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 /* Fields after this point will be skipped on copies, like on accept 232 * and peeloff operations 233 */ 234 235 /* Receive to here while partial delivery is in effect. */ 236 struct sk_buff_head pd_lobby; 237 238 struct list_head auto_asconf_list; 239 int do_auto_asconf; 240 }; 241 242 #define sctp_sk(ptr) container_of_const(ptr, struct sctp_sock, inet.sk) 243 244 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp) 245 { 246 return (struct sock *)sp; 247 } 248 249 #if IS_ENABLED(CONFIG_IPV6) 250 struct sctp6_sock { 251 struct sctp_sock sctp; 252 struct ipv6_pinfo inet6; 253 }; 254 #endif /* CONFIG_IPV6 */ 255 256 257 /* This is our APPLICATION-SPECIFIC state cookie. 258 * THIS IS NOT DICTATED BY THE SPECIFICATION. 259 */ 260 /* These are the parts of an association which we send in the cookie. 261 * Most of these are straight out of: 262 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB) 263 * 264 */ 265 266 struct sctp_cookie { 267 268 /* My : Tag expected in every inbound packet and sent 269 * Verification: in the INIT or INIT ACK chunk. 270 * Tag : 271 */ 272 __u32 my_vtag; 273 274 /* Peer's : Tag expected in every outbound packet except 275 * Verification: in the INIT chunk. 276 * Tag : 277 */ 278 __u32 peer_vtag; 279 280 /* The rest of these are not from the spec, but really need to 281 * be in the cookie. 282 */ 283 284 /* My Tie Tag : Assist in discovering a restarting association. */ 285 __u32 my_ttag; 286 287 /* Peer's Tie Tag: Assist in discovering a restarting association. */ 288 __u32 peer_ttag; 289 290 /* When does this cookie expire? */ 291 ktime_t expiration; 292 293 /* Number of inbound/outbound streams which are set 294 * and negotiated during the INIT process. 295 */ 296 __u16 sinit_num_ostreams; 297 __u16 sinit_max_instreams; 298 299 /* This is the first sequence number I used. */ 300 __u32 initial_tsn; 301 302 /* This holds the originating address of the INIT packet. */ 303 union sctp_addr peer_addr; 304 305 /* IG Section 2.35.3 306 * Include the source port of the INIT-ACK 307 */ 308 __u16 my_port; 309 310 __u8 prsctp_capable; 311 312 /* Padding for future use */ 313 __u8 padding; 314 315 __u32 adaptation_ind; 316 317 __u8 auth_random[sizeof(struct sctp_paramhdr) + 318 SCTP_AUTH_RANDOM_LENGTH]; 319 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2]; 320 __u8 auth_chunks[sizeof(struct sctp_paramhdr) + SCTP_AUTH_MAX_CHUNKS]; 321 322 /* This is a shim for my peer's INIT packet, followed by 323 * a copy of the raw address list of the association. 324 * The length of the raw address list is saved in the 325 * raw_addr_list_len field, which will be used at the time when 326 * the association TCB is re-constructed from the cookie. 327 */ 328 __u32 raw_addr_list_len; 329 /* struct sctp_init_chunk peer_init[]; */ 330 }; 331 332 333 /* The format of our cookie that we send to our peer. */ 334 struct sctp_signed_cookie { 335 __u8 mac[SCTP_COOKIE_MAC_SIZE]; 336 __u32 __pad; /* force sctp_cookie alignment to 64 bits */ 337 struct sctp_cookie c; 338 } __packed; 339 340 /* This is another convenience type to allocate memory for address 341 * params for the maximum size and pass such structures around 342 * internally. 343 */ 344 union sctp_addr_param { 345 struct sctp_paramhdr p; 346 struct sctp_ipv4addr_param v4; 347 struct sctp_ipv6addr_param v6; 348 }; 349 350 /* A convenience type to allow walking through the various 351 * parameters and avoid casting all over the place. 352 */ 353 union sctp_params { 354 void *v; 355 struct sctp_paramhdr *p; 356 struct sctp_cookie_preserve_param *life; 357 struct sctp_hostname_param *dns; 358 struct sctp_cookie_param *cookie; 359 struct sctp_supported_addrs_param *sat; 360 struct sctp_ipv4addr_param *v4; 361 struct sctp_ipv6addr_param *v6; 362 union sctp_addr_param *addr; 363 struct sctp_adaptation_ind_param *aind; 364 struct sctp_supported_ext_param *ext; 365 struct sctp_random_param *random; 366 struct sctp_chunks_param *chunks; 367 struct sctp_hmac_algo_param *hmac_algo; 368 struct sctp_addip_param *addip; 369 }; 370 371 /* RFC 2960. Section 3.3.5 Heartbeat. 372 * Heartbeat Information: variable length 373 * The Sender-specific Heartbeat Info field should normally include 374 * information about the sender's current time when this HEARTBEAT 375 * chunk is sent and the destination transport address to which this 376 * HEARTBEAT is sent (see Section 8.3). 377 */ 378 struct sctp_sender_hb_info { 379 struct sctp_paramhdr param_hdr; 380 union sctp_addr daddr; 381 unsigned long sent_at; 382 __u64 hb_nonce; 383 __u32 probe_size; 384 }; 385 386 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt, 387 gfp_t gfp); 388 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid); 389 void sctp_stream_free(struct sctp_stream *stream); 390 void sctp_stream_clear(struct sctp_stream *stream); 391 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new); 392 393 /* What is the current SSN number for this stream? */ 394 #define sctp_ssn_peek(stream, type, sid) \ 395 (sctp_stream_##type((stream), (sid))->ssn) 396 397 /* Return the next SSN number for this stream. */ 398 #define sctp_ssn_next(stream, type, sid) \ 399 (sctp_stream_##type((stream), (sid))->ssn++) 400 401 /* Skip over this ssn and all below. */ 402 #define sctp_ssn_skip(stream, type, sid, ssn) \ 403 (sctp_stream_##type((stream), (sid))->ssn = ssn + 1) 404 405 /* What is the current MID number for this stream? */ 406 #define sctp_mid_peek(stream, type, sid) \ 407 (sctp_stream_##type((stream), (sid))->mid) 408 409 /* Return the next MID number for this stream. */ 410 #define sctp_mid_next(stream, type, sid) \ 411 (sctp_stream_##type((stream), (sid))->mid++) 412 413 /* Skip over this mid and all below. */ 414 #define sctp_mid_skip(stream, type, sid, mid) \ 415 (sctp_stream_##type((stream), (sid))->mid = mid + 1) 416 417 /* What is the current MID_uo number for this stream? */ 418 #define sctp_mid_uo_peek(stream, type, sid) \ 419 (sctp_stream_##type((stream), (sid))->mid_uo) 420 421 /* Return the next MID_uo number for this stream. */ 422 #define sctp_mid_uo_next(stream, type, sid) \ 423 (sctp_stream_##type((stream), (sid))->mid_uo++) 424 425 /* 426 * Pointers to address related SCTP functions. 427 * (i.e. things that depend on the address family.) 428 */ 429 struct sctp_af { 430 int (*sctp_xmit) (struct sk_buff *skb, 431 struct sctp_transport *); 432 int (*setsockopt) (struct sock *sk, 433 int level, 434 int optname, 435 sockptr_t optval, 436 unsigned int optlen); 437 int (*getsockopt) (struct sock *sk, 438 int level, 439 int optname, 440 char __user *optval, 441 int __user *optlen); 442 void (*get_dst) (struct sctp_transport *t, 443 union sctp_addr *saddr, 444 struct flowi *fl, 445 struct sock *sk); 446 void (*get_saddr) (struct sctp_sock *sk, 447 struct sctp_transport *t, 448 struct flowi *fl); 449 void (*copy_addrlist) (struct list_head *, 450 struct net_device *); 451 int (*cmp_addr) (const union sctp_addr *addr1, 452 const union sctp_addr *addr2); 453 void (*addr_copy) (union sctp_addr *dst, 454 union sctp_addr *src); 455 void (*from_skb) (union sctp_addr *, 456 struct sk_buff *skb, 457 int saddr); 458 void (*from_sk) (union sctp_addr *, 459 struct sock *sk); 460 bool (*from_addr_param) (union sctp_addr *, 461 union sctp_addr_param *, 462 __be16 port, int iif); 463 int (*to_addr_param) (const union sctp_addr *, 464 union sctp_addr_param *); 465 int (*addr_valid) (union sctp_addr *, 466 struct sctp_sock *, 467 const struct sk_buff *); 468 enum sctp_scope (*scope)(union sctp_addr *); 469 void (*inaddr_any) (union sctp_addr *, __be16); 470 int (*is_any) (const union sctp_addr *); 471 int (*available) (union sctp_addr *, 472 struct sctp_sock *); 473 int (*skb_iif) (const struct sk_buff *sk); 474 int (*skb_sdif)(const struct sk_buff *sk); 475 int (*is_ce) (const struct sk_buff *sk); 476 void (*seq_dump_addr)(struct seq_file *seq, 477 union sctp_addr *addr); 478 void (*ecn_capable)(struct sock *sk); 479 __u16 net_header_len; 480 int sockaddr_len; 481 int (*ip_options_len)(struct sock *sk); 482 sa_family_t sa_family; 483 struct list_head list; 484 }; 485 486 struct sctp_af *sctp_get_af_specific(sa_family_t); 487 int sctp_register_af(struct sctp_af *); 