*ecn_capable)(struct sock *sk); 476 __u16 net_header_len; 477 int sockaddr_len; 478 int (*ip_options_len)(struct sock *sk); 479 sa_family_t sa_family; 480 struct list_head list; 481 }; 482 483 struct sctp_af *sctp_get_af_specific(sa_family_t); 484 int sctp_register_af(struct sctp_af *); 485 486 /* Protocol family functions. */ 487 struct sctp_pf { 488 void (*event_msgname)(struct sctp_ulpevent *, char *, int *); 489 void (*skb_msgname) (struct sk_buff *, char *, int *); 490 int (*af_supported) (sa_family_t, struct sctp_sock *); 491 int (*cmp_addr) (const union sctp_addr *, 492 const union sctp_addr *, 493 struct sctp_sock *); 494 int (*bind_verify) (struct sctp_sock *, union sctp_addr *); 495 int (*send_verify) (struct sctp_sock *, union sctp_addr *); 496 int (*supported_addrs)(const struct sctp_sock *, __be16 *); 497 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr); 498 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk); 499 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk); 500 void (*copy_ip_options)(struct sock *sk, struct sock *newsk); 501 struct sctp_af *af; 502 }; 503 504 505 /* Structure to track chunk fragments that have been acked, but peer 506 * fragments of the same message have not. 507 */ 508 struct sctp_datamsg { 509 /* Chunks waiting to be submitted to lower layer. */ 510 struct list_head chunks; 511 /* Reference counting. */ 512 refcount_t refcnt; 513 /* When is this message no longer interesting to the peer? */ 514 unsigned long expires_at; 515 /* Did the message fail to send? */ 516 int send_error; 517 u8 send_failed:1, 518 can_delay:1, /* should this message be Nagle delayed */ 519 abandoned:1; /* should this message be abandoned */ 520 }; 521 522 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *, 523 struct sctp_sndrcvinfo *, 524 struct iov_iter *); 525 void sctp_datamsg_free(struct sctp_datamsg *); 526 void sctp_datamsg_put(struct sctp_datamsg *); 527 void sctp_chunk_fail(struct sctp_chunk *, int error); 528 int sctp_chunk_abandoned(struct sctp_chunk *); 529 530 /* RFC2960 1.4 Key Terms 531 * 532 * o Chunk: A unit of information within an SCTP packet, consisting of 533 * a chunk header and chunk-specific content. 534 * 535 * As a matter of convenience, we remember the SCTP common header for 536 * each chunk as well as a few other header pointers... 537 */ 538 struct sctp_chunk { 539 struct list_head list; 540 541 refcount_t refcnt; 542 543 /* How many times this chunk have been sent, for prsctp RTX policy */ 544 int sent_count; 545 546 union { 547 /* This is our link to the per-transport transmitted list. */ 548 struct list_head transmitted_list; 549 /* List in specific stream outq */ 550 struct list_head stream_list; 551 }; 552 553 /* This field is used by chunks that hold fragmented data. 554 * For the first fragment this is the list that holds the rest of 555 * fragments. For the remaining fragments, this is the link to the 556 * frag_list maintained in the first fragment. 557 */ 558 struct list_head frag_list; 559 560 /* This points to the sk_buff containing the actual data. */ 561 struct sk_buff *skb; 562 563 union { 564 /* In case of GSO packets, this will store the head one */ 565 struct sk_buff *head_skb; 566 /* In case of auth enabled, this will point to the shkey */ 567 struct sctp_shared_key *shkey; 568 }; 569 570 /* These are the SCTP headers by reverse order in a packet. 571 * Note that some of these may happen more than once. In that 572 * case, we point at the "current" one, whatever that means 573 * for that level of header. 574 */ 575 576 /* We point this at the FIRST TLV parameter to chunk_hdr. */ 577 union sctp_params param_hdr; 578 union { 579 __u8 *v; 580 struct sctp_datahdr *data_hdr; 581 struct sctp_inithdr *init_hdr; 582 struct sctp_sackhdr *sack_hdr; 583 struct sctp_heartbeathdr *hb_hdr; 584 struct sctp_sender_hb_info *hbs_hdr; 585 struct sctp_shutdownhdr *shutdown_hdr; 586 struct sctp_signed_cookie *cookie_hdr; 587 struct sctp_ecnehdr *ecne_hdr; 588 struct sctp_cwrhdr *ecn_cwr_hdr; 589 struct sctp_errhdr *err_hdr; 590 struct sctp_addiphdr *addip_hdr; 591 struct sctp_fwdtsn_hdr *fwdtsn_hdr; 592 struct sctp_authhdr *auth_hdr; 593 struct sctp_idatahdr *idata_hdr; 594 struct sctp_ifwdtsn_hdr *ifwdtsn_hdr; 595 } subh; 596 597 __u8 *chunk_end; 598 599 struct sctp_chunkhdr *chunk_hdr; 600 struct sctphdr *sctp_hdr; 601 602 /* This needs to be recoverable for SCTP_SEND_FAILED events. */ 603 struct sctp_sndrcvinfo sinfo; 604 605 /* Which association does this belong to? */ 606 struct sctp_association *asoc; 607 608 /* What endpoint received this chunk? */ 609 struct sctp_ep_common *rcvr; 610 611 /* We fill this in if we are calculating RTT. */ 612 unsigned long sent_at; 613 614 /* What is the origin IP address for this chunk? */ 615 union sctp_addr source; 616 /* Destination address for this chunk. */ 617 union sctp_addr dest; 618 619 /* For outbound message, track all fragments for SEND_FAILED. */ 620 struct sctp_datamsg *msg; 621 622 /* For an inbound chunk, this tells us where it came from. 623 * For an outbound chunk, it tells us where we'd like it to 624 * go. It is NULL if we have no preference. 625 */ 626 struct sctp_transport *transport; 627 628 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO 629 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH 630 * spec violates the principle premis that all chunks are processed 631 * in order. 632 */ 633 struct sk_buff *auth_chunk; 634 635 #define SCTP_CAN_FRTX 0x0 636 #define SCTP_NEED_FRTX 0x1 637 #define SCTP_DONT_FRTX 0x2 638 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */ 639 has_tsn:1, /* Does this chunk have a TSN yet? */ 640 has_ssn:1, /* Does this chunk have a SSN yet? */ 641 #define has_mid has_ssn 642 singleton:1, /* Only chunk in the packet? */ 643 end_of_packet:1, /* Last chunk in the packet? */ 644 ecn_ce_done:1, /* Have we processed the ECN CE bit? */ 645 pdiscard:1, /* Discard the whole packet now? */ 646 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */ 647 data_accepted:1, /* At least 1 chunk accepted */ 648 auth:1, /* IN: was auth'ed | OUT: needs auth */ 649 has_asconf:1, /* IN: have seen an asconf before */ 650 pmtu_probe:1, /* Used by PLPMTUD, can be set in s HB chunk */ 651 tsn_missing_report:2, /* Data chunk missing counter. */ 652 fast_retransmit:2; /* Is this chunk fast retransmitted? */ 653 }; 654 655 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1) 656 void sctp_chunk_hold(struct sctp_chunk *); 657 void sctp_chunk_put(struct sctp_chunk *); 658 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len, 659 struct iov_iter *from); 660 void sctp_chunk_free(struct sctp_chunk *); 661 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data); 662 struct sctp_chunk *sctp_chunkify(struct sk_buff *, 663 const struct sctp_association *, 664 struct sock *, gfp_t gfp); 665 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *, 666 union sctp_addr *); 667 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk); 668 669 static inline __u16 sctp_chunk_stream_no(struct sctp_chunk *ch) 670 { 671 return ntohs(ch->subh.data_hdr->stream); 672 } 673 674 enum { 675 SCTP_ADDR_NEW, /* new address added to assoc/ep */ 676 SCTP_ADDR_SRC, /* address can be used as source */ 677 SCTP_ADDR_DEL, /* address about to be deleted */ 678 }; 679 680 /* This is a structure for holding either an IPv6 or an IPv4 address. */ 681 struct sctp_sockaddr_entry { 682 struct list_head list; 683 struct rcu_head rcu; 684 union sctp_addr a; 685 __u8 state; 686 __u8 valid; 687 }; 688 689 #define SCTP_ADDRESS_TICK_DELAY 500 690 691 /* This structure holds lists of chunks as we are assembling for 692 * transmission. 