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 /* Receive to here while partial delivery is in effect. */ 230 struct sk_buff_head pd_lobby; 231 232 /* These must be the last fields, as they will skipped on copies, 233 * like on accept and peeloff operations 234 */ 235 struct list_head auto_asconf_list; 236 int do_auto_asconf; 237 }; 238 239 static inline struct sctp_sock *sctp_sk(const struct sock *sk) 240 { 241 return (struct sctp_sock *)sk; 242 } 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[0]; 330 }; 331 332 333 /* The format of our cookie that we send to our peer. */ 334 struct sctp_signed_cookie { 335 __u8 signature[SCTP_SECRET_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 }; 384 385 int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt, 386 gfp_t gfp); 387 int sctp_stream_init_ext(struct sctp_stream *stream, __u16 sid); 388 void sctp_stream_free(struct sctp_stream *stream); 389 void sctp_stream_clear(struct sctp_stream *stream); 390 void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new); 391 392 /* What is the current SSN number for this stream? */ 393 #define sctp_ssn_peek(stream, type, sid) \ 394 (sctp_stream_##type((stream), (sid))->ssn) 395 396 /* Return the next SSN number for this stream. */ 397 #define sctp_ssn_next(stream, type, sid) \ 398 (sctp_stream_##type((stream), (sid))->ssn++) 399 400 /* Skip over this ssn and all below. */ 401 #define sctp_ssn_skip(stream, type, sid, ssn) \ 402 (sctp_stream_##type((stream), (sid))->ssn = ssn + 1) 403 404 /* What is the current MID number for this stream? */ 405 #define sctp_mid_peek(stream, type, sid) \ 406 (sctp_stream_##type((stream), (sid))->mid) 407 408 /* Return the next MID number for this stream. */ 409 #define sctp_mid_next(stream, type, sid) \ 410 (sctp_stream_##type((stream), (sid))->mid++) 411 412 /* Skip over this mid and all below. */ 413 #define sctp_mid_skip(stream, type, sid, mid) \ 414 (sctp_stream_##type((stream), (sid))->mid = mid + 1) 415 416 /* What is the current MID_uo number for this stream? */ 417 #define sctp_mid_uo_peek(stream, type, sid) \ 418 (sctp_stream_##type((stream), (sid))->mid_uo) 419 420 /* Return the next MID_uo number for this stream. */ 421 #define sctp_mid_uo_next(stream, type, sid) \ 422 (sctp_stream_##type((stream), (sid))->mid_uo++) 423 424 /* 425 * Pointers to address related SCTP functions. 426 * (i.e. things that depend on the address family.) 427 */ 428 struct sctp_af { 429 int (*sctp_xmit) (struct sk_buff *skb, 430 struct sctp_transport *); 431 int (*setsockopt) (struct sock *sk, 432 int level, 433 int optname, 434 char __user *optval, 435 unsigned int optlen); 436 int (*getsockopt) (struct sock *sk, 437 int level, 438 int optname, 439 char __user *optval, 440 int __user *optlen); 441 int (*compat_setsockopt) (struct sock *sk, 442 int level, 443 int optname, 444 char __user *optval, 445 unsigned int optlen); 446 int (*compat_getsockopt) (struct sock *sk, 447 int level, 448 int optname, 449 char __user *optval, 450 int __user *optlen); 451 void (*get_dst) (struct sctp_transport *t, 452 union sctp_addr *saddr, 453 struct flowi *fl, 454 struct sock *sk); 455 void (*get_saddr) (struct sctp_sock *sk, 456 struct sctp_transport *t, 457 struct flowi *fl); 458 void (*copy_addrlist) (struct list_head *, 459 struct net_device *); 460 int (*cmp_addr) (const union sctp_addr *addr1, 461 const union sctp_addr *addr2); 462 void (*addr_copy) (union sctp_addr *dst, 463 union sctp_addr *src); 464 void (*from_skb) (union sctp_addr *, 465 struct sk_buff *skb, 466 int saddr); 467 void (*from_sk) (union sctp_addr *, 468 struct sock *sk); 469 void (*from_addr_param) (union sctp_addr *, 470 union sctp_addr_param *, 471 __be16 port, int iif); 472 int (*to_addr_param) (const union sctp_addr *, 473 union sctp_addr_param *); 474 int (*addr_valid) (union sctp_addr *, 475 struct sctp_sock *, 476 const struct sk_buff *); 477 enum sctp_scope (*scope)(union sctp_addr *); 478 void (*inaddr_any) (union sctp_addr *, __be16); 479 int (*is_any) (const union sctp_addr *); 480 int (*available) (union sctp_addr *, 481 struct sctp_sock *); 482 int (*skb_iif) (const struct sk_buff *sk); 483 int (*is_ce) (const struct sk_buff *sk); 484 void (*seq_dump_addr)(struct seq_file *seq, 485 union sctp_addr *addr); 486 void (*ecn_capable)(struct sock *sk); 487 __u16 net_header_len; 488 int sockaddr_len; 489 int (*ip_options_len)(struct sock *sk); 490 sa_family_t sa_family; 491 struct list_head list; 492 }; 493 494 struct sctp_af *sctp_get_af_specific(sa_family_t); 495 int sctp_register_af(struct sctp_af *); 496 497 /* Protocol family functions. */ 498 struct sctp_pf { 499 void (*event_msgname)(struct sctp_ulpevent *, char *, int *); 500 void (*skb_msgname) (struct sk_buff *, char *, int *); 501 int (*af_supported) (sa_family_t, struct sctp_sock *); 502 int (*cmp_addr) (const union sctp_addr *, 503 const union sctp_addr *, 504 struct sctp_sock *); 505 int (*bind_verify) (struct sctp_sock *, union sctp_addr *); 506 int (*send_verify) (struct sctp_sock *, union sctp_addr *); 507 int (*supported_addrs)(const struct sctp_sock *, __be16 *); 508 struct sock *(*create_accept_sk) (struct sock *sk, 509 struct sctp_association *asoc, 510 bool kern); 511 int (*addr_to_user)(struct sctp_sock *sk, union sctp_addr *addr); 512 void (*to_sk_saddr)(union sctp_addr *, struct sock *sk); 513 void (*to_sk_daddr)(union sctp_addr *, struct sock *sk); 514 void (*copy_ip_options)(struct sock *sk, struct sock *newsk); 515 struct sctp_af *af; 516 }; 517 518 519 /* Structure to track chunk fragments that have been acked, but peer 520 * fragments of the same message have not. 521 */ 522 struct sctp_datamsg { 523 /* Chunks waiting to be submitted to lower layer. */ 524 struct list_head chunks; 525 /* Reference counting. */ 526 refcount_t refcnt; 527 /* When is this message no longer interesting to the peer? */ 528 unsigned long expires_at; 529 /* Did the messenge fail to send? */ 530 int send_error; 531 u8 send_failed:1, 532 can_delay:1, /* should this message be Nagle delayed */ 533 abandoned:1; /* should this message be abandoned */ 534 }; 535 536 struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *, 537 struct sctp_sndrcvinfo *, 538 struct iov_iter *); 539 void sctp_datamsg_free(struct sctp_datamsg *); 540 void sctp_datamsg_put(struct sctp_datamsg *); 541 void sctp_chunk_fail(struct sctp_chunk *, int error); 542 int sctp_chunk_abandoned(struct sctp_chunk *); 543 544 /* RFC2960 1.4 Key Terms 545 * 546 * o Chunk: A unit of information within an SCTP packet, consisting of 547 * a chunk header and chunk-specific content. 548 * 549 * As a matter of convenience, we remember the SCTP common header for 550 * each chunk as well as a few other header pointers... 551 */ 552 struct sctp_chunk { 553 struct list_head list; 554 555 refcount_t refcnt; 556 557 /* How many times this chunk have been sent, for prsctp RTX policy */ 558 int sent_count; 559 560 union { 561 /* This is our link to the per-transport transmitted list. */ 562 struct list_head transmitted_list; 563 /* List in specific stream outq */ 564 struct list_head stream_list; 565 }; 566 567 /* This field is used by chunks that hold fragmented data. 568 * For the first fragment this is the list that holds the rest of 569 * fragments. For the remaining fragments, this is the link to the 570 * frag_list maintained in the first fragment. 571 */ 572 struct list_head frag_list; 573 574 /* This points to the sk_buff containing the actual data. */ 575 struct sk_buff *skb; 576 577 union { 578 /* In case of GSO packets, this will store the head one */ 579 struct sk_buff *head_skb; 580 /* In case of auth enabled, this will point to the shkey */ 581 struct sctp_shared_key *shkey; 582 }; 583 584 /* These are the SCTP headers by reverse order in a packet. 