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 <linux/ktime.h> 36 #include <linux/generic-radix-tree.h> 37 #include <linux/rhashtable-types.h> 38 #include <linux/socket.h> /* linux/in.h needs this!! */ 39 #include <linux/in.h> /* We get struct sockaddr_in. */ 40 #include <linux/in6.h> /* We get struct in6_addr */ 41 #include <linux/ipv6.h> 42 #include <asm/param.h> /* We get MAXHOSTNAMELEN. */ 43 #include <linux/atomic.h> /* This gets us atomic counters. */ 44 #include <linux/skbuff.h> /* We need sk_buff_head. */ 45 #include <linux/workqueue.h> /* We need tq_struct. */ 46 #include <linux/sctp.h> /* We need sctp* header structs. */ 47 #include <net/sctp/auth.h> /* We need auth specific structs */ 48 #include <net/ip.h> /* For inet_skb_parm */ 49 50 /* A convenience structure for handling sockaddr structures. 51 * We should wean ourselves off this. 52 */ 53 union sctp_addr { 54 struct sockaddr_in v4; 55 struct sockaddr_in6 v6; 56 struct sockaddr sa; 57 }; 58 59 /* Forward declarations for data structures. */ 60 struct sctp_globals; 61 struct sctp_endpoint; 62 struct sctp_association; 63 struct sctp_transport; 64 struct sctp_packet; 65 struct sctp_chunk; 66 struct sctp_inq; 67 struct sctp_outq; 68 struct sctp_bind_addr; 69 struct sctp_ulpq; 70 struct sctp_ep_common; 71 struct crypto_shash; 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 /* Access to HMAC transform. */ 159 struct crypto_shash *hmac; 160 char *sctp_hmac_alg; 161 162 /* What is our base endpointer? */ 163 struct sctp_endpoint *ep; 164 165 struct sctp_bind_bucket *bind_hash; 166 /* Various Socket Options. */ 167 __u16 default_stream; 168 __u32 default_ppid; 169 __u16 default_flags; 170 __u32 default_context; 171 __u32 default_timetolive; 172 __u32 default_rcv_context; 173 int max_burst; 174 175 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 176 * the destination address every heartbeat interval. This value 177 * will be inherited by all new associations. 178 */ 179 __u32 hbinterval; 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; 227 228 atomic_t pd_mode; 229 230 /* Fields after this point will be skipped on copies, like on accept 231 * and peeloff operations 232 */ 233 234 /* Receive to here while partial delivery is in effect. */ 235 struct sk_buff_head pd_lobby; 236 237 struct list_head auto_asconf_list; 238 int do_auto_asconf; 239 }; 240 241 static inline struct sctp_sock *sctp_sk(const struct sock *sk) 242 { 243 return (struct sctp_sock *)sk; 244 } 245 246 static inline struct sock *sctp_opt2sk(const struct sctp_sock *sp) 247 { 248 return (struct sock *)sp; 249 } 250 251 #if IS_ENABLED(CONFIG_IPV6) 252 struct sctp6_sock { 253 struct sctp_sock sctp; 254 struct ipv6_pinfo inet6; 255 }; 256 #endif /* CONFIG_IPV6 */ 257 258 259 /* This is our APPLICATION-SPECIFIC state cookie. 260 * THIS IS NOT DICTATED BY THE SPECIFICATION. 261 */ 262 /* These are the parts of an association which we send in the cookie. 263 * Most of these are straight out of: 264 * RFC2960 12.2 Parameters necessary per association (i.e. the TCB) 265 * 266 */ 267 268 struct sctp_cookie { 269 270 /* My : Tag expected in every inbound packet and sent 271 * Verification: in the INIT or INIT ACK chunk. 272 * Tag : 273 */ 274 __u32 my_vtag; 275 276 /* Peer's : Tag expected in every outbound packet except 277 * Verification: in the INIT chunk. 278 * Tag : 279 */ 280 __u32 peer_vtag; 281 282 /* The rest of these are not from the spec, but really need to 283 * be in the cookie. 284 */ 285 286 /* My Tie Tag : Assist in discovering a restarting association. */ 287 __u32 my_ttag; 288 289 /* Peer's Tie Tag: Assist in discovering a restarting association. */ 290 __u32 peer_ttag; 291 292 /* When does this cookie expire? */ 293 ktime_t expiration; 294 295 /* Number of inbound/outbound streams which are set 296 * and negotiated during the INIT process. 297 */ 298 __u16 sinit_num_ostreams; 299 __u16 sinit_max_instreams; 300 301 /* This is the first sequence number I used. */ 302 __u32 initial_tsn; 303 304 /* This holds the originating address of the INIT packet. */ 305 union sctp_addr peer_addr; 306 307 /* IG Section 2.35.3 308 * Include the source port of the INIT-ACK 309 */ 310 __u16 my_port; 311 312 __u8 prsctp_capable; 313 314 /* Padding for future use */ 315 __u8 padding; 316 317 __u32 adaptation_ind; 318 319 __u8 auth_random[sizeof(struct sctp_paramhdr) + 320 SCTP_AUTH_RANDOM_LENGTH]; 321 __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2]; 322 __u8 auth_chunks[sizeof(struct sctp_paramhdr) + SCTP_AUTH_MAX_CHUNKS]; 323 324 /* This is a shim for my peer's INIT packet, followed by 325 * a copy of the raw address list of the association. 326 * The length of the raw address list is saved in the 327 * raw_addr_list_len field, which will be used at the time when 328 * the association TCB is re-constructed from the cookie. 329 */ 330 __u32 raw_addr_list_len; 331 struct sctp_init_chunk peer_init[]; 332 }; 333 334 335 /* The format of our cookie that we send to our peer. */ 336 struct sctp_signed_cookie { 337 __u8 signature[SCTP_SECRET_SIZE]; 338 __u32 __pad; /* force sctp_cookie alignment to 64 bits */ 339 struct sctp_cookie c; 340 } __packed; 341 342 /* This is another convenience type to allocate memory for address 343 * params for the maximum size and pass such structures around 344 * internally. 345 */ 346 union sctp_addr_param { 347 struct sctp_paramhdr p; 348 struct sctp_ipv4addr_param v4; 349 struct sctp_ipv6addr_param v6; 350 }; 351 352 /* A convenience type to allow walking through the various 353 * parameters and avoid casting all over the place. 354 */ 355 union sctp_params { 356 void *v; 357 struct sctp_paramhdr *p; 358 struct sctp_cookie_preserve_param *life; 359 struct sctp_hostname_param *dns; 360 struct sctp_cookie_param *cookie; 361 struct sctp_supported_addrs_param *sat; 362 struct sctp_ipv4addr_param *v4; 363 struct sctp_ipv6addr_param *v6; 364 union sctp_addr_param *addr; 365 struct sctp_adaptation_ind_param *aind; 366 struct sctp_supported_ext_param *ext; 367 struct sctp_random_param *random; 368 struct sctp_chunks_param *chunks; 369 struct sctp_hmac_algo_param *hmac_algo; 370 struct sctp_addip_param *addip; 371 }; 372 373 /* RFC 2960. Section 3.3.5 Heartbeat. 374 * Heartbeat Information: variable length 375 * The Sender-specific Heartbeat Info field should normally include 376 * information about the sender's current time when this HEARTBEAT 377 * chunk is sent and the destination transport address to which this 378 * HEARTBEAT is sent (see Section 8.3). 