488 489 /* Protocol family functions. */ 490 struct sctp_pf { 491 void (*event_msgname)(struct sctp_ulpevent *, char *, int *); 492 void (*skb_msgname) (struct sk_buff *, char *, int *); 493 int (*af_supported) (sa_family_t, struct sctp_sock *); 494 int (*cmp_addr) (const union sctp_addr *, 495 const union sctp_addr *, 496 struct sctp_sock *); 497 int (*bind_verify) (struct sctp_sock *, union sctp_addr *); 498 int (*send_verify) (struct sctp_sock *, union sctp_addr *); 499 int (*supported_addrs)(const struct sctp_sock *, __be16 *); 500 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr); 501 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk); 502 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk); 503 void (*copy_ip_options)(struct sock *sk, struct sock *newsk); 504 struct sctp_af *af; 505 }; 506 507 508 /* Structure to track chunk fragments that have been acked, but peer 509 * fragments of the same message have not. 510 */ 511 struct sctp_datamsg { 512 /* Chunks waiting to be submitted to lower layer. */ 513 struct list_head chunks; 514 /* Reference counting. */ 515 refcount_t refcnt; 516 /* When is this message no longer interesting to the peer? */ 517 unsigned long expires_at; 518 /* Did the message fail to send? */ 519 int send_error; 520 u8 send_failed:1, 521 can_delay:1, /* should this message be Nagle delayed */ 522 abandoned:1; /* should this message be abandoned */ 523 }; 524 525 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *, 526 struct sctp_sndrcvinfo *, 527 struct iov_iter *); 528 void sctp_datamsg_free(struct sctp_datamsg *); 529 void sctp_datamsg_put(struct sctp_datamsg *); 530 void sctp_chunk_fail(struct sctp_chunk *, int error); 531 int sctp_chunk_abandoned(struct sctp_chunk *); 532 533 /* RFC2960 1.4 Key Terms 534 * 535 * o Chunk: A unit of information within an SCTP packet, consisting of 536 * a chunk header and chunk-specific content. 537 * 538 * As a matter of convenience, we remember the SCTP common header for 539 * each chunk as well as a few other header pointers... 540 */ 541 struct sctp_chunk { 542 struct list_head list; 543 544 refcount_t refcnt; 545 546 /* How many times this chunk have been sent, for prsctp RTX policy */ 547 int sent_count; 548 549 union { 550 /* This is our link to the per-transport transmitted list. */ 551 struct list_head transmitted_list; 552 /* List in specific stream outq */ 553 struct list_head stream_list; 554 }; 555 556 /* This field is used by chunks that hold fragmented data. 557 * For the first fragment this is the list that holds the rest of 558 * fragments. For the remaining fragments, this is the link to the 559 * frag_list maintained in the first fragment. 560 */ 561 struct list_head frag_list; 562 563 /* This points to the sk_buff containing the actual data. */ 564 struct sk_buff *skb; 565 566 union { 567 /* In case of GSO packets, this will store the head one */ 568 struct sk_buff *head_skb; 569 /* In case of auth enabled, this will point to the shkey */ 570 struct sctp_shared_key *shkey; 571 }; 572 573 /* These are the SCTP headers by reverse order in a packet. 574 * Note that some of these may happen more than once. In that 575 * case, we point at the "current" one, whatever that means 576 * for that level of header. 577 */ 578 579 /* We point this at the FIRST TLV parameter to chunk_hdr. */ 580 union sctp_params param_hdr; 581 union { 582 __u8 *v; 583 struct sctp_datahdr *data_hdr; 584 struct sctp_inithdr *init_hdr; 585 struct sctp_sackhdr *sack_hdr; 586 struct sctp_heartbeathdr *hb_hdr; 587 struct sctp_sender_hb_info *hbs_hdr; 588 struct sctp_shutdownhdr *shutdown_hdr; 589 struct sctp_signed_cookie *cookie_hdr; 590 struct sctp_ecnehdr *ecne_hdr; 591 struct sctp_cwrhdr *ecn_cwr_hdr; 592 struct sctp_errhdr *err_hdr; 593 struct sctp_addiphdr *addip_hdr; 594 struct sctp_fwdtsn_hdr *fwdtsn_hdr; 595 struct sctp_authhdr *auth_hdr; 596 struct sctp_idatahdr *idata_hdr; 597 struct sctp_ifwdtsn_hdr *ifwdtsn_hdr; 598 } subh; 599 600 __u8 *chunk_end; 601 602 struct sctp_chunkhdr *chunk_hdr; 603 struct sctphdr *sctp_hdr; 604 605 /* This needs to be recoverable for SCTP_SEND_FAILED events. */ 606 struct sctp_sndrcvinfo sinfo; 607 608 /* Which association does this belong to? */ 609 struct sctp_association *asoc; 610 611 /* What endpoint received this chunk? */ 612 struct sctp_ep_common *rcvr; 613 614 /* We fill this in if we are calculating RTT. */ 615 unsigned long sent_at; 616 617 /* What is the origin IP address for this chunk? */ 618 union sctp_addr source; 619 /* Destination address for this chunk. */ 620 union sctp_addr dest; 621 622 /* For outbound message, track all fragments for SEND_FAILED. */ 623 struct sctp_datamsg *msg; 624 625 /* For an inbound chunk, this tells us where it came from. 626 * For an outbound chunk, it tells us where we'd like it to 627 * go. It is NULL if we have no preference. 628 */ 629 struct sctp_transport *transport; 630 631 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO 632 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH 633 * spec violates the principle premis that all chunks are processed 634 * in order. 635 */ 636 struct sk_buff *auth_chunk; 637 638 #define SCTP_CAN_FRTX 0x0 639 #define SCTP_NEED_FRTX 0x1 640 #define SCTP_DONT_FRTX 0x2 641 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */ 642 has_tsn:1, /* Does this chunk have a TSN yet? */ 643 has_ssn:1, /* Does this chunk have a SSN yet? */ 644 #define has_mid has_ssn 645 singleton:1, /* Only chunk in the packet? */ 646 end_of_packet:1, /* Last chunk in the packet? */ 647 ecn_ce_done:1, /* Have we processed the ECN CE bit? */ 648 pdiscard:1, /* Discard the whole packet now? */ 649 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */ 650 data_accepted:1, /* At least 1 chunk accepted */ 651 auth:1, /* IN: was auth'ed | OUT: needs auth */ 652 has_asconf:1, /* IN: have seen an asconf before */ 653 pmtu_probe:1, /* Used by PLPMTUD, can be set in s HB chunk */ 654 tsn_missing_report:2, /* Data chunk missing counter. */ 655 fast_retransmit:2; /* Is this chunk fast retransmitted? */ 656 }; 657 658 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1) 659 void sctp_chunk_hold(struct sctp_chunk *); 660 void sctp_chunk_put(struct sctp_chunk *); 661 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len, 662 struct iov_iter *from); 663 void sctp_chunk_free(struct sctp_chunk *); 664 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data); 665 struct sctp_chunk *sctp_chunkify(struct sk_buff *, 666 const struct sctp_association *, 667 struct sock *, gfp_t gfp); 668 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *, 669 union sctp_addr *); 670 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk); 671 672 static inline __u16 sctp_chunk_stream_no(struct sctp_chunk *ch) 673 { 674 return ntohs(ch->subh.data_hdr->stream); 675 } 676 677 enum { 678 SCTP_ADDR_NEW, /* new address added to assoc/ep */ 679 SCTP_ADDR_SRC, /* address can be used as source */ 680 SCTP_ADDR_DEL, /* address about to be deleted */ 681 }; 682 683 /* This is a structure for holding either an IPv6 or an IPv4 address. */ 684 struct sctp_sockaddr_entry { 685 struct list_head list; 686 struct rcu_head rcu; 687 union sctp_addr a; 688 __u8 state; 689 __u8 valid; 690 }; 691 692 #define SCTP_ADDRESS_TICK_DELAY 500 693 694 /* This structure holds lists of chunks as we are assembling for 695 * transmission. 696 */ 697 struct sctp_packet { 698 /* These are the SCTP header values (host order) for the packet. */ 699 __u16 source_port; 700 __u16 destination_port; 701 __u32 vtag; 702 703 /* This contains the payload chunks. */ 704 struct list_head chunk_list; 705 706 /* This is the overhead of the sctp and ip headers. */ 707 size_t overhead; 708 /* This is the total size of all chunks INCLUDING padding. */ 709 size_t size; 710 /* This is the maximum size this packet may have */ 711 size_t max_size; 712 713 /* The packet is destined for this transport address. 714 * The function we finally use to pass down to the next lower 715 * layer lives in the transport structure. 