585 * Note that some of these may happen more than once. In that 586 * case, we point at the "current" one, whatever that means 587 * for that level of header. 588 */ 589 590 /* We point this at the FIRST TLV parameter to chunk_hdr. */ 591 union sctp_params param_hdr; 592 union { 593 __u8 *v; 594 struct sctp_datahdr *data_hdr; 595 struct sctp_inithdr *init_hdr; 596 struct sctp_sackhdr *sack_hdr; 597 struct sctp_heartbeathdr *hb_hdr; 598 struct sctp_sender_hb_info *hbs_hdr; 599 struct sctp_shutdownhdr *shutdown_hdr; 600 struct sctp_signed_cookie *cookie_hdr; 601 struct sctp_ecnehdr *ecne_hdr; 602 struct sctp_cwrhdr *ecn_cwr_hdr; 603 struct sctp_errhdr *err_hdr; 604 struct sctp_addiphdr *addip_hdr; 605 struct sctp_fwdtsn_hdr *fwdtsn_hdr; 606 struct sctp_authhdr *auth_hdr; 607 struct sctp_idatahdr *idata_hdr; 608 struct sctp_ifwdtsn_hdr *ifwdtsn_hdr; 609 } subh; 610 611 __u8 *chunk_end; 612 613 struct sctp_chunkhdr *chunk_hdr; 614 struct sctphdr *sctp_hdr; 615 616 /* This needs to be recoverable for SCTP_SEND_FAILED events. */ 617 struct sctp_sndrcvinfo sinfo; 618 619 /* Which association does this belong to? */ 620 struct sctp_association *asoc; 621 622 /* What endpoint received this chunk? */ 623 struct sctp_ep_common *rcvr; 624 625 /* We fill this in if we are calculating RTT. */ 626 unsigned long sent_at; 627 628 /* What is the origin IP address for this chunk? */ 629 union sctp_addr source; 630 /* Destination address for this chunk. */ 631 union sctp_addr dest; 632 633 /* For outbound message, track all fragments for SEND_FAILED. */ 634 struct sctp_datamsg *msg; 635 636 /* For an inbound chunk, this tells us where it came from. 637 * For an outbound chunk, it tells us where we'd like it to 638 * go. It is NULL if we have no preference. 639 */ 640 struct sctp_transport *transport; 641 642 /* SCTP-AUTH: For the special case inbound processing of COOKIE-ECHO 643 * we need save a pointer to the AUTH chunk, since the SCTP-AUTH 644 * spec violates the principle premis that all chunks are processed 645 * in order. 646 */ 647 struct sk_buff *auth_chunk; 648 649 #define SCTP_CAN_FRTX 0x0 650 #define SCTP_NEED_FRTX 0x1 651 #define SCTP_DONT_FRTX 0x2 652 __u16 rtt_in_progress:1, /* This chunk used for RTT calc? */ 653 has_tsn:1, /* Does this chunk have a TSN yet? */ 654 has_ssn:1, /* Does this chunk have a SSN yet? */ 655 #define has_mid has_ssn 656 singleton:1, /* Only chunk in the packet? */ 657 end_of_packet:1, /* Last chunk in the packet? */ 658 ecn_ce_done:1, /* Have we processed the ECN CE bit? */ 659 pdiscard:1, /* Discard the whole packet now? */ 660 tsn_gap_acked:1, /* Is this chunk acked by a GAP ACK? */ 661 data_accepted:1, /* At least 1 chunk accepted */ 662 auth:1, /* IN: was auth'ed | OUT: needs auth */ 663 has_asconf:1, /* IN: have seen an asconf before */ 664 tsn_missing_report:2, /* Data chunk missing counter. */ 665 fast_retransmit:2; /* Is this chunk fast retransmitted? */ 666 }; 667 668 #define sctp_chunk_retransmitted(chunk) (chunk->sent_count > 1) 669 void sctp_chunk_hold(struct sctp_chunk *); 670 void sctp_chunk_put(struct sctp_chunk *); 671 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len, 672 struct iov_iter *from); 673 void sctp_chunk_free(struct sctp_chunk *); 674 void *sctp_addto_chunk(struct sctp_chunk *, int len, const void *data); 675 struct sctp_chunk *sctp_chunkify(struct sk_buff *, 676 const struct sctp_association *, 677 struct sock *, gfp_t gfp); 678 void sctp_init_addrs(struct sctp_chunk *, union sctp_addr *, 679 union sctp_addr *); 680 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk); 681 682 static inline __u16 sctp_chunk_stream_no(struct sctp_chunk *ch) 683 { 684 return ntohs(ch->subh.data_hdr->stream); 685 } 686 687 enum { 688 SCTP_ADDR_NEW, /* new address added to assoc/ep */ 689 SCTP_ADDR_SRC, /* address can be used as source */ 690 SCTP_ADDR_DEL, /* address about to be deleted */ 691 }; 692 693 /* This is a structure for holding either an IPv6 or an IPv4 address. */ 694 struct sctp_sockaddr_entry { 695 struct list_head list; 696 struct rcu_head rcu; 697 union sctp_addr a; 698 __u8 state; 699 __u8 valid; 700 }; 701 702 #define SCTP_ADDRESS_TICK_DELAY 500 703 704 /* This structure holds lists of chunks as we are assembling for 705 * transmission. 706 */ 707 struct sctp_packet { 708 /* These are the SCTP header values (host order) for the packet. */ 709 __u16 source_port; 710 __u16 destination_port; 711 __u32 vtag; 712 713 /* This contains the payload chunks. */ 714 struct list_head chunk_list; 715 716 /* This is the overhead of the sctp and ip headers. */ 717 size_t overhead; 718 /* This is the total size of all chunks INCLUDING padding. */ 719 size_t size; 720 /* This is the maximum size this packet may have */ 721 size_t max_size; 722 723 /* The packet is destined for this transport address. 724 * The function we finally use to pass down to the next lower 725 * layer lives in the transport structure. 726 */ 727 struct sctp_transport *transport; 728 729 /* pointer to the auth chunk for this packet */ 730 struct sctp_chunk *auth; 731 732 u8 has_cookie_echo:1, /* This packet contains a COOKIE-ECHO chunk. */ 733 has_sack:1, /* This packet contains a SACK chunk. */ 734 has_auth:1, /* This packet contains an AUTH chunk */ 735 has_data:1, /* This packet contains at least 1 DATA chunk */ 736 ipfragok:1; /* So let ip fragment this packet */ 737 }; 738 739 void sctp_packet_init(struct sctp_packet *, struct sctp_transport *, 740 __u16 sport, __u16 dport); 741 void sctp_packet_config(struct sctp_packet *, __u32 vtag, int); 742 enum sctp_xmit sctp_packet_transmit_chunk(struct sctp_packet *packet, 743 struct sctp_chunk *chunk, 744 int one_packet, gfp_t gfp); 745 enum sctp_xmit sctp_packet_append_chunk(struct sctp_packet *packet, 746 struct sctp_chunk *chunk); 747 int sctp_packet_transmit(struct sctp_packet *, gfp_t); 748 void sctp_packet_free(struct sctp_packet *); 749 750 static inline int sctp_packet_empty(struct sctp_packet *packet) 751 { 752 return packet->size == packet->overhead; 753 } 754 755 /* This represents a remote transport address. 756 * For local transport addresses, we just use union sctp_addr. 757 * 758 * RFC2960 Section 1.4 Key Terms 759 * 760 * o Transport address: A Transport Address is traditionally defined 761 * by Network Layer address, Transport Layer protocol and Transport 762 * Layer port number. In the case of SCTP running over IP, a 763 * transport address is defined by the combination of an IP address 764 * and an SCTP port number (where SCTP is the Transport protocol). 765 * 766 * RFC2960 Section 7.1 SCTP Differences from TCP Congestion control 767 * 768 * o The sender keeps a separate congestion control parameter set for 769 * each of the destination addresses it can send to (not each 770 * source-destination pair but for each destination). The parameters 771 * should decay if the address is not used for a long enough time 772 * period. 773 * 774 */ 775 struct sctp_transport { 776 /* A list of transports. */ 777 struct list_head transports; 778 struct rhlist_head node; 779 780 /* Reference counting. */ 781 refcount_t refcnt; 782 /* RTO-Pending : A flag used to track if one of the DATA 783 * chunks sent to this address is currently being 784 * used to compute a RTT. If this flag is 0, 785 * the next DATA chunk sent to this destination 786 * should be used to compute a RTT and this flag 787 * should be set. Every time the RTT 788 * calculation completes (i.e. the DATA chunk 789 * is SACK'd) clear this flag. 790 */ 791 __u32 rto_pending:1, 792 793 /* 794 * hb_sent : a flag that signals that we have a pending 795 * heartbeat. 