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 struct sock *(*create_accept_sk) (struct sock *sk, 501 struct sctp_association *asoc, 502 bool kern); 503 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr); 504 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk); 505 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk); 506 void (*copy_ip_options)(struct sock *sk, struct sock *newsk); 507 struct sctp_af *af; 508 }; 509 510 511 /* Structure to track chunk fragments that have been acked, but peer 512 * fragments of the same message have not. 513 */ 514 struct sctp_datamsg { 515 /* Chunks waiting to be submitted to lower layer. */ 516 struct list_head chunks; 517 /* Reference counting. */ 518 refcount_t refcnt; 519 /* When is this message no longer interesting to the peer? */ 520 unsigned long expires_at; 521 /* Did the message fail to send? */ 522 int send_error; 523 u8 send_failed:1, 524 can_delay:1, /* should this message be Nagle delayed */ 525 abandoned:1; /* should this message be abandoned */ 526 }; 527 528 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *, 529 struct sctp_sndrcvinfo *, 530 struct iov_iter *); 531 void sctp_datamsg_free(struct sctp_datamsg *); 532 void sctp_datamsg_put(struct sctp_datamsg *); 533 void sctp_chunk_fail(struct sctp_chunk *, int error); 534 int sctp_chunk_abandoned(struct sctp_chunk *); 535 536 /* RFC2960 1.4 Key Terms 537 * 538 * o Chunk: A unit of information within an SCTP packet, consisting of 539 * a chunk header and chunk-specific content. 540 * 541 * As a matter of convenience, we remember the SCTP common header for 542 * each chunk as well as a few other header pointers... 543 */ 544 struct sctp_chunk { 545 struct list_head list; 546 547 refcount_t refcnt; 548 549 /* How many times this chunk have been sent, for prsctp RTX policy */ 550 int sent_count; 551 552 union { 553 /* This is our link to the per-transport transmitted list. */ 554 struct list_head transmitted_list; 555 /* List in specific stream outq */ 556 struct list_head stream_list; 557 }; 558 559 /* This field is used by chunks that hold fragmented data. 560 * For the first fragment this is the list that holds the rest of 561 * fragments. For the remaining fragments, this is the link to the 562 * frag_list maintained in the first fragment. 563 */ 564 struct list_head frag_list; 565 566 /* This points to the sk_buff containing the actual data. */ 567 struct sk_buff *skb; 568 569 union { 570 /* In case of GSO packets, this will store the head one */ 571 struct sk_buff *head_skb; 572 /* In case of auth enabled, this will point to the shkey */ 573 struct sctp_shared_key *shkey; 574 }; 575 576 /* These are the SCTP headers by reverse order in a packet. 577 * Note that some of these may happen more than once. In that 578 * case, we point at the "current" one, whatever that means 579 * for that level of header. 580 */ 581 582 /* We point this at the FIRST TLV parameter to chunk_hdr. */ 583 union sctp_params param_hdr; 584 union { 585 __u8 *v; 586 struct sctp_datahdr *data_hdr; 587 struct sctp_inithdr *init_hdr; 588 struct sctp_sackhdr *sack_hdr; 589 struct sctp_heartbeathdr *hb_hdr; 590 struct sctp_sender_hb_info *hbs_hdr; 591 struct sctp_shutdownhdr *shutdown_hdr; 592 struct sctp_signed_cookie *cookie_hdr; 593 struct sctp_ecnehdr *ecne_hdr; 594 struct sctp_cwrhdr *ecn_cwr_hdr; 595 struct sctp_errhdr *err_hdr; 596 struct sctp_addiphdr *addip_hdr; 597 struct sctp_fwdtsn_hdr *fwdtsn_hdr; 598 struct sctp_authhdr *auth_hdr; 599 struct sctp_idatahdr *idata_hdr; 600 struct sctp_ifwdtsn_hdr *ifwdtsn_hdr; 601 } subh; 602 603 __u8 *chunk_end; 604 605 struct sctp_chunkhdr *chunk_hdr; 606 struct sctphdr *sctp_hdr; 607 608 /* This needs to be recoverable for SCTP_SEND_FAILED events. */ 609 struct sctp_sndrcvinfo sinfo; 610 611 /* Which association does this belong to? */ 612 struct sctp_association *asoc; 613 614 /* What endpoint received this chunk? */ 615 struct sctp_ep_common *rcvr; 616 617 /* We fill this in if we are calculating RTT. */ 618 unsigned long sent_at; 619 620 /* What is the origin IP address for this chunk? */ 621 union sctp_addr source; 622 /* Destination address for this chunk. */ 623 union sctp_addr dest; 624 625 /* For outbound message, track all fragments for SEND_FAILED. */ 626 struct sctp_datamsg *msg; 627 628 /* For an inbound chunk, this tells us where it came from. 629 * For an outbound chunk, it tells us where we'd like it to 630 * go. It is NULL if we have no preference. 631 */ 632 struct sctp_transport *transport; 633 634 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO 635 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH 636 * spec violates the principle premis that all chunks are processed 637 * in order. 638 */ 639 struct sk_buff *auth_chunk; 640 641 #define SCTP_CAN_FRTX 0x0 642 #define SCTP_NEED_FRTX 0x1 643 #define SCTP_DONT_FRTX 0x2 644 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */ 645 has_tsn:1, /* Does this chunk have a TSN yet? */ 646 has_ssn:1, /* Does this chunk have a SSN yet? */ 647 #define has_mid has_ssn 648 singleton:1, /* Only chunk in the packet? */ 649 end_of_packet:1, /* Last chunk in the packet? */ 650 ecn_ce_done:1, /* Have we processed the ECN CE bit? */ 651 pdiscard:1, /* Discard the whole packet now? */ 652 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */ 653 data_accepted:1, /* At least 1 chunk accepted */ 654 auth:1, /* IN: was auth'ed | OUT: needs auth */ 655 has_asconf:1, /* IN: have seen an asconf before */ 656 pmtu_probe:1, /* Used by PLPMTUD, can be set in s HB chunk */ 657 tsn_missing_report:2, /* Data chunk missing counter. */ 658 fast_retransmit:2; /* Is this chunk fast retransmitted? */ 659 }; 660 661 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1) 662 void sctp_chunk_hold(struct sctp_chunk *); 663 void sctp_chunk_put(struct sctp_chunk *); 664 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len, 665 struct iov_iter *from); 666 void sctp_chunk_free(struct sctp_chunk *); 667 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data); 668 struct sctp_chunk *sctp_chunkify(struct sk_buff *, 669 const struct sctp_association *, 670 struct sock *, gfp_t gfp); 671 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *, 672 union sctp_addr *); 673 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk); 674 675 static inline __u16 sctp_chunk_stream_no(struct sctp_chunk *ch) 676 { 677 return ntohs(ch->subh.data_hdr->stream); 678 } 679 680 enum { 681 SCTP_ADDR_NEW, /* new address added to assoc/ep */ 682 SCTP_ADDR_SRC, /* address can be used as source */ 683 SCTP_ADDR_DEL, /* address about to be deleted */ 684 }; 685 686 /* This is a structure for holding either an IPv6 or an IPv4 address. */ 687 struct sctp_sockaddr_entry { 688 struct list_head list; 689 struct rcu_head rcu; 690 union sctp_addr a; 691 __u8 state; 692 __u8 valid; 693 }; 694 695 #define SCTP_ADDRESS_TICK_DELAY 500 696 697 /* This structure holds lists of chunks as we are assembling for 698 * transmission. 