716 */ 717 struct sctp_transport *transport; 718 719 /* pointer to the auth chunk for this packet */ 720 struct sctp_chunk *auth; 721 722 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */ 723 has_sack:1, /* This packet contains a SACK chunk. */ 724 has_auth:1, /* This packet contains an AUTH chunk */ 725 has_data:1, /* This packet contains at least 1 DATA chunk */ 726 ipfragok:1; /* So let ip fragment this packet */ 727 }; 728 729 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *, 730 __u16 sport, __u16 dport); 731 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int); 732 enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet, 733 struct sctp_chunk *chunk, 734 int one_packet, gfp_t gfp); 735 enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet, 736 struct sctp_chunk *chunk); 737 int sctp_packet_transmit(struct sctp_packet *, gfp_t); 738 void sctp_packet_free(struct sctp_packet *); 739 740 static inline int sctp_packet_empty(struct sctp_packet *packet) 741 { 742 return packet->size == packet->overhead; 743 } 744 745 /* This represents a remote transport address. 746 * For local transport addresses, we just use union sctp_addr. 747 * 748 * RFC2960 Section 1.4 Key Terms 749 * 750 * o Transport address: A Transport Address is traditionally defined 751 * by Network Layer address, Transport Layer protocol and Transport 752 * Layer port number. In the case of SCTP running over IP, a 753 * transport address is defined by the combination of an IP address 754 * and an SCTP port number (where SCTP is the Transport protocol). 755 * 756 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control 757 * 758 * o The sender keeps a separate congestion control parameter set for 759 * each of the destination addresses it can send to (not each 760 * source-destination pair but for each destination). The parameters 761 * should decay if the address is not used for a long enough time 762 * period. 763 * 764 */ 765 struct sctp_transport { 766 /* A list of transports. */ 767 struct list_head transports; 768 struct rhlist_head node; 769 770 /* Reference counting. */ 771 refcount_t refcnt; 772 __u32 dead:1, 773 /* RTO-Pending : A flag used to track if one of the DATA 774 * chunks sent to this address is currently being 775 * used to compute a RTT. If this flag is 0, 776 * the next DATA chunk sent to this destination 777 * should be used to compute a RTT and this flag 778 * should be set. Every time the RTT 779 * calculation completes (i.e. the DATA chunk 780 * is SACK'd) clear this flag. 781 */ 782 rto_pending:1, 783 784 /* 785 * hb_sent : a flag that signals that we have a pending 786 * heartbeat. 787 */ 788 hb_sent:1, 789 790 /* Is the Path MTU update pending on this transport */ 791 pmtu_pending:1, 792 793 dst_pending_confirm:1, /* need to confirm neighbour */ 794 795 /* Has this transport moved the ctsn since we last sacked */ 796 sack_generation:1; 797 u32 dst_cookie; 798 799 struct flowi fl; 800 801 /* This is the peer's IP address and port. */ 802 union sctp_addr ipaddr; 803 804 /* These are the functions we call to handle LLP stuff. */ 805 struct sctp_af *af_specific; 806 807 /* Which association do we belong to? */ 808 struct sctp_association *asoc; 809 810 /* RFC2960 811 * 812 * 12.3 Per Transport Address Data 813 * 814 * For each destination transport address in the peer's 815 * address list derived from the INIT or INIT ACK chunk, a 816 * number of data elements needs to be maintained including: 817 */ 818 /* RTO : The current retransmission timeout value. */ 819 unsigned long rto; 820 821 __u32 rtt; /* This is the most recent RTT. */ 822 823 /* RTTVAR : The current RTT variation. */ 824 __u32 rttvar; 825 826 /* SRTT : The current smoothed round trip time. */ 827 __u32 srtt; 828 829 /* 830 * These are the congestion stats. 831 */ 832 /* cwnd : The current congestion window. */ 833 __u32 cwnd; /* This is the actual cwnd. */ 834 835 /* ssthresh : The current slow start threshold value. */ 836 __u32 ssthresh; 837 838 /* partial : The tracking method for increase of cwnd when in 839 * bytes acked : congestion avoidance mode (see Section 6.2.2) 840 */ 841 __u32 partial_bytes_acked; 842 843 /* Data that has been sent, but not acknowledged. */ 844 __u32 flight_size; 845 846 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */ 847 848 /* Destination */ 849 struct dst_entry *dst; 850 /* Source address. */ 851 union sctp_addr saddr; 852 853 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 854 * the destination address every heartbeat interval. 855 */ 856 unsigned long hbinterval; 857 unsigned long probe_interval; 858 859 /* SACK delay timeout */ 860 unsigned long sackdelay; 861 __u32 sackfreq; 862 863 atomic_t mtu_info; 864 865 /* When was the last time that we heard from this transport? We use 866 * this to pick new active and retran paths. 867 */ 868 ktime_t last_time_heard; 869 870 /* When was the last time that we sent a chunk using this 871 * transport? We use this to check for idle transports 872 */ 873 unsigned long last_time_sent; 874 875 /* Last time(in jiffies) when cwnd is reduced due to the congestion 876 * indication based on ECNE chunk. 877 */ 878 unsigned long last_time_ecne_reduced; 879 880 __be16 encap_port; 881 882 /* This is the max_retrans value for the transport and will 883 * be initialized from the assocs value. This can be changed 884 * using the SCTP_SET_PEER_ADDR_PARAMS socket option. 885 */ 886 __u16 pathmaxrxt; 887 888 __u32 flowlabel; 889 __u8 dscp; 890 891 /* This is the partially failed retrans value for the transport 892 * and will be initialized from the assocs value. This can be changed 893 * using the SCTP_PEER_ADDR_THLDS socket option 894 */ 895 __u16 pf_retrans; 896 /* Used for primary path switchover. */ 897 __u16 ps_retrans; 898 /* PMTU : The current known path MTU. */ 899 __u32 pathmtu; 900 901 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 902 __u32 param_flags; 903 904 /* The number of times INIT has been sent on this transport. */ 905 int init_sent_count; 906 907 /* state : The current state of this destination, 908 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN. 909 */ 910 int state; 911 912 /* These are the error stats for this destination. */ 913 914 /* Error count : The current error count for this destination. */ 915 unsigned short error_count; 916 917 /* Per : A timer used by each destination. 918 * Destination : 919 * Timer : 920 * 921 * [Everywhere else in the text this is called T3-rtx. -ed] 922 */ 923 struct timer_list T3_rtx_timer; 924 925 /* Heartbeat timer is per destination. */ 926 struct timer_list hb_timer; 927 928 /* Timer to handle ICMP proto unreachable envets */ 929 struct timer_list proto_unreach_timer; 930 931 /* Timer to handler reconf chunk rtx */ 932 struct timer_list reconf_timer; 933 934 /* Timer to send a probe HB packet for PLPMTUD */ 935 struct timer_list probe_timer; 936 937 /* Since we're using per-destination retransmission timers 938 * (see above), we're also using per-destination "transmitted" 939 * queues. This probably ought to be a private struct 940 * accessible only within the outqueue, but it's not, yet. 941 */ 942 struct list_head transmitted; 943 944 /* We build bundle-able packets for this transport here. */ 945 struct sctp_packet packet; 946 947 /* This is the list of transports that have chunks to send. */ 948 struct list_head send_ready; 949 950 /* State information saved for SFR_CACC algorithm. The key 951 * idea in SFR_CACC is to maintain state at the sender on a 952 * per-destination basis when a changeover happens. 953 * char changeover_active; 954 * char cycling_changeover; 955 * __u32 next_tsn_at_change; 956 * char cacc_saw_newack; 957 */ 958 struct { 959 /* An unsigned integer, which stores the next TSN to be 960 * used by the sender, at the moment of changeover. 961 */ 962 __u32 next_tsn_at_change; 963 964 /* A flag which indicates the occurrence of a changeover */ 965 char changeover_active; 966 967 /* A flag which indicates whether the change of primary is 968 * the first switch to this destination address during an 969 * active switch. 970 */ 971 char cycling_changeover; 972 973 /* A temporary flag, which is used during the processing of 974 * a SACK to estimate the causative TSN(s)'s group. 