796 */ 797 hb_sent:1, 798 799 /* Is the Path MTU update pending on this tranport */ 800 pmtu_pending:1, 801 802 dst_pending_confirm:1, /* need to confirm neighbour */ 803 804 /* Has this transport moved the ctsn since we last sacked */ 805 sack_generation:1; 806 u32 dst_cookie; 807 808 struct flowi fl; 809 810 /* This is the peer's IP address and port. */ 811 union sctp_addr ipaddr; 812 813 /* These are the functions we call to handle LLP stuff. */ 814 struct sctp_af *af_specific; 815 816 /* Which association do we belong to? */ 817 struct sctp_association *asoc; 818 819 /* RFC2960 820 * 821 * 12.3 Per Transport Address Data 822 * 823 * For each destination transport address in the peer's 824 * address list derived from the INIT or INIT ACK chunk, a 825 * number of data elements needs to be maintained including: 826 */ 827 /* RTO : The current retransmission timeout value. */ 828 unsigned long rto; 829 830 __u32 rtt; /* This is the most recent RTT. */ 831 832 /* RTTVAR : The current RTT variation. */ 833 __u32 rttvar; 834 835 /* SRTT : The current smoothed round trip time. */ 836 __u32 srtt; 837 838 /* 839 * These are the congestion stats. 840 */ 841 /* cwnd : The current congestion window. */ 842 __u32 cwnd; /* This is the actual cwnd. */ 843 844 /* ssthresh : The current slow start threshold value. */ 845 __u32 ssthresh; 846 847 /* partial : The tracking method for increase of cwnd when in 848 * bytes acked : congestion avoidance mode (see Section 6.2.2) 849 */ 850 __u32 partial_bytes_acked; 851 852 /* Data that has been sent, but not acknowledged. */ 853 __u32 flight_size; 854 855 __u32 burst_limited; /* Holds old cwnd when max.burst is applied */ 856 857 /* Destination */ 858 struct dst_entry *dst; 859 /* Source address. */ 860 union sctp_addr saddr; 861 862 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 863 * the destination address every heartbeat interval. 864 */ 865 unsigned long hbinterval; 866 867 /* SACK delay timeout */ 868 unsigned long sackdelay; 869 __u32 sackfreq; 870 871 atomic_t mtu_info; 872 873 /* When was the last time that we heard from this transport? We use 874 * this to pick new active and retran paths. 875 */ 876 ktime_t last_time_heard; 877 878 /* When was the last time that we sent a chunk using this 879 * transport? We use this to check for idle transports 880 */ 881 unsigned long last_time_sent; 882 883 /* Last time(in jiffies) when cwnd is reduced due to the congestion 884 * indication based on ECNE chunk. 885 */ 886 unsigned long last_time_ecne_reduced; 887 888 /* This is the max_retrans value for the transport and will 889 * be initialized from the assocs value. This can be changed 890 * using the SCTP_SET_PEER_ADDR_PARAMS socket option. 891 */ 892 __u16 pathmaxrxt; 893 894 __u32 flowlabel; 895 __u8 dscp; 896 897 /* This is the partially failed retrans value for the transport 898 * and will be initialized from the assocs value. This can be changed 899 * using the SCTP_PEER_ADDR_THLDS socket option 900 */ 901 __u16 pf_retrans; 902 /* Used for primary path switchover. */ 903 __u16 ps_retrans; 904 /* PMTU : The current known path MTU. */ 905 __u32 pathmtu; 906 907 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 908 __u32 param_flags; 909 910 /* The number of times INIT has been sent on this transport. */ 911 int init_sent_count; 912 913 /* state : The current state of this destination, 914 * : i.e. SCTP_ACTIVE, SCTP_INACTIVE, SCTP_UNKNOWN. 915 */ 916 int state; 917 918 /* These are the error stats for this destination. */ 919 920 /* Error count : The current error count for this destination. */ 921 unsigned short error_count; 922 923 /* Per : A timer used by each destination. 924 * Destination : 925 * Timer : 926 * 927 * [Everywhere else in the text this is called T3-rtx. -ed] 928 */ 929 struct timer_list T3_rtx_timer; 930 931 /* Heartbeat timer is per destination. */ 932 struct timer_list hb_timer; 933 934 /* Timer to handle ICMP proto unreachable envets */ 935 struct timer_list proto_unreach_timer; 936 937 /* Timer to handler reconf chunk rtx */ 938 struct timer_list reconf_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 /* 64-bit random number sent with heartbeat. */ 983 __u64 hb_nonce; 984 985 struct rcu_head rcu; 986 }; 987 988 struct sctp_transport *sctp_transport_new(struct net *, const union sctp_addr *, 989 gfp_t); 990 void sctp_transport_set_owner(struct sctp_transport *, 991 struct sctp_association *); 992 void sctp_transport_route(struct sctp_transport *, union sctp_addr *, 993 struct sctp_sock *); 994 void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk); 995 void sctp_transport_free(struct sctp_transport *); 996 void sctp_transport_reset_t3_rtx(struct sctp_transport *); 997 void sctp_transport_reset_hb_timer(struct sctp_transport *); 998 void sctp_transport_reset_reconf_timer(struct sctp_transport *transport); 999 int sctp_transport_hold(struct sctp_transport *); 1000 void sctp_transport_put(struct sctp_transport *); 1001 void sctp_transport_update_rto(struct sctp_transport *, __u32); 1002 void sctp_transport_raise_cwnd(struct sctp_transport *, __u32, __u32); 1003 void sctp_transport_lower_cwnd(struct sctp_transport *t, 1004 enum sctp_lower_cwnd reason); 1005 void sctp_transport_burst_limited(struct sctp_transport *); 1006 void sctp_transport_burst_reset(struct sctp_transport *); 1007 unsigned long sctp_transport_timeout(struct sctp_transport *); 1008 void sctp_transport_reset(struct sctp_transport *t); 1009 bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu); 1010 void sctp_transport_immediate_rtx(struct sctp_transport *); 1011 void sctp_transport_dst_release(struct sctp_transport *t); 1012 void sctp_transport_dst_confirm(struct sctp_transport *t); 1013 1014 1015 /* This is the structure we use to queue packets as they come into 1016 * SCTP. We write packets to it and read chunks from it. 1017 */ 1018 struct sctp_inq { 1019 /* This is actually a queue of sctp_chunk each 1020 * containing a partially decoded packet. 1021 */ 1022 struct list_head in_chunk_list; 1023 /* This is the packet which is currently off the in queue and is 1024 * being worked on through the inbound chunk processing. 1025 */ 1026 struct sctp_chunk *in_progress; 1027 1028 /* This is the delayed task to finish delivering inbound 1029 * messages. 1030 */ 1031 struct work_struct immediate; 1032 }; 1033 1034 void sctp_inq_init(struct sctp_inq *); 1035 void sctp_inq_free(struct sctp_inq *); 1036 void sctp_inq_push(struct sctp_inq *, struct sctp_chunk *packet); 1037 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *); 1038 struct sctp_chunkhdr *sctp_inq_peek(struct sctp_inq *); 1039 void sctp_inq_set_th_handler(struct sctp_inq *, work_func_t); 1040 1041 /* This is the structure we use to hold outbound chunks. You push 1042 * chunks in and they automatically pop out the other end as bundled 1043 * packets (it calls (*output_handler)()). 1044 * 1045 * This structure covers sections 6.3, 6.4, 6.7, 6.8, 6.10, 7., 8.1, 1046 * and 8.2 of the v13 draft. 1047 * 1048 * It handles retransmissions. The connection to the timeout portion 1049 * of the state machine is through sctp_..._timeout() and timeout_handler. 1050 * 1051 * If you feed it SACKs, it will eat them. 1052 * 1053 * If you give it big chunks, it will fragment them. 1054 * 1055 * It assigns TSN's to data chunks. This happens at the last possible 1056 * instant before transmission. 1057 * 1058 * When free()'d, it empties itself out via output_handler(). 