379 */ 380 struct sctp_sender_hb_info { 381 struct sctp_paramhdr param_hdr; 382 union sctp_addr daddr; 383 unsigned long sent_at; 384 __u64 hb_nonce; 385 }; 386 387 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt, 388 gfp_t gfp); 389 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid); 390 void sctp_stream_free(struct sctp_stream *stream); 391 void sctp_stream_clear(struct sctp_stream *stream); 392 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new); 393 394 /* What is the current SSN number for this stream? */ 395 #define sctp_ssn_peek(stream, type, sid) \ 396 (sctp_stream_##type((stream), (sid))->ssn) 397 398 /* Return the next SSN number for this stream. */ 399 #define sctp_ssn_next(stream, type, sid) \ 400 (sctp_stream_##type((stream), (sid))->ssn++) 401 402 /* Skip over this ssn and all below. */ 403 #define sctp_ssn_skip(stream, type, sid, ssn) \ 404 (sctp_stream_##type((stream), (sid))->ssn = ssn + 1) 405 406 /* What is the current MID number for this stream? */ 407 #define sctp_mid_peek(stream, type, sid) \ 408 (sctp_stream_##type((stream), (sid))->mid) 409 410 /* Return the next MID number for this stream. */ 411 #define sctp_mid_next(stream, type, sid) \ 412 (sctp_stream_##type((stream), (sid))->mid++) 413 414 /* Skip over this mid and all below. */ 415 #define sctp_mid_skip(stream, type, sid, mid) \ 416 (sctp_stream_##type((stream), (sid))->mid = mid + 1) 417 418 /* What is the current MID_uo number for this stream? */ 419 #define sctp_mid_uo_peek(stream, type, sid) \ 420 (sctp_stream_##type((stream), (sid))->mid_uo) 421 422 /* Return the next MID_uo number for this stream. */ 423 #define sctp_mid_uo_next(stream, type, sid) \ 424 (sctp_stream_##type((stream), (sid))->mid_uo++) 425 426 /* 427 * Pointers to address related SCTP functions. 428 * (i.e. things that depend on the address family.) 429 */ 430 struct sctp_af { 431 int (*sctp_xmit) (struct sk_buff *skb, 432 struct sctp_transport *); 433 int (*setsockopt) (struct sock *sk, 434 int level, 435 int optname, 436 sockptr_t optval, 437 unsigned int optlen); 438 int (*getsockopt) (struct sock *sk, 439 int level, 440 int optname, 441 char __user *optval, 442 int __user *optlen); 443 void (*get_dst) (struct sctp_transport *t, 444 union sctp_addr *saddr, 445 struct flowi *fl, 446 struct sock *sk); 447 void (*get_saddr) (struct sctp_sock *sk, 448 struct sctp_transport *t, 449 struct flowi *fl); 450 void (*copy_addrlist) (struct list_head *, 451 struct net_device *); 452 int (*cmp_addr) (const union sctp_addr *addr1, 453 const union sctp_addr *addr2); 454 void (*addr_copy) (union sctp_addr *dst, 455 union sctp_addr *src); 456 void (*from_skb) (union sctp_addr *, 457 struct sk_buff *skb, 458 int saddr); 459 void (*from_sk) (union sctp_addr *, 460 struct sock *sk); 461 void (*from_addr_param) (union sctp_addr *, 462 union sctp_addr_param *, 463 __be16 port, int iif); 464 int (*to_addr_param) (const union sctp_addr *, 465 union sctp_addr_param *); 466 int (*addr_valid) (union sctp_addr *, 467 struct sctp_sock *, 468 const struct sk_buff *); 469 enum sctp_scope (*scope)(union sctp_addr *); 470 void (*inaddr_any) (union sctp_addr *, __be16); 471 int (*is_any) (const union sctp_addr *); 472 int (*available) (union sctp_addr *, 473 struct sctp_sock *); 474 int (*skb_iif) (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 messenge 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 tsn_missing_report:2, /* Data chunk missing counter. */ 657 fast_retransmit:2; /* Is this chunk fast retransmitted? */ 658 }; 659 660 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1) 661 void sctp_chunk_hold(struct sctp_chunk *); 662 void sctp_chunk_put(struct sctp_chunk *); 663 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len, 664 struct iov_iter *from); 665 void sctp_chunk_free(struct sctp_chunk *); 666 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data); 667 struct sctp_chunk *sctp_chunkify(struct sk_buff *, 668 const struct sctp_association *, 669 struct sock *, gfp_t gfp); 670 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *, 671 union sctp_addr *); 672 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk); 673 674 static inline __u16 sctp_chunk_stream_no(struct sctp_chunk *ch) 675 { 676 return ntohs(ch->subh.data_hdr->stream); 677 } 678 679 enum { 680 SCTP_ADDR_NEW, /* new address added to assoc/ep */ 681 SCTP_ADDR_SRC, /* address can be used as source */ 682 SCTP_ADDR_DEL, /* address about to be deleted */ 683 }; 684 685 /* This is a structure for holding either an IPv6 or an IPv4 address. */ 686 struct sctp_sockaddr_entry { 687 struct list_head list; 688 struct rcu_head rcu; 689 union sctp_addr a; 690 __u8 state; 691 __u8 valid; 692 }; 693 694 #define SCTP_ADDRESS_TICK_DELAY 500 695 696 /* This structure holds lists of chunks as we are assembling for 697 * transmission. 698 */ 699 struct sctp_packet { 700 /* These are the SCTP header values (host order) for the packet. */ 701 __u16 source_port; 702 __u16 destination_port; 703 __u32 vtag; 704 705 /* This contains the payload chunks. */ 706 struct list_head chunk_list; 707 708 /* This is the overhead of the sctp and ip headers. */ 709 size_t overhead; 710 /* This is the total size of all chunks INCLUDING padding. */ 711 size_t size; 712 /* This is the maximum size this packet may have */ 713 size_t max_size; 714 715 /* The packet is destined for this transport address. 716 * The function we finally use to pass down to the next lower 717 * layer lives in the transport structure. 718 */ 719 struct sctp_transport *transport; 720 721 /* pointer to the auth chunk for this packet */ 722 struct sctp_chunk *auth; 723 724 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */ 725 has_sack:1, /* This packet contains a SACK chunk. */ 726 has_auth:1, /* This packet contains an AUTH chunk */ 727 has_data:1, /* This packet contains at least 1 DATA chunk */ 728 ipfragok:1; /* So let ip fragment this packet */ 729 }; 730 731 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *, 732 __u16 sport, __u16 dport); 733 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int); 734 enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet, 735 struct sctp_chunk *chunk, 736 int one_packet, gfp_t gfp); 737 enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet, 738 struct sctp_chunk *chunk); 739 int sctp_packet_transmit(struct sctp_packet *, gfp_t); 740 void sctp_packet_free(struct sctp_packet *); 741 742 static inline int sctp_packet_empty(struct sctp_packet *packet) 743 { 744 return packet->size == packet->overhead; 745 } 746 747 /* This represents a remote transport address. 