693 */ 694 struct sctp_packet { 695 /* These are the SCTP header values (host order) for the packet. */ 696 __u16 source_port; 697 __u16 destination_port; 698 __u32 vtag; 699 700 /* This contains the payload chunks. */ 701 struct list_head chunk_list; 702 703 /* This is the overhead of the sctp and ip headers. */ 704 size_t overhead; 705 /* This is the total size of all chunks INCLUDING padding. */ 706 size_t size; 707 /* This is the maximum size this packet may have */ 708 size_t max_size; 709 710 /* The packet is destined for this transport address. 711 * The function we finally use to pass down to the next lower 712 * layer lives in the transport structure. 713 */ 714 struct sctp_transport *transport; 715 716 /* pointer to the auth chunk for this packet */ 717 struct sctp_chunk *auth; 718 719 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */ 720 has_sack:1, /* This packet contains a SACK chunk. */ 721 has_auth:1, /* This packet contains an AUTH chunk */ 722 has_data:1, /* This packet contains at least 1 DATA chunk */ 723 ipfragok:1; /* So let ip fragment this packet */ 724 }; 725 726 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *, 727 __u16 sport, __u16 dport); 728 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int); 729 enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet, 730 struct sctp_chunk *chunk, 731 int one_packet, gfp_t gfp); 732 enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet, 733 struct sctp_chunk *chunk); 734 int sctp_packet_transmit(struct sctp_packet *, gfp_t); 735 void sctp_packet_free(struct sctp_packet *); 736 737 static inline int sctp_packet_empty(struct sctp_packet *packet) 738 { 739 return packet->size == packet->overhead; 740 } 741 742 /* This represents a remote transport address. 743 * For local transport addresses, we just use union sctp_addr. 744 * 745 * RFC2960 Section 1.4 Key Terms 746 * 747 * o Transport address: A Transport Address is traditionally defined 748 * by Network Layer address, Transport Layer protocol and Transport 749 * Layer port number. In the case of SCTP running over IP, a 750 * transport address is defined by the combination of an IP address 751 * and an SCTP port number (where SCTP is the Transport protocol). 752 * 753 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control 754 * 755 * o The sender keeps a separate congestion control parameter set for 756 * each of the destination addresses it can send to (not each 757 * source-destination pair but for each destination). The parameters 758 * should decay if the address is not used for a long enough time 759 * period. 760 * 761 */ 762 struct sctp_transport { 763 /* A list of transports. */ 764 struct list_head transports; 765 struct rhlist_head node; 766 767 /* Reference counting. */ 768 refcount_t refcnt; 769 __u32 dead:1, 770 /* RTO-Pending : A flag used to track if one of the DATA 771 * chunks sent to this address is currently being 772 * used to compute a RTT. If this flag is 0, 773 * the next DATA chunk sent to this destination 774 * should be used to compute a RTT and this flag 775 * should be set. Every time the RTT 776 * calculation completes (i.e. the DATA chunk 777 * is SACK'd) clear this flag. 778 */ 779 rto_pending:1, 780 781 /* 782 * hb_sent : a flag that signals that we have a pending 783 * heartbeat. 784 */ 785 hb_sent:1, 786 787 /* Is the Path MTU update pending on this transport */ 788 pmtu_pending:1, 789 790 dst_pending_confirm:1, /* need to confirm neighbour */ 791 792 /* Has this transport moved the ctsn since we last sacked */ 793 sack_generation:1; 794 u32 dst_cookie; 795 796 struct flowi fl; 797 798 /* This is the peer's IP address and port. */ 799 union sctp_addr ipaddr; 800 801 /* These are the functions we call to handle LLP stuff. */ 802 struct sctp_af *af_specific; 803 804 /* Which association do we belong to? */ 805 struct sctp_association *asoc; 806 807 /* RFC2960 808 * 809 * 12.3 Per Transport Address Data 810 * 811 * For each destination transport address in the peer's 812 * address list derived from the INIT or INIT ACK chunk, a 813 * number of data elements needs to be maintained including: 814 */ 815 /* RTO : The current retransmission timeout value. */ 816 unsigned long rto; 817 818 __u32 rtt; /* This is the most recent RTT. */ 819 820 /* RTTVAR : The current RTT variation. */ 821 __u32 rttvar; 822 823 /* SRTT : The current smoothed round trip time. */ 824 __u32 srtt; 825 826 /* 827 * These are the congestion stats. 828 */ 829 /* cwnd : The current congestion window. */ 830 __u32 cwnd; /* This is the actual cwnd. */ 831 832 /* ssthresh : The current slow start threshold value. */ 833 __u32 ssthresh; 834 835 /* partial : The tracking method for increase of cwnd when in 836 * bytes acked : congestion avoidance mode (see Section 6.2.2) 837 */ 838 __u32 partial_bytes_acked; 839 840 /* Data that has been sent, but not acknowledged. */ 841 __u32 flight_size; 842 843 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */ 844 845 /* Destination */ 846 struct dst_entry *dst; 847 /* Source address. */ 848 union sctp_addr saddr; 849 850 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 851 * the destination address every heartbeat interval. 852 */ 853 unsigned long hbinterval; 854 unsigned long probe_interval; 855 856 /* SACK delay timeout */ 857 unsigned long sackdelay; 858 __u32 sackfreq; 859 860 atomic_t mtu_info; 861 862 /* When was the last time that we heard from this transport? We use 863 * this to pick new active and retran paths. 864 */ 865 ktime_t last_time_heard; 866 867 /* When was the last time that we sent a chunk using this 868 * transport? We use this to check for idle transports 869 */ 870 unsigned long last_time_sent; 871 872 /* Last time(in jiffies) when cwnd is reduced due to the congestion 873 * indication based on ECNE chunk. 874 */ 875 unsigned long last_time_ecne_reduced; 876 877 __be16 encap_port; 878 879 /* This is the max_retrans value for the transport and will 880 * be initialized from the assocs value. This can be changed 881 * using the SCTP_SET_PEER_ADDR_PARAMS socket option. 882 */ 883 __u16 pathmaxrxt; 884 885 __u32 flowlabel; 886 __u8 dscp; 887 888 /* This is the partially failed retrans value for the transport 889 * and will be initialized from the assocs value. This can be changed 890 * using the SCTP_PEER_ADDR_THLDS socket option 891 */ 892 __u16 pf_retrans; 893 /* Used for primary path switchover. */ 894 __u16 ps_retrans; 895 /* PMTU : The current known path MTU. */ 896 __u32 pathmtu; 897 898 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 899 __u32 param_flags; 900 901 /* The number of times INIT has been sent on this transport. */ 902 int init_sent_count; 903 904 /* state : The current state of this destination, 905 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN. 906 */ 907 int state; 908 909 /* These are the error stats for this destination. */ 910 911 /* Error count : The current error count for this destination. */ 912 unsigned short error_count; 913 914 /* Per : A timer used by each destination. 