975 */ 976 char cacc_saw_newack; 977 } cacc; 978 979 struct { 980 __u16 pmtu; 981 __u16 probe_size; 982 __u16 probe_high; 983 __u8 probe_count; 984 __u8 state; 985 } pl; /* plpmtud related */ 986 987 /* 64-bit random number sent with heartbeat. */ 988 __u64 hb_nonce; 989 990 struct rcu_head rcu; 991 }; 992 993 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *, 994 gfp_t); 995 void sctp_transport_set_owner(struct sctp_transport *, 996 struct sctp_association *); 997 void sctp_transport_route(struct sctp_transport *, union sctp_addr *, 998 struct sctp_sock *); 999 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk); 1000 void sctp_transport_free(struct sctp_transport *); 1001 void sctp_transport_reset_t3_rtx(struct sctp_transport *); 1002 void sctp_transport_reset_hb_timer(struct sctp_transport *); 1003 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport); 1004 void sctp_transport_reset_probe_timer(struct sctp_transport *transport); 1005 void sctp_transport_reset_raise_timer(struct sctp_transport *transport); 1006 int sctp_transport_hold(struct sctp_transport *); 1007 void sctp_transport_put(struct sctp_transport *); 1008 void sctp_transport_update_rto(struct sctp_transport *, __u32); 1009 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32); 1010 void sctp_transport_lower_cwnd(struct sctp_transport *t, 1011 enum sctp_lower_cwnd reason); 1012 void sctp_transport_burst_limited(struct sctp_transport *); 1013 void sctp_transport_burst_reset(struct sctp_transport *); 1014 unsigned long sctp_transport_timeout(struct sctp_transport *); 1015 void sctp_transport_reset(struct sctp_transport *t); 1016 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu); 1017 void sctp_transport_immediate_rtx(struct sctp_transport *); 1018 void sctp_transport_dst_release(struct sctp_transport *t); 1019 void sctp_transport_dst_confirm(struct sctp_transport *t); 1020 void sctp_transport_pl_send(struct sctp_transport *t); 1021 bool sctp_transport_pl_recv(struct sctp_transport *t); 1022 1023 1024 /* This is the structure we use to queue packets as they come into 1025 * SCTP. We write packets to it and read chunks from it. 1026 */ 1027 struct sctp_inq { 1028 /* This is actually a queue of sctp_chunk each 1029 * containing a partially decoded packet. 1030 */ 1031 struct list_head in_chunk_list; 1032 /* This is the packet which is currently off the in queue and is 1033 * being worked on through the inbound chunk processing. 1034 */ 1035 struct sctp_chunk *in_progress; 1036 1037 /* This is the delayed task to finish delivering inbound 1038 * messages. 1039 */ 1040 struct work_struct immediate; 1041 }; 1042 1043 void sctp_inq_init(struct sctp_inq *); 1044 void sctp_inq_free(struct sctp_inq *); 1045 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet); 1046 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *); 1047 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *); 1048 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t); 1049 1050 /* This is the structure we use to hold outbound chunks. You push 1051 * chunks in and they automatically pop out the other end as bundled 1052 * packets (it calls (*output_handler)()). 1053 * 1054 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1, 1055 * and 8.2 of the v13 draft. 1056 * 1057 * It handles retransmissions. The connection to the timeout portion 1058 * of the state machine is through sctp_..._timeout() and timeout_handler. 1059 * 1060 * If you feed it SACKs, it will eat them. 1061 * 1062 * If you give it big chunks, it will fragment them. 1063 * 1064 * It assigns TSN's to data chunks. This happens at the last possible 1065 * instant before transmission. 1066 * 1067 * When free()'d, it empties itself out via output_handler(). 1068 */ 1069 struct sctp_outq { 1070 struct sctp_association *asoc; 1071 1072 /* Data pending that has never been transmitted. */ 1073 struct list_head out_chunk_list; 1074 1075 /* Stream scheduler being used */ 1076 const struct sctp_sched_ops *sched; 1077 1078 unsigned int out_qlen; /* Total length of queued data chunks. */ 1079 1080 /* Error of send failed, may used in SCTP_SEND_FAILED event. */ 1081 unsigned int error; 1082 1083 /* These are control chunks we want to send. */ 1084 struct list_head control_chunk_list; 1085 1086 /* These are chunks that have been sacked but are above the 1087 * CTSN, or cumulative tsn ack point. 1088 */ 1089 struct list_head sacked; 1090 1091 /* Put chunks on this list to schedule them for 1092 * retransmission. 1093 */ 1094 struct list_head retransmit; 1095 1096 /* Put chunks on this list to save them for FWD TSN processing as 1097 * they were abandoned. 1098 */ 1099 struct list_head abandoned; 1100 1101 /* How many unackd bytes do we have in-flight? */ 1102 __u32 outstanding_bytes; 1103 1104 /* Are we doing fast-rtx on this queue */ 1105 char fast_rtx; 1106 1107 /* Corked? */ 1108 char cork; 1109 }; 1110 1111 void sctp_outq_init(struct sctp_association *, struct sctp_outq *); 1112 void sctp_outq_teardown(struct sctp_outq *); 1113 void sctp_outq_free(struct sctp_outq*); 1114 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t); 1115 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *); 1116 int sctp_outq_is_empty(const struct sctp_outq *); 1117 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport, 1118 enum sctp_retransmit_reason reason); 1119 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8); 1120 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp); 1121 void sctp_prsctp_prune(struct sctp_association *asoc, 1122 struct sctp_sndrcvinfo *sinfo, int msg_len); 1123 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn); 1124 /* Uncork and flush an outqueue. */ 1125 static inline void sctp_outq_cork(struct sctp_outq *q) 1126 { 1127 q->cork = 1; 1128 } 1129 1130 /* SCTP skb control block. 1131 * sctp_input_cb is currently used on rx and sock rx queue 1132 */ 1133 struct sctp_input_cb { 1134 union { 1135 struct inet_skb_parm h4; 1136 #if IS_ENABLED(CONFIG_IPV6) 1137 struct inet6_skb_parm h6; 1138 #endif 1139 } header; 1140 struct sctp_chunk *chunk; 1141 struct sctp_af *af; 1142 __be16 encap_port; 1143 }; 1144 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0])) 1145 1146 struct sctp_output_cb { 1147 struct sk_buff *last; 1148 }; 1149 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0])) 1150 1151 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb) 1152 { 1153 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; 1154 1155 return chunk->head_skb ? : skb; 1156 } 1157 1158 /* These bind address data fields common between endpoints and associations */ 1159 struct sctp_bind_addr { 1160 1161 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1162 * 1163 * SCTP Port: The local SCTP port number the endpoint is 1164 * bound to. 1165 */ 1166 __u16 port; 1167 1168 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1169 * 1170 * Address List: The list of IP addresses that this instance 1171 * has bound. This information is passed to one's 1172 * peer(s) in INIT and INIT ACK chunks. 1173 */ 1174 struct list_head address_list; 1175 }; 1176 1177 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port); 1178 void sctp_bind_addr_free(struct sctp_bind_addr *); 1179 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest, 1180 const struct sctp_bind_addr *src, 1181 enum sctp_scope scope, gfp_t gfp, 1182 int flags); 1183 int sctp_bind_addr_dup(struct sctp_bind_addr *dest, 1184 const struct sctp_bind_addr *src, 1185 gfp_t gfp); 1186 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *, 1187 int new_size, __u8 addr_state, gfp_t gfp); 1188 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *); 1189 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *, 1190 struct sctp_sock *); 1191 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *, 1192 struct sctp_sock *, struct sctp_sock *); 1193 int sctp_bind_addr_state(const struct sctp_bind_addr *bp, 1194 const union sctp_addr *addr); 1195 int sctp_bind_addrs_check(struct sctp_sock *sp, 1196 struct sctp_sock *sp2, int cnt2); 1197 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp, 1198 const union sctp_addr *addrs, 1199 int addrcnt, 1200 struct sctp_sock *opt); 1201 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp, 1202 int *addrs_len, 1203 gfp_t gfp); 1204 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len, 1205 __u16 port, gfp_t gfp); 1206 1207 enum sctp_scope sctp_scope(const union sctp_addr *addr); 1208 int sctp_in_scope(struct net *net, const union sctp_addr *addr, 1209 const enum sctp_scope scope); 1210 int sctp_is_any(struct sock *sk, const union sctp_addr *addr); 1211 int sctp_is_ep_boundall(struct sock *sk); 1212 1213 1214 /* What type of endpoint? */ 1215 enum sctp_endpoint_type { 1216 SCTP_EP_TYPE_SOCKET, 1217 SCTP_EP_TYPE_ASSOCIATION, 1218 }; 1219 1220 /* 1221 * A common base class to bridge the implementation view of a 1222 * socket (usually listening) endpoint versus an association's 1223 * local endpoint. 