1059 */ 1060 struct sctp_outq { 1061 struct sctp_association *asoc; 1062 1063 /* Data pending that has never been transmitted. */ 1064 struct list_head out_chunk_list; 1065 1066 /* Stream scheduler being used */ 1067 struct sctp_sched_ops *sched; 1068 1069 unsigned int out_qlen; /* Total length of queued data chunks. */ 1070 1071 /* Error of send failed, may used in SCTP_SEND_FAILED event. */ 1072 unsigned int error; 1073 1074 /* These are control chunks we want to send. */ 1075 struct list_head control_chunk_list; 1076 1077 /* These are chunks that have been sacked but are above the 1078 * CTSN, or cumulative tsn ack point. 1079 */ 1080 struct list_head sacked; 1081 1082 /* Put chunks on this list to schedule them for 1083 * retransmission. 1084 */ 1085 struct list_head retransmit; 1086 1087 /* Put chunks on this list to save them for FWD TSN processing as 1088 * they were abandoned. 1089 */ 1090 struct list_head abandoned; 1091 1092 /* How many unackd bytes do we have in-flight? */ 1093 __u32 outstanding_bytes; 1094 1095 /* Are we doing fast-rtx on this queue */ 1096 char fast_rtx; 1097 1098 /* Corked? */ 1099 char cork; 1100 }; 1101 1102 void sctp_outq_init(struct sctp_association *, struct sctp_outq *); 1103 void sctp_outq_teardown(struct sctp_outq *); 1104 void sctp_outq_free(struct sctp_outq*); 1105 void sctp_outq_tail(struct sctp_outq *, struct sctp_chunk *chunk, gfp_t); 1106 int sctp_outq_sack(struct sctp_outq *, struct sctp_chunk *); 1107 int sctp_outq_is_empty(const struct sctp_outq *); 1108 void sctp_outq_restart(struct sctp_outq *); 1109 1110 void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport, 1111 enum sctp_retransmit_reason reason); 1112 void sctp_retransmit_mark(struct sctp_outq *, struct sctp_transport *, __u8); 1113 void sctp_outq_uncork(struct sctp_outq *, gfp_t gfp); 1114 void sctp_prsctp_prune(struct sctp_association *asoc, 1115 struct sctp_sndrcvinfo *sinfo, int msg_len); 1116 void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn); 1117 /* Uncork and flush an outqueue. */ 1118 static inline void sctp_outq_cork(struct sctp_outq *q) 1119 { 1120 q->cork = 1; 1121 } 1122 1123 /* SCTP skb control block. 1124 * sctp_input_cb is currently used on rx and sock rx queue 1125 */ 1126 struct sctp_input_cb { 1127 union { 1128 struct inet_skb_parm h4; 1129 #if IS_ENABLED(CONFIG_IPV6) 1130 struct inet6_skb_parm h6; 1131 #endif 1132 } header; 1133 struct sctp_chunk *chunk; 1134 struct sctp_af *af; 1135 }; 1136 #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0])) 1137 1138 struct sctp_output_cb { 1139 struct sk_buff *last; 1140 }; 1141 #define SCTP_OUTPUT_CB(__skb) ((struct sctp_output_cb *)&((__skb)->cb[0])) 1142 1143 static inline const struct sk_buff *sctp_gso_headskb(const struct sk_buff *skb) 1144 { 1145 const struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; 1146 1147 return chunk->head_skb ? : skb; 1148 } 1149 1150 /* These bind address data fields common between endpoints and associations */ 1151 struct sctp_bind_addr { 1152 1153 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1154 * 1155 * SCTP Port: The local SCTP port number the endpoint is 1156 * bound to. 1157 */ 1158 __u16 port; 1159 1160 /* RFC 2960 12.1 Parameters necessary for the SCTP instance 1161 * 1162 * Address List: The list of IP addresses that this instance 1163 * has bound. This information is passed to one's 1164 * peer(s) in INIT and INIT ACK chunks. 1165 */ 1166 struct list_head address_list; 1167 }; 1168 1169 void sctp_bind_addr_init(struct sctp_bind_addr *, __u16 port); 1170 void sctp_bind_addr_free(struct sctp_bind_addr *); 1171 int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest, 1172 const struct sctp_bind_addr *src, 1173 enum sctp_scope scope, gfp_t gfp, 1174 int flags); 1175 int sctp_bind_addr_dup(struct sctp_bind_addr *dest, 1176 const struct sctp_bind_addr *src, 1177 gfp_t gfp); 1178 int sctp_add_bind_addr(struct sctp_bind_addr *, union sctp_addr *, 1179 int new_size, __u8 addr_state, gfp_t gfp); 1180 int sctp_del_bind_addr(struct sctp_bind_addr *, union sctp_addr *); 1181 int sctp_bind_addr_match(struct sctp_bind_addr *, const union sctp_addr *, 1182 struct sctp_sock *); 1183 int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *, 1184 struct sctp_sock *, struct sctp_sock *); 1185 int sctp_bind_addr_state(const struct sctp_bind_addr *bp, 1186 const union sctp_addr *addr); 1187 int sctp_bind_addrs_check(struct sctp_sock *sp, 1188 struct sctp_sock *sp2, int cnt2); 1189 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp, 1190 const union sctp_addr *addrs, 1191 int addrcnt, 1192 struct sctp_sock *opt); 1193 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp, 1194 int *addrs_len, 1195 gfp_t gfp); 1196 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw, int len, 1197 __u16 port, gfp_t gfp); 1198 1199 enum sctp_scope sctp_scope(const union sctp_addr *addr); 1200 int sctp_in_scope(struct net *net, const union sctp_addr *addr, 1201 const enum sctp_scope scope); 1202 int sctp_is_any(struct sock *sk, const union sctp_addr *addr); 1203 int sctp_is_ep_boundall(struct sock *sk); 1204 1205 1206 /* What type of endpoint? */ 1207 enum sctp_endpoint_type { 1208 SCTP_EP_TYPE_SOCKET, 1209 SCTP_EP_TYPE_ASSOCIATION, 1210 }; 1211 1212 /* 1213 * A common base class to bridge the implmentation view of a 1214 * socket (usually listening) endpoint versus an association's 1215 * local endpoint. 1216 * This common structure is useful for several purposes: 1217 * 1) Common interface for lookup routines. 1218 * a) Subfunctions work for either endpoint or association 1219 * b) Single interface to lookup allows hiding the lookup lock rather 1220 * than acquiring it externally. 1221 * 2) Common interface for the inbound chunk handling/state machine. 1222 * 3) Common object handling routines for reference counting, etc. 1223 * 4) Disentangle association lookup from endpoint lookup, where we 1224 * do not have to find our endpoint to find our association. 1225 * 1226 */ 1227 1228 struct sctp_ep_common { 1229 /* Fields to help us manage our entries in the hash tables. */ 1230 struct hlist_node node; 1231 int hashent; 1232 1233 /* Runtime type information. What kind of endpoint is this? */ 1234 enum sctp_endpoint_type type; 1235 1236 /* Some fields to help us manage this object. 1237 * refcnt - Reference count access to this object. 1238 * dead - Do not attempt to use this object. 1239 */ 1240 refcount_t refcnt; 1241 bool dead; 1242 1243 /* What socket does this endpoint belong to? */ 1244 struct sock *sk; 1245 1246 /* Cache netns and it won't change once set */ 1247 struct net *net; 1248 1249 /* This is where we receive inbound chunks. */ 1250 struct sctp_inq inqueue; 1251 1252 /* This substructure includes the defining parameters of the 1253 * endpoint: 1254 * bind_addr.port is our shared port number. 1255 * bind_addr.address_list is our set of local IP addresses. 1256 */ 1257 struct sctp_bind_addr bind_addr; 1258 }; 1259 1260 1261 /* RFC Section 1.4 Key Terms 1262 * 1263 * o SCTP endpoint: The logical sender/receiver of SCTP packets. On a 1264 * multi-homed host, an SCTP endpoint is represented to its peers as a 1265 * combination of a set of eligible destination transport addresses to 1266 * which SCTP packets can be sent and a set of eligible source 1267 * transport addresses from which SCTP packets can be received. 1268 * All transport addresses used by an SCTP endpoint must use the 1269 * same port number, but can use multiple IP addresses. A transport 1270 * address used by an SCTP endpoint must not be used by another 1271 * SCTP endpoint. In other words, a transport address is unique 1272 * to an SCTP endpoint. 1273 * 1274 * From an implementation perspective, each socket has one of these. 1275 * A TCP-style socket will have exactly one association on one of 1276 * these. An UDP-style socket will have multiple associations hanging 1277 * off one of these. 