699 */ 700 struct sctp_packet { 701 /* These are the SCTP header values (host order) for the packet. */ 702 __u16 source_port; 703 __u16 destination_port; 704 __u32 vtag; 705 706 /* This contains the payload chunks. */ 707 struct list_head chunk_list; 708 709 /* This is the overhead of the sctp and ip headers. */ 710 size_t overhead; 711 /* This is the total size of all chunks INCLUDING padding. */ 712 size_t size; 713 /* This is the maximum size this packet may have */ 714 size_t max_size; 715 716 /* The packet is destined for this transport address. 717 * The function we finally use to pass down to the next lower 718 * layer lives in the transport structure. 719 */ 720 struct sctp_transport *transport; 721 722 /* pointer to the auth chunk for this packet */ 723 struct sctp_chunk *auth; 724 725 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */ 726 has_sack:1, /* This packet contains a SACK chunk. */ 727 has_auth:1, /* This packet contains an AUTH chunk */ 728 has_data:1, /* This packet contains at least 1 DATA chunk */ 729 ipfragok:1; /* So let ip fragment this packet */ 730 }; 731 732 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *, 733 __u16 sport, __u16 dport); 734 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int); 735 enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet, 736 struct sctp_chunk *chunk, 737 int one_packet, gfp_t gfp); 738 enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet, 739 struct sctp_chunk *chunk); 740 int sctp_packet_transmit(struct sctp_packet *, gfp_t); 741 void sctp_packet_free(struct sctp_packet *); 742 743 static inline int sctp_packet_empty(struct sctp_packet *packet) 744 { 745 return packet->size == packet->overhead; 746 } 747 748 /* This represents a remote transport address. 749 * For local transport addresses, we just use union sctp_addr. 750 * 751 * RFC2960 Section 1.4 Key Terms 752 * 753 * o Transport address: A Transport Address is traditionally defined 754 * by Network Layer address, Transport Layer protocol and Transport 755 * Layer port number. In the case of SCTP running over IP, a 756 * transport address is defined by the combination of an IP address 757 * and an SCTP port number (where SCTP is the Transport protocol). 758 * 759 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control 760 * 761 * o The sender keeps a separate congestion control parameter set for 762 * each of the destination addresses it can send to (not each 763 * source-destination pair but for each destination). The parameters 764 * should decay if the address is not used for a long enough time 765 * period. 766 * 767 */ 768 struct sctp_transport { 769 /* A list of transports. */ 770 struct list_head transports; 771 struct rhlist_head node; 772 773 /* Reference counting. */ 774 refcount_t refcnt; 775 __u32 dead:1, 776 /* RTO-Pending : A flag used to track if one of the DATA 777 * chunks sent to this address is currently being 778 * used to compute a RTT. If this flag is 0, 779 * the next DATA chunk sent to this destination 780 * should be used to compute a RTT and this flag 781 * should be set. Every time the RTT 782 * calculation completes (i.e. the DATA chunk 783 * is SACK'd) clear this flag. 784 */ 785 rto_pending:1, 786 787 /* 788 * hb_sent : a flag that signals that we have a pending 789 * heartbeat. 790 */ 791 hb_sent:1, 792 793 /* Is the Path MTU update pending on this transport */ 794 pmtu_pending:1, 795 796 dst_pending_confirm:1, /* need to confirm neighbour */ 797 798 /* Has this transport moved the ctsn since we last sacked */ 799 sack_generation:1; 800 u32 dst_cookie; 801 802 struct flowi fl; 803 804 /* This is the peer's IP address and port. */ 805 union sctp_addr ipaddr; 806 807 /* These are the functions we call to handle LLP stuff. */ 808 struct sctp_af *af_specific; 809 810 /* Which association do we belong to? */ 811 struct sctp_association *asoc; 812 813 /* RFC2960 814 * 815 * 12.3 Per Transport Address Data 816 * 817 * For each destination transport address in the peer's 818 * address list derived from the INIT or INIT ACK chunk, a 819 * number of data elements needs to be maintained including: 820 */ 821 /* RTO : The current retransmission timeout value. */ 822 unsigned long rto; 823 824 __u32 rtt; /* This is the most recent RTT. */ 825 826 /* RTTVAR : The current RTT variation. */ 827 __u32 rttvar; 828 829 /* SRTT : The current smoothed round trip time. */ 830 __u32 srtt; 831 832 /* 833 * These are the congestion stats. 834 */ 835 /* cwnd : The current congestion window. */ 836 __u32 cwnd; /* This is the actual cwnd. */ 837 838 /* ssthresh : The current slow start threshold value. */ 839 __u32 ssthresh; 840 841 /* partial : The tracking method for increase of cwnd when in 842 * bytes acked : congestion avoidance mode (see Section 6.2.2) 843 */ 844 __u32 partial_bytes_acked; 845 846 /* Data that has been sent, but not acknowledged. */ 847 __u32 flight_size; 848 849 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */ 850 851 /* Destination */ 852 struct dst_entry *dst; 853 /* Source address. */ 854 union sctp_addr saddr; 855 856 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 857 * the destination address every heartbeat interval. 858 */ 859 unsigned long hbinterval; 860 unsigned long probe_interval; 861 862 /* SACK delay timeout */ 863 unsigned long sackdelay; 864 __u32 sackfreq; 865 866 atomic_t mtu_info; 867 868 /* When was the last time that we heard from this transport? We use 869 * this to pick new active and retran paths. 870 */ 871 ktime_t last_time_heard; 872 873 /* When was the last time that we sent a chunk using this 874 * transport? We use this to check for idle transports 875 */ 876 unsigned long last_time_sent; 877 878 /* Last time(in jiffies) when cwnd is reduced due to the congestion 879 * indication based on ECNE chunk. 880 */ 881 unsigned long last_time_ecne_reduced; 882 883 __be16 encap_port; 884 885 /* This is the max_retrans value for the transport and will 886 * be initialized from the assocs value. This can be changed 887 * using the SCTP_SET_PEER_ADDR_PARAMS socket option. 888 */ 889 __u16 pathmaxrxt; 890 891 __u32 flowlabel; 892 __u8 dscp; 893 894 /* This is the partially failed retrans value for the transport 895 * and will be initialized from the assocs value. This can be changed 896 * using the SCTP_PEER_ADDR_THLDS socket option 897 */ 898 __u16 pf_retrans; 899 /* Used for primary path switchover. */ 900 __u16 ps_retrans; 901 /* PMTU : The current known path MTU. */ 902 __u32 pathmtu; 903 904 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 905 __u32 param_flags; 906 907 /* The number of times INIT has been sent on this transport. */ 908 int init_sent_count; 909 910 /* state : The current state of this destination, 911 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN. 912 */ 913 int state; 914 915 /* These are the error stats for this destination. */ 916 917 /* Error count : The current error count for this destination. */ 918 unsigned short error_count; 919 920 /* Per : A timer used by each destination. 