915 * Destination : 916 * Timer : 917 * 918 * [Everywhere else in the text this is called T3-rtx. -ed] 919 */ 920 struct timer_list T3_rtx_timer; 921 922 /* Heartbeat timer is per destination. */ 923 struct timer_list hb_timer; 924 925 /* Timer to handle ICMP proto unreachable envets */ 926 struct timer_list proto_unreach_timer; 927 928 /* Timer to handler reconf chunk rtx */ 929 struct timer_list reconf_timer; 930 931 /* Timer to send a probe HB packet for PLPMTUD */ 932 struct timer_list probe_timer; 933 934 /* Since we're using per-destination retransmission timers 935 * (see above), we're also using per-destination "transmitted" 936 * queues. This probably ought to be a private struct 937 * accessible only within the outqueue, but it's not, yet. 938 */ 939 struct list_head transmitted; 940 941 /* We build bundle-able packets for this transport here. */ 942 struct sctp_packet packet; 943 944 /* This is the list of transports that have chunks to send. */ 945 struct list_head send_ready; 946 947 /* State information saved for SFR_CACC algorithm. The key 948 * idea in SFR_CACC is to maintain state at the sender on a 949 * per-destination basis when a changeover happens. 950 * char changeover_active; 951 * char cycling_changeover; 952 * __u32 next_tsn_at_change; 953 * char cacc_saw_newack; 954 */ 955 struct { 956 /* An unsigned integer, which stores the next TSN to be 957 * used by the sender, at the moment of changeover. 958 */ 959 __u32 next_tsn_at_change; 960 961 /* A flag which indicates the occurrence of a changeover */ 962 char changeover_active; 963 964 /* A flag which indicates whether the change of primary is 965 * the first switch to this destination address during an 966 * active switch. 967 */ 968 char cycling_changeover; 969 970 /* A temporary flag, which is used during the processing of 971 * a SACK to estimate the causative TSN(s)'s group. 972 */ 973 char cacc_saw_newack; 974 } cacc; 975 976 struct { 977 __u16 pmtu; 978 __u16 probe_size; 979 __u16 probe_high; 980 __u8 probe_count; 981 __u8 state; 982 } pl; /* plpmtud related */ 983 984 /* 64-bit random number sent with heartbeat. */ 985 __u64 hb_nonce; 986 987 struct rcu_head rcu; 988 }; 989 990 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *, 991 gfp_t); 992 void sctp_transport_set_owner(struct sctp_transport *, 993 struct sctp_association *); 994 void sctp_transport_route(struct sctp_transport *, union sctp_addr *, 995 struct sctp_sock *); 996 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk); 997 void sctp_transport_free(struct sctp_transport *); 998 void sctp_transport_reset_t3_rtx(struct sctp_transport *); 999 void sctp_transport_reset_hb_timer(struct sctp_transport *); 1000 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport); 1001 void sctp_transport_reset_probe_timer(struct sctp_transport *transport); 1002 void sctp_transport_reset_raise_timer(struct sctp_transport *transport); 1003 int sctp_transport_hold(struct sctp_transport *); 1004 void sctp_transport_put(struct sctp_transport *); 1005 void sctp_transport_update_rto(struct sctp_transport *, __u32); 1006 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32); 1007 void sctp_transport_lower_cwnd(struct sctp_transport *t, 1008 enum sctp_lower_cwnd reason); 1009 void sctp_transport_burst_limited(struct sctp_transport *); 1010 void sctp_transport_burst_reset(struct sctp_transport *); 1011 unsigned long sctp_transport_timeout(struct sctp_transport *); 1012 void sctp_transport_reset(struct sctp_transport *t); 1013 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu); 1014 void sctp_transport_immediate_rtx(struct sctp_transport *); 1015 void sctp_transport_dst_release(struct sctp_transport *t); 1016 void sctp_transport_dst_confirm(struct sctp_transport *t); 1017 void sctp_transport_pl_send(struct sctp_transport *t); 1018 bool sctp_transport_pl_recv(struct sctp_transport *t); 1019 1020 1021 /* This is the structure we use to queue packets as they come into 1022 * SCTP. We write packets to it and read chunks from it. 1023 */ 1024 struct sctp_inq { 1025 /* This is actually a queue of sctp_chunk each 1026 * containing a partially decoded packet. 1027 */ 1028 struct list_head in_chunk_list; 1029 /* This is the packet which is currently off the in queue and is 1030 * being worked on through the inbound chunk processing. 1031 */ 1032 struct sctp_chunk *in_progress; 1033 1034 /* This is the delayed task to finish delivering inbound 1035 * messages. 1036 */ 1037 struct work_struct immediate; 1038 }; 1039 1040 void sctp_inq_init(struct sctp_inq *); 1041 void sctp_inq_free(struct sctp_inq *); 1042 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet); 1043 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *); 1044 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *); 1045 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t); 1046 1047 /* This is the structure we use to hold outbound chunks. You push 1048 * chunks in and they automatically pop out the other end as bundled 1049 * packets (it calls (*output_handler)()). 1050 * 1051 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1, 1052 * and 8.2 of the v13 draft. 1053 * 1054 * It handles retransmissions. The connection to the timeout portion 1055 * of the state machine is through sctp_..._timeout() and timeout_handler. 1056 * 1057 * If you feed it SACKs, it will eat them. 1058 * 1059 * If you give it big chunks, it will fragment them. 1060 * 1061 * It assigns TSN's to data chunks. This happens at the last possible 1062 * instant before transmission. 1063 * 1064 * When free()'d, it empties itself out via output_handler(). 1065 */ 1066 struct sctp_outq { 1067 struct sctp_association *asoc; 1068 1069 /* Data pending that has never been transmitted. */ 1070 struct list_head out_chunk_list; 1071 1072 /* Stream scheduler being used */ 1073 const struct sctp_sched_ops *sched; 1074 1075 unsigned int out_qlen; /* Total length of queued data chunks. */ 1076 1077 /* Error of send failed, may used in SCTP_SEND_FAILED event. */ 1078 unsigned int error; 1079 1080 /* These are control chunks we want to send. */ 1081 struct list_head control_chunk_list; 1082 1083 /* These are chunks that have been sacked but are above the 1084 * CTSN, or cumulative tsn ack point. 1085 */ 1086 struct list_head sacked; 1087 1088 /* Put chunks on this list to schedule them for 1089 * retransmission. 1090 */ 1091 struct list_head retransmit; 1092 1093 /* Put chunks on this list to save them for FWD TSN processing as 1094 * they were abandoned. 