1278 */ 1279 1280 struct sctp_endpoint { 1281 /* Common substructure for endpoint and association. */ 1282 struct sctp_ep_common base; 1283 1284 /* Associations: A list of current associations and mappings 1285 * to the data consumers for each association. This 1286 * may be in the form of a hash table or other 1287 * implementation dependent structure. The data 1288 * consumers may be process identification 1289 * information such as file descriptors, named pipe 1290 * pointer, or table pointers dependent on how SCTP 1291 * is implemented. 1292 */ 1293 /* This is really a list of struct sctp_association entries. */ 1294 struct list_head asocs; 1295 1296 /* Secret Key: A secret key used by this endpoint to compute 1297 * the MAC. This SHOULD be a cryptographic quality 1298 * random number with a sufficient length. 1299 * Discussion in [RFC1750] can be helpful in 1300 * selection of the key. 1301 */ 1302 __u8 secret_key[SCTP_SECRET_SIZE]; 1303 1304 /* digest: This is a digest of the sctp cookie. This field is 1305 * only used on the receive path when we try to validate 1306 * that the cookie has not been tampered with. We put 1307 * this here so we pre-allocate this once and can re-use 1308 * on every receive. 1309 */ 1310 __u8 *digest; 1311 1312 /* sendbuf acct. policy. */ 1313 __u32 sndbuf_policy; 1314 1315 /* rcvbuf acct. policy. */ 1316 __u32 rcvbuf_policy; 1317 1318 /* SCTP AUTH: array of the HMACs that will be allocated 1319 * we need this per association so that we don't serialize 1320 */ 1321 struct crypto_shash **auth_hmacs; 1322 1323 /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */ 1324 struct sctp_hmac_algo_param *auth_hmacs_list; 1325 1326 /* SCTP-AUTH: chunks to authenticate encoded into parameter */ 1327 struct sctp_chunks_param *auth_chunk_list; 1328 1329 /* SCTP-AUTH: endpoint shared keys */ 1330 struct list_head endpoint_shared_keys; 1331 __u16 active_key_id; 1332 __u8 ecn_enable:1, 1333 auth_enable:1, 1334 intl_enable:1, 1335 prsctp_enable:1, 1336 asconf_enable:1, 1337 reconf_enable:1; 1338 1339 __u8 strreset_enable; 1340 1341 /* Security identifiers from incoming (INIT). These are set by 1342 * security_sctp_assoc_request(). These will only be used by 1343 * SCTP TCP type sockets and peeled off connections as they 1344 * cause a new socket to be generated. security_sctp_sk_clone() 1345 * will then plug these into the new socket. 1346 */ 1347 1348 u32 secid; 1349 u32 peer_secid; 1350 }; 1351 1352 /* Recover the outter endpoint structure. */ 1353 static inline struct sctp_endpoint *sctp_ep(struct sctp_ep_common *base) 1354 { 1355 struct sctp_endpoint *ep; 1356 1357 ep = container_of(base, struct sctp_endpoint, base); 1358 return ep; 1359 } 1360 1361 /* These are function signatures for manipulating endpoints. */ 1362 struct sctp_endpoint *sctp_endpoint_new(struct sock *, gfp_t); 1363 void sctp_endpoint_free(struct sctp_endpoint *); 1364 void sctp_endpoint_put(struct sctp_endpoint *); 1365 void sctp_endpoint_hold(struct sctp_endpoint *); 1366 void sctp_endpoint_add_asoc(struct sctp_endpoint *, struct sctp_association *); 1367 struct sctp_association *sctp_endpoint_lookup_assoc( 1368 const struct sctp_endpoint *ep, 1369 const union sctp_addr *paddr, 1370 struct sctp_transport **); 1371 bool sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep, 1372 const union sctp_addr *paddr); 1373 struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *, 1374 struct net *, const union sctp_addr *); 1375 bool sctp_has_association(struct net *net, const union sctp_addr *laddr, 1376 const union sctp_addr *paddr); 1377 1378 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep, 1379 const struct sctp_association *asoc, 1380 enum sctp_cid cid, struct sctp_init_chunk *peer_init, 1381 struct sctp_chunk *chunk, struct sctp_chunk **err_chunk); 1382 int sctp_process_init(struct sctp_association *, struct sctp_chunk *chunk, 1383 const union sctp_addr *peer, 1384 struct sctp_init_chunk *init, gfp_t gfp); 1385 __u32 sctp_generate_tag(const struct sctp_endpoint *); 1386 __u32 sctp_generate_tsn(const struct sctp_endpoint *); 1387 1388 struct sctp_inithdr_host { 1389 __u32 init_tag; 1390 __u32 a_rwnd; 1391 __u16 num_outbound_streams; 1392 __u16 num_inbound_streams; 1393 __u32 initial_tsn; 1394 }; 1395 1396 struct sctp_stream_priorities { 1397 /* List of priorities scheduled */ 1398 struct list_head prio_sched; 1399 /* List of streams scheduled */ 1400 struct list_head active; 1401 /* The next stream stream in line */ 1402 struct sctp_stream_out_ext *next; 1403 __u16 prio; 1404 }; 1405 1406 struct sctp_stream_out_ext { 1407 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 1408 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 1409 struct list_head outq; /* chunks enqueued by this stream */ 1410 union { 1411 struct { 1412 /* Scheduled streams list */ 1413 struct list_head prio_list; 1414 struct sctp_stream_priorities *prio_head; 1415 }; 1416 /* Fields used by RR scheduler */ 1417 struct { 1418 struct list_head rr_list; 1419 }; 1420 }; 1421 }; 1422 1423 struct sctp_stream_out { 1424 union { 1425 __u32 mid; 1426 __u16 ssn; 1427 }; 1428 __u32 mid_uo; 1429 struct sctp_stream_out_ext *ext; 1430 __u8 state; 1431 }; 1432 1433 struct sctp_stream_in { 1434 union { 1435 __u32 mid; 1436 __u16 ssn; 1437 }; 1438 __u32 mid_uo; 1439 __u32 fsn; 1440 __u32 fsn_uo; 1441 char pd_mode; 1442 char pd_mode_uo; 1443 }; 1444 1445 struct sctp_stream { 1446 GENRADIX(struct sctp_stream_out) out; 1447 GENRADIX(struct sctp_stream_in) in; 1448 1449 __u16 outcnt; 1450 __u16 incnt; 1451 /* Current stream being sent, if any */ 1452 struct sctp_stream_out *out_curr; 1453 union { 1454 /* Fields used by priority scheduler */ 1455 struct { 1456 /* List of priorities scheduled */ 1457 struct list_head prio_list; 1458 }; 1459 /* Fields used by RR scheduler */ 1460 struct { 1461 /* List of streams scheduled */ 1462 struct list_head rr_list; 1463 /* The next stream stream in line */ 1464 struct sctp_stream_out_ext *rr_next; 1465 }; 1466 }; 1467 struct sctp_stream_interleave *si; 1468 }; 1469 1470 static inline struct sctp_stream_out *sctp_stream_out( 1471 struct sctp_stream *stream, 1472 __u16 sid) 1473 { 1474 return genradix_ptr(&stream->out, sid); 1475 } 1476 1477 static inline struct sctp_stream_in *sctp_stream_in( 1478 struct sctp_stream *stream, 1479 __u16 sid) 1480 { 1481 return genradix_ptr(&stream->in, sid); 1482 } 1483 1484 #define SCTP_SO(s, i) sctp_stream_out((s), (i)) 1485 #define SCTP_SI(s, i) sctp_stream_in((s), (i)) 1486 1487 #define SCTP_STREAM_CLOSED 0x00 1488 #define SCTP_STREAM_OPEN 0x01 1489 1490 static inline __u16 sctp_datachk_len(const struct sctp_stream *stream) 1491 { 1492 return stream->si->data_chunk_len; 1493 } 1494 1495 static inline __u16 sctp_datahdr_len(const struct sctp_stream *stream) 1496 { 1497 return stream->si->data_chunk_len - sizeof(struct sctp_chunkhdr); 1498 } 1499 1500 static inline __u16 sctp_ftsnchk_len(const struct sctp_stream *stream) 1501 { 1502 return stream->si->ftsn_chunk_len; 1503 } 1504 1505 static inline __u16 sctp_ftsnhdr_len(const struct sctp_stream *stream) 1506 { 1507 return stream->si->ftsn_chunk_len - sizeof(struct sctp_chunkhdr); 1508 } 1509 1510 /* SCTP_GET_ASSOC_STATS counters */ 1511 struct sctp_priv_assoc_stats { 1512 /* Maximum observed rto in the association during subsequent 1513 * observations. Value is set to 0 if no RTO measurement took place 1514 * The transport where the max_rto was observed is returned in 1515 * obs_rto_ipaddr 1516 */ 1517 struct sockaddr_storage obs_rto_ipaddr; 1518 __u64 max_obs_rto; 1519 /* Total In and Out SACKs received and sent */ 1520 __u64 isacks; 1521 __u64 osacks; 1522 /* Total In and Out packets received and sent */ 1523 __u64 opackets; 1524 __u64 ipackets; 1525 /* Total retransmitted chunks */ 1526 __u64 rtxchunks; 1527 /* TSN received > next expected */ 1528 __u64 outofseqtsns; 1529 /* Duplicate Chunks received */ 1530 __u64 idupchunks; 1531 /* Gap Ack Blocks received */ 1532 __u64 gapcnt; 1533 /* Unordered data chunks sent and received */ 1534 __u64 ouodchunks; 1535 __u64 iuodchunks; 1536 /* Ordered data chunks sent and received */ 1537 __u64 oodchunks; 1538 __u64 iodchunks; 1539 /* Control chunks sent and received */ 1540 __u64 octrlchunks; 1541 __u64 ictrlchunks; 1542 }; 1543 1544 /* RFC2960 1545 * 1546 * 12. Recommended Transmission Control Block (TCB) Parameters 1547 * 1548 * This section details a recommended set of parameters that should 1549 * be contained within the TCB for an implementation. This section is 1550 * for illustrative purposes and should not be deemed as requirements 1551 * on an implementation or as an exhaustive list of all parameters 1552 * inside an SCTP TCB. Each implementation may need its own additional 1553 * parameters for optimization. 