921 * Destination : 922 * Timer : 923 * 924 * [Everywhere else in the text this is called T3-rtx. -ed] 925 */ 926 struct timer_list T3_rtx_timer; 927 928 /* Heartbeat timer is per destination. */ 929 struct timer_list hb_timer; 930 931 /* Timer to handle ICMP proto unreachable envets */ 932 struct timer_list proto_unreach_timer; 933 934 /* Timer to handler reconf chunk rtx */ 935 struct timer_list reconf_timer; 936 937 /* Timer to send a probe HB packet for PLPMTUD */ 938 struct timer_list probe_timer; 939 940 /* Since we're using per-destination retransmission timers 941 * (see above), we're also using per-destination "transmitted" 942 * queues. This probably ought to be a private struct 943 * accessible only within the outqueue, but it's not, yet. 944 */ 945 struct list_head transmitted; 946 947 /* We build bundle-able packets for this transport here. */ 948 struct sctp_packet packet; 949 950 /* This is the list of transports that have chunks to send. */ 951 struct list_head send_ready; 952 953 /* State information saved for SFR_CACC algorithm. The key 954 * idea in SFR_CACC is to maintain state at the sender on a 955 * per-destination basis when a changeover happens. 956 * char changeover_active; 957 * char cycling_changeover; 958 * __u32 next_tsn_at_change; 959 * char cacc_saw_newack; 960 */ 961 struct { 962 /* An unsigned integer, which stores the next TSN to be 963 * used by the sender, at the moment of changeover. 964 */ 965 __u32 next_tsn_at_change; 966 967 /* A flag which indicates the occurrence of a changeover */ 968 char changeover_active; 969 970 /* A flag which indicates whether the change of primary is 971 * the first switch to this destination address during an 972 * active switch. 973 */ 974 char cycling_changeover; 975 976 /* A temporary flag, which is used during the processing of 977 * a SACK to estimate the causative TSN(s)'s group. 978 */ 979 char cacc_saw_newack; 980 } cacc; 981 982 struct { 983 __u16 pmtu; 984 __u16 probe_size; 985 __u16 probe_high; 986 __u8 probe_count; 987 __u8 state; 988 } pl; /* plpmtud related */ 989 990 /* 64-bit random number sent with heartbeat. */ 991 __u64 hb_nonce; 992 993 struct rcu_head rcu; 994 }; 995 996 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *, 997 gfp_t); 998 void sctp_transport_set_owner(struct sctp_transport *, 999 struct sctp_association *); 1000 void sctp_transport_route(struct sctp_transport *, union sctp_addr *, 1001 struct sctp_sock *); 1002 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk); 1003 void sctp_transport_free(struct sctp_transport *); 1004 void sctp_transport_reset_t3_rtx(struct sctp_transport *); 1005 void sctp_transport_reset_hb_timer(struct sctp_transport *); 1006 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport); 1007 void sctp_transport_reset_probe_timer(struct sctp_transport *transport); 1008 void sctp_transport_reset_raise_timer(struct sctp_transport *transport); 1009 int sctp_transport_hold(struct sctp_transport *); 1010 void sctp_transport_put(struct sctp_transport *); 1011 void sctp_transport_update_rto(struct sctp_transport *, __u32); 1012 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32); 1013 void sctp_transport_lower_cwnd(struct sctp_transport *t, 1014 enum sctp_lower_cwnd reason); 1015 void sctp_transport_burst_limited(struct sctp_transport *); 1016 void sctp_transport_burst_reset(struct sctp_transport *); 1017 unsigned long sctp_transport_timeout(struct sctp_transport *); 1018 void sctp_transport_reset(struct sctp_transport *t); 1019 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu); 1020 void sctp_transport_immediate_rtx(struct sctp_transport *); 1021 void sctp_transport_dst_release(struct sctp_transport *t); 1022 void sctp_transport_dst_confirm(struct sctp_transport *t); 1023 void sctp_transport_pl_send(struct sctp_transport *t); 1024 bool sctp_transport_pl_recv(struct sctp_transport *t); 1025 1026 1027 /* This is the structure we use to queue packets as they come into 1028 * SCTP. We write packets to it and read chunks from it. 1029 */ 1030 struct sctp_inq { 1031 /* This is actually a queue of sctp_chunk each 1032 * containing a partially decoded packet. 1033 */ 1034 struct list_head in_chunk_list; 1035 /* This is the packet which is currently off the in queue and is 1036 * being worked on through the inbound chunk processing. 1037 */ 1038 struct sctp_chunk *in_progress; 1039 1040 /* This is the delayed task to finish delivering inbound 1041 * messages. 1042 */ 1043 struct work_struct immediate; 1044 }; 1045 1046 void sctp_inq_init(struct sctp_inq *); 1047 void sctp_inq_free(struct sctp_inq *); 1048 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet); 1049 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *); 1050 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *); 1051 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t); 1052 1053 /* This is the structure we use to hold outbound chunks. You push 1054 * chunks in and they automatically pop out the other end as bundled 1055 * packets (it calls (*output_handler)()). 1056 * 1057 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1, 1058 * and 8.2 of the v13 draft. 1059 * 1060 * It handles retransmissions. The connection to the timeout portion 1061 * of the state machine is through sctp_..._timeout() and timeout_handler. 1062 * 1063 * If you feed it SACKs, it will eat them. 1064 * 1065 * If you give it big chunks, it will fragment them. 1066 * 1067 * It assigns TSN's to data chunks. This happens at the last possible 1068 * instant before transmission. 1069 * 1070 * When free()'d, it empties itself out via output_handler(). 1071 */ 1072 struct sctp_outq { 1073 struct sctp_association *asoc; 1074 1075 /* Data pending that has never been transmitted. */ 1076 struct list_head out_chunk_list; 1077 1078 /* Stream scheduler being used */ 1079 struct sctp_sched_ops *sched; 1080 1081 unsigned int out_qlen; /* Total length of queued data chunks. */ 1082 1083 /* Error of send failed, may used in SCTP_SEND_FAILED event. */ 1084 unsigned int error; 1085 1086 /* These are control chunks we want to send. */ 1087 struct list_head control_chunk_list; 1088 1089 /* These are chunks that have been sacked but are above the 1090 * CTSN, or cumulative tsn ack point. 1091 */ 1092 struct list_head sacked; 1093 1094 /* Put chunks on this list to schedule them for 1095 * retransmission. 1096 */ 1097 struct list_head retransmit; 1098 1099 /* Put chunks on this list to save them for FWD TSN processing as 1100 * they were abandoned. 1101 */ 1102 struct list_head abandoned; 1103 1104 /* How many unackd bytes do we have in-flight? */ 1105 __u32 outstanding_bytes; 1106 1107 /* Are we doing fast-rtx on this queue */ 1108 char fast_rtx; 1109 1110 /* Corked? */ 1111 char cork; 1112 }; 1113 1114 void sctp_outq_init(struct sctp_association *, struct sctp_outq *); 1115 void sctp_outq_teardown(struct sctp_outq *); 1116 void sctp_outq_free(struct sctp_outq*); 1117 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t); 1118 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *); 1119 int sctp_outq_is_empty(const struct sctp_outq *); 1120 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport, 1121 enum sctp_retransmit_reason reason); 1122 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8); 1123 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp); 1124 void sctp_prsctp_prune(struct sctp_association *asoc, 1125 struct sctp_sndrcvinfo *sinfo, int msg_len); 1126 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn); 1127 /* Uncork and flush an outqueue. */ 1128 static inline void sctp_outq_cork(struct sctp_outq *q) 1129 { 1130 q->cork = 1; 1131 } 1132 1133 /* SCTP skb control block. 