1095 */ 1096 struct list_head abandoned; 1097 1098 /* How many unackd bytes do we have in-flight? */ 1099 __u32 outstanding_bytes; 1100 1101 /* Are we doing fast-rtx on this queue */ 1102 char fast_rtx; 1103 1104 /* Corked? */ 1105 char cork; 1106 }; 1107 1108 void sctp_outq_init(struct sctp_association *, struct sctp_outq *); 1109 void sctp_outq_teardown(struct sctp_outq *); 1110 void sctp_outq_free(struct sctp_outq*); 1111 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t); 1112 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *); 1113 int sctp_outq_is_empty(const struct sctp_outq *); 1114 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport, 1115 enum sctp_retransmit_reason reason); 1116 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8); 1117 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp); 1118 void sctp_prsctp_prune(struct sctp_association *asoc, 1119 struct sctp_sndrcvinfo *sinfo, int msg_len); 1120 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn); 1121 /* Uncork and flush an outqueue. */ 1122 static inline void sctp_outq_cork(struct sctp_outq *q) 1123 { 1124 q->cork = 1; 1125 } 1126 1127 /* SCTP skb control block. 1128 * sctp_input_cb is currently used on rx and sock rx queue 1129 */ 1130 struct sctp_input_cb { 1131 union { 1132 struct inet_skb_parm h4; 1133 #if IS_ENABLED(CONFIG_IPV6) 1134 struct inet6_skb_parm h6; 1135 #endif 1136 } header; 1137 struct sctp_chunk *chunk; 1138 struct sctp_af *af; 1139 __be16 encap_port; 1140 }; 1141 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0])) 1142 1143 struct sctp_output_cb { 1144 struct sk_buff *last; 1145 }; 1146 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0])) 1147 1148 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb) 1149 { 1150 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; 1151 1152 return chunk->head_skb ? : skb; 1153 } 1154 1155 /* These bind address data fields common between endpoints and associations */ 1156 struct sctp_bind_addr { 1157 1158 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1159 * 1160 * SCTP Port: The local SCTP port number the endpoint is 1161 * bound to. 1162 */ 1163 __u16 port; 1164 1165 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1166 * 1167 * Address List: The list of IP addresses that this instance 1168 * has bound. This information is passed to one's 1169 * peer(s) in INIT and INIT ACK chunks. 1170 */ 1171 struct list_head address_list; 1172 }; 1173 1174 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port); 1175 void sctp_bind_addr_free(struct sctp_bind_addr *); 1176 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest, 1177 const struct sctp_bind_addr *src, 1178 enum sctp_scope scope, gfp_t gfp, 1179 int flags); 1180 int sctp_bind_addr_dup(struct sctp_bind_addr *dest, 1181 const struct sctp_bind_addr *src, 1182 gfp_t gfp); 1183 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *, 1184 int new_size, __u8 addr_state, gfp_t gfp); 1185 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *); 1186 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *, 1187 struct sctp_sock *); 1188 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *, 1189 struct sctp_sock *, struct sctp_sock *); 1190 int sctp_bind_addr_state(const struct sctp_bind_addr *bp, 1191 const union sctp_addr *addr); 1192 int sctp_bind_addrs_check(struct sctp_sock *sp, 1193 struct sctp_sock *sp2, int cnt2); 1194 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp, 1195 const union sctp_addr *addrs, 1196 int addrcnt, 1197 struct sctp_sock *opt); 1198 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp, 1199 int *addrs_len, 1200 gfp_t gfp); 1201 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len, 1202 __u16 port, gfp_t gfp); 1203 1204 enum sctp_scope sctp_scope(const union sctp_addr *addr); 1205 int sctp_in_scope(struct net *net, const union sctp_addr *addr, 1206 const enum sctp_scope scope); 1207 int sctp_is_any(struct sock *sk, const union sctp_addr *addr); 1208 int sctp_is_ep_boundall(struct sock *sk); 1209 1210 1211 /* What type of endpoint? */ 1212 enum sctp_endpoint_type { 1213 SCTP_EP_TYPE_SOCKET, 1214 SCTP_EP_TYPE_ASSOCIATION, 1215 }; 1216 1217 /* 1218 * A common base class to bridge the implementation view of a 1219 * socket (usually listening) endpoint versus an association's 1220 * local endpoint. 1221 * This common structure is useful for several purposes: 1222 * 1) Common interface for lookup routines. 1223 * a) Subfunctions work for either endpoint or association 1224 * b) Single interface to lookup allows hiding the lookup lock rather 1225 * than acquiring it externally. 1226 * 2) Common interface for the inbound chunk handling/state machine. 1227 * 3) Common object handling routines for reference counting, etc. 1228 * 4) Disentangle association lookup from endpoint lookup, where we 1229 * do not have to find our endpoint to find our association. 1230 * 1231 */ 1232 1233 struct sctp_ep_common { 1234 /* Runtime type information. What kind of endpoint is this? */ 1235 enum sctp_endpoint_type type; 1236 1237 /* Some fields to help us manage this object. 1238 * refcnt - Reference count access to this object. 1239 * dead - Do not attempt to use this object. 1240 */ 1241 refcount_t refcnt; 1242 bool dead; 1243 1244 /* What socket does this endpoint belong to? */ 1245 struct sock *sk; 1246 1247 /* Cache netns and it won't change once set */ 1248 struct net *net; 1249 1250 /* This is where we receive inbound chunks. */ 1251 struct sctp_inq inqueue; 1252 1253 /* This substructure includes the defining parameters of the 1254 * endpoint: 1255 * bind_addr.port is our shared port number. 1256 * bind_addr.address_list is our set of local IP addresses. 1257 */ 1258 struct sctp_bind_addr bind_addr; 1259 }; 1260 1261 1262 /* RFC Section 1.4 Key Terms 1263 * 1264 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a 1265 * multi-homed host, an SCTP endpoint is represented to its peers as a 1266 * combination of a set of eligible destination transport addresses to 1267 * which SCTP packets can be sent and a set of eligible source 1268 * transport addresses from which SCTP packets can be received. 1269 * All transport addresses used by an SCTP endpoint must use the 1270 * same port number, but can use multiple IP addresses. A transport 1271 * address used by an SCTP endpoint must not be used by another 1272 * SCTP endpoint. In other words, a transport address is unique 1273 * to an SCTP endpoint. 1274 * 1275 * From an implementation perspective, each socket has one of these. 1276 * A TCP-style socket will have exactly one association on one of 1277 * these. An UDP-style socket will have multiple associations hanging 1278 * off one of these. 1279 */ 1280 1281 struct sctp_endpoint { 1282 /* Common substructure for endpoint and association. */ 1283 struct sctp_ep_common base; 1284 1285 /* Fields to help us manage our entries in the hash tables. */ 1286 struct hlist_node node; 1287 int hashent; 1288 1289 /* Associations: A list of current associations and mappings 1290 * to the data consumers for each association. This 1291 * may be in the form of a hash table or other 1292 * implementation dependent structure. The data 1293 * consumers may be process identification 1294 * information such as file descriptors, named pipe 1295 * pointer, or table pointers dependent on how SCTP 1296 * is implemented. 