1224 * This common structure is useful for several purposes: 1225 * 1) Common interface for lookup routines. 1226 * a) Subfunctions work for either endpoint or association 1227 * b) Single interface to lookup allows hiding the lookup lock rather 1228 * than acquiring it externally. 1229 * 2) Common interface for the inbound chunk handling/state machine. 1230 * 3) Common object handling routines for reference counting, etc. 1231 * 4) Disentangle association lookup from endpoint lookup, where we 1232 * do not have to find our endpoint to find our association. 1233 * 1234 */ 1235 1236 struct sctp_ep_common { 1237 /* Runtime type information. What kind of endpoint is this? */ 1238 enum sctp_endpoint_type type; 1239 1240 /* Some fields to help us manage this object. 1241 * refcnt - Reference count access to this object. 1242 * dead - Do not attempt to use this object. 1243 */ 1244 refcount_t refcnt; 1245 bool dead; 1246 1247 /* What socket does this endpoint belong to? */ 1248 struct sock *sk; 1249 1250 /* Cache netns and it won't change once set */ 1251 struct net *net; 1252 1253 /* This is where we receive inbound chunks. */ 1254 struct sctp_inq inqueue; 1255 1256 /* This substructure includes the defining parameters of the 1257 * endpoint: 1258 * bind_addr.port is our shared port number. 1259 * bind_addr.address_list is our set of local IP addresses. 1260 */ 1261 struct sctp_bind_addr bind_addr; 1262 }; 1263 1264 1265 /* RFC Section 1.4 Key Terms 1266 * 1267 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a 1268 * multi-homed host, an SCTP endpoint is represented to its peers as a 1269 * combination of a set of eligible destination transport addresses to 1270 * which SCTP packets can be sent and a set of eligible source 1271 * transport addresses from which SCTP packets can be received. 1272 * All transport addresses used by an SCTP endpoint must use the 1273 * same port number, but can use multiple IP addresses. A transport 1274 * address used by an SCTP endpoint must not be used by another 1275 * SCTP endpoint. In other words, a transport address is unique 1276 * to an SCTP endpoint. 1277 * 1278 * From an implementation perspective, each socket has one of these. 1279 * A TCP-style socket will have exactly one association on one of 1280 * these. An UDP-style socket will have multiple associations hanging 1281 * off one of these. 1282 */ 1283 1284 struct sctp_endpoint { 1285 /* Common substructure for endpoint and association. */ 1286 struct sctp_ep_common base; 1287 1288 /* Fields to help us manage our entries in the hash tables. */ 1289 struct hlist_node node; 1290 int hashent; 1291 1292 /* Associations: A list of current associations and mappings 1293 * to the data consumers for each association. This 1294 * may be in the form of a hash table or other 1295 * implementation dependent structure. The data 1296 * consumers may be process identification 1297 * information such as file descriptors, named pipe 1298 * pointer, or table pointers dependent on how SCTP 1299 * is implemented. 1300 */ 1301 /* This is really a list of struct sctp_association entries. */ 1302 struct list_head asocs; 1303 1304 /* Cookie authentication key used by this endpoint */ 1305 struct hmac_sha256_key cookie_auth_key; 1306 1307 /* sendbuf acct. policy. */ 1308 __u32 sndbuf_policy; 1309 1310 /* rcvbuf acct. policy. */ 1311 __u32 rcvbuf_policy; 1312 1313 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */ 1314 struct sctp_hmac_algo_param *auth_hmacs_list; 1315 1316 /* SCTP-AUTH: chunks to authenticate encoded into parameter */ 1317 struct sctp_chunks_param *auth_chunk_list; 1318 1319 /* SCTP-AUTH: endpoint shared keys */ 1320 struct list_head endpoint_shared_keys; 1321 __u16 active_key_id; 1322 __u8 ecn_enable:1, 1323 auth_enable:1, 1324 intl_enable:1, 1325 prsctp_enable:1, 1326 asconf_enable:1, 1327 reconf_enable:1; 1328 1329 __u8 strreset_enable; 1330 struct rcu_head rcu; 1331 }; 1332 1333 /* Recover the outer endpoint structure. */ 1334 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base) 1335 { 1336 struct sctp_endpoint *ep; 1337 1338 ep = container_of(base, struct sctp_endpoint, base); 1339 return ep; 1340 } 1341 1342 /* These are function signatures for manipulating endpoints. */ 1343 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t); 1344 void sctp_endpoint_free(struct sctp_endpoint *); 1345 void sctp_endpoint_put(struct sctp_endpoint *); 1346 int sctp_endpoint_hold(struct sctp_endpoint *ep); 1347 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *); 1348 struct sctp_association *sctp_endpoint_lookup_assoc( 1349 const struct sctp_endpoint *ep, 1350 const union sctp_addr *paddr, 1351 struct sctp_transport **); 1352 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep, 1353 const union sctp_addr *paddr); 1354 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *ep, 1355 struct net *net, 1356 const union sctp_addr *laddr, 1357 int dif, int sdif); 1358 bool sctp_has_association(struct net *net, const union sctp_addr *laddr, 1359 const union sctp_addr *paddr, int dif, int sdif); 1360 1361 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep, 1362 const struct sctp_association *asoc, 1363 enum sctp_cid cid, struct sctp_init_chunk *peer_init, 1364 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk); 1365 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk, 1366 const union sctp_addr *peer, 1367 struct sctp_init_chunk *init, gfp_t gfp); 1368 __u32 sctp_generate_tag(const struct sctp_endpoint *); 1369 __u32 sctp_generate_tsn(const struct sctp_endpoint *); 1370 1371 struct sctp_inithdr_host { 1372 __u32 init_tag; 1373 __u32 a_rwnd; 1374 __u16 num_outbound_streams; 1375 __u16 num_inbound_streams; 1376 __u32 initial_tsn; 1377 }; 1378 1379 struct sctp_stream_priorities { 1380 /* List of priorities scheduled */ 1381 struct list_head prio_sched; 1382 /* List of streams scheduled */ 1383 struct list_head active; 1384 /* The next stream in line */ 1385 struct sctp_stream_out_ext *next; 1386 __u16 prio; 1387 __u16 users; 1388 }; 1389 1390 struct sctp_stream_out_ext { 1391 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 1392 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 1393 struct list_head outq; /* chunks enqueued by this stream */ 1394 union { 1395 struct { 1396 /* Scheduled streams list */ 1397 struct list_head prio_list; 1398 struct sctp_stream_priorities *prio_head; 1399 }; 1400 /* Fields used by RR scheduler */ 1401 struct { 1402 struct list_head rr_list; 1403 }; 1404 struct { 1405 struct list_head fc_list; 1406 __u32 fc_length; 1407 __u16 fc_weight; 1408 }; 1409 }; 1410 }; 1411 1412 struct sctp_stream_out { 1413 union { 1414 __u32 mid; 1415 __u16 ssn; 1416 }; 1417 __u32 mid_uo; 1418 struct sctp_stream_out_ext *ext; 1419 __u8 state; 1420 }; 1421 1422 struct sctp_stream_in { 1423 union { 1424 __u32 mid; 1425 __u16 ssn; 1426 }; 1427 __u32 mid_uo; 1428 __u32 fsn; 1429 __u32 fsn_uo; 1430 char pd_mode; 1431 char pd_mode_uo; 1432 }; 1433 1434 struct sctp_stream { 1435 GENRADIX(struct sctp_stream_out) out; 1436 GENRADIX(struct sctp_stream_in) in; 1437 1438 __u16 outcnt; 1439 __u16 incnt; 1440 /* Current stream being sent, if any */ 1441 struct sctp_stream_out *out_curr; 1442 union { 1443 /* Fields used by priority scheduler */ 1444 struct { 1445 /* List of priorities scheduled */ 1446 struct list_head prio_list; 1447 }; 1448 /* Fields used by RR scheduler */ 1449 struct { 1450 /* List of streams scheduled */ 1451 struct list_head rr_list; 1452 /* The next stream in line */ 1453 struct sctp_stream_out_ext *rr_next; 1454 }; 1455 struct { 1456 struct list_head fc_list; 1457 }; 1458 }; 1459 struct sctp_stream_interleave *si; 1460 }; 1461 1462 static inline struct sctp_stream_out *sctp_stream_out( 