1554 */ 1555 1556 1557 /* Here we have information about each individual association. */ 1558 struct sctp_association { 1559 1560 /* A base structure common to endpoint and association. 1561 * In this context, it represents the associations's view 1562 * of the local endpoint of the association. 1563 */ 1564 struct sctp_ep_common base; 1565 1566 /* Associations on the same socket. */ 1567 struct list_head asocs; 1568 1569 /* association id. */ 1570 sctp_assoc_t assoc_id; 1571 1572 /* This is our parent endpoint. */ 1573 struct sctp_endpoint *ep; 1574 1575 /* These are those association elements needed in the cookie. */ 1576 struct sctp_cookie c; 1577 1578 /* This is all information about our peer. */ 1579 struct { 1580 /* transport_addr_list 1581 * 1582 * Peer : A list of SCTP transport addresses that the 1583 * Transport : peer is bound to. This information is derived 1584 * Address : from the INIT or INIT ACK and is used to 1585 * List : associate an inbound packet with a given 1586 * : association. Normally this information is 1587 * : hashed or keyed for quick lookup and access 1588 * : of the TCB. 1589 * : The list is also initialized with the list 1590 * : of addresses passed with the sctp_connectx() 1591 * : call. 1592 * 1593 * It is a list of SCTP_transport's. 1594 */ 1595 struct list_head transport_addr_list; 1596 1597 /* rwnd 1598 * 1599 * Peer Rwnd : Current calculated value of the peer's rwnd. 1600 */ 1601 __u32 rwnd; 1602 1603 /* transport_count 1604 * 1605 * Peer : A count of the number of peer addresses 1606 * Transport : in the Peer Transport Address List. 1607 * Address : 1608 * Count : 1609 */ 1610 __u16 transport_count; 1611 1612 /* port 1613 * The transport layer port number. 1614 */ 1615 __u16 port; 1616 1617 /* primary_path 1618 * 1619 * Primary : This is the current primary destination 1620 * Path : transport address of the peer endpoint. It 1621 * : may also specify a source transport address 1622 * : on this endpoint. 1623 * 1624 * All of these paths live on transport_addr_list. 1625 * 1626 * At the bakeoffs, we discovered that the intent of 1627 * primaryPath is that it only changes when the ULP 1628 * asks to have it changed. We add the activePath to 1629 * designate the connection we are currently using to 1630 * transmit new data and most control chunks. 1631 */ 1632 struct sctp_transport *primary_path; 1633 1634 /* Cache the primary path address here, when we 1635 * need a an address for msg_name. 1636 */ 1637 union sctp_addr primary_addr; 1638 1639 /* active_path 1640 * The path that we are currently using to 1641 * transmit new data and most control chunks. 1642 */ 1643 struct sctp_transport *active_path; 1644 1645 /* retran_path 1646 * 1647 * RFC2960 6.4 Multi-homed SCTP Endpoints 1648 * ... 1649 * Furthermore, when its peer is multi-homed, an 1650 * endpoint SHOULD try to retransmit a chunk to an 1651 * active destination transport address that is 1652 * different from the last destination address to 1653 * which the DATA chunk was sent. 1654 */ 1655 struct sctp_transport *retran_path; 1656 1657 /* Pointer to last transport I have sent on. */ 1658 struct sctp_transport *last_sent_to; 1659 1660 /* This is the last transport I have received DATA on. */ 1661 struct sctp_transport *last_data_from; 1662 1663 /* 1664 * Mapping An array of bits or bytes indicating which out of 1665 * Array order TSN's have been received (relative to the 1666 * Last Rcvd TSN). If no gaps exist, i.e. no out of 1667 * order packets have been received, this array 1668 * will be set to all zero. This structure may be 1669 * in the form of a circular buffer or bit array. 1670 * 1671 * Last Rcvd : This is the last TSN received in 1672 * TSN : sequence. This value is set initially by 1673 * : taking the peer's Initial TSN, received in 1674 * : the INIT or INIT ACK chunk, and subtracting 1675 * : one from it. 1676 * 1677 * Throughout most of the specification this is called the 1678 * "Cumulative TSN ACK Point". In this case, we 1679 * ignore the advice in 12.2 in favour of the term 1680 * used in the bulk of the text. This value is hidden 1681 * in tsn_map--we get it by calling sctp_tsnmap_get_ctsn(). 1682 */ 1683 struct sctp_tsnmap tsn_map; 1684 1685 /* This mask is used to disable sending the ASCONF chunk 1686 * with specified parameter to peer. 1687 */ 1688 __be16 addip_disabled_mask; 1689 1690 /* These are capabilities which our peer advertised. */ 1691 __u16 ecn_capable:1, /* Can peer do ECN? */ 1692 ipv4_address:1, /* Peer understands IPv4 addresses? */ 1693 ipv6_address:1, /* Peer understands IPv6 addresses? */ 1694 hostname_address:1, /* Peer understands DNS addresses? */ 1695 asconf_capable:1, /* Does peer support ADDIP? */ 1696 prsctp_capable:1, /* Can peer do PR-SCTP? */ 1697 reconf_capable:1, /* Can peer do RE-CONFIG? */ 1698 intl_capable:1, /* Can peer do INTERLEAVE */ 1699 auth_capable:1, /* Is peer doing SCTP-AUTH? */ 1700 /* sack_needed: 1701 * This flag indicates if the next received 1702 * packet is to be responded to with a 1703 * SACK. This is initialized to 0. When a packet 1704 * is received sack_cnt is incremented. If this value 1705 * reaches 2 or more, a SACK is sent and the 1706 * value is reset to 0. Note: This is used only 1707 * when no DATA chunks are received out of 1708 * order. When DATA chunks are out of order, 1709 * SACK's are not delayed (see Section 6). 1710 */ 1711 sack_needed:1, /* Do we need to sack the peer? */ 1712 sack_generation:1, 1713 zero_window_announced:1; 1714 1715 __u32 sack_cnt; 1716 1717 __u32 adaptation_ind; /* Adaptation Code point. */ 1718 1719 struct sctp_inithdr_host i; 1720 void *cookie; 1721 int cookie_len; 1722 1723 /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. 1724 * C1) ... "Peer-Serial-Number'. This value MUST be initialized to the 1725 * Initial TSN Value minus 1 1726 */ 1727 __u32 addip_serial; 1728 1729 /* SCTP-AUTH: We need to know pears random number, hmac list 1730 * and authenticated chunk list. All that is part of the 1731 * cookie and these are just pointers to those locations 1732 */ 1733 struct sctp_random_param *peer_random; 1734 struct sctp_chunks_param *peer_chunks; 1735 struct sctp_hmac_algo_param *peer_hmacs; 1736 } peer; 1737 1738 /* State : A state variable indicating what state the 1739 * : association is in, i.e. COOKIE-WAIT, 1740 * : COOKIE-ECHOED, ESTABLISHED, SHUTDOWN-PENDING, 1741 * : SHUTDOWN-SENT, SHUTDOWN-RECEIVED, SHUTDOWN-ACK-SENT. 1742 * 1743 * Note: No "CLOSED" state is illustrated since if a 1744 * association is "CLOSED" its TCB SHOULD be removed. 