1297 */ 1298 /* This is really a list of struct sctp_association entries. */ 1299 struct list_head asocs; 1300 1301 /* Cookie authentication key used by this endpoint */ 1302 struct hmac_sha256_key cookie_auth_key; 1303 1304 /* sendbuf acct. policy. */ 1305 __u32 sndbuf_policy; 1306 1307 /* rcvbuf acct. policy. */ 1308 __u32 rcvbuf_policy; 1309 1310 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */ 1311 struct sctp_hmac_algo_param *auth_hmacs_list; 1312 1313 /* SCTP-AUTH: chunks to authenticate encoded into parameter */ 1314 struct sctp_chunks_param *auth_chunk_list; 1315 1316 /* SCTP-AUTH: endpoint shared keys */ 1317 struct list_head endpoint_shared_keys; 1318 __u16 active_key_id; 1319 __u8 ecn_enable:1, 1320 auth_enable:1, 1321 intl_enable:1, 1322 prsctp_enable:1, 1323 asconf_enable:1, 1324 reconf_enable:1; 1325 1326 __u8 strreset_enable; 1327 struct rcu_head rcu; 1328 }; 1329 1330 /* Recover the outer endpoint structure. */ 1331 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base) 1332 { 1333 struct sctp_endpoint *ep; 1334 1335 ep = container_of(base, struct sctp_endpoint, base); 1336 return ep; 1337 } 1338 1339 /* These are function signatures for manipulating endpoints. */ 1340 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t); 1341 void sctp_endpoint_free(struct sctp_endpoint *); 1342 void sctp_endpoint_put(struct sctp_endpoint *); 1343 int sctp_endpoint_hold(struct sctp_endpoint *ep); 1344 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *); 1345 struct sctp_association *sctp_endpoint_lookup_assoc( 1346 const struct sctp_endpoint *ep, 1347 const union sctp_addr *paddr, 1348 struct sctp_transport **); 1349 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep, 1350 const union sctp_addr *paddr); 1351 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *ep, 1352 struct net *net, 1353 const union sctp_addr *laddr, 1354 int dif, int sdif); 1355 bool sctp_has_association(struct net *net, const union sctp_addr *laddr, 1356 const union sctp_addr *paddr, int dif, int sdif); 1357 1358 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep, 1359 const struct sctp_association *asoc, 1360 enum sctp_cid cid, struct sctp_init_chunk *peer_init, 1361 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk); 1362 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk, 1363 const union sctp_addr *peer, 1364 struct sctp_init_chunk *init, gfp_t gfp); 1365 __u32 sctp_generate_tag(const struct sctp_endpoint *); 1366 __u32 sctp_generate_tsn(const struct sctp_endpoint *); 1367 1368 struct sctp_inithdr_host { 1369 __u32 init_tag; 1370 __u32 a_rwnd; 1371 __u16 num_outbound_streams; 1372 __u16 num_inbound_streams; 1373 __u32 initial_tsn; 1374 }; 1375 1376 struct sctp_stream_priorities { 1377 /* List of priorities scheduled */ 1378 struct list_head prio_sched; 1379 /* List of streams scheduled */ 1380 struct list_head active; 1381 /* The next stream in line */ 1382 struct sctp_stream_out_ext *next; 1383 __u16 prio; 1384 __u16 users; 1385 }; 1386 1387 struct sctp_stream_out_ext { 1388 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 1389 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 1390 struct list_head outq; /* chunks enqueued by this stream */ 1391 union { 1392 struct { 1393 /* Scheduled streams list */ 1394 struct list_head prio_list; 1395 struct sctp_stream_priorities *prio_head; 1396 }; 1397 /* Fields used by RR scheduler */ 1398 struct { 1399 struct list_head rr_list; 1400 }; 1401 struct { 1402 struct list_head fc_list; 1403 __u32 fc_length; 1404 __u16 fc_weight; 1405 }; 1406 }; 1407 }; 1408 1409 struct sctp_stream_out { 1410 union { 1411 __u32 mid; 1412 __u16 ssn; 1413 }; 1414 __u32 mid_uo; 1415 struct sctp_stream_out_ext *ext; 1416 __u8 state; 1417 }; 1418 1419 struct sctp_stream_in { 1420 union { 1421 __u32 mid; 1422 __u16 ssn; 1423 }; 1424 __u32 mid_uo; 1425 __u32 fsn; 1426 __u32 fsn_uo; 1427 char pd_mode; 1428 char pd_mode_uo; 1429 }; 1430 1431 struct sctp_stream { 1432 GENRADIX(struct sctp_stream_out) out; 1433 GENRADIX(struct sctp_stream_in) in; 1434 1435 __u16 outcnt; 1436 __u16 incnt; 1437 /* Current stream being sent, if any */ 1438 struct sctp_stream_out *out_curr; 1439 union { 1440 /* Fields used by priority scheduler */ 1441 struct { 1442 /* List of priorities scheduled */ 1443 struct list_head prio_list; 1444 }; 1445 /* Fields used by RR scheduler */ 1446 struct { 1447 /* List of streams scheduled */ 1448 struct list_head rr_list; 1449 /* The next stream in line */ 1450 struct sctp_stream_out_ext *rr_next; 1451 }; 1452 struct { 1453 struct list_head fc_list; 1454 }; 1455 }; 1456 struct sctp_stream_interleave *si; 1457 }; 1458 1459 static inline struct sctp_stream_out *sctp_stream_out( 1460 struct sctp_stream *stream, 1461 __u16 sid) 1462 { 1463 return genradix_ptr(&stream->out, sid); 1464 } 1465 1466 static inline struct sctp_stream_in *sctp_stream_in( 1467 struct sctp_stream *stream, 1468 __u16 sid) 1469 { 1470 return genradix_ptr(&stream->in, sid); 1471 } 1472 1473 #define SCTP_SO(s, i) sctp_stream_out((s), (i)) 1474 #define SCTP_SI(s, i) sctp_stream_in((s), (i)) 1475 1476 #define SCTP_STREAM_CLOSED 0x00 1477 #define SCTP_STREAM_OPEN 0x01 1478 1479 static inline __u16 sctp_datachk_len(const struct sctp_stream *stream) 1480 { 1481 return stream->si->data_chunk_len; 1482 } 1483 1484 static inline __u16 sctp_datahdr_len(const struct sctp_stream *stream) 1485 { 1486 return stream->si->data_chunk_len - sizeof(struct sctp_chunkhdr); 1487 } 1488 1489 static inline __u16 sctp_ftsnchk_len(const struct sctp_stream *stream) 1490 { 1491 return stream->si->ftsn_chunk_len; 1492 } 1493 1494 static inline __u16 sctp_ftsnhdr_len(const struct sctp_stream *stream) 1495 { 1496 return stream->si->ftsn_chunk_len - sizeof(struct sctp_chunkhdr); 1497 } 1498 1499 /* SCTP_GET_ASSOC_STATS counters */ 1500 struct sctp_priv_assoc_stats { 1501 /* Maximum observed rto in the association during subsequent 1502 * observations. Value is set to 0 if no RTO measurement took place 1503 * The transport where the max_rto was observed is returned in 1504 * obs_rto_ipaddr 1505 */ 1506 struct sockaddr_storage obs_rto_ipaddr; 1507 __u64 max_obs_rto; 1508 /* Total In and Out SACKs received and sent */ 1509 __u64 isacks; 1510 __u64 osacks; 1511 /* Total In and Out packets received and sent */ 1512 __u64 opackets; 1513 __u64 ipackets; 1514 /* Total retransmitted chunks */ 1515 __u64 rtxchunks; 1516 /* TSN received > next expected */ 1517 __u64 outofseqtsns; 1518 /* Duplicate Chunks received */ 1519 __u64 idupchunks; 1520 /* Gap Ack Blocks received */ 1521 __u64 gapcnt; 1522 /* Unordered data chunks sent and received */ 1523 __u64 ouodchunks; 1524 __u64 iuodchunks; 1525 /* Ordered data chunks sent and received */ 1526 __u64 oodchunks; 1527 __u64 iodchunks; 1528 /* Control chunks sent and received */ 1529 __u64 octrlchunks; 1530 __u64 ictrlchunks; 1531 }; 1532 1533 /* RFC2960 1534 * 1535 * 12. Recommended Transmission Control Block (TCB) Parameters 1536 * 1537 * This section details a recommended set of parameters that should 1538 * be contained within the TCB for an implementation. This section is 1539 * for illustrative purposes and should not be deemed as requirements 1540 * on an implementation or as an exhaustive list of all parameters 1541 * inside an SCTP TCB. Each implementation may need its own additional 1542 * parameters for optimization. 1543 */ 1544 1545 1546 /* Here we have information about each individual association. */ 1547 struct sctp_association { 1548 1549 /* A base structure common to endpoint and association. 1550 * In this context, it represents the associations's view 1551 * of the local endpoint of the association. 