748 * For local transport addresses, we just use union sctp_addr. 749 * 750 * RFC2960 Section 1.4 Key Terms 751 * 752 * o Transport address: A Transport Address is traditionally defined 753 * by Network Layer address, Transport Layer protocol and Transport 754 * Layer port number. In the case of SCTP running over IP, a 755 * transport address is defined by the combination of an IP address 756 * and an SCTP port number (where SCTP is the Transport protocol). 757 * 758 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control 759 * 760 * o The sender keeps a separate congestion control parameter set for 761 * each of the destination addresses it can send to (not each 762 * source-destination pair but for each destination). The parameters 763 * should decay if the address is not used for a long enough time 764 * period. 765 * 766 */ 767 struct sctp_transport { 768 /* A list of transports. */ 769 struct list_head transports; 770 struct rhlist_head node; 771 772 /* Reference counting. */ 773 refcount_t refcnt; 774 /* RTO-Pending : A flag used to track if one of the DATA 775 * chunks sent to this address is currently being 776 * used to compute a RTT. If this flag is 0, 777 * the next DATA chunk sent to this destination 778 * should be used to compute a RTT and this flag 779 * should be set. Every time the RTT 780 * calculation completes (i.e. the DATA chunk 781 * is SACK'd) clear this flag. 782 */ 783 __u32 rto_pending:1, 784 785 /* 786 * hb_sent : a flag that signals that we have a pending 787 * heartbeat. 788 */ 789 hb_sent:1, 790 791 /* Is the Path MTU update pending on this tranport */ 792 pmtu_pending:1, 793 794 dst_pending_confirm:1, /* need to confirm neighbour */ 795 796 /* Has this transport moved the ctsn since we last sacked */ 797 sack_generation:1; 798 u32 dst_cookie; 799 800 struct flowi fl; 801 802 /* This is the peer's IP address and port. */ 803 union sctp_addr ipaddr; 804 805 /* These are the functions we call to handle LLP stuff. */ 806 struct sctp_af *af_specific; 807 808 /* Which association do we belong to? */ 809 struct sctp_association *asoc; 810 811 /* RFC2960 812 * 813 * 12.3 Per Transport Address Data 814 * 815 * For each destination transport address in the peer's 816 * address list derived from the INIT or INIT ACK chunk, a 817 * number of data elements needs to be maintained including: 818 */ 819 /* RTO : The current retransmission timeout value. */ 820 unsigned long rto; 821 822 __u32 rtt; /* This is the most recent RTT. */ 823 824 /* RTTVAR : The current RTT variation. */ 825 __u32 rttvar; 826 827 /* SRTT : The current smoothed round trip time. */ 828 __u32 srtt; 829 830 /* 831 * These are the congestion stats. 832 */ 833 /* cwnd : The current congestion window. */ 834 __u32 cwnd; /* This is the actual cwnd. */ 835 836 /* ssthresh : The current slow start threshold value. */ 837 __u32 ssthresh; 838 839 /* partial : The tracking method for increase of cwnd when in 840 * bytes acked : congestion avoidance mode (see Section 6.2.2) 841 */ 842 __u32 partial_bytes_acked; 843 844 /* Data that has been sent, but not acknowledged. */ 845 __u32 flight_size; 846 847 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */ 848 849 /* Destination */ 850 struct dst_entry *dst; 851 /* Source address. */ 852 union sctp_addr saddr; 853 854 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 855 * the destination address every heartbeat interval. 856 */ 857 unsigned long hbinterval; 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 /* This is the max_retrans value for the transport and will 881 * be initialized from the assocs value. This can be changed 882 * using the SCTP_SET_PEER_ADDR_PARAMS socket option. 883 */ 884 __u16 pathmaxrxt; 885 886 __u32 flowlabel; 887 __u8 dscp; 888 889 /* This is the partially failed retrans value for the transport 890 * and will be initialized from the assocs value. This can be changed 891 * using the SCTP_PEER_ADDR_THLDS socket option 892 */ 893 __u16 pf_retrans; 894 /* Used for primary path switchover. */ 895 __u16 ps_retrans; 896 /* PMTU : The current known path MTU. */ 897 __u32 pathmtu; 898 899 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 900 __u32 param_flags; 901 902 /* The number of times INIT has been sent on this transport. */ 903 int init_sent_count; 904 905 /* state : The current state of this destination, 906 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN. 907 */ 908 int state; 909 910 /* These are the error stats for this destination. */ 911 912 /* Error count : The current error count for this destination. */ 913 unsigned short error_count; 914 915 /* Per : A timer used by each destination. 916 * Destination : 917 * Timer : 918 * 919 * [Everywhere else in the text this is called T3-rtx. -ed] 920 */ 921 struct timer_list T3_rtx_timer; 922 923 /* Heartbeat timer is per destination. */ 924 struct timer_list hb_timer; 925 926 /* Timer to handle ICMP proto unreachable envets */ 927 struct timer_list proto_unreach_timer; 928 929 /* Timer to handler reconf chunk rtx */ 930 struct timer_list reconf_timer; 931 932 /* Since we're using per-destination retransmission timers 933 * (see above), we're also using per-destination "transmitted" 934 * queues. This probably ought to be a private struct 935 * accessible only within the outqueue, but it's not, yet. 936 */ 937 struct list_head transmitted; 938 939 /* We build bundle-able packets for this transport here. */ 940 struct sctp_packet packet; 941 942 /* This is the list of transports that have chunks to send. */ 943 struct list_head send_ready; 944 945 /* State information saved for SFR_CACC algorithm. The key 946 * idea in SFR_CACC is to maintain state at the sender on a 947 * per-destination basis when a changeover happens. 948 * char changeover_active; 949 * char cycling_changeover; 950 * __u32 next_tsn_at_change; 951 * char cacc_saw_newack; 952 */ 953 struct { 954 /* An unsigned integer, which stores the next TSN to be 955 * used by the sender, at the moment of changeover. 956 */ 957 __u32 next_tsn_at_change; 958 959 /* A flag which indicates the occurrence of a changeover */ 960 char changeover_active; 961 962 /* A flag which indicates whether the change of primary is 963 * the first switch to this destination address during an 964 * active switch. 965 */ 966 char cycling_changeover; 967 968 /* A temporary flag, which is used during the processing of 969 * a SACK to estimate the causative TSN(s)'s group. 