1134 * sctp_input_cb is currently used on rx and sock rx queue 1135 */ 1136 struct sctp_input_cb { 1137 union { 1138 struct inet_skb_parm h4; 1139 #if IS_ENABLED(CONFIG_IPV6) 1140 struct inet6_skb_parm h6; 1141 #endif 1142 } header; 1143 struct sctp_chunk *chunk; 1144 struct sctp_af *af; 1145 __be16 encap_port; 1146 }; 1147 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0])) 1148 1149 struct sctp_output_cb { 1150 struct sk_buff *last; 1151 }; 1152 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0])) 1153 1154 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb) 1155 { 1156 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; 1157 1158 return chunk->head_skb ? : skb; 1159 } 1160 1161 /* These bind address data fields common between endpoints and associations */ 1162 struct sctp_bind_addr { 1163 1164 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1165 * 1166 * SCTP Port: The local SCTP port number the endpoint is 1167 * bound to. 1168 */ 1169 __u16 port; 1170 1171 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1172 * 1173 * Address List: The list of IP addresses that this instance 1174 * has bound. This information is passed to one's 1175 * peer(s) in INIT and INIT ACK chunks. 1176 */ 1177 struct list_head address_list; 1178 }; 1179 1180 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port); 1181 void sctp_bind_addr_free(struct sctp_bind_addr *); 1182 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest, 1183 const struct sctp_bind_addr *src, 1184 enum sctp_scope scope, gfp_t gfp, 1185 int flags); 1186 int sctp_bind_addr_dup(struct sctp_bind_addr *dest, 1187 const struct sctp_bind_addr *src, 1188 gfp_t gfp); 1189 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *, 1190 int new_size, __u8 addr_state, gfp_t gfp); 1191 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *); 1192 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *, 1193 struct sctp_sock *); 1194 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *, 1195 struct sctp_sock *, struct sctp_sock *); 1196 int sctp_bind_addr_state(const struct sctp_bind_addr *bp, 1197 const union sctp_addr *addr); 1198 int sctp_bind_addrs_check(struct sctp_sock *sp, 1199 struct sctp_sock *sp2, int cnt2); 1200 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp, 1201 const union sctp_addr *addrs, 1202 int addrcnt, 1203 struct sctp_sock *opt); 1204 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp, 1205 int *addrs_len, 1206 gfp_t gfp); 1207 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len, 1208 __u16 port, gfp_t gfp); 1209 1210 enum sctp_scope sctp_scope(const union sctp_addr *addr); 1211 int sctp_in_scope(struct net *net, const union sctp_addr *addr, 1212 const enum sctp_scope scope); 1213 int sctp_is_any(struct sock *sk, const union sctp_addr *addr); 1214 int sctp_is_ep_boundall(struct sock *sk); 1215 1216 1217 /* What type of endpoint? */ 1218 enum sctp_endpoint_type { 1219 SCTP_EP_TYPE_SOCKET, 1220 SCTP_EP_TYPE_ASSOCIATION, 1221 }; 1222 1223 /* 1224 * A common base class to bridge the implementation view of a 1225 * socket (usually listening) endpoint versus an association's 1226 * local endpoint. 1227 * This common structure is useful for several purposes: 1228 * 1) Common interface for lookup routines. 1229 * a) Subfunctions work for either endpoint or association 1230 * b) Single interface to lookup allows hiding the lookup lock rather 1231 * than acquiring it externally. 1232 * 2) Common interface for the inbound chunk handling/state machine. 1233 * 3) Common object handling routines for reference counting, etc. 1234 * 4) Disentangle association lookup from endpoint lookup, where we 1235 * do not have to find our endpoint to find our association. 1236 * 1237 */ 1238 1239 struct sctp_ep_common { 1240 /* Runtime type information. What kind of endpoint is this? */ 1241 enum sctp_endpoint_type type; 1242 1243 /* Some fields to help us manage this object. 1244 * refcnt - Reference count access to this object. 1245 * dead - Do not attempt to use this object. 1246 */ 1247 refcount_t refcnt; 1248 bool dead; 1249 1250 /* What socket does this endpoint belong to? */ 1251 struct sock *sk; 1252 1253 /* Cache netns and it won't change once set */ 1254 struct net *net; 1255 1256 /* This is where we receive inbound chunks. */ 1257 struct sctp_inq inqueue; 1258 1259 /* This substructure includes the defining parameters of the 1260 * endpoint: 1261 * bind_addr.port is our shared port number. 1262 * bind_addr.address_list is our set of local IP addresses. 1263 */ 1264 struct sctp_bind_addr bind_addr; 1265 }; 1266 1267 1268 /* RFC Section 1.4 Key Terms 1269 * 1270 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a 1271 * multi-homed host, an SCTP endpoint is represented to its peers as a 1272 * combination of a set of eligible destination transport addresses to 1273 * which SCTP packets can be sent and a set of eligible source 1274 * transport addresses from which SCTP packets can be received. 1275 * All transport addresses used by an SCTP endpoint must use the 1276 * same port number, but can use multiple IP addresses. A transport 1277 * address used by an SCTP endpoint must not be used by another 1278 * SCTP endpoint. In other words, a transport address is unique 1279 * to an SCTP endpoint. 1280 * 1281 * From an implementation perspective, each socket has one of these. 1282 * A TCP-style socket will have exactly one association on one of 1283 * these. An UDP-style socket will have multiple associations hanging 1284 * off one of these. 1285 */ 1286 1287 struct sctp_endpoint { 1288 /* Common substructure for endpoint and association. */ 1289 struct sctp_ep_common base; 1290 1291 /* Fields to help us manage our entries in the hash tables. */ 1292 struct hlist_node node; 1293 int hashent; 1294 1295 /* Associations: A list of current associations and mappings 1296 * to the data consumers for each association. This 1297 * may be in the form of a hash table or other 1298 * implementation dependent structure. The data 1299 * consumers may be process identification 1300 * information such as file descriptors, named pipe 1301 * pointer, or table pointers dependent on how SCTP 1302 * is implemented. 