1552 */ 1553 struct sctp_ep_common base; 1554 1555 /* Associations on the same socket. */ 1556 struct list_head asocs; 1557 1558 /* association id. */ 1559 sctp_assoc_t assoc_id; 1560 1561 /* This is our parent endpoint. */ 1562 struct sctp_endpoint *ep; 1563 1564 /* These are those association elements needed in the cookie. */ 1565 struct sctp_cookie c; 1566 1567 /* This is all information about our peer. */ 1568 struct { 1569 /* transport_addr_list 1570 * 1571 * Peer : A list of SCTP transport addresses that the 1572 * Transport : peer is bound to. This information is derived 1573 * Address : from the INIT or INIT ACK and is used to 1574 * List : associate an inbound packet with a given 1575 * : association. Normally this information is 1576 * : hashed or keyed for quick lookup and access 1577 * : of the TCB. 1578 * : The list is also initialized with the list 1579 * : of addresses passed with the sctp_connectx() 1580 * : call. 1581 * 1582 * It is a list of SCTP_transport's. 1583 */ 1584 struct list_head transport_addr_list; 1585 1586 /* rwnd 1587 * 1588 * Peer Rwnd : Current calculated value of the peer's rwnd. 1589 */ 1590 __u32 rwnd; 1591 1592 /* transport_count 1593 * 1594 * Peer : A count of the number of peer addresses 1595 * Transport : in the Peer Transport Address List. 1596 * Address : 1597 * Count : 1598 */ 1599 __u16 transport_count; 1600 1601 /* port 1602 * The transport layer port number. 1603 */ 1604 __u16 port; 1605 1606 /* primary_path 1607 * 1608 * Primary : This is the current primary destination 1609 * Path : transport address of the peer endpoint. It 1610 * : may also specify a source transport address 1611 * : on this endpoint. 1612 * 1613 * All of these paths live on transport_addr_list. 1614 * 1615 * At the bakeoffs, we discovered that the intent of 1616 * primaryPath is that it only changes when the ULP 1617 * asks to have it changed. We add the activePath to 1618 * designate the connection we are currently using to 1619 * transmit new data and most control chunks. 1620 */ 1621 struct sctp_transport *primary_path; 1622 1623 /* Cache the primary path address here, when we 1624 * need a an address for msg_name. 1625 */ 1626 union sctp_addr primary_addr; 1627 1628 /* active_path 1629 * The path that we are currently using to 1630 * transmit new data and most control chunks. 1631 */ 1632 struct sctp_transport *active_path; 1633 1634 /* retran_path 1635 * 1636 * RFC2960 6.4 Multi-homed SCTP Endpoints 1637 * ... 1638 * Furthermore, when its peer is multi-homed, an 1639 * endpoint SHOULD try to retransmit a chunk to an 1640 * active destination transport address that is 1641 * different from the last destination address to 1642 * which the DATA chunk was sent. 1643 */ 1644 struct sctp_transport *retran_path; 1645 1646 /* Pointer to last transport I have sent on. */ 1647 struct sctp_transport *last_sent_to; 1648 1649 /* This is the last transport I have received DATA on. */ 1650 struct sctp_transport *last_data_from; 1651 1652 /* 1653 * Mapping An array of bits or bytes indicating which out of 1654 * Array order TSN's have been received (relative to the 1655 * Last Rcvd TSN). If no gaps exist, i.e. no out of 1656 * order packets have been received, this array 1657 * will be set to all zero. This structure may be 1658 * in the form of a circular buffer or bit array. 1659 * 1660 * Last Rcvd : This is the last TSN received in 1661 * TSN : sequence. This value is set initially by 1662 * : taking the peer's Initial TSN, received in 1663 * : the INIT or INIT ACK chunk, and subtracting 1664 * : one from it. 1665 * 1666 * Throughout most of the specification this is called the 1667 * "Cumulative TSN ACK Point". In this case, we 1668 * ignore the advice in 12.2 in favour of the term 1669 * used in the bulk of the text. This value is hidden 1670 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn(). 1671 */ 1672 struct sctp_tsnmap tsn_map; 1673 1674 /* This mask is used to disable sending the ASCONF chunk 1675 * with specified parameter to peer. 1676 */ 1677 __be16 addip_disabled_mask; 1678 1679 /* These are capabilities which our peer advertised. */ 1680 __u16 ecn_capable:1, /* Can peer do ECN? */ 1681 ipv4_address:1, /* Peer understands IPv4 addresses? */ 1682 ipv6_address:1, /* Peer understands IPv6 addresses? */ 1683 asconf_capable:1, /* Does peer support ADDIP? */ 1684 prsctp_capable:1, /* Can peer do PR-SCTP? */ 1685 reconf_capable:1, /* Can peer do RE-CONFIG? */ 1686 intl_capable:1, /* Can peer do INTERLEAVE */ 1687 auth_capable:1, /* Is peer doing SCTP-AUTH? */ 1688 /* sack_needed: 1689 * This flag indicates if the next received 1690 * packet is to be responded to with a 1691 * SACK. This is initialized to 0. When a packet 1692 * is received sack_cnt is incremented. If this value 1693 * reaches 2 or more, a SACK is sent and the 1694 * value is reset to 0. Note: This is used only 1695 * when no DATA chunks are received out of 1696 * order. When DATA chunks are out of order, 1697 * SACK's are not delayed (see Section 6). 1698 */ 1699 sack_needed:1, /* Do we need to sack the peer? */ 1700 sack_generation:1, 1701 zero_window_announced:1; 1702 1703 __u32 sack_cnt; 1704 1705 __u32 adaptation_ind; /* Adaptation Code point. */ 1706 1707 struct sctp_inithdr_host i; 1708 void *cookie; 1709 int cookie_len; 1710 1711 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. 1712 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the 1713 * Initial TSN Value minus 1 1714 */ 1715 __u32 addip_serial; 1716 1717 /* SCTP-AUTH: We need to know pears random number, hmac list 1718 * and authenticated chunk list. All that is part of the 1719 * cookie and these are just pointers to those locations 1720 */ 1721 struct sctp_random_param *peer_random; 1722 struct sctp_chunks_param *peer_chunks; 1723 struct sctp_hmac_algo_param *peer_hmacs; 1724 } peer; 1725 1726 /* State : A state variable indicating what state the 1727 * : association is in, i.e. COOKIE-WAIT, 1728 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING, 1729 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT. 1730 * 1731 * Note: No "CLOSED" state is illustrated since if a 1732 * association is "CLOSED" its TCB SHOULD be removed. 1733 * 1734 * In this implementation we DO have a CLOSED 1735 * state which is used during initiation and shutdown. 1736 * 1737 * State takes values from SCTP_STATE_*. 1738 */ 1739 enum sctp_state state; 1740 1741 /* Overall : The overall association error count. 1742 * Error Count : [Clear this any time I get something.] 1743 */ 1744 int overall_error_count; 1745 1746 /* The cookie life I award for any cookie. */ 1747 ktime_t cookie_life; 1748 1749 /* These are the association's initial, max, and min RTO values. 1750 * These values will be initialized by system defaults, but can 1751 * be modified via the SCTP_RTOINFO socket option. 1752 */ 1753 unsigned long rto_initial; 1754 unsigned long rto_max; 1755 unsigned long rto_min; 1756 1757 /* Maximum number of new data packets that can be sent in a burst. */ 1758 int max_burst; 1759 1760 /* This is the max_retrans value for the association. This value will 1761 * be initialized from system defaults, but can be 1762 * modified by the SCTP_ASSOCINFO socket option. 