970 */ 971 char cacc_saw_newack; 972 } cacc; 973 974 /* 64-bit random number sent with heartbeat. */ 975 __u64 hb_nonce; 976 977 struct rcu_head rcu; 978 }; 979 980 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *, 981 gfp_t); 982 void sctp_transport_set_owner(struct sctp_transport *, 983 struct sctp_association *); 984 void sctp_transport_route(struct sctp_transport *, union sctp_addr *, 985 struct sctp_sock *); 986 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk); 987 void sctp_transport_free(struct sctp_transport *); 988 void sctp_transport_reset_t3_rtx(struct sctp_transport *); 989 void sctp_transport_reset_hb_timer(struct sctp_transport *); 990 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport); 991 int sctp_transport_hold(struct sctp_transport *); 992 void sctp_transport_put(struct sctp_transport *); 993 void sctp_transport_update_rto(struct sctp_transport *, __u32); 994 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32); 995 void sctp_transport_lower_cwnd(struct sctp_transport *t, 996 enum sctp_lower_cwnd reason); 997 void sctp_transport_burst_limited(struct sctp_transport *); 998 void sctp_transport_burst_reset(struct sctp_transport *); 999 unsigned long sctp_transport_timeout(struct sctp_transport *); 1000 void sctp_transport_reset(struct sctp_transport *t); 1001 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu); 1002 void sctp_transport_immediate_rtx(struct sctp_transport *); 1003 void sctp_transport_dst_release(struct sctp_transport *t); 1004 void sctp_transport_dst_confirm(struct sctp_transport *t); 1005 1006 1007 /* This is the structure we use to queue packets as they come into 1008 * SCTP. We write packets to it and read chunks from it. 1009 */ 1010 struct sctp_inq { 1011 /* This is actually a queue of sctp_chunk each 1012 * containing a partially decoded packet. 1013 */ 1014 struct list_head in_chunk_list; 1015 /* This is the packet which is currently off the in queue and is 1016 * being worked on through the inbound chunk processing. 1017 */ 1018 struct sctp_chunk *in_progress; 1019 1020 /* This is the delayed task to finish delivering inbound 1021 * messages. 1022 */ 1023 struct work_struct immediate; 1024 }; 1025 1026 void sctp_inq_init(struct sctp_inq *); 1027 void sctp_inq_free(struct sctp_inq *); 1028 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet); 1029 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *); 1030 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *); 1031 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t); 1032 1033 /* This is the structure we use to hold outbound chunks. You push 1034 * chunks in and they automatically pop out the other end as bundled 1035 * packets (it calls (*output_handler)()). 1036 * 1037 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1, 1038 * and 8.2 of the v13 draft. 1039 * 1040 * It handles retransmissions. The connection to the timeout portion 1041 * of the state machine is through sctp_..._timeout() and timeout_handler. 1042 * 1043 * If you feed it SACKs, it will eat them. 1044 * 1045 * If you give it big chunks, it will fragment them. 1046 * 1047 * It assigns TSN's to data chunks. This happens at the last possible 1048 * instant before transmission. 1049 * 1050 * When free()'d, it empties itself out via output_handler(). 1051 */ 1052 struct sctp_outq { 1053 struct sctp_association *asoc; 1054 1055 /* Data pending that has never been transmitted. */ 1056 struct list_head out_chunk_list; 1057 1058 /* Stream scheduler being used */ 1059 struct sctp_sched_ops *sched; 1060 1061 unsigned int out_qlen; /* Total length of queued data chunks. */ 1062 1063 /* Error of send failed, may used in SCTP_SEND_FAILED event. */ 1064 unsigned int error; 1065 1066 /* These are control chunks we want to send. */ 1067 struct list_head control_chunk_list; 1068 1069 /* These are chunks that have been sacked but are above the 1070 * CTSN, or cumulative tsn ack point. 1071 */ 1072 struct list_head sacked; 1073 1074 /* Put chunks on this list to schedule them for 1075 * retransmission. 1076 */ 1077 struct list_head retransmit; 1078 1079 /* Put chunks on this list to save them for FWD TSN processing as 1080 * they were abandoned. 1081 */ 1082 struct list_head abandoned; 1083 1084 /* How many unackd bytes do we have in-flight? */ 1085 __u32 outstanding_bytes; 1086 1087 /* Are we doing fast-rtx on this queue */ 1088 char fast_rtx; 1089 1090 /* Corked? */ 1091 char cork; 1092 }; 1093 1094 void sctp_outq_init(struct sctp_association *, struct sctp_outq *); 1095 void sctp_outq_teardown(struct sctp_outq *); 1096 void sctp_outq_free(struct sctp_outq*); 1097 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t); 1098 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *); 1099 int sctp_outq_is_empty(const struct sctp_outq *); 1100 void sctp_outq_restart(struct sctp_outq *); 1101 1102 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport, 1103 enum sctp_retransmit_reason reason); 1104 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8); 1105 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp); 1106 void sctp_prsctp_prune(struct sctp_association *asoc, 1107 struct sctp_sndrcvinfo *sinfo, int msg_len); 1108 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn); 1109 /* Uncork and flush an outqueue. */ 1110 static inline void sctp_outq_cork(struct sctp_outq *q) 1111 { 1112 q->cork = 1; 1113 } 1114 1115 /* SCTP skb control block. 1116 * sctp_input_cb is currently used on rx and sock rx queue 1117 */ 1118 struct sctp_input_cb { 1119 union { 1120 struct inet_skb_parm h4; 1121 #if IS_ENABLED(CONFIG_IPV6) 1122 struct inet6_skb_parm h6; 1123 #endif 1124 } header; 1125 struct sctp_chunk *chunk; 1126 struct sctp_af *af; 1127 }; 1128 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0])) 1129 1130 struct sctp_output_cb { 1131 struct sk_buff *last; 1132 }; 1133 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0])) 1134 1135 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb) 1136 { 1137 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; 1138 1139 return chunk->head_skb ? : skb; 1140 } 1141 1142 /* These bind address data fields common between endpoints and associations */ 1143 struct sctp_bind_addr { 1144 1145 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1146 * 1147 * SCTP Port: The local SCTP port number the endpoint is 1148 * bound to. 1149 */ 1150 __u16 port; 1151 1152 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1153 * 1154 * Address List: The list of IP addresses that this instance 1155 * has bound. This information is passed to one's 1156 * peer(s) in INIT and INIT ACK chunks. 