1303 */ 1304 /* This is really a list of struct sctp_association entries. */ 1305 struct list_head asocs; 1306 1307 /* Cookie authentication key used by this endpoint */ 1308 struct hmac_sha256_key cookie_auth_key; 1309 1310 /* sendbuf acct. policy. */ 1311 __u32 sndbuf_policy; 1312 1313 /* rcvbuf acct. policy. */ 1314 __u32 rcvbuf_policy; 1315 1316 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */ 1317 struct sctp_hmac_algo_param *auth_hmacs_list; 1318 1319 /* SCTP-AUTH: chunks to authenticate encoded into parameter */ 1320 struct sctp_chunks_param *auth_chunk_list; 1321 1322 /* SCTP-AUTH: endpoint shared keys */ 1323 struct list_head endpoint_shared_keys; 1324 __u16 active_key_id; 1325 __u8 ecn_enable:1, 1326 auth_enable:1, 1327 intl_enable:1, 1328 prsctp_enable:1, 1329 asconf_enable:1, 1330 reconf_enable:1; 1331 1332 __u8 strreset_enable; 1333 struct rcu_head rcu; 1334 }; 1335 1336 /* Recover the outer endpoint structure. */ 1337 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base) 1338 { 1339 struct sctp_endpoint *ep; 1340 1341 ep = container_of(base, struct sctp_endpoint, base); 1342 return ep; 1343 } 1344 1345 /* These are function signatures for manipulating endpoints. */ 1346 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t); 1347 void sctp_endpoint_free(struct sctp_endpoint *); 1348 void sctp_endpoint_put(struct sctp_endpoint *); 1349 int sctp_endpoint_hold(struct sctp_endpoint *ep); 1350 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *); 1351 struct sctp_association *sctp_endpoint_lookup_assoc( 1352 const struct sctp_endpoint *ep, 1353 const union sctp_addr *paddr, 1354 struct sctp_transport **); 1355 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep, 1356 const union sctp_addr *paddr); 1357 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *ep, 1358 struct net *net, 1359 const union sctp_addr *laddr, 1360 int dif, int sdif); 1361 bool sctp_has_association(struct net *net, const union sctp_addr *laddr, 1362 const union sctp_addr *paddr, int dif, int sdif); 1363 1364 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep, 1365 const struct sctp_association *asoc, 1366 enum sctp_cid cid, struct sctp_init_chunk *peer_init, 1367 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk); 1368 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk, 1369 const union sctp_addr *peer, 1370 struct sctp_init_chunk *init, gfp_t gfp); 1371 __u32 sctp_generate_tag(const struct sctp_endpoint *); 1372 __u32 sctp_generate_tsn(const struct sctp_endpoint *); 1373 1374 struct sctp_inithdr_host { 1375 __u32 init_tag; 1376 __u32 a_rwnd; 1377 __u16 num_outbound_streams; 1378 __u16 num_inbound_streams; 1379 __u32 initial_tsn; 1380 }; 1381 1382 struct sctp_stream_priorities { 1383 /* List of priorities scheduled */ 1384 struct list_head prio_sched; 1385 /* List of streams scheduled */ 1386 struct list_head active; 1387 /* The next stream in line */ 1388 struct sctp_stream_out_ext *next; 1389 __u16 prio; 1390 __u16 users; 1391 }; 1392 1393 struct sctp_stream_out_ext { 1394 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 1395 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 1396 struct list_head outq; /* chunks enqueued by this stream */ 1397 union { 1398 struct { 1399 /* Scheduled streams list */ 1400 struct list_head prio_list; 1401 struct sctp_stream_priorities *prio_head; 1402 }; 1403 /* Fields used by RR scheduler */ 1404 struct { 1405 struct list_head rr_list; 1406 }; 1407 struct { 1408 struct list_head fc_list; 1409 __u32 fc_length; 1410 __u16 fc_weight; 1411 }; 1412 }; 1413 }; 1414 1415 struct sctp_stream_out { 1416 union { 1417 __u32 mid; 1418 __u16 ssn; 1419 }; 1420 __u32 mid_uo; 1421 struct sctp_stream_out_ext *ext; 1422 __u8 state; 1423 }; 1424 1425 struct sctp_stream_in { 1426 union { 1427 __u32 mid; 1428 __u16 ssn; 1429 }; 1430 __u32 mid_uo; 1431 __u32 fsn; 1432 __u32 fsn_uo; 1433 char pd_mode; 1434 char pd_mode_uo; 1435 }; 1436 1437 struct sctp_stream { 1438 GENRADIX(struct sctp_stream_out) out; 1439 GENRADIX(struct sctp_stream_in) in; 1440 1441 __u16 outcnt; 1442 __u16 incnt; 1443 /* Current stream being sent, if any */ 1444 struct sctp_stream_out *out_curr; 1445 union { 1446 /* Fields used by priority scheduler */ 1447 struct { 1448 /* List of priorities scheduled */ 1449 struct list_head prio_list; 1450 }; 1451 /* Fields used by RR scheduler */ 1452 struct { 1453 /* List of streams scheduled */ 1454 struct list_head rr_list; 1455 /* The next stream in line */ 1456 struct sctp_stream_out_ext *rr_next; 1457 }; 1458 struct { 1459 struct list_head fc_list; 1460 }; 1461 }; 1462 struct sctp_stream_interleave *si; 1463 }; 1464 1465 static inline struct sctp_stream_out *sctp_stream_out( 1466 struct sctp_stream *stream, 1467 __u16 sid) 1468 { 1469 return genradix_ptr(&stream->out, sid); 1470 } 1471 1472 static inline struct sctp_stream_in *sctp_stream_in( 1473 struct sctp_stream *stream, 1474 __u16 sid) 1475 { 1476 return genradix_ptr(&stream->in, sid); 1477 } 1478 1479 #define SCTP_SO(s, i) sctp_stream_out((s), (i)) 1480 #define SCTP_SI(s, i) sctp_stream_in((s), (i)) 1481 1482 #define SCTP_STREAM_CLOSED 0x00 1483 #define SCTP_STREAM_OPEN 0x01 1484 1485 static inline __u16 sctp_datachk_len(const struct sctp_stream *stream) 1486 { 1487 return stream->si->data_chunk_len; 1488 } 1489 1490 static inline __u16 sctp_datahdr_len(const struct sctp_stream *stream) 1491 { 1492 return stream->si->data_chunk_len - sizeof(struct sctp_chunkhdr); 1493 } 1494 1495 static inline __u16 sctp_ftsnchk_len(const struct sctp_stream *stream) 1496 { 1497 return stream->si->ftsn_chunk_len; 1498 } 1499 1500 static inline __u16 sctp_ftsnhdr_len(const struct sctp_stream *stream) 1501 { 1502 return stream->si->ftsn_chunk_len - sizeof(struct sctp_chunkhdr); 1503 } 1504 1505 /* SCTP_GET_ASSOC_STATS counters */ 1506 struct sctp_priv_assoc_stats { 1507 /* Maximum observed rto in the association during subsequent 1508 * observations. Value is set to 0 if no RTO measurement took place 1509 * The transport where the max_rto was observed is returned in 1510 * obs_rto_ipaddr 1511 */ 1512 struct sockaddr_storage obs_rto_ipaddr; 1513 __u64 max_obs_rto; 1514 /* Total In and Out SACKs received and sent */ 1515 __u64 isacks; 1516 __u64 osacks; 1517 /* Total In and Out packets received and sent */ 1518 __u64 opackets; 1519 __u64 ipackets; 1520 /* Total retransmitted chunks */ 1521 __u64 rtxchunks; 1522 /* TSN received > next expected */ 1523 __u64 outofseqtsns; 1524 /* Duplicate Chunks received */ 1525 __u64 idupchunks; 1526 /* Gap Ack Blocks received */ 1527 __u64 gapcnt; 1528 /* Unordered data chunks sent and received */ 1529 __u64 ouodchunks; 1530 __u64 iuodchunks; 1531 /* Ordered data chunks sent and received */ 1532 __u64 oodchunks; 1533 __u64 iodchunks; 1534 /* Control chunks sent and received */ 1535 __u64 octrlchunks; 1536 __u64 ictrlchunks; 1537 }; 1538 1539 /* RFC2960 1540 * 1541 * 12. Recommended Transmission Control Block (TCB) Parameters 1542 * 1543 * This section details a recommended set of parameters that should 1544 * be contained within the TCB for an implementation. This section is 1545 * for illustrative purposes and should not be deemed as requirements 1546 * on an implementation or as an exhaustive list of all parameters 1547 * inside an SCTP TCB. Each implementation may need its own additional 1548 * parameters for optimization. 1549 */ 1550 1551 1552 /* Here we have information about each individual association. */ 1553 struct sctp_association { 1554 1555 /* A base structure common to endpoint and association. 1556 * In this context, it represents the associations's view 1557 * of the local endpoint of the association. 