1745 * 1746 * In this implementation we DO have a CLOSED 1747 * state which is used during initiation and shutdown. 1748 * 1749 * State takes values from SCTP_STATE_*. 1750 */ 1751 enum sctp_state state; 1752 1753 /* Overall : The overall association error count. 1754 * Error Count : [Clear this any time I get something.] 1755 */ 1756 int overall_error_count; 1757 1758 /* The cookie life I award for any cookie. */ 1759 ktime_t cookie_life; 1760 1761 /* These are the association's initial, max, and min RTO values. 1762 * These values will be initialized by system defaults, but can 1763 * be modified via the SCTP_RTOINFO socket option. 1764 */ 1765 unsigned long rto_initial; 1766 unsigned long rto_max; 1767 unsigned long rto_min; 1768 1769 /* Maximum number of new data packets that can be sent in a burst. */ 1770 int max_burst; 1771 1772 /* This is the max_retrans value for the association. This value will 1773 * be initialized initialized from system defaults, but can be 1774 * modified by the SCTP_ASSOCINFO socket option. 1775 */ 1776 int max_retrans; 1777 1778 /* This is the partially failed retrans value for the transport 1779 * and will be initialized from the assocs value. This can be 1780 * changed using the SCTP_PEER_ADDR_THLDS socket option 1781 */ 1782 __u16 pf_retrans; 1783 /* Used for primary path switchover. */ 1784 __u16 ps_retrans; 1785 1786 /* Maximum number of times the endpoint will retransmit INIT */ 1787 __u16 max_init_attempts; 1788 1789 /* How many times have we resent an INIT? */ 1790 __u16 init_retries; 1791 1792 /* The largest timeout or RTO value to use in attempting an INIT */ 1793 unsigned long max_init_timeo; 1794 1795 /* Heartbeat interval: The endpoint sends out a Heartbeat chunk to 1796 * the destination address every heartbeat interval. This value 1797 * will be inherited by all new transports. 1798 */ 1799 unsigned long hbinterval; 1800 1801 /* This is the max_retrans value for new transports in the 1802 * association. 1803 */ 1804 __u16 pathmaxrxt; 1805 1806 __u32 flowlabel; 1807 __u8 dscp; 1808 1809 /* Flag that path mtu update is pending */ 1810 __u8 pmtu_pending; 1811 1812 /* Association : The smallest PMTU discovered for all of the 1813 * PMTU : peer's transport addresses. 1814 */ 1815 __u32 pathmtu; 1816 1817 /* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */ 1818 __u32 param_flags; 1819 1820 __u32 sackfreq; 1821 /* SACK delay timeout */ 1822 unsigned long sackdelay; 1823 1824 unsigned long timeouts[SCTP_NUM_TIMEOUT_TYPES]; 1825 struct timer_list timers[SCTP_NUM_TIMEOUT_TYPES]; 1826 1827 /* Transport to which SHUTDOWN chunk was last sent. */ 1828 struct sctp_transport *shutdown_last_sent_to; 1829 1830 /* Transport to which INIT chunk was last sent. */ 1831 struct sctp_transport *init_last_sent_to; 1832 1833 /* How many times have we resent a SHUTDOWN */ 1834 int shutdown_retries; 1835 1836 /* Next TSN : The next TSN number to be assigned to a new 1837 * : DATA chunk. This is sent in the INIT or INIT 1838 * : ACK chunk to the peer and incremented each 1839 * : time a DATA chunk is assigned a TSN 1840 * : (normally just prior to transmit or during 1841 * : fragmentation). 1842 */ 1843 __u32 next_tsn; 1844 1845 /* 1846 * Last Rcvd : This is the last TSN received in sequence. This value 1847 * TSN : is set initially by taking the peer's Initial TSN, 1848 * : received in the INIT or INIT ACK chunk, and 1849 * : subtracting one from it. 1850 * 1851 * Most of RFC 2960 refers to this as the Cumulative TSN Ack Point. 1852 */ 1853 1854 __u32 ctsn_ack_point; 1855 1856 /* PR-SCTP Advanced.Peer.Ack.Point */ 1857 __u32 adv_peer_ack_point; 1858 1859 /* Highest TSN that is acknowledged by incoming SACKs. */ 1860 __u32 highest_sacked; 1861 1862 /* TSN marking the fast recovery exit point */ 1863 __u32 fast_recovery_exit; 1864 1865 /* Flag to track the current fast recovery state */ 1866 __u8 fast_recovery; 1867 1868 /* The number of unacknowledged data chunks. Reported through 1869 * the SCTP_STATUS sockopt. 1870 */ 1871 __u16 unack_data; 1872 1873 /* The total number of data chunks that we've had to retransmit 1874 * as the result of a T3 timer expiration 1875 */ 1876 __u32 rtx_data_chunks; 1877 1878 /* This is the association's receive buffer space. This value is used 1879 * to set a_rwnd field in an INIT or a SACK chunk. 1880 */ 1881 __u32 rwnd; 1882 1883 /* This is the last advertised value of rwnd over a SACK chunk. */ 1884 __u32 a_rwnd; 1885 1886 /* Number of bytes by which the rwnd has slopped. The rwnd is allowed 1887 * to slop over a maximum of the association's frag_point. 1888 */ 1889 __u32 rwnd_over; 1890 1891 /* Keeps treack of rwnd pressure. This happens when we have 1892 * a window, but not recevie buffer (i.e small packets). This one 1893 * is releases slowly (1 PMTU at a time ). 1894 */ 1895 __u32 rwnd_press; 1896 1897 /* This is the sndbuf size in use for the association. 1898 * This corresponds to the sndbuf size for the association, 1899 * as specified in the sk->sndbuf. 1900 */ 1901 int sndbuf_used; 1902 1903 /* This is the amount of memory that this association has allocated 1904 * in the receive path at any given time. 1905 */ 1906 atomic_t rmem_alloc; 1907 1908 /* This is the wait queue head for send requests waiting on 1909 * the association sndbuf space. 1910 */ 1911 wait_queue_head_t wait; 1912 1913 /* The message size at which SCTP fragmentation will occur. */ 1914 __u32 frag_point; 1915 __u32 user_frag; 1916 1917 /* Counter used to count INIT errors. */ 1918 int init_err_counter; 1919 1920 /* Count the number of INIT cycles (for doubling timeout). */ 1921 int init_cycle; 1922 1923 /* Default send parameters. */ 1924 __u16 default_stream; 1925 __u16 default_flags; 1926 __u32 default_ppid; 1927 __u32 default_context; 1928 __u32 default_timetolive; 1929 1930 /* Default receive parameters */ 1931 __u32 default_rcv_context; 1932 1933 /* Stream arrays */ 1934 struct sctp_stream stream; 1935 1936 /* All outbound chunks go through this structure. */ 1937 struct sctp_outq outqueue; 1938 1939 /* A smart pipe that will handle reordering and fragmentation, 1940 * as well as handle passing events up to the ULP. 1941 */ 1942 struct sctp_ulpq ulpq; 1943 1944 /* Last TSN that caused an ECNE Chunk to be sent. */ 1945 __u32 last_ecne_tsn; 1946 1947 /* Last TSN that caused a CWR Chunk to be sent. */ 1948 __u32 last_cwr_tsn; 1949 1950 /* How many duplicated TSNs have we seen? */ 1951 int numduptsns; 1952 1953 /* These are to support 1954 * "SCTP Extensions for Dynamic Reconfiguration of IP Addresses 1955 * and Enforcement of Flow and Message Limits" 1956 * <draft-ietf-tsvwg-addip-sctp-02.txt> 1957 * or "ADDIP" for short. 1958 */ 1959 1960 1961 1962 /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1963 * 1964 * R1) One and only one ASCONF Chunk MAY be in transit and 1965 * unacknowledged at any one time. If a sender, after sending 1966 * an ASCONF chunk, decides it needs to transfer another 1967 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 1968 * returns from the previous ASCONF Chunk before sending a 1969 * subsequent ASCONF. Note this restriction binds each side, 1970 * so at any time two ASCONF may be in-transit on any given 1971 * association (one sent from each endpoint). 1972 * 1973 * [This is our one-and-only-one ASCONF in flight. If we do 1974 * not have an ASCONF in flight, this is NULL.] 1975 */ 1976 struct sctp_chunk *addip_last_asconf; 1977 1978 /* ADDIP Section 5.2 Upon reception of an ASCONF Chunk. 