1763 */ 1764 int max_retrans; 1765 1766 /* This is the partially failed retrans value for the transport 1767 * and will be initialized from the assocs value. This can be 1768 * changed using the SCTP_PEER_ADDR_THLDS socket option 1769 */ 1770 __u16 pf_retrans; 1771 /* Used for primary path switchover. */ 1772 __u16 ps_retrans; 1773 1774 /* Maximum number of times the endpoint will retransmit INIT */ 1775 __u16 max_init_attempts; 1776 1777 /* How many times have we resent an INIT? */ 1778 __u16 init_retries; 1779 1780 /* The largest timeout or RTO value to use in attempting an INIT */ 1781 unsigned long max_init_timeo; 1782 1783 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 1784 * the destination address every heartbeat interval. This value 1785 * will be inherited by all new transports. 1786 */ 1787 unsigned long hbinterval; 1788 unsigned long probe_interval; 1789 1790 __be16 encap_port; 1791 1792 /* This is the max_retrans value for new transports in the 1793 * association. 1794 */ 1795 __u16 pathmaxrxt; 1796 1797 __u32 flowlabel; 1798 __u8 dscp; 1799 1800 /* Flag that path mtu update is pending */ 1801 __u8 pmtu_pending; 1802 1803 /* Association : The smallest PMTU discovered for all of the 1804 * PMTU : peer's transport addresses. 1805 */ 1806 __u32 pathmtu; 1807 1808 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 1809 __u32 param_flags; 1810 1811 __u32 sackfreq; 1812 /* SACK delay timeout */ 1813 unsigned long sackdelay; 1814 1815 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES]; 1816 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES]; 1817 1818 /* Transport to which SHUTDOWN chunk was last sent. */ 1819 struct sctp_transport *shutdown_last_sent_to; 1820 1821 /* Transport to which INIT chunk was last sent. */ 1822 struct sctp_transport *init_last_sent_to; 1823 1824 /* How many times have we resent a SHUTDOWN */ 1825 int shutdown_retries; 1826 1827 /* Next TSN : The next TSN number to be assigned to a new 1828 * : DATA chunk. This is sent in the INIT or INIT 1829 * : ACK chunk to the peer and incremented each 1830 * : time a DATA chunk is assigned a TSN 1831 * : (normally just prior to transmit or during 1832 * : fragmentation). 1833 */ 1834 __u32 next_tsn; 1835 1836 /* 1837 * Last Rcvd : This is the last TSN received in sequence. This value 1838 * TSN : is set initially by taking the peer's Initial TSN, 1839 * : received in the INIT or INIT ACK chunk, and 1840 * : subtracting one from it. 1841 * 1842 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point. 1843 */ 1844 1845 __u32 ctsn_ack_point; 1846 1847 /* PR-SCTP Advanced.Peer.Ack.Point */ 1848 __u32 adv_peer_ack_point; 1849 1850 /* Highest TSN that is acknowledged by incoming SACKs. */ 1851 __u32 highest_sacked; 1852 1853 /* TSN marking the fast recovery exit point */ 1854 __u32 fast_recovery_exit; 1855 1856 /* Flag to track the current fast recovery state */ 1857 __u8 fast_recovery; 1858 1859 /* The number of unacknowledged data chunks. Reported through 1860 * the SCTP_STATUS sockopt. 1861 */ 1862 __u16 unack_data; 1863 1864 /* The total number of data chunks that we've had to retransmit 1865 * as the result of a T3 timer expiration 1866 */ 1867 __u32 rtx_data_chunks; 1868 1869 /* This is the association's receive buffer space. This value is used 1870 * to set a_rwnd field in an INIT or a SACK chunk. 1871 */ 1872 __u32 rwnd; 1873 1874 /* This is the last advertised value of rwnd over a SACK chunk. */ 1875 __u32 a_rwnd; 1876 1877 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed 1878 * to slop over a maximum of the association's frag_point. 1879 */ 1880 __u32 rwnd_over; 1881 1882 /* Keeps treack of rwnd pressure. This happens when we have 1883 * a window, but not receive buffer (i.e small packets). This one 1884 * is releases slowly (1 PMTU at a time ). 1885 */ 1886 __u32 rwnd_press; 1887 1888 /* This is the sndbuf size in use for the association. 1889 * This corresponds to the sndbuf size for the association, 1890 * as specified in the sk->sndbuf. 1891 */ 1892 int sndbuf_used; 1893 1894 /* This is the amount of memory that this association has allocated 1895 * in the receive path at any given time. 1896 */ 1897 atomic_t rmem_alloc; 1898 1899 /* This is the wait queue head for send requests waiting on 1900 * the association sndbuf space. 1901 */ 1902 wait_queue_head_t wait; 1903 1904 /* The message size at which SCTP fragmentation will occur. */ 1905 __u32 frag_point; 1906 __u32 user_frag; 1907 1908 /* Counter used to count INIT errors. */ 1909 int init_err_counter; 1910 1911 /* Count the number of INIT cycles (for doubling timeout). */ 1912 int init_cycle; 1913 1914 /* Default send parameters. */ 1915 __u16 default_stream; 1916 __u16 default_flags; 1917 __u32 default_ppid; 1918 __u32 default_context; 1919 __u32 default_timetolive; 1920 1921 /* Default receive parameters */ 1922 __u32 default_rcv_context; 1923 1924 /* Stream arrays */ 1925 struct sctp_stream stream; 1926 1927 /* All outbound chunks go through this structure. */ 1928 struct sctp_outq outqueue; 1929 1930 /* A smart pipe that will handle reordering and fragmentation, 1931 * as well as handle passing events up to the ULP. 1932 */ 1933 struct sctp_ulpq ulpq; 1934 1935 /* Last TSN that caused an ECNE Chunk to be sent. */ 1936 __u32 last_ecne_tsn; 1937 1938 /* Last TSN that caused a CWR Chunk to be sent. */ 1939 __u32 last_cwr_tsn; 1940 1941 /* How many duplicated TSNs have we seen? */ 1942 int numduptsns; 1943 1944 /* These are to support 1945 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses 1946 * and Enforcement of Flow and Message Limits" 1947 * <draft-ietf-tsvwg-addip-sctp-02.txt> 1948 * or "ADDIP" for short. 1949 */ 1950 1951 1952 1953 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1954 * 1955 * R1) One and only one ASCONF Chunk MAY be in transit and 1956 * unacknowledged at any one time. If a sender, after sending 1957 * an ASCONF chunk, decides it needs to transfer another 1958 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1959 * returns from the previous ASCONF Chunk before sending a 1960 * subsequent ASCONF. Note this restriction binds each side, 1961 * so at any time two ASCONF may be in-transit on any given 1962 * association (one sent from each endpoint). 1963 * 1964 * [This is our one-and-only-one ASCONF in flight. If we do 1965 * not have an ASCONF in flight, this is NULL.] 1966 */ 1967 struct sctp_chunk *addip_last_asconf; 1968 1969 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk. 1970 * 1971 * This is needed to implement items E1 - E4 of the updated 1972 * spec. Here is the justification: 1973 * 1974 * Since the peer may bundle multiple ASCONF chunks toward us, 1975 * we now need the ability to cache multiple ACKs. The section 1976 * describes in detail how they are cached and cleaned up. 1977 */ 1978 struct list_head asconf_ack_list; 1979 1980 /* These ASCONF chunks are waiting to be sent. 1981 * 1982 * These chunks can't be pushed to outqueue until receiving 1983 * ASCONF_ACK for the previous ASCONF indicated by 1984 * addip_last_asconf, so as to guarantee that only one ASCONF 1985 * is in flight at any time. 1986 * 1987 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1988 * 1989 * In defining the ASCONF Chunk transfer procedures, it is 1990 * essential that these transfers MUST NOT cause congestion 1991 * within the network. To achieve this, we place these 1992 * restrictions on the transfer of ASCONF Chunks: 1993 * 1994 * R1) One and only one ASCONF Chunk MAY be in transit and 1995 * unacknowledged at any one time. If a sender, after sending 1996 * an ASCONF chunk, decides it needs to transfer another 1997 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1998 * returns from the previous ASCONF Chunk before sending a 1999 * subsequent ASCONF. Note this restriction binds each side, 2000 * so at any time two ASCONF may be in-transit on any given 2001 * association (one sent from each endpoint). 