1558 */ 1559 struct sctp_ep_common base; 1560 1561 /* Associations on the same socket. */ 1562 struct list_head asocs; 1563 1564 /* association id. */ 1565 sctp_assoc_t assoc_id; 1566 1567 /* This is our parent endpoint. */ 1568 struct sctp_endpoint *ep; 1569 1570 /* These are those association elements needed in the cookie. */ 1571 struct sctp_cookie c; 1572 1573 /* This is all information about our peer. */ 1574 struct { 1575 /* transport_addr_list 1576 * 1577 * Peer : A list of SCTP transport addresses that the 1578 * Transport : peer is bound to. This information is derived 1579 * Address : from the INIT or INIT ACK and is used to 1580 * List : associate an inbound packet with a given 1581 * : association. Normally this information is 1582 * : hashed or keyed for quick lookup and access 1583 * : of the TCB. 1584 * : The list is also initialized with the list 1585 * : of addresses passed with the sctp_connectx() 1586 * : call. 1587 * 1588 * It is a list of SCTP_transport's. 1589 */ 1590 struct list_head transport_addr_list; 1591 1592 /* rwnd 1593 * 1594 * Peer Rwnd : Current calculated value of the peer's rwnd. 1595 */ 1596 __u32 rwnd; 1597 1598 /* transport_count 1599 * 1600 * Peer : A count of the number of peer addresses 1601 * Transport : in the Peer Transport Address List. 1602 * Address : 1603 * Count : 1604 */ 1605 __u16 transport_count; 1606 1607 /* port 1608 * The transport layer port number. 1609 */ 1610 __u16 port; 1611 1612 /* primary_path 1613 * 1614 * Primary : This is the current primary destination 1615 * Path : transport address of the peer endpoint. It 1616 * : may also specify a source transport address 1617 * : on this endpoint. 1618 * 1619 * All of these paths live on transport_addr_list. 1620 * 1621 * At the bakeoffs, we discovered that the intent of 1622 * primaryPath is that it only changes when the ULP 1623 * asks to have it changed. We add the activePath to 1624 * designate the connection we are currently using to 1625 * transmit new data and most control chunks. 1626 */ 1627 struct sctp_transport *primary_path; 1628 1629 /* Cache the primary path address here, when we 1630 * need a an address for msg_name. 1631 */ 1632 union sctp_addr primary_addr; 1633 1634 /* active_path 1635 * The path that we are currently using to 1636 * transmit new data and most control chunks. 1637 */ 1638 struct sctp_transport *active_path; 1639 1640 /* retran_path 1641 * 1642 * RFC2960 6.4 Multi-homed SCTP Endpoints 1643 * ... 1644 * Furthermore, when its peer is multi-homed, an 1645 * endpoint SHOULD try to retransmit a chunk to an 1646 * active destination transport address that is 1647 * different from the last destination address to 1648 * which the DATA chunk was sent. 1649 */ 1650 struct sctp_transport *retran_path; 1651 1652 /* Pointer to last transport I have sent on. */ 1653 struct sctp_transport *last_sent_to; 1654 1655 /* This is the last transport I have received DATA on. */ 1656 struct sctp_transport *last_data_from; 1657 1658 /* 1659 * Mapping An array of bits or bytes indicating which out of 1660 * Array order TSN's have been received (relative to the 1661 * Last Rcvd TSN). If no gaps exist, i.e. no out of 1662 * order packets have been received, this array 1663 * will be set to all zero. This structure may be 1664 * in the form of a circular buffer or bit array. 1665 * 1666 * Last Rcvd : This is the last TSN received in 1667 * TSN : sequence. This value is set initially by 1668 * : taking the peer's Initial TSN, received in 1669 * : the INIT or INIT ACK chunk, and subtracting 1670 * : one from it. 1671 * 1672 * Throughout most of the specification this is called the 1673 * "Cumulative TSN ACK Point". In this case, we 1674 * ignore the advice in 12.2 in favour of the term 1675 * used in the bulk of the text. This value is hidden 1676 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn(). 1677 */ 1678 struct sctp_tsnmap tsn_map; 1679 1680 /* This mask is used to disable sending the ASCONF chunk 1681 * with specified parameter to peer. 1682 */ 1683 __be16 addip_disabled_mask; 1684 1685 /* These are capabilities which our peer advertised. */ 1686 __u16 ecn_capable:1, /* Can peer do ECN? */ 1687 ipv4_address:1, /* Peer understands IPv4 addresses? */ 1688 ipv6_address:1, /* Peer understands IPv6 addresses? */ 1689 asconf_capable:1, /* Does peer support ADDIP? */ 1690 prsctp_capable:1, /* Can peer do PR-SCTP? */ 1691 reconf_capable:1, /* Can peer do RE-CONFIG? */ 1692 intl_capable:1, /* Can peer do INTERLEAVE */ 1693 auth_capable:1, /* Is peer doing SCTP-AUTH? */ 1694 /* sack_needed: 1695 * This flag indicates if the next received 1696 * packet is to be responded to with a 1697 * SACK. This is initialized to 0. When a packet 1698 * is received sack_cnt is incremented. If this value 1699 * reaches 2 or more, a SACK is sent and the 1700 * value is reset to 0. Note: This is used only 1701 * when no DATA chunks are received out of 1702 * order. When DATA chunks are out of order, 1703 * SACK's are not delayed (see Section 6). 1704 */ 1705 sack_needed:1, /* Do we need to sack the peer? */ 1706 sack_generation:1, 1707 zero_window_announced:1; 1708 1709 __u32 sack_cnt; 1710 1711 __u32 adaptation_ind; /* Adaptation Code point. */ 1712 1713 struct sctp_inithdr_host i; 1714 void *cookie; 1715 int cookie_len; 1716 1717 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. 1718 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the 1719 * Initial TSN Value minus 1 1720 */ 1721 __u32 addip_serial; 1722 1723 /* SCTP-AUTH: We need to know pears random number, hmac list 1724 * and authenticated chunk list. All that is part of the 1725 * cookie and these are just pointers to those locations 1726 */ 1727 struct sctp_random_param *peer_random; 1728 struct sctp_chunks_param *peer_chunks; 1729 struct sctp_hmac_algo_param *peer_hmacs; 1730 } peer; 1731 1732 /* State : A state variable indicating what state the 1733 * : association is in, i.e. COOKIE-WAIT, 1734 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING, 1735 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT. 1736 * 1737 * Note: No "CLOSED" state is illustrated since if a 1738 * association is "CLOSED" its TCB SHOULD be removed. 1739 * 1740 * In this implementation we DO have a CLOSED 1741 * state which is used during initiation and shutdown. 1742 * 1743 * State takes values from SCTP_STATE_*. 1744 */ 1745 enum sctp_state state; 1746 1747 /* Overall : The overall association error count. 1748 * Error Count : [Clear this any time I get something.] 1749 */ 1750 int overall_error_count; 1751 1752 /* The cookie life I award for any cookie. */ 1753 ktime_t cookie_life; 1754 1755 /* These are the association's initial, max, and min RTO values. 1756 * These values will be initialized by system defaults, but can 1757 * be modified via the SCTP_RTOINFO socket option. 1758 */ 1759 unsigned long rto_initial; 1760 unsigned long rto_max; 1761 unsigned long rto_min; 1762 1763 /* Maximum number of new data packets that can be sent in a burst. */ 1764 int max_burst; 1765 1766 /* This is the max_retrans value for the association. This value will 1767 * be initialized from system defaults, but can be 1768 * modified by the SCTP_ASSOCINFO socket option. 