1463 struct sctp_stream *stream, 1464 __u16 sid) 1465 { 1466 return genradix_ptr(&stream->out, sid); 1467 } 1468 1469 static inline struct sctp_stream_in *sctp_stream_in( 1470 struct sctp_stream *stream, 1471 __u16 sid) 1472 { 1473 return genradix_ptr(&stream->in, sid); 1474 } 1475 1476 #define SCTP_SO(s, i) sctp_stream_out((s), (i)) 1477 #define SCTP_SI(s, i) sctp_stream_in((s), (i)) 1478 1479 #define SCTP_STREAM_CLOSED 0x00 1480 #define SCTP_STREAM_OPEN 0x01 1481 1482 static inline __u16 sctp_datachk_len(const struct sctp_stream *stream) 1483 { 1484 return stream->si->data_chunk_len; 1485 } 1486 1487 static inline __u16 sctp_datahdr_len(const struct sctp_stream *stream) 1488 { 1489 return stream->si->data_chunk_len - sizeof(struct sctp_chunkhdr); 1490 } 1491 1492 static inline __u16 sctp_ftsnchk_len(const struct sctp_stream *stream) 1493 { 1494 return stream->si->ftsn_chunk_len; 1495 } 1496 1497 static inline __u16 sctp_ftsnhdr_len(const struct sctp_stream *stream) 1498 { 1499 return stream->si->ftsn_chunk_len - sizeof(struct sctp_chunkhdr); 1500 } 1501 1502 /* SCTP_GET_ASSOC_STATS counters */ 1503 struct sctp_priv_assoc_stats { 1504 /* Maximum observed rto in the association during subsequent 1505 * observations. Value is set to 0 if no RTO measurement took place 1506 * The transport where the max_rto was observed is returned in 1507 * obs_rto_ipaddr 1508 */ 1509 struct sockaddr_storage obs_rto_ipaddr; 1510 __u64 max_obs_rto; 1511 /* Total In and Out SACKs received and sent */ 1512 __u64 isacks; 1513 __u64 osacks; 1514 /* Total In and Out packets received and sent */ 1515 __u64 opackets; 1516 __u64 ipackets; 1517 /* Total retransmitted chunks */ 1518 __u64 rtxchunks; 1519 /* TSN received > next expected */ 1520 __u64 outofseqtsns; 1521 /* Duplicate Chunks received */ 1522 __u64 idupchunks; 1523 /* Gap Ack Blocks received */ 1524 __u64 gapcnt; 1525 /* Unordered data chunks sent and received */ 1526 __u64 ouodchunks; 1527 __u64 iuodchunks; 1528 /* Ordered data chunks sent and received */ 1529 __u64 oodchunks; 1530 __u64 iodchunks; 1531 /* Control chunks sent and received */ 1532 __u64 octrlchunks; 1533 __u64 ictrlchunks; 1534 }; 1535 1536 /* RFC2960 1537 * 1538 * 12. Recommended Transmission Control Block (TCB) Parameters 1539 * 1540 * This section details a recommended set of parameters that should 1541 * be contained within the TCB for an implementation. This section is 1542 * for illustrative purposes and should not be deemed as requirements 1543 * on an implementation or as an exhaustive list of all parameters 1544 * inside an SCTP TCB. Each implementation may need its own additional 1545 * parameters for optimization. 1546 */ 1547 1548 1549 /* Here we have information about each individual association. */ 1550 struct sctp_association { 1551 1552 /* A base structure common to endpoint and association. 1553 * In this context, it represents the associations's view 1554 * of the local endpoint of the association. 1555 */ 1556 struct sctp_ep_common base; 1557 1558 /* Associations on the same socket. */ 1559 struct list_head asocs; 1560 1561 /* association id. */ 1562 sctp_assoc_t assoc_id; 1563 1564 /* This is our parent endpoint. */ 1565 struct sctp_endpoint *ep; 1566 1567 /* These are those association elements needed in the cookie. */ 1568 struct sctp_cookie c; 1569 1570 /* This is all information about our peer. */ 1571 struct { 1572 /* transport_addr_list 1573 * 1574 * Peer : A list of SCTP transport addresses that the 1575 * Transport : peer is bound to. This information is derived 1576 * Address : from the INIT or INIT ACK and is used to 1577 * List : associate an inbound packet with a given 1578 * : association. Normally this information is 1579 * : hashed or keyed for quick lookup and access 1580 * : of the TCB. 1581 * : The list is also initialized with the list 1582 * : of addresses passed with the sctp_connectx() 1583 * : call. 1584 * 1585 * It is a list of SCTP_transport's. 1586 */ 1587 struct list_head transport_addr_list; 1588 1589 /* rwnd 1590 * 1591 * Peer Rwnd : Current calculated value of the peer's rwnd. 1592 */ 1593 __u32 rwnd; 1594 1595 /* transport_count 1596 * 1597 * Peer : A count of the number of peer addresses 1598 * Transport : in the Peer Transport Address List. 1599 * Address : 1600 * Count : 1601 */ 1602 __u16 transport_count; 1603 1604 /* port 1605 * The transport layer port number. 1606 */ 1607 __u16 port; 1608 1609 /* primary_path 1610 * 1611 * Primary : This is the current primary destination 1612 * Path : transport address of the peer endpoint. It 1613 * : may also specify a source transport address 1614 * : on this endpoint. 1615 * 1616 * All of these paths live on transport_addr_list. 1617 * 1618 * At the bakeoffs, we discovered that the intent of 1619 * primaryPath is that it only changes when the ULP 1620 * asks to have it changed. We add the activePath to 1621 * designate the connection we are currently using to 1622 * transmit new data and most control chunks. 1623 */ 1624 struct sctp_transport *primary_path; 1625 1626 /* Cache the primary path address here, when we 1627 * need a an address for msg_name. 1628 */ 1629 union sctp_addr primary_addr; 1630 1631 /* active_path 1632 * The path that we are currently using to 1633 * transmit new data and most control chunks. 1634 */ 1635 struct sctp_transport *active_path; 1636 1637 /* retran_path 1638 * 1639 * RFC2960 6.4 Multi-homed SCTP Endpoints 1640 * ... 1641 * Furthermore, when its peer is multi-homed, an 1642 * endpoint SHOULD try to retransmit a chunk to an 1643 * active destination transport address that is 1644 * different from the last destination address to 1645 * which the DATA chunk was sent. 1646 */ 1647 struct sctp_transport *retran_path; 1648 1649 /* Pointer to last transport I have sent on. */ 1650 struct sctp_transport *last_sent_to; 1651 1652 /* This is the last transport I have received DATA on. */ 1653 struct sctp_transport *last_data_from; 1654 1655 /* 1656 * Mapping An array of bits or bytes indicating which out of 1657 * Array order TSN's have been received (relative to the 1658 * Last Rcvd TSN). If no gaps exist, i.e. no out of 1659 * order packets have been received, this array 1660 * will be set to all zero. This structure may be 1661 * in the form of a circular buffer or bit array. 1662 * 1663 * Last Rcvd : This is the last TSN received in 1664 * TSN : sequence. This value is set initially by 1665 * : taking the peer's Initial TSN, received in 1666 * : the INIT or INIT ACK chunk, and subtracting 1667 * : one from it. 1668 * 1669 * Throughout most of the specification this is called the 1670 * "Cumulative TSN ACK Point". In this case, we 1671 * ignore the advice in 12.2 in favour of the term 1672 * used in the bulk of the text. This value is hidden 1673 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn(). 1674 */ 1675 struct sctp_tsnmap tsn_map; 1676 1677 /* This mask is used to disable sending the ASCONF chunk 1678 * with specified parameter to peer. 1679 */ 1680 __be16 addip_disabled_mask; 1681 1682 /* These are capabilities which our peer advertised. */ 1683 __u16 ecn_capable:1, /* Can peer do ECN? */ 1684 ipv4_address:1, /* Peer understands IPv4 addresses? */ 1685 ipv6_address:1, /* Peer understands IPv6 addresses? */ 1686 asconf_capable:1, /* Does peer support ADDIP? */ 1687 prsctp_capable:1, /* Can peer do PR-SCTP? */ 1688 reconf_capable:1, /* Can peer do RE-CONFIG? */ 1689 intl_capable:1, /* Can peer do INTERLEAVE */ 1690 auth_capable:1, /* Is peer doing SCTP-AUTH? */ 1691 /* sack_needed: 1692 * This flag indicates if the next received 1693 * packet is to be responded to with a 1694 * SACK. This is initialized to 0. When a packet 1695 * is received sack_cnt is incremented. If this value 1696 * reaches 2 or more, a SACK is sent and the 1697 * value is reset to 0. Note: This is used only 1698 * when no DATA chunks are received out of 1699 * order. When DATA chunks are out of order, 1700 * SACK's are not delayed (see Section 6). 1701 */ 1702 sack_needed:1, /* Do we need to sack the peer? */ 1703 sack_generation:1, 1704 zero_window_announced:1; 1705 1706 __u32 sack_cnt; 1707 1708 __u32 adaptation_ind; /* Adaptation Code point. */ 1709 1710 struct sctp_inithdr_host i; 1711 void *cookie; 1712 int cookie_len; 1713 1714 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. 