1157 */ 1158 struct list_head address_list; 1159 }; 1160 1161 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port); 1162 void sctp_bind_addr_free(struct sctp_bind_addr *); 1163 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest, 1164 const struct sctp_bind_addr *src, 1165 enum sctp_scope scope, gfp_t gfp, 1166 int flags); 1167 int sctp_bind_addr_dup(struct sctp_bind_addr *dest, 1168 const struct sctp_bind_addr *src, 1169 gfp_t gfp); 1170 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *, 1171 int new_size, __u8 addr_state, gfp_t gfp); 1172 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *); 1173 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *, 1174 struct sctp_sock *); 1175 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *, 1176 struct sctp_sock *, struct sctp_sock *); 1177 int sctp_bind_addr_state(const struct sctp_bind_addr *bp, 1178 const union sctp_addr *addr); 1179 int sctp_bind_addrs_check(struct sctp_sock *sp, 1180 struct sctp_sock *sp2, int cnt2); 1181 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp, 1182 const union sctp_addr *addrs, 1183 int addrcnt, 1184 struct sctp_sock *opt); 1185 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp, 1186 int *addrs_len, 1187 gfp_t gfp); 1188 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len, 1189 __u16 port, gfp_t gfp); 1190 1191 enum sctp_scope sctp_scope(const union sctp_addr *addr); 1192 int sctp_in_scope(struct net *net, const union sctp_addr *addr, 1193 const enum sctp_scope scope); 1194 int sctp_is_any(struct sock *sk, const union sctp_addr *addr); 1195 int sctp_is_ep_boundall(struct sock *sk); 1196 1197 1198 /* What type of endpoint? */ 1199 enum sctp_endpoint_type { 1200 SCTP_EP_TYPE_SOCKET, 1201 SCTP_EP_TYPE_ASSOCIATION, 1202 }; 1203 1204 /* 1205 * A common base class to bridge the implmentation view of a 1206 * socket (usually listening) endpoint versus an association's 1207 * local endpoint. 1208 * This common structure is useful for several purposes: 1209 * 1) Common interface for lookup routines. 1210 * a) Subfunctions work for either endpoint or association 1211 * b) Single interface to lookup allows hiding the lookup lock rather 1212 * than acquiring it externally. 1213 * 2) Common interface for the inbound chunk handling/state machine. 1214 * 3) Common object handling routines for reference counting, etc. 1215 * 4) Disentangle association lookup from endpoint lookup, where we 1216 * do not have to find our endpoint to find our association. 1217 * 1218 */ 1219 1220 struct sctp_ep_common { 1221 /* Fields to help us manage our entries in the hash tables. */ 1222 struct hlist_node node; 1223 int hashent; 1224 1225 /* Runtime type information. What kind of endpoint is this? */ 1226 enum sctp_endpoint_type type; 1227 1228 /* Some fields to help us manage this object. 1229 * refcnt - Reference count access to this object. 1230 * dead - Do not attempt to use this object. 1231 */ 1232 refcount_t refcnt; 1233 bool dead; 1234 1235 /* What socket does this endpoint belong to? */ 1236 struct sock *sk; 1237 1238 /* Cache netns and it won't change once set */ 1239 struct net *net; 1240 1241 /* This is where we receive inbound chunks. */ 1242 struct sctp_inq inqueue; 1243 1244 /* This substructure includes the defining parameters of the 1245 * endpoint: 1246 * bind_addr.port is our shared port number. 1247 * bind_addr.address_list is our set of local IP addresses. 1248 */ 1249 struct sctp_bind_addr bind_addr; 1250 }; 1251 1252 1253 /* RFC Section 1.4 Key Terms 1254 * 1255 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a 1256 * multi-homed host, an SCTP endpoint is represented to its peers as a 1257 * combination of a set of eligible destination transport addresses to 1258 * which SCTP packets can be sent and a set of eligible source 1259 * transport addresses from which SCTP packets can be received. 1260 * All transport addresses used by an SCTP endpoint must use the 1261 * same port number, but can use multiple IP addresses. A transport 1262 * address used by an SCTP endpoint must not be used by another 1263 * SCTP endpoint. In other words, a transport address is unique 1264 * to an SCTP endpoint. 1265 * 1266 * From an implementation perspective, each socket has one of these. 1267 * A TCP-style socket will have exactly one association on one of 1268 * these. An UDP-style socket will have multiple associations hanging 1269 * off one of these. 1270 */ 1271 1272 struct sctp_endpoint { 1273 /* Common substructure for endpoint and association. */ 1274 struct sctp_ep_common base; 1275 1276 /* Associations: A list of current associations and mappings 1277 * to the data consumers for each association. This 1278 * may be in the form of a hash table or other 1279 * implementation dependent structure. The data 1280 * consumers may be process identification 1281 * information such as file descriptors, named pipe 1282 * pointer, or table pointers dependent on how SCTP 1283 * is implemented. 1284 */ 1285 /* This is really a list of struct sctp_association entries. */ 1286 struct list_head asocs; 1287 1288 /* Secret Key: A secret key used by this endpoint to compute 1289 * the MAC. This SHOULD be a cryptographic quality 1290 * random number with a sufficient length. 1291 * Discussion in [RFC1750] can be helpful in 1292 * selection of the key. 1293 */ 1294 __u8 secret_key[SCTP_SECRET_SIZE]; 1295 1296 /* digest: This is a digest of the sctp cookie. This field is 1297 * only used on the receive path when we try to validate 1298 * that the cookie has not been tampered with. We put 1299 * this here so we pre-allocate this once and can re-use 1300 * on every receive. 1301 */ 1302 __u8 *digest; 1303 1304 /* sendbuf acct. policy. */ 1305 __u32 sndbuf_policy; 1306 1307 /* rcvbuf acct. policy. */ 1308 __u32 rcvbuf_policy; 1309 1310 /* SCTP AUTH: array of the HMACs that will be allocated 1311 * we need this per association so that we don't serialize 1312 */ 1313 struct crypto_shash **auth_hmacs; 1314 1315 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */ 1316 struct sctp_hmac_algo_param *auth_hmacs_list; 1317 1318 /* SCTP-AUTH: chunks to authenticate encoded into parameter */ 1319 struct sctp_chunks_param *auth_chunk_list; 1320 1321 /* SCTP-AUTH: endpoint shared keys */ 1322 struct list_head endpoint_shared_keys; 1323 __u16 active_key_id; 1324 __u8 ecn_enable:1, 1325 auth_enable:1, 1326 intl_enable:1, 1327 prsctp_enable:1, 1328 asconf_enable:1, 1329 reconf_enable:1; 1330 1331 __u8 strreset_enable; 1332 1333 /* Security identifiers from incoming (INIT). These are set by 1334 * security_sctp_assoc_request(). These will only be used by 1335 * SCTP TCP type sockets and peeled off connections as they 1336 * cause a new socket to be generated. security_sctp_sk_clone() 1337 * will then plug these into the new socket. 