1769 */ 1770 int max_retrans; 1771 1772 /* This is the partially failed retrans value for the transport 1773 * and will be initialized from the assocs value. This can be 1774 * changed using the SCTP_PEER_ADDR_THLDS socket option 1775 */ 1776 __u16 pf_retrans; 1777 /* Used for primary path switchover. */ 1778 __u16 ps_retrans; 1779 1780 /* Maximum number of times the endpoint will retransmit INIT */ 1781 __u16 max_init_attempts; 1782 1783 /* How many times have we resent an INIT? */ 1784 __u16 init_retries; 1785 1786 /* The largest timeout or RTO value to use in attempting an INIT */ 1787 unsigned long max_init_timeo; 1788 1789 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 1790 * the destination address every heartbeat interval. This value 1791 * will be inherited by all new transports. 1792 */ 1793 unsigned long hbinterval; 1794 unsigned long probe_interval; 1795 1796 __be16 encap_port; 1797 1798 /* This is the max_retrans value for new transports in the 1799 * association. 1800 */ 1801 __u16 pathmaxrxt; 1802 1803 __u32 flowlabel; 1804 __u8 dscp; 1805 1806 /* Flag that path mtu update is pending */ 1807 __u8 pmtu_pending; 1808 1809 /* Association : The smallest PMTU discovered for all of the 1810 * PMTU : peer's transport addresses. 1811 */ 1812 __u32 pathmtu; 1813 1814 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 1815 __u32 param_flags; 1816 1817 __u32 sackfreq; 1818 /* SACK delay timeout */ 1819 unsigned long sackdelay; 1820 1821 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES]; 1822 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES]; 1823 1824 /* Transport to which SHUTDOWN chunk was last sent. */ 1825 struct sctp_transport *shutdown_last_sent_to; 1826 1827 /* Transport to which INIT chunk was last sent. */ 1828 struct sctp_transport *init_last_sent_to; 1829 1830 /* How many times have we resent a SHUTDOWN */ 1831 int shutdown_retries; 1832 1833 /* Next TSN : The next TSN number to be assigned to a new 1834 * : DATA chunk. This is sent in the INIT or INIT 1835 * : ACK chunk to the peer and incremented each 1836 * : time a DATA chunk is assigned a TSN 1837 * : (normally just prior to transmit or during 1838 * : fragmentation). 1839 */ 1840 __u32 next_tsn; 1841 1842 /* 1843 * Last Rcvd : This is the last TSN received in sequence. This value 1844 * TSN : is set initially by taking the peer's Initial TSN, 1845 * : received in the INIT or INIT ACK chunk, and 1846 * : subtracting one from it. 1847 * 1848 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point. 1849 */ 1850 1851 __u32 ctsn_ack_point; 1852 1853 /* PR-SCTP Advanced.Peer.Ack.Point */ 1854 __u32 adv_peer_ack_point; 1855 1856 /* Highest TSN that is acknowledged by incoming SACKs. */ 1857 __u32 highest_sacked; 1858 1859 /* TSN marking the fast recovery exit point */ 1860 __u32 fast_recovery_exit; 1861 1862 /* Flag to track the current fast recovery state */ 1863 __u8 fast_recovery; 1864 1865 /* The number of unacknowledged data chunks. Reported through 1866 * the SCTP_STATUS sockopt. 1867 */ 1868 __u16 unack_data; 1869 1870 /* The total number of data chunks that we've had to retransmit 1871 * as the result of a T3 timer expiration 1872 */ 1873 __u32 rtx_data_chunks; 1874 1875 /* This is the association's receive buffer space. This value is used 1876 * to set a_rwnd field in an INIT or a SACK chunk. 1877 */ 1878 __u32 rwnd; 1879 1880 /* This is the last advertised value of rwnd over a SACK chunk. */ 1881 __u32 a_rwnd; 1882 1883 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed 1884 * to slop over a maximum of the association's frag_point. 1885 */ 1886 __u32 rwnd_over; 1887 1888 /* Keeps treack of rwnd pressure. This happens when we have 1889 * a window, but not receive buffer (i.e small packets). This one 1890 * is releases slowly (1 PMTU at a time ). 1891 */ 1892 __u32 rwnd_press; 1893 1894 /* This is the sndbuf size in use for the association. 1895 * This corresponds to the sndbuf size for the association, 1896 * as specified in the sk->sndbuf. 1897 */ 1898 int sndbuf_used; 1899 1900 /* This is the amount of memory that this association has allocated 1901 * in the receive path at any given time. 1902 */ 1903 atomic_t rmem_alloc; 1904 1905 /* This is the wait queue head for send requests waiting on 1906 * the association sndbuf space. 1907 */ 1908 wait_queue_head_t wait; 1909 1910 /* The message size at which SCTP fragmentation will occur. */ 1911 __u32 frag_point; 1912 __u32 user_frag; 1913 1914 /* Counter used to count INIT errors. */ 1915 int init_err_counter; 1916 1917 /* Count the number of INIT cycles (for doubling timeout). */ 1918 int init_cycle; 1919 1920 /* Default send parameters. */ 1921 __u16 default_stream; 1922 __u16 default_flags; 1923 __u32 default_ppid; 1924 __u32 default_context; 1925 __u32 default_timetolive; 1926 1927 /* Default receive parameters */ 1928 __u32 default_rcv_context; 1929 1930 /* Stream arrays */ 1931 struct sctp_stream stream; 1932 1933 /* All outbound chunks go through this structure. */ 1934 struct sctp_outq outqueue; 1935 1936 /* A smart pipe that will handle reordering and fragmentation, 1937 * as well as handle passing events up to the ULP. 1938 */ 1939 struct sctp_ulpq ulpq; 1940 1941 /* Last TSN that caused an ECNE Chunk to be sent. */ 1942 __u32 last_ecne_tsn; 1943 1944 /* Last TSN that caused a CWR Chunk to be sent. */ 1945 __u32 last_cwr_tsn; 1946 1947 /* How many duplicated TSNs have we seen? */ 1948 int numduptsns; 1949 1950 /* These are to support 1951 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses 1952 * and Enforcement of Flow and Message Limits" 1953 * <draft-ietf-tsvwg-addip-sctp-02.txt> 1954 * or "ADDIP" for short. 1955 */ 1956 1957 1958 1959 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1960 * 1961 * R1) One and only one ASCONF Chunk MAY be in transit and 1962 * unacknowledged at any one time. If a sender, after sending 1963 * an ASCONF chunk, decides it needs to transfer another 1964 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1965 * returns from the previous ASCONF Chunk before sending a 1966 * subsequent ASCONF. Note this restriction binds each side, 1967 * so at any time two ASCONF may be in-transit on any given 1968 * association (one sent from each endpoint). 1969 * 1970 * [This is our one-and-only-one ASCONF in flight. If we do 1971 * not have an ASCONF in flight, this is NULL.] 1972 */ 1973 struct sctp_chunk *addip_last_asconf; 1974 1975 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk. 1976 * 1977 * This is needed to implement items E1 - E4 of the updated 1978 * spec. Here is the justification: 1979 * 1980 * Since the peer may bundle multiple ASCONF chunks toward us, 1981 * we now need the ability to cache multiple ACKs. The section 1982 * describes in detail how they are cached and cleaned up. 1983 */ 1984 struct list_head asconf_ack_list; 1985 1986 /* These ASCONF chunks are waiting to be sent. 1987 * 1988 * These chunks can't be pushed to outqueue until receiving 1989 * ASCONF_ACK for the previous ASCONF indicated by 1990 * addip_last_asconf, so as to guarantee that only one ASCONF 1991 * is in flight at any time. 1992 * 1993 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1994 * 1995 * In defining the ASCONF Chunk transfer procedures, it is 1996 * essential that these transfers MUST NOT cause congestion 1997 * within the network. To achieve this, we place these 1998 * restrictions on the transfer of ASCONF Chunks: 1999 * 2000 * R1) One and only one ASCONF Chunk MAY be in transit and 2001 * unacknowledged at any one time. If a sender, after sending 2002 * an ASCONF chunk, decides it needs to transfer another 2003 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 2004 * returns from the previous ASCONF Chunk before sending a 2005 * subsequent ASCONF. Note this restriction binds each side, 2006 * so at any time two ASCONF may be in-transit on any given 2007 * association (one sent from each endpoint). 