2002 * 2003 * 2004 * [I really think this is EXACTLY the sort of intelligence 2005 * which already resides in sctp_outq. Please move this 2006 * queue and its supporting logic down there. --piggy] 2007 */ 2008 struct list_head addip_chunk_list; 2009 2010 /* ADDIP Section 4.1 ASCONF Chunk Procedures 2011 * 2012 * A2) A serial number should be assigned to the Chunk. The 2013 * serial number SHOULD be a monotonically increasing 2014 * number. The serial number SHOULD be initialized at 2015 * the start of the association to the same value as the 2016 * Initial TSN and every time a new ASCONF chunk is created 2017 * it is incremented by one after assigning the serial number 2018 * to the newly created chunk. 2019 * 2020 * ADDIP 2021 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF) 2022 * 2023 * Serial Number : 32 bits (unsigned integer) 2024 * 2025 * This value represents a Serial Number for the ASCONF 2026 * Chunk. The valid range of Serial Number is from 0 to 2027 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0 2028 * after reaching 4294967295. 2029 */ 2030 __u32 addip_serial; 2031 int src_out_of_asoc_ok; 2032 union sctp_addr *asconf_addr_del_pending; 2033 struct sctp_transport *new_transport; 2034 2035 /* SCTP AUTH: list of the endpoint shared keys. These 2036 * keys are provided out of band by the user application 2037 * and can't change during the lifetime of the association 2038 */ 2039 struct list_head endpoint_shared_keys; 2040 2041 /* SCTP AUTH: 2042 * The current generated association shared key (secret) 2043 */ 2044 struct sctp_auth_bytes *asoc_shared_key; 2045 struct sctp_shared_key *shkey; 2046 2047 /* SCTP AUTH: hmac id of the first peer requested algorithm 2048 * that we support. 2049 */ 2050 __u16 default_hmac_id; 2051 2052 __u16 active_key_id; 2053 2054 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */ 2055 temp:1, /* Is it a temporary association? */ 2056 pf_expose:2, /* Expose pf state? */ 2057 force_delay:1; 2058 2059 __u8 strreset_enable; 2060 __u8 strreset_outstanding; /* request param count on the fly */ 2061 2062 __u32 strreset_outseq; /* Update after receiving response */ 2063 __u32 strreset_inseq; /* Update after receiving request */ 2064 __u32 strreset_result[2]; /* save the results of last 2 responses */ 2065 2066 struct sctp_chunk *strreset_chunk; /* save request chunk */ 2067 2068 struct sctp_priv_assoc_stats stats; 2069 2070 int sent_cnt_removable; 2071 2072 __u16 subscribe; 2073 2074 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 2075 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 2076 2077 /* Security identifiers from incoming (INIT). These are set by 2078 * security_sctp_assoc_request(). These will only be used by 2079 * SCTP TCP type sockets and peeled off connections as they 2080 * cause a new socket to be generated. security_sctp_sk_clone() 2081 * will then plug these into the new socket. 2082 */ 2083 2084 u32 secid; 2085 u32 peer_secid; 2086 2087 struct rcu_head rcu; 2088 }; 2089 2090 2091 /* An eyecatcher for determining if we are really looking at an 2092 * association data structure. 2093 */ 2094 enum { 2095 SCTP_ASSOC_EYECATCHER = 0xa550c123, 2096 }; 2097 2098 /* Recover the outer association structure. */ 2099 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base) 2100 { 2101 struct sctp_association *asoc; 2102 2103 asoc = container_of(base, struct sctp_association, base); 2104 return asoc; 2105 } 2106 2107 /* These are function signatures for manipulating associations. */ 2108 2109 2110 struct sctp_association * 2111 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk, 2112 enum sctp_scope scope, gfp_t gfp); 2113 void sctp_association_free(struct sctp_association *); 2114 void sctp_association_put(struct sctp_association *); 2115 void sctp_association_hold(struct sctp_association *); 2116 2117 struct sctp_transport *sctp_assoc_choose_alter_transport( 2118 struct sctp_association *, struct sctp_transport *); 2119 void sctp_assoc_update_retran_path(struct sctp_association *); 2120 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *, 2121 const union sctp_addr *); 2122 int sctp_assoc_lookup_laddr(struct sctp_association *asoc, 2123 const union sctp_addr *laddr); 2124 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *, 2125 const union sctp_addr *address, 2126 const gfp_t gfp, 2127 const int peer_state); 2128 void sctp_assoc_rm_peer(struct sctp_association *asoc, 2129 struct sctp_transport *peer); 2130 void sctp_assoc_control_transport(struct sctp_association *asoc, 2131 struct sctp_transport *transport, 2132 enum sctp_transport_cmd command, 2133 sctp_sn_error_t error); 2134 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32); 2135 void sctp_assoc_migrate(struct sctp_association *, struct sock *); 2136 int sctp_assoc_update(struct sctp_association *old, 2137 struct sctp_association *new); 2138 2139 __u32 sctp_association_get_next_tsn(struct sctp_association *); 2140 2141 void sctp_assoc_update_frag_point(struct sctp_association *asoc); 2142 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu); 2143 void sctp_assoc_sync_pmtu(struct sctp_association *asoc); 2144 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int); 2145 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int); 2146 void sctp_assoc_set_primary(struct sctp_association *, 2147 struct sctp_transport *); 2148 void sctp_assoc_del_nonprimary_peers(struct sctp_association *, 2149 struct sctp_transport *); 2150 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, 2151 enum sctp_scope scope, gfp_t gfp); 2152 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *, 2153 struct sctp_cookie*, 2154 gfp_t gfp); 2155 int sctp_assoc_set_id(struct sctp_association *, gfp_t); 2156 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc); 2157 struct sctp_chunk *sctp_assoc_lookup_asconf_ack( 2158 const struct sctp_association *asoc, 2159 __be32 serial); 2160 void sctp_asconf_queue_teardown(struct sctp_association *asoc); 2161 2162 int sctp_cmp_addr_exact(const union sctp_addr *ss1, 2163 const union sctp_addr *ss2); 2164 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc); 2165 2166 /* A convenience structure to parse out SCTP specific CMSGs. */ 2167 struct sctp_cmsgs { 2168 struct sctp_initmsg *init; 2169 struct sctp_sndrcvinfo *srinfo; 2170 struct sctp_sndinfo *sinfo; 2171 struct sctp_prinfo *prinfo; 2172 struct sctp_authinfo *authinfo; 2173 struct msghdr *addrs_msg; 2174 }; 2175 2176 /* Structure for tracking memory objects */ 2177 struct sctp_dbg_objcnt_entry { 2178 char *label; 2179 atomic_t *counter; 2180 }; 2181 2182 #endif /* __sctp_structs_h__ */ 2183