1338 */ 1339 1340 u32 secid; 1341 u32 peer_secid; 1342 }; 1343 1344 /* Recover the outter endpoint structure. */ 1345 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base) 1346 { 1347 struct sctp_endpoint *ep; 1348 1349 ep = container_of(base, struct sctp_endpoint, base); 1350 return ep; 1351 } 1352 1353 /* These are function signatures for manipulating endpoints. */ 1354 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t); 1355 void sctp_endpoint_free(struct sctp_endpoint *); 1356 void sctp_endpoint_put(struct sctp_endpoint *); 1357 void sctp_endpoint_hold(struct sctp_endpoint *); 1358 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *); 1359 struct sctp_association *sctp_endpoint_lookup_assoc( 1360 const struct sctp_endpoint *ep, 1361 const union sctp_addr *paddr, 1362 struct sctp_transport **); 1363 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep, 1364 const union sctp_addr *paddr); 1365 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *, 1366 struct net *, const union sctp_addr *); 1367 bool sctp_has_association(struct net *net, const union sctp_addr *laddr, 1368 const union sctp_addr *paddr); 1369 1370 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep, 1371 const struct sctp_association *asoc, 1372 enum sctp_cid cid, struct sctp_init_chunk *peer_init, 1373 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk); 1374 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk, 1375 const union sctp_addr *peer, 1376 struct sctp_init_chunk *init, gfp_t gfp); 1377 __u32 sctp_generate_tag(const struct sctp_endpoint *); 1378 __u32 sctp_generate_tsn(const struct sctp_endpoint *); 1379 1380 struct sctp_inithdr_host { 1381 __u32 init_tag; 1382 __u32 a_rwnd; 1383 __u16 num_outbound_streams; 1384 __u16 num_inbound_streams; 1385 __u32 initial_tsn; 1386 }; 1387 1388 struct sctp_stream_priorities { 1389 /* List of priorities scheduled */ 1390 struct list_head prio_sched; 1391 /* List of streams scheduled */ 1392 struct list_head active; 1393 /* The next stream in line */ 1394 struct sctp_stream_out_ext *next; 1395 __u16 prio; 1396 }; 1397 1398 struct sctp_stream_out_ext { 1399 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 1400 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 1401 struct list_head outq; /* chunks enqueued by this stream */ 1402 union { 1403 struct { 1404 /* Scheduled streams list */ 1405 struct list_head prio_list; 1406 struct sctp_stream_priorities *prio_head; 1407 }; 1408 /* Fields used by RR scheduler */ 1409 struct { 1410 struct list_head rr_list; 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 }; 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 hostname_address:1, /* Peer understands DNS addresses? */ 1687 asconf_capable:1, /* Does peer support ADDIP? */ 1688 prsctp_capable:1, /* Can peer do PR-SCTP? */ 1689 reconf_capable:1, /* Can peer do RE-CONFIG? */ 1690 intl_capable:1, /* Can peer do INTERLEAVE */ 1691 auth_capable:1, /* Is peer doing SCTP-AUTH? */ 1692 /* sack_needed: 1693 * This flag indicates if the next received 1694 * packet is to be responded to with a 1695 * SACK. This is initialized to 0. When a packet 1696 * is received sack_cnt is incremented. If this value 1697 * reaches 2 or more, a SACK is sent and the 1698 * value is reset to 0. Note: This is used only 1699 * when no DATA chunks are received out of 1700 * order. When DATA chunks are out of order, 1701 * SACK's are not delayed (see Section 6). 1702 */ 1703 sack_needed:1, /* Do we need to sack the peer? */ 1704 sack_generation:1, 1705 zero_window_announced:1; 1706 1707 __u32 sack_cnt; 1708 1709 __u32 adaptation_ind; /* Adaptation Code point. */ 1710 1711 struct sctp_inithdr_host i; 1712 void *cookie; 1713 int cookie_len; 1714 1715 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. 1716 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the 1717 * Initial TSN Value minus 1 1718 */ 1719 __u32 addip_serial; 1720 1721 /* SCTP-AUTH: We need to know pears random number, hmac list 1722 * and authenticated chunk list. All that is part of the 1723 * cookie and these are just pointers to those locations 1724 */ 1725 struct sctp_random_param *peer_random; 1726 struct sctp_chunks_param *peer_chunks; 1727 struct sctp_hmac_algo_param *peer_hmacs; 1728 } peer; 1729 1730 /* State : A state variable indicating what state the 1731 * : association is in, i.e. COOKIE-WAIT, 1732 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING, 1733 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT. 1734 * 1735 * Note: No "CLOSED" state is illustrated since if a 1736 * association is "CLOSED" its TCB SHOULD be removed. 1737 * 1738 * In this implementation we DO have a CLOSED 1739 * state which is used during initiation and shutdown. 1740 * 1741 * State takes values from SCTP_STATE_*. 1742 */ 1743 enum sctp_state state; 1744 1745 /* Overall : The overall association error count. 1746 * Error Count : [Clear this any time I get something.] 1747 */ 1748 int overall_error_count; 1749 1750 /* The cookie life I award for any cookie. */ 1751 ktime_t cookie_life; 1752 1753 /* These are the association's initial, max, and min RTO values. 1754 * These values will be initialized by system defaults, but can 1755 * be modified via the SCTP_RTOINFO socket option. 1756 */ 1757 unsigned long rto_initial; 1758 unsigned long rto_max; 1759 unsigned long rto_min; 1760 1761 /* Maximum number of new data packets that can be sent in a burst. */ 1762 int max_burst; 1763 1764 /* This is the max_retrans value for the association. This value will 1765 * be initialized from system defaults, but can be 1766 * modified by the SCTP_ASSOCINFO socket option. 1767 */ 1768 int max_retrans; 1769 1770 /* This is the partially failed retrans value for the transport 1771 * and will be initialized from the assocs value. This can be 1772 * changed using the SCTP_PEER_ADDR_THLDS socket option 1773 */ 1774 __u16 pf_retrans; 1775 /* Used for primary path switchover. */ 1776 __u16 ps_retrans; 1777 1778 /* Maximum number of times the endpoint will retransmit INIT */ 1779 __u16 max_init_attempts; 1780 1781 /* How many times have we resent an INIT? */ 1782 __u16 init_retries; 1783 1784 /* The largest timeout or RTO value to use in attempting an INIT */ 1785 unsigned long max_init_timeo; 1786 1787 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 1788 * the destination address every heartbeat interval. This value 1789 * will be inherited by all new transports. 1790 */ 1791 unsigned long hbinterval; 1792 1793 /* This is the max_retrans value for new transports in the 1794 * association. 