1715 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the 1716 * Initial TSN Value minus 1 1717 */ 1718 __u32 addip_serial; 1719 1720 /* SCTP-AUTH: We need to know pears random number, hmac list 1721 * and authenticated chunk list. All that is part of the 1722 * cookie and these are just pointers to those locations 1723 */ 1724 struct sctp_random_param *peer_random; 1725 struct sctp_chunks_param *peer_chunks; 1726 struct sctp_hmac_algo_param *peer_hmacs; 1727 } peer; 1728 1729 /* State : A state variable indicating what state the 1730 * : association is in, i.e. COOKIE-WAIT, 1731 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING, 1732 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT. 1733 * 1734 * Note: No "CLOSED" state is illustrated since if a 1735 * association is "CLOSED" its TCB SHOULD be removed. 1736 * 1737 * In this implementation we DO have a CLOSED 1738 * state which is used during initiation and shutdown. 1739 * 1740 * State takes values from SCTP_STATE_*. 1741 */ 1742 enum sctp_state state; 1743 1744 /* Overall : The overall association error count. 1745 * Error Count : [Clear this any time I get something.] 1746 */ 1747 int overall_error_count; 1748 1749 /* The cookie life I award for any cookie. */ 1750 ktime_t cookie_life; 1751 1752 /* These are the association's initial, max, and min RTO values. 1753 * These values will be initialized by system defaults, but can 1754 * be modified via the SCTP_RTOINFO socket option. 1755 */ 1756 unsigned long rto_initial; 1757 unsigned long rto_max; 1758 unsigned long rto_min; 1759 1760 /* Maximum number of new data packets that can be sent in a burst. */ 1761 int max_burst; 1762 1763 /* This is the max_retrans value for the association. This value will 1764 * be initialized from system defaults, but can be 1765 * modified by the SCTP_ASSOCINFO socket option. 1766 */ 1767 int max_retrans; 1768 1769 /* This is the partially failed retrans value for the transport 1770 * and will be initialized from the assocs value. This can be 1771 * changed using the SCTP_PEER_ADDR_THLDS socket option 1772 */ 1773 __u16 pf_retrans; 1774 /* Used for primary path switchover. */ 1775 __u16 ps_retrans; 1776 1777 /* Maximum number of times the endpoint will retransmit INIT */ 1778 __u16 max_init_attempts; 1779 1780 /* How many times have we resent an INIT? */ 1781 __u16 init_retries; 1782 1783 /* The largest timeout or RTO value to use in attempting an INIT */ 1784 unsigned long max_init_timeo; 1785 1786 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 1787 * the destination address every heartbeat interval. This value 1788 * will be inherited by all new transports. 1789 */ 1790 unsigned long hbinterval; 1791 unsigned long probe_interval; 1792 1793 __be16 encap_port; 1794 1795 /* This is the max_retrans value for new transports in the 1796 * association. 1797 */ 1798 __u16 pathmaxrxt; 1799 1800 __u32 flowlabel; 1801 __u8 dscp; 1802 1803 /* Flag that path mtu update is pending */ 1804 __u8 pmtu_pending; 1805 1806 /* Association : The smallest PMTU discovered for all of the 1807 * PMTU : peer's transport addresses. 1808 */ 1809 __u32 pathmtu; 1810 1811 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 1812 __u32 param_flags; 1813 1814 __u32 sackfreq; 1815 /* SACK delay timeout */ 1816 unsigned long sackdelay; 1817 1818 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES]; 1819 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES]; 1820 1821 /* Transport to which SHUTDOWN chunk was last sent. */ 1822 struct sctp_transport *shutdown_last_sent_to; 1823 1824 /* Transport to which INIT chunk was last sent. */ 1825 struct sctp_transport *init_last_sent_to; 1826 1827 /* How many times have we resent a SHUTDOWN */ 1828 int shutdown_retries; 1829 1830 /* Next TSN : The next TSN number to be assigned to a new 1831 * : DATA chunk. This is sent in the INIT or INIT 1832 * : ACK chunk to the peer and incremented each 1833 * : time a DATA chunk is assigned a TSN 1834 * : (normally just prior to transmit or during 1835 * : fragmentation). 1836 */ 1837 __u32 next_tsn; 1838 1839 /* 1840 * Last Rcvd : This is the last TSN received in sequence. This value 1841 * TSN : is set initially by taking the peer's Initial TSN, 1842 * : received in the INIT or INIT ACK chunk, and 1843 * : subtracting one from it. 1844 * 1845 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point. 1846 */ 1847 1848 __u32 ctsn_ack_point; 1849 1850 /* PR-SCTP Advanced.Peer.Ack.Point */ 1851 __u32 adv_peer_ack_point; 1852 1853 /* Highest TSN that is acknowledged by incoming SACKs. */ 1854 __u32 highest_sacked; 1855 1856 /* TSN marking the fast recovery exit point */ 1857 __u32 fast_recovery_exit; 1858 1859 /* Flag to track the current fast recovery state */ 1860 __u8 fast_recovery; 1861 1862 /* The number of unacknowledged data chunks. Reported through 1863 * the SCTP_STATUS sockopt. 1864 */ 1865 __u16 unack_data; 1866 1867 /* The total number of data chunks that we've had to retransmit 1868 * as the result of a T3 timer expiration 1869 */ 1870 __u32 rtx_data_chunks; 1871 1872 /* This is the association's receive buffer space. This value is used 1873 * to set a_rwnd field in an INIT or a SACK chunk. 1874 */ 1875 __u32 rwnd; 1876 1877 /* This is the last advertised value of rwnd over a SACK chunk. */ 1878 __u32 a_rwnd; 1879 1880 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed 1881 * to slop over a maximum of the association's frag_point. 1882 */ 1883 __u32 rwnd_over; 1884 1885 /* Keeps treack of rwnd pressure. This happens when we have 1886 * a window, but not receive buffer (i.e small packets). This one 1887 * is releases slowly (1 PMTU at a time ). 1888 */ 1889 __u32 rwnd_press; 1890 1891 /* This is the sndbuf size in use for the association. 1892 * This corresponds to the sndbuf size for the association, 1893 * as specified in the sk->sndbuf. 1894 */ 1895 int sndbuf_used; 1896 1897 /* This is the amount of memory that this association has allocated 1898 * in the receive path at any given time. 1899 */ 1900 atomic_t rmem_alloc; 1901 1902 /* This is the wait queue head for send requests waiting on 1903 * the association sndbuf space. 1904 */ 1905 wait_queue_head_t wait; 1906 1907 /* The message size at which SCTP fragmentation will occur. */ 1908 __u32 frag_point; 1909 __u32 user_frag; 1910 1911 /* Counter used to count INIT errors. */ 1912 int init_err_counter; 1913 1914 /* Count the number of INIT cycles (for doubling timeout). */ 1915 int init_cycle; 1916 1917 /* Default send parameters. */ 1918 __u16 default_stream; 1919 __u16 default_flags; 1920 __u32 default_ppid; 1921 __u32 default_context; 1922 __u32 default_timetolive; 1923 1924 /* Default receive parameters */ 1925 __u32 default_rcv_context; 1926 1927 /* Stream arrays */ 1928 struct sctp_stream stream; 1929 1930 /* All outbound chunks go through this structure. */ 1931 struct sctp_outq outqueue; 1932 1933 /* A smart pipe that will handle reordering and fragmentation, 1934 * as well as handle passing events up to the ULP. 1935 */ 1936 struct sctp_ulpq ulpq; 1937 1938 /* Last TSN that caused an ECNE Chunk to be sent. */ 1939 __u32 last_ecne_tsn; 1940 1941 /* Last TSN that caused a CWR Chunk to be sent. */ 1942 __u32 last_cwr_tsn; 1943 1944 /* How many duplicated TSNs have we seen? */ 1945 int numduptsns; 1946 1947 /* These are to support 1948 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses 1949 * and Enforcement of Flow and Message Limits" 1950 * <draft-ietf-tsvwg-addip-sctp-02.txt> 1951 * or "ADDIP" for short. 1952 */ 1953 1954 1955 1956 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1957 * 1958 * R1) One and only one ASCONF Chunk MAY be in transit and 1959 * unacknowledged at any one time. If a sender, after sending 1960 * an ASCONF chunk, decides it needs to transfer another 1961 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1962 * returns from the previous ASCONF Chunk before sending a 1963 * subsequent ASCONF. Note this restriction binds each side, 1964 * so at any time two ASCONF may be in-transit on any given 1965 * association (one sent from each endpoint). 