2008 * 2009 * 2010 * [I really think this is EXACTLY the sort of intelligence 2011 * which already resides in sctp_outq. Please move this 2012 * queue and its supporting logic down there. --piggy] 2013 */ 2014 struct list_head addip_chunk_list; 2015 2016 /* ADDIP Section 4.1 ASCONF Chunk Procedures 2017 * 2018 * A2) A serial number should be assigned to the Chunk. The 2019 * serial number SHOULD be a monotonically increasing 2020 * number. The serial number SHOULD be initialized at 2021 * the start of the association to the same value as the 2022 * Initial TSN and every time a new ASCONF chunk is created 2023 * it is incremented by one after assigning the serial number 2024 * to the newly created chunk. 2025 * 2026 * ADDIP 2027 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF) 2028 * 2029 * Serial Number : 32 bits (unsigned integer) 2030 * 2031 * This value represents a Serial Number for the ASCONF 2032 * Chunk. The valid range of Serial Number is from 0 to 2033 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0 2034 * after reaching 4294967295. 2035 */ 2036 __u32 addip_serial; 2037 int src_out_of_asoc_ok; 2038 union sctp_addr *asconf_addr_del_pending; 2039 struct sctp_transport *new_transport; 2040 2041 /* SCTP AUTH: list of the endpoint shared keys. These 2042 * keys are provided out of band by the user application 2043 * and can't change during the lifetime of the association 2044 */ 2045 struct list_head endpoint_shared_keys; 2046 2047 /* SCTP AUTH: 2048 * The current generated association shared key (secret) 2049 */ 2050 struct sctp_auth_bytes *asoc_shared_key; 2051 struct sctp_shared_key *shkey; 2052 2053 /* SCTP AUTH: hmac id of the first peer requested algorithm 2054 * that we support. 2055 */ 2056 __u16 default_hmac_id; 2057 2058 __u16 active_key_id; 2059 2060 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */ 2061 temp:1, /* Is it a temporary association? */ 2062 pf_expose:2, /* Expose pf state? */ 2063 force_delay:1; 2064 2065 __u8 strreset_enable; 2066 __u8 strreset_outstanding; /* request param count on the fly */ 2067 2068 __u32 strreset_outseq; /* Update after receiving response */ 2069 __u32 strreset_inseq; /* Update after receiving request */ 2070 __u32 strreset_result[2]; /* save the results of last 2 responses */ 2071 2072 struct sctp_chunk *strreset_chunk; /* save request chunk */ 2073 2074 struct sctp_priv_assoc_stats stats; 2075 2076 int sent_cnt_removable; 2077 2078 __u16 subscribe; 2079 2080 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 2081 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 2082 2083 /* Security identifiers from incoming (INIT). These are set by 2084 * security_sctp_assoc_request(). These will only be used by 2085 * SCTP TCP type sockets and peeled off connections as they 2086 * cause a new socket to be generated. security_sctp_sk_clone() 2087 * will then plug these into the new socket. 2088 */ 2089 2090 u32 secid; 2091 u32 peer_secid; 2092 2093 struct rcu_head rcu; 2094 }; 2095 2096 2097 /* An eyecatcher for determining if we are really looking at an 2098 * association data structure. 2099 */ 2100 enum { 2101 SCTP_ASSOC_EYECATCHER = 0xa550c123, 2102 }; 2103 2104 /* Recover the outer association structure. */ 2105 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base) 2106 { 2107 struct sctp_association *asoc; 2108 2109 asoc = container_of(base, struct sctp_association, base); 2110 return asoc; 2111 } 2112 2113 /* These are function signatures for manipulating associations. */ 2114 2115 2116 struct sctp_association * 2117 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk, 2118 enum sctp_scope scope, gfp_t gfp); 2119 void sctp_association_free(struct sctp_association *); 2120 void sctp_association_put(struct sctp_association *); 2121 void sctp_association_hold(struct sctp_association *); 2122 2123 struct sctp_transport *sctp_assoc_choose_alter_transport( 2124 struct sctp_association *, struct sctp_transport *); 2125 void sctp_assoc_update_retran_path(struct sctp_association *); 2126 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *, 2127 const union sctp_addr *); 2128 int sctp_assoc_lookup_laddr(struct sctp_association *asoc, 2129 const union sctp_addr *laddr); 2130 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *, 2131 const union sctp_addr *address, 2132 const gfp_t gfp, 2133 const int peer_state); 2134 void sctp_assoc_rm_peer(struct sctp_association *asoc, 2135 struct sctp_transport *peer); 2136 void sctp_assoc_control_transport(struct sctp_association *asoc, 2137 struct sctp_transport *transport, 2138 enum sctp_transport_cmd command, 2139 sctp_sn_error_t error); 2140 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32); 2141 void sctp_assoc_migrate(struct sctp_association *, struct sock *); 2142 int sctp_assoc_update(struct sctp_association *old, 2143 struct sctp_association *new); 2144 2145 __u32 sctp_association_get_next_tsn(struct sctp_association *); 2146 2147 void sctp_assoc_update_frag_point(struct sctp_association *asoc); 2148 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu); 2149 void sctp_assoc_sync_pmtu(struct sctp_association *asoc); 2150 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int); 2151 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int); 2152 void sctp_assoc_set_primary(struct sctp_association *, 2153 struct sctp_transport *); 2154 void sctp_assoc_del_nonprimary_peers(struct sctp_association *, 2155 struct sctp_transport *); 2156 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, 2157 enum sctp_scope scope, gfp_t gfp); 2158 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *, 2159 struct sctp_cookie*, 2160 gfp_t gfp); 2161 int sctp_assoc_set_id(struct sctp_association *, gfp_t); 2162 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc); 2163 struct sctp_chunk *sctp_assoc_lookup_asconf_ack( 2164 const struct sctp_association *asoc, 2165 __be32 serial); 2166 void sctp_asconf_queue_teardown(struct sctp_association *asoc); 2167 2168 int sctp_cmp_addr_exact(const union sctp_addr *ss1, 2169 const union sctp_addr *ss2); 2170 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc); 2171 2172 /* A convenience structure to parse out SCTP specific CMSGs. */ 2173 struct sctp_cmsgs { 2174 struct sctp_initmsg *init; 2175 struct sctp_sndrcvinfo *srinfo; 2176 struct sctp_sndinfo *sinfo; 2177 struct sctp_prinfo *prinfo; 2178 struct sctp_authinfo *authinfo; 2179 struct msghdr *addrs_msg; 2180 }; 2181 2182 /* Structure for tracking memory objects */ 2183 struct sctp_dbg_objcnt_entry { 2184 char *label; 2185 atomic_t *counter; 2186 }; 2187 2188 #endif /* __sctp_structs_h__ */ 2189