1795 */ 1796 __u16 pathmaxrxt; 1797 1798 __u32 flowlabel; 1799 __u8 dscp; 1800 1801 /* Flag that path mtu update is pending */ 1802 __u8 pmtu_pending; 1803 1804 /* Association : The smallest PMTU discovered for all of the 1805 * PMTU : peer's transport addresses. 1806 */ 1807 __u32 pathmtu; 1808 1809 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 1810 __u32 param_flags; 1811 1812 __u32 sackfreq; 1813 /* SACK delay timeout */ 1814 unsigned long sackdelay; 1815 1816 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES]; 1817 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES]; 1818 1819 /* Transport to which SHUTDOWN chunk was last sent. */ 1820 struct sctp_transport *shutdown_last_sent_to; 1821 1822 /* Transport to which INIT chunk was last sent. */ 1823 struct sctp_transport *init_last_sent_to; 1824 1825 /* How many times have we resent a SHUTDOWN */ 1826 int shutdown_retries; 1827 1828 /* Next TSN : The next TSN number to be assigned to a new 1829 * : DATA chunk. This is sent in the INIT or INIT 1830 * : ACK chunk to the peer and incremented each 1831 * : time a DATA chunk is assigned a TSN 1832 * : (normally just prior to transmit or during 1833 * : fragmentation). 1834 */ 1835 __u32 next_tsn; 1836 1837 /* 1838 * Last Rcvd : This is the last TSN received in sequence. This value 1839 * TSN : is set initially by taking the peer's Initial TSN, 1840 * : received in the INIT or INIT ACK chunk, and 1841 * : subtracting one from it. 1842 * 1843 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point. 1844 */ 1845 1846 __u32 ctsn_ack_point; 1847 1848 /* PR-SCTP Advanced.Peer.Ack.Point */ 1849 __u32 adv_peer_ack_point; 1850 1851 /* Highest TSN that is acknowledged by incoming SACKs. */ 1852 __u32 highest_sacked; 1853 1854 /* TSN marking the fast recovery exit point */ 1855 __u32 fast_recovery_exit; 1856 1857 /* Flag to track the current fast recovery state */ 1858 __u8 fast_recovery; 1859 1860 /* The number of unacknowledged data chunks. Reported through 1861 * the SCTP_STATUS sockopt. 1862 */ 1863 __u16 unack_data; 1864 1865 /* The total number of data chunks that we've had to retransmit 1866 * as the result of a T3 timer expiration 1867 */ 1868 __u32 rtx_data_chunks; 1869 1870 /* This is the association's receive buffer space. This value is used 1871 * to set a_rwnd field in an INIT or a SACK chunk. 1872 */ 1873 __u32 rwnd; 1874 1875 /* This is the last advertised value of rwnd over a SACK chunk. */ 1876 __u32 a_rwnd; 1877 1878 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed 1879 * to slop over a maximum of the association's frag_point. 1880 */ 1881 __u32 rwnd_over; 1882 1883 /* Keeps treack of rwnd pressure. This happens when we have 1884 * a window, but not recevie buffer (i.e small packets). This one 1885 * is releases slowly (1 PMTU at a time ). 1886 */ 1887 __u32 rwnd_press; 1888 1889 /* This is the sndbuf size in use for the association. 1890 * This corresponds to the sndbuf size for the association, 1891 * as specified in the sk->sndbuf. 1892 */ 1893 int sndbuf_used; 1894 1895 /* This is the amount of memory that this association has allocated 1896 * in the receive path at any given time. 1897 */ 1898 atomic_t rmem_alloc; 1899 1900 /* This is the wait queue head for send requests waiting on 1901 * the association sndbuf space. 1902 */ 1903 wait_queue_head_t wait; 1904 1905 /* The message size at which SCTP fragmentation will occur. */ 1906 __u32 frag_point; 1907 __u32 user_frag; 1908 1909 /* Counter used to count INIT errors. */ 1910 int init_err_counter; 1911 1912 /* Count the number of INIT cycles (for doubling timeout). */ 1913 int init_cycle; 1914 1915 /* Default send parameters. */ 1916 __u16 default_stream; 1917 __u16 default_flags; 1918 __u32 default_ppid; 1919 __u32 default_context; 1920 __u32 default_timetolive; 1921 1922 /* Default receive parameters */ 1923 __u32 default_rcv_context; 1924 1925 /* Stream arrays */ 1926 struct sctp_stream stream; 1927 1928 /* All outbound chunks go through this structure. */ 1929 struct sctp_outq outqueue; 1930 1931 /* A smart pipe that will handle reordering and fragmentation, 1932 * as well as handle passing events up to the ULP. 1933 */ 1934 struct sctp_ulpq ulpq; 1935 1936 /* Last TSN that caused an ECNE Chunk to be sent. */ 1937 __u32 last_ecne_tsn; 1938 1939 /* Last TSN that caused a CWR Chunk to be sent. */ 1940 __u32 last_cwr_tsn; 1941 1942 /* How many duplicated TSNs have we seen? */ 1943 int numduptsns; 1944 1945 /* These are to support 1946 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses 1947 * and Enforcement of Flow and Message Limits" 1948 * <draft-ietf-tsvwg-addip-sctp-02.txt> 1949 * or "ADDIP" for short. 1950 */ 1951 1952 1953 1954 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1955 * 1956 * R1) One and only one ASCONF Chunk MAY be in transit and 1957 * unacknowledged at any one time. If a sender, after sending 1958 * an ASCONF chunk, decides it needs to transfer another 1959 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1960 * returns from the previous ASCONF Chunk before sending a 1961 * subsequent ASCONF. Note this restriction binds each side, 1962 * so at any time two ASCONF may be in-transit on any given 1963 * association (one sent from each endpoint). 1964 * 1965 * [This is our one-and-only-one ASCONF in flight. If we do 1966 * not have an ASCONF in flight, this is NULL.] 1967 */ 1968 struct sctp_chunk *addip_last_asconf; 1969 1970 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk. 1971 * 1972 * This is needed to implement itmes E1 - E4 of the updated 1973 * spec. Here is the justification: 1974 * 1975 * Since the peer may bundle multiple ASCONF chunks toward us, 1976 * we now need the ability to cache multiple ACKs. The section 1977 * describes in detail how they are cached and cleaned up. 1978 */ 1979 struct list_head asconf_ack_list; 1980 1981 /* These ASCONF chunks are waiting to be sent. 1982 * 1983 * These chunaks can't be pushed to outqueue until receiving 1984 * ASCONF_ACK for the previous ASCONF indicated by 1985 * addip_last_asconf, so as to guarantee that only one ASCONF 1986 * is in flight at any time. 1987 * 1988 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1989 * 1990 * In defining the ASCONF Chunk transfer procedures, it is 1991 * essential that these transfers MUST NOT cause congestion 1992 * within the network. To achieve this, we place these 1993 * restrictions on the transfer of ASCONF Chunks: 1994 * 1995 * R1) One and only one ASCONF Chunk MAY be in transit and 1996 * unacknowledged at any one time. If a sender, after sending 1997 * an ASCONF chunk, decides it needs to transfer another 1998 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1999 * returns from the previous ASCONF Chunk before sending a 2000 * subsequent ASCONF. Note this restriction binds each side, 2001 * so at any time two ASCONF may be in-transit on any given 2002 * association (one sent from each endpoint). 