1979 * 1980 * This is needed to implement itmes E1 - E4 of the updated 1981 * spec. Here is the justification: 1982 * 1983 * Since the peer may bundle multiple ASCONF chunks toward us, 1984 * we now need the ability to cache multiple ACKs. The section 1985 * describes in detail how they are cached and cleaned up. 1986 */ 1987 struct list_head asconf_ack_list; 1988 1989 /* These ASCONF chunks are waiting to be sent. 1990 * 1991 * These chunaks can't be pushed to outqueue until receiving 1992 * ASCONF_ACK for the previous ASCONF indicated by 1993 * addip_last_asconf, so as to guarantee that only one ASCONF 1994 * is in flight at any time. 1995 * 1996 * ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks 1997 * 1998 * In defining the ASCONF Chunk transfer procedures, it is 1999 * essential that these transfers MUST NOT cause congestion 2000 * within the network. To achieve this, we place these 2001 * restrictions on the transfer of ASCONF Chunks: 2002 * 2003 * R1) One and only one ASCONF Chunk MAY be in transit and 2004 * unacknowledged at any one time. If a sender, after sending 2005 * an ASCONF chunk, decides it needs to transfer another 2006 * ASCONF Chunk, it MUST wait until the ASCONF-ACK Chunk 2007 * returns from the previous ASCONF Chunk before sending a 2008 * subsequent ASCONF. Note this restriction binds each side, 2009 * so at any time two ASCONF may be in-transit on any given 2010 * association (one sent from each endpoint). 2011 * 2012 * 2013 * [I really think this is EXACTLY the sort of intelligence 2014 * which already resides in sctp_outq. Please move this 2015 * queue and its supporting logic down there. --piggy] 2016 */ 2017 struct list_head addip_chunk_list; 2018 2019 /* ADDIP Section 4.1 ASCONF Chunk Procedures 2020 * 2021 * A2) A serial number should be assigned to the Chunk. The 2022 * serial number SHOULD be a monotonically increasing 2023 * number. The serial number SHOULD be initialized at 2024 * the start of the association to the same value as the 2025 * Initial TSN and every time a new ASCONF chunk is created 2026 * it is incremented by one after assigning the serial number 2027 * to the newly created chunk. 2028 * 2029 * ADDIP 2030 * 3.1.1 Address/Stream Configuration Change Chunk (ASCONF) 2031 * 2032 * Serial Number : 32 bits (unsigned integer) 2033 * 2034 * This value represents a Serial Number for the ASCONF 2035 * Chunk. The valid range of Serial Number is from 0 to 2036 * 4294967295 (2^32 - 1). Serial Numbers wrap back to 0 2037 * after reaching 4294967295. 2038 */ 2039 __u32 addip_serial; 2040 int src_out_of_asoc_ok; 2041 union sctp_addr *asconf_addr_del_pending; 2042 struct sctp_transport *new_transport; 2043 2044 /* SCTP AUTH: list of the endpoint shared keys. These 2045 * keys are provided out of band by the user applicaton 2046 * and can't change during the lifetime of the association 2047 */ 2048 struct list_head endpoint_shared_keys; 2049 2050 /* SCTP AUTH: 2051 * The current generated assocaition shared key (secret) 2052 */ 2053 struct sctp_auth_bytes *asoc_shared_key; 2054 struct sctp_shared_key *shkey; 2055 2056 /* SCTP AUTH: hmac id of the first peer requested algorithm 2057 * that we support. 2058 */ 2059 __u16 default_hmac_id; 2060 2061 __u16 active_key_id; 2062 2063 __u8 need_ecne:1, /* Need to send an ECNE Chunk? */ 2064 temp:1, /* Is it a temporary association? */ 2065 pf_expose:2, /* Expose pf state? */ 2066 force_delay:1; 2067 2068 __u8 strreset_enable; 2069 __u8 strreset_outstanding; /* request param count on the fly */ 2070 2071 __u32 strreset_outseq; /* Update after receiving response */ 2072 __u32 strreset_inseq; /* Update after receiving request */ 2073 __u32 strreset_result[2]; /* save the results of last 2 responses */ 2074 2075 struct sctp_chunk *strreset_chunk; /* save request chunk */ 2076 2077 struct sctp_priv_assoc_stats stats; 2078 2079 int sent_cnt_removable; 2080 2081 __u16 subscribe; 2082 2083 __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; 2084 __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; 2085 2086 struct rcu_head rcu; 2087 }; 2088 2089 2090 /* An eyecatcher for determining if we are really looking at an 2091 * association data structure. 2092 */ 2093 enum { 2094 SCTP_ASSOC_EYECATCHER = 0xa550c123, 2095 }; 2096 2097 /* Recover the outter association structure. */ 2098 static inline struct sctp_association *sctp_assoc(struct sctp_ep_common *base) 2099 { 2100 struct sctp_association *asoc; 2101 2102 asoc = container_of(base, struct sctp_association, base); 2103 return asoc; 2104 } 2105 2106 /* These are function signatures for manipulating associations. */ 2107 2108 2109 struct sctp_association * 2110 sctp_association_new(const struct sctp_endpoint *ep, const struct sock *sk, 2111 enum sctp_scope scope, gfp_t gfp); 2112 void sctp_association_free(struct sctp_association *); 2113 void sctp_association_put(struct sctp_association *); 2114 void sctp_association_hold(struct sctp_association *); 2115 2116 struct sctp_transport *sctp_assoc_choose_alter_transport( 2117 struct sctp_association *, struct sctp_transport *); 2118 void sctp_assoc_update_retran_path(struct sctp_association *); 2119 struct sctp_transport *sctp_assoc_lookup_paddr(const struct sctp_association *, 2120 const union sctp_addr *); 2121 int sctp_assoc_lookup_laddr(struct sctp_association *asoc, 2122 const union sctp_addr *laddr); 2123 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *, 2124 const union sctp_addr *address, 2125 const gfp_t gfp, 2126 const int peer_state); 2127 void sctp_assoc_del_peer(struct sctp_association *asoc, 2128 const union sctp_addr *addr); 2129 void sctp_assoc_rm_peer(struct sctp_association *asoc, 2130 struct sctp_transport *peer); 2131 void sctp_assoc_control_transport(struct sctp_association *asoc, 2132 struct sctp_transport *transport, 2133 enum sctp_transport_cmd command, 2134 sctp_sn_error_t error); 2135 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *, __u32); 2136 void sctp_assoc_migrate(struct sctp_association *, struct sock *); 2137 int sctp_assoc_update(struct sctp_association *old, 2138 struct sctp_association *new); 2139 2140 __u32 sctp_association_get_next_tsn(struct sctp_association *); 2141 2142 void sctp_assoc_update_frag_point(struct sctp_association *asoc); 2143 void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu); 2144 void sctp_assoc_sync_pmtu(struct sctp_association *asoc); 2145 void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int); 2146 void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int); 2147 void sctp_assoc_set_primary(struct sctp_association *, 2148 struct sctp_transport *); 2149 void sctp_assoc_del_nonprimary_peers(struct sctp_association *, 2150 struct sctp_transport *); 2151 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, 2152 enum sctp_scope scope, gfp_t gfp); 2153 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *, 2154 struct sctp_cookie*, 2155 gfp_t gfp); 2156 int sctp_assoc_set_id(struct sctp_association *, gfp_t); 2157 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc); 2158 struct sctp_chunk *sctp_assoc_lookup_asconf_ack( 2159 const struct sctp_association *asoc, 2160 __be32 serial); 2161 void sctp_asconf_queue_teardown(struct sctp_association *asoc); 2162 2163 int sctp_cmp_addr_exact(const union sctp_addr *ss1, 2164 const union sctp_addr *ss2); 2165 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc); 2166 2167 /* A convenience structure to parse out SCTP specific CMSGs. */ 2168 struct sctp_cmsgs { 2169 struct sctp_initmsg *init; 2170 struct sctp_sndrcvinfo *srinfo; 2171 struct sctp_sndinfo *sinfo; 2172 struct sctp_prinfo *prinfo; 2173 struct sctp_authinfo *authinfo; 2174 struct msghdr *addrs_msg; 2175 }; 2176 2177 /* Structure for tracking memory objects */ 2178 struct sctp_dbg_objcnt_entry { 2179 char *label; 2180 atomic_t *counter; 2181 }; 2182 2183 #endif /* __sctp_structs_h__ */ 2184