1966 * 1967 * [This is our one-and-only-one ASCONF in flight. If we do 1968 * not have an ASCONF in flight, this is NULL.] 1969 */ 1970 struct sctp_chunk *addip_last_asconf; 1971 1972 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk. 1973 * 1974 * This is needed to implement items E1 - E4 of the updated 1975 * spec. Here is the justification: 1976 * 1977 * Since the peer may bundle multiple ASCONF chunks toward us, 1978 * we now need the ability to cache multiple ACKs. The section 1979 * describes in detail how they are cached and cleaned up. 1980 */ 1981 struct list_head asconf_ack_list; 1982 1983 /* These ASCONF chunks are waiting to be sent. 1984 * 1985 * These chunks can't be pushed to outqueue until receiving 1986 * ASCONF_ACK for the previous ASCONF indicated by 1987 * addip_last_asconf, so as to guarantee that only one ASCONF 1988 * is in flight at any time. 1989 * 1990 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1991 * 1992 * In defining the ASCONF Chunk transfer procedures, it is 1993 * essential that these transfers MUST NOT cause congestion 1994 * within the network. To achieve this, we place these 1995 * restrictions on the transfer of ASCONF Chunks: 1996 * 1997 * R1) One and only one ASCONF Chunk MAY be in transit and 1998 * unacknowledged at any one time. If a sender, after sending 1999 * an ASCONF chunk, decides it needs to transfer another 2000 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 2001 * returns from the previous ASCONF Chunk before sending a 2002 * subsequent ASCONF. Note this restriction binds each side, 2003 * so at any time two ASCONF may be in-transit on any given 2004 * association (one sent from each endpoint). 2005 * 2006 * 2007 * [I really think this is EXACTLY the sort of intelligence 2008 * which already resides in sctp_outq. Please move this 2009 * queue and its supporting logic down there. --piggy] 2010 */ 2011 struct list_head addip_chunk_list; 2012 2013 /* ADDIP Section 4.1 ASCONF Chunk Procedures 2014 * 2015 * A2) A serial number should be assigned to the Chunk. The 2016 * serial number SHOULD be a monotonically increasing 2017 * number. The serial number SHOULD be initialized at 2018 * the start of the association to the same value as the 2019 * Initial TSN and every time a new ASCONF chunk is created 2020 * it is incremented by one after assigning the serial number 2021 * to the newly created chunk. 2022 * 2023 * ADDIP 2024 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF) 2025 * 2026 * Serial Number : 32 bits (unsigned integer) 2027 * 2028 * This value represents a Serial Number for the ASCONF 2029 * Chunk. The valid range of Serial Number is from 0 to 2030 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0 2031 * after reaching 4294967295. 2032 */ 2033 __u32 addip_serial; 2034 int src_out_of_asoc_ok; 2035 union sctp_addr *asconf_addr_del_pending; 2036 struct sctp_transport *new_transport; 2037 2038 /* SCTP AUTH: list of the endpoint shared keys. These 2039 * keys are provided out of band by the user application 2040 * and can't change during the lifetime of the association 2041 */ 2042 struct list_head endpoint_shared_keys; 2043 2044 /* SCTP AUTH: 2045 * The current generated association shared key (secret) 2046 */ 2047 struct sctp_auth_bytes *asoc_shared_key; 2048 struct sctp_shared_key *shkey; 2049 2050 /* SCTP AUTH: hmac id of the first peer requested algorithm 2051 * that we support. 2052 */ 2053 __u16 default_hmac_id; 2054 2055 __u16 active_key_id; 2056 2057 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */ 2058 temp:1, /* Is it a temporary association? */ 2059 pf_expose:2, /* Expose pf state? */ 2060 force_delay:1; 2061 2062 __u8 strreset_enable; 2063 __u8 strreset_outstanding; /* request param count on the fly */ 2064 2065 __u32 strreset_outseq; /* Update after receiving response */ 2066 __u32 strreset_inseq; /* Update after receiving request */ 2067 __u32 strreset_result[2]; /* save the results of last 2 responses */ 2068 2069 struct sctp_chunk *strreset_chunk; /* save request chunk */ 2070 2071 struct sctp_priv_assoc_stats stats; 2072 2073 int sent_cnt_removable; 2074 2075 __u16 subscribe; 2076 2077 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 2078 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 2079 2080 /* Security identifiers from incoming (INIT). These are set by 2081 * security_sctp_assoc_request(). These will only be used by 2082 * SCTP TCP type sockets and peeled off connections as they 2083 * cause a new socket to be generated. security_sctp_sk_clone() 2084 * will then plug these into the new socket. 2085 */ 2086 2087 u32 secid; 2088 u32 peer_secid; 2089 2090 struct rcu_head rcu; 2091 }; 2092 2093 2094 /* An eyecatcher for determining if we are really looking at an 2095 * association data structure. 2096 */ 2097 enum { 2098 SCTP_ASSOC_EYECATCHER = 0xa550c123, 2099 }; 2100 2101 /* Recover the outer association structure. */ 2102 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base) 2103 { 2104 struct sctp_association *asoc; 2105 2106 asoc = container_of(base, struct sctp_association, base); 2107 return asoc; 2108 } 2109 2110 /* These are function signatures for manipulating associations. */ 2111 2112 2113 struct sctp_association * 2114 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk, 2115 enum sctp_scope scope, gfp_t gfp); 2116 void sctp_association_free(struct sctp_association *); 2117 void sctp_association_put(struct sctp_association *); 2118 void sctp_association_hold(struct sctp_association *); 2119 2120 struct sctp_transport *sctp_assoc_choose_alter_transport( 2121 struct sctp_association *, struct sctp_transport *); 2122 void sctp_assoc_update_retran_path(struct sctp_association *); 2123 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *, 2124 const union sctp_addr *); 2125 int sctp_assoc_lookup_laddr(struct sctp_association *asoc, 2126 const union sctp_addr *laddr); 2127 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *, 2128 const union sctp_addr *address, 2129 const gfp_t gfp, 2130 const int peer_state); 2131 void sctp_assoc_rm_peer(struct sctp_association *asoc, 2132 struct sctp_transport *peer); 2133 void sctp_assoc_control_transport(struct sctp_association *asoc, 2134 struct sctp_transport *transport, 2135 enum sctp_transport_cmd command, 2136 sctp_sn_error_t error); 2137 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32); 2138 void sctp_assoc_migrate(struct sctp_association *, struct sock *); 2139 int sctp_assoc_update(struct sctp_association *old, 2140 struct sctp_association *new); 2141 2142 __u32 sctp_association_get_next_tsn(struct sctp_association *); 2143 2144 void sctp_assoc_update_frag_point(struct sctp_association *asoc); 2145 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu); 2146 void sctp_assoc_sync_pmtu(struct sctp_association *asoc); 2147 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int); 2148 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int); 2149 void sctp_assoc_set_primary(struct sctp_association *, 2150 struct sctp_transport *); 2151 void sctp_assoc_del_nonprimary_peers(struct sctp_association *, 2152 struct sctp_transport *); 2153 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, 2154 enum sctp_scope scope, gfp_t gfp); 2155 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *, 2156 struct sctp_cookie*, 2157 gfp_t gfp); 2158 int sctp_assoc_set_id(struct sctp_association *, gfp_t); 2159 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc); 2160 struct sctp_chunk *sctp_assoc_lookup_asconf_ack( 2161 const struct sctp_association *asoc, 2162 __be32 serial); 2163 void sctp_asconf_queue_teardown(struct sctp_association *asoc); 2164 2165 int sctp_cmp_addr_exact(const union sctp_addr *ss1, 2166 const union sctp_addr *ss2); 2167 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc); 2168 2169 /* A convenience structure to parse out SCTP specific CMSGs. */ 2170 struct sctp_cmsgs { 2171 struct sctp_initmsg *init; 2172 struct sctp_sndrcvinfo *srinfo; 2173 struct sctp_sndinfo *sinfo; 2174 struct sctp_prinfo *prinfo; 2175 struct sctp_authinfo *authinfo; 2176 struct msghdr *addrs_msg; 2177 }; 2178 2179 /* Structure for tracking memory objects */ 2180 struct sctp_dbg_objcnt_entry { 2181 char *label; 2182 atomic_t *counter; 2183 }; 2184 2185 #endif /* __sctp_structs_h__ */ 2186