2003 * 2004 * 2005 * [I really think this is EXACTLY the sort of intelligence 2006 * which already resides in sctp_outq. Please move this 2007 * queue and its supporting logic down there. --piggy] 2008 */ 2009 struct list_head addip_chunk_list; 2010 2011 /* ADDIP Section 4.1 ASCONF Chunk Procedures 2012 * 2013 * A2) A serial number should be assigned to the Chunk. The 2014 * serial number SHOULD be a monotonically increasing 2015 * number. The serial number SHOULD be initialized at 2016 * the start of the association to the same value as the 2017 * Initial TSN and every time a new ASCONF chunk is created 2018 * it is incremented by one after assigning the serial number 2019 * to the newly created chunk. 2020 * 2021 * ADDIP 2022 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF) 2023 * 2024 * Serial Number : 32 bits (unsigned integer) 2025 * 2026 * This value represents a Serial Number for the ASCONF 2027 * Chunk. The valid range of Serial Number is from 0 to 2028 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0 2029 * after reaching 4294967295. 2030 */ 2031 __u32 addip_serial; 2032 int src_out_of_asoc_ok; 2033 union sctp_addr *asconf_addr_del_pending; 2034 struct sctp_transport *new_transport; 2035 2036 /* SCTP AUTH: list of the endpoint shared keys. These 2037 * keys are provided out of band by the user applicaton 2038 * and can't change during the lifetime of the association 2039 */ 2040 struct list_head endpoint_shared_keys; 2041 2042 /* SCTP AUTH: 2043 * The current generated assocaition shared key (secret) 2044 */ 2045 struct sctp_auth_bytes *asoc_shared_key; 2046 struct sctp_shared_key *shkey; 2047 2048 /* SCTP AUTH: hmac id of the first peer requested algorithm 2049 * that we support. 2050 */ 2051 __u16 default_hmac_id; 2052 2053 __u16 active_key_id; 2054 2055 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */ 2056 temp:1, /* Is it a temporary association? */ 2057 pf_expose:2, /* Expose pf state? */ 2058 force_delay:1; 2059 2060 __u8 strreset_enable; 2061 __u8 strreset_outstanding; /* request param count on the fly */ 2062 2063 __u32 strreset_outseq; /* Update after receiving response */ 2064 __u32 strreset_inseq; /* Update after receiving request */ 2065 __u32 strreset_result[2]; /* save the results of last 2 responses */ 2066 2067 struct sctp_chunk *strreset_chunk; /* save request chunk */ 2068 2069 struct sctp_priv_assoc_stats stats; 2070 2071 int sent_cnt_removable; 2072 2073 __u16 subscribe; 2074 2075 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 2076 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 2077 2078 struct rcu_head rcu; 2079 }; 2080 2081 2082 /* An eyecatcher for determining if we are really looking at an 2083 * association data structure. 2084 */ 2085 enum { 2086 SCTP_ASSOC_EYECATCHER = 0xa550c123, 2087 }; 2088 2089 /* Recover the outter association structure. */ 2090 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base) 2091 { 2092 struct sctp_association *asoc; 2093 2094 asoc = container_of(base, struct sctp_association, base); 2095 return asoc; 2096 } 2097 2098 /* These are function signatures for manipulating associations. */ 2099 2100 2101 struct sctp_association * 2102 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk, 2103 enum sctp_scope scope, gfp_t gfp); 2104 void sctp_association_free(struct sctp_association *); 2105 void sctp_association_put(struct sctp_association *); 2106 void sctp_association_hold(struct sctp_association *); 2107 2108 struct sctp_transport *sctp_assoc_choose_alter_transport( 2109 struct sctp_association *, struct sctp_transport *); 2110 void sctp_assoc_update_retran_path(struct sctp_association *); 2111 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *, 2112 const union sctp_addr *); 2113 int sctp_assoc_lookup_laddr(struct sctp_association *asoc, 2114 const union sctp_addr *laddr); 2115 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *, 2116 const union sctp_addr *address, 2117 const gfp_t gfp, 2118 const int peer_state); 2119 void sctp_assoc_del_peer(struct sctp_association *asoc, 2120 const union sctp_addr *addr); 2121 void sctp_assoc_rm_peer(struct sctp_association *asoc, 2122 struct sctp_transport *peer); 2123 void sctp_assoc_control_transport(struct sctp_association *asoc, 2124 struct sctp_transport *transport, 2125 enum sctp_transport_cmd command, 2126 sctp_sn_error_t error); 2127 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32); 2128 void sctp_assoc_migrate(struct sctp_association *, struct sock *); 2129 int sctp_assoc_update(struct sctp_association *old, 2130 struct sctp_association *new); 2131 2132 __u32 sctp_association_get_next_tsn(struct sctp_association *); 2133 2134 void sctp_assoc_update_frag_point(struct sctp_association *asoc); 2135 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu); 2136 void sctp_assoc_sync_pmtu(struct sctp_association *asoc); 2137 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int); 2138 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int); 2139 void sctp_assoc_set_primary(struct sctp_association *, 2140 struct sctp_transport *); 2141 void sctp_assoc_del_nonprimary_peers(struct sctp_association *, 2142 struct sctp_transport *); 2143 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, 2144 enum sctp_scope scope, gfp_t gfp); 2145 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *, 2146 struct sctp_cookie*, 2147 gfp_t gfp); 2148 int sctp_assoc_set_id(struct sctp_association *, gfp_t); 2149 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc); 2150 struct sctp_chunk *sctp_assoc_lookup_asconf_ack( 2151 const struct sctp_association *asoc, 2152 __be32 serial); 2153 void sctp_asconf_queue_teardown(struct sctp_association *asoc); 2154 2155 int sctp_cmp_addr_exact(const union sctp_addr *ss1, 2156 const union sctp_addr *ss2); 2157 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc); 2158 2159 /* A convenience structure to parse out SCTP specific CMSGs. */ 2160 struct sctp_cmsgs { 2161 struct sctp_initmsg *init; 2162 struct sctp_sndrcvinfo *srinfo; 2163 struct sctp_sndinfo *sinfo; 2164 struct sctp_prinfo *prinfo; 2165 struct sctp_authinfo *authinfo; 2166 struct msghdr *addrs_msg; 2167 }; 2168 2169 /* Structure for tracking memory objects */ 2170 struct sctp_dbg_objcnt_entry { 2171 char *label; 2172 atomic_t *counter